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)
60 vsnprintf(buf, sizeof(buf), format, args);
61 clock_gettime(CLOCK_MONOTONIC, &ts);
62 fprintf(stderr, "%llu.%06u [%u] %s: %s",
63 (unsigned long long) ts.tv_sec, (unsigned int) ts.tv_nsec/1000,
64 (int) getpid(), fn, buf);
66 vsyslog(priority, format, args);
70 static struct udev_rules *rules;
71 static struct udev_queue_export *udev_queue_export;
72 static struct udev_ctrl *udev_ctrl;
73 static struct udev_monitor *monitor;
74 static int worker_watch[2] = { -1, -1 };
75 static int fd_signal = -1;
76 static int fd_ep = -1;
77 static int fd_inotify = -1;
78 static bool stop_exec_queue;
79 static bool reload_config;
81 static int children_max;
82 static int exec_delay;
83 static sigset_t sigmask_orig;
84 static UDEV_LIST(event_list);
85 static UDEV_LIST(worker_list);
86 static bool udev_exit;
95 struct udev_list_node node;
97 struct udev_device *dev;
98 enum event_state state;
100 unsigned long long int delaying_seqnum;
101 unsigned long long int seqnum;
104 const char *devpath_old;
110 static struct event *node_to_event(struct udev_list_node *node)
114 event = (char *)node;
115 event -= offsetof(struct event, node);
116 return (struct event *)event;
119 static void event_queue_cleanup(struct udev *udev, enum event_state type);
129 struct udev_list_node node;
133 struct udev_monitor *monitor;
134 enum worker_state state;
138 /* passed from worker to main process */
139 struct worker_message {
144 static struct worker *node_to_worker(struct udev_list_node *node)
148 worker = (char *)node;
149 worker -= offsetof(struct worker, node);
150 return (struct worker *)worker;
153 static void event_queue_delete(struct event *event, bool export)
155 udev_list_node_remove(&event->node);
158 /* mark as failed, if "add" event returns non-zero */
159 if (event->exitcode != 0 && strcmp(udev_device_get_action(event->dev), "remove") != 0)
160 udev_queue_export_device_failed(udev_queue_export, event->dev);
162 udev_queue_export_device_finished(udev_queue_export, event->dev);
163 info(event->udev, "seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
165 udev_device_unref(event->dev);
169 static struct worker *worker_ref(struct worker *worker)
175 static void worker_cleanup(struct worker *worker)
177 udev_list_node_remove(&worker->node);
178 udev_monitor_unref(worker->monitor);
183 static void worker_unref(struct worker *worker)
186 if (worker->refcount > 0)
188 info(worker->udev, "worker [%u] cleaned up\n", worker->pid);
189 worker_cleanup(worker);
192 static void worker_list_cleanup(struct udev *udev)
194 struct udev_list_node *loop, *tmp;
196 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
197 struct worker *worker = node_to_worker(loop);
199 worker_cleanup(worker);
203 static void worker_new(struct event *event)
205 struct udev *udev = event->udev;
206 struct worker *worker;
207 struct udev_monitor *worker_monitor;
210 /* listen for new events */
211 worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
212 if (worker_monitor == NULL)
214 /* allow the main daemon netlink address to send devices to the worker */
215 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
216 udev_monitor_enable_receiving(worker_monitor);
218 worker = calloc(1, sizeof(struct worker));
219 if (worker == NULL) {
220 udev_monitor_unref(worker_monitor);
223 /* worker + event reference */
224 worker->refcount = 2;
230 struct udev_device *dev = NULL;
232 struct epoll_event ep_signal, ep_monitor;
234 int rc = EXIT_SUCCESS;
236 /* move initial device from queue */
241 worker_list_cleanup(udev);
242 event_queue_cleanup(udev, EVENT_UNDEF);
243 udev_queue_export_unref(udev_queue_export);
244 udev_monitor_unref(monitor);
245 udev_ctrl_unref(udev_ctrl);
248 close(worker_watch[READ_END]);
251 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
253 err(udev, "error creating signalfd %m\n");
258 fd_ep = epoll_create1(EPOLL_CLOEXEC);
260 err(udev, "error creating epoll fd: %m\n");
265 memset(&ep_signal, 0, sizeof(struct epoll_event));
266 ep_signal.events = EPOLLIN;
267 ep_signal.data.fd = fd_signal;
269 fd_monitor = udev_monitor_get_fd(worker_monitor);
270 memset(&ep_monitor, 0, sizeof(struct epoll_event));
271 ep_monitor.events = EPOLLIN;
272 ep_monitor.data.fd = fd_monitor;
274 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
275 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
276 err(udev, "fail to add fds to epoll: %m\n");
281 /* request TERM signal if parent exits */
282 prctl(PR_SET_PDEATHSIG, SIGTERM);
285 struct udev_event *udev_event;
286 struct worker_message msg;
290 info(udev, "seq %llu running\n", udev_device_get_seqnum(dev));
291 udev_event = udev_event_new(dev);
292 if (udev_event == NULL) {
297 /* needed for SIGCHLD/SIGTERM in spawn() */
298 udev_event->fd_signal = fd_signal;
301 udev_event->exec_delay = exec_delay;
303 /* apply rules, create node, symlinks */
304 err = udev_event_execute_rules(udev_event, rules, &sigmask_orig);
307 failed = udev_event_execute_run(udev_event, &sigmask_orig);
309 /* apply/restore inotify watch */
310 if (err == 0 && udev_event->inotify_watch) {
311 udev_watch_begin(udev, dev);
312 udev_device_update_db(dev);
315 /* send processed event back to libudev listeners */
316 udev_monitor_send_device(worker_monitor, NULL, dev);
318 /* send udevd the result of the event execution */
319 memset(&msg, 0, sizeof(struct worker_message));
322 else if (failed != 0)
323 msg.exitcode = failed;
325 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
327 info(udev, "seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
329 udev_device_unref(dev);
332 if (udev_event->sigterm) {
333 udev_event_unref(udev_event);
337 udev_event_unref(udev_event);
339 /* wait for more device messages from main udevd, or term signal */
340 while (dev == NULL) {
341 struct epoll_event ev[4];
345 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), -1);
350 err(udev, "failed to poll: %m\n");
354 for (i = 0; i < fdcount; i++) {
355 if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
356 dev = udev_monitor_receive_device(worker_monitor);
357 } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
358 struct signalfd_siginfo fdsi;
361 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
362 if (size != sizeof(struct signalfd_siginfo))
364 switch (fdsi.ssi_signo) {
373 udev_device_unref(dev);
379 close(worker_watch[WRITE_END]);
380 udev_rules_unref(rules);
381 udev_monitor_unref(worker_monitor);
387 udev_monitor_unref(worker_monitor);
388 event->state = EVENT_QUEUED;
390 err(udev, "fork of child failed: %m\n");
393 /* close monitor, but keep address around */
394 udev_monitor_disconnect(worker_monitor);
395 worker->monitor = worker_monitor;
397 worker->state = WORKER_RUNNING;
398 worker->event = event;
399 event->state = EVENT_RUNNING;
400 udev_list_node_append(&worker->node, &worker_list);
402 info(udev, "seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
407 static void event_run(struct event *event, bool force)
409 struct udev_list_node *loop;
411 udev_list_node_foreach(loop, &worker_list) {
412 struct worker *worker = node_to_worker(loop);
415 if (worker->state != WORKER_IDLE)
418 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
420 err(event->udev, "worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
421 kill(worker->pid, SIGKILL);
422 worker->state = WORKER_KILLED;
426 worker->event = event;
427 worker->state = WORKER_RUNNING;
428 event->state = EVENT_RUNNING;
432 if (!force && children >= children_max) {
433 if (children_max > 1)
434 info(event->udev, "maximum number (%i) of children reached\n", children);
438 /* start new worker and pass initial device */
442 static int event_queue_insert(struct udev_device *dev)
446 event = calloc(1, sizeof(struct event));
450 event->udev = udev_device_get_udev(dev);
452 event->seqnum = udev_device_get_seqnum(dev);
453 event->devpath = udev_device_get_devpath(dev);
454 event->devpath_len = strlen(event->devpath);
455 event->devpath_old = udev_device_get_devpath_old(dev);
456 event->devnum = udev_device_get_devnum(dev);
457 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
458 event->ifindex = udev_device_get_ifindex(dev);
460 udev_queue_export_device_queued(udev_queue_export, dev);
461 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
462 udev_device_get_action(dev), udev_device_get_subsystem(dev));
464 event->state = EVENT_QUEUED;
465 udev_list_node_append(&event->node, &event_list);
467 /* run all events with a timeout set immediately */
468 if (udev_device_get_timeout(dev) > 0) {
469 event_run(event, true);
476 static void worker_kill(struct udev *udev, int retain)
478 struct udev_list_node *loop;
481 if (children <= retain)
484 max = children - retain;
486 udev_list_node_foreach(loop, &worker_list) {
487 struct worker *worker = node_to_worker(loop);
492 if (worker->state == WORKER_KILLED)
495 worker->state = WORKER_KILLED;
496 kill(worker->pid, SIGTERM);
500 /* lookup event for identical, parent, child device */
501 static bool is_devpath_busy(struct event *event)
503 struct udev_list_node *loop;
506 /* check if queue contains events we depend on */
507 udev_list_node_foreach(loop, &event_list) {
508 struct event *loop_event = node_to_event(loop);
510 /* we already found a later event, earlier can not block us, no need to check again */
511 if (loop_event->seqnum < event->delaying_seqnum)
514 /* event we checked earlier still exists, no need to check again */
515 if (loop_event->seqnum == event->delaying_seqnum)
518 /* found ourself, no later event can block us */
519 if (loop_event->seqnum >= event->seqnum)
522 /* check major/minor */
523 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
526 /* check network device ifindex */
527 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
530 /* check our old name */
531 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
532 event->delaying_seqnum = loop_event->seqnum;
536 /* compare devpath */
537 common = MIN(loop_event->devpath_len, event->devpath_len);
539 /* one devpath is contained in the other? */
540 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
543 /* identical device event found */
544 if (loop_event->devpath_len == event->devpath_len) {
545 /* devices names might have changed/swapped in the meantime */
546 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
548 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
550 event->delaying_seqnum = loop_event->seqnum;
554 /* parent device event found */
555 if (event->devpath[common] == '/') {
556 event->delaying_seqnum = loop_event->seqnum;
560 /* child device event found */
561 if (loop_event->devpath[common] == '/') {
562 event->delaying_seqnum = loop_event->seqnum;
566 /* no matching device */
573 static void event_queue_start(struct udev *udev)
575 struct udev_list_node *loop;
577 udev_list_node_foreach(loop, &event_list) {
578 struct event *event = node_to_event(loop);
580 if (event->state != EVENT_QUEUED)
583 /* do not start event if parent or child event is still running */
584 if (is_devpath_busy(event)) {
585 dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath);
589 event_run(event, false);
593 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
595 struct udev_list_node *loop, *tmp;
597 udev_list_node_foreach_safe(loop, tmp, &event_list) {
598 struct event *event = node_to_event(loop);
600 if (match_type != EVENT_UNDEF && match_type != event->state)
603 event_queue_delete(event, false);
607 static void worker_returned(int fd_worker)
610 struct worker_message msg;
612 struct udev_list_node *loop;
614 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
615 if (size != sizeof(struct worker_message))
618 /* lookup worker who sent the signal */
619 udev_list_node_foreach(loop, &worker_list) {
620 struct worker *worker = node_to_worker(loop);
622 if (worker->pid != msg.pid)
625 /* worker returned */
626 worker->event->exitcode = msg.exitcode;
627 event_queue_delete(worker->event, true);
628 worker->event = NULL;
629 if (worker->state != WORKER_KILLED)
630 worker->state = WORKER_IDLE;
631 worker_unref(worker);
637 /* receive the udevd message from userspace */
638 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
640 struct udev *udev = udev_ctrl_get_udev(uctrl);
641 struct udev_ctrl_connection *ctrl_conn;
642 struct udev_ctrl_msg *ctrl_msg = NULL;
646 ctrl_conn = udev_ctrl_get_connection(uctrl);
647 if (ctrl_conn == NULL)
650 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
651 if (ctrl_msg == NULL)
654 i = udev_ctrl_get_set_log_level(ctrl_msg);
656 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
657 udev_set_log_priority(udev, i);
658 worker_kill(udev, 0);
661 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
662 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
663 stop_exec_queue = true;
666 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
667 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
668 stop_exec_queue = false;
671 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
672 info(udev, "udevd message (RELOAD_RULES) received\n");
673 reload_config = true;
676 str = udev_ctrl_get_set_env(ctrl_msg);
684 val = strchr(key, '=');
688 if (val[0] == '\0') {
689 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
690 udev_add_property(udev, key, NULL);
692 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
693 udev_add_property(udev, key, val);
696 err(udev, "wrong key format '%s'\n", key);
700 worker_kill(udev, 0);
703 i = udev_ctrl_get_set_children_max(ctrl_msg);
705 info(udev, "udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
709 if (udev_ctrl_get_ping(ctrl_msg) > 0)
710 info(udev, "udevd message (SYNC) received\n");
712 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
713 info(udev, "udevd message (EXIT) received\n");
715 /* keep reference to block the client until we exit */
716 udev_ctrl_connection_ref(ctrl_conn);
719 udev_ctrl_msg_unref(ctrl_msg);
720 return udev_ctrl_connection_unref(ctrl_conn);
723 /* read inotify messages */
724 static int handle_inotify(struct udev *udev)
728 struct inotify_event *ev;
730 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
733 buf = malloc(nbytes);
735 err(udev, "error getting buffer for inotify\n");
739 nbytes = read(fd_inotify, buf, nbytes);
741 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
742 struct udev_device *dev;
744 ev = (struct inotify_event *)(buf + pos);
748 info(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
749 s = strstr(ev->name, ".rules");
752 if (strlen(s) != strlen(".rules"))
754 reload_config = true;
758 dev = udev_watch_lookup(udev, ev->wd);
760 info(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
761 if (ev->mask & IN_CLOSE_WRITE) {
762 char filename[UTIL_PATH_SIZE];
765 info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
766 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
767 fd = open(filename, O_WRONLY);
769 if (write(fd, "change", 6) < 0)
770 info(udev, "error writing uevent: %m\n");
774 if (ev->mask & IN_IGNORED)
775 udev_watch_end(udev, dev);
777 udev_device_unref(dev);
786 static void handle_signal(struct udev *udev, int signo)
797 struct udev_list_node *loop, *tmp;
799 pid = waitpid(-1, &status, WNOHANG);
803 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
804 struct worker *worker = node_to_worker(loop);
806 if (worker->pid != pid)
808 info(udev, "worker [%u] exit\n", pid);
810 if (WIFEXITED(status)) {
811 if (WEXITSTATUS(status) != 0)
812 err(udev, "worker [%u] exit with return code %i\n", pid, WEXITSTATUS(status));
813 } else if (WIFSIGNALED(status)) {
814 err(udev, "worker [%u] terminated by signal %i (%s)\n",
815 pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
816 } else if (WIFSTOPPED(status)) {
817 err(udev, "worker [%u] stopped\n", pid);
818 } else if (WIFCONTINUED(status)) {
819 err(udev, "worker [%u] continued\n", pid);
821 err(udev, "worker [%u] exit with status 0x%04x\n", pid, status);
824 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
825 if (worker->event != NULL) {
826 err(udev, "worker [%u] failed while handling '%s'\n",
827 pid, worker->event->devpath);
828 worker->event->exitcode = -32;
829 event_queue_delete(worker->event, true);
830 /* drop reference taken for state 'running' */
831 worker_unref(worker);
834 worker_unref(worker);
840 reload_config = true;
845 static void static_dev_create_from_modules(struct udev *udev)
847 struct utsname kernel;
848 char modules[UTIL_PATH_SIZE];
853 util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
854 f = fopen(modules, "r");
858 while (fgets(buf, sizeof(buf), f) != NULL) {
866 char filename[UTIL_PATH_SIZE];
872 s = strchr(modname, ' ');
878 s = strchr(devname, ' ');
884 s = strchr(devno, ' ');
886 s = strchr(devno, '\n');
889 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
893 mode = 0600 | S_IFCHR;
894 else if (type == 'b')
895 mode = 0600 | S_IFBLK;
899 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
900 util_create_path_selinux(udev, filename);
901 udev_selinux_setfscreatecon(udev, filename, mode);
902 info(udev, "mknod '%s' %c%u:%u\n", filename, type, maj, min);
903 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
904 utimensat(AT_FDCWD, filename, NULL, 0);
905 udev_selinux_resetfscreatecon(udev);
911 static int copy_dev_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
915 for (dent = readdir(dir_from); dent != NULL; dent = readdir(dir_from)) {
918 if (dent->d_name[0] == '.')
920 if (fstatat(dirfd(dir_from), dent->d_name, &stats, AT_SYMLINK_NOFOLLOW) != 0)
923 if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
924 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, stats.st_mode & 0777);
925 if (mknodat(dirfd(dir_to), dent->d_name, stats.st_mode, stats.st_rdev) == 0) {
926 fchmodat(dirfd(dir_to), dent->d_name, stats.st_mode & 0777, 0);
927 fchownat(dirfd(dir_to), dent->d_name, stats.st_uid, stats.st_gid, 0);
929 utimensat(dirfd(dir_to), dent->d_name, NULL, 0);
931 udev_selinux_resetfscreatecon(udev);
932 } else if (S_ISLNK(stats.st_mode)) {
933 char target[UTIL_PATH_SIZE];
936 len = readlinkat(dirfd(dir_from), dent->d_name, target, sizeof(target));
937 if (len <= 0 || len == (ssize_t)sizeof(target))
940 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFLNK);
941 if (symlinkat(target, dirfd(dir_to), dent->d_name) < 0 && errno == EEXIST)
942 utimensat(dirfd(dir_to), dent->d_name, NULL, AT_SYMLINK_NOFOLLOW);
943 udev_selinux_resetfscreatecon(udev);
944 } else if (S_ISDIR(stats.st_mode)) {
945 DIR *dir2_from, *dir2_to;
950 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFDIR|0755);
951 mkdirat(dirfd(dir_to), dent->d_name, 0755);
952 udev_selinux_resetfscreatecon(udev);
954 dir2_to = fdopendir(openat(dirfd(dir_to), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
958 dir2_from = fdopendir(openat(dirfd(dir_from), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
959 if (dir2_from == NULL) {
964 copy_dev_dir(udev, dir2_from, dir2_to, maxdepth-1);
974 static void static_dev_create_links(struct udev *udev, DIR *dir)
980 static const struct stdlinks stdlinks[] = {
981 { "core", "/proc/kcore" },
982 { "fd", "/proc/self/fd" },
983 { "stdin", "/proc/self/fd/0" },
984 { "stdout", "/proc/self/fd/1" },
985 { "stderr", "/proc/self/fd/2" },
989 for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
992 if (stat(stdlinks[i].target, &sb) == 0) {
993 udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
994 if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
995 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
996 udev_selinux_resetfscreatecon(udev);
1001 static void static_dev_create_from_devices(struct udev *udev, DIR *dir)
1005 dir_from = opendir(LIBEXECDIR "/devices");
1006 if (dir_from == NULL)
1008 copy_dev_dir(udev, dir_from, dir, 8);
1012 static void static_dev_create(struct udev *udev)
1016 dir = opendir(udev_get_dev_path(udev));
1020 static_dev_create_links(udev, dir);
1021 static_dev_create_from_devices(udev, dir);
1026 static int mem_size_mb(void)
1030 long int memsize = -1;
1032 f = fopen("/proc/meminfo", "r");
1036 while (fgets(buf, sizeof(buf), f) != NULL) {
1039 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
1040 memsize = value / 1024;
1049 static int convert_db(struct udev *udev)
1051 char filename[UTIL_PATH_SIZE];
1053 struct udev_enumerate *udev_enumerate;
1054 struct udev_list_entry *list_entry;
1056 /* current database */
1057 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/data", NULL);
1058 if (access(filename, F_OK) >= 0)
1061 /* make sure we do not get here again */
1062 util_create_path(udev, filename);
1063 mkdir(filename, 0755);
1066 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/db", NULL);
1067 if (access(filename, F_OK) < 0)
1070 f = fopen("/dev/kmsg", "w");
1072 fprintf(f, "<30>udevd[%u]: converting old udev database\n", getpid());
1076 udev_enumerate = udev_enumerate_new(udev);
1077 if (udev_enumerate == NULL)
1079 udev_enumerate_scan_devices(udev_enumerate);
1080 udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
1081 struct udev_device *device;
1083 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
1087 /* try to find the old database for devices without a current one */
1088 if (udev_device_read_db(device, NULL) < 0) {
1092 char devpath[UTIL_PATH_SIZE];
1093 char from[UTIL_PATH_SIZE];
1097 /* find database in old location */
1098 id = udev_device_get_id_filename(device);
1099 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
1100 if (lstat(from, &stats) == 0) {
1102 udev_device_read_db(device, from);
1108 /* find old database with $subsys:$sysname name */
1109 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
1110 "/.udev/db/", udev_device_get_subsystem(device), ":",
1111 udev_device_get_sysname(device), NULL);
1112 if (lstat(from, &stats) == 0) {
1114 udev_device_read_db(device, from);
1120 /* find old database with the encoded devpath name */
1121 util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
1122 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", devpath, NULL);
1123 if (lstat(from, &stats) == 0) {
1125 udev_device_read_db(device, from);
1131 /* write out new database */
1133 udev_device_update_db(device);
1135 udev_device_unref(device);
1137 udev_enumerate_unref(udev_enumerate);
1141 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
1143 int ctrl = -1, netlink = -1;
1146 n = sd_listen_fds(true);
1150 for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
1151 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
1158 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
1168 if (ctrl < 0 || netlink < 0)
1171 info(udev, "ctrl=%i netlink=%i\n", ctrl, netlink);
1173 *rnetlink = netlink;
1177 int main(int argc, char *argv[])
1182 int daemonize = false;
1183 int resolve_names = 1;
1184 static const struct option options[] = {
1185 { "daemon", no_argument, NULL, 'd' },
1186 { "debug", no_argument, NULL, 'D' },
1187 { "children-max", required_argument, NULL, 'c' },
1188 { "exec-delay", required_argument, NULL, 'e' },
1189 { "resolve-names", required_argument, NULL, 'N' },
1190 { "help", no_argument, NULL, 'h' },
1191 { "version", no_argument, NULL, 'V' },
1195 int fd_netlink = -1;
1197 struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
1198 struct udev_ctrl_connection *ctrl_conn = NULL;
1205 udev_log_init("udevd");
1206 udev_set_log_fn(udev, log_fn);
1207 info(udev, "version %s\n", VERSION);
1208 udev_selinux_init(udev);
1210 /* make sure, that our runtime dir exists and is writable */
1211 if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) < 0) {
1212 /* try to create our own subdirectory, do not create parent directories */
1213 mkdir(udev_get_run_config_path(udev), 0755);
1215 if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) >= 0) {
1216 /* directory seems writable now */
1217 udev_set_run_path(udev, udev_get_run_config_path(udev));
1219 /* fall back to /dev/.udev */
1220 char filename[UTIL_PATH_SIZE];
1222 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev", NULL);
1223 if (udev_set_run_path(udev, filename) == NULL)
1225 mkdir(udev_get_run_path(udev), 0755);
1226 err(udev, "error: runtime directory '%s' not writable, for now falling back to '%s'",
1227 udev_get_run_config_path(udev), udev_get_run_path(udev));
1230 /* relabel runtime dir only if it resides below /dev */
1231 if (strncmp(udev_get_run_path(udev), udev_get_dev_path(udev), strlen(udev_get_dev_path(udev))) == 0)
1232 udev_selinux_lsetfilecon(udev, udev_get_run_path(udev), 0755);
1233 info(udev, "runtime dir '%s'\n", udev_get_run_path(udev));
1238 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1247 children_max = strtoul(optarg, NULL, 0);
1250 exec_delay = strtoul(optarg, NULL, 0);
1254 if (udev_get_log_priority(udev) < LOG_INFO)
1255 udev_set_log_priority(udev, LOG_INFO);
1258 if (strcmp (optarg, "early") == 0) {
1260 } else if (strcmp (optarg, "late") == 0) {
1262 } else if (strcmp (optarg, "never") == 0) {
1265 fprintf(stderr, "resolve-names must be early, late or never\n");
1266 err(udev, "resolve-names must be early, late or never\n");
1271 printf("Usage: udevd OPTIONS\n"
1274 " --children-max=<maximum number of workers>\n"
1275 " --exec-delay=<seconds to wait before executing RUN=>\n"
1276 " --resolve-names=early|late|never\n"
1282 printf("%s\n", VERSION);
1290 * read the kernel commandline, in case we need to get into debug mode
1291 * udev.log-priority=<level> syslog priority
1292 * udev.children-max=<number of workers> events are fully serialized if set to 1
1295 f = fopen("/proc/cmdline", "r");
1299 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1302 pos = strstr(cmdline, "udev.log-priority=");
1304 pos += strlen("udev.log-priority=");
1305 udev_set_log_priority(udev, util_log_priority(pos));
1308 pos = strstr(cmdline, "udev.children-max=");
1310 pos += strlen("udev.children-max=");
1311 children_max = strtoul(pos, NULL, 0);
1314 pos = strstr(cmdline, "udev.exec-delay=");
1316 pos += strlen("udev.exec-delay=");
1317 exec_delay = strtoul(pos, NULL, 0);
1323 if (getuid() != 0) {
1324 fprintf(stderr, "root privileges required\n");
1325 err(udev, "root privileges required\n");
1329 /* set umask before creating any file/directory */
1333 /* create standard links, copy static nodes, create nodes from modules */
1334 static_dev_create(udev);
1335 static_dev_create_from_modules(udev);
1337 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1341 fd = open("/dev/null", O_RDWR);
1343 if (write(STDOUT_FILENO, 0, 0) < 0)
1344 dup2(fd, STDOUT_FILENO);
1345 if (write(STDERR_FILENO, 0, 0) < 0)
1346 dup2(fd, STDERR_FILENO);
1347 if (fd > STDERR_FILENO)
1350 fprintf(stderr, "cannot open /dev/null\n");
1351 err(udev, "cannot open /dev/null\n");
1355 if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1356 /* get control and netlink socket from from systemd */
1357 udev_ctrl = udev_ctrl_new_from_socket_fd(udev, UDEV_CTRL_SOCK_PATH, fd_ctrl);
1358 if (udev_ctrl == NULL) {
1359 err(udev, "error taking over udev control socket");
1364 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1365 if (monitor == NULL) {
1366 err(udev, "error taking over netlink socket\n");
1371 /* open control and netlink socket */
1372 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
1373 if (udev_ctrl == NULL) {
1374 fprintf(stderr, "error initializing udev control socket");
1375 err(udev, "error initializing udev control socket");
1379 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1381 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1382 if (monitor == NULL) {
1383 fprintf(stderr, "error initializing netlink socket\n");
1384 err(udev, "error initializing netlink socket\n");
1388 fd_netlink = udev_monitor_get_fd(monitor);
1391 if (udev_monitor_enable_receiving(monitor) < 0) {
1392 fprintf(stderr, "error binding netlink socket\n");
1393 err(udev, "error binding netlink socket\n");
1398 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1399 fprintf(stderr, "error binding udev control socket\n");
1400 err(udev, "error binding udev control socket\n");
1405 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1407 /* create queue file before signalling 'ready', to make sure we block 'settle' */
1408 udev_queue_export = udev_queue_export_new(udev);
1409 if (udev_queue_export == NULL) {
1410 err(udev, "error creating queue file\n");
1423 err(udev, "fork of daemon failed: %m\n");
1428 goto exit_keep_queue;
1433 fd = open("/proc/self/oom_score_adj", O_RDWR);
1435 /* Fallback to old interface */
1436 fd = open("/proc/self/oom_adj", O_RDWR);
1438 err(udev, "error disabling OOM: %m\n");
1440 /* OOM_DISABLE == -17 */
1441 write(fd, "-17", 3);
1445 write(fd, "-1000", 5);
1449 sd_notify(1, "READY=1");
1452 f = fopen("/dev/kmsg", "w");
1454 fprintf(f, "<30>udevd[%u]: starting version " VERSION "\n", getpid());
1461 fd = open("/dev/null", O_RDWR);
1463 dup2(fd, STDIN_FILENO);
1464 dup2(fd, STDOUT_FILENO);
1465 dup2(fd, STDERR_FILENO);
1470 fd_inotify = udev_watch_init(udev);
1471 if (fd_inotify < 0) {
1472 fprintf(stderr, "error initializing inotify\n");
1473 err(udev, "error initializing inotify\n");
1478 if (udev_get_rules_path(udev) != NULL) {
1479 inotify_add_watch(fd_inotify, udev_get_rules_path(udev),
1480 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1482 char filename[UTIL_PATH_SIZE];
1483 struct stat statbuf;
1485 inotify_add_watch(fd_inotify, LIBEXECDIR "/rules.d",
1486 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1487 inotify_add_watch(fd_inotify, SYSCONFDIR "/udev/rules.d",
1488 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1490 /* watch dynamic rules directory */
1491 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/rules.d", NULL);
1492 if (stat(filename, &statbuf) != 0) {
1493 util_create_path(udev, filename);
1494 mkdir(filename, 0755);
1496 inotify_add_watch(fd_inotify, filename,
1497 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1499 udev_watch_restore(udev);
1501 /* block and listen to all signals on signalfd */
1503 sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1504 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1505 if (fd_signal < 0) {
1506 fprintf(stderr, "error creating signalfd\n");
1507 err(udev, "error creating signalfd\n");
1512 /* unnamed socket from workers to the main daemon */
1513 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1514 fprintf(stderr, "error creating socketpair\n");
1515 err(udev, "error creating socketpair\n");
1519 fd_worker = worker_watch[READ_END];
1521 rules = udev_rules_new(udev, resolve_names);
1522 if (rules == NULL) {
1523 err(udev, "error reading rules\n");
1527 memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1528 ep_ctrl.events = EPOLLIN;
1529 ep_ctrl.data.fd = fd_ctrl;
1531 memset(&ep_inotify, 0, sizeof(struct epoll_event));
1532 ep_inotify.events = EPOLLIN;
1533 ep_inotify.data.fd = fd_inotify;
1535 memset(&ep_signal, 0, sizeof(struct epoll_event));
1536 ep_signal.events = EPOLLIN;
1537 ep_signal.data.fd = fd_signal;
1539 memset(&ep_netlink, 0, sizeof(struct epoll_event));
1540 ep_netlink.events = EPOLLIN;
1541 ep_netlink.data.fd = fd_netlink;
1543 memset(&ep_worker, 0, sizeof(struct epoll_event));
1544 ep_worker.events = EPOLLIN;
1545 ep_worker.data.fd = fd_worker;
1547 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1549 err(udev, "error creating epoll fd: %m\n");
1552 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1553 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1554 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1555 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1556 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1557 err(udev, "fail to add fds to epoll: %m\n");
1561 /* if needed, convert old database from earlier udev version */
1564 if (children_max <= 0) {
1565 int memsize = mem_size_mb();
1567 /* set value depending on the amount of RAM */
1569 children_max = 128 + (memsize / 8);
1573 info(udev, "set children_max to %u\n", children_max);
1575 udev_rules_apply_static_dev_perms(rules);
1577 udev_list_init(&event_list);
1578 udev_list_init(&worker_list);
1581 struct epoll_event ev[8];
1584 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1588 /* close sources of new events and discard buffered events */
1590 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1593 if (monitor != NULL) {
1594 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1595 udev_monitor_unref(monitor);
1598 if (fd_inotify >= 0) {
1599 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1604 /* discard queued events and kill workers */
1605 event_queue_cleanup(udev, EVENT_QUEUED);
1606 worker_kill(udev, 0);
1608 /* exit after all has cleaned up */
1609 if (udev_list_is_empty(&event_list) && udev_list_is_empty(&worker_list))
1612 /* timeout at exit for workers to finish */
1613 timeout = 60 * 1000;
1614 } else if (udev_list_is_empty(&event_list) && children > 2) {
1615 /* set timeout to kill idle workers */
1620 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
1626 info(udev, "timeout, giving up waiting for workers to finish\n");
1630 /* timeout - kill idle workers */
1631 worker_kill(udev, 2);
1634 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1635 for (i = 0; i < fdcount; i++) {
1636 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1638 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1640 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1642 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1644 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1648 /* event has finished */
1650 worker_returned(fd_worker);
1653 struct udev_device *dev;
1655 dev = udev_monitor_receive_device(monitor);
1657 if (event_queue_insert(dev) < 0)
1658 udev_device_unref(dev);
1661 /* start new events */
1662 if (!udev_list_is_empty(&event_list) && !udev_exit && !stop_exec_queue)
1663 event_queue_start(udev);
1666 struct signalfd_siginfo fdsi;
1669 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1670 if (size == sizeof(struct signalfd_siginfo))
1671 handle_signal(udev, fdsi.ssi_signo);
1674 /* we are shutting down, the events below are not handled anymore */
1678 /* device node and rules directory inotify watch */
1680 handle_inotify(udev);
1683 * This needs to be after the inotify handling, to make sure,
1684 * that the ping is send back after the possibly generated
1685 * "change" events by the inotify device node watch.
1687 * A single time we may receive a client connection which we need to
1688 * keep open to block the client. It will be closed right before we
1692 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1694 /* rules changed, set by inotify or a HUP signal */
1695 if (reload_config) {
1696 struct udev_rules *rules_new;
1698 worker_kill(udev, 0);
1699 rules_new = udev_rules_new(udev, resolve_names);
1700 if (rules_new != NULL) {
1701 udev_rules_unref(rules);
1710 udev_queue_export_cleanup(udev_queue_export);
1714 worker_list_cleanup(udev);
1715 event_queue_cleanup(udev, EVENT_UNDEF);
1716 udev_rules_unref(rules);
1719 if (worker_watch[READ_END] >= 0)
1720 close(worker_watch[READ_END]);
1721 if (worker_watch[WRITE_END] >= 0)
1722 close(worker_watch[WRITE_END]);
1723 udev_monitor_unref(monitor);
1724 udev_queue_export_unref(udev_queue_export);
1725 udev_ctrl_connection_unref(ctrl_conn);
1726 udev_ctrl_unref(udev_ctrl);
1727 udev_selinux_exit(udev);