timedated: add SNTP client/query hookup (unused for now)
This commit is contained in:
Kay Sievers
parent
42c4ebcbd4
commit
bcdbbd7ee1
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@ -186,6 +186,7 @@
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/test-strxcpyx
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/test-tables
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/test-time
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/test-timedate-sntp
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/test-tmpfiles
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/test-udev
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/test-unit-file
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27
Makefile.am
27
Makefile.am
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@ -186,6 +186,7 @@ AM_CPPFLAGS = \
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-I $(top_srcdir)/src/network \
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-I $(top_srcdir)/src/login \
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-I $(top_srcdir)/src/journal \
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-I $(top_srcdir)/src/timedate \
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-I $(top_srcdir)/src/systemd \
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-I $(top_builddir)/src/core \
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-I $(top_srcdir)/src/core \
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@ -3893,13 +3894,24 @@ EXTRA_DIST += \
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# ------------------------------------------------------------------------------
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if ENABLE_TIMEDATED
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libsystemd_timedated_core_la_SOURCES = \
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src/timedate/timedate-sntp.c \
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src/timedate/timedate-sntp.h
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libsystemd_timedated_core_la_LIBADD = \
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libsystemd-label.la \
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libsystemd-internal.la \
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libsystemd-shared.la \
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-lm
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noinst_LTLIBRARIES += \
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libsystemd-timedated-core.la
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systemd_timedated_SOURCES = \
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src/timedate/timedated.c
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systemd_timedated_LDADD = \
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libsystemd-label.la \
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libsystemd-internal.la \
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libsystemd-shared.la
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libsystemd-timedated-core.la
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rootlibexec_PROGRAMS += \
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systemd-timedated
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@ -3944,6 +3956,15 @@ dist_bashcompletion_DATA += \
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dist_zshcompletion_DATA += \
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shell-completion/zsh/_timedatectl
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test_timedate_sntp_SOURCES = \
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src/timedate/test-timedate-sntp.c
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test_timedate_sntp_LDADD = \
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libsystemd-timedated-core.la
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manual_tests += \
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test-timedate-sntp
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endif
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polkitpolicy_in_files += \
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@ -0,0 +1,107 @@
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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
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/***
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This file is part of systemd.
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Copyright 2014 Kay Sievers
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2.1 of the License, or
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(at your option) any later version.
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with systemd; If not, see <http://www.gnu.org/licenses/>.
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***/
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#include <stdlib.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <string.h>
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#include <time.h>
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#include <arpa/inet.h>
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#include <netinet/in.h>
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#include <netinet/ip.h>
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#include <sys/timex.h>
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#include <sys/socket.h>
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#include "sd-event.h"
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#include "util.h"
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#include "log.h"
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#include "timedate-sntp.h"
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typedef struct Manager Manager;
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struct Manager {
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sd_event *event;
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SNTPContext *sntp;
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};
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static void manager_free(Manager *m);
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DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_free);
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#define _cleanup_manager_free_ _cleanup_(manager_freep)
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static int manager_new(Manager **ret) {
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_cleanup_manager_free_ Manager *m = NULL;
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int r;
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m = new0(Manager, 1);
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if (!m)
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return -ENOMEM;
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r = sd_event_default(&m->event);
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if (r < 0)
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return r;
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*ret = m;
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m = NULL;
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return 0;
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}
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static void manager_free(Manager *m) {
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if (!m)
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return;
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m->sntp = sntp_unref(m->sntp);
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sd_event_unref(m->event);
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free(m);
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}
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int main(int argc, char *argv[]) {
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_cleanup_manager_free_ Manager *m = NULL;
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const char *server;
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int r;
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if (argv[1])
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log_set_max_level(LOG_DEBUG);
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r = manager_new(&m);
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if (r < 0)
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goto out;
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r = sntp_new(&m->sntp, m->event);
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if (r < 0)
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goto out;
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//server = "216.239.32.15"; /* time1.google.com */
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//server = "192.53.103.108"; /* ntp1.ptb.de */
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server = "130.102.2.123"; /* 0.au.pool.ntp.org */
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r = sntp_server_connect(m->sntp, server);
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if (r < 0)
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goto out;
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r = sd_event_loop(m->event);
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if (r < 0)
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goto out;
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out:
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return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
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}
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@ -0,0 +1,652 @@
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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
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/***
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This file is part of systemd.
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Copyright 2014 Kay Sievers
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2.1 of the License, or
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(at your option) any later version.
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with systemd; If not, see <http://www.gnu.org/licenses/>.
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***/
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/*
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* "Simple Network Time Protocol Version 4 (SNTPv4) is a subset of the
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* Network Time Protocol (NTP) used to synchronize computer clocks in
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* the Internet. SNTPv4 can be used when the ultimate performance of
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* a full NTP implementation based on RFC 1305 is neither needed nor
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* justified."
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*
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* "Unlike most NTP clients, SNTP clients normally operate with only a
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* single server at a time."
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*
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* http://tools.ietf.org/html/rfc4330
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*/
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#include <stdlib.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <string.h>
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#include <time.h>
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#include <math.h>
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#include <arpa/inet.h>
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#include <netinet/in.h>
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#include <netinet/ip.h>
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#include <sys/timex.h>
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#include <sys/socket.h>
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#include "util.h"
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#include "sparse-endian.h"
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#include "log.h"
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#include "sd-event.h"
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#include "timedate-sntp.h"
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#ifndef ADJ_SETOFFSET
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#define ADJ_SETOFFSET 0x0100 /* add 'time' to current time */
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#endif
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/* Maximum delta in seconds which the system clock is gradually adjusted
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* to approach the network time. Deltas larger that this are set by letting
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* the system time jump. The maximum for adjtime is 500ms.
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*/
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#define NTP_MAX_ADJUST 0.2
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/*
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* "Define the required accuracy of the system clock, then calculate the
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* maximum timeout. Use the longest maximum timeout possible given the system
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* constraints to minimize time server aggregate load."
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*
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* "A client MUST NOT under any conditions use a poll interval less
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* than 15 seconds."
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*/
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#define NTP_POLL_INTERVAL_MIN_SEC 16
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#define NTP_POLL_INTERVAL_MAX_SEC 2048
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#define NTP_POLL_ACCURACY_SEC 0.1
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#define NTP_LEAP_PLUSSEC 1
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#define NTP_LEAP_MINUSSEC 2
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#define NTP_LEAP_NOTINSYNC 3
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#define NTP_MODE_CLIENT 3
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#define NTP_MODE_SERVER 4
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#define NTP_FIELD_LEAP(f) (((f) >> 6) & 3)
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#define NTP_FIELD_VERSION(f) (((f) >> 3) & 7)
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#define NTP_FIELD_MODE(f) ((f) & 7)
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#define NTP_FIELD(l, v, m) (((l) << 6) | ((v) << 3) | (m))
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/*
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* "NTP timestamps are represented as a 64-bit unsigned fixed-point number,
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* in seconds relative to 0h on 1 January 1900."
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*/
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#define OFFSET_1900_1970 2208988800UL
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struct ntp_ts {
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be32_t sec;
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be32_t frac;
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} _packed_;
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struct ntp_ts_short {
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be16_t sec;
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be16_t frac;
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} _packed_;
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struct ntp_msg {
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uint8_t field;
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uint8_t stratum;
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int8_t poll;
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int8_t precision;
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struct ntp_ts_short root_delay;
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struct ntp_ts_short root_dispersion;
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char refid[4];
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struct ntp_ts reference_time;
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struct ntp_ts origin_time;
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struct ntp_ts recv_time;
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struct ntp_ts trans_time;
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} _packed_;
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struct SNTPContext {
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sd_event_source *event_receive;
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sd_event_source *event_timer;
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char *server;
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struct sockaddr_in server_addr;
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int server_socket;
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uint64_t packet_count;
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struct timespec trans_time_mon;
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struct timespec trans_time;
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bool pending;
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usec_t poll_interval;
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struct {
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double offset;
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double delay;
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} samples[8];
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unsigned int samples_idx;
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double samples_jitter;
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};
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static int sntp_arm_timer(SNTPContext *sntp);
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static int log2i(int a) {
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int exp = 0;
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assert(a > 0);
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while (a > 0) {
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a >>= 1;
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exp++;
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}
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return exp;
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}
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static double log2d(int a) {
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if (a < 0)
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return 1.0 / (1UL << - a);
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return 1UL << a;
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}
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static double ntp_ts_to_d(const struct ntp_ts *ts) {
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return be32toh(ts->sec) + ((double)be32toh(ts->frac) / UINT_MAX);
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}
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static double tv_to_d(const struct timeval *tv) {
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return tv->tv_sec + (1.0e-6 * tv->tv_usec);
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}
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static double ts_to_d(const struct timespec *ts) {
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return ts->tv_sec + (1.0e-9 * ts->tv_nsec);
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}
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static void d_to_tv(double d, struct timeval *tv) {
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tv->tv_sec = (long)d;
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tv->tv_usec = (d - tv->tv_sec) * 1000 * 1000;
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/* the kernel expects -0.3s as {-1, 7000.000} */
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if (tv->tv_usec < 0) {
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tv->tv_sec -= 1;
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tv->tv_usec += 1000 * 1000;
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}
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}
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static double square(double d) {
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return d * d;
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}
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static int sntp_send_request(SNTPContext *sntp) {
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struct ntp_msg ntpmsg = {};
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struct sockaddr_in addr = {};
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ssize_t len;
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int r;
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/*
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* "The client initializes the NTP message header, sends the request
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* to the server, and strips the time of day from the Transmit
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* Timestamp field of the reply. For this purpose, all the NTP
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* header fields are set to 0, except the Mode, VN, and optional
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* Transmit Timestamp fields."
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*/
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ntpmsg.field = NTP_FIELD(0, 4, NTP_MODE_CLIENT);
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/*
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* Set transmit timestamp, remember it; the server will send that back
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* as the origin timestamp and we have an indication that this is the
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* matching answer to our request.
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*
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* The actual value does not matter, We do not care about the correct
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* NTP UINT_MAX fraction, we just pass the plain nanosecond value.
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*/
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clock_gettime(CLOCK_MONOTONIC, &sntp->trans_time_mon);
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clock_gettime(CLOCK_REALTIME, &sntp->trans_time);
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ntpmsg.trans_time.sec = htobe32(sntp->trans_time.tv_sec + OFFSET_1900_1970);
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ntpmsg.trans_time.frac = htobe32(sntp->trans_time.tv_nsec);
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addr.sin_family = AF_INET;
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addr.sin_port = htobe16(123);
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addr.sin_addr.s_addr = inet_addr(sntp->server);
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len = sendto(sntp->server_socket, &ntpmsg, sizeof(ntpmsg), MSG_DONTWAIT, &addr, sizeof(addr));
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if (len < 0) {
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log_debug("Sending NTP request to %s failed: %m", sntp->server);
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return -errno;
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}
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sntp->pending = true;
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/* re-arm timer for next poll interval, in case the packet never arrives back */
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r = sntp_arm_timer(sntp);
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if (r < 0)
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return r;
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log_debug("Sent NTP request to: %s", sntp->server);
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return 0;
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}
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static int sntp_timer(sd_event_source *source, usec_t usec, void *userdata) {
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SNTPContext *sntp = userdata;
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assert(sntp);
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sntp_send_request(sntp);
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return 0;
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}
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|
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static int sntp_arm_timer(SNTPContext *sntp) {
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sd_event *e;
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int r;
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assert(sntp);
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assert(sntp->event_receive);
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if (sntp->poll_interval <= 0) {
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sntp->event_timer = sd_event_source_unref(sntp->event_timer);
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return 0;
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}
|
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|
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if (sntp->event_timer) {
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r = sd_event_source_set_time(sntp->event_timer, now(CLOCK_MONOTONIC) + sntp->poll_interval);
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if (r < 0)
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return r;
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return sd_event_source_set_enabled(sntp->event_timer, SD_EVENT_ONESHOT);
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}
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e = sd_event_source_get_event(sntp->event_receive);
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r = sd_event_add_monotonic(e, &sntp->event_timer, now(CLOCK_MONOTONIC) + sntp->poll_interval, 0, sntp_timer, sntp);
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if (r < 0)
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return r;
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return 0;
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}
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static int sntp_adjust_clock(SNTPContext *sntp, double offset, int leap_sec) {
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struct timex tmx = {};
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int r;
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/*
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* For small deltas, tell the kernel to gradually adjust the system
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* clock to the NTP time, larger deltas are just directly set.
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*
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* Clear STA_UNSYNC, it will enable the kernel's 11-minute mode, which
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* syncs the system time periodically to the hardware clock.
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*/
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if (offset < NTP_MAX_ADJUST && offset > -NTP_MAX_ADJUST) {
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int constant;
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constant = log2i(sntp->poll_interval / USEC_PER_SEC) - 5;
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tmx.modes |= ADJ_STATUS | ADJ_OFFSET | ADJ_TIMECONST;
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tmx.status = STA_PLL;
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tmx.offset = offset * 1000 * 1000;
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tmx.constant = constant;
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log_debug(" adjust (slew): %+f sec\n", (double)tmx.offset / USEC_PER_SEC);
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} else {
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tmx.modes = ADJ_SETOFFSET;
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d_to_tv(offset, &tmx.time);
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log_debug(" adjust (jump): %+f sec\n", tv_to_d(&tmx.time));
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}
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|
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switch (leap_sec) {
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case 1:
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tmx.status |= STA_INS;
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break;
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case -1:
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tmx.status |= STA_DEL;
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break;
|
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}
|
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|
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r = clock_adjtime(CLOCK_REALTIME, &tmx);
|
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if (r < 0)
|
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return r;
|
||||
|
||||
log_debug(" status : %04i %s\n"
|
||||
" time now : %li.%06li\n"
|
||||
" constant : %li\n"
|
||||
" offset : %+f sec\n"
|
||||
" freq offset : %+li (%+.3f ppm)\n",
|
||||
tmx.status, tmx.status & STA_UNSYNC ? "" : "sync",
|
||||
tmx.time.tv_sec, tmx.time.tv_usec,
|
||||
tmx.constant,
|
||||
(double)tmx.offset / USEC_PER_SEC,
|
||||
tmx.freq, (double)tmx.freq / 65536);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static bool sntp_sample_spike_detection(SNTPContext *sntp, double offset, double delay) {
|
||||
unsigned int i, idx_cur, idx_new, idx_min;
|
||||
double jitter;
|
||||
bool spike;
|
||||
|
||||
/* store the current data in our samples array */
|
||||
idx_cur = sntp->samples_idx;
|
||||
idx_new = (idx_cur + 1) % ELEMENTSOF(sntp->samples);
|
||||
sntp->samples_idx = idx_new;
|
||||
sntp->samples[idx_new].offset = offset;
|
||||
sntp->samples[idx_new].delay = delay;
|
||||
|
||||
sntp->packet_count++;
|
||||
|
||||
/*
|
||||
* Spike detection; compare the difference between the
|
||||
* current offset to the previous offset and jitter.
|
||||
*/
|
||||
spike = sntp->packet_count > 2 && fabs(offset - sntp->samples[idx_cur].offset) > sntp->samples_jitter * 3;
|
||||
|
||||
/* calculate new jitter value from the RMS differences relative to the lowest delay sample */
|
||||
for (idx_min = idx_cur, i = 0; i < ELEMENTSOF(sntp->samples); i++)
|
||||
if (sntp->samples[i].delay > 0 && sntp->samples[i].delay < sntp->samples[idx_min].delay)
|
||||
idx_min = i;
|
||||
|
||||
for (jitter = 0, i = 0; i < ELEMENTSOF(sntp->samples); i++)
|
||||
jitter += square(sntp->samples[i].offset - sntp->samples[idx_min].offset);
|
||||
sntp->samples_jitter = sqrt(jitter / (ELEMENTSOF(sntp->samples) - 1));
|
||||
|
||||
return spike;
|
||||
}
|
||||
|
||||
static void snmp_adjust_poll(SNTPContext *sntp, double offset, bool spike) {
|
||||
double delta;
|
||||
|
||||
if (spike) {
|
||||
if (sntp->poll_interval > NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC)
|
||||
sntp->poll_interval /= 2;
|
||||
return;
|
||||
}
|
||||
|
||||
delta = fabs(offset);
|
||||
|
||||
/* set to minimal poll interval */
|
||||
if (delta > NTP_POLL_ACCURACY_SEC) {
|
||||
sntp->poll_interval = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
|
||||
return;
|
||||
}
|
||||
|
||||
/* increase polling interval */
|
||||
if (delta < NTP_POLL_ACCURACY_SEC * 0.25) {
|
||||
if (sntp->poll_interval < NTP_POLL_INTERVAL_MAX_SEC * USEC_PER_SEC)
|
||||
sntp->poll_interval *= 2;
|
||||
return;
|
||||
}
|
||||
|
||||
/* decrease polling interval */
|
||||
if (delta > NTP_POLL_ACCURACY_SEC * 0.75) {
|
||||
if (sntp->poll_interval > NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC)
|
||||
sntp->poll_interval /= 2;
|
||||
return;
|
||||
}
|
||||
}
|
||||
|
||||
static int sntp_receive_response(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
|
||||
SNTPContext *sntp = userdata;
|
||||
unsigned char buf[sizeof(struct ntp_msg)];
|
||||
struct iovec iov = {
|
||||
.iov_base = buf,
|
||||
.iov_len = sizeof(buf),
|
||||
};
|
||||
union {
|
||||
struct cmsghdr cmsghdr;
|
||||
uint8_t buf[CMSG_SPACE(sizeof(struct timeval))];
|
||||
} control;
|
||||
struct sockaddr_in server_addr;
|
||||
struct msghdr msghdr = {
|
||||
.msg_iov = &iov,
|
||||
.msg_iovlen = 1,
|
||||
.msg_control = &control,
|
||||
.msg_controllen = sizeof(control),
|
||||
.msg_name = &server_addr,
|
||||
.msg_namelen = sizeof(server_addr),
|
||||
};
|
||||
struct cmsghdr *cmsg;
|
||||
struct timespec now;
|
||||
struct timeval *recv_time;
|
||||
ssize_t len;
|
||||
struct ntp_msg *ntpmsg;
|
||||
double origin, recv, trans, dest;
|
||||
double delay, offset;
|
||||
bool spike;
|
||||
int leap_sec;
|
||||
int r;
|
||||
|
||||
if (revents & (EPOLLHUP|EPOLLERR)) {
|
||||
log_debug("Server connection returned error, closing.");
|
||||
sntp_server_disconnect(sntp);
|
||||
return -ENOTCONN;
|
||||
}
|
||||
|
||||
len = recvmsg(fd, &msghdr, MSG_DONTWAIT);
|
||||
if (len < 0) {
|
||||
log_debug("Error receiving message, disconnecting");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (iov.iov_len < sizeof(struct ntp_msg)) {
|
||||
log_debug("Invalid response from server, disconnecting");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (sntp->server_addr.sin_addr.s_addr != server_addr.sin_addr.s_addr) {
|
||||
log_debug("Response from unknown server, disconnecting");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
recv_time = NULL;
|
||||
for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
|
||||
if (cmsg->cmsg_level != SOL_SOCKET)
|
||||
continue;
|
||||
|
||||
switch (cmsg->cmsg_type) {
|
||||
case SCM_TIMESTAMP:
|
||||
recv_time = (struct timeval *) CMSG_DATA(cmsg);
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (!recv_time) {
|
||||
log_debug("Invalid packet timestamp, disconnecting");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
ntpmsg = iov.iov_base;
|
||||
if (!sntp->pending) {
|
||||
log_debug("Unexpected reply, ignoring");
|
||||
return 0;
|
||||
}
|
||||
sntp->pending = false;
|
||||
|
||||
/* check our "time cookie" (we just stored nanoseconds in the fraction field) */
|
||||
if (be32toh(ntpmsg->origin_time.sec) != sntp->trans_time.tv_sec + OFFSET_1900_1970||
|
||||
be32toh(ntpmsg->origin_time.frac) != sntp->trans_time.tv_nsec) {
|
||||
log_debug("Invalid reply, not our transmit time, ignoring");
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (NTP_FIELD_LEAP(ntpmsg->field) == NTP_LEAP_NOTINSYNC) {
|
||||
log_debug("Server is not synchronized, disconnecting");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (NTP_FIELD_VERSION(ntpmsg->field) != 4) {
|
||||
log_debug("Response NTPv%d, disconnecting", NTP_FIELD_VERSION(ntpmsg->field));
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (NTP_FIELD_MODE(ntpmsg->field) != NTP_MODE_SERVER) {
|
||||
log_debug("Unsupported mode %d, disconnecting", NTP_FIELD_MODE(ntpmsg->field));
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* announce leap seconds */
|
||||
if (NTP_FIELD_LEAP(ntpmsg->field) & NTP_LEAP_PLUSSEC)
|
||||
leap_sec = 1;
|
||||
else if (NTP_FIELD_LEAP(ntpmsg->field) & NTP_LEAP_MINUSSEC)
|
||||
leap_sec = -1;
|
||||
else
|
||||
leap_sec = 0;
|
||||
|
||||
/*
|
||||
* "Timestamp Name ID When Generated
|
||||
* ------------------------------------------------------------
|
||||
* Originate Timestamp T1 time request sent by client
|
||||
* Receive Timestamp T2 time request received by server
|
||||
* Transmit Timestamp T3 time reply sent by server
|
||||
* Destination Timestamp T4 time reply received by client
|
||||
*
|
||||
* The roundtrip delay d and system clock offset t are defined as:
|
||||
* d = (T4 - T1) - (T3 - T2) t = ((T2 - T1) + (T3 - T4)) / 2"
|
||||
*/
|
||||
clock_gettime(CLOCK_MONOTONIC, &now);
|
||||
origin = tv_to_d(recv_time) - (ts_to_d(&now) - ts_to_d(&sntp->trans_time_mon)) + OFFSET_1900_1970;
|
||||
recv = ntp_ts_to_d(&ntpmsg->recv_time);
|
||||
trans = ntp_ts_to_d(&ntpmsg->trans_time);
|
||||
dest = tv_to_d(recv_time) + OFFSET_1900_1970;
|
||||
|
||||
offset = ((recv - origin) + (trans - dest)) / 2;
|
||||
delay = (dest - origin) - (trans - recv);
|
||||
|
||||
spike = sntp_sample_spike_detection(sntp, offset, delay);
|
||||
|
||||
snmp_adjust_poll(sntp, offset, spike);
|
||||
|
||||
log_debug("NTP response:\n"
|
||||
" leap : %u\n"
|
||||
" version : %u\n"
|
||||
" mode : %u\n"
|
||||
" stratum : %u\n"
|
||||
" precision : %f sec (%d)\n"
|
||||
" reference : %.4s\n"
|
||||
" origin : %f\n"
|
||||
" recv : %f\n"
|
||||
" transmit : %f\n"
|
||||
" dest : %f\n"
|
||||
" offset : %+f sec\n"
|
||||
" delay : %+f sec\n"
|
||||
" packet count : %llu\n"
|
||||
" jitter/spike : %f (%s)\n"
|
||||
" poll interval: %llu\n",
|
||||
NTP_FIELD_LEAP(ntpmsg->field),
|
||||
NTP_FIELD_VERSION(ntpmsg->field),
|
||||
NTP_FIELD_MODE(ntpmsg->field),
|
||||
ntpmsg->stratum,
|
||||
log2d(ntpmsg->precision), ntpmsg->precision,
|
||||
ntpmsg->stratum == 1 ? ntpmsg->refid : "n/a",
|
||||
origin - OFFSET_1900_1970,
|
||||
recv - OFFSET_1900_1970,
|
||||
trans - OFFSET_1900_1970,
|
||||
dest - OFFSET_1900_1970,
|
||||
offset, delay,
|
||||
(unsigned long long)sntp->packet_count,
|
||||
sntp->samples_jitter, spike ? "yes" : "no",
|
||||
sntp->poll_interval / USEC_PER_SEC);
|
||||
|
||||
log_info("%4llu %s %+12f", sntp->poll_interval / USEC_PER_SEC, spike ? "y" : "n", offset);
|
||||
|
||||
if (!spike) {
|
||||
r = sntp_adjust_clock(sntp, offset, leap_sec);
|
||||
if (r < 0)
|
||||
log_error("Failed to call clock_adjtime(): %m");
|
||||
}
|
||||
|
||||
r = sntp_arm_timer(sntp);
|
||||
if (r < 0)
|
||||
return r;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
int sntp_server_connect(SNTPContext *sntp, const char *server) {
|
||||
_cleanup_free_ char *s = NULL;
|
||||
|
||||
assert(sntp);
|
||||
assert(server);
|
||||
assert(sntp->server_socket >= 0);
|
||||
|
||||
s = strdup(server);
|
||||
if (!s)
|
||||
return -ENOMEM;
|
||||
|
||||
free(sntp->server);
|
||||
sntp->server = s;
|
||||
s = NULL;
|
||||
|
||||
zero(sntp->server_addr);
|
||||
sntp->server_addr.sin_family = AF_INET;
|
||||
sntp->server_addr.sin_addr.s_addr = inet_addr(server);
|
||||
|
||||
sntp->poll_interval = 2 * NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
|
||||
|
||||
return sntp_send_request(sntp);
|
||||
}
|
||||
|
||||
void sntp_server_disconnect(SNTPContext *sntp) {
|
||||
if (!sntp->server)
|
||||
return;
|
||||
|
||||
sntp->event_timer = sd_event_source_unref(sntp->event_timer);
|
||||
sntp->event_receive = sd_event_source_unref(sntp->event_receive);
|
||||
if (sntp->server_socket > 0)
|
||||
close(sntp->server_socket);
|
||||
sntp->server_socket = -1;
|
||||
zero(sntp->server_addr);
|
||||
free(sntp->server);
|
||||
sntp->server = NULL;
|
||||
}
|
||||
|
||||
int sntp_new(SNTPContext **sntp, sd_event *e) {
|
||||
_cleanup_free_ SNTPContext *c;
|
||||
_cleanup_close_ int fd = -1;
|
||||
struct sockaddr_in addr;
|
||||
const int on = 1;
|
||||
const int tos = IPTOS_LOWDELAY;
|
||||
int r;
|
||||
|
||||
c = new0(SNTPContext, 1);
|
||||
if (!c)
|
||||
return -ENOMEM;
|
||||
|
||||
fd = socket(PF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
|
||||
if (fd < 0)
|
||||
return -errno;
|
||||
|
||||
zero(addr);
|
||||
addr.sin_family = AF_INET;
|
||||
r = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
|
||||
if (r < 0)
|
||||
return -errno;
|
||||
|
||||
r = setsockopt(fd, SOL_SOCKET, SO_TIMESTAMP, &on, sizeof(on));
|
||||
if (r < 0)
|
||||
return -errno;
|
||||
|
||||
r = setsockopt(fd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos));
|
||||
if (r < 0)
|
||||
return -errno;
|
||||
|
||||
r = sd_event_add_io(e, &c->event_receive, fd, EPOLLIN, sntp_receive_response, c);
|
||||
if (r < 0)
|
||||
return r;
|
||||
|
||||
c->server_socket = fd;
|
||||
fd = -1;
|
||||
|
||||
*sntp = c;
|
||||
c = NULL;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
SNTPContext *sntp_unref(SNTPContext *sntp) {
|
||||
sntp_server_disconnect(sntp);
|
||||
free(sntp);
|
||||
return NULL;
|
||||
}
|
||||
|
|
@ -0,0 +1,33 @@
|
|||
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
|
||||
|
||||
#pragma once
|
||||
|
||||
/***
|
||||
This file is part of systemd.
|
||||
|
||||
Copyright 2014 Kay Sievers
|
||||
|
||||
systemd is free software; you can redistribute it and/or modify it
|
||||
under the terms of the GNU Lesser General Public License as published by
|
||||
the Free Software Foundation; either version 2.1 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
systemd 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
|
||||
Lesser General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU Lesser General Public License
|
||||
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
||||
***/
|
||||
|
||||
#include "util.h"
|
||||
#include "sd-event.h"
|
||||
|
||||
typedef struct SNTPContext SNTPContext;
|
||||
struct SNTPContext;
|
||||
|
||||
int sntp_new(SNTPContext **sntp, sd_event *e);
|
||||
SNTPContext *sntp_unref(SNTPContext *sntp);
|
||||
int sntp_server_connect(SNTPContext *sntp, const char *server);
|
||||
void sntp_server_disconnect(SNTPContext *sntp);
|
||||
Loading…
Reference in New Issue