2 * Copyright (C) 2004-2006 Kay Sievers <kay.sievers@vrfy.org>
3 * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation version 2 of the License.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
35 #include <sys/select.h>
37 #include <sys/types.h>
38 #include <sys/socket.h>
41 #include <sys/ioctl.h>
42 #include <linux/types.h>
43 #include <linux/netlink.h>
45 #include <sys/inotify.h>
49 #include "udev_rules.h"
51 #include "udev_selinux.h"
55 static void log_fn(struct udev *udev, int priority,
56 const char *file, int line, const char *fn,
57 const char *format, va_list args)
60 fprintf(stderr, "[%d] %s: ", (int) getpid(), fn);
61 vfprintf(stderr, format, args);
63 vsyslog(priority, format, args);
67 struct udevd_uevent_msg {
69 struct list_head node;
78 unsigned long long seqnum;
82 char *envp[UEVENT_NUM_ENVP+1];
86 static int debug_trace;
87 static struct udev_rules rules;
88 static int udevd_sock = -1;
89 static int uevent_netlink_sock = -1;
90 static int inotify_fd = -1;
93 static int signal_pipe[2] = {-1, -1};
94 static volatile int sigchilds_waiting;
95 static volatile int udev_exit;
96 static volatile int reload_config;
97 static int run_exec_q;
98 static int stop_exec_q;
99 static int max_childs;
100 static int max_childs_running;
101 static char udev_log_env[32];
103 static LIST_HEAD(exec_list);
104 static LIST_HEAD(running_list);
106 static void asmlinkage udev_event_sig_handler(int signum)
108 if (signum == SIGALRM)
112 static int udev_event_process(struct udevd_uevent_msg *msg)
114 struct sigaction act;
115 struct udevice *udevice;
119 /* set signal handlers */
120 memset(&act, 0x00, sizeof(act));
121 act.sa_handler = (void (*)(int)) udev_event_sig_handler;
122 sigemptyset (&act.sa_mask);
124 sigaction(SIGALRM, &act, NULL);
126 /* reset to default */
127 act.sa_handler = SIG_DFL;
128 sigaction(SIGINT, &act, NULL);
129 sigaction(SIGTERM, &act, NULL);
130 sigaction(SIGCHLD, &act, NULL);
131 sigaction(SIGHUP, &act, NULL);
133 /* trigger timeout to prevent hanging processes */
134 alarm(UDEV_EVENT_TIMEOUT);
136 /* reconstruct event environment from message */
137 for (i = 0; msg->envp[i]; i++)
138 putenv(msg->envp[i]);
140 udevice = udev_device_init(msg->udev);
143 strlcpy(udevice->action, msg->action, sizeof(udevice->action));
144 sysfs_device_set_values(udevice->udev, udevice->dev, msg->devpath, msg->subsystem, msg->driver);
145 udevice->devpath_old = msg->devpath_old;
146 udevice->devt = msg->devt;
148 retval = udev_device_event(&rules, udevice);
150 /* rules may change/disable the timeout */
151 if (udevice->event_timeout >= 0)
152 alarm(udevice->event_timeout);
154 /* run programs collected by RUN-key*/
155 if (retval == 0 && !udevice->ignore_device && udev_get_run(msg->udev))
156 retval = udev_rules_run(udevice);
158 udev_device_cleanup(udevice);
168 static void export_event_state(struct udevd_uevent_msg *msg, enum event_state state)
170 char filename[PATH_SIZE];
171 char filename_failed[PATH_SIZE];
174 /* location of queue file */
175 snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu", udev_get_dev_path(msg->udev), msg->seqnum);
177 /* location of failed file */
178 strlcpy(filename_failed, udev_get_dev_path(msg->udev), sizeof(filename_failed));
179 strlcat(filename_failed, "/", sizeof(filename_failed));
180 start = strlcat(filename_failed, ".udev/failed/", sizeof(filename_failed));
181 strlcat(filename_failed, msg->devpath, sizeof(filename_failed));
182 path_encode(&filename_failed[start], sizeof(filename_failed) - start);
186 unlink(filename_failed);
187 delete_path(msg->udev, filename_failed);
188 create_path(msg->udev, filename);
189 selinux_setfscreatecon(msg->udev, filename, NULL, S_IFLNK);
190 symlink(msg->devpath, filename);
191 selinux_resetfscreatecon(msg->udev);
194 if (msg->devpath_old != NULL) {
195 /* "move" event - rename failed file to current name, do not delete failed */
196 char filename_failed_old[PATH_SIZE];
198 strlcpy(filename_failed_old, udev_get_dev_path(msg->udev), sizeof(filename_failed_old));
199 strlcat(filename_failed_old, "/", sizeof(filename_failed_old));
200 start = strlcat(filename_failed_old, ".udev/failed/", sizeof(filename_failed_old));
201 strlcat(filename_failed_old, msg->devpath_old, sizeof(filename_failed_old));
202 path_encode(&filename_failed_old[start], sizeof(filename) - start);
204 if (rename(filename_failed_old, filename_failed) == 0)
205 info(msg->udev, "renamed devpath, moved failed state of '%s' to %s'\n",
206 msg->devpath_old, msg->devpath);
208 unlink(filename_failed);
209 delete_path(msg->udev, filename_failed);
213 delete_path(msg->udev, filename);
216 /* move failed event to the failed directory */
217 create_path(msg->udev, filename_failed);
218 rename(filename, filename_failed);
220 /* clean up possibly empty queue directory */
221 delete_path(msg->udev, filename);
228 static void msg_queue_delete(struct udevd_uevent_msg *msg)
230 list_del(&msg->node);
232 /* mark as failed, if "add" event returns non-zero */
233 if (msg->exitstatus && strcmp(msg->action, "add") == 0)
234 export_event_state(msg, EVENT_FAILED);
236 export_event_state(msg, EVENT_FINISHED);
241 static void udev_event_run(struct udevd_uevent_msg *msg)
250 close(uevent_netlink_sock);
254 close(signal_pipe[READ_END]);
255 close(signal_pipe[WRITE_END]);
257 logging_init("udevd-event");
258 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
260 retval = udev_event_process(msg);
261 info(msg->udev, "seq %llu finished with %i\n", msg->seqnum, retval);
268 err(msg->udev, "fork of child failed: %s\n", strerror(errno));
269 msg_queue_delete(msg);
272 /* get SIGCHLD in main loop */
273 info(msg->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n",
274 msg->seqnum, pid, msg->action, msg->subsystem, time(NULL) - msg->queue_time);
279 static void msg_queue_insert(struct udevd_uevent_msg *msg)
281 char filename[PATH_SIZE];
284 msg->queue_time = time(NULL);
286 export_event_state(msg, EVENT_QUEUED);
287 info(msg->udev, "seq %llu queued, '%s' '%s'\n", msg->seqnum, msg->action, msg->subsystem);
289 strlcpy(filename, udev_get_dev_path(msg->udev), sizeof(filename));
290 strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
291 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
296 len = sprintf(str, "%llu\n", msg->seqnum);
301 /* run one event after the other in debug mode */
303 list_add_tail(&msg->node, &running_list);
305 waitpid(msg->pid, NULL, 0);
306 msg_queue_delete(msg);
310 /* run all events with a timeout set immediately */
311 if (msg->timeout != 0) {
312 list_add_tail(&msg->node, &running_list);
317 list_add_tail(&msg->node, &exec_list);
321 static int mem_size_mb(void)
325 long int memsize = -1;
327 f = fopen("/proc/meminfo", "r");
331 while (fgets(buf, sizeof(buf), f) != NULL) {
334 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
335 memsize = value / 1024;
344 static int cpu_count(void)
350 f = fopen("/proc/stat", "r");
354 while (fgets(buf, sizeof(buf), f) != NULL) {
355 if (strncmp(buf, "cpu", 3) == 0 && isdigit(buf[3]))
365 static int running_processes(void)
371 f = fopen("/proc/stat", "r");
375 while (fgets(buf, sizeof(buf), f) != NULL) {
378 if (sscanf(buf, "procs_running %u", &value) == 1) {
388 /* return the number of process es in our session, count only until limit */
389 static int running_processes_in_session(pid_t session, int limit)
395 dir = opendir("/proc");
399 /* read process info from /proc */
400 for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
406 pid_t ppid, pgrp, sess;
409 if (!isdigit(dent->d_name[0]))
412 snprintf(procdir, sizeof(procdir), "/proc/%s/stat", dent->d_name);
413 procdir[sizeof(procdir)-1] = '\0';
415 f = open(procdir, O_RDONLY);
419 len = read(f, line, sizeof(line)-1);
427 /* skip ugly program name */
428 pos = strrchr(line, ')') + 2;
432 if (sscanf(pos, "%c %d %d %d ", &state, &ppid, &pgrp, &sess) != 4)
435 /* count only processes in our session */
439 /* count only running, no sleeping processes */
444 if (limit > 0 && running >= limit)
452 static int compare_devpath(const char *running, const char *waiting)
456 for (i = 0; i < PATH_SIZE; i++) {
457 /* identical device event found */
458 if (running[i] == '\0' && waiting[i] == '\0')
461 /* parent device event found */
462 if (running[i] == '\0' && waiting[i] == '/')
465 /* child device event found */
466 if (running[i] == '/' && waiting[i] == '\0')
469 /* no matching event */
470 if (running[i] != waiting[i])
477 /* lookup event for identical, parent, child, or physical device */
478 static int devpath_busy(struct udevd_uevent_msg *msg, int limit)
480 struct udevd_uevent_msg *loop_msg;
481 int childs_count = 0;
483 /* check exec-queue which may still contain delayed events we depend on */
484 list_for_each_entry(loop_msg, &exec_list, node) {
485 /* skip ourself and all later events */
486 if (loop_msg->seqnum >= msg->seqnum)
489 /* check our old name */
490 if (msg->devpath_old != NULL)
491 if (strcmp(loop_msg->devpath , msg->devpath_old) == 0)
494 /* check identical, parent, or child device event */
495 if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
496 dbg(msg->udev, "%llu, device event still pending %llu (%s)\n",
497 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
501 /* check for our major:minor number */
502 if (msg->devt && loop_msg->devt == msg->devt &&
503 strcmp(msg->subsystem, loop_msg->subsystem) == 0) {
504 dbg(msg->udev, "%llu, device event still pending %llu (%d:%d)\n", msg->seqnum,
505 loop_msg->seqnum, major(loop_msg->devt), minor(loop_msg->devt));
509 /* check physical device event (special case of parent) */
510 if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
511 if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
512 dbg(msg->udev, "%llu, physical device event still pending %llu (%s)\n",
513 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
518 /* check run queue for still running events */
519 list_for_each_entry(loop_msg, &running_list, node) {
520 if (limit && childs_count++ > limit) {
521 dbg(msg->udev, "%llu, maximum number (%i) of childs reached\n", msg->seqnum, childs_count);
525 /* check our old name */
526 if (msg->devpath_old != NULL)
527 if (strcmp(loop_msg->devpath , msg->devpath_old) == 0)
530 /* check identical, parent, or child device event */
531 if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
532 dbg(msg->udev, "%llu, device event still running %llu (%s)\n",
533 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
537 /* check for our major:minor number */
538 if (msg->devt && loop_msg->devt == msg->devt &&
539 strcmp(msg->subsystem, loop_msg->subsystem) == 0) {
540 dbg(msg->udev, "%llu, device event still running %llu (%d:%d)\n", msg->seqnum,
541 loop_msg->seqnum, major(loop_msg->devt), minor(loop_msg->devt));
545 /* check physical device event (special case of parent) */
546 if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
547 if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
548 dbg(msg->udev, "%llu, physical device event still running %llu (%s)\n",
549 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
556 /* serializes events for the identical and parent and child devices */
557 static void msg_queue_manager(struct udev *udev)
559 struct udevd_uevent_msg *loop_msg;
560 struct udevd_uevent_msg *tmp_msg;
563 if (list_empty(&exec_list))
566 running = running_processes();
567 dbg(udev, "%d processes runnning on system\n", running);
569 running = max_childs_running;
571 list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, node) {
572 /* check running processes in our session and possibly throttle */
573 if (running >= max_childs_running) {
574 running = running_processes_in_session(sid, max_childs_running+10);
575 dbg(udev, "at least %d processes running in session\n", running);
576 if (running >= max_childs_running) {
577 dbg(udev, "delay seq %llu, too many processes already running\n", loop_msg->seqnum);
582 /* serialize and wait for parent or child events */
583 if (devpath_busy(loop_msg, max_childs) != 0) {
584 dbg(udev, "delay seq %llu (%s)\n", loop_msg->seqnum, loop_msg->devpath);
588 /* move event to run list */
589 list_move_tail(&loop_msg->node, &running_list);
590 udev_event_run(loop_msg);
592 dbg(udev, "moved seq %llu to running list\n", loop_msg->seqnum);
596 static struct udevd_uevent_msg *get_msg_from_envbuf(struct udev *udev, const char *buf, int buf_size)
600 struct udevd_uevent_msg *msg;
601 char *physdevdriver_key = NULL;
605 msg = malloc(sizeof(struct udevd_uevent_msg) + buf_size);
608 memset(msg, 0x00, sizeof(struct udevd_uevent_msg) + buf_size);
611 /* copy environment buffer and reconstruct envp */
612 memcpy(msg->envbuf, buf, buf_size);
614 for (i = 0; (bufpos < buf_size) && (i < UEVENT_NUM_ENVP-2); i++) {
618 key = &msg->envbuf[bufpos];
619 keylen = strlen(key);
621 bufpos += keylen + 1;
622 dbg(udev, "add '%s' to msg.envp[%i]\n", msg->envp[i], i);
624 /* remember some keys for further processing */
625 if (strncmp(key, "ACTION=", 7) == 0)
626 msg->action = &key[7];
627 else if (strncmp(key, "DEVPATH=", 8) == 0)
628 msg->devpath = &key[8];
629 else if (strncmp(key, "SUBSYSTEM=", 10) == 0)
630 msg->subsystem = &key[10];
631 else if (strncmp(key, "DRIVER=", 7) == 0)
632 msg->driver = &key[7];
633 else if (strncmp(key, "SEQNUM=", 7) == 0)
634 msg->seqnum = strtoull(&key[7], NULL, 10);
635 else if (strncmp(key, "DEVPATH_OLD=", 12) == 0)
636 msg->devpath_old = &key[12];
637 else if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
638 msg->physdevpath = &key[12];
639 else if (strncmp(key, "PHYSDEVDRIVER=", 14) == 0)
640 physdevdriver_key = key;
641 else if (strncmp(key, "MAJOR=", 6) == 0)
642 maj = strtoull(&key[6], NULL, 10);
643 else if (strncmp(key, "MINOR=", 6) == 0)
644 min = strtoull(&key[6], NULL, 10);
645 else if (strncmp(key, "TIMEOUT=", 8) == 0)
646 msg->timeout = strtoull(&key[8], NULL, 10);
648 msg->devt = makedev(maj, min);
649 msg->envp[i++] = "UDEVD_EVENT=1";
651 if (msg->driver == NULL && msg->physdevpath == NULL && physdevdriver_key != NULL) {
652 /* for older kernels DRIVER is empty for a bus device, export PHYSDEVDRIVER as DRIVER */
653 msg->envp[i++] = &physdevdriver_key[7];
654 msg->driver = &physdevdriver_key[14];
659 if (msg->devpath == NULL || msg->action == NULL) {
660 info(udev, "DEVPATH or ACTION missing, ignore message\n");
667 /* receive the udevd message from userspace */
668 static void get_ctrl_msg(struct udev *udev)
670 struct udevd_ctrl_msg ctrl_msg;
673 struct cmsghdr *cmsg;
676 char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
679 memset(&ctrl_msg, 0x00, sizeof(struct udevd_ctrl_msg));
680 iov.iov_base = &ctrl_msg;
681 iov.iov_len = sizeof(struct udevd_ctrl_msg);
683 memset(&smsg, 0x00, sizeof(struct msghdr));
686 smsg.msg_control = cred_msg;
687 smsg.msg_controllen = sizeof(cred_msg);
689 size = recvmsg(udevd_sock, &smsg, 0);
692 err(udev, "unable to receive user udevd message: %s\n", strerror(errno));
695 cmsg = CMSG_FIRSTHDR(&smsg);
696 cred = (struct ucred *) CMSG_DATA(cmsg);
698 if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
699 err(udev, "no sender credentials received, message ignored\n");
703 if (cred->uid != 0) {
704 err(udev, "sender uid=%i, message ignored\n", cred->uid);
708 if (strncmp(ctrl_msg.magic, UDEVD_CTRL_MAGIC, sizeof(UDEVD_CTRL_MAGIC)) != 0 ) {
709 err(udev, "message magic '%s' doesn't match, ignore it\n", ctrl_msg.magic);
713 switch (ctrl_msg.type) {
715 pos = strchr(ctrl_msg.buf, '=');
717 err(udev, "wrong key format '%s'\n", ctrl_msg.buf);
721 if (pos[1] == '\0') {
722 info(udev, "udevd message (ENV) received, unset '%s'\n", ctrl_msg.buf);
723 unsetenv(ctrl_msg.buf);
725 info(udev, "udevd message (ENV) received, set '%s=%s'\n", ctrl_msg.buf, &pos[1]);
726 setenv(ctrl_msg.buf, &pos[1], 1);
729 case UDEVD_CTRL_STOP_EXEC_QUEUE:
730 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
733 case UDEVD_CTRL_START_EXEC_QUEUE:
734 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
736 msg_queue_manager(udev);
738 case UDEVD_CTRL_SET_LOG_LEVEL:
739 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", ctrl_msg.intval);
740 udev_set_log_priority(udev, ctrl_msg.intval);
741 sprintf(udev_log_env, "UDEV_LOG=%i", udev_get_log_priority(udev));
742 putenv(udev_log_env);
744 case UDEVD_CTRL_SET_MAX_CHILDS:
745 info(udev, "udevd message (UDEVD_SET_MAX_CHILDS) received, max_childs=%i\n", ctrl_msg.intval);
746 max_childs = ctrl_msg.intval;
748 case UDEVD_CTRL_SET_MAX_CHILDS_RUNNING:
749 info(udev, "udevd message (UDEVD_SET_MAX_CHILDS_RUNNING) received, max_childs_running=%i\n", ctrl_msg.intval);
750 max_childs_running = ctrl_msg.intval;
752 case UDEVD_CTRL_RELOAD_RULES:
753 info(udev, "udevd message (RELOAD_RULES) received\n");
757 err(udev, "unknown control message type\n");
761 /* receive the kernel user event message and do some sanity checks */
762 static struct udevd_uevent_msg *get_netlink_msg(struct udev *udev)
764 struct udevd_uevent_msg *msg;
767 static char buffer[UEVENT_BUFFER_SIZE+512];
770 size = recv(uevent_netlink_sock, &buffer, sizeof(buffer), 0);
773 err(udev, "unable to receive kernel netlink message: %s\n", strerror(errno));
777 if ((size_t)size > sizeof(buffer)-1)
778 size = sizeof(buffer)-1;
780 dbg(udev, "uevent_size=%zi\n", size);
782 /* start of event payload */
783 bufpos = strlen(buffer)+1;
784 msg = get_msg_from_envbuf(udev, &buffer[bufpos], size-bufpos);
788 /* validate message */
789 pos = strchr(buffer, '@');
791 err(udev, "invalid uevent '%s'\n", buffer);
797 if (msg->action == NULL) {
798 info(udev, "no ACTION in payload found, skip event '%s'\n", buffer);
803 if (strcmp(msg->action, buffer) != 0) {
804 err(udev, "ACTION in payload does not match uevent, skip event '%s'\n", buffer);
812 static void asmlinkage sig_handler(int signum)
820 /* set flag, then write to pipe if needed */
821 sigchilds_waiting = 1;
828 /* write to pipe, which will wakeup select() in our mainloop */
829 write(signal_pipe[WRITE_END], "", 1);
832 static void udev_done(int pid, int exitstatus)
834 /* find msg associated with pid and delete it */
835 struct udevd_uevent_msg *msg;
837 list_for_each_entry(msg, &running_list, node) {
838 if (msg->pid == pid) {
839 info(msg->udev, "seq %llu, pid [%d] exit with %i, %ld seconds old\n", msg->seqnum, msg->pid,
840 exitstatus, time(NULL) - msg->queue_time);
841 msg->exitstatus = exitstatus;
842 msg_queue_delete(msg);
844 /* there may be events waiting with the same devpath */
851 static void reap_sigchilds(void)
857 pid = waitpid(-1, &status, WNOHANG);
860 if (WIFEXITED(status))
861 status = WEXITSTATUS(status);
862 else if (WIFSIGNALED(status))
863 status = WTERMSIG(status) + 128;
866 udev_done(pid, status);
870 static int init_udevd_socket(struct udev *udev)
872 struct sockaddr_un saddr;
874 const int feature_on = 1;
877 memset(&saddr, 0x00, sizeof(saddr));
878 saddr.sun_family = AF_LOCAL;
879 strcpy(saddr.sun_path, UDEVD_CTRL_SOCK_PATH);
880 addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(saddr.sun_path);
881 /* translate leading '@' to abstract namespace */
882 if (saddr.sun_path[0] == '@')
883 saddr.sun_path[0] = '\0';
885 udevd_sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
886 if (udevd_sock == -1) {
887 err(udev, "error getting socket: %s\n", strerror(errno));
891 /* the bind takes care of ensuring only one copy running */
892 retval = bind(udevd_sock, (struct sockaddr *) &saddr, addrlen);
894 err(udev, "bind failed: %s\n", strerror(errno));
900 /* enable receiving of the sender credentials */
901 setsockopt(udevd_sock, SOL_SOCKET, SO_PASSCRED, &feature_on, sizeof(feature_on));
906 static int init_uevent_netlink_sock(struct udev *udev)
908 struct sockaddr_nl snl;
909 const int buffersize = 16 * 1024 * 1024;
912 memset(&snl, 0x00, sizeof(struct sockaddr_nl));
913 snl.nl_family = AF_NETLINK;
914 snl.nl_pid = getpid();
917 uevent_netlink_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
918 if (uevent_netlink_sock == -1) {
919 err(udev, "error getting socket: %s\n", strerror(errno));
923 /* set receive buffersize */
924 setsockopt(uevent_netlink_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
926 retval = bind(uevent_netlink_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
928 err(udev, "bind failed: %s\n", strerror(errno));
929 close(uevent_netlink_sock);
930 uevent_netlink_sock = -1;
936 static void export_initial_seqnum(struct udev *udev)
938 char filename[PATH_SIZE];
943 strlcpy(filename, udev_get_sys_path(udev), sizeof(filename));
944 strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename));
945 fd = open(filename, O_RDONLY);
947 len = read(fd, seqnum, sizeof(seqnum)-1);
951 strcpy(seqnum, "0\n");
954 strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
955 strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
956 create_path(udev, filename);
957 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
959 write(fd, seqnum, len);
964 int main(int argc, char *argv[])
969 struct sigaction act;
973 static const struct option options[] = {
974 { "daemon", 0, NULL, 'd' },
975 { "debug-trace", 0, NULL, 't' },
976 { "debug", 0, NULL, 'D' },
977 { "help", 0, NULL, 'h' },
978 { "version", 0, NULL, 'V' },
988 logging_init("udevd");
989 udev_set_log_fn(udev, log_fn);
992 dbg(udev, "version %s\n", VERSION);
997 option = getopt_long(argc, argv, "dDthV", options, NULL);
1010 if (udev_get_log_priority(udev) < LOG_INFO)
1011 udev_set_log_priority(udev, LOG_INFO);
1014 printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] [--version]\n");
1017 printf("%s\n", VERSION);
1024 if (getuid() != 0) {
1025 fprintf(stderr, "root privileges required\n");
1026 err(udev, "root privileges required\n");
1030 /* make sure std{in,out,err} fd's are in a sane state */
1031 fd = open("/dev/null", O_RDWR);
1033 fprintf(stderr, "cannot open /dev/null\n");
1034 err(udev, "cannot open /dev/null\n");
1036 if (fd > STDIN_FILENO)
1037 dup2(fd, STDIN_FILENO);
1038 if (write(STDOUT_FILENO, 0, 0) < 0)
1039 dup2(fd, STDOUT_FILENO);
1040 if (write(STDERR_FILENO, 0, 0) < 0)
1041 dup2(fd, STDERR_FILENO);
1043 /* init sockets to receive events */
1044 if (init_udevd_socket(udev) < 0) {
1045 if (errno == EADDRINUSE) {
1046 fprintf(stderr, "another udev daemon already running\n");
1047 err(udev, "another udev daemon already running\n");
1050 fprintf(stderr, "error initializing udevd socket\n");
1051 err(udev, "error initializing udevd socket\n");
1057 if (init_uevent_netlink_sock(udev) < 0) {
1058 fprintf(stderr, "error initializing netlink socket\n");
1059 err(udev, "error initializing netlink socket\n");
1064 /* setup signal handler pipe */
1065 retval = pipe(signal_pipe);
1067 err(udev, "error getting pipes: %s\n", strerror(errno));
1071 retval = fcntl(signal_pipe[READ_END], F_GETFL, 0);
1073 err(udev, "error fcntl on read pipe: %s\n", strerror(errno));
1076 retval = fcntl(signal_pipe[READ_END], F_SETFL, retval | O_NONBLOCK);
1078 err(udev, "error fcntl on read pipe: %s\n", strerror(errno));
1082 retval = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
1084 err(udev, "error fcntl on write pipe: %s\n", strerror(errno));
1087 retval = fcntl(signal_pipe[WRITE_END], F_SETFL, retval | O_NONBLOCK);
1089 err(udev, "error fcntl on write pipe: %s\n", strerror(errno));
1093 /* parse the rules and keep them in memory */
1095 udev_rules_init(udev, &rules, 1);
1097 export_initial_seqnum(udev);
1105 dbg(udev, "daemonized fork running\n");
1108 err(udev, "fork of daemon failed: %s\n", strerror(errno));
1112 dbg(udev, "child [%u] running, parent exits\n", pid);
1118 /* redirect std{out,err} fd's */
1120 dup2(fd, STDOUT_FILENO);
1121 dup2(fd, STDERR_FILENO);
1122 if (fd > STDERR_FILENO)
1125 /* set scheduling priority for the daemon */
1126 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
1131 /* become session leader */
1133 dbg(udev, "our session is %d\n", sid);
1135 /* OOM_DISABLE == -17 */
1136 fd = open("/proc/self/oom_adj", O_RDWR);
1138 err(udev, "error disabling OOM: %s\n", strerror(errno));
1140 write(fd, "-17", 3);
1144 fd = open("/dev/kmsg", O_WRONLY);
1146 const char *str = "<6>udevd version " VERSION " started\n";
1148 write(fd, str, strlen(str));
1152 /* set signal handlers */
1153 memset(&act, 0x00, sizeof(struct sigaction));
1154 act.sa_handler = (void (*)(int)) sig_handler;
1155 sigemptyset(&act.sa_mask);
1156 act.sa_flags = SA_RESTART;
1157 sigaction(SIGINT, &act, NULL);
1158 sigaction(SIGTERM, &act, NULL);
1159 sigaction(SIGCHLD, &act, NULL);
1160 sigaction(SIGHUP, &act, NULL);
1162 /* watch rules directory */
1163 inotify_fd = inotify_init();
1164 if (inotify_fd >= 0) {
1165 if (udev_get_rules_path(udev) != NULL) {
1166 inotify_add_watch(inotify_fd, udev_get_rules_path(udev),
1167 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1169 char filename[PATH_MAX];
1171 inotify_add_watch(inotify_fd, UDEV_PREFIX "/lib/udev/rules.d",
1172 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1173 inotify_add_watch(inotify_fd, SYSCONFDIR "/udev/rules.d",
1174 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1176 /* watch dynamic rules directory */
1177 strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
1178 strlcat(filename, "/.udev/rules.d", sizeof(filename));
1179 inotify_add_watch(inotify_fd, filename,
1180 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1182 } else if (errno == ENOSYS)
1183 err(udev, "the kernel does not support inotify, udevd can't monitor rules file changes\n");
1185 err(udev, "inotify_init failed: %s\n", strerror(errno));
1187 /* maximum limit of forked childs */
1188 value = getenv("UDEVD_MAX_CHILDS");
1190 max_childs = strtoul(value, NULL, 10);
1192 int memsize = mem_size_mb();
1194 max_childs = 128 + (memsize / 4);
1196 max_childs = UDEVD_MAX_CHILDS;
1198 info(udev, "initialize max_childs to %u\n", max_childs);
1200 /* start to throttle forking if maximum number of _running_ childs is reached */
1201 value = getenv("UDEVD_MAX_CHILDS_RUNNING");
1203 max_childs_running = strtoull(value, NULL, 10);
1205 int cpus = cpu_count();
1207 max_childs_running = 8 + (8 * cpus);
1209 max_childs_running = UDEVD_MAX_CHILDS_RUNNING;
1211 info(udev, "initialize max_childs_running to %u\n", max_childs_running);
1213 /* clear environment for forked event processes */
1216 /* export log_priority , as called programs may want to follow that setting */
1217 sprintf(udev_log_env, "UDEV_LOG=%i", udev_get_log_priority(udev));
1218 putenv(udev_log_env);
1223 maxfd = UDEV_MAX(maxfd, uevent_netlink_sock);
1224 maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
1225 maxfd = UDEV_MAX(maxfd, inotify_fd);
1227 while (!udev_exit) {
1228 struct udevd_uevent_msg *msg;
1232 FD_SET(signal_pipe[READ_END], &readfds);
1233 FD_SET(udevd_sock, &readfds);
1234 FD_SET(uevent_netlink_sock, &readfds);
1235 if (inotify_fd >= 0)
1236 FD_SET(inotify_fd, &readfds);
1238 fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
1241 err(udev, "error in select: %s\n", strerror(errno));
1245 /* get control message */
1246 if (FD_ISSET(udevd_sock, &readfds))
1249 /* get netlink message */
1250 if (FD_ISSET(uevent_netlink_sock, &readfds)) {
1251 msg = get_netlink_msg(udev);
1253 msg_queue_insert(msg);
1256 /* received a signal, clear our notification pipe */
1257 if (FD_ISSET(signal_pipe[READ_END], &readfds)) {
1260 read(signal_pipe[READ_END], &buf, sizeof(buf));
1263 /* rules directory inotify watch */
1264 if ((inotify_fd >= 0) && FD_ISSET(inotify_fd, &readfds)) {
1267 /* discard all possible events, we can just reload the config */
1268 if ((ioctl(inotify_fd, FIONREAD, &nbytes) == 0) && nbytes > 0) {
1272 buf = malloc(nbytes);
1274 err(udev, "error getting buffer for inotify, disable watching\n");
1278 read(inotify_fd, buf, nbytes);
1283 /* rules changed, set by inotify or a HUP signal */
1284 if (reload_config) {
1286 udev_rules_cleanup(&rules);
1287 udev_rules_init(udev, &rules, 1);
1290 /* forked child has returned */
1291 if (sigchilds_waiting) {
1292 sigchilds_waiting = 0;
1299 msg_queue_manager(udev);
1305 udev_rules_cleanup(&rules);
1309 if (signal_pipe[READ_END] >= 0)
1310 close(signal_pipe[READ_END]);
1311 if (signal_pipe[WRITE_END] >= 0)
1312 close(signal_pipe[WRITE_END]);
1314 if (udevd_sock >= 0)
1316 if (inotify_fd >= 0)
1318 if (uevent_netlink_sock >= 0)
1319 close(uevent_netlink_sock);