Commit | Line | Data |
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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> | |
2a862b32 | 31 | #include <linux/security.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 | |
d7a96f3a | 41 | * LSM rules during filtering. If modified, these structures |
f368c07d AG |
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 | ||
74c3cbe3 | 90 | DEFINE_MUTEX(audit_filter_mutex); |
f368c07d | 91 | |
f368c07d AG |
92 | /* Inotify events we care about. */ |
93 | #define AUDIT_IN_WATCH IN_MOVE|IN_CREATE|IN_DELETE|IN_DELETE_SELF|IN_MOVE_SELF | |
94 | ||
95 | void audit_free_parent(struct inotify_watch *i_watch) | |
96 | { | |
97 | struct audit_parent *parent; | |
98 | ||
99 | parent = container_of(i_watch, struct audit_parent, wdata); | |
100 | WARN_ON(!list_empty(&parent->watches)); | |
101 | kfree(parent); | |
102 | } | |
103 | ||
104 | static inline void audit_get_watch(struct audit_watch *watch) | |
105 | { | |
106 | atomic_inc(&watch->count); | |
107 | } | |
108 | ||
109 | static void audit_put_watch(struct audit_watch *watch) | |
110 | { | |
111 | if (atomic_dec_and_test(&watch->count)) { | |
112 | WARN_ON(watch->parent); | |
113 | WARN_ON(!list_empty(&watch->rules)); | |
114 | kfree(watch->path); | |
115 | kfree(watch); | |
116 | } | |
117 | } | |
118 | ||
119 | static void audit_remove_watch(struct audit_watch *watch) | |
120 | { | |
121 | list_del(&watch->wlist); | |
122 | put_inotify_watch(&watch->parent->wdata); | |
123 | watch->parent = NULL; | |
124 | audit_put_watch(watch); /* match initial get */ | |
125 | } | |
126 | ||
93315ed6 | 127 | static inline void audit_free_rule(struct audit_entry *e) |
fe7752ba | 128 | { |
3dc7e315 | 129 | int i; |
f368c07d AG |
130 | |
131 | /* some rules don't have associated watches */ | |
132 | if (e->rule.watch) | |
133 | audit_put_watch(e->rule.watch); | |
3dc7e315 DG |
134 | if (e->rule.fields) |
135 | for (i = 0; i < e->rule.field_count; i++) { | |
136 | struct audit_field *f = &e->rule.fields[i]; | |
04305e4a AD |
137 | kfree(f->lsm_str); |
138 | security_audit_rule_free(f->lsm_rule); | |
3dc7e315 | 139 | } |
93315ed6 | 140 | kfree(e->rule.fields); |
5adc8a6a | 141 | kfree(e->rule.filterkey); |
93315ed6 AG |
142 | kfree(e); |
143 | } | |
144 | ||
74c3cbe3 | 145 | void audit_free_rule_rcu(struct rcu_head *head) |
93315ed6 AG |
146 | { |
147 | struct audit_entry *e = container_of(head, struct audit_entry, rcu); | |
148 | audit_free_rule(e); | |
149 | } | |
150 | ||
f368c07d AG |
151 | /* Initialize a parent watch entry. */ |
152 | static struct audit_parent *audit_init_parent(struct nameidata *ndp) | |
153 | { | |
154 | struct audit_parent *parent; | |
155 | s32 wd; | |
156 | ||
157 | parent = kzalloc(sizeof(*parent), GFP_KERNEL); | |
158 | if (unlikely(!parent)) | |
159 | return ERR_PTR(-ENOMEM); | |
160 | ||
161 | INIT_LIST_HEAD(&parent->watches); | |
162 | parent->flags = 0; | |
163 | ||
164 | inotify_init_watch(&parent->wdata); | |
165 | /* grab a ref so inotify watch hangs around until we take audit_filter_mutex */ | |
166 | get_inotify_watch(&parent->wdata); | |
4ac91378 JB |
167 | wd = inotify_add_watch(audit_ih, &parent->wdata, |
168 | ndp->path.dentry->d_inode, AUDIT_IN_WATCH); | |
f368c07d AG |
169 | if (wd < 0) { |
170 | audit_free_parent(&parent->wdata); | |
171 | return ERR_PTR(wd); | |
172 | } | |
173 | ||
174 | return parent; | |
175 | } | |
176 | ||
177 | /* Initialize a watch entry. */ | |
178 | static struct audit_watch *audit_init_watch(char *path) | |
179 | { | |
180 | struct audit_watch *watch; | |
181 | ||
182 | watch = kzalloc(sizeof(*watch), GFP_KERNEL); | |
183 | if (unlikely(!watch)) | |
184 | return ERR_PTR(-ENOMEM); | |
185 | ||
186 | INIT_LIST_HEAD(&watch->rules); | |
187 | atomic_set(&watch->count, 1); | |
188 | watch->path = path; | |
189 | watch->dev = (dev_t)-1; | |
190 | watch->ino = (unsigned long)-1; | |
191 | ||
192 | return watch; | |
193 | } | |
194 | ||
3dc7e315 DG |
195 | /* Initialize an audit filterlist entry. */ |
196 | static inline struct audit_entry *audit_init_entry(u32 field_count) | |
197 | { | |
198 | struct audit_entry *entry; | |
199 | struct audit_field *fields; | |
200 | ||
201 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
202 | if (unlikely(!entry)) | |
203 | return NULL; | |
204 | ||
205 | fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL); | |
206 | if (unlikely(!fields)) { | |
207 | kfree(entry); | |
208 | return NULL; | |
209 | } | |
210 | entry->rule.fields = fields; | |
211 | ||
212 | return entry; | |
213 | } | |
214 | ||
93315ed6 AG |
215 | /* Unpack a filter field's string representation from user-space |
216 | * buffer. */ | |
74c3cbe3 | 217 | char *audit_unpack_string(void **bufp, size_t *remain, size_t len) |
93315ed6 AG |
218 | { |
219 | char *str; | |
220 | ||
221 | if (!*bufp || (len == 0) || (len > *remain)) | |
222 | return ERR_PTR(-EINVAL); | |
223 | ||
224 | /* Of the currently implemented string fields, PATH_MAX | |
225 | * defines the longest valid length. | |
226 | */ | |
227 | if (len > PATH_MAX) | |
228 | return ERR_PTR(-ENAMETOOLONG); | |
229 | ||
230 | str = kmalloc(len + 1, GFP_KERNEL); | |
231 | if (unlikely(!str)) | |
232 | return ERR_PTR(-ENOMEM); | |
233 | ||
234 | memcpy(str, *bufp, len); | |
235 | str[len] = 0; | |
236 | *bufp += len; | |
237 | *remain -= len; | |
238 | ||
239 | return str; | |
240 | } | |
241 | ||
f368c07d AG |
242 | /* Translate an inode field to kernel respresentation. */ |
243 | static inline int audit_to_inode(struct audit_krule *krule, | |
244 | struct audit_field *f) | |
245 | { | |
246 | if (krule->listnr != AUDIT_FILTER_EXIT || | |
74c3cbe3 | 247 | krule->watch || krule->inode_f || krule->tree) |
f368c07d AG |
248 | return -EINVAL; |
249 | ||
250 | krule->inode_f = f; | |
251 | return 0; | |
252 | } | |
253 | ||
254 | /* Translate a watch string to kernel respresentation. */ | |
255 | static int audit_to_watch(struct audit_krule *krule, char *path, int len, | |
256 | u32 op) | |
257 | { | |
258 | struct audit_watch *watch; | |
259 | ||
260 | if (!audit_ih) | |
261 | return -EOPNOTSUPP; | |
262 | ||
263 | if (path[0] != '/' || path[len-1] == '/' || | |
264 | krule->listnr != AUDIT_FILTER_EXIT || | |
265 | op & ~AUDIT_EQUAL || | |
74c3cbe3 | 266 | krule->inode_f || krule->watch || krule->tree) |
f368c07d AG |
267 | return -EINVAL; |
268 | ||
269 | watch = audit_init_watch(path); | |
270 | if (unlikely(IS_ERR(watch))) | |
271 | return PTR_ERR(watch); | |
272 | ||
273 | audit_get_watch(watch); | |
274 | krule->watch = watch; | |
275 | ||
276 | return 0; | |
277 | } | |
278 | ||
b915543b AV |
279 | static __u32 *classes[AUDIT_SYSCALL_CLASSES]; |
280 | ||
281 | int __init audit_register_class(int class, unsigned *list) | |
282 | { | |
283 | __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL); | |
284 | if (!p) | |
285 | return -ENOMEM; | |
286 | while (*list != ~0U) { | |
287 | unsigned n = *list++; | |
288 | if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { | |
289 | kfree(p); | |
290 | return -EINVAL; | |
291 | } | |
292 | p[AUDIT_WORD(n)] |= AUDIT_BIT(n); | |
293 | } | |
294 | if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { | |
295 | kfree(p); | |
296 | return -EINVAL; | |
297 | } | |
298 | classes[class] = p; | |
299 | return 0; | |
300 | } | |
301 | ||
55669bfa AV |
302 | int audit_match_class(int class, unsigned syscall) |
303 | { | |
c926e4f4 | 304 | if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32)) |
55669bfa AV |
305 | return 0; |
306 | if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) | |
307 | return 0; | |
308 | return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); | |
309 | } | |
310 | ||
327b9eeb | 311 | #ifdef CONFIG_AUDITSYSCALL |
e54dc243 AG |
312 | static inline int audit_match_class_bits(int class, u32 *mask) |
313 | { | |
314 | int i; | |
315 | ||
316 | if (classes[class]) { | |
317 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
318 | if (mask[i] & classes[class][i]) | |
319 | return 0; | |
320 | } | |
321 | return 1; | |
322 | } | |
323 | ||
324 | static int audit_match_signal(struct audit_entry *entry) | |
325 | { | |
326 | struct audit_field *arch = entry->rule.arch_f; | |
327 | ||
328 | if (!arch) { | |
329 | /* When arch is unspecified, we must check both masks on biarch | |
330 | * as syscall number alone is ambiguous. */ | |
331 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
332 | entry->rule.mask) && | |
333 | audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
334 | entry->rule.mask)); | |
335 | } | |
336 | ||
337 | switch(audit_classify_arch(arch->val)) { | |
338 | case 0: /* native */ | |
339 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
340 | entry->rule.mask)); | |
341 | case 1: /* 32bit on biarch */ | |
342 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
343 | entry->rule.mask)); | |
344 | default: | |
345 | return 1; | |
346 | } | |
347 | } | |
327b9eeb | 348 | #endif |
e54dc243 | 349 | |
93315ed6 AG |
350 | /* Common user-space to kernel rule translation. */ |
351 | static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) | |
352 | { | |
353 | unsigned listnr; | |
354 | struct audit_entry *entry; | |
93315ed6 AG |
355 | int i, err; |
356 | ||
357 | err = -EINVAL; | |
358 | listnr = rule->flags & ~AUDIT_FILTER_PREPEND; | |
359 | switch(listnr) { | |
360 | default: | |
361 | goto exit_err; | |
362 | case AUDIT_FILTER_USER: | |
363 | case AUDIT_FILTER_TYPE: | |
364 | #ifdef CONFIG_AUDITSYSCALL | |
365 | case AUDIT_FILTER_ENTRY: | |
366 | case AUDIT_FILTER_EXIT: | |
367 | case AUDIT_FILTER_TASK: | |
368 | #endif | |
369 | ; | |
370 | } | |
014149cc AV |
371 | if (unlikely(rule->action == AUDIT_POSSIBLE)) { |
372 | printk(KERN_ERR "AUDIT_POSSIBLE is deprecated\n"); | |
373 | goto exit_err; | |
374 | } | |
375 | if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS) | |
93315ed6 AG |
376 | goto exit_err; |
377 | if (rule->field_count > AUDIT_MAX_FIELDS) | |
378 | goto exit_err; | |
379 | ||
380 | err = -ENOMEM; | |
3dc7e315 DG |
381 | entry = audit_init_entry(rule->field_count); |
382 | if (!entry) | |
93315ed6 | 383 | goto exit_err; |
93315ed6 AG |
384 | |
385 | entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND; | |
386 | entry->rule.listnr = listnr; | |
387 | entry->rule.action = rule->action; | |
388 | entry->rule.field_count = rule->field_count; | |
93315ed6 AG |
389 | |
390 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
391 | entry->rule.mask[i] = rule->mask[i]; | |
392 | ||
b915543b AV |
393 | for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { |
394 | int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; | |
395 | __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; | |
396 | __u32 *class; | |
397 | ||
398 | if (!(*p & AUDIT_BIT(bit))) | |
399 | continue; | |
400 | *p &= ~AUDIT_BIT(bit); | |
401 | class = classes[i]; | |
402 | if (class) { | |
403 | int j; | |
404 | for (j = 0; j < AUDIT_BITMASK_SIZE; j++) | |
405 | entry->rule.mask[j] |= class[j]; | |
406 | } | |
407 | } | |
408 | ||
93315ed6 AG |
409 | return entry; |
410 | ||
411 | exit_err: | |
412 | return ERR_PTR(err); | |
413 | } | |
414 | ||
415 | /* Translate struct audit_rule to kernel's rule respresentation. | |
416 | * Exists for backward compatibility with userspace. */ | |
417 | static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) | |
418 | { | |
419 | struct audit_entry *entry; | |
f368c07d | 420 | struct audit_field *f; |
93315ed6 | 421 | int err = 0; |
fe7752ba DW |
422 | int i; |
423 | ||
93315ed6 AG |
424 | entry = audit_to_entry_common(rule); |
425 | if (IS_ERR(entry)) | |
426 | goto exit_nofree; | |
427 | ||
428 | for (i = 0; i < rule->field_count; i++) { | |
429 | struct audit_field *f = &entry->rule.fields[i]; | |
430 | ||
93315ed6 AG |
431 | f->op = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS); |
432 | f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS); | |
433 | f->val = rule->values[i]; | |
434 | ||
f368c07d | 435 | err = -EINVAL; |
f368c07d | 436 | switch(f->type) { |
0a73dccc | 437 | default: |
3dc7e315 | 438 | goto exit_free; |
0a73dccc AV |
439 | case AUDIT_PID: |
440 | case AUDIT_UID: | |
441 | case AUDIT_EUID: | |
442 | case AUDIT_SUID: | |
443 | case AUDIT_FSUID: | |
444 | case AUDIT_GID: | |
445 | case AUDIT_EGID: | |
446 | case AUDIT_SGID: | |
447 | case AUDIT_FSGID: | |
448 | case AUDIT_LOGINUID: | |
449 | case AUDIT_PERS: | |
0a73dccc | 450 | case AUDIT_MSGTYPE: |
3b33ac31 | 451 | case AUDIT_PPID: |
0a73dccc AV |
452 | case AUDIT_DEVMAJOR: |
453 | case AUDIT_DEVMINOR: | |
454 | case AUDIT_EXIT: | |
455 | case AUDIT_SUCCESS: | |
74f2345b EP |
456 | /* bit ops are only useful on syscall args */ |
457 | if (f->op == AUDIT_BIT_MASK || | |
458 | f->op == AUDIT_BIT_TEST) { | |
459 | err = -EINVAL; | |
460 | goto exit_free; | |
461 | } | |
462 | break; | |
0a73dccc AV |
463 | case AUDIT_ARG0: |
464 | case AUDIT_ARG1: | |
465 | case AUDIT_ARG2: | |
466 | case AUDIT_ARG3: | |
467 | break; | |
4b8a311b EP |
468 | /* arch is only allowed to be = or != */ |
469 | case AUDIT_ARCH: | |
470 | if ((f->op != AUDIT_NOT_EQUAL) && (f->op != AUDIT_EQUAL) | |
471 | && (f->op != AUDIT_NEGATE) && (f->op)) { | |
472 | err = -EINVAL; | |
473 | goto exit_free; | |
474 | } | |
e54dc243 | 475 | entry->rule.arch_f = f; |
4b8a311b | 476 | break; |
55669bfa AV |
477 | case AUDIT_PERM: |
478 | if (f->val & ~15) | |
479 | goto exit_free; | |
480 | break; | |
f368c07d AG |
481 | case AUDIT_INODE: |
482 | err = audit_to_inode(&entry->rule, f); | |
483 | if (err) | |
484 | goto exit_free; | |
485 | break; | |
3dc7e315 DG |
486 | } |
487 | ||
93315ed6 | 488 | entry->rule.vers_ops = (f->op & AUDIT_OPERATORS) ? 2 : 1; |
d9d9ec6e DK |
489 | |
490 | /* Support for legacy operators where | |
491 | * AUDIT_NEGATE bit signifies != and otherwise assumes == */ | |
93315ed6 | 492 | if (f->op & AUDIT_NEGATE) |
d9d9ec6e DK |
493 | f->op = AUDIT_NOT_EQUAL; |
494 | else if (!f->op) | |
495 | f->op = AUDIT_EQUAL; | |
496 | else if (f->op == AUDIT_OPERATORS) { | |
497 | err = -EINVAL; | |
498 | goto exit_free; | |
499 | } | |
fe7752ba | 500 | } |
93315ed6 | 501 | |
f368c07d AG |
502 | f = entry->rule.inode_f; |
503 | if (f) { | |
504 | switch(f->op) { | |
505 | case AUDIT_NOT_EQUAL: | |
506 | entry->rule.inode_f = NULL; | |
507 | case AUDIT_EQUAL: | |
508 | break; | |
509 | default: | |
5422e01a | 510 | err = -EINVAL; |
f368c07d AG |
511 | goto exit_free; |
512 | } | |
513 | } | |
514 | ||
93315ed6 AG |
515 | exit_nofree: |
516 | return entry; | |
517 | ||
518 | exit_free: | |
519 | audit_free_rule(entry); | |
520 | return ERR_PTR(err); | |
fe7752ba DW |
521 | } |
522 | ||
93315ed6 AG |
523 | /* Translate struct audit_rule_data to kernel's rule respresentation. */ |
524 | static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, | |
525 | size_t datasz) | |
fe7752ba | 526 | { |
93315ed6 AG |
527 | int err = 0; |
528 | struct audit_entry *entry; | |
f368c07d | 529 | struct audit_field *f; |
93315ed6 | 530 | void *bufp; |
3dc7e315 | 531 | size_t remain = datasz - sizeof(struct audit_rule_data); |
fe7752ba | 532 | int i; |
3dc7e315 | 533 | char *str; |
fe7752ba | 534 | |
93315ed6 AG |
535 | entry = audit_to_entry_common((struct audit_rule *)data); |
536 | if (IS_ERR(entry)) | |
537 | goto exit_nofree; | |
fe7752ba | 538 | |
93315ed6 AG |
539 | bufp = data->buf; |
540 | entry->rule.vers_ops = 2; | |
541 | for (i = 0; i < data->field_count; i++) { | |
542 | struct audit_field *f = &entry->rule.fields[i]; | |
543 | ||
544 | err = -EINVAL; | |
545 | if (!(data->fieldflags[i] & AUDIT_OPERATORS) || | |
546 | data->fieldflags[i] & ~AUDIT_OPERATORS) | |
547 | goto exit_free; | |
548 | ||
549 | f->op = data->fieldflags[i] & AUDIT_OPERATORS; | |
550 | f->type = data->fields[i]; | |
3dc7e315 | 551 | f->val = data->values[i]; |
04305e4a AD |
552 | f->lsm_str = NULL; |
553 | f->lsm_rule = NULL; | |
93315ed6 | 554 | switch(f->type) { |
0a73dccc AV |
555 | case AUDIT_PID: |
556 | case AUDIT_UID: | |
557 | case AUDIT_EUID: | |
558 | case AUDIT_SUID: | |
559 | case AUDIT_FSUID: | |
560 | case AUDIT_GID: | |
561 | case AUDIT_EGID: | |
562 | case AUDIT_SGID: | |
563 | case AUDIT_FSGID: | |
564 | case AUDIT_LOGINUID: | |
565 | case AUDIT_PERS: | |
0a73dccc AV |
566 | case AUDIT_MSGTYPE: |
567 | case AUDIT_PPID: | |
568 | case AUDIT_DEVMAJOR: | |
569 | case AUDIT_DEVMINOR: | |
570 | case AUDIT_EXIT: | |
571 | case AUDIT_SUCCESS: | |
572 | case AUDIT_ARG0: | |
573 | case AUDIT_ARG1: | |
574 | case AUDIT_ARG2: | |
575 | case AUDIT_ARG3: | |
576 | break; | |
e54dc243 AG |
577 | case AUDIT_ARCH: |
578 | entry->rule.arch_f = f; | |
579 | break; | |
3a6b9f85 DG |
580 | case AUDIT_SUBJ_USER: |
581 | case AUDIT_SUBJ_ROLE: | |
582 | case AUDIT_SUBJ_TYPE: | |
583 | case AUDIT_SUBJ_SEN: | |
584 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
585 | case AUDIT_OBJ_USER: |
586 | case AUDIT_OBJ_ROLE: | |
587 | case AUDIT_OBJ_TYPE: | |
588 | case AUDIT_OBJ_LEV_LOW: | |
589 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
590 | str = audit_unpack_string(&bufp, &remain, f->val); |
591 | if (IS_ERR(str)) | |
592 | goto exit_free; | |
593 | entry->rule.buflen += f->val; | |
594 | ||
d7a96f3a | 595 | err = security_audit_rule_init(f->type, f->op, str, |
04305e4a | 596 | (void **)&f->lsm_rule); |
3dc7e315 DG |
597 | /* Keep currently invalid fields around in case they |
598 | * become valid after a policy reload. */ | |
599 | if (err == -EINVAL) { | |
d7a96f3a | 600 | printk(KERN_WARNING "audit rule for LSM " |
3dc7e315 DG |
601 | "\'%s\' is invalid\n", str); |
602 | err = 0; | |
603 | } | |
604 | if (err) { | |
605 | kfree(str); | |
606 | goto exit_free; | |
607 | } else | |
04305e4a | 608 | f->lsm_str = str; |
3dc7e315 | 609 | break; |
f368c07d AG |
610 | case AUDIT_WATCH: |
611 | str = audit_unpack_string(&bufp, &remain, f->val); | |
612 | if (IS_ERR(str)) | |
613 | goto exit_free; | |
614 | entry->rule.buflen += f->val; | |
615 | ||
616 | err = audit_to_watch(&entry->rule, str, f->val, f->op); | |
617 | if (err) { | |
618 | kfree(str); | |
619 | goto exit_free; | |
620 | } | |
621 | break; | |
74c3cbe3 AV |
622 | case AUDIT_DIR: |
623 | str = audit_unpack_string(&bufp, &remain, f->val); | |
624 | if (IS_ERR(str)) | |
625 | goto exit_free; | |
626 | entry->rule.buflen += f->val; | |
627 | ||
628 | err = audit_make_tree(&entry->rule, str, f->op); | |
629 | kfree(str); | |
630 | if (err) | |
631 | goto exit_free; | |
632 | break; | |
f368c07d AG |
633 | case AUDIT_INODE: |
634 | err = audit_to_inode(&entry->rule, f); | |
635 | if (err) | |
636 | goto exit_free; | |
637 | break; | |
5adc8a6a AG |
638 | case AUDIT_FILTERKEY: |
639 | err = -EINVAL; | |
640 | if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN) | |
641 | goto exit_free; | |
642 | str = audit_unpack_string(&bufp, &remain, f->val); | |
643 | if (IS_ERR(str)) | |
644 | goto exit_free; | |
645 | entry->rule.buflen += f->val; | |
646 | entry->rule.filterkey = str; | |
647 | break; | |
55669bfa AV |
648 | case AUDIT_PERM: |
649 | if (f->val & ~15) | |
650 | goto exit_free; | |
651 | break; | |
0a73dccc AV |
652 | default: |
653 | goto exit_free; | |
f368c07d AG |
654 | } |
655 | } | |
656 | ||
657 | f = entry->rule.inode_f; | |
658 | if (f) { | |
659 | switch(f->op) { | |
660 | case AUDIT_NOT_EQUAL: | |
661 | entry->rule.inode_f = NULL; | |
662 | case AUDIT_EQUAL: | |
663 | break; | |
664 | default: | |
5422e01a | 665 | err = -EINVAL; |
f368c07d | 666 | goto exit_free; |
93315ed6 AG |
667 | } |
668 | } | |
669 | ||
670 | exit_nofree: | |
671 | return entry; | |
672 | ||
673 | exit_free: | |
674 | audit_free_rule(entry); | |
675 | return ERR_PTR(err); | |
676 | } | |
677 | ||
678 | /* Pack a filter field's string representation into data block. */ | |
74c3cbe3 | 679 | static inline size_t audit_pack_string(void **bufp, const char *str) |
93315ed6 AG |
680 | { |
681 | size_t len = strlen(str); | |
682 | ||
683 | memcpy(*bufp, str, len); | |
684 | *bufp += len; | |
685 | ||
686 | return len; | |
687 | } | |
688 | ||
689 | /* Translate kernel rule respresentation to struct audit_rule. | |
690 | * Exists for backward compatibility with userspace. */ | |
691 | static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule) | |
692 | { | |
693 | struct audit_rule *rule; | |
694 | int i; | |
695 | ||
4668edc3 | 696 | rule = kzalloc(sizeof(*rule), GFP_KERNEL); |
93315ed6 | 697 | if (unlikely(!rule)) |
0a3b483e | 698 | return NULL; |
93315ed6 AG |
699 | |
700 | rule->flags = krule->flags | krule->listnr; | |
701 | rule->action = krule->action; | |
702 | rule->field_count = krule->field_count; | |
703 | for (i = 0; i < rule->field_count; i++) { | |
704 | rule->values[i] = krule->fields[i].val; | |
705 | rule->fields[i] = krule->fields[i].type; | |
706 | ||
707 | if (krule->vers_ops == 1) { | |
708 | if (krule->fields[i].op & AUDIT_NOT_EQUAL) | |
709 | rule->fields[i] |= AUDIT_NEGATE; | |
710 | } else { | |
711 | rule->fields[i] |= krule->fields[i].op; | |
712 | } | |
713 | } | |
714 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i]; | |
715 | ||
716 | return rule; | |
717 | } | |
fe7752ba | 718 | |
93315ed6 AG |
719 | /* Translate kernel rule respresentation to struct audit_rule_data. */ |
720 | static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) | |
721 | { | |
722 | struct audit_rule_data *data; | |
723 | void *bufp; | |
724 | int i; | |
725 | ||
726 | data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); | |
727 | if (unlikely(!data)) | |
0a3b483e | 728 | return NULL; |
93315ed6 AG |
729 | memset(data, 0, sizeof(*data)); |
730 | ||
731 | data->flags = krule->flags | krule->listnr; | |
732 | data->action = krule->action; | |
733 | data->field_count = krule->field_count; | |
734 | bufp = data->buf; | |
735 | for (i = 0; i < data->field_count; i++) { | |
736 | struct audit_field *f = &krule->fields[i]; | |
737 | ||
738 | data->fields[i] = f->type; | |
739 | data->fieldflags[i] = f->op; | |
740 | switch(f->type) { | |
3a6b9f85 DG |
741 | case AUDIT_SUBJ_USER: |
742 | case AUDIT_SUBJ_ROLE: | |
743 | case AUDIT_SUBJ_TYPE: | |
744 | case AUDIT_SUBJ_SEN: | |
745 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
746 | case AUDIT_OBJ_USER: |
747 | case AUDIT_OBJ_ROLE: | |
748 | case AUDIT_OBJ_TYPE: | |
749 | case AUDIT_OBJ_LEV_LOW: | |
750 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 | 751 | data->buflen += data->values[i] = |
04305e4a | 752 | audit_pack_string(&bufp, f->lsm_str); |
3dc7e315 | 753 | break; |
f368c07d AG |
754 | case AUDIT_WATCH: |
755 | data->buflen += data->values[i] = | |
756 | audit_pack_string(&bufp, krule->watch->path); | |
757 | break; | |
74c3cbe3 AV |
758 | case AUDIT_DIR: |
759 | data->buflen += data->values[i] = | |
760 | audit_pack_string(&bufp, | |
761 | audit_tree_path(krule->tree)); | |
762 | break; | |
5adc8a6a AG |
763 | case AUDIT_FILTERKEY: |
764 | data->buflen += data->values[i] = | |
765 | audit_pack_string(&bufp, krule->filterkey); | |
766 | break; | |
93315ed6 AG |
767 | default: |
768 | data->values[i] = f->val; | |
769 | } | |
770 | } | |
771 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i]; | |
772 | ||
773 | return data; | |
774 | } | |
775 | ||
776 | /* Compare two rules in kernel format. Considered success if rules | |
777 | * don't match. */ | |
778 | static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) | |
779 | { | |
780 | int i; | |
781 | ||
782 | if (a->flags != b->flags || | |
783 | a->listnr != b->listnr || | |
784 | a->action != b->action || | |
785 | a->field_count != b->field_count) | |
fe7752ba DW |
786 | return 1; |
787 | ||
788 | for (i = 0; i < a->field_count; i++) { | |
93315ed6 AG |
789 | if (a->fields[i].type != b->fields[i].type || |
790 | a->fields[i].op != b->fields[i].op) | |
fe7752ba | 791 | return 1; |
93315ed6 AG |
792 | |
793 | switch(a->fields[i].type) { | |
3a6b9f85 DG |
794 | case AUDIT_SUBJ_USER: |
795 | case AUDIT_SUBJ_ROLE: | |
796 | case AUDIT_SUBJ_TYPE: | |
797 | case AUDIT_SUBJ_SEN: | |
798 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
799 | case AUDIT_OBJ_USER: |
800 | case AUDIT_OBJ_ROLE: | |
801 | case AUDIT_OBJ_TYPE: | |
802 | case AUDIT_OBJ_LEV_LOW: | |
803 | case AUDIT_OBJ_LEV_HIGH: | |
04305e4a | 804 | if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str)) |
3dc7e315 DG |
805 | return 1; |
806 | break; | |
f368c07d AG |
807 | case AUDIT_WATCH: |
808 | if (strcmp(a->watch->path, b->watch->path)) | |
809 | return 1; | |
810 | break; | |
74c3cbe3 AV |
811 | case AUDIT_DIR: |
812 | if (strcmp(audit_tree_path(a->tree), | |
813 | audit_tree_path(b->tree))) | |
814 | return 1; | |
815 | break; | |
5adc8a6a AG |
816 | case AUDIT_FILTERKEY: |
817 | /* both filterkeys exist based on above type compare */ | |
818 | if (strcmp(a->filterkey, b->filterkey)) | |
819 | return 1; | |
820 | break; | |
93315ed6 AG |
821 | default: |
822 | if (a->fields[i].val != b->fields[i].val) | |
823 | return 1; | |
824 | } | |
fe7752ba DW |
825 | } |
826 | ||
827 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
828 | if (a->mask[i] != b->mask[i]) | |
829 | return 1; | |
830 | ||
831 | return 0; | |
832 | } | |
833 | ||
f368c07d AG |
834 | /* Duplicate the given audit watch. The new watch's rules list is initialized |
835 | * to an empty list and wlist is undefined. */ | |
836 | static struct audit_watch *audit_dupe_watch(struct audit_watch *old) | |
837 | { | |
838 | char *path; | |
839 | struct audit_watch *new; | |
840 | ||
841 | path = kstrdup(old->path, GFP_KERNEL); | |
842 | if (unlikely(!path)) | |
843 | return ERR_PTR(-ENOMEM); | |
844 | ||
845 | new = audit_init_watch(path); | |
846 | if (unlikely(IS_ERR(new))) { | |
847 | kfree(path); | |
848 | goto out; | |
849 | } | |
850 | ||
851 | new->dev = old->dev; | |
852 | new->ino = old->ino; | |
853 | get_inotify_watch(&old->parent->wdata); | |
854 | new->parent = old->parent; | |
855 | ||
856 | out: | |
857 | return new; | |
858 | } | |
859 | ||
04305e4a | 860 | /* Duplicate LSM field information. The lsm_rule is opaque, so must be |
3dc7e315 | 861 | * re-initialized. */ |
d7a96f3a | 862 | static inline int audit_dupe_lsm_field(struct audit_field *df, |
3dc7e315 DG |
863 | struct audit_field *sf) |
864 | { | |
865 | int ret = 0; | |
04305e4a | 866 | char *lsm_str; |
3dc7e315 | 867 | |
04305e4a AD |
868 | /* our own copy of lsm_str */ |
869 | lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL); | |
870 | if (unlikely(!lsm_str)) | |
3e1fbd12 | 871 | return -ENOMEM; |
04305e4a | 872 | df->lsm_str = lsm_str; |
3dc7e315 | 873 | |
04305e4a AD |
874 | /* our own (refreshed) copy of lsm_rule */ |
875 | ret = security_audit_rule_init(df->type, df->op, df->lsm_str, | |
876 | (void **)&df->lsm_rule); | |
3dc7e315 DG |
877 | /* Keep currently invalid fields around in case they |
878 | * become valid after a policy reload. */ | |
879 | if (ret == -EINVAL) { | |
d7a96f3a | 880 | printk(KERN_WARNING "audit rule for LSM \'%s\' is " |
04305e4a | 881 | "invalid\n", df->lsm_str); |
3dc7e315 DG |
882 | ret = 0; |
883 | } | |
884 | ||
885 | return ret; | |
886 | } | |
887 | ||
888 | /* Duplicate an audit rule. This will be a deep copy with the exception | |
d7a96f3a | 889 | * of the watch - that pointer is carried over. The LSM specific fields |
3dc7e315 | 890 | * will be updated in the copy. The point is to be able to replace the old |
f368c07d AG |
891 | * rule with the new rule in the filterlist, then free the old rule. |
892 | * The rlist element is undefined; list manipulations are handled apart from | |
893 | * the initial copy. */ | |
894 | static struct audit_entry *audit_dupe_rule(struct audit_krule *old, | |
895 | struct audit_watch *watch) | |
3dc7e315 DG |
896 | { |
897 | u32 fcount = old->field_count; | |
898 | struct audit_entry *entry; | |
899 | struct audit_krule *new; | |
5adc8a6a | 900 | char *fk; |
3dc7e315 DG |
901 | int i, err = 0; |
902 | ||
903 | entry = audit_init_entry(fcount); | |
904 | if (unlikely(!entry)) | |
905 | return ERR_PTR(-ENOMEM); | |
906 | ||
907 | new = &entry->rule; | |
908 | new->vers_ops = old->vers_ops; | |
909 | new->flags = old->flags; | |
910 | new->listnr = old->listnr; | |
911 | new->action = old->action; | |
912 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
913 | new->mask[i] = old->mask[i]; | |
914 | new->buflen = old->buflen; | |
f368c07d AG |
915 | new->inode_f = old->inode_f; |
916 | new->watch = NULL; | |
3dc7e315 | 917 | new->field_count = old->field_count; |
74c3cbe3 AV |
918 | /* |
919 | * note that we are OK with not refcounting here; audit_match_tree() | |
920 | * never dereferences tree and we can't get false positives there | |
921 | * since we'd have to have rule gone from the list *and* removed | |
922 | * before the chunks found by lookup had been allocated, i.e. before | |
923 | * the beginning of list scan. | |
924 | */ | |
925 | new->tree = old->tree; | |
3dc7e315 DG |
926 | memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount); |
927 | ||
04305e4a | 928 | /* deep copy this information, updating the lsm_rule fields, because |
3dc7e315 DG |
929 | * the originals will all be freed when the old rule is freed. */ |
930 | for (i = 0; i < fcount; i++) { | |
931 | switch (new->fields[i].type) { | |
3a6b9f85 DG |
932 | case AUDIT_SUBJ_USER: |
933 | case AUDIT_SUBJ_ROLE: | |
934 | case AUDIT_SUBJ_TYPE: | |
935 | case AUDIT_SUBJ_SEN: | |
936 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
937 | case AUDIT_OBJ_USER: |
938 | case AUDIT_OBJ_ROLE: | |
939 | case AUDIT_OBJ_TYPE: | |
940 | case AUDIT_OBJ_LEV_LOW: | |
941 | case AUDIT_OBJ_LEV_HIGH: | |
d7a96f3a | 942 | err = audit_dupe_lsm_field(&new->fields[i], |
3dc7e315 | 943 | &old->fields[i]); |
5adc8a6a AG |
944 | break; |
945 | case AUDIT_FILTERKEY: | |
946 | fk = kstrdup(old->filterkey, GFP_KERNEL); | |
947 | if (unlikely(!fk)) | |
948 | err = -ENOMEM; | |
949 | else | |
950 | new->filterkey = fk; | |
3dc7e315 DG |
951 | } |
952 | if (err) { | |
953 | audit_free_rule(entry); | |
954 | return ERR_PTR(err); | |
955 | } | |
956 | } | |
957 | ||
f368c07d AG |
958 | if (watch) { |
959 | audit_get_watch(watch); | |
960 | new->watch = watch; | |
961 | } | |
962 | ||
3dc7e315 DG |
963 | return entry; |
964 | } | |
965 | ||
f368c07d AG |
966 | /* Update inode info in audit rules based on filesystem event. */ |
967 | static void audit_update_watch(struct audit_parent *parent, | |
968 | const char *dname, dev_t dev, | |
969 | unsigned long ino, unsigned invalidating) | |
970 | { | |
971 | struct audit_watch *owatch, *nwatch, *nextw; | |
972 | struct audit_krule *r, *nextr; | |
973 | struct audit_entry *oentry, *nentry; | |
f368c07d AG |
974 | |
975 | mutex_lock(&audit_filter_mutex); | |
976 | list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) { | |
9c937dcc | 977 | if (audit_compare_dname_path(dname, owatch->path, NULL)) |
f368c07d AG |
978 | continue; |
979 | ||
980 | /* If the update involves invalidating rules, do the inode-based | |
981 | * filtering now, so we don't omit records. */ | |
7b018b28 | 982 | if (invalidating && current->audit_context && |
f368c07d AG |
983 | audit_filter_inodes(current, current->audit_context) == AUDIT_RECORD_CONTEXT) |
984 | audit_set_auditable(current->audit_context); | |
985 | ||
986 | nwatch = audit_dupe_watch(owatch); | |
987 | if (unlikely(IS_ERR(nwatch))) { | |
988 | mutex_unlock(&audit_filter_mutex); | |
989 | audit_panic("error updating watch, skipping"); | |
990 | return; | |
991 | } | |
992 | nwatch->dev = dev; | |
993 | nwatch->ino = ino; | |
994 | ||
995 | list_for_each_entry_safe(r, nextr, &owatch->rules, rlist) { | |
996 | ||
997 | oentry = container_of(r, struct audit_entry, rule); | |
998 | list_del(&oentry->rule.rlist); | |
999 | list_del_rcu(&oentry->list); | |
1000 | ||
1001 | nentry = audit_dupe_rule(&oentry->rule, nwatch); | |
1002 | if (unlikely(IS_ERR(nentry))) | |
1003 | audit_panic("error updating watch, removing"); | |
1004 | else { | |
1005 | int h = audit_hash_ino((u32)ino); | |
1006 | list_add(&nentry->rule.rlist, &nwatch->rules); | |
1007 | list_add_rcu(&nentry->list, &audit_inode_hash[h]); | |
1008 | } | |
1009 | ||
1010 | call_rcu(&oentry->rcu, audit_free_rule_rcu); | |
1011 | } | |
1012 | ||
1a6b9f23 EP |
1013 | if (audit_enabled) { |
1014 | struct audit_buffer *ab; | |
1015 | ab = audit_log_start(NULL, GFP_KERNEL, | |
1016 | AUDIT_CONFIG_CHANGE); | |
1017 | audit_log_format(ab, | |
1018 | "op=updated rules specifying path="); | |
1019 | audit_log_untrustedstring(ab, owatch->path); | |
1020 | audit_log_format(ab, " with dev=%u ino=%lu\n", | |
1021 | dev, ino); | |
1022 | audit_log_format(ab, " list=%d res=1", r->listnr); | |
1023 | audit_log_end(ab); | |
1024 | } | |
f368c07d AG |
1025 | audit_remove_watch(owatch); |
1026 | goto add_watch_to_parent; /* event applies to a single watch */ | |
1027 | } | |
1028 | mutex_unlock(&audit_filter_mutex); | |
1029 | return; | |
1030 | ||
1031 | add_watch_to_parent: | |
1032 | list_add(&nwatch->wlist, &parent->watches); | |
1033 | mutex_unlock(&audit_filter_mutex); | |
1034 | return; | |
1035 | } | |
1036 | ||
1037 | /* Remove all watches & rules associated with a parent that is going away. */ | |
1038 | static void audit_remove_parent_watches(struct audit_parent *parent) | |
1039 | { | |
1040 | struct audit_watch *w, *nextw; | |
1041 | struct audit_krule *r, *nextr; | |
1042 | struct audit_entry *e; | |
1043 | ||
1044 | mutex_lock(&audit_filter_mutex); | |
1045 | parent->flags |= AUDIT_PARENT_INVALID; | |
1046 | list_for_each_entry_safe(w, nextw, &parent->watches, wlist) { | |
1047 | list_for_each_entry_safe(r, nextr, &w->rules, rlist) { | |
1048 | e = container_of(r, struct audit_entry, rule); | |
1a6b9f23 EP |
1049 | if (audit_enabled) { |
1050 | struct audit_buffer *ab; | |
1051 | ab = audit_log_start(NULL, GFP_KERNEL, | |
1052 | AUDIT_CONFIG_CHANGE); | |
1053 | audit_log_format(ab, "op=remove rule path="); | |
1054 | audit_log_untrustedstring(ab, w->path); | |
1055 | if (r->filterkey) { | |
1056 | audit_log_format(ab, " key="); | |
1057 | audit_log_untrustedstring(ab, | |
1058 | r->filterkey); | |
1059 | } else | |
1060 | audit_log_format(ab, " key=(null)"); | |
1061 | audit_log_format(ab, " list=%d res=1", | |
1062 | r->listnr); | |
1063 | audit_log_end(ab); | |
1064 | } | |
f368c07d AG |
1065 | list_del(&r->rlist); |
1066 | list_del_rcu(&e->list); | |
1067 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
f368c07d AG |
1068 | } |
1069 | audit_remove_watch(w); | |
1070 | } | |
1071 | mutex_unlock(&audit_filter_mutex); | |
1072 | } | |
1073 | ||
1074 | /* Unregister inotify watches for parents on in_list. | |
1075 | * Generates an IN_IGNORED event. */ | |
1076 | static void audit_inotify_unregister(struct list_head *in_list) | |
1077 | { | |
1078 | struct audit_parent *p, *n; | |
1079 | ||
1080 | list_for_each_entry_safe(p, n, in_list, ilist) { | |
1081 | list_del(&p->ilist); | |
1082 | inotify_rm_watch(audit_ih, &p->wdata); | |
1083 | /* the put matching the get in audit_do_del_rule() */ | |
1084 | put_inotify_watch(&p->wdata); | |
1085 | } | |
1086 | } | |
1087 | ||
1088 | /* Find an existing audit rule. | |
1089 | * Caller must hold audit_filter_mutex to prevent stale rule data. */ | |
1090 | static struct audit_entry *audit_find_rule(struct audit_entry *entry, | |
1091 | struct list_head *list) | |
1092 | { | |
1093 | struct audit_entry *e, *found = NULL; | |
1094 | int h; | |
1095 | ||
1096 | if (entry->rule.watch) { | |
1097 | /* we don't know the inode number, so must walk entire hash */ | |
1098 | for (h = 0; h < AUDIT_INODE_BUCKETS; h++) { | |
1099 | list = &audit_inode_hash[h]; | |
1100 | list_for_each_entry(e, list, list) | |
1101 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
1102 | found = e; | |
1103 | goto out; | |
1104 | } | |
1105 | } | |
1106 | goto out; | |
1107 | } | |
1108 | ||
1109 | list_for_each_entry(e, list, list) | |
1110 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
1111 | found = e; | |
1112 | goto out; | |
1113 | } | |
1114 | ||
1115 | out: | |
1116 | return found; | |
1117 | } | |
1118 | ||
1119 | /* Get path information necessary for adding watches. */ | |
1120 | static int audit_get_nd(char *path, struct nameidata **ndp, | |
1121 | struct nameidata **ndw) | |
1122 | { | |
1123 | struct nameidata *ndparent, *ndwatch; | |
1124 | int err; | |
1125 | ||
1126 | ndparent = kmalloc(sizeof(*ndparent), GFP_KERNEL); | |
1127 | if (unlikely(!ndparent)) | |
1128 | return -ENOMEM; | |
1129 | ||
1130 | ndwatch = kmalloc(sizeof(*ndwatch), GFP_KERNEL); | |
1131 | if (unlikely(!ndwatch)) { | |
1132 | kfree(ndparent); | |
1133 | return -ENOMEM; | |
1134 | } | |
1135 | ||
1136 | err = path_lookup(path, LOOKUP_PARENT, ndparent); | |
1137 | if (err) { | |
1138 | kfree(ndparent); | |
1139 | kfree(ndwatch); | |
1140 | return err; | |
1141 | } | |
1142 | ||
1143 | err = path_lookup(path, 0, ndwatch); | |
1144 | if (err) { | |
1145 | kfree(ndwatch); | |
1146 | ndwatch = NULL; | |
1147 | } | |
1148 | ||
1149 | *ndp = ndparent; | |
1150 | *ndw = ndwatch; | |
1151 | ||
1152 | return 0; | |
1153 | } | |
1154 | ||
1155 | /* Release resources used for watch path information. */ | |
1156 | static void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw) | |
1157 | { | |
1158 | if (ndp) { | |
1d957f9b | 1159 | path_put(&ndp->path); |
f368c07d AG |
1160 | kfree(ndp); |
1161 | } | |
1162 | if (ndw) { | |
1d957f9b | 1163 | path_put(&ndw->path); |
f368c07d AG |
1164 | kfree(ndw); |
1165 | } | |
1166 | } | |
1167 | ||
1168 | /* Associate the given rule with an existing parent inotify_watch. | |
1169 | * Caller must hold audit_filter_mutex. */ | |
1170 | static void audit_add_to_parent(struct audit_krule *krule, | |
1171 | struct audit_parent *parent) | |
1172 | { | |
1173 | struct audit_watch *w, *watch = krule->watch; | |
1174 | int watch_found = 0; | |
1175 | ||
1176 | list_for_each_entry(w, &parent->watches, wlist) { | |
1177 | if (strcmp(watch->path, w->path)) | |
1178 | continue; | |
1179 | ||
1180 | watch_found = 1; | |
1181 | ||
1182 | /* put krule's and initial refs to temporary watch */ | |
1183 | audit_put_watch(watch); | |
1184 | audit_put_watch(watch); | |
1185 | ||
1186 | audit_get_watch(w); | |
1187 | krule->watch = watch = w; | |
1188 | break; | |
1189 | } | |
1190 | ||
1191 | if (!watch_found) { | |
1192 | get_inotify_watch(&parent->wdata); | |
1193 | watch->parent = parent; | |
1194 | ||
1195 | list_add(&watch->wlist, &parent->watches); | |
1196 | } | |
1197 | list_add(&krule->rlist, &watch->rules); | |
1198 | } | |
1199 | ||
1200 | /* Find a matching watch entry, or add this one. | |
1201 | * Caller must hold audit_filter_mutex. */ | |
1202 | static int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, | |
1203 | struct nameidata *ndw) | |
1204 | { | |
1205 | struct audit_watch *watch = krule->watch; | |
1206 | struct inotify_watch *i_watch; | |
1207 | struct audit_parent *parent; | |
1208 | int ret = 0; | |
1209 | ||
1210 | /* update watch filter fields */ | |
1211 | if (ndw) { | |
4ac91378 JB |
1212 | watch->dev = ndw->path.dentry->d_inode->i_sb->s_dev; |
1213 | watch->ino = ndw->path.dentry->d_inode->i_ino; | |
f368c07d AG |
1214 | } |
1215 | ||
1216 | /* The audit_filter_mutex must not be held during inotify calls because | |
1217 | * we hold it during inotify event callback processing. If an existing | |
1218 | * inotify watch is found, inotify_find_watch() grabs a reference before | |
1219 | * returning. | |
1220 | */ | |
1221 | mutex_unlock(&audit_filter_mutex); | |
1222 | ||
4ac91378 JB |
1223 | if (inotify_find_watch(audit_ih, ndp->path.dentry->d_inode, |
1224 | &i_watch) < 0) { | |
f368c07d AG |
1225 | parent = audit_init_parent(ndp); |
1226 | if (IS_ERR(parent)) { | |
1227 | /* caller expects mutex locked */ | |
1228 | mutex_lock(&audit_filter_mutex); | |
1229 | return PTR_ERR(parent); | |
1230 | } | |
1231 | } else | |
1232 | parent = container_of(i_watch, struct audit_parent, wdata); | |
1233 | ||
1234 | mutex_lock(&audit_filter_mutex); | |
1235 | ||
1236 | /* parent was moved before we took audit_filter_mutex */ | |
1237 | if (parent->flags & AUDIT_PARENT_INVALID) | |
1238 | ret = -ENOENT; | |
1239 | else | |
1240 | audit_add_to_parent(krule, parent); | |
1241 | ||
1242 | /* match get in audit_init_parent or inotify_find_watch */ | |
1243 | put_inotify_watch(&parent->wdata); | |
1244 | return ret; | |
1245 | } | |
1246 | ||
1247 | /* Add rule to given filterlist if not a duplicate. */ | |
93315ed6 | 1248 | static inline int audit_add_rule(struct audit_entry *entry, |
f368c07d | 1249 | struct list_head *list) |
fe7752ba | 1250 | { |
93315ed6 | 1251 | struct audit_entry *e; |
f368c07d AG |
1252 | struct audit_field *inode_f = entry->rule.inode_f; |
1253 | struct audit_watch *watch = entry->rule.watch; | |
74c3cbe3 | 1254 | struct audit_tree *tree = entry->rule.tree; |
6f686d3d JG |
1255 | struct nameidata *ndp = NULL, *ndw = NULL; |
1256 | int h, err; | |
471a5c7c AV |
1257 | #ifdef CONFIG_AUDITSYSCALL |
1258 | int dont_count = 0; | |
1259 | ||
1260 | /* If either of these, don't count towards total */ | |
1261 | if (entry->rule.listnr == AUDIT_FILTER_USER || | |
1262 | entry->rule.listnr == AUDIT_FILTER_TYPE) | |
1263 | dont_count = 1; | |
1264 | #endif | |
f368c07d AG |
1265 | |
1266 | if (inode_f) { | |
1267 | h = audit_hash_ino(inode_f->val); | |
1268 | list = &audit_inode_hash[h]; | |
1269 | } | |
1270 | ||
1271 | mutex_lock(&audit_filter_mutex); | |
1272 | e = audit_find_rule(entry, list); | |
1273 | mutex_unlock(&audit_filter_mutex); | |
1274 | if (e) { | |
1275 | err = -EEXIST; | |
74c3cbe3 AV |
1276 | /* normally audit_add_tree_rule() will free it on failure */ |
1277 | if (tree) | |
1278 | audit_put_tree(tree); | |
f368c07d AG |
1279 | goto error; |
1280 | } | |
fe7752ba | 1281 | |
f368c07d AG |
1282 | /* Avoid calling path_lookup under audit_filter_mutex. */ |
1283 | if (watch) { | |
1284 | err = audit_get_nd(watch->path, &ndp, &ndw); | |
1285 | if (err) | |
1286 | goto error; | |
f368c07d AG |
1287 | } |
1288 | ||
1289 | mutex_lock(&audit_filter_mutex); | |
1290 | if (watch) { | |
1291 | /* audit_filter_mutex is dropped and re-taken during this call */ | |
1292 | err = audit_add_watch(&entry->rule, ndp, ndw); | |
1293 | if (err) { | |
1294 | mutex_unlock(&audit_filter_mutex); | |
1295 | goto error; | |
1296 | } | |
1297 | h = audit_hash_ino((u32)watch->ino); | |
1298 | list = &audit_inode_hash[h]; | |
fe7752ba | 1299 | } |
74c3cbe3 AV |
1300 | if (tree) { |
1301 | err = audit_add_tree_rule(&entry->rule); | |
1302 | if (err) { | |
1303 | mutex_unlock(&audit_filter_mutex); | |
1304 | goto error; | |
1305 | } | |
1306 | } | |
fe7752ba | 1307 | |
fe7752ba | 1308 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
fe7752ba | 1309 | list_add_rcu(&entry->list, list); |
6a2bceec | 1310 | entry->rule.flags &= ~AUDIT_FILTER_PREPEND; |
fe7752ba DW |
1311 | } else { |
1312 | list_add_tail_rcu(&entry->list, list); | |
1313 | } | |
471a5c7c AV |
1314 | #ifdef CONFIG_AUDITSYSCALL |
1315 | if (!dont_count) | |
1316 | audit_n_rules++; | |
e54dc243 AG |
1317 | |
1318 | if (!audit_match_signal(entry)) | |
1319 | audit_signals++; | |
471a5c7c | 1320 | #endif |
f368c07d | 1321 | mutex_unlock(&audit_filter_mutex); |
fe7752ba | 1322 | |
6f686d3d | 1323 | audit_put_nd(ndp, ndw); /* NULL args OK */ |
f368c07d AG |
1324 | return 0; |
1325 | ||
1326 | error: | |
6f686d3d | 1327 | audit_put_nd(ndp, ndw); /* NULL args OK */ |
f368c07d AG |
1328 | if (watch) |
1329 | audit_put_watch(watch); /* tmp watch, matches initial get */ | |
1330 | return err; | |
fe7752ba DW |
1331 | } |
1332 | ||
f368c07d | 1333 | /* Remove an existing rule from filterlist. */ |
93315ed6 | 1334 | static inline int audit_del_rule(struct audit_entry *entry, |
fe7752ba DW |
1335 | struct list_head *list) |
1336 | { | |
1337 | struct audit_entry *e; | |
f368c07d AG |
1338 | struct audit_field *inode_f = entry->rule.inode_f; |
1339 | struct audit_watch *watch, *tmp_watch = entry->rule.watch; | |
74c3cbe3 | 1340 | struct audit_tree *tree = entry->rule.tree; |
f368c07d AG |
1341 | LIST_HEAD(inotify_list); |
1342 | int h, ret = 0; | |
471a5c7c AV |
1343 | #ifdef CONFIG_AUDITSYSCALL |
1344 | int dont_count = 0; | |
1345 | ||
1346 | /* If either of these, don't count towards total */ | |
1347 | if (entry->rule.listnr == AUDIT_FILTER_USER || | |
1348 | entry->rule.listnr == AUDIT_FILTER_TYPE) | |
1349 | dont_count = 1; | |
1350 | #endif | |
f368c07d AG |
1351 | |
1352 | if (inode_f) { | |
1353 | h = audit_hash_ino(inode_f->val); | |
1354 | list = &audit_inode_hash[h]; | |
1355 | } | |
fe7752ba | 1356 | |
f368c07d AG |
1357 | mutex_lock(&audit_filter_mutex); |
1358 | e = audit_find_rule(entry, list); | |
1359 | if (!e) { | |
1360 | mutex_unlock(&audit_filter_mutex); | |
1361 | ret = -ENOENT; | |
1362 | goto out; | |
1363 | } | |
1364 | ||
1365 | watch = e->rule.watch; | |
1366 | if (watch) { | |
1367 | struct audit_parent *parent = watch->parent; | |
1368 | ||
1369 | list_del(&e->rule.rlist); | |
1370 | ||
1371 | if (list_empty(&watch->rules)) { | |
1372 | audit_remove_watch(watch); | |
1373 | ||
1374 | if (list_empty(&parent->watches)) { | |
1375 | /* Put parent on the inotify un-registration | |
1376 | * list. Grab a reference before releasing | |
1377 | * audit_filter_mutex, to be released in | |
1378 | * audit_inotify_unregister(). */ | |
1379 | list_add(&parent->ilist, &inotify_list); | |
1380 | get_inotify_watch(&parent->wdata); | |
1381 | } | |
fe7752ba DW |
1382 | } |
1383 | } | |
f368c07d | 1384 | |
74c3cbe3 AV |
1385 | if (e->rule.tree) |
1386 | audit_remove_tree_rule(&e->rule); | |
1387 | ||
f368c07d AG |
1388 | list_del_rcu(&e->list); |
1389 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
1390 | ||
471a5c7c AV |
1391 | #ifdef CONFIG_AUDITSYSCALL |
1392 | if (!dont_count) | |
1393 | audit_n_rules--; | |
e54dc243 AG |
1394 | |
1395 | if (!audit_match_signal(entry)) | |
1396 | audit_signals--; | |
471a5c7c | 1397 | #endif |
f368c07d AG |
1398 | mutex_unlock(&audit_filter_mutex); |
1399 | ||
1400 | if (!list_empty(&inotify_list)) | |
1401 | audit_inotify_unregister(&inotify_list); | |
1402 | ||
1403 | out: | |
1404 | if (tmp_watch) | |
1405 | audit_put_watch(tmp_watch); /* match initial get */ | |
74c3cbe3 AV |
1406 | if (tree) |
1407 | audit_put_tree(tree); /* that's the temporary one */ | |
f368c07d AG |
1408 | |
1409 | return ret; | |
fe7752ba DW |
1410 | } |
1411 | ||
93315ed6 AG |
1412 | /* List rules using struct audit_rule. Exists for backward |
1413 | * compatibility with userspace. */ | |
9044e6bc | 1414 | static void audit_list(int pid, int seq, struct sk_buff_head *q) |
fe7752ba | 1415 | { |
9044e6bc | 1416 | struct sk_buff *skb; |
fe7752ba DW |
1417 | struct audit_entry *entry; |
1418 | int i; | |
1419 | ||
f368c07d AG |
1420 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1421 | * iterator to sync with list writers. */ | |
fe7752ba | 1422 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
93315ed6 AG |
1423 | list_for_each_entry(entry, &audit_filter_list[i], list) { |
1424 | struct audit_rule *rule; | |
1425 | ||
1426 | rule = audit_krule_to_rule(&entry->rule); | |
1427 | if (unlikely(!rule)) | |
1428 | break; | |
9044e6bc | 1429 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, |
93315ed6 | 1430 | rule, sizeof(*rule)); |
9044e6bc AV |
1431 | if (skb) |
1432 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1433 | kfree(rule); |
1434 | } | |
fe7752ba | 1435 | } |
f368c07d AG |
1436 | for (i = 0; i < AUDIT_INODE_BUCKETS; i++) { |
1437 | list_for_each_entry(entry, &audit_inode_hash[i], list) { | |
1438 | struct audit_rule *rule; | |
1439 | ||
1440 | rule = audit_krule_to_rule(&entry->rule); | |
1441 | if (unlikely(!rule)) | |
1442 | break; | |
1443 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, | |
1444 | rule, sizeof(*rule)); | |
1445 | if (skb) | |
1446 | skb_queue_tail(q, skb); | |
1447 | kfree(rule); | |
1448 | } | |
1449 | } | |
9044e6bc AV |
1450 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0); |
1451 | if (skb) | |
1452 | skb_queue_tail(q, skb); | |
fe7752ba DW |
1453 | } |
1454 | ||
93315ed6 | 1455 | /* List rules using struct audit_rule_data. */ |
9044e6bc | 1456 | static void audit_list_rules(int pid, int seq, struct sk_buff_head *q) |
93315ed6 | 1457 | { |
9044e6bc | 1458 | struct sk_buff *skb; |
93315ed6 AG |
1459 | struct audit_entry *e; |
1460 | int i; | |
1461 | ||
f368c07d AG |
1462 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1463 | * iterator to sync with list writers. */ | |
93315ed6 AG |
1464 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
1465 | list_for_each_entry(e, &audit_filter_list[i], list) { | |
1466 | struct audit_rule_data *data; | |
1467 | ||
1468 | data = audit_krule_to_data(&e->rule); | |
1469 | if (unlikely(!data)) | |
1470 | break; | |
9044e6bc | 1471 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, |
f368c07d AG |
1472 | data, sizeof(*data) + data->buflen); |
1473 | if (skb) | |
1474 | skb_queue_tail(q, skb); | |
1475 | kfree(data); | |
1476 | } | |
1477 | } | |
1478 | for (i=0; i< AUDIT_INODE_BUCKETS; i++) { | |
1479 | list_for_each_entry(e, &audit_inode_hash[i], list) { | |
1480 | struct audit_rule_data *data; | |
1481 | ||
1482 | data = audit_krule_to_data(&e->rule); | |
1483 | if (unlikely(!data)) | |
1484 | break; | |
1485 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, | |
1486 | data, sizeof(*data) + data->buflen); | |
9044e6bc AV |
1487 | if (skb) |
1488 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1489 | kfree(data); |
1490 | } | |
1491 | } | |
9044e6bc AV |
1492 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); |
1493 | if (skb) | |
1494 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1495 | } |
1496 | ||
5adc8a6a | 1497 | /* Log rule additions and removals */ |
2532386f EP |
1498 | static void audit_log_rule_change(uid_t loginuid, u32 sessionid, u32 sid, |
1499 | char *action, struct audit_krule *rule, | |
1500 | int res) | |
5adc8a6a AG |
1501 | { |
1502 | struct audit_buffer *ab; | |
1503 | ||
1a6b9f23 EP |
1504 | if (!audit_enabled) |
1505 | return; | |
1506 | ||
5adc8a6a AG |
1507 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
1508 | if (!ab) | |
1509 | return; | |
2532386f | 1510 | audit_log_format(ab, "auid=%u ses=%u", loginuid, sessionid); |
5adc8a6a AG |
1511 | if (sid) { |
1512 | char *ctx = NULL; | |
1513 | u32 len; | |
2a862b32 | 1514 | if (security_secid_to_secctx(sid, &ctx, &len)) |
5adc8a6a | 1515 | audit_log_format(ab, " ssid=%u", sid); |
2a862b32 | 1516 | else { |
5adc8a6a | 1517 | audit_log_format(ab, " subj=%s", ctx); |
2a862b32 AD |
1518 | security_release_secctx(ctx, len); |
1519 | } | |
5adc8a6a | 1520 | } |
a17b4ad7 | 1521 | audit_log_format(ab, " op=%s rule key=", action); |
5adc8a6a AG |
1522 | if (rule->filterkey) |
1523 | audit_log_untrustedstring(ab, rule->filterkey); | |
1524 | else | |
1525 | audit_log_format(ab, "(null)"); | |
1526 | audit_log_format(ab, " list=%d res=%d", rule->listnr, res); | |
1527 | audit_log_end(ab); | |
1528 | } | |
1529 | ||
fe7752ba DW |
1530 | /** |
1531 | * audit_receive_filter - apply all rules to the specified message type | |
1532 | * @type: audit message type | |
1533 | * @pid: target pid for netlink audit messages | |
1534 | * @uid: target uid for netlink audit messages | |
1535 | * @seq: netlink audit message sequence (serial) number | |
1536 | * @data: payload data | |
93315ed6 | 1537 | * @datasz: size of payload data |
fe7752ba | 1538 | * @loginuid: loginuid of sender |
ce29b682 | 1539 | * @sid: SE Linux Security ID of sender |
fe7752ba DW |
1540 | */ |
1541 | int audit_receive_filter(int type, int pid, int uid, int seq, void *data, | |
2532386f | 1542 | size_t datasz, uid_t loginuid, u32 sessionid, u32 sid) |
fe7752ba DW |
1543 | { |
1544 | struct task_struct *tsk; | |
9044e6bc | 1545 | struct audit_netlink_list *dest; |
93315ed6 AG |
1546 | int err = 0; |
1547 | struct audit_entry *entry; | |
fe7752ba DW |
1548 | |
1549 | switch (type) { | |
1550 | case AUDIT_LIST: | |
93315ed6 | 1551 | case AUDIT_LIST_RULES: |
fe7752ba DW |
1552 | /* We can't just spew out the rules here because we might fill |
1553 | * the available socket buffer space and deadlock waiting for | |
1554 | * auditctl to read from it... which isn't ever going to | |
1555 | * happen if we're actually running in the context of auditctl | |
1556 | * trying to _send_ the stuff */ | |
9ce34218 | 1557 | |
9044e6bc | 1558 | dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); |
fe7752ba DW |
1559 | if (!dest) |
1560 | return -ENOMEM; | |
9044e6bc AV |
1561 | dest->pid = pid; |
1562 | skb_queue_head_init(&dest->q); | |
fe7752ba | 1563 | |
f368c07d | 1564 | mutex_lock(&audit_filter_mutex); |
93315ed6 | 1565 | if (type == AUDIT_LIST) |
9044e6bc | 1566 | audit_list(pid, seq, &dest->q); |
93315ed6 | 1567 | else |
9044e6bc | 1568 | audit_list_rules(pid, seq, &dest->q); |
f368c07d | 1569 | mutex_unlock(&audit_filter_mutex); |
9044e6bc AV |
1570 | |
1571 | tsk = kthread_run(audit_send_list, dest, "audit_send_list"); | |
fe7752ba | 1572 | if (IS_ERR(tsk)) { |
9044e6bc | 1573 | skb_queue_purge(&dest->q); |
fe7752ba DW |
1574 | kfree(dest); |
1575 | err = PTR_ERR(tsk); | |
1576 | } | |
1577 | break; | |
1578 | case AUDIT_ADD: | |
93315ed6 AG |
1579 | case AUDIT_ADD_RULE: |
1580 | if (type == AUDIT_ADD) | |
1581 | entry = audit_rule_to_entry(data); | |
1582 | else | |
1583 | entry = audit_data_to_entry(data, datasz); | |
1584 | if (IS_ERR(entry)) | |
1585 | return PTR_ERR(entry); | |
1586 | ||
1587 | err = audit_add_rule(entry, | |
1588 | &audit_filter_list[entry->rule.listnr]); | |
2532386f EP |
1589 | audit_log_rule_change(loginuid, sessionid, sid, "add", |
1590 | &entry->rule, !err); | |
5d330108 SG |
1591 | |
1592 | if (err) | |
93315ed6 | 1593 | audit_free_rule(entry); |
fe7752ba DW |
1594 | break; |
1595 | case AUDIT_DEL: | |
93315ed6 AG |
1596 | case AUDIT_DEL_RULE: |
1597 | if (type == AUDIT_DEL) | |
1598 | entry = audit_rule_to_entry(data); | |
1599 | else | |
1600 | entry = audit_data_to_entry(data, datasz); | |
1601 | if (IS_ERR(entry)) | |
1602 | return PTR_ERR(entry); | |
1603 | ||
1604 | err = audit_del_rule(entry, | |
1605 | &audit_filter_list[entry->rule.listnr]); | |
2532386f EP |
1606 | audit_log_rule_change(loginuid, sessionid, sid, "remove", |
1607 | &entry->rule, !err); | |
5d330108 | 1608 | |
93315ed6 | 1609 | audit_free_rule(entry); |
fe7752ba DW |
1610 | break; |
1611 | default: | |
1612 | return -EINVAL; | |
1613 | } | |
1614 | ||
1615 | return err; | |
1616 | } | |
1617 | ||
1618 | int audit_comparator(const u32 left, const u32 op, const u32 right) | |
1619 | { | |
1620 | switch (op) { | |
1621 | case AUDIT_EQUAL: | |
1622 | return (left == right); | |
1623 | case AUDIT_NOT_EQUAL: | |
1624 | return (left != right); | |
1625 | case AUDIT_LESS_THAN: | |
1626 | return (left < right); | |
1627 | case AUDIT_LESS_THAN_OR_EQUAL: | |
1628 | return (left <= right); | |
1629 | case AUDIT_GREATER_THAN: | |
1630 | return (left > right); | |
1631 | case AUDIT_GREATER_THAN_OR_EQUAL: | |
1632 | return (left >= right); | |
74f2345b EP |
1633 | case AUDIT_BIT_MASK: |
1634 | return (left & right); | |
1635 | case AUDIT_BIT_TEST: | |
1636 | return ((left & right) == right); | |
fe7752ba | 1637 | } |
d9d9ec6e DK |
1638 | BUG(); |
1639 | return 0; | |
fe7752ba DW |
1640 | } |
1641 | ||
f368c07d AG |
1642 | /* Compare given dentry name with last component in given path, |
1643 | * return of 0 indicates a match. */ | |
9c937dcc AG |
1644 | int audit_compare_dname_path(const char *dname, const char *path, |
1645 | int *dirlen) | |
f368c07d AG |
1646 | { |
1647 | int dlen, plen; | |
1648 | const char *p; | |
1649 | ||
1650 | if (!dname || !path) | |
1651 | return 1; | |
1652 | ||
1653 | dlen = strlen(dname); | |
1654 | plen = strlen(path); | |
1655 | if (plen < dlen) | |
1656 | return 1; | |
1657 | ||
1658 | /* disregard trailing slashes */ | |
1659 | p = path + plen - 1; | |
1660 | while ((*p == '/') && (p > path)) | |
1661 | p--; | |
1662 | ||
1663 | /* find last path component */ | |
1664 | p = p - dlen + 1; | |
1665 | if (p < path) | |
1666 | return 1; | |
1667 | else if (p > path) { | |
1668 | if (*--p != '/') | |
1669 | return 1; | |
1670 | else | |
1671 | p++; | |
1672 | } | |
fe7752ba | 1673 | |
9c937dcc AG |
1674 | /* return length of path's directory component */ |
1675 | if (dirlen) | |
1676 | *dirlen = p - path; | |
f368c07d AG |
1677 | return strncmp(p, dname, dlen); |
1678 | } | |
fe7752ba DW |
1679 | |
1680 | static int audit_filter_user_rules(struct netlink_skb_parms *cb, | |
93315ed6 | 1681 | struct audit_krule *rule, |
fe7752ba DW |
1682 | enum audit_state *state) |
1683 | { | |
1684 | int i; | |
1685 | ||
1686 | for (i = 0; i < rule->field_count; i++) { | |
93315ed6 | 1687 | struct audit_field *f = &rule->fields[i]; |
fe7752ba DW |
1688 | int result = 0; |
1689 | ||
93315ed6 | 1690 | switch (f->type) { |
fe7752ba | 1691 | case AUDIT_PID: |
93315ed6 | 1692 | result = audit_comparator(cb->creds.pid, f->op, f->val); |
fe7752ba DW |
1693 | break; |
1694 | case AUDIT_UID: | |
93315ed6 | 1695 | result = audit_comparator(cb->creds.uid, f->op, f->val); |
fe7752ba DW |
1696 | break; |
1697 | case AUDIT_GID: | |
93315ed6 | 1698 | result = audit_comparator(cb->creds.gid, f->op, f->val); |
fe7752ba DW |
1699 | break; |
1700 | case AUDIT_LOGINUID: | |
93315ed6 | 1701 | result = audit_comparator(cb->loginuid, f->op, f->val); |
fe7752ba DW |
1702 | break; |
1703 | } | |
1704 | ||
1705 | if (!result) | |
1706 | return 0; | |
1707 | } | |
1708 | switch (rule->action) { | |
1709 | case AUDIT_NEVER: *state = AUDIT_DISABLED; break; | |
fe7752ba DW |
1710 | case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; |
1711 | } | |
1712 | return 1; | |
1713 | } | |
1714 | ||
1715 | int audit_filter_user(struct netlink_skb_parms *cb, int type) | |
1716 | { | |
11f57ced | 1717 | enum audit_state state = AUDIT_DISABLED; |
fe7752ba | 1718 | struct audit_entry *e; |
fe7752ba DW |
1719 | int ret = 1; |
1720 | ||
1721 | rcu_read_lock(); | |
1722 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { | |
1723 | if (audit_filter_user_rules(cb, &e->rule, &state)) { | |
1724 | if (state == AUDIT_DISABLED) | |
1725 | ret = 0; | |
1726 | break; | |
1727 | } | |
1728 | } | |
1729 | rcu_read_unlock(); | |
1730 | ||
1731 | return ret; /* Audit by default */ | |
1732 | } | |
1733 | ||
1734 | int audit_filter_type(int type) | |
1735 | { | |
1736 | struct audit_entry *e; | |
1737 | int result = 0; | |
9ce34218 | 1738 | |
fe7752ba DW |
1739 | rcu_read_lock(); |
1740 | if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE])) | |
1741 | goto unlock_and_return; | |
1742 | ||
1743 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE], | |
1744 | list) { | |
fe7752ba | 1745 | int i; |
93315ed6 AG |
1746 | for (i = 0; i < e->rule.field_count; i++) { |
1747 | struct audit_field *f = &e->rule.fields[i]; | |
1748 | if (f->type == AUDIT_MSGTYPE) { | |
1749 | result = audit_comparator(type, f->op, f->val); | |
fe7752ba DW |
1750 | if (!result) |
1751 | break; | |
1752 | } | |
1753 | } | |
1754 | if (result) | |
1755 | goto unlock_and_return; | |
1756 | } | |
1757 | unlock_and_return: | |
1758 | rcu_read_unlock(); | |
1759 | return result; | |
1760 | } | |
3dc7e315 | 1761 | |
04305e4a | 1762 | /* This function will re-initialize the lsm_rule field of all applicable rules. |
d7a96f3a | 1763 | * It will traverse the filter lists serarching for rules that contain LSM |
3dc7e315 | 1764 | * specific filter fields. When such a rule is found, it is copied, the |
d7a96f3a | 1765 | * LSM field is re-initialized, and the old rule is replaced with the |
3dc7e315 | 1766 | * updated rule. */ |
d7a96f3a | 1767 | int audit_update_lsm_rules(void) |
3dc7e315 DG |
1768 | { |
1769 | struct audit_entry *entry, *n, *nentry; | |
f368c07d | 1770 | struct audit_watch *watch; |
74c3cbe3 | 1771 | struct audit_tree *tree; |
3dc7e315 DG |
1772 | int i, err = 0; |
1773 | ||
f368c07d AG |
1774 | /* audit_filter_mutex synchronizes the writers */ |
1775 | mutex_lock(&audit_filter_mutex); | |
3dc7e315 DG |
1776 | |
1777 | for (i = 0; i < AUDIT_NR_FILTERS; i++) { | |
1778 | list_for_each_entry_safe(entry, n, &audit_filter_list[i], list) { | |
d7a96f3a | 1779 | if (!security_audit_rule_known(&entry->rule)) |
3dc7e315 DG |
1780 | continue; |
1781 | ||
f368c07d | 1782 | watch = entry->rule.watch; |
74c3cbe3 | 1783 | tree = entry->rule.tree; |
f368c07d | 1784 | nentry = audit_dupe_rule(&entry->rule, watch); |
3dc7e315 DG |
1785 | if (unlikely(IS_ERR(nentry))) { |
1786 | /* save the first error encountered for the | |
1787 | * return value */ | |
1788 | if (!err) | |
1789 | err = PTR_ERR(nentry); | |
d7a96f3a | 1790 | audit_panic("error updating LSM filters"); |
f368c07d AG |
1791 | if (watch) |
1792 | list_del(&entry->rule.rlist); | |
3dc7e315 DG |
1793 | list_del_rcu(&entry->list); |
1794 | } else { | |
f368c07d AG |
1795 | if (watch) { |
1796 | list_add(&nentry->rule.rlist, | |
1797 | &watch->rules); | |
1798 | list_del(&entry->rule.rlist); | |
74c3cbe3 AV |
1799 | } else if (tree) |
1800 | list_replace_init(&entry->rule.rlist, | |
1801 | &nentry->rule.rlist); | |
3dc7e315 DG |
1802 | list_replace_rcu(&entry->list, &nentry->list); |
1803 | } | |
1804 | call_rcu(&entry->rcu, audit_free_rule_rcu); | |
1805 | } | |
1806 | } | |
1807 | ||
f368c07d | 1808 | mutex_unlock(&audit_filter_mutex); |
3dc7e315 DG |
1809 | |
1810 | return err; | |
1811 | } | |
f368c07d AG |
1812 | |
1813 | /* Update watch data in audit rules based on inotify events. */ | |
1814 | void audit_handle_ievent(struct inotify_watch *i_watch, u32 wd, u32 mask, | |
1815 | u32 cookie, const char *dname, struct inode *inode) | |
1816 | { | |
1817 | struct audit_parent *parent; | |
1818 | ||
1819 | parent = container_of(i_watch, struct audit_parent, wdata); | |
1820 | ||
1821 | if (mask & (IN_CREATE|IN_MOVED_TO) && inode) | |
1822 | audit_update_watch(parent, dname, inode->i_sb->s_dev, | |
1823 | inode->i_ino, 0); | |
1824 | else if (mask & (IN_DELETE|IN_MOVED_FROM)) | |
1825 | audit_update_watch(parent, dname, (dev_t)-1, (unsigned long)-1, 1); | |
1826 | /* inotify automatically removes the watch and sends IN_IGNORED */ | |
1827 | else if (mask & (IN_DELETE_SELF|IN_UNMOUNT)) | |
1828 | audit_remove_parent_watches(parent); | |
1829 | /* inotify does not remove the watch, so remove it manually */ | |
1830 | else if(mask & IN_MOVE_SELF) { | |
1831 | audit_remove_parent_watches(parent); | |
1832 | inotify_remove_watch_locked(audit_ih, i_watch); | |
1833 | } else if (mask & IN_IGNORED) | |
1834 | put_inotify_watch(i_watch); | |
1835 | } |