Commit | Line | Data |
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85c8721f | 1 | /* audit.c -- Auditing support |
1da177e4 LT |
2 | * Gateway between the kernel (e.g., selinux) and the user-space audit daemon. |
3 | * System-call specific features have moved to auditsc.c | |
4 | * | |
6a01b07f | 5 | * Copyright 2003-2007 Red Hat Inc., Durham, North Carolina. |
1da177e4 LT |
6 | * All Rights Reserved. |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License | |
19 | * along with this program; if not, write to the Free Software | |
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
21 | * | |
22 | * Written by Rickard E. (Rik) Faith <faith@redhat.com> | |
23 | * | |
d7a96f3a | 24 | * Goals: 1) Integrate fully with Security Modules. |
1da177e4 LT |
25 | * 2) Minimal run-time overhead: |
26 | * a) Minimal when syscall auditing is disabled (audit_enable=0). | |
27 | * b) Small when syscall auditing is enabled and no audit record | |
28 | * is generated (defer as much work as possible to record | |
29 | * generation time): | |
30 | * i) context is allocated, | |
31 | * ii) names from getname are stored without a copy, and | |
32 | * iii) inode information stored from path_lookup. | |
33 | * 3) Ability to disable syscall auditing at boot time (audit=0). | |
34 | * 4) Usable by other parts of the kernel (if audit_log* is called, | |
35 | * then a syscall record will be generated automatically for the | |
36 | * current syscall). | |
37 | * 5) Netlink interface to user-space. | |
38 | * 6) Support low-overhead kernel-based filtering to minimize the | |
39 | * information that must be passed to user-space. | |
40 | * | |
85c8721f | 41 | * Example user-space utilities: http://people.redhat.com/sgrubb/audit/ |
1da177e4 LT |
42 | */ |
43 | ||
44 | #include <linux/init.h> | |
1da177e4 | 45 | #include <asm/types.h> |
60063497 | 46 | #include <linux/atomic.h> |
1da177e4 | 47 | #include <linux/mm.h> |
9984de1a | 48 | #include <linux/export.h> |
5a0e3ad6 | 49 | #include <linux/slab.h> |
b7d11258 DW |
50 | #include <linux/err.h> |
51 | #include <linux/kthread.h> | |
1da177e4 LT |
52 | |
53 | #include <linux/audit.h> | |
54 | ||
55 | #include <net/sock.h> | |
93315ed6 | 56 | #include <net/netlink.h> |
1da177e4 | 57 | #include <linux/skbuff.h> |
131ad62d MDF |
58 | #ifdef CONFIG_SECURITY |
59 | #include <linux/security.h> | |
60 | #endif | |
1da177e4 | 61 | #include <linux/netlink.h> |
7dfb7103 | 62 | #include <linux/freezer.h> |
522ed776 | 63 | #include <linux/tty.h> |
34e36d8e | 64 | #include <linux/pid_namespace.h> |
3dc7e315 DG |
65 | |
66 | #include "audit.h" | |
1da177e4 | 67 | |
a3f07114 | 68 | /* No auditing will take place until audit_initialized == AUDIT_INITIALIZED. |
1da177e4 | 69 | * (Initialization happens after skb_init is called.) */ |
a3f07114 EP |
70 | #define AUDIT_DISABLED -1 |
71 | #define AUDIT_UNINITIALIZED 0 | |
72 | #define AUDIT_INITIALIZED 1 | |
1da177e4 LT |
73 | static int audit_initialized; |
74 | ||
1a6b9f23 EP |
75 | #define AUDIT_OFF 0 |
76 | #define AUDIT_ON 1 | |
77 | #define AUDIT_LOCKED 2 | |
1da177e4 | 78 | int audit_enabled; |
b593d384 | 79 | int audit_ever_enabled; |
1da177e4 | 80 | |
ae9d67af JE |
81 | EXPORT_SYMBOL_GPL(audit_enabled); |
82 | ||
1da177e4 LT |
83 | /* Default state when kernel boots without any parameters. */ |
84 | static int audit_default; | |
85 | ||
86 | /* If auditing cannot proceed, audit_failure selects what happens. */ | |
87 | static int audit_failure = AUDIT_FAIL_PRINTK; | |
88 | ||
75c0371a PE |
89 | /* |
90 | * If audit records are to be written to the netlink socket, audit_pid | |
15e47304 EB |
91 | * contains the pid of the auditd process and audit_nlk_portid contains |
92 | * the portid to use to send netlink messages to that process. | |
75c0371a | 93 | */ |
c2f0c7c3 | 94 | int audit_pid; |
15e47304 | 95 | static int audit_nlk_portid; |
1da177e4 | 96 | |
b0dd25a8 | 97 | /* If audit_rate_limit is non-zero, limit the rate of sending audit records |
1da177e4 LT |
98 | * to that number per second. This prevents DoS attacks, but results in |
99 | * audit records being dropped. */ | |
100 | static int audit_rate_limit; | |
101 | ||
102 | /* Number of outstanding audit_buffers allowed. */ | |
103 | static int audit_backlog_limit = 64; | |
ac4cec44 DW |
104 | static int audit_backlog_wait_time = 60 * HZ; |
105 | static int audit_backlog_wait_overflow = 0; | |
1da177e4 | 106 | |
c2f0c7c3 | 107 | /* The identity of the user shutting down the audit system. */ |
cca080d9 | 108 | kuid_t audit_sig_uid = INVALID_UID; |
c2f0c7c3 | 109 | pid_t audit_sig_pid = -1; |
e1396065 | 110 | u32 audit_sig_sid = 0; |
c2f0c7c3 | 111 | |
1da177e4 LT |
112 | /* Records can be lost in several ways: |
113 | 0) [suppressed in audit_alloc] | |
114 | 1) out of memory in audit_log_start [kmalloc of struct audit_buffer] | |
115 | 2) out of memory in audit_log_move [alloc_skb] | |
116 | 3) suppressed due to audit_rate_limit | |
117 | 4) suppressed due to audit_backlog_limit | |
118 | */ | |
119 | static atomic_t audit_lost = ATOMIC_INIT(0); | |
120 | ||
121 | /* The netlink socket. */ | |
122 | static struct sock *audit_sock; | |
123 | ||
f368c07d AG |
124 | /* Hash for inode-based rules */ |
125 | struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS]; | |
126 | ||
b7d11258 | 127 | /* The audit_freelist is a list of pre-allocated audit buffers (if more |
1da177e4 LT |
128 | * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of |
129 | * being placed on the freelist). */ | |
1da177e4 | 130 | static DEFINE_SPINLOCK(audit_freelist_lock); |
b0dd25a8 | 131 | static int audit_freelist_count; |
1da177e4 LT |
132 | static LIST_HEAD(audit_freelist); |
133 | ||
b7d11258 | 134 | static struct sk_buff_head audit_skb_queue; |
f3d357b0 EP |
135 | /* queue of skbs to send to auditd when/if it comes back */ |
136 | static struct sk_buff_head audit_skb_hold_queue; | |
b7d11258 DW |
137 | static struct task_struct *kauditd_task; |
138 | static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait); | |
9ad9ad38 | 139 | static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait); |
1da177e4 | 140 | |
f368c07d | 141 | /* Serialize requests from userspace. */ |
916d7576 | 142 | DEFINE_MUTEX(audit_cmd_mutex); |
1da177e4 LT |
143 | |
144 | /* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting | |
145 | * audit records. Since printk uses a 1024 byte buffer, this buffer | |
146 | * should be at least that large. */ | |
147 | #define AUDIT_BUFSIZ 1024 | |
148 | ||
149 | /* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the | |
150 | * audit_freelist. Doing so eliminates many kmalloc/kfree calls. */ | |
151 | #define AUDIT_MAXFREE (2*NR_CPUS) | |
152 | ||
153 | /* The audit_buffer is used when formatting an audit record. The caller | |
154 | * locks briefly to get the record off the freelist or to allocate the | |
155 | * buffer, and locks briefly to send the buffer to the netlink layer or | |
156 | * to place it on a transmit queue. Multiple audit_buffers can be in | |
157 | * use simultaneously. */ | |
158 | struct audit_buffer { | |
159 | struct list_head list; | |
8fc6115c | 160 | struct sk_buff *skb; /* formatted skb ready to send */ |
1da177e4 | 161 | struct audit_context *ctx; /* NULL or associated context */ |
9796fdd8 | 162 | gfp_t gfp_mask; |
1da177e4 LT |
163 | }; |
164 | ||
f09ac9db EP |
165 | struct audit_reply { |
166 | int pid; | |
167 | struct sk_buff *skb; | |
168 | }; | |
169 | ||
c0404993 SG |
170 | static void audit_set_pid(struct audit_buffer *ab, pid_t pid) |
171 | { | |
50397bd1 EP |
172 | if (ab) { |
173 | struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); | |
174 | nlh->nlmsg_pid = pid; | |
175 | } | |
c0404993 SG |
176 | } |
177 | ||
8c8570fb | 178 | void audit_panic(const char *message) |
1da177e4 LT |
179 | { |
180 | switch (audit_failure) | |
181 | { | |
182 | case AUDIT_FAIL_SILENT: | |
183 | break; | |
184 | case AUDIT_FAIL_PRINTK: | |
320f1b1e EP |
185 | if (printk_ratelimit()) |
186 | printk(KERN_ERR "audit: %s\n", message); | |
1da177e4 LT |
187 | break; |
188 | case AUDIT_FAIL_PANIC: | |
b29ee87e EP |
189 | /* test audit_pid since printk is always losey, why bother? */ |
190 | if (audit_pid) | |
191 | panic("audit: %s\n", message); | |
1da177e4 LT |
192 | break; |
193 | } | |
194 | } | |
195 | ||
196 | static inline int audit_rate_check(void) | |
197 | { | |
198 | static unsigned long last_check = 0; | |
199 | static int messages = 0; | |
200 | static DEFINE_SPINLOCK(lock); | |
201 | unsigned long flags; | |
202 | unsigned long now; | |
203 | unsigned long elapsed; | |
204 | int retval = 0; | |
205 | ||
206 | if (!audit_rate_limit) return 1; | |
207 | ||
208 | spin_lock_irqsave(&lock, flags); | |
209 | if (++messages < audit_rate_limit) { | |
210 | retval = 1; | |
211 | } else { | |
212 | now = jiffies; | |
213 | elapsed = now - last_check; | |
214 | if (elapsed > HZ) { | |
215 | last_check = now; | |
216 | messages = 0; | |
217 | retval = 1; | |
218 | } | |
219 | } | |
220 | spin_unlock_irqrestore(&lock, flags); | |
221 | ||
222 | return retval; | |
223 | } | |
224 | ||
b0dd25a8 RD |
225 | /** |
226 | * audit_log_lost - conditionally log lost audit message event | |
227 | * @message: the message stating reason for lost audit message | |
228 | * | |
229 | * Emit at least 1 message per second, even if audit_rate_check is | |
230 | * throttling. | |
231 | * Always increment the lost messages counter. | |
232 | */ | |
1da177e4 LT |
233 | void audit_log_lost(const char *message) |
234 | { | |
235 | static unsigned long last_msg = 0; | |
236 | static DEFINE_SPINLOCK(lock); | |
237 | unsigned long flags; | |
238 | unsigned long now; | |
239 | int print; | |
240 | ||
241 | atomic_inc(&audit_lost); | |
242 | ||
243 | print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit); | |
244 | ||
245 | if (!print) { | |
246 | spin_lock_irqsave(&lock, flags); | |
247 | now = jiffies; | |
248 | if (now - last_msg > HZ) { | |
249 | print = 1; | |
250 | last_msg = now; | |
251 | } | |
252 | spin_unlock_irqrestore(&lock, flags); | |
253 | } | |
254 | ||
255 | if (print) { | |
320f1b1e EP |
256 | if (printk_ratelimit()) |
257 | printk(KERN_WARNING | |
258 | "audit: audit_lost=%d audit_rate_limit=%d " | |
259 | "audit_backlog_limit=%d\n", | |
260 | atomic_read(&audit_lost), | |
261 | audit_rate_limit, | |
262 | audit_backlog_limit); | |
1da177e4 LT |
263 | audit_panic(message); |
264 | } | |
1da177e4 LT |
265 | } |
266 | ||
1a6b9f23 | 267 | static int audit_log_config_change(char *function_name, int new, int old, |
2532386f | 268 | int allow_changes) |
1da177e4 | 269 | { |
1a6b9f23 EP |
270 | struct audit_buffer *ab; |
271 | int rc = 0; | |
ce29b682 | 272 | |
1a6b9f23 | 273 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
0644ec0c KC |
274 | if (unlikely(!ab)) |
275 | return rc; | |
4d3fb709 EP |
276 | audit_log_format(ab, "%s=%d old=%d", function_name, new, old); |
277 | audit_log_session_info(ab); | |
b122c376 EP |
278 | rc = audit_log_task_context(ab); |
279 | if (rc) | |
280 | allow_changes = 0; /* Something weird, deny request */ | |
1a6b9f23 EP |
281 | audit_log_format(ab, " res=%d", allow_changes); |
282 | audit_log_end(ab); | |
6a01b07f | 283 | return rc; |
1da177e4 LT |
284 | } |
285 | ||
dc9eb698 | 286 | static int audit_do_config_change(char *function_name, int *to_change, int new) |
1da177e4 | 287 | { |
1a6b9f23 | 288 | int allow_changes, rc = 0, old = *to_change; |
6a01b07f SG |
289 | |
290 | /* check if we are locked */ | |
1a6b9f23 EP |
291 | if (audit_enabled == AUDIT_LOCKED) |
292 | allow_changes = 0; | |
6a01b07f | 293 | else |
1a6b9f23 | 294 | allow_changes = 1; |
ce29b682 | 295 | |
1a6b9f23 | 296 | if (audit_enabled != AUDIT_OFF) { |
dc9eb698 | 297 | rc = audit_log_config_change(function_name, new, old, allow_changes); |
1a6b9f23 EP |
298 | if (rc) |
299 | allow_changes = 0; | |
6a01b07f | 300 | } |
6a01b07f SG |
301 | |
302 | /* If we are allowed, make the change */ | |
1a6b9f23 EP |
303 | if (allow_changes == 1) |
304 | *to_change = new; | |
6a01b07f SG |
305 | /* Not allowed, update reason */ |
306 | else if (rc == 0) | |
307 | rc = -EPERM; | |
308 | return rc; | |
1da177e4 LT |
309 | } |
310 | ||
dc9eb698 | 311 | static int audit_set_rate_limit(int limit) |
1da177e4 | 312 | { |
dc9eb698 | 313 | return audit_do_config_change("audit_rate_limit", &audit_rate_limit, limit); |
1a6b9f23 | 314 | } |
ce29b682 | 315 | |
dc9eb698 | 316 | static int audit_set_backlog_limit(int limit) |
1a6b9f23 | 317 | { |
dc9eb698 | 318 | return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, limit); |
1a6b9f23 | 319 | } |
6a01b07f | 320 | |
dc9eb698 | 321 | static int audit_set_enabled(int state) |
1a6b9f23 | 322 | { |
b593d384 | 323 | int rc; |
1a6b9f23 EP |
324 | if (state < AUDIT_OFF || state > AUDIT_LOCKED) |
325 | return -EINVAL; | |
6a01b07f | 326 | |
dc9eb698 | 327 | rc = audit_do_config_change("audit_enabled", &audit_enabled, state); |
b593d384 EP |
328 | if (!rc) |
329 | audit_ever_enabled |= !!state; | |
330 | ||
331 | return rc; | |
1da177e4 LT |
332 | } |
333 | ||
dc9eb698 | 334 | static int audit_set_failure(int state) |
1da177e4 | 335 | { |
1da177e4 LT |
336 | if (state != AUDIT_FAIL_SILENT |
337 | && state != AUDIT_FAIL_PRINTK | |
338 | && state != AUDIT_FAIL_PANIC) | |
339 | return -EINVAL; | |
ce29b682 | 340 | |
dc9eb698 | 341 | return audit_do_config_change("audit_failure", &audit_failure, state); |
1da177e4 LT |
342 | } |
343 | ||
f3d357b0 EP |
344 | /* |
345 | * Queue skbs to be sent to auditd when/if it comes back. These skbs should | |
346 | * already have been sent via prink/syslog and so if these messages are dropped | |
347 | * it is not a huge concern since we already passed the audit_log_lost() | |
348 | * notification and stuff. This is just nice to get audit messages during | |
349 | * boot before auditd is running or messages generated while auditd is stopped. | |
350 | * This only holds messages is audit_default is set, aka booting with audit=1 | |
351 | * or building your kernel that way. | |
352 | */ | |
353 | static void audit_hold_skb(struct sk_buff *skb) | |
354 | { | |
355 | if (audit_default && | |
356 | skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit) | |
357 | skb_queue_tail(&audit_skb_hold_queue, skb); | |
358 | else | |
359 | kfree_skb(skb); | |
360 | } | |
361 | ||
038cbcf6 EP |
362 | /* |
363 | * For one reason or another this nlh isn't getting delivered to the userspace | |
364 | * audit daemon, just send it to printk. | |
365 | */ | |
366 | static void audit_printk_skb(struct sk_buff *skb) | |
367 | { | |
368 | struct nlmsghdr *nlh = nlmsg_hdr(skb); | |
c64e66c6 | 369 | char *data = nlmsg_data(nlh); |
038cbcf6 EP |
370 | |
371 | if (nlh->nlmsg_type != AUDIT_EOE) { | |
372 | if (printk_ratelimit()) | |
373 | printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, data); | |
374 | else | |
375 | audit_log_lost("printk limit exceeded\n"); | |
376 | } | |
377 | ||
378 | audit_hold_skb(skb); | |
379 | } | |
380 | ||
f3d357b0 EP |
381 | static void kauditd_send_skb(struct sk_buff *skb) |
382 | { | |
383 | int err; | |
384 | /* take a reference in case we can't send it and we want to hold it */ | |
385 | skb_get(skb); | |
15e47304 | 386 | err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0); |
f3d357b0 | 387 | if (err < 0) { |
c9404c9c | 388 | BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */ |
f3d357b0 | 389 | printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid); |
9db3b9bc | 390 | audit_log_lost("auditd disappeared\n"); |
f3d357b0 EP |
391 | audit_pid = 0; |
392 | /* we might get lucky and get this in the next auditd */ | |
393 | audit_hold_skb(skb); | |
394 | } else | |
395 | /* drop the extra reference if sent ok */ | |
70d4bf6d | 396 | consume_skb(skb); |
f3d357b0 EP |
397 | } |
398 | ||
b551d1d9 RGB |
399 | /* |
400 | * flush_hold_queue - empty the hold queue if auditd appears | |
401 | * | |
402 | * If auditd just started, drain the queue of messages already | |
403 | * sent to syslog/printk. Remember loss here is ok. We already | |
404 | * called audit_log_lost() if it didn't go out normally. so the | |
405 | * race between the skb_dequeue and the next check for audit_pid | |
406 | * doesn't matter. | |
407 | * | |
408 | * If you ever find kauditd to be too slow we can get a perf win | |
409 | * by doing our own locking and keeping better track if there | |
410 | * are messages in this queue. I don't see the need now, but | |
411 | * in 5 years when I want to play with this again I'll see this | |
412 | * note and still have no friggin idea what i'm thinking today. | |
413 | */ | |
414 | static void flush_hold_queue(void) | |
415 | { | |
416 | struct sk_buff *skb; | |
417 | ||
418 | if (!audit_default || !audit_pid) | |
419 | return; | |
420 | ||
421 | skb = skb_dequeue(&audit_skb_hold_queue); | |
422 | if (likely(!skb)) | |
423 | return; | |
424 | ||
425 | while (skb && audit_pid) { | |
426 | kauditd_send_skb(skb); | |
427 | skb = skb_dequeue(&audit_skb_hold_queue); | |
428 | } | |
429 | ||
430 | /* | |
431 | * if auditd just disappeared but we | |
432 | * dequeued an skb we need to drop ref | |
433 | */ | |
434 | if (skb) | |
435 | consume_skb(skb); | |
436 | } | |
437 | ||
97a41e26 | 438 | static int kauditd_thread(void *dummy) |
b7d11258 | 439 | { |
83144186 | 440 | set_freezable(); |
4899b8b1 | 441 | while (!kthread_should_stop()) { |
3320c513 RGB |
442 | struct sk_buff *skb; |
443 | DECLARE_WAITQUEUE(wait, current); | |
444 | ||
b551d1d9 | 445 | flush_hold_queue(); |
f3d357b0 | 446 | |
b7d11258 | 447 | skb = skb_dequeue(&audit_skb_queue); |
9ad9ad38 | 448 | wake_up(&audit_backlog_wait); |
b7d11258 | 449 | if (skb) { |
f3d357b0 EP |
450 | if (audit_pid) |
451 | kauditd_send_skb(skb); | |
038cbcf6 EP |
452 | else |
453 | audit_printk_skb(skb); | |
3320c513 RGB |
454 | continue; |
455 | } | |
456 | set_current_state(TASK_INTERRUPTIBLE); | |
457 | add_wait_queue(&kauditd_wait, &wait); | |
b7d11258 | 458 | |
3320c513 RGB |
459 | if (!skb_queue_len(&audit_skb_queue)) { |
460 | try_to_freeze(); | |
461 | schedule(); | |
b7d11258 | 462 | } |
3320c513 RGB |
463 | |
464 | __set_current_state(TASK_RUNNING); | |
465 | remove_wait_queue(&kauditd_wait, &wait); | |
b7d11258 | 466 | } |
4899b8b1 | 467 | return 0; |
b7d11258 DW |
468 | } |
469 | ||
9044e6bc AV |
470 | int audit_send_list(void *_dest) |
471 | { | |
472 | struct audit_netlink_list *dest = _dest; | |
473 | int pid = dest->pid; | |
474 | struct sk_buff *skb; | |
475 | ||
476 | /* wait for parent to finish and send an ACK */ | |
f368c07d AG |
477 | mutex_lock(&audit_cmd_mutex); |
478 | mutex_unlock(&audit_cmd_mutex); | |
9044e6bc AV |
479 | |
480 | while ((skb = __skb_dequeue(&dest->q)) != NULL) | |
481 | netlink_unicast(audit_sock, skb, pid, 0); | |
482 | ||
483 | kfree(dest); | |
484 | ||
485 | return 0; | |
486 | } | |
487 | ||
488 | struct sk_buff *audit_make_reply(int pid, int seq, int type, int done, | |
b8800aa5 | 489 | int multi, const void *payload, int size) |
9044e6bc AV |
490 | { |
491 | struct sk_buff *skb; | |
492 | struct nlmsghdr *nlh; | |
9044e6bc AV |
493 | void *data; |
494 | int flags = multi ? NLM_F_MULTI : 0; | |
495 | int t = done ? NLMSG_DONE : type; | |
496 | ||
ee080e6c | 497 | skb = nlmsg_new(size, GFP_KERNEL); |
9044e6bc AV |
498 | if (!skb) |
499 | return NULL; | |
500 | ||
c64e66c6 DM |
501 | nlh = nlmsg_put(skb, pid, seq, t, size, flags); |
502 | if (!nlh) | |
503 | goto out_kfree_skb; | |
504 | data = nlmsg_data(nlh); | |
9044e6bc AV |
505 | memcpy(data, payload, size); |
506 | return skb; | |
507 | ||
c64e66c6 DM |
508 | out_kfree_skb: |
509 | kfree_skb(skb); | |
9044e6bc AV |
510 | return NULL; |
511 | } | |
512 | ||
f09ac9db EP |
513 | static int audit_send_reply_thread(void *arg) |
514 | { | |
515 | struct audit_reply *reply = (struct audit_reply *)arg; | |
516 | ||
517 | mutex_lock(&audit_cmd_mutex); | |
518 | mutex_unlock(&audit_cmd_mutex); | |
519 | ||
520 | /* Ignore failure. It'll only happen if the sender goes away, | |
521 | because our timeout is set to infinite. */ | |
522 | netlink_unicast(audit_sock, reply->skb, reply->pid, 0); | |
523 | kfree(reply); | |
524 | return 0; | |
525 | } | |
b0dd25a8 RD |
526 | /** |
527 | * audit_send_reply - send an audit reply message via netlink | |
528 | * @pid: process id to send reply to | |
529 | * @seq: sequence number | |
530 | * @type: audit message type | |
531 | * @done: done (last) flag | |
532 | * @multi: multi-part message flag | |
533 | * @payload: payload data | |
534 | * @size: payload size | |
535 | * | |
536 | * Allocates an skb, builds the netlink message, and sends it to the pid. | |
537 | * No failure notifications. | |
538 | */ | |
b8800aa5 SH |
539 | static void audit_send_reply(int pid, int seq, int type, int done, int multi, |
540 | const void *payload, int size) | |
1da177e4 | 541 | { |
f09ac9db EP |
542 | struct sk_buff *skb; |
543 | struct task_struct *tsk; | |
544 | struct audit_reply *reply = kmalloc(sizeof(struct audit_reply), | |
545 | GFP_KERNEL); | |
546 | ||
547 | if (!reply) | |
548 | return; | |
549 | ||
9044e6bc | 550 | skb = audit_make_reply(pid, seq, type, done, multi, payload, size); |
1da177e4 | 551 | if (!skb) |
fcaf1eb8 | 552 | goto out; |
f09ac9db EP |
553 | |
554 | reply->pid = pid; | |
555 | reply->skb = skb; | |
556 | ||
557 | tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply"); | |
fcaf1eb8 AM |
558 | if (!IS_ERR(tsk)) |
559 | return; | |
560 | kfree_skb(skb); | |
561 | out: | |
562 | kfree(reply); | |
1da177e4 LT |
563 | } |
564 | ||
565 | /* | |
566 | * Check for appropriate CAP_AUDIT_ capabilities on incoming audit | |
567 | * control messages. | |
568 | */ | |
c7bdb545 | 569 | static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type) |
1da177e4 LT |
570 | { |
571 | int err = 0; | |
572 | ||
34e36d8e EB |
573 | /* Only support the initial namespaces for now. */ |
574 | if ((current_user_ns() != &init_user_ns) || | |
575 | (task_active_pid_ns(current) != &init_pid_ns)) | |
576 | return -EPERM; | |
577 | ||
1da177e4 | 578 | switch (msg_type) { |
1da177e4 | 579 | case AUDIT_LIST: |
1da177e4 LT |
580 | case AUDIT_ADD: |
581 | case AUDIT_DEL: | |
18900909 EP |
582 | return -EOPNOTSUPP; |
583 | case AUDIT_GET: | |
584 | case AUDIT_SET: | |
585 | case AUDIT_LIST_RULES: | |
586 | case AUDIT_ADD_RULE: | |
93315ed6 | 587 | case AUDIT_DEL_RULE: |
c2f0c7c3 | 588 | case AUDIT_SIGNAL_INFO: |
522ed776 MT |
589 | case AUDIT_TTY_GET: |
590 | case AUDIT_TTY_SET: | |
74c3cbe3 AV |
591 | case AUDIT_TRIM: |
592 | case AUDIT_MAKE_EQUIV: | |
fd778461 | 593 | if (!capable(CAP_AUDIT_CONTROL)) |
1da177e4 LT |
594 | err = -EPERM; |
595 | break; | |
05474106 | 596 | case AUDIT_USER: |
039b6b3e RD |
597 | case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG: |
598 | case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2: | |
fd778461 | 599 | if (!capable(CAP_AUDIT_WRITE)) |
1da177e4 LT |
600 | err = -EPERM; |
601 | break; | |
602 | default: /* bad msg */ | |
603 | err = -EINVAL; | |
604 | } | |
605 | ||
606 | return err; | |
607 | } | |
608 | ||
dc9eb698 | 609 | static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type) |
50397bd1 EP |
610 | { |
611 | int rc = 0; | |
dc9eb698 | 612 | uid_t uid = from_kuid(&init_user_ns, current_uid()); |
50397bd1 EP |
613 | |
614 | if (!audit_enabled) { | |
615 | *ab = NULL; | |
616 | return rc; | |
617 | } | |
618 | ||
619 | *ab = audit_log_start(NULL, GFP_KERNEL, msg_type); | |
0644ec0c KC |
620 | if (unlikely(!*ab)) |
621 | return rc; | |
4d3fb709 EP |
622 | audit_log_format(*ab, "pid=%d uid=%u", task_tgid_vnr(current), uid); |
623 | audit_log_session_info(*ab); | |
b122c376 | 624 | audit_log_task_context(*ab); |
50397bd1 EP |
625 | |
626 | return rc; | |
627 | } | |
628 | ||
1da177e4 LT |
629 | static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) |
630 | { | |
dc9eb698 | 631 | u32 seq; |
1da177e4 LT |
632 | void *data; |
633 | struct audit_status *status_get, status_set; | |
634 | int err; | |
c0404993 | 635 | struct audit_buffer *ab; |
1da177e4 | 636 | u16 msg_type = nlh->nlmsg_type; |
e1396065 | 637 | struct audit_sig_info *sig_data; |
50397bd1 | 638 | char *ctx = NULL; |
e1396065 | 639 | u32 len; |
1da177e4 | 640 | |
c7bdb545 | 641 | err = audit_netlink_ok(skb, msg_type); |
1da177e4 LT |
642 | if (err) |
643 | return err; | |
644 | ||
1da177e4 | 645 | seq = nlh->nlmsg_seq; |
c64e66c6 | 646 | data = nlmsg_data(nlh); |
1da177e4 LT |
647 | |
648 | switch (msg_type) { | |
649 | case AUDIT_GET: | |
650 | status_set.enabled = audit_enabled; | |
651 | status_set.failure = audit_failure; | |
652 | status_set.pid = audit_pid; | |
653 | status_set.rate_limit = audit_rate_limit; | |
654 | status_set.backlog_limit = audit_backlog_limit; | |
655 | status_set.lost = atomic_read(&audit_lost); | |
b7d11258 | 656 | status_set.backlog = skb_queue_len(&audit_skb_queue); |
15e47304 | 657 | audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0, |
1da177e4 LT |
658 | &status_set, sizeof(status_set)); |
659 | break; | |
660 | case AUDIT_SET: | |
661 | if (nlh->nlmsg_len < sizeof(struct audit_status)) | |
662 | return -EINVAL; | |
663 | status_get = (struct audit_status *)data; | |
664 | if (status_get->mask & AUDIT_STATUS_ENABLED) { | |
dc9eb698 | 665 | err = audit_set_enabled(status_get->enabled); |
20c6aaa3 | 666 | if (err < 0) |
667 | return err; | |
1da177e4 LT |
668 | } |
669 | if (status_get->mask & AUDIT_STATUS_FAILURE) { | |
dc9eb698 | 670 | err = audit_set_failure(status_get->failure); |
20c6aaa3 | 671 | if (err < 0) |
672 | return err; | |
1da177e4 LT |
673 | } |
674 | if (status_get->mask & AUDIT_STATUS_PID) { | |
1a6b9f23 EP |
675 | int new_pid = status_get->pid; |
676 | ||
677 | if (audit_enabled != AUDIT_OFF) | |
dc9eb698 | 678 | audit_log_config_change("audit_pid", new_pid, audit_pid, 1); |
1a6b9f23 | 679 | audit_pid = new_pid; |
15e47304 | 680 | audit_nlk_portid = NETLINK_CB(skb).portid; |
1da177e4 | 681 | } |
20c6aaa3 | 682 | if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) { |
dc9eb698 | 683 | err = audit_set_rate_limit(status_get->rate_limit); |
20c6aaa3 | 684 | if (err < 0) |
685 | return err; | |
686 | } | |
1da177e4 | 687 | if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT) |
dc9eb698 | 688 | err = audit_set_backlog_limit(status_get->backlog_limit); |
1da177e4 | 689 | break; |
05474106 | 690 | case AUDIT_USER: |
039b6b3e RD |
691 | case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG: |
692 | case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2: | |
4a4cd633 DW |
693 | if (!audit_enabled && msg_type != AUDIT_USER_AVC) |
694 | return 0; | |
695 | ||
62062cf8 | 696 | err = audit_filter_user(msg_type); |
4a4cd633 DW |
697 | if (err == 1) { |
698 | err = 0; | |
522ed776 | 699 | if (msg_type == AUDIT_USER_TTY) { |
152f497b | 700 | err = tty_audit_push_current(); |
522ed776 MT |
701 | if (err) |
702 | break; | |
703 | } | |
dc9eb698 | 704 | audit_log_common_recv_msg(&ab, msg_type); |
50397bd1 EP |
705 | if (msg_type != AUDIT_USER_TTY) |
706 | audit_log_format(ab, " msg='%.1024s'", | |
707 | (char *)data); | |
708 | else { | |
709 | int size; | |
710 | ||
f7616102 | 711 | audit_log_format(ab, " data="); |
50397bd1 | 712 | size = nlmsg_len(nlh); |
55ad2f8d MT |
713 | if (size > 0 && |
714 | ((unsigned char *)data)[size - 1] == '\0') | |
715 | size--; | |
b556f8ad | 716 | audit_log_n_untrustedstring(ab, data, size); |
4a4cd633 | 717 | } |
aecdc33e | 718 | audit_set_pid(ab, NETLINK_CB(skb).portid); |
50397bd1 | 719 | audit_log_end(ab); |
0f45aa18 | 720 | } |
1da177e4 | 721 | break; |
93315ed6 AG |
722 | case AUDIT_ADD_RULE: |
723 | case AUDIT_DEL_RULE: | |
724 | if (nlmsg_len(nlh) < sizeof(struct audit_rule_data)) | |
725 | return -EINVAL; | |
1a6b9f23 | 726 | if (audit_enabled == AUDIT_LOCKED) { |
dc9eb698 EP |
727 | audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
728 | audit_log_format(ab, " audit_enabled=%d res=0", audit_enabled); | |
50397bd1 | 729 | audit_log_end(ab); |
6a01b07f SG |
730 | return -EPERM; |
731 | } | |
93315ed6 AG |
732 | /* fallthrough */ |
733 | case AUDIT_LIST_RULES: | |
15e47304 | 734 | err = audit_receive_filter(msg_type, NETLINK_CB(skb).portid, |
dc9eb698 | 735 | seq, data, nlmsg_len(nlh)); |
1da177e4 | 736 | break; |
74c3cbe3 AV |
737 | case AUDIT_TRIM: |
738 | audit_trim_trees(); | |
dc9eb698 | 739 | audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
74c3cbe3 AV |
740 | audit_log_format(ab, " op=trim res=1"); |
741 | audit_log_end(ab); | |
742 | break; | |
743 | case AUDIT_MAKE_EQUIV: { | |
744 | void *bufp = data; | |
745 | u32 sizes[2]; | |
7719e437 | 746 | size_t msglen = nlmsg_len(nlh); |
74c3cbe3 AV |
747 | char *old, *new; |
748 | ||
749 | err = -EINVAL; | |
7719e437 | 750 | if (msglen < 2 * sizeof(u32)) |
74c3cbe3 AV |
751 | break; |
752 | memcpy(sizes, bufp, 2 * sizeof(u32)); | |
753 | bufp += 2 * sizeof(u32); | |
7719e437 HH |
754 | msglen -= 2 * sizeof(u32); |
755 | old = audit_unpack_string(&bufp, &msglen, sizes[0]); | |
74c3cbe3 AV |
756 | if (IS_ERR(old)) { |
757 | err = PTR_ERR(old); | |
758 | break; | |
759 | } | |
7719e437 | 760 | new = audit_unpack_string(&bufp, &msglen, sizes[1]); |
74c3cbe3 AV |
761 | if (IS_ERR(new)) { |
762 | err = PTR_ERR(new); | |
763 | kfree(old); | |
764 | break; | |
765 | } | |
766 | /* OK, here comes... */ | |
767 | err = audit_tag_tree(old, new); | |
768 | ||
dc9eb698 | 769 | audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); |
50397bd1 | 770 | |
74c3cbe3 AV |
771 | audit_log_format(ab, " op=make_equiv old="); |
772 | audit_log_untrustedstring(ab, old); | |
773 | audit_log_format(ab, " new="); | |
774 | audit_log_untrustedstring(ab, new); | |
775 | audit_log_format(ab, " res=%d", !err); | |
776 | audit_log_end(ab); | |
777 | kfree(old); | |
778 | kfree(new); | |
779 | break; | |
780 | } | |
c2f0c7c3 | 781 | case AUDIT_SIGNAL_INFO: |
939cbf26 EP |
782 | len = 0; |
783 | if (audit_sig_sid) { | |
784 | err = security_secid_to_secctx(audit_sig_sid, &ctx, &len); | |
785 | if (err) | |
786 | return err; | |
787 | } | |
e1396065 AV |
788 | sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL); |
789 | if (!sig_data) { | |
939cbf26 EP |
790 | if (audit_sig_sid) |
791 | security_release_secctx(ctx, len); | |
e1396065 AV |
792 | return -ENOMEM; |
793 | } | |
cca080d9 | 794 | sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid); |
e1396065 | 795 | sig_data->pid = audit_sig_pid; |
939cbf26 EP |
796 | if (audit_sig_sid) { |
797 | memcpy(sig_data->ctx, ctx, len); | |
798 | security_release_secctx(ctx, len); | |
799 | } | |
15e47304 | 800 | audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_SIGNAL_INFO, |
e1396065 AV |
801 | 0, 0, sig_data, sizeof(*sig_data) + len); |
802 | kfree(sig_data); | |
c2f0c7c3 | 803 | break; |
522ed776 MT |
804 | case AUDIT_TTY_GET: { |
805 | struct audit_tty_status s; | |
8aa14b64 | 806 | struct task_struct *tsk = current; |
bde02ca8 | 807 | unsigned long flags; |
8aa14b64 | 808 | |
bde02ca8 | 809 | spin_lock_irqsave(&tsk->sighand->siglock, flags); |
8aa14b64 | 810 | s.enabled = tsk->signal->audit_tty != 0; |
bde02ca8 | 811 | spin_unlock_irqrestore(&tsk->sighand->siglock, flags); |
8aa14b64 | 812 | |
aecdc33e | 813 | audit_send_reply(NETLINK_CB(skb).portid, seq, |
8aa14b64 | 814 | AUDIT_TTY_GET, 0, 0, &s, sizeof(s)); |
522ed776 MT |
815 | break; |
816 | } | |
817 | case AUDIT_TTY_SET: { | |
818 | struct audit_tty_status *s; | |
8aa14b64 | 819 | struct task_struct *tsk = current; |
bde02ca8 | 820 | unsigned long flags; |
522ed776 MT |
821 | |
822 | if (nlh->nlmsg_len < sizeof(struct audit_tty_status)) | |
823 | return -EINVAL; | |
824 | s = data; | |
825 | if (s->enabled != 0 && s->enabled != 1) | |
826 | return -EINVAL; | |
8aa14b64 | 827 | |
bde02ca8 | 828 | spin_lock_irqsave(&tsk->sighand->siglock, flags); |
8aa14b64 | 829 | tsk->signal->audit_tty = s->enabled != 0; |
bde02ca8 | 830 | spin_unlock_irqrestore(&tsk->sighand->siglock, flags); |
522ed776 MT |
831 | break; |
832 | } | |
1da177e4 LT |
833 | default: |
834 | err = -EINVAL; | |
835 | break; | |
836 | } | |
837 | ||
838 | return err < 0 ? err : 0; | |
839 | } | |
840 | ||
b0dd25a8 | 841 | /* |
ea7ae60b EP |
842 | * Get message from skb. Each message is processed by audit_receive_msg. |
843 | * Malformed skbs with wrong length are discarded silently. | |
b0dd25a8 | 844 | */ |
2a0a6ebe | 845 | static void audit_receive_skb(struct sk_buff *skb) |
1da177e4 | 846 | { |
ea7ae60b EP |
847 | struct nlmsghdr *nlh; |
848 | /* | |
849 | * len MUST be signed for NLMSG_NEXT to be able to dec it below 0 | |
850 | * if the nlmsg_len was not aligned | |
851 | */ | |
852 | int len; | |
853 | int err; | |
854 | ||
855 | nlh = nlmsg_hdr(skb); | |
856 | len = skb->len; | |
857 | ||
858 | while (NLMSG_OK(nlh, len)) { | |
859 | err = audit_receive_msg(skb, nlh); | |
860 | /* if err or if this message says it wants a response */ | |
861 | if (err || (nlh->nlmsg_flags & NLM_F_ACK)) | |
1da177e4 | 862 | netlink_ack(skb, nlh, err); |
ea7ae60b EP |
863 | |
864 | nlh = NLMSG_NEXT(nlh, len); | |
1da177e4 | 865 | } |
1da177e4 LT |
866 | } |
867 | ||
868 | /* Receive messages from netlink socket. */ | |
cd40b7d3 | 869 | static void audit_receive(struct sk_buff *skb) |
1da177e4 | 870 | { |
f368c07d | 871 | mutex_lock(&audit_cmd_mutex); |
cd40b7d3 | 872 | audit_receive_skb(skb); |
f368c07d | 873 | mutex_unlock(&audit_cmd_mutex); |
1da177e4 LT |
874 | } |
875 | ||
1da177e4 LT |
876 | /* Initialize audit support at boot time. */ |
877 | static int __init audit_init(void) | |
878 | { | |
f368c07d | 879 | int i; |
a31f2d17 PNA |
880 | struct netlink_kernel_cfg cfg = { |
881 | .input = audit_receive, | |
882 | }; | |
f368c07d | 883 | |
a3f07114 EP |
884 | if (audit_initialized == AUDIT_DISABLED) |
885 | return 0; | |
886 | ||
1da177e4 LT |
887 | printk(KERN_INFO "audit: initializing netlink socket (%s)\n", |
888 | audit_default ? "enabled" : "disabled"); | |
9f00d977 | 889 | audit_sock = netlink_kernel_create(&init_net, NETLINK_AUDIT, &cfg); |
1da177e4 LT |
890 | if (!audit_sock) |
891 | audit_panic("cannot initialize netlink socket"); | |
71e1c784 AG |
892 | else |
893 | audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; | |
1da177e4 | 894 | |
6ff5e459 RGB |
895 | kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd"); |
896 | if (IS_ERR(kauditd_task)) | |
897 | return PTR_ERR(kauditd_task); | |
898 | ||
b7d11258 | 899 | skb_queue_head_init(&audit_skb_queue); |
f3d357b0 | 900 | skb_queue_head_init(&audit_skb_hold_queue); |
a3f07114 | 901 | audit_initialized = AUDIT_INITIALIZED; |
1da177e4 | 902 | audit_enabled = audit_default; |
b593d384 | 903 | audit_ever_enabled |= !!audit_default; |
3dc7e315 | 904 | |
9ad9ad38 | 905 | audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized"); |
f368c07d | 906 | |
f368c07d AG |
907 | for (i = 0; i < AUDIT_INODE_BUCKETS; i++) |
908 | INIT_LIST_HEAD(&audit_inode_hash[i]); | |
f368c07d | 909 | |
1da177e4 LT |
910 | return 0; |
911 | } | |
1da177e4 LT |
912 | __initcall(audit_init); |
913 | ||
914 | /* Process kernel command-line parameter at boot time. audit=0 or audit=1. */ | |
915 | static int __init audit_enable(char *str) | |
916 | { | |
917 | audit_default = !!simple_strtol(str, NULL, 0); | |
a3f07114 EP |
918 | if (!audit_default) |
919 | audit_initialized = AUDIT_DISABLED; | |
920 | ||
921 | printk(KERN_INFO "audit: %s", audit_default ? "enabled" : "disabled"); | |
922 | ||
923 | if (audit_initialized == AUDIT_INITIALIZED) { | |
1da177e4 | 924 | audit_enabled = audit_default; |
b593d384 | 925 | audit_ever_enabled |= !!audit_default; |
a3f07114 EP |
926 | } else if (audit_initialized == AUDIT_UNINITIALIZED) { |
927 | printk(" (after initialization)"); | |
928 | } else { | |
929 | printk(" (until reboot)"); | |
b593d384 | 930 | } |
a3f07114 EP |
931 | printk("\n"); |
932 | ||
9b41046c | 933 | return 1; |
1da177e4 LT |
934 | } |
935 | ||
936 | __setup("audit=", audit_enable); | |
937 | ||
16e1904e CW |
938 | static void audit_buffer_free(struct audit_buffer *ab) |
939 | { | |
940 | unsigned long flags; | |
941 | ||
8fc6115c CW |
942 | if (!ab) |
943 | return; | |
944 | ||
5ac52f33 CW |
945 | if (ab->skb) |
946 | kfree_skb(ab->skb); | |
b7d11258 | 947 | |
16e1904e | 948 | spin_lock_irqsave(&audit_freelist_lock, flags); |
5d136a01 | 949 | if (audit_freelist_count > AUDIT_MAXFREE) |
16e1904e | 950 | kfree(ab); |
5d136a01 SH |
951 | else { |
952 | audit_freelist_count++; | |
16e1904e | 953 | list_add(&ab->list, &audit_freelist); |
5d136a01 | 954 | } |
16e1904e CW |
955 | spin_unlock_irqrestore(&audit_freelist_lock, flags); |
956 | } | |
957 | ||
c0404993 | 958 | static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx, |
dd0fc66f | 959 | gfp_t gfp_mask, int type) |
16e1904e CW |
960 | { |
961 | unsigned long flags; | |
962 | struct audit_buffer *ab = NULL; | |
c0404993 | 963 | struct nlmsghdr *nlh; |
16e1904e CW |
964 | |
965 | spin_lock_irqsave(&audit_freelist_lock, flags); | |
966 | if (!list_empty(&audit_freelist)) { | |
967 | ab = list_entry(audit_freelist.next, | |
968 | struct audit_buffer, list); | |
969 | list_del(&ab->list); | |
970 | --audit_freelist_count; | |
971 | } | |
972 | spin_unlock_irqrestore(&audit_freelist_lock, flags); | |
973 | ||
974 | if (!ab) { | |
4332bdd3 | 975 | ab = kmalloc(sizeof(*ab), gfp_mask); |
16e1904e | 976 | if (!ab) |
8fc6115c | 977 | goto err; |
16e1904e | 978 | } |
8fc6115c | 979 | |
b7d11258 | 980 | ab->ctx = ctx; |
9ad9ad38 | 981 | ab->gfp_mask = gfp_mask; |
ee080e6c EP |
982 | |
983 | ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask); | |
984 | if (!ab->skb) | |
c64e66c6 | 985 | goto err; |
ee080e6c | 986 | |
c64e66c6 DM |
987 | nlh = nlmsg_put(ab->skb, 0, 0, type, 0, 0); |
988 | if (!nlh) | |
989 | goto out_kfree_skb; | |
ee080e6c | 990 | |
16e1904e | 991 | return ab; |
ee080e6c | 992 | |
c64e66c6 | 993 | out_kfree_skb: |
ee080e6c EP |
994 | kfree_skb(ab->skb); |
995 | ab->skb = NULL; | |
8fc6115c CW |
996 | err: |
997 | audit_buffer_free(ab); | |
998 | return NULL; | |
16e1904e | 999 | } |
1da177e4 | 1000 | |
b0dd25a8 RD |
1001 | /** |
1002 | * audit_serial - compute a serial number for the audit record | |
1003 | * | |
1004 | * Compute a serial number for the audit record. Audit records are | |
bfb4496e DW |
1005 | * written to user-space as soon as they are generated, so a complete |
1006 | * audit record may be written in several pieces. The timestamp of the | |
1007 | * record and this serial number are used by the user-space tools to | |
1008 | * determine which pieces belong to the same audit record. The | |
1009 | * (timestamp,serial) tuple is unique for each syscall and is live from | |
1010 | * syscall entry to syscall exit. | |
1011 | * | |
bfb4496e DW |
1012 | * NOTE: Another possibility is to store the formatted records off the |
1013 | * audit context (for those records that have a context), and emit them | |
1014 | * all at syscall exit. However, this could delay the reporting of | |
1015 | * significant errors until syscall exit (or never, if the system | |
b0dd25a8 RD |
1016 | * halts). |
1017 | */ | |
bfb4496e DW |
1018 | unsigned int audit_serial(void) |
1019 | { | |
34af946a | 1020 | static DEFINE_SPINLOCK(serial_lock); |
d5b454f2 DW |
1021 | static unsigned int serial = 0; |
1022 | ||
1023 | unsigned long flags; | |
1024 | unsigned int ret; | |
bfb4496e | 1025 | |
d5b454f2 | 1026 | spin_lock_irqsave(&serial_lock, flags); |
bfb4496e | 1027 | do { |
ce625a80 DW |
1028 | ret = ++serial; |
1029 | } while (unlikely(!ret)); | |
d5b454f2 | 1030 | spin_unlock_irqrestore(&serial_lock, flags); |
bfb4496e | 1031 | |
d5b454f2 | 1032 | return ret; |
bfb4496e DW |
1033 | } |
1034 | ||
5600b892 | 1035 | static inline void audit_get_stamp(struct audit_context *ctx, |
bfb4496e DW |
1036 | struct timespec *t, unsigned int *serial) |
1037 | { | |
48887e63 | 1038 | if (!ctx || !auditsc_get_stamp(ctx, t, serial)) { |
bfb4496e DW |
1039 | *t = CURRENT_TIME; |
1040 | *serial = audit_serial(); | |
1041 | } | |
1042 | } | |
1043 | ||
82919919 AM |
1044 | /* |
1045 | * Wait for auditd to drain the queue a little | |
1046 | */ | |
1047 | static void wait_for_auditd(unsigned long sleep_time) | |
1048 | { | |
1049 | DECLARE_WAITQUEUE(wait, current); | |
1050 | set_current_state(TASK_INTERRUPTIBLE); | |
1051 | add_wait_queue(&audit_backlog_wait, &wait); | |
1052 | ||
1053 | if (audit_backlog_limit && | |
1054 | skb_queue_len(&audit_skb_queue) > audit_backlog_limit) | |
1055 | schedule_timeout(sleep_time); | |
1056 | ||
1057 | __set_current_state(TASK_RUNNING); | |
1058 | remove_wait_queue(&audit_backlog_wait, &wait); | |
1059 | } | |
1060 | ||
1da177e4 LT |
1061 | /* Obtain an audit buffer. This routine does locking to obtain the |
1062 | * audit buffer, but then no locking is required for calls to | |
1063 | * audit_log_*format. If the tsk is a task that is currently in a | |
1064 | * syscall, then the syscall is marked as auditable and an audit record | |
1065 | * will be written at syscall exit. If there is no associated task, tsk | |
1066 | * should be NULL. */ | |
9ad9ad38 | 1067 | |
b0dd25a8 RD |
1068 | /** |
1069 | * audit_log_start - obtain an audit buffer | |
1070 | * @ctx: audit_context (may be NULL) | |
1071 | * @gfp_mask: type of allocation | |
1072 | * @type: audit message type | |
1073 | * | |
1074 | * Returns audit_buffer pointer on success or NULL on error. | |
1075 | * | |
1076 | * Obtain an audit buffer. This routine does locking to obtain the | |
1077 | * audit buffer, but then no locking is required for calls to | |
1078 | * audit_log_*format. If the task (ctx) is a task that is currently in a | |
1079 | * syscall, then the syscall is marked as auditable and an audit record | |
1080 | * will be written at syscall exit. If there is no associated task, then | |
1081 | * task context (ctx) should be NULL. | |
1082 | */ | |
9796fdd8 | 1083 | struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, |
9ad9ad38 | 1084 | int type) |
1da177e4 LT |
1085 | { |
1086 | struct audit_buffer *ab = NULL; | |
1da177e4 | 1087 | struct timespec t; |
ef00be05 | 1088 | unsigned int uninitialized_var(serial); |
9ad9ad38 | 1089 | int reserve; |
ac4cec44 | 1090 | unsigned long timeout_start = jiffies; |
1da177e4 | 1091 | |
a3f07114 | 1092 | if (audit_initialized != AUDIT_INITIALIZED) |
1da177e4 LT |
1093 | return NULL; |
1094 | ||
c8edc80c DK |
1095 | if (unlikely(audit_filter_type(type))) |
1096 | return NULL; | |
1097 | ||
9ad9ad38 DW |
1098 | if (gfp_mask & __GFP_WAIT) |
1099 | reserve = 0; | |
1100 | else | |
5600b892 | 1101 | reserve = 5; /* Allow atomic callers to go up to five |
9ad9ad38 DW |
1102 | entries over the normal backlog limit */ |
1103 | ||
1104 | while (audit_backlog_limit | |
1105 | && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) { | |
82919919 AM |
1106 | if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) { |
1107 | unsigned long sleep_time; | |
9ad9ad38 | 1108 | |
82919919 AM |
1109 | sleep_time = timeout_start + audit_backlog_wait_time - |
1110 | jiffies; | |
1111 | if ((long)sleep_time > 0) | |
1112 | wait_for_auditd(sleep_time); | |
ac4cec44 | 1113 | continue; |
9ad9ad38 | 1114 | } |
320f1b1e | 1115 | if (audit_rate_check() && printk_ratelimit()) |
fb19b4c6 DW |
1116 | printk(KERN_WARNING |
1117 | "audit: audit_backlog=%d > " | |
1118 | "audit_backlog_limit=%d\n", | |
1119 | skb_queue_len(&audit_skb_queue), | |
1120 | audit_backlog_limit); | |
1121 | audit_log_lost("backlog limit exceeded"); | |
ac4cec44 DW |
1122 | audit_backlog_wait_time = audit_backlog_wait_overflow; |
1123 | wake_up(&audit_backlog_wait); | |
fb19b4c6 DW |
1124 | return NULL; |
1125 | } | |
1126 | ||
9ad9ad38 | 1127 | ab = audit_buffer_alloc(ctx, gfp_mask, type); |
1da177e4 LT |
1128 | if (!ab) { |
1129 | audit_log_lost("out of memory in audit_log_start"); | |
1130 | return NULL; | |
1131 | } | |
1132 | ||
bfb4496e | 1133 | audit_get_stamp(ab->ctx, &t, &serial); |
197c69c6 | 1134 | |
1da177e4 LT |
1135 | audit_log_format(ab, "audit(%lu.%03lu:%u): ", |
1136 | t.tv_sec, t.tv_nsec/1000000, serial); | |
1137 | return ab; | |
1138 | } | |
1139 | ||
8fc6115c | 1140 | /** |
5ac52f33 | 1141 | * audit_expand - expand skb in the audit buffer |
8fc6115c | 1142 | * @ab: audit_buffer |
b0dd25a8 | 1143 | * @extra: space to add at tail of the skb |
8fc6115c CW |
1144 | * |
1145 | * Returns 0 (no space) on failed expansion, or available space if | |
1146 | * successful. | |
1147 | */ | |
e3b926b4 | 1148 | static inline int audit_expand(struct audit_buffer *ab, int extra) |
8fc6115c | 1149 | { |
5ac52f33 | 1150 | struct sk_buff *skb = ab->skb; |
406a1d86 HX |
1151 | int oldtail = skb_tailroom(skb); |
1152 | int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask); | |
1153 | int newtail = skb_tailroom(skb); | |
1154 | ||
5ac52f33 CW |
1155 | if (ret < 0) { |
1156 | audit_log_lost("out of memory in audit_expand"); | |
8fc6115c | 1157 | return 0; |
5ac52f33 | 1158 | } |
406a1d86 HX |
1159 | |
1160 | skb->truesize += newtail - oldtail; | |
1161 | return newtail; | |
8fc6115c | 1162 | } |
1da177e4 | 1163 | |
b0dd25a8 RD |
1164 | /* |
1165 | * Format an audit message into the audit buffer. If there isn't enough | |
1da177e4 LT |
1166 | * room in the audit buffer, more room will be allocated and vsnprint |
1167 | * will be called a second time. Currently, we assume that a printk | |
b0dd25a8 RD |
1168 | * can't format message larger than 1024 bytes, so we don't either. |
1169 | */ | |
1da177e4 LT |
1170 | static void audit_log_vformat(struct audit_buffer *ab, const char *fmt, |
1171 | va_list args) | |
1172 | { | |
1173 | int len, avail; | |
5ac52f33 | 1174 | struct sk_buff *skb; |
eecb0a73 | 1175 | va_list args2; |
1da177e4 LT |
1176 | |
1177 | if (!ab) | |
1178 | return; | |
1179 | ||
5ac52f33 CW |
1180 | BUG_ON(!ab->skb); |
1181 | skb = ab->skb; | |
1182 | avail = skb_tailroom(skb); | |
1183 | if (avail == 0) { | |
e3b926b4 | 1184 | avail = audit_expand(ab, AUDIT_BUFSIZ); |
8fc6115c CW |
1185 | if (!avail) |
1186 | goto out; | |
1da177e4 | 1187 | } |
eecb0a73 | 1188 | va_copy(args2, args); |
27a884dc | 1189 | len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args); |
1da177e4 LT |
1190 | if (len >= avail) { |
1191 | /* The printk buffer is 1024 bytes long, so if we get | |
1192 | * here and AUDIT_BUFSIZ is at least 1024, then we can | |
1193 | * log everything that printk could have logged. */ | |
b0dd25a8 RD |
1194 | avail = audit_expand(ab, |
1195 | max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail)); | |
8fc6115c | 1196 | if (!avail) |
a0e86bd4 | 1197 | goto out_va_end; |
27a884dc | 1198 | len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2); |
1da177e4 | 1199 | } |
168b7173 SG |
1200 | if (len > 0) |
1201 | skb_put(skb, len); | |
a0e86bd4 JJ |
1202 | out_va_end: |
1203 | va_end(args2); | |
8fc6115c CW |
1204 | out: |
1205 | return; | |
1da177e4 LT |
1206 | } |
1207 | ||
b0dd25a8 RD |
1208 | /** |
1209 | * audit_log_format - format a message into the audit buffer. | |
1210 | * @ab: audit_buffer | |
1211 | * @fmt: format string | |
1212 | * @...: optional parameters matching @fmt string | |
1213 | * | |
1214 | * All the work is done in audit_log_vformat. | |
1215 | */ | |
1da177e4 LT |
1216 | void audit_log_format(struct audit_buffer *ab, const char *fmt, ...) |
1217 | { | |
1218 | va_list args; | |
1219 | ||
1220 | if (!ab) | |
1221 | return; | |
1222 | va_start(args, fmt); | |
1223 | audit_log_vformat(ab, fmt, args); | |
1224 | va_end(args); | |
1225 | } | |
1226 | ||
b0dd25a8 RD |
1227 | /** |
1228 | * audit_log_hex - convert a buffer to hex and append it to the audit skb | |
1229 | * @ab: the audit_buffer | |
1230 | * @buf: buffer to convert to hex | |
1231 | * @len: length of @buf to be converted | |
1232 | * | |
1233 | * No return value; failure to expand is silently ignored. | |
1234 | * | |
1235 | * This function will take the passed buf and convert it into a string of | |
1236 | * ascii hex digits. The new string is placed onto the skb. | |
1237 | */ | |
b556f8ad | 1238 | void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf, |
168b7173 | 1239 | size_t len) |
83c7d091 | 1240 | { |
168b7173 SG |
1241 | int i, avail, new_len; |
1242 | unsigned char *ptr; | |
1243 | struct sk_buff *skb; | |
1244 | static const unsigned char *hex = "0123456789ABCDEF"; | |
1245 | ||
8ef2d304 AG |
1246 | if (!ab) |
1247 | return; | |
1248 | ||
168b7173 SG |
1249 | BUG_ON(!ab->skb); |
1250 | skb = ab->skb; | |
1251 | avail = skb_tailroom(skb); | |
1252 | new_len = len<<1; | |
1253 | if (new_len >= avail) { | |
1254 | /* Round the buffer request up to the next multiple */ | |
1255 | new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1); | |
1256 | avail = audit_expand(ab, new_len); | |
1257 | if (!avail) | |
1258 | return; | |
1259 | } | |
83c7d091 | 1260 | |
27a884dc | 1261 | ptr = skb_tail_pointer(skb); |
168b7173 SG |
1262 | for (i=0; i<len; i++) { |
1263 | *ptr++ = hex[(buf[i] & 0xF0)>>4]; /* Upper nibble */ | |
1264 | *ptr++ = hex[buf[i] & 0x0F]; /* Lower nibble */ | |
1265 | } | |
1266 | *ptr = 0; | |
1267 | skb_put(skb, len << 1); /* new string is twice the old string */ | |
83c7d091 | 1268 | } |
1269 | ||
9c937dcc AG |
1270 | /* |
1271 | * Format a string of no more than slen characters into the audit buffer, | |
1272 | * enclosed in quote marks. | |
1273 | */ | |
b556f8ad EP |
1274 | void audit_log_n_string(struct audit_buffer *ab, const char *string, |
1275 | size_t slen) | |
9c937dcc AG |
1276 | { |
1277 | int avail, new_len; | |
1278 | unsigned char *ptr; | |
1279 | struct sk_buff *skb; | |
1280 | ||
8ef2d304 AG |
1281 | if (!ab) |
1282 | return; | |
1283 | ||
9c937dcc AG |
1284 | BUG_ON(!ab->skb); |
1285 | skb = ab->skb; | |
1286 | avail = skb_tailroom(skb); | |
1287 | new_len = slen + 3; /* enclosing quotes + null terminator */ | |
1288 | if (new_len > avail) { | |
1289 | avail = audit_expand(ab, new_len); | |
1290 | if (!avail) | |
1291 | return; | |
1292 | } | |
27a884dc | 1293 | ptr = skb_tail_pointer(skb); |
9c937dcc AG |
1294 | *ptr++ = '"'; |
1295 | memcpy(ptr, string, slen); | |
1296 | ptr += slen; | |
1297 | *ptr++ = '"'; | |
1298 | *ptr = 0; | |
1299 | skb_put(skb, slen + 2); /* don't include null terminator */ | |
1300 | } | |
1301 | ||
de6bbd1d EP |
1302 | /** |
1303 | * audit_string_contains_control - does a string need to be logged in hex | |
f706d5d2 DJ |
1304 | * @string: string to be checked |
1305 | * @len: max length of the string to check | |
de6bbd1d EP |
1306 | */ |
1307 | int audit_string_contains_control(const char *string, size_t len) | |
1308 | { | |
1309 | const unsigned char *p; | |
b3897f56 | 1310 | for (p = string; p < (const unsigned char *)string + len; p++) { |
1d6c9649 | 1311 | if (*p == '"' || *p < 0x21 || *p > 0x7e) |
de6bbd1d EP |
1312 | return 1; |
1313 | } | |
1314 | return 0; | |
1315 | } | |
1316 | ||
b0dd25a8 | 1317 | /** |
522ed776 | 1318 | * audit_log_n_untrustedstring - log a string that may contain random characters |
b0dd25a8 | 1319 | * @ab: audit_buffer |
f706d5d2 | 1320 | * @len: length of string (not including trailing null) |
b0dd25a8 RD |
1321 | * @string: string to be logged |
1322 | * | |
1323 | * This code will escape a string that is passed to it if the string | |
1324 | * contains a control character, unprintable character, double quote mark, | |
168b7173 | 1325 | * or a space. Unescaped strings will start and end with a double quote mark. |
b0dd25a8 | 1326 | * Strings that are escaped are printed in hex (2 digits per char). |
9c937dcc AG |
1327 | * |
1328 | * The caller specifies the number of characters in the string to log, which may | |
1329 | * or may not be the entire string. | |
b0dd25a8 | 1330 | */ |
b556f8ad EP |
1331 | void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string, |
1332 | size_t len) | |
83c7d091 | 1333 | { |
de6bbd1d | 1334 | if (audit_string_contains_control(string, len)) |
b556f8ad | 1335 | audit_log_n_hex(ab, string, len); |
de6bbd1d | 1336 | else |
b556f8ad | 1337 | audit_log_n_string(ab, string, len); |
83c7d091 | 1338 | } |
1339 | ||
9c937dcc | 1340 | /** |
522ed776 | 1341 | * audit_log_untrustedstring - log a string that may contain random characters |
9c937dcc AG |
1342 | * @ab: audit_buffer |
1343 | * @string: string to be logged | |
1344 | * | |
522ed776 | 1345 | * Same as audit_log_n_untrustedstring(), except that strlen is used to |
9c937dcc AG |
1346 | * determine string length. |
1347 | */ | |
de6bbd1d | 1348 | void audit_log_untrustedstring(struct audit_buffer *ab, const char *string) |
9c937dcc | 1349 | { |
b556f8ad | 1350 | audit_log_n_untrustedstring(ab, string, strlen(string)); |
9c937dcc AG |
1351 | } |
1352 | ||
168b7173 | 1353 | /* This is a helper-function to print the escaped d_path */ |
1da177e4 | 1354 | void audit_log_d_path(struct audit_buffer *ab, const char *prefix, |
66b3fad3 | 1355 | const struct path *path) |
1da177e4 | 1356 | { |
44707fdf | 1357 | char *p, *pathname; |
1da177e4 | 1358 | |
8fc6115c | 1359 | if (prefix) |
c158a35c | 1360 | audit_log_format(ab, "%s", prefix); |
1da177e4 | 1361 | |
168b7173 | 1362 | /* We will allow 11 spaces for ' (deleted)' to be appended */ |
44707fdf JB |
1363 | pathname = kmalloc(PATH_MAX+11, ab->gfp_mask); |
1364 | if (!pathname) { | |
def57543 | 1365 | audit_log_string(ab, "<no_memory>"); |
168b7173 | 1366 | return; |
1da177e4 | 1367 | } |
cf28b486 | 1368 | p = d_path(path, pathname, PATH_MAX+11); |
168b7173 SG |
1369 | if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */ |
1370 | /* FIXME: can we save some information here? */ | |
def57543 | 1371 | audit_log_string(ab, "<too_long>"); |
5600b892 | 1372 | } else |
168b7173 | 1373 | audit_log_untrustedstring(ab, p); |
44707fdf | 1374 | kfree(pathname); |
1da177e4 LT |
1375 | } |
1376 | ||
4d3fb709 EP |
1377 | void audit_log_session_info(struct audit_buffer *ab) |
1378 | { | |
1379 | u32 sessionid = audit_get_sessionid(current); | |
1380 | uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current)); | |
1381 | ||
1382 | audit_log_format(ab, "auid=%u ses=%u\n", auid, sessionid); | |
1383 | } | |
1384 | ||
9d960985 EP |
1385 | void audit_log_key(struct audit_buffer *ab, char *key) |
1386 | { | |
1387 | audit_log_format(ab, " key="); | |
1388 | if (key) | |
1389 | audit_log_untrustedstring(ab, key); | |
1390 | else | |
1391 | audit_log_format(ab, "(null)"); | |
1392 | } | |
1393 | ||
a51d9eaa KC |
1394 | /** |
1395 | * audit_log_link_denied - report a link restriction denial | |
1396 | * @operation: specific link opreation | |
1397 | * @link: the path that triggered the restriction | |
1398 | */ | |
1399 | void audit_log_link_denied(const char *operation, struct path *link) | |
1400 | { | |
1401 | struct audit_buffer *ab; | |
1402 | ||
1403 | ab = audit_log_start(current->audit_context, GFP_KERNEL, | |
1404 | AUDIT_ANOM_LINK); | |
d1c7d97a SL |
1405 | if (!ab) |
1406 | return; | |
a51d9eaa KC |
1407 | audit_log_format(ab, "op=%s action=denied", operation); |
1408 | audit_log_format(ab, " pid=%d comm=", current->pid); | |
1409 | audit_log_untrustedstring(ab, current->comm); | |
1410 | audit_log_d_path(ab, " path=", link); | |
1411 | audit_log_format(ab, " dev="); | |
1412 | audit_log_untrustedstring(ab, link->dentry->d_inode->i_sb->s_id); | |
1413 | audit_log_format(ab, " ino=%lu", link->dentry->d_inode->i_ino); | |
1414 | audit_log_end(ab); | |
1415 | } | |
1416 | ||
b0dd25a8 RD |
1417 | /** |
1418 | * audit_log_end - end one audit record | |
1419 | * @ab: the audit_buffer | |
1420 | * | |
1421 | * The netlink_* functions cannot be called inside an irq context, so | |
1422 | * the audit buffer is placed on a queue and a tasklet is scheduled to | |
1da177e4 | 1423 | * remove them from the queue outside the irq context. May be called in |
b0dd25a8 RD |
1424 | * any context. |
1425 | */ | |
b7d11258 | 1426 | void audit_log_end(struct audit_buffer *ab) |
1da177e4 | 1427 | { |
1da177e4 LT |
1428 | if (!ab) |
1429 | return; | |
1430 | if (!audit_rate_check()) { | |
1431 | audit_log_lost("rate limit exceeded"); | |
1432 | } else { | |
8d07a67c | 1433 | struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); |
f3d357b0 EP |
1434 | nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0); |
1435 | ||
b7d11258 | 1436 | if (audit_pid) { |
b7d11258 | 1437 | skb_queue_tail(&audit_skb_queue, ab->skb); |
b7d11258 | 1438 | wake_up_interruptible(&kauditd_wait); |
f3d357b0 | 1439 | } else { |
038cbcf6 | 1440 | audit_printk_skb(ab->skb); |
b7d11258 | 1441 | } |
f3d357b0 | 1442 | ab->skb = NULL; |
1da177e4 | 1443 | } |
16e1904e | 1444 | audit_buffer_free(ab); |
1da177e4 LT |
1445 | } |
1446 | ||
b0dd25a8 RD |
1447 | /** |
1448 | * audit_log - Log an audit record | |
1449 | * @ctx: audit context | |
1450 | * @gfp_mask: type of allocation | |
1451 | * @type: audit message type | |
1452 | * @fmt: format string to use | |
1453 | * @...: variable parameters matching the format string | |
1454 | * | |
1455 | * This is a convenience function that calls audit_log_start, | |
1456 | * audit_log_vformat, and audit_log_end. It may be called | |
1457 | * in any context. | |
1458 | */ | |
5600b892 | 1459 | void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type, |
9ad9ad38 | 1460 | const char *fmt, ...) |
1da177e4 LT |
1461 | { |
1462 | struct audit_buffer *ab; | |
1463 | va_list args; | |
1464 | ||
9ad9ad38 | 1465 | ab = audit_log_start(ctx, gfp_mask, type); |
1da177e4 LT |
1466 | if (ab) { |
1467 | va_start(args, fmt); | |
1468 | audit_log_vformat(ab, fmt, args); | |
1469 | va_end(args); | |
1470 | audit_log_end(ab); | |
1471 | } | |
1472 | } | |
bf45da97 | 1473 | |
131ad62d MDF |
1474 | #ifdef CONFIG_SECURITY |
1475 | /** | |
1476 | * audit_log_secctx - Converts and logs SELinux context | |
1477 | * @ab: audit_buffer | |
1478 | * @secid: security number | |
1479 | * | |
1480 | * This is a helper function that calls security_secid_to_secctx to convert | |
1481 | * secid to secctx and then adds the (converted) SELinux context to the audit | |
1482 | * log by calling audit_log_format, thus also preventing leak of internal secid | |
1483 | * to userspace. If secid cannot be converted audit_panic is called. | |
1484 | */ | |
1485 | void audit_log_secctx(struct audit_buffer *ab, u32 secid) | |
1486 | { | |
1487 | u32 len; | |
1488 | char *secctx; | |
1489 | ||
1490 | if (security_secid_to_secctx(secid, &secctx, &len)) { | |
1491 | audit_panic("Cannot convert secid to context"); | |
1492 | } else { | |
1493 | audit_log_format(ab, " obj=%s", secctx); | |
1494 | security_release_secctx(secctx, len); | |
1495 | } | |
1496 | } | |
1497 | EXPORT_SYMBOL(audit_log_secctx); | |
1498 | #endif | |
1499 | ||
bf45da97 | 1500 | EXPORT_SYMBOL(audit_log_start); |
1501 | EXPORT_SYMBOL(audit_log_end); | |
1502 | EXPORT_SYMBOL(audit_log_format); | |
1503 | EXPORT_SYMBOL(audit_log); |