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"
52 static void log_fn(struct udev *udev, int priority,
53 const char *file, int line, const char *fn,
54 const char *format, va_list args)
61 vsnprintf(buf, sizeof(buf), format, args);
62 gettimeofday(&tv, &tz);
63 fprintf(stderr, "%llu.%06u [%u] %s: %s",
64 (unsigned long long) tv.tv_sec, (unsigned int) tv.tv_usec,
65 (int) getpid(), fn, buf);
67 vsyslog(priority, format, args);
71 static struct udev_rules *rules;
72 static struct udev_queue_export *udev_queue_export;
73 static struct udev_ctrl *udev_ctrl;
74 static struct udev_monitor *monitor;
75 static int worker_watch[2] = { -1, -1 };
76 static int fd_signal = -1;
77 static int fd_ep = -1;
78 static int fd_inotify = -1;
79 static bool stop_exec_queue;
80 static bool reload_config;
82 static int children_max;
83 static int exec_delay;
84 static sigset_t sigmask_orig;
85 static UDEV_LIST(event_list);
86 static UDEV_LIST(worker_list);
87 static bool udev_exit;
96 struct udev_list_node node;
98 struct udev_device *dev;
99 enum event_state state;
101 unsigned long long int delaying_seqnum;
102 unsigned long long int seqnum;
105 const char *devpath_old;
111 static struct event *node_to_event(struct udev_list_node *node)
115 event = (char *)node;
116 event -= offsetof(struct event, node);
117 return (struct event *)event;
120 static void event_queue_cleanup(struct udev *udev, enum event_state type);
130 struct udev_list_node node;
134 struct udev_monitor *monitor;
135 enum worker_state state;
139 /* passed from worker to main process */
140 struct worker_message {
145 static struct worker *node_to_worker(struct udev_list_node *node)
149 worker = (char *)node;
150 worker -= offsetof(struct worker, node);
151 return (struct worker *)worker;
154 static void event_queue_delete(struct event *event, bool export)
156 udev_list_node_remove(&event->node);
159 /* mark as failed, if "add" event returns non-zero */
160 if (event->exitcode != 0 && strcmp(udev_device_get_action(event->dev), "remove") != 0)
161 udev_queue_export_device_failed(udev_queue_export, event->dev);
163 udev_queue_export_device_finished(udev_queue_export, event->dev);
164 info(event->udev, "seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
166 udev_device_unref(event->dev);
170 static struct worker *worker_ref(struct worker *worker)
176 static void worker_cleanup(struct worker *worker)
178 udev_list_node_remove(&worker->node);
179 udev_monitor_unref(worker->monitor);
184 static void worker_unref(struct worker *worker)
187 if (worker->refcount > 0)
189 info(worker->udev, "worker [%u] cleaned up\n", worker->pid);
190 worker_cleanup(worker);
193 static void worker_list_cleanup(struct udev *udev)
195 struct udev_list_node *loop, *tmp;
197 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
198 struct worker *worker = node_to_worker(loop);
200 worker_cleanup(worker);
204 static void worker_new(struct event *event)
206 struct udev *udev = event->udev;
207 struct worker *worker;
208 struct udev_monitor *worker_monitor;
211 /* listen for new events */
212 worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
213 if (worker_monitor == NULL)
215 /* allow the main daemon netlink address to send devices to the worker */
216 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
217 udev_monitor_enable_receiving(worker_monitor);
219 worker = calloc(1, sizeof(struct worker));
220 if (worker == NULL) {
221 udev_monitor_unref(worker_monitor);
224 /* worker + event reference */
225 worker->refcount = 2;
231 struct udev_device *dev = NULL;
233 struct epoll_event ep_signal, ep_monitor;
235 int rc = EXIT_SUCCESS;
237 /* move initial device from queue */
242 worker_list_cleanup(udev);
243 event_queue_cleanup(udev, EVENT_UNDEF);
244 udev_queue_export_unref(udev_queue_export);
245 udev_monitor_unref(monitor);
246 udev_ctrl_unref(udev_ctrl);
249 close(worker_watch[READ_END]);
252 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
254 err(udev, "error creating signalfd %m\n");
259 fd_ep = epoll_create1(EPOLL_CLOEXEC);
261 err(udev, "error creating epoll fd: %m\n");
266 memset(&ep_signal, 0, sizeof(struct epoll_event));
267 ep_signal.events = EPOLLIN;
268 ep_signal.data.fd = fd_signal;
270 fd_monitor = udev_monitor_get_fd(worker_monitor);
271 memset(&ep_monitor, 0, sizeof(struct epoll_event));
272 ep_monitor.events = EPOLLIN;
273 ep_monitor.data.fd = fd_monitor;
275 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
276 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
277 err(udev, "fail to add fds to epoll: %m\n");
282 /* request TERM signal if parent exits */
283 prctl(PR_SET_PDEATHSIG, SIGTERM);
286 struct udev_event *udev_event;
287 struct worker_message msg;
291 info(udev, "seq %llu running\n", udev_device_get_seqnum(dev));
292 udev_event = udev_event_new(dev);
293 if (udev_event == NULL) {
298 /* needed for SIGCHLD/SIGTERM in spawn() */
299 udev_event->fd_signal = fd_signal;
302 udev_event->exec_delay = exec_delay;
304 /* apply rules, create node, symlinks */
305 err = udev_event_execute_rules(udev_event, rules, &sigmask_orig);
308 failed = udev_event_execute_run(udev_event, &sigmask_orig);
310 /* apply/restore inotify watch */
311 if (err == 0 && udev_event->inotify_watch) {
312 udev_watch_begin(udev, dev);
313 udev_device_update_db(dev);
316 /* send processed event back to libudev listeners */
317 udev_monitor_send_device(worker_monitor, NULL, dev);
319 /* send udevd the result of the event execution */
320 memset(&msg, 0, sizeof(struct worker_message));
323 else if (failed != 0)
324 msg.exitcode = failed;
326 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
328 info(udev, "seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
330 udev_device_unref(dev);
333 if (udev_event->sigterm) {
334 udev_event_unref(udev_event);
338 udev_event_unref(udev_event);
340 /* wait for more device messages from main udevd, or term signal */
341 while (dev == NULL) {
342 struct epoll_event ev[4];
346 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), -1);
351 err(udev, "failed to poll: %m\n");
355 for (i = 0; i < fdcount; i++) {
356 if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
357 dev = udev_monitor_receive_device(worker_monitor);
358 } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
359 struct signalfd_siginfo fdsi;
362 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
363 if (size != sizeof(struct signalfd_siginfo))
365 switch (fdsi.ssi_signo) {
374 udev_device_unref(dev);
380 close(worker_watch[WRITE_END]);
381 udev_rules_unref(rules);
382 udev_monitor_unref(worker_monitor);
388 udev_monitor_unref(worker_monitor);
389 event->state = EVENT_QUEUED;
391 err(udev, "fork of child failed: %m\n");
394 /* close monitor, but keep address around */
395 udev_monitor_disconnect(worker_monitor);
396 worker->monitor = worker_monitor;
398 worker->state = WORKER_RUNNING;
399 worker->event = event;
400 event->state = EVENT_RUNNING;
401 udev_list_node_append(&worker->node, &worker_list);
403 info(udev, "seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
408 static void event_run(struct event *event, bool force)
410 struct udev_list_node *loop;
412 udev_list_node_foreach(loop, &worker_list) {
413 struct worker *worker = node_to_worker(loop);
416 if (worker->state != WORKER_IDLE)
419 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
421 err(event->udev, "worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
422 kill(worker->pid, SIGKILL);
423 worker->state = WORKER_KILLED;
427 worker->event = event;
428 worker->state = WORKER_RUNNING;
429 event->state = EVENT_RUNNING;
433 if (!force && children >= children_max) {
434 if (children_max > 1)
435 info(event->udev, "maximum number (%i) of children reached\n", children);
439 /* start new worker and pass initial device */
443 static int event_queue_insert(struct udev_device *dev)
447 event = calloc(1, sizeof(struct event));
451 event->udev = udev_device_get_udev(dev);
453 event->seqnum = udev_device_get_seqnum(dev);
454 event->devpath = udev_device_get_devpath(dev);
455 event->devpath_len = strlen(event->devpath);
456 event->devpath_old = udev_device_get_devpath_old(dev);
457 event->devnum = udev_device_get_devnum(dev);
458 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
459 event->ifindex = udev_device_get_ifindex(dev);
461 udev_queue_export_device_queued(udev_queue_export, dev);
462 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
463 udev_device_get_action(dev), udev_device_get_subsystem(dev));
465 event->state = EVENT_QUEUED;
466 udev_list_node_append(&event->node, &event_list);
468 /* run all events with a timeout set immediately */
469 if (udev_device_get_timeout(dev) > 0) {
470 event_run(event, true);
477 static void worker_kill(struct udev *udev, int retain)
479 struct udev_list_node *loop;
482 if (children <= retain)
485 max = children - retain;
487 udev_list_node_foreach(loop, &worker_list) {
488 struct worker *worker = node_to_worker(loop);
493 if (worker->state == WORKER_KILLED)
496 worker->state = WORKER_KILLED;
497 kill(worker->pid, SIGTERM);
501 /* lookup event for identical, parent, child device */
502 static bool is_devpath_busy(struct event *event)
504 struct udev_list_node *loop;
507 /* check if queue contains events we depend on */
508 udev_list_node_foreach(loop, &event_list) {
509 struct event *loop_event = node_to_event(loop);
511 /* we already found a later event, earlier can not block us, no need to check again */
512 if (loop_event->seqnum < event->delaying_seqnum)
515 /* event we checked earlier still exists, no need to check again */
516 if (loop_event->seqnum == event->delaying_seqnum)
519 /* found ourself, no later event can block us */
520 if (loop_event->seqnum >= event->seqnum)
523 /* check major/minor */
524 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
527 /* check network device ifindex */
528 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
531 /* check our old name */
532 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
533 event->delaying_seqnum = loop_event->seqnum;
537 /* compare devpath */
538 common = MIN(loop_event->devpath_len, event->devpath_len);
540 /* one devpath is contained in the other? */
541 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
544 /* identical device event found */
545 if (loop_event->devpath_len == event->devpath_len) {
546 /* devices names might have changed/swapped in the meantime */
547 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
549 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
551 event->delaying_seqnum = loop_event->seqnum;
555 /* parent device event found */
556 if (event->devpath[common] == '/') {
557 event->delaying_seqnum = loop_event->seqnum;
561 /* child device event found */
562 if (loop_event->devpath[common] == '/') {
563 event->delaying_seqnum = loop_event->seqnum;
567 /* no matching device */
574 static void event_queue_start(struct udev *udev)
576 struct udev_list_node *loop;
578 udev_list_node_foreach(loop, &event_list) {
579 struct event *event = node_to_event(loop);
581 if (event->state != EVENT_QUEUED)
584 /* do not start event if parent or child event is still running */
585 if (is_devpath_busy(event)) {
586 dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath);
590 event_run(event, false);
594 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
596 struct udev_list_node *loop, *tmp;
598 udev_list_node_foreach_safe(loop, tmp, &event_list) {
599 struct event *event = node_to_event(loop);
601 if (match_type != EVENT_UNDEF && match_type != event->state)
604 event_queue_delete(event, false);
608 static void worker_returned(int fd_worker)
611 struct worker_message msg;
613 struct udev_list_node *loop;
615 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
616 if (size != sizeof(struct worker_message))
619 /* lookup worker who sent the signal */
620 udev_list_node_foreach(loop, &worker_list) {
621 struct worker *worker = node_to_worker(loop);
623 if (worker->pid != msg.pid)
626 /* worker returned */
627 worker->event->exitcode = msg.exitcode;
628 event_queue_delete(worker->event, true);
629 worker->event = NULL;
630 if (worker->state != WORKER_KILLED)
631 worker->state = WORKER_IDLE;
632 worker_unref(worker);
638 /* receive the udevd message from userspace */
639 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
641 struct udev *udev = udev_ctrl_get_udev(uctrl);
642 struct udev_ctrl_connection *ctrl_conn;
643 struct udev_ctrl_msg *ctrl_msg = NULL;
647 ctrl_conn = udev_ctrl_get_connection(uctrl);
648 if (ctrl_conn == NULL)
651 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
652 if (ctrl_msg == NULL)
655 i = udev_ctrl_get_set_log_level(ctrl_msg);
657 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
658 udev_set_log_priority(udev, i);
659 worker_kill(udev, 0);
662 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
663 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
664 stop_exec_queue = true;
667 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
668 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
669 stop_exec_queue = false;
672 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
673 info(udev, "udevd message (RELOAD_RULES) received\n");
674 reload_config = true;
677 str = udev_ctrl_get_set_env(ctrl_msg);
685 val = strchr(key, '=');
689 if (val[0] == '\0') {
690 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
691 udev_add_property(udev, key, NULL);
693 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
694 udev_add_property(udev, key, val);
697 err(udev, "wrong key format '%s'\n", key);
701 worker_kill(udev, 0);
704 i = udev_ctrl_get_set_children_max(ctrl_msg);
706 info(udev, "udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
710 if (udev_ctrl_get_ping(ctrl_msg) > 0)
711 info(udev, "udevd message (SYNC) received\n");
713 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
714 info(udev, "udevd message (EXIT) received\n");
716 /* keep reference to block the client until we exit */
717 udev_ctrl_connection_ref(ctrl_conn);
720 udev_ctrl_msg_unref(ctrl_msg);
721 return udev_ctrl_connection_unref(ctrl_conn);
724 /* read inotify messages */
725 static int handle_inotify(struct udev *udev)
729 struct inotify_event *ev;
731 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
734 buf = malloc(nbytes);
736 err(udev, "error getting buffer for inotify\n");
740 nbytes = read(fd_inotify, buf, nbytes);
742 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
743 struct udev_device *dev;
745 ev = (struct inotify_event *)(buf + pos);
749 info(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
750 s = strstr(ev->name, ".rules");
753 if (strlen(s) != strlen(".rules"))
755 reload_config = true;
759 dev = udev_watch_lookup(udev, ev->wd);
761 info(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
762 if (ev->mask & IN_CLOSE_WRITE) {
763 char filename[UTIL_PATH_SIZE];
766 info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
767 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
768 fd = open(filename, O_WRONLY);
770 if (write(fd, "change", 6) < 0)
771 info(udev, "error writing uevent: %m\n");
775 if (ev->mask & IN_IGNORED)
776 udev_watch_end(udev, dev);
778 udev_device_unref(dev);
787 static void handle_signal(struct udev *udev, int signo)
798 struct udev_list_node *loop, *tmp;
800 pid = waitpid(-1, &status, WNOHANG);
804 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
805 struct worker *worker = node_to_worker(loop);
807 if (worker->pid != pid)
809 info(udev, "worker [%u] exit\n", pid);
811 if (WIFEXITED(status)) {
812 if (WEXITSTATUS(status) != 0)
813 err(udev, "worker [%u] exit with return code %i\n", pid, WEXITSTATUS(status));
814 } else if (WIFSIGNALED(status)) {
815 err(udev, "worker [%u] terminated by signal %i (%s)\n",
816 pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
817 } else if (WIFSTOPPED(status)) {
818 err(udev, "worker [%u] stopped\n", pid);
819 } else if (WIFCONTINUED(status)) {
820 err(udev, "worker [%u] continued\n", pid);
822 err(udev, "worker [%u] exit with status 0x%04x\n", pid, status);
825 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
826 if (worker->event != NULL) {
827 err(udev, "worker [%u] failed while handling '%s'\n",
828 pid, worker->event->devpath);
829 worker->event->exitcode = -32;
830 event_queue_delete(worker->event, true);
831 /* drop reference taken for state 'running' */
832 worker_unref(worker);
835 worker_unref(worker);
841 reload_config = true;
846 static void static_dev_create_from_modules(struct udev *udev)
848 struct utsname kernel;
849 char modules[UTIL_PATH_SIZE];
854 util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
855 f = fopen(modules, "r");
859 while (fgets(buf, sizeof(buf), f) != NULL) {
867 char filename[UTIL_PATH_SIZE];
873 s = strchr(modname, ' ');
879 s = strchr(devname, ' ');
885 s = strchr(devno, ' ');
887 s = strchr(devno, '\n');
890 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
894 mode = 0600 | S_IFCHR;
895 else if (type == 'b')
896 mode = 0600 | S_IFBLK;
900 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
901 util_create_path_selinux(udev, filename);
902 udev_selinux_setfscreatecon(udev, filename, mode);
903 info(udev, "mknod '%s' %c%u:%u\n", filename, type, maj, min);
904 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
905 utimensat(AT_FDCWD, filename, NULL, 0);
906 udev_selinux_resetfscreatecon(udev);
912 static int copy_dev_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
916 for (dent = readdir(dir_from); dent != NULL; dent = readdir(dir_from)) {
919 if (dent->d_name[0] == '.')
921 if (fstatat(dirfd(dir_from), dent->d_name, &stats, AT_SYMLINK_NOFOLLOW) != 0)
924 if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
925 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, stats.st_mode & 0777);
926 if (mknodat(dirfd(dir_to), dent->d_name, stats.st_mode, stats.st_rdev) == 0) {
927 fchmodat(dirfd(dir_to), dent->d_name, stats.st_mode & 0777, 0);
928 fchownat(dirfd(dir_to), dent->d_name, stats.st_uid, stats.st_gid, 0);
930 utimensat(dirfd(dir_to), dent->d_name, NULL, 0);
932 udev_selinux_resetfscreatecon(udev);
933 } else if (S_ISLNK(stats.st_mode)) {
934 char target[UTIL_PATH_SIZE];
937 len = readlinkat(dirfd(dir_from), dent->d_name, target, sizeof(target));
938 if (len <= 0 || len == (ssize_t)sizeof(target))
941 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFLNK);
942 if (symlinkat(target, dirfd(dir_to), dent->d_name) < 0 && errno == EEXIST)
943 utimensat(dirfd(dir_to), dent->d_name, NULL, AT_SYMLINK_NOFOLLOW);
944 udev_selinux_resetfscreatecon(udev);
945 } else if (S_ISDIR(stats.st_mode)) {
946 DIR *dir2_from, *dir2_to;
951 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFDIR|0755);
952 mkdirat(dirfd(dir_to), dent->d_name, 0755);
953 udev_selinux_resetfscreatecon(udev);
955 dir2_to = fdopendir(openat(dirfd(dir_to), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
959 dir2_from = fdopendir(openat(dirfd(dir_from), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
960 if (dir2_from == NULL) {
965 copy_dev_dir(udev, dir2_from, dir2_to, maxdepth-1);
975 static void static_dev_create_links(struct udev *udev, DIR *dir)
981 static const struct stdlinks stdlinks[] = {
982 { "core", "/proc/kcore" },
983 { "fd", "/proc/self/fd" },
984 { "stdin", "/proc/self/fd/0" },
985 { "stdout", "/proc/self/fd/1" },
986 { "stderr", "/proc/self/fd/2" },
990 for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
993 if (stat(stdlinks[i].target, &sb) == 0) {
994 udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
995 if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
996 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
997 udev_selinux_resetfscreatecon(udev);
1002 static void static_dev_create_from_devices(struct udev *udev, DIR *dir)
1006 dir_from = opendir(LIBEXECDIR "/devices");
1007 if (dir_from == NULL)
1009 copy_dev_dir(udev, dir_from, dir, 8);
1013 static void static_dev_create(struct udev *udev)
1017 dir = opendir(udev_get_dev_path(udev));
1021 static_dev_create_links(udev, dir);
1022 static_dev_create_from_devices(udev, dir);
1027 static int mem_size_mb(void)
1031 long int memsize = -1;
1033 f = fopen("/proc/meminfo", "r");
1037 while (fgets(buf, sizeof(buf), f) != NULL) {
1040 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
1041 memsize = value / 1024;
1050 static int convert_db(struct udev *udev)
1052 char filename[UTIL_PATH_SIZE];
1054 struct udev_enumerate *udev_enumerate;
1055 struct udev_list_entry *list_entry;
1057 /* current database */
1058 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/data", NULL);
1059 if (access(filename, F_OK) >= 0)
1062 /* make sure we do not get here again */
1063 util_create_path(udev, filename);
1064 mkdir(filename, 0755);
1067 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/db", NULL);
1068 if (access(filename, F_OK) < 0)
1071 f = fopen("/dev/kmsg", "w");
1073 fprintf(f, "<30>udevd[%u]: converting old udev database\n", getpid());
1077 udev_enumerate = udev_enumerate_new(udev);
1078 if (udev_enumerate == NULL)
1080 udev_enumerate_scan_devices(udev_enumerate);
1081 udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
1082 struct udev_device *device;
1084 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
1088 /* try to find the old database for devices without a current one */
1089 if (udev_device_read_db(device, NULL) < 0) {
1093 char devpath[UTIL_PATH_SIZE];
1094 char from[UTIL_PATH_SIZE];
1098 /* find database in old location */
1099 id = udev_device_get_id_filename(device);
1100 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
1101 if (lstat(from, &stats) == 0) {
1103 udev_device_read_db(device, from);
1109 /* find old database with $subsys:$sysname name */
1110 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
1111 "/.udev/db/", udev_device_get_subsystem(device), ":",
1112 udev_device_get_sysname(device), NULL);
1113 if (lstat(from, &stats) == 0) {
1115 udev_device_read_db(device, from);
1121 /* find old database with the encoded devpath name */
1122 util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
1123 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", devpath, NULL);
1124 if (lstat(from, &stats) == 0) {
1126 udev_device_read_db(device, from);
1132 /* write out new database */
1134 udev_device_update_db(device);
1136 udev_device_unref(device);
1138 udev_enumerate_unref(udev_enumerate);
1142 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
1144 int ctrl = -1, netlink = -1;
1147 n = sd_listen_fds(true);
1151 for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
1152 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
1159 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
1169 if (ctrl < 0 || netlink < 0)
1172 info(udev, "ctrl=%i netlink=%i\n", ctrl, netlink);
1174 *rnetlink = netlink;
1178 int main(int argc, char *argv[])
1183 int daemonize = false;
1184 int resolve_names = 1;
1185 static const struct option options[] = {
1186 { "daemon", no_argument, NULL, 'd' },
1187 { "debug", no_argument, NULL, 'D' },
1188 { "children-max", required_argument, NULL, 'c' },
1189 { "exec-delay", required_argument, NULL, 'e' },
1190 { "resolve-names", required_argument, NULL, 'N' },
1191 { "help", no_argument, NULL, 'h' },
1192 { "version", no_argument, NULL, 'V' },
1196 int fd_netlink = -1;
1198 struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
1199 struct udev_ctrl_connection *ctrl_conn = NULL;
1206 udev_log_init("udevd");
1207 udev_set_log_fn(udev, log_fn);
1208 info(udev, "version %s\n", VERSION);
1209 udev_selinux_init(udev);
1211 /* make sure, that our runtime dir exists and is writable */
1212 if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) < 0) {
1213 /* try to create our own subdirectory, do not create parent directories */
1214 mkdir(udev_get_run_config_path(udev), 0755);
1216 if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) >= 0) {
1217 /* directory seems writable now */
1218 udev_set_run_path(udev, udev_get_run_config_path(udev));
1220 /* fall back to /dev/.udev */
1221 char filename[UTIL_PATH_SIZE];
1223 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev", NULL);
1224 if (udev_set_run_path(udev, filename) == NULL)
1226 mkdir(udev_get_run_path(udev), 0755);
1227 err(udev, "error: runtime directory '%s' not writable, for now falling back to '%s'",
1228 udev_get_run_config_path(udev), udev_get_run_path(udev));
1231 /* relabel runtime dir only if it resides below /dev */
1232 if (strncmp(udev_get_run_path(udev), udev_get_dev_path(udev), strlen(udev_get_dev_path(udev))) == 0)
1233 udev_selinux_lsetfilecon(udev, udev_get_run_path(udev), 0755);
1234 info(udev, "runtime dir '%s'\n", udev_get_run_path(udev));
1239 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1248 children_max = strtoul(optarg, NULL, 0);
1251 exec_delay = strtoul(optarg, NULL, 0);
1255 if (udev_get_log_priority(udev) < LOG_INFO)
1256 udev_set_log_priority(udev, LOG_INFO);
1259 if (strcmp (optarg, "early") == 0) {
1261 } else if (strcmp (optarg, "late") == 0) {
1263 } else if (strcmp (optarg, "never") == 0) {
1266 fprintf(stderr, "resolve-names must be early, late or never\n");
1267 err(udev, "resolve-names must be early, late or never\n");
1272 printf("Usage: udevd OPTIONS\n"
1275 " --children-max=<maximum number of workers>\n"
1276 " --exec-delay=<seconds to wait before executing RUN=>\n"
1277 " --resolve-names=early|late|never\n"
1283 printf("%s\n", VERSION);
1291 * read the kernel commandline, in case we need to get into debug mode
1292 * udev.log-priority=<level> syslog priority
1293 * udev.children-max=<number of workers> events are fully serialized if set to 1
1296 f = fopen("/proc/cmdline", "r");
1300 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1303 pos = strstr(cmdline, "udev.log-priority=");
1305 pos += strlen("udev.log-priority=");
1306 udev_set_log_priority(udev, util_log_priority(pos));
1309 pos = strstr(cmdline, "udev.children-max=");
1311 pos += strlen("udev.children-max=");
1312 children_max = strtoul(pos, NULL, 0);
1315 pos = strstr(cmdline, "udev.exec-delay=");
1317 pos += strlen("udev.exec-delay=");
1318 exec_delay = strtoul(pos, NULL, 0);
1324 if (getuid() != 0) {
1325 fprintf(stderr, "root privileges required\n");
1326 err(udev, "root privileges required\n");
1330 /* set umask before creating any file/directory */
1334 /* create standard links, copy static nodes, create nodes from modules */
1335 static_dev_create(udev);
1336 static_dev_create_from_modules(udev);
1338 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1342 fd = open("/dev/null", O_RDWR);
1344 if (write(STDOUT_FILENO, 0, 0) < 0)
1345 dup2(fd, STDOUT_FILENO);
1346 if (write(STDERR_FILENO, 0, 0) < 0)
1347 dup2(fd, STDERR_FILENO);
1348 if (fd > STDERR_FILENO)
1351 fprintf(stderr, "cannot open /dev/null\n");
1352 err(udev, "cannot open /dev/null\n");
1356 if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1357 /* get control and netlink socket from from systemd */
1358 udev_ctrl = udev_ctrl_new_from_socket_fd(udev, UDEV_CTRL_SOCK_PATH, fd_ctrl);
1359 if (udev_ctrl == NULL) {
1360 err(udev, "error taking over udev control socket");
1365 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1366 if (monitor == NULL) {
1367 err(udev, "error taking over netlink socket\n");
1372 /* open control and netlink socket */
1373 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
1374 if (udev_ctrl == NULL) {
1375 fprintf(stderr, "error initializing udev control socket");
1376 err(udev, "error initializing udev control socket");
1380 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1382 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1383 if (monitor == NULL) {
1384 fprintf(stderr, "error initializing netlink socket\n");
1385 err(udev, "error initializing netlink socket\n");
1389 fd_netlink = udev_monitor_get_fd(monitor);
1392 if (udev_monitor_enable_receiving(monitor) < 0) {
1393 fprintf(stderr, "error binding netlink socket\n");
1394 err(udev, "error binding netlink socket\n");
1399 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1400 fprintf(stderr, "error binding udev control socket\n");
1401 err(udev, "error binding udev control socket\n");
1406 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1408 /* create queue file before signalling 'ready', to make sure we block 'settle' */
1409 udev_queue_export = udev_queue_export_new(udev);
1410 if (udev_queue_export == NULL) {
1411 err(udev, "error creating queue file\n");
1424 err(udev, "fork of daemon failed: %m\n");
1429 goto exit_keep_queue;
1434 fd = open("/proc/self/oom_score_adj", O_RDWR);
1436 /* Fallback to old interface */
1437 fd = open("/proc/self/oom_adj", O_RDWR);
1439 err(udev, "error disabling OOM: %m\n");
1441 /* OOM_DISABLE == -17 */
1442 write(fd, "-17", 3);
1446 write(fd, "-1000", 5);
1450 sd_notify(1, "READY=1");
1453 f = fopen("/dev/kmsg", "w");
1455 fprintf(f, "<30>udevd[%u]: starting version " VERSION "\n", getpid());
1462 fd = open("/dev/null", O_RDWR);
1464 dup2(fd, STDIN_FILENO);
1465 dup2(fd, STDOUT_FILENO);
1466 dup2(fd, STDERR_FILENO);
1471 fd_inotify = udev_watch_init(udev);
1472 if (fd_inotify < 0) {
1473 fprintf(stderr, "error initializing inotify\n");
1474 err(udev, "error initializing inotify\n");
1479 if (udev_get_rules_path(udev) != NULL) {
1480 inotify_add_watch(fd_inotify, udev_get_rules_path(udev),
1481 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1483 char filename[UTIL_PATH_SIZE];
1484 struct stat statbuf;
1486 inotify_add_watch(fd_inotify, LIBEXECDIR "/rules.d",
1487 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1488 inotify_add_watch(fd_inotify, SYSCONFDIR "/udev/rules.d",
1489 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1491 /* watch dynamic rules directory */
1492 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/rules.d", NULL);
1493 if (stat(filename, &statbuf) != 0) {
1494 util_create_path(udev, filename);
1495 mkdir(filename, 0755);
1497 inotify_add_watch(fd_inotify, filename,
1498 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1500 udev_watch_restore(udev);
1502 /* block and listen to all signals on signalfd */
1504 sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1505 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1506 if (fd_signal < 0) {
1507 fprintf(stderr, "error creating signalfd\n");
1508 err(udev, "error creating signalfd\n");
1513 /* unnamed socket from workers to the main daemon */
1514 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1515 fprintf(stderr, "error creating socketpair\n");
1516 err(udev, "error creating socketpair\n");
1520 fd_worker = worker_watch[READ_END];
1522 rules = udev_rules_new(udev, resolve_names);
1523 if (rules == NULL) {
1524 err(udev, "error reading rules\n");
1528 memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1529 ep_ctrl.events = EPOLLIN;
1530 ep_ctrl.data.fd = fd_ctrl;
1532 memset(&ep_inotify, 0, sizeof(struct epoll_event));
1533 ep_inotify.events = EPOLLIN;
1534 ep_inotify.data.fd = fd_inotify;
1536 memset(&ep_signal, 0, sizeof(struct epoll_event));
1537 ep_signal.events = EPOLLIN;
1538 ep_signal.data.fd = fd_signal;
1540 memset(&ep_netlink, 0, sizeof(struct epoll_event));
1541 ep_netlink.events = EPOLLIN;
1542 ep_netlink.data.fd = fd_netlink;
1544 memset(&ep_worker, 0, sizeof(struct epoll_event));
1545 ep_worker.events = EPOLLIN;
1546 ep_worker.data.fd = fd_worker;
1548 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1550 err(udev, "error creating epoll fd: %m\n");
1553 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1554 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1555 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1556 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1557 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1558 err(udev, "fail to add fds to epoll: %m\n");
1562 /* if needed, convert old database from earlier udev version */
1565 if (children_max <= 0) {
1566 int memsize = mem_size_mb();
1568 /* set value depending on the amount of RAM */
1570 children_max = 128 + (memsize / 8);
1574 info(udev, "set children_max to %u\n", children_max);
1576 udev_rules_apply_static_dev_perms(rules);
1578 udev_list_init(&event_list);
1579 udev_list_init(&worker_list);
1582 struct epoll_event ev[8];
1585 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1589 /* close sources of new events and discard buffered events */
1591 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1594 if (monitor != NULL) {
1595 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1596 udev_monitor_unref(monitor);
1599 if (fd_inotify >= 0) {
1600 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1605 /* discard queued events and kill workers */
1606 event_queue_cleanup(udev, EVENT_QUEUED);
1607 worker_kill(udev, 0);
1609 /* exit after all has cleaned up */
1610 if (udev_list_is_empty(&event_list) && udev_list_is_empty(&worker_list))
1613 /* timeout at exit for workers to finish */
1614 timeout = 60 * 1000;
1615 } else if (udev_list_is_empty(&event_list) && children > 2) {
1616 /* set timeout to kill idle workers */
1621 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
1627 info(udev, "timeout, giving up waiting for workers to finish\n");
1631 /* timeout - kill idle workers */
1632 worker_kill(udev, 2);
1635 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1636 for (i = 0; i < fdcount; i++) {
1637 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1639 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1641 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1643 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1645 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1649 /* event has finished */
1651 worker_returned(fd_worker);
1654 struct udev_device *dev;
1656 dev = udev_monitor_receive_device(monitor);
1658 if (event_queue_insert(dev) < 0)
1659 udev_device_unref(dev);
1662 /* start new events */
1663 if (!udev_list_is_empty(&event_list) && !udev_exit && !stop_exec_queue)
1664 event_queue_start(udev);
1667 struct signalfd_siginfo fdsi;
1670 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1671 if (size == sizeof(struct signalfd_siginfo))
1672 handle_signal(udev, fdsi.ssi_signo);
1675 /* we are shutting down, the events below are not handled anymore */
1679 /* device node and rules directory inotify watch */
1681 handle_inotify(udev);
1684 * This needs to be after the inotify handling, to make sure,
1685 * that the ping is send back after the possibly generated
1686 * "change" events by the inotify device node watch.
1688 * A single time we may receive a client connection which we need to
1689 * keep open to block the client. It will be closed right before we
1693 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1695 /* rules changed, set by inotify or a HUP signal */
1696 if (reload_config) {
1697 struct udev_rules *rules_new;
1699 worker_kill(udev, 0);
1700 rules_new = udev_rules_new(udev, resolve_names);
1701 if (rules_new != NULL) {
1702 udev_rules_unref(rules);
1711 udev_queue_export_cleanup(udev_queue_export);
1715 worker_list_cleanup(udev);
1716 event_queue_cleanup(udev, EVENT_UNDEF);
1717 udev_rules_unref(rules);
1720 if (worker_watch[READ_END] >= 0)
1721 close(worker_watch[READ_END]);
1722 if (worker_watch[WRITE_END] >= 0)
1723 close(worker_watch[WRITE_END]);
1724 udev_monitor_unref(monitor);
1725 udev_queue_export_unref(udev_queue_export);
1726 udev_ctrl_connection_unref(ctrl_conn);
1727 udev_ctrl_unref(udev_ctrl);
1728 udev_selinux_exit(udev);