1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2014 Kay Sievers, Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
29 #include <arpa/inet.h>
30 #include <netinet/in.h>
31 #include <netinet/ip.h>
32 #include <sys/timerfd.h>
33 #include <sys/timex.h>
34 #include <sys/socket.h>
36 #include <sys/prctl.h>
37 #include <sys/types.h>
42 #include "sparse-endian.h"
44 #include "socket-util.h"
46 #include "ratelimit.h"
48 #include "conf-parser.h"
49 #include "sd-daemon.h"
50 #include "event-util.h"
51 #include "network-util.h"
52 #include "clock-util.h"
53 #include "capability.h"
55 #include "timesyncd-conf.h"
56 #include "timesyncd-manager.h"
58 #define TIME_T_MAX (time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
61 #define ADJ_SETOFFSET 0x0100 /* add 'time' to current time */
64 /* expected accuracy of time synchronization; used to adjust the poll interval */
65 #define NTP_ACCURACY_SEC 0.2
68 * "A client MUST NOT under any conditions use a poll interval less
71 #define NTP_POLL_INTERVAL_MIN_SEC 32
72 #define NTP_POLL_INTERVAL_MAX_SEC 2048
75 * Maximum delta in seconds which the system clock is gradually adjusted
76 * (slew) to approach the network time. Deltas larger that this are set by
77 * letting the system time jump. The kernel's limit for adjtime is 0.5s.
79 #define NTP_MAX_ADJUST 0.4
81 /* NTP protocol, packet header */
82 #define NTP_LEAP_PLUSSEC 1
83 #define NTP_LEAP_MINUSSEC 2
84 #define NTP_LEAP_NOTINSYNC 3
85 #define NTP_MODE_CLIENT 3
86 #define NTP_MODE_SERVER 4
87 #define NTP_FIELD_LEAP(f) (((f) >> 6) & 3)
88 #define NTP_FIELD_VERSION(f) (((f) >> 3) & 7)
89 #define NTP_FIELD_MODE(f) ((f) & 7)
90 #define NTP_FIELD(l, v, m) (((l) << 6) | ((v) << 3) | (m))
93 * "NTP timestamps are represented as a 64-bit unsigned fixed-point number,
94 * in seconds relative to 0h on 1 January 1900."
96 #define OFFSET_1900_1970 2208988800UL
98 #define RETRY_USEC (30*USEC_PER_SEC)
99 #define RATELIMIT_INTERVAL_USEC (10*USEC_PER_SEC)
100 #define RATELIMIT_BURST 10
102 #define TIMEOUT_USEC (10*USEC_PER_SEC)
109 struct ntp_ts_short {
119 struct ntp_ts_short root_delay;
120 struct ntp_ts_short root_dispersion;
122 struct ntp_ts reference_time;
123 struct ntp_ts origin_time;
124 struct ntp_ts recv_time;
125 struct ntp_ts trans_time;
128 static int manager_arm_timer(Manager *m, usec_t next);
129 static int manager_clock_watch_setup(Manager *m);
131 static double ntp_ts_to_d(const struct ntp_ts *ts) {
132 return be32toh(ts->sec) + ((double)be32toh(ts->frac) / UINT_MAX);
135 static double ts_to_d(const struct timespec *ts) {
136 return ts->tv_sec + (1.0e-9 * ts->tv_nsec);
139 static double square(double d) {
143 static int manager_timeout(sd_event_source *source, usec_t usec, void *userdata) {
144 _cleanup_free_ char *pretty = NULL;
145 Manager *m = userdata;
148 assert(m->current_server_name);
149 assert(m->current_server_address);
151 server_address_pretty(m->current_server_address, &pretty);
152 log_info("Timed out waiting for reply from %s (%s).", strna(pretty), m->current_server_name->string);
154 return manager_connect(m);
157 static int manager_send_request(Manager *m) {
158 _cleanup_free_ char *pretty = NULL;
159 struct ntp_msg ntpmsg = {
161 * "The client initializes the NTP message header, sends the request
162 * to the server, and strips the time of day from the Transmit
163 * Timestamp field of the reply. For this purpose, all the NTP
164 * header fields are set to 0, except the Mode, VN, and optional
165 * Transmit Timestamp fields."
167 .field = NTP_FIELD(0, 4, NTP_MODE_CLIENT),
173 assert(m->current_server_name);
174 assert(m->current_server_address);
176 m->event_timeout = sd_event_source_unref(m->event_timeout);
179 * Set transmit timestamp, remember it; the server will send that back
180 * as the origin timestamp and we have an indication that this is the
181 * matching answer to our request.
183 * The actual value does not matter, We do not care about the correct
184 * NTP UINT_MAX fraction; we just pass the plain nanosecond value.
186 assert_se(clock_gettime(clock_boottime_or_monotonic(), &m->trans_time_mon) >= 0);
187 assert_se(clock_gettime(CLOCK_REALTIME, &m->trans_time) >= 0);
188 ntpmsg.trans_time.sec = htobe32(m->trans_time.tv_sec + OFFSET_1900_1970);
189 ntpmsg.trans_time.frac = htobe32(m->trans_time.tv_nsec);
191 server_address_pretty(m->current_server_address, &pretty);
193 len = sendto(m->server_socket, &ntpmsg, sizeof(ntpmsg), MSG_DONTWAIT, &m->current_server_address->sockaddr.sa, m->current_server_address->socklen);
194 if (len == sizeof(ntpmsg)) {
196 log_debug("Sent NTP request to %s (%s).", strna(pretty), m->current_server_name->string);
198 log_debug("Sending NTP request to %s (%s) failed: %m", strna(pretty), m->current_server_name->string);
199 return manager_connect(m);
202 /* re-arm timer with increasing timeout, in case the packets never arrive back */
203 if (m->retry_interval > 0) {
204 if (m->retry_interval < NTP_POLL_INTERVAL_MAX_SEC * USEC_PER_SEC)
205 m->retry_interval *= 2;
207 m->retry_interval = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
209 r = manager_arm_timer(m, m->retry_interval);
211 log_error("Failed to rearm timer: %s", strerror(-r));
215 r = sd_event_add_time(
218 clock_boottime_or_monotonic(),
219 now(clock_boottime_or_monotonic()) + TIMEOUT_USEC, 0,
222 log_error("Failed to arm timeout timer: %s", strerror(-r));
229 static int manager_timer(sd_event_source *source, usec_t usec, void *userdata) {
230 Manager *m = userdata;
234 return manager_send_request(m);
237 static int manager_arm_timer(Manager *m, usec_t next) {
241 assert(m->event_receive);
244 m->event_timer = sd_event_source_unref(m->event_timer);
248 if (m->event_timer) {
249 r = sd_event_source_set_time(m->event_timer, now(clock_boottime_or_monotonic()) + next);
253 return sd_event_source_set_enabled(m->event_timer, SD_EVENT_ONESHOT);
256 return sd_event_add_time(
259 clock_boottime_or_monotonic(),
260 now(clock_boottime_or_monotonic()) + next, 0,
264 static int manager_clock_watch(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
265 Manager *m = userdata;
270 manager_clock_watch_setup(m);
272 /* skip our own jumps */
279 log_info("System time changed. Resyncing.");
280 m->poll_resync = true;
282 return manager_send_request(m);
285 /* wake up when the system time changes underneath us */
286 static int manager_clock_watch_setup(Manager *m) {
288 struct itimerspec its = {
289 .it_value.tv_sec = TIME_T_MAX
296 m->event_clock_watch = sd_event_source_unref(m->event_clock_watch);
297 safe_close(m->clock_watch_fd);
299 m->clock_watch_fd = timerfd_create(CLOCK_REALTIME, TFD_NONBLOCK|TFD_CLOEXEC);
300 if (m->clock_watch_fd < 0) {
301 log_error("Failed to create timerfd: %m");
305 if (timerfd_settime(m->clock_watch_fd, TFD_TIMER_ABSTIME|TFD_TIMER_CANCEL_ON_SET, &its, NULL) < 0) {
306 log_error("Failed to set up timerfd: %m");
310 r = sd_event_add_io(m->event, &m->event_clock_watch, m->clock_watch_fd, EPOLLIN, manager_clock_watch, m);
312 log_error("Failed to create clock watch event source: %s", strerror(-r));
319 static int manager_adjust_clock(Manager *m, double offset, int leap_sec) {
320 struct timex tmx = {};
326 * For small deltas, tell the kernel to gradually adjust the system
327 * clock to the NTP time, larger deltas are just directly set.
329 if (fabs(offset) < NTP_MAX_ADJUST) {
330 tmx.modes = ADJ_STATUS | ADJ_NANO | ADJ_OFFSET | ADJ_TIMECONST | ADJ_MAXERROR | ADJ_ESTERROR;
331 tmx.status = STA_PLL;
332 tmx.offset = offset * NSEC_PER_SEC;
333 tmx.constant = log2i(m->poll_interval_usec / USEC_PER_SEC) - 4;
336 log_debug(" adjust (slew): %+.3f sec\n", offset);
338 tmx.modes = ADJ_STATUS | ADJ_NANO | ADJ_SETOFFSET;
340 /* ADJ_NANO uses nanoseconds in the microseconds field */
341 tmx.time.tv_sec = (long)offset;
342 tmx.time.tv_usec = (offset - tmx.time.tv_sec) * NSEC_PER_SEC;
344 /* the kernel expects -0.3s as {-1, 7000.000.000} */
345 if (tmx.time.tv_usec < 0) {
346 tmx.time.tv_sec -= 1;
347 tmx.time.tv_usec += NSEC_PER_SEC;
351 log_debug(" adjust (jump): %+.3f sec\n", offset);
355 * An unset STA_UNSYNC will enable the kernel's 11-minute mode,
356 * which syncs the system time periodically to the RTC.
358 * In case the RTC runs in local time, never touch the RTC,
359 * we have no way to properly handle daylight saving changes and
360 * mobile devices moving between time zones.
362 if (m->rtc_local_time)
363 tmx.status |= STA_UNSYNC;
367 tmx.status |= STA_INS;
370 tmx.status |= STA_DEL;
374 r = clock_adjtime(CLOCK_REALTIME, &tmx);
378 touch("/var/lib/systemd/clock");
380 m->drift_ppm = tmx.freq / 65536;
382 log_debug(" status : %04i %s\n"
383 " time now : %li.%03llu\n"
385 " offset : %+.3f sec\n"
386 " freq offset : %+li (%i ppm)\n",
387 tmx.status, tmx.status & STA_UNSYNC ? "unsync" : "sync",
388 tmx.time.tv_sec, (unsigned long long) (tmx.time.tv_usec / NSEC_PER_MSEC),
390 (double)tmx.offset / NSEC_PER_SEC,
391 tmx.freq, m->drift_ppm);
396 static bool manager_sample_spike_detection(Manager *m, double offset, double delay) {
397 unsigned int i, idx_cur, idx_new, idx_min;
405 /* ignore initial sample */
406 if (m->packet_count == 1)
409 /* store the current data in our samples array */
410 idx_cur = m->samples_idx;
411 idx_new = (idx_cur + 1) % ELEMENTSOF(m->samples);
412 m->samples_idx = idx_new;
413 m->samples[idx_new].offset = offset;
414 m->samples[idx_new].delay = delay;
416 /* calculate new jitter value from the RMS differences relative to the lowest delay sample */
417 jitter = m->samples_jitter;
418 for (idx_min = idx_cur, i = 0; i < ELEMENTSOF(m->samples); i++)
419 if (m->samples[i].delay > 0 && m->samples[i].delay < m->samples[idx_min].delay)
423 for (i = 0; i < ELEMENTSOF(m->samples); i++)
424 j += square(m->samples[i].offset - m->samples[idx_min].offset);
425 m->samples_jitter = sqrt(j / (ELEMENTSOF(m->samples) - 1));
427 /* ignore samples when resyncing */
431 /* always accept offset if we are farther off than the round-trip delay */
432 if (fabs(offset) > delay)
435 /* we need a few samples before looking at them */
436 if (m->packet_count < 4)
439 /* do not accept anything worse than the maximum possible error of the best sample */
440 if (fabs(offset) > m->samples[idx_min].delay)
443 /* compare the difference between the current offset to the previous offset and jitter */
444 return fabs(offset - m->samples[idx_cur].offset) > 3 * jitter;
447 static void manager_adjust_poll(Manager *m, double offset, bool spike) {
450 if (m->poll_resync) {
451 m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
452 m->poll_resync = false;
456 /* set to minimal poll interval */
457 if (!spike && fabs(offset) > NTP_ACCURACY_SEC) {
458 m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
462 /* increase polling interval */
463 if (fabs(offset) < NTP_ACCURACY_SEC * 0.25) {
464 if (m->poll_interval_usec < NTP_POLL_INTERVAL_MAX_SEC * USEC_PER_SEC)
465 m->poll_interval_usec *= 2;
469 /* decrease polling interval */
470 if (spike || fabs(offset) > NTP_ACCURACY_SEC * 0.75) {
471 if (m->poll_interval_usec > NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC)
472 m->poll_interval_usec /= 2;
477 static int manager_receive_response(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
478 Manager *m = userdata;
479 struct ntp_msg ntpmsg;
483 .iov_len = sizeof(ntpmsg),
486 struct cmsghdr cmsghdr;
487 uint8_t buf[CMSG_SPACE(sizeof(struct timeval))];
489 union sockaddr_union server_addr;
490 struct msghdr msghdr = {
493 .msg_control = &control,
494 .msg_controllen = sizeof(control),
495 .msg_name = &server_addr,
496 .msg_namelen = sizeof(server_addr),
498 struct cmsghdr *cmsg;
499 struct timespec *recv_time;
501 double origin, receive, trans, dest;
502 double delay, offset;
510 if (revents & (EPOLLHUP|EPOLLERR)) {
511 log_warning("Server connection returned error.");
512 return manager_connect(m);
515 len = recvmsg(fd, &msghdr, MSG_DONTWAIT);
520 log_warning("Error receiving message. Disconnecting.");
521 return manager_connect(m);
524 if (iov.iov_len < sizeof(struct ntp_msg)) {
525 log_warning("Invalid response from server. Disconnecting.");
526 return manager_connect(m);
529 if (!m->current_server_name ||
530 !m->current_server_address ||
531 !sockaddr_equal(&server_addr, &m->current_server_address->sockaddr)) {
532 log_debug("Response from unknown server.");
537 for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
538 if (cmsg->cmsg_level != SOL_SOCKET)
541 switch (cmsg->cmsg_type) {
542 case SCM_TIMESTAMPNS:
543 recv_time = (struct timespec *) CMSG_DATA(cmsg);
548 log_error("Invalid packet timestamp.");
553 log_debug("Unexpected reply. Ignoring.");
557 /* check our "time cookie" (we just stored nanoseconds in the fraction field) */
558 if (be32toh(ntpmsg.origin_time.sec) != m->trans_time.tv_sec + OFFSET_1900_1970 ||
559 be32toh(ntpmsg.origin_time.frac) != m->trans_time.tv_nsec) {
560 log_debug("Invalid reply; not our transmit time. Ignoring.");
564 m->event_timeout = sd_event_source_unref(m->event_timeout);
566 if (be32toh(ntpmsg.recv_time.sec) < TIME_EPOCH + OFFSET_1900_1970 ||
567 be32toh(ntpmsg.trans_time.sec) < TIME_EPOCH + OFFSET_1900_1970) {
568 log_debug("Invalid reply, returned times before epoch. Ignoring.");
569 return manager_connect(m);
572 if (NTP_FIELD_LEAP(ntpmsg.field) == NTP_LEAP_NOTINSYNC ||
573 ntpmsg.stratum == 0 || ntpmsg.stratum >= 16) {
574 log_debug("Server is not synchronized. Disconnecting.");
575 return manager_connect(m);
578 if (!IN_SET(NTP_FIELD_VERSION(ntpmsg.field), 3, 4)) {
579 log_debug("Response NTPv%d. Disconnecting.", NTP_FIELD_VERSION(ntpmsg.field));
580 return manager_connect(m);
583 if (NTP_FIELD_MODE(ntpmsg.field) != NTP_MODE_SERVER) {
584 log_debug("Unsupported mode %d. Disconnecting.", NTP_FIELD_MODE(ntpmsg.field));
585 return manager_connect(m);
590 m->retry_interval = 0;
592 /* announce leap seconds */
593 if (NTP_FIELD_LEAP(ntpmsg.field) & NTP_LEAP_PLUSSEC)
595 else if (NTP_FIELD_LEAP(ntpmsg.field) & NTP_LEAP_MINUSSEC)
601 * "Timestamp Name ID When Generated
602 * ------------------------------------------------------------
603 * Originate Timestamp T1 time request sent by client
604 * Receive Timestamp T2 time request received by server
605 * Transmit Timestamp T3 time reply sent by server
606 * Destination Timestamp T4 time reply received by client
608 * The round-trip delay, d, and system clock offset, t, are defined as:
609 * d = (T4 - T1) - (T3 - T2) t = ((T2 - T1) + (T3 - T4)) / 2"
611 origin = ts_to_d(&m->trans_time) + OFFSET_1900_1970;
612 receive = ntp_ts_to_d(&ntpmsg.recv_time);
613 trans = ntp_ts_to_d(&ntpmsg.trans_time);
614 dest = ts_to_d(recv_time) + OFFSET_1900_1970;
616 offset = ((receive - origin) + (trans - dest)) / 2;
617 delay = (dest - origin) - (trans - receive);
619 spike = manager_sample_spike_detection(m, offset, delay);
621 manager_adjust_poll(m, offset, spike);
623 log_debug("NTP response:\n"
628 " precision : %.6f sec (%d)\n"
629 " reference : %.4s\n"
634 " offset : %+.3f sec\n"
635 " delay : %+.3f sec\n"
636 " packet count : %"PRIu64"\n"
638 " poll interval: " USEC_FMT "\n",
639 NTP_FIELD_LEAP(ntpmsg.field),
640 NTP_FIELD_VERSION(ntpmsg.field),
641 NTP_FIELD_MODE(ntpmsg.field),
643 exp2(ntpmsg.precision), ntpmsg.precision,
644 ntpmsg.stratum == 1 ? ntpmsg.refid : "n/a",
645 origin - OFFSET_1900_1970,
646 receive - OFFSET_1900_1970,
647 trans - OFFSET_1900_1970,
648 dest - OFFSET_1900_1970,
651 m->samples_jitter, spike ? " spike" : "",
652 m->poll_interval_usec / USEC_PER_SEC);
656 r = manager_adjust_clock(m, offset, leap_sec);
658 log_error("Failed to call clock_adjtime(): %m");
661 log_info("interval/delta/delay/jitter/drift " USEC_FMT "s/%+.3fs/%.3fs/%.3fs/%+ippm%s",
662 m->poll_interval_usec / USEC_PER_SEC, offset, delay, m->samples_jitter, m->drift_ppm,
663 spike ? " (ignored)" : "");
665 r = manager_arm_timer(m, m->poll_interval_usec);
667 log_error("Failed to rearm timer: %s", strerror(-r));
674 static int manager_listen_setup(Manager *m) {
675 union sockaddr_union addr = {};
676 static const int tos = IPTOS_LOWDELAY;
677 static const int on = 1;
682 assert(m->server_socket < 0);
683 assert(!m->event_receive);
684 assert(m->current_server_address);
686 addr.sa.sa_family = m->current_server_address->sockaddr.sa.sa_family;
688 m->server_socket = socket(addr.sa.sa_family, SOCK_DGRAM | SOCK_CLOEXEC, 0);
689 if (m->server_socket < 0)
692 r = bind(m->server_socket, &addr.sa, m->current_server_address->socklen);
696 r = setsockopt(m->server_socket, SOL_SOCKET, SO_TIMESTAMPNS, &on, sizeof(on));
700 setsockopt(m->server_socket, IPPROTO_IP, IP_TOS, &tos, sizeof(tos));
702 return sd_event_add_io(m->event, &m->event_receive, m->server_socket, EPOLLIN, manager_receive_response, m);
705 static int manager_begin(Manager *m) {
706 _cleanup_free_ char *pretty = NULL;
710 assert_return(m->current_server_name, -EHOSTUNREACH);
711 assert_return(m->current_server_address, -EHOSTUNREACH);
713 m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
715 server_address_pretty(m->current_server_address, &pretty);
716 log_info("Using NTP server %s (%s).", strna(pretty), m->current_server_name->string);
717 sd_notifyf(false, "STATUS=Using Time Server %s (%s).", strna(pretty), m->current_server_name->string);
719 r = manager_listen_setup(m);
721 log_warning("Failed to setup connection socket: %s", strerror(-r));
725 r = manager_clock_watch_setup(m);
729 return manager_send_request(m);
732 void manager_set_server_name(Manager *m, ServerName *n) {
735 if (m->current_server_name == n)
738 m->current_server_name = n;
739 m->current_server_address = NULL;
741 manager_disconnect(m);
744 log_debug("Selected server %s.", n->string);
747 void manager_set_server_address(Manager *m, ServerAddress *a) {
750 if (m->current_server_address == a)
753 m->current_server_name = a ? a->name : NULL;
754 m->current_server_address = a;
756 manager_disconnect(m);
759 _cleanup_free_ char *pretty = NULL;
760 server_address_pretty(a, &pretty);
761 log_debug("Selected address %s of server %s.", strna(pretty), a->name->string);
765 static int manager_resolve_handler(sd_resolve_query *q, int ret, const struct addrinfo *ai, void *userdata) {
766 Manager *m = userdata;
771 assert(m->current_server_name);
773 m->resolve_query = sd_resolve_query_unref(m->resolve_query);
776 log_debug("Failed to resolve %s: %s", m->current_server_name->string, gai_strerror(ret));
779 return manager_connect(m);
782 for (; ai; ai = ai->ai_next) {
783 _cleanup_free_ char *pretty = NULL;
787 assert(ai->ai_addrlen >= offsetof(struct sockaddr, sa_data));
789 if (!IN_SET(ai->ai_addr->sa_family, AF_INET, AF_INET6)) {
790 log_warning("Unsuitable address protocol for %s", m->current_server_name->string);
794 r = server_address_new(m->current_server_name, &a, (const union sockaddr_union*) ai->ai_addr, ai->ai_addrlen);
796 log_error("Failed to add server address: %s", strerror(-r));
800 server_address_pretty(a, &pretty);
801 log_debug("Resolved address %s for %s.", pretty, m->current_server_name->string);
804 if (!m->current_server_name->addresses) {
805 log_error("Failed to find suitable address for host %s.", m->current_server_name->string);
808 return manager_connect(m);
811 manager_set_server_address(m, m->current_server_name->addresses);
813 return manager_begin(m);
816 static int manager_retry_connect(sd_event_source *source, usec_t usec, void *userdata) {
817 Manager *m = userdata;
821 return manager_connect(m);
824 int manager_connect(Manager *m) {
829 manager_disconnect(m);
831 m->event_retry = sd_event_source_unref(m->event_retry);
832 if (!ratelimit_test(&m->ratelimit)) {
833 log_debug("Slowing down attempts to contact servers.");
835 r = sd_event_add_time(m->event, &m->event_retry, clock_boottime_or_monotonic(), now(clock_boottime_or_monotonic()) + RETRY_USEC, 0, manager_retry_connect, m);
837 log_error("Failed to create retry timer: %s", strerror(-r));
844 /* If we already are operating on some address, switch to the
846 if (m->current_server_address && m->current_server_address->addresses_next)
847 manager_set_server_address(m, m->current_server_address->addresses_next);
849 struct addrinfo hints = {
850 .ai_flags = AI_NUMERICSERV|AI_ADDRCONFIG,
851 .ai_socktype = SOCK_DGRAM,
854 /* Hmm, we are through all addresses, let's look for the next host instead */
855 if (m->current_server_name && m->current_server_name->names_next)
856 manager_set_server_name(m, m->current_server_name->names_next);
860 /* Our current server name list is exhausted,
861 * let's find the next one to iterate. First
862 * we try the system list, then the link list.
863 * After having processed the link list we
864 * jump back to the system list. However, if
865 * both lists are empty, we change to the
867 if (!m->current_server_name || m->current_server_name->type == SERVER_LINK) {
868 f = m->system_servers;
874 f = m->system_servers;
878 f = m->fallback_servers;
881 manager_set_server_name(m, NULL);
882 log_debug("No server found.");
886 manager_set_server_name(m, f);
889 /* Tell the resolver to reread /etc/resolv.conf, in
890 * case it changed. */
893 /* Flush out any previously resolved addresses */
894 server_name_flush_addresses(m->current_server_name);
896 log_debug("Resolving %s...", m->current_server_name->string);
898 r = sd_resolve_getaddrinfo(m->resolve, &m->resolve_query, m->current_server_name->string, "123", &hints, manager_resolve_handler, m);
900 log_error("Failed to create resolver: %s", strerror(-r));
907 r = manager_begin(m);
914 void manager_disconnect(Manager *m) {
917 m->resolve_query = sd_resolve_query_unref(m->resolve_query);
919 m->event_timer = sd_event_source_unref(m->event_timer);
921 m->event_receive = sd_event_source_unref(m->event_receive);
922 m->server_socket = safe_close(m->server_socket);
924 m->event_clock_watch = sd_event_source_unref(m->event_clock_watch);
925 m->clock_watch_fd = safe_close(m->clock_watch_fd);
927 m->event_timeout = sd_event_source_unref(m->event_timeout);
929 sd_notifyf(false, "STATUS=Idle.");
932 void manager_flush_server_names(Manager *m, ServerType t) {
935 if (t == SERVER_SYSTEM)
936 while (m->system_servers)
937 server_name_free(m->system_servers);
939 if (t == SERVER_LINK)
940 while (m->link_servers)
941 server_name_free(m->link_servers);
943 if (t == SERVER_FALLBACK)
944 while (m->fallback_servers)
945 server_name_free(m->fallback_servers);
948 void manager_free(Manager *m) {
952 manager_disconnect(m);
953 manager_flush_server_names(m, SERVER_SYSTEM);
954 manager_flush_server_names(m, SERVER_LINK);
955 manager_flush_server_names(m, SERVER_FALLBACK);
957 sd_event_source_unref(m->event_retry);
959 sd_event_source_unref(m->network_event_source);
960 sd_network_monitor_unref(m->network_monitor);
962 sd_resolve_unref(m->resolve);
963 sd_event_unref(m->event);
968 static int manager_network_read_link_servers(Manager *m) {
969 _cleanup_strv_free_ char **ntp = NULL;
976 r = sd_network_get_ntp(&ntp);
980 LIST_FOREACH(names, n, m->link_servers)
983 STRV_FOREACH(i, ntp) {
986 LIST_FOREACH(names, n, m->link_servers)
987 if (streq(n->string, *i)) {
994 r = server_name_new(m, NULL, SERVER_LINK, *i);
1000 LIST_FOREACH_SAFE(names, n, nx, m->link_servers)
1002 server_name_free(n);
1007 manager_flush_server_names(m, SERVER_LINK);
1011 static int manager_network_event_handler(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
1012 Manager *m = userdata;
1013 bool connected, online;
1018 sd_network_monitor_flush(m->network_monitor);
1020 manager_network_read_link_servers(m);
1022 /* check if the machine is online */
1023 online = network_is_online();
1025 /* check if the client is currently connected */
1026 connected = m->server_socket >= 0 || m->resolve_query;
1028 if (connected && !online) {
1029 log_info("No network connectivity, watching for changes.");
1030 manager_disconnect(m);
1032 } else if (!connected && online) {
1033 log_info("Network configuration changed, trying to establish connection.");
1035 if (m->current_server_address)
1036 r = manager_begin(m);
1038 r = manager_connect(m);
1046 static int manager_network_monitor_listen(Manager *m) {
1051 r = sd_network_monitor_new(&m->network_monitor, NULL);
1055 fd = sd_network_monitor_get_fd(m->network_monitor);
1059 events = sd_network_monitor_get_events(m->network_monitor);
1063 r = sd_event_add_io(m->event, &m->network_event_source, fd, events, manager_network_event_handler, m);
1070 int manager_new(Manager **ret) {
1071 _cleanup_(manager_freep) Manager *m = NULL;
1076 m = new0(Manager, 1);
1080 m->server_socket = m->clock_watch_fd = -1;
1082 RATELIMIT_INIT(m->ratelimit, RATELIMIT_INTERVAL_USEC, RATELIMIT_BURST);
1084 r = manager_parse_server_string(m, SERVER_FALLBACK, NTP_SERVERS);
1088 r = sd_event_default(&m->event);
1092 sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
1093 sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
1095 sd_event_set_watchdog(m->event, true);
1097 r = sd_resolve_default(&m->resolve);
1101 r = sd_resolve_attach_event(m->resolve, m->event, 0);
1105 r = manager_network_monitor_listen(m);
1109 manager_network_read_link_servers(m);