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 orig_sigmask;
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]);
251 udev_log_init("udevd-work");
254 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
256 err(udev, "error creating signalfd %m\n");
261 fd_ep = epoll_create1(EPOLL_CLOEXEC);
263 err(udev, "error creating epoll fd: %m\n");
268 memset(&ep_signal, 0, sizeof(struct epoll_event));
269 ep_signal.events = EPOLLIN;
270 ep_signal.data.fd = fd_signal;
272 fd_monitor = udev_monitor_get_fd(worker_monitor);
273 memset(&ep_monitor, 0, sizeof(struct epoll_event));
274 ep_monitor.events = EPOLLIN;
275 ep_monitor.data.fd = fd_monitor;
277 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
278 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
279 err(udev, "fail to add fds to epoll: %m\n");
284 /* request TERM signal if parent exits */
285 prctl(PR_SET_PDEATHSIG, SIGTERM);
288 struct udev_event *udev_event;
289 struct worker_message msg = {};
293 info(udev, "seq %llu running\n", udev_device_get_seqnum(dev));
294 udev_event = udev_event_new(dev);
295 if (udev_event == NULL) {
300 /* set timeout to prevent hanging processes */
301 alarm(UDEV_EVENT_TIMEOUT);
304 udev_event->exec_delay = exec_delay;
306 /* apply rules, create node, symlinks */
307 err = udev_event_execute_rules(udev_event, rules);
309 /* rules may change/disable the timeout */
310 if (udev_device_get_event_timeout(dev) >= 0)
311 alarm(udev_device_get_event_timeout(dev));
314 failed = udev_event_execute_run(udev_event, &orig_sigmask);
318 /* apply/restore inotify watch */
319 if (err == 0 && udev_event->inotify_watch) {
320 udev_watch_begin(udev, dev);
321 udev_device_update_db(dev);
324 /* send processed event back to libudev listeners */
325 udev_monitor_send_device(worker_monitor, NULL, dev);
327 /* send udevd the result of the event execution */
330 else if (failed != 0)
331 msg.exitcode = failed;
333 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
335 info(udev, "seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
336 udev_event_unref(udev_event);
337 udev_device_unref(dev);
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);
350 for (i = 0; i < fdcount; i++) {
351 if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
352 dev = udev_monitor_receive_device(worker_monitor);
353 } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
354 struct signalfd_siginfo fdsi;
357 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
358 if (size != sizeof(struct signalfd_siginfo))
360 switch (fdsi.ssi_signo) {
372 udev_device_unref(dev);
378 close(worker_watch[WRITE_END]);
379 udev_rules_unref(rules);
380 udev_monitor_unref(worker_monitor);
386 udev_monitor_unref(worker_monitor);
387 event->state = EVENT_QUEUED;
389 err(udev, "fork of child failed: %m\n");
392 /* close monitor, but keep address around */
393 udev_monitor_disconnect(worker_monitor);
394 worker->monitor = worker_monitor;
396 worker->state = WORKER_RUNNING;
397 worker->event = event;
398 event->state = EVENT_RUNNING;
399 udev_list_node_append(&worker->node, &worker_list);
401 info(udev, "seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
406 static void event_run(struct event *event, bool force)
408 struct udev_list_node *loop;
410 udev_list_node_foreach(loop, &worker_list) {
411 struct worker *worker = node_to_worker(loop);
414 if (worker->state != WORKER_IDLE)
417 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
419 err(event->udev, "worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
420 kill(worker->pid, SIGKILL);
421 worker->state = WORKER_KILLED;
425 worker->event = event;
426 worker->state = WORKER_RUNNING;
427 event->state = EVENT_RUNNING;
431 if (!force && children >= children_max) {
432 if (children_max > 1)
433 info(event->udev, "maximum number (%i) of children reached\n", children);
437 /* start new worker and pass initial device */
441 static int event_queue_insert(struct udev_device *dev)
445 event = calloc(1, sizeof(struct event));
449 event->udev = udev_device_get_udev(dev);
451 event->seqnum = udev_device_get_seqnum(dev);
452 event->devpath = udev_device_get_devpath(dev);
453 event->devpath_len = strlen(event->devpath);
454 event->devpath_old = udev_device_get_devpath_old(dev);
455 event->devnum = udev_device_get_devnum(dev);
456 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
457 event->ifindex = udev_device_get_ifindex(dev);
459 udev_queue_export_device_queued(udev_queue_export, dev);
460 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
461 udev_device_get_action(dev), udev_device_get_subsystem(dev));
463 event->state = EVENT_QUEUED;
464 udev_list_node_append(&event->node, &event_list);
466 /* run all events with a timeout set immediately */
467 if (udev_device_get_timeout(dev) > 0) {
468 event_run(event, true);
475 static void worker_kill(struct udev *udev, int retain)
477 struct udev_list_node *loop;
480 if (children <= retain)
483 max = children - retain;
485 udev_list_node_foreach(loop, &worker_list) {
486 struct worker *worker = node_to_worker(loop);
491 if (worker->state == WORKER_KILLED)
494 worker->state = WORKER_KILLED;
495 kill(worker->pid, SIGTERM);
499 /* lookup event for identical, parent, child device */
500 static bool is_devpath_busy(struct event *event)
502 struct udev_list_node *loop;
505 /* check if queue contains events we depend on */
506 udev_list_node_foreach(loop, &event_list) {
507 struct event *loop_event = node_to_event(loop);
509 /* we already found a later event, earlier can not block us, no need to check again */
510 if (loop_event->seqnum < event->delaying_seqnum)
513 /* event we checked earlier still exists, no need to check again */
514 if (loop_event->seqnum == event->delaying_seqnum)
517 /* found ourself, no later event can block us */
518 if (loop_event->seqnum >= event->seqnum)
521 /* check major/minor */
522 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
525 /* check network device ifindex */
526 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
529 /* check our old name */
530 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
531 event->delaying_seqnum = loop_event->seqnum;
535 /* compare devpath */
536 common = MIN(loop_event->devpath_len, event->devpath_len);
538 /* one devpath is contained in the other? */
539 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
542 /* identical device event found */
543 if (loop_event->devpath_len == event->devpath_len) {
544 /* devices names might have changed/swapped in the meantime */
545 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
547 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
549 event->delaying_seqnum = loop_event->seqnum;
553 /* parent device event found */
554 if (event->devpath[common] == '/') {
555 event->delaying_seqnum = loop_event->seqnum;
559 /* child device event found */
560 if (loop_event->devpath[common] == '/') {
561 event->delaying_seqnum = loop_event->seqnum;
565 /* no matching device */
572 static void event_queue_start(struct udev *udev)
574 struct udev_list_node *loop;
576 udev_list_node_foreach(loop, &event_list) {
577 struct event *event = node_to_event(loop);
579 if (event->state != EVENT_QUEUED)
582 /* do not start event if parent or child event is still running */
583 if (is_devpath_busy(event)) {
584 dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath);
588 event_run(event, false);
592 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
594 struct udev_list_node *loop, *tmp;
596 udev_list_node_foreach_safe(loop, tmp, &event_list) {
597 struct event *event = node_to_event(loop);
599 if (match_type != EVENT_UNDEF && match_type != event->state)
602 event_queue_delete(event, false);
606 static void worker_returned(int fd_worker)
609 struct worker_message msg;
611 struct udev_list_node *loop;
613 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
614 if (size != sizeof(struct worker_message))
617 /* lookup worker who sent the signal */
618 udev_list_node_foreach(loop, &worker_list) {
619 struct worker *worker = node_to_worker(loop);
621 if (worker->pid != msg.pid)
624 /* worker returned */
625 worker->event->exitcode = msg.exitcode;
626 event_queue_delete(worker->event, true);
627 worker->event = NULL;
628 if (worker->state != WORKER_KILLED)
629 worker->state = WORKER_IDLE;
630 worker_unref(worker);
636 /* receive the udevd message from userspace */
637 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
639 struct udev *udev = udev_ctrl_get_udev(uctrl);
640 struct udev_ctrl_connection *ctrl_conn;
641 struct udev_ctrl_msg *ctrl_msg = NULL;
645 ctrl_conn = udev_ctrl_get_connection(uctrl);
646 if (ctrl_conn == NULL)
649 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
650 if (ctrl_msg == NULL)
653 i = udev_ctrl_get_set_log_level(ctrl_msg);
655 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
656 udev_set_log_priority(udev, i);
657 worker_kill(udev, 0);
660 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
661 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
662 stop_exec_queue = true;
665 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
666 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
667 stop_exec_queue = false;
670 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
671 info(udev, "udevd message (RELOAD_RULES) received\n");
672 reload_config = true;
675 str = udev_ctrl_get_set_env(ctrl_msg);
683 val = strchr(key, '=');
687 if (val[0] == '\0') {
688 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
689 udev_add_property(udev, key, NULL);
691 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
692 udev_add_property(udev, key, val);
695 err(udev, "wrong key format '%s'\n", key);
699 worker_kill(udev, 0);
702 i = udev_ctrl_get_set_children_max(ctrl_msg);
704 info(udev, "udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
708 if (udev_ctrl_get_ping(ctrl_msg) > 0)
709 info(udev, "udevd message (SYNC) received\n");
711 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
712 info(udev, "udevd message (EXIT) received\n");
714 /* keep reference to block the client until we exit */
715 udev_ctrl_connection_ref(ctrl_conn);
718 udev_ctrl_msg_unref(ctrl_msg);
719 return udev_ctrl_connection_unref(ctrl_conn);
722 /* read inotify messages */
723 static int handle_inotify(struct udev *udev)
727 struct inotify_event *ev;
729 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
732 buf = malloc(nbytes);
734 err(udev, "error getting buffer for inotify\n");
738 nbytes = read(fd_inotify, buf, nbytes);
740 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
741 struct udev_device *dev;
743 ev = (struct inotify_event *)(buf + pos);
747 info(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
748 s = strstr(ev->name, ".rules");
751 if (strlen(s) != strlen(".rules"))
753 reload_config = true;
757 dev = udev_watch_lookup(udev, ev->wd);
759 info(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
760 if (ev->mask & IN_CLOSE_WRITE) {
761 char filename[UTIL_PATH_SIZE];
764 info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
765 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
766 fd = open(filename, O_WRONLY);
768 if (write(fd, "change", 6) < 0)
769 info(udev, "error writing uevent: %m\n");
773 if (ev->mask & IN_IGNORED)
774 udev_watch_end(udev, dev);
776 udev_device_unref(dev);
785 static void handle_signal(struct udev *udev, int signo)
796 struct udev_list_node *loop, *tmp;
798 pid = waitpid(-1, &status, WNOHANG);
802 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
803 struct worker *worker = node_to_worker(loop);
805 if (worker->pid != pid)
808 info(udev, "worker [%u] exit\n", pid);
809 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
810 err(udev, "worker [%u] unexpectedly returned with status 0x%04x\n", pid, status);
811 if (worker->event != NULL) {
812 err(udev, "worker [%u] failed while handling '%s'\n", pid, worker->event->devpath);
813 worker->event->exitcode = -32;
814 event_queue_delete(worker->event, true);
815 /* drop reference from running event */
816 worker_unref(worker);
819 worker_unref(worker);
825 reload_config = true;
830 static void static_dev_create_from_modules(struct udev *udev)
832 struct utsname kernel;
833 char modules[UTIL_PATH_SIZE];
838 util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
839 f = fopen(modules, "r");
843 while (fgets(buf, sizeof(buf), f) != NULL) {
851 char filename[UTIL_PATH_SIZE];
857 s = strchr(modname, ' ');
863 s = strchr(devname, ' ');
869 s = strchr(devno, ' ');
871 s = strchr(devno, '\n');
874 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
878 mode = 0600 | S_IFCHR;
879 else if (type == 'b')
880 mode = 0600 | S_IFBLK;
884 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
885 util_create_path_selinux(udev, filename);
886 udev_selinux_setfscreatecon(udev, filename, mode);
887 info(udev, "mknod '%s' %c%u:%u\n", filename, type, maj, min);
888 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
889 utimensat(AT_FDCWD, filename, NULL, 0);
890 udev_selinux_resetfscreatecon(udev);
896 static int copy_dev_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
900 for (dent = readdir(dir_from); dent != NULL; dent = readdir(dir_from)) {
903 if (dent->d_name[0] == '.')
905 if (fstatat(dirfd(dir_from), dent->d_name, &stats, AT_SYMLINK_NOFOLLOW) != 0)
908 if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
909 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, stats.st_mode & 0777);
910 if (mknodat(dirfd(dir_to), dent->d_name, stats.st_mode, stats.st_rdev) == 0) {
911 fchmodat(dirfd(dir_to), dent->d_name, stats.st_mode & 0777, 0);
912 fchownat(dirfd(dir_to), dent->d_name, stats.st_uid, stats.st_gid, 0);
914 utimensat(dirfd(dir_to), dent->d_name, NULL, 0);
916 udev_selinux_resetfscreatecon(udev);
917 } else if (S_ISLNK(stats.st_mode)) {
918 char target[UTIL_PATH_SIZE];
921 len = readlinkat(dirfd(dir_from), dent->d_name, target, sizeof(target));
922 if (len <= 0 || len == (ssize_t)sizeof(target))
925 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFLNK);
926 if (symlinkat(target, dirfd(dir_to), dent->d_name) < 0 && errno == EEXIST)
927 utimensat(dirfd(dir_to), dent->d_name, NULL, AT_SYMLINK_NOFOLLOW);
928 udev_selinux_resetfscreatecon(udev);
929 } else if (S_ISDIR(stats.st_mode)) {
930 DIR *dir2_from, *dir2_to;
935 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFDIR|0755);
936 mkdirat(dirfd(dir_to), dent->d_name, 0755);
937 udev_selinux_resetfscreatecon(udev);
939 dir2_to = fdopendir(openat(dirfd(dir_to), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
943 dir2_from = fdopendir(openat(dirfd(dir_from), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
944 if (dir2_from == NULL) {
949 copy_dev_dir(udev, dir2_from, dir2_to, maxdepth-1);
959 static void static_dev_create_links(struct udev *udev, DIR *dir)
965 static const struct stdlinks stdlinks[] = {
966 { "core", "/proc/kcore" },
967 { "fd", "/proc/self/fd" },
968 { "stdin", "/proc/self/fd/0" },
969 { "stdout", "/proc/self/fd/1" },
970 { "stderr", "/proc/self/fd/2" },
974 for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
977 if (stat(stdlinks[i].target, &sb) == 0) {
978 udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
979 if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
980 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
981 udev_selinux_resetfscreatecon(udev);
986 static void static_dev_create_from_devices(struct udev *udev, DIR *dir)
990 dir_from = opendir(LIBEXECDIR "/devices");
991 if (dir_from == NULL)
993 copy_dev_dir(udev, dir_from, dir, 8);
997 static void static_dev_create(struct udev *udev)
1001 dir = opendir(udev_get_dev_path(udev));
1005 static_dev_create_links(udev, dir);
1006 static_dev_create_from_devices(udev, dir);
1011 static int mem_size_mb(void)
1015 long int memsize = -1;
1017 f = fopen("/proc/meminfo", "r");
1021 while (fgets(buf, sizeof(buf), f) != NULL) {
1024 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
1025 memsize = value / 1024;
1034 static int convert_db(struct udev *udev)
1036 char filename[UTIL_PATH_SIZE];
1038 struct udev_enumerate *udev_enumerate;
1039 struct udev_list_entry *list_entry;
1041 /* current database */
1042 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/data", NULL);
1043 if (access(filename, F_OK) >= 0)
1046 /* make sure we do not get here again */
1047 util_create_path(udev, filename);
1048 mkdir(filename, 0755);
1051 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/db", NULL);
1052 if (access(filename, F_OK) < 0)
1055 f = fopen("/dev/kmsg", "w");
1057 fprintf(f, "<30>udev[%u]: converting old udev database\n", getpid());
1061 udev_enumerate = udev_enumerate_new(udev);
1062 if (udev_enumerate == NULL)
1064 udev_enumerate_scan_devices(udev_enumerate);
1065 udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
1066 struct udev_device *device;
1068 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
1072 /* try to find the old database for devices without a current one */
1073 if (udev_device_read_db(device, NULL) < 0) {
1077 char devpath[UTIL_PATH_SIZE];
1078 char from[UTIL_PATH_SIZE];
1082 /* find database in old location */
1083 id = udev_device_get_id_filename(device);
1084 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
1085 if (lstat(from, &stats) == 0) {
1087 udev_device_read_db(device, from);
1093 /* find old database with $subsys:$sysname name */
1094 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
1095 "/.udev/db/", udev_device_get_subsystem(device), ":",
1096 udev_device_get_sysname(device), NULL);
1097 if (lstat(from, &stats) == 0) {
1099 udev_device_read_db(device, from);
1105 /* find old database with the encoded devpath name */
1106 util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
1107 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", devpath, NULL);
1108 if (lstat(from, &stats) == 0) {
1110 udev_device_read_db(device, from);
1116 /* write out new database */
1118 udev_device_update_db(device);
1120 udev_device_unref(device);
1122 udev_enumerate_unref(udev_enumerate);
1126 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
1128 int ctrl = -1, netlink = -1;
1131 n = sd_listen_fds(true);
1135 for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
1136 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
1143 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
1153 if (ctrl < 0 || netlink < 0)
1156 info(udev, "ctrl=%i netlink=%i\n", ctrl, netlink);
1158 *rnetlink = netlink;
1162 int main(int argc, char *argv[])
1167 int daemonize = false;
1168 int resolve_names = 1;
1169 static const struct option options[] = {
1170 { "daemon", no_argument, NULL, 'd' },
1171 { "debug", no_argument, NULL, 'D' },
1172 { "children-max", required_argument, NULL, 'c' },
1173 { "exec-delay", required_argument, NULL, 'e' },
1174 { "resolve-names", required_argument, NULL, 'N' },
1175 { "help", no_argument, NULL, 'h' },
1176 { "version", no_argument, NULL, 'V' },
1180 int fd_netlink = -1;
1182 struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
1183 struct udev_ctrl_connection *ctrl_conn = NULL;
1190 udev_log_init("udevd");
1191 udev_set_log_fn(udev, log_fn);
1192 info(udev, "version %s\n", VERSION);
1193 udev_selinux_init(udev);
1195 /* make sure, that our runtime dir exists and is writable */
1196 if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) < 0) {
1197 /* try to create our own subdirectory, do not create parent directories */
1198 mkdir(udev_get_run_config_path(udev), 0755);
1200 if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) >= 0) {
1201 /* directory seems writable now */
1202 udev_set_run_path(udev, udev_get_run_config_path(udev));
1204 /* fall back to /dev/.udev */
1205 char filename[UTIL_PATH_SIZE];
1207 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev", NULL);
1208 if (udev_set_run_path(udev, filename) == NULL)
1210 mkdir(udev_get_run_path(udev), 0755);
1211 err(udev, "error: runtime directory '%s' not writable, for now falling back to '%s'",
1212 udev_get_run_config_path(udev), udev_get_run_path(udev));
1215 /* relabel runtime dir only if it resides below /dev */
1216 if (strncmp(udev_get_run_path(udev), udev_get_dev_path(udev), strlen(udev_get_dev_path(udev))) == 0)
1217 udev_selinux_lsetfilecon(udev, udev_get_run_path(udev), 0755);
1218 info(udev, "runtime dir '%s'\n", udev_get_run_path(udev));
1223 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1232 children_max = strtoul(optarg, NULL, 0);
1235 exec_delay = strtoul(optarg, NULL, 0);
1239 if (udev_get_log_priority(udev) < LOG_INFO)
1240 udev_set_log_priority(udev, LOG_INFO);
1243 if (strcmp (optarg, "early") == 0) {
1245 } else if (strcmp (optarg, "late") == 0) {
1247 } else if (strcmp (optarg, "never") == 0) {
1250 fprintf(stderr, "resolve-names must be early, late or never\n");
1251 err(udev, "resolve-names must be early, late or never\n");
1256 printf("Usage: udevd OPTIONS\n"
1259 " --children-max=<maximum number of workers>\n"
1260 " --exec-delay=<seconds to wait before executing RUN=>\n"
1261 " --resolve-names=early|late|never\n"
1267 printf("%s\n", VERSION);
1275 * read the kernel commandline, in case we need to get into debug mode
1276 * udev.log-priority=<level> syslog priority
1277 * udev.children-max=<number of workers> events are fully serialized if set to 1
1280 f = fopen("/proc/cmdline", "r");
1284 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1287 pos = strstr(cmdline, "udev.log-priority=");
1289 pos += strlen("udev.log-priority=");
1290 udev_set_log_priority(udev, util_log_priority(pos));
1293 pos = strstr(cmdline, "udev.children-max=");
1295 pos += strlen("udev.children-max=");
1296 children_max = strtoul(pos, NULL, 0);
1299 pos = strstr(cmdline, "udev.exec-delay=");
1301 pos += strlen("udev.exec-delay=");
1302 exec_delay = strtoul(pos, NULL, 0);
1308 if (getuid() != 0) {
1309 fprintf(stderr, "root privileges required\n");
1310 err(udev, "root privileges required\n");
1314 /* set umask before creating any file/directory */
1318 /* create standard links, copy static nodes, create nodes from modules */
1319 static_dev_create(udev);
1320 static_dev_create_from_modules(udev);
1322 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1326 fd = open("/dev/null", O_RDWR);
1328 if (write(STDOUT_FILENO, 0, 0) < 0)
1329 dup2(fd, STDOUT_FILENO);
1330 if (write(STDERR_FILENO, 0, 0) < 0)
1331 dup2(fd, STDERR_FILENO);
1332 if (fd > STDERR_FILENO)
1335 fprintf(stderr, "cannot open /dev/null\n");
1336 err(udev, "cannot open /dev/null\n");
1340 if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1341 /* get control and netlink socket from from systemd */
1342 udev_ctrl = udev_ctrl_new_from_socket_fd(udev, UDEV_CTRL_SOCK_PATH, fd_ctrl);
1343 if (udev_ctrl == NULL) {
1344 err(udev, "error taking over udev control socket");
1349 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1350 if (monitor == NULL) {
1351 err(udev, "error taking over netlink socket\n");
1356 /* open control and netlink socket */
1357 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
1358 if (udev_ctrl == NULL) {
1359 fprintf(stderr, "error initializing udev control socket");
1360 err(udev, "error initializing udev control socket");
1364 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1366 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1367 if (monitor == NULL) {
1368 fprintf(stderr, "error initializing netlink socket\n");
1369 err(udev, "error initializing netlink socket\n");
1373 fd_netlink = udev_monitor_get_fd(monitor);
1376 if (udev_monitor_enable_receiving(monitor) < 0) {
1377 fprintf(stderr, "error binding netlink socket\n");
1378 err(udev, "error binding netlink socket\n");
1383 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1384 fprintf(stderr, "error binding udev control socket\n");
1385 err(udev, "error binding udev control socket\n");
1390 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1401 err(udev, "fork of daemon failed: %m\n");
1411 fd = open("/proc/self/oom_score_adj", O_RDWR);
1413 /* Fallback to old interface */
1414 fd = open("/proc/self/oom_adj", O_RDWR);
1416 err(udev, "error disabling OOM: %m\n");
1418 /* OOM_DISABLE == -17 */
1419 write(fd, "-17", 3);
1423 write(fd, "-1000", 5);
1427 sd_notify(1, "READY=1");
1430 f = fopen("/dev/kmsg", "w");
1432 fprintf(f, "<30>udev[%u]: starting version " VERSION "\n", getpid());
1439 fd = open("/dev/null", O_RDWR);
1441 dup2(fd, STDIN_FILENO);
1442 dup2(fd, STDOUT_FILENO);
1443 dup2(fd, STDERR_FILENO);
1448 fd_inotify = udev_watch_init(udev);
1449 if (fd_inotify < 0) {
1450 fprintf(stderr, "error initializing inotify\n");
1451 err(udev, "error initializing inotify\n");
1456 if (udev_get_rules_path(udev) != NULL) {
1457 inotify_add_watch(fd_inotify, udev_get_rules_path(udev),
1458 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1460 char filename[UTIL_PATH_SIZE];
1461 struct stat statbuf;
1463 inotify_add_watch(fd_inotify, LIBEXECDIR "/rules.d",
1464 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1465 inotify_add_watch(fd_inotify, SYSCONFDIR "/udev/rules.d",
1466 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1468 /* watch dynamic rules directory */
1469 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/rules.d", NULL);
1470 if (stat(filename, &statbuf) != 0) {
1471 util_create_path(udev, filename);
1472 mkdir(filename, 0755);
1474 inotify_add_watch(fd_inotify, filename,
1475 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1477 udev_watch_restore(udev);
1479 /* block and listen to all signals on signalfd */
1481 sigprocmask(SIG_SETMASK, &mask, &orig_sigmask);
1482 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1483 if (fd_signal < 0) {
1484 fprintf(stderr, "error creating signalfd\n");
1485 err(udev, "error creating signalfd\n");
1490 /* unnamed socket from workers to the main daemon */
1491 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1492 fprintf(stderr, "error creating socketpair\n");
1493 err(udev, "error creating socketpair\n");
1497 fd_worker = worker_watch[READ_END];
1499 rules = udev_rules_new(udev, resolve_names);
1500 if (rules == NULL) {
1501 err(udev, "error reading rules\n");
1505 udev_queue_export = udev_queue_export_new(udev);
1506 if (udev_queue_export == NULL) {
1507 err(udev, "error creating queue file\n");
1511 memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1512 ep_ctrl.events = EPOLLIN;
1513 ep_ctrl.data.fd = fd_ctrl;
1515 memset(&ep_inotify, 0, sizeof(struct epoll_event));
1516 ep_inotify.events = EPOLLIN;
1517 ep_inotify.data.fd = fd_inotify;
1519 memset(&ep_signal, 0, sizeof(struct epoll_event));
1520 ep_signal.events = EPOLLIN;
1521 ep_signal.data.fd = fd_signal;
1523 memset(&ep_netlink, 0, sizeof(struct epoll_event));
1524 ep_netlink.events = EPOLLIN;
1525 ep_netlink.data.fd = fd_netlink;
1527 memset(&ep_worker, 0, sizeof(struct epoll_event));
1528 ep_worker.events = EPOLLIN;
1529 ep_worker.data.fd = fd_worker;
1531 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1533 err(udev, "error creating epoll fd: %m\n");
1536 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1537 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1538 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1539 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1540 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1541 err(udev, "fail to add fds to epoll: %m\n");
1545 /* if needed, convert old database from earlier udev version */
1548 if (children_max <= 0) {
1549 int memsize = mem_size_mb();
1551 /* set value depending on the amount of RAM */
1553 children_max = 128 + (memsize / 8);
1557 info(udev, "set children_max to %u\n", children_max);
1559 udev_rules_apply_static_dev_perms(rules);
1561 udev_list_init(&event_list);
1562 udev_list_init(&worker_list);
1565 struct epoll_event ev[8];
1568 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1572 /* close sources of new events and discard buffered events */
1574 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1577 if (monitor != NULL) {
1578 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1579 udev_monitor_unref(monitor);
1582 if (fd_inotify >= 0) {
1583 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1588 /* discard queued events and kill workers */
1589 event_queue_cleanup(udev, EVENT_QUEUED);
1590 worker_kill(udev, 0);
1592 /* exit after all has cleaned up */
1593 if (udev_list_is_empty(&event_list) && udev_list_is_empty(&worker_list))
1596 /* timeout at exit for workers to finish */
1597 timeout = 60 * 1000;
1598 } else if (udev_list_is_empty(&event_list) && children > 2) {
1599 /* set timeout to kill idle workers */
1604 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
1610 info(udev, "timeout, giving up waiting for workers to finish\n");
1614 /* timeout - kill idle workers */
1615 worker_kill(udev, 2);
1618 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1619 for (i = 0; i < fdcount; i++) {
1620 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1622 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1624 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1626 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1628 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1632 /* event has finished */
1634 worker_returned(fd_worker);
1637 struct udev_device *dev;
1639 dev = udev_monitor_receive_device(monitor);
1641 if (event_queue_insert(dev) < 0)
1642 udev_device_unref(dev);
1645 /* start new events */
1646 if (!udev_list_is_empty(&event_list) && !udev_exit && !stop_exec_queue)
1647 event_queue_start(udev);
1650 struct signalfd_siginfo fdsi;
1653 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1654 if (size == sizeof(struct signalfd_siginfo))
1655 handle_signal(udev, fdsi.ssi_signo);
1658 /* we are shutting down, the events below are not handled anymore */
1662 /* device node and rules directory inotify watch */
1664 handle_inotify(udev);
1667 * This needs to be after the inotify handling, to make sure,
1668 * that the ping is send back after the possibly generated
1669 * "change" events by the inotify device node watch.
1671 * A single time we may receive a client connection which we need to
1672 * keep open to block the client. It will be closed right before we
1676 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1678 /* rules changed, set by inotify or a HUP signal */
1679 if (reload_config) {
1680 struct udev_rules *rules_new;
1682 worker_kill(udev, 0);
1683 rules_new = udev_rules_new(udev, resolve_names);
1684 if (rules_new != NULL) {
1685 udev_rules_unref(rules);
1692 udev_queue_export_cleanup(udev_queue_export);
1697 worker_list_cleanup(udev);
1698 event_queue_cleanup(udev, EVENT_UNDEF);
1699 udev_rules_unref(rules);
1702 if (worker_watch[READ_END] >= 0)
1703 close(worker_watch[READ_END]);
1704 if (worker_watch[WRITE_END] >= 0)
1705 close(worker_watch[WRITE_END]);
1706 udev_monitor_unref(monitor);
1707 udev_queue_export_unref(udev_queue_export);
1708 udev_ctrl_connection_unref(ctrl_conn);
1709 udev_ctrl_unref(udev_ctrl);
1710 udev_selinux_exit(udev);