| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <errno.h> |
| #include <math.h> |
| #include <netinet/in.h> |
| #include <netinet/ip.h> |
| #include <resolv.h> |
| #include <stdlib.h> |
| #include <sys/timerfd.h> |
| #include <sys/timex.h> |
| #include <sys/types.h> |
| |
| #include "sd-daemon.h" |
| #include "sd-messages.h" |
| |
| #include "alloc-util.h" |
| #include "bus-polkit.h" |
| #include "dns-domain.h" |
| #include "event-util.h" |
| #include "fd-util.h" |
| #include "format-util.h" |
| #include "fs-util.h" |
| #include "list.h" |
| #include "log.h" |
| #include "logarithm.h" |
| #include "network-util.h" |
| #include "ratelimit.h" |
| #include "resolve-private.h" |
| #include "socket-util.h" |
| #include "string-util.h" |
| #include "strv.h" |
| #include "time-util.h" |
| #include "timesyncd-conf.h" |
| #include "timesyncd-manager.h" |
| #include "user-util.h" |
| |
| #ifndef ADJ_SETOFFSET |
| #define ADJ_SETOFFSET 0x0100 /* add 'time' to current time */ |
| #endif |
| |
| /* Expected accuracy of time synchronization; used to adjust the poll interval */ |
| #define NTP_ACCURACY_SEC 0.2 |
| |
| /* |
| * Maximum delta in seconds which the system clock is gradually adjusted |
| * (slewed) to approach the network time. Deltas larger that this are set by |
| * letting the system time jump. The kernel's limit for adjtime is 0.5s. |
| */ |
| #define NTP_MAX_ADJUST 0.4 |
| |
| /* Default of maximum acceptable root distance in microseconds. */ |
| #define NTP_ROOT_DISTANCE_MAX_USEC (5 * USEC_PER_SEC) |
| |
| /* Maximum number of missed replies before selecting another source. */ |
| #define NTP_MAX_MISSED_REPLIES 2 |
| |
| #define RATELIMIT_INTERVAL_USEC (10*USEC_PER_SEC) |
| #define RATELIMIT_BURST 10 |
| |
| #define TIMEOUT_USEC (10*USEC_PER_SEC) |
| |
| static int manager_arm_timer(Manager *m, usec_t next); |
| static int manager_clock_watch_setup(Manager *m); |
| static int manager_listen_setup(Manager *m); |
| static void manager_listen_stop(Manager *m); |
| static int manager_save_time_and_rearm(Manager *m, usec_t t); |
| |
| static double ntp_ts_short_to_d(const struct ntp_ts_short *ts) { |
| return be16toh(ts->sec) + (be16toh(ts->frac) / 65536.0); |
| } |
| |
| static double ntp_ts_to_d(const struct ntp_ts *ts) { |
| return be32toh(ts->sec) + ((double)be32toh(ts->frac) / UINT_MAX); |
| } |
| |
| static double ts_to_d(const struct timespec *ts) { |
| return ts->tv_sec + (1.0e-9 * ts->tv_nsec); |
| } |
| |
| static uint32_t graceful_add_offset_1900_1970(time_t t) { |
| /* Adds OFFSET_1900_1970 to t and returns it as 32bit value. This is handles overflows |
| * gracefully in a deterministic and well-defined way by cutting off the top bits. */ |
| uint64_t a = (uint64_t) t + OFFSET_1900_1970; |
| return (uint32_t) (a & UINT64_C(0xFFFFFFFF)); |
| } |
| |
| static int manager_timeout(sd_event_source *source, usec_t usec, void *userdata) { |
| _cleanup_free_ char *pretty = NULL; |
| Manager *m = ASSERT_PTR(userdata); |
| |
| assert(m->current_server_name); |
| assert(m->current_server_address); |
| |
| server_address_pretty(m->current_server_address, &pretty); |
| log_info("Timed out waiting for reply from %s (%s).", strna(pretty), m->current_server_name->string); |
| |
| return manager_connect(m); |
| } |
| |
| static int manager_send_request(Manager *m) { |
| _cleanup_free_ char *pretty = NULL; |
| struct ntp_msg ntpmsg = { |
| /* |
| * "The client initializes the NTP message header, sends the request |
| * to the server, and strips the time of day from the Transmit |
| * Timestamp field of the reply. For this purpose, all the NTP |
| * header fields are set to 0, except the Mode, VN, and optional |
| * Transmit Timestamp fields." |
| */ |
| .field = NTP_FIELD(0, 4, NTP_MODE_CLIENT), |
| }; |
| ssize_t len; |
| int r; |
| |
| assert(m); |
| assert(m->current_server_name); |
| assert(m->current_server_address); |
| |
| m->event_timeout = sd_event_source_unref(m->event_timeout); |
| |
| r = manager_listen_setup(m); |
| if (r < 0) { |
| log_warning_errno(r, "Failed to set up connection socket: %m"); |
| return manager_connect(m); |
| } |
| |
| /* |
| * Set transmit timestamp, remember it; the server will send that back |
| * as the origin timestamp and we have an indication that this is the |
| * matching answer to our request. |
| * |
| * The actual value does not matter, We do not care about the correct |
| * NTP UINT_MAX fraction; we just pass the plain nanosecond value. |
| */ |
| assert_se(clock_gettime(CLOCK_BOOTTIME, &m->trans_time_mon) >= 0); |
| assert_se(clock_gettime(CLOCK_REALTIME, &m->trans_time) >= 0); |
| ntpmsg.trans_time.sec = htobe32(graceful_add_offset_1900_1970(m->trans_time.tv_sec)); |
| ntpmsg.trans_time.frac = htobe32(m->trans_time.tv_nsec); |
| |
| server_address_pretty(m->current_server_address, &pretty); |
| |
| len = sendto(m->server_socket, &ntpmsg, sizeof(ntpmsg), MSG_DONTWAIT, &m->current_server_address->sockaddr.sa, m->current_server_address->socklen); |
| if (len == sizeof(ntpmsg)) { |
| m->pending = true; |
| log_debug("Sent NTP request to %s (%s).", strna(pretty), m->current_server_name->string); |
| } else { |
| log_debug_errno(errno, "Sending NTP request to %s (%s) failed: %m", strna(pretty), m->current_server_name->string); |
| return manager_connect(m); |
| } |
| |
| /* re-arm timer with increasing timeout, in case the packets never arrive back */ |
| if (m->retry_interval == 0) |
| m->retry_interval = NTP_RETRY_INTERVAL_MIN_USEC; |
| else |
| m->retry_interval = MIN(m->retry_interval * 4/3, NTP_RETRY_INTERVAL_MAX_USEC); |
| |
| r = manager_arm_timer(m, m->retry_interval); |
| if (r < 0) |
| return log_error_errno(r, "Failed to rearm timer: %m"); |
| |
| m->missed_replies++; |
| if (m->missed_replies > NTP_MAX_MISSED_REPLIES) { |
| r = sd_event_add_time( |
| m->event, |
| &m->event_timeout, |
| CLOCK_BOOTTIME, |
| now(CLOCK_BOOTTIME) + TIMEOUT_USEC, 0, |
| manager_timeout, m); |
| if (r < 0) |
| return log_error_errno(r, "Failed to arm timeout timer: %m"); |
| } |
| |
| return 0; |
| } |
| |
| static int manager_timer(sd_event_source *source, usec_t usec, void *userdata) { |
| Manager *m = ASSERT_PTR(userdata); |
| |
| return manager_send_request(m); |
| } |
| |
| static int manager_arm_timer(Manager *m, usec_t next) { |
| int r; |
| |
| assert(m); |
| |
| if (next == 0) { |
| m->event_timer = sd_event_source_unref(m->event_timer); |
| return 0; |
| } |
| |
| if (m->event_timer) { |
| r = sd_event_source_set_time_relative(m->event_timer, next); |
| if (r < 0) |
| return r; |
| |
| return sd_event_source_set_enabled(m->event_timer, SD_EVENT_ONESHOT); |
| } |
| |
| return sd_event_add_time_relative( |
| m->event, |
| &m->event_timer, |
| CLOCK_BOOTTIME, |
| next, 0, |
| manager_timer, m); |
| } |
| |
| static int manager_clock_watch(sd_event_source *source, int fd, uint32_t revents, void *userdata) { |
| Manager *m = ASSERT_PTR(userdata); |
| |
| /* rearm timer */ |
| manager_clock_watch_setup(m); |
| |
| /* skip our own jumps */ |
| if (m->jumped) { |
| m->jumped = false; |
| return 0; |
| } |
| |
| /* resync */ |
| log_debug("System time changed. Resyncing."); |
| m->poll_resync = true; |
| |
| return manager_send_request(m); |
| } |
| |
| /* wake up when the system time changes underneath us */ |
| static int manager_clock_watch_setup(Manager *m) { |
| int r; |
| |
| assert(m); |
| |
| m->event_clock_watch = sd_event_source_disable_unref(m->event_clock_watch); |
| |
| r = event_add_time_change(m->event, &m->event_clock_watch, manager_clock_watch, m); |
| if (r < 0) |
| return log_error_errno(r, "Failed to create clock watch event source: %m"); |
| |
| return 0; |
| } |
| |
| static int manager_adjust_clock(Manager *m, double offset, int leap_sec) { |
| struct timex tmx; |
| |
| assert(m); |
| |
| /* For small deltas, tell the kernel to gradually adjust the system clock to the NTP time, larger |
| * deltas are just directly set. */ |
| if (fabs(offset) < NTP_MAX_ADJUST) { |
| tmx = (struct timex) { |
| .modes = ADJ_STATUS | ADJ_NANO | ADJ_OFFSET | ADJ_TIMECONST | ADJ_MAXERROR | ADJ_ESTERROR, |
| .status = STA_PLL, |
| .offset = offset * NSEC_PER_SEC, |
| .constant = log2i(m->poll_interval_usec / USEC_PER_SEC) - 4, |
| }; |
| |
| log_debug(" adjust (slew): %+.3f sec", offset); |
| } else { |
| tmx = (struct timex) { |
| .modes = ADJ_STATUS | ADJ_NANO | ADJ_SETOFFSET | ADJ_MAXERROR | ADJ_ESTERROR, |
| |
| /* ADJ_NANO uses nanoseconds in the microseconds field */ |
| .time.tv_sec = (long)offset, |
| .time.tv_usec = (offset - (double) (long) offset) * NSEC_PER_SEC, |
| }; |
| |
| /* the kernel expects -0.3s as {-1, 7000.000.000} */ |
| if (tmx.time.tv_usec < 0) { |
| tmx.time.tv_sec -= 1; |
| tmx.time.tv_usec += NSEC_PER_SEC; |
| } |
| |
| m->jumped = true; |
| log_debug(" adjust (jump): %+.3f sec", offset); |
| } |
| |
| /* An unset STA_UNSYNC will enable the kernel's 11-minute mode, which syncs the system time |
| * periodically to the RTC. |
| * |
| * In case the RTC runs in local time, never touch the RTC, we have no way to properly handle |
| * daylight saving changes and mobile devices moving between time zones. */ |
| if (m->rtc_local_time) |
| tmx.status |= STA_UNSYNC; |
| |
| switch (leap_sec) { |
| case 1: |
| tmx.status |= STA_INS; |
| break; |
| case -1: |
| tmx.status |= STA_DEL; |
| break; |
| } |
| |
| if (clock_adjtime(CLOCK_REALTIME, &tmx) < 0) |
| return -errno; |
| |
| m->drift_freq = tmx.freq; |
| |
| log_debug(" status : %04i %s\n" |
| " time now : %"PRI_TIME".%03"PRI_USEC"\n" |
| " constant : %"PRI_TIMEX"\n" |
| " offset : %+.3f sec\n" |
| " freq offset : %+"PRI_TIMEX" (%+"PRI_TIMEX" ppm)\n", |
| tmx.status, tmx.status & STA_UNSYNC ? "unsync" : "sync", |
| tmx.time.tv_sec, tmx.time.tv_usec / NSEC_PER_MSEC, |
| tmx.constant, |
| (double)tmx.offset / NSEC_PER_SEC, |
| tmx.freq, tmx.freq / 65536); |
| |
| return 0; |
| } |
| |
| static bool manager_sample_spike_detection(Manager *m, double offset, double delay) { |
| unsigned i, idx_cur, idx_new, idx_min; |
| double jitter; |
| double j; |
| |
| assert(m); |
| |
| m->packet_count++; |
| |
| /* ignore initial sample */ |
| if (m->packet_count == 1) |
| return false; |
| |
| /* store the current data in our samples array */ |
| idx_cur = m->samples_idx; |
| idx_new = (idx_cur + 1) % ELEMENTSOF(m->samples); |
| m->samples_idx = idx_new; |
| m->samples[idx_new].offset = offset; |
| m->samples[idx_new].delay = delay; |
| |
| /* calculate new jitter value from the RMS differences relative to the lowest delay sample */ |
| jitter = m->samples_jitter; |
| for (idx_min = idx_cur, i = 0; i < ELEMENTSOF(m->samples); i++) |
| if (m->samples[i].delay > 0 && m->samples[i].delay < m->samples[idx_min].delay) |
| idx_min = i; |
| |
| j = 0; |
| for (i = 0; i < ELEMENTSOF(m->samples); i++) |
| j += pow(m->samples[i].offset - m->samples[idx_min].offset, 2); |
| m->samples_jitter = sqrt(j / (ELEMENTSOF(m->samples) - 1)); |
| |
| /* ignore samples when resyncing */ |
| if (m->poll_resync) |
| return false; |
| |
| /* always accept offset if we are farther off than the round-trip delay */ |
| if (fabs(offset) > delay) |
| return false; |
| |
| /* we need a few samples before looking at them */ |
| if (m->packet_count < 4) |
| return false; |
| |
| /* do not accept anything worse than the maximum possible error of the best sample */ |
| if (fabs(offset) > m->samples[idx_min].delay) |
| return true; |
| |
| /* compare the difference between the current offset to the previous offset and jitter */ |
| return fabs(offset - m->samples[idx_cur].offset) > 3 * jitter; |
| } |
| |
| static void manager_adjust_poll(Manager *m, double offset, bool spike) { |
| assert(m); |
| |
| if (m->poll_resync) { |
| m->poll_interval_usec = m->poll_interval_min_usec; |
| m->poll_resync = false; |
| return; |
| } |
| |
| /* set to minimal poll interval */ |
| if (!spike && fabs(offset) > NTP_ACCURACY_SEC) { |
| m->poll_interval_usec = m->poll_interval_min_usec; |
| return; |
| } |
| |
| /* increase polling interval */ |
| if (fabs(offset) < NTP_ACCURACY_SEC * 0.25) { |
| if (m->poll_interval_usec < m->poll_interval_max_usec) |
| m->poll_interval_usec *= 2; |
| return; |
| } |
| |
| /* decrease polling interval */ |
| if (spike || fabs(offset) > NTP_ACCURACY_SEC * 0.75) { |
| if (m->poll_interval_usec > m->poll_interval_min_usec) |
| m->poll_interval_usec /= 2; |
| return; |
| } |
| } |
| |
| static int manager_receive_response(sd_event_source *source, int fd, uint32_t revents, void *userdata) { |
| Manager *m = ASSERT_PTR(userdata); |
| struct ntp_msg ntpmsg; |
| |
| struct iovec iov = { |
| .iov_base = &ntpmsg, |
| .iov_len = sizeof(ntpmsg), |
| }; |
| /* This needs to be initialized with zero. See #20741. */ |
| CMSG_BUFFER_TYPE(CMSG_SPACE_TIMESPEC) control = {}; |
| union sockaddr_union 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 timespec *recv_time = NULL; |
| triple_timestamp dts; |
| ssize_t len; |
| double origin, receive, trans, dest, delay, offset, root_distance; |
| bool spike; |
| int leap_sec, r; |
| |
| assert(source); |
| |
| if (revents & (EPOLLHUP|EPOLLERR)) { |
| log_warning("Server connection returned error."); |
| return manager_connect(m); |
| } |
| |
| len = recvmsg_safe(fd, &msghdr, MSG_DONTWAIT); |
| if (len == -EAGAIN) |
| return 0; |
| if (len < 0) { |
| log_warning_errno(len, "Error receiving message, disconnecting: %m"); |
| return manager_connect(m); |
| } |
| |
| /* Too short or too long packet? */ |
| if (iov.iov_len < sizeof(struct ntp_msg) || (msghdr.msg_flags & MSG_TRUNC)) { |
| log_warning("Invalid response from server. Disconnecting."); |
| return manager_connect(m); |
| } |
| |
| if (!m->current_server_name || |
| !m->current_server_address || |
| !sockaddr_equal(&server_addr, &m->current_server_address->sockaddr)) { |
| log_debug("Response from unknown server."); |
| return 0; |
| } |
| |
| recv_time = CMSG_FIND_DATA(&msghdr, SOL_SOCKET, SCM_TIMESTAMPNS, struct timespec); |
| if (!recv_time) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Packet timestamp missing."); |
| |
| if (!m->pending) { |
| log_debug("Unexpected reply. Ignoring."); |
| return 0; |
| } |
| |
| m->missed_replies = 0; |
| |
| /* check our "time cookie" (we just stored nanoseconds in the fraction field) */ |
| if (be32toh(ntpmsg.origin_time.sec) != graceful_add_offset_1900_1970(m->trans_time.tv_sec) || |
| be32toh(ntpmsg.origin_time.frac) != (unsigned long) m->trans_time.tv_nsec) { |
| log_debug("Invalid reply; not our transmit time. Ignoring."); |
| return 0; |
| } |
| |
| m->event_timeout = sd_event_source_unref(m->event_timeout); |
| |
| if (be32toh(ntpmsg.recv_time.sec) < TIME_EPOCH + OFFSET_1900_1970 || |
| be32toh(ntpmsg.trans_time.sec) < TIME_EPOCH + OFFSET_1900_1970) { |
| log_debug("Invalid reply, returned times before epoch. Ignoring."); |
| return manager_connect(m); |
| } |
| |
| if (NTP_FIELD_LEAP(ntpmsg.field) == NTP_LEAP_NOTINSYNC || |
| ntpmsg.stratum == 0 || ntpmsg.stratum >= 16) { |
| log_debug("Server is not synchronized. Disconnecting."); |
| return manager_connect(m); |
| } |
| |
| if (!IN_SET(NTP_FIELD_VERSION(ntpmsg.field), 3, 4)) { |
| log_debug("Response NTPv%d. Disconnecting.", NTP_FIELD_VERSION(ntpmsg.field)); |
| return manager_connect(m); |
| } |
| |
| if (NTP_FIELD_MODE(ntpmsg.field) != NTP_MODE_SERVER) { |
| log_debug("Unsupported mode %d. Disconnecting.", NTP_FIELD_MODE(ntpmsg.field)); |
| return manager_connect(m); |
| } |
| |
| root_distance = ntp_ts_short_to_d(&ntpmsg.root_delay) / 2 + ntp_ts_short_to_d(&ntpmsg.root_dispersion); |
| if (root_distance > (double) m->root_distance_max_usec / (double) USEC_PER_SEC) { |
| log_info("Server has too large root distance. Disconnecting."); |
| return manager_connect(m); |
| } |
| |
| /* valid packet */ |
| m->pending = false; |
| m->retry_interval = 0; |
| |
| /* Stop listening */ |
| manager_listen_stop(m); |
| |
| /* 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 round-trip delay, d, and system clock offset, t, are defined as: |
| * d = (T4 - T1) - (T3 - T2) t = ((T2 - T1) + (T3 - T4)) / 2" |
| */ |
| origin = ts_to_d(&m->trans_time) + OFFSET_1900_1970; |
| receive = ntp_ts_to_d(&ntpmsg.recv_time); |
| trans = ntp_ts_to_d(&ntpmsg.trans_time); |
| dest = ts_to_d(recv_time) + OFFSET_1900_1970; |
| |
| offset = ((receive - origin) + (trans - dest)) / 2; |
| delay = (dest - origin) - (trans - receive); |
| |
| spike = manager_sample_spike_detection(m, offset, delay); |
| |
| manager_adjust_poll(m, offset, spike); |
| |
| log_debug("NTP response:\n" |
| " leap : %i\n" |
| " version : %i\n" |
| " mode : %i\n" |
| " stratum : %u\n" |
| " precision : %.6f sec (%i)\n" |
| " root distance: %.6f sec\n" |
| " reference : %.4s\n" |
| " origin : %.3f\n" |
| " receive : %.3f\n" |
| " transmit : %.3f\n" |
| " dest : %.3f\n" |
| " offset : %+.3f sec\n" |
| " delay : %+.3f sec\n" |
| " packet count : %"PRIu64"\n" |
| " jitter : %.3f%s\n" |
| " poll interval: " USEC_FMT "\n", |
| NTP_FIELD_LEAP(ntpmsg.field), |
| NTP_FIELD_VERSION(ntpmsg.field), |
| NTP_FIELD_MODE(ntpmsg.field), |
| ntpmsg.stratum, |
| exp2(ntpmsg.precision), ntpmsg.precision, |
| root_distance, |
| ntpmsg.stratum == 1 ? ntpmsg.refid : "n/a", |
| origin - OFFSET_1900_1970, |
| receive - OFFSET_1900_1970, |
| trans - OFFSET_1900_1970, |
| dest - OFFSET_1900_1970, |
| offset, delay, |
| m->packet_count, |
| m->samples_jitter, spike ? " spike" : "", |
| m->poll_interval_usec / USEC_PER_SEC); |
| |
| /* Get current monotonic/realtime clocks immediately before adjusting the latter */ |
| triple_timestamp_get(&dts); |
| |
| if (!spike) { |
| /* Fix up our idea of the time. */ |
| dts.realtime = (usec_t) (dts.realtime + offset * USEC_PER_SEC); |
| |
| r = manager_adjust_clock(m, offset, leap_sec); |
| if (r < 0) |
| log_error_errno(r, "Failed to call clock_adjtime(): %m"); |
| |
| (void) manager_save_time_and_rearm(m, dts.realtime); |
| |
| /* If touch fails, there isn't much we can do. Maybe it'll work next time. */ |
| r = touch("/run/systemd/timesync/synchronized"); |
| if (r < 0) |
| log_debug_errno(r, "Failed to touch /run/systemd/timesync/synchronized, ignoring: %m"); |
| } |
| |
| /* Save NTP response */ |
| m->ntpmsg = ntpmsg; |
| m->origin_time = m->trans_time; |
| m->dest_time = *recv_time; |
| m->spike = spike; |
| |
| log_debug("interval/delta/delay/jitter/drift " USEC_FMT "s/%+.3fs/%.3fs/%.3fs/%+"PRIi64"ppm%s", |
| m->poll_interval_usec / USEC_PER_SEC, offset, delay, m->samples_jitter, m->drift_freq / 65536, |
| spike ? " (ignored)" : ""); |
| |
| if (sd_bus_is_ready(m->bus) > 0) |
| (void) sd_bus_emit_properties_changed( |
| m->bus, |
| "/org/freedesktop/timesync1", |
| "org.freedesktop.timesync1.Manager", |
| "NTPMessage", |
| NULL); |
| |
| if (!m->talking) { |
| _cleanup_free_ char *pretty = NULL; |
| |
| m->talking = true; |
| |
| (void) server_address_pretty(m->current_server_address, &pretty); |
| |
| log_info("Contacted time server %s (%s).", strna(pretty), m->current_server_name->string); |
| (void) sd_notifyf(false, "STATUS=Contacted time server %s (%s).", strna(pretty), m->current_server_name->string); |
| } |
| |
| if (!spike && !m->synchronized) { |
| m->synchronized = true; |
| |
| log_struct(LOG_INFO, |
| LOG_MESSAGE("Initial clock synchronization to %s.", |
| FORMAT_TIMESTAMP_STYLE(dts.realtime, TIMESTAMP_US)), |
| "MESSAGE_ID=" SD_MESSAGE_TIME_SYNC_STR, |
| "MONOTONIC_USEC=" USEC_FMT, dts.monotonic, |
| "REALTIME_USEC=" USEC_FMT, dts.realtime, |
| "BOOTIME_USEC=" USEC_FMT, dts.boottime); |
| } |
| |
| r = manager_arm_timer(m, m->poll_interval_usec); |
| if (r < 0) |
| return log_error_errno(r, "Failed to rearm timer: %m"); |
| |
| return 0; |
| } |
| |
| static int manager_listen_setup(Manager *m) { |
| union sockaddr_union addr = {}; |
| int r; |
| |
| assert(m); |
| |
| if (m->server_socket >= 0) |
| return 0; |
| |
| assert(!m->event_receive); |
| assert(m->current_server_address); |
| |
| addr.sa.sa_family = m->current_server_address->sockaddr.sa.sa_family; |
| |
| m->server_socket = socket(addr.sa.sa_family, SOCK_DGRAM | SOCK_CLOEXEC, 0); |
| if (m->server_socket < 0) |
| return -errno; |
| |
| r = bind(m->server_socket, &addr.sa, m->current_server_address->socklen); |
| if (r < 0) |
| return -errno; |
| |
| r = setsockopt_int(m->server_socket, SOL_SOCKET, SO_TIMESTAMPNS, true); |
| if (r < 0) |
| return r; |
| |
| if (addr.sa.sa_family == AF_INET) |
| (void) setsockopt_int(m->server_socket, IPPROTO_IP, IP_TOS, IPTOS_LOWDELAY); |
| |
| return sd_event_add_io(m->event, &m->event_receive, m->server_socket, EPOLLIN, manager_receive_response, m); |
| } |
| |
| static void manager_listen_stop(Manager *m) { |
| assert(m); |
| |
| m->event_receive = sd_event_source_unref(m->event_receive); |
| m->server_socket = safe_close(m->server_socket); |
| } |
| |
| static int manager_begin(Manager *m) { |
| _cleanup_free_ char *pretty = NULL; |
| int r; |
| |
| assert(m); |
| assert_return(m->current_server_name, -EHOSTUNREACH); |
| assert_return(m->current_server_address, -EHOSTUNREACH); |
| |
| m->talking = false; |
| m->missed_replies = NTP_MAX_MISSED_REPLIES; |
| if (m->poll_interval_usec == 0) |
| m->poll_interval_usec = m->poll_interval_min_usec; |
| |
| server_address_pretty(m->current_server_address, &pretty); |
| log_debug("Connecting to time server %s (%s).", strna(pretty), m->current_server_name->string); |
| (void) sd_notifyf(false, "STATUS=Connecting to time server %s (%s).", strna(pretty), m->current_server_name->string); |
| |
| r = manager_clock_watch_setup(m); |
| if (r < 0) |
| return r; |
| |
| return manager_send_request(m); |
| } |
| |
| void manager_set_server_name(Manager *m, ServerName *n) { |
| assert(m); |
| |
| if (m->current_server_name == n) |
| return; |
| |
| m->current_server_name = n; |
| m->current_server_address = NULL; |
| |
| manager_disconnect(m); |
| |
| if (n) |
| log_debug("Selected server %s.", n->string); |
| } |
| |
| void manager_set_server_address(Manager *m, ServerAddress *a) { |
| assert(m); |
| |
| if (m->current_server_address == a) |
| return; |
| |
| m->current_server_address = a; |
| /* If a is NULL, we are just clearing the address, without |
| * changing the name. Keep the existing name in that case. */ |
| if (a) |
| m->current_server_name = a->name; |
| |
| manager_disconnect(m); |
| |
| if (a) { |
| _cleanup_free_ char *pretty = NULL; |
| server_address_pretty(a, &pretty); |
| log_debug("Selected address %s of server %s.", strna(pretty), a->name->string); |
| } |
| } |
| |
| static int manager_resolve_handler(sd_resolve_query *q, int ret, const struct addrinfo *ai, Manager *m) { |
| int r; |
| |
| assert(q); |
| assert(m); |
| assert(m->current_server_name); |
| |
| m->resolve_query = sd_resolve_query_unref(m->resolve_query); |
| |
| if (ret != 0) { |
| log_debug("Failed to resolve %s: %s", m->current_server_name->string, gai_strerror(ret)); |
| |
| /* Try next host */ |
| return manager_connect(m); |
| } |
| |
| for (; ai; ai = ai->ai_next) { |
| _cleanup_free_ char *pretty = NULL; |
| ServerAddress *a; |
| |
| assert(ai->ai_addr); |
| assert(ai->ai_addrlen >= offsetof(struct sockaddr, sa_data)); |
| |
| if (!IN_SET(ai->ai_addr->sa_family, AF_INET, AF_INET6)) { |
| log_debug("Ignoring unsuitable address protocol for %s.", m->current_server_name->string); |
| continue; |
| } |
| |
| r = server_address_new(m->current_server_name, &a, (const union sockaddr_union*) ai->ai_addr, ai->ai_addrlen); |
| if (r < 0) |
| return log_error_errno(r, "Failed to add server address: %m"); |
| |
| server_address_pretty(a, &pretty); |
| log_debug("Resolved address %s for %s.", pretty, m->current_server_name->string); |
| } |
| |
| if (!m->current_server_name->addresses) { |
| log_error("Failed to find suitable address for host %s.", m->current_server_name->string); |
| |
| /* Try next host */ |
| return manager_connect(m); |
| } |
| |
| manager_set_server_address(m, m->current_server_name->addresses); |
| |
| return manager_begin(m); |
| } |
| |
| static int manager_retry_connect(sd_event_source *source, usec_t usec, void *userdata) { |
| Manager *m = ASSERT_PTR(userdata); |
| |
| return manager_connect(m); |
| } |
| |
| int manager_connect(Manager *m) { |
| int r; |
| |
| assert(m); |
| |
| manager_disconnect(m); |
| |
| m->event_retry = sd_event_source_unref(m->event_retry); |
| if (!ratelimit_below(&m->ratelimit)) { |
| log_debug("Delaying attempts to contact servers."); |
| |
| r = sd_event_add_time_relative(m->event, &m->event_retry, CLOCK_BOOTTIME, m->connection_retry_usec, |
| 0, manager_retry_connect, m); |
| if (r < 0) |
| return log_error_errno(r, "Failed to create retry timer: %m"); |
| |
| return 0; |
| } |
| |
| /* If we already are operating on some address, switch to the |
| * next one. */ |
| if (m->current_server_address && m->current_server_address->addresses_next) |
| manager_set_server_address(m, m->current_server_address->addresses_next); |
| else { |
| /* Hmm, we are through all addresses, let's look for the next host instead */ |
| if (m->current_server_name && m->current_server_name->names_next) |
| manager_set_server_name(m, m->current_server_name->names_next); |
| else { |
| ServerName *f; |
| bool restart = true; |
| |
| /* Our current server name list is exhausted, |
| * let's find the next one to iterate. First we try the runtime list, then the system list, |
| * then the link list. After having processed the link list we jump back to the system list |
| * if no runtime server list. |
| * However, if all lists are empty, we change to the fallback list. */ |
| if (!m->current_server_name || m->current_server_name->type == SERVER_LINK) { |
| f = m->runtime_servers; |
| if (!f) |
| f = m->system_servers; |
| if (!f) |
| f = m->link_servers; |
| } else { |
| f = m->link_servers; |
| if (f) |
| restart = false; |
| else { |
| f = m->runtime_servers; |
| if (!f) |
| f = m->system_servers; |
| } |
| } |
| |
| if (!f) |
| f = m->fallback_servers; |
| |
| if (!f) { |
| manager_set_server_name(m, NULL); |
| log_debug("No server found."); |
| return 0; |
| } |
| |
| if (restart && !m->exhausted_servers && m->poll_interval_usec > 0) { |
| log_debug("Waiting after exhausting servers."); |
| r = sd_event_add_time_relative(m->event, &m->event_retry, CLOCK_BOOTTIME, m->poll_interval_usec, 0, manager_retry_connect, m); |
| if (r < 0) |
| return log_error_errno(r, "Failed to create retry timer: %m"); |
| |
| m->exhausted_servers = true; |
| |
| /* Increase the polling interval */ |
| if (m->poll_interval_usec < m->poll_interval_max_usec) |
| m->poll_interval_usec *= 2; |
| |
| return 0; |
| } |
| |
| m->exhausted_servers = false; |
| |
| manager_set_server_name(m, f); |
| } |
| |
| /* Tell the resolver to reread /etc/resolv.conf, in |
| * case it changed. */ |
| res_init(); |
| |
| /* Flush out any previously resolved addresses */ |
| server_name_flush_addresses(m->current_server_name); |
| |
| log_debug("Resolving %s...", m->current_server_name->string); |
| |
| struct addrinfo hints = { |
| .ai_flags = AI_NUMERICSERV|AI_ADDRCONFIG, |
| .ai_socktype = SOCK_DGRAM, |
| .ai_family = socket_ipv6_is_supported() ? AF_UNSPEC : AF_INET, |
| }; |
| |
| r = resolve_getaddrinfo(m->resolve, &m->resolve_query, m->current_server_name->string, "123", &hints, manager_resolve_handler, NULL, m); |
| if (r < 0) |
| return log_error_errno(r, "Failed to create resolver: %m"); |
| |
| return 1; |
| } |
| |
| r = manager_begin(m); |
| if (r < 0) |
| return r; |
| |
| return 1; |
| } |
| |
| void manager_disconnect(Manager *m) { |
| assert(m); |
| |
| m->resolve_query = sd_resolve_query_unref(m->resolve_query); |
| |
| m->event_timer = sd_event_source_unref(m->event_timer); |
| |
| manager_listen_stop(m); |
| |
| m->event_clock_watch = sd_event_source_disable_unref(m->event_clock_watch); |
| |
| m->event_timeout = sd_event_source_unref(m->event_timeout); |
| |
| (void) sd_notify(false, "STATUS=Idle."); |
| } |
| |
| void manager_flush_server_names(Manager *m, ServerType t) { |
| assert(m); |
| |
| if (t == SERVER_SYSTEM) |
| while (m->system_servers) |
| server_name_free(m->system_servers); |
| |
| if (t == SERVER_LINK) |
| while (m->link_servers) |
| server_name_free(m->link_servers); |
| |
| if (t == SERVER_FALLBACK) |
| while (m->fallback_servers) |
| server_name_free(m->fallback_servers); |
| |
| if (t == SERVER_RUNTIME) |
| manager_flush_runtime_servers(m); |
| } |
| |
| void manager_flush_runtime_servers(Manager *m) { |
| assert(m); |
| |
| while (m->runtime_servers) |
| server_name_free(m->runtime_servers); |
| } |
| |
| Manager* manager_free(Manager *m) { |
| if (!m) |
| return NULL; |
| |
| manager_disconnect(m); |
| manager_flush_server_names(m, SERVER_SYSTEM); |
| manager_flush_server_names(m, SERVER_LINK); |
| manager_flush_server_names(m, SERVER_RUNTIME); |
| manager_flush_server_names(m, SERVER_FALLBACK); |
| |
| sd_event_source_unref(m->event_retry); |
| |
| sd_event_source_unref(m->network_event_source); |
| sd_network_monitor_unref(m->network_monitor); |
| |
| sd_event_source_unref(m->event_save_time); |
| |
| sd_resolve_unref(m->resolve); |
| sd_event_unref(m->event); |
| |
| sd_bus_flush_close_unref(m->bus); |
| |
| bus_verify_polkit_async_registry_free(m->polkit_registry); |
| |
| return mfree(m); |
| } |
| |
| static int manager_network_read_link_servers(Manager *m) { |
| _cleanup_strv_free_ char **ntp = NULL; |
| bool changed = false; |
| int r; |
| |
| assert(m); |
| |
| r = sd_network_get_ntp(&ntp); |
| if (r < 0 && r != -ENODATA) { |
| if (r == -ENOMEM) |
| log_oom(); |
| else |
| log_debug_errno(r, "Failed to get link NTP servers: %m"); |
| goto clear; |
| } |
| |
| LIST_FOREACH(names, n, m->link_servers) |
| n->marked = true; |
| |
| STRV_FOREACH(i, ntp) { |
| bool found = false; |
| |
| r = dns_name_is_valid_or_address(*i); |
| if (r < 0) { |
| log_error_errno(r, "Failed to check validity of NTP server name or address '%s': %m", *i); |
| goto clear; |
| } else if (r == 0) { |
| log_error("Invalid NTP server name or address, ignoring: %s", *i); |
| continue; |
| } |
| |
| LIST_FOREACH(names, n, m->link_servers) |
| if (streq(n->string, *i)) { |
| n->marked = false; |
| found = true; |
| break; |
| } |
| |
| if (!found) { |
| r = server_name_new(m, NULL, SERVER_LINK, *i); |
| if (r < 0) { |
| log_oom(); |
| goto clear; |
| } |
| |
| changed = true; |
| } |
| } |
| |
| LIST_FOREACH(names, n, m->link_servers) |
| if (n->marked) { |
| server_name_free(n); |
| changed = true; |
| } |
| |
| return changed; |
| |
| clear: |
| manager_flush_server_names(m, SERVER_LINK); |
| return r; |
| } |
| |
| bool manager_is_connected(Manager *m) { |
| assert(m); |
| |
| /* Return true when the manager is sending a request, resolving a server name, or |
| * in a poll interval. */ |
| return m->server_socket >= 0 || m->resolve_query || m->event_timer; |
| } |
| |
| static int manager_network_event_handler(sd_event_source *s, int fd, uint32_t revents, void *userdata) { |
| Manager *m = ASSERT_PTR(userdata); |
| bool changed, connected, online; |
| int r; |
| |
| sd_network_monitor_flush(m->network_monitor); |
| |
| /* When manager_network_read_link_servers() failed, we assume that the servers are changed. */ |
| changed = manager_network_read_link_servers(m); |
| |
| /* check if the machine is online */ |
| online = network_is_online(); |
| |
| /* check if the client is currently connected */ |
| connected = manager_is_connected(m); |
| |
| if (connected && !online) { |
| log_info("No network connectivity, watching for changes."); |
| manager_disconnect(m); |
| |
| } else if ((!connected || changed) && online) { |
| log_info("Network configuration changed, trying to establish connection."); |
| |
| if (m->current_server_address) |
| r = manager_begin(m); |
| else |
| r = manager_connect(m); |
| if (r < 0) |
| return r; |
| } |
| |
| return 0; |
| } |
| |
| static int manager_network_monitor_listen(Manager *m) { |
| int r, fd, events; |
| |
| assert(m); |
| |
| r = sd_network_monitor_new(&m->network_monitor, NULL); |
| if (r == -ENOENT) { |
| log_info("systemd does not appear to be running, not listening for systemd-networkd events."); |
| return 0; |
| } |
| if (r < 0) |
| return r; |
| |
| fd = sd_network_monitor_get_fd(m->network_monitor); |
| if (fd < 0) |
| return fd; |
| |
| events = sd_network_monitor_get_events(m->network_monitor); |
| if (events < 0) |
| return events; |
| |
| r = sd_event_add_io(m->event, &m->network_event_source, fd, events, manager_network_event_handler, m); |
| if (r < 0) |
| return r; |
| |
| return 0; |
| } |
| |
| int manager_new(Manager **ret) { |
| _cleanup_(manager_freep) Manager *m = NULL; |
| int r; |
| |
| assert(ret); |
| |
| m = new(Manager, 1); |
| if (!m) |
| return -ENOMEM; |
| |
| *m = (Manager) { |
| .root_distance_max_usec = NTP_ROOT_DISTANCE_MAX_USEC, |
| .poll_interval_min_usec = NTP_POLL_INTERVAL_MIN_USEC, |
| .poll_interval_max_usec = NTP_POLL_INTERVAL_MAX_USEC, |
| |
| .connection_retry_usec = DEFAULT_CONNECTION_RETRY_USEC, |
| |
| .server_socket = -EBADF, |
| |
| .ratelimit = (const RateLimit) { |
| RATELIMIT_INTERVAL_USEC, |
| RATELIMIT_BURST |
| }, |
| |
| .save_time_interval_usec = DEFAULT_SAVE_TIME_INTERVAL_USEC, |
| }; |
| |
| r = sd_event_default(&m->event); |
| if (r < 0) |
| return r; |
| |
| (void) sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL); |
| (void) sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL); |
| |
| (void) sd_event_set_watchdog(m->event, true); |
| |
| /* Load previous synchronization state */ |
| r = access("/run/systemd/timesync/synchronized", F_OK); |
| if (r < 0 && errno != ENOENT) |
| log_debug_errno(errno, "Failed to determine whether /run/systemd/timesync/synchronized exists, ignoring: %m"); |
| m->synchronized = r >= 0; |
| |
| r = sd_resolve_default(&m->resolve); |
| if (r < 0) |
| return r; |
| |
| r = sd_resolve_attach_event(m->resolve, m->event, 0); |
| if (r < 0) |
| return r; |
| |
| r = manager_network_monitor_listen(m); |
| if (r < 0) |
| return r; |
| |
| (void) manager_network_read_link_servers(m); |
| |
| *ret = TAKE_PTR(m); |
| |
| return 0; |
| } |
| |
| static int manager_save_time_handler(sd_event_source *s, uint64_t usec, void *userdata) { |
| Manager *m = ASSERT_PTR(userdata); |
| |
| (void) manager_save_time_and_rearm(m, USEC_INFINITY); |
| return 0; |
| } |
| |
| int manager_setup_save_time_event(Manager *m) { |
| int r; |
| |
| assert(m); |
| assert(!m->event_save_time); |
| |
| if (m->save_time_interval_usec == USEC_INFINITY) |
| return 0; |
| |
| /* NB: we'll accumulate scheduling latencies here, but this doesn't matter */ |
| r = sd_event_add_time_relative( |
| m->event, &m->event_save_time, |
| CLOCK_BOOTTIME, |
| m->save_time_interval_usec, |
| 10 * USEC_PER_SEC, |
| manager_save_time_handler, m); |
| if (r < 0) |
| return log_error_errno(r, "Failed to add save time event: %m"); |
| |
| (void) sd_event_source_set_description(m->event_save_time, "save-time"); |
| |
| return 0; |
| } |
| |
| static int manager_save_time_and_rearm(Manager *m, usec_t t) { |
| int r; |
| |
| assert(m); |
| |
| /* Updates the timestamp file to the specified time. If 't' is USEC_INFINITY uses the current system |
| * clock, but otherwise uses the specified timestamp. Note that whenever we acquire an NTP sync the |
| * specified timestamp value might be more accurate than the system clock, since the latter is |
| * subject to slow adjustments. */ |
| r = touch_file(CLOCK_FILE, false, t, UID_INVALID, GID_INVALID, MODE_INVALID); |
| if (r < 0) |
| log_debug_errno(r, "Failed to update " CLOCK_FILE ", ignoring: %m"); |
| |
| m->save_on_exit = true; |
| |
| if (m->save_time_interval_usec != USEC_INFINITY) { |
| r = sd_event_source_set_time_relative(m->event_save_time, m->save_time_interval_usec); |
| if (r < 0) |
| return log_error_errno(r, "Failed to rearm save time event: %m"); |
| |
| r = sd_event_source_set_enabled(m->event_save_time, SD_EVENT_ONESHOT); |
| if (r < 0) |
| return log_error_errno(r, "Failed to enable save time event: %m"); |
| } |
| |
| return 0; |
| } |
