2 * Copyright (C) 2003-2010 Kay Sievers <kay.sievers@vrfy.org>
4 * This program is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
28 #include <sys/ioctl.h>
29 #include <sys/prctl.h>
31 #include <sys/epoll.h>
33 #include <sys/socket.h>
34 #include <sys/signalfd.h>
35 #include <linux/sockios.h>
39 struct udev_event *udev_event_new(struct udev_device *dev)
41 struct udev *udev = udev_device_get_udev(dev);
42 struct udev_event *event;
44 event = calloc(1, sizeof(struct udev_event));
49 udev_list_init(udev, &event->run_list, false);
50 event->fd_signal = -1;
51 event->birth_usec = now_usec();
52 event->timeout_usec = 30 * 1000 * 1000;
56 void udev_event_unref(struct udev_event *event)
60 udev_list_cleanup(&event->run_list);
61 free(event->program_result);
66 size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size)
68 struct udev_device *dev = event->dev;
88 static const struct subst_map {
93 { .name = "devnode", .fmt = 'N', .type = SUBST_DEVNODE },
94 { .name = "tempnode", .fmt = 'N', .type = SUBST_DEVNODE },
95 { .name = "attr", .fmt = 's', .type = SUBST_ATTR },
96 { .name = "sysfs", .fmt = 's', .type = SUBST_ATTR },
97 { .name = "env", .fmt = 'E', .type = SUBST_ENV },
98 { .name = "kernel", .fmt = 'k', .type = SUBST_KERNEL },
99 { .name = "number", .fmt = 'n', .type = SUBST_KERNEL_NUMBER },
100 { .name = "driver", .fmt = 'd', .type = SUBST_DRIVER },
101 { .name = "devpath", .fmt = 'p', .type = SUBST_DEVPATH },
102 { .name = "id", .fmt = 'b', .type = SUBST_ID },
103 { .name = "major", .fmt = 'M', .type = SUBST_MAJOR },
104 { .name = "minor", .fmt = 'm', .type = SUBST_MINOR },
105 { .name = "result", .fmt = 'c', .type = SUBST_RESULT },
106 { .name = "parent", .fmt = 'P', .type = SUBST_PARENT },
107 { .name = "name", .fmt = 'D', .type = SUBST_NAME },
108 { .name = "links", .fmt = 'L', .type = SUBST_LINKS },
109 { .name = "root", .fmt = 'r', .type = SUBST_ROOT },
110 { .name = "sys", .fmt = 'S', .type = SUBST_SYS },
121 enum subst_type type = SUBST_UNKNOWN;
122 char attrbuf[UTIL_PATH_SIZE];
125 while (from[0] != '\0') {
126 if (from[0] == '$') {
127 /* substitute named variable */
130 if (from[1] == '$') {
135 for (i = 0; i < ARRAY_SIZE(map); i++) {
136 if (strncmp(&from[1], map[i].name, strlen(map[i].name)) == 0) {
138 from += strlen(map[i].name)+1;
142 } else if (from[0] == '%') {
143 /* substitute format char */
146 if (from[1] == '%') {
151 for (i = 0; i < ARRAY_SIZE(map); i++) {
152 if (from[1] == map[i].fmt) {
171 /* extract possible $format{attr} */
172 if (from[0] == '{') {
176 for (i = 0; from[i] != '}'; i++) {
177 if (from[i] == '\0') {
178 log_error("missing closing brace for format '%s'\n", src);
182 if (i >= sizeof(attrbuf))
184 memcpy(attrbuf, from, i);
194 l = util_strpcpy(&s, l, udev_device_get_devpath(dev));
197 l = util_strpcpy(&s, l, udev_device_get_sysname(dev));
199 case SUBST_KERNEL_NUMBER:
200 if (udev_device_get_sysnum(dev) == NULL)
202 l = util_strpcpy(&s, l, udev_device_get_sysnum(dev));
205 if (event->dev_parent == NULL)
207 l = util_strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
212 if (event->dev_parent == NULL)
215 driver = udev_device_get_driver(event->dev_parent);
218 l = util_strpcpy(&s, l, driver);
222 char num[UTIL_PATH_SIZE];
224 sprintf(num, "%d", major(udev_device_get_devnum(dev)));
225 l = util_strpcpy(&s, l, num);
229 char num[UTIL_PATH_SIZE];
231 sprintf(num, "%d", minor(udev_device_get_devnum(dev)));
232 l = util_strpcpy(&s, l, num);
239 if (event->program_result == NULL)
241 /* get part part of the result string */
244 i = strtoul(attr, &rest, 10);
246 char result[UTIL_PATH_SIZE];
247 char tmp[UTIL_PATH_SIZE];
250 util_strscpy(result, sizeof(result), event->program_result);
253 while (cpos[0] != '\0' && !isspace(cpos[0]))
255 while (isspace(cpos[0]))
259 log_error("requested part of result string not found\n");
262 util_strscpy(tmp, sizeof(tmp), cpos);
263 /* %{2+}c copies the whole string from the second part on */
264 if (rest[0] != '+') {
265 cpos = strchr(tmp, ' ');
269 l = util_strpcpy(&s, l, tmp);
271 l = util_strpcpy(&s, l, event->program_result);
276 const char *value = NULL;
277 char vbuf[UTIL_NAME_SIZE];
282 log_error("missing file parameter for attr\n");
286 /* try to read the value specified by "[dmi/id]product_name" */
287 if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0)
290 /* try to read the attribute the device */
292 value = udev_device_get_sysattr_value(event->dev, attr);
294 /* try to read the attribute of the parent device, other matches have selected */
295 if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev)
296 value = udev_device_get_sysattr_value(event->dev_parent, attr);
301 /* strip trailing whitespace, and replace unwanted characters */
303 util_strscpy(vbuf, sizeof(vbuf), value);
305 while (len > 0 && isspace(vbuf[--len]))
307 count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
309 log_debug("%i character(s) replaced\n" , count);
310 l = util_strpcpy(&s, l, vbuf);
314 struct udev_device *dev_parent;
317 dev_parent = udev_device_get_parent(event->dev);
318 if (dev_parent == NULL)
320 devnode = udev_device_get_devnode(dev_parent);
321 if (devnode != NULL) {
322 size_t devlen = strlen(udev_get_dev_path(event->udev))+1;
324 l = util_strpcpy(&s, l, &devnode[devlen]);
329 if (udev_device_get_devnode(dev) != NULL)
330 l = util_strpcpy(&s, l, udev_device_get_devnode(dev));
333 if (event->name != NULL) {
334 l = util_strpcpy(&s, l, event->name);
335 } else if (udev_device_get_devnode(dev) != NULL) {
336 size_t devlen = strlen(udev_get_dev_path(event->udev))+1;
338 l = util_strpcpy(&s, l, &udev_device_get_devnode(dev)[devlen]);
340 l = util_strpcpy(&s, l, udev_device_get_sysname(dev));
345 size_t devlen = strlen(udev_get_dev_path(event->udev))+1;
346 struct udev_list_entry *list_entry;
348 list_entry = udev_device_get_devlinks_list_entry(dev);
349 if (list_entry == NULL)
351 l = util_strpcpy(&s, l, &udev_list_entry_get_name(list_entry)[devlen]);
352 udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
353 l = util_strpcpyl(&s, l, " ", &udev_list_entry_get_name(list_entry)[devlen], NULL);
357 l = util_strpcpy(&s, l, udev_get_dev_path(event->udev));
360 l = util_strpcpy(&s, l, udev_get_sys_path(event->udev));
368 value = udev_device_get_property_value(event->dev, attr);
371 l = util_strpcpy(&s, l, value);
375 log_error("unknown substitution type=%i\n", type);
385 static int spawn_exec(struct udev_event *event,
386 const char *cmd, char *const argv[], char **envp, const sigset_t *sigmask,
387 int fd_stdout, int fd_stderr)
389 struct udev *udev = event->udev;
393 /* discard child output or connect to pipe */
394 fd = open("/dev/null", O_RDWR);
396 dup2(fd, STDIN_FILENO);
398 dup2(fd, STDOUT_FILENO);
400 dup2(fd, STDERR_FILENO);
403 log_error("open /dev/null failed: %m\n");
406 /* connect pipes to std{out,err} */
407 if (fd_stdout >= 0) {
408 dup2(fd_stdout, STDOUT_FILENO);
411 if (fd_stderr >= 0) {
412 dup2(fd_stderr, STDERR_FILENO);
416 /* terminate child in case parent goes away */
417 prctl(PR_SET_PDEATHSIG, SIGTERM);
419 /* restore original udev sigmask before exec */
421 sigprocmask(SIG_SETMASK, sigmask, NULL);
423 execve(argv[0], argv, envp);
427 log_error("failed to execute '%s' '%s': %m\n", argv[0], cmd);
431 static void spawn_read(struct udev_event *event,
433 int fd_stdout, int fd_stderr,
434 char *result, size_t ressize)
436 struct udev *udev = event->udev;
439 struct epoll_event ep_outpipe, ep_errpipe;
441 /* read from child if requested */
442 if (fd_stdout < 0 && fd_stderr < 0)
445 fd_ep = epoll_create1(EPOLL_CLOEXEC);
447 log_error("error creating epoll fd: %m\n");
451 if (fd_stdout >= 0) {
452 memset(&ep_outpipe, 0, sizeof(struct epoll_event));
453 ep_outpipe.events = EPOLLIN;
454 ep_outpipe.data.ptr = &fd_stdout;
455 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe) < 0) {
456 log_error("fail to add fd to epoll: %m\n");
461 if (fd_stderr >= 0) {
462 memset(&ep_errpipe, 0, sizeof(struct epoll_event));
463 ep_errpipe.events = EPOLLIN;
464 ep_errpipe.data.ptr = &fd_stderr;
465 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe) < 0) {
466 log_error("fail to add fd to epoll: %m\n");
471 /* read child output */
472 while (fd_stdout >= 0 || fd_stderr >= 0) {
475 struct epoll_event ev[4];
478 if (event->timeout_usec > 0) {
479 unsigned long long age_usec;
481 age_usec = now_usec() - event->birth_usec;
482 if (age_usec >= event->timeout_usec) {
483 log_error("timeout '%s'\n", cmd);
486 timeout = ((event->timeout_usec - age_usec) / 1000) + 1000;
491 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
495 log_error("failed to poll: %m\n");
499 log_error("timeout '%s'\n", cmd);
503 for (i = 0; i < fdcount; i++) {
504 int *fd = (int *)ev[i].data.ptr;
506 if (ev[i].events & EPOLLIN) {
510 count = read(*fd, buf, sizeof(buf)-1);
515 /* store stdout result */
516 if (result != NULL && *fd == fd_stdout) {
517 if (respos + count < ressize) {
518 memcpy(&result[respos], buf, count);
521 log_error("'%s' ressize %zd too short\n", cmd, ressize);
525 /* log debug output only if we watch stderr */
526 if (fd_stderr >= 0) {
531 while ((line = strsep(&pos, "\n"))) {
532 if (pos != NULL || line[0] != '\0')
533 log_debug("'%s'(%s) '%s'\n", cmd, *fd == fd_stdout ? "out" : "err" , line);
536 } else if (ev[i].events & EPOLLHUP) {
537 if (epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL) < 0) {
538 log_error("failed to remove fd from epoll: %m\n");
546 /* return the child's stdout string */
548 result[respos] = '\0';
554 static int spawn_wait(struct udev_event *event, const char *cmd, pid_t pid)
556 struct udev *udev = event->udev;
557 struct pollfd pfd[1];
560 pfd[0].events = POLLIN;
561 pfd[0].fd = event->fd_signal;
567 if (event->timeout_usec > 0) {
568 unsigned long long age_usec;
570 age_usec = now_usec() - event->birth_usec;
571 if (age_usec >= event->timeout_usec)
574 timeout = ((event->timeout_usec - age_usec) / 1000) + 1000;
579 fdcount = poll(pfd, 1, timeout);
584 log_error("failed to poll: %m\n");
588 log_error("timeout: killing '%s' [%u]\n", cmd, pid);
592 if (pfd[0].revents & POLLIN) {
593 struct signalfd_siginfo fdsi;
597 size = read(event->fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
598 if (size != sizeof(struct signalfd_siginfo))
601 switch (fdsi.ssi_signo) {
603 event->sigterm = true;
606 if (waitpid(pid, &status, WNOHANG) < 0)
608 if (WIFEXITED(status)) {
609 log_debug("'%s' [%u] exit with return code %i\n", cmd, pid, WEXITSTATUS(status));
610 if (WEXITSTATUS(status) != 0)
612 } else if (WIFSIGNALED(status)) {
613 log_error("'%s' [%u] terminated by signal %i (%s)\n", cmd, pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
615 } else if (WIFSTOPPED(status)) {
616 log_error("'%s' [%u] stopped\n", cmd, pid);
618 } else if (WIFCONTINUED(status)) {
619 log_error("'%s' [%u] continued\n", cmd, pid);
622 log_error("'%s' [%u] exit with status 0x%04x\n", cmd, pid, status);
634 int udev_build_argv(struct udev *udev, char *cmd, int *argc, char *argv[])
639 if (strchr(cmd, ' ') == NULL) {
645 while (pos != NULL && pos[0] != '\0') {
646 if (pos[0] == '\'') {
647 /* do not separate quotes */
649 argv[i] = strsep(&pos, "\'");
651 while (pos[0] == ' ')
654 argv[i] = strsep(&pos, " ");
656 while (pos[0] == ' ')
668 int udev_event_spawn(struct udev_event *event,
669 const char *cmd, char **envp, const sigset_t *sigmask,
670 char *result, size_t ressize)
672 struct udev *udev = event->udev;
673 int outpipe[2] = {-1, -1};
674 int errpipe[2] = {-1, -1};
676 char arg[UTIL_PATH_SIZE];
678 char program[UTIL_PATH_SIZE];
681 util_strscpy(arg, sizeof(arg), cmd);
682 udev_build_argv(event->udev, arg, NULL, argv);
684 /* pipes from child to parent */
685 if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) {
686 if (pipe2(outpipe, O_NONBLOCK) != 0) {
688 log_error("pipe failed: %m\n");
692 if (udev_get_log_priority(udev) >= LOG_INFO) {
693 if (pipe2(errpipe, O_NONBLOCK) != 0) {
695 log_error("pipe failed: %m\n");
700 /* allow programs in /usr/lib/udev/ to be called without the path */
701 if (argv[0][0] != '/') {
702 util_strscpyl(program, sizeof(program), UDEVLIBEXECDIR "/", argv[0], NULL);
709 /* child closes parent's ends of pipes */
710 if (outpipe[READ_END] >= 0) {
711 close(outpipe[READ_END]);
712 outpipe[READ_END] = -1;
714 if (errpipe[READ_END] >= 0) {
715 close(errpipe[READ_END]);
716 errpipe[READ_END] = -1;
719 log_debug("starting '%s'\n", cmd);
721 err = spawn_exec(event, cmd, argv, envp, sigmask,
722 outpipe[WRITE_END], errpipe[WRITE_END]);
726 log_error("fork of '%s' failed: %m\n", cmd);
730 /* parent closed child's ends of pipes */
731 if (outpipe[WRITE_END] >= 0) {
732 close(outpipe[WRITE_END]);
733 outpipe[WRITE_END] = -1;
735 if (errpipe[WRITE_END] >= 0) {
736 close(errpipe[WRITE_END]);
737 errpipe[WRITE_END] = -1;
740 spawn_read(event, cmd,
741 outpipe[READ_END], errpipe[READ_END],
744 err = spawn_wait(event, cmd, pid);
748 if (outpipe[READ_END] >= 0)
749 close(outpipe[READ_END]);
750 if (outpipe[WRITE_END] >= 0)
751 close(outpipe[WRITE_END]);
752 if (errpipe[READ_END] >= 0)
753 close(errpipe[READ_END]);
754 if (errpipe[WRITE_END] >= 0)
755 close(errpipe[WRITE_END]);
759 static void rename_netif_kernel_log(struct ifreq ifr)
764 klog = open("/dev/kmsg", O_WRONLY);
768 f = fdopen(klog, "w");
774 fprintf(f, "<30>udevd[%u]: renamed network interface %s to %s\n",
775 getpid(), ifr.ifr_name, ifr.ifr_newname);
779 static int rename_netif(struct udev_event *event)
781 struct udev_device *dev = event->dev;
787 log_debug("changing net interface name from '%s' to '%s'\n",
788 udev_device_get_sysname(dev), event->name);
790 sk = socket(PF_INET, SOCK_DGRAM, 0);
793 log_error("error opening socket: %m\n");
797 memset(&ifr, 0x00, sizeof(struct ifreq));
798 util_strscpy(ifr.ifr_name, IFNAMSIZ, udev_device_get_sysname(dev));
799 util_strscpy(ifr.ifr_newname, IFNAMSIZ, event->name);
800 err = ioctl(sk, SIOCSIFNAME, &ifr);
802 rename_netif_kernel_log(ifr);
806 /* keep trying if the destination interface name already exists */
811 /* free our own name, another process may wait for us */
812 snprintf(ifr.ifr_newname, IFNAMSIZ, "rename%u", udev_device_get_ifindex(dev));
813 err = ioctl(sk, SIOCSIFNAME, &ifr);
819 /* log temporary name */
820 rename_netif_kernel_log(ifr);
822 /* wait a maximum of 90 seconds for our target to become available */
823 util_strscpy(ifr.ifr_name, IFNAMSIZ, ifr.ifr_newname);
824 util_strscpy(ifr.ifr_newname, IFNAMSIZ, event->name);
827 const struct timespec duration = { 0, 1000 * 1000 * 1000 / 20 };
829 nanosleep(&duration, NULL);
831 err = ioctl(sk, SIOCSIFNAME, &ifr);
833 rename_netif_kernel_log(ifr);
843 log_error("error changing net interface name %s to %s: %m\n", ifr.ifr_name, ifr.ifr_newname);
848 int udev_event_execute_rules(struct udev_event *event, struct udev_rules *rules, const sigset_t *sigmask)
850 struct udev_device *dev = event->dev;
853 if (udev_device_get_subsystem(dev) == NULL)
856 if (strcmp(udev_device_get_action(dev), "remove") == 0) {
857 udev_device_read_db(dev, NULL);
858 udev_device_delete_db(dev);
859 udev_device_tag_index(dev, NULL, false);
861 if (major(udev_device_get_devnum(dev)) != 0)
862 udev_watch_end(event->udev, dev);
864 udev_rules_apply_to_event(rules, event, sigmask);
866 if (major(udev_device_get_devnum(dev)) != 0)
867 udev_node_remove(dev);
869 event->dev_db = udev_device_new_from_syspath(event->udev, udev_device_get_syspath(dev));
870 if (event->dev_db != NULL) {
871 udev_device_read_db(event->dev_db, NULL);
872 udev_device_set_info_loaded(event->dev_db);
874 /* disable watch during event processing */
875 if (major(udev_device_get_devnum(dev)) != 0)
876 udev_watch_end(event->udev, event->dev_db);
879 udev_rules_apply_to_event(rules, event, sigmask);
881 /* rename a new network interface, if needed */
882 if (udev_device_get_ifindex(dev) > 0 && strcmp(udev_device_get_action(dev), "add") == 0 &&
883 event->name != NULL && strcmp(event->name, udev_device_get_sysname(dev)) != 0) {
884 char syspath[UTIL_PATH_SIZE];
887 err = rename_netif(event);
889 log_debug("renamed netif to '%s'\n", event->name);
891 /* remember old name */
892 udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev));
894 /* now change the devpath, because the kernel device name has changed */
895 util_strscpy(syspath, sizeof(syspath), udev_device_get_syspath(dev));
896 pos = strrchr(syspath, '/');
899 util_strscpy(pos, sizeof(syspath) - (pos - syspath), event->name);
900 udev_device_set_syspath(event->dev, syspath);
901 udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev));
902 log_debug("changed devpath to '%s'\n", udev_device_get_devpath(dev));
907 if (major(udev_device_get_devnum(dev)) > 0) {
908 /* remove/update possible left-over symlinks from old database entry */
909 if (event->dev_db != NULL)
910 udev_node_update_old_links(dev, event->dev_db);
912 if (!event->mode_set) {
913 if (udev_device_get_devnode_mode(dev) > 0) {
914 /* kernel supplied value */
915 event->mode = udev_device_get_devnode_mode(dev);
916 } else if (event->gid > 0) {
917 /* default 0660 if a group is assigned */
925 udev_node_add(dev, event->mode, event->uid, event->gid);
928 /* preserve old, or get new initialization timestamp */
929 if (event->dev_db != NULL && udev_device_get_usec_initialized(event->dev_db) > 0)
930 udev_device_set_usec_initialized(event->dev, udev_device_get_usec_initialized(event->dev_db));
931 else if (udev_device_get_usec_initialized(event->dev) == 0)
932 udev_device_set_usec_initialized(event->dev, now_usec());
934 /* (re)write database file */
935 udev_device_update_db(dev);
936 udev_device_tag_index(dev, event->dev_db, true);
937 udev_device_set_is_initialized(dev);
939 udev_device_unref(event->dev_db);
940 event->dev_db = NULL;
946 int udev_event_execute_run(struct udev_event *event, const sigset_t *sigmask)
948 struct udev_list_entry *list_entry;
951 udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
952 const char *cmd = udev_list_entry_get_name(list_entry);
954 if (strncmp(cmd, "socket:", strlen("socket:")) == 0) {
955 struct udev_monitor *monitor;
957 monitor = udev_monitor_new_from_socket(event->udev, &cmd[strlen("socket:")]);
960 udev_monitor_send_device(monitor, NULL, event->dev);
961 udev_monitor_unref(monitor);
963 char program[UTIL_PATH_SIZE];
966 if (event->exec_delay > 0) {
967 log_debug("delay execution of '%s'\n", program);
968 sleep(event->exec_delay);
971 udev_event_apply_format(event, cmd, program, sizeof(program));
972 envp = udev_device_get_properties_envp(event->dev);
973 if (udev_event_spawn(event, program, envp, sigmask, NULL, 0) < 0) {
974 if (udev_list_entry_get_num(list_entry))