/***
This file is part of systemd.
- Copyright 2014 Kay Sievers
+ 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
#include <sys/timex.h>
#include <sys/socket.h>
#include <resolv.h>
+#include <sys/prctl.h>
+#include <sys/types.h>
+#include <grp.h>
#include "missing.h"
#include "util.h"
#include "list.h"
#include "ratelimit.h"
#include "strv.h"
+#include "conf-parser.h"
#include "sd-event.h"
#include "sd-resolve.h"
#include "sd-daemon.h"
+#include "sd-network.h"
+#include "event-util.h"
+#include "network-util.h"
+#include "capability.h"
+#include "timesyncd.h"
#define TIME_T_MAX (time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
#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;
struct ntp_ts trans_time;
} _packed_;
-typedef struct Manager Manager;
-typedef struct ServerAddress ServerAddress;
-typedef struct ServerName ServerName;
-
-struct ServerAddress {
- union sockaddr_union sockaddr;
- socklen_t socklen;
- LIST_FIELDS(ServerAddress, addresses);
-};
-
-struct ServerName {
- char *string;
- LIST_HEAD(ServerAddress, addresses);
- LIST_FIELDS(ServerName, names);
-};
-
-struct Manager {
- sd_event *event;
- sd_resolve *resolve;
-
- LIST_HEAD(ServerName, servers);
-
- RateLimit ratelimit;
-
- /* peer */
- sd_resolve_query *resolve_query;
- sd_event_source *event_receive;
- ServerName *current_server_name;
- ServerAddress *current_server_address;
- int server_socket;
- uint64_t packet_count;
-
- /* last sent packet */
- struct timespec trans_time_mon;
- struct timespec trans_time;
- usec_t retry_interval;
- bool pending;
-
- /* poll timer */
- sd_event_source *event_timer;
- usec_t poll_interval_usec;
- bool poll_resync;
-
- /* history data */
- struct {
- double offset;
- double delay;
- } samples[8];
- unsigned int samples_idx;
- double samples_jitter;
-
- /* last change */
- bool jumped;
- int drift_ppm;
-
- /* watch for time changes */
- sd_event_source *event_clock_watch;
- int clock_watch_fd;
-
- /* Retry connections */
- sd_event_source *event_retry;
-
- /* Handle SIGINT/SIGTERM */
- sd_event_source *sigterm, *sigint;
-};
-
static void manager_free(Manager *m);
DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_free);
#define _cleanup_manager_free_ _cleanup_(manager_freep)
return d * d;
}
+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);
+
+ sockaddr_pretty(&m->current_server_address->sockaddr.sa, m->current_server_address->socklen, true, &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 = {
assert(m->current_server_name);
assert(m->current_server_address);
+ m->event_timeout = sd_event_source_unref(m->event_timeout);
+
/*
* Set transmit timestamp, remember it; the server will send that back
* as the origin timestamp and we have an indication that this is the
ntpmsg.trans_time.sec = htobe32(m->trans_time.tv_sec + OFFSET_1900_1970);
ntpmsg.trans_time.frac = htobe32(m->trans_time.tv_nsec);
- r = sockaddr_pretty(&m->current_server_address->sockaddr.sa, m->current_server_address->socklen, true, &pretty);
- if (r < 0) {
- log_error("Failed to format sockaddr: %s", strerror(-r));
- return r;
- }
+ sockaddr_pretty(&m->current_server_address->sockaddr.sa, m->current_server_address->socklen, true, &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)", pretty, m->current_server_name->string);
+ log_debug("Sent NTP request to %s (%s).", strna(pretty), m->current_server_name->string);
} else {
- log_debug("Sending NTP request to %s (%s) failed: %m", pretty, m->current_server_name->string);
+ log_debug("Sending NTP request to %s (%s) failed: %m", strna(pretty), m->current_server_name->string);
return manager_connect(m);
}
- /* re-arm timer with incresing timeout, in case the packets never arrive back */
+ /* 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;
return r;
}
+ r = sd_event_add_time(
+ m->event,
+ &m->event_timeout,
+ CLOCK_MONOTONIC,
+ now(CLOCK_MONOTONIC) + TIMEOUT_USEC, 0,
+ manager_timeout, m);
+ if (r < 0) {
+ log_error("Failed to arm timeout timer: %s", strerror(-r));
+ return r;
+ }
+
return 0;
}
}
static int manager_receive_response(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
- _cleanup_free_ char *pretty = NULL;
Manager *m = userdata;
struct ntp_msg ntpmsg;
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) {
log_debug("Server is not synchronized. Disconnecting.");
return manager_connect(m);
}
- if (NTP_FIELD_VERSION(ntpmsg.field) != 4 && NTP_FIELD_VERSION(ntpmsg.field) != 3) {
+ 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);
}
log_error("Failed to call clock_adjtime(): %m");
}
- r = sockaddr_pretty(&m->current_server_address->sockaddr.sa, m->current_server_address->socklen, true, &pretty);
- if (r < 0) {
- log_error("Failed to format socket address: %s", strerror(-r));
- return r;
- }
-
- log_info("%s (%s): interval/delta/delay/jitter/drift %llus/%+.3fs/%.3fs/%.3fs/%+ippm%s",
- pretty, m->current_server_name->string, m->poll_interval_usec / USEC_PER_SEC, offset, delay, m->samples_jitter, m->drift_ppm,
+ log_info("interval/delta/delay/jitter/drift %llus/%+.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);
m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
- r = sockaddr_pretty(&m->current_server_address->sockaddr.sa, m->current_server_address->socklen, true, &pretty);
- if (r < 0) {
- log_warning("Failed to decode address of %s: %s", m->current_server_name->string, strerror(-r));
- return r;
- }
-
- log_debug("Connecting to NTP server %s (%s).", pretty, m->current_server_name->string);
- sd_notifyf(false, "STATUS=Using Time Server %s (%s)", pretty, m->current_server_name->string);
+ sockaddr_pretty(&m->current_server_address->sockaddr.sa, m->current_server_address->socklen, true, &pretty);
+ log_info("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_listen_setup(m);
if (r < 0) {
m->resolve_query = sd_resolve_query_unref(m->resolve_query);
if (ret != 0) {
- log_error("Failed to resolve %s: %s", m->current_server_name->string, gai_strerror(ret));
+ log_info("Failed to resolve %s: %s", m->current_server_name->string, gai_strerror(ret));
/* Try next host */
return manager_connect(m);
last = a;
sockaddr_pretty(&a->sockaddr.sa, a->socklen, true, &pretty);
- log_debug("Found address %s for %s.", pretty, m->current_server_name->string);
+ log_debug("Resolved address %s for %s.", pretty, m->current_server_name->string);
}
if (!m->current_server_name->addresses) {
return 0;
}
+static int manager_add_server_string(Manager *m, const char *string) {
+ char *w, *state;
+ size_t l;
+ int r;
+
+ assert(m);
+ assert(string);
+
+ FOREACH_WORD_QUOTED(w, l, string, state) {
+ char t[l+1];
+
+ memcpy(t, w, l);
+ t[l] = 0;
+
+ r = manager_add_server(m, t);
+ if (r < 0)
+ log_error("Failed to add server %s to configuration, ignoring: %s", t, strerror(-r));
+ }
+
+ return 0;
+}
+
static void manager_disconnect(Manager *m) {
assert(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.");
}
static int manager_new(Manager **ret) {
if (r < 0)
return r;
- sd_event_add_signal(m->event, &m->sigterm, SIGTERM, NULL, NULL);
- sd_event_add_signal(m->event, &m->sigint, SIGINT, NULL, NULL);
+ sd_event_set_watchdog(m->event, true);
+
+ sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
+ sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
r = sd_resolve_default(&m->resolve);
if (r < 0)
r = sd_resolve_attach_event(m->resolve, m->event, 0);
if (r < 0)
- return 0;
+ return r;
r = manager_clock_watch_setup(m);
if (r < 0)
manager_disconnect(m);
manager_flush_names(m);
- sd_event_source_unref(m->sigint);
- sd_event_source_unref(m->sigterm);
-
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);
}
+int config_parse_servers(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Manager *m = userdata;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+
+ manager_flush_names(m);
+ manager_add_server_string(m, rvalue);
+
+ return 0;
+}
+
+static int manager_parse_config_file(Manager *m) {
+ static const char fn[] = "/etc/systemd/timesyncd.conf";
+ _cleanup_fclose_ FILE *f = NULL;
+ int r;
+
+ assert(m);
+
+ f = fopen(fn, "re");
+ if (!f) {
+ if (errno == ENOENT)
+ return 0;
+
+ log_warning("Failed to open configuration file %s: %m", fn);
+ return -errno;
+ }
+
+ r = config_parse(NULL, fn, f, "Time\0", config_item_perf_lookup,
+ (void*) timesyncd_gperf_lookup, false, false, m);
+ if (r < 0)
+ log_warning("Failed to parse configuration file: %s", strerror(-r));
+
+ return r;
+}
+
+static bool network_is_online(void) {
+ _cleanup_free_ char *state = NULL;
+ int r;
+
+ r = sd_network_get_operational_state(&state);
+ if (r >= 0 && streq("carrier", state))
+ return true;
+ else
+ return false;
+}
+
+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);
+
+ /* check if the machine is online */
+ online = network_is_online();
+
+ /* check if the client is currently connected */
+ connected = (m->server_socket != -1);
+
+ if (connected && !online) {
+ log_info("No network connectivity. Suspending.");
+ manager_disconnect(m);
+ } else if (!connected && online) {
+ log_info("Network connectivity detected. Resuming.");
+ if (m->current_server_address) {
+ r = manager_begin(m);
+ if (r < 0)
+ return r;
+ } else {
+ r = manager_connect(m);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ sd_network_monitor_flush(m->network_monitor);
+
+ return 0;
+}
+
+static int manager_network_monitor_listen(Manager *m) {
+ _cleanup_event_source_unref_ sd_event_source *event_source = NULL;
+ _cleanup_network_monitor_unref_ sd_network_monitor *monitor = NULL;
+ int r, fd, events;
+
+ r = sd_network_monitor_new(NULL, &monitor);
+ if (r < 0)
+ return r;
+
+ fd = sd_network_monitor_get_fd(monitor);
+ if (fd < 0)
+ return fd;
+
+ events = sd_network_monitor_get_events(monitor);
+ if (events < 0)
+ return events;
+
+ r = sd_event_add_io(m->event, &event_source, fd, events,
+ &manager_network_event_handler, m);
+ if (r < 0)
+ return r;
+
+ m->network_monitor = monitor;
+ m->network_event_source = event_source;
+ monitor = NULL;
+ event_source = NULL;
+
+ return 0;
+}
+
+static int drop_priviliges(void) {
+ static const cap_value_t bits[] = {
+ CAP_SYS_TIME,
+ };
+
+ _cleanup_cap_free_ cap_t d = NULL;
+ const char *name = "systemd-timesync";
+ uid_t uid;
+ gid_t gid;
+ int r;
+
+ /* Unfortunately we cannot leave privilige dropping to PID 1
+ * here, since we want to run as user but want to keep te
+ * CAP_SYS_TIME capability. Since file capabilities have been
+ * introduced this cannot be done across exec() anymore,
+ * unless our binary has the capability configured in the file
+ * system, which we want to avoid. */
+
+ r = get_user_creds(&name, &uid, &gid, NULL, NULL);
+ if (r < 0) {
+ log_error("Cannot resolve user name %s: %s", name, strerror(-r));
+ return r;
+ }
+
+ if (setresgid(gid, gid, gid) < 0) {
+ log_error("Failed change group ID: %m");
+ return -errno;
+ }
+
+ if (setgroups(0, NULL) < 0) {
+ log_error("Failed to drop auxiliary groups list: %m");
+ return -errno;
+ }
+
+ if (prctl(PR_SET_KEEPCAPS, 1) < 0) {
+ log_error("Failed to enable keep capabilities flag: %m");
+ return -errno;
+ }
+
+ r = setresuid(uid, uid, uid);
+ if (r < 0) {
+ log_error("Failed change user ID: %m");
+ return -errno;
+ }
+
+ if (prctl(PR_SET_KEEPCAPS, 0) < 0) {
+ log_error("Failed to disable keep capabilities flag: %m");
+ return -errno;
+ }
+
+ r = capability_bounding_set_drop(~(1ULL << CAP_SYS_TIME), true);
+ if (r < 0) {
+ log_error("Failed to drop capabilities: %s", strerror(-r));
+ return r;
+ }
+
+ d = cap_init();
+ if (!d)
+ return log_oom();
+
+ if (cap_set_flag(d, CAP_EFFECTIVE, ELEMENTSOF(bits), bits, CAP_SET) < 0 ||
+ cap_set_flag(d, CAP_PERMITTED, ELEMENTSOF(bits), bits, CAP_SET) < 0) {
+ log_error("Failed to enable capabilities bits: %m");
+ return -errno;
+ }
+
+ if (cap_set_proc(d) < 0) {
+ log_error("Failed to increase capabilities: %m");
+ return -errno;
+ }
+
+ return 0;
+}
+
int main(int argc, char *argv[]) {
_cleanup_manager_free_ Manager *m = NULL;
- const char *x;
int r;
+ if (argc > 1) {
+ log_error("This program does not take arguments.");
+ return EXIT_FAILURE;
+ }
+
log_set_target(LOG_TARGET_AUTO);
+ log_set_facility(LOG_CRON);
log_parse_environment();
log_open();
+ umask(0022);
+
+ r = drop_priviliges();
+ if (r < 0)
+ goto out;
+
assert_se(sigprocmask_many(SIG_BLOCK, SIGTERM, SIGINT, -1) == 0);
r = manager_new(&m);
goto out;
}
+ manager_add_server_string(m, NTP_SERVERS);
+ manager_parse_config_file(m);
+
+ r = manager_network_monitor_listen(m);
+ if (r < 0) {
+ log_error("Failed to listen to networkd events: %s", strerror(-r));
+ goto out;
+ }
+
+ log_debug("systemd-timesyncd running as pid %lu", (unsigned long) getpid());
sd_notify(false, "READY=1");
- FOREACH_STRING(x, "time1.google.com", "time2.google.com", "time3.google.com", "time4.google.com", "0.fedora.pool.ntp.org") {
- r = manager_add_server(m, x);
- if (r < 0) {
- log_error("Failed to add server %s: %s", x, strerror(-r));
+ if (network_is_online()) {
+ r = manager_connect(m);
+ if (r < 0)
goto out;
- }
}
- r = manager_connect(m);
- if (r < 0)
- goto out;
-
r = sd_event_loop(m->event);
if (r < 0) {
log_error("Failed to run event loop: %s", strerror(-r));
sd_event_get_exit_code(m->event, &r);
out:
+ sd_notify(false, "STATUS=Shutting down...");
+
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}