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 | ||
f952d10f RGB |
22 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
23 | ||
fe7752ba DW |
24 | #include <linux/kernel.h> |
25 | #include <linux/audit.h> | |
26 | #include <linux/kthread.h> | |
f368c07d AG |
27 | #include <linux/mutex.h> |
28 | #include <linux/fs.h> | |
29 | #include <linux/namei.h> | |
fe7752ba | 30 | #include <linux/netlink.h> |
f368c07d | 31 | #include <linux/sched.h> |
5a0e3ad6 | 32 | #include <linux/slab.h> |
2a862b32 | 33 | #include <linux/security.h> |
48095d99 | 34 | #include <net/net_namespace.h> |
6f285b19 | 35 | #include <net/sock.h> |
fe7752ba DW |
36 | #include "audit.h" |
37 | ||
f368c07d AG |
38 | /* |
39 | * Locking model: | |
40 | * | |
41 | * audit_filter_mutex: | |
725131ef SM |
42 | * Synchronizes writes and blocking reads of audit's filterlist |
43 | * data. Rcu is used to traverse the filterlist and access | |
44 | * contents of structs audit_entry, audit_watch and opaque | |
45 | * LSM rules during filtering. If modified, these structures | |
46 | * must be copied and replace their counterparts in the filterlist. | |
47 | * An audit_parent struct is not accessed during filtering, so may | |
48 | * be written directly provided audit_filter_mutex is held. | |
f368c07d AG |
49 | */ |
50 | ||
f368c07d | 51 | /* Audit filter lists, defined in <linux/audit.h> */ |
fe7752ba DW |
52 | struct list_head audit_filter_list[AUDIT_NR_FILTERS] = { |
53 | LIST_HEAD_INIT(audit_filter_list[0]), | |
54 | LIST_HEAD_INIT(audit_filter_list[1]), | |
55 | LIST_HEAD_INIT(audit_filter_list[2]), | |
56 | LIST_HEAD_INIT(audit_filter_list[3]), | |
57 | LIST_HEAD_INIT(audit_filter_list[4]), | |
58 | LIST_HEAD_INIT(audit_filter_list[5]), | |
42d5e376 RGB |
59 | LIST_HEAD_INIT(audit_filter_list[6]), |
60 | #if AUDIT_NR_FILTERS != 7 | |
fe7752ba DW |
61 | #error Fix audit_filter_list initialiser |
62 | #endif | |
63 | }; | |
e45aa212 AV |
64 | static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = { |
65 | LIST_HEAD_INIT(audit_rules_list[0]), | |
66 | LIST_HEAD_INIT(audit_rules_list[1]), | |
67 | LIST_HEAD_INIT(audit_rules_list[2]), | |
68 | LIST_HEAD_INIT(audit_rules_list[3]), | |
69 | LIST_HEAD_INIT(audit_rules_list[4]), | |
70 | LIST_HEAD_INIT(audit_rules_list[5]), | |
42d5e376 | 71 | LIST_HEAD_INIT(audit_rules_list[6]), |
e45aa212 | 72 | }; |
fe7752ba | 73 | |
74c3cbe3 | 74 | DEFINE_MUTEX(audit_filter_mutex); |
f368c07d | 75 | |
219ca394 RGB |
76 | static void audit_free_lsm_field(struct audit_field *f) |
77 | { | |
78 | switch (f->type) { | |
79 | case AUDIT_SUBJ_USER: | |
80 | case AUDIT_SUBJ_ROLE: | |
81 | case AUDIT_SUBJ_TYPE: | |
82 | case AUDIT_SUBJ_SEN: | |
83 | case AUDIT_SUBJ_CLR: | |
84 | case AUDIT_OBJ_USER: | |
85 | case AUDIT_OBJ_ROLE: | |
86 | case AUDIT_OBJ_TYPE: | |
87 | case AUDIT_OBJ_LEV_LOW: | |
88 | case AUDIT_OBJ_LEV_HIGH: | |
89 | kfree(f->lsm_str); | |
90 | security_audit_rule_free(f->lsm_rule); | |
91 | } | |
92 | } | |
93 | ||
93315ed6 | 94 | static inline void audit_free_rule(struct audit_entry *e) |
fe7752ba | 95 | { |
3dc7e315 | 96 | int i; |
c28bb7da | 97 | struct audit_krule *erule = &e->rule; |
ae7b8f41 | 98 | |
f368c07d | 99 | /* some rules don't have associated watches */ |
c28bb7da ZX |
100 | if (erule->watch) |
101 | audit_put_watch(erule->watch); | |
102 | if (erule->fields) | |
219ca394 RGB |
103 | for (i = 0; i < erule->field_count; i++) |
104 | audit_free_lsm_field(&erule->fields[i]); | |
c28bb7da ZX |
105 | kfree(erule->fields); |
106 | kfree(erule->filterkey); | |
93315ed6 AG |
107 | kfree(e); |
108 | } | |
109 | ||
74c3cbe3 | 110 | void audit_free_rule_rcu(struct rcu_head *head) |
93315ed6 AG |
111 | { |
112 | struct audit_entry *e = container_of(head, struct audit_entry, rcu); | |
113 | audit_free_rule(e); | |
114 | } | |
115 | ||
3dc7e315 DG |
116 | /* Initialize an audit filterlist entry. */ |
117 | static inline struct audit_entry *audit_init_entry(u32 field_count) | |
118 | { | |
119 | struct audit_entry *entry; | |
120 | struct audit_field *fields; | |
121 | ||
122 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
123 | if (unlikely(!entry)) | |
124 | return NULL; | |
125 | ||
bab5e2d6 | 126 | fields = kcalloc(field_count, sizeof(*fields), GFP_KERNEL); |
3dc7e315 DG |
127 | if (unlikely(!fields)) { |
128 | kfree(entry); | |
129 | return NULL; | |
130 | } | |
131 | entry->rule.fields = fields; | |
132 | ||
133 | return entry; | |
134 | } | |
135 | ||
93315ed6 AG |
136 | /* Unpack a filter field's string representation from user-space |
137 | * buffer. */ | |
74c3cbe3 | 138 | char *audit_unpack_string(void **bufp, size_t *remain, size_t len) |
93315ed6 AG |
139 | { |
140 | char *str; | |
141 | ||
142 | if (!*bufp || (len == 0) || (len > *remain)) | |
143 | return ERR_PTR(-EINVAL); | |
144 | ||
145 | /* Of the currently implemented string fields, PATH_MAX | |
146 | * defines the longest valid length. | |
147 | */ | |
148 | if (len > PATH_MAX) | |
149 | return ERR_PTR(-ENAMETOOLONG); | |
150 | ||
151 | str = kmalloc(len + 1, GFP_KERNEL); | |
152 | if (unlikely(!str)) | |
153 | return ERR_PTR(-ENOMEM); | |
154 | ||
155 | memcpy(str, *bufp, len); | |
156 | str[len] = 0; | |
157 | *bufp += len; | |
158 | *remain -= len; | |
159 | ||
160 | return str; | |
161 | } | |
162 | ||
fd97646b | 163 | /* Translate an inode field to kernel representation. */ |
f368c07d AG |
164 | static inline int audit_to_inode(struct audit_krule *krule, |
165 | struct audit_field *f) | |
166 | { | |
167 | if (krule->listnr != AUDIT_FILTER_EXIT || | |
3639f170 | 168 | krule->inode_f || krule->watch || krule->tree || |
5af75d8d | 169 | (f->op != Audit_equal && f->op != Audit_not_equal)) |
f368c07d AG |
170 | return -EINVAL; |
171 | ||
172 | krule->inode_f = f; | |
173 | return 0; | |
174 | } | |
175 | ||
b915543b AV |
176 | static __u32 *classes[AUDIT_SYSCALL_CLASSES]; |
177 | ||
178 | int __init audit_register_class(int class, unsigned *list) | |
179 | { | |
bab5e2d6 | 180 | __u32 *p = kcalloc(AUDIT_BITMASK_SIZE, sizeof(__u32), GFP_KERNEL); |
b915543b AV |
181 | if (!p) |
182 | return -ENOMEM; | |
183 | while (*list != ~0U) { | |
184 | unsigned n = *list++; | |
185 | if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { | |
186 | kfree(p); | |
187 | return -EINVAL; | |
188 | } | |
189 | p[AUDIT_WORD(n)] |= AUDIT_BIT(n); | |
190 | } | |
191 | if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { | |
192 | kfree(p); | |
193 | return -EINVAL; | |
194 | } | |
195 | classes[class] = p; | |
196 | return 0; | |
197 | } | |
198 | ||
55669bfa AV |
199 | int audit_match_class(int class, unsigned syscall) |
200 | { | |
c926e4f4 | 201 | if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32)) |
55669bfa AV |
202 | return 0; |
203 | if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) | |
204 | return 0; | |
205 | return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); | |
206 | } | |
207 | ||
327b9eeb | 208 | #ifdef CONFIG_AUDITSYSCALL |
e54dc243 AG |
209 | static inline int audit_match_class_bits(int class, u32 *mask) |
210 | { | |
211 | int i; | |
212 | ||
213 | if (classes[class]) { | |
214 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
215 | if (mask[i] & classes[class][i]) | |
216 | return 0; | |
217 | } | |
218 | return 1; | |
219 | } | |
220 | ||
221 | static int audit_match_signal(struct audit_entry *entry) | |
222 | { | |
223 | struct audit_field *arch = entry->rule.arch_f; | |
224 | ||
225 | if (!arch) { | |
226 | /* When arch is unspecified, we must check both masks on biarch | |
227 | * as syscall number alone is ambiguous. */ | |
228 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
229 | entry->rule.mask) && | |
230 | audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
231 | entry->rule.mask)); | |
232 | } | |
233 | ||
234 | switch(audit_classify_arch(arch->val)) { | |
235 | case 0: /* native */ | |
236 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
237 | entry->rule.mask)); | |
238 | case 1: /* 32bit on biarch */ | |
239 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
240 | entry->rule.mask)); | |
241 | default: | |
242 | return 1; | |
243 | } | |
244 | } | |
327b9eeb | 245 | #endif |
e54dc243 | 246 | |
93315ed6 | 247 | /* Common user-space to kernel rule translation. */ |
56c4911a | 248 | static inline struct audit_entry *audit_to_entry_common(struct audit_rule_data *rule) |
93315ed6 AG |
249 | { |
250 | unsigned listnr; | |
251 | struct audit_entry *entry; | |
93315ed6 AG |
252 | int i, err; |
253 | ||
254 | err = -EINVAL; | |
255 | listnr = rule->flags & ~AUDIT_FILTER_PREPEND; | |
256 | switch(listnr) { | |
257 | default: | |
258 | goto exit_err; | |
93315ed6 AG |
259 | #ifdef CONFIG_AUDITSYSCALL |
260 | case AUDIT_FILTER_ENTRY: | |
5260ecc2 RGB |
261 | pr_err("AUDIT_FILTER_ENTRY is deprecated\n"); |
262 | goto exit_err; | |
93315ed6 AG |
263 | case AUDIT_FILTER_EXIT: |
264 | case AUDIT_FILTER_TASK: | |
265 | #endif | |
7ff68e53 | 266 | case AUDIT_FILTER_USER: |
d904ac03 | 267 | case AUDIT_FILTER_EXCLUDE: |
42d5e376 | 268 | case AUDIT_FILTER_FS: |
93315ed6 AG |
269 | ; |
270 | } | |
014149cc | 271 | if (unlikely(rule->action == AUDIT_POSSIBLE)) { |
f952d10f | 272 | pr_err("AUDIT_POSSIBLE is deprecated\n"); |
014149cc AV |
273 | goto exit_err; |
274 | } | |
275 | if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS) | |
93315ed6 AG |
276 | goto exit_err; |
277 | if (rule->field_count > AUDIT_MAX_FIELDS) | |
278 | goto exit_err; | |
279 | ||
280 | err = -ENOMEM; | |
3dc7e315 DG |
281 | entry = audit_init_entry(rule->field_count); |
282 | if (!entry) | |
93315ed6 | 283 | goto exit_err; |
93315ed6 AG |
284 | |
285 | entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND; | |
286 | entry->rule.listnr = listnr; | |
287 | entry->rule.action = rule->action; | |
288 | entry->rule.field_count = rule->field_count; | |
93315ed6 AG |
289 | |
290 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
291 | entry->rule.mask[i] = rule->mask[i]; | |
292 | ||
b915543b AV |
293 | for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { |
294 | int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; | |
295 | __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; | |
296 | __u32 *class; | |
297 | ||
298 | if (!(*p & AUDIT_BIT(bit))) | |
299 | continue; | |
300 | *p &= ~AUDIT_BIT(bit); | |
301 | class = classes[i]; | |
302 | if (class) { | |
303 | int j; | |
304 | for (j = 0; j < AUDIT_BITMASK_SIZE; j++) | |
305 | entry->rule.mask[j] |= class[j]; | |
306 | } | |
307 | } | |
308 | ||
93315ed6 AG |
309 | return entry; |
310 | ||
311 | exit_err: | |
312 | return ERR_PTR(err); | |
313 | } | |
314 | ||
5af75d8d AV |
315 | static u32 audit_ops[] = |
316 | { | |
317 | [Audit_equal] = AUDIT_EQUAL, | |
318 | [Audit_not_equal] = AUDIT_NOT_EQUAL, | |
319 | [Audit_bitmask] = AUDIT_BIT_MASK, | |
320 | [Audit_bittest] = AUDIT_BIT_TEST, | |
321 | [Audit_lt] = AUDIT_LESS_THAN, | |
322 | [Audit_gt] = AUDIT_GREATER_THAN, | |
323 | [Audit_le] = AUDIT_LESS_THAN_OR_EQUAL, | |
324 | [Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL, | |
325 | }; | |
326 | ||
327 | static u32 audit_to_op(u32 op) | |
328 | { | |
329 | u32 n; | |
330 | for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++) | |
331 | ; | |
332 | return n; | |
333 | } | |
334 | ||
ab61d38e | 335 | /* check if an audit field is valid */ |
62062cf8 | 336 | static int audit_field_valid(struct audit_entry *entry, struct audit_field *f) |
93315ed6 | 337 | { |
62062cf8 EP |
338 | switch(f->type) { |
339 | case AUDIT_MSGTYPE: | |
d904ac03 | 340 | if (entry->rule.listnr != AUDIT_FILTER_EXCLUDE && |
62062cf8 EP |
341 | entry->rule.listnr != AUDIT_FILTER_USER) |
342 | return -EINVAL; | |
343 | break; | |
42d5e376 RGB |
344 | case AUDIT_FSTYPE: |
345 | if (entry->rule.listnr != AUDIT_FILTER_FS) | |
346 | return -EINVAL; | |
347 | break; | |
348 | } | |
349 | ||
350 | switch(entry->rule.listnr) { | |
351 | case AUDIT_FILTER_FS: | |
352 | switch(f->type) { | |
353 | case AUDIT_FSTYPE: | |
354 | case AUDIT_FILTERKEY: | |
355 | break; | |
356 | default: | |
357 | return -EINVAL; | |
358 | } | |
b7a84dea | 359 | } |
93315ed6 | 360 | |
ab61d38e EP |
361 | switch(f->type) { |
362 | default: | |
363 | return -EINVAL; | |
364 | case AUDIT_UID: | |
365 | case AUDIT_EUID: | |
366 | case AUDIT_SUID: | |
367 | case AUDIT_FSUID: | |
368 | case AUDIT_LOGINUID: | |
369 | case AUDIT_OBJ_UID: | |
370 | case AUDIT_GID: | |
371 | case AUDIT_EGID: | |
372 | case AUDIT_SGID: | |
373 | case AUDIT_FSGID: | |
374 | case AUDIT_OBJ_GID: | |
375 | case AUDIT_PID: | |
376 | case AUDIT_PERS: | |
377 | case AUDIT_MSGTYPE: | |
378 | case AUDIT_PPID: | |
379 | case AUDIT_DEVMAJOR: | |
380 | case AUDIT_DEVMINOR: | |
381 | case AUDIT_EXIT: | |
382 | case AUDIT_SUCCESS: | |
78122037 | 383 | case AUDIT_INODE: |
8fae4770 | 384 | case AUDIT_SESSIONID: |
ab61d38e EP |
385 | /* bit ops are only useful on syscall args */ |
386 | if (f->op == Audit_bitmask || f->op == Audit_bittest) | |
387 | return -EINVAL; | |
388 | break; | |
389 | case AUDIT_ARG0: | |
390 | case AUDIT_ARG1: | |
391 | case AUDIT_ARG2: | |
392 | case AUDIT_ARG3: | |
393 | case AUDIT_SUBJ_USER: | |
394 | case AUDIT_SUBJ_ROLE: | |
395 | case AUDIT_SUBJ_TYPE: | |
396 | case AUDIT_SUBJ_SEN: | |
397 | case AUDIT_SUBJ_CLR: | |
398 | case AUDIT_OBJ_USER: | |
399 | case AUDIT_OBJ_ROLE: | |
400 | case AUDIT_OBJ_TYPE: | |
401 | case AUDIT_OBJ_LEV_LOW: | |
402 | case AUDIT_OBJ_LEV_HIGH: | |
403 | case AUDIT_WATCH: | |
404 | case AUDIT_DIR: | |
405 | case AUDIT_FILTERKEY: | |
406 | break; | |
780a7654 EB |
407 | case AUDIT_LOGINUID_SET: |
408 | if ((f->val != 0) && (f->val != 1)) | |
409 | return -EINVAL; | |
410 | /* FALL THROUGH */ | |
ab61d38e | 411 | case AUDIT_ARCH: |
42d5e376 | 412 | case AUDIT_FSTYPE: |
ab61d38e EP |
413 | if (f->op != Audit_not_equal && f->op != Audit_equal) |
414 | return -EINVAL; | |
415 | break; | |
416 | case AUDIT_PERM: | |
417 | if (f->val & ~15) | |
418 | return -EINVAL; | |
419 | break; | |
420 | case AUDIT_FILETYPE: | |
421 | if (f->val & ~S_IFMT) | |
422 | return -EINVAL; | |
423 | break; | |
424 | case AUDIT_FIELD_COMPARE: | |
425 | if (f->val > AUDIT_MAX_FIELD_COMPARE) | |
426 | return -EINVAL; | |
427 | break; | |
34d99af5 | 428 | case AUDIT_EXE: |
23bcc480 | 429 | if (f->op != Audit_not_equal && f->op != Audit_equal) |
34d99af5 | 430 | return -EINVAL; |
34d99af5 | 431 | break; |
b7a84dea | 432 | } |
62062cf8 | 433 | return 0; |
fe7752ba DW |
434 | } |
435 | ||
fd97646b | 436 | /* Translate struct audit_rule_data to kernel's rule representation. */ |
93315ed6 AG |
437 | static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, |
438 | size_t datasz) | |
fe7752ba | 439 | { |
93315ed6 AG |
440 | int err = 0; |
441 | struct audit_entry *entry; | |
442 | void *bufp; | |
3dc7e315 | 443 | size_t remain = datasz - sizeof(struct audit_rule_data); |
fe7752ba | 444 | int i; |
3dc7e315 | 445 | char *str; |
34d99af5 | 446 | struct audit_fsnotify_mark *audit_mark; |
fe7752ba | 447 | |
56c4911a | 448 | entry = audit_to_entry_common(data); |
93315ed6 AG |
449 | if (IS_ERR(entry)) |
450 | goto exit_nofree; | |
fe7752ba | 451 | |
93315ed6 | 452 | bufp = data->buf; |
93315ed6 AG |
453 | for (i = 0; i < data->field_count; i++) { |
454 | struct audit_field *f = &entry->rule.fields[i]; | |
455 | ||
456 | err = -EINVAL; | |
5af75d8d AV |
457 | |
458 | f->op = audit_to_op(data->fieldflags[i]); | |
459 | if (f->op == Audit_bad) | |
93315ed6 AG |
460 | goto exit_free; |
461 | ||
93315ed6 | 462 | f->type = data->fields[i]; |
3dc7e315 | 463 | f->val = data->values[i]; |
62062cf8 | 464 | |
780a7654 | 465 | /* Support legacy tests for a valid loginuid */ |
42f74461 | 466 | if ((f->type == AUDIT_LOGINUID) && (f->val == AUDIT_UID_UNSET)) { |
780a7654 EB |
467 | f->type = AUDIT_LOGINUID_SET; |
468 | f->val = 0; | |
041d7b98 | 469 | entry->rule.pflags |= AUDIT_LOGINUID_LEGACY; |
f1dc4867 RGB |
470 | } |
471 | ||
62062cf8 EP |
472 | err = audit_field_valid(entry, f); |
473 | if (err) | |
474 | goto exit_free; | |
475 | ||
476 | err = -EINVAL; | |
ab61d38e | 477 | switch (f->type) { |
780a7654 | 478 | case AUDIT_LOGINUID: |
0a73dccc AV |
479 | case AUDIT_UID: |
480 | case AUDIT_EUID: | |
481 | case AUDIT_SUID: | |
482 | case AUDIT_FSUID: | |
ca57ec0f | 483 | case AUDIT_OBJ_UID: |
ca57ec0f EB |
484 | f->uid = make_kuid(current_user_ns(), f->val); |
485 | if (!uid_valid(f->uid)) | |
486 | goto exit_free; | |
487 | break; | |
0a73dccc AV |
488 | case AUDIT_GID: |
489 | case AUDIT_EGID: | |
490 | case AUDIT_SGID: | |
491 | case AUDIT_FSGID: | |
ca57ec0f | 492 | case AUDIT_OBJ_GID: |
ca57ec0f EB |
493 | f->gid = make_kgid(current_user_ns(), f->val); |
494 | if (!gid_valid(f->gid)) | |
495 | goto exit_free; | |
496 | break; | |
e54dc243 AG |
497 | case AUDIT_ARCH: |
498 | entry->rule.arch_f = f; | |
499 | break; | |
3a6b9f85 DG |
500 | case AUDIT_SUBJ_USER: |
501 | case AUDIT_SUBJ_ROLE: | |
502 | case AUDIT_SUBJ_TYPE: | |
503 | case AUDIT_SUBJ_SEN: | |
504 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
505 | case AUDIT_OBJ_USER: |
506 | case AUDIT_OBJ_ROLE: | |
507 | case AUDIT_OBJ_TYPE: | |
508 | case AUDIT_OBJ_LEV_LOW: | |
509 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
510 | str = audit_unpack_string(&bufp, &remain, f->val); |
511 | if (IS_ERR(str)) | |
512 | goto exit_free; | |
513 | entry->rule.buflen += f->val; | |
514 | ||
d7a96f3a | 515 | err = security_audit_rule_init(f->type, f->op, str, |
04305e4a | 516 | (void **)&f->lsm_rule); |
3dc7e315 DG |
517 | /* Keep currently invalid fields around in case they |
518 | * become valid after a policy reload. */ | |
519 | if (err == -EINVAL) { | |
f952d10f RGB |
520 | pr_warn("audit rule for LSM \'%s\' is invalid\n", |
521 | str); | |
3dc7e315 DG |
522 | err = 0; |
523 | } | |
524 | if (err) { | |
525 | kfree(str); | |
526 | goto exit_free; | |
527 | } else | |
04305e4a | 528 | f->lsm_str = str; |
3dc7e315 | 529 | break; |
f368c07d AG |
530 | case AUDIT_WATCH: |
531 | str = audit_unpack_string(&bufp, &remain, f->val); | |
532 | if (IS_ERR(str)) | |
533 | goto exit_free; | |
534 | entry->rule.buflen += f->val; | |
535 | ||
536 | err = audit_to_watch(&entry->rule, str, f->val, f->op); | |
537 | if (err) { | |
538 | kfree(str); | |
539 | goto exit_free; | |
540 | } | |
541 | break; | |
74c3cbe3 AV |
542 | case AUDIT_DIR: |
543 | str = audit_unpack_string(&bufp, &remain, f->val); | |
544 | if (IS_ERR(str)) | |
545 | goto exit_free; | |
546 | entry->rule.buflen += f->val; | |
547 | ||
548 | err = audit_make_tree(&entry->rule, str, f->op); | |
549 | kfree(str); | |
550 | if (err) | |
551 | goto exit_free; | |
552 | break; | |
f368c07d AG |
553 | case AUDIT_INODE: |
554 | err = audit_to_inode(&entry->rule, f); | |
555 | if (err) | |
556 | goto exit_free; | |
557 | break; | |
5adc8a6a | 558 | case AUDIT_FILTERKEY: |
5adc8a6a AG |
559 | if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN) |
560 | goto exit_free; | |
561 | str = audit_unpack_string(&bufp, &remain, f->val); | |
562 | if (IS_ERR(str)) | |
563 | goto exit_free; | |
564 | entry->rule.buflen += f->val; | |
565 | entry->rule.filterkey = str; | |
566 | break; | |
34d99af5 RGB |
567 | case AUDIT_EXE: |
568 | if (entry->rule.exe || f->val > PATH_MAX) | |
569 | goto exit_free; | |
570 | str = audit_unpack_string(&bufp, &remain, f->val); | |
571 | if (IS_ERR(str)) { | |
572 | err = PTR_ERR(str); | |
573 | goto exit_free; | |
574 | } | |
575 | entry->rule.buflen += f->val; | |
576 | ||
577 | audit_mark = audit_alloc_mark(&entry->rule, str, f->val); | |
578 | if (IS_ERR(audit_mark)) { | |
579 | kfree(str); | |
580 | err = PTR_ERR(audit_mark); | |
581 | goto exit_free; | |
582 | } | |
583 | entry->rule.exe = audit_mark; | |
584 | break; | |
f368c07d AG |
585 | } |
586 | } | |
587 | ||
5af75d8d AV |
588 | if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal) |
589 | entry->rule.inode_f = NULL; | |
93315ed6 AG |
590 | |
591 | exit_nofree: | |
592 | return entry; | |
593 | ||
594 | exit_free: | |
373e0f34 CG |
595 | if (entry->rule.tree) |
596 | audit_put_tree(entry->rule.tree); /* that's the temporary one */ | |
34d99af5 RGB |
597 | if (entry->rule.exe) |
598 | audit_remove_mark(entry->rule.exe); /* that's the template one */ | |
93315ed6 AG |
599 | audit_free_rule(entry); |
600 | return ERR_PTR(err); | |
601 | } | |
602 | ||
603 | /* Pack a filter field's string representation into data block. */ | |
74c3cbe3 | 604 | static inline size_t audit_pack_string(void **bufp, const char *str) |
93315ed6 AG |
605 | { |
606 | size_t len = strlen(str); | |
607 | ||
608 | memcpy(*bufp, str, len); | |
609 | *bufp += len; | |
610 | ||
611 | return len; | |
612 | } | |
613 | ||
fd97646b | 614 | /* Translate kernel rule representation to struct audit_rule_data. */ |
93315ed6 AG |
615 | static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) |
616 | { | |
617 | struct audit_rule_data *data; | |
618 | void *bufp; | |
619 | int i; | |
620 | ||
621 | data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); | |
622 | if (unlikely(!data)) | |
0a3b483e | 623 | return NULL; |
93315ed6 AG |
624 | memset(data, 0, sizeof(*data)); |
625 | ||
626 | data->flags = krule->flags | krule->listnr; | |
627 | data->action = krule->action; | |
628 | data->field_count = krule->field_count; | |
629 | bufp = data->buf; | |
630 | for (i = 0; i < data->field_count; i++) { | |
631 | struct audit_field *f = &krule->fields[i]; | |
632 | ||
633 | data->fields[i] = f->type; | |
5af75d8d | 634 | data->fieldflags[i] = audit_ops[f->op]; |
93315ed6 | 635 | switch(f->type) { |
3a6b9f85 DG |
636 | case AUDIT_SUBJ_USER: |
637 | case AUDIT_SUBJ_ROLE: | |
638 | case AUDIT_SUBJ_TYPE: | |
639 | case AUDIT_SUBJ_SEN: | |
640 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
641 | case AUDIT_OBJ_USER: |
642 | case AUDIT_OBJ_ROLE: | |
643 | case AUDIT_OBJ_TYPE: | |
644 | case AUDIT_OBJ_LEV_LOW: | |
645 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 | 646 | data->buflen += data->values[i] = |
04305e4a | 647 | audit_pack_string(&bufp, f->lsm_str); |
3dc7e315 | 648 | break; |
f368c07d AG |
649 | case AUDIT_WATCH: |
650 | data->buflen += data->values[i] = | |
cfcad62c EP |
651 | audit_pack_string(&bufp, |
652 | audit_watch_path(krule->watch)); | |
f368c07d | 653 | break; |
74c3cbe3 AV |
654 | case AUDIT_DIR: |
655 | data->buflen += data->values[i] = | |
656 | audit_pack_string(&bufp, | |
657 | audit_tree_path(krule->tree)); | |
658 | break; | |
5adc8a6a AG |
659 | case AUDIT_FILTERKEY: |
660 | data->buflen += data->values[i] = | |
661 | audit_pack_string(&bufp, krule->filterkey); | |
662 | break; | |
34d99af5 RGB |
663 | case AUDIT_EXE: |
664 | data->buflen += data->values[i] = | |
665 | audit_pack_string(&bufp, audit_mark_path(krule->exe)); | |
666 | break; | |
041d7b98 RGB |
667 | case AUDIT_LOGINUID_SET: |
668 | if (krule->pflags & AUDIT_LOGINUID_LEGACY && !f->val) { | |
669 | data->fields[i] = AUDIT_LOGINUID; | |
670 | data->values[i] = AUDIT_UID_UNSET; | |
671 | break; | |
672 | } | |
673 | /* fallthrough if set */ | |
93315ed6 AG |
674 | default: |
675 | data->values[i] = f->val; | |
676 | } | |
677 | } | |
678 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i]; | |
679 | ||
680 | return data; | |
681 | } | |
682 | ||
683 | /* Compare two rules in kernel format. Considered success if rules | |
684 | * don't match. */ | |
685 | static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) | |
686 | { | |
687 | int i; | |
688 | ||
689 | if (a->flags != b->flags || | |
041d7b98 | 690 | a->pflags != b->pflags || |
93315ed6 AG |
691 | a->listnr != b->listnr || |
692 | a->action != b->action || | |
693 | a->field_count != b->field_count) | |
fe7752ba DW |
694 | return 1; |
695 | ||
696 | for (i = 0; i < a->field_count; i++) { | |
93315ed6 AG |
697 | if (a->fields[i].type != b->fields[i].type || |
698 | a->fields[i].op != b->fields[i].op) | |
fe7752ba | 699 | return 1; |
93315ed6 AG |
700 | |
701 | switch(a->fields[i].type) { | |
3a6b9f85 DG |
702 | case AUDIT_SUBJ_USER: |
703 | case AUDIT_SUBJ_ROLE: | |
704 | case AUDIT_SUBJ_TYPE: | |
705 | case AUDIT_SUBJ_SEN: | |
706 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
707 | case AUDIT_OBJ_USER: |
708 | case AUDIT_OBJ_ROLE: | |
709 | case AUDIT_OBJ_TYPE: | |
710 | case AUDIT_OBJ_LEV_LOW: | |
711 | case AUDIT_OBJ_LEV_HIGH: | |
04305e4a | 712 | if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str)) |
3dc7e315 DG |
713 | return 1; |
714 | break; | |
f368c07d | 715 | case AUDIT_WATCH: |
cfcad62c EP |
716 | if (strcmp(audit_watch_path(a->watch), |
717 | audit_watch_path(b->watch))) | |
f368c07d AG |
718 | return 1; |
719 | break; | |
74c3cbe3 AV |
720 | case AUDIT_DIR: |
721 | if (strcmp(audit_tree_path(a->tree), | |
722 | audit_tree_path(b->tree))) | |
723 | return 1; | |
724 | break; | |
5adc8a6a AG |
725 | case AUDIT_FILTERKEY: |
726 | /* both filterkeys exist based on above type compare */ | |
727 | if (strcmp(a->filterkey, b->filterkey)) | |
728 | return 1; | |
729 | break; | |
34d99af5 RGB |
730 | case AUDIT_EXE: |
731 | /* both paths exist based on above type compare */ | |
732 | if (strcmp(audit_mark_path(a->exe), | |
733 | audit_mark_path(b->exe))) | |
734 | return 1; | |
735 | break; | |
ca57ec0f EB |
736 | case AUDIT_UID: |
737 | case AUDIT_EUID: | |
738 | case AUDIT_SUID: | |
739 | case AUDIT_FSUID: | |
740 | case AUDIT_LOGINUID: | |
741 | case AUDIT_OBJ_UID: | |
742 | if (!uid_eq(a->fields[i].uid, b->fields[i].uid)) | |
743 | return 1; | |
744 | break; | |
745 | case AUDIT_GID: | |
746 | case AUDIT_EGID: | |
747 | case AUDIT_SGID: | |
748 | case AUDIT_FSGID: | |
749 | case AUDIT_OBJ_GID: | |
750 | if (!gid_eq(a->fields[i].gid, b->fields[i].gid)) | |
751 | return 1; | |
752 | break; | |
93315ed6 AG |
753 | default: |
754 | if (a->fields[i].val != b->fields[i].val) | |
755 | return 1; | |
756 | } | |
fe7752ba DW |
757 | } |
758 | ||
759 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
760 | if (a->mask[i] != b->mask[i]) | |
761 | return 1; | |
762 | ||
763 | return 0; | |
764 | } | |
765 | ||
04305e4a | 766 | /* Duplicate LSM field information. The lsm_rule is opaque, so must be |
3dc7e315 | 767 | * re-initialized. */ |
d7a96f3a | 768 | static inline int audit_dupe_lsm_field(struct audit_field *df, |
3dc7e315 DG |
769 | struct audit_field *sf) |
770 | { | |
771 | int ret = 0; | |
04305e4a | 772 | char *lsm_str; |
3dc7e315 | 773 | |
04305e4a AD |
774 | /* our own copy of lsm_str */ |
775 | lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL); | |
776 | if (unlikely(!lsm_str)) | |
3e1fbd12 | 777 | return -ENOMEM; |
04305e4a | 778 | df->lsm_str = lsm_str; |
3dc7e315 | 779 | |
04305e4a AD |
780 | /* our own (refreshed) copy of lsm_rule */ |
781 | ret = security_audit_rule_init(df->type, df->op, df->lsm_str, | |
782 | (void **)&df->lsm_rule); | |
3dc7e315 DG |
783 | /* Keep currently invalid fields around in case they |
784 | * become valid after a policy reload. */ | |
785 | if (ret == -EINVAL) { | |
f952d10f RGB |
786 | pr_warn("audit rule for LSM \'%s\' is invalid\n", |
787 | df->lsm_str); | |
3dc7e315 DG |
788 | ret = 0; |
789 | } | |
790 | ||
791 | return ret; | |
792 | } | |
793 | ||
794 | /* Duplicate an audit rule. This will be a deep copy with the exception | |
d7a96f3a | 795 | * of the watch - that pointer is carried over. The LSM specific fields |
3dc7e315 | 796 | * will be updated in the copy. The point is to be able to replace the old |
f368c07d AG |
797 | * rule with the new rule in the filterlist, then free the old rule. |
798 | * The rlist element is undefined; list manipulations are handled apart from | |
799 | * the initial copy. */ | |
ae7b8f41 | 800 | struct audit_entry *audit_dupe_rule(struct audit_krule *old) |
3dc7e315 DG |
801 | { |
802 | u32 fcount = old->field_count; | |
803 | struct audit_entry *entry; | |
804 | struct audit_krule *new; | |
5adc8a6a | 805 | char *fk; |
3dc7e315 DG |
806 | int i, err = 0; |
807 | ||
808 | entry = audit_init_entry(fcount); | |
809 | if (unlikely(!entry)) | |
810 | return ERR_PTR(-ENOMEM); | |
811 | ||
812 | new = &entry->rule; | |
3dc7e315 | 813 | new->flags = old->flags; |
041d7b98 | 814 | new->pflags = old->pflags; |
3dc7e315 DG |
815 | new->listnr = old->listnr; |
816 | new->action = old->action; | |
817 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
818 | new->mask[i] = old->mask[i]; | |
0590b933 | 819 | new->prio = old->prio; |
3dc7e315 | 820 | new->buflen = old->buflen; |
f368c07d | 821 | new->inode_f = old->inode_f; |
3dc7e315 | 822 | new->field_count = old->field_count; |
ae7b8f41 | 823 | |
74c3cbe3 AV |
824 | /* |
825 | * note that we are OK with not refcounting here; audit_match_tree() | |
826 | * never dereferences tree and we can't get false positives there | |
827 | * since we'd have to have rule gone from the list *and* removed | |
828 | * before the chunks found by lookup had been allocated, i.e. before | |
829 | * the beginning of list scan. | |
830 | */ | |
831 | new->tree = old->tree; | |
3dc7e315 DG |
832 | memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount); |
833 | ||
04305e4a | 834 | /* deep copy this information, updating the lsm_rule fields, because |
3dc7e315 DG |
835 | * the originals will all be freed when the old rule is freed. */ |
836 | for (i = 0; i < fcount; i++) { | |
837 | switch (new->fields[i].type) { | |
3a6b9f85 DG |
838 | case AUDIT_SUBJ_USER: |
839 | case AUDIT_SUBJ_ROLE: | |
840 | case AUDIT_SUBJ_TYPE: | |
841 | case AUDIT_SUBJ_SEN: | |
842 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
843 | case AUDIT_OBJ_USER: |
844 | case AUDIT_OBJ_ROLE: | |
845 | case AUDIT_OBJ_TYPE: | |
846 | case AUDIT_OBJ_LEV_LOW: | |
847 | case AUDIT_OBJ_LEV_HIGH: | |
d7a96f3a | 848 | err = audit_dupe_lsm_field(&new->fields[i], |
3dc7e315 | 849 | &old->fields[i]); |
5adc8a6a AG |
850 | break; |
851 | case AUDIT_FILTERKEY: | |
852 | fk = kstrdup(old->filterkey, GFP_KERNEL); | |
853 | if (unlikely(!fk)) | |
854 | err = -ENOMEM; | |
855 | else | |
856 | new->filterkey = fk; | |
34d99af5 RGB |
857 | break; |
858 | case AUDIT_EXE: | |
859 | err = audit_dupe_exe(new, old); | |
860 | break; | |
3dc7e315 DG |
861 | } |
862 | if (err) { | |
34d99af5 RGB |
863 | if (new->exe) |
864 | audit_remove_mark(new->exe); | |
3dc7e315 DG |
865 | audit_free_rule(entry); |
866 | return ERR_PTR(err); | |
867 | } | |
868 | } | |
869 | ||
ae7b8f41 EP |
870 | if (old->watch) { |
871 | audit_get_watch(old->watch); | |
872 | new->watch = old->watch; | |
f368c07d AG |
873 | } |
874 | ||
3dc7e315 DG |
875 | return entry; |
876 | } | |
877 | ||
f368c07d AG |
878 | /* Find an existing audit rule. |
879 | * Caller must hold audit_filter_mutex to prevent stale rule data. */ | |
880 | static struct audit_entry *audit_find_rule(struct audit_entry *entry, | |
36c4f1b1 | 881 | struct list_head **p) |
f368c07d AG |
882 | { |
883 | struct audit_entry *e, *found = NULL; | |
36c4f1b1 | 884 | struct list_head *list; |
f368c07d AG |
885 | int h; |
886 | ||
36c4f1b1 AV |
887 | if (entry->rule.inode_f) { |
888 | h = audit_hash_ino(entry->rule.inode_f->val); | |
889 | *p = list = &audit_inode_hash[h]; | |
890 | } else if (entry->rule.watch) { | |
f368c07d AG |
891 | /* we don't know the inode number, so must walk entire hash */ |
892 | for (h = 0; h < AUDIT_INODE_BUCKETS; h++) { | |
893 | list = &audit_inode_hash[h]; | |
894 | list_for_each_entry(e, list, list) | |
895 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
896 | found = e; | |
897 | goto out; | |
898 | } | |
899 | } | |
900 | goto out; | |
36c4f1b1 AV |
901 | } else { |
902 | *p = list = &audit_filter_list[entry->rule.listnr]; | |
f368c07d AG |
903 | } |
904 | ||
905 | list_for_each_entry(e, list, list) | |
906 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
907 | found = e; | |
908 | goto out; | |
909 | } | |
910 | ||
911 | out: | |
912 | return found; | |
913 | } | |
914 | ||
0590b933 AV |
915 | static u64 prio_low = ~0ULL/2; |
916 | static u64 prio_high = ~0ULL/2 - 1; | |
917 | ||
f368c07d | 918 | /* Add rule to given filterlist if not a duplicate. */ |
36c4f1b1 | 919 | static inline int audit_add_rule(struct audit_entry *entry) |
fe7752ba | 920 | { |
93315ed6 | 921 | struct audit_entry *e; |
f368c07d | 922 | struct audit_watch *watch = entry->rule.watch; |
74c3cbe3 | 923 | struct audit_tree *tree = entry->rule.tree; |
36c4f1b1 | 924 | struct list_head *list; |
ae9d2fb4 | 925 | int err = 0; |
471a5c7c AV |
926 | #ifdef CONFIG_AUDITSYSCALL |
927 | int dont_count = 0; | |
928 | ||
42d5e376 RGB |
929 | /* If any of these, don't count towards total */ |
930 | switch(entry->rule.listnr) { | |
931 | case AUDIT_FILTER_USER: | |
d904ac03 | 932 | case AUDIT_FILTER_EXCLUDE: |
42d5e376 | 933 | case AUDIT_FILTER_FS: |
471a5c7c | 934 | dont_count = 1; |
42d5e376 | 935 | } |
471a5c7c | 936 | #endif |
f368c07d | 937 | |
f368c07d | 938 | mutex_lock(&audit_filter_mutex); |
36c4f1b1 | 939 | e = audit_find_rule(entry, &list); |
f368c07d | 940 | if (e) { |
35fe4d0b | 941 | mutex_unlock(&audit_filter_mutex); |
f368c07d | 942 | err = -EEXIST; |
74c3cbe3 AV |
943 | /* normally audit_add_tree_rule() will free it on failure */ |
944 | if (tree) | |
945 | audit_put_tree(tree); | |
f8259b26 | 946 | return err; |
f368c07d | 947 | } |
fe7752ba | 948 | |
f368c07d AG |
949 | if (watch) { |
950 | /* audit_filter_mutex is dropped and re-taken during this call */ | |
ae7b8f41 | 951 | err = audit_add_watch(&entry->rule, &list); |
f368c07d AG |
952 | if (err) { |
953 | mutex_unlock(&audit_filter_mutex); | |
2f992ee8 CG |
954 | /* |
955 | * normally audit_add_tree_rule() will free it | |
956 | * on failure | |
957 | */ | |
958 | if (tree) | |
959 | audit_put_tree(tree); | |
f8259b26 | 960 | return err; |
f368c07d | 961 | } |
fe7752ba | 962 | } |
74c3cbe3 AV |
963 | if (tree) { |
964 | err = audit_add_tree_rule(&entry->rule); | |
965 | if (err) { | |
966 | mutex_unlock(&audit_filter_mutex); | |
f8259b26 | 967 | return err; |
74c3cbe3 AV |
968 | } |
969 | } | |
fe7752ba | 970 | |
0590b933 AV |
971 | entry->rule.prio = ~0ULL; |
972 | if (entry->rule.listnr == AUDIT_FILTER_EXIT) { | |
973 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) | |
974 | entry->rule.prio = ++prio_high; | |
975 | else | |
976 | entry->rule.prio = --prio_low; | |
977 | } | |
978 | ||
fe7752ba | 979 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
e45aa212 AV |
980 | list_add(&entry->rule.list, |
981 | &audit_rules_list[entry->rule.listnr]); | |
fe7752ba | 982 | list_add_rcu(&entry->list, list); |
6a2bceec | 983 | entry->rule.flags &= ~AUDIT_FILTER_PREPEND; |
fe7752ba | 984 | } else { |
e45aa212 AV |
985 | list_add_tail(&entry->rule.list, |
986 | &audit_rules_list[entry->rule.listnr]); | |
fe7752ba DW |
987 | list_add_tail_rcu(&entry->list, list); |
988 | } | |
471a5c7c AV |
989 | #ifdef CONFIG_AUDITSYSCALL |
990 | if (!dont_count) | |
991 | audit_n_rules++; | |
e54dc243 AG |
992 | |
993 | if (!audit_match_signal(entry)) | |
994 | audit_signals++; | |
471a5c7c | 995 | #endif |
f368c07d | 996 | mutex_unlock(&audit_filter_mutex); |
fe7752ba | 997 | |
f368c07d | 998 | return err; |
fe7752ba DW |
999 | } |
1000 | ||
f368c07d | 1001 | /* Remove an existing rule from filterlist. */ |
7f492942 | 1002 | int audit_del_rule(struct audit_entry *entry) |
fe7752ba DW |
1003 | { |
1004 | struct audit_entry *e; | |
74c3cbe3 | 1005 | struct audit_tree *tree = entry->rule.tree; |
36c4f1b1 | 1006 | struct list_head *list; |
36c4f1b1 | 1007 | int ret = 0; |
471a5c7c AV |
1008 | #ifdef CONFIG_AUDITSYSCALL |
1009 | int dont_count = 0; | |
1010 | ||
42d5e376 RGB |
1011 | /* If any of these, don't count towards total */ |
1012 | switch(entry->rule.listnr) { | |
1013 | case AUDIT_FILTER_USER: | |
d904ac03 | 1014 | case AUDIT_FILTER_EXCLUDE: |
42d5e376 | 1015 | case AUDIT_FILTER_FS: |
471a5c7c | 1016 | dont_count = 1; |
42d5e376 | 1017 | } |
471a5c7c | 1018 | #endif |
f368c07d | 1019 | |
f368c07d | 1020 | mutex_lock(&audit_filter_mutex); |
36c4f1b1 | 1021 | e = audit_find_rule(entry, &list); |
f368c07d | 1022 | if (!e) { |
f368c07d AG |
1023 | ret = -ENOENT; |
1024 | goto out; | |
1025 | } | |
1026 | ||
cfcad62c | 1027 | if (e->rule.watch) |
a05fb6cc | 1028 | audit_remove_watch_rule(&e->rule); |
f368c07d | 1029 | |
74c3cbe3 AV |
1030 | if (e->rule.tree) |
1031 | audit_remove_tree_rule(&e->rule); | |
1032 | ||
34d99af5 RGB |
1033 | if (e->rule.exe) |
1034 | audit_remove_mark_rule(&e->rule); | |
1035 | ||
471a5c7c AV |
1036 | #ifdef CONFIG_AUDITSYSCALL |
1037 | if (!dont_count) | |
1038 | audit_n_rules--; | |
e54dc243 AG |
1039 | |
1040 | if (!audit_match_signal(entry)) | |
1041 | audit_signals--; | |
471a5c7c | 1042 | #endif |
8c85fc9a RGB |
1043 | |
1044 | list_del_rcu(&e->list); | |
1045 | list_del(&e->rule.list); | |
1046 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
f368c07d | 1047 | |
f368c07d | 1048 | out: |
8c85fc9a RGB |
1049 | mutex_unlock(&audit_filter_mutex); |
1050 | ||
74c3cbe3 AV |
1051 | if (tree) |
1052 | audit_put_tree(tree); /* that's the temporary one */ | |
f368c07d AG |
1053 | |
1054 | return ret; | |
fe7752ba DW |
1055 | } |
1056 | ||
93315ed6 | 1057 | /* List rules using struct audit_rule_data. */ |
45a0642b | 1058 | static void audit_list_rules(int seq, struct sk_buff_head *q) |
93315ed6 | 1059 | { |
9044e6bc | 1060 | struct sk_buff *skb; |
e45aa212 | 1061 | struct audit_krule *r; |
93315ed6 AG |
1062 | int i; |
1063 | ||
f368c07d AG |
1064 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1065 | * iterator to sync with list writers. */ | |
93315ed6 | 1066 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
e45aa212 | 1067 | list_for_each_entry(r, &audit_rules_list[i], list) { |
f368c07d AG |
1068 | struct audit_rule_data *data; |
1069 | ||
e45aa212 | 1070 | data = audit_krule_to_data(r); |
f368c07d AG |
1071 | if (unlikely(!data)) |
1072 | break; | |
45a0642b PM |
1073 | skb = audit_make_reply(seq, AUDIT_LIST_RULES, 0, 1, |
1074 | data, | |
f9441639 | 1075 | sizeof(*data) + data->buflen); |
9044e6bc AV |
1076 | if (skb) |
1077 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1078 | kfree(data); |
1079 | } | |
1080 | } | |
45a0642b | 1081 | skb = audit_make_reply(seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); |
9044e6bc AV |
1082 | if (skb) |
1083 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1084 | } |
1085 | ||
5adc8a6a | 1086 | /* Log rule additions and removals */ |
dc9eb698 | 1087 | static void audit_log_rule_change(char *action, struct audit_krule *rule, int res) |
5adc8a6a AG |
1088 | { |
1089 | struct audit_buffer *ab; | |
1090 | ||
1a6b9f23 EP |
1091 | if (!audit_enabled) |
1092 | return; | |
1093 | ||
5adc8a6a AG |
1094 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
1095 | if (!ab) | |
1096 | return; | |
5c5b8d8b | 1097 | audit_log_session_info(ab); |
b122c376 | 1098 | audit_log_task_context(ab); |
c1e8f06d | 1099 | audit_log_format(ab, " op=%s", action); |
9d960985 | 1100 | audit_log_key(ab, rule->filterkey); |
5adc8a6a AG |
1101 | audit_log_format(ab, " list=%d res=%d", rule->listnr, res); |
1102 | audit_log_end(ab); | |
1103 | } | |
1104 | ||
fe7752ba | 1105 | /** |
ce0d9f04 | 1106 | * audit_rule_change - apply all rules to the specified message type |
fe7752ba | 1107 | * @type: audit message type |
fe7752ba DW |
1108 | * @seq: netlink audit message sequence (serial) number |
1109 | * @data: payload data | |
93315ed6 | 1110 | * @datasz: size of payload data |
fe7752ba | 1111 | */ |
45a0642b | 1112 | int audit_rule_change(int type, int seq, void *data, size_t datasz) |
fe7752ba | 1113 | { |
93315ed6 AG |
1114 | int err = 0; |
1115 | struct audit_entry *entry; | |
fe7752ba | 1116 | |
e85322d2 RGB |
1117 | entry = audit_data_to_entry(data, datasz); |
1118 | if (IS_ERR(entry)) | |
1119 | return PTR_ERR(entry); | |
1120 | ||
fe7752ba | 1121 | switch (type) { |
93315ed6 | 1122 | case AUDIT_ADD_RULE: |
36c4f1b1 | 1123 | err = audit_add_rule(entry); |
e7df61f4 | 1124 | audit_log_rule_change("add_rule", &entry->rule, !err); |
fe7752ba | 1125 | break; |
93315ed6 | 1126 | case AUDIT_DEL_RULE: |
36c4f1b1 | 1127 | err = audit_del_rule(entry); |
e7df61f4 | 1128 | audit_log_rule_change("remove_rule", &entry->rule, !err); |
fe7752ba DW |
1129 | break; |
1130 | default: | |
739c9503 EP |
1131 | err = -EINVAL; |
1132 | WARN_ON(1); | |
fe7752ba DW |
1133 | } |
1134 | ||
34d99af5 RGB |
1135 | if (err || type == AUDIT_DEL_RULE) { |
1136 | if (entry->rule.exe) | |
1137 | audit_remove_mark(entry->rule.exe); | |
e85322d2 | 1138 | audit_free_rule(entry); |
34d99af5 | 1139 | } |
e85322d2 | 1140 | |
fe7752ba DW |
1141 | return err; |
1142 | } | |
1143 | ||
ce0d9f04 RGB |
1144 | /** |
1145 | * audit_list_rules_send - list the audit rules | |
d211f177 | 1146 | * @request_skb: skb of request we are replying to (used to target the reply) |
ce0d9f04 RGB |
1147 | * @seq: netlink audit message sequence (serial) number |
1148 | */ | |
6f285b19 | 1149 | int audit_list_rules_send(struct sk_buff *request_skb, int seq) |
ce0d9f04 | 1150 | { |
6f285b19 EB |
1151 | u32 portid = NETLINK_CB(request_skb).portid; |
1152 | struct net *net = sock_net(NETLINK_CB(request_skb).sk); | |
ce0d9f04 RGB |
1153 | struct task_struct *tsk; |
1154 | struct audit_netlink_list *dest; | |
1155 | int err = 0; | |
1156 | ||
1157 | /* We can't just spew out the rules here because we might fill | |
1158 | * the available socket buffer space and deadlock waiting for | |
1159 | * auditctl to read from it... which isn't ever going to | |
1160 | * happen if we're actually running in the context of auditctl | |
1161 | * trying to _send_ the stuff */ | |
1162 | ||
1163 | dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); | |
1164 | if (!dest) | |
1165 | return -ENOMEM; | |
6f285b19 | 1166 | dest->net = get_net(net); |
ce0d9f04 | 1167 | dest->portid = portid; |
ce0d9f04 RGB |
1168 | skb_queue_head_init(&dest->q); |
1169 | ||
1170 | mutex_lock(&audit_filter_mutex); | |
45a0642b | 1171 | audit_list_rules(seq, &dest->q); |
ce0d9f04 RGB |
1172 | mutex_unlock(&audit_filter_mutex); |
1173 | ||
1174 | tsk = kthread_run(audit_send_list, dest, "audit_send_list"); | |
1175 | if (IS_ERR(tsk)) { | |
1176 | skb_queue_purge(&dest->q); | |
1177 | kfree(dest); | |
1178 | err = PTR_ERR(tsk); | |
1179 | } | |
1180 | ||
1181 | return err; | |
1182 | } | |
1183 | ||
5af75d8d | 1184 | int audit_comparator(u32 left, u32 op, u32 right) |
fe7752ba DW |
1185 | { |
1186 | switch (op) { | |
5af75d8d | 1187 | case Audit_equal: |
fe7752ba | 1188 | return (left == right); |
5af75d8d | 1189 | case Audit_not_equal: |
fe7752ba | 1190 | return (left != right); |
5af75d8d | 1191 | case Audit_lt: |
fe7752ba | 1192 | return (left < right); |
5af75d8d | 1193 | case Audit_le: |
fe7752ba | 1194 | return (left <= right); |
5af75d8d | 1195 | case Audit_gt: |
fe7752ba | 1196 | return (left > right); |
5af75d8d | 1197 | case Audit_ge: |
fe7752ba | 1198 | return (left >= right); |
5af75d8d | 1199 | case Audit_bitmask: |
74f2345b | 1200 | return (left & right); |
5af75d8d | 1201 | case Audit_bittest: |
74f2345b | 1202 | return ((left & right) == right); |
5af75d8d AV |
1203 | default: |
1204 | BUG(); | |
1205 | return 0; | |
fe7752ba DW |
1206 | } |
1207 | } | |
1208 | ||
ca57ec0f EB |
1209 | int audit_uid_comparator(kuid_t left, u32 op, kuid_t right) |
1210 | { | |
1211 | switch (op) { | |
1212 | case Audit_equal: | |
1213 | return uid_eq(left, right); | |
1214 | case Audit_not_equal: | |
1215 | return !uid_eq(left, right); | |
1216 | case Audit_lt: | |
1217 | return uid_lt(left, right); | |
1218 | case Audit_le: | |
1219 | return uid_lte(left, right); | |
1220 | case Audit_gt: | |
1221 | return uid_gt(left, right); | |
1222 | case Audit_ge: | |
1223 | return uid_gte(left, right); | |
1224 | case Audit_bitmask: | |
1225 | case Audit_bittest: | |
1226 | default: | |
1227 | BUG(); | |
1228 | return 0; | |
1229 | } | |
1230 | } | |
1231 | ||
1232 | int audit_gid_comparator(kgid_t left, u32 op, kgid_t right) | |
1233 | { | |
1234 | switch (op) { | |
1235 | case Audit_equal: | |
1236 | return gid_eq(left, right); | |
1237 | case Audit_not_equal: | |
1238 | return !gid_eq(left, right); | |
1239 | case Audit_lt: | |
1240 | return gid_lt(left, right); | |
1241 | case Audit_le: | |
1242 | return gid_lte(left, right); | |
1243 | case Audit_gt: | |
1244 | return gid_gt(left, right); | |
1245 | case Audit_ge: | |
1246 | return gid_gte(left, right); | |
1247 | case Audit_bitmask: | |
1248 | case Audit_bittest: | |
1249 | default: | |
1250 | BUG(); | |
1251 | return 0; | |
1252 | } | |
1253 | } | |
1254 | ||
bfcec708 JL |
1255 | /** |
1256 | * parent_len - find the length of the parent portion of a pathname | |
1257 | * @path: pathname of which to determine length | |
1258 | */ | |
1259 | int parent_len(const char *path) | |
1260 | { | |
1261 | int plen; | |
1262 | const char *p; | |
1263 | ||
1264 | plen = strlen(path); | |
1265 | ||
1266 | if (plen == 0) | |
1267 | return plen; | |
1268 | ||
1269 | /* disregard trailing slashes */ | |
1270 | p = path + plen - 1; | |
1271 | while ((*p == '/') && (p > path)) | |
1272 | p--; | |
1273 | ||
1274 | /* walk backward until we find the next slash or hit beginning */ | |
1275 | while ((*p != '/') && (p > path)) | |
1276 | p--; | |
1277 | ||
1278 | /* did we find a slash? Then increment to include it in path */ | |
1279 | if (*p == '/') | |
1280 | p++; | |
1281 | ||
1282 | return p - path; | |
1283 | } | |
1284 | ||
e3d6b07b JL |
1285 | /** |
1286 | * audit_compare_dname_path - compare given dentry name with last component in | |
1287 | * given path. Return of 0 indicates a match. | |
1288 | * @dname: dentry name that we're comparing | |
1289 | * @path: full pathname that we're comparing | |
1290 | * @parentlen: length of the parent if known. Passing in AUDIT_NAME_FULL | |
1291 | * here indicates that we must compute this value. | |
1292 | */ | |
1293 | int audit_compare_dname_path(const char *dname, const char *path, int parentlen) | |
f368c07d | 1294 | { |
e3d6b07b | 1295 | int dlen, pathlen; |
f368c07d AG |
1296 | const char *p; |
1297 | ||
f368c07d | 1298 | dlen = strlen(dname); |
29e9a346 EP |
1299 | pathlen = strlen(path); |
1300 | if (pathlen < dlen) | |
f368c07d AG |
1301 | return 1; |
1302 | ||
e3d6b07b | 1303 | parentlen = parentlen == AUDIT_NAME_FULL ? parent_len(path) : parentlen; |
29e9a346 | 1304 | if (pathlen - parentlen != dlen) |
f368c07d | 1305 | return 1; |
29e9a346 EP |
1306 | |
1307 | p = path + parentlen; | |
fe7752ba | 1308 | |
f368c07d AG |
1309 | return strncmp(p, dname, dlen); |
1310 | } | |
fe7752ba | 1311 | |
86b2efbe | 1312 | int audit_filter(int msgtype, unsigned int listtype) |
fe7752ba DW |
1313 | { |
1314 | struct audit_entry *e; | |
86b2efbe | 1315 | int ret = 1; /* Audit by default */ |
9ce34218 | 1316 | |
fe7752ba | 1317 | rcu_read_lock(); |
86b2efbe | 1318 | if (list_empty(&audit_filter_list[listtype])) |
fe7752ba | 1319 | goto unlock_and_return; |
86b2efbe RGB |
1320 | list_for_each_entry_rcu(e, &audit_filter_list[listtype], list) { |
1321 | int i, result = 0; | |
fe7752ba | 1322 | |
93315ed6 AG |
1323 | for (i = 0; i < e->rule.field_count; i++) { |
1324 | struct audit_field *f = &e->rule.fields[i]; | |
86b2efbe RGB |
1325 | pid_t pid; |
1326 | u32 sid; | |
1327 | ||
1328 | switch (f->type) { | |
1329 | case AUDIT_PID: | |
1330 | pid = task_pid_nr(current); | |
1331 | result = audit_comparator(pid, f->op, f->val); | |
1332 | break; | |
1333 | case AUDIT_UID: | |
1334 | result = audit_uid_comparator(current_uid(), f->op, f->uid); | |
1335 | break; | |
1336 | case AUDIT_GID: | |
1337 | result = audit_gid_comparator(current_gid(), f->op, f->gid); | |
1338 | break; | |
1339 | case AUDIT_LOGINUID: | |
1340 | result = audit_uid_comparator(audit_get_loginuid(current), | |
1341 | f->op, f->uid); | |
1342 | break; | |
1343 | case AUDIT_LOGINUID_SET: | |
1344 | result = audit_comparator(audit_loginuid_set(current), | |
1345 | f->op, f->val); | |
1346 | break; | |
1347 | case AUDIT_MSGTYPE: | |
1348 | result = audit_comparator(msgtype, f->op, f->val); | |
1349 | break; | |
1350 | case AUDIT_SUBJ_USER: | |
1351 | case AUDIT_SUBJ_ROLE: | |
1352 | case AUDIT_SUBJ_TYPE: | |
1353 | case AUDIT_SUBJ_SEN: | |
1354 | case AUDIT_SUBJ_CLR: | |
1355 | if (f->lsm_rule) { | |
1356 | security_task_getsecid(current, &sid); | |
1357 | result = security_audit_rule_match(sid, | |
1358 | f->type, f->op, f->lsm_rule, NULL); | |
1359 | } | |
1360 | break; | |
29c1372d OM |
1361 | case AUDIT_EXE: |
1362 | result = audit_exe_compare(current, e->rule.exe); | |
1363 | if (f->op == Audit_not_equal) | |
1364 | result = !result; | |
1365 | break; | |
86b2efbe RGB |
1366 | default: |
1367 | goto unlock_and_return; | |
fe7752ba | 1368 | } |
86b2efbe RGB |
1369 | if (result < 0) /* error */ |
1370 | goto unlock_and_return; | |
1371 | if (!result) | |
1372 | break; | |
1373 | } | |
1374 | if (result > 0) { | |
d904ac03 | 1375 | if (e->rule.action == AUDIT_NEVER || listtype == AUDIT_FILTER_EXCLUDE) |
86b2efbe RGB |
1376 | ret = 0; |
1377 | break; | |
fe7752ba | 1378 | } |
fe7752ba DW |
1379 | } |
1380 | unlock_and_return: | |
1381 | rcu_read_unlock(); | |
86b2efbe | 1382 | return ret; |
fe7752ba | 1383 | } |
3dc7e315 | 1384 | |
e45aa212 | 1385 | static int update_lsm_rule(struct audit_krule *r) |
1a9d0797 | 1386 | { |
e45aa212 | 1387 | struct audit_entry *entry = container_of(r, struct audit_entry, rule); |
1a9d0797 | 1388 | struct audit_entry *nentry; |
1a9d0797 AV |
1389 | int err = 0; |
1390 | ||
e45aa212 | 1391 | if (!security_audit_rule_known(r)) |
1a9d0797 AV |
1392 | return 0; |
1393 | ||
ae7b8f41 | 1394 | nentry = audit_dupe_rule(r); |
34d99af5 RGB |
1395 | if (entry->rule.exe) |
1396 | audit_remove_mark(entry->rule.exe); | |
1a9d0797 AV |
1397 | if (IS_ERR(nentry)) { |
1398 | /* save the first error encountered for the | |
1399 | * return value */ | |
1400 | err = PTR_ERR(nentry); | |
1401 | audit_panic("error updating LSM filters"); | |
ae7b8f41 | 1402 | if (r->watch) |
e45aa212 | 1403 | list_del(&r->rlist); |
1a9d0797 | 1404 | list_del_rcu(&entry->list); |
e45aa212 | 1405 | list_del(&r->list); |
1a9d0797 | 1406 | } else { |
ae7b8f41 | 1407 | if (r->watch || r->tree) |
e45aa212 | 1408 | list_replace_init(&r->rlist, &nentry->rule.rlist); |
1a9d0797 | 1409 | list_replace_rcu(&entry->list, &nentry->list); |
e45aa212 | 1410 | list_replace(&r->list, &nentry->rule.list); |
1a9d0797 AV |
1411 | } |
1412 | call_rcu(&entry->rcu, audit_free_rule_rcu); | |
1413 | ||
1414 | return err; | |
1415 | } | |
1416 | ||
04305e4a | 1417 | /* This function will re-initialize the lsm_rule field of all applicable rules. |
d7a96f3a | 1418 | * It will traverse the filter lists serarching for rules that contain LSM |
3dc7e315 | 1419 | * specific filter fields. When such a rule is found, it is copied, the |
d7a96f3a | 1420 | * LSM field is re-initialized, and the old rule is replaced with the |
3dc7e315 | 1421 | * updated rule. */ |
d7a96f3a | 1422 | int audit_update_lsm_rules(void) |
3dc7e315 | 1423 | { |
e45aa212 | 1424 | struct audit_krule *r, *n; |
3dc7e315 DG |
1425 | int i, err = 0; |
1426 | ||
f368c07d AG |
1427 | /* audit_filter_mutex synchronizes the writers */ |
1428 | mutex_lock(&audit_filter_mutex); | |
3dc7e315 DG |
1429 | |
1430 | for (i = 0; i < AUDIT_NR_FILTERS; i++) { | |
e45aa212 AV |
1431 | list_for_each_entry_safe(r, n, &audit_rules_list[i], list) { |
1432 | int res = update_lsm_rule(r); | |
1a9d0797 AV |
1433 | if (!err) |
1434 | err = res; | |
3dc7e315 DG |
1435 | } |
1436 | } | |
f368c07d | 1437 | mutex_unlock(&audit_filter_mutex); |
3dc7e315 DG |
1438 | |
1439 | return err; | |
1440 | } |