1 /* SPDX-License-Identifier: LGPL-2.1+ */
3 Copyright © 2014 Kay Sievers
8 #include <netinet/in.h>
9 #include <netinet/ip.h>
12 #include <sys/socket.h>
13 #include <sys/timerfd.h>
14 #include <sys/timex.h>
15 #include <sys/types.h>
18 #include "sd-daemon.h"
20 #include "alloc-util.h"
21 #include "dns-domain.h"
27 #include "network-util.h"
28 #include "ratelimit.h"
29 #include "socket-util.h"
30 #include "string-util.h"
32 #include "time-util.h"
33 #include "timesyncd-conf.h"
34 #include "timesyncd-manager.h"
38 #define ADJ_SETOFFSET 0x0100 /* add 'time' to current time */
41 /* expected accuracy of time synchronization; used to adjust the poll interval */
42 #define NTP_ACCURACY_SEC 0.2
45 * Maximum delta in seconds which the system clock is gradually adjusted
46 * (slewed) to approach the network time. Deltas larger that this are set by
47 * letting the system time jump. The kernel's limit for adjtime is 0.5s.
49 #define NTP_MAX_ADJUST 0.4
51 /* Default of maximum acceptable root distance in microseconds. */
52 #define NTP_MAX_ROOT_DISTANCE (5 * USEC_PER_SEC)
54 /* Maximum number of missed replies before selecting another source. */
55 #define NTP_MAX_MISSED_REPLIES 2
57 #define RETRY_USEC (30*USEC_PER_SEC)
58 #define RATELIMIT_INTERVAL_USEC (10*USEC_PER_SEC)
59 #define RATELIMIT_BURST 10
61 #define TIMEOUT_USEC (10*USEC_PER_SEC)
63 static int manager_arm_timer(Manager
*m
, usec_t next
);
64 static int manager_clock_watch_setup(Manager
*m
);
65 static int manager_listen_setup(Manager
*m
);
66 static void manager_listen_stop(Manager
*m
);
68 static double ntp_ts_short_to_d(const struct ntp_ts_short
*ts
) {
69 return be16toh(ts
->sec
) + (be16toh(ts
->frac
) / 65536.0);
72 static double ntp_ts_to_d(const struct ntp_ts
*ts
) {
73 return be32toh(ts
->sec
) + ((double)be32toh(ts
->frac
) / UINT_MAX
);
76 static double ts_to_d(const struct timespec
*ts
) {
77 return ts
->tv_sec
+ (1.0e-9 * ts
->tv_nsec
);
80 static int manager_timeout(sd_event_source
*source
, usec_t usec
, void *userdata
) {
81 _cleanup_free_
char *pretty
= NULL
;
82 Manager
*m
= userdata
;
85 assert(m
->current_server_name
);
86 assert(m
->current_server_address
);
88 server_address_pretty(m
->current_server_address
, &pretty
);
89 log_info("Timed out waiting for reply from %s (%s).", strna(pretty
), m
->current_server_name
->string
);
91 return manager_connect(m
);
94 static int manager_send_request(Manager
*m
) {
95 _cleanup_free_
char *pretty
= NULL
;
96 struct ntp_msg ntpmsg
= {
98 * "The client initializes the NTP message header, sends the request
99 * to the server, and strips the time of day from the Transmit
100 * Timestamp field of the reply. For this purpose, all the NTP
101 * header fields are set to 0, except the Mode, VN, and optional
102 * Transmit Timestamp fields."
104 .field
= NTP_FIELD(0, 4, NTP_MODE_CLIENT
),
110 assert(m
->current_server_name
);
111 assert(m
->current_server_address
);
113 m
->event_timeout
= sd_event_source_unref(m
->event_timeout
);
115 r
= manager_listen_setup(m
);
117 return log_warning_errno(r
, "Failed to setup connection socket: %m");
120 * Set transmit timestamp, remember it; the server will send that back
121 * as the origin timestamp and we have an indication that this is the
122 * matching answer to our request.
124 * The actual value does not matter, We do not care about the correct
125 * NTP UINT_MAX fraction; we just pass the plain nanosecond value.
127 assert_se(clock_gettime(clock_boottime_or_monotonic(), &m
->trans_time_mon
) >= 0);
128 assert_se(clock_gettime(CLOCK_REALTIME
, &m
->trans_time
) >= 0);
129 ntpmsg
.trans_time
.sec
= htobe32(m
->trans_time
.tv_sec
+ OFFSET_1900_1970
);
130 ntpmsg
.trans_time
.frac
= htobe32(m
->trans_time
.tv_nsec
);
132 server_address_pretty(m
->current_server_address
, &pretty
);
134 len
= sendto(m
->server_socket
, &ntpmsg
, sizeof(ntpmsg
), MSG_DONTWAIT
, &m
->current_server_address
->sockaddr
.sa
, m
->current_server_address
->socklen
);
135 if (len
== sizeof(ntpmsg
)) {
137 log_debug("Sent NTP request to %s (%s).", strna(pretty
), m
->current_server_name
->string
);
139 log_debug_errno(errno
, "Sending NTP request to %s (%s) failed: %m", strna(pretty
), m
->current_server_name
->string
);
140 return manager_connect(m
);
143 /* re-arm timer with increasing timeout, in case the packets never arrive back */
144 if (m
->retry_interval
> 0) {
145 if (m
->retry_interval
< m
->poll_interval_max_usec
)
146 m
->retry_interval
*= 2;
148 m
->retry_interval
= m
->poll_interval_min_usec
;
150 r
= manager_arm_timer(m
, m
->retry_interval
);
152 return log_error_errno(r
, "Failed to rearm timer: %m");
155 if (m
->missed_replies
> NTP_MAX_MISSED_REPLIES
) {
156 r
= sd_event_add_time(
159 clock_boottime_or_monotonic(),
160 now(clock_boottime_or_monotonic()) + TIMEOUT_USEC
, 0,
163 return log_error_errno(r
, "Failed to arm timeout timer: %m");
169 static int manager_timer(sd_event_source
*source
, usec_t usec
, void *userdata
) {
170 Manager
*m
= userdata
;
174 return manager_send_request(m
);
177 static int manager_arm_timer(Manager
*m
, usec_t next
) {
183 m
->event_timer
= sd_event_source_unref(m
->event_timer
);
187 if (m
->event_timer
) {
188 r
= sd_event_source_set_time(m
->event_timer
, now(clock_boottime_or_monotonic()) + next
);
192 return sd_event_source_set_enabled(m
->event_timer
, SD_EVENT_ONESHOT
);
195 return sd_event_add_time(
198 clock_boottime_or_monotonic(),
199 now(clock_boottime_or_monotonic()) + next
, 0,
203 static int manager_clock_watch(sd_event_source
*source
, int fd
, uint32_t revents
, void *userdata
) {
204 Manager
*m
= userdata
;
209 manager_clock_watch_setup(m
);
211 /* skip our own jumps */
218 log_debug("System time changed. Resyncing.");
219 m
->poll_resync
= true;
221 return manager_send_request(m
);
224 /* wake up when the system time changes underneath us */
225 static int manager_clock_watch_setup(Manager
*m
) {
230 m
->event_clock_watch
= sd_event_source_unref(m
->event_clock_watch
);
231 safe_close(m
->clock_watch_fd
);
233 m
->clock_watch_fd
= time_change_fd();
234 if (m
->clock_watch_fd
< 0)
235 return log_error_errno(m
->clock_watch_fd
, "Failed to create timerfd: %m");
237 r
= sd_event_add_io(m
->event
, &m
->event_clock_watch
, m
->clock_watch_fd
, EPOLLIN
, manager_clock_watch
, m
);
239 return log_error_errno(r
, "Failed to create clock watch event source: %m");
244 static int manager_adjust_clock(Manager
*m
, double offset
, int leap_sec
) {
245 struct timex tmx
= {};
251 * For small deltas, tell the kernel to gradually adjust the system
252 * clock to the NTP time, larger deltas are just directly set.
254 if (fabs(offset
) < NTP_MAX_ADJUST
) {
255 tmx
.modes
= ADJ_STATUS
| ADJ_NANO
| ADJ_OFFSET
| ADJ_TIMECONST
| ADJ_MAXERROR
| ADJ_ESTERROR
;
256 tmx
.status
= STA_PLL
;
257 tmx
.offset
= offset
* NSEC_PER_SEC
;
258 tmx
.constant
= log2i(m
->poll_interval_usec
/ USEC_PER_SEC
) - 4;
261 log_debug(" adjust (slew): %+.3f sec", offset
);
263 tmx
.modes
= ADJ_STATUS
| ADJ_NANO
| ADJ_SETOFFSET
| ADJ_MAXERROR
| ADJ_ESTERROR
;
265 /* ADJ_NANO uses nanoseconds in the microseconds field */
266 tmx
.time
.tv_sec
= (long)offset
;
267 tmx
.time
.tv_usec
= (offset
- tmx
.time
.tv_sec
) * NSEC_PER_SEC
;
271 /* the kernel expects -0.3s as {-1, 7000.000.000} */
272 if (tmx
.time
.tv_usec
< 0) {
273 tmx
.time
.tv_sec
-= 1;
274 tmx
.time
.tv_usec
+= NSEC_PER_SEC
;
278 log_debug(" adjust (jump): %+.3f sec", offset
);
282 * An unset STA_UNSYNC will enable the kernel's 11-minute mode,
283 * which syncs the system time periodically to the RTC.
285 * In case the RTC runs in local time, never touch the RTC,
286 * we have no way to properly handle daylight saving changes and
287 * mobile devices moving between time zones.
289 if (m
->rtc_local_time
)
290 tmx
.status
|= STA_UNSYNC
;
294 tmx
.status
|= STA_INS
;
297 tmx
.status
|= STA_DEL
;
301 r
= clock_adjtime(CLOCK_REALTIME
, &tmx
);
305 /* If touch fails, there isn't much we can do. Maybe it'll work next time. */
306 (void) touch("/var/lib/systemd/timesync/clock");
307 (void) touch("/run/systemd/timesync/synchronized");
309 m
->drift_freq
= tmx
.freq
;
311 log_debug(" status : %04i %s\n"
312 " time now : %"PRI_TIME
".%03"PRI_USEC
"\n"
313 " constant : %"PRI_TIMEX
"\n"
314 " offset : %+.3f sec\n"
315 " freq offset : %+"PRI_TIMEX
" (%+"PRI_TIMEX
" ppm)\n",
316 tmx
.status
, tmx
.status
& STA_UNSYNC
? "unsync" : "sync",
317 tmx
.time
.tv_sec
, tmx
.time
.tv_usec
/ NSEC_PER_MSEC
,
319 (double)tmx
.offset
/ NSEC_PER_SEC
,
320 tmx
.freq
, tmx
.freq
/ 65536);
325 static bool manager_sample_spike_detection(Manager
*m
, double offset
, double delay
) {
326 unsigned int i
, idx_cur
, idx_new
, idx_min
;
334 /* ignore initial sample */
335 if (m
->packet_count
== 1)
338 /* store the current data in our samples array */
339 idx_cur
= m
->samples_idx
;
340 idx_new
= (idx_cur
+ 1) % ELEMENTSOF(m
->samples
);
341 m
->samples_idx
= idx_new
;
342 m
->samples
[idx_new
].offset
= offset
;
343 m
->samples
[idx_new
].delay
= delay
;
345 /* calculate new jitter value from the RMS differences relative to the lowest delay sample */
346 jitter
= m
->samples_jitter
;
347 for (idx_min
= idx_cur
, i
= 0; i
< ELEMENTSOF(m
->samples
); i
++)
348 if (m
->samples
[i
].delay
> 0 && m
->samples
[i
].delay
< m
->samples
[idx_min
].delay
)
352 for (i
= 0; i
< ELEMENTSOF(m
->samples
); i
++)
353 j
+= pow(m
->samples
[i
].offset
- m
->samples
[idx_min
].offset
, 2);
354 m
->samples_jitter
= sqrt(j
/ (ELEMENTSOF(m
->samples
) - 1));
356 /* ignore samples when resyncing */
360 /* always accept offset if we are farther off than the round-trip delay */
361 if (fabs(offset
) > delay
)
364 /* we need a few samples before looking at them */
365 if (m
->packet_count
< 4)
368 /* do not accept anything worse than the maximum possible error of the best sample */
369 if (fabs(offset
) > m
->samples
[idx_min
].delay
)
372 /* compare the difference between the current offset to the previous offset and jitter */
373 return fabs(offset
- m
->samples
[idx_cur
].offset
) > 3 * jitter
;
376 static void manager_adjust_poll(Manager
*m
, double offset
, bool spike
) {
379 if (m
->poll_resync
) {
380 m
->poll_interval_usec
= m
->poll_interval_min_usec
;
381 m
->poll_resync
= false;
385 /* set to minimal poll interval */
386 if (!spike
&& fabs(offset
) > NTP_ACCURACY_SEC
) {
387 m
->poll_interval_usec
= m
->poll_interval_min_usec
;
391 /* increase polling interval */
392 if (fabs(offset
) < NTP_ACCURACY_SEC
* 0.25) {
393 if (m
->poll_interval_usec
< m
->poll_interval_max_usec
)
394 m
->poll_interval_usec
*= 2;
398 /* decrease polling interval */
399 if (spike
|| fabs(offset
) > NTP_ACCURACY_SEC
* 0.75) {
400 if (m
->poll_interval_usec
> m
->poll_interval_min_usec
)
401 m
->poll_interval_usec
/= 2;
406 static int manager_receive_response(sd_event_source
*source
, int fd
, uint32_t revents
, void *userdata
) {
407 Manager
*m
= userdata
;
408 struct ntp_msg ntpmsg
;
412 .iov_len
= sizeof(ntpmsg
),
415 struct cmsghdr cmsghdr
;
416 uint8_t buf
[CMSG_SPACE(sizeof(struct timeval
))];
418 union sockaddr_union server_addr
;
419 struct msghdr msghdr
= {
422 .msg_control
= &control
,
423 .msg_controllen
= sizeof(control
),
424 .msg_name
= &server_addr
,
425 .msg_namelen
= sizeof(server_addr
),
427 struct cmsghdr
*cmsg
;
428 struct timespec
*recv_time
= NULL
;
430 double origin
, receive
, trans
, dest
;
431 double delay
, offset
;
432 double root_distance
;
440 if (revents
& (EPOLLHUP
|EPOLLERR
)) {
441 log_warning("Server connection returned error.");
442 return manager_connect(m
);
445 len
= recvmsg(fd
, &msghdr
, MSG_DONTWAIT
);
450 log_warning("Error receiving message. Disconnecting.");
451 return manager_connect(m
);
454 /* Too short or too long packet? */
455 if (iov
.iov_len
< sizeof(struct ntp_msg
) || (msghdr
.msg_flags
& MSG_TRUNC
)) {
456 log_warning("Invalid response from server. Disconnecting.");
457 return manager_connect(m
);
460 if (!m
->current_server_name
||
461 !m
->current_server_address
||
462 !sockaddr_equal(&server_addr
, &m
->current_server_address
->sockaddr
)) {
463 log_debug("Response from unknown server.");
467 CMSG_FOREACH(cmsg
, &msghdr
) {
468 if (cmsg
->cmsg_level
!= SOL_SOCKET
)
471 switch (cmsg
->cmsg_type
) {
472 case SCM_TIMESTAMPNS
:
473 recv_time
= (struct timespec
*) CMSG_DATA(cmsg
);
478 log_error("Invalid packet timestamp.");
483 log_debug("Unexpected reply. Ignoring.");
487 m
->missed_replies
= 0;
489 /* check our "time cookie" (we just stored nanoseconds in the fraction field) */
490 if (be32toh(ntpmsg
.origin_time
.sec
) != m
->trans_time
.tv_sec
+ OFFSET_1900_1970
||
491 be32toh(ntpmsg
.origin_time
.frac
) != (unsigned long) m
->trans_time
.tv_nsec
) {
492 log_debug("Invalid reply; not our transmit time. Ignoring.");
496 m
->event_timeout
= sd_event_source_unref(m
->event_timeout
);
498 if (be32toh(ntpmsg
.recv_time
.sec
) < TIME_EPOCH
+ OFFSET_1900_1970
||
499 be32toh(ntpmsg
.trans_time
.sec
) < TIME_EPOCH
+ OFFSET_1900_1970
) {
500 log_debug("Invalid reply, returned times before epoch. Ignoring.");
501 return manager_connect(m
);
504 if (NTP_FIELD_LEAP(ntpmsg
.field
) == NTP_LEAP_NOTINSYNC
||
505 ntpmsg
.stratum
== 0 || ntpmsg
.stratum
>= 16) {
506 log_debug("Server is not synchronized. Disconnecting.");
507 return manager_connect(m
);
510 if (!IN_SET(NTP_FIELD_VERSION(ntpmsg
.field
), 3, 4)) {
511 log_debug("Response NTPv%d. Disconnecting.", NTP_FIELD_VERSION(ntpmsg
.field
));
512 return manager_connect(m
);
515 if (NTP_FIELD_MODE(ntpmsg
.field
) != NTP_MODE_SERVER
) {
516 log_debug("Unsupported mode %d. Disconnecting.", NTP_FIELD_MODE(ntpmsg
.field
));
517 return manager_connect(m
);
520 root_distance
= ntp_ts_short_to_d(&ntpmsg
.root_delay
) / 2 + ntp_ts_short_to_d(&ntpmsg
.root_dispersion
);
521 if (root_distance
> (double) m
->max_root_distance_usec
/ (double) USEC_PER_SEC
) {
522 log_debug("Server has too large root distance. Disconnecting.");
523 return manager_connect(m
);
528 m
->retry_interval
= 0;
531 manager_listen_stop(m
);
533 /* announce leap seconds */
534 if (NTP_FIELD_LEAP(ntpmsg
.field
) & NTP_LEAP_PLUSSEC
)
536 else if (NTP_FIELD_LEAP(ntpmsg
.field
) & NTP_LEAP_MINUSSEC
)
542 * "Timestamp Name ID When Generated
543 * ------------------------------------------------------------
544 * Originate Timestamp T1 time request sent by client
545 * Receive Timestamp T2 time request received by server
546 * Transmit Timestamp T3 time reply sent by server
547 * Destination Timestamp T4 time reply received by client
549 * The round-trip delay, d, and system clock offset, t, are defined as:
550 * d = (T4 - T1) - (T3 - T2) t = ((T2 - T1) + (T3 - T4)) / 2"
552 origin
= ts_to_d(&m
->trans_time
) + OFFSET_1900_1970
;
553 receive
= ntp_ts_to_d(&ntpmsg
.recv_time
);
554 trans
= ntp_ts_to_d(&ntpmsg
.trans_time
);
555 dest
= ts_to_d(recv_time
) + OFFSET_1900_1970
;
557 offset
= ((receive
- origin
) + (trans
- dest
)) / 2;
558 delay
= (dest
- origin
) - (trans
- receive
);
560 spike
= manager_sample_spike_detection(m
, offset
, delay
);
562 manager_adjust_poll(m
, offset
, spike
);
564 log_debug("NTP response:\n"
569 " precision : %.6f sec (%d)\n"
570 " root distance: %.6f sec\n"
571 " reference : %.4s\n"
576 " offset : %+.3f sec\n"
577 " delay : %+.3f sec\n"
578 " packet count : %"PRIu64
"\n"
580 " poll interval: " USEC_FMT
"\n",
581 NTP_FIELD_LEAP(ntpmsg
.field
),
582 NTP_FIELD_VERSION(ntpmsg
.field
),
583 NTP_FIELD_MODE(ntpmsg
.field
),
585 exp2(ntpmsg
.precision
), ntpmsg
.precision
,
587 ntpmsg
.stratum
== 1 ? ntpmsg
.refid
: "n/a",
588 origin
- OFFSET_1900_1970
,
589 receive
- OFFSET_1900_1970
,
590 trans
- OFFSET_1900_1970
,
591 dest
- OFFSET_1900_1970
,
594 m
->samples_jitter
, spike
? " spike" : "",
595 m
->poll_interval_usec
/ USEC_PER_SEC
);
599 r
= manager_adjust_clock(m
, offset
, leap_sec
);
601 log_error_errno(r
, "Failed to call clock_adjtime(): %m");
604 /* Save NTP response */
606 m
->origin_time
= m
->trans_time
;
607 m
->dest_time
= *recv_time
;
610 log_debug("interval/delta/delay/jitter/drift " USEC_FMT
"s/%+.3fs/%.3fs/%.3fs/%+"PRI_TIMEX
"ppm%s",
611 m
->poll_interval_usec
/ USEC_PER_SEC
, offset
, delay
, m
->samples_jitter
, m
->drift_freq
/ 65536,
612 spike
? " (ignored)" : "");
614 (void) sd_bus_emit_properties_changed(m
->bus
, "/org/freedesktop/timesync1", "org.freedesktop.timesync1.Manager", "NTPMessage", NULL
);
617 _cleanup_free_
char *pretty
= NULL
;
621 server_address_pretty(m
->current_server_address
, &pretty
);
622 log_info("Synchronized to time server %s (%s).", strna(pretty
), m
->current_server_name
->string
);
623 sd_notifyf(false, "STATUS=Synchronized to time server %s (%s).", strna(pretty
), m
->current_server_name
->string
);
626 r
= manager_arm_timer(m
, m
->poll_interval_usec
);
628 return log_error_errno(r
, "Failed to rearm timer: %m");
633 static int manager_listen_setup(Manager
*m
) {
634 union sockaddr_union addr
= {};
635 static const int tos
= IPTOS_LOWDELAY
;
636 static const int on
= 1;
641 if (m
->server_socket
>= 0)
644 assert(!m
->event_receive
);
645 assert(m
->current_server_address
);
647 addr
.sa
.sa_family
= m
->current_server_address
->sockaddr
.sa
.sa_family
;
649 m
->server_socket
= socket(addr
.sa
.sa_family
, SOCK_DGRAM
| SOCK_CLOEXEC
, 0);
650 if (m
->server_socket
< 0)
653 r
= bind(m
->server_socket
, &addr
.sa
, m
->current_server_address
->socklen
);
657 r
= setsockopt(m
->server_socket
, SOL_SOCKET
, SO_TIMESTAMPNS
, &on
, sizeof(on
));
661 (void) setsockopt(m
->server_socket
, IPPROTO_IP
, IP_TOS
, &tos
, sizeof(tos
));
663 return sd_event_add_io(m
->event
, &m
->event_receive
, m
->server_socket
, EPOLLIN
, manager_receive_response
, m
);
666 static void manager_listen_stop(Manager
*m
) {
669 m
->event_receive
= sd_event_source_unref(m
->event_receive
);
670 m
->server_socket
= safe_close(m
->server_socket
);
673 static int manager_begin(Manager
*m
) {
674 _cleanup_free_
char *pretty
= NULL
;
678 assert_return(m
->current_server_name
, -EHOSTUNREACH
);
679 assert_return(m
->current_server_address
, -EHOSTUNREACH
);
682 m
->missed_replies
= NTP_MAX_MISSED_REPLIES
;
683 if (m
->poll_interval_usec
== 0)
684 m
->poll_interval_usec
= m
->poll_interval_min_usec
;
686 server_address_pretty(m
->current_server_address
, &pretty
);
687 log_debug("Connecting to time server %s (%s).", strna(pretty
), m
->current_server_name
->string
);
688 sd_notifyf(false, "STATUS=Connecting to time server %s (%s).", strna(pretty
), m
->current_server_name
->string
);
690 r
= manager_clock_watch_setup(m
);
694 return manager_send_request(m
);
697 void manager_set_server_name(Manager
*m
, ServerName
*n
) {
700 if (m
->current_server_name
== n
)
703 m
->current_server_name
= n
;
704 m
->current_server_address
= NULL
;
706 manager_disconnect(m
);
709 log_debug("Selected server %s.", n
->string
);
712 void manager_set_server_address(Manager
*m
, ServerAddress
*a
) {
715 if (m
->current_server_address
== a
)
718 m
->current_server_address
= a
;
719 /* If a is NULL, we are just clearing the address, without
720 * changing the name. Keep the existing name in that case. */
722 m
->current_server_name
= a
->name
;
724 manager_disconnect(m
);
727 _cleanup_free_
char *pretty
= NULL
;
728 server_address_pretty(a
, &pretty
);
729 log_debug("Selected address %s of server %s.", strna(pretty
), a
->name
->string
);
733 static int manager_resolve_handler(sd_resolve_query
*q
, int ret
, const struct addrinfo
*ai
, void *userdata
) {
734 Manager
*m
= userdata
;
739 assert(m
->current_server_name
);
741 m
->resolve_query
= sd_resolve_query_unref(m
->resolve_query
);
744 log_debug("Failed to resolve %s: %s", m
->current_server_name
->string
, gai_strerror(ret
));
747 return manager_connect(m
);
750 for (; ai
; ai
= ai
->ai_next
) {
751 _cleanup_free_
char *pretty
= NULL
;
755 assert(ai
->ai_addrlen
>= offsetof(struct sockaddr
, sa_data
));
757 if (!IN_SET(ai
->ai_addr
->sa_family
, AF_INET
, AF_INET6
)) {
758 log_warning("Unsuitable address protocol for %s", m
->current_server_name
->string
);
762 r
= server_address_new(m
->current_server_name
, &a
, (const union sockaddr_union
*) ai
->ai_addr
, ai
->ai_addrlen
);
764 return log_error_errno(r
, "Failed to add server address: %m");
766 server_address_pretty(a
, &pretty
);
767 log_debug("Resolved address %s for %s.", pretty
, m
->current_server_name
->string
);
770 if (!m
->current_server_name
->addresses
) {
771 log_error("Failed to find suitable address for host %s.", m
->current_server_name
->string
);
774 return manager_connect(m
);
777 manager_set_server_address(m
, m
->current_server_name
->addresses
);
779 return manager_begin(m
);
782 static int manager_retry_connect(sd_event_source
*source
, usec_t usec
, void *userdata
) {
783 Manager
*m
= userdata
;
787 return manager_connect(m
);
790 int manager_connect(Manager
*m
) {
795 manager_disconnect(m
);
797 m
->event_retry
= sd_event_source_unref(m
->event_retry
);
798 if (!ratelimit_below(&m
->ratelimit
)) {
799 log_debug("Slowing down attempts to contact servers.");
801 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
);
803 return log_error_errno(r
, "Failed to create retry timer: %m");
808 /* If we already are operating on some address, switch to the
810 if (m
->current_server_address
&& m
->current_server_address
->addresses_next
)
811 manager_set_server_address(m
, m
->current_server_address
->addresses_next
);
813 struct addrinfo hints
= {
814 .ai_flags
= AI_NUMERICSERV
|AI_ADDRCONFIG
,
815 .ai_socktype
= SOCK_DGRAM
,
818 /* Hmm, we are through all addresses, let's look for the next host instead */
819 if (m
->current_server_name
&& m
->current_server_name
->names_next
)
820 manager_set_server_name(m
, m
->current_server_name
->names_next
);
825 /* Our current server name list is exhausted,
826 * let's find the next one to iterate. First
827 * we try the system list, then the link list.
828 * After having processed the link list we
829 * jump back to the system list. However, if
830 * both lists are empty, we change to the
832 if (!m
->current_server_name
|| m
->current_server_name
->type
== SERVER_LINK
) {
833 f
= m
->system_servers
;
839 f
= m
->system_servers
;
845 f
= m
->fallback_servers
;
848 manager_set_server_name(m
, NULL
);
849 log_debug("No server found.");
853 if (restart
&& !m
->exhausted_servers
&& m
->poll_interval_usec
) {
854 log_debug("Waiting after exhausting servers.");
855 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
);
857 return log_error_errno(r
, "Failed to create retry timer: %m");
859 m
->exhausted_servers
= true;
861 /* Increase the polling interval */
862 if (m
->poll_interval_usec
< m
->poll_interval_max_usec
)
863 m
->poll_interval_usec
*= 2;
868 m
->exhausted_servers
= false;
870 manager_set_server_name(m
, f
);
873 /* Tell the resolver to reread /etc/resolv.conf, in
874 * case it changed. */
877 /* Flush out any previously resolved addresses */
878 server_name_flush_addresses(m
->current_server_name
);
880 log_debug("Resolving %s...", m
->current_server_name
->string
);
882 r
= sd_resolve_getaddrinfo(m
->resolve
, &m
->resolve_query
, m
->current_server_name
->string
, "123", &hints
, manager_resolve_handler
, m
);
884 return log_error_errno(r
, "Failed to create resolver: %m");
889 r
= manager_begin(m
);
896 void manager_disconnect(Manager
*m
) {
899 m
->resolve_query
= sd_resolve_query_unref(m
->resolve_query
);
901 m
->event_timer
= sd_event_source_unref(m
->event_timer
);
903 manager_listen_stop(m
);
905 m
->event_clock_watch
= sd_event_source_unref(m
->event_clock_watch
);
906 m
->clock_watch_fd
= safe_close(m
->clock_watch_fd
);
908 m
->event_timeout
= sd_event_source_unref(m
->event_timeout
);
910 sd_notifyf(false, "STATUS=Idle.");
913 void manager_flush_server_names(Manager
*m
, ServerType t
) {
916 if (t
== SERVER_SYSTEM
)
917 while (m
->system_servers
)
918 server_name_free(m
->system_servers
);
920 if (t
== SERVER_LINK
)
921 while (m
->link_servers
)
922 server_name_free(m
->link_servers
);
924 if (t
== SERVER_FALLBACK
)
925 while (m
->fallback_servers
)
926 server_name_free(m
->fallback_servers
);
929 void manager_free(Manager
*m
) {
933 manager_disconnect(m
);
934 manager_flush_server_names(m
, SERVER_SYSTEM
);
935 manager_flush_server_names(m
, SERVER_LINK
);
936 manager_flush_server_names(m
, SERVER_FALLBACK
);
938 sd_event_source_unref(m
->event_retry
);
940 sd_event_source_unref(m
->network_event_source
);
941 sd_network_monitor_unref(m
->network_monitor
);
943 sd_resolve_unref(m
->resolve
);
944 sd_event_unref(m
->event
);
946 sd_bus_unref(m
->bus
);
951 static int manager_network_read_link_servers(Manager
*m
) {
952 _cleanup_strv_free_
char **ntp
= NULL
;
955 bool changed
= false;
960 r
= sd_network_get_ntp(&ntp
);
965 log_debug_errno(r
, "Failed to get link NTP servers: %m");
969 LIST_FOREACH(names
, n
, m
->link_servers
)
972 STRV_FOREACH(i
, ntp
) {
975 r
= dns_name_is_valid_or_address(*i
);
977 log_error_errno(r
, "Failed to check validity of NTP server name or address '%s': %m", *i
);
980 log_error("Invalid NTP server name or address, ignoring: %s", *i
);
984 LIST_FOREACH(names
, n
, m
->link_servers
)
985 if (streq(n
->string
, *i
)) {
992 r
= server_name_new(m
, NULL
, SERVER_LINK
, *i
);
1002 LIST_FOREACH_SAFE(names
, n
, nx
, m
->link_servers
)
1004 server_name_free(n
);
1011 manager_flush_server_names(m
, SERVER_LINK
);
1015 static bool manager_is_connected(Manager
*m
) {
1016 /* Return true when the manager is sending a request, resolving a server name, or
1017 * in a poll interval. */
1018 return m
->server_socket
>= 0 || m
->resolve_query
|| m
->event_timer
;
1021 static int manager_network_event_handler(sd_event_source
*s
, int fd
, uint32_t revents
, void *userdata
) {
1022 Manager
*m
= userdata
;
1023 bool changed
, connected
, online
;
1028 sd_network_monitor_flush(m
->network_monitor
);
1030 /* When manager_network_read_link_servers() failed, we assume that the servers are changed. */
1031 changed
= !!manager_network_read_link_servers(m
);
1033 /* check if the machine is online */
1034 online
= network_is_online();
1036 /* check if the client is currently connected */
1037 connected
= manager_is_connected(m
);
1039 if (connected
&& !online
) {
1040 log_info("No network connectivity, watching for changes.");
1041 manager_disconnect(m
);
1043 } else if ((!connected
|| changed
) && online
) {
1044 log_info("Network configuration changed, trying to establish connection.");
1046 if (m
->current_server_address
)
1047 r
= manager_begin(m
);
1049 r
= manager_connect(m
);
1057 static int manager_network_monitor_listen(Manager
*m
) {
1062 r
= sd_network_monitor_new(&m
->network_monitor
, NULL
);
1064 log_info("systemd does not appear to be running, not listening for systemd-networkd events.");
1070 fd
= sd_network_monitor_get_fd(m
->network_monitor
);
1074 events
= sd_network_monitor_get_events(m
->network_monitor
);
1078 r
= sd_event_add_io(m
->event
, &m
->network_event_source
, fd
, events
, manager_network_event_handler
, m
);
1085 int manager_new(Manager
**ret
) {
1086 _cleanup_(manager_freep
) Manager
*m
= NULL
;
1091 m
= new0(Manager
, 1);
1095 m
->max_root_distance_usec
= NTP_MAX_ROOT_DISTANCE
;
1096 m
->poll_interval_min_usec
= NTP_POLL_INTERVAL_MIN_USEC
;
1097 m
->poll_interval_max_usec
= NTP_POLL_INTERVAL_MAX_USEC
;
1099 m
->server_socket
= m
->clock_watch_fd
= -1;
1101 RATELIMIT_INIT(m
->ratelimit
, RATELIMIT_INTERVAL_USEC
, RATELIMIT_BURST
);
1103 r
= sd_event_default(&m
->event
);
1107 sd_event_add_signal(m
->event
, NULL
, SIGTERM
, NULL
, NULL
);
1108 sd_event_add_signal(m
->event
, NULL
, SIGINT
, NULL
, NULL
);
1110 sd_event_set_watchdog(m
->event
, true);
1112 r
= sd_resolve_default(&m
->resolve
);
1116 r
= sd_resolve_attach_event(m
->resolve
, m
->event
, 0);
1120 r
= manager_network_monitor_listen(m
);
1124 (void) manager_network_read_link_servers(m
);