2 * Copyright (C) 2004-2008 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/types.h>
31 #include "udev-rules.h"
33 #define TMP_FILE_EXT ".udev-tmp"
35 /* reverse mapping from the device file name to the devpath */
36 static int name_index(struct udev *udev, const char *devpath, const char *name, int add, int test)
38 char device[UTIL_PATH_SIZE];
39 char filename[UTIL_PATH_SIZE * 2];
40 size_t devlen = strlen(udev_get_dev_path(udev))+1;
44 /* directory with device name */
45 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
46 start = util_strlcat(filename, "/.udev/names/", sizeof(filename));
47 util_strlcat(filename, &name[devlen], sizeof(filename));
48 util_path_encode(&filename[start], sizeof(filename) - start);
49 /* entry with the devpath */
50 util_strlcpy(device, devpath, sizeof(device));
51 util_path_encode(device, sizeof(device));
52 util_strlcat(filename, "/", sizeof(filename));
53 util_strlcat(filename, device, sizeof(filename));
56 info(udev, "creating index: '%s'\n", filename);
57 create_path(udev, filename);
58 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
62 info(udev, "removing index: '%s'\n", filename);
64 delete_path(udev, filename);
69 int udev_node_mknod(struct udev_device *dev, const char *file, dev_t devnum, mode_t mode, uid_t uid, gid_t gid)
71 struct udev *udev = udev_device_get_udev(dev);
72 char file_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)];
77 if (major(devnum) == 0)
78 devnum = udev_device_get_devnum(dev);
80 if (strcmp(udev_device_get_subsystem(dev), "block") == 0)
86 file = udev_device_get_devnode(dev);
88 if (lstat(file, &stats) == 0) {
89 if (((stats.st_mode & S_IFMT) == (mode & S_IFMT)) && (stats.st_rdev == devnum)) {
90 info(udev, "preserve file '%s', because it has correct dev_t\n", file);
92 udev_selinux_lsetfilecon(udev, file, mode);
94 info(udev, "atomically replace existing file '%s'\n", file);
95 util_strlcpy(file_tmp, file, sizeof(file_tmp));
96 util_strlcat(file_tmp, TMP_FILE_EXT, sizeof(file_tmp));
98 udev_selinux_setfscreatecon(udev, file_tmp, mode);
99 err = mknod(file_tmp, mode, devnum);
100 udev_selinux_resetfscreatecon(udev);
102 err(udev, "mknod(%s, %#o, %u, %u) failed: %m\n",
103 file_tmp, mode, major(devnum), minor(devnum));
106 err = rename(file_tmp, file);
108 err(udev, "rename(%s, %s) failed: %m\n", file_tmp, file);
113 info(udev, "mknod(%s, %#o, (%u,%u))\n", file, mode, major(devnum), minor(devnum));
114 udev_selinux_setfscreatecon(udev, file, mode);
115 err = mknod(file, mode, devnum);
116 udev_selinux_resetfscreatecon(udev);
118 err(udev, "mknod(%s, %#o, (%u,%u) failed: %m\n", file, mode, major(devnum), minor(devnum));
123 if (!preserve || stats.st_mode != mode) {
124 info(udev, "chmod(%s, %#o)\n", file, mode);
125 err = chmod(file, mode);
127 err(udev, "chmod(%s, %#o) failed: %m\n", file, mode);
132 if (!preserve || stats.st_uid != uid || stats.st_gid != gid) {
133 info(udev, "chown(%s, %u, %u)\n", file, uid, gid);
134 err = chown(file, uid, gid);
136 err(udev, "chown(%s, %u, %u) failed: %m\n", file, uid, gid);
144 static int node_symlink(struct udev *udev, const char *node, const char *slink)
147 char target[UTIL_PATH_SIZE] = "";
148 char slink_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)];
154 /* use relative link */
155 while (node[i] && (node[i] == slink[i])) {
160 while (slink[i] != '\0') {
162 util_strlcat(target, "../", sizeof(target));
165 util_strlcat(target, &node[tail], sizeof(target));
167 /* preserve link with correct target, do not replace node of other device */
168 if (lstat(slink, &stats) == 0) {
169 if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
172 info(udev, "found existing node instead of symlink '%s'\n", slink);
173 if (lstat(node, &stats2) == 0) {
174 if ((stats.st_mode & S_IFMT) == (stats2.st_mode & S_IFMT) &&
175 stats.st_rdev == stats2.st_rdev) {
176 info(udev, "replace device node '%s' with symlink to our node '%s'\n",
179 err(udev, "device node '%s' already exists, "
180 "link to '%s' will not overwrite it\n",
185 } else if (S_ISLNK(stats.st_mode)) {
186 char buf[UTIL_PATH_SIZE];
188 info(udev, "found existing symlink '%s'\n", slink);
189 len = readlink(slink, buf, sizeof(buf));
192 if (strcmp(target, buf) == 0) {
193 info(udev, "preserve already existing symlink '%s' to '%s'\n",
195 udev_selinux_lsetfilecon(udev, slink, S_IFLNK);
201 info(udev, "creating symlink '%s' to '%s'\n", slink, target);
202 udev_selinux_setfscreatecon(udev, slink, S_IFLNK);
203 err = symlink(target, slink);
204 udev_selinux_resetfscreatecon(udev);
209 info(udev, "atomically replace '%s'\n", slink);
210 util_strlcpy(slink_tmp, slink, sizeof(slink_tmp));
211 util_strlcat(slink_tmp, TMP_FILE_EXT, sizeof(slink_tmp));
213 udev_selinux_setfscreatecon(udev, slink, S_IFLNK);
214 err = symlink(target, slink_tmp);
215 udev_selinux_resetfscreatecon(udev);
217 err(udev, "symlink(%s, %s) failed: %m\n", target, slink_tmp);
220 err = rename(slink_tmp, slink);
222 err(udev, "rename(%s, %s) failed: %m\n", slink_tmp, slink);
230 static int get_devices_by_name(struct udev *udev, const char *name, struct list_head *name_list)
232 char dirname[PATH_MAX];
233 size_t devlen = strlen(udev_get_dev_path(udev))+1;
238 util_strlcpy(dirname, udev_get_dev_path(udev), sizeof(dirname));
239 start = util_strlcat(dirname, "/.udev/names/", sizeof(dirname));
240 util_strlcat(dirname, &name[devlen], sizeof(dirname));
241 util_path_encode(&dirname[start], sizeof(dirname) - start);
243 dir = opendir(dirname);
245 info(udev, "no index directory '%s': %m\n", dirname);
250 info(udev, "found index directory '%s'\n", dirname);
253 char device[UTIL_PATH_SIZE];
256 if (ent == NULL || ent->d_name[0] == '\0')
258 if (ent->d_name[0] == '.')
261 util_strlcpy(device, udev_get_sys_path(udev), sizeof(device));
262 util_strlcat(device, ent->d_name, sizeof(device));
263 util_path_decode(device);
264 name_list_add(udev, name_list, device, 0);
272 static int update_link(struct udev_device *dev, const char *slink, int test)
274 struct udev *udev = udev_device_get_udev(dev);
275 LIST_HEAD(name_list);
276 struct name_entry *device;
277 char target[UTIL_PATH_SIZE] = "";
282 info(udev, "update symlink '%s' of '%s'\n", slink, udev_device_get_syspath(dev));
284 count = get_devices_by_name(udev, slink, &name_list);
285 info(udev, "found %i devices with name '%s'\n", count, slink);
287 /* if we don't have a reference, delete it */
289 info(udev, "no reference left, remove '%s'\n", slink);
292 delete_path(udev, slink);
297 /* find the device with the highest priority */
298 list_for_each_entry(device, &name_list, node) {
299 struct udev_device *dev_db;
302 info(udev, "found '%s' for '%s'\n", device->name, slink);
304 /* did we find ourself? we win, if we have the same priority */
305 if (strcmp(udev_device_get_syspath(dev), device->name) == 0) {
306 info(udev, "compare (our own) priority of '%s' %i >= %i\n",
307 udev_device_get_devpath(dev), udev_device_get_devlink_priority(dev), priority);
308 if (strcmp(udev_device_get_devnode(dev), slink) == 0) {
309 info(udev, "'%s' is our device node, database inconsistent, skip link update\n",
310 udev_device_get_devnode(dev));
311 } else if (target[0] == '\0' || udev_device_get_devlink_priority(dev) >= priority) {
312 priority = udev_device_get_devlink_priority(dev);
313 util_strlcpy(target, udev_device_get_devnode(dev), sizeof(target));
318 /* another device, read priority from database */
319 dev_db = udev_device_new_from_syspath(udev, device->name);
322 devnode = udev_device_get_devnode(dev_db);
323 if (devnode != NULL) {
324 if (strcmp(devnode, slink) == 0) {
325 info(udev, "'%s' is a device node of '%s', skip link update\n",
326 devnode, device->name);
328 info(udev, "compare priority of '%s' %i > %i\n",
329 udev_device_get_devpath(dev_db),
330 udev_device_get_devlink_priority(dev_db),
332 if (target[0] == '\0' || udev_device_get_devlink_priority(dev_db) > priority) {
333 priority = udev_device_get_devlink_priority(dev_db);
334 util_strlcpy(target, devnode, sizeof(target));
338 udev_device_unref(dev_db);
340 name_list_cleanup(udev, &name_list);
342 if (target[0] == '\0') {
343 info(udev, "no current target for '%s' found\n", slink);
348 /* create symlink to the target with the highest priority */
349 info(udev, "'%s' with target '%s' has the highest priority %i, create it\n", slink, target, priority);
351 create_path(udev, slink);
352 node_symlink(udev, target, slink);
358 void udev_node_update_old_links(struct udev_device *dev, struct udev_device *dev_old, int test)
360 struct udev *udev = udev_device_get_udev(dev);
361 struct udev_list_entry *list_entry;
362 const char *devnode_old;
364 /* update possible left-over symlinks */
365 udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev_old)) {
366 struct udev_list_entry *list_entry_current;
368 udev_list_entry_foreach(list_entry_current, udev_device_get_devlinks_list_entry(dev)) {
369 if (strcmp(udev_list_entry_get_name(list_entry_current),
370 udev_list_entry_get_name(list_entry)) == 0)
373 /* link does no longer belong to this device */
374 info(udev, "update old symlink '%s' no longer belonging to '%s'\n",
375 udev_list_entry_get_name(list_entry), udev_device_get_devpath(dev));
376 update_link(dev, udev_list_entry_get_name(list_entry), test);
380 * if the node name has changed, delete the node,
381 * and possibly restore a symlink of another device
383 devnode_old = udev_device_get_devnode(dev_old);
384 if (devnode_old != NULL) {
385 const char *devnode = udev_device_get_devnode(dev);
387 if (devnode != NULL && strcmp(devnode_old, devnode) != 0)
388 update_link(dev, devnode_old, test);
392 int udev_node_add(struct udev_device *dev, mode_t mode, const char *owner, const char *group, int test)
394 struct udev *udev = udev_device_get_udev(dev);
399 struct udev_list_entry *list_entry;
402 create_path(udev, udev_device_get_devnode(dev));
404 if (strcmp(owner, "root") == 0)
410 id = strtoul(owner, &endptr, 10);
411 if (endptr[0] == '\0')
414 uid = lookup_user(udev, owner);
417 if (strcmp(group, "root") == 0)
423 id = strtoul(group, &endptr, 10);
424 if (endptr[0] == '\0')
427 gid = lookup_group(udev, group);
430 info(udev, "creating device node '%s', devnum=%d:%d, mode=%#o, uid=%d, gid=%d\n",
431 udev_device_get_devnode(dev),
432 major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev)),
436 if (udev_node_mknod(dev, NULL, makedev(0,0), mode, uid, gid) != 0) {
441 /* create all_partitions if requested */
442 num = udev_device_get_num_fake_partitions(dev);
444 info(udev, "creating device partition nodes '%s[1-%i]'\n", udev_device_get_devnode(dev), num);
446 for (i = 1; i <= num; i++) {
447 char partitionname[UTIL_PATH_SIZE];
450 snprintf(partitionname, sizeof(partitionname), "%s%d",
451 udev_device_get_devnode(dev), i);
452 partitionname[sizeof(partitionname)-1] = '\0';
453 part_devnum = makedev(major(udev_device_get_devnum(dev)),
454 minor(udev_device_get_devnum(dev)) + i);
455 udev_node_mknod(dev, partitionname, part_devnum, mode, uid, gid);
460 /* add node and to name index */
461 name_index(udev, udev_device_get_devpath(dev), udev_device_get_devnode(dev), 1, test);
463 /* create/update symlinks, add symlinks to name index */
464 udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) {
465 name_index(udev, udev_device_get_devpath(dev), udev_list_entry_get_name(list_entry), 1, test);
466 update_link(dev, udev_list_entry_get_name(list_entry), test);
472 extern int udev_node_remove(struct udev_device *dev, int test)
474 struct udev *udev = udev_device_get_udev(dev);
475 struct udev_list_entry *list_entry;
477 char partitionname[UTIL_PATH_SIZE];
482 /* remove node from name index */
483 name_index(udev, udev_device_get_devpath(dev), udev_device_get_devnode(dev), 0, test);
485 /* remove,update symlinks, remove symlinks from name index */
486 udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) {
487 name_index(udev, udev_device_get_devpath(dev), udev_list_entry_get_name(list_entry), 0, test);
488 update_link(dev, udev_list_entry_get_name(list_entry), test);
491 devnode = udev_device_get_devnode(dev);
494 if (stat(devnode, &stats) != 0) {
495 info(udev, "device node '%s' not found\n", devnode);
498 if (stats.st_rdev != udev_device_get_devnum(dev)) {
499 info(udev, "device node '%s' points to a different device, skip removal\n", devnode);
503 info(udev, "removing device node '%s'\n", devnode);
505 err = unlink_secure(udev, devnode);
509 num = udev_device_get_num_fake_partitions(dev);
513 info(udev, "removing all_partitions '%s[1-%i]'\n", devnode, num);
516 for (i = 1; i <= num; i++) {
517 snprintf(partitionname, sizeof(partitionname), "%s%d", devnode, i);
518 partitionname[sizeof(partitionname)-1] = '\0';
520 unlink_secure(udev, partitionname);
523 delete_path(udev, devnode);