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 | }; | |
e45aa212 AV |
89 | static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = { |
90 | LIST_HEAD_INIT(audit_rules_list[0]), | |
91 | LIST_HEAD_INIT(audit_rules_list[1]), | |
92 | LIST_HEAD_INIT(audit_rules_list[2]), | |
93 | LIST_HEAD_INIT(audit_rules_list[3]), | |
94 | LIST_HEAD_INIT(audit_rules_list[4]), | |
95 | LIST_HEAD_INIT(audit_rules_list[5]), | |
96 | }; | |
fe7752ba | 97 | |
74c3cbe3 | 98 | DEFINE_MUTEX(audit_filter_mutex); |
f368c07d | 99 | |
f368c07d AG |
100 | /* Inotify events we care about. */ |
101 | #define AUDIT_IN_WATCH IN_MOVE|IN_CREATE|IN_DELETE|IN_DELETE_SELF|IN_MOVE_SELF | |
102 | ||
103 | void audit_free_parent(struct inotify_watch *i_watch) | |
104 | { | |
105 | struct audit_parent *parent; | |
106 | ||
107 | parent = container_of(i_watch, struct audit_parent, wdata); | |
108 | WARN_ON(!list_empty(&parent->watches)); | |
109 | kfree(parent); | |
110 | } | |
111 | ||
112 | static inline void audit_get_watch(struct audit_watch *watch) | |
113 | { | |
114 | atomic_inc(&watch->count); | |
115 | } | |
116 | ||
117 | static void audit_put_watch(struct audit_watch *watch) | |
118 | { | |
119 | if (atomic_dec_and_test(&watch->count)) { | |
120 | WARN_ON(watch->parent); | |
121 | WARN_ON(!list_empty(&watch->rules)); | |
122 | kfree(watch->path); | |
123 | kfree(watch); | |
124 | } | |
125 | } | |
126 | ||
127 | static void audit_remove_watch(struct audit_watch *watch) | |
128 | { | |
129 | list_del(&watch->wlist); | |
130 | put_inotify_watch(&watch->parent->wdata); | |
131 | watch->parent = NULL; | |
132 | audit_put_watch(watch); /* match initial get */ | |
133 | } | |
134 | ||
93315ed6 | 135 | static inline void audit_free_rule(struct audit_entry *e) |
fe7752ba | 136 | { |
3dc7e315 | 137 | int i; |
f368c07d AG |
138 | |
139 | /* some rules don't have associated watches */ | |
140 | if (e->rule.watch) | |
141 | audit_put_watch(e->rule.watch); | |
3dc7e315 DG |
142 | if (e->rule.fields) |
143 | for (i = 0; i < e->rule.field_count; i++) { | |
144 | struct audit_field *f = &e->rule.fields[i]; | |
04305e4a AD |
145 | kfree(f->lsm_str); |
146 | security_audit_rule_free(f->lsm_rule); | |
3dc7e315 | 147 | } |
93315ed6 | 148 | kfree(e->rule.fields); |
5adc8a6a | 149 | kfree(e->rule.filterkey); |
93315ed6 AG |
150 | kfree(e); |
151 | } | |
152 | ||
74c3cbe3 | 153 | void audit_free_rule_rcu(struct rcu_head *head) |
93315ed6 AG |
154 | { |
155 | struct audit_entry *e = container_of(head, struct audit_entry, rcu); | |
156 | audit_free_rule(e); | |
157 | } | |
158 | ||
f368c07d AG |
159 | /* Initialize a parent watch entry. */ |
160 | static struct audit_parent *audit_init_parent(struct nameidata *ndp) | |
161 | { | |
162 | struct audit_parent *parent; | |
163 | s32 wd; | |
164 | ||
165 | parent = kzalloc(sizeof(*parent), GFP_KERNEL); | |
166 | if (unlikely(!parent)) | |
167 | return ERR_PTR(-ENOMEM); | |
168 | ||
169 | INIT_LIST_HEAD(&parent->watches); | |
170 | parent->flags = 0; | |
171 | ||
172 | inotify_init_watch(&parent->wdata); | |
173 | /* grab a ref so inotify watch hangs around until we take audit_filter_mutex */ | |
174 | get_inotify_watch(&parent->wdata); | |
4ac91378 JB |
175 | wd = inotify_add_watch(audit_ih, &parent->wdata, |
176 | ndp->path.dentry->d_inode, AUDIT_IN_WATCH); | |
f368c07d AG |
177 | if (wd < 0) { |
178 | audit_free_parent(&parent->wdata); | |
179 | return ERR_PTR(wd); | |
180 | } | |
181 | ||
182 | return parent; | |
183 | } | |
184 | ||
185 | /* Initialize a watch entry. */ | |
186 | static struct audit_watch *audit_init_watch(char *path) | |
187 | { | |
188 | struct audit_watch *watch; | |
189 | ||
190 | watch = kzalloc(sizeof(*watch), GFP_KERNEL); | |
191 | if (unlikely(!watch)) | |
192 | return ERR_PTR(-ENOMEM); | |
193 | ||
194 | INIT_LIST_HEAD(&watch->rules); | |
195 | atomic_set(&watch->count, 1); | |
196 | watch->path = path; | |
197 | watch->dev = (dev_t)-1; | |
198 | watch->ino = (unsigned long)-1; | |
199 | ||
200 | return watch; | |
201 | } | |
202 | ||
3dc7e315 DG |
203 | /* Initialize an audit filterlist entry. */ |
204 | static inline struct audit_entry *audit_init_entry(u32 field_count) | |
205 | { | |
206 | struct audit_entry *entry; | |
207 | struct audit_field *fields; | |
208 | ||
209 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
210 | if (unlikely(!entry)) | |
211 | return NULL; | |
212 | ||
213 | fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL); | |
214 | if (unlikely(!fields)) { | |
215 | kfree(entry); | |
216 | return NULL; | |
217 | } | |
218 | entry->rule.fields = fields; | |
219 | ||
220 | return entry; | |
221 | } | |
222 | ||
93315ed6 AG |
223 | /* Unpack a filter field's string representation from user-space |
224 | * buffer. */ | |
74c3cbe3 | 225 | char *audit_unpack_string(void **bufp, size_t *remain, size_t len) |
93315ed6 AG |
226 | { |
227 | char *str; | |
228 | ||
229 | if (!*bufp || (len == 0) || (len > *remain)) | |
230 | return ERR_PTR(-EINVAL); | |
231 | ||
232 | /* Of the currently implemented string fields, PATH_MAX | |
233 | * defines the longest valid length. | |
234 | */ | |
235 | if (len > PATH_MAX) | |
236 | return ERR_PTR(-ENAMETOOLONG); | |
237 | ||
238 | str = kmalloc(len + 1, GFP_KERNEL); | |
239 | if (unlikely(!str)) | |
240 | return ERR_PTR(-ENOMEM); | |
241 | ||
242 | memcpy(str, *bufp, len); | |
243 | str[len] = 0; | |
244 | *bufp += len; | |
245 | *remain -= len; | |
246 | ||
247 | return str; | |
248 | } | |
249 | ||
f368c07d AG |
250 | /* Translate an inode field to kernel respresentation. */ |
251 | static inline int audit_to_inode(struct audit_krule *krule, | |
252 | struct audit_field *f) | |
253 | { | |
254 | if (krule->listnr != AUDIT_FILTER_EXIT || | |
74c3cbe3 | 255 | krule->watch || krule->inode_f || krule->tree) |
f368c07d AG |
256 | return -EINVAL; |
257 | ||
258 | krule->inode_f = f; | |
259 | return 0; | |
260 | } | |
261 | ||
262 | /* Translate a watch string to kernel respresentation. */ | |
263 | static int audit_to_watch(struct audit_krule *krule, char *path, int len, | |
264 | u32 op) | |
265 | { | |
266 | struct audit_watch *watch; | |
267 | ||
268 | if (!audit_ih) | |
269 | return -EOPNOTSUPP; | |
270 | ||
271 | if (path[0] != '/' || path[len-1] == '/' || | |
272 | krule->listnr != AUDIT_FILTER_EXIT || | |
273 | op & ~AUDIT_EQUAL || | |
74c3cbe3 | 274 | krule->inode_f || krule->watch || krule->tree) |
f368c07d AG |
275 | return -EINVAL; |
276 | ||
277 | watch = audit_init_watch(path); | |
801678c5 | 278 | if (IS_ERR(watch)) |
f368c07d AG |
279 | return PTR_ERR(watch); |
280 | ||
281 | audit_get_watch(watch); | |
282 | krule->watch = watch; | |
283 | ||
284 | return 0; | |
285 | } | |
286 | ||
b915543b AV |
287 | static __u32 *classes[AUDIT_SYSCALL_CLASSES]; |
288 | ||
289 | int __init audit_register_class(int class, unsigned *list) | |
290 | { | |
291 | __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL); | |
292 | if (!p) | |
293 | return -ENOMEM; | |
294 | while (*list != ~0U) { | |
295 | unsigned n = *list++; | |
296 | if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { | |
297 | kfree(p); | |
298 | return -EINVAL; | |
299 | } | |
300 | p[AUDIT_WORD(n)] |= AUDIT_BIT(n); | |
301 | } | |
302 | if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { | |
303 | kfree(p); | |
304 | return -EINVAL; | |
305 | } | |
306 | classes[class] = p; | |
307 | return 0; | |
308 | } | |
309 | ||
55669bfa AV |
310 | int audit_match_class(int class, unsigned syscall) |
311 | { | |
c926e4f4 | 312 | if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32)) |
55669bfa AV |
313 | return 0; |
314 | if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) | |
315 | return 0; | |
316 | return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); | |
317 | } | |
318 | ||
327b9eeb | 319 | #ifdef CONFIG_AUDITSYSCALL |
e54dc243 AG |
320 | static inline int audit_match_class_bits(int class, u32 *mask) |
321 | { | |
322 | int i; | |
323 | ||
324 | if (classes[class]) { | |
325 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
326 | if (mask[i] & classes[class][i]) | |
327 | return 0; | |
328 | } | |
329 | return 1; | |
330 | } | |
331 | ||
332 | static int audit_match_signal(struct audit_entry *entry) | |
333 | { | |
334 | struct audit_field *arch = entry->rule.arch_f; | |
335 | ||
336 | if (!arch) { | |
337 | /* When arch is unspecified, we must check both masks on biarch | |
338 | * as syscall number alone is ambiguous. */ | |
339 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
340 | entry->rule.mask) && | |
341 | audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
342 | entry->rule.mask)); | |
343 | } | |
344 | ||
345 | switch(audit_classify_arch(arch->val)) { | |
346 | case 0: /* native */ | |
347 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
348 | entry->rule.mask)); | |
349 | case 1: /* 32bit on biarch */ | |
350 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
351 | entry->rule.mask)); | |
352 | default: | |
353 | return 1; | |
354 | } | |
355 | } | |
327b9eeb | 356 | #endif |
e54dc243 | 357 | |
93315ed6 AG |
358 | /* Common user-space to kernel rule translation. */ |
359 | static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) | |
360 | { | |
361 | unsigned listnr; | |
362 | struct audit_entry *entry; | |
93315ed6 AG |
363 | int i, err; |
364 | ||
365 | err = -EINVAL; | |
366 | listnr = rule->flags & ~AUDIT_FILTER_PREPEND; | |
367 | switch(listnr) { | |
368 | default: | |
369 | goto exit_err; | |
370 | case AUDIT_FILTER_USER: | |
371 | case AUDIT_FILTER_TYPE: | |
372 | #ifdef CONFIG_AUDITSYSCALL | |
373 | case AUDIT_FILTER_ENTRY: | |
374 | case AUDIT_FILTER_EXIT: | |
375 | case AUDIT_FILTER_TASK: | |
376 | #endif | |
377 | ; | |
378 | } | |
014149cc AV |
379 | if (unlikely(rule->action == AUDIT_POSSIBLE)) { |
380 | printk(KERN_ERR "AUDIT_POSSIBLE is deprecated\n"); | |
381 | goto exit_err; | |
382 | } | |
383 | if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS) | |
93315ed6 AG |
384 | goto exit_err; |
385 | if (rule->field_count > AUDIT_MAX_FIELDS) | |
386 | goto exit_err; | |
387 | ||
388 | err = -ENOMEM; | |
3dc7e315 DG |
389 | entry = audit_init_entry(rule->field_count); |
390 | if (!entry) | |
93315ed6 | 391 | goto exit_err; |
93315ed6 AG |
392 | |
393 | entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND; | |
394 | entry->rule.listnr = listnr; | |
395 | entry->rule.action = rule->action; | |
396 | entry->rule.field_count = rule->field_count; | |
93315ed6 AG |
397 | |
398 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
399 | entry->rule.mask[i] = rule->mask[i]; | |
400 | ||
b915543b AV |
401 | for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { |
402 | int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; | |
403 | __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; | |
404 | __u32 *class; | |
405 | ||
406 | if (!(*p & AUDIT_BIT(bit))) | |
407 | continue; | |
408 | *p &= ~AUDIT_BIT(bit); | |
409 | class = classes[i]; | |
410 | if (class) { | |
411 | int j; | |
412 | for (j = 0; j < AUDIT_BITMASK_SIZE; j++) | |
413 | entry->rule.mask[j] |= class[j]; | |
414 | } | |
415 | } | |
416 | ||
93315ed6 AG |
417 | return entry; |
418 | ||
419 | exit_err: | |
420 | return ERR_PTR(err); | |
421 | } | |
422 | ||
423 | /* Translate struct audit_rule to kernel's rule respresentation. | |
424 | * Exists for backward compatibility with userspace. */ | |
425 | static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) | |
426 | { | |
427 | struct audit_entry *entry; | |
7719e437 | 428 | struct audit_field *ino_f; |
93315ed6 | 429 | int err = 0; |
fe7752ba DW |
430 | int i; |
431 | ||
93315ed6 AG |
432 | entry = audit_to_entry_common(rule); |
433 | if (IS_ERR(entry)) | |
434 | goto exit_nofree; | |
435 | ||
436 | for (i = 0; i < rule->field_count; i++) { | |
437 | struct audit_field *f = &entry->rule.fields[i]; | |
438 | ||
93315ed6 AG |
439 | f->op = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS); |
440 | f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS); | |
441 | f->val = rule->values[i]; | |
442 | ||
f368c07d | 443 | err = -EINVAL; |
f368c07d | 444 | switch(f->type) { |
0a73dccc | 445 | default: |
3dc7e315 | 446 | goto exit_free; |
0a73dccc AV |
447 | case AUDIT_PID: |
448 | case AUDIT_UID: | |
449 | case AUDIT_EUID: | |
450 | case AUDIT_SUID: | |
451 | case AUDIT_FSUID: | |
452 | case AUDIT_GID: | |
453 | case AUDIT_EGID: | |
454 | case AUDIT_SGID: | |
455 | case AUDIT_FSGID: | |
456 | case AUDIT_LOGINUID: | |
457 | case AUDIT_PERS: | |
0a73dccc | 458 | case AUDIT_MSGTYPE: |
3b33ac31 | 459 | case AUDIT_PPID: |
0a73dccc AV |
460 | case AUDIT_DEVMAJOR: |
461 | case AUDIT_DEVMINOR: | |
462 | case AUDIT_EXIT: | |
463 | case AUDIT_SUCCESS: | |
74f2345b EP |
464 | /* bit ops are only useful on syscall args */ |
465 | if (f->op == AUDIT_BIT_MASK || | |
466 | f->op == AUDIT_BIT_TEST) { | |
467 | err = -EINVAL; | |
468 | goto exit_free; | |
469 | } | |
470 | break; | |
0a73dccc AV |
471 | case AUDIT_ARG0: |
472 | case AUDIT_ARG1: | |
473 | case AUDIT_ARG2: | |
474 | case AUDIT_ARG3: | |
475 | break; | |
4b8a311b EP |
476 | /* arch is only allowed to be = or != */ |
477 | case AUDIT_ARCH: | |
478 | if ((f->op != AUDIT_NOT_EQUAL) && (f->op != AUDIT_EQUAL) | |
479 | && (f->op != AUDIT_NEGATE) && (f->op)) { | |
480 | err = -EINVAL; | |
481 | goto exit_free; | |
482 | } | |
e54dc243 | 483 | entry->rule.arch_f = f; |
4b8a311b | 484 | break; |
55669bfa AV |
485 | case AUDIT_PERM: |
486 | if (f->val & ~15) | |
487 | goto exit_free; | |
488 | break; | |
8b67dca9 AV |
489 | case AUDIT_FILETYPE: |
490 | if ((f->val & ~S_IFMT) > S_IFMT) | |
491 | goto exit_free; | |
492 | break; | |
f368c07d AG |
493 | case AUDIT_INODE: |
494 | err = audit_to_inode(&entry->rule, f); | |
495 | if (err) | |
496 | goto exit_free; | |
497 | break; | |
3dc7e315 DG |
498 | } |
499 | ||
93315ed6 | 500 | entry->rule.vers_ops = (f->op & AUDIT_OPERATORS) ? 2 : 1; |
d9d9ec6e DK |
501 | |
502 | /* Support for legacy operators where | |
503 | * AUDIT_NEGATE bit signifies != and otherwise assumes == */ | |
93315ed6 | 504 | if (f->op & AUDIT_NEGATE) |
d9d9ec6e DK |
505 | f->op = AUDIT_NOT_EQUAL; |
506 | else if (!f->op) | |
507 | f->op = AUDIT_EQUAL; | |
508 | else if (f->op == AUDIT_OPERATORS) { | |
509 | err = -EINVAL; | |
510 | goto exit_free; | |
511 | } | |
fe7752ba | 512 | } |
93315ed6 | 513 | |
7719e437 HH |
514 | ino_f = entry->rule.inode_f; |
515 | if (ino_f) { | |
516 | switch(ino_f->op) { | |
f368c07d AG |
517 | case AUDIT_NOT_EQUAL: |
518 | entry->rule.inode_f = NULL; | |
519 | case AUDIT_EQUAL: | |
520 | break; | |
521 | default: | |
5422e01a | 522 | err = -EINVAL; |
f368c07d AG |
523 | goto exit_free; |
524 | } | |
525 | } | |
526 | ||
93315ed6 AG |
527 | exit_nofree: |
528 | return entry; | |
529 | ||
530 | exit_free: | |
531 | audit_free_rule(entry); | |
532 | return ERR_PTR(err); | |
fe7752ba DW |
533 | } |
534 | ||
93315ed6 AG |
535 | /* Translate struct audit_rule_data to kernel's rule respresentation. */ |
536 | static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, | |
537 | size_t datasz) | |
fe7752ba | 538 | { |
93315ed6 AG |
539 | int err = 0; |
540 | struct audit_entry *entry; | |
7719e437 | 541 | struct audit_field *ino_f; |
93315ed6 | 542 | void *bufp; |
3dc7e315 | 543 | size_t remain = datasz - sizeof(struct audit_rule_data); |
fe7752ba | 544 | int i; |
3dc7e315 | 545 | char *str; |
fe7752ba | 546 | |
93315ed6 AG |
547 | entry = audit_to_entry_common((struct audit_rule *)data); |
548 | if (IS_ERR(entry)) | |
549 | goto exit_nofree; | |
fe7752ba | 550 | |
93315ed6 AG |
551 | bufp = data->buf; |
552 | entry->rule.vers_ops = 2; | |
553 | for (i = 0; i < data->field_count; i++) { | |
554 | struct audit_field *f = &entry->rule.fields[i]; | |
555 | ||
556 | err = -EINVAL; | |
557 | if (!(data->fieldflags[i] & AUDIT_OPERATORS) || | |
558 | data->fieldflags[i] & ~AUDIT_OPERATORS) | |
559 | goto exit_free; | |
560 | ||
561 | f->op = data->fieldflags[i] & AUDIT_OPERATORS; | |
562 | f->type = data->fields[i]; | |
3dc7e315 | 563 | f->val = data->values[i]; |
04305e4a AD |
564 | f->lsm_str = NULL; |
565 | f->lsm_rule = NULL; | |
93315ed6 | 566 | switch(f->type) { |
0a73dccc AV |
567 | case AUDIT_PID: |
568 | case AUDIT_UID: | |
569 | case AUDIT_EUID: | |
570 | case AUDIT_SUID: | |
571 | case AUDIT_FSUID: | |
572 | case AUDIT_GID: | |
573 | case AUDIT_EGID: | |
574 | case AUDIT_SGID: | |
575 | case AUDIT_FSGID: | |
576 | case AUDIT_LOGINUID: | |
577 | case AUDIT_PERS: | |
0a73dccc AV |
578 | case AUDIT_MSGTYPE: |
579 | case AUDIT_PPID: | |
580 | case AUDIT_DEVMAJOR: | |
581 | case AUDIT_DEVMINOR: | |
582 | case AUDIT_EXIT: | |
583 | case AUDIT_SUCCESS: | |
584 | case AUDIT_ARG0: | |
585 | case AUDIT_ARG1: | |
586 | case AUDIT_ARG2: | |
587 | case AUDIT_ARG3: | |
588 | break; | |
e54dc243 AG |
589 | case AUDIT_ARCH: |
590 | entry->rule.arch_f = f; | |
591 | break; | |
3a6b9f85 DG |
592 | case AUDIT_SUBJ_USER: |
593 | case AUDIT_SUBJ_ROLE: | |
594 | case AUDIT_SUBJ_TYPE: | |
595 | case AUDIT_SUBJ_SEN: | |
596 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
597 | case AUDIT_OBJ_USER: |
598 | case AUDIT_OBJ_ROLE: | |
599 | case AUDIT_OBJ_TYPE: | |
600 | case AUDIT_OBJ_LEV_LOW: | |
601 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
602 | str = audit_unpack_string(&bufp, &remain, f->val); |
603 | if (IS_ERR(str)) | |
604 | goto exit_free; | |
605 | entry->rule.buflen += f->val; | |
606 | ||
d7a96f3a | 607 | err = security_audit_rule_init(f->type, f->op, str, |
04305e4a | 608 | (void **)&f->lsm_rule); |
3dc7e315 DG |
609 | /* Keep currently invalid fields around in case they |
610 | * become valid after a policy reload. */ | |
611 | if (err == -EINVAL) { | |
d7a96f3a | 612 | printk(KERN_WARNING "audit rule for LSM " |
3dc7e315 DG |
613 | "\'%s\' is invalid\n", str); |
614 | err = 0; | |
615 | } | |
616 | if (err) { | |
617 | kfree(str); | |
618 | goto exit_free; | |
619 | } else | |
04305e4a | 620 | f->lsm_str = str; |
3dc7e315 | 621 | break; |
f368c07d AG |
622 | case AUDIT_WATCH: |
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_to_watch(&entry->rule, str, f->val, f->op); | |
629 | if (err) { | |
630 | kfree(str); | |
631 | goto exit_free; | |
632 | } | |
633 | break; | |
74c3cbe3 AV |
634 | case AUDIT_DIR: |
635 | str = audit_unpack_string(&bufp, &remain, f->val); | |
636 | if (IS_ERR(str)) | |
637 | goto exit_free; | |
638 | entry->rule.buflen += f->val; | |
639 | ||
640 | err = audit_make_tree(&entry->rule, str, f->op); | |
641 | kfree(str); | |
642 | if (err) | |
643 | goto exit_free; | |
644 | break; | |
f368c07d AG |
645 | case AUDIT_INODE: |
646 | err = audit_to_inode(&entry->rule, f); | |
647 | if (err) | |
648 | goto exit_free; | |
649 | break; | |
5adc8a6a AG |
650 | case AUDIT_FILTERKEY: |
651 | err = -EINVAL; | |
652 | if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN) | |
653 | goto exit_free; | |
654 | str = audit_unpack_string(&bufp, &remain, f->val); | |
655 | if (IS_ERR(str)) | |
656 | goto exit_free; | |
657 | entry->rule.buflen += f->val; | |
658 | entry->rule.filterkey = str; | |
659 | break; | |
55669bfa AV |
660 | case AUDIT_PERM: |
661 | if (f->val & ~15) | |
662 | goto exit_free; | |
663 | break; | |
8b67dca9 AV |
664 | case AUDIT_FILETYPE: |
665 | if ((f->val & ~S_IFMT) > S_IFMT) | |
666 | goto exit_free; | |
667 | break; | |
0a73dccc AV |
668 | default: |
669 | goto exit_free; | |
f368c07d AG |
670 | } |
671 | } | |
672 | ||
7719e437 HH |
673 | ino_f = entry->rule.inode_f; |
674 | if (ino_f) { | |
675 | switch(ino_f->op) { | |
f368c07d AG |
676 | case AUDIT_NOT_EQUAL: |
677 | entry->rule.inode_f = NULL; | |
678 | case AUDIT_EQUAL: | |
679 | break; | |
680 | default: | |
5422e01a | 681 | err = -EINVAL; |
f368c07d | 682 | goto exit_free; |
93315ed6 AG |
683 | } |
684 | } | |
685 | ||
686 | exit_nofree: | |
687 | return entry; | |
688 | ||
689 | exit_free: | |
690 | audit_free_rule(entry); | |
691 | return ERR_PTR(err); | |
692 | } | |
693 | ||
694 | /* Pack a filter field's string representation into data block. */ | |
74c3cbe3 | 695 | static inline size_t audit_pack_string(void **bufp, const char *str) |
93315ed6 AG |
696 | { |
697 | size_t len = strlen(str); | |
698 | ||
699 | memcpy(*bufp, str, len); | |
700 | *bufp += len; | |
701 | ||
702 | return len; | |
703 | } | |
704 | ||
705 | /* Translate kernel rule respresentation to struct audit_rule. | |
706 | * Exists for backward compatibility with userspace. */ | |
707 | static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule) | |
708 | { | |
709 | struct audit_rule *rule; | |
710 | int i; | |
711 | ||
4668edc3 | 712 | rule = kzalloc(sizeof(*rule), GFP_KERNEL); |
93315ed6 | 713 | if (unlikely(!rule)) |
0a3b483e | 714 | return NULL; |
93315ed6 AG |
715 | |
716 | rule->flags = krule->flags | krule->listnr; | |
717 | rule->action = krule->action; | |
718 | rule->field_count = krule->field_count; | |
719 | for (i = 0; i < rule->field_count; i++) { | |
720 | rule->values[i] = krule->fields[i].val; | |
721 | rule->fields[i] = krule->fields[i].type; | |
722 | ||
723 | if (krule->vers_ops == 1) { | |
724 | if (krule->fields[i].op & AUDIT_NOT_EQUAL) | |
725 | rule->fields[i] |= AUDIT_NEGATE; | |
726 | } else { | |
727 | rule->fields[i] |= krule->fields[i].op; | |
728 | } | |
729 | } | |
730 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i]; | |
731 | ||
732 | return rule; | |
733 | } | |
fe7752ba | 734 | |
93315ed6 AG |
735 | /* Translate kernel rule respresentation to struct audit_rule_data. */ |
736 | static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) | |
737 | { | |
738 | struct audit_rule_data *data; | |
739 | void *bufp; | |
740 | int i; | |
741 | ||
742 | data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); | |
743 | if (unlikely(!data)) | |
0a3b483e | 744 | return NULL; |
93315ed6 AG |
745 | memset(data, 0, sizeof(*data)); |
746 | ||
747 | data->flags = krule->flags | krule->listnr; | |
748 | data->action = krule->action; | |
749 | data->field_count = krule->field_count; | |
750 | bufp = data->buf; | |
751 | for (i = 0; i < data->field_count; i++) { | |
752 | struct audit_field *f = &krule->fields[i]; | |
753 | ||
754 | data->fields[i] = f->type; | |
755 | data->fieldflags[i] = f->op; | |
756 | switch(f->type) { | |
3a6b9f85 DG |
757 | case AUDIT_SUBJ_USER: |
758 | case AUDIT_SUBJ_ROLE: | |
759 | case AUDIT_SUBJ_TYPE: | |
760 | case AUDIT_SUBJ_SEN: | |
761 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
762 | case AUDIT_OBJ_USER: |
763 | case AUDIT_OBJ_ROLE: | |
764 | case AUDIT_OBJ_TYPE: | |
765 | case AUDIT_OBJ_LEV_LOW: | |
766 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 | 767 | data->buflen += data->values[i] = |
04305e4a | 768 | audit_pack_string(&bufp, f->lsm_str); |
3dc7e315 | 769 | break; |
f368c07d AG |
770 | case AUDIT_WATCH: |
771 | data->buflen += data->values[i] = | |
772 | audit_pack_string(&bufp, krule->watch->path); | |
773 | break; | |
74c3cbe3 AV |
774 | case AUDIT_DIR: |
775 | data->buflen += data->values[i] = | |
776 | audit_pack_string(&bufp, | |
777 | audit_tree_path(krule->tree)); | |
778 | break; | |
5adc8a6a AG |
779 | case AUDIT_FILTERKEY: |
780 | data->buflen += data->values[i] = | |
781 | audit_pack_string(&bufp, krule->filterkey); | |
782 | break; | |
93315ed6 AG |
783 | default: |
784 | data->values[i] = f->val; | |
785 | } | |
786 | } | |
787 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i]; | |
788 | ||
789 | return data; | |
790 | } | |
791 | ||
792 | /* Compare two rules in kernel format. Considered success if rules | |
793 | * don't match. */ | |
794 | static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) | |
795 | { | |
796 | int i; | |
797 | ||
798 | if (a->flags != b->flags || | |
799 | a->listnr != b->listnr || | |
800 | a->action != b->action || | |
801 | a->field_count != b->field_count) | |
fe7752ba DW |
802 | return 1; |
803 | ||
804 | for (i = 0; i < a->field_count; i++) { | |
93315ed6 AG |
805 | if (a->fields[i].type != b->fields[i].type || |
806 | a->fields[i].op != b->fields[i].op) | |
fe7752ba | 807 | return 1; |
93315ed6 AG |
808 | |
809 | switch(a->fields[i].type) { | |
3a6b9f85 DG |
810 | case AUDIT_SUBJ_USER: |
811 | case AUDIT_SUBJ_ROLE: | |
812 | case AUDIT_SUBJ_TYPE: | |
813 | case AUDIT_SUBJ_SEN: | |
814 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
815 | case AUDIT_OBJ_USER: |
816 | case AUDIT_OBJ_ROLE: | |
817 | case AUDIT_OBJ_TYPE: | |
818 | case AUDIT_OBJ_LEV_LOW: | |
819 | case AUDIT_OBJ_LEV_HIGH: | |
04305e4a | 820 | if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str)) |
3dc7e315 DG |
821 | return 1; |
822 | break; | |
f368c07d AG |
823 | case AUDIT_WATCH: |
824 | if (strcmp(a->watch->path, b->watch->path)) | |
825 | return 1; | |
826 | break; | |
74c3cbe3 AV |
827 | case AUDIT_DIR: |
828 | if (strcmp(audit_tree_path(a->tree), | |
829 | audit_tree_path(b->tree))) | |
830 | return 1; | |
831 | break; | |
5adc8a6a AG |
832 | case AUDIT_FILTERKEY: |
833 | /* both filterkeys exist based on above type compare */ | |
834 | if (strcmp(a->filterkey, b->filterkey)) | |
835 | return 1; | |
836 | break; | |
93315ed6 AG |
837 | default: |
838 | if (a->fields[i].val != b->fields[i].val) | |
839 | return 1; | |
840 | } | |
fe7752ba DW |
841 | } |
842 | ||
843 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
844 | if (a->mask[i] != b->mask[i]) | |
845 | return 1; | |
846 | ||
847 | return 0; | |
848 | } | |
849 | ||
f368c07d AG |
850 | /* Duplicate the given audit watch. The new watch's rules list is initialized |
851 | * to an empty list and wlist is undefined. */ | |
852 | static struct audit_watch *audit_dupe_watch(struct audit_watch *old) | |
853 | { | |
854 | char *path; | |
855 | struct audit_watch *new; | |
856 | ||
857 | path = kstrdup(old->path, GFP_KERNEL); | |
858 | if (unlikely(!path)) | |
859 | return ERR_PTR(-ENOMEM); | |
860 | ||
861 | new = audit_init_watch(path); | |
801678c5 | 862 | if (IS_ERR(new)) { |
f368c07d AG |
863 | kfree(path); |
864 | goto out; | |
865 | } | |
866 | ||
867 | new->dev = old->dev; | |
868 | new->ino = old->ino; | |
869 | get_inotify_watch(&old->parent->wdata); | |
870 | new->parent = old->parent; | |
871 | ||
872 | out: | |
873 | return new; | |
874 | } | |
875 | ||
04305e4a | 876 | /* Duplicate LSM field information. The lsm_rule is opaque, so must be |
3dc7e315 | 877 | * re-initialized. */ |
d7a96f3a | 878 | static inline int audit_dupe_lsm_field(struct audit_field *df, |
3dc7e315 DG |
879 | struct audit_field *sf) |
880 | { | |
881 | int ret = 0; | |
04305e4a | 882 | char *lsm_str; |
3dc7e315 | 883 | |
04305e4a AD |
884 | /* our own copy of lsm_str */ |
885 | lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL); | |
886 | if (unlikely(!lsm_str)) | |
3e1fbd12 | 887 | return -ENOMEM; |
04305e4a | 888 | df->lsm_str = lsm_str; |
3dc7e315 | 889 | |
04305e4a AD |
890 | /* our own (refreshed) copy of lsm_rule */ |
891 | ret = security_audit_rule_init(df->type, df->op, df->lsm_str, | |
892 | (void **)&df->lsm_rule); | |
3dc7e315 DG |
893 | /* Keep currently invalid fields around in case they |
894 | * become valid after a policy reload. */ | |
895 | if (ret == -EINVAL) { | |
d7a96f3a | 896 | printk(KERN_WARNING "audit rule for LSM \'%s\' is " |
04305e4a | 897 | "invalid\n", df->lsm_str); |
3dc7e315 DG |
898 | ret = 0; |
899 | } | |
900 | ||
901 | return ret; | |
902 | } | |
903 | ||
904 | /* Duplicate an audit rule. This will be a deep copy with the exception | |
d7a96f3a | 905 | * of the watch - that pointer is carried over. The LSM specific fields |
3dc7e315 | 906 | * will be updated in the copy. The point is to be able to replace the old |
f368c07d AG |
907 | * rule with the new rule in the filterlist, then free the old rule. |
908 | * The rlist element is undefined; list manipulations are handled apart from | |
909 | * the initial copy. */ | |
910 | static struct audit_entry *audit_dupe_rule(struct audit_krule *old, | |
911 | struct audit_watch *watch) | |
3dc7e315 DG |
912 | { |
913 | u32 fcount = old->field_count; | |
914 | struct audit_entry *entry; | |
915 | struct audit_krule *new; | |
5adc8a6a | 916 | char *fk; |
3dc7e315 DG |
917 | int i, err = 0; |
918 | ||
919 | entry = audit_init_entry(fcount); | |
920 | if (unlikely(!entry)) | |
921 | return ERR_PTR(-ENOMEM); | |
922 | ||
923 | new = &entry->rule; | |
924 | new->vers_ops = old->vers_ops; | |
925 | new->flags = old->flags; | |
926 | new->listnr = old->listnr; | |
927 | new->action = old->action; | |
928 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
929 | new->mask[i] = old->mask[i]; | |
0590b933 | 930 | new->prio = old->prio; |
3dc7e315 | 931 | new->buflen = old->buflen; |
f368c07d AG |
932 | new->inode_f = old->inode_f; |
933 | new->watch = NULL; | |
3dc7e315 | 934 | new->field_count = old->field_count; |
74c3cbe3 AV |
935 | /* |
936 | * note that we are OK with not refcounting here; audit_match_tree() | |
937 | * never dereferences tree and we can't get false positives there | |
938 | * since we'd have to have rule gone from the list *and* removed | |
939 | * before the chunks found by lookup had been allocated, i.e. before | |
940 | * the beginning of list scan. | |
941 | */ | |
942 | new->tree = old->tree; | |
3dc7e315 DG |
943 | memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount); |
944 | ||
04305e4a | 945 | /* deep copy this information, updating the lsm_rule fields, because |
3dc7e315 DG |
946 | * the originals will all be freed when the old rule is freed. */ |
947 | for (i = 0; i < fcount; i++) { | |
948 | switch (new->fields[i].type) { | |
3a6b9f85 DG |
949 | case AUDIT_SUBJ_USER: |
950 | case AUDIT_SUBJ_ROLE: | |
951 | case AUDIT_SUBJ_TYPE: | |
952 | case AUDIT_SUBJ_SEN: | |
953 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
954 | case AUDIT_OBJ_USER: |
955 | case AUDIT_OBJ_ROLE: | |
956 | case AUDIT_OBJ_TYPE: | |
957 | case AUDIT_OBJ_LEV_LOW: | |
958 | case AUDIT_OBJ_LEV_HIGH: | |
d7a96f3a | 959 | err = audit_dupe_lsm_field(&new->fields[i], |
3dc7e315 | 960 | &old->fields[i]); |
5adc8a6a AG |
961 | break; |
962 | case AUDIT_FILTERKEY: | |
963 | fk = kstrdup(old->filterkey, GFP_KERNEL); | |
964 | if (unlikely(!fk)) | |
965 | err = -ENOMEM; | |
966 | else | |
967 | new->filterkey = fk; | |
3dc7e315 DG |
968 | } |
969 | if (err) { | |
970 | audit_free_rule(entry); | |
971 | return ERR_PTR(err); | |
972 | } | |
973 | } | |
974 | ||
f368c07d AG |
975 | if (watch) { |
976 | audit_get_watch(watch); | |
977 | new->watch = watch; | |
978 | } | |
979 | ||
3dc7e315 DG |
980 | return entry; |
981 | } | |
982 | ||
f368c07d AG |
983 | /* Update inode info in audit rules based on filesystem event. */ |
984 | static void audit_update_watch(struct audit_parent *parent, | |
985 | const char *dname, dev_t dev, | |
986 | unsigned long ino, unsigned invalidating) | |
987 | { | |
988 | struct audit_watch *owatch, *nwatch, *nextw; | |
989 | struct audit_krule *r, *nextr; | |
990 | struct audit_entry *oentry, *nentry; | |
f368c07d AG |
991 | |
992 | mutex_lock(&audit_filter_mutex); | |
993 | list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) { | |
9c937dcc | 994 | if (audit_compare_dname_path(dname, owatch->path, NULL)) |
f368c07d AG |
995 | continue; |
996 | ||
997 | /* If the update involves invalidating rules, do the inode-based | |
998 | * filtering now, so we don't omit records. */ | |
0590b933 AV |
999 | if (invalidating && current->audit_context) |
1000 | audit_filter_inodes(current, current->audit_context); | |
f368c07d AG |
1001 | |
1002 | nwatch = audit_dupe_watch(owatch); | |
801678c5 | 1003 | if (IS_ERR(nwatch)) { |
f368c07d AG |
1004 | mutex_unlock(&audit_filter_mutex); |
1005 | audit_panic("error updating watch, skipping"); | |
1006 | return; | |
1007 | } | |
1008 | nwatch->dev = dev; | |
1009 | nwatch->ino = ino; | |
1010 | ||
1011 | list_for_each_entry_safe(r, nextr, &owatch->rules, rlist) { | |
1012 | ||
1013 | oentry = container_of(r, struct audit_entry, rule); | |
1014 | list_del(&oentry->rule.rlist); | |
1015 | list_del_rcu(&oentry->list); | |
1016 | ||
1017 | nentry = audit_dupe_rule(&oentry->rule, nwatch); | |
e45aa212 AV |
1018 | if (IS_ERR(nentry)) { |
1019 | list_del(&oentry->rule.list); | |
f368c07d | 1020 | audit_panic("error updating watch, removing"); |
e45aa212 | 1021 | } else { |
f368c07d AG |
1022 | int h = audit_hash_ino((u32)ino); |
1023 | list_add(&nentry->rule.rlist, &nwatch->rules); | |
1024 | list_add_rcu(&nentry->list, &audit_inode_hash[h]); | |
e45aa212 AV |
1025 | list_replace(&oentry->rule.list, |
1026 | &nentry->rule.list); | |
f368c07d AG |
1027 | } |
1028 | ||
1029 | call_rcu(&oentry->rcu, audit_free_rule_rcu); | |
1030 | } | |
1031 | ||
1a6b9f23 EP |
1032 | if (audit_enabled) { |
1033 | struct audit_buffer *ab; | |
1034 | ab = audit_log_start(NULL, GFP_KERNEL, | |
1035 | AUDIT_CONFIG_CHANGE); | |
036bbf76 | 1036 | audit_log_format(ab, "auid=%u ses=%u", |
1037 | audit_get_loginuid(current), | |
1038 | audit_get_sessionid(current)); | |
1a6b9f23 | 1039 | audit_log_format(ab, |
036bbf76 | 1040 | " op=updated rules specifying path="); |
1a6b9f23 EP |
1041 | audit_log_untrustedstring(ab, owatch->path); |
1042 | audit_log_format(ab, " with dev=%u ino=%lu\n", | |
1043 | dev, ino); | |
1044 | audit_log_format(ab, " list=%d res=1", r->listnr); | |
1045 | audit_log_end(ab); | |
1046 | } | |
f368c07d AG |
1047 | audit_remove_watch(owatch); |
1048 | goto add_watch_to_parent; /* event applies to a single watch */ | |
1049 | } | |
1050 | mutex_unlock(&audit_filter_mutex); | |
1051 | return; | |
1052 | ||
1053 | add_watch_to_parent: | |
1054 | list_add(&nwatch->wlist, &parent->watches); | |
1055 | mutex_unlock(&audit_filter_mutex); | |
1056 | return; | |
1057 | } | |
1058 | ||
1059 | /* Remove all watches & rules associated with a parent that is going away. */ | |
1060 | static void audit_remove_parent_watches(struct audit_parent *parent) | |
1061 | { | |
1062 | struct audit_watch *w, *nextw; | |
1063 | struct audit_krule *r, *nextr; | |
1064 | struct audit_entry *e; | |
1065 | ||
1066 | mutex_lock(&audit_filter_mutex); | |
1067 | parent->flags |= AUDIT_PARENT_INVALID; | |
1068 | list_for_each_entry_safe(w, nextw, &parent->watches, wlist) { | |
1069 | list_for_each_entry_safe(r, nextr, &w->rules, rlist) { | |
1070 | e = container_of(r, struct audit_entry, rule); | |
1a6b9f23 EP |
1071 | if (audit_enabled) { |
1072 | struct audit_buffer *ab; | |
1073 | ab = audit_log_start(NULL, GFP_KERNEL, | |
1074 | AUDIT_CONFIG_CHANGE); | |
036bbf76 | 1075 | audit_log_format(ab, "auid=%u ses=%u", |
1076 | audit_get_loginuid(current), | |
1077 | audit_get_sessionid(current)); | |
1078 | audit_log_format(ab, " op=remove rule path="); | |
1a6b9f23 EP |
1079 | audit_log_untrustedstring(ab, w->path); |
1080 | if (r->filterkey) { | |
1081 | audit_log_format(ab, " key="); | |
1082 | audit_log_untrustedstring(ab, | |
1083 | r->filterkey); | |
1084 | } else | |
1085 | audit_log_format(ab, " key=(null)"); | |
1086 | audit_log_format(ab, " list=%d res=1", | |
1087 | r->listnr); | |
1088 | audit_log_end(ab); | |
1089 | } | |
f368c07d | 1090 | list_del(&r->rlist); |
e45aa212 | 1091 | list_del(&r->list); |
f368c07d AG |
1092 | list_del_rcu(&e->list); |
1093 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
f368c07d AG |
1094 | } |
1095 | audit_remove_watch(w); | |
1096 | } | |
1097 | mutex_unlock(&audit_filter_mutex); | |
1098 | } | |
1099 | ||
1100 | /* Unregister inotify watches for parents on in_list. | |
1101 | * Generates an IN_IGNORED event. */ | |
1102 | static void audit_inotify_unregister(struct list_head *in_list) | |
1103 | { | |
1104 | struct audit_parent *p, *n; | |
1105 | ||
1106 | list_for_each_entry_safe(p, n, in_list, ilist) { | |
1107 | list_del(&p->ilist); | |
1108 | inotify_rm_watch(audit_ih, &p->wdata); | |
8f7b0ba1 AV |
1109 | /* the unpin matching the pin in audit_do_del_rule() */ |
1110 | unpin_inotify_watch(&p->wdata); | |
f368c07d AG |
1111 | } |
1112 | } | |
1113 | ||
1114 | /* Find an existing audit rule. | |
1115 | * Caller must hold audit_filter_mutex to prevent stale rule data. */ | |
1116 | static struct audit_entry *audit_find_rule(struct audit_entry *entry, | |
1117 | struct list_head *list) | |
1118 | { | |
1119 | struct audit_entry *e, *found = NULL; | |
1120 | int h; | |
1121 | ||
1122 | if (entry->rule.watch) { | |
1123 | /* we don't know the inode number, so must walk entire hash */ | |
1124 | for (h = 0; h < AUDIT_INODE_BUCKETS; h++) { | |
1125 | list = &audit_inode_hash[h]; | |
1126 | list_for_each_entry(e, list, list) | |
1127 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
1128 | found = e; | |
1129 | goto out; | |
1130 | } | |
1131 | } | |
1132 | goto out; | |
1133 | } | |
1134 | ||
1135 | list_for_each_entry(e, list, list) | |
1136 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
1137 | found = e; | |
1138 | goto out; | |
1139 | } | |
1140 | ||
1141 | out: | |
1142 | return found; | |
1143 | } | |
1144 | ||
1145 | /* Get path information necessary for adding watches. */ | |
1146 | static int audit_get_nd(char *path, struct nameidata **ndp, | |
1147 | struct nameidata **ndw) | |
1148 | { | |
1149 | struct nameidata *ndparent, *ndwatch; | |
1150 | int err; | |
1151 | ||
1152 | ndparent = kmalloc(sizeof(*ndparent), GFP_KERNEL); | |
1153 | if (unlikely(!ndparent)) | |
1154 | return -ENOMEM; | |
1155 | ||
1156 | ndwatch = kmalloc(sizeof(*ndwatch), GFP_KERNEL); | |
1157 | if (unlikely(!ndwatch)) { | |
1158 | kfree(ndparent); | |
1159 | return -ENOMEM; | |
1160 | } | |
1161 | ||
1162 | err = path_lookup(path, LOOKUP_PARENT, ndparent); | |
1163 | if (err) { | |
1164 | kfree(ndparent); | |
1165 | kfree(ndwatch); | |
1166 | return err; | |
1167 | } | |
1168 | ||
1169 | err = path_lookup(path, 0, ndwatch); | |
1170 | if (err) { | |
1171 | kfree(ndwatch); | |
1172 | ndwatch = NULL; | |
1173 | } | |
1174 | ||
1175 | *ndp = ndparent; | |
1176 | *ndw = ndwatch; | |
1177 | ||
1178 | return 0; | |
1179 | } | |
1180 | ||
1181 | /* Release resources used for watch path information. */ | |
1182 | static void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw) | |
1183 | { | |
1184 | if (ndp) { | |
1d957f9b | 1185 | path_put(&ndp->path); |
f368c07d AG |
1186 | kfree(ndp); |
1187 | } | |
1188 | if (ndw) { | |
1d957f9b | 1189 | path_put(&ndw->path); |
f368c07d AG |
1190 | kfree(ndw); |
1191 | } | |
1192 | } | |
1193 | ||
1194 | /* Associate the given rule with an existing parent inotify_watch. | |
1195 | * Caller must hold audit_filter_mutex. */ | |
1196 | static void audit_add_to_parent(struct audit_krule *krule, | |
1197 | struct audit_parent *parent) | |
1198 | { | |
1199 | struct audit_watch *w, *watch = krule->watch; | |
1200 | int watch_found = 0; | |
1201 | ||
1202 | list_for_each_entry(w, &parent->watches, wlist) { | |
1203 | if (strcmp(watch->path, w->path)) | |
1204 | continue; | |
1205 | ||
1206 | watch_found = 1; | |
1207 | ||
1208 | /* put krule's and initial refs to temporary watch */ | |
1209 | audit_put_watch(watch); | |
1210 | audit_put_watch(watch); | |
1211 | ||
1212 | audit_get_watch(w); | |
1213 | krule->watch = watch = w; | |
1214 | break; | |
1215 | } | |
1216 | ||
1217 | if (!watch_found) { | |
1218 | get_inotify_watch(&parent->wdata); | |
1219 | watch->parent = parent; | |
1220 | ||
1221 | list_add(&watch->wlist, &parent->watches); | |
1222 | } | |
1223 | list_add(&krule->rlist, &watch->rules); | |
1224 | } | |
1225 | ||
1226 | /* Find a matching watch entry, or add this one. | |
1227 | * Caller must hold audit_filter_mutex. */ | |
1228 | static int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, | |
1229 | struct nameidata *ndw) | |
1230 | { | |
1231 | struct audit_watch *watch = krule->watch; | |
1232 | struct inotify_watch *i_watch; | |
1233 | struct audit_parent *parent; | |
1234 | int ret = 0; | |
1235 | ||
1236 | /* update watch filter fields */ | |
1237 | if (ndw) { | |
4ac91378 JB |
1238 | watch->dev = ndw->path.dentry->d_inode->i_sb->s_dev; |
1239 | watch->ino = ndw->path.dentry->d_inode->i_ino; | |
f368c07d AG |
1240 | } |
1241 | ||
1242 | /* The audit_filter_mutex must not be held during inotify calls because | |
1243 | * we hold it during inotify event callback processing. If an existing | |
1244 | * inotify watch is found, inotify_find_watch() grabs a reference before | |
1245 | * returning. | |
1246 | */ | |
1247 | mutex_unlock(&audit_filter_mutex); | |
1248 | ||
4ac91378 JB |
1249 | if (inotify_find_watch(audit_ih, ndp->path.dentry->d_inode, |
1250 | &i_watch) < 0) { | |
f368c07d AG |
1251 | parent = audit_init_parent(ndp); |
1252 | if (IS_ERR(parent)) { | |
1253 | /* caller expects mutex locked */ | |
1254 | mutex_lock(&audit_filter_mutex); | |
1255 | return PTR_ERR(parent); | |
1256 | } | |
1257 | } else | |
1258 | parent = container_of(i_watch, struct audit_parent, wdata); | |
1259 | ||
1260 | mutex_lock(&audit_filter_mutex); | |
1261 | ||
1262 | /* parent was moved before we took audit_filter_mutex */ | |
1263 | if (parent->flags & AUDIT_PARENT_INVALID) | |
1264 | ret = -ENOENT; | |
1265 | else | |
1266 | audit_add_to_parent(krule, parent); | |
1267 | ||
1268 | /* match get in audit_init_parent or inotify_find_watch */ | |
1269 | put_inotify_watch(&parent->wdata); | |
1270 | return ret; | |
1271 | } | |
1272 | ||
0590b933 AV |
1273 | static u64 prio_low = ~0ULL/2; |
1274 | static u64 prio_high = ~0ULL/2 - 1; | |
1275 | ||
f368c07d | 1276 | /* Add rule to given filterlist if not a duplicate. */ |
93315ed6 | 1277 | static inline int audit_add_rule(struct audit_entry *entry, |
f368c07d | 1278 | struct list_head *list) |
fe7752ba | 1279 | { |
93315ed6 | 1280 | struct audit_entry *e; |
f368c07d AG |
1281 | struct audit_field *inode_f = entry->rule.inode_f; |
1282 | struct audit_watch *watch = entry->rule.watch; | |
74c3cbe3 | 1283 | struct audit_tree *tree = entry->rule.tree; |
6f686d3d JG |
1284 | struct nameidata *ndp = NULL, *ndw = NULL; |
1285 | int h, err; | |
471a5c7c AV |
1286 | #ifdef CONFIG_AUDITSYSCALL |
1287 | int dont_count = 0; | |
1288 | ||
1289 | /* If either of these, don't count towards total */ | |
1290 | if (entry->rule.listnr == AUDIT_FILTER_USER || | |
1291 | entry->rule.listnr == AUDIT_FILTER_TYPE) | |
1292 | dont_count = 1; | |
1293 | #endif | |
f368c07d AG |
1294 | |
1295 | if (inode_f) { | |
1296 | h = audit_hash_ino(inode_f->val); | |
1297 | list = &audit_inode_hash[h]; | |
1298 | } | |
1299 | ||
1300 | mutex_lock(&audit_filter_mutex); | |
1301 | e = audit_find_rule(entry, list); | |
1302 | mutex_unlock(&audit_filter_mutex); | |
1303 | if (e) { | |
1304 | err = -EEXIST; | |
74c3cbe3 AV |
1305 | /* normally audit_add_tree_rule() will free it on failure */ |
1306 | if (tree) | |
1307 | audit_put_tree(tree); | |
f368c07d AG |
1308 | goto error; |
1309 | } | |
fe7752ba | 1310 | |
f368c07d AG |
1311 | /* Avoid calling path_lookup under audit_filter_mutex. */ |
1312 | if (watch) { | |
1313 | err = audit_get_nd(watch->path, &ndp, &ndw); | |
1314 | if (err) | |
1315 | goto error; | |
f368c07d AG |
1316 | } |
1317 | ||
1318 | mutex_lock(&audit_filter_mutex); | |
1319 | if (watch) { | |
1320 | /* audit_filter_mutex is dropped and re-taken during this call */ | |
1321 | err = audit_add_watch(&entry->rule, ndp, ndw); | |
1322 | if (err) { | |
1323 | mutex_unlock(&audit_filter_mutex); | |
1324 | goto error; | |
1325 | } | |
1326 | h = audit_hash_ino((u32)watch->ino); | |
1327 | list = &audit_inode_hash[h]; | |
fe7752ba | 1328 | } |
74c3cbe3 AV |
1329 | if (tree) { |
1330 | err = audit_add_tree_rule(&entry->rule); | |
1331 | if (err) { | |
1332 | mutex_unlock(&audit_filter_mutex); | |
1333 | goto error; | |
1334 | } | |
1335 | } | |
fe7752ba | 1336 | |
0590b933 AV |
1337 | entry->rule.prio = ~0ULL; |
1338 | if (entry->rule.listnr == AUDIT_FILTER_EXIT) { | |
1339 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) | |
1340 | entry->rule.prio = ++prio_high; | |
1341 | else | |
1342 | entry->rule.prio = --prio_low; | |
1343 | } | |
1344 | ||
fe7752ba | 1345 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
e45aa212 AV |
1346 | list_add(&entry->rule.list, |
1347 | &audit_rules_list[entry->rule.listnr]); | |
fe7752ba | 1348 | list_add_rcu(&entry->list, list); |
6a2bceec | 1349 | entry->rule.flags &= ~AUDIT_FILTER_PREPEND; |
fe7752ba | 1350 | } else { |
e45aa212 AV |
1351 | list_add_tail(&entry->rule.list, |
1352 | &audit_rules_list[entry->rule.listnr]); | |
fe7752ba DW |
1353 | list_add_tail_rcu(&entry->list, list); |
1354 | } | |
471a5c7c AV |
1355 | #ifdef CONFIG_AUDITSYSCALL |
1356 | if (!dont_count) | |
1357 | audit_n_rules++; | |
e54dc243 AG |
1358 | |
1359 | if (!audit_match_signal(entry)) | |
1360 | audit_signals++; | |
471a5c7c | 1361 | #endif |
f368c07d | 1362 | mutex_unlock(&audit_filter_mutex); |
fe7752ba | 1363 | |
6f686d3d | 1364 | audit_put_nd(ndp, ndw); /* NULL args OK */ |
f368c07d AG |
1365 | return 0; |
1366 | ||
1367 | error: | |
6f686d3d | 1368 | audit_put_nd(ndp, ndw); /* NULL args OK */ |
f368c07d AG |
1369 | if (watch) |
1370 | audit_put_watch(watch); /* tmp watch, matches initial get */ | |
1371 | return err; | |
fe7752ba DW |
1372 | } |
1373 | ||
f368c07d | 1374 | /* Remove an existing rule from filterlist. */ |
93315ed6 | 1375 | static inline int audit_del_rule(struct audit_entry *entry, |
fe7752ba DW |
1376 | struct list_head *list) |
1377 | { | |
1378 | struct audit_entry *e; | |
f368c07d AG |
1379 | struct audit_field *inode_f = entry->rule.inode_f; |
1380 | struct audit_watch *watch, *tmp_watch = entry->rule.watch; | |
74c3cbe3 | 1381 | struct audit_tree *tree = entry->rule.tree; |
f368c07d AG |
1382 | LIST_HEAD(inotify_list); |
1383 | int h, ret = 0; | |
471a5c7c AV |
1384 | #ifdef CONFIG_AUDITSYSCALL |
1385 | int dont_count = 0; | |
1386 | ||
1387 | /* If either of these, don't count towards total */ | |
1388 | if (entry->rule.listnr == AUDIT_FILTER_USER || | |
1389 | entry->rule.listnr == AUDIT_FILTER_TYPE) | |
1390 | dont_count = 1; | |
1391 | #endif | |
f368c07d AG |
1392 | |
1393 | if (inode_f) { | |
1394 | h = audit_hash_ino(inode_f->val); | |
1395 | list = &audit_inode_hash[h]; | |
1396 | } | |
fe7752ba | 1397 | |
f368c07d AG |
1398 | mutex_lock(&audit_filter_mutex); |
1399 | e = audit_find_rule(entry, list); | |
1400 | if (!e) { | |
1401 | mutex_unlock(&audit_filter_mutex); | |
1402 | ret = -ENOENT; | |
1403 | goto out; | |
1404 | } | |
1405 | ||
1406 | watch = e->rule.watch; | |
1407 | if (watch) { | |
1408 | struct audit_parent *parent = watch->parent; | |
1409 | ||
1410 | list_del(&e->rule.rlist); | |
1411 | ||
1412 | if (list_empty(&watch->rules)) { | |
1413 | audit_remove_watch(watch); | |
1414 | ||
1415 | if (list_empty(&parent->watches)) { | |
1416 | /* Put parent on the inotify un-registration | |
1417 | * list. Grab a reference before releasing | |
1418 | * audit_filter_mutex, to be released in | |
8f7b0ba1 AV |
1419 | * audit_inotify_unregister(). |
1420 | * If filesystem is going away, just leave | |
1421 | * the sucker alone, eviction will take | |
1422 | * care of it. | |
1423 | */ | |
1424 | if (pin_inotify_watch(&parent->wdata)) | |
1425 | list_add(&parent->ilist, &inotify_list); | |
f368c07d | 1426 | } |
fe7752ba DW |
1427 | } |
1428 | } | |
f368c07d | 1429 | |
74c3cbe3 AV |
1430 | if (e->rule.tree) |
1431 | audit_remove_tree_rule(&e->rule); | |
1432 | ||
f368c07d | 1433 | list_del_rcu(&e->list); |
e45aa212 | 1434 | list_del(&e->rule.list); |
f368c07d AG |
1435 | call_rcu(&e->rcu, audit_free_rule_rcu); |
1436 | ||
471a5c7c AV |
1437 | #ifdef CONFIG_AUDITSYSCALL |
1438 | if (!dont_count) | |
1439 | audit_n_rules--; | |
e54dc243 AG |
1440 | |
1441 | if (!audit_match_signal(entry)) | |
1442 | audit_signals--; | |
471a5c7c | 1443 | #endif |
f368c07d AG |
1444 | mutex_unlock(&audit_filter_mutex); |
1445 | ||
1446 | if (!list_empty(&inotify_list)) | |
1447 | audit_inotify_unregister(&inotify_list); | |
1448 | ||
1449 | out: | |
1450 | if (tmp_watch) | |
1451 | audit_put_watch(tmp_watch); /* match initial get */ | |
74c3cbe3 AV |
1452 | if (tree) |
1453 | audit_put_tree(tree); /* that's the temporary one */ | |
f368c07d AG |
1454 | |
1455 | return ret; | |
fe7752ba DW |
1456 | } |
1457 | ||
93315ed6 AG |
1458 | /* List rules using struct audit_rule. Exists for backward |
1459 | * compatibility with userspace. */ | |
9044e6bc | 1460 | static void audit_list(int pid, int seq, struct sk_buff_head *q) |
fe7752ba | 1461 | { |
9044e6bc | 1462 | struct sk_buff *skb; |
e45aa212 | 1463 | struct audit_krule *r; |
fe7752ba DW |
1464 | int i; |
1465 | ||
f368c07d AG |
1466 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1467 | * iterator to sync with list writers. */ | |
fe7752ba | 1468 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
e45aa212 | 1469 | list_for_each_entry(r, &audit_rules_list[i], list) { |
f368c07d AG |
1470 | struct audit_rule *rule; |
1471 | ||
e45aa212 | 1472 | rule = audit_krule_to_rule(r); |
f368c07d AG |
1473 | if (unlikely(!rule)) |
1474 | break; | |
1475 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, | |
1476 | rule, sizeof(*rule)); | |
1477 | if (skb) | |
1478 | skb_queue_tail(q, skb); | |
1479 | kfree(rule); | |
1480 | } | |
1481 | } | |
9044e6bc AV |
1482 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0); |
1483 | if (skb) | |
1484 | skb_queue_tail(q, skb); | |
fe7752ba DW |
1485 | } |
1486 | ||
93315ed6 | 1487 | /* List rules using struct audit_rule_data. */ |
9044e6bc | 1488 | static void audit_list_rules(int pid, int seq, struct sk_buff_head *q) |
93315ed6 | 1489 | { |
9044e6bc | 1490 | struct sk_buff *skb; |
e45aa212 | 1491 | struct audit_krule *r; |
93315ed6 AG |
1492 | int i; |
1493 | ||
f368c07d AG |
1494 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1495 | * iterator to sync with list writers. */ | |
93315ed6 | 1496 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
e45aa212 | 1497 | list_for_each_entry(r, &audit_rules_list[i], list) { |
f368c07d AG |
1498 | struct audit_rule_data *data; |
1499 | ||
e45aa212 | 1500 | data = audit_krule_to_data(r); |
f368c07d AG |
1501 | if (unlikely(!data)) |
1502 | break; | |
1503 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, | |
1504 | data, sizeof(*data) + data->buflen); | |
9044e6bc AV |
1505 | if (skb) |
1506 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1507 | kfree(data); |
1508 | } | |
1509 | } | |
9044e6bc AV |
1510 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); |
1511 | if (skb) | |
1512 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1513 | } |
1514 | ||
5adc8a6a | 1515 | /* Log rule additions and removals */ |
2532386f EP |
1516 | static void audit_log_rule_change(uid_t loginuid, u32 sessionid, u32 sid, |
1517 | char *action, struct audit_krule *rule, | |
1518 | int res) | |
5adc8a6a AG |
1519 | { |
1520 | struct audit_buffer *ab; | |
1521 | ||
1a6b9f23 EP |
1522 | if (!audit_enabled) |
1523 | return; | |
1524 | ||
5adc8a6a AG |
1525 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
1526 | if (!ab) | |
1527 | return; | |
2532386f | 1528 | audit_log_format(ab, "auid=%u ses=%u", loginuid, sessionid); |
5adc8a6a AG |
1529 | if (sid) { |
1530 | char *ctx = NULL; | |
1531 | u32 len; | |
2a862b32 | 1532 | if (security_secid_to_secctx(sid, &ctx, &len)) |
5adc8a6a | 1533 | audit_log_format(ab, " ssid=%u", sid); |
2a862b32 | 1534 | else { |
5adc8a6a | 1535 | audit_log_format(ab, " subj=%s", ctx); |
2a862b32 AD |
1536 | security_release_secctx(ctx, len); |
1537 | } | |
5adc8a6a | 1538 | } |
a17b4ad7 | 1539 | audit_log_format(ab, " op=%s rule key=", action); |
5adc8a6a AG |
1540 | if (rule->filterkey) |
1541 | audit_log_untrustedstring(ab, rule->filterkey); | |
1542 | else | |
1543 | audit_log_format(ab, "(null)"); | |
1544 | audit_log_format(ab, " list=%d res=%d", rule->listnr, res); | |
1545 | audit_log_end(ab); | |
1546 | } | |
1547 | ||
fe7752ba DW |
1548 | /** |
1549 | * audit_receive_filter - apply all rules to the specified message type | |
1550 | * @type: audit message type | |
1551 | * @pid: target pid for netlink audit messages | |
1552 | * @uid: target uid for netlink audit messages | |
1553 | * @seq: netlink audit message sequence (serial) number | |
1554 | * @data: payload data | |
93315ed6 | 1555 | * @datasz: size of payload data |
fe7752ba | 1556 | * @loginuid: loginuid of sender |
9f0aecdd | 1557 | * @sessionid: sessionid for netlink audit message |
ce29b682 | 1558 | * @sid: SE Linux Security ID of sender |
fe7752ba DW |
1559 | */ |
1560 | int audit_receive_filter(int type, int pid, int uid, int seq, void *data, | |
2532386f | 1561 | size_t datasz, uid_t loginuid, u32 sessionid, u32 sid) |
fe7752ba DW |
1562 | { |
1563 | struct task_struct *tsk; | |
9044e6bc | 1564 | struct audit_netlink_list *dest; |
93315ed6 AG |
1565 | int err = 0; |
1566 | struct audit_entry *entry; | |
fe7752ba DW |
1567 | |
1568 | switch (type) { | |
1569 | case AUDIT_LIST: | |
93315ed6 | 1570 | case AUDIT_LIST_RULES: |
fe7752ba DW |
1571 | /* We can't just spew out the rules here because we might fill |
1572 | * the available socket buffer space and deadlock waiting for | |
1573 | * auditctl to read from it... which isn't ever going to | |
1574 | * happen if we're actually running in the context of auditctl | |
1575 | * trying to _send_ the stuff */ | |
9ce34218 | 1576 | |
9044e6bc | 1577 | dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); |
fe7752ba DW |
1578 | if (!dest) |
1579 | return -ENOMEM; | |
9044e6bc AV |
1580 | dest->pid = pid; |
1581 | skb_queue_head_init(&dest->q); | |
fe7752ba | 1582 | |
f368c07d | 1583 | mutex_lock(&audit_filter_mutex); |
93315ed6 | 1584 | if (type == AUDIT_LIST) |
9044e6bc | 1585 | audit_list(pid, seq, &dest->q); |
93315ed6 | 1586 | else |
9044e6bc | 1587 | audit_list_rules(pid, seq, &dest->q); |
f368c07d | 1588 | mutex_unlock(&audit_filter_mutex); |
9044e6bc AV |
1589 | |
1590 | tsk = kthread_run(audit_send_list, dest, "audit_send_list"); | |
fe7752ba | 1591 | if (IS_ERR(tsk)) { |
9044e6bc | 1592 | skb_queue_purge(&dest->q); |
fe7752ba DW |
1593 | kfree(dest); |
1594 | err = PTR_ERR(tsk); | |
1595 | } | |
1596 | break; | |
1597 | case AUDIT_ADD: | |
93315ed6 AG |
1598 | case AUDIT_ADD_RULE: |
1599 | if (type == AUDIT_ADD) | |
1600 | entry = audit_rule_to_entry(data); | |
1601 | else | |
1602 | entry = audit_data_to_entry(data, datasz); | |
1603 | if (IS_ERR(entry)) | |
1604 | return PTR_ERR(entry); | |
1605 | ||
1606 | err = audit_add_rule(entry, | |
1607 | &audit_filter_list[entry->rule.listnr]); | |
2532386f EP |
1608 | audit_log_rule_change(loginuid, sessionid, sid, "add", |
1609 | &entry->rule, !err); | |
5d330108 SG |
1610 | |
1611 | if (err) | |
93315ed6 | 1612 | audit_free_rule(entry); |
fe7752ba DW |
1613 | break; |
1614 | case AUDIT_DEL: | |
93315ed6 AG |
1615 | case AUDIT_DEL_RULE: |
1616 | if (type == AUDIT_DEL) | |
1617 | entry = audit_rule_to_entry(data); | |
1618 | else | |
1619 | entry = audit_data_to_entry(data, datasz); | |
1620 | if (IS_ERR(entry)) | |
1621 | return PTR_ERR(entry); | |
1622 | ||
1623 | err = audit_del_rule(entry, | |
1624 | &audit_filter_list[entry->rule.listnr]); | |
2532386f EP |
1625 | audit_log_rule_change(loginuid, sessionid, sid, "remove", |
1626 | &entry->rule, !err); | |
5d330108 | 1627 | |
93315ed6 | 1628 | audit_free_rule(entry); |
fe7752ba DW |
1629 | break; |
1630 | default: | |
1631 | return -EINVAL; | |
1632 | } | |
1633 | ||
1634 | return err; | |
1635 | } | |
1636 | ||
1637 | int audit_comparator(const u32 left, const u32 op, const u32 right) | |
1638 | { | |
1639 | switch (op) { | |
1640 | case AUDIT_EQUAL: | |
1641 | return (left == right); | |
1642 | case AUDIT_NOT_EQUAL: | |
1643 | return (left != right); | |
1644 | case AUDIT_LESS_THAN: | |
1645 | return (left < right); | |
1646 | case AUDIT_LESS_THAN_OR_EQUAL: | |
1647 | return (left <= right); | |
1648 | case AUDIT_GREATER_THAN: | |
1649 | return (left > right); | |
1650 | case AUDIT_GREATER_THAN_OR_EQUAL: | |
1651 | return (left >= right); | |
74f2345b EP |
1652 | case AUDIT_BIT_MASK: |
1653 | return (left & right); | |
1654 | case AUDIT_BIT_TEST: | |
1655 | return ((left & right) == right); | |
fe7752ba | 1656 | } |
d9d9ec6e DK |
1657 | BUG(); |
1658 | return 0; | |
fe7752ba DW |
1659 | } |
1660 | ||
f368c07d AG |
1661 | /* Compare given dentry name with last component in given path, |
1662 | * return of 0 indicates a match. */ | |
9c937dcc AG |
1663 | int audit_compare_dname_path(const char *dname, const char *path, |
1664 | int *dirlen) | |
f368c07d AG |
1665 | { |
1666 | int dlen, plen; | |
1667 | const char *p; | |
1668 | ||
1669 | if (!dname || !path) | |
1670 | return 1; | |
1671 | ||
1672 | dlen = strlen(dname); | |
1673 | plen = strlen(path); | |
1674 | if (plen < dlen) | |
1675 | return 1; | |
1676 | ||
1677 | /* disregard trailing slashes */ | |
1678 | p = path + plen - 1; | |
1679 | while ((*p == '/') && (p > path)) | |
1680 | p--; | |
1681 | ||
1682 | /* find last path component */ | |
1683 | p = p - dlen + 1; | |
1684 | if (p < path) | |
1685 | return 1; | |
1686 | else if (p > path) { | |
1687 | if (*--p != '/') | |
1688 | return 1; | |
1689 | else | |
1690 | p++; | |
1691 | } | |
fe7752ba | 1692 | |
9c937dcc AG |
1693 | /* return length of path's directory component */ |
1694 | if (dirlen) | |
1695 | *dirlen = p - path; | |
f368c07d AG |
1696 | return strncmp(p, dname, dlen); |
1697 | } | |
fe7752ba DW |
1698 | |
1699 | static int audit_filter_user_rules(struct netlink_skb_parms *cb, | |
93315ed6 | 1700 | struct audit_krule *rule, |
fe7752ba DW |
1701 | enum audit_state *state) |
1702 | { | |
1703 | int i; | |
1704 | ||
1705 | for (i = 0; i < rule->field_count; i++) { | |
93315ed6 | 1706 | struct audit_field *f = &rule->fields[i]; |
fe7752ba DW |
1707 | int result = 0; |
1708 | ||
93315ed6 | 1709 | switch (f->type) { |
fe7752ba | 1710 | case AUDIT_PID: |
93315ed6 | 1711 | result = audit_comparator(cb->creds.pid, f->op, f->val); |
fe7752ba DW |
1712 | break; |
1713 | case AUDIT_UID: | |
93315ed6 | 1714 | result = audit_comparator(cb->creds.uid, f->op, f->val); |
fe7752ba DW |
1715 | break; |
1716 | case AUDIT_GID: | |
93315ed6 | 1717 | result = audit_comparator(cb->creds.gid, f->op, f->val); |
fe7752ba DW |
1718 | break; |
1719 | case AUDIT_LOGINUID: | |
93315ed6 | 1720 | result = audit_comparator(cb->loginuid, f->op, f->val); |
fe7752ba DW |
1721 | break; |
1722 | } | |
1723 | ||
1724 | if (!result) | |
1725 | return 0; | |
1726 | } | |
1727 | switch (rule->action) { | |
1728 | case AUDIT_NEVER: *state = AUDIT_DISABLED; break; | |
fe7752ba DW |
1729 | case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; |
1730 | } | |
1731 | return 1; | |
1732 | } | |
1733 | ||
d8de7247 | 1734 | int audit_filter_user(struct netlink_skb_parms *cb) |
fe7752ba | 1735 | { |
11f57ced | 1736 | enum audit_state state = AUDIT_DISABLED; |
fe7752ba | 1737 | struct audit_entry *e; |
fe7752ba DW |
1738 | int ret = 1; |
1739 | ||
1740 | rcu_read_lock(); | |
1741 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { | |
1742 | if (audit_filter_user_rules(cb, &e->rule, &state)) { | |
1743 | if (state == AUDIT_DISABLED) | |
1744 | ret = 0; | |
1745 | break; | |
1746 | } | |
1747 | } | |
1748 | rcu_read_unlock(); | |
1749 | ||
1750 | return ret; /* Audit by default */ | |
1751 | } | |
1752 | ||
1753 | int audit_filter_type(int type) | |
1754 | { | |
1755 | struct audit_entry *e; | |
1756 | int result = 0; | |
9ce34218 | 1757 | |
fe7752ba DW |
1758 | rcu_read_lock(); |
1759 | if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE])) | |
1760 | goto unlock_and_return; | |
1761 | ||
1762 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE], | |
1763 | list) { | |
fe7752ba | 1764 | int i; |
93315ed6 AG |
1765 | for (i = 0; i < e->rule.field_count; i++) { |
1766 | struct audit_field *f = &e->rule.fields[i]; | |
1767 | if (f->type == AUDIT_MSGTYPE) { | |
1768 | result = audit_comparator(type, f->op, f->val); | |
fe7752ba DW |
1769 | if (!result) |
1770 | break; | |
1771 | } | |
1772 | } | |
1773 | if (result) | |
1774 | goto unlock_and_return; | |
1775 | } | |
1776 | unlock_and_return: | |
1777 | rcu_read_unlock(); | |
1778 | return result; | |
1779 | } | |
3dc7e315 | 1780 | |
e45aa212 | 1781 | static int update_lsm_rule(struct audit_krule *r) |
1a9d0797 | 1782 | { |
e45aa212 | 1783 | struct audit_entry *entry = container_of(r, struct audit_entry, rule); |
1a9d0797 AV |
1784 | struct audit_entry *nentry; |
1785 | struct audit_watch *watch; | |
1786 | struct audit_tree *tree; | |
1787 | int err = 0; | |
1788 | ||
e45aa212 | 1789 | if (!security_audit_rule_known(r)) |
1a9d0797 AV |
1790 | return 0; |
1791 | ||
e45aa212 AV |
1792 | watch = r->watch; |
1793 | tree = r->tree; | |
1794 | nentry = audit_dupe_rule(r, watch); | |
1a9d0797 AV |
1795 | if (IS_ERR(nentry)) { |
1796 | /* save the first error encountered for the | |
1797 | * return value */ | |
1798 | err = PTR_ERR(nentry); | |
1799 | audit_panic("error updating LSM filters"); | |
1800 | if (watch) | |
e45aa212 | 1801 | list_del(&r->rlist); |
1a9d0797 | 1802 | list_del_rcu(&entry->list); |
e45aa212 | 1803 | list_del(&r->list); |
1a9d0797 AV |
1804 | } else { |
1805 | if (watch) { | |
1806 | list_add(&nentry->rule.rlist, &watch->rules); | |
e45aa212 | 1807 | list_del(&r->rlist); |
1a9d0797 | 1808 | } else if (tree) |
e45aa212 | 1809 | list_replace_init(&r->rlist, &nentry->rule.rlist); |
1a9d0797 | 1810 | list_replace_rcu(&entry->list, &nentry->list); |
e45aa212 | 1811 | list_replace(&r->list, &nentry->rule.list); |
1a9d0797 AV |
1812 | } |
1813 | call_rcu(&entry->rcu, audit_free_rule_rcu); | |
1814 | ||
1815 | return err; | |
1816 | } | |
1817 | ||
04305e4a | 1818 | /* This function will re-initialize the lsm_rule field of all applicable rules. |
d7a96f3a | 1819 | * It will traverse the filter lists serarching for rules that contain LSM |
3dc7e315 | 1820 | * specific filter fields. When such a rule is found, it is copied, the |
d7a96f3a | 1821 | * LSM field is re-initialized, and the old rule is replaced with the |
3dc7e315 | 1822 | * updated rule. */ |
d7a96f3a | 1823 | int audit_update_lsm_rules(void) |
3dc7e315 | 1824 | { |
e45aa212 | 1825 | struct audit_krule *r, *n; |
3dc7e315 DG |
1826 | int i, err = 0; |
1827 | ||
f368c07d AG |
1828 | /* audit_filter_mutex synchronizes the writers */ |
1829 | mutex_lock(&audit_filter_mutex); | |
3dc7e315 DG |
1830 | |
1831 | for (i = 0; i < AUDIT_NR_FILTERS; i++) { | |
e45aa212 AV |
1832 | list_for_each_entry_safe(r, n, &audit_rules_list[i], list) { |
1833 | int res = update_lsm_rule(r); | |
1a9d0797 AV |
1834 | if (!err) |
1835 | err = res; | |
3dc7e315 DG |
1836 | } |
1837 | } | |
f368c07d | 1838 | mutex_unlock(&audit_filter_mutex); |
3dc7e315 DG |
1839 | |
1840 | return err; | |
1841 | } | |
f368c07d AG |
1842 | |
1843 | /* Update watch data in audit rules based on inotify events. */ | |
1844 | void audit_handle_ievent(struct inotify_watch *i_watch, u32 wd, u32 mask, | |
1845 | u32 cookie, const char *dname, struct inode *inode) | |
1846 | { | |
1847 | struct audit_parent *parent; | |
1848 | ||
1849 | parent = container_of(i_watch, struct audit_parent, wdata); | |
1850 | ||
1851 | if (mask & (IN_CREATE|IN_MOVED_TO) && inode) | |
1852 | audit_update_watch(parent, dname, inode->i_sb->s_dev, | |
1853 | inode->i_ino, 0); | |
1854 | else if (mask & (IN_DELETE|IN_MOVED_FROM)) | |
1855 | audit_update_watch(parent, dname, (dev_t)-1, (unsigned long)-1, 1); | |
1856 | /* inotify automatically removes the watch and sends IN_IGNORED */ | |
1857 | else if (mask & (IN_DELETE_SELF|IN_UNMOUNT)) | |
1858 | audit_remove_parent_watches(parent); | |
1859 | /* inotify does not remove the watch, so remove it manually */ | |
1860 | else if(mask & IN_MOVE_SELF) { | |
1861 | audit_remove_parent_watches(parent); | |
1862 | inotify_remove_watch_locked(audit_ih, i_watch); | |
1863 | } else if (mask & IN_IGNORED) | |
1864 | put_inotify_watch(i_watch); | |
1865 | } |