blob: a7b16086d36f7b863a19697eed4877b67226b197 [file] [log] [blame]
85c87212005-04-29 16:23:29 +01001/* audit.c -- Auditing support
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * Gateway between the kernel (e.g., selinux) and the user-space audit daemon.
3 * System-call specific features have moved to auditsc.c
4 *
Steve Grubb6a01b072007-01-19 14:39:55 -05005 * Copyright 2003-2007 Red Hat Inc., Durham, North Carolina.
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 * 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 *
Ahmed S. Darwishd7a96f32008-03-01 22:01:11 +020024 * Goals: 1) Integrate fully with Security Modules.
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 * 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 *
85c87212005-04-29 16:23:29 +010041 * Example user-space utilities: http://people.redhat.com/sgrubb/audit/
Linus Torvalds1da177e2005-04-16 15:20:36 -070042 */
43
44#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045#include <asm/types.h>
Alan Cox715b49e2006-01-18 17:44:07 -080046#include <asm/atomic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070047#include <linux/mm.h>
48#include <linux/module.h>
David Woodhouseb7d11252005-05-19 10:56:58 +010049#include <linux/err.h>
50#include <linux/kthread.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
52#include <linux/audit.h>
53
54#include <net/sock.h>
Amy Griffis93315ed2006-02-07 12:05:27 -050055#include <net/netlink.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070056#include <linux/skbuff.h>
57#include <linux/netlink.h>
Amy Griffisf368c07d2006-04-07 16:55:56 -040058#include <linux/inotify.h>
Nigel Cunningham7dfb7102006-12-06 20:34:23 -080059#include <linux/freezer.h>
Miloslav Trmac522ed772007-07-15 23:40:56 -070060#include <linux/tty.h>
Darrel Goeddel3dc7e312006-03-10 18:14:06 -060061
62#include "audit.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
64/* No auditing will take place until audit_initialized != 0.
65 * (Initialization happens after skb_init is called.) */
66static int audit_initialized;
67
Eric Paris1a6b9f22008-01-07 17:09:31 -050068#define AUDIT_OFF 0
69#define AUDIT_ON 1
70#define AUDIT_LOCKED 2
Linus Torvalds1da177e2005-04-16 15:20:36 -070071int audit_enabled;
Eric Parisb593d382008-01-08 17:38:31 -050072int audit_ever_enabled;
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74/* Default state when kernel boots without any parameters. */
75static int audit_default;
76
77/* If auditing cannot proceed, audit_failure selects what happens. */
78static int audit_failure = AUDIT_FAIL_PRINTK;
79
Pavel Emelyanov75c03712008-03-20 15:39:41 -070080/*
81 * If audit records are to be written to the netlink socket, audit_pid
82 * contains the pid of the auditd process and audit_nlk_pid contains
83 * the pid to use to send netlink messages to that process.
84 */
Steve Grubbc2f0c7c2005-05-06 12:38:39 +010085int audit_pid;
Pavel Emelyanov75c03712008-03-20 15:39:41 -070086static int audit_nlk_pid;
Linus Torvalds1da177e2005-04-16 15:20:36 -070087
Randy Dunlapb0dd25a2005-09-13 12:47:11 -070088/* If audit_rate_limit is non-zero, limit the rate of sending audit records
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 * to that number per second. This prevents DoS attacks, but results in
90 * audit records being dropped. */
91static int audit_rate_limit;
92
93/* Number of outstanding audit_buffers allowed. */
94static int audit_backlog_limit = 64;
David Woodhouseac4cec42005-07-02 14:08:48 +010095static int audit_backlog_wait_time = 60 * HZ;
96static int audit_backlog_wait_overflow = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070097
Steve Grubbc2f0c7c2005-05-06 12:38:39 +010098/* The identity of the user shutting down the audit system. */
99uid_t audit_sig_uid = -1;
100pid_t audit_sig_pid = -1;
Al Viroe1396062006-05-25 10:19:47 -0400101u32 audit_sig_sid = 0;
Steve Grubbc2f0c7c2005-05-06 12:38:39 +0100102
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103/* Records can be lost in several ways:
104 0) [suppressed in audit_alloc]
105 1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
106 2) out of memory in audit_log_move [alloc_skb]
107 3) suppressed due to audit_rate_limit
108 4) suppressed due to audit_backlog_limit
109*/
110static atomic_t audit_lost = ATOMIC_INIT(0);
111
112/* The netlink socket. */
113static struct sock *audit_sock;
114
Amy Griffisf368c07d2006-04-07 16:55:56 -0400115/* Inotify handle. */
116struct inotify_handle *audit_ih;
117
118/* Hash for inode-based rules */
119struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
120
David Woodhouseb7d11252005-05-19 10:56:58 +0100121/* The audit_freelist is a list of pre-allocated audit buffers (if more
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
123 * being placed on the freelist). */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124static DEFINE_SPINLOCK(audit_freelist_lock);
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700125static int audit_freelist_count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126static LIST_HEAD(audit_freelist);
127
David Woodhouseb7d11252005-05-19 10:56:58 +0100128static struct sk_buff_head audit_skb_queue;
129static struct task_struct *kauditd_task;
130static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
David Woodhouse9ad9ad32005-06-22 15:04:33 +0100131static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132
Amy Griffisf368c07d2006-04-07 16:55:56 -0400133/* Serialize requests from userspace. */
134static DEFINE_MUTEX(audit_cmd_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
136/* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
137 * audit records. Since printk uses a 1024 byte buffer, this buffer
138 * should be at least that large. */
139#define AUDIT_BUFSIZ 1024
140
141/* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the
142 * audit_freelist. Doing so eliminates many kmalloc/kfree calls. */
143#define AUDIT_MAXFREE (2*NR_CPUS)
144
145/* The audit_buffer is used when formatting an audit record. The caller
146 * locks briefly to get the record off the freelist or to allocate the
147 * buffer, and locks briefly to send the buffer to the netlink layer or
148 * to place it on a transmit queue. Multiple audit_buffers can be in
149 * use simultaneously. */
150struct audit_buffer {
151 struct list_head list;
Chris Wright8fc61152005-05-06 15:54:17 +0100152 struct sk_buff *skb; /* formatted skb ready to send */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 struct audit_context *ctx; /* NULL or associated context */
Al Viro9796fdd2005-10-21 03:22:03 -0400154 gfp_t gfp_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155};
156
Steve Grubbc0404992005-05-13 18:17:42 +0100157static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
158{
Eric Paris50397bd2008-01-07 18:14:19 -0500159 if (ab) {
160 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
161 nlh->nlmsg_pid = pid;
162 }
Steve Grubbc0404992005-05-13 18:17:42 +0100163}
164
Dustin Kirkland8c8570f2005-11-03 17:15:16 +0000165void audit_panic(const char *message)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166{
167 switch (audit_failure)
168 {
169 case AUDIT_FAIL_SILENT:
170 break;
171 case AUDIT_FAIL_PRINTK:
Eric Paris320f1b12008-01-23 22:55:05 -0500172 if (printk_ratelimit())
173 printk(KERN_ERR "audit: %s\n", message);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 break;
175 case AUDIT_FAIL_PANIC:
Eric Parisb29ee872008-02-21 15:53:05 -0500176 /* test audit_pid since printk is always losey, why bother? */
177 if (audit_pid)
178 panic("audit: %s\n", message);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 break;
180 }
181}
182
183static inline int audit_rate_check(void)
184{
185 static unsigned long last_check = 0;
186 static int messages = 0;
187 static DEFINE_SPINLOCK(lock);
188 unsigned long flags;
189 unsigned long now;
190 unsigned long elapsed;
191 int retval = 0;
192
193 if (!audit_rate_limit) return 1;
194
195 spin_lock_irqsave(&lock, flags);
196 if (++messages < audit_rate_limit) {
197 retval = 1;
198 } else {
199 now = jiffies;
200 elapsed = now - last_check;
201 if (elapsed > HZ) {
202 last_check = now;
203 messages = 0;
204 retval = 1;
205 }
206 }
207 spin_unlock_irqrestore(&lock, flags);
208
209 return retval;
210}
211
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700212/**
213 * audit_log_lost - conditionally log lost audit message event
214 * @message: the message stating reason for lost audit message
215 *
216 * Emit at least 1 message per second, even if audit_rate_check is
217 * throttling.
218 * Always increment the lost messages counter.
219*/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220void audit_log_lost(const char *message)
221{
222 static unsigned long last_msg = 0;
223 static DEFINE_SPINLOCK(lock);
224 unsigned long flags;
225 unsigned long now;
226 int print;
227
228 atomic_inc(&audit_lost);
229
230 print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit);
231
232 if (!print) {
233 spin_lock_irqsave(&lock, flags);
234 now = jiffies;
235 if (now - last_msg > HZ) {
236 print = 1;
237 last_msg = now;
238 }
239 spin_unlock_irqrestore(&lock, flags);
240 }
241
242 if (print) {
Eric Paris320f1b12008-01-23 22:55:05 -0500243 if (printk_ratelimit())
244 printk(KERN_WARNING
245 "audit: audit_lost=%d audit_rate_limit=%d "
246 "audit_backlog_limit=%d\n",
247 atomic_read(&audit_lost),
248 audit_rate_limit,
249 audit_backlog_limit);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 audit_panic(message);
251 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252}
253
Eric Paris1a6b9f22008-01-07 17:09:31 -0500254static int audit_log_config_change(char *function_name, int new, int old,
255 uid_t loginuid, u32 sid, int allow_changes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256{
Eric Paris1a6b9f22008-01-07 17:09:31 -0500257 struct audit_buffer *ab;
258 int rc = 0;
Steve Grubb6a01b072007-01-19 14:39:55 -0500259
Eric Paris1a6b9f22008-01-07 17:09:31 -0500260 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
261 audit_log_format(ab, "%s=%d old=%d by auid=%u", function_name, new,
262 old, loginuid);
Steve Grubbce29b682006-04-01 18:29:34 -0500263 if (sid) {
264 char *ctx = NULL;
265 u32 len;
Eric Paris1a6b9f22008-01-07 17:09:31 -0500266
Ahmed S. Darwish2a862b32008-03-01 21:54:38 +0200267 rc = security_secid_to_secctx(sid, &ctx, &len);
Eric Paris1a6b9f22008-01-07 17:09:31 -0500268 if (rc) {
269 audit_log_format(ab, " sid=%u", sid);
270 allow_changes = 0; /* Something weird, deny request */
271 } else {
272 audit_log_format(ab, " subj=%s", ctx);
Ahmed S. Darwish2a862b32008-03-01 21:54:38 +0200273 security_release_secctx(ctx, len);
Eric Paris1a6b9f22008-01-07 17:09:31 -0500274 }
Steve Grubb6a01b072007-01-19 14:39:55 -0500275 }
Eric Paris1a6b9f22008-01-07 17:09:31 -0500276 audit_log_format(ab, " res=%d", allow_changes);
277 audit_log_end(ab);
278 return rc;
279}
280
281static int audit_do_config_change(char *function_name, int *to_change,
282 int new, uid_t loginuid, u32 sid)
283{
284 int allow_changes, rc = 0, old = *to_change;
285
286 /* check if we are locked */
287 if (audit_enabled == AUDIT_LOCKED)
288 allow_changes = 0;
289 else
290 allow_changes = 1;
291
292 if (audit_enabled != AUDIT_OFF) {
293 rc = audit_log_config_change(function_name, new, old,
294 loginuid, sid, allow_changes);
295 if (rc)
296 allow_changes = 0;
297 }
Steve Grubb6a01b072007-01-19 14:39:55 -0500298
299 /* If we are allowed, make the change */
Eric Paris1a6b9f22008-01-07 17:09:31 -0500300 if (allow_changes == 1)
301 *to_change = new;
Steve Grubb6a01b072007-01-19 14:39:55 -0500302 /* Not allowed, update reason */
303 else if (rc == 0)
304 rc = -EPERM;
305 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306}
307
Eric Paris1a6b9f22008-01-07 17:09:31 -0500308static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sid)
309{
310 return audit_do_config_change("audit_rate_limit", &audit_rate_limit,
311 limit, loginuid, sid);
312}
313
Steve Grubbce29b682006-04-01 18:29:34 -0500314static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315{
Eric Paris1a6b9f22008-01-07 17:09:31 -0500316 return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit,
317 limit, loginuid, sid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318}
319
Steve Grubbce29b682006-04-01 18:29:34 -0500320static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321{
Eric Parisb593d382008-01-08 17:38:31 -0500322 int rc;
Eric Paris1a6b9f22008-01-07 17:09:31 -0500323 if (state < AUDIT_OFF || state > AUDIT_LOCKED)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 return -EINVAL;
Steve Grubbce29b682006-04-01 18:29:34 -0500325
Eric Parisb593d382008-01-08 17:38:31 -0500326 rc = audit_do_config_change("audit_enabled", &audit_enabled, state,
327 loginuid, sid);
328
329 if (!rc)
330 audit_ever_enabled |= !!state;
331
332 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333}
334
Steve Grubbce29b682006-04-01 18:29:34 -0500335static int audit_set_failure(int state, uid_t loginuid, u32 sid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 if (state != AUDIT_FAIL_SILENT
338 && state != AUDIT_FAIL_PRINTK
339 && state != AUDIT_FAIL_PANIC)
340 return -EINVAL;
Steve Grubbce29b682006-04-01 18:29:34 -0500341
Eric Paris1a6b9f22008-01-07 17:09:31 -0500342 return audit_do_config_change("audit_failure", &audit_failure, state,
343 loginuid, sid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344}
345
Adrian Bunk97a41e22006-01-08 01:02:17 -0800346static int kauditd_thread(void *dummy)
David Woodhouseb7d11252005-05-19 10:56:58 +0100347{
348 struct sk_buff *skb;
349
Rafael J. Wysocki83144182007-07-17 04:03:35 -0700350 set_freezable();
Andrew Morton4899b8b2006-10-06 00:43:48 -0700351 while (!kthread_should_stop()) {
David Woodhouseb7d11252005-05-19 10:56:58 +0100352 skb = skb_dequeue(&audit_skb_queue);
David Woodhouse9ad9ad32005-06-22 15:04:33 +0100353 wake_up(&audit_backlog_wait);
David Woodhouseb7d11252005-05-19 10:56:58 +0100354 if (skb) {
355 if (audit_pid) {
Pavel Emelyanov75c03712008-03-20 15:39:41 -0700356 int err = netlink_unicast(audit_sock, skb, audit_nlk_pid, 0);
David Woodhouseb7d11252005-05-19 10:56:58 +0100357 if (err < 0) {
358 BUG_ON(err != -ECONNREFUSED); /* Shoudn't happen */
359 printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
Eric Parisb29ee872008-02-21 15:53:05 -0500360 audit_log_lost("auditd dissapeared\n");
David Woodhouseb7d11252005-05-19 10:56:58 +0100361 audit_pid = 0;
362 }
363 } else {
Eric Paris320f1b12008-01-23 22:55:05 -0500364 if (printk_ratelimit())
365 printk(KERN_NOTICE "%s\n", skb->data +
366 NLMSG_SPACE(0));
367 else
368 audit_log_lost("printk limit exceeded\n");
David Woodhouseb7d11252005-05-19 10:56:58 +0100369 kfree_skb(skb);
370 }
371 } else {
372 DECLARE_WAITQUEUE(wait, current);
373 set_current_state(TASK_INTERRUPTIBLE);
374 add_wait_queue(&kauditd_wait, &wait);
375
Pierre Ossman7a4ae742005-12-12 00:37:22 -0800376 if (!skb_queue_len(&audit_skb_queue)) {
377 try_to_freeze();
David Woodhouseb7d11252005-05-19 10:56:58 +0100378 schedule();
Pierre Ossman7a4ae742005-12-12 00:37:22 -0800379 }
David Woodhouseb7d11252005-05-19 10:56:58 +0100380
381 __set_current_state(TASK_RUNNING);
382 remove_wait_queue(&kauditd_wait, &wait);
383 }
384 }
Andrew Morton4899b8b2006-10-06 00:43:48 -0700385 return 0;
David Woodhouseb7d11252005-05-19 10:56:58 +0100386}
387
Miloslav Trmac522ed772007-07-15 23:40:56 -0700388static int audit_prepare_user_tty(pid_t pid, uid_t loginuid)
389{
390 struct task_struct *tsk;
391 int err;
392
393 read_lock(&tasklist_lock);
394 tsk = find_task_by_pid(pid);
395 err = -ESRCH;
396 if (!tsk)
397 goto out;
398 err = 0;
399
400 spin_lock_irq(&tsk->sighand->siglock);
401 if (!tsk->signal->audit_tty)
402 err = -EPERM;
403 spin_unlock_irq(&tsk->sighand->siglock);
404 if (err)
405 goto out;
406
407 tty_audit_push_task(tsk, loginuid);
408out:
409 read_unlock(&tasklist_lock);
410 return err;
411}
412
Al Viro9044e6b2006-05-22 01:09:24 -0400413int audit_send_list(void *_dest)
414{
415 struct audit_netlink_list *dest = _dest;
416 int pid = dest->pid;
417 struct sk_buff *skb;
418
419 /* wait for parent to finish and send an ACK */
Amy Griffisf368c07d2006-04-07 16:55:56 -0400420 mutex_lock(&audit_cmd_mutex);
421 mutex_unlock(&audit_cmd_mutex);
Al Viro9044e6b2006-05-22 01:09:24 -0400422
423 while ((skb = __skb_dequeue(&dest->q)) != NULL)
424 netlink_unicast(audit_sock, skb, pid, 0);
425
426 kfree(dest);
427
428 return 0;
429}
430
Al Viro74c3cbe2007-07-22 08:04:18 -0400431#ifdef CONFIG_AUDIT_TREE
432static int prune_tree_thread(void *unused)
433{
434 mutex_lock(&audit_cmd_mutex);
435 audit_prune_trees();
436 mutex_unlock(&audit_cmd_mutex);
437 return 0;
438}
439
440void audit_schedule_prune(void)
441{
442 kthread_run(prune_tree_thread, NULL, "audit_prune_tree");
443}
444#endif
445
Al Viro9044e6b2006-05-22 01:09:24 -0400446struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
447 int multi, void *payload, int size)
448{
449 struct sk_buff *skb;
450 struct nlmsghdr *nlh;
451 int len = NLMSG_SPACE(size);
452 void *data;
453 int flags = multi ? NLM_F_MULTI : 0;
454 int t = done ? NLMSG_DONE : type;
455
456 skb = alloc_skb(len, GFP_KERNEL);
457 if (!skb)
458 return NULL;
459
460 nlh = NLMSG_PUT(skb, pid, seq, t, size);
461 nlh->nlmsg_flags = flags;
462 data = NLMSG_DATA(nlh);
463 memcpy(data, payload, size);
464 return skb;
465
466nlmsg_failure: /* Used by NLMSG_PUT */
467 if (skb)
468 kfree_skb(skb);
469 return NULL;
470}
471
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700472/**
473 * audit_send_reply - send an audit reply message via netlink
474 * @pid: process id to send reply to
475 * @seq: sequence number
476 * @type: audit message type
477 * @done: done (last) flag
478 * @multi: multi-part message flag
479 * @payload: payload data
480 * @size: payload size
481 *
482 * Allocates an skb, builds the netlink message, and sends it to the pid.
483 * No failure notifications.
484 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485void audit_send_reply(int pid, int seq, int type, int done, int multi,
486 void *payload, int size)
487{
488 struct sk_buff *skb;
Al Viro9044e6b2006-05-22 01:09:24 -0400489 skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 if (!skb)
David Woodhouseb7d11252005-05-19 10:56:58 +0100491 return;
David Woodhouseb7d11252005-05-19 10:56:58 +0100492 /* Ignore failure. It'll only happen if the sender goes away,
493 because our timeout is set to infinite. */
494 netlink_unicast(audit_sock, skb, pid, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496}
497
498/*
499 * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
500 * control messages.
501 */
Darrel Goeddelc7bdb542006-06-27 13:26:11 -0700502static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503{
504 int err = 0;
505
506 switch (msg_type) {
507 case AUDIT_GET:
508 case AUDIT_LIST:
Amy Griffis93315ed2006-02-07 12:05:27 -0500509 case AUDIT_LIST_RULES:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 case AUDIT_SET:
511 case AUDIT_ADD:
Amy Griffis93315ed2006-02-07 12:05:27 -0500512 case AUDIT_ADD_RULE:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 case AUDIT_DEL:
Amy Griffis93315ed2006-02-07 12:05:27 -0500514 case AUDIT_DEL_RULE:
Steve Grubbc2f0c7c2005-05-06 12:38:39 +0100515 case AUDIT_SIGNAL_INFO:
Miloslav Trmac522ed772007-07-15 23:40:56 -0700516 case AUDIT_TTY_GET:
517 case AUDIT_TTY_SET:
Al Viro74c3cbe2007-07-22 08:04:18 -0400518 case AUDIT_TRIM:
519 case AUDIT_MAKE_EQUIV:
Darrel Goeddelc7bdb542006-06-27 13:26:11 -0700520 if (security_netlink_recv(skb, CAP_AUDIT_CONTROL))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521 err = -EPERM;
522 break;
Steve Grubb05474102005-05-21 00:18:37 +0100523 case AUDIT_USER:
Robert P. J. Day039b6b32007-05-08 00:29:20 -0700524 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
525 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
Darrel Goeddelc7bdb542006-06-27 13:26:11 -0700526 if (security_netlink_recv(skb, CAP_AUDIT_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 err = -EPERM;
528 break;
529 default: /* bad msg */
530 err = -EINVAL;
531 }
532
533 return err;
534}
535
Eric Paris50397bd2008-01-07 18:14:19 -0500536static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
537 u32 pid, u32 uid, uid_t auid, u32 sid)
538{
539 int rc = 0;
540 char *ctx = NULL;
541 u32 len;
542
543 if (!audit_enabled) {
544 *ab = NULL;
545 return rc;
546 }
547
548 *ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
549 audit_log_format(*ab, "user pid=%d uid=%u auid=%u",
550 pid, uid, auid);
551 if (sid) {
Ahmed S. Darwish2a862b32008-03-01 21:54:38 +0200552 rc = security_secid_to_secctx(sid, &ctx, &len);
Eric Paris50397bd2008-01-07 18:14:19 -0500553 if (rc)
554 audit_log_format(*ab, " ssid=%u", sid);
Ahmed S. Darwish2a862b32008-03-01 21:54:38 +0200555 else {
Eric Paris50397bd2008-01-07 18:14:19 -0500556 audit_log_format(*ab, " subj=%s", ctx);
Ahmed S. Darwish2a862b32008-03-01 21:54:38 +0200557 security_release_secctx(ctx, len);
558 }
Eric Paris50397bd2008-01-07 18:14:19 -0500559 }
560
561 return rc;
562}
563
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
565{
Steve Grubbe7c34972006-04-03 09:08:13 -0400566 u32 uid, pid, seq, sid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 void *data;
568 struct audit_status *status_get, status_set;
569 int err;
Steve Grubbc0404992005-05-13 18:17:42 +0100570 struct audit_buffer *ab;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571 u16 msg_type = nlh->nlmsg_type;
Serge Hallync94c2572005-04-29 16:27:17 +0100572 uid_t loginuid; /* loginuid of sender */
Al Viroe1396062006-05-25 10:19:47 -0400573 struct audit_sig_info *sig_data;
Eric Paris50397bd2008-01-07 18:14:19 -0500574 char *ctx = NULL;
Al Viroe1396062006-05-25 10:19:47 -0400575 u32 len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576
Darrel Goeddelc7bdb542006-06-27 13:26:11 -0700577 err = audit_netlink_ok(skb, msg_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 if (err)
579 return err;
580
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700581 /* As soon as there's any sign of userspace auditd,
582 * start kauditd to talk to it */
David Woodhouseb7d11252005-05-19 10:56:58 +0100583 if (!kauditd_task)
584 kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
585 if (IS_ERR(kauditd_task)) {
586 err = PTR_ERR(kauditd_task);
587 kauditd_task = NULL;
588 return err;
589 }
590
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 pid = NETLINK_CREDS(skb)->pid;
592 uid = NETLINK_CREDS(skb)->uid;
Serge Hallync94c2572005-04-29 16:27:17 +0100593 loginuid = NETLINK_CB(skb).loginuid;
Steve Grubbe7c34972006-04-03 09:08:13 -0400594 sid = NETLINK_CB(skb).sid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595 seq = nlh->nlmsg_seq;
596 data = NLMSG_DATA(nlh);
597
598 switch (msg_type) {
599 case AUDIT_GET:
600 status_set.enabled = audit_enabled;
601 status_set.failure = audit_failure;
602 status_set.pid = audit_pid;
603 status_set.rate_limit = audit_rate_limit;
604 status_set.backlog_limit = audit_backlog_limit;
605 status_set.lost = atomic_read(&audit_lost);
David Woodhouseb7d11252005-05-19 10:56:58 +0100606 status_set.backlog = skb_queue_len(&audit_skb_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_GET, 0, 0,
608 &status_set, sizeof(status_set));
609 break;
610 case AUDIT_SET:
611 if (nlh->nlmsg_len < sizeof(struct audit_status))
612 return -EINVAL;
613 status_get = (struct audit_status *)data;
614 if (status_get->mask & AUDIT_STATUS_ENABLED) {
Steve Grubbce29b682006-04-01 18:29:34 -0500615 err = audit_set_enabled(status_get->enabled,
616 loginuid, sid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 if (err < 0) return err;
618 }
619 if (status_get->mask & AUDIT_STATUS_FAILURE) {
Steve Grubbce29b682006-04-01 18:29:34 -0500620 err = audit_set_failure(status_get->failure,
621 loginuid, sid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 if (err < 0) return err;
623 }
624 if (status_get->mask & AUDIT_STATUS_PID) {
Eric Paris1a6b9f22008-01-07 17:09:31 -0500625 int new_pid = status_get->pid;
626
627 if (audit_enabled != AUDIT_OFF)
628 audit_log_config_change("audit_pid", new_pid,
629 audit_pid, loginuid,
630 sid, 1);
631
632 audit_pid = new_pid;
Pavel Emelyanov75c03712008-03-20 15:39:41 -0700633 audit_nlk_pid = NETLINK_CB(skb).pid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 }
635 if (status_get->mask & AUDIT_STATUS_RATE_LIMIT)
Serge E. Hallyn5d136a02006-04-27 16:45:14 -0500636 err = audit_set_rate_limit(status_get->rate_limit,
Steve Grubbce29b682006-04-01 18:29:34 -0500637 loginuid, sid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638 if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
Serge E. Hallyn5d136a02006-04-27 16:45:14 -0500639 err = audit_set_backlog_limit(status_get->backlog_limit,
Steve Grubbce29b682006-04-01 18:29:34 -0500640 loginuid, sid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 break;
Steve Grubb05474102005-05-21 00:18:37 +0100642 case AUDIT_USER:
Robert P. J. Day039b6b32007-05-08 00:29:20 -0700643 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
644 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
David Woodhouse4a4cd632005-06-22 14:56:47 +0100645 if (!audit_enabled && msg_type != AUDIT_USER_AVC)
646 return 0;
David Woodhouse0f45aa12005-06-19 19:35:50 +0100647
David Woodhouse5bb289b2005-06-24 14:14:05 +0100648 err = audit_filter_user(&NETLINK_CB(skb), msg_type);
David Woodhouse4a4cd632005-06-22 14:56:47 +0100649 if (err == 1) {
650 err = 0;
Miloslav Trmac522ed772007-07-15 23:40:56 -0700651 if (msg_type == AUDIT_USER_TTY) {
652 err = audit_prepare_user_tty(pid, loginuid);
653 if (err)
654 break;
655 }
Eric Paris50397bd2008-01-07 18:14:19 -0500656 audit_log_common_recv_msg(&ab, msg_type, pid, uid,
657 loginuid, sid);
Miloslav Trmac522ed772007-07-15 23:40:56 -0700658
Eric Paris50397bd2008-01-07 18:14:19 -0500659 if (msg_type != AUDIT_USER_TTY)
660 audit_log_format(ab, " msg='%.1024s'",
661 (char *)data);
662 else {
663 int size;
664
665 audit_log_format(ab, " msg=");
666 size = nlmsg_len(nlh);
667 audit_log_n_untrustedstring(ab, size,
668 data);
David Woodhouse4a4cd632005-06-22 14:56:47 +0100669 }
Eric Paris50397bd2008-01-07 18:14:19 -0500670 audit_set_pid(ab, pid);
671 audit_log_end(ab);
David Woodhouse0f45aa12005-06-19 19:35:50 +0100672 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673 break;
674 case AUDIT_ADD:
675 case AUDIT_DEL:
Amy Griffis93315ed2006-02-07 12:05:27 -0500676 if (nlmsg_len(nlh) < sizeof(struct audit_rule))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 return -EINVAL;
Eric Paris1a6b9f22008-01-07 17:09:31 -0500678 if (audit_enabled == AUDIT_LOCKED) {
Eric Paris50397bd2008-01-07 18:14:19 -0500679 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
680 uid, loginuid, sid);
681
682 audit_log_format(ab, " audit_enabled=%d res=0",
683 audit_enabled);
684 audit_log_end(ab);
Steve Grubb6a01b072007-01-19 14:39:55 -0500685 return -EPERM;
686 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 /* fallthrough */
688 case AUDIT_LIST:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689 err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
Amy Griffis93315ed2006-02-07 12:05:27 -0500690 uid, seq, data, nlmsg_len(nlh),
Steve Grubbce29b682006-04-01 18:29:34 -0500691 loginuid, sid);
Amy Griffis93315ed2006-02-07 12:05:27 -0500692 break;
693 case AUDIT_ADD_RULE:
694 case AUDIT_DEL_RULE:
695 if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
696 return -EINVAL;
Eric Paris1a6b9f22008-01-07 17:09:31 -0500697 if (audit_enabled == AUDIT_LOCKED) {
Eric Paris50397bd2008-01-07 18:14:19 -0500698 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
699 uid, loginuid, sid);
700
701 audit_log_format(ab, " audit_enabled=%d res=0",
702 audit_enabled);
703 audit_log_end(ab);
Steve Grubb6a01b072007-01-19 14:39:55 -0500704 return -EPERM;
705 }
Amy Griffis93315ed2006-02-07 12:05:27 -0500706 /* fallthrough */
707 case AUDIT_LIST_RULES:
708 err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
709 uid, seq, data, nlmsg_len(nlh),
Steve Grubbce29b682006-04-01 18:29:34 -0500710 loginuid, sid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 break;
Al Viro74c3cbe2007-07-22 08:04:18 -0400712 case AUDIT_TRIM:
713 audit_trim_trees();
Eric Paris50397bd2008-01-07 18:14:19 -0500714
715 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
716 uid, loginuid, sid);
717
Al Viro74c3cbe2007-07-22 08:04:18 -0400718 audit_log_format(ab, " op=trim res=1");
719 audit_log_end(ab);
720 break;
721 case AUDIT_MAKE_EQUIV: {
722 void *bufp = data;
723 u32 sizes[2];
724 size_t len = nlmsg_len(nlh);
725 char *old, *new;
726
727 err = -EINVAL;
728 if (len < 2 * sizeof(u32))
729 break;
730 memcpy(sizes, bufp, 2 * sizeof(u32));
731 bufp += 2 * sizeof(u32);
732 len -= 2 * sizeof(u32);
733 old = audit_unpack_string(&bufp, &len, sizes[0]);
734 if (IS_ERR(old)) {
735 err = PTR_ERR(old);
736 break;
737 }
738 new = audit_unpack_string(&bufp, &len, sizes[1]);
739 if (IS_ERR(new)) {
740 err = PTR_ERR(new);
741 kfree(old);
742 break;
743 }
744 /* OK, here comes... */
745 err = audit_tag_tree(old, new);
746
Eric Paris50397bd2008-01-07 18:14:19 -0500747 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
748 uid, loginuid, sid);
749
Al Viro74c3cbe2007-07-22 08:04:18 -0400750 audit_log_format(ab, " op=make_equiv old=");
751 audit_log_untrustedstring(ab, old);
752 audit_log_format(ab, " new=");
753 audit_log_untrustedstring(ab, new);
754 audit_log_format(ab, " res=%d", !err);
755 audit_log_end(ab);
756 kfree(old);
757 kfree(new);
758 break;
759 }
Steve Grubbc2f0c7c2005-05-06 12:38:39 +0100760 case AUDIT_SIGNAL_INFO:
Ahmed S. Darwish2a862b32008-03-01 21:54:38 +0200761 err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
Al Viroe1396062006-05-25 10:19:47 -0400762 if (err)
763 return err;
764 sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
765 if (!sig_data) {
Ahmed S. Darwish2a862b32008-03-01 21:54:38 +0200766 security_release_secctx(ctx, len);
Al Viroe1396062006-05-25 10:19:47 -0400767 return -ENOMEM;
768 }
769 sig_data->uid = audit_sig_uid;
770 sig_data->pid = audit_sig_pid;
771 memcpy(sig_data->ctx, ctx, len);
Ahmed S. Darwish2a862b32008-03-01 21:54:38 +0200772 security_release_secctx(ctx, len);
Daniel Walker5600b892007-10-18 03:06:10 -0700773 audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
Al Viroe1396062006-05-25 10:19:47 -0400774 0, 0, sig_data, sizeof(*sig_data) + len);
775 kfree(sig_data);
Steve Grubbc2f0c7c2005-05-06 12:38:39 +0100776 break;
Miloslav Trmac522ed772007-07-15 23:40:56 -0700777 case AUDIT_TTY_GET: {
778 struct audit_tty_status s;
779 struct task_struct *tsk;
780
781 read_lock(&tasklist_lock);
782 tsk = find_task_by_pid(pid);
783 if (!tsk)
784 err = -ESRCH;
785 else {
786 spin_lock_irq(&tsk->sighand->siglock);
787 s.enabled = tsk->signal->audit_tty != 0;
788 spin_unlock_irq(&tsk->sighand->siglock);
789 }
790 read_unlock(&tasklist_lock);
791 audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_TTY_GET, 0, 0,
792 &s, sizeof(s));
793 break;
794 }
795 case AUDIT_TTY_SET: {
796 struct audit_tty_status *s;
797 struct task_struct *tsk;
798
799 if (nlh->nlmsg_len < sizeof(struct audit_tty_status))
800 return -EINVAL;
801 s = data;
802 if (s->enabled != 0 && s->enabled != 1)
803 return -EINVAL;
804 read_lock(&tasklist_lock);
805 tsk = find_task_by_pid(pid);
806 if (!tsk)
807 err = -ESRCH;
808 else {
809 spin_lock_irq(&tsk->sighand->siglock);
810 tsk->signal->audit_tty = s->enabled != 0;
811 spin_unlock_irq(&tsk->sighand->siglock);
812 }
813 read_unlock(&tasklist_lock);
814 break;
815 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 default:
817 err = -EINVAL;
818 break;
819 }
820
821 return err < 0 ? err : 0;
822}
823
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700824/*
825 * Get message from skb (based on rtnetlink_rcv_skb). Each message is
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826 * processed by audit_receive_msg. Malformed skbs with wrong length are
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700827 * discarded silently.
828 */
Herbert Xu2a0a6eb2005-05-03 14:55:09 -0700829static void audit_receive_skb(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830{
831 int err;
832 struct nlmsghdr *nlh;
833 u32 rlen;
834
835 while (skb->len >= NLMSG_SPACE(0)) {
Arnaldo Carvalho de Melob529ccf2007-04-25 19:08:35 -0700836 nlh = nlmsg_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837 if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
Herbert Xu2a0a6eb2005-05-03 14:55:09 -0700838 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
840 if (rlen > skb->len)
841 rlen = skb->len;
842 if ((err = audit_receive_msg(skb, nlh))) {
843 netlink_ack(skb, nlh, err);
844 } else if (nlh->nlmsg_flags & NLM_F_ACK)
845 netlink_ack(skb, nlh, 0);
846 skb_pull(skb, rlen);
847 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848}
849
850/* Receive messages from netlink socket. */
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -0700851static void audit_receive(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852{
Amy Griffisf368c07d2006-04-07 16:55:56 -0400853 mutex_lock(&audit_cmd_mutex);
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -0700854 audit_receive_skb(skb);
Amy Griffisf368c07d2006-04-07 16:55:56 -0400855 mutex_unlock(&audit_cmd_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856}
857
Amy Griffisf368c07d2006-04-07 16:55:56 -0400858#ifdef CONFIG_AUDITSYSCALL
859static const struct inotify_operations audit_inotify_ops = {
860 .handle_event = audit_handle_ievent,
861 .destroy_watch = audit_free_parent,
862};
863#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864
865/* Initialize audit support at boot time. */
866static int __init audit_init(void)
867{
Amy Griffisf368c07d2006-04-07 16:55:56 -0400868 int i;
Amy Griffisf368c07d2006-04-07 16:55:56 -0400869
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 printk(KERN_INFO "audit: initializing netlink socket (%s)\n",
871 audit_default ? "enabled" : "disabled");
Eric W. Biedermanb4b51022007-09-12 13:05:38 +0200872 audit_sock = netlink_kernel_create(&init_net, NETLINK_AUDIT, 0,
873 audit_receive, NULL, THIS_MODULE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 if (!audit_sock)
875 audit_panic("cannot initialize netlink socket");
Amy Griffis71e1c782006-03-06 22:40:05 -0500876 else
877 audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700878
David Woodhouseb7d11252005-05-19 10:56:58 +0100879 skb_queue_head_init(&audit_skb_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 audit_initialized = 1;
881 audit_enabled = audit_default;
Eric Parisb593d382008-01-08 17:38:31 -0500882 audit_ever_enabled |= !!audit_default;
Darrel Goeddel3dc7e312006-03-10 18:14:06 -0600883
David Woodhouse9ad9ad32005-06-22 15:04:33 +0100884 audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
Amy Griffisf368c07d2006-04-07 16:55:56 -0400885
886#ifdef CONFIG_AUDITSYSCALL
887 audit_ih = inotify_init(&audit_inotify_ops);
888 if (IS_ERR(audit_ih))
889 audit_panic("cannot initialize inotify handle");
Amy Griffis69884342006-07-13 13:17:12 -0400890#endif
Amy Griffisf368c07d2006-04-07 16:55:56 -0400891
892 for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
893 INIT_LIST_HEAD(&audit_inode_hash[i]);
Amy Griffisf368c07d2006-04-07 16:55:56 -0400894
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 return 0;
896}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700897__initcall(audit_init);
898
899/* Process kernel command-line parameter at boot time. audit=0 or audit=1. */
900static int __init audit_enable(char *str)
901{
902 audit_default = !!simple_strtol(str, NULL, 0);
903 printk(KERN_INFO "audit: %s%s\n",
904 audit_default ? "enabled" : "disabled",
905 audit_initialized ? "" : " (after initialization)");
Eric Parisb593d382008-01-08 17:38:31 -0500906 if (audit_initialized) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907 audit_enabled = audit_default;
Eric Parisb593d382008-01-08 17:38:31 -0500908 audit_ever_enabled |= !!audit_default;
909 }
OGAWA Hirofumi9b410462006-03-31 02:30:33 -0800910 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911}
912
913__setup("audit=", audit_enable);
914
Chris Wright16e19042005-05-06 15:53:34 +0100915static void audit_buffer_free(struct audit_buffer *ab)
916{
917 unsigned long flags;
918
Chris Wright8fc61152005-05-06 15:54:17 +0100919 if (!ab)
920 return;
921
Chris Wright5ac52f32005-05-06 15:54:53 +0100922 if (ab->skb)
923 kfree_skb(ab->skb);
David Woodhouseb7d11252005-05-19 10:56:58 +0100924
Chris Wright16e19042005-05-06 15:53:34 +0100925 spin_lock_irqsave(&audit_freelist_lock, flags);
Serge E. Hallyn5d136a02006-04-27 16:45:14 -0500926 if (audit_freelist_count > AUDIT_MAXFREE)
Chris Wright16e19042005-05-06 15:53:34 +0100927 kfree(ab);
Serge E. Hallyn5d136a02006-04-27 16:45:14 -0500928 else {
929 audit_freelist_count++;
Chris Wright16e19042005-05-06 15:53:34 +0100930 list_add(&ab->list, &audit_freelist);
Serge E. Hallyn5d136a02006-04-27 16:45:14 -0500931 }
Chris Wright16e19042005-05-06 15:53:34 +0100932 spin_unlock_irqrestore(&audit_freelist_lock, flags);
933}
934
Steve Grubbc0404992005-05-13 18:17:42 +0100935static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
Al Virodd0fc662005-10-07 07:46:04 +0100936 gfp_t gfp_mask, int type)
Chris Wright16e19042005-05-06 15:53:34 +0100937{
938 unsigned long flags;
939 struct audit_buffer *ab = NULL;
Steve Grubbc0404992005-05-13 18:17:42 +0100940 struct nlmsghdr *nlh;
Chris Wright16e19042005-05-06 15:53:34 +0100941
942 spin_lock_irqsave(&audit_freelist_lock, flags);
943 if (!list_empty(&audit_freelist)) {
944 ab = list_entry(audit_freelist.next,
945 struct audit_buffer, list);
946 list_del(&ab->list);
947 --audit_freelist_count;
948 }
949 spin_unlock_irqrestore(&audit_freelist_lock, flags);
950
951 if (!ab) {
David Woodhouse4332bdd2005-05-06 15:59:57 +0100952 ab = kmalloc(sizeof(*ab), gfp_mask);
Chris Wright16e19042005-05-06 15:53:34 +0100953 if (!ab)
Chris Wright8fc61152005-05-06 15:54:17 +0100954 goto err;
Chris Wright16e19042005-05-06 15:53:34 +0100955 }
Chris Wright8fc61152005-05-06 15:54:17 +0100956
David Woodhouse4332bdd2005-05-06 15:59:57 +0100957 ab->skb = alloc_skb(AUDIT_BUFSIZ, gfp_mask);
Chris Wright5ac52f32005-05-06 15:54:53 +0100958 if (!ab->skb)
Chris Wright8fc61152005-05-06 15:54:17 +0100959 goto err;
960
David Woodhouseb7d11252005-05-19 10:56:58 +0100961 ab->ctx = ctx;
David Woodhouse9ad9ad32005-06-22 15:04:33 +0100962 ab->gfp_mask = gfp_mask;
Steve Grubbc0404992005-05-13 18:17:42 +0100963 nlh = (struct nlmsghdr *)skb_put(ab->skb, NLMSG_SPACE(0));
964 nlh->nlmsg_type = type;
965 nlh->nlmsg_flags = 0;
966 nlh->nlmsg_pid = 0;
967 nlh->nlmsg_seq = 0;
Chris Wright16e19042005-05-06 15:53:34 +0100968 return ab;
Chris Wright8fc61152005-05-06 15:54:17 +0100969err:
970 audit_buffer_free(ab);
971 return NULL;
Chris Wright16e19042005-05-06 15:53:34 +0100972}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700973
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700974/**
975 * audit_serial - compute a serial number for the audit record
976 *
977 * Compute a serial number for the audit record. Audit records are
David Woodhousebfb44962005-05-21 21:08:09 +0100978 * written to user-space as soon as they are generated, so a complete
979 * audit record may be written in several pieces. The timestamp of the
980 * record and this serial number are used by the user-space tools to
981 * determine which pieces belong to the same audit record. The
982 * (timestamp,serial) tuple is unique for each syscall and is live from
983 * syscall entry to syscall exit.
984 *
David Woodhousebfb44962005-05-21 21:08:09 +0100985 * NOTE: Another possibility is to store the formatted records off the
986 * audit context (for those records that have a context), and emit them
987 * all at syscall exit. However, this could delay the reporting of
988 * significant errors until syscall exit (or never, if the system
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700989 * halts).
990 */
David Woodhousebfb44962005-05-21 21:08:09 +0100991unsigned int audit_serial(void)
992{
Ingo Molnar34af9462006-06-27 02:53:55 -0700993 static DEFINE_SPINLOCK(serial_lock);
David Woodhoused5b454f2005-07-15 12:56:03 +0100994 static unsigned int serial = 0;
David Woodhousebfb44962005-05-21 21:08:09 +0100995
David Woodhoused5b454f2005-07-15 12:56:03 +0100996 unsigned long flags;
997 unsigned int ret;
David Woodhousebfb44962005-05-21 21:08:09 +0100998
David Woodhoused5b454f2005-07-15 12:56:03 +0100999 spin_lock_irqsave(&serial_lock, flags);
David Woodhousebfb44962005-05-21 21:08:09 +01001000 do {
David Woodhousece625a82005-07-18 14:24:46 -04001001 ret = ++serial;
1002 } while (unlikely(!ret));
David Woodhoused5b454f2005-07-15 12:56:03 +01001003 spin_unlock_irqrestore(&serial_lock, flags);
David Woodhousebfb44962005-05-21 21:08:09 +01001004
David Woodhoused5b454f2005-07-15 12:56:03 +01001005 return ret;
David Woodhousebfb44962005-05-21 21:08:09 +01001006}
1007
Daniel Walker5600b892007-10-18 03:06:10 -07001008static inline void audit_get_stamp(struct audit_context *ctx,
David Woodhousebfb44962005-05-21 21:08:09 +01001009 struct timespec *t, unsigned int *serial)
1010{
1011 if (ctx)
1012 auditsc_get_stamp(ctx, t, serial);
1013 else {
1014 *t = CURRENT_TIME;
1015 *serial = audit_serial();
1016 }
1017}
1018
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019/* Obtain an audit buffer. This routine does locking to obtain the
1020 * audit buffer, but then no locking is required for calls to
1021 * audit_log_*format. If the tsk is a task that is currently in a
1022 * syscall, then the syscall is marked as auditable and an audit record
1023 * will be written at syscall exit. If there is no associated task, tsk
1024 * should be NULL. */
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001025
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001026/**
1027 * audit_log_start - obtain an audit buffer
1028 * @ctx: audit_context (may be NULL)
1029 * @gfp_mask: type of allocation
1030 * @type: audit message type
1031 *
1032 * Returns audit_buffer pointer on success or NULL on error.
1033 *
1034 * Obtain an audit buffer. This routine does locking to obtain the
1035 * audit buffer, but then no locking is required for calls to
1036 * audit_log_*format. If the task (ctx) is a task that is currently in a
1037 * syscall, then the syscall is marked as auditable and an audit record
1038 * will be written at syscall exit. If there is no associated task, then
1039 * task context (ctx) should be NULL.
1040 */
Al Viro9796fdd2005-10-21 03:22:03 -04001041struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001042 int type)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043{
1044 struct audit_buffer *ab = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001045 struct timespec t;
Andrew Mortonef00be02008-01-10 11:02:39 -08001046 unsigned int uninitialized_var(serial);
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001047 int reserve;
David Woodhouseac4cec42005-07-02 14:08:48 +01001048 unsigned long timeout_start = jiffies;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049
1050 if (!audit_initialized)
1051 return NULL;
1052
Dustin Kirklandc8edc802005-11-03 16:12:36 +00001053 if (unlikely(audit_filter_type(type)))
1054 return NULL;
1055
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001056 if (gfp_mask & __GFP_WAIT)
1057 reserve = 0;
1058 else
Daniel Walker5600b892007-10-18 03:06:10 -07001059 reserve = 5; /* Allow atomic callers to go up to five
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001060 entries over the normal backlog limit */
1061
1062 while (audit_backlog_limit
1063 && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
David Woodhouseac4cec42005-07-02 14:08:48 +01001064 if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time
1065 && time_before(jiffies, timeout_start + audit_backlog_wait_time)) {
1066
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001067 /* Wait for auditd to drain the queue a little */
1068 DECLARE_WAITQUEUE(wait, current);
1069 set_current_state(TASK_INTERRUPTIBLE);
1070 add_wait_queue(&audit_backlog_wait, &wait);
1071
1072 if (audit_backlog_limit &&
1073 skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
David Woodhouseac4cec42005-07-02 14:08:48 +01001074 schedule_timeout(timeout_start + audit_backlog_wait_time - jiffies);
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001075
1076 __set_current_state(TASK_RUNNING);
1077 remove_wait_queue(&audit_backlog_wait, &wait);
David Woodhouseac4cec42005-07-02 14:08:48 +01001078 continue;
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001079 }
Eric Paris320f1b12008-01-23 22:55:05 -05001080 if (audit_rate_check() && printk_ratelimit())
David Woodhousefb19b4c2005-05-19 14:55:56 +01001081 printk(KERN_WARNING
1082 "audit: audit_backlog=%d > "
1083 "audit_backlog_limit=%d\n",
1084 skb_queue_len(&audit_skb_queue),
1085 audit_backlog_limit);
1086 audit_log_lost("backlog limit exceeded");
David Woodhouseac4cec42005-07-02 14:08:48 +01001087 audit_backlog_wait_time = audit_backlog_wait_overflow;
1088 wake_up(&audit_backlog_wait);
David Woodhousefb19b4c2005-05-19 14:55:56 +01001089 return NULL;
1090 }
1091
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001092 ab = audit_buffer_alloc(ctx, gfp_mask, type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093 if (!ab) {
1094 audit_log_lost("out of memory in audit_log_start");
1095 return NULL;
1096 }
1097
David Woodhousebfb44962005-05-21 21:08:09 +01001098 audit_get_stamp(ab->ctx, &t, &serial);
Chris Wright197c69c2005-05-11 10:54:05 +01001099
Linus Torvalds1da177e2005-04-16 15:20:36 -07001100 audit_log_format(ab, "audit(%lu.%03lu:%u): ",
1101 t.tv_sec, t.tv_nsec/1000000, serial);
1102 return ab;
1103}
1104
Chris Wright8fc61152005-05-06 15:54:17 +01001105/**
Chris Wright5ac52f32005-05-06 15:54:53 +01001106 * audit_expand - expand skb in the audit buffer
Chris Wright8fc61152005-05-06 15:54:17 +01001107 * @ab: audit_buffer
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001108 * @extra: space to add at tail of the skb
Chris Wright8fc61152005-05-06 15:54:17 +01001109 *
1110 * Returns 0 (no space) on failed expansion, or available space if
1111 * successful.
1112 */
David Woodhousee3b926b2005-05-10 18:56:08 +01001113static inline int audit_expand(struct audit_buffer *ab, int extra)
Chris Wright8fc61152005-05-06 15:54:17 +01001114{
Chris Wright5ac52f32005-05-06 15:54:53 +01001115 struct sk_buff *skb = ab->skb;
Herbert Xu406a1d82008-01-28 20:47:09 -08001116 int oldtail = skb_tailroom(skb);
1117 int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask);
1118 int newtail = skb_tailroom(skb);
1119
Chris Wright5ac52f32005-05-06 15:54:53 +01001120 if (ret < 0) {
1121 audit_log_lost("out of memory in audit_expand");
Chris Wright8fc61152005-05-06 15:54:17 +01001122 return 0;
Chris Wright5ac52f32005-05-06 15:54:53 +01001123 }
Herbert Xu406a1d82008-01-28 20:47:09 -08001124
1125 skb->truesize += newtail - oldtail;
1126 return newtail;
Chris Wright8fc61152005-05-06 15:54:17 +01001127}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001129/*
1130 * Format an audit message into the audit buffer. If there isn't enough
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131 * room in the audit buffer, more room will be allocated and vsnprint
1132 * will be called a second time. Currently, we assume that a printk
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001133 * can't format message larger than 1024 bytes, so we don't either.
1134 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
1136 va_list args)
1137{
1138 int len, avail;
Chris Wright5ac52f32005-05-06 15:54:53 +01001139 struct sk_buff *skb;
David Woodhouseeecb0a72005-05-10 18:58:51 +01001140 va_list args2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141
1142 if (!ab)
1143 return;
1144
Chris Wright5ac52f32005-05-06 15:54:53 +01001145 BUG_ON(!ab->skb);
1146 skb = ab->skb;
1147 avail = skb_tailroom(skb);
1148 if (avail == 0) {
David Woodhousee3b926b2005-05-10 18:56:08 +01001149 avail = audit_expand(ab, AUDIT_BUFSIZ);
Chris Wright8fc61152005-05-06 15:54:17 +01001150 if (!avail)
1151 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 }
David Woodhouseeecb0a72005-05-10 18:58:51 +01001153 va_copy(args2, args);
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001154 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155 if (len >= avail) {
1156 /* The printk buffer is 1024 bytes long, so if we get
1157 * here and AUDIT_BUFSIZ is at least 1024, then we can
1158 * log everything that printk could have logged. */
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001159 avail = audit_expand(ab,
1160 max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
Chris Wright8fc61152005-05-06 15:54:17 +01001161 if (!avail)
1162 goto out;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001163 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001164 }
Richard Knutsson148b38d2008-01-10 11:02:40 -08001165 va_end(args2);
Steve Grubb168b7172005-05-19 10:24:22 +01001166 if (len > 0)
1167 skb_put(skb, len);
Chris Wright8fc61152005-05-06 15:54:17 +01001168out:
1169 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001170}
1171
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001172/**
1173 * audit_log_format - format a message into the audit buffer.
1174 * @ab: audit_buffer
1175 * @fmt: format string
1176 * @...: optional parameters matching @fmt string
1177 *
1178 * All the work is done in audit_log_vformat.
1179 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
1181{
1182 va_list args;
1183
1184 if (!ab)
1185 return;
1186 va_start(args, fmt);
1187 audit_log_vformat(ab, fmt, args);
1188 va_end(args);
1189}
1190
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001191/**
1192 * audit_log_hex - convert a buffer to hex and append it to the audit skb
1193 * @ab: the audit_buffer
1194 * @buf: buffer to convert to hex
1195 * @len: length of @buf to be converted
1196 *
1197 * No return value; failure to expand is silently ignored.
1198 *
1199 * This function will take the passed buf and convert it into a string of
1200 * ascii hex digits. The new string is placed onto the skb.
1201 */
1202void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf,
Steve Grubb168b7172005-05-19 10:24:22 +01001203 size_t len)
83c7d092005-04-29 15:54:44 +01001204{
Steve Grubb168b7172005-05-19 10:24:22 +01001205 int i, avail, new_len;
1206 unsigned char *ptr;
1207 struct sk_buff *skb;
1208 static const unsigned char *hex = "0123456789ABCDEF";
83c7d092005-04-29 15:54:44 +01001209
Amy Griffis8ef2d302006-09-07 17:03:02 -04001210 if (!ab)
1211 return;
1212
Steve Grubb168b7172005-05-19 10:24:22 +01001213 BUG_ON(!ab->skb);
1214 skb = ab->skb;
1215 avail = skb_tailroom(skb);
1216 new_len = len<<1;
1217 if (new_len >= avail) {
1218 /* Round the buffer request up to the next multiple */
1219 new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1);
1220 avail = audit_expand(ab, new_len);
1221 if (!avail)
1222 return;
1223 }
1224
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001225 ptr = skb_tail_pointer(skb);
Steve Grubb168b7172005-05-19 10:24:22 +01001226 for (i=0; i<len; i++) {
1227 *ptr++ = hex[(buf[i] & 0xF0)>>4]; /* Upper nibble */
1228 *ptr++ = hex[buf[i] & 0x0F]; /* Lower nibble */
1229 }
1230 *ptr = 0;
1231 skb_put(skb, len << 1); /* new string is twice the old string */
83c7d092005-04-29 15:54:44 +01001232}
1233
Amy Griffis9c937dc2006-06-08 23:19:31 -04001234/*
1235 * Format a string of no more than slen characters into the audit buffer,
1236 * enclosed in quote marks.
1237 */
1238static void audit_log_n_string(struct audit_buffer *ab, size_t slen,
1239 const char *string)
1240{
1241 int avail, new_len;
1242 unsigned char *ptr;
1243 struct sk_buff *skb;
1244
Amy Griffis8ef2d302006-09-07 17:03:02 -04001245 if (!ab)
1246 return;
1247
Amy Griffis9c937dc2006-06-08 23:19:31 -04001248 BUG_ON(!ab->skb);
1249 skb = ab->skb;
1250 avail = skb_tailroom(skb);
1251 new_len = slen + 3; /* enclosing quotes + null terminator */
1252 if (new_len > avail) {
1253 avail = audit_expand(ab, new_len);
1254 if (!avail)
1255 return;
1256 }
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001257 ptr = skb_tail_pointer(skb);
Amy Griffis9c937dc2006-06-08 23:19:31 -04001258 *ptr++ = '"';
1259 memcpy(ptr, string, slen);
1260 ptr += slen;
1261 *ptr++ = '"';
1262 *ptr = 0;
1263 skb_put(skb, slen + 2); /* don't include null terminator */
1264}
1265
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001266/**
Eric Parisde6bbd12008-01-07 14:31:58 -05001267 * audit_string_contains_control - does a string need to be logged in hex
Dave Jonesf706d5d2008-03-28 14:15:56 -07001268 * @string: string to be checked
1269 * @len: max length of the string to check
Eric Parisde6bbd12008-01-07 14:31:58 -05001270 */
1271int audit_string_contains_control(const char *string, size_t len)
1272{
1273 const unsigned char *p;
1274 for (p = string; p < (const unsigned char *)string + len && *p; p++) {
1275 if (*p == '"' || *p < 0x21 || *p > 0x7f)
1276 return 1;
1277 }
1278 return 0;
1279}
1280
1281/**
Miloslav Trmac522ed772007-07-15 23:40:56 -07001282 * audit_log_n_untrustedstring - log a string that may contain random characters
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001283 * @ab: audit_buffer
Dave Jonesf706d5d2008-03-28 14:15:56 -07001284 * @len: length of string (not including trailing null)
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001285 * @string: string to be logged
1286 *
1287 * This code will escape a string that is passed to it if the string
1288 * contains a control character, unprintable character, double quote mark,
Steve Grubb168b7172005-05-19 10:24:22 +01001289 * or a space. Unescaped strings will start and end with a double quote mark.
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001290 * Strings that are escaped are printed in hex (2 digits per char).
Amy Griffis9c937dc2006-06-08 23:19:31 -04001291 *
1292 * The caller specifies the number of characters in the string to log, which may
1293 * or may not be the entire string.
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001294 */
Eric Parisde6bbd12008-01-07 14:31:58 -05001295void audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len,
1296 const char *string)
83c7d092005-04-29 15:54:44 +01001297{
Eric Parisde6bbd12008-01-07 14:31:58 -05001298 if (audit_string_contains_control(string, len))
1299 audit_log_hex(ab, string, len);
1300 else
1301 audit_log_n_string(ab, len, string);
83c7d092005-04-29 15:54:44 +01001302}
1303
Amy Griffis9c937dc2006-06-08 23:19:31 -04001304/**
Miloslav Trmac522ed772007-07-15 23:40:56 -07001305 * audit_log_untrustedstring - log a string that may contain random characters
Amy Griffis9c937dc2006-06-08 23:19:31 -04001306 * @ab: audit_buffer
1307 * @string: string to be logged
1308 *
Miloslav Trmac522ed772007-07-15 23:40:56 -07001309 * Same as audit_log_n_untrustedstring(), except that strlen is used to
Amy Griffis9c937dc2006-06-08 23:19:31 -04001310 * determine string length.
1311 */
Eric Parisde6bbd12008-01-07 14:31:58 -05001312void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
Amy Griffis9c937dc2006-06-08 23:19:31 -04001313{
Eric Parisde6bbd12008-01-07 14:31:58 -05001314 audit_log_n_untrustedstring(ab, strlen(string), string);
Amy Griffis9c937dc2006-06-08 23:19:31 -04001315}
1316
Steve Grubb168b7172005-05-19 10:24:22 +01001317/* This is a helper-function to print the escaped d_path */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
Jan Blunck44707fd2008-02-14 19:38:33 -08001319 struct path *path)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001320{
Jan Blunck44707fd2008-02-14 19:38:33 -08001321 char *p, *pathname;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322
Chris Wright8fc61152005-05-06 15:54:17 +01001323 if (prefix)
1324 audit_log_format(ab, " %s", prefix);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001325
Steve Grubb168b7172005-05-19 10:24:22 +01001326 /* We will allow 11 spaces for ' (deleted)' to be appended */
Jan Blunck44707fd2008-02-14 19:38:33 -08001327 pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
1328 if (!pathname) {
Steve Grubb168b7172005-05-19 10:24:22 +01001329 audit_log_format(ab, "<no memory>");
1330 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331 }
Jan Blunckcf28b482008-02-14 19:38:44 -08001332 p = d_path(path, pathname, PATH_MAX+11);
Steve Grubb168b7172005-05-19 10:24:22 +01001333 if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
1334 /* FIXME: can we save some information here? */
1335 audit_log_format(ab, "<too long>");
Daniel Walker5600b892007-10-18 03:06:10 -07001336 } else
Steve Grubb168b7172005-05-19 10:24:22 +01001337 audit_log_untrustedstring(ab, p);
Jan Blunck44707fd2008-02-14 19:38:33 -08001338 kfree(pathname);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001339}
1340
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001341/**
1342 * audit_log_end - end one audit record
1343 * @ab: the audit_buffer
1344 *
1345 * The netlink_* functions cannot be called inside an irq context, so
1346 * the audit buffer is placed on a queue and a tasklet is scheduled to
Linus Torvalds1da177e2005-04-16 15:20:36 -07001347 * remove them from the queue outside the irq context. May be called in
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001348 * any context.
1349 */
David Woodhouseb7d11252005-05-19 10:56:58 +01001350void audit_log_end(struct audit_buffer *ab)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001351{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001352 if (!ab)
1353 return;
1354 if (!audit_rate_check()) {
1355 audit_log_lost("rate limit exceeded");
1356 } else {
Steve Grubb8d07a672008-02-21 16:59:22 -05001357 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
David Woodhouseb7d11252005-05-19 10:56:58 +01001358 if (audit_pid) {
David Woodhouseb7d11252005-05-19 10:56:58 +01001359 nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
1360 skb_queue_tail(&audit_skb_queue, ab->skb);
1361 ab->skb = NULL;
1362 wake_up_interruptible(&kauditd_wait);
Steve Grubb8d07a672008-02-21 16:59:22 -05001363 } else if (nlh->nlmsg_type != AUDIT_EOE) {
1364 if (printk_ratelimit()) {
1365 printk(KERN_NOTICE "type=%d %s\n",
1366 nlh->nlmsg_type,
1367 ab->skb->data + NLMSG_SPACE(0));
1368 } else
1369 audit_log_lost("printk limit exceeded\n");
David Woodhouseb7d11252005-05-19 10:56:58 +01001370 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001371 }
Chris Wright16e19042005-05-06 15:53:34 +01001372 audit_buffer_free(ab);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373}
1374
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001375/**
1376 * audit_log - Log an audit record
1377 * @ctx: audit context
1378 * @gfp_mask: type of allocation
1379 * @type: audit message type
1380 * @fmt: format string to use
1381 * @...: variable parameters matching the format string
1382 *
1383 * This is a convenience function that calls audit_log_start,
1384 * audit_log_vformat, and audit_log_end. It may be called
1385 * in any context.
1386 */
Daniel Walker5600b892007-10-18 03:06:10 -07001387void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001388 const char *fmt, ...)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001389{
1390 struct audit_buffer *ab;
1391 va_list args;
1392
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001393 ab = audit_log_start(ctx, gfp_mask, type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394 if (ab) {
1395 va_start(args, fmt);
1396 audit_log_vformat(ab, fmt, args);
1397 va_end(args);
1398 audit_log_end(ab);
1399 }
1400}
lorenzo@gnu.orgbf45da92006-03-09 00:33:47 +01001401
1402EXPORT_SYMBOL(audit_log_start);
1403EXPORT_SYMBOL(audit_log_end);
1404EXPORT_SYMBOL(audit_log_format);
1405EXPORT_SYMBOL(audit_log);