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-rw-r--r--src/systemd-timesync/timesyncd.c164
1 files changed, 164 insertions, 0 deletions
diff --git a/src/systemd-timesync/timesyncd.c b/src/systemd-timesync/timesyncd.c
new file mode 100644
index 0000000000..388eefac48
--- /dev/null
+++ b/src/systemd-timesync/timesyncd.c
@@ -0,0 +1,164 @@
+/***
+ 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 <systemd/sd-daemon.h>
+#include <systemd/sd-event.h>
+
+#include "capability-util.h"
+#include "clock-util.h"
+#include "fd-util.h"
+#include "fs-util.h"
+#include "network-util.h"
+#include "signal-util.h"
+#include "timesyncd-conf.h"
+#include "timesyncd-manager.h"
+#include "user-util.h"
+
+static int load_clock_timestamp(uid_t uid, gid_t gid) {
+ _cleanup_close_ int fd = -1;
+ usec_t min = TIME_EPOCH * USEC_PER_SEC;
+ usec_t ct;
+ int r;
+
+ /* Let's try to make sure that the clock is always
+ * monotonically increasing, by saving the clock whenever we
+ * have a new NTP time, or when we shut down, and restoring it
+ * when we start again. This is particularly helpful on
+ * systems lacking a battery backed RTC. We also will adjust
+ * the time to at least the build time of systemd. */
+
+ fd = open("/var/lib/systemd/clock", O_RDWR|O_CLOEXEC, 0644);
+ if (fd >= 0) {
+ struct stat st;
+ usec_t stamp;
+
+ /* check if the recorded time is later than the compiled-in one */
+ r = fstat(fd, &st);
+ if (r >= 0) {
+ stamp = timespec_load(&st.st_mtim);
+ if (stamp > min)
+ min = stamp;
+ }
+
+ /* Try to fix the access mode, so that we can still
+ touch the file after dropping priviliges */
+ (void) fchmod(fd, 0644);
+ (void) fchown(fd, uid, gid);
+
+ } else
+ /* create stamp file with the compiled-in date */
+ (void) touch_file("/var/lib/systemd/clock", true, min, uid, gid, 0644);
+
+ ct = now(CLOCK_REALTIME);
+ if (ct < min) {
+ struct timespec ts;
+ char date[FORMAT_TIMESTAMP_MAX];
+
+ log_info("System clock time unset or jumped backwards, restoring from recorded timestamp: %s",
+ format_timestamp(date, sizeof(date), min));
+
+ if (clock_settime(CLOCK_REALTIME, timespec_store(&ts, min)) < 0)
+ log_error_errno(errno, "Failed to restore system clock: %m");
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[]) {
+ _cleanup_(manager_freep) Manager *m = NULL;
+ const char *user = "systemd-timesync";
+ uid_t uid;
+ gid_t gid;
+ int r;
+
+ log_set_target(LOG_TARGET_AUTO);
+ log_set_facility(LOG_CRON);
+ log_parse_environment();
+ log_open();
+
+ umask(0022);
+
+ if (argc != 1) {
+ log_error("This program does not take arguments.");
+ r = -EINVAL;
+ goto finish;
+ }
+
+ r = get_user_creds(&user, &uid, &gid, NULL, NULL);
+ if (r < 0) {
+ log_error_errno(r, "Cannot resolve user name %s: %m", user);
+ goto finish;
+ }
+
+ r = load_clock_timestamp(uid, gid);
+ if (r < 0)
+ goto finish;
+
+ r = drop_privileges(uid, gid, (1ULL << CAP_SYS_TIME));
+ if (r < 0)
+ goto finish;
+
+ assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, SIGINT, -1) >= 0);
+
+ r = manager_new(&m);
+ if (r < 0) {
+ log_error_errno(r, "Failed to allocate manager: %m");
+ goto finish;
+ }
+
+ if (clock_is_localtime() > 0) {
+ log_info("The system is configured to read the RTC time in the local time zone. "
+ "This mode can not be fully supported. All system time to RTC updates are disabled.");
+ m->rtc_local_time = true;
+ }
+
+ r = manager_parse_config_file(m);
+ if (r < 0)
+ log_warning_errno(r, "Failed to parse configuration file: %m");
+
+ log_debug("systemd-timesyncd running as pid " PID_FMT, getpid());
+ sd_notify(false,
+ "READY=1\n"
+ "STATUS=Daemon is running");
+
+ if (network_is_online()) {
+ r = manager_connect(m);
+ if (r < 0)
+ goto finish;
+ }
+
+ r = sd_event_loop(m->event);
+ if (r < 0) {
+ log_error_errno(r, "Failed to run event loop: %m");
+ goto finish;
+ }
+
+ /* if we got an authoritative time, store it in the file system */
+ if (m->sync)
+ (void) touch("/var/lib/systemd/clock");
+
+ sd_event_get_exit_code(m->event, &r);
+
+finish:
+ sd_notify(false,
+ "STOPPING=1\n"
+ "STATUS=Shutting down...");
+
+ return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}