doc: update NEWS

makefile: fix distclean target to not print errors
examples: improve configuration examples
2025-12-03 18:25:07 -05:00 · 2017-01-31 11:22:11 +01:00 · 2017-01-31 11:22:11 +01:00 · 2017-01-31 11:22:11 +01:00 · 2017-01-31 11:22:11 +01:00 · 2017-01-31 11:22:11 +01:00
46 changed files with 1113 additions and 448 deletions
--- a/Makefile.in
+++ b/Makefile.in
@@ -64,10 +64,10 @@ chronyc : $(CLI_OBJS)
 	$(CC) $(CFLAGS) -o chronyc $(CLI_OBJS) $(LDFLAGS) $(LIBS) $(EXTRA_CLI_LIBS)

 distclean : clean
-	-rm -f .DS_Store
-	-rm -f Makefile config.h config.log
 	$(MAKE) -C doc distclean
 	$(MAKE) -C test/unit distclean
+	-rm -f .DS_Store
+	-rm -f Makefile config.h config.log

 clean :
 	-rm -f *.o *.s chronyc chronyd core *~
--- a/15
+++ b/15
@@ -1,3 +1,18 @@
+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
 ==================

--- a/5
+++ b/5
@@ -16,7 +16,7 @@ and systems that do not run continuosly, or run on a virtual machine.

 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
+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
@@ -203,6 +203,9 @@ Kalle Olavi Niemitalo  <tosi@stekt.oulu.fi>
 Frank Otto <sandwichmacher@web.de>
    Handling arbitrary HZ values

+Denny Page <dennypage@me.com>
+    Advice on support for hardware timestamping
+
 Gautier PHILIPPON <gautier.philippon@ensimag.grenoble-inp.fr>
    Patch to add refresh command to chronyc

--- a/addressing.h
+++ b/addressing.h
@@ -50,8 +50,11 @@ typedef struct {
  unsigned short port;
 } NTP_Remote_Address;

+#define INVALID_IF_INDEX -1
+
 typedef struct {
  IPAddr ip_addr;
+  int if_index;
  int sock_fd;
 } NTP_Local_Address;

--- a/client.c
+++ b/client.c
@@ -3,6 +3,7 @@

 **********************************************************************
 * Copyright (C) Richard P. Curnow  1997-2003
+ * Copyright (C) Lonnie Abelbeck  2016
 * Copyright (C) Miroslav Lichvar  2009-2016
 * 
 * This program is free software; you can redistribute it and/or modify
@@ -1241,6 +1242,7 @@ give_help(void)
    "Other daemon commands:\0\0"
    "cyclelogs\0Close and re-open log files\0"
    "dump\0Dump all measurements to save files\0"
+    "rekey\0Re-read keys from key file\0"
    "\0\0"
    "Client commands:\0\0"
    "dns -n|+n\0Disable/enable resolving IP addresses to hostnames\0"
@@ -2214,8 +2216,8 @@ process_cmd_tracking(char *line)
               "Frequency       : %.3F\n"
               "Residual freq   : %+.3f ppm\n"
               "Skew            : %.3f ppm\n"
-               "Root delay      : %.6f seconds\n"
-               "Root dispersion : %.6f seconds\n"
+               "Root delay      : %.9f seconds\n"
+               "Root dispersion : %.9f seconds\n"
               "Update interval : %.1f seconds\n"
               "Leap status     : %L\n",
               (unsigned long)ref_id, name,
@@ -2723,7 +2725,8 @@ process_cmd_waitsync(char *line)
  max_skew_ppm = 0.0;
  interval = 10.0;

-  sscanf(line, "%d %lf %lf %lf", &max_tries, &max_correction, &max_skew_ppm, &interval);
+  if (sscanf(line, "%d %lf %lf %lf", &max_tries, &max_correction, &max_skew_ppm, &interval))
+    ;

  /* Don't allow shorter interval than 0.1 seconds */
  if (interval < 0.1)
@@ -2831,7 +2834,8 @@ process_cmd_keygen(char *line)
  snprintf(hash_name, sizeof (hash_name), "MD5");
 #endif

-  sscanf(line, "%u %16s %d", &id, hash_name, &bits);
+  if (sscanf(line, "%u %16s %d", &id, hash_name, &bits))
+    ;

  length = CLAMP(10, (bits + 7) / 8, sizeof (key));
  if (HSH_GetHashId(hash_name) < 0) {
@@ -3094,7 +3098,7 @@ static void
 display_gpl(void)
 {
    printf("chrony version %s\n"
-           "Copyright (C) 1997-2003, 2007, 2009-2016 Richard P. Curnow and others\n"
+           "Copyright (C) 1997-2003, 2007, 2009-2017 Richard P. Curnow and others\n"
           "chrony comes with ABSOLUTELY NO WARRANTY.  This is free software, and\n"
           "you are welcome to redistribute it under certain conditions.  See the\n"
           "GNU General Public License version 2 for details.\n\n",
--- a/conf.c
+++ b/conf.c
@@ -3,7 +3,7 @@

 **********************************************************************
 * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2009-2016
+ * 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
@@ -97,6 +97,7 @@ static double combine_limit = 3.0;

 static int cmd_port = DEFAULT_CANDM_PORT;

+static int raw_measurements = 0;
 static int do_log_measurements = 0;
 static int do_log_statistics = 0;
 static int do_log_tracking = 0;
@@ -223,13 +224,7 @@ static char *leapsec_tz = NULL;
 /* Name of the user to which will be dropped root privileges. */
 static char *user;

-typedef struct {
-  char *name;
-  double tx_comp;
-  double rx_comp;
-} HwTs_Interface;
-
-/* Array of HwTs_Interface */
+/* Array of CNF_HwTsInterface */
 static ARR_Instance hwts_interfaces;

 typedef struct {
@@ -333,7 +328,7 @@ CNF_Initialise(int r)
 {
  restarted = r;

-  hwts_interfaces = ARR_CreateInstance(sizeof (HwTs_Interface));
+  hwts_interfaces = ARR_CreateInstance(sizeof (CNF_HwTsInterface));

  init_sources = ARR_CreateInstance(sizeof (IPAddr));
  ntp_sources = ARR_CreateInstance(sizeof (NTP_Source));
@@ -360,7 +355,7 @@ CNF_Finalise(void)
  unsigned int i;

  for (i = 0; i < ARR_GetSize(hwts_interfaces); i++)
-    Free(((HwTs_Interface *)ARR_GetElement(hwts_interfaces, i))->name);
+    Free(((CNF_HwTsInterface *)ARR_GetElement(hwts_interfaces, i))->name);
  ARR_DestroyInstance(hwts_interfaces);

  for (i = 0; i < ARR_GetSize(ntp_sources); i++)
@@ -820,7 +815,10 @@ parse_log(char *line)
    log_name = line;
    line = CPS_SplitWord(line);
    if (*log_name) {
-      if (!strcmp(log_name, "measurements")) {
+      if (!strcmp(log_name, "rawmeasurements")) {
+        do_log_measurements = 1;
+        raw_measurements = 1;
+      } else if (!strcmp(log_name, "measurements")) {
        do_log_measurements = 1;
      } else if (!strcmp(log_name, "statistics")) {
        do_log_statistics = 1;
@@ -1251,7 +1249,7 @@ parse_tempcomp(char *line)
 static void
 parse_hwtimestamp(char *line)
 {
-  HwTs_Interface *iface;
+  CNF_HwTsInterface *iface;
  char *p;
  int n;

@@ -1265,18 +1263,30 @@ parse_hwtimestamp(char *line)

  iface = ARR_GetNewElement(hwts_interfaces);
  iface->name = Strdup(p);
+  iface->minpoll = 0;
+  iface->nocrossts = 0;
+  iface->precision = 100.0e-9;
  iface->tx_comp = 0.0;
  iface->rx_comp = 0.0;

  for (p = line; *p; line += n, p = line) {
    line = CPS_SplitWord(line);

-    if (!strcasecmp(p, "rxcomp")) {
+    if (!strcasecmp(p, "minpoll")) {
+      if (sscanf(line, "%d%n", &iface->minpoll, &n) != 1)
+        break;
+    } else if (!strcasecmp(p, "precision")) {
+      if (sscanf(line, "%lf%n", &iface->precision, &n) != 1)
+        break;
+    } else if (!strcasecmp(p, "rxcomp")) {
      if (sscanf(line, "%lf%n", &iface->rx_comp, &n) != 1)
        break;
    } else if (!strcasecmp(p, "txcomp")) {
      if (sscanf(line, "%lf%n", &iface->tx_comp, &n) != 1)
        break;
+    } else if (!strcasecmp(p, "nocrossts")) {
+      n = 0;
+      iface->nocrossts = 1;
    } else {
      break;
    }
@@ -1462,8 +1472,9 @@ CNF_GetDumpDir(void)
 /* ================================================== */

 int
-CNF_GetLogMeasurements(void)
+CNF_GetLogMeasurements(int *raw)
 {
+  *raw = raw_measurements;
  return do_log_measurements;
 }

@@ -1968,17 +1979,11 @@ CNF_GetInitStepThreshold(void)
 /* ================================================== */

 int
-CNF_GetHwTsInterface(unsigned int index, char **name, double *tx_comp, double *rx_comp)
+CNF_GetHwTsInterface(unsigned int index, CNF_HwTsInterface **iface)
 {
-  HwTs_Interface *iface;
-
  if (index >= ARR_GetSize(hwts_interfaces))
    return 0;

-  iface = ARR_GetElement(hwts_interfaces, index);
-  *name = iface->name;
-  *tx_comp = iface->tx_comp;
-  *rx_comp = iface->rx_comp;
-
+  *iface = (CNF_HwTsInterface *)ARR_GetElement(hwts_interfaces, index);
  return 1;
 }
--- a/conf.h
+++ b/conf.h
@@ -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);
@@ -119,6 +119,15 @@ extern char *CNF_GetHwclockFile(void);
 extern int CNF_GetInitSources(void);
 extern double CNF_GetInitStepThreshold(void);

-extern int CNF_GetHwTsInterface(unsigned int index, char **name, double *tx_comp, double *rx_comp);
+typedef struct {
+  char *name;
+  int minpoll;
+  int nocrossts;
+  double precision;
+  double tx_comp;
+  double rx_comp;
+} CNF_HwTsInterface;
+
+extern int CNF_GetHwTsInterface(unsigned int index, CNF_HwTsInterface **iface);

 #endif /* GOT_CONF_H */
--- a/5
+++ b/5
@@ -4,7 +4,8 @@
 # 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, 2012-2016
 #
 # =======================================================================

@@ -731,7 +732,7 @@ 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
  add_def FEAT_PHC
 fi
--- a/doc/chrony.conf.adoc
+++ b/doc/chrony.conf.adoc
@@ -1,7 +1,8 @@
 // This file is part of chrony
 //
 // Copyright (C) Richard P. Curnow  1997-2003
-// Copyright (C) Miroslav Lichvar  2009-2016
+// Copyright (C) Stephen Wadeley  2016
+// 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
@@ -67,11 +68,15 @@ options:
 Although *chronyd* will trim the rate at which it samples the server during
 normal operation, the user might want to constrain the minimum polling interval.
 This is always defined as a power of 2, so *minpoll 5* would mean that the
-polling interval cannot drop below 32 seconds. The default is 6 (64 seconds).
+polling interval cannot drop below 32 seconds. The default is 6 (64 seconds),
+the minimum is -4 (1/16th of a second), and the maximum is 24 (6 months). Note
+that intervals shorter than 6 (64 seconds) should generally not be used with
+public servers on the Internet, because it might be considered abuse.
 *maxpoll* _poll_:::
 In a similar way, the user might want to constrain the maximum polling interval.
 Again this is specified as a power of 2, *maxpoll 9* indicates that the polling
-interval must stay at or below 512 seconds. The default is 10 (1024 seconds).
+interval must stay at or below 512 seconds. The default is 10 (1024 seconds),
+the minimum is 0 (1 second), and the maximum is 24 (6 months).
 *iburst*:::
 If this option is set, the interval between the first four polls will be 2
 seconds instead of _minpoll_. This is useful to quickly get the first update of
@@ -105,7 +110,7 @@ If the user knows that round trip delays above a certain level should cause the
 measurement to be ignored, this level can be defined with the *maxdelay*
 option. For example, *maxdelay 0.3* would indicate that measurements with a
 round-trip delay of 0.3 seconds or more should be ignored. The default value is
-3 seconds.
+3 seconds and the maximum value is 1000 seconds.
 *maxdelayratio* _ratio_:::
 This option is similar to the maxdelay option above. *chronyd* keeps a record
 of the minimum round-trip delay amongst the previous measurements that it has
@@ -171,9 +176,12 @@ the interleaved mode requires the servers to keep some state for each client
 and the state might be dropped when there are too many clients (e.g.
 <<clientloglimit,*clientloglimit*>> is too small), or it might be overwritten
 by other clients that have the same IP address (e.g. computers behind NAT or
-someone sending requests with a spoofed source address). The *presend* option
-can be used to shorten the interval in which the server has to keep the state
-for this computer and be able to respond in the interleaved mode.
+someone sending requests with a spoofed source address).
+
+With longer polling intervals, it is recommended to combine the *xleave* option
+with the *presend* option in order to shorten the interval in which the server
+has to keep the state to be able to respond in the interleaved mode. The
+shorter interval also improves accuracy of the measured offset and delay.
 *polltarget* _target_:::
 Target number of measurements to use for the regression algorithm which
 *chronyd* will try to maintain by adjusting the polling interval between
@@ -397,9 +405,10 @@ refclock SOCK /var/run/chrony.ttyS0.sock
 *PHC*:::
 PTP hardware clock (PHC) driver. The parameter is the path to the device of
 the PTP clock, which for example can be synchronised by *ptp4l* from
-http://linuxptp.sourceforge.net[*linuxptp*]. PTP clocks are typically kept in
-TAI instead of UTC, so the *offset* option should be used to compensate for the
-current UTC-TAI offset. For example:
+http://linuxptp.sourceforge.net[*linuxptp*]. String *:nocrossts* can be
+appended to the path to disable use of precise cross timestamping. PTP clocks
+are typically kept in TAI instead of UTC, so the *offset* option should be used
+to compensate for the current UTC-TAI offset. For example:
 +
 ----
 refclock PHC /dev/ptp0 poll 3 dpoll -2 offset -36
@@ -1509,10 +1518,12 @@ The log files are written to the directory specified by the <<logdir,*logdir*>>
 directive. A banner is periodically written to the files to indicate the
 meanings of the columns.
 +
-*measurements*:::
+*rawmeasurements*:::
 This option logs the raw NTP measurements and related information to a file
-called _measurements.log_. An example line (which actually appears as a single
-line in the file) from the log file is shown below.
+called _measurements.log_. An entry is made for each packet received from the
+source. This can be useful when debugging a problem. An example line (which
+actually appears as a single line in the file) from the log file is shown
+below.
 +
 ----
 2016-11-09 05:40:50 203.0.113.15    N  2 111 111 1111  10 10 1.0 \
@@ -1554,6 +1565,12 @@ from the example line above):
 . Source of the local receive timestamp
  (_D_=daemon, _K_=kernel, _H_=hardware). [K]
 +
+*measurements*:::
+This option is identical to the *rawmeasurements* option, except it logs only
+valid measurements from synchronised sources, i.e. measurements which passed
+the RFC 5905 tests 1 through 7. This can be useful for producing graphs of the
+source's performance.
+
 *statistics*:::
 This option logs information about the regression processing to a file called
 _statistics.log_. An example line (which actually appears as a single line in
@@ -1813,6 +1830,15 @@ on all available interfaces.
 +
 The *hwtimestamp* directive has the following options:
 +
+*minpoll* _poll_:::
+This option specifies the minimum interval between readings of the NIC clock.
+It's defined as a power of two. It should correspond to the minimum polling
+interval of all NTP sources and the minimum expected polling interval of NTP
+clients. The default value is 0 (1 second) and the minimum value is -6 (1/64th
+of a second).
+*precision* _precision_:::
+This option specifies the assumed precision of reading of the NIC clock. The
+default value is 100e-9 (100 nanoseconds).
 *txcomp* _compensation_:::
 This option specifies the difference in seconds between the actual transmission
 time at the physical layer and the reported transmit timestamp. This value will
@@ -1822,6 +1848,9 @@ This option specifies the difference in seconds between the reported receive
 timestamp and the actual reception time at the physical layer. This value will
 be subtracted from receive timestamps obtained from the NIC. The default value
 is 0.
+*nocrossts*:::
+Some hardware can precisely cross timestamp the NIC clock with the system
+clock. This option disables the use of the cross timestamping.
 ::
 +
 Examples of the directive are:
--- a/doc/chronyc.adoc
+++ b/doc/chronyc.adoc
@@ -1,6 +1,7 @@
 // This file is part of chrony
 //
 // Copyright (C) Richard P. Curnow  1997-2003
+// Copyright (C) Stephen Wadeley  2016
 // Copyright (C) Miroslav Lichvar  2009-2016
 //
 // This program is free software; you can redistribute it and/or modify
@@ -129,15 +130,15 @@ performance. An example of the output is shown below.
 ----
 Reference ID    : CB00710F (foo.example.net)
 Stratum         : 3
-Ref time (UTC)  : Fri Feb  3 15:00:29 2012
-System time     : 0.000001501 seconds slow of NTP time
-Last offset     : -0.000001632 seconds
-RMS offset      : 0.000002360 seconds
-Frequency       : 331.898 ppm fast
-Residual freq   : 0.004 ppm
-Skew            : 0.154 ppm
-Root delay      : 0.373169 seconds
-Root dispersion : 0.024780 seconds
+Ref time (UTC)  : Fri Jan 27 09:49:17 2017
+System time     : 0.000006523 seconds slow of NTP time
+Last offset     : -0.000006747 seconds
+RMS offset      : 0.000035822 seconds
+Frequency       : 3.225 ppm slow
+Residual freq   : -0.000 ppm
+Skew            : 0.129 ppm
+Root delay      : 0.013639022 seconds
+Root dispersion : 0.001100737 seconds
 Update interval : 64.2 seconds
 Leap status     : Normal
 ----
@@ -186,9 +187,6 @@ The '`frequency`' is the rate by which the system's clock would be wrong if
 For example, a value of 1 ppm would mean that when the system's clock thinks it
 has advanced 1 second, it has actually advanced by 1.000001 seconds relative to
 true time.
-+
-As you can see in the example, the clock in the computer is not a very
-good one; it would gain about 30 seconds per day if it was not corrected!
 *Residual freq*:::
 This shows the '`residual frequency`' for the currently selected reference
 source. This reflects any difference between what the measurements from the
@@ -1132,6 +1130,10 @@ directory into which the dump files will be written. This can only be
 done in the configuration file with the <<chrony.conf.adoc#dumpdir,*dumpdir*>>
 directive.

+[[rekey]]*rekey*::
+The *rekey* command causes *chronyd* to re-read the key file specified in the
+configuration file by the <<chrony.conf.adoc#keyfile,*keyfile*>> directive.
+
 === Client commands

 [[dns]]*dns* _option_::
--- a/doc/faq.adoc
+++ b/doc/faq.adoc
@@ -79,7 +79,7 @@ rtcsync

 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 all IPv4 and IPv6 addresses.
+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?

@@ -97,7 +97,7 @@ _chrony.conf_ file. This configuration will be better because
 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 try to resolve them immediately.
+`chronyc` to force `chronyd` to try to resolve the names immediately.

 === How can I make `chronyd` more secure?

@@ -161,7 +161,7 @@ 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 8 (samples) for `polltarget`. The default values should be used
-for general servers on the Internet. With your own NTP servers or if have
+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.
@@ -195,15 +195,27 @@ server ntp.local minpoll 2 maxpoll 4 polltarget 30 maxdelaydevratio 2
 ----

 If your server supports the interleaved mode, the `xleave` option should be
-added to the `server` directive in order to receive server's more accurate
-hardware or kernel transmit timestamps. When combined with local hardware
-timestamping, a sub-microsecond accuracy may be possible. An example could be
+added to the `server` directive in order to allow the server to send the
+client more accurate hardware or kernel transmit timestamps. When combined with
+local hardware timestamping, sub-microsecond accuracy may be possible. An
+example could be

 ----
 server ntp.local minpoll 2 maxpoll 2 xleave
 hwtimestamp eth0
 ----

+=== 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'
+----
+
 === What happened to the `commandkey` and `generatecommandkey` directives?

 They were removed in version 2.2. Authentication is no longer supported in the
@@ -242,8 +254,17 @@ MS Name/IP address         Stratum Poll Reach LastRx Last sample
 === Are NTP servers specified with the `offline` option?

 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.
+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?

@@ -396,15 +417,15 @@ 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 server(s) that it thinks are online.
-When the network is connected again, it will take some time (on average half of
-the maximum 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.
+`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.

-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.
+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

--- a/examples/chrony-wait.service
+++ b/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
--- a/examples/chrony.conf.example1
+++ b/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).
--- a/examples/chrony.conf.example2
+++ b/examples/chrony.conf.example2
@@ -5,17 +5,24 @@ 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.
--- a/examples/chrony.conf.example3
+++ b/examples/chrony.conf.example3
@@ -33,42 +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.
@@ -181,13 +169,12 @@ 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

@@ -196,7 +183,7 @@ driftfile /var/lib/chrony/drift
 # clients that are sending requests too frequently, uncomment and edit
 # the following line.

-! limitrate interval 3 burst 8
+! ratelimit interval 3 burst 8

 #######################################################################
 ### REPORTING BIG CLOCK CHANGES
@@ -243,7 +230,17 @@ driftfile /var/lib/chrony/drift
 # Rate limiting can be enabled also for command packets.  (Note,
 # commands from localhost are never limited.)

-! cmdratelimit interval 1 burst 16
+! 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
@@ -274,6 +271,12 @@ 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
--- a/examples/chronyd.service
+++ b/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
 EnvironmentFile=-/etc/sysconfig/chronyd
 ExecStart=/usr/sbin/chronyd $OPTIONS
+PrivateTmp=yes
+ProtectHome=yes
+ProtectSystem=full

 [Install]
 WantedBy=multi-user.target
--- a/hwclock.c
+++ b/hwclock.c
@@ -39,9 +39,6 @@
 /* Maximum number of samples per clock */
 #define MAX_SAMPLES 16

-/* Minimum interval between samples (in seconds) */
-#define MIN_SAMPLE_SEPARATION 1.0
-
 struct HCL_Instance_Record {
  /* HW and local reference timestamp */
  struct timespec hw_ref;
@@ -58,6 +55,9 @@ struct HCL_Instance_Record {
  /* 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;

@@ -86,7 +86,7 @@ handle_slew(struct timespec *raw, struct timespec *cooked, double dfreq,
 /* ================================================== */

 HCL_Instance
-HCL_CreateInstance(void)
+HCL_CreateInstance(double min_separation)
 {
  HCL_Instance clock;

@@ -95,6 +95,7 @@ HCL_CreateInstance(void)
  clock->y_data[MAX_SAMPLES - 1] = 0.0;
  clock->n_samples = 0;
  clock->valid_coefs = 0;
+  clock->min_separation = min_separation;

  LCL_AddParameterChangeHandler(handle_slew, clock);

@@ -115,7 +116,7 @@ int
 HCL_NeedsNewSample(HCL_Instance clock, struct timespec *now)
 {
  if (!clock->n_samples ||
-      fabs(UTI_DiffTimespecsToDouble(now, &clock->local_ref)) >= MIN_SAMPLE_SEPARATION)
+      fabs(UTI_DiffTimespecsToDouble(now, &clock->local_ref)) >= clock->min_separation)
    return 1;

  return 0;
@@ -140,7 +141,7 @@ HCL_AccumulateSample(HCL_Instance clock, struct timespec *hw_ts,
    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 < MIN_SAMPLE_SEPARATION / 2.0) {
+    if (hw_delta <= 0.0 || local_delta < clock->min_separation / 2.0) {
      clock->n_samples = 0;
      DEBUG_LOG(LOGF_HwClocks, "HW clock reset interval=%f", local_delta);
    }
--- a/hwclock.h
+++ b/hwclock.h
@@ -29,7 +29,7 @@
 typedef struct HCL_Instance_Record *HCL_Instance;

 /* Create a new HW clock instance */
-extern HCL_Instance HCL_CreateInstance(void);
+extern HCL_Instance HCL_CreateInstance(double min_separation);

 /* Destroy a HW clock instance */
 extern void HCL_DestroyInstance(HCL_Instance clock);
--- a/local.c
+++ b/local.c
@@ -144,6 +144,8 @@ calculate_sys_precision(void)
    best *= 2;
  }

+  assert(precision_log >= -30);
+
  DEBUG_LOG(LOGF_Local, "Clock precision %.9f (%d)", precision_quantum, precision_log);
 }

--- a/main.c
+++ b/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  2012-2016
 * 
 * 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
@@ -325,7 +325,8 @@ 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
--- a/ntp_core.c
+++ b/ntp_core.c
@@ -3,7 +3,7 @@

 **********************************************************************
 * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2009-2016
+ * 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
@@ -49,6 +49,7 @@
 /* ================================================== */

 static LOG_FileID logfileid;
+static int log_raw_measurements;

 /* ================================================== */
 /* Enumeration used for remembering the operating mode of one of the
@@ -205,7 +206,8 @@ static ARR_Instance broadcasts;

 /* Spacing required between samples for any two servers/peers (to
   minimise risk of network collisions) (in seconds) */
-#define SAMPLING_SEPARATION 0.2
+#define MIN_SAMPLING_SEPARATION 0.02
+#define MAX_SAMPLING_SEPARATION 0.2

 /* Randomness added to spacing between samples for one server/peer */
 #define SAMPLING_RANDOMNESS 0.02
@@ -243,8 +245,14 @@ static ARR_Instance broadcasts;
 /* Maximum acceptable delay in transmission for timestamp correction */
 #define MAX_TX_DELAY 1.0

+/* Maximum allowed values of maxdelay parameters */
+#define MAX_MAXDELAY 1.0e3
+#define MAX_MAXDELAYRATIO 1.0e6
+#define MAX_MAXDELAYDEVRATIO 1.0e6
+
 /* Minimum and maximum allowed poll interval */
-#define MIN_POLL 0
+#define MIN_MINPOLL -4
+#define MIN_MAXPOLL 0
 #define MAX_POLL 24

 /* Kiss-o'-Death codes */
@@ -273,6 +281,7 @@ static const char tss_chars[3] = {'D', 'K', 'H'};

 static void transmit_timeout(void *arg);
 static double get_transmit_delay(NCR_Instance inst, int on_tx, double last_tx);
+static double get_separation(int poll);

 /* ================================================== */

@@ -345,7 +354,7 @@ NCR_Initialise(void)
  do_size_checks();
  do_time_checks();

-  logfileid = CNF_GetLogMeasurements() ? LOG_FileOpen("measurements",
+  logfileid = CNF_GetLogMeasurements(&log_raw_measurements) ? LOG_FileOpen("measurements",
      "   Date (UTC) Time     IP Address   L St 123 567 ABCD  LP RP Score    Offset  Peer del. Peer disp.  Root del. Root disp. Refid     MTxRx")
    : -1;

@@ -393,7 +402,7 @@ restart_timeout(NCR_Instance inst, double delay)
  SCH_RemoveTimeout(inst->tx_timeout_id);

  /* Start new timer for transmission */
-  inst->tx_timeout_id = SCH_AddTimeoutInClass(delay, SAMPLING_SEPARATION,
+  inst->tx_timeout_id = SCH_AddTimeoutInClass(delay, get_separation(inst->local_poll),
                                              SAMPLING_RANDOMNESS,
                                              SCH_NtpSamplingClass,
                                              transmit_timeout, (void *)inst);
@@ -474,6 +483,7 @@ NCR_GetInstance(NTP_Remote_Address *remote_addr, NTP_Source_Type type, SourcePar

  result->remote_addr = *remote_addr;
  result->local_addr.ip_addr.family = IPADDR_UNSPEC;
+  result->local_addr.if_index = INVALID_IF_INDEX;

  switch (type) {
    case NTP_SERVER:
@@ -492,12 +502,12 @@ NCR_GetInstance(NTP_Remote_Address *remote_addr, NTP_Source_Type type, SourcePar
  result->interleaved = params->interleaved;

  result->minpoll = params->minpoll;
-  if (result->minpoll < MIN_POLL)
+  if (result->minpoll < MIN_MINPOLL)
    result->minpoll = SRC_DEFAULT_MINPOLL;
  else if (result->minpoll > MAX_POLL)
    result->minpoll = MAX_POLL;
  result->maxpoll = params->maxpoll;
-  if (result->maxpoll < MIN_POLL)
+  if (result->maxpoll < MIN_MAXPOLL)
    result->maxpoll = SRC_DEFAULT_MAXPOLL;
  else if (result->maxpoll > MAX_POLL)
    result->maxpoll = MAX_POLL;
@@ -513,9 +523,9 @@ NCR_GetInstance(NTP_Remote_Address *remote_addr, NTP_Source_Type type, SourcePar
  if (result->presend_minpoll <= MAX_POLL && result->mode != MODE_CLIENT)
    result->presend_minpoll = MAX_POLL + 1;

-  result->max_delay = params->max_delay;
-  result->max_delay_ratio = params->max_delay_ratio;
-  result->max_delay_dev_ratio = params->max_delay_dev_ratio;
+  result->max_delay = CLAMP(0.0, params->max_delay, MAX_MAXDELAY);
+  result->max_delay_ratio = CLAMP(0.0, params->max_delay_ratio, MAX_MAXDELAYRATIO);
+  result->max_delay_dev_ratio = CLAMP(0.0, params->max_delay_dev_ratio, MAX_MAXDELAYDEVRATIO);
  result->offset_correction = params->offset;
  result->auto_offline = params->auto_offline;
  result->poll_target = params->poll_target;
@@ -648,6 +658,7 @@ NCR_ResetPoll(NCR_Instance instance)
 void
 NCR_ChangeRemoteAddress(NCR_Instance inst, NTP_Remote_Address *remote_addr)
 {
+  memset(&inst->report, 0, sizeof (inst->report));
  NCR_ResetInstance(inst);
  inst->remote_addr = *remote_addr;

@@ -656,6 +667,7 @@ NCR_ChangeRemoteAddress(NCR_Instance inst, NTP_Remote_Address *remote_addr)
  else {
    NIO_CloseServerSocket(inst->local_addr.sock_fd);
    inst->local_addr.ip_addr.family = IPADDR_UNSPEC;
+    inst->local_addr.if_index = INVALID_IF_INDEX;
    inst->local_addr.sock_fd = NIO_OpenServerSocket(remote_addr);
  }

@@ -759,7 +771,7 @@ get_transmit_delay(NCR_Instance inst, int on_tx, double last_tx)
             approx the poll interval away */
          poll_to_use = inst->local_poll;

-          delay_time = (double) (1UL<<poll_to_use);
+          delay_time = UTI_Log2ToDouble(poll_to_use);
          if (inst->presend_done)
            delay_time = WARM_UP_DELAY;

@@ -777,7 +789,7 @@ get_transmit_delay(NCR_Instance inst, int on_tx, double last_tx)
          if (poll_to_use < inst->minpoll)
            poll_to_use = inst->minpoll;

-          delay_time = (double) (1UL<<poll_to_use);
+          delay_time = UTI_Log2ToDouble(poll_to_use);

          /* If the remote stratum is higher than ours, try to lock on the
             peer's polling to minimize our response time by slightly extending
@@ -816,6 +828,21 @@ get_transmit_delay(NCR_Instance inst, int on_tx, double last_tx)
  return delay_time;
 }

+/* ================================================== */
+/* Calculate sampling separation for given polling interval */
+
+static double
+get_separation(int poll)
+{
+  double separation;
+
+  /* Allow up to 8 sources using the same short interval to not be limited
+     by the separation */
+  separation = UTI_Log2ToDouble(poll - 3);
+
+  return CLAMP(MIN_SAMPLING_SEPARATION, separation, MAX_SAMPLING_SEPARATION);
+}
+
 /* ================================================== */
 /* Timeout handler for closing the client socket when no acceptable
   reply can be received from the server */
@@ -951,57 +978,63 @@ transmit_packet(NTP_Mode my_mode, /* The mode this machine wants to be */
     frequency all along */
  UTI_TimespecToNtp64(&local_receive, &message.receive_ts, &ts_fuzz);

-  /* Prepare random bits which will be added to the transmit timestamp. */
-  UTI_GetNtp64Fuzz(&ts_fuzz, precision);
+  do {
+    /* Prepare random bits which will be added to the transmit timestamp */
+    UTI_GetNtp64Fuzz(&ts_fuzz, precision);

-  /* Transmit - this our local time right now!  Also, we might need to
-     store this for our own use later, next time we receive a message
-     from the source we're sending to now. */
-  LCL_ReadCookedTime(&local_transmit, &local_transmit_err);
+    /* Transmit - this our local time right now!  Also, we might need to
+       store this for our own use later, next time we receive a message
+       from the source we're sending to now. */
+    LCL_ReadCookedTime(&local_transmit, &local_transmit_err);

-  if (smooth_time)
-    UTI_AddDoubleToTimespec(&local_transmit, smooth_offset, &local_transmit);
+    if (smooth_time)
+      UTI_AddDoubleToTimespec(&local_transmit, smooth_offset, &local_transmit);

-  length = NTP_NORMAL_PACKET_LENGTH;
+    length = NTP_NORMAL_PACKET_LENGTH;

-  /* Authenticate the packet if needed */
+    /* Authenticate the packet */

-  if (auth_mode == AUTH_SYMMETRIC || auth_mode == AUTH_MSSNTP) {
-    /* Pre-compensate the transmit time by approx. how long it will
-       take to generate the authentication data. */
-    local_transmit.tv_nsec += auth_mode == AUTH_SYMMETRIC ?
-                              KEY_GetAuthDelay(key_id) : NSD_GetAuthDelay(key_id);
-    UTI_NormaliseTimespec(&local_transmit);
-    UTI_TimespecToNtp64(interleaved ? &local_tx->ts : &local_transmit,
-                        &message.transmit_ts, &ts_fuzz);
+    if (auth_mode == AUTH_SYMMETRIC || auth_mode == AUTH_MSSNTP) {
+      /* Pre-compensate the transmit time by approximately how long it will
+         take to generate the authentication data */
+      local_transmit.tv_nsec += auth_mode == AUTH_SYMMETRIC ?
+                                KEY_GetAuthDelay(key_id) : NSD_GetAuthDelay(key_id);
+      UTI_NormaliseTimespec(&local_transmit);
+      UTI_TimespecToNtp64(interleaved ? &local_tx->ts : &local_transmit,
+                          &message.transmit_ts, &ts_fuzz);

-    if (auth_mode == AUTH_SYMMETRIC) {
-      auth_len = KEY_GenerateAuth(key_id, (unsigned char *) &message,
-                                  offsetof(NTP_Packet, auth_keyid),
-                                  (unsigned char *)&message.auth_data,
-                                  sizeof (message.auth_data));
-      if (!auth_len) {
-        DEBUG_LOG(LOGF_NtpCore, "Could not generate auth data with key %"PRIu32, key_id);
-        return 0;
+      if (auth_mode == AUTH_SYMMETRIC) {
+        auth_len = KEY_GenerateAuth(key_id, (unsigned char *) &message,
+                                    offsetof(NTP_Packet, auth_keyid),
+                                    (unsigned char *)&message.auth_data,
+                                    sizeof (message.auth_data));
+        if (!auth_len) {
+          DEBUG_LOG(LOGF_NtpCore, "Could not generate auth data with key %"PRIu32, key_id);
+          return 0;
+        }
+
+        message.auth_keyid = htonl(key_id);
+        mac_len = sizeof (message.auth_keyid) + auth_len;
+
+        /* Truncate MACs in NTPv4 packets to allow deterministic parsing
+           of extension fields (RFC 7822) */
+        if (version == 4 && mac_len > NTP_MAX_V4_MAC_LENGTH)
+          mac_len = NTP_MAX_V4_MAC_LENGTH;
+
+        length += mac_len;
+      } else if (auth_mode == AUTH_MSSNTP) {
+        /* MS-SNTP packets are signed (asynchronously) by ntp_signd */
+        return NSD_SignAndSendPacket(key_id, &message, where_to, from, length);
      }
-
-      message.auth_keyid = htonl(key_id);
-      mac_len = sizeof (message.auth_keyid) + auth_len;
-
-      /* Truncate MACs in NTPv4 packets to allow deterministic parsing
-         of extension fields (RFC 7822) */
-      if (version == 4 && mac_len > NTP_MAX_V4_MAC_LENGTH)
-        mac_len = NTP_MAX_V4_MAC_LENGTH;
-
-      length += mac_len;
-    } else if (auth_mode == AUTH_MSSNTP) {
-      /* MS-SNTP packets are signed (asynchronously) by ntp_signd */
-      return NSD_SignAndSendPacket(key_id, &message, where_to, from, length);
+    } else {
+      UTI_TimespecToNtp64(interleaved ? &local_tx->ts : &local_transmit,
+                          &message.transmit_ts, &ts_fuzz);
    }
-  } else {
-    UTI_TimespecToNtp64(interleaved ? &local_tx->ts : &local_transmit,
-                        &message.transmit_ts, &ts_fuzz);
-  }
+
+    /* Avoid sending messages with non-zero transmit timestamp equal to the
+       receive timestamp to allow reliable detection of the interleaved mode */
+  } while (!UTI_CompareNtp64(&message.transmit_ts, &message.receive_ts) &&
+           !UTI_IsZeroNtp64(&message.transmit_ts));

  ret = NIO_SendPacket(&message, where_to, from, length, local_tx != NULL);

@@ -1064,6 +1097,7 @@ transmit_timeout(void *arg)

  /* Don't require the packet to be sent from the same address as before */
  local_addr.ip_addr.family = IPADDR_UNSPEC;
+  local_addr.if_index = INVALID_IF_INDEX;
  local_addr.sock_fd = inst->local_addr.sock_fd;

  /* Check whether we need to 'warm up' the link to the other end by
@@ -1445,7 +1479,7 @@ receive_packet(NCR_Instance inst, NTP_Local_Address *local_addr,
       processing time is sane, and in the interleaved symmetric mode that
       the delay is not longer than half of the remote polling interval to
       detect missed packets */
-    testA = delay - dispersion <= inst->max_delay &&
+    testA = delay - dispersion <= inst->max_delay && precision <= inst->max_delay &&
            !(inst->mode == MODE_CLIENT && server_interval > MAX_SERVER_INTERVAL) &&
            !(inst->mode == MODE_ACTIVE && interleaved_packet &&
              delay > UTI_Log2ToDouble(message->poll - 1));
@@ -1597,8 +1631,9 @@ receive_packet(NCR_Instance inst, NTP_Local_Address *local_addr,
       server and the socket can be closed */
    close_client_socket(inst);

-    /* Update the local address */
+    /* Update the local address and interface */
    inst->local_addr.ip_addr = local_addr->ip_addr;
+    inst->local_addr.if_index = local_addr->if_index;

    /* And now, requeue the timer */
    if (inst->opmode != MD_OFFLINE) {
@@ -1610,7 +1645,7 @@ receive_packet(NCR_Instance inst, NTP_Local_Address *local_addr,
            UTI_IPToString(&inst->remote_addr.ip_addr));

        /* Back off for a while and stop ongoing burst */
-        delay_time += 4 * (1UL << inst->minpoll);
+        delay_time += 4 * UTI_Log2ToDouble(inst->local_poll);

        if (inst->opmode == MD_BURST_WAS_OFFLINE || inst->opmode == MD_BURST_WAS_ONLINE) {
          inst->burst_good_samples_to_go = 0;
@@ -1653,7 +1688,7 @@ receive_packet(NCR_Instance inst, NTP_Local_Address *local_addr,
  }

  /* Do measurement logging */
-  if (logfileid != -1) {
+  if (logfileid != -1 && (log_raw_measurements || synced_packet)) {
    LOG_FileWrite(logfileid, "%s %-15s %1c %2d %1d%1d%1d %1d%1d%1d %1d%1d%1d%d  %2d %2d %4.2f %10.3e %10.3e %10.3e %10.3e %10.3e %08"PRIX32" %1d%1c %1c %1c",
            UTI_TimeToLogForm(sample_time.tv_sec),
            UTI_IPToString(&inst->remote_addr.ip_addr),
@@ -1909,10 +1944,7 @@ NCR_ProcessRxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_a
                  !UTI_CompareNtp64(&message->originate_ts, local_ntp_rx);

    if (interleaved) {
-      if (!UTI_IsZeroNtp64(local_ntp_tx))
-        UTI_Ntp64ToTimespec(local_ntp_tx, &local_tx.ts);
-      else
-        interleaved = 0;
+      UTI_Ntp64ToTimespec(local_ntp_tx, &local_tx.ts);
      tx_ts = &local_tx;
    } else {
      UTI_ZeroNtp64(local_ntp_tx);
@@ -2005,10 +2037,10 @@ NCR_ProcessTxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_a
  if (log_index < 0)
    return;

-  CLG_GetNtpTimestamps(log_index, &local_ntp_rx, &local_ntp_tx);
+  if (SMT_IsEnabled() && NTP_LVM_TO_MODE(message->lvm) == MODE_SERVER)
+    UTI_AddDoubleToTimespec(&tx_ts->ts, SMT_GetOffset(&tx_ts->ts), &tx_ts->ts);

-  if (UTI_IsZeroNtp64(local_ntp_tx))
-    return;
+  CLG_GetNtpTimestamps(log_index, &local_ntp_rx, &local_ntp_tx);

  UTI_Ntp64ToTimespec(local_ntp_tx, &local_tx.ts);
  update_tx_timestamp(&local_tx, tx_ts, local_ntp_rx, NULL, message);
@@ -2080,7 +2112,7 @@ NCR_TakeSourceOffline(NCR_Instance inst)
 void
 NCR_ModifyMinpoll(NCR_Instance inst, int new_minpoll)
 {
-  if (new_minpoll < MIN_POLL || new_minpoll > MAX_POLL)
+  if (new_minpoll < MIN_MINPOLL || new_minpoll > MAX_POLL)
    return;
  inst->minpoll = new_minpoll;
  LOG(LOGS_INFO, LOGF_NtpCore, "Source %s new minpoll %d", UTI_IPToString(&inst->remote_addr.ip_addr), new_minpoll);
@@ -2093,7 +2125,7 @@ NCR_ModifyMinpoll(NCR_Instance inst, int new_minpoll)
 void
 NCR_ModifyMaxpoll(NCR_Instance inst, int new_maxpoll)
 {
-  if (new_maxpoll < MIN_POLL || new_maxpoll > MAX_POLL)
+  if (new_maxpoll < MIN_MAXPOLL || new_maxpoll > MAX_POLL)
    return;
  inst->maxpoll = new_maxpoll;
  LOG(LOGS_INFO, LOGF_NtpCore, "Source %s new maxpoll %d", UTI_IPToString(&inst->remote_addr.ip_addr), new_maxpoll);
@@ -2106,9 +2138,9 @@ NCR_ModifyMaxpoll(NCR_Instance inst, int new_maxpoll)
 void
 NCR_ModifyMaxdelay(NCR_Instance inst, double new_max_delay)
 {
-  inst->max_delay = new_max_delay;
+  inst->max_delay = CLAMP(0.0, new_max_delay, MAX_MAXDELAY);
  LOG(LOGS_INFO, LOGF_NtpCore, "Source %s new max delay %f",
-      UTI_IPToString(&inst->remote_addr.ip_addr), new_max_delay);
+      UTI_IPToString(&inst->remote_addr.ip_addr), inst->max_delay);
 }

 /* ================================================== */
@@ -2116,9 +2148,9 @@ NCR_ModifyMaxdelay(NCR_Instance inst, double new_max_delay)
 void
 NCR_ModifyMaxdelayratio(NCR_Instance inst, double new_max_delay_ratio)
 {
-  inst->max_delay_ratio = new_max_delay_ratio;
+  inst->max_delay_ratio = CLAMP(0.0, new_max_delay_ratio, MAX_MAXDELAYRATIO);
  LOG(LOGS_INFO, LOGF_NtpCore, "Source %s new max delay ratio %f",
-      UTI_IPToString(&inst->remote_addr.ip_addr), new_max_delay_ratio);
+      UTI_IPToString(&inst->remote_addr.ip_addr), inst->max_delay_ratio);
 }

 /* ================================================== */
@@ -2126,9 +2158,9 @@ NCR_ModifyMaxdelayratio(NCR_Instance inst, double new_max_delay_ratio)
 void
 NCR_ModifyMaxdelaydevratio(NCR_Instance inst, double new_max_delay_dev_ratio)
 {
-  inst->max_delay_dev_ratio = new_max_delay_dev_ratio;
+  inst->max_delay_dev_ratio = CLAMP(0.0, new_max_delay_dev_ratio, MAX_MAXDELAYDEVRATIO);
  LOG(LOGS_INFO, LOGF_NtpCore, "Source %s new max delay dev ratio %f",
-      UTI_IPToString(&inst->remote_addr.ip_addr), new_max_delay_dev_ratio);
+      UTI_IPToString(&inst->remote_addr.ip_addr), inst->max_delay_dev_ratio);
 }

 /* ================================================== */
@@ -2332,20 +2364,21 @@ broadcast_timeout(void *arg)
  BroadcastDestination *destination;
  NTP_int64 orig_ts;
  NTP_Local_Timestamp recv_ts;
+  int poll;

  destination = ARR_GetElement(broadcasts, (long)arg);
+  poll = log(destination->interval) / log(2.0) + 0.5;

  UTI_ZeroNtp64(&orig_ts);
  UTI_ZeroTimespec(&recv_ts.ts);
  recv_ts.source = NTP_TS_DAEMON;
  recv_ts.err = 0.0;

-  transmit_packet(MODE_BROADCAST, 0, log(destination->interval) / log(2.0) + 0.5,
-                  NTP_VERSION, 0, 0, &orig_ts, &orig_ts, &recv_ts, NULL, NULL, NULL,
-                  &destination->addr, &destination->local_addr);
+  transmit_packet(MODE_BROADCAST, 0, poll, NTP_VERSION, 0, 0, &orig_ts, &orig_ts, &recv_ts,
+                  NULL, NULL, NULL, &destination->addr, &destination->local_addr);

  /* Requeue timeout.  We don't care if interval drifts gradually. */
-  SCH_AddTimeoutInClass(destination->interval, SAMPLING_SEPARATION, SAMPLING_RANDOMNESS,
+  SCH_AddTimeoutInClass(destination->interval, get_separation(poll), SAMPLING_RANDOMNESS,
                        SCH_NtpBroadcastClass, broadcast_timeout, arg);
 }

@@ -2361,10 +2394,11 @@ NCR_AddBroadcastDestination(IPAddr *addr, unsigned short port, int interval)
  destination->addr.ip_addr = *addr;
  destination->addr.port = port;
  destination->local_addr.ip_addr.family = IPADDR_UNSPEC;
+  destination->local_addr.if_index = INVALID_IF_INDEX;
  destination->local_addr.sock_fd = NIO_OpenServerSocket(&destination->addr);
-  destination->interval = CLAMP(1 << MIN_POLL, interval, 1 << MAX_POLL);
+  destination->interval = CLAMP(1, interval, 1 << MAX_POLL);

-  SCH_AddTimeoutInClass(destination->interval, SAMPLING_SEPARATION, SAMPLING_RANDOMNESS,
+  SCH_AddTimeoutInClass(destination->interval, MAX_SAMPLING_SEPARATION, SAMPLING_RANDOMNESS,
                        SCH_NtpBroadcastClass, broadcast_timeout,
                        (void *)(long)(ARR_GetSize(broadcasts) - 1));
 }
--- a/ntp_io.c
+++ b/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
 * 
 * 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
@@ -365,9 +365,8 @@ NIO_Initialise(int family)
  NIO_Linux_Initialise();
 #else
  if (1) {
-    double tx_comp, rx_comp;
-    char *name;
-    if (CNF_GetHwTsInterface(0, &name, &tx_comp, &rx_comp))
+    CNF_HwTsInterface *conf_iface;
+    if (CNF_GetHwTsInterface(0, &conf_iface))
      LOG_FATAL(LOGF_NtpIO, "HW timestamping not supported");
  }
 #endif
@@ -579,7 +578,6 @@ process_message(struct msghdr *hdr, int length, int sock_fd)
  NTP_Local_Timestamp local_ts;
  struct timespec sched_ts;
  struct cmsghdr *cmsg;
-  int if_index;

  SCH_GetLastEventTime(&local_ts.ts, &local_ts.err, NULL);
  local_ts.source = NTP_TS_DAEMON;
@@ -599,8 +597,8 @@ process_message(struct msghdr *hdr, int length, int sock_fd)
  }

  local_addr.ip_addr.family = IPADDR_UNSPEC;
+  local_addr.if_index = INVALID_IF_INDEX;
  local_addr.sock_fd = sock_fd;
-  if_index = -1;

  if (hdr->msg_flags & MSG_TRUNC) {
    DEBUG_LOG(LOGF_NtpIO, "Received truncated message from %s:%d",
@@ -621,7 +619,7 @@ process_message(struct msghdr *hdr, int length, int sock_fd)
      memcpy(&ipi, CMSG_DATA(cmsg), sizeof(ipi));
      local_addr.ip_addr.addr.in4 = ntohl(ipi.ipi_addr.s_addr);
      local_addr.ip_addr.family = IPADDR_INET4;
-      if_index = ipi.ipi_ifindex;
+      local_addr.if_index = ipi.ipi_ifindex;
    }
 #endif

@@ -633,7 +631,7 @@ process_message(struct msghdr *hdr, int length, int sock_fd)
      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;
-      if_index = ipi.ipi6_ifindex;
+      local_addr.if_index = ipi.ipi6_ifindex;
    }
 #endif

@@ -661,14 +659,13 @@ process_message(struct msghdr *hdr, int length, int sock_fd)
  }

 #ifdef HAVE_LINUX_TIMESTAMPING
-  if (NIO_Linux_ProcessMessage(&remote_addr, &local_addr, &local_ts,
-                               hdr, length, sock_fd, if_index))
+  if (NIO_Linux_ProcessMessage(&remote_addr, &local_addr, &local_ts, hdr, length))
    return;
 #endif

  DEBUG_LOG(LOGF_NtpIO, "Received %d bytes from %s:%d to %s fd=%d if=%d tss=%d delay=%.9f",
            length, UTI_IPToString(&remote_addr.ip_addr), remote_addr.port,
-            UTI_IPToString(&local_addr.ip_addr), local_addr.sock_fd, if_index,
+            UTI_IPToString(&local_addr.ip_addr), local_addr.sock_fd, local_addr.if_index,
            local_ts.source, UTI_DiffTimespecsToDouble(&sched_ts, &local_ts.ts));

  /* Just ignore the packet if it's not of a recognized length */
--- a/ntp_io_linux.c
+++ b/ntp_io_linux.c
@@ -2,7 +2,7 @@
  chronyd/chronyc - Programs for keeping computer clocks accurate.

 **********************************************************************
- * Copyright (C) Miroslav Lichvar  2016
+ * Copyright (C) Miroslav Lichvar  2016-2017
 * 
 * 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
@@ -61,11 +61,15 @@ 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;
@@ -75,6 +79,9 @@ struct Interface {
 /* 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

@@ -91,19 +98,18 @@ static int permanent_ts_options;
 /* ================================================== */

 static int
-add_interface(const char *name, double tx_comp, double rx_comp)
+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_index, phc_fd;
+  int sock_fd, if_index, phc_fd, req_hwts_flags;
  unsigned int i;
  struct Interface *iface;
-  char phc_path[64];

  /* Check if the interface was not already added */
  for (i = 0; i < ARR_GetSize(interfaces); i++) {
-    if (!strcmp(name, ((struct Interface *)ARR_GetElement(interfaces, i))->name))
+    if (!strcmp(conf_iface->name, ((struct Interface *)ARR_GetElement(interfaces, i))->name))
      return 1;
  }

@@ -114,7 +120,8 @@ add_interface(const char *name, double tx_comp, double rx_comp)
  memset(&req, 0, sizeof (req));
  memset(&ts_info, 0, sizeof (ts_info));

-  if (snprintf(req.ifr_name, sizeof (req.ifr_name), "%s", name) >= sizeof (req.ifr_name)) {
+  if (snprintf(req.ifr_name, sizeof (req.ifr_name), "%s", conf_iface->name) >=
+      sizeof (req.ifr_name)) {
    close(sock_fd);
    return 0;
  }
@@ -136,6 +143,14 @@ add_interface(const char *name, double tx_comp, double rx_comp)
    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(LOGF_NtpIOLinux, "HW timestamping not supported on %s", req.ifr_name);
+    close(sock_fd);
+    return 0;
+  }
+
  ts_config.flags = 0;
  ts_config.tx_type = HWTSTAMP_TX_ON;
  ts_config.rx_filter = HWTSTAMP_FILTER_ALL;
@@ -148,36 +163,31 @@ add_interface(const char *name, double tx_comp, double rx_comp)
  }

  close(sock_fd);
-  phc_index = ts_info.phc_index;

-  if (snprintf(phc_path, sizeof (phc_path), "/dev/ptp%d", phc_index) >= sizeof (phc_path))
+  phc_fd = SYS_Linux_OpenPHC(NULL, ts_info.phc_index);
+  if (phc_fd < 0)
    return 0;

-  phc_fd = open(phc_path, O_RDONLY);
-  if (phc_fd < 0) {
-    LOG(LOGS_ERR, LOGF_NtpIOLinux, "Could not open %s : %s", phc_path, strerror(errno));
-    return 0;
-  }
-
-  UTI_FdSetCloexec(phc_fd);
-
  iface = ARR_GetNewElement(interfaces);

-  snprintf(iface->name, sizeof (iface->name), "%s", name);
+  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->tx_comp = tx_comp;
-  iface->rx_comp = rx_comp;
+  iface->precision = conf_iface->precision;
+  iface->tx_comp = conf_iface->tx_comp;
+  iface->rx_comp = conf_iface->rx_comp;

-  iface->clock = HCL_CreateInstance();
+  iface->clock = HCL_CreateInstance(UTI_Log2ToDouble(MAX(conf_iface->minpoll, MIN_PHC_POLL)));

-  DEBUG_LOG(LOGF_NtpIOLinux, "Enabled HW timestamping on %s", name);
+  LOG(LOGS_INFO, LOGF_NtpIOLinux, "Enabled HW timestamping on %s", iface->name);

  return 1;
 }
@@ -185,18 +195,22 @@ add_interface(const char *name, double tx_comp, double rx_comp)
 /* ================================================== */

 static int
-add_all_interfaces(double tx_comp, double rx_comp)
+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(LOGF_NtpIOLinux, "getifaddrs() failed : %s", strerror(errno));
    return 0;
  }

  for (r = 0, ifa = ifaddr; ifa; ifa = ifa->ifa_next) {
-    if (add_interface(ifa->ifa_name, tx_comp, rx_comp))
+    conf_iface.name = ifa->ifa_name;
+    if (add_interface(&conf_iface))
      r = 1;
  }
  
@@ -242,8 +256,7 @@ update_interface_speed(struct Interface *iface)
 void
 NIO_Linux_Initialise(void)
 {
-  double tx_comp, rx_comp;
-  char *name;
+  CNF_HwTsInterface *conf_iface;
  unsigned int i;
  int hwts;

@@ -252,18 +265,18 @@ NIO_Linux_Initialise(void)
  /* 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, &name, &tx_comp, &rx_comp); i++) {
-    if (!strcmp("*", name))
+  for (i = hwts = 0; CNF_GetHwTsInterface(i, &conf_iface); i++) {
+    if (!strcmp("*", conf_iface->name))
      continue;
-    if (!add_interface(name, tx_comp, rx_comp))
-      LOG_FATAL(LOGF_NtpIO, "Could not enable HW timestamping on %s", name);
+    if (!add_interface(conf_iface))
+      LOG_FATAL(LOGF_NtpIO, "Could not enable HW timestamping on %s", conf_iface->name);
    hwts = 1;
  }

-  for (i = 0; CNF_GetHwTsInterface(i, &name, &tx_comp, &rx_comp); i++) {
-    if (strcmp("*", name))
+  for (i = 0; CNF_GetHwTsInterface(i, &conf_iface); i++) {
+    if (strcmp("*", conf_iface->name))
      continue;
-    if (add_all_interfaces(tx_comp, rx_comp))
+    if (add_all_interfaces(conf_iface))
      hwts = 1;
    break;
  }
@@ -337,68 +350,6 @@ NIO_Linux_SetTimestampSocketOptions(int sock_fd, int client_only, int *events)

 /* ================================================== */

-static int
-get_phc_sample(int phc_fd, struct timespec *phc_ts, struct timespec *local_ts, double *p_delay)
-{
-  struct ptp_sys_offset sys_off;
-  struct timespec ts1, ts2, ts3, phc_tss[PHC_READINGS], sys_tss[PHC_READINGS];
-  double min_delay = 0.0, delays[PHC_READINGS], phc_sum, local_sum, local_prec;
-  int i, n;
-
-  /* Silence valgrind */
-  memset(&sys_off, 0, sizeof (sys_off));
-
-  sys_off.n_samples = PHC_READINGS;
-
-  if (ioctl(phc_fd, PTP_SYS_OFFSET, &sys_off)) {
-    DEBUG_LOG(LOGF_NtpIOLinux, "ioctl(%s) failed : %s", "PTP_SYS_OFFSET", strerror(errno));
-    return 0;
-  }
-
-  for (i = 0; i < PHC_READINGS; i++) {
-    ts1.tv_sec = sys_off.ts[i * 2].sec;
-    ts1.tv_nsec = sys_off.ts[i * 2].nsec;
-    ts2.tv_sec = sys_off.ts[i * 2 + 1].sec;
-    ts2.tv_nsec = sys_off.ts[i * 2 + 1].nsec;
-    ts3.tv_sec = sys_off.ts[i * 2 + 2].sec;
-    ts3.tv_nsec = sys_off.ts[i * 2 + 2].nsec;
-
-    sys_tss[i] = ts1;
-    phc_tss[i] = ts2;
-    delays[i] = UTI_DiffTimespecsToDouble(&ts3, &ts1);
-
-    if (delays[i] <= 0.0)
-      /* Step in the middle of a PHC reading? */
-      return 0;
-
-    if (!i || delays[i] < min_delay)
-      min_delay = delays[i];
-  }
-
-  local_prec = LCL_GetSysPrecisionAsQuantum();
-
-  /* Combine best readings */
-  for (i = n = 0, phc_sum = local_sum = 0.0; i < PHC_READINGS; i++) {
-    if (delays[i] > min_delay + local_prec)
-      continue;
-
-    phc_sum += UTI_DiffTimespecsToDouble(&phc_tss[i], &phc_tss[0]);
-    local_sum += UTI_DiffTimespecsToDouble(&sys_tss[i], &sys_tss[0]) + delays[i] / 2.0;
-    n++;
-  }
-
-  assert(n);
-
-  UTI_AddDoubleToTimespec(&phc_tss[0], phc_sum / n, phc_ts);
-  UTI_AddDoubleToTimespec(&sys_tss[0], local_sum / n, &ts1);
-  LCL_CookTime(&ts1, local_ts, NULL);
-  *p_delay = min_delay;
-
-  return 1;
-}
-
-/* ================================================== */
-
 static struct Interface *
 get_interface(int if_index)
 {
@@ -422,16 +373,17 @@ static void
 process_hw_timestamp(struct Interface *iface, struct timespec *hw_ts,
                     NTP_Local_Timestamp *local_ts, int rx_ntp_length, int family)
 {
-  struct timespec sample_phc_ts, sample_local_ts, ts;
-  double sample_delay, rx_correction, ts_delay, err;
+  struct timespec sample_phc_ts, sample_sys_ts, sample_local_ts, ts;
+  double rx_correction, ts_delay, err;
  int l2_length;

  if (HCL_NeedsNewSample(iface->clock, &local_ts->ts)) {
-    if (!get_phc_sample(iface->phc_fd, &sample_phc_ts, &sample_local_ts, &sample_delay))
+    if (!SYS_Linux_GetPHCSample(iface->phc_fd, iface->phc_nocrossts, iface->precision,
+                                &iface->phc_mode, &sample_phc_ts, &sample_sys_ts, &err))
      return;

-    HCL_AccumulateSample(iface->clock, &sample_phc_ts, &sample_local_ts,
-                         sample_delay / 2.0);
+    LCL_CookTime(&sample_sys_ts, &sample_local_ts, NULL);
+    HCL_AccumulateSample(iface->clock, &sample_phc_ts, &sample_local_ts, err);

    update_interface_speed(iface);
  }
@@ -536,8 +488,7 @@ extract_udp_data(unsigned char *msg, NTP_Remote_Address *remote_addr, int len)

 int
 NIO_Linux_ProcessMessage(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr,
-                         NTP_Local_Timestamp *local_ts, struct msghdr *hdr,
-                         int length, int sock_fd, int if_index)
+                         NTP_Local_Timestamp *local_ts, struct msghdr *hdr, int length)
 {
  struct Interface *iface;
  struct cmsghdr *cmsg;
@@ -556,12 +507,13 @@ NIO_Linux_ProcessMessage(NTP_Remote_Address *remote_addr, NTP_Local_Address *loc
        LCL_CookTime(&ts3.ts[0], &local_ts->ts, &local_ts->err);
        local_ts->source = NTP_TS_KERNEL;
      } else if (!UTI_IsZeroTimespec(&ts3.ts[2])) {
-        iface = get_interface(if_index);
+        iface = get_interface(local_addr->if_index);
        if (iface) {
          process_hw_timestamp(iface, &ts3.ts[2], local_ts, !is_tx ? length : 0,
                               remote_addr->ip_addr.family);
        } else {
-          DEBUG_LOG(LOGF_NtpIOLinux, "HW clock not found for interface %d", if_index);
+          DEBUG_LOG(LOGF_NtpIOLinux, "HW clock not found for interface %d",
+                    local_addr->if_index);
        }
      }
    }
@@ -593,7 +545,7 @@ NIO_Linux_ProcessMessage(NTP_Remote_Address *remote_addr, NTP_Local_Address *loc

  DEBUG_LOG(LOGF_NtpIOLinux, "Received %d (%d) bytes from error queue for %s:%d fd=%d if=%d tss=%d",
            l2_length, length, UTI_IPToString(&remote_addr->ip_addr), remote_addr->port,
-            sock_fd, if_index, local_ts->source);
+            local_addr->sock_fd, local_addr->if_index, local_ts->source);

  /* Update assumed position of UDP data at layer 2 for next received packet */
  if (iface && length) {
--- a/ntp_io_linux.h
+++ b/ntp_io_linux.h
@@ -31,7 +31,6 @@ extern void NIO_Linux_Finalise(void);
 extern int NIO_Linux_SetTimestampSocketOptions(int sock_fd, int client_only, int *events);

 extern int NIO_Linux_ProcessMessage(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr,
-                                    NTP_Local_Timestamp *local_ts, struct msghdr *hdr, int length,
-                                    int sock_fd, int if_index);
+                                    NTP_Local_Timestamp *local_ts, struct msghdr *hdr, int length);

 extern int NIO_Linux_RequestTxTimestamp(struct msghdr *msg, int cmsglen, int sock_fd);
--- a/refclock.c
+++ b/refclock.c
@@ -2,7 +2,7 @@
  chronyd/chronyc - Programs for keeping computer clocks accurate.

 **********************************************************************
- * Copyright (C) Miroslav Lichvar  2009-2011, 2013-2014
+ * Copyright (C) Miroslav Lichvar  2009-2011, 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
@@ -505,6 +505,12 @@ RCL_AddPulse(RCL_Instance instance, struct timespec *pulse_time, double second)
  return 1;
 }

+double
+RCL_GetPrecision(RCL_Instance instance)
+{
+  return instance->precision;
+}
+
 static int
 valid_sample_time(RCL_Instance instance, struct timespec *raw, struct timespec *cooked)
 {
--- a/refclock.h
+++ b/refclock.h
@@ -71,5 +71,6 @@ extern char *RCL_GetDriverParameter(RCL_Instance instance);
 extern char *RCL_GetDriverOption(RCL_Instance instance, char *name);
 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 double RCL_GetPrecision(RCL_Instance instance);

 #endif
--- a/refclock_phc.c
+++ b/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
@@ -33,144 +33,67 @@

 #include "sysincl.h"

-#include <linux/ptp_clock.h>
-
 #include "refclock.h"
 #include "logging.h"
+#include "memory.h"
 #include "util.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;
 };

-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 int phc_initialise(RCL_Instance instance)
 {
-  struct ptp_clock_caps caps;
+  struct phc_instance *phc;
  int phc_fd;
  char *path;

  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(LOGF_Refclock, "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;

-  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);
+  close(phc->fd);
+  Free(phc);
 }

 static int phc_poll(RCL_Instance instance)
 {
-  struct phc_reading readings[NUM_READINGS];
-  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;
+  double offset, 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);

-  /* Find the fastest reading */
-  for (i = 0; i < NUM_READINGS; i++) {
-    delay = UTI_DiffTimespecsToDouble(&readings[i].sys_ts2, &readings[i].sys_ts1);
+  if (!SYS_Linux_GetPHCSample(phc->fd, phc->nocrossts, RCL_GetPrecision(instance),
+                              &phc->mode, &phc_ts, &sys_ts, &err))
+    return 0;

-    if (!i || best_delay > delay) {
-      best = i;
-      best_delay = delay;
-    }
-  }
+  offset = UTI_DiffTimespecsToDouble(&phc_ts, &sys_ts);

-  offset = UTI_DiffTimespecsToDouble(&readings[best].phc_ts, &readings[best].sys_ts2) +
-           best_delay / 2.0;
+  DEBUG_LOG(LOGF_Refclock, "PHC offset: %+.9f err: %.9f", offset, err);

-  DEBUG_LOG(LOGF_Refclock, "PHC offset: %+.9f delay: %.9f", offset, best_delay);
-
-  return RCL_AddSample(instance, &readings[best].sys_ts2, offset, LEAP_Normal);
+  return RCL_AddSample(instance, &sys_ts, offset, LEAP_Normal);
 }

 RefclockDriver RCL_PHC_driver = {
--- a/reference.c
+++ b/reference.c
@@ -1214,7 +1214,7 @@ REF_GetReferenceParams
    *leap_status = LEAP_Normal;
    
    *root_delay = 0.0;
-    *root_dispersion = LCL_GetSysPrecisionAsQuantum();
+    *root_dispersion = 0.0;
    
  } else {

--- a/regress.c
+++ b/regress.c
@@ -3,7 +3,7 @@

 **********************************************************************
 * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2011
+ * Copyright (C) Miroslav Lichvar  2011, 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
--- a/rtc_linux.c
+++ b/rtc_linux.c
@@ -187,6 +187,11 @@ accumulate_sample(time_t rtc, struct timespec *sys)
    discard_samples(NEW_FIRST_WHEN_FULL);
  }

+  /* Discard all samples if the RTC was stepped back (not our trim) */
+  if (n_samples > 0 && rtc_sec[n_samples - 1] - rtc >= rtc_trim[n_samples - 1]) {
+    DEBUG_LOG(LOGF_RtcLinux, "RTC samples discarded");
+    n_samples = 0;
+  }

  /* Always use most recent sample as reference */
  /* use sample only if n_sample is not negative*/
--- a/sched.c
+++ b/sched.c
@@ -3,7 +3,7 @@

 **********************************************************************
 * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2011, 2013-2015
+ * Copyright (C) Miroslav Lichvar  2011, 2013-2016
 * 
 * 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
--- a/sourcestats.c
+++ b/sourcestats.c
@@ -3,7 +3,7 @@

 **********************************************************************
 * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2011-2014
+ * Copyright (C) Miroslav Lichvar  2011-2014, 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
@@ -928,7 +928,7 @@ void
 SST_DoSourceReport(SST_Stats inst, RPT_SourceReport *report, struct timespec *now)
 {
  int i, j;
-  struct timespec ago;
+  struct timespec last_sample_time;

  if (inst->n_samples > 0) {
    i = get_runsbuf_index(inst, inst->n_samples - 1);
@@ -938,8 +938,10 @@ SST_DoSourceReport(SST_Stats inst, RPT_SourceReport *report, struct timespec *no
    report->latest_meas_err = 0.5*inst->root_delays[j] + inst->root_dispersions[j];
    report->stratum = inst->strata[j];

-    UTI_DiffTimespecs(&ago, now, &inst->sample_times[i]);
-    report->latest_meas_ago = ago.tv_sec;
+    /* Align the sample time to reduce the leak of the receive timestamp */
+    last_sample_time = inst->sample_times[i];
+    last_sample_time.tv_nsec = 0;
+    report->latest_meas_ago = UTI_DiffTimespecsToDouble(now, &last_sample_time);
  } else {
    report->latest_meas_ago = (uint32_t)-1;
    report->orig_latest_meas = 0;
--- a/stubs.c
+++ b/stubs.c
@@ -2,7 +2,7 @@
  chronyd/chronyc - Programs for keeping computer clocks accurate.

 **********************************************************************
- * Copyright (C) Miroslav Lichvar  2014-2015
+ * 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
--- a/sys_linux.c
+++ b/sys_linux.c
@@ -4,7 +4,7 @@
 **********************************************************************
 * Copyright (C) Richard P. Curnow  1997-2003
 * Copyright (C) John G. Hasler  2009
- * Copyright (C) Miroslav Lichvar  2009-2012, 2014-2015
+ * Copyright (C) Miroslav Lichvar  2009-2012, 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
@@ -47,13 +47,14 @@
 #include <sys/capability.h>
 #endif

+#if defined(FEAT_PHC) || defined(HAVE_LINUX_TIMESTAMPING)
+#include <linux/ptp_clock.h>
+#endif
+
 #ifdef FEAT_SCFILTER
 #include <sys/prctl.h>
 #include <seccomp.h>
 #include <termios.h>
-#if defined(FEAT_PHC) || defined(HAVE_LINUX_TIMESTAMPING)
-#include <linux/ptp_clock.h>
-#endif
 #ifdef FEAT_PPS
 #include <linux/pps.h>
 #endif
@@ -68,6 +69,7 @@
 #include "sys_linux.h"
 #include "sys_timex.h"
 #include "conf.h"
+#include "local.h"
 #include "logging.h"
 #include "privops.h"
 #include "util.h"
@@ -515,6 +517,9 @@ SYS_Linux_EnableSystemCallFilter(int level)
    FIONREAD, TCGETS,
 #if defined(FEAT_PHC) || defined(HAVE_LINUX_TIMESTAMPING)
    PTP_SYS_OFFSET,
+#ifdef PTP_SYS_OFFSET_PRECISE
+    PTP_SYS_OFFSET_PRECISE,
+#endif
 #endif
 #ifdef FEAT_PPS
    PPS_FETCH,
@@ -661,3 +666,151 @@ SYS_Linux_CheckKernelVersion(int req_major, int req_minor)

  return kernelvercmp(req_major, req_minor, 0, major, minor, patch) <= 0;
 }
+
+/* ================================================== */
+
+#if defined(FEAT_PHC) || defined(HAVE_LINUX_TIMESTAMPING)
+
+#define PHC_READINGS 10
+
+static int
+get_phc_sample(int phc_fd, double precision, struct timespec *phc_ts,
+               struct timespec *sys_ts, double *err)
+{
+  struct ptp_sys_offset sys_off;
+  struct timespec ts1, ts2, ts3, phc_tss[PHC_READINGS], sys_tss[PHC_READINGS];
+  double min_delay = 0.0, delays[PHC_READINGS], phc_sum, sys_sum, sys_prec;
+  int i, n;
+
+  /* Silence valgrind */
+  memset(&sys_off, 0, sizeof (sys_off));
+
+  sys_off.n_samples = PHC_READINGS;
+
+  if (ioctl(phc_fd, PTP_SYS_OFFSET, &sys_off)) {
+    DEBUG_LOG(LOGF_SysLinux, "ioctl(%s) failed : %s", "PTP_SYS_OFFSET", strerror(errno));
+    return 0;
+  }
+
+  for (i = 0; i < PHC_READINGS; i++) {
+    ts1.tv_sec = sys_off.ts[i * 2].sec;
+    ts1.tv_nsec = sys_off.ts[i * 2].nsec;
+    ts2.tv_sec = sys_off.ts[i * 2 + 1].sec;
+    ts2.tv_nsec = sys_off.ts[i * 2 + 1].nsec;
+    ts3.tv_sec = sys_off.ts[i * 2 + 2].sec;
+    ts3.tv_nsec = sys_off.ts[i * 2 + 2].nsec;
+
+    sys_tss[i] = ts1;
+    phc_tss[i] = ts2;
+    delays[i] = UTI_DiffTimespecsToDouble(&ts3, &ts1);
+
+    if (delays[i] <= 0.0)
+      /* Step in the middle of a PHC reading? */
+      return 0;
+
+    if (!i || delays[i] < min_delay)
+      min_delay = delays[i];
+  }
+
+  sys_prec = LCL_GetSysPrecisionAsQuantum();
+
+  /* Combine best readings */
+  for (i = n = 0, phc_sum = sys_sum = 0.0; i < PHC_READINGS; i++) {
+    if (delays[i] > min_delay + MAX(sys_prec, precision))
+      continue;
+
+    phc_sum += UTI_DiffTimespecsToDouble(&phc_tss[i], &phc_tss[0]);
+    sys_sum += UTI_DiffTimespecsToDouble(&sys_tss[i], &sys_tss[0]) + delays[i] / 2.0;
+    n++;
+  }
+
+  assert(n);
+
+  UTI_AddDoubleToTimespec(&phc_tss[0], phc_sum / n, phc_ts);
+  UTI_AddDoubleToTimespec(&sys_tss[0], sys_sum / n, sys_ts);
+  *err = MAX(min_delay / 2.0, precision);
+
+  return 1;
+}
+/* ================================================== */
+
+static int
+get_precise_phc_sample(int phc_fd, double precision, struct timespec *phc_ts,
+		       struct timespec *sys_ts, double *err)
+{
+#ifdef PTP_SYS_OFFSET_PRECISE
+  struct ptp_sys_offset_precise sys_off;
+
+  /* Silence valgrind */
+  memset(&sys_off, 0, sizeof (sys_off));
+
+  if (ioctl(phc_fd, PTP_SYS_OFFSET_PRECISE, &sys_off)) {
+    DEBUG_LOG(LOGF_SysLinux, "ioctl(%s) failed : %s", "PTP_SYS_OFFSET_PRECISE",
+              strerror(errno));
+    return 0;
+  }
+
+  phc_ts->tv_sec = sys_off.device.sec;
+  phc_ts->tv_nsec = sys_off.device.nsec;
+  sys_ts->tv_sec = sys_off.sys_realtime.sec;
+  sys_ts->tv_nsec = sys_off.sys_realtime.nsec;
+  *err = MAX(LCL_GetSysPrecisionAsQuantum(), precision);
+
+  return 1;
+#else
+  return 0;
+#endif
+}
+
+/* ================================================== */
+
+int
+SYS_Linux_OpenPHC(const char *path, int phc_index)
+{
+  struct ptp_clock_caps caps;
+  char phc_path[64];
+  int phc_fd;
+
+  if (!path) {
+    if (snprintf(phc_path, sizeof (phc_path), "/dev/ptp%d", phc_index) >= sizeof (phc_path))
+      return -1;
+    path = phc_path;
+  }
+
+  phc_fd = open(path, O_RDONLY);
+  if (phc_fd < 0) {
+    LOG(LOGS_ERR, LOGF_SysLinux, "Could not open %s : %s", path, strerror(errno));
+    return -1;
+  }
+
+  /* Make sure it is a PHC */
+  if (ioctl(phc_fd, PTP_CLOCK_GETCAPS, &caps)) {
+    LOG(LOGS_ERR, LOGF_SysLinux, "ioctl(%s) failed : %s", "PTP_CLOCK_GETCAPS", strerror(errno));
+    close(phc_fd);
+    return -1;
+  }
+
+  UTI_FdSetCloexec(phc_fd);
+
+  return phc_fd;
+}
+
+/* ================================================== */
+
+int
+SYS_Linux_GetPHCSample(int fd, int nocrossts, double precision, int *reading_mode,
+                       struct timespec *phc_ts, struct timespec *sys_ts, double *err)
+{
+  if ((*reading_mode == 2 || !*reading_mode) && !nocrossts &&
+      get_precise_phc_sample(fd, precision, phc_ts, sys_ts, err)) {
+    *reading_mode = 2;
+    return 1;
+  } else if ((*reading_mode == 1 || !*reading_mode) &&
+      get_phc_sample(fd, precision, phc_ts, sys_ts, err)) {
+    *reading_mode = 1;
+    return 1;
+  }
+  return 0;
+}
+
+#endif
--- a/sys_linux.h
+++ b/sys_linux.h
@@ -41,4 +41,9 @@ extern void SYS_Linux_SetScheduler(int SchedPriority);

 extern int SYS_Linux_CheckKernelVersion(int req_major, int req_minor);

+extern int SYS_Linux_OpenPHC(const char *path, int phc_index);
+
+extern int SYS_Linux_GetPHCSample(int fd, int nocrossts, double precision, int *reading_mode,
+                                  struct timespec *phc_ts, struct timespec *sys_ts, double *err);
+
 #endif  /* GOT_SYS_LINUX_H */
--- a/sys_timex.c
+++ b/sys_timex.c
@@ -158,7 +158,8 @@ set_sync_status(int synchronised, double est_error, double max_error)
  txc.esterror = est_error * 1.0e6;
  txc.maxerror = max_error * 1.0e6;

-  SYS_Timex_Adjust(&txc, 1);
+  if (SYS_Timex_Adjust(&txc, 1) < 0)
+    ;
 }

 /* ================================================== */
--- a/test/simulation/110-chronyc
+++ b/test/simulation/110-chronyc
@@ -20,8 +20,8 @@ RMS offset      : 0\.000...... seconds
 Frequency       : (99|100)\.... ppm fast
 Residual freq   : [+-][0-9]\.... ppm
 Skew            : [0-9]\.... ppm
-Root delay      : 0\.000... seconds
-Root dispersion : 0\.000... seconds
+Root delay      : 0\.000...... seconds
+Root dispersion : 0\.000...... seconds
 Update interval : [0-9]+\.. seconds
 Leap status     : Normal
 210 Number of sources = 1
--- a/test/simulation/119-smoothtime
+++ b/test/simulation/119-smoothtime
@@ -25,13 +25,21 @@ time_offset=-10
 client_server_options="minpoll 6 maxpoll 6"
 client_conf="corrtimeratio 100"
 min_sync_time=8000
-max_sync_time=8500
+max_sync_time=9000

 run_test || test_fail
 check_chronyd_exit || test_fail
 check_source_selection || test_fail
 check_sync || test_fail

+client_server_options="minpoll 6 maxpoll 6 xleave maxdelay 1e-1"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_source_selection || test_fail
+check_sync || test_fail
+
+client_server_options="minpoll 6 maxpoll 6"
 min_sync_time=$default_min_sync_time
 max_sync_time=$default_max_sync_time
 time_max_limit=11
--- a/test/unit/hwclock.c
+++ b/test/unit/hwclock.c
@@ -31,7 +31,7 @@ test_unit(void)

  LCL_Initialise();

-  clock = HCL_CreateInstance();
+  clock = HCL_CreateInstance(1.0);

  for (i = 0; i < 2000; i++) {
    UTI_ZeroTimespec(&start_hw_ts);
@@ -43,7 +43,7 @@ test_unit(void)

    freq = TST_GetRandomDouble(0.9, 1.1);
    jitter = TST_GetRandomDouble(10.0e-9, 1000.0e-9);
-    interval = TST_GetRandomDouble(MIN_SAMPLE_SEPARATION / 10, MIN_SAMPLE_SEPARATION * 10.0);
+    interval = TST_GetRandomDouble(0.1, 10.0);

    clock->n_samples = 0;
    clock->valid_coefs = 0;
@@ -68,5 +68,7 @@ test_unit(void)
    }
  }

+  HCL_DestroyInstance(clock);
+
  LCL_Finalise();
 }
--- a/test/unit/keys.c
+++ b/test/unit/keys.c
@@ -0,0 +1,147 @@
+/*
+ **********************************************************************
+ * 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.
+ * 
+ **********************************************************************
+ */
+
+#include <keys.c>
+#include "test.h"
+
+#define KEYS 100
+#define KEYFILE "keys.test-keys"
+
+static
+uint32_t write_random_key(FILE *f)
+{
+  const char *hash_name;
+  char key[128];
+  uint32_t id;
+  int i, length;
+
+  length = random() % sizeof (key) + 1;
+  length = MAX(length, 4);
+  UTI_GetRandomBytes(&id, sizeof (id));
+  UTI_GetRandomBytes(key, length);
+
+  switch (random() % 6) {
+#ifdef FEAT_SECHASH
+    case 0:
+      hash_name = "SHA1";
+      break;
+    case 1:
+      hash_name = "SHA256";
+      break;
+    case 2:
+      hash_name = "SHA384";
+      break;
+    case 3:
+      hash_name = "SHA512";
+      break;
+#endif
+    case 4:
+      hash_name = "MD5";
+      break;
+    default:
+      hash_name = "";
+  }
+
+  fprintf(f, "%u %s %s", id, hash_name, random() % 2 ? "HEX:" : "");
+  for (i = 0; i < length; i++)
+    fprintf(f, "%02hhX", key[i]);
+  fprintf(f, "\n");
+
+  return id;
+}
+
+static void
+generate_key_file(const char *name, uint32_t *keys)
+{
+  FILE *f;
+  int i;
+
+  f = fopen(name, "w");
+  TEST_CHECK(f);
+  for (i = 0; i < KEYS; i++)
+    keys[i] = write_random_key(f);
+  fclose(f);
+}
+
+void
+test_unit(void)
+{
+  int i, j, data_len, auth_len;
+  uint32_t keys[KEYS], key;
+  unsigned char data[100], auth[MAX_HASH_LENGTH];
+  char conf[][100] = {
+    "keyfile "KEYFILE
+  };
+
+  CNF_Initialise(0);
+  for (i = 0; i < sizeof conf / sizeof conf[0]; i++)
+    CNF_ParseLine(NULL, i + 1, conf[i]);
+
+  generate_key_file(KEYFILE, keys);
+  KEY_Initialise();
+
+  for (i = 0; i < 100; i++) {
+    DEBUG_LOG(0, "iteration %d", i);
+
+    if (i) {
+      generate_key_file(KEYFILE, keys);
+      KEY_Reload();
+    }
+
+    UTI_GetRandomBytes(data, sizeof (data));
+
+    for (j = 0; j < KEYS; j++) {
+      TEST_CHECK(KEY_KeyKnown(keys[j]));
+      TEST_CHECK(KEY_GetAuthDelay(keys[j]) >= 0);
+      TEST_CHECK(KEY_GetAuthLength(keys[j]) >= 16);
+
+      data_len = random() % (sizeof (data) + 1);
+      auth_len = KEY_GenerateAuth(keys[j], data, data_len, auth, sizeof (auth));
+      TEST_CHECK(auth_len >= 16);
+
+      TEST_CHECK(KEY_CheckAuth(keys[j], data, data_len, auth, auth_len, auth_len));
+
+      if (j > 0 && keys[j - 1] != keys[j])
+        TEST_CHECK(!KEY_CheckAuth(keys[j - 1], data, data_len, auth, auth_len, auth_len));
+
+      auth_len = random() % auth_len + 1;
+      if (auth_len < MAX_HASH_LENGTH)
+        auth[auth_len]++;
+      TEST_CHECK(KEY_CheckAuth(keys[j], data, data_len, auth, auth_len, auth_len));
+
+      auth[auth_len - 1]++;
+      TEST_CHECK(!KEY_CheckAuth(keys[j], data, data_len, auth, auth_len, auth_len));
+    }
+
+    for (j = 0; j < 1000; j++) {
+      UTI_GetRandomBytes(&key, sizeof (key));
+      if (KEY_KeyKnown(key))
+        continue;
+      TEST_CHECK(!KEY_GenerateAuth(j, data, data_len, auth, sizeof (auth)));
+      TEST_CHECK(!KEY_CheckAuth(j, data, data_len, auth, auth_len, auth_len));
+    }
+  }
+
+  unlink(KEYFILE);
+
+  KEY_Finalise();
+  CNF_Finalise();
+  HSH_Finalise();
+}
--- a/test/unit/ntp_core.c
+++ b/test/unit/ntp_core.c
@@ -0,0 +1,299 @@
+/*
+ **********************************************************************
+ * 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.
+ * 
+ **********************************************************************
+ */
+
+#include <config.h>
+#include <sysincl.h>
+#include <cmdparse.h>
+#include <conf.h>
+#include <keys.h>
+#include <ntp_io.h>
+#include <sched.h>
+#include <local.h>
+#include "test.h"
+
+static struct timespec current_time;
+static NTP_Receive_Buffer req_buffer, res_buffer;
+static int req_length, res_length;
+
+#define NIO_OpenServerSocket(addr) ((addr)->ip_addr.family != IPADDR_UNSPEC ? 100 : 0)
+#define NIO_CloseServerSocket(fd) assert(fd == 100)
+#define NIO_OpenClientSocket(addr) ((addr)->ip_addr.family != IPADDR_UNSPEC ? 101 : 0)
+#define NIO_CloseClientSocket(fd) assert(fd == 101)
+#define NIO_SendPacket(msg, to, from, len, process_tx) (memcpy(&req_buffer, msg, len), req_length = len, 1)
+#define SCH_AddTimeoutByDelay(delay, handler, arg) (1 ? 102 : (handler(arg), 1))
+#define SCH_AddTimeoutInClass(delay, separation, randomness, class, handler, arg) \
+  add_timeout_in_class(delay, separation, randomness, class, handler, arg)
+#define SCH_RemoveTimeout(id) assert(!id || id == 102)
+#define LCL_ReadRawTime(ts) (*ts = current_time)
+#define LCL_ReadCookedTime(ts, err) do {double *p = err; *ts = current_time; if (p) *p = 0.0;} while (0)
+#define SRC_UpdateReachability(inst, reach)
+#define SRC_ResetReachability(inst)
+
+static SCH_TimeoutID
+add_timeout_in_class(double min_delay, double separation, double randomness,
+                     SCH_TimeoutClass class, SCH_TimeoutHandler handler, SCH_ArbitraryArgument arg)
+{
+  return 102;
+}
+
+#include <ntp_core.c>
+
+static NCR_Instance inst;
+
+static void
+advance_time(double x)
+{
+  UTI_AddDoubleToTimespec(&current_time, x, &current_time);
+}
+
+static void
+send_request(void)
+{
+  NTP_Local_Address local_addr;
+  NTP_Local_Timestamp local_ts;
+  uint32_t prev_tx_count;
+
+  prev_tx_count = inst->report.total_tx_count;
+
+  transmit_timeout(inst);
+  TEST_CHECK(!inst->valid_rx);
+  TEST_CHECK(!inst->updated_timestamps);
+  TEST_CHECK(prev_tx_count + 1 == inst->report.total_tx_count);
+
+  advance_time(1e-4);
+
+  local_addr.ip_addr.family = IPADDR_UNSPEC;
+  local_addr.if_index = INVALID_IF_INDEX;
+  local_addr.sock_fd = 101;
+  local_ts.ts = current_time;
+  local_ts.err = 0.0;
+  local_ts.source = NTP_TS_DAEMON;
+
+  NCR_ProcessTxKnown(inst, &local_addr, &local_ts, &req_buffer.ntp_pkt, req_length);
+}
+
+static void
+send_response(int interleaved, int authenticated, int allow_update, int valid_ts, int valid_auth)
+{
+  NTP_Packet *req, *res;
+
+  req = &req_buffer.ntp_pkt;
+  res = &res_buffer.ntp_pkt;
+
+  TEST_CHECK(req_length >= NTP_NORMAL_PACKET_LENGTH);
+
+  res->lvm = NTP_LVM(LEAP_Normal, NTP_LVM_TO_VERSION(req->lvm),
+                     NTP_LVM_TO_MODE(req->lvm) == MODE_CLIENT ? MODE_SERVER : MODE_ACTIVE);
+  res->stratum = 1;
+  res->poll = req->poll;
+  res->precision = -20;
+  res->root_delay = UTI_DoubleToNtp32(0.1);
+  res->root_dispersion = UTI_DoubleToNtp32(0.1);
+  res->reference_id = 0;
+  UTI_ZeroNtp64(&res->reference_ts);
+  res->originate_ts = interleaved ? req->receive_ts : req->transmit_ts;
+
+  advance_time(TST_GetRandomDouble(1e-4, 1e-2));
+  UTI_TimespecToNtp64(&current_time, &res->receive_ts, NULL);
+  advance_time(TST_GetRandomDouble(-1e-4, 1e-3));
+  UTI_TimespecToNtp64(&current_time, &res->transmit_ts, NULL);
+  advance_time(TST_GetRandomDouble(1e-4, 1e-2));
+
+  if (!valid_ts) {
+    switch (random() % (allow_update ? 4 : 5)) {
+      case 0:
+        res->originate_ts.hi = random();
+        break;
+      case 1:
+        res->originate_ts.lo = random();
+        break;
+      case 2:
+        UTI_ZeroNtp64(&res->originate_ts);
+        break;
+      case 3:
+        UTI_ZeroNtp64(&res->receive_ts);
+        break;
+      case 4:
+        UTI_ZeroNtp64(&res->transmit_ts);
+        break;
+      default:
+        assert(0);
+    }
+  }
+
+  if (authenticated) {
+    res->auth_keyid = req->auth_keyid;
+    KEY_GenerateAuth(ntohl(res->auth_keyid), (unsigned char *)res, NTP_NORMAL_PACKET_LENGTH,
+                     res->auth_data, 16);
+    res_length = NTP_NORMAL_PACKET_LENGTH + 4 + 16;
+  } else {
+    res_length = NTP_NORMAL_PACKET_LENGTH;
+  }
+
+  if (!valid_auth) {
+    switch (random() % 3) {
+      case 0:
+        res->auth_keyid++;
+        break;
+      case 1:
+        res->auth_data[random() % 16]++;
+        break;
+      case 2:
+        res_length = NTP_NORMAL_PACKET_LENGTH;
+        break;
+      default:
+        assert(0);
+    }
+  }
+}
+
+static void
+process_response(int valid, int updated)
+{
+  NTP_Local_Address local_addr;
+  NTP_Local_Timestamp local_ts;
+  NTP_Packet *res;
+  uint32_t prev_rx_count, prev_valid_count;
+  struct timespec prev_rx_ts;
+  int prev_open_socket;
+
+  res = &res_buffer.ntp_pkt;
+
+  local_addr.ip_addr.family = IPADDR_UNSPEC;
+  local_addr.if_index = INVALID_IF_INDEX;
+  local_addr.sock_fd = NTP_LVM_TO_MODE(res->lvm) == MODE_ACTIVE ? 100 : 101;
+  local_ts.ts = current_time;
+  local_ts.err = 0.0;
+  local_ts.source = NTP_TS_DAEMON;
+
+  prev_rx_count = inst->report.total_rx_count;
+  prev_valid_count = inst->report.total_valid_count;
+  prev_rx_ts = inst->local_rx.ts;
+  prev_open_socket = inst->local_addr.sock_fd != INVALID_SOCK_FD;
+
+  NCR_ProcessRxKnown(inst, &local_addr, &local_ts, res, res_length);
+
+  if (prev_open_socket)
+    TEST_CHECK(prev_rx_count + 1 == inst->report.total_rx_count);
+  else
+    TEST_CHECK(prev_rx_count == inst->report.total_rx_count);
+
+  if (valid)
+    TEST_CHECK(prev_valid_count + 1 == inst->report.total_valid_count);
+  else
+    TEST_CHECK(prev_valid_count == inst->report.total_valid_count);
+
+  if (updated)
+    TEST_CHECK(UTI_CompareTimespecs(&inst->local_rx.ts, &prev_rx_ts));
+  else
+    TEST_CHECK(!UTI_CompareTimespecs(&inst->local_rx.ts, &prev_rx_ts));
+}
+
+void
+test_unit(void)
+{
+  char source_line[] = "127.0.0.1";
+  char conf[][100] = {
+    "port 0",
+    "keyfile ntp_core.keys"
+  };
+  int i, j, interleaved, authenticated, valid, updated, has_updated;
+  CPS_NTP_Source source;
+  NTP_Remote_Address remote_addr;
+
+  CNF_Initialise(0);
+  for (i = 0; i < sizeof conf / sizeof conf[0]; i++)
+    CNF_ParseLine(NULL, i + 1, conf[i]);
+
+  LCL_Initialise();
+  TST_RegisterDummyDrivers();
+  SCH_Initialise();
+  SRC_Initialise();
+  NIO_Initialise(IPADDR_UNSPEC);
+  NCR_Initialise();
+  REF_Initialise();
+  KEY_Initialise();
+
+  for (i = 0; i < 1000; i++) {
+    CPS_ParseNTPSourceAdd(source_line, &source);
+    if (random() % 2)
+      source.params.interleaved = 1;
+    if (random() % 2)
+      source.params.authkey = 1;
+
+    UTI_ZeroTimespec(&current_time);
+    advance_time(TST_GetRandomDouble(1.0, 1e9));
+
+    TST_GetRandomAddress(&remote_addr.ip_addr, IPADDR_UNSPEC, -1);
+    remote_addr.port = 123;
+
+    inst = NCR_GetInstance(&remote_addr, random() % 2 ? NTP_SERVER : NTP_PEER, &source.params);
+    NCR_StartInstance(inst);
+    has_updated = 0;
+
+    for (j = 0; j < 50; j++) {
+      DEBUG_LOG(0, "iteration %d, %d", i, j);
+
+      interleaved = random() % 2;
+      authenticated = random() % 2;
+      valid = (!interleaved || (source.params.interleaved && has_updated)) &&
+              (!source.params.authkey || authenticated);
+      updated = (valid || inst->mode == MODE_ACTIVE) &&
+                (!source.params.authkey || authenticated);
+      has_updated = has_updated || updated;
+
+      send_request();
+
+      send_response(interleaved, authenticated, 1, 0, 1);
+      process_response(0, inst->mode == MODE_CLIENT ? 0 : updated);
+
+      if (source.params.authkey) {
+        send_response(interleaved, authenticated, 1, 1, 0);
+        process_response(0, 0);
+      }
+
+      send_response(interleaved, authenticated, 1, 1, 1);
+      process_response(valid, updated);
+      process_response(0, 0);
+
+      advance_time(-1.0);
+
+      send_response(interleaved, authenticated, 1, 1, 1);
+      process_response(0, 0);
+
+      advance_time(1.0);
+
+      send_response(interleaved, authenticated, 1, 1, 1);
+      process_response(0, inst->mode == MODE_CLIENT ? 0 : updated);
+    }
+
+    NCR_DestroyInstance(inst);
+  }
+
+  KEY_Finalise();
+  REF_Finalise();
+  NCR_Finalise();
+  NIO_Finalise();
+  SRC_Finalise();
+  SCH_Finalise();
+  LCL_Finalise();
+  CNF_Finalise();
+  HSH_Finalise();
+}
--- a/test/unit/ntp_core.keys
+++ b/test/unit/ntp_core.keys
@@ -0,0 +1,2 @@
+1 MD5 HEX:38979C567358C0896F4D9D459A3C8B8478654579
+2 MD5 HEX:38979C567358C0896F4D9D459A3C8B8478654579
--- a/test/unit/ntp_sources.c
+++ b/test/unit/ntp_sources.c
@@ -96,4 +96,5 @@ test_unit(void)
  SCH_Finalise();
  LCL_Finalise();
  CNF_Finalise();
+  HSH_Finalise();
 }
--- a/test/unit/sources.c
+++ b/test/unit/sources.c
@@ -134,4 +134,5 @@ test_unit(void)
  SCH_Finalise();
  LCL_Finalise();
  CNF_Finalise();
+  HSH_Finalise();
 }
--- a/test/unit/util.c
+++ b/test/unit/util.c
@@ -74,6 +74,14 @@ void test_unit(void) {
  TEST_CHECK(!UTI_IsZeroTimespec(&ts));
  TEST_CHECK(!UTI_IsZeroNtp64(&ntp_ts));

+  ntp_ts.hi = 0;
+  ntp_ts.lo = 0;
+
+  UTI_Ntp64ToTimespec(&ntp_ts, &ts);
+  TEST_CHECK(UTI_IsZeroTimespec(&ts));
+  UTI_TimespecToNtp64(&ts, &ntp_ts, NULL);
+  TEST_CHECK(UTI_IsZeroNtp64(&ntp_ts));
+
  ntp_fuzz.hi = htonl(1);
  ntp_fuzz.lo = htonl(3);
  ntp_ts.hi = htonl(1);
--- a/util.c
+++ b/util.c
@@ -329,12 +329,14 @@ UTI_StringToIP(const char *addr, IPAddr *ip)

  if (inet_pton(AF_INET, addr, &in4) > 0) {
    ip->family = IPADDR_INET4;
+    ip->_pad = 0;
    ip->addr.in4 = ntohl(in4.s_addr);
    return 1;
  }

  if (inet_pton(AF_INET6, addr, &in6) > 0) {
    ip->family = IPADDR_INET6;
+    ip->_pad = 0;
    memcpy(ip->addr.in6, in6.s6_addr, sizeof (ip->addr.in6));
    return 1;
  }
@@ -344,6 +346,7 @@ UTI_StringToIP(const char *addr, IPAddr *ip)
  n = sscanf(addr, "%lu.%lu.%lu.%lu", &a, &b, &c, &d);
  if (n == 4) {
    ip->family = IPADDR_INET4;
+    ip->_pad = 0;
    ip->addr.in4 = ((a & 0xff) << 24) | ((b & 0xff) << 16) | 
                   ((c & 0xff) << 8) | (d & 0xff);
    return 1;
@@ -442,6 +445,7 @@ void
 UTI_IPNetworkToHost(IPAddr *src, IPAddr *dest)
 {
  dest->family = ntohs(src->family);
+  dest->_pad = 0;

  switch (dest->family) {
    case IPADDR_INET4:
@@ -754,8 +758,11 @@ UTI_Ntp64ToTimespec(NTP_int64 *src, struct timespec *dest)
 {
  uint32_t ntp_sec, ntp_frac;

-  /* As yet, there is no need to check for zero - all processing that
-     has to detect that case is in the NTP layer */
+  /* Zero is a special value */
+  if (UTI_IsZeroNtp64(src)) {
+    UTI_ZeroTimespec(dest);
+    return;
+  }

  ntp_sec = ntohl(src->hi);
  ntp_frac = ntohl(src->lo);
Author	SHA1	Message	Date
Miroslav Lichvar	5187c08c90	doc: update NEWS	2017-01-31 11:22:11 +01:00
Miroslav Lichvar	c8076ac10d	makefile: fix distclean target to not print errors	2017-01-31 11:22:11 +01:00
Miroslav Lichvar	362d155558	examples: improve configuration examples	2017-01-31 11:22:11 +01:00
Miroslav Lichvar	7b7eb0a6e5	examples: improve systemd unit files Add the PrivateTmp, ProtectHome, and ProtectSystem directives to better secure the system from chronyd. It's taken from the Debian chrony package.	2017-01-31 11:22:11 +01:00
Miroslav Lichvar	d96f49f67d	test: add keys unit test	2017-01-31 11:22:11 +01:00
Miroslav Lichvar	43ba5d2126	doc: document rekey in chronyc man page For some reason this useful command was never documented.	2017-01-31 11:22:11 +01:00
Miroslav Lichvar	48f7598fed	client: add rekey to help text	2017-01-31 11:22:11 +01:00
Miroslav Lichvar	510b22e96b	util: fix more coverity warnings Coverity doesn't seem to like the new field in the IPAddr struct (used as explicit padding of the structure) to be left uninitialized, even though it's never used for anything and is cleared by memset() in UTI_IPHostToNetwork() before leaving the process.	2017-01-31 11:22:10 +01:00
Miroslav Lichvar	0a0aff14d8	conf: add rawmeasurements log option While the measurements log can be useful for debugging problems in NTP configuration (e.g. authentication failures with symmetric keys), it seems most users are interested only in valid measurements (e.g. for producing graphs) and don't expect/handle entries where some of the RFC 5905 tests 1-7 failed. Modify the measurements log option to log only valid measurements, and for debugging purposes add a new rawmeasurements option.	2017-01-31 11:22:10 +01:00
Miroslav Lichvar	e225ac68bc	test: update 110-chronyc	2017-01-27 11:54:12 +01:00
Miroslav Lichvar	58060c40a5	doc: improve FAQ	2017-01-27 11:45:50 +01:00
Miroslav Lichvar	2ac1b3d5c4	client: print tracking delay/dispersion in nanosecond resolution	2017-01-27 11:35:38 +01:00
Miroslav Lichvar	c174566982	ntp: check supported flags before enabling HW timestamping	2017-01-27 11:35:38 +01:00
Miroslav Lichvar	60fca19d40	ntp: log info message when HW timestamping is enabled	2017-01-27 10:55:28 +01:00
Miroslav Lichvar	8bcb15b02f	doc: improve description of some server options	2017-01-27 10:55:28 +01:00
Miroslav Lichvar	65c2cebcd5	reference: report zero root dispersion with local reference The server's precision is supposed to be included in client's dispersion. Don't include it in the server's dispersion.	2017-01-27 10:55:28 +01:00
Miroslav Lichvar	2a51b45a43	test: fix memory leaks in unit tests	2017-01-27 10:55:28 +01:00
Miroslav Lichvar	5ac791665e	doc: update NEWS	2017-01-24 15:03:24 +01:00
Miroslav Lichvar	a4e3f83611	update copyright years	2017-01-24 15:01:38 +01:00
Miroslav Lichvar	8a837f9c2b	test: extend 119-smoothtime	2017-01-23 16:17:39 +01:00
Miroslav Lichvar	da2d33e9a8	ntp: fix time smoothing in interleaved mode When the server's transmit timestamp was updated with a kernel/HW timestamp, it didn't include the time smoothing offset. If the offset was larger than one second, the update failed and clients using the interleaved mode received less accurate timestamps. If the update succeeded, the clients received timestamps that were not adjusted for the time smoothing offset, which added an error of up to 0.5s/1s to their measured offset/delay. Fix the update to include the smoothing offset in the new timestamp.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	4b98dadae9	ntp: simplify UTI_Ntp64ToTimespec() callers Since UTI_Ntp64ToTimespec() was modified to handle zero timestamps, some of its callers don't need to do that anymore.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	86acea5c46	ntp: add interface index to NTP_Local_Address This will allow us to get the interface index when sending responses to clients.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	a60fc73e7b	refclock_phc: add nocrossts option	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	50f99ec5f4	conf: add nocrossts option to hwtimestamp directive This option disables the use of the PTP_SYS_OFFSET_PRECISE ioctl.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	31b6a14444	sys_linux: add support for PTP_SYS_OFFSET_PRECISE This is for hardware that can precisely cross timestamp the PHC with the system clock.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	9df4d36157	refclock_phc: use sys_linux code for reading PHC This drops support for non-ioctl reading of PHC.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	b70f0b674f	ntp: move PHC-specific code to sys_linux This will allow sharing of the code with the PHC refclock driver.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	510784077f	conf: add minpoll option to hwtimestamp directive	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	9800e397fb	hwclock: make minimum sampling separation configurable	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	1436d9961f	conf: add precision option to hwtimestamp directive	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	98f5d05925	ntp: include precision of PHC readings in their selection Include a fixed non-zero precision (100 nanosecond) in the selection of PHC readings.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	7a937c7652	conf: return hwtimestamp data in struct	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	b198d76676	ntp: include precision in maxdelay test	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	97d4203354	ntp: adapt sampling separation for short polling intervals	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	beaaaad162	ntp: allow sub-second polling intervals Change the minimum minpoll to -4, but keep the minimum maxpoll at 0 in order to not make it too easy to flood distant servers.	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	4e78975909	ntp: use current poll when backing off on KoD RATE	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	99147ed8f2	ntp: rename maxdelay constants	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	dec0d3bfc2	ntp: reset ntpdata report on address change	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	cd84c99e70	examples: improve chronyd.service	2017-01-23 15:58:55 +01:00
Miroslav Lichvar	d5c507975c	doc: update README	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	b4235abd36	update copyright years	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	1966085a97	test: add ntp_core unit test	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	e31e7af48f	test: make 119-smoothtime more reliable	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	adb9123fc3	test: extend util unit test	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	b0f7efd59e	util: handle zero in conversion of NTP timestamps Handle zero NTP timestamp in UTI_Ntp64ToTimespec() as a special value to make it symmetric with UTI_TimespecToNtp64(). This is needed since commit `d75f6830f1`, in which a timestamp is converted back and forth without checking for zero. It also makes zero NTP timestamps more apparent in debug output.	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	e28dfada8c	rtc: check for backward RTC steps When accumulating a new sample, check if the new RTC time is newer the last sample time. If it is not, discard all previous samples, assuming something has stepped the RTC, or it's a broken RTC/driver.	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	ac0b28cce6	sourcestats: align sample time used for source report This reduces leak of sample times (and receive timestamps which are related to sample times), which could be useful in off-path attacks on unauthenticated symmetric interleaved mode.	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	48b16ae66c	local: add assertion for precision	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	061579ec28	ntp: don't send packets with RX equal to TX Before sending an NTP packet, check whether the TX timestamp is not equal to the RX timestamp. If it is, generate a new TX timestamp and try again. This is extremely unlikely to happen in normal operation, but it is needed for reliable detection of the interleaved mode.	2017-01-12 16:34:28 +01:00
Miroslav Lichvar	f2f834e7e7	ntp: limit maxdelay parameters	2017-01-12 16:34:27 +01:00
Miroslav Lichvar	a7802e9a76	fix some coverity warnings	2017-01-12 16:34:27 +01:00