doc: improve NEWS

Add a notable enhancement from 4.0-pre1 and make the description of
another enhancement less ambiguous.

.gitignore

@@ -1,24 +1,28 @@
 .deps
 .vimrc
+*.gcda
+*.gcno
 *.o
 *.swp
 *.dSYM
 *.DS_Store
+core.*
 tags
 /RELEASES
 /Makefile
-/chrony.conf.5
-/chrony.info
-/chrony.html
-/chrony.texi
-/chrony.txt
 /chronyc
-/chronyc.1
 /chronyd
-/chronyd.8
 /config.h
 /config.log
+/doc/Makefile
+/doc/*.html
+/doc/*.man
+/doc/*.man.in
+/doc/*.txt
 /getdate.c
 /version.h
 /test/simulation/clknetsim
 /test/simulation/tmp
+/test/unit/Makefile
+/test/unit/*.test
+/test/unit/*.o

Makefile.in

@@ -21,64 +21,56 @@
 #
 # Makefile template
 
-SYSCONFDIR=@SYSCONFDIR@
-BINDIR=@BINDIR@
-SBINDIR=@SBINDIR@
-MANDIR=@MANDIR@
-INFODIR=@INFODIR@
-DOCDIR=@DOCDIR@
-LOCALSTATEDIR=@LOCALSTATEDIR@
-CHRONYVARDIR=@CHRONYVARDIR@
+SYSCONFDIR = @SYSCONFDIR@
+BINDIR = @BINDIR@
+SBINDIR = @SBINDIR@
+LOCALSTATEDIR = @LOCALSTATEDIR@
+CHRONYVARDIR = @CHRONYVARDIR@
+DESTDIR =
 
 CC = @CC@
 CFLAGS = @CFLAGS@
 CPPFLAGS = @CPPFLAGS@
+LDFLAGS = @LDFLAGS@
 
-DESTDIR=
-
-HASH_OBJ = @HASH_OBJ@
+EXTRA_OBJS = @EXTRA_OBJS@
 
 OBJS = array.o cmdparse.o conf.o local.o logging.o main.o memory.o \
-       reference.o regress.o rtc.o sched.o sources.o sourcestats.o stubs.o \
-       sys.o smooth.o tempcomp.o util.o $(HASH_OBJ)
+       reference.o regress.o rtc.o samplefilt.o sched.o socket.o sources.o sourcestats.o \
+       stubs.o smooth.o sys.o sys_null.o tempcomp.o util.o $(EXTRA_OBJS)
 
-EXTRA_OBJS=@EXTRA_OBJECTS@
+EXTRA_CLI_OBJS = @EXTRA_CLI_OBJS@
 
 CLI_OBJS = array.o client.o cmdparse.o getdate.o memory.o nameserv.o \
-           pktlength.o util.o $(HASH_OBJ)
+           pktlength.o socket.o util.o $(EXTRA_CLI_OBJS)
 
-ALL_OBJS = $(OBJS) $(EXTRA_OBJS) $(CLI_OBJS)
+ALL_OBJS = $(OBJS) $(CLI_OBJS)
 
-LDFLAGS = @LDFLAGS@
 LIBS = @LIBS@
-
-EXTRA_LIBS=@EXTRA_LIBS@
-EXTRA_CLI_LIBS=@EXTRA_CLI_LIBS@
+EXTRA_LIBS = @EXTRA_LIBS@
+EXTRA_CLI_LIBS = @EXTRA_CLI_LIBS@
 
 # Until we have a main procedure we can link, just build object files
 # to test compilation
 
 all : chronyd chronyc
 
-chronyd : $(OBJS) $(EXTRA_OBJS)
-	$(CC) $(CFLAGS) -o chronyd $(OBJS) $(EXTRA_OBJS) $(LDFLAGS) $(LIBS) $(EXTRA_LIBS)
+chronyd : $(OBJS)
+	$(CC) $(CFLAGS) -o chronyd $(OBJS) $(LDFLAGS) $(LIBS) $(EXTRA_LIBS)
 
 chronyc : $(CLI_OBJS)
 	$(CC) $(CFLAGS) -o chronyc $(CLI_OBJS) $(LDFLAGS) $(LIBS) $(EXTRA_CLI_LIBS)
 
-client.o : client.c
-	$(CC) $(CFLAGS) $(CPPFLAGS) @READLINE_COMPILE@ -c $<
-
-$(HASH_OBJ) : $(patsubst %.o,%.c,$(HASH_OBJ))
-	$(CC) $(CFLAGS) $(CPPFLAGS) @HASH_COMPILE@ -c $<
-
 distclean : clean
+	$(MAKE) -C doc distclean
+	$(MAKE) -C test/unit distclean
 	-rm -f .DS_Store
-	-rm -f Makefile
-	-rm -f chrony.conf.5 chrony.texi chronyc.1 chronyd.8
+	-rm -f Makefile config.h config.log
 
 clean :
-	-rm -f *.o *.s chronyc chronyd core *~ chrony.info chrony.html chrony.txt
+	$(MAKE) -C test/unit clean
+	-rm -f *.o *.s chronyc chronyd core.* *~
+	-rm -f *.gcda *.gcno
 	-rm -rf .deps
 	-rm -rf *.dSYM
 
@@ -96,9 +88,6 @@ install: chronyd chronyc
 	[ -d $(DESTDIR)$(SYSCONFDIR) ] || mkdir -p $(DESTDIR)$(SYSCONFDIR)
 	[ -d $(DESTDIR)$(SBINDIR) ] || mkdir -p $(DESTDIR)$(SBINDIR)
 	[ -d $(DESTDIR)$(BINDIR) ] || mkdir -p $(DESTDIR)$(BINDIR)
-	[ -d $(DESTDIR)$(MANDIR)/man1 ] || mkdir -p $(DESTDIR)$(MANDIR)/man1
-	[ -d $(DESTDIR)$(MANDIR)/man5 ] || mkdir -p $(DESTDIR)$(MANDIR)/man5
-	[ -d $(DESTDIR)$(MANDIR)/man8 ] || mkdir -p $(DESTDIR)$(MANDIR)/man8
 	[ -d $(DESTDIR)$(CHRONYVARDIR) ] || mkdir -p $(DESTDIR)$(CHRONYVARDIR)
 	if [ -f $(DESTDIR)$(SBINDIR)/chronyd ]; then rm -f $(DESTDIR)$(SBINDIR)/chronyd ; fi
 	if [ -f $(DESTDIR)$(BINDIR)/chronyc ]; then rm -f $(DESTDIR)$(BINDIR)/chronyc ; fi
@@ -106,12 +95,13 @@ install: chronyd chronyc
 	chmod 755 $(DESTDIR)$(SBINDIR)/chronyd
 	cp chronyc $(DESTDIR)$(BINDIR)/chronyc
 	chmod 755 $(DESTDIR)$(BINDIR)/chronyc
-	cp chronyc.1 $(DESTDIR)$(MANDIR)/man1
-	chmod 644 $(DESTDIR)$(MANDIR)/man1/chronyc.1
-	cp chronyd.8 $(DESTDIR)$(MANDIR)/man8
-	chmod 644 $(DESTDIR)$(MANDIR)/man8/chronyd.8
-	cp chrony.conf.5 $(DESTDIR)$(MANDIR)/man5
-	chmod 644 $(DESTDIR)$(MANDIR)/man5/chrony.conf.5
+	$(MAKE) -C doc install
+
+docs :
+	$(MAKE) -C doc docs
+
+install-docs :
+	$(MAKE) -C doc install-docs
 
 %.o : %.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) -c $<
@@ -119,30 +109,18 @@ install: chronyd chronyc
 %.s : %.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) -S $<
 
-check : chronyd chronyc
+quickcheck : chronyd chronyc
+	$(MAKE) -C test/unit check
 	cd test/simulation && ./run
+	cd test/system && ./run
 
-install-docs : docs
-	[ -d $(DESTDIR)$(DOCDIR) ] || mkdir -p $(DESTDIR)$(DOCDIR)
-	cp chrony.txt $(DESTDIR)$(DOCDIR)/chrony.txt
-	chmod 644 $(DESTDIR)$(DOCDIR)/chrony.txt
-	cp chrony.html $(DESTDIR)$(DOCDIR)/chrony.html
-	chmod 644 $(DESTDIR)$(DOCDIR)/chrony.html
-	[ -d $(DESTDIR)$(INFODIR) ] || mkdir -p $(DESTDIR)$(INFODIR)
-	cp chrony.info* $(DESTDIR)$(INFODIR)
-	chmod 644 $(DESTDIR)$(INFODIR)/chrony.info*
+check : chronyd chronyc
+	$(MAKE) -C test/unit check
+	cd test/simulation && ./run -i 20 -m 2
+	cd test/system && ./run
 
-docs : chrony.txt chrony.html chrony.info
-
-chrony.txt : chrony.texi
-	makeinfo --no-headers --number-sections -o chrony.txt chrony.texi
-
-chrony.html : chrony.texi
-	command -v texi2html > /dev/null 2>&1 && texi2html chrony.texi || \
-	  makeinfo --no-split --html --number-sections -o chrony.html chrony.texi
-
-chrony.info : chrony.texi
-	makeinfo chrony.texi
+print-chronyd-objects :
+	@echo $(OBJS)
 
 Makefile : Makefile.in configure
 	@echo

NEWS

@@ -1,3 +1,255 @@
+New in version 4.0
+==================
+
+Enhancements
+------------
+* Add support for Network Time Security (NTS) authentication
+* Add support for AES-CMAC keys (AES128, AES256) with Nettle
+* Add support for maxsamples of 1 for faster update with -q/-Q option
+* Add -L option to limit log messages by severity
+* Avoid replacing NTP sources with sources that have unreachable address
+* Improve pools to repeat name resolution to get "maxsources" sources
+* Improve NTP loop test to prevent synchronisation to itself
+* Update clock synchronisation status and leap status more frequently
+* Update seccomp filter
+* Add "add pool" command
+* Add -N option and sourcename command to print original names of sources
+* Add -a option to sources/sourcestats command to print unresolved sources
+* Add reset command to drop all measurements
+
+Bug fixes
+---------
+* Handle RTCs that don't support interrupts
+* Respond to command requests with correct address on multihomed hosts
+
+Removed features
+----------------
+* Drop support for RIPEMD keys (RMD128, RMD160, RMD256, RMD320)
+
+New in version 3.5
+==================
+
+Enhancements
+------------
+* Add support for more accurate reading of PHC on Linux 5.0
+* Add support for hardware timestamping on interfaces with read-only
+  timestamping configuration
+* Add support for memory locking and real-time priority on FreeBSD,
+  NetBSD, Solaris
+* Update seccomp filter to work on more architectures
+* Validate refclock driver options
+
+Bug fixes
+---------
+* Fix bindaddress directive on FreeBSD
+* Fix transposition of hardware RX timestamp on Linux 4.13 and later
+* Fix building on non-glibc systems
+
+New in version 3.4
+==================
+
+Enhancements
+------------
+* Add filter option to server/pool/peer directive
+* Add minsamples and maxsamples options to hwtimestamp directive
+* Add support for faster frequency adjustments in Linux 4.19
+* Change default pidfile to /var/run/chrony/chronyd.pid to allow
+  chronyd without root privileges to remove it on exit
+* Disable sub-second polling intervals for distant NTP sources
+* Extend range of supported sub-second polling intervals
+* Get/set IPv4 destination/source address of NTP packets on FreeBSD
+* Make burst options and command useful with short polling intervals
+* Modify auto_offline option to activate when sending request failed
+* Respond from interface that received NTP request if possible
+* Add onoffline command to switch between online and offline state
+  according to current system network configuration
+* Improve example NetworkManager dispatcher script
+
+Bug fixes
+---------
+* Avoid waiting in Linux getrandom system call
+* Fix PPS support on FreeBSD and NetBSD
+
+New in version 3.3
+==================
+
+Enhancements
+------------
+* Add burst option to server/pool directive
+* Add stratum and tai options to refclock directive
+* Add support for Nettle crypto library
+* Add workaround for missing kernel receive timestamps on Linux
+* Wait for late hardware transmit timestamps
+* Improve source selection with unreachable sources
+* Improve protection against replay attacks on symmetric mode
+* Allow PHC refclock to use socket in /var/run/chrony
+* Add shutdown command to stop chronyd
+* Simplify format of response to manual list command
+* Improve handling of unknown responses in chronyc
+
+Bug fixes
+---------
+* Respond to NTPv1 client requests with zero mode
+* Fix -x option to not require CAP_SYS_TIME under non-root user
+* Fix acquisitionport directive to work with privilege separation
+* Fix handling of socket errors on Linux to avoid high CPU usage
+* Fix chronyc to not get stuck in infinite loop after clock step
+
+New in version 3.2
+==================
+
+Enhancements
+------------
+* Improve stability with NTP sources and reference clocks
+* Improve stability with hardware timestamping
+* Improve support for NTP interleaved modes
+* Control frequency of system clock on macOS 10.13 and later
+* Set TAI-UTC offset of system clock with leapsectz directive
+* Minimise data in client requests to improve privacy
+* Allow transmit-only hardware timestamping
+* Add support for new timestamping options introduced in Linux 4.13
+* Add root delay, root dispersion and maximum error to tracking log
+* Add mindelay and asymmetry options to server/peer/pool directive
+* Add extpps option to PHC refclock to timestamp external PPS signal
+* Add pps option to refclock directive to treat any refclock as PPS
+* Add width option to refclock directive to filter wrong pulse edges
+* Add rxfilter option to hwtimestamp directive
+* Add -x option to disable control of system clock
+* Add -l option to log to specified file instead of syslog
+* Allow multiple command-line options to be specified together
+* Allow starting without root privileges with -Q option
+* Update seccomp filter for new glibc versions
+* Dump history on exit by default with dumpdir directive
+* Use hardening compiler options by default
+
+Bug fixes
+---------
+* Don't drop PHC samples with low-resolution system clock
+* Ignore outliers in PHC tracking, RTC tracking, manual input
+* Increase polling interval when peer is not responding
+* Exit with error message when include directive fails
+* Don't allow slash after hostname in allow/deny directive/command
+* Try to connect to all addresses in chronyc before giving up
+
+New in version 3.1
+==================
+
+Enhancements
+------------
+* Add support for precise cross timestamping of PHC on Linux
+* Add minpoll, precision, nocrossts options to hwtimestamp directive
+* Add rawmeasurements option to log directive and modify measurements
+  option to log only valid measurements from synchronised sources
+* Allow sub-second polling interval with NTP sources
+
+Bug fixes
+---------
+* Fix time smoothing in interleaved mode
+
+New in version 3.0
+==================
+
+Enhancements
+------------
+* Add support for software and hardware timestamping on Linux
+* Add support for client/server and symmetric interleaved modes
+* Add support for MS-SNTP authentication in Samba
+* Add support for truncated MACs in NTPv4 packets
+* Estimate and correct for asymmetric network jitter
+* Increase default minsamples and polltarget to improve stability
+  with very low jitter
+* Add maxjitter directive to limit source selection by jitter
+* Add offset option to server/pool/peer directive
+* Add maxlockage option to refclock directive
+* Add -t option to chronyd to exit after specified time
+* Add partial protection against replay attacks on symmetric mode
+* Don't reset polling interval when switching sources to online state
+* Allow rate limiting with very short intervals
+* Improve maximum server throughput on Linux and NetBSD
+* Remove dump files after start
+* Add tab-completion to chronyc with libedit/readline
+* Add ntpdata command to print details about NTP measurements
+* Allow all source options to be set in add server/peer command
+* Indicate truncated addresses/hostnames in chronyc output
+* Print reference IDs as hexadecimal numbers to avoid confusion with
+  IPv4 addresses
+
+Bug fixes
+---------
+* Fix crash with disabled asynchronous name resolving
+
+New in version 2.4.1
+====================
+
+Bug fixes
+---------
+* Fix processing of kernel timestamps on non-Linux systems
+* Fix crash with smoothtime directive
+* Fix validation of refclock sample times
+* Fix parsing of refclock directive
+
+New in version 2.4
+==================
+
+Enhancements
+------------
+* Add orphan option to local directive for orphan mode compatible with ntpd
+* Add distance option to local directive to set activation threshold
+  (1 second by default)
+* Add maxdrift directive to set maximum allowed drift of system clock
+* Try to replace NTP sources exceeding maximum distance
+* Randomise source replacement to avoid getting stuck with bad sources
+* Randomise selection of sources from pools on start
+* Ignore reference timestamp as ntpd doesn't always set it correctly
+* Modify tracking report to use same values as seen by NTP clients
+* Add -c option to chronyc to write reports in CSV format
+* Provide detailed manual pages
+
+Bug fixes
+---------
+* Fix SOCK refclock to work correctly when not specified as last refclock
+* Fix initstepslew and -q/-Q options to accept time from own NTP clients
+* Fix authentication with keys using 512-bit hash functions
+* Fix crash on exit when multiple signals are received
+* Fix conversion of very small floating-point numbers in command packets
+
+Removed features
+----------------
+* Drop documentation in Texinfo format
+
+New in version 2.3
+==================
+
+Enhancements
+------------
+* Add support for NTP and command response rate limiting
+* Add support for dropping root privileges on Mac OS X, FreeBSD, Solaris
+* Add require and trust options for source selection
+* Enable logchange by default (1 second threshold)
+* Set RTC on Mac OS X with rtcsync directive
+* Allow binding to NTP port after dropping root privileges on NetBSD
+* Drop CAP_NET_BIND_SERVICE capability on Linux when NTP port is disabled
+* Resolve names in separate process when seccomp filter is enabled
+* Replace old records in client log when memory limit is reached
+* Don't reveal local time and synchronisation state in client packets
+* Don't keep client sockets open for longer than necessary
+* Ignore poll in KoD RATE packets as ntpd doesn't always set it correctly
+* Warn when using keys shorter than 80 bits
+* Add keygen command to generate random keys easily
+* Add serverstats command to report NTP and command packet statistics
+
+Bug fixes
+---------
+* Fix clock correction after making step on Mac OS X
+* Fix building on Solaris
+
+New in version 2.2.1
+====================
+
+Security fixes
+--------------
+* Restrict authentication of NTP server/peer to specified key (CVE-2016-1567)
+
 New in version 2.2
 ==================
 
@@ -12,6 +264,7 @@ Enhancements
 * Add dynamic drift removal on Mac OS X
 * Add support for setting real-time priority on Mac OS X
 * Add maxdistance directive to limit source selection by root distance
+  (3 seconds by default)
 * Add refresh command to get new addresses of NTP sources
 * Allow wildcard patterns in include directive
 * Restore time from driftfile with -s option if later than RTC time
@@ -23,7 +276,7 @@ Enhancements
 
 Bug fixes
 ---------
-* Fix building on Solaris
+* Fix building on NetBSD, Solaris
 * Restore time from driftfile with -s option if reading RTC failed
 
 Removed features

README

@@ -4,7 +4,7 @@ What is chrony?
 ===============
 
 chrony is a versatile implementation of the Network Time Protocol (NTP).
-It can synchronize the system clock with NTP servers, reference clocks
+It can synchronise the system clock with NTP servers, reference clocks
 (e.g. GPS receiver), and manual input using wristwatch and keyboard.
 It can also operate as an NTPv4 (RFC 5905) server and peer to provide
 a time service to other computers in the network.
@@ -14,10 +14,10 @@ intermittent network connections, heavily congested networks, changing
 temperatures (ordinary computer clocks are sensitive to temperature),
 and systems that do not run continuosly, or run on a virtual machine.
 
-Typical accuracy between two machines on a LAN is in tens, or a few
-hundreds, of microseconds; over the Internet, accuracy is typically
-within a few milliseconds.  With a good hardware reference clock
-sub-microsecond accuracy is possible.
+Typical accuracy between two machines synchronised over the Internet is
+within a few milliseconds; on a LAN, accuracy is typically in tens of
+microseconds.  With hardware timestamping, or a hardware reference clock,
+sub-microsecond accuracy may be possible.
 
 Two programs are included in chrony, chronyd is a daemon that can be
 started at boot time and chronyc is a command-line interface program
@@ -27,7 +27,7 @@ operating parameters whilst it is running.
 What will chrony run on?
 ========================
 
-The software is known to work on Linux, FreeBSD, NetBSD, Mac OS X and
+The software is known to work on Linux, FreeBSD, NetBSD, macOS and
 Solaris.  Closely related systems may work too.  Any other system will
 likely require a porting exercise.  You would need to start from one
 of the existing system-specific drivers and look into the quirks of
@@ -37,23 +37,19 @@ How do I set it up?
 ===================
 
 The file INSTALL gives instructions.  On supported systems the
-compilation process should be automatic.
-
-You will need an ANSI C compiler -- gcc is recommended.
-
-The manual (in texinfo and text formats) describes how to set the
-software up for the less straightforward cases.
+compilation process should be automatic.  You will need a C compiler,
+e.g. gcc or clang.
 
 What documentation is there?
 ============================
 
-A manual is supplied in Texinfo format (chrony.texi) and
-ready-formatted plain text (chrony.txt) in the distribution.
+The distribution includes manual pages and a document containing
+Frequently Asked Questions (FAQ).
 
-There is also information available on the chrony web pages, accessible
+The documentation is also available on the chrony web pages, accessible
 through the URL 
 
-    http://chrony.tuxfamily.org/
+    https://chrony.tuxfamily.org/
 
 Where are new versions announced?
 =================================
@@ -84,150 +80,86 @@ chrony-dev-request@chrony.tuxfamily.org
 
 as applicable.
 
+When you are reporting a bug, please send us all the information you can.
+Unfortunately, chrony has proven to be one of those programs where it is very
+difficult to reproduce bugs in a different environment. So we may have to
+interact with you quite a lot to obtain enough extra logging and tracing to
+pin-point the problem in some cases. Please be patient and plan for this!
+
 License
 =======
 
 chrony is distributed under the GNU General Public License version 2.
 
-
-Author
-======
+Authors
+=======
 
 Richard P. Curnow <rc@rc0.org.uk>
-
-
-Maintainers
-===========
-
 Miroslav Lichvar <mlichvar@redhat.com>
 
-
 Acknowledgements
 ================
 
+In writing the chronyd program, extensive use has been made of RFC 1305
+and RFC 5905, written by David Mills. The source code of the NTP reference
+implementation has been used to check the details of the protocol.
+
 The following people have provided patches and other major contributions
 to the program :
 
+Lonnie Abelbeck <lonnie@abelbeck.com>
 Benny Lyne Amorsen <benny@amorsen.dk>
-    Patch to add minstratum option
-
 Andrew Bishop <amb@gedanken.demon.co.uk>
-    Fixes for bugs in logging when in daemon mode
-    Fixes for compiler warnings
-    Robustness improvements for drift file
-    Improve installation (directory checking etc)
-    Entries in contrib directory
-    Improvements to 'sources' and 'sourcestats' output from chronyc
-    Improvements to documentation
-    Investigation of required dosynctodr behaviour for various Solaris
-      versions.
-
+Vincent Blut <vincent.debian@free.fr>
 Stephan I. Boettcher <stephan@nevis1.columbia.edu>
-    Entries in contrib directory
-
+David Bohman <debohman@gmail.com>
+Goswin Brederlow <brederlo@informatik.uni-tuebingen.de>
+Leigh Brown <leigh@solinno.co.uk>
 Erik Bryer <ebryer@spots.ab.ca>
-    Entries in contrib directory
-
+Jonathan Cameron <jic23@cam.ac.uk>
 Bryan Christianson <bryan@whatroute.net>
-    Support for Mac OS X
-
 Juliusz Chroboczek <jch@pps.jussieu.fr>
-    Fix install rule in Makefile if chronyd file is in use.
-
+Christian Ehrhardt <christian.ehrhardt@canonical.com>
 Paul Elliott <pelliott@io.com>
-    DNSchrony (in contrib directory), a tool for handling NTP servers
-    with variable IP addresses.
-
+Stefan R. Filipek <srfilipek@gmail.com>
 Mike Fleetwood <mike@rockover.demon.co.uk>
-    Fixes for compiler warnings
-
 Alexander Gretencord <arutha@gmx.de>
-    Changes to installation directory system to make it easier for
-    package builders.
-
 Andrew Griffiths <agriffit@redhat.com>
-    Patch to add support for seccomp filter
-
 Walter Haidinger <walter.haidinger@gmx.at>
-    Providing me with login access to a Linux installation where v1.12
-    wouldn't compile, so I could develop the fixes for v1.13.  Also, for
-    providing the disc space so I can keep an independent backup of the
-    sources.
-
 Juergen Hannken-Illjes <hannken@eis.cs.tu-bs.de>
-    Port to NetBSD
-
 John Hasler <john@dhh.gt.org>
-    Project and website at tuxfamily.org
-    Changes to support 64 bit machines (i.e. those where
-      sizeof(unsigned long) > 4)
-    Bug fix to initstepslew directive
-    Fix to remove potential buffer overrun errors.
-    Memory locking and real-time scheduler support
-    Fix fault where chronyd enters an endless loop
-
 Tjalling Hattink <t.hattink@fugro.nl>
-    Fix scheduler to allow stepping clock from timeout handler
-    Patch to take leap second in PPS refclock from locked source
-    Patch to make reading of RTC for initial trim more reliable
-
 Liam Hatton <me@liamhatton.com>
-    Advice on configuring for Linux on PPC
-
 Jachym Holecek <jakym@volny.cz>
-    Patch to make Linux real time clock work with devfs
-
 Håkan Johansson <f96hajo@chalmers.se>
-    Patch to avoid large values in sources and sourcestats output
-
 Jim Knoble <jmknoble@pobox.com>
-    Fixes for compiler warnings
-
 Antti Jrvinen <costello@iki.fi>
-    Advice on configuring for BSD/386
-
-Miroslav Lichvar <mlichvar@redhat.com>
-    Reference clock support
-    IPv6 support
-    Linux capabilities support
-    Leap second support
-    Improved source selection
-    Improved sample history trimming
-    Improved polling interval adjustment
-    Improved stability with temporary asymmetric delays
-    Temperature compensation
-    Many other bug fixes and improvements
-
+Eric Lammerts <eric@lammerts.org>
+Stefan Lucke <stefan@lucke.in-berlin.de>
+Victor Lum <viclum@vanu.com>
+Kevin Lyda <kevin@ie.suberic.net>
+Paul Menzel <paulepanter@users.sourceforge.net>
+Vladimir Michl <vladimir.michl@seznam.cz>
 Victor Moroz <vim@prv.adlum.ru>
-    Patch to support Linux with HZ!=100
-
 Kalle Olavi Niemitalo  <tosi@stekt.oulu.fi>
-    acquisitionport support
-
 Frank Otto <sandwichmacher@web.de>
-    Handling arbitrary HZ values
-
+Denny Page <dennypage@me.com>
+Chris Perl <cperl@janestreet.com>
 Gautier PHILIPPON <gautier.philippon@ensimag.grenoble-inp.fr>
-    Patch to add refresh command to chronyc
-
 Andreas Piesk <apiesk@virbus.de>
-    Patch to make chronyc use the readline library if available
-
+Andreas Steinmetz <ast@domdv.de>
+NAKAMURA Takumi <takumi@ps.sakura.ne.jp>
 Timo Teras <timo.teras@iki.fi>
-    Patch to reply correctly on multihomed hosts
-
+Bill Unruh <unruh@physics.ubc.ca>
+Stephen Wadeley <swadeley@redhat.com>
+Bernhard Weiss <lisnablagh@web.de>
 Wolfgang Weisselberg <weissel@netcologne.de>
-    Entries in contrib directory
-
+Bernhard M. Wiedemann <bwiedemann@suse.de>
+Joachim Wiedorn <ad_debian@joonet.de>
 Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
-    Many robustness and security improvements
-    
-Ulrich Windl <ulrich.windl@rz.uni-regensburg.de> for the
-    Providing me with information about the Linux 2.2 kernel
-    functionality compared to 2.0.
-
+Ulrich Windl <ulrich.windl@rz.uni-regensburg.de>
 Doug Woodward <dougw@whistler.com>
-    Advice on configuring for Solaris 2.8 on x86
+Thomas Zajic <zlatko@zlatko.fdns.net>
 
-Many other people have contributed bug reports and suggestions.  I'm
-sorry I can't identify all of you individually.
+Many other people have contributed bug reports and suggestions.  We are sorry
+we cannot identify all of you individually.

addressing.h

@@ -30,27 +30,36 @@
 #include "sysincl.h"
 
 /* This type is used to represent an IPv4 address or IPv6 address.
+   Addresses which are not resolved yet can be represented with an ID.
    All parts are in HOST order, NOT network order. */
 
 #define IPADDR_UNSPEC 0
 #define IPADDR_INET4 1
 #define IPADDR_INET6 2
+#define IPADDR_ID 3
 
 typedef struct {
   union { 
     uint32_t in4;
     uint8_t in6[16];
+    uint32_t id;
   } addr;
   uint16_t family;
+  uint16_t _pad;
 } IPAddr;
 
 typedef struct {
   IPAddr ip_addr;
-  unsigned short port;
-} NTP_Remote_Address;
+  uint16_t port;
+} IPSockAddr;
+
+typedef IPSockAddr NTP_Remote_Address;
+
+#define INVALID_IF_INDEX -1
 
 typedef struct {
   IPAddr ip_addr;
+  int if_index;
   int sock_fd;
 } NTP_Local_Address;
 

addrfilt.c

@@ -62,7 +62,7 @@ split_ip6(IPAddr *ip, uint32_t *dst)
   int i;
 
   for (i = 0; i < 4; i++)
-    dst[i] = ip->addr.in6[i * 4 + 0] << 24 |
+    dst[i] = (uint32_t)ip->addr.in6[i * 4 + 0] << 24 |
              ip->addr.in6[i * 4 + 1] << 16 |
              ip->addr.in6[i * 4 + 2] << 8 |
              ip->addr.in6[i * 4 + 3];
@@ -247,6 +247,8 @@ set_subnet_(ADF_AuthTable table,
           set_subnet(&table->base6, ip6, 4, 0, new_state, delete_children) == ADF_SUCCESS)
         return ADF_SUCCESS;
       break;
+    default:
+      break;
   }
 
   return ADF_BADSUBNET;
@@ -359,9 +361,9 @@ ADF_IsAllowed(ADF_AuthTable table,
     case IPADDR_INET6:
       split_ip6(ip_addr, ip6);
       return check_ip_in_node(&table->base6, ip6);
+    default:
+      return 0;
   }
-
-  return 0;
 }
 
 /* ================================================== */
@@ -401,117 +403,3 @@ ADF_IsAnyAllowed(ADF_AuthTable table, int family)
       return 0;
   }
 }
-
-/* ================================================== */
-
-#if defined TEST
-
-static void print_node(TableNode *node, uint32_t *addr, int ip_len, int shift, int subnet_bits)
-{
-  uint32_t new_addr[4];
-  int i;
-  TableNode *sub_node;
-
-  for (i=0; i<subnet_bits; i++) putchar(' ');
-
-  if (ip_len == 1)
-      printf("%d.%d.%d.%d",
-          ((addr[0] >> 24) & 255),
-          ((addr[0] >> 16) & 255),
-          ((addr[0] >>  8) & 255),
-          ((addr[0]      ) & 255));
-  else {
-    for (i=0; i<4; i++) {
-      if (addr[i])
-        printf("%d.%d.%d.%d",
-            ((addr[i] >> 24) & 255),
-            ((addr[i] >> 16) & 255),
-            ((addr[i] >>  8) & 255),
-            ((addr[i]      ) & 255));
-      putchar(i < 3 ? ':' : '\0');
-    }
-  }
-  printf("/%d : %s\n",
-         subnet_bits,
-         (node->state == ALLOW) ? "allow" :
-         (node->state == DENY)  ? "deny" : "as parent");
-  if (node->extended) {
-    for (i=0; i<16; i++) {
-      sub_node = &(node->extended[i]);
-      new_addr[0] = addr[0];
-      new_addr[1] = addr[1];
-      new_addr[2] = addr[2];
-      new_addr[3] = addr[3];
-      new_addr[ip_len - 1 - shift / 32] |= ((uint32_t)i << (shift % 32));
-      print_node(sub_node, new_addr, ip_len, shift - 4, subnet_bits + 4);
-    }
-  }
-}
-
-
-static void print_table(ADF_AuthTable table)
-{
-  uint32_t addr[4];
-
-  memset(addr, 0, sizeof (addr));
-  printf("IPv4 table:\n");
-  print_node(&table->base4, addr, 1, 28, 0);
-
-  memset(addr, 0, sizeof (addr));
-  printf("IPv6 table:\n");
-  print_node(&table->base6, addr, 4, 124, 0);
-}
-
-/* ================================================== */
-
-int main (int argc, char **argv)
-{
-  IPAddr ip;
-  ADF_AuthTable table;
-  table = ADF_CreateTable();
-
-  ip.family = IPADDR_INET4;
-
-  ip.addr.in4 = 0x7e800000;
-  ADF_Allow(table, &ip, 9);
-  ip.addr.in4 = 0x7ecc0000;
-  ADF_Deny(table, &ip, 14);
-#if 0
-  ip.addr.in4 = 0x7f000001;
-  ADF_Deny(table, &ip, 32);
-  ip.addr.in4 = 0x7f000000;
-  ADF_Allow(table, &ip, 8);
-#endif
-
-  printf("allowed: %d\n", ADF_IsAllowed(table, &ip));
-  ip.addr.in4 ^= 1;
-  printf("allowed: %d\n", ADF_IsAllowed(table, &ip));
-
-  ip.family = IPADDR_INET6;
-
-  memcpy(ip.addr.in6, "abcdefghijklmnop", 16);
-  ADF_Deny(table, &ip, 66);
-  ADF_Allow(table, &ip, 59);
-
-  memcpy(ip.addr.in6, "xbcdefghijklmnop", 16);
-  ADF_Deny(table, &ip, 128);
-  ip.addr.in6[15] ^= 3;
-  ADF_Allow(table, &ip, 127);
-
-  printf("allowed: %d\n", ADF_IsAllowed(table, &ip));
-  ip.addr.in4 ^= 1;
-  printf("allowed: %d\n", ADF_IsAllowed(table, &ip));
-
-  print_table(table);
-
-  ADF_DestroyTable(table);
-  return 0;
-}
-
-
-
-#endif /* defined TEST */
-
-
-
-

array.c

@@ -66,8 +66,6 @@ ARR_DestroyInstance(ARR_Instance array)
 static void
 realloc_array(ARR_Instance array, unsigned int min_size)
 {
-  size_t data_size;
-
   assert(min_size <= 2 * min_size);
   if (array->allocated >= min_size && array->allocated <= 2 * min_size)
     return;
@@ -79,10 +77,7 @@ realloc_array(ARR_Instance array, unsigned int min_size)
     array->allocated = min_size;
   }
 
-  data_size = (size_t)array->elem_size * array->allocated;
-  assert(data_size / array->elem_size == array->allocated);
-
-  array->data = Realloc(array->data, data_size);
+  array->data = Realloc2(array->data, array->allocated, array->elem_size);
 }
 
 void *
@@ -103,6 +98,12 @@ ARR_GetElement(ARR_Instance array, unsigned int index)
 void *
 ARR_GetElements(ARR_Instance array)
 {
+  /* Return a non-NULL pointer when the array has zero size */
+  if (!array->data) {
+    assert(!array->used);
+    return array;
+  }
+
   return array->data;
 }
 

candm.h

@@ -91,18 +91,27 @@
 #define REQ_SMOOTHING 51
 #define REQ_SMOOTHTIME 52
 #define REQ_REFRESH 53
-#define N_REQUEST_TYPES 54
+#define REQ_SERVER_STATS 54
+#define REQ_CLIENT_ACCESSES_BY_INDEX2 55
+#define REQ_LOCAL2 56
+#define REQ_NTP_DATA 57
+#define REQ_ADD_SERVER2 58
+#define REQ_ADD_PEER2 59
+#define REQ_ADD_SERVER3 60
+#define REQ_ADD_PEER3 61
+#define REQ_SHUTDOWN 62
+#define REQ_ONOFFLINE 63
+#define REQ_ADD_SOURCE 64
+#define REQ_NTP_SOURCE_NAME 65
+#define REQ_RESET 66
+#define N_REQUEST_TYPES 67
 
-/* Special utoken value used to log on with first exchange being the
-   password.  (This time value has long since gone by) */
-#define SPECIAL_UTOKEN 0x10101010
-
-/* Structure used to exchange timevals independent on size of time_t */
+/* Structure used to exchange timespecs independent of time_t size */
 typedef struct {
   uint32_t tv_sec_high;
   uint32_t tv_sec_low;
   uint32_t tv_nsec;
-} Timeval;
+} Timespec;
 
 /* This is used in tv_sec_high for 32-bit timestamps */
 #define TV_NOHIGHSEC 0x7fffffff
@@ -201,18 +210,20 @@ typedef struct {
 } REQ_Modify_Makestep;
 
 typedef struct {
-  Timeval ts;
+  Timespec ts;
   int32_t EOR;
 } REQ_Logon;
 
 typedef struct {
-  Timeval ts;
+  Timespec ts;
   int32_t EOR;
 } REQ_Settime;
 
 typedef struct {
   int32_t on_off;
   int32_t stratum;
+  Float distance;
+  int32_t orphan;
   int32_t EOR;
 } REQ_Local;
 
@@ -237,23 +248,47 @@ typedef struct {
   int32_t EOR;
 } REQ_Ac_Check;
 
+/* Source types in NTP source requests */
+#define REQ_ADDSRC_SERVER 1
+#define REQ_ADDSRC_PEER 2
+#define REQ_ADDSRC_POOL 3
+
 /* Flags used in NTP source requests */
 #define REQ_ADDSRC_ONLINE 0x1
 #define REQ_ADDSRC_AUTOOFFLINE 0x2
 #define REQ_ADDSRC_IBURST 0x4
 #define REQ_ADDSRC_PREFER 0x8
 #define REQ_ADDSRC_NOSELECT 0x10
+#define REQ_ADDSRC_TRUST 0x20
+#define REQ_ADDSRC_REQUIRE 0x40
+#define REQ_ADDSRC_INTERLEAVED 0x80
+#define REQ_ADDSRC_BURST 0x100
+#define REQ_ADDSRC_NTS 0x200
 
 typedef struct {
-  IPAddr ip_addr;
+  uint32_t type;
+  int8_t name[256];
   uint32_t port;
   int32_t minpoll;
   int32_t maxpoll;
   int32_t presend_minpoll;
+  uint32_t min_stratum;
+  uint32_t poll_target;
+  uint32_t version;
+  uint32_t max_sources;
+  int32_t min_samples;
+  int32_t max_samples;
   uint32_t authkey;
+  uint32_t nts_port;
   Float max_delay;
   Float max_delay_ratio;
+  Float max_delay_dev_ratio;
+  Float min_delay;
+  Float asymmetry;
+  Float offset;
   uint32_t flags;
+  int32_t filter_length;
+  uint32_t reserved[3];
   int32_t EOR;
 } REQ_NTP_Source;
 
@@ -284,7 +319,7 @@ typedef struct {
 
 typedef struct {
   uint32_t first_index;
-  uint32_t n_indices;
+  uint32_t n_clients;
   int32_t EOR;
 } REQ_ClientAccessesByIndex;
 
@@ -306,6 +341,16 @@ typedef struct {
   int32_t EOR;
 } REQ_SmoothTime;
 
+typedef struct {
+  IPAddr ip_addr;
+  int32_t EOR;
+} REQ_NTPData;
+
+typedef struct {
+  IPAddr ip_addr;
+  int32_t EOR;
+} REQ_NTPSourceName;
+
 /* ================================================== */
 
 #define PKT_TYPE_CMD_REQUEST 1
@@ -335,9 +380,16 @@ typedef struct {
 
    Version 6 : added padding to requests to prevent amplification attack,
    changed maximum number of samples in manual list to 16, new commands: modify
-   makestep, smoothing report, smoothtime command
+   makestep, smoothing, smoothtime
 
-   Authentication was removed later in version 6.
+   Support for authentication was removed later in version 6 of the protocol
+   and commands that required authentication are allowed only locally over Unix
+   domain socket.
+
+   Version 6 (no authentication) : changed format of client accesses by index
+   (using new request/reply types) and manual timestamp, added new fields and
+   flags to NTP source request and report, made length of manual list constant,
+   added new commands: ntpdata, refresh, serverstats, shutdown
  */
 
 #define PROTO_VERSION_NUMBER 6
@@ -351,7 +403,7 @@ typedef struct {
 #define PROTO_VERSION_PADDING 6
 
 /* The maximum length of padding in request packet, currently
-   defined by CLIENT_ACCESSES_BY_INDEX and MANUAL_LIST */
+   defined by MANUAL_LIST */
 #define MAX_PADDING_LENGTH 396
 
 /* ================================================== */
@@ -400,6 +452,8 @@ typedef struct {
     REQ_ManualDelete manual_delete;
     REQ_ReselectDistance reselect_distance;
     REQ_SmoothTime smoothtime;
+    REQ_NTPData ntp_data;
+    REQ_NTPData ntp_source_name;
   } data; /* Command specific parameters */
 
   /* Padding used to prevent traffic amplification.  It only defines the
@@ -431,7 +485,13 @@ typedef struct {
 #define RPY_MANUAL_LIST 11
 #define RPY_ACTIVITY 12
 #define RPY_SMOOTHING 13
-#define N_REPLY_TYPES 14
+#define RPY_SERVER_STATS 14
+#define RPY_CLIENT_ACCESSES_BY_INDEX2 15
+#define RPY_NTP_DATA 16
+#define RPY_MANUAL_TIMESTAMP2 17
+#define RPY_MANUAL_LIST2 18
+#define RPY_NTP_SOURCE_NAME 19
+#define N_REPLY_TYPES 20
 
 /* Status codes */
 #define STT_SUCCESS 0
@@ -455,6 +515,7 @@ typedef struct {
 #define STT_INVALIDAF 17
 #define STT_BADPKTVERSION 18
 #define STT_BADPKTLENGTH 19
+#define STT_INVALIDNAME 21
 
 typedef struct {
   int32_t EOR;
@@ -478,6 +539,8 @@ typedef struct {
 
 #define RPY_SD_FLAG_NOSELECT 0x1
 #define RPY_SD_FLAG_PREFER 0x2
+#define RPY_SD_FLAG_TRUST 0x4
+#define RPY_SD_FLAG_REQUIRE 0x8
 
 typedef struct {
   IPAddr ip_addr;
@@ -499,7 +562,7 @@ typedef struct {
   IPAddr ip_addr;
   uint16_t stratum;
   uint16_t leap_status;
-  Timeval ref_time;
+  Timespec ref_time;
   Float current_correction;
   Float last_offset;
   Float rms_offset;
@@ -527,7 +590,7 @@ typedef struct {
 } RPY_Sourcestats;
 
 typedef struct {
-  Timeval ref_time;
+  Timespec ref_time;
   uint16_t n_samples;
   uint16_t n_runs;
   uint32_t span_seconds;
@@ -537,7 +600,7 @@ typedef struct {
 } RPY_Rtc;
 
 typedef struct {
-  uint32_t centiseconds;
+  Float offset;
   Float dfreq_ppm;
   Float new_afreq_ppm;
   int32_t EOR;
@@ -545,11 +608,14 @@ typedef struct {
 
 typedef struct {
   IPAddr ip;
-  uint32_t client_hits;
-  uint32_t peer_hits;
-  uint32_t cmd_hits_auth;
-  uint32_t cmd_hits_normal;
-  uint32_t cmd_hits_bad;
+  uint32_t ntp_hits;
+  uint32_t cmd_hits;
+  uint32_t ntp_drops;
+  uint32_t cmd_drops;
+  int8_t ntp_interval;
+  int8_t cmd_interval;
+  int8_t ntp_timeout_interval;
+  int8_t pad;
   uint32_t last_ntp_hit_ago;
   uint32_t last_cmd_hit_ago;
 } RPY_ClientAccesses_Client;
@@ -562,10 +628,19 @@ typedef struct {
   int32_t EOR;
 } RPY_ClientAccessesByIndex;
 
+typedef struct {
+  uint32_t ntp_hits;
+  uint32_t cmd_hits;
+  uint32_t ntp_drops;
+  uint32_t cmd_drops;
+  uint32_t log_drops;
+  int32_t EOR;
+} RPY_ServerStats;
+
 #define MAX_MANUAL_LIST_SAMPLES 16
 
 typedef struct {
-  Timeval when;
+  Timespec when;
   Float slewed_offset;
   Float orig_offset;
   Float residual;
@@ -599,6 +674,44 @@ typedef struct {
   int32_t EOR;
 } RPY_Smoothing;
 
+#define RPY_NTP_FLAGS_TESTS 0x3ff
+#define RPY_NTP_FLAG_INTERLEAVED 0x4000
+#define RPY_NTP_FLAG_AUTHENTICATED 0x8000
+
+typedef struct {
+  IPAddr remote_addr;
+  IPAddr local_addr;
+  uint16_t remote_port;
+  uint8_t leap;
+  uint8_t version;
+  uint8_t mode;
+  uint8_t stratum;
+  int8_t poll;
+  int8_t precision;
+  Float root_delay;
+  Float root_dispersion;
+  uint32_t ref_id;
+  Timespec ref_time;
+  Float offset;
+  Float peer_delay;
+  Float peer_dispersion;
+  Float response_time;
+  Float jitter_asymmetry;
+  uint16_t flags;
+  uint8_t tx_tss_char;
+  uint8_t rx_tss_char;
+  uint32_t total_tx_count;
+  uint32_t total_rx_count;
+  uint32_t total_valid_count;
+  uint32_t reserved[4];
+  int32_t EOR;
+} RPY_NTPData;
+
+typedef struct {
+  int8_t name[256];
+  int32_t EOR;
+} RPY_NTPSourceName;
+
 typedef struct {
   uint8_t version;
   uint8_t pkt_type;
@@ -623,9 +736,12 @@ typedef struct {
     RPY_Sourcestats sourcestats;
     RPY_Rtc rtc;
     RPY_ClientAccessesByIndex client_accesses_by_index;
+    RPY_ServerStats server_stats;
     RPY_ManualList manual_list;
     RPY_Activity activity;
     RPY_Smoothing smoothing;
+    RPY_NTPData ntp_data;
+    RPY_NTPSourceName ntp_source_name;
   } data; /* Reply specific parameters */
 
 } CMD_Reply;

chrony.conf.5.in

@@ -1,67 +0,0 @@
-.TH chrony.conf 5 "@MAN_DATE@" "chrony @VERSION@" "Configuration Files"
-.SH NAME
-chrony.conf \- chronyd configuration file
-
-.SH SYNOPSIS
-.B @SYSCONFDIR@/chrony.conf
-
-.SH DESCRIPTION
-\fIchrony\fR is a pair of programs for maintaining the accuracy of computer
-clocks. \fIchronyd\fR is a background daemon program that can be started at
-boot time.
-
-Assuming that you have found some servers, you need to set up a
-configuration file to run \fIchrony\fR.  The (compiled-in) default location
-for this file is \fB@SYSCONFDIR@/chrony.conf\fR.  Assuming that your NTP
-servers are called `foo.example.net', `bar.example.net' and `baz.example.net',
-your \fBchrony.conf\fR file could contain as a minimum
-
-.EX
-     server foo.example.net
-     server bar.example.net
-     server baz.example.net
-.EE
-
-However, you will probably want to include some of the other directives
-described in detail in the documentation supplied with the distribution
-(\fIchrony.txt\fR and \fIchrony.texi\fR). The following directives may be
-particularly useful : `driftfile',  `makestep', `rtcsync'.  Also, the `iburst'
-server option is useful to speed up the initial synchronization.  The smallest
-useful configuration file would look something like
-
-.EX
-     server foo.example.net iburst
-     server bar.example.net iburst
-     server baz.example.net iburst
-     driftfile @CHRONYVARDIR@/drift
-     makestep 1.0 3
-     rtcsync
-.EE
-
-When using a pool of NTP servers (one name is used for multiple servers which
-may change over time), it's better to specify them with the `pool' directive
-instead of multiple `server' directives.  The configuration file could in this
-case look like
-
-.EX
-     pool pool.ntp.org iburst
-     driftfile @CHRONYVARDIR@/drift
-     makestep 1.0 3
-     rtcsync
-.EE
-
-.SH "SEE ALSO"
-.BR chronyc(1),
-.BR chronyd(8)
-
-.I http://chrony.tuxfamily.org/
-
-.SH AUTHOR
-Richard Curnow <rc@rc0.org.uk>
-
-This man-page was written by Jan Schaumann <jschauma@netmeister.org> as part of "The Missing
-Man Pages Project".  Please see \fIhttp://www.netmeister.org/misc/m2p2/index.html\fR
-for details.
-
-The complete chrony documentation is supplied in texinfo format.
-

chronyc.1.in

@@ -1,74 +0,0 @@
-.TH CHRONYC 1 "@MAN_DATE@" "chrony @VERSION@" "User's Manual"
-.SH NAME
-chronyc \- command-line interface for chronyd
-
-.SH SYNOPSIS
-.B chronyc
-[\fIOPTIONS\fR]
-
-.SH DESCRIPTION
-\fIchrony\fR is a pair of programs for maintaining the accuracy of computer
-clocks.
-
-\fBchronyc\fR is a command-line interface program which can be used to
-monitor \fIchronyd\fR's performance and to change various operating
-parameters whilst it is running.
-
-.SH USAGE
-A detailed description of all commands supported by \fBchronyc\fR is available
-via the documentation supplied with the distribution (\fIchrony.txt\fR and
-\fIchrony.texi\fR).
-
-.SH OPTIONS
-A summary of the options supported by \fBchronyc\fR is included below.
-
-.TP
-\fB\-h\fR \fIhostname\fR
-specify hostname or comma-separated list of addresses
-(default @CHRONYSOCKDIR@/chronyd.sock,127.0.0.1,::1)
-.TP
-\fB\-p\fR \fIport-number\fR
-specify port-number
-.TP
-\fB\-n\fR
-display raw IP addresses (don't attempt to look up hostnames)
-.TP
-\fB\-d\fR
-print debugging messages (if compiled with debugging support)
-.TP
-\fB\-4\fR
-resolve hostnames only to IPv4 addresses
-.TP
-\fB\-6\fR
-resolve hostnames only to IPv6 addresses
-.TP
-\fB\-m\fR
-allow multiple commands to be specified on the command line.  Each argument
-will be interpreted as a whole command.
-.TP
-\fB\-f\fR \fIconf-file\fR
-this option is ignored and is provided only for compatibility.
-.TP
-\fB\-a\fR
-this option is ignored and is provided only for compatibility.
-.TP
-\fIcommand\fR
-specify command.  If no command is given, chronyc will read commands
-interactively.
-
-.SH BUGS
-To report bugs, please visit \fIhttp://chrony.tuxfamily.org\fR
-
-.SH "SEE ALSO"
-.BR chronyd(8)
-
-.I http://chrony.tuxfamily.org/
-
-.SH AUTHOR
-Richard Curnow <rc@rc0.org.uk>
-
-This man-page was written by Jan Schaumann <jschauma@netmeister.org> as part of "The Missing
-Man Pages Project".  Please see \fIhttp://www.netmeister.org/misc/m2p2/index.html\fR
-for details.
-
-The complete chrony documentation is supplied in texinfo format.

chronyd.8.in

@@ -1,156 +0,0 @@
-.TH CHRONYD 8 "@MAN_DATE@" "chrony @VERSION@" "System Administration"
-.SH NAME
-chronyd \- chrony background daemon
-
-.SH SYNOPSIS
-.B chronyd
-[\fIOPTIONS\fR] [\fIconfiguration commands\fR]
-
-.SH DESCRIPTION
-\fIchrony\fR is a pair of programs for maintaining the accuracy of computer
-clocks. \fBchronyd\fR is a background daemon program that can be started at boot
-time.
-
-\fBchronyd\fR is a daemon which runs in background on the
-system.  It obtains measurements (e.g. via the network) of the
-system's offset relative to other systems, and adjusts the system
-time accordingly.  For isolated systems, the user can periodically
-enter the correct time by hand (using \fIchronyc\fR).  In either case,
-\fBchronyd\fR determines the rate at which the computer
-gains or loses time, and compensates for this.
-
-.SH USAGE
-\fBchronyd\fR is usually started at boot-time and requires superuser
-privileges.
-
-If \fBchronyd\fR has been installed to its default location
-\fI@SBINDIR@/chronyd\fR, starting it is simply a matter of entering the
-command:
-
-\fI@SBINDIR@/chronyd\fR
-
-Information messages and warnings will be logged to syslog.
-
-If no configuration commands are specified on the command line,
-\fBchronyd\fR will read the commands from the configuration file
-(default \fI@SYSCONFDIR@/chrony.conf\fR).
-
-.SH OPTIONS
-A summary of the options supported by \fBchronyd\fR is included below.
-
-.TP
-\fB\-P\fR \fIpriority\fR
-On Linux, this option will select the SCHED_FIFO real-time scheduler at the
-specified priority (which must be between 0 and 100).  On Mac OS X, this
-option must have either a value of 0 (the default) to disable the thread
-time constraint policy or 1 for the policy to be enabled.  Other systems do not
-support this option.
-.TP
-.B \-m
-This option will lock chronyd into RAM so that it will never be paged out.
-This mode is only supported on Linux.
-.TP
-.B \-n
-When run in this mode, the program will not detach itself from the
-terminal.
-.TP
-.B \-d
-When run in this mode, the program will not detach itself from the
-terminal, and all messages will be sent to the terminal instead of
-to syslog.  When \fBchronyd\fR was compiled with debugging support,
-this option can be used twice to print also debugging messages.
-.TP
-\fB\-f\fR \fIconf-file\fR
-This option can be used to specify an alternate location for the
-configuration file (default \fI@SYSCONFDIR@/chrony.conf\fR).
-.TP
-.B \-r
-This option will reload sample histories for each of the servers being used.
-These histories are created by using the \fIdump\fR command in \fIchronyc\fR,
-or by setting the \fIdumponexit\fR directive in the configuration file.  This
-option is useful if you want to stop and restart \fBchronyd\fR briefly for any
-reason, e.g. to install a new version.  However, it should be used only on
-systems where the kernel can maintain clock compensation whilst not under
-\fBchronyd\fR's control (i.e. Linux, FreeBSD, NetBSD and Solaris).
-.TP
-.B \-R
-When this option is used, the \fIinitstepslew\fR directive and the
-\fImakestep\fR directive used with a positive limit will be ignored. This
-option is useful when restarting \fBchronyd\fR and can be used in conjunction
-with the \fB-r\fR option.
-.TP
-.B \-s
-This option will set the system clock from the computer's real-time clock or
-to the last modification time of the file specified by the \fIdriftfile\fR
-directive.  Real-time clocks are supported only on Linux.
-
-If used in conjunction with the \fB-r\fR flag, \fBchronyd\fR will attempt
-to preserve the old samples after setting the system clock from
-the real time clock (RTC).  This can be used to allow \fBchronyd\fR to
-perform long term averaging of the gain or loss rate across system
-reboots, and is useful for dial-up systems that are shut down when
-not in use.  For this to work well, it relies on \fBchronyd\fR having
-been able to determine accurate statistics for the difference
-between the RTC and system clock last time the computer was on.
-
-If the last modification time of the drift file is later than the current time
-and the RTC time, the system time will be set to it to restore the time when
-\fBchronyd\fR was previously stopped.  This is useful on computers that have no
-RTC or the RTC is broken (e.g. it has no battery).
-.TP
-\fB\-u\fR \fIuser\fR
-This option sets the name of the system user to which \fBchronyd\fR will switch
-after start in order to drop root privileges.  It overrides the \fBuser\fR
-directive (default \fB@DEFAULT_USER@\fR).  It may be set to a non-root user
-only when \fBchronyd\fR is compiled with support for Linux capabilities
-(libcap) or on NetBSD with the \fB/dev/clockctl\fR device.
-.TP
-\fB\-F\fR \fIlevel\fR
-This option configures a system call filter when \fBchronyd\fR is compiled with
-support for the Linux secure computing (seccomp) facility. In level 1 the
-process is killed when a forbidden system call is made, in level -1 the SYSSIG
-signal is thrown instead and in level 0 the filter is disabled (default 0).
-.TP
-.B \-q
-When run in this mode, chronyd will set the system clock once
-and exit.  It will not detach from the terminal.
-.TP
-.B \-Q
-This option is similar to \fB\-q\fR, but it will only print the offset and
-not correct the clock.
-.TP
-.B \-v
-This option displays \fBchronyd\fR's version number to the terminal and exits
-.TP
-.B \-4
-Resolve hostnames only to IPv4 addresses and create only IPv4 sockets.
-.TP
-.B \-6
-Resolve hostnames only to IPv6 addresses and create only IPv6 sockets.
-
-.SH FILES
-\fI@SYSCONFDIR@/chrony.conf\fR
-
-.SH BUGS
-To report bugs, please visit \fIhttp://chrony.tuxfamily.org/\fR
-
-.SH "SEE ALSO"
-\fBchronyd\fR is documented in detail in the documentation supplied with the
-distribution (\fIchrony.txt\fR and \fIchrony.texi\fR).
-
-.BR chronyc(1),
-.BR chrony.conf(5),
-.BR hwclock(8),
-.BR ntpd(8)
-
-.I http://chrony.tuxfamily.org/
-
-.SH AUTHOR
-Richard Curnow <rc@rc0.org.uk>
-
-This man-page was written by Jan Schaumann <jschauma@netmeister.org> as part
-of "The Missing Man Pages Project".  Please see
-\fIhttp://www.netmeister.org/misc/m2p2/index.html\fR for details.
-
-The complete chrony documentation is supplied in texinfo format.
-

clientlog.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2009
+ * Copyright (C) Miroslav Lichvar  2009, 2015-2017
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -34,117 +34,271 @@
 #include "config.h"
 
 #include "sysincl.h"
+
+#include "array.h"
 #include "clientlog.h"
 #include "conf.h"
 #include "memory.h"
+#include "ntp.h"
 #include "reports.h"
 #include "util.h"
 #include "logging.h"
 
-/* Number of bits of address per layer of the table.  This value has
-   been chosen on the basis that a server will predominantly be serving
-   a lot of hosts in a few subnets, rather than a few hosts scattered
-   across many subnets. */
-
-#define NBITS 8
-
-/* Number of entries in each subtable */
-#define TABLE_SIZE (1UL<<NBITS)
-
-typedef struct _Node {
+typedef struct {
   IPAddr ip_addr;
-  unsigned long client_hits;
-  unsigned long peer_hits;
-  unsigned long cmd_hits_bad;
-  unsigned long cmd_hits_normal;
-  unsigned long cmd_hits_auth;
-  time_t last_ntp_hit;
-  time_t last_cmd_hit;
-} Node;
+  uint32_t last_ntp_hit;
+  uint32_t last_cmd_hit;
+  uint32_t ntp_hits;
+  uint32_t cmd_hits;
+  uint16_t ntp_drops;
+  uint16_t cmd_drops;
+  uint16_t ntp_tokens;
+  uint16_t cmd_tokens;
+  int8_t ntp_rate;
+  int8_t cmd_rate;
+  int8_t ntp_timeout_rate;
+  uint8_t flags;
+  NTP_int64 ntp_rx_ts;
+  NTP_int64 ntp_tx_ts;
+} Record;
 
-typedef struct _Subnet {
-  void *entry[TABLE_SIZE];
-} Subnet;
+/* Hash table of records, there is a fixed number of records per slot */
+static ARR_Instance records;
 
-/* ================================================== */
+#define SLOT_BITS 4
 
-/* Table for the IPv4 class A subnet */
-static Subnet top_subnet4;
-/* Table for IPv6 */
-static Subnet top_subnet6;
+/* Number of records in one slot of the hash table */
+#define SLOT_SIZE (1U << SLOT_BITS)
 
-/* Table containing pointers directly to all nodes that have been
-   allocated. */
-static Node **nodes = NULL;
+/* Minimum number of slots */
+#define MIN_SLOTS 1
 
-/* Number of nodes actually in the table. */
-static int n_nodes = 0;
+/* Maximum number of slots, this is a hard limit */
+#define MAX_SLOTS (1U << (24 - SLOT_BITS))
 
-/* Number of entries for which the table has been sized. */
-static int max_nodes = 0;
+/* Number of slots in the hash table */
+static unsigned int slots;
+
+/* Maximum number of slots given memory allocation limit */
+static unsigned int max_slots;
+
+/* Times of last hits are saved as 32-bit fixed point values */
+#define TS_FRAC 4
+#define INVALID_TS 0
+
+/* Static offset included in conversion to the fixed-point timestamps to
+   randomise their alignment */
+static uint32_t ts_offset;
+
+/* Request rates are saved in the record as 8-bit scaled log2 values */
+#define RATE_SCALE 4
+#define MIN_RATE (-14 * RATE_SCALE)
+#define INVALID_RATE -128
+
+/* Response rates are controlled by token buckets.  The capacity and
+   number of tokens spent on response are determined from configured
+   minimum inverval between responses (in log2) and burst length. */
+
+#define MIN_LIMIT_INTERVAL (-15 - TS_FRAC)
+#define MAX_LIMIT_INTERVAL 12
+#define MIN_LIMIT_BURST 1
+#define MAX_LIMIT_BURST 255
+
+static uint16_t max_ntp_tokens;
+static uint16_t max_cmd_tokens;
+static uint16_t ntp_tokens_per_packet;
+static uint16_t cmd_tokens_per_packet;
+
+/* Reduction of token rates to avoid overflow of 16-bit counters.  Negative
+   shift is used for coarse limiting with intervals shorter than -TS_FRAC. */
+static int ntp_token_shift;
+static int cmd_token_shift;
+
+/* Rates at which responses are randomly allowed (in log2) when the
+   buckets don't have enough tokens.  This is necessary in order to
+   prevent an attacker sending requests with spoofed source address
+   from blocking responses to the address completely. */
+
+#define MIN_LEAK_RATE 1
+#define MAX_LEAK_RATE 4
+
+static int ntp_leak_rate;
+static int cmd_leak_rate;
+
+/* Flag indicating whether the last response was dropped */
+#define FLAG_NTP_DROPPED 0x1
+
+/* NTP limit interval in log2 */
+static int ntp_limit_interval;
 
 /* Flag indicating whether facility is turned on or not */
-static int active = 0;
+static int active;
 
-/* Flag indicating whether memory allocation limit has been reached
-   and no new nodes or subnets should be allocated */
-static int alloc_limit_reached;
+/* Global statistics */
+static uint32_t total_ntp_hits;
+static uint32_t total_cmd_hits;
+static uint32_t total_ntp_drops;
+static uint32_t total_cmd_drops;
+static uint32_t total_record_drops;
 
-static unsigned long alloc_limit;
-static unsigned long alloced;
+#define NSEC_PER_SEC 1000000000U
 
 /* ================================================== */
 
-static void
-split_ip6(IPAddr *ip, uint32_t *dst)
-{
-  int i;
+static int expand_hashtable(void);
 
-  for (i = 0; i < 4; i++)
-    dst[i] = ip->addr.in6[i * 4 + 0] << 24 |
-             ip->addr.in6[i * 4 + 1] << 16 |
-             ip->addr.in6[i * 4 + 2] << 8 |
-             ip->addr.in6[i * 4 + 3];
+/* ================================================== */
+
+static int
+compare_ts(uint32_t x, uint32_t y)
+{
+  if (x == y)
+    return 0;
+  if (y == INVALID_TS)
+    return 1;
+  return (int32_t)(x - y) > 0 ? 1 : -1;
 }
 
 /* ================================================== */
 
-inline static uint32_t
-get_subnet(uint32_t *addr, unsigned int where)
+static Record *
+get_record(IPAddr *ip)
 {
-  int off;
+  unsigned int first, i;
+  time_t last_hit, oldest_hit = 0;
+  Record *record, *oldest_record;
 
-  off = where / 32;
-  where %= 32;
+  if (!active || (ip->family != IPADDR_INET4 && ip->family != IPADDR_INET6))
+    return NULL;
 
-  return (addr[off] >> (32 - NBITS - where)) & ((1UL << NBITS) - 1);
-}
+  while (1) {
+    /* Get index of the first record in the slot */
+    first = UTI_IPToHash(ip) % slots * SLOT_SIZE;
 
-/* ================================================== */
+    for (i = 0, oldest_record = NULL; i < SLOT_SIZE; i++) {
+      record = ARR_GetElement(records, first + i);
 
+      if (!UTI_CompareIPs(ip, &record->ip_addr, NULL))
+        return record;
 
-static void
-clear_subnet(Subnet *subnet)
-{
-  int i;
+      if (record->ip_addr.family == IPADDR_UNSPEC)
+        break;
 
-  for (i=0; i<TABLE_SIZE; i++) {
-    subnet->entry[i] = NULL;
+      last_hit = compare_ts(record->last_ntp_hit, record->last_cmd_hit) > 0 ?
+                 record->last_ntp_hit : record->last_cmd_hit;
+
+      if (!oldest_record || compare_ts(oldest_hit, last_hit) > 0 ||
+          (oldest_hit == last_hit && record->ntp_hits + record->cmd_hits <
+           oldest_record->ntp_hits + oldest_record->cmd_hits)) {
+        oldest_record = record;
+        oldest_hit = last_hit;
+      }
+    }
+
+    /* If the slot still has an empty record, use it */
+    if (record->ip_addr.family == IPADDR_UNSPEC)
+      break;
+
+    /* Resize the table if possible and try again as the new slot may
+       have some empty records */
+    if (expand_hashtable())
+      continue;
+
+    /* There is no other option, replace the oldest record */
+    record = oldest_record;
+    total_record_drops++;
+    break;
   }
+
+  record->ip_addr = *ip;
+  record->last_ntp_hit = record->last_cmd_hit = INVALID_TS;
+  record->ntp_hits = record->cmd_hits = 0;
+  record->ntp_drops = record->cmd_drops = 0;
+  record->ntp_tokens = max_ntp_tokens;
+  record->cmd_tokens = max_cmd_tokens;
+  record->ntp_rate = record->cmd_rate = INVALID_RATE;
+  record->ntp_timeout_rate = INVALID_RATE;
+  record->flags = 0;
+  UTI_ZeroNtp64(&record->ntp_rx_ts);
+  UTI_ZeroNtp64(&record->ntp_tx_ts);
+
+  return record;
+}
+
+/* ================================================== */
+
+static int
+expand_hashtable(void)
+{
+  ARR_Instance old_records;
+  Record *old_record, *new_record;
+  unsigned int i;
+
+  old_records = records;
+
+  if (2 * slots > max_slots)
+    return 0;
+
+  records = ARR_CreateInstance(sizeof (Record));
+
+  slots = MAX(MIN_SLOTS, 2 * slots);
+  assert(slots <= max_slots);
+
+  ARR_SetSize(records, slots * SLOT_SIZE);
+
+  /* Mark all new records as empty */
+  for (i = 0; i < slots * SLOT_SIZE; i++) {
+    new_record = ARR_GetElement(records, i);
+    new_record->ip_addr.family = IPADDR_UNSPEC;
+  }
+
+  if (!old_records)
+    return 1;
+
+  /* Copy old records to the new hash table */
+  for (i = 0; i < ARR_GetSize(old_records); i++) {
+    old_record = ARR_GetElement(old_records, i);
+    if (old_record->ip_addr.family == IPADDR_UNSPEC)
+      continue;
+
+    new_record = get_record(&old_record->ip_addr);
+
+    assert(new_record);
+    *new_record = *old_record;
+  }
+
+  ARR_DestroyInstance(old_records);
+
+  return 1;
 }
 
 /* ================================================== */
 
 static void
-clear_node(Node *node)
+set_bucket_params(int interval, int burst, uint16_t *max_tokens,
+                  uint16_t *tokens_per_packet, int *token_shift)
 {
-  node->client_hits = 0;
-  node->peer_hits = 0;
-  node->cmd_hits_auth = 0;
-  node->cmd_hits_normal = 0;
-  node->cmd_hits_bad = 0;
-  node->last_ntp_hit = (time_t) 0;
-  node->last_cmd_hit = (time_t) 0;
+  interval = CLAMP(MIN_LIMIT_INTERVAL, interval, MAX_LIMIT_INTERVAL);
+  burst = CLAMP(MIN_LIMIT_BURST, burst, MAX_LIMIT_BURST);
+
+  if (interval >= -TS_FRAC) {
+    /* Find the smallest shift with which the maximum number fits in 16 bits */
+    for (*token_shift = 0; *token_shift < interval + TS_FRAC; (*token_shift)++) {
+      if (burst << (TS_FRAC + interval - *token_shift) < 1U << 16)
+        break;
+    }
+  } else {
+    /* Coarse rate limiting */
+    *token_shift = interval + TS_FRAC;
+    *tokens_per_packet = 1;
+    burst = MAX(1U << -*token_shift, burst);
+  }
+
+  *tokens_per_packet = 1U << (TS_FRAC + interval - *token_shift);
+  *max_tokens = *tokens_per_packet * burst;
+
+  DEBUG_LOG("Tokens max %d packet %d shift %d",
+            *max_tokens, *tokens_per_packet, *token_shift);
 }
 
 /* ================================================== */
@@ -152,21 +306,47 @@ clear_node(Node *node)
 void
 CLG_Initialise(void)
 {
-  clear_subnet(&top_subnet4);
-  clear_subnet(&top_subnet6);
-  if (CNF_GetNoClientLog()) {
-    active = 0;
-  } else {
-    active = 1;
+  int interval, burst, leak_rate;
+
+  max_ntp_tokens = max_cmd_tokens = 0;
+  ntp_tokens_per_packet = cmd_tokens_per_packet = 0;
+  ntp_token_shift = cmd_token_shift = 0;
+  ntp_leak_rate = cmd_leak_rate = 0;
+  ntp_limit_interval = MIN_LIMIT_INTERVAL;
+
+  if (CNF_GetNTPRateLimit(&interval, &burst, &leak_rate)) {
+    set_bucket_params(interval, burst, &max_ntp_tokens, &ntp_tokens_per_packet,
+                      &ntp_token_shift);
+    ntp_leak_rate = CLAMP(MIN_LEAK_RATE, leak_rate, MAX_LEAK_RATE);
+    ntp_limit_interval = CLAMP(MIN_LIMIT_INTERVAL, interval, MAX_LIMIT_INTERVAL);
   }
 
-  nodes = NULL;
-  max_nodes = 0;
-  n_nodes = 0;
+  if (CNF_GetCommandRateLimit(&interval, &burst, &leak_rate)) {
+    set_bucket_params(interval, burst, &max_cmd_tokens, &cmd_tokens_per_packet,
+                      &cmd_token_shift);
+    cmd_leak_rate = CLAMP(MIN_LEAK_RATE, leak_rate, MAX_LEAK_RATE);
+  }
 
-  alloced = 0;
-  alloc_limit = CNF_GetClientLogLimit();
-  alloc_limit_reached = 0;
+  active = !CNF_GetNoClientLog();
+  if (!active) {
+    if (ntp_leak_rate || cmd_leak_rate)
+      LOG_FATAL("ratelimit cannot be used with noclientlog");
+    return;
+  }
+
+  /* Calculate the maximum number of slots that can be allocated in the
+     configured memory limit.  Take into account expanding of the hash
+     table where two copies exist at the same time. */
+  max_slots = CNF_GetClientLogLimit() / (sizeof (Record) * SLOT_SIZE * 3 / 2);
+  max_slots = CLAMP(MIN_SLOTS, max_slots, MAX_SLOTS);
+
+  slots = 0;
+  records = NULL;
+
+  expand_hashtable();
+
+  UTI_GetRandomBytes(&ts_offset, sizeof (ts_offset));
+  ts_offset %= NSEC_PER_SEC / (1U << TS_FRAC);
 }
 
 /* ================================================== */
@@ -174,208 +354,342 @@ CLG_Initialise(void)
 void
 CLG_Finalise(void)
 {
-  int i;
-  
-  for (i = 0; i < n_nodes; i++)
-    Free(nodes[i]);
-  Free(nodes);
-}
-
-/* ================================================== */
-
-static void check_alloc_limit() {
-  if (alloc_limit_reached)
+  if (!active)
     return;
 
-  if (alloced >= alloc_limit) {
-    LOG(LOGS_WARN, LOGF_ClientLog, "Client log memory limit reached");
-    alloc_limit_reached = 1;
+  ARR_DestroyInstance(records);
+}
+
+/* ================================================== */
+
+static uint32_t
+get_ts_from_timespec(struct timespec *ts)
+{
+  uint32_t sec = ts->tv_sec, nsec = ts->tv_nsec;
+
+  nsec += ts_offset;
+  if (nsec >= NSEC_PER_SEC) {
+    nsec -= NSEC_PER_SEC;
+    sec++;
   }
+
+  /* This is fast and accurate enough */
+  return sec << TS_FRAC | (140740U * (nsec >> 15)) >> (32 - TS_FRAC);
 }
 
 /* ================================================== */
 
 static void
-create_subnet(Subnet *parent_subnet, int the_entry)
+update_record(struct timespec *now, uint32_t *last_hit, uint32_t *hits,
+              uint16_t *tokens, uint32_t max_tokens, int token_shift, int8_t *rate)
 {
-  parent_subnet->entry[the_entry] = (void *) MallocNew(Subnet);
-  clear_subnet((Subnet *) parent_subnet->entry[the_entry]);
-  alloced += sizeof (Subnet);
-  check_alloc_limit();
-}
+  uint32_t interval, now_ts, prev_hit, new_tokens;
+  int interval2;
 
-/* ================================================== */
+  now_ts = get_ts_from_timespec(now);
 
-static void
-create_node(Subnet *parent_subnet, int the_entry)
-{
-  Node *new_node;
-  new_node = MallocNew(Node);
-  parent_subnet->entry[the_entry] = (void *) new_node;
-  clear_node(new_node);
+  prev_hit = *last_hit;
+  *last_hit = now_ts;
+  (*hits)++;
 
-  alloced += sizeof (Node);
+  interval = now_ts - prev_hit;
 
-  if (n_nodes == max_nodes) {
-    if (nodes) {
-      assert(max_nodes > 0);
-      max_nodes *= 2;
-      nodes = ReallocArray(Node *, max_nodes, nodes);
-    } else {
-      assert(max_nodes == 0);
-      max_nodes = 16;
-      nodes = MallocArray(Node *, max_nodes);
+  if (prev_hit == INVALID_TS || (int32_t)interval < 0)
+    return;
+
+  if (token_shift >= 0)
+    new_tokens = (now_ts >> token_shift) - (prev_hit >> token_shift);
+  else if (now_ts - prev_hit > max_tokens)
+    new_tokens = max_tokens;
+  else
+    new_tokens = (now_ts - prev_hit) << -token_shift;
+  *tokens = MIN(*tokens + new_tokens, max_tokens);
+
+  /* Convert the interval to scaled and rounded log2 */
+  if (interval) {
+    interval += interval >> 1;
+    for (interval2 = -RATE_SCALE * TS_FRAC; interval2 < -MIN_RATE;
+         interval2 += RATE_SCALE) {
+      if (interval <= 1)
+        break;
+      interval >>= 1;
     }
-    alloced += sizeof (Node *) * (max_nodes - n_nodes);
-  }
-  nodes[n_nodes++] = (Node *) new_node;
-  check_alloc_limit();
-}
-
-/* ================================================== */
-/* Recursively seek out the Node entry for a particular address,
-   expanding subnet tables and node entries as we go if necessary. */
-
-static void *
-find_subnet(Subnet *subnet, uint32_t *addr, int addr_len, int bits_consumed)
-{
-  uint32_t this_subnet;
-
-  this_subnet = get_subnet(addr, bits_consumed);
-  bits_consumed += NBITS;
-
-  if (bits_consumed < 32 * addr_len) {
-    if (!subnet->entry[this_subnet]) {
-      if (alloc_limit_reached)
-        return NULL;
-      create_subnet(subnet, this_subnet);
-    }
-    return find_subnet((Subnet *) subnet->entry[this_subnet], addr, addr_len, bits_consumed);
   } else {
-    if (!subnet->entry[this_subnet]) {
-      if (alloc_limit_reached)
-        return NULL;
-      create_node(subnet, this_subnet);
-    }
-    return subnet->entry[this_subnet];
+    interval2 = -RATE_SCALE * (TS_FRAC + 1);
   }
-}
 
-/* ================================================== */
-
-static Node *
-get_node(IPAddr *ip)
-{
-  uint32_t ip6[4];
-
-  switch (ip->family) {
-    case IPADDR_INET4:
-      return (Node *)find_subnet(&top_subnet4, &ip->addr.in4, 1, 0);
-    case IPADDR_INET6:
-      split_ip6(ip, ip6);
-      return (Node *)find_subnet(&top_subnet6, ip6, 4, 0);
-    default:
-      return NULL;
-  }
-}
-
-/* ================================================== */
-
-void
-CLG_LogNTPClientAccess (IPAddr *client, time_t now)
-{
-  Node *node;
-
-  if (active) {
-    node = get_node(client);
-    if (node == NULL)
-      return;
-
-    node->ip_addr = *client;
-    ++node->client_hits;
-    node->last_ntp_hit = now;
-  }
-}
-
-/* ================================================== */
-
-void
-CLG_LogNTPPeerAccess(IPAddr *client, time_t now)
-{
-  Node *node;
-
-  if (active) {
-    node = get_node(client);
-    if (node == NULL)
-      return;
-
-    node->ip_addr = *client;
-    ++node->peer_hits;
-    node->last_ntp_hit = now;
-  }
-}
-
-/* ================================================== */
-
-void
-CLG_LogCommandAccess(IPAddr *client, CLG_Command_Type type, time_t now)
-{
-  Node *node;
-
-  if (active) {
-    node = get_node(client);
-    if (node == NULL)
-      return;
-
-    node->ip_addr = *client;
-    node->last_cmd_hit = now;
-    switch (type) {
-      case CLG_CMD_AUTH:
-        ++node->cmd_hits_auth;
-        break;
-      case CLG_CMD_NORMAL:
-        ++node->cmd_hits_normal;
-        break;
-      case CLG_CMD_BAD_PKT:
-        ++node->cmd_hits_bad;
-        break;
-      default:
-        assert(0);
-        break;
-    }
-  }
-}
-
-/* ================================================== */
-
-CLG_Status
-CLG_GetClientAccessReportByIndex(int index, RPT_ClientAccessByIndex_Report *report,
-                                 time_t now, unsigned long *n_indices)
-{
-  Node *node;
-
-  *n_indices = n_nodes;
-
-  if (!active) {
-    return CLG_INACTIVE;
+  /* Update the rate in a rough approximation of exponential moving average */
+  if (*rate == INVALID_RATE) {
+    *rate = -interval2;
   } else {
-
-    if ((index < 0) || (index >= n_nodes)) {
-      return CLG_INDEXTOOLARGE;
+    if (*rate < -interval2) {
+      (*rate)++;
+    } else if (*rate > -interval2) {
+      if (*rate > RATE_SCALE * 5 / 2 - interval2)
+        *rate = RATE_SCALE * 5 / 2 - interval2;
+      else
+        *rate = (*rate - interval2 - 1) / 2;
     }
-    
-    node = nodes[index];
-    
-    report->ip_addr = node->ip_addr;
-    report->client_hits = node->client_hits;
-    report->peer_hits = node->peer_hits;
-    report->cmd_hits_auth = node->cmd_hits_auth;
-    report->cmd_hits_normal = node->cmd_hits_normal;
-    report->cmd_hits_bad = node->cmd_hits_bad;
-    report->last_ntp_hit_ago = now - node->last_ntp_hit;
-    report->last_cmd_hit_ago = now - node->last_cmd_hit;
-    
-    return CLG_SUCCESS;
+  }
+}
+
+/* ================================================== */
+
+static int
+get_index(Record *record)
+{
+  return record - (Record *)ARR_GetElements(records);
+}
+
+/* ================================================== */
+
+int
+CLG_GetClientIndex(IPAddr *client)
+{
+  Record *record;
+
+  record = get_record(client);
+  if (record == NULL)
+    return -1;
+
+  return get_index(record);
+}
+
+/* ================================================== */
+
+int
+CLG_LogNTPAccess(IPAddr *client, struct timespec *now)
+{
+  Record *record;
+
+  total_ntp_hits++;
+
+  record = get_record(client);
+  if (record == NULL)
+    return -1;
+
+  /* Update one of the two rates depending on whether the previous request
+     of the client had a reply or it timed out */
+  update_record(now, &record->last_ntp_hit, &record->ntp_hits,
+                &record->ntp_tokens, max_ntp_tokens, ntp_token_shift,
+                record->flags & FLAG_NTP_DROPPED ?
+                &record->ntp_timeout_rate : &record->ntp_rate);
+
+  DEBUG_LOG("NTP hits %"PRIu32" rate %d trate %d tokens %d",
+            record->ntp_hits, record->ntp_rate, record->ntp_timeout_rate,
+            record->ntp_tokens);
+
+  return get_index(record);
+}
+
+/* ================================================== */
+
+int
+CLG_LogCommandAccess(IPAddr *client, struct timespec *now)
+{
+  Record *record;
+
+  total_cmd_hits++;
+
+  record = get_record(client);
+  if (record == NULL)
+    return -1;
+
+  update_record(now, &record->last_cmd_hit, &record->cmd_hits,
+                &record->cmd_tokens, max_cmd_tokens, cmd_token_shift,
+                &record->cmd_rate);
+
+  DEBUG_LOG("Cmd hits %"PRIu32" rate %d tokens %d",
+            record->cmd_hits, record->cmd_rate, record->cmd_tokens);
+
+  return get_index(record);
+}
+
+/* ================================================== */
+
+static int
+limit_response_random(int leak_rate)
+{
+  static uint32_t rnd;
+  static int bits_left = 0;
+  int r;
+
+  if (bits_left < leak_rate) {
+    UTI_GetRandomBytes(&rnd, sizeof (rnd));
+    bits_left = 8 * sizeof (rnd);
   }
 
+  /* Return zero on average once per 2^leak_rate */
+  r = rnd % (1U << leak_rate) ? 1 : 0;
+  rnd >>= leak_rate;
+  bits_left -= leak_rate;
+
+  return r;
+}
+
+/* ================================================== */
+
+int
+CLG_LimitNTPResponseRate(int index)
+{
+  Record *record;
+  int drop;
+
+  if (!ntp_tokens_per_packet)
+    return 0;
+
+  record = ARR_GetElement(records, index);
+  record->flags &= ~FLAG_NTP_DROPPED;
+
+  if (record->ntp_tokens >= ntp_tokens_per_packet) {
+    record->ntp_tokens -= ntp_tokens_per_packet;
+    return 0;
+  }
+
+  drop = limit_response_random(ntp_leak_rate);
+
+  /* Poorly implemented clients may send new requests at even a higher rate
+     when they are not getting replies.  If the request rate seems to be more
+     than twice as much as when replies are sent, give up on rate limiting to
+     reduce the amount of traffic.  Invert the sense of the leak to respond to
+     most of the requests, but still keep the estimated rate updated. */
+  if (record->ntp_timeout_rate != INVALID_RATE &&
+      record->ntp_timeout_rate > record->ntp_rate + RATE_SCALE)
+    drop = !drop;
+
+  if (!drop) {
+    record->ntp_tokens = 0;
+    return 0;
+  }
+
+  record->flags |= FLAG_NTP_DROPPED;
+  record->ntp_drops++;
+  total_ntp_drops++;
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+CLG_LimitCommandResponseRate(int index)
+{
+  Record *record;
+
+  if (!cmd_tokens_per_packet)
+    return 0;
+
+  record = ARR_GetElement(records, index);
+
+  if (record->cmd_tokens >= cmd_tokens_per_packet) {
+    record->cmd_tokens -= cmd_tokens_per_packet;
+    return 0;
+  }
+
+  if (!limit_response_random(cmd_leak_rate)) {
+    record->cmd_tokens = 0;
+    return 0;
+  }
+
+  record->cmd_drops++;
+  total_cmd_drops++;
+
+  return 1;
+}
+
+/* ================================================== */
+
+void CLG_GetNtpTimestamps(int index, NTP_int64 **rx_ts, NTP_int64 **tx_ts)
+{
+  Record *record;
+
+  record = ARR_GetElement(records, index);
+
+  *rx_ts = &record->ntp_rx_ts;
+  *tx_ts = &record->ntp_tx_ts;
+}
+
+/* ================================================== */
+
+int
+CLG_GetNtpMinPoll(void)
+{
+  return ntp_limit_interval;
+}
+
+/* ================================================== */
+
+int
+CLG_GetNumberOfIndices(void)
+{
+  if (!active)
+    return -1;
+
+  return ARR_GetSize(records);
+}
+
+/* ================================================== */
+
+static int get_interval(int rate)
+{
+  if (rate == INVALID_RATE)
+    return 127;
+
+  rate += rate > 0 ? RATE_SCALE / 2 : -RATE_SCALE / 2;
+
+  return rate / -RATE_SCALE;
+}
+
+/* ================================================== */
+
+static uint32_t get_last_ago(uint32_t x, uint32_t y)
+{
+  if (y == INVALID_TS || (int32_t)(x - y) < 0)
+    return -1;
+
+  return (x - y) >> TS_FRAC;
+}
+
+/* ================================================== */
+
+int
+CLG_GetClientAccessReportByIndex(int index, RPT_ClientAccessByIndex_Report *report, struct timespec *now)
+{
+  Record *record;
+  uint32_t now_ts;
+
+  if (!active || index < 0 || index >= ARR_GetSize(records))
+    return 0;
+
+  record = ARR_GetElement(records, index);
+
+  if (record->ip_addr.family == IPADDR_UNSPEC)
+    return 0;
+
+  now_ts = get_ts_from_timespec(now);
+
+  report->ip_addr = record->ip_addr;
+  report->ntp_hits = record->ntp_hits;
+  report->cmd_hits = record->cmd_hits;
+  report->ntp_drops = record->ntp_drops;
+  report->cmd_drops = record->cmd_drops;
+  report->ntp_interval = get_interval(record->ntp_rate);
+  report->cmd_interval = get_interval(record->cmd_rate);
+  report->ntp_timeout_interval = get_interval(record->ntp_timeout_rate);
+  report->last_ntp_hit_ago = get_last_ago(now_ts, record->last_ntp_hit);
+  report->last_cmd_hit_ago = get_last_ago(now_ts, record->last_cmd_hit);
+
+  return 1;
+}
+
+/* ================================================== */
+
+void
+CLG_GetServerStatsReport(RPT_ServerStatsReport *report)
+{
+  report->ntp_hits = total_ntp_hits;
+  report->cmd_hits = total_cmd_hits;
+  report->ntp_drops = total_ntp_drops;
+  report->cmd_drops = total_cmd_drops;
+  report->log_drops = total_record_drops;
 }

clientlog.h

@@ -33,32 +33,18 @@
 
 extern void CLG_Initialise(void);
 extern void CLG_Finalise(void);
-extern void CLG_LogNTPClientAccess(IPAddr *client, time_t now);
-extern void CLG_LogNTPPeerAccess(IPAddr *client, time_t now);
-
-/* When logging command packets, there are several subtypes */
-
-typedef enum {
-  CLG_CMD_AUTH,                 /* authenticated */
-  CLG_CMD_NORMAL,               /* normal */
-  CLG_CMD_BAD_PKT               /* bad version or packet length */
-} CLG_Command_Type;
-
-extern void CLG_LogCommandAccess(IPAddr *client, CLG_Command_Type type, time_t now);
+extern int CLG_GetClientIndex(IPAddr *client);
+extern int CLG_LogNTPAccess(IPAddr *client, struct timespec *now);
+extern int CLG_LogCommandAccess(IPAddr *client, struct timespec *now);
+extern int CLG_LimitNTPResponseRate(int index);
+extern int CLG_LimitCommandResponseRate(int index);
+extern void CLG_GetNtpTimestamps(int index, NTP_int64 **rx_ts, NTP_int64 **tx_ts);
+extern int CLG_GetNtpMinPoll(void);
 
 /* And some reporting functions, for use by chronyc. */
-/* TBD */
 
-typedef enum {
-  CLG_SUCCESS,                  /* All is well */
-  CLG_EMPTYSUBNET,              /* No hosts logged in requested subnet */
-  CLG_BADSUBNET,                /* Subnet requested is not 0, 8, 16 or 24 bits */
-  CLG_INACTIVE,                 /* Facility not active */
-  CLG_INDEXTOOLARGE             /* Node index is higher than number of nodes present */
-} CLG_Status;
-
-CLG_Status
-CLG_GetClientAccessReportByIndex(int index, RPT_ClientAccessByIndex_Report *report,
-                                 time_t now, unsigned long *n_indices);
+extern int CLG_GetNumberOfIndices(void);
+extern int CLG_GetClientAccessReportByIndex(int index, RPT_ClientAccessByIndex_Report *report, struct timespec *now);
+extern void CLG_GetServerStatsReport(RPT_ServerStatsReport *report);
 
 #endif /* GOT_CLIENTLOG_H */

cmac.h

@@ -0,0 +1,41 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2019
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for CMAC.
+
+  */
+
+#ifndef GOT_CMAC_H
+#define GOT_CMAC_H
+
+typedef struct CMC_Instance_Record *CMC_Instance;
+
+extern unsigned int CMC_GetKeyLength(const char *cipher);
+extern CMC_Instance CMC_CreateInstance(const char *cipher, const unsigned char *key,
+                                       unsigned int length);
+extern unsigned int CMC_Hash(CMC_Instance inst, const unsigned char *in, unsigned int in_len,
+                             unsigned char *out, unsigned int out_len);
+extern void CMC_DestroyInstance(CMC_Instance inst);
+
+#endif
+

cmac_nettle.c

@@ -0,0 +1,115 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2019
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Support for AES128 and AES256 CMAC in Nettle.
+
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include <nettle/cmac.h>
+
+#include "cmac.h"
+#include "memory.h"
+
+struct CMC_Instance_Record {
+  int key_length;
+  union {
+    struct cmac_aes128_ctx aes128;
+    struct cmac_aes256_ctx aes256;
+  } context;
+};
+
+/* ================================================== */
+
+unsigned int
+CMC_GetKeyLength(const char *cipher)
+{
+  if (strcmp(cipher, "AES128") == 0)
+    return AES128_KEY_SIZE;
+  else if (strcmp(cipher, "AES256") == 0)
+    return AES256_KEY_SIZE;
+  return 0;
+}
+
+/* ================================================== */
+
+CMC_Instance
+CMC_CreateInstance(const char *cipher, const unsigned char *key, unsigned int length)
+{
+  CMC_Instance inst;
+
+  if (length == 0 || length != CMC_GetKeyLength(cipher))
+    return NULL;
+
+  inst = MallocNew(struct CMC_Instance_Record);
+  inst->key_length = length;
+
+  switch (length) {
+    case AES128_KEY_SIZE:
+      cmac_aes128_set_key(&inst->context.aes128, key);
+      break;
+    case AES256_KEY_SIZE:
+      cmac_aes256_set_key(&inst->context.aes256, key);
+      break;
+    default:
+      assert(0);
+  }
+
+  return inst;
+}
+
+/* ================================================== */
+
+unsigned int
+CMC_Hash(CMC_Instance inst, const unsigned char *in, unsigned int in_len,
+         unsigned char *out, unsigned int out_len)
+{
+  if (out_len > CMAC128_DIGEST_SIZE)
+    out_len = CMAC128_DIGEST_SIZE;
+
+  switch (inst->key_length) {
+    case AES128_KEY_SIZE:
+      cmac_aes128_update(&inst->context.aes128, in_len, in);
+      cmac_aes128_digest(&inst->context.aes128, out_len, out);
+      break;
+    case AES256_KEY_SIZE:
+      cmac_aes256_update(&inst->context.aes256, in_len, in);
+      cmac_aes256_digest(&inst->context.aes256, out_len, out);
+      break;
+    default:
+      assert(0);
+  }
+
+  return out_len;
+}
+
+/* ================================================== */
+
+void
+CMC_DestroyInstance(CMC_Instance inst)
+{
+  Free(inst);
+}

cmdparse.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2013-2014
+ * Copyright (C) Miroslav Lichvar  2013-2014, 2016
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -39,246 +39,173 @@
 
 /* ================================================== */
 
-CPS_Status
+int
 CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src)
 {
   char *hostname, *cmd;
-  int n, done;
-  CPS_Status result;
+  int n;
   
   src->port = SRC_DEFAULT_PORT;
   src->params.minpoll = SRC_DEFAULT_MINPOLL;
   src->params.maxpoll = SRC_DEFAULT_MAXPOLL;
+  src->params.connectivity = SRC_ONLINE;
+  src->params.auto_offline = 0;
   src->params.presend_minpoll = SRC_DEFAULT_PRESEND_MINPOLL;
+  src->params.burst = 0;
+  src->params.iburst = 0;
+  src->params.min_stratum = SRC_DEFAULT_MINSTRATUM;
+  src->params.poll_target = SRC_DEFAULT_POLLTARGET;
+  src->params.version = 0;
+  src->params.max_sources = SRC_DEFAULT_MAXSOURCES;
+  src->params.min_samples = SRC_DEFAULT_MINSAMPLES;
+  src->params.max_samples = SRC_DEFAULT_MAXSAMPLES;
+  src->params.filter_length = 0;
+  src->params.interleaved = 0;
+  src->params.sel_options = 0;
+  src->params.nts = 0;
+  src->params.nts_port = SRC_DEFAULT_NTSPORT;
   src->params.authkey = INACTIVE_AUTHKEY;
   src->params.max_delay = SRC_DEFAULT_MAXDELAY;
   src->params.max_delay_ratio = SRC_DEFAULT_MAXDELAYRATIO;
   src->params.max_delay_dev_ratio = SRC_DEFAULT_MAXDELAYDEVRATIO;
-  src->params.online = 1;
-  src->params.auto_offline = 0;
-  src->params.iburst = 0;
-  src->params.min_stratum = SRC_DEFAULT_MINSTRATUM;
-  src->params.poll_target = SRC_DEFAULT_POLLTARGET;
-  src->params.version = NTP_VERSION;
-  src->params.max_sources = SRC_DEFAULT_MAXSOURCES;
-  src->params.min_samples = SRC_DEFAULT_MINSAMPLES;
-  src->params.max_samples = SRC_DEFAULT_MAXSAMPLES;
-  src->params.sel_option = SRC_SelectNormal;
+  src->params.min_delay = 0.0;
+  src->params.asymmetry = SRC_DEFAULT_ASYMMETRY;
+  src->params.offset = 0.0;
 
-  result = CPS_Success;
-  
   hostname = line;
   line = CPS_SplitWord(line);
 
-  if (!*hostname) {
-    result = CPS_BadHost;
-  } else {
-    src->name = hostname;
+  if (!*hostname)
+    return 0;
 
-    /* Parse subfields */
-    done = 0;
-    do {
-      cmd = line;
-      line = CPS_SplitWord(line);
+  src->name = hostname;
 
-      if (*cmd) {
-        if (!strcasecmp(cmd, "port")) {
-          if (sscanf(line, "%hu%n", &src->port, &n) != 1) {
-            result = CPS_BadPort;
-            done = 1;
-          } else {
-            line += n;
-          }
-        } else if (!strcasecmp(cmd, "minpoll")) {
-          if (sscanf(line, "%d%n", &src->params.minpoll, &n) != 1) {
-            result = CPS_BadMinpoll;
-            done = 1;
-          } else {
-            line += n;
-          }
-        } else if (!strcasecmp(cmd, "maxpoll")) {
-          if (sscanf(line, "%d%n", &src->params.maxpoll, &n) != 1) {
-            result = CPS_BadMaxpoll;
-            done = 1;
-          } else {
-            line += n;
-          }
-        } else if (!strcasecmp(cmd, "presend")) {
-          if (sscanf(line, "%d%n", &src->params.presend_minpoll, &n) != 1) {
-            result = CPS_BadPresend;
-            done = 1;
-          } else {
-            line += n;
-          }
-        } else if (!strcasecmp(cmd, "maxdelaydevratio")) {
-          if (sscanf(line, "%lf%n", &src->params.max_delay_dev_ratio, &n) != 1) {
-            result = CPS_BadMaxdelaydevratio;
-            done = 1;
-          } else {
-            line += n;
-          }
-        } else if (!strcasecmp(cmd, "maxdelayratio")) {
-          if (sscanf(line, "%lf%n", &src->params.max_delay_ratio, &n) != 1) {
-            result = CPS_BadMaxdelayratio;
-            done = 1;
-          } else {
-            line += n;
-          }
-        } else if (!strcasecmp(cmd, "maxdelay")) {
-          if (sscanf(line, "%lf%n", &src->params.max_delay, &n) != 1) {
-            result = CPS_BadMaxdelay;
-            done = 1;
-          } else {
-            line += n;
-          }
-        } else if (!strcasecmp(cmd, "key")) {
-          if (sscanf(line, "%"SCNu32"%n", &src->params.authkey, &n) != 1 ||
-              src->params.authkey == INACTIVE_AUTHKEY) {
-            result = CPS_BadKey;
-            done = 1;
-          } else {
-            line += n;
-          }
-        } else if (!strcasecmp(cmd, "offline")) {
-          src->params.online = 0;
+  /* Parse options */
+  for (; *line; line += n) {
+    cmd = line;
+    line = CPS_SplitWord(line);
+    n = 0;
 
-        } else if (!strcasecmp(cmd, "auto_offline")) {
-          src->params.auto_offline = 1;
-        
-        } else if (!strcasecmp(cmd, "iburst")) {
-          src->params.iburst = 1;
-
-        } else if (!strcasecmp(cmd, "minstratum")) {
-          if (sscanf(line, "%d%n", &src->params.min_stratum, &n) != 1) {
-            result = CPS_BadMinstratum;
-            done = 1;
-          } else {
-            line += n;
-          }
-
-        } else if (!strcasecmp(cmd, "polltarget")) {
-          if (sscanf(line, "%d%n", &src->params.poll_target, &n) != 1) {
-            result = CPS_BadPolltarget;
-            done = 1;
-          } else {
-            line += n;
-          }
-
-        } else if (!strcasecmp(cmd, "noselect")) {
-          src->params.sel_option = SRC_SelectNoselect;
-        
-        } else if (!strcasecmp(cmd, "prefer")) {
-          src->params.sel_option = SRC_SelectPrefer;
-        
-        } else if (!strcasecmp(cmd, "version")) {
-          if (sscanf(line, "%d%n", &src->params.version, &n) != 1) {
-            result = CPS_BadVersion;
-            done = 1;
-          } else {
-            line += n;
-          }
-
-        } else if (!strcasecmp(cmd, "maxsources")) {
-          if (sscanf(line, "%d%n", &src->params.max_sources, &n) != 1) {
-            result = CPS_BadMaxsources;
-            done = 1;
-          } else {
-            line += n;
-          }
-
-        } else if (!strcasecmp(cmd, "minsamples")) {
-          if (sscanf(line, "%d%n", &src->params.min_samples, &n) != 1) {
-            result = CPS_BadMinsamples;
-            done = 1;
-          } else {
-            line += n;
-          }
-
-        } else if (!strcasecmp(cmd, "maxsamples")) {
-          if (sscanf(line, "%d%n", &src->params.max_samples, &n) != 1) {
-            result = CPS_BadMaxsamples;
-            done = 1;
-          } else {
-            line += n;
-          }
-
-        } else {
-          result = CPS_BadOption;
-          done = 1;
-        }
-      } else {
-        done = 1;
-      }
-    } while (!done);
+    if (!strcasecmp(cmd, "auto_offline")) {
+      src->params.auto_offline = 1;
+    } else if (!strcasecmp(cmd, "burst")) {
+      src->params.burst = 1;
+    } else if (!strcasecmp(cmd, "iburst")) {
+      src->params.iburst = 1;
+    } else if (!strcasecmp(cmd, "offline")) {
+      src->params.connectivity = SRC_OFFLINE;
+    } else if (!strcasecmp(cmd, "noselect")) {
+      src->params.sel_options |= SRC_SELECT_NOSELECT;
+    } else if (!strcasecmp(cmd, "prefer")) {
+      src->params.sel_options |= SRC_SELECT_PREFER;
+    } else if (!strcasecmp(cmd, "require")) {
+      src->params.sel_options |= SRC_SELECT_REQUIRE;
+    } else if (!strcasecmp(cmd, "trust")) {
+      src->params.sel_options |= SRC_SELECT_TRUST;
+    } else if (!strcasecmp(cmd, "key")) {
+      if (sscanf(line, "%"SCNu32"%n", &src->params.authkey, &n) != 1 ||
+          src->params.authkey == INACTIVE_AUTHKEY)
+        return 0;
+    } else if (!strcasecmp(cmd, "asymmetry")) {
+      if (sscanf(line, "%lf%n", &src->params.asymmetry, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "filter")) {
+      if (sscanf(line, "%d%n", &src->params.filter_length, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "maxdelay")) {
+      if (sscanf(line, "%lf%n", &src->params.max_delay, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "maxdelayratio")) {
+      if (sscanf(line, "%lf%n", &src->params.max_delay_ratio, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "maxdelaydevratio")) {
+      if (sscanf(line, "%lf%n", &src->params.max_delay_dev_ratio, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "maxpoll")) {
+      if (sscanf(line, "%d%n", &src->params.maxpoll, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "maxsamples")) {
+      if (sscanf(line, "%d%n", &src->params.max_samples, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "maxsources")) {
+      if (sscanf(line, "%d%n", &src->params.max_sources, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "mindelay")) {
+      if (sscanf(line, "%lf%n", &src->params.min_delay, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "minpoll")) {
+      if (sscanf(line, "%d%n", &src->params.minpoll, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "minsamples")) {
+      if (sscanf(line, "%d%n", &src->params.min_samples, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "minstratum")) {
+      if (sscanf(line, "%d%n", &src->params.min_stratum, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "nts")) {
+      src->params.nts = 1;
+    } else if (!strcasecmp(cmd, "ntsport")) {
+      if (sscanf(line, "%d%n", &src->params.nts_port, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "offset")) {
+      if (sscanf(line, "%lf%n", &src->params.offset, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "port")) {
+      if (sscanf(line, "%hu%n", &src->port, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "polltarget")) {
+      if (sscanf(line, "%d%n", &src->params.poll_target, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "presend")) {
+      if (sscanf(line, "%d%n", &src->params.presend_minpoll, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "version")) {
+      if (sscanf(line, "%d%n", &src->params.version, &n) != 1)
+        return 0;
+    } else if (!strcasecmp(cmd, "xleave")) {
+      src->params.interleaved = 1;
+    } else {
+      return 0;
+    }
   }
 
-  return result;
+  return 1;
 }
 
 /* ================================================== */
 
-void
-CPS_StatusToString(CPS_Status status, char *dest, int len)
+int
+CPS_ParseLocal(char *line, int *stratum, int *orphan, double *distance)
 {
-  const char *s = NULL;
+  int n;
+  char *cmd;
 
-  if (len > 0)
-    dest[0] = '\0';
+  *stratum = 10;
+  *distance = 1.0;
+  *orphan = 0;
 
-  switch (status) {
-    case CPS_Success:
-      return;
-    case CPS_BadOption:
-      s = "server/peer/pool option";
-      break;
-    case CPS_BadHost:
-      s = "address";
-      break;
-    case CPS_BadPort:
-      s = "port";
-      break;
-    case CPS_BadMinpoll:
-      s = "minpoll";
-      break;
-    case CPS_BadMaxpoll:
-      s = "maxpoll";
-      break;
-    case CPS_BadPresend:
-      s = "presend";
-      break;
-    case CPS_BadMaxdelaydevratio:
-      s = "maxdelaydevratio";
-      break;
-    case CPS_BadMaxdelayratio:
-      s = "maxdelayratio";
-      break;
-    case CPS_BadMaxdelay:
-      s = "maxdelay";
-      break;
-    case CPS_BadKey:
-      s = "key";
-      break;
-    case CPS_BadMinstratum:
-      s = "minstratum";
-      break;
-    case CPS_BadPolltarget:
-      s = "polltarget";
-      break;
-    case CPS_BadVersion:
-      s = "version";
-      break;
-    case CPS_BadMaxsources:
-      s = "maxsources";
-      break;
-    case CPS_BadMinsamples:
-      s = "minsamples";
-      break;
-    case CPS_BadMaxsamples:
-      s = "maxsamples";
-      break;
+  while (*line) {
+    cmd = line;
+    line = CPS_SplitWord(line);
+
+    if (!strcasecmp(cmd, "stratum")) {
+      if (sscanf(line, "%d%n", stratum, &n) != 1 ||
+          *stratum >= NTP_MAX_STRATUM || *stratum <= 0)
+        return 0;
+    } else if (!strcasecmp(cmd, "orphan")) {
+      *orphan = 1;
+      n = 0;
+    } else if (!strcasecmp(cmd, "distance")) {
+      if (sscanf(line, "%lf%n", distance, &n) != 1)
+        return 0;
+    } else {
+      return 0;
+    }
+
+    line += n;
   }
 
-  snprintf(dest, len, "Invalid %s", s);
+  return 1;
 }
 
 /* ================================================== */
@@ -341,7 +268,7 @@ CPS_SplitWord(char *line)
 /* ================================================== */
 
 int
-CPS_ParseKey(char *line, uint32_t *id, const char **hash, char **key)
+CPS_ParseKey(char *line, uint32_t *id, const char **type, char **key)
 {
   char *s1, *s2, *s3, *s4;
 
@@ -358,10 +285,10 @@ CPS_ParseKey(char *line, uint32_t *id, const char **hash, char **key)
     return 0;
 
   if (*s3) {
-    *hash = s2;
+    *type = s2;
     *key = s3;
   } else {
-    *hash = "MD5";
+    *type = "MD5";
     *key = s2;
   }
 

cmdparse.h

@@ -30,26 +30,6 @@
 #include "srcparams.h"
 #include "addressing.h"
 
-typedef enum {
-  CPS_Success,
-  CPS_BadOption,
-  CPS_BadHost,
-  CPS_BadPort,
-  CPS_BadMinpoll,
-  CPS_BadMaxpoll,
-  CPS_BadPresend,
-  CPS_BadMaxdelaydevratio,
-  CPS_BadMaxdelayratio,
-  CPS_BadMaxdelay,
-  CPS_BadKey,
-  CPS_BadMinstratum,
-  CPS_BadPolltarget,
-  CPS_BadVersion,
-  CPS_BadMaxsources,
-  CPS_BadMinsamples,
-  CPS_BadMaxsamples,
-} CPS_Status;
-
 typedef struct {
   char *name;
   unsigned short port;
@@ -57,10 +37,10 @@ typedef struct {
 } CPS_NTP_Source;
 
 /* Parse a command to add an NTP server or peer */
-extern CPS_Status CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src);
+extern int CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src);
   
-/* Get a string describing error status */
-extern void CPS_StatusToString(CPS_Status status, char *dest, int len);
+/* Parse a command to enable local reference */
+extern int CPS_ParseLocal(char *line, int *stratum, int *orphan, double *distance);
 
 /* Remove extra white-space and comments */
 extern void CPS_NormalizeLine(char *line);
@@ -69,6 +49,6 @@ extern void CPS_NormalizeLine(char *line);
 extern char *CPS_SplitWord(char *line);
 
 /* Parse a key from keyfile */
-extern int CPS_ParseKey(char *line, uint32_t *id, const char **hash, char **key);
+extern int CPS_ParseKey(char *line, uint32_t *id, const char **type, char **key);
 
 #endif /* GOT_CMDPARSE_H */

conf.h

@@ -31,7 +31,7 @@
 #include "addressing.h"
 #include "reference.h"
 
-extern void CNF_Initialise(int restarted);
+extern void CNF_Initialise(int restarted, int client_only);
 extern void CNF_Finalise(void);
 
 extern char *CNF_GetRtcDevice(void);
@@ -52,7 +52,7 @@ extern char *CNF_GetDriftFile(void);
 extern char *CNF_GetLogDir(void);
 extern char *CNF_GetDumpDir(void);
 extern int CNF_GetLogBanner(void);
-extern int CNF_GetLogMeasurements(void);
+extern int CNF_GetLogMeasurements(int *raw);
 extern int CNF_GetLogStatistics(void);
 extern int CNF_GetLogTracking(void);
 extern int CNF_GetLogRtc(void);
@@ -60,14 +60,13 @@ extern int CNF_GetLogRefclocks(void);
 extern int CNF_GetLogTempComp(void);
 extern char *CNF_GetKeysFile(void);
 extern char *CNF_GetRtcFile(void);
-extern int CNF_GetDumpOnExit(void);
 extern int CNF_GetManualEnabled(void);
 extern int CNF_GetCommandPort(void);
 extern int CNF_GetRtcOnUtc(void);
 extern int CNF_GetRtcSync(void);
 extern void CNF_GetMakeStep(int *limit, double *threshold);
 extern void CNF_GetMaxChange(int *delay, int *ignore, double *offset);
-extern void CNF_GetLogChange(int *enabled, double *threshold);
+extern double CNF_GetLogChange(void);
 extern void CNF_GetMailOnChange(int *enabled, double *threshold, char **user);
 extern int CNF_GetNoClientLog(void);
 extern unsigned long CNF_GetClientLogLimit(void);
@@ -76,6 +75,7 @@ extern void CNF_GetBindAddress(int family, IPAddr *addr);
 extern void CNF_GetBindAcquisitionAddress(int family, IPAddr *addr);
 extern void CNF_GetBindCommandAddress(int family, IPAddr *addr);
 extern char *CNF_GetBindCommandPath(void);
+extern char *CNF_GetNtpSigndSocket(void);
 extern char *CNF_GetPidFile(void);
 extern REF_LeapMode CNF_GetLeapSecMode(void);
 extern char *CNF_GetLeapSecTimezone(void);
@@ -83,21 +83,25 @@ extern char *CNF_GetLeapSecTimezone(void);
 /* Value returned in ppm, as read from file */
 extern double CNF_GetMaxUpdateSkew(void);
 extern double CNF_GetMaxClockError(void);
+extern double CNF_GetMaxDrift(void);
 extern double CNF_GetCorrectionTimeRatio(void);
 extern double CNF_GetMaxSlewRate(void);
 
 extern double CNF_GetMaxDistance(void);
+extern double CNF_GetMaxJitter(void);
 extern double CNF_GetReselectDistance(void);
 extern double CNF_GetStratumWeight(void);
 extern double CNF_GetCombineLimit(void);
 
-extern int CNF_AllowLocalReference(int *stratum);
+extern int CNF_AllowLocalReference(int *stratum, int *orphan, double *distance);
 
 extern void CNF_SetupAccessRestrictions(void);
 
 extern int CNF_GetSchedPriority(void);
 extern int CNF_GetLockMemory(void);
 
+extern int CNF_GetNTPRateLimit(int *interval, int *burst, int *leak);
+extern int CNF_GetCommandRateLimit(int *interval, int *burst, int *leak);
 extern void CNF_GetSmooth(double *max_freq, double *max_wander, int *leap_only);
 extern void CNF_GetTempComp(char **file, double *interval, char **point_file, double *T0, double *k0, double *k1, double *k2);
 
@@ -114,4 +118,38 @@ extern char *CNF_GetHwclockFile(void);
 extern int CNF_GetInitSources(void);
 extern double CNF_GetInitStepThreshold(void);
 
+typedef enum {
+  CNF_HWTS_RXFILTER_ANY,
+  CNF_HWTS_RXFILTER_NONE,
+  CNF_HWTS_RXFILTER_NTP,
+  CNF_HWTS_RXFILTER_ALL,
+} CNF_HwTs_RxFilter;
+
+typedef struct {
+  char *name;
+  int minpoll;
+  int min_samples;
+  int max_samples;
+  int nocrossts;
+  CNF_HwTs_RxFilter rxfilter;
+  double precision;
+  double tx_comp;
+  double rx_comp;
+} CNF_HwTsInterface;
+
+extern int CNF_GetHwTsInterface(unsigned int index, CNF_HwTsInterface **iface);
+
+extern char *CNF_GetNtsDumpDir(void);
+extern char *CNF_GetNtsNtpServer(void);
+extern char *CNF_GetNtsServerCertFile(void);
+extern char *CNF_GetNtsServerKeyFile(void);
+extern int CNF_GetNtsServerPort(void);
+extern int CNF_GetNtsServerProcesses(void);
+extern int CNF_GetNtsServerConnections(void);
+extern int CNF_GetNtsRefresh(void);
+extern int CNF_GetNtsRotate(void);
+extern char *CNF_GetNtsTrustedCertFile(void);
+extern int CNF_GetNoSystemCert(void);
+extern int CNF_GetNoCertTimeCheck(void);
+
 #endif /* GOT_CONF_H */

configure

@@ -4,7 +4,9 @@
 # chronyd/chronyc - Programs for keeping computer clocks accurate.
 #
 # Copyright (C) Richard P. Curnow  1997-2003
-# Copyright (C) Miroslav Lichvar  2009, 2012-2015
+# Copyright (C) Bryan Christianson  2016
+# Copyright (C) Miroslav Lichvar  2009, 2012-2018
+# Copyright (C) Stefan R. Filipek  2019
 #
 # =======================================================================
 
@@ -24,6 +26,7 @@ test_code () {
   printf "%s" "Checking for $name : "
 
   (
+    echo "#include \"config.h\""
     for h in $headers; do
       echo "#include <$h>"
     done
@@ -52,6 +55,34 @@ test_code () {
   return $result
 }
 #}}}
+#{{{ test_executable
+test_executable () {
+  name=$1
+  executable=$2
+  options=$3
+
+  printf "%s" "Checking for $name : "
+
+  echo $executable $options >> config.log
+  $executable $options >> config.log 2>&1
+
+  if [ $? -eq 0 ]
+  then
+    echo "Yes"
+    result=0
+  else
+    echo "No"
+    result=1
+  fi
+  echo >> config.log
+  return $result
+}
+#}}}
+#{{{ pkg_config
+pkg_config () {
+  $PKG_CONFIG "$@" 2>> config.log
+}
+#}}}
 #{{{ usage
 usage () {
   cat <<EOF
@@ -79,13 +110,15 @@ For better control, use the options below.
   --disable-readline     Disable line editing support
   --without-readline     Don't use GNU readline even if it is available
   --without-editline     Don't use editline even if it is available
-  --readline-dir=DIR     Specify parent of readline include and lib directories
-  --readline-inc-dir=DIR Specify where readline include directory is
-  --readline-lib-dir=DIR Specify where readline lib directory is
+  --with-readline-includes=DIR Specify where readline include directory is
+  --with-readline-library=DIR Specify where readline lib directory is
   --with-ncurses-library=DIR Specify where ncurses lib directory is
   --disable-sechash      Disable support for hashes other than MD5
+  --without-nettle       Don't use nettle even if it is available
   --without-nss          Don't use NSS even if it is available
   --without-tomcrypt     Don't use libtomcrypt even if it is available
+  --disable-nts          Disable NTS support
+  --without-gnutls       Don't use gnutls even if it is available
   --disable-cmdmon       Disable command and monitoring support
   --disable-ntp          Disable NTP support
   --disable-refclock     Disable reference clock support
@@ -95,14 +128,19 @@ For better control, use the options below.
   --disable-rtc          Don't include RTC even on Linux
   --disable-privdrop     Disable support for dropping root privileges
   --without-libcap       Don't use libcap even if it is available
-  --disable-scfilter     Disable support for system call filtering
+  --enable-scfilter      Enable support for system call filtering
   --without-seccomp      Don't use seccomp even if it is available
   --disable-asyncdns     Disable asynchronous name resolving
   --disable-forcednsretry Don't retry on permanent DNS error
+  --without-clock-gettime Don't use clock_gettime() even if it is available
+  --disable-timestamping Disable support for SW/HW timestamping
+  --enable-ntp-signd     Enable support for MS-SNTP authentication in Samba
   --with-ntp-era=SECONDS Specify earliest assumed NTP time in seconds
                          since 1970-01-01 [50*365 days ago]
   --with-user=USER       Specify default chronyd user [root]
   --with-hwclockfile=PATH Specify default path to hwclock(8) adjtime file
+  --with-pidfile=PATH    Specify default pidfile [/var/run/chrony/chronyd.pid]
+  --with-rtcdevice=PATH  Specify default path to RTC device [/dev/rtc]
   --with-sendmail=PATH   Path to sendmail binary [/usr/lib/sendmail]
   --enable-debug         Enable debugging support
 
@@ -111,11 +149,10 @@ Fine tuning of the installation directories:
   --bindir=DIR           user executables [EPREFIX/bin]
   --sbindir=DIR          system admin executables [EPREFIX/sbin]
   --datarootdir=DIR      data root [PREFIX/share]
-  --infodir=DIR          info documentation [DATAROOTDIR/info]
   --mandir=DIR           man documentation [DATAROOTDIR/man]
   --docdir=DIR           documentation root [DATAROOTDIR/doc/chrony]
   --localstatedir=DIR    modifiable single-machine data [/var]
-  --chronysockdir=DIR    location for chrony sockets [LOCALSTATEDIR/run/chrony]
+  --chronyrundir=DIR     location for chrony sockets [LOCALSTATEDIR/run/chrony]
   --chronyvardir=DIR     location for chrony data [LOCALSTATEDIR/lib/chrony]
 
 Overriding system detection when cross-compiling:
@@ -130,6 +167,11 @@ Some influential environment variables:
               headers in a nonstandard directory <include dir>
   LDFLAGS     linker flags, e.g. -L<lib dir> if you have libraries in a
               nonstandard directory <lib dir>
+  PKG_CONFIG  path to pkg-config utility
+  PKG_CONFIG_PATH
+              directories to add to pkg-config's search path
+  PKG_CONFIG_LIBDIR
+              path overriding pkg-config's built-in search path
 
 Use these variables to override the choices made by \`configure' or to help
 it to find libraries and programs with nonstandard names/locations.
@@ -147,13 +189,6 @@ add_def () {
   fi
 }
 #}}}
-#{{{ pkg_config
-pkg_config () {
-  type pkg-config > /dev/null 2> /dev/null || return 1
-
-  pkg-config $@ 2> /dev/null
-}
-#}}}
 #{{{ get_features
 get_features () {
   ff=1
@@ -179,11 +214,11 @@ OPERATINGSYSTEM=`uname -s`
 VERSION=`uname -r`
 MACHINE=`uname -m`
 
+LIBS=""
 EXTRA_LIBS=""
 EXTRA_CLI_LIBS=""
 EXTRA_OBJECTS=""
-EXTRA_DEFS=""
-SYSDEFS=""
+EXTRA_CLI_OBJECTS=""
 
 feat_debug=0
 feat_cmdmon=1
@@ -193,15 +228,19 @@ feat_readline=1
 try_readline=1
 try_editline=1
 feat_sechash=1
+try_nettle=1
 try_nss=1
 try_tomcrypt=1
+feat_nts=1
+try_gnutls=1
 feat_rtc=1
 try_rtc=0
 feat_droproot=1
 try_libcap=-1
 try_clockctl=0
-feat_scfilter=1
+feat_scfilter=0
 try_seccomp=-1
+priv_ops=""
 readline_lib=""
 readline_inc=""
 ncurses_lib=""
@@ -213,9 +252,17 @@ try_setsched=0
 try_lockmem=0
 feat_asyncdns=1
 feat_forcednsretry=1
+try_clock_gettime=1
+try_recvmmsg=1
+feat_timestamping=1
+try_timestamping=0
+feat_ntp_signd=0
 ntp_era_split=""
+use_pthread=0
 default_user="root"
 default_hwclockfile=""
+default_pidfile="/var/run/chrony/chronyd.pid"
+default_rtcdevice="/dev/rtc"
 mail_program="/usr/lib/sendmail"
 
 for option
@@ -260,9 +307,6 @@ do
     --datarootdir=* )
       SETDATAROOTDIR=`echo $option | sed -e 's/^.*=//;'`
     ;;
-    --infodir=* )
-      SETINFODIR=`echo $option | sed -e 's/^.*=//;'`
-    ;;
     --mandir=* )
       SETMANDIR=`echo $option | sed -e 's/^.*=//;'`
     ;;
@@ -272,8 +316,8 @@ do
     --localstatedir=* )
       SETLOCALSTATEDIR=`echo $option | sed -e 's/^.*=//;'`
     ;;
-    --chronysockdir=* )
-      SETCHRONYSOCKDIR=`echo $option | sed -e 's/^.*=//;'`
+    --chronyrundir=* | --chronysockdir=* )
+      SETCHRONYRUNDIR=`echo $option | sed -e 's/^.*=//;'`
     ;;
     --chronyvardir=* )
       SETCHRONYVARDIR=`echo $option | sed -e 's/^.*=//;'`
@@ -305,6 +349,9 @@ do
     --without-libcap|--disable-linuxcaps)
       try_libcap=0
     ;;
+    --enable-scfilter)
+      feat_scfilter=1
+    ;;
     --disable-scfilter)
       feat_scfilter=0
     ;;
@@ -317,6 +364,15 @@ do
     --disable-forcednsretry)
       feat_forcednsretry=0
     ;;
+    --without-clock-gettime)
+      try_clock_gettime=0
+    ;;
+    --disable-timestamping)
+      feat_timestamping=0
+    ;;
+    --enable-ntp-signd)
+      feat_ntp_signd=1
+    ;;
     --with-ntp-era=* )
       ntp_era_split=`echo $option | sed -e 's/^.*=//;'`
     ;;
@@ -326,18 +382,33 @@ do
     --with-hwclockfile=* )
       default_hwclockfile=`echo $option | sed -e 's/^.*=//;'`
     ;;
+    --with-pidfile=* )
+      default_pidfile=`echo $option | sed -e 's/^.*=//;'`
+    ;;
+    --with-rtcdevice=* )
+      default_rtcdevice=`echo $option | sed -e 's/^.*=//;'`
+    ;;
     --with-sendmail=* )
       mail_program=`echo $option | sed -e 's/^.*=//;'`
     ;;
     --disable-sechash )
       feat_sechash=0
     ;;
+    --without-nettle )
+      try_nettle=0
+    ;;
     --without-nss )
       try_nss=0
     ;;
     --without-tomcrypt )
       try_tomcrypt=0
     ;;
+    --disable-nts )
+      feat_nts=0
+    ;;
+    --without-gnutls )
+      try_gnutls=0
+    ;;
     --host-system=* )
       OPERATINGSYSTEM=`echo $option | sed -e 's/^.*=//;'`
     ;;
@@ -362,44 +433,72 @@ SYSTEM=${OPERATINGSYSTEM}-${MACHINE}
 
 case $OPERATINGSYSTEM in
     Linux)
-        EXTRA_OBJECTS="sys_generic.o sys_linux.o sys_timex.o"
+        EXTRA_OBJECTS="sys_generic.o sys_linux.o sys_timex.o sys_posix.o"
         [ $try_libcap != "0" ] && try_libcap=1
         try_rtc=1
         [ $try_seccomp != "0" ] && try_seccomp=1
+        try_timestamping=1
         try_setsched=1
         try_lockmem=1
         try_phc=1
         add_def LINUX
         echo "Configuring for " $SYSTEM
     ;;
-
     FreeBSD)
-        EXTRA_OBJECTS="sys_generic.o sys_netbsd.o sys_timex.o"
+        # recvmmsg() seems to be broken on FreeBSD 11.0 and it's just
+        # a wrapper around recvmsg()
+        try_recvmmsg=0
+        EXTRA_OBJECTS="sys_generic.o sys_netbsd.o sys_timex.o sys_posix.o"
+        try_setsched=1
+        try_lockmem=1
         add_def FREEBSD
+        if [ $feat_droproot = "1" ]; then
+          add_def FEAT_PRIVDROP
+          priv_ops="ADJUSTTIME ADJUSTTIMEX SETTIME BINDSOCKET"
+        fi
         echo "Configuring for $SYSTEM"
     ;;
     NetBSD)
-        EXTRA_OBJECTS="sys_generic.o sys_netbsd.o sys_timex.o"
+        EXTRA_OBJECTS="sys_generic.o sys_netbsd.o sys_timex.o sys_posix.o"
         try_clockctl=1
+        try_setsched=1
+        try_lockmem=1
         add_def NETBSD
         echo "Configuring for $SYSTEM"
     ;;
     Darwin)
         EXTRA_OBJECTS="sys_macosx.o"
-        EXTRA_LIBS="-lresolv"
-        EXTRA_CLI_LIBS="-lresolv"
+        LIBS="$LIBS -lresolv"
         add_def MACOSX
-        echo "Configuring for MacOS X (" $SYSTEM "MacOS X version" $VERSION ")"
+        if [ $feat_droproot = "1" ]; then
+          add_def FEAT_PRIVDROP
+          priv_ops="ADJUSTTIME SETTIME BINDSOCKET"
+        fi
+        major=`echo $VERSION | cut -d. -f1`
+        # ntp_adjtime is not available in macOS 10.12 (Darwin 16.x.x) and earlier
+        if [ $major -gt "16" ]; then
+          add_def HAVE_MACOS_SYS_TIMEX
+          EXTRA_OBJECTS="$EXTRA_OBJECTS sys_generic.o sys_netbsd.o sys_timex.o"
+          if [ $feat_droproot = "1" ]; then
+            priv_ops="$priv_ops ADJUSTTIMEX"
+          fi
+        fi
+        echo "Configuring for macOS (" $SYSTEM "macOS version" $VERSION ")"
     ;;
     SunOS)
-        EXTRA_OBJECTS="sys_generic.o sys_solaris.o sys_timex.o"
-        EXTRA_LIBS="-lsocket -lnsl -lresolv"
-        EXTRA_CLI_LIBS="-lsocket -lnsl -lresolv"
+        EXTRA_OBJECTS="sys_generic.o sys_solaris.o sys_timex.o sys_posix.o"
+        LIBS="$LIBS -lsocket -lnsl -lresolv"
+        try_setsched=1
+        try_lockmem=1
         add_def SOLARIS
         # These are needed to have msg_control in struct msghdr
         add_def __EXTENSIONS__
         add_def _XOPEN_SOURCE 1
         add_def _XOPEN_SOURCE_EXTENDED 1
+        if [ $feat_droproot = "1" ]; then
+          add_def FEAT_PRIVDROP
+          priv_ops="ADJUSTTIMEX SETTIME BINDSOCKET"
+        fi
         echo "Configuring for Solaris (" $SYSTEM "SunOS version" $VERSION ")" 
     ;;                                                                        
     * )
@@ -420,9 +519,14 @@ fi
 
 if [ $feat_ntp = "1" ]; then
   add_def FEAT_NTP
-  EXTRA_OBJECTS="$EXTRA_OBJECTS ntp_core.o ntp_io.o ntp_sources.o"
+  EXTRA_OBJECTS="$EXTRA_OBJECTS ntp_auth.o ntp_core.o ntp_ext.o ntp_io.o ntp_sources.o"
+  if [ $feat_ntp_signd = "1" ]; then
+    add_def FEAT_SIGND
+    EXTRA_OBJECTS="$EXTRA_OBJECTS ntp_signd.o"
+  fi
 else
   feat_asyncdns=0
+  feat_timestamping=0
 fi
 
 if [ "$feat_cmdmon" = "1" ] || [ $feat_ntp = "1" ]; then
@@ -442,14 +546,16 @@ MYCPPFLAGS="$CPPFLAGS"
 MYLDFLAGS="$LDFLAGS"
 
 if [ "x$MYCC" = "x" ]; then
-  MYCC=gcc
-  if ! test_code "$MYCC" '' '' '' ''; then
-    MYCC=cc
-    if ! test_code "$MYCC" '' '' '' ''; then
+  for cc in gcc clang cc ""; do
+    if [ "x$cc" = "x" ]; then
       echo "error: no C compiler found"
       exit 1
     fi
-  fi
+    MYCC=$cc
+    if test_code "$MYCC" '' '' '' ''; then
+      break
+    fi
+  done
 else
   if ! test_code "$MYCC" '' '' '' ''; then
     echo "error: C compiler $MYCC cannot create executables"
@@ -459,12 +565,38 @@ fi
 
 if [ "x$MYCFLAGS" = "x" ]; then
   MYCFLAGS="-O2 -g"
+
+  TESTCFLAGS="-D_FORTIFY_SOURCE=2 -fPIE"
+  TESTLDFLAGS="-pie -Wl,-z,relro,-z,now"
+  if test_code 'hardening compiler options' '' "$TESTCFLAGS" "$TESTLDFLAGS" ''; then
+    MYCFLAGS="$MYCFLAGS $TESTCFLAGS"
+    MYLDFLAGS="$MYLDFLAGS $TESTLDFLAGS"
+  fi
+  TESTCFLAGS="-fstack-protector-strong --param=ssp-buffer-size=4"
+  if test_code '-fstack-protector-strong' '' "$TESTCFLAGS" '' ''; then
+    MYCFLAGS="$MYCFLAGS $TESTCFLAGS"
+  else
+    TESTCFLAGS="-fstack-protector --param=ssp-buffer-size=4"
+    if test_code '-fstack-protector' '' "$TESTCFLAGS" '' ''; then
+      MYCFLAGS="$MYCFLAGS $TESTCFLAGS"
+    fi
+  fi
 fi
 
-if [ "x$MYCC" = "xgcc" ]; then
+if [ "x$MYCC" = "xgcc" ] || [ "x$MYCC" = "xclang" ]; then
   MYCFLAGS="$MYCFLAGS -Wmissing-prototypes -Wall"
 fi
 
+if [ "x$PKG_CONFIG" = "x" ]; then
+  PKG_CONFIG=pkg-config
+fi
+
+if ! test_executable "pkg-config" $PKG_CONFIG --version; then
+  try_nettle=0
+  try_nss=0
+  try_gnutls=0
+fi
+
 if test_code '64-bit time_t' 'time.h' '' '' '
   char x[sizeof(time_t) > 4 ? 1 : -1] = {0};
   return x[0];'
@@ -475,8 +607,12 @@ then
     split_seconds=$ntp_era_split
     split_days=0
   else
-    split_seconds=`date '+%s'`
-    if [ "x$split_seconds" = "" ]; then
+    if [ "x$SOURCE_DATE_EPOCH" != "x" ]; then
+      split_seconds=$SOURCE_DATE_EPOCH
+    else
+      split_seconds=`date '+%s'`
+    fi
+    if [ "x$split_seconds" = "x" ]; then
       echo "error: could not get current time, --with-ntp-era option is needed"
       exit 1
     fi
@@ -500,40 +636,37 @@ then
 fi
 
 MATHCODE='return (int) pow(2.0, log(sqrt((double)argc)));'
-if test_code 'math' 'math.h' '' '' "$MATHCODE"; then
-  LIBS=""
-else
+if ! test_code 'math' 'math.h' '' '' "$MATHCODE"; then
   if test_code 'math in -lm' 'math.h' '' '-lm' "$MATHCODE"; then
-    LIBS="-lm"
+    LIBS="$LIBS -lm"
   else
     echo "error: could not compile/link a program which uses sqrt(), log(), pow()"
     exit 1
   fi
 fi
   
-if test_code '<stdint.h>' 'stdint.h' '' '' ''; then
-  add_def HAVE_STDINT_H
-fi
-
-if test_code '<inttypes.h>' 'inttypes.h' '' '' ''; then
-  add_def HAVE_INTTYPES_H
+if test_code 'struct in_pktinfo' 'sys/socket.h netinet/in.h' '' '' '
+  struct in_pktinfo ipi;
+  return sizeof (ipi.ipi_spec_dst.s_addr) + IP_PKTINFO;'
+then
+  add_def HAVE_IN_PKTINFO
 fi
 
 if [ $feat_ipv6 = "1" ] && \
-  test_code 'IPv6 support' 'arpa/inet.h sys/socket.h netinet/in.h' '' "$EXTRA_LIBS" '
+  test_code 'IPv6 support' 'arpa/inet.h sys/socket.h netinet/in.h' '' "$LIBS" '
     struct sockaddr_in6 n;
     char p[100];
     n.sin6_addr = in6addr_any;
     return !inet_ntop(AF_INET6, &n.sin6_addr.s6_addr, p, sizeof(p));'
 then
   add_def FEAT_IPV6
-  if test_code 'in6_pktinfo' 'sys/socket.h netinet/in.h' '' '' '
-    return sizeof(struct in6_pktinfo);'
+  if test_code 'struct in6_pktinfo' 'sys/socket.h netinet/in.h' '' '' '
+    return sizeof (struct in6_pktinfo) + IPV6_PKTINFO;'
   then
     add_def HAVE_IN6_PKTINFO
   else
-    if test_code 'in6_pktinfo with _GNU_SOURCE' 'sys/socket.h netinet/in.h' \
-      '-D_GNU_SOURCE' '' 'return sizeof(struct in6_pktinfo);'
+    if test_code 'struct in6_pktinfo with _GNU_SOURCE' 'sys/socket.h netinet/in.h' \
+      '-D_GNU_SOURCE' '' 'return sizeof (struct in6_pktinfo) + IPV6_PKTINFO;'
     then
       add_def _GNU_SOURCE
       add_def HAVE_IN6_PKTINFO
@@ -541,29 +674,95 @@ then
   fi
 fi
 
-if test_code 'getaddrinfo()' 'sys/types.h sys/socket.h netdb.h' '' "$EXTRA_LIBS" \
+if [ $try_clock_gettime = "1" ]; then
+  if test_code 'clock_gettime()' 'time.h' '' '' \
+    'clock_gettime(CLOCK_REALTIME, NULL);'
+  then
+    add_def HAVE_CLOCK_GETTIME
+  else
+    if test_code 'clock_gettime() in -lrt' 'time.h' '' '-lrt' \
+      'clock_gettime(CLOCK_REALTIME, NULL);'
+    then
+      add_def HAVE_CLOCK_GETTIME
+      EXTRA_LIBS="$EXTRA_LIBS -lrt"
+    fi
+  fi
+fi
+
+if test_code 'getaddrinfo()' 'sys/types.h sys/socket.h netdb.h' '' "$LIBS" \
   'return getaddrinfo(0, 0, 0, 0);'
 then
   add_def HAVE_GETADDRINFO
 fi
 
 if [ $feat_asyncdns = "1" ] && \
-  test_code 'pthread' 'pthread.h' '-pthread' '' \
-    'return pthread_create((void *)1, NULL, (void *)1, NULL);'
+  test_code 'pthread' 'pthread.h' '-pthread' '' '
+    pthread_t thread;
+    return (int)pthread_create(&thread, NULL, (void *)1, NULL);'
 then
   add_def FEAT_ASYNCDNS
   add_def USE_PTHREAD_ASYNCDNS
   EXTRA_OBJECTS="$EXTRA_OBJECTS nameserv_async.o"
-  MYCFLAGS="$MYCFLAGS -pthread"
+  use_pthread=1
+fi
+
+if test_code 'arc4random_buf()' 'stdlib.h' '' '' 'arc4random_buf(NULL, 0);'; then
+  add_def HAVE_ARC4RANDOM
+fi
+
+if test_code 'getrandom()' 'stdlib.h sys/random.h' '' '' \
+    'return getrandom(NULL, 256, 0);'; then
+  add_def HAVE_GETRANDOM
+fi
+
+RECVMMSG_CODE='
+  struct mmsghdr hdr;
+  return !recvmmsg(0, &hdr, 1, MSG_DONTWAIT, 0);'
+if [ $try_recvmmsg = "1" ]; then
+  if test_code 'recvmmsg()' 'sys/socket.h' '' "$LIBS" "$RECVMMSG_CODE"; then
+    add_def HAVE_RECVMMSG
+  else
+    if test_code 'recvmmsg() with _GNU_SOURCE' 'sys/socket.h' '-D_GNU_SOURCE' \
+      "$LIBS" "$RECVMMSG_CODE"
+    then
+      add_def _GNU_SOURCE
+      add_def HAVE_RECVMMSG
+    fi
+  fi
+fi
+
+if [ $feat_timestamping = "1" ] && [ $try_timestamping = "1" ] &&
+  test_code 'SW/HW timestamping' 'sys/types.h sys/socket.h linux/net_tstamp.h
+                                  linux/errqueue.h linux/ptp_clock.h' '' '' '
+    int val = SOF_TIMESTAMPING_SOFTWARE | SOF_TIMESTAMPING_RX_SOFTWARE |
+              SOF_TIMESTAMPING_RAW_HARDWARE | SOF_TIMESTAMPING_OPT_CMSG;
+    return sizeof (struct scm_timestamping) + SCM_TSTAMP_SND + PTP_SYS_OFFSET +
+           setsockopt(0, SOL_SOCKET, SO_SELECT_ERR_QUEUE + SO_TIMESTAMPING,
+                      &val, sizeof (val));'
+then
+  add_def HAVE_LINUX_TIMESTAMPING
+  EXTRA_OBJECTS="$EXTRA_OBJECTS hwclock.o ntp_io_linux.o"
+
+  if test_code 'other timestamping options' \
+    'sys/types.h sys/socket.h linux/net_tstamp.h' '' '' '
+    struct scm_ts_pktinfo pktinfo;
+    pktinfo.if_index = pktinfo.pkt_length = 0;
+    return pktinfo.if_index + pktinfo.pkt_length + HWTSTAMP_FILTER_NTP_ALL +
+           SCM_TIMESTAMPING_PKTINFO +
+           SOF_TIMESTAMPING_OPT_PKTINFO + SOF_TIMESTAMPING_OPT_TX_SWHW;'; then
+    add_def HAVE_LINUX_TIMESTAMPING_RXFILTER_NTP 1
+    add_def HAVE_LINUX_TIMESTAMPING_OPT_PKTINFO 1
+    add_def HAVE_LINUX_TIMESTAMPING_OPT_TX_SWHW 1
+  fi
 fi
 
 timepps_h=""
 if [ $feat_refclock = "1" ] && [ $feat_pps = "1" ]; then
-  if test_code '<sys/timepps.h>' 'sys/timepps.h' '' '' ''; then
+  if test_code '<sys/timepps.h>' 'inttypes.h time.h sys/timepps.h' '' '' ''; then
     timepps_h="sys/timepps.h"
     add_def HAVE_SYS_TIMEPPS_H
   else
-    if test_code '<timepps.h>' 'timepps.h' '' '' ''; then
+    if test_code '<timepps.h>' 'inttypes.h time.h timepps.h' '' '' ''; then
       timepps_h="timepps.h"
       add_def HAVE_TIMEPPS_H
     fi
@@ -571,10 +770,11 @@ if [ $feat_refclock = "1" ] && [ $feat_pps = "1" ]; then
 fi
 
 if [ "x$timepps_h" != "x" ] && \
-  test_code 'PPSAPI' "string.h $timepps_h" '' '' '
+  test_code 'PPSAPI' "inttypes.h string.h time.h $timepps_h" '' '' '
     pps_handle_t h = 0;
     pps_info_t i;
     struct timespec ts;
+    ts.tv_sec = ts.tv_nsec = 0;
     return time_pps_fetch(h, PPS_TSFMT_TSPEC, &i, &ts);'
 then
   add_def FEAT_PPS
@@ -595,6 +795,7 @@ if [ $feat_droproot = "1" ] && [ $try_clockctl = "1" ] && \
   test_code '<sys/clockctl.h>' 'sys/clockctl.h' '' '' ''
 then
   add_def FEAT_PRIVDROP
+  priv_ops="BINDSOCKET"
 fi
 
 if [ $feat_scfilter = "1" ] && [ $try_seccomp = "1" ] && \
@@ -602,9 +803,21 @@ if [ $feat_scfilter = "1" ] && [ $try_seccomp = "1" ] && \
     'seccomp_init(SCMP_ACT_KILL);'
 then
   add_def FEAT_SCFILTER
+  # NAME2IPADDRESS shouldn't be enabled with other operations as the helper
+  # process works on one request at the time and the async resolver could
+  # block the main thread
+  priv_ops="NAME2IPADDRESS RELOADDNS"
   EXTRA_LIBS="$EXTRA_LIBS -lseccomp"
 fi
 
+if [ "x$priv_ops" != "x" ]; then
+  EXTRA_OBJECTS="$EXTRA_OBJECTS privops.o"
+  add_def PRIVOPS_HELPER
+  for o in $priv_ops; do
+    add_def PRIVOPS_$o
+  done
+fi
+
 if [ $feat_rtc = "1" ] && [ $try_rtc = "1" ] && \
   test_code '<linux/rtc.h>' 'sys/ioctl.h linux/rtc.h' '' '' \
     'ioctl(1, RTC_UIE_ON&RTC_UIE_OFF&RTC_RD_TIME&RTC_SET_TIME, 0&RTC_UF);'
@@ -614,49 +827,51 @@ then
 fi
 
 if [ $feat_refclock = "1" ] && [ $feat_phc = "1" ] && [ $try_phc = "1" ] && \
+  grep '#define HAVE_CLOCK_GETTIME' config.h > /dev/null && \
   test_code '<linux/ptp_clock.h>' 'sys/ioctl.h linux/ptp_clock.h' '' '' \
-    'ioctl(1, PTP_CLOCK_GETCAPS, 0);'
+    'ioctl(1, PTP_CLOCK_GETCAPS + PTP_SYS_OFFSET, 0);'
 then
-  if test_code 'clock_gettime()' 'time.h' '' '' 'clock_gettime(0, NULL);'; then
-    add_def FEAT_PHC
-  else
-    if test_code 'clock_gettime() in -lrt' 'time.h' '' '-lrt' \
-      'clock_gettime(0, NULL);'
-    then
-      EXTRA_LIBS="$EXTRA_LIBS -lrt"
-      add_def FEAT_PHC
-    fi
-  fi
+  grep 'HAVE_LINUX_TIMESTAMPING' config.h > /dev/null ||
+    EXTRA_OBJECTS="$EXTRA_OBJECTS hwclock.o"
+  add_def FEAT_PHC
 fi
 
 if [ $try_setsched = "1" ] && \
   test_code \
-    'sched_setscheduler()' \
-    'sched.h' '' '' '
+    'pthread_setschedparam()' \
+    'pthread.h sched.h' '-pthread' '' '
      struct sched_param sched;
      sched_get_priority_max(SCHED_FIFO);
-     sched_setscheduler(0, SCHED_FIFO, &sched);'
+     pthread_setschedparam(pthread_self(), SCHED_FIFO, &sched);'
 then
-  add_def HAVE_SCHED_SETSCHEDULER
+  add_def HAVE_PTHREAD_SETSCHEDPARAM
+  use_pthread=1
 fi
 
 if [ $try_lockmem = "1" ] && \
   test_code \
     'mlockall()' \
-    'sys/mman.h sys/resource.h' '' '' '
-     struct rlimit rlim;
-     setrlimit(RLIMIT_MEMLOCK, &rlim);
+    'sys/mman.h' '' '' '
      mlockall(MCL_CURRENT|MCL_FUTURE);'
 then
   add_def HAVE_MLOCKALL
 fi
+if [ $try_lockmem = "1" ] && \
+  test_code \
+    'setrlimit(RLIMIT_MEMLOCK, ...)' \
+    'sys/resource.h' '' '' '
+     struct rlimit rlim;
+     rlim.rlim_max = rlim.rlim_cur = RLIM_INFINITY;
+     setrlimit(RLIMIT_MEMLOCK, &rlim);'
+then
+  add_def HAVE_SETRLIMIT_MEMLOCK
+fi
 
 if [ $feat_forcednsretry = "1" ]
 then
   add_def FORCE_DNSRETRY
 fi
 
-READLINE_COMPILE=""
 READLINE_LINK=""
 if [ $feat_readline = "1" ]; then
   if [ $try_editline = "1" ]; then
@@ -666,7 +881,7 @@ if [ $feat_readline = "1" ]; then
     then
       add_def FEAT_READLINE
       add_def USE_EDITLINE
-      READLINE_COMPILE="$readline_inc"
+      MYCPPFLAGS="$MYCPPFLAGS $readline_inc"
       READLINE_LINK="$readline_lib -ledit"
     fi
   fi
@@ -677,7 +892,7 @@ if [ $feat_readline = "1" ]; then
       'add_history(readline("prompt"));'
     then
       add_def FEAT_READLINE
-      READLINE_COMPILE="$readline_inc"
+      MYCPPFLAGS="$MYCPPFLAGS $readline_inc"
       READLINE_LINK="$readline_lib -lreadline"
     fi
   fi
@@ -689,7 +904,7 @@ if [ $feat_readline = "1" ]; then
       'add_history(readline("prompt"));'
     then
       add_def FEAT_READLINE
-      READLINE_COMPILE="$readline_inc"
+      MYCPPFLAGS="$MYCPPFLAGS $readline_inc"
       READLINE_LINK="$readline_lib $ncurses_lib -lreadline -lncurses"
     fi
   fi
@@ -698,10 +913,31 @@ if [ $feat_readline = "1" ]; then
 fi
 
 HASH_OBJ="hash_intmd5.o"
-HASH_COMPILE=""
 HASH_LINK=""
 
-if [ $feat_sechash = "1" ] && [ $try_nss = "1" ]; then
+if [ $feat_sechash = "1" ] && [ "x$HASH_LINK" = "x" ]  && [ $try_nettle = "1" ]; then
+  test_cflags="`pkg_config --cflags nettle`"
+  test_link="`pkg_config --libs nettle`"
+  if test_code 'nettle' 'nettle/nettle-meta.h nettle/sha2.h' \
+    "$test_cflags" "$test_link" \
+    'return nettle_hashes[0]->context_size;'
+  then
+    HASH_OBJ="hash_nettle.o"
+    HASH_LINK="$test_link"
+    MYCPPFLAGS="$MYCPPFLAGS $test_cflags"
+    add_def FEAT_SECHASH
+
+    if test_code 'CMAC in nettle' 'nettle/cmac.h' "$test_cflags" "$test_link" \
+      'cmac128_update(NULL, NULL, NULL, 0, NULL);'
+    then
+      add_def HAVE_CMAC
+      EXTRA_OBJECTS="$EXTRA_OBJECTS cmac_nettle.o"
+      EXTRA_CLI_OBJECTS="$EXTRA_CLI_OBJECTS cmac_nettle.o"
+    fi
+  fi
+fi
+
+if [ $feat_sechash = "1" ] && [ "x$HASH_LINK" = "x" ]  && [ $try_nss = "1" ]; then
   test_cflags="`pkg_config --cflags nss`"
   test_link="`pkg_config --libs-only-L nss` -lfreebl3"
   if test_code 'NSS' 'nss.h hasht.h nsslowhash.h' \
@@ -709,9 +945,8 @@ if [ $feat_sechash = "1" ] && [ $try_nss = "1" ]; then
     'NSSLOWHASH_Begin(NSSLOWHASH_NewContext(NSSLOW_Init(), HASH_AlgSHA512));'
   then
     HASH_OBJ="hash_nss.o"
-    HASH_COMPILE="$test_cflags"
     HASH_LINK="$test_link"
-    LIBS="$LIBS $HASH_LINK"
+    MYCPPFLAGS="$MYCPPFLAGS $test_cflags"
     add_def FEAT_SECHASH
   fi
 fi
@@ -721,13 +956,49 @@ if [ $feat_sechash = "1" ] && [ "x$HASH_LINK" = "x" ] && [ $try_tomcrypt = "1" ]
     'hash_memory_multi(find_hash("md5"), NULL, NULL, NULL, 0, NULL, 0);'
   then
     HASH_OBJ="hash_tomcrypt.o"
-    HASH_COMPILE="-I/usr/include/tomcrypt"
     HASH_LINK="-ltomcrypt"
-    LIBS="$LIBS $HASH_LINK"
+    MYCPPFLAGS="$MYCPPFLAGS -I/usr/include/tomcrypt"
     add_def FEAT_SECHASH
   fi
 fi
 
+EXTRA_OBJECTS="$EXTRA_OBJECTS $HASH_OBJ"
+EXTRA_CLI_OBJECTS="$EXTRA_CLI_OBJECTS $HASH_OBJ"
+LIBS="$LIBS $HASH_LINK"
+
+if [ $feat_ntp = "1" ] && [ $feat_nts = "1" ] && [ $try_gnutls = "1" ] && \
+    echo "$HASH_LINK" | grep 'nettle' > /dev/null; then
+  test_cflags="`pkg_config --cflags gnutls`"
+  test_link="`pkg_config --libs gnutls`"
+  if test_code 'gnutls' 'gnutls/gnutls.h' \
+    "$test_cflags" "$test_link" '
+      return gnutls_init(NULL, 0) +
+        gnutls_priority_init2(NULL, "", NULL, GNUTLS_PRIORITY_INIT_DEF_APPEND) +
+        gnutls_prf_rfc5705(NULL, 0, "", 0, "", 16, NULL);' &&
+    test_code 'AES128 in nettle' 'nettle/aes.h' '' "$LIBS" \
+      'aes128_set_encrypt_key(NULL, NULL);'
+  then
+    EXTRA_OBJECTS="$EXTRA_OBJECTS nts_ke_client.o nts_ke_server.o nts_ke_session.o"
+    EXTRA_OBJECTS="$EXTRA_OBJECTS nts_ntp_auth.o nts_ntp_client.o nts_ntp_server.o"
+    EXTRA_OBJECTS="$EXTRA_OBJECTS siv_nettle.o"
+    LIBS="$LIBS $test_link"
+    MYCPPFLAGS="$MYCPPFLAGS $test_cflags"
+    add_def FEAT_NTS
+
+    add_def HAVE_SIV
+    if test_code 'SIV in nettle' \
+      'nettle/siv-cmac.h' "" "$LIBS" \
+      'siv_cmac_aes128_set_key(NULL, NULL);'
+    then
+      add_def HAVE_NETTLE_SIV_CMAC
+    fi
+  fi
+fi
+
+if [ $use_pthread = "1" ]; then
+  MYCFLAGS="$MYCFLAGS -pthread"
+fi
+
 SYSCONFDIR=/etc
 if [ "x$SETSYSCONFDIR" != "x" ]; then
   SYSCONFDIR=$SETSYSCONFDIR
@@ -758,11 +1029,6 @@ if [ "x$SETDATAROOTDIR" != "x" ]; then
   DATAROOTDIR=$SETDATAROOTDIR
 fi
 
-INFODIR=${DATAROOTDIR}/info
-if [ "x$SETINFODIR" != "x" ]; then
-  INFODIR=$SETINFODIR
-fi
-
 MANDIR=${DATAROOTDIR}/man
 if [ "x$SETMANDIR" != "x" ]; then
   MANDIR=$SETMANDIR
@@ -778,9 +1044,9 @@ if [ "x$SETLOCALSTATEDIR" != "x" ]; then
   LOCALSTATEDIR=$SETLOCALSTATEDIR
 fi
 
-CHRONYSOCKDIR=${LOCALSTATEDIR}/run/chrony
-if [ "x$SETCHRONYSOCKDIR" != "x" ]; then
-  CHRONYSOCKDIR=$SETCHRONYSOCKDIR
+CHRONYRUNDIR=${LOCALSTATEDIR}/run/chrony
+if [ "x$SETCHRONYRUNDIR" != "x" ]; then
+  CHRONYRUNDIR=$SETCHRONYRUNDIR
 fi
 
 CHRONYVARDIR=${LOCALSTATEDIR}/lib/chrony
@@ -790,48 +1056,52 @@ fi
 
 add_def DEFAULT_CONF_FILE "\"$SYSCONFDIR/chrony.conf\""
 add_def DEFAULT_HWCLOCK_FILE "\"$default_hwclockfile\""
+add_def DEFAULT_PID_FILE "\"$default_pidfile\""
+add_def DEFAULT_RTC_DEVICE "\"$default_rtcdevice\""
 add_def DEFAULT_USER "\"$default_user\""
-add_def DEFAULT_COMMAND_SOCKET "\"$CHRONYSOCKDIR/chronyd.sock\""
+add_def DEFAULT_COMMAND_SOCKET "\"$CHRONYRUNDIR/chronyd.sock\""
 add_def MAIL_PROGRAM "\"$mail_program\""
 
-common_features="`get_features IPV6 DEBUG`"
+common_features="`get_features SECHASH IPV6 DEBUG`"
 chronyc_features="`get_features READLINE`"
-chronyd_features="`get_features CMDMON NTP REFCLOCK RTC PRIVDROP SCFILTER SECHASH ASYNCDNS`"
+chronyd_features="`get_features CMDMON NTP REFCLOCK RTC PRIVDROP SCFILTER SIGND ASYNCDNS NTS`"
 add_def CHRONYC_FEATURES "\"$chronyc_features $common_features\""
 add_def CHRONYD_FEATURES "\"$chronyd_features $common_features\""
 echo "Features : $chronyd_features $chronyc_features $common_features"
 
 if [ -f version.txt ]; then
-  add_def CHRONY_VERSION "\"`cat version.txt`\""
+  CHRONY_VERSION="`cat version.txt`"
 else
-  add_def CHRONY_VERSION "\"DEVELOPMENT\""
+  CHRONY_VERSION="DEVELOPMENT"
 fi
 
-for f in Makefile chrony.conf.5 chrony.texi chronyc.1 chronyd.8
+add_def CHRONY_VERSION "\"${CHRONY_VERSION}\""
+
+for f in Makefile doc/Makefile test/unit/Makefile
 do
   echo Creating $f
-  sed -e "s%@EXTRA_OBJECTS@%${EXTRA_OBJECTS}%;\
+  sed -e "s%@EXTRA_OBJS@%${EXTRA_OBJECTS}%;\
+          s%@EXTRA_CLI_OBJS@%${EXTRA_CLI_OBJECTS}%;\
           s%@CC@%${MYCC}%;\
           s%@CFLAGS@%${MYCFLAGS}%;\
           s%@CPPFLAGS@%${MYCPPFLAGS}%;\
-          s%@LIBS@%${LIBS}%;\
           s%@LDFLAGS@%${MYLDFLAGS}%;\
+          s%@LIBS@%${LIBS}%;\
           s%@EXTRA_LIBS@%${EXTRA_LIBS}%;\
           s%@EXTRA_CLI_LIBS@%${EXTRA_CLI_LIBS}%;\
-          s%@READLINE_COMPILE@%${READLINE_COMPILE}%;\
-          s%@HASH_OBJ@%${HASH_OBJ}%;\
-          s%@HASH_COMPILE@%${HASH_COMPILE}%;\
           s%@SYSCONFDIR@%${SYSCONFDIR}%;\
           s%@BINDIR@%${BINDIR}%;\
           s%@SBINDIR@%${SBINDIR}%;\
           s%@DOCDIR@%${DOCDIR}%;\
           s%@MANDIR@%${MANDIR}%;\
-          s%@INFODIR@%${INFODIR}%;\
           s%@LOCALSTATEDIR@%${LOCALSTATEDIR}%;\
-          s%@CHRONYSOCKDIR@%${CHRONYSOCKDIR}%;\
+          s%@CHRONYRUNDIR@%${CHRONYRUNDIR}%;\
           s%@CHRONYVARDIR@%${CHRONYVARDIR}%;\
           s%@DEFAULT_HWCLOCK_FILE@%${default_hwclockfile}%;\
-          s%@DEFAULT_USER@%${default_user}%;"\
+          s%@DEFAULT_PID_FILE@%${default_pidfile}%;\
+          s%@DEFAULT_RTC_DEVICE@%${default_rtcdevice}%;\
+          s%@DEFAULT_USER@%${default_user}%;\
+          s%@CHRONY_VERSION@%${CHRONY_VERSION}%;" \
           < ${f}.in > $f
 done
 

contrib/bryan_christianson_1/README.txt

@@ -1,16 +1,16 @@
-Notes for installing chrony on MacOS X
+Notes for installing chrony on macOS
 Author: Bryan Christianson (bryan@whatroute.net)
 ------------------------------------------------
 
 These files are for those admins/users who would prefer to install chrony
 from the source distribution and are intended as guidelines rather than
 being definitive. They can be edited with a plain text editor, such as
-vi, emacs or your favourite IDE (xcode)
+vi, emacs or your favourite IDE (Xcode)
 
 It is assumed you are comfortable with installing software from the
 terminal command line and know how to use sudo to acquire root access.
 
-If you are not familiar with the MacOS X command line then
+If you are not familiar with the macOS command line then
 please consider using ChronyControl from http://whatroute.net/chronycontrol.html
 
 ChronyControl provides a gui wrapper for installing these files and sets the
@@ -72,7 +72,7 @@ Installing the support files
 
 1. chronylogrotate.sh
 This is a simple shell script that deletes old log files. Unfortunately because
-of the need to run chronyc, the standard MacOS X logrotation does not work with
+of the need to run chronyc, the standard macOS logrotation does not work with
 chrony logs.
 
 This script runs on a daily basis under control of launchd and should be

contrib/bryan_christianson_1/chronylogrotate.sh

@@ -1,20 +1,27 @@
 #!/bin/sh
 
-#  chronylogrotate.sh
-#  ChronyControl
-#
-#  Created by Bryan Christianson on 12/07/15.
+#  chronyd/chronyc - Programs for keeping computer clocks accurate.
 #
+#  **********************************************************************
+#  * Copyright (C) Bryan Christianson  2015
+#  *
+#  * This program is free software; you can redistribute it and/or modify
+#  * it under the terms of version 2 of the GNU General Public License as
+#  * published by the Free Software Foundation.
+#  *
+#  * This program is distributed in the hope that it will be useful, but
+#  * WITHOUT ANY WARRANTY; without even the implied warranty of
+#  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  * General Public License for more details.
+#  *
+#  * You should have received a copy of the GNU General Public License along
+#  * with this program; if not, write to the Free Software Foundation, Inc.,
+#  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#  *
+#  **********************************************************************
 
 LOGDIR=/var/log/chrony
 
-if [ ! -e "$LOGDIR" ]; then
-  echo "missing directory: $LOGDIR"
-  exit 1
-fi
-
-cd $LOGDIR
-
 rotate () {
   prefix=$1
 
@@ -33,13 +40,19 @@ rotate () {
   fi
 }
 
+if [ ! -e "$LOGDIR" ]; then
+  logger -s "missing directory: $LOGDIR"
+  exit 1
+fi
+
+cd $LOGDIR
+
 rotate measurements
 rotate statistics
 rotate tracking
 
 #
 # signal chronyd via chronyc
-
-/usr/local/bin/chronyc -a -f /etc/chrony.d/chrony.conf cyclelogs > /dev/null
+/usr/local/bin/chronyc cyclelogs > /dev/null
 
 exit $?

doc/Makefile.in

@@ -0,0 +1,76 @@
+ADOC = asciidoctor
+ADOC_FLAGS =
+SED = sed
+HTML_TO_TXT = w3m -dump -T text/html
+
+MAN_FILES = chrony.conf.man chronyc.man chronyd.man
+TXT_FILES = faq.txt installation.txt
+HTML_FILES = $(MAN_FILES:%.man=%.html) $(TXT_FILES:%.txt=%.html)
+MAN_IN_FILES = $(MAN_FILES:%.man=%.man.in)
+
+SYSCONFDIR = @SYSCONFDIR@
+BINDIR = @BINDIR@
+SBINDIR = @SBINDIR@
+MANDIR = @MANDIR@
+DOCDIR = @DOCDIR@
+CHRONYRUNDIR = @CHRONYRUNDIR@
+CHRONYVARDIR = @CHRONYVARDIR@
+CHRONY_VERSION = @CHRONY_VERSION@
+DEFAULT_USER = @DEFAULT_USER@
+DEFAULT_HWCLOCK_FILE = @DEFAULT_HWCLOCK_FILE@
+DEFAULT_PID_FILE = @DEFAULT_PID_FILE@
+DEFAULT_RTC_DEVICE = @DEFAULT_RTC_DEVICE@
+
+SED_COMMANDS = "s%\@SYSCONFDIR\@%$(SYSCONFDIR)%g;\
+	       s%\@BINDIR\@%$(BINDIR)%g;\
+	       s%\@SBINDIR\@%$(SBINDIR)%g;\
+	       s%\@CHRONY_VERSION\@%$(CHRONY_VERSION)%g;\
+	       s%\@DEFAULT_HWCLOCK_FILE\@%$(DEFAULT_HWCLOCK_FILE)%g;\
+	       s%\@DEFAULT_PID_FILE\@%$(DEFAULT_PID_FILE)%g;\
+	       s%\@DEFAULT_RTC_DEVICE\@%$(DEFAULT_RTC_DEVICE)%g;\
+	       s%\@DEFAULT_USER\@%$(DEFAULT_USER)%g;\
+	       s%\@CHRONYRUNDIR\@%$(CHRONYRUNDIR)%g;\
+	       s%\@CHRONYVARDIR\@%$(CHRONYVARDIR)%g;"
+
+man: $(MAN_FILES) $(MAN_IN_FILES)
+html: $(HTML_FILES)
+txt: $(TXT_FILES)
+docs: man html
+
+%.html: %.adoc
+	$(ADOC) $(ADOC_FLAGS) -b html -o - $< | $(SED) -e $(SED_COMMANDS) > $@
+
+%.man.in: %.adoc
+	$(ADOC) $(ADOC_FLAGS) -b manpage -o $@ $<
+
+%.man: %.man.in
+	$(SED) -e $(SED_COMMANDS) < $< > $@
+
+%.txt: %.html
+	$(HTML_TO_TXT) < $< > $@
+
+install: $(MAN_FILES)
+	[ -d $(DESTDIR)$(MANDIR)/man1 ] || mkdir -p $(DESTDIR)$(MANDIR)/man1
+	[ -d $(DESTDIR)$(MANDIR)/man5 ] || mkdir -p $(DESTDIR)$(MANDIR)/man5
+	[ -d $(DESTDIR)$(MANDIR)/man8 ] || mkdir -p $(DESTDIR)$(MANDIR)/man8
+	cp chronyc.man $(DESTDIR)$(MANDIR)/man1/chronyc.1
+	chmod 644 $(DESTDIR)$(MANDIR)/man1/chronyc.1
+	cp chronyd.man $(DESTDIR)$(MANDIR)/man8/chronyd.8
+	chmod 644 $(DESTDIR)$(MANDIR)/man8/chronyd.8
+	cp chrony.conf.man $(DESTDIR)$(MANDIR)/man5/chrony.conf.5
+	chmod 644 $(DESTDIR)$(MANDIR)/man5/chrony.conf.5
+
+install-docs: $(HTML_FILES)
+	[ -d $(DESTDIR)$(DOCDIR) ] || mkdir -p $(DESTDIR)$(DOCDIR)
+	for f in $(HTML_FILES); do \
+	  cp $$f $(DESTDIR)$(DOCDIR); \
+	  chmod 644 $(DESTDIR)$(DOCDIR)/$$f; \
+	done
+
+clean:
+	rm -f $(MAN_FILES) $(TXT_FILES) $(HTML_FILES)
+	rm -f $(MAN_IN_FILES)
+
+distclean:
+	rm -f $(MAN_FILES) $(TXT_FILES) $(HTML_FILES)
+	rm -f Makefile

doc/chronyd.adoc

@@ -0,0 +1,194 @@
+// This file is part of chrony
+//
+// Copyright (C) Richard P. Curnow  1997-2003
+// Copyright (C) Miroslav Lichvar  2009-2017
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of version 2 of the GNU General Public License as
+// published by the Free Software Foundation.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+= chronyd(8)
+:doctype: manpage
+:man manual: System Administration
+:man source: chrony @CHRONY_VERSION@
+
+== NAME
+
+chronyd - chrony daemon
+
+== SYNOPSIS
+
+*chronyd* [_OPTION_]... [_DIRECTIVE_]...
+
+== DESCRIPTION
+
+*chronyd* is a daemon for synchronisation of the system clock. It can
+synchronise the clock with NTP servers, reference clocks (e.g. a GPS receiver),
+and manual input using wristwatch and keyboard via *chronyc*. It can also
+operate as an NTPv4 (RFC 5905) server and peer to provide a time service to
+other computers in the network.
+
+If no configuration directives are specified on the command line, *chronyd*
+will read them from a configuration file. The compiled-in default location of
+the file is _@SYSCONFDIR@/chrony.conf_.
+
+Informational messages, warnings, and errors will be logged to syslog.
+
+== OPTIONS
+
+*-4*::
+With this option hostnames will be resolved only to IPv4 addresses and only
+IPv4 sockets will be created.
+
+*-6*::
+With this option hostnames will be resolved only to IPv6 addresses and only
+IPv6 sockets will be created.
+
+*-f* _file_::
+This option can be used to specify an alternate location for the configuration
+file. The default value is _@SYSCONFDIR@/chrony.conf_.
+
+*-n*::
+When run in this mode, the program will not detach itself from the terminal.
+
+*-d*::
+When run in this mode, the program will not detach itself from the terminal,
+and all messages will be written to the terminal instead of syslog. If
+*chronyd* was compiled with enabled support for debugging, this option can be
+used twice to enable debug messages.
+
+*-l* _file_::
+This option enables writing of log messages to a file instead of syslog or the
+terminal.
+
+*-L* _level_::
+This option specifies the minimum severity level of messages to be written to
+the log file, syslog, or terminal. The following levels can be specified:
+0 (informational), 1 (warning), 2 (non-fatal error), and 3 (fatal error). The
+default value is 0.
+
+*-q*::
+When run in this mode, *chronyd* will set the system clock once and exit. It
+will not detach from the terminal.
+
+*-Q*::
+This option is similar to the *-q* option, except it only prints the offset
+without making any corrections of the clock and it allows *chronyd* to be
+started without root privileges.
+
+*-r*::
+This option will try to reload and then delete files containing sample
+histories for each of the servers and reference clocks being used. The
+files are expected to be in the directory specified by the
+<<chrony.conf.adoc#dumpdir,*dumpdir*>>
+directive in the configuration file. This option is useful if you want to stop
+and restart *chronyd* briefly for any reason, e.g. to install a new version.
+However, it should be used only on systems where the kernel can maintain clock
+compensation whilst not under *chronyd*'s control (i.e. Linux, FreeBSD, NetBSD,
+Solaris, and macOS 10.13 or later).
+
+*-R*::
+When this option is used, the <<chrony.conf.adoc#initstepslew,*initstepslew*>>
+directive and the <<chrony.conf.adoc#makestep,*makestep*>> directive used with
+a positive limit will be ignored. This option is useful when restarting
+*chronyd* and can be used in conjunction with the *-r* option.
+
+*-s*::
+This option will set the system clock from the computer's real-time clock (RTC)
+or to the last modification time of the file specified by the
+<<chrony.conf.adoc#driftfile,*driftfile*>> directive. Real-time clocks are
+supported only on Linux.
++
+If used in conjunction with the *-r* flag, *chronyd* will attempt to preserve
+the old samples after setting the system clock from the RTC. This can be used
+to allow *chronyd* to perform long term averaging of the gain or loss rate
+across system reboots, and is useful for systems with intermittent access to
+network that are shut down when not in use. For this to work well, it relies
+on *chronyd* having been able to determine accurate statistics for the
+difference between the RTC and system clock last time the computer was on.
++
+If the last modification time of the drift file is later than both the current
+time and the RTC time, the system time will be set to it to restore the time
+when *chronyd* was previously stopped. This is useful on computers that have no
+RTC or the RTC is broken (e.g. it has no battery).
+
+*-t* _timeout_::
+This option sets a timeout (in seconds) after which *chronyd* will exit. If the
+clock is not synchronised, it will exit with a non-zero status. This is useful
+with the *-q* or *-Q* option to shorten the maximum time waiting for
+measurements, or with the *-r* option to limit the time when *chronyd* is
+running, but still allow it to adjust the frequency of the system clock.
+
+*-u* _user_::
+This option sets the name of the system user to which *chronyd* will switch
+after start in order to drop root privileges. It overrides the
+<<chrony.conf.adoc#user,*user*>> directive. The default value is
+_@DEFAULT_USER@_.
++
+On Linux, *chronyd* needs to be compiled with support for the *libcap* library.
+On macOS, FreeBSD, NetBSD and Solaris *chronyd* forks into two processes.
+The child process retains root privileges, but can only perform a very limited
+range of privileged system calls on behalf of the parent.
+
+*-F* _level_::
+This option configures a system call filter when *chronyd* is compiled with
+support for the Linux secure computing (seccomp) facility. In level 1 the
+process is killed when a forbidden system call is made, in level -1 the SIGSYS
+signal is thrown instead and in level 0 the filter is disabled. The default
+value is 0.
++
+It's recommended to enable the filter only when it's known to work on the
+version of the system where *chrony* is installed as the filter needs to allow
+also system calls made from libraries that *chronyd* is using (e.g. libc) and
+different versions or implementations of the libraries may make different
+system calls. If the filter is missing some system call, *chronyd* could be
+killed even in normal operation.
+
+*-P* _priority_::
+On Linux, this option will select the SCHED_FIFO real-time scheduler at the
+specified priority (which must be between 0 and 100). On macOS, this option
+must have either a value of 0 to disable the thread time
+constraint policy or 1 for the policy to be enabled. Other systems do not
+support this option. The default value is 0.
+
+*-m*::
+This option will lock *chronyd* into RAM so that it will never be paged out.
+This mode is only supported on Linux.
+
+*-x*::
+This option disables the control of the system clock. *chronyd* will not try to
+make any adjustments of the clock. It will assume the clock is free running and
+still track its offset and frequency relative to the estimated true time. This
+option allows *chronyd* to run without the capability to adjust or set the
+system clock (e.g. in some containers) in order to operate as an NTP server. It
+is not recommended to run *chronyd* (with or without *-x*) when another process
+is controlling the system clock.
+
+*-v*::
+With this option *chronyd* will print version number to the terminal and exit.
+
+== FILES
+
+_@SYSCONFDIR@/chrony.conf_
+
+== SEE ALSO
+
+<<chronyc.adoc#,*chronyc(1)*>>, <<chrony.conf.adoc#,*chrony.conf(5)*>>
+
+== BUGS
+
+For instructions on how to report bugs, please visit
+https://chrony.tuxfamily.org/.
+
+== AUTHORS
+
+chrony was written by Richard Curnow, Miroslav Lichvar, and others.

doc/faq.adoc

@@ -1,59 +1,91 @@
+// This file is part of chrony
+//
+// Copyright (C) Richard P. Curnow  1997-2003
+// Copyright (C) Miroslav Lichvar  2014-2016
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of version 2 of the GNU General Public License as
+// published by the Free Software Foundation.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+= Frequently Asked Questions
 :toc:
 :numbered:
 
-Frequently Asked Questions
-==========================
+== `chrony` compared to other programs
 
-== +chrony+ compared to other programs
+=== How does `chrony` compare to `ntpd`?
 
-=== How does +chrony+ compare to +ntpd+?
-
-+chronyd+ was designed to work well in a wide range of conditions and it can
-usually synchronise the system clock faster and with better time accuracy.  It
+`chronyd` was designed to work well in a wide range of conditions and it can
+usually synchronise the system clock faster and with better time accuracy. It
 doesn't implement some of the less useful NTP modes like broadcast client or
 multicast server/client.
 
-For a more detailed comparison of features and performance, see the
-http://chrony.tuxfamily.org/comparison.html[comparison page] on the +chrony+
-website and the
-http://chrony.tuxfamily.org/manual.html#Comparison-with-ntpd[Comparison with
-ntpd] section in the manual.
-
-If your computer is connected to the internet only for few minutes at a time,
+If your computer is connected to the Internet only for few minutes at a time,
 the network connection is often congested, you turn your computer off or
 suspend it frequently, the clock is not very stable (e.g. there are rapid
 changes in the temperature or it's a virtual machine), or you want to use NTP
-on an isolated network with no hardware reference clocks in sight, +chrony+
+on an isolated network with no hardware reference clocks in sight, `chrony`
 will probably work much better for you.
 
-The original reason +chrony+ was written was that +ntpd+ (called +xntpd+ at the
-time) could not to do anything sensible on a PC which was connected to the 'net
-only for about 5 minutes once or twice a day, mainly to upload/download email
-and news.  The requirements were
-
-* slew the time to correct it when going online and NTP servers
-  become visible
-* determine the rate at which the computer gains or loses time and
-  use this information to keep it reasonably correct between connects
-  to the 'net.  This has to be done using a method that does not care
-  about the intermittent availability of the references or the fact
-  the computer is turned off between groups of measurements.
-* maintain the time across reboots, by working out the error and
-  drift rate of the computer's real-time clock and using this
-  information to set the system clock correctly at boot up.
-
-Also, when working with isolated networks with no true time references at all
-+ntpd+ was found to give no help with managing the local clock's gain/loss rate
-on the NTP master node (which was set from watch).  Some automated support was
-added to +chrony+ to deal with this.
+For a more detailed comparison of features and performance, see the
+https://chrony.tuxfamily.org/comparison.html[comparison page] on the `chrony`
+website.
 
 == Configuration issues
 
+=== What is the minimum recommended configuration for an NTP client?
+
+First, the client needs to know which NTP servers it should ask for the current
+time. They are specified by the `server` or `pool` directive. The `pool`
+directive can be used for names that resolve to multiple addresses. For good
+reliability the client should have at least three servers. The `iburst` option
+speeds up the initial synchronisation.
+
+To stabilise the initial synchronisation on the next start, the estimated drift
+of the system clock is saved to a file specified by the `driftfile` directive.
+
+If the system clock can be far from the true time after boot for any reason,
+`chronyd` should be allowed to correct it quickly by stepping instead of
+slewing, which would take a very long time. The `makestep` directive does
+that.
+
+In order to keep the real-time clock (RTC) close to the true time, so the
+system time is reasonably close to the true time when it's initialised on the
+next boot from the RTC, the `rtcsync` directive enables a mode in which the
+system time is periodically copied to the RTC. It is supported on Linux and
+macOS.
+
+If you want to use public NTP servers from the
+http://www.pool.ntp.org/[pool.ntp.org] project, the minimal _chrony.conf_ file
+could be:
+
+----
+pool pool.ntp.org iburst
+driftfile /var/lib/chrony/drift
+makestep 1 3
+rtcsync
+----
+
+=== How do I make an NTP server from an NTP client?
+
+You need to add an `allow` directive to the _chrony.conf_ file in order to open
+the NTP port and allow `chronyd` to reply to client requests. `allow` with no
+specified subnet allows access from all IPv4 and IPv6 addresses.
+
 === I have several computers on a LAN. Should be all clients of an external server?
 
-The best configuration is usually to make one computer the master, with
-the others as clients of it.  Add a +local+ directive to the master's
-'chrony.conf' file.  This configuration will be better because
+The best configuration is usually to make one computer the server, with
+the others as clients of it. Add a `local` directive to the server's
+_chrony.conf_ file. This configuration will be better because
 
 * the load on the external connection is less
 * the load on the external NTP server(s) is less
@@ -62,280 +94,476 @@ the others as clients of it.  Add a +local+ directive to the master's
 
 === Must I specify servers by IP address if DNS is not available on chronyd start?
 
-No.  Starting from version 1.25, +chronyd+ will keep trying to resolve
-the hostnames specified in the +server+ and +peer+ directives in
-increasing intervals until it succeeds.  The +online+ command can be
-issued from +chronyc+ to try to resolve them immediately.
+No. Starting from version 1.25, `chronyd` will keep trying to resolve
+the names specified by the `server`, `pool`, and `peer` directives in an
+increasing interval until it succeeds. The `online` command can be issued from
+`chronyc` to force `chronyd` to try to resolve the names immediately.
 
-=== How can I make +chronyd+ more secure?
+=== How can I make `chronyd` more secure?
 
-If you don't need to serve time to NTP clients or peers, you can add +port 0+
-to the 'chrony.conf' file to completely disable the NTP server functionality
-and prevent NTP requests from reaching +chronyd+. Starting from version 2.0,
-the NTP server port is open only when client access is allowed by the +allow+
-directive or command, an NTP peer is configured, or the +broadcast+ directive
+If you don't need to serve time to NTP clients or peers, you can add `port 0`
+to the _chrony.conf_ file to completely disable the NTP server functionality
+and prevent NTP requests from reaching `chronyd`. Starting from version 2.0,
+the NTP server port is open only when client access is allowed by the `allow`
+directive or command, an NTP peer is configured, or the `broadcast` directive
 is used.
 
-If you don't need to use +chronyc+ remotely, you can add the following
+If you don't need to use `chronyc` remotely, you can add the following
 directives to the configuration file to bind the command sockets to the
-loopback interface.  This is done by default since version 2.0.
+loopback interface. This is done by default since version 2.0.
 
 ----
 bindcmdaddress 127.0.0.1
 bindcmdaddress ::1
 ----
 
-If you don't need to use +chronyc+ at all or you need to run +chronyc+ only
-under the root or chrony user (which can access +chronyd+ through a Unix domain
-socket since version 2.2), you can disable the internet command sockets
-completely by adding +cmdport 0+ to the configuration file.
+If you don't need to use `chronyc` at all or you need to run `chronyc` only
+under the root or _chrony_ user (which can access `chronyd` through a Unix
+domain socket since version 2.2), you can disable the internet command sockets
+completely by adding `cmdport 0` to the configuration file.
 
-On Linux, if +chronyd+ is compiled with support for Linux capabilities
-(available in the libcap library), or on NetBSD with the +/dev/clockctl+
-device, you can specify an unprivileged user with the +-u+ option or +user+
-directive in the 'chrony.conf' file to drop root privileges after start.  The
-configure option +--with-user+ can be used to drop the privileges by default.
+You can specify an unprivileged user with the `-u` option, or the `user`
+directive in the _chrony.conf_ file, to which `chronyd` will switch after start
+in order to drop root privileges. The configure script has a `--with-user`
+option, which sets the default user. On Linux, `chronyd` needs to be compiled
+with support for the `libcap` library. On other systems, `chronyd` forks into
+two processes. The child process retains root privileges, but can only perform
+a very limited range of privileged system calls on behalf of the parent.
 
-Also, if +chronyd+ is compiled with support for the Linux secure computing
-(seccomp) facility, you can enable a system call filter with the +-F+ option.
+Also, if `chronyd` is compiled with support for the Linux secure computing
+(seccomp) facility, you can enable a system call filter with the `-F` option.
 It will significantly reduce the kernel attack surface and possibly prevent
-kernel exploits from the +chronyd+ process if compromised.  The filter
-shouldn't be enabled without testing that it allows all system calls needed
-with the specific configuration and libraries that +chronyd+ is using (e.g.
-libc and its NSS configuration).  If +chronyd+ is getting killed, some system
-call is missing and the filter has to be disabled until it's patched to allow
-that call.
+kernel exploits from the `chronyd` process if it's compromised. It's
+recommended to enable the filter only when it's known to work on the version of
+the system where `chrony` is installed as the filter needs to allow also system
+calls made from libraries that `chronyd` is using (e.g. libc) and different
+versions or implementations of the libraries may make different system calls.
+If the filter is missing some system call, `chronyd` could be killed even in
+normal operation.
 
 === How can I improve the accuracy of the system clock with NTP sources?
 
 Select NTP servers that are well synchronised, stable and close to your
-network.  It's better to use more than one server, three or four is usually
-recommended as the minimum, so +chronyd+ can detect falsetickers and combine
-measurements from multiple sources.
+network. It's better to use more than one server, three or four is usually
+recommended as the minimum, so `chronyd` can detect servers that serve false
+time and combine measurements from multiple sources.
 
-There are also useful options which can be set in the +server+ directive, they
-are +minpoll+, +maxpoll+, +polltarget+, +maxdelay+, +maxdelayratio+ and
-+maxdelaydevratio+.
+If you have a network card with hardware timestamping supported on Linux, it
+can be enabled by the *hwtimestamp* directive in the _chrony.conf_ file. It
+should make local receive and transmit timestamps of NTP packets much more
+accurate.
+
+There are also useful options which can be set in the `server` directive, they
+are `minpoll`, `maxpoll`, `polltarget`, `maxdelay`, `maxdelayratio`,
+`maxdelaydevratio`, and `xleave`.
 
 The first three options set the minimum and maximum allowed polling interval,
-and how should be the actual interval adjusted in the specified range.  Their
-default values are 6 (64 seconds) for +minpoll+, 10 (1024 seconds) for
-+maxpoll+ and 6 (samples) for +polltarget+.  The default values should be used
-for general servers on the internet.  With your own NTP servers or if have
+and how should be the actual interval adjusted in the specified range. Their
+default values are 6 (64 seconds) for `minpoll`, 10 (1024 seconds) for
+`maxpoll` and 8 (samples) for `polltarget`. The default values should be used
+for general servers on the Internet. With your own NTP servers, or if you have
 permission to poll some servers more frequently, setting these options for
 shorter polling intervals may significantly improve the accuracy of the system
 clock.
 
-The optimal polling interval depends on many factors, including the ratio
-between the wander of the clock and the network jitter (sometimes expressed in
-NTP documents as the Allan intercept), the temperature sensitivity of the
-crystal oscillator and the maximum rate of change of the temperature.
+The optimal polling interval depends mainly on two factors, stability of the
+network latency and stability of the system clock (which mainly depends on the
+temperature sensitivity of the crystal oscillator and the maximum rate of the
+temperature change).
 
-An example of the directive for an NTP server on the internet that you are
+Generally, if the `sourcestats` command usually reports a small number of
+samples retained for a source (e.g. fewer than 16), a shorter polling interval
+should be considered. If the number of samples is usually at the maximum of 64,
+a longer polling interval may work better.
+
+An example of the directive for an NTP server on the Internet that you are
 allowed to poll frequently could be
 
 ----
 server foo.example.net minpoll 4 maxpoll 6 polltarget 16
 ----
 
-An example using very short polling intervals for a server located in the same
+An example using shorter polling intervals with a server located in the same
 LAN could be
 
 ----
 server ntp.local minpoll 2 maxpoll 4 polltarget 30
 ----
 
-The maxdelay options are useful to ignore measurements with larger delay (e.g.
-due to congestion in the network) and improve the stability of the
-synchronisation.  The +maxdelaydevratio+ option could be added to the example
+The maxdelay options are useful to ignore measurements with an unusally large
+delay (e.g. due to congestion in the network) and improve the stability of the
+synchronisation. The `maxdelaydevratio` option could be added to the example
 with local NTP server
 
 ----
 server ntp.local minpoll 2 maxpoll 4 polltarget 30 maxdelaydevratio 2
 ----
 
-=== What happened to the +commandkey+ and +generatecommandkey+ directives?
+If your server supports the interleaved mode (e.g. it is running `chronyd`),
+the `xleave` option should be added to the `server` directive in order to allow
+the server to send the client more accurate transmit timestamps (kernel or
+preferably hardware). For example:
 
-They were removed in version 2.2.  Authentication is no longer supported in the
-command protocol.  Commands that required authentication are now allowed only
-through a Unix domain socket, which is accessible only by the root and chrony
-users.  If you need to configure +chronyd+ remotely or locally without the root
-password, please consider using ssh and/or sudo to run +chronyc+ under the root
-or chrony user on the same host as +chronyd+ is running.
+----
+server ntp.local minpoll 2 maxpoll 4 xleave
+----
+
+When combined with local hardware timestamping, good network switches, and even
+shorter polling intervals, a sub-microsecond accuracy and stability of a few
+tens of nanoseconds may be possible. For example:
+
+----
+server ntp.local minpoll 0 maxpoll 0 xleave
+hwtimestamp eth0
+----
+
+For best stability, the CPU should be running at a constant frequency (i.e.
+disabled power saving and performance boosting). Energy-Efficient Ethernet
+(EEE) should be disabled in the network. The switches should be configured to
+prioritize NTP packets, especially if the network is expected to be heavily
+loaded.
+
+If it is acceptable for NTP clients in the network to send requests at an
+excessive rate, a sub-second polling interval may be specified. A median filter
+can be enabled in order to update the clock at a reduced rate with more stable
+measurements. For example:
+
+----
+server ntp.local minpoll -6 maxpoll -6 filter 15 xleave
+hwtimestamp eth0 minpoll -6
+----
+
+=== Does `chronyd` have an ntpdate mode?
+
+Yes. With the `-q` option `chronyd` will set the system clock once and exit.
+With the `-Q` option it will print the measured offset without setting the
+clock. If you don't want to use a configuration file, NTP servers can be
+specified on the command line. For example:
+
+----
+# chronyd -q 'pool pool.ntp.org iburst'
+----
+
+The command above would normally take about 5 seconds if the servers were
+well synchronised and responding to all requests. If not synchronised or
+responding, it would take about 10 seconds for `chronyd` to give up and exit
+with a non-zero status. A faster configuration is possible. A single server can
+be used instead of four servers, the number of measurements can be reduced with
+the `maxsamples` option, and a timeout can be specified with the `-t` option.
+The following command would take only up to about 1 second.
+
+----
+# chronyd -q -t 1 'server pool.ntp.org iburst maxsamples 1'
+----
+
+=== Can `chronyd` be configured to control the clock like `ntpd`?
+
+It is not possible to perfectly emulate `ntpd`, but there are some options that
+can configure `chronyd` to behave more like `ntpd`.
+
+In the following example the `minsamples` directive slows down the response to
+changes in the frequency and offset of the clock. The `maxslewrate` and
+`corrtimeratio` directives reduce the maximum frequency error due to an offset
+correction and the `maxdrift` directive reduces the maximum assumed frequency
+error of the clock. The `makestep` directive enables a step threshold and the
+`maxchange` directive enables a panic threshold. The `maxclockerror` directive
+increases the minimum dispersion rate.
+
+----
+minsamples 32
+maxslewrate 500
+corrtimeratio 100
+maxdrift 500
+makestep 0.128 -1
+maxchange 1000 1 1
+maxclockerror 15
+----
+
+Note that increasing `minsamples` may cause the offsets in the `tracking` and
+`sourcestats` reports/logs to be significantly smaller than the actual offsets
+and be unsuitable for monitoring.
+
+=== What happened to the `commandkey` and `generatecommandkey` directives?
+
+They were removed in version 2.2. Authentication is no longer supported in the
+command protocol. Commands that required authentication are now allowed only
+through a Unix domain socket, which is accessible only by the root and _chrony_
+users. If you need to configure `chronyd` remotely or locally without the root
+password, please consider using ssh and/or sudo to run `chronyc` under the root
+or _chrony_ user on the host where `chronyd` is running.
 
 == Computer is not synchronising
 
-This is the most common problem.  There are a number of reasons, see the
+This is the most common problem. There are a number of reasons, see the
 following questions.
 
 === Behind a firewall?
 
-If there is a firewall between you and the NTP server you're trying to use, the
-packets may be blocked.  Try using a tool like +wireshark+ or +tcpdump+ to see if
-you're getting responses from the server.  If you have an external modem, see
-if the receive light blinks straight after the transmit light (when the link is
-quiet apart from the NTP traffic.)  Try adding +log measurements+ to the
-'chrony.conf' file and look in the 'measurements.log' file after +chronyd+ has
-been running for a short period. See if any measurements appear.
+Check the `Reach` value printed by the ``chronyc``'s `sources` command. If it's
+zero, it means `chronyd` did not get any valid responses from the NTP server
+you are trying to use. If there is a firewall between you and the server, the
+packets may be blocked. Try using a tool like `wireshark` or `tcpdump` to see
+if you're getting any responses from the server.
 
-=== Are NTP servers specified with the +offline+ option?
+When `chronyd` is receiving responses from the servers, the output of the
+`sources` command issued few minutes after `chronyd` start might look like
+this:
 
-Check that you're using +chronyc+\'s +online+ and +offline+ commands
-appropriately.  Again, check in 'measurements.log' to see if you're getting any
-data back from the server.
+----
+210 Number of sources = 3
+MS Name/IP address         Stratum Poll Reach LastRx Last sample
+===============================================================================
+^* foo.example.net               2   6   377    34   +484us[ -157us] +/-   30ms
+^- bar.example.net               2   6   377    34    +33ms[  +32ms] +/-   47ms
+^+ baz.example.net               3   6   377    35  -1397us[-2033us] +/-   60ms
+----
 
-=== Is +chronyd+ allowed to step the system clock?
+=== Are NTP servers specified with the `offline` option?
 
-By default, +chronyd+ adjusts the clock gradually by slowing it down or
-speeding it up.  If the clock is too far from the correct time, it will take
-a long time to correct the error.  The +System time+ value printed by the
-+chronyc+'s +tracking+ command is the remaining correction that needs to be
+Check that you're using ``chronyc``'s `online` and `offline` commands
+appropriately. The `activity` command prints the number of sources that are
+currently online and offline. For example:
+
+----
+200 OK
+3 sources online
+0 sources offline
+0 sources doing burst (return to online)
+0 sources doing burst (return to offline)
+0 sources with unknown address
+----
+
+=== Is `chronyd` allowed to step the system clock?
+
+By default, `chronyd` adjusts the clock gradually by slowing it down or
+speeding it up. If the clock is too far from the true time, it will take
+a long time to correct the error. The `System time` value printed by the
+``chronyc``'s `tracking` command is the remaining correction that needs to be
 applied to the system clock.
 
-The +makestep+ directive can be used to allow +chronyd+ to step the clock. For
-example, if 'chrony.conf' had
+The `makestep` directive can be used to allow `chronyd` to step the clock. For
+example, if _chrony.conf_ had
 
 ----
 makestep 1 3
 ----
 
 the clock would be stepped in the first three updates if its offset was larger
-than one second.  Normally, it's recommended to allow the step only in the
-first few updates, but in some cases (e.g. a computer without RTC or virtual
-machine which can be suspended and resumed with incorrect time) it may be
-necessary to allow the step at any clock update.  The example above would
-change to
+than one second. Normally, it's recommended to allow the step only in the first
+few updates, but in some cases (e.g. a computer without an RTC or virtual
+machine which can be suspended and resumed with an incorrect time) it may be
+necessary to allow the step on any clock update. The example above would change
+to
 
 ----
 makestep 1 -1
 ----
 
-== Issues with +chronyc+
+=== Using a Windows NTP server?
 
-=== I keep getting the error +506 Cannot talk to daemon+
+A common issue with Windows NTP servers is that they report a very large root
+dispersion (e.g. three seconds or more), which causes `chronyd` to ignore the
+server for being too inaccurate. The `sources` command may show a valid
+measurement, but the server is not selected for synchronisation. You can check
+the root dispersion of the server with the ``chronyc``'s `ntpdata` command.
 
-When accessing +chronyd+ remotely, make sure that the 'chrony.conf' file (on
-the computer where +chronyd+ is running) has a 'cmdallow' entry for the
-computer you are running +chronyc+ on and an appropriate 'bindcmdaddress'
-directive.  This isn't necessary for localhost.
+The `maxdistance` value needs to be increased in _chrony.conf_ to enable
+synchronisation to such a server. For example:
 
-Perhaps +chronyd+ is not running.  Try using the +ps+ command (e.g.  on Linux,
-+ps -auxw+) to see if it's running.  Or try +netstat -a+ and see if the ports
-123/udp and 323/udp are listening.  If +chronyd+ is not running, you may have a
-problem with the way you are trying to start it (e.g.  at boot time).
+----
+maxdistance 16.0
+----
+
+=== Using a PPS reference clock?
+
+A pulse-per-second (PPS) reference clock requires a non-PPS time source to
+determine which second of UTC corresponds to each pulse. If it is another
+reference clock specified with the `lock` option in the `refclock` directive,
+the offset between the two reference clocks must be smaller than 0.2 seconds in
+order for the PPS reference clock to work. With NMEA reference clocks it is
+common to have a larger offset. It needs to be corrected with the `offset`
+option.
+
+One approach to find out a good value of the `offset` option is to configure
+the reference clocks with the `noselect` option and compare them to an NTP
+server. For example, if the `sourcestats` command showed
+
+----
+Name/IP Address            NP  NR  Span  Frequency  Freq Skew  Offset  Std Dev
+==============================================================================
+PPS0                        0   0     0     +0.000   2000.000     +0ns  4000ms
+NMEA                       58  30   231    -96.494     38.406   +504ms  6080us
+foo.example.net             7   3   200     -2.991     16.141   -107us   492us
+----
+
+the offset of the NMEA source would need to be increased by about 0.504
+seconds. It does not have to be very accurate. As long as the offset of the
+NMEA reference clock stays below 0.2 seconds, the PPS reference clock should be
+able to determine the seconds corresponding to the pulses and allow the samples
+to be used for synchronisation.
+
+== Issues with `chronyc`
+
+=== I keep getting the error `506 Cannot talk to daemon`
+
+When accessing `chronyd` remotely, make sure that the _chrony.conf_ file (on
+the computer where `chronyd` is running) has a `cmdallow` entry for the
+computer you are running `chronyc` on and an appropriate `bindcmdaddress`
+directive. This isn't necessary for localhost.
+
+Perhaps `chronyd` is not running. Try using the `ps` command (e.g. on Linux,
+`ps -auxw`) to see if it's running. Or try `netstat -a` and see if the ports
+123/udp and 323/udp are listening. If `chronyd` is not running, you may have a
+problem with the way you are trying to start it (e.g. at boot time).
 
 Perhaps you have a firewall set up in a way that blocks packets on port
-323/udp.  You need to amend the firewall configuration in this case.
+323/udp. You need to amend the firewall configuration in this case.
 
-=== I keep getting the error +501 Not authorised+
+=== I keep getting the error `501 Not authorised`
 
-Since version 2.2, the +password+ command doesn't do anything and +chronyc+
-needs to run under the root or chrony user, which are allowed to access the
-Unix domain command socket.
+Since version 2.2, the `password` command doesn't do anything and `chronyc`
+needs to run locally under the root or _chrony_ user, which are allowed to
+access the ``chronyd``'s Unix domain command socket.
 
-=== Is the +chronyc+ / +chronyd+ protocol documented anywhere?
+With older versions, you need to authenticate with the `password` command first
+or use the `-a` option to authenticate automatically on start. The
+configuration file needs to specify a file which contains keys (`keyfile`
+directive) and which key in the key file should be used for `chronyc`
+authentication (`commandkey` directive).
 
-Only by the source code :-) See 'cmdmon.c' (+chronyd+ side) and 'client.c'
-(+chronyc+ side).
+=== Why does `chronyc tracking` always print an IPv4 address as reference ID?
+
+The reference ID is a 32-bit value and in versions before 3.0 it was printed in
+quad-dotted notation, even if the reference source did not actually have an
+IPv4 address. For IPv4 addresses, the reference ID is equal to the address, but
+for IPv6 addresses it is the first 32 bits of the MD5 sum of the address. For
+reference clocks, the reference ID is the value specified with the `refid`
+option in the `refclock` directive.
+
+Since version 3.0, the reference ID is printed as a hexadecimal number to avoid
+confusion with IPv4 addresses.
+
+If you need to get the IP address of the current reference source, use the `-n`
+option to disable resolving of IP addresses and read the second field (printed
+in parentheses) on the `Reference ID` line.
+
+=== Is the `chronyc` / `chronyd` protocol documented anywhere?
+
+Only by the source code. See _cmdmon.c_ (`chronyd` side) and _client.c_
+(`chronyc` side).
 
 == Real-time clock issues
 
 === What is the real-time clock (RTC)?
 
 This is the clock which keeps the time even when your computer is turned off.
-It is used to initialize the system clock on boot. It normally doesn't drift
+It is used to initialise the system clock on boot. It normally doesn't drift
 more than few seconds per day.
 
-There are two approaches how +chronyd+ can work with it.  One is to use the
-+rtcsync+ directive, which tells +chronyd+ to enable a kernel mode which sets
-the RTC from the system clock every 11 minutes.  +chronyd+ itself won't touch
-the RTC.  If the computer is not turned off for a long time, the RTC should
-still be close to the true time when the system clock will be initialized from
+There are two approaches how `chronyd` can work with it. One is to use the
+`rtcsync` directive, which tells `chronyd` to enable a kernel mode which sets
+the RTC from the system clock every 11 minutes. `chronyd` itself won't touch
+the RTC. If the computer is not turned off for a long time, the RTC should
+still be close to the true time when the system clock will be initialised from
 it on the next boot.
 
-The other option is to use the +rtcfile+ directive, which will tell +chronyd+
-to monitor the rate at which the RTC gains or loses time.  When +chronyd+ is
-started with the +-s+ option on the next boot, it will set the system time from
-the RTC and also compensate for the drift it has measured previously.  The
-+rtcautotrim+ directive can be used to keep the RTC close to the true time, but
+The other option is to use the `rtcfile` directive, which tells `chronyd` to
+monitor the rate at which the RTC gains or loses time. When `chronyd` is
+started with the `-s` option on the next boot, it will set the system time from
+the RTC and also compensate for the drift it has measured previously. The
+`rtcautotrim` directive can be used to keep the RTC close to the true time, but
 it's not strictly necessary if its only purpose is to set the system clock when
-+chronyd+ is started on boot.  See the documentation for details.
+`chronyd` is started on boot. See the documentation for details.
 
-=== I want to use +chronyd+'s RTC support. Must I disable +hwclock+?
+=== I want to use ``chronyd``'s RTC support. Must I disable `hwclock`?
 
-The +hwclock+ program is often set-up by default in the boot and shutdown
-scripts with many Linux installations.  With the kernel RTC synchronisation
-(+rtcsync+ directive), the RTC will be set also every 11 minutes as long as the
-system clock is synchronised.  If you want to use +chronyd+'s RTC monitoring
-(+rtcfile+ directive), it's important to disable +hwclock+ in the shutdown
-procedure.  If you don't, it will over-write the RTC with a new value, unknown
-to +chronyd+.  At the next reboot, +chronyd+ started with the +-s+ option will
+The `hwclock` program is often set-up by default in the boot and shutdown
+scripts with many Linux installations. With the kernel RTC synchronisation
+(`rtcsync` directive), the RTC will be set also every 11 minutes as long as the
+system clock is synchronised. If you want to use ``chronyd``'s RTC monitoring
+(`rtcfile` directive), it's important to disable `hwclock` in the shutdown
+procedure. If you don't, it will over-write the RTC with a new value, unknown
+to `chronyd`. At the next reboot, `chronyd` started with the `-s` option will
 compensate this (wrong) time with its estimate of how far the RTC has drifted
 whilst the power was off, giving a meaningless initial system time.
 
-There is no need to remove +hwclock+ from the boot process, as long as +chronyd+
+There is no need to remove `hwclock` from the boot process, as long as `chronyd`
 is started after it has run.
 
-=== I just keep getting the +513 RTC driver not running+ message
+=== I just keep getting the `513 RTC driver not running` message
 
-For the real time clock support to work, you need the following three
+For the real-time clock support to work, you need the following three
 things
 
-* a kernel that is supported (e.g. 2.2 onwards)
-* enhanced RTC support compiled into the kernel
-* an +rtcfile+ directive in your 'chrony.conf' file
+* an RTC in your computer
+* a Linux kernel with enabled RTC support
+* an `rtcfile` directive in your _chrony.conf_ file
 
-== NTP-specific issues
-
-=== Can +chronyd+ be driven from broadcast NTP servers?
-
-No, the broadcast client mode is not supported and there is currently no plan
-to implement it.  The broadcast and multicast modes are inherently less
-accurate and less secure (even with authentication) than the ordinary
-server/client mode and they are not as useful as they used to be.  Even with
-very modest hardware a single NTP server can serve time to hundreds of
-thousands of clients using the ordinary mode.
-
-=== Can +chronyd+ transmit broadcast NTP packets?
-
-Yes, the +broadcast+ directive can be used to enable the broadcast server mode
-to serve time to clients in the network which support the broadcast client mode
-(it's not supported in +chronyd+, see the previous question).
-
-=== Can +chronyd+ keep the system clock a fixed offset away from real time?
-
-This is not possible as the program currently stands.
-
-=== What happens if the network connection is dropped without using +chronyc+'s +offline+ command first?
-
-+chronyd+ will keep trying to access the server(s) that it thinks are online.
-When the network is connected again, it will take some time (on average half of
-the current polling interval) before new measurements are made and the clock is
-corrected. If the servers were set to offline and the +online+ command was
-issued when the network was connected, +chronyd+ would make new measurements
-immediately.
-
-The +auto_offline+ option to the +server+ entry in the 'chrony.conf' file may
-be useful to switch the servers to the offline state automatically.
-
-== Linux-specific issues
-
-=== I get +Could not open /dev/rtc, Device or resource busy+ in my syslog file
+=== I get `Could not open /dev/rtc, Device or resource busy` in my syslog file
 
 Some other program running on the system may be using the device.
 
-== Microsoft Windows
+=== What if my computer does not have an RTC or backup battery?
 
-=== Does +chrony+ support Windows?
+In this case you can still use the `-s` option to set the system clock to the
+last modification time of the drift file, which should correspond to the system
+time when `chronyd` was previously stopped. The initial system time will be
+increasing across reboots and applications started after `chronyd` will not
+observe backward steps.
 
-No.  The +chronyc+ program (the command-line client used for configuring
-+chronyd+ while it is running) has been successfully built and run under
-Cygwin in the past.  +chronyd+ is not portable, because part of it is
-very system-dependent.  It needs adapting to work with Windows'
+== NTP-specific issues
+
+=== Can `chronyd` be driven from broadcast/multicast NTP servers?
+
+No, the broadcast/multicast client mode is not supported and there is currently
+no plan to implement it. While the mode may be useful to simplify configuration
+of clients in large networks, it is inherently less accurate and less secure
+(even with authentication) than the ordinary client/server mode.
+
+When configuring a large number of clients in a network, it is recommended to
+use the `pool` directive with a DNS name which resolves to addresses of
+multiple NTP servers. The clients will automatically replace the servers when
+they become unreachable, or otherwise unsuitable for synchronisation, with new
+servers from the pool.
+
+Even with very modest hardware, an NTP server can serve time to hundreds of
+thousands of clients using the ordinary client/server mode.
+
+=== Can `chronyd` transmit broadcast NTP packets?
+
+Yes, the `broadcast` directive can be used to enable the broadcast server mode
+to serve time to clients in the network which support the broadcast client mode
+(it's not supported in `chronyd`, see the previous question).
+
+=== Can `chronyd` keep the system clock a fixed offset away from real time?
+
+Yes. Starting from version 3.0, an offset can be specified by the `offset`
+option for all time sources in the _chrony.conf_ file.
+
+=== What happens if the network connection is dropped without using ``chronyc``'s `offline` command first?
+
+`chronyd` will keep trying to access the sources that it thinks are online, and
+it will take longer before new measurements are actually made and the clock is
+corrected when the network is connected again. If the sources were set to
+offline, `chronyd` would make new measurements immediately after issuing the
+`online` command.
+
+Unless the network connection lasts only few minutes (less than the maximum
+polling interval), the delay is usually not a problem, and it may be acceptable
+to keep all sources online all the time.
+
+== Operating systems
+
+=== Does `chrony` support Windows?
+
+No. The `chronyc` program (the command-line client used for configuring
+`chronyd` while it is running) has been successfully built and run under
+Cygwin in the past. `chronyd` is not portable, because part of it is
+very system-dependent. It needs adapting to work with Windows'
 equivalent of the adjtimex() call, and it needs to be made to work as a
 service.
 
 === Are there any plans to support Windows?
 
-We have no plans to do this.  Anyone is welcome to pick this work up and
+We have no plans to do this. Anyone is welcome to pick this work up and
 contribute it back to the project.

doc/installation.adoc

@@ -0,0 +1,237 @@
+// This file is part of chrony
+//
+// Copyright (C) Richard P. Curnow  1997-2003
+// Copyright (C) Miroslav Lichvar  2009-2016
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of version 2 of the GNU General Public License as
+// published by the Free Software Foundation.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+= Installation
+
+The software is distributed as source code which has to be compiled. The source
+code is supplied in the form of a gzipped tar file, which unpacks to a
+subdirectory identifying the name and version of the program.
+
+A C compiler (e.g. `gcc` or `clang`) and GNU Make are needed to build `chrony`.
+The following libraries with their development files, and programs, are needed
+to enable optional features:
+
+* pkg-config: detection of development libraries
+* Nettle, NSS, or LibTomCrypt: secure hash functions (`SECHASH`)
+* libcap: dropping root privileges on Linux (`DROPROOT`)
+* libseccomp: system call filter on Linux (`SCFILTER`)
+* GnuTLS and Nettle: Network Time Security (`NTS`)
+* Editline: line editing in `chronyc` (`READLINE`)
+* timepps.h header: PPS reference clock
+* Asciidoctor: documentation in HTML format
+* Bash: test suite
+
+The following programs are needed when building `chrony` from the git
+repository instead of a released tar file:
+
+* Asciidoctor: manual pages
+* Bison: parser for chronyc settime command
+
+After unpacking the source code, change directory into it, and type
+
+----
+./configure
+----
+
+This is a shell script that automatically determines the system type. There is
+an optional parameter `--prefix`, which indicates the directory tree where the
+software should be installed. For example,
+
+----
+./configure --prefix=/opt/free
+----
+
+will install the `chronyd` daemon into `/opt/free/sbin` and the `chronyc`
+control program into `/opt/free/bin`. The default value for the prefix is
+`/usr/local`.
+
+The `configure` script assumes you want to use `gcc` as your compiler. If you
+want to use a different compiler, you can configure this way:
+
+----
+CC=cc ./configure --prefix=/opt/free
+----
+
+for Bourne-family shells, or
+
+----
+setenv CC cc
+setenv CFLAGS -O
+./configure --prefix=/opt/free
+----
+
+for C-family shells.
+
+If the software cannot (yet) be built on your system, an error message will be
+shown. Otherwise, `Makefile` will be generated.
+
+On Linux, if development files for the libcap library are available, `chronyd`
+will be built with support for dropping root privileges. On other systems no
+extra library is needed. The default user which `chronyd` should run as can be
+specified with the `--with-user` option of the `configure` script.
+
+If development files for the POSIX threads library are available, `chronyd`
+will be built with support for asynchronous resolving of hostnames specified in
+the `server`, `peer`, and `pool` directives. This allows `chronyd` operating as
+a server to respond to client requests when resolving a hostname. If you don't
+want to enable the support, specify the `--disable-asyncdns` flag to
+`configure`.
+
+If development files for the https://www.lysator.liu.se/~nisse/nettle/[Nettle],
+https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS[NSS], or
+http://www.libtom.net/LibTomCrypt/[libtomcrypt] library are available,
+`chronyd` will be built with support for other cryptographic hash functions
+than MD5, which can be used for NTP authentication with a symmetric key. If you
+don't want to enable the support, specify the `--disable-sechash` flag to
+`configure`.
+
+If development files for the editline or readline library are available,
+`chronyc` will be built with line editing support. If you don't want this,
+specify the `--disable-readline` flag to `configure`.
+
+If a `timepps.h` header is available (e.g. from the
+http://linuxpps.org[LinuxPPS project]), `chronyd` will be built with PPS API
+reference clock driver. If the header is installed in a location that isn't
+normally searched by the compiler, you can add it to the searched locations by
+setting the `CPPFLAGS` variable to `-I/path/to/timepps`.
+
+The `--help` option can be specified to `configure` to print all options
+supported by the script.
+
+Now type
+
+----
+make
+----
+
+to build the programs.
+
+If you want to build the manual in HTML, type
+
+----
+make docs
+----
+
+Once the programs have been successfully compiled, they need to be installed in
+their target locations. This step normally needs to be performed by the
+superuser, and requires the following command to be entered.
+
+----
+make install
+----
+
+This will install the binaries and man pages.
+
+To install the HTML version of the manual, enter the command
+
+----
+make install-docs
+----
+
+Now that the software is successfully installed, the next step is to set up a
+configuration file. The default location of the file is _/etc/chrony.conf_.
+Several examples of configuration with comments are included in the examples
+directory. Suppose you want to use public NTP servers from the pool.ntp.org
+project as your time reference. A minimal useful configuration file could be
+
+----
+pool pool.ntp.org iburst
+makestep 1.0 3
+rtcsync
+----
+
+Then, `chronyd` can be run. For security reasons, it's recommended to create an
+unprivileged user for `chronyd` and specify it with the `-u` command-line
+option or the `user` directive in the configuration file, or set the default
+user with the `--with-user` configure option before building.
+
+== Support for system call filtering
+
+`chronyd` can be built with support for the Linux secure computing (seccomp)
+facility. This requires development files for the
+https://github.com/seccomp/libseccomp[libseccomp] library and the
+`--enable-scfilter` option specified to `configure`. The `-F` option of
+`chronyd` will enable a system call filter, which should significantly reduce
+the kernel attack surface and possibly prevent kernel exploits from `chronyd`
+if it is compromised.
+
+== Support for line editing libraries
+
+`chronyc` can be built with support for line editing, this allows you to use
+the cursor keys to replay and edit old commands. Two libraries are supported
+which provide such functionality, editline and GNU readline.
+
+Please note that readline since version 6.0 is licensed under GPLv3+ which is
+incompatible with chrony's license GPLv2. You should use editline instead if
+you don't want to use older readline versions.
+
+The `configure` script will automatically enable the line editing support if
+one of the supported libraries is available. If they are both available, the
+editline library will be used.
+
+If you don't want to use it (in which case `chronyc` will use a minimal command
+line interface), invoke `configure` like this:
+
+----
+./configure --disable-readline other-options...
+----
+
+If you have editline, readline or ncurses installed in locations that aren't
+normally searched by the compiler and linker, you need to use extra options:
+
+`--with-readline-includes=directory_name`::
+  This defines the name of the directory above the one where `readline.h` is.
+  `readline.h` is assumed to be in `editline` or `readline` subdirectory of the
+  named directory.
+
+`--with-readline-library=directory_name`::
+  This defines the directory containing the `libedit.a` or `libedit.so` file,
+  or `libreadline.a` or `libreadline.so` file.
+
+`--with-ncurses-library=directory_name`::
+  This defines the directory containing the `libncurses.a` or `libncurses.so`
+  file.
+
+== Extra options for package builders
+
+The `configure` and `make` procedures have some extra options that may be
+useful if you are building a distribution package for `chrony`.
+
+The `--mandir=DIR` option to `configure` specifies an installation directory
+for the man pages. This overrides the `man` subdirectory of the argument to the
+`--prefix` option.
+
+----
+./configure --prefix=/usr --mandir=/usr/share/man
+----
+
+to set both options together.
+
+The final option is the `DESTDIR` option to the `make` command. For example,
+you could use the commands
+
+----
+./configure --prefix=/usr --mandir=/usr/share/man
+make all docs
+make install DESTDIR=./tmp
+cd tmp
+tar cvf - . | gzip -9 > chrony.tar.gz
+----
+
+to build a package. When untarred within the root directory, this will install
+the files to the intended final locations.

examples/chrony-wait.service

@@ -1,5 +1,6 @@
 [Unit]
 Description=Wait for chrony to synchronize system clock
+Documentation=man:chronyc(1)
 After=chronyd.service
 Requires=chronyd.service
 Before=time-sync.target
@@ -9,7 +10,7 @@ Wants=time-sync.target
 Type=oneshot
 # Wait up to ~10 minutes for chronyd to synchronize and the remaining
 # clock correction to be less than 0.1 seconds
-ExecStart=/usr/bin/chronyc waitsync 600 0.1 0.0 1
+ExecStart=/usr/bin/chronyc -h 127.0.0.1,::1 waitsync 600 0.1 0.0 1
 RemainAfterExit=yes
 StandardOutput=null
 

examples/chrony.conf.example1

@@ -4,8 +4,8 @@ pool pool.ntp.org iburst
 # Record the rate at which the system clock gains/losses time.
 driftfile /var/lib/chrony/drift
 
-# In first three updates step the system clock instead of slew
-# if the adjustment is larger than 1 second.
+# Allow the system clock to be stepped in the first three updates
+# if its offset is larger than 1 second.
 makestep 1.0 3
 
 # Enable kernel synchronization of the real-time clock (RTC).

examples/chrony.conf.example2

@@ -5,27 +5,31 @@ pool pool.ntp.org iburst
 # Record the rate at which the system clock gains/losses time.
 driftfile /var/lib/chrony/drift
 
-# In first three updates step the system clock instead of slew
-# if the adjustment is larger than 1 second.
+# Allow the system clock to be stepped in the first three updates
+# if its offset is larger than 1 second.
 makestep 1.0 3
 
 # Enable kernel synchronization of the real-time clock (RTC).
 rtcsync
 
-# Allow NTP client access from local network.
-#allow 192.168/16
+# Enable hardware timestamping on all interfaces that support it.
+#hwtimestamp *
 
-# Serve time even if not synchronized to any NTP server.
+# Increase the minimum number of selectable sources required to adjust
+# the system clock.
+#minsources 2
+
+# Allow NTP client access from local network.
+#allow 192.168.0.0/16
+
+# Serve time even if not synchronized to a time source.
 #local stratum 10
 
 # Specify file containing keys for NTP authentication.
 #keyfile /etc/chrony.keys
 
-# Disable logging of client accesses.
-noclientlog
-
-# Send message to syslog when clock adjustment is larger than 0.5 seconds.
-logchange 0.5
+# Get TAI-UTC offset and leap seconds from the system tz database.
+#leapsectz right/UTC
 
 # Specify directory for log files.
 logdir /var/log/chrony

examples/chrony.conf.example3

@@ -5,22 +5,6 @@
 # want to enable.  The more obscure options are not included.  Refer
 # to the documentation for these.
 #
-# Copyright 2002 Richard P. Curnow
-#
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of version 2 of the GNU General Public License as
-# published by the Free Software Foundation.
-# 
-# This program is distributed in the hope that it will be useful, but
-# WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-# General Public License for more details.
-# 
-# You should have received a copy of the GNU General Public License along
-# with this program; if not, write to the Free Software Foundation, Inc.,
-# 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
-# 
-#
 #######################################################################
 ### COMMENTS
 # Any of the following lines are comments (you have a choice of
@@ -49,42 +33,30 @@
 
 ! pool pool.ntp.org iburst
  
-# However, for dial-up use you probably want these instead.  The word
-# 'offline' means that the server is not visible at boot time.  Use
-# chronyc's 'online' command to tell chronyd that these servers have
-# become visible after you go on-line.
-
-! server foo.example.net offline
-! server bar.example.net offline
-! server baz.example.net offline
-
-! pool pool.ntp.org offline
-
-# You may want to specify NTP 'peers' instead.  If you run a network
-# with a lot of computers and want several computers running chrony to
-# have the 'front-line' interface to the public NTP servers, you can
-# 'peer' these machines together to increase robustness.
-
-! peer foo.example.net
-
-# There are other options to the 'server' and 'peer' directives that you
-# might want to use.  For example, you can ignore measurements whose
-# round-trip-time is too large (indicating that the measurement is
-# probably useless, because you don't know which way the measurement
-# message got held up.)  Consult the full documentation for details.
-
 #######################################################################
 ### AVOIDING POTENTIALLY BOGUS CHANGES TO YOUR CLOCK
 #
 # To avoid changes being made to your computer's gain/loss compensation
 # when the measurement history is too erratic, you might want to enable
-# one of the following lines.  The first seems good for dial-up (or
-# other high-latency connections like slow leased lines), the second
-# seems OK for a LAN environment.
+# one of the following lines.  The first seems good with servers on the
+# Internet, the second seems OK for a LAN environment.
 
 ! maxupdateskew 100
 ! maxupdateskew 5
 
+# If you want to increase the minimum number of selectable sources
+# required to update the system clock in order to make the
+# synchronisation more reliable, uncomment (and edit) the following
+# line.
+
+! minsources 2
+
+# If your computer has a good stable clock (e.g. it is not a virtual
+# machine), you might also want to reduce the maximum assumed drift
+# (frequency error) of the clock (the value is specified in ppm).
+
+! maxdrift 100
+
 #######################################################################
 ### FILENAMES ETC
 # Chrony likes to keep information about your computer's clock in files.
@@ -123,7 +95,13 @@ driftfile /var/lib/chrony/drift
 # still running and bail out.  If you want to change the path to the PID
 # file, uncomment this line and edit it.  The default path is shown.
 
-! pidfile /var/run/chronyd.pid
+! pidfile /var/run/chrony/chronyd.pid
+
+# If the system timezone database is kept up to date and includes the
+# right/UTC timezone, chronyd can use it to determine the current
+# TAI-UTC offset and when will the next leap second occur.
+
+! leapsectz right/UTC
 
 #######################################################################
 ### INITIAL CLOCK CORRECTION
@@ -197,16 +175,22 @@ driftfile /var/lib/chrony/drift
 # machine accesses it.  The information can be accessed by the 'clients'
 # command of chronyc.  You can disable this facility by uncommenting the
 # following line.  This will save a bit of memory if you have many
-# clients.
+# clients and it will also disable support for the interleaved mode.
 
 ! noclientlog
 
 # The clientlog size is limited to 512KB by default.  If you have many
-# clients, especially in many different subnets, you might want to
-# increase the limit. 
+# clients, you might want to increase the limit.
 
 ! clientloglimit 4194304
 
+# By default, chronyd tries to respond to all valid NTP requests from
+# allowed addresses.  If you want to limit the response rate for NTP
+# clients that are sending requests too frequently, uncomment and edit
+# the following line.
+
+! ratelimit interval 3 burst 8
+
 #######################################################################
 ### REPORTING BIG CLOCK CHANGES
 # Perhaps you want to know if chronyd suddenly detects any large error
@@ -233,6 +217,7 @@ driftfile /var/lib/chrony/drift
 
 # By default chronyd binds to the loopback interface.  Uncomment the
 # following lines to allow receiving command packets from remote hosts.
+
 ! bindcmdaddress 0.0.0.0
 ! bindcmdaddress ::
 
@@ -248,6 +233,21 @@ driftfile /var/lib/chrony/drift
 # syntax and meaning is the same as for 'allow' and 'deny', except that
 # 'cmdallow' and 'cmddeny' control access to the chronyd's command port.
 
+# Rate limiting can be enabled also for command packets.  (Note,
+# commands from localhost are never limited.)
+
+! cmdratelimit interval -4 burst 16
+
+#######################################################################
+### HARDWARE TIMESTAMPING
+# On Linux, if the network interface controller and its driver support
+# hardware timestamping, it can significantly improve the accuracy of
+# synchronisation. It can be enabled on specified interfaces only, or it
+# can be enabled on all interfaces that support it.
+
+! hwtimestamp eth0
+! hwtimestamp *
+
 #######################################################################
 ### REAL TIME CLOCK
 # chronyd can characterise the system's real-time clock.  This is the
@@ -277,6 +277,12 @@ driftfile /var/lib/chrony/drift
 
 ! rtcdevice /dev/misc/rtc
 
+# Alternatively, if not using the -s option, this directive can be used
+# to enable a mode in which the RTC is periodically set to the system
+# time, with no tracking of its drift.
+
+! rtcsync
+
 #######################################################################
 ### REAL TIME SCHEDULER
 # This directive tells chronyd to use the real-time FIFO scheduler with the

examples/chrony.keys.example

@@ -1,15 +1,13 @@
-# This is an example chrony keys file.  It is used for NTP authentication with
-# symmetric keys.  It should be readable only by root or the user to which
-# chronyd is configured to switch to.
+# This is an example chrony keys file.  It enables authentication of NTP
+# packets with symmetric keys when its location is specified by the keyfile
+# directive in chrony.conf(5).  It should be readable only by root and the
+# user under which chronyd is running.
 #
-# Don't use the example keys!  The keys need to be random for maximum security.
-# These shell commands can be used to generate random MD5 and SHA1 keys on
-# systems which have the /dev/urandom device:
-# echo "1 MD5 HEX:$(tr -d -c '[:xdigit:]' < /dev/urandom | head -c 32)"
-# echo "1 SHA1 HEX:$(tr -d -c '[:xdigit:]' < /dev/urandom | head -c 40)"
+# Don't use the example keys!  It's recommended to generate random keys using
+# the chronyc keygen command.
 
 # Examples of valid keys:
 
-#1 ALongAndRandomPassword
-#2 MD5 HEX:B028F91EA5C38D06C2E140B26C7F41EC
-#3 SHA1 HEX:1DC764E0791B11FA67EFC7ECBC4B0D73F68A070C
+#1 MD5 AVeryLongAndRandomPassword
+#2 MD5 HEX:12114855C7931009B4049EF3EFC48A139C3F989F
+#3 SHA1 HEX:B2159C05D6A219673A3B7E896B6DE07F6A440995

examples/chrony.nm-dispatcher

@@ -1,17 +1,15 @@
 #!/bin/sh
-# This is a NetworkManager dispatcher script for chronyd to set its NTP sources
-# online/offline when a default route is configured/removed on the system.
+# This is a NetworkManager dispatcher / networkd-dispatcher script for
+# chronyd to set its NTP sources online or offline when a network interface
+# is configured or removed
 
 export LC_ALL=C
 
-if [ "$2" = "up" ]; then
-	/sbin/ip route list dev "$1" | grep -q '^default' &&
-		/usr/bin/chronyc online > /dev/null 2>&1
-fi
+# For NetworkManager consider only up/down events
+[ $# -ge 2 ] && [ "$2" != "up" ] && [ "$2" != "down" ] && exit 0
 
-if [ "$2" = "down" ]; then
-	/sbin/ip route list | grep -q '^default' ||
-		/usr/bin/chronyc offline > /dev/null 2>&1
-fi
+# Note: for networkd-dispatcher routable.d ~= on and off.d ~= off
+
+chronyc onoffline > /dev/null 2>&1
 
 exit 0

examples/chrony.spec

@@ -1,56 +0,0 @@
-%global chrony_version @@VERSION@@
-%if 0%(echo %{chrony_version} | grep -q pre && echo 1)
-%global prerelease %(echo %{chrony_version} | sed 's/.*-//')
-%endif
-Summary: An NTP client/server
-Name: chrony
-Version: %(echo %{chrony_version} | sed 's/-.*//')
-Release: %{!?prerelease:1}%{?prerelease:0.1.%{prerelease}}
-Source: chrony-%{version}%{?prerelease:-%{prerelease}}.tar.gz
-License: GPLv2
-Group: Applications/Utilities
-BuildRoot: %{_tmppath}/%{name}-%{version}-root-%(id -u -n)
-Requires: info
-
-%description
-chrony is a client and server for the Network Time Protocol (NTP).
-This program keeps your computer's clock accurate. It was specially
-designed to support systems with intermittent Internet connections,
-but it also works well in permanently connected environments. It can
-also use hardware reference clocks, the system real-time clock, or
-manual input as time references.
-
-%prep
-%setup -q -n %{name}-%{version}%{?prerelease:-%{prerelease}}
-
-%build
-./configure \
-	--prefix=%{_prefix} \
-	--bindir=%{_bindir} \
-	--sbindir=%{_sbindir} \
-	--infodir=%{_infodir} \
-	--mandir=%{_mandir}
-make
-make chrony.txt
-make chrony.info
-
-%install
-rm -rf $RPM_BUILD_ROOT
-make install DESTDIR=$RPM_BUILD_ROOT
-rm -rf $RPM_BUILD_ROOT%{_docdir}
-mkdir -p $RPM_BUILD_ROOT%{_infodir}
-cp chrony.info* $RPM_BUILD_ROOT%{_infodir}
-
-%files
-%{_sbindir}/chronyd
-%{_bindir}/chronyc
-%{_infodir}/chrony.info*
-%{_mandir}/man1/chronyc.1.gz
-%{_mandir}/man5/chrony.conf.5.gz
-%{_mandir}/man8/chronyd.8.gz
-%doc README
-%doc chrony.txt
-%doc COPYING
-%doc examples/chrony.conf.example*
-%doc examples/chrony.keys.example
-

examples/chronyd.service

@@ -1,13 +1,18 @@
 [Unit]
 Description=NTP client/server
+Documentation=man:chronyd(8) man:chrony.conf(5)
 After=ntpdate.service sntp.service ntpd.service
 Conflicts=ntpd.service systemd-timesyncd.service
+ConditionCapability=CAP_SYS_TIME
 
 [Service]
 Type=forking
-PIDFile=/var/run/chronyd.pid
+PIDFile=/run/chrony/chronyd.pid
 EnvironmentFile=-/etc/sysconfig/chronyd
 ExecStart=/usr/sbin/chronyd $OPTIONS
+PrivateTmp=yes
+ProtectHome=yes
+ProtectSystem=full
 
 [Install]
 WantedBy=multi-user.target

hash_intmd5.c

@@ -29,6 +29,7 @@
 #include "sysincl.h"
 #include "hash.h"
 #include "memory.h"
+#include "util.h"
 
 #include "md5.c"
 
@@ -49,18 +50,17 @@ HSH_Hash(int id, const unsigned char *in1, unsigned int in1_len,
     const unsigned char *in2, unsigned int in2_len,
     unsigned char *out, unsigned int out_len)
 {
-  if (out_len < 16)
-    return 0;
-
   MD5Init(&ctx);
   MD5Update(&ctx, in1, in1_len);
   if (in2)
     MD5Update(&ctx, in2, in2_len);
   MD5Final(&ctx);
 
-  memcpy(out, ctx.digest, 16);
+  out_len = MIN(out_len, 16);
 
-  return 16;
+  memcpy(out, ctx.digest, out_len);
+
+  return out_len;
 }
 
 void

hash_nettle.c

@@ -0,0 +1,119 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2018
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Routines implementing crypto hashing using the nettle library.
+
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include <nettle/nettle-meta.h>
+
+#include "hash.h"
+#include "memory.h"
+
+struct hash {
+  const char *name;
+  const char *int_name;
+  const struct nettle_hash *nettle_hash;
+  void *context;
+};
+
+static struct hash hashes[] = {
+  { "MD5", "md5", NULL, NULL },
+  { "SHA1", "sha1", NULL, NULL },
+  { "SHA256", "sha256", NULL, NULL },
+  { "SHA384", "sha384", NULL, NULL },
+  { "SHA512", "sha512", NULL, NULL },
+  { "SHA3-224", "sha3_224", NULL, NULL },
+  { "SHA3-256", "sha3_256", NULL, NULL },
+  { "SHA3-384", "sha3_384", NULL, NULL },
+  { "SHA3-512", "sha3_512", NULL, NULL },
+  { NULL, NULL, NULL, NULL }
+};
+
+int
+HSH_GetHashId(const char *name)
+{
+  int id, nid;
+
+  for (id = 0; hashes[id].name; id++) {
+    if (!strcmp(name, hashes[id].name))
+      break;
+  }
+
+  if (!hashes[id].name)
+    return -1;
+
+  if (hashes[id].context)
+    return id;
+
+  for (nid = 0; nettle_hashes[nid]; nid++) {
+    if (!strcmp(hashes[id].int_name, nettle_hashes[nid]->name))
+      break;
+  }
+
+  if (!nettle_hashes[nid] || !nettle_hashes[nid]->context_size || !nettle_hashes[nid]->init)
+    return -1;
+
+  hashes[id].nettle_hash = nettle_hashes[nid];
+  hashes[id].context = Malloc(hashes[id].nettle_hash->context_size);
+
+  return id;
+}
+
+unsigned int
+HSH_Hash(int id, const unsigned char *in1, unsigned int in1_len,
+         const unsigned char *in2, unsigned int in2_len,
+         unsigned char *out, unsigned int out_len)
+{
+  const struct nettle_hash *hash;
+  void *context;
+
+  hash = hashes[id].nettle_hash;
+  context = hashes[id].context;
+
+  if (out_len > hash->digest_size)
+    out_len = hash->digest_size;
+
+  hash->init(context);
+  hash->update(context, in1_len, in1);
+  if (in2)
+    hash->update(context, in2_len, in2);
+  hash->digest(context, out_len, out);
+
+  return out_len;
+}
+
+void
+HSH_Finalise(void)
+{
+  int i;
+
+  for (i = 0; hashes[i].name; i++) {
+    if (hashes[i].context)
+      Free(hashes[i].context);
+  }
+}

hash_nss.c

@@ -32,6 +32,7 @@
 #include <nsslowhash.h>
 
 #include "hash.h"
+#include "util.h"
 
 static NSSLOWInitContext *ictx;
 
@@ -78,13 +79,17 @@ HSH_Hash(int id, const unsigned char *in1, unsigned int in1_len,
     const unsigned char *in2, unsigned int in2_len,
     unsigned char *out, unsigned int out_len)
 {
-  unsigned int ret;
+  unsigned char buf[MAX_HASH_LENGTH];
+  unsigned int ret = 0;
 
   NSSLOWHASH_Begin(hashes[id].context);
   NSSLOWHASH_Update(hashes[id].context, in1, in1_len);
   if (in2)
     NSSLOWHASH_Update(hashes[id].context, in2, in2_len);
-  NSSLOWHASH_End(hashes[id].context, out, &ret, out_len);
+  NSSLOWHASH_End(hashes[id].context, buf, &ret, sizeof (buf));
+
+  ret = MIN(ret, out_len);
+  memcpy(out, buf, ret);
 
   return ret;
 }

hash_tomcrypt.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2012
+ * Copyright (C) Miroslav Lichvar  2012, 2018
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -29,6 +29,7 @@
 
 #include "config.h"
 #include "hash.h"
+#include "util.h"
 
 struct hash {
   const char *name;
@@ -38,18 +39,6 @@ struct hash {
 
 static const struct hash hashes[] = {
   { "MD5", "md5", &md5_desc },
-#ifdef LTC_RIPEMD128
-  { "RMD128", "rmd128", &rmd128_desc },
-#endif
-#ifdef LTC_RIPEMD160
-  { "RMD160", "rmd160", &rmd160_desc },
-#endif
-#ifdef LTC_RIPEMD256
-  { "RMD256", "rmd256", &rmd256_desc },
-#endif
-#ifdef LTC_RIPEMD320
-  { "RMD320", "rmd320", &rmd320_desc },
-#endif
 #ifdef LTC_SHA1
   { "SHA1", "sha1", &sha1_desc },
 #endif
@@ -62,6 +51,12 @@ static const struct hash hashes[] = {
 #ifdef LTC_SHA512
   { "SHA512", "sha512", &sha512_desc },
 #endif
+#ifdef LTC_SHA3
+  { "SHA3-224", "sha3-224", &sha3_224_desc },
+  { "SHA3-256", "sha3-256", &sha3_256_desc },
+  { "SHA3-384", "sha3-384", &sha3_384_desc },
+  { "SHA3-512", "sha3-512", &sha3_512_desc },
+#endif
 #ifdef LTC_TIGER
   { "TIGER", "tiger", &tiger_desc },
 #endif
@@ -99,19 +94,24 @@ HSH_Hash(int id, const unsigned char *in1, unsigned int in1_len,
     const unsigned char *in2, unsigned int in2_len,
     unsigned char *out, unsigned int out_len)
 {
+  unsigned char buf[MAX_HASH_LENGTH];
   unsigned long len;
   int r;
 
-  len = out_len;
+  len = sizeof (buf);
   if (in2)
-    r = hash_memory_multi(id, out, &len,
-        in1, (unsigned long)in1_len, in2, (unsigned long)in2_len, NULL, 0);
+    r = hash_memory_multi(id, buf, &len,
+                          in1, (unsigned long)in1_len,
+                          in2, (unsigned long)in2_len, NULL, 0);
   else
-    r = hash_memory(id, in1, in1_len, out, &len);
+    r = hash_memory(id, in1, in1_len, buf, &len);
 
   if (r != CRYPT_OK)
     return 0;
 
+  len = MIN(len, out_len);
+  memcpy(out, buf, len);
+
   return len;
 }
 

hwclock.c

@@ -0,0 +1,227 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2016-2018
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Tracking of hardware clocks (e.g. RTC, PHC)
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "array.h"
+#include "hwclock.h"
+#include "local.h"
+#include "logging.h"
+#include "memory.h"
+#include "regress.h"
+#include "util.h"
+
+/* Minimum and maximum number of samples per clock */
+#define MIN_SAMPLES 2
+#define MAX_SAMPLES 64
+
+/* Maximum acceptable frequency offset of the clock */
+#define MAX_FREQ_OFFSET (2.0 / 3.0)
+
+struct HCL_Instance_Record {
+  /* HW and local reference timestamp */
+  struct timespec hw_ref;
+  struct timespec local_ref;
+
+  /* Samples stored as intervals (uncorrected for frequency error)
+     relative to local_ref and hw_ref */
+  double *x_data;
+  double *y_data;
+
+  /* Minimum, maximum and current number of samples */
+  int min_samples;
+  int max_samples;
+  int n_samples;
+
+  /* Maximum error of the last sample */
+  double last_err;
+
+  /* Minimum interval between samples */
+  double min_separation;
+
+  /* Flag indicating the offset and frequency values are valid */
+  int valid_coefs;
+
+  /* Estimated offset and frequency of HW clock relative to local clock */
+  double offset;
+  double frequency;
+};
+
+/* ================================================== */
+
+static void
+handle_slew(struct timespec *raw, struct timespec *cooked, double dfreq,
+            double doffset, LCL_ChangeType change_type, void *anything)
+{
+  HCL_Instance clock;
+  double delta;
+
+  clock = anything;
+
+  if (clock->n_samples)
+    UTI_AdjustTimespec(&clock->local_ref, cooked, &clock->local_ref, &delta, dfreq, doffset);
+  if (clock->valid_coefs)
+    clock->frequency /= 1.0 - dfreq;
+}
+
+/* ================================================== */
+
+HCL_Instance
+HCL_CreateInstance(int min_samples, int max_samples, double min_separation)
+{
+  HCL_Instance clock;
+
+  min_samples = CLAMP(MIN_SAMPLES, min_samples, MAX_SAMPLES);
+  max_samples = CLAMP(MIN_SAMPLES, max_samples, MAX_SAMPLES);
+  max_samples = MAX(min_samples, max_samples);
+
+  clock = MallocNew(struct HCL_Instance_Record);
+  clock->x_data = MallocArray(double, max_samples);
+  clock->y_data = MallocArray(double, max_samples);
+  clock->x_data[max_samples - 1] = 0.0;
+  clock->y_data[max_samples - 1] = 0.0;
+  clock->min_samples = min_samples;
+  clock->max_samples = max_samples;
+  clock->n_samples = 0;
+  clock->valid_coefs = 0;
+  clock->min_separation = min_separation;
+
+  LCL_AddParameterChangeHandler(handle_slew, clock);
+
+  return clock;
+}
+
+/* ================================================== */
+
+void HCL_DestroyInstance(HCL_Instance clock)
+{
+  LCL_RemoveParameterChangeHandler(handle_slew, clock);
+  Free(clock->y_data);
+  Free(clock->x_data);
+  Free(clock);
+}
+
+/* ================================================== */
+
+int
+HCL_NeedsNewSample(HCL_Instance clock, struct timespec *now)
+{
+  if (!clock->n_samples ||
+      fabs(UTI_DiffTimespecsToDouble(now, &clock->local_ref)) >= clock->min_separation)
+    return 1;
+
+  return 0;
+}
+
+/* ================================================== */
+
+void
+HCL_AccumulateSample(HCL_Instance clock, struct timespec *hw_ts,
+                     struct timespec *local_ts, double err)
+{
+  double hw_delta, local_delta, local_freq, raw_freq;
+  int i, n_runs, best_start;
+
+  local_freq = 1.0 - LCL_ReadAbsoluteFrequency() / 1.0e6;
+
+  /* Shift old samples */
+  if (clock->n_samples) {
+    if (clock->n_samples >= clock->max_samples)
+      clock->n_samples--;
+
+    hw_delta = UTI_DiffTimespecsToDouble(hw_ts, &clock->hw_ref);
+    local_delta = UTI_DiffTimespecsToDouble(local_ts, &clock->local_ref) / local_freq;
+
+    if (hw_delta <= 0.0 || local_delta < clock->min_separation / 2.0) {
+      clock->n_samples = 0;
+      DEBUG_LOG("HW clock reset interval=%f", local_delta);
+    }
+
+    for (i = clock->max_samples - clock->n_samples; i < clock->max_samples; i++) {
+      clock->y_data[i - 1] = clock->y_data[i] - hw_delta;
+      clock->x_data[i - 1] = clock->x_data[i] - local_delta;
+    }
+  }
+
+  clock->n_samples++;
+  clock->hw_ref = *hw_ts;
+  clock->local_ref = *local_ts;
+  clock->last_err = err;
+
+  /* Get new coefficients */
+  clock->valid_coefs =
+    RGR_FindBestRobustRegression(clock->x_data + clock->max_samples - clock->n_samples,
+                                 clock->y_data + clock->max_samples - clock->n_samples,
+                                 clock->n_samples, 1.0e-10, &clock->offset, &raw_freq,
+                                 &n_runs, &best_start);
+
+  if (!clock->valid_coefs) {
+    DEBUG_LOG("HW clock needs more samples");
+    return;
+  }
+
+  clock->frequency = raw_freq / local_freq;
+
+  /* Drop unneeded samples */
+  if (clock->n_samples > clock->min_samples)
+    clock->n_samples -= MIN(best_start, clock->n_samples - clock->min_samples);
+
+  /* If the fit doesn't cross the error interval of the last sample,
+     or the frequency is not sane, drop all samples and start again */
+  if (fabs(clock->offset) > err ||
+      fabs(clock->frequency - 1.0) > MAX_FREQ_OFFSET) {
+    DEBUG_LOG("HW clock reset");
+    clock->n_samples = 0;
+    clock->valid_coefs = 0;
+  }
+
+  DEBUG_LOG("HW clock samples=%d offset=%e freq=%e raw_freq=%e err=%e ref_diff=%e",
+            clock->n_samples, clock->offset, clock->frequency - 1.0, raw_freq - 1.0, err,
+            UTI_DiffTimespecsToDouble(&clock->hw_ref, &clock->local_ref));
+}
+
+/* ================================================== */
+
+int
+HCL_CookTime(HCL_Instance clock, struct timespec *raw, struct timespec *cooked, double *err)
+{
+  double offset, elapsed;
+
+  if (!clock->valid_coefs)
+    return 0;
+
+  elapsed = UTI_DiffTimespecsToDouble(raw, &clock->hw_ref);
+  offset = elapsed / clock->frequency - clock->offset;
+  UTI_AddDoubleToTimespec(&clock->local_ref, offset, cooked);
+
+  /* Fow now, just return the error of the last sample */
+  if (err)
+    *err = clock->last_err;
+
+  return 1;
+}

hwclock.h

@@ -0,0 +1,49 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2016
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header for tracking of hardware clocks */
+
+#ifndef GOT_HWCLOCK_H
+#define GOT_HWCLOCK_H
+
+typedef struct HCL_Instance_Record *HCL_Instance;
+
+/* Create a new HW clock instance */
+extern HCL_Instance HCL_CreateInstance(int min_samples, int max_samples,
+                                       double min_separation);
+
+/* Destroy a HW clock instance */
+extern void HCL_DestroyInstance(HCL_Instance clock);
+
+/* Check if a new sample should be accumulated at this time */
+extern int HCL_NeedsNewSample(HCL_Instance clock, struct timespec *now);
+
+/* Accumulate a new sample */
+extern void HCL_AccumulateSample(HCL_Instance clock, struct timespec *hw_ts,
+                                 struct timespec *local_ts, double err);
+
+/* Convert raw hardware time to cooked local time */
+extern int HCL_CookTime(HCL_Instance clock, struct timespec *raw, struct timespec *cooked,
+                        double *err);
+
+#endif

keys.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2012-2014
+ * Copyright (C) Miroslav Lichvar  2012-2016
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -32,6 +32,7 @@
 
 #include "array.h"
 #include "keys.h"
+#include "cmac.h"
 #include "cmdparse.h"
 #include "conf.h"
 #include "memory.h"
@@ -39,12 +40,25 @@
 #include "local.h"
 #include "logging.h"
 
+/* Consider 80 bits as the absolute minimum for a secure key */
+#define MIN_SECURE_KEY_LENGTH 10
+
+typedef enum {
+  NTP_MAC,
+  CMAC,
+} KeyClass;
 
 typedef struct {
   uint32_t id;
-  char *val;
-  int len;
-  int hash_id;
+  KeyClass class;
+  union {
+    struct {
+      unsigned char *value;
+      int length;
+      int hash_id;
+    } ntp_mac;
+    CMC_Instance cmac;
+  } data;
   int auth_delay;
 } Key;
 
@@ -60,9 +74,21 @@ static void
 free_keys(void)
 {
   unsigned int i;
+  Key *key;
 
-  for (i = 0; i < ARR_GetSize(keys); i++)
-    Free(((Key *)ARR_GetElement(keys, i))->val);
+  for (i = 0; i < ARR_GetSize(keys); i++) {
+    key = ARR_GetElement(keys, i);
+    switch (key->class) {
+      case NTP_MAC:
+        Free(key->data.ntp_mac.value);
+        break;
+      case CMAC:
+        CMC_DestroyInstance(key->data.cmac);
+        break;
+      default:
+        assert(0);
+    }
+  }
 
   ARR_SetSize(keys, 0);
   cache_valid = 0;
@@ -101,29 +127,49 @@ static int
 determine_hash_delay(uint32_t key_id)
 {
   NTP_Packet pkt;
-  struct timeval before, after;
-  unsigned long usecs, min_usecs=0;
-  int i;
+  struct timespec before, after;
+  double diff, min_diff;
+  int i, nsecs;
+
+  memset(&pkt, 0, sizeof (pkt));
 
   for (i = 0; i < 10; i++) {
     LCL_ReadRawTime(&before);
-    KEY_GenerateAuth(key_id, (unsigned char *)&pkt, NTP_NORMAL_PACKET_LENGTH,
-        (unsigned char *)&pkt.auth_data, sizeof (pkt.auth_data));
+    KEY_GenerateAuth(key_id, (unsigned char *)&pkt, NTP_HEADER_LENGTH,
+                     (unsigned char *)&pkt + NTP_HEADER_LENGTH,
+                     sizeof (pkt) - NTP_HEADER_LENGTH);
     LCL_ReadRawTime(&after);
 
-    usecs = (after.tv_sec - before.tv_sec) * 1000000 + (after.tv_usec - before.tv_usec);
+    diff = UTI_DiffTimespecsToDouble(&after, &before);
 
-    if (i == 0 || usecs < min_usecs) {
-      min_usecs = usecs;
-    }
+    if (i == 0 || min_diff > diff)
+      min_diff = diff;
   }
 
-  /* Add on a bit extra to allow for copying, conversions etc */
-  min_usecs += min_usecs >> 4;
+  nsecs = 1.0e9 * min_diff;
 
-  DEBUG_LOG(LOGF_Keys, "authentication delay for key %"PRIu32": %ld useconds", key_id, min_usecs);
+  DEBUG_LOG("authentication delay for key %"PRIu32": %d nsecs", key_id, nsecs);
 
-  return min_usecs;
+  return nsecs;
+}
+
+/* ================================================== */
+/* Decode key encoded in ASCII or HEX */
+
+static int
+decode_key(char *key)
+{
+  int len = strlen(key);
+
+  if (!strncmp(key, "ASCII:", 6)) {
+    memmove(key, key + 6, len - 6);
+    return len - 6;
+  } else if (!strncmp(key, "HEX:", 4)) {
+    return UTI_HexToBytes(key + 4, key, len);
+  } else {
+    /* assume ASCII */
+    return len;
+  }
 }
 
 /* ================================================== */
@@ -151,11 +197,11 @@ compare_keys_by_id(const void *a, const void *b)
 void
 KEY_Reload(void)
 {
-  unsigned int i, line_number;
+  unsigned int i, line_number, key_length, cmac_key_length;
   FILE *in;
-  uint32_t key_id;
-  char line[2048], *keyval, *key_file;
-  const char *hashname;
+  char line[2048], *key_file, *key_value;
+  const char *key_type;
+  int hash_id;
   Key key;
 
   free_keys();
@@ -166,9 +212,9 @@ KEY_Reload(void)
   if (!key_file)
     return;
 
-  in = fopen(key_file, "r");
+  in = UTI_OpenFile(NULL, key_file, NULL, 'r', 0);
   if (!in) {
-    LOG(LOGS_WARN, LOGF_Keys, "Could not open keyfile %s", key_file);
+    LOG(LOGS_WARN, "Could not open keyfile %s", key_file);
     return;
   }
 
@@ -179,26 +225,43 @@ KEY_Reload(void)
     if (!*line)
       continue;
 
-    if (!CPS_ParseKey(line, &key_id, &hashname, &keyval)) {
-      LOG(LOGS_WARN, LOGF_Keys, "Could not parse key at line %d in file %s", line_number, key_file);
+    memset(&key, 0, sizeof (key));
+
+    if (!CPS_ParseKey(line, &key.id, &key_type, &key_value)) {
+      LOG(LOGS_WARN, "Could not parse key at line %u in file %s", line_number, key_file);
       continue;
     }
 
-    key.hash_id = HSH_GetHashId(hashname);
-    if (key.hash_id < 0) {
-      LOG(LOGS_WARN, LOGF_Keys, "Unknown hash function in key %"PRIu32, key_id);
+    key_length = decode_key(key_value);
+    if (key_length == 0) {
+      LOG(LOGS_WARN, "Could not decode key %"PRIu32, key.id);
       continue;
     }
 
-    key.len = UTI_DecodePasswordFromText(keyval);
-    if (!key.len) {
-      LOG(LOGS_WARN, LOGF_Keys, "Could not decode password in key %"PRIu32, key_id);
+    hash_id = HSH_GetHashId(key_type);
+    cmac_key_length = CMC_GetKeyLength(key_type);
+
+    if (hash_id >= 0) {
+      key.class = NTP_MAC;
+      key.data.ntp_mac.value = MallocArray(unsigned char, key_length);
+      memcpy(key.data.ntp_mac.value, key_value, key_length);
+      key.data.ntp_mac.length = key_length;
+      key.data.ntp_mac.hash_id = hash_id;
+    } else if (cmac_key_length > 0) {
+      if (cmac_key_length != key_length) {
+        LOG(LOGS_WARN, "Invalid length of %s key %"PRIu32" (expected %u bits)",
+            key_type, key.id, 8 * cmac_key_length);
+        continue;
+      }
+
+      key.class = CMAC;
+      key.data.cmac = CMC_CreateInstance(key_type, (unsigned char *)key_value, key_length);
+      assert(key.data.cmac);
+    } else {
+      LOG(LOGS_WARN, "Unknown hash function or cipher in key %"PRIu32, key.id);
       continue;
     }
 
-    key.id = key_id;
-    key.val = MallocArray(char, key.len);
-    memcpy(key.val, keyval, key.len);
     ARR_AppendElement(keys, &key);
   }
 
@@ -212,7 +275,7 @@ KEY_Reload(void)
   /* Check for duplicates */
   for (i = 1; i < ARR_GetSize(keys); i++) {
     if (get_key(i - 1)->id == get_key(i)->id)
-      LOG(LOGS_WARN, LOGF_Keys, "Detected duplicate key %"PRIu32, get_key(i - 1)->id);
+      LOG(LOGS_WARN, "Detected duplicate key %"PRIu32, get_key(i - 1)->id);
   }
 
   /* Erase any passwords from stack */
@@ -291,8 +354,31 @@ KEY_GetAuthDelay(uint32_t key_id)
 /* ================================================== */
 
 int
-KEY_GenerateAuth(uint32_t key_id, const unsigned char *data, int data_len,
-    unsigned char *auth, int auth_len)
+KEY_GetAuthLength(uint32_t key_id)
+{
+  unsigned char buf[MAX_HASH_LENGTH];
+  Key *key;
+
+  key = get_key_by_id(key_id);
+
+  if (!key)
+    return 0;
+
+  switch (key->class) {
+    case NTP_MAC:
+      return HSH_Hash(key->data.ntp_mac.hash_id, buf, 0, buf, 0, buf, sizeof (buf));
+    case CMAC:
+      return CMC_Hash(key->data.cmac, buf, 0, buf, sizeof (buf));
+    default:
+      assert(0);
+      return 0;
+  }
+}
+
+/* ================================================== */
+
+int
+KEY_CheckKeyLength(uint32_t key_id)
 {
   Key *key;
 
@@ -301,15 +387,66 @@ KEY_GenerateAuth(uint32_t key_id, const unsigned char *data, int data_len,
   if (!key)
     return 0;
 
-  return UTI_GenerateNTPAuth(key->hash_id, (unsigned char *)key->val,
-                             key->len, data, data_len, auth, auth_len);
+  switch (key->class) {
+    case NTP_MAC:
+      return key->data.ntp_mac.length >= MIN_SECURE_KEY_LENGTH;
+    default:
+      return 1;
+  }
+}
+
+/* ================================================== */
+
+static int
+generate_auth(Key *key, const unsigned char *data, int data_len,
+              unsigned char *auth, int auth_len)
+{
+  switch (key->class) {
+    case NTP_MAC:
+      return HSH_Hash(key->data.ntp_mac.hash_id, key->data.ntp_mac.value,
+                      key->data.ntp_mac.length, data, data_len, auth, auth_len);
+    case CMAC:
+      return CMC_Hash(key->data.cmac, data, data_len, auth, auth_len);
+    default:
+      return 0;
+  }
+}
+
+/* ================================================== */
+
+static int
+check_auth(Key *key, const unsigned char *data, int data_len,
+           const unsigned char *auth, int auth_len, int trunc_len)
+{
+  unsigned char buf[MAX_HASH_LENGTH];
+  int hash_len;
+
+  hash_len = generate_auth(key, data, data_len, buf, sizeof (buf));
+
+  return MIN(hash_len, trunc_len) == auth_len && !memcmp(buf, auth, auth_len);
+}
+
+/* ================================================== */
+
+int
+KEY_GenerateAuth(uint32_t key_id, const unsigned char *data, int data_len,
+                 unsigned char *auth, int auth_len)
+{
+  Key *key;
+
+  key = get_key_by_id(key_id);
+
+  if (!key)
+    return 0;
+
+  return generate_auth(key, data, data_len, auth, auth_len);
 }
 
 /* ================================================== */
 
 int
 KEY_CheckAuth(uint32_t key_id, const unsigned char *data, int data_len,
-    const unsigned char *auth, int auth_len)
+              const unsigned char *auth, int auth_len, int trunc_len)
 {
   Key *key;
 
@@ -318,6 +455,5 @@ KEY_CheckAuth(uint32_t key_id, const unsigned char *data, int data_len,
   if (!key)
     return 0;
 
-  return UTI_CheckNTPAuth(key->hash_id, (unsigned char *)key->val,
-                          key->len, data, data_len, auth, auth_len);
+  return check_auth(key, data, data_len, auth, auth_len, trunc_len);
 }

keys.h

@@ -37,10 +37,12 @@ extern void KEY_Reload(void);
 extern int KEY_GetKey(uint32_t key_id, char **key, int *len);
 extern int KEY_KeyKnown(uint32_t key_id);
 extern int KEY_GetAuthDelay(uint32_t key_id);
+extern int KEY_GetAuthLength(uint32_t key_id);
+extern int KEY_CheckKeyLength(uint32_t key_id);
 
 extern int KEY_GenerateAuth(uint32_t key_id, const unsigned char *data,
     int data_len, unsigned char *auth, int auth_len);
-extern int KEY_CheckAuth(uint32_t key_id, const unsigned char *data,
-    int data_len, const unsigned char *auth, int auth_len);
+extern int KEY_CheckAuth(uint32_t key_id, const unsigned char *data, int data_len,
+                         const unsigned char *auth, int auth_len, int trunc_len);
 
 #endif /* GOT_KEYS_H */

local.c

@@ -42,13 +42,12 @@
 
 /* ================================================== */
 
-/* Maximum allowed frequency offset in ppm, the time must not stop
-   or run backwards */
-#define MAX_FREQ 500000.0
-
 /* Variable to store the current frequency, in ppm */
 static double current_freq_ppm;
 
+/* Maximum allowed frequency, in ppm */
+static double max_freq_ppm;
+
 /* Temperature compensation, in ppm */
 static double temp_comp_ppm;
 
@@ -107,40 +106,47 @@ static double max_clock_error;
    under 1s of busy waiting. */
 #define NITERS 100
 
+#define NSEC_PER_SEC 1000000000
+
 static void
 calculate_sys_precision(void)
 {
-  struct timeval tv, old_tv;
-  int dusec, best_dusec;
-  int iters;
+  struct timespec ts, old_ts;
+  int iters, diff, best;
 
-  gettimeofday(&old_tv, NULL);
-  best_dusec = 1000000; /* Assume we must be better than a second */
+  LCL_ReadRawTime(&old_ts);
+
+  /* Assume we must be better than a second */
+  best = NSEC_PER_SEC;
   iters = 0;
+
   do {
-    gettimeofday(&tv, NULL);
-    dusec = 1000000*(tv.tv_sec - old_tv.tv_sec) + (tv.tv_usec - old_tv.tv_usec);
-    old_tv = tv;
-    if (dusec > 0)  {
-      if (dusec < best_dusec) {
-        best_dusec = dusec;
-      }
+    LCL_ReadRawTime(&ts);
+
+    diff = NSEC_PER_SEC * (ts.tv_sec - old_ts.tv_sec) + (ts.tv_nsec - old_ts.tv_nsec);
+
+    old_ts = ts;
+    if (diff > 0) {
+      if (diff < best)
+        best = diff;
       iters++;
     }
   } while (iters < NITERS);
 
-  assert(best_dusec > 0);
+  assert(best > 0);
 
-  precision_quantum = best_dusec * 1.0e-6;
+  precision_quantum = 1.0e-9 * best;
 
   /* Get rounded log2 value of the measured precision */
   precision_log = 0;
-  while (best_dusec < 707107) {
+  while (best < 707106781) {
     precision_log--;
-    best_dusec *= 2;
+    best *= 2;
   }
 
-  DEBUG_LOG(LOGF_Local, "Clock precision %.9f (%d)", precision_quantum, precision_log);
+  assert(precision_log >= -30);
+
+  DEBUG_LOG("Clock precision %.9f (%d)", precision_quantum, precision_log);
 }
 
 /* ================================================== */
@@ -166,6 +172,11 @@ LCL_Initialise(void)
 
   calculate_sys_precision();
 
+  /* This is the maximum allowed frequency offset in ppm, the time must
+     never stop or run backwards */
+  max_freq_ppm = CNF_GetMaxDrift();
+  max_freq_ppm = CLAMP(0.0, max_freq_ppm, 500000.0);
+
   max_clock_error = CNF_GetMaxClockError() * 1e-6;
 }
 
@@ -274,7 +285,7 @@ LCL_IsFirstParameterChangeHandler(LCL_ParameterChangeHandler handler)
 /* ================================================== */
 
 static void
-invoke_parameter_change_handlers(struct timeval *raw, struct timeval *cooked,
+invoke_parameter_change_handlers(struct timespec *raw, struct timespec *cooked,
                                  double dfreq, double doffset,
                                  LCL_ChangeType change_type)
 {
@@ -341,23 +352,29 @@ void LCL_RemoveDispersionNotifyHandler(LCL_DispersionNotifyHandler handler, void
 }
 
 /* ================================================== */
-/* At the moment, this is just gettimeofday(), because
-   I can't think of a Unix system where it would not be */
 
 void
-LCL_ReadRawTime(struct timeval *result)
+LCL_ReadRawTime(struct timespec *ts)
 {
-  if (gettimeofday(result, NULL) < 0) {
-    LOG_FATAL(LOGF_Local, "gettimeofday() failed");
-  }
+#if HAVE_CLOCK_GETTIME
+  if (clock_gettime(CLOCK_REALTIME, ts) < 0)
+    LOG_FATAL("clock_gettime() failed : %s", strerror(errno));
+#else
+  struct timeval tv;
+
+  if (gettimeofday(&tv, NULL) < 0)
+    LOG_FATAL("gettimeofday() failed : %s", strerror(errno));
+
+  UTI_TimevalToTimespec(&tv, ts);
+#endif
 }
 
 /* ================================================== */
 
 void
-LCL_ReadCookedTime(struct timeval *result, double *err)
+LCL_ReadCookedTime(struct timespec *result, double *err)
 {
-  struct timeval raw;
+  struct timespec raw;
 
   LCL_ReadRawTime(&raw);
   LCL_CookTime(&raw, result, err);
@@ -366,18 +383,18 @@ LCL_ReadCookedTime(struct timeval *result, double *err)
 /* ================================================== */
 
 void
-LCL_CookTime(struct timeval *raw, struct timeval *cooked, double *err)
+LCL_CookTime(struct timespec *raw, struct timespec *cooked, double *err)
 {
   double correction;
 
   LCL_GetOffsetCorrection(raw, &correction, err);
-  UTI_AddDoubleToTimeval(raw, correction, cooked);
+  UTI_AddDoubleToTimespec(raw, correction, cooked);
 }
 
 /* ================================================== */
 
 void
-LCL_GetOffsetCorrection(struct timeval *raw, double *correction, double *err)
+LCL_GetOffsetCorrection(struct timespec *raw, double *correction, double *err)
 {
   /* Call system specific driver to get correction */
   (*drv_offset_convert)(raw, correction, err);
@@ -406,24 +423,24 @@ LCL_ReadAbsoluteFrequency(void)
 static double
 clamp_freq(double freq)
 {
-  if (freq <= MAX_FREQ && freq >= -MAX_FREQ)
+  if (freq <= max_freq_ppm && freq >= -max_freq_ppm)
     return freq;
 
-  LOG(LOGS_WARN, LOGF_Local, "Frequency %.1f ppm exceeds allowed maximum", freq);
+  LOG(LOGS_WARN, "Frequency %.1f ppm exceeds allowed maximum", freq);
 
-  return freq >= MAX_FREQ ? MAX_FREQ : -MAX_FREQ;
+  return CLAMP(-max_freq_ppm, freq, max_freq_ppm);
 }
 
 /* ================================================== */
 
 static int
-check_offset(struct timeval *now, double offset)
+check_offset(struct timespec *now, double offset)
 {
   /* Check if the time will be still sane with accumulated offset */
   if (UTI_IsTimeOffsetSane(now, -offset))
       return 1;
 
-  LOG(LOGS_WARN, LOGF_Local, "Adjustment of %.1f seconds is invalid", -offset);
+  LOG(LOGS_WARN, "Adjustment of %.1f seconds is invalid", -offset);
   return 0;
 }
 
@@ -435,7 +452,7 @@ check_offset(struct timeval *now, double offset)
 void
 LCL_SetAbsoluteFrequency(double afreq_ppm)
 {
-  struct timeval raw, cooked;
+  struct timespec raw, cooked;
   double dfreq;
   
   afreq_ppm = clamp_freq(afreq_ppm);
@@ -466,7 +483,7 @@ LCL_SetAbsoluteFrequency(double afreq_ppm)
 void
 LCL_AccumulateDeltaFrequency(double dfreq)
 {
-  struct timeval raw, cooked;
+  struct timespec raw, cooked;
   double old_freq_ppm;
 
   old_freq_ppm = current_freq_ppm;
@@ -495,7 +512,7 @@ LCL_AccumulateDeltaFrequency(double dfreq)
 void
 LCL_AccumulateOffset(double offset, double corr_rate)
 {
-  struct timeval raw, cooked;
+  struct timespec raw, cooked;
 
   /* In this case, the cooked time to be passed to the notify clients
      has to be the cooked time BEFORE the change was made */
@@ -517,7 +534,7 @@ LCL_AccumulateOffset(double offset, double corr_rate)
 int
 LCL_ApplyStepOffset(double offset)
 {
-  struct timeval raw, cooked;
+  struct timespec raw, cooked;
 
   /* In this case, the cooked time to be passed to the notify clients
      has to be the cooked time BEFORE the change was made */
@@ -529,7 +546,7 @@ LCL_ApplyStepOffset(double offset)
       return 0;
 
   if (!(*drv_apply_step_offset)(offset)) {
-    LOG(LOGS_ERR, LOGF_Local, "Could not step clock");
+    LOG(LOGS_ERR, "Could not step system clock");
     return 0;
   }
 
@@ -545,7 +562,7 @@ LCL_ApplyStepOffset(double offset)
 /* ================================================== */
 
 void
-LCL_NotifyExternalTimeStep(struct timeval *raw, struct timeval *cooked,
+LCL_NotifyExternalTimeStep(struct timespec *raw, struct timespec *cooked,
     double offset, double dispersion)
 {
   /* Dispatch to all handlers */
@@ -559,7 +576,7 @@ LCL_NotifyExternalTimeStep(struct timeval *raw, struct timeval *cooked,
 void
 LCL_NotifyLeap(int leap)
 {
-  struct timeval raw, cooked;
+  struct timespec raw, cooked;
 
   LCL_ReadRawTime(&raw);
   LCL_CookTime(&raw, &cooked, NULL);
@@ -576,7 +593,7 @@ LCL_NotifyLeap(int leap)
 void
 LCL_AccumulateFrequencyAndOffset(double dfreq, double doffset, double corr_rate)
 {
-  struct timeval raw, cooked;
+  struct timespec raw, cooked;
   double old_freq_ppm;
 
   LCL_ReadRawTime(&raw);
@@ -596,7 +613,7 @@ LCL_AccumulateFrequencyAndOffset(double dfreq, double doffset, double corr_rate)
 
   current_freq_ppm = clamp_freq(current_freq_ppm);
 
-  DEBUG_LOG(LOGF_Local, "old_freq=%.3fppm new_freq=%.3fppm offset=%.6fsec",
+  DEBUG_LOG("old_freq=%.3fppm new_freq=%.3fppm offset=%.6fsec",
       old_freq_ppm, current_freq_ppm, doffset);
 
   /* Call the system-specific driver for setting the frequency */
@@ -643,7 +660,7 @@ lcl_RegisterSystemDrivers(lcl_ReadFrequencyDriver read_freq,
 
   current_freq_ppm = (*drv_read_freq)();
 
-  DEBUG_LOG(LOGF_Local, "Local freq=%.3fppm", current_freq_ppm);
+  DEBUG_LOG("Local freq=%.3fppm", current_freq_ppm);
 }
 
 /* ================================================== */
@@ -653,7 +670,7 @@ lcl_RegisterSystemDrivers(lcl_ReadFrequencyDriver read_freq,
 int
 LCL_MakeStep(void)
 {
-  struct timeval raw;
+  struct timespec raw;
   double correction;
 
   LCL_ReadRawTime(&raw);
@@ -667,7 +684,7 @@ LCL_MakeStep(void)
   if (!LCL_ApplyStepOffset(-correction))
     return 0;
 
-  LOG(LOGS_WARN, LOGF_Local, "System clock was stepped by %.6f seconds", correction);
+  LOG(LOGS_WARN, "System clock was stepped by %.6f seconds", correction);
 
   return 1;
 }
@@ -683,10 +700,10 @@ LCL_CanSystemLeap(void)
 /* ================================================== */
 
 void
-LCL_SetSystemLeap(int leap)
+LCL_SetSystemLeap(int leap, int tai_offset)
 {
   if (drv_set_leap) {
-    (drv_set_leap)(leap);
+    (drv_set_leap)(leap, tai_offset);
   }
 }
 

local.h

@@ -31,9 +31,8 @@
 
 #include "sysincl.h"
 
-/* Read the system clock.  This is analogous to gettimeofday(),
-   but with the timezone information ignored */
-extern void LCL_ReadRawTime(struct timeval *);
+/* Read the system clock */
+extern void LCL_ReadRawTime(struct timespec *ts);
 
 /* Read the system clock, corrected according to all accumulated
    drifts and uncompensated offsets.
@@ -44,15 +43,15 @@ extern void LCL_ReadRawTime(struct timeval *);
    adjtime()-like interface to correct offsets, and to adjust the
    frequency), we must correct the raw time to get this value */
 
-extern void LCL_ReadCookedTime(struct timeval *t, double *err);
+extern void LCL_ReadCookedTime(struct timespec *ts, double *err);
 
 /* Convert raw time to cooked. */
-extern void LCL_CookTime(struct timeval *raw, struct timeval *cooked, double *err);
+extern void LCL_CookTime(struct timespec *raw, struct timespec *cooked, double *err);
 
 /* Read the current offset between the system clock and true time
    (i.e. 'cooked' - 'raw') (in seconds). */
 
-extern void LCL_GetOffsetCorrection(struct timeval *raw, double *correction, double *err);
+extern void LCL_GetOffsetCorrection(struct timespec *raw, double *correction, double *err);
 
 /* Type of routines that may be invoked as callbacks when there is a
    change to the frequency or offset.
@@ -79,7 +78,7 @@ typedef enum {
 } LCL_ChangeType;
 
 typedef void (*LCL_ParameterChangeHandler)
-     (struct timeval *raw, struct timeval *cooked,
+     (struct timespec *raw, struct timespec *cooked,
       double dfreq,
       double doffset,
       LCL_ChangeType change_type,
@@ -163,7 +162,7 @@ extern int LCL_ApplyStepOffset(double offset);
 
 /* Routine to invoke notify handlers on an unexpected time jump
    in system clock */
-extern void LCL_NotifyExternalTimeStep(struct timeval *raw, struct timeval *cooked,
+extern void LCL_NotifyExternalTimeStep(struct timespec *raw, struct timespec *cooked,
     double offset, double dispersion);
 
 /* Routine to invoke notify handlers on leap second when the system clock
@@ -202,10 +201,11 @@ extern int LCL_MakeStep(void);
    does something */
 extern int LCL_CanSystemLeap(void);
 
-/* Routine to set the system clock to correct itself for a leap second if
-   supported.  Leap second will be inserted at the end of the day if the
-   argument is positive, deleted if negative, and zero resets the setting. */
-extern void LCL_SetSystemLeap(int leap);
+/* Routine to set the system clock to correct itself for a leap second and also
+   set its TAI-UTC offset.  If supported, leap second will be inserted at the
+   end of the day if the argument is positive, deleted if negative, and zero
+   resets the setting. */
+extern void LCL_SetSystemLeap(int leap, int tai_offset);
 
 /* Routine to set a frequency correction (in ppm) that should be applied
    to local clock to compensate for temperature changes.  A positive

localp.h

@@ -52,10 +52,10 @@ typedef int (*lcl_ApplyStepOffsetDriver)(double offset);
 /* System driver to convert a raw time to an adjusted (cooked) time.
    The number of seconds returned in 'corr' have to be added to the
    raw time to get the corrected time */
-typedef void (*lcl_OffsetCorrectionDriver)(struct timeval *raw, double *corr, double *err);
+typedef void (*lcl_OffsetCorrectionDriver)(struct timespec *raw, double *corr, double *err);
 
-/* System driver to schedule leap second */
-typedef void (*lcl_SetLeapDriver)(int leap);
+/* System driver to schedule leap seconds and set TAI-UTC offset */
+typedef void (*lcl_SetLeapDriver)(int leap, int tai_offset);
 
 /* System driver to set the synchronisation status */
 typedef void (*lcl_SetSyncStatusDriver)(int synchronised, double est_error, double max_error);

logging.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2011-2014
+ * Copyright (C) Miroslav Lichvar  2011-2014, 2018
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -29,25 +29,24 @@
 
 #include "sysincl.h"
 
+#include <syslog.h>
+
 #include "conf.h"
 #include "logging.h"
 #include "util.h"
 
 /* This is used by DEBUG_LOG macro */
-int log_debug_enabled = 0;
+LOG_Severity log_min_severity = LOGS_INFO;
 
 /* ================================================== */
 /* Flag indicating we have initialised */
 static int initialised = 0;
 
+static FILE *file_log = NULL;
 static int system_log = 0;
 
 static int parent_fd = 0;
 
-#define DEBUG_LEVEL_PRINT_FUNCTION 2
-#define DEBUG_LEVEL_PRINT_DEBUG 2
-static int debug_level = 0;
-
 struct LogFile {
   const char *name;
   const char *banner;
@@ -69,6 +68,7 @@ void
 LOG_Initialise(void)
 {
   initialised = 1;
+  LOG_OpenFileLog(NULL);
 }
 
 /* ================================================== */
@@ -77,9 +77,11 @@ LOG_Initialise(void)
 void
 LOG_Finalise(void)
 {
-  if (system_log) {
+  if (system_log)
     closelog();
-  }
+
+  if (file_log)
+    fclose(file_log);
 
   LOG_CycleLogFiles();
 
@@ -112,8 +114,8 @@ static void log_message(int fatal, LOG_Severity severity, const char *message)
         assert(0);
     }
     syslog(priority, fatal ? "Fatal error : %s" : "%s", message);
-  } else {
-    fprintf(stderr, fatal ? "Fatal error : %s\n" : "%s\n", message);
+  } else if (file_log) {
+    fprintf(file_log, fatal ? "Fatal error : %s\n" : "%s\n", message);
   }
 }
 
@@ -121,25 +123,26 @@ static void log_message(int fatal, LOG_Severity severity, const char *message)
 
 void LOG_Message(LOG_Severity severity,
 #if DEBUG > 0
-                 LOG_Facility facility, int line_number,
-                 const char *filename, const char *function_name,
+                 int line_number, const char *filename, const char *function_name,
 #endif
                  const char *format, ...)
 {
   char buf[2048];
   va_list other_args;
   time_t t;
-  struct tm stm;
+  struct tm *tm;
 
-  if (!system_log) {
+  if (!system_log && file_log && severity >= log_min_severity) {
     /* Don't clutter up syslog with timestamps and internal debugging info */
     time(&t);
-    stm = *gmtime(&t);
-    strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%SZ", &stm);
-    fprintf(stderr, "%s ", buf);
+    tm = gmtime(&t);
+    if (tm) {
+      strftime(buf, sizeof (buf), "%Y-%m-%dT%H:%M:%SZ", tm);
+      fprintf(file_log, "%s ", buf);
+    }
 #if DEBUG > 0
-    if (debug_level >= DEBUG_LEVEL_PRINT_FUNCTION)
-      fprintf(stderr, "%s:%d:(%s) ", filename, line_number, function_name);
+    if (log_min_severity <= LOGS_DEBUG)
+      fprintf(file_log, "%s:%d:(%s) ", filename, line_number, function_name);
 #endif
   }
 
@@ -152,28 +155,52 @@ void LOG_Message(LOG_Severity severity,
     case LOGS_INFO:
     case LOGS_WARN:
     case LOGS_ERR:
-      log_message(0, severity, buf);
+      if (severity >= log_min_severity)
+        log_message(0, severity, buf);
       break;
     case LOGS_FATAL:
-      log_message(1, severity, buf);
+      if (severity >= log_min_severity)
+        log_message(1, severity, buf);
 
-      /* With syslog, send the message also to the grandparent
-         process or write it to stderr if not detached */
-      if (system_log) {
-        if (parent_fd > 0) {
-          if (write(parent_fd, buf, strlen(buf) + 1) < 0)
-            ; /* Not much we can do here */
-        } else if (parent_fd == 0) {
-          system_log = 0;
-          log_message(1, severity, buf);
-        }
+      /* Send the message also to the foreground process if it is
+         still running, or stderr if it is still open */
+      if (parent_fd > 0) {
+        if (write(parent_fd, buf, strlen(buf) + 1) < 0)
+          ; /* Not much we can do here */
+      } else if (system_log && parent_fd == 0) {
+        system_log = 0;
+        log_message(1, severity, buf);
       }
+      exit(1);
       break;
     default:
       assert(0);
   }
 }
 
+/* ================================================== */
+
+void
+LOG_OpenFileLog(const char *log_file)
+{
+  FILE *f;
+
+  if (log_file) {
+    f = UTI_OpenFile(NULL, log_file, NULL, 'A', 0640);
+  } else {
+    f = stderr;
+  }
+
+  /* Enable line buffering */
+  setvbuf(f, NULL, _IOLBF, BUFSIZ);
+
+  if (file_log && file_log != stderr)
+    fclose(file_log);
+
+  file_log = f;
+}
+
+
 /* ================================================== */
 
 void
@@ -185,12 +212,10 @@ LOG_OpenSystemLog(void)
 
 /* ================================================== */
 
-void LOG_SetDebugLevel(int level)
+void LOG_SetMinSeverity(LOG_Severity severity)
 {
-  debug_level = level;
-  if (level >= DEBUG_LEVEL_PRINT_DEBUG) {
-    log_debug_enabled = 1;
-  }
+  /* Don't print any debug messages in a non-debug build */
+  log_min_severity = CLAMP(DEBUG > 0 ? LOGS_DEBUG : LOGS_INFO, severity, LOGS_FATAL);
 }
 
 /* ================================================== */
@@ -199,6 +224,8 @@ void
 LOG_SetParentFd(int fd)
 {
   parent_fd = fd;
+  if (file_log == stderr)
+    file_log = NULL;
 }
 
 /* ================================================== */
@@ -238,18 +265,20 @@ LOG_FileWrite(LOG_FileID id, const char *format, ...)
     return;
 
   if (!logfiles[id].file) {
-    char filename[512];
+    char *logdir = CNF_GetLogDir();
 
-    if (snprintf(filename, sizeof(filename), "%s/%s.log",
-          CNF_GetLogDir(), logfiles[id].name) >= sizeof(filename) ||
-        !(logfiles[id].file = fopen(filename, "a"))) {
-      LOG(LOGS_WARN, LOGF_Refclock, "Couldn't open logfile %s for update", filename);
+    if (logdir[0] == '\0') {
+      LOG(LOGS_WARN, "logdir not specified");
       logfiles[id].name = NULL;
       return;
     }
 
-    /* Close on exec */
-    UTI_FdSetCloexec(fileno(logfiles[id].file));
+    logfiles[id].file = UTI_OpenFile(logdir, logfiles[id].name, ".log", 'a', 0644);
+    if (!logfiles[id].file) {
+      /* Disable the log */
+      logfiles[id].name = NULL;
+      return;
+    }
   }
 
   banner = CNF_GetLogBanner();
@@ -257,7 +286,7 @@ LOG_FileWrite(LOG_FileID id, const char *format, ...)
     char bannerline[256];
     int i, bannerlen;
 
-    bannerlen = strlen(logfiles[id].banner);
+    bannerlen = MIN(strlen(logfiles[id].banner), sizeof (bannerline) - 1);
 
     for (i = 0; i < bannerlen; i++)
       bannerline[i] = '=';

logging.h

@@ -31,9 +31,6 @@
 
 #include "sysincl.h"
 
-/* Flag indicating whether debug messages are logged */
-extern int log_debug_enabled;
-
 /* Line logging macros.  If the compiler is GNU C, we take advantage of
    being able to get the function name also. */
 
@@ -46,76 +43,38 @@ extern int log_debug_enabled;
 #endif
 
 #if DEBUG > 0
-#define LOG_MESSAGE(severity, facility, ...) \
-  LOG_Message(LOGS_DEBUG, facility, __LINE__, __FILE__, FUNCTION_NAME, __VA_ARGS__);
+#define LOG_MESSAGE(severity, ...) \
+  LOG_Message(severity, __LINE__, __FILE__, FUNCTION_NAME, __VA_ARGS__)
 #else
-#define LOG_MESSAGE(severity, facility, ...) \
-  LOG_Message(severity, __VA_ARGS__);
+#define LOG_MESSAGE(severity, ...) \
+  LOG_Message(severity, __VA_ARGS__)
 #endif
 
-#define DEBUG_LOG(facility, ...) \
+#define DEBUG_LOG(...) \
   do { \
-    if (DEBUG && log_debug_enabled) \
-      LOG_MESSAGE(LOGS_DEBUG, facility, __VA_ARGS__); \
+    if (DEBUG && log_min_severity == LOGS_DEBUG) \
+      LOG_MESSAGE(LOGS_DEBUG, __VA_ARGS__); \
   } while (0)
 
-#define LOG_FATAL(facility, ...) \
+#define LOG_FATAL(...) \
   do { \
-    LOG_MESSAGE(LOGS_FATAL, facility, __VA_ARGS__); \
+    LOG_MESSAGE(LOGS_FATAL, __VA_ARGS__); \
     exit(1); \
   } while (0)
 
-#define LOG(severity, facility, ...) LOG_MESSAGE(severity, facility, __VA_ARGS__)
+#define LOG(severity, ...) LOG_MESSAGE(severity, __VA_ARGS__)
 
 /* Definition of severity */
 typedef enum {
-  LOGS_INFO,
+  LOGS_DEBUG = -1,
+  LOGS_INFO = 0,
   LOGS_WARN,
   LOGS_ERR,
   LOGS_FATAL,
-  LOGS_DEBUG
 } LOG_Severity;
 
-/* Definition of facility.  Each message is tagged with who generated
-   it, so that the user can customise what level of reporting he gets
-   for each area of the software */
-typedef enum {
-  LOGF_Reference,
-  LOGF_NtpIO,
-  LOGF_NtpCore,
-  LOGF_NtpSources,
-  LOGF_Scheduler,
-  LOGF_SourceStats,
-  LOGF_Sources,
-  LOGF_Local,
-  LOGF_Util,
-  LOGF_Main,
-  LOGF_Memory,
-  LOGF_Client,
-  LOGF_ClientLog,
-  LOGF_Configure,
-  LOGF_CmdMon,
-  LOGF_Acquire,
-  LOGF_Manual,
-  LOGF_Keys,
-  LOGF_Logging,
-  LOGF_Nameserv,
-  LOGF_Rtc,
-  LOGF_Regress,
-  LOGF_Sys,
-  LOGF_SysGeneric,
-  LOGF_SysLinux,
-  LOGF_SysMacOSX,
-  LOGF_SysNetBSD,
-  LOGF_SysSolaris,
-  LOGF_SysSunOS,
-  LOGF_SysTimex,
-  LOGF_SysWinnt,
-  LOGF_TempComp,
-  LOGF_RtcLinux,
-  LOGF_Refclock,
-  LOGF_Smooth,
-} LOG_Facility;
+/* Minimum severity of messages to be logged */
+extern LOG_Severity log_min_severity;
 
 /* Init function */
 extern void LOG_Initialise(void);
@@ -125,26 +84,26 @@ extern void LOG_Finalise(void);
 
 /* Line logging function */
 #if DEBUG > 0
-FORMAT_ATTRIBUTE_PRINTF(6, 7)
-extern void LOG_Message(LOG_Severity severity, LOG_Facility facility,
-                        int line_number, const char *filename,
+FORMAT_ATTRIBUTE_PRINTF(5, 6)
+extern void LOG_Message(LOG_Severity severity, int line_number, const char *filename,
                         const char *function_name, const char *format, ...);
 #else
 FORMAT_ATTRIBUTE_PRINTF(2, 3)
 extern void LOG_Message(LOG_Severity severity, const char *format, ...);
 #endif
 
-/* Set debug level:
-   0, 1 - only non-debug messages are logged
-   2    - debug messages are logged too, all messages are prefixed with
-          filename, line, and function name
-   */
-extern void LOG_SetDebugLevel(int level);
+/* Set the minimum severity of a message to be logged or printed to terminal.
+   If the severity is LOGS_DEBUG and DEBUG is enabled, all messages will be
+   prefixed with the filename, line number, and function name. */
+extern void LOG_SetMinSeverity(LOG_Severity severity);
+
+/* Log messages to a file instead of stderr, or stderr again if NULL */
+extern void LOG_OpenFileLog(const char *log_file);
 
 /* Log messages to syslog instead of stderr */
 extern void LOG_OpenSystemLog(void);
 
-/* Send fatal message also to the foreground process */
+/* Stop using stderr and send fatal message to the foreground process */
 extern void LOG_SetParentFd(int fd);
 
 /* Close the pipe to the foreground process so it can exit */

main.c

@@ -4,7 +4,7 @@
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
  * Copyright (C) John G. Hasler  2009
- * Copyright (C) Miroslav Lichvar  2012-2015
+ * Copyright (C) Miroslav Lichvar  2012-2018
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -35,8 +35,13 @@
 #include "local.h"
 #include "sys.h"
 #include "ntp_io.h"
+#include "ntp_signd.h"
 #include "ntp_sources.h"
 #include "ntp_core.h"
+#include "nts_ke_client.h"
+#include "nts_ke_server.h"
+#include "nts_ntp_server.h"
+#include "socket.h"
 #include "sources.h"
 #include "sourcestats.h"
 #include "reference.h"
@@ -49,6 +54,7 @@
 #include "refclock.h"
 #include "clientlog.h"
 #include "nameserv.h"
+#include "privops.h"
 #include "smooth.h"
 #include "tempcomp.h"
 #include "util.h"
@@ -68,12 +74,28 @@ static REF_Mode ref_mode = REF_ModeNormal;
 
 /* ================================================== */
 
+static void
+do_platform_checks(void)
+{
+  /* Require at least 32-bit integers, two's complement representation and
+     the usual implementation of conversion of unsigned integers */
+  assert(sizeof (int) >= 4);
+  assert(-1 == ~0);
+  assert((int32_t)4294967295U == (int32_t)-1);
+}
+
+/* ================================================== */
+
 static void
 delete_pidfile(void)
 {
   const char *pidfile = CNF_GetPidFile();
-  /* Don't care if this fails, there's not a lot we can do */
-  unlink(pidfile);
+
+  if (!pidfile[0])
+    return;
+
+  if (!UTI_RemoveFile(NULL, pidfile, NULL))
+    ;
 }
 
 /* ================================================== */
@@ -83,7 +105,7 @@ MAI_CleanupAndExit(void)
 {
   if (!initialised) exit(exit_status);
   
-  if (CNF_GetDumpOnExit()) {
+  if (CNF_GetDumpDir()[0] != '\0') {
     SRC_DumpSources();
   }
 
@@ -94,11 +116,16 @@ MAI_CleanupAndExit(void)
   TMC_Finalise();
   MNL_Finalise();
   CLG_Finalise();
+  NKC_Finalise();
+  NKS_Finalise();
+  NNS_Finalise();
+  NSD_Finalise();
   NSR_Finalise();
   SST_Finalise();
   NCR_Finalise();
   NIO_Finalise();
   CAM_Finalise();
+  SCK_Finalise();
   KEY_Finalise();
   RCL_Finalise();
   SRC_Finalise();
@@ -107,13 +134,13 @@ MAI_CleanupAndExit(void)
   SYS_Finalise();
   SCH_Finalise();
   LCL_Finalise();
+  PRV_Finalise();
 
   delete_pidfile();
   
   CNF_Finalise();
-  LOG_Finalise();
-
   HSH_Finalise();
+  LOG_Finalise();
 
   exit(exit_status);
 }
@@ -129,6 +156,16 @@ signal_cleanup(int x)
 
 /* ================================================== */
 
+static void
+quit_timeout(void *arg)
+{
+  /* Return with non-zero status if the clock is not synchronised */
+  exit_status = REF_GetOurStratum() >= NTP_MAX_STRATUM;
+  SCH_QuitProgram();
+}
+
+/* ================================================== */
+
 static void
 ntp_source_resolving_end(void)
 {
@@ -142,6 +179,7 @@ ntp_source_resolving_end(void)
     SRC_ReloadSources();
   }
 
+  SRC_RemoveDumpFiles();
   RTC_StartMeasurements();
   RCL_StartRefclocks();
   NSR_StartSources();
@@ -215,63 +253,54 @@ post_init_rtc_hook(void *anything)
 }
 
 /* ================================================== */
-/* Return 1 if the process exists on the system. */
 
-static int
-does_process_exist(int pid)
-{
-  int status;
-  status = getsid(pid);
-  if (status >= 0) {
-    return 1;
-  } else {
-    return 0;
-  }
-}
-
-/* ================================================== */
-
-static int
-maybe_another_chronyd_running(int *other_pid)
+static void
+check_pidfile(void)
 {
   const char *pidfile = CNF_GetPidFile();
   FILE *in;
   int pid, count;
   
-  *other_pid = 0;
+  if (!pidfile[0])
+    return;
 
-  in = fopen(pidfile, "r");
-  if (!in) return 0;
+  in = UTI_OpenFile(NULL, pidfile, NULL, 'r', 0);
+  if (!in)
+    return;
 
   count = fscanf(in, "%d", &pid);
   fclose(in);
   
-  if (count != 1) return 0;
+  if (count != 1)
+    return;
 
-  *other_pid = pid;
-  return does_process_exist(pid);
-  
+  if (getsid(pid) < 0)
+    return;
+
+  LOG_FATAL("Another chronyd may already be running (pid=%d), check %s",
+            pid, pidfile);
 }
 
 /* ================================================== */
 
 static void
-write_lockfile(void)
+write_pidfile(void)
 {
   const char *pidfile = CNF_GetPidFile();
   FILE *out;
 
-  out = fopen(pidfile, "w");
-  if (!out) {
-    LOG_FATAL(LOGF_Main, "could not open lockfile %s for writing", pidfile);
-  } else {
-    fprintf(out, "%d\n", (int)getpid());
-    fclose(out);
-  }
+  if (!pidfile[0])
+    return;
+
+  out = UTI_OpenFile(NULL, pidfile, NULL, 'W', 0644);
+  fprintf(out, "%d\n", (int)getpid());
+  fclose(out);
 }
 
 /* ================================================== */
 
+#define DEV_NULL "/dev/null"
+
 static void
 go_daemon(void)
 {
@@ -280,14 +309,14 @@ go_daemon(void)
   /* Create pipe which will the daemon use to notify the grandparent
      when it's initialised or send an error message */
   if (pipe(pipefd)) {
-    LOG_FATAL(LOGF_Logging, "Could not detach, pipe failed : %s", strerror(errno));
+    LOG_FATAL("pipe() failed : %s", strerror(errno));
   }
 
   /* Does this preserve existing signal handlers? */
   pid = fork();
 
   if (pid < 0) {
-    LOG_FATAL(LOGF_Logging, "Could not detach, fork failed : %s", strerror(errno));
+    LOG_FATAL("fork() failed : %s", strerror(errno));
   } else if (pid > 0) {
     /* In the 'grandparent' */
     char message[1024];
@@ -298,7 +327,8 @@ go_daemon(void)
     if (r) {
       if (r > 0) {
         /* Print the error message from the child */
-        fprintf(stderr, "%.1024s\n", message);
+        message[sizeof (message) - 1] = '\0';
+        fprintf(stderr, "%s\n", message);
       }
       exit(1);
     } else
@@ -312,7 +342,7 @@ go_daemon(void)
     pid = fork();
 
     if (pid < 0) {
-      LOG_FATAL(LOGF_Logging, "Could not detach, fork failed : %s", strerror(errno));
+      LOG_FATAL("fork() failed : %s", strerror(errno));
     } else if (pid > 0) {
       exit(0); /* In the 'parent' */
     } else {
@@ -320,7 +350,7 @@ go_daemon(void)
 
       /* Change current directory to / */
       if (chdir("/") < 0) {
-        LOG_FATAL(LOGF_Logging, "Could not chdir to / : %s", strerror(errno));
+        LOG_FATAL("chdir() failed : %s", strerror(errno));
       }
 
       /* Don't keep stdin/out/err from before. But don't close
@@ -331,145 +361,207 @@ go_daemon(void)
       }
 
       LOG_SetParentFd(pipefd[1]);
+
+      /* Open /dev/null as new stdin/out/err */
+      errno = 0;
+      if (open(DEV_NULL, O_RDONLY) != STDIN_FILENO ||
+          open(DEV_NULL, O_WRONLY) != STDOUT_FILENO ||
+          open(DEV_NULL, O_RDWR) != STDERR_FILENO)
+        LOG_FATAL("Could not open %s : %s", DEV_NULL, strerror(errno));
     }
   }
 }
 
 /* ================================================== */
 
+static void
+print_help(const char *progname)
+{
+      printf("Usage: %s [-4|-6] [-n|-d] [-q|-Q] [-r] [-R] [-s] [-t TIMEOUT] [-f FILE|COMMAND...]\n",
+             progname);
+}
+
+/* ================================================== */
+
+static void
+print_version(void)
+{
+  printf("chronyd (chrony) version %s (%s)\n", CHRONY_VERSION, CHRONYD_FEATURES);
+}
+
+/* ================================================== */
+
+static int
+parse_int_arg(const char *arg)
+{
+  int i;
+
+  if (sscanf(arg, "%d", &i) != 1)
+    LOG_FATAL("Invalid argument %s", arg);
+  return i;
+}
+
+/* ================================================== */
+
 int main
 (int argc, char **argv)
 {
   const char *conf_file = DEFAULT_CONF_FILE;
   const char *progname = argv[0];
-  char *user = NULL;
+  char *user = NULL, *log_file = NULL;
   struct passwd *pw;
-  int debug = 0, nofork = 0, address_family = IPADDR_UNSPEC;
-  int do_init_rtc = 0, restarted = 0;
-  int other_pid;
+  int opt, debug = 0, nofork = 0, address_family = IPADDR_UNSPEC;
+  int do_init_rtc = 0, restarted = 0, client_only = 0, timeout = -1;
   int scfilter_level = 0, lock_memory = 0, sched_priority = 0;
-  int system_log = 1;
+  int clock_control = 1, system_log = 1, log_severity = LOGS_INFO;
   int config_args = 0;
 
+  do_platform_checks();
+
   LOG_Initialise();
 
-  /* Parse command line options */
-  while (++argv, (--argc)>0) {
-
-    if (!strcmp("-f", *argv)) {
-      ++argv, --argc;
-      conf_file = *argv;
-    } else if (!strcmp("-P", *argv)) {
-      ++argv, --argc;
-      if (argc == 0 || sscanf(*argv, "%d", &sched_priority) != 1) {
-        LOG_FATAL(LOGF_Main, "Bad scheduler priority");
-      }
-    } else if (!strcmp("-m", *argv)) {
-      lock_memory = 1;
-    } else if (!strcmp("-r", *argv)) {
-      reload = 1;
-    } else if (!strcmp("-R", *argv)) {
-      restarted = 1;
-    } else if (!strcmp("-u", *argv)) {
-      ++argv, --argc;
-      if (argc == 0) {
-        LOG_FATAL(LOGF_Main, "Missing user name");
-      } else {
-        user = *argv;
-      }
-    } else if (!strcmp("-F", *argv)) {
-      ++argv, --argc;
-      if (argc == 0 || sscanf(*argv, "%d", &scfilter_level) != 1)
-        LOG_FATAL(LOGF_Main, "Bad syscall filter level");
-    } else if (!strcmp("-s", *argv)) {
-      do_init_rtc = 1;
-    } else if (!strcmp("-v", *argv) || !strcmp("--version",*argv)) {
-      /* This write to the terminal is OK, it comes before we turn into a daemon */
-      printf("chronyd (chrony) version %s (%s)\n", CHRONY_VERSION, CHRONYD_FEATURES);
+  /* Parse (undocumented) long command-line options */
+  for (optind = 1; optind < argc; optind++) {
+    if (!strcmp("--help", argv[optind])) {
+      print_help(progname);
       return 0;
-    } else if (!strcmp("-n", *argv)) {
-      nofork = 1;
-    } else if (!strcmp("-d", *argv)) {
-      debug++;
-      nofork = 1;
-      system_log = 0;
-    } else if (!strcmp("-q", *argv)) {
-      ref_mode = REF_ModeUpdateOnce;
-      nofork = 1;
-      system_log = 0;
-    } else if (!strcmp("-Q", *argv)) {
-      ref_mode = REF_ModePrintOnce;
-      nofork = 1;
-      system_log = 0;
-    } else if (!strcmp("-4", *argv)) {
-      address_family = IPADDR_INET4;
-    } else if (!strcmp("-6", *argv)) {
-      address_family = IPADDR_INET6;
-    } else if (!strcmp("-h", *argv) || !strcmp("--help", *argv)) {
-      printf("Usage: %s [-4|-6] [-n|-d] [-q|-Q] [-r] [-R] [-s] [-f FILE|COMMAND...]\n",
-             progname);
+    } else if (!strcmp("--version", argv[optind])) {
+      print_version();
       return 0;
-    } else if (*argv[0] == '-') {
-      LOG_FATAL(LOGF_Main, "Unrecognized command line option [%s]", *argv);
-    } else {
-      /* Process remaining arguments and configuration lines */
-      config_args = argc;
-      break;
     }
   }
 
-  if (getuid() != 0) {
-    /* This write to the terminal is OK, it comes before we turn into a daemon */
-    fprintf(stderr,"Not superuser\n");
-    return 1;
+  optind = 1;
+
+  /* Parse short command-line options */
+  while ((opt = getopt(argc, argv, "46df:F:hl:L:mnP:qQrRst:u:vx")) != -1) {
+    switch (opt) {
+      case '4':
+      case '6':
+        address_family = opt == '4' ? IPADDR_INET4 : IPADDR_INET6;
+        break;
+      case 'd':
+        debug++;
+        nofork = 1;
+        system_log = 0;
+        break;
+      case 'f':
+        conf_file = optarg;
+        break;
+      case 'F':
+        scfilter_level = parse_int_arg(optarg);
+        break;
+      case 'l':
+        log_file = optarg;
+        break;
+      case 'L':
+        log_severity = parse_int_arg(optarg);
+        break;
+      case 'm':
+        lock_memory = 1;
+        break;
+      case 'n':
+        nofork = 1;
+        break;
+      case 'P':
+        sched_priority = parse_int_arg(optarg);
+        break;
+      case 'q':
+        ref_mode = REF_ModeUpdateOnce;
+        nofork = 1;
+        client_only = 0;
+        system_log = 0;
+        break;
+      case 'Q':
+        ref_mode = REF_ModePrintOnce;
+        nofork = 1;
+        client_only = 1;
+        clock_control = 0;
+        system_log = 0;
+        break;
+      case 'r':
+        reload = 1;
+        break;
+      case 'R':
+        restarted = 1;
+        break;
+      case 's':
+        do_init_rtc = 1;
+        break;
+      case 't':
+        timeout = parse_int_arg(optarg);
+        break;
+      case 'u':
+        user = optarg;
+        break;
+      case 'v':
+        print_version();
+        return 0;
+      case 'x':
+        clock_control = 0;
+        break;
+      default:
+        print_help(progname);
+        return opt != 'h';
+    }
   }
 
+  if (getuid() && !client_only)
+    LOG_FATAL("Not superuser");
+
   /* Turn into a daemon */
   if (!nofork) {
     go_daemon();
   }
 
-  if (system_log) {
+  if (log_file) {
+    LOG_OpenFileLog(log_file);
+  } else if (system_log) {
     LOG_OpenSystemLog();
   }
   
-  LOG_SetDebugLevel(debug);
+  LOG_SetMinSeverity(debug >= 2 ? LOGS_DEBUG : log_severity);
   
-  LOG(LOGS_INFO, LOGF_Main, "chronyd version %s starting (%s)",
-      CHRONY_VERSION, CHRONYD_FEATURES);
+  LOG(LOGS_INFO, "chronyd version %s starting (%s)", CHRONY_VERSION, CHRONYD_FEATURES);
 
   DNS_SetAddressFamily(address_family);
 
-  CNF_Initialise(restarted);
+  CNF_Initialise(restarted, client_only);
 
   /* Parse the config file or the remaining command line arguments */
+  config_args = argc - optind;
   if (!config_args) {
     CNF_ReadFile(conf_file);
   } else {
-    do {
-      CNF_ParseLine(NULL, config_args - argc + 1, *argv);
-    } while (++argv, --argc);
+    for (; optind < argc; optind++)
+      CNF_ParseLine(NULL, config_args + optind - argc + 1, argv[optind]);
   }
 
-  /* Check whether another chronyd may already be running.  Do this after
-   * forking, so that message logging goes to the right place (i.e. syslog), in
-   * case this chronyd is being run from a boot script. */
-  if (maybe_another_chronyd_running(&other_pid)) {
-    LOG_FATAL(LOGF_Main, "Another chronyd may already be running (pid=%d), check lockfile (%s)",
-              other_pid, CNF_GetPidFile());
-  }
+  /* Check whether another chronyd may already be running */
+  check_pidfile();
 
-  /* Write our lockfile to prevent other chronyds running.  This has *GOT* to
-   * be done *AFTER* the daemon-creation fork() */
-  write_lockfile();
+  if (!user)
+    user = CNF_GetUser();
 
+  pw = getpwnam(user);
+  if (!pw)
+    LOG_FATAL("Could not get user/group ID of %s", user);
+
+  /* Create directories for sockets, log files, and dump files */
+  CNF_CreateDirs(pw->pw_uid, pw->pw_gid);
+
+  /* Write our pidfile to prevent other instances from running */
+  write_pidfile();
+
+  PRV_Initialise();
   LCL_Initialise();
   SCH_Initialise();
-  SYS_Initialise();
+  SYS_Initialise(clock_control);
   RTC_Initialise(do_init_rtc);
   SRC_Initialise();
   RCL_Initialise();
   KEY_Initialise();
+  SCK_Initialise();
 
   /* Open privileged ports before dropping root */
   CAM_Initialise(address_family);
@@ -489,23 +581,17 @@ int main
     SYS_LockMemory();
   }
 
-  if (!user) {
-    user = CNF_GetUser();
-  }
-
-  if ((pw = getpwnam(user)) == NULL)
-    LOG_FATAL(LOGF_Main, "Could not get %s uid/gid", user);
-
-  /* Create all directories before dropping root */
-  CNF_CreateDirs(pw->pw_uid, pw->pw_gid);
-
-  /* Drop root privileges if the user has non-zero uid or gid */
-  if (pw->pw_uid || pw->pw_gid)
+  /* Drop root privileges if the specified user has a non-zero UID */
+  if (!geteuid() && (pw->pw_uid || pw->pw_gid))
     SYS_DropRoot(pw->pw_uid, pw->pw_gid);
 
   REF_Initialise();
   SST_Initialise();
   NSR_Initialise();
+  NSD_Initialise();
+  NNS_Initialise();
+  NKS_Initialise(scfilter_level);
+  NKC_Initialise();
   CLG_Initialise();
   MNL_Initialise();
   TMC_Initialise();
@@ -514,12 +600,12 @@ int main
   /* From now on, it is safe to do finalisation on exit */
   initialised = 1;
 
-  UTI_SetQuitSignalsHandler(signal_cleanup);
+  UTI_SetQuitSignalsHandler(signal_cleanup, 1);
 
   CAM_OpenUnixSocket();
 
   if (scfilter_level)
-    SYS_EnableSystemCallFilter(scfilter_level);
+    SYS_EnableSystemCallFilter(scfilter_level, SYS_MAIN_PROCESS);
 
   if (ref_mode == REF_ModeNormal && CNF_GetInitSources() > 0) {
     ref_mode = REF_ModeInitStepSlew;
@@ -528,6 +614,9 @@ int main
   REF_SetModeEndHandler(reference_mode_end);
   REF_SetMode(ref_mode);
 
+  if (timeout >= 0)
+    SCH_AddTimeoutByDelay(timeout, quit_timeout, NULL);
+
   if (do_init_rtc) {
     RTC_TimeInit(post_init_rtc_hook, NULL);
   } else {
@@ -538,7 +627,7 @@ int main
      the scheduler. */
   SCH_MainLoop();
 
-  LOG(LOGS_INFO, LOGF_Main, "chronyd exiting");
+  LOG(LOGS_INFO, "chronyd exiting");
 
   MAI_CleanupAndExit();
 

make_release

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-LANG=C
+LANG=C.UTF-8
 export LANG
 
 if [ $# -ne 1 ]; then
@@ -11,7 +11,6 @@ fi
 version=$1
 tag=$version
 subdir=chrony-${version}
-mandate=$(date +'%B %Y')
 
 umask 022
 
@@ -37,31 +36,13 @@ cd RELEASES/$subdir || exit 1
 
 echo $version > version.txt
 
-sed -i -e "s%@@VERSION@@%${version}%" examples/chrony.spec
+./configure && make -C doc man txt || exit 1
 
-for m in chronyc.1.in chrony.conf.5.in chronyd.8.in; do
-  sed -e "s%@VERSION@%${version}%;s%@MAN_DATE@%${mandate}%" \
-    < $m > ${m}_
-  mv -f ${m}_ $m
-done
-
-./configure && make chrony.txt getdate.c || exit 1
-
-awk '/^[1-9] Installation$/{p=1}
-     /^[1-9]\.. Support for line editing/{exit}; p' chrony.txt | \
-  tail -n +4 > INSTALL
-
-if [ $(wc -l < INSTALL) -gt 100 -o $(wc -l < INSTALL) -lt 85 ]; then
-  echo "INSTALL generated incorrectly?"
-  exit 3
-fi
-
-a2x --lynx -f text doc/faq.adoc || exit 1
-mv doc/faq.text FAQ
-rm -rf doc
+iconv -f utf-8 -t ascii//TRANSLIT < doc/installation.txt > INSTALL
+iconv -f utf-8 -t ascii//TRANSLIT < doc/faq.txt > FAQ
 
 make distclean
-rm -f config.h config.log make_release .gitignore
+rm -f make_release .gitignore
 
 cd ..
 tar cv --owner root --group root $subdir | gzip -9 > ${subdir}.tar.gz

manual.c

@@ -47,7 +47,7 @@ static int enabled = 0;
 
 /* More recent samples at highest indices */
 typedef struct {
-  struct timeval when; /* This is our 'cooked' time */
+  struct timespec when; /* This is our 'cooked' time */
   double orig_offset; /*+ Not modified by slew samples */
   double offset; /*+ if we are fast of the supplied reference */
   double residual; /*+ regression residual (sign convention given by
@@ -64,8 +64,8 @@ static int n_samples;
 /* ================================================== */
 
 static void
-slew_samples(struct timeval *raw,
-             struct timeval *cooked, 
+slew_samples(struct timespec *raw,
+             struct timespec *cooked,
              double dfreq,
              double doffset,
              LCL_ChangeType change_type,
@@ -97,7 +97,8 @@ MNL_Finalise(void)
 /* ================================================== */
 
 static void
-estimate_and_set_system(struct timeval *now, int offset_provided, double offset, long *offset_cs, double *dfreq_ppm, double *new_afreq_ppm)
+estimate_and_set_system(struct timespec *now, int offset_provided, double offset,
+                        double *reg_offset, double *dfreq_ppm, double *new_afreq_ppm)
 {
   double agos[MAX_SAMPLES], offsets[MAX_SAMPLES];
   double b0, b1;
@@ -108,32 +109,26 @@ estimate_and_set_system(struct timeval *now, int offset_provided, double offset,
   int found_freq;
   double slew_by;
 
+  b0 = offset_provided ? offset : 0.0;
+  b1 = freq = 0.0;
+  found_freq = 0;
+
   if (n_samples > 1) {
     for (i=0; i<n_samples; i++) {
-      UTI_DiffTimevalsToDouble(&agos[i], &samples[n_samples-1].when, &samples[i].when);
+      agos[i] = UTI_DiffTimespecsToDouble(&samples[n_samples - 1].when, &samples[i].when);
       offsets[i] = samples[i].offset;
     }
     
-    RGR_FindBestRobustRegression(agos, offsets, n_samples,
-                                 1.0e-8, /* 0.01ppm easily good enough for this! */
-                                 &b0, &b1, &n_runs, &best_start);
-    
-    
-    /* Ignore b0 from regression; treat offset as being the most
-       recently entered value.  (If the administrator knows he's put
-       an outlier in, he will rerun the settime operation.)   However,
-       the frequency estimate comes from the regression. */
-    
-    freq = -b1;
-    found_freq = 1;
-  } else {
-    if (offset_provided) {
-      b0 = offset;
-    } else {
-      b0 = 0.0;
+    if (RGR_FindBestRobustRegression(agos, offsets, n_samples, 1.0e-8,
+                                     &b0, &b1, &n_runs, &best_start)) {
+      /* Ignore b0 from regression; treat offset as being the most
+         recently entered value.  (If the administrator knows he's put
+         an outlier in, he will rerun the settime operation.)   However,
+         the frequency estimate comes from the regression. */
+      freq = -b1;
+      found_freq = 1;
     }
-    b1 = freq = 0.0;
-    found_freq = 0;
+  } else {
     agos[0] = 0.0;
     offsets[0] = b0;
   }
@@ -145,21 +140,20 @@ estimate_and_set_system(struct timeval *now, int offset_provided, double offset,
   }
   
   if (found_freq) {
-    LOG(LOGS_INFO, LOGF_Manual,
-        "Making a frequency change of %.3f ppm and a slew of %.6f",
+    LOG(LOGS_INFO, "Making a frequency change of %.3f ppm and a slew of %.6f",
         1.0e6 * freq, slew_by);
     
     REF_SetManualReference(now,
                            slew_by,
                            freq, skew);
   } else {
-    LOG(LOGS_INFO, LOGF_Manual, "Making a slew of %.6f", slew_by);
+    LOG(LOGS_INFO, "Making a slew of %.6f", slew_by);
     REF_SetManualReference(now,
                            slew_by,
                            0.0, skew);
   }
   
-  if (offset_cs) *offset_cs = (long)(0.5 + 100.0 * b0);
+  if (reg_offset) *reg_offset = b0;
   if (dfreq_ppm) *dfreq_ppm = 1.0e6 * freq;
   if (new_afreq_ppm) *new_afreq_ppm = LCL_ReadAbsoluteFrequency();
   
@@ -173,9 +167,9 @@ estimate_and_set_system(struct timeval *now, int offset_provided, double offset,
 /* ================================================== */
 
 int
-MNL_AcceptTimestamp(struct timeval *ts, long *offset_cs, double *dfreq_ppm, double *new_afreq_ppm)
+MNL_AcceptTimestamp(struct timespec *ts, double *reg_offset, double *dfreq_ppm, double *new_afreq_ppm)
 {
-  struct timeval now;
+  struct timespec now;
   double offset, diff;
   int i;
 
@@ -189,12 +183,12 @@ MNL_AcceptTimestamp(struct timeval *ts, long *offset_cs, double *dfreq_ppm, doub
      return 0;
 
     if (n_samples) {
-      UTI_DiffTimevalsToDouble(&diff, &now, &samples[n_samples - 1].when);
+      diff = UTI_DiffTimespecsToDouble(&now, &samples[n_samples - 1].when);
       if (diff < MIN_SAMPLE_SEPARATION)
         return 0;
     }
 
-    UTI_DiffTimevalsToDouble(&offset, &now, ts);
+    offset = UTI_DiffTimespecsToDouble(&now, ts);
 
     /* Check if buffer full up */
     if (n_samples == MAX_SAMPLES) {
@@ -210,7 +204,7 @@ MNL_AcceptTimestamp(struct timeval *ts, long *offset_cs, double *dfreq_ppm, doub
     samples[n_samples].orig_offset = offset;
     ++n_samples;
 
-    estimate_and_set_system(&now, 1, offset, offset_cs, dfreq_ppm, new_afreq_ppm);
+    estimate_and_set_system(&now, 1, offset, reg_offset, dfreq_ppm, new_afreq_ppm);
 
     return 1;
 
@@ -224,8 +218,8 @@ MNL_AcceptTimestamp(struct timeval *ts, long *offset_cs, double *dfreq_ppm, doub
 /* ================================================== */
 
 static void
-slew_samples(struct timeval *raw,
-             struct timeval *cooked, 
+slew_samples(struct timespec *raw,
+             struct timespec *cooked,
              double dfreq,
              double doffset,
              LCL_ChangeType change_type,
@@ -239,7 +233,7 @@ slew_samples(struct timeval *raw,
   }
 
   for (i=0; i<n_samples; i++) {
-    UTI_AdjustTimeval(&samples[i].when, cooked, &samples[i].when, &delta_time,
+    UTI_AdjustTimespec(&samples[i].when, cooked, &samples[i].when, &delta_time,
         dfreq, doffset);
     samples[i].offset += delta_time;
   }
@@ -309,7 +303,7 @@ int
 MNL_DeleteSample(int index)
 {
   int i;
-  struct timeval now;
+  struct timespec now;
 
   if ((index < 0) || (index >= n_samples)) {
     return 0;

manual.h

@@ -33,7 +33,7 @@
 
 extern void MNL_Initialise(void);
 extern void MNL_Finalise(void);
-extern int MNL_AcceptTimestamp(struct timeval *ts, long *offset_cs, double *dfreq_ppm, double *new_afreq_ppm);
+extern int MNL_AcceptTimestamp(struct timespec *ts, double *reg_offset, double *dfreq_ppm, double *new_afreq_ppm);
 
 extern void MNL_Enable(void);
 extern void MNL_Disable(void);

memory.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2014
+ * Copyright (C) Miroslav Lichvar  2014, 2017
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -37,7 +37,7 @@ Malloc(size_t size)
 
   r = malloc(size);
   if (!r && size)
-    LOG_FATAL(LOGF_Memory, "Could not allocate memory");
+    LOG_FATAL("Could not allocate memory");
 
   return r;
 }
@@ -49,11 +49,37 @@ Realloc(void *ptr, size_t size)
 
   r = realloc(ptr, size);
   if (!r && size)
-    LOG_FATAL(LOGF_Memory, "Could not allocate memory");
+    LOG_FATAL("Could not allocate memory");
 
   return r;
 }
 
+static size_t
+get_array_size(size_t nmemb, size_t size)
+{
+  size_t array_size;
+
+  array_size = nmemb * size;
+
+  /* Check for overflow */
+  if (nmemb > 0 && array_size / nmemb != size)
+    LOG_FATAL("Could not allocate memory");
+
+  return array_size;
+}
+
+void *
+Malloc2(size_t nmemb, size_t size)
+{
+  return Malloc(get_array_size(nmemb, size));
+}
+
+void *
+Realloc2(void *ptr, size_t nmemb, size_t size)
+{
+  return Realloc(ptr, get_array_size(nmemb, size));
+}
+
 char *
 Strdup(const char *s)
 {
@@ -61,7 +87,7 @@ Strdup(const char *s)
 
   r = strdup(s);
   if (!r)
-    LOG_FATAL(LOGF_Memory, "Could not allocate memory");
+    LOG_FATAL("Could not allocate memory");
 
   return r;
 }

memory.h

@@ -27,15 +27,19 @@
 #ifndef GOT_MEMORY_H
 #define GOT_MEMORY_H
 
+#include "sysincl.h"
+
 /* Wrappers checking for errors */
 extern void *Malloc(size_t size);
 extern void *Realloc(void *ptr, size_t size);
+extern void *Malloc2(size_t nmemb, size_t size);
+extern void *Realloc2(void *ptr, size_t nmemb, size_t size);
 extern char *Strdup(const char *s);
 
 /* Convenient macros */
 #define MallocNew(T) ((T *) Malloc(sizeof(T)))
-#define MallocArray(T, n) ((T *) Malloc((n) * sizeof(T)))
-#define ReallocArray(T,n,x) ((T *) Realloc((void *)(x), (n)*sizeof(T)))
+#define MallocArray(T, n) ((T *) Malloc2(n, sizeof(T)))
+#define ReallocArray(T, n, x) ((T *) Realloc2((void *)(x), n, sizeof(T)))
 #define Free(x) free(x)
 
 #endif /* GOT_MEMORY_H */

nameserv.c

@@ -30,7 +30,11 @@
 
 #include "sysincl.h"
 
+#include <netdb.h>
+#include <resolv.h>
+
 #include "nameserv.h"
+#include "socket.h"
 #include "util.h"
 
 /* ================================================== */
@@ -49,10 +53,24 @@ DNS_Name2IPAddress(const char *name, IPAddr *ip_addrs, int max_addrs)
 #ifdef HAVE_GETADDRINFO
   struct addrinfo hints, *res, *ai;
   int i, result;
-  
+
+  max_addrs = MIN(max_addrs, DNS_MAX_ADDRESSES);
+
   memset(&hints, 0, sizeof (hints));
-  hints.ai_family = AF_UNSPEC;
-  hints.ai_socktype = SOCK_STREAM;
+
+  switch (address_family) {
+    case IPADDR_INET4:
+      hints.ai_family = AF_INET;
+      break;
+#ifdef FEAT_IPV6
+    case IPADDR_INET6:
+      hints.ai_family = AF_INET6;
+      break;
+#endif
+    default:
+      hints.ai_family = AF_UNSPEC;
+  }
+  hints.ai_socktype = SOCK_DGRAM;
 
   result = getaddrinfo(name, NULL, &hints, &res);
 
@@ -99,6 +117,8 @@ DNS_Name2IPAddress(const char *name, IPAddr *ip_addrs, int max_addrs)
   if (address_family != IPADDR_UNSPEC && address_family != IPADDR_INET4)
     return DNS_Failure;
 
+  max_addrs = MIN(max_addrs, DNS_MAX_ADDRESSES);
+
   host = gethostbyname(name);
 
   if (host == NULL) {
@@ -137,10 +157,14 @@ DNS_IPAddress2Name(IPAddr *ip_addr, char *name, int len)
 
 #ifdef FEAT_IPV6
   struct sockaddr_in6 in6;
+  IPSockAddr ip_saddr;
   socklen_t slen;
   char hbuf[NI_MAXHOST];
 
-  slen = UTI_IPAndPortToSockaddr(ip_addr, 0, (struct sockaddr *)&in6);
+  ip_saddr.ip_addr = *ip_addr;
+  ip_saddr.port = 0;
+
+  slen = SCK_IPSockAddrToSockaddr(&ip_saddr, (struct sockaddr *)&in6, sizeof (in6));
   if (!getnameinfo((struct sockaddr *)&in6, slen, hbuf, sizeof (hbuf), NULL, 0, 0))
     result = hbuf;
 #else

nameserv.h

@@ -39,6 +39,9 @@ typedef enum {
 /* Resolve names only to selected address family */
 extern void DNS_SetAddressFamily(int family);
 
+/* Maximum number of addresses returned by DNS_Name2IPAddress */
+#define DNS_MAX_ADDRESSES 16
+
 extern DNS_Status DNS_Name2IPAddress(const char *name, IPAddr *ip_addrs, int max_addrs);
 
 extern int DNS_IPAddress2Name(IPAddr *ip_addr, char *name, int len);

nameserv_async.c

@@ -31,20 +31,19 @@
 #include "nameserv_async.h"
 #include "logging.h"
 #include "memory.h"
+#include "privops.h"
 #include "sched.h"
 #include "util.h"
 
 #ifdef USE_PTHREAD_ASYNCDNS
 #include <pthread.h>
 
-#define MAX_ADDRESSES 16
-
 /* ================================================== */
 
 struct DNS_Async_Instance {
   const char *name;
   DNS_Status status;
-  IPAddr addresses[MAX_ADDRESSES];
+  IPAddr addresses[DNS_MAX_ADDRESSES];
   DNS_NameResolveHandler handler;
   void *arg;
 
@@ -52,7 +51,7 @@ struct DNS_Async_Instance {
   int pipe[2];
 };
 
-static int resolving_threads = 0;
+static pthread_mutex_t privops_lock = PTHREAD_MUTEX_INITIALIZER;
 
 /* ================================================== */
 
@@ -61,7 +60,9 @@ start_resolving(void *anything)
 {
   struct DNS_Async_Instance *inst = (struct DNS_Async_Instance *)anything;
 
-  inst->status = DNS_Name2IPAddress(inst->name, inst->addresses, MAX_ADDRESSES);
+  pthread_mutex_lock(&privops_lock);
+  inst->status = PRV_Name2IPAddress(inst->name, inst->addresses, DNS_MAX_ADDRESSES);
+  pthread_mutex_unlock(&privops_lock);
 
   /* Notify the main thread that the result is ready */
   if (write(inst->pipe[1], "", 1) < 0)
@@ -73,22 +74,20 @@ start_resolving(void *anything)
 /* ================================================== */
 
 static void
-end_resolving(void *anything)
+end_resolving(int fd, int event, void *anything)
 {
   struct DNS_Async_Instance *inst = (struct DNS_Async_Instance *)anything;
   int i;
 
   if (pthread_join(inst->thread, NULL)) {
-    LOG_FATAL(LOGF_Nameserv, "pthread_join() failed");
+    LOG_FATAL("pthread_join() failed");
   }
 
-  resolving_threads--;
-
-  SCH_RemoveInputFileHandler(inst->pipe[0]);
+  SCH_RemoveFileHandler(inst->pipe[0]);
   close(inst->pipe[0]);
   close(inst->pipe[1]);
 
-  for (i = 0; inst->status == DNS_Success && i < MAX_ADDRESSES &&
+  for (i = 0; inst->status == DNS_Success && i < DNS_MAX_ADDRESSES &&
               inst->addresses[i].family != IPADDR_UNSPEC; i++)
     ;
 
@@ -111,17 +110,17 @@ DNS_Name2IPAddressAsync(const char *name, DNS_NameResolveHandler handler, void *
   inst->status = DNS_Failure;
 
   if (pipe(inst->pipe)) {
-    LOG_FATAL(LOGF_Nameserv, "pipe() failed");
+    LOG_FATAL("pipe() failed");
   }
 
-  resolving_threads++;
-  assert(resolving_threads <= 1);
+  UTI_FdSetCloexec(inst->pipe[0]);
+  UTI_FdSetCloexec(inst->pipe[1]);
 
   if (pthread_create(&inst->thread, NULL, start_resolving, inst)) {
-    LOG_FATAL(LOGF_Nameserv, "pthread_create() failed");
+    LOG_FATAL("pthread_create() failed");
   }
 
-  SCH_AddInputFileHandler(inst->pipe[0], end_resolving, inst);
+  SCH_AddFileHandler(inst->pipe[0], SCH_FILE_INPUT, end_resolving, inst);
 }
 
 /* ================================================== */

ntp.h

@@ -38,23 +38,33 @@ typedef struct {
 
 typedef uint32_t NTP_int32;
 
+/* The UDP port number used by NTP */
+#define NTP_PORT 123
+
 /* The NTP protocol version that we support */
 #define NTP_VERSION 4
 
 /* Maximum stratum number (infinity) */
 #define NTP_MAX_STRATUM 16
 
-/* The minimum valid length of an extension field */
-#define NTP_MIN_EXTENSION_LENGTH 16
-
-/* The maximum assumed length of all extension fields in received
-   packets (RFC 5905 doesn't specify a limit on length or number of
-   extension fields in one packet) */
-#define NTP_MAX_EXTENSIONS_LENGTH 1024
+/* Invalid stratum number */
+#define NTP_INVALID_STRATUM 0
 
 /* The minimum and maximum supported length of MAC */
-#define NTP_MIN_MAC_LENGTH 16
-#define NTP_MAX_MAC_LENGTH MAX_HASH_LENGTH
+#define NTP_MIN_MAC_LENGTH (4 + 16)
+#define NTP_MAX_MAC_LENGTH (4 + MAX_HASH_LENGTH)
+
+/* The minimum valid length of an extension field */
+#define NTP_MIN_EF_LENGTH 16
+
+/* The maximum assumed length of all extension fields in an NTP packet,
+   including a MAC (RFC 5905 doesn't specify a limit on length or number of
+   extension fields in one packet) */
+#define NTP_MAX_EXTENSIONS_LENGTH (1024 + NTP_MAX_MAC_LENGTH)
+
+/* The maximum length of MAC in NTPv4 packets which allows deterministic
+   parsing of extension fields (RFC 7822) */
+#define NTP_MAX_V4_MAC_LENGTH (4 + 20)
 
 /* Type definition for leap bits */
 typedef enum {
@@ -86,21 +96,10 @@ typedef struct {
   NTP_int64 receive_ts;
   NTP_int64 transmit_ts;
 
-  /* Optional extension fields, we don't send packets with them yet */
-  /* uint8_t extensions[] */
-
-  /* Optional message authentication code (MAC) */
-  NTP_int32 auth_keyid;
-  uint8_t auth_data[NTP_MAX_MAC_LENGTH];
+  uint8_t extensions[NTP_MAX_EXTENSIONS_LENGTH];
 } NTP_Packet;
 
-#define NTP_NORMAL_PACKET_LENGTH (int)offsetof(NTP_Packet, auth_keyid)
-
-/* The buffer used to hold a datagram read from the network */
-typedef struct {
-  NTP_Packet ntp_pkt;
-  uint8_t extensions[NTP_MAX_EXTENSIONS_LENGTH];
-} NTP_Receive_Buffer;
+#define NTP_HEADER_LENGTH (int)offsetof(NTP_Packet, extensions)
 
 /* Macros to work with the lvm field */
 #define NTP_LVM_TO_LEAP(lvm) (((lvm) >> 6) & 0x3)
@@ -114,4 +113,45 @@ typedef struct {
 #define NTP_REFID_LOCAL 0x7F7F0101UL /* 127.127.1.1 */
 #define NTP_REFID_SMOOTH 0x7F7F01FFUL /* 127.127.1.255 */
 
+/* Enumeration for authentication modes of NTP packets */
+typedef enum {
+  NTP_AUTH_NONE = 0,            /* No authentication */
+  NTP_AUTH_SYMMETRIC,           /* MAC using symmetric key (RFC 1305, RFC 5905) */
+  NTP_AUTH_MSSNTP,              /* MS-SNTP authenticator field */
+  NTP_AUTH_MSSNTP_EXT,          /* MS-SNTP extended authenticator field */
+  NTP_AUTH_NTS,                 /* Network Time Security (RFC ????) */
+} NTP_AuthMode;
+
+/* Structure describing an NTP packet */
+typedef struct {
+  int length;
+  int version;
+  NTP_Mode mode;
+
+  int ext_fields;
+
+  struct {
+    NTP_AuthMode mode;
+    struct {
+      int start;
+      int length;
+      uint32_t key_id;
+    } mac;
+  } auth;
+} NTP_PacketInfo;
+
+/* Structure used to save NTP measurements.  time is the local time at which
+   the sample is to be considered to have been made and offset is the offset at
+   the time (positive indicates that the local clock is slow relative to the
+   source).  root_delay/root_dispersion include peer_delay/peer_dispersion. */
+typedef struct {
+  struct timespec time;
+  double offset;
+  double peer_delay;
+  double peer_dispersion;
+  double root_delay;
+  double root_dispersion;
+  int stratum;
+} NTP_Sample;
+
 #endif /* GOT_NTP_H */

ntp_auth.c

@@ -0,0 +1,500 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2019
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  NTP authentication
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "keys.h"
+#include "logging.h"
+#include "memory.h"
+#include "ntp_auth.h"
+#include "ntp_ext.h"
+#include "ntp_signd.h"
+#include "nts_ntp.h"
+#include "nts_ntp_client.h"
+#include "nts_ntp_server.h"
+#include "srcparams.h"
+#include "util.h"
+
+/* Structure to hold authentication configuration and state */
+
+struct NAU_Instance_Record {
+  NTP_AuthMode mode;            /* Authentication mode of NTP packets */
+  uint32_t key_id;              /* Identifier of a symmetric key */
+  NNC_Instance nts;             /* Client NTS state */
+};
+
+/* ================================================== */
+
+static int
+generate_symmetric_auth(uint32_t key_id, NTP_Packet *packet, NTP_PacketInfo *info)
+{
+  int auth_len, max_auth_len;
+
+  /* Truncate long MACs in NTPv4 packets to allow deterministic parsing
+     of extension fields (RFC 7822) */
+  max_auth_len = (info->version == 4 ? NTP_MAX_V4_MAC_LENGTH : NTP_MAX_MAC_LENGTH) - 4;
+  max_auth_len = MIN(max_auth_len, sizeof (NTP_Packet) - info->length - 4);
+
+  auth_len = KEY_GenerateAuth(key_id, (unsigned char *)packet, info->length,
+                              (unsigned char *)packet + info->length + 4, max_auth_len);
+  if (!auth_len) {
+    DEBUG_LOG("Could not generate auth data with key %"PRIu32, key_id);
+    return 0;
+  }
+
+  *(uint32_t *)((unsigned char *)packet + info->length) = htonl(key_id);
+  info->length += 4 + auth_len;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+check_symmetric_auth(NTP_Packet *packet, NTP_PacketInfo *info)
+{
+  int trunc_len;
+
+  if (info->auth.mac.length < NTP_MIN_MAC_LENGTH)
+    return 0;
+
+  trunc_len = info->version == 4 && info->auth.mac.length <= NTP_MAX_V4_MAC_LENGTH ?
+              NTP_MAX_V4_MAC_LENGTH : NTP_MAX_MAC_LENGTH;
+
+  if (!KEY_CheckAuth(info->auth.mac.key_id, (void *)packet, info->auth.mac.start,
+                     (unsigned char *)packet + info->auth.mac.start + 4,
+                     info->auth.mac.length - 4, trunc_len - 4))
+    return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static void
+adjust_timestamp(NTP_AuthMode mode, uint32_t key_id, struct timespec *ts)
+{
+  switch (mode) {
+    case NTP_AUTH_SYMMETRIC:
+      ts->tv_nsec += KEY_GetAuthDelay(key_id);
+      UTI_NormaliseTimespec(ts);
+      break;
+    case NTP_AUTH_MSSNTP:
+      ts->tv_nsec += NSD_GetAuthDelay(key_id);
+      UTI_NormaliseTimespec(ts);
+    default:
+      break;
+  }
+}
+
+/* ================================================== */
+
+static int
+is_zero_data(unsigned char *data, int length)
+{
+  int i;
+
+  for (i = 0; i < length; i++)
+    if (data[i])
+      return 0;
+  return 1;
+}
+
+/* ================================================== */
+
+static NAU_Instance
+create_instance(NTP_AuthMode mode)
+{
+  NAU_Instance instance;
+
+  instance = MallocNew(struct NAU_Instance_Record);
+  instance->mode = mode;
+  instance->key_id = INACTIVE_AUTHKEY;
+  instance->nts = NULL;
+
+  assert(sizeof (instance->key_id) == 4);
+
+  return instance;
+}
+
+/* ================================================== */
+
+NAU_Instance
+NAU_CreateNoneInstance(void)
+{
+  return create_instance(NTP_AUTH_NONE);
+}
+
+/* ================================================== */
+
+NAU_Instance
+NAU_CreateSymmetricInstance(uint32_t key_id)
+{
+  NAU_Instance instance = create_instance(NTP_AUTH_SYMMETRIC);
+
+  instance->key_id = key_id;
+
+  if (!KEY_KeyKnown(key_id))
+    LOG(LOGS_WARN, "Key %"PRIu32" is %s", key_id, "missing");
+  else if (!KEY_CheckKeyLength(key_id))
+    LOG(LOGS_WARN, "Key %"PRIu32" is %s", key_id, "too short");
+
+  return instance;
+}
+
+/* ================================================== */
+
+NAU_Instance
+NAU_CreateNtsInstance(IPSockAddr *nts_address, const char *name, const IPSockAddr *ntp_address)
+{
+  NAU_Instance instance = create_instance(NTP_AUTH_NTS);
+
+  instance->nts = NNC_CreateInstance(nts_address, name, ntp_address);
+
+  return instance;
+}
+
+/* ================================================== */
+
+void
+NAU_DestroyInstance(NAU_Instance instance)
+{
+  if (instance->nts)
+    NNC_DestroyInstance(instance->nts);
+  Free(instance);
+}
+
+/* ================================================== */
+
+int
+NAU_IsAuthEnabled(NAU_Instance instance)
+{
+  return instance->mode != NTP_AUTH_NONE;
+}
+
+/* ================================================== */
+
+int
+NAU_GetSuggestedNtpVersion(NAU_Instance instance)
+{
+  /* If the MAC in NTPv4 packets would be truncated, prefer NTPv3 for
+     compatibility with older chronyd servers */
+  if (instance->mode == NTP_AUTH_SYMMETRIC &&
+      KEY_GetAuthLength(instance->key_id) + sizeof (instance->key_id) > NTP_MAX_V4_MAC_LENGTH)
+    return 3;
+
+  return NTP_VERSION;
+}
+
+/* ================================================== */
+
+int
+NAU_PrepareRequestAuth(NAU_Instance instance)
+{
+  switch (instance->mode) {
+    case NTP_AUTH_NTS:
+      if (!NNC_PrepareForAuth(instance->nts))
+        return 0;
+      break;
+    default:
+      break;
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+void
+NAU_AdjustRequestTimestamp(NAU_Instance instance, struct timespec *ts)
+{
+  adjust_timestamp(instance->mode, instance->key_id, ts);
+}
+
+/* ================================================== */
+
+int
+NAU_GenerateRequestAuth(NAU_Instance instance, NTP_Packet *request, NTP_PacketInfo *info)
+{
+  switch (instance->mode) {
+    case NTP_AUTH_NONE:
+      break;
+    case NTP_AUTH_SYMMETRIC:
+      if (!generate_symmetric_auth(instance->key_id, request, info))
+        return 0;
+      break;
+    case NTP_AUTH_NTS:
+      if (!NNC_GenerateRequestAuth(instance->nts, request, info))
+        return 0;
+      break;
+    default:
+      assert(0);
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NAU_ParsePacket(NTP_Packet *packet, NTP_PacketInfo *info)
+{
+  int parsed, remainder, ef_length, ef_type;
+  unsigned char *data;
+
+  data = (void *)packet;
+  parsed = NTP_HEADER_LENGTH;
+  remainder = info->length - parsed;
+
+  info->ext_fields = 0;
+
+  /* Check if this is a plain NTP packet with no extension fields or MAC */
+  if (remainder <= 0)
+    return 1;
+
+  /* In NTPv3 and older packets don't have extension fields.  Anything after
+     the header is assumed to be a MAC. */
+  if (info->version <= 3) {
+    info->auth.mode = NTP_AUTH_SYMMETRIC;
+    info->auth.mac.start = parsed;
+    info->auth.mac.length = remainder;
+    info->auth.mac.key_id = ntohl(*(uint32_t *)(data + parsed));
+
+    /* Check if it is an MS-SNTP authenticator field or extended authenticator
+       field with zeroes as digest */
+    if (info->version == 3 && info->auth.mac.key_id) {
+      if (remainder == 20 && is_zero_data(data + parsed + 4, remainder - 4))
+        info->auth.mode = NTP_AUTH_MSSNTP;
+      else if (remainder == 72 && is_zero_data(data + parsed + 8, remainder - 8))
+        info->auth.mode = NTP_AUTH_MSSNTP_EXT;
+    }
+
+    return 1;
+  }
+
+  /* Check for a crypto NAK */
+  if (remainder == 4 && ntohl(*(uint32_t *)(data + parsed)) == 0) {
+    info->auth.mode = NTP_AUTH_SYMMETRIC;
+    info->auth.mac.start = parsed;
+    info->auth.mac.length = remainder;
+    info->auth.mac.key_id = 0;
+    return 1;
+  }
+
+  /* Parse the rest of the NTPv4 packet */
+
+  while (remainder > 0) {
+    /* Check if the remaining data is a MAC */
+    if (remainder >= NTP_MIN_MAC_LENGTH && remainder <= NTP_MAX_V4_MAC_LENGTH)
+      break;
+
+    /* The NTPv4-specific limit for MAC length enables deterministic parsing of
+       packets with extension fields (RFC 7822), but we support longer MACs in
+       packets with no extension fields for compatibility with older chrony
+       clients.  Check if the longer MAC would authenticate the packet before
+       trying to parse the data as an extension field. */
+    if (parsed == NTP_HEADER_LENGTH &&
+        remainder > NTP_MAX_V4_MAC_LENGTH && remainder <= NTP_MAX_MAC_LENGTH &&
+        KEY_CheckAuth(ntohl(*(uint32_t *)(data + parsed)), data, parsed,
+                      (void *)(data + parsed + 4), remainder - 4, NTP_MAX_MAC_LENGTH - 4))
+      break;
+
+    /* Check if this is a valid NTPv4 extension field and skip it */
+    if (!NEF_ParseField(packet, info->length, parsed, &ef_length, &ef_type, NULL, NULL)) {
+      /* Invalid MAC or format error */
+      DEBUG_LOG("Invalid format or MAC");
+      return 0;
+    }
+
+    assert(ef_length > 0);
+
+    switch (ef_type) {
+      case NTP_EF_NTS_UNIQUE_IDENTIFIER:
+      case NTP_EF_NTS_COOKIE:
+      case NTP_EF_NTS_COOKIE_PLACEHOLDER:
+      case NTP_EF_NTS_AUTH_AND_EEF:
+        info->auth.mode = NTP_AUTH_NTS;
+        break;
+      default:
+        DEBUG_LOG("Unknown extension field type=%x", (unsigned int)ef_type);
+    }
+
+    info->ext_fields++;
+    parsed += ef_length;
+    remainder = info->length - parsed;
+  }
+
+  if (remainder == 0) {
+    /* No MAC */
+    return 1;
+  } else if (remainder >= NTP_MIN_MAC_LENGTH) {
+    /* This is not 100% reliable as a MAC could fail to authenticate and could
+       pass as an extension field, leaving reminder smaller than the minimum MAC
+       length */
+    info->auth.mode = NTP_AUTH_SYMMETRIC;
+    info->auth.mac.start = parsed;
+    info->auth.mac.length = remainder;
+    info->auth.mac.key_id = ntohl(*(uint32_t *)(data + parsed));
+    return 1;
+  }
+
+  DEBUG_LOG("Invalid format");
+  return 0;
+}
+
+/* ================================================== */
+
+int
+NAU_CheckRequestAuth(NTP_Packet *request, NTP_PacketInfo *info, uint32_t *kod)
+{
+  *kod = 0;
+
+  switch (info->auth.mode) {
+    case NTP_AUTH_NONE:
+      break;
+    case NTP_AUTH_SYMMETRIC:
+      if (!check_symmetric_auth(request, info))
+        return 0;
+      break;
+    case NTP_AUTH_MSSNTP:
+      /* MS-SNTP requests are not authenticated */
+      break;
+    case NTP_AUTH_NTS:
+      if (!NNS_CheckRequestAuth(request, info, kod))
+        return 0;
+      break;
+    default:
+      return 0;
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+void
+NAU_AdjustResponseTimestamp(NTP_Packet *request, NTP_PacketInfo *info, struct timespec *ts)
+{
+  adjust_timestamp(info->auth.mode, info->auth.mac.key_id, ts);
+}
+
+/* ================================================== */
+
+int
+NAU_GenerateResponseAuth(NTP_Packet *request, NTP_PacketInfo *request_info,
+                         NTP_Packet *response, NTP_PacketInfo *response_info,
+                         NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr,
+                         uint32_t kod)
+{
+  switch (request_info->auth.mode) {
+    case NTP_AUTH_NONE:
+      break;
+    case NTP_AUTH_SYMMETRIC:
+      if (!generate_symmetric_auth(request_info->auth.mac.key_id, response, response_info))
+        return 0;
+      break;
+    case NTP_AUTH_MSSNTP:
+      /* Sign the packet asynchronously by ntp_signd */
+      if (!NSD_SignAndSendPacket(request_info->auth.mac.key_id, response, response_info,
+                                 remote_addr, local_addr))
+        return 0;
+      /* Don't send the original packet */
+      return 0;
+    case NTP_AUTH_NTS:
+      if (!NNS_GenerateResponseAuth(request, request_info, response, response_info, kod))
+        return 0;
+      break;
+    default:
+      DEBUG_LOG("Could not authenticate response auth_mode=%d", (int)request_info->auth.mode);
+      return 0;
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NAU_CheckResponseAuth(NAU_Instance instance, NTP_Packet *response, NTP_PacketInfo *info)
+{
+  /* The authentication must match the expected mode */
+  if (info->auth.mode != instance->mode)
+    return 0;
+
+  switch (info->auth.mode) {
+    case NTP_AUTH_NONE:
+      break;
+    case NTP_AUTH_SYMMETRIC:
+      /* Check if it is authenticated with the specified key */
+      if (info->auth.mac.key_id != instance->key_id)
+        return 0;
+      /* and that the MAC is valid */
+      if (!check_symmetric_auth(response, info))
+        return 0;
+      break;
+    case NTP_AUTH_NTS:
+      if (!NNC_CheckResponseAuth(instance->nts, response, info))
+        return 0;
+      break;
+    default:
+      return 0;
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+void
+NAU_ChangeAddress(NAU_Instance instance, IPAddr *address)
+{
+  switch (instance->mode) {
+    case NTP_AUTH_NONE:
+    case NTP_AUTH_SYMMETRIC:
+      break;
+    case NTP_AUTH_NTS:
+      NNC_ChangeAddress(instance->nts, address);
+      break;
+    default:
+      assert(0);
+  }
+}
+
+/* ================================================== */
+
+void
+NAU_DumpData(NAU_Instance instance)
+{
+  switch (instance->mode) {
+    case NTP_AUTH_NTS:
+      NNC_DumpData(instance->nts);
+      break;
+    default:
+      break;
+  }
+}

ntp_auth.h

@@ -0,0 +1,92 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2019
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for NTP authentication
+  */
+
+#ifndef GOT_NTP_AUTH_H
+#define GOT_NTP_AUTH_H
+
+#include "addressing.h"
+#include "ntp.h"
+
+typedef struct NAU_Instance_Record *NAU_Instance;
+
+/* Create an authenticator instance in a specific mode */
+extern NAU_Instance NAU_CreateNoneInstance(void);
+extern NAU_Instance NAU_CreateSymmetricInstance(uint32_t key_id);
+extern NAU_Instance NAU_CreateNtsInstance(IPSockAddr *nts_address, const char *name,
+                                          const IPSockAddr *ntp_address);
+
+/* Destroy an instance */
+extern void NAU_DestroyInstance(NAU_Instance instance);
+
+/* Check if an instance is not in the None mode */
+extern int NAU_IsAuthEnabled(NAU_Instance instance);
+
+/* Get NTP version recommended for better compatibility */
+extern int NAU_GetSuggestedNtpVersion(NAU_Instance instance);
+
+/* Perform operations necessary for NAU_GenerateRequestAuth() */
+extern int NAU_PrepareRequestAuth(NAU_Instance instance);
+
+/* Adjust a transmit timestamp for an estimated minimum time it takes to call
+   NAU_GenerateRequestAuth() */
+extern void NAU_AdjustRequestTimestamp(NAU_Instance instance, struct timespec *ts);
+
+/* Extend a request with data required by the authentication mode */
+extern int NAU_GenerateRequestAuth(NAU_Instance instance, NTP_Packet *request,
+                                   NTP_PacketInfo *info);
+
+/* Parse a request or response to detect the authentication mode */
+extern int NAU_ParsePacket(NTP_Packet *packet, NTP_PacketInfo *info);
+
+/* Verify that a request is authentic.  If it is not authentic and a non-zero
+   kod code is returned, a KoD response should be sent back. */
+extern int NAU_CheckRequestAuth(NTP_Packet *request, NTP_PacketInfo *info, uint32_t *kod);
+
+/* Adjust a transmit timestamp for an estimated minimum time it takes to call
+   NAU_GenerateResponseAuth() */
+extern void NAU_AdjustResponseTimestamp(NTP_Packet *request, NTP_PacketInfo *info,
+                                        struct timespec *ts);
+
+/* Extend a response with data required by the authentication mode.  This
+   function can be called only if the previous call of NAU_CheckRequestAuth()
+   was on the same request. */
+extern int NAU_GenerateResponseAuth(NTP_Packet *request, NTP_PacketInfo *request_info,
+                                    NTP_Packet *response, NTP_PacketInfo *response_info,
+                                    NTP_Remote_Address *remote_addr,
+                                    NTP_Local_Address *local_addr,
+                                    uint32_t kod);
+
+/* Verify that a response is authentic */
+extern int NAU_CheckResponseAuth(NAU_Instance instance, NTP_Packet *response,
+                                 NTP_PacketInfo *info);
+
+/* Change an authentication-specific address (e.g. after replacing a source) */
+extern void NAU_ChangeAddress(NAU_Instance instance, IPAddr *address);
+
+/* Save authentication-specific data to speed up the next start */
+extern void NAU_DumpData(NAU_Instance instance);
+
+#endif

ntp_core.h

@@ -38,6 +38,18 @@ typedef enum {
   NTP_SERVER, NTP_PEER
 } NTP_Source_Type;
 
+typedef enum {
+  NTP_TS_DAEMON = 0,
+  NTP_TS_KERNEL,
+  NTP_TS_HARDWARE
+} NTP_Timestamp_Source;
+
+typedef struct {
+  struct timespec ts;
+  double err;
+  NTP_Timestamp_Source source;
+} NTP_Local_Timestamp;
+
 /* This is a private data type used for storing the instance record for
    each source that we are chiming with */
 typedef struct NCR_Instance_Record *NCR_Instance;
@@ -47,7 +59,8 @@ extern void NCR_Initialise(void);
 extern void NCR_Finalise(void);
 
 /* Get a new instance for a server or peer */
-extern NCR_Instance NCR_GetInstance(NTP_Remote_Address *remote_addr, NTP_Source_Type type, SourceParameters *params);
+extern NCR_Instance NCR_CreateInstance(NTP_Remote_Address *remote_addr, NTP_Source_Type type,
+                                       SourceParameters *params, const char *name);
 
 /* Destroy an instance */
 extern void NCR_DestroyInstance(NCR_Instance instance);
@@ -58,26 +71,39 @@ extern void NCR_StartInstance(NCR_Instance instance);
 /* Reset an instance */
 extern void NCR_ResetInstance(NCR_Instance inst);
 
+/* Reset polling interval of an instance */
+extern void NCR_ResetPoll(NCR_Instance instance);
+
 /* Change the remote address of an instance */
-extern void NCR_ChangeRemoteAddress(NCR_Instance inst, NTP_Remote_Address *remote_addr);
+extern void NCR_ChangeRemoteAddress(NCR_Instance inst, NTP_Remote_Address *remote_addr,
+                                    int ntp_only);
 
 /* This routine is called when a new packet arrives off the network,
    and it relates to a source we have an ongoing protocol exchange with */
-extern int NCR_ProcessKnown(NTP_Packet *message, struct timeval *now, double now_err, NCR_Instance data, NTP_Local_Address *local_addr, int length);
+extern int NCR_ProcessRxKnown(NCR_Instance inst, NTP_Local_Address *local_addr,
+                              NTP_Local_Timestamp *rx_ts, NTP_Packet *message, int length);
 
 /* This routine is called when a new packet arrives off the network,
    and we do not recognize its source */
-extern void NCR_ProcessUnknown(NTP_Packet *message, struct timeval *now, double now_err, NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr, int length);
+extern void NCR_ProcessRxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr,
+                                 NTP_Local_Timestamp *rx_ts, NTP_Packet *message, int length);
+
+/* This routine is called when a packet is sent to a source we have
+   an ongoing protocol exchange with */
+extern void NCR_ProcessTxKnown(NCR_Instance inst, NTP_Local_Address *local_addr,
+                               NTP_Local_Timestamp *tx_ts, NTP_Packet *message, int length);
+
+/* This routine is called when a packet is sent to a destination we
+   do not recognize */
+extern void NCR_ProcessTxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr,
+                                 NTP_Local_Timestamp *tx_ts, NTP_Packet *message, int length);
 
 /* Slew receive and transmit times in instance records */
-extern void NCR_SlewTimes(NCR_Instance inst, struct timeval *when, double dfreq, double doffset);
+extern void NCR_SlewTimes(NCR_Instance inst, struct timespec *when, double dfreq, double doffset);
 
-/* Take a particular source online (i.e. start sampling it) */
-extern void NCR_TakeSourceOnline(NCR_Instance inst);
-
-/* Take a particular source offline (i.e. stop sampling it, without
-   marking it unreachable in the source selection stuff) */
-extern void NCR_TakeSourceOffline(NCR_Instance inst);
+/* Take a particular source online (i.e. start sampling it) or offline
+   (i.e. stop sampling it) */
+extern void NCR_SetConnectivity(NCR_Instance inst, SRC_Connectivity connectivity);
 
 extern void NCR_ModifyMinpoll(NCR_Instance inst, int new_minpoll);
 
@@ -95,7 +121,8 @@ extern void NCR_ModifyPolltarget(NCR_Instance inst, int new_poll_target);
 
 extern void NCR_InitiateSampleBurst(NCR_Instance inst, int n_good_samples, int n_total_samples);
 
-extern void NCR_ReportSource(NCR_Instance inst, RPT_SourceReport *report, struct timeval *now);
+extern void NCR_ReportSource(NCR_Instance inst, RPT_SourceReport *report, struct timespec *now);
+extern void NCR_GetNTPReport(NCR_Instance inst, RPT_NTPReport *report);
 
 extern int NCR_AddAccessRestriction(IPAddr *ip_addr, int subnet_bits, int allow, int all);
 extern int NCR_CheckAccessRestriction(IPAddr *ip_addr);
@@ -105,8 +132,12 @@ extern void NCR_IncrementActivityCounters(NCR_Instance inst, int *online, int *o
 
 extern NTP_Remote_Address *NCR_GetRemoteAddress(NCR_Instance instance);
 
+extern uint32_t NCR_GetLocalRefid(NCR_Instance inst);
+
 extern int NCR_IsSyncPeer(NCR_Instance instance);
 
+extern void NCR_DumpAuthData(NCR_Instance inst);
+
 extern void NCR_AddBroadcastDestination(IPAddr *addr, unsigned short port, int interval);
 
 #endif /* GOT_NTP_CORE_H */

ntp_ext.c

@@ -0,0 +1,192 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2019
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Functions for adding and parsing NTPv4 extension fields
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "ntp_ext.h"
+
+struct ExtFieldHeader {
+  uint16_t type;
+  uint16_t length;
+};
+
+/* ================================================== */
+
+static int
+format_field(unsigned char *buffer, int buffer_length, int start,
+             int type, int body_length, int *length, void **body)
+{
+  struct ExtFieldHeader *header;
+
+  if (buffer_length < 0 || start < 0 || buffer_length <= start ||
+      buffer_length - start < sizeof (*header) || start % 4 != 0)
+    return 0;
+
+  header = (struct ExtFieldHeader *)(buffer + start);
+
+  if (body_length < 0 || sizeof (*header) + body_length > 0xffff ||
+      start + sizeof (*header) + body_length > buffer_length || body_length % 4 != 0)
+    return 0;
+
+  header->type = htons(type);
+  header->length = htons(sizeof (*header) + body_length);
+  *length = sizeof (*header) + body_length;
+  *body = header + 1;
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NEF_SetField(unsigned char *buffer, int buffer_length, int start,
+             int type, void *body, int body_length, int *length)
+{
+  void *ef_body;
+
+  if (!format_field(buffer, buffer_length, start, type, body_length, length, &ef_body))
+    return 0;
+
+  memcpy(ef_body, body, body_length);
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NEF_AddBlankField(NTP_Packet *packet, NTP_PacketInfo *info, int type, int body_length, void **body)
+{
+  int ef_length, length = info->length;
+
+  if (length < NTP_HEADER_LENGTH || length >= sizeof (*packet) || length % 4 != 0)
+    return 0;
+
+  /* Only NTPv4 packets can have extension fields */
+  if (info->version != 4)
+    return 0;
+
+  if (!format_field((unsigned char *)packet, sizeof (*packet), length,
+                    type, body_length, &ef_length, body))
+    return 0;
+
+  if (ef_length < NTP_MIN_EF_LENGTH)
+    return 0;
+
+  info->length += ef_length;
+  info->ext_fields++;
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NEF_AddField(NTP_Packet *packet, NTP_PacketInfo *info,
+             int type, void *body, int body_length)
+{
+  void *ef_body;
+
+  if (!NEF_AddBlankField(packet, info, type, body_length, &ef_body))
+    return 0;
+
+  memcpy(ef_body, body, body_length);
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NEF_ParseSingleField(unsigned char *buffer, int buffer_length, int start,
+                     int *length, int *type, void **body, int *body_length)
+{
+  struct ExtFieldHeader *header;
+  int ef_length;
+
+  if (buffer_length < 0 || start < 0 || buffer_length <= start ||
+      buffer_length - start < sizeof (*header))
+    return 0;
+
+  header = (struct ExtFieldHeader *)(buffer + start);
+
+  assert(sizeof (*header) == 4);
+
+  ef_length = ntohs(header->length);
+
+  if (ef_length < (int)(sizeof (*header)) || start + ef_length > buffer_length ||
+      ef_length % 4 != 0)
+    return 0;
+
+  if (length)
+    *length = ef_length;
+  if (type)
+    *type = ntohs(header->type);
+  if (body)
+    *body = header + 1;
+  if (body_length)
+    *body_length = ef_length - sizeof (*header);
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NEF_ParseField(NTP_Packet *packet, int packet_length, int start,
+               int *length, int *type, void **body, int *body_length)
+{
+  int ef_length;
+
+  if (packet_length <= NTP_HEADER_LENGTH || packet_length > sizeof (*packet) ||
+      packet_length <= start || packet_length % 4 != 0 ||
+      start < NTP_HEADER_LENGTH || start % 4 != 0)
+    return 0;
+
+  /* Only NTPv4 packets have extension fields */
+  if (NTP_LVM_TO_VERSION(packet->lvm) != 4)
+    return 0;
+
+  /* Check if the remaining data is a MAC.  RFC 7822 specifies the maximum
+     length of a MAC in NTPv4 packets in order to enable deterministic
+     parsing. */
+  if (packet_length - start <= NTP_MAX_V4_MAC_LENGTH)
+    return 0;
+
+  if (!NEF_ParseSingleField((unsigned char *)packet, packet_length, start,
+                            &ef_length, type, body, body_length))
+    return 0;
+
+  if (ef_length < NTP_MIN_EF_LENGTH)
+    return 0;
+
+  if (length)
+    *length = ef_length;
+
+  return 1;
+}

ntp_ext.h

@@ -0,0 +1,43 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2019
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for NTP extension fields
+  */
+
+#ifndef GOT_NTP_EXT_H
+#define GOT_NTP_EXT_H
+
+#include "ntp.h"
+
+extern int NEF_SetField(unsigned char *buffer, int buffer_length, int start,
+                        int type, void *body, int body_length, int *length);
+extern int NEF_AddBlankField(NTP_Packet *packet, NTP_PacketInfo *info, int type,
+                             int body_length, void **body);
+extern int NEF_AddField(NTP_Packet *packet, NTP_PacketInfo *info,
+                        int type, void *body, int body_length);
+extern int NEF_ParseSingleField(unsigned char *buffer, int buffer_length, int start,
+                                int *length, int *type, void **body, int *body_length);
+extern int NEF_ParseField(NTP_Packet *packet, int packet_length, int start,
+                          int *length, int *type, void **body, int *body_length);
+
+#endif

ntp_io.c

@@ -4,7 +4,7 @@
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
  * Copyright (C) Timo Teras  2009
- * Copyright (C) Miroslav Lichvar  2009, 2013-2015
+ * Copyright (C) Miroslav Lichvar  2009, 2013-2016, 2018
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -34,34 +34,28 @@
 #include "ntp_core.h"
 #include "ntp_sources.h"
 #include "sched.h"
+#include "socket.h"
 #include "local.h"
 #include "logging.h"
 #include "conf.h"
+#include "privops.h"
 #include "util.h"
 
+#ifdef HAVE_LINUX_TIMESTAMPING
+#include "ntp_io_linux.h"
+#endif
+
 #define INVALID_SOCK_FD -1
 
-union sockaddr_in46 {
-  struct sockaddr_in in4;
-#ifdef FEAT_IPV6
-  struct sockaddr_in6 in6;
-#endif
-  struct sockaddr u;
-};
-
 /* The server/peer and client sockets for IPv4 and IPv6 */
 static int server_sock_fd4;
-static int client_sock_fd4;
-#ifdef FEAT_IPV6
 static int server_sock_fd6;
+static int client_sock_fd4;
 static int client_sock_fd6;
-#endif
 
 /* Reference counters for server sockets to keep them open only when needed */
 static int server_sock_ref4;
-#ifdef FEAT_IPV6
 static int server_sock_ref6;
-#endif
 
 /* Flag indicating we create a new connected client socket for each
    server instead of sharing client_sock_fd4 and client_sock_fd6 */
@@ -73,161 +67,61 @@ static int separate_client_sockets;
    disabled */
 static int permanent_server_sockets;
 
+/* Flag indicating the server IPv4 socket is bound to an address */
+static int bound_server_sock_fd4;
+
 /* Flag indicating that we have been initialised */
 static int initialised=0;
 
 /* ================================================== */
 
 /* Forward prototypes */
-static void read_from_socket(void *anything);
+static void read_from_socket(int sock_fd, int event, void *anything);
 
 /* ================================================== */
 
 static int
-prepare_socket(int family, int port_number, int client_only)
+open_socket(int family, int local_port, int client_only, IPSockAddr *remote_addr)
 {
-  union sockaddr_in46 my_addr;
-  socklen_t my_addr_len;
-  int sock_fd;
-  IPAddr bind_address;
-  int on_off = 1;
-  
-  /* Open Internet domain UDP socket for NTP message transmissions */
+  int sock_fd, sock_flags, events = SCH_FILE_INPUT;
+  IPSockAddr local_addr;
 
-  sock_fd = socket(family, SOCK_DGRAM, 0);
+  if (!SCK_IsFamilySupported(family))
+    return INVALID_SOCK_FD;
 
+  if (!client_only)
+    CNF_GetBindAddress(family, &local_addr.ip_addr);
+  else
+    CNF_GetBindAcquisitionAddress(family, &local_addr.ip_addr);
+
+  if (local_addr.ip_addr.family != family)
+    SCK_GetAnyLocalIPAddress(family, &local_addr.ip_addr);
+
+  local_addr.port = local_port;
+
+  sock_flags = SCK_FLAG_RX_DEST_ADDR | SCK_FLAG_PRIV_BIND;
+  if (!client_only)
+    sock_flags |= SCK_FLAG_BROADCAST;
+
+  sock_fd = SCK_OpenUdpSocket(remote_addr, &local_addr, sock_flags);
   if (sock_fd < 0) {
-    if (!client_only) {
-      LOG(LOGS_ERR, LOGF_NtpIO, "Could not open %s NTP socket : %s",
-          UTI_SockaddrFamilyToString(family), strerror(errno));
-    } else {
-      DEBUG_LOG(LOGF_NtpIO, "Could not open %s NTP socket : %s",
-                UTI_SockaddrFamilyToString(family), strerror(errno));
-    }
+    if (!client_only)
+      LOG(LOGS_ERR, "Could not open NTP socket on %s", UTI_IPSockAddrToString(&local_addr));
     return INVALID_SOCK_FD;
   }
 
-  /* Close on exec */
-  UTI_FdSetCloexec(sock_fd);
+  if (!client_only && family == IPADDR_INET4 && local_addr.port > 0)
+    bound_server_sock_fd4 = local_addr.ip_addr.addr.in4 != INADDR_ANY;
 
-  /* Prepare local address */
-  memset(&my_addr, 0, sizeof (my_addr));
-  my_addr_len = 0;
-
-  switch (family) {
-    case AF_INET:
-      if (!client_only)
-        CNF_GetBindAddress(IPADDR_INET4, &bind_address);
-      else
-        CNF_GetBindAcquisitionAddress(IPADDR_INET4, &bind_address);
-
-      if (bind_address.family == IPADDR_INET4)
-        my_addr.in4.sin_addr.s_addr = htonl(bind_address.addr.in4);
-      else if (port_number)
-        my_addr.in4.sin_addr.s_addr = htonl(INADDR_ANY);
-      else
-        break;
-
-      my_addr.in4.sin_family = family;
-      my_addr.in4.sin_port = htons(port_number);
-      my_addr_len = sizeof (my_addr.in4);
-
-      break;
-#ifdef FEAT_IPV6
-    case AF_INET6:
-      if (!client_only)
-        CNF_GetBindAddress(IPADDR_INET6, &bind_address);
-      else
-        CNF_GetBindAcquisitionAddress(IPADDR_INET6, &bind_address);
-
-      if (bind_address.family == IPADDR_INET6)
-        memcpy(my_addr.in6.sin6_addr.s6_addr, bind_address.addr.in6,
-            sizeof (my_addr.in6.sin6_addr.s6_addr));
-      else if (port_number)
-        my_addr.in6.sin6_addr = in6addr_any;
-      else
-        break;
-
-      my_addr.in6.sin6_family = family;
-      my_addr.in6.sin6_port = htons(port_number);
-      my_addr_len = sizeof (my_addr.in6);
-
-      break;
+  /* Enable kernel/HW timestamping of packets */
+#ifdef HAVE_LINUX_TIMESTAMPING
+  if (!NIO_Linux_SetTimestampSocketOptions(sock_fd, client_only, &events))
 #endif
-    default:
-      assert(0);
-  }
+    if (!SCK_EnableKernelRxTimestamping(sock_fd))
+      ;
 
-  /* Make the socket capable of re-using an old address if binding to a specific port */
-  if (port_number &&
-      setsockopt(sock_fd, SOL_SOCKET, SO_REUSEADDR, (char *)&on_off, sizeof(on_off)) < 0) {
-    LOG(LOGS_ERR, LOGF_NtpIO, "Could not set reuseaddr socket options");
-    /* Don't quit - we might survive anyway */
-  }
-  
-  /* Make the socket capable of sending broadcast pkts - needed for NTP broadcast mode */
-  if (!client_only &&
-      setsockopt(sock_fd, SOL_SOCKET, SO_BROADCAST, (char *)&on_off, sizeof(on_off)) < 0) {
-    LOG(LOGS_ERR, LOGF_NtpIO, "Could not set broadcast socket options");
-    /* Don't quit - we might survive anyway */
-  }
-
-#ifdef SO_TIMESTAMP
-  /* Enable receiving of timestamp control messages */
-  if (setsockopt(sock_fd, SOL_SOCKET, SO_TIMESTAMP, (char *)&on_off, sizeof(on_off)) < 0) {
-    LOG(LOGS_ERR, LOGF_NtpIO, "Could not set timestamp socket options");
-    /* Don't quit - we might survive anyway */
-  }
-#endif
-
-#ifdef IP_FREEBIND
-  /* Allow binding to address that doesn't exist yet */
-  if (my_addr_len > 0 &&
-      setsockopt(sock_fd, IPPROTO_IP, IP_FREEBIND, (char *)&on_off, sizeof(on_off)) < 0) {
-    LOG(LOGS_ERR, LOGF_NtpIO, "Could not set free bind socket option");
-  }
-#endif
-
-  if (family == AF_INET) {
-#ifdef IP_PKTINFO
-    /* We want the local IP info on server sockets */
-    if (setsockopt(sock_fd, IPPROTO_IP, IP_PKTINFO, (char *)&on_off, sizeof(on_off)) < 0) {
-      LOG(LOGS_ERR, LOGF_NtpIO, "Could not set packet info socket option");
-      /* Don't quit - we might survive anyway */
-    }
-#endif
-  }
-#ifdef FEAT_IPV6
-  else if (family == AF_INET6) {
-#ifdef IPV6_V6ONLY
-    /* Receive IPv6 packets only */
-    if (setsockopt(sock_fd, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&on_off, sizeof(on_off)) < 0) {
-      LOG(LOGS_ERR, LOGF_NtpIO, "Could not set IPV6_V6ONLY socket option");
-    }
-#endif
-
-#ifdef IPV6_RECVPKTINFO
-    if (setsockopt(sock_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, (char *)&on_off, sizeof(on_off)) < 0) {
-      LOG(LOGS_ERR, LOGF_NtpIO, "Could not set IPv6 packet info socket option");
-    }
-#elif defined(IPV6_PKTINFO)
-    if (setsockopt(sock_fd, IPPROTO_IPV6, IPV6_PKTINFO, (char *)&on_off, sizeof(on_off)) < 0) {
-      LOG(LOGS_ERR, LOGF_NtpIO, "Could not set IPv6 packet info socket option");
-    }
-#endif
-  }
-#endif
-
-  /* Bind the socket if a port or address was specified */
-  if (my_addr_len > 0 && bind(sock_fd, &my_addr.u, my_addr_len) < 0) {
-    LOG(LOGS_ERR, LOGF_NtpIO, "Could not bind %s NTP socket : %s",
-        UTI_SockaddrFamilyToString(family), strerror(errno));
-    close(sock_fd);
-    return INVALID_SOCK_FD;
-  }
-
-  /* Register handler for read events on the socket */
-  SCH_AddInputFileHandler(sock_fd, read_from_socket, (void *)(long)sock_fd);
+  /* Register handler for read and possibly exception events on the socket */
+  SCH_AddFileHandler(sock_fd, events, read_from_socket, NULL);
 
   return sock_fd;
 }
@@ -235,40 +129,9 @@ prepare_socket(int family, int port_number, int client_only)
 /* ================================================== */
 
 static int
-prepare_separate_client_socket(int family)
+open_separate_client_socket(IPSockAddr *remote_addr)
 {
-  switch (family) {
-    case IPADDR_INET4:
-      return prepare_socket(AF_INET, 0, 1);
-#ifdef FEAT_IPV6
-    case IPADDR_INET6:
-      return prepare_socket(AF_INET6, 0, 1);
-#endif
-    default:
-      return INVALID_SOCK_FD;
-  }
-}
-
-/* ================================================== */
-
-static int
-connect_socket(int sock_fd, NTP_Remote_Address *remote_addr)
-{
-  union sockaddr_in46 addr;
-  socklen_t addr_len;
-
-  addr_len = UTI_IPAndPortToSockaddr(&remote_addr->ip_addr, remote_addr->port, &addr.u);
-
-  assert(addr_len);
-
-  if (connect(sock_fd, &addr.u, addr_len) < 0) {
-    DEBUG_LOG(LOGF_NtpIO, "Could not connect NTP socket to %s:%d : %s",
-        UTI_IPToString(&remote_addr->ip_addr), remote_addr->port,
-        strerror(errno));
-    return 0;
-  }
-
-  return 1;
+  return open_socket(remote_addr->ip_addr.family, 0, 1, remote_addr);
 }
 
 /* ================================================== */
@@ -279,11 +142,15 @@ close_socket(int sock_fd)
   if (sock_fd == INVALID_SOCK_FD)
     return;
 
-  SCH_RemoveInputFileHandler(sock_fd);
-  close(sock_fd);
+#ifdef HAVE_LINUX_TIMESTAMPING
+  NIO_Linux_NotifySocketClosing(sock_fd);
+#endif
+  SCH_RemoveFileHandler(sock_fd);
+  SCK_CloseSocket(sock_fd);
 }
 
 /* ================================================== */
+
 void
 NIO_Initialise(int family)
 {
@@ -292,6 +159,20 @@ NIO_Initialise(int family)
   assert(!initialised);
   initialised = 1;
 
+#ifdef PRIVOPS_BINDSOCKET
+  SCK_SetPrivBind(PRV_BindSocket);
+#endif
+
+#ifdef HAVE_LINUX_TIMESTAMPING
+  NIO_Linux_Initialise();
+#else
+  if (1) {
+    CNF_HwTsInterface *conf_iface;
+    if (CNF_GetHwTsInterface(0, &conf_iface))
+      LOG_FATAL("HW timestamping not supported");
+  }
+#endif
+
   server_port = CNF_GetNTPPort();
   client_port = CNF_GetAcquisitionPort();
 
@@ -304,48 +185,39 @@ NIO_Initialise(int family)
                                               client_port == server_port);
 
   server_sock_fd4 = INVALID_SOCK_FD;
-  client_sock_fd4 = INVALID_SOCK_FD;
-  server_sock_ref4 = 0;
-#ifdef FEAT_IPV6
   server_sock_fd6 = INVALID_SOCK_FD;
+  client_sock_fd4 = INVALID_SOCK_FD;
   client_sock_fd6 = INVALID_SOCK_FD;
+  server_sock_ref4 = 0;
   server_sock_ref6 = 0;
-#endif
 
   if (family == IPADDR_UNSPEC || family == IPADDR_INET4) {
     if (permanent_server_sockets && server_port)
-      server_sock_fd4 = prepare_socket(AF_INET, server_port, 0);
+      server_sock_fd4 = open_socket(IPADDR_INET4, server_port, 0, NULL);
     if (!separate_client_sockets) {
       if (client_port != server_port || !server_port)
-        client_sock_fd4 = prepare_socket(AF_INET, client_port, 1);
+        client_sock_fd4 = open_socket(IPADDR_INET4, client_port, 1, NULL);
       else
         client_sock_fd4 = server_sock_fd4;
     }
   }
-#ifdef FEAT_IPV6
+
   if (family == IPADDR_UNSPEC || family == IPADDR_INET6) {
     if (permanent_server_sockets && server_port)
-      server_sock_fd6 = prepare_socket(AF_INET6, server_port, 0);
+      server_sock_fd6 = open_socket(IPADDR_INET6, server_port, 0, NULL);
     if (!separate_client_sockets) {
       if (client_port != server_port || !server_port)
-        client_sock_fd6 = prepare_socket(AF_INET6, client_port, 1);
+        client_sock_fd6 = open_socket(IPADDR_INET6, client_port, 1, NULL);
       else
         client_sock_fd6 = server_sock_fd6;
     }
   }
-#endif
 
-  if ((server_port && server_sock_fd4 == INVALID_SOCK_FD &&
-       permanent_server_sockets 
-#ifdef FEAT_IPV6
-       && server_sock_fd6 == INVALID_SOCK_FD
-#endif
-      ) || (!separate_client_sockets && client_sock_fd4 == INVALID_SOCK_FD
-#ifdef FEAT_IPV6
-       && client_sock_fd6 == INVALID_SOCK_FD
-#endif
-      )) {
-    LOG_FATAL(LOGF_NtpIO, "Could not open NTP sockets");
+  if ((server_port && permanent_server_sockets &&
+       server_sock_fd4 == INVALID_SOCK_FD && server_sock_fd6 == INVALID_SOCK_FD) ||
+      (!separate_client_sockets &&
+       client_sock_fd4 == INVALID_SOCK_FD && client_sock_fd6 == INVALID_SOCK_FD)) {
+    LOG_FATAL("Could not open NTP sockets");
   }
 }
 
@@ -358,12 +230,16 @@ NIO_Finalise(void)
     close_socket(client_sock_fd4);
   close_socket(server_sock_fd4);
   server_sock_fd4 = client_sock_fd4 = INVALID_SOCK_FD;
-#ifdef FEAT_IPV6
+
   if (server_sock_fd6 != client_sock_fd6)
     close_socket(client_sock_fd6);
   close_socket(server_sock_fd6);
   server_sock_fd6 = client_sock_fd6 = INVALID_SOCK_FD;
+
+#ifdef HAVE_LINUX_TIMESTAMPING
+  NIO_Linux_Finalise();
 #endif
+
   initialised = 0;
 }
 
@@ -373,25 +249,13 @@ int
 NIO_OpenClientSocket(NTP_Remote_Address *remote_addr)
 {
   if (separate_client_sockets) {
-    int sock_fd = prepare_separate_client_socket(remote_addr->ip_addr.family);
-
-    if (sock_fd == INVALID_SOCK_FD)
-      return INVALID_SOCK_FD;
-
-    if (!connect_socket(sock_fd, remote_addr)) {
-      close_socket(sock_fd);
-      return INVALID_SOCK_FD;
-    }
-
-    return sock_fd;
+    return open_separate_client_socket(remote_addr);
   } else {
     switch (remote_addr->ip_addr.family) {
       case IPADDR_INET4:
         return client_sock_fd4;
-#ifdef FEAT_IPV6
       case IPADDR_INET6:
         return client_sock_fd6;
-#endif
       default:
         return INVALID_SOCK_FD;
     }
@@ -408,20 +272,18 @@ NIO_OpenServerSocket(NTP_Remote_Address *remote_addr)
       if (permanent_server_sockets)
         return server_sock_fd4;
       if (server_sock_fd4 == INVALID_SOCK_FD)
-        server_sock_fd4 = prepare_socket(AF_INET, CNF_GetNTPPort(), 0);
+        server_sock_fd4 = open_socket(IPADDR_INET4, CNF_GetNTPPort(), 0, NULL);
       if (server_sock_fd4 != INVALID_SOCK_FD)
         server_sock_ref4++;
       return server_sock_fd4;
-#ifdef FEAT_IPV6
     case IPADDR_INET6:
       if (permanent_server_sockets)
         return server_sock_fd6;
       if (server_sock_fd6 == INVALID_SOCK_FD)
-        server_sock_fd6 = prepare_socket(AF_INET6, CNF_GetNTPPort(), 0);
+        server_sock_fd6 = open_socket(IPADDR_INET6, CNF_GetNTPPort(), 0, NULL);
       if (server_sock_fd6 != INVALID_SOCK_FD)
         server_sock_ref6++;
       return server_sock_fd6;
-#endif
     default:
       return INVALID_SOCK_FD;
   }
@@ -449,16 +311,12 @@ NIO_CloseServerSocket(int sock_fd)
       close_socket(server_sock_fd4);
       server_sock_fd4 = INVALID_SOCK_FD;
     }
-  }
-#ifdef FEAT_IPV6
-  else if (sock_fd == server_sock_fd6) {
+  } else if (sock_fd == server_sock_fd6) {
     if (--server_sock_ref6 <= 0) {
       close_socket(server_sock_fd6);
       server_sock_fd6 = INVALID_SOCK_FD;
     }
-  }
-#endif
-  else {
+  } else {
     assert(0);
   }
 }
@@ -469,228 +327,151 @@ int
 NIO_IsServerSocket(int sock_fd)
 {
   return sock_fd != INVALID_SOCK_FD &&
-    (sock_fd == server_sock_fd4
-#ifdef FEAT_IPV6
-     || sock_fd == server_sock_fd6
-#endif
-    );
+    (sock_fd == server_sock_fd4 || sock_fd == server_sock_fd6);
 }
 
 /* ================================================== */
 
-static void
-read_from_socket(void *anything)
+int
+NIO_IsServerSocketOpen(void)
 {
-  /* This should only be called when there is something
-     to read, otherwise it will block. */
-
-  int status, sock_fd;
-  NTP_Receive_Buffer message;
-  union sockaddr_in46 where_from;
-  unsigned int flags = 0;
-  struct timeval now;
-  double now_err;
-  NTP_Remote_Address remote_addr;
-  NTP_Local_Address local_addr;
-  char cmsgbuf[256];
-  struct msghdr msg;
-  struct iovec iov;
-  struct cmsghdr *cmsg;
-
-  assert(initialised);
-
-  SCH_GetLastEventTime(&now, &now_err, NULL);
-
-  iov.iov_base = &message.ntp_pkt;
-  iov.iov_len = sizeof(message);
-  msg.msg_name = &where_from;
-  msg.msg_namelen = sizeof(where_from);
-  msg.msg_iov = &iov;
-  msg.msg_iovlen = 1;
-  msg.msg_control = (void *) cmsgbuf;
-  msg.msg_controllen = sizeof(cmsgbuf);
-  msg.msg_flags = 0;
-
-  sock_fd = (long)anything;
-  status = recvmsg(sock_fd, &msg, flags);
-
-  /* Don't bother checking if read failed or why if it did.  More
-     likely than not, it will be connection refused, resulting from a
-     previous sendto() directing a datagram at a port that is not
-     listening (which appears to generate an ICMP response, and on
-     some architectures e.g. Linux this is translated into an error
-     reponse on a subsequent recvfrom). */
-
-  if (status > 0) {
-    if (msg.msg_namelen > sizeof (where_from))
-      LOG_FATAL(LOGF_NtpIO, "Truncated source address");
-
-    UTI_SockaddrToIPAndPort(&where_from.u, &remote_addr.ip_addr, &remote_addr.port);
-
-    local_addr.ip_addr.family = IPADDR_UNSPEC;
-    local_addr.sock_fd = sock_fd;
-
-    for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
-#ifdef IP_PKTINFO
-      if (cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_PKTINFO) {
-        struct in_pktinfo ipi;
-
-        memcpy(&ipi, CMSG_DATA(cmsg), sizeof(ipi));
-        local_addr.ip_addr.addr.in4 = ntohl(ipi.ipi_spec_dst.s_addr);
-        local_addr.ip_addr.family = IPADDR_INET4;
-      }
-#endif
-
-#if defined(IPV6_PKTINFO) && defined(HAVE_IN6_PKTINFO)
-      if (cmsg->cmsg_level == IPPROTO_IPV6 && cmsg->cmsg_type == IPV6_PKTINFO) {
-        struct in6_pktinfo ipi;
-
-        memcpy(&ipi, CMSG_DATA(cmsg), sizeof(ipi));
-        memcpy(&local_addr.ip_addr.addr.in6, &ipi.ipi6_addr.s6_addr,
-            sizeof (local_addr.ip_addr.addr.in6));
-        local_addr.ip_addr.family = IPADDR_INET6;
-      }
-#endif
-
-#ifdef SO_TIMESTAMP
-      if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SO_TIMESTAMP) {
-        struct timeval tv;
-
-        memcpy(&tv, CMSG_DATA(cmsg), sizeof(tv));
-        LCL_CookTime(&tv, &now, &now_err);
-      }
-#endif
-    }
-
-    DEBUG_LOG(LOGF_NtpIO, "Received %d bytes from %s:%d to %s fd %d",
-              status, UTI_IPToString(&remote_addr.ip_addr), remote_addr.port,
-              UTI_IPToString(&local_addr.ip_addr), local_addr.sock_fd);
-
-    if (status >= NTP_NORMAL_PACKET_LENGTH) {
-
-      NSR_ProcessReceive((NTP_Packet *) &message.ntp_pkt, &now, now_err,
-                         &remote_addr, &local_addr, status);
-
-    } else {
-
-      /* Just ignore the packet if it's not of a recognized length */
-
-    }
-  }
+  return server_sock_fd4 != INVALID_SOCK_FD || server_sock_fd6 != INVALID_SOCK_FD;
 }
 
 /* ================================================== */
-/* Send a packet to remote address from local address */
 
-static int
-send_packet(void *packet, int packetlen, NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr)
+int
+NIO_IsServerConnectable(NTP_Remote_Address *remote_addr)
 {
-  union sockaddr_in46 remote;
-  struct msghdr msg;
-  struct iovec iov;
-  char cmsgbuf[256];
-  int cmsglen;
-  socklen_t addrlen = 0;
+  int sock_fd;
 
-  assert(initialised);
-
-  if (local_addr->sock_fd == INVALID_SOCK_FD) {
-    DEBUG_LOG(LOGF_NtpIO, "No socket to send to %s:%d",
-              UTI_IPToString(&remote_addr->ip_addr), remote_addr->port);
+  sock_fd = open_separate_client_socket(remote_addr);
+  if (sock_fd == INVALID_SOCK_FD)
     return 0;
-  }
 
-  /* Don't set address with connected socket */
-  if (local_addr->sock_fd == server_sock_fd4 ||
-#ifdef FEAT_IPV6
-      local_addr->sock_fd == server_sock_fd6 ||
-#endif
-      !separate_client_sockets) {
-    addrlen = UTI_IPAndPortToSockaddr(&remote_addr->ip_addr, remote_addr->port,
-                                      &remote.u);
-    if (!addrlen)
-      return 0;
-  }
-
-  if (addrlen) {
-    msg.msg_name = &remote.u;
-    msg.msg_namelen = addrlen;
-  } else {
-    msg.msg_name = NULL;
-    msg.msg_namelen = 0;
-  }
-
-  iov.iov_base = packet;
-  iov.iov_len = packetlen;
-  msg.msg_iov = &iov;
-  msg.msg_iovlen = 1;
-  msg.msg_control = cmsgbuf;
-  msg.msg_controllen = sizeof(cmsgbuf);
-  msg.msg_flags = 0;
-  cmsglen = 0;
-
-#ifdef IP_PKTINFO
-  if (local_addr->ip_addr.family == IPADDR_INET4) {
-    struct cmsghdr *cmsg;
-    struct in_pktinfo *ipi;
-
-    cmsg = CMSG_FIRSTHDR(&msg);
-    memset(cmsg, 0, CMSG_SPACE(sizeof(struct in_pktinfo)));
-    cmsglen += CMSG_SPACE(sizeof(struct in_pktinfo));
-
-    cmsg->cmsg_level = IPPROTO_IP;
-    cmsg->cmsg_type = IP_PKTINFO;
-    cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
-
-    ipi = (struct in_pktinfo *) CMSG_DATA(cmsg);
-    ipi->ipi_spec_dst.s_addr = htonl(local_addr->ip_addr.addr.in4);
-  }
-#endif
-
-#if defined(IPV6_PKTINFO) && defined(HAVE_IN6_PKTINFO)
-  if (local_addr->ip_addr.family == IPADDR_INET6) {
-    struct cmsghdr *cmsg;
-    struct in6_pktinfo *ipi;
-
-    cmsg = CMSG_FIRSTHDR(&msg);
-    memset(cmsg, 0, CMSG_SPACE(sizeof(struct in6_pktinfo)));
-    cmsglen += CMSG_SPACE(sizeof(struct in6_pktinfo));
-
-    cmsg->cmsg_level = IPPROTO_IPV6;
-    cmsg->cmsg_type = IPV6_PKTINFO;
-    cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
-
-    ipi = (struct in6_pktinfo *) CMSG_DATA(cmsg);
-    memcpy(&ipi->ipi6_addr.s6_addr, &local_addr->ip_addr.addr.in6,
-        sizeof(ipi->ipi6_addr.s6_addr));
-  }
-#endif
-
-  msg.msg_controllen = cmsglen;
-  /* This is apparently required on some systems */
-  if (!cmsglen)
-    msg.msg_control = NULL;
-
-  if (sendmsg(local_addr->sock_fd, &msg, 0) < 0) {
-    DEBUG_LOG(LOGF_NtpIO, "Could not send to %s:%d from %s fd %d : %s",
-        UTI_IPToString(&remote_addr->ip_addr), remote_addr->port,
-        UTI_IPToString(&local_addr->ip_addr), local_addr->sock_fd,
-        strerror(errno));
-    return 0;
-  }
-
-  DEBUG_LOG(LOGF_NtpIO, "Sent %d bytes to %s:%d from %s fd %d", packetlen,
-      UTI_IPToString(&remote_addr->ip_addr), remote_addr->port,
-      UTI_IPToString(&local_addr->ip_addr), local_addr->sock_fd);
+  close_socket(sock_fd);
 
   return 1;
 }
 
 /* ================================================== */
-/* Send a packet to a given address */
+
+static void
+process_message(SCK_Message *message, int sock_fd, int event)
+{
+  NTP_Local_Address local_addr;
+  NTP_Local_Timestamp local_ts;
+  struct timespec sched_ts;
+
+  SCH_GetLastEventTime(&local_ts.ts, &local_ts.err, NULL);
+  local_ts.source = NTP_TS_DAEMON;
+  sched_ts = local_ts.ts;
+
+  if (message->addr_type != SCK_ADDR_IP) {
+    DEBUG_LOG("Unexpected address type");
+    return;
+  }
+
+  local_addr.ip_addr = message->local_addr.ip;
+  local_addr.if_index = message->if_index;;
+  local_addr.sock_fd = sock_fd;
+
+#ifdef HAVE_LINUX_TIMESTAMPING
+  if (NIO_Linux_ProcessMessage(message, &local_addr, &local_ts, event))
+    return;
+#else
+  if (!UTI_IsZeroTimespec(&message->timestamp.kernel)) {
+    LCL_CookTime(&message->timestamp.kernel, &local_ts.ts, &local_ts.err);
+    local_ts.source = NTP_TS_KERNEL;
+  }
+#endif
+
+  if (local_ts.source != NTP_TS_DAEMON)
+    DEBUG_LOG("Updated RX timestamp delay=%.9f tss=%u",
+              UTI_DiffTimespecsToDouble(&sched_ts, &local_ts.ts), local_ts.source);
+
+  /* Just ignore the packet if it's not of a recognized length */
+  if (message->length < NTP_HEADER_LENGTH || message->length > sizeof (NTP_Packet)) {
+    DEBUG_LOG("Unexpected length");
+    return;
+  }
+
+  NSR_ProcessRx(&message->remote_addr.ip, &local_addr, &local_ts, message->data, message->length);
+}
+
+/* ================================================== */
+
+static void
+read_from_socket(int sock_fd, int event, void *anything)
+{
+  SCK_Message *messages;
+  int i, received, flags = 0;
+
+#ifdef HAVE_LINUX_TIMESTAMPING
+  if (NIO_Linux_ProcessEvent(sock_fd, event))
+    return;
+#endif
+
+  if (event == SCH_FILE_EXCEPTION) {
+#ifdef HAVE_LINUX_TIMESTAMPING
+    flags |= SCK_FLAG_MSG_ERRQUEUE;
+#else
+    assert(0);
+#endif
+  }
+
+  messages = SCK_ReceiveMessages(sock_fd, flags, &received);
+  if (!messages)
+    return;
+
+  for (i = 0; i < received; i++)
+    process_message(&messages[i], sock_fd, event);
+}
+
+/* ================================================== */
+/* Send a packet to remote address from local address */
 
 int
-NIO_SendPacket(NTP_Packet *packet, NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr, int length)
+NIO_SendPacket(NTP_Packet *packet, NTP_Remote_Address *remote_addr,
+               NTP_Local_Address *local_addr, int length, int process_tx)
 {
-  return send_packet((void *) packet, length, remote_addr, local_addr);
+  SCK_Message message;
+
+  assert(initialised);
+
+  if (local_addr->sock_fd == INVALID_SOCK_FD) {
+    DEBUG_LOG("No socket to send to %s", UTI_IPSockAddrToString(remote_addr));
+    return 0;
+  }
+
+  SCK_InitMessage(&message, SCK_ADDR_IP);
+
+  message.data = packet;
+  message.length = length;
+
+  /* Specify remote address if the socket is not connected */
+  if (NIO_IsServerSocket(local_addr->sock_fd) || !separate_client_sockets) {
+    message.remote_addr.ip.ip_addr = remote_addr->ip_addr;
+    message.remote_addr.ip.port = remote_addr->port;
+  }
+
+  message.if_index = local_addr->if_index;
+  message.local_addr.ip = local_addr->ip_addr;
+
+#if !defined(HAVE_IN_PKTINFO) && defined(IP_SENDSRCADDR)
+  /* On FreeBSD a local IPv4 address cannot be specified on bound socket */
+  if (message.local_addr.ip.family == IPADDR_INET4 &&
+      (local_addr->sock_fd != server_sock_fd4 || bound_server_sock_fd4))
+    message.local_addr.ip.family = IPADDR_UNSPEC;
+#endif
+
+#ifdef HAVE_LINUX_TIMESTAMPING
+  if (process_tx)
+    NIO_Linux_RequestTxTimestamp(&message, local_addr->sock_fd);
+#endif
+
+  if (!SCK_SendMessage(local_addr->sock_fd, &message, 0))
+    return 0;
+
+  return 1;
 }

ntp_io.h

@@ -53,7 +53,14 @@ extern void NIO_CloseServerSocket(int sock_fd);
 /* Function to check if socket is a server socket */
 extern int NIO_IsServerSocket(int sock_fd);
 
+/* Function to check if a server socket is currently open */
+extern int NIO_IsServerSocketOpen(void);
+
+/* Function to check if client packets can be sent to a server */
+extern int NIO_IsServerConnectable(NTP_Remote_Address *remote_addr);
+
 /* Function to transmit a packet */
-extern int NIO_SendPacket(NTP_Packet *packet, NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr, int length);
+extern int NIO_SendPacket(NTP_Packet *packet, NTP_Remote_Address *remote_addr,
+                          NTP_Local_Address *local_addr, int length, int process_tx);
 
 #endif /* GOT_NTP_IO_H */

ntp_io_linux.c

@@ -0,0 +1,813 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2016-2019
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Functions for NTP I/O specific to Linux
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include <ifaddrs.h>
+#include <linux/ethtool.h>
+#include <linux/net_tstamp.h>
+#include <linux/sockios.h>
+#include <net/if.h>
+
+#include "array.h"
+#include "conf.h"
+#include "hwclock.h"
+#include "local.h"
+#include "logging.h"
+#include "ntp_core.h"
+#include "ntp_io.h"
+#include "ntp_io_linux.h"
+#include "ntp_sources.h"
+#include "sched.h"
+#include "socket.h"
+#include "sys_linux.h"
+#include "util.h"
+
+struct Interface {
+  char name[IF_NAMESIZE];
+  int if_index;
+  int phc_fd;
+  int phc_mode;
+  int phc_nocrossts;
+  /* Link speed in mbit/s */
+  int link_speed;
+  /* Start of UDP data at layer 2 for IPv4 and IPv6 */
+  int l2_udp4_ntp_start;
+  int l2_udp6_ntp_start;
+  /* Precision of PHC readings */
+  double precision;
+  /* Compensation of errors in TX and RX timestamping */
+  double tx_comp;
+  double rx_comp;
+  HCL_Instance clock;
+};
+
+/* Number of PHC readings per HW clock sample */
+#define PHC_READINGS 10
+
+/* Minimum interval between PHC readings */
+#define MIN_PHC_POLL -6
+
+/* Maximum acceptable offset between HW and daemon/kernel timestamp */
+#define MAX_TS_DELAY 1.0
+
+/* Array of Interfaces */
+static ARR_Instance interfaces;
+
+/* RX/TX and TX-specific timestamping socket options */
+static int ts_flags;
+static int ts_tx_flags;
+
+/* Flag indicating the socket options can't be changed in control messages */
+static int permanent_ts_options;
+
+/* When sending client requests to a close and fast server, it is possible that
+   a response will be received before the HW transmit timestamp of the request
+   itself.  To avoid processing of the response without the HW timestamp, we
+   monitor events returned by select() and suspend reading of packets from the
+   receive queue for up to 200 microseconds.  As the requests are normally
+   separated by at least 200 milliseconds, it is sufficient to monitor and
+   suspend one socket at a time. */
+static int monitored_socket;
+static int suspended_socket;
+static SCH_TimeoutID resume_timeout_id;
+
+#define RESUME_TIMEOUT 200.0e-6
+
+/* Unbound socket keeping the kernel RX timestamping permanently enabled
+   in order to avoid a race condition between receiving a server response
+   and the kernel actually starting to timestamp received packets after
+   enabling the timestamping and sending a request */
+static int dummy_rxts_socket;
+
+#define INVALID_SOCK_FD -3
+
+/* ================================================== */
+
+static int
+add_interface(CNF_HwTsInterface *conf_iface)
+{
+  struct ethtool_ts_info ts_info;
+  struct hwtstamp_config ts_config;
+  struct ifreq req;
+  int sock_fd, if_index, phc_fd, req_hwts_flags, rx_filter;
+  unsigned int i;
+  struct Interface *iface;
+
+  /* Check if the interface was not already added */
+  for (i = 0; i < ARR_GetSize(interfaces); i++) {
+    if (!strcmp(conf_iface->name, ((struct Interface *)ARR_GetElement(interfaces, i))->name))
+      return 1;
+  }
+
+  sock_fd = SCK_OpenUdpSocket(NULL, NULL, 0);
+  if (sock_fd < 0)
+    return 0;
+
+  memset(&req, 0, sizeof (req));
+  memset(&ts_info, 0, sizeof (ts_info));
+
+  if (snprintf(req.ifr_name, sizeof (req.ifr_name), "%s", conf_iface->name) >=
+      sizeof (req.ifr_name)) {
+    SCK_CloseSocket(sock_fd);
+    return 0;
+  }
+
+  if (ioctl(sock_fd, SIOCGIFINDEX, &req)) {
+    DEBUG_LOG("ioctl(%s) failed : %s", "SIOCGIFINDEX", strerror(errno));
+    SCK_CloseSocket(sock_fd);
+    return 0;
+  }
+
+  if_index = req.ifr_ifindex;
+
+  ts_info.cmd = ETHTOOL_GET_TS_INFO;
+  req.ifr_data = (char *)&ts_info;
+
+  if (ioctl(sock_fd, SIOCETHTOOL, &req)) {
+    DEBUG_LOG("ioctl(%s) failed : %s", "SIOCETHTOOL", strerror(errno));
+    SCK_CloseSocket(sock_fd);
+    return 0;
+  }
+
+  req_hwts_flags = SOF_TIMESTAMPING_RX_HARDWARE | SOF_TIMESTAMPING_TX_HARDWARE |
+                   SOF_TIMESTAMPING_RAW_HARDWARE;
+  if ((ts_info.so_timestamping & req_hwts_flags) != req_hwts_flags) {
+    DEBUG_LOG("HW timestamping not supported on %s", req.ifr_name);
+    SCK_CloseSocket(sock_fd);
+    return 0;
+  }
+
+  if (ts_info.phc_index < 0) {
+    DEBUG_LOG("PHC missing on %s", req.ifr_name);
+    SCK_CloseSocket(sock_fd);
+    return 0;
+  }
+
+  switch (conf_iface->rxfilter) {
+    case CNF_HWTS_RXFILTER_ANY:
+#ifdef HAVE_LINUX_TIMESTAMPING_RXFILTER_NTP
+      if (ts_info.rx_filters & (1 << HWTSTAMP_FILTER_NTP_ALL))
+        rx_filter = HWTSTAMP_FILTER_NTP_ALL;
+      else
+#endif
+      if (ts_info.rx_filters & (1 << HWTSTAMP_FILTER_ALL))
+        rx_filter = HWTSTAMP_FILTER_ALL;
+      else
+        rx_filter = HWTSTAMP_FILTER_NONE;
+      break;
+    case CNF_HWTS_RXFILTER_NONE:
+      rx_filter = HWTSTAMP_FILTER_NONE;
+      break;
+#ifdef HAVE_LINUX_TIMESTAMPING_RXFILTER_NTP
+    case CNF_HWTS_RXFILTER_NTP:
+      rx_filter = HWTSTAMP_FILTER_NTP_ALL;
+      break;
+#endif
+    default:
+      rx_filter = HWTSTAMP_FILTER_ALL;
+      break;
+  }
+
+  ts_config.flags = 0;
+  ts_config.tx_type = HWTSTAMP_TX_ON;
+  ts_config.rx_filter = rx_filter;
+  req.ifr_data = (char *)&ts_config;
+
+  if (ioctl(sock_fd, SIOCSHWTSTAMP, &req)) {
+    DEBUG_LOG("ioctl(%s) failed : %s", "SIOCSHWTSTAMP", strerror(errno));
+
+    /* Check the current timestamping configuration in case this interface
+       allows only reading of the configuration and it was already configured
+       as requested */
+    req.ifr_data = (char *)&ts_config;
+#ifdef SIOCGHWTSTAMP
+    if (ioctl(sock_fd, SIOCGHWTSTAMP, &req) ||
+        ts_config.tx_type != HWTSTAMP_TX_ON || ts_config.rx_filter != rx_filter)
+#endif
+    {
+      SCK_CloseSocket(sock_fd);
+      return 0;
+    }
+  }
+
+  SCK_CloseSocket(sock_fd);
+
+  phc_fd = SYS_Linux_OpenPHC(NULL, ts_info.phc_index);
+  if (phc_fd < 0)
+    return 0;
+
+  iface = ARR_GetNewElement(interfaces);
+
+  snprintf(iface->name, sizeof (iface->name), "%s", conf_iface->name);
+  iface->if_index = if_index;
+  iface->phc_fd = phc_fd;
+  iface->phc_mode = 0;
+  iface->phc_nocrossts = conf_iface->nocrossts;
+
+  /* Start with 1 gbit and no VLANs or IPv4/IPv6 options */
+  iface->link_speed = 1000;
+  iface->l2_udp4_ntp_start = 42;
+  iface->l2_udp6_ntp_start = 62;
+
+  iface->precision = conf_iface->precision;
+  iface->tx_comp = conf_iface->tx_comp;
+  iface->rx_comp = conf_iface->rx_comp;
+
+  iface->clock = HCL_CreateInstance(conf_iface->min_samples, conf_iface->max_samples,
+                                    UTI_Log2ToDouble(MAX(conf_iface->minpoll, MIN_PHC_POLL)));
+
+  LOG(LOGS_INFO, "Enabled HW timestamping %son %s",
+      ts_config.rx_filter == HWTSTAMP_FILTER_NONE ? "(TX only) " : "", iface->name);
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+add_all_interfaces(CNF_HwTsInterface *conf_iface_all)
+{
+  CNF_HwTsInterface conf_iface;
+  struct ifaddrs *ifaddr, *ifa;
+  int r;
+
+  conf_iface = *conf_iface_all;
+
+  if (getifaddrs(&ifaddr)) {
+    DEBUG_LOG("getifaddrs() failed : %s", strerror(errno));
+    return 0;
+  }
+
+  for (r = 0, ifa = ifaddr; ifa; ifa = ifa->ifa_next) {
+    conf_iface.name = ifa->ifa_name;
+    if (add_interface(&conf_iface))
+      r = 1;
+  }
+  
+  freeifaddrs(ifaddr);
+
+  /* Return success if at least one interface was added */
+  return r;
+}
+
+/* ================================================== */
+
+static void
+update_interface_speed(struct Interface *iface)
+{
+  struct ethtool_cmd cmd;
+  struct ifreq req;
+  int sock_fd, link_speed;
+
+  sock_fd = SCK_OpenUdpSocket(NULL, NULL, 0);
+  if (sock_fd < 0)
+    return;
+
+  memset(&req, 0, sizeof (req));
+  memset(&cmd, 0, sizeof (cmd));
+
+  snprintf(req.ifr_name, sizeof (req.ifr_name), "%s", iface->name);
+  cmd.cmd = ETHTOOL_GSET;
+  req.ifr_data = (char *)&cmd;
+
+  if (ioctl(sock_fd, SIOCETHTOOL, &req)) {
+    DEBUG_LOG("ioctl(%s) failed : %s", "SIOCETHTOOL", strerror(errno));
+    SCK_CloseSocket(sock_fd);
+    return;
+  }
+
+  SCK_CloseSocket(sock_fd);
+
+  link_speed = ethtool_cmd_speed(&cmd);
+
+  if (iface->link_speed != link_speed) {
+    iface->link_speed = link_speed;
+    DEBUG_LOG("Updated speed of %s to %d Mb/s", iface->name, link_speed);
+  }
+}
+
+/* ================================================== */
+
+#if defined(HAVE_LINUX_TIMESTAMPING_OPT_PKTINFO) || defined(HAVE_LINUX_TIMESTAMPING_OPT_TX_SWHW)
+static int
+check_timestamping_option(int option)
+{
+  int sock_fd;
+
+  sock_fd = SCK_OpenUdpSocket(NULL, NULL, 0);
+  if (sock_fd < 0)
+    return 0;
+
+  if (!SCK_SetIntOption(sock_fd, SOL_SOCKET, SO_TIMESTAMPING, option)) {
+    SCK_CloseSocket(sock_fd);
+    return 0;
+  }
+
+  SCK_CloseSocket(sock_fd);
+  return 1;
+}
+#endif
+
+/* ================================================== */
+
+static int
+open_dummy_socket(void)
+{
+  int sock_fd, events = 0;
+
+  sock_fd = SCK_OpenUdpSocket(NULL, NULL, 0);
+  if (sock_fd < 0)
+    return INVALID_SOCK_FD;
+
+  if (!NIO_Linux_SetTimestampSocketOptions(sock_fd, 1, &events)) {
+    SCK_CloseSocket(sock_fd);
+    return INVALID_SOCK_FD;
+  }
+
+  return sock_fd;
+}
+
+/* ================================================== */
+
+void
+NIO_Linux_Initialise(void)
+{
+  CNF_HwTsInterface *conf_iface;
+  unsigned int i;
+  int hwts;
+
+  interfaces = ARR_CreateInstance(sizeof (struct Interface));
+
+  /* Enable HW timestamping on specified interfaces.  If "*" was specified, try
+     all interfaces.  If no interface was specified, enable SW timestamping. */
+
+  for (i = hwts = 0; CNF_GetHwTsInterface(i, &conf_iface); i++) {
+    if (!strcmp("*", conf_iface->name))
+      continue;
+    if (!add_interface(conf_iface))
+      LOG_FATAL("Could not enable HW timestamping on %s", conf_iface->name);
+    hwts = 1;
+  }
+
+  for (i = 0; CNF_GetHwTsInterface(i, &conf_iface); i++) {
+    if (strcmp("*", conf_iface->name))
+      continue;
+    if (add_all_interfaces(conf_iface))
+      hwts = 1;
+    break;
+  }
+
+  ts_flags = SOF_TIMESTAMPING_SOFTWARE | SOF_TIMESTAMPING_RX_SOFTWARE;
+  ts_tx_flags = SOF_TIMESTAMPING_TX_SOFTWARE;
+
+  if (hwts) {
+    ts_flags |= SOF_TIMESTAMPING_RAW_HARDWARE | SOF_TIMESTAMPING_RX_HARDWARE;
+    ts_tx_flags |= SOF_TIMESTAMPING_TX_HARDWARE;
+#ifdef HAVE_LINUX_TIMESTAMPING_OPT_PKTINFO
+    if (check_timestamping_option(SOF_TIMESTAMPING_OPT_PKTINFO))
+      ts_flags |= SOF_TIMESTAMPING_OPT_PKTINFO;
+#endif
+#ifdef HAVE_LINUX_TIMESTAMPING_OPT_TX_SWHW
+    if (check_timestamping_option(SOF_TIMESTAMPING_OPT_TX_SWHW))
+      ts_flags |= SOF_TIMESTAMPING_OPT_TX_SWHW;
+#endif
+  }
+
+  /* Enable IP_PKTINFO in messages looped back to the error queue */
+  ts_flags |= SOF_TIMESTAMPING_OPT_CMSG;
+
+  /* Kernels before 4.7 ignore timestamping flags set in control messages */
+  permanent_ts_options = !SYS_Linux_CheckKernelVersion(4, 7);
+
+  monitored_socket = INVALID_SOCK_FD;
+  suspended_socket = INVALID_SOCK_FD;
+  dummy_rxts_socket = INVALID_SOCK_FD;
+}
+
+/* ================================================== */
+
+void
+NIO_Linux_Finalise(void)
+{
+  struct Interface *iface;
+  unsigned int i;
+
+  if (dummy_rxts_socket != INVALID_SOCK_FD)
+    SCK_CloseSocket(dummy_rxts_socket);
+
+  for (i = 0; i < ARR_GetSize(interfaces); i++) {
+    iface = ARR_GetElement(interfaces, i);
+    HCL_DestroyInstance(iface->clock);
+    close(iface->phc_fd);
+  }
+
+  ARR_DestroyInstance(interfaces);
+}
+
+/* ================================================== */
+
+int
+NIO_Linux_SetTimestampSocketOptions(int sock_fd, int client_only, int *events)
+{
+  int val, flags;
+
+  if (!ts_flags)
+    return 0;
+
+  /* Enable SCM_TIMESTAMPING control messages and the socket's error queue in
+     order to receive our transmitted packets with more accurate timestamps */
+
+  val = 1;
+  flags = ts_flags;
+
+  if (client_only || permanent_ts_options)
+    flags |= ts_tx_flags;
+
+  if (!SCK_SetIntOption(sock_fd, SOL_SOCKET, SO_SELECT_ERR_QUEUE, val)) {
+    ts_flags = 0;
+    return 0;
+  }
+
+  if (!SCK_SetIntOption(sock_fd, SOL_SOCKET, SO_TIMESTAMPING, flags)) {
+    ts_flags = 0;
+    return 0;
+  }
+
+  *events |= SCH_FILE_EXCEPTION;
+  return 1;
+}
+
+/* ================================================== */
+
+static void
+resume_socket(int sock_fd)
+{
+  if (monitored_socket == sock_fd)
+    monitored_socket = INVALID_SOCK_FD;
+
+  if (sock_fd == INVALID_SOCK_FD || sock_fd != suspended_socket)
+    return;
+
+  suspended_socket = INVALID_SOCK_FD;
+
+  SCH_SetFileHandlerEvent(sock_fd, SCH_FILE_INPUT, 1);
+
+  DEBUG_LOG("Resumed RX processing %s timeout fd=%d",
+            resume_timeout_id ? "before" : "on", sock_fd);
+
+  if (resume_timeout_id) {
+    SCH_RemoveTimeout(resume_timeout_id);
+    resume_timeout_id = 0;
+  }
+}
+
+/* ================================================== */
+
+static void
+resume_timeout(void *arg)
+{
+  resume_timeout_id = 0;
+  resume_socket(suspended_socket);
+}
+
+/* ================================================== */
+
+static void
+suspend_socket(int sock_fd)
+{
+  resume_socket(suspended_socket);
+
+  suspended_socket = sock_fd;
+
+  SCH_SetFileHandlerEvent(suspended_socket, SCH_FILE_INPUT, 0);
+  resume_timeout_id = SCH_AddTimeoutByDelay(RESUME_TIMEOUT, resume_timeout, NULL);
+
+  DEBUG_LOG("Suspended RX processing fd=%d", sock_fd);
+}
+
+/* ================================================== */
+
+int
+NIO_Linux_ProcessEvent(int sock_fd, int event)
+{
+  if (sock_fd != monitored_socket)
+    return 0;
+
+  if (event == SCH_FILE_INPUT) {
+    suspend_socket(monitored_socket);
+    monitored_socket = INVALID_SOCK_FD;
+
+    /* Don't process the message yet */
+    return 1;
+  }
+
+  return 0;
+}
+
+/* ================================================== */
+
+static struct Interface *
+get_interface(int if_index)
+{
+  struct Interface *iface;
+  unsigned int i;
+
+  for (i = 0; i < ARR_GetSize(interfaces); i++) {
+    iface = ARR_GetElement(interfaces, i);
+    if (iface->if_index != if_index)
+      continue;
+
+    return iface;
+  }
+
+  return NULL;
+}
+
+/* ================================================== */
+
+static void
+process_hw_timestamp(struct Interface *iface, struct timespec *hw_ts,
+                     NTP_Local_Timestamp *local_ts, int rx_ntp_length, int family,
+                     int l2_length)
+{
+  struct timespec sample_phc_ts, sample_sys_ts, sample_local_ts, ts;
+  double rx_correction, ts_delay, phc_err, local_err;
+
+  if (HCL_NeedsNewSample(iface->clock, &local_ts->ts)) {
+    if (!SYS_Linux_GetPHCSample(iface->phc_fd, iface->phc_nocrossts, iface->precision,
+                                &iface->phc_mode, &sample_phc_ts, &sample_sys_ts,
+                                &phc_err))
+      return;
+
+    LCL_CookTime(&sample_sys_ts, &sample_local_ts, &local_err);
+    HCL_AccumulateSample(iface->clock, &sample_phc_ts, &sample_local_ts,
+                         phc_err + local_err);
+
+    update_interface_speed(iface);
+  }
+
+  /* We need to transpose RX timestamps as hardware timestamps are normally
+     preamble timestamps and RX timestamps in NTP are supposed to be trailer
+     timestamps.  If we don't know the length of the packet at layer 2, we
+     make an assumption that UDP data start at the same position as in the
+     last transmitted packet which had a HW TX timestamp. */
+  if (rx_ntp_length && iface->link_speed) {
+    if (!l2_length)
+      l2_length = (family == IPADDR_INET4 ? iface->l2_udp4_ntp_start :
+                   iface->l2_udp6_ntp_start) + rx_ntp_length;
+
+    /* Include the frame check sequence (FCS) */
+    l2_length += 4;
+
+    rx_correction = l2_length / (1.0e6 / 8 * iface->link_speed);
+
+    UTI_AddDoubleToTimespec(hw_ts, rx_correction, hw_ts);
+  }
+
+  if (!HCL_CookTime(iface->clock, hw_ts, &ts, &local_err))
+    return;
+
+  if (!rx_ntp_length && iface->tx_comp)
+    UTI_AddDoubleToTimespec(&ts, iface->tx_comp, &ts);
+  else if (rx_ntp_length && iface->rx_comp)
+    UTI_AddDoubleToTimespec(&ts, -iface->rx_comp, &ts);
+
+  ts_delay = UTI_DiffTimespecsToDouble(&local_ts->ts, &ts);
+
+  if (fabs(ts_delay) > MAX_TS_DELAY) {
+    DEBUG_LOG("Unacceptable timestamp delay %.9f", ts_delay);
+    return;
+  }
+
+  local_ts->ts = ts;
+  local_ts->err = local_err;
+  local_ts->source = NTP_TS_HARDWARE;
+}
+
+/* ================================================== */
+/* Extract UDP data from a layer 2 message.  Supported is Ethernet
+   with optional VLAN tags. */
+
+static int
+extract_udp_data(unsigned char *msg, NTP_Remote_Address *remote_addr, int len)
+{
+  unsigned char *msg_start = msg;
+
+  remote_addr->ip_addr.family = IPADDR_UNSPEC;
+  remote_addr->port = 0;
+
+  /* Skip MACs */
+  if (len < 12)
+    return 0;
+  len -= 12, msg += 12;
+
+  /* Skip VLAN tag(s) if present */
+  while (len >= 4 && msg[0] == 0x81 && msg[1] == 0x00)
+    len -= 4, msg += 4;
+
+  /* Skip IPv4 or IPv6 ethertype */
+  if (len < 2 || !((msg[0] == 0x08 && msg[1] == 0x00) ||
+                   (msg[0] == 0x86 && msg[1] == 0xdd)))
+    return 0;
+  len -= 2, msg += 2;
+
+  /* Parse destination address and port from IPv4/IPv6 and UDP headers */
+  if (len >= 20 && msg[0] >> 4 == 4) {
+    int ihl = (msg[0] & 0xf) * 4;
+    uint32_t addr;
+
+    if (len < ihl + 8 || msg[9] != 17)
+      return 0;
+
+    memcpy(&addr, msg + 16, sizeof (addr));
+    remote_addr->ip_addr.addr.in4 = ntohl(addr);
+    remote_addr->port = ntohs(*(uint16_t *)(msg + ihl + 2));
+    remote_addr->ip_addr.family = IPADDR_INET4;
+    len -= ihl + 8, msg += ihl + 8;
+#ifdef FEAT_IPV6
+  } else if (len >= 48 && msg[0] >> 4 == 6) {
+    int eh_len, next_header = msg[6];
+
+    memcpy(&remote_addr->ip_addr.addr.in6, msg + 24, sizeof (remote_addr->ip_addr.addr.in6));
+    len -= 40, msg += 40;
+
+    /* Skip IPv6 extension headers if present */
+    while (next_header != 17) {
+      switch (next_header) {
+        case 44:  /* Fragment Header */
+          /* Process only the first fragment */
+          if (ntohs(*(uint16_t *)(msg + 2)) >> 3 != 0)
+            return 0;
+          eh_len = 8;
+          break;
+        case 0:   /* Hop-by-Hop Options */
+        case 43:  /* Routing Header */
+        case 60:  /* Destination Options */
+        case 135: /* Mobility Header */
+          eh_len = 8 * (msg[1] + 1);
+          break;
+        case 51:  /* Authentication Header */
+          eh_len = 4 * (msg[1] + 2);
+          break;
+        default:
+          return 0;
+      }
+
+      if (eh_len < 8 || len < eh_len + 8)
+        return 0;
+
+      next_header = msg[0];
+      len -= eh_len, msg += eh_len;
+    }
+
+    remote_addr->port = ntohs(*(uint16_t *)(msg + 2));
+    remote_addr->ip_addr.family = IPADDR_INET6;
+    len -= 8, msg += 8;
+#endif
+  } else {
+    return 0;
+  }
+
+  /* Move the message to fix alignment of its fields */
+  if (len > 0)
+    memmove(msg_start, msg, len);
+
+  return len;
+}
+
+/* ================================================== */
+
+int
+NIO_Linux_ProcessMessage(SCK_Message *message, NTP_Local_Address *local_addr,
+                         NTP_Local_Timestamp *local_ts, int event)
+{
+  struct Interface *iface;
+  int is_tx, ts_if_index, l2_length;
+
+  is_tx = event == SCH_FILE_EXCEPTION;
+  iface = NULL;
+
+  ts_if_index = message->timestamp.if_index;
+  if (ts_if_index == INVALID_IF_INDEX)
+    ts_if_index = message->if_index;
+  l2_length = message->timestamp.l2_length;
+
+  if (!UTI_IsZeroTimespec(&message->timestamp.hw)) {
+    iface = get_interface(ts_if_index);
+    if (iface) {
+      process_hw_timestamp(iface, &message->timestamp.hw, local_ts, !is_tx ? message->length : 0,
+                           message->remote_addr.ip.ip_addr.family, l2_length);
+    } else {
+      DEBUG_LOG("HW clock not found for interface %d", ts_if_index);
+    }
+
+    /* If a HW transmit timestamp was received, resume processing
+       of non-error messages on this socket */
+    if (is_tx)
+      resume_socket(local_addr->sock_fd);
+  }
+
+  if (local_ts->source == NTP_TS_DAEMON && !UTI_IsZeroTimespec(&message->timestamp.kernel) &&
+      (!is_tx || UTI_IsZeroTimespec(&message->timestamp.hw))) {
+    LCL_CookTime(&message->timestamp.kernel, &local_ts->ts, &local_ts->err);
+    local_ts->source = NTP_TS_KERNEL;
+  }
+
+  /* If the kernel is slow with enabling RX timestamping, open a dummy
+     socket to keep the kernel RX timestamping permanently enabled */
+  if (!is_tx && local_ts->source == NTP_TS_DAEMON && ts_flags) {
+    DEBUG_LOG("Missing kernel RX timestamp");
+    if (dummy_rxts_socket == INVALID_SOCK_FD)
+      dummy_rxts_socket = open_dummy_socket();
+  }
+
+  /* Return the message if it's not received from the error queue */
+  if (!is_tx)
+    return 0;
+
+  /* The data from the error queue includes all layers up to UDP.  We have to
+     extract the UDP data and also the destination address with port as there
+     currently doesn't seem to be a better way to get them both. */
+  l2_length = message->length;
+  message->length = extract_udp_data(message->data, &message->remote_addr.ip, message->length);
+
+  DEBUG_LOG("Extracted message for %s fd=%d len=%u",
+            UTI_IPSockAddrToString(&message->remote_addr.ip),
+            local_addr->sock_fd, message->length);
+
+  /* Update assumed position of UDP data at layer 2 for next received packet */
+  if (iface && message->length) {
+    if (message->remote_addr.ip.ip_addr.family == IPADDR_INET4)
+      iface->l2_udp4_ntp_start = l2_length - message->length;
+    else if (message->remote_addr.ip.ip_addr.family == IPADDR_INET6)
+      iface->l2_udp6_ntp_start = l2_length - message->length;
+  }
+
+  /* Drop the message if it has no timestamp or its processing failed */
+  if (local_ts->source == NTP_TS_DAEMON) {
+    DEBUG_LOG("Missing TX timestamp");
+    return 1;
+  }
+
+  if (message->length < NTP_HEADER_LENGTH)
+    return 1;
+
+  NSR_ProcessTx(&message->remote_addr.ip, local_addr, local_ts, message->data, message->length);
+
+  return 1;
+}
+
+/* ================================================== */
+
+void
+NIO_Linux_RequestTxTimestamp(SCK_Message *message, int sock_fd)
+{
+  if (!ts_flags)
+    return;
+
+  /* If a HW transmit timestamp is requested on a client socket, monitor
+     events on the socket in order to avoid processing of a fast response
+     without the HW timestamp of the request */
+  if (ts_tx_flags & SOF_TIMESTAMPING_TX_HARDWARE && !NIO_IsServerSocket(sock_fd))
+    monitored_socket = sock_fd;
+
+  /* Check if TX timestamping is disabled on this socket */
+  if (permanent_ts_options || !NIO_IsServerSocket(sock_fd))
+    return;
+
+  message->timestamp.tx_flags = ts_tx_flags;
+}
+
+/* ================================================== */
+
+void
+NIO_Linux_NotifySocketClosing(int sock_fd)
+{
+  resume_socket(sock_fd);
+}

ntp_io_linux.h

@@ -0,0 +1,47 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2016
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  This is the header file for the Linux-specific NTP socket I/O bits.
+  */
+
+#ifndef GOT_NTP_IO_LINUX_H
+#define GOT_NTP_IO_LINUX_H
+
+#include "socket.h"
+
+extern void NIO_Linux_Initialise(void);
+
+extern void NIO_Linux_Finalise(void);
+
+extern int NIO_Linux_SetTimestampSocketOptions(int sock_fd, int client_only, int *events);
+
+extern int NIO_Linux_ProcessEvent(int sock_fd, int event);
+
+extern int NIO_Linux_ProcessMessage(SCK_Message *message, NTP_Local_Address *local_addr,
+                                    NTP_Local_Timestamp *local_ts, int event);
+
+extern void NIO_Linux_RequestTxTimestamp(SCK_Message *message, int sock_fd);
+
+extern void NIO_Linux_NotifySocketClosing(int sock_fd);
+
+#endif

ntp_signd.c

@@ -0,0 +1,361 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2016
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Support for MS-SNTP authentication in Samba (ntp_signd)
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "array.h"
+#include "conf.h"
+#include "logging.h"
+#include "ntp_io.h"
+#include "ntp_signd.h"
+#include "sched.h"
+#include "socket.h"
+#include "util.h"
+
+/* Declarations per samba/source4/librpc/idl/ntp_signd.idl */
+
+#define SIGND_VERSION 0
+
+typedef enum {
+  SIGN_TO_CLIENT = 0,
+  ASK_SERVER_TO_SIGN = 1,
+  CHECK_SERVER_SIGNATURE = 2,
+  SIGNING_SUCCESS = 3,
+  SIGNING_FAILURE = 4,
+} SigndOp;
+
+typedef struct {
+  uint32_t length;
+  uint32_t version;
+  uint32_t op;
+  uint16_t packet_id;
+  uint16_t _pad;
+  uint32_t key_id;
+  NTP_Packet packet_to_sign;
+} SigndRequest;
+
+typedef struct {
+  uint32_t length;
+  uint32_t version;
+  uint32_t op;
+  uint32_t packet_id;
+  NTP_Packet signed_packet;
+} SigndResponse;
+
+typedef struct {
+  NTP_Remote_Address remote_addr;
+  NTP_Local_Address local_addr;
+
+  int sent;
+  int received;
+  int request_length;
+  struct timespec request_ts;
+  SigndRequest request;
+  SigndResponse response;
+} SignInstance;
+
+/* As the communication with ntp_signd is asynchronous, incoming packets are
+   saved in a queue in order to avoid loss when they come in bursts */
+
+#define MAX_QUEUE_LENGTH 16U
+#define NEXT_QUEUE_INDEX(index) (((index) + 1) % MAX_QUEUE_LENGTH)
+#define IS_QUEUE_EMPTY() (queue_head == queue_tail)
+
+/* Fixed-size array of SignInstance */
+static ARR_Instance queue;
+static unsigned int queue_head;
+static unsigned int queue_tail;
+
+#define INVALID_SOCK_FD (-6)
+
+/* Unix domain socket connected to ntp_signd */
+static int sock_fd;
+
+#define MIN_AUTH_DELAY 1.0e-5
+#define MAX_AUTH_DELAY 1.0e-2
+
+/* Average time needed for signing one packet.  This is used to adjust the
+   transmit timestamp in NTP packets.  The timestamp won't be very accurate as
+   the delay is variable, but it should be good enough for MS-SNTP clients. */
+static double auth_delay;
+
+/* Flag indicating if the MS-SNTP authentication is enabled */
+static int enabled;
+
+/* ================================================== */
+
+static void read_write_socket(int sock_fd, int event, void *anything);
+
+/* ================================================== */
+
+static void
+close_socket(void)
+{
+  SCH_RemoveFileHandler(sock_fd);
+  SCK_CloseSocket(sock_fd);
+  sock_fd = INVALID_SOCK_FD;
+
+  /* Empty the queue */
+  queue_head = queue_tail = 0;
+}
+
+/* ================================================== */
+
+static int
+open_socket(void)
+{
+  char path[PATH_MAX];
+
+  if (sock_fd != INVALID_SOCK_FD)
+    return 1;
+
+  if (snprintf(path, sizeof (path), "%s/socket", CNF_GetNtpSigndSocket()) >= sizeof (path)) {
+    DEBUG_LOG("signd socket path too long");
+    return 0;
+  }
+
+  sock_fd = SCK_OpenUnixStreamSocket(path, NULL, 0);
+  if (sock_fd < 0) {
+    sock_fd = INVALID_SOCK_FD;
+    return 0;
+  }
+
+  SCH_AddFileHandler(sock_fd, SCH_FILE_INPUT, read_write_socket, NULL);
+
+  return 1;
+}
+
+/* ================================================== */
+
+static void
+process_response(SignInstance *inst)
+{
+  struct timespec ts;
+  double delay;
+
+  if (ntohs(inst->request.packet_id) != ntohl(inst->response.packet_id)) {
+    DEBUG_LOG("Invalid response ID");
+    return;
+  }
+
+  if (ntohl(inst->response.op) != SIGNING_SUCCESS) {
+    DEBUG_LOG("Signing failed");
+    return;
+  }
+
+  /* Check if the file descriptor is still valid */
+  if (!NIO_IsServerSocket(inst->local_addr.sock_fd)) {
+    DEBUG_LOG("Invalid NTP socket");
+    return;
+  }
+
+  SCH_GetLastEventTime(NULL, NULL, &ts);
+  delay = UTI_DiffTimespecsToDouble(&ts, &inst->request_ts);
+
+  DEBUG_LOG("Signing succeeded (delay %f)", delay);
+
+  /* Send the signed NTP packet */
+  NIO_SendPacket(&inst->response.signed_packet, &inst->remote_addr, &inst->local_addr,
+                 ntohl(inst->response.length) + sizeof (inst->response.length) -
+                 offsetof(SigndResponse, signed_packet), 0);
+
+  /* Update exponential moving average of the authentication delay */
+  delay = CLAMP(MIN_AUTH_DELAY, delay, MAX_AUTH_DELAY);
+  auth_delay += 0.1 * (delay - auth_delay);
+}
+
+/* ================================================== */
+
+static void
+read_write_socket(int sock_fd, int event, void *anything)
+{
+  SignInstance *inst;
+  uint32_t response_length;
+  int s;
+
+  inst = ARR_GetElement(queue, queue_head);
+
+  if (event == SCH_FILE_OUTPUT) {
+    assert(!IS_QUEUE_EMPTY());
+    assert(inst->sent < inst->request_length);
+
+    if (!inst->sent)
+      SCH_GetLastEventTime(NULL, NULL, &inst->request_ts);
+
+    s = SCK_Send(sock_fd, (char *)&inst->request + inst->sent,
+                 inst->request_length - inst->sent, 0);
+
+    if (s < 0) {
+      close_socket();
+      return;
+    }
+
+    inst->sent += s;
+
+    /* Try again later if the request is not complete yet */
+    if (inst->sent < inst->request_length)
+      return;
+
+    /* Disable output and wait for a response */
+    SCH_SetFileHandlerEvent(sock_fd, SCH_FILE_OUTPUT, 0);
+  }
+
+  if (event == SCH_FILE_INPUT) {
+    if (IS_QUEUE_EMPTY()) {
+        DEBUG_LOG("Unexpected signd response");
+        close_socket();
+        return;
+    }
+
+    assert(inst->received < sizeof (inst->response));
+    s = SCK_Receive(sock_fd, (char *)&inst->response + inst->received,
+                    sizeof (inst->response) - inst->received, 0);
+
+    if (s <= 0) {
+      close_socket();
+      return;
+    }
+
+    inst->received += s;
+
+    if (inst->received < sizeof (inst->response.length))
+      return;
+
+    response_length = ntohl(inst->response.length) + sizeof (inst->response.length);
+
+    if (response_length < offsetof(SigndResponse, signed_packet) ||
+        response_length > sizeof (SigndResponse)) {
+      DEBUG_LOG("Invalid response length");
+      close_socket();
+      return;
+    }
+
+    /* Wait for more data if not complete yet */
+    if (inst->received < response_length)
+      return;
+
+    process_response(inst);
+
+    /* Move the head and enable output for the next packet */
+    queue_head = NEXT_QUEUE_INDEX(queue_head);
+    if (!IS_QUEUE_EMPTY())
+      SCH_SetFileHandlerEvent(sock_fd, SCH_FILE_OUTPUT, 1);
+  }
+}
+
+/* ================================================== */
+
+void
+NSD_Initialise()
+{
+  sock_fd = INVALID_SOCK_FD;
+  auth_delay = MIN_AUTH_DELAY;
+  enabled = CNF_GetNtpSigndSocket() && CNF_GetNtpSigndSocket()[0];
+
+  if (!enabled)
+    return;
+
+  queue = ARR_CreateInstance(sizeof (SignInstance));
+  ARR_SetSize(queue, MAX_QUEUE_LENGTH);
+  queue_head = queue_tail = 0;
+
+  LOG(LOGS_INFO, "MS-SNTP authentication enabled");
+}
+
+/* ================================================== */
+
+void
+NSD_Finalise()
+{
+  if (!enabled)
+    return;
+  if (sock_fd != INVALID_SOCK_FD)
+    close_socket();
+  ARR_DestroyInstance(queue);
+}
+
+/* ================================================== */
+
+extern int NSD_GetAuthDelay(uint32_t key_id)
+{
+  return 1.0e9 * auth_delay;
+}
+
+/* ================================================== */
+
+int
+NSD_SignAndSendPacket(uint32_t key_id, NTP_Packet *packet, NTP_PacketInfo *info,
+                      NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr)
+{
+  SignInstance *inst;
+
+  if (!enabled) {
+    DEBUG_LOG("signd disabled");
+    return 0;
+  }
+
+  if (queue_head == NEXT_QUEUE_INDEX(queue_tail)) {
+    DEBUG_LOG("signd queue full");
+    return 0;
+  }
+
+  if (info->length != NTP_HEADER_LENGTH) {
+    DEBUG_LOG("Invalid packet length");
+    return 0;
+  }
+
+  if (!open_socket())
+    return 0;
+
+  inst = ARR_GetElement(queue, queue_tail);
+  inst->remote_addr = *remote_addr;
+  inst->local_addr = *local_addr;
+  inst->sent = 0;
+  inst->received = 0;
+  inst->request_length = offsetof(SigndRequest, packet_to_sign) + info->length;
+
+  /* The length field doesn't include itself */
+  inst->request.length = htonl(inst->request_length - sizeof (inst->request.length));
+  inst->request.version = htonl(SIGND_VERSION);
+  inst->request.op = htonl(SIGN_TO_CLIENT);
+  inst->request.packet_id = htons(queue_tail);
+  inst->request._pad = 0;
+  inst->request.key_id = htonl(key_id);
+
+  memcpy(&inst->request.packet_to_sign, packet, info->length);
+
+  /* Enable output if there was no pending request */
+  if (IS_QUEUE_EMPTY())
+    SCH_SetFileHandlerEvent(sock_fd, SCH_FILE_OUTPUT, 1);
+
+  queue_tail = NEXT_QUEUE_INDEX(queue_tail);
+
+  DEBUG_LOG("Packet added to signd queue (%u:%u)", queue_head, queue_tail);
+
+  return 1;
+}

ntp_signd.h

@@ -0,0 +1,45 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2016
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header for MS-SNTP authentication via Samba (ntp_signd) */
+
+#ifndef GOT_NTP_SIGND_H
+#define GOT_NTP_SIGND_H
+
+#include "addressing.h"
+#include "ntp.h"
+
+/* Initialisation function */
+extern void NSD_Initialise(void);
+
+/* Finalisation function */
+extern void NSD_Finalise(void);
+
+/* Function to get an estimate of delay due to signing */
+extern int NSD_GetAuthDelay(uint32_t key_id);
+
+/* Function to sign an NTP packet and send it */
+extern int NSD_SignAndSendPacket(uint32_t key_id, NTP_Packet *packet, NTP_PacketInfo *info,
+                                 NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr);
+
+#endif

ntp_sources.h

@@ -44,7 +44,9 @@ typedef enum {
   NSR_NoSuchSource, /* Remove - attempt to remove a source that is not known */
   NSR_AlreadyInUse, /* AddSource - attempt to add a source that is already known */ 
   NSR_TooManySources, /* AddSource - too many sources already present */
-  NSR_InvalidAF /* AddSource - attempt to add a source with invalid address family */
+  NSR_InvalidAF, /* AddSource - attempt to add a source with invalid address family */
+  NSR_InvalidName, /* AddSourceByName - attempt to add a source with invalid name */
+  NSR_UnresolvedName, /* AddSourceByName - name will be resolved later */
 } NSR_Status;
 
 /* Procedure to add a new server or peer source. */
@@ -52,8 +54,10 @@ extern NSR_Status NSR_AddSource(NTP_Remote_Address *remote_addr, NTP_Source_Type
 
 /* Procedure to add a new server, peer source, or pool of servers specified by
    name instead of address.  The name is resolved in exponentially increasing
-   intervals until it succeeds or fails with a non-temporary error. */
-extern void NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type, SourceParameters *params);
+   intervals until it succeeds or fails with a non-temporary error.  If the
+   name is an address, it is equivalent to NSR_AddSource(). */
+extern NSR_Status NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type,
+                                      SourceParameters *params);
 
 /* Function type for handlers to be called back when an attempt
  * (possibly unsuccessful) to resolve unresolved sources ends */
@@ -83,8 +87,25 @@ extern void NSR_HandleBadSource(IPAddr *address);
 /* Procedure to resolve all names again */
 extern void NSR_RefreshAddresses(void);
 
+/* Procedure to update the address of a source */
+extern NSR_Status NSR_UpdateSourceNtpAddress(NTP_Remote_Address *old_addr,
+                                             NTP_Remote_Address *new_addr);
+
+/* Procedure to get local reference ID corresponding to a source */
+extern uint32_t NSR_GetLocalRefid(IPAddr *address);
+
+/* Procedure to get the name of a source.  If the source doesn't have a name,
+   it returns a temporary string containing formatted address. */
+extern char *NSR_GetName(IPAddr *address);
+
 /* This routine is called by ntp_io when a new packet arrives off the network */
-extern void NSR_ProcessReceive(NTP_Packet *message, struct timeval *now, double now_err, NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr, int length);
+extern void NSR_ProcessRx(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr,
+                          NTP_Local_Timestamp *rx_ts, NTP_Packet *message, int length);
+
+/* This routine is called by ntp_io when a packet was sent to the network and
+   an accurate transmit timestamp was captured */
+extern void NSR_ProcessTx(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr,
+                          NTP_Local_Timestamp *tx_ts, NTP_Packet *message, int length);
 
 /* Initialisation function */
 extern void NSR_Initialise(void);
@@ -93,14 +114,9 @@ extern void NSR_Initialise(void);
 extern void NSR_Finalise(void);
 
 /* This routine is used to indicate that sources whose IP addresses
-   match a particular subnet should be set online again.  Returns a
-   flag indicating whether any hosts matched the address */
-extern int NSR_TakeSourcesOnline(IPAddr *mask, IPAddr *address);
-
-/* This routine is used to indicate that sources whose IP addresses
-   match a particular subnet should be set offline.  Returns a flag
-   indicating whether any hosts matched the address */
-extern int NSR_TakeSourcesOffline(IPAddr *mask, IPAddr *address);
+   match a particular subnet should be set online or offline.  It returns
+   a flag indicating whether any hosts matched the address. */
+extern int NSR_SetConnectivity(IPAddr *mask, IPAddr *address, SRC_Connectivity connectivity);
 
 extern int NSR_ModifyMinpoll(IPAddr *address, int new_minpoll);
 
@@ -118,8 +134,12 @@ extern int NSR_ModifyPolltarget(IPAddr *address, int new_poll_target);
 
 extern int NSR_InitiateSampleBurst(int n_good_samples, int n_total_samples, IPAddr *mask, IPAddr *address);
 
-extern void NSR_ReportSource(RPT_SourceReport *report, struct timeval *now);
+extern void NSR_ReportSource(RPT_SourceReport *report, struct timespec *now);
+
+extern int NSR_GetNTPReport(RPT_NTPReport *report);
 
 extern void NSR_GetActivityReport(RPT_ActivityReport *report);
 
+extern void NSR_DumpAuthData(void);
+
 #endif /* GOT_NTP_SOURCES_H */

nts_ke.h

@@ -0,0 +1,79 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for the NTS Key Establishment protocol
+  */
+
+#ifndef GOT_NTS_KE_H
+#define GOT_NTS_KE_H
+
+#include "siv.h"
+
+#define NKE_RECORD_CRITICAL_BIT         (1U << 15)
+#define NKE_RECORD_END_OF_MESSAGE       0
+#define NKE_RECORD_NEXT_PROTOCOL        1
+#define NKE_RECORD_ERROR                2
+#define NKE_RECORD_WARNING              3
+#define NKE_RECORD_AEAD_ALGORITHM       4
+#define NKE_RECORD_COOKIE               5
+#define NKE_RECORD_NTPV4_SERVER_NEGOTIATION 6
+#define NKE_RECORD_NTPV4_PORT_NEGOTIATION 7
+
+#define NKE_NEXT_PROTOCOL_NTPV4         0
+
+#define NKE_ERROR_UNRECOGNIZED_CRITICAL_RECORD 0
+#define NKE_ERROR_BAD_REQUEST           1
+#define NKE_ERROR_INTERNAL_SERVER_ERROR 2
+
+#define NKE_ALPN_NAME                   "ntske/1"
+#define NKE_EXPORTER_LABEL              "EXPORTER-network-time-security"
+#define NKE_EXPORTER_CONTEXT_C2S        "\x0\x0\x0\xf\x0"
+#define NKE_EXPORTER_CONTEXT_S2C        "\x0\x0\x0\xf\x1"
+
+#define NKE_MAX_MESSAGE_LENGTH          16384
+#define NKE_MAX_RECORD_BODY_LENGTH      256
+#define NKE_MAX_COOKIE_LENGTH           256
+#define NKE_MAX_COOKIES                 8
+#define NKE_MAX_KEY_LENGTH SIV_MAX_KEY_LENGTH
+
+#define NKE_RETRY_FACTOR2_CONNECT       4
+#define NKE_RETRY_FACTOR2_TLS           10
+#define NKE_MAX_RETRY_INTERVAL2         19
+
+typedef struct {
+  int length;
+  unsigned char key[NKE_MAX_KEY_LENGTH];
+} NKE_Key;
+
+typedef struct {
+  SIV_Algorithm algorithm;
+  NKE_Key c2s;
+  NKE_Key s2c;
+} NKE_Context;
+
+typedef struct {
+  int length;
+  unsigned char cookie[NKE_MAX_COOKIE_LENGTH];
+} NKE_Cookie;
+
+#endif

nts_ke_client.c

@@ -0,0 +1,400 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  NTS-KE client
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "nts_ke_client.h"
+
+#include "conf.h"
+#include "logging.h"
+#include "memory.h"
+#include "nameserv_async.h"
+#include "nts_ke_session.h"
+#include "siv.h"
+#include "socket.h"
+#include "util.h"
+
+#define CLIENT_TIMEOUT 16.0
+
+struct NKC_Instance_Record {
+  char *name;
+  IPSockAddr address;
+  NKSN_Instance session;
+  int destroying;
+  int got_response;
+  int resolving_name;
+
+  NKE_Context context;
+  NKE_Cookie cookies[NKE_MAX_COOKIES];
+  int num_cookies;
+  char server_name[NKE_MAX_RECORD_BODY_LENGTH + 1];
+  IPSockAddr ntp_address;
+};
+
+/* ================================================== */
+
+static void *client_credentials;
+
+/* ================================================== */
+
+static void
+name_resolve_handler(DNS_Status status, int n_addrs, IPAddr *ip_addrs, void *arg)
+{
+  NKC_Instance inst = arg;
+  int i;
+
+  inst->resolving_name = 0;
+
+  if (inst->destroying) {
+    NKC_DestroyInstance(inst);
+    return;
+  }
+
+  if (status != DNS_Success || n_addrs < 1) {
+    LOG(LOGS_ERR, "Could not resolve NTP server %s from %s", inst->server_name, inst->name);
+    /* Force restart */
+    inst->got_response = 0;
+    return;
+  }
+
+  inst->ntp_address.ip_addr = ip_addrs[0];
+
+  /* Prefer an address of the same family as NTS-KE */
+  for (i = 0; i < n_addrs; i++) {
+    DEBUG_LOG("%s resolved to %s", inst->server_name, UTI_IPToString(&ip_addrs[i]));
+    if (ip_addrs[i].family == inst->address.ip_addr.family) {
+      inst->ntp_address.ip_addr = ip_addrs[i];
+      break;
+    }
+  }
+}
+
+/* ================================================== */
+
+static int
+prepare_request(NKC_Instance inst)
+{
+  NKSN_Instance session = inst->session;
+  uint16_t datum;
+
+  NKSN_BeginMessage(session);
+
+  datum = htons(NKE_NEXT_PROTOCOL_NTPV4);
+  if (!NKSN_AddRecord(session, 1, NKE_RECORD_NEXT_PROTOCOL, &datum, sizeof (datum)))
+    return 0;
+
+  datum = htons(AEAD_AES_SIV_CMAC_256);
+  if (!NKSN_AddRecord(session, 1, NKE_RECORD_AEAD_ALGORITHM, &datum, sizeof (datum)))
+    return 0;
+
+  if (!NKSN_EndMessage(session))
+    return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+process_response(NKC_Instance inst)
+{
+  int next_protocol = -1, aead_algorithm = -1, error = 0;
+  int i, critical, type, length;
+  uint16_t data[NKE_MAX_COOKIE_LENGTH / sizeof (uint16_t)];
+
+  assert(NKE_MAX_COOKIE_LENGTH % sizeof (uint16_t) == 0);
+  assert(sizeof (uint16_t) == 2);
+
+  inst->num_cookies = 0;
+  inst->ntp_address.ip_addr.family = IPADDR_UNSPEC;
+  inst->ntp_address.port = 0;
+  inst->server_name[0] = '\0';
+
+  while (!error) {
+    if (!NKSN_GetRecord(inst->session, &critical, &type, &length, &data, sizeof (data)))
+      break;
+
+    switch (type) {
+      case NKE_RECORD_NEXT_PROTOCOL:
+        if (!critical || length != 2 || ntohs(data[0]) != NKE_NEXT_PROTOCOL_NTPV4) {
+          DEBUG_LOG("Unexpected NTS-KE next protocol");
+          error = 1;
+          break;
+        }
+        next_protocol = NKE_NEXT_PROTOCOL_NTPV4;
+        break;
+      case NKE_RECORD_AEAD_ALGORITHM:
+        if (length != 2 || ntohs(data[0]) != AEAD_AES_SIV_CMAC_256) {
+          DEBUG_LOG("Unexpected NTS-KE AEAD algorithm");
+          error = 1;
+          break;
+        }
+        aead_algorithm = AEAD_AES_SIV_CMAC_256;
+        inst->context.algorithm = aead_algorithm;
+        break;
+      case NKE_RECORD_ERROR:
+        if (length == 2)
+          DEBUG_LOG("NTS-KE error %d", ntohs(data[0]));
+        error = 1;
+        break;
+      case NKE_RECORD_WARNING:
+        if (length == 2)
+          DEBUG_LOG("NTS-KE warning %d", ntohs(data[0]));
+        error = 1;
+        break;
+      case NKE_RECORD_COOKIE:
+        DEBUG_LOG("Got cookie #%d length=%d", inst->num_cookies + 1, length);
+        assert(NKE_MAX_COOKIE_LENGTH == sizeof (inst->cookies[inst->num_cookies].cookie));
+        if (length <= NKE_MAX_COOKIE_LENGTH && inst->num_cookies < NKE_MAX_COOKIES) {
+          inst->cookies[inst->num_cookies].length = length;
+          memcpy(inst->cookies[inst->num_cookies].cookie, data, length);
+          inst->num_cookies++;
+        }
+        break;
+      case NKE_RECORD_NTPV4_SERVER_NEGOTIATION:
+        if (length < 1 || length >= sizeof (inst->server_name)) {
+          DEBUG_LOG("Invalid server name");
+          error = 1;
+          break;
+        }
+
+        memcpy(inst->server_name, data, length);
+        inst->server_name[length] = '\0';
+
+        /* Make sure the name is printable and has no spaces */
+        for (i = 0; i < length && isgraph(inst->server_name[i]); i++)
+          ;
+        if (i != length) {
+          DEBUG_LOG("Invalid server name");
+          error = 1;
+          break;
+        }
+
+        DEBUG_LOG("Negotiated server %s", inst->server_name);
+        break;
+      case NKE_RECORD_NTPV4_PORT_NEGOTIATION:
+        if (length != 2) {
+          DEBUG_LOG("Invalid port");
+          error = 1;
+          break;
+        }
+        inst->ntp_address.port = ntohs(data[0]);
+        DEBUG_LOG("Negotiated port %d", inst->ntp_address.port);
+        break;
+      default:
+        DEBUG_LOG("Unknown record type=%d length=%d critical=%d", type, length, critical);
+        if (critical)
+          error = 1;
+    }
+  }
+
+  DEBUG_LOG("NTS-KE response: error=%d next=%d aead=%d",
+            error, next_protocol, aead_algorithm);
+
+  if (error || inst->num_cookies == 0 ||
+      next_protocol != NKE_NEXT_PROTOCOL_NTPV4 ||
+      aead_algorithm != AEAD_AES_SIV_CMAC_256)
+    return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+handle_message(void *arg)
+{
+  NKC_Instance inst = arg;
+
+  if (!process_response(inst)) {
+    LOG(LOGS_ERR, "Received invalid NTS-KE response from %s", inst->name);
+    return 0;
+  }
+
+  if (!NKSN_GetKeys(inst->session, inst->context.algorithm,
+                    &inst->context.c2s, &inst->context.s2c))
+    return 0;
+
+  if (inst->server_name[0] != '\0') {
+    if (inst->resolving_name)
+      return 0;
+    if (!UTI_StringToIP(inst->server_name, &inst->ntp_address.ip_addr)) {
+      DNS_Name2IPAddressAsync(inst->server_name, name_resolve_handler, inst);
+      inst->resolving_name = 1;
+    }
+  }
+
+  inst->got_response = 1;
+
+  return 1;
+}
+
+/* ================================================== */
+
+void
+NKC_Initialise(void)
+{
+  client_credentials = NULL;
+}
+
+/* ================================================== */
+
+void
+NKC_Finalise(void)
+{
+  if (client_credentials)
+    NKSN_DestroyCertCredentials(client_credentials);
+}
+
+/* ================================================== */
+
+NKC_Instance
+NKC_CreateInstance(IPSockAddr *address, const char *name)
+{
+  NKC_Instance inst;
+
+  inst = MallocNew(struct NKC_Instance_Record);
+
+  inst->address = *address;
+  inst->name = Strdup(name);
+  inst->session = NKSN_CreateInstance(0, inst->name, handle_message, inst);
+  inst->resolving_name = 0;
+  inst->destroying = 0;
+  inst->got_response = 0;
+
+  /* Create the credentials with the first client instance and share them
+     with other instances */
+  if (!client_credentials)
+    client_credentials = NKSN_CreateCertCredentials(NULL, NULL, CNF_GetNtsTrustedCertFile());
+
+  return inst;
+}
+
+/* ================================================== */
+
+void
+NKC_DestroyInstance(NKC_Instance inst)
+{
+  /* If the resolver is running, destroy the instance later when finished */
+  if (inst->resolving_name) {
+    inst->destroying = 1;
+    return;
+  }
+
+  NKSN_DestroyInstance(inst->session);
+
+  Free(inst->name);
+  Free(inst);
+}
+
+/* ================================================== */
+
+int
+NKC_Start(NKC_Instance inst)
+{
+  IPSockAddr local_addr;
+  char label[512];
+  int sock_fd;
+
+  assert(!NKC_IsActive(inst));
+
+  if (!client_credentials) {
+    DEBUG_LOG("Missing client credentials");
+    return 0;
+  }
+
+  /* Follow the bindacqaddress setting */
+  CNF_GetBindAcquisitionAddress(inst->address.ip_addr.family, &local_addr.ip_addr);
+  if (local_addr.ip_addr.family != inst->address.ip_addr.family)
+    SCK_GetAnyLocalIPAddress(inst->address.ip_addr.family, &local_addr.ip_addr);
+
+  local_addr.port = 0;
+
+  sock_fd = SCK_OpenTcpSocket(&inst->address, &local_addr, 0);
+  if (sock_fd < 0)
+    return 0;
+
+  /* Make a label containing both the address and name of the server */
+  if (snprintf(label, sizeof (label), "%s (%s)",
+               UTI_IPSockAddrToString(&inst->address), inst->name) >= sizeof (label))
+    ;
+
+  /* Start a NTS-KE session */
+  if (!NKSN_StartSession(inst->session, sock_fd, label, client_credentials, CLIENT_TIMEOUT)) {
+    SCK_CloseSocket(sock_fd);
+    return 0;
+  }
+
+  /* Send a request */
+  if (!prepare_request(inst)) {
+    DEBUG_LOG("Could not prepare NTS-KE request");
+    NKSN_StopSession(inst->session);
+    return 0;
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NKC_IsActive(NKC_Instance inst)
+{
+  return !NKSN_IsStopped(inst->session) || inst->resolving_name;
+}
+
+/* ================================================== */
+
+int
+NKC_GetNtsData(NKC_Instance inst, NKE_Context *context,
+               NKE_Cookie *cookies, int *num_cookies, int max_cookies,
+               IPSockAddr *ntp_address)
+{
+  int i;
+
+  if (!inst->got_response || inst->resolving_name)
+    return 0;
+
+  *context = inst->context;
+
+  for (i = 0; i < inst->num_cookies && i < max_cookies; i++)
+    cookies[i] = inst->cookies[i];
+  *num_cookies = i;
+
+  *ntp_address = inst->ntp_address;
+
+  return i;
+}
+
+/* ================================================== */
+
+int
+NKC_GetRetryFactor(NKC_Instance inst)
+{
+  return NKSN_GetRetryFactor(inst->session);
+}

nts_ke_client.h

@@ -0,0 +1,60 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for the NTS-KE client
+  */
+
+#ifndef GOT_NTS_KE_CLIENT_H
+#define GOT_NTS_KE_CLIENT_H
+
+#include "addressing.h"
+#include "nts_ke.h"
+
+typedef struct NKC_Instance_Record *NKC_Instance;
+
+/* Init and fini functions */
+extern void NKC_Initialise(void);
+extern void NKC_Finalise(void);
+
+/* Create a client NTS-KE instance */
+extern NKC_Instance NKC_CreateInstance(IPSockAddr *address, const char *name);
+
+/* Destroy an instance */
+extern void NKC_DestroyInstance(NKC_Instance inst);
+
+/* Connect to the server, start an NTS-KE session, send an NTS-KE request, and
+   process the response (asynchronously) */
+extern int NKC_Start(NKC_Instance inst);
+
+/* Check if the client is still running */
+extern int NKC_IsActive(NKC_Instance inst);
+
+/* Get the NTS data if the session was successful */
+extern int NKC_GetNtsData(NKC_Instance inst, NKE_Context *context,
+                          NKE_Cookie *cookies, int *num_cookies, int max_cookies,
+                          IPSockAddr *ntp_address);
+
+/* Get a factor to calculate retry interval (in log2 seconds) */
+extern int NKC_GetRetryFactor(NKC_Instance inst);
+
+#endif

nts_ke_server.c

@@ -0,0 +1,857 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  NTS-KE server
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "nts_ke_server.h"
+
+#include "array.h"
+#include "conf.h"
+#include "clientlog.h"
+#include "logging.h"
+#include "memory.h"
+#include "ntp_core.h"
+#include "nts_ke_session.h"
+#include "siv.h"
+#include "socket.h"
+#include "sched.h"
+#include "sys.h"
+#include "util.h"
+
+#define SERVER_TIMEOUT 2.0
+
+#define SERVER_COOKIE_SIV AEAD_AES_SIV_CMAC_256
+#define SERVER_COOKIE_NONCE_LENGTH 16
+
+#define KEY_ID_INDEX_BITS 2
+#define MAX_SERVER_KEYS (1U << KEY_ID_INDEX_BITS)
+#define FUTURE_KEYS 1
+
+#define DUMP_FILENAME "ntskeys"
+#define DUMP_IDENTIFIER "NKS0\n"
+
+#define INVALID_SOCK_FD (-7)
+
+typedef struct {
+  uint32_t key_id;
+  uint8_t nonce[SERVER_COOKIE_NONCE_LENGTH];
+} ServerCookieHeader;
+
+typedef struct {
+  uint32_t id;
+  unsigned char key[SIV_MAX_KEY_LENGTH];
+  SIV_Instance siv;
+} ServerKey;
+
+typedef struct {
+  uint32_t key_id;
+  unsigned char key[SIV_MAX_KEY_LENGTH];
+  IPAddr client_addr;
+  uint16_t client_port;
+  uint16_t _pad;
+} HelperRequest;
+
+/* ================================================== */
+
+static ServerKey server_keys[MAX_SERVER_KEYS];
+static int current_server_key;
+static double last_server_key_ts;
+static int key_rotation_interval;
+
+static int server_sock_fd4;
+static int server_sock_fd6;
+
+static int helper_sock_fd;
+
+static int initialised = 0;
+
+/* Array of NKSN instances */
+static ARR_Instance sessions;
+static void *server_credentials;
+
+/* ================================================== */
+
+static int handle_message(void *arg);
+
+/* ================================================== */
+
+static int
+handle_client(int sock_fd, IPSockAddr *addr)
+{
+  NKSN_Instance inst, *instp;
+  int i;
+
+  if (sock_fd > FD_SETSIZE / 2) {
+    DEBUG_LOG("Rejected connection from %s (%s)",
+              UTI_IPSockAddrToString(addr), "too many descriptors");
+    return 0;
+  }
+
+  /* Find a slot which is free or has a stopped session */
+  for (i = 0, inst = NULL; i < ARR_GetSize(sessions); i++) {
+    instp = ARR_GetElement(sessions, i);
+    if (!*instp) {
+      /* NULL handler arg will be replaced with the session instance */
+      inst = NKSN_CreateInstance(1, NULL, handle_message, NULL);
+      *instp = inst;
+      break;
+    } else if (NKSN_IsStopped(*instp)) {
+      inst = *instp;
+      break;
+    }
+  }
+
+  if (!inst) {
+    DEBUG_LOG("Rejected connection from %s (%s)",
+              UTI_IPSockAddrToString(addr), "too many connections");
+    return 0;
+  }
+
+  if (!NKSN_StartSession(inst, sock_fd, UTI_IPSockAddrToString(addr),
+                         server_credentials, SERVER_TIMEOUT))
+    return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static void
+handle_helper_request(int fd, int event, void *arg)
+{
+  SCK_Message *message;
+  HelperRequest *req;
+  IPSockAddr client_addr;
+  int sock_fd;
+
+  message = SCK_ReceiveMessage(fd, SCK_FLAG_MSG_DESCRIPTOR);
+  if (!message)
+    return;
+
+  sock_fd = message->descriptor;
+  if (sock_fd < 0) {
+    /* Message with no descriptor is a shutdown command */
+    SCH_QuitProgram();
+    return;
+  }
+
+  if (message->length != sizeof (HelperRequest)) {
+    DEBUG_LOG("Unexpected message length");
+    SCK_CloseSocket(sock_fd);
+    return;
+  }
+
+  req = message->data;
+
+  /* Extract the server key and client address from the request */
+  server_keys[current_server_key].id = ntohl(req->key_id);
+  memcpy(server_keys[current_server_key].key, req->key,
+         sizeof (server_keys[current_server_key].key));
+  UTI_IPNetworkToHost(&req->client_addr, &client_addr.ip_addr);
+  client_addr.port = ntohs(req->client_port);
+
+  if (!SIV_SetKey(server_keys[current_server_key].siv, server_keys[current_server_key].key,
+                  SIV_GetKeyLength(SERVER_COOKIE_SIV)))
+    assert(0);
+
+  if (!handle_client(sock_fd, &client_addr)) {
+    SCK_CloseSocket(sock_fd);
+    return;
+  }
+
+  DEBUG_LOG("Accepted helper request fd=%d", sock_fd);
+}
+
+/* ================================================== */
+
+static void
+accept_connection(int server_fd, int event, void *arg)
+{
+  SCK_Message message;
+  IPSockAddr addr;
+  int log_index, sock_fd;
+  struct timespec now;
+
+  sock_fd = SCK_AcceptConnection(server_fd, &addr);
+  if (sock_fd < 0)
+    return;
+
+  if (!NCR_CheckAccessRestriction(&addr.ip_addr)) {
+    DEBUG_LOG("Rejected connection from %s (%s)",
+              UTI_IPSockAddrToString(&addr), "access denied");
+    SCK_CloseSocket(sock_fd);
+    return;
+  }
+
+  SCH_GetLastEventTime(&now, NULL, NULL);
+  log_index = CLG_LogNTPAccess(&addr.ip_addr, &now);
+  if (log_index >= 0 && CLG_LimitNTPResponseRate(log_index)) {
+    DEBUG_LOG("Rejected connection from %s (%s)",
+              UTI_IPSockAddrToString(&addr), "rate limit");
+    SCK_CloseSocket(sock_fd);
+    return;
+  }
+
+  /* Pass the socket to a helper process if enabled.  Otherwise, handle the
+     client in the main process. */
+  if (helper_sock_fd != INVALID_SOCK_FD) {
+    HelperRequest req;
+
+    /* Include the current server key and client address in the request */
+    memset(&req, 0, sizeof (req));
+    req.key_id = htonl(server_keys[current_server_key].id);
+    memcpy(req.key, server_keys[current_server_key].key, sizeof (req.key));
+    UTI_IPHostToNetwork(&addr.ip_addr, &req.client_addr);
+    req.client_port = htons(addr.port);
+
+    SCK_InitMessage(&message, SCK_ADDR_UNSPEC);
+    message.data = &req;
+    message.length = sizeof (req);
+    message.descriptor = sock_fd;
+
+    if (!SCK_SendMessage(helper_sock_fd, &message, SCK_FLAG_MSG_DESCRIPTOR)) {
+      SCK_CloseSocket(sock_fd);
+      return;
+    }
+
+    SCK_CloseSocket(sock_fd);
+  } else {
+    if (!handle_client(sock_fd, &addr)) {
+      SCK_CloseSocket(sock_fd);
+      return;
+    }
+  }
+
+  DEBUG_LOG("Accepted connection from %s fd=%d", UTI_IPSockAddrToString(&addr), sock_fd);
+}
+
+/* ================================================== */
+
+static int
+open_socket(int family, int port)
+{
+  IPSockAddr local_addr;
+  int sock_fd;
+
+  if (!SCK_IsFamilySupported(family))
+    return INVALID_SOCK_FD;
+
+  CNF_GetBindAddress(family, &local_addr.ip_addr);
+
+  if (local_addr.ip_addr.family != family)
+    SCK_GetAnyLocalIPAddress(family, &local_addr.ip_addr);
+
+  local_addr.port = port;
+
+  sock_fd = SCK_OpenTcpSocket(NULL, &local_addr, 0);
+  if (sock_fd < 0) {
+    LOG(LOGS_ERR, "Could not open NTS-KE socket on %s", UTI_IPSockAddrToString(&local_addr));
+    return INVALID_SOCK_FD;
+  }
+
+  if (!SCK_ListenOnSocket(sock_fd, CNF_GetNtsServerConnections())) {
+    SCK_CloseSocket(sock_fd);
+    return INVALID_SOCK_FD;
+  }
+
+  SCH_AddFileHandler(sock_fd, SCH_FILE_INPUT, accept_connection, NULL);
+
+  return sock_fd;
+}
+
+/* ================================================== */
+
+static void
+helper_signal(int x)
+{
+  SCH_QuitProgram();
+}
+
+/* ================================================== */
+
+static int
+prepare_response(NKSN_Instance session, int error, int next_protocol, int aead_algorithm)
+{
+  NKE_Context context;
+  NKE_Cookie cookie;
+  char *ntp_server;
+  uint16_t datum;
+  int i;
+
+  DEBUG_LOG("NTS KE response: error=%d next=%d aead=%d", error, next_protocol, aead_algorithm);
+
+  NKSN_BeginMessage(session);
+
+  if (error >= 0) {
+    datum = htons(error);
+    if (!NKSN_AddRecord(session, 1, NKE_RECORD_ERROR, &datum, sizeof (datum)))
+      return 0;
+  } else {
+    datum = htons(next_protocol);
+    if (!NKSN_AddRecord(session, 1, NKE_RECORD_NEXT_PROTOCOL, &datum, sizeof (datum)))
+      return 0;
+
+    datum = htons(aead_algorithm);
+    if (!NKSN_AddRecord(session, 1, NKE_RECORD_AEAD_ALGORITHM, &datum, sizeof (datum)))
+      return 0;
+
+    if (CNF_GetNTPPort() != NTP_PORT) {
+      datum = htons(CNF_GetNTPPort());
+      if (!NKSN_AddRecord(session, 1, NKE_RECORD_NTPV4_PORT_NEGOTIATION, &datum, sizeof (datum)))
+        return 0;
+    }
+
+    ntp_server = CNF_GetNtsNtpServer();
+    if (ntp_server) {
+      if (!NKSN_AddRecord(session, 1, NKE_RECORD_NTPV4_SERVER_NEGOTIATION,
+                          ntp_server, strlen(ntp_server)))
+        return 0;
+    }
+
+    context.algorithm = aead_algorithm;
+
+    if (!NKSN_GetKeys(session, aead_algorithm, &context.c2s, &context.s2c))
+      return 0;
+
+    for (i = 0; i < NKE_MAX_COOKIES; i++) {
+      if (!NKS_GenerateCookie(&context, &cookie))
+        return 0;
+      if (!NKSN_AddRecord(session, 0, NKE_RECORD_COOKIE, cookie.cookie, cookie.length))
+        return 0;
+    }
+  }
+
+  if (!NKSN_EndMessage(session))
+    return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+process_request(NKSN_Instance session)
+{
+  int next_protocol = -1, aead_algorithm = -1, error = -1;
+  int i, critical, type, length;
+  uint16_t data[NKE_MAX_RECORD_BODY_LENGTH / sizeof (uint16_t)];
+
+  assert(NKE_MAX_RECORD_BODY_LENGTH % sizeof (uint16_t) == 0);
+  assert(sizeof (uint16_t) == 2);
+
+  while (error == -1) {
+    if (!NKSN_GetRecord(session, &critical, &type, &length, &data, sizeof (data)))
+      break;
+
+    switch (type) {
+      case NKE_RECORD_NEXT_PROTOCOL:
+        if (!critical || length < 2 || length % 2 != 0) {
+          error = NKE_ERROR_BAD_REQUEST;
+          break;
+        }
+        for (i = 0; i < MIN(length, sizeof (data)) / 2; i++) {
+          if (ntohs(data[i]) == NKE_NEXT_PROTOCOL_NTPV4)
+            next_protocol = NKE_NEXT_PROTOCOL_NTPV4;
+        }
+        break;
+      case NKE_RECORD_AEAD_ALGORITHM:
+        if (length < 2 || length % 2 != 0) {
+          error = NKE_ERROR_BAD_REQUEST;
+          break;
+        }
+        for (i = 0; i < MIN(length, sizeof (data)) / 2; i++) {
+          if (ntohs(data[i]) == AEAD_AES_SIV_CMAC_256)
+            aead_algorithm = AEAD_AES_SIV_CMAC_256;
+        }
+        break;
+      case NKE_RECORD_ERROR:
+      case NKE_RECORD_WARNING:
+      case NKE_RECORD_COOKIE:
+        error = NKE_ERROR_BAD_REQUEST;
+        break;
+      default:
+        if (critical)
+          error = NKE_ERROR_UNRECOGNIZED_CRITICAL_RECORD;
+    }
+  }
+
+  if (aead_algorithm < 0 || next_protocol < 0)
+    error = NKE_ERROR_BAD_REQUEST;
+
+  if (!prepare_response(session, error, next_protocol, aead_algorithm))
+    return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+handle_message(void *arg)
+{
+  NKSN_Instance session = arg;
+
+  return process_request(session);
+}
+
+/* ================================================== */
+
+static void
+generate_key(int index)
+{
+  int key_length;
+
+  assert(index < MAX_SERVER_KEYS);
+
+  key_length = SIV_GetKeyLength(SERVER_COOKIE_SIV);
+  if (key_length > sizeof (server_keys[index].key))
+    assert(0);
+
+  UTI_GetRandomBytesUrandom(server_keys[index].key, key_length);
+  if (!SIV_SetKey(server_keys[index].siv, server_keys[index].key, key_length))
+    assert(0);
+
+  UTI_GetRandomBytes(&server_keys[index].id, sizeof (server_keys[index].id));
+
+  server_keys[index].id &= -1U << KEY_ID_INDEX_BITS;
+  server_keys[index].id |= index;
+
+  DEBUG_LOG("Generated server key %"PRIX32, server_keys[index].id);
+
+  last_server_key_ts = SCH_GetLastEventMonoTime();
+}
+
+/* ================================================== */
+
+static void
+save_keys(void)
+{
+  char buf[SIV_MAX_KEY_LENGTH * 2 + 1], *dump_dir;
+  int i, index, key_length;
+  double last_key_age;
+  FILE *f;
+
+  /* Don't save the keys if rotation is disabled to enable an external
+     management of the keys (e.g. share them with another server) */
+  if (key_rotation_interval == 0)
+    return;
+
+  dump_dir = CNF_GetNtsDumpDir();
+  if (!dump_dir)
+    return;
+
+  f = UTI_OpenFile(dump_dir, DUMP_FILENAME, ".tmp", 'w', 0600);
+  if (!f)
+    return;
+
+  key_length = SIV_GetKeyLength(SERVER_COOKIE_SIV);
+  last_key_age = SCH_GetLastEventMonoTime() - last_server_key_ts;
+
+  if (fprintf(f, "%s%d %.1f\n", DUMP_IDENTIFIER, SERVER_COOKIE_SIV, last_key_age) < 0)
+    goto error;
+
+  for (i = 0; i < MAX_SERVER_KEYS; i++) {
+    index = (current_server_key + i + 1 + FUTURE_KEYS) % MAX_SERVER_KEYS;
+
+    if (key_length > sizeof (server_keys[index].key) ||
+        !UTI_BytesToHex(server_keys[index].key, key_length, buf, sizeof (buf)) ||
+        fprintf(f, "%08"PRIX32" %s\n", server_keys[index].id, buf) < 0)
+      goto error;
+  }
+
+  fclose(f);
+
+  if (!UTI_RenameTempFile(dump_dir, DUMP_FILENAME, ".tmp", NULL)) {
+    if (!UTI_RemoveFile(dump_dir, DUMP_FILENAME, ".tmp"))
+      ;
+  }
+
+  return;
+
+error:
+  DEBUG_LOG("Could not %s server keys", "save");
+  fclose(f);
+
+  if (!UTI_RemoveFile(dump_dir, DUMP_FILENAME, NULL))
+    ;
+}
+
+/* ================================================== */
+
+#define MAX_WORDS 2
+
+static void
+load_keys(void)
+{
+  char *dump_dir, line[1024], *words[MAX_WORDS];
+  int i, index, key_length, algorithm;
+  double key_age;
+  FILE *f;
+  uint32_t id;
+
+  dump_dir = CNF_GetNtsDumpDir();
+  if (!dump_dir)
+    return;
+
+  f = UTI_OpenFile(dump_dir, DUMP_FILENAME, NULL, 'r', 0);
+  if (!f)
+    return;
+
+  if (!fgets(line, sizeof (line), f) || strcmp(line, DUMP_IDENTIFIER) != 0 ||
+      !fgets(line, sizeof (line), f) || UTI_SplitString(line, words, MAX_WORDS) != 2 ||
+        sscanf(words[0], "%d", &algorithm) != 1 || algorithm != SERVER_COOKIE_SIV ||
+        sscanf(words[1], "%lf", &key_age) != 1)
+    goto error;
+
+  key_length = SIV_GetKeyLength(SERVER_COOKIE_SIV);
+  last_server_key_ts = SCH_GetLastEventMonoTime() - MAX(key_age, 0.0);
+
+  for (i = 0; i < MAX_SERVER_KEYS && fgets(line, sizeof (line), f); i++) {
+    if (UTI_SplitString(line, words, MAX_WORDS) != 2 ||
+        sscanf(words[0], "%"PRIX32, &id) != 1)
+      goto error;
+
+    index = id % MAX_SERVER_KEYS;
+
+    if (UTI_HexToBytes(words[1], server_keys[index].key,
+                       sizeof (server_keys[index].key)) != key_length)
+      goto error;
+
+    server_keys[index].id = id;
+    if (!SIV_SetKey(server_keys[index].siv, server_keys[index].key, key_length))
+      assert(0);
+
+    DEBUG_LOG("Loaded key %"PRIX32, id);
+
+    current_server_key = (index + MAX_SERVER_KEYS - FUTURE_KEYS) % MAX_SERVER_KEYS;
+  }
+
+  fclose(f);
+
+  return;
+
+error:
+  DEBUG_LOG("Could not %s server keys", "load");
+  fclose(f);
+}
+
+/* ================================================== */
+
+static void
+key_timeout(void *arg)
+{
+  current_server_key = (current_server_key + 1) % MAX_SERVER_KEYS;
+  generate_key((current_server_key + FUTURE_KEYS) % MAX_SERVER_KEYS);
+  save_keys();
+
+  SCH_AddTimeoutByDelay(key_rotation_interval, key_timeout, NULL);
+}
+
+/* ================================================== */
+
+static void
+start_helper(int id, int scfilter_level, int main_fd, int helper_fd)
+{
+  pid_t pid;
+
+  pid = fork();
+
+  if (pid < 0)
+    LOG_FATAL("fork() failed : %s", strerror(errno));
+
+  if (pid > 0)
+    return;
+
+  SCK_CloseSocket(main_fd);
+
+  LOG_CloseParentFd();
+  SCH_Reset();
+  SCH_AddFileHandler(helper_fd, SCH_FILE_INPUT, handle_helper_request, NULL);
+  UTI_SetQuitSignalsHandler(helper_signal, 1);
+  if (scfilter_level != 0)
+    SYS_EnableSystemCallFilter(scfilter_level, SYS_NTSKE_HELPER);
+
+  initialised = 1;
+
+  DEBUG_LOG("NTS-KE helper #%d started", id);
+
+  SCH_MainLoop();
+
+  NKS_Finalise();
+
+  DEBUG_LOG("NTS-KE helper #%d exiting", id);
+
+  exit(0);
+}
+
+/* ================================================== */
+
+void
+NKS_Initialise(int scfilter_level)
+{
+  char *cert, *key;
+  int i, processes;
+  double key_delay;
+
+  server_sock_fd4 = INVALID_SOCK_FD;
+  server_sock_fd6 = INVALID_SOCK_FD;
+  helper_sock_fd = INVALID_SOCK_FD;
+
+  cert = CNF_GetNtsServerCertFile();
+  key = CNF_GetNtsServerKeyFile();
+
+  if (!cert || !key)
+    return;
+
+  server_credentials = NKSN_CreateCertCredentials(cert, key, NULL);
+  if (!server_credentials)
+    return;
+
+  sessions = ARR_CreateInstance(sizeof (NKSN_Instance));
+  for (i = 0; i < CNF_GetNtsServerConnections(); i++)
+    *(NKSN_Instance *)ARR_GetNewElement(sessions) = NULL;
+  for (i = 0; i < MAX_SERVER_KEYS; i++)
+    server_keys[i].siv = NULL;
+
+  server_sock_fd4 = open_socket(IPADDR_INET4, CNF_GetNtsServerPort());
+  server_sock_fd6 = open_socket(IPADDR_INET6, CNF_GetNtsServerPort());
+
+  for (i = 0; i < MAX_SERVER_KEYS; i++) {
+    server_keys[i].siv = SIV_CreateInstance(SERVER_COOKIE_SIV);
+    generate_key(i);
+  }
+
+  current_server_key = MAX_SERVER_KEYS - 1;
+
+  load_keys();
+
+  key_rotation_interval = MAX(CNF_GetNtsRotate(), 0);
+
+  if (key_rotation_interval > 0) {
+    key_delay = key_rotation_interval - (SCH_GetLastEventMonoTime() - last_server_key_ts);
+    SCH_AddTimeoutByDelay(MAX(key_delay, 0.0), key_timeout, NULL);
+  }
+
+  processes = CNF_GetNtsServerProcesses();
+
+  if (processes > 0) {
+    int sock_fd1, sock_fd2;
+
+    sock_fd1 = SCK_OpenUnixSocketPair(0, &sock_fd2);
+    if (sock_fd1 < 0)
+      LOG_FATAL("Could not open socket pair");
+
+    for (i = 0; i < processes; i++)
+      start_helper(i + 1, scfilter_level, sock_fd1, sock_fd2);
+
+    SCK_CloseSocket(sock_fd2);
+    helper_sock_fd = sock_fd1;
+  }
+
+  initialised = 1;
+}
+
+/* ================================================== */
+
+void
+NKS_Finalise(void)
+{
+  int i;
+
+  if (!initialised)
+    return;
+
+  if (helper_sock_fd != INVALID_SOCK_FD) {
+    for (i = 0; i < CNF_GetNtsServerProcesses(); i++) {
+      if (!SCK_Send(helper_sock_fd, "", 1, 0))
+        ;
+    }
+    SCK_CloseSocket(helper_sock_fd);
+  }
+  if (server_sock_fd4 != INVALID_SOCK_FD)
+    SCK_CloseSocket(server_sock_fd4);
+  if (server_sock_fd6 != INVALID_SOCK_FD)
+    SCK_CloseSocket(server_sock_fd6);
+
+  save_keys();
+  for (i = 0; i < MAX_SERVER_KEYS; i++) {
+    if (server_keys[i].siv != NULL)
+      SIV_DestroyInstance(server_keys[i].siv);
+  }
+
+  for (i = 0; i < ARR_GetSize(sessions); i++) {
+    NKSN_Instance session = *(NKSN_Instance *)ARR_GetElement(sessions, i);
+    if (session)
+      NKSN_DestroyInstance(session);
+  }
+  ARR_DestroyInstance(sessions);
+
+  NKSN_DestroyCertCredentials(server_credentials);
+}
+
+/* ================================================== */
+
+void
+NKS_DumpKeys(void)
+{
+  save_keys();
+}
+
+/* ================================================== */
+
+void
+NKS_ReloadKeys(void)
+{
+  /* Don't load the keys if they are expected to be generated by this server
+     instance (i.e. they are already loaded) to not delay the next rotation */
+  if (key_rotation_interval > 0)
+    return;
+
+  load_keys();
+}
+
+/* ================================================== */
+
+/* A server cookie consists of key ID, nonce, and encrypted C2S+S2C keys */
+
+int
+NKS_GenerateCookie(NKE_Context *context, NKE_Cookie *cookie)
+{
+  unsigned char plaintext[2 * NKE_MAX_KEY_LENGTH], *ciphertext;
+  int plaintext_length, tag_length;
+  ServerCookieHeader *header;
+  ServerKey *key;
+
+  if (!initialised) {
+    DEBUG_LOG("NTS server disabled");
+    return 0;
+  }
+
+  /* The algorithm is hardcoded for now */
+  if (context->algorithm != AEAD_AES_SIV_CMAC_256) {
+    DEBUG_LOG("Unexpected SIV algorithm");
+    return 0;
+  }
+
+  if (context->c2s.length < 0 || context->c2s.length > NKE_MAX_KEY_LENGTH ||
+      context->s2c.length < 0 || context->s2c.length > NKE_MAX_KEY_LENGTH) {
+    DEBUG_LOG("Invalid key length");
+    return 0;
+  }
+
+  key = &server_keys[current_server_key];
+
+  header = (ServerCookieHeader *)cookie->cookie;
+
+  header->key_id = htonl(key->id);
+  UTI_GetRandomBytes(header->nonce, sizeof (header->nonce));
+
+  plaintext_length = context->c2s.length + context->s2c.length;
+  assert(plaintext_length <= sizeof (plaintext));
+  memcpy(plaintext, context->c2s.key, context->c2s.length);
+  memcpy(plaintext + context->c2s.length, context->s2c.key, context->s2c.length);
+
+  tag_length = SIV_GetTagLength(key->siv);
+  cookie->length = sizeof (*header) + plaintext_length + tag_length;
+  assert(cookie->length <= sizeof (cookie->cookie));
+  ciphertext = cookie->cookie + sizeof (*header);
+
+  if (!SIV_Encrypt(key->siv, header->nonce, sizeof (header->nonce),
+                   "", 0,
+                   plaintext, plaintext_length,
+                   ciphertext, plaintext_length + tag_length)) {
+    DEBUG_LOG("Could not encrypt cookie");
+    return 0;
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NKS_DecodeCookie(NKE_Cookie *cookie, NKE_Context *context)
+{
+  unsigned char plaintext[2 * NKE_MAX_KEY_LENGTH], *ciphertext;
+  int ciphertext_length, plaintext_length, tag_length;
+  ServerCookieHeader *header;
+  ServerKey *key;
+  uint32_t key_id;
+
+  if (!initialised) {
+    DEBUG_LOG("NTS server disabled");
+    return 0;
+  }
+
+  if (cookie->length <= sizeof (*header)) {
+    DEBUG_LOG("Invalid cookie length");
+    return 0;
+  }
+
+  header = (ServerCookieHeader *)cookie->cookie;
+  ciphertext = cookie->cookie + sizeof (*header);
+  ciphertext_length = cookie->length - sizeof (*header);
+
+  key_id = ntohl(header->key_id);
+  key = &server_keys[key_id % MAX_SERVER_KEYS];
+  if (key_id != key->id) {
+    DEBUG_LOG("Unknown key %"PRIX32, key_id);
+    return 0;
+  }
+
+  tag_length = SIV_GetTagLength(key->siv);
+  if (tag_length >= ciphertext_length) {
+    DEBUG_LOG("Invalid cookie length");
+    return 0;
+  }
+
+  plaintext_length = ciphertext_length - tag_length;
+  if (plaintext_length > sizeof (plaintext) || plaintext_length % 2 != 0) {
+    DEBUG_LOG("Invalid cookie length");
+    return 0;
+  }
+
+  if (!SIV_Decrypt(key->siv, header->nonce, sizeof (header->nonce),
+                   "", 0,
+                   ciphertext, ciphertext_length,
+                   plaintext, plaintext_length)) {
+    DEBUG_LOG("Could not decrypt cookie");
+    return 0;
+  }
+
+  context->algorithm = AEAD_AES_SIV_CMAC_256;
+
+  context->c2s.length = plaintext_length / 2;
+  context->s2c.length = plaintext_length / 2;
+  assert(context->c2s.length <= sizeof (context->c2s.key));
+
+  memcpy(context->c2s.key, plaintext, context->c2s.length);
+  memcpy(context->s2c.key, plaintext + context->c2s.length, context->s2c.length);
+
+  return 1;
+}

nts_ke_server.h

@@ -0,0 +1,48 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for the NTS-KE server
+  */
+
+#ifndef GOT_NTS_KE_SERVER_H
+#define GOT_NTS_KE_SERVER_H
+
+#include "nts_ke.h"
+
+/* Init and fini functions */
+extern void NKS_Initialise(int scfilter_level);
+extern void NKS_Finalise(void);
+
+/* Save the current server keys */
+extern void NKS_DumpKeys(void);
+
+/* Reload the keys */
+extern void NKS_ReloadKeys(void);
+
+/* Generate an NTS cookie with a given context */
+extern int NKS_GenerateCookie(NKE_Context *context, NKE_Cookie *cookie);
+
+/* Validate a cookie and decode the context */
+extern int NKS_DecodeCookie(NKE_Cookie *cookie, NKE_Context *context);
+
+#endif

nts_ke_session.c

@@ -0,0 +1,848 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  NTS-KE session used by server and client
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "nts_ke_session.h"
+
+#include "conf.h"
+#include "local.h"
+#include "logging.h"
+#include "memory.h"
+#include "siv.h"
+#include "socket.h"
+#include "sched.h"
+#include "util.h"
+
+#include <gnutls/gnutls.h>
+#include <gnutls/x509.h>
+
+#define INVALID_SOCK_FD (-8)
+
+struct RecordHeader {
+  uint16_t type;
+  uint16_t body_length;
+};
+
+struct Message {
+  int length;
+  int sent;
+  int parsed;
+  int complete;
+  unsigned char data[NKE_MAX_MESSAGE_LENGTH];
+};
+
+typedef enum {
+  KE_WAIT_CONNECT,
+  KE_HANDSHAKE,
+  KE_SEND,
+  KE_RECEIVE,
+  KE_SHUTDOWN,
+  KE_STOPPED,
+} KeState;
+
+struct NKSN_Instance_Record {
+  int server;
+  char *server_name;
+  NKSN_MessageHandler handler;
+  void *handler_arg;
+
+  KeState state;
+  int sock_fd;
+  char *label;
+  gnutls_session_t tls_session;
+  SCH_TimeoutID timeout_id;
+  int retry_factor;
+
+  struct Message message;
+  int new_message;
+  int ended_message;
+};
+
+/* ================================================== */
+
+static gnutls_priority_t priority_cache;
+
+static int credentials_counter = 0;
+
+static int clock_updates = 0;
+
+/* ================================================== */
+
+static void
+reset_message(struct Message *message)
+{
+  message->length = 0;
+  message->sent = 0;
+  message->parsed = 0;
+  message->complete = 0;
+}
+
+/* ================================================== */
+
+static int
+add_record(struct Message *message, int critical, int type, const void *body, int body_length)
+{
+  struct RecordHeader header;
+
+  if (body_length < 0 || body_length > 0xffff || type < 0 || type > 0x7fff ||
+      message->length + sizeof (header) + body_length > sizeof (message->data))
+    return 0;
+
+  header.type = htons(!!critical * NKE_RECORD_CRITICAL_BIT | type);
+  header.body_length = htons(body_length);
+
+  memcpy(&message->data[message->length], &header, sizeof (header));
+  message->length += sizeof (header);
+
+  if (body_length > 0) {
+    memcpy(&message->data[message->length], body, body_length);
+    message->length += body_length;
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+static void
+reset_message_parsing(struct Message *message)
+{
+  message->parsed = 0;
+}
+
+/* ================================================== */
+
+static int
+get_record(struct Message *message, int *critical, int *type, int *body_length,
+           void *body, int buffer_length)
+{
+  struct RecordHeader header;
+  int blen, rlen;
+
+  if (message->length < message->parsed + sizeof (header) ||
+      buffer_length < 0)
+    return 0;
+
+  memcpy(&header, &message->data[message->parsed], sizeof (header));
+
+  blen = ntohs(header.body_length);
+  rlen = sizeof (header) + blen;
+
+  if (message->length < message->parsed + rlen)
+    return 0;
+
+  if (critical)
+    *critical = !!(ntohs(header.type) & NKE_RECORD_CRITICAL_BIT);
+  if (type)
+    *type = ntohs(header.type) & ~NKE_RECORD_CRITICAL_BIT;
+  if (body)
+    memcpy(body, &message->data[message->parsed + sizeof (header)], MIN(buffer_length, blen));
+  if (body_length)
+    *body_length = blen;
+
+  message->parsed += rlen;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+check_message_format(struct Message *message, int eof)
+{
+  int critical = 0, type = -1, length = -1, ends = 0;
+
+  reset_message_parsing(message);
+  message->complete = 0;
+
+  while (get_record(message, &critical, &type, &length, NULL, 0)) {
+    if (type == NKE_RECORD_END_OF_MESSAGE) {
+      if (!critical || length != 0 || ends > 0)
+        return 0;
+      ends++;
+    }
+  }
+
+  /* If the message cannot be fully parsed, but more data may be coming,
+     consider the format to be ok */
+  if (message->length == 0 || message->parsed < message->length)
+    return !eof;
+
+  if (type != NKE_RECORD_END_OF_MESSAGE)
+    return !eof;
+
+  message->complete = 1;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static gnutls_session_t
+create_tls_session(int server_mode, int sock_fd, const char *server_name,
+                   gnutls_certificate_credentials_t credentials,
+                   gnutls_priority_t priority)
+{
+  unsigned char alpn_name[sizeof (NKE_ALPN_NAME)];
+  gnutls_session_t session;
+  gnutls_datum_t alpn;
+  unsigned int flags;
+  int r;
+
+  r = gnutls_init(&session, GNUTLS_NONBLOCK | (server_mode ? GNUTLS_SERVER : GNUTLS_CLIENT));
+  if (r < 0) {
+    LOG(LOGS_ERR, "Could not %s TLS session : %s", "create", gnutls_strerror(r));
+    return NULL;
+  }
+
+  if (!server_mode) {
+    r = gnutls_server_name_set(session, GNUTLS_NAME_DNS, server_name, strlen(server_name));
+    if (r < 0)
+      goto error;
+
+    flags = 0;
+
+    if (clock_updates < CNF_GetNoCertTimeCheck()) {
+      flags |= GNUTLS_VERIFY_DISABLE_TIME_CHECKS | GNUTLS_VERIFY_DISABLE_TRUSTED_TIME_CHECKS;
+      DEBUG_LOG("Disabled time checks");
+    }
+
+    gnutls_session_set_verify_cert(session, server_name, flags);
+  }
+
+  r = gnutls_priority_set(session, priority);
+  if (r < 0)
+    goto error;
+
+  r = gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, credentials);
+  if (r < 0)
+    goto error;
+
+  memcpy(alpn_name, NKE_ALPN_NAME, sizeof (alpn_name));
+  alpn.data = alpn_name;
+  alpn.size = sizeof (alpn_name) - 1;
+
+  r = gnutls_alpn_set_protocols(session, &alpn, 1, 0);
+  if (r < 0)
+    goto error;
+
+  gnutls_transport_set_int(session, sock_fd);
+
+  return session;
+
+error:
+  LOG(LOGS_ERR, "Could not %s TLS session : %s", "set", gnutls_strerror(r));
+  gnutls_deinit(session);
+  return NULL;
+}
+
+/* ================================================== */
+
+static void
+stop_session(NKSN_Instance inst)
+{
+  if (inst->state == KE_STOPPED)
+    return;
+
+  inst->state = KE_STOPPED;
+
+  SCH_RemoveFileHandler(inst->sock_fd);
+  SCK_CloseSocket(inst->sock_fd);
+  inst->sock_fd = INVALID_SOCK_FD;
+
+  Free(inst->label);
+  inst->label = NULL;
+
+  gnutls_deinit(inst->tls_session);
+  inst->tls_session = NULL;
+
+  SCH_RemoveTimeout(inst->timeout_id);
+  inst->timeout_id = 0;
+}
+
+/* ================================================== */
+
+static void
+session_timeout(void *arg)
+{
+  NKSN_Instance inst = arg;
+
+  LOG(inst->server ? LOGS_DEBUG : LOGS_ERR, "NTS-KE session with %s timed out", inst->label);
+
+  inst->timeout_id = 0;
+  stop_session(inst);
+}
+
+/* ================================================== */
+
+static int
+get_socket_error(int sock_fd)
+{
+  int optval;
+  socklen_t optlen = sizeof (optval);
+
+  if (getsockopt(sock_fd, SOL_SOCKET, SO_ERROR, &optval, &optlen) < 0) {
+    DEBUG_LOG("getsockopt() failed : %s", strerror(errno));
+    return EINVAL;
+  }
+
+  return optval;
+}
+
+/* ================================================== */
+
+static int
+check_alpn(NKSN_Instance inst)
+{
+  gnutls_datum_t alpn;
+  int r;
+
+  r = gnutls_alpn_get_selected_protocol(inst->tls_session, &alpn);
+  if (r < 0 || alpn.size != sizeof (NKE_ALPN_NAME) - 1 ||
+      strncmp((const char *)alpn.data, NKE_ALPN_NAME, sizeof (NKE_ALPN_NAME) - 1))
+    return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static void
+change_state(NKSN_Instance inst, KeState state)
+{
+  int output;
+
+  switch (state) {
+    case KE_HANDSHAKE:
+      output = !inst->server;
+      break;
+    case KE_WAIT_CONNECT:
+    case KE_SEND:
+    case KE_SHUTDOWN:
+      output = 1;
+      break;
+    case KE_RECEIVE:
+      output = 0;
+      break;
+    default:
+      assert(0);
+  }
+
+  SCH_SetFileHandlerEvent(inst->sock_fd, SCH_FILE_OUTPUT, output);
+
+  inst->state = state;
+}
+
+/* ================================================== */
+
+static int
+handle_event(NKSN_Instance inst, int event)
+{
+  struct Message *message = &inst->message;
+  int r;
+
+  DEBUG_LOG("Session event %d fd=%d state=%d", event, inst->sock_fd, (int)inst->state);
+
+  switch (inst->state) {
+    case KE_WAIT_CONNECT:
+      /* Check if connect() succeeded */
+      if (event != SCH_FILE_OUTPUT)
+        return 0;
+
+      r = get_socket_error(inst->sock_fd);
+
+      if (r) {
+        LOG(LOGS_ERR, "Could not connect to %s : %s", inst->label, strerror(r));
+        stop_session(inst);
+        return 0;
+      }
+
+      DEBUG_LOG("Connected to %s", inst->label);
+
+      change_state(inst, KE_HANDSHAKE);
+      return 0;
+
+    case KE_HANDSHAKE:
+      r = gnutls_handshake(inst->tls_session);
+
+      if (r < 0) {
+        if (gnutls_error_is_fatal(r)) {
+          LOG(inst->server ? LOGS_DEBUG : LOGS_ERR,
+              "TLS handshake with %s failed : %s", inst->label, gnutls_strerror(r));
+          stop_session(inst);
+
+          /* Increase the retry interval if the handshake did not fail due
+             to the other end closing the connection */
+          if (r != GNUTLS_E_PULL_ERROR && r != GNUTLS_E_PREMATURE_TERMINATION)
+            inst->retry_factor = NKE_RETRY_FACTOR2_TLS;
+
+          return 0;
+        }
+
+        /* Disable output when the handshake is trying to receive data */
+        SCH_SetFileHandlerEvent(inst->sock_fd, SCH_FILE_OUTPUT,
+                                gnutls_record_get_direction(inst->tls_session));
+        return 0;
+      }
+
+      inst->retry_factor = NKE_RETRY_FACTOR2_TLS;
+
+      if (DEBUG) {
+        char *description = gnutls_session_get_desc(inst->tls_session);
+        DEBUG_LOG("Handshake with %s completed %s",
+                  inst->label, description ? description : "");
+        gnutls_free(description);
+      }
+
+      if (!check_alpn(inst)) {
+        LOG(inst->server ? LOGS_DEBUG : LOGS_ERR, "NTS-KE not supported by %s", inst->label);
+        stop_session(inst);
+        return 0;
+      }
+
+      /* Client will send a request to the server */
+      change_state(inst, inst->server ? KE_RECEIVE : KE_SEND);
+      return 0;
+
+    case KE_SEND:
+      assert(inst->new_message && message->complete);
+
+      r = gnutls_record_send(inst->tls_session, &message->data[message->sent],
+                             message->length - message->sent);
+
+      if (r < 0) {
+        if (gnutls_error_is_fatal(r)) {
+          LOG(inst->server ? LOGS_DEBUG : LOGS_ERR,
+              "Could not send NTS-KE message to %s : %s", inst->label, gnutls_strerror(r));
+          stop_session(inst);
+        }
+        return 0;
+      }
+
+      DEBUG_LOG("Sent %d bytes to %s", r, inst->label);
+
+      message->sent += r;
+      if (message->sent < message->length)
+        return 0;
+
+      /* Client will receive a response */
+      change_state(inst, inst->server ? KE_SHUTDOWN : KE_RECEIVE);
+      reset_message(&inst->message);
+      inst->new_message = 0;
+      return 0;
+
+    case KE_RECEIVE:
+      do {
+        if (message->length >= sizeof (message->data)) {
+          DEBUG_LOG("Message is too long");
+          stop_session(inst);
+          return 0;
+        }
+
+        r = gnutls_record_recv(inst->tls_session, &message->data[message->length],
+                               sizeof (message->data) - message->length);
+
+        if (r < 0) {
+          /* Handle a renegotiation request on both client and server as
+             a protocol error */
+          if (gnutls_error_is_fatal(r) || r == GNUTLS_E_REHANDSHAKE) {
+            LOG(inst->server ? LOGS_DEBUG : LOGS_ERR,
+                "Could not receive NTS-KE message from %s : %s",
+                inst->label, gnutls_strerror(r));
+            stop_session(inst);
+          }
+          return 0;
+        }
+
+        DEBUG_LOG("Received %d bytes from %s", r, inst->label);
+
+        message->length += r;
+
+      } while (gnutls_record_check_pending(inst->tls_session) > 0);
+
+      if (!check_message_format(message, r == 0)) {
+        LOG(inst->server ? LOGS_DEBUG : LOGS_ERR,
+            "Received invalid NTS-KE message from %s", inst->label);
+        stop_session(inst);
+        return 0;
+      }
+
+      /* Wait for more data if the message is not complete yet */
+      if (!message->complete)
+        return 0;
+
+      /* Server will send a response to the client */
+      change_state(inst, inst->server ? KE_SEND : KE_SHUTDOWN);
+      break;
+
+    case KE_SHUTDOWN:
+      r = gnutls_bye(inst->tls_session, GNUTLS_SHUT_RDWR);
+
+      if (r < 0) {
+        if (gnutls_error_is_fatal(r)) {
+          DEBUG_LOG("Shutdown with %s failed : %s", inst->label, gnutls_strerror(r));
+          stop_session(inst);
+          return 0;
+        }
+
+        /* Disable output when the TLS shutdown is trying to receive data */
+        SCH_SetFileHandlerEvent(inst->sock_fd, SCH_FILE_OUTPUT,
+                                gnutls_record_get_direction(inst->tls_session));
+        return 0;
+      }
+
+      SCK_ShutdownConnection(inst->sock_fd);
+      stop_session(inst);
+
+      DEBUG_LOG("Shutdown completed");
+      return 0;
+
+    default:
+      assert(0);
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+static void
+read_write_socket(int fd, int event, void *arg)
+{
+  NKSN_Instance inst = arg;
+
+  if (!handle_event(inst, event))
+    return;
+
+  reset_message_parsing(&inst->message);
+
+  if (!(inst->handler)(inst->handler_arg)) {
+    stop_session(inst);
+    return;
+  }
+}
+
+/* ================================================== */
+
+static time_t
+get_time(time_t *t)
+{
+  struct timespec now;
+
+  LCL_ReadCookedTime(&now, NULL);
+  if (t)
+    *t = now.tv_sec;
+
+  return now.tv_sec;
+}
+
+/* ================================================== */
+
+static void
+handle_step(struct timespec *raw, struct timespec *cooked, double dfreq,
+            double doffset, LCL_ChangeType change_type, void *anything)
+{
+  if (change_type != LCL_ChangeUnknownStep && clock_updates < INT_MAX)
+    clock_updates++;
+}
+
+/* ================================================== */
+
+static int gnutls_initialised = 0;
+
+static void
+init_gnutls(void)
+{
+  int r;
+
+  if (gnutls_initialised)
+    return;
+
+  r = gnutls_global_init();
+  if (r < 0)
+    LOG_FATAL("Could not initialise %s : %s", "gnutls", gnutls_strerror(r));
+
+  /* NTS specification requires TLS1.3 or later */
+  r = gnutls_priority_init2(&priority_cache,
+                            "-VERS-SSL3.0:-VERS-TLS1.0:-VERS-TLS1.1:-VERS-TLS1.2",
+                            NULL, GNUTLS_PRIORITY_INIT_DEF_APPEND);
+  if (r < 0)
+    LOG_FATAL("Could not initialise %s : %s", "priority cache", gnutls_strerror(r));
+
+  gnutls_global_set_time_function(get_time);
+
+  gnutls_initialised = 1;
+
+  LCL_AddParameterChangeHandler(handle_step, NULL);
+}
+
+/* ================================================== */
+
+static void
+deinit_gnutls(void)
+{
+  assert(gnutls_initialised);
+
+  LCL_RemoveParameterChangeHandler(handle_step, NULL);
+
+  gnutls_priority_deinit(priority_cache);
+  gnutls_global_deinit();
+  gnutls_initialised = 0;
+}
+
+/* ================================================== */
+
+void *
+NKSN_CreateCertCredentials(char *cert, char *key, char *trusted_certs)
+{
+  gnutls_certificate_credentials_t credentials = NULL;
+  int r;
+
+  init_gnutls();
+
+  r = gnutls_certificate_allocate_credentials(&credentials);
+  if (r < 0)
+    goto error;
+
+  if (cert && key) {
+    r = gnutls_certificate_set_x509_key_file(credentials, cert, key,
+                                             GNUTLS_X509_FMT_PEM);
+    if (r < 0)
+      goto error;
+  } else {
+    if (!CNF_GetNoSystemCert()) {
+      r = gnutls_certificate_set_x509_system_trust(credentials);
+      if (r < 0)
+        goto error;
+    }
+
+    if (trusted_certs) {
+      r = gnutls_certificate_set_x509_trust_file(credentials, trusted_certs,
+                                                 GNUTLS_X509_FMT_PEM);
+      if (r < 0)
+        goto error;
+    }
+  }
+
+  credentials_counter++;
+
+  return credentials;
+
+error:
+  LOG(LOGS_ERR, "Could not set credentials : %s", gnutls_strerror(r));
+  if (credentials)
+    gnutls_certificate_free_credentials(credentials);
+  return NULL;
+}
+
+/* ================================================== */
+
+void
+NKSN_DestroyCertCredentials(void *credentials)
+{
+  gnutls_certificate_free_credentials(credentials);
+  credentials_counter--;
+  if (credentials_counter != 0)
+    return;
+
+  deinit_gnutls();
+}
+
+/* ================================================== */
+
+NKSN_Instance
+NKSN_CreateInstance(int server_mode, const char *server_name,
+                    NKSN_MessageHandler handler, void *handler_arg)
+{
+  NKSN_Instance inst;
+
+  inst = MallocNew(struct NKSN_Instance_Record);
+
+  inst->server = server_mode;
+  inst->server_name = server_name ? Strdup(server_name) : NULL;
+  inst->handler = handler;
+  inst->handler_arg = handler_arg;
+  /* Replace NULL arg with the session itself */
+  if (!inst->handler_arg)
+    inst->handler_arg = inst;
+
+  inst->state = KE_STOPPED;
+  inst->sock_fd = INVALID_SOCK_FD;
+  inst->label = NULL;
+  inst->tls_session = NULL;
+  inst->timeout_id = 0;
+  inst->retry_factor = NKE_RETRY_FACTOR2_CONNECT;
+
+  return inst;
+}
+
+/* ================================================== */
+
+void
+NKSN_DestroyInstance(NKSN_Instance inst)
+{
+  stop_session(inst);
+
+  Free(inst->server_name);
+  Free(inst);
+}
+
+/* ================================================== */
+
+int
+NKSN_StartSession(NKSN_Instance inst, int sock_fd, const char *label,
+                  void *credentials, double timeout)
+{
+  assert(inst->state == KE_STOPPED);
+
+  inst->tls_session = create_tls_session(inst->server, sock_fd, inst->server_name,
+                                         credentials, priority_cache);
+  if (!inst->tls_session)
+    return 0;
+
+  inst->sock_fd = sock_fd;
+  SCH_AddFileHandler(sock_fd, SCH_FILE_INPUT, read_write_socket, inst);
+
+  inst->label = Strdup(label);
+  inst->timeout_id = SCH_AddTimeoutByDelay(timeout, session_timeout, inst);
+  inst->retry_factor = NKE_RETRY_FACTOR2_CONNECT;
+
+  reset_message(&inst->message);
+  inst->new_message = 0;
+  inst->ended_message = 0;
+
+  change_state(inst, inst->server ? KE_HANDSHAKE : KE_WAIT_CONNECT);
+
+  return 1;
+}
+
+/* ================================================== */
+
+void
+NKSN_BeginMessage(NKSN_Instance inst)
+{
+  reset_message(&inst->message);
+  inst->new_message = 1;
+}
+
+/* ================================================== */
+
+int
+NKSN_AddRecord(NKSN_Instance inst, int critical, int type, const void *body, int body_length)
+{
+  assert(inst->new_message && !inst->message.complete);
+  assert(type != NKE_RECORD_END_OF_MESSAGE);
+
+  return add_record(&inst->message, critical, type, body, body_length);
+}
+
+/* ================================================== */
+
+int
+NKSN_EndMessage(NKSN_Instance inst)
+{
+  assert(!inst->message.complete);
+
+  if (!add_record(&inst->message, 1, NKE_RECORD_END_OF_MESSAGE, NULL, 0))
+    return 0;
+
+  inst->message.complete = 1;
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NKSN_GetRecord(NKSN_Instance inst, int *critical, int *type, int *body_length,
+               void *body, int buffer_length)
+{
+  int type2;
+
+  assert(inst->message.complete);
+
+  if (!get_record(&inst->message, critical, &type2, body_length, body, buffer_length))
+    return 0;
+
+  if (type2 == NKE_RECORD_END_OF_MESSAGE)
+    return 0;
+
+  if (type)
+    *type = type2;
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NKSN_GetKeys(NKSN_Instance inst, SIV_Algorithm siv, NKE_Key *c2s, NKE_Key *s2c)
+{
+  c2s->length = SIV_GetKeyLength(siv);
+  s2c->length = SIV_GetKeyLength(siv);
+  assert(c2s->length <= sizeof (c2s->key));
+  assert(s2c->length <= sizeof (s2c->key));
+
+  if (gnutls_prf_rfc5705(inst->tls_session,
+                         sizeof (NKE_EXPORTER_LABEL) - 1, NKE_EXPORTER_LABEL,
+                         sizeof (NKE_EXPORTER_CONTEXT_C2S) - 1, NKE_EXPORTER_CONTEXT_C2S,
+                         c2s->length, (char *)c2s->key) < 0)
+    return 0;
+  if (gnutls_prf_rfc5705(inst->tls_session,
+                         sizeof (NKE_EXPORTER_LABEL) - 1, NKE_EXPORTER_LABEL,
+                         sizeof (NKE_EXPORTER_CONTEXT_S2C) - 1, NKE_EXPORTER_CONTEXT_S2C,
+                         s2c->length, (char *)s2c->key) < 0)
+    return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NKSN_IsStopped(NKSN_Instance inst)
+{
+  return inst->state == KE_STOPPED;
+}
+
+/* ================================================== */
+
+void
+NKSN_StopSession(NKSN_Instance inst)
+{
+  stop_session(inst);
+}
+
+/* ================================================== */
+
+int
+NKSN_GetRetryFactor(NKSN_Instance inst)
+{
+  return inst->retry_factor;
+}

nts_ke_session.h

@@ -0,0 +1,87 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for the NTS-KE session
+  */
+
+#ifndef GOT_NTS_KE_SESSION_H
+#define GOT_NTS_KE_SESSION_H
+
+#include "nts_ke.h"
+#include "siv.h"
+
+typedef struct NKSN_Instance_Record *NKSN_Instance;
+
+/* Handler for received NTS-KE messages.  A non-zero return code stops
+   the session. */
+typedef int (*NKSN_MessageHandler)(void *arg);
+
+/* Get client or server credentials using certificates of trusted CAs,
+   or a server certificate and key.  The credentials may be shared between
+   different clients or servers. */
+extern void *NKSN_CreateCertCredentials(char *cert, char *key, char *trusted_certs);
+
+/* Destroy the credentials */
+extern void NKSN_DestroyCertCredentials(void *credentials);
+
+/* Create an instance */
+extern NKSN_Instance NKSN_CreateInstance(int server_mode, const char *server_name,
+                                         NKSN_MessageHandler handler, void *handler_arg);
+
+/* Destroy an instance */
+extern void NKSN_DestroyInstance(NKSN_Instance inst);
+
+/* Start a new NTS-KE session */
+extern int NKSN_StartSession(NKSN_Instance inst, int sock_fd, const char *label,
+                             void *credentials, double timeout);
+
+/* Begin an NTS-KE message.  A request should be made right after starting
+   the session and response should be made in the message handler. */
+extern void NKSN_BeginMessage(NKSN_Instance inst);
+
+/* Add a record to the message */
+extern int NKSN_AddRecord(NKSN_Instance inst, int critical, int type,
+                          const void *body, int body_length);
+
+/* Terminate the message */
+extern int NKSN_EndMessage(NKSN_Instance inst);
+
+/* Get the next record from the received message.  This function should be
+   called from the message handler. */
+extern int NKSN_GetRecord(NKSN_Instance inst, int *critical, int *type, int *body_length,
+                          void *body, int buffer_length);
+
+/* Export NTS keys for a specified algorithm */
+extern int NKSN_GetKeys(NKSN_Instance inst, SIV_Algorithm siv, NKE_Key *c2s, NKE_Key *s2c);
+
+/* Check if the session has stopped */
+extern int NKSN_IsStopped(NKSN_Instance inst);
+
+/* Stop the session */
+extern void NKSN_StopSession(NKSN_Instance inst);
+
+/* Get a factor to calculate retry interval (in log2 seconds)
+   based on the session state or how it was terminated */
+extern int NKSN_GetRetryFactor(NKSN_Instance inst);
+
+#endif

nts_ntp.h

@@ -0,0 +1,41 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for the NTS-NTP protocol
+  */
+
+#ifndef GOT_NTS_NTP_H
+#define GOT_NTS_NTP_H
+
+#define NTP_EF_NTS_UNIQUE_IDENTIFIER    0x0104
+#define NTP_EF_NTS_COOKIE               0x0204
+#define NTP_EF_NTS_COOKIE_PLACEHOLDER   0x0304
+#define NTP_EF_NTS_AUTH_AND_EEF         0x0404
+
+#define NTP_KOD_NTS_NAK                 0x4e54534e
+
+#define NTS_MIN_UNIQ_ID_LENGTH          32
+#define NTS_MIN_UNPADDED_NONCE_LENGTH   16
+#define NTS_MAX_COOKIES                 8
+
+#endif

nts_ntp_auth.c

@@ -0,0 +1,174 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  NTS Authenticator and Encrypted Extension Fields extension field
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "nts_ntp_auth.h"
+
+#include "logging.h"
+#include "ntp_ext.h"
+#include "nts_ntp.h"
+#include "siv.h"
+#include "util.h"
+
+struct AuthHeader {
+  uint16_t nonce_length;
+  uint16_t ciphertext_length;
+};
+
+/* ================================================== */
+
+static int
+get_padding_length(int length)
+{
+  return length % 4U ? 4 - length % 4U : 0;
+}
+
+/* ================================================== */
+
+static int
+get_padded_length(int length)
+{
+  return length + get_padding_length(length);
+}
+
+/* ================================================== */
+
+int
+NNA_GenerateAuthEF(NTP_Packet *packet, NTP_PacketInfo *info, SIV_Instance siv,
+                   const unsigned char *nonce, int nonce_length,
+                   const unsigned char *plaintext, int plaintext_length,
+                   int min_ef_length)
+{
+  int auth_length, ciphertext_length, assoc_length;
+  int nonce_padding, ciphertext_padding, additional_padding;
+  unsigned char *ciphertext, *body;
+  struct AuthHeader *header;
+
+  assert(sizeof (*header) == 4);
+
+  if (nonce_length <= 0 || plaintext_length < 0) {
+    DEBUG_LOG("Invalid nonce/plaintext length");
+    return 0;
+  }
+
+  assoc_length = info->length;
+  ciphertext_length = SIV_GetTagLength(siv) + plaintext_length;
+  nonce_padding = get_padding_length(nonce_length);
+  ciphertext_padding = get_padding_length(ciphertext_length);
+  min_ef_length = get_padded_length(min_ef_length);
+
+  auth_length = sizeof (*header) + nonce_length + nonce_padding +
+                ciphertext_length + ciphertext_padding;
+  additional_padding = MAX(min_ef_length - auth_length - 4, 0);
+  additional_padding = MAX(NTS_MIN_UNPADDED_NONCE_LENGTH - nonce_length - nonce_padding,
+                           additional_padding);
+  auth_length += additional_padding;
+
+  if (!NEF_AddBlankField(packet, info, NTP_EF_NTS_AUTH_AND_EEF, auth_length,
+                         (void **)&header)) {
+    DEBUG_LOG("Could not add EF");
+    return 0;
+  }
+
+  header->nonce_length = htons(nonce_length);
+  header->ciphertext_length = htons(ciphertext_length);
+
+  body = (unsigned char *)(header + 1);
+  ciphertext = body + nonce_length + nonce_padding;
+
+  memcpy(body, nonce, nonce_length);
+  memset(body + nonce_length, 0, nonce_padding);
+
+  if (!SIV_Encrypt(siv, nonce, nonce_length, packet, assoc_length,
+                   plaintext, plaintext_length, ciphertext, ciphertext_length)) {
+    DEBUG_LOG("SIV encrypt failed");
+    return 0;
+  }
+
+  memset(ciphertext + ciphertext_length, 0, ciphertext_padding + additional_padding);
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NNA_DecryptAuthEF(NTP_Packet *packet, NTP_PacketInfo *info, SIV_Instance siv, int ef_start,
+                  unsigned char *plaintext, int buffer_length, int *plaintext_length)
+{
+  unsigned int siv_tag_length, nonce_length, ciphertext_length;
+  unsigned char *nonce, *ciphertext;
+  int ef_type, ef_body_length;
+  void *ef_body;
+  struct AuthHeader *header;
+
+  if (!NEF_ParseField(packet, info->length, ef_start,
+                      NULL, &ef_type, &ef_body, &ef_body_length))
+    return 0;
+
+  if (ef_type != NTP_EF_NTS_AUTH_AND_EEF)
+    return 0;
+
+  header = ef_body;
+
+  nonce_length = ntohs(header->nonce_length);
+  ciphertext_length = ntohs(header->ciphertext_length);
+
+  if (get_padded_length(nonce_length) +
+      get_padded_length(ciphertext_length) > ef_body_length)
+    return 0;
+
+  nonce = (unsigned char *)(header + 1);
+  ciphertext = (unsigned char *)(header + 1) + get_padded_length(nonce_length);
+
+  siv_tag_length = SIV_GetTagLength(siv);
+
+  if (nonce_length < 1 ||
+      ciphertext_length < siv_tag_length ||
+      ciphertext_length - siv_tag_length > buffer_length) {
+    DEBUG_LOG("Unexpected nonce/ciphertext length");
+    return 0;
+  }
+
+  if (ef_body_length < sizeof (*header) +
+        NTS_MIN_UNPADDED_NONCE_LENGTH + get_padded_length(ciphertext_length)) {
+    DEBUG_LOG("Missing padding");
+    return 0;
+  }
+
+  *plaintext_length = ciphertext_length - siv_tag_length;
+
+  if (!SIV_Decrypt(siv, nonce, nonce_length, packet, info->length - ef_body_length - 4,
+                   ciphertext, ciphertext_length, plaintext, *plaintext_length)) {
+    DEBUG_LOG("SIV decrypt failed");
+    return 0;
+  }
+
+  return 1;
+}

nts_ntp_auth.h

@@ -0,0 +1,43 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header for NTS Authenticator and Encrypted Extension Fields
+  extension field
+  */
+
+#ifndef GOT_NTS_NTP_AUTH_H
+#define GOT_NTS_NTP_AUTH_H
+
+#include "ntp.h"
+#include "siv.h"
+
+extern int NNA_GenerateAuthEF(NTP_Packet *packet, NTP_PacketInfo *info, SIV_Instance siv,
+                              const unsigned char *nonce, int nonce_length,
+                              const unsigned char *plaintext, int plaintext_length,
+                              int min_ef_length);
+
+extern int NNA_DecryptAuthEF(NTP_Packet *packet, NTP_PacketInfo *info, SIV_Instance siv,
+                             int ef_start, unsigned char *plaintext, int buffer_length,
+                             int *plaintext_length);
+
+#endif

nts_ntp_client.c

@@ -0,0 +1,629 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Client NTS-NTP authentication
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "nts_ntp_client.h"
+
+#include "conf.h"
+#include "logging.h"
+#include "memory.h"
+#include "ntp.h"
+#include "ntp_ext.h"
+#include "ntp_sources.h"
+#include "nts_ke_client.h"
+#include "nts_ntp.h"
+#include "nts_ntp_auth.h"
+#include "sched.h"
+#include "siv.h"
+#include "util.h"
+
+#define MAX_TOTAL_COOKIE_LENGTH (8 * 108)
+
+#define DUMP_IDENTIFIER "NNC0\n"
+
+struct NNC_Instance_Record {
+  const IPSockAddr *ntp_address;
+  IPSockAddr nts_address;
+  char *name;
+  NKC_Instance nke;
+  SIV_Instance siv;
+
+  int load_attempt;
+  int nke_attempts;
+  double next_nke_attempt;
+  double last_nke_success;
+
+  NKE_Context context;
+  NKE_Cookie cookies[NTS_MAX_COOKIES];
+  int num_cookies;
+  int cookie_index;
+  int nak_response;
+  int ok_response;
+  unsigned char nonce[NTS_MIN_UNPADDED_NONCE_LENGTH];
+  unsigned char uniq_id[NTS_MIN_UNIQ_ID_LENGTH];
+};
+
+/* ================================================== */
+
+static void save_cookies(NNC_Instance inst);
+static void load_cookies(NNC_Instance inst);
+
+/* ================================================== */
+
+static void
+reset_instance(NNC_Instance inst)
+{
+  inst->load_attempt = 0;
+  inst->nke_attempts = 0;
+  inst->next_nke_attempt = 0.0;
+  inst->last_nke_success = 0.0;
+
+  memset(&inst->context, 0, sizeof (inst->context));
+  inst->num_cookies = 0;
+  inst->cookie_index = 0;
+  inst->nak_response = 0;
+  inst->ok_response = 1;
+  memset(inst->nonce, 0, sizeof (inst->nonce));
+  memset(inst->uniq_id, 0, sizeof (inst->uniq_id));
+}
+
+/* ================================================== */
+
+NNC_Instance
+NNC_CreateInstance(IPSockAddr *nts_address, const char *name, const IPSockAddr *ntp_address)
+{
+  NNC_Instance inst;
+
+  inst = MallocNew(struct NNC_Instance_Record);
+
+  inst->ntp_address = ntp_address;
+  inst->nts_address = *nts_address;
+  inst->name = name ? Strdup(name) : NULL;
+  inst->siv = NULL;
+  inst->nke = NULL;
+
+  reset_instance(inst);
+
+  return inst;
+}
+
+/* ================================================== */
+
+void
+NNC_DestroyInstance(NNC_Instance inst)
+{
+  save_cookies(inst);
+
+  if (inst->nke)
+    NKC_DestroyInstance(inst->nke);
+  if (inst->siv)
+    SIV_DestroyInstance(inst->siv);
+
+  Free(inst->name);
+  Free(inst);
+}
+
+/* ================================================== */
+
+static int
+check_cookies(NNC_Instance inst)
+{
+  /* Force NKE if a NAK was received since last valid auth */
+  if (inst->nak_response && !inst->ok_response && inst->num_cookies > 0) {
+    inst->num_cookies = 0;
+    DEBUG_LOG("Dropped cookies");
+  }
+
+  /* Force NKE if the keys encrypting the cookies are too old */
+  if (inst->num_cookies > 0 &&
+      SCH_GetLastEventMonoTime() - inst->last_nke_success > CNF_GetNtsRefresh())
+    inst->num_cookies = 0;
+
+  return inst->num_cookies > 0;
+}
+
+/* ================================================== */
+
+static int
+set_ntp_address(NNC_Instance inst, NTP_Remote_Address *negotiated_address)
+{
+  NTP_Remote_Address old_address, new_address;
+
+  old_address = *inst->ntp_address;
+  new_address = *negotiated_address;
+
+  if (new_address.ip_addr.family == IPADDR_UNSPEC)
+    new_address.ip_addr = old_address.ip_addr;
+  if (new_address.port == 0)
+    new_address.port = old_address.port;
+
+  if (UTI_CompareIPs(&old_address.ip_addr, &new_address.ip_addr, NULL) == 0 &&
+      old_address.port == new_address.port)
+    /* Nothing to do */
+    return 1;
+
+  if (NSR_UpdateSourceNtpAddress(&old_address, &new_address) != NSR_Success) {
+    LOG(LOGS_ERR, "Could not change %s to negotiated address %s",
+        UTI_IPToString(&old_address.ip_addr), UTI_IPToString(&new_address.ip_addr));
+    return 0;
+  }
+
+  return 1;
+}
+
+/* ================================================== */
+
+static void
+update_next_nke_attempt(NNC_Instance inst, double now)
+{
+  int factor, interval;
+
+  if (!inst->nke)
+    return;
+
+  factor = NKC_GetRetryFactor(inst->nke);
+  interval = MIN(factor + inst->nke_attempts - 1, NKE_MAX_RETRY_INTERVAL2);
+  inst->next_nke_attempt = now + UTI_Log2ToDouble(interval);
+}
+
+/* ================================================== */
+
+static int
+get_cookies(NNC_Instance inst)
+{
+  NTP_Remote_Address ntp_address;
+  double now;
+  int got_data;
+
+  assert(!check_cookies(inst));
+
+  now = SCH_GetLastEventMonoTime();
+
+  if (!inst->nke) {
+    if (now < inst->next_nke_attempt) {
+      DEBUG_LOG("Limiting NTS-KE request rate (%f seconds)",
+                inst->next_nke_attempt - now);
+      return 0;
+    }
+
+    if (!inst->name) {
+      LOG(LOGS_ERR, "Missing name of %s for NTS-KE",
+          UTI_IPToString(&inst->nts_address.ip_addr));
+      return 0;
+    }
+
+    inst->nke = NKC_CreateInstance(&inst->nts_address, inst->name);
+
+    inst->nke_attempts++;
+    update_next_nke_attempt(inst, now);
+
+    if (!NKC_Start(inst->nke))
+      return 0;
+  }
+
+  update_next_nke_attempt(inst, now);
+
+  if (NKC_IsActive(inst->nke))
+    return 0;
+
+  got_data = NKC_GetNtsData(inst->nke, &inst->context,
+                            inst->cookies, &inst->num_cookies, NTS_MAX_COOKIES,
+                            &ntp_address);
+
+  NKC_DestroyInstance(inst->nke);
+  inst->nke = NULL;
+
+  if (!got_data)
+    return 0;
+
+  if (inst->siv)
+    SIV_DestroyInstance(inst->siv);
+  inst->siv = NULL;
+
+  if (!set_ntp_address(inst, &ntp_address)) {
+    inst->num_cookies = 0;
+    return 0;
+  }
+
+  inst->cookie_index = 0;
+
+  inst->nak_response = 0;
+
+  inst->last_nke_success = now;
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NNC_PrepareForAuth(NNC_Instance inst)
+{
+  if (!inst->load_attempt) {
+    load_cookies(inst);
+    inst->load_attempt = 1;
+  }
+
+  if (!check_cookies(inst)) {
+    if (!get_cookies(inst))
+      return 0;
+  }
+
+  if (!inst->siv)
+    inst->siv = SIV_CreateInstance(inst->context.algorithm);
+
+  if (!inst->siv ||
+      !SIV_SetKey(inst->siv, inst->context.c2s.key, inst->context.c2s.length)) {
+    DEBUG_LOG("Could not set SIV key");
+    return 0;
+  }
+
+  UTI_GetRandomBytes(&inst->uniq_id, sizeof (inst->uniq_id));
+  UTI_GetRandomBytes(&inst->nonce, sizeof (inst->nonce));
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NNC_GenerateRequestAuth(NNC_Instance inst, NTP_Packet *packet,
+                        NTP_PacketInfo *info)
+{
+  NKE_Cookie *cookie;
+  int i, req_cookies;
+  void *ef_body;
+
+  if (inst->num_cookies == 0 || !inst->siv)
+    return 0;
+
+  if (info->mode != MODE_CLIENT)
+    return 0;
+
+  cookie = &inst->cookies[inst->cookie_index];
+  req_cookies = MIN(NTS_MAX_COOKIES - inst->num_cookies + 1,
+                    MAX_TOTAL_COOKIE_LENGTH / (cookie->length + 4));
+
+  if (!NEF_AddField(packet, info, NTP_EF_NTS_UNIQUE_IDENTIFIER,
+                    &inst->uniq_id, sizeof (inst->uniq_id)))
+    return 0;
+
+  if (!NEF_AddField(packet, info, NTP_EF_NTS_COOKIE,
+                    cookie->cookie, cookie->length))
+    return 0;
+
+  for (i = 0; i < req_cookies - 1; i++) {
+    if (!NEF_AddBlankField(packet, info, NTP_EF_NTS_COOKIE_PLACEHOLDER,
+                           cookie->length, &ef_body))
+      return 0;
+    memset(ef_body, 0, cookie->length);
+  }
+
+  if (!NNA_GenerateAuthEF(packet, info, inst->siv, inst->nonce, sizeof (inst->nonce),
+                          (const unsigned char *)"", 0, NTP_MAX_V4_MAC_LENGTH + 4))
+    return 0;
+
+  inst->num_cookies--;
+  inst->cookie_index = (inst->cookie_index + 1) % NTS_MAX_COOKIES;
+  inst->ok_response = 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+extract_cookies(NNC_Instance inst, unsigned char *plaintext, int length)
+{
+  int ef_type, ef_body_length, ef_length, parsed, index, acceptable, saved;
+  void *ef_body;
+
+  acceptable = saved = 0;
+
+  for (parsed = 0; parsed < length; parsed += ef_length) {
+    if (!NEF_ParseSingleField(plaintext, length, parsed,
+                              &ef_length, &ef_type, &ef_body, &ef_body_length))
+      break;
+
+    if (ef_type != NTP_EF_NTS_COOKIE)
+      continue;
+
+    if (ef_length < NTP_MIN_EF_LENGTH || ef_body_length > sizeof (inst->cookies[0].cookie)) {
+      DEBUG_LOG("Unexpected cookie length %d", ef_body_length);
+      continue;
+    }
+
+    acceptable++;
+
+    if (inst->num_cookies >= NTS_MAX_COOKIES)
+      continue;
+
+    index = (inst->cookie_index + inst->num_cookies) % NTS_MAX_COOKIES;
+    memcpy(inst->cookies[index].cookie, ef_body, ef_body_length);
+    inst->cookies[index].length = ef_body_length;
+    inst->num_cookies++;
+
+    saved++;
+  }
+
+  DEBUG_LOG("Extracted %d cookies (saved %d)", acceptable, saved);
+
+  return acceptable > 0;
+}
+
+/* ================================================== */
+
+int
+NNC_CheckResponseAuth(NNC_Instance inst, NTP_Packet *packet,
+                      NTP_PacketInfo *info)
+{
+  int ef_type, ef_body_length, ef_length, parsed, plaintext_length;
+  int has_valid_uniq_id = 0, has_valid_auth = 0;
+  unsigned char plaintext[NTP_MAX_EXTENSIONS_LENGTH];
+  void *ef_body;
+
+  if (info->ext_fields == 0 || info->mode != MODE_SERVER)
+    return 0;
+
+  /* Accept only one response per request */
+  if (inst->ok_response)
+    return 0;
+
+  if (!inst->siv ||
+      !SIV_SetKey(inst->siv, inst->context.s2c.key, inst->context.s2c.length)) {
+    DEBUG_LOG("Could not set SIV key");
+    return 0;
+  }
+
+  for (parsed = NTP_HEADER_LENGTH; parsed < info->length; parsed += ef_length) {
+    if (!NEF_ParseField(packet, info->length, parsed,
+                        &ef_length, &ef_type, &ef_body, &ef_body_length))
+      break;
+
+    switch (ef_type) {
+      case NTP_EF_NTS_UNIQUE_IDENTIFIER:
+        if (ef_body_length != sizeof (inst->uniq_id) ||
+            memcmp(ef_body, inst->uniq_id, sizeof (inst->uniq_id)) != 0) {
+          DEBUG_LOG("Invalid uniq id");
+          return 0;
+        }
+        has_valid_uniq_id = 1;
+        break;
+      case NTP_EF_NTS_COOKIE:
+        DEBUG_LOG("Unencrypted cookie");
+        break;
+      case NTP_EF_NTS_AUTH_AND_EEF:
+        if (parsed + ef_length != info->length) {
+          DEBUG_LOG("Auth not last EF");
+          return 0;
+        }
+
+        if (!NNA_DecryptAuthEF(packet, info, inst->siv, parsed,
+                               plaintext, sizeof (plaintext), &plaintext_length))
+          return 0;
+
+        has_valid_auth = 1;
+        break;
+      default:
+        break;
+    }
+  }
+
+  if (!has_valid_uniq_id || !has_valid_auth) {
+    if (has_valid_uniq_id && packet->stratum == NTP_INVALID_STRATUM &&
+        ntohl(packet->reference_id) == NTP_KOD_NTS_NAK) {
+      DEBUG_LOG("NTS NAK");
+      inst->nak_response = 1;
+      return 0;
+    }
+
+    DEBUG_LOG("Missing NTS EF");
+    return 0;
+  }
+
+  if (!extract_cookies(inst, plaintext, plaintext_length))
+    return 0;
+
+  inst->ok_response = 1;
+
+  /* At this point we know the client interoperates with the server.  Allow a
+     new NTS-KE session to be started as soon as the cookies run out. */
+  inst->nke_attempts = 0;
+  inst->next_nke_attempt = 0.0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+void
+NNC_ChangeAddress(NNC_Instance inst, IPAddr *address)
+{
+  save_cookies(inst);
+
+  if (inst->nke)
+    NKC_DestroyInstance(inst->nke);
+
+  inst->nke = NULL;
+  inst->num_cookies = 0;
+  inst->nts_address.ip_addr = *address;
+
+  reset_instance(inst);
+
+  DEBUG_LOG("NTS reset");
+}
+
+/* ================================================== */
+
+static void
+save_cookies(NNC_Instance inst)
+{
+  char buf[2 * NKE_MAX_COOKIE_LENGTH + 2], *dump_dir, *filename;
+  struct timespec now;
+  double context_time;
+  FILE *f;
+  int i;
+
+  if (inst->num_cookies < 1 || !UTI_IsIPReal(&inst->nts_address.ip_addr))
+    return;
+
+  dump_dir = CNF_GetNtsDumpDir();
+  if (!dump_dir)
+    return;
+
+  filename = UTI_IPToString(&inst->nts_address.ip_addr);
+
+  f = UTI_OpenFile(dump_dir, filename, ".tmp", 'w', 0600);
+  if (!f)
+    return;
+
+  SCH_GetLastEventTime(&now, NULL, NULL);
+  context_time = inst->last_nke_success - SCH_GetLastEventMonoTime();
+  context_time += UTI_TimespecToDouble(&now);
+
+  if (fprintf(f, "%s%.1f\n%s %d\n%d ",
+              DUMP_IDENTIFIER, context_time, UTI_IPToString(&inst->ntp_address->ip_addr),
+              inst->ntp_address->port, (int)inst->context.algorithm) < 0 ||
+      !UTI_BytesToHex(inst->context.s2c.key, inst->context.s2c.length, buf, sizeof (buf)) ||
+      fprintf(f, "%s ", buf) < 0 ||
+      !UTI_BytesToHex(inst->context.c2s.key, inst->context.c2s.length, buf, sizeof (buf)) ||
+      fprintf(f, "%s\n", buf) < 0)
+    goto error;
+
+  for (i = 0; i < inst->num_cookies; i++) {
+    if (!UTI_BytesToHex(inst->cookies[i].cookie, inst->cookies[i].length, buf, sizeof (buf)) ||
+        fprintf(f, "%s\n", buf) < 0)
+      goto error;
+  }
+
+  fclose(f);
+
+  if (!UTI_RenameTempFile(dump_dir, filename, ".tmp", ".nts"))
+    ;
+  return;
+
+error:
+  DEBUG_LOG("Could not %s cookies for %s", "save", filename);
+  fclose(f);
+
+  if (!UTI_RemoveFile(dump_dir, filename, ".nts"))
+    ;
+}
+
+/* ================================================== */
+
+#define MAX_WORDS 3
+
+static void
+load_cookies(NNC_Instance inst)
+{
+  char line[2 * NKE_MAX_COOKIE_LENGTH + 2], *dump_dir, *filename, *words[MAX_WORDS];
+  int i, algorithm, port;
+  double context_time;
+  struct timespec now;
+  IPSockAddr ntp_addr;
+  FILE *f;
+
+  dump_dir = CNF_GetNtsDumpDir();
+  if (!dump_dir)
+    return;
+
+  filename = UTI_IPToString(&inst->nts_address.ip_addr);
+
+  f = UTI_OpenFile(dump_dir, filename, ".nts", 'r', 0);
+  if (!f)
+    return;
+
+  /* Don't load this file again */
+  if (!UTI_RemoveFile(dump_dir, filename, ".nts"))
+    ;
+
+  if (inst->siv)
+    SIV_DestroyInstance(inst->siv);
+  inst->siv = NULL;
+
+  if (!fgets(line, sizeof (line), f) || strcmp(line, DUMP_IDENTIFIER) != 0 ||
+      !fgets(line, sizeof (line), f) || UTI_SplitString(line, words, MAX_WORDS) != 1 ||
+        sscanf(words[0], "%lf", &context_time) != 1 ||
+      !fgets(line, sizeof (line), f) || UTI_SplitString(line, words, MAX_WORDS) != 2 ||
+        !UTI_StringToIP(words[0], &ntp_addr.ip_addr) || sscanf(words[1], "%d", &port) != 1 ||
+      !fgets(line, sizeof (line), f) || UTI_SplitString(line, words, MAX_WORDS) != 3 ||
+        sscanf(words[0], "%d", &algorithm) != 1)
+    goto error;
+
+  inst->context.algorithm = algorithm;
+  inst->context.s2c.length = UTI_HexToBytes(words[1], inst->context.s2c.key,
+                                            sizeof (inst->context.s2c.key));
+  inst->context.c2s.length = UTI_HexToBytes(words[2], inst->context.c2s.key,
+                                            sizeof (inst->context.c2s.key));
+
+  if (inst->context.s2c.length != SIV_GetKeyLength(algorithm) ||
+      inst->context.c2s.length != inst->context.s2c.length)
+    goto error;
+
+  for (i = 0; i < NTS_MAX_COOKIES && fgets(line, sizeof (line), f); i++) {
+    if (UTI_SplitString(line, words, MAX_WORDS) != 1)
+      goto error;
+
+    inst->cookies[i].length = UTI_HexToBytes(words[0], inst->cookies[i].cookie,
+                                             sizeof (inst->cookies[i].cookie));
+    if (inst->cookies[i].length == 0)
+      goto error;
+  }
+
+  inst->num_cookies = i;
+
+  ntp_addr.port = port;
+  if (!set_ntp_address(inst, &ntp_addr))
+    goto error;
+
+  SCH_GetLastEventTime(&now, NULL, NULL);
+  context_time -= UTI_TimespecToDouble(&now);
+  if (context_time > 0)
+    context_time = 0;
+  inst->last_nke_success = context_time + SCH_GetLastEventMonoTime();
+
+  DEBUG_LOG("Loaded %d cookies for %s", i, filename);
+  return;
+
+error:
+  DEBUG_LOG("Could not %s cookies for %s", "load", filename);
+  fclose(f);
+
+  memset(&inst->context, 0, sizeof (inst->context));
+  inst->num_cookies = 0;
+}
+
+/* ================================================== */
+
+void
+NNC_DumpData(NNC_Instance inst)
+{
+  save_cookies(inst);
+}

nts_ntp_client.h

@@ -0,0 +1,48 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for client NTS-NTP authentication
+  */
+
+#ifndef GOT_NTS_NTP_CLIENT_H
+#define GOT_NTS_NTP_CLIENT_H
+
+#include "addressing.h"
+#include "ntp.h"
+
+typedef struct NNC_Instance_Record *NNC_Instance;
+
+extern NNC_Instance NNC_CreateInstance(IPSockAddr *nts_address, const char *name,
+                                                   const IPSockAddr *ntp_address);
+extern void NNC_DestroyInstance(NNC_Instance inst);
+extern int NNC_PrepareForAuth(NNC_Instance inst);
+extern int NNC_GenerateRequestAuth(NNC_Instance inst, NTP_Packet *packet,
+                                   NTP_PacketInfo *info);
+extern int NNC_CheckResponseAuth(NNC_Instance inst, NTP_Packet *packet,
+                                 NTP_PacketInfo *info);
+
+extern void NNC_ChangeAddress(NNC_Instance inst, IPAddr *address);
+
+extern void NNC_DumpData(NNC_Instance inst);
+
+#endif

nts_ntp_server.c

@@ -0,0 +1,260 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Server NTS-NTP authentication
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "nts_ntp_server.h"
+
+#include "conf.h"
+#include "logging.h"
+#include "memory.h"
+#include "ntp.h"
+#include "ntp_ext.h"
+#include "nts_ke_server.h"
+#include "nts_ntp.h"
+#include "nts_ntp_auth.h"
+#include "siv.h"
+#include "util.h"
+
+#define SERVER_SIV AEAD_AES_SIV_CMAC_256
+
+struct NtsServer {
+  SIV_Instance siv;
+  unsigned char nonce[NTS_MIN_UNPADDED_NONCE_LENGTH];
+  NKE_Cookie cookies[NTS_MAX_COOKIES];
+  int num_cookies;
+  NTP_int64 req_tx;
+};
+
+/* The server instance handling all requests */
+struct NtsServer *server;
+
+/* ================================================== */
+
+void
+NNS_Initialise(void)
+{
+  /* Create an NTS-NTP server instance only if NTS-KE server is enabled */
+  if (!CNF_GetNtsServerCertFile() || !CNF_GetNtsServerKeyFile()) {
+    server = NULL;
+    return;
+  }
+
+  server = Malloc(sizeof (struct NtsServer));
+  server->siv = SIV_CreateInstance(SERVER_SIV);
+}
+
+/* ================================================== */
+
+void
+NNS_Finalise(void)
+{
+  if (!server)
+    return;
+
+  SIV_DestroyInstance(server->siv);
+  Free(server);
+  server = NULL;
+}
+
+/* ================================================== */
+
+int
+NNS_CheckRequestAuth(NTP_Packet *packet, NTP_PacketInfo *info, uint32_t *kod)
+{
+  int ef_type, ef_body_length, ef_length, has_uniq_id = 0, has_auth = 0, has_cookie = 0;
+  int i, plaintext_length, parsed, requested_cookies, cookie_length = -1, auth_start = 0;
+  unsigned char plaintext[NTP_MAX_EXTENSIONS_LENGTH];
+  NKE_Context context;
+  NKE_Cookie cookie;
+  void *ef_body;
+
+  if (!server)
+    return 0;
+
+  *kod = 0;
+
+  server->num_cookies = 0;
+  server->req_tx = packet->transmit_ts;
+
+  if (info->ext_fields == 0 || info->mode != MODE_CLIENT)
+    return 0;
+
+  requested_cookies = 0;
+
+  for (parsed = NTP_HEADER_LENGTH; parsed < info->length; parsed += ef_length) {
+    if (!NEF_ParseField(packet, info->length, parsed,
+                        &ef_length, &ef_type, &ef_body, &ef_body_length))
+      break;
+
+    switch (ef_type) {
+      case NTP_EF_NTS_UNIQUE_IDENTIFIER:
+        has_uniq_id = 1;
+        break;
+      case NTP_EF_NTS_COOKIE:
+        if (has_cookie || ef_body_length > sizeof (cookie.cookie))
+          return 0;
+        cookie.length = ef_body_length;
+        memcpy(cookie.cookie, ef_body, ef_body_length);
+        has_cookie = 1;
+        /* Fall through */
+      case NTP_EF_NTS_COOKIE_PLACEHOLDER:
+        requested_cookies++;
+
+        if (cookie_length >= 0 && cookie_length != ef_body_length) {
+          DEBUG_LOG("Invalid cookie/placeholder length");
+          return 0;
+        }
+        cookie_length = ef_body_length;
+        break;
+      case NTP_EF_NTS_AUTH_AND_EEF:
+        auth_start = parsed;
+        has_auth = 1;
+        break;
+      default:
+        break;
+    }
+  }
+
+  if (!has_uniq_id || !has_cookie || !has_auth) {
+    DEBUG_LOG("Missing an NTS EF");
+    return 0;
+  }
+
+  if (!NKS_DecodeCookie(&cookie, &context)) {
+    *kod = NTP_KOD_NTS_NAK;
+    return 0;
+  }
+
+  if (context.algorithm != SERVER_SIV) {
+    DEBUG_LOG("Unexpected SIV");
+    return 0;
+  }
+
+  if (!SIV_SetKey(server->siv, context.c2s.key, context.c2s.length)) {
+    DEBUG_LOG("Could not set C2S key");
+    return 0;
+  }
+
+  if (!NNA_DecryptAuthEF(packet, info, server->siv, auth_start,
+                         plaintext, sizeof (plaintext), &plaintext_length)) {
+    *kod = NTP_KOD_NTS_NAK;
+    return 0;
+  }
+
+  for (parsed = 0; parsed < plaintext_length; parsed += ef_length) {
+    if (!NEF_ParseSingleField(plaintext, plaintext_length, parsed,
+                              &ef_length, &ef_type, &ef_body, &ef_body_length))
+      break;
+
+    switch (ef_type) {
+      case NTP_EF_NTS_COOKIE_PLACEHOLDER:
+        if (cookie_length != ef_body_length) {
+          DEBUG_LOG("Invalid cookie/placeholder length");
+          return 0;
+        }
+        requested_cookies++;
+        break;
+      default:
+        break;
+    }
+  }
+
+  if (!SIV_SetKey(server->siv, context.s2c.key, context.s2c.length)) {
+    DEBUG_LOG("Could not set S2C key");
+    return 0;
+  }
+
+  UTI_GetRandomBytes(server->nonce, sizeof (server->nonce));
+
+  server->num_cookies = MIN(NTS_MAX_COOKIES, requested_cookies);
+  for (i = 0; i < server->num_cookies; i++)
+    if (!NKS_GenerateCookie(&context, &server->cookies[i]))
+      return 0;
+
+  return 1;
+}
+
+/* ================================================== */
+
+int
+NNS_GenerateResponseAuth(NTP_Packet *request, NTP_PacketInfo *req_info,
+                         NTP_Packet *response, NTP_PacketInfo *res_info,
+                         uint32_t kod)
+{
+  int i, ef_type, ef_body_length, ef_length, parsed;
+  void *ef_body;
+  unsigned char plaintext[NTP_MAX_EXTENSIONS_LENGTH];
+  int plaintext_length;
+
+  if (!server || req_info->mode != MODE_CLIENT || res_info->mode != MODE_SERVER)
+    return 0;
+
+  /* Make sure this is a response to the expected request */
+  if (UTI_CompareNtp64(&server->req_tx, &request->transmit_ts) != 0)
+    assert(0);
+
+  for (parsed = NTP_HEADER_LENGTH; parsed < req_info->length; parsed += ef_length) {
+    if (!NEF_ParseField(request, req_info->length, parsed,
+                        &ef_length, &ef_type, &ef_body, &ef_body_length))
+      break;
+
+    switch (ef_type) {
+      case NTP_EF_NTS_UNIQUE_IDENTIFIER:
+        /* Copy the ID from the request */
+        if (!NEF_AddField(response, res_info, ef_type, ef_body, ef_body_length))
+          return 0;
+      default:
+        break;
+    }
+  }
+
+  /* NTS NAK response does not have any other fields */
+  if (kod)
+    return 1;
+
+  for (i = 0, plaintext_length = 0; i < server->num_cookies; i++) {
+    if (!NEF_SetField(plaintext, sizeof (plaintext), plaintext_length,
+                      NTP_EF_NTS_COOKIE, &server->cookies[i].cookie,
+                      server->cookies[i].length, &ef_length))
+      return 0;
+
+    plaintext_length += ef_length;
+    assert(plaintext_length <= sizeof (plaintext));
+  }
+
+  server->num_cookies = 0;
+
+  if (!NNA_GenerateAuthEF(response, res_info, server->siv,
+                          server->nonce, sizeof (server->nonce),
+                          plaintext, plaintext_length,
+                          req_info->length - res_info->length))
+    return 0;
+
+  return 1;
+}

nts_ntp_server.h

@@ -0,0 +1,40 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Header file for server NTS-NTP authentication
+  */
+
+#ifndef GOT_NTS_NTP_SERVER_H
+#define GOT_NTS_NTP_SERVER_H
+
+#include "ntp.h"
+
+extern void NNS_Initialise(void);
+extern void NNS_Finalise(void);
+
+extern int NNS_CheckRequestAuth(NTP_Packet *packet, NTP_PacketInfo *info, uint32_t *kod);
+extern int NNS_GenerateResponseAuth(NTP_Packet *request, NTP_PacketInfo *req_info,
+                                    NTP_Packet *response, NTP_PacketInfo *res_info,
+                                    uint32_t kod);
+
+#endif

pktlength.c

@@ -3,6 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2002
+ * Copyright (C) Miroslav Lichvar  2014-2016
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -33,145 +34,136 @@
 #include "util.h"
 #include "pktlength.h"
 
+#define PADDING_LENGTH_(request_length, reply_length) \
+  (uint16_t)((request_length) < (reply_length) ? (reply_length) - (request_length) : 0)
+
+#define PADDING_LENGTH(request_data, reply_data) \
+  PADDING_LENGTH_(offsetof(CMD_Request, request_data), offsetof(CMD_Reply, reply_data))
+
+#define REQ_LENGTH_ENTRY(request_data_field, reply_data_field) \
+  { offsetof(CMD_Request, data.request_data_field.EOR), \
+    PADDING_LENGTH(data.request_data_field.EOR, data.reply_data_field.EOR) }
+
+#define RPY_LENGTH_ENTRY(reply_data_field) \
+  offsetof(CMD_Reply, data.reply_data_field.EOR)
+
 /* ================================================== */
 
-static int
-command_unpadded_length(CMD_Request *r)
-{
-  int type;
-  type = ntohs(r->command);
-  if (type < 0 || type >= N_REQUEST_TYPES) {
-    return 0;
-  } else {
-    switch (type) {
-      case REQ_NULL:
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_ONLINE:
-        return offsetof(CMD_Request, data.online.EOR);
-      case REQ_OFFLINE:
-        return offsetof(CMD_Request, data.offline.EOR);
-      case REQ_BURST:
-        return offsetof(CMD_Request, data.burst.EOR);
-      case REQ_MODIFY_MINPOLL:
-        return offsetof(CMD_Request, data.modify_minpoll.EOR);
-      case REQ_MODIFY_MAXPOLL:
-        return offsetof(CMD_Request, data.modify_maxpoll.EOR);
-      case REQ_DUMP:
-        return offsetof(CMD_Request, data.dump.EOR);
-      case REQ_MODIFY_MAXDELAY:
-        return offsetof(CMD_Request, data.modify_maxdelay.EOR);
-      case REQ_MODIFY_MAXDELAYRATIO:
-        return offsetof(CMD_Request, data.modify_maxdelayratio.EOR);
-      case REQ_MODIFY_MAXDELAYDEVRATIO:
-        return offsetof(CMD_Request, data.modify_maxdelaydevratio.EOR);
-      case REQ_MODIFY_MAXUPDATESKEW:
-        return offsetof(CMD_Request, data.modify_maxupdateskew.EOR);
-      case REQ_MODIFY_MAKESTEP:
-        return offsetof(CMD_Request, data.modify_makestep.EOR);
-      case REQ_LOGON :
-        return offsetof(CMD_Request, data.logon.EOR);
-      case REQ_SETTIME :
-        return offsetof(CMD_Request, data.settime.EOR);
-      case REQ_LOCAL :
-        return offsetof(CMD_Request, data.local.EOR);
-      case REQ_MANUAL :
-        return offsetof(CMD_Request, data.manual.EOR);
-      case REQ_N_SOURCES :
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_SOURCE_DATA :
-        return offsetof(CMD_Request, data.source_data.EOR);
-      case REQ_REKEY :
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_ALLOW :
-        return offsetof(CMD_Request, data.allow_deny.EOR);
-      case REQ_ALLOWALL :
-        return offsetof(CMD_Request, data.allow_deny.EOR);
-      case REQ_DENY :
-        return offsetof(CMD_Request, data.allow_deny.EOR);
-      case REQ_DENYALL :
-        return offsetof(CMD_Request, data.allow_deny.EOR);
-      case REQ_CMDALLOW :
-        return offsetof(CMD_Request, data.allow_deny.EOR);
-      case REQ_CMDALLOWALL :
-        return offsetof(CMD_Request, data.allow_deny.EOR);
-      case REQ_CMDDENY :
-        return offsetof(CMD_Request, data.allow_deny.EOR);
-      case REQ_CMDDENYALL :
-        return offsetof(CMD_Request, data.allow_deny.EOR);
-      case REQ_ACCHECK :
-        return offsetof(CMD_Request, data.ac_check.EOR);
-      case REQ_CMDACCHECK :
-        return offsetof(CMD_Request, data.ac_check.EOR);
-      case REQ_ADD_SERVER :
-        return offsetof(CMD_Request, data.ntp_source.EOR);
-      case REQ_ADD_PEER :
-        return offsetof(CMD_Request, data.ntp_source.EOR);
-      case REQ_DEL_SOURCE :
-        return offsetof(CMD_Request, data.del_source.EOR);
-      case REQ_WRITERTC :
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_DFREQ :
-        return offsetof(CMD_Request, data.dfreq.EOR);
-      case REQ_DOFFSET :
-        return offsetof(CMD_Request, data.doffset.EOR);
-      case REQ_TRACKING :
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_SOURCESTATS :
-        return offsetof(CMD_Request, data.sourcestats.EOR);
-      case REQ_RTCREPORT :
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_TRIMRTC :
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_CYCLELOGS :
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_SUBNETS_ACCESSED :
-      case REQ_CLIENT_ACCESSES:
-        /* No longer supported */
-        return 0;
-      case REQ_CLIENT_ACCESSES_BY_INDEX:
-        return offsetof(CMD_Request, data.client_accesses_by_index.EOR);
-      case REQ_MANUAL_LIST:
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_MANUAL_DELETE:
-        return offsetof(CMD_Request, data.manual_delete.EOR);
-      case REQ_MAKESTEP:
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_ACTIVITY:
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_RESELECT:
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_RESELECTDISTANCE:
-        return offsetof(CMD_Request, data.reselect_distance.EOR);
-      case REQ_MODIFY_MINSTRATUM:
-        return offsetof(CMD_Request, data.modify_minstratum.EOR);
-      case REQ_MODIFY_POLLTARGET:
-        return offsetof(CMD_Request, data.modify_polltarget.EOR);
-      case REQ_SMOOTHING:
-        return offsetof(CMD_Request, data.null.EOR);
-      case REQ_SMOOTHTIME:
-        return offsetof(CMD_Request, data.smoothtime.EOR);
-      case REQ_REFRESH:
-        return offsetof(CMD_Request, data.null.EOR);
-      default:
-        /* If we fall through the switch, it most likely means we've forgotten to implement a new case */
-        assert(0);
-    }
-  }
+struct request_length {
+  uint16_t command;
+  uint16_t padding;
+};
 
-  /* Catch-all case */
-  return 0;
-
-}
+static const struct request_length request_lengths[] = {
+  REQ_LENGTH_ENTRY(null, null),                 /* NULL */
+  REQ_LENGTH_ENTRY(online, null),               /* ONLINE */
+  REQ_LENGTH_ENTRY(offline, null),              /* OFFLINE */
+  REQ_LENGTH_ENTRY(burst, null),                /* BURST */
+  REQ_LENGTH_ENTRY(modify_minpoll, null),       /* MODIFY_MINPOLL */
+  REQ_LENGTH_ENTRY(modify_maxpoll, null),       /* MODIFY_MAXPOLL */
+  REQ_LENGTH_ENTRY(dump, null),                 /* DUMP */
+  REQ_LENGTH_ENTRY(modify_maxdelay, null),      /* MODIFY_MAXDELAY */
+  REQ_LENGTH_ENTRY(modify_maxdelayratio, null), /* MODIFY_MAXDELAYRATIO */
+  REQ_LENGTH_ENTRY(modify_maxupdateskew, null), /* MODIFY_MAXUPDATESKEW */
+  REQ_LENGTH_ENTRY(logon, null),                /* LOGON */
+  REQ_LENGTH_ENTRY(settime, manual_timestamp),  /* SETTIME */
+  { 0, 0 },                                     /* LOCAL */
+  REQ_LENGTH_ENTRY(manual, null),               /* MANUAL */
+  REQ_LENGTH_ENTRY(null, n_sources),            /* N_SOURCES */
+  REQ_LENGTH_ENTRY(source_data, source_data),   /* SOURCE_DATA */
+  REQ_LENGTH_ENTRY(null, null),                 /* REKEY */
+  REQ_LENGTH_ENTRY(allow_deny, null),           /* ALLOW */
+  REQ_LENGTH_ENTRY(allow_deny, null),           /* ALLOWALL */
+  REQ_LENGTH_ENTRY(allow_deny, null),           /* DENY */
+  REQ_LENGTH_ENTRY(allow_deny, null),           /* DENYALL */
+  REQ_LENGTH_ENTRY(allow_deny, null),           /* CMDALLOW */
+  REQ_LENGTH_ENTRY(allow_deny, null),           /* CMDALLOWALL */
+  REQ_LENGTH_ENTRY(allow_deny, null),           /* CMDDENY */
+  REQ_LENGTH_ENTRY(allow_deny, null),           /* CMDDENYALL */
+  REQ_LENGTH_ENTRY(ac_check, null),             /* ACCHECK */
+  REQ_LENGTH_ENTRY(ac_check, null),             /* CMDACCHECK */
+  { 0, 0 },                                     /* ADD_SERVER */
+  { 0, 0 },                                     /* ADD_PEER */
+  REQ_LENGTH_ENTRY(del_source, null),           /* DEL_SOURCE */
+  REQ_LENGTH_ENTRY(null, null),                 /* WRITERTC */
+  REQ_LENGTH_ENTRY(dfreq, null),                /* DFREQ */
+  REQ_LENGTH_ENTRY(doffset, null),              /* DOFFSET */
+  REQ_LENGTH_ENTRY(null, tracking),             /* TRACKING */
+  REQ_LENGTH_ENTRY(sourcestats, sourcestats),   /* SOURCESTATS */
+  REQ_LENGTH_ENTRY(null, rtc),                  /* RTCREPORT */
+  REQ_LENGTH_ENTRY(null, null),                 /* TRIMRTC */
+  REQ_LENGTH_ENTRY(null, null),                 /* CYCLELOGS */
+  { 0, 0 },                                     /* SUBNETS_ACCESSED - not supported */
+  { 0, 0 },                                     /* CLIENT_ACCESSES - not supported */
+  { 0, 0 },                                     /* CLIENT_ACCESSES_BY_INDEX - not supported */
+  REQ_LENGTH_ENTRY(null, manual_list),          /* MANUAL_LIST */
+  REQ_LENGTH_ENTRY(manual_delete, null),        /* MANUAL_DELETE */
+  REQ_LENGTH_ENTRY(null, null),                 /* MAKESTEP */
+  REQ_LENGTH_ENTRY(null, activity),             /* ACTIVITY */
+  REQ_LENGTH_ENTRY(modify_minstratum, null),    /* MODIFY_MINSTRATUM */
+  REQ_LENGTH_ENTRY(modify_polltarget, null),    /* MODIFY_POLLTARGET */
+  REQ_LENGTH_ENTRY(modify_maxdelaydevratio, null), /* MODIFY_MAXDELAYDEVRATIO */
+  REQ_LENGTH_ENTRY(null, null),                 /* RESELECT */
+  REQ_LENGTH_ENTRY(reselect_distance, null),    /* RESELECTDISTANCE */
+  REQ_LENGTH_ENTRY(modify_makestep, null),      /* MODIFY_MAKESTEP */
+  REQ_LENGTH_ENTRY(null, smoothing),            /* SMOOTHING */
+  REQ_LENGTH_ENTRY(smoothtime, null),           /* SMOOTHTIME */
+  REQ_LENGTH_ENTRY(null, null),                 /* REFRESH */
+  REQ_LENGTH_ENTRY(null, server_stats),         /* SERVER_STATS */
+  REQ_LENGTH_ENTRY(client_accesses_by_index,
+                   client_accesses_by_index),   /* CLIENT_ACCESSES_BY_INDEX2 */
+  REQ_LENGTH_ENTRY(local, null),                /* LOCAL2 */
+  REQ_LENGTH_ENTRY(ntp_data, ntp_data),         /* NTP_DATA */
+  { 0, 0 },                                     /* ADD_SERVER2 */
+  { 0, 0 },                                     /* ADD_PEER2 */
+  { 0, 0 },                                     /* ADD_SERVER3 */
+  { 0, 0 },                                     /* ADD_PEER3 */
+  REQ_LENGTH_ENTRY(null, null),                 /* SHUTDOWN */
+  REQ_LENGTH_ENTRY(null, null),                 /* ONOFFLINE */
+  REQ_LENGTH_ENTRY(ntp_source, null),           /* ADD_SOURCE */
+  REQ_LENGTH_ENTRY(ntp_source_name,
+                   ntp_source_name),            /* NTP_SOURCE_NAME */
+  REQ_LENGTH_ENTRY(null, null),                 /* RESET */
+};
 
+static const uint16_t reply_lengths[] = {
+  0,                                            /* empty slot */
+  RPY_LENGTH_ENTRY(null),                       /* NULL */
+  RPY_LENGTH_ENTRY(n_sources),                  /* N_SOURCES */
+  RPY_LENGTH_ENTRY(source_data),                /* SOURCE_DATA */
+  0,                                            /* MANUAL_TIMESTAMP */
+  RPY_LENGTH_ENTRY(tracking),                   /* TRACKING */
+  RPY_LENGTH_ENTRY(sourcestats),                /* SOURCESTATS */
+  RPY_LENGTH_ENTRY(rtc),                        /* RTC */
+  0,                                            /* SUBNETS_ACCESSED - not supported */
+  0,                                            /* CLIENT_ACCESSES - not supported */
+  0,                                            /* CLIENT_ACCESSES_BY_INDEX - not supported */
+  0,                                            /* MANUAL_LIST - not supported */
+  RPY_LENGTH_ENTRY(activity),                   /* ACTIVITY */
+  RPY_LENGTH_ENTRY(smoothing),                  /* SMOOTHING */
+  RPY_LENGTH_ENTRY(server_stats),               /* SERVER_STATS */
+  RPY_LENGTH_ENTRY(client_accesses_by_index),   /* CLIENT_ACCESSES_BY_INDEX2 */
+  RPY_LENGTH_ENTRY(ntp_data),                   /* NTP_DATA */
+  RPY_LENGTH_ENTRY(manual_timestamp),           /* MANUAL_TIMESTAMP2 */
+  RPY_LENGTH_ENTRY(manual_list),                /* MANUAL_LIST2 */
+  RPY_LENGTH_ENTRY(ntp_source_name),            /* NTP_SOURCE_NAME */
+};
 
 /* ================================================== */
 
 int
 PKL_CommandLength(CMD_Request *r)
 {
+  uint32_t type;
   int command_length;
 
-  command_length = command_unpadded_length(r);
+  assert(sizeof (request_lengths) / sizeof (request_lengths[0]) == N_REQUEST_TYPES);
+
+  type = ntohs(r->command);
+  if (type >= N_REQUEST_TYPES)
+    return 0;
+
+  command_length = request_lengths[type].command;
   if (!command_length)
     return 0;
 
@@ -180,139 +172,20 @@ PKL_CommandLength(CMD_Request *r)
 
 /* ================================================== */
 
-#define PADDING_LENGTH_(request_length, reply_length) \
-  ((request_length) < (reply_length) ? (reply_length) - (request_length) : 0)
-
-#define PADDING_LENGTH(request_data, reply_data) \
-  PADDING_LENGTH_(offsetof(CMD_Request, request_data), offsetof(CMD_Reply, reply_data))
-
 int
 PKL_CommandPaddingLength(CMD_Request *r)
 {
-  int type;
+  uint32_t type;
 
   if (r->version < PROTO_VERSION_PADDING)
     return 0;
 
   type = ntohs(r->command);
 
-  if (type < 0 || type >= N_REQUEST_TYPES)
+  if (type >= N_REQUEST_TYPES)
     return 0;
 
-  switch (type) {
-    case REQ_NULL:
-      return PADDING_LENGTH(data, data.null.EOR);
-    case REQ_ONLINE:
-      return PADDING_LENGTH(data.online.EOR, data.null.EOR);
-    case REQ_OFFLINE:
-      return PADDING_LENGTH(data.offline.EOR, data.null.EOR);
-    case REQ_BURST:
-      return PADDING_LENGTH(data.burst.EOR, data.null.EOR);
-    case REQ_MODIFY_MINPOLL:
-      return PADDING_LENGTH(data.modify_minpoll.EOR, data.null.EOR);
-    case REQ_MODIFY_MAXPOLL:
-      return PADDING_LENGTH(data.modify_maxpoll.EOR, data.null.EOR);
-    case REQ_DUMP:
-      return PADDING_LENGTH(data.dump.EOR, data.null.EOR);
-    case REQ_MODIFY_MAXDELAY:
-      return PADDING_LENGTH(data.modify_maxdelay.EOR, data.null.EOR);
-    case REQ_MODIFY_MAXDELAYRATIO:
-      return PADDING_LENGTH(data.modify_maxdelayratio.EOR, data.null.EOR);
-    case REQ_MODIFY_MAXDELAYDEVRATIO:
-      return PADDING_LENGTH(data.modify_maxdelaydevratio.EOR, data.null.EOR);
-    case REQ_MODIFY_MAXUPDATESKEW:
-      return PADDING_LENGTH(data.modify_maxupdateskew.EOR, data.null.EOR);
-    case REQ_MODIFY_MAKESTEP:
-      return PADDING_LENGTH(data.modify_makestep.EOR, data.null.EOR);
-    case REQ_LOGON:
-      return PADDING_LENGTH(data.logon.EOR, data.null.EOR);
-    case REQ_SETTIME:
-      return PADDING_LENGTH(data.settime.EOR, data.manual_timestamp.EOR);
-    case REQ_LOCAL:
-      return PADDING_LENGTH(data.local.EOR, data.null.EOR);
-    case REQ_MANUAL:
-      return PADDING_LENGTH(data.manual.EOR, data.null.EOR);
-    case REQ_N_SOURCES:
-      return PADDING_LENGTH(data.null.EOR, data.n_sources.EOR);
-    case REQ_SOURCE_DATA:
-      return PADDING_LENGTH(data.source_data.EOR, data.source_data.EOR);
-    case REQ_REKEY:
-      return PADDING_LENGTH(data.null.EOR, data.null.EOR);
-    case REQ_ALLOW:
-      return PADDING_LENGTH(data.allow_deny.EOR, data.null.EOR);
-    case REQ_ALLOWALL:
-      return PADDING_LENGTH(data.allow_deny.EOR, data.null.EOR);
-    case REQ_DENY:
-      return PADDING_LENGTH(data.allow_deny.EOR, data.null.EOR);
-    case REQ_DENYALL:
-      return PADDING_LENGTH(data.allow_deny.EOR, data.null.EOR);
-    case REQ_CMDALLOW:
-      return PADDING_LENGTH(data.allow_deny.EOR, data.null.EOR);
-    case REQ_CMDALLOWALL:
-      return PADDING_LENGTH(data.allow_deny.EOR, data.null.EOR);
-    case REQ_CMDDENY:
-      return PADDING_LENGTH(data.allow_deny.EOR, data.null.EOR);
-    case REQ_CMDDENYALL:
-      return PADDING_LENGTH(data.allow_deny.EOR, data.null.EOR);
-    case REQ_ACCHECK:
-      return PADDING_LENGTH(data.ac_check.EOR, data.null.EOR);
-    case REQ_CMDACCHECK:
-      return PADDING_LENGTH(data.ac_check.EOR, data.null.EOR);
-    case REQ_ADD_SERVER:
-      return PADDING_LENGTH(data.ntp_source.EOR, data.null.EOR);
-    case REQ_ADD_PEER:
-      return PADDING_LENGTH(data.ntp_source.EOR, data.null.EOR);
-    case REQ_DEL_SOURCE:
-      return PADDING_LENGTH(data.del_source.EOR, data.null.EOR);
-    case REQ_WRITERTC:
-      return PADDING_LENGTH(data.null.EOR, data.null.EOR);
-    case REQ_DFREQ:
-      return PADDING_LENGTH(data.dfreq.EOR, data.null.EOR);
-    case REQ_DOFFSET:
-      return PADDING_LENGTH(data.doffset.EOR, data.null.EOR);
-    case REQ_TRACKING:
-      return PADDING_LENGTH(data.null.EOR, data.tracking.EOR);
-    case REQ_SOURCESTATS:
-      return PADDING_LENGTH(data.sourcestats.EOR, data.sourcestats.EOR);
-    case REQ_RTCREPORT:
-      return PADDING_LENGTH(data.null.EOR, data.rtc.EOR);
-    case REQ_TRIMRTC:
-      return PADDING_LENGTH(data.null.EOR, data.null.EOR);
-    case REQ_CYCLELOGS:
-      return PADDING_LENGTH(data.null.EOR, data.null.EOR);
-    case REQ_SUBNETS_ACCESSED:
-    case REQ_CLIENT_ACCESSES:
-      /* No longer supported */
-      return 0;
-    case REQ_CLIENT_ACCESSES_BY_INDEX:
-      return PADDING_LENGTH(data.client_accesses_by_index.EOR, data.client_accesses_by_index.EOR);
-    case REQ_MANUAL_LIST:
-      return PADDING_LENGTH(data.null.EOR, data.manual_list.EOR);
-    case REQ_MANUAL_DELETE:
-      return PADDING_LENGTH(data.manual_delete.EOR, data.null.EOR);
-    case REQ_MAKESTEP:
-      return PADDING_LENGTH(data.null.EOR, data.null.EOR);
-    case REQ_ACTIVITY:
-      return PADDING_LENGTH(data.null.EOR, data.activity.EOR);
-    case REQ_RESELECT:
-      return PADDING_LENGTH(data.null.EOR, data.null.EOR);
-    case REQ_RESELECTDISTANCE:
-      return PADDING_LENGTH(data.reselect_distance.EOR, data.null.EOR);
-    case REQ_MODIFY_MINSTRATUM:
-      return PADDING_LENGTH(data.modify_minstratum.EOR, data.null.EOR);
-    case REQ_MODIFY_POLLTARGET:
-      return PADDING_LENGTH(data.modify_polltarget.EOR, data.null.EOR);
-    case REQ_SMOOTHING:
-      return PADDING_LENGTH(data.null.EOR, data.smoothing.EOR);
-    case REQ_SMOOTHTIME:
-      return PADDING_LENGTH(data.smoothtime.EOR, data.null.EOR);
-    case REQ_REFRESH:
-      return PADDING_LENGTH(data.null.EOR, data.null.EOR);
-    default:
-      /* If we fall through the switch, it most likely means we've forgotten to implement a new case */
-      assert(0);
-      return 0;
-  }
+  return request_lengths[ntohs(r->command)].padding;
 }
 
 /* ================================================== */
@@ -320,65 +193,17 @@ PKL_CommandPaddingLength(CMD_Request *r)
 int
 PKL_ReplyLength(CMD_Reply *r)
 {
-  int type;
-  type = ntohs(r->reply);
-  /* Note that reply type codes start from 1, not 0 */
-  if (type < 1 || type >= N_REPLY_TYPES) {
-    return 0;
-  } else {
-    switch (type) {
-      case RPY_NULL:
-        return offsetof(CMD_Reply, data.null.EOR);
-      case RPY_N_SOURCES:
-        return offsetof(CMD_Reply, data.n_sources.EOR);
-      case RPY_SOURCE_DATA:
-        return offsetof(CMD_Reply, data.source_data.EOR);
-      case RPY_MANUAL_TIMESTAMP:
-        return offsetof(CMD_Reply, data.manual_timestamp.EOR);
-      case RPY_TRACKING:
-        return offsetof(CMD_Reply, data.tracking.EOR);
-      case RPY_SOURCESTATS:
-        return offsetof(CMD_Reply, data.sourcestats.EOR);
-      case RPY_RTC:
-        return offsetof(CMD_Reply, data.rtc.EOR);
-      case RPY_SUBNETS_ACCESSED :
-      case RPY_CLIENT_ACCESSES:
-        /* No longer supported */
-        return 0;
-      case RPY_CLIENT_ACCESSES_BY_INDEX:
-        {
-          unsigned long nc = ntohl(r->data.client_accesses_by_index.n_clients);
-          if (r->status == htons(STT_SUCCESS)) {
-            if (nc > MAX_CLIENT_ACCESSES)
-              return 0;
-            return (offsetof(CMD_Reply, data.client_accesses_by_index.clients) +
-                    nc * sizeof(RPY_ClientAccesses_Client));
-          } else {
-            return offsetof(CMD_Reply, data);
-          }
-        }
-      case RPY_MANUAL_LIST:
-        {
-          unsigned long ns = ntohl(r->data.manual_list.n_samples);
-          if (ns > MAX_MANUAL_LIST_SAMPLES)
-            return 0;
-          if (r->status == htons(STT_SUCCESS)) {
-            return (offsetof(CMD_Reply, data.manual_list.samples) +
-                    ns * sizeof(RPY_ManualListSample));
-          } else {
-            return offsetof(CMD_Reply, data);
-          }
-        }
-      case RPY_ACTIVITY:
-        return offsetof(CMD_Reply, data.activity.EOR);
-      case RPY_SMOOTHING:
-        return offsetof(CMD_Reply, data.smoothing.EOR);
-      default:
-        assert(0);
-    }
-  }
+  uint32_t type;
 
-  return 0;
+  assert(sizeof (reply_lengths) / sizeof (reply_lengths[0]) == N_REPLY_TYPES);
+
+  type = ntohs(r->reply);
+
+  /* Note that reply type codes start from 1, not 0 */
+  if (type < 1 || type >= N_REPLY_TYPES)
+    return 0;
+
+  return reply_lengths[type];
 }
 
 /* ================================================== */

privops.c

@@ -0,0 +1,694 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Bryan Christianson 2015
+ * Copyright (C) Miroslav Lichvar  2017
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ **********************************************************************
+
+  =======================================================================
+
+  Perform privileged operations over a unix socket to a privileged fork.
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "conf.h"
+#include "nameserv.h"
+#include "logging.h"
+#include "privops.h"
+#include "socket.h"
+#include "util.h"
+
+#define OP_ADJUSTTIME     1024
+#define OP_ADJUSTTIMEX    1025
+#define OP_SETTIME        1026
+#define OP_BINDSOCKET     1027
+#define OP_NAME2IPADDRESS 1028
+#define OP_RELOADDNS      1029
+#define OP_QUIT           1099
+
+union sockaddr_in46 {
+  struct sockaddr_in in4;
+#ifdef FEAT_IPV6
+  struct sockaddr_in6 in6;
+#endif
+  struct sockaddr u;
+};
+
+/* daemon request structs */
+
+typedef struct {
+  struct timeval tv;
+} ReqAdjustTime;
+
+#ifdef PRIVOPS_ADJUSTTIMEX
+typedef struct {
+  struct timex tmx;
+} ReqAdjustTimex;
+#endif
+
+typedef struct {
+  struct timeval tv;
+} ReqSetTime;
+
+typedef struct {
+  int sock;
+  socklen_t sa_len;
+  union sockaddr_in46 sa;
+} ReqBindSocket;
+
+typedef struct {
+  char name[256];
+} ReqName2IPAddress;
+
+typedef struct {
+  int op;
+  union {
+    ReqAdjustTime adjust_time;
+#ifdef PRIVOPS_ADJUSTTIMEX
+    ReqAdjustTimex adjust_timex;
+#endif
+    ReqSetTime set_time;
+    ReqBindSocket bind_socket;
+#ifdef PRIVOPS_NAME2IPADDRESS
+    ReqName2IPAddress name_to_ipaddress;
+#endif
+  } data;
+} PrvRequest;
+
+/* helper response structs */
+
+typedef struct {
+  struct timeval tv;
+} ResAdjustTime;
+
+#ifdef PRIVOPS_ADJUSTTIMEX
+typedef struct {
+  struct timex tmx;
+} ResAdjustTimex;
+#endif
+
+typedef struct {
+  IPAddr addresses[DNS_MAX_ADDRESSES];
+} ResName2IPAddress;
+
+typedef struct {
+  char msg[256];
+} ResFatalMsg;
+
+typedef struct {
+  int fatal_error;
+  int rc;
+  int res_errno;
+  union {
+    ResFatalMsg fatal_msg;
+    ResAdjustTime adjust_time;
+#ifdef PRIVOPS_ADJUSTTIMEX
+    ResAdjustTimex adjust_timex;
+#endif
+#ifdef PRIVOPS_NAME2IPADDRESS
+    ResName2IPAddress name_to_ipaddress;
+#endif
+  } data;
+} PrvResponse;
+
+static int helper_fd;
+static pid_t helper_pid;
+
+static int
+have_helper(void)
+{
+  return helper_fd >= 0;
+}
+
+/* ======================================================================= */
+
+/* HELPER - prepare fatal error for daemon */
+static void
+res_fatal(PrvResponse *res, const char *fmt, ...)
+{
+  va_list ap;
+
+  res->fatal_error = 1;
+  va_start(ap, fmt);
+  vsnprintf(res->data.fatal_msg.msg, sizeof (res->data.fatal_msg.msg), fmt, ap);
+  va_end(ap);
+}
+
+/* ======================================================================= */
+
+/* HELPER - send response to the fd */
+
+static int
+send_response(int fd, const PrvResponse *res)
+{
+  if (SCK_Send(fd, res, sizeof (*res), 0) != sizeof (*res))
+    return 0;
+
+  return 1;
+}
+
+/* ======================================================================= */
+/* receive daemon request plus optional file descriptor over a unix socket */
+
+static int
+receive_from_daemon(int fd, PrvRequest *req)
+{
+  SCK_Message *message;
+
+  message = SCK_ReceiveMessage(fd, SCK_FLAG_MSG_DESCRIPTOR);
+  if (!message || message->length != sizeof (*req))
+    return 0;
+
+  memcpy(req, message->data, sizeof (*req));
+
+  if (req->op == OP_BINDSOCKET) {
+    req->data.bind_socket.sock = message->descriptor;
+
+    /* return error if valid descriptor not found */
+    if (req->data.bind_socket.sock < 0)
+      return 0;
+  } else if (message->descriptor >= 0) {
+    SCK_CloseSocket(message->descriptor);
+    return 0;
+  }
+
+  return 1;
+}
+
+/* ======================================================================= */
+
+/* HELPER - perform adjtime() */
+
+#ifdef PRIVOPS_ADJUSTTIME
+static void
+do_adjust_time(const ReqAdjustTime *req, PrvResponse *res)
+{
+  res->rc = adjtime(&req->tv, &res->data.adjust_time.tv);
+  if (res->rc)
+    res->res_errno = errno;
+}
+#endif
+
+/* ======================================================================= */
+
+/* HELPER - perform ntp_adjtime() */
+
+#ifdef PRIVOPS_ADJUSTTIMEX
+static void
+do_adjust_timex(const ReqAdjustTimex *req, PrvResponse *res)
+{
+  res->data.adjust_timex.tmx = req->tmx;
+  res->rc = ntp_adjtime(&res->data.adjust_timex.tmx);
+  if (res->rc < 0)
+    res->res_errno = errno;
+}
+#endif
+
+/* ======================================================================= */
+
+/* HELPER - perform settimeofday() */
+
+#ifdef PRIVOPS_SETTIME
+static void
+do_set_time(const ReqSetTime *req, PrvResponse *res)
+{
+  res->rc = settimeofday(&req->tv, NULL);
+  if (res->rc)
+    res->res_errno = errno;
+}
+#endif
+
+/* ======================================================================= */
+
+/* HELPER - perform bind() */
+
+#ifdef PRIVOPS_BINDSOCKET
+static void
+do_bind_socket(ReqBindSocket *req, PrvResponse *res)
+{
+  IPSockAddr ip_saddr;
+  int sock_fd;
+  struct sockaddr *sa;
+  socklen_t sa_len;
+
+  sa = &req->sa.u;
+  sa_len = req->sa_len;
+  sock_fd = req->sock;
+
+  SCK_SockaddrToIPSockAddr(sa, sa_len, &ip_saddr);
+  if (ip_saddr.port != 0 && ip_saddr.port != CNF_GetNTPPort() &&
+      ip_saddr.port != CNF_GetAcquisitionPort()) {
+    SCK_CloseSocket(sock_fd);
+    res_fatal(res, "Invalid port %d", ip_saddr.port);
+    return;
+  }
+
+  res->rc = bind(sock_fd, sa, sa_len);
+  if (res->rc)
+    res->res_errno = errno;
+
+  /* sock is still open on daemon side, but we're done with it in the helper */
+  SCK_CloseSocket(sock_fd);
+}
+#endif
+
+/* ======================================================================= */
+
+/* HELPER - perform DNS_Name2IPAddress() */
+
+#ifdef PRIVOPS_NAME2IPADDRESS
+static void
+do_name_to_ipaddress(ReqName2IPAddress *req, PrvResponse *res)
+{
+  /* make sure the string is terminated */
+  req->name[sizeof (req->name) - 1] = '\0';
+
+  res->rc = DNS_Name2IPAddress(req->name, res->data.name_to_ipaddress.addresses,
+                               DNS_MAX_ADDRESSES);
+}
+#endif
+
+/* ======================================================================= */
+
+/* HELPER - perform DNS_Reload() */
+
+#ifdef PRIVOPS_RELOADDNS
+static void
+do_reload_dns(PrvResponse *res)
+{
+  DNS_Reload();
+  res->rc = 0;
+}
+#endif
+
+/* ======================================================================= */
+
+/* HELPER - main loop - action requests from the daemon */
+
+static void
+helper_main(int fd)
+{
+  PrvRequest req;
+  PrvResponse res;
+  int quit = 0;
+
+  while (!quit) {
+    if (!receive_from_daemon(fd, &req))
+      /* read error or closed input - we cannot recover - give up */
+      break;
+
+    memset(&res, 0, sizeof (res));
+
+    switch (req.op) {
+#ifdef PRIVOPS_ADJUSTTIME
+      case OP_ADJUSTTIME:
+        do_adjust_time(&req.data.adjust_time, &res);
+        break;
+#endif
+#ifdef PRIVOPS_ADJUSTTIMEX
+      case OP_ADJUSTTIMEX:
+        do_adjust_timex(&req.data.adjust_timex, &res);
+        break;
+#endif
+#ifdef PRIVOPS_SETTIME
+      case OP_SETTIME:
+        do_set_time(&req.data.set_time, &res);
+        break;
+#endif
+#ifdef PRIVOPS_BINDSOCKET
+      case OP_BINDSOCKET:
+        do_bind_socket(&req.data.bind_socket, &res);
+        break;
+#endif
+#ifdef PRIVOPS_NAME2IPADDRESS
+      case OP_NAME2IPADDRESS:
+        do_name_to_ipaddress(&req.data.name_to_ipaddress, &res);
+        break;
+#endif
+#ifdef PRIVOPS_RELOADDNS
+      case OP_RELOADDNS:
+        do_reload_dns(&res);
+        break;
+#endif
+      case OP_QUIT:
+        quit = 1;
+        continue;
+
+      default:
+        res_fatal(&res, "Unexpected operator %d", req.op);
+        break;
+    }
+
+    send_response(fd, &res);
+  }
+
+  SCK_CloseSocket(fd);
+  exit(0);
+}
+
+/* ======================================================================= */
+
+/* DAEMON - receive helper response */
+
+static void
+receive_response(PrvResponse *res)
+{
+  int resp_len;
+
+  resp_len = SCK_Receive(helper_fd, res, sizeof (*res), 0);
+  if (resp_len < 0)
+    LOG_FATAL("Could not read from helper : %s", strerror(errno));
+  if (resp_len != sizeof (*res))
+    LOG_FATAL("Invalid helper response");
+
+  if (res->fatal_error)
+    LOG_FATAL("Error in helper : %s", res->data.fatal_msg.msg);
+
+  DEBUG_LOG("Received response rc=%d", res->rc);
+
+  /* if operation failed in the helper, set errno so daemon can print log message */
+  if (res->res_errno)
+    errno = res->res_errno;
+}
+
+/* ======================================================================= */
+
+/* DAEMON - send daemon request to the helper */
+
+static void
+send_request(PrvRequest *req)
+{
+  SCK_Message message;
+  int flags;
+
+  SCK_InitMessage(&message, SCK_ADDR_UNSPEC);
+
+  message.data = req;
+  message.length = sizeof (*req);
+  flags = 0;
+
+  if (req->op == OP_BINDSOCKET) {
+    /* send file descriptor as a control message */
+    message.descriptor = req->data.bind_socket.sock;
+    flags |= SCK_FLAG_MSG_DESCRIPTOR;
+  }
+
+  if (!SCK_SendMessage(helper_fd, &message, flags)) {
+    /* don't try to send another request from exit() */
+    helper_fd = -1;
+    LOG_FATAL("Could not send to helper : %s", strerror(errno));
+  }
+
+  DEBUG_LOG("Sent request op=%d", req->op);
+}
+
+/* ======================================================================= */
+
+/* DAEMON - send daemon request and wait for response */
+
+static void
+submit_request(PrvRequest *req, PrvResponse *res)
+{
+  send_request(req);
+  receive_response(res);
+}
+
+/* ======================================================================= */
+
+/* DAEMON - send the helper a request to exit and wait until it exits */
+
+static void
+stop_helper(void)
+{
+  PrvRequest req;
+  int status;
+
+  if (!have_helper())
+    return;
+
+  memset(&req, 0, sizeof (req));
+  req.op = OP_QUIT;
+  send_request(&req);
+
+  waitpid(helper_pid, &status, 0);
+}
+
+/* ======================================================================= */
+
+/* DAEMON - request adjtime() */
+
+#ifdef PRIVOPS_ADJUSTTIME
+int
+PRV_AdjustTime(const struct timeval *delta, struct timeval *olddelta)
+{
+  PrvRequest req;
+  PrvResponse res;
+
+  if (!have_helper() || delta == NULL)
+    /* helper is not running or read adjustment call */
+    return adjtime(delta, olddelta);
+
+  memset(&req, 0, sizeof (req));
+  req.op = OP_ADJUSTTIME;
+  req.data.adjust_time.tv = *delta;
+
+  submit_request(&req, &res);
+
+  if (olddelta)
+    *olddelta = res.data.adjust_time.tv;
+
+  return res.rc;
+}
+#endif
+
+/* ======================================================================= */
+
+/* DAEMON - request ntp_adjtime() */
+
+#ifdef PRIVOPS_ADJUSTTIMEX
+int
+PRV_AdjustTimex(struct timex *tmx)
+{
+  PrvRequest req;
+  PrvResponse res;
+
+  if (!have_helper())
+    return ntp_adjtime(tmx);
+
+  memset(&req, 0, sizeof (req));
+  req.op = OP_ADJUSTTIMEX;
+  req.data.adjust_timex.tmx = *tmx;
+
+  submit_request(&req, &res);
+
+  *tmx = res.data.adjust_timex.tmx;
+
+  return res.rc;
+}
+#endif
+
+/* ======================================================================= */
+
+/* DAEMON - request settimeofday() */
+
+#ifdef PRIVOPS_SETTIME
+int
+PRV_SetTime(const struct timeval *tp, const struct timezone *tzp)
+{
+  PrvRequest req;
+  PrvResponse res;
+
+  /* only support setting the time */
+  assert(tp != NULL);
+  assert(tzp == NULL);
+
+  if (!have_helper())
+    return settimeofday(tp, NULL);
+
+  memset(&req, 0, sizeof (req));
+  req.op = OP_SETTIME;
+  req.data.set_time.tv = *tp;
+
+  submit_request(&req, &res);
+
+  return res.rc;
+}
+#endif
+
+/* ======================================================================= */
+
+/* DAEMON - request bind() */
+
+#ifdef PRIVOPS_BINDSOCKET
+int
+PRV_BindSocket(int sock, struct sockaddr *address, socklen_t address_len)
+{
+  IPSockAddr ip_saddr;
+  PrvRequest req;
+  PrvResponse res;
+
+  SCK_SockaddrToIPSockAddr(address, address_len, &ip_saddr);
+  if (ip_saddr.port != 0 && ip_saddr.port != CNF_GetNTPPort() &&
+      ip_saddr.port != CNF_GetAcquisitionPort())
+    assert(0);
+
+  if (!have_helper())
+    return bind(sock, address, address_len);
+
+  memset(&req, 0, sizeof (req));
+  req.op = OP_BINDSOCKET;
+  req.data.bind_socket.sock = sock;
+  req.data.bind_socket.sa_len = address_len;
+  assert(address_len <= sizeof (req.data.bind_socket.sa));
+  memcpy(&req.data.bind_socket.sa.u, address, address_len);
+
+  submit_request(&req, &res);
+
+  return res.rc;
+}
+#endif
+
+/* ======================================================================= */
+
+/* DAEMON - request DNS_Name2IPAddress() */
+
+#ifdef PRIVOPS_NAME2IPADDRESS
+int
+PRV_Name2IPAddress(const char *name, IPAddr *ip_addrs, int max_addrs)
+{
+  PrvRequest req;
+  PrvResponse res;
+  int i;
+
+  if (!have_helper())
+    return DNS_Name2IPAddress(name, ip_addrs, max_addrs);
+
+  memset(&req, 0, sizeof (req));
+  req.op = OP_NAME2IPADDRESS;
+  if (snprintf(req.data.name_to_ipaddress.name, sizeof (req.data.name_to_ipaddress.name),
+               "%s", name) >= sizeof (req.data.name_to_ipaddress.name)) {
+    return DNS_Failure;
+  }
+
+  submit_request(&req, &res);
+
+  for (i = 0; i < max_addrs && i < DNS_MAX_ADDRESSES; i++)
+    ip_addrs[i] = res.data.name_to_ipaddress.addresses[i];
+
+  return res.rc;
+}
+#endif
+
+/* ======================================================================= */
+
+/* DAEMON - request res_init() */
+
+#ifdef PRIVOPS_RELOADDNS
+void
+PRV_ReloadDNS(void)
+{
+  PrvRequest req;
+  PrvResponse res;
+
+  if (!have_helper()) {
+    DNS_Reload();
+    return;
+  }
+
+  memset(&req, 0, sizeof (req));
+  req.op = OP_RELOADDNS;
+
+  submit_request(&req, &res);
+  assert(!res.rc);
+}
+#endif
+
+/* ======================================================================= */
+
+void
+PRV_Initialise(void)
+{
+  helper_fd = -1;
+}
+
+/* ======================================================================= */
+
+/* DAEMON - setup socket(s) then fork to run the helper */
+/* must be called before privileges are dropped */
+
+void
+PRV_StartHelper(void)
+{
+  pid_t pid;
+  int fd, sock_fd1, sock_fd2;
+
+  if (have_helper())
+    LOG_FATAL("Helper already running");
+
+  sock_fd1 = SCK_OpenUnixSocketPair(SCK_FLAG_BLOCK, &sock_fd2);
+  if (sock_fd1 < 0)
+    LOG_FATAL("Could not open socket pair");
+
+  pid = fork();
+  if (pid < 0)
+    LOG_FATAL("fork() failed : %s", strerror(errno));
+
+  if (pid == 0) {
+    /* child process */
+    SCK_CloseSocket(sock_fd1);
+
+    /* close other descriptors inherited from the parent process, except
+       stdin, stdout, and stderr */
+    for (fd = STDERR_FILENO + 1; fd < 1024; fd++) {
+      if (fd != sock_fd2)
+        close(fd);
+    }
+
+    /* ignore signals, the process will exit on OP_QUIT request */
+    UTI_SetQuitSignalsHandler(SIG_IGN, 1);
+
+    helper_main(sock_fd2);
+
+  } else {
+    /* parent process */
+    SCK_CloseSocket(sock_fd2);
+    helper_fd = sock_fd1;
+    helper_pid = pid;
+
+    /* stop the helper even when not exiting cleanly from the main function */
+    atexit(stop_helper);
+  }
+}
+
+/* ======================================================================= */
+
+/* DAEMON - graceful shutdown of the helper */
+
+void
+PRV_Finalise(void)
+{
+  if (!have_helper())
+    return;
+
+  stop_helper();
+  close(helper_fd);
+  helper_fd = -1;
+}

privops.h

@@ -0,0 +1,77 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Bryan Christianson 2015
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ **********************************************************************
+
+  =======================================================================
+
+  Perform privileged operations over a unix socket to a privileged fork.
+
+*/
+
+#ifndef GOT_PRIVOPS_H
+#define GOT_PRIVOPS_H
+
+#ifdef PRIVOPS_ADJUSTTIME
+int PRV_AdjustTime(const struct timeval *delta, struct timeval *olddelta);
+#else
+#define PRV_AdjustTime adjtime
+#endif
+
+#ifdef PRIVOPS_ADJUSTTIMEX
+int PRV_AdjustTimex(struct timex *txc);
+#else
+#define PRV_AdjustTimex ntp_adjtime
+#endif
+
+#ifdef PRIVOPS_SETTIME
+int PRV_SetTime(const struct timeval *tp, const struct timezone *tzp);
+#else
+#define PRV_SetTime settimeofday
+#endif
+
+#ifdef PRIVOPS_BINDSOCKET
+int PRV_BindSocket(int sock, struct sockaddr *address, socklen_t address_len);
+#else
+#define PRV_BindSocket bind
+#endif
+
+#ifdef PRIVOPS_NAME2IPADDRESS
+int PRV_Name2IPAddress(const char *name, IPAddr *ip_addrs, int max_addrs);
+#else
+#define PRV_Name2IPAddress DNS_Name2IPAddress
+#endif
+
+#ifdef PRIVOPS_RELOADDNS
+void PRV_ReloadDNS(void);
+#else
+#define PRV_ReloadDNS DNS_Reload
+#endif
+
+#ifdef PRIVOPS_HELPER
+void PRV_Initialise(void);
+void PRV_StartHelper(void);
+void PRV_Finalise(void);
+#else
+#define PRV_Initialise()
+#define PRV_StartHelper()
+#define PRV_Finalise()
+#endif
+
+#endif

refclock.h

@@ -37,16 +37,21 @@ typedef struct {
   int driver_poll;
   int poll;
   int filter_length;
+  int pps_forced;
   int pps_rate;
   int min_samples;
   int max_samples;
+  int sel_options;
+  int max_lock_age;
+  int stratum;
+  int tai;
   uint32_t ref_id;
   uint32_t lock_ref_id;
   double offset;
   double delay;
   double precision;
   double max_dispersion;
-  SRC_SelectOption sel_option;
+  double pulse_width;
 } RefclockParameters;
 
 typedef struct RCL_Instance_Record *RCL_Instance;
@@ -61,14 +66,19 @@ extern void RCL_Initialise(void);
 extern void RCL_Finalise(void);
 extern int RCL_AddRefclock(RefclockParameters *params);
 extern void RCL_StartRefclocks(void);
-extern void RCL_ReportSource(RPT_SourceReport *report, struct timeval *now);
+extern void RCL_ReportSource(RPT_SourceReport *report, struct timespec *now);
 
 /* functions used by drivers */
 extern void RCL_SetDriverData(RCL_Instance instance, void *data);
 extern void *RCL_GetDriverData(RCL_Instance instance);
 extern char *RCL_GetDriverParameter(RCL_Instance instance);
+extern void RCL_CheckDriverOptions(RCL_Instance instance, const char **options);
 extern char *RCL_GetDriverOption(RCL_Instance instance, char *name);
-extern int RCL_AddSample(RCL_Instance instance, struct timeval *sample_time, double offset, int leap);
-extern int RCL_AddPulse(RCL_Instance instance, struct timeval *pulse_time, double second);
+extern int RCL_AddSample(RCL_Instance instance, struct timespec *sample_time, double offset, int leap);
+extern int RCL_AddPulse(RCL_Instance instance, struct timespec *pulse_time, double second);
+extern int RCL_AddCookedPulse(RCL_Instance instance, struct timespec *cooked_time,
+                              double second, double dispersion, double raw_correction);
+extern double RCL_GetPrecision(RCL_Instance instance);
+extern int RCL_GetDriverPoll(RCL_Instance instance);
 
 #endif

refclock_phc.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2013
+ * Copyright (C) Miroslav Lichvar  2013, 2017
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -33,151 +33,137 @@
 
 #include "sysincl.h"
 
-#include <linux/ptp_clock.h>
-
 #include "refclock.h"
+#include "hwclock.h"
+#include "local.h"
 #include "logging.h"
+#include "memory.h"
 #include "util.h"
+#include "sched.h"
+#include "sys_linux.h"
 
-/* From linux/include/linux/posix-timers.h */
-#define CPUCLOCK_MAX            3
-#define CLOCKFD                 CPUCLOCK_MAX
-#define CLOCKFD_MASK            (CPUCLOCK_PERTHREAD_MASK|CPUCLOCK_CLOCK_MASK)
-
-#define FD_TO_CLOCKID(fd)       ((~(clockid_t) (fd) << 3) | CLOCKFD)
-
-#define NUM_READINGS 10
-
-static int no_sys_offset_ioctl = 0;
-
-struct phc_reading {
-  struct timespec sys_ts1;
-  struct timespec phc_ts;;
-  struct timespec sys_ts2;
+struct phc_instance {
+  int fd;
+  int mode;
+  int nocrossts;
+  int extpps;
+  int pin;
+  int channel;
+  HCL_Instance clock;
 };
 
-static double diff_ts(struct timespec *ts1, struct timespec *ts2)
-{
-  return (ts1->tv_sec - ts2->tv_sec) + (ts1->tv_nsec - ts2->tv_nsec) / 1e9;
-}
-
-static int read_phc_ioctl(struct phc_reading *readings, int phc_fd, int n)
-{
-#if defined(PTP_SYS_OFFSET) && NUM_READINGS <= PTP_MAX_SAMPLES
-  struct ptp_sys_offset sys_off;
-  int i;
-
-  /* Silence valgrind */
-  memset(&sys_off, 0, sizeof (sys_off));
-
-  sys_off.n_samples = n;
-  if (ioctl(phc_fd, PTP_SYS_OFFSET, &sys_off)) {
-    LOG(LOGS_ERR, LOGF_Refclock, "ioctl(PTP_SYS_OFFSET) failed : %s", strerror(errno));
-    return 0;
-  }
-
-  for (i = 0; i < n; i++) {
-    readings[i].sys_ts1.tv_sec = sys_off.ts[i * 2].sec;
-    readings[i].sys_ts1.tv_nsec = sys_off.ts[i * 2].nsec;
-    readings[i].phc_ts.tv_sec = sys_off.ts[i * 2 + 1].sec;
-    readings[i].phc_ts.tv_nsec = sys_off.ts[i * 2 + 1].nsec;
-    readings[i].sys_ts2.tv_sec = sys_off.ts[i * 2 + 2].sec;
-    readings[i].sys_ts2.tv_nsec = sys_off.ts[i * 2 + 2].nsec;
-  }
-
-  return 1;
-#else
-  /* Not available */
-  return 0;
-#endif
-}
-
-static int read_phc_user(struct phc_reading *readings, int phc_fd, int n)
-{
-  clockid_t phc_id;
-  int i;
-
-  phc_id = FD_TO_CLOCKID(phc_fd);
-
-  for (i = 0; i < n; i++) {
-    if (clock_gettime(CLOCK_REALTIME, &readings[i].sys_ts1) ||
-        clock_gettime(phc_id, &readings[i].phc_ts) ||
-        clock_gettime(CLOCK_REALTIME, &readings[i].sys_ts2)) {
-      LOG(LOGS_ERR, LOGF_Refclock, "clock_gettime() failed : %s", strerror(errno));
-      return 0;
-    }
-  }
-
-  return 1;
-}
+static void read_ext_pulse(int sockfd, int event, void *anything);
 
 static int phc_initialise(RCL_Instance instance)
 {
-  struct ptp_clock_caps caps;
-  int phc_fd;
-  char *path;
+  const char *options[] = {"nocrossts", "extpps", "pin", "channel", "clear", NULL};
+  struct phc_instance *phc;
+  int phc_fd, rising_edge;
+  char *path, *s;
+
+  RCL_CheckDriverOptions(instance, options);
 
   path = RCL_GetDriverParameter(instance);
  
-  phc_fd = open(path, O_RDONLY);
+  phc_fd = SYS_Linux_OpenPHC(path, 0);
   if (phc_fd < 0) {
-    LOG_FATAL(LOGF_Refclock, "open() failed on %s", path);
+    LOG_FATAL("Could not open PHC");
     return 0;
   }
 
-  /* Make sure it is a PHC */
-  if (ioctl(phc_fd, PTP_CLOCK_GETCAPS, &caps)) {
-    LOG_FATAL(LOGF_Refclock, "ioctl(PTP_CLOCK_GETCAPS) failed : %s", strerror(errno));
-    return 0;
+  phc = MallocNew(struct phc_instance);
+  phc->fd = phc_fd;
+  phc->mode = 0;
+  phc->nocrossts = RCL_GetDriverOption(instance, "nocrossts") ? 1 : 0;
+  phc->extpps = RCL_GetDriverOption(instance, "extpps") ? 1 : 0;
+
+  if (phc->extpps) {
+    s = RCL_GetDriverOption(instance, "pin");
+    phc->pin = s ? atoi(s) : 0;
+    s = RCL_GetDriverOption(instance, "channel");
+    phc->channel = s ? atoi(s) : 0;
+    rising_edge = RCL_GetDriverOption(instance, "clear") ? 0 : 1;
+    phc->clock = HCL_CreateInstance(0, 16, UTI_Log2ToDouble(RCL_GetDriverPoll(instance)));
+
+    if (!SYS_Linux_SetPHCExtTimestamping(phc->fd, phc->pin, phc->channel,
+                                         rising_edge, !rising_edge, 1))
+      LOG_FATAL("Could not enable external PHC timestamping");
+
+    SCH_AddFileHandler(phc->fd, SCH_FILE_INPUT, read_ext_pulse, instance);
+  } else {
+    phc->pin = phc->channel = 0;
+    phc->clock = NULL;
   }
 
-  UTI_FdSetCloexec(phc_fd);
-
-  RCL_SetDriverData(instance, (void *)(long)phc_fd);
+  RCL_SetDriverData(instance, phc);
   return 1;
 }
 
 static void phc_finalise(RCL_Instance instance)
 {
-  close((long)RCL_GetDriverData(instance));
+  struct phc_instance *phc;
+
+  phc = (struct phc_instance *)RCL_GetDriverData(instance);
+
+  if (phc->extpps) {
+    SCH_RemoveFileHandler(phc->fd);
+    SYS_Linux_SetPHCExtTimestamping(phc->fd, phc->pin, phc->channel, 0, 0, 0);
+    HCL_DestroyInstance(phc->clock);
+  }
+
+  close(phc->fd);
+  Free(phc);
+}
+
+static void read_ext_pulse(int fd, int event, void *anything)
+{
+  RCL_Instance instance;
+  struct phc_instance *phc;
+  struct timespec phc_ts, local_ts;
+  double local_err;
+  int channel;
+
+  instance = anything;
+  phc = RCL_GetDriverData(instance);
+
+  if (!SYS_Linux_ReadPHCExtTimestamp(phc->fd, &phc_ts, &channel))
+    return;
+
+  if (channel != phc->channel) {
+    DEBUG_LOG("Unexpected extts channel %d\n", channel);
+    return;
+  }
+
+  if (!HCL_CookTime(phc->clock, &phc_ts, &local_ts, &local_err))
+    return;
+
+  RCL_AddCookedPulse(instance, &local_ts, 1.0e-9 * local_ts.tv_nsec, local_err,
+                     UTI_DiffTimespecsToDouble(&phc_ts, &local_ts));
 }
 
 static int phc_poll(RCL_Instance instance)
 {
-  struct phc_reading readings[NUM_READINGS];
-  struct timeval tv;
-  double offset = 0.0, delay, best_delay = 0.0;
-  int i, phc_fd, best;
- 
-  phc_fd = (long)RCL_GetDriverData(instance);
+  struct phc_instance *phc;
+  struct timespec phc_ts, sys_ts, local_ts;
+  double offset, phc_err, local_err;
 
-  if (!no_sys_offset_ioctl) {
-    if (!read_phc_ioctl(readings, phc_fd, NUM_READINGS)) {
-      no_sys_offset_ioctl = 1;
-      return 0;
-    }
-  } else {
-    if (!read_phc_user(readings, phc_fd, NUM_READINGS))
-      return 0;
+  phc = (struct phc_instance *)RCL_GetDriverData(instance);
+
+  if (!SYS_Linux_GetPHCSample(phc->fd, phc->nocrossts, RCL_GetPrecision(instance),
+                              &phc->mode, &phc_ts, &sys_ts, &phc_err))
+    return 0;
+
+  if (phc->extpps) {
+    LCL_CookTime(&sys_ts, &local_ts, &local_err);
+    HCL_AccumulateSample(phc->clock, &phc_ts, &local_ts, phc_err + local_err);
+    return 0;
   }
 
-  /* Find the fastest reading */
-  for (i = 0; i < NUM_READINGS; i++) {
-    delay = diff_ts(&readings[i].sys_ts2, &readings[i].sys_ts1);
+  offset = UTI_DiffTimespecsToDouble(&phc_ts, &sys_ts);
 
-    if (!i || best_delay > delay) {
-      best = i;
-      best_delay = delay;
-    }
-  }
+  DEBUG_LOG("PHC offset: %+.9f err: %.9f", offset, phc_err);
 
-  offset = diff_ts(&readings[best].phc_ts, &readings[best].sys_ts2) + best_delay / 2.0;
-  tv.tv_sec = readings[best].sys_ts2.tv_sec;
-  tv.tv_usec = readings[best].sys_ts2.tv_nsec / 1000;
-
-  DEBUG_LOG(LOGF_Refclock, "PHC offset: %+.9f delay: %.9f", offset, best_delay);
-
-  return RCL_AddSample(instance, &tv, offset, LEAP_Normal);
+  return RCL_AddSample(instance, &sys_ts, offset, LEAP_Normal);
 }
 
 RefclockDriver RCL_PHC_driver = {

refclock_pps.c

@@ -48,48 +48,51 @@ struct pps_instance {
 };
 
 static int pps_initialise(RCL_Instance instance) {
+  const char *options[] = {"clear", NULL};
   pps_handle_t handle;
   pps_params_t params;
   struct pps_instance *pps;
   int fd, edge_clear, mode;
   char *path;
 
+  RCL_CheckDriverOptions(instance, options);
+
   path = RCL_GetDriverParameter(instance);
   edge_clear = RCL_GetDriverOption(instance, "clear") ? 1 : 0;
 
   fd = open(path, O_RDWR);
   if (fd < 0) {
-    LOG_FATAL(LOGF_Refclock, "open() failed on %s", path);
+    LOG_FATAL("Could not open %s : %s", path, strerror(errno));
     return 0;
   }
 
   UTI_FdSetCloexec(fd);
 
   if (time_pps_create(fd, &handle) < 0) {
-    LOG_FATAL(LOGF_Refclock, "time_pps_create() failed on %s", path);
+    LOG_FATAL("time_pps_create() failed on %s : %s", path, strerror(errno));
     return 0;
   }
 
   if (time_pps_getcap(handle, &mode) < 0) {
-    LOG_FATAL(LOGF_Refclock, "time_pps_getcap() failed on %s", path);
+    LOG_FATAL("time_pps_getcap() failed on %s : %s", path, strerror(errno));
     return 0;
   }
 
   if (time_pps_getparams(handle, &params) < 0) {
-    LOG_FATAL(LOGF_Refclock, "time_pps_getparams() failed on %s", path);
+    LOG_FATAL("time_pps_getparams() failed on %s : %s", path, strerror(errno));
     return 0;
   }
 
   if (!edge_clear) {
     if (!(mode & PPS_CAPTUREASSERT)) {
-      LOG_FATAL(LOGF_Refclock, "CAPTUREASSERT not supported on %s", path);
+      LOG_FATAL("CAPTUREASSERT not supported on %s", path);
       return 0;
     }
     params.mode |= PPS_CAPTUREASSERT;
     params.mode &= ~PPS_CAPTURECLEAR;
   } else {
     if (!(mode & PPS_CAPTURECLEAR)) {
-      LOG_FATAL(LOGF_Refclock, "CAPTURECLEAR not supported on %s", path);
+      LOG_FATAL("CAPTURECLEAR not supported on %s", path);
       return 0;
     }
     params.mode |= PPS_CAPTURECLEAR;
@@ -97,7 +100,7 @@ static int pps_initialise(RCL_Instance instance) {
   }
 
   if (time_pps_setparams(handle, &params) < 0) {
-    LOG_FATAL(LOGF_Refclock, "time_pps_setparams() failed on %s", path);
+    LOG_FATAL("time_pps_setparams() failed on %s : %s", path, strerror(errno));
     return 0;
   }
 
@@ -124,7 +127,6 @@ static int pps_poll(RCL_Instance instance)
 {
   struct pps_instance *pps; 
   struct timespec ts;
-  struct timeval tv;
   pps_info_t pps_info;
   pps_seq_t seq;
 
@@ -134,7 +136,7 @@ static int pps_poll(RCL_Instance instance)
   ts.tv_nsec = 0;
 
   if (time_pps_fetch(pps->handle, PPS_TSFMT_TSPEC, &pps_info, &ts) < 0) {
-    LOG(LOGS_ERR, LOGF_Refclock, "time_pps_fetch() failed : %s", strerror(errno));
+    LOG(LOGS_ERR, "time_pps_fetch() failed : %s", strerror(errno));
     return 0;
   }
 
@@ -146,17 +148,15 @@ static int pps_poll(RCL_Instance instance)
     ts = pps_info.clear_timestamp;
   }
 
-  if (seq == pps->last_seq || (ts.tv_sec == 0 && ts.tv_nsec == 0)) { 
-    DEBUG_LOG(LOGF_Refclock, "PPS sample ignored seq=%lu ts=%lu.%09lu",
-        seq, ts.tv_sec, ts.tv_nsec);
+  if (seq == pps->last_seq || UTI_IsZeroTimespec(&ts)) {
+    DEBUG_LOG("PPS sample ignored seq=%lu ts=%s",
+              (unsigned long)seq, UTI_TimespecToString(&ts));
     return 0;
   }
 
   pps->last_seq = seq;
-  tv.tv_sec = ts.tv_sec;
-  tv.tv_usec = ts.tv_nsec / 1000;
 
-  return RCL_AddPulse(instance, &tv, ts.tv_nsec / 1e9);
+  return RCL_AddPulse(instance, &ts, 1.0e-9 * ts.tv_nsec);
 }
 
 RefclockDriver RCL_PPS_driver = {

refclock_shm.c

@@ -59,23 +59,26 @@ struct shmTime {
 };
 
 static int shm_initialise(RCL_Instance instance) {
+  const char *options[] = {"perm", NULL};
   int id, param, perm;
   char *s;
   struct shmTime *shm;
 
+  RCL_CheckDriverOptions(instance, options);
+
   param = atoi(RCL_GetDriverParameter(instance));
   s = RCL_GetDriverOption(instance, "perm");
   perm = s ? strtol(s, NULL, 8) & 0777 : 0600;
 
   id = shmget(SHMKEY + param, sizeof (struct shmTime), IPC_CREAT | perm);
   if (id == -1) {
-    LOG_FATAL(LOGF_Refclock, "shmget() failed");
+    LOG_FATAL("shmget() failed : %s", strerror(errno));
     return 0;
   }
    
   shm = (struct shmTime *)shmat(id, 0, 0);
   if ((long)shm == -1) {
-    LOG_FATAL(LOGF_Refclock, "shmat() failed");
+    LOG_FATAL("shmat() failed : %s", strerror(errno));
     return 0;
   }
 
@@ -90,7 +93,7 @@ static void shm_finalise(RCL_Instance instance)
 
 static int shm_poll(RCL_Instance instance)
 {
-  struct timeval tv;
+  struct timespec receive_ts, clock_ts;
   struct shmTime t, *shm;
   double offset;
 
@@ -100,24 +103,30 @@ static int shm_poll(RCL_Instance instance)
   
   if ((t.mode == 1 && t.count != shm->count) ||
     !(t.mode == 0 || t.mode == 1) || !t.valid) {
-    DEBUG_LOG(LOGF_Refclock, "SHM sample ignored mode=%d count=%d valid=%d",
+    DEBUG_LOG("SHM sample ignored mode=%d count=%d valid=%d",
         t.mode, t.count, t.valid);
     return 0;
   }
 
   shm->valid = 0;
 
-  tv.tv_sec = t.receiveTimeStampSec;
-  tv.tv_usec = t.receiveTimeStampUSec;
+  receive_ts.tv_sec = t.receiveTimeStampSec;
+  clock_ts.tv_sec = t.clockTimeStampSec;
 
-  offset = t.clockTimeStampSec - t.receiveTimeStampSec;
   if (t.clockTimeStampNSec / 1000 == t.clockTimeStampUSec &&
-      t.receiveTimeStampNSec / 1000 == t.receiveTimeStampUSec)
-    offset += (t.clockTimeStampNSec - t.receiveTimeStampNSec) * 1e-9;
-  else
-    offset += (t.clockTimeStampUSec - t.receiveTimeStampUSec) * 1e-6;
+      t.receiveTimeStampNSec / 1000 == t.receiveTimeStampUSec) {
+    receive_ts.tv_nsec = t.receiveTimeStampNSec;
+    clock_ts.tv_nsec = t.clockTimeStampNSec;
+  } else {
+    receive_ts.tv_nsec = 1000 * t.receiveTimeStampUSec;
+    clock_ts.tv_nsec = 1000 * t.clockTimeStampUSec;
+  }
 
-  return RCL_AddSample(instance, &tv, offset, t.leap);
+  UTI_NormaliseTimespec(&clock_ts);
+  UTI_NormaliseTimespec(&receive_ts);
+  offset = UTI_DiffTimespecsToDouble(&clock_ts, &receive_ts);
+
+  return RCL_AddSample(instance, &receive_ts, offset, t.leap);
 }
 
 RefclockDriver RCL_SHM_driver = {

refclock_sock.c

@@ -33,84 +33,84 @@
 #include "logging.h"
 #include "util.h"
 #include "sched.h"
+#include "socket.h"
 
 #define SOCK_MAGIC 0x534f434b
 
 struct sock_sample {
+  /* Time of the measurement (system time) */
   struct timeval tv;
+
+  /* Offset between the true time and the system time (in seconds) */
   double offset;
+
+  /* Non-zero if the sample is from a PPS signal, i.e. another source
+     is needed to obtain seconds */
   int pulse;
+
+  /* 0 - normal, 1 - insert leap second, 2 - delete leap second */
   int leap;
+
+  /* Padding, ignored */
   int _pad;
+
+  /* Protocol identifier (0x534f434b) */
   int magic;
 };
 
-static void read_sample(void *anything)
+static void read_sample(int sockfd, int event, void *anything)
 {
   struct sock_sample sample;
+  struct timespec ts;
   RCL_Instance instance;
-  int sockfd, s;
+  int s;
 
   instance = (RCL_Instance)anything;
-  sockfd = (long)RCL_GetDriverData(instance);
 
   s = recv(sockfd, &sample, sizeof (sample), 0);
 
   if (s < 0) {
-    LOG(LOGS_ERR, LOGF_Refclock, "Could not read SOCK sample : %s",
-        strerror(errno));
+    DEBUG_LOG("Could not read SOCK sample : %s", strerror(errno));
     return;
   }
 
   if (s != sizeof (sample)) {
-    LOG(LOGS_WARN, LOGF_Refclock, "Unexpected length of SOCK sample : %d != %ld",
-        s, (long)sizeof (sample));
+    DEBUG_LOG("Unexpected length of SOCK sample : %d != %ld",
+              s, (long)sizeof (sample));
     return;
   }
 
   if (sample.magic != SOCK_MAGIC) {
-    LOG(LOGS_WARN, LOGF_Refclock, "Unexpected magic number in SOCK sample : %x != %x",
-        sample.magic, SOCK_MAGIC);
+    DEBUG_LOG("Unexpected magic number in SOCK sample : %x != %x",
+              (unsigned int)sample.magic, (unsigned int)SOCK_MAGIC);
     return;
   }
 
+  UTI_TimevalToTimespec(&sample.tv, &ts);
+  UTI_NormaliseTimespec(&ts);
+
   if (sample.pulse) {
-    RCL_AddPulse(instance, &sample.tv, sample.offset);
+    RCL_AddPulse(instance, &ts, sample.offset);
   } else {
-    RCL_AddSample(instance, &sample.tv, sample.offset, sample.leap);
+    RCL_AddSample(instance, &ts, sample.offset, sample.leap);
   }
 }
 
 static int sock_initialise(RCL_Instance instance)
 {
-  struct sockaddr_un s;
   int sockfd;
   char *path;
 
+  RCL_CheckDriverOptions(instance, NULL);
+
   path = RCL_GetDriverParameter(instance);
  
-  s.sun_family = AF_UNIX;
-  if (snprintf(s.sun_path, sizeof (s.sun_path), "%s", path) >= sizeof (s.sun_path)) {
-    LOG_FATAL(LOGF_Refclock, "path %s is too long", path);
-    return 0;
-  }
-
-  sockfd = socket(AF_UNIX, SOCK_DGRAM, 0);
-  if (sockfd < 0) {
-    LOG_FATAL(LOGF_Refclock, "socket() failed");
-    return 0;
-  }
-
-  UTI_FdSetCloexec(sockfd);
-
-  unlink(path);
-  if (bind(sockfd, (struct sockaddr *)&s, sizeof (s)) < 0) {
-    LOG_FATAL(LOGF_Refclock, "bind() failed");
-    return 0;
-  }
+  sockfd = SCK_OpenUnixDatagramSocket(NULL, path, 0);
+  if (sockfd < 0)
+    LOG_FATAL("Could not open socket %s", path);
 
   RCL_SetDriverData(instance, (void *)(long)sockfd);
-  SCH_AddInputFileHandler(sockfd, read_sample, instance);
+  SCH_AddFileHandler(sockfd, SCH_FILE_INPUT, read_sample, instance);
   return 1;
 }
 
@@ -119,8 +119,9 @@ static void sock_finalise(RCL_Instance instance)
   int sockfd;
 
   sockfd = (long)RCL_GetDriverData(instance);
-  SCH_RemoveInputFileHandler(sockfd);
-  close(sockfd);
+  SCH_RemoveFileHandler(sockfd);
+  SCK_RemoveSocket(sockfd);
+  SCK_CloseSocket(sockfd);
 }
 
 RefclockDriver RCL_SOCK_driver = {