| /* SPDX-License-Identifier: LGPL-2.1+ */ |
| /*** |
| This file is part of systemd. |
| |
| Copyright 2014 Kay Sievers, Lennart Poettering |
| |
| systemd is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, or |
| (at your option) any later version. |
| |
| systemd is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with systemd; If not, see <http://www.gnu.org/licenses/>. |
| ***/ |
| |
| #include <errno.h> |
| #include <math.h> |
| #include <netinet/in.h> |
| #include <netinet/ip.h> |
| #include <resolv.h> |
| #include <stdlib.h> |
| #include <sys/socket.h> |
| #include <sys/timerfd.h> |
| #include <sys/timex.h> |
| #include <sys/types.h> |
| #include <time.h> |
| |
| #include "sd-daemon.h" |
| |
| #include "alloc-util.h" |
| #include "fd-util.h" |
| #include "fs-util.h" |
| #include "list.h" |
| #include "log.h" |
| #include "missing.h" |
| #include "network-util.h" |
| #include "ratelimit.h" |
| #include "socket-util.h" |
| #include "sparse-endian.h" |
| #include "string-util.h" |
| #include "strv.h" |
| #include "time-util.h" |
| #include "timesyncd-conf.h" |
| #include "timesyncd-manager.h" |
| #include "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 |
| |
| /* NTP protocol, packet header */ |
| #define NTP_LEAP_PLUSSEC 1 |
| #define NTP_LEAP_MINUSSEC 2 |
| #define NTP_LEAP_NOTINSYNC 3 |
| #define NTP_MODE_CLIENT 3 |
| #define NTP_MODE_SERVER 4 |
| #define NTP_FIELD_LEAP(f) (((f) >> 6) & 3) |
| #define NTP_FIELD_VERSION(f) (((f) >> 3) & 7) |
| #define NTP_FIELD_MODE(f) ((f) & 7) |
| #define NTP_FIELD(l, v, m) (((l) << 6) | ((v) << 3) | (m)) |
| |
| /* Default of maximum acceptable root distance in microseconds. */ |
| #define NTP_MAX_ROOT_DISTANCE (5 * USEC_PER_SEC) |
| |
| /* Maximum number of missed replies before selecting another source. */ |
| #define NTP_MAX_MISSED_REPLIES 2 |
| |
| /* |
| * "NTP timestamps are represented as a 64-bit unsigned fixed-point number, |
| * in seconds relative to 0h on 1 January 1900." |
| */ |
| #define OFFSET_1900_1970 UINT64_C(2208988800) |
| |
| #define RETRY_USEC (30*USEC_PER_SEC) |
| #define RATELIMIT_INTERVAL_USEC (10*USEC_PER_SEC) |
| #define RATELIMIT_BURST 10 |
| |
| #define TIMEOUT_USEC (10*USEC_PER_SEC) |
| |
| struct ntp_ts { |
| be32_t sec; |
| be32_t frac; |
| } _packed_; |
| |
| struct ntp_ts_short { |
| be16_t sec; |
| be16_t frac; |
| } _packed_; |
| |
| struct ntp_msg { |
| uint8_t field; |
| uint8_t stratum; |
| int8_t poll; |
| int8_t precision; |
| struct ntp_ts_short root_delay; |
| struct ntp_ts_short root_dispersion; |
| char refid[4]; |
| struct ntp_ts reference_time; |
| struct ntp_ts origin_time; |
| struct ntp_ts recv_time; |
| struct ntp_ts trans_time; |
| } _packed_; |
| |
| 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 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 int manager_timeout(sd_event_source *source, usec_t usec, void *userdata) { |
| _cleanup_free_ char *pretty = NULL; |
| Manager *m = userdata; |
| |
| assert(m); |
| 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) |
| return log_warning_errno(r, "Failed to setup connection socket: %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_or_monotonic(), &m->trans_time_mon) >= 0); |
| assert_se(clock_gettime(CLOCK_REALTIME, &m->trans_time) >= 0); |
| ntpmsg.trans_time.sec = htobe32(m->trans_time.tv_sec + OFFSET_1900_1970); |
| 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) { |
| if (m->retry_interval < m->poll_interval_max_usec) |
| m->retry_interval *= 2; |
| } else |
| m->retry_interval = m->poll_interval_min_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_or_monotonic(), |
| now(clock_boottime_or_monotonic()) + 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 = userdata; |
| |
| assert(m); |
| |
| 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(m->event_timer, now(clock_boottime_or_monotonic()) + next); |
| if (r < 0) |
| return r; |
| |
| return sd_event_source_set_enabled(m->event_timer, SD_EVENT_ONESHOT); |
| } |
| |
| return sd_event_add_time( |
| m->event, |
| &m->event_timer, |
| clock_boottime_or_monotonic(), |
| now(clock_boottime_or_monotonic()) + next, 0, |
| manager_timer, m); |
| } |
| |
| static int manager_clock_watch(sd_event_source *source, int fd, uint32_t revents, void *userdata) { |
| Manager *m = userdata; |
| |
| assert(m); |
| |
| /* 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) { |
| |
| struct itimerspec its = { |
| .it_value.tv_sec = TIME_T_MAX |
| }; |
| |
| int r; |
| |
| assert(m); |
| |
| m->event_clock_watch = sd_event_source_unref(m->event_clock_watch); |
| safe_close(m->clock_watch_fd); |
| |
| m->clock_watch_fd = timerfd_create(CLOCK_REALTIME, TFD_NONBLOCK|TFD_CLOEXEC); |
| if (m->clock_watch_fd < 0) |
| return log_error_errno(errno, "Failed to create timerfd: %m"); |
| |
| if (timerfd_settime(m->clock_watch_fd, TFD_TIMER_ABSTIME|TFD_TIMER_CANCEL_ON_SET, &its, NULL) < 0) |
| return log_error_errno(errno, "Failed to set up timerfd: %m"); |
| |
| r = sd_event_add_io(m->event, &m->event_clock_watch, m->clock_watch_fd, EPOLLIN, 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 = {}; |
| int r; |
| |
| 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.modes = ADJ_STATUS | ADJ_NANO | ADJ_OFFSET | ADJ_TIMECONST | ADJ_MAXERROR | ADJ_ESTERROR; |
| tmx.status = STA_PLL; |
| tmx.offset = offset * NSEC_PER_SEC; |
| tmx.constant = log2i(m->poll_interval_usec / USEC_PER_SEC) - 4; |
| tmx.maxerror = 0; |
| tmx.esterror = 0; |
| log_debug(" adjust (slew): %+.3f sec", offset); |
| } else { |
| tmx.modes = ADJ_STATUS | ADJ_NANO | ADJ_SETOFFSET | ADJ_MAXERROR | ADJ_ESTERROR; |
| |
| /* ADJ_NANO uses nanoseconds in the microseconds field */ |
| tmx.time.tv_sec = (long)offset; |
| tmx.time.tv_usec = (offset - tmx.time.tv_sec) * NSEC_PER_SEC; |
| tmx.maxerror = 0; |
| tmx.esterror = 0; |
| |
| /* 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; |
| } |
| |
| r = clock_adjtime(CLOCK_REALTIME, &tmx); |
| if (r < 0) |
| return -errno; |
| |
| /* If touch fails, there isn't much we can do. Maybe it'll work next time. */ |
| (void) touch("/var/lib/systemd/timesync/clock"); |
| |
| m->drift_ppm = tmx.freq / 65536; |
| |
| 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" (%i 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, m->drift_ppm); |
| |
| return 0; |
| } |
| |
| static bool manager_sample_spike_detection(Manager *m, double offset, double delay) { |
| unsigned int 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 = userdata; |
| struct ntp_msg ntpmsg; |
| |
| struct iovec iov = { |
| .iov_base = &ntpmsg, |
| .iov_len = sizeof(ntpmsg), |
| }; |
| union { |
| struct cmsghdr cmsghdr; |
| uint8_t buf[CMSG_SPACE(sizeof(struct timeval))]; |
| } 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 cmsghdr *cmsg; |
| struct timespec *recv_time; |
| ssize_t len; |
| double origin, receive, trans, dest; |
| double delay, offset; |
| double root_distance; |
| bool spike; |
| int leap_sec; |
| int r; |
| |
| assert(source); |
| assert(m); |
| |
| if (revents & (EPOLLHUP|EPOLLERR)) { |
| log_warning("Server connection returned error."); |
| return manager_connect(m); |
| } |
| |
| len = recvmsg(fd, &msghdr, MSG_DONTWAIT); |
| if (len < 0) { |
| if (errno == EAGAIN) |
| return 0; |
| |
| log_warning("Error receiving message. Disconnecting."); |
| 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 = NULL; |
| CMSG_FOREACH(cmsg, &msghdr) { |
| if (cmsg->cmsg_level != SOL_SOCKET) |
| continue; |
| |
| switch (cmsg->cmsg_type) { |
| case SCM_TIMESTAMPNS: |
| recv_time = (struct timespec *) CMSG_DATA(cmsg); |
| break; |
| } |
| } |
| if (!recv_time) { |
| log_error("Invalid packet timestamp."); |
| return -EINVAL; |
| } |
| |
| 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) != m->trans_time.tv_sec + OFFSET_1900_1970 || |
| 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->max_root_distance_usec / (double) USEC_PER_SEC) { |
| log_debug("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 : %u\n" |
| " version : %u\n" |
| " mode : %u\n" |
| " stratum : %u\n" |
| " precision : %.6f sec (%d)\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); |
| |
| if (!spike) { |
| m->sync = true; |
| r = manager_adjust_clock(m, offset, leap_sec); |
| if (r < 0) |
| log_error_errno(r, "Failed to call clock_adjtime(): %m"); |
| } |
| |
| log_debug("interval/delta/delay/jitter/drift " USEC_FMT "s/%+.3fs/%.3fs/%.3fs/%+ippm%s", |
| m->poll_interval_usec / USEC_PER_SEC, offset, delay, m->samples_jitter, m->drift_ppm, |
| spike ? " (ignored)" : ""); |
| |
| if (!m->good) { |
| _cleanup_free_ char *pretty = NULL; |
| |
| m->good = true; |
| |
| server_address_pretty(m->current_server_address, &pretty); |
| log_info("Synchronized to time server %s (%s).", strna(pretty), m->current_server_name->string); |
| sd_notifyf(false, "STATUS=Synchronized to time server %s (%s).", strna(pretty), m->current_server_name->string); |
| } |
| |
| 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 = {}; |
| static const int tos = IPTOS_LOWDELAY; |
| static const int on = 1; |
| 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(m->server_socket, SOL_SOCKET, SO_TIMESTAMPNS, &on, sizeof(on)); |
| if (r < 0) |
| return -errno; |
| |
| (void) setsockopt(m->server_socket, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)); |
| |
| 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->good = 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); |
| 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, void *userdata) { |
| Manager *m = userdata; |
| 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_warning("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 = userdata; |
| |
| assert(m); |
| |
| 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_test(&m->ratelimit)) { |
| log_debug("Slowing down attempts to contact servers."); |
| |
| 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); |
| 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 { |
| struct addrinfo hints = { |
| .ai_flags = AI_NUMERICSERV|AI_ADDRCONFIG, |
| .ai_socktype = SOCK_DGRAM, |
| }; |
| |
| /* 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 system list, then the link list. |
| * After having processed the link list we |
| * jump back to the system list. However, if |
| * both lists are empty, we change to the |
| * fallback list. */ |
| if (!m->current_server_name || m->current_server_name->type == SERVER_LINK) { |
| f = m->system_servers; |
| if (!f) |
| f = m->link_servers; |
| } else { |
| f = m->link_servers; |
| if (!f) |
| f = m->system_servers; |
| else |
| restart = false; |
| } |
| |
| 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) { |
| log_debug("Waiting after exhausting servers."); |
| 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); |
| 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); |
| |
| r = sd_resolve_getaddrinfo(m->resolve, &m->resolve_query, m->current_server_name->string, "123", &hints, manager_resolve_handler, 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_unref(m->event_clock_watch); |
| m->clock_watch_fd = safe_close(m->clock_watch_fd); |
| |
| m->event_timeout = sd_event_source_unref(m->event_timeout); |
| |
| sd_notifyf(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); |
| } |
| |
| void manager_free(Manager *m) { |
| if (!m) |
| return; |
| |
| manager_disconnect(m); |
| manager_flush_server_names(m, SERVER_SYSTEM); |
| manager_flush_server_names(m, SERVER_LINK); |
| 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_resolve_unref(m->resolve); |
| sd_event_unref(m->event); |
| |
| free(m); |
| } |
| |
| static int manager_network_read_link_servers(Manager *m) { |
| _cleanup_strv_free_ char **ntp = NULL; |
| ServerName *n, *nx; |
| char **i; |
| int r; |
| |
| assert(m); |
| |
| r = sd_network_get_ntp(&ntp); |
| if (r < 0) |
| goto clear; |
| |
| LIST_FOREACH(names, n, m->link_servers) |
| n->marked = true; |
| |
| STRV_FOREACH(i, ntp) { |
| bool found = false; |
| |
| 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) |
| goto clear; |
| } |
| } |
| |
| LIST_FOREACH_SAFE(names, n, nx, m->link_servers) |
| if (n->marked) |
| server_name_free(n); |
| |
| return 0; |
| |
| clear: |
| manager_flush_server_names(m, SERVER_LINK); |
| return r; |
| } |
| |
| static int manager_network_event_handler(sd_event_source *s, int fd, uint32_t revents, void *userdata) { |
| Manager *m = userdata; |
| bool connected, online; |
| int r; |
| |
| assert(m); |
| |
| sd_network_monitor_flush(m->network_monitor); |
| |
| manager_network_read_link_servers(m); |
| |
| /* check if the machine is online */ |
| online = network_is_online(); |
| |
| /* check if the client is currently connected */ |
| connected = m->server_socket >= 0 || m->resolve_query || m->exhausted_servers; |
| |
| if (connected && !online) { |
| log_info("No network connectivity, watching for changes."); |
| manager_disconnect(m); |
| |
| } else if (!connected && 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 = new0(Manager, 1); |
| if (!m) |
| return -ENOMEM; |
| |
| m->max_root_distance_usec = NTP_MAX_ROOT_DISTANCE; |
| m->poll_interval_min_usec = NTP_POLL_INTERVAL_MIN_USEC; |
| m->poll_interval_max_usec = NTP_POLL_INTERVAL_MAX_USEC; |
| |
| m->server_socket = m->clock_watch_fd = -1; |
| |
| RATELIMIT_INIT(m->ratelimit, RATELIMIT_INTERVAL_USEC, RATELIMIT_BURST); |
| |
| r = sd_event_default(&m->event); |
| if (r < 0) |
| return r; |
| |
| sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL); |
| sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL); |
| |
| sd_event_set_watchdog(m->event, true); |
| |
| 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; |
| |
| manager_network_read_link_servers(m); |
| |
| *ret = m; |
| m = NULL; |
| |
| return 0; |
| } |