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)
39 struct udev *udev = udev_device_get_udev(dev);
40 struct udev_event *event;
42 event = new0(struct udev_event, 1);
47 udev_list_init(udev, &event->run_list, false);
48 udev_list_init(udev, &event->seclabel_list, false);
49 event->fd_signal = -1;
50 event->birth_usec = now(CLOCK_MONOTONIC);
54 void udev_event_unref(struct udev_event *event)
58 udev_list_cleanup(&event->run_list);
59 udev_list_cleanup(&event->seclabel_list);
60 free(event->program_result);
65 size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size)
67 struct udev_device *dev = event->dev;
87 static const struct subst_map {
92 { .name = "devnode", .fmt = 'N', .type = SUBST_DEVNODE },
93 { .name = "tempnode", .fmt = 'N', .type = SUBST_DEVNODE },
94 { .name = "attr", .fmt = 's', .type = SUBST_ATTR },
95 { .name = "sysfs", .fmt = 's', .type = SUBST_ATTR },
96 { .name = "env", .fmt = 'E', .type = SUBST_ENV },
97 { .name = "kernel", .fmt = 'k', .type = SUBST_KERNEL },
98 { .name = "number", .fmt = 'n', .type = SUBST_KERNEL_NUMBER },
99 { .name = "driver", .fmt = 'd', .type = SUBST_DRIVER },
100 { .name = "devpath", .fmt = 'p', .type = SUBST_DEVPATH },
101 { .name = "id", .fmt = 'b', .type = SUBST_ID },
102 { .name = "major", .fmt = 'M', .type = SUBST_MAJOR },
103 { .name = "minor", .fmt = 'm', .type = SUBST_MINOR },
104 { .name = "result", .fmt = 'c', .type = SUBST_RESULT },
105 { .name = "parent", .fmt = 'P', .type = SUBST_PARENT },
106 { .name = "name", .fmt = 'D', .type = SUBST_NAME },
107 { .name = "links", .fmt = 'L', .type = SUBST_LINKS },
108 { .name = "root", .fmt = 'r', .type = SUBST_ROOT },
109 { .name = "sys", .fmt = 'S', .type = SUBST_SYS },
120 enum subst_type type = SUBST_UNKNOWN;
121 char attrbuf[UTIL_PATH_SIZE];
124 while (from[0] != '\0') {
125 if (from[0] == '$') {
126 /* substitute named variable */
129 if (from[1] == '$') {
134 for (i = 0; i < ELEMENTSOF(map); i++) {
135 if (startswith(&from[1], map[i].name)) {
137 from += strlen(map[i].name)+1;
141 } else if (from[0] == '%') {
142 /* substitute format char */
145 if (from[1] == '%') {
150 for (i = 0; i < ELEMENTSOF(map); i++) {
151 if (from[1] == map[i].fmt) {
170 /* extract possible $format{attr} */
171 if (from[0] == '{') {
175 for (i = 0; from[i] != '}'; i++) {
176 if (from[i] == '\0') {
177 log_error("missing closing brace for format '%s'", src);
181 if (i >= sizeof(attrbuf))
183 memcpy(attrbuf, from, i);
193 l = strpcpy(&s, l, udev_device_get_devpath(dev));
196 l = strpcpy(&s, l, udev_device_get_sysname(dev));
198 case SUBST_KERNEL_NUMBER:
199 if (udev_device_get_sysnum(dev) == NULL)
201 l = strpcpy(&s, l, udev_device_get_sysnum(dev));
204 if (event->dev_parent == NULL)
206 l = strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
211 if (event->dev_parent == NULL)
214 driver = udev_device_get_driver(event->dev_parent);
217 l = strpcpy(&s, l, driver);
221 char num[UTIL_PATH_SIZE];
223 sprintf(num, "%d", major(udev_device_get_devnum(dev)));
224 l = strpcpy(&s, l, num);
228 char num[UTIL_PATH_SIZE];
230 sprintf(num, "%d", minor(udev_device_get_devnum(dev)));
231 l = strpcpy(&s, l, num);
238 if (event->program_result == NULL)
240 /* get part part of the result string */
243 i = strtoul(attr, &rest, 10);
245 char result[UTIL_PATH_SIZE];
246 char tmp[UTIL_PATH_SIZE];
249 strscpy(result, sizeof(result), event->program_result);
252 while (cpos[0] != '\0' && !isspace(cpos[0]))
254 while (isspace(cpos[0]))
260 log_error("requested part of result string not found");
263 strscpy(tmp, sizeof(tmp), cpos);
264 /* %{2+}c copies the whole string from the second part on */
265 if (rest[0] != '+') {
266 cpos = strchr(tmp, ' ');
270 l = strpcpy(&s, l, tmp);
272 l = strpcpy(&s, l, event->program_result);
277 const char *value = NULL;
278 char vbuf[UTIL_NAME_SIZE];
283 log_error("missing file parameter for attr");
287 /* try to read the value specified by "[dmi/id]product_name" */
288 if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0)
291 /* try to read the attribute the device */
293 value = udev_device_get_sysattr_value(event->dev, attr);
295 /* try to read the attribute of the parent device, other matches have selected */
296 if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev)
297 value = udev_device_get_sysattr_value(event->dev_parent, attr);
302 /* strip trailing whitespace, and replace unwanted characters */
304 strscpy(vbuf, sizeof(vbuf), value);
306 while (len > 0 && isspace(vbuf[--len]))
308 count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
310 log_debug("%i character(s) replaced" , count);
311 l = strpcpy(&s, l, vbuf);
315 struct udev_device *dev_parent;
318 dev_parent = udev_device_get_parent(event->dev);
319 if (dev_parent == NULL)
321 devnode = udev_device_get_devnode(dev_parent);
323 l = strpcpy(&s, l, devnode + strlen("/dev/"));
327 if (udev_device_get_devnode(dev) != NULL)
328 l = strpcpy(&s, l, udev_device_get_devnode(dev));
331 if (event->name != NULL)
332 l = strpcpy(&s, l, event->name);
333 else if (udev_device_get_devnode(dev) != NULL)
334 l = strpcpy(&s, l, udev_device_get_devnode(dev) + strlen("/dev/"));
336 l = strpcpy(&s, l, udev_device_get_sysname(dev));
339 struct udev_list_entry *list_entry;
341 list_entry = udev_device_get_devlinks_list_entry(dev);
342 if (list_entry == NULL)
344 l = strpcpy(&s, l, udev_list_entry_get_name(list_entry) + strlen("/dev/"));
345 udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
346 l = strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry) + strlen("/dev/"), NULL);
350 l = strpcpy(&s, l, "/dev");
353 l = strpcpy(&s, l, "/sys");
361 value = udev_device_get_property_value(event->dev, attr);
364 l = strpcpy(&s, l, value);
368 log_error("unknown substitution type=%i", type);
378 static int spawn_exec(struct udev_event *event,
379 const char *cmd, char *const argv[], char **envp, const sigset_t *sigmask,
380 int fd_stdout, int fd_stderr)
385 /* discard child output or connect to pipe */
386 fd = open("/dev/null", O_RDWR);
388 dup2(fd, STDIN_FILENO);
390 dup2(fd, STDOUT_FILENO);
392 dup2(fd, STDERR_FILENO);
395 log_error("open /dev/null failed: %m");
398 /* connect pipes to std{out,err} */
399 if (fd_stdout >= 0) {
400 dup2(fd_stdout, STDOUT_FILENO);
403 if (fd_stderr >= 0) {
404 dup2(fd_stderr, STDERR_FILENO);
408 /* terminate child in case parent goes away */
409 prctl(PR_SET_PDEATHSIG, SIGTERM);
411 /* restore original udev sigmask before exec */
413 sigprocmask(SIG_SETMASK, sigmask, NULL);
415 execve(argv[0], argv, envp);
419 log_error("failed to execute '%s' '%s': %m", argv[0], cmd);
423 static void spawn_read(struct udev_event *event,
426 int fd_stdout, int fd_stderr,
427 char *result, size_t ressize)
431 struct epoll_event ep_outpipe, ep_errpipe;
433 /* read from child if requested */
434 if (fd_stdout < 0 && fd_stderr < 0)
437 fd_ep = epoll_create1(EPOLL_CLOEXEC);
439 log_error("error creating epoll fd: %m");
443 if (fd_stdout >= 0) {
444 memzero(&ep_outpipe, sizeof(struct epoll_event));
445 ep_outpipe.events = EPOLLIN;
446 ep_outpipe.data.ptr = &fd_stdout;
447 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe) < 0) {
448 log_error("fail to add fd to epoll: %m");
453 if (fd_stderr >= 0) {
454 memzero(&ep_errpipe, sizeof(struct epoll_event));
455 ep_errpipe.events = EPOLLIN;
456 ep_errpipe.data.ptr = &fd_stderr;
457 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe) < 0) {
458 log_error("fail to add fd to epoll: %m");
463 /* read child output */
464 while (fd_stdout >= 0 || fd_stderr >= 0) {
467 struct epoll_event ev[4];
470 if (timeout_usec > 0) {
473 age_usec = now(CLOCK_MONOTONIC) - event->birth_usec;
474 if (age_usec >= timeout_usec) {
475 log_error("timeout '%s'", cmd);
478 timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
483 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
487 log_error("failed to poll: %m");
491 log_error("timeout '%s'", cmd);
495 for (i = 0; i < fdcount; i++) {
496 int *fd = (int *)ev[i].data.ptr;
498 if (ev[i].events & EPOLLIN) {
502 count = read(*fd, buf, sizeof(buf)-1);
507 /* store stdout result */
508 if (result != NULL && *fd == fd_stdout) {
509 if (respos + count < ressize) {
510 memcpy(&result[respos], buf, count);
513 log_error("'%s' ressize %zd too short", cmd, ressize);
517 /* log debug output only if we watch stderr */
518 if (fd_stderr >= 0) {
523 while ((line = strsep(&pos, "\n"))) {
524 if (pos != NULL || line[0] != '\0')
525 log_debug("'%s'(%s) '%s'", cmd, *fd == fd_stdout ? "out" : "err" , line);
528 } else if (ev[i].events & EPOLLHUP) {
529 if (epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL) < 0) {
530 log_error("failed to remove fd from epoll: %m");
538 /* return the child's stdout string */
540 result[respos] = '\0';
546 static int spawn_wait(struct udev_event *event,
548 const char *cmd, pid_t pid) {
549 struct pollfd pfd[1];
552 pfd[0].events = POLLIN;
553 pfd[0].fd = event->fd_signal;
559 if (timeout_usec > 0) {
562 age_usec = now(CLOCK_MONOTONIC) - event->birth_usec;
563 if (age_usec >= timeout_usec)
566 timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
571 fdcount = poll(pfd, 1, timeout);
576 log_error("failed to poll: %m");
580 log_error("timeout: killing '%s' [%u]", cmd, pid);
584 if (pfd[0].revents & POLLIN) {
585 struct signalfd_siginfo fdsi;
589 size = read(event->fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
590 if (size != sizeof(struct signalfd_siginfo))
593 switch (fdsi.ssi_signo) {
595 event->sigterm = true;
598 if (waitpid(pid, &status, WNOHANG) < 0)
600 if (WIFEXITED(status)) {
601 log_debug("'%s' [%u] exit with return code %i", cmd, pid, WEXITSTATUS(status));
602 if (WEXITSTATUS(status) != 0)
604 } else if (WIFSIGNALED(status)) {
605 log_error("'%s' [%u] terminated by signal %i (%s)", cmd, pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
607 } else if (WIFSTOPPED(status)) {
608 log_error("'%s' [%u] stopped", cmd, pid);
610 } else if (WIFCONTINUED(status)) {
611 log_error("'%s' [%u] continued", cmd, pid);
614 log_error("'%s' [%u] exit with status 0x%04x", cmd, pid, status);
626 int udev_build_argv(struct udev *udev, char *cmd, int *argc, char *argv[])
631 if (strchr(cmd, ' ') == NULL) {
637 while (pos != NULL && pos[0] != '\0') {
638 if (pos[0] == '\'') {
639 /* do not separate quotes */
641 argv[i] = strsep(&pos, "\'");
643 while (pos[0] == ' ')
646 argv[i] = strsep(&pos, " ");
648 while (pos[0] == ' ')
660 int udev_event_spawn(struct udev_event *event,
662 const char *cmd, char **envp, const sigset_t *sigmask,
663 char *result, size_t ressize) {
664 struct udev *udev = event->udev;
665 int outpipe[2] = {-1, -1};
666 int errpipe[2] = {-1, -1};
668 char arg[UTIL_PATH_SIZE];
670 char program[UTIL_PATH_SIZE];
673 strscpy(arg, sizeof(arg), cmd);
674 udev_build_argv(event->udev, arg, NULL, argv);
676 /* pipes from child to parent */
677 if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) {
678 if (pipe2(outpipe, O_NONBLOCK) != 0) {
680 log_error("pipe failed: %m");
684 if (udev_get_log_priority(udev) >= LOG_INFO) {
685 if (pipe2(errpipe, O_NONBLOCK) != 0) {
687 log_error("pipe failed: %m");
692 /* allow programs in /usr/lib/udev/ to be called without the path */
693 if (argv[0][0] != '/') {
694 strscpyl(program, sizeof(program), UDEVLIBEXECDIR "/", argv[0], NULL);
701 /* child closes parent's ends of pipes */
702 if (outpipe[READ_END] >= 0) {
703 close(outpipe[READ_END]);
704 outpipe[READ_END] = -1;
706 if (errpipe[READ_END] >= 0) {
707 close(errpipe[READ_END]);
708 errpipe[READ_END] = -1;
711 log_debug("starting '%s'", cmd);
713 spawn_exec(event, cmd, argv, envp, sigmask,
714 outpipe[WRITE_END], errpipe[WRITE_END]);
718 log_error("fork of '%s' failed: %m", cmd);
722 /* parent closed child's ends of pipes */
723 if (outpipe[WRITE_END] >= 0) {
724 close(outpipe[WRITE_END]);
725 outpipe[WRITE_END] = -1;
727 if (errpipe[WRITE_END] >= 0) {
728 close(errpipe[WRITE_END]);
729 errpipe[WRITE_END] = -1;
735 outpipe[READ_END], errpipe[READ_END],
738 err = spawn_wait(event, timeout_usec, cmd, pid);
742 if (outpipe[READ_END] >= 0)
743 close(outpipe[READ_END]);
744 if (outpipe[WRITE_END] >= 0)
745 close(outpipe[WRITE_END]);
746 if (errpipe[READ_END] >= 0)
747 close(errpipe[READ_END]);
748 if (errpipe[WRITE_END] >= 0)
749 close(errpipe[WRITE_END]);
753 static int rename_netif(struct udev_event *event)
755 struct udev_device *dev = event->dev;
756 _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
761 oldname = udev_device_get_sysname(dev);
763 log_debug("changing net interface name from '%s' to '%s'",
764 oldname, event->name);
766 strscpy(name, IFNAMSIZ, event->name);
768 r = sd_rtnl_open(&rtnl, 0);
772 r = rtnl_set_link_name(rtnl, udev_device_get_ifindex(dev), name);
774 log_error("error changing net interface name %s to %s: %s",
775 oldname, name, strerror(-r));
777 print_kmsg("renamed network interface %s to %s\n", oldname, name);
782 void udev_event_execute_rules(struct udev_event *event,
784 struct udev_rules *rules, const sigset_t *sigmask) {
785 struct udev_device *dev = event->dev;
787 if (udev_device_get_subsystem(dev) == NULL)
790 if (streq(udev_device_get_action(dev), "remove")) {
791 udev_device_read_db(dev, NULL);
792 udev_device_delete_db(dev);
793 udev_device_tag_index(dev, NULL, false);
795 if (major(udev_device_get_devnum(dev)) != 0)
796 udev_watch_end(event->udev, dev);
798 udev_rules_apply_to_event(rules, event, timeout_usec, sigmask);
800 if (major(udev_device_get_devnum(dev)) != 0)
801 udev_node_remove(dev);
803 event->dev_db = udev_device_new(event->udev);
804 if (event->dev_db != NULL) {
805 udev_device_set_syspath(event->dev_db, udev_device_get_syspath(dev));
806 udev_device_set_subsystem(event->dev_db, udev_device_get_subsystem(dev));
807 udev_device_read_db(event->dev_db, NULL);
808 udev_device_set_info_loaded(event->dev_db);
810 /* disable watch during event processing */
811 if (major(udev_device_get_devnum(dev)) != 0)
812 udev_watch_end(event->udev, event->dev_db);
815 udev_rules_apply_to_event(rules, event, timeout_usec, sigmask);
817 /* rename a new network interface, if needed */
818 if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
819 event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
820 char syspath[UTIL_PATH_SIZE];
824 r = rename_netif(event);
826 log_debug("renamed netif to '%s'", event->name);
828 /* remember old name */
829 udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev));
831 /* now change the devpath, because the kernel device name has changed */
832 strscpy(syspath, sizeof(syspath), udev_device_get_syspath(dev));
833 pos = strrchr(syspath, '/');
836 strscpy(pos, sizeof(syspath) - (pos - syspath), event->name);
837 udev_device_set_syspath(event->dev, syspath);
838 udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev));
839 log_debug("changed devpath to '%s'", udev_device_get_devpath(dev));
844 if (major(udev_device_get_devnum(dev)) > 0) {
847 /* remove/update possible left-over symlinks from old database entry */
848 if (event->dev_db != NULL)
849 udev_node_update_old_links(dev, event->dev_db);
851 if (!event->owner_set)
852 event->uid = udev_device_get_devnode_uid(dev);
854 if (!event->group_set)
855 event->gid = udev_device_get_devnode_gid(dev);
857 if (!event->mode_set) {
858 if (udev_device_get_devnode_mode(dev) > 0) {
859 /* kernel supplied value */
860 event->mode = udev_device_get_devnode_mode(dev);
861 } else if (event->gid > 0) {
862 /* default 0660 if a group is assigned */
870 apply = streq(udev_device_get_action(dev), "add") || event->owner_set || event->group_set || event->mode_set;
871 udev_node_add(dev, apply, event->mode, event->uid, event->gid, &event->seclabel_list);
874 /* preserve old, or get new initialization timestamp */
875 if (event->dev_db != NULL && udev_device_get_usec_initialized(event->dev_db) > 0)
876 udev_device_set_usec_initialized(event->dev, udev_device_get_usec_initialized(event->dev_db));
877 else if (udev_device_get_usec_initialized(event->dev) == 0)
878 udev_device_set_usec_initialized(event->dev, now(CLOCK_MONOTONIC));
880 /* (re)write database file */
881 udev_device_update_db(dev);
882 udev_device_tag_index(dev, event->dev_db, true);
883 udev_device_set_is_initialized(dev);
885 udev_device_unref(event->dev_db);
886 event->dev_db = NULL;
890 void udev_event_execute_run(struct udev_event *event, usec_t timeout_usec, const sigset_t *sigmask) {
891 struct udev_list_entry *list_entry;
893 udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
894 const char *cmd = udev_list_entry_get_name(list_entry);
895 enum udev_builtin_cmd builtin_cmd = udev_list_entry_get_num(list_entry);
897 if (builtin_cmd < UDEV_BUILTIN_MAX) {
898 char command[UTIL_PATH_SIZE];
900 udev_event_apply_format(event, cmd, command, sizeof(command));
901 udev_builtin_run(event->dev, builtin_cmd, command, false);
903 char program[UTIL_PATH_SIZE];
906 if (event->exec_delay > 0) {
907 log_debug("delay execution of '%s'", program);
908 sleep(event->exec_delay);
911 udev_event_apply_format(event, cmd, program, sizeof(program));
912 envp = udev_device_get_properties_envp(event->dev);
913 udev_event_spawn(event, timeout_usec, program, envp, sigmask, NULL, 0);