Commit | Line | Data |
---|---|---|
1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
fe7752ba DW |
2 | /* auditfilter.c -- filtering of audit events |
3 | * | |
4 | * Copyright 2003-2004 Red Hat, Inc. | |
5 | * Copyright 2005 Hewlett-Packard Development Company, L.P. | |
6 | * Copyright 2005 IBM Corporation | |
fe7752ba DW |
7 | */ |
8 | ||
f952d10f RGB |
9 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
10 | ||
fe7752ba DW |
11 | #include <linux/kernel.h> |
12 | #include <linux/audit.h> | |
13 | #include <linux/kthread.h> | |
f368c07d AG |
14 | #include <linux/mutex.h> |
15 | #include <linux/fs.h> | |
16 | #include <linux/namei.h> | |
fe7752ba | 17 | #include <linux/netlink.h> |
f368c07d | 18 | #include <linux/sched.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
2a862b32 | 20 | #include <linux/security.h> |
48095d99 | 21 | #include <net/net_namespace.h> |
6f285b19 | 22 | #include <net/sock.h> |
fe7752ba DW |
23 | #include "audit.h" |
24 | ||
f368c07d AG |
25 | /* |
26 | * Locking model: | |
27 | * | |
28 | * audit_filter_mutex: | |
725131ef SM |
29 | * Synchronizes writes and blocking reads of audit's filterlist |
30 | * data. Rcu is used to traverse the filterlist and access | |
31 | * contents of structs audit_entry, audit_watch and opaque | |
32 | * LSM rules during filtering. If modified, these structures | |
33 | * must be copied and replace their counterparts in the filterlist. | |
34 | * An audit_parent struct is not accessed during filtering, so may | |
35 | * be written directly provided audit_filter_mutex is held. | |
f368c07d AG |
36 | */ |
37 | ||
f368c07d | 38 | /* Audit filter lists, defined in <linux/audit.h> */ |
fe7752ba DW |
39 | struct list_head audit_filter_list[AUDIT_NR_FILTERS] = { |
40 | LIST_HEAD_INIT(audit_filter_list[0]), | |
41 | LIST_HEAD_INIT(audit_filter_list[1]), | |
42 | LIST_HEAD_INIT(audit_filter_list[2]), | |
43 | LIST_HEAD_INIT(audit_filter_list[3]), | |
44 | LIST_HEAD_INIT(audit_filter_list[4]), | |
45 | LIST_HEAD_INIT(audit_filter_list[5]), | |
42d5e376 RGB |
46 | LIST_HEAD_INIT(audit_filter_list[6]), |
47 | #if AUDIT_NR_FILTERS != 7 | |
fe7752ba DW |
48 | #error Fix audit_filter_list initialiser |
49 | #endif | |
50 | }; | |
e45aa212 AV |
51 | static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = { |
52 | LIST_HEAD_INIT(audit_rules_list[0]), | |
53 | LIST_HEAD_INIT(audit_rules_list[1]), | |
54 | LIST_HEAD_INIT(audit_rules_list[2]), | |
55 | LIST_HEAD_INIT(audit_rules_list[3]), | |
56 | LIST_HEAD_INIT(audit_rules_list[4]), | |
57 | LIST_HEAD_INIT(audit_rules_list[5]), | |
42d5e376 | 58 | LIST_HEAD_INIT(audit_rules_list[6]), |
e45aa212 | 59 | }; |
fe7752ba | 60 | |
74c3cbe3 | 61 | DEFINE_MUTEX(audit_filter_mutex); |
f368c07d | 62 | |
219ca394 RGB |
63 | static void audit_free_lsm_field(struct audit_field *f) |
64 | { | |
65 | switch (f->type) { | |
66 | case AUDIT_SUBJ_USER: | |
67 | case AUDIT_SUBJ_ROLE: | |
68 | case AUDIT_SUBJ_TYPE: | |
69 | case AUDIT_SUBJ_SEN: | |
70 | case AUDIT_SUBJ_CLR: | |
71 | case AUDIT_OBJ_USER: | |
72 | case AUDIT_OBJ_ROLE: | |
73 | case AUDIT_OBJ_TYPE: | |
74 | case AUDIT_OBJ_LEV_LOW: | |
75 | case AUDIT_OBJ_LEV_HIGH: | |
76 | kfree(f->lsm_str); | |
77 | security_audit_rule_free(f->lsm_rule); | |
78 | } | |
79 | } | |
80 | ||
93315ed6 | 81 | static inline void audit_free_rule(struct audit_entry *e) |
fe7752ba | 82 | { |
3dc7e315 | 83 | int i; |
c28bb7da | 84 | struct audit_krule *erule = &e->rule; |
ae7b8f41 | 85 | |
f368c07d | 86 | /* some rules don't have associated watches */ |
c28bb7da ZX |
87 | if (erule->watch) |
88 | audit_put_watch(erule->watch); | |
89 | if (erule->fields) | |
219ca394 RGB |
90 | for (i = 0; i < erule->field_count; i++) |
91 | audit_free_lsm_field(&erule->fields[i]); | |
c28bb7da ZX |
92 | kfree(erule->fields); |
93 | kfree(erule->filterkey); | |
93315ed6 AG |
94 | kfree(e); |
95 | } | |
96 | ||
74c3cbe3 | 97 | void audit_free_rule_rcu(struct rcu_head *head) |
93315ed6 AG |
98 | { |
99 | struct audit_entry *e = container_of(head, struct audit_entry, rcu); | |
100 | audit_free_rule(e); | |
101 | } | |
102 | ||
3dc7e315 DG |
103 | /* Initialize an audit filterlist entry. */ |
104 | static inline struct audit_entry *audit_init_entry(u32 field_count) | |
105 | { | |
106 | struct audit_entry *entry; | |
107 | struct audit_field *fields; | |
108 | ||
109 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
110 | if (unlikely(!entry)) | |
111 | return NULL; | |
112 | ||
bab5e2d6 | 113 | fields = kcalloc(field_count, sizeof(*fields), GFP_KERNEL); |
3dc7e315 DG |
114 | if (unlikely(!fields)) { |
115 | kfree(entry); | |
116 | return NULL; | |
117 | } | |
118 | entry->rule.fields = fields; | |
119 | ||
120 | return entry; | |
121 | } | |
122 | ||
93315ed6 AG |
123 | /* Unpack a filter field's string representation from user-space |
124 | * buffer. */ | |
74c3cbe3 | 125 | char *audit_unpack_string(void **bufp, size_t *remain, size_t len) |
93315ed6 AG |
126 | { |
127 | char *str; | |
128 | ||
129 | if (!*bufp || (len == 0) || (len > *remain)) | |
130 | return ERR_PTR(-EINVAL); | |
131 | ||
132 | /* Of the currently implemented string fields, PATH_MAX | |
133 | * defines the longest valid length. | |
134 | */ | |
135 | if (len > PATH_MAX) | |
136 | return ERR_PTR(-ENAMETOOLONG); | |
137 | ||
138 | str = kmalloc(len + 1, GFP_KERNEL); | |
139 | if (unlikely(!str)) | |
140 | return ERR_PTR(-ENOMEM); | |
141 | ||
142 | memcpy(str, *bufp, len); | |
143 | str[len] = 0; | |
144 | *bufp += len; | |
145 | *remain -= len; | |
146 | ||
147 | return str; | |
148 | } | |
149 | ||
fd97646b | 150 | /* Translate an inode field to kernel representation. */ |
f368c07d AG |
151 | static inline int audit_to_inode(struct audit_krule *krule, |
152 | struct audit_field *f) | |
153 | { | |
154 | if (krule->listnr != AUDIT_FILTER_EXIT || | |
3639f170 | 155 | krule->inode_f || krule->watch || krule->tree || |
5af75d8d | 156 | (f->op != Audit_equal && f->op != Audit_not_equal)) |
f368c07d AG |
157 | return -EINVAL; |
158 | ||
159 | krule->inode_f = f; | |
160 | return 0; | |
161 | } | |
162 | ||
b915543b AV |
163 | static __u32 *classes[AUDIT_SYSCALL_CLASSES]; |
164 | ||
165 | int __init audit_register_class(int class, unsigned *list) | |
166 | { | |
bab5e2d6 | 167 | __u32 *p = kcalloc(AUDIT_BITMASK_SIZE, sizeof(__u32), GFP_KERNEL); |
b915543b AV |
168 | if (!p) |
169 | return -ENOMEM; | |
170 | while (*list != ~0U) { | |
171 | unsigned n = *list++; | |
172 | if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { | |
173 | kfree(p); | |
174 | return -EINVAL; | |
175 | } | |
176 | p[AUDIT_WORD(n)] |= AUDIT_BIT(n); | |
177 | } | |
178 | if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { | |
179 | kfree(p); | |
180 | return -EINVAL; | |
181 | } | |
182 | classes[class] = p; | |
183 | return 0; | |
184 | } | |
185 | ||
55669bfa AV |
186 | int audit_match_class(int class, unsigned syscall) |
187 | { | |
c926e4f4 | 188 | if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32)) |
55669bfa AV |
189 | return 0; |
190 | if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) | |
191 | return 0; | |
192 | return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); | |
193 | } | |
194 | ||
327b9eeb | 195 | #ifdef CONFIG_AUDITSYSCALL |
e54dc243 AG |
196 | static inline int audit_match_class_bits(int class, u32 *mask) |
197 | { | |
198 | int i; | |
199 | ||
200 | if (classes[class]) { | |
201 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
202 | if (mask[i] & classes[class][i]) | |
203 | return 0; | |
204 | } | |
205 | return 1; | |
206 | } | |
207 | ||
208 | static int audit_match_signal(struct audit_entry *entry) | |
209 | { | |
210 | struct audit_field *arch = entry->rule.arch_f; | |
211 | ||
212 | if (!arch) { | |
213 | /* When arch is unspecified, we must check both masks on biarch | |
214 | * as syscall number alone is ambiguous. */ | |
215 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
216 | entry->rule.mask) && | |
217 | audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
218 | entry->rule.mask)); | |
219 | } | |
220 | ||
221 | switch(audit_classify_arch(arch->val)) { | |
222 | case 0: /* native */ | |
223 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, | |
224 | entry->rule.mask)); | |
225 | case 1: /* 32bit on biarch */ | |
226 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, | |
227 | entry->rule.mask)); | |
228 | default: | |
229 | return 1; | |
230 | } | |
231 | } | |
327b9eeb | 232 | #endif |
e54dc243 | 233 | |
93315ed6 | 234 | /* Common user-space to kernel rule translation. */ |
56c4911a | 235 | static inline struct audit_entry *audit_to_entry_common(struct audit_rule_data *rule) |
93315ed6 AG |
236 | { |
237 | unsigned listnr; | |
238 | struct audit_entry *entry; | |
93315ed6 AG |
239 | int i, err; |
240 | ||
241 | err = -EINVAL; | |
242 | listnr = rule->flags & ~AUDIT_FILTER_PREPEND; | |
243 | switch(listnr) { | |
244 | default: | |
245 | goto exit_err; | |
93315ed6 AG |
246 | #ifdef CONFIG_AUDITSYSCALL |
247 | case AUDIT_FILTER_ENTRY: | |
5260ecc2 RGB |
248 | pr_err("AUDIT_FILTER_ENTRY is deprecated\n"); |
249 | goto exit_err; | |
93315ed6 AG |
250 | case AUDIT_FILTER_EXIT: |
251 | case AUDIT_FILTER_TASK: | |
252 | #endif | |
7ff68e53 | 253 | case AUDIT_FILTER_USER: |
d904ac03 | 254 | case AUDIT_FILTER_EXCLUDE: |
42d5e376 | 255 | case AUDIT_FILTER_FS: |
93315ed6 AG |
256 | ; |
257 | } | |
014149cc | 258 | if (unlikely(rule->action == AUDIT_POSSIBLE)) { |
f952d10f | 259 | pr_err("AUDIT_POSSIBLE is deprecated\n"); |
014149cc AV |
260 | goto exit_err; |
261 | } | |
262 | if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS) | |
93315ed6 AG |
263 | goto exit_err; |
264 | if (rule->field_count > AUDIT_MAX_FIELDS) | |
265 | goto exit_err; | |
266 | ||
267 | err = -ENOMEM; | |
3dc7e315 DG |
268 | entry = audit_init_entry(rule->field_count); |
269 | if (!entry) | |
93315ed6 | 270 | goto exit_err; |
93315ed6 AG |
271 | |
272 | entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND; | |
273 | entry->rule.listnr = listnr; | |
274 | entry->rule.action = rule->action; | |
275 | entry->rule.field_count = rule->field_count; | |
93315ed6 AG |
276 | |
277 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
278 | entry->rule.mask[i] = rule->mask[i]; | |
279 | ||
b915543b AV |
280 | for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { |
281 | int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; | |
282 | __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; | |
283 | __u32 *class; | |
284 | ||
285 | if (!(*p & AUDIT_BIT(bit))) | |
286 | continue; | |
287 | *p &= ~AUDIT_BIT(bit); | |
288 | class = classes[i]; | |
289 | if (class) { | |
290 | int j; | |
291 | for (j = 0; j < AUDIT_BITMASK_SIZE; j++) | |
292 | entry->rule.mask[j] |= class[j]; | |
293 | } | |
294 | } | |
295 | ||
93315ed6 AG |
296 | return entry; |
297 | ||
298 | exit_err: | |
299 | return ERR_PTR(err); | |
300 | } | |
301 | ||
5af75d8d AV |
302 | static u32 audit_ops[] = |
303 | { | |
304 | [Audit_equal] = AUDIT_EQUAL, | |
305 | [Audit_not_equal] = AUDIT_NOT_EQUAL, | |
306 | [Audit_bitmask] = AUDIT_BIT_MASK, | |
307 | [Audit_bittest] = AUDIT_BIT_TEST, | |
308 | [Audit_lt] = AUDIT_LESS_THAN, | |
309 | [Audit_gt] = AUDIT_GREATER_THAN, | |
310 | [Audit_le] = AUDIT_LESS_THAN_OR_EQUAL, | |
311 | [Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL, | |
312 | }; | |
313 | ||
314 | static u32 audit_to_op(u32 op) | |
315 | { | |
316 | u32 n; | |
317 | for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++) | |
318 | ; | |
319 | return n; | |
320 | } | |
321 | ||
ab61d38e | 322 | /* check if an audit field is valid */ |
62062cf8 | 323 | static int audit_field_valid(struct audit_entry *entry, struct audit_field *f) |
93315ed6 | 324 | { |
62062cf8 EP |
325 | switch(f->type) { |
326 | case AUDIT_MSGTYPE: | |
d904ac03 | 327 | if (entry->rule.listnr != AUDIT_FILTER_EXCLUDE && |
62062cf8 EP |
328 | entry->rule.listnr != AUDIT_FILTER_USER) |
329 | return -EINVAL; | |
330 | break; | |
42d5e376 RGB |
331 | case AUDIT_FSTYPE: |
332 | if (entry->rule.listnr != AUDIT_FILTER_FS) | |
333 | return -EINVAL; | |
334 | break; | |
335 | } | |
336 | ||
337 | switch(entry->rule.listnr) { | |
338 | case AUDIT_FILTER_FS: | |
339 | switch(f->type) { | |
340 | case AUDIT_FSTYPE: | |
341 | case AUDIT_FILTERKEY: | |
342 | break; | |
343 | default: | |
344 | return -EINVAL; | |
345 | } | |
b7a84dea | 346 | } |
93315ed6 | 347 | |
ab61d38e EP |
348 | switch(f->type) { |
349 | default: | |
350 | return -EINVAL; | |
351 | case AUDIT_UID: | |
352 | case AUDIT_EUID: | |
353 | case AUDIT_SUID: | |
354 | case AUDIT_FSUID: | |
355 | case AUDIT_LOGINUID: | |
356 | case AUDIT_OBJ_UID: | |
357 | case AUDIT_GID: | |
358 | case AUDIT_EGID: | |
359 | case AUDIT_SGID: | |
360 | case AUDIT_FSGID: | |
361 | case AUDIT_OBJ_GID: | |
362 | case AUDIT_PID: | |
363 | case AUDIT_PERS: | |
364 | case AUDIT_MSGTYPE: | |
365 | case AUDIT_PPID: | |
366 | case AUDIT_DEVMAJOR: | |
367 | case AUDIT_DEVMINOR: | |
368 | case AUDIT_EXIT: | |
369 | case AUDIT_SUCCESS: | |
78122037 | 370 | case AUDIT_INODE: |
8fae4770 | 371 | case AUDIT_SESSIONID: |
ab61d38e EP |
372 | /* bit ops are only useful on syscall args */ |
373 | if (f->op == Audit_bitmask || f->op == Audit_bittest) | |
374 | return -EINVAL; | |
375 | break; | |
376 | case AUDIT_ARG0: | |
377 | case AUDIT_ARG1: | |
378 | case AUDIT_ARG2: | |
379 | case AUDIT_ARG3: | |
380 | case AUDIT_SUBJ_USER: | |
381 | case AUDIT_SUBJ_ROLE: | |
382 | case AUDIT_SUBJ_TYPE: | |
383 | case AUDIT_SUBJ_SEN: | |
384 | case AUDIT_SUBJ_CLR: | |
385 | case AUDIT_OBJ_USER: | |
386 | case AUDIT_OBJ_ROLE: | |
387 | case AUDIT_OBJ_TYPE: | |
388 | case AUDIT_OBJ_LEV_LOW: | |
389 | case AUDIT_OBJ_LEV_HIGH: | |
390 | case AUDIT_WATCH: | |
391 | case AUDIT_DIR: | |
392 | case AUDIT_FILTERKEY: | |
393 | break; | |
780a7654 EB |
394 | case AUDIT_LOGINUID_SET: |
395 | if ((f->val != 0) && (f->val != 1)) | |
396 | return -EINVAL; | |
397 | /* FALL THROUGH */ | |
ab61d38e | 398 | case AUDIT_ARCH: |
42d5e376 | 399 | case AUDIT_FSTYPE: |
ab61d38e EP |
400 | if (f->op != Audit_not_equal && f->op != Audit_equal) |
401 | return -EINVAL; | |
402 | break; | |
403 | case AUDIT_PERM: | |
404 | if (f->val & ~15) | |
405 | return -EINVAL; | |
406 | break; | |
407 | case AUDIT_FILETYPE: | |
408 | if (f->val & ~S_IFMT) | |
409 | return -EINVAL; | |
410 | break; | |
411 | case AUDIT_FIELD_COMPARE: | |
412 | if (f->val > AUDIT_MAX_FIELD_COMPARE) | |
413 | return -EINVAL; | |
414 | break; | |
34d99af5 | 415 | case AUDIT_EXE: |
23bcc480 | 416 | if (f->op != Audit_not_equal && f->op != Audit_equal) |
34d99af5 | 417 | return -EINVAL; |
34d99af5 | 418 | break; |
b7a84dea | 419 | } |
62062cf8 | 420 | return 0; |
fe7752ba DW |
421 | } |
422 | ||
fd97646b | 423 | /* Translate struct audit_rule_data to kernel's rule representation. */ |
93315ed6 AG |
424 | static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, |
425 | size_t datasz) | |
fe7752ba | 426 | { |
93315ed6 AG |
427 | int err = 0; |
428 | struct audit_entry *entry; | |
429 | void *bufp; | |
3dc7e315 | 430 | size_t remain = datasz - sizeof(struct audit_rule_data); |
fe7752ba | 431 | int i; |
3dc7e315 | 432 | char *str; |
34d99af5 | 433 | struct audit_fsnotify_mark *audit_mark; |
fe7752ba | 434 | |
56c4911a | 435 | entry = audit_to_entry_common(data); |
93315ed6 AG |
436 | if (IS_ERR(entry)) |
437 | goto exit_nofree; | |
fe7752ba | 438 | |
93315ed6 | 439 | bufp = data->buf; |
93315ed6 AG |
440 | for (i = 0; i < data->field_count; i++) { |
441 | struct audit_field *f = &entry->rule.fields[i]; | |
442 | ||
443 | err = -EINVAL; | |
5af75d8d AV |
444 | |
445 | f->op = audit_to_op(data->fieldflags[i]); | |
446 | if (f->op == Audit_bad) | |
93315ed6 AG |
447 | goto exit_free; |
448 | ||
93315ed6 | 449 | f->type = data->fields[i]; |
3dc7e315 | 450 | f->val = data->values[i]; |
62062cf8 | 451 | |
780a7654 | 452 | /* Support legacy tests for a valid loginuid */ |
42f74461 | 453 | if ((f->type == AUDIT_LOGINUID) && (f->val == AUDIT_UID_UNSET)) { |
780a7654 EB |
454 | f->type = AUDIT_LOGINUID_SET; |
455 | f->val = 0; | |
041d7b98 | 456 | entry->rule.pflags |= AUDIT_LOGINUID_LEGACY; |
f1dc4867 RGB |
457 | } |
458 | ||
62062cf8 EP |
459 | err = audit_field_valid(entry, f); |
460 | if (err) | |
461 | goto exit_free; | |
462 | ||
463 | err = -EINVAL; | |
ab61d38e | 464 | switch (f->type) { |
780a7654 | 465 | case AUDIT_LOGINUID: |
0a73dccc AV |
466 | case AUDIT_UID: |
467 | case AUDIT_EUID: | |
468 | case AUDIT_SUID: | |
469 | case AUDIT_FSUID: | |
ca57ec0f | 470 | case AUDIT_OBJ_UID: |
ca57ec0f EB |
471 | f->uid = make_kuid(current_user_ns(), f->val); |
472 | if (!uid_valid(f->uid)) | |
473 | goto exit_free; | |
474 | break; | |
0a73dccc AV |
475 | case AUDIT_GID: |
476 | case AUDIT_EGID: | |
477 | case AUDIT_SGID: | |
478 | case AUDIT_FSGID: | |
ca57ec0f | 479 | case AUDIT_OBJ_GID: |
ca57ec0f EB |
480 | f->gid = make_kgid(current_user_ns(), f->val); |
481 | if (!gid_valid(f->gid)) | |
482 | goto exit_free; | |
483 | break; | |
e54dc243 AG |
484 | case AUDIT_ARCH: |
485 | entry->rule.arch_f = f; | |
486 | break; | |
3a6b9f85 DG |
487 | case AUDIT_SUBJ_USER: |
488 | case AUDIT_SUBJ_ROLE: | |
489 | case AUDIT_SUBJ_TYPE: | |
490 | case AUDIT_SUBJ_SEN: | |
491 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
492 | case AUDIT_OBJ_USER: |
493 | case AUDIT_OBJ_ROLE: | |
494 | case AUDIT_OBJ_TYPE: | |
495 | case AUDIT_OBJ_LEV_LOW: | |
496 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 DG |
497 | str = audit_unpack_string(&bufp, &remain, f->val); |
498 | if (IS_ERR(str)) | |
499 | goto exit_free; | |
500 | entry->rule.buflen += f->val; | |
501 | ||
d7a96f3a | 502 | err = security_audit_rule_init(f->type, f->op, str, |
04305e4a | 503 | (void **)&f->lsm_rule); |
3dc7e315 DG |
504 | /* Keep currently invalid fields around in case they |
505 | * become valid after a policy reload. */ | |
506 | if (err == -EINVAL) { | |
f952d10f RGB |
507 | pr_warn("audit rule for LSM \'%s\' is invalid\n", |
508 | str); | |
3dc7e315 DG |
509 | err = 0; |
510 | } | |
511 | if (err) { | |
512 | kfree(str); | |
513 | goto exit_free; | |
514 | } else | |
04305e4a | 515 | f->lsm_str = str; |
3dc7e315 | 516 | break; |
f368c07d AG |
517 | case AUDIT_WATCH: |
518 | str = audit_unpack_string(&bufp, &remain, f->val); | |
519 | if (IS_ERR(str)) | |
520 | goto exit_free; | |
521 | entry->rule.buflen += f->val; | |
522 | ||
523 | err = audit_to_watch(&entry->rule, str, f->val, f->op); | |
524 | if (err) { | |
525 | kfree(str); | |
526 | goto exit_free; | |
527 | } | |
528 | break; | |
74c3cbe3 AV |
529 | case AUDIT_DIR: |
530 | str = audit_unpack_string(&bufp, &remain, f->val); | |
531 | if (IS_ERR(str)) | |
532 | goto exit_free; | |
533 | entry->rule.buflen += f->val; | |
534 | ||
535 | err = audit_make_tree(&entry->rule, str, f->op); | |
536 | kfree(str); | |
537 | if (err) | |
538 | goto exit_free; | |
539 | break; | |
f368c07d AG |
540 | case AUDIT_INODE: |
541 | err = audit_to_inode(&entry->rule, f); | |
542 | if (err) | |
543 | goto exit_free; | |
544 | break; | |
5adc8a6a | 545 | case AUDIT_FILTERKEY: |
5adc8a6a AG |
546 | if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN) |
547 | goto exit_free; | |
548 | str = audit_unpack_string(&bufp, &remain, f->val); | |
549 | if (IS_ERR(str)) | |
550 | goto exit_free; | |
551 | entry->rule.buflen += f->val; | |
552 | entry->rule.filterkey = str; | |
553 | break; | |
34d99af5 RGB |
554 | case AUDIT_EXE: |
555 | if (entry->rule.exe || f->val > PATH_MAX) | |
556 | goto exit_free; | |
557 | str = audit_unpack_string(&bufp, &remain, f->val); | |
558 | if (IS_ERR(str)) { | |
559 | err = PTR_ERR(str); | |
560 | goto exit_free; | |
561 | } | |
562 | entry->rule.buflen += f->val; | |
563 | ||
564 | audit_mark = audit_alloc_mark(&entry->rule, str, f->val); | |
565 | if (IS_ERR(audit_mark)) { | |
566 | kfree(str); | |
567 | err = PTR_ERR(audit_mark); | |
568 | goto exit_free; | |
569 | } | |
570 | entry->rule.exe = audit_mark; | |
571 | break; | |
f368c07d AG |
572 | } |
573 | } | |
574 | ||
5af75d8d AV |
575 | if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal) |
576 | entry->rule.inode_f = NULL; | |
93315ed6 AG |
577 | |
578 | exit_nofree: | |
579 | return entry; | |
580 | ||
581 | exit_free: | |
373e0f34 CG |
582 | if (entry->rule.tree) |
583 | audit_put_tree(entry->rule.tree); /* that's the temporary one */ | |
34d99af5 RGB |
584 | if (entry->rule.exe) |
585 | audit_remove_mark(entry->rule.exe); /* that's the template one */ | |
93315ed6 AG |
586 | audit_free_rule(entry); |
587 | return ERR_PTR(err); | |
588 | } | |
589 | ||
590 | /* Pack a filter field's string representation into data block. */ | |
74c3cbe3 | 591 | static inline size_t audit_pack_string(void **bufp, const char *str) |
93315ed6 AG |
592 | { |
593 | size_t len = strlen(str); | |
594 | ||
595 | memcpy(*bufp, str, len); | |
596 | *bufp += len; | |
597 | ||
598 | return len; | |
599 | } | |
600 | ||
fd97646b | 601 | /* Translate kernel rule representation to struct audit_rule_data. */ |
93315ed6 AG |
602 | static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) |
603 | { | |
604 | struct audit_rule_data *data; | |
605 | void *bufp; | |
606 | int i; | |
607 | ||
608 | data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); | |
609 | if (unlikely(!data)) | |
0a3b483e | 610 | return NULL; |
93315ed6 AG |
611 | memset(data, 0, sizeof(*data)); |
612 | ||
613 | data->flags = krule->flags | krule->listnr; | |
614 | data->action = krule->action; | |
615 | data->field_count = krule->field_count; | |
616 | bufp = data->buf; | |
617 | for (i = 0; i < data->field_count; i++) { | |
618 | struct audit_field *f = &krule->fields[i]; | |
619 | ||
620 | data->fields[i] = f->type; | |
5af75d8d | 621 | data->fieldflags[i] = audit_ops[f->op]; |
93315ed6 | 622 | switch(f->type) { |
3a6b9f85 DG |
623 | case AUDIT_SUBJ_USER: |
624 | case AUDIT_SUBJ_ROLE: | |
625 | case AUDIT_SUBJ_TYPE: | |
626 | case AUDIT_SUBJ_SEN: | |
627 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
628 | case AUDIT_OBJ_USER: |
629 | case AUDIT_OBJ_ROLE: | |
630 | case AUDIT_OBJ_TYPE: | |
631 | case AUDIT_OBJ_LEV_LOW: | |
632 | case AUDIT_OBJ_LEV_HIGH: | |
3dc7e315 | 633 | data->buflen += data->values[i] = |
04305e4a | 634 | audit_pack_string(&bufp, f->lsm_str); |
3dc7e315 | 635 | break; |
f368c07d AG |
636 | case AUDIT_WATCH: |
637 | data->buflen += data->values[i] = | |
cfcad62c EP |
638 | audit_pack_string(&bufp, |
639 | audit_watch_path(krule->watch)); | |
f368c07d | 640 | break; |
74c3cbe3 AV |
641 | case AUDIT_DIR: |
642 | data->buflen += data->values[i] = | |
643 | audit_pack_string(&bufp, | |
644 | audit_tree_path(krule->tree)); | |
645 | break; | |
5adc8a6a AG |
646 | case AUDIT_FILTERKEY: |
647 | data->buflen += data->values[i] = | |
648 | audit_pack_string(&bufp, krule->filterkey); | |
649 | break; | |
34d99af5 RGB |
650 | case AUDIT_EXE: |
651 | data->buflen += data->values[i] = | |
652 | audit_pack_string(&bufp, audit_mark_path(krule->exe)); | |
653 | break; | |
041d7b98 RGB |
654 | case AUDIT_LOGINUID_SET: |
655 | if (krule->pflags & AUDIT_LOGINUID_LEGACY && !f->val) { | |
656 | data->fields[i] = AUDIT_LOGINUID; | |
657 | data->values[i] = AUDIT_UID_UNSET; | |
658 | break; | |
659 | } | |
131d34cb | 660 | /* fall through - if set */ |
93315ed6 AG |
661 | default: |
662 | data->values[i] = f->val; | |
663 | } | |
664 | } | |
665 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i]; | |
666 | ||
667 | return data; | |
668 | } | |
669 | ||
670 | /* Compare two rules in kernel format. Considered success if rules | |
671 | * don't match. */ | |
672 | static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) | |
673 | { | |
674 | int i; | |
675 | ||
676 | if (a->flags != b->flags || | |
041d7b98 | 677 | a->pflags != b->pflags || |
93315ed6 AG |
678 | a->listnr != b->listnr || |
679 | a->action != b->action || | |
680 | a->field_count != b->field_count) | |
fe7752ba DW |
681 | return 1; |
682 | ||
683 | for (i = 0; i < a->field_count; i++) { | |
93315ed6 AG |
684 | if (a->fields[i].type != b->fields[i].type || |
685 | a->fields[i].op != b->fields[i].op) | |
fe7752ba | 686 | return 1; |
93315ed6 AG |
687 | |
688 | switch(a->fields[i].type) { | |
3a6b9f85 DG |
689 | case AUDIT_SUBJ_USER: |
690 | case AUDIT_SUBJ_ROLE: | |
691 | case AUDIT_SUBJ_TYPE: | |
692 | case AUDIT_SUBJ_SEN: | |
693 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
694 | case AUDIT_OBJ_USER: |
695 | case AUDIT_OBJ_ROLE: | |
696 | case AUDIT_OBJ_TYPE: | |
697 | case AUDIT_OBJ_LEV_LOW: | |
698 | case AUDIT_OBJ_LEV_HIGH: | |
04305e4a | 699 | if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str)) |
3dc7e315 DG |
700 | return 1; |
701 | break; | |
f368c07d | 702 | case AUDIT_WATCH: |
cfcad62c EP |
703 | if (strcmp(audit_watch_path(a->watch), |
704 | audit_watch_path(b->watch))) | |
f368c07d AG |
705 | return 1; |
706 | break; | |
74c3cbe3 AV |
707 | case AUDIT_DIR: |
708 | if (strcmp(audit_tree_path(a->tree), | |
709 | audit_tree_path(b->tree))) | |
710 | return 1; | |
711 | break; | |
5adc8a6a AG |
712 | case AUDIT_FILTERKEY: |
713 | /* both filterkeys exist based on above type compare */ | |
714 | if (strcmp(a->filterkey, b->filterkey)) | |
715 | return 1; | |
716 | break; | |
34d99af5 RGB |
717 | case AUDIT_EXE: |
718 | /* both paths exist based on above type compare */ | |
719 | if (strcmp(audit_mark_path(a->exe), | |
720 | audit_mark_path(b->exe))) | |
721 | return 1; | |
722 | break; | |
ca57ec0f EB |
723 | case AUDIT_UID: |
724 | case AUDIT_EUID: | |
725 | case AUDIT_SUID: | |
726 | case AUDIT_FSUID: | |
727 | case AUDIT_LOGINUID: | |
728 | case AUDIT_OBJ_UID: | |
729 | if (!uid_eq(a->fields[i].uid, b->fields[i].uid)) | |
730 | return 1; | |
731 | break; | |
732 | case AUDIT_GID: | |
733 | case AUDIT_EGID: | |
734 | case AUDIT_SGID: | |
735 | case AUDIT_FSGID: | |
736 | case AUDIT_OBJ_GID: | |
737 | if (!gid_eq(a->fields[i].gid, b->fields[i].gid)) | |
738 | return 1; | |
739 | break; | |
93315ed6 AG |
740 | default: |
741 | if (a->fields[i].val != b->fields[i].val) | |
742 | return 1; | |
743 | } | |
fe7752ba DW |
744 | } |
745 | ||
746 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
747 | if (a->mask[i] != b->mask[i]) | |
748 | return 1; | |
749 | ||
750 | return 0; | |
751 | } | |
752 | ||
04305e4a | 753 | /* Duplicate LSM field information. The lsm_rule is opaque, so must be |
3dc7e315 | 754 | * re-initialized. */ |
d7a96f3a | 755 | static inline int audit_dupe_lsm_field(struct audit_field *df, |
3dc7e315 DG |
756 | struct audit_field *sf) |
757 | { | |
758 | int ret = 0; | |
04305e4a | 759 | char *lsm_str; |
3dc7e315 | 760 | |
04305e4a AD |
761 | /* our own copy of lsm_str */ |
762 | lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL); | |
763 | if (unlikely(!lsm_str)) | |
3e1fbd12 | 764 | return -ENOMEM; |
04305e4a | 765 | df->lsm_str = lsm_str; |
3dc7e315 | 766 | |
04305e4a AD |
767 | /* our own (refreshed) copy of lsm_rule */ |
768 | ret = security_audit_rule_init(df->type, df->op, df->lsm_str, | |
769 | (void **)&df->lsm_rule); | |
3dc7e315 DG |
770 | /* Keep currently invalid fields around in case they |
771 | * become valid after a policy reload. */ | |
772 | if (ret == -EINVAL) { | |
f952d10f RGB |
773 | pr_warn("audit rule for LSM \'%s\' is invalid\n", |
774 | df->lsm_str); | |
3dc7e315 DG |
775 | ret = 0; |
776 | } | |
777 | ||
778 | return ret; | |
779 | } | |
780 | ||
781 | /* Duplicate an audit rule. This will be a deep copy with the exception | |
d7a96f3a | 782 | * of the watch - that pointer is carried over. The LSM specific fields |
3dc7e315 | 783 | * will be updated in the copy. The point is to be able to replace the old |
f368c07d AG |
784 | * rule with the new rule in the filterlist, then free the old rule. |
785 | * The rlist element is undefined; list manipulations are handled apart from | |
786 | * the initial copy. */ | |
ae7b8f41 | 787 | struct audit_entry *audit_dupe_rule(struct audit_krule *old) |
3dc7e315 DG |
788 | { |
789 | u32 fcount = old->field_count; | |
790 | struct audit_entry *entry; | |
791 | struct audit_krule *new; | |
5adc8a6a | 792 | char *fk; |
3dc7e315 DG |
793 | int i, err = 0; |
794 | ||
795 | entry = audit_init_entry(fcount); | |
796 | if (unlikely(!entry)) | |
797 | return ERR_PTR(-ENOMEM); | |
798 | ||
799 | new = &entry->rule; | |
3dc7e315 | 800 | new->flags = old->flags; |
041d7b98 | 801 | new->pflags = old->pflags; |
3dc7e315 DG |
802 | new->listnr = old->listnr; |
803 | new->action = old->action; | |
804 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
805 | new->mask[i] = old->mask[i]; | |
0590b933 | 806 | new->prio = old->prio; |
3dc7e315 | 807 | new->buflen = old->buflen; |
f368c07d | 808 | new->inode_f = old->inode_f; |
3dc7e315 | 809 | new->field_count = old->field_count; |
ae7b8f41 | 810 | |
74c3cbe3 AV |
811 | /* |
812 | * note that we are OK with not refcounting here; audit_match_tree() | |
813 | * never dereferences tree and we can't get false positives there | |
814 | * since we'd have to have rule gone from the list *and* removed | |
815 | * before the chunks found by lookup had been allocated, i.e. before | |
816 | * the beginning of list scan. | |
817 | */ | |
818 | new->tree = old->tree; | |
3dc7e315 DG |
819 | memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount); |
820 | ||
04305e4a | 821 | /* deep copy this information, updating the lsm_rule fields, because |
3dc7e315 DG |
822 | * the originals will all be freed when the old rule is freed. */ |
823 | for (i = 0; i < fcount; i++) { | |
824 | switch (new->fields[i].type) { | |
3a6b9f85 DG |
825 | case AUDIT_SUBJ_USER: |
826 | case AUDIT_SUBJ_ROLE: | |
827 | case AUDIT_SUBJ_TYPE: | |
828 | case AUDIT_SUBJ_SEN: | |
829 | case AUDIT_SUBJ_CLR: | |
6e5a2d1d DG |
830 | case AUDIT_OBJ_USER: |
831 | case AUDIT_OBJ_ROLE: | |
832 | case AUDIT_OBJ_TYPE: | |
833 | case AUDIT_OBJ_LEV_LOW: | |
834 | case AUDIT_OBJ_LEV_HIGH: | |
d7a96f3a | 835 | err = audit_dupe_lsm_field(&new->fields[i], |
3dc7e315 | 836 | &old->fields[i]); |
5adc8a6a AG |
837 | break; |
838 | case AUDIT_FILTERKEY: | |
839 | fk = kstrdup(old->filterkey, GFP_KERNEL); | |
840 | if (unlikely(!fk)) | |
841 | err = -ENOMEM; | |
842 | else | |
843 | new->filterkey = fk; | |
34d99af5 RGB |
844 | break; |
845 | case AUDIT_EXE: | |
846 | err = audit_dupe_exe(new, old); | |
847 | break; | |
3dc7e315 DG |
848 | } |
849 | if (err) { | |
34d99af5 RGB |
850 | if (new->exe) |
851 | audit_remove_mark(new->exe); | |
3dc7e315 DG |
852 | audit_free_rule(entry); |
853 | return ERR_PTR(err); | |
854 | } | |
855 | } | |
856 | ||
ae7b8f41 EP |
857 | if (old->watch) { |
858 | audit_get_watch(old->watch); | |
859 | new->watch = old->watch; | |
f368c07d AG |
860 | } |
861 | ||
3dc7e315 DG |
862 | return entry; |
863 | } | |
864 | ||
f368c07d AG |
865 | /* Find an existing audit rule. |
866 | * Caller must hold audit_filter_mutex to prevent stale rule data. */ | |
867 | static struct audit_entry *audit_find_rule(struct audit_entry *entry, | |
36c4f1b1 | 868 | struct list_head **p) |
f368c07d AG |
869 | { |
870 | struct audit_entry *e, *found = NULL; | |
36c4f1b1 | 871 | struct list_head *list; |
f368c07d AG |
872 | int h; |
873 | ||
36c4f1b1 AV |
874 | if (entry->rule.inode_f) { |
875 | h = audit_hash_ino(entry->rule.inode_f->val); | |
876 | *p = list = &audit_inode_hash[h]; | |
877 | } else if (entry->rule.watch) { | |
f368c07d AG |
878 | /* we don't know the inode number, so must walk entire hash */ |
879 | for (h = 0; h < AUDIT_INODE_BUCKETS; h++) { | |
880 | list = &audit_inode_hash[h]; | |
881 | list_for_each_entry(e, list, list) | |
882 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
883 | found = e; | |
884 | goto out; | |
885 | } | |
886 | } | |
887 | goto out; | |
36c4f1b1 AV |
888 | } else { |
889 | *p = list = &audit_filter_list[entry->rule.listnr]; | |
f368c07d AG |
890 | } |
891 | ||
892 | list_for_each_entry(e, list, list) | |
893 | if (!audit_compare_rule(&entry->rule, &e->rule)) { | |
894 | found = e; | |
895 | goto out; | |
896 | } | |
897 | ||
898 | out: | |
899 | return found; | |
900 | } | |
901 | ||
0590b933 AV |
902 | static u64 prio_low = ~0ULL/2; |
903 | static u64 prio_high = ~0ULL/2 - 1; | |
904 | ||
f368c07d | 905 | /* Add rule to given filterlist if not a duplicate. */ |
36c4f1b1 | 906 | static inline int audit_add_rule(struct audit_entry *entry) |
fe7752ba | 907 | { |
93315ed6 | 908 | struct audit_entry *e; |
f368c07d | 909 | struct audit_watch *watch = entry->rule.watch; |
74c3cbe3 | 910 | struct audit_tree *tree = entry->rule.tree; |
36c4f1b1 | 911 | struct list_head *list; |
ae9d2fb4 | 912 | int err = 0; |
471a5c7c AV |
913 | #ifdef CONFIG_AUDITSYSCALL |
914 | int dont_count = 0; | |
915 | ||
42d5e376 RGB |
916 | /* If any of these, don't count towards total */ |
917 | switch(entry->rule.listnr) { | |
918 | case AUDIT_FILTER_USER: | |
d904ac03 | 919 | case AUDIT_FILTER_EXCLUDE: |
42d5e376 | 920 | case AUDIT_FILTER_FS: |
471a5c7c | 921 | dont_count = 1; |
42d5e376 | 922 | } |
471a5c7c | 923 | #endif |
f368c07d | 924 | |
f368c07d | 925 | mutex_lock(&audit_filter_mutex); |
36c4f1b1 | 926 | e = audit_find_rule(entry, &list); |
f368c07d | 927 | if (e) { |
35fe4d0b | 928 | mutex_unlock(&audit_filter_mutex); |
f368c07d | 929 | err = -EEXIST; |
74c3cbe3 AV |
930 | /* normally audit_add_tree_rule() will free it on failure */ |
931 | if (tree) | |
932 | audit_put_tree(tree); | |
f8259b26 | 933 | return err; |
f368c07d | 934 | } |
fe7752ba | 935 | |
f368c07d AG |
936 | if (watch) { |
937 | /* audit_filter_mutex is dropped and re-taken during this call */ | |
ae7b8f41 | 938 | err = audit_add_watch(&entry->rule, &list); |
f368c07d AG |
939 | if (err) { |
940 | mutex_unlock(&audit_filter_mutex); | |
2f992ee8 CG |
941 | /* |
942 | * normally audit_add_tree_rule() will free it | |
943 | * on failure | |
944 | */ | |
945 | if (tree) | |
946 | audit_put_tree(tree); | |
f8259b26 | 947 | return err; |
f368c07d | 948 | } |
fe7752ba | 949 | } |
74c3cbe3 AV |
950 | if (tree) { |
951 | err = audit_add_tree_rule(&entry->rule); | |
952 | if (err) { | |
953 | mutex_unlock(&audit_filter_mutex); | |
f8259b26 | 954 | return err; |
74c3cbe3 AV |
955 | } |
956 | } | |
fe7752ba | 957 | |
0590b933 AV |
958 | entry->rule.prio = ~0ULL; |
959 | if (entry->rule.listnr == AUDIT_FILTER_EXIT) { | |
960 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) | |
961 | entry->rule.prio = ++prio_high; | |
962 | else | |
963 | entry->rule.prio = --prio_low; | |
964 | } | |
965 | ||
fe7752ba | 966 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
e45aa212 AV |
967 | list_add(&entry->rule.list, |
968 | &audit_rules_list[entry->rule.listnr]); | |
fe7752ba | 969 | list_add_rcu(&entry->list, list); |
6a2bceec | 970 | entry->rule.flags &= ~AUDIT_FILTER_PREPEND; |
fe7752ba | 971 | } else { |
e45aa212 AV |
972 | list_add_tail(&entry->rule.list, |
973 | &audit_rules_list[entry->rule.listnr]); | |
fe7752ba DW |
974 | list_add_tail_rcu(&entry->list, list); |
975 | } | |
471a5c7c AV |
976 | #ifdef CONFIG_AUDITSYSCALL |
977 | if (!dont_count) | |
978 | audit_n_rules++; | |
e54dc243 AG |
979 | |
980 | if (!audit_match_signal(entry)) | |
981 | audit_signals++; | |
471a5c7c | 982 | #endif |
f368c07d | 983 | mutex_unlock(&audit_filter_mutex); |
fe7752ba | 984 | |
f368c07d | 985 | return err; |
fe7752ba DW |
986 | } |
987 | ||
f368c07d | 988 | /* Remove an existing rule from filterlist. */ |
7f492942 | 989 | int audit_del_rule(struct audit_entry *entry) |
fe7752ba DW |
990 | { |
991 | struct audit_entry *e; | |
74c3cbe3 | 992 | struct audit_tree *tree = entry->rule.tree; |
36c4f1b1 | 993 | struct list_head *list; |
36c4f1b1 | 994 | int ret = 0; |
471a5c7c AV |
995 | #ifdef CONFIG_AUDITSYSCALL |
996 | int dont_count = 0; | |
997 | ||
42d5e376 RGB |
998 | /* If any of these, don't count towards total */ |
999 | switch(entry->rule.listnr) { | |
1000 | case AUDIT_FILTER_USER: | |
d904ac03 | 1001 | case AUDIT_FILTER_EXCLUDE: |
42d5e376 | 1002 | case AUDIT_FILTER_FS: |
471a5c7c | 1003 | dont_count = 1; |
42d5e376 | 1004 | } |
471a5c7c | 1005 | #endif |
f368c07d | 1006 | |
f368c07d | 1007 | mutex_lock(&audit_filter_mutex); |
36c4f1b1 | 1008 | e = audit_find_rule(entry, &list); |
f368c07d | 1009 | if (!e) { |
f368c07d AG |
1010 | ret = -ENOENT; |
1011 | goto out; | |
1012 | } | |
1013 | ||
cfcad62c | 1014 | if (e->rule.watch) |
a05fb6cc | 1015 | audit_remove_watch_rule(&e->rule); |
f368c07d | 1016 | |
74c3cbe3 AV |
1017 | if (e->rule.tree) |
1018 | audit_remove_tree_rule(&e->rule); | |
1019 | ||
34d99af5 RGB |
1020 | if (e->rule.exe) |
1021 | audit_remove_mark_rule(&e->rule); | |
1022 | ||
471a5c7c AV |
1023 | #ifdef CONFIG_AUDITSYSCALL |
1024 | if (!dont_count) | |
1025 | audit_n_rules--; | |
e54dc243 AG |
1026 | |
1027 | if (!audit_match_signal(entry)) | |
1028 | audit_signals--; | |
471a5c7c | 1029 | #endif |
8c85fc9a RGB |
1030 | |
1031 | list_del_rcu(&e->list); | |
1032 | list_del(&e->rule.list); | |
1033 | call_rcu(&e->rcu, audit_free_rule_rcu); | |
f368c07d | 1034 | |
f368c07d | 1035 | out: |
8c85fc9a RGB |
1036 | mutex_unlock(&audit_filter_mutex); |
1037 | ||
74c3cbe3 AV |
1038 | if (tree) |
1039 | audit_put_tree(tree); /* that's the temporary one */ | |
f368c07d AG |
1040 | |
1041 | return ret; | |
fe7752ba DW |
1042 | } |
1043 | ||
93315ed6 | 1044 | /* List rules using struct audit_rule_data. */ |
45a0642b | 1045 | static void audit_list_rules(int seq, struct sk_buff_head *q) |
93315ed6 | 1046 | { |
9044e6bc | 1047 | struct sk_buff *skb; |
e45aa212 | 1048 | struct audit_krule *r; |
93315ed6 AG |
1049 | int i; |
1050 | ||
f368c07d AG |
1051 | /* This is a blocking read, so use audit_filter_mutex instead of rcu |
1052 | * iterator to sync with list writers. */ | |
93315ed6 | 1053 | for (i=0; i<AUDIT_NR_FILTERS; i++) { |
e45aa212 | 1054 | list_for_each_entry(r, &audit_rules_list[i], list) { |
f368c07d AG |
1055 | struct audit_rule_data *data; |
1056 | ||
e45aa212 | 1057 | data = audit_krule_to_data(r); |
f368c07d AG |
1058 | if (unlikely(!data)) |
1059 | break; | |
45a0642b PM |
1060 | skb = audit_make_reply(seq, AUDIT_LIST_RULES, 0, 1, |
1061 | data, | |
f9441639 | 1062 | sizeof(*data) + data->buflen); |
9044e6bc AV |
1063 | if (skb) |
1064 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1065 | kfree(data); |
1066 | } | |
1067 | } | |
45a0642b | 1068 | skb = audit_make_reply(seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); |
9044e6bc AV |
1069 | if (skb) |
1070 | skb_queue_tail(q, skb); | |
93315ed6 AG |
1071 | } |
1072 | ||
5adc8a6a | 1073 | /* Log rule additions and removals */ |
dc9eb698 | 1074 | static void audit_log_rule_change(char *action, struct audit_krule *rule, int res) |
5adc8a6a AG |
1075 | { |
1076 | struct audit_buffer *ab; | |
1077 | ||
1a6b9f23 EP |
1078 | if (!audit_enabled) |
1079 | return; | |
1080 | ||
626abcd1 | 1081 | ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
5adc8a6a AG |
1082 | if (!ab) |
1083 | return; | |
5c5b8d8b | 1084 | audit_log_session_info(ab); |
b122c376 | 1085 | audit_log_task_context(ab); |
c1e8f06d | 1086 | audit_log_format(ab, " op=%s", action); |
9d960985 | 1087 | audit_log_key(ab, rule->filterkey); |
5adc8a6a AG |
1088 | audit_log_format(ab, " list=%d res=%d", rule->listnr, res); |
1089 | audit_log_end(ab); | |
1090 | } | |
1091 | ||
fe7752ba | 1092 | /** |
ce0d9f04 | 1093 | * audit_rule_change - apply all rules to the specified message type |
fe7752ba | 1094 | * @type: audit message type |
fe7752ba DW |
1095 | * @seq: netlink audit message sequence (serial) number |
1096 | * @data: payload data | |
93315ed6 | 1097 | * @datasz: size of payload data |
fe7752ba | 1098 | */ |
45a0642b | 1099 | int audit_rule_change(int type, int seq, void *data, size_t datasz) |
fe7752ba | 1100 | { |
93315ed6 AG |
1101 | int err = 0; |
1102 | struct audit_entry *entry; | |
fe7752ba DW |
1103 | |
1104 | switch (type) { | |
93315ed6 | 1105 | case AUDIT_ADD_RULE: |
70c4cf17 WW |
1106 | entry = audit_data_to_entry(data, datasz); |
1107 | if (IS_ERR(entry)) | |
1108 | return PTR_ERR(entry); | |
36c4f1b1 | 1109 | err = audit_add_rule(entry); |
e7df61f4 | 1110 | audit_log_rule_change("add_rule", &entry->rule, !err); |
fe7752ba | 1111 | break; |
93315ed6 | 1112 | case AUDIT_DEL_RULE: |
70c4cf17 WW |
1113 | entry = audit_data_to_entry(data, datasz); |
1114 | if (IS_ERR(entry)) | |
1115 | return PTR_ERR(entry); | |
36c4f1b1 | 1116 | err = audit_del_rule(entry); |
e7df61f4 | 1117 | audit_log_rule_change("remove_rule", &entry->rule, !err); |
fe7752ba DW |
1118 | break; |
1119 | default: | |
739c9503 | 1120 | WARN_ON(1); |
70c4cf17 | 1121 | return -EINVAL; |
fe7752ba DW |
1122 | } |
1123 | ||
34d99af5 RGB |
1124 | if (err || type == AUDIT_DEL_RULE) { |
1125 | if (entry->rule.exe) | |
1126 | audit_remove_mark(entry->rule.exe); | |
e85322d2 | 1127 | audit_free_rule(entry); |
34d99af5 | 1128 | } |
e85322d2 | 1129 | |
fe7752ba DW |
1130 | return err; |
1131 | } | |
1132 | ||
ce0d9f04 RGB |
1133 | /** |
1134 | * audit_list_rules_send - list the audit rules | |
d211f177 | 1135 | * @request_skb: skb of request we are replying to (used to target the reply) |
ce0d9f04 RGB |
1136 | * @seq: netlink audit message sequence (serial) number |
1137 | */ | |
6f285b19 | 1138 | int audit_list_rules_send(struct sk_buff *request_skb, int seq) |
ce0d9f04 | 1139 | { |
6f285b19 EB |
1140 | u32 portid = NETLINK_CB(request_skb).portid; |
1141 | struct net *net = sock_net(NETLINK_CB(request_skb).sk); | |
ce0d9f04 RGB |
1142 | struct task_struct *tsk; |
1143 | struct audit_netlink_list *dest; | |
1144 | int err = 0; | |
1145 | ||
1146 | /* We can't just spew out the rules here because we might fill | |
1147 | * the available socket buffer space and deadlock waiting for | |
1148 | * auditctl to read from it... which isn't ever going to | |
1149 | * happen if we're actually running in the context of auditctl | |
1150 | * trying to _send_ the stuff */ | |
1151 | ||
1152 | dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); | |
1153 | if (!dest) | |
1154 | return -ENOMEM; | |
6f285b19 | 1155 | dest->net = get_net(net); |
ce0d9f04 | 1156 | dest->portid = portid; |
ce0d9f04 RGB |
1157 | skb_queue_head_init(&dest->q); |
1158 | ||
1159 | mutex_lock(&audit_filter_mutex); | |
45a0642b | 1160 | audit_list_rules(seq, &dest->q); |
ce0d9f04 RGB |
1161 | mutex_unlock(&audit_filter_mutex); |
1162 | ||
1163 | tsk = kthread_run(audit_send_list, dest, "audit_send_list"); | |
1164 | if (IS_ERR(tsk)) { | |
1165 | skb_queue_purge(&dest->q); | |
1166 | kfree(dest); | |
1167 | err = PTR_ERR(tsk); | |
1168 | } | |
1169 | ||
1170 | return err; | |
1171 | } | |
1172 | ||
5af75d8d | 1173 | int audit_comparator(u32 left, u32 op, u32 right) |
fe7752ba DW |
1174 | { |
1175 | switch (op) { | |
5af75d8d | 1176 | case Audit_equal: |
fe7752ba | 1177 | return (left == right); |
5af75d8d | 1178 | case Audit_not_equal: |
fe7752ba | 1179 | return (left != right); |
5af75d8d | 1180 | case Audit_lt: |
fe7752ba | 1181 | return (left < right); |
5af75d8d | 1182 | case Audit_le: |
fe7752ba | 1183 | return (left <= right); |
5af75d8d | 1184 | case Audit_gt: |
fe7752ba | 1185 | return (left > right); |
5af75d8d | 1186 | case Audit_ge: |
fe7752ba | 1187 | return (left >= right); |
5af75d8d | 1188 | case Audit_bitmask: |
74f2345b | 1189 | return (left & right); |
5af75d8d | 1190 | case Audit_bittest: |
74f2345b | 1191 | return ((left & right) == right); |
5af75d8d AV |
1192 | default: |
1193 | BUG(); | |
1194 | return 0; | |
fe7752ba DW |
1195 | } |
1196 | } | |
1197 | ||
ca57ec0f EB |
1198 | int audit_uid_comparator(kuid_t left, u32 op, kuid_t right) |
1199 | { | |
1200 | switch (op) { | |
1201 | case Audit_equal: | |
1202 | return uid_eq(left, right); | |
1203 | case Audit_not_equal: | |
1204 | return !uid_eq(left, right); | |
1205 | case Audit_lt: | |
1206 | return uid_lt(left, right); | |
1207 | case Audit_le: | |
1208 | return uid_lte(left, right); | |
1209 | case Audit_gt: | |
1210 | return uid_gt(left, right); | |
1211 | case Audit_ge: | |
1212 | return uid_gte(left, right); | |
1213 | case Audit_bitmask: | |
1214 | case Audit_bittest: | |
1215 | default: | |
1216 | BUG(); | |
1217 | return 0; | |
1218 | } | |
1219 | } | |
1220 | ||
1221 | int audit_gid_comparator(kgid_t left, u32 op, kgid_t right) | |
1222 | { | |
1223 | switch (op) { | |
1224 | case Audit_equal: | |
1225 | return gid_eq(left, right); | |
1226 | case Audit_not_equal: | |
1227 | return !gid_eq(left, right); | |
1228 | case Audit_lt: | |
1229 | return gid_lt(left, right); | |
1230 | case Audit_le: | |
1231 | return gid_lte(left, right); | |
1232 | case Audit_gt: | |
1233 | return gid_gt(left, right); | |
1234 | case Audit_ge: | |
1235 | return gid_gte(left, right); | |
1236 | case Audit_bitmask: | |
1237 | case Audit_bittest: | |
1238 | default: | |
1239 | BUG(); | |
1240 | return 0; | |
1241 | } | |
1242 | } | |
1243 | ||
bfcec708 JL |
1244 | /** |
1245 | * parent_len - find the length of the parent portion of a pathname | |
1246 | * @path: pathname of which to determine length | |
1247 | */ | |
1248 | int parent_len(const char *path) | |
1249 | { | |
1250 | int plen; | |
1251 | const char *p; | |
1252 | ||
1253 | plen = strlen(path); | |
1254 | ||
1255 | if (plen == 0) | |
1256 | return plen; | |
1257 | ||
1258 | /* disregard trailing slashes */ | |
1259 | p = path + plen - 1; | |
1260 | while ((*p == '/') && (p > path)) | |
1261 | p--; | |
1262 | ||
1263 | /* walk backward until we find the next slash or hit beginning */ | |
1264 | while ((*p != '/') && (p > path)) | |
1265 | p--; | |
1266 | ||
1267 | /* did we find a slash? Then increment to include it in path */ | |
1268 | if (*p == '/') | |
1269 | p++; | |
1270 | ||
1271 | return p - path; | |
1272 | } | |
1273 | ||
e3d6b07b JL |
1274 | /** |
1275 | * audit_compare_dname_path - compare given dentry name with last component in | |
1276 | * given path. Return of 0 indicates a match. | |
1277 | * @dname: dentry name that we're comparing | |
1278 | * @path: full pathname that we're comparing | |
1279 | * @parentlen: length of the parent if known. Passing in AUDIT_NAME_FULL | |
1280 | * here indicates that we must compute this value. | |
1281 | */ | |
795d673a | 1282 | int audit_compare_dname_path(const struct qstr *dname, const char *path, int parentlen) |
f368c07d | 1283 | { |
e3d6b07b | 1284 | int dlen, pathlen; |
f368c07d AG |
1285 | const char *p; |
1286 | ||
795d673a | 1287 | dlen = dname->len; |
29e9a346 EP |
1288 | pathlen = strlen(path); |
1289 | if (pathlen < dlen) | |
f368c07d AG |
1290 | return 1; |
1291 | ||
e3d6b07b | 1292 | parentlen = parentlen == AUDIT_NAME_FULL ? parent_len(path) : parentlen; |
29e9a346 | 1293 | if (pathlen - parentlen != dlen) |
f368c07d | 1294 | return 1; |
29e9a346 EP |
1295 | |
1296 | p = path + parentlen; | |
fe7752ba | 1297 | |
795d673a | 1298 | return strncmp(p, dname->name, dlen); |
f368c07d | 1299 | } |
fe7752ba | 1300 | |
86b2efbe | 1301 | int audit_filter(int msgtype, unsigned int listtype) |
fe7752ba DW |
1302 | { |
1303 | struct audit_entry *e; | |
86b2efbe | 1304 | int ret = 1; /* Audit by default */ |
9ce34218 | 1305 | |
fe7752ba | 1306 | rcu_read_lock(); |
86b2efbe RGB |
1307 | list_for_each_entry_rcu(e, &audit_filter_list[listtype], list) { |
1308 | int i, result = 0; | |
fe7752ba | 1309 | |
93315ed6 AG |
1310 | for (i = 0; i < e->rule.field_count; i++) { |
1311 | struct audit_field *f = &e->rule.fields[i]; | |
86b2efbe RGB |
1312 | pid_t pid; |
1313 | u32 sid; | |
1314 | ||
1315 | switch (f->type) { | |
1316 | case AUDIT_PID: | |
1317 | pid = task_pid_nr(current); | |
1318 | result = audit_comparator(pid, f->op, f->val); | |
1319 | break; | |
1320 | case AUDIT_UID: | |
1321 | result = audit_uid_comparator(current_uid(), f->op, f->uid); | |
1322 | break; | |
1323 | case AUDIT_GID: | |
1324 | result = audit_gid_comparator(current_gid(), f->op, f->gid); | |
1325 | break; | |
1326 | case AUDIT_LOGINUID: | |
1327 | result = audit_uid_comparator(audit_get_loginuid(current), | |
1328 | f->op, f->uid); | |
1329 | break; | |
1330 | case AUDIT_LOGINUID_SET: | |
1331 | result = audit_comparator(audit_loginuid_set(current), | |
1332 | f->op, f->val); | |
1333 | break; | |
1334 | case AUDIT_MSGTYPE: | |
1335 | result = audit_comparator(msgtype, f->op, f->val); | |
1336 | break; | |
1337 | case AUDIT_SUBJ_USER: | |
1338 | case AUDIT_SUBJ_ROLE: | |
1339 | case AUDIT_SUBJ_TYPE: | |
1340 | case AUDIT_SUBJ_SEN: | |
1341 | case AUDIT_SUBJ_CLR: | |
1342 | if (f->lsm_rule) { | |
1343 | security_task_getsecid(current, &sid); | |
1344 | result = security_audit_rule_match(sid, | |
90462a5b | 1345 | f->type, f->op, f->lsm_rule); |
86b2efbe RGB |
1346 | } |
1347 | break; | |
29c1372d OM |
1348 | case AUDIT_EXE: |
1349 | result = audit_exe_compare(current, e->rule.exe); | |
1350 | if (f->op == Audit_not_equal) | |
1351 | result = !result; | |
1352 | break; | |
86b2efbe RGB |
1353 | default: |
1354 | goto unlock_and_return; | |
fe7752ba | 1355 | } |
86b2efbe RGB |
1356 | if (result < 0) /* error */ |
1357 | goto unlock_and_return; | |
1358 | if (!result) | |
1359 | break; | |
1360 | } | |
1361 | if (result > 0) { | |
d904ac03 | 1362 | if (e->rule.action == AUDIT_NEVER || listtype == AUDIT_FILTER_EXCLUDE) |
86b2efbe RGB |
1363 | ret = 0; |
1364 | break; | |
fe7752ba | 1365 | } |
fe7752ba DW |
1366 | } |
1367 | unlock_and_return: | |
1368 | rcu_read_unlock(); | |
86b2efbe | 1369 | return ret; |
fe7752ba | 1370 | } |
3dc7e315 | 1371 | |
e45aa212 | 1372 | static int update_lsm_rule(struct audit_krule *r) |
1a9d0797 | 1373 | { |
e45aa212 | 1374 | struct audit_entry *entry = container_of(r, struct audit_entry, rule); |
1a9d0797 | 1375 | struct audit_entry *nentry; |
1a9d0797 AV |
1376 | int err = 0; |
1377 | ||
e45aa212 | 1378 | if (!security_audit_rule_known(r)) |
1a9d0797 AV |
1379 | return 0; |
1380 | ||
ae7b8f41 | 1381 | nentry = audit_dupe_rule(r); |
34d99af5 RGB |
1382 | if (entry->rule.exe) |
1383 | audit_remove_mark(entry->rule.exe); | |
1a9d0797 AV |
1384 | if (IS_ERR(nentry)) { |
1385 | /* save the first error encountered for the | |
1386 | * return value */ | |
1387 | err = PTR_ERR(nentry); | |
1388 | audit_panic("error updating LSM filters"); | |
ae7b8f41 | 1389 | if (r->watch) |
e45aa212 | 1390 | list_del(&r->rlist); |
1a9d0797 | 1391 | list_del_rcu(&entry->list); |
e45aa212 | 1392 | list_del(&r->list); |
1a9d0797 | 1393 | } else { |
ae7b8f41 | 1394 | if (r->watch || r->tree) |
e45aa212 | 1395 | list_replace_init(&r->rlist, &nentry->rule.rlist); |
1a9d0797 | 1396 | list_replace_rcu(&entry->list, &nentry->list); |
e45aa212 | 1397 | list_replace(&r->list, &nentry->rule.list); |
1a9d0797 AV |
1398 | } |
1399 | call_rcu(&entry->rcu, audit_free_rule_rcu); | |
1400 | ||
1401 | return err; | |
1402 | } | |
1403 | ||
04305e4a | 1404 | /* This function will re-initialize the lsm_rule field of all applicable rules. |
d7a96f3a | 1405 | * It will traverse the filter lists serarching for rules that contain LSM |
3dc7e315 | 1406 | * specific filter fields. When such a rule is found, it is copied, the |
d7a96f3a | 1407 | * LSM field is re-initialized, and the old rule is replaced with the |
3dc7e315 | 1408 | * updated rule. */ |
d7a96f3a | 1409 | int audit_update_lsm_rules(void) |
3dc7e315 | 1410 | { |
e45aa212 | 1411 | struct audit_krule *r, *n; |
3dc7e315 DG |
1412 | int i, err = 0; |
1413 | ||
f368c07d AG |
1414 | /* audit_filter_mutex synchronizes the writers */ |
1415 | mutex_lock(&audit_filter_mutex); | |
3dc7e315 DG |
1416 | |
1417 | for (i = 0; i < AUDIT_NR_FILTERS; i++) { | |
e45aa212 AV |
1418 | list_for_each_entry_safe(r, n, &audit_rules_list[i], list) { |
1419 | int res = update_lsm_rule(r); | |
1a9d0797 AV |
1420 | if (!err) |
1421 | err = res; | |
3dc7e315 DG |
1422 | } |
1423 | } | |
f368c07d | 1424 | mutex_unlock(&audit_filter_mutex); |
3dc7e315 DG |
1425 | |
1426 | return err; | |
1427 | } |