2 * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
3 * Copyright (C) 2004-2006 Kay Sievers <kay.sievers@vrfy.org>
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.
30 #include <sys/types.h>
33 #include "udev_rules.h"
34 #include "udev_selinux.h"
36 #define TMP_FILE_EXT ".udev-tmp"
38 int udev_node_mknod(struct udevice *udev, const char *file, dev_t devt, mode_t mode, uid_t uid, gid_t gid)
40 char file_tmp[PATH_SIZE + sizeof(TMP_FILE_EXT)];
44 if (major(devt) != 0 && strcmp(udev->dev->subsystem, "block") == 0)
49 if (lstat(file, &stats) == 0) {
50 if ((stats.st_mode & S_IFMT) == (mode & S_IFMT) && (stats.st_rdev == devt)) {
51 info("preserve file '%s', because it has correct dev_t", file);
52 selinux_setfilecon(file, udev->dev->kernel, stats.st_mode);
56 selinux_setfscreatecon(file, udev->dev->kernel, mode);
57 retval = mknod(file, mode, devt);
58 selinux_resetfscreatecon();
63 info("atomically replace '%s'", file);
64 strlcpy(file_tmp, file, sizeof(file_tmp));
65 strlcat(file_tmp, TMP_FILE_EXT, sizeof(file_tmp));
67 selinux_setfscreatecon(file_tmp, udev->dev->kernel, mode);
68 retval = mknod(file_tmp, mode, devt);
69 selinux_resetfscreatecon();
71 err("mknod(%s, %#o, %u, %u) failed: %s",
72 file_tmp, mode, major(devt), minor(devt), strerror(errno));
75 retval = rename(file_tmp, file);
77 err("rename(%s, %s) failed: %s",
78 file_tmp, file, strerror(errno));
84 dbg("chmod(%s, %#o)", file, mode);
85 if (chmod(file, mode) != 0) {
86 err("chmod(%s, %#o) failed: %s", file, mode, strerror(errno));
90 if (uid != 0 || gid != 0) {
91 dbg("chown(%s, %u, %u)", file, uid, gid);
92 if (chown(file, uid, gid) != 0) {
93 err("chown(%s, %u, %u) failed: %s",
94 file, uid, gid, strerror(errno));
102 static int node_symlink(const char *node, const char *slink)
105 char target[PATH_SIZE] = "";
106 char slink_tmp[PATH_SIZE + sizeof(TMP_FILE_EXT)];
112 /* use relative link */
113 while (node[i] && (node[i] == slink[i])) {
118 while (slink[i] != '\0') {
120 strlcat(target, "../", sizeof(target));
123 strlcat(target, &node[tail], sizeof(target));
125 /* preserve link with correct target, do not replace node of other device */
126 if (lstat(slink, &stats) == 0) {
127 if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
130 info("found existing node instead of symlink '%s'", slink);
131 if (lstat(node, &stats2) == 0) {
132 if ((stats.st_mode & S_IFMT) == (stats2.st_mode & S_IFMT) &&
133 stats.st_rdev == stats2.st_rdev) {
134 info("replace device node '%s' with symlink to our node '%s'", slink, node);
136 err("device node '%s' already exists, link '%s' will not overwrite it", node, slink);
140 } else if (S_ISLNK(stats.st_mode)) {
143 info("found existing symlink '%s'", slink);
144 len = readlink(slink, buf, sizeof(buf));
147 if (strcmp(target, buf) == 0) {
148 info("preserve already existing symlink '%s' to '%s'", slink, target);
149 selinux_setfilecon(slink, NULL, S_IFLNK);
155 info("creating symlink '%s' to '%s'", slink, target);
156 selinux_setfscreatecon(slink, NULL, S_IFLNK);
157 retval = symlink(target, slink);
158 selinux_resetfscreatecon();
163 info("atomically replace '%s'", slink);
164 strlcpy(slink_tmp, slink, sizeof(slink_tmp));
165 strlcat(slink_tmp, TMP_FILE_EXT, sizeof(slink_tmp));
167 selinux_setfscreatecon(slink_tmp, NULL, S_IFLNK);
168 retval = symlink(target, slink_tmp);
169 selinux_resetfscreatecon();
171 err("symlink(%s, %s) failed: %s", target, slink_tmp, strerror(errno));
174 retval = rename(slink_tmp, slink);
176 err("rename(%s, %s) failed: %s", slink_tmp, slink, strerror(errno));
184 static int update_link(struct udevice *udev, const char *name)
186 LIST_HEAD(name_list);
187 char slink[PATH_SIZE];
188 char node[PATH_SIZE];
189 struct udevice *udev_db;
190 struct name_entry *device;
191 char target[PATH_MAX] = "";
196 strlcpy(slink, udev_root, sizeof(slink));
197 strlcat(slink, "/", sizeof(slink));
198 strlcat(slink, name, sizeof(slink));
200 count = udev_db_get_devices_by_name(name, &name_list);
201 info("found %i devices with name '%s'", count, name);
203 /* if we don't have a reference, delete it */
205 info("no reference left, remove '%s'", name);
206 if (!udev->test_run) {
213 /* find the device with the highest priority */
214 list_for_each_entry(device, &name_list, node) {
215 info("found '%s' for '%s'", device->name, name);
217 /* did we find ourself? we win, if we have the same priority */
218 if (strcmp(udev->dev->devpath, device->name) == 0) {
219 info("compare (our own) priority of '%s' %i >= %i",
220 udev->dev->devpath, udev->link_priority, priority);
221 if (target[0] == '\0' || udev->link_priority >= priority) {
222 priority = udev->link_priority;
223 strlcpy(target, udev->name, sizeof(target));
228 /* or something else, then read priority from database */
229 udev_db = udev_device_init(NULL);
232 if (udev_db_get_device(udev_db, device->name) == 0) {
233 info("compare priority of '%s' %i > %i",
234 udev_db->dev->devpath, udev_db->link_priority, priority);
235 if (target[0] == '\0' || udev_db->link_priority > priority) {
236 priority = udev_db->link_priority;
237 strlcpy(target, udev_db->name, sizeof(target));
240 udev_device_cleanup(udev_db);
242 name_list_cleanup(&name_list);
244 if (target[0] == '\0') {
245 err("missing target for '%s'", name);
250 /* create symlink to the target with the highest priority */
251 strlcpy(node, udev_root, sizeof(node));
252 strlcat(node, "/", sizeof(node));
253 strlcat(node, target, sizeof(node));
254 info("'%s' with target '%s' has the highest priority %i, create it", name, target, priority);
255 if (!udev->test_run) {
257 node_symlink(node, slink);
263 void udev_node_update_symlinks(struct udevice *udev, struct udevice *udev_old)
265 struct name_entry *name_loop;
266 char symlinks[PATH_SIZE] = "";
268 list_for_each_entry(name_loop, &udev->symlink_list, node) {
269 info("update symlink '%s' of '%s'", name_loop->name, udev->dev->devpath);
270 update_link(udev, name_loop->name);
271 strlcat(symlinks, udev_root, sizeof(symlinks));
272 strlcat(symlinks, "/", sizeof(symlinks));
273 strlcat(symlinks, name_loop->name, sizeof(symlinks));
274 strlcat(symlinks, " ", sizeof(symlinks));
277 /* export symlinks to environment */
278 remove_trailing_chars(symlinks, ' ');
279 if (symlinks[0] != '\0')
280 setenv("DEVLINKS", symlinks, 1);
282 /* update possible left-over symlinks (device metadata changed) */
283 if (udev_old != NULL) {
284 struct name_entry *link_loop;
285 struct name_entry *link_old_loop;
288 /* remove current symlinks from old list */
289 list_for_each_entry(link_old_loop, &udev_old->symlink_list, node) {
291 list_for_each_entry(link_loop, &udev->symlink_list, node) {
292 if (strcmp(link_old_loop->name, link_loop->name) == 0) {
298 /* link does no longer belong to this device */
299 info("update old symlink '%s' no longer belonging to '%s'",
300 link_old_loop->name, udev->dev->devpath);
301 update_link(udev, link_old_loop->name);
306 * if the node name has changed, delete the node,
307 * or possibly restore a symlink of another device
309 if (strcmp(udev->name, udev_old->name) != 0)
310 update_link(udev, udev_old->name);
314 int udev_node_add(struct udevice *udev)
316 char filename[PATH_SIZE];
322 strlcpy(filename, udev_root, sizeof(filename));
323 strlcat(filename, "/", sizeof(filename));
324 strlcat(filename, udev->name, sizeof(filename));
325 create_path(filename);
327 if (strcmp(udev->owner, "root") == 0)
333 id = strtoul(udev->owner, &endptr, 10);
334 if (endptr[0] == '\0')
337 uid = lookup_user(udev->owner);
340 if (strcmp(udev->group, "root") == 0)
346 id = strtoul(udev->group, &endptr, 10);
347 if (endptr[0] == '\0')
350 gid = lookup_group(udev->group);
353 info("creating device node '%s', major=%d, minor=%d, mode=%#o, uid=%d, gid=%d",
354 filename, major(udev->devt), minor(udev->devt), udev->mode, uid, gid);
357 if (udev_node_mknod(udev, filename, udev->devt, udev->mode, uid, gid) != 0) {
362 setenv("DEVNAME", filename, 1);
364 /* create all_partitions if requested */
365 if (udev->partitions) {
366 char partitionname[PATH_SIZE];
370 /* take the maximum registered minor range */
371 attr = sysfs_attr_get_value(udev->dev->devpath, "range");
375 udev->partitions = range-1;
377 info("creating device partition nodes '%s[1-%i]'", filename, udev->partitions);
378 if (!udev->test_run) {
379 for (i = 1; i <= udev->partitions; i++) {
382 snprintf(partitionname, sizeof(partitionname), "%s%d", filename, i);
383 partitionname[sizeof(partitionname)-1] = '\0';
384 part_devt = makedev(major(udev->devt), minor(udev->devt) + i);
385 udev_node_mknod(udev, partitionname, part_devt, udev->mode, uid, gid);
393 int udev_node_remove(struct udevice *udev)
395 char filename[PATH_SIZE];
396 char partitionname[PATH_SIZE];
401 strlcpy(filename, udev_root, sizeof(filename));
402 strlcat(filename, "/", sizeof(filename));
403 strlcat(filename, udev->name, sizeof(filename));
404 if (stat(filename, &stats) != 0) {
405 dbg("device node '%s' not found", filename);
408 if (udev->devt && stats.st_rdev != udev->devt) {
409 info("device node '%s' points to a different device, skip removal", filename);
413 info("removing device node '%s'", filename);
415 retval = unlink_secure(filename);
419 setenv("DEVNAME", filename, 1);
420 num = udev->partitions;
424 info("removing all_partitions '%s[1-%i]'", filename, num);
427 for (i = 1; i <= num; i++) {
428 snprintf(partitionname, sizeof(partitionname), "%s%d", filename, i);
429 partitionname[sizeof(partitionname)-1] = '\0';
431 unlink_secure(partitionname);
434 delete_path(filename);