1 /* SPDX-License-Identifier: LGPL-2.1+ */
3 This file is part of systemd.
5 Copyright 2014 Kay Sievers, Lennart Poettering
10 #include <netinet/in.h>
11 #include <netinet/ip.h>
14 #include <sys/socket.h>
15 #include <sys/timerfd.h>
16 #include <sys/timex.h>
17 #include <sys/types.h>
20 #include "sd-daemon.h"
22 #include "alloc-util.h"
28 #include "network-util.h"
29 #include "ratelimit.h"
30 #include "socket-util.h"
31 #include "sparse-endian.h"
32 #include "string-util.h"
34 #include "time-util.h"
35 #include "timesyncd-conf.h"
36 #include "timesyncd-manager.h"
40 #define ADJ_SETOFFSET 0x0100 /* add 'time' to current time */
43 /* expected accuracy of time synchronization; used to adjust the poll interval */
44 #define NTP_ACCURACY_SEC 0.2
47 * Maximum delta in seconds which the system clock is gradually adjusted
48 * (slewed) to approach the network time. Deltas larger that this are set by
49 * letting the system time jump. The kernel's limit for adjtime is 0.5s.
51 #define NTP_MAX_ADJUST 0.4
53 /* NTP protocol, packet header */
54 #define NTP_LEAP_PLUSSEC 1
55 #define NTP_LEAP_MINUSSEC 2
56 #define NTP_LEAP_NOTINSYNC 3
57 #define NTP_MODE_CLIENT 3
58 #define NTP_MODE_SERVER 4
59 #define NTP_FIELD_LEAP(f) (((f) >> 6) & 3)
60 #define NTP_FIELD_VERSION(f) (((f) >> 3) & 7)
61 #define NTP_FIELD_MODE(f) ((f) & 7)
62 #define NTP_FIELD(l, v, m) (((l) << 6) | ((v) << 3) | (m))
64 /* Default of maximum acceptable root distance in microseconds. */
65 #define NTP_MAX_ROOT_DISTANCE (5 * USEC_PER_SEC)
67 /* Maximum number of missed replies before selecting another source. */
68 #define NTP_MAX_MISSED_REPLIES 2
71 * "NTP timestamps are represented as a 64-bit unsigned fixed-point number,
72 * in seconds relative to 0h on 1 January 1900."
74 #define OFFSET_1900_1970 UINT64_C(2208988800)
76 #define RETRY_USEC (30*USEC_PER_SEC)
77 #define RATELIMIT_INTERVAL_USEC (10*USEC_PER_SEC)
78 #define RATELIMIT_BURST 10
80 #define TIMEOUT_USEC (10*USEC_PER_SEC)
97 struct ntp_ts_short root_delay
;
98 struct ntp_ts_short root_dispersion
;
100 struct ntp_ts reference_time
;
101 struct ntp_ts origin_time
;
102 struct ntp_ts recv_time
;
103 struct ntp_ts trans_time
;
106 static int manager_arm_timer(Manager
*m
, usec_t next
);
107 static int manager_clock_watch_setup(Manager
*m
);
108 static int manager_listen_setup(Manager
*m
);
109 static void manager_listen_stop(Manager
*m
);
111 static double ntp_ts_short_to_d(const struct ntp_ts_short
*ts
) {
112 return be16toh(ts
->sec
) + (be16toh(ts
->frac
) / 65536.0);
115 static double ntp_ts_to_d(const struct ntp_ts
*ts
) {
116 return be32toh(ts
->sec
) + ((double)be32toh(ts
->frac
) / UINT_MAX
);
119 static double ts_to_d(const struct timespec
*ts
) {
120 return ts
->tv_sec
+ (1.0e-9 * ts
->tv_nsec
);
123 static int manager_timeout(sd_event_source
*source
, usec_t usec
, void *userdata
) {
124 _cleanup_free_
char *pretty
= NULL
;
125 Manager
*m
= userdata
;
128 assert(m
->current_server_name
);
129 assert(m
->current_server_address
);
131 server_address_pretty(m
->current_server_address
, &pretty
);
132 log_info("Timed out waiting for reply from %s (%s).", strna(pretty
), m
->current_server_name
->string
);
134 return manager_connect(m
);
137 static int manager_send_request(Manager
*m
) {
138 _cleanup_free_
char *pretty
= NULL
;
139 struct ntp_msg ntpmsg
= {
141 * "The client initializes the NTP message header, sends the request
142 * to the server, and strips the time of day from the Transmit
143 * Timestamp field of the reply. For this purpose, all the NTP
144 * header fields are set to 0, except the Mode, VN, and optional
145 * Transmit Timestamp fields."
147 .field
= NTP_FIELD(0, 4, NTP_MODE_CLIENT
),
153 assert(m
->current_server_name
);
154 assert(m
->current_server_address
);
156 m
->event_timeout
= sd_event_source_unref(m
->event_timeout
);
158 r
= manager_listen_setup(m
);
160 return log_warning_errno(r
, "Failed to setup connection socket: %m");
163 * Set transmit timestamp, remember it; the server will send that back
164 * as the origin timestamp and we have an indication that this is the
165 * matching answer to our request.
167 * The actual value does not matter, We do not care about the correct
168 * NTP UINT_MAX fraction; we just pass the plain nanosecond value.
170 assert_se(clock_gettime(clock_boottime_or_monotonic(), &m
->trans_time_mon
) >= 0);
171 assert_se(clock_gettime(CLOCK_REALTIME
, &m
->trans_time
) >= 0);
172 ntpmsg
.trans_time
.sec
= htobe32(m
->trans_time
.tv_sec
+ OFFSET_1900_1970
);
173 ntpmsg
.trans_time
.frac
= htobe32(m
->trans_time
.tv_nsec
);
175 server_address_pretty(m
->current_server_address
, &pretty
);
177 len
= sendto(m
->server_socket
, &ntpmsg
, sizeof(ntpmsg
), MSG_DONTWAIT
, &m
->current_server_address
->sockaddr
.sa
, m
->current_server_address
->socklen
);
178 if (len
== sizeof(ntpmsg
)) {
180 log_debug("Sent NTP request to %s (%s).", strna(pretty
), m
->current_server_name
->string
);
182 log_debug_errno(errno
, "Sending NTP request to %s (%s) failed: %m", strna(pretty
), m
->current_server_name
->string
);
183 return manager_connect(m
);
186 /* re-arm timer with increasing timeout, in case the packets never arrive back */
187 if (m
->retry_interval
> 0) {
188 if (m
->retry_interval
< m
->poll_interval_max_usec
)
189 m
->retry_interval
*= 2;
191 m
->retry_interval
= m
->poll_interval_min_usec
;
193 r
= manager_arm_timer(m
, m
->retry_interval
);
195 return log_error_errno(r
, "Failed to rearm timer: %m");
198 if (m
->missed_replies
> NTP_MAX_MISSED_REPLIES
) {
199 r
= sd_event_add_time(
202 clock_boottime_or_monotonic(),
203 now(clock_boottime_or_monotonic()) + TIMEOUT_USEC
, 0,
206 return log_error_errno(r
, "Failed to arm timeout timer: %m");
212 static int manager_timer(sd_event_source
*source
, usec_t usec
, void *userdata
) {
213 Manager
*m
= userdata
;
217 return manager_send_request(m
);
220 static int manager_arm_timer(Manager
*m
, usec_t next
) {
226 m
->event_timer
= sd_event_source_unref(m
->event_timer
);
230 if (m
->event_timer
) {
231 r
= sd_event_source_set_time(m
->event_timer
, now(clock_boottime_or_monotonic()) + next
);
235 return sd_event_source_set_enabled(m
->event_timer
, SD_EVENT_ONESHOT
);
238 return sd_event_add_time(
241 clock_boottime_or_monotonic(),
242 now(clock_boottime_or_monotonic()) + next
, 0,
246 static int manager_clock_watch(sd_event_source
*source
, int fd
, uint32_t revents
, void *userdata
) {
247 Manager
*m
= userdata
;
252 manager_clock_watch_setup(m
);
254 /* skip our own jumps */
261 log_debug("System time changed. Resyncing.");
262 m
->poll_resync
= true;
264 return manager_send_request(m
);
267 /* wake up when the system time changes underneath us */
268 static int manager_clock_watch_setup(Manager
*m
) {
270 struct itimerspec its
= {
271 .it_value
.tv_sec
= TIME_T_MAX
278 m
->event_clock_watch
= sd_event_source_unref(m
->event_clock_watch
);
279 safe_close(m
->clock_watch_fd
);
281 m
->clock_watch_fd
= timerfd_create(CLOCK_REALTIME
, TFD_NONBLOCK
|TFD_CLOEXEC
);
282 if (m
->clock_watch_fd
< 0)
283 return log_error_errno(errno
, "Failed to create timerfd: %m");
285 if (timerfd_settime(m
->clock_watch_fd
, TFD_TIMER_ABSTIME
|TFD_TIMER_CANCEL_ON_SET
, &its
, NULL
) < 0)
286 return log_error_errno(errno
, "Failed to set up timerfd: %m");
288 r
= sd_event_add_io(m
->event
, &m
->event_clock_watch
, m
->clock_watch_fd
, EPOLLIN
, manager_clock_watch
, m
);
290 return log_error_errno(r
, "Failed to create clock watch event source: %m");
295 static int manager_adjust_clock(Manager
*m
, double offset
, int leap_sec
) {
296 struct timex tmx
= {};
302 * For small deltas, tell the kernel to gradually adjust the system
303 * clock to the NTP time, larger deltas are just directly set.
305 if (fabs(offset
) < NTP_MAX_ADJUST
) {
306 tmx
.modes
= ADJ_STATUS
| ADJ_NANO
| ADJ_OFFSET
| ADJ_TIMECONST
| ADJ_MAXERROR
| ADJ_ESTERROR
;
307 tmx
.status
= STA_PLL
;
308 tmx
.offset
= offset
* NSEC_PER_SEC
;
309 tmx
.constant
= log2i(m
->poll_interval_usec
/ USEC_PER_SEC
) - 4;
312 log_debug(" adjust (slew): %+.3f sec", offset
);
314 tmx
.modes
= ADJ_STATUS
| ADJ_NANO
| ADJ_SETOFFSET
| ADJ_MAXERROR
| ADJ_ESTERROR
;
316 /* ADJ_NANO uses nanoseconds in the microseconds field */
317 tmx
.time
.tv_sec
= (long)offset
;
318 tmx
.time
.tv_usec
= (offset
- tmx
.time
.tv_sec
) * NSEC_PER_SEC
;
322 /* the kernel expects -0.3s as {-1, 7000.000.000} */
323 if (tmx
.time
.tv_usec
< 0) {
324 tmx
.time
.tv_sec
-= 1;
325 tmx
.time
.tv_usec
+= NSEC_PER_SEC
;
329 log_debug(" adjust (jump): %+.3f sec", offset
);
333 * An unset STA_UNSYNC will enable the kernel's 11-minute mode,
334 * which syncs the system time periodically to the RTC.
336 * In case the RTC runs in local time, never touch the RTC,
337 * we have no way to properly handle daylight saving changes and
338 * mobile devices moving between time zones.
340 if (m
->rtc_local_time
)
341 tmx
.status
|= STA_UNSYNC
;
345 tmx
.status
|= STA_INS
;
348 tmx
.status
|= STA_DEL
;
352 r
= clock_adjtime(CLOCK_REALTIME
, &tmx
);
356 /* If touch fails, there isn't much we can do. Maybe it'll work next time. */
357 (void) touch("/var/lib/systemd/timesync/clock");
358 (void) touch("/run/systemd/timesync/synchronized");
360 m
->drift_ppm
= tmx
.freq
/ 65536;
362 log_debug(" status : %04i %s\n"
363 " time now : %"PRI_TIME
".%03"PRI_USEC
"\n"
364 " constant : %"PRI_TIMEX
"\n"
365 " offset : %+.3f sec\n"
366 " freq offset : %+"PRI_TIMEX
" (%i ppm)\n",
367 tmx
.status
, tmx
.status
& STA_UNSYNC
? "unsync" : "sync",
368 tmx
.time
.tv_sec
, tmx
.time
.tv_usec
/ NSEC_PER_MSEC
,
370 (double)tmx
.offset
/ NSEC_PER_SEC
,
371 tmx
.freq
, m
->drift_ppm
);
376 static bool manager_sample_spike_detection(Manager
*m
, double offset
, double delay
) {
377 unsigned int i
, idx_cur
, idx_new
, idx_min
;
385 /* ignore initial sample */
386 if (m
->packet_count
== 1)
389 /* store the current data in our samples array */
390 idx_cur
= m
->samples_idx
;
391 idx_new
= (idx_cur
+ 1) % ELEMENTSOF(m
->samples
);
392 m
->samples_idx
= idx_new
;
393 m
->samples
[idx_new
].offset
= offset
;
394 m
->samples
[idx_new
].delay
= delay
;
396 /* calculate new jitter value from the RMS differences relative to the lowest delay sample */
397 jitter
= m
->samples_jitter
;
398 for (idx_min
= idx_cur
, i
= 0; i
< ELEMENTSOF(m
->samples
); i
++)
399 if (m
->samples
[i
].delay
> 0 && m
->samples
[i
].delay
< m
->samples
[idx_min
].delay
)
403 for (i
= 0; i
< ELEMENTSOF(m
->samples
); i
++)
404 j
+= pow(m
->samples
[i
].offset
- m
->samples
[idx_min
].offset
, 2);
405 m
->samples_jitter
= sqrt(j
/ (ELEMENTSOF(m
->samples
) - 1));
407 /* ignore samples when resyncing */
411 /* always accept offset if we are farther off than the round-trip delay */
412 if (fabs(offset
) > delay
)
415 /* we need a few samples before looking at them */
416 if (m
->packet_count
< 4)
419 /* do not accept anything worse than the maximum possible error of the best sample */
420 if (fabs(offset
) > m
->samples
[idx_min
].delay
)
423 /* compare the difference between the current offset to the previous offset and jitter */
424 return fabs(offset
- m
->samples
[idx_cur
].offset
) > 3 * jitter
;
427 static void manager_adjust_poll(Manager
*m
, double offset
, bool spike
) {
430 if (m
->poll_resync
) {
431 m
->poll_interval_usec
= m
->poll_interval_min_usec
;
432 m
->poll_resync
= false;
436 /* set to minimal poll interval */
437 if (!spike
&& fabs(offset
) > NTP_ACCURACY_SEC
) {
438 m
->poll_interval_usec
= m
->poll_interval_min_usec
;
442 /* increase polling interval */
443 if (fabs(offset
) < NTP_ACCURACY_SEC
* 0.25) {
444 if (m
->poll_interval_usec
< m
->poll_interval_max_usec
)
445 m
->poll_interval_usec
*= 2;
449 /* decrease polling interval */
450 if (spike
|| fabs(offset
) > NTP_ACCURACY_SEC
* 0.75) {
451 if (m
->poll_interval_usec
> m
->poll_interval_min_usec
)
452 m
->poll_interval_usec
/= 2;
457 static int manager_receive_response(sd_event_source
*source
, int fd
, uint32_t revents
, void *userdata
) {
458 Manager
*m
= userdata
;
459 struct ntp_msg ntpmsg
;
463 .iov_len
= sizeof(ntpmsg
),
466 struct cmsghdr cmsghdr
;
467 uint8_t buf
[CMSG_SPACE(sizeof(struct timeval
))];
469 union sockaddr_union server_addr
;
470 struct msghdr msghdr
= {
473 .msg_control
= &control
,
474 .msg_controllen
= sizeof(control
),
475 .msg_name
= &server_addr
,
476 .msg_namelen
= sizeof(server_addr
),
478 struct cmsghdr
*cmsg
;
479 struct timespec
*recv_time
= NULL
;
481 double origin
, receive
, trans
, dest
;
482 double delay
, offset
;
483 double root_distance
;
491 if (revents
& (EPOLLHUP
|EPOLLERR
)) {
492 log_warning("Server connection returned error.");
493 return manager_connect(m
);
496 len
= recvmsg(fd
, &msghdr
, MSG_DONTWAIT
);
501 log_warning("Error receiving message. Disconnecting.");
502 return manager_connect(m
);
505 /* Too short or too long packet? */
506 if (iov
.iov_len
< sizeof(struct ntp_msg
) || (msghdr
.msg_flags
& MSG_TRUNC
)) {
507 log_warning("Invalid response from server. Disconnecting.");
508 return manager_connect(m
);
511 if (!m
->current_server_name
||
512 !m
->current_server_address
||
513 !sockaddr_equal(&server_addr
, &m
->current_server_address
->sockaddr
)) {
514 log_debug("Response from unknown server.");
518 CMSG_FOREACH(cmsg
, &msghdr
) {
519 if (cmsg
->cmsg_level
!= SOL_SOCKET
)
522 switch (cmsg
->cmsg_type
) {
523 case SCM_TIMESTAMPNS
:
524 recv_time
= (struct timespec
*) CMSG_DATA(cmsg
);
529 log_error("Invalid packet timestamp.");
534 log_debug("Unexpected reply. Ignoring.");
538 m
->missed_replies
= 0;
540 /* check our "time cookie" (we just stored nanoseconds in the fraction field) */
541 if (be32toh(ntpmsg
.origin_time
.sec
) != m
->trans_time
.tv_sec
+ OFFSET_1900_1970
||
542 be32toh(ntpmsg
.origin_time
.frac
) != (unsigned long) m
->trans_time
.tv_nsec
) {
543 log_debug("Invalid reply; not our transmit time. Ignoring.");
547 m
->event_timeout
= sd_event_source_unref(m
->event_timeout
);
549 if (be32toh(ntpmsg
.recv_time
.sec
) < TIME_EPOCH
+ OFFSET_1900_1970
||
550 be32toh(ntpmsg
.trans_time
.sec
) < TIME_EPOCH
+ OFFSET_1900_1970
) {
551 log_debug("Invalid reply, returned times before epoch. Ignoring.");
552 return manager_connect(m
);
555 if (NTP_FIELD_LEAP(ntpmsg
.field
) == NTP_LEAP_NOTINSYNC
||
556 ntpmsg
.stratum
== 0 || ntpmsg
.stratum
>= 16) {
557 log_debug("Server is not synchronized. Disconnecting.");
558 return manager_connect(m
);
561 if (!IN_SET(NTP_FIELD_VERSION(ntpmsg
.field
), 3, 4)) {
562 log_debug("Response NTPv%d. Disconnecting.", NTP_FIELD_VERSION(ntpmsg
.field
));
563 return manager_connect(m
);
566 if (NTP_FIELD_MODE(ntpmsg
.field
) != NTP_MODE_SERVER
) {
567 log_debug("Unsupported mode %d. Disconnecting.", NTP_FIELD_MODE(ntpmsg
.field
));
568 return manager_connect(m
);
571 root_distance
= ntp_ts_short_to_d(&ntpmsg
.root_delay
) / 2 + ntp_ts_short_to_d(&ntpmsg
.root_dispersion
);
572 if (root_distance
> (double) m
->max_root_distance_usec
/ (double) USEC_PER_SEC
) {
573 log_debug("Server has too large root distance. Disconnecting.");
574 return manager_connect(m
);
579 m
->retry_interval
= 0;
582 manager_listen_stop(m
);
584 /* announce leap seconds */
585 if (NTP_FIELD_LEAP(ntpmsg
.field
) & NTP_LEAP_PLUSSEC
)
587 else if (NTP_FIELD_LEAP(ntpmsg
.field
) & NTP_LEAP_MINUSSEC
)
593 * "Timestamp Name ID When Generated
594 * ------------------------------------------------------------
595 * Originate Timestamp T1 time request sent by client
596 * Receive Timestamp T2 time request received by server
597 * Transmit Timestamp T3 time reply sent by server
598 * Destination Timestamp T4 time reply received by client
600 * The round-trip delay, d, and system clock offset, t, are defined as:
601 * d = (T4 - T1) - (T3 - T2) t = ((T2 - T1) + (T3 - T4)) / 2"
603 origin
= ts_to_d(&m
->trans_time
) + OFFSET_1900_1970
;
604 receive
= ntp_ts_to_d(&ntpmsg
.recv_time
);
605 trans
= ntp_ts_to_d(&ntpmsg
.trans_time
);
606 dest
= ts_to_d(recv_time
) + OFFSET_1900_1970
;
608 offset
= ((receive
- origin
) + (trans
- dest
)) / 2;
609 delay
= (dest
- origin
) - (trans
- receive
);
611 spike
= manager_sample_spike_detection(m
, offset
, delay
);
613 manager_adjust_poll(m
, offset
, spike
);
615 log_debug("NTP response:\n"
620 " precision : %.6f sec (%d)\n"
621 " root distance: %.6f sec\n"
622 " reference : %.4s\n"
627 " offset : %+.3f sec\n"
628 " delay : %+.3f sec\n"
629 " packet count : %"PRIu64
"\n"
631 " poll interval: " USEC_FMT
"\n",
632 NTP_FIELD_LEAP(ntpmsg
.field
),
633 NTP_FIELD_VERSION(ntpmsg
.field
),
634 NTP_FIELD_MODE(ntpmsg
.field
),
636 exp2(ntpmsg
.precision
), ntpmsg
.precision
,
638 ntpmsg
.stratum
== 1 ? ntpmsg
.refid
: "n/a",
639 origin
- OFFSET_1900_1970
,
640 receive
- OFFSET_1900_1970
,
641 trans
- OFFSET_1900_1970
,
642 dest
- OFFSET_1900_1970
,
645 m
->samples_jitter
, spike
? " spike" : "",
646 m
->poll_interval_usec
/ USEC_PER_SEC
);
650 r
= manager_adjust_clock(m
, offset
, leap_sec
);
652 log_error_errno(r
, "Failed to call clock_adjtime(): %m");
655 log_debug("interval/delta/delay/jitter/drift " USEC_FMT
"s/%+.3fs/%.3fs/%.3fs/%+ippm%s",
656 m
->poll_interval_usec
/ USEC_PER_SEC
, offset
, delay
, m
->samples_jitter
, m
->drift_ppm
,
657 spike
? " (ignored)" : "");
660 _cleanup_free_
char *pretty
= NULL
;
664 server_address_pretty(m
->current_server_address
, &pretty
);
665 log_info("Synchronized to time server %s (%s).", strna(pretty
), m
->current_server_name
->string
);
666 sd_notifyf(false, "STATUS=Synchronized to time server %s (%s).", strna(pretty
), m
->current_server_name
->string
);
669 r
= manager_arm_timer(m
, m
->poll_interval_usec
);
671 return log_error_errno(r
, "Failed to rearm timer: %m");
676 static int manager_listen_setup(Manager
*m
) {
677 union sockaddr_union addr
= {};
678 static const int tos
= IPTOS_LOWDELAY
;
679 static const int on
= 1;
684 if (m
->server_socket
>= 0)
687 assert(!m
->event_receive
);
688 assert(m
->current_server_address
);
690 addr
.sa
.sa_family
= m
->current_server_address
->sockaddr
.sa
.sa_family
;
692 m
->server_socket
= socket(addr
.sa
.sa_family
, SOCK_DGRAM
| SOCK_CLOEXEC
, 0);
693 if (m
->server_socket
< 0)
696 r
= bind(m
->server_socket
, &addr
.sa
, m
->current_server_address
->socklen
);
700 r
= setsockopt(m
->server_socket
, SOL_SOCKET
, SO_TIMESTAMPNS
, &on
, sizeof(on
));
704 (void) setsockopt(m
->server_socket
, IPPROTO_IP
, IP_TOS
, &tos
, sizeof(tos
));
706 return sd_event_add_io(m
->event
, &m
->event_receive
, m
->server_socket
, EPOLLIN
, manager_receive_response
, m
);
709 static void manager_listen_stop(Manager
*m
) {
712 m
->event_receive
= sd_event_source_unref(m
->event_receive
);
713 m
->server_socket
= safe_close(m
->server_socket
);
716 static int manager_begin(Manager
*m
) {
717 _cleanup_free_
char *pretty
= NULL
;
721 assert_return(m
->current_server_name
, -EHOSTUNREACH
);
722 assert_return(m
->current_server_address
, -EHOSTUNREACH
);
725 m
->missed_replies
= NTP_MAX_MISSED_REPLIES
;
726 if (m
->poll_interval_usec
== 0)
727 m
->poll_interval_usec
= m
->poll_interval_min_usec
;
729 server_address_pretty(m
->current_server_address
, &pretty
);
730 log_debug("Connecting to time server %s (%s).", strna(pretty
), m
->current_server_name
->string
);
731 sd_notifyf(false, "STATUS=Connecting to time server %s (%s).", strna(pretty
), m
->current_server_name
->string
);
733 r
= manager_clock_watch_setup(m
);
737 return manager_send_request(m
);
740 void manager_set_server_name(Manager
*m
, ServerName
*n
) {
743 if (m
->current_server_name
== n
)
746 m
->current_server_name
= n
;
747 m
->current_server_address
= NULL
;
749 manager_disconnect(m
);
752 log_debug("Selected server %s.", n
->string
);
755 void manager_set_server_address(Manager
*m
, ServerAddress
*a
) {
758 if (m
->current_server_address
== a
)
761 m
->current_server_address
= a
;
762 /* If a is NULL, we are just clearing the address, without
763 * changing the name. Keep the existing name in that case. */
765 m
->current_server_name
= a
->name
;
767 manager_disconnect(m
);
770 _cleanup_free_
char *pretty
= NULL
;
771 server_address_pretty(a
, &pretty
);
772 log_debug("Selected address %s of server %s.", strna(pretty
), a
->name
->string
);
776 static int manager_resolve_handler(sd_resolve_query
*q
, int ret
, const struct addrinfo
*ai
, void *userdata
) {
777 Manager
*m
= userdata
;
782 assert(m
->current_server_name
);
784 m
->resolve_query
= sd_resolve_query_unref(m
->resolve_query
);
787 log_debug("Failed to resolve %s: %s", m
->current_server_name
->string
, gai_strerror(ret
));
790 return manager_connect(m
);
793 for (; ai
; ai
= ai
->ai_next
) {
794 _cleanup_free_
char *pretty
= NULL
;
798 assert(ai
->ai_addrlen
>= offsetof(struct sockaddr
, sa_data
));
800 if (!IN_SET(ai
->ai_addr
->sa_family
, AF_INET
, AF_INET6
)) {
801 log_warning("Unsuitable address protocol for %s", m
->current_server_name
->string
);
805 r
= server_address_new(m
->current_server_name
, &a
, (const union sockaddr_union
*) ai
->ai_addr
, ai
->ai_addrlen
);
807 return log_error_errno(r
, "Failed to add server address: %m");
809 server_address_pretty(a
, &pretty
);
810 log_debug("Resolved address %s for %s.", pretty
, m
->current_server_name
->string
);
813 if (!m
->current_server_name
->addresses
) {
814 log_error("Failed to find suitable address for host %s.", m
->current_server_name
->string
);
817 return manager_connect(m
);
820 manager_set_server_address(m
, m
->current_server_name
->addresses
);
822 return manager_begin(m
);
825 static int manager_retry_connect(sd_event_source
*source
, usec_t usec
, void *userdata
) {
826 Manager
*m
= userdata
;
830 return manager_connect(m
);
833 int manager_connect(Manager
*m
) {
838 manager_disconnect(m
);
840 m
->event_retry
= sd_event_source_unref(m
->event_retry
);
841 if (!ratelimit_test(&m
->ratelimit
)) {
842 log_debug("Slowing down attempts to contact servers.");
844 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
);
846 return log_error_errno(r
, "Failed to create retry timer: %m");
851 /* If we already are operating on some address, switch to the
853 if (m
->current_server_address
&& m
->current_server_address
->addresses_next
)
854 manager_set_server_address(m
, m
->current_server_address
->addresses_next
);
856 struct addrinfo hints
= {
857 .ai_flags
= AI_NUMERICSERV
|AI_ADDRCONFIG
,
858 .ai_socktype
= SOCK_DGRAM
,
861 /* Hmm, we are through all addresses, let's look for the next host instead */
862 if (m
->current_server_name
&& m
->current_server_name
->names_next
)
863 manager_set_server_name(m
, m
->current_server_name
->names_next
);
868 /* Our current server name list is exhausted,
869 * let's find the next one to iterate. First
870 * we try the system list, then the link list.
871 * After having processed the link list we
872 * jump back to the system list. However, if
873 * both lists are empty, we change to the
875 if (!m
->current_server_name
|| m
->current_server_name
->type
== SERVER_LINK
) {
876 f
= m
->system_servers
;
882 f
= m
->system_servers
;
888 f
= m
->fallback_servers
;
891 manager_set_server_name(m
, NULL
);
892 log_debug("No server found.");
896 if (restart
&& !m
->exhausted_servers
&& m
->poll_interval_usec
) {
897 log_debug("Waiting after exhausting servers.");
898 r
= sd_event_add_time(m
->event
, &m
->event_retry
, clock_boottime_or_monotonic(), now(clock_boottime_or_monotonic()) + m
->poll_interval_usec
, 0, manager_retry_connect
, m
);
900 return log_error_errno(r
, "Failed to create retry timer: %m");
902 m
->exhausted_servers
= true;
904 /* Increase the polling interval */
905 if (m
->poll_interval_usec
< m
->poll_interval_max_usec
)
906 m
->poll_interval_usec
*= 2;
911 m
->exhausted_servers
= false;
913 manager_set_server_name(m
, f
);
916 /* Tell the resolver to reread /etc/resolv.conf, in
917 * case it changed. */
920 /* Flush out any previously resolved addresses */
921 server_name_flush_addresses(m
->current_server_name
);
923 log_debug("Resolving %s...", m
->current_server_name
->string
);
925 r
= sd_resolve_getaddrinfo(m
->resolve
, &m
->resolve_query
, m
->current_server_name
->string
, "123", &hints
, manager_resolve_handler
, m
);
927 return log_error_errno(r
, "Failed to create resolver: %m");
932 r
= manager_begin(m
);
939 void manager_disconnect(Manager
*m
) {
942 m
->resolve_query
= sd_resolve_query_unref(m
->resolve_query
);
944 m
->event_timer
= sd_event_source_unref(m
->event_timer
);
946 manager_listen_stop(m
);
948 m
->event_clock_watch
= sd_event_source_unref(m
->event_clock_watch
);
949 m
->clock_watch_fd
= safe_close(m
->clock_watch_fd
);
951 m
->event_timeout
= sd_event_source_unref(m
->event_timeout
);
953 sd_notifyf(false, "STATUS=Idle.");
956 void manager_flush_server_names(Manager
*m
, ServerType t
) {
959 if (t
== SERVER_SYSTEM
)
960 while (m
->system_servers
)
961 server_name_free(m
->system_servers
);
963 if (t
== SERVER_LINK
)
964 while (m
->link_servers
)
965 server_name_free(m
->link_servers
);
967 if (t
== SERVER_FALLBACK
)
968 while (m
->fallback_servers
)
969 server_name_free(m
->fallback_servers
);
972 void manager_free(Manager
*m
) {
976 manager_disconnect(m
);
977 manager_flush_server_names(m
, SERVER_SYSTEM
);
978 manager_flush_server_names(m
, SERVER_LINK
);
979 manager_flush_server_names(m
, SERVER_FALLBACK
);
981 sd_event_source_unref(m
->event_retry
);
983 sd_event_source_unref(m
->network_event_source
);
984 sd_network_monitor_unref(m
->network_monitor
);
986 sd_resolve_unref(m
->resolve
);
987 sd_event_unref(m
->event
);
992 static int manager_network_read_link_servers(Manager
*m
) {
993 _cleanup_strv_free_
char **ntp
= NULL
;
996 bool changed
= false;
1001 r
= sd_network_get_ntp(&ntp
);
1005 LIST_FOREACH(names
, n
, m
->link_servers
)
1008 STRV_FOREACH(i
, ntp
) {
1011 LIST_FOREACH(names
, n
, m
->link_servers
)
1012 if (streq(n
->string
, *i
)) {
1019 r
= server_name_new(m
, NULL
, SERVER_LINK
, *i
);
1027 LIST_FOREACH_SAFE(names
, n
, nx
, m
->link_servers
)
1029 server_name_free(n
);
1036 manager_flush_server_names(m
, SERVER_LINK
);
1040 static int manager_network_event_handler(sd_event_source
*s
, int fd
, uint32_t revents
, void *userdata
) {
1041 Manager
*m
= userdata
;
1042 bool changed
, connected
, online
;
1047 sd_network_monitor_flush(m
->network_monitor
);
1049 changed
= !!manager_network_read_link_servers(m
);
1051 /* check if the machine is online */
1052 online
= network_is_online();
1054 /* check if the client is currently connected */
1055 connected
= m
->server_socket
>= 0 || m
->resolve_query
|| m
->exhausted_servers
;
1057 if (connected
&& !online
) {
1058 log_info("No network connectivity, watching for changes.");
1059 manager_disconnect(m
);
1061 } else if (!connected
&& online
&& changed
) {
1062 log_info("Network configuration changed, trying to establish connection.");
1064 if (m
->current_server_address
)
1065 r
= manager_begin(m
);
1067 r
= manager_connect(m
);
1075 static int manager_network_monitor_listen(Manager
*m
) {
1080 r
= sd_network_monitor_new(&m
->network_monitor
, NULL
);
1082 log_info("systemd does not appear to be running, not listening for systemd-networkd events.");
1088 fd
= sd_network_monitor_get_fd(m
->network_monitor
);
1092 events
= sd_network_monitor_get_events(m
->network_monitor
);
1096 r
= sd_event_add_io(m
->event
, &m
->network_event_source
, fd
, events
, manager_network_event_handler
, m
);
1103 int manager_new(Manager
**ret
) {
1104 _cleanup_(manager_freep
) Manager
*m
= NULL
;
1109 m
= new0(Manager
, 1);
1113 m
->max_root_distance_usec
= NTP_MAX_ROOT_DISTANCE
;
1114 m
->poll_interval_min_usec
= NTP_POLL_INTERVAL_MIN_USEC
;
1115 m
->poll_interval_max_usec
= NTP_POLL_INTERVAL_MAX_USEC
;
1117 m
->server_socket
= m
->clock_watch_fd
= -1;
1119 RATELIMIT_INIT(m
->ratelimit
, RATELIMIT_INTERVAL_USEC
, RATELIMIT_BURST
);
1121 r
= sd_event_default(&m
->event
);
1125 sd_event_add_signal(m
->event
, NULL
, SIGTERM
, NULL
, NULL
);
1126 sd_event_add_signal(m
->event
, NULL
, SIGINT
, NULL
, NULL
);
1128 sd_event_set_watchdog(m
->event
, true);
1130 r
= sd_resolve_default(&m
->resolve
);
1134 r
= sd_resolve_attach_event(m
->resolve
, m
->event
, 0);
1138 r
= manager_network_monitor_listen(m
);
1142 manager_network_read_link_servers(m
);