timedated.c revision f38857914ab5c9cc55aac05795e1886963a5fd04
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2011 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 <string.h>
#include <unistd.h>
#include <sys/capability.h>
#include "sd-id128.h"
#include "sd-messages.h"
#include "sd-event.h"
#include "sd-bus.h"
#include "util.h"
#include "strv.h"
#include "def.h"
#include "clock-util.h"
#include "conf-files.h"
#include "path-util.h"
#include "fileio-label.h"
#include "label.h"
#include "bus-util.h"
#include "bus-errors.h"
#include "event-util.h"
#define NULL_ADJTIME_UTC "0.0 0 0\n0\nUTC\n"
#define NULL_ADJTIME_LOCAL "0.0 0 0\n0\nLOCAL\n"
typedef struct Context {
char *zone;
bool local_rtc;
bool can_ntp;
bool use_ntp;
Hashmap *polkit_registry;
} Context;
static void context_free(Context *c) {
assert(c);
free(c->zone);
bus_verify_polkit_async_registry_free(c->polkit_registry);
}
static int context_read_data(Context *c) {
_cleanup_free_ char *t = NULL;
int r;
assert(c);
r = readlink_malloc("/etc/localtime", &t);
if (r < 0) {
if (r == -EINVAL)
log_warning("/etc/localtime should be a symbolic link to a time zone data file in /usr/share/zoneinfo/.");
else
log_warning("Failed to get target of /etc/localtime: %s", strerror(-r));
} else {
const char *e;
e = path_startswith(t, "/usr/share/zoneinfo/");
if (!e)
e = path_startswith(t, "../usr/share/zoneinfo/");
if (!e)
log_warning("/etc/localtime should be a symbolic link to a time zone data file in /usr/share/zoneinfo/.");
else {
c->zone = strdup(e);
if (!c->zone)
return log_oom();
goto have_timezone;
}
}
have_timezone:
if (isempty(c->zone)) {
free(c->zone);
c->zone = NULL;
}
c->local_rtc = clock_is_localtime() > 0;
return 0;
}
static int context_write_data_timezone(Context *c) {
_cleanup_free_ char *p = NULL;
int r = 0;
assert(c);
if (isempty(c->zone)) {
if (unlink("/etc/localtime") < 0 && errno != ENOENT)
r = -errno;
return r;
}
p = strappend("../usr/share/zoneinfo/", c->zone);
if (!p)
return log_oom();
r = symlink_atomic(p, "/etc/localtime");
if (r < 0)
return r;
return 0;
}
static int context_write_data_local_rtc(Context *c) {
int r;
_cleanup_free_ char *s = NULL, *w = NULL;
assert(c);
r = read_full_file("/etc/adjtime", &s, NULL);
if (r < 0) {
if (r != -ENOENT)
return r;
if (!c->local_rtc)
return 0;
w = strdup(NULL_ADJTIME_LOCAL);
if (!w)
return -ENOMEM;
} else {
char *p, *e;
size_t a, b;
p = strchr(s, '\n');
if (!p)
return -EIO;
p = strchr(p+1, '\n');
if (!p)
return -EIO;
p++;
e = strchr(p, '\n');
if (!e)
return -EIO;
a = p - s;
b = strlen(e);
w = new(char, a + (c->local_rtc ? 5 : 3) + b + 1);
if (!w)
return -ENOMEM;
*(char*) mempcpy(stpcpy(mempcpy(w, s, a), c->local_rtc ? "LOCAL" : "UTC"), e, b) = 0;
if (streq(w, NULL_ADJTIME_UTC)) {
if (unlink("/etc/adjtime") < 0)
if (errno != ENOENT)
return -errno;
return 0;
}
}
label_init("/etc");
return write_string_file_atomic_label("/etc/adjtime", w);
}
static int context_read_ntp(Context *c, sd_bus *bus) {
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
sd_bus_message *reply = NULL;
const char *s;
int r;
assert(c);
assert(bus);
r = sd_bus_call_method(
bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"GetUnitFileState",
&error,
&reply,
"s",
"systemd-timesyncd.service");
if (r < 0) {
if (sd_bus_error_has_name(&error, SD_BUS_ERROR_FILE_NOT_FOUND) ||
sd_bus_error_has_name(&error, "org.freedesktop.systemd1.LoadFailed") ||
sd_bus_error_has_name(&error, "org.freedesktop.systemd1.NoSuchUnit"))
return 0;
return r;
}
r = sd_bus_message_read(reply, "s", &s);
if (r < 0)
return r;
c->can_ntp = true;
c->use_ntp = STR_IN_SET(s, "enabled", "enabled-runtime");
return 0;
}
static int context_start_ntp(Context *c, sd_bus *bus, sd_bus_error *error) {
int r;
assert(c);
assert(bus);
assert(error);
if (c->use_ntp)
r = sd_bus_call_method(
bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"StartUnit",
error,
NULL,
"ss",
"systemd-timesyncd.service",
"replace");
else
r = sd_bus_call_method(
bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"StopUnit",
error,
NULL,
"ss",
"systemd-timesyncd.service",
"replace");
if (r < 0) {
if (sd_bus_error_has_name(error, SD_BUS_ERROR_FILE_NOT_FOUND) ||
sd_bus_error_has_name(error, "org.freedesktop.systemd1.LoadFailed") ||
sd_bus_error_has_name(error, "org.freedesktop.systemd1.NoSuchUnit")) {
sd_bus_error_set_const(error, "org.freedesktop.timedate1.NoNTPSupport", "NTP not supported.");
return -ENOTSUP;
}
return r;
}
return 0;
}
static int context_enable_ntp(Context*c, sd_bus *bus, sd_bus_error *error) {
int r;
assert(c);
assert(bus);
assert(error);
if (c->use_ntp)
r = sd_bus_call_method(
bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"EnableUnitFiles",
error,
NULL,
"asbb", 1,
"systemd-timesyncd.service",
false, true);
else
r = sd_bus_call_method(
bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"DisableUnitFiles",
error,
NULL,
"asb", 1,
"systemd-timesyncd.service",
false);
if (r < 0) {
if (sd_bus_error_has_name(error, SD_BUS_ERROR_FILE_NOT_FOUND)) {
sd_bus_error_set_const(error, "org.freedesktop.timedate1.NoNTPSupport", "NTP not supported.");
return -ENOTSUP;
}
return r;
}
r = sd_bus_call_method(
bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"Reload",
error,
NULL,
NULL);
if (r < 0)
return r;
return 0;
}
static int property_get_rtc_time(
sd_bus *bus,
const char *path,
const char *interface,
const char *property,
sd_bus_message *reply,
void *userdata,
sd_bus_error *error) {
struct tm tm;
usec_t t;
int r;
zero(tm);
r = clock_get_hwclock(&tm);
if (r == -EBUSY) {
log_warning("/dev/rtc is busy. Is somebody keeping it open continuously? That's not a good idea... Returning a bogus RTC timestamp.");
t = 0;
} else if (r == -ENOENT) {
log_debug("/dev/rtc not found.");
t = 0; /* no RTC found */
} else if (r < 0)
return sd_bus_error_set_errnof(error, r, "Failed to read RTC: %s", strerror(-r));
else
t = (usec_t) timegm(&tm) * USEC_PER_SEC;
return sd_bus_message_append(reply, "t", t);
}
static int property_get_time(
sd_bus *bus,
const char *path,
const char *interface,
const char *property,
sd_bus_message *reply,
void *userdata,
sd_bus_error *error) {
return sd_bus_message_append(reply, "t", now(CLOCK_REALTIME));
}
static int property_get_ntp_sync(
sd_bus *bus,
const char *path,
const char *interface,
const char *property,
sd_bus_message *reply,
void *userdata,
sd_bus_error *error) {
return sd_bus_message_append(reply, "b", ntp_synced());
}
static int method_set_timezone(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
Context *c = userdata;
const char *z;
int interactive;
char *t;
int r;
assert(bus);
assert(m);
assert(c);
r = sd_bus_message_read(m, "sb", &z, &interactive);
if (r < 0)
return r;
if (!timezone_is_valid(z))
return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid time zone '%s'", z);
if (streq_ptr(z, c->zone))
return sd_bus_reply_method_return(m, NULL);
r = bus_verify_polkit_async(m, CAP_SYS_TIME, "org.freedesktop.timedate1.set-timezone", interactive, &c->polkit_registry, error);
if (r < 0)
return r;
if (r == 0)
return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */
t = strdup(z);
if (!t)
return -ENOMEM;
free(c->zone);
c->zone = t;
/* 1. Write new configuration file */
r = context_write_data_timezone(c);
if (r < 0) {
log_error("Failed to set time zone: %s", strerror(-r));
return sd_bus_error_set_errnof(error, r, "Failed to set time zone: %s", strerror(-r));
}
/* 2. Tell the kernel our timezone */
clock_set_timezone(NULL);
if (c->local_rtc) {
struct timespec ts;
struct tm *tm;
/* 3. Sync RTC from system clock, with the new delta */
assert_se(clock_gettime(CLOCK_REALTIME, &ts) == 0);
assert_se(tm = localtime(&ts.tv_sec));
clock_set_hwclock(tm);
}
log_struct(LOG_INFO,
MESSAGE_ID(SD_MESSAGE_TIMEZONE_CHANGE),
"TIMEZONE=%s", c->zone,
"MESSAGE=Changed time zone to '%s'.", c->zone,
NULL);
sd_bus_emit_properties_changed(bus, "/org/freedesktop/timedate1", "org.freedesktop.timedate1", "Timezone", NULL);
return sd_bus_reply_method_return(m, NULL);
}
static int method_set_local_rtc(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
int lrtc, fix_system, interactive;
Context *c = userdata;
struct timespec ts;
int r;
assert(bus);
assert(m);
assert(c);
r = sd_bus_message_read(m, "bbb", &lrtc, &fix_system, &interactive);
if (r < 0)
return r;
if (lrtc == c->local_rtc)
return sd_bus_reply_method_return(m, NULL);
r = bus_verify_polkit_async(m, CAP_SYS_TIME, "org.freedesktop.timedate1.set-local-rtc", interactive, &c->polkit_registry, error);
if (r < 0)
return r;
if (r == 0)
return 1;
c->local_rtc = lrtc;
/* 1. Write new configuration file */
r = context_write_data_local_rtc(c);
if (r < 0) {
log_error("Failed to set RTC to local/UTC: %s", strerror(-r));
return sd_bus_error_set_errnof(error, r, "Failed to set RTC to local/UTC: %s", strerror(-r));
}
/* 2. Tell the kernel our timezone */
clock_set_timezone(NULL);
/* 3. Synchronize clocks */
assert_se(clock_gettime(CLOCK_REALTIME, &ts) == 0);
if (fix_system) {
struct tm tm;
/* Sync system clock from RTC; first,
* initialize the timezone fields of
* struct tm. */
if (c->local_rtc)
tm = *localtime(&ts.tv_sec);
else
tm = *gmtime(&ts.tv_sec);
/* Override the main fields of
* struct tm, but not the timezone
* fields */
if (clock_get_hwclock(&tm) >= 0) {
/* And set the system clock
* with this */
if (c->local_rtc)
ts.tv_sec = mktime(&tm);
else
ts.tv_sec = timegm(&tm);
clock_settime(CLOCK_REALTIME, &ts);
}
} else {
struct tm *tm;
/* Sync RTC from system clock */
if (c->local_rtc)
tm = localtime(&ts.tv_sec);
else
tm = gmtime(&ts.tv_sec);
clock_set_hwclock(tm);
}
log_info("RTC configured to %s time.", c->local_rtc ? "local" : "UTC");
sd_bus_emit_properties_changed(bus, "/org/freedesktop/timedate1", "org.freedesktop.timedate1", "LocalRTC", NULL);
return sd_bus_reply_method_return(m, NULL);
}
static int method_set_time(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
int relative, interactive;
Context *c = userdata;
int64_t utc;
struct timespec ts;
struct tm* tm;
int r;
assert(bus);
assert(m);
assert(c);
if (c->use_ntp)
return sd_bus_error_setf(error, BUS_ERROR_AUTOMATIC_TIME_SYNC_ENABLED, "Automatic time synchronization is enabled");
r = sd_bus_message_read(m, "xbb", &utc, &relative, &interactive);
if (r < 0)
return r;
if (!relative && utc <= 0)
return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid absolute time");
if (relative && utc == 0)
return sd_bus_reply_method_return(m, NULL);
if (relative) {
usec_t n, x;
n = now(CLOCK_REALTIME);
x = n + utc;
if ((utc > 0 && x < n) ||
(utc < 0 && x > n))
return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Time value overflow");
timespec_store(&ts, x);
} else
timespec_store(&ts, (usec_t) utc);
r = bus_verify_polkit_async(m, CAP_SYS_TIME, "org.freedesktop.timedate1.set-time", interactive, &c->polkit_registry, error);
if (r < 0)
return r;
if (r == 0)
return 1;
/* Set system clock */
if (clock_settime(CLOCK_REALTIME, &ts) < 0) {
log_error("Failed to set local time: %m");
return sd_bus_error_set_errnof(error, errno, "Failed to set local time: %m");
}
/* Sync down to RTC */
if (c->local_rtc)
tm = localtime(&ts.tv_sec);
else
tm = gmtime(&ts.tv_sec);
clock_set_hwclock(tm);
log_struct(LOG_INFO,
MESSAGE_ID(SD_MESSAGE_TIME_CHANGE),
"REALTIME="USEC_FMT, timespec_load(&ts),
"MESSAGE=Changed local time to %s", ctime(&ts.tv_sec),
NULL);
return sd_bus_reply_method_return(m, NULL);
}
static int method_set_ntp(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
int ntp, interactive;
Context *c = userdata;
int r;
r = sd_bus_message_read(m, "bb", &ntp, &interactive);
if (r < 0)
return r;
if ((bool)ntp == c->use_ntp)
return sd_bus_reply_method_return(m, NULL);
r = bus_verify_polkit_async(m, CAP_SYS_TIME, "org.freedesktop.timedate1.set-ntp", interactive, &c->polkit_registry, error);
if (r < 0)
return r;
if (r == 0)
return 1;
c->use_ntp = ntp;
r = context_enable_ntp(c, bus, error);
if (r < 0)
return r;
r = context_start_ntp(c, bus, error);
if (r < 0)
return r;
log_info("Set NTP to %s", c->use_ntp ? "enabled" : "disabled");
sd_bus_emit_properties_changed(bus, "/org/freedesktop/timedate1", "org.freedesktop.timedate1", "NTP", NULL);
return sd_bus_reply_method_return(m, NULL);
}
static const sd_bus_vtable timedate_vtable[] = {
SD_BUS_VTABLE_START(0),
SD_BUS_PROPERTY("Timezone", "s", NULL, offsetof(Context, zone), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
SD_BUS_PROPERTY("LocalRTC", "b", bus_property_get_bool, offsetof(Context, local_rtc), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
SD_BUS_PROPERTY("CanNTP", "b", bus_property_get_bool, offsetof(Context, can_ntp), 0),
SD_BUS_PROPERTY("NTP", "b", bus_property_get_bool, offsetof(Context, use_ntp), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
SD_BUS_PROPERTY("NTPSynchronized", "b", property_get_ntp_sync, 0, 0),
SD_BUS_PROPERTY("TimeUSec", "t", property_get_time, 0, 0),
SD_BUS_PROPERTY("RTCTimeUSec", "t", property_get_rtc_time, 0, 0),
SD_BUS_METHOD("SetTime", "xbb", NULL, method_set_time, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("SetTimezone", "sb", NULL, method_set_timezone, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("SetLocalRTC", "bbb", NULL, method_set_local_rtc, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("SetNTP", "bb", NULL, method_set_ntp, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_VTABLE_END,
};
static int connect_bus(Context *c, sd_event *event, sd_bus **_bus) {
_cleanup_bus_close_unref_ sd_bus *bus = NULL;
int r;
assert(c);
assert(event);
assert(_bus);
r = sd_bus_default_system(&bus);
if (r < 0) {
log_error("Failed to get system bus connection: %s", strerror(-r));
return r;
}
r = sd_bus_add_object_vtable(bus, NULL, "/org/freedesktop/timedate1", "org.freedesktop.timedate1", timedate_vtable, c);
if (r < 0) {
log_error("Failed to register object: %s", strerror(-r));
return r;
}
r = sd_bus_request_name(bus, "org.freedesktop.timedate1", 0);
if (r < 0) {
log_error("Failed to register name: %s", strerror(-r));
return r;
}
r = sd_bus_attach_event(bus, event, 0);
if (r < 0) {
log_error("Failed to attach bus to event loop: %s", strerror(-r));
return r;
}
*_bus = bus;
bus = NULL;
return 0;
}
int main(int argc, char *argv[]) {
Context context = {};
_cleanup_event_unref_ sd_event *event = NULL;
_cleanup_bus_close_unref_ sd_bus *bus = NULL;
int r;
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
if (argc != 1) {
log_error("This program takes no arguments.");
r = -EINVAL;
goto finish;
}
r = sd_event_default(&event);
if (r < 0) {
log_error("Failed to allocate event loop: %s", strerror(-r));
goto finish;
}
sd_event_set_watchdog(event, true);
r = connect_bus(&context, event, &bus);
if (r < 0)
goto finish;
r = context_read_data(&context);
if (r < 0) {
log_error("Failed to read time zone data: %s", strerror(-r));
goto finish;
}
r = context_read_ntp(&context, bus);
if (r < 0) {
log_error("Failed to determine whether NTP is enabled: %s", strerror(-r));
goto finish;
}
r = bus_event_loop_with_idle(event, bus, "org.freedesktop.timedate1", DEFAULT_EXIT_USEC, NULL, NULL);
if (r < 0) {
log_error("Failed to run event loop: %s", strerror(-r));
goto finish;
}
finish:
context_free(&context);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}