Commit | Line | Data |
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85c8721f | 1 | /* auditsc.c -- System-call auditing support |
1da177e4 LT |
2 | * Handles all system-call specific auditing features. |
3 | * | |
4 | * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina. | |
73241ccc | 5 | * Copyright 2005 Hewlett-Packard Development Company, L.P. |
b63862f4 | 6 | * Copyright (C) 2005 IBM Corporation |
1da177e4 LT |
7 | * All Rights Reserved. |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation; either version 2 of the License, or | |
12 | * (at your option) any later version. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | * | |
19 | * You should have received a copy of the GNU General Public License | |
20 | * along with this program; if not, write to the Free Software | |
21 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
22 | * | |
23 | * Written by Rickard E. (Rik) Faith <faith@redhat.com> | |
24 | * | |
25 | * Many of the ideas implemented here are from Stephen C. Tweedie, | |
26 | * especially the idea of avoiding a copy by using getname. | |
27 | * | |
28 | * The method for actual interception of syscall entry and exit (not in | |
29 | * this file -- see entry.S) is based on a GPL'd patch written by | |
30 | * okir@suse.de and Copyright 2003 SuSE Linux AG. | |
31 | * | |
b63862f4 DK |
32 | * The support of additional filter rules compares (>, <, >=, <=) was |
33 | * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005. | |
34 | * | |
73241ccc AG |
35 | * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional |
36 | * filesystem information. | |
1da177e4 LT |
37 | */ |
38 | ||
39 | #include <linux/init.h> | |
1da177e4 | 40 | #include <asm/types.h> |
715b49ef | 41 | #include <asm/atomic.h> |
73241ccc AG |
42 | #include <asm/types.h> |
43 | #include <linux/fs.h> | |
44 | #include <linux/namei.h> | |
1da177e4 LT |
45 | #include <linux/mm.h> |
46 | #include <linux/module.h> | |
01116105 | 47 | #include <linux/mount.h> |
3ec3b2fb | 48 | #include <linux/socket.h> |
1da177e4 LT |
49 | #include <linux/audit.h> |
50 | #include <linux/personality.h> | |
51 | #include <linux/time.h> | |
f6a789d1 | 52 | #include <linux/kthread.h> |
5bb289b5 | 53 | #include <linux/netlink.h> |
f5561964 | 54 | #include <linux/compiler.h> |
1da177e4 LT |
55 | #include <asm/unistd.h> |
56 | ||
57 | /* 0 = no checking | |
58 | 1 = put_count checking | |
59 | 2 = verbose put_count checking | |
60 | */ | |
61 | #define AUDIT_DEBUG 0 | |
62 | ||
63 | /* No syscall auditing will take place unless audit_enabled != 0. */ | |
64 | extern int audit_enabled; | |
65 | ||
66 | /* AUDIT_NAMES is the number of slots we reserve in the audit_context | |
67 | * for saving names from getname(). */ | |
68 | #define AUDIT_NAMES 20 | |
69 | ||
70 | /* AUDIT_NAMES_RESERVED is the number of slots we reserve in the | |
71 | * audit_context from being used for nameless inodes from | |
72 | * path_lookup. */ | |
73 | #define AUDIT_NAMES_RESERVED 7 | |
74 | ||
75 | /* At task start time, the audit_state is set in the audit_context using | |
76 | a per-task filter. At syscall entry, the audit_state is augmented by | |
77 | the syscall filter. */ | |
78 | enum audit_state { | |
79 | AUDIT_DISABLED, /* Do not create per-task audit_context. | |
80 | * No syscall-specific audit records can | |
81 | * be generated. */ | |
82 | AUDIT_SETUP_CONTEXT, /* Create the per-task audit_context, | |
83 | * but don't necessarily fill it in at | |
84 | * syscall entry time (i.e., filter | |
85 | * instead). */ | |
86 | AUDIT_BUILD_CONTEXT, /* Create the per-task audit_context, | |
87 | * and always fill it in at syscall | |
88 | * entry time. This makes a full | |
89 | * syscall record available if some | |
90 | * other part of the kernel decides it | |
91 | * should be recorded. */ | |
92 | AUDIT_RECORD_CONTEXT /* Create the per-task audit_context, | |
93 | * always fill it in at syscall entry | |
94 | * time, and always write out the audit | |
95 | * record at syscall exit time. */ | |
96 | }; | |
97 | ||
98 | /* When fs/namei.c:getname() is called, we store the pointer in name and | |
99 | * we don't let putname() free it (instead we free all of the saved | |
100 | * pointers at syscall exit time). | |
101 | * | |
102 | * Further, in fs/namei.c:path_lookup() we store the inode and device. */ | |
103 | struct audit_names { | |
104 | const char *name; | |
105 | unsigned long ino; | |
73241ccc | 106 | unsigned long pino; |
1da177e4 LT |
107 | dev_t dev; |
108 | umode_t mode; | |
109 | uid_t uid; | |
110 | gid_t gid; | |
111 | dev_t rdev; | |
112 | }; | |
113 | ||
114 | struct audit_aux_data { | |
115 | struct audit_aux_data *next; | |
116 | int type; | |
117 | }; | |
118 | ||
119 | #define AUDIT_AUX_IPCPERM 0 | |
120 | ||
121 | struct audit_aux_data_ipcctl { | |
122 | struct audit_aux_data d; | |
123 | struct ipc_perm p; | |
124 | unsigned long qbytes; | |
125 | uid_t uid; | |
126 | gid_t gid; | |
127 | mode_t mode; | |
128 | }; | |
129 | ||
3ec3b2fb DW |
130 | struct audit_aux_data_socketcall { |
131 | struct audit_aux_data d; | |
132 | int nargs; | |
133 | unsigned long args[0]; | |
134 | }; | |
135 | ||
136 | struct audit_aux_data_sockaddr { | |
137 | struct audit_aux_data d; | |
138 | int len; | |
139 | char a[0]; | |
140 | }; | |
141 | ||
01116105 SS |
142 | struct audit_aux_data_path { |
143 | struct audit_aux_data d; | |
144 | struct dentry *dentry; | |
145 | struct vfsmount *mnt; | |
146 | }; | |
1da177e4 LT |
147 | |
148 | /* The per-task audit context. */ | |
149 | struct audit_context { | |
150 | int in_syscall; /* 1 if task is in a syscall */ | |
151 | enum audit_state state; | |
152 | unsigned int serial; /* serial number for record */ | |
153 | struct timespec ctime; /* time of syscall entry */ | |
154 | uid_t loginuid; /* login uid (identity) */ | |
155 | int major; /* syscall number */ | |
156 | unsigned long argv[4]; /* syscall arguments */ | |
157 | int return_valid; /* return code is valid */ | |
2fd6f58b | 158 | long return_code;/* syscall return code */ |
1da177e4 LT |
159 | int auditable; /* 1 if record should be written */ |
160 | int name_count; | |
161 | struct audit_names names[AUDIT_NAMES]; | |
8f37d47c DW |
162 | struct dentry * pwd; |
163 | struct vfsmount * pwdmnt; | |
1da177e4 LT |
164 | struct audit_context *previous; /* For nested syscalls */ |
165 | struct audit_aux_data *aux; | |
166 | ||
167 | /* Save things to print about task_struct */ | |
168 | pid_t pid; | |
169 | uid_t uid, euid, suid, fsuid; | |
170 | gid_t gid, egid, sgid, fsgid; | |
171 | unsigned long personality; | |
2fd6f58b | 172 | int arch; |
1da177e4 LT |
173 | |
174 | #if AUDIT_DEBUG | |
175 | int put_count; | |
176 | int ino_count; | |
177 | #endif | |
178 | }; | |
179 | ||
180 | /* Public API */ | |
181 | /* There are three lists of rules -- one to search at task creation | |
182 | * time, one to search at syscall entry time, and another to search at | |
183 | * syscall exit time. */ | |
0f45aa18 DW |
184 | static struct list_head audit_filter_list[AUDIT_NR_FILTERS] = { |
185 | LIST_HEAD_INIT(audit_filter_list[0]), | |
186 | LIST_HEAD_INIT(audit_filter_list[1]), | |
187 | LIST_HEAD_INIT(audit_filter_list[2]), | |
188 | LIST_HEAD_INIT(audit_filter_list[3]), | |
189 | LIST_HEAD_INIT(audit_filter_list[4]), | |
c8edc80c DK |
190 | LIST_HEAD_INIT(audit_filter_list[5]), |
191 | #if AUDIT_NR_FILTERS != 6 | |
0f45aa18 DW |
192 | #error Fix audit_filter_list initialiser |
193 | #endif | |
194 | }; | |
1da177e4 LT |
195 | |
196 | struct audit_entry { | |
197 | struct list_head list; | |
198 | struct rcu_head rcu; | |
199 | struct audit_rule rule; | |
200 | }; | |
201 | ||
7ca00264 DW |
202 | extern int audit_pid; |
203 | ||
3c789a19 AG |
204 | /* Copy rule from user-space to kernel-space. Called from |
205 | * audit_add_rule during AUDIT_ADD. */ | |
206 | static inline int audit_copy_rule(struct audit_rule *d, struct audit_rule *s) | |
207 | { | |
208 | int i; | |
209 | ||
210 | if (s->action != AUDIT_NEVER | |
211 | && s->action != AUDIT_POSSIBLE | |
212 | && s->action != AUDIT_ALWAYS) | |
213 | return -1; | |
214 | if (s->field_count < 0 || s->field_count > AUDIT_MAX_FIELDS) | |
215 | return -1; | |
216 | if ((s->flags & ~AUDIT_FILTER_PREPEND) >= AUDIT_NR_FILTERS) | |
217 | return -1; | |
218 | ||
219 | d->flags = s->flags; | |
220 | d->action = s->action; | |
221 | d->field_count = s->field_count; | |
222 | for (i = 0; i < d->field_count; i++) { | |
223 | d->fields[i] = s->fields[i]; | |
224 | d->values[i] = s->values[i]; | |
225 | } | |
226 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) d->mask[i] = s->mask[i]; | |
227 | return 0; | |
228 | } | |
229 | ||
1da177e4 | 230 | /* Check to see if two rules are identical. It is called from |
3c789a19 | 231 | * audit_add_rule during AUDIT_ADD and |
1da177e4 | 232 | * audit_del_rule during AUDIT_DEL. */ |
3c789a19 | 233 | static inline int audit_compare_rule(struct audit_rule *a, struct audit_rule *b) |
1da177e4 LT |
234 | { |
235 | int i; | |
236 | ||
237 | if (a->flags != b->flags) | |
238 | return 1; | |
239 | ||
240 | if (a->action != b->action) | |
241 | return 1; | |
242 | ||
243 | if (a->field_count != b->field_count) | |
244 | return 1; | |
245 | ||
246 | for (i = 0; i < a->field_count; i++) { | |
247 | if (a->fields[i] != b->fields[i] | |
248 | || a->values[i] != b->values[i]) | |
249 | return 1; | |
250 | } | |
251 | ||
252 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++) | |
253 | if (a->mask[i] != b->mask[i]) | |
254 | return 1; | |
255 | ||
256 | return 0; | |
257 | } | |
258 | ||
259 | /* Note that audit_add_rule and audit_del_rule are called via | |
260 | * audit_receive() in audit.c, and are protected by | |
261 | * audit_netlink_sem. */ | |
3c789a19 | 262 | static inline int audit_add_rule(struct audit_rule *rule, |
0f45aa18 | 263 | struct list_head *list) |
1da177e4 | 264 | { |
3c789a19 | 265 | struct audit_entry *entry; |
b63862f4 | 266 | int i; |
3c789a19 AG |
267 | |
268 | /* Do not use the _rcu iterator here, since this is the only | |
269 | * addition routine. */ | |
270 | list_for_each_entry(entry, list, list) { | |
271 | if (!audit_compare_rule(rule, &entry->rule)) { | |
272 | return -EEXIST; | |
273 | } | |
274 | } | |
275 | ||
b63862f4 DK |
276 | for (i = 0; i < rule->field_count; i++) { |
277 | if (rule->fields[i] & AUDIT_UNUSED_BITS) | |
278 | return -EINVAL; | |
279 | if ( rule->fields[i] & AUDIT_NEGATE ) | |
280 | rule->fields[i] |= AUDIT_NOT_EQUAL; | |
281 | else if ( (rule->fields[i] & AUDIT_OPERATORS) == 0 ) | |
282 | rule->fields[i] |= AUDIT_EQUAL; | |
283 | rule->fields[i] &= (~AUDIT_NEGATE); | |
284 | } | |
285 | ||
3c789a19 AG |
286 | if (!(entry = kmalloc(sizeof(*entry), GFP_KERNEL))) |
287 | return -ENOMEM; | |
288 | if (audit_copy_rule(&entry->rule, rule)) { | |
289 | kfree(entry); | |
290 | return -EINVAL; | |
291 | } | |
292 | ||
0f45aa18 DW |
293 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
294 | entry->rule.flags &= ~AUDIT_FILTER_PREPEND; | |
1da177e4 LT |
295 | list_add_rcu(&entry->list, list); |
296 | } else { | |
297 | list_add_tail_rcu(&entry->list, list); | |
298 | } | |
3c789a19 AG |
299 | |
300 | return 0; | |
1da177e4 LT |
301 | } |
302 | ||
3c789a19 | 303 | static inline void audit_free_rule(struct rcu_head *head) |
1da177e4 LT |
304 | { |
305 | struct audit_entry *e = container_of(head, struct audit_entry, rcu); | |
306 | kfree(e); | |
307 | } | |
308 | ||
309 | /* Note that audit_add_rule and audit_del_rule are called via | |
310 | * audit_receive() in audit.c, and are protected by | |
311 | * audit_netlink_sem. */ | |
312 | static inline int audit_del_rule(struct audit_rule *rule, | |
313 | struct list_head *list) | |
314 | { | |
315 | struct audit_entry *e; | |
316 | ||
317 | /* Do not use the _rcu iterator here, since this is the only | |
318 | * deletion routine. */ | |
319 | list_for_each_entry(e, list, list) { | |
320 | if (!audit_compare_rule(rule, &e->rule)) { | |
321 | list_del_rcu(&e->list); | |
322 | call_rcu(&e->rcu, audit_free_rule); | |
323 | return 0; | |
324 | } | |
325 | } | |
0f45aa18 | 326 | return -ENOENT; /* No matching rule */ |
1da177e4 LT |
327 | } |
328 | ||
f6a789d1 DW |
329 | static int audit_list_rules(void *_dest) |
330 | { | |
331 | int pid, seq; | |
332 | int *dest = _dest; | |
333 | struct audit_entry *entry; | |
334 | int i; | |
335 | ||
336 | pid = dest[0]; | |
337 | seq = dest[1]; | |
338 | kfree(dest); | |
339 | ||
340 | down(&audit_netlink_sem); | |
341 | ||
342 | /* The *_rcu iterators not needed here because we are | |
343 | always called with audit_netlink_sem held. */ | |
344 | for (i=0; i<AUDIT_NR_FILTERS; i++) { | |
345 | list_for_each_entry(entry, &audit_filter_list[i], list) | |
346 | audit_send_reply(pid, seq, AUDIT_LIST, 0, 1, | |
347 | &entry->rule, sizeof(entry->rule)); | |
348 | } | |
349 | audit_send_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0); | |
350 | ||
351 | up(&audit_netlink_sem); | |
352 | return 0; | |
353 | } | |
354 | ||
b0dd25a8 RD |
355 | /** |
356 | * audit_receive_filter - apply all rules to the specified message type | |
357 | * @type: audit message type | |
358 | * @pid: target pid for netlink audit messages | |
359 | * @uid: target uid for netlink audit messages | |
360 | * @seq: netlink audit message sequence (serial) number | |
361 | * @data: payload data | |
362 | * @loginuid: loginuid of sender | |
363 | */ | |
c94c257c SH |
364 | int audit_receive_filter(int type, int pid, int uid, int seq, void *data, |
365 | uid_t loginuid) | |
1da177e4 | 366 | { |
f6a789d1 DW |
367 | struct task_struct *tsk; |
368 | int *dest; | |
1da177e4 | 369 | int err = 0; |
0f45aa18 | 370 | unsigned listnr; |
1da177e4 LT |
371 | |
372 | switch (type) { | |
373 | case AUDIT_LIST: | |
f6a789d1 DW |
374 | /* We can't just spew out the rules here because we might fill |
375 | * the available socket buffer space and deadlock waiting for | |
376 | * auditctl to read from it... which isn't ever going to | |
377 | * happen if we're actually running in the context of auditctl | |
378 | * trying to _send_ the stuff */ | |
379 | ||
380 | dest = kmalloc(2 * sizeof(int), GFP_KERNEL); | |
381 | if (!dest) | |
382 | return -ENOMEM; | |
383 | dest[0] = pid; | |
384 | dest[1] = seq; | |
385 | ||
386 | tsk = kthread_run(audit_list_rules, dest, "audit_list_rules"); | |
387 | if (IS_ERR(tsk)) { | |
388 | kfree(dest); | |
389 | err = PTR_ERR(tsk); | |
0f45aa18 | 390 | } |
1da177e4 LT |
391 | break; |
392 | case AUDIT_ADD: | |
3c789a19 AG |
393 | listnr =((struct audit_rule *)data)->flags & ~AUDIT_FILTER_PREPEND; |
394 | if (listnr >= AUDIT_NR_FILTERS) | |
1da177e4 | 395 | return -EINVAL; |
3c789a19 AG |
396 | |
397 | err = audit_add_rule(data, &audit_filter_list[listnr]); | |
398 | if (!err) | |
399 | audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, | |
400 | "auid=%u added an audit rule\n", loginuid); | |
1da177e4 LT |
401 | break; |
402 | case AUDIT_DEL: | |
0f45aa18 DW |
403 | listnr =((struct audit_rule *)data)->flags & ~AUDIT_FILTER_PREPEND; |
404 | if (listnr >= AUDIT_NR_FILTERS) | |
405 | return -EINVAL; | |
406 | ||
407 | err = audit_del_rule(data, &audit_filter_list[listnr]); | |
408 | if (!err) | |
9ad9ad38 | 409 | audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, |
0f45aa18 | 410 | "auid=%u removed an audit rule\n", loginuid); |
1da177e4 LT |
411 | break; |
412 | default: | |
413 | return -EINVAL; | |
414 | } | |
415 | ||
416 | return err; | |
417 | } | |
1da177e4 | 418 | |
b63862f4 DK |
419 | static int audit_comparator(const u32 left, const u32 op, const u32 right) |
420 | { | |
421 | switch (op) { | |
422 | case AUDIT_EQUAL: | |
423 | return (left == right); | |
424 | case AUDIT_NOT_EQUAL: | |
425 | return (left != right); | |
426 | case AUDIT_LESS_THAN: | |
427 | return (left < right); | |
428 | case AUDIT_LESS_THAN_OR_EQUAL: | |
429 | return (left <= right); | |
430 | case AUDIT_GREATER_THAN: | |
431 | return (left > right); | |
432 | case AUDIT_GREATER_THAN_OR_EQUAL: | |
433 | return (left >= right); | |
434 | default: | |
435 | return -EINVAL; | |
436 | } | |
437 | } | |
438 | ||
1da177e4 LT |
439 | /* Compare a task_struct with an audit_rule. Return 1 on match, 0 |
440 | * otherwise. */ | |
441 | static int audit_filter_rules(struct task_struct *tsk, | |
442 | struct audit_rule *rule, | |
443 | struct audit_context *ctx, | |
444 | enum audit_state *state) | |
445 | { | |
446 | int i, j; | |
447 | ||
448 | for (i = 0; i < rule->field_count; i++) { | |
b63862f4 DK |
449 | u32 field = rule->fields[i] & ~AUDIT_OPERATORS; |
450 | u32 op = rule->fields[i] & AUDIT_OPERATORS; | |
1da177e4 LT |
451 | u32 value = rule->values[i]; |
452 | int result = 0; | |
453 | ||
454 | switch (field) { | |
455 | case AUDIT_PID: | |
b63862f4 | 456 | result = audit_comparator(tsk->pid, op, value); |
1da177e4 LT |
457 | break; |
458 | case AUDIT_UID: | |
b63862f4 | 459 | result = audit_comparator(tsk->uid, op, value); |
1da177e4 LT |
460 | break; |
461 | case AUDIT_EUID: | |
b63862f4 | 462 | result = audit_comparator(tsk->euid, op, value); |
1da177e4 LT |
463 | break; |
464 | case AUDIT_SUID: | |
b63862f4 | 465 | result = audit_comparator(tsk->suid, op, value); |
1da177e4 LT |
466 | break; |
467 | case AUDIT_FSUID: | |
b63862f4 | 468 | result = audit_comparator(tsk->fsuid, op, value); |
1da177e4 LT |
469 | break; |
470 | case AUDIT_GID: | |
b63862f4 | 471 | result = audit_comparator(tsk->gid, op, value); |
1da177e4 LT |
472 | break; |
473 | case AUDIT_EGID: | |
b63862f4 | 474 | result = audit_comparator(tsk->egid, op, value); |
1da177e4 LT |
475 | break; |
476 | case AUDIT_SGID: | |
b63862f4 | 477 | result = audit_comparator(tsk->sgid, op, value); |
1da177e4 LT |
478 | break; |
479 | case AUDIT_FSGID: | |
b63862f4 | 480 | result = audit_comparator(tsk->fsgid, op, value); |
1da177e4 LT |
481 | break; |
482 | case AUDIT_PERS: | |
b63862f4 | 483 | result = audit_comparator(tsk->personality, op, value); |
1da177e4 | 484 | break; |
2fd6f58b | 485 | case AUDIT_ARCH: |
b63862f4 DK |
486 | if (ctx) |
487 | result = audit_comparator(ctx->arch, op, value); | |
2fd6f58b | 488 | break; |
1da177e4 LT |
489 | |
490 | case AUDIT_EXIT: | |
491 | if (ctx && ctx->return_valid) | |
b63862f4 | 492 | result = audit_comparator(ctx->return_code, op, value); |
1da177e4 LT |
493 | break; |
494 | case AUDIT_SUCCESS: | |
b01f2cc1 DW |
495 | if (ctx && ctx->return_valid) { |
496 | if (value) | |
b63862f4 | 497 | result = audit_comparator(ctx->return_valid, op, AUDITSC_SUCCESS); |
b01f2cc1 | 498 | else |
b63862f4 | 499 | result = audit_comparator(ctx->return_valid, op, AUDITSC_FAILURE); |
b01f2cc1 | 500 | } |
1da177e4 LT |
501 | break; |
502 | case AUDIT_DEVMAJOR: | |
503 | if (ctx) { | |
504 | for (j = 0; j < ctx->name_count; j++) { | |
b63862f4 | 505 | if (audit_comparator(MAJOR(ctx->names[j].dev), op, value)) { |
1da177e4 LT |
506 | ++result; |
507 | break; | |
508 | } | |
509 | } | |
510 | } | |
511 | break; | |
512 | case AUDIT_DEVMINOR: | |
513 | if (ctx) { | |
514 | for (j = 0; j < ctx->name_count; j++) { | |
b63862f4 | 515 | if (audit_comparator(MINOR(ctx->names[j].dev), op, value)) { |
1da177e4 LT |
516 | ++result; |
517 | break; | |
518 | } | |
519 | } | |
520 | } | |
521 | break; | |
522 | case AUDIT_INODE: | |
523 | if (ctx) { | |
524 | for (j = 0; j < ctx->name_count; j++) { | |
73241ccc AG |
525 | if (audit_comparator(ctx->names[j].ino, op, value) || |
526 | audit_comparator(ctx->names[j].pino, op, value)) { | |
1da177e4 LT |
527 | ++result; |
528 | break; | |
529 | } | |
530 | } | |
531 | } | |
532 | break; | |
533 | case AUDIT_LOGINUID: | |
534 | result = 0; | |
535 | if (ctx) | |
b63862f4 | 536 | result = audit_comparator(ctx->loginuid, op, value); |
1da177e4 LT |
537 | break; |
538 | case AUDIT_ARG0: | |
539 | case AUDIT_ARG1: | |
540 | case AUDIT_ARG2: | |
541 | case AUDIT_ARG3: | |
542 | if (ctx) | |
b63862f4 | 543 | result = audit_comparator(ctx->argv[field-AUDIT_ARG0], op, value); |
1da177e4 LT |
544 | break; |
545 | } | |
546 | ||
1da177e4 LT |
547 | if (!result) |
548 | return 0; | |
549 | } | |
550 | switch (rule->action) { | |
551 | case AUDIT_NEVER: *state = AUDIT_DISABLED; break; | |
552 | case AUDIT_POSSIBLE: *state = AUDIT_BUILD_CONTEXT; break; | |
553 | case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; | |
554 | } | |
555 | return 1; | |
556 | } | |
557 | ||
558 | /* At process creation time, we can determine if system-call auditing is | |
559 | * completely disabled for this task. Since we only have the task | |
560 | * structure at this point, we can only check uid and gid. | |
561 | */ | |
562 | static enum audit_state audit_filter_task(struct task_struct *tsk) | |
563 | { | |
564 | struct audit_entry *e; | |
565 | enum audit_state state; | |
566 | ||
567 | rcu_read_lock(); | |
0f45aa18 | 568 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { |
1da177e4 LT |
569 | if (audit_filter_rules(tsk, &e->rule, NULL, &state)) { |
570 | rcu_read_unlock(); | |
571 | return state; | |
572 | } | |
573 | } | |
574 | rcu_read_unlock(); | |
575 | return AUDIT_BUILD_CONTEXT; | |
576 | } | |
577 | ||
578 | /* At syscall entry and exit time, this filter is called if the | |
579 | * audit_state is not low enough that auditing cannot take place, but is | |
23f32d18 | 580 | * also not high enough that we already know we have to write an audit |
b0dd25a8 | 581 | * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). |
1da177e4 LT |
582 | */ |
583 | static enum audit_state audit_filter_syscall(struct task_struct *tsk, | |
584 | struct audit_context *ctx, | |
585 | struct list_head *list) | |
586 | { | |
587 | struct audit_entry *e; | |
c3896495 | 588 | enum audit_state state; |
1da177e4 | 589 | |
351bb722 | 590 | if (audit_pid && tsk->tgid == audit_pid) |
f7056d64 DW |
591 | return AUDIT_DISABLED; |
592 | ||
1da177e4 | 593 | rcu_read_lock(); |
c3896495 | 594 | if (!list_empty(list)) { |
b63862f4 DK |
595 | int word = AUDIT_WORD(ctx->major); |
596 | int bit = AUDIT_BIT(ctx->major); | |
597 | ||
598 | list_for_each_entry_rcu(e, list, list) { | |
599 | if ((e->rule.mask[word] & bit) == bit | |
600 | && audit_filter_rules(tsk, &e->rule, ctx, &state)) { | |
601 | rcu_read_unlock(); | |
602 | return state; | |
603 | } | |
604 | } | |
1da177e4 LT |
605 | } |
606 | rcu_read_unlock(); | |
607 | return AUDIT_BUILD_CONTEXT; | |
608 | } | |
609 | ||
5bb289b5 | 610 | static int audit_filter_user_rules(struct netlink_skb_parms *cb, |
b63862f4 DK |
611 | struct audit_rule *rule, |
612 | enum audit_state *state) | |
5bb289b5 DW |
613 | { |
614 | int i; | |
615 | ||
616 | for (i = 0; i < rule->field_count; i++) { | |
b63862f4 DK |
617 | u32 field = rule->fields[i] & ~AUDIT_OPERATORS; |
618 | u32 op = rule->fields[i] & AUDIT_OPERATORS; | |
5bb289b5 DW |
619 | u32 value = rule->values[i]; |
620 | int result = 0; | |
621 | ||
622 | switch (field) { | |
623 | case AUDIT_PID: | |
b63862f4 | 624 | result = audit_comparator(cb->creds.pid, op, value); |
5bb289b5 DW |
625 | break; |
626 | case AUDIT_UID: | |
b63862f4 | 627 | result = audit_comparator(cb->creds.uid, op, value); |
5bb289b5 DW |
628 | break; |
629 | case AUDIT_GID: | |
b63862f4 | 630 | result = audit_comparator(cb->creds.gid, op, value); |
5bb289b5 DW |
631 | break; |
632 | case AUDIT_LOGINUID: | |
b63862f4 | 633 | result = audit_comparator(cb->loginuid, op, value); |
5bb289b5 DW |
634 | break; |
635 | } | |
636 | ||
5bb289b5 DW |
637 | if (!result) |
638 | return 0; | |
639 | } | |
640 | switch (rule->action) { | |
641 | case AUDIT_NEVER: *state = AUDIT_DISABLED; break; | |
642 | case AUDIT_POSSIBLE: *state = AUDIT_BUILD_CONTEXT; break; | |
643 | case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; | |
644 | } | |
645 | return 1; | |
646 | } | |
647 | ||
648 | int audit_filter_user(struct netlink_skb_parms *cb, int type) | |
0f45aa18 DW |
649 | { |
650 | struct audit_entry *e; | |
651 | enum audit_state state; | |
4a4cd633 | 652 | int ret = 1; |
0f45aa18 DW |
653 | |
654 | rcu_read_lock(); | |
655 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { | |
5bb289b5 | 656 | if (audit_filter_user_rules(cb, &e->rule, &state)) { |
4a4cd633 DW |
657 | if (state == AUDIT_DISABLED) |
658 | ret = 0; | |
659 | break; | |
0f45aa18 DW |
660 | } |
661 | } | |
662 | rcu_read_unlock(); | |
4a4cd633 | 663 | |
993e2d41 | 664 | return ret; /* Audit by default */ |
0f45aa18 DW |
665 | } |
666 | ||
c8edc80c DK |
667 | int audit_filter_type(int type) |
668 | { | |
669 | struct audit_entry *e; | |
670 | int result = 0; | |
671 | ||
672 | rcu_read_lock(); | |
673 | if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE])) | |
674 | goto unlock_and_return; | |
675 | ||
676 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE], | |
677 | list) { | |
678 | struct audit_rule *rule = &e->rule; | |
679 | int i; | |
680 | for (i = 0; i < rule->field_count; i++) { | |
681 | u32 field = rule->fields[i] & ~AUDIT_OPERATORS; | |
682 | u32 op = rule->fields[i] & AUDIT_OPERATORS; | |
683 | u32 value = rule->values[i]; | |
684 | if ( field == AUDIT_MSGTYPE ) { | |
685 | result = audit_comparator(type, op, value); | |
686 | if (!result) | |
687 | break; | |
688 | } | |
689 | } | |
690 | if (result) | |
691 | goto unlock_and_return; | |
692 | } | |
693 | unlock_and_return: | |
694 | rcu_read_unlock(); | |
695 | return result; | |
696 | } | |
697 | ||
698 | ||
1da177e4 LT |
699 | /* This should be called with task_lock() held. */ |
700 | static inline struct audit_context *audit_get_context(struct task_struct *tsk, | |
701 | int return_valid, | |
702 | int return_code) | |
703 | { | |
704 | struct audit_context *context = tsk->audit_context; | |
705 | ||
706 | if (likely(!context)) | |
707 | return NULL; | |
708 | context->return_valid = return_valid; | |
709 | context->return_code = return_code; | |
710 | ||
21af6c4f | 711 | if (context->in_syscall && !context->auditable) { |
1da177e4 | 712 | enum audit_state state; |
0f45aa18 | 713 | state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); |
1da177e4 LT |
714 | if (state == AUDIT_RECORD_CONTEXT) |
715 | context->auditable = 1; | |
716 | } | |
717 | ||
718 | context->pid = tsk->pid; | |
719 | context->uid = tsk->uid; | |
720 | context->gid = tsk->gid; | |
721 | context->euid = tsk->euid; | |
722 | context->suid = tsk->suid; | |
723 | context->fsuid = tsk->fsuid; | |
724 | context->egid = tsk->egid; | |
725 | context->sgid = tsk->sgid; | |
726 | context->fsgid = tsk->fsgid; | |
727 | context->personality = tsk->personality; | |
728 | tsk->audit_context = NULL; | |
729 | return context; | |
730 | } | |
731 | ||
732 | static inline void audit_free_names(struct audit_context *context) | |
733 | { | |
734 | int i; | |
735 | ||
736 | #if AUDIT_DEBUG == 2 | |
737 | if (context->auditable | |
738 | ||context->put_count + context->ino_count != context->name_count) { | |
73241ccc | 739 | printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d" |
1da177e4 LT |
740 | " name_count=%d put_count=%d" |
741 | " ino_count=%d [NOT freeing]\n", | |
73241ccc | 742 | __FILE__, __LINE__, |
1da177e4 LT |
743 | context->serial, context->major, context->in_syscall, |
744 | context->name_count, context->put_count, | |
745 | context->ino_count); | |
746 | for (i = 0; i < context->name_count; i++) | |
747 | printk(KERN_ERR "names[%d] = %p = %s\n", i, | |
748 | context->names[i].name, | |
73241ccc | 749 | context->names[i].name ?: "(null)"); |
1da177e4 LT |
750 | dump_stack(); |
751 | return; | |
752 | } | |
753 | #endif | |
754 | #if AUDIT_DEBUG | |
755 | context->put_count = 0; | |
756 | context->ino_count = 0; | |
757 | #endif | |
758 | ||
759 | for (i = 0; i < context->name_count; i++) | |
760 | if (context->names[i].name) | |
761 | __putname(context->names[i].name); | |
762 | context->name_count = 0; | |
8f37d47c DW |
763 | if (context->pwd) |
764 | dput(context->pwd); | |
765 | if (context->pwdmnt) | |
766 | mntput(context->pwdmnt); | |
767 | context->pwd = NULL; | |
768 | context->pwdmnt = NULL; | |
1da177e4 LT |
769 | } |
770 | ||
771 | static inline void audit_free_aux(struct audit_context *context) | |
772 | { | |
773 | struct audit_aux_data *aux; | |
774 | ||
775 | while ((aux = context->aux)) { | |
01116105 SS |
776 | if (aux->type == AUDIT_AVC_PATH) { |
777 | struct audit_aux_data_path *axi = (void *)aux; | |
778 | dput(axi->dentry); | |
779 | mntput(axi->mnt); | |
780 | } | |
1da177e4 LT |
781 | context->aux = aux->next; |
782 | kfree(aux); | |
783 | } | |
784 | } | |
785 | ||
786 | static inline void audit_zero_context(struct audit_context *context, | |
787 | enum audit_state state) | |
788 | { | |
789 | uid_t loginuid = context->loginuid; | |
790 | ||
791 | memset(context, 0, sizeof(*context)); | |
792 | context->state = state; | |
793 | context->loginuid = loginuid; | |
794 | } | |
795 | ||
796 | static inline struct audit_context *audit_alloc_context(enum audit_state state) | |
797 | { | |
798 | struct audit_context *context; | |
799 | ||
800 | if (!(context = kmalloc(sizeof(*context), GFP_KERNEL))) | |
801 | return NULL; | |
802 | audit_zero_context(context, state); | |
803 | return context; | |
804 | } | |
805 | ||
b0dd25a8 RD |
806 | /** |
807 | * audit_alloc - allocate an audit context block for a task | |
808 | * @tsk: task | |
809 | * | |
810 | * Filter on the task information and allocate a per-task audit context | |
1da177e4 LT |
811 | * if necessary. Doing so turns on system call auditing for the |
812 | * specified task. This is called from copy_process, so no lock is | |
b0dd25a8 RD |
813 | * needed. |
814 | */ | |
1da177e4 LT |
815 | int audit_alloc(struct task_struct *tsk) |
816 | { | |
817 | struct audit_context *context; | |
818 | enum audit_state state; | |
819 | ||
820 | if (likely(!audit_enabled)) | |
821 | return 0; /* Return if not auditing. */ | |
822 | ||
823 | state = audit_filter_task(tsk); | |
824 | if (likely(state == AUDIT_DISABLED)) | |
825 | return 0; | |
826 | ||
827 | if (!(context = audit_alloc_context(state))) { | |
828 | audit_log_lost("out of memory in audit_alloc"); | |
829 | return -ENOMEM; | |
830 | } | |
831 | ||
832 | /* Preserve login uid */ | |
833 | context->loginuid = -1; | |
834 | if (current->audit_context) | |
835 | context->loginuid = current->audit_context->loginuid; | |
836 | ||
837 | tsk->audit_context = context; | |
838 | set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); | |
839 | return 0; | |
840 | } | |
841 | ||
842 | static inline void audit_free_context(struct audit_context *context) | |
843 | { | |
844 | struct audit_context *previous; | |
845 | int count = 0; | |
846 | ||
847 | do { | |
848 | previous = context->previous; | |
849 | if (previous || (count && count < 10)) { | |
850 | ++count; | |
851 | printk(KERN_ERR "audit(:%d): major=%d name_count=%d:" | |
852 | " freeing multiple contexts (%d)\n", | |
853 | context->serial, context->major, | |
854 | context->name_count, count); | |
855 | } | |
856 | audit_free_names(context); | |
857 | audit_free_aux(context); | |
858 | kfree(context); | |
859 | context = previous; | |
860 | } while (context); | |
861 | if (count >= 10) | |
862 | printk(KERN_ERR "audit: freed %d contexts\n", count); | |
863 | } | |
864 | ||
219f0817 SS |
865 | static void audit_log_task_info(struct audit_buffer *ab) |
866 | { | |
867 | char name[sizeof(current->comm)]; | |
868 | struct mm_struct *mm = current->mm; | |
869 | struct vm_area_struct *vma; | |
870 | ||
871 | get_task_comm(name, current); | |
99e45eea DW |
872 | audit_log_format(ab, " comm="); |
873 | audit_log_untrustedstring(ab, name); | |
219f0817 SS |
874 | |
875 | if (!mm) | |
876 | return; | |
877 | ||
878 | down_read(&mm->mmap_sem); | |
879 | vma = mm->mmap; | |
880 | while (vma) { | |
881 | if ((vma->vm_flags & VM_EXECUTABLE) && | |
882 | vma->vm_file) { | |
883 | audit_log_d_path(ab, "exe=", | |
884 | vma->vm_file->f_dentry, | |
885 | vma->vm_file->f_vfsmnt); | |
886 | break; | |
887 | } | |
888 | vma = vma->vm_next; | |
889 | } | |
890 | up_read(&mm->mmap_sem); | |
891 | } | |
892 | ||
9796fdd8 | 893 | static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask) |
1da177e4 LT |
894 | { |
895 | int i; | |
896 | struct audit_buffer *ab; | |
7551ced3 | 897 | struct audit_aux_data *aux; |
1da177e4 | 898 | |
f5561964 | 899 | ab = audit_log_start(context, gfp_mask, AUDIT_SYSCALL); |
1da177e4 LT |
900 | if (!ab) |
901 | return; /* audit_panic has been called */ | |
bccf6ae0 DW |
902 | audit_log_format(ab, "arch=%x syscall=%d", |
903 | context->arch, context->major); | |
1da177e4 LT |
904 | if (context->personality != PER_LINUX) |
905 | audit_log_format(ab, " per=%lx", context->personality); | |
906 | if (context->return_valid) | |
2fd6f58b | 907 | audit_log_format(ab, " success=%s exit=%ld", |
908 | (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", | |
909 | context->return_code); | |
1da177e4 LT |
910 | audit_log_format(ab, |
911 | " a0=%lx a1=%lx a2=%lx a3=%lx items=%d" | |
326e9c8b SG |
912 | " pid=%d auid=%u uid=%u gid=%u" |
913 | " euid=%u suid=%u fsuid=%u" | |
914 | " egid=%u sgid=%u fsgid=%u", | |
1da177e4 LT |
915 | context->argv[0], |
916 | context->argv[1], | |
917 | context->argv[2], | |
918 | context->argv[3], | |
919 | context->name_count, | |
920 | context->pid, | |
921 | context->loginuid, | |
922 | context->uid, | |
923 | context->gid, | |
924 | context->euid, context->suid, context->fsuid, | |
925 | context->egid, context->sgid, context->fsgid); | |
219f0817 | 926 | audit_log_task_info(ab); |
1da177e4 | 927 | audit_log_end(ab); |
1da177e4 | 928 | |
7551ced3 | 929 | for (aux = context->aux; aux; aux = aux->next) { |
c0404993 | 930 | |
ef20c8c1 | 931 | ab = audit_log_start(context, gfp_mask, aux->type); |
1da177e4 LT |
932 | if (!ab) |
933 | continue; /* audit_panic has been called */ | |
934 | ||
1da177e4 | 935 | switch (aux->type) { |
c0404993 | 936 | case AUDIT_IPC: { |
1da177e4 LT |
937 | struct audit_aux_data_ipcctl *axi = (void *)aux; |
938 | audit_log_format(ab, | |
326e9c8b | 939 | " qbytes=%lx iuid=%u igid=%u mode=%x", |
1da177e4 | 940 | axi->qbytes, axi->uid, axi->gid, axi->mode); |
3ec3b2fb DW |
941 | break; } |
942 | ||
943 | case AUDIT_SOCKETCALL: { | |
944 | int i; | |
945 | struct audit_aux_data_socketcall *axs = (void *)aux; | |
946 | audit_log_format(ab, "nargs=%d", axs->nargs); | |
947 | for (i=0; i<axs->nargs; i++) | |
948 | audit_log_format(ab, " a%d=%lx", i, axs->args[i]); | |
949 | break; } | |
950 | ||
951 | case AUDIT_SOCKADDR: { | |
952 | struct audit_aux_data_sockaddr *axs = (void *)aux; | |
953 | ||
954 | audit_log_format(ab, "saddr="); | |
955 | audit_log_hex(ab, axs->a, axs->len); | |
956 | break; } | |
01116105 SS |
957 | |
958 | case AUDIT_AVC_PATH: { | |
959 | struct audit_aux_data_path *axi = (void *)aux; | |
960 | audit_log_d_path(ab, "path=", axi->dentry, axi->mnt); | |
01116105 SS |
961 | break; } |
962 | ||
1da177e4 LT |
963 | } |
964 | audit_log_end(ab); | |
1da177e4 LT |
965 | } |
966 | ||
8f37d47c | 967 | if (context->pwd && context->pwdmnt) { |
ef20c8c1 | 968 | ab = audit_log_start(context, gfp_mask, AUDIT_CWD); |
8f37d47c DW |
969 | if (ab) { |
970 | audit_log_d_path(ab, "cwd=", context->pwd, context->pwdmnt); | |
971 | audit_log_end(ab); | |
972 | } | |
973 | } | |
1da177e4 | 974 | for (i = 0; i < context->name_count; i++) { |
73241ccc AG |
975 | unsigned long ino = context->names[i].ino; |
976 | unsigned long pino = context->names[i].pino; | |
977 | ||
ef20c8c1 | 978 | ab = audit_log_start(context, gfp_mask, AUDIT_PATH); |
1da177e4 LT |
979 | if (!ab) |
980 | continue; /* audit_panic has been called */ | |
8f37d47c | 981 | |
1da177e4 | 982 | audit_log_format(ab, "item=%d", i); |
73241ccc AG |
983 | |
984 | audit_log_format(ab, " name="); | |
985 | if (context->names[i].name) | |
83c7d091 | 986 | audit_log_untrustedstring(ab, context->names[i].name); |
73241ccc AG |
987 | else |
988 | audit_log_format(ab, "(null)"); | |
989 | ||
990 | if (pino != (unsigned long)-1) | |
991 | audit_log_format(ab, " parent=%lu", pino); | |
992 | if (ino != (unsigned long)-1) | |
993 | audit_log_format(ab, " inode=%lu", ino); | |
994 | if ((pino != (unsigned long)-1) || (ino != (unsigned long)-1)) | |
995 | audit_log_format(ab, " dev=%02x:%02x mode=%#o" | |
996 | " ouid=%u ogid=%u rdev=%02x:%02x", | |
997 | MAJOR(context->names[i].dev), | |
998 | MINOR(context->names[i].dev), | |
999 | context->names[i].mode, | |
1000 | context->names[i].uid, | |
1001 | context->names[i].gid, | |
1002 | MAJOR(context->names[i].rdev), | |
1da177e4 LT |
1003 | MINOR(context->names[i].rdev)); |
1004 | audit_log_end(ab); | |
1005 | } | |
1006 | } | |
1007 | ||
b0dd25a8 RD |
1008 | /** |
1009 | * audit_free - free a per-task audit context | |
1010 | * @tsk: task whose audit context block to free | |
1011 | * | |
1012 | * Called from copy_process and __put_task_struct. | |
1013 | */ | |
1da177e4 LT |
1014 | void audit_free(struct task_struct *tsk) |
1015 | { | |
1016 | struct audit_context *context; | |
1017 | ||
1018 | task_lock(tsk); | |
1019 | context = audit_get_context(tsk, 0, 0); | |
1020 | task_unlock(tsk); | |
1021 | ||
1022 | if (likely(!context)) | |
1023 | return; | |
1024 | ||
1025 | /* Check for system calls that do not go through the exit | |
f5561964 DW |
1026 | * function (e.g., exit_group), then free context block. |
1027 | * We use GFP_ATOMIC here because we might be doing this | |
1028 | * in the context of the idle thread */ | |
f7056d64 | 1029 | if (context->in_syscall && context->auditable) |
f5561964 | 1030 | audit_log_exit(context, GFP_ATOMIC); |
1da177e4 LT |
1031 | |
1032 | audit_free_context(context); | |
1033 | } | |
1034 | ||
b0dd25a8 RD |
1035 | /** |
1036 | * audit_syscall_entry - fill in an audit record at syscall entry | |
1037 | * @tsk: task being audited | |
1038 | * @arch: architecture type | |
1039 | * @major: major syscall type (function) | |
1040 | * @a1: additional syscall register 1 | |
1041 | * @a2: additional syscall register 2 | |
1042 | * @a3: additional syscall register 3 | |
1043 | * @a4: additional syscall register 4 | |
1044 | * | |
1045 | * Fill in audit context at syscall entry. This only happens if the | |
1da177e4 LT |
1046 | * audit context was created when the task was created and the state or |
1047 | * filters demand the audit context be built. If the state from the | |
1048 | * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, | |
1049 | * then the record will be written at syscall exit time (otherwise, it | |
1050 | * will only be written if another part of the kernel requests that it | |
b0dd25a8 RD |
1051 | * be written). |
1052 | */ | |
2fd6f58b | 1053 | void audit_syscall_entry(struct task_struct *tsk, int arch, int major, |
1da177e4 LT |
1054 | unsigned long a1, unsigned long a2, |
1055 | unsigned long a3, unsigned long a4) | |
1056 | { | |
1057 | struct audit_context *context = tsk->audit_context; | |
1058 | enum audit_state state; | |
1059 | ||
1060 | BUG_ON(!context); | |
1061 | ||
b0dd25a8 RD |
1062 | /* |
1063 | * This happens only on certain architectures that make system | |
1da177e4 LT |
1064 | * calls in kernel_thread via the entry.S interface, instead of |
1065 | * with direct calls. (If you are porting to a new | |
1066 | * architecture, hitting this condition can indicate that you | |
1067 | * got the _exit/_leave calls backward in entry.S.) | |
1068 | * | |
1069 | * i386 no | |
1070 | * x86_64 no | |
1071 | * ppc64 yes (see arch/ppc64/kernel/misc.S) | |
1072 | * | |
1073 | * This also happens with vm86 emulation in a non-nested manner | |
1074 | * (entries without exits), so this case must be caught. | |
1075 | */ | |
1076 | if (context->in_syscall) { | |
1077 | struct audit_context *newctx; | |
1078 | ||
1da177e4 LT |
1079 | #if AUDIT_DEBUG |
1080 | printk(KERN_ERR | |
1081 | "audit(:%d) pid=%d in syscall=%d;" | |
1082 | " entering syscall=%d\n", | |
1083 | context->serial, tsk->pid, context->major, major); | |
1084 | #endif | |
1085 | newctx = audit_alloc_context(context->state); | |
1086 | if (newctx) { | |
1087 | newctx->previous = context; | |
1088 | context = newctx; | |
1089 | tsk->audit_context = newctx; | |
1090 | } else { | |
1091 | /* If we can't alloc a new context, the best we | |
1092 | * can do is to leak memory (any pending putname | |
1093 | * will be lost). The only other alternative is | |
1094 | * to abandon auditing. */ | |
1095 | audit_zero_context(context, context->state); | |
1096 | } | |
1097 | } | |
1098 | BUG_ON(context->in_syscall || context->name_count); | |
1099 | ||
1100 | if (!audit_enabled) | |
1101 | return; | |
1102 | ||
2fd6f58b | 1103 | context->arch = arch; |
1da177e4 LT |
1104 | context->major = major; |
1105 | context->argv[0] = a1; | |
1106 | context->argv[1] = a2; | |
1107 | context->argv[2] = a3; | |
1108 | context->argv[3] = a4; | |
1109 | ||
1110 | state = context->state; | |
1111 | if (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT) | |
0f45aa18 | 1112 | state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); |
1da177e4 LT |
1113 | if (likely(state == AUDIT_DISABLED)) |
1114 | return; | |
1115 | ||
ce625a80 | 1116 | context->serial = 0; |
1da177e4 LT |
1117 | context->ctime = CURRENT_TIME; |
1118 | context->in_syscall = 1; | |
1119 | context->auditable = !!(state == AUDIT_RECORD_CONTEXT); | |
1120 | } | |
1121 | ||
b0dd25a8 RD |
1122 | /** |
1123 | * audit_syscall_exit - deallocate audit context after a system call | |
1124 | * @tsk: task being audited | |
1125 | * @valid: success/failure flag | |
1126 | * @return_code: syscall return value | |
1127 | * | |
1128 | * Tear down after system call. If the audit context has been marked as | |
1da177e4 LT |
1129 | * auditable (either because of the AUDIT_RECORD_CONTEXT state from |
1130 | * filtering, or because some other part of the kernel write an audit | |
1131 | * message), then write out the syscall information. In call cases, | |
b0dd25a8 RD |
1132 | * free the names stored from getname(). |
1133 | */ | |
2fd6f58b | 1134 | void audit_syscall_exit(struct task_struct *tsk, int valid, long return_code) |
1da177e4 LT |
1135 | { |
1136 | struct audit_context *context; | |
1137 | ||
1138 | get_task_struct(tsk); | |
1139 | task_lock(tsk); | |
2fd6f58b | 1140 | context = audit_get_context(tsk, valid, return_code); |
1da177e4 LT |
1141 | task_unlock(tsk); |
1142 | ||
1143 | /* Not having a context here is ok, since the parent may have | |
1144 | * called __put_task_struct. */ | |
1145 | if (likely(!context)) | |
413a1c75 | 1146 | goto out; |
1da177e4 | 1147 | |
f7056d64 | 1148 | if (context->in_syscall && context->auditable) |
f5561964 | 1149 | audit_log_exit(context, GFP_KERNEL); |
1da177e4 LT |
1150 | |
1151 | context->in_syscall = 0; | |
1152 | context->auditable = 0; | |
2fd6f58b | 1153 | |
1da177e4 LT |
1154 | if (context->previous) { |
1155 | struct audit_context *new_context = context->previous; | |
1156 | context->previous = NULL; | |
1157 | audit_free_context(context); | |
1158 | tsk->audit_context = new_context; | |
1159 | } else { | |
1160 | audit_free_names(context); | |
1161 | audit_free_aux(context); | |
1da177e4 LT |
1162 | tsk->audit_context = context; |
1163 | } | |
413a1c75 | 1164 | out: |
1da177e4 LT |
1165 | put_task_struct(tsk); |
1166 | } | |
1167 | ||
b0dd25a8 RD |
1168 | /** |
1169 | * audit_getname - add a name to the list | |
1170 | * @name: name to add | |
1171 | * | |
1172 | * Add a name to the list of audit names for this context. | |
1173 | * Called from fs/namei.c:getname(). | |
1174 | */ | |
1da177e4 LT |
1175 | void audit_getname(const char *name) |
1176 | { | |
1177 | struct audit_context *context = current->audit_context; | |
1178 | ||
1179 | if (!context || IS_ERR(name) || !name) | |
1180 | return; | |
1181 | ||
1182 | if (!context->in_syscall) { | |
1183 | #if AUDIT_DEBUG == 2 | |
1184 | printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n", | |
1185 | __FILE__, __LINE__, context->serial, name); | |
1186 | dump_stack(); | |
1187 | #endif | |
1188 | return; | |
1189 | } | |
1190 | BUG_ON(context->name_count >= AUDIT_NAMES); | |
1191 | context->names[context->name_count].name = name; | |
1192 | context->names[context->name_count].ino = (unsigned long)-1; | |
1193 | ++context->name_count; | |
8f37d47c DW |
1194 | if (!context->pwd) { |
1195 | read_lock(¤t->fs->lock); | |
1196 | context->pwd = dget(current->fs->pwd); | |
1197 | context->pwdmnt = mntget(current->fs->pwdmnt); | |
1198 | read_unlock(¤t->fs->lock); | |
1199 | } | |
1200 | ||
1da177e4 LT |
1201 | } |
1202 | ||
b0dd25a8 RD |
1203 | /* audit_putname - intercept a putname request |
1204 | * @name: name to intercept and delay for putname | |
1205 | * | |
1206 | * If we have stored the name from getname in the audit context, | |
1207 | * then we delay the putname until syscall exit. | |
1208 | * Called from include/linux/fs.h:putname(). | |
1209 | */ | |
1da177e4 LT |
1210 | void audit_putname(const char *name) |
1211 | { | |
1212 | struct audit_context *context = current->audit_context; | |
1213 | ||
1214 | BUG_ON(!context); | |
1215 | if (!context->in_syscall) { | |
1216 | #if AUDIT_DEBUG == 2 | |
1217 | printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n", | |
1218 | __FILE__, __LINE__, context->serial, name); | |
1219 | if (context->name_count) { | |
1220 | int i; | |
1221 | for (i = 0; i < context->name_count; i++) | |
1222 | printk(KERN_ERR "name[%d] = %p = %s\n", i, | |
1223 | context->names[i].name, | |
73241ccc | 1224 | context->names[i].name ?: "(null)"); |
1da177e4 LT |
1225 | } |
1226 | #endif | |
1227 | __putname(name); | |
1228 | } | |
1229 | #if AUDIT_DEBUG | |
1230 | else { | |
1231 | ++context->put_count; | |
1232 | if (context->put_count > context->name_count) { | |
1233 | printk(KERN_ERR "%s:%d(:%d): major=%d" | |
1234 | " in_syscall=%d putname(%p) name_count=%d" | |
1235 | " put_count=%d\n", | |
1236 | __FILE__, __LINE__, | |
1237 | context->serial, context->major, | |
1238 | context->in_syscall, name, context->name_count, | |
1239 | context->put_count); | |
1240 | dump_stack(); | |
1241 | } | |
1242 | } | |
1243 | #endif | |
1244 | } | |
1245 | ||
b0dd25a8 RD |
1246 | /** |
1247 | * audit_inode - store the inode and device from a lookup | |
1248 | * @name: name being audited | |
1249 | * @inode: inode being audited | |
1250 | * @flags: lookup flags (as used in path_lookup()) | |
1251 | * | |
1252 | * Called from fs/namei.c:path_lookup(). | |
1253 | */ | |
73241ccc | 1254 | void __audit_inode(const char *name, const struct inode *inode, unsigned flags) |
1da177e4 LT |
1255 | { |
1256 | int idx; | |
1257 | struct audit_context *context = current->audit_context; | |
1258 | ||
1259 | if (!context->in_syscall) | |
1260 | return; | |
1261 | if (context->name_count | |
1262 | && context->names[context->name_count-1].name | |
1263 | && context->names[context->name_count-1].name == name) | |
1264 | idx = context->name_count - 1; | |
1265 | else if (context->name_count > 1 | |
1266 | && context->names[context->name_count-2].name | |
1267 | && context->names[context->name_count-2].name == name) | |
1268 | idx = context->name_count - 2; | |
1269 | else { | |
1270 | /* FIXME: how much do we care about inodes that have no | |
1271 | * associated name? */ | |
1272 | if (context->name_count >= AUDIT_NAMES - AUDIT_NAMES_RESERVED) | |
1273 | return; | |
1274 | idx = context->name_count++; | |
1275 | context->names[idx].name = NULL; | |
1276 | #if AUDIT_DEBUG | |
1277 | ++context->ino_count; | |
1278 | #endif | |
1279 | } | |
ae7b961b DW |
1280 | context->names[idx].dev = inode->i_sb->s_dev; |
1281 | context->names[idx].mode = inode->i_mode; | |
1282 | context->names[idx].uid = inode->i_uid; | |
1283 | context->names[idx].gid = inode->i_gid; | |
1284 | context->names[idx].rdev = inode->i_rdev; | |
73241ccc AG |
1285 | if ((flags & LOOKUP_PARENT) && (strcmp(name, "/") != 0) && |
1286 | (strcmp(name, ".") != 0)) { | |
1287 | context->names[idx].ino = (unsigned long)-1; | |
1288 | context->names[idx].pino = inode->i_ino; | |
1289 | } else { | |
1290 | context->names[idx].ino = inode->i_ino; | |
1291 | context->names[idx].pino = (unsigned long)-1; | |
1292 | } | |
1293 | } | |
1294 | ||
1295 | /** | |
1296 | * audit_inode_child - collect inode info for created/removed objects | |
1297 | * @dname: inode's dentry name | |
1298 | * @inode: inode being audited | |
1299 | * @pino: inode number of dentry parent | |
1300 | * | |
1301 | * For syscalls that create or remove filesystem objects, audit_inode | |
1302 | * can only collect information for the filesystem object's parent. | |
1303 | * This call updates the audit context with the child's information. | |
1304 | * Syscalls that create a new filesystem object must be hooked after | |
1305 | * the object is created. Syscalls that remove a filesystem object | |
1306 | * must be hooked prior, in order to capture the target inode during | |
1307 | * unsuccessful attempts. | |
1308 | */ | |
1309 | void __audit_inode_child(const char *dname, const struct inode *inode, | |
1310 | unsigned long pino) | |
1311 | { | |
1312 | int idx; | |
1313 | struct audit_context *context = current->audit_context; | |
1314 | ||
1315 | if (!context->in_syscall) | |
1316 | return; | |
1317 | ||
1318 | /* determine matching parent */ | |
1319 | if (dname) | |
1320 | for (idx = 0; idx < context->name_count; idx++) | |
1321 | if (context->names[idx].pino == pino) { | |
1322 | const char *n; | |
1323 | const char *name = context->names[idx].name; | |
1324 | int dlen = strlen(dname); | |
1325 | int nlen = name ? strlen(name) : 0; | |
1326 | ||
1327 | if (nlen < dlen) | |
1328 | continue; | |
1329 | ||
1330 | /* disregard trailing slashes */ | |
1331 | n = name + nlen - 1; | |
1332 | while ((*n == '/') && (n > name)) | |
1333 | n--; | |
1334 | ||
1335 | /* find last path component */ | |
1336 | n = n - dlen + 1; | |
1337 | if (n < name) | |
1338 | continue; | |
1339 | else if (n > name) { | |
1340 | if (*--n != '/') | |
1341 | continue; | |
1342 | else | |
1343 | n++; | |
1344 | } | |
1345 | ||
1346 | if (strncmp(n, dname, dlen) == 0) | |
1347 | goto update_context; | |
1348 | } | |
1349 | ||
1350 | /* catch-all in case match not found */ | |
1351 | idx = context->name_count++; | |
1352 | context->names[idx].name = NULL; | |
1353 | context->names[idx].pino = pino; | |
1354 | #if AUDIT_DEBUG | |
1355 | context->ino_count++; | |
1356 | #endif | |
1357 | ||
1358 | update_context: | |
1359 | if (inode) { | |
1360 | context->names[idx].ino = inode->i_ino; | |
1361 | context->names[idx].dev = inode->i_sb->s_dev; | |
1362 | context->names[idx].mode = inode->i_mode; | |
1363 | context->names[idx].uid = inode->i_uid; | |
1364 | context->names[idx].gid = inode->i_gid; | |
1365 | context->names[idx].rdev = inode->i_rdev; | |
1366 | } | |
1da177e4 LT |
1367 | } |
1368 | ||
b0dd25a8 RD |
1369 | /** |
1370 | * auditsc_get_stamp - get local copies of audit_context values | |
1371 | * @ctx: audit_context for the task | |
1372 | * @t: timespec to store time recorded in the audit_context | |
1373 | * @serial: serial value that is recorded in the audit_context | |
1374 | * | |
1375 | * Also sets the context as auditable. | |
1376 | */ | |
bfb4496e DW |
1377 | void auditsc_get_stamp(struct audit_context *ctx, |
1378 | struct timespec *t, unsigned int *serial) | |
1da177e4 | 1379 | { |
ce625a80 DW |
1380 | if (!ctx->serial) |
1381 | ctx->serial = audit_serial(); | |
bfb4496e DW |
1382 | t->tv_sec = ctx->ctime.tv_sec; |
1383 | t->tv_nsec = ctx->ctime.tv_nsec; | |
1384 | *serial = ctx->serial; | |
1385 | ctx->auditable = 1; | |
1da177e4 LT |
1386 | } |
1387 | ||
b0dd25a8 RD |
1388 | /** |
1389 | * audit_set_loginuid - set a task's audit_context loginuid | |
1390 | * @task: task whose audit context is being modified | |
1391 | * @loginuid: loginuid value | |
1392 | * | |
1393 | * Returns 0. | |
1394 | * | |
1395 | * Called (set) from fs/proc/base.c::proc_loginuid_write(). | |
1396 | */ | |
456be6cd | 1397 | int audit_set_loginuid(struct task_struct *task, uid_t loginuid) |
1da177e4 | 1398 | { |
456be6cd | 1399 | if (task->audit_context) { |
c0404993 SG |
1400 | struct audit_buffer *ab; |
1401 | ||
9ad9ad38 | 1402 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); |
c0404993 SG |
1403 | if (ab) { |
1404 | audit_log_format(ab, "login pid=%d uid=%u " | |
326e9c8b | 1405 | "old auid=%u new auid=%u", |
c0404993 SG |
1406 | task->pid, task->uid, |
1407 | task->audit_context->loginuid, loginuid); | |
1408 | audit_log_end(ab); | |
1409 | } | |
456be6cd | 1410 | task->audit_context->loginuid = loginuid; |
1da177e4 LT |
1411 | } |
1412 | return 0; | |
1413 | } | |
1414 | ||
b0dd25a8 RD |
1415 | /** |
1416 | * audit_get_loginuid - get the loginuid for an audit_context | |
1417 | * @ctx: the audit_context | |
1418 | * | |
1419 | * Returns the context's loginuid or -1 if @ctx is NULL. | |
1420 | */ | |
1da177e4 LT |
1421 | uid_t audit_get_loginuid(struct audit_context *ctx) |
1422 | { | |
1423 | return ctx ? ctx->loginuid : -1; | |
1424 | } | |
1425 | ||
b0dd25a8 RD |
1426 | /** |
1427 | * audit_ipc_perms - record audit data for ipc | |
1428 | * @qbytes: msgq bytes | |
1429 | * @uid: msgq user id | |
1430 | * @gid: msgq group id | |
1431 | * @mode: msgq mode (permissions) | |
1432 | * | |
1433 | * Returns 0 for success or NULL context or < 0 on error. | |
1434 | */ | |
1da177e4 LT |
1435 | int audit_ipc_perms(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) |
1436 | { | |
1437 | struct audit_aux_data_ipcctl *ax; | |
1438 | struct audit_context *context = current->audit_context; | |
1439 | ||
1440 | if (likely(!context)) | |
1441 | return 0; | |
1442 | ||
1443 | ax = kmalloc(sizeof(*ax), GFP_KERNEL); | |
1444 | if (!ax) | |
1445 | return -ENOMEM; | |
1446 | ||
1447 | ax->qbytes = qbytes; | |
1448 | ax->uid = uid; | |
1449 | ax->gid = gid; | |
1450 | ax->mode = mode; | |
1451 | ||
c0404993 | 1452 | ax->d.type = AUDIT_IPC; |
1da177e4 LT |
1453 | ax->d.next = context->aux; |
1454 | context->aux = (void *)ax; | |
1455 | return 0; | |
1456 | } | |
c2f0c7c3 | 1457 | |
b0dd25a8 RD |
1458 | /** |
1459 | * audit_socketcall - record audit data for sys_socketcall | |
1460 | * @nargs: number of args | |
1461 | * @args: args array | |
1462 | * | |
1463 | * Returns 0 for success or NULL context or < 0 on error. | |
1464 | */ | |
3ec3b2fb DW |
1465 | int audit_socketcall(int nargs, unsigned long *args) |
1466 | { | |
1467 | struct audit_aux_data_socketcall *ax; | |
1468 | struct audit_context *context = current->audit_context; | |
1469 | ||
1470 | if (likely(!context)) | |
1471 | return 0; | |
1472 | ||
1473 | ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL); | |
1474 | if (!ax) | |
1475 | return -ENOMEM; | |
1476 | ||
1477 | ax->nargs = nargs; | |
1478 | memcpy(ax->args, args, nargs * sizeof(unsigned long)); | |
1479 | ||
1480 | ax->d.type = AUDIT_SOCKETCALL; | |
1481 | ax->d.next = context->aux; | |
1482 | context->aux = (void *)ax; | |
1483 | return 0; | |
1484 | } | |
1485 | ||
b0dd25a8 RD |
1486 | /** |
1487 | * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto | |
1488 | * @len: data length in user space | |
1489 | * @a: data address in kernel space | |
1490 | * | |
1491 | * Returns 0 for success or NULL context or < 0 on error. | |
1492 | */ | |
3ec3b2fb DW |
1493 | int audit_sockaddr(int len, void *a) |
1494 | { | |
1495 | struct audit_aux_data_sockaddr *ax; | |
1496 | struct audit_context *context = current->audit_context; | |
1497 | ||
1498 | if (likely(!context)) | |
1499 | return 0; | |
1500 | ||
1501 | ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL); | |
1502 | if (!ax) | |
1503 | return -ENOMEM; | |
1504 | ||
1505 | ax->len = len; | |
1506 | memcpy(ax->a, a, len); | |
1507 | ||
1508 | ax->d.type = AUDIT_SOCKADDR; | |
1509 | ax->d.next = context->aux; | |
1510 | context->aux = (void *)ax; | |
1511 | return 0; | |
1512 | } | |
1513 | ||
b0dd25a8 RD |
1514 | /** |
1515 | * audit_avc_path - record the granting or denial of permissions | |
1516 | * @dentry: dentry to record | |
1517 | * @mnt: mnt to record | |
1518 | * | |
1519 | * Returns 0 for success or NULL context or < 0 on error. | |
1520 | * | |
1521 | * Called from security/selinux/avc.c::avc_audit() | |
1522 | */ | |
01116105 SS |
1523 | int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt) |
1524 | { | |
1525 | struct audit_aux_data_path *ax; | |
1526 | struct audit_context *context = current->audit_context; | |
1527 | ||
1528 | if (likely(!context)) | |
1529 | return 0; | |
1530 | ||
1531 | ax = kmalloc(sizeof(*ax), GFP_ATOMIC); | |
1532 | if (!ax) | |
1533 | return -ENOMEM; | |
1534 | ||
1535 | ax->dentry = dget(dentry); | |
1536 | ax->mnt = mntget(mnt); | |
1537 | ||
1538 | ax->d.type = AUDIT_AVC_PATH; | |
1539 | ax->d.next = context->aux; | |
1540 | context->aux = (void *)ax; | |
1541 | return 0; | |
1542 | } | |
1543 | ||
b0dd25a8 RD |
1544 | /** |
1545 | * audit_signal_info - record signal info for shutting down audit subsystem | |
1546 | * @sig: signal value | |
1547 | * @t: task being signaled | |
1548 | * | |
1549 | * If the audit subsystem is being terminated, record the task (pid) | |
1550 | * and uid that is doing that. | |
1551 | */ | |
c2f0c7c3 SG |
1552 | void audit_signal_info(int sig, struct task_struct *t) |
1553 | { | |
1554 | extern pid_t audit_sig_pid; | |
1555 | extern uid_t audit_sig_uid; | |
c2f0c7c3 | 1556 | |
582edda5 | 1557 | if (unlikely(audit_pid && t->tgid == audit_pid)) { |
c2f0c7c3 SG |
1558 | if (sig == SIGTERM || sig == SIGHUP) { |
1559 | struct audit_context *ctx = current->audit_context; | |
1560 | audit_sig_pid = current->pid; | |
1561 | if (ctx) | |
1562 | audit_sig_uid = ctx->loginuid; | |
1563 | else | |
1564 | audit_sig_uid = current->uid; | |
1565 | } | |
1566 | } | |
1567 | } |