2 * Copyright (c) 2009 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Alex Hornung <ahornung@gmail.com>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/types.h>
39 #include <sys/spinlock2.h>
40 #include <sys/fcntl.h>
41 #include <sys/device.h>
42 #include <sys/mount.h>
43 #include <sys/devfs.h>
44 #include <sys/devfs_rules.h>
46 MALLOC_DECLARE(M_DEVFS);
48 static d_open_t devfs_dev_open;
49 static d_close_t devfs_dev_close;
50 static d_ioctl_t devfs_dev_ioctl;
52 static struct devfs_rule *devfs_rule_alloc(struct devfs_rule_ioctl *);
53 static void devfs_rule_free(struct devfs_rule *);
54 static int devfs_rule_insert(struct devfs_rule_ioctl *);
55 static void devfs_rule_remove(struct devfs_rule *);
56 static int devfs_rule_clear(struct devfs_rule_ioctl *);
57 static void devfs_rule_create_link(struct devfs_node *, struct devfs_rule *);
58 static int devfs_rule_checkname(struct devfs_rule *, struct devfs_node *);
60 static struct objcache *devfs_rule_cache;
61 static struct lock devfs_rule_lock;
63 static struct objcache_malloc_args devfs_rule_malloc_args = {
64 sizeof(struct devfs_rule), M_DEVFS };
66 static cdev_t devfs_dev;
67 static struct devfs_rule_head devfs_rule_list =
68 TAILQ_HEAD_INITIALIZER(devfs_rule_list);
70 static struct dev_ops devfs_dev_ops = {
72 .d_open = devfs_dev_open,
73 .d_close = devfs_dev_close,
74 .d_ioctl = devfs_dev_ioctl
78 static struct devfs_rule *
79 devfs_rule_alloc(struct devfs_rule_ioctl *templ)
81 struct devfs_rule *rule;
84 rule = objcache_get(devfs_rule_cache, M_WAITOK);
85 memset(rule, 0, sizeof(struct devfs_rule));
87 if (templ->mntpoint == NULL)
91 len = strlen(templ->mntpoint);
96 rule->mntpoint = kstrdup(templ->mntpoint, M_DEVFS);
97 rule->mntpointlen = len;
99 if (templ->rule_type & DEVFS_RULE_NAME) {
100 if (templ->name == NULL)
104 len = strlen(templ->name);
109 rule->name = kstrdup(templ->name, M_DEVFS);
113 if (templ->rule_cmd & DEVFS_RULE_LINK) {
114 if (templ->linkname == NULL)
118 len = strlen(templ->linkname);
123 rule->linkname = kstrdup(templ->linkname, M_DEVFS);
124 rule->linknamlen = len;
127 rule->rule_type = templ->rule_type;
128 rule->rule_cmd = templ->rule_cmd;
129 rule->dev_type = templ->dev_type;
130 rule->mode = templ->mode;
131 rule->uid = templ->uid;
132 rule->gid = templ->gid;
137 devfs_rule_free(rule);
143 devfs_rule_free(struct devfs_rule *rule)
145 if (rule->mntpoint != NULL) {
146 kfree(rule->mntpoint, M_DEVFS);
149 if (rule->name != NULL) {
150 kfree(rule->name, M_DEVFS);
153 if (rule->linkname != NULL) {
154 kfree(rule->linkname, M_DEVFS);
156 objcache_put(devfs_rule_cache, rule);
161 devfs_rule_insert(struct devfs_rule_ioctl *templ)
163 struct devfs_rule *rule;
165 rule = devfs_rule_alloc(templ);
169 lockmgr(&devfs_rule_lock, LK_EXCLUSIVE);
170 TAILQ_INSERT_TAIL(&devfs_rule_list, rule, link);
171 lockmgr(&devfs_rule_lock, LK_RELEASE);
178 devfs_rule_remove(struct devfs_rule *rule)
180 TAILQ_REMOVE(&devfs_rule_list, rule, link);
181 devfs_rule_free(rule);
186 devfs_rule_clear(struct devfs_rule_ioctl *templ)
188 struct devfs_rule *rule1, *rule2;
191 if (templ->mntpoint == NULL)
194 mntpointlen = strlen(templ->mntpoint);
195 if (mntpointlen == 0)
198 lockmgr(&devfs_rule_lock, LK_EXCLUSIVE);
199 TAILQ_FOREACH_MUTABLE(rule1, &devfs_rule_list, link, rule2) {
200 if ((templ->mntpoint[0] == '*') ||
201 ( (mntpointlen == rule1->mntpointlen) &&
202 (!memcmp(templ->mntpoint, rule1->mntpoint, mntpointlen)) )) {
203 devfs_rule_remove(rule1);
206 lockmgr(&devfs_rule_lock, LK_RELEASE);
213 devfs_rule_reset_node(struct devfs_node *node, void *unused)
216 * Don't blindly unhide all devices, some, like unix98 pty masters,
217 * haven't been hidden by a rule.
219 if (node->flags & DEVFS_RULE_HIDDEN)
220 node->flags &= ~(DEVFS_HIDDEN | DEVFS_RULE_HIDDEN);
222 if ((node->node_type == Nlink) && (node->flags & DEVFS_RULE_CREATED)) {
223 KKASSERT(node->link_target);
224 node->flags &= ~DEVFS_RULE_CREATED;
225 --node->link_target->nlinks;
227 } else if ((node->node_type == Ndev) && (node->d_dev)) {
228 node->uid = node->d_dev->si_uid;
229 node->gid = node->d_dev->si_gid;
230 node->mode = node->d_dev->si_perms;
237 devfs_rule_create_link(struct devfs_node *node, struct devfs_rule *rule)
241 char *name, name_buf[PATH_MAX], buf[PATH_MAX];
243 if (rule->name[rule->namlen-1] == '*') {
244 devfs_resolve_name_path(rule->name, name_buf, &path, &name);
247 ksnprintf(buf, sizeof(buf), "%s%s",
248 rule->linkname, node->d_dir.d_name+len);
249 devfs_alias_create(buf, node, 1);
251 devfs_alias_create(rule->linkname, node, 1);
256 devfs_rule_check_apply(struct devfs_node *node, void *unused)
258 struct devfs_rule *rule;
259 struct mount *mp = node->mp;
262 /* Check if it is locked already. if not, we acquire the devfs lock */
263 if ((lockstatus(&devfs_rule_lock, curthread)) != LK_EXCLUSIVE) {
264 lockmgr(&devfs_rule_lock, LK_EXCLUSIVE);
268 TAILQ_FOREACH(rule, &devfs_rule_list, link) {
270 * Skip this rule if it is only intended for jailed mount points
271 * and the current mount point isn't jailed
273 if ((rule->rule_type & DEVFS_RULE_JAIL) &&
274 (!(DEVFS_MNTDATA(mp)->jailed)) )
278 * Skip this rule if it is not intended for jailed mount points
279 * and the current mount point is jailed.
281 if (!(rule->rule_type & DEVFS_RULE_JAIL) &&
282 (DEVFS_MNTDATA(mp)->jailed))
286 * Skip this rule if the mount point specified in the rule doesn't
287 * match the mount point of the node
289 if ((rule->mntpoint[0] != '*') &&
290 (strcmp(rule->mntpoint, mp->mnt_stat.f_mntonname)))
294 * Skip this rule if this is a by-type rule and the device flags
295 * don't match the specified device type in the rule
297 if ((rule->rule_type & DEVFS_RULE_TYPE) &&
298 ( (rule->dev_type == 0) || (!dev_is_good(node->d_dev)) ||
299 (!(dev_dflags(node->d_dev) & rule->dev_type))) )
303 * Skip this rule if this is a by-name rule and the node name
304 * doesn't match the wildcard string in the rule
306 if ((rule->rule_type & DEVFS_RULE_NAME) &&
307 (!devfs_rule_checkname(rule, node)) )
310 if (rule->rule_cmd & DEVFS_RULE_HIDE) {
312 * If we should hide the device, we just apply the relevant
313 * hide flag to the node and let devfs do the rest in the
316 if ((node->d_dir.d_namlen == 5) &&
317 (!memcmp(node->d_dir.d_name, "devfs", 5))) {
319 * Magically avoid /dev/devfs from being hidden, so that one
320 * can still use the rule system even after a "* hide".
324 node->flags |= (DEVFS_HIDDEN | DEVFS_RULE_HIDDEN);
325 } else if (rule->rule_cmd & DEVFS_RULE_SHOW) {
327 * Show rule just means that the node should not be hidden, so
328 * what we do is clear the hide flag from the node.
330 node->flags &= ~DEVFS_HIDDEN;
331 } else if (rule->rule_cmd & DEVFS_RULE_LINK) {
333 * This is a LINK rule, so we tell devfs to create
334 * a link with the correct name to this node.
336 devfs_rule_create_link(node, rule);
338 devfs_alias_create(rule->linkname, node, 1);
340 } else if (rule->rule_cmd & DEVFS_RULE_PERM) {
342 * This is a normal ownership/permission rule. We
343 * just apply the permissions and ownership and
346 node->mode = rule->mode;
347 node->uid = rule->uid;
348 node->gid = rule->gid;
352 /* If we acquired the lock, we also get rid of it */
354 lockmgr(&devfs_rule_lock, LK_RELEASE);
361 devfs_rule_checkname(struct devfs_rule *rule, struct devfs_node *node)
363 struct devfs_node *parent = DEVFS_MNTDATA(node->mp)->root_node;
365 char *name, name_buf[PATH_MAX];
368 devfs_resolve_name_path(rule->name, name_buf, &path, &name);
369 parent = devfs_resolve_or_create_path(parent, path, 0);
372 return 0; /* no match */
374 /* Check if node is a child of the parent we found */
375 if (node->parent != parent)
376 return 0; /* no match */
379 if (rule->rule_type & DEVFS_RULE_LINK)
380 no_match = memcmp(name, node->d_dir.d_name, strlen(name));
383 no_match = devfs_WildCaseCmp(name, node->d_dir.d_name);
390 devfs_dev_open(struct dev_open_args *ap)
393 * Only allow read-write access.
395 if (((ap->a_oflags & FWRITE) == 0) || ((ap->a_oflags & FREAD) == 0))
399 * We don't allow nonblocking access.
401 if ((ap->a_oflags & O_NONBLOCK) != 0) {
402 devfs_debug(DEVFS_DEBUG_SHOW, "devfs_dev: can't do nonblocking access\n");
411 devfs_dev_close(struct dev_close_args *ap)
418 devfs_dev_ioctl(struct dev_ioctl_args *ap)
421 struct devfs_rule_ioctl *rule;
424 rule = (struct devfs_rule_ioctl *)ap->a_data;
428 error = devfs_rule_insert(rule);
431 case DEVFS_RULE_APPLY:
432 if (rule->mntpoint == NULL)
435 devfs_apply_rules(rule->mntpoint);
438 case DEVFS_RULE_CLEAR:
439 error = devfs_rule_clear(rule);
442 case DEVFS_RULE_RESET:
443 if (rule->mntpoint == NULL)
446 devfs_reset_rules(rule->mntpoint);
450 error = ENOTTY; /* Inappropriate ioctl for device */
459 devfs_dev_init(void *unused)
461 lockinit(&devfs_rule_lock, "devfs_rule lock", 0, 0);
463 devfs_rule_cache = objcache_create("devfs-rule-cache", 0, 0,
465 objcache_malloc_alloc,
466 objcache_malloc_free,
467 &devfs_rule_malloc_args );
469 devfs_dev = make_dev(&devfs_dev_ops,
479 devfs_dev_uninit(void *unused)
481 /* XXX: destroy all rules first */
482 destroy_dev(devfs_dev);
483 objcache_destroy(devfs_rule_cache);
487 SYSINIT(devfsdev,SI_SUB_DRIVERS,SI_ORDER_FIRST,devfs_dev_init,NULL);
488 SYSUNINIT(devfsdev, SI_SUB_DRIVERS,SI_ORDER_FIRST,devfs_dev_uninit, NULL);