update-utmp.c revision 4cfa2c999dea269ddc646bfeba6c7f1021a73843
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 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
General Public License for more details.
You should have received a copy of the GNU General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <assert.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <dbus/dbus.h>
#ifdef HAVE_AUDIT
#include <libaudit.h>
#endif
#include "log.h"
#include "macro.h"
#include "util.h"
#include "special.h"
#include "utmp-wtmp.h"
#include "dbus-common.h"
typedef struct Context {
DBusConnection *bus;
#ifdef HAVE_AUDIT
int audit_fd;
#endif
} Context;
static usec_t get_startup_time(Context *c) {
const char
*interface = "org.freedesktop.systemd1.Manager",
*property = "StartupTimestamp";
DBusError error;
usec_t t = 0;
DBusMessage *m = NULL, *reply = NULL;
DBusMessageIter iter, sub;
dbus_error_init(&error);
assert(c);
if (!(m = dbus_message_new_method_call(
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.DBus.Properties",
"Get"))) {
log_error("Could not allocate message.");
goto finish;
}
if (!dbus_message_append_args(m,
DBUS_TYPE_STRING, &interface,
DBUS_TYPE_STRING, &property,
DBUS_TYPE_INVALID)) {
log_error("Could not append arguments to message.");
goto finish;
}
if (!(reply = dbus_connection_send_with_reply_and_block(c->bus, m, -1, &error))) {
log_error("Failed to send command: %s", bus_error_message(&error));
goto finish;
}
if (!dbus_message_iter_init(reply, &iter) ||
dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_VARIANT) {
log_error("Failed to parse reply.");
goto finish;
}
dbus_message_iter_recurse(&iter, &sub);
if (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_UINT64) {
log_error("Failed to parse reply.");
goto finish;
}
dbus_message_iter_get_basic(&sub, &t);
finish:
if (m)
dbus_message_unref(m);
if (reply)
dbus_message_unref(reply);
dbus_error_free(&error);
return t;
}
static int get_current_runlevel(Context *c) {
static const struct {
const int runlevel;
const char *special;
} table[] = {
/* The first target of this list that is active or has
* a job scheduled wins. We prefer runlevels 5 and 3
* here over the others, since these are the main
* runlevels used on Fedora. It might make sense to
* change the order on some distributions. */
{ '5', SPECIAL_RUNLEVEL5_TARGET },
{ '3', SPECIAL_RUNLEVEL3_TARGET },
{ '4', SPECIAL_RUNLEVEL4_TARGET },
{ '2', SPECIAL_RUNLEVEL2_TARGET },
{ 'S', SPECIAL_RESCUE_TARGET },
};
const char
*interface = "org.freedesktop.systemd1.Unit",
*property = "ActiveState";
DBusMessage *m = NULL, *reply = NULL;
int r = 0;
unsigned i;
DBusError error;
assert(c);
dbus_error_init(&error);
for (i = 0; i < ELEMENTSOF(table); i++) {
const char *path = NULL, *state;
DBusMessageIter iter, sub;
if (!(m = dbus_message_new_method_call(
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"GetUnit"))) {
log_error("Could not allocate message.");
r = -ENOMEM;
goto finish;
}
if (!dbus_message_append_args(m,
DBUS_TYPE_STRING, &table[i].special,
DBUS_TYPE_INVALID)) {
log_error("Could not append arguments to message.");
r = -ENOMEM;
goto finish;
}
if (!(reply = dbus_connection_send_with_reply_and_block(c->bus, m, -1, &error))) {
dbus_error_free(&error);
continue;
}
if (!dbus_message_get_args(reply, &error,
DBUS_TYPE_OBJECT_PATH, &path,
DBUS_TYPE_INVALID)) {
log_error("Failed to parse reply: %s", bus_error_message(&error));
r = -EIO;
goto finish;
}
dbus_message_unref(m);
if (!(m = dbus_message_new_method_call(
"org.freedesktop.systemd1",
path,
"org.freedesktop.DBus.Properties",
"Get"))) {
log_error("Could not allocate message.");
r = -ENOMEM;
goto finish;
}
if (!dbus_message_append_args(m,
DBUS_TYPE_STRING, &interface,
DBUS_TYPE_STRING, &property,
DBUS_TYPE_INVALID)) {
log_error("Could not append arguments to message.");
r = -ENOMEM;
goto finish;
}
dbus_message_unref(reply);
if (!(reply = dbus_connection_send_with_reply_and_block(c->bus, m, -1, &error))) {
log_error("Failed to send command: %s", bus_error_message(&error));
r = -EIO;
goto finish;
}
if (!dbus_message_iter_init(reply, &iter) ||
dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_VARIANT) {
log_error("Failed to parse reply.");
r = -EIO;
goto finish;
}
dbus_message_iter_recurse(&iter, &sub);
if (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_STRING) {
log_error("Failed to parse reply.");
r = -EIO;
goto finish;
}
dbus_message_iter_get_basic(&sub, &state);
if (streq(state, "active") || streq(state, "reloading"))
r = table[i].runlevel;
dbus_message_unref(m);
dbus_message_unref(reply);
m = reply = NULL;
if (r)
break;
}
finish:
if (m)
dbus_message_unref(m);
if (reply)
dbus_message_unref(reply);
dbus_error_free(&error);
return r;
}
static int on_reboot(Context *c) {
int r = 0, q;
usec_t t;
assert(c);
/* We finished start-up, so let's write the utmp
* record and send the audit msg */
#ifdef HAVE_AUDIT
if (c->audit_fd >= 0)
if (audit_log_user_message(c->audit_fd, AUDIT_SYSTEM_BOOT, "init", NULL, NULL, NULL, 1) < 0) {
log_error("Failed to send audit message: %m");
r = -errno;
}
#endif
/* If this call fails it will return 0, which
* utmp_put_reboot() will then fix to the current time */
t = get_startup_time(c);
if ((q = utmp_put_reboot(t)) < 0) {
log_error("Failed to write utmp record: %s", strerror(-q));
r = q;
}
return r;
}
static int on_shutdown(Context *c) {
int r = 0, q;
assert(c);
/* We started shut-down, so let's write the utmp
* record and send the audit msg */
#ifdef HAVE_AUDIT
if (c->audit_fd >= 0)
if (audit_log_user_message(c->audit_fd, AUDIT_SYSTEM_SHUTDOWN, "init", NULL, NULL, NULL, 1) < 0) {
log_error("Failed to send audit message: %m");
r = -errno;
}
#endif
if ((q = utmp_put_shutdown()) < 0) {
log_error("Failed to write utmp record: %s", strerror(-q));
r = q;
}
return r;
}
static int on_runlevel(Context *c) {
int r = 0, q, previous, runlevel;
assert(c);
/* We finished changing runlevel, so let's write the
* utmp record and send the audit msg */
/* First, get last runlevel */
if ((q = utmp_get_runlevel(&previous, NULL)) < 0) {
if (q != -ESRCH && q != -ENOENT) {
log_error("Failed to get current runlevel: %s", strerror(-q));
return q;
}
/* Hmm, we didn't find any runlevel, that means we
* have been rebooted */
r = on_reboot(c);
previous = 0;
}
/* Secondly, get new runlevel */
if ((runlevel = get_current_runlevel(c)) < 0)
return runlevel;
if (previous == runlevel)
return 0;
#ifdef HAVE_AUDIT
if (c->audit_fd >= 0) {
char *s = NULL;
if (asprintf(&s, "old-level=%c new-level=%c",
previous > 0 ? previous : 'N',
runlevel > 0 ? runlevel : 'N') < 0)
return -ENOMEM;
if (audit_log_user_message(c->audit_fd, AUDIT_SYSTEM_RUNLEVEL, s, NULL, NULL, NULL, 1) < 0) {
log_error("Failed to send audit message: %m");
r = -errno;
}
free(s);
}
#endif
if ((q = utmp_put_runlevel(runlevel, previous)) < 0) {
log_error("Failed to write utmp record: %s", strerror(-q));
r = q;
}
return r;
}
int main(int argc, char *argv[]) {
int r;
DBusError error;
Context c;
dbus_error_init(&error);
zero(c);
#ifdef HAVE_AUDIT
c.audit_fd = -1;
#endif
if (getppid() != 1) {
log_error("This program should be invoked by init only.");
return EXIT_FAILURE;
}
if (argc != 2) {
log_error("This program requires one argument.");
return EXIT_FAILURE;
}
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
#ifdef HAVE_AUDIT
if ((c.audit_fd = audit_open()) < 0 &&
/* If the kernel lacks netlink or audit support,
* don't worry about it. */
errno != EAFNOSUPPORT && errno != EPROTONOSUPPORT)
log_error("Failed to connect to audit log: %m");
#endif
if (bus_connect(DBUS_BUS_SYSTEM, &c.bus, NULL, &error) < 0) {
log_error("Failed to get D-Bus connection: %s", bus_error_message(&error));
r = -EIO;
goto finish;
}
log_debug("systemd-update-utmp running as pid %lu", (unsigned long) getpid());
if (streq(argv[1], "reboot"))
r = on_reboot(&c);
else if (streq(argv[1], "shutdown"))
r = on_shutdown(&c);
else if (streq(argv[1], "runlevel"))
r = on_runlevel(&c);
else {
log_error("Unknown command %s", argv[1]);
r = -EINVAL;
}
log_debug("systemd-update-utmp stopped as pid %lu", (unsigned long) getpid());
finish:
#ifdef HAVE_AUDIT
if (c.audit_fd >= 0)
audit_close(c.audit_fd);
#endif
if (c.bus) {
dbus_connection_flush(c.bus);
dbus_connection_close(c.bus);
dbus_connection_unref(c.bus);
}
dbus_error_free(&error);
dbus_shutdown();
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}