1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44#include <linux/init.h>
45#include <asm/types.h>
46#include <asm/atomic.h>
47#include <linux/mm.h>
48#include <linux/module.h>
49#include <linux/err.h>
50#include <linux/kthread.h>
51
52#include <linux/audit.h>
53
54#include <net/sock.h>
55#include <net/netlink.h>
56#include <linux/skbuff.h>
57#include <linux/netlink.h>
58#include <linux/selinux.h>
59#include <linux/inotify.h>
60#include <linux/freezer.h>
61#include <linux/tty.h>
62
63#include "audit.h"
64
65
66
67static int audit_initialized;
68
69
70
71
72int audit_enabled;
73
74
75static int audit_default;
76
77
78static int audit_failure = AUDIT_FAIL_PRINTK;
79
80
81
82int audit_pid;
83
84
85
86
87static int audit_rate_limit;
88
89
90static int audit_backlog_limit = 64;
91static int audit_backlog_wait_time = 60 * HZ;
92static int audit_backlog_wait_overflow = 0;
93
94
95uid_t audit_sig_uid = -1;
96pid_t audit_sig_pid = -1;
97u32 audit_sig_sid = 0;
98
99
100
101
102
103
104
105
106static atomic_t audit_lost = ATOMIC_INIT(0);
107
108
109static struct sock *audit_sock;
110
111
112struct inotify_handle *audit_ih;
113
114
115struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
116
117
118
119
120static DEFINE_SPINLOCK(audit_freelist_lock);
121static int audit_freelist_count;
122static LIST_HEAD(audit_freelist);
123
124static struct sk_buff_head audit_skb_queue;
125static struct task_struct *kauditd_task;
126static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
127static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
128
129
130static DEFINE_MUTEX(audit_cmd_mutex);
131
132
133
134
135#define AUDIT_BUFSIZ 1024
136
137
138
139#define AUDIT_MAXFREE (2*NR_CPUS)
140
141
142
143
144
145
146struct audit_buffer {
147 struct list_head list;
148 struct sk_buff *skb;
149 struct audit_context *ctx;
150 gfp_t gfp_mask;
151};
152
153static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
154{
155 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
156 nlh->nlmsg_pid = pid;
157}
158
159void audit_panic(const char *message)
160{
161 switch (audit_failure)
162 {
163 case AUDIT_FAIL_SILENT:
164 break;
165 case AUDIT_FAIL_PRINTK:
166 printk(KERN_ERR "audit: %s\n", message);
167 break;
168 case AUDIT_FAIL_PANIC:
169 panic("audit: %s\n", message);
170 break;
171 }
172}
173
174static inline int audit_rate_check(void)
175{
176 static unsigned long last_check = 0;
177 static int messages = 0;
178 static DEFINE_SPINLOCK(lock);
179 unsigned long flags;
180 unsigned long now;
181 unsigned long elapsed;
182 int retval = 0;
183
184 if (!audit_rate_limit) return 1;
185
186 spin_lock_irqsave(&lock, flags);
187 if (++messages < audit_rate_limit) {
188 retval = 1;
189 } else {
190 now = jiffies;
191 elapsed = now - last_check;
192 if (elapsed > HZ) {
193 last_check = now;
194 messages = 0;
195 retval = 1;
196 }
197 }
198 spin_unlock_irqrestore(&lock, flags);
199
200 return retval;
201}
202
203
204
205
206
207
208
209
210
211void audit_log_lost(const char *message)
212{
213 static unsigned long last_msg = 0;
214 static DEFINE_SPINLOCK(lock);
215 unsigned long flags;
216 unsigned long now;
217 int print;
218
219 atomic_inc(&audit_lost);
220
221 print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit);
222
223 if (!print) {
224 spin_lock_irqsave(&lock, flags);
225 now = jiffies;
226 if (now - last_msg > HZ) {
227 print = 1;
228 last_msg = now;
229 }
230 spin_unlock_irqrestore(&lock, flags);
231 }
232
233 if (print) {
234 printk(KERN_WARNING
235 "audit: audit_lost=%d audit_rate_limit=%d audit_backlog_limit=%d\n",
236 atomic_read(&audit_lost),
237 audit_rate_limit,
238 audit_backlog_limit);
239 audit_panic(message);
240 }
241}
242
243static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sid)
244{
245 int res, rc = 0, old = audit_rate_limit;
246
247
248 if (audit_enabled == 2)
249 res = 0;
250 else
251 res = 1;
252
253 if (sid) {
254 char *ctx = NULL;
255 u32 len;
256 if ((rc = selinux_sid_to_string(sid, &ctx, &len)) == 0) {
257 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
258 "audit_rate_limit=%d old=%d by auid=%u"
259 " subj=%s res=%d",
260 limit, old, loginuid, ctx, res);
261 kfree(ctx);
262 } else
263 res = 0;
264 }
265 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
266 "audit_rate_limit=%d old=%d by auid=%u res=%d",
267 limit, old, loginuid, res);
268
269
270 if (res == 1)
271 audit_rate_limit = limit;
272
273 else if (rc == 0)
274 rc = -EPERM;
275 return rc;
276}
277
278static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid)
279{
280 int res, rc = 0, old = audit_backlog_limit;
281
282
283 if (audit_enabled == 2)
284 res = 0;
285 else
286 res = 1;
287
288 if (sid) {
289 char *ctx = NULL;
290 u32 len;
291 if ((rc = selinux_sid_to_string(sid, &ctx, &len)) == 0) {
292 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
293 "audit_backlog_limit=%d old=%d by auid=%u"
294 " subj=%s res=%d",
295 limit, old, loginuid, ctx, res);
296 kfree(ctx);
297 } else
298 res = 0;
299 }
300 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
301 "audit_backlog_limit=%d old=%d by auid=%u res=%d",
302 limit, old, loginuid, res);
303
304
305 if (res == 1)
306 audit_backlog_limit = limit;
307
308 else if (rc == 0)
309 rc = -EPERM;
310 return rc;
311}
312
313static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
314{
315 int res, rc = 0, old = audit_enabled;
316
317 if (state < 0 || state > 2)
318 return -EINVAL;
319
320
321 if (audit_enabled == 2)
322 res = 0;
323 else
324 res = 1;
325
326 if (sid) {
327 char *ctx = NULL;
328 u32 len;
329 if ((rc = selinux_sid_to_string(sid, &ctx, &len)) == 0) {
330 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
331 "audit_enabled=%d old=%d by auid=%u"
332 " subj=%s res=%d",
333 state, old, loginuid, ctx, res);
334 kfree(ctx);
335 } else
336 res = 0;
337 }
338 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
339 "audit_enabled=%d old=%d by auid=%u res=%d",
340 state, old, loginuid, res);
341
342
343 if (res == 1)
344 audit_enabled = state;
345
346 else if (rc == 0)
347 rc = -EPERM;
348 return rc;
349}
350
351static int audit_set_failure(int state, uid_t loginuid, u32 sid)
352{
353 int res, rc = 0, old = audit_failure;
354
355 if (state != AUDIT_FAIL_SILENT
356 && state != AUDIT_FAIL_PRINTK
357 && state != AUDIT_FAIL_PANIC)
358 return -EINVAL;
359
360
361 if (audit_enabled == 2)
362 res = 0;
363 else
364 res = 1;
365
366 if (sid) {
367 char *ctx = NULL;
368 u32 len;
369 if ((rc = selinux_sid_to_string(sid, &ctx, &len)) == 0) {
370 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
371 "audit_failure=%d old=%d by auid=%u"
372 " subj=%s res=%d",
373 state, old, loginuid, ctx, res);
374 kfree(ctx);
375 } else
376 res = 0;
377 }
378 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
379 "audit_failure=%d old=%d by auid=%u res=%d",
380 state, old, loginuid, res);
381
382
383 if (res == 1)
384 audit_failure = state;
385
386 else if (rc == 0)
387 rc = -EPERM;
388 return rc;
389}
390
391static int kauditd_thread(void *dummy)
392{
393 struct sk_buff *skb;
394
395 set_freezable();
396 while (!kthread_should_stop()) {
397 skb = skb_dequeue(&audit_skb_queue);
398 wake_up(&audit_backlog_wait);
399 if (skb) {
400 if (audit_pid) {
401 int err = netlink_unicast(audit_sock, skb, audit_pid, 0);
402 if (err < 0) {
403 BUG_ON(err != -ECONNREFUSED);
404 printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
405 audit_pid = 0;
406 }
407 } else {
408 printk(KERN_NOTICE "%s\n", skb->data + NLMSG_SPACE(0));
409 kfree_skb(skb);
410 }
411 } else {
412 DECLARE_WAITQUEUE(wait, current);
413 set_current_state(TASK_INTERRUPTIBLE);
414 add_wait_queue(&kauditd_wait, &wait);
415
416 if (!skb_queue_len(&audit_skb_queue)) {
417 try_to_freeze();
418 schedule();
419 }
420
421 __set_current_state(TASK_RUNNING);
422 remove_wait_queue(&kauditd_wait, &wait);
423 }
424 }
425 return 0;
426}
427
428static int audit_prepare_user_tty(pid_t pid, uid_t loginuid)
429{
430 struct task_struct *tsk;
431 int err;
432
433 read_lock(&tasklist_lock);
434 tsk = find_task_by_pid(pid);
435 err = -ESRCH;
436 if (!tsk)
437 goto out;
438 err = 0;
439
440 spin_lock_irq(&tsk->sighand->siglock);
441 if (!tsk->signal->audit_tty)
442 err = -EPERM;
443 spin_unlock_irq(&tsk->sighand->siglock);
444 if (err)
445 goto out;
446
447 tty_audit_push_task(tsk, loginuid);
448out:
449 read_unlock(&tasklist_lock);
450 return err;
451}
452
453int audit_send_list(void *_dest)
454{
455 struct audit_netlink_list *dest = _dest;
456 int pid = dest->pid;
457 struct sk_buff *skb;
458
459
460 mutex_lock(&audit_cmd_mutex);
461 mutex_unlock(&audit_cmd_mutex);
462
463 while ((skb = __skb_dequeue(&dest->q)) != NULL)
464 netlink_unicast(audit_sock, skb, pid, 0);
465
466 kfree(dest);
467
468 return 0;
469}
470
471#ifdef CONFIG_AUDIT_TREE
472static int prune_tree_thread(void *unused)
473{
474 mutex_lock(&audit_cmd_mutex);
475 audit_prune_trees();
476 mutex_unlock(&audit_cmd_mutex);
477 return 0;
478}
479
480void audit_schedule_prune(void)
481{
482 kthread_run(prune_tree_thread, NULL, "audit_prune_tree");
483}
484#endif
485
486struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
487 int multi, void *payload, int size)
488{
489 struct sk_buff *skb;
490 struct nlmsghdr *nlh;
491 int len = NLMSG_SPACE(size);
492 void *data;
493 int flags = multi ? NLM_F_MULTI : 0;
494 int t = done ? NLMSG_DONE : type;
495
496 skb = alloc_skb(len, GFP_KERNEL);
497 if (!skb)
498 return NULL;
499
500 nlh = NLMSG_PUT(skb, pid, seq, t, size);
501 nlh->nlmsg_flags = flags;
502 data = NLMSG_DATA(nlh);
503 memcpy(data, payload, size);
504 return skb;
505
506nlmsg_failure:
507 if (skb)
508 kfree_skb(skb);
509 return NULL;
510}
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525void audit_send_reply(int pid, int seq, int type, int done, int multi,
526 void *payload, int size)
527{
528 struct sk_buff *skb;
529 skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
530 if (!skb)
531 return;
532
533
534 netlink_unicast(audit_sock, skb, pid, 0);
535 return;
536}
537
538
539
540
541
542static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
543{
544 int err = 0;
545
546 switch (msg_type) {
547 case AUDIT_GET:
548 case AUDIT_LIST:
549 case AUDIT_LIST_RULES:
550 case AUDIT_SET:
551 case AUDIT_ADD:
552 case AUDIT_ADD_RULE:
553 case AUDIT_DEL:
554 case AUDIT_DEL_RULE:
555 case AUDIT_SIGNAL_INFO:
556 case AUDIT_TTY_GET:
557 case AUDIT_TTY_SET:
558 case AUDIT_TRIM:
559 case AUDIT_MAKE_EQUIV:
560 if (security_netlink_recv(skb, CAP_AUDIT_CONTROL))
561 err = -EPERM;
562 break;
563 case AUDIT_USER:
564 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
565 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
566 if (security_netlink_recv(skb, CAP_AUDIT_WRITE))
567 err = -EPERM;
568 break;
569 default:
570 err = -EINVAL;
571 }
572
573 return err;
574}
575
576static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
577{
578 u32 uid, pid, seq, sid;
579 void *data;
580 struct audit_status *status_get, status_set;
581 int err;
582 struct audit_buffer *ab;
583 u16 msg_type = nlh->nlmsg_type;
584 uid_t loginuid;
585 struct audit_sig_info *sig_data;
586 char *ctx;
587 u32 len;
588
589 err = audit_netlink_ok(skb, msg_type);
590 if (err)
591 return err;
592
593
594
595 if (!kauditd_task)
596 kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
597 if (IS_ERR(kauditd_task)) {
598 err = PTR_ERR(kauditd_task);
599 kauditd_task = NULL;
600 return err;
601 }
602
603 pid = NETLINK_CREDS(skb)->pid;
604 uid = NETLINK_CREDS(skb)->uid;
605 loginuid = NETLINK_CB(skb).loginuid;
606 sid = NETLINK_CB(skb).sid;
607 seq = nlh->nlmsg_seq;
608 data = NLMSG_DATA(nlh);
609
610 switch (msg_type) {
611 case AUDIT_GET:
612 status_set.enabled = audit_enabled;
613 status_set.failure = audit_failure;
614 status_set.pid = audit_pid;
615 status_set.rate_limit = audit_rate_limit;
616 status_set.backlog_limit = audit_backlog_limit;
617 status_set.lost = atomic_read(&audit_lost);
618 status_set.backlog = skb_queue_len(&audit_skb_queue);
619 audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_GET, 0, 0,
620 &status_set, sizeof(status_set));
621 break;
622 case AUDIT_SET:
623 if (nlh->nlmsg_len < sizeof(struct audit_status))
624 return -EINVAL;
625 status_get = (struct audit_status *)data;
626 if (status_get->mask & AUDIT_STATUS_ENABLED) {
627 err = audit_set_enabled(status_get->enabled,
628 loginuid, sid);
629 if (err < 0) return err;
630 }
631 if (status_get->mask & AUDIT_STATUS_FAILURE) {
632 err = audit_set_failure(status_get->failure,
633 loginuid, sid);
634 if (err < 0) return err;
635 }
636 if (status_get->mask & AUDIT_STATUS_PID) {
637 int old = audit_pid;
638 if (sid) {
639 if ((err = selinux_sid_to_string(
640 sid, &ctx, &len)))
641 return err;
642 else
643 audit_log(NULL, GFP_KERNEL,
644 AUDIT_CONFIG_CHANGE,
645 "audit_pid=%d old=%d by auid=%u subj=%s",
646 status_get->pid, old,
647 loginuid, ctx);
648 kfree(ctx);
649 } else
650 audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
651 "audit_pid=%d old=%d by auid=%u",
652 status_get->pid, old, loginuid);
653 audit_pid = status_get->pid;
654 }
655 if (status_get->mask & AUDIT_STATUS_RATE_LIMIT)
656 err = audit_set_rate_limit(status_get->rate_limit,
657 loginuid, sid);
658 if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
659 err = audit_set_backlog_limit(status_get->backlog_limit,
660 loginuid, sid);
661 break;
662 case AUDIT_USER:
663 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
664 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
665 if (!audit_enabled && msg_type != AUDIT_USER_AVC)
666 return 0;
667
668 err = audit_filter_user(&NETLINK_CB(skb), msg_type);
669 if (err == 1) {
670 err = 0;
671 if (msg_type == AUDIT_USER_TTY) {
672 err = audit_prepare_user_tty(pid, loginuid);
673 if (err)
674 break;
675 }
676 ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
677 if (ab) {
678 audit_log_format(ab,
679 "user pid=%d uid=%u auid=%u",
680 pid, uid, loginuid);
681 if (sid) {
682 if (selinux_sid_to_string(
683 sid, &ctx, &len)) {
684 audit_log_format(ab,
685 " ssid=%u", sid);
686
687 } else
688 audit_log_format(ab,
689 " subj=%s", ctx);
690 kfree(ctx);
691 }
692 if (msg_type != AUDIT_USER_TTY)
693 audit_log_format(ab, " msg='%.1024s'",
694 (char *)data);
695 else {
696 int size;
697
698 audit_log_format(ab, " msg=");
699 size = nlmsg_len(nlh);
700 audit_log_n_untrustedstring(ab, size,
701 data);
702 }
703 audit_set_pid(ab, pid);
704 audit_log_end(ab);
705 }
706 }
707 break;
708 case AUDIT_ADD:
709 case AUDIT_DEL:
710 if (nlmsg_len(nlh) < sizeof(struct audit_rule))
711 return -EINVAL;
712 if (audit_enabled == 2) {
713 ab = audit_log_start(NULL, GFP_KERNEL,
714 AUDIT_CONFIG_CHANGE);
715 if (ab) {
716 audit_log_format(ab,
717 "pid=%d uid=%u auid=%u",
718 pid, uid, loginuid);
719 if (sid) {
720 if (selinux_sid_to_string(
721 sid, &ctx, &len)) {
722 audit_log_format(ab,
723 " ssid=%u", sid);
724
725 } else
726 audit_log_format(ab,
727 " subj=%s", ctx);
728 kfree(ctx);
729 }
730 audit_log_format(ab, " audit_enabled=%d res=0",
731 audit_enabled);
732 audit_log_end(ab);
733 }
734 return -EPERM;
735 }
736
737 case AUDIT_LIST:
738 err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
739 uid, seq, data, nlmsg_len(nlh),
740 loginuid, sid);
741 break;
742 case AUDIT_ADD_RULE:
743 case AUDIT_DEL_RULE:
744 if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
745 return -EINVAL;
746 if (audit_enabled == 2) {
747 ab = audit_log_start(NULL, GFP_KERNEL,
748 AUDIT_CONFIG_CHANGE);
749 if (ab) {
750 audit_log_format(ab,
751 "pid=%d uid=%u auid=%u",
752 pid, uid, loginuid);
753 if (sid) {
754 if (selinux_sid_to_string(
755 sid, &ctx, &len)) {
756 audit_log_format(ab,
757 " ssid=%u", sid);
758
759 } else
760 audit_log_format(ab,
761 " subj=%s", ctx);
762 kfree(ctx);
763 }
764 audit_log_format(ab, " audit_enabled=%d res=0",
765 audit_enabled);
766 audit_log_end(ab);
767 }
768 return -EPERM;
769 }
770
771 case AUDIT_LIST_RULES:
772 err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
773 uid, seq, data, nlmsg_len(nlh),
774 loginuid, sid);
775 break;
776 case AUDIT_TRIM:
777 audit_trim_trees();
778 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
779 if (!ab)
780 break;
781 audit_log_format(ab, "auid=%u", loginuid);
782 if (sid) {
783 u32 len;
784 ctx = NULL;
785 if (selinux_sid_to_string(sid, &ctx, &len))
786 audit_log_format(ab, " ssid=%u", sid);
787 else
788 audit_log_format(ab, " subj=%s", ctx);
789 kfree(ctx);
790 }
791 audit_log_format(ab, " op=trim res=1");
792 audit_log_end(ab);
793 break;
794 case AUDIT_MAKE_EQUIV: {
795 void *bufp = data;
796 u32 sizes[2];
797 size_t len = nlmsg_len(nlh);
798 char *old, *new;
799
800 err = -EINVAL;
801 if (len < 2 * sizeof(u32))
802 break;
803 memcpy(sizes, bufp, 2 * sizeof(u32));
804 bufp += 2 * sizeof(u32);
805 len -= 2 * sizeof(u32);
806 old = audit_unpack_string(&bufp, &len, sizes[0]);
807 if (IS_ERR(old)) {
808 err = PTR_ERR(old);
809 break;
810 }
811 new = audit_unpack_string(&bufp, &len, sizes[1]);
812 if (IS_ERR(new)) {
813 err = PTR_ERR(new);
814 kfree(old);
815 break;
816 }
817
818 err = audit_tag_tree(old, new);
819
820 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
821 if (!ab) {
822 kfree(old);
823 kfree(new);
824 break;
825 }
826 audit_log_format(ab, "auid=%u", loginuid);
827 if (sid) {
828 u32 len;
829 ctx = NULL;
830 if (selinux_sid_to_string(sid, &ctx, &len))
831 audit_log_format(ab, " ssid=%u", sid);
832 else
833 audit_log_format(ab, " subj=%s", ctx);
834 kfree(ctx);
835 }
836 audit_log_format(ab, " op=make_equiv old=");
837 audit_log_untrustedstring(ab, old);
838 audit_log_format(ab, " new=");
839 audit_log_untrustedstring(ab, new);
840 audit_log_format(ab, " res=%d", !err);
841 audit_log_end(ab);
842 kfree(old);
843 kfree(new);
844 break;
845 }
846 case AUDIT_SIGNAL_INFO:
847 err = selinux_sid_to_string(audit_sig_sid, &ctx, &len);
848 if (err)
849 return err;
850 sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
851 if (!sig_data) {
852 kfree(ctx);
853 return -ENOMEM;
854 }
855 sig_data->uid = audit_sig_uid;
856 sig_data->pid = audit_sig_pid;
857 memcpy(sig_data->ctx, ctx, len);
858 kfree(ctx);
859 audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
860 0, 0, sig_data, sizeof(*sig_data) + len);
861 kfree(sig_data);
862 break;
863 case AUDIT_TTY_GET: {
864 struct audit_tty_status s;
865 struct task_struct *tsk;
866
867 read_lock(&tasklist_lock);
868 tsk = find_task_by_pid(pid);
869 if (!tsk)
870 err = -ESRCH;
871 else {
872 spin_lock_irq(&tsk->sighand->siglock);
873 s.enabled = tsk->signal->audit_tty != 0;
874 spin_unlock_irq(&tsk->sighand->siglock);
875 }
876 read_unlock(&tasklist_lock);
877 audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_TTY_GET, 0, 0,
878 &s, sizeof(s));
879 break;
880 }
881 case AUDIT_TTY_SET: {
882 struct audit_tty_status *s;
883 struct task_struct *tsk;
884
885 if (nlh->nlmsg_len < sizeof(struct audit_tty_status))
886 return -EINVAL;
887 s = data;
888 if (s->enabled != 0 && s->enabled != 1)
889 return -EINVAL;
890 read_lock(&tasklist_lock);
891 tsk = find_task_by_pid(pid);
892 if (!tsk)
893 err = -ESRCH;
894 else {
895 spin_lock_irq(&tsk->sighand->siglock);
896 tsk->signal->audit_tty = s->enabled != 0;
897 spin_unlock_irq(&tsk->sighand->siglock);
898 }
899 read_unlock(&tasklist_lock);
900 break;
901 }
902 default:
903 err = -EINVAL;
904 break;
905 }
906
907 return err < 0 ? err : 0;
908}
909
910
911
912
913
914
915static void audit_receive_skb(struct sk_buff *skb)
916{
917 int err;
918 struct nlmsghdr *nlh;
919 u32 rlen;
920
921 while (skb->len >= NLMSG_SPACE(0)) {
922 nlh = nlmsg_hdr(skb);
923 if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
924 return;
925 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
926 if (rlen > skb->len)
927 rlen = skb->len;
928 if ((err = audit_receive_msg(skb, nlh))) {
929 netlink_ack(skb, nlh, err);
930 } else if (nlh->nlmsg_flags & NLM_F_ACK)
931 netlink_ack(skb, nlh, 0);
932 skb_pull(skb, rlen);
933 }
934}
935
936
937static void audit_receive(struct sk_buff *skb)
938{
939 mutex_lock(&audit_cmd_mutex);
940 audit_receive_skb(skb);
941 mutex_unlock(&audit_cmd_mutex);
942}
943
944#ifdef CONFIG_AUDITSYSCALL
945static const struct inotify_operations audit_inotify_ops = {
946 .handle_event = audit_handle_ievent,
947 .destroy_watch = audit_free_parent,
948};
949#endif
950
951
952static int __init audit_init(void)
953{
954 int i;
955
956 printk(KERN_INFO "audit: initializing netlink socket (%s)\n",
957 audit_default ? "enabled" : "disabled");
958 audit_sock = netlink_kernel_create(&init_net, NETLINK_AUDIT, 0,
959 audit_receive, NULL, THIS_MODULE);
960 if (!audit_sock)
961 audit_panic("cannot initialize netlink socket");
962 else
963 audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
964
965 skb_queue_head_init(&audit_skb_queue);
966 audit_initialized = 1;
967 audit_enabled = audit_default;
968
969
970
971 selinux_audit_set_callback(&selinux_audit_rule_update);
972
973 audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
974
975#ifdef CONFIG_AUDITSYSCALL
976 audit_ih = inotify_init(&audit_inotify_ops);
977 if (IS_ERR(audit_ih))
978 audit_panic("cannot initialize inotify handle");
979#endif
980
981 for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
982 INIT_LIST_HEAD(&audit_inode_hash[i]);
983
984 return 0;
985}
986__initcall(audit_init);
987
988
989static int __init audit_enable(char *str)
990{
991 audit_default = !!simple_strtol(str, NULL, 0);
992 printk(KERN_INFO "audit: %s%s\n",
993 audit_default ? "enabled" : "disabled",
994 audit_initialized ? "" : " (after initialization)");
995 if (audit_initialized)
996 audit_enabled = audit_default;
997 return 1;
998}
999
1000__setup("audit=", audit_enable);
1001
1002static void audit_buffer_free(struct audit_buffer *ab)
1003{
1004 unsigned long flags;
1005
1006 if (!ab)
1007 return;
1008
1009 if (ab->skb)
1010 kfree_skb(ab->skb);
1011
1012 spin_lock_irqsave(&audit_freelist_lock, flags);
1013 if (audit_freelist_count > AUDIT_MAXFREE)
1014 kfree(ab);
1015 else {
1016 audit_freelist_count++;
1017 list_add(&ab->list, &audit_freelist);
1018 }
1019 spin_unlock_irqrestore(&audit_freelist_lock, flags);
1020}
1021
1022static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
1023 gfp_t gfp_mask, int type)
1024{
1025 unsigned long flags;
1026 struct audit_buffer *ab = NULL;
1027 struct nlmsghdr *nlh;
1028
1029 spin_lock_irqsave(&audit_freelist_lock, flags);
1030 if (!list_empty(&audit_freelist)) {
1031 ab = list_entry(audit_freelist.next,
1032 struct audit_buffer, list);
1033 list_del(&ab->list);
1034 --audit_freelist_count;
1035 }
1036 spin_unlock_irqrestore(&audit_freelist_lock, flags);
1037
1038 if (!ab) {
1039 ab = kmalloc(sizeof(*ab), gfp_mask);
1040 if (!ab)
1041 goto err;
1042 }
1043
1044 ab->skb = alloc_skb(AUDIT_BUFSIZ, gfp_mask);
1045 if (!ab->skb)
1046 goto err;
1047
1048 ab->ctx = ctx;
1049 ab->gfp_mask = gfp_mask;
1050 nlh = (struct nlmsghdr *)skb_put(ab->skb, NLMSG_SPACE(0));
1051 nlh->nlmsg_type = type;
1052 nlh->nlmsg_flags = 0;
1053 nlh->nlmsg_pid = 0;
1054 nlh->nlmsg_seq = 0;
1055 return ab;
1056err:
1057 audit_buffer_free(ab);
1058 return NULL;
1059}
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078unsigned int audit_serial(void)
1079{
1080 static DEFINE_SPINLOCK(serial_lock);
1081 static unsigned int serial = 0;
1082
1083 unsigned long flags;
1084 unsigned int ret;
1085
1086 spin_lock_irqsave(&serial_lock, flags);
1087 do {
1088 ret = ++serial;
1089 } while (unlikely(!ret));
1090 spin_unlock_irqrestore(&serial_lock, flags);
1091
1092 return ret;
1093}
1094
1095static inline void audit_get_stamp(struct audit_context *ctx,
1096 struct timespec *t, unsigned int *serial)
1097{
1098 if (ctx)
1099 auditsc_get_stamp(ctx, t, serial);
1100 else {
1101 *t = CURRENT_TIME;
1102 *serial = audit_serial();
1103 }
1104}
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
1129 int type)
1130{
1131 struct audit_buffer *ab = NULL;
1132 struct timespec t;
1133 unsigned int serial;
1134 int reserve;
1135 unsigned long timeout_start = jiffies;
1136
1137 if (!audit_initialized)
1138 return NULL;
1139
1140 if (unlikely(audit_filter_type(type)))
1141 return NULL;
1142
1143 if (gfp_mask & __GFP_WAIT)
1144 reserve = 0;
1145 else
1146 reserve = 5;
1147
1148
1149 while (audit_backlog_limit
1150 && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
1151 if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time
1152 && time_before(jiffies, timeout_start + audit_backlog_wait_time)) {
1153
1154
1155 DECLARE_WAITQUEUE(wait, current);
1156 set_current_state(TASK_INTERRUPTIBLE);
1157 add_wait_queue(&audit_backlog_wait, &wait);
1158
1159 if (audit_backlog_limit &&
1160 skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
1161 schedule_timeout(timeout_start + audit_backlog_wait_time - jiffies);
1162
1163 __set_current_state(TASK_RUNNING);
1164 remove_wait_queue(&audit_backlog_wait, &wait);
1165 continue;
1166 }
1167 if (audit_rate_check())
1168 printk(KERN_WARNING
1169 "audit: audit_backlog=%d > "
1170 "audit_backlog_limit=%d\n",
1171 skb_queue_len(&audit_skb_queue),
1172 audit_backlog_limit);
1173 audit_log_lost("backlog limit exceeded");
1174 audit_backlog_wait_time = audit_backlog_wait_overflow;
1175 wake_up(&audit_backlog_wait);
1176 return NULL;
1177 }
1178
1179 ab = audit_buffer_alloc(ctx, gfp_mask, type);
1180 if (!ab) {
1181 audit_log_lost("out of memory in audit_log_start");
1182 return NULL;
1183 }
1184
1185 audit_get_stamp(ab->ctx, &t, &serial);
1186
1187 audit_log_format(ab, "audit(%lu.%03lu:%u): ",
1188 t.tv_sec, t.tv_nsec/1000000, serial);
1189 return ab;
1190}
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200static inline int audit_expand(struct audit_buffer *ab, int extra)
1201{
1202 struct sk_buff *skb = ab->skb;
1203 int ret = pskb_expand_head(skb, skb_headroom(skb), extra,
1204 ab->gfp_mask);
1205 if (ret < 0) {
1206 audit_log_lost("out of memory in audit_expand");
1207 return 0;
1208 }
1209 return skb_tailroom(skb);
1210}
1211
1212
1213
1214
1215
1216
1217
1218static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
1219 va_list args)
1220{
1221 int len, avail;
1222 struct sk_buff *skb;
1223 va_list args2;
1224
1225 if (!ab)
1226 return;
1227
1228 BUG_ON(!ab->skb);
1229 skb = ab->skb;
1230 avail = skb_tailroom(skb);
1231 if (avail == 0) {
1232 avail = audit_expand(ab, AUDIT_BUFSIZ);
1233 if (!avail)
1234 goto out;
1235 }
1236 va_copy(args2, args);
1237 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args);
1238 if (len >= avail) {
1239
1240
1241
1242 avail = audit_expand(ab,
1243 max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
1244 if (!avail)
1245 goto out;
1246 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2);
1247 }
1248 if (len > 0)
1249 skb_put(skb, len);
1250out:
1251 return;
1252}
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
1263{
1264 va_list args;
1265
1266 if (!ab)
1267 return;
1268 va_start(args, fmt);
1269 audit_log_vformat(ab, fmt, args);
1270 va_end(args);
1271}
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf,
1285 size_t len)
1286{
1287 int i, avail, new_len;
1288 unsigned char *ptr;
1289 struct sk_buff *skb;
1290 static const unsigned char *hex = "0123456789ABCDEF";
1291
1292 if (!ab)
1293 return;
1294
1295 BUG_ON(!ab->skb);
1296 skb = ab->skb;
1297 avail = skb_tailroom(skb);
1298 new_len = len<<1;
1299 if (new_len >= avail) {
1300
1301 new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1);
1302 avail = audit_expand(ab, new_len);
1303 if (!avail)
1304 return;
1305 }
1306
1307 ptr = skb_tail_pointer(skb);
1308 for (i=0; i<len; i++) {
1309 *ptr++ = hex[(buf[i] & 0xF0)>>4];
1310 *ptr++ = hex[buf[i] & 0x0F];
1311 }
1312 *ptr = 0;
1313 skb_put(skb, len << 1);
1314}
1315
1316
1317
1318
1319
1320static void audit_log_n_string(struct audit_buffer *ab, size_t slen,
1321 const char *string)
1322{
1323 int avail, new_len;
1324 unsigned char *ptr;
1325 struct sk_buff *skb;
1326
1327 if (!ab)
1328 return;
1329
1330 BUG_ON(!ab->skb);
1331 skb = ab->skb;
1332 avail = skb_tailroom(skb);
1333 new_len = slen + 3;
1334 if (new_len > avail) {
1335 avail = audit_expand(ab, new_len);
1336 if (!avail)
1337 return;
1338 }
1339 ptr = skb_tail_pointer(skb);
1340 *ptr++ = '"';
1341 memcpy(ptr, string, slen);
1342 ptr += slen;
1343 *ptr++ = '"';
1344 *ptr = 0;
1345 skb_put(skb, slen + 2);
1346}
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362const char *audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len,
1363 const char *string)
1364{
1365 const unsigned char *p;
1366
1367 for (p = string; p < (const unsigned char *)string + len && *p; p++) {
1368 if (*p == '"' || *p < 0x21 || *p > 0x7f) {
1369 audit_log_hex(ab, string, len);
1370 return string + len + 1;
1371 }
1372 }
1373 audit_log_n_string(ab, len, string);
1374 return p + 1;
1375}
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385const char *audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
1386{
1387 return audit_log_n_untrustedstring(ab, strlen(string), string);
1388}
1389
1390
1391void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
1392 struct dentry *dentry, struct vfsmount *vfsmnt)
1393{
1394 char *p, *path;
1395
1396 if (prefix)
1397 audit_log_format(ab, " %s", prefix);
1398
1399
1400 path = kmalloc(PATH_MAX+11, ab->gfp_mask);
1401 if (!path) {
1402 audit_log_format(ab, "<no memory>");
1403 return;
1404 }
1405 p = d_path(dentry, vfsmnt, path, PATH_MAX+11);
1406 if (IS_ERR(p)) {
1407
1408 audit_log_format(ab, "<too long>");
1409 } else
1410 audit_log_untrustedstring(ab, p);
1411 kfree(path);
1412}
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423void audit_log_end(struct audit_buffer *ab)
1424{
1425 if (!ab)
1426 return;
1427 if (!audit_rate_check()) {
1428 audit_log_lost("rate limit exceeded");
1429 } else {
1430 if (audit_pid) {
1431 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
1432 nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
1433 skb_queue_tail(&audit_skb_queue, ab->skb);
1434 ab->skb = NULL;
1435 wake_up_interruptible(&kauditd_wait);
1436 } else {
1437 printk(KERN_NOTICE "%s\n", ab->skb->data + NLMSG_SPACE(0));
1438 }
1439 }
1440 audit_buffer_free(ab);
1441}
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
1456 const char *fmt, ...)
1457{
1458 struct audit_buffer *ab;
1459 va_list args;
1460
1461 ab = audit_log_start(ctx, gfp_mask, type);
1462 if (ab) {
1463 va_start(args, fmt);
1464 audit_log_vformat(ab, fmt, args);
1465 va_end(args);
1466 audit_log_end(ab);
1467 }
1468}
1469
1470EXPORT_SYMBOL(audit_log_start);
1471EXPORT_SYMBOL(audit_log_end);
1472EXPORT_SYMBOL(audit_log_format);
1473EXPORT_SYMBOL(audit_log);
1474