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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> |
3dc7e315 | 32 | #include <linux/selinux.h> |
fe7752ba DW |
33 | #include "audit.h" |
34 | ||
f368c07d AG |
35 | /* |
36 | * Locking model: | |
37 | * | |
38 | * audit_filter_mutex: | |
39 | * Synchronizes writes and blocking reads of audit's filterlist | |
40 | * data. Rcu is used to traverse the filterlist and access | |
41 | * contents of structs audit_entry, audit_watch and opaque | |
42 | * selinux rules during filtering. If modified, these structures | |
43 | * must be copied and replace their counterparts in the filterlist. | |
44 | * An audit_parent struct is not accessed during filtering, so may | |
45 | * be written directly provided audit_filter_mutex is held. | |
46 | */ | |
47 | ||
48 | /* | |
49 | * Reference counting: | |
50 | * | |
51 | * audit_parent: lifetime is from audit_init_parent() to receipt of an IN_IGNORED | |
52 | * event. Each audit_watch holds a reference to its associated parent. | |
53 | * | |
54 | * audit_watch: if added to lists, lifetime is from audit_init_watch() to | |
55 | * audit_remove_watch(). Additionally, an audit_watch may exist | |
56 | * temporarily to assist in searching existing filter data. Each | |
57 | * audit_krule holds a reference to its associated watch. | |
58 | */ | |
59 | ||
60 | struct audit_parent { | |
61 | struct list_head ilist; /* entry in inotify registration list */ | |
62 | struct list_head watches; /* associated watches */ | |
63 | struct inotify_watch wdata; /* inotify watch data */ | |
64 | unsigned flags; /* status flags */ | |
65 | }; | |
66 | ||
67 | /* | |
68 | * audit_parent status flags: | |
69 | * | |
70 | * AUDIT_PARENT_INVALID - set anytime rules/watches are auto-removed due to | |
71 | * a filesystem event to ensure we're adding audit watches to a valid parent. | |
72 | * Technically not needed for IN_DELETE_SELF or IN_UNMOUNT events, as we cannot | |
73 | * receive them while we have nameidata, but must be used for IN_MOVE_SELF which | |
74 | * we can receive while holding nameidata. | |
75 | */ | |
76 | #define AUDIT_PARENT_INVALID 0x001 | |
77 | ||
78 | /* Audit filter lists, defined in <linux/audit.h> */ | |
fe7752ba DW |
79 | struct list_head audit_filter_list[AUDIT_NR_FILTERS] = { |
80 | LIST_HEAD_INIT(audit_filter_list[0]), | |
81 | LIST_HEAD_INIT(audit_filter_list[1]), | |
82 | LIST_HEAD_INIT(audit_filter_list[2]), | |
83 | LIST_HEAD_INIT(audit_filter_list[3]), | |
84 | LIST_HEAD_INIT(audit_filter_list[4]), | |
85 | LIST_HEAD_INIT(audit_filter_list[5]), | |
86 | #if AUDIT_NR_FILTERS != 6 | |
87 | #error Fix audit_filter_list initialiser | |
88 | #endif | |
89 | }; | |
90 | ||
74c3cbe3 | 91 | DEFINE_MUTEX(audit_filter_mutex); |
f368c07d AG |
92 | |
93 | /* Inotify handle */ | |
94 | extern struct inotify_handle *audit_ih; | |
95 | ||
96 | /* Inotify events we care about. */ | |
97 | #define AUDIT_IN_WATCH IN_MOVE|IN_CREATE|IN_DELETE|IN_DELETE_SELF|IN_MOVE_SELF | |
98 | ||
1a6b9f23 EP |
99 | extern int audit_enabled; |
100 | ||
f368c07d AG |
101 | void audit_free_parent(struct inotify_watch *i_watch) |
102 | { | |
103 | struct audit_parent *parent; | |
104 | ||
105 | parent = container_of(i_watch, struct audit_parent, wdata); | |
106 | WARN_ON(!list_empty(&parent->watches)); | |
107 | kfree(parent); | |
108 | } | |
109 | ||
110 | static inline void audit_get_watch(struct audit_watch *watch) | |
111 | { | |
112 | atomic_inc(&watch->count); | |
113 | } | |
114 | ||
115 | static void audit_put_watch(struct audit_watch *watch) | |
116 | { | |
117 | if (atomic_dec_and_test(&watch->count)) { | |
118 | WARN_ON(watch->parent); | |
119 | WARN_ON(!list_empty(&watch->rules)); | |
120 | kfree(watch->path); | |
121 | kfree(watch); | |
122 | } | |
123 | } | |
124 | ||
125 | static void audit_remove_watch(struct audit_watch *watch) | |
126 | { | |
127 | list_del(&watch->wlist); | |
128 | put_inotify_watch(&watch->parent->wdata); | |
129 | watch->parent = NULL; | |
130 | audit_put_watch(watch); /* match initial get */ | |
131 | } | |
132 | ||
93315ed6 | 133 | static inline void audit_free_rule(struct audit_entry *e) |
fe7752ba | 134 | { |
3dc7e315 | 135 | int i; |
f368c07d AG |
136 | |
137 | /* some rules don't have associated watches */ | |
138 | if (e->rule.watch) | |
139 | audit_put_watch(e->rule.watch); | |
3dc7e315 DG |
140 | if (e->rule.fields) |
141 | for (i = 0; i < e->rule.field_count; i++) { | |
142 | struct audit_field *f = &e->rule.fields[i]; | |
143 | kfree(f->se_str); | |
144 | selinux_audit_rule_free(f->se_rule); | |
145 | } | |
93315ed6 | 146 | kfree(e->rule.fields); |
5adc8a6a | 147 | kfree(e->rule.filterkey); |
93315ed6 AG |
148 | kfree(e); |
149 | } | |
150 | ||
74c3cbe3 | 151 | void audit_free_rule_rcu(struct rcu_head *head) |
93315ed6 AG |
152 | { |
153 | struct audit_entry *e = container_of(head, struct audit_entry, rcu); | |
154 | audit_free_rule(e); | |
155 | } | |
156 | ||
f368c07d AG |
157 | /* Initialize a parent watch entry. */ |
158 | static struct audit_parent *audit_init_parent(struct nameidata *ndp) | |
159 | { | |
160 | struct audit_parent *parent; | |
161 | s32 wd; | |
162 | ||
163 | parent = kzalloc(sizeof(*parent), GFP_KERNEL); | |
164 | if (unlikely(!parent)) | |
165 | return ERR_PTR(-ENOMEM); | |
166 | ||
167 | INIT_LIST_HEAD(&parent->watches); | |
168 | parent->flags = 0; | |
169 | ||
170 | inotify_init_watch(&parent->wdata); | |
171 | /* grab a ref so inotify watch hangs around until we take audit_filter_mutex */ | |
172 | get_inotify_watch(&parent->wdata); | |
4ac91378 JB |
173 | wd = inotify_add_watch(audit_ih, &parent->wdata, |
174 | ndp->path.dentry->d_inode, AUDIT_IN_WATCH); | |
f368c07d AG |
175 | if (wd < 0) { |
176 | audit_free_parent(&parent->wdata); | |
177 | return ERR_PTR(wd); | |
178 | } | |
179 | ||
180 | return parent; | |
181 | } | |
182 | ||
183 | /* Initialize a watch entry. */ | |
184 | static struct audit_watch *audit_init_watch(char *path) | |
185 | { | |
186 | struct audit_watch *watch; | |
187 | ||
188 | watch = kzalloc(sizeof(*watch), GFP_KERNEL); | |
189 | if (unlikely(!watch)) | |
190 | return ERR_PTR(-ENOMEM); | |
191 | ||
192 | INIT_LIST_HEAD(&watch->rules); | |
193 | atomic_set(&watch->count, 1); | |
194 | watch->path = path; | |
195 | watch->dev = (dev_t)-1; | |
196 | watch->ino = (unsigned long)-1; | |
197 | ||
198 | return watch; | |
199 | } | |
200 | ||
3dc7e315 DG |
201 | /* Initialize an audit filterlist entry. */ |
202 | static inline struct audit_entry *audit_init_entry(u32 field_count) | |
203 | { | |
204 | struct audit_entry *entry; | |
205 | struct audit_field *fields; | |
206 | ||
207 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
208 | if (unlikely(!entry)) | |
209 | return NULL; | |
210 | ||
211 | fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL); | |
212 | if (unlikely(!fields)) { | |
213 | kfree(entry); | |
214 | return NULL; | |
215 | } | |
216 | entry->rule.fields = fields; | |
217 | ||
218 | return entry; | |
219 | } | |
220 | ||
93315ed6 AG |
221 | /* Unpack a filter field's string representation from user-space |
222 | * buffer. */ | |
74c3cbe3 | 223 | char *audit_unpack_string(void **bufp, size_t *remain, size_t len) |
93315ed6 AG |
224 | { |
225 | char *str; | |
226 | ||
227 | if (!*bufp || (len == 0) || (len > *remain)) | |
228 | return ERR_PTR(-EINVAL); | |
229 | ||
230 | /* Of the currently implemented string fields, PATH_MAX | |
231 | * defines the longest valid length. | |
232 | */ | |
233 | if (len > PATH_MAX) | |
234 | return ERR_PTR(-ENAMETOOLONG); | |
235 | ||
236 | str = kmalloc(len + 1, GFP_KERNEL); | |
237 | if (unlikely(!str)) | |
238 | return ERR_PTR(-ENOMEM); | |
239 | ||
240 | memcpy(str, *bufp, len); | |
241 | str[len] = 0; | |
242 | *bufp += len; | |
243 | *remain -= len; | |
244 | ||
245 | return str; | |
246 | } | |
247 | ||
f368c07d AG |
248 | /* Translate an inode field to kernel respresentation. */ |
249 | static inline int audit_to_inode(struct audit_krule *krule, | |
250 | struct audit_field *f) | |
251 | { | |
252 | if (krule->listnr != AUDIT_FILTER_EXIT || | |
74c3cbe3 | 253 | krule->watch || krule->inode_f || krule->tree) |
f368c07d AG |
254 | return -EINVAL; |
255 | ||
256 | krule->inode_f = f; | |
257 | return 0; | |
258 | } | |
259 | ||
260 | /* Translate a watch string to kernel respresentation. */ | |
261 | static int audit_to_watch(struct audit_krule *krule, char *path, int len, | |
262 | u32 op) | |
263 | { | |
264 | struct audit_watch *watch; | |
265 | ||
266 | if (!audit_ih) | |
267 | return -EOPNOTSUPP; | |
268 | ||
269 | if (path[0] != '/' || path[len-1] == '/' || | |
270 | krule->listnr != AUDIT_FILTER_EXIT || | |
271 | op & ~AUDIT_EQUAL || | |
74c3cbe3 | 272 | krule->inode_f || krule->watch || krule->tree) |
f368c07d AG |
273 | return -EINVAL; |
274 | ||
275 | watch = audit_init_watch(path); | |
276 | if (unlikely(IS_ERR(watch))) | |
277 | return PTR_ERR(watch); | |
278 | ||
279 | audit_get_watch(watch); | |
280 | krule->watch = watch; | |
281 | ||
282 | return 0; | |
283 | } | |
284 | ||
b915543b AV |
285 | static __u32 *classes[AUDIT_SYSCALL_CLASSES]; |
286 | ||
287 | int __init audit_register_class(int class, unsigned *list) | |
288 | { | |
289 | __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL); | |
290 | if (!p) | |
291 | return -ENOMEM; | |
292 | while (*list != ~0U) { | |
293 | unsigned n = *list++; | |
294 | if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { | |
295 | kfree(p); | |
296 | return -EINVAL; | |
297 | } | |
298 | p[AUDIT_WORD(n)] |= AUDIT_BIT(n); | |
299 | } | |
300 | if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { | |
301 | kfree(p); | |
302 | return -EINVAL; | |
303 | } | |
304 | classes[class] = p; | |
305 | return 0; | |
306 | } | |
307 | ||
55669bfa AV |
308 | int audit_match_class(int class, unsigned syscall) |
309 | { | |
c926e4f4 | 310 | if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32)) |
55669bfa AV |
311 | return 0; |
312 | if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) | |
313 | return 0; | |
314 | return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); | |
315 | } | |
316 | ||
327b9eeb | 317 | #ifdef CONFIG_AUDITSYSCALL |
e54dc243 AG |
318 | static inline int audit_match_class_bits(int class, u32 *mask) |
319 | { | |
320 | int i; | |
321 | ||
322 | if (classes[class]) { | |
323 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
324 | if (mask[i] & classes[class][i]) | |
325 | return 0; | |
326 | } | |
327 | return 1; | |
328 | } | |
329 | ||
330 | static int audit_match_signal(struct audit_entry *entry) | |
331 | { | |
332 | struct audit_field *arch = entry->rule.arch_f; | |
333 | ||
334 | if (!arch) { | |
335 | /* When arch is unspecified, we must check both masks on biarch | |
336 | * as syscall number alone is ambiguous. */ | |
337 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
338 | entry->rule.mask) && | |
339 | audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
340 | entry->rule.mask)); | |
341 | } | |
342 | ||
343 | switch(audit_classify_arch(arch->val)) { | |
344 | case 0: /* native */ | |
345 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
346 | entry->rule.mask)); | |
347 | case 1: /* 32bit on biarch */ | |
348 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
349 | entry->rule.mask)); | |
350 | default: | |
351 | return 1; | |
352 | } | |
353 | } | |
327b9eeb | 354 | #endif |
e54dc243 | 355 | |
93315ed6 AG |
356 | /* Common user-space to kernel rule translation. */ |
357 | static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) | |
358 | { | |
359 | unsigned listnr; | |
360 | struct audit_entry *entry; | |
93315ed6 AG |
361 | int i, err; |
362 | ||
363 | err = -EINVAL; | |
364 | listnr = rule->flags & ~AUDIT_FILTER_PREPEND; | |
365 | switch(listnr) { | |
366 | default: | |
367 | goto exit_err; | |
368 | case AUDIT_FILTER_USER: | |
369 | case AUDIT_FILTER_TYPE: | |
370 | #ifdef CONFIG_AUDITSYSCALL | |
371 | case AUDIT_FILTER_ENTRY: | |
372 | case AUDIT_FILTER_EXIT: | |
373 | case AUDIT_FILTER_TASK: | |
374 | #endif | |
375 | ; | |
376 | } | |
014149cc AV |
377 | if (unlikely(rule->action == AUDIT_POSSIBLE)) { |
378 | printk(KERN_ERR "AUDIT_POSSIBLE is deprecated\n"); | |
379 | goto exit_err; | |
380 | } | |
381 | if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS) | |
93315ed6 AG |
382 | goto exit_err; |
383 | if (rule->field_count > AUDIT_MAX_FIELDS) | |
384 | goto exit_err; | |
385 | ||
386 | err = -ENOMEM; | |
3dc7e315 DG |
387 | entry = audit_init_entry(rule->field_count); |
388 | if (!entry) | |
93315ed6 | 389 | goto exit_err; |
93315ed6 AG |
390 | |
391 | entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND; | |
392 | entry->rule.listnr = listnr; | |
393 | entry->rule.action = rule->action; | |
394 | entry->rule.field_count = rule->field_count; | |
93315ed6 AG |
395 | |
396 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
397 | entry->rule.mask[i] = rule->mask[i]; | |
398 | ||
b915543b AV |
399 | for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { |
400 | int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; | |
401 | __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; | |
402 | __u32 *class; | |
403 | ||
404 | if (!(*p & AUDIT_BIT(bit))) | |
405 | continue; | |
406 | *p &= ~AUDIT_BIT(bit); | |
407 | class = classes[i]; | |
408 | if (class) { | |
409 | int j; | |
410 | for (j = 0; j < AUDIT_BITMASK_SIZE; j++) | |
411 | entry->rule.mask[j] |= class[j]; | |
412 | } | |
413 | } | |
414 | ||
93315ed6 AG |
415 | return entry; |
416 | ||
417 | exit_err: | |
418 | return ERR_PTR(err); | |
419 | } | |
420 | ||
421 | /* Translate struct audit_rule to kernel's rule respresentation. | |
422 | * Exists for backward compatibility with userspace. */ | |
423 | static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) | |
424 | { | |
425 | struct audit_entry *entry; | |
f368c07d | 426 | struct audit_field *f; |
93315ed6 | 427 | int err = 0; |
fe7752ba DW |
428 | int i; |
429 | ||
93315ed6 AG |
430 | entry = audit_to_entry_common(rule); |
431 | if (IS_ERR(entry)) | |
432 | goto exit_nofree; | |
433 | ||
434 | for (i = 0; i < rule->field_count; i++) { | |
435 | struct audit_field *f = &entry->rule.fields[i]; | |
436 | ||
93315ed6 AG |
437 | f->op = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS); |
438 | f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS); | |
439 | f->val = rule->values[i]; | |
440 | ||
f368c07d | 441 | err = -EINVAL; |
f368c07d | 442 | switch(f->type) { |
0a73dccc | 443 | default: |
3dc7e315 | 444 | goto exit_free; |
0a73dccc AV |
445 | case AUDIT_PID: |
446 | case AUDIT_UID: | |
447 | case AUDIT_EUID: | |
448 | case AUDIT_SUID: | |
449 | case AUDIT_FSUID: | |
450 | case AUDIT_GID: | |
451 | case AUDIT_EGID: | |
452 | case AUDIT_SGID: | |
453 | case AUDIT_FSGID: | |
454 | case AUDIT_LOGINUID: | |
455 | case AUDIT_PERS: | |
0a73dccc | 456 | case AUDIT_MSGTYPE: |
3b33ac31 | 457 | case AUDIT_PPID: |
0a73dccc AV |
458 | case AUDIT_DEVMAJOR: |
459 | case AUDIT_DEVMINOR: | |
460 | case AUDIT_EXIT: | |
461 | case AUDIT_SUCCESS: | |
74f2345b EP |
462 | /* bit ops are only useful on syscall args */ |
463 | if (f->op == AUDIT_BIT_MASK || | |
464 | f->op == AUDIT_BIT_TEST) { | |
465 | err = -EINVAL; | |
466 | goto exit_free; | |
467 | } | |
468 | break; | |
0a73dccc AV |
469 | case AUDIT_ARG0: |
470 | case AUDIT_ARG1: | |
471 | case AUDIT_ARG2: | |
472 | case AUDIT_ARG3: | |
473 | break; | |
4b8a311b EP |
474 | /* arch is only allowed to be = or != */ |
475 | case AUDIT_ARCH: | |
476 | if ((f->op != AUDIT_NOT_EQUAL) && (f->op != AUDIT_EQUAL) | |
477 | && (f->op != AUDIT_NEGATE) && (f->op)) { | |
478 | err = -EINVAL; | |
479 | goto exit_free; | |
480 | } | |
e54dc243 | 481 | entry->rule.arch_f = f; |
4b8a311b | 482 | break; |
55669bfa AV |
483 | case AUDIT_PERM: |
484 | if (f->val & ~15) | |
485 | goto exit_free; | |
486 | break; | |
f368c07d AG |
487 | case AUDIT_INODE: |
488 | err = audit_to_inode(&entry->rule, f); | |
489 | if (err) | |
490 | goto exit_free; | |
491 | break; | |
3dc7e315 DG |
492 | } |
493 | ||
93315ed6 | 494 | entry->rule.vers_ops = (f->op & AUDIT_OPERATORS) ? 2 : 1; |
d9d9ec6e DK |
495 | |
496 | /* Support for legacy operators where | |
497 | * AUDIT_NEGATE bit signifies != and otherwise assumes == */ | |
93315ed6 | 498 | if (f->op & AUDIT_NEGATE) |
d9d9ec6e DK |
499 | f->op = AUDIT_NOT_EQUAL; |
500 | else if (!f->op) | |
501 | f->op = AUDIT_EQUAL; | |
502 | else if (f->op == AUDIT_OPERATORS) { | |
503 | err = -EINVAL; | |
504 | goto exit_free; | |
505 | } | |
fe7752ba | 506 | } |
93315ed6 | 507 | |
f368c07d AG |
508 | f = entry->rule.inode_f; |
509 | if (f) { | |
510 | switch(f->op) { | |
511 | case AUDIT_NOT_EQUAL: | |
512 | entry->rule.inode_f = NULL; | |
513 | case AUDIT_EQUAL: | |
514 | break; | |
515 | default: | |
5422e01a | 516 | err = -EINVAL; |
f368c07d AG |
517 | goto exit_free; |
518 | } | |
519 | } | |
520 | ||
93315ed6 AG |
521 | exit_nofree: |
522 | return entry; | |
523 | ||
524 | exit_free: | |
525 | audit_free_rule(entry); | |
526 | return ERR_PTR(err); | |
fe7752ba DW |
527 | } |
528 | ||
93315ed6 AG |
529 | /* Translate struct audit_rule_data to kernel's rule respresentation. */ |
530 | static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, | |
531 | size_t datasz) | |
fe7752ba | 532 | { |
93315ed6 AG |
533 | int err = 0; |
534 | struct audit_entry *entry; | |
f368c07d | 535 | struct audit_field *f; |
93315ed6 | 536 | void *bufp; |
3dc7e315 | 537 | size_t remain = datasz - sizeof(struct audit_rule_data); |
fe7752ba | 538 | int i; |
3dc7e315 | 539 | char *str; |
fe7752ba | 540 | |
93315ed6 AG |
541 | entry = audit_to_entry_common((struct audit_rule *)data); |
542 | if (IS_ERR(entry)) | |
543 | goto exit_nofree; | |
fe7752ba | 544 | |
93315ed6 AG |
545 | bufp = data->buf; |
546 | entry->rule.vers_ops = 2; | |
547 | for (i = 0; i < data->field_count; i++) { | |
548 | struct audit_field *f = &entry->rule.fields[i]; | |
549 | ||
550 | err = -EINVAL; | |
551 | if (!(data->fieldflags[i] & AUDIT_OPERATORS) || | |
552 | data->fieldflags[i] & ~AUDIT_OPERATORS) | |
553 | goto exit_free; | |
554 | ||
555 | f->op = data->fieldflags[i] & AUDIT_OPERATORS; | |
556 | f->type = data->fields[i]; | |
3dc7e315 DG |
557 | f->val = data->values[i]; |
558 | f->se_str = NULL; | |
559 | f->se_rule = NULL; | |
93315ed6 | 560 | switch(f->type) { |
0a73dccc AV |
561 | case AUDIT_PID: |
562 | case AUDIT_UID: | |
563 | case AUDIT_EUID: | |
564 | case AUDIT_SUID: | |
565 | case AUDIT_FSUID: | |
566 | case AUDIT_GID: | |
567 | case AUDIT_EGID: | |
568 | case AUDIT_SGID: | |
569 | case AUDIT_FSGID: | |
570 | case AUDIT_LOGINUID: | |
571 | case AUDIT_PERS: | |
0a73dccc AV |
572 | case AUDIT_MSGTYPE: |
573 | case AUDIT_PPID: | |
574 | case AUDIT_DEVMAJOR: | |
575 | case AUDIT_DEVMINOR: | |
576 | case AUDIT_EXIT: | |
577 | case AUDIT_SUCCESS: | |
578 | case AUDIT_ARG0: | |
579 | case AUDIT_ARG1: | |
580 | case AUDIT_ARG2: | |
581 | case AUDIT_ARG3: | |
582 | break; | |
e54dc243 AG |
583 | case AUDIT_ARCH: |
584 | entry->rule.arch_f = f; | |
585 | break; | |
3a6b9f85 DG |
586 | case AUDIT_SUBJ_USER: |
587 | case AUDIT_SUBJ_ROLE: | |
588 | case AUDIT_SUBJ_TYPE: | |
589 | case AUDIT_SUBJ_SEN: | |
590 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
591 | case AUDIT_OBJ_USER: |
592 | case AUDIT_OBJ_ROLE: | |
593 | case AUDIT_OBJ_TYPE: | |
594 | case AUDIT_OBJ_LEV_LOW: | |
595 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
596 | str = audit_unpack_string(&bufp, &remain, f->val); |
597 | if (IS_ERR(str)) | |
598 | goto exit_free; | |
599 | entry->rule.buflen += f->val; | |
600 | ||
601 | err = selinux_audit_rule_init(f->type, f->op, str, | |
602 | &f->se_rule); | |
603 | /* Keep currently invalid fields around in case they | |
604 | * become valid after a policy reload. */ | |
605 | if (err == -EINVAL) { | |
606 | printk(KERN_WARNING "audit rule for selinux " | |
607 | "\'%s\' is invalid\n", str); | |
608 | err = 0; | |
609 | } | |
610 | if (err) { | |
611 | kfree(str); | |
612 | goto exit_free; | |
613 | } else | |
614 | f->se_str = str; | |
615 | break; | |
f368c07d AG |
616 | case AUDIT_WATCH: |
617 | str = audit_unpack_string(&bufp, &remain, f->val); | |
618 | if (IS_ERR(str)) | |
619 | goto exit_free; | |
620 | entry->rule.buflen += f->val; | |
621 | ||
622 | err = audit_to_watch(&entry->rule, str, f->val, f->op); | |
623 | if (err) { | |
624 | kfree(str); | |
625 | goto exit_free; | |
626 | } | |
627 | break; | |
74c3cbe3 AV |
628 | case AUDIT_DIR: |
629 | str = audit_unpack_string(&bufp, &remain, f->val); | |
630 | if (IS_ERR(str)) | |
631 | goto exit_free; | |
632 | entry->rule.buflen += f->val; | |
633 | ||
634 | err = audit_make_tree(&entry->rule, str, f->op); | |
635 | kfree(str); | |
636 | if (err) | |
637 | goto exit_free; | |
638 | break; | |
f368c07d AG |
639 | case AUDIT_INODE: |
640 | err = audit_to_inode(&entry->rule, f); | |
641 | if (err) | |
642 | goto exit_free; | |
643 | break; | |
5adc8a6a AG |
644 | case AUDIT_FILTERKEY: |
645 | err = -EINVAL; | |
646 | if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN) | |
647 | goto exit_free; | |
648 | str = audit_unpack_string(&bufp, &remain, f->val); | |
649 | if (IS_ERR(str)) | |
650 | goto exit_free; | |
651 | entry->rule.buflen += f->val; | |
652 | entry->rule.filterkey = str; | |
653 | break; | |
55669bfa AV |
654 | case AUDIT_PERM: |
655 | if (f->val & ~15) | |
656 | goto exit_free; | |
657 | break; | |
0a73dccc AV |
658 | default: |
659 | goto exit_free; | |
f368c07d AG |
660 | } |
661 | } | |
662 | ||
663 | f = entry->rule.inode_f; | |
664 | if (f) { | |
665 | switch(f->op) { | |
666 | case AUDIT_NOT_EQUAL: | |
667 | entry->rule.inode_f = NULL; | |
668 | case AUDIT_EQUAL: | |
669 | break; | |
670 | default: | |
5422e01a | 671 | err = -EINVAL; |
f368c07d | 672 | goto exit_free; |
93315ed6 AG |
673 | } |
674 | } | |
675 | ||
676 | exit_nofree: | |
677 | return entry; | |
678 | ||
679 | exit_free: | |
680 | audit_free_rule(entry); | |
681 | return ERR_PTR(err); | |
682 | } | |
683 | ||
684 | /* Pack a filter field's string representation into data block. */ | |
74c3cbe3 | 685 | static inline size_t audit_pack_string(void **bufp, const char *str) |
93315ed6 AG |
686 | { |
687 | size_t len = strlen(str); | |
688 | ||
689 | memcpy(*bufp, str, len); | |
690 | *bufp += len; | |
691 | ||
692 | return len; | |
693 | } | |
694 | ||
695 | /* Translate kernel rule respresentation to struct audit_rule. | |
696 | * Exists for backward compatibility with userspace. */ | |
697 | static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule) | |
698 | { | |
699 | struct audit_rule *rule; | |
700 | int i; | |
701 | ||
4668edc3 | 702 | rule = kzalloc(sizeof(*rule), GFP_KERNEL); |
93315ed6 | 703 | if (unlikely(!rule)) |
0a3b483e | 704 | return NULL; |
93315ed6 AG |
705 | |
706 | rule->flags = krule->flags | krule->listnr; | |
707 | rule->action = krule->action; | |
708 | rule->field_count = krule->field_count; | |
709 | for (i = 0; i < rule->field_count; i++) { | |
710 | rule->values[i] = krule->fields[i].val; | |
711 | rule->fields[i] = krule->fields[i].type; | |
712 | ||
713 | if (krule->vers_ops == 1) { | |
714 | if (krule->fields[i].op & AUDIT_NOT_EQUAL) | |
715 | rule->fields[i] |= AUDIT_NEGATE; | |
716 | } else { | |
717 | rule->fields[i] |= krule->fields[i].op; | |
718 | } | |
719 | } | |
720 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i]; | |
721 | ||
722 | return rule; | |
723 | } | |
fe7752ba | 724 | |
93315ed6 AG |
725 | /* Translate kernel rule respresentation to struct audit_rule_data. */ |
726 | static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) | |
727 | { | |
728 | struct audit_rule_data *data; | |
729 | void *bufp; | |
730 | int i; | |
731 | ||
732 | data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); | |
733 | if (unlikely(!data)) | |
0a3b483e | 734 | return NULL; |
93315ed6 AG |
735 | memset(data, 0, sizeof(*data)); |
736 | ||
737 | data->flags = krule->flags | krule->listnr; | |
738 | data->action = krule->action; | |
739 | data->field_count = krule->field_count; | |
740 | bufp = data->buf; | |
741 | for (i = 0; i < data->field_count; i++) { | |
742 | struct audit_field *f = &krule->fields[i]; | |
743 | ||
744 | data->fields[i] = f->type; | |
745 | data->fieldflags[i] = f->op; | |
746 | switch(f->type) { | |
3a6b9f85 DG |
747 | case AUDIT_SUBJ_USER: |
748 | case AUDIT_SUBJ_ROLE: | |
749 | case AUDIT_SUBJ_TYPE: | |
750 | case AUDIT_SUBJ_SEN: | |
751 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
752 | case AUDIT_OBJ_USER: |
753 | case AUDIT_OBJ_ROLE: | |
754 | case AUDIT_OBJ_TYPE: | |
755 | case AUDIT_OBJ_LEV_LOW: | |
756 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
757 | data->buflen += data->values[i] = |
758 | audit_pack_string(&bufp, f->se_str); | |
759 | break; | |
f368c07d AG |
760 | case AUDIT_WATCH: |
761 | data->buflen += data->values[i] = | |
762 | audit_pack_string(&bufp, krule->watch->path); | |
763 | break; | |
74c3cbe3 AV |
764 | case AUDIT_DIR: |
765 | data->buflen += data->values[i] = | |
766 | audit_pack_string(&bufp, | |
767 | audit_tree_path(krule->tree)); | |
768 | break; | |
5adc8a6a AG |
769 | case AUDIT_FILTERKEY: |
770 | data->buflen += data->values[i] = | |
771 | audit_pack_string(&bufp, krule->filterkey); | |
772 | break; | |
93315ed6 AG |
773 | default: |
774 | data->values[i] = f->val; | |
775 | } | |
776 | } | |
777 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i]; | |
778 | ||
779 | return data; | |
780 | } | |
781 | ||
782 | /* Compare two rules in kernel format. Considered success if rules | |
783 | * don't match. */ | |
784 | static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) | |
785 | { | |
786 | int i; | |
787 | ||
788 | if (a->flags != b->flags || | |
789 | a->listnr != b->listnr || | |
790 | a->action != b->action || | |
791 | a->field_count != b->field_count) | |
fe7752ba DW |
792 | return 1; |
793 | ||
794 | for (i = 0; i < a->field_count; i++) { | |
93315ed6 AG |
795 | if (a->fields[i].type != b->fields[i].type || |
796 | a->fields[i].op != b->fields[i].op) | |
fe7752ba | 797 | return 1; |
93315ed6 AG |
798 | |
799 | switch(a->fields[i].type) { | |
3a6b9f85 DG |
800 | case AUDIT_SUBJ_USER: |
801 | case AUDIT_SUBJ_ROLE: | |
802 | case AUDIT_SUBJ_TYPE: | |
803 | case AUDIT_SUBJ_SEN: | |
804 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
805 | case AUDIT_OBJ_USER: |
806 | case AUDIT_OBJ_ROLE: | |
807 | case AUDIT_OBJ_TYPE: | |
808 | case AUDIT_OBJ_LEV_LOW: | |
809 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
810 | if (strcmp(a->fields[i].se_str, b->fields[i].se_str)) |
811 | return 1; | |
812 | break; | |
f368c07d AG |
813 | case AUDIT_WATCH: |
814 | if (strcmp(a->watch->path, b->watch->path)) | |
815 | return 1; | |
816 | break; | |
74c3cbe3 AV |
817 | case AUDIT_DIR: |
818 | if (strcmp(audit_tree_path(a->tree), | |
819 | audit_tree_path(b->tree))) | |
820 | return 1; | |
821 | break; | |
5adc8a6a AG |
822 | case AUDIT_FILTERKEY: |
823 | /* both filterkeys exist based on above type compare */ | |
824 | if (strcmp(a->filterkey, b->filterkey)) | |
825 | return 1; | |
826 | break; | |
93315ed6 AG |
827 | default: |
828 | if (a->fields[i].val != b->fields[i].val) | |
829 | return 1; | |
830 | } | |
fe7752ba DW |
831 | } |
832 | ||
833 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
834 | if (a->mask[i] != b->mask[i]) | |
835 | return 1; | |
836 | ||
837 | return 0; | |
838 | } | |
839 | ||
f368c07d AG |
840 | /* Duplicate the given audit watch. The new watch's rules list is initialized |
841 | * to an empty list and wlist is undefined. */ | |
842 | static struct audit_watch *audit_dupe_watch(struct audit_watch *old) | |
843 | { | |
844 | char *path; | |
845 | struct audit_watch *new; | |
846 | ||
847 | path = kstrdup(old->path, GFP_KERNEL); | |
848 | if (unlikely(!path)) | |
849 | return ERR_PTR(-ENOMEM); | |
850 | ||
851 | new = audit_init_watch(path); | |
852 | if (unlikely(IS_ERR(new))) { | |
853 | kfree(path); | |
854 | goto out; | |
855 | } | |
856 | ||
857 | new->dev = old->dev; | |
858 | new->ino = old->ino; | |
859 | get_inotify_watch(&old->parent->wdata); | |
860 | new->parent = old->parent; | |
861 | ||
862 | out: | |
863 | return new; | |
864 | } | |
865 | ||
3dc7e315 DG |
866 | /* Duplicate selinux field information. The se_rule is opaque, so must be |
867 | * re-initialized. */ | |
868 | static inline int audit_dupe_selinux_field(struct audit_field *df, | |
869 | struct audit_field *sf) | |
870 | { | |
871 | int ret = 0; | |
872 | char *se_str; | |
873 | ||
874 | /* our own copy of se_str */ | |
875 | se_str = kstrdup(sf->se_str, GFP_KERNEL); | |
3e1fbd12 AM |
876 | if (unlikely(!se_str)) |
877 | return -ENOMEM; | |
3dc7e315 DG |
878 | df->se_str = se_str; |
879 | ||
880 | /* our own (refreshed) copy of se_rule */ | |
881 | ret = selinux_audit_rule_init(df->type, df->op, df->se_str, | |
882 | &df->se_rule); | |
883 | /* Keep currently invalid fields around in case they | |
884 | * become valid after a policy reload. */ | |
885 | if (ret == -EINVAL) { | |
886 | printk(KERN_WARNING "audit rule for selinux \'%s\' is " | |
887 | "invalid\n", df->se_str); | |
888 | ret = 0; | |
889 | } | |
890 | ||
891 | return ret; | |
892 | } | |
893 | ||
894 | /* Duplicate an audit rule. This will be a deep copy with the exception | |
895 | * of the watch - that pointer is carried over. The selinux specific fields | |
896 | * will be updated in the copy. The point is to be able to replace the old | |
f368c07d AG |
897 | * rule with the new rule in the filterlist, then free the old rule. |
898 | * The rlist element is undefined; list manipulations are handled apart from | |
899 | * the initial copy. */ | |
900 | static struct audit_entry *audit_dupe_rule(struct audit_krule *old, | |
901 | struct audit_watch *watch) | |
3dc7e315 DG |
902 | { |
903 | u32 fcount = old->field_count; | |
904 | struct audit_entry *entry; | |
905 | struct audit_krule *new; | |
5adc8a6a | 906 | char *fk; |
3dc7e315 DG |
907 | int i, err = 0; |
908 | ||
909 | entry = audit_init_entry(fcount); | |
910 | if (unlikely(!entry)) | |
911 | return ERR_PTR(-ENOMEM); | |
912 | ||
913 | new = &entry->rule; | |
914 | new->vers_ops = old->vers_ops; | |
915 | new->flags = old->flags; | |
916 | new->listnr = old->listnr; | |
917 | new->action = old->action; | |
918 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
919 | new->mask[i] = old->mask[i]; | |
920 | new->buflen = old->buflen; | |
f368c07d AG |
921 | new->inode_f = old->inode_f; |
922 | new->watch = NULL; | |
3dc7e315 | 923 | new->field_count = old->field_count; |
74c3cbe3 AV |
924 | /* |
925 | * note that we are OK with not refcounting here; audit_match_tree() | |
926 | * never dereferences tree and we can't get false positives there | |
927 | * since we'd have to have rule gone from the list *and* removed | |
928 | * before the chunks found by lookup had been allocated, i.e. before | |
929 | * the beginning of list scan. | |
930 | */ | |
931 | new->tree = old->tree; | |
3dc7e315 DG |
932 | memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount); |
933 | ||
934 | /* deep copy this information, updating the se_rule fields, because | |
935 | * the originals will all be freed when the old rule is freed. */ | |
936 | for (i = 0; i < fcount; i++) { | |
937 | switch (new->fields[i].type) { | |
3a6b9f85 DG |
938 | case AUDIT_SUBJ_USER: |
939 | case AUDIT_SUBJ_ROLE: | |
940 | case AUDIT_SUBJ_TYPE: | |
941 | case AUDIT_SUBJ_SEN: | |
942 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
943 | case AUDIT_OBJ_USER: |
944 | case AUDIT_OBJ_ROLE: | |
945 | case AUDIT_OBJ_TYPE: | |
946 | case AUDIT_OBJ_LEV_LOW: | |
947 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
948 | err = audit_dupe_selinux_field(&new->fields[i], |
949 | &old->fields[i]); | |
5adc8a6a AG |
950 | break; |
951 | case AUDIT_FILTERKEY: | |
952 | fk = kstrdup(old->filterkey, GFP_KERNEL); | |
953 | if (unlikely(!fk)) | |
954 | err = -ENOMEM; | |
955 | else | |
956 | new->filterkey = fk; | |
3dc7e315 DG |
957 | } |
958 | if (err) { | |
959 | audit_free_rule(entry); | |
960 | return ERR_PTR(err); | |
961 | } | |
962 | } | |
963 | ||
f368c07d AG |
964 | if (watch) { |
965 | audit_get_watch(watch); | |
966 | new->watch = watch; | |
967 | } | |
968 | ||
3dc7e315 DG |
969 | return entry; |
970 | } | |
971 | ||
f368c07d AG |
972 | /* Update inode info in audit rules based on filesystem event. */ |
973 | static void audit_update_watch(struct audit_parent *parent, | |
974 | const char *dname, dev_t dev, | |
975 | unsigned long ino, unsigned invalidating) | |
976 | { | |
977 | struct audit_watch *owatch, *nwatch, *nextw; | |
978 | struct audit_krule *r, *nextr; | |
979 | struct audit_entry *oentry, *nentry; | |
f368c07d AG |
980 | |
981 | mutex_lock(&audit_filter_mutex); | |
982 | list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) { | |
9c937dcc | 983 | if (audit_compare_dname_path(dname, owatch->path, NULL)) |
f368c07d AG |
984 | continue; |
985 | ||
986 | /* If the update involves invalidating rules, do the inode-based | |
987 | * filtering now, so we don't omit records. */ | |
7b018b28 | 988 | if (invalidating && current->audit_context && |
f368c07d AG |
989 | audit_filter_inodes(current, current->audit_context) == AUDIT_RECORD_CONTEXT) |
990 | audit_set_auditable(current->audit_context); | |
991 | ||
992 | nwatch = audit_dupe_watch(owatch); | |
993 | if (unlikely(IS_ERR(nwatch))) { | |
994 | mutex_unlock(&audit_filter_mutex); | |
995 | audit_panic("error updating watch, skipping"); | |
996 | return; | |
997 | } | |
998 | nwatch->dev = dev; | |
999 | nwatch->ino = ino; | |
1000 | ||
1001 | list_for_each_entry_safe(r, nextr, &owatch->rules, rlist) { | |
1002 | ||
1003 | oentry = container_of(r, struct audit_entry, rule); | |
1004 | list_del(&oentry->rule.rlist); | |
1005 | list_del_rcu(&oentry->list); | |
1006 | ||
1007 | nentry = audit_dupe_rule(&oentry->rule, nwatch); | |
1008 | if (unlikely(IS_ERR(nentry))) | |
1009 | audit_panic("error updating watch, removing"); | |
1010 | else { | |
1011 | int h = audit_hash_ino((u32)ino); | |
1012 | list_add(&nentry->rule.rlist, &nwatch->rules); | |
1013 | list_add_rcu(&nentry->list, &audit_inode_hash[h]); | |
1014 | } | |
1015 | ||
1016 | call_rcu(&oentry->rcu, audit_free_rule_rcu); | |
1017 | } | |
1018 | ||
1a6b9f23 EP |
1019 | if (audit_enabled) { |
1020 | struct audit_buffer *ab; | |
1021 | ab = audit_log_start(NULL, GFP_KERNEL, | |
1022 | AUDIT_CONFIG_CHANGE); | |
1023 | audit_log_format(ab, | |
1024 | "op=updated rules specifying path="); | |
1025 | audit_log_untrustedstring(ab, owatch->path); | |
1026 | audit_log_format(ab, " with dev=%u ino=%lu\n", | |
1027 | dev, ino); | |
1028 | audit_log_format(ab, " list=%d res=1", r->listnr); | |
1029 | audit_log_end(ab); | |
1030 | } | |
f368c07d AG |
1031 | audit_remove_watch(owatch); |
1032 | goto add_watch_to_parent; /* event applies to a single watch */ | |
1033 | } | |
1034 | mutex_unlock(&audit_filter_mutex); | |
1035 | return; | |
1036 | ||
1037 | add_watch_to_parent: | |
1038 | list_add(&nwatch->wlist, &parent->watches); | |
1039 | mutex_unlock(&audit_filter_mutex); | |
1040 | return; | |
1041 | } | |
1042 | ||
1043 | /* Remove all watches & rules associated with a parent that is going away. */ | |
1044 | static void audit_remove_parent_watches(struct audit_parent *parent) | |
1045 | { | |
1046 | struct audit_watch *w, *nextw; | |
1047 | struct audit_krule *r, *nextr; | |
1048 | struct audit_entry *e; | |
1049 | ||
1050 | mutex_lock(&audit_filter_mutex); | |
1051 | parent->flags |= AUDIT_PARENT_INVALID; | |
1052 | list_for_each_entry_safe(w, nextw, &parent->watches, wlist) { | |
1053 | list_for_each_entry_safe(r, nextr, &w->rules, rlist) { | |
1054 | e = container_of(r, struct audit_entry, rule); | |
1a6b9f23 EP |
1055 | if (audit_enabled) { |
1056 | struct audit_buffer *ab; | |
1057 | ab = audit_log_start(NULL, GFP_KERNEL, | |
1058 | AUDIT_CONFIG_CHANGE); | |
1059 | audit_log_format(ab, "op=remove rule path="); | |
1060 | audit_log_untrustedstring(ab, w->path); | |
1061 | if (r->filterkey) { | |
1062 | audit_log_format(ab, " key="); | |
1063 | audit_log_untrustedstring(ab, | |
1064 | r->filterkey); | |
1065 | } else | |
1066 | audit_log_format(ab, " key=(null)"); | |
1067 | audit_log_format(ab, " list=%d res=1", | |
1068 | r->listnr); | |
1069 | audit_log_end(ab); | |
1070 | } | |
f368c07d AG |
1071 | list_del(&r->rlist); |
1072 | list_del_rcu(&e->list); | |
1073 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
f368c07d AG |
1074 | } |
1075 | audit_remove_watch(w); | |
1076 | } | |
1077 | mutex_unlock(&audit_filter_mutex); | |
1078 | } | |
1079 | ||
1080 | /* Unregister inotify watches for parents on in_list. | |
1081 | * Generates an IN_IGNORED event. */ | |
1082 | static void audit_inotify_unregister(struct list_head *in_list) | |
1083 | { | |
1084 | struct audit_parent *p, *n; | |
1085 | ||
1086 | list_for_each_entry_safe(p, n, in_list, ilist) { | |
1087 | list_del(&p->ilist); | |
1088 | inotify_rm_watch(audit_ih, &p->wdata); | |
1089 | /* the put matching the get in audit_do_del_rule() */ | |
1090 | put_inotify_watch(&p->wdata); | |
1091 | } | |
1092 | } | |
1093 | ||
1094 | /* Find an existing audit rule. | |
1095 | * Caller must hold audit_filter_mutex to prevent stale rule data. */ | |
1096 | static struct audit_entry *audit_find_rule(struct audit_entry *entry, | |
1097 | struct list_head *list) | |
1098 | { | |
1099 | struct audit_entry *e, *found = NULL; | |
1100 | int h; | |
1101 | ||
1102 | if (entry->rule.watch) { | |
1103 | /* we don't know the inode number, so must walk entire hash */ | |
1104 | for (h = 0; h < AUDIT_INODE_BUCKETS; h++) { | |
1105 | list = &audit_inode_hash[h]; | |
1106 | list_for_each_entry(e, list, list) | |
1107 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
1108 | found = e; | |
1109 | goto out; | |
1110 | } | |
1111 | } | |
1112 | goto out; | |
1113 | } | |
1114 | ||
1115 | list_for_each_entry(e, list, list) | |
1116 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
1117 | found = e; | |
1118 | goto out; | |
1119 | } | |
1120 | ||
1121 | out: | |
1122 | return found; | |
1123 | } | |
1124 | ||
1125 | /* Get path information necessary for adding watches. */ | |
1126 | static int audit_get_nd(char *path, struct nameidata **ndp, | |
1127 | struct nameidata **ndw) | |
1128 | { | |
1129 | struct nameidata *ndparent, *ndwatch; | |
1130 | int err; | |
1131 | ||
1132 | ndparent = kmalloc(sizeof(*ndparent), GFP_KERNEL); | |
1133 | if (unlikely(!ndparent)) | |
1134 | return -ENOMEM; | |
1135 | ||
1136 | ndwatch = kmalloc(sizeof(*ndwatch), GFP_KERNEL); | |
1137 | if (unlikely(!ndwatch)) { | |
1138 | kfree(ndparent); | |
1139 | return -ENOMEM; | |
1140 | } | |
1141 | ||
1142 | err = path_lookup(path, LOOKUP_PARENT, ndparent); | |
1143 | if (err) { | |
1144 | kfree(ndparent); | |
1145 | kfree(ndwatch); | |
1146 | return err; | |
1147 | } | |
1148 | ||
1149 | err = path_lookup(path, 0, ndwatch); | |
1150 | if (err) { | |
1151 | kfree(ndwatch); | |
1152 | ndwatch = NULL; | |
1153 | } | |
1154 | ||
1155 | *ndp = ndparent; | |
1156 | *ndw = ndwatch; | |
1157 | ||
1158 | return 0; | |
1159 | } | |
1160 | ||
1161 | /* Release resources used for watch path information. */ | |
1162 | static void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw) | |
1163 | { | |
1164 | if (ndp) { | |
1d957f9b | 1165 | path_put(&ndp->path); |
f368c07d AG |
1166 | kfree(ndp); |
1167 | } | |
1168 | if (ndw) { | |
1d957f9b | 1169 | path_put(&ndw->path); |
f368c07d AG |
1170 | kfree(ndw); |
1171 | } | |
1172 | } | |
1173 | ||
1174 | /* Associate the given rule with an existing parent inotify_watch. | |
1175 | * Caller must hold audit_filter_mutex. */ | |
1176 | static void audit_add_to_parent(struct audit_krule *krule, | |
1177 | struct audit_parent *parent) | |
1178 | { | |
1179 | struct audit_watch *w, *watch = krule->watch; | |
1180 | int watch_found = 0; | |
1181 | ||
1182 | list_for_each_entry(w, &parent->watches, wlist) { | |
1183 | if (strcmp(watch->path, w->path)) | |
1184 | continue; | |
1185 | ||
1186 | watch_found = 1; | |
1187 | ||
1188 | /* put krule's and initial refs to temporary watch */ | |
1189 | audit_put_watch(watch); | |
1190 | audit_put_watch(watch); | |
1191 | ||
1192 | audit_get_watch(w); | |
1193 | krule->watch = watch = w; | |
1194 | break; | |
1195 | } | |
1196 | ||
1197 | if (!watch_found) { | |
1198 | get_inotify_watch(&parent->wdata); | |
1199 | watch->parent = parent; | |
1200 | ||
1201 | list_add(&watch->wlist, &parent->watches); | |
1202 | } | |
1203 | list_add(&krule->rlist, &watch->rules); | |
1204 | } | |
1205 | ||
1206 | /* Find a matching watch entry, or add this one. | |
1207 | * Caller must hold audit_filter_mutex. */ | |
1208 | static int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, | |
1209 | struct nameidata *ndw) | |
1210 | { | |
1211 | struct audit_watch *watch = krule->watch; | |
1212 | struct inotify_watch *i_watch; | |
1213 | struct audit_parent *parent; | |
1214 | int ret = 0; | |
1215 | ||
1216 | /* update watch filter fields */ | |
1217 | if (ndw) { | |
4ac91378 JB |
1218 | watch->dev = ndw->path.dentry->d_inode->i_sb->s_dev; |
1219 | watch->ino = ndw->path.dentry->d_inode->i_ino; | |
f368c07d AG |
1220 | } |
1221 | ||
1222 | /* The audit_filter_mutex must not be held during inotify calls because | |
1223 | * we hold it during inotify event callback processing. If an existing | |
1224 | * inotify watch is found, inotify_find_watch() grabs a reference before | |
1225 | * returning. | |
1226 | */ | |
1227 | mutex_unlock(&audit_filter_mutex); | |
1228 | ||
4ac91378 JB |
1229 | if (inotify_find_watch(audit_ih, ndp->path.dentry->d_inode, |
1230 | &i_watch) < 0) { | |
f368c07d AG |
1231 | parent = audit_init_parent(ndp); |
1232 | if (IS_ERR(parent)) { | |
1233 | /* caller expects mutex locked */ | |
1234 | mutex_lock(&audit_filter_mutex); | |
1235 | return PTR_ERR(parent); | |
1236 | } | |
1237 | } else | |
1238 | parent = container_of(i_watch, struct audit_parent, wdata); | |
1239 | ||
1240 | mutex_lock(&audit_filter_mutex); | |
1241 | ||
1242 | /* parent was moved before we took audit_filter_mutex */ | |
1243 | if (parent->flags & AUDIT_PARENT_INVALID) | |
1244 | ret = -ENOENT; | |
1245 | else | |
1246 | audit_add_to_parent(krule, parent); | |
1247 | ||
1248 | /* match get in audit_init_parent or inotify_find_watch */ | |
1249 | put_inotify_watch(&parent->wdata); | |
1250 | return ret; | |
1251 | } | |
1252 | ||
1253 | /* Add rule to given filterlist if not a duplicate. */ | |
93315ed6 | 1254 | static inline int audit_add_rule(struct audit_entry *entry, |
f368c07d | 1255 | struct list_head *list) |
fe7752ba | 1256 | { |
93315ed6 | 1257 | struct audit_entry *e; |
f368c07d AG |
1258 | struct audit_field *inode_f = entry->rule.inode_f; |
1259 | struct audit_watch *watch = entry->rule.watch; | |
74c3cbe3 | 1260 | struct audit_tree *tree = entry->rule.tree; |
6f686d3d JG |
1261 | struct nameidata *ndp = NULL, *ndw = NULL; |
1262 | int h, err; | |
471a5c7c AV |
1263 | #ifdef CONFIG_AUDITSYSCALL |
1264 | int dont_count = 0; | |
1265 | ||
1266 | /* If either of these, don't count towards total */ | |
1267 | if (entry->rule.listnr == AUDIT_FILTER_USER || | |
1268 | entry->rule.listnr == AUDIT_FILTER_TYPE) | |
1269 | dont_count = 1; | |
1270 | #endif | |
f368c07d AG |
1271 | |
1272 | if (inode_f) { | |
1273 | h = audit_hash_ino(inode_f->val); | |
1274 | list = &audit_inode_hash[h]; | |
1275 | } | |
1276 | ||
1277 | mutex_lock(&audit_filter_mutex); | |
1278 | e = audit_find_rule(entry, list); | |
1279 | mutex_unlock(&audit_filter_mutex); | |
1280 | if (e) { | |
1281 | err = -EEXIST; | |
74c3cbe3 AV |
1282 | /* normally audit_add_tree_rule() will free it on failure */ |
1283 | if (tree) | |
1284 | audit_put_tree(tree); | |
f368c07d AG |
1285 | goto error; |
1286 | } | |
fe7752ba | 1287 | |
f368c07d AG |
1288 | /* Avoid calling path_lookup under audit_filter_mutex. */ |
1289 | if (watch) { | |
1290 | err = audit_get_nd(watch->path, &ndp, &ndw); | |
1291 | if (err) | |
1292 | goto error; | |
f368c07d AG |
1293 | } |
1294 | ||
1295 | mutex_lock(&audit_filter_mutex); | |
1296 | if (watch) { | |
1297 | /* audit_filter_mutex is dropped and re-taken during this call */ | |
1298 | err = audit_add_watch(&entry->rule, ndp, ndw); | |
1299 | if (err) { | |
1300 | mutex_unlock(&audit_filter_mutex); | |
1301 | goto error; | |
1302 | } | |
1303 | h = audit_hash_ino((u32)watch->ino); | |
1304 | list = &audit_inode_hash[h]; | |
fe7752ba | 1305 | } |
74c3cbe3 AV |
1306 | if (tree) { |
1307 | err = audit_add_tree_rule(&entry->rule); | |
1308 | if (err) { | |
1309 | mutex_unlock(&audit_filter_mutex); | |
1310 | goto error; | |
1311 | } | |
1312 | } | |
fe7752ba | 1313 | |
fe7752ba | 1314 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
fe7752ba | 1315 | list_add_rcu(&entry->list, list); |
6a2bceec | 1316 | entry->rule.flags &= ~AUDIT_FILTER_PREPEND; |
fe7752ba DW |
1317 | } else { |
1318 | list_add_tail_rcu(&entry->list, list); | |
1319 | } | |
471a5c7c AV |
1320 | #ifdef CONFIG_AUDITSYSCALL |
1321 | if (!dont_count) | |
1322 | audit_n_rules++; | |
e54dc243 AG |
1323 | |
1324 | if (!audit_match_signal(entry)) | |
1325 | audit_signals++; | |
471a5c7c | 1326 | #endif |
f368c07d | 1327 | mutex_unlock(&audit_filter_mutex); |
fe7752ba | 1328 | |
6f686d3d | 1329 | audit_put_nd(ndp, ndw); /* NULL args OK */ |
f368c07d AG |
1330 | return 0; |
1331 | ||
1332 | error: | |
6f686d3d | 1333 | audit_put_nd(ndp, ndw); /* NULL args OK */ |
f368c07d AG |
1334 | if (watch) |
1335 | audit_put_watch(watch); /* tmp watch, matches initial get */ | |
1336 | return err; | |
fe7752ba DW |
1337 | } |
1338 | ||
f368c07d | 1339 | /* Remove an existing rule from filterlist. */ |
93315ed6 | 1340 | static inline int audit_del_rule(struct audit_entry *entry, |
fe7752ba DW |
1341 | struct list_head *list) |
1342 | { | |
1343 | struct audit_entry *e; | |
f368c07d AG |
1344 | struct audit_field *inode_f = entry->rule.inode_f; |
1345 | struct audit_watch *watch, *tmp_watch = entry->rule.watch; | |
74c3cbe3 | 1346 | struct audit_tree *tree = entry->rule.tree; |
f368c07d AG |
1347 | LIST_HEAD(inotify_list); |
1348 | int h, ret = 0; | |
471a5c7c AV |
1349 | #ifdef CONFIG_AUDITSYSCALL |
1350 | int dont_count = 0; | |
1351 | ||
1352 | /* If either of these, don't count towards total */ | |
1353 | if (entry->rule.listnr == AUDIT_FILTER_USER || | |
1354 | entry->rule.listnr == AUDIT_FILTER_TYPE) | |
1355 | dont_count = 1; | |
1356 | #endif | |
f368c07d AG |
1357 | |
1358 | if (inode_f) { | |
1359 | h = audit_hash_ino(inode_f->val); | |
1360 | list = &audit_inode_hash[h]; | |
1361 | } | |
fe7752ba | 1362 | |
f368c07d AG |
1363 | mutex_lock(&audit_filter_mutex); |
1364 | e = audit_find_rule(entry, list); | |
1365 | if (!e) { | |
1366 | mutex_unlock(&audit_filter_mutex); | |
1367 | ret = -ENOENT; | |
1368 | goto out; | |
1369 | } | |
1370 | ||
1371 | watch = e->rule.watch; | |
1372 | if (watch) { | |
1373 | struct audit_parent *parent = watch->parent; | |
1374 | ||
1375 | list_del(&e->rule.rlist); | |
1376 | ||
1377 | if (list_empty(&watch->rules)) { | |
1378 | audit_remove_watch(watch); | |
1379 | ||
1380 | if (list_empty(&parent->watches)) { | |
1381 | /* Put parent on the inotify un-registration | |
1382 | * list. Grab a reference before releasing | |
1383 | * audit_filter_mutex, to be released in | |
1384 | * audit_inotify_unregister(). */ | |
1385 | list_add(&parent->ilist, &inotify_list); | |
1386 | get_inotify_watch(&parent->wdata); | |
1387 | } | |
fe7752ba DW |
1388 | } |
1389 | } | |
f368c07d | 1390 | |
74c3cbe3 AV |
1391 | if (e->rule.tree) |
1392 | audit_remove_tree_rule(&e->rule); | |
1393 | ||
f368c07d AG |
1394 | list_del_rcu(&e->list); |
1395 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
1396 | ||
471a5c7c AV |
1397 | #ifdef CONFIG_AUDITSYSCALL |
1398 | if (!dont_count) | |
1399 | audit_n_rules--; | |
e54dc243 AG |
1400 | |
1401 | if (!audit_match_signal(entry)) | |
1402 | audit_signals--; | |
471a5c7c | 1403 | #endif |
f368c07d AG |
1404 | mutex_unlock(&audit_filter_mutex); |
1405 | ||
1406 | if (!list_empty(&inotify_list)) | |
1407 | audit_inotify_unregister(&inotify_list); | |
1408 | ||
1409 | out: | |
1410 | if (tmp_watch) | |
1411 | audit_put_watch(tmp_watch); /* match initial get */ | |
74c3cbe3 AV |
1412 | if (tree) |
1413 | audit_put_tree(tree); /* that's the temporary one */ | |
f368c07d AG |
1414 | |
1415 | return ret; | |
fe7752ba DW |
1416 | } |
1417 | ||
93315ed6 AG |
1418 | /* List rules using struct audit_rule. Exists for backward |
1419 | * compatibility with userspace. */ | |
9044e6bc | 1420 | static void audit_list(int pid, int seq, struct sk_buff_head *q) |
fe7752ba | 1421 | { |
9044e6bc | 1422 | struct sk_buff *skb; |
fe7752ba DW |
1423 | struct audit_entry *entry; |
1424 | int i; | |
1425 | ||
f368c07d AG |
1426 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1427 | * iterator to sync with list writers. */ | |
fe7752ba | 1428 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
93315ed6 AG |
1429 | list_for_each_entry(entry, &audit_filter_list[i], list) { |
1430 | struct audit_rule *rule; | |
1431 | ||
1432 | rule = audit_krule_to_rule(&entry->rule); | |
1433 | if (unlikely(!rule)) | |
1434 | break; | |
9044e6bc | 1435 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, |
93315ed6 | 1436 | rule, sizeof(*rule)); |
9044e6bc AV |
1437 | if (skb) |
1438 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1439 | kfree(rule); |
1440 | } | |
fe7752ba | 1441 | } |
f368c07d AG |
1442 | for (i = 0; i < AUDIT_INODE_BUCKETS; i++) { |
1443 | list_for_each_entry(entry, &audit_inode_hash[i], list) { | |
1444 | struct audit_rule *rule; | |
1445 | ||
1446 | rule = audit_krule_to_rule(&entry->rule); | |
1447 | if (unlikely(!rule)) | |
1448 | break; | |
1449 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, | |
1450 | rule, sizeof(*rule)); | |
1451 | if (skb) | |
1452 | skb_queue_tail(q, skb); | |
1453 | kfree(rule); | |
1454 | } | |
1455 | } | |
9044e6bc AV |
1456 | skb = audit_make_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0); |
1457 | if (skb) | |
1458 | skb_queue_tail(q, skb); | |
fe7752ba DW |
1459 | } |
1460 | ||
93315ed6 | 1461 | /* List rules using struct audit_rule_data. */ |
9044e6bc | 1462 | static void audit_list_rules(int pid, int seq, struct sk_buff_head *q) |
93315ed6 | 1463 | { |
9044e6bc | 1464 | struct sk_buff *skb; |
93315ed6 AG |
1465 | struct audit_entry *e; |
1466 | int i; | |
1467 | ||
f368c07d AG |
1468 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1469 | * iterator to sync with list writers. */ | |
93315ed6 AG |
1470 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
1471 | list_for_each_entry(e, &audit_filter_list[i], list) { | |
1472 | struct audit_rule_data *data; | |
1473 | ||
1474 | data = audit_krule_to_data(&e->rule); | |
1475 | if (unlikely(!data)) | |
1476 | break; | |
9044e6bc | 1477 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, |
f368c07d AG |
1478 | data, sizeof(*data) + data->buflen); |
1479 | if (skb) | |
1480 | skb_queue_tail(q, skb); | |
1481 | kfree(data); | |
1482 | } | |
1483 | } | |
1484 | for (i=0; i< AUDIT_INODE_BUCKETS; i++) { | |
1485 | list_for_each_entry(e, &audit_inode_hash[i], list) { | |
1486 | struct audit_rule_data *data; | |
1487 | ||
1488 | data = audit_krule_to_data(&e->rule); | |
1489 | if (unlikely(!data)) | |
1490 | break; | |
1491 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, | |
1492 | data, sizeof(*data) + data->buflen); | |
9044e6bc AV |
1493 | if (skb) |
1494 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1495 | kfree(data); |
1496 | } | |
1497 | } | |
9044e6bc AV |
1498 | skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); |
1499 | if (skb) | |
1500 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1501 | } |
1502 | ||
5adc8a6a AG |
1503 | /* Log rule additions and removals */ |
1504 | static void audit_log_rule_change(uid_t loginuid, u32 sid, char *action, | |
1505 | struct audit_krule *rule, int res) | |
1506 | { | |
1507 | struct audit_buffer *ab; | |
1508 | ||
1a6b9f23 EP |
1509 | if (!audit_enabled) |
1510 | return; | |
1511 | ||
5adc8a6a AG |
1512 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
1513 | if (!ab) | |
1514 | return; | |
1515 | audit_log_format(ab, "auid=%u", loginuid); | |
1516 | if (sid) { | |
1517 | char *ctx = NULL; | |
1518 | u32 len; | |
2a862b32 | 1519 | if (security_secid_to_secctx(sid, &ctx, &len)) |
5adc8a6a | 1520 | audit_log_format(ab, " ssid=%u", sid); |
2a862b32 | 1521 | else { |
5adc8a6a | 1522 | audit_log_format(ab, " subj=%s", ctx); |
2a862b32 AD |
1523 | security_release_secctx(ctx, len); |
1524 | } | |
5adc8a6a | 1525 | } |
a17b4ad7 | 1526 | audit_log_format(ab, " op=%s rule key=", action); |
5adc8a6a AG |
1527 | if (rule->filterkey) |
1528 | audit_log_untrustedstring(ab, rule->filterkey); | |
1529 | else | |
1530 | audit_log_format(ab, "(null)"); | |
1531 | audit_log_format(ab, " list=%d res=%d", rule->listnr, res); | |
1532 | audit_log_end(ab); | |
1533 | } | |
1534 | ||
fe7752ba DW |
1535 | /** |
1536 | * audit_receive_filter - apply all rules to the specified message type | |
1537 | * @type: audit message type | |
1538 | * @pid: target pid for netlink audit messages | |
1539 | * @uid: target uid for netlink audit messages | |
1540 | * @seq: netlink audit message sequence (serial) number | |
1541 | * @data: payload data | |
93315ed6 | 1542 | * @datasz: size of payload data |
fe7752ba | 1543 | * @loginuid: loginuid of sender |
ce29b682 | 1544 | * @sid: SE Linux Security ID of sender |
fe7752ba DW |
1545 | */ |
1546 | int audit_receive_filter(int type, int pid, int uid, int seq, void *data, | |
ce29b682 | 1547 | size_t datasz, uid_t loginuid, u32 sid) |
fe7752ba DW |
1548 | { |
1549 | struct task_struct *tsk; | |
9044e6bc | 1550 | struct audit_netlink_list *dest; |
93315ed6 AG |
1551 | int err = 0; |
1552 | struct audit_entry *entry; | |
fe7752ba DW |
1553 | |
1554 | switch (type) { | |
1555 | case AUDIT_LIST: | |
93315ed6 | 1556 | case AUDIT_LIST_RULES: |
fe7752ba DW |
1557 | /* We can't just spew out the rules here because we might fill |
1558 | * the available socket buffer space and deadlock waiting for | |
1559 | * auditctl to read from it... which isn't ever going to | |
1560 | * happen if we're actually running in the context of auditctl | |
1561 | * trying to _send_ the stuff */ | |
9ce34218 | 1562 | |
9044e6bc | 1563 | dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); |
fe7752ba DW |
1564 | if (!dest) |
1565 | return -ENOMEM; | |
9044e6bc AV |
1566 | dest->pid = pid; |
1567 | skb_queue_head_init(&dest->q); | |
fe7752ba | 1568 | |
f368c07d | 1569 | mutex_lock(&audit_filter_mutex); |
93315ed6 | 1570 | if (type == AUDIT_LIST) |
9044e6bc | 1571 | audit_list(pid, seq, &dest->q); |
93315ed6 | 1572 | else |
9044e6bc | 1573 | audit_list_rules(pid, seq, &dest->q); |
f368c07d | 1574 | mutex_unlock(&audit_filter_mutex); |
9044e6bc AV |
1575 | |
1576 | tsk = kthread_run(audit_send_list, dest, "audit_send_list"); | |
fe7752ba | 1577 | if (IS_ERR(tsk)) { |
9044e6bc | 1578 | skb_queue_purge(&dest->q); |
fe7752ba DW |
1579 | kfree(dest); |
1580 | err = PTR_ERR(tsk); | |
1581 | } | |
1582 | break; | |
1583 | case AUDIT_ADD: | |
93315ed6 AG |
1584 | case AUDIT_ADD_RULE: |
1585 | if (type == AUDIT_ADD) | |
1586 | entry = audit_rule_to_entry(data); | |
1587 | else | |
1588 | entry = audit_data_to_entry(data, datasz); | |
1589 | if (IS_ERR(entry)) | |
1590 | return PTR_ERR(entry); | |
1591 | ||
1592 | err = audit_add_rule(entry, | |
1593 | &audit_filter_list[entry->rule.listnr]); | |
5adc8a6a | 1594 | audit_log_rule_change(loginuid, sid, "add", &entry->rule, !err); |
5d330108 AV |
1595 | |
1596 | if (err) | |
93315ed6 | 1597 | audit_free_rule(entry); |
fe7752ba DW |
1598 | break; |
1599 | case AUDIT_DEL: | |
93315ed6 AG |
1600 | case AUDIT_DEL_RULE: |
1601 | if (type == AUDIT_DEL) | |
1602 | entry = audit_rule_to_entry(data); | |
1603 | else | |
1604 | entry = audit_data_to_entry(data, datasz); | |
1605 | if (IS_ERR(entry)) | |
1606 | return PTR_ERR(entry); | |
1607 | ||
1608 | err = audit_del_rule(entry, | |
1609 | &audit_filter_list[entry->rule.listnr]); | |
5adc8a6a AG |
1610 | audit_log_rule_change(loginuid, sid, "remove", &entry->rule, |
1611 | !err); | |
5d330108 | 1612 | |
93315ed6 | 1613 | audit_free_rule(entry); |
fe7752ba DW |
1614 | break; |
1615 | default: | |
1616 | return -EINVAL; | |
1617 | } | |
1618 | ||
1619 | return err; | |
1620 | } | |
1621 | ||
1622 | int audit_comparator(const u32 left, const u32 op, const u32 right) | |
1623 | { | |
1624 | switch (op) { | |
1625 | case AUDIT_EQUAL: | |
1626 | return (left == right); | |
1627 | case AUDIT_NOT_EQUAL: | |
1628 | return (left != right); | |
1629 | case AUDIT_LESS_THAN: | |
1630 | return (left < right); | |
1631 | case AUDIT_LESS_THAN_OR_EQUAL: | |
1632 | return (left <= right); | |
1633 | case AUDIT_GREATER_THAN: | |
1634 | return (left > right); | |
1635 | case AUDIT_GREATER_THAN_OR_EQUAL: | |
1636 | return (left >= right); | |
74f2345b EP |
1637 | case AUDIT_BIT_MASK: |
1638 | return (left & right); | |
1639 | case AUDIT_BIT_TEST: | |
1640 | return ((left & right) == right); | |
fe7752ba | 1641 | } |
d9d9ec6e DK |
1642 | BUG(); |
1643 | return 0; | |
fe7752ba DW |
1644 | } |
1645 | ||
f368c07d AG |
1646 | /* Compare given dentry name with last component in given path, |
1647 | * return of 0 indicates a match. */ | |
9c937dcc AG |
1648 | int audit_compare_dname_path(const char *dname, const char *path, |
1649 | int *dirlen) | |
f368c07d AG |
1650 | { |
1651 | int dlen, plen; | |
1652 | const char *p; | |
1653 | ||
1654 | if (!dname || !path) | |
1655 | return 1; | |
1656 | ||
1657 | dlen = strlen(dname); | |
1658 | plen = strlen(path); | |
1659 | if (plen < dlen) | |
1660 | return 1; | |
1661 | ||
1662 | /* disregard trailing slashes */ | |
1663 | p = path + plen - 1; | |
1664 | while ((*p == '/') && (p > path)) | |
1665 | p--; | |
1666 | ||
1667 | /* find last path component */ | |
1668 | p = p - dlen + 1; | |
1669 | if (p < path) | |
1670 | return 1; | |
1671 | else if (p > path) { | |
1672 | if (*--p != '/') | |
1673 | return 1; | |
1674 | else | |
1675 | p++; | |
1676 | } | |
fe7752ba | 1677 | |
9c937dcc AG |
1678 | /* return length of path's directory component */ |
1679 | if (dirlen) | |
1680 | *dirlen = p - path; | |
f368c07d AG |
1681 | return strncmp(p, dname, dlen); |
1682 | } | |
fe7752ba DW |
1683 | |
1684 | static int audit_filter_user_rules(struct netlink_skb_parms *cb, | |
93315ed6 | 1685 | struct audit_krule *rule, |
fe7752ba DW |
1686 | enum audit_state *state) |
1687 | { | |
1688 | int i; | |
1689 | ||
1690 | for (i = 0; i < rule->field_count; i++) { | |
93315ed6 | 1691 | struct audit_field *f = &rule->fields[i]; |
fe7752ba DW |
1692 | int result = 0; |
1693 | ||
93315ed6 | 1694 | switch (f->type) { |
fe7752ba | 1695 | case AUDIT_PID: |
93315ed6 | 1696 | result = audit_comparator(cb->creds.pid, f->op, f->val); |
fe7752ba DW |
1697 | break; |
1698 | case AUDIT_UID: | |
93315ed6 | 1699 | result = audit_comparator(cb->creds.uid, f->op, f->val); |
fe7752ba DW |
1700 | break; |
1701 | case AUDIT_GID: | |
93315ed6 | 1702 | result = audit_comparator(cb->creds.gid, f->op, f->val); |
fe7752ba DW |
1703 | break; |
1704 | case AUDIT_LOGINUID: | |
93315ed6 | 1705 | result = audit_comparator(cb->loginuid, f->op, f->val); |
fe7752ba DW |
1706 | break; |
1707 | } | |
1708 | ||
1709 | if (!result) | |
1710 | return 0; | |
1711 | } | |
1712 | switch (rule->action) { | |
1713 | case AUDIT_NEVER: *state = AUDIT_DISABLED; break; | |
fe7752ba DW |
1714 | case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; |
1715 | } | |
1716 | return 1; | |
1717 | } | |
1718 | ||
1719 | int audit_filter_user(struct netlink_skb_parms *cb, int type) | |
1720 | { | |
11f57ced | 1721 | enum audit_state state = AUDIT_DISABLED; |
fe7752ba | 1722 | struct audit_entry *e; |
fe7752ba DW |
1723 | int ret = 1; |
1724 | ||
1725 | rcu_read_lock(); | |
1726 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { | |
1727 | if (audit_filter_user_rules(cb, &e->rule, &state)) { | |
1728 | if (state == AUDIT_DISABLED) | |
1729 | ret = 0; | |
1730 | break; | |
1731 | } | |
1732 | } | |
1733 | rcu_read_unlock(); | |
1734 | ||
1735 | return ret; /* Audit by default */ | |
1736 | } | |
1737 | ||
1738 | int audit_filter_type(int type) | |
1739 | { | |
1740 | struct audit_entry *e; | |
1741 | int result = 0; | |
9ce34218 | 1742 | |
fe7752ba DW |
1743 | rcu_read_lock(); |
1744 | if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE])) | |
1745 | goto unlock_and_return; | |
1746 | ||
1747 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE], | |
1748 | list) { | |
fe7752ba | 1749 | int i; |
93315ed6 AG |
1750 | for (i = 0; i < e->rule.field_count; i++) { |
1751 | struct audit_field *f = &e->rule.fields[i]; | |
1752 | if (f->type == AUDIT_MSGTYPE) { | |
1753 | result = audit_comparator(type, f->op, f->val); | |
fe7752ba DW |
1754 | if (!result) |
1755 | break; | |
1756 | } | |
1757 | } | |
1758 | if (result) | |
1759 | goto unlock_and_return; | |
1760 | } | |
1761 | unlock_and_return: | |
1762 | rcu_read_unlock(); | |
1763 | return result; | |
1764 | } | |
3dc7e315 DG |
1765 | |
1766 | /* Check to see if the rule contains any selinux fields. Returns 1 if there | |
1767 | are selinux fields specified in the rule, 0 otherwise. */ | |
1768 | static inline int audit_rule_has_selinux(struct audit_krule *rule) | |
1769 | { | |
1770 | int i; | |
1771 | ||
1772 | for (i = 0; i < rule->field_count; i++) { | |
1773 | struct audit_field *f = &rule->fields[i]; | |
1774 | switch (f->type) { | |
3a6b9f85 DG |
1775 | case AUDIT_SUBJ_USER: |
1776 | case AUDIT_SUBJ_ROLE: | |
1777 | case AUDIT_SUBJ_TYPE: | |
1778 | case AUDIT_SUBJ_SEN: | |
1779 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
1780 | case AUDIT_OBJ_USER: |
1781 | case AUDIT_OBJ_ROLE: | |
1782 | case AUDIT_OBJ_TYPE: | |
1783 | case AUDIT_OBJ_LEV_LOW: | |
1784 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
1785 | return 1; |
1786 | } | |
1787 | } | |
1788 | ||
1789 | return 0; | |
1790 | } | |
1791 | ||
1792 | /* This function will re-initialize the se_rule field of all applicable rules. | |
1793 | * It will traverse the filter lists serarching for rules that contain selinux | |
1794 | * specific filter fields. When such a rule is found, it is copied, the | |
1795 | * selinux field is re-initialized, and the old rule is replaced with the | |
1796 | * updated rule. */ | |
1797 | int selinux_audit_rule_update(void) | |
1798 | { | |
1799 | struct audit_entry *entry, *n, *nentry; | |
f368c07d | 1800 | struct audit_watch *watch; |
74c3cbe3 | 1801 | struct audit_tree *tree; |
3dc7e315 DG |
1802 | int i, err = 0; |
1803 | ||
f368c07d AG |
1804 | /* audit_filter_mutex synchronizes the writers */ |
1805 | mutex_lock(&audit_filter_mutex); | |
3dc7e315 DG |
1806 | |
1807 | for (i = 0; i < AUDIT_NR_FILTERS; i++) { | |
1808 | list_for_each_entry_safe(entry, n, &audit_filter_list[i], list) { | |
1809 | if (!audit_rule_has_selinux(&entry->rule)) | |
1810 | continue; | |
1811 | ||
f368c07d | 1812 | watch = entry->rule.watch; |
74c3cbe3 | 1813 | tree = entry->rule.tree; |
f368c07d | 1814 | nentry = audit_dupe_rule(&entry->rule, watch); |
3dc7e315 DG |
1815 | if (unlikely(IS_ERR(nentry))) { |
1816 | /* save the first error encountered for the | |
1817 | * return value */ | |
1818 | if (!err) | |
1819 | err = PTR_ERR(nentry); | |
1820 | audit_panic("error updating selinux filters"); | |
f368c07d AG |
1821 | if (watch) |
1822 | list_del(&entry->rule.rlist); | |
3dc7e315 DG |
1823 | list_del_rcu(&entry->list); |
1824 | } else { | |
f368c07d AG |
1825 | if (watch) { |
1826 | list_add(&nentry->rule.rlist, | |
1827 | &watch->rules); | |
1828 | list_del(&entry->rule.rlist); | |
74c3cbe3 AV |
1829 | } else if (tree) |
1830 | list_replace_init(&entry->rule.rlist, | |
1831 | &nentry->rule.rlist); | |
3dc7e315 DG |
1832 | list_replace_rcu(&entry->list, &nentry->list); |
1833 | } | |
1834 | call_rcu(&entry->rcu, audit_free_rule_rcu); | |
1835 | } | |
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 | } |