2 * Copyright (C) 2003-2013 Kay Sievers <kay@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/prctl.h>
30 #include <sys/epoll.h>
32 #include <sys/signalfd.h>
35 #include "rtnl-util.h"
37 struct udev_event *udev_event_new(struct udev_device *dev) {
38 struct udev *udev = udev_device_get_udev(dev);
39 struct udev_event *event;
41 event = new0(struct udev_event, 1);
46 udev_list_init(udev, &event->run_list, false);
47 udev_list_init(udev, &event->seclabel_list, false);
48 event->fd_signal = -1;
49 event->birth_usec = now(CLOCK_MONOTONIC);
53 void udev_event_unref(struct udev_event *event) {
56 sd_rtnl_unref(event->rtnl);
57 udev_list_cleanup(&event->run_list);
58 udev_list_cleanup(&event->seclabel_list);
59 free(event->program_result);
64 size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size) {
65 struct udev_device *dev = event->dev;
85 static const struct subst_map {
90 { .name = "devnode", .fmt = 'N', .type = SUBST_DEVNODE },
91 { .name = "tempnode", .fmt = 'N', .type = SUBST_DEVNODE },
92 { .name = "attr", .fmt = 's', .type = SUBST_ATTR },
93 { .name = "sysfs", .fmt = 's', .type = SUBST_ATTR },
94 { .name = "env", .fmt = 'E', .type = SUBST_ENV },
95 { .name = "kernel", .fmt = 'k', .type = SUBST_KERNEL },
96 { .name = "number", .fmt = 'n', .type = SUBST_KERNEL_NUMBER },
97 { .name = "driver", .fmt = 'd', .type = SUBST_DRIVER },
98 { .name = "devpath", .fmt = 'p', .type = SUBST_DEVPATH },
99 { .name = "id", .fmt = 'b', .type = SUBST_ID },
100 { .name = "major", .fmt = 'M', .type = SUBST_MAJOR },
101 { .name = "minor", .fmt = 'm', .type = SUBST_MINOR },
102 { .name = "result", .fmt = 'c', .type = SUBST_RESULT },
103 { .name = "parent", .fmt = 'P', .type = SUBST_PARENT },
104 { .name = "name", .fmt = 'D', .type = SUBST_NAME },
105 { .name = "links", .fmt = 'L', .type = SUBST_LINKS },
106 { .name = "root", .fmt = 'r', .type = SUBST_ROOT },
107 { .name = "sys", .fmt = 'S', .type = SUBST_SYS },
118 enum subst_type type = SUBST_UNKNOWN;
119 char attrbuf[UTIL_PATH_SIZE];
122 while (from[0] != '\0') {
123 if (from[0] == '$') {
124 /* substitute named variable */
127 if (from[1] == '$') {
132 for (i = 0; i < ELEMENTSOF(map); i++) {
133 if (startswith(&from[1], map[i].name)) {
135 from += strlen(map[i].name)+1;
139 } else if (from[0] == '%') {
140 /* substitute format char */
143 if (from[1] == '%') {
148 for (i = 0; i < ELEMENTSOF(map); i++) {
149 if (from[1] == map[i].fmt) {
168 /* extract possible $format{attr} */
169 if (from[0] == '{') {
173 for (i = 0; from[i] != '}'; i++) {
174 if (from[i] == '\0') {
175 log_error("missing closing brace for format '%s'", src);
179 if (i >= sizeof(attrbuf))
181 memcpy(attrbuf, from, i);
191 l = strpcpy(&s, l, udev_device_get_devpath(dev));
194 l = strpcpy(&s, l, udev_device_get_sysname(dev));
196 case SUBST_KERNEL_NUMBER:
197 if (udev_device_get_sysnum(dev) == NULL)
199 l = strpcpy(&s, l, udev_device_get_sysnum(dev));
202 if (event->dev_parent == NULL)
204 l = strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
209 if (event->dev_parent == NULL)
212 driver = udev_device_get_driver(event->dev_parent);
215 l = strpcpy(&s, l, driver);
219 char num[UTIL_PATH_SIZE];
221 sprintf(num, "%d", major(udev_device_get_devnum(dev)));
222 l = strpcpy(&s, l, num);
226 char num[UTIL_PATH_SIZE];
228 sprintf(num, "%d", minor(udev_device_get_devnum(dev)));
229 l = strpcpy(&s, l, num);
236 if (event->program_result == NULL)
238 /* get part part of the result string */
241 i = strtoul(attr, &rest, 10);
243 char result[UTIL_PATH_SIZE];
244 char tmp[UTIL_PATH_SIZE];
247 strscpy(result, sizeof(result), event->program_result);
250 while (cpos[0] != '\0' && !isspace(cpos[0]))
252 while (isspace(cpos[0]))
258 log_error("requested part of result string not found");
261 strscpy(tmp, sizeof(tmp), cpos);
262 /* %{2+}c copies the whole string from the second part on */
263 if (rest[0] != '+') {
264 cpos = strchr(tmp, ' ');
268 l = strpcpy(&s, l, tmp);
270 l = strpcpy(&s, l, event->program_result);
275 const char *value = NULL;
276 char vbuf[UTIL_NAME_SIZE];
281 log_error("missing file parameter for attr");
285 /* try to read the value specified by "[dmi/id]product_name" */
286 if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0)
289 /* try to read the attribute the device */
291 value = udev_device_get_sysattr_value(event->dev, attr);
293 /* try to read the attribute of the parent device, other matches have selected */
294 if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev)
295 value = udev_device_get_sysattr_value(event->dev_parent, attr);
300 /* strip trailing whitespace, and replace unwanted characters */
302 strscpy(vbuf, sizeof(vbuf), value);
304 while (len > 0 && isspace(vbuf[--len]))
306 count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
308 log_debug("%i character(s) replaced" , count);
309 l = strpcpy(&s, l, vbuf);
313 struct udev_device *dev_parent;
316 dev_parent = udev_device_get_parent(event->dev);
317 if (dev_parent == NULL)
319 devnode = udev_device_get_devnode(dev_parent);
321 l = strpcpy(&s, l, devnode + strlen("/dev/"));
325 if (udev_device_get_devnode(dev) != NULL)
326 l = strpcpy(&s, l, udev_device_get_devnode(dev));
329 if (event->name != NULL)
330 l = strpcpy(&s, l, event->name);
331 else if (udev_device_get_devnode(dev) != NULL)
332 l = strpcpy(&s, l, udev_device_get_devnode(dev) + strlen("/dev/"));
334 l = strpcpy(&s, l, udev_device_get_sysname(dev));
337 struct udev_list_entry *list_entry;
339 list_entry = udev_device_get_devlinks_list_entry(dev);
340 if (list_entry == NULL)
342 l = strpcpy(&s, l, udev_list_entry_get_name(list_entry) + strlen("/dev/"));
343 udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
344 l = strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry) + strlen("/dev/"), NULL);
348 l = strpcpy(&s, l, "/dev");
351 l = strpcpy(&s, l, "/sys");
359 value = udev_device_get_property_value(event->dev, attr);
362 l = strpcpy(&s, l, value);
366 log_error("unknown substitution type=%i", type);
376 static int spawn_exec(struct udev_event *event,
377 const char *cmd, char *const argv[], char **envp, const sigset_t *sigmask,
378 int fd_stdout, int fd_stderr) {
379 _cleanup_close_ int fd = -1;
381 /* discard child output or connect to pipe */
382 fd = open("/dev/null", O_RDWR);
384 dup2(fd, STDIN_FILENO);
386 dup2(fd, STDOUT_FILENO);
388 dup2(fd, STDERR_FILENO);
390 log_error_errno(errno, "open /dev/null failed: %m");
392 /* connect pipes to std{out,err} */
393 if (fd_stdout >= 0) {
394 dup2(fd_stdout, STDOUT_FILENO);
395 safe_close(fd_stdout);
397 if (fd_stderr >= 0) {
398 dup2(fd_stderr, STDERR_FILENO);
399 safe_close(fd_stderr);
402 /* terminate child in case parent goes away */
403 prctl(PR_SET_PDEATHSIG, SIGTERM);
405 /* restore original udev sigmask before exec */
407 sigprocmask(SIG_SETMASK, sigmask, NULL);
409 execve(argv[0], argv, envp);
412 log_error_errno(errno, "failed to execute '%s' '%s': %m", argv[0], cmd);
417 static void spawn_read(struct udev_event *event,
420 int fd_stdout, int fd_stderr,
421 char *result, size_t ressize) {
422 _cleanup_close_ int fd_ep = -1;
423 struct epoll_event ep_outpipe = {
425 .data.ptr = &fd_stdout,
427 struct epoll_event ep_errpipe = {
429 .data.ptr = &fd_stderr,
434 /* read from child if requested */
435 if (fd_stdout < 0 && fd_stderr < 0)
438 fd_ep = epoll_create1(EPOLL_CLOEXEC);
440 log_error_errno(errno, "error creating epoll fd: %m");
444 if (fd_stdout >= 0) {
445 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe);
447 log_error_errno(errno, "fail to add stdout fd to epoll: %m");
452 if (fd_stderr >= 0) {
453 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe);
455 log_error_errno(errno, "fail to add stderr fd to epoll: %m");
460 /* read child output */
461 while (fd_stdout >= 0 || fd_stderr >= 0) {
464 struct epoll_event ev[4];
467 if (timeout_usec > 0) {
470 age_usec = now(CLOCK_MONOTONIC) - event->birth_usec;
471 if (age_usec >= timeout_usec) {
472 log_error("timeout '%s'", cmd);
475 timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
480 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
484 log_error_errno(errno, "failed to poll: %m");
486 } else if (fdcount == 0) {
487 log_error("timeout '%s'", cmd);
491 for (i = 0; i < fdcount; i++) {
492 int *fd = (int *)ev[i].data.ptr;
497 if (ev[i].events & EPOLLIN) {
501 count = read(*fd, buf, sizeof(buf)-1);
506 /* store stdout result */
507 if (result != NULL && *fd == fd_stdout) {
508 if (respos + count < ressize) {
509 memcpy(&result[respos], buf, count);
512 log_error("'%s' ressize %zd too short", cmd, ressize);
516 /* log debug output only if we watch stderr */
517 if (fd_stderr >= 0) {
522 while ((line = strsep(&pos, "\n"))) {
523 if (pos != NULL || line[0] != '\0')
524 log_debug("'%s'(%s) '%s'", cmd, *fd == fd_stdout ? "out" : "err" , line);
527 } else if (ev[i].events & EPOLLHUP) {
528 r = epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL);
530 log_error_errno(errno, "failed to remove fd from epoll: %m");
538 /* return the child's stdout string */
540 result[respos] = '\0';
543 static int spawn_wait(struct udev_event *event,
545 usec_t timeout_warn_usec,
546 const char *cmd, pid_t pid) {
547 struct pollfd pfd[1];
550 pfd[0].events = POLLIN;
551 pfd[0].fd = event->fd_signal;
555 int timeout_warn = 0;
558 if (timeout_usec > 0) {
561 age_usec = now(CLOCK_MONOTONIC) - event->birth_usec;
562 if (age_usec >= timeout_usec)
565 if (timeout_warn_usec > 0)
566 timeout_warn = ((timeout_warn_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
568 timeout = ((timeout_usec - timeout_warn_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
574 fdcount = poll(pfd, 1, timeout_warn);
579 log_error_errno(errno, "failed to poll: %m");
583 log_warning("slow: '%s' [%u]", cmd, pid);
585 fdcount = poll(pfd, 1, timeout);
590 log_error_errno(errno, "failed to poll: %m");
594 log_error("timeout: killing '%s' [%u]", cmd, pid);
599 if (pfd[0].revents & POLLIN) {
600 struct signalfd_siginfo fdsi;
604 size = read(event->fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
605 if (size != sizeof(struct signalfd_siginfo))
608 switch (fdsi.ssi_signo) {
610 event->sigterm = true;
613 if (waitpid(pid, &status, WNOHANG) < 0)
615 if (WIFEXITED(status)) {
616 log_debug("'%s' [%u] exit with return code %i", cmd, pid, WEXITSTATUS(status));
617 if (WEXITSTATUS(status) != 0)
619 } else if (WIFSIGNALED(status)) {
620 log_error("'%s' [%u] terminated by signal %i (%s)", cmd, pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
622 } else if (WIFSTOPPED(status)) {
623 log_error("'%s' [%u] stopped", cmd, pid);
625 } else if (WIFCONTINUED(status)) {
626 log_error("'%s' [%u] continued", cmd, pid);
629 log_error("'%s' [%u] exit with status 0x%04x", cmd, pid, status);
641 int udev_build_argv(struct udev *udev, char *cmd, int *argc, char *argv[]) {
645 if (strchr(cmd, ' ') == NULL) {
651 while (pos != NULL && pos[0] != '\0') {
652 if (pos[0] == '\'') {
653 /* do not separate quotes */
655 argv[i] = strsep(&pos, "\'");
657 while (pos[0] == ' ')
660 argv[i] = strsep(&pos, " ");
662 while (pos[0] == ' ')
674 int udev_event_spawn(struct udev_event *event,
676 usec_t timeout_warn_usec,
677 const char *cmd, char **envp, const sigset_t *sigmask,
678 char *result, size_t ressize) {
679 int outpipe[2] = {-1, -1};
680 int errpipe[2] = {-1, -1};
682 char arg[UTIL_PATH_SIZE];
684 char program[UTIL_PATH_SIZE];
687 strscpy(arg, sizeof(arg), cmd);
688 udev_build_argv(event->udev, arg, NULL, argv);
690 /* pipes from child to parent */
691 if (result != NULL || log_get_max_level() >= LOG_INFO) {
692 if (pipe2(outpipe, O_NONBLOCK) != 0) {
694 log_error_errno(errno, "pipe failed: %m");
698 if (log_get_max_level() >= LOG_INFO) {
699 if (pipe2(errpipe, O_NONBLOCK) != 0) {
701 log_error_errno(errno, "pipe failed: %m");
706 /* allow programs in /usr/lib/udev/ to be called without the path */
707 if (argv[0][0] != '/') {
708 strscpyl(program, sizeof(program), UDEVLIBEXECDIR "/", argv[0], NULL);
715 /* child closes parent's ends of pipes */
716 if (outpipe[READ_END] >= 0) {
717 close(outpipe[READ_END]);
718 outpipe[READ_END] = -1;
720 if (errpipe[READ_END] >= 0) {
721 close(errpipe[READ_END]);
722 errpipe[READ_END] = -1;
725 log_debug("starting '%s'", cmd);
727 spawn_exec(event, cmd, argv, envp, sigmask,
728 outpipe[WRITE_END], errpipe[WRITE_END]);
732 log_error_errno(errno, "fork of '%s' failed: %m", cmd);
736 /* parent closed child's ends of pipes */
737 if (outpipe[WRITE_END] >= 0) {
738 close(outpipe[WRITE_END]);
739 outpipe[WRITE_END] = -1;
741 if (errpipe[WRITE_END] >= 0) {
742 close(errpipe[WRITE_END]);
743 errpipe[WRITE_END] = -1;
749 outpipe[READ_END], errpipe[READ_END],
752 err = spawn_wait(event, timeout_usec, timeout_warn_usec, cmd, pid);
756 if (outpipe[READ_END] >= 0)
757 close(outpipe[READ_END]);
758 if (outpipe[WRITE_END] >= 0)
759 close(outpipe[WRITE_END]);
760 if (errpipe[READ_END] >= 0)
761 close(errpipe[READ_END]);
762 if (errpipe[WRITE_END] >= 0)
763 close(errpipe[WRITE_END]);
767 static int rename_netif(struct udev_event *event) {
768 struct udev_device *dev = event->dev;
773 oldname = udev_device_get_sysname(dev);
775 strscpy(name, IFNAMSIZ, event->name);
777 r = rtnl_set_link_name(&event->rtnl, udev_device_get_ifindex(dev), name);
779 return log_error_errno(r, "Error changing net interface name '%s' to '%s': %m", oldname, name);
781 log_debug("renamed network interface '%s' to '%s'", oldname, name);
786 void udev_event_execute_rules(struct udev_event *event,
787 usec_t timeout_usec, usec_t timeout_warn_usec,
788 struct udev_list *properties_list,
789 struct udev_rules *rules,
790 const sigset_t *sigmask) {
791 struct udev_device *dev = event->dev;
793 if (udev_device_get_subsystem(dev) == NULL)
796 if (streq(udev_device_get_action(dev), "remove")) {
797 udev_device_read_db(dev, NULL);
798 udev_device_delete_db(dev);
799 udev_device_tag_index(dev, NULL, false);
801 if (major(udev_device_get_devnum(dev)) != 0)
802 udev_watch_end(event->udev, dev);
804 udev_rules_apply_to_event(rules, event,
805 timeout_usec, timeout_warn_usec,
809 if (major(udev_device_get_devnum(dev)) != 0)
810 udev_node_remove(dev);
812 event->dev_db = udev_device_new(event->udev);
813 if (event->dev_db != NULL) {
814 udev_device_set_syspath(event->dev_db, udev_device_get_syspath(dev));
815 udev_device_set_subsystem(event->dev_db, udev_device_get_subsystem(dev));
816 udev_device_set_devnum(event->dev_db, udev_device_get_devnum(dev));
817 udev_device_read_db(event->dev_db, NULL);
818 udev_device_set_info_loaded(event->dev_db);
820 /* disable watch during event processing */
821 if (major(udev_device_get_devnum(dev)) != 0)
822 udev_watch_end(event->udev, event->dev_db);
825 if (major(udev_device_get_devnum(dev)) == 0 &&
826 streq(udev_device_get_action(dev), "move")) {
827 struct udev_list_entry *entry;
829 for ((entry = udev_device_get_properties_list_entry(event->dev_db)); entry; entry = udev_list_entry_get_next(entry)) {
830 const char *key, *value;
831 struct udev_list_entry *property;
833 key = udev_list_entry_get_name(entry);
834 value = udev_list_entry_get_value(entry);
836 property = udev_device_add_property(event->dev, key, value);
837 udev_list_entry_set_num(property, true);
841 udev_rules_apply_to_event(rules, event,
842 timeout_usec, timeout_warn_usec,
846 /* rename a new network interface, if needed */
847 if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
848 event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
849 char syspath[UTIL_PATH_SIZE];
853 r = rename_netif(event);
855 /* remember old name */
856 udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev));
858 /* now change the devpath, because the kernel device name has changed */
859 strscpy(syspath, sizeof(syspath), udev_device_get_syspath(dev));
860 pos = strrchr(syspath, '/');
863 strscpy(pos, sizeof(syspath) - (pos - syspath), event->name);
864 udev_device_set_syspath(event->dev, syspath);
865 udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev));
866 log_debug("changed devpath to '%s'", udev_device_get_devpath(dev));
871 if (major(udev_device_get_devnum(dev)) > 0) {
874 /* remove/update possible left-over symlinks from old database entry */
875 if (event->dev_db != NULL)
876 udev_node_update_old_links(dev, event->dev_db);
878 if (!event->owner_set)
879 event->uid = udev_device_get_devnode_uid(dev);
881 if (!event->group_set)
882 event->gid = udev_device_get_devnode_gid(dev);
884 if (!event->mode_set) {
885 if (udev_device_get_devnode_mode(dev) > 0) {
886 /* kernel supplied value */
887 event->mode = udev_device_get_devnode_mode(dev);
888 } else if (event->gid > 0) {
889 /* default 0660 if a group is assigned */
897 apply = streq(udev_device_get_action(dev), "add") || event->owner_set || event->group_set || event->mode_set;
898 udev_node_add(dev, apply, event->mode, event->uid, event->gid, &event->seclabel_list);
901 /* preserve old, or get new initialization timestamp */
902 if (event->dev_db != NULL && udev_device_get_usec_initialized(event->dev_db) > 0)
903 udev_device_set_usec_initialized(event->dev, udev_device_get_usec_initialized(event->dev_db));
904 else if (udev_device_get_usec_initialized(event->dev) == 0)
905 udev_device_set_usec_initialized(event->dev, now(CLOCK_MONOTONIC));
907 /* (re)write database file */
908 udev_device_update_db(dev);
909 udev_device_tag_index(dev, event->dev_db, true);
910 udev_device_set_is_initialized(dev);
912 udev_device_unref(event->dev_db);
913 event->dev_db = NULL;
917 void udev_event_execute_run(struct udev_event *event, usec_t timeout_usec, usec_t timeout_warn_usec, const sigset_t *sigmask) {
918 struct udev_list_entry *list_entry;
920 udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
921 const char *cmd = udev_list_entry_get_name(list_entry);
922 enum udev_builtin_cmd builtin_cmd = udev_list_entry_get_num(list_entry);
924 if (builtin_cmd < UDEV_BUILTIN_MAX) {
925 char command[UTIL_PATH_SIZE];
927 udev_event_apply_format(event, cmd, command, sizeof(command));
928 udev_builtin_run(event->dev, builtin_cmd, command, false);
930 char program[UTIL_PATH_SIZE];
933 if (event->exec_delay > 0) {
934 log_debug("delay execution of '%s'", program);
935 sleep(event->exec_delay);
938 udev_event_apply_format(event, cmd, program, sizeof(program));
939 envp = udev_device_get_properties_envp(event->dev);
940 udev_event_spawn(event, timeout_usec, timeout_warn_usec, program, envp, sigmask, NULL, 0);