+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- 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 <stdlib.h>
-#include <errno.h>
-#include <time.h>
-#include <math.h>
-#include <netinet/in.h>
-#include <netinet/ip.h>
-#include <sys/timerfd.h>
-#include <sys/timex.h>
-#include <sys/socket.h>
-#include <resolv.h>
-#include <sys/types.h>
-
-#include "missing.h"
-#include "util.h"
-#include "sparse-endian.h"
-#include "log.h"
-#include "socket-util.h"
-#include "list.h"
-#include "ratelimit.h"
-#include "strv.h"
-#include "sd-daemon.h"
-#include "network-util.h"
-#include "timesyncd-conf.h"
-#include "timesyncd-manager.h"
-#include "time-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
-
-/*
- * "A client MUST NOT under any conditions use a poll interval less
- * than 15 seconds."
- */
-#define NTP_POLL_INTERVAL_MIN_SEC 32
-#define NTP_POLL_INTERVAL_MAX_SEC 2048
-
-/*
- * Maximum delta in seconds which the system clock is gradually adjusted
- * (slew) 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))
-
-/* Maximum acceptable root distance in seconds. */
-#define NTP_MAX_ROOT_DISTANCE 5.0
-
-/* 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 < NTP_POLL_INTERVAL_MAX_SEC * USEC_PER_SEC)
- m->retry_interval *= 2;
- } else
- m->retry_interval = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
-
- 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_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;
-
- /* 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 r;
-
- touch("/var/lib/systemd/clock");
-
- m->drift_ppm = tmx.freq / 65536;
-
- log_debug(" status : %04i %s\n"
- " time now : %li.%03llu\n"
- " constant : %li\n"
- " offset : %+.3f sec\n"
- " freq offset : %+li (%i ppm)\n",
- tmx.status, tmx.status & STA_UNSYNC ? "unsync" : "sync",
- tmx.time.tv_sec, (unsigned long long) (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 = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
- m->poll_resync = false;
- return;
- }
-
- /* set to minimal poll interval */
- if (!spike && fabs(offset) > NTP_ACCURACY_SEC) {
- m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
- return;
- }
-
- /* increase polling interval */
- if (fabs(offset) < NTP_ACCURACY_SEC * 0.25) {
- if (m->poll_interval_usec < NTP_POLL_INTERVAL_MAX_SEC * USEC_PER_SEC)
- m->poll_interval_usec *= 2;
- return;
- }
-
- /* decrease polling interval */
- if (spike || fabs(offset) > NTP_ACCURACY_SEC * 0.75) {
- if (m->poll_interval_usec > NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC)
- 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;
- for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
- 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) != 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 > NTP_MAX_ROOT_DISTANCE) {
- 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(errno, "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)" : "");
-
- 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->missed_replies = NTP_MAX_MISSED_REPLIES;
- if (m->poll_interval_usec == 0)
- m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
-
- server_address_pretty(m->current_server_address, &pretty);
- log_debug("Using NTP server %s (%s).", strna(pretty), m->current_server_name->string);
- sd_notifyf(false, "STATUS=Using 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 < NTP_POLL_INTERVAL_MAX_SEC * USEC_PER_SEC)
- 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 < 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->server_socket = m->clock_watch_fd = -1;
-
- RATELIMIT_INIT(m->ratelimit, RATELIMIT_INTERVAL_USEC, RATELIMIT_BURST);
-
- r = manager_parse_server_string(m, SERVER_FALLBACK, NTP_SERVERS);
- if (r < 0)
- return r;
-
- 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;
-}
~ianmdlvl / elogind.git / commitdiff