2 * Copyright (C) 2004-2011 Kay Sievers <kay.sievers@vrfy.org>
3 * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
4 * Copyright (C) 2009 Canonical Ltd.
5 * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
35 #include <sys/prctl.h>
36 #include <sys/socket.h>
38 #include <sys/signalfd.h>
39 #include <sys/epoll.h>
43 #include <sys/ioctl.h>
44 #include <sys/inotify.h>
45 #include <sys/utsname.h>
48 #include "sd-daemon.h"
50 #define UDEVD_PRIORITY -4
51 #define UDEV_PRIORITY -2
55 static void log_fn(struct udev *udev, int priority,
56 const char *file, int line, const char *fn,
57 const char *format, va_list args)
64 vsnprintf(buf, sizeof(buf), format, args);
65 gettimeofday(&tv, &tz);
66 fprintf(stderr, "%llu.%06u [%u] %s: %s",
67 (unsigned long long) tv.tv_sec, (unsigned int) tv.tv_usec,
68 (int) getpid(), fn, buf);
70 vsyslog(priority, format, args);
74 static struct udev_rules *rules;
75 static struct udev_queue_export *udev_queue_export;
76 static struct udev_ctrl *udev_ctrl;
77 static struct udev_monitor *monitor;
78 static int worker_watch[2] = { -1, -1 };
79 static int fd_signal = -1;
80 static int fd_ep = -1;
81 static int fd_inotify = -1;
82 static bool stop_exec_queue;
83 static bool reload_config;
85 static int children_max;
86 static int exec_delay;
87 static sigset_t orig_sigmask;
88 static UDEV_LIST(event_list);
89 static UDEV_LIST(worker_list);
90 static bool udev_exit;
91 static volatile sig_atomic_t worker_exit;
100 struct udev_list_node node;
102 struct udev_device *dev;
103 enum event_state state;
105 unsigned long long int delaying_seqnum;
106 unsigned long long int seqnum;
109 const char *devpath_old;
115 static struct event *node_to_event(struct udev_list_node *node)
119 event = (char *)node;
120 event -= offsetof(struct event, node);
121 return (struct event *)event;
124 static void event_queue_cleanup(struct udev *udev, enum event_state type);
134 struct udev_list_node node;
138 struct udev_monitor *monitor;
139 enum worker_state state;
143 /* passed from worker to main process */
144 struct worker_message {
149 static struct worker *node_to_worker(struct udev_list_node *node)
153 worker = (char *)node;
154 worker -= offsetof(struct worker, node);
155 return (struct worker *)worker;
158 static void event_queue_delete(struct event *event, bool export)
160 udev_list_node_remove(&event->node);
163 /* mark as failed, if "add" event returns non-zero */
164 if (event->exitcode != 0 && strcmp(udev_device_get_action(event->dev), "remove") != 0)
165 udev_queue_export_device_failed(udev_queue_export, event->dev);
167 udev_queue_export_device_finished(udev_queue_export, event->dev);
168 info(event->udev, "seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
170 udev_device_unref(event->dev);
174 static void event_sig_handler(int signum)
186 static struct worker *worker_ref(struct worker *worker)
192 static void worker_cleanup(struct worker *worker)
194 udev_list_node_remove(&worker->node);
195 udev_monitor_unref(worker->monitor);
200 static void worker_unref(struct worker *worker)
203 if (worker->refcount > 0)
205 info(worker->udev, "worker [%u] cleaned up\n", worker->pid);
206 worker_cleanup(worker);
209 static void worker_list_cleanup(struct udev *udev)
211 struct udev_list_node *loop, *tmp;
213 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
214 struct worker *worker = node_to_worker(loop);
216 worker_cleanup(worker);
220 static void worker_new(struct event *event)
222 struct udev *udev = event->udev;
223 struct worker *worker;
224 struct udev_monitor *worker_monitor;
226 struct sigaction act;
228 /* listen for new events */
229 worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
230 if (worker_monitor == NULL)
232 /* allow the main daemon netlink address to send devices to the worker */
233 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
234 udev_monitor_enable_receiving(worker_monitor);
236 worker = calloc(1, sizeof(struct worker));
237 if (worker == NULL) {
238 udev_monitor_unref(worker_monitor);
241 /* worker + event reference */
242 worker->refcount = 2;
249 struct udev_device *dev;
250 struct pollfd pmon = {
251 .fd = udev_monitor_get_fd(worker_monitor),
255 /* move initial device from queue */
260 worker_list_cleanup(udev);
261 event_queue_cleanup(udev, EVENT_UNDEF);
262 udev_queue_export_unref(udev_queue_export);
263 udev_monitor_unref(monitor);
264 udev_ctrl_unref(udev_ctrl);
267 close(worker_watch[READ_END]);
269 udev_log_init("udevd-work");
270 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
272 /* set signal handlers */
273 memset(&act, 0x00, sizeof(act));
274 act.sa_handler = event_sig_handler;
275 sigemptyset (&act.sa_mask);
277 sigaction(SIGTERM, &act, NULL);
278 sigaction(SIGALRM, &act, NULL);
280 /* unblock SIGALRM */
281 sigfillset(&sigmask);
282 sigdelset(&sigmask, SIGALRM);
283 sigprocmask(SIG_SETMASK, &sigmask, NULL);
284 /* SIGTERM is unblocked in ppoll() */
285 sigdelset(&sigmask, SIGTERM);
287 /* request TERM signal if parent exits */
288 prctl(PR_SET_PDEATHSIG, SIGTERM);
291 struct udev_event *udev_event;
292 struct worker_message msg = {};
296 info(udev, "seq %llu running\n", udev_device_get_seqnum(dev));
297 udev_event = udev_event_new(dev);
298 if (udev_event == NULL)
301 /* set timeout to prevent hanging processes */
302 alarm(UDEV_EVENT_TIMEOUT);
305 udev_event->exec_delay = exec_delay;
307 /* apply rules, create node, symlinks */
308 err = udev_event_execute_rules(udev_event, rules);
310 /* rules may change/disable the timeout */
311 if (udev_device_get_event_timeout(dev) >= 0)
312 alarm(udev_device_get_event_timeout(dev));
315 failed = udev_event_execute_run(udev_event, &orig_sigmask);
319 /* apply/restore inotify watch */
320 if (err == 0 && udev_event->inotify_watch) {
321 udev_watch_begin(udev, dev);
322 udev_device_update_db(dev);
325 /* send processed event back to libudev listeners */
326 udev_monitor_send_device(worker_monitor, NULL, dev);
328 /* send udevd the result of the event execution */
331 else if (failed != 0)
332 msg.exitcode = failed;
334 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
336 info(udev, "seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
337 udev_event_unref(udev_event);
338 udev_device_unref(dev);
341 /* wait for more device messages or signal from udevd */
342 while (!worker_exit) {
345 fdcount = ppoll(&pmon, 1, NULL, &sigmask);
349 if (pmon.revents & POLLIN) {
350 dev = udev_monitor_receive_device(worker_monitor);
355 } while (dev != NULL);
358 close(worker_watch[WRITE_END]);
359 udev_rules_unref(rules);
360 udev_monitor_unref(worker_monitor);
366 udev_monitor_unref(worker_monitor);
367 event->state = EVENT_QUEUED;
369 err(udev, "fork of child failed: %m\n");
372 /* close monitor, but keep address around */
373 udev_monitor_disconnect(worker_monitor);
374 worker->monitor = worker_monitor;
376 worker->state = WORKER_RUNNING;
377 worker->event = event;
378 event->state = EVENT_RUNNING;
379 udev_list_node_append(&worker->node, &worker_list);
381 info(udev, "seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
386 static void event_run(struct event *event, bool force)
388 struct udev_list_node *loop;
390 udev_list_node_foreach(loop, &worker_list) {
391 struct worker *worker = node_to_worker(loop);
394 if (worker->state != WORKER_IDLE)
397 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
399 err(event->udev, "worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
400 kill(worker->pid, SIGKILL);
401 worker->state = WORKER_KILLED;
405 worker->event = event;
406 worker->state = WORKER_RUNNING;
407 event->state = EVENT_RUNNING;
411 if (!force && children >= children_max) {
412 if (children_max > 1)
413 info(event->udev, "maximum number (%i) of children reached\n", children);
417 /* start new worker and pass initial device */
421 static int event_queue_insert(struct udev_device *dev)
425 event = calloc(1, sizeof(struct event));
429 event->udev = udev_device_get_udev(dev);
431 event->seqnum = udev_device_get_seqnum(dev);
432 event->devpath = udev_device_get_devpath(dev);
433 event->devpath_len = strlen(event->devpath);
434 event->devpath_old = udev_device_get_devpath_old(dev);
435 event->devnum = udev_device_get_devnum(dev);
436 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
437 event->ifindex = udev_device_get_ifindex(dev);
439 udev_queue_export_device_queued(udev_queue_export, dev);
440 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
441 udev_device_get_action(dev), udev_device_get_subsystem(dev));
443 event->state = EVENT_QUEUED;
444 udev_list_node_append(&event->node, &event_list);
446 /* run all events with a timeout set immediately */
447 if (udev_device_get_timeout(dev) > 0) {
448 event_run(event, true);
455 static void worker_kill(struct udev *udev, int retain)
457 struct udev_list_node *loop;
460 if (children <= retain)
463 max = children - retain;
465 udev_list_node_foreach(loop, &worker_list) {
466 struct worker *worker = node_to_worker(loop);
471 if (worker->state == WORKER_KILLED)
474 worker->state = WORKER_KILLED;
475 kill(worker->pid, SIGTERM);
479 /* lookup event for identical, parent, child device */
480 static bool is_devpath_busy(struct event *event)
482 struct udev_list_node *loop;
485 /* check if queue contains events we depend on */
486 udev_list_node_foreach(loop, &event_list) {
487 struct event *loop_event = node_to_event(loop);
489 /* we already found a later event, earlier can not block us, no need to check again */
490 if (loop_event->seqnum < event->delaying_seqnum)
493 /* event we checked earlier still exists, no need to check again */
494 if (loop_event->seqnum == event->delaying_seqnum)
497 /* found ourself, no later event can block us */
498 if (loop_event->seqnum >= event->seqnum)
501 /* check major/minor */
502 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
505 /* check network device ifindex */
506 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
509 /* check our old name */
510 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
511 event->delaying_seqnum = loop_event->seqnum;
515 /* compare devpath */
516 common = MIN(loop_event->devpath_len, event->devpath_len);
518 /* one devpath is contained in the other? */
519 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
522 /* identical device event found */
523 if (loop_event->devpath_len == event->devpath_len) {
524 /* devices names might have changed/swapped in the meantime */
525 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
527 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
529 event->delaying_seqnum = loop_event->seqnum;
533 /* parent device event found */
534 if (event->devpath[common] == '/') {
535 event->delaying_seqnum = loop_event->seqnum;
539 /* child device event found */
540 if (loop_event->devpath[common] == '/') {
541 event->delaying_seqnum = loop_event->seqnum;
545 /* no matching device */
552 static void event_queue_start(struct udev *udev)
554 struct udev_list_node *loop;
556 udev_list_node_foreach(loop, &event_list) {
557 struct event *event = node_to_event(loop);
559 if (event->state != EVENT_QUEUED)
562 /* do not start event if parent or child event is still running */
563 if (is_devpath_busy(event)) {
564 dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath);
568 event_run(event, false);
572 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
574 struct udev_list_node *loop, *tmp;
576 udev_list_node_foreach_safe(loop, tmp, &event_list) {
577 struct event *event = node_to_event(loop);
579 if (match_type != EVENT_UNDEF && match_type != event->state)
582 event_queue_delete(event, false);
586 static void worker_returned(int fd_worker)
589 struct worker_message msg;
591 struct udev_list_node *loop;
593 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
594 if (size != sizeof(struct worker_message))
597 /* lookup worker who sent the signal */
598 udev_list_node_foreach(loop, &worker_list) {
599 struct worker *worker = node_to_worker(loop);
601 if (worker->pid != msg.pid)
604 /* worker returned */
605 worker->event->exitcode = msg.exitcode;
606 event_queue_delete(worker->event, true);
607 worker->event = NULL;
608 if (worker->state != WORKER_KILLED)
609 worker->state = WORKER_IDLE;
610 worker_unref(worker);
616 /* receive the udevd message from userspace */
617 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
619 struct udev *udev = udev_ctrl_get_udev(uctrl);
620 struct udev_ctrl_connection *ctrl_conn;
621 struct udev_ctrl_msg *ctrl_msg = NULL;
625 ctrl_conn = udev_ctrl_get_connection(uctrl);
626 if (ctrl_conn == NULL)
629 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
630 if (ctrl_msg == NULL)
633 i = udev_ctrl_get_set_log_level(ctrl_msg);
635 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
636 udev_set_log_priority(udev, i);
637 worker_kill(udev, 0);
640 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
641 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
642 stop_exec_queue = true;
645 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
646 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
647 stop_exec_queue = false;
650 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
651 info(udev, "udevd message (RELOAD_RULES) received\n");
652 reload_config = true;
655 str = udev_ctrl_get_set_env(ctrl_msg);
663 val = strchr(key, '=');
667 if (val[0] == '\0') {
668 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
669 udev_add_property(udev, key, NULL);
671 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
672 udev_add_property(udev, key, val);
675 err(udev, "wrong key format '%s'\n", key);
679 worker_kill(udev, 0);
682 i = udev_ctrl_get_set_children_max(ctrl_msg);
684 info(udev, "udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
688 if (udev_ctrl_get_ping(ctrl_msg) > 0)
689 info(udev, "udevd message (SYNC) received\n");
691 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
692 info(udev, "udevd message (EXIT) received\n");
694 /* keep reference to block the client until we exit */
695 udev_ctrl_connection_ref(ctrl_conn);
698 udev_ctrl_msg_unref(ctrl_msg);
699 return udev_ctrl_connection_unref(ctrl_conn);
702 /* read inotify messages */
703 static int handle_inotify(struct udev *udev)
707 struct inotify_event *ev;
709 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
712 buf = malloc(nbytes);
714 err(udev, "error getting buffer for inotify\n");
718 nbytes = read(fd_inotify, buf, nbytes);
720 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
721 struct udev_device *dev;
723 ev = (struct inotify_event *)(buf + pos);
727 info(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
728 s = strstr(ev->name, ".rules");
731 if (strlen(s) != strlen(".rules"))
733 reload_config = true;
737 dev = udev_watch_lookup(udev, ev->wd);
739 info(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
740 if (ev->mask & IN_CLOSE_WRITE) {
741 char filename[UTIL_PATH_SIZE];
744 info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
745 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
746 fd = open(filename, O_WRONLY);
747 if (fd < 0 || write(fd, "change", 6) < 0)
748 info(udev, "error writing uevent: %m\n");
751 if (ev->mask & IN_IGNORED)
752 udev_watch_end(udev, dev);
754 udev_device_unref(dev);
763 static void handle_signal(struct udev *udev, int signo)
774 struct udev_list_node *loop, *tmp;
776 pid = waitpid(-1, &status, WNOHANG);
780 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
781 struct worker *worker = node_to_worker(loop);
783 if (worker->pid != pid)
786 info(udev, "worker [%u] exit\n", pid);
787 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
788 err(udev, "worker [%u] unexpectedly returned with status 0x%04x\n", pid, status);
789 if (worker->event != NULL) {
790 err(udev, "worker [%u] failed while handling '%s'\n", pid, worker->event->devpath);
791 worker->event->exitcode = -32;
792 event_queue_delete(worker->event, true);
793 /* drop reference from running event */
794 worker_unref(worker);
797 worker_unref(worker);
803 reload_config = true;
808 static void static_dev_create_from_modules(struct udev *udev)
810 struct utsname kernel;
811 char modules[UTIL_PATH_SIZE];
816 util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
817 f = fopen(modules, "r");
821 while (fgets(buf, sizeof(buf), f) != NULL) {
829 char filename[UTIL_PATH_SIZE];
835 s = strchr(modname, ' ');
841 s = strchr(devname, ' ');
847 s = strchr(devno, ' ');
849 s = strchr(devno, '\n');
852 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
856 mode = 0600 | S_IFCHR;
857 else if (type == 'b')
858 mode = 0600 | S_IFBLK;
862 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
863 util_create_path_selinux(udev, filename);
864 udev_selinux_setfscreatecon(udev, filename, mode);
865 info(udev, "mknod '%s' %c%u:%u\n", filename, type, maj, min);
866 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
867 utimensat(AT_FDCWD, filename, NULL, 0);
868 udev_selinux_resetfscreatecon(udev);
874 static int copy_dev_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
878 for (dent = readdir(dir_from); dent != NULL; dent = readdir(dir_from)) {
881 if (dent->d_name[0] == '.')
883 if (fstatat(dirfd(dir_from), dent->d_name, &stats, AT_SYMLINK_NOFOLLOW) != 0)
886 if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
887 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, stats.st_mode & 0777);
888 if (mknodat(dirfd(dir_to), dent->d_name, stats.st_mode, stats.st_rdev) == 0) {
889 fchmodat(dirfd(dir_to), dent->d_name, stats.st_mode & 0777, 0);
890 fchownat(dirfd(dir_to), dent->d_name, stats.st_uid, stats.st_gid, 0);
892 utimensat(dirfd(dir_to), dent->d_name, NULL, 0);
894 udev_selinux_resetfscreatecon(udev);
895 } else if (S_ISLNK(stats.st_mode)) {
896 char target[UTIL_PATH_SIZE];
899 len = readlinkat(dirfd(dir_from), dent->d_name, target, sizeof(target));
900 if (len <= 0 || len == (ssize_t)sizeof(target))
903 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFLNK);
904 if (symlinkat(target, dirfd(dir_to), dent->d_name) < 0 && errno == EEXIST)
905 utimensat(dirfd(dir_to), dent->d_name, NULL, AT_SYMLINK_NOFOLLOW);
906 udev_selinux_resetfscreatecon(udev);
907 } else if (S_ISDIR(stats.st_mode)) {
908 DIR *dir2_from, *dir2_to;
913 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFDIR|0755);
914 mkdirat(dirfd(dir_to), dent->d_name, 0755);
915 udev_selinux_resetfscreatecon(udev);
917 dir2_to = fdopendir(openat(dirfd(dir_to), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
921 dir2_from = fdopendir(openat(dirfd(dir_from), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
922 if (dir2_from == NULL) {
927 copy_dev_dir(udev, dir2_from, dir2_to, maxdepth-1);
937 static void static_dev_create_links(struct udev *udev, DIR *dir)
943 static const struct stdlinks stdlinks[] = {
944 { "core", "/proc/kcore" },
945 { "fd", "/proc/self/fd" },
946 { "stdin", "/proc/self/fd/0" },
947 { "stdout", "/proc/self/fd/1" },
948 { "stderr", "/proc/self/fd/2" },
952 for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
955 if (stat(stdlinks[i].target, &sb) == 0) {
956 udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
957 if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
958 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
959 udev_selinux_resetfscreatecon(udev);
964 static void static_dev_create_from_devices(struct udev *udev, DIR *dir)
968 dir_from = opendir(LIBEXECDIR "/devices");
969 if (dir_from == NULL)
971 copy_dev_dir(udev, dir_from, dir, 8);
975 static void static_dev_create(struct udev *udev)
979 dir = opendir(udev_get_dev_path(udev));
983 static_dev_create_links(udev, dir);
984 static_dev_create_from_devices(udev, dir);
989 static int mem_size_mb(void)
993 long int memsize = -1;
995 f = fopen("/proc/meminfo", "r");
999 while (fgets(buf, sizeof(buf), f) != NULL) {
1002 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
1003 memsize = value / 1024;
1012 static int convert_db(struct udev *udev)
1014 char filename[UTIL_PATH_SIZE];
1016 struct udev_enumerate *udev_enumerate;
1017 struct udev_list_entry *list_entry;
1019 /* current database */
1020 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/data", NULL);
1021 if (access(filename, F_OK) >= 0)
1024 /* make sure we do not get here again */
1025 util_create_path(udev, filename);
1026 mkdir(filename, 0755);
1029 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/db", NULL);
1030 if (access(filename, F_OK) < 0)
1033 f = fopen("/dev/kmsg", "w");
1035 fprintf(f, "<30>udev[%u]: converting old udev database\n", getpid());
1039 udev_enumerate = udev_enumerate_new(udev);
1040 if (udev_enumerate == NULL)
1042 udev_enumerate_scan_devices(udev_enumerate);
1043 udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
1044 struct udev_device *device;
1046 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
1050 /* try to find the old database for devices without a current one */
1051 if (udev_device_read_db(device, NULL) < 0) {
1055 char devpath[UTIL_PATH_SIZE];
1056 char from[UTIL_PATH_SIZE];
1060 /* find database in old location */
1061 id = udev_device_get_id_filename(device);
1062 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
1063 if (lstat(from, &stats) == 0) {
1065 udev_device_read_db(device, from);
1071 /* find old database with $subsys:$sysname name */
1072 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
1073 "/.udev/db/", udev_device_get_subsystem(device), ":",
1074 udev_device_get_sysname(device), NULL);
1075 if (lstat(from, &stats) == 0) {
1077 udev_device_read_db(device, from);
1083 /* find old database with the encoded devpath name */
1084 util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
1085 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", devpath, NULL);
1086 if (lstat(from, &stats) == 0) {
1088 udev_device_read_db(device, from);
1094 /* write out new database */
1096 udev_device_update_db(device);
1098 udev_device_unref(device);
1100 udev_enumerate_unref(udev_enumerate);
1104 int main(int argc, char *argv[])
1110 int daemonize = false;
1111 int resolve_names = 1;
1112 static const struct option options[] = {
1113 { "daemon", no_argument, NULL, 'd' },
1114 { "debug", no_argument, NULL, 'D' },
1115 { "children-max", required_argument, NULL, 'c' },
1116 { "exec-delay", required_argument, NULL, 'e' },
1117 { "resolve-names", required_argument, NULL, 'N' },
1118 { "help", no_argument, NULL, 'h' },
1119 { "version", no_argument, NULL, 'V' },
1123 int fd_netlink = -1;
1125 struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
1126 struct udev_ctrl_connection *ctrl_conn = NULL;
1133 udev_log_init("udevd");
1134 udev_set_log_fn(udev, log_fn);
1135 info(udev, "version %s\n", VERSION);
1136 udev_selinux_init(udev);
1138 /* make sure, that our runtime dir exists and is writable */
1139 if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) < 0) {
1140 /* try to create our own subdirectory, do not create parent directories */
1141 mkdir(udev_get_run_config_path(udev), 0755);
1143 if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) >= 0) {
1144 /* directory seems writable now */
1145 udev_set_run_path(udev, udev_get_run_config_path(udev));
1147 /* fall back to /dev/.udev */
1148 char filename[UTIL_PATH_SIZE];
1150 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev", NULL);
1151 if (udev_set_run_path(udev, filename) == NULL)
1153 mkdir(udev_get_run_path(udev), 0755);
1156 /* relabel runtime dir only if it resides below /dev */
1157 if (strncmp(udev_get_run_path(udev), udev_get_dev_path(udev), strlen(udev_get_dev_path(udev))) == 0)
1158 udev_selinux_lsetfilecon(udev, udev_get_run_path(udev), 0755);
1159 info(udev, "runtime dir '%s'\n", udev_get_run_path(udev));
1164 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1173 children_max = strtoul(optarg, NULL, 0);
1176 exec_delay = strtoul(optarg, NULL, 0);
1180 if (udev_get_log_priority(udev) < LOG_INFO)
1181 udev_set_log_priority(udev, LOG_INFO);
1184 if (strcmp (optarg, "early") == 0) {
1186 } else if (strcmp (optarg, "late") == 0) {
1188 } else if (strcmp (optarg, "never") == 0) {
1191 fprintf(stderr, "resolve-names must be early, late or never\n");
1192 err(udev, "resolve-names must be early, late or never\n");
1197 printf("Usage: udevd OPTIONS\n"
1200 " --children-max=<maximum number of workers>\n"
1201 " --exec-delay=<seconds to wait before executing RUN=>\n"
1202 " --resolve-names=early|late|never\n"
1208 printf("%s\n", VERSION);
1216 * read the kernel commandline, in case we need to get into debug mode
1217 * udev.log-priority=<level> syslog priority
1218 * udev.children-max=<number of workers> events are fully serialized if set to 1
1221 f = fopen("/proc/cmdline", "r");
1225 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1228 pos = strstr(cmdline, "udev.log-priority=");
1230 pos += strlen("udev.log-priority=");
1231 udev_set_log_priority(udev, util_log_priority(pos));
1234 pos = strstr(cmdline, "udev.children-max=");
1236 pos += strlen("udev.children-max=");
1237 children_max = strtoul(pos, NULL, 0);
1240 pos = strstr(cmdline, "udev.exec-delay=");
1242 pos += strlen("udev.exec-delay=");
1243 exec_delay = strtoul(pos, NULL, 0);
1249 if (getuid() != 0) {
1250 fprintf(stderr, "root privileges required\n");
1251 err(udev, "root privileges required\n");
1255 /* set umask before creating any file/directory */
1259 /* create standard links, copy static nodes, create nodes from modules */
1260 static_dev_create(udev);
1261 static_dev_create_from_modules(udev);
1263 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1264 fd = open("/dev/null", O_RDWR);
1266 fprintf(stderr, "cannot open /dev/null\n");
1267 err(udev, "cannot open /dev/null\n");
1269 if (write(STDOUT_FILENO, 0, 0) < 0)
1270 dup2(fd, STDOUT_FILENO);
1271 if (write(STDERR_FILENO, 0, 0) < 0)
1272 dup2(fd, STDERR_FILENO);
1274 /* udevadm control socket */
1275 if (sd_listen_fds(true) == 1 && sd_is_socket(SD_LISTEN_FDS_START, AF_LOCAL, SOCK_SEQPACKET, -1))
1276 udev_ctrl = udev_ctrl_new_from_fd(udev, SD_LISTEN_FDS_START);
1278 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
1279 if (udev_ctrl == NULL) {
1280 fprintf(stderr, "error initializing udev control socket");
1281 err(udev, "error initializing udev control socket");
1285 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1286 fprintf(stderr, "error binding udev control socket\n");
1287 err(udev, "error binding udev control socket\n");
1291 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1293 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1294 if (monitor == NULL || udev_monitor_enable_receiving(monitor) < 0) {
1295 fprintf(stderr, "error initializing netlink socket\n");
1296 err(udev, "error initializing netlink socket\n");
1300 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1301 fd_netlink = udev_monitor_get_fd(monitor);
1311 err(udev, "fork of daemon failed: %m\n");
1319 sd_notify(1, "READY=1");
1322 fd_inotify = udev_watch_init(udev);
1323 if (fd_inotify < 0) {
1324 fprintf(stderr, "error initializing inotify\n");
1325 err(udev, "error initializing inotify\n");
1330 if (udev_get_rules_path(udev) != NULL) {
1331 inotify_add_watch(fd_inotify, udev_get_rules_path(udev),
1332 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1334 char filename[UTIL_PATH_SIZE];
1335 struct stat statbuf;
1337 inotify_add_watch(fd_inotify, LIBEXECDIR "/rules.d",
1338 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1339 inotify_add_watch(fd_inotify, SYSCONFDIR "/udev/rules.d",
1340 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1342 /* watch dynamic rules directory */
1343 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/rules.d", NULL);
1344 if (stat(filename, &statbuf) != 0) {
1345 util_create_path(udev, filename);
1346 mkdir(filename, 0755);
1348 inotify_add_watch(fd_inotify, filename,
1349 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1351 udev_watch_restore(udev);
1353 /* block and listen to all signals on signalfd */
1355 sigprocmask(SIG_SETMASK, &mask, &orig_sigmask);
1356 fd_signal = signalfd(-1, &mask, SFD_CLOEXEC);
1357 if (fd_signal < 0) {
1358 fprintf(stderr, "error getting signalfd\n");
1359 err(udev, "error getting signalfd\n");
1364 /* unnamed socket from workers to the main daemon */
1365 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1366 fprintf(stderr, "error getting socketpair\n");
1367 err(udev, "error getting socketpair\n");
1371 fd_worker = worker_watch[READ_END];
1373 rules = udev_rules_new(udev, resolve_names);
1374 if (rules == NULL) {
1375 err(udev, "error reading rules\n");
1379 udev_queue_export = udev_queue_export_new(udev);
1380 if (udev_queue_export == NULL) {
1381 err(udev, "error creating queue file\n");
1385 memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1386 ep_ctrl.events = EPOLLIN;
1387 ep_ctrl.data.fd = fd_ctrl;
1388 memset(&ep_inotify, 0, sizeof(struct epoll_event));
1389 ep_inotify.events = EPOLLIN;
1390 ep_inotify.data.fd = fd_inotify;
1391 memset(&ep_signal, 0, sizeof(struct epoll_event));
1392 ep_signal.events = EPOLLIN;
1393 ep_signal.data.fd = fd_signal;
1394 memset(&ep_netlink, 0, sizeof(struct epoll_event));
1395 ep_netlink.events = EPOLLIN;
1396 ep_netlink.data.fd = fd_netlink;
1397 memset(&ep_worker, 0, sizeof(struct epoll_event));
1398 ep_worker.events = EPOLLIN;
1399 ep_worker.data.fd = fd_worker;
1400 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1402 err(udev, "error creating epoll fd: %m\n");
1405 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1406 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1407 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1408 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1409 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1410 err(udev, "fail to add fds to epoll: %m\n");
1414 /* if needed, convert old database from earlier udev version */
1418 dup2(fd, STDIN_FILENO);
1419 dup2(fd, STDOUT_FILENO);
1420 dup2(fd, STDERR_FILENO);
1422 if (fd > STDERR_FILENO)
1425 /* set scheduling priority for the main daemon process */
1426 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
1430 f = fopen("/dev/kmsg", "w");
1432 fprintf(f, "<30>udev[%u]: starting version " VERSION "\n", getpid());
1436 fd = open("/proc/self/oom_score_adj", O_RDWR);
1438 /* Fallback to old interface */
1439 fd = open("/proc/self/oom_adj", O_RDWR);
1441 err(udev, "error disabling OOM: %m\n");
1443 /* OOM_DISABLE == -17 */
1444 write(fd, "-17", 3);
1448 write(fd, "-1000", 5);
1452 if (children_max <= 0) {
1453 int memsize = mem_size_mb();
1455 /* set value depending on the amount of RAM */
1457 children_max = 128 + (memsize / 8);
1461 info(udev, "set children_max to %u\n", children_max);
1463 udev_rules_apply_static_dev_perms(rules);
1465 udev_list_init(&event_list);
1466 udev_list_init(&worker_list);
1469 struct epoll_event ev[8];
1472 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1476 /* close sources of new events and discard buffered events */
1478 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1481 if (monitor != NULL) {
1482 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1483 udev_monitor_unref(monitor);
1486 if (fd_inotify >= 0) {
1487 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1492 /* discard queued events and kill workers */
1493 event_queue_cleanup(udev, EVENT_QUEUED);
1494 worker_kill(udev, 0);
1496 /* exit after all has cleaned up */
1497 if (udev_list_is_empty(&event_list) && udev_list_is_empty(&worker_list))
1500 /* timeout at exit for workers to finish */
1501 timeout = 60 * 1000;
1502 } else if (udev_list_is_empty(&event_list) && children > 2) {
1503 /* set timeout to kill idle workers */
1508 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
1514 info(udev, "timeout, giving up waiting for workers to finish\n");
1518 /* timeout - kill idle workers */
1519 worker_kill(udev, 2);
1522 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1523 for (i = 0; i < fdcount; i++) {
1524 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1526 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1528 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1530 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1532 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1536 /* event has finished */
1538 worker_returned(fd_worker);
1541 struct udev_device *dev;
1543 dev = udev_monitor_receive_device(monitor);
1545 if (event_queue_insert(dev) < 0)
1546 udev_device_unref(dev);
1549 /* start new events */
1550 if (!udev_list_is_empty(&event_list) && !udev_exit && !stop_exec_queue)
1551 event_queue_start(udev);
1554 struct signalfd_siginfo fdsi;
1557 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1558 if (size == sizeof(struct signalfd_siginfo))
1559 handle_signal(udev, fdsi.ssi_signo);
1562 /* we are shutting down, the events below are not handled anymore */
1566 /* device node and rules directory inotify watch */
1568 handle_inotify(udev);
1571 * This needs to be after the inotify handling, to make sure,
1572 * that the ping is send back after the possibly generated
1573 * "change" events by the inotify device node watch.
1575 * A single time we may receive a client connection which we need to
1576 * keep open to block the client. It will be closed right before we
1580 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1582 /* rules changed, set by inotify or a HUP signal */
1583 if (reload_config) {
1584 struct udev_rules *rules_new;
1586 worker_kill(udev, 0);
1587 rules_new = udev_rules_new(udev, resolve_names);
1588 if (rules_new != NULL) {
1589 udev_rules_unref(rules);
1596 udev_queue_export_cleanup(udev_queue_export);
1601 worker_list_cleanup(udev);
1602 event_queue_cleanup(udev, EVENT_UNDEF);
1603 udev_rules_unref(rules);
1606 if (worker_watch[READ_END] >= 0)
1607 close(worker_watch[READ_END]);
1608 if (worker_watch[WRITE_END] >= 0)
1609 close(worker_watch[WRITE_END]);
1610 udev_monitor_unref(monitor);
1611 udev_queue_export_unref(udev_queue_export);
1612 udev_ctrl_connection_unref(ctrl_conn);
1613 udev_ctrl_unref(udev_ctrl);
1614 udev_selinux_exit(udev);