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 void udev_main_log(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;
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;
136 unsigned long long event_start_usec;
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 udev_queue_export_device_finished(udev_queue_export, event->dev);
160 info(event->udev, "seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
162 udev_device_unref(event->dev);
166 static struct worker *worker_ref(struct worker *worker)
172 static void worker_cleanup(struct worker *worker)
174 udev_list_node_remove(&worker->node);
175 udev_monitor_unref(worker->monitor);
180 static void worker_unref(struct worker *worker)
183 if (worker->refcount > 0)
185 info(worker->udev, "worker [%u] cleaned up\n", worker->pid);
186 worker_cleanup(worker);
189 static void worker_list_cleanup(struct udev *udev)
191 struct udev_list_node *loop, *tmp;
193 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
194 struct worker *worker = node_to_worker(loop);
196 worker_cleanup(worker);
200 static void worker_new(struct event *event)
202 struct udev *udev = event->udev;
203 struct worker *worker;
204 struct udev_monitor *worker_monitor;
207 /* listen for new events */
208 worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
209 if (worker_monitor == NULL)
211 /* allow the main daemon netlink address to send devices to the worker */
212 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
213 udev_monitor_enable_receiving(worker_monitor);
215 worker = calloc(1, sizeof(struct worker));
216 if (worker == NULL) {
217 udev_monitor_unref(worker_monitor);
220 /* worker + event reference */
221 worker->refcount = 2;
227 struct udev_device *dev = NULL;
229 struct epoll_event ep_signal, ep_monitor;
231 int rc = EXIT_SUCCESS;
233 /* take initial device from queue */
238 worker_list_cleanup(udev);
239 event_queue_cleanup(udev, EVENT_UNDEF);
240 udev_queue_export_unref(udev_queue_export);
241 udev_monitor_unref(monitor);
242 udev_ctrl_unref(udev_ctrl);
245 close(worker_watch[READ_END]);
248 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
250 err(udev, "error creating signalfd %m\n");
255 fd_ep = epoll_create1(EPOLL_CLOEXEC);
257 err(udev, "error creating epoll fd: %m\n");
262 memset(&ep_signal, 0, sizeof(struct epoll_event));
263 ep_signal.events = EPOLLIN;
264 ep_signal.data.fd = fd_signal;
266 fd_monitor = udev_monitor_get_fd(worker_monitor);
267 memset(&ep_monitor, 0, sizeof(struct epoll_event));
268 ep_monitor.events = EPOLLIN;
269 ep_monitor.data.fd = fd_monitor;
271 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
272 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
273 err(udev, "fail to add fds to epoll: %m\n");
278 /* request TERM signal if parent exits */
279 prctl(PR_SET_PDEATHSIG, SIGTERM);
282 struct udev_event *udev_event;
283 struct worker_message msg;
286 info(udev, "seq %llu running\n", udev_device_get_seqnum(dev));
287 udev_event = udev_event_new(dev);
288 if (udev_event == NULL) {
293 /* needed for SIGCHLD/SIGTERM in spawn() */
294 udev_event->fd_signal = fd_signal;
297 udev_event->exec_delay = exec_delay;
299 /* apply rules, create node, symlinks */
300 err = udev_event_execute_rules(udev_event, rules, &sigmask_orig);
303 udev_event_execute_run(udev_event, &sigmask_orig);
305 /* apply/restore inotify watch */
306 if (err == 0 && udev_event->inotify_watch) {
307 udev_watch_begin(udev, dev);
308 udev_device_update_db(dev);
311 /* send processed event back to libudev listeners */
312 udev_monitor_send_device(worker_monitor, NULL, dev);
314 /* send udevd the result of the event execution */
315 memset(&msg, 0, sizeof(struct worker_message));
319 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
321 info(udev, "seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
323 udev_device_unref(dev);
326 if (udev_event->sigterm) {
327 udev_event_unref(udev_event);
331 udev_event_unref(udev_event);
333 /* wait for more device messages from main udevd, or term signal */
334 while (dev == NULL) {
335 struct epoll_event ev[4];
339 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), -1);
344 err(udev, "failed to poll: %m\n");
348 for (i = 0; i < fdcount; i++) {
349 if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
350 dev = udev_monitor_receive_device(worker_monitor);
352 } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
353 struct signalfd_siginfo fdsi;
356 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
357 if (size != sizeof(struct signalfd_siginfo))
359 switch (fdsi.ssi_signo) {
368 udev_device_unref(dev);
374 close(worker_watch[WRITE_END]);
375 udev_rules_unref(rules);
376 udev_builtin_exit(udev);
377 udev_monitor_unref(worker_monitor);
383 udev_monitor_unref(worker_monitor);
384 event->state = EVENT_QUEUED;
386 err(udev, "fork of child failed: %m\n");
389 /* close monitor, but keep address around */
390 udev_monitor_disconnect(worker_monitor);
391 worker->monitor = worker_monitor;
393 worker->state = WORKER_RUNNING;
394 worker->event_start_usec = now_usec();
395 worker->event = event;
396 event->state = EVENT_RUNNING;
397 udev_list_node_append(&worker->node, &worker_list);
399 info(udev, "seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
404 static void event_run(struct event *event)
406 struct udev_list_node *loop;
408 udev_list_node_foreach(loop, &worker_list) {
409 struct worker *worker = node_to_worker(loop);
412 if (worker->state != WORKER_IDLE)
415 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
417 err(event->udev, "worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
418 kill(worker->pid, SIGKILL);
419 worker->state = WORKER_KILLED;
423 worker->event = event;
424 worker->state = WORKER_RUNNING;
425 worker->event_start_usec = now_usec();
426 event->state = EVENT_RUNNING;
430 if (children >= children_max) {
431 if (children_max > 1)
432 info(event->udev, "maximum number (%i) of children reached\n", children);
436 /* start new worker and pass initial device */
440 static int event_queue_insert(struct udev_device *dev)
444 event = calloc(1, sizeof(struct event));
448 event->udev = udev_device_get_udev(dev);
450 event->seqnum = udev_device_get_seqnum(dev);
451 event->devpath = udev_device_get_devpath(dev);
452 event->devpath_len = strlen(event->devpath);
453 event->devpath_old = udev_device_get_devpath_old(dev);
454 event->devnum = udev_device_get_devnum(dev);
455 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
456 event->ifindex = udev_device_get_ifindex(dev);
458 udev_queue_export_device_queued(udev_queue_export, dev);
459 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
460 udev_device_get_action(dev), udev_device_get_subsystem(dev));
462 event->state = EVENT_QUEUED;
463 udev_list_node_append(&event->node, &event_list);
467 static void worker_kill(struct udev *udev, int retain)
469 struct udev_list_node *loop;
472 if (children <= retain)
475 max = children - retain;
477 udev_list_node_foreach(loop, &worker_list) {
478 struct worker *worker = node_to_worker(loop);
483 if (worker->state == WORKER_KILLED)
486 worker->state = WORKER_KILLED;
487 kill(worker->pid, SIGTERM);
491 /* lookup event for identical, parent, child device */
492 static bool is_devpath_busy(struct event *event)
494 struct udev_list_node *loop;
497 /* check if queue contains events we depend on */
498 udev_list_node_foreach(loop, &event_list) {
499 struct event *loop_event = node_to_event(loop);
501 /* we already found a later event, earlier can not block us, no need to check again */
502 if (loop_event->seqnum < event->delaying_seqnum)
505 /* event we checked earlier still exists, no need to check again */
506 if (loop_event->seqnum == event->delaying_seqnum)
509 /* found ourself, no later event can block us */
510 if (loop_event->seqnum >= event->seqnum)
513 /* check major/minor */
514 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
517 /* check network device ifindex */
518 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
521 /* check our old name */
522 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
523 event->delaying_seqnum = loop_event->seqnum;
527 /* compare devpath */
528 common = MIN(loop_event->devpath_len, event->devpath_len);
530 /* one devpath is contained in the other? */
531 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
534 /* identical device event found */
535 if (loop_event->devpath_len == event->devpath_len) {
536 /* devices names might have changed/swapped in the meantime */
537 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
539 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
541 event->delaying_seqnum = loop_event->seqnum;
545 /* parent device event found */
546 if (event->devpath[common] == '/') {
547 event->delaying_seqnum = loop_event->seqnum;
551 /* child device event found */
552 if (loop_event->devpath[common] == '/') {
553 event->delaying_seqnum = loop_event->seqnum;
557 /* no matching device */
564 static void event_queue_start(struct udev *udev)
566 struct udev_list_node *loop;
568 udev_list_node_foreach(loop, &event_list) {
569 struct event *event = node_to_event(loop);
571 if (event->state != EVENT_QUEUED)
574 /* do not start event if parent or child event is still running */
575 if (is_devpath_busy(event)) {
576 dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath);
584 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
586 struct udev_list_node *loop, *tmp;
588 udev_list_node_foreach_safe(loop, tmp, &event_list) {
589 struct event *event = node_to_event(loop);
591 if (match_type != EVENT_UNDEF && match_type != event->state)
594 event_queue_delete(event, false);
598 static void worker_returned(int fd_worker)
601 struct worker_message msg;
603 struct udev_list_node *loop;
605 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
606 if (size != sizeof(struct worker_message))
609 /* lookup worker who sent the signal */
610 udev_list_node_foreach(loop, &worker_list) {
611 struct worker *worker = node_to_worker(loop);
613 if (worker->pid != msg.pid)
616 /* worker returned */
618 worker->event->exitcode = msg.exitcode;
619 event_queue_delete(worker->event, true);
620 worker->event = NULL;
622 if (worker->state != WORKER_KILLED)
623 worker->state = WORKER_IDLE;
624 worker_unref(worker);
630 /* receive the udevd message from userspace */
631 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
633 struct udev *udev = udev_ctrl_get_udev(uctrl);
634 struct udev_ctrl_connection *ctrl_conn;
635 struct udev_ctrl_msg *ctrl_msg = NULL;
639 ctrl_conn = udev_ctrl_get_connection(uctrl);
640 if (ctrl_conn == NULL)
643 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
644 if (ctrl_msg == NULL)
647 i = udev_ctrl_get_set_log_level(ctrl_msg);
649 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
650 udev_set_log_priority(udev, i);
651 worker_kill(udev, 0);
654 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
655 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
656 stop_exec_queue = true;
659 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
660 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
661 stop_exec_queue = false;
664 if (udev_ctrl_get_reload(ctrl_msg) > 0) {
665 info(udev, "udevd message (RELOAD) received\n");
669 str = udev_ctrl_get_set_env(ctrl_msg);
677 val = strchr(key, '=');
681 if (val[0] == '\0') {
682 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
683 udev_add_property(udev, key, NULL);
685 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
686 udev_add_property(udev, key, val);
689 err(udev, "wrong key format '%s'\n", key);
693 worker_kill(udev, 0);
696 i = udev_ctrl_get_set_children_max(ctrl_msg);
698 info(udev, "udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
702 if (udev_ctrl_get_ping(ctrl_msg) > 0)
703 info(udev, "udevd message (SYNC) received\n");
705 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
706 info(udev, "udevd message (EXIT) received\n");
708 /* keep reference to block the client until we exit */
709 udev_ctrl_connection_ref(ctrl_conn);
712 udev_ctrl_msg_unref(ctrl_msg);
713 return udev_ctrl_connection_unref(ctrl_conn);
716 /* read inotify messages */
717 static int handle_inotify(struct udev *udev)
721 struct inotify_event *ev;
723 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
726 buf = malloc(nbytes);
728 err(udev, "error getting buffer for inotify\n");
732 nbytes = read(fd_inotify, buf, nbytes);
734 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
735 struct udev_device *dev;
737 ev = (struct inotify_event *)(buf + pos);
738 dev = udev_watch_lookup(udev, ev->wd);
740 info(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
741 if (ev->mask & IN_CLOSE_WRITE) {
742 char filename[UTIL_PATH_SIZE];
745 info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
746 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
747 fd = open(filename, O_WRONLY);
749 if (write(fd, "change", 6) < 0)
750 info(udev, "error writing uevent: %m\n");
754 if (ev->mask & IN_IGNORED)
755 udev_watch_end(udev, dev);
757 udev_device_unref(dev);
766 static void handle_signal(struct udev *udev, int signo)
777 struct udev_list_node *loop, *tmp;
779 pid = waitpid(-1, &status, WNOHANG);
783 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
784 struct worker *worker = node_to_worker(loop);
786 if (worker->pid != pid)
788 info(udev, "worker [%u] exit\n", pid);
790 if (WIFEXITED(status)) {
791 if (WEXITSTATUS(status) != 0)
792 err(udev, "worker [%u] exit with return code %i\n", pid, WEXITSTATUS(status));
793 } else if (WIFSIGNALED(status)) {
794 err(udev, "worker [%u] terminated by signal %i (%s)\n",
795 pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
796 } else if (WIFSTOPPED(status)) {
797 err(udev, "worker [%u] stopped\n", pid);
798 } else if (WIFCONTINUED(status)) {
799 err(udev, "worker [%u] continued\n", pid);
801 err(udev, "worker [%u] exit with status 0x%04x\n", pid, status);
804 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
806 err(udev, "worker [%u] failed while handling '%s'\n",
807 pid, worker->event->devpath);
808 worker->event->exitcode = -32;
809 event_queue_delete(worker->event, true);
810 /* drop reference taken for state 'running' */
811 worker_unref(worker);
814 worker_unref(worker);
825 static void static_dev_create_from_modules(struct udev *udev)
827 struct utsname kernel;
828 char modules[UTIL_PATH_SIZE];
833 util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
834 f = fopen(modules, "r");
838 while (fgets(buf, sizeof(buf), f) != NULL) {
846 char filename[UTIL_PATH_SIZE];
852 s = strchr(modname, ' ');
858 s = strchr(devname, ' ');
864 s = strchr(devno, ' ');
866 s = strchr(devno, '\n');
869 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
874 else if (type == 'b')
879 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
880 util_create_path_selinux(udev, filename);
881 udev_selinux_setfscreatecon(udev, filename, mode);
882 info(udev, "mknod '%s' %c%u:%u\n", filename, type, maj, min);
883 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
884 utimensat(AT_FDCWD, filename, NULL, 0);
885 udev_selinux_resetfscreatecon(udev);
891 static int copy_dev_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
895 for (dent = readdir(dir_from); dent != NULL; dent = readdir(dir_from)) {
898 if (dent->d_name[0] == '.')
900 if (fstatat(dirfd(dir_from), dent->d_name, &stats, AT_SYMLINK_NOFOLLOW) != 0)
903 if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
904 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, stats.st_mode & 0777);
905 if (mknodat(dirfd(dir_to), dent->d_name, stats.st_mode, stats.st_rdev) == 0) {
906 fchmodat(dirfd(dir_to), dent->d_name, stats.st_mode & 0777, 0);
907 fchownat(dirfd(dir_to), dent->d_name, stats.st_uid, stats.st_gid, 0);
909 utimensat(dirfd(dir_to), dent->d_name, NULL, 0);
911 udev_selinux_resetfscreatecon(udev);
912 } else if (S_ISLNK(stats.st_mode)) {
913 char target[UTIL_PATH_SIZE];
916 len = readlinkat(dirfd(dir_from), dent->d_name, target, sizeof(target));
917 if (len <= 0 || len == (ssize_t)sizeof(target))
920 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFLNK);
921 if (symlinkat(target, dirfd(dir_to), dent->d_name) < 0 && errno == EEXIST)
922 utimensat(dirfd(dir_to), dent->d_name, NULL, AT_SYMLINK_NOFOLLOW);
923 udev_selinux_resetfscreatecon(udev);
924 } else if (S_ISDIR(stats.st_mode)) {
925 DIR *dir2_from, *dir2_to;
930 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFDIR|0755);
931 mkdirat(dirfd(dir_to), dent->d_name, 0755);
932 udev_selinux_resetfscreatecon(udev);
934 dir2_to = fdopendir(openat(dirfd(dir_to), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
938 dir2_from = fdopendir(openat(dirfd(dir_from), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
939 if (dir2_from == NULL) {
944 copy_dev_dir(udev, dir2_from, dir2_to, maxdepth-1);
954 static void static_dev_create_links(struct udev *udev, DIR *dir)
960 static const struct stdlinks stdlinks[] = {
961 { "core", "/proc/kcore" },
962 { "fd", "/proc/self/fd" },
963 { "stdin", "/proc/self/fd/0" },
964 { "stdout", "/proc/self/fd/1" },
965 { "stderr", "/proc/self/fd/2" },
969 for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
972 if (stat(stdlinks[i].target, &sb) == 0) {
973 udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
974 if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
975 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
976 udev_selinux_resetfscreatecon(udev);
981 static void static_dev_create_from_devices(struct udev *udev, DIR *dir)
985 dir_from = opendir(UDEVLIBEXECDIR "/devices");
986 if (dir_from == NULL)
988 copy_dev_dir(udev, dir_from, dir, 8);
992 static void static_dev_create(struct udev *udev)
996 dir = opendir(udev_get_dev_path(udev));
1000 static_dev_create_links(udev, dir);
1001 static_dev_create_from_devices(udev, dir);
1006 static int mem_size_mb(void)
1010 long int memsize = -1;
1012 f = fopen("/proc/meminfo", "r");
1016 while (fgets(buf, sizeof(buf), f) != NULL) {
1019 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
1020 memsize = value / 1024;
1029 static int convert_db(struct udev *udev)
1031 char filename[UTIL_PATH_SIZE];
1033 struct udev_enumerate *udev_enumerate;
1034 struct udev_list_entry *list_entry;
1036 /* current database */
1037 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/data", NULL);
1038 if (access(filename, F_OK) >= 0)
1041 /* make sure we do not get here again */
1042 util_create_path(udev, filename);
1043 mkdir(filename, 0755);
1046 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/db", NULL);
1047 if (access(filename, F_OK) < 0)
1050 f = fopen("/dev/kmsg", "w");
1052 fprintf(f, "<30>udevd[%u]: converting old udev database\n", getpid());
1056 udev_enumerate = udev_enumerate_new(udev);
1057 if (udev_enumerate == NULL)
1059 udev_enumerate_scan_devices(udev_enumerate);
1060 udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
1061 struct udev_device *device;
1063 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
1067 /* try to find the old database for devices without a current one */
1068 if (udev_device_read_db(device, NULL) < 0) {
1072 char devpath[UTIL_PATH_SIZE];
1073 char from[UTIL_PATH_SIZE];
1077 /* find database in old location */
1078 id = udev_device_get_id_filename(device);
1079 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
1080 if (lstat(from, &stats) == 0) {
1082 udev_device_read_db(device, from);
1088 /* find old database with $subsys:$sysname name */
1089 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
1090 "/.udev/db/", udev_device_get_subsystem(device), ":",
1091 udev_device_get_sysname(device), NULL);
1092 if (lstat(from, &stats) == 0) {
1094 udev_device_read_db(device, from);
1100 /* find old database with the encoded devpath name */
1101 util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
1102 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", devpath, NULL);
1103 if (lstat(from, &stats) == 0) {
1105 udev_device_read_db(device, from);
1111 /* write out new database */
1113 udev_device_update_db(device);
1115 udev_device_unref(device);
1117 udev_enumerate_unref(udev_enumerate);
1121 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
1123 int ctrl = -1, netlink = -1;
1126 n = sd_listen_fds(true);
1130 for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
1131 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
1138 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
1148 if (ctrl < 0 || netlink < 0)
1151 info(udev, "ctrl=%i netlink=%i\n", ctrl, netlink);
1153 *rnetlink = netlink;
1157 static bool check_rules_timestamp(struct udev *udev)
1160 unsigned long long *stamp_usec;
1162 bool changed = false;
1164 n = udev_get_rules_path(udev, &p, &stamp_usec);
1165 for (i = 0; i < n; i++) {
1168 if (stat(p[i], &stats) < 0)
1171 if (stamp_usec[i] == ts_usec(&stats.st_mtim))
1175 if (stamp_usec[i] != 0) {
1176 info(udev, "reload - timestamp of '%s' changed\n", p[i]);
1180 /* update timestamp */
1181 stamp_usec[i] = ts_usec(&stats.st_mtim);
1187 int main(int argc, char *argv[])
1192 int daemonize = false;
1193 int resolve_names = 1;
1194 static const struct option options[] = {
1195 { "daemon", no_argument, NULL, 'd' },
1196 { "debug", no_argument, NULL, 'D' },
1197 { "children-max", required_argument, NULL, 'c' },
1198 { "exec-delay", required_argument, NULL, 'e' },
1199 { "resolve-names", required_argument, NULL, 'N' },
1200 { "help", no_argument, NULL, 'h' },
1201 { "version", no_argument, NULL, 'V' },
1205 int fd_netlink = -1;
1207 struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
1208 struct udev_ctrl_connection *ctrl_conn = NULL;
1216 udev_log_init("udevd");
1217 udev_set_log_fn(udev, udev_main_log);
1218 info(udev, "version %s\n", VERSION);
1219 udev_selinux_init(udev);
1224 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1233 children_max = strtoul(optarg, NULL, 0);
1236 exec_delay = strtoul(optarg, NULL, 0);
1240 if (udev_get_log_priority(udev) < LOG_INFO)
1241 udev_set_log_priority(udev, LOG_INFO);
1244 if (strcmp (optarg, "early") == 0) {
1246 } else if (strcmp (optarg, "late") == 0) {
1248 } else if (strcmp (optarg, "never") == 0) {
1251 fprintf(stderr, "resolve-names must be early, late or never\n");
1252 err(udev, "resolve-names must be early, late or never\n");
1257 printf("Usage: udevd OPTIONS\n"
1260 " --children-max=<maximum number of workers>\n"
1261 " --exec-delay=<seconds to wait before executing RUN=>\n"
1262 " --resolve-names=early|late|never\n"
1268 printf("%s\n", VERSION);
1276 * read the kernel commandline, in case we need to get into debug mode
1277 * udev.log-priority=<level> syslog priority
1278 * udev.children-max=<number of workers> events are fully serialized if set to 1
1281 f = fopen("/proc/cmdline", "r");
1285 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1288 pos = strstr(cmdline, "udev.log-priority=");
1290 pos += strlen("udev.log-priority=");
1291 udev_set_log_priority(udev, util_log_priority(pos));
1294 pos = strstr(cmdline, "udev.children-max=");
1296 pos += strlen("udev.children-max=");
1297 children_max = strtoul(pos, NULL, 0);
1300 pos = strstr(cmdline, "udev.exec-delay=");
1302 pos += strlen("udev.exec-delay=");
1303 exec_delay = strtoul(pos, NULL, 0);
1309 if (getuid() != 0) {
1310 fprintf(stderr, "root privileges required\n");
1311 err(udev, "root privileges required\n");
1315 /* set umask before creating any file/directory */
1320 mkdir(udev_get_run_path(udev), 0755);
1322 /* create standard links, copy static nodes, create nodes from modules */
1323 static_dev_create(udev);
1324 static_dev_create_from_modules(udev);
1326 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1330 fd = open("/dev/null", O_RDWR);
1332 if (write(STDOUT_FILENO, 0, 0) < 0)
1333 dup2(fd, STDOUT_FILENO);
1334 if (write(STDERR_FILENO, 0, 0) < 0)
1335 dup2(fd, STDERR_FILENO);
1336 if (fd > STDERR_FILENO)
1339 fprintf(stderr, "cannot open /dev/null\n");
1340 err(udev, "cannot open /dev/null\n");
1344 if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1345 /* get control and netlink socket from from systemd */
1346 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1347 if (udev_ctrl == NULL) {
1348 err(udev, "error taking over udev control socket");
1353 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1354 if (monitor == NULL) {
1355 err(udev, "error taking over netlink socket\n");
1360 /* open control and netlink socket */
1361 udev_ctrl = udev_ctrl_new(udev);
1362 if (udev_ctrl == NULL) {
1363 fprintf(stderr, "error initializing udev control socket");
1364 err(udev, "error initializing udev control socket");
1368 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1370 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1371 if (monitor == NULL) {
1372 fprintf(stderr, "error initializing netlink socket\n");
1373 err(udev, "error initializing netlink socket\n");
1377 fd_netlink = udev_monitor_get_fd(monitor);
1380 if (udev_monitor_enable_receiving(monitor) < 0) {
1381 fprintf(stderr, "error binding netlink socket\n");
1382 err(udev, "error binding netlink socket\n");
1387 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1388 fprintf(stderr, "error binding udev control socket\n");
1389 err(udev, "error binding udev control socket\n");
1394 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1396 /* create queue file before signalling 'ready', to make sure we block 'settle' */
1397 udev_queue_export = udev_queue_export_new(udev);
1398 if (udev_queue_export == NULL) {
1399 err(udev, "error creating queue file\n");
1412 err(udev, "fork of daemon failed: %m\n");
1417 goto exit_daemonize;
1422 fd = open("/proc/self/oom_score_adj", O_RDWR);
1424 /* Fallback to old interface */
1425 fd = open("/proc/self/oom_adj", O_RDWR);
1427 err(udev, "error disabling OOM: %m\n");
1429 /* OOM_DISABLE == -17 */
1430 write(fd, "-17", 3);
1434 write(fd, "-1000", 5);
1438 sd_notify(1, "READY=1");
1441 f = fopen("/dev/kmsg", "w");
1443 fprintf(f, "<30>udevd[%u]: starting version " VERSION "\n", getpid());
1450 fd = open("/dev/null", O_RDWR);
1452 dup2(fd, STDIN_FILENO);
1453 dup2(fd, STDOUT_FILENO);
1454 dup2(fd, STDERR_FILENO);
1459 fd_inotify = udev_watch_init(udev);
1460 if (fd_inotify < 0) {
1461 fprintf(stderr, "error initializing inotify\n");
1462 err(udev, "error initializing inotify\n");
1466 udev_watch_restore(udev);
1468 /* block and listen to all signals on signalfd */
1470 sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1471 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1472 if (fd_signal < 0) {
1473 fprintf(stderr, "error creating signalfd\n");
1474 err(udev, "error creating signalfd\n");
1479 /* unnamed socket from workers to the main daemon */
1480 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1481 fprintf(stderr, "error creating socketpair\n");
1482 err(udev, "error creating socketpair\n");
1486 fd_worker = worker_watch[READ_END];
1488 udev_builtin_init(udev);
1490 rules = udev_rules_new(udev, resolve_names);
1491 if (rules == NULL) {
1492 err(udev, "error reading rules\n");
1496 memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1497 ep_ctrl.events = EPOLLIN;
1498 ep_ctrl.data.fd = fd_ctrl;
1500 memset(&ep_inotify, 0, sizeof(struct epoll_event));
1501 ep_inotify.events = EPOLLIN;
1502 ep_inotify.data.fd = fd_inotify;
1504 memset(&ep_signal, 0, sizeof(struct epoll_event));
1505 ep_signal.events = EPOLLIN;
1506 ep_signal.data.fd = fd_signal;
1508 memset(&ep_netlink, 0, sizeof(struct epoll_event));
1509 ep_netlink.events = EPOLLIN;
1510 ep_netlink.data.fd = fd_netlink;
1512 memset(&ep_worker, 0, sizeof(struct epoll_event));
1513 ep_worker.events = EPOLLIN;
1514 ep_worker.data.fd = fd_worker;
1516 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1518 err(udev, "error creating epoll fd: %m\n");
1521 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1522 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1523 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1524 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1525 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1526 err(udev, "fail to add fds to epoll: %m\n");
1530 /* if needed, convert old database from earlier udev version */
1533 if (children_max <= 0) {
1534 int memsize = mem_size_mb();
1536 /* set value depending on the amount of RAM */
1538 children_max = 128 + (memsize / 8);
1542 info(udev, "set children_max to %u\n", children_max);
1544 udev_rules_apply_static_dev_perms(rules);
1546 udev_list_node_init(&event_list);
1547 udev_list_node_init(&worker_list);
1550 static unsigned long long last_usec;
1551 struct epoll_event ev[8];
1554 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1558 /* close sources of new events and discard buffered events */
1560 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1563 if (monitor != NULL) {
1564 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1565 udev_monitor_unref(monitor);
1568 if (fd_inotify >= 0) {
1569 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1574 /* discard queued events and kill workers */
1575 event_queue_cleanup(udev, EVENT_QUEUED);
1576 worker_kill(udev, 0);
1578 /* exit after all has cleaned up */
1579 if (udev_list_node_is_empty(&event_list) && udev_list_node_is_empty(&worker_list))
1582 /* timeout at exit for workers to finish */
1583 timeout = 30 * 1000;
1584 } else if (udev_list_node_is_empty(&event_list) && children <= 2) {
1588 /* kill idle or hanging workers */
1591 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
1596 struct udev_list_node *loop;
1600 err(udev, "timeout, giving up waiting for workers to finish\n");
1604 /* kill idle workers */
1605 if (udev_list_node_is_empty(&event_list)) {
1606 info(udev, "cleanup idle workers\n");
1607 worker_kill(udev, 2);
1610 /* check for hanging events */
1611 udev_list_node_foreach(loop, &worker_list) {
1612 struct worker *worker = node_to_worker(loop);
1614 if (worker->state != WORKER_RUNNING)
1617 if ((now_usec() - worker->event_start_usec) > 30 * 1000 * 1000) {
1618 err(udev, "worker [%u] timeout, kill it\n", worker->pid,
1619 worker->event ? worker->event->devpath : "<idle>");
1620 kill(worker->pid, SIGKILL);
1621 worker->state = WORKER_KILLED;
1622 /* drop reference taken for state 'running' */
1623 worker_unref(worker);
1624 if (worker->event) {
1625 err(udev, "seq %llu '%s' killed\n",
1626 udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1627 worker->event->exitcode = -64;
1628 event_queue_delete(worker->event, true);
1629 worker->event = NULL;
1636 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1637 for (i = 0; i < fdcount; i++) {
1638 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1640 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1642 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1644 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1646 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1650 /* check for changed config, every 3 seconds at most */
1651 if ((now_usec() - last_usec) > 3 * 1000 * 1000) {
1652 if (check_rules_timestamp(udev))
1654 if (udev_builtin_validate(udev))
1657 last_usec = now_usec();
1660 /* reload requested, HUP signal received, rules changed, builtin changed */
1662 worker_kill(udev, 0);
1663 rules = udev_rules_unref(rules);
1664 udev_builtin_exit(udev);
1668 /* event has finished */
1670 worker_returned(fd_worker);
1673 struct udev_device *dev;
1675 dev = udev_monitor_receive_device(monitor);
1677 udev_device_set_usec_initialized(dev, now_usec());
1678 if (event_queue_insert(dev) < 0)
1679 udev_device_unref(dev);
1683 /* start new events */
1684 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1686 rules = udev_rules_new(udev, resolve_names);
1688 event_queue_start(udev);
1692 struct signalfd_siginfo fdsi;
1695 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1696 if (size == sizeof(struct signalfd_siginfo))
1697 handle_signal(udev, fdsi.ssi_signo);
1700 /* we are shutting down, the events below are not handled anymore */
1704 /* device node watch */
1706 handle_inotify(udev);
1709 * This needs to be after the inotify handling, to make sure,
1710 * that the ping is send back after the possibly generated
1711 * "change" events by the inotify device node watch.
1713 * A single time we may receive a client connection which we need to
1714 * keep open to block the client. It will be closed right before we
1718 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1723 udev_queue_export_cleanup(udev_queue_export);
1724 udev_ctrl_cleanup(udev_ctrl);
1728 worker_list_cleanup(udev);
1729 event_queue_cleanup(udev, EVENT_UNDEF);
1730 udev_rules_unref(rules);
1731 udev_builtin_exit(udev);
1734 if (worker_watch[READ_END] >= 0)
1735 close(worker_watch[READ_END]);
1736 if (worker_watch[WRITE_END] >= 0)
1737 close(worker_watch[WRITE_END]);
1738 udev_monitor_unref(monitor);
1739 udev_queue_export_unref(udev_queue_export);
1740 udev_ctrl_connection_unref(ctrl_conn);
1741 udev_ctrl_unref(udev_ctrl);
1742 udev_selinux_exit(udev);