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fe7752ba DW |
1 | /* auditfilter.c -- filtering of audit events |
2 | * | |
3 | * Copyright 2003-2004 Red Hat, Inc. | |
4 | * Copyright 2005 Hewlett-Packard Development Company, L.P. | |
5 | * Copyright 2005 IBM Corporation | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
20 | */ | |
21 | ||
22 | #include <linux/kernel.h> | |
23 | #include <linux/audit.h> | |
24 | #include <linux/kthread.h> | |
f368c07d AG |
25 | #include <linux/mutex.h> |
26 | #include <linux/fs.h> | |
27 | #include <linux/namei.h> | |
fe7752ba | 28 | #include <linux/netlink.h> |
f368c07d AG |
29 | #include <linux/sched.h> |
30 | #include <linux/inotify.h> | |
3dc7e315 | 31 | #include <linux/selinux.h> |
fe7752ba DW |
32 | #include "audit.h" |
33 | ||
f368c07d AG |
34 | /* |
35 | * Locking model: | |
36 | * | |
37 | * audit_filter_mutex: | |
38 | * Synchronizes writes and blocking reads of audit's filterlist | |
39 | * data. Rcu is used to traverse the filterlist and access | |
40 | * contents of structs audit_entry, audit_watch and opaque | |
41 | * selinux rules during filtering. If modified, these structures | |
42 | * must be copied and replace their counterparts in the filterlist. | |
43 | * An audit_parent struct is not accessed during filtering, so may | |
44 | * be written directly provided audit_filter_mutex is held. | |
45 | */ | |
46 | ||
47 | /* | |
48 | * Reference counting: | |
49 | * | |
50 | * audit_parent: lifetime is from audit_init_parent() to receipt of an IN_IGNORED | |
51 | * event. Each audit_watch holds a reference to its associated parent. | |
52 | * | |
53 | * audit_watch: if added to lists, lifetime is from audit_init_watch() to | |
54 | * audit_remove_watch(). Additionally, an audit_watch may exist | |
55 | * temporarily to assist in searching existing filter data. Each | |
56 | * audit_krule holds a reference to its associated watch. | |
57 | */ | |
58 | ||
59 | struct audit_parent { | |
60 | struct list_head ilist; /* entry in inotify registration list */ | |
61 | struct list_head watches; /* associated watches */ | |
62 | struct inotify_watch wdata; /* inotify watch data */ | |
63 | unsigned flags; /* status flags */ | |
64 | }; | |
65 | ||
66 | /* | |
67 | * audit_parent status flags: | |
68 | * | |
69 | * AUDIT_PARENT_INVALID - set anytime rules/watches are auto-removed due to | |
70 | * a filesystem event to ensure we're adding audit watches to a valid parent. | |
71 | * Technically not needed for IN_DELETE_SELF or IN_UNMOUNT events, as we cannot | |
72 | * receive them while we have nameidata, but must be used for IN_MOVE_SELF which | |
73 | * we can receive while holding nameidata. | |
74 | */ | |
75 | #define AUDIT_PARENT_INVALID 0x001 | |
76 | ||
77 | /* Audit filter lists, defined in <linux/audit.h> */ | |
fe7752ba DW |
78 | struct list_head audit_filter_list[AUDIT_NR_FILTERS] = { |
79 | LIST_HEAD_INIT(audit_filter_list[0]), | |
80 | LIST_HEAD_INIT(audit_filter_list[1]), | |
81 | LIST_HEAD_INIT(audit_filter_list[2]), | |
82 | LIST_HEAD_INIT(audit_filter_list[3]), | |
83 | LIST_HEAD_INIT(audit_filter_list[4]), | |
84 | LIST_HEAD_INIT(audit_filter_list[5]), | |
85 | #if AUDIT_NR_FILTERS != 6 | |
86 | #error Fix audit_filter_list initialiser | |
87 | #endif | |
88 | }; | |
89 | ||
f368c07d AG |
90 | static DEFINE_MUTEX(audit_filter_mutex); |
91 | ||
92 | /* Inotify handle */ | |
93 | extern struct inotify_handle *audit_ih; | |
94 | ||
95 | /* Inotify events we care about. */ | |
96 | #define AUDIT_IN_WATCH IN_MOVE|IN_CREATE|IN_DELETE|IN_DELETE_SELF|IN_MOVE_SELF | |
97 | ||
98 | void audit_free_parent(struct inotify_watch *i_watch) | |
99 | { | |
100 | struct audit_parent *parent; | |
101 | ||
102 | parent = container_of(i_watch, struct audit_parent, wdata); | |
103 | WARN_ON(!list_empty(&parent->watches)); | |
104 | kfree(parent); | |
105 | } | |
106 | ||
107 | static inline void audit_get_watch(struct audit_watch *watch) | |
108 | { | |
109 | atomic_inc(&watch->count); | |
110 | } | |
111 | ||
112 | static void audit_put_watch(struct audit_watch *watch) | |
113 | { | |
114 | if (atomic_dec_and_test(&watch->count)) { | |
115 | WARN_ON(watch->parent); | |
116 | WARN_ON(!list_empty(&watch->rules)); | |
117 | kfree(watch->path); | |
118 | kfree(watch); | |
119 | } | |
120 | } | |
121 | ||
122 | static void audit_remove_watch(struct audit_watch *watch) | |
123 | { | |
124 | list_del(&watch->wlist); | |
125 | put_inotify_watch(&watch->parent->wdata); | |
126 | watch->parent = NULL; | |
127 | audit_put_watch(watch); /* match initial get */ | |
128 | } | |
129 | ||
93315ed6 | 130 | static inline void audit_free_rule(struct audit_entry *e) |
fe7752ba | 131 | { |
3dc7e315 | 132 | int i; |
f368c07d AG |
133 | |
134 | /* some rules don't have associated watches */ | |
135 | if (e->rule.watch) | |
136 | audit_put_watch(e->rule.watch); | |
3dc7e315 DG |
137 | if (e->rule.fields) |
138 | for (i = 0; i < e->rule.field_count; i++) { | |
139 | struct audit_field *f = &e->rule.fields[i]; | |
140 | kfree(f->se_str); | |
141 | selinux_audit_rule_free(f->se_rule); | |
142 | } | |
93315ed6 | 143 | kfree(e->rule.fields); |
5adc8a6a | 144 | kfree(e->rule.filterkey); |
93315ed6 AG |
145 | kfree(e); |
146 | } | |
147 | ||
148 | static inline void audit_free_rule_rcu(struct rcu_head *head) | |
149 | { | |
150 | struct audit_entry *e = container_of(head, struct audit_entry, rcu); | |
151 | audit_free_rule(e); | |
152 | } | |
153 | ||
f368c07d AG |
154 | /* Initialize a parent watch entry. */ |
155 | static struct audit_parent *audit_init_parent(struct nameidata *ndp) | |
156 | { | |
157 | struct audit_parent *parent; | |
158 | s32 wd; | |
159 | ||
160 | parent = kzalloc(sizeof(*parent), GFP_KERNEL); | |
161 | if (unlikely(!parent)) | |
162 | return ERR_PTR(-ENOMEM); | |
163 | ||
164 | INIT_LIST_HEAD(&parent->watches); | |
165 | parent->flags = 0; | |
166 | ||
167 | inotify_init_watch(&parent->wdata); | |
168 | /* grab a ref so inotify watch hangs around until we take audit_filter_mutex */ | |
169 | get_inotify_watch(&parent->wdata); | |
170 | wd = inotify_add_watch(audit_ih, &parent->wdata, ndp->dentry->d_inode, | |
171 | AUDIT_IN_WATCH); | |
172 | if (wd < 0) { | |
173 | audit_free_parent(&parent->wdata); | |
174 | return ERR_PTR(wd); | |
175 | } | |
176 | ||
177 | return parent; | |
178 | } | |
179 | ||
180 | /* Initialize a watch entry. */ | |
181 | static struct audit_watch *audit_init_watch(char *path) | |
182 | { | |
183 | struct audit_watch *watch; | |
184 | ||
185 | watch = kzalloc(sizeof(*watch), GFP_KERNEL); | |
186 | if (unlikely(!watch)) | |
187 | return ERR_PTR(-ENOMEM); | |
188 | ||
189 | INIT_LIST_HEAD(&watch->rules); | |
190 | atomic_set(&watch->count, 1); | |
191 | watch->path = path; | |
192 | watch->dev = (dev_t)-1; | |
193 | watch->ino = (unsigned long)-1; | |
194 | ||
195 | return watch; | |
196 | } | |
197 | ||
3dc7e315 DG |
198 | /* Initialize an audit filterlist entry. */ |
199 | static inline struct audit_entry *audit_init_entry(u32 field_count) | |
200 | { | |
201 | struct audit_entry *entry; | |
202 | struct audit_field *fields; | |
203 | ||
204 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
205 | if (unlikely(!entry)) | |
206 | return NULL; | |
207 | ||
208 | fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL); | |
209 | if (unlikely(!fields)) { | |
210 | kfree(entry); | |
211 | return NULL; | |
212 | } | |
213 | entry->rule.fields = fields; | |
214 | ||
215 | return entry; | |
216 | } | |
217 | ||
93315ed6 AG |
218 | /* Unpack a filter field's string representation from user-space |
219 | * buffer. */ | |
3dc7e315 | 220 | static char *audit_unpack_string(void **bufp, size_t *remain, size_t len) |
93315ed6 AG |
221 | { |
222 | char *str; | |
223 | ||
224 | if (!*bufp || (len == 0) || (len > *remain)) | |
225 | return ERR_PTR(-EINVAL); | |
226 | ||
227 | /* Of the currently implemented string fields, PATH_MAX | |
228 | * defines the longest valid length. | |
229 | */ | |
230 | if (len > PATH_MAX) | |
231 | return ERR_PTR(-ENAMETOOLONG); | |
232 | ||
233 | str = kmalloc(len + 1, GFP_KERNEL); | |
234 | if (unlikely(!str)) | |
235 | return ERR_PTR(-ENOMEM); | |
236 | ||
237 | memcpy(str, *bufp, len); | |
238 | str[len] = 0; | |
239 | *bufp += len; | |
240 | *remain -= len; | |
241 | ||
242 | return str; | |
243 | } | |
244 | ||
f368c07d AG |
245 | /* Translate an inode field to kernel respresentation. */ |
246 | static inline int audit_to_inode(struct audit_krule *krule, | |
247 | struct audit_field *f) | |
248 | { | |
249 | if (krule->listnr != AUDIT_FILTER_EXIT || | |
250 | krule->watch || krule->inode_f) | |
251 | return -EINVAL; | |
252 | ||
253 | krule->inode_f = f; | |
254 | return 0; | |
255 | } | |
256 | ||
257 | /* Translate a watch string to kernel respresentation. */ | |
258 | static int audit_to_watch(struct audit_krule *krule, char *path, int len, | |
259 | u32 op) | |
260 | { | |
261 | struct audit_watch *watch; | |
262 | ||
263 | if (!audit_ih) | |
264 | return -EOPNOTSUPP; | |
265 | ||
266 | if (path[0] != '/' || path[len-1] == '/' || | |
267 | krule->listnr != AUDIT_FILTER_EXIT || | |
268 | op & ~AUDIT_EQUAL || | |
269 | krule->inode_f || krule->watch) /* 1 inode # per rule, for hash */ | |
270 | return -EINVAL; | |
271 | ||
272 | watch = audit_init_watch(path); | |
273 | if (unlikely(IS_ERR(watch))) | |
274 | return PTR_ERR(watch); | |
275 | ||
276 | audit_get_watch(watch); | |
277 | krule->watch = watch; | |
278 | ||
279 | return 0; | |
280 | } | |
281 | ||
b915543b AV |
282 | static __u32 *classes[AUDIT_SYSCALL_CLASSES]; |
283 | ||
284 | int __init audit_register_class(int class, unsigned *list) | |
285 | { | |
286 | __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL); | |
287 | if (!p) | |
288 | return -ENOMEM; | |
289 | while (*list != ~0U) { | |
290 | unsigned n = *list++; | |
291 | if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { | |
292 | kfree(p); | |
293 | return -EINVAL; | |
294 | } | |
295 | p[AUDIT_WORD(n)] |= AUDIT_BIT(n); | |
296 | } | |
297 | if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { | |
298 | kfree(p); | |
299 | return -EINVAL; | |
300 | } | |
301 | classes[class] = p; | |
302 | return 0; | |
303 | } | |
304 | ||
93315ed6 AG |
305 | /* Common user-space to kernel rule translation. */ |
306 | static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) | |
307 | { | |
308 | unsigned listnr; | |
309 | struct audit_entry *entry; | |
93315ed6 AG |
310 | int i, err; |
311 | ||
312 | err = -EINVAL; | |
313 | listnr = rule->flags & ~AUDIT_FILTER_PREPEND; | |
314 | switch(listnr) { | |
315 | default: | |
316 | goto exit_err; | |
317 | case AUDIT_FILTER_USER: | |
318 | case AUDIT_FILTER_TYPE: | |
319 | #ifdef CONFIG_AUDITSYSCALL | |
320 | case AUDIT_FILTER_ENTRY: | |
321 | case AUDIT_FILTER_EXIT: | |
322 | case AUDIT_FILTER_TASK: | |
323 | #endif | |
324 | ; | |
325 | } | |
014149cc AV |
326 | if (unlikely(rule->action == AUDIT_POSSIBLE)) { |
327 | printk(KERN_ERR "AUDIT_POSSIBLE is deprecated\n"); | |
328 | goto exit_err; | |
329 | } | |
330 | if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS) | |
93315ed6 AG |
331 | goto exit_err; |
332 | if (rule->field_count > AUDIT_MAX_FIELDS) | |
333 | goto exit_err; | |
334 | ||
335 | err = -ENOMEM; | |
3dc7e315 DG |
336 | entry = audit_init_entry(rule->field_count); |
337 | if (!entry) | |
93315ed6 | 338 | goto exit_err; |
93315ed6 AG |
339 | |
340 | entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND; | |
341 | entry->rule.listnr = listnr; | |
342 | entry->rule.action = rule->action; | |
343 | entry->rule.field_count = rule->field_count; | |
93315ed6 AG |
344 | |
345 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
346 | entry->rule.mask[i] = rule->mask[i]; | |
347 | ||
b915543b AV |
348 | for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { |
349 | int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; | |
350 | __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; | |
351 | __u32 *class; | |
352 | ||
353 | if (!(*p & AUDIT_BIT(bit))) | |
354 | continue; | |
355 | *p &= ~AUDIT_BIT(bit); | |
356 | class = classes[i]; | |
357 | if (class) { | |
358 | int j; | |
359 | for (j = 0; j < AUDIT_BITMASK_SIZE; j++) | |
360 | entry->rule.mask[j] |= class[j]; | |
361 | } | |
362 | } | |
363 | ||
93315ed6 AG |
364 | return entry; |
365 | ||
366 | exit_err: | |
367 | return ERR_PTR(err); | |
368 | } | |
369 | ||
370 | /* Translate struct audit_rule to kernel's rule respresentation. | |
371 | * Exists for backward compatibility with userspace. */ | |
372 | static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) | |
373 | { | |
374 | struct audit_entry *entry; | |
f368c07d | 375 | struct audit_field *f; |
93315ed6 | 376 | int err = 0; |
fe7752ba DW |
377 | int i; |
378 | ||
93315ed6 AG |
379 | entry = audit_to_entry_common(rule); |
380 | if (IS_ERR(entry)) | |
381 | goto exit_nofree; | |
382 | ||
383 | for (i = 0; i < rule->field_count; i++) { | |
384 | struct audit_field *f = &entry->rule.fields[i]; | |
385 | ||
93315ed6 AG |
386 | f->op = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS); |
387 | f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS); | |
388 | f->val = rule->values[i]; | |
389 | ||
f368c07d | 390 | err = -EINVAL; |
f368c07d | 391 | switch(f->type) { |
0a73dccc | 392 | default: |
3dc7e315 | 393 | goto exit_free; |
0a73dccc AV |
394 | case AUDIT_PID: |
395 | case AUDIT_UID: | |
396 | case AUDIT_EUID: | |
397 | case AUDIT_SUID: | |
398 | case AUDIT_FSUID: | |
399 | case AUDIT_GID: | |
400 | case AUDIT_EGID: | |
401 | case AUDIT_SGID: | |
402 | case AUDIT_FSGID: | |
403 | case AUDIT_LOGINUID: | |
404 | case AUDIT_PERS: | |
405 | case AUDIT_ARCH: | |
406 | case AUDIT_MSGTYPE: | |
3b33ac31 | 407 | case AUDIT_PPID: |
0a73dccc AV |
408 | case AUDIT_DEVMAJOR: |
409 | case AUDIT_DEVMINOR: | |
410 | case AUDIT_EXIT: | |
411 | case AUDIT_SUCCESS: | |
412 | case AUDIT_ARG0: | |
413 | case AUDIT_ARG1: | |
414 | case AUDIT_ARG2: | |
415 | case AUDIT_ARG3: | |
416 | break; | |
f368c07d AG |
417 | case AUDIT_INODE: |
418 | err = audit_to_inode(&entry->rule, f); | |
419 | if (err) | |
420 | goto exit_free; | |
421 | break; | |
3dc7e315 DG |
422 | } |
423 | ||
93315ed6 | 424 | entry->rule.vers_ops = (f->op & AUDIT_OPERATORS) ? 2 : 1; |
d9d9ec6e DK |
425 | |
426 | /* Support for legacy operators where | |
427 | * AUDIT_NEGATE bit signifies != and otherwise assumes == */ | |
93315ed6 | 428 | if (f->op & AUDIT_NEGATE) |
d9d9ec6e DK |
429 | f->op = AUDIT_NOT_EQUAL; |
430 | else if (!f->op) | |
431 | f->op = AUDIT_EQUAL; | |
432 | else if (f->op == AUDIT_OPERATORS) { | |
433 | err = -EINVAL; | |
434 | goto exit_free; | |
435 | } | |
fe7752ba | 436 | } |
93315ed6 | 437 | |
f368c07d AG |
438 | f = entry->rule.inode_f; |
439 | if (f) { | |
440 | switch(f->op) { | |
441 | case AUDIT_NOT_EQUAL: | |
442 | entry->rule.inode_f = NULL; | |
443 | case AUDIT_EQUAL: | |
444 | break; | |
445 | default: | |
5422e01a | 446 | err = -EINVAL; |
f368c07d AG |
447 | goto exit_free; |
448 | } | |
449 | } | |
450 | ||
93315ed6 AG |
451 | exit_nofree: |
452 | return entry; | |
453 | ||
454 | exit_free: | |
455 | audit_free_rule(entry); | |
456 | return ERR_PTR(err); | |
fe7752ba DW |
457 | } |
458 | ||
93315ed6 AG |
459 | /* Translate struct audit_rule_data to kernel's rule respresentation. */ |
460 | static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, | |
461 | size_t datasz) | |
fe7752ba | 462 | { |
93315ed6 AG |
463 | int err = 0; |
464 | struct audit_entry *entry; | |
f368c07d | 465 | struct audit_field *f; |
93315ed6 | 466 | void *bufp; |
3dc7e315 | 467 | size_t remain = datasz - sizeof(struct audit_rule_data); |
fe7752ba | 468 | int i; |
3dc7e315 | 469 | char *str; |
fe7752ba | 470 | |
93315ed6 AG |
471 | entry = audit_to_entry_common((struct audit_rule *)data); |
472 | if (IS_ERR(entry)) | |
473 | goto exit_nofree; | |
fe7752ba | 474 | |
93315ed6 AG |
475 | bufp = data->buf; |
476 | entry->rule.vers_ops = 2; | |
477 | for (i = 0; i < data->field_count; i++) { | |
478 | struct audit_field *f = &entry->rule.fields[i]; | |
479 | ||
480 | err = -EINVAL; | |
481 | if (!(data->fieldflags[i] & AUDIT_OPERATORS) || | |
482 | data->fieldflags[i] & ~AUDIT_OPERATORS) | |
483 | goto exit_free; | |
484 | ||
485 | f->op = data->fieldflags[i] & AUDIT_OPERATORS; | |
486 | f->type = data->fields[i]; | |
3dc7e315 DG |
487 | f->val = data->values[i]; |
488 | f->se_str = NULL; | |
489 | f->se_rule = NULL; | |
93315ed6 | 490 | switch(f->type) { |
0a73dccc AV |
491 | case AUDIT_PID: |
492 | case AUDIT_UID: | |
493 | case AUDIT_EUID: | |
494 | case AUDIT_SUID: | |
495 | case AUDIT_FSUID: | |
496 | case AUDIT_GID: | |
497 | case AUDIT_EGID: | |
498 | case AUDIT_SGID: | |
499 | case AUDIT_FSGID: | |
500 | case AUDIT_LOGINUID: | |
501 | case AUDIT_PERS: | |
502 | case AUDIT_ARCH: | |
503 | case AUDIT_MSGTYPE: | |
504 | case AUDIT_PPID: | |
505 | case AUDIT_DEVMAJOR: | |
506 | case AUDIT_DEVMINOR: | |
507 | case AUDIT_EXIT: | |
508 | case AUDIT_SUCCESS: | |
509 | case AUDIT_ARG0: | |
510 | case AUDIT_ARG1: | |
511 | case AUDIT_ARG2: | |
512 | case AUDIT_ARG3: | |
513 | break; | |
3a6b9f85 DG |
514 | case AUDIT_SUBJ_USER: |
515 | case AUDIT_SUBJ_ROLE: | |
516 | case AUDIT_SUBJ_TYPE: | |
517 | case AUDIT_SUBJ_SEN: | |
518 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
519 | case AUDIT_OBJ_USER: |
520 | case AUDIT_OBJ_ROLE: | |
521 | case AUDIT_OBJ_TYPE: | |
522 | case AUDIT_OBJ_LEV_LOW: | |
523 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
524 | str = audit_unpack_string(&bufp, &remain, f->val); |
525 | if (IS_ERR(str)) | |
526 | goto exit_free; | |
527 | entry->rule.buflen += f->val; | |
528 | ||
529 | err = selinux_audit_rule_init(f->type, f->op, str, | |
530 | &f->se_rule); | |
531 | /* Keep currently invalid fields around in case they | |
532 | * become valid after a policy reload. */ | |
533 | if (err == -EINVAL) { | |
534 | printk(KERN_WARNING "audit rule for selinux " | |
535 | "\'%s\' is invalid\n", str); | |
536 | err = 0; | |
537 | } | |
538 | if (err) { | |
539 | kfree(str); | |
540 | goto exit_free; | |
541 | } else | |
542 | f->se_str = str; | |
543 | break; | |
f368c07d AG |
544 | case AUDIT_WATCH: |
545 | str = audit_unpack_string(&bufp, &remain, f->val); | |
546 | if (IS_ERR(str)) | |
547 | goto exit_free; | |
548 | entry->rule.buflen += f->val; | |
549 | ||
550 | err = audit_to_watch(&entry->rule, str, f->val, f->op); | |
551 | if (err) { | |
552 | kfree(str); | |
553 | goto exit_free; | |
554 | } | |
555 | break; | |
556 | case AUDIT_INODE: | |
557 | err = audit_to_inode(&entry->rule, f); | |
558 | if (err) | |
559 | goto exit_free; | |
560 | break; | |
5adc8a6a AG |
561 | case AUDIT_FILTERKEY: |
562 | err = -EINVAL; | |
563 | if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN) | |
564 | goto exit_free; | |
565 | str = audit_unpack_string(&bufp, &remain, f->val); | |
566 | if (IS_ERR(str)) | |
567 | goto exit_free; | |
568 | entry->rule.buflen += f->val; | |
569 | entry->rule.filterkey = str; | |
570 | break; | |
0a73dccc AV |
571 | default: |
572 | goto exit_free; | |
f368c07d AG |
573 | } |
574 | } | |
575 | ||
576 | f = entry->rule.inode_f; | |
577 | if (f) { | |
578 | switch(f->op) { | |
579 | case AUDIT_NOT_EQUAL: | |
580 | entry->rule.inode_f = NULL; | |
581 | case AUDIT_EQUAL: | |
582 | break; | |
583 | default: | |
5422e01a | 584 | err = -EINVAL; |
f368c07d | 585 | goto exit_free; |
93315ed6 AG |
586 | } |
587 | } | |
588 | ||
589 | exit_nofree: | |
590 | return entry; | |
591 | ||
592 | exit_free: | |
593 | audit_free_rule(entry); | |
594 | return ERR_PTR(err); | |
595 | } | |
596 | ||
597 | /* Pack a filter field's string representation into data block. */ | |
598 | static inline size_t audit_pack_string(void **bufp, char *str) | |
599 | { | |
600 | size_t len = strlen(str); | |
601 | ||
602 | memcpy(*bufp, str, len); | |
603 | *bufp += len; | |
604 | ||
605 | return len; | |
606 | } | |
607 | ||
608 | /* Translate kernel rule respresentation to struct audit_rule. | |
609 | * Exists for backward compatibility with userspace. */ | |
610 | static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule) | |
611 | { | |
612 | struct audit_rule *rule; | |
613 | int i; | |
614 | ||
615 | rule = kmalloc(sizeof(*rule), GFP_KERNEL); | |
616 | if (unlikely(!rule)) | |
0a3b483e | 617 | return NULL; |
93315ed6 AG |
618 | memset(rule, 0, sizeof(*rule)); |
619 | ||
620 | rule->flags = krule->flags | krule->listnr; | |
621 | rule->action = krule->action; | |
622 | rule->field_count = krule->field_count; | |
623 | for (i = 0; i < rule->field_count; i++) { | |
624 | rule->values[i] = krule->fields[i].val; | |
625 | rule->fields[i] = krule->fields[i].type; | |
626 | ||
627 | if (krule->vers_ops == 1) { | |
628 | if (krule->fields[i].op & AUDIT_NOT_EQUAL) | |
629 | rule->fields[i] |= AUDIT_NEGATE; | |
630 | } else { | |
631 | rule->fields[i] |= krule->fields[i].op; | |
632 | } | |
633 | } | |
634 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i]; | |
635 | ||
636 | return rule; | |
637 | } | |
fe7752ba | 638 | |
93315ed6 AG |
639 | /* Translate kernel rule respresentation to struct audit_rule_data. */ |
640 | static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) | |
641 | { | |
642 | struct audit_rule_data *data; | |
643 | void *bufp; | |
644 | int i; | |
645 | ||
646 | data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); | |
647 | if (unlikely(!data)) | |
0a3b483e | 648 | return NULL; |
93315ed6 AG |
649 | memset(data, 0, sizeof(*data)); |
650 | ||
651 | data->flags = krule->flags | krule->listnr; | |
652 | data->action = krule->action; | |
653 | data->field_count = krule->field_count; | |
654 | bufp = data->buf; | |
655 | for (i = 0; i < data->field_count; i++) { | |
656 | struct audit_field *f = &krule->fields[i]; | |
657 | ||
658 | data->fields[i] = f->type; | |
659 | data->fieldflags[i] = f->op; | |
660 | switch(f->type) { | |
3a6b9f85 DG |
661 | case AUDIT_SUBJ_USER: |
662 | case AUDIT_SUBJ_ROLE: | |
663 | case AUDIT_SUBJ_TYPE: | |
664 | case AUDIT_SUBJ_SEN: | |
665 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
666 | case AUDIT_OBJ_USER: |
667 | case AUDIT_OBJ_ROLE: | |
668 | case AUDIT_OBJ_TYPE: | |
669 | case AUDIT_OBJ_LEV_LOW: | |
670 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
671 | data->buflen += data->values[i] = |
672 | audit_pack_string(&bufp, f->se_str); | |
673 | break; | |
f368c07d AG |
674 | case AUDIT_WATCH: |
675 | data->buflen += data->values[i] = | |
676 | audit_pack_string(&bufp, krule->watch->path); | |
677 | break; | |
5adc8a6a AG |
678 | case AUDIT_FILTERKEY: |
679 | data->buflen += data->values[i] = | |
680 | audit_pack_string(&bufp, krule->filterkey); | |
681 | break; | |
93315ed6 AG |
682 | default: |
683 | data->values[i] = f->val; | |
684 | } | |
685 | } | |
686 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i]; | |
687 | ||
688 | return data; | |
689 | } | |
690 | ||
691 | /* Compare two rules in kernel format. Considered success if rules | |
692 | * don't match. */ | |
693 | static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) | |
694 | { | |
695 | int i; | |
696 | ||
697 | if (a->flags != b->flags || | |
698 | a->listnr != b->listnr || | |
699 | a->action != b->action || | |
700 | a->field_count != b->field_count) | |
fe7752ba DW |
701 | return 1; |
702 | ||
703 | for (i = 0; i < a->field_count; i++) { | |
93315ed6 AG |
704 | if (a->fields[i].type != b->fields[i].type || |
705 | a->fields[i].op != b->fields[i].op) | |
fe7752ba | 706 | return 1; |
93315ed6 AG |
707 | |
708 | switch(a->fields[i].type) { | |
3a6b9f85 DG |
709 | case AUDIT_SUBJ_USER: |
710 | case AUDIT_SUBJ_ROLE: | |
711 | case AUDIT_SUBJ_TYPE: | |
712 | case AUDIT_SUBJ_SEN: | |
713 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
714 | case AUDIT_OBJ_USER: |
715 | case AUDIT_OBJ_ROLE: | |
716 | case AUDIT_OBJ_TYPE: | |
717 | case AUDIT_OBJ_LEV_LOW: | |
718 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
719 | if (strcmp(a->fields[i].se_str, b->fields[i].se_str)) |
720 | return 1; | |
721 | break; | |
f368c07d AG |
722 | case AUDIT_WATCH: |
723 | if (strcmp(a->watch->path, b->watch->path)) | |
724 | return 1; | |
725 | break; | |
5adc8a6a AG |
726 | case AUDIT_FILTERKEY: |
727 | /* both filterkeys exist based on above type compare */ | |
728 | if (strcmp(a->filterkey, b->filterkey)) | |
729 | return 1; | |
730 | break; | |
93315ed6 AG |
731 | default: |
732 | if (a->fields[i].val != b->fields[i].val) | |
733 | return 1; | |
734 | } | |
fe7752ba DW |
735 | } |
736 | ||
737 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
738 | if (a->mask[i] != b->mask[i]) | |
739 | return 1; | |
740 | ||
741 | return 0; | |
742 | } | |
743 | ||
f368c07d AG |
744 | /* Duplicate the given audit watch. The new watch's rules list is initialized |
745 | * to an empty list and wlist is undefined. */ | |
746 | static struct audit_watch *audit_dupe_watch(struct audit_watch *old) | |
747 | { | |
748 | char *path; | |
749 | struct audit_watch *new; | |
750 | ||
751 | path = kstrdup(old->path, GFP_KERNEL); | |
752 | if (unlikely(!path)) | |
753 | return ERR_PTR(-ENOMEM); | |
754 | ||
755 | new = audit_init_watch(path); | |
756 | if (unlikely(IS_ERR(new))) { | |
757 | kfree(path); | |
758 | goto out; | |
759 | } | |
760 | ||
761 | new->dev = old->dev; | |
762 | new->ino = old->ino; | |
763 | get_inotify_watch(&old->parent->wdata); | |
764 | new->parent = old->parent; | |
765 | ||
766 | out: | |
767 | return new; | |
768 | } | |
769 | ||
3dc7e315 DG |
770 | /* Duplicate selinux field information. The se_rule is opaque, so must be |
771 | * re-initialized. */ | |
772 | static inline int audit_dupe_selinux_field(struct audit_field *df, | |
773 | struct audit_field *sf) | |
774 | { | |
775 | int ret = 0; | |
776 | char *se_str; | |
777 | ||
778 | /* our own copy of se_str */ | |
779 | se_str = kstrdup(sf->se_str, GFP_KERNEL); | |
780 | if (unlikely(IS_ERR(se_str))) | |
781 | return -ENOMEM; | |
782 | df->se_str = se_str; | |
783 | ||
784 | /* our own (refreshed) copy of se_rule */ | |
785 | ret = selinux_audit_rule_init(df->type, df->op, df->se_str, | |
786 | &df->se_rule); | |
787 | /* Keep currently invalid fields around in case they | |
788 | * become valid after a policy reload. */ | |
789 | if (ret == -EINVAL) { | |
790 | printk(KERN_WARNING "audit rule for selinux \'%s\' is " | |
791 | "invalid\n", df->se_str); | |
792 | ret = 0; | |
793 | } | |
794 | ||
795 | return ret; | |
796 | } | |
797 | ||
798 | /* Duplicate an audit rule. This will be a deep copy with the exception | |
799 | * of the watch - that pointer is carried over. The selinux specific fields | |
800 | * will be updated in the copy. The point is to be able to replace the old | |
f368c07d AG |
801 | * rule with the new rule in the filterlist, then free the old rule. |
802 | * The rlist element is undefined; list manipulations are handled apart from | |
803 | * the initial copy. */ | |
804 | static struct audit_entry *audit_dupe_rule(struct audit_krule *old, | |
805 | struct audit_watch *watch) | |
3dc7e315 DG |
806 | { |
807 | u32 fcount = old->field_count; | |
808 | struct audit_entry *entry; | |
809 | struct audit_krule *new; | |
5adc8a6a | 810 | char *fk; |
3dc7e315 DG |
811 | int i, err = 0; |
812 | ||
813 | entry = audit_init_entry(fcount); | |
814 | if (unlikely(!entry)) | |
815 | return ERR_PTR(-ENOMEM); | |
816 | ||
817 | new = &entry->rule; | |
818 | new->vers_ops = old->vers_ops; | |
819 | new->flags = old->flags; | |
820 | new->listnr = old->listnr; | |
821 | new->action = old->action; | |
822 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
823 | new->mask[i] = old->mask[i]; | |
824 | new->buflen = old->buflen; | |
f368c07d AG |
825 | new->inode_f = old->inode_f; |
826 | new->watch = NULL; | |
3dc7e315 DG |
827 | new->field_count = old->field_count; |
828 | memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount); | |
829 | ||
830 | /* deep copy this information, updating the se_rule fields, because | |
831 | * the originals will all be freed when the old rule is freed. */ | |
832 | for (i = 0; i < fcount; i++) { | |
833 | switch (new->fields[i].type) { | |
3a6b9f85 DG |
834 | case AUDIT_SUBJ_USER: |
835 | case AUDIT_SUBJ_ROLE: | |
836 | case AUDIT_SUBJ_TYPE: | |
837 | case AUDIT_SUBJ_SEN: | |
838 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
839 | case AUDIT_OBJ_USER: |
840 | case AUDIT_OBJ_ROLE: | |
841 | case AUDIT_OBJ_TYPE: | |
842 | case AUDIT_OBJ_LEV_LOW: | |
843 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
844 | err = audit_dupe_selinux_field(&new->fields[i], |
845 | &old->fields[i]); | |
5adc8a6a AG |
846 | break; |
847 | case AUDIT_FILTERKEY: | |
848 | fk = kstrdup(old->filterkey, GFP_KERNEL); | |
849 | if (unlikely(!fk)) | |
850 | err = -ENOMEM; | |
851 | else | |
852 | new->filterkey = fk; | |
3dc7e315 DG |
853 | } |
854 | if (err) { | |
855 | audit_free_rule(entry); | |
856 | return ERR_PTR(err); | |
857 | } | |
858 | } | |
859 | ||
f368c07d AG |
860 | if (watch) { |
861 | audit_get_watch(watch); | |
862 | new->watch = watch; | |
863 | } | |
864 | ||
3dc7e315 DG |
865 | return entry; |
866 | } | |
867 | ||
f368c07d AG |
868 | /* Update inode info in audit rules based on filesystem event. */ |
869 | static void audit_update_watch(struct audit_parent *parent, | |
870 | const char *dname, dev_t dev, | |
871 | unsigned long ino, unsigned invalidating) | |
872 | { | |
873 | struct audit_watch *owatch, *nwatch, *nextw; | |
874 | struct audit_krule *r, *nextr; | |
875 | struct audit_entry *oentry, *nentry; | |
876 | struct audit_buffer *ab; | |
877 | ||
878 | mutex_lock(&audit_filter_mutex); | |
879 | list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) { | |
9c937dcc | 880 | if (audit_compare_dname_path(dname, owatch->path, NULL)) |
f368c07d AG |
881 | continue; |
882 | ||
883 | /* If the update involves invalidating rules, do the inode-based | |
884 | * filtering now, so we don't omit records. */ | |
885 | if (invalidating && | |
886 | audit_filter_inodes(current, current->audit_context) == AUDIT_RECORD_CONTEXT) | |
887 | audit_set_auditable(current->audit_context); | |
888 | ||
889 | nwatch = audit_dupe_watch(owatch); | |
890 | if (unlikely(IS_ERR(nwatch))) { | |
891 | mutex_unlock(&audit_filter_mutex); | |
892 | audit_panic("error updating watch, skipping"); | |
893 | return; | |
894 | } | |
895 | nwatch->dev = dev; | |
896 | nwatch->ino = ino; | |
897 | ||
898 | list_for_each_entry_safe(r, nextr, &owatch->rules, rlist) { | |
899 | ||
900 | oentry = container_of(r, struct audit_entry, rule); | |
901 | list_del(&oentry->rule.rlist); | |
902 | list_del_rcu(&oentry->list); | |
903 | ||
904 | nentry = audit_dupe_rule(&oentry->rule, nwatch); | |
905 | if (unlikely(IS_ERR(nentry))) | |
906 | audit_panic("error updating watch, removing"); | |
907 | else { | |
908 | int h = audit_hash_ino((u32)ino); | |
909 | list_add(&nentry->rule.rlist, &nwatch->rules); | |
910 | list_add_rcu(&nentry->list, &audit_inode_hash[h]); | |
911 | } | |
912 | ||
913 | call_rcu(&oentry->rcu, audit_free_rule_rcu); | |
914 | } | |
915 | ||
916 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); | |
5974501e | 917 | audit_log_format(ab, "audit updated rules specifying path="); |
f368c07d AG |
918 | audit_log_untrustedstring(ab, owatch->path); |
919 | audit_log_format(ab, " with dev=%u ino=%lu\n", dev, ino); | |
920 | audit_log_end(ab); | |
921 | ||
922 | audit_remove_watch(owatch); | |
923 | goto add_watch_to_parent; /* event applies to a single watch */ | |
924 | } | |
925 | mutex_unlock(&audit_filter_mutex); | |
926 | return; | |
927 | ||
928 | add_watch_to_parent: | |
929 | list_add(&nwatch->wlist, &parent->watches); | |
930 | mutex_unlock(&audit_filter_mutex); | |
931 | return; | |
932 | } | |
933 | ||
934 | /* Remove all watches & rules associated with a parent that is going away. */ | |
935 | static void audit_remove_parent_watches(struct audit_parent *parent) | |
936 | { | |
937 | struct audit_watch *w, *nextw; | |
938 | struct audit_krule *r, *nextr; | |
939 | struct audit_entry *e; | |
5974501e | 940 | struct audit_buffer *ab; |
f368c07d AG |
941 | |
942 | mutex_lock(&audit_filter_mutex); | |
943 | parent->flags |= AUDIT_PARENT_INVALID; | |
944 | list_for_each_entry_safe(w, nextw, &parent->watches, wlist) { | |
945 | list_for_each_entry_safe(r, nextr, &w->rules, rlist) { | |
946 | e = container_of(r, struct audit_entry, rule); | |
5974501e AG |
947 | |
948 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); | |
949 | audit_log_format(ab, "audit implicitly removed rule path="); | |
950 | audit_log_untrustedstring(ab, w->path); | |
951 | if (r->filterkey) { | |
952 | audit_log_format(ab, " key="); | |
953 | audit_log_untrustedstring(ab, r->filterkey); | |
954 | } else | |
955 | audit_log_format(ab, " key=(null)"); | |
956 | audit_log_format(ab, " list=%d", r->listnr); | |
957 | audit_log_end(ab); | |
958 | ||
f368c07d AG |
959 | list_del(&r->rlist); |
960 | list_del_rcu(&e->list); | |
961 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
f368c07d AG |
962 | } |
963 | audit_remove_watch(w); | |
964 | } | |
965 | mutex_unlock(&audit_filter_mutex); | |
966 | } | |
967 | ||
968 | /* Unregister inotify watches for parents on in_list. | |
969 | * Generates an IN_IGNORED event. */ | |
970 | static void audit_inotify_unregister(struct list_head *in_list) | |
971 | { | |
972 | struct audit_parent *p, *n; | |
973 | ||
974 | list_for_each_entry_safe(p, n, in_list, ilist) { | |
975 | list_del(&p->ilist); | |
976 | inotify_rm_watch(audit_ih, &p->wdata); | |
977 | /* the put matching the get in audit_do_del_rule() */ | |
978 | put_inotify_watch(&p->wdata); | |
979 | } | |
980 | } | |
981 | ||
982 | /* Find an existing audit rule. | |
983 | * Caller must hold audit_filter_mutex to prevent stale rule data. */ | |
984 | static struct audit_entry *audit_find_rule(struct audit_entry *entry, | |
985 | struct list_head *list) | |
986 | { | |
987 | struct audit_entry *e, *found = NULL; | |
988 | int h; | |
989 | ||
990 | if (entry->rule.watch) { | |
991 | /* we don't know the inode number, so must walk entire hash */ | |
992 | for (h = 0; h < AUDIT_INODE_BUCKETS; h++) { | |
993 | list = &audit_inode_hash[h]; | |
994 | list_for_each_entry(e, list, list) | |
995 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
996 | found = e; | |
997 | goto out; | |
998 | } | |
999 | } | |
1000 | goto out; | |
1001 | } | |
1002 | ||
1003 | list_for_each_entry(e, list, list) | |
1004 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
1005 | found = e; | |
1006 | goto out; | |
1007 | } | |
1008 | ||
1009 | out: | |
1010 | return found; | |
1011 | } | |
1012 | ||
1013 | /* Get path information necessary for adding watches. */ | |
1014 | static int audit_get_nd(char *path, struct nameidata **ndp, | |
1015 | struct nameidata **ndw) | |
1016 | { | |
1017 | struct nameidata *ndparent, *ndwatch; | |
1018 | int err; | |
1019 | ||
1020 | ndparent = kmalloc(sizeof(*ndparent), GFP_KERNEL); | |
1021 | if (unlikely(!ndparent)) | |
1022 | return -ENOMEM; | |
1023 | ||
1024 | ndwatch = kmalloc(sizeof(*ndwatch), GFP_KERNEL); | |
1025 | if (unlikely(!ndwatch)) { | |
1026 | kfree(ndparent); | |
1027 | return -ENOMEM; | |
1028 | } | |
1029 | ||
1030 | err = path_lookup(path, LOOKUP_PARENT, ndparent); | |
1031 | if (err) { | |
1032 | kfree(ndparent); | |
1033 | kfree(ndwatch); | |
1034 | return err; | |
1035 | } | |
1036 | ||
1037 | err = path_lookup(path, 0, ndwatch); | |
1038 | if (err) { | |
1039 | kfree(ndwatch); | |
1040 | ndwatch = NULL; | |
1041 | } | |
1042 | ||
1043 | *ndp = ndparent; | |
1044 | *ndw = ndwatch; | |
1045 | ||
1046 | return 0; | |
1047 | } | |
1048 | ||
1049 | /* Release resources used for watch path information. */ | |
1050 | static void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw) | |
1051 | { | |
1052 | if (ndp) { | |
1053 | path_release(ndp); | |
1054 | kfree(ndp); | |
1055 | } | |
1056 | if (ndw) { | |
1057 | path_release(ndw); | |
1058 | kfree(ndw); | |
1059 | } | |
1060 | } | |
1061 | ||
1062 | /* Associate the given rule with an existing parent inotify_watch. | |
1063 | * Caller must hold audit_filter_mutex. */ | |
1064 | static void audit_add_to_parent(struct audit_krule *krule, | |
1065 | struct audit_parent *parent) | |
1066 | { | |
1067 | struct audit_watch *w, *watch = krule->watch; | |
1068 | int watch_found = 0; | |
1069 | ||
1070 | list_for_each_entry(w, &parent->watches, wlist) { | |
1071 | if (strcmp(watch->path, w->path)) | |
1072 | continue; | |
1073 | ||
1074 | watch_found = 1; | |
1075 | ||
1076 | /* put krule's and initial refs to temporary watch */ | |
1077 | audit_put_watch(watch); | |
1078 | audit_put_watch(watch); | |
1079 | ||
1080 | audit_get_watch(w); | |
1081 | krule->watch = watch = w; | |
1082 | break; | |
1083 | } | |
1084 | ||
1085 | if (!watch_found) { | |
1086 | get_inotify_watch(&parent->wdata); | |
1087 | watch->parent = parent; | |
1088 | ||
1089 | list_add(&watch->wlist, &parent->watches); | |
1090 | } | |
1091 | list_add(&krule->rlist, &watch->rules); | |
1092 | } | |
1093 | ||
1094 | /* Find a matching watch entry, or add this one. | |
1095 | * Caller must hold audit_filter_mutex. */ | |
1096 | static int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, | |
1097 | struct nameidata *ndw) | |
1098 | { | |
1099 | struct audit_watch *watch = krule->watch; | |
1100 | struct inotify_watch *i_watch; | |
1101 | struct audit_parent *parent; | |
1102 | int ret = 0; | |
1103 | ||
1104 | /* update watch filter fields */ | |
1105 | if (ndw) { | |
1106 | watch->dev = ndw->dentry->d_inode->i_sb->s_dev; | |
1107 | watch->ino = ndw->dentry->d_inode->i_ino; | |
1108 | } | |
1109 | ||
1110 | /* The audit_filter_mutex must not be held during inotify calls because | |
1111 | * we hold it during inotify event callback processing. If an existing | |
1112 | * inotify watch is found, inotify_find_watch() grabs a reference before | |
1113 | * returning. | |
1114 | */ | |
1115 | mutex_unlock(&audit_filter_mutex); | |
1116 | ||
1117 | if (inotify_find_watch(audit_ih, ndp->dentry->d_inode, &i_watch) < 0) { | |
1118 | parent = audit_init_parent(ndp); | |
1119 | if (IS_ERR(parent)) { | |
1120 | /* caller expects mutex locked */ | |
1121 | mutex_lock(&audit_filter_mutex); | |
1122 | return PTR_ERR(parent); | |
1123 | } | |
1124 | } else | |
1125 | parent = container_of(i_watch, struct audit_parent, wdata); | |
1126 | ||
1127 | mutex_lock(&audit_filter_mutex); | |
1128 | ||
1129 | /* parent was moved before we took audit_filter_mutex */ | |
1130 | if (parent->flags & AUDIT_PARENT_INVALID) | |
1131 | ret = -ENOENT; | |
1132 | else | |
1133 | audit_add_to_parent(krule, parent); | |
1134 | ||
1135 | /* match get in audit_init_parent or inotify_find_watch */ | |
1136 | put_inotify_watch(&parent->wdata); | |
1137 | return ret; | |
1138 | } | |
1139 | ||
1140 | /* Add rule to given filterlist if not a duplicate. */ | |
93315ed6 | 1141 | static inline int audit_add_rule(struct audit_entry *entry, |
f368c07d | 1142 | struct list_head *list) |
fe7752ba | 1143 | { |
93315ed6 | 1144 | struct audit_entry *e; |
f368c07d AG |
1145 | struct audit_field *inode_f = entry->rule.inode_f; |
1146 | struct audit_watch *watch = entry->rule.watch; | |
1147 | struct nameidata *ndp, *ndw; | |
1148 | int h, err, putnd_needed = 0; | |
471a5c7c AV |
1149 | #ifdef CONFIG_AUDITSYSCALL |
1150 | int dont_count = 0; | |
1151 | ||
1152 | /* If either of these, don't count towards total */ | |
1153 | if (entry->rule.listnr == AUDIT_FILTER_USER || | |
1154 | entry->rule.listnr == AUDIT_FILTER_TYPE) | |
1155 | dont_count = 1; | |
1156 | #endif | |
f368c07d AG |
1157 | |
1158 | if (inode_f) { | |
1159 | h = audit_hash_ino(inode_f->val); | |
1160 | list = &audit_inode_hash[h]; | |
1161 | } | |
1162 | ||
1163 | mutex_lock(&audit_filter_mutex); | |
1164 | e = audit_find_rule(entry, list); | |
1165 | mutex_unlock(&audit_filter_mutex); | |
1166 | if (e) { | |
1167 | err = -EEXIST; | |
1168 | goto error; | |
1169 | } | |
fe7752ba | 1170 | |
f368c07d AG |
1171 | /* Avoid calling path_lookup under audit_filter_mutex. */ |
1172 | if (watch) { | |
1173 | err = audit_get_nd(watch->path, &ndp, &ndw); | |
1174 | if (err) | |
1175 | goto error; | |
1176 | putnd_needed = 1; | |
1177 | } | |
1178 | ||
1179 | mutex_lock(&audit_filter_mutex); | |
1180 | if (watch) { | |
1181 | /* audit_filter_mutex is dropped and re-taken during this call */ | |
1182 | err = audit_add_watch(&entry->rule, ndp, ndw); | |
1183 | if (err) { | |
1184 | mutex_unlock(&audit_filter_mutex); | |
1185 | goto error; | |
1186 | } | |
1187 | h = audit_hash_ino((u32)watch->ino); | |
1188 | list = &audit_inode_hash[h]; | |
fe7752ba DW |
1189 | } |
1190 | ||
fe7752ba | 1191 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
fe7752ba | 1192 | list_add_rcu(&entry->list, list); |
6a2bceec | 1193 | entry->rule.flags &= ~AUDIT_FILTER_PREPEND; |
fe7752ba DW |
1194 | } else { |
1195 | list_add_tail_rcu(&entry->list, list); | |
1196 | } | |
471a5c7c AV |
1197 | #ifdef CONFIG_AUDITSYSCALL |
1198 | if (!dont_count) | |
1199 | audit_n_rules++; | |
1200 | #endif | |
f368c07d | 1201 | mutex_unlock(&audit_filter_mutex); |
fe7752ba | 1202 | |
f368c07d AG |
1203 | if (putnd_needed) |
1204 | audit_put_nd(ndp, ndw); | |
1205 | ||
1206 | return 0; | |
1207 | ||
1208 | error: | |
1209 | if (putnd_needed) | |
1210 | audit_put_nd(ndp, ndw); | |
1211 | if (watch) | |
1212 | audit_put_watch(watch); /* tmp watch, matches initial get */ | |
1213 | return err; | |
fe7752ba DW |
1214 | } |
1215 | ||
f368c07d | 1216 | /* Remove an existing rule from filterlist. */ |
93315ed6 | 1217 | static inline int audit_del_rule(struct audit_entry *entry, |
fe7752ba DW |
1218 | struct list_head *list) |
1219 | { | |
1220 | struct audit_entry *e; | |
f368c07d AG |
1221 | struct audit_field *inode_f = entry->rule.inode_f; |
1222 | struct audit_watch *watch, *tmp_watch = entry->rule.watch; | |
1223 | LIST_HEAD(inotify_list); | |
1224 | int h, ret = 0; | |
471a5c7c AV |
1225 | #ifdef CONFIG_AUDITSYSCALL |
1226 | int dont_count = 0; | |
1227 | ||
1228 | /* If either of these, don't count towards total */ | |
1229 | if (entry->rule.listnr == AUDIT_FILTER_USER || | |
1230 | entry->rule.listnr == AUDIT_FILTER_TYPE) | |
1231 | dont_count = 1; | |
1232 | #endif | |
f368c07d AG |
1233 | |
1234 | if (inode_f) { | |
1235 | h = audit_hash_ino(inode_f->val); | |
1236 | list = &audit_inode_hash[h]; | |
1237 | } | |
fe7752ba | 1238 | |
f368c07d AG |
1239 | mutex_lock(&audit_filter_mutex); |
1240 | e = audit_find_rule(entry, list); | |
1241 | if (!e) { | |
1242 | mutex_unlock(&audit_filter_mutex); | |
1243 | ret = -ENOENT; | |
1244 | goto out; | |
1245 | } | |
1246 | ||
1247 | watch = e->rule.watch; | |
1248 | if (watch) { | |
1249 | struct audit_parent *parent = watch->parent; | |
1250 | ||
1251 | list_del(&e->rule.rlist); | |
1252 | ||
1253 | if (list_empty(&watch->rules)) { | |
1254 | audit_remove_watch(watch); | |
1255 | ||
1256 | if (list_empty(&parent->watches)) { | |
1257 | /* Put parent on the inotify un-registration | |
1258 | * list. Grab a reference before releasing | |
1259 | * audit_filter_mutex, to be released in | |
1260 | * audit_inotify_unregister(). */ | |
1261 | list_add(&parent->ilist, &inotify_list); | |
1262 | get_inotify_watch(&parent->wdata); | |
1263 | } | |
fe7752ba DW |
1264 | } |
1265 | } | |
f368c07d AG |
1266 | |
1267 | list_del_rcu(&e->list); | |
1268 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
1269 | ||
471a5c7c AV |
1270 | #ifdef CONFIG_AUDITSYSCALL |
1271 | if (!dont_count) | |
1272 | audit_n_rules--; | |
1273 | #endif | |
f368c07d AG |
1274 | mutex_unlock(&audit_filter_mutex); |
1275 | ||
1276 | if (!list_empty(&inotify_list)) | |
1277 | audit_inotify_unregister(&inotify_list); | |
1278 | ||
1279 | out: | |
1280 | if (tmp_watch) | |
1281 | audit_put_watch(tmp_watch); /* match initial get */ | |
1282 | ||
1283 | return ret; | |
fe7752ba DW |
1284 | } |
1285 | ||
93315ed6 AG |
1286 | /* List rules using struct audit_rule. Exists for backward |
1287 | * compatibility with userspace. */ | |
9044e6bc | 1288 | static void audit_list(int pid, int seq, struct sk_buff_head *q) |
fe7752ba | 1289 | { |
9044e6bc | 1290 | struct sk_buff *skb; |
fe7752ba DW |
1291 | struct audit_entry *entry; |
1292 | int i; | |
1293 | ||
f368c07d AG |
1294 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1295 | * iterator to sync with list writers. */ | |
fe7752ba | 1296 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
93315ed6 AG |
1297 | list_for_each_entry(entry, &audit_filter_list[i], list) { |
1298 | struct audit_rule *rule; | |
1299 | ||
1300 | rule = audit_krule_to_rule(&entry->rule); | |
1301 | if (unlikely(!rule)) | |
1302 | break; | |
9044e6bc | 1303 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, |
93315ed6 | 1304 | rule, sizeof(*rule)); |
9044e6bc AV |
1305 | if (skb) |
1306 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1307 | kfree(rule); |
1308 | } | |
fe7752ba | 1309 | } |
f368c07d AG |
1310 | for (i = 0; i < AUDIT_INODE_BUCKETS; i++) { |
1311 | list_for_each_entry(entry, &audit_inode_hash[i], list) { | |
1312 | struct audit_rule *rule; | |
1313 | ||
1314 | rule = audit_krule_to_rule(&entry->rule); | |
1315 | if (unlikely(!rule)) | |
1316 | break; | |
1317 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, | |
1318 | rule, sizeof(*rule)); | |
1319 | if (skb) | |
1320 | skb_queue_tail(q, skb); | |
1321 | kfree(rule); | |
1322 | } | |
1323 | } | |
9044e6bc AV |
1324 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0); |
1325 | if (skb) | |
1326 | skb_queue_tail(q, skb); | |
fe7752ba DW |
1327 | } |
1328 | ||
93315ed6 | 1329 | /* List rules using struct audit_rule_data. */ |
9044e6bc | 1330 | static void audit_list_rules(int pid, int seq, struct sk_buff_head *q) |
93315ed6 | 1331 | { |
9044e6bc | 1332 | struct sk_buff *skb; |
93315ed6 AG |
1333 | struct audit_entry *e; |
1334 | int i; | |
1335 | ||
f368c07d AG |
1336 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1337 | * iterator to sync with list writers. */ | |
93315ed6 AG |
1338 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
1339 | list_for_each_entry(e, &audit_filter_list[i], list) { | |
1340 | struct audit_rule_data *data; | |
1341 | ||
1342 | data = audit_krule_to_data(&e->rule); | |
1343 | if (unlikely(!data)) | |
1344 | break; | |
9044e6bc | 1345 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, |
f368c07d AG |
1346 | data, sizeof(*data) + data->buflen); |
1347 | if (skb) | |
1348 | skb_queue_tail(q, skb); | |
1349 | kfree(data); | |
1350 | } | |
1351 | } | |
1352 | for (i=0; i< AUDIT_INODE_BUCKETS; i++) { | |
1353 | list_for_each_entry(e, &audit_inode_hash[i], list) { | |
1354 | struct audit_rule_data *data; | |
1355 | ||
1356 | data = audit_krule_to_data(&e->rule); | |
1357 | if (unlikely(!data)) | |
1358 | break; | |
1359 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, | |
1360 | data, sizeof(*data) + data->buflen); | |
9044e6bc AV |
1361 | if (skb) |
1362 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1363 | kfree(data); |
1364 | } | |
1365 | } | |
9044e6bc AV |
1366 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); |
1367 | if (skb) | |
1368 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1369 | } |
1370 | ||
5adc8a6a AG |
1371 | /* Log rule additions and removals */ |
1372 | static void audit_log_rule_change(uid_t loginuid, u32 sid, char *action, | |
1373 | struct audit_krule *rule, int res) | |
1374 | { | |
1375 | struct audit_buffer *ab; | |
1376 | ||
1377 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); | |
1378 | if (!ab) | |
1379 | return; | |
1380 | audit_log_format(ab, "auid=%u", loginuid); | |
1381 | if (sid) { | |
1382 | char *ctx = NULL; | |
1383 | u32 len; | |
1384 | if (selinux_ctxid_to_string(sid, &ctx, &len)) | |
1385 | audit_log_format(ab, " ssid=%u", sid); | |
1386 | else | |
1387 | audit_log_format(ab, " subj=%s", ctx); | |
1388 | kfree(ctx); | |
1389 | } | |
1390 | audit_log_format(ab, " %s rule key=", action); | |
1391 | if (rule->filterkey) | |
1392 | audit_log_untrustedstring(ab, rule->filterkey); | |
1393 | else | |
1394 | audit_log_format(ab, "(null)"); | |
1395 | audit_log_format(ab, " list=%d res=%d", rule->listnr, res); | |
1396 | audit_log_end(ab); | |
1397 | } | |
1398 | ||
fe7752ba DW |
1399 | /** |
1400 | * audit_receive_filter - apply all rules to the specified message type | |
1401 | * @type: audit message type | |
1402 | * @pid: target pid for netlink audit messages | |
1403 | * @uid: target uid for netlink audit messages | |
1404 | * @seq: netlink audit message sequence (serial) number | |
1405 | * @data: payload data | |
93315ed6 | 1406 | * @datasz: size of payload data |
fe7752ba | 1407 | * @loginuid: loginuid of sender |
ce29b682 | 1408 | * @sid: SE Linux Security ID of sender |
fe7752ba DW |
1409 | */ |
1410 | int audit_receive_filter(int type, int pid, int uid, int seq, void *data, | |
ce29b682 | 1411 | size_t datasz, uid_t loginuid, u32 sid) |
fe7752ba DW |
1412 | { |
1413 | struct task_struct *tsk; | |
9044e6bc | 1414 | struct audit_netlink_list *dest; |
93315ed6 AG |
1415 | int err = 0; |
1416 | struct audit_entry *entry; | |
fe7752ba DW |
1417 | |
1418 | switch (type) { | |
1419 | case AUDIT_LIST: | |
93315ed6 | 1420 | case AUDIT_LIST_RULES: |
fe7752ba DW |
1421 | /* We can't just spew out the rules here because we might fill |
1422 | * the available socket buffer space and deadlock waiting for | |
1423 | * auditctl to read from it... which isn't ever going to | |
1424 | * happen if we're actually running in the context of auditctl | |
1425 | * trying to _send_ the stuff */ | |
1426 | ||
9044e6bc | 1427 | dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); |
fe7752ba DW |
1428 | if (!dest) |
1429 | return -ENOMEM; | |
9044e6bc AV |
1430 | dest->pid = pid; |
1431 | skb_queue_head_init(&dest->q); | |
fe7752ba | 1432 | |
f368c07d | 1433 | mutex_lock(&audit_filter_mutex); |
93315ed6 | 1434 | if (type == AUDIT_LIST) |
9044e6bc | 1435 | audit_list(pid, seq, &dest->q); |
93315ed6 | 1436 | else |
9044e6bc | 1437 | audit_list_rules(pid, seq, &dest->q); |
f368c07d | 1438 | mutex_unlock(&audit_filter_mutex); |
9044e6bc AV |
1439 | |
1440 | tsk = kthread_run(audit_send_list, dest, "audit_send_list"); | |
fe7752ba | 1441 | if (IS_ERR(tsk)) { |
9044e6bc | 1442 | skb_queue_purge(&dest->q); |
fe7752ba DW |
1443 | kfree(dest); |
1444 | err = PTR_ERR(tsk); | |
1445 | } | |
1446 | break; | |
1447 | case AUDIT_ADD: | |
93315ed6 AG |
1448 | case AUDIT_ADD_RULE: |
1449 | if (type == AUDIT_ADD) | |
1450 | entry = audit_rule_to_entry(data); | |
1451 | else | |
1452 | entry = audit_data_to_entry(data, datasz); | |
1453 | if (IS_ERR(entry)) | |
1454 | return PTR_ERR(entry); | |
1455 | ||
1456 | err = audit_add_rule(entry, | |
1457 | &audit_filter_list[entry->rule.listnr]); | |
5adc8a6a | 1458 | audit_log_rule_change(loginuid, sid, "add", &entry->rule, !err); |
5d330108 AV |
1459 | |
1460 | if (err) | |
93315ed6 | 1461 | audit_free_rule(entry); |
fe7752ba DW |
1462 | break; |
1463 | case AUDIT_DEL: | |
93315ed6 AG |
1464 | case AUDIT_DEL_RULE: |
1465 | if (type == AUDIT_DEL) | |
1466 | entry = audit_rule_to_entry(data); | |
1467 | else | |
1468 | entry = audit_data_to_entry(data, datasz); | |
1469 | if (IS_ERR(entry)) | |
1470 | return PTR_ERR(entry); | |
1471 | ||
1472 | err = audit_del_rule(entry, | |
1473 | &audit_filter_list[entry->rule.listnr]); | |
5adc8a6a AG |
1474 | audit_log_rule_change(loginuid, sid, "remove", &entry->rule, |
1475 | !err); | |
5d330108 | 1476 | |
93315ed6 | 1477 | audit_free_rule(entry); |
fe7752ba DW |
1478 | break; |
1479 | default: | |
1480 | return -EINVAL; | |
1481 | } | |
1482 | ||
1483 | return err; | |
1484 | } | |
1485 | ||
1486 | int audit_comparator(const u32 left, const u32 op, const u32 right) | |
1487 | { | |
1488 | switch (op) { | |
1489 | case AUDIT_EQUAL: | |
1490 | return (left == right); | |
1491 | case AUDIT_NOT_EQUAL: | |
1492 | return (left != right); | |
1493 | case AUDIT_LESS_THAN: | |
1494 | return (left < right); | |
1495 | case AUDIT_LESS_THAN_OR_EQUAL: | |
1496 | return (left <= right); | |
1497 | case AUDIT_GREATER_THAN: | |
1498 | return (left > right); | |
1499 | case AUDIT_GREATER_THAN_OR_EQUAL: | |
1500 | return (left >= right); | |
fe7752ba | 1501 | } |
d9d9ec6e DK |
1502 | BUG(); |
1503 | return 0; | |
fe7752ba DW |
1504 | } |
1505 | ||
f368c07d AG |
1506 | /* Compare given dentry name with last component in given path, |
1507 | * return of 0 indicates a match. */ | |
9c937dcc AG |
1508 | int audit_compare_dname_path(const char *dname, const char *path, |
1509 | int *dirlen) | |
f368c07d AG |
1510 | { |
1511 | int dlen, plen; | |
1512 | const char *p; | |
1513 | ||
1514 | if (!dname || !path) | |
1515 | return 1; | |
1516 | ||
1517 | dlen = strlen(dname); | |
1518 | plen = strlen(path); | |
1519 | if (plen < dlen) | |
1520 | return 1; | |
1521 | ||
1522 | /* disregard trailing slashes */ | |
1523 | p = path + plen - 1; | |
1524 | while ((*p == '/') && (p > path)) | |
1525 | p--; | |
1526 | ||
1527 | /* find last path component */ | |
1528 | p = p - dlen + 1; | |
1529 | if (p < path) | |
1530 | return 1; | |
1531 | else if (p > path) { | |
1532 | if (*--p != '/') | |
1533 | return 1; | |
1534 | else | |
1535 | p++; | |
1536 | } | |
fe7752ba | 1537 | |
9c937dcc AG |
1538 | /* return length of path's directory component */ |
1539 | if (dirlen) | |
1540 | *dirlen = p - path; | |
f368c07d AG |
1541 | return strncmp(p, dname, dlen); |
1542 | } | |
fe7752ba DW |
1543 | |
1544 | static int audit_filter_user_rules(struct netlink_skb_parms *cb, | |
93315ed6 | 1545 | struct audit_krule *rule, |
fe7752ba DW |
1546 | enum audit_state *state) |
1547 | { | |
1548 | int i; | |
1549 | ||
1550 | for (i = 0; i < rule->field_count; i++) { | |
93315ed6 | 1551 | struct audit_field *f = &rule->fields[i]; |
fe7752ba DW |
1552 | int result = 0; |
1553 | ||
93315ed6 | 1554 | switch (f->type) { |
fe7752ba | 1555 | case AUDIT_PID: |
93315ed6 | 1556 | result = audit_comparator(cb->creds.pid, f->op, f->val); |
fe7752ba DW |
1557 | break; |
1558 | case AUDIT_UID: | |
93315ed6 | 1559 | result = audit_comparator(cb->creds.uid, f->op, f->val); |
fe7752ba DW |
1560 | break; |
1561 | case AUDIT_GID: | |
93315ed6 | 1562 | result = audit_comparator(cb->creds.gid, f->op, f->val); |
fe7752ba DW |
1563 | break; |
1564 | case AUDIT_LOGINUID: | |
93315ed6 | 1565 | result = audit_comparator(cb->loginuid, f->op, f->val); |
fe7752ba DW |
1566 | break; |
1567 | } | |
1568 | ||
1569 | if (!result) | |
1570 | return 0; | |
1571 | } | |
1572 | switch (rule->action) { | |
1573 | case AUDIT_NEVER: *state = AUDIT_DISABLED; break; | |
fe7752ba DW |
1574 | case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; |
1575 | } | |
1576 | return 1; | |
1577 | } | |
1578 | ||
1579 | int audit_filter_user(struct netlink_skb_parms *cb, int type) | |
1580 | { | |
1581 | struct audit_entry *e; | |
1582 | enum audit_state state; | |
1583 | int ret = 1; | |
1584 | ||
1585 | rcu_read_lock(); | |
1586 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { | |
1587 | if (audit_filter_user_rules(cb, &e->rule, &state)) { | |
1588 | if (state == AUDIT_DISABLED) | |
1589 | ret = 0; | |
1590 | break; | |
1591 | } | |
1592 | } | |
1593 | rcu_read_unlock(); | |
1594 | ||
1595 | return ret; /* Audit by default */ | |
1596 | } | |
1597 | ||
1598 | int audit_filter_type(int type) | |
1599 | { | |
1600 | struct audit_entry *e; | |
1601 | int result = 0; | |
1602 | ||
1603 | rcu_read_lock(); | |
1604 | if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE])) | |
1605 | goto unlock_and_return; | |
1606 | ||
1607 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE], | |
1608 | list) { | |
fe7752ba | 1609 | int i; |
93315ed6 AG |
1610 | for (i = 0; i < e->rule.field_count; i++) { |
1611 | struct audit_field *f = &e->rule.fields[i]; | |
1612 | if (f->type == AUDIT_MSGTYPE) { | |
1613 | result = audit_comparator(type, f->op, f->val); | |
fe7752ba DW |
1614 | if (!result) |
1615 | break; | |
1616 | } | |
1617 | } | |
1618 | if (result) | |
1619 | goto unlock_and_return; | |
1620 | } | |
1621 | unlock_and_return: | |
1622 | rcu_read_unlock(); | |
1623 | return result; | |
1624 | } | |
3dc7e315 DG |
1625 | |
1626 | /* Check to see if the rule contains any selinux fields. Returns 1 if there | |
1627 | are selinux fields specified in the rule, 0 otherwise. */ | |
1628 | static inline int audit_rule_has_selinux(struct audit_krule *rule) | |
1629 | { | |
1630 | int i; | |
1631 | ||
1632 | for (i = 0; i < rule->field_count; i++) { | |
1633 | struct audit_field *f = &rule->fields[i]; | |
1634 | switch (f->type) { | |
3a6b9f85 DG |
1635 | case AUDIT_SUBJ_USER: |
1636 | case AUDIT_SUBJ_ROLE: | |
1637 | case AUDIT_SUBJ_TYPE: | |
1638 | case AUDIT_SUBJ_SEN: | |
1639 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
1640 | case AUDIT_OBJ_USER: |
1641 | case AUDIT_OBJ_ROLE: | |
1642 | case AUDIT_OBJ_TYPE: | |
1643 | case AUDIT_OBJ_LEV_LOW: | |
1644 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
1645 | return 1; |
1646 | } | |
1647 | } | |
1648 | ||
1649 | return 0; | |
1650 | } | |
1651 | ||
1652 | /* This function will re-initialize the se_rule field of all applicable rules. | |
1653 | * It will traverse the filter lists serarching for rules that contain selinux | |
1654 | * specific filter fields. When such a rule is found, it is copied, the | |
1655 | * selinux field is re-initialized, and the old rule is replaced with the | |
1656 | * updated rule. */ | |
1657 | int selinux_audit_rule_update(void) | |
1658 | { | |
1659 | struct audit_entry *entry, *n, *nentry; | |
f368c07d | 1660 | struct audit_watch *watch; |
3dc7e315 DG |
1661 | int i, err = 0; |
1662 | ||
f368c07d AG |
1663 | /* audit_filter_mutex synchronizes the writers */ |
1664 | mutex_lock(&audit_filter_mutex); | |
3dc7e315 DG |
1665 | |
1666 | for (i = 0; i < AUDIT_NR_FILTERS; i++) { | |
1667 | list_for_each_entry_safe(entry, n, &audit_filter_list[i], list) { | |
1668 | if (!audit_rule_has_selinux(&entry->rule)) | |
1669 | continue; | |
1670 | ||
f368c07d AG |
1671 | watch = entry->rule.watch; |
1672 | nentry = audit_dupe_rule(&entry->rule, watch); | |
3dc7e315 DG |
1673 | if (unlikely(IS_ERR(nentry))) { |
1674 | /* save the first error encountered for the | |
1675 | * return value */ | |
1676 | if (!err) | |
1677 | err = PTR_ERR(nentry); | |
1678 | audit_panic("error updating selinux filters"); | |
f368c07d AG |
1679 | if (watch) |
1680 | list_del(&entry->rule.rlist); | |
3dc7e315 DG |
1681 | list_del_rcu(&entry->list); |
1682 | } else { | |
f368c07d AG |
1683 | if (watch) { |
1684 | list_add(&nentry->rule.rlist, | |
1685 | &watch->rules); | |
1686 | list_del(&entry->rule.rlist); | |
1687 | } | |
3dc7e315 DG |
1688 | list_replace_rcu(&entry->list, &nentry->list); |
1689 | } | |
1690 | call_rcu(&entry->rcu, audit_free_rule_rcu); | |
1691 | } | |
1692 | } | |
1693 | ||
f368c07d | 1694 | mutex_unlock(&audit_filter_mutex); |
3dc7e315 DG |
1695 | |
1696 | return err; | |
1697 | } | |
f368c07d AG |
1698 | |
1699 | /* Update watch data in audit rules based on inotify events. */ | |
1700 | void audit_handle_ievent(struct inotify_watch *i_watch, u32 wd, u32 mask, | |
1701 | u32 cookie, const char *dname, struct inode *inode) | |
1702 | { | |
1703 | struct audit_parent *parent; | |
1704 | ||
1705 | parent = container_of(i_watch, struct audit_parent, wdata); | |
1706 | ||
1707 | if (mask & (IN_CREATE|IN_MOVED_TO) && inode) | |
1708 | audit_update_watch(parent, dname, inode->i_sb->s_dev, | |
1709 | inode->i_ino, 0); | |
1710 | else if (mask & (IN_DELETE|IN_MOVED_FROM)) | |
1711 | audit_update_watch(parent, dname, (dev_t)-1, (unsigned long)-1, 1); | |
1712 | /* inotify automatically removes the watch and sends IN_IGNORED */ | |
1713 | else if (mask & (IN_DELETE_SELF|IN_UNMOUNT)) | |
1714 | audit_remove_parent_watches(parent); | |
1715 | /* inotify does not remove the watch, so remove it manually */ | |
1716 | else if(mask & IN_MOVE_SELF) { | |
1717 | audit_remove_parent_watches(parent); | |
1718 | inotify_remove_watch_locked(audit_ih, i_watch); | |
1719 | } else if (mask & IN_IGNORED) | |
1720 | put_inotify_watch(i_watch); | |
1721 | } |