doc: update NEWS

Add a warning to the chrony.conf man page that MD5 keys cannot protect
NTP extension fields due to the length extension attack.

Makefile.in

@@ -33,9 +33,11 @@ CFLAGS = @CFLAGS@
 CPPFLAGS = @CPPFLAGS@
 LDFLAGS = @LDFLAGS@
 
+GETDATE_CFLAGS = @GETDATE_CFLAGS@
+
 EXTRA_OBJS = @EXTRA_OBJS@
 
-OBJS = array.o cmdparse.o conf.o local.o logging.o main.o memory.o quantiles.o \
+OBJS = array.o cmdparse.o conf.o leapdb.o local.o logging.o main.o memory.o quantiles.o \
        reference.o regress.o rtc.o samplefilt.o sched.o socket.o sources.o sourcestats.o \
        stubs.o smooth.o sys.o sys_null.o tempcomp.o util.o $(EXTRA_OBJS)
 
@@ -61,6 +63,8 @@ chronyd : $(OBJS)
 chronyc : $(CLI_OBJS)
 	$(CC) $(CFLAGS) -o chronyc $(CLI_OBJS) $(LDFLAGS) $(LIBS) $(EXTRA_CLI_LIBS)
 
+getdate.o: CFLAGS += $(GETDATE_CFLAGS)
+
 distclean : clean
 	$(MAKE) -C doc distclean
 	$(MAKE) -C test/unit distclean

NEWS

@@ -1,3 +1,52 @@
+New in version 4.6.1
+====================
+
+Enhancements
+------------
+* Add ntsaeads directive to enable only selected AEAD algorithms for NTS
+
+Workarounds
+-----------
+* Negotiate use of compliant NTS keys with AES-128-GCM-SIV AEAD algorithm
+  (by default the keys are generated differently than in RFC 8915 for
+  compatibility with chrony server and client versions 4.4, 4.5, and 4.6)
+* Switch to compliant NTS keys if first response from server is NTS NAK
+
+New in version 4.6
+==================
+
+Enhancements
+------------
+* Add activate option to local directive to set activation threshold
+* Add ipv4 and ipv6 options to server/pool/peer directive
+* Add kod option to ratelimit directive for server KoD RATE support
+* Add leapseclist directive to read NIST/IERS leap-seconds.list file
+* Add ptpdomain directive to set PTP domain for NTP over PTP
+* Allow disabling pidfile
+* Improve copy server option to accept unsynchronised status instantly
+* Log one selection failure on start
+* Add offset command to modify source offset correction
+* Add timestamp sources to ntpdata report
+
+Bug fixes
+---------
+* Fix crash on sources reload during initstepslew or RTC initialisation
+* Fix source refreshment to not repeat failed name resolving attempts
+
+New in version 4.5
+==================
+
+Enhancements
+------------
+* Add support for AES-GCM-SIV in GnuTLS
+* Add support for corrections from PTP transparent clocks
+* Add support for systemd socket activation
+
+Bug fixes
+---------
+* Fix presend in interleaved mode
+* Fix reloading of modified sources from sourcedir
+
 New in version 4.4
 ==================
 
@@ -14,6 +63,7 @@ Enhancements
 * Improve source replacement
 * Log important changes made by command requests (chronyc)
 * Refresh address of NTP sources periodically
+* Request nanosecond kernel RX timestamping on FreeBSD
 * Set DSCP for IPv6 packets
 * Shorten NTS-KE retry interval when network is down
 * Update seccomp filter for musl

README

@@ -12,7 +12,7 @@ a time service to other computers in the network.
 It is designed to perform well in a wide range of conditions, including
 intermittent network connections, heavily congested networks, changing
 temperatures (ordinary computer clocks are sensitive to temperature),
-and systems that do not run continuosly, or run on a virtual machine.
+and systems that do not run continuously, 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
@@ -47,32 +47,7 @@ Frequently Asked Questions (FAQ).
 The documentation is also available on the chrony web pages, accessible
 through the URL 
 
-    https://chrony.tuxfamily.org/
+    https://chrony-project.org/
-
-Where are new versions announced?
-=================================
-
-There is a low volume mailing list where new versions and other
-important news relating to chrony are announced.  You can join this list
-by sending mail with the subject "subscribe" to
-
-chrony-announce-request@chrony.tuxfamily.org
-
-How can I get support for chrony?
-=================================
-
-There are two other mailing lists relating to chrony.  chrony-users is a
-discussion list for users, e.g. for questions about chrony configuration
-and bug reports.  chrony-dev is a more technical list for developers,
-e.g. for submitting patches and discussing how new features should be
-implemented.  To subscribe to either of these lists, send a message with
-the subject "subscribe" to
-
-chrony-users-request@chrony.tuxfamily.org
-or
-chrony-dev-request@chrony.tuxfamily.org
-
-as applicable.
 
 License
 =======
@@ -100,6 +75,7 @@ Lonnie Abelbeck <lonnie@abelbeck.com>
 Benny Lyne Amorsen <benny@amorsen.dk>
 Andrew Bishop <amb@gedanken.demon.co.uk>
 Vincent Blut <vincent.debian@free.fr>
+Luca Boccassi <bluca@debian.org>
 Stephan I. Boettcher <stephan@nevis1.columbia.edu>
 David Bohman <debohman@gmail.com>
 Goswin Brederlow <brederlo@informatik.uni-tuebingen.de>
@@ -114,7 +90,9 @@ Christian Ehrhardt <christian.ehrhardt@canonical.com>
 Paul Elliott <pelliott@io.com>
 Robert Fairley <rfairley@redhat.com>
 Stefan R. Filipek <srfilipek@gmail.com>
+Andy Fiddaman <illumos@fiddaman.net>
 Mike Fleetwood <mike@rockover.demon.co.uk>
+Rob Gill <rrobgill@protonmail.com>
 Alexander Gretencord <arutha@gmx.de>
 Andrew Griffiths <agriffit@redhat.com>
 Walter Haidinger <walter.haidinger@gmx.at>
@@ -136,6 +114,7 @@ Paul Menzel <paulepanter@users.sourceforge.net>
 Vladimir Michl <vladimir.michl@seznam.cz>
 Victor Moroz <vim@prv.adlum.ru>
 Kalle Olavi Niemitalo  <tosi@stekt.oulu.fi>
+Patrick Oppenlander <patrick.oppenlander@gmail.com>
 Frank Otto <sandwichmacher@web.de>
 Denny Page <dennypage@me.com>
 Rupesh Patel <rupatel@redhat.com>
@@ -144,11 +123,13 @@ Gautier PHILIPPON <gautier.philippon@ensimag.grenoble-inp.fr>
 Andreas Piesk <apiesk@virbus.de>
 Mike Ryan <msr@hsilop.net>
 Baruch Siach <baruch@tkos.co.il>
+Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
 Foster Snowhill <forst@forstwoof.ru>
 Andreas Steinmetz <ast@domdv.de>
 NAKAMURA Takumi <takumi@ps.sakura.ne.jp>
 Timo Teras <timo.teras@iki.fi>
 Bill Unruh <unruh@physics.ubc.ca>
+Luke Valenta <lvalenta@cloudflare.com>
 Stephen Wadeley <swadeley@redhat.com>
 Bernhard Weiss <lisnablagh@web.de>
 Wolfgang Weisselberg <weissel@netcologne.de>

candm.h

@@ -110,7 +110,9 @@
 #define REQ_RELOAD_SOURCES 70
 #define REQ_DOFFSET2 71
 #define REQ_MODIFY_SELECTOPTS 72
-#define N_REQUEST_TYPES 73
+#define REQ_MODIFY_OFFSET 73
+#define REQ_LOCAL3 74
+#define N_REQUEST_TYPES 75
 
 /* Structure used to exchange timespecs independent of time_t size */
 typedef struct {
@@ -236,6 +238,8 @@ typedef struct {
   int32_t stratum;
   Float distance;
   int32_t orphan;
+  Float activate;
+  uint32_t reserved[2];
   int32_t EOR;
 } REQ_Local;
 
@@ -277,7 +281,10 @@ typedef struct {
 #define REQ_ADDSRC_BURST 0x100
 #define REQ_ADDSRC_NTS 0x200
 #define REQ_ADDSRC_COPY 0x400
-#define REQ_ADDSRC_EF_EXP1 0x800
+#define REQ_ADDSRC_EF_EXP_MONO_ROOT 0x800
+#define REQ_ADDSRC_EF_EXP_NET_CORRECTION 0x1000
+#define REQ_ADDSRC_IPV4 0x2000
+#define REQ_ADDSRC_IPV6 0x4000
 
 typedef struct {
   uint32_t type;
@@ -387,6 +394,13 @@ typedef struct {
   int32_t EOR;
 } REQ_Modify_SelectOpts;
 
+typedef struct {
+  IPAddr address;
+  uint32_t ref_id;
+  Float new_offset;
+  int32_t EOR;
+} REQ_Modify_Offset;
+
 /* ================================================== */
 
 #define PKT_TYPE_CMD_REQUEST 1
@@ -494,6 +508,7 @@ typedef struct {
     REQ_AuthData auth_data;
     REQ_SelectData select_data;
     REQ_Modify_SelectOpts modify_select_opts;
+    REQ_Modify_Offset modify_offset;
   } data; /* Command specific parameters */
 
   /* Padding used to prevent traffic amplification.  It only defines the
@@ -537,7 +552,8 @@ typedef struct {
 #define RPY_SELECT_DATA 23
 #define RPY_SERVER_STATS3 24
 #define RPY_SERVER_STATS4 25
-#define N_REPLY_TYPES 26
+#define RPY_NTP_DATA2 26
+#define N_REPLY_TYPES 27
 
 /* Status codes */
 #define STT_SUCCESS 0
@@ -760,7 +776,11 @@ typedef struct {
   uint32_t total_rx_count;
   uint32_t total_valid_count;
   uint32_t total_good_count;
-  uint32_t reserved[3];
+  uint32_t total_kernel_tx_ts;
+  uint32_t total_kernel_rx_ts;
+  uint32_t total_hw_tx_ts;
+  uint32_t total_hw_rx_ts;
+  uint32_t reserved[4];
   int32_t EOR;
 } RPY_NTPData;
 

client.c

@@ -4,7 +4,7 @@
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
  * Copyright (C) Lonnie Abelbeck  2016, 2018
- * Copyright (C) Miroslav Lichvar  2009-2021
+ * Copyright (C) Miroslav Lichvar  2009-2024
  * 
  * 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
@@ -344,6 +344,24 @@ parse_source_address(char *word, IPAddr *address)
 
 /* ================================================== */
 
+static int
+parse_source_address_or_refid(char *s, IPAddr *address, uint32_t *ref_id)
+{
+  address->family = IPADDR_UNSPEC;
+  *ref_id = 0;
+
+  /* Don't allow hostnames to avoid conflicts with reference IDs */
+  if (UTI_StringToIdIP(s, address) || UTI_StringToIP(s, address))
+    return 1;
+
+  if (CPS_ParseRefid(s, ref_id) > 0)
+    return 1;
+
+  return 0;
+}
+
+/* ================================================== */
+
 static int
 read_mask_address(char *line, IPAddr *mask, IPAddr *address)
 {
@@ -737,22 +755,24 @@ static int
 process_cmd_local(CMD_Request *msg, char *line)
 {
   int on_off, stratum = 0, orphan = 0;
-  double distance = 0.0;
+  double distance = 0.0, activate = 0.0;
 
   if (!strcmp(line, "off")) {
     on_off = 0;
-  } else if (CPS_ParseLocal(line, &stratum, &orphan, &distance)) {
+  } else if (CPS_ParseLocal(line, &stratum, &orphan, &distance, &activate)) {
     on_off = 1;
   } else {
     LOG(LOGS_ERR, "Invalid syntax for local command");
     return 0;
   }
 
-  msg->command = htons(REQ_LOCAL2);
+  msg->command = htons(REQ_LOCAL3);
   msg->data.local.on_off = htonl(on_off);
   msg->data.local.stratum = htonl(stratum);
   msg->data.local.distance = UTI_FloatHostToNetwork(distance);
   msg->data.local.orphan = htonl(orphan);
+  msg->data.local.activate = UTI_FloatHostToNetwork(activate);
+  memset(msg->data.local.reserved, 0, sizeof (msg->data.local.reserved));
 
   return 1;
 }
@@ -958,7 +978,12 @@ process_cmd_add_source(CMD_Request *msg, char *line)
           (data.params.burst ? REQ_ADDSRC_BURST : 0) |
           (data.params.nts ? REQ_ADDSRC_NTS : 0) |
           (data.params.copy ? REQ_ADDSRC_COPY : 0) |
-          (data.params.ext_fields & NTP_EF_FLAG_EXP1 ? REQ_ADDSRC_EF_EXP1 : 0) |
+          (data.params.ext_fields & NTP_EF_FLAG_EXP_MONO_ROOT ?
+           REQ_ADDSRC_EF_EXP_MONO_ROOT : 0) |
+          (data.params.ext_fields & NTP_EF_FLAG_EXP_NET_CORRECTION ?
+           REQ_ADDSRC_EF_EXP_NET_CORRECTION : 0) |
+          (data.family == IPADDR_INET4 ? REQ_ADDSRC_IPV4 : 0) |
+          (data.family == IPADDR_INET6 ? REQ_ADDSRC_IPV6 : 0) |
           convert_addsrc_sel_options(data.params.sel_options));
       msg->data.ntp_source.filter_length = htonl(data.params.filter_length);
       msg->data.ntp_source.cert_set = htonl(data.params.cert_set);
@@ -1026,6 +1051,7 @@ give_help(void)
     "selectopts <address|refid> <+|-options>\0Modify selection options\0"
     "reselect\0Force reselecting synchronisation source\0"
     "reselectdist <dist>\0Modify reselection distance\0"
+    "offset <address|refid> <offset>\0Modify offset correction\0"
     "\0\0"
     "NTP sources:\0\0"
     "activity\0Check how many NTP sources are online/offline\0"
@@ -1136,7 +1162,8 @@ command_name_generator(const char *text, int state)
     "clients", "cmdaccheck", "cmdallow", "cmddeny", "cyclelogs", "delete",
     "deny", "dns", "dump", "exit", "help", "keygen", "local", "makestep",
     "manual", "maxdelay", "maxdelaydevratio", "maxdelayratio", "maxpoll",
-    "maxupdateskew", "minpoll", "minstratum", "ntpdata", "offline", "online", "onoffline",
+    "maxupdateskew", "minpoll", "minstratum", "ntpdata",
+    "offline", "offset", "online", "onoffline",
     "polltarget", "quit", "refresh", "rekey", "reload", "reselect", "reselectdist", "reset",
     "retries", "rtcdata", "selectdata", "selectopts", "serverstats", "settime",
     "shutdown", "smoothing", "smoothtime", "sourcename", "sources", "sourcestats",
@@ -2326,7 +2353,7 @@ process_cmd_ntpdata(char *line)
 
     request.command = htons(REQ_NTP_DATA);
     UTI_IPHostToNetwork(&remote_addr, &request.data.ntp_data.ip_addr);
-    if (!request_reply(&request, &reply, RPY_NTP_DATA, 0))
+    if (!request_reply(&request, &reply, RPY_NTP_DATA2, 0))
       return 0;
 
     UTI_IPNetworkToHost(&reply.data.ntp_data.remote_addr, &remote_addr);
@@ -2362,7 +2389,11 @@ process_cmd_ntpdata(char *line)
                  "Total TX        : %U\n"
                  "Total RX        : %U\n"
                  "Total valid RX  : %U\n"
-                 "Total good RX   : %U\n",
+                 "Total good RX   : %U\n"
+                 "Total kernel TX : %U\n"
+                 "Total kernel RX : %U\n"
+                 "Total HW TX     : %U\n"
+                 "Total HW RX     : %U\n",
                  UTI_IPToString(&remote_addr), UTI_IPToRefid(&remote_addr),
                  ntohs(reply.data.ntp_data.remote_port),
                  UTI_IPToString(&local_addr), UTI_IPToRefid(&local_addr),
@@ -2390,6 +2421,10 @@ process_cmd_ntpdata(char *line)
                  ntohl(reply.data.ntp_data.total_rx_count),
                  ntohl(reply.data.ntp_data.total_valid_count),
                  ntohl(reply.data.ntp_data.total_good_count),
+                 ntohl(reply.data.ntp_data.total_kernel_tx_ts),
+                 ntohl(reply.data.ntp_data.total_kernel_rx_ts),
+                 ntohl(reply.data.ntp_data.total_hw_tx_ts),
+                 ntohl(reply.data.ntp_data.total_hw_rx_ts),
                  REPORT_END);
   }
 
@@ -2845,6 +2880,34 @@ process_cmd_activity(const char *line)
 
 /* ================================================== */
 
+static int
+process_cmd_offset(CMD_Request *msg, char *line)
+{
+  uint32_t ref_id;
+  IPAddr ip_addr;
+  double offset;
+  char *src;
+
+  src = line;
+  line = CPS_SplitWord(line);
+
+  if (!parse_source_address_or_refid(src, &ip_addr, &ref_id) ||
+      sscanf(line, "%lf", &offset) != 1) {
+    LOG(LOGS_ERR, "Invalid syntax for offset command");
+    return 0;
+  }
+
+  UTI_IPHostToNetwork(&ip_addr, &msg->data.modify_offset.address);
+  msg->data.modify_offset.ref_id = htonl(ref_id);
+  msg->data.modify_offset.new_offset = UTI_FloatHostToNetwork(offset);
+
+  msg->command = htons(REQ_MODIFY_OFFSET);
+
+  return 1;
+}
+
+/* ================================================== */
+
 static int
 process_cmd_reselectdist(CMD_Request *msg, char *line)
 {
@@ -2926,15 +2989,10 @@ process_cmd_selectopts(CMD_Request *msg, char *line)
 
   src = line;
   line = CPS_SplitWord(line);
-  ref_id = 0;
 
-  /* Don't allow hostnames to avoid conflicts with reference IDs */
+  if (!parse_source_address_or_refid(src, &ip_addr, &ref_id)) {
-  if (!UTI_StringToIdIP(src, &ip_addr) && !UTI_StringToIP(src, &ip_addr)) {
+    LOG(LOGS_ERR, "Invalid syntax for selectopts command");
-    ip_addr.family = IPADDR_UNSPEC;
+    return 0;
-    if (CPS_ParseRefid(src, &ref_id) == 0) {
-      LOG(LOGS_ERR, "Invalid syntax for selectopts command");
-      return 0;
-    }
   }
 
   mask = options = 0;
@@ -3236,6 +3294,8 @@ process_line(char *line)
     ret = process_cmd_ntpdata(line);
   } else if (!strcmp(command, "offline")) {
     do_normal_submit = process_cmd_offline(&tx_message, line);
+  } else if (!strcmp(command, "offset")) {
+    do_normal_submit = process_cmd_offset(&tx_message, line);
   } else if (!strcmp(command, "online")) {
     do_normal_submit = process_cmd_online(&tx_message, line);
   } else if (!strcmp(command, "onoffline")) {
@@ -3380,7 +3440,7 @@ static void
 display_gpl(void)
 {
     printf("chrony version %s\n"
-           "Copyright (C) 1997-2003, 2007, 2009-2022 Richard P. Curnow and others\n"
+           "Copyright (C) 1997-2003, 2007, 2009-2024 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",

clientlog.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2009, 2015-2017, 2021
+ * Copyright (C) Miroslav Lichvar  2009, 2015-2017, 2021, 2024
  * 
  * 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
@@ -117,6 +117,14 @@ static int token_shift[MAX_SERVICES];
 
 static int leak_rate[MAX_SERVICES];
 
+/* Rates at which responses requesting clients to reduce their rate
+   (e.g. NTP KoD RATE) are randomly allowed (in log2, but 0 means disabled) */
+
+#define MIN_KOD_RATE 0
+#define MAX_KOD_RATE 4
+
+static int kod_rate[MAX_SERVICES];
+
 /* Limit intervals in log2 */
 static int limit_interval[MAX_SERVICES];
 
@@ -354,18 +362,19 @@ set_bucket_params(int interval, int burst, uint16_t *max_tokens,
 void
 CLG_Initialise(void)
 {
-  int i, interval, burst, lrate, slots2;
+  int i, interval, burst, lrate, krate, slots2;
 
   for (i = 0; i < MAX_SERVICES; i++) {
     max_tokens[i] = 0;
     tokens_per_hit[i] = 0;
     token_shift[i] = 0;
     leak_rate[i] = 0;
+    kod_rate[i] = 0;
     limit_interval[i] = MIN_LIMIT_INTERVAL;
 
     switch (i) {
       case CLG_NTP:
-        if (!CNF_GetNTPRateLimit(&interval, &burst, &lrate))
+        if (!CNF_GetNTPRateLimit(&interval, &burst, &lrate, &krate))
           continue;
         break;
       case CLG_NTSKE:
@@ -382,6 +391,7 @@ CLG_Initialise(void)
 
     set_bucket_params(interval, burst, &max_tokens[i], &tokens_per_hit[i], &token_shift[i]);
     leak_rate[i] = CLAMP(MIN_LEAK_RATE, lrate, MAX_LEAK_RATE);
+    kod_rate[i] = CLAMP(MIN_KOD_RATE, krate, MAX_KOD_RATE);
     limit_interval[i] = CLAMP(MIN_LIMIT_INTERVAL, interval, MAX_LIMIT_INTERVAL);
   }
 
@@ -579,28 +589,28 @@ CLG_LogServiceAccess(CLG_Service service, IPAddr *client, struct timespec *now)
 /* ================================================== */
 
 static int
-limit_response_random(int leak_rate)
+limit_response_random(int rate)
 {
   static uint32_t rnd;
   static int bits_left = 0;
   int r;
 
-  if (bits_left < leak_rate) {
+  if (bits_left < rate) {
     UTI_GetRandomBytes(&rnd, sizeof (rnd));
     bits_left = 8 * sizeof (rnd);
   }
 
-  /* Return zero on average once per 2^leak_rate */
+  /* Return zero on average once per 2^rate */
-  r = rnd % (1U << leak_rate) ? 1 : 0;
+  r = rnd % (1U << rate) ? 1 : 0;
-  rnd >>= leak_rate;
+  rnd >>= rate;
-  bits_left -= leak_rate;
+  bits_left -= rate;
 
   return r;
 }
 
 /* ================================================== */
 
-int
+CLG_Limit
 CLG_LimitServiceRate(CLG_Service service, int index)
 {
   Record *record;
@@ -609,14 +619,14 @@ CLG_LimitServiceRate(CLG_Service service, int index)
   check_service_number(service);
 
   if (tokens_per_hit[service] == 0)
-    return 0;
+    return CLG_PASS;
 
   record = ARR_GetElement(records, index);
   record->drop_flags &= ~(1U << service);
 
   if (record->tokens[service] >= tokens_per_hit[service]) {
     record->tokens[service] -= tokens_per_hit[service];
-    return 0;
+    return CLG_PASS;
   }
 
   drop = limit_response_random(leak_rate[service]);
@@ -632,14 +642,18 @@ CLG_LimitServiceRate(CLG_Service service, int index)
 
   if (!drop) {
     record->tokens[service] = 0;
-    return 0;
+    return CLG_PASS;
+  }
+
+  if (kod_rate[service] > 0 && !limit_response_random(kod_rate[service])) {
+    return CLG_KOD;
   }
 
   record->drop_flags |= 1U << service;
   record->drops[service]++;
   total_drops[service]++;
 
-  return 1;
+  return CLG_DROP;
 }
 
 /* ================================================== */

clientlog.h

@@ -37,11 +37,17 @@ typedef enum {
   CLG_CMDMON,
 } CLG_Service;
 
+typedef enum {
+  CLG_PASS = 0,
+  CLG_DROP,
+  CLG_KOD,
+} CLG_Limit;
+
 extern void CLG_Initialise(void);
 extern void CLG_Finalise(void);
 extern int CLG_GetClientIndex(IPAddr *client);
 extern int CLG_LogServiceAccess(CLG_Service service, IPAddr *client, struct timespec *now);
-extern int CLG_LimitServiceRate(CLG_Service service, int index);
+extern CLG_Limit CLG_LimitServiceRate(CLG_Service service, int index);
 extern void CLG_UpdateNtpStats(int auth, NTP_Timestamp_Source rx_ts_src,
                                NTP_Timestamp_Source tx_ts_src);
 extern int CLG_GetNtpMinPoll(void);

cmdmon.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2009-2016, 2018-2021
+ * Copyright (C) Miroslav Lichvar  2009-2016, 2018-2024
  * 
  * 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
@@ -145,6 +145,8 @@ static const char permissions[] = {
   PERMIT_AUTH, /* RELOAD_SOURCES */
   PERMIT_AUTH, /* DOFFSET2 */
   PERMIT_AUTH, /* MODIFY_SELECTOPTS */
+  PERMIT_AUTH, /* MODIFY_OFFSET */
+  PERMIT_AUTH, /* LOCAL3 */
 };
 
 /* ================================================== */
@@ -530,7 +532,8 @@ handle_local(CMD_Request *rx_message, CMD_Reply *tx_message)
   if (ntohl(rx_message->data.local.on_off)) {
     REF_EnableLocal(ntohl(rx_message->data.local.stratum),
                     UTI_FloatNetworkToHost(rx_message->data.local.distance),
-                    ntohl(rx_message->data.local.orphan));
+                    ntohl(rx_message->data.local.orphan),
+                    UTI_FloatNetworkToHost(rx_message->data.local.activate));
   } else {
     REF_DisableLocal();
   }
@@ -720,9 +723,10 @@ handle_add_source(CMD_Request *rx_message, CMD_Reply *tx_message)
 {
   NTP_Source_Type type;
   SourceParameters params;
+  int family, pool, port;
   NSR_Status status;
+  uint32_t flags;
   char *name;
-  int pool, port;
   
   switch (ntohl(rx_message->data.ntp_source.type)) {
     case REQ_ADDSRC_SERVER:
@@ -750,6 +754,10 @@ handle_add_source(CMD_Request *rx_message, CMD_Reply *tx_message)
       return;
   }
 
+  flags = ntohl(rx_message->data.ntp_source.flags);
+
+  family = flags & REQ_ADDSRC_IPV4 ? IPADDR_INET4 :
+           flags & REQ_ADDSRC_IPV6 ? IPADDR_INET6 : IPADDR_UNSPEC;
   port = ntohl(rx_message->data.ntp_source.port);
   params.minpoll = ntohl(rx_message->data.ntp_source.minpoll);
   params.maxpoll = ntohl(rx_message->data.ntp_source.maxpoll);
@@ -775,19 +783,19 @@ handle_add_source(CMD_Request *rx_message, CMD_Reply *tx_message)
   params.asymmetry = UTI_FloatNetworkToHost(rx_message->data.ntp_source.asymmetry);
   params.offset = UTI_FloatNetworkToHost(rx_message->data.ntp_source.offset);
 
-  params.connectivity = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_ONLINE ?
+  params.connectivity = flags & REQ_ADDSRC_ONLINE ? SRC_ONLINE : SRC_OFFLINE;
-                        SRC_ONLINE : SRC_OFFLINE;
+  params.auto_offline = !!(flags & REQ_ADDSRC_AUTOOFFLINE);
-  params.auto_offline = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_AUTOOFFLINE ? 1 : 0;
+  params.iburst = !!(flags & REQ_ADDSRC_IBURST);
-  params.iburst = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_IBURST ? 1 : 0;
+  params.interleaved = !!(flags & REQ_ADDSRC_INTERLEAVED);
-  params.interleaved = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_INTERLEAVED ? 1 : 0;
+  params.burst = !!(flags & REQ_ADDSRC_BURST);
-  params.burst = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_BURST ? 1 : 0;
+  params.nts = !!(flags & REQ_ADDSRC_NTS);
-  params.nts = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_NTS ? 1 : 0;
+  params.copy = !!(flags & REQ_ADDSRC_COPY);
-  params.copy = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_COPY ? 1 : 0;
+  params.ext_fields = (flags & REQ_ADDSRC_EF_EXP_MONO_ROOT ? NTP_EF_FLAG_EXP_MONO_ROOT : 0) |
-  params.ext_fields =
+                      (flags & REQ_ADDSRC_EF_EXP_NET_CORRECTION ?
-    ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_EF_EXP1 ? NTP_EF_FLAG_EXP1 : 0;
+                       NTP_EF_FLAG_EXP_NET_CORRECTION : 0);
   params.sel_options = convert_addsrc_select_options(ntohl(rx_message->data.ntp_source.flags));
 
-  status = NSR_AddSourceByName(name, port, pool, type, &params, NULL);
+  status = NSR_AddSourceByName(name, family, port, pool, type, &params, NULL);
   switch (status) {
     case NSR_Success:
       break;
@@ -805,6 +813,8 @@ handle_add_source(CMD_Request *rx_message, CMD_Reply *tx_message)
       tx_message->status = htons(STT_INVALIDNAME);
       break;
     case NSR_InvalidAF:
+      tx_message->status = htons(STT_INVALIDAF);
+      break;
     case NSR_NoSuchSource:
       assert(0);
       break;
@@ -1223,7 +1233,7 @@ handle_ntp_data(CMD_Request *rx_message, CMD_Reply *tx_message)
     return;
   }
 
-  tx_message->reply = htons(RPY_NTP_DATA);
+  tx_message->reply = htons(RPY_NTP_DATA2);
   UTI_IPHostToNetwork(&report.remote_addr, &tx_message->data.ntp_data.remote_addr);
   UTI_IPHostToNetwork(&report.local_addr, &tx_message->data.ntp_data.local_addr);
   tx_message->data.ntp_data.remote_port = htons(report.remote_port);
@@ -1251,6 +1261,10 @@ handle_ntp_data(CMD_Request *rx_message, CMD_Reply *tx_message)
   tx_message->data.ntp_data.total_rx_count = htonl(report.total_rx_count);
   tx_message->data.ntp_data.total_valid_count = htonl(report.total_valid_count);
   tx_message->data.ntp_data.total_good_count = htonl(report.total_good_count);
+  tx_message->data.ntp_data.total_kernel_tx_ts = htonl(report.total_kernel_tx_ts);
+  tx_message->data.ntp_data.total_kernel_rx_ts = htonl(report.total_kernel_rx_ts);
+  tx_message->data.ntp_data.total_hw_tx_ts = htonl(report.total_hw_tx_ts);
+  tx_message->data.ntp_data.total_hw_rx_ts = htonl(report.total_hw_rx_ts);
   memset(tx_message->data.ntp_data.reserved, 0xff, sizeof (tx_message->data.ntp_data.reserved));
 }
 
@@ -1407,6 +1421,24 @@ handle_modify_selectopts(CMD_Request *rx_message, CMD_Reply *tx_message)
     tx_message->status = htons(STT_NOSUCHSOURCE);
 }
 
+/* ================================================== */
+
+static void
+handle_modify_offset(CMD_Request *rx_message, CMD_Reply *tx_message)
+{
+  uint32_t ref_id;
+  IPAddr ip_addr;
+  double offset;
+
+  UTI_IPNetworkToHost(&rx_message->data.modify_offset.address, &ip_addr);
+  ref_id = ntohl(rx_message->data.modify_offset.ref_id);
+  offset = UTI_FloatNetworkToHost(rx_message->data.modify_offset.new_offset);
+
+  if ((ip_addr.family != IPADDR_UNSPEC && !NSR_ModifyOffset(&ip_addr, offset)) ||
+      (ip_addr.family == IPADDR_UNSPEC && !RCL_ModifyOffset(ref_id, offset)))
+    tx_message->status = htons(STT_NOSUCHSOURCE);
+}
+
 /* ================================================== */
 /* Read a packet and process it */
 
@@ -1481,9 +1513,10 @@ read_from_cmd_socket(int sock_fd, int event, void *anything)
 
   /* Don't reply to all requests from hosts other than localhost if the rate
      is excessive */
-  if (!localhost && log_index >= 0 && CLG_LimitServiceRate(CLG_CMDMON, log_index)) {
+  if (!localhost && log_index >= 0 &&
-      DEBUG_LOG("Command packet discarded to limit response rate");
+      CLG_LimitServiceRate(CLG_CMDMON, log_index) != CLG_PASS) {
-      return;
+    DEBUG_LOG("Command packet discarded to limit response rate");
+    return;
   }
 
   expected_length = PKL_CommandLength(&rx_message);
@@ -1619,7 +1652,7 @@ read_from_cmd_socket(int sock_fd, int event, void *anything)
           handle_settime(&rx_message, &tx_message);
           break;
 
-        case REQ_LOCAL2:
+        case REQ_LOCAL3:
           handle_local(&rx_message, &tx_message);
           break;
 
@@ -1807,6 +1840,10 @@ read_from_cmd_socket(int sock_fd, int event, void *anything)
           handle_modify_selectopts(&rx_message, &tx_message);
           break;
 
+        case REQ_MODIFY_OFFSET:
+          handle_modify_offset(&rx_message, &tx_message);
+          break;
+
         default:
           DEBUG_LOG("Unhandled command %d", rx_command);
           tx_message.status = htons(STT_FAILED);

cmdparse.c

@@ -46,6 +46,7 @@ CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src)
   uint32_t ef_type;
   int n, sel_option;
   
+  src->family = IPADDR_UNSPEC;
   src->port = SRC_DEFAULT_PORT;
   src->params.minpoll = SRC_DEFAULT_MINPOLL;
   src->params.maxpoll = SRC_DEFAULT_MAXPOLL;
@@ -115,8 +116,11 @@ CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src)
       if (sscanf(line, "%"SCNx32"%n", &ef_type, &n) != 1)
         return 0;
       switch (ef_type) {
-        case NTP_EF_EXP1:
+        case NTP_EF_EXP_MONO_ROOT:
-          src->params.ext_fields |= NTP_EF_FLAG_EXP1;
+          src->params.ext_fields |= NTP_EF_FLAG_EXP_MONO_ROOT;
+          break;
+        case NTP_EF_EXP_NET_CORRECTION:
+          src->params.ext_fields |= NTP_EF_FLAG_EXP_NET_CORRECTION;
           break;
         default:
           return 0;
@@ -124,6 +128,10 @@ CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src)
     } else if (!strcasecmp(cmd, "filter")) {
       if (sscanf(line, "%d%n", &src->params.filter_length, &n) != 1)
         return 0;
+    } else if (!strcasecmp(cmd, "ipv4")) {
+      src->family = IPADDR_INET4;
+    } else if (!strcasecmp(cmd, "ipv6")) {
+      src->family = IPADDR_INET6;
     } else if (!strcasecmp(cmd, "maxdelay")) {
       if (sscanf(line, "%lf%n", &src->params.max_delay, &n) != 1)
         return 0;
@@ -288,13 +296,14 @@ CPS_ParseAllowDeny(char *line, int *all, IPAddr *ip, int *subnet_bits)
 /* ================================================== */
 
 int
-CPS_ParseLocal(char *line, int *stratum, int *orphan, double *distance)
+CPS_ParseLocal(char *line, int *stratum, int *orphan, double *distance, double *activate)
 {
   int n;
   char *cmd;
 
   *stratum = 10;
   *distance = 1.0;
+  *activate = 0.0;
   *orphan = 0;
 
   while (*line) {
@@ -311,6 +320,9 @@ CPS_ParseLocal(char *line, int *stratum, int *orphan, double *distance)
     } else if (!strcasecmp(cmd, "distance")) {
       if (sscanf(line, "%lf%n", distance, &n) != 1)
         return 0;
+    } else if (!strcasecmp(cmd, "activate")) {
+      if (sscanf(line, "%lf%n", activate, &n) != 1)
+        return 0;
     } else {
       return 0;
     }

cmdparse.h

@@ -32,6 +32,7 @@
 
 typedef struct {
   char *name;
+  int family;
   int port;
   SourceParameters params;
 } CPS_NTP_Source;
@@ -46,7 +47,7 @@ extern int CPS_GetSelectOption(char *option);
 extern int CPS_ParseAllowDeny(char *line, int *all, IPAddr *ip, int *subnet_bits);
 
 /* Parse a command to enable local reference */
-extern int CPS_ParseLocal(char *line, int *stratum, int *orphan, double *distance);
+extern int CPS_ParseLocal(char *line, int *stratum, int *orphan, double *distance, double *activate);
 
 /* Remove extra white-space and comments */
 extern void CPS_NormalizeLine(char *line);

conf.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2009-2017, 2020
+ * Copyright (C) Miroslav Lichvar  2009-2017, 2020, 2024
  * 
  * 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
@@ -57,6 +57,7 @@ static int parse_string(char *line, char **result);
 static int parse_int(char *line, int *result);
 static int parse_double(char *line, double *result);
 static int parse_null(char *line);
+static int parse_ints(char *line, ARR_Instance array);
 
 static void parse_allow_deny(char *line, ARR_Instance restrictions, int allow);
 static void parse_authselectmode(char *);
@@ -78,8 +79,9 @@ static void parse_makestep(char *);
 static void parse_maxchange(char *);
 static void parse_ntsserver(char *, ARR_Instance files);
 static void parse_ntstrustedcerts(char *);
+static void parse_pidfile(char *line);
 static void parse_ratelimit(char *line, int *enabled, int *interval,
-                            int *burst, int *leak);
+                            int *burst, int *leak, int *kod);
 static void parse_refclock(char *);
 static void parse_smoothtime(char *);
 static void parse_source(char *line, char *type, int fatal);
@@ -129,6 +131,7 @@ static int enable_local=0;
 static int local_stratum;
 static int local_orphan;
 static double local_distance;
+static double local_activate;
 
 /* Threshold (in seconds) - if absolute value of initial error is less
    than this, slew instead of stepping */
@@ -220,6 +223,7 @@ static int ntp_ratelimit_enabled = 0;
 static int ntp_ratelimit_interval = 3;
 static int ntp_ratelimit_burst = 8;
 static int ntp_ratelimit_leak = 2;
+static int ntp_ratelimit_kod = 0;
 static int nts_ratelimit_enabled = 0;
 static int nts_ratelimit_interval = 6;
 static int nts_ratelimit_burst = 8;
@@ -249,13 +253,19 @@ static REF_LeapMode leapsec_mode = REF_LeapModeSystem;
 /* Name of a system timezone containing leap seconds occuring at midnight */
 static char *leapsec_tz = NULL;
 
+/* File name of leap seconds list, usually /usr/share/zoneinfo/leap-seconds.list */
+static char *leapsec_list = NULL;
+
 /* Name of the user to which will be dropped root privileges. */
 static char *user;
 
 /* Address refresh interval */
 static int refresh = 1209600; /* 2 weeks */
 
+#define DEFAULT_NTS_AEADS "30 15"
+
 /* NTS server and client configuration */
+static ARR_Instance nts_aeads; /* array of int */
 static char *nts_dump_dir = NULL;
 static char *nts_ntp_server = NULL;
 static ARR_Instance nts_server_cert_files; /* array of (char *) */
@@ -282,19 +292,23 @@ static double hwts_timeout = 0.001;
 
 /* PTP event port (disabled by default) */
 static int ptp_port = 0;
+/* PTP domain number of NTP-over-PTP messages */
+static int ptp_domain = 123;
 
 typedef struct {
   NTP_Source_Type type;
   int pool;
   CPS_NTP_Source params;
+  NSR_Status status;
+  uint32_t conf_id;
 } NTP_Source;
 
 /* Array of NTP_Source */
 static ARR_Instance ntp_sources;
 /* Array of (char *) */
 static ARR_Instance ntp_source_dirs;
-/* Array of uint32_t corresponding to ntp_sources (for sourcedirs reload) */
+/* Flag indicating ntp_sources is used for sourcedirs after config load */
-static ARR_Instance ntp_source_ids;
+static int conf_ntp_sources_added = 0;
 
 /* Array of RefclockParameters */
 static ARR_Instance refclock_sources;
@@ -387,6 +401,8 @@ check_number_of_args(char *line, int num)
 void
 CNF_Initialise(int r, int client_only)
 {
+  char buf[10];
+
   restarted = r;
 
   hwts_interfaces = ARR_CreateInstance(sizeof (CNF_HwTsInterface));
@@ -394,13 +410,15 @@ CNF_Initialise(int r, int client_only)
   init_sources = ARR_CreateInstance(sizeof (IPAddr));
   ntp_sources = ARR_CreateInstance(sizeof (NTP_Source));
   ntp_source_dirs = ARR_CreateInstance(sizeof (char *));
-  ntp_source_ids = ARR_CreateInstance(sizeof (uint32_t));
   refclock_sources = ARR_CreateInstance(sizeof (RefclockParameters));
   broadcasts = ARR_CreateInstance(sizeof (NTP_Broadcast_Destination));
 
   ntp_restrictions = ARR_CreateInstance(sizeof (AllowDeny));
   cmd_restrictions = ARR_CreateInstance(sizeof (AllowDeny));
 
+  nts_aeads = ARR_CreateInstance(sizeof (int));
+  snprintf(buf, sizeof (buf), DEFAULT_NTS_AEADS);
+  parse_ints(buf, nts_aeads);
   nts_server_cert_files = ARR_CreateInstance(sizeof (char *));
   nts_server_key_files = ARR_CreateInstance(sizeof (char *));
   nts_trusted_certs_paths = ARR_CreateInstance(sizeof (char *));
@@ -454,13 +472,13 @@ CNF_Finalise(void)
   ARR_DestroyInstance(init_sources);
   ARR_DestroyInstance(ntp_sources);
   ARR_DestroyInstance(ntp_source_dirs);
-  ARR_DestroyInstance(ntp_source_ids);
   ARR_DestroyInstance(refclock_sources);
   ARR_DestroyInstance(broadcasts);
 
   ARR_DestroyInstance(ntp_restrictions);
   ARR_DestroyInstance(cmd_restrictions);
 
+  ARR_DestroyInstance(nts_aeads);
   ARR_DestroyInstance(nts_server_cert_files);
   ARR_DestroyInstance(nts_server_key_files);
   ARR_DestroyInstance(nts_trusted_certs_paths);
@@ -471,6 +489,7 @@ CNF_Finalise(void)
   Free(hwclock_file);
   Free(keys_file);
   Free(leapsec_tz);
+  Free(leapsec_list);
   Free(logdir);
   Free(bind_ntp_iface);
   Free(bind_acq_iface);
@@ -585,7 +604,7 @@ CNF_ParseLine(const char *filename, int number, char *line)
     parse_int(p, &cmd_port);
   } else if (!strcasecmp(command, "cmdratelimit")) {
     parse_ratelimit(p, &cmd_ratelimit_enabled, &cmd_ratelimit_interval,
-                    &cmd_ratelimit_burst, &cmd_ratelimit_leak);
+                    &cmd_ratelimit_burst, &cmd_ratelimit_leak, NULL);
   } else if (!strcasecmp(command, "combinelimit")) {
     parse_double(p, &combine_limit);
   } else if (!strcasecmp(command, "confdir")) {
@@ -620,6 +639,8 @@ CNF_ParseLine(const char *filename, int number, char *line)
     parse_leapsecmode(p);
   } else if (!strcasecmp(command, "leapsectz")) {
     parse_string(p, &leapsec_tz);
+  } else if (!strcasecmp(command, "leapseclist")) {
+    parse_string(p, &leapsec_list);
   } else if (!strcasecmp(command, "local")) {
     parse_local(p);
   } else if (!strcasecmp(command, "lock_all")) {
@@ -668,9 +689,11 @@ CNF_ParseLine(const char *filename, int number, char *line)
     no_system_cert = parse_null(p);
   } else if (!strcasecmp(command, "ntpsigndsocket")) {
     parse_string(p, &ntp_signd_socket);
+  } else if (!strcasecmp(command, "ntsaeads")) {
+    parse_ints(p, nts_aeads);
   } else if (!strcasecmp(command, "ntsratelimit")) {
     parse_ratelimit(p, &nts_ratelimit_enabled, &nts_ratelimit_interval,
-                    &nts_ratelimit_burst, &nts_ratelimit_leak);
+                    &nts_ratelimit_burst, &nts_ratelimit_leak, NULL);
   } else if (!strcasecmp(command, "ntscachedir") ||
              !strcasecmp(command, "ntsdumpdir")) {
     parse_string(p, &nts_dump_dir);
@@ -693,16 +716,18 @@ CNF_ParseLine(const char *filename, int number, char *line)
   } else if (!strcasecmp(command, "peer")) {
     parse_source(p, command, 1);
   } else if (!strcasecmp(command, "pidfile")) {
-    parse_string(p, &pidfile);
+    parse_pidfile(p);
   } else if (!strcasecmp(command, "pool")) {
     parse_source(p, command, 1);
   } else if (!strcasecmp(command, "port")) {
     parse_int(p, &ntp_port);
+  } else if (!strcasecmp(command, "ptpdomain")) {
+    parse_int(p, &ptp_domain);
   } else if (!strcasecmp(command, "ptpport")) {
     parse_int(p, &ptp_port);
   } else if (!strcasecmp(command, "ratelimit")) {
     parse_ratelimit(p, &ntp_ratelimit_enabled, &ntp_ratelimit_interval,
-                    &ntp_ratelimit_burst, &ntp_ratelimit_leak);
+                    &ntp_ratelimit_burst, &ntp_ratelimit_leak, &ntp_ratelimit_kod);
   } else if (!strcasecmp(command, "refclock")) {
     parse_refclock(p);
   } else if (!strcasecmp(command, "refresh")) {
@@ -793,6 +818,25 @@ parse_null(char *line)
 
 /* ================================================== */
 
+static int
+parse_ints(char *line, ARR_Instance array)
+{
+  char *s;
+  int v;
+
+  ARR_SetSize(array, 0);
+
+  while (*line) {
+    s = line;
+    line = CPS_SplitWord(line);
+    parse_int(s, &v);
+    ARR_AppendElement(array, &v);
+  }
+  return 1;
+}
+
+/* ================================================== */
+
 static void
 parse_source(char *line, char *type, int fatal)
 {
@@ -823,6 +867,9 @@ parse_source(char *line, char *type, int fatal)
   }
 
   source.params.name = Strdup(source.params.name);
+  source.status = NSR_NoSuchSource;
+  source.conf_id = 0;
+
   ARR_AppendElement(ntp_sources, &source);
 }
 
@@ -840,7 +887,7 @@ parse_sourcedir(char *line)
 /* ================================================== */
 
 static void
-parse_ratelimit(char *line, int *enabled, int *interval, int *burst, int *leak)
+parse_ratelimit(char *line, int *enabled, int *interval, int *burst, int *leak, int *kod)
 {
   int n, val;
   char *opt;
@@ -861,6 +908,8 @@ parse_ratelimit(char *line, int *enabled, int *interval, int *burst, int *leak)
       *burst = val;
     else if (!strcasecmp(opt, "leak"))
       *leak = val;
+    else if (!strcasecmp(opt, "kod") && kod)
+      *kod = val;
     else
       command_parse_error();
   }
@@ -1058,7 +1107,7 @@ parse_log(char *line)
 static void
 parse_local(char *line)
 {
-  if (!CPS_ParseLocal(line, &local_stratum, &local_orphan, &local_distance))
+  if (!CPS_ParseLocal(line, &local_stratum, &local_orphan, &local_distance, &local_activate))
     command_parse_error();
   enable_local = 1;
 }
@@ -1512,6 +1561,20 @@ parse_hwtimestamp(char *line)
 
 /* ================================================== */
 
+static void
+parse_pidfile(char *line)
+{
+  parse_string(line, &pidfile);
+
+  /* / disables the PID file handling */
+  if (strcmp(pidfile, "/") == 0) {
+    Free(pidfile);
+    pidfile = NULL;
+  }
+}
+
+/* ================================================== */
+
 static const char *
 get_basename(const char *path)
 {
@@ -1660,11 +1723,13 @@ compare_sources(const void *a, const void *b)
     return 1;
   if ((d = strcmp(sa->params.name, sb->params.name)) != 0)
     return d;
-  if ((d = (int)(sa->type) - (int)(sb->type)) != 0)
+  if ((d = (int)sa->type - (int)sb->type) != 0)
     return d;
-  if ((d = sa->pool - sb->pool) != 0)
+  if ((d = (int)sa->pool - (int)sb->pool) != 0)
     return d;
-  if ((d = sa->params.port - sb->params.port) != 0)
+  if ((d = (int)sa->params.family - (int)sb->params.family) != 0)
+    return d;
+  if ((d = (int)sa->params.port - (int)sb->params.port) != 0)
     return d;
   return memcmp(&sa->params.params, &sb->params.params, sizeof (sa->params.params));
 }
@@ -1676,18 +1741,17 @@ reload_source_dirs(void)
 {
   NTP_Source *prev_sources, *new_sources, *source;
   unsigned int i, j, prev_size, new_size, unresolved;
-  uint32_t *prev_ids, *new_ids;
   char buf[MAX_LINE_LENGTH];
   NSR_Status s;
-  int d;
+  int d, pass;
 
-  prev_size = ARR_GetSize(ntp_source_ids);
+  /* Ignore reload command before adding configured sources */
-  if (prev_size > 0 && ARR_GetSize(ntp_sources) != prev_size)
+  if (!conf_ntp_sources_added)
-    assert(0);
+    return;
 
-  /* Save the current sources and their configuration IDs */
+  prev_size = ARR_GetSize(ntp_sources);
-  prev_ids = MallocArray(uint32_t, prev_size);
+
-  memcpy(prev_ids, ARR_GetElements(ntp_source_ids), prev_size * sizeof (prev_ids[0]));
+  /* Save the current sources */
   prev_sources = MallocArray(NTP_Source, prev_size);
   memcpy(prev_sources, ARR_GetElements(ntp_sources), prev_size * sizeof (prev_sources[0]));
 
@@ -1705,44 +1769,45 @@ reload_source_dirs(void)
 
   new_size = ARR_GetSize(ntp_sources);
   new_sources = ARR_GetElements(ntp_sources);
-  ARR_SetSize(ntp_source_ids, new_size);
-  new_ids = ARR_GetElements(ntp_source_ids);
   unresolved = 0;
 
   LOG_SetContext(LOGC_SourceFile);
 
   qsort(new_sources, new_size, sizeof (new_sources[0]), compare_sources);
 
-  for (i = j = 0; i < prev_size || j < new_size; ) {
+  for (pass = 0; pass < 2; pass++) {
-    if (i < prev_size && j < new_size)
+    for (i = j = 0; i < prev_size || j < new_size; i += d <= 0, j += d >= 0) {
-      d = compare_sources(&prev_sources[i], &new_sources[j]);
+      if (i < prev_size && j < new_size)
-    else
+        d = compare_sources(&prev_sources[i], &new_sources[j]);
-      d = i < prev_size ? -1 : 1;
+      else
+        d = i < prev_size ? -1 : 1;
 
-    if (d < 0) {
+      /* Remove missing sources before adding others to avoid conflicts */
-      /* Remove the missing source */
+      if (pass == 0 && d < 0 && prev_sources[i].status == NSR_Success) {
-      if (prev_sources[i].params.name[0] != '\0')
+        NSR_RemoveSourcesById(prev_sources[i].conf_id);
-        NSR_RemoveSourcesById(prev_ids[i]);
+      }
-      i++;
+
-    } else if (d > 0) {
+      /* Add new sources and sources that could not be added before */
-      /* Add a newly configured source */
+      if (pass == 1 && (d > 0 || (d == 0 && prev_sources[i].status != NSR_Success))) {
-      source = &new_sources[j];
+        source = &new_sources[j];
-      s = NSR_AddSourceByName(source->params.name, source->params.port, source->pool,
+        s = NSR_AddSourceByName(source->params.name, source->params.family, source->params.port,
-                              source->type, &source->params.params, &new_ids[j]);
+                                source->pool, source->type, &source->params.params,
-
+                                &source->conf_id);
-      if (s == NSR_UnresolvedName) {
+        source->status = s;
-        unresolved++;
+
-      } else if (s != NSR_Success) {
+        if (s == NSR_UnresolvedName) {
-        LOG(LOGS_ERR, "Could not add source %s", source->params.name);
+          unresolved++;
-
+        } else if (s != NSR_Success && (d > 0 || s != prev_sources[i].status)) {
-        /* Mark the source as not present */
+          LOG(LOGS_ERR, "Could not add source %s : %s",
-        source->params.name[0] = '\0';
+              source->params.name, NSR_StatusToString(s));
+        }
+      }
+
+      /* Keep unchanged sources */
+      if (pass == 1 && d == 0) {
+        new_sources[j].status = prev_sources[i].status;
+        new_sources[j].conf_id = prev_sources[i].conf_id;
       }
-      j++;
-    } else {
-      /* Keep the existing source */
-      new_ids[j] = prev_ids[i];
-      i++, j++;
     }
   }
 
@@ -1751,7 +1816,6 @@ reload_source_dirs(void)
   for (i = 0; i < prev_size; i++)
     Free(prev_sources[i].params.name);
   Free(prev_sources);
-  Free(prev_ids);
 
   if (unresolved > 0)
     NSR_ResolveSources();
@@ -1840,15 +1904,17 @@ CNF_AddSources(void)
   for (i = 0; i < ARR_GetSize(ntp_sources); i++) {
     source = (NTP_Source *)ARR_GetElement(ntp_sources, i);
 
-    s = NSR_AddSourceByName(source->params.name, source->params.port, source->pool,
+    s = NSR_AddSourceByName(source->params.name, source->params.family, source->params.port,
-                            source->type, &source->params.params, NULL);
+                            source->pool, source->type, &source->params.params, NULL);
     if (s != NSR_Success && s != NSR_UnresolvedName)
       LOG(LOGS_ERR, "Could not add source %s", source->params.name);
 
     Free(source->params.name);
   }
 
+  /* The arrays will be used for sourcedir (re)loading */
   ARR_SetSize(ntp_sources, 0);
+  conf_ntp_sources_added = 1;
 
   reload_source_dirs();
 }
@@ -2146,12 +2212,13 @@ CNF_GetCommandPort(void) {
 /* ================================================== */
 
 int
-CNF_AllowLocalReference(int *stratum, int *orphan, double *distance)
+CNF_AllowLocalReference(int *stratum, int *orphan, double *distance, double *activate)
 {
   if (enable_local) {
     *stratum = local_stratum;
     *orphan = local_orphan;
     *distance = local_distance;
+    *activate = local_activate;
     return 1;
   } else {
     return 0;
@@ -2384,6 +2451,14 @@ CNF_GetLeapSecTimezone(void)
 
 /* ================================================== */
 
+char *
+CNF_GetLeapSecList(void)
+{
+  return leapsec_list;
+}
+
+/* ================================================== */
+
 int
 CNF_GetSchedPriority(void)
 {
@@ -2400,11 +2475,12 @@ CNF_GetLockMemory(void)
 
 /* ================================================== */
 
-int CNF_GetNTPRateLimit(int *interval, int *burst, int *leak)
+int CNF_GetNTPRateLimit(int *interval, int *burst, int *leak, int *kod)
 {
   *interval = ntp_ratelimit_interval;
   *burst = ntp_ratelimit_burst;
   *leak = ntp_ratelimit_leak;
+  *kod = ntp_ratelimit_kod;
   return ntp_ratelimit_enabled;
 }
 
@@ -2538,6 +2614,14 @@ CNF_GetPtpPort(void)
 
 /* ================================================== */
 
+int
+CNF_GetPtpDomain(void)
+{
+  return ptp_domain;
+}
+
+/* ================================================== */
+
 int
 CNF_GetRefresh(void)
 {
@@ -2546,6 +2630,14 @@ CNF_GetRefresh(void)
 
 /* ================================================== */
 
+ARR_Instance
+CNF_GetNtsAeads(void)
+{
+  return nts_aeads;
+}
+
+/* ================================================== */
+
 char *
 CNF_GetNtsDumpDir(void)
 {

conf.h

@@ -29,6 +29,7 @@
 #define GOT_CONF_H
 
 #include "addressing.h"
+#include "array.h"
 #include "reference.h"
 #include "sources.h"
 
@@ -91,6 +92,7 @@ extern char *CNF_GetNtpSigndSocket(void);
 extern char *CNF_GetPidFile(void);
 extern REF_LeapMode CNF_GetLeapSecMode(void);
 extern char *CNF_GetLeapSecTimezone(void);
+extern char *CNF_GetLeapSecList(void);
 
 /* Value returned in ppm, as read from file */
 extern double CNF_GetMaxUpdateSkew(void);
@@ -107,14 +109,14 @@ extern double CNF_GetReselectDistance(void);
 extern double CNF_GetStratumWeight(void);
 extern double CNF_GetCombineLimit(void);
 
-extern int CNF_AllowLocalReference(int *stratum, int *orphan, double *distance);
+extern int CNF_AllowLocalReference(int *stratum, int *orphan, double *distance, double *activate);
 
 extern void CNF_SetupAccessRestrictions(void);
 
 extern int CNF_GetSchedPriority(void);
 extern int CNF_GetLockMemory(void);
 
-extern int CNF_GetNTPRateLimit(int *interval, int *burst, int *leak);
+extern int CNF_GetNTPRateLimit(int *interval, int *burst, int *leak, int *kod);
 extern int CNF_GetNtsRateLimit(int *interval, int *burst, int *leak);
 extern int CNF_GetCommandRateLimit(int *interval, int *burst, int *leak);
 extern void CNF_GetSmooth(double *max_freq, double *max_wander, int *leap_only);
@@ -158,9 +160,11 @@ extern int CNF_GetHwTsInterface(unsigned int index, CNF_HwTsInterface **iface);
 extern double CNF_GetHwTsTimeout(void);
 
 extern int CNF_GetPtpPort(void);
+extern int CNF_GetPtpDomain(void);
 
 extern int CNF_GetRefresh(void);
 
+extern ARR_Instance CNF_GetNtsAeads(void);
 extern char *CNF_GetNtsDumpDir(void);
 extern char *CNF_GetNtsNtpServer(void);
 extern int CNF_GetNtsServerCertAndKeyFiles(const char ***certs, const char ***keys);

configure

@@ -5,7 +5,7 @@
 #
 # Copyright (C) Richard P. Curnow  1997-2003
 # Copyright (C) Bryan Christianson  2016
-# Copyright (C) Miroslav Lichvar  2009, 2012-2021
+# Copyright (C) Miroslav Lichvar  2009, 2012-2022
 # Copyright (C) Stefan R. Filipek  2019
 #
 # =======================================================================
@@ -111,10 +111,10 @@ For better control, use the options below.
   --without-editline     Don't use editline even if it is available
   --disable-sechash      Disable support for hashes other than MD5
   --without-nettle       Don't use nettle even if it is available
+  --without-gnutls       Don't use gnutls even if it is available
   --without-nss          Don't use NSS even if it is available
   --without-tomcrypt     Don't use libtomcrypt even if it is available
   --disable-nts          Disable NTS support
-  --without-gnutls       Don't use gnutls even if it is available
   --disable-cmdmon       Disable command and monitoring support
   --disable-ntp          Disable NTP support
   --disable-refclock     Disable reference clock support
@@ -570,6 +570,13 @@ if [ "x$MYCFLAGS" = "x" ]; then
   fi
 fi
 
+TESTCFLAGS="-fwrapv"
+if test_code '-fwrapv' '' "$TESTCFLAGS" '' ''; then
+  GETDATE_CFLAGS="-fwrapv"
+else
+  GETDATE_CFLAGS=""
+fi
+
 if [ "x$MYCC" = "xgcc" ] || [ "x$MYCC" = "xclang" ]; then
   MYCFLAGS="$MYCFLAGS -Wmissing-prototypes -Wall"
 fi
@@ -919,6 +926,28 @@ if [ $feat_sechash = "1" ] && [ "x$HASH_LINK" = "x" ]  && [ $try_nettle = "1" ];
   fi
 fi
 
+if [ $feat_sechash = "1" ] && [ "x$HASH_LINK" = "x" ] && [ $try_gnutls = "1" ]; then
+  test_cflags="`pkg_config --cflags gnutls`"
+  test_link="`pkg_config --libs gnutls`"
+  if test_code 'gnutls' 'gnutls/crypto.h' \
+    "$test_cflags" "$test_link" '
+      return gnutls_hash((void *)1, (void *)2, 1);'
+  then
+    HASH_OBJ="hash_gnutls.o"
+    HASH_LINK="$test_link"
+    MYCPPFLAGS="$MYCPPFLAGS $test_cflags"
+    add_def FEAT_SECHASH
+
+    if test_code 'CMAC in gnutls' 'gnutls/crypto.h' "$test_cflags" "$test_link" \
+      'return gnutls_hmac_init((void *)1, GNUTLS_MAC_AES_CMAC_128, (void *)2, 0);'
+    then
+      add_def HAVE_CMAC
+      EXTRA_OBJECTS="$EXTRA_OBJECTS cmac_gnutls.o"
+      EXTRA_CLI_OBJECTS="$EXTRA_CLI_OBJECTS cmac_gnutls.o"
+    fi
+  fi
+fi
+
 if [ $feat_sechash = "1" ] && [ "x$HASH_LINK" = "x" ]  && [ $try_nss = "1" ]; then
   test_cflags="`pkg_config --cflags nss`"
   test_link="`pkg_config --libs-only-L nss` -lfreebl3 -lnssutil3"
@@ -944,28 +973,6 @@ if [ $feat_sechash = "1" ] && [ "x$HASH_LINK" = "x" ] && [ $try_tomcrypt = "1" ]
   fi
 fi
 
-if [ $feat_sechash = "1" ] && [ "x$HASH_LINK" = "x" ] && [ $try_gnutls = "1" ]; then
-  test_cflags="`pkg_config --cflags gnutls`"
-  test_link="`pkg_config --libs gnutls`"
-  if test_code 'gnutls' 'gnutls/crypto.h' \
-    "$test_cflags" "$test_link" '
-      return gnutls_hash((void *)1, (void *)2, 1);'
-  then
-    HASH_OBJ="hash_gnutls.o"
-    HASH_LINK="$test_link"
-    MYCPPFLAGS="$MYCPPFLAGS $test_cflags"
-    add_def FEAT_SECHASH
-
-    if test_code 'CMAC in gnutls' 'gnutls/crypto.h' "$test_cflags" "$test_link" \
-      'return gnutls_hmac_init((void *)1, GNUTLS_MAC_AES_CMAC_128, (void *)2, 0);'
-    then
-      add_def HAVE_CMAC
-      EXTRA_OBJECTS="$EXTRA_OBJECTS cmac_gnutls.o"
-      EXTRA_CLI_OBJECTS="$EXTRA_CLI_OBJECTS cmac_gnutls.o"
-    fi
-  fi
-fi
-
 EXTRA_OBJECTS="$EXTRA_OBJECTS $HASH_OBJ"
 EXTRA_CLI_OBJECTS="$EXTRA_CLI_OBJECTS $HASH_OBJ"
 LIBS="$LIBS $HASH_LINK"
@@ -984,7 +991,7 @@ if [ $feat_ntp = "1" ] && [ $feat_nts = "1" ] && [ $try_gnutls = "1" ]; then
         gnutls_priority_init2((void *)1, "", NULL, GNUTLS_PRIORITY_INIT_DEF_APPEND) +
         gnutls_prf_rfc5705((void *)1, 0, "", 0, "", 16, (void *)2);'
   then
-    if test_code 'AES-SIV-CMAC in nettle' \
+    if [ $try_nettle = "1" ] && test_code 'AES-SIV-CMAC in nettle' \
       'nettle/siv-cmac.h' "" "$LIBS" \
       'siv_cmac_aes128_set_key((void *)1, (void *)2);'
     then
@@ -1005,6 +1012,13 @@ if [ $feat_ntp = "1" ] && [ $feat_nts = "1" ] && [ $try_gnutls = "1" ]; then
       then
         EXTRA_OBJECTS="$EXTRA_OBJECTS siv_gnutls.o"
         add_def HAVE_SIV
+        if [ $try_aes_gcm_siv = "1" ] && test_code 'AES-GCM-SIV in gnutls' \
+          'gnutls/crypto.h' "$test_cflags" "$test_link $LIBS" '
+            return gnutls_aead_cipher_init((void *)1, GNUTLS_CIPHER_AES_128_SIV_GCM,
+                                           (void *)2);'
+        then
+          add_def HAVE_GNUTLS_SIV_GCM
+        fi
         if test_code 'gnutls_aead_cipher_set_key()' 'gnutls/crypto.h' \
           "$test_cflags" "$test_link $LIBS" '
             return gnutls_aead_cipher_set_key((void *)1, (void *)2);'
@@ -1122,6 +1136,7 @@ do
           s%@CFLAGS@%${MYCFLAGS}%;\
           s%@CPPFLAGS@%${MYCPPFLAGS}%;\
           s%@LDFLAGS@%${MYLDFLAGS}%;\
+          s%@GETDATE_CFLAGS@%${GETDATE_CFLAGS}%;\
           s%@LIBS@%${LIBS}%;\
           s%@EXTRA_LIBS@%${EXTRA_LIBS}%;\
           s%@EXTRA_CLI_LIBS@%${EXTRA_CLI_LIBS}%;\

contrib/bryan_christianson_1/README.txt

@@ -60,8 +60,8 @@ Support files
 Dates and sizes may differ
 -rw-r--r--  1 yourname  staff  2084  4 Aug 22:54 README.txt
 -rwxr-xr-x  1 yourname  staff   676  4 Aug 21:18 chronylogrotate.sh
--rw-r--r--  1 yourname  staff   543 18 Jul 20:10 org.tuxfamily.chronyc.plist
+-rw-r--r--  1 yourname  staff   543 18 Jul 20:10 org.chrony-project.chronyc.plist
--rw-r--r--  1 yourname  staff   511 19 Jun 18:30 org.tuxfamily.chronyd.plist
+-rw-r--r--  1 yourname  staff   511 19 Jun 18:30 org.chrony-project.chronyd.plist
 
 If you have used chrony support directories other than those suggested, you
 will need to edit each file and make the appropriate changes.
@@ -83,21 +83,21 @@ sudo chmod +x /usr/local/bin/chronylogrotate.sh
 sudo chown root:wheel /usr/local/bin/chronylogrotate.sh
 
 
-2. org.tuxfamily.chronyc.plist
+2. org.chrony-project.chronyc.plist
 This file is the launchd plist that runs logrotation each day. You may
 wish to edit this file to change the time of day at which the rotation
 will run, currently 04:05 am
 
-sudo cp org.tuxfamily.chronyc.plist /Library/LaunchDaemons
+sudo cp org.chrony-project.chronyc.plist /Library/LaunchDaemons
-sudo chown root:wheel /Library/LaunchDaemons/org.tuxfamily.chronyc.plist
+sudo chown root:wheel /Library/LaunchDaemons/org.chrony-project.chronyc.plist
-sudo chmod 0644 /Library/LaunchDaemons/org.tuxfamily.chronyc.plist
+sudo chmod 0644 /Library/LaunchDaemons/org.chrony-project.chronyc.plist
-sudo launchctl load -w /Library/LaunchDaemons/org.tuxfamily.chronyc.plist
+sudo launchctl load -w /Library/LaunchDaemons/org.chrony-project.chronyc.plist
 
 
-3. org.tuxfamily.chronyd.plist
+3. org.chrony-project.chronyd.plist
 This file is the launchd plist that runs chronyd when the Macintosh starts.
 
-sudo cp org.tuxfamily.chronyd.plist /Library/LaunchDaemons
+sudo cp org.chrony-project.chronyd.plist /Library/LaunchDaemons
-sudo chown root:wheel /Library/LaunchDaemons/org.tuxfamily.chronyd.plist
+sudo chown root:wheel /Library/LaunchDaemons/org.chrony-project.chronyd.plist
-sudo chmod 0644 /Library/LaunchDaemons/org.tuxfamily.chronyd.plist
+sudo chmod 0644 /Library/LaunchDaemons/org.chrony-project.chronyd.plist
-sudo launchctl load -w /Library/LaunchDaemons/org.tuxfamily.chronyd.plist
+sudo launchctl load -w /Library/LaunchDaemons/org.chrony-project.chronyd.plist

contrib/bryan_christianson_1/org.chrony-project.chronyc.plist

@@ -3,7 +3,7 @@
 <plist version="1.0">
 <dict>
 	<key>Label</key>
-	<string>org.tuxfamily.logrotate</string>
+	<string>org.chrony-project.logrotate</string>
 	<key>KeepAlive</key>
 	<false/>
 	<key>ProgramArguments</key>

contrib/bryan_christianson_1/org.chrony-project.chronyd.plist

@@ -3,7 +3,7 @@
 <plist version="1.0">
 <dict>
 	<key>Label</key>
-	<string>org.tuxfamily.chronyd</string>
+	<string>org.chrony-project.chronyd</string>
 	<key>Program</key>
 	<string>/usr/local/sbin/chronyd</string>
 	<key>ProgramArguments</key>

doc/chrony.conf.adoc

@@ -3,7 +3,7 @@
 // Copyright (C) Richard P. Curnow  1997-2003
 // Copyright (C) Stephen Wadeley  2016
 // Copyright (C) Bryan Christianson  2017
-// Copyright (C) Miroslav Lichvar  2009-2022
+// Copyright (C) Miroslav Lichvar  2009-2024
 //
 // 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
@@ -126,6 +126,15 @@ mechanism. Unlike with the *key* option, the server and client do not need to
 share a key in a key file. NTS has a Key Establishment (NTS-KE) protocol using
 the Transport Layer Security (TLS) protocol to get the keys and cookies
 required by NTS for authentication of NTP packets.
++
+With this option, the hostname specified in the server or pool directive is the
+NTS-KE server or pool of NTS-KE servers respectively. The NTP server usually
+runs on the same host, but it can be separated from the NTS-KE server (the
+hostname or address of the NTP server is provided to the client by the NTS-KE
+server).
++
+The NTS-KE server can be specified by IP address if it is included in the
+server's certificate as a Subject Alternative Name (SAN).
 *certset* _ID_:::
 This option specifies which set of trusted certificates should be used to verify
 the server's certificate when the *nts* option is enabled. Sets of certificates
@@ -220,7 +229,7 @@ when disconnecting the network link. (It will still be necessary to use the
 <<chronyc.adoc#online,*online*>> command when the link has been established, to
 enable measurements to start.)
 *prefer*:::
-Prefer this source over sources without the *prefer* option.
+Prefer this source over other selectable sources without the *prefer* option.
 *noselect*:::
 Never select this source. This is particularly useful for monitoring.
 *trust*:::
@@ -322,16 +331,33 @@ server implementations do not respond to requests containing an unknown
 extension field (*chronyd* as a server responded to such requests since
 version 2.0).
 +
-The following extension field can be enabled by this option:
+This option can be used multiple times to enable multiple extension fields.
++
+The following extension fields are supported:
 +
 _F323_::::
-This is an experimental extension field for some improvements that were
+An experimental extension field to enable several improvements that were
 proposed for the next version of the NTP protocol (NTPv5). The field contains
 root delay and dispersion in higher resolution and a monotonic receive
-timestamp, which enables a frequency transfer between the server and client. It
+timestamp, which enables a frequency transfer between the server and client to
-can significantly improve stability of the synchronization. Generally, it
+significantly improve stability of the synchronisation. This field should be
-should be expected to work only between servers and clients running the same
+enabled only for servers known to be running *chronyd* version 4.2 or later.
-version of *chronyd*.
+_F324_::::
+An experimental extension field to enable the use of the Precision Time
+Protocol (PTP) correction field in NTP-over-PTP messages updated by one-step
+end-to-end transparent clocks in network switches and routers to significantly
+improve accuracy and stability of the synchronisation. NTP-over-PTP can be
+enabled by the <<ptpport,*ptpport*>> directive and setting the *port* option to
+the PTP port. The corrections are applied only to NTP measurements with HW
+timestamps (enabled by the <<hwtimestamp,*hwtimestamp*>> directive). This
+field should be enabled only for servers known to be running *chronyd* version
+4.5 or later.
+*ipv4*:::
+*ipv6*:::
+These options force *chronyd* to use only IPv4 or IPv6 addresses respectively
+for this source. They do not override the *-4* or *-6* option on the *chronyd*
+command line.
+
 {blank}:::
 
 [[pool]]*pool* _name_ [_option_]...::
@@ -418,7 +444,7 @@ error. *chronyd* then enters its normal operating mode.
 An example of the use of the directive is:
 +
 ----
-initstepslew 30 foo.example.net bar.example.net baz.example.net
+initstepslew 30 ntp1.example.net ntp2.example.net ntp3.example.net
 ----
 +
 where 3 NTP servers are used to make the measurement. The _30_ indicates that
@@ -644,7 +670,7 @@ default is 64. With drivers that perform their own polling (PPS, PHC, SHM), the
 maximum value is adjusted to the number of driver polls per source poll, i.e.
 2^(_poll_ - _dpoll_).
 *prefer*:::
-Prefer this source over sources without the prefer option.
+Prefer this source over other selectable sources without the *prefer* option.
 *noselect*:::
 Never select this source. This is useful for monitoring or with sources which
 are not very accurate, but are locked with a PPS refclock.
@@ -663,9 +689,10 @@ trusted and required source.
 *tai*:::
 This option indicates that the reference clock keeps time in TAI instead of UTC
 and that *chronyd* should correct its offset by the current TAI-UTC offset. The
-<<leapsectz,*leapsectz*>> directive must be used with this option and the
+<<leapsectz,*leapsectz*>> or <<leapseclist,*leapseclist*>> directive must be
-database must be kept up to date in order for this correction to work as
+used with this option and the database must be kept up to date in order for
-expected. This option does not make sense with PPS refclocks.
+this correction to work as expected. This option does not make sense with PPS
+refclocks.
 *local*:::
 This option specifies that the reference clock is an unsynchronised clock which
 is more stable than the system clock (e.g. TCXO, OCXO, or atomic clock) and
@@ -806,6 +833,34 @@ changes in the frequency and offset of the clock. The offsets in the
 <<chronyc.adoc#sourcestats,*sourcestats*>> reports (and the _tracking.log_ and
 _statistics.log_ files) may be smaller than the actual offsets.
 
+[[ntsaeads1]]*ntsaeads* _ID_...::
+This directive specifies a list of IDs of Authenticated Encryption with
+Associated Data (AEAD) algorithms enabled for NTS authentication of NTP
+messages. The algorithms are specified in decreasing order of priority.
+Algorithms that are not supported by the installed version of the crypto
+library (Nettle, GnuTLS) are ignored.
++
+The following IDs are supported:
++
+* 15: AES-SIV-CMAC-256
+* 30: AES-128-GCM-SIV
+{blank}::
++
+The default list of IDs is _30 15_. AES-128-GCM-SIV is prefered over
+AES-SIV-CMAC-256 for shorter keys, which makes NTS cookies shorter and improves
+reliability of NTS in networks that block or limit rate of longer NTP messages.
++
+The ID of the used algorithm is reported for each server by the
+<<chronyc.adoc#authdata,*authdata*>> command.
++
+An example of the directive is:
++
+----
+ntsaeads 15
+----
++
+This list is used also by the <<ntsaeads2,NTS server>>.
+
 [[ntsdumpdir1]]*ntsdumpdir* _directory_::
 This directive specifies a directory for the client to save NTS cookies it
 received from the server in order to avoid making an NTS-KE request when
@@ -833,9 +888,10 @@ sources using NTS, otherwise the source with a longer polling interval will
 refresh the keys on each poll and no NTP packets will be exchanged.
 
 [[ntstrustedcerts]]*ntstrustedcerts* [_set-ID_] _file_|_directory_::
-This directive specifies a file or directory containing certificates (in the
+This directive specifies a file or directory containing trusted certificates
-PEM format) of trusted certificate authorities (CA) which can be used to
+(in the PEM format) which are needed to verify certificates of NTS-KE servers,
-verify certificates of NTS servers.
+e.g. certificates of trusted certificate authorities (CA) or self-signed
+certificates of the servers.
 +
 The optional _set-ID_ argument is a number in the range 0 through 2^32-1, which
 selects the set of certificates where certificates from the specified file
@@ -855,10 +911,10 @@ they change (e.g. after a renewal).
 An example is:
 +
 ----
-ntstrustedcerts /etc/pki/nts/foo.crt
+ntstrustedcerts /etc/pki/nts/ca1.example.net.crt
-ntstrustedcerts 1 /etc/pki/nts/bar.crt
+ntstrustedcerts 1 /etc/pki/nts/ca2.example.net.crt
-ntstrustedcerts 1 /etc/pki/nts/baz.crt
+ntstrustedcerts 1 /etc/pki/nts/ca3.example.net.crt
-ntstrustedcerts 2 /etc/pki/nts/qux.crt
+ntstrustedcerts 2 /etc/pki/nts/ntp2.example.net.crt
 ----
 
 [[nosystemcert]]*nosystemcert*::
@@ -955,9 +1011,9 @@ before 4.0.
 As an example, the following configuration using the default *mix* mode:
 +
 ----
-server foo.example.net nts
+server ntp1.example.net nts
-server bar.example.net nts
+server ntp2.example.net nts
-server baz.example.net
+server ntp3.example.net
 refclock SOCK /var/run/chrony.ttyS0.sock
 ----
 +
@@ -965,9 +1021,9 @@ is equivalent to the following configuration using the *ignore* mode:
 +
 ----
 authselectmode ignore
-server foo.example.net nts require trust
+server ntp1.example.net nts require trust
-server bar.example.net nts require trust
+server ntp2.example.net nts require trust
-server baz.example.net
+server ntp3.example.net
 refclock /var/run/chrony.ttyS0.sock require trust
 ----
 
@@ -1251,6 +1307,19 @@ $ TZ=right/UTC date -d 'Dec 31 2008 23:59:60'
 Wed Dec 31 23:59:60 UTC 2008
 ----
 
+[[leapseclist]]*leapseclist* _file_::
+This directive specifies the path to a file containing a list of leap seconds
+and TAI-UTC offsets in NIST/IERS format. It is recommended to use
+the file _leap-seconds.list_ usually included with the system timezone
+database. The behaviour of this directive is otherwise equivalent to
+<<leapsectz,*leapsectz*>>.
++
+An example of this directive is:
++
+----
+leapseclist /usr/share/zoneinfo/leap-seconds.list
+----
+
 [[makestep]]*makestep* _threshold_ _limit_::
 Normally *chronyd* will cause the system to gradually correct any time offset,
 by slowing down or speeding up the clock as required. In certain situations,
@@ -1643,6 +1712,14 @@ The current root distance can be calculated from root delay and root dispersion
 ----
 distance = delay / 2 + dispersion
 ----
+*activate* _distance_:::
+This option sets an activating root distance for the local reference. The
+local reference will not be used until the root distance drops below the
+configured value for the first time. This can be used to prevent the local
+reference from being activated on a server which has never been synchronised
+with an upstream server. The default value of 0.0 causes no activating
+distance to be used, such that the local reference is always eligible for
+activation.
 *orphan*:::
 This option enables a special '`orphan`' mode, where sources with stratum equal
 to the local _stratum_ are assumed to not serve real time. They are ignored
@@ -1665,7 +1742,7 @@ The *orphan* mode is compatible with the *ntpd*'s orphan mode (enabled by the
 An example of the directive is:
 +
 ----
-local stratum 10 orphan distance 0.1
+local stratum 10 orphan distance 0.1 activate 0.5
 ----
 
 [[ntpsigndsocket]]*ntpsigndsocket* _directory_::
@@ -1730,6 +1807,43 @@ per process that the NTS server will accept. The default value is 100. The
 maximum practical value is half of the system *FD_SETSIZE* constant (usually
 1024).
 
+[[ntsaeads2]]*ntsaeads* _ID_...::
+This directive specifies a list of IDs of Authenticated Encryption with
+Associated Data (AEAD) algorithms enabled for NTS authentication of NTP
+messages. *chronyd* as a server uses the first enabled algorithm from the list
+provided by the client. Algorithms that are not supported by the installed
+version of the crypto library (Nettle, GnuTLS) are ignored.
++
+The following IDs are supported:
++
+* 15: AES-SIV-CMAC-256
+* 30: AES-128-GCM-SIV
+{blank}::
++
+The default list of IDs is _30 15_. AES-128-GCM-SIV is prefered over
+AES-SIV-CMAC-256 for shorter keys, which makes NTS cookies shorter and improves
+reliability of NTS in networks that block or limit rate of longer NTP messages.
++
+An example of the directive is:
++
+----
+ntsaeads 15
+----
++
+This list is used also by the <<ntsaeads1,NTS client>>.
++
+Note the the NTS specification (RFC 8915) requires servers to support
+AES-SIV-CMAC-256, i.e. 15 should be always included in the specified list.
++
+The AES-128-GCM-SIV keys used by *chronyd* do not comply to RFC 8915 for
+compatibility with older *chrony* clients unless the use of compliant keys is
+negotiated with an
+https://chrony-project.org/doc/spec/nts-compliant-128gcm.html[NTS-KE record].
+Support for this record was added in version 4.6.1. As a client, *chronyd* can
+interoperate with a server that uses compliant keys, but does not support the
+negotiation, if it responds to incorrectly authenticated requests with an NTS
+NAK.
+
 [[ntsdumpdir2]]*ntsdumpdir* _directory_::
 This directive specifies a directory where *chronyd* operating as an NTS server
 can save the keys which encrypt NTS cookies provided to clients. The keys are
@@ -1829,6 +1943,14 @@ source address from completely blocking responses to that address. The leak
 rate is defined as a power of 1/2 and it is 2 by default, i.e. on average at
 least every fourth request has a response. The minimum value is 1 and the
 maximum value is 4.
+*kod* _rate_:::
+This option sets the rate at which Kiss-o'-Death (KoD) RATE responses are
+randomly sent when the limits specified by the *interval* and *burst* options
+are exceeded. It is an additional stream of responses to the *leak* option. A
+KoD RATE response is a request for the client to reduce its polling rate. Few
+implementations actually support it. The rate is defined as a power of 1/2. The
+default value is 0, which means disabled. The minimum value is 0 and the
+maximum value is 4.
 {blank}::
 +
 An example use of the directive is:
@@ -1844,7 +1966,7 @@ packets, by up to 75% (with default *leak* of 2).
 [[ntsratelimit]]*ntsratelimit* [_option_]...::
 This directive enables rate limiting of NTS-KE requests. It is similar to the
 <<ratelimit,*ratelimit*>> directive, except the default interval is 6
-(1 connection per 64 seconds).
+(1 connection per 64 seconds) and the *kod* option is not supported.
 +
 An example of the use of the directive is:
 +
@@ -1976,8 +2098,9 @@ all* directive.
 [[cmdport]]*cmdport* _port_::
 The *cmdport* directive allows the port that is used for run-time monitoring
 (via the *chronyc* program) to be altered from its default (323). If set to 0,
-*chronyd* will not open the port, this is useful to disable *chronyc*
+*chronyd* will not open the port, which disables remote *chronyc* access (with
-access from the Internet. (It does not disable the Unix domain command socket.)
+a non-default *bindcmdaddress*) and local access for unprivileged users. It
+does not disable the Unix domain command socket.
 +
 An example shows the syntax:
 +
@@ -1986,13 +2109,13 @@ cmdport 257
 ----
 +
 This would make *chronyd* use UDP 257 as its command port. (*chronyc* would
-need to be run with the *-p 257* switch to inter-operate correctly.)
+need to be run with the *-p 257* option to inter-operate correctly.)
 
 [[cmdratelimit]]*cmdratelimit* [_option_]...::
 This directive enables response rate limiting for command packets. It is
 similar to the <<ratelimit,*ratelimit*>> directive, except responses to
-localhost are never limited and the default interval is -4 (16 packets per
+localhost are never limited, the default interval is -4 (16 packets per
-second).
+second), and the *kod* option is not supported.
 +
 An example of the use of the directive is:
 +
@@ -2130,8 +2253,8 @@ from the example line above):
 . Results of the *maxdelay*, *maxdelayratio*, and *maxdelaydevratio* (or
   *maxdelayquant*) tests, and a test for synchronisation loop (1=pass,
   0=fail). The first test from these four also checks the server precision,
-  response time, and whether an interleaved response is acceptable for
+  response time, validity of the measured offset, and whether an interleaved
-  synchronisation. [1111]
+  response is acceptable for synchronisation. [1111]
 . Local poll [10]
 . Remote poll [10]
 . '`Score`' (an internal score within each polling level used to decide when to
@@ -2698,7 +2821,11 @@ source is specified in the configuration file with a key shorter than 80 bits.
 +
 The recommended key types are AES ciphers and SHA3 hash functions. MD5 should
 be avoided unless no other type is supported on the server and client, or
-peers.
+peers. A major weakness of MD5 for the NTP MAC is a length extension attack,
+where a man-in-the-middle attacker can add arbitrary extension fields to the
+NTP message and update the MAC to pass the verification of the extended
+message. The *extfield* option (enabling processing of the specified extension
+field) should not be used for NTP sources authenticated with an MD5 key.
 +
 The <<chronyc.adoc#keygen,*keygen*>> command of *chronyc* can be used to
 generate random keys for the key file. By default, it generates 160-bit MD5 or
@@ -2723,33 +2850,43 @@ e.g.:
 ----
 pidfile /run/chronyd.pid
 ----
++
+Setting this directive to _/_ disables writing and checking of the PID file.
 
 [[ptpport]]*ptpport* _port_::
 The *ptpport* directive enables *chronyd* to send and receive NTP messages
 contained in PTP event messages (NTP-over-PTP) to enable hardware timestamping
 on NICs which cannot timestamp NTP packets, but can timestamp unicast PTP
-packets. The port recognized by the NICs is 319 (PTP event port). The default
+packets, and also use corrections provided by PTP one-step end-to-end
-value is 0 (disabled).
+transparent clocks in network switches and routers. The port recognized by the
+NICs and PTP transparent clocks is 319 (PTP event port). The default value is 0
+(disabled).
 +
 The NTP-over-PTP support is experimental. The protocol and configuration can
-change in future. It should be used only in local networks and expected to work
+change in future. It should be used only in local networks.
-only between servers and clients running the same version of *chronyd*.
 +
 The PTP port will be open even if *chronyd* is not configured to operate as a
 server or client. The directive does not change the default protocol of
 specified NTP sources. Each NTP source that should use NTP-over-PTP needs to
 be specified with the *port* option set to the PTP port. To actually enable
 hardware timestamping on NICs which can timestamp PTP packets only, the
-*rxfilter* option of the *hwtimestamp* directive needs to be set to _ptp_.
+*rxfilter* option of the *hwtimestamp* directive needs to be set to _ptp_. The
+extension field _F324_ needs to be enabled to use the corrections provided by
+the PTP transparent clocks.
 +
 An example of client configuration is:
 +
 ----
-server foo.example.net minpoll 0 maxpoll 0 xleave port 319
+server ntp1.example.net minpoll 0 maxpoll 0 xleave port 319 extfield F324
 hwtimestamp * rxfilter ptp
 ptpport 319
 ----
 
+[[ptpdomain]]*ptpdomain* _domain_::
+The *ptpdomain* directive sets the PTP domain number of transmitted and
+accepted NTP-over-PTP messages. Messages from other domains are ignored.
+The default is 123, the minimum is 0, and the maximum is 255.
+
 [[sched_priority]]*sched_priority* _priority_::
 On Linux, FreeBSD, NetBSD, and illumos, the *sched_priority* directive will
 select the SCHED_FIFO real-time scheduler at the specified priority (which must
@@ -2806,13 +2943,13 @@ the following methods:
   facilities.
 * Use public servers from the https://www.pool.ntp.org/[pool.ntp.org] project.
 
-Assuming that your NTP servers are called _foo.example.net_, _bar.example.net_
+Assuming that your NTP servers are called _ntp1.example.net_, _ntp2.example.net_
-and _baz.example.net_, your _chrony.conf_ file could contain as a minimum:
+and _ntp3.example.net_, your _chrony.conf_ file could contain as a minimum:
 
 ----
-server foo.example.net
+server ntp1.example.net
-server bar.example.net
+server ntp2.example.net
-server baz.example.net
+server ntp3.example.net
 ----
 
 However, you will probably want to include some of the other directives. The
@@ -2823,9 +2960,9 @@ synchronisation. The smallest useful configuration file would look something
 like:
 
 ----
-server foo.example.net iburst
+server ntp1.example.net iburst
-server bar.example.net iburst
+server ntp2.example.net iburst
-server baz.example.net iburst
+server ntp3.example.net iburst
 driftfile @CHRONYVARDIR@/drift
 makestep 1.0 3
 rtcsync
@@ -2849,9 +2986,9 @@ option will enable a secure synchronisation to the servers. The configuration
 file could look like:
 
 ----
-server foo.example.net iburst nts
+server ntp1.example.net iburst nts
-server bar.example.net iburst nts
+server ntp2.example.net iburst nts
-server baz.example.net iburst nts
+server ntp3.example.net iburst nts
 driftfile @CHRONYVARDIR@/drift
 makestep 1.0 3
 rtcsync
@@ -2865,14 +3002,14 @@ additional configuration to tell *chronyd* when the connection goes up and
 down. This saves the program from continuously trying to poll the servers when
 they are inaccessible.
 
-Again, assuming that your NTP servers are called _foo.example.net_,
+Again, assuming that your NTP servers are called _ntp1.example.net_,
-_bar.example.net_ and _baz.example.net_, your _chrony.conf_ file would now
+_ntp2.example.net_ and _ntp3.example.net_, your _chrony.conf_ file would now
 contain:
 
 ----
-server foo.example.net offline
+server ntp1.example.net offline
-server bar.example.net offline
+server ntp2.example.net offline
-server baz.example.net offline
+server ntp3.example.net offline
 driftfile @CHRONYVARDIR@/drift
 makestep 1.0 3
 rtcsync
@@ -3056,9 +3193,9 @@ configuration files are shown.
 For the _chrony.conf_ file, the following can be used as an example.
 
 ----
-server foo.example.net maxdelay 0.4 offline
+server ntp1.example.net maxdelay 0.4 offline
-server bar.example.net maxdelay 0.4 offline
+server ntp2.example.net maxdelay 0.4 offline
-server baz.example.net maxdelay 0.4 offline
+server ntp3.example.net maxdelay 0.4 offline
 logdir /var/log/chrony
 log statistics measurements tracking
 driftfile @CHRONYVARDIR@/drift
@@ -3117,10 +3254,10 @@ configuration).
 The configuration file could look like:
 
 ----
-server foo.example.net iburst
+server ntp1.example.net iburst
-server bar.example.net iburst
+server ntp2.example.net iburst
-server baz.example.net iburst
+server ntp3.example.net iburst
-server qux.example.net iburst
+server ntp4.example.net iburst
 makestep 1.0 3
 rtcsync
 allow
@@ -3137,7 +3274,7 @@ dumpdir @CHRONYRUNDIR@
 == BUGS
 
 For instructions on how to report bugs, please visit
-https://chrony.tuxfamily.org/.
+https://chrony-project.org/.
 
 == AUTHORS
 

doc/chronyc.adoc

@@ -2,7 +2,7 @@
 //
 // Copyright (C) Richard P. Curnow  1997-2003
 // Copyright (C) Stephen Wadeley  2016
-// Copyright (C) Miroslav Lichvar  2009-2017, 2019-2022
+// Copyright (C) Miroslav Lichvar  2009-2017, 2019-2024
 //
 // 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
@@ -144,7 +144,7 @@ The *tracking* command displays parameters about the system's clock
 performance. An example of the output is shown below.
 +
 ----
-Reference ID    : CB00710F (foo.example.net)
+Reference ID    : CB00710F (ntp1.example.net)
 Stratum         : 3
 Ref time (UTC)  : Fri Jan 27 09:49:17 2017
 System time     : 0.000006523 seconds slow of NTP time
@@ -178,7 +178,7 @@ with an IPv4 address.
 *Stratum*:::
 The stratum indicates how many hops away from a computer with an attached
 reference clock we are. Such a computer is a stratum-1 computer, so the
-computer in the example is two hops away (i.e. _foo.example.net_ is a
+computer in the example is two hops away (i.e. _ntp1.example.net_ is a
 stratum-2 and is synchronised from a stratum-1).
 *Ref time*:::
 This is the time (UTC) at which the last measurement from the reference
@@ -321,8 +321,8 @@ extra caption lines are shown as a reminder of the meanings of the columns.
 MS Name/IP address         Stratum Poll Reach LastRx Last sample
 ===============================================================================
 #* GPS0                          0   4   377    11   -479ns[ -621ns] +/-  134ns
-^? foo.example.net               2   6   377    23   -923us[ -924us] +/-   43ms
+^? ntp1.example.net              2   6   377    23   -923us[ -924us] +/-   43ms
-^+ bar.example.net               1   6   377    21  -2629us[-2619us] +/-   86ms
+^+ ntp2.example.net              1   6   377    21  -2629us[-2619us] +/-   86ms
 ----
 +
 The columns are as follows:
@@ -379,9 +379,9 @@ offset. This can be suffixed by _ns_ (indicating nanoseconds), _us_
 (indicating microseconds), _ms_ (indicating milliseconds), or _s_ (indicating
 seconds). The number to the left of the square brackets shows the original
 measurement, adjusted to allow for any slews applied to the local clock
-since. The number following the _+/-_ indicator shows the margin of error in
+since. Positive offsets indicate that the local clock is ahead of the source.
-the measurement. Positive offsets indicate that the local clock is ahead of
+The number following the _+/-_ indicator shows the margin of error in the
-the source.
+measurement (NTP root distance).
 
 [[sourcestats]]*sourcestats* [*-a*] [*-v*]::
 The *sourcestats* command displays information about the drift rate and offset
@@ -400,7 +400,7 @@ An example report is:
 ----
 Name/IP Address            NP  NR  Span  Frequency  Freq Skew  Offset  Std Dev
 ===============================================================================
-foo.example.net            11   5   46m     -0.001      0.045      1us    25us
+ntp1.example.net           11   5   46m     -0.001      0.045      1us    25us
 ----
 +
 The columns are as follows:
@@ -444,9 +444,9 @@ An example of the output is shown below.
 ----
 S Name/IP Address        Auth COpts EOpts Last Score     Interval  Leap
 =======================================================================
-D foo.example.net           Y ----- --TR-    4   1.0   -61ms   +62ms  N
+D ntp1.example.net          Y ----- --TR-    4   1.0   -61ms   +62ms  N
-* bar.example.net           N ----- -----    0   1.0 -6846us +7305us  N
+* ntp2.example.net          N ----- -----    0   1.0 -6846us +7305us  N
-+ baz.example.net           N ----- -----   10   1.0 -7381us +7355us  N
++ ntp3.example.net          N ----- -----   10   1.0 -7381us +7355us  N
 ----
 +
 The columns are as follows:
@@ -459,8 +459,8 @@ states are reported.
 The following states indicate the source is not considered selectable for
 synchronisation:
 * _N_ - has the *noselect* option.
-* _s_ - is not synchronised.
 * _M_ - does not have enough measurements.
+* _s_ - is not synchronised.
 * _d_ - has a root distance larger than the maximum distance (configured by the
         <<chrony.conf.adoc#maxdistance,*maxdistance*>> directive).
 * _~_ - has a jitter larger than the maximum jitter (configured by the
@@ -492,7 +492,7 @@ local clock:
 This column shows the name or IP address of the source if it is an NTP server,
 or the reference ID if it is a reference clock.
 *Auth*:::
-This column indicites whether an authentication mechanism is enabled for the
+This column indicates whether an authentication mechanism is enabled for the
 source. _Y_ means yes and _N_ means no.
 *COpts*:::
 This column displays the configured selection options of the source.
@@ -556,6 +556,13 @@ The *reselectdist* command sets the reselection distance. It is equivalent to
 the <<chrony.conf.adoc#reselectdist,*reselectdist*>> directive in the
 configuration file.
 
+[[offset]]*offset* _address|refid_ _offset_::
+The *offset* command modifies the offset correction of an NTP source specified
+by IP address (or the _ID#XXXXXXXXXX_ identifier used for unknown addresses),
+or a reference clock specified by reference ID as a string. It is equivalent to
+the *offset* option in the <<chrony.conf.adoc#server,*server*>> or
+<<chrony.conf.adoc#refclock,*refclock*>> directive respectively.
+
 === NTP sources
 
 [[activity]]*activity*::
@@ -592,9 +599,9 @@ shown below.
 ----
 Name/IP address             Mode KeyID Type KLen Last Atmp  NAK Cook CLen
 =========================================================================
-foo.example.net              NTS     1   15  256 135m    0    0    8  100
+ntp1.example.net             NTS     1   15  256 135m    0    0    8  100
-bar.example.net               SK    30   13  128    -    0    0    0    0
+ntp2.example.net              SK    30   13  128    -    0    0    0    0
-baz.example.net                -     0    0    0    -    0    0    0    0
+ntp3.example.net               -     0    0    0    -    0    0    0    0
 ----
 +
 The columns are as follows:
@@ -689,6 +696,10 @@ Total TX        : 24
 Total RX        : 24
 Total valid RX  : 24
 Total good RX   : 22
+Total kernel TX : 24
+Total kernel RX : 24
+Total HW TX     : 0
+Total HW RX     : 0
 ----
 +
 The fields are explained as follows:
@@ -746,6 +757,18 @@ The number of packets which passed the first two groups of NTP tests.
 *Total good RX*:::
 The number of packets which passed all three groups of NTP tests, i.e. the NTP
 measurement was accepted.
+*Total kernel TX*:::
+The number of packets sent to the source for which a timestamp was captured by
+the kernel.
+*Total kernel RX*:::
+The number of packets received from the source for which a timestamp was
+captured by the kernel.
+*Total HW TX*:::
+The number of packets sent to the source for which a timestamp was captured by
+the NIC.
+*Total HW RX*:::
+The number of packets received from the source for which a timestamp was
+captured by the NIC.
 
 [[add_peer]]*add peer* _name_ [_option_]...::
 The *add peer* command allows a new NTP peer to be added whilst
@@ -758,7 +781,7 @@ parameters and options is identical to that for the
 An example of using this command is shown below.
 +
 ----
-add peer foo.example.net minpoll 6 maxpoll 10 key 25
+add peer ntp1.example.net minpoll 6 maxpoll 10 key 25
 ----
 
 [[add_pool]]*add pool* _name_ [_option_]...::
@@ -772,7 +795,7 @@ directive in the configuration file.
 An example of using this command is shown below:
 +
 ----
-add pool foo.example.net maxsources 3 iburst
+add pool ntp1.example.net maxsources 3 iburst
 ----
 
 [[add_server]]*add server* _name_ [_option_]...::
@@ -786,7 +809,7 @@ directive in the configuration file.
 An example of using this command is shown below:
 +
 ----
-add server foo.example.net minpoll 6 maxpoll 10 key 25
+add server ntp1.example.net minpoll 6 maxpoll 10 key 25
 ----
 
 [[delete]]*delete* _address_::
@@ -862,7 +885,7 @@ IPv6 addresses have first 48 bits equal to _2001:db8:789a_.
 Example of the three-argument form of the command is:
 +
 ----
-burst 2/10 foo.example.net
+burst 2/10 ntp1.example.net
 ----
 
 [[maxdelay]]*maxdelay* _address_ _delay_::
@@ -928,7 +951,7 @@ uses an IP address or a hostname. These forms are illustrated below.
 offline
 offline 255.255.255.0/1.2.3.0
 offline 2001:db8:789a::/48
-offline foo.example.net
+offline ntp1.example.net
 ----
 +
 The second form means that the *offline* command is to be applied to any source
@@ -986,6 +1009,10 @@ command might replace the addresses even if they are still in the pool.
 The *reload sources* command causes *chronyd* to re-read all _*.sources_ files
 from the directories specified by the
 <<chrony.conf.adoc#sourcedir,*sourcedir*>> directive.
++
+Note that modified sources (e.g. specified with a new option) are not modified
+in memory. They are removed and added again, which causes them to lose old
+measurements and reset the selection state.
 
 [[sourcename]]*sourcename* _address_::
 The *sourcename* command prints the original hostname or address that was
@@ -1094,7 +1121,7 @@ particular host.
 Examples of use, showing a named host and a numeric IP address, are as follows:
 +
 ----
-accheck foo.example.net
+accheck ntp1.example.net
 accheck 1.2.3.4
 accheck 2001:db8::1
 ----
@@ -1121,7 +1148,7 @@ An example of the output is:
 Hostname                      NTP   Drop Int IntL Last     Cmd   Drop Int  Last
 ===============================================================================
 localhost                       2      0   2   -   133      15      0  -1     7
-foo.example.net                12      0   6   -    23       0      0   -     -
+ntp1.example.net               12      0   6   -    23       0      0   -     -
 ----
 +
 Each row shows the data for a single host. Only hosts that have passed the host
@@ -1321,7 +1348,7 @@ used to check whether monitoring access is permitted from a named host.
 Examples of use are as follows:
 +
 ----
-cmdaccheck foo.example.net
+cmdaccheck ntp1.example.net
 cmdaccheck 1.2.3.4
 cmdaccheck 2001:db8::1
 ----
@@ -1548,7 +1575,7 @@ The *help* command displays a summary of the commands and their arguments.
 == BUGS
 
 For instructions on how to report bugs, please visit
-https://chrony.tuxfamily.org/.
+https://chrony-project.org/.
 
 == AUTHORS
 

doc/chronyd.adoc

@@ -72,9 +72,9 @@ terminal.
 
 *-L* _level_::
 This option specifies the minimum severity level of messages to be written to
-the log file, syslog, or terminal. The following levels can be specified:
+the log file, syslog, or terminal. The following levels can be specified: -1
-0 (informational), 1 (warning), 2 (non-fatal error), and 3 (fatal error). The
+(debug, if compiled with enabled support for debugging), 0 (informational), 1
-default value is 0.
+(warning), 2 (non-fatal error), and 3 (fatal error). The default value is 0.
 
 *-p*::
 When run in this mode, *chronyd* will print the configuration and exit. It will
@@ -206,6 +206,17 @@ With this option *chronyd* will print version number to the terminal and exit.
 *-h*, *--help*::
 With this option *chronyd* will print a help message to the terminal and exit.
 
+== ENVIRONMENT VARIABLES
+
+*LISTEN_FDS*::
+On Linux systems, the systemd service manager may pass file descriptors for
+pre-initialised sockets to *chronyd*. The service manager allocates and binds
+the file descriptors, and passes a copy to each spawned instance of the
+service. This allows for zero-downtime service restarts as the sockets buffer
+client requests until the service is able to handle them. The service manager
+sets the LISTEN_FDS environment variable to the number of passed file
+descriptors.
+
 == FILES
 
 _@SYSCONFDIR@/chrony.conf_
@@ -217,7 +228,7 @@ _@SYSCONFDIR@/chrony.conf_
 == BUGS
 
 For instructions on how to report bugs, please visit
-https://chrony.tuxfamily.org/.
+https://chrony-project.org/.
 
 == AUTHORS
 

doc/contributing.adoc

@@ -0,0 +1,74 @@
+// This file is part of chrony
+//
+// Copyright (C) Miroslav Lichvar  2024
+//
+// 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.
+
+= Contributing
+
+== Patches
+
+The source code of `chrony` is maintained in a git repository at
+https://gitlab.com/chrony/chrony. Patches can be submitted to the `chrony-dev`
+mailing list, or as a merge request on gitlab. Before spending a lot of time
+implementing a new major feature, it is recommended to ask on the mailing list
+for comments about its design and whether such feature fits the goals of the
+project.
+
+Each commit should be a self-contained logical change, which does not break
+the build or tests. New functionality and fixed bugs should be covered by a new
+test or an extended existing test in the test suite. The test can be included
+in the same commit or added as a separate commit. The same rule applies to
+documentation. All command-line options, configuration directives, and
+`chronyc` commands should be documented.
+
+The most important tests can be executed by running `make check` or `make
+quickcheck`. The unit and system tests run on all supported systems. The system
+tests require root privileges. The simulation tests run only on Linux and
+require https://gitlab.com/chrony/clknetsim[clknetsim] to be compiled in the
+directory containing the tests, but they are executed with a merge request on
+gitlab.
+
+The commit message should explain any non-trivial changes, e.g. what problem is
+the commit solving and how. The commit subject (first line of the message)
+should be written in an imperative form, prefixed with the component name if it
+is not a more general change, starting in lower case, and no period at the end.
+See the git log for examples.
+
+Simpler code is better. Less code is better. Security is a top priority.
+
+Assertions should catch only bugs in the `chrony` code. Unexpected values in
+external input (e.g. anything received from network) must be handled correctly
+without crashing and memory corruption. Fuzzing support is available at
+https://gitlab.com/chrony/chrony-fuzz. The fuzzing coverage is checked by the
+project maintainer before each release.
+
+The code should mostly be self-documenting. Comments should explain the
+less obvious things.
+
+== Coding style
+
+The code uses two spaces for indentation. No tabs. The line length should
+normally not exceed 95 characters. Too much indentation indicates the code will
+not be very readable.
+
+Function names are in an imperative form. Names of static functions use
+lowercase characters and underscores. Public functions, structures, typedefs
+are in CamelCase with a prefix specific to the module (e.g. LCL - local, NCR
+- NTP core, NKS - NTS-KE server, SST - sourcestats).
+
+Function names are not followed by space, but keywords of the language (e.g.
+`if`, `for`, `while`, `sizeof`) are followed by space.
+
+Have a look at the existing code to get a better idea what is expected.

doc/faq.adoc

@@ -1,7 +1,8 @@
 // This file is part of chrony
 //
 // Copyright (C) Richard P. Curnow  1997-2003
-// Copyright (C) Miroslav Lichvar  2014-2016, 2020-2022
+// Copyright (C) Luke Valenta  2023
+// Copyright (C) Miroslav Lichvar  2014-2016, 2020-2024
 //
 // 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
@@ -40,9 +41,36 @@ on an isolated network with no hardware reference clocks in sight, `chrony`
 will probably work better for you.
 
 For a more detailed comparison of features and performance, see the
-https://chrony.tuxfamily.org/comparison.html[comparison page] on the `chrony`
+https://chrony-project.org/comparison.html[comparison page] on the `chrony`
 website.
 
+=== Should I prefer `chrony` over `timesyncd` if I do not need to run a server?
+
+Generally, yes.
+
+`systemd-timesyncd` is a very simple NTP client included in the `systemd`
+suite. It lacks almost all features of `chrony` and other advanced client
+implementations listed on the
+https://chrony-project.org/comparison.html[comparison page]. One of its main
+limitations is that it cannot poll multiple servers at the same time and detect
+servers having incorrect time (falsetickers in the NTP terminology). It should
+be used only with trusted reliable servers, ideally in local network.
+
+Using `timesyncd` with `pool.ntp.org` is problematic. The pool is very
+robust as a whole, but the individual servers run by volunteers cannot be
+relied on. Occasionally, servers drift away or make a step to distant past or
+future due to misconfiguration, problematic implementation, and other bugs
+(e.g. in firmware of a GPS receiver). The pool monitoring system detects such
+servers and quickly removes them from the pool DNS, but clients like
+`timesyncd` cannot recover from that. They follow the server as long as it
+claims to be synchronised. They need to be restarted in order to get a new
+address from the pool DNS.
+
+Note that the complexity of NTP and clock synchronisation is on the client
+side. The amount of code in `chrony` specific to NTP server is very small and
+it is disabled by default. If it was removed, it would not significantly reduce
+the amount of memory or storage needed.
+
 == Configuration issues
 
 === What is the minimum recommended configuration for an NTP client?
@@ -238,11 +266,11 @@ An example of a client configuration limiting the impact of the attacks could
 be
 
 ----
-server foo.example.net iburst nts maxdelay 0.1
+server ntp1.example.net iburst nts maxdelay 0.1
-server bar.example.net iburst nts maxdelay 0.2
+server ntp2.example.net iburst nts maxdelay 0.2
-server baz.example.net iburst nts maxdelay 0.05
+server ntp3.example.net iburst nts maxdelay 0.05
-server qux.example.net iburst nts maxdelay 0.1
+server ntp4.example.net iburst nts maxdelay 0.1
-server quux.example.net iburst nts maxdelay 0.1
+server ntp5.example.net iburst nts maxdelay 0.1
 minsources 3
 maxchange 100 0 0
 makestep 0.001 1
@@ -291,7 +319,7 @@ An example of the directive for an NTP server on the Internet that you are
 allowed to poll frequently could be
 
 ----
-server foo.example.net minpoll 4 maxpoll 6 polltarget 16
+server ntp.example.net minpoll 4 maxpoll 6 polltarget 16
 ----
 
 An example using shorter polling intervals with a server located in the same
@@ -354,7 +382,7 @@ outliers corrupting the minimum delay. For example:
 server ntp.local minpoll -7 maxpoll -7 filter 31 maxdelayquant 0.3 xleave
 ----
 
-As an experimental feature added in version 4.2, `chronyd` supports an NTPv4
+Since version 4.2, `chronyd` supports an NTPv4
 extension field containing an additional timestamp to enable frequency transfer
 and significantly improve stability of synchronisation. It can be enabled by
 the `extfield F323` option. For example:
@@ -363,6 +391,18 @@ the `extfield F323` option. For example:
 server ntp.local minpoll 0 maxpoll 0 xleave extfield F323
 ----
 
+Since version 4.5, `chronyd` can apply corrections from PTP one-step end-to-end
+transparent clocks (e.g. network switches) to significantly improve accuracy of
+synchronisation in local networks. It requires the PTP transport to be enabled
+by the `ptpport` directive, HW timestamping, and the `extfield F324` option.
+For example:
+
+----
+server ntp.local minpoll -4 maxpoll -4 xleave extfield F323 extfield F324 port 319
+ptpport 319
+hwtimestamp eth0 minpoll -4
+----
+
 === Does `chronyd` have an ntpdate mode?
 
 Yes. With the `-q` option `chronyd` will set the system clock once and exit.
@@ -470,6 +510,59 @@ pidfile /var/run/chronyd-server1.pid
 driftfile /var/lib/chrony/drift-server1
 ----
 
+=== How can `chronyd` be configured to minimise downtime during restarts?
+
+The `dumpdir` directive in _chrony.conf_ provides `chronyd` a location to save
+a measurement history of the sources it uses when the service exits. The `-r`
+option then enables `chronyd` to load state from the dump files, reducing the
+synchronisation time after a restart.
+
+Similarly, the `ntsdumpdir` directive provides a location for `chronyd` to save
+NTS cookies received from the server to avoid making a NTS-KE request when
+`chronyd` is started. When operating as an NTS server, `chronyd` also saves
+cookies keys to this directory to allow clients to continue to use the old keys
+after a server restart for a more seamless experience.
+
+On Linux systems,
+https://www.freedesktop.org/software/systemd/man/latest/sd_listen_fds.html[systemd
+socket activation] provides a mechanism to reuse server sockets across
+`chronyd` restarts, so that client requests will be buffered until the service
+is again able to handle the requests. This allows for zero-downtime service
+restarts, simplified dependency logic at boot, and on-demand service spawning
+(for instance, for separated server `chronyd` instances run with the `-x`
+flag).
+
+Socket activation is supported since `chrony` version 4.5.
+The service manager (systemd) creates sockets and
+passes file descriptors to them to the process via the `LISTEN_FDS` environment
+variable. Before opening new sockets, `chronyd` first checks for and attempts
+to reuse matching sockets passed from the service manager. For instance, if an
+IPv4 datagram socket bound on `bindaddress` and `port` is available, it will be
+used by the NTP server to accept incoming IPv4 requests.
+
+An example systemd socket unit is below, where `chronyd` is configured with
+`bindaddress 0.0.0.0`, `bindaddress ::`, `port 123`, and `ntsport 4460`.
+
+----
+[Unit]
+Description=chronyd server sockets
+
+[Socket]
+Service=chronyd.service
+# IPv4 NTP server
+ListenDatagram=0.0.0.0:123
+# IPv6 NTP server
+ListenDatagram=[::]:123
+# IPv4 NTS-KE server
+ListenStream=0.0.0.0:4460
+# IPv6 NTS-KE server
+ListenStream=[::]:4460
+BindIPv6Only=ipv6-only
+
+[Install]
+WantedBy=sockets.target
+----
+
 === Should be a leap smear enabled on NTP server?
 
 With the `smoothtime` and `leapsecmode` directives it is possible to enable a
@@ -484,7 +577,7 @@ identically configured leap-smearing servers. Note that some clients can get
 leap seconds from other sources (e.g. with the `leapsectz` directive in
 `chrony`) and they will not work correctly with a leap smearing server.
 
-=== How should `chronyd` be configuration with `gpsd`?
+=== How should `chronyd` be configured with `gpsd`?
 
 A GPS or other GNSS receiver can be used as a reference clock with `gpsd`. It
 can work as one or two separate time sources for each connected receiver. The
@@ -571,7 +664,28 @@ The `ethtool -T` command can be used to verify the timestamping support.
 As an experimental feature added in version 4.2, `chrony` can use PTP as a
 transport for NTP messages (NTP over PTP) to enable hardware timestamping on
 hardware which can timestamp PTP packets only. It can be enabled by the
-`ptpport` directive.
+`ptpport` directive. Since version 4.5, `chrony` can also apply corrections
+provided by PTP one-step end-to-end transparent clocks to reach the accuracy of
+ordinary PTP clocks. The application of PTP corrections can be enabled by the
+`extfield F324` option.
+
+=== How can I avoid using wrong PHC refclock?
+
+If your system has multiple PHC devices, normally named by `udev` as
+_/dev/ptp0_, _/dev/ptp1_, and so on, their order can change randomly across
+reboots depending on the order of initialisation of their drivers. If a PHC
+refclock is specified by this name, `chronyd` could be using a wrong refclock
+after reboot. To prevent that, you can configure `udev` to create a stable
+symlink for `chronyd` with a rule like this (e.g. written to
+_/etc/udev/rules.d/80-phc.rules_):
+
+----
+KERNEL=="ptp[0-9]*", DEVPATH=="/devices/pci0000:00/0000:00:01.2/0000:02:00.0/ptp/*", SYMLINK+="ptp-i350-1"
+----
+
+You can get the full _DEVPATH_ of an existing PHC device with the `udevadm
+info` command. You will need to execute the `udevadm trigger` command, or
+reboot the system, for these changes to take effect.
 
 === Why are client log records dropped before reaching `clientloglimit`?
 
@@ -624,9 +738,9 @@ this:
 ----
 MS Name/IP address         Stratum Poll Reach LastRx Last sample
 ===============================================================================
-^* foo.example.net               2   6   377    34   +484us[ -157us] +/-   30ms
+^* ntp1.example.net              2   6   377    34   +484us[ -157us] +/-   30ms
-^- bar.example.net               2   6   377    34    +33ms[  +32ms] +/-   47ms
+^- ntp2.example.net              2   6   377    34    +33ms[  +32ms] +/-   47ms
-^+ baz.example.net               3   6   377    35  -1397us[-2033us] +/-   60ms
+^+ ntp3.example.net              3   6   377    35  -1397us[-2033us] +/-   60ms
 ----
 
 === Are NTP servers specified with the `offline` option?
@@ -658,6 +772,17 @@ print all sources, even those that do not have a known address yet, with their
 names as they were specified in the configuration. This can be useful to verify
 that the names specified in the configuration are used as expected.
 
+When DNSSEC is enabled, it will not work until the time is synchronized, as it
+requires validating a signature timestamp and its expiration date, so if the
+system time is too far in the future or the past DNSSEC validation will fail and
+`chronyd` will be unable to resolve the address of the NTP server. In such cases,
+if hostnames are the only options and bare IP addresses cannot be used, DNSSEC
+can be disabled for `chronyd` using resolver-specific mechanisms, if available,
+although of course that means losing the protection afforded by DNSSEC.
+For example, when using systemd-resolved, the `SYSTEMD_NSS_RESOLVE_VALIDATE=0`
+environment variable can be set, for example in the `chronyd` systemd unit via
+`Environment=SYSTEMD_NSS_RESOLVE_VALIDATE=0`.
+
 === Is `chronyd` allowed to step the system clock?
 
 By default, `chronyd` adjusts the clock gradually by slowing it down or
@@ -696,9 +821,9 @@ successful:
 # chronyc -N authdata
 Name/IP address             Mode KeyID Type KLen Last Atmp  NAK Cook CLen
 =========================================================================
-foo.example.net              NTS     1   15  256  33m    0    0    8  100
+ntp1.example.net             NTS     1   15  256  33m    0    0    8  100
-bar.example.net              NTS     1   15  256  33m    0    0    8  100
+ntp2.example.net             NTS     1   15  256  33m    0    0    8  100
-baz.example.net              NTS     1   15  256  33m    0    0    8  100
+ntp3.example.net             NTS     1   15  256  33m    0    0    8  100
 ----
 
 The KeyID, Type, and KLen columns should have non-zero values. If they are
@@ -822,7 +947,7 @@ Name/IP Address            NP  NR  Span  Frequency  Freq Skew  Offset  Std Dev
 ==============================================================================
 PPS0                        0   0     0     +0.000   2000.000     +0ns  4000ms
 NMEA                       58  30   231    -96.494     38.406   +504ms  6080us
-foo.example.net             7   3   200     -2.991     16.141   -107us   492us
+ntp1.example.net            7   3   200     -2.991     16.141   -107us   492us
 ----
 
 the offset of the NMEA source would need to be increased by about 0.504
@@ -1041,6 +1166,53 @@ There are several different clocks used by `chronyd`:
   synchronised by `chronyd`. Its offset is tracked relative to the NTP clock in
   order to convert the hardware timestamps.
 
+=== How accurate is my system clock?
+
+`chronyd` does not know how accurate really is the clock it is synchronizing.
+Even if the measured offset of the clock is stable to nanoseconds, it could be
+off by milliseconds due to asymmetric network delay, e.g. caused by asymmetric
+routing or queuing delays in network switches. NTP provides root delay and root
+dispersion to enable clients to estimate the maximum error of their clock.
+
+Root delay measures the sum of round-trip times between all NTP servers on the
+path from the client to the primary time source (e.g. a GPS receiver). Half of
+the root delay is the maximum error due to asymmetric delays, assuming one
+direction (e.g. from the client to the server) has a zero delay and the other
+direction (from the server to the client) takes all of the measured delay. The
+root delay also covers timestamping errors if the server implementation and
+hardware meet the NTP requirement for transmit timestamps to never be late and
+receive timestamps to never be early.
+
+If you have additional information about the hardware and network between the
+client and primary time source, you could modify the root delay to get a better
+estimate of the maximum error. For example, from the physical distance of the
+server and signal propagation speed in the cables a minimum symmetric
+round-trip delay can be calculated and subtracted from the root delay measured
+by NTP.
+
+Root dispersion estimates errors due to instability of clocks and NTP
+measurements. `chronyd` adjusts the rate at which root dispersion grows between
+updates of the clock according to the stability of its NTP measurements. The
+minimum rate is set by the the `maxclockerror` directive. By default it is 1
+ppm (1 microsecond per second).
+
+The estimated maximum error of the NTP clock is the sum of the root dispersion
+and half of the root delay. This value is called root distance. The current
+values of root dispersion and delay are included in the `tracking` report.
+
+The estimated maximum error of the system clock, which is synchronized to the
+NTP clock, is the sum of the root distance and remaining correction of the
+system clock provided as `System time` in the `tracking` report. A maximum
+value of this estimate between updates of the clock is included in the
+`tracking` log.
+
+Note that the resolution of the root delay and root dispersion fields in NTP
+messages is about 15 microseconds and `chronyd` rounds the values up, i.e. the
+minimum root distance an NTP client can normally observe is about 22.5
+microseconds. An NTP extension field containing root delay and dispersion in a
+better resolution of about 4 nanoseconds can be enabled by the `extfield F323`
+option.
+
 == Operating systems
 
 === Does `chrony` support Windows?

examples/chrony.conf.example2

@@ -37,8 +37,8 @@ ntsdumpdir /var/lib/chrony
 # Insert/delete leap seconds by slewing instead of stepping.
 #leapsecmode slew
 
-# Get TAI-UTC offset and leap seconds from the system tz database.
+# Set the TAI-UTC offset of the system clock.
-#leapsectz right/UTC
+#leapseclist /usr/share/zoneinfo/leap-seconds.list
 
 # Specify directory for log files.
 logdir /var/log/chrony

examples/chrony.conf.example3

@@ -27,9 +27,9 @@
 # you can access at http://support.ntp.org/bin/view/Servers/WebHome or
 # you can use servers from the pool.ntp.org project.
 
-! server foo.example.net iburst
+! server ntp1.example.net iburst
-! server bar.example.net iburst
+! server ntp2.example.net iburst
-! server baz.example.net iburst
+! server ntp3.example.net iburst
 
 ! pool pool.ntp.org iburst
  
@@ -99,8 +99,8 @@ ntsdumpdir /var/lib/chrony
 # and edit the following lines to specify the locations of the certificate and
 # key.
 
-! ntsservercert /etc/.../foo.example.net.crt
+! ntsservercert /etc/.../nts-server.crt
-! ntsserverkey /etc/.../foo.example.net.key
+! ntsserverkey /etc/.../nts-server.key
 
 # chronyd can save the measurement history for the servers to files when
 # it exits.  This is useful in 2 situations:
@@ -126,11 +126,11 @@ ntsdumpdir /var/lib/chrony
 
 ! pidfile /var/run/chrony/chronyd.pid
 
-# If the system timezone database is kept up to date and includes the
+# The system timezone database usually comes with a list of leap seconds and
-# right/UTC timezone, chronyd can use it to determine the current
+# corresponding TAI-UTC offsets.  chronyd can use it to set the offset of the
-# TAI-UTC offset and when will the next leap second occur.
+# system TAI clock and have an additional source of leap seconds.
 
-! leapsectz right/UTC
+! leapseclist /usr/share/zoneinfo/leap-seconds.list
 
 #######################################################################
 ### INITIAL CLOCK CORRECTION
@@ -238,7 +238,7 @@ ntsdumpdir /var/lib/chrony
 # several people, you need to set up a mailing list or sendmail alias
 # for them and use the address of that.)
 
-! mailonchange wibble@foo.example.net 0.5
+! mailonchange wibble@example.net 0.5
 
 #######################################################################
 ### COMMAND ACCESS

getdate.y

@@ -943,6 +943,7 @@ get_date (const char *p, const time_t *now)
   tm.tm_hour += yyRelHour;
   tm.tm_min += yyRelMinutes;
   tm.tm_sec += yyRelSeconds;
+  tm.tm_wday = 0;
 
   /* Let mktime deduce tm_isdst if we have an absolute timestamp,
      or if the relative timestamp mentions days, months, or years.  */

leapdb.c

@@ -0,0 +1,272 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2009-2018, 2020, 2022
+ * Copyright (C) Patrick Oppenlander 2023, 2024
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ **********************************************************************
+
+  =======================================================================
+
+  This module provides leap second information. */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "conf.h"
+#include "leapdb.h"
+#include "logging.h"
+#include "util.h"
+
+/* ================================================== */
+
+/* Source of leap second data */
+enum {
+  SRC_NONE,
+  SRC_TIMEZONE,
+  SRC_LIST,
+} leap_src;
+
+/* Offset between leap-seconds.list timestamp epoch and Unix epoch.
+   leap-seconds.list epoch is 1 Jan 1900, 00:00:00 */
+#define LEAP_SEC_LIST_OFFSET 2208988800
+
+/* ================================================== */
+
+static NTP_Leap
+get_tz_leap(time_t when, int *tai_offset)
+{
+  struct tm stm, *tm;
+  time_t t;
+  char *tz_env, tz_orig[128];
+  NTP_Leap tz_leap = LEAP_Normal;
+
+  tm = gmtime(&when);
+  if (!tm)
+    return tz_leap;
+
+  stm = *tm;
+
+  /* Temporarily switch to the timezone containing leap seconds */
+  tz_env = getenv("TZ");
+  if (tz_env) {
+    if (strlen(tz_env) >= sizeof (tz_orig))
+      return tz_leap;
+    strcpy(tz_orig, tz_env);
+  }
+  setenv("TZ", CNF_GetLeapSecTimezone(), 1);
+  tzset();
+
+  /* Get the TAI-UTC offset, which started at the epoch at 10 seconds */
+  t = mktime(&stm);
+  if (t != -1)
+    *tai_offset = t - when + 10;
+
+  /* Set the time to 23:59:60 and see how it overflows in mktime() */
+  stm.tm_sec = 60;
+  stm.tm_min = 59;
+  stm.tm_hour = 23;
+
+  t = mktime(&stm);
+
+  if (tz_env)
+    setenv("TZ", tz_orig, 1);
+  else
+    unsetenv("TZ");
+  tzset();
+
+  if (t == -1)
+    return tz_leap;
+
+  if (stm.tm_sec == 60)
+    tz_leap = LEAP_InsertSecond;
+  else if (stm.tm_sec == 1)
+    tz_leap = LEAP_DeleteSecond;
+
+  return tz_leap;
+}
+
+/* ================================================== */
+
+static NTP_Leap
+get_list_leap(time_t when, int *tai_offset)
+{
+  FILE *f;
+  char line[1024];
+  NTP_Leap ret_leap = LEAP_Normal;
+  int ret_tai_offset = 0, prev_lsl_tai_offset = 10;
+  int64_t when1900, lsl_updated = 0, lsl_expiry = 0;
+  const char *leap_sec_list = CNF_GetLeapSecList();
+
+  if (!(f = UTI_OpenFile(NULL, leap_sec_list, NULL, 'r', 0))) {
+    LOG(LOGS_ERR, "Failed to open leap seconds list %s", leap_sec_list);
+    goto out;
+  }
+
+  /* Leap second happens at midnight */
+  when = (when / (24 * 3600) + 1) * (24 * 3600);
+
+  /* leap-seconds.list timestamps are relative to 1 Jan 1900, 00:00:00 */
+  when1900 = (int64_t)when + LEAP_SEC_LIST_OFFSET;
+
+  while (fgets(line, sizeof line, f) > 0) {
+    int64_t lsl_when;
+    int lsl_tai_offset;
+    char *p;
+
+    /* Ignore blank lines */
+    for (p = line; *p && isspace(*p); ++p)
+      ;
+    if (!*p)
+      continue;
+
+    if (*line == '#') {
+      /* Update time line starts with #$ */
+      if (line[1] == '$' && sscanf(line + 2, "%"SCNd64, &lsl_updated) != 1)
+        goto error;
+      /* Expiration time line starts with #@ */
+      if (line[1] == '@' && sscanf(line + 2, "%"SCNd64, &lsl_expiry) != 1)
+        goto error;
+      /* Comment or a special comment we don't care about */
+      continue;
+    }
+
+    /* Leap entry */
+    if (sscanf(line, "%"SCNd64" %d", &lsl_when, &lsl_tai_offset) != 2)
+      goto error;
+
+    if (when1900 == lsl_when) {
+      if (lsl_tai_offset > prev_lsl_tai_offset)
+        ret_leap = LEAP_InsertSecond;
+      else if (lsl_tai_offset < prev_lsl_tai_offset)
+        ret_leap = LEAP_DeleteSecond;
+      /* When is rounded to the end of the day, so offset hasn't changed yet! */
+      ret_tai_offset = prev_lsl_tai_offset;
+    } else if (when1900 > lsl_when) {
+      ret_tai_offset = lsl_tai_offset;
+    }
+
+    prev_lsl_tai_offset = lsl_tai_offset;
+  }
+
+  /* Make sure the file looks sensible */
+  if (!feof(f) || !lsl_updated || !lsl_expiry)
+    goto error;
+
+  if (when1900 >= lsl_expiry)
+    LOG(LOGS_WARN, "Leap second list %s needs update", leap_sec_list);
+
+  goto out;
+
+error:
+  if (f)
+    fclose(f);
+  LOG(LOGS_ERR, "Failed to parse leap seconds list %s", leap_sec_list);
+  return LEAP_Normal;
+
+out:
+  if (f)
+    fclose(f);
+  *tai_offset = ret_tai_offset;
+  return ret_leap;
+}
+
+/* ================================================== */
+
+static int
+check_leap_source(NTP_Leap (*src)(time_t when, int *tai_offset))
+{
+  int tai_offset = 0;
+
+  /* Check that the leap second source has good data for Jun 30 2012 and Dec 31 2012 */
+  if (src(1341014400, &tai_offset) == LEAP_InsertSecond && tai_offset == 34 &&
+      src(1356912000, &tai_offset) == LEAP_Normal && tai_offset == 35)
+    return 1;
+
+  return 0;
+}
+
+/* ================================================== */
+
+void
+LDB_Initialise(void)
+{
+  const char *leap_tzname, *leap_sec_list;
+
+  leap_tzname = CNF_GetLeapSecTimezone();
+  if (leap_tzname && !check_leap_source(get_tz_leap)) {
+    LOG(LOGS_WARN, "Timezone %s failed leap second check, ignoring", leap_tzname);
+    leap_tzname = NULL;
+  }
+
+  leap_sec_list = CNF_GetLeapSecList();
+  if (leap_sec_list && !check_leap_source(get_list_leap)) {
+    LOG(LOGS_WARN, "Leap second list %s failed check, ignoring", leap_sec_list);
+    leap_sec_list = NULL;
+  }
+
+  if (leap_sec_list) {
+    LOG(LOGS_INFO, "Using leap second list %s", leap_sec_list);
+    leap_src = SRC_LIST;
+  } else if (leap_tzname) {
+    LOG(LOGS_INFO, "Using %s timezone to obtain leap second data", leap_tzname);
+    leap_src = SRC_TIMEZONE;
+  }
+}
+
+/* ================================================== */
+
+NTP_Leap
+LDB_GetLeap(time_t when, int *tai_offset)
+{
+  static time_t last_ldb_leap_check;
+  static NTP_Leap ldb_leap;
+  static int ldb_tai_offset;
+
+  /* Do this check at most twice a day */
+  when = when / (12 * 3600) * (12 * 3600);
+  if (last_ldb_leap_check == when)
+    goto out;
+
+  last_ldb_leap_check = when;
+  ldb_leap = LEAP_Normal;
+  ldb_tai_offset = 0;
+
+  switch (leap_src) {
+  case SRC_NONE:
+    break;
+  case SRC_TIMEZONE:
+    ldb_leap = get_tz_leap(when, &ldb_tai_offset);
+    break;
+  case SRC_LIST:
+    ldb_leap = get_list_leap(when, &ldb_tai_offset);
+    break;
+  }
+
+out:
+  *tai_offset = ldb_tai_offset;
+  return ldb_leap;
+}
+
+/* ================================================== */
+
+void
+LDB_Finalise(void)
+{
+  /* Nothing to do */
+}

leapdb.h

@@ -0,0 +1,37 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Patrick Oppenlander 2024
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ **********************************************************************
+
+  =======================================================================
+
+  This module provides leap second information.
+
+  */
+
+#ifndef GOT_LEAPDB_H
+#define GOT_LEAPDB_H
+
+#include "ntp.h"
+
+extern void LDB_Initialise(void);
+extern NTP_Leap LDB_GetLeap(time_t when, int *tai_offset);
+extern void LDB_Finalise(void);
+
+#endif /* GOT_LEAPDB_H */

logging.c

@@ -145,6 +145,7 @@ void LOG_Message(LOG_Severity severity,
   struct tm *tm;
 
   assert(initialised);
+  severity = CLAMP(LOGS_DEBUG, severity, LOGS_FATAL);
 
   if (!system_log && file_log && severity >= log_min_severity) {
     /* Don't clutter up syslog with timestamps and internal debugging info */
@@ -155,8 +156,13 @@ void LOG_Message(LOG_Severity severity,
       fprintf(file_log, "%s ", buf);
     }
 #if DEBUG > 0
-    if (log_min_severity <= LOGS_DEBUG)
+    if (log_min_severity <= LOGS_DEBUG) {
-      fprintf(file_log, "%s%s:%d:(%s) ", debug_prefix, filename, line_number, function_name);
+      /* Log severity to character mapping (debug, info, warn, err, fatal) */
+      const char severity_chars[LOGS_FATAL - LOGS_DEBUG + 1] = {'D', 'I', 'W', 'E', 'F'};
+
+      fprintf(file_log, "%c:%s%s:%d:(%s) ", severity_chars[severity - LOGS_DEBUG],
+              debug_prefix, filename, line_number, function_name);
+    }
 #endif
   }
 
@@ -179,7 +185,7 @@ void LOG_Message(LOG_Severity severity,
       /* Send the message also to the foreground process if it is
          still running, or stderr if it is still open */
       if (parent_fd > 0) {
-        if (write(parent_fd, buf, strlen(buf) + 1) < 0)
+        if (!LOG_NotifyParent(buf))
           ; /* Not much we can do here */
       } else if (system_log && parent_fd == 0) {
         system_log = 0;
@@ -285,6 +291,17 @@ LOG_SetParentFd(int fd)
 
 /* ================================================== */
 
+int
+LOG_NotifyParent(const char *message)
+{
+  if (parent_fd <= 0)
+    return 1;
+
+  return write(parent_fd, message, strlen(message) + 1) > 0;
+}
+
+/* ================================================== */
+
 void
 LOG_CloseParentFd()
 {

logging.h

@@ -126,7 +126,10 @@ extern void LOG_OpenSystemLog(void);
 /* Stop using stderr and send fatal message to the foreground process */
 extern void LOG_SetParentFd(int fd);
 
-/* Close the pipe to the foreground process so it can exit */
+/* Send a message to the foreground process */
+extern int LOG_NotifyParent(const char *message);
+
+/* Close the pipe to the foreground process */
 extern void LOG_CloseParentFd(void);
 
 /* File logging functions */

main.c

@@ -32,6 +32,7 @@
 
 #include "main.h"
 #include "sched.h"
+#include "leapdb.h"
 #include "local.h"
 #include "sys.h"
 #include "ntp_io.h"
@@ -134,6 +135,7 @@ MAI_CleanupAndExit(void)
   RCL_Finalise();
   SRC_Finalise();
   REF_Finalise();
+  LDB_Finalise();
   RTC_Finalise();
   SYS_Finalise();
 
@@ -213,7 +215,10 @@ post_init_ntp_hook(void *anything)
     REF_SetMode(ref_mode);
   }
 
-  /* Close the pipe to the foreground process so it can exit */
+  /* Send an empty message to the foreground process so it can exit.
+     If that fails, indicating the process was killed, exit too. */
+  if (!LOG_NotifyParent(""))
+    SCH_QuitProgram();
   LOG_CloseParentFd();
 
   CNF_AddSources();
@@ -336,8 +341,8 @@ go_daemon(void)
 
     close(pipefd[1]);
     r = read(pipefd[0], message, sizeof (message));
-    if (r) {
+    if (r != 1 || message[0] != '\0') {
-      if (r > 0) {
+      if (r > 1) {
         /* Print the error message from the child */
         message[sizeof (message) - 1] = '\0';
         fprintf(stderr, "%s\n", message);
@@ -368,9 +373,9 @@ go_daemon(void)
       }
 
       /* Don't keep stdin/out/err from before. But don't close
-         the parent pipe yet. */
+         the parent pipe yet, or reusable file descriptors. */
       for (fd=0; fd<1024; fd++) {
-        if (fd != pipefd[1])
+        if (fd != pipefd[1] && !SCK_IsReusable(fd))
           close(fd);
       }
 
@@ -560,6 +565,9 @@ int main
   if (user_check && getuid() != 0)
     LOG_FATAL("Not superuser");
 
+  /* Initialise reusable file descriptors before fork */
+  SCK_PreInitialise();
+
   /* Turn into a daemon */
   if (!nofork) {
     go_daemon();
@@ -652,6 +660,7 @@ int main
   if (!geteuid())
     LOG(LOGS_WARN, "Running with root privileges");
 
+  LDB_Initialise();
   REF_Initialise();
   SST_Initialise();
   NSR_Initialise();

ntp.h

@@ -115,9 +115,11 @@ typedef struct {
 
 /* Non-authentication extension fields and corresponding internal flags */
 
-#define NTP_EF_EXP1                     0xF323
+#define NTP_EF_EXP_MONO_ROOT            0xF323
+#define NTP_EF_EXP_NET_CORRECTION       0xF324
 
-#define NTP_EF_FLAG_EXP1                0x1
+#define NTP_EF_FLAG_EXP_MONO_ROOT       0x1
+#define NTP_EF_FLAG_EXP_NET_CORRECTION  0x2
 
 /* Pre-NTPv5 experimental extension field */
 typedef struct {
@@ -126,9 +128,18 @@ typedef struct {
   NTP_int32 root_dispersion;
   NTP_int64 mono_receive_ts;
   uint32_t mono_epoch;
-} NTP_ExtFieldExp1;
+} NTP_EFExpMonoRoot;
 
-#define NTP_EF_EXP1_MAGIC 0xF5BEDD9AU
+#define NTP_EF_EXP_MONO_ROOT_MAGIC      0xF5BEDD9AU
+
+/* Experimental extension field to provide PTP corrections */
+typedef struct {
+  uint32_t magic;
+  NTP_int64 correction;
+  uint32_t reserved[3];
+} NTP_EFExpNetCorrection;
+
+#define NTP_EF_EXP_NET_CORRECTION_MAGIC 0x07AC2CEBU
 
 /* Authentication extension fields */
 

ntp_core.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2009-2022
+ * Copyright (C) Miroslav Lichvar  2009-2024
  * 
  * 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
@@ -215,16 +215,13 @@ struct NCR_Instance_Record {
   SPF_Instance filter;
   int filter_count;
 
-  /* Flag indicating HW transmit timestamps are expected */
-  int had_hw_tx_timestamp;
-
   /* Response waiting for a HW transmit timestamp of the request */
   struct SavedResponse *saved_response;
 
   int burst_good_samples_to_go;
   int burst_total_samples_to_go;
 
-  /* Report from last valid response */
+  /* Report from last valid response and packet/timestamp statistics */
   RPT_NTPReport report;
 };
 
@@ -317,6 +314,9 @@ static ARR_Instance broadcasts;
 /* Maximum acceptable change in server mono<->real offset */
 #define MAX_MONO_DOFFSET 16.0
 
+/* Maximum assumed frequency error in network corrections */
+#define MAX_NET_CORRECTION_FREQ 100.0e-6
+
 /* Invalid socket, different from the one in ntp_io.c */
 #define INVALID_SOCK_FD -2
 
@@ -376,6 +376,9 @@ do_size_checks(void)
   assert(offsetof(NTP_Packet, originate_ts)    == 24);
   assert(offsetof(NTP_Packet, receive_ts)      == 32);
   assert(offsetof(NTP_Packet, transmit_ts)     == 40);
+
+  assert(sizeof (NTP_EFExpMonoRoot) == 24);
+  assert(sizeof (NTP_EFExpNetCorrection) == 24);
 }
 
 /* ================================================== */
@@ -421,6 +424,8 @@ zero_local_timestamp(NTP_Local_Timestamp *ts)
   UTI_ZeroTimespec(&ts->ts);
   ts->err = 0.0;
   ts->source = NTP_TS_DAEMON;
+  ts->rx_duration = 0.0;
+  ts->net_correction = 0.0;
 }
 
 /* ================================================== */
@@ -794,8 +799,6 @@ NCR_ResetInstance(NCR_Instance instance)
   if (instance->filter)
     SPF_DropSamples(instance->filter);
   instance->filter_count = 0;
-
-  instance->had_hw_tx_timestamp = 0;
 }
 
 /* ================================================== */
@@ -1050,34 +1053,64 @@ receive_timeout(void *arg)
 /* ================================================== */
 
 static int
-add_ext_exp1(NTP_Packet *message, NTP_PacketInfo *info, struct timespec *rx,
+add_ef_mono_root(NTP_Packet *message, NTP_PacketInfo *info, struct timespec *rx,
-             double root_delay, double root_dispersion)
+                 double root_delay, double root_dispersion)
 {
   struct timespec mono_rx;
-  NTP_ExtFieldExp1 exp1;
+  NTP_EFExpMonoRoot ef;
   NTP_int64 ts_fuzz;
 
-  memset(&exp1, 0, sizeof (exp1));
+  memset(&ef, 0, sizeof (ef));
-  exp1.magic = htonl(NTP_EF_EXP1_MAGIC);
+  ef.magic = htonl(NTP_EF_EXP_MONO_ROOT_MAGIC);
 
   if (info->mode != MODE_CLIENT) {
-    exp1.root_delay = UTI_DoubleToNtp32f28(root_delay);
+    ef.root_delay = UTI_DoubleToNtp32f28(root_delay);
-    exp1.root_dispersion = UTI_DoubleToNtp32f28(root_dispersion);
+    ef.root_dispersion = UTI_DoubleToNtp32f28(root_dispersion);
     if (rx)
       UTI_AddDoubleToTimespec(rx, server_mono_offset, &mono_rx);
     else
       UTI_ZeroTimespec(&mono_rx);
     UTI_GetNtp64Fuzz(&ts_fuzz, message->precision);
-    UTI_TimespecToNtp64(&mono_rx, &exp1.mono_receive_ts, &ts_fuzz);
+    UTI_TimespecToNtp64(&mono_rx, &ef.mono_receive_ts, &ts_fuzz);
-    exp1.mono_epoch = htonl(server_mono_epoch);
+    ef.mono_epoch = htonl(server_mono_epoch);
   }
 
-  if (!NEF_AddField(message, info, NTP_EF_EXP1, &exp1, sizeof (exp1))) {
+  if (!NEF_AddField(message, info, NTP_EF_EXP_MONO_ROOT, &ef, sizeof (ef))) {
     DEBUG_LOG("Could not add EF");
     return 0;
   }
 
-  info->ext_field_flags |= NTP_EF_FLAG_EXP1;
+  info->ext_field_flags |= NTP_EF_FLAG_EXP_MONO_ROOT;
+
+  return 1;
+}
+
+/* ================================================== */
+
+static int
+add_ef_net_correction(NTP_Packet *message, NTP_PacketInfo *info,
+                      NTP_Local_Timestamp *local_rx)
+{
+  NTP_EFExpNetCorrection ef;
+
+  if (CNF_GetPtpPort() == 0) {
+    DEBUG_LOG("ptpport disabled");
+    return 1;
+  }
+
+  memset(&ef, 0, sizeof (ef));
+  ef.magic = htonl(NTP_EF_EXP_NET_CORRECTION_MAGIC);
+
+  if (info->mode != MODE_CLIENT && local_rx->net_correction > local_rx->rx_duration) {
+    UTI_DoubleToNtp64(local_rx->net_correction, &ef.correction);
+  }
+
+  if (!NEF_AddField(message, info, NTP_EF_EXP_NET_CORRECTION, &ef, sizeof (ef))) {
+    DEBUG_LOG("Could not add EF");
+    return 0;
+  }
+
+  info->ext_field_flags |= NTP_EF_FLAG_EXP_NET_CORRECTION;
 
   return 1;
 }
@@ -1229,9 +1262,13 @@ transmit_packet(NTP_Mode my_mode, /* The mode this machine wants to be */
     return 0;
 
   if (ext_field_flags) {
-    if (ext_field_flags & NTP_EF_FLAG_EXP1) {
+    if (ext_field_flags & NTP_EF_FLAG_EXP_MONO_ROOT) {
-      if (!add_ext_exp1(&message, &info, smooth_time ? NULL : &local_receive,
+      if (!add_ef_mono_root(&message, &info, smooth_time ? NULL : &local_receive,
-                        our_root_delay, our_root_dispersion))
+                            our_root_delay, our_root_dispersion))
+        return 0;
+    }
+    if (ext_field_flags & NTP_EF_FLAG_EXP_NET_CORRECTION) {
+      if (!add_ef_net_correction(&message, &info, local_rx))
         return 0;
     }
   }
@@ -1302,6 +1339,8 @@ transmit_packet(NTP_Mode my_mode, /* The mode this machine wants to be */
     local_tx->ts = local_transmit;
     local_tx->err = local_transmit_err;
     local_tx->source = NTP_TS_DAEMON;
+    local_tx->rx_duration = 0.0;
+    local_tx->net_correction = 0.0;
   }
 
   if (local_ntp_rx)
@@ -1495,6 +1534,14 @@ is_zero_data(unsigned char *data, int length)
 
 /* ================================================== */
 
+static int
+is_exp_ef(void *body, int body_length, int expected_body_length, uint32_t magic)
+{
+  return body_length == expected_body_length && *(uint32_t *)body == htonl(magic);
+}
+
+/* ================================================== */
+
 static int
 parse_packet(NTP_Packet *packet, int length, NTP_PacketInfo *info)
 {
@@ -1581,10 +1628,15 @@ parse_packet(NTP_Packet *packet, int length, NTP_PacketInfo *info)
       case NTP_EF_NTS_AUTH_AND_EEF:
         info->auth.mode = NTP_AUTH_NTS;
         break;
-      case NTP_EF_EXP1:
+      case NTP_EF_EXP_MONO_ROOT:
-        if (ef_body_length == sizeof (NTP_ExtFieldExp1) &&
+        if (is_exp_ef(ef_body, ef_body_length, sizeof (NTP_EFExpMonoRoot),
-            ntohl(((NTP_ExtFieldExp1 *)ef_body)->magic) == NTP_EF_EXP1_MAGIC)
+                      NTP_EF_EXP_MONO_ROOT_MAGIC))
-          info->ext_field_flags |= NTP_EF_FLAG_EXP1;
+          info->ext_field_flags |= NTP_EF_FLAG_EXP_MONO_ROOT;
+        break;
+      case NTP_EF_EXP_NET_CORRECTION:
+        if (is_exp_ef(ef_body, ef_body_length, sizeof (NTP_EFExpNetCorrection),
+                      NTP_EF_EXP_NET_CORRECTION_MAGIC))
+          info->ext_field_flags |= NTP_EF_FLAG_EXP_NET_CORRECTION;
         break;
       default:
         DEBUG_LOG("Unknown extension field type=%x", (unsigned int)ef_type);
@@ -1612,6 +1664,53 @@ parse_packet(NTP_Packet *packet, int length, NTP_PacketInfo *info)
 
 /* ================================================== */
 
+static void
+apply_net_correction(NTP_Sample *sample, NTP_Local_Timestamp *rx, NTP_Local_Timestamp *tx,
+                     double precision)
+{
+  double rx_correction, tx_correction, low_delay_correction;
+
+  /* Require some correction from transparent clocks to be present
+     in both directions (not just the local RX timestamp correction) */
+  if (rx->net_correction <= rx->rx_duration || tx->net_correction <= 0.0)
+    return;
+
+  /* With perfect corrections from PTP transparent clocks and short cables
+     the peer delay would be close to zero, or even negative if the server or
+     transparent clocks were running faster than client, which would invert the
+     sample weighting.  Adjust the correction to get a delay corresponding to
+     a direct connection to the server.  For simplicity, assume the TX and RX
+     link speeds are equal.  If not, the reported delay will be wrong, but it
+     will not cause an error in the offset. */
+  rx_correction = rx->net_correction - rx->rx_duration;
+  tx_correction = tx->net_correction - rx->rx_duration;
+
+  /* Use a slightly smaller value in the correction of delay to not overcorrect
+     if the transparent clocks run up to 100 ppm fast and keep a part of the
+     uncorrected delay for the sample weighting */
+  low_delay_correction = (rx_correction + tx_correction) *
+                         (1.0 - MAX_NET_CORRECTION_FREQ);
+
+  /* Make sure the correction is sane.  The values are not authenticated! */
+  if (low_delay_correction < 0.0 || low_delay_correction > sample->peer_delay) {
+    DEBUG_LOG("Invalid correction %.9f peer_delay=%.9f",
+              low_delay_correction, sample->peer_delay);
+    return;
+  }
+
+  /* Correct the offset and peer delay, but not the root delay to not
+     change the estimated maximum error */
+  sample->offset += (rx_correction - tx_correction) / 2.0;
+  sample->peer_delay -= low_delay_correction;
+  if (sample->peer_delay < precision)
+    sample->peer_delay = precision;
+
+  DEBUG_LOG("Applied correction rx=%.9f tx=%.9f dur=%.9f",
+            rx->net_correction, tx->net_correction, rx->rx_duration);
+}
+
+/* ================================================== */
+
 static int
 check_delay_ratio(NCR_Instance inst, SST_Stats stats,
                 struct timespec *sample_time, double delay)
@@ -1873,18 +1972,20 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
   /* Extension fields */
   int parsed, ef_length, ef_type, ef_body_length;
   void *ef_body;
-  NTP_ExtFieldExp1 *ef_exp1;
+  NTP_EFExpMonoRoot *ef_mono_root;
+  NTP_EFExpNetCorrection *ef_net_correction;
 
   NTP_Local_Timestamp local_receive, local_transmit;
   double remote_interval, local_interval, response_time;
-  double delay_time, precision, mono_doffset;
+  double delay_time, precision, mono_doffset, net_correction;
   int updated_timestamps;
 
   /* ==================== */
 
   stats = SRC_GetSourcestats(inst->source);
 
-  ef_exp1 = NULL;
+  ef_mono_root = NULL;
+  ef_net_correction = NULL;
 
   /* Find requested non-authentication extension fields */
   if (inst->ext_field_flags & info->ext_field_flags) {
@@ -1894,11 +1995,17 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
         break;
 
       switch (ef_type) {
-        case NTP_EF_EXP1:
+        case NTP_EF_EXP_MONO_ROOT:
-          if (inst->ext_field_flags & NTP_EF_FLAG_EXP1 &&
+          if (inst->ext_field_flags & NTP_EF_FLAG_EXP_MONO_ROOT &&
-              ef_body_length == sizeof (*ef_exp1) &&
+              is_exp_ef(ef_body, ef_body_length, sizeof (*ef_mono_root),
-              ntohl(((NTP_ExtFieldExp1 *)ef_body)->magic) == NTP_EF_EXP1_MAGIC)
+                        NTP_EF_EXP_MONO_ROOT_MAGIC))
-            ef_exp1 = ef_body;
+            ef_mono_root = ef_body;
+          break;
+        case NTP_EF_EXP_NET_CORRECTION:
+          if (inst->ext_field_flags & NTP_EF_FLAG_EXP_NET_CORRECTION &&
+              is_exp_ef(ef_body, ef_body_length, sizeof (*ef_net_correction),
+                        NTP_EF_EXP_NET_CORRECTION_MAGIC))
+            ef_net_correction = ef_body;
           break;
       }
     }
@@ -1907,9 +2014,9 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
   pkt_leap = NTP_LVM_TO_LEAP(message->lvm);
   pkt_version = NTP_LVM_TO_VERSION(message->lvm);
   pkt_refid = ntohl(message->reference_id);
-  if (ef_exp1) {
+  if (ef_mono_root) {
-    pkt_root_delay = UTI_Ntp32f28ToDouble(ef_exp1->root_delay);
+    pkt_root_delay = UTI_Ntp32f28ToDouble(ef_mono_root->root_delay);
-    pkt_root_dispersion = UTI_Ntp32f28ToDouble(ef_exp1->root_dispersion);
+    pkt_root_dispersion = UTI_Ntp32f28ToDouble(ef_mono_root->root_dispersion);
   } else {
     pkt_root_delay = UTI_Ntp32ToDouble(message->root_delay);
     pkt_root_dispersion = UTI_Ntp32ToDouble(message->root_dispersion);
@@ -1966,7 +2073,7 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
      response to the request, when at least one good response has already been
      accepted to avoid incorrectly confirming a tentative source. */
   if (valid_packet && synced_packet && !saved && !inst->valid_rx &&
-      inst->had_hw_tx_timestamp && inst->local_tx.source != NTP_TS_HARDWARE &&
+      NIO_IsHwTsEnabled() && inst->local_tx.source != NTP_TS_HARDWARE &&
       inst->report.total_good_count > 0) {
     if (save_response(inst, local_addr, rx_ts, message, info))
       return 1;
@@ -1994,11 +2101,11 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
        the new sample.  In the interleaved mode, cancel the correction out in
        remote timestamps of the previous request and response, which were
        captured before the source accumulated the new time corrections. */
-    if (ef_exp1 && inst->remote_mono_epoch == ntohl(ef_exp1->mono_epoch) &&
+    if (ef_mono_root && inst->remote_mono_epoch == ntohl(ef_mono_root->mono_epoch) &&
-        !UTI_IsZeroNtp64(&ef_exp1->mono_receive_ts) &&
+        !UTI_IsZeroNtp64(&ef_mono_root->mono_receive_ts) &&
         !UTI_IsZeroNtp64(&inst->remote_ntp_monorx)) {
       mono_doffset =
-          UTI_DiffNtp64ToDouble(&ef_exp1->mono_receive_ts, &inst->remote_ntp_monorx) -
+          UTI_DiffNtp64ToDouble(&ef_mono_root->mono_receive_ts, &inst->remote_ntp_monorx) -
           UTI_DiffNtp64ToDouble(&message->receive_ts, &inst->remote_ntp_rx);
       if (fabs(mono_doffset) > MAX_MONO_DOFFSET)
         mono_doffset = 0.0;
@@ -2006,6 +2113,12 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
       mono_doffset = 0.0;
     }
 
+    if (ef_net_correction) {
+      net_correction = UTI_Ntp64ToDouble(&ef_net_correction->correction);
+    } else {
+      net_correction = 0.0;
+    }
+
     /* Select remote and local timestamps for the new sample */
     if (interleaved_packet) {
       /* Prefer previous local TX and remote RX timestamps if it will make
@@ -2025,6 +2138,7 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
         UTI_Ntp64ToTimespec(&message->receive_ts, &remote_receive);
         UTI_Ntp64ToTimespec(&inst->remote_ntp_rx, &remote_request_receive);
         local_transmit = inst->local_tx;
+        local_transmit.net_correction = net_correction;
         root_delay = MAX(pkt_root_delay, inst->remote_root_delay);
         root_dispersion = MAX(pkt_root_dispersion, inst->remote_root_dispersion);
       }
@@ -2039,6 +2153,7 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
       remote_request_receive = remote_receive;
       local_receive = *rx_ts;
       local_transmit = inst->local_tx;
+      local_transmit.net_correction = net_correction;
       root_delay = pkt_root_delay;
       root_dispersion = pkt_root_dispersion;
     }
@@ -2083,6 +2198,9 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
     sample.root_delay = root_delay + sample.peer_delay;
     sample.root_dispersion = root_dispersion + sample.peer_dispersion;
 
+    /* Apply corrections from PTP transparent clocks if available and sane */
+    apply_net_correction(&sample, &local_receive, &local_transmit, precision);
+    
     /* If the source is an active peer, this is the minimum assumed interval
        between previous two transmissions (if not constrained by minpoll) */
     prev_remote_poll_interval = UTI_Log2ToDouble(MIN(inst->remote_poll,
@@ -2090,8 +2208,11 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
 
     /* Additional tests required to pass before accumulating the sample */
 
-    /* Test A requires that the minimum estimate of the peer delay is not
+    /* Test A combines multiple tests to avoid changing the measurements log
-       larger than the configured maximum, in both client modes that the server
+       format and ntpdata report.  It requires that the minimum estimate of the
+       peer delay is not larger than the configured maximum, it is not a
+       response in the 'warm up' exchange, the configured offset correction is
+       within the supported NTP interval, both client modes that the server
        processing time is sane, in interleaved client/server mode that the
        previous response was not in basic mode (which prevents using timestamps
        that minimise delay error), and in interleaved symmetric mode that the
@@ -2099,6 +2220,8 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
        a missed response */
     testA = sample.peer_delay - sample.peer_dispersion <= inst->max_delay &&
             precision <= inst->max_delay &&
+            inst->presend_done <= 0 &&
+            UTI_IsTimeOffsetSane(&sample.time, sample.offset) &&
             !(inst->mode == MODE_CLIENT && response_time > MAX_SERVER_INTERVAL) &&
             !(inst->mode == MODE_CLIENT && interleaved_packet &&
               UTI_IsZeroTimespec(&inst->prev_local_tx.ts) &&
@@ -2137,6 +2260,7 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
     sample.root_delay = sample.root_dispersion = 0.0;
     sample.time = rx_ts->ts;
     mono_doffset = 0.0;
+    net_correction = 0.0;
     local_receive = *rx_ts;
     local_transmit = inst->local_tx;
     testA = testB = testC = testD = 0;
@@ -2170,9 +2294,9 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
     /* If available, update the monotonic timestamp and accumulate the offset.
        This needs to be done here to not lose changes in remote_ntp_rx in
        symmetric mode when there are multiple responses per request. */
-    if (ef_exp1 && !UTI_IsZeroNtp64(&ef_exp1->mono_receive_ts)) {
+    if (ef_mono_root && !UTI_IsZeroNtp64(&ef_mono_root->mono_receive_ts)) {
-      inst->remote_mono_epoch = ntohl(ef_exp1->mono_epoch);
+      inst->remote_mono_epoch = ntohl(ef_mono_root->mono_epoch);
-      inst->remote_ntp_monorx = ef_exp1->mono_receive_ts;
+      inst->remote_ntp_monorx = ef_mono_root->mono_receive_ts;
       inst->mono_doffset += mono_doffset;
     } else {
       inst->remote_mono_epoch = 0;
@@ -2180,8 +2304,11 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
       inst->mono_doffset = 0.0;
     }
 
-    /* Don't use the same set of timestamps for the next sample */
+    inst->local_tx.net_correction = net_correction;
-    if (interleaved_packet)
+
+    /* Avoid reusing timestamps of an accumulated sample when switching
+       from basic mode to interleaved mode */
+    if (interleaved_packet || !good_packet)
       inst->prev_local_tx = inst->local_tx;
     else
       zero_local_timestamp(&inst->prev_local_tx);
@@ -2200,15 +2327,11 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
   /* Accept at most one response per request.  The NTP specification recommends
      resetting local_ntp_tx to make the following packets fail test2 or test3,
      but that would not allow the code above to make multiple updates of the
-     timestamps in symmetric mode.  Also, ignore presend responses. */
+     timestamps in symmetric mode. */
   if (inst->valid_rx) {
     test2 = test3 = 0;
     valid_packet = synced_packet = good_packet = 0;
   } else if (valid_packet) {
-    if (inst->presend_done) {
-      testA = 0;
-      good_packet = 0;
-    }
     inst->valid_rx = 1;
   }
 
@@ -2251,13 +2374,17 @@ process_response(NCR_Instance inst, int saved, NTP_Local_Address *local_addr,
 
     SRC_UpdateReachability(inst->source, synced_packet);
 
-    if (synced_packet) {
+    if (inst->copy) {
-      if (inst->copy && inst->remote_stratum > 0) {
+      /* Assume the reference ID and stratum of the server */
-        /* Assume the reference ID and stratum of the server */
+      if (synced_packet && inst->remote_stratum > 0) {
         inst->remote_stratum--;
         SRC_SetRefid(inst->source, ntohl(message->reference_id), &inst->remote_addr.ip_addr);
+      } else {
+        SRC_ResetInstance(inst->source);
       }
+    }
 
+    if (synced_packet) {
       SRC_UpdateStatus(inst->source, MAX(inst->remote_stratum, inst->min_stratum), pkt_leap);
 
       if (inst->delay_quant)
@@ -2409,6 +2536,10 @@ NCR_ProcessRxKnown(NCR_Instance inst, NTP_Local_Address *local_addr,
   NTP_PacketInfo info;
 
   inst->report.total_rx_count++;
+  if (rx_ts->source == NTP_TS_KERNEL)
+    inst->report.total_kernel_rx_ts++;
+  else if (rx_ts->source == NTP_TS_HARDWARE)
+    inst->report.total_hw_rx_ts++;
 
   if (!parse_packet(message, length, &info))
     return 0;
@@ -2531,6 +2662,7 @@ NCR_ProcessRxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_a
   NTP_Local_Timestamp local_tx, *tx_ts;
   NTP_int64 ntp_rx, *local_ntp_rx;
   int log_index, interleaved, poll, version;
+  CLG_Limit limit;
   uint32_t kod;
 
   /* Ignore the packet if it wasn't received by server socket */
@@ -2576,7 +2708,8 @@ NCR_ProcessRxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_a
   log_index = CLG_LogServiceAccess(CLG_NTP, &remote_addr->ip_addr, &rx_ts->ts);
 
   /* Don't reply to all requests if the rate is excessive */
-  if (log_index >= 0 && CLG_LimitServiceRate(CLG_NTP, log_index)) {
+  limit = log_index >= 0 ? CLG_LimitServiceRate(CLG_NTP, log_index) : CLG_PASS;
+  if (limit == CLG_DROP) {
       DEBUG_LOG("NTP packet discarded to limit response rate");
       return;
   }
@@ -2590,6 +2723,13 @@ NCR_ProcessRxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_a
       return;
   }
 
+  if (limit == CLG_KOD) {
+    /* Don't respond if there is a conflict with the NTS NAK */
+    if (kod != 0)
+      return;
+    kod = KOD_RATE;
+  }
+
   local_ntp_rx = NULL;
   tx_ts = NULL;
   interleaved = 0;
@@ -2607,8 +2747,7 @@ NCR_ProcessRxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_a
       UTI_CompareNtp64(&message->receive_ts, &message->transmit_ts) != 0) {
     ntp_rx = message->originate_ts;
     local_ntp_rx = &ntp_rx;
-    UTI_ZeroTimespec(&local_tx.ts);
+    zero_local_timestamp(&local_tx);
-    local_tx.source = NTP_TS_DAEMON;
     interleaved = CLG_GetNtpTxTimestamp(&ntp_rx, &local_tx.ts, &local_tx.source);
 
     tx_ts = &local_tx;
@@ -2616,7 +2755,7 @@ NCR_ProcessRxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_a
       CLG_DisableNtpTimestamps(&ntp_rx);
   }
 
-  CLG_UpdateNtpStats(kod != 0 && info.auth.mode != NTP_AUTH_NONE &&
+  CLG_UpdateNtpStats(kod == 0 && info.auth.mode != NTP_AUTH_NONE &&
                      info.auth.mode != NTP_AUTH_MSSNTP,
                      rx_ts->source, interleaved ? tx_ts->source : NTP_TS_DAEMON);
 
@@ -2692,10 +2831,11 @@ NCR_ProcessTxKnown(NCR_Instance inst, NTP_Local_Address *local_addr,
                       message);
 
   if (tx_ts->source == NTP_TS_HARDWARE) {
-    inst->had_hw_tx_timestamp = 1;
+    inst->report.total_hw_tx_ts++;
-
     if (has_saved_response(inst))
       process_saved_response(inst);
+  } else if (tx_ts->source == NTP_TS_KERNEL) {
+    inst->report.total_kernel_tx_ts++;
   }
 }
 
@@ -2899,6 +3039,16 @@ NCR_ModifyMinstratum(NCR_Instance inst, int new_min_stratum)
 
 /* ================================================== */
 
+void
+NCR_ModifyOffset(NCR_Instance inst, double new_offset)
+{
+  inst->offset_correction = new_offset;
+  LOG(LOGS_INFO, "Source %s new offset %f",
+      UTI_IPToString(&inst->remote_addr.ip_addr), new_offset);
+}
+
+/* ================================================== */
+
 void
 NCR_ModifyPolltarget(NCR_Instance inst, int new_poll_target)
 {

ntp_core.h

@@ -42,6 +42,8 @@ typedef struct {
   struct timespec ts;
   double err;
   NTP_Timestamp_Source source;
+  double rx_duration;
+  double net_correction;
 } NTP_Local_Timestamp;
 
 /* This is a private data type used for storing the instance record for
@@ -111,6 +113,8 @@ extern void NCR_ModifyMaxdelaydevratio(NCR_Instance inst, double new_max_delay_d
 
 extern void NCR_ModifyMinstratum(NCR_Instance inst, int new_min_stratum);
 
+extern void NCR_ModifyOffset(NCR_Instance inst, double new_offset);
+
 extern void NCR_ModifyPolltarget(NCR_Instance inst, int new_poll_target);
 
 extern void NCR_InitiateSampleBurst(NCR_Instance inst, int n_good_samples, int n_total_samples);

ntp_io.c

@@ -278,6 +278,18 @@ NIO_Finalise(void)
 
 /* ================================================== */
 
+int
+NIO_IsHwTsEnabled(void)
+{
+#ifdef HAVE_LINUX_TIMESTAMPING
+  return NIO_Linux_IsHwTsEnabled();
+#else
+  return 0;
+#endif
+}
+
+/* ================================================== */
+
 int
 NIO_OpenClientSocket(NTP_Remote_Address *remote_addr)
 {
@@ -419,6 +431,9 @@ process_message(SCK_Message *message, int sock_fd, int event)
 
   SCH_GetLastEventTime(&local_ts.ts, &local_ts.err, NULL);
   local_ts.source = NTP_TS_DAEMON;
+  local_ts.rx_duration = 0.0;
+  local_ts.net_correction = 0.0;
+
   sched_ts = local_ts.ts;
 
   if (message->addr_type != SCK_ADDR_IP) {
@@ -444,7 +459,7 @@ process_message(SCK_Message *message, int sock_fd, int event)
     DEBUG_LOG("Updated RX timestamp delay=%.9f tss=%u",
               UTI_DiffTimespecsToDouble(&sched_ts, &local_ts.ts), local_ts.source);
 
-  if (!NIO_UnwrapMessage(message, sock_fd))
+  if (!NIO_UnwrapMessage(message, sock_fd, &local_ts.net_correction))
     return;
 
   /* Just ignore the packet if it's not of a recognized length */
@@ -483,8 +498,9 @@ read_from_socket(int sock_fd, int event, void *anything)
 /* ================================================== */
 
 int
-NIO_UnwrapMessage(SCK_Message *message, int sock_fd)
+NIO_UnwrapMessage(SCK_Message *message, int sock_fd, double *net_correction)
 {
+  double ptp_correction;
   PTP_NtpMessage *msg;
 
   if (!is_ptp_socket(sock_fd))
@@ -497,9 +513,11 @@ NIO_UnwrapMessage(SCK_Message *message, int sock_fd)
 
   msg = message->data;
 
-  if (msg->header.type != PTP_TYPE_DELAY_REQ || msg->header.version != PTP_VERSION ||
+  if ((msg->header.type != PTP_TYPE_DELAY_REQ && msg->header.type != PTP_TYPE_SYNC) ||
+      (msg->header.version != PTP_VERSION_2 &&
+       (msg->header.version != PTP_VERSION_2_1 || msg->header.min_sdoid != 0)) ||
       ntohs(msg->header.length) != message->length ||
-      msg->header.domain != PTP_DOMAIN_NTP ||
+      msg->header.domain != CNF_GetPtpDomain() ||
       ntohs(msg->header.flags) != PTP_FLAG_UNICAST ||
       ntohs(msg->tlv_header.type) != PTP_TLV_NTP ||
       ntohs(msg->tlv_header.length) != message->length - PTP_NTP_PREFIX_LENGTH) {
@@ -510,7 +528,14 @@ NIO_UnwrapMessage(SCK_Message *message, int sock_fd)
   message->data = (char *)message->data + PTP_NTP_PREFIX_LENGTH;
   message->length -= PTP_NTP_PREFIX_LENGTH;
 
-  DEBUG_LOG("Unwrapped PTP->NTP len=%d", message->length);
+  ptp_correction = UTI_Integer64NetworkToHost(*(Integer64 *)msg->header.correction) /
+                   ((1 << 16) * 1.0e9);
+
+  /* Use the correction only if the RX duration is known (i.e. HW timestamp) */
+  if (*net_correction > 0.0)
+    *net_correction += ptp_correction;
+
+  DEBUG_LOG("Unwrapped PTP->NTP len=%d corr=%.9f", message->length, ptp_correction);
 
   return 1;
 }
@@ -538,9 +563,9 @@ wrap_message(SCK_Message *message, int sock_fd)
 
   memset(ptp_message, 0, PTP_NTP_PREFIX_LENGTH);
   ptp_message->header.type = PTP_TYPE_DELAY_REQ;
-  ptp_message->header.version = PTP_VERSION;
+  ptp_message->header.version = PTP_VERSION_2;
   ptp_message->header.length = htons(PTP_NTP_PREFIX_LENGTH + message->length);
-  ptp_message->header.domain = PTP_DOMAIN_NTP;
+  ptp_message->header.domain = CNF_GetPtpDomain();
   ptp_message->header.flags = htons(PTP_FLAG_UNICAST);
   ptp_message->header.sequence_id = htons(sequence_id++);
   ptp_message->tlv_header.type = htons(PTP_TLV_NTP);

ntp_io.h

@@ -39,6 +39,9 @@ extern void NIO_Initialise(void);
 /* Function to finalise the module */
 extern void NIO_Finalise(void);
 
+/* Function to check if HW timestamping is enabled on any interface */
+extern int NIO_IsHwTsEnabled(void);
+
 /* Function to obtain a socket for sending client packets */
 extern int NIO_OpenClientSocket(NTP_Remote_Address *remote_addr);
 
@@ -61,7 +64,7 @@ extern int NIO_IsServerSocketOpen(void);
 extern int NIO_IsServerConnectable(NTP_Remote_Address *remote_addr);
 
 /* Function to unwrap an NTP message from non-native transport (e.g. PTP) */
-extern int NIO_UnwrapMessage(SCK_Message *message, int sock_fd);
+extern int NIO_UnwrapMessage(SCK_Message *message, int sock_fd, double *net_correction);
 
 /* Function to transmit a packet */
 extern int NIO_SendPacket(NTP_Packet *packet, NTP_Remote_Address *remote_addr,

ntp_io_linux.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2016-2019, 2021-2022
+ * Copyright (C) Miroslav Lichvar  2016-2019, 2021-2023
  * 
  * 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
@@ -439,6 +439,14 @@ NIO_Linux_Finalise(void)
 
 /* ================================================== */
 
+int
+NIO_Linux_IsHwTsEnabled(void)
+{
+  return ARR_GetSize(interfaces) > 0;
+}
+
+/* ================================================== */
+
 int
 NIO_Linux_SetTimestampSocketOptions(int sock_fd, int client_only, int *events)
 {
@@ -551,7 +559,7 @@ process_hw_timestamp(struct Interface *iface, struct timespec *hw_ts,
                      NTP_Local_Timestamp *local_ts, int rx_ntp_length, int family,
                      int l2_length)
 {
-  double rx_correction, ts_delay, local_err;
+  double rx_correction = 0.0, ts_delay, local_err;
   struct timespec ts;
 
   poll_phc(iface, &local_ts->ts);
@@ -592,6 +600,10 @@ process_hw_timestamp(struct Interface *iface, struct timespec *hw_ts,
   local_ts->ts = ts;
   local_ts->err = local_err;
   local_ts->source = NTP_TS_HARDWARE;
+  local_ts->rx_duration = rx_correction;
+  /* Network correction needs to include the RX duration to avoid
+     asymmetric correction with asymmetric link speeds */
+  local_ts->net_correction = rx_correction;
 }
 
 /* ================================================== */
@@ -715,6 +727,7 @@ NIO_Linux_ProcessMessage(SCK_Message *message, NTP_Local_Address *local_addr,
 {
   struct Interface *iface;
   int is_tx, ts_if_index, l2_length;
+  double c = 0.0;
 
   is_tx = event == SCH_FILE_EXCEPTION;
   iface = NULL;
@@ -775,7 +788,7 @@ NIO_Linux_ProcessMessage(SCK_Message *message, NTP_Local_Address *local_addr,
     return 1;
   }
 
-  if (!NIO_UnwrapMessage(message, local_addr->sock_fd))
+  if (!NIO_UnwrapMessage(message, local_addr->sock_fd, &c))
     return 1;
 
   if (message->length < NTP_HEADER_LENGTH || message->length > sizeof (NTP_Packet))

ntp_io_linux.h

@@ -33,6 +33,8 @@ extern void NIO_Linux_Initialise(void);
 
 extern void NIO_Linux_Finalise(void);
 
+extern int NIO_Linux_IsHwTsEnabled(void);
+
 extern int NIO_Linux_SetTimestampSocketOptions(int sock_fd, int client_only, int *events);
 
 extern int NIO_Linux_ProcessMessage(SCK_Message *message, NTP_Local_Address *local_addr,

ntp_signd.c

@@ -99,6 +99,9 @@ static int sock_fd;
 /* Flag indicating if the MS-SNTP authentication is enabled */
 static int enabled;
 
+/* Flag limiting logging of connection error messages */
+static int logged_connection_error;
+
 /* ================================================== */
 
 static void read_write_socket(int sock_fd, int event, void *anything);
@@ -134,6 +137,14 @@ open_socket(void)
   sock_fd = SCK_OpenUnixStreamSocket(path, NULL, 0);
   if (sock_fd < 0) {
     sock_fd = INVALID_SOCK_FD;
+
+    /* Log an error only once before a successful exchange to avoid
+       flooding the system log */
+    if (!logged_connection_error) {
+      LOG(LOGS_ERR, "Could not connect to signd socket %s : %s", path, strerror(errno));
+      logged_connection_error = 1;
+    }
+
     return 0;
   }
 
@@ -160,6 +171,8 @@ process_response(SignInstance *inst)
     return;
   }
 
+  logged_connection_error = 0;
+
   /* Check if the file descriptor is still valid */
   if (!NIO_IsServerSocket(inst->local_addr.sock_fd)) {
     DEBUG_LOG("Invalid NTP socket");

ntp_sources.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2011-2012, 2014, 2016, 2020-2021
+ * Copyright (C) Miroslav Lichvar  2011-2012, 2014, 2016, 2020-2024
  * 
  * 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
@@ -59,6 +59,10 @@ typedef struct {
   NCR_Instance data;            /* Data for the protocol engine for this source */
   char *name;                   /* Name of the source as it was specified
                                    (may be an IP address) */
+  IPAddr resolved_addr;         /* Address resolved from the name, which can be
+                                   different from remote_addr (e.g. NTS-KE) */
+  int family;                   /* IP family of acceptable resolved addresses
+                                   (IPADDR_UNSPEC if any) */
   int pool_id;                  /* ID of the pool from which was this source
                                    added or INVALID_POOL */
   int tentative;                /* Flag indicating there was no valid response
@@ -96,6 +100,8 @@ struct UnresolvedSource {
   int pool_id;
   /* Name to be resolved */
   char *name;
+  /* Address family to filter resolved addresses */
+  int family;
   /* Flag indicating addresses should be used in a random order */
   int random_order;
   /* Flag indicating current address should be replaced only if it is
@@ -213,8 +219,14 @@ NSR_Finalise(void)
   ARR_DestroyInstance(pools);
 
   SCH_RemoveTimeout(resolving_id);
-  while (unresolved_sources)
+
-    remove_unresolved_source(unresolved_sources);
+  /* Leave the unresolved sources allocated if the async resolver is running
+     to avoid reading the name from freed memory.  The handler will not be
+     called as the scheduler should no longer be running at this point. */
+  if (!resolving_source) {
+    while (unresolved_sources)
+      remove_unresolved_source(unresolved_sources);
+  }
 
   initialised = 0;
 }
@@ -351,7 +363,7 @@ log_source(SourceRecord *record, int addition, int once_per_pool)
 
 /* Procedure to add a new source */
 static NSR_Status
-add_source(NTP_Remote_Address *remote_addr, char *name, NTP_Source_Type type,
+add_source(NTP_Remote_Address *remote_addr, char *name, int family, NTP_Source_Type type,
            SourceParameters *params, int pool_id, uint32_t conf_id)
 {
   SourceRecord *record;
@@ -388,6 +400,8 @@ add_source(NTP_Remote_Address *remote_addr, char *name, NTP_Source_Type type,
       record->name = Strdup(name ? name : UTI_IPToString(&remote_addr->ip_addr));
       record->data = NCR_CreateInstance(remote_addr, type, params, record->name);
       record->remote_addr = NCR_GetRemoteAddress(record->data);
+      record->resolved_addr = remote_addr->ip_addr;
+      record->family = family;
       record->pool_id = pool_id;
       record->tentative = 1;
       record->conf_id = conf_id;
@@ -440,6 +454,8 @@ change_source_address(NTP_Remote_Address *old_addr, NTP_Remote_Address *new_addr
 
   record = get_record(slot1);
   NCR_ChangeRemoteAddress(record->data, new_addr, !replacement);
+  if (replacement)
+    record->resolved_addr = new_addr->ip_addr;
 
   if (record->remote_addr != NCR_GetRemoteAddress(record->data) ||
       UTI_CompareIPs(&record->remote_addr->ip_addr, &new_addr->ip_addr, NULL) != 0)
@@ -523,7 +539,7 @@ process_resolved_name(struct UnresolvedSource *us, IPAddr *ip_addrs, int n_addrs
   NTP_Remote_Address old_addr, new_addr;
   SourceRecord *record;
   unsigned short first = 0;
-  int i, j;
+  int i, j, slot;
 
   /* Keep using the current address if it is being refreshed and it is
      still included in the resolved addresses */
@@ -531,7 +547,8 @@ process_resolved_name(struct UnresolvedSource *us, IPAddr *ip_addrs, int n_addrs
     assert(us->pool_id == INVALID_POOL);
 
     for (i = 0; i < n_addrs; i++) {
-      if (UTI_CompareIPs(&us->address.ip_addr, &ip_addrs[i], NULL) == 0) {
+      if (find_slot2(&us->address, &slot) == 2 &&
+          UTI_CompareIPs(&get_record(slot)->resolved_addr, &ip_addrs[i], NULL) == 0) {
         DEBUG_LOG("%s still fresh", UTI_IPToString(&us->address.ip_addr));
         return;
       }
@@ -546,6 +563,10 @@ process_resolved_name(struct UnresolvedSource *us, IPAddr *ip_addrs, int n_addrs
 
     DEBUG_LOG("(%d) %s", i + 1, UTI_IPToString(&new_addr.ip_addr));
 
+    /* Skip addresses not from the requested family */
+    if (us->family != IPADDR_UNSPEC && us->family != new_addr.ip_addr.family)
+      continue;
+
     if (us->pool_id != INVALID_POOL) {
       /* In the pool resolving mode, try to replace a source from
          the pool which does not have a real address yet */
@@ -623,13 +644,16 @@ name_resolve_handler(DNS_Status status, int n_addrs, IPAddr *ip_addrs, void *any
   next = us->next;
 
   /* Don't repeat the resolving if it (permanently) failed, it was a
-     replacement of a real address, or all addresses are already resolved */
+     replacement of a real address, a refreshment, or all addresses are
-  if (status == DNS_Failure || UTI_IsIPReal(&us->address.ip_addr) || is_resolved(us))
+     already resolved */
+  if (status == DNS_Failure || UTI_IsIPReal(&us->address.ip_addr) ||
+      us->refreshment || is_resolved(us))
     remove_unresolved_source(us);
 
   /* If a restart was requested and this was the last source in the list,
      start with the first source again (if there still is one) */
   if (!next && resolving_restart) {
+    DEBUG_LOG("Restarting");
     next = unresolved_sources;
     resolving_restart = 0;
   }
@@ -694,11 +718,15 @@ static void
 append_unresolved_source(struct UnresolvedSource *us)
 {
   struct UnresolvedSource **i;
+  int n;
 
-  for (i = &unresolved_sources; *i; i = &(*i)->next)
+  for (i = &unresolved_sources, n = 0; *i; i = &(*i)->next, n++)
     ;
   *i = us;
   us->next = NULL;
+
+  DEBUG_LOG("Added unresolved source #%d pool_id=%d random=%d refresh=%d",
+            n + 1, us->pool_id, us->random_order, us->refreshment);
 }
 
 /* ================================================== */
@@ -748,8 +776,19 @@ static int get_unused_pool_id(void)
 static uint32_t
 get_next_conf_id(uint32_t *conf_id)
 {
+  SourceRecord *record;
+  unsigned int i;
+
+again:
   last_conf_id++;
 
+  /* Make sure the ID is not already used (after 32-bit wraparound) */
+  for (i = 0; i < ARR_GetSize(records); i++) {
+    record = get_record(i);
+    if (record->remote_addr && record->conf_id == last_conf_id)
+      goto again;
+  }
+
   if (conf_id)
     *conf_id = last_conf_id;
 
@@ -762,14 +801,14 @@ NSR_Status
 NSR_AddSource(NTP_Remote_Address *remote_addr, NTP_Source_Type type,
               SourceParameters *params, uint32_t *conf_id)
 {
-  return add_source(remote_addr, NULL, type, params, INVALID_POOL,
+  return add_source(remote_addr, NULL, IPADDR_UNSPEC, type, params, INVALID_POOL,
                     get_next_conf_id(conf_id));
 }
 
 /* ================================================== */
 
 NSR_Status
-NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type,
+NSR_AddSourceByName(char *name, int family, int port, int pool, NTP_Source_Type type,
                     SourceParameters *params, uint32_t *conf_id)
 {
   struct UnresolvedSource *us;
@@ -781,7 +820,9 @@ NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type,
   /* If the name is an IP address, add the source with the address directly */
   if (UTI_StringToIP(name, &remote_addr.ip_addr)) {
     remote_addr.port = port;
-    return add_source(&remote_addr, name, type, params, INVALID_POOL,
+    if (family != IPADDR_UNSPEC && family != remote_addr.ip_addr.family)
+      return NSR_InvalidAF;
+    return add_source(&remote_addr, name, IPADDR_UNSPEC, type, params, INVALID_POOL,
                       get_next_conf_id(conf_id));
   }
 
@@ -793,6 +834,7 @@ NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type,
 
   us = MallocNew(struct UnresolvedSource);
   us->name = Strdup(name);
+  us->family = family;
   us->random_order = 0;
   us->refreshment = 0;
 
@@ -829,7 +871,7 @@ NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type,
   for (i = 0; i < new_sources; i++) {
     if (i > 0)
       remote_addr.ip_addr.addr.id = ++last_address_id;
-    if (add_source(&remote_addr, name, type, params, us->pool_id, cid) != NSR_Success)
+    if (add_source(&remote_addr, name, family, type, params, us->pool_id, cid) != NSR_Success)
       return NSR_TooManySources;
   }
 
@@ -838,6 +880,31 @@ NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type,
 
 /* ================================================== */
 
+const char *
+NSR_StatusToString(NSR_Status status)
+{
+  switch (status) {
+    case NSR_Success:
+      return "Success";
+    case NSR_NoSuchSource:
+      return "No such source";
+    case NSR_AlreadyInUse:
+      return "Already in use";
+    case NSR_TooManySources:
+      return "Too many sources";
+    case NSR_InvalidAF:
+      return "Invalid address";
+    case NSR_InvalidName:
+      return "Invalid name";
+    case NSR_UnresolvedName:
+      return "Unresolved name";
+    default:
+      return "?";
+  }
+}
+
+/* ================================================== */
+
 void
 NSR_SetSourceResolvingEndHandler(NSR_SourceResolvingEndHandler handler)
 {
@@ -995,6 +1062,7 @@ resolve_source_replacement(SourceRecord *record, int refreshment)
 
   us = MallocNew(struct UnresolvedSource);
   us->name = Strdup(record->name);
+  us->family = record->family;
   /* Ignore the order of addresses from the resolver to not get
      stuck with a pair of unreachable or otherwise unusable servers
      (e.g. falsetickers) in case the order doesn't change, or a group
@@ -1005,7 +1073,10 @@ resolve_source_replacement(SourceRecord *record, int refreshment)
   us->address = *record->remote_addr;
 
   append_unresolved_source(us);
-  NSR_ResolveSources();
+
+  /* Don't restart resolving round if already running */
+  if (!resolving_source)
+    NSR_ResolveSources();
 }
 
 /* ================================================== */
@@ -1400,6 +1471,20 @@ NSR_ModifyMinstratum(IPAddr *address, int new_min_stratum)
 
 /* ================================================== */
 
+int
+NSR_ModifyOffset(IPAddr *address, double new_offset)
+{
+  int slot;
+
+  if (!find_slot(address, &slot))
+    return 0;
+
+  NCR_ModifyOffset(get_record(slot)->data, new_offset);
+  return 1;
+}
+
+/* ================================================== */
+
 int
 NSR_ModifyPolltarget(IPAddr *address, int new_poll_target)
 {

ntp_sources.h

@@ -55,11 +55,16 @@ extern NSR_Status NSR_AddSource(NTP_Remote_Address *remote_addr, NTP_Source_Type
 
 /* Procedure to add a new server, peer source, or pool of servers specified by
    name instead of address.  The name is resolved in exponentially increasing
-   intervals until it succeeds or fails with a non-temporary error.  If the
+   intervals until it succeeds or fails with a non-temporary error.  The
-   name is an address, it is equivalent to NSR_AddSource(). */
+   specified family filters resolved addresses.  If the name is an address
-extern NSR_Status NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type,
+   and its family does not conflict with the specified family, it is equivalent
+   to NSR_AddSource(). */
+extern NSR_Status NSR_AddSourceByName(char *name, int family, int port, int pool,
+                                      NTP_Source_Type type,
                                       SourceParameters *params, uint32_t *conf_id);
 
+extern const char *NSR_StatusToString(NSR_Status status);
+
 /* Function type for handlers to be called back when an attempt
  * (possibly unsuccessful) to resolve unresolved sources ends */
 typedef void (*NSR_SourceResolvingEndHandler)(void);
@@ -135,6 +140,8 @@ extern int NSR_ModifyMaxdelaydevratio(IPAddr *address, double new_max_delay_rati
 
 extern int NSR_ModifyMinstratum(IPAddr *address, int new_min_stratum);
 
+extern int NSR_ModifyOffset(IPAddr *address, double new_offset);
+
 extern int NSR_ModifyPolltarget(IPAddr *address, int new_poll_target);
 
 extern int NSR_InitiateSampleBurst(int n_good_samples, int n_total_samples, IPAddr *mask, IPAddr *address);

nts_ke.h

@@ -40,6 +40,7 @@
 #define NKE_RECORD_COOKIE               5
 #define NKE_RECORD_NTPV4_SERVER_NEGOTIATION 6
 #define NKE_RECORD_NTPV4_PORT_NEGOTIATION 7
+#define NKE_RECORD_COMPLIANT_128GCM_EXPORT 1024
 
 #define NKE_NEXT_PROTOCOL_NTPV4         0
 
@@ -49,8 +50,6 @@
 
 #define NKE_ALPN_NAME                   "ntske/1"
 #define NKE_EXPORTER_LABEL              "EXPORTER-network-time-security"
-#define NKE_EXPORTER_CONTEXT_C2S        "\x0\x0\x0\xf\x0"
-#define NKE_EXPORTER_CONTEXT_S2C        "\x0\x0\x0\xf\x1"
 
 #define NKE_MAX_MESSAGE_LENGTH          16384
 #define NKE_MAX_RECORD_BODY_LENGTH      256

nts_ke_client.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2020-2021
+ * Copyright (C) Miroslav Lichvar  2020-2021, 2024
  * 
  * 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
@@ -50,7 +50,9 @@ struct NKC_Instance_Record {
   int got_response;
   int resolving_name;
 
+  int compliant_128gcm;
   NKE_Context context;
+  NKE_Context alt_context;
   NKE_Cookie cookies[NKE_MAX_COOKIES];
   int num_cookies;
   char server_name[NKE_MAX_RECORD_BODY_LENGTH + 2];
@@ -98,12 +100,14 @@ name_resolve_handler(DNS_Status status, int n_addrs, IPAddr *ip_addrs, void *arg
 
 /* ================================================== */
 
+#define MAX_AEAD_ALGORITHMS 4
+
 static int
 prepare_request(NKC_Instance inst)
 {
   NKSN_Instance session = inst->session;
-  uint16_t data[2];
+  uint16_t data[MAX_AEAD_ALGORITHMS];
-  int length;
+  int i, aead_algorithm, length;
 
   NKSN_BeginMessage(session);
 
@@ -111,15 +115,24 @@ prepare_request(NKC_Instance inst)
   if (!NKSN_AddRecord(session, 1, NKE_RECORD_NEXT_PROTOCOL, data, sizeof (data[0])))
     return 0;
 
-  length = 0;
+  for (i = length = 0; i < ARR_GetSize(CNF_GetNtsAeads()) && length < MAX_AEAD_ALGORITHMS;
-  if (SIV_GetKeyLength(AEAD_AES_128_GCM_SIV) > 0)
+       i++) {
-    data[length++] = htons(AEAD_AES_128_GCM_SIV);
+    aead_algorithm = *(int *)ARR_GetElement(CNF_GetNtsAeads(), i);
-  if (SIV_GetKeyLength(AEAD_AES_SIV_CMAC_256) > 0)
+    if (SIV_GetKeyLength(aead_algorithm) > 0)
-    data[length++] = htons(AEAD_AES_SIV_CMAC_256);
+      data[length++] = htons(aead_algorithm);
+  }
   if (!NKSN_AddRecord(session, 1, NKE_RECORD_AEAD_ALGORITHM, data,
                       length * sizeof (data[0])))
     return 0;
 
+  for (i = 0; i < length; i++) {
+    if (data[i] == htons(AEAD_AES_128_GCM_SIV)) {
+      if (!NKSN_AddRecord(session, 0, NKE_RECORD_COMPLIANT_128GCM_EXPORT, NULL, 0))
+        return 0;
+      break;
+    }
+  }
+
   if (!NKSN_EndMessage(session))
     return 0;
 
@@ -139,6 +152,8 @@ process_response(NKC_Instance inst)
   assert(sizeof (data) % sizeof (uint16_t) == 0);
   assert(sizeof (uint16_t) == 2);
 
+  inst->compliant_128gcm = 0;
+  inst->alt_context.algorithm = AEAD_SIV_INVALID;
   inst->num_cookies = 0;
   inst->ntp_address.ip_addr.family = IPADDR_UNSPEC;
   inst->ntp_address.port = 0;
@@ -165,15 +180,31 @@ process_response(NKC_Instance inst)
         next_protocol = NKE_NEXT_PROTOCOL_NTPV4;
         break;
       case NKE_RECORD_AEAD_ALGORITHM:
-        if (length != 2 || (ntohs(data[0]) != AEAD_AES_SIV_CMAC_256 &&
+        if (length != 2) {
-                            ntohs(data[0]) != AEAD_AES_128_GCM_SIV) ||
+          DEBUG_LOG("Unexpected AEAD algorithm");
-            SIV_GetKeyLength(ntohs(data[0])) <= 0) {
-          DEBUG_LOG("Unexpected NTS-KE AEAD algorithm");
           error = 1;
           break;
         }
-        aead_algorithm = ntohs(data[0]);
+        for (i = 0; i < ARR_GetSize(CNF_GetNtsAeads()); i++) {
-        inst->context.algorithm = aead_algorithm;
+          if (ntohs(data[0]) == *(int *)ARR_GetElement(CNF_GetNtsAeads(), i) &&
+              SIV_GetKeyLength(ntohs(data[0])) > 0) {
+            aead_algorithm = ntohs(data[0]);
+            inst->context.algorithm = aead_algorithm;
+          }
+        }
+        if (aead_algorithm < 0) {
+          DEBUG_LOG("Unexpected AEAD algorithm");
+          error = 1;
+        }
+        break;
+      case NKE_RECORD_COMPLIANT_128GCM_EXPORT:
+        if (length != 0) {
+          DEBUG_LOG("Non-empty compliant-128gcm record");
+          error = 1;
+          break;
+        }
+        DEBUG_LOG("Compliant AES-128-GCM-SIV export");
+        inst->compliant_128gcm = 1;
         break;
       case NKE_RECORD_ERROR:
         if (length == 2)
@@ -255,6 +286,7 @@ process_response(NKC_Instance inst)
 static int
 handle_message(void *arg)
 {
+  SIV_Algorithm exporter_algorithm;
   NKC_Instance inst = arg;
 
   if (!process_response(inst)) {
@@ -262,8 +294,25 @@ handle_message(void *arg)
     return 0;
   }
 
-  if (!NKSN_GetKeys(inst->session, inst->context.algorithm,
+  exporter_algorithm = inst->context.algorithm;
-                    &inst->context.c2s, &inst->context.s2c))
+
+  /* With AES-128-GCM-SIV, set the algorithm ID in the RFC5705 key exporter
+     context incorrectly for compatibility with older chrony servers unless
+     the server confirmed support for the compliant context.  Generate both
+     sets of keys in case the server uses the compliant context, but does not
+     support the negotiation record, assuming it will respond with an NTS NAK
+     to a request authenticated with the noncompliant key. */
+  if (exporter_algorithm == AEAD_AES_128_GCM_SIV && !inst->compliant_128gcm) {
+    inst->alt_context.algorithm = inst->context.algorithm;
+    if (!NKSN_GetKeys(inst->session, inst->alt_context.algorithm, exporter_algorithm,
+                      NKE_NEXT_PROTOCOL_NTPV4, &inst->alt_context.c2s, &inst->alt_context.s2c))
+      return 0;
+
+    exporter_algorithm = AEAD_AES_SIV_CMAC_256;
+  }
+
+  if (!NKSN_GetKeys(inst->session, inst->context.algorithm, exporter_algorithm,
+                    NKE_NEXT_PROTOCOL_NTPV4, &inst->context.c2s, &inst->context.s2c))
     return 0;
 
   if (inst->server_name[0] != '\0') {
@@ -428,7 +477,7 @@ NKC_IsActive(NKC_Instance inst)
 /* ================================================== */
 
 int
-NKC_GetNtsData(NKC_Instance inst, NKE_Context *context,
+NKC_GetNtsData(NKC_Instance inst, NKE_Context *context, NKE_Context *alt_context,
                NKE_Cookie *cookies, int *num_cookies, int max_cookies,
                IPSockAddr *ntp_address)
 {
@@ -438,6 +487,7 @@ NKC_GetNtsData(NKC_Instance inst, NKE_Context *context,
     return 0;
 
   *context = inst->context;
+  *alt_context = inst->alt_context;
 
   for (i = 0; i < inst->num_cookies && i < max_cookies; i++)
     cookies[i] = inst->cookies[i];

nts_ke_client.h

@@ -46,7 +46,7 @@ extern int NKC_Start(NKC_Instance inst);
 extern int NKC_IsActive(NKC_Instance inst);
 
 /* Get the NTS data if the session was successful */
-extern int NKC_GetNtsData(NKC_Instance inst, NKE_Context *context,
+extern int NKC_GetNtsData(NKC_Instance inst, NKE_Context *context, NKE_Context *alt_context,
                           NKE_Cookie *cookies, int *num_cookies, int max_cookies,
                           IPSockAddr *ntp_address);
 

nts_ke_server.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2020
+ * Copyright (C) Miroslav Lichvar  2020, 2022, 2024
  * 
  * 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
@@ -242,7 +242,7 @@ accept_connection(int listening_fd, int event, void *arg)
   SCH_GetLastEventTime(&now, NULL, NULL);
 
   log_index = CLG_LogServiceAccess(CLG_NTSKE, &addr.ip_addr, &now);
-  if (log_index >= 0 && CLG_LimitServiceRate(CLG_NTSKE, log_index)) {
+  if (log_index >= 0 && CLG_LimitServiceRate(CLG_NTSKE, log_index) != CLG_PASS) {
     DEBUG_LOG("Rejected connection from %s (%s)",
               UTI_IPSockAddrToString(&addr), "rate limit");
     SCK_CloseSocket(sock_fd);
@@ -337,8 +337,10 @@ helper_signal(int x)
 /* ================================================== */
 
 static int
-prepare_response(NKSN_Instance session, int error, int next_protocol, int aead_algorithm)
+prepare_response(NKSN_Instance session, int error, int next_protocol, int aead_algorithm,
+                 int compliant_128gcm)
 {
+  SIV_Algorithm exporter_algorithm;
   NKE_Context context;
   NKE_Cookie cookie;
   char *ntp_server;
@@ -371,6 +373,11 @@ prepare_response(NKSN_Instance session, int error, int next_protocol, int aead_a
     if (!NKSN_AddRecord(session, 1, NKE_RECORD_AEAD_ALGORITHM, &datum, sizeof (datum)))
       return 0;
 
+    if (aead_algorithm == AEAD_AES_128_GCM_SIV && compliant_128gcm) {
+      if (!NKSN_AddRecord(session, 0, NKE_RECORD_COMPLIANT_128GCM_EXPORT, NULL, 0))
+        return 0;
+    }
+
     if (CNF_GetNTPPort() != NTP_PORT) {
       datum = htons(CNF_GetNTPPort());
       if (!NKSN_AddRecord(session, 1, NKE_RECORD_NTPV4_PORT_NEGOTIATION, &datum, sizeof (datum)))
@@ -385,8 +392,16 @@ prepare_response(NKSN_Instance session, int error, int next_protocol, int aead_a
     }
 
     context.algorithm = aead_algorithm;
+    exporter_algorithm = aead_algorithm;
 
-    if (!NKSN_GetKeys(session, aead_algorithm, &context.c2s, &context.s2c))
+    /* With AES-128-GCM-SIV, set the algorithm ID in the RFC5705 key exporter
+       context incorrectly for compatibility with older chrony clients unless
+       the client requested the compliant context */
+    if (exporter_algorithm == AEAD_AES_128_GCM_SIV && !compliant_128gcm)
+      exporter_algorithm = AEAD_AES_SIV_CMAC_256;
+
+    if (!NKSN_GetKeys(session, aead_algorithm, exporter_algorithm,
+                      NKE_NEXT_PROTOCOL_NTPV4, &context.c2s, &context.s2c))
       return 0;
 
     for (i = 0; i < NKE_MAX_COOKIES; i++) {
@@ -411,7 +426,8 @@ process_request(NKSN_Instance session)
   int next_protocol_records = 0, aead_algorithm_records = 0;
   int next_protocol_values = 0, aead_algorithm_values = 0;
   int next_protocol = -1, aead_algorithm = -1, error = -1;
-  int i, critical, type, length;
+  int i, j, critical, type, length;
+  int compliant_128gcm = 0;
   uint16_t data[NKE_MAX_RECORD_BODY_LENGTH / sizeof (uint16_t)];
 
   assert(NKE_MAX_RECORD_BODY_LENGTH % sizeof (uint16_t) == 0);
@@ -446,11 +462,21 @@ process_request(NKSN_Instance session)
 
         for (i = 0; i < MIN(length, sizeof (data)) / 2; i++) {
           aead_algorithm_values++;
-          /* Use the first supported algorithm */
+          /* Use the first enabled and supported algorithm */
-          if (aead_algorithm < 0 && SIV_GetKeyLength(ntohs(data[i])) > 0)
+          for (j = 0; j < ARR_GetSize(CNF_GetNtsAeads()); j++) {
-            aead_algorithm = ntohs(data[i]);
+            if (ntohs(data[i]) == *(int *)ARR_GetElement(CNF_GetNtsAeads(), j) &&
+                aead_algorithm < 0 && SIV_GetKeyLength(ntohs(data[i])) > 0)
+              aead_algorithm = ntohs(data[i]);
+          }
         }
         break;
+      case NKE_RECORD_COMPLIANT_128GCM_EXPORT:
+        if (length != 0) {
+          error = NKE_ERROR_BAD_REQUEST;
+          break;
+        }
+        compliant_128gcm = 1;
+        break;
       case NKE_RECORD_ERROR:
       case NKE_RECORD_WARNING:
       case NKE_RECORD_COOKIE:
@@ -469,7 +495,7 @@ process_request(NKSN_Instance session)
       error = NKE_ERROR_BAD_REQUEST;
   }
 
-  if (!prepare_response(session, error, next_protocol, aead_algorithm))
+  if (!prepare_response(session, error, next_protocol, aead_algorithm, compliant_128gcm))
     return 0;
 
   return 1;
@@ -651,7 +677,7 @@ load_keys(void)
 
   fclose(f);
 
-  LOG(LOGS_ERR, "Loaded %s", "server NTS keys");
+  LOG(LOGS_INFO, "Loaded %s", "server NTS keys");
   return 1;
 
 error:
@@ -685,6 +711,8 @@ run_helper(uid_t uid, gid_t gid, int scfilter_level)
 
   DEBUG_LOG("Helper started");
 
+  SCK_CloseReusableSockets();
+
   /* Suppress a log message about disabled clock control */
   log_severity = LOG_GetMinSeverity();
   LOG_SetMinSeverity(LOGS_ERR);

nts_ke_session.c

@@ -877,22 +877,42 @@ NKSN_GetRecord(NKSN_Instance inst, int *critical, int *type, int *body_length,
 /* ================================================== */
 
 int
-NKSN_GetKeys(NKSN_Instance inst, SIV_Algorithm siv, NKE_Key *c2s, NKE_Key *s2c)
+NKSN_GetKeys(NKSN_Instance inst, SIV_Algorithm algorithm, SIV_Algorithm exporter_algorithm,
+             int next_protocol, NKE_Key *c2s, NKE_Key *s2c)
 {
-  int length = SIV_GetKeyLength(siv);
+  int length = SIV_GetKeyLength(algorithm);
+  struct {
+    uint16_t next_protocol;
+    uint16_t algorithm;
+    uint8_t is_s2c;
+    uint8_t _pad;
+  } context;
+
+  if (!inst->tls_session)
+    return 0;
 
   if (length <= 0 || length > sizeof (c2s->key) || length > sizeof (s2c->key)) {
     DEBUG_LOG("Invalid algorithm");
     return 0;
   }
 
+  assert(sizeof (context) == 6);
+  context.next_protocol = htons(next_protocol);
+  context.algorithm = htons(exporter_algorithm);
+
+  context.is_s2c = 0;
   if (gnutls_prf_rfc5705(inst->tls_session,
                          sizeof (NKE_EXPORTER_LABEL) - 1, NKE_EXPORTER_LABEL,
-                         sizeof (NKE_EXPORTER_CONTEXT_C2S) - 1, NKE_EXPORTER_CONTEXT_C2S,
+                         sizeof (context) - 1, (char *)&context,
-                         length, (char *)c2s->key) < 0 ||
+                         length, (char *)c2s->key) < 0) {
-      gnutls_prf_rfc5705(inst->tls_session,
+    DEBUG_LOG("Could not export key");
+    return 0;
+  }
+
+  context.is_s2c = 1;
+  if (gnutls_prf_rfc5705(inst->tls_session,
                          sizeof (NKE_EXPORTER_LABEL) - 1, NKE_EXPORTER_LABEL,
-                         sizeof (NKE_EXPORTER_CONTEXT_S2C) - 1, NKE_EXPORTER_CONTEXT_S2C,
+                         sizeof (context) - 1, (char *)&context,
                          length, (char *)s2c->key) < 0) {
     DEBUG_LOG("Could not export key");
     return 0;

nts_ke_session.h

@@ -77,8 +77,11 @@ extern int NKSN_EndMessage(NKSN_Instance inst);
 extern int NKSN_GetRecord(NKSN_Instance inst, int *critical, int *type, int *body_length,
                           void *body, int buffer_length);
 
-/* Export NTS keys for a specified algorithm */
+/* Export NTS keys for a specified algorithm (for compatibility reasons the
-extern int NKSN_GetKeys(NKSN_Instance inst, SIV_Algorithm siv, NKE_Key *c2s, NKE_Key *s2c);
+   RFC5705 exporter context is allowed to have a different algorithm) */
+extern int NKSN_GetKeys(NKSN_Instance inst, SIV_Algorithm algorithm,
+                        SIV_Algorithm exporter_algorithm,
+                        int next_protocol, NKE_Key *c2s, NKE_Key *s2c);
 
 /* Check if the session has stopped */
 extern int NKSN_IsStopped(NKSN_Instance inst);

nts_ntp_client.c

@@ -72,6 +72,7 @@ struct NNC_Instance_Record {
   double last_nke_success;
 
   NKE_Context context;
+  NKE_Context alt_context;
   unsigned int context_id;
   NKE_Cookie cookies[NTS_MAX_COOKIES];
   int num_cookies;
@@ -105,6 +106,7 @@ reset_instance(NNC_Instance inst)
   inst->last_nke_success = 0.0;
 
   memset(&inst->context, 0, sizeof (inst->context));
+  memset(&inst->alt_context, 0, sizeof (inst->alt_context));
   inst->context_id = 0;
   memset(inst->cookies, 0, sizeof (inst->cookies));
   inst->num_cookies = 0;
@@ -165,6 +167,21 @@ check_cookies(NNC_Instance inst)
   if (inst->num_cookies > 0 &&
       ((inst->nak_response && !inst->ok_response) ||
        SCH_GetLastEventMonoTime() - inst->last_nke_success > CNF_GetNtsRefresh())) {
+
+    /* Before dropping the cookies, check whether there is an alternate set of
+       keys available (exported with the compliant context for AES-128-GCM-SIV)
+       and the NAK was the only valid response after the last NTS-KE session,
+       indicating we use incorrect keys and switching to the other set of keys
+       for the following NTP requests might work */
+    if (inst->alt_context.algorithm != AEAD_SIV_INVALID &&
+        inst->alt_context.algorithm == inst->context.algorithm &&
+        inst->nke_attempts > 0 && inst->nak_response && !inst->ok_response) {
+      inst->context = inst->alt_context;
+      inst->alt_context.algorithm = AEAD_SIV_INVALID;
+      DEBUG_LOG("Switched to compliant keys");
+      return 1;
+    }
+
     inst->num_cookies = 0;
     DEBUG_LOG("Dropped cookies");
   }
@@ -261,7 +278,7 @@ get_cookies(NNC_Instance inst)
   assert(sizeof (inst->cookies) / sizeof (inst->cookies[0]) == NTS_MAX_COOKIES);
 
   /* Get the new keys, cookies and NTP address if the session was successful */
-  got_data = NKC_GetNtsData(inst->nke, &inst->context,
+  got_data = NKC_GetNtsData(inst->nke, &inst->context, &inst->alt_context,
                             inst->cookies, &inst->num_cookies, NTS_MAX_COOKIES,
                             &ntp_address);
 
@@ -520,6 +537,7 @@ NNC_CheckResponseAuth(NNC_Instance inst, NTP_Packet *packet,
      new NTS-KE session to be started as soon as the cookies run out. */
   inst->nke_attempts = 0;
   inst->next_nke_attempt = 0.0;
+  inst->alt_context.algorithm = AEAD_SIV_INVALID;
 
   return 1;
 }
@@ -643,6 +661,7 @@ load_cookies(NNC_Instance inst)
         sscanf(words[0], "%u", &context_id) != 1 || sscanf(words[1], "%d", &algorithm) != 1)
     goto error;
 
+  inst->alt_context.algorithm = AEAD_SIV_INVALID;
   inst->context.algorithm = algorithm;
   inst->context.s2c.length = UTI_HexToBytes(words[2], inst->context.s2c.key,
                                             sizeof (inst->context.s2c.key));
@@ -687,6 +706,7 @@ error:
   fclose(f);
 
   memset(&inst->context, 0, sizeof (inst->context));
+  memset(&inst->alt_context, 0, sizeof (inst->alt_context));
   inst->num_cookies = 0;
 }
 

nts_ntp_server.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2020
+ * Copyright (C) Miroslav Lichvar  2020, 2022
  * 
  * 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
@@ -279,7 +279,7 @@ NNS_GenerateResponseAuth(NTP_Packet *request, NTP_PacketInfo *req_info,
   }
 
   /* NTS NAK response does not have any other fields */
-  if (kod)
+  if (kod == NTP_KOD_NTS_NAK)
     return 1;
 
   for (i = 0, plaintext_length = 0; i < server->num_cookies; i++) {

pktlength.c

@@ -111,7 +111,7 @@ static const struct request_length request_lengths[] = {
   REQ_LENGTH_ENTRY(null, null),                 /* REFRESH */
   REQ_LENGTH_ENTRY(null, server_stats),         /* SERVER_STATS */
   { 0, 0 },                                     /* CLIENT_ACCESSES_BY_INDEX2 - not supported */
-  REQ_LENGTH_ENTRY(local, null),                /* LOCAL2 */
+  { 0, 0 },                                     /* LOCAL2 - not supported */
   REQ_LENGTH_ENTRY(ntp_data, ntp_data),         /* NTP_DATA */
   { 0, 0 },                                     /* ADD_SERVER2 */
   { 0, 0 },                                     /* ADD_PEER2 */
@@ -130,6 +130,8 @@ static const struct request_length request_lengths[] = {
   REQ_LENGTH_ENTRY(null, null),                 /* RELOAD_SOURCES */
   REQ_LENGTH_ENTRY(doffset, null),              /* DOFFSET2 */
   REQ_LENGTH_ENTRY(modify_select_opts, null),   /* MODIFY_SELECTOPTS */
+  REQ_LENGTH_ENTRY(modify_offset, null),        /* MODIFY_OFFSET */
+  REQ_LENGTH_ENTRY(local, null),                /* LOCAL3 */
 };
 
 static const uint16_t reply_lengths[] = {
@@ -149,7 +151,7 @@ static const uint16_t reply_lengths[] = {
   RPY_LENGTH_ENTRY(smoothing),                  /* SMOOTHING */
   0,                                            /* SERVER_STATS - not supported */
   0,                                            /* CLIENT_ACCESSES_BY_INDEX2 - not supported */
-  RPY_LENGTH_ENTRY(ntp_data),                   /* NTP_DATA */
+  0,                                            /* NTP_DATA - not supported */
   RPY_LENGTH_ENTRY(manual_timestamp),           /* MANUAL_TIMESTAMP2 */
   RPY_LENGTH_ENTRY(manual_list),                /* MANUAL_LIST2 */
   RPY_LENGTH_ENTRY(ntp_source_name),            /* NTP_SOURCE_NAME */
@@ -159,6 +161,7 @@ static const uint16_t reply_lengths[] = {
   RPY_LENGTH_ENTRY(select_data),                /* SELECT_DATA */
   0,                                            /* SERVER_STATS3 - not supported */
   RPY_LENGTH_ENTRY(server_stats),               /* SERVER_STATS4 */
+  RPY_LENGTH_ENTRY(ntp_data),                   /* NTP_DATA2 */
 };
 
 /* ================================================== */

ptp.h

@@ -31,9 +31,10 @@
 
 #include "ntp.h"
 
-#define PTP_VERSION 2
+#define PTP_VERSION_2 2
+#define PTP_VERSION_2_1 (2 | 1 << 4)
+#define PTP_TYPE_SYNC 0
 #define PTP_TYPE_DELAY_REQ 1
-#define PTP_DOMAIN_NTP 123
 #define PTP_FLAG_UNICAST (1 << (2 + 8))
 #define PTP_TLV_NTP 0x2023
 

refclock.c

@@ -166,8 +166,8 @@ RCL_AddRefclock(RefclockParameters *params)
   if (!inst->driver->init && !inst->driver->poll)
     LOG_FATAL("refclock driver %s is not compiled in", params->driver_name);
 
-  if (params->tai && !CNF_GetLeapSecTimezone())
+  if (params->tai && !CNF_GetLeapSecList() && !CNF_GetLeapSecTimezone())
-    LOG_FATAL("refclock tai option requires leapsectz");
+    LOG_FATAL("refclock tai option requires leapseclist or leapsectz");
 
   inst->data = NULL;
   inst->driver_parameter = Strdup(params->driver_parameter);
@@ -321,6 +321,22 @@ RCL_ReportSource(RPT_SourceReport *report, struct timespec *now)
   }
 }
 
+int
+RCL_ModifyOffset(uint32_t ref_id, double offset)
+{
+  unsigned int i;
+
+  for (i = 0; i < ARR_GetSize(refclocks); i++) {
+    RCL_Instance inst = get_refclock(i);
+    if (inst->ref_id == ref_id) {
+      inst->offset = offset;
+      LOG(LOGS_INFO, "Source %s new offset %f", UTI_RefidToString(ref_id), offset);
+      return 1;
+    }
+  }
+  return 0;
+}
+
 void
 RCL_SetDriverData(RCL_Instance instance, void *data)
 {

refclock.h

@@ -68,6 +68,7 @@ extern void RCL_Finalise(void);
 extern int RCL_AddRefclock(RefclockParameters *params);
 extern void RCL_StartRefclocks(void);
 extern void RCL_ReportSource(RPT_SourceReport *report, struct timespec *now);
+extern int RCL_ModifyOffset(uint32_t ref_id, double offset);
 
 /* functions used by drivers */
 extern void RCL_SetDriverData(RCL_Instance instance, void *data);

refclock_phc.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2013, 2017
+ * Copyright (C) Miroslav Lichvar  2013, 2017, 2023
  * 
  * 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
@@ -175,7 +175,7 @@ static void read_ext_pulse(int fd, int event, void *anything)
   instance = anything;
   phc1 = RCL_GetDriverData(instance);
 
-  /* The Linux kernel (as of 6.2) has one shared queue of timestamps for all
+  /* Linux versions before 6.7 had one shared queue of timestamps for all
      descriptors of the same PHC.  Search for all refclocks that expect
      the timestamp. */
 

reference.c

@@ -4,6 +4,7 @@
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
  * Copyright (C) Miroslav Lichvar  2009-2018, 2020, 2022
+ * Copyright (C) Andy Fiddaman  2024
  * 
  * 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
@@ -33,6 +34,7 @@
 #include "reference.h"
 #include "util.h"
 #include "conf.h"
+#include "leapdb.h"
 #include "logging.h"
 #include "local.h"
 #include "sched.h"
@@ -53,6 +55,8 @@ static int enable_local_stratum;
 static int local_stratum;
 static int local_orphan;
 static double local_distance;
+static int local_activate_ok;
+static double local_activate;
 static struct timespec local_ref_time;
 static NTP_Leap our_leap_status;
 static int our_leap_sec;
@@ -122,9 +126,6 @@ static int leap_in_progress;
 /* Timer for the leap second handler */
 static SCH_TimeoutID leap_timeout_id;
 
-/* Name of a system timezone containing leap seconds occuring at midnight */
-static char *leap_tzname;
-
 /* ================================================== */
 
 static LOG_FileID logfileid;
@@ -155,7 +156,6 @@ static int ref_adjustments;
 
 /* ================================================== */
 
-static NTP_Leap get_tz_leap(time_t when, int *tai_offset);
 static void update_leap_status(NTP_Leap leap, time_t now, int reset);
 
 /* ================================================== */
@@ -195,7 +195,6 @@ REF_Initialise(void)
   FILE *in;
   double file_freq_ppm, file_skew_ppm;
   double our_frequency_ppm;
-  int tai_offset;
 
   mode = REF_ModeNormal;
   are_we_synchronised = 0;
@@ -211,6 +210,7 @@ REF_Initialise(void)
   our_frequency_sd = 0.0;
   our_offset_sd = 0.0;
   drift_file_age = 0.0;
+  local_activate_ok = 0;
 
   /* Now see if we can get the drift file opened */
   drift_file = CNF_GetDriftFile();
@@ -249,7 +249,8 @@ REF_Initialise(void)
 
   correction_time_ratio = CNF_GetCorrectionTimeRatio();
 
-  enable_local_stratum = CNF_AllowLocalReference(&local_stratum, &local_orphan, &local_distance);
+  enable_local_stratum = CNF_AllowLocalReference(&local_stratum, &local_orphan,
+                                                 &local_distance, &local_activate);
   UTI_ZeroTimespec(&local_ref_time);
 
   leap_when = 0;
@@ -260,18 +261,6 @@ REF_Initialise(void)
   if (leap_mode == REF_LeapModeSystem && !LCL_CanSystemLeap())
     leap_mode = REF_LeapModeStep;
 
-  leap_tzname = CNF_GetLeapSecTimezone();
-  if (leap_tzname) {
-    /* Check that the timezone has good data for Jun 30 2012 and Dec 31 2012 */
-    if (get_tz_leap(1341014400, &tai_offset) == LEAP_InsertSecond && tai_offset == 34 &&
-        get_tz_leap(1356912000, &tai_offset) == LEAP_Normal && tai_offset == 35) {
-      LOG(LOGS_INFO, "Using %s timezone to obtain leap second data", leap_tzname);
-    } else {
-      LOG(LOGS_WARN, "Timezone %s failed leap second check, ignoring", leap_tzname);
-      leap_tzname = NULL;
-    }
-  }
-
   CNF_GetMakeStep(&make_step_limit, &make_step_threshold);
   CNF_GetMaxChange(&max_offset_delay, &max_offset_ignore, &max_offset);
   CNF_GetMailOnChange(&do_mail_change, &mail_change_threshold, &mail_change_user);
@@ -593,77 +582,6 @@ is_leap_second_day(time_t when)
 
 /* ================================================== */
 
-static NTP_Leap
-get_tz_leap(time_t when, int *tai_offset)
-{
-  static time_t last_tz_leap_check;
-  static NTP_Leap tz_leap;
-  static int tz_tai_offset;
-
-  struct tm stm, *tm;
-  time_t t;
-  char *tz_env, tz_orig[128];
-
-  *tai_offset = tz_tai_offset;
-
-  /* Do this check at most twice a day */
-  when = when / (12 * 3600) * (12 * 3600);
-  if (last_tz_leap_check == when)
-      return tz_leap;
-
-  last_tz_leap_check = when;
-  tz_leap = LEAP_Normal;
-  tz_tai_offset = 0;
-
-  tm = gmtime(&when);
-  if (!tm)
-    return tz_leap;
-
-  stm = *tm;
-
-  /* Temporarily switch to the timezone containing leap seconds */
-  tz_env = getenv("TZ");
-  if (tz_env) {
-    if (strlen(tz_env) >= sizeof (tz_orig))
-      return tz_leap;
-    strcpy(tz_orig, tz_env);
-  }
-  setenv("TZ", leap_tzname, 1);
-  tzset();
-
-  /* Get the TAI-UTC offset, which started at the epoch at 10 seconds */
-  t = mktime(&stm);
-  if (t != -1)
-    tz_tai_offset = t - when + 10;
-
-  /* Set the time to 23:59:60 and see how it overflows in mktime() */
-  stm.tm_sec = 60;
-  stm.tm_min = 59;
-  stm.tm_hour = 23;
-
-  t = mktime(&stm);
-
-  if (tz_env)
-    setenv("TZ", tz_orig, 1);
-  else
-    unsetenv("TZ");
-  tzset();
-
-  if (t == -1)
-    return tz_leap;
-
-  if (stm.tm_sec == 60)
-    tz_leap = LEAP_InsertSecond;
-  else if (stm.tm_sec == 1)
-    tz_leap = LEAP_DeleteSecond;
-
-  *tai_offset = tz_tai_offset;
-
-  return tz_leap;
-}
-
-/* ================================================== */
-
 static void
 leap_end_timeout(void *arg)
 {
@@ -751,16 +669,16 @@ set_leap_timeout(time_t now)
 static void
 update_leap_status(NTP_Leap leap, time_t now, int reset)
 {
-  NTP_Leap tz_leap;
+  NTP_Leap ldb_leap;
   int leap_sec, tai_offset;
 
   leap_sec = 0;
   tai_offset = 0;
 
-  if (leap_tzname && now) {
+  if (now) {
-    tz_leap = get_tz_leap(now, &tai_offset);
+    ldb_leap = LDB_GetLeap(now, &tai_offset);
     if (leap == LEAP_Normal)
-      leap = tz_leap;
+      leap = ldb_leap;
   }
 
   if (leap == LEAP_InsertSecond || leap == LEAP_DeleteSecond) {
@@ -1219,7 +1137,7 @@ REF_GetReferenceParams
  double *root_dispersion
 )
 {
-  double dispersion, delta;
+  double dispersion, delta, distance;
 
   assert(initialised);
 
@@ -1229,11 +1147,16 @@ REF_GetReferenceParams
     dispersion = 0.0;
   }
 
+  distance = our_root_delay / 2 + dispersion;
+
+  if (local_activate == 0.0 || (are_we_synchronised && distance < local_activate))
+    local_activate_ok = 1;
+
   /* Local reference is active when enabled and the clock is not synchronised
      or the root distance exceeds the threshold */
 
   if (are_we_synchronised &&
-      !(enable_local_stratum && our_root_delay / 2 + dispersion > local_distance)) {
+      !(enable_local_stratum && local_activate_ok && distance > local_distance)) {
 
     *is_synchronised = 1;
 
@@ -1245,7 +1168,7 @@ REF_GetReferenceParams
     *root_delay = our_root_delay;
     *root_dispersion = dispersion;
 
-  } else if (enable_local_stratum) {
+  } else if (enable_local_stratum && local_activate_ok) {
 
     *is_synchronised = 0;
 
@@ -1345,12 +1268,13 @@ REF_ModifyMakestep(int limit, double threshold)
 /* ================================================== */
 
 void
-REF_EnableLocal(int stratum, double distance, int orphan)
+REF_EnableLocal(int stratum, double distance, int orphan, double activate)
 {
   enable_local_stratum = 1;
   local_stratum = CLAMP(1, stratum, NTP_MAX_STRATUM - 1);
   local_distance = distance;
   local_orphan = !!orphan;
+  local_activate = activate;
   LOG(LOGS_INFO, "%s local reference mode", "Enabled");
 }
 
@@ -1368,7 +1292,7 @@ REF_DisableLocal(void)
 #define LEAP_SECOND_CLOSE 5
 
 static int
-is_leap_close(time_t t)
+is_leap_close(double t)
 {
   return leap_when != 0 &&
          t >= leap_when - LEAP_SECOND_CLOSE && t < leap_when + LEAP_SECOND_CLOSE;
@@ -1398,7 +1322,7 @@ REF_GetTaiOffset(struct timespec *ts)
 {
   int tai_offset;
 
-  get_tz_leap(ts->tv_sec, &tai_offset);
+  LDB_GetLeap(ts->tv_sec, &tai_offset);
 
   return tai_offset;
 }

reference.h

@@ -185,7 +185,7 @@ extern void REF_ModifyMaxupdateskew(double new_max_update_skew);
 /* Modify makestep settings */
 extern void REF_ModifyMakestep(int limit, double threshold);
 
-extern void REF_EnableLocal(int stratum, double distance, int orphan);
+extern void REF_EnableLocal(int stratum, double distance, int orphan, double activate);
 extern void REF_DisableLocal(void);
 
 /* Check if either of the current raw and cooked time, and optionally a

regress.c

@@ -377,7 +377,7 @@ find_ordered_entry_with_flags(double *x, int n, int index, char *flags)
       r = v;
       do {
         while (l < v && x[l] < piv) l++;
-        while (x[r] > piv) r--;
+        while (r > 0 && x[r] > piv) r--;
         if (r <= l) break;
         EXCH(x[l], x[r]);
         l++;

reports.h

@@ -181,6 +181,10 @@ typedef struct {
   uint32_t total_rx_count;
   uint32_t total_valid_count;
   uint32_t total_good_count;
+  uint32_t total_kernel_tx_ts;
+  uint32_t total_kernel_rx_ts;
+  uint32_t total_hw_tx_ts;
+  uint32_t total_hw_rx_ts;
 } RPT_NTPReport;
 
 typedef struct {

rtc_linux.c

@@ -802,6 +802,7 @@ read_from_device(int fd_, int event, void *any)
     rtc_tm.tm_mday = rtc_raw.tm_mday;
     rtc_tm.tm_mon = rtc_raw.tm_mon;
     rtc_tm.tm_year = rtc_raw.tm_year;
+    rtc_tm.tm_wday = 0;
 
     rtc_t = t_from_rtc(&rtc_tm);
 

siv.h

@@ -36,6 +36,7 @@
 
 /* Identifiers of SIV algorithms following the IANA AEAD registry */
 typedef enum {
+  AEAD_SIV_INVALID = 0,
   AEAD_AES_SIV_CMAC_256 = 15,
   AEAD_AES_SIV_CMAC_384 = 16,
   AEAD_AES_SIV_CMAC_512 = 17,

siv_gnutls.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2020
+ * Copyright (C) Miroslav Lichvar  2020, 2023
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -37,6 +37,8 @@
 struct SIV_Instance_Record {
   gnutls_cipher_algorithm_t algorithm;
   gnutls_aead_cipher_hd_t cipher;
+  int min_nonce_length;
+  int max_nonce_length;
 };
 
 /* ================================================== */
@@ -81,6 +83,10 @@ get_cipher_algorithm(SIV_Algorithm algorithm)
   switch (algorithm) {
     case AEAD_AES_SIV_CMAC_256:
       return GNUTLS_CIPHER_AES_128_SIV;
+#if HAVE_GNUTLS_SIV_GCM
+    case AEAD_AES_128_GCM_SIV:
+      return GNUTLS_CIPHER_AES_128_SIV_GCM;
+#endif
     default:
       return 0;
   }
@@ -112,6 +118,19 @@ SIV_CreateInstance(SIV_Algorithm algorithm)
   instance->algorithm = calgo;
   instance->cipher = NULL;
 
+  switch (algorithm) {
+    case AEAD_AES_SIV_CMAC_256:
+      instance->min_nonce_length = 1;
+      instance->max_nonce_length = INT_MAX;
+      break;
+    case AEAD_AES_128_GCM_SIV:
+      instance->min_nonce_length = 12;
+      instance->max_nonce_length = 12;
+      break;
+    default:
+      assert(0);
+  }
+
   instance_counter++;
 
   return instance;
@@ -143,6 +162,8 @@ SIV_GetKeyLength(SIV_Algorithm algorithm)
     return 0;
 
   len = gnutls_cipher_get_key_size(calgo);
+  if (len == 0)
+    return 0;
 
   if (len < 1 || len > SIV_MAX_KEY_LENGTH)
     LOG_FATAL("Invalid key length");
@@ -198,7 +219,7 @@ SIV_SetKey(SIV_Instance instance, const unsigned char *key, int length)
 int
 SIV_GetMinNonceLength(SIV_Instance instance)
 {
-  return 1;
+  return instance->min_nonce_length;
 }
 
 /* ================================================== */
@@ -206,7 +227,7 @@ SIV_GetMinNonceLength(SIV_Instance instance)
 int
 SIV_GetMaxNonceLength(SIV_Instance instance)
 {
-  return INT_MAX;
+  return instance->max_nonce_length;
 }
 
 /* ================================================== */
@@ -238,7 +259,8 @@ SIV_Encrypt(SIV_Instance instance,
   if (!instance->cipher)
     return 0;
 
-  if (nonce_length < 1 || assoc_length < 0 ||
+  if (nonce_length < instance->min_nonce_length ||
+      nonce_length > instance->max_nonce_length || assoc_length < 0 ||
       plaintext_length < 0 || ciphertext_length < 0)
     return 0;
 
@@ -269,7 +291,8 @@ SIV_Decrypt(SIV_Instance instance,
   if (!instance->cipher)
     return 0;
 
-  if (nonce_length < 1 || assoc_length < 0 ||
+  if (nonce_length < instance->min_nonce_length ||
+      nonce_length > instance->max_nonce_length || assoc_length < 0 ||
       plaintext_length < 0 || ciphertext_length < 0)
     return 0;
 

siv_nettle.c

@@ -2,7 +2,7 @@
   chronyd/chronyc - Programs for keeping computer clocks accurate.
 
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2019
+ * Copyright (C) Miroslav Lichvar  2019, 2022
  * 
  * 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

socket.c

@@ -5,6 +5,7 @@
  * Copyright (C) Richard P. Curnow  1997-2003
  * Copyright (C) Timo Teras  2009
  * Copyright (C) Miroslav Lichvar  2009, 2013-2020
+ * Copyright (C) Luke Valenta  2023
  * 
  * 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
@@ -89,6 +90,9 @@ struct MessageHeader {
 
 static int initialised;
 
+static int first_reusable_fd;
+static int reusable_fds;
+
 /* Flags indicating in which IP families sockets can be requested */
 static int ip4_enabled;
 static int ip6_enabled;
@@ -155,6 +159,59 @@ domain_to_string(int domain)
 
 /* ================================================== */
 
+static int
+get_reusable_socket(int type, IPSockAddr *spec)
+{
+#ifdef LINUX
+  union sockaddr_all sa;
+  IPSockAddr ip_sa;
+  int sock_fd, opt;
+  socklen_t l;
+
+  /* Abort early if not an IPv4/IPv6 server socket */
+  if (!spec || spec->ip_addr.family == IPADDR_UNSPEC || spec->port == 0)
+    return INVALID_SOCK_FD;
+
+  /* Loop over available reusable sockets */
+  for (sock_fd = first_reusable_fd; sock_fd < first_reusable_fd + reusable_fds; sock_fd++) {
+
+    /* Check that types match */
+    l = sizeof (opt);
+    if (getsockopt(sock_fd, SOL_SOCKET, SO_TYPE, &opt, &l) < 0 ||
+        l != sizeof (opt) || opt != type)
+      continue;
+
+    /* Get sockaddr for reusable socket */
+    l = sizeof (sa);
+    if (getsockname(sock_fd, &sa.sa, &l) < 0 || l < sizeof (sa_family_t))
+      continue;
+    SCK_SockaddrToIPSockAddr(&sa.sa, l, &ip_sa);
+
+    /* Check that reusable socket matches specification */
+    if (ip_sa.port != spec->port || UTI_CompareIPs(&ip_sa.ip_addr, &spec->ip_addr, NULL) != 0)
+      continue;
+
+    /* Check that STREAM socket is listening */
+    l = sizeof (opt);
+    if (type == SOCK_STREAM && (getsockopt(sock_fd, SOL_SOCKET, SO_ACCEPTCONN, &opt, &l) < 0 ||
+                                l != sizeof (opt) || opt == 0))
+      continue;
+
+#if defined(FEAT_IPV6) && defined(IPV6_V6ONLY)
+    if (spec->ip_addr.family == IPADDR_INET6 &&
+        (!SCK_GetIntOption(sock_fd, IPPROTO_IPV6, IPV6_V6ONLY, &opt) || opt != 1))
+      LOG(LOGS_WARN, "Reusable IPv6 socket missing IPV6_V6ONLY option");
+#endif
+
+    return sock_fd;
+  }
+#endif
+
+  return INVALID_SOCK_FD;
+}
+
+/* ================================================== */
+
 #if defined(SOCK_CLOEXEC) || defined(SOCK_NONBLOCK)
 static int
 check_socket_flag(int sock_flag, int fd_flag, int fs_flag)
@@ -212,7 +269,7 @@ static int
 set_socket_flags(int sock_fd, int flags)
 {
   /* Close the socket automatically on exec */
-  if (
+  if (!SCK_IsReusable(sock_fd) &&
 #ifdef SOCK_CLOEXEC
       (supported_socket_flags & SOCK_CLOEXEC) == 0 &&
 #endif
@@ -222,7 +279,7 @@ set_socket_flags(int sock_fd, int flags)
   /* Enable non-blocking mode */
   if ((flags & SCK_FLAG_BLOCK) == 0 &&
 #ifdef SOCK_NONBLOCK
-      (supported_socket_flags & SOCK_NONBLOCK) == 0 &&
+      (SCK_IsReusable(sock_fd) || (supported_socket_flags & SOCK_NONBLOCK) == 0) &&
 #endif
       !set_socket_nonblock(sock_fd))
     return 0;
@@ -279,6 +336,32 @@ open_socket_pair(int domain, int type, int flags, int *other_fd)
 
 /* ================================================== */
 
+static int
+get_ip_socket(int domain, int type, int flags, IPSockAddr *ip_sa)
+{
+  int sock_fd;
+
+  /* Check if there is a matching reusable socket */
+  sock_fd = get_reusable_socket(type, ip_sa);
+
+  if (sock_fd < 0) {
+    sock_fd = open_socket(domain, type, flags);
+
+    /* Unexpected, but make sure the new socket is not in the reusable range */
+    if (SCK_IsReusable(sock_fd))
+      LOG_FATAL("Could not open %s socket : file descriptor in reusable range",
+                domain_to_string(domain));
+  } else {
+    /* Set socket flags on reusable socket */
+    if (!set_socket_flags(sock_fd, flags))
+      return INVALID_SOCK_FD;
+  }
+
+  return sock_fd;
+}
+
+/* ================================================== */
+
 static int
 set_socket_options(int sock_fd, int flags)
 {
@@ -295,8 +378,10 @@ static int
 set_ip_options(int sock_fd, int family, int flags)
 {
 #if defined(FEAT_IPV6) && defined(IPV6_V6ONLY)
-  /* Receive only IPv6 packets on an IPv6 socket */
+  /* Receive only IPv6 packets on an IPv6 socket, but do not attempt
-  if (family == IPADDR_INET6 && !SCK_SetIntOption(sock_fd, IPPROTO_IPV6, IPV6_V6ONLY, 1))
+     to set this option on pre-initialised reuseable sockets */
+  if (family == IPADDR_INET6 && !SCK_IsReusable(sock_fd) &&
+      !SCK_SetIntOption(sock_fd, IPPROTO_IPV6, IPV6_V6ONLY, 1))
     return 0;
 #endif
 
@@ -385,6 +470,10 @@ bind_ip_address(int sock_fd, IPSockAddr *addr, int flags)
     ;
 #endif
 
+  /* Do not attempt to bind pre-initialised reusable socket */
+  if (SCK_IsReusable(sock_fd))
+    return 1;
+
   saddr_len = SCK_IPSockAddrToSockaddr(addr, (struct sockaddr *)&saddr, sizeof (saddr));
   if (saddr_len == 0)
     return 0;
@@ -457,7 +546,7 @@ open_ip_socket(IPSockAddr *remote_addr, IPSockAddr *local_addr, const char *ifac
       return INVALID_SOCK_FD;
   }
 
-  sock_fd = open_socket(domain, type, flags);
+  sock_fd = get_ip_socket(domain, type, flags, local_addr);
   if (sock_fd < 0)
     return INVALID_SOCK_FD;
 
@@ -482,7 +571,8 @@ open_ip_socket(IPSockAddr *remote_addr, IPSockAddr *local_addr, const char *ifac
     goto error;
 
   if (remote_addr || local_addr)
-    DEBUG_LOG("Opened %s%s socket fd=%d%s%s%s%s",
+    DEBUG_LOG("%s %s%s socket fd=%d%s%s%s%s",
+              SCK_IsReusable(sock_fd) ? "Reusing" : "Opened",
               type == SOCK_DGRAM ? "UDP" : type == SOCK_STREAM ? "TCP" : "?",
               family == IPADDR_INET4 ? "v4" : "v6",
               sock_fd,
@@ -869,6 +959,11 @@ process_header(struct msghdr *msg, int msg_length, int sock_fd, int flags,
       memcpy(&message->timestamp.kernel, CMSG_DATA(cmsg), sizeof (message->timestamp.kernel));
     }
 #endif
+#ifdef SCM_REALTIME
+    else if (match_cmsg(cmsg, SOL_SOCKET, SCM_REALTIME, sizeof (message->timestamp.kernel))) {
+      memcpy(&message->timestamp.kernel, CMSG_DATA(cmsg), sizeof (message->timestamp.kernel));
+    }
+#endif
 #ifdef HAVE_LINUX_TIMESTAMPING
 #ifdef HAVE_LINUX_TIMESTAMPING_OPT_PKTINFO
     else if (match_cmsg(cmsg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
@@ -1165,9 +1260,44 @@ send_message(int sock_fd, SCK_Message *message, int flags)
 
 /* ================================================== */
 
+void
+SCK_PreInitialise(void)
+{
+#ifdef LINUX
+  char *s, *ptr;
+
+  /* On Linux systems, the systemd service manager may pass file descriptors
+     for pre-initialised sockets to the chronyd daemon.  The service manager
+     allocates and binds the file descriptors, and passes a copy to each
+     spawned instance of the service.  This allows for zero-downtime service
+     restarts as the sockets buffer client requests until the service is able
+     to handle them.  The service manager sets the LISTEN_FDS environment
+     variable to the number of passed file descriptors, and the integer file
+     descriptors start at 3 (see SD_LISTEN_FDS_START in
+     https://www.freedesktop.org/software/systemd/man/latest/sd_listen_fds.html). */
+  first_reusable_fd = 3;
+  reusable_fds = 0;
+
+  s = getenv("LISTEN_FDS");
+  if (s) {
+    errno = 0;
+    reusable_fds = strtol(s, &ptr, 10);
+    if (errno != 0 || *ptr != '\0' || reusable_fds < 0)
+      reusable_fds = 0;
+  }
+#else
+  first_reusable_fd = 0;
+  reusable_fds = 0;
+#endif
+}
+
+/* ================================================== */
+
 void
 SCK_Initialise(int family)
 {
+  int fd;
+
   ip4_enabled = family == IPADDR_INET4 || family == IPADDR_UNSPEC;
 #ifdef FEAT_IPV6
   ip6_enabled = family == IPADDR_INET6 || family == IPADDR_UNSPEC;
@@ -1196,6 +1326,9 @@ SCK_Initialise(int family)
     supported_socket_flags |= SOCK_NONBLOCK;
 #endif
 
+  for (fd = first_reusable_fd; fd < first_reusable_fd + reusable_fds; fd++)
+    UTI_FdSetCloexec(fd);
+
   initialised = 1;
 }
 
@@ -1208,6 +1341,8 @@ SCK_Finalise(void)
   ARR_DestroyInstance(recv_headers);
   ARR_DestroyInstance(recv_messages);
 
+  SCK_CloseReusableSockets();
+
   initialised = 0;
 }
 
@@ -1348,6 +1483,27 @@ SCK_OpenUnixSocketPair(int flags, int *other_fd)
 
 /* ================================================== */
 
+int
+SCK_IsReusable(int fd)
+{
+  return fd >= first_reusable_fd && fd < first_reusable_fd + reusable_fds;
+}
+
+/* ================================================== */
+
+void
+SCK_CloseReusableSockets(void)
+{
+  int fd;
+
+  for (fd = first_reusable_fd; fd < first_reusable_fd + reusable_fds; fd++)
+    close(fd);
+  reusable_fds = 0;
+  first_reusable_fd = 0;
+}
+
+/* ================================================== */
+
 int
 SCK_SetIntOption(int sock_fd, int level, int name, int value)
 {
@@ -1386,8 +1542,15 @@ SCK_EnableKernelRxTimestamping(int sock_fd)
     return 1;
 #endif
 #ifdef SO_TIMESTAMP
-  if (SCK_SetIntOption(sock_fd, SOL_SOCKET, SO_TIMESTAMP, 1))
+  if (SCK_SetIntOption(sock_fd, SOL_SOCKET, SO_TIMESTAMP, 1)) {
+#if defined(SO_TS_CLOCK) && defined(SO_TS_REALTIME)
+    /* We don't care about the return value - we'll get either a
+       SCM_REALTIME (if we succeded) or a SCM_TIMESTAMP (if we failed) */
+    if (!SCK_SetIntOption(sock_fd, SOL_SOCKET, SO_TS_CLOCK, SO_TS_REALTIME))
+      ;
+#endif
     return 1;
+  }
 #endif
 
   return 0;
@@ -1398,7 +1561,7 @@ SCK_EnableKernelRxTimestamping(int sock_fd)
 int
 SCK_ListenOnSocket(int sock_fd, int backlog)
 {
-  if (listen(sock_fd, backlog) < 0) {
+  if (!SCK_IsReusable(sock_fd) && listen(sock_fd, backlog) < 0) {
     DEBUG_LOG("listen() failed : %s", strerror(errno));
     return 0;
   }
@@ -1561,6 +1724,10 @@ SCK_RemoveSocket(int sock_fd)
 void
 SCK_CloseSocket(int sock_fd)
 {
+  /* Reusable sockets are closed in finalisation */
+  if (SCK_IsReusable(sock_fd))
+    return;
+
   close(sock_fd);
 }
 

socket.h

@@ -73,6 +73,9 @@ typedef struct {
   int descriptor;
 } SCK_Message;
 
+/* Pre-initialisation function */
+extern void SCK_PreInitialise(void);
+
 /* Initialisation function (the specified IP family is enabled,
    or all if IPADDR_UNSPEC) */
 extern void SCK_Initialise(int family);
@@ -106,6 +109,12 @@ extern int SCK_OpenUnixStreamSocket(const char *remote_addr, const char *local_a
                                     int flags);
 extern int SCK_OpenUnixSocketPair(int flags, int *other_fd);
 
+/* Check if a file descriptor was passed from the service manager */
+extern int SCK_IsReusable(int sock_fd);
+
+/* Close all reusable sockets before finalisation (e.g. in a helper process) */
+extern void SCK_CloseReusableSockets(void);
+
 /* Set and get a socket option of int size */
 extern int SCK_SetIntOption(int sock_fd, int level, int name, int value);
 extern int SCK_GetIntOption(int sock_fd, int level, int name, int *value);

sources.c

@@ -3,7 +3,7 @@
 
  **********************************************************************
  * Copyright (C) Richard P. Curnow  1997-2003
- * Copyright (C) Miroslav Lichvar  2011-2016, 2018, 2020-2021
+ * Copyright (C) Miroslav Lichvar  2011-2016, 2018, 2020-2024
  * 
  * 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
@@ -68,8 +68,8 @@ struct SelectInfo {
 typedef enum {
   SRC_OK,               /* OK so far, not a final status! */
   SRC_UNSELECTABLE,     /* Has noselect option set */
-  SRC_UNSYNCHRONISED,   /* Provides samples but not unsynchronised */
   SRC_BAD_STATS,        /* Doesn't have valid stats data */
+  SRC_UNSYNCHRONISED,   /* Provides samples, but not synchronised */
   SRC_BAD_DISTANCE,     /* Has root distance longer than allowed maximum */
   SRC_JITTERY,          /* Had std dev larger than allowed maximum */
   SRC_WAITS_STATS,      /* Others have bad stats, selection postponed */
@@ -174,6 +174,11 @@ static int selected_source_index; /* Which source index is currently
                                      if no current valid reference) */
 static int reported_no_majority;  /* Flag to avoid repeated log message
                                      about no majority */
+static int report_selection_loss; /* Flag to force logging a message if
+                                     selection is lost in a transient state
+                                     (SRC_WAITS_STATS, SRC_WAITS_UPDATE) */
+static int forced_first_report;   /* Flag to allow one failed selection to be
+                                     logged before a successful selection */
 
 /* Score needed to replace the currently selected source */
 #define SCORE_LIMIT 10.0
@@ -201,6 +206,8 @@ static LOG_FileID logfileid;
 /* Forward prototype */
 
 static void update_sel_options(void);
+static void unselect_selected_source(LOG_Severity severity, const char *format,
+                                     const char *arg);
 static void slew_sources(struct timespec *raw, struct timespec *cooked, double dfreq,
                          double doffset, LCL_ChangeType change_type, void *anything);
 static void add_dispersion(double dispersion, void *anything);
@@ -330,11 +337,12 @@ void SRC_DestroyInstance(SRC_Instance instance)
 
   update_sel_options();
 
-  /* If this was the previous reference source, we have to reselect! */
+  if (selected_source_index > dead_index)
-  if (selected_source_index == dead_index)
-    SRC_ReselectSource();
-  else if (selected_source_index > dead_index)
     --selected_source_index;
+  else if (selected_source_index == dead_index)
+    unselect_selected_source(LOGS_INFO, NULL, NULL);
+
+  SRC_SelectSource(NULL);
 }
 
 /* ================================================== */
@@ -357,6 +365,9 @@ SRC_ResetInstance(SRC_Instance instance)
   memset(&instance->sel_info, 0, sizeof (instance->sel_info));
 
   SST_ResetInstance(instance->stats);
+
+  if (selected_source_index == instance->index)
+    SRC_SelectSource(NULL);
 }
 
 /* ================================================== */
@@ -515,11 +526,6 @@ SRC_UpdateReachability(SRC_Instance inst, int reachable)
   if (inst->reachability_size < SOURCE_REACH_BITS)
       inst->reachability_size++;
 
-  if (!reachable && inst->index == selected_source_index) {
-    /* Try to select a better source */
-    SRC_SelectSource(NULL);
-  }
-
   /* Check if special reference update mode failed */
   if (REF_GetMode() != REF_ModeNormal && special_mode_end()) {
     REF_SetUnsynchronised();
@@ -528,6 +534,10 @@ SRC_UpdateReachability(SRC_Instance inst, int reachable)
   /* Try to replace unreachable NTP sources */
   if (inst->reachability == 0 && inst->reachability_size == SOURCE_REACH_BITS)
     handle_bad_source(inst);
+
+  /* Source selection can change with unreachable sources */
+  if (inst->reachability == 0)
+    SRC_SelectSource(NULL);
 }
 
 /* ================================================== */
@@ -587,18 +597,17 @@ update_sel_options(void)
   for (i = 0; i < n_sources; i++) {
     options = sources[i]->conf_sel_options;
 
-    if (options & SRC_SELECT_NOSELECT)
+    if (!(options & SRC_SELECT_NOSELECT)) {
-      continue;
+      switch (sources[i]->type) {
-
+        case SRC_NTP:
-    switch (sources[i]->type) {
+          options |= sources[i]->authenticated ? auth_ntp_options : unauth_ntp_options;
-      case SRC_NTP:
+          break;
-        options |= sources[i]->authenticated ? auth_ntp_options : unauth_ntp_options;
+        case SRC_REFCLOCK:
-        break;
+          options |= refclk_options;
-      case SRC_REFCLOCK:
+          break;
-        options |= refclk_options;
+        default:
-        break;
+          assert(0);
-      default:
+      }
-        assert(0);
     }
 
     if (sources[i]->sel_options != options) {
@@ -734,6 +743,26 @@ mark_ok_sources(SRC_Status status)
   }
 }
 
+/* ================================================== */
+/* Reset the index of selected source and report the selection loss.  If no
+   message is provided, assume it is a transient state and wait for another
+   call providing a message or selection of another source, which resets the
+   report_selection_loss flag. */
+
+static void
+unselect_selected_source(LOG_Severity severity, const char *format, const char *arg)
+{
+  if (selected_source_index != INVALID_SOURCE) {
+    selected_source_index = INVALID_SOURCE;
+    report_selection_loss = 1;
+  }
+
+  if (report_selection_loss && format) {
+    log_selection_message(severity, format, arg);
+    report_selection_loss = 0;
+  }
+}
+
 /* ================================================== */
 
 static int
@@ -834,7 +863,8 @@ SRC_SelectSource(SRC_Instance updated_inst)
   struct SelectInfo *si;
   struct timespec now, ref_time;
   int i, j, j1, j2, index, sel_prefer, n_endpoints, n_sel_sources, sel_req_source;
-  int n_badstats_sources, max_sel_reach, max_sel_reach_size, max_badstat_reach;
+  int max_badstat_reach, max_badstat_reach_size, n_badstats_sources;
+  int max_sel_reach, max_sel_reach_size;
   int depth, best_depth, trust_depth, best_trust_depth, n_sel_trust_sources;
   int combined, stratum, min_stratum, max_score_index;
   int orphan_stratum, orphan_source;
@@ -851,11 +881,7 @@ SRC_SelectSource(SRC_Instance updated_inst)
   }
 
   if (n_sources == 0) {
-    /* In this case, we clearly cannot synchronise to anything */
+    unselect_selected_source(LOGS_INFO, "Can't synchronise: no sources", NULL);
-    if (selected_source_index != INVALID_SOURCE) {
-      log_selection_message(LOGS_INFO, "Can't synchronise: no sources", NULL);
-      selected_source_index = INVALID_SOURCE;
-    }
     return;
   }
 
@@ -869,7 +895,7 @@ SRC_SelectSource(SRC_Instance updated_inst)
   n_badstats_sources = 0;
   sel_req_source = 0;
   max_sel_reach = max_badstat_reach = 0;
-  max_sel_reach_size = 0;
+  max_sel_reach_size = max_badstat_reach_size = 0;
   max_reach_sample_ago = 0.0;
 
   for (i = 0; i < n_sources; i++) {
@@ -889,12 +915,6 @@ SRC_SelectSource(SRC_Instance updated_inst)
       continue;
     }
 
-    /* Ignore sources which are not synchronised */
-    if (sources[i]->leap == LEAP_Unsynchronised) {
-      mark_source(sources[i], SRC_UNSYNCHRONISED);
-      continue;
-    }
-
     si = &sources[i]->sel_info;
     SST_GetSelectionData(sources[i]->stats, &now,
                          &si->lo_limit, &si->hi_limit, &si->root_distance,
@@ -906,6 +926,14 @@ SRC_SelectSource(SRC_Instance updated_inst)
       mark_source(sources[i], SRC_BAD_STATS);
       if (max_badstat_reach < sources[i]->reachability)
         max_badstat_reach = sources[i]->reachability;
+      if (max_badstat_reach_size < sources[i]->reachability_size)
+        max_badstat_reach_size = sources[i]->reachability_size;
+      continue;
+    }
+
+    /* Ignore sources which are not synchronised */
+    if (sources[i]->leap == LEAP_Unsynchronised) {
+      mark_source(sources[i], SRC_UNSYNCHRONISED);
       continue;
     }
 
@@ -1040,15 +1068,21 @@ SRC_SelectSource(SRC_Instance updated_inst)
   if (n_badstats_sources && n_sel_sources && selected_source_index == INVALID_SOURCE &&
       max_sel_reach_size < SOURCE_REACH_BITS && max_sel_reach >> 1 == max_badstat_reach) {
     mark_ok_sources(SRC_WAITS_STATS);
+    unselect_selected_source(LOGS_INFO, NULL, NULL);
     return;
   }
 
+  /* Wait for a source to have full reachability register to allow one
+     failed selection to be logged before first successful selection */
+  if (!forced_first_report &&
+      MAX(max_sel_reach_size, max_badstat_reach_size) == SOURCE_REACH_BITS) {
+    report_selection_loss = 1;
+    forced_first_report = 1;
+  }
+
   if (n_endpoints == 0) {
     /* No sources provided valid endpoints */
-    if (selected_source_index != INVALID_SOURCE) {
+    unselect_selected_source(LOGS_INFO, "Can't synchronise: no selectable sources", NULL);
-      log_selection_message(LOGS_INFO, "Can't synchronise: no selectable sources", NULL);
-      selected_source_index = INVALID_SOURCE;
-    }
     return;
   }
 
@@ -1129,6 +1163,7 @@ SRC_SelectSource(SRC_Instance updated_inst)
     if (!reported_no_majority) {
       log_selection_message(LOGS_WARN, "Can't synchronise: no majority", NULL);
       reported_no_majority = 1;
+      report_selection_loss = 0;
     }
 
     if (selected_source_index != INVALID_SOURCE) {
@@ -1185,12 +1220,9 @@ SRC_SelectSource(SRC_Instance updated_inst)
   }
 
   if (!n_sel_sources || sel_req_source || n_sel_sources < CNF_GetMinSources()) {
-    if (selected_source_index != INVALID_SOURCE) {
+    unselect_selected_source(LOGS_INFO, "Can't synchronise: %s selectable sources",
-      log_selection_message(LOGS_INFO, "Can't synchronise: %s selectable sources",
+                             !n_sel_sources ? "no" :
-                            !n_sel_sources ? "no" :
+                             sel_req_source ? "no required source in" : "not enough");
-                            sel_req_source ? "no required source in" : "not enough");
-      selected_source_index = INVALID_SOURCE;
-    }
     mark_ok_sources(SRC_WAITS_SOURCES);
     return;
   }
@@ -1297,7 +1329,7 @@ SRC_SelectSource(SRC_Instance updated_inst)
     /* Before selecting the new synchronisation source wait until the reference
        can be updated */
     if (sources[max_score_index]->updates == 0) {
-      selected_source_index = INVALID_SOURCE;
+      unselect_selected_source(LOGS_INFO, NULL, NULL);
       mark_ok_sources(SRC_WAITS_UPDATE);
       return;
     }
@@ -1313,6 +1345,8 @@ SRC_SelectSource(SRC_Instance updated_inst)
     }
 
     reported_no_majority = 0;
+    report_selection_loss = 0;
+    forced_first_report = 1;
   }
 
   mark_source(sources[selected_source_index], SRC_SELECTED);
@@ -1775,10 +1809,10 @@ get_status_char(SRC_Status status)
   switch (status) {
     case SRC_UNSELECTABLE:
       return 'N';
-    case SRC_UNSYNCHRONISED:
-      return 's';
     case SRC_BAD_STATS:
       return 'M';
+    case SRC_UNSYNCHRONISED:
+      return 's';
     case SRC_BAD_DISTANCE:
       return 'd';
     case SRC_JITTERY:

sourcestats.c

@@ -549,9 +549,9 @@ SST_DoNewRegression(SST_Stats inst)
         sd_weight += (peer_distances[i] - min_distance) / sd;
       weights[i] = SQUARE(sd_weight);
     }
-  }
 
-  correct_asymmetry(inst, times_back, offsets);
+    correct_asymmetry(inst, times_back, offsets);
+  }
 
   inst->regression_ok = RGR_FindBestRegression(times_back + inst->runs_samples,
                                          offsets + inst->runs_samples, weights,

stubs.c

@@ -201,12 +201,18 @@ NSR_AddSource(NTP_Remote_Address *remote_addr, NTP_Source_Type type,
 }
 
 NSR_Status
-NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type,
+NSR_AddSourceByName(char *name, int family, int port, int pool, NTP_Source_Type type,
                     SourceParameters *params, uint32_t *conf_id)
 {
   return NSR_TooManySources;
 }
 
+const char *
+NSR_StatusToString(NSR_Status status)
+{
+  return "NTP not supported";
+}
+
 NSR_Status
 NSR_RemoveSource(IPAddr *address)
 {
@@ -314,6 +320,12 @@ NSR_ModifyMinstratum(IPAddr *address, int new_min_stratum)
   return 0;
 }
 
+int
+NSR_ModifyOffset(IPAddr *address, double new_offset)
+{
+  return 0;
+}
+
 int
 NSR_ModifyPolltarget(IPAddr *address, int new_poll_target)
 {
@@ -413,6 +425,12 @@ RCL_ReportSource(RPT_SourceReport *report, struct timespec *now)
   memset(report, 0, sizeof (*report));
 }
 
+int
+RCL_ModifyOffset(uint32_t ref_id, double offset)
+{
+  return 0;
+}
+
 #endif /* !FEAT_REFCLOCK */
 
 #ifndef FEAT_SIGND

sys_linux.c

@@ -990,6 +990,14 @@ SYS_Linux_SetPHCExtTimestamping(int fd, int pin, int channel,
     return 0;
   }
 
+#if defined(PTP_MASK_CLEAR_ALL) && defined(PTP_MASK_EN_SINGLE)
+  /* Disable events from other channels on this descriptor */
+  if (ioctl(fd, PTP_MASK_CLEAR_ALL))
+    DEBUG_LOG("ioctl(%s) failed : %s", "PTP_MASK_CLEAR_ALL", strerror(errno));
+  else if (ioctl(fd, PTP_MASK_EN_SINGLE, &channel))
+    DEBUG_LOG("ioctl(%s) failed : %s", "PTP_MASK_EN_SINGLE", strerror(errno));
+#endif
+
   return 1;
 }
 

tempcomp.c

@@ -66,10 +66,9 @@ get_tempcomp(double temp)
     return k0 + (temp - T0) * k1 + (temp - T0) * (temp - T0) * k2;
 
   /* Otherwise interpolate/extrapolate between two nearest points */
-
+  for (i = 1; ; i++) {
-  for (i = 1; i < ARR_GetSize(points); i++) {
+    p2 = ARR_GetElement(points, i);
-    p2 = (struct Point *)ARR_GetElement(points, i);
+    if (p2->temp >= temp || i + 1 >= ARR_GetSize(points))
-    if (p2->temp >= temp)
       break;
   }
   p1 = p2 - 1;

test/compilation/002-scanbuild

@@ -3,13 +3,14 @@
 cd ../..
 
 for opts in \
+	"--enable-debug" \
 	"--host-system=Linux" \
 	"--host-system=NetBSD" \
 	"--host-system=FreeBSD" \
 	"--without-nettle" \
-	"--without-nettle --without-nss" \
+	"--without-nettle --without-gnutls" \
-	"--without-nettle --without-nss --without-tomcrypt" \
+	"--without-nettle --without-gnutls --without-nss" \
-	"--without-nettle --without-nss --without-tomcrypt --without-gnutls"
+	"--without-nettle --without-gnutls --without-nss --without-tomcrypt"
 do
 	./configure $opts
 	scan-build make "$@" || exit 1

test/compilation/003-sanitizers

@@ -25,13 +25,13 @@ touch Makefile
 for extra_config_opts in \
   "--all-privops" \
   "--disable-ipv6" \
+  "--disable-nts" \
   "--disable-scfilter" \
   "--without-aes-gcm-siv" \
-  "--without-gnutls" \
   "--without-nettle" \
-  "--without-nettle --without-nss" \
+  "--without-nettle --without-gnutls" \
-  "--without-nettle --without-nss --without-tomcrypt" \
+  "--without-nettle --without-gnutls --without-nss" \
-  "--without-nettle --without-nss --without-tomcrypt --without-gnutls"; \
+  "--without-nettle --without-gnutls --without-nss --without-tomcrypt"; \
 do
   for arch_opts in "-m32" ""; do
     pushd test/simulation/clknetsim || exit 1

test/simulation/008-ntpera

@@ -41,7 +41,6 @@ for time_offset in -1e-1 1e-1; do
 		export CLKNETSIM_START_DATE=$(awk "BEGIN {printf \"%.0f\", $ntp_start + $start_offset}")
 		run_test || test_fail
 		check_chronyd_exit || test_fail
-		check_source_selection || test_fail
 		check_packet_interval || test_fail
 		check_sync && test_fail
 	done

test/simulation/106-refclock

@@ -36,7 +36,7 @@ Update interval : 16\.. seconds
 .*$" || test_fail
 
 	if echo "$refclock" | grep -q 'PHC.*nocrossts'; then
-		check_file_messages "20.* GPS.*[0-9] N " 650 750 refclocks.log || test_fail
+		check_file_messages "20.* GPS.*[0-9] N " 620 750 refclocks.log || test_fail
 	else
 		check_file_messages "20.* GPS.*[0-9] N " 997 1001 refclocks.log || test_fail
 	fi
@@ -64,7 +64,7 @@ Stratum.*: 1
 Root delay      : 0\.000000001 seconds
 .*$" || test_fail
 
-	check_file_messages "20.* PPS1.*[0-9] N " 620 740 refclocks.log || test_fail
+	check_file_messages "20.* PPS1.*[0-9] N " 610 740 refclocks.log || test_fail
 	check_file_messages "20.* PPS1.*- N " 60 63 refclocks.log || test_fail
 	rm -f tmp/refclocks.log
 
@@ -89,14 +89,15 @@ Root delay      : 0\.000000001 seconds
 	check_file_messages "20.* PPS1.*- N " 60 63 refclocks.log || test_fail
 	rm -f tmp/refclocks.log
 
-	min_sync_time=100
+	min_sync_time=80
-	max_sync_time=220
+	max_sync_time=180
 	chronyc_start=220
 	client_conf="
 refclock SHM 0 refid NMEA offset 0.35 delay 0.1
 refclock PPS /dev/pps0
 logdir tmp
-log refclocks"
+log refclocks
+maxupdateskew 10000"
 
 	run_test || test_fail
 	check_chronyd_exit || test_fail
@@ -108,7 +109,7 @@ Stratum.*: 1
 Root delay      : 0\.000000001 seconds
 .*$" || test_fail
 
-	check_file_messages "20.* PPS1.*[0-9] N " 800 940  refclocks.log || test_fail
+	check_file_messages "20.* PPS1.*[0-9] N " 800 960  refclocks.log || test_fail
 	check_file_messages "20.* PPS1.*- N " 50 63 refclocks.log || test_fail
 	rm -f tmp/refclocks.log
 fi

test/simulation/108-peer

@@ -21,6 +21,7 @@ EOF
 
 clients=2
 peers=2
+freq_max_limit=1e-3
 max_sync_time=1000
 client_server_options="minpoll 6 maxpoll 6"
 client_peer_options="minpoll 6 maxpoll 6"
@@ -30,6 +31,7 @@ check_chronyd_exit || test_fail
 check_source_selection || test_fail
 check_sync || test_fail
 
+freq_max_limit=$default_freq_max_limit
 base_delay="(+ 1e-4 (* -1 (equal 0.1 from 3) (equal 0.1 to 1)))"
 client_peer_options=""
 

test/simulation/110-chronyc

@@ -58,7 +58,7 @@ MS Name/IP address         Stratum Poll Reach LastRx Last sample
 \^\? 192\.168\.123\.2                 0   [0-9]+     0     -     \+0ns\[   \+0ns\] \+/-    0ns
 Name/IP Address            NP  NR  Span  Frequency  Freq Skew  Offset  Std Dev
 ==============================================================================
-SHM0                       [0-9 ]+ [0-9 ]+ [0-9 ]+ [ +-][01]\.... [0-9 ]+\....  [0-9 +-]+[un]s [0-9 ]+[un]s
+SHM0                       [0-9 ]+ [0-9 ]+ [0-9 ]+ [ +-][012]\.... [0-9 ]+\....  [0-9 +-]+[un]s [0-9 ]+[un]s
 192\.168\.123\.1              [0-9 ]+ [0-9 ]+ [0-9 ]+ [ +-][01]\.... [0-9 ]+\....  [0-9 +-]+[un]s [0-9 ]+[un]s
 192\.168\.123\.2               0   0     0     \+0\.000   2000\.000     \+0ns  4000ms
 210 n_samples = 0
@@ -114,7 +114,7 @@ limit=1
 for chronyc_conf in \
 	"accheck 1.2.3.4" \
 	"add peer 10.0.0.0 minpoll 2 maxpoll 6" \
-	"add server 10.0.0.0 minpoll 6 maxpoll 10 iburst burst key 1 certset 2 maxdelay 1e-3 maxdelayratio 10.0 maxdelaydevratio 10.0 maxdelayquant 0.5 mindelay 1e-4 asymmetry 0.5 offset 1e-5 minsamples 6 maxsamples 6 filter 3 offline auto_offline prefer noselect trust require xleave polltarget 20 port 123 presend 7 minstratum 3 version 4 nts ntsport 4460 copy extfield F323" \
+	"add server 10.0.0.0 minpoll 6 maxpoll 10 iburst burst key 1 certset 2 maxdelay 1e-3 maxdelayratio 10.0 maxdelaydevratio 10.0 maxdelayquant 0.5 mindelay 1e-4 asymmetry 0.5 offset 1e-5 minsamples 6 maxsamples 6 filter 3 offline auto_offline prefer noselect trust require xleave polltarget 20 port 123 presend 7 minstratum 3 version 4 nts ntsport 4460 copy extfield F323 extfield F324 ipv6 ipv4" \
 	"add server node1.net1.clk" \
 	"allow 1.2.3.4" \
 	"allow 1.2" \
@@ -145,7 +145,7 @@ for chronyc_conf in \
 	"dfreq 1.0e-3" \
 	"doffset -1.0" \
 	"dump" \
-	"local stratum 5 distance 1.0 orphan" \
+	"local stratum 5 distance 1.0 activate 0.5 orphan" \
 	"local off" \
 	"makestep 10.0 3" \
 	"makestep" \
@@ -165,6 +165,7 @@ for chronyc_conf in \
 	"offline" \
 	"offline 255.255.255.0/1.2.3.0" \
 	"offline 1.2.3.0/24" \
+	"offset 1.2.3.4 1.0" \
 	"online" \
 	"online 1.2.3.0/24" \
 	"onoffline" \
@@ -247,6 +248,10 @@ Total TX        : 1
 Total RX        : 1
 Total valid RX  : 1
 Total good RX   : 0
+Total kernel TX : [01]
+Total kernel RX : 1
+Total HW TX     : 0
+Total HW RX     : 0
 S Name/IP Address        Auth COpts EOpts Last Score     Interval  Leap
 =======================================================================
 M node1\.net1\.clk            N ----- -----    0   1\.0    \+0ns    \+0ns  N
@@ -347,9 +352,12 @@ maxpoll 192.168.123.1 5
 maxupdateskew 192.168.123.1 10.0
 minpoll 192.168.123.1 3
 minstratum 192.168.123.1 1
+offset 192.168.123.1 -1.0
 polltarget 192.168.123.1 10
 selectopts 192.168.123.1 +trust +prefer -require
 selectdata
+selectopts 192.168.123.1 +noselect -prefer -trust +require
+selectdata
 delete 192.168.123.1"
 
 run_test || test_fail
@@ -369,9 +377,14 @@ check_chronyc_output "^200 OK
 200 OK
 200 OK
 200 OK
+200 OK
 S Name/IP Address        Auth COpts EOpts Last Score     Interval  Leap
 =======================================================================
 M node1\.net1\.clk            N \-PT\-\- \-PT\-\-    0   1\.0    \+0ns    \+0ns  \?
+200 OK
+S Name/IP Address        Auth COpts EOpts Last Score     Interval  Leap
+=======================================================================
+M node1\.net1\.clk            N N\-\-R\- N\-\-R\-    0   1\.0    \+0ns    \+0ns  \?
 200 OK$" || test_fail
 
 chronyc_conf="
@@ -427,7 +440,12 @@ server_conf="
 server 192.168.123.1
 noclientlog"
 
-commands=(
+check_config_h 'FEAT_IPV6 1' && commands=(
+	"add server ::1 ipv4" "^515 Invalid address family$"
+	) || commands=()
+
+commands+=(
+	"add server 192.168.123.1 ipv6" "^515 Invalid address family$"
 	"add server nosuchnode.net1.clk" "^Invalid host/IP address$"
 	"allow nosuchnode.net1.clk" "^Could not read address$"
 	"allow 192.168.123.0/2 4" "^Could not read address$"

test/simulation/113-leapsecond

@@ -8,54 +8,86 @@ check_config_h 'FEAT_REFCLOCK 1' || test_skip
 
 export CLKNETSIM_START_DATE=$(TZ=UTC date -d 'Dec 30 2008 0:00:00' +'%s')
 
-leap=$[2 * 24 * 3600]
 limit=$[4 * 24 * 3600]
 client_start=$[2 * 3600]
-server_conf="refclock SHM 0 dpoll 10 poll 10
-leapsectz right/UTC"
 refclock_jitter=1e-9
-refclock_offset="(* -1.0 (equal 0.1 (max (sum 1.0) $leap) $leap))"
 
-for leapmode in system step slew; do
+for dir in "+1" "-1"; do
-	client_conf="leapsecmode $leapmode"
+	leap=$[2 * 24 * 3600 + 1 + $dir]
-	if [ $leapmode = slew ]; then
-		max_sync_time=$[$leap + 12]
-	else
-		max_sync_time=$[$leap]
-	fi
-
-	run_test || test_fail
-	check_chronyd_exit || test_fail
-	check_source_selection || test_fail
-	check_packet_interval || test_fail
-	check_sync || test_fail
-done
-
-client_server_options="trust"
-client_conf="refclock SHM 0 dpoll 10 poll 10 delay 1e-3"
-
-run_test || test_fail
-check_chronyd_exit || test_fail
-check_source_selection || test_fail
-check_packet_interval || test_fail
-check_sync || test_fail
-
-client_server_options=""
-client_conf="leapsecmode system"
-min_sync_time=230000
-max_sync_time=240000
-
-for smoothmode in "" "leaponly"; do
 	server_conf="refclock SHM 0 dpoll 10 poll 10
-	leapsectz right/UTC
+	leapseclist tmp/leap.list"
-	leapsecmode slew
+	refclock_offset="(* $dir (equal 0.1 (max (sum 1.0) $leap) $leap))"
-	smoothtime 400 0.001 $smoothmode"
+
+	cat > tmp/leap.list <<-EOF
+		#$	3676924800
+		#@	3928521600
+		3345062400	33	# 1 Jan 2006
+		3439756800	$[33 - $dir]	# 1 Jan 2009 $(
+		[ "$dir" = "+1" ] && echo -e "\n3471292800	33\n3502828800	34")
+		3550089600	35	# 1 Jul 2012
+	EOF
+
+	for leapmode in system step slew; do
+		client_conf="leapsecmode $leapmode"
+		if [ $leapmode = slew ]; then
+			max_sync_time=$[2 * 24 * 3600 + 13]
+		else
+			max_sync_time=$[2 * 24 * 3600 + 1]
+		fi
+		min_sync_time=$[$max_sync_time - 2]
+
+		run_test || test_fail
+		check_chronyd_exit || test_fail
+		check_source_selection || test_fail
+		check_packet_interval || test_fail
+		check_sync || test_fail
+		check_file_messages "System clock TAI offset set to" 1 1 log.1 || test_fail
+		check_file_messages "System clock TAI offset set to 33" 1 1 log.1 || test_fail
+	done
+
+	client_server_options="trust"
+	client_conf="refclock SHM 0 dpoll 10 poll 10 delay 1e-3"
+	min_sync_time=$[$leap - 2]
+	max_sync_time=$[$leap]
 
 	run_test || test_fail
 	check_chronyd_exit || test_fail
 	check_source_selection || test_fail
 	check_packet_interval || test_fail
 	check_sync || test_fail
+
+	client_server_options=""
+	client_conf="leapsecmode system"
+	min_sync_time=230000
+	max_sync_time=240000
+
+	for smoothmode in "" "leaponly"; do
+		server_conf="refclock SHM 0 dpoll 10 poll 10
+		leapseclist tmp/leap.list
+		leapsecmode slew
+		smoothtime 400 0.001 $smoothmode"
+
+		run_test || test_fail
+		check_chronyd_exit || test_fail
+		check_source_selection || test_fail
+		check_packet_interval || test_fail
+		check_sync || test_fail
+	done
 done
 
+if TZ=right/UTC date -d 'Dec 31 2008 23:59:60' 2> /dev/null | grep :60; then
+	server_conf="refclock SHM 0 dpoll 10 poll 10
+	leapsectz right/UTC"
+	refclock_offset="(* -1 (equal 0.1 (max (sum 1.0) $leap) $leap))"
+	client_conf="leapsecmode system"
+	min_sync_time=$[$leap - 2]
+	max_sync_time=$[$leap]
+
+	run_test || test_fail
+	check_chronyd_exit || test_fail
+	check_source_selection || test_fail
+	check_packet_interval || test_fail
+	check_sync || test_fail
+fi
+
 test_pass

test/simulation/114-presend

@@ -3,6 +3,7 @@
 . ./test.common
 test_start "presend option"
 
+limit=9900
 min_sync_time=136
 max_sync_time=260
 client_server_options="presend 6 maxdelay 16"
@@ -22,4 +23,29 @@ check_source_selection || test_fail
 check_packet_interval || test_fail
 check_sync || test_fail
 
+limit=10
+base_delay=$default_base_delay
+client_conf="logdir tmp
+log measurements"
+
+client_server_options="presend 5"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_packet_interval || test_fail
+
+check_file_messages "20.*123\.1.* 111 111 0111" 1 1 measurements.log || test_fail
+check_file_messages "20.*123\.1.* 111 111 1111" 1 1 measurements.log || test_fail
+rm -f tmp/measurements.log
+
+client_server_options="presend 5 xleave"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_packet_interval || test_fail
+
+check_file_messages "20.*123\.1.* 111 111 0111" 2 2 measurements.log || test_fail
+check_file_messages "20.*123\.1.* 111 111 1111" 1 1 measurements.log || test_fail
+rm -f tmp/measurements.log
+
 test_pass

test/simulation/118-maxdelay

@@ -14,7 +14,6 @@ client_server_options="maxpoll 6 maxdelay 3e-5 maxdelayratio 2.0 maxdelaydevrati
 
 run_test || test_fail
 check_chronyd_exit || test_fail
-check_source_selection || test_fail
 check_packet_interval || test_fail
 check_sync || test_fail
 

test/simulation/119-smoothtime

@@ -14,7 +14,7 @@ max_sync_time=800
 
 run_test || test_fail
 check_chronyd_exit || test_fail
-check_source_selection || test_fail
+check_source_selection && test_fail
 check_sync || test_fail
 
 limit=10000

test/simulation/121-local

@@ -0,0 +1,90 @@
+#!/usr/bin/env bash
+
+. ./test.common
+
+test_start "local options"
+
+check_config_h 'FEAT_CMDMON 1' || test_skip
+
+server_strata=3
+server_conf="local stratum 5 orphan
+server 192.168.123.1
+server 192.168.123.2
+server 192.168.123.3"
+max_sync_time=900
+client_start=140
+chronyc_start=700
+chronyc_conf="tracking"
+time_rms_limit=5e-4
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_source_selection || test_fail
+check_sync || test_fail
+check_chronyc_output "^.*Stratum *: 7.*$" || test_fail
+
+limit=4000
+wander=0.0
+jitter=0.0
+server_strata=1
+server_conf=""
+client_server_options="minpoll 6 maxpoll 6 minsamples 64"
+chronyc_start=1
+chronyc_conf="timeout 1000000
+tracking
+tracking
+tracking
+tracking"
+base_delay=$(cat <<-EOF | tr -d '\n'
+  (+ 1e-4
+     (* 990
+        (equal 0.1 from 3))
+     (* -1
+        (equal 0.1 from 1)
+        (equal 0.1 (max (% time 2000) 1000) 1000)))
+EOF
+)
+
+client_conf="local
+maxclockerror 1000"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_chronyc_output "^.*7F7F0101.*C0A87B01.*7F7F0101.*C0A87B01.*$" || test_fail
+
+client_conf="local distance 0.5
+maxclockerror 1000"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_chronyc_output "^.*7F7F0101.*C0A87B01.*7F7F0101.*C0A87B01.*$" || test_fail
+
+client_conf="local distance 2.0
+maxclockerror 1000"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_chronyc_output "^.*7F7F0101.*C0A87B01.*C0A87B01.*C0A87B01.*$" || test_fail
+
+client_conf="local activate 1e-4
+maxclockerror 1000"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_chronyc_output "^.* 00000000 .*C0A87B01.*C0A87B01.*C0A87B01.*$" || test_fail
+
+client_conf="local activate 1e-1
+maxclockerror 1000"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_chronyc_output "^.* 00000000 .*C0A87B01.*7F7F0101.*C0A87B01.*$" || test_fail
+
+client_conf="local activate 1e-1 distance 2.0
+maxclockerror 1000"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_chronyc_output "^.* 00000000 .*C0A87B01.*C0A87B01.*C0A87B01.*$" || test_fail
+
+test_pass

test/simulation/121-orphan

@@ -1,26 +0,0 @@
-#!/usr/bin/env bash
-
-. ./test.common
-
-test_start "orphan option"
-
-check_config_h 'FEAT_CMDMON 1' || test_skip
-
-server_strata=3
-server_conf="local stratum 5 orphan
-server 192.168.123.1
-server 192.168.123.2
-server 192.168.123.3"
-max_sync_time=900
-client_start=140
-chronyc_start=700
-chronyc_conf="tracking"
-time_rms_limit=5e-4
-
-run_test || test_fail
-check_chronyd_exit || test_fail
-check_source_selection || test_fail
-check_sync || test_fail
-check_chronyc_output "^.*Stratum *: 7.*$" || test_fail
-
-test_pass

test/simulation/122-xleave

@@ -53,7 +53,6 @@ for rpoll in 4 5 6; do
 
 	run_test || test_fail
 	check_chronyd_exit || test_fail
-	check_source_selection || test_fail
 	check_sync || test_fail
 
 	if [ $rpoll -le 5 ]; then

test/simulation/124-tai

@@ -18,9 +18,17 @@ servers=0
 refclock_offset="(+ -34 (equal 0.1 (max (sum 1.0) $leap) $leap))"
 client_conf="
 refclock SHM 0 dpoll 0 poll 0 tai
-leapsectz right/UTC
+leapseclist tmp/leap.list
 leapsecmode ignore
-maxchange 1e-3 1 0"
+maxchange 1e-3 10 0"
+
+cat > tmp/leap.list <<-EOF
+	#$	3676924800
+	#@	3928521600
+	3345062400	33	# 1 Jan 2006
+	3439756800	34	# 1 Jan 2009
+	3550089600	35	# 1 Jul 2012
+EOF
 
 run_test || test_fail
 check_chronyd_exit || test_fail
@@ -33,9 +41,9 @@ time_offset=-1000
 refclock_offset="(+ -34)"
 client_conf="
 refclock SHM 0 dpoll 0 poll 0 tai
-leapsectz right/UTC
+leapseclist tmp/leap.list
 makestep 1 1
-maxchange 1e-3 1 0"
+maxchange 1e-3 10 0"
 
 run_test || test_fail
 check_chronyd_exit || test_fail

test/simulation/126-burst

@@ -22,7 +22,7 @@ client_min_mean_out_interval=150.0
 
 run_test || test_fail
 check_chronyd_exit || test_fail
-check_source_selection || test_fail
+check_source_selection && test_fail
 check_packet_interval || test_fail
 check_sync || test_fail
 

test/simulation/127-filter

@@ -12,7 +12,7 @@ client_min_mean_out_interval=15.9
 
 run_test || test_fail
 check_chronyd_exit || test_fail
-check_source_selection || test_fail
+check_source_selection && test_fail
 check_packet_interval || test_fail
 check_sync || test_fail
 

test/simulation/132-logchange

@@ -16,6 +16,6 @@ check_chronyd_exit || test_fail
 check_source_selection || test_fail
 check_packet_interval || test_fail
 check_sync || test_fail
-check_log_messages "clock wrong by" 4 8 || test_fail
+check_log_messages "clock wrong by" 3 8 || test_fail
 
 test_pass

test/simulation/135-ratelimit

@@ -15,4 +15,15 @@ check_sync || test_fail
 check_file_messages "	2	1	" 1200 1300 log.packets || test_fail
 check_file_messages "	1	2	" 180 220 log.packets || test_fail
 
+server_conf="ratelimit interval 6 burst 2 leak 4 kod 2"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_packet_interval || test_fail
+check_sync || test_fail
+
+check_file_messages "	2	1	" 700 850 log.packets || test_fail
+check_file_messages "	1	2	" 350 450 log.packets || test_fail
+check_log_messages "Received KoD RATE.*\.123.1" 100 140 || test_fail
+
 test_pass

test/simulation/139-nts

@@ -158,10 +158,10 @@ for dns in 1 0; do
 	check_source_selection && test_fail
 	check_sync && test_fail
 
-	check_file_messages "	2	1	.*	4460	" 50 100 log.packets || test_fail
+	check_file_messages "	2	1	.*	4460	" 45 100 log.packets || test_fail
 	check_file_messages "	2	2	.*	4460	" 0 0 log.packets || test_fail
 	check_log_messages "Source 192.168.123.1 changed to 192.168.123.2" 4 10 || test_fail
-	check_log_messages "Source 192.168.123.2 replaced with 192.168.123.1" 4 10 || test_fail
+	check_log_messages "Source 192.168.123.2 replaced with 192.168.123.1" 3 10 || test_fail
 
 	servers=2
 
@@ -225,6 +225,8 @@ for dns in 1 0; do
 	check_file_messages "	3	2	.*	4460	" 0 0 log.packets || test_fail
 done
 
+min_sync_time=$[default_min_sync_time + 200]
+max_sync_time=600
 server_conf="
 ntsserverkey tmp/server1.key
 ntsservercert tmp/server1.crt
@@ -248,6 +250,8 @@ check_file_messages "	3	2	.*	123	" 0 0 log.packets || test_fail
 check_file_messages "	3	2	.*	11123	" 3 3 log.packets || test_fail
 
 dns=1
+min_sync_time=$default_min_sync_time
+max_sync_time=400
 server_conf="
 ntsserverkey tmp/server1.key
 ntsservercert tmp/server1.crt
@@ -309,4 +313,31 @@ check_sync && test_fail
 check_file_messages "	3	1	.*	123	" 0 0 log.packets || test_fail
 check_file_messages "	3	2	.*	123	" 0 0 log.packets || test_fail
 
+for server_aead in "" "15" "30"; do
+	for client_aead in "" "15" "30"; do
+		server_conf="
+		ntsaeads $server_aead
+		ntsserverkey tmp/server1.key
+		ntsservercert tmp/server1.crt
+		ntsprocesses 0"
+		client_conf="
+		nosystemcert
+		ntsaeads $client_aead
+		ntstrustedcerts tmp/server1.crt
+		ntstrustedcerts tmp/server2.crt"
+		client_server_conf=""
+
+		run_test || test_fail
+		check_chronyd_exit || test_fail
+		if [ -n "$server_aead" ] && [ "$server_aead" == "$client_aead" ] &&
+		    ( [ "$server_aead" != "30" ] || check_config_h '.*_SIV_GCM 1' ); then
+			check_source_selection || test_fail
+			check_sync || test_fail
+		else
+			check_source_selection && test_fail
+			check_sync && test_fail
+		fi
+	done
+done
+
 test_pass

test/simulation/142-ntpoverptp

@@ -0,0 +1,123 @@
+#!/usr/bin/env bash
+
+. ./test.common
+
+test_start "NTP over PTP"
+
+# Block communication between 3 and 1
+base_delay="(+ 1e-4 (* -1 (equal 0.1 from 3) (equal 0.1 to 1)))"
+
+cat > tmp/peer.keys <<-EOF
+1 MD5 1234567890
+EOF
+
+clients=2
+peers=2
+max_sync_time=420
+
+server_conf="
+ptpdomain 123
+ptpport 319"
+client_conf="
+ptpport 319
+authselectmode ignore
+keyfile tmp/peer.keys"
+client_server_options="minpoll 6 maxpoll 6 port 319"
+client_peer_options="minpoll 6 maxpoll 6 port 319 key 1"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_source_selection || test_fail
+check_sync || test_fail
+
+check_file_messages "	2	1	.*	319	319	1	96	" 150 160 \
+	log.packets || test_fail
+check_file_messages "	1	2	.*	319	319	1	96	" 150 160 \
+	log.packets || test_fail
+check_file_messages "	2	3	.*	319	319	1	116	" 150 160 \
+	log.packets || test_fail
+check_file_messages "	3	2	.*	319	319	1	116	" 150 160 \
+	log.packets || test_fail
+
+check_config_h 'HAVE_LINUX_TIMESTAMPING 1' || test_skip
+
+export CLKNETSIM_TIMESTAMPING=2
+export CLKNETSIM_LINK_SPEED=100
+
+client_server_options+=" extfield F324 minpoll 0 maxpoll 0"
+client_peer_options+=" extfield F324 minpoll 0 maxpoll 0 maxdelaydevratio 1e6"
+server_conf+="
+clockprecision 1e-9
+hwtimestamp eth0"
+client_conf+="
+clockprecision 1e-9
+hwtimestamp eth0"
+delay_correction="(+ delay (* -8e-8 (+ length 46)))"
+wander=1e-9
+limit=1000
+freq_offset=-1e-4
+min_sync_time=5
+max_sync_time=20
+time_max_limit=1e-7
+time_rms_limit=2e-8
+freq_max_limit=1e-7
+freq_rms_limit=5e-8
+client_chronyd_options="-d"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_source_selection || test_fail
+check_sync || test_fail
+
+if check_config_h 'FEAT_DEBUG 1'; then
+	check_log_messages "apply_net_correction.*Applied" 900 2100 || test_fail
+	check_log_messages "apply_net_correction.*Invalid" 0 4 || test_fail
+fi
+
+client_server_options+=" xleave"
+client_peer_options+=" xleave"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_source_selection || test_fail
+check_sync || test_fail
+
+if check_config_h 'FEAT_DEBUG 1'; then
+	check_log_messages "apply_net_correction.*Applied" 900 2100 || test_fail
+	check_log_messages "apply_net_correction.*Invalid" 0 4 || test_fail
+
+	freq_offset=0.0
+	delay_correction="(+ -1.0e-9 (* 1.0001 delay))"
+
+	run_test || test_fail
+	check_chronyd_exit || test_fail
+
+	check_log_messages "apply_net_correction.*Applied" 350 1400 || test_fail
+	check_log_messages "apply_net_correction.*Invalid" 350 1400 || test_fail
+
+	server_conf="ptpport 319"
+	client_conf="ptpport 319"
+
+	run_test || test_fail
+	check_chronyd_exit || test_fail
+
+	check_log_messages "apply_net_correction.*Applied" 0 0 || test_fail
+fi
+
+freq_offset=-1e-4
+delay_correction=""
+server_conf="ptpport 319"
+client_conf="ptpport 319
+ptpdomain 124
+authselectmode ignore
+keyfile tmp/peer.keys"
+time_max_limit=$default_time_max_limit
+time_rms_limit=$default_time_rms_limit
+freq_max_limit=$default_freq_max_limit
+freq_rms_limit=$default_freq_rms_limit
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_sync && test_fail
+
+test_pass

test/simulation/142-ptpport

@@ -1,41 +0,0 @@
-#!/usr/bin/env bash
-
-. ./test.common
-
-test_start "PTP port"
-
-# Block communication between 3 and 1
-base_delay="(+ 1e-4 (* -1 (equal 0.1 from 3) (equal 0.1 to 1)))"
-
-cat > tmp/peer.keys <<-EOF
-1 MD5 1234567890
-EOF
-
-clients=2
-peers=2
-max_sync_time=420
-
-server_conf="
-ptpport 319"
-client_conf="
-ptpport 319
-authselectmode ignore
-keyfile tmp/peer.keys"
-client_server_options="minpoll 6 maxpoll 6 port 319"
-client_peer_options="minpoll 6 maxpoll 6 port 319 key 1"
-
-run_test || test_fail
-check_chronyd_exit || test_fail
-check_source_selection || test_fail
-check_sync || test_fail
-
-check_file_messages "	2	1	.*	319	319	1	96	" 150 160 \
-	log.packets || test_fail
-check_file_messages "	1	2	.*	319	319	1	96	" 150 160 \
-	log.packets || test_fail
-check_file_messages "	2	3	.*	319	319	1	116	" 150 160 \
-	log.packets || test_fail
-check_file_messages "	3	2	.*	319	319	1	116	" 150 160 \
-	log.packets || test_fail
-
-test_pass

test/simulation/144-monoroot

@@ -2,7 +2,7 @@
 
 . ./test.common
 
-test_start "experimental extension field"
+test_start "mono+root extension field"
 
 check_config_h 'FEAT_CMDMON 1' || test_skip
 
@@ -20,7 +20,7 @@ for options in "extfield F323" "xleave extfield F323"; do
 
 	run_test || test_fail
 	check_chronyd_exit || test_fail
-	check_source_selection || test_fail
+	check_source_selection && test_fail
 	check_sync || test_fail
 done
 
@@ -47,7 +47,7 @@ for lpoll in 5 6 7; do
 
 		run_test || test_fail
 		check_chronyd_exit || test_fail
-		check_source_selection || test_fail
+		check_source_selection && test_fail
 		check_sync || test_fail
 	done
 done

test/simulation/148-replacement

@@ -23,7 +23,7 @@ check_sync || test_fail
 
 check_log_messages "Detected falseticker" 2 10 || test_fail
 check_log_messages "Source 192.168.123.. replaced with" 1 3 || test_fail
-check_file_messages "20.*192.168.123.* 11.1   6  6 " 15 17 measurements.log || test_fail
+check_file_messages "20.*192.168.123.* 11.1   6  6 " 15 18 measurements.log || test_fail
 check_file_messages "20.*00:[1-5].:.. 192.168.123.* 11.1   6  6 " 1 4 measurements.log || test_fail
 rm -f tmp/measurements.log
 
@@ -53,4 +53,28 @@ check_log_messages "2010-01-01T0[5-9]:.*Source 192.168.123.. replaced with" 0 15
 check_file_messages "20.*192.168.123.* 11.1   6  6 " 20 500 measurements.log || test_fail
 rm -f tmp/measurements.log
 
+# 2 replaceable falsetickers and 1 replaceable unreachable server
+servers=6
+falsetickers=2
+base_delay="(+ 1e-4 (* -1 (equal 0.1 to 3)))"
+client_server_conf="
+server nodes-4-1.net1.clk
+server nodes-5-2.net1.clk
+server nodes-6-3.net1.clk"
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_source_selection && test_fail
+check_packet_interval || test_fail
+check_sync || test_fail
+
+check_log_messages "Can't synchronise: no majority" 1 1 || test_fail
+check_log_messages "Detected falseticker" 0 2 || test_fail
+check_log_messages "Source 192.168.123.. replaced with" 3 60 || test_fail
+check_log_messages "Source 192.168.123.1 replaced with" 1 25 || test_fail
+check_log_messages "Source 192.168.123.2 replaced with" 1 25 || test_fail
+check_log_messages "Source 192.168.123.3 replaced with" 1 25 || test_fail
+check_file_messages "20.*192.168.123.* 11.1   6  6 " 50 800 measurements.log || test_fail
+rm -f tmp/measurements.log
+
 test_pass

test/simulation/203-initreload

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+
+. ./test.common
+
+check_config_h 'FEAT_CMDMON 1' || test_skip
+
+# Test fix "conf: don't load sourcedir during initstepslew and RTC init"
+
+test_start "reload during initstepslew"
+
+client_conf="initstepslew 5 192.168.123.1
+sourcedir tmp"
+client_server_conf="#"
+chronyc_conf="reload sources"
+chronyc_start=4
+
+echo 'server 192.168.123.1' > tmp/sources.sources
+
+run_test || test_fail
+check_chronyd_exit || test_fail
+check_source_selection || test_fail
+check_sync || test_fail
+
+check_log_messages "Added source 192\.168\.123\.1" 1 1 || test_fail
+
+test_pass

test/simulation/test.common

@@ -31,6 +31,7 @@ default_primary_time_offset=0.0
 default_time_offset=1e-1
 default_freq_offset=1e-4
 default_base_delay=1e-4
+default_delay_correction=""
 default_jitter=1e-4
 default_jitter_asymmetry=0.0
 default_wander=1e-9
@@ -460,6 +461,10 @@ run_test() {
 		for j in $(seq 1 $nodes); do
 			echo "node${i}_delay${j} = $(get_delay_expr up)"
 			echo "node${j}_delay${i} = $(get_delay_expr down)"
+			if [ -n "$delay_correction" ]; then
+				echo "node${i}_delay_correction${j} = $delay_correction"
+				echo "node${j}_delay_correction${i} = $delay_correction"
+			fi
 		done
 	done > tmp/conf
 

test/system/007-cmdmon

@@ -28,6 +28,7 @@ for command in \
 	"local" \
 	"online" \
 	"onoffline" \
+	"offset $server 0.0" \
 	"maxdelay $server 1e-1" \
 	"maxdelaydevratio $server 5.0" \
 	"maxdelayratio $server 3.0" \
@@ -97,12 +98,16 @@ RX timestamping : (Daemon|Kernel)
 Total TX        : [0-9]+
 Total RX        : [0-9]+
 Total valid RX  : [0-9]+
-Total good RX   : [0-9]+$" || test_fail
+Total good RX   : [0-9]+
+Total kernel TX : [0-9]+
+Total kernel RX : [0-9]+
+Total HW TX     : 0
+Total HW RX     : 0$" || test_fail
 
 run_chronyc "selectdata" || test_fail
 check_chronyc_output "^S Name/IP Address        Auth COpts EOpts Last Score     Interval  Leap
 =======================================================================
-s 127\.0\.0\.1                 N -PTR- -PTR-    0   1\.0    \+0ns    \+0ns  \?$" || test_fail
+M 127\.0\.0\.1                 N -PTR- -PTR-    0   1\.0    \+0ns    \+0ns  \?$" || test_fail
 
 run_chronyc "serverstats" || test_fail
 check_chronyc_output "^NTP packets received       : [0-9]+

test/system/008-confload

@@ -30,6 +30,8 @@ echo "server 127.123.4.4" > $TEST_DIR/conf4.d/4.conf
 echo "server 127.123.5.1" > $TEST_DIR/conf5.d/1.sources
 echo "server 127.123.5.2" > $TEST_DIR/conf5.d/2.sources
 echo "server 127.123.5.3" > $TEST_DIR/conf5.d/3.sources
+echo "server 127.123.5.4" > $TEST_DIR/conf5.d/4.sources
+echo "server 127.123.5.5" > $TEST_DIR/conf5.d/5.sources
 
 start_chronyd || test_fail
 
@@ -46,12 +48,16 @@ check_chronyc_output "^[^=]*
 .. 127\.123\.1\.2 [^^]*
 .. 127\.123\.5\.1 [^^]*
 .. 127\.123\.5\.2 [^^]*
-.. 127\.123\.5\.3 [^^]*$" || test_fail
+.. 127\.123\.5\.3 [^^]*
+.. 127\.123\.5\.4 [^^]*
+.. 127\.123\.5\.5 [^^]*$" || test_fail
 
 rm $TEST_DIR/conf5.d/1.sources
-echo "server 127.123.5.2 minpoll 7" > $TEST_DIR/conf5.d/2.sources
+echo "server 127.123.5.2 minpoll 5" > $TEST_DIR/conf5.d/2.sources
-echo > $TEST_DIR/conf5.d/3.sources
+echo "server 127.123.5.3 minpoll 7" > $TEST_DIR/conf5.d/3.sources
-echo "server 127.123.5.4" > $TEST_DIR/conf5.d/4.sources
+echo > $TEST_DIR/conf5.d/4.sources
+echo "server 127.123.5.5" >> $TEST_DIR/conf5.d/5.sources
+echo "server 127.123.5.6" > $TEST_DIR/conf5.d/6.sources
 
 run_chronyc "reload sources" || test_fail
 
@@ -66,9 +72,37 @@ check_chronyc_output "^[^=]*
 .. 127\.123\.2\.3 [^^]*
 .. 127\.123\.4\.4 [^^]*
 .. 127\.123\.1\.2 *[05]   6 [^^]*
-.. 127\.123\.5\.2 *[05]   7 [^^]*
+.. 127\.123\.5\.5 [^^]*
-.. 127\.123\.5\.4 [^^]*$" || test_fail
+.. 127\.123\.5\.2 *[05]   5 [^^]*
+.. 127\.123\.5\.3 *[05]   7 [^^]*
+.. 127\.123\.5\.6 [^^]*$" || test_fail
+
+run_chronyc "reload sources" || test_fail
+run_chronyc "reload sources" || test_fail
+
+rm $TEST_DIR/conf5.d/{3,5,6}.sources
+echo "server 127.123.5.7" > $TEST_DIR/conf5.d/7.sources
+
+run_chronyc "reload sources" || test_fail
+
+run_chronyc "sources" || test_fail
+check_chronyc_output "^[^=]*
+=*
+.. 127\.123\.1\.1 [^^]*
+.. 127\.123\.1\.3 [^^]*
+.. 127\.123\.1\.4 [^^]*
+.. 127\.123\.3\.1 [^^]*
+.. 127\.123\.2\.2 [^^]*
+.. 127\.123\.2\.3 [^^]*
+.. 127\.123\.4\.4 [^^]*
+.. 127\.123\.1\.2 *[05]   6 [^^]*
+.. 127\.123\.5\.2 *[05]   5 [^^]*
+.. 127\.123\.5\.7 [^^]*$" || test_fail
+
+run_chronyc "reload sources" || test_fail
 
 stop_chronyd || test_fail
+check_chronyd_message_count "Could not add source.*\.5\.5.*in use" 1 1 || test_fail
+check_chronyd_message_count "Could not add source" 1 1 || test_fail
 
 test_pass

test/system/010-nts

@@ -45,6 +45,11 @@ check_chronyc_output "^Name/IP address             Mode KeyID Type KLen Last Atm
 =========================================================================
 127\.0\.0\.1                    NTS     1   (30|15)  (128|256)    [0-9]    0    0    [78]  ( 64|100)$" || test_fail
 
+run_chronyc "serverstats" || test_fail
+check_chronyc_output "NTS-KE connections accepted: 1
+NTS-KE connections dropped : 0
+Authenticated NTP packets  : [1-9][0-9]*" || test_fail
+
 stop_chronyd || test_fail
 check_chronyd_messages || test_fail
 check_chronyd_files || test_fail

test/system/011-systemd

@@ -0,0 +1,140 @@
+#!/usr/bin/env bash
+
+. ./test.common
+
+check_chronyd_features NTS || test_skip "NTS support disabled"
+certtool --help &> /dev/null || test_skip "certtool missing"
+check_chronyd_features DEBUG || test_skip "DEBUG support disabled"
+systemd-socket-activate -h &> /dev/null || test_skip "systemd-socket-activate missing"
+has_ipv6=$(check_chronyd_features IPV6 && ping6 -c 1 ::1 > /dev/null 2>&1 && echo 1 || echo 0)
+
+test_start "systemd socket activation"
+
+cat > $TEST_DIR/cert.cfg <<EOF
+cn = "chrony-nts-test"
+dns_name = "chrony-nts-test"
+ip_address = "$server"
+$([ "$has_ipv6" = "1" ] && echo 'ip_address = "::1"')
+serial = 001
+activation_date = "$[$(date '+%Y') - 1]-01-01 00:00:00 UTC"
+expiration_date = "$[$(date '+%Y') + 2]-01-01 00:00:00 UTC"
+signing_key
+encryption_key
+EOF
+
+certtool --generate-privkey --key-type=ed25519 --outfile $TEST_DIR/server.key \
+	&> $TEST_DIR/certtool.log
+certtool --generate-self-signed --load-privkey $TEST_DIR/server.key \
+	--template $TEST_DIR/cert.cfg --outfile $TEST_DIR/server.crt &>> $TEST_DIR/certtool.log
+chown $user $TEST_DIR/server.*
+
+ntpport=$(get_free_port)
+ntsport=$(get_free_port)
+
+server_options="port $ntpport nts ntsport $ntsport"
+extra_chronyd_directives="
+port $ntpport
+ntsport $ntsport
+ntsserverkey $TEST_DIR/server.key
+ntsservercert $TEST_DIR/server.crt
+ntstrustedcerts $TEST_DIR/server.crt
+ntsdumpdir $TEST_LIBDIR
+ntsprocesses 3"
+
+if [ "$has_ipv6" = "1" ]; then
+  extra_chronyd_directives="$extra_chronyd_directives
+  bindaddress ::1
+  server ::1 minpoll -6 maxpoll -6 $server_options"
+fi
+
+# enable debug logging
+extra_chronyd_options="-L -1"
+# Hack to trigger systemd-socket-activate to activate the service.  Normally,
+# chronyd.service would be configured with the WantedBy= directive so it starts
+# without waiting for socket activation.
+# (https://0pointer.de/blog/projects/socket-activation.html).
+for i in $(seq 10); do
+  sleep 1
+  (echo "wake up" > /dev/udp/127.0.0.1/$ntpport) 2>/dev/null
+  (echo "wake up" > /dev/tcp/127.0.0.1/$ntsport) 2>/dev/null
+done &
+
+# Test with UDP sockets (unfortunately systemd-socket-activate doesn't support
+# both datagram and stream sockets in the same invocation:
+# https://github.com/systemd/systemd/issues/9983).
+CHRONYD_WRAPPER="systemd-socket-activate \
+  --datagram \
+  --listen 127.0.0.1:$ntpport \
+  --listen 127.0.0.1:$ntsport"
+if [ "$has_ipv6" = "1" ]; then
+  CHRONYD_WRAPPER="$CHRONYD_WRAPPER \
+    --listen [::1]:$ntpport \
+    --listen [::1]:$ntsport"
+fi
+
+start_chronyd || test_fail
+wait_for_sync || test_fail
+
+if [ "$has_ipv6" = "1" ]; then
+  run_chronyc "ntpdata ::1" || test_fail
+  check_chronyc_output "Total RX +: [1-9]" || test_fail
+fi
+run_chronyc "authdata" || test_fail
+check_chronyc_output "^Name/IP address             Mode KeyID Type KLen Last Atmp  NAK Cook CLen
+=========================================================================\
+$([ "$has_ipv6" = "1" ] && printf "\n%s\n" '::1                          NTS     1   (30|15)  (128|256)    [0-9]    0    0    [78]  ( 64|100)')
+127\.0\.0\.1                    NTS     1   (30|15)  (128|256)    [0-9]    0    0    [78]  ( 64|100)$" || test_fail
+
+stop_chronyd || test_fail
+# DGRAM ntpport socket should be used
+check_chronyd_message_count "Reusing UDPv4 socket fd=3 local=127.0.0.1:$ntpport" 1 1 || test_fail
+# DGRAM ntsport socket should be ignored
+check_chronyd_message_count "Reusing TCPv4 socket fd=4 local=127.0.0.1:$ntsport" 0 0 || test_fail
+if [ "$has_ipv6" = "1" ]; then
+  # DGRAM ntpport socket should be used
+  check_chronyd_message_count "Reusing UDPv6 socket fd=5 local=\[::1\]:$ntpport" 1 1 || test_fail
+  # DGRAM ntsport socket should be ignored
+  check_chronyd_message_count "Reusing TCPv6 socket fd=6 local=\[::1\]:$ntsport" 0 0 || test_fail
+fi
+
+check_chronyd_messages || test_fail
+check_chronyd_files || test_fail
+
+# Test with TCP sockets
+CHRONYD_WRAPPER="systemd-socket-activate \
+  --listen 127.0.0.1:$ntpport \
+  --listen 127.0.0.1:$ntsport"
+if [ "$has_ipv6" = "1" ]; then
+  CHRONYD_WRAPPER="$CHRONYD_WRAPPER \
+    --listen [::1]:$ntpport \
+    --listen [::1]:$ntsport"
+fi
+
+start_chronyd || test_fail
+wait_for_sync || test_fail
+
+if [ "$has_ipv6" = "1" ]; then
+  run_chronyc "ntpdata ::1" || test_fail
+  check_chronyc_output "Total RX +: [1-9]" || test_fail
+fi
+run_chronyc "authdata" || test_fail
+check_chronyc_output "^Name/IP address             Mode KeyID Type KLen Last Atmp  NAK Cook CLen
+=========================================================================\
+$([ "$has_ipv6" = "1" ] && printf "\n%s\n" '::1                          NTS     1   (30|15)  (128|256)    [0-9]    0    0    [78]  ( 64|100)')
+127\.0\.0\.1                    NTS     1   (30|15)  (128|256)    [0-9]    0    0    [78]  ( 64|100)$" || test_fail
+
+stop_chronyd || test_fail
+# STREAM ntpport should be ignored
+check_chronyd_message_count "Reusing TCPv4 socket fd=3 local=127.0.0.1:$ntpport" 0 0 || test_fail
+# STREAM ntsport should be used
+check_chronyd_message_count "Reusing TCPv4 socket fd=4 local=127.0.0.1:$ntsport" 1 1 || test_fail
+if [ "$has_ipv6" = "1" ]; then
+  # STREAM ntpport should be ignored
+  check_chronyd_message_count "Reusing TCPv6 socket fd=5 local=\[::1\]:$ntpport" 0 0 || test_fail
+  # STREAM ntsport should be used
+  check_chronyd_message_count "Reusing TCPv6 socket fd=6 local=\[::1\]:$ntsport" 1 1 || test_fail
+fi
+check_chronyd_messages || test_fail
+check_chronyd_files || test_fail
+
+test_pass

test/system/test.common

@@ -324,7 +324,7 @@ check_chronyd_messages() {
 		([ "$clock_control" -ne 0 ] || grep -q 'Disabled control of system clock' "$logfile") && \
 		([ "$minimal_config" -ne 0 ] || grep -q 'Frequency .* read from' "$logfile") && \
 		grep -q 'chronyd exiting' "$logfile" && \
-		! grep -q 'Could not' "$logfile" && \
+		! (grep -v '^.\{19\}Z D:' "$logfile" | grep -q 'Could not') && \
 		! grep -q 'Disabled command socket' "$logfile" && \
 		test_ok || test_bad
 }

test/unit/clientlog.c

@@ -1,6 +1,6 @@
 /*
  **********************************************************************
- * Copyright (C) Miroslav Lichvar  2016, 2021
+ * Copyright (C) Miroslav Lichvar  2016, 2021, 2024
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -35,18 +35,18 @@ void
 test_unit(void)
 {
   uint64_t ts64, prev_first_ts64, prev_last_ts64, max_step;
+  int i, j, k, kod, passes, kods, drops, index, shift;
   uint32_t index2, prev_first, prev_size;
   NTP_Timestamp_Source ts_src, ts_src2;
   struct timespec ts, ts2;
-  int i, j, k, index, shift;
   CLG_Service s;
   NTP_int64 ntp_ts;
   IPAddr ip;
   char conf[][100] = {
     "clientloglimit 20000",
     "ratelimit interval 3 burst 4 leak 3",
-    "cmdratelimit interval 3 burst 4 leak 3",
+    "ntsratelimit interval 4 burst 8 leak 3",
-    "ntsratelimit interval 6 burst 8 leak 3",
+    "cmdratelimit interval 6 burst 4 leak 3",
   };
 
   CNF_Initialise(0, 0);
@@ -80,19 +80,51 @@ test_unit(void)
   DEBUG_LOG("records %u", ARR_GetSize(records));
   TEST_CHECK(ARR_GetSize(records) == 128);
 
-  s = CLG_NTP;
+  for (kod = 0; kod <= 2; kod += 2) {
+    for (s = CLG_NTP; s <= CLG_CMDMON; s++) {
+      for (i = passes = kods = drops = 0; i < 10000; i++) {
+        kod_rate[s] = kod;
+        ts.tv_sec += 1;
+        index = CLG_LogServiceAccess(s, &ip, &ts);
+        TEST_CHECK(index >= 0);
+        switch (CLG_LimitServiceRate(s, index)) {
+          case CLG_PASS:
+            passes += 1;
+            break;
+          case CLG_DROP:
+            drops += 1;
+            break;
+          case CLG_KOD:
+            kods += 1;
+            break;
+          default:
+            assert(0);
+        }
+      }
 
-  for (i = j = 0; i < 10000; i++) {
+      DEBUG_LOG("service %d requests %d passes %d kods %d drops %d",
-    ts.tv_sec += 1;
+                (int)s, i, passes, kods, drops);
-    index = CLG_LogServiceAccess(s, &ip, &ts);
+      if (kod)
-    TEST_CHECK(index >= 0);
+        TEST_CHECK(kods * 2.5 < drops && kods * 3.5 > drops);
-    if (!CLG_LimitServiceRate(s, index))
+      else
-      j++;
+        TEST_CHECK(kods == 0);
+
+      switch (s) {
+        case CLG_NTP:
+          TEST_CHECK(passes > 1750 && passes < 2050);
+          break;
+        case CLG_NTSKE:
+          TEST_CHECK(passes > 1300 && passes < 1600);
+          break;
+        case CLG_CMDMON:
+          TEST_CHECK(passes > 1100 && passes < 1400);
+          break;
+        default:
+          assert(0);
+      }
+    }
   }
 
-  DEBUG_LOG("requests %d responses %d", i, j);
-  TEST_CHECK(j * 4 < i && j * 6 > i);
-
   TEST_CHECK(!ntp_ts_map.timestamps);
 
   UTI_ZeroNtp64(&ntp_ts);

test/unit/leapdb.c

@@ -0,0 +1,106 @@
+/*
+ **********************************************************************
+ * Copyright (C) Patrick Oppenlander 2024
+ *
+ * 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 <leapdb.c>
+#include "test.h"
+
+struct test_vector {
+  time_t when;
+  int tai_offset;
+  NTP_Leap leap;
+  int fake;
+} tests[] = {
+  /* leapdb.list is a cut down version of leap-seconds.list */
+  {3439756800, 34, LEAP_InsertSecond, 0}, /* 1 Jan 2009 */
+  {3550089600, 35, LEAP_InsertSecond, 0}, /* 1 Jul 2012 */
+  {3644697600, 36, LEAP_InsertSecond, 0}, /* 1 Jul 2015 */
+  {3692217600, 37, LEAP_InsertSecond, 0}, /* 1 Jan 2017 */
+  {3786825600, 36, LEAP_DeleteSecond, 1}, /* 1 Jan 2020 fake in leapdb.list */
+};
+
+static void
+test_leap_source(NTP_Leap (*fn)(time_t when, int *tai_offset),
+                 int skip_fakes)
+{
+  int i, prev_tai_offset = 34;
+
+  for (i = 0; i < sizeof tests / sizeof tests[0]; ++i) {
+    struct test_vector *t = tests + i;
+
+    NTP_Leap leap;
+    int tai_offset = -1;
+
+    /* Our unit test leapdb.list contains a fake entry removing a leap second.
+     * Skip this when testing with the right/UTC timezone using mktime(). */
+    if (skip_fakes && t->fake)
+      continue;
+
+    /* One second before leap second */
+    leap = fn(t->when - LEAP_SEC_LIST_OFFSET - 1, &tai_offset);
+    TEST_CHECK(leap == t->leap);
+    TEST_CHECK(tai_offset = prev_tai_offset);
+
+    /* Exactly on leap second */
+    leap = fn(t->when - LEAP_SEC_LIST_OFFSET, &tai_offset);
+    TEST_CHECK(leap == LEAP_Normal);
+    TEST_CHECK(tai_offset == t->tai_offset);
+
+    /* One second after leap second */
+    leap = fn(t->when - LEAP_SEC_LIST_OFFSET + 1, &tai_offset);
+    TEST_CHECK(leap == LEAP_Normal);
+    TEST_CHECK(tai_offset == t->tai_offset);
+
+    prev_tai_offset = t->tai_offset;
+  }
+}
+
+void
+test_unit(void)
+{
+  char conf[][100] = {
+    "leapsectz right/UTC",
+    "leapseclist leapdb.list"
+  };
+  int i;
+
+  CNF_Initialise(0, 0);
+  for (i = 0; i < sizeof conf / sizeof conf[0]; i++)
+    CNF_ParseLine(NULL, i + 1, conf[i]);
+  LDB_Initialise();
+
+  if (check_leap_source(get_tz_leap)) {
+    DEBUG_LOG("testing get_tz_leap");
+    test_leap_source(get_tz_leap, 1);
+  } else {
+    DEBUG_LOG("Skipping get_tz_leap test. Either the right/UTC timezone is "
+	      "missing, or mktime() doesn't support leap seconds.");
+  }
+
+  DEBUG_LOG("testing get_list_leap");
+  TEST_CHECK(check_leap_source(get_list_leap));
+  test_leap_source(get_list_leap, 0);
+
+  /* This exercises the twice-per-day logic */
+  DEBUG_LOG("testing LDB_GetLeap");
+  test_leap_source(LDB_GetLeap, 1);
+
+  LDB_Finalise();
+  CNF_Finalise();
+}

test/unit/leapdb.list

@@ -0,0 +1,22 @@
+#
+# Cut down version of leap-seconds.list for unit test.
+#
+# Blank lines need to be ignored, so include a few for testing.
+# Whitespace errors on non-blank lines below are copied from the original file.
+#
+  	
+#	Leap second data update time
+#$	 3676924800
+#
+#	File update time
+#@	3928521600
+	  
+3439756800	34	# 1 Jan 2009
+3550089600	35	# 1 Jul 2012
+3644697600	36	# 1 Jul 2015
+3692217600	37	# 1 Jan 2017
+3786825600	36	# 1 Jan 2020 (fake entry to test negative leap second)
+
+#	FIPS 180-1 hash
+#	NOTE! this value has not been recomputed for this unit test file.
+#h 	16edd0f0 3666784f 37db6bdd e74ced87 59af48f1