1 /* audit.c -- Auditing support
2 * Gateway between the kernel (e.g., selinux) and the user-space audit daemon.
3 * System-call specific features have moved to auditsc.c
5 * Copyright 2003-2007 Red Hat Inc., Durham, North Carolina.
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.
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.
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
22 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
24 * Goals: 1) Integrate fully with Security Modules.
25 * 2) Minimal run-time overhead:
26 * a) Minimal when syscall auditing is disabled (audit_enable=0).
27 * b) Small when syscall auditing is enabled and no audit record
28 * is generated (defer as much work as possible to record
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
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.
41 * Example user-space utilities: http://people.redhat.com/sgrubb/audit/
44 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
46 #include <linux/file.h>
47 #include <linux/init.h>
48 #include <linux/types.h>
49 #include <linux/atomic.h>
51 #include <linux/export.h>
52 #include <linux/slab.h>
53 #include <linux/err.h>
54 #include <linux/kthread.h>
55 #include <linux/kernel.h>
56 #include <linux/syscalls.h>
58 #include <linux/audit.h>
61 #include <net/netlink.h>
62 #include <linux/skbuff.h>
63 #ifdef CONFIG_SECURITY
64 #include <linux/security.h>
66 #include <linux/freezer.h>
67 #include <linux/tty.h>
68 #include <linux/pid_namespace.h>
69 #include <net/netns/generic.h>
73 /* No auditing will take place until audit_initialized == AUDIT_INITIALIZED.
74 * (Initialization happens after skb_init is called.) */
75 #define AUDIT_DISABLED -1
76 #define AUDIT_UNINITIALIZED 0
77 #define AUDIT_INITIALIZED 1
78 static int audit_initialized
;
82 #define AUDIT_LOCKED 2
84 u32 audit_ever_enabled
;
86 EXPORT_SYMBOL_GPL(audit_enabled
);
88 /* Default state when kernel boots without any parameters. */
89 static u32 audit_default
;
91 /* If auditing cannot proceed, audit_failure selects what happens. */
92 static u32 audit_failure
= AUDIT_FAIL_PRINTK
;
95 * If audit records are to be written to the netlink socket, audit_pid
96 * contains the pid of the auditd process and audit_nlk_portid contains
97 * the portid to use to send netlink messages to that process.
100 static __u32 audit_nlk_portid
;
102 /* If audit_rate_limit is non-zero, limit the rate of sending audit records
103 * to that number per second. This prevents DoS attacks, but results in
104 * audit records being dropped. */
105 static u32 audit_rate_limit
;
107 /* Number of outstanding audit_buffers allowed.
108 * When set to zero, this means unlimited. */
109 static u32 audit_backlog_limit
= 64;
110 #define AUDIT_BACKLOG_WAIT_TIME (60 * HZ)
111 static u32 audit_backlog_wait_time_master
= AUDIT_BACKLOG_WAIT_TIME
;
112 static u32 audit_backlog_wait_time
= AUDIT_BACKLOG_WAIT_TIME
;
113 static u32 audit_backlog_wait_overflow
= 0;
115 /* The identity of the user shutting down the audit system. */
116 kuid_t audit_sig_uid
= INVALID_UID
;
117 pid_t audit_sig_pid
= -1;
118 u32 audit_sig_sid
= 0;
120 /* Records can be lost in several ways:
121 0) [suppressed in audit_alloc]
122 1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
123 2) out of memory in audit_log_move [alloc_skb]
124 3) suppressed due to audit_rate_limit
125 4) suppressed due to audit_backlog_limit
127 static atomic_t audit_lost
= ATOMIC_INIT(0);
129 /* The netlink socket. */
130 static struct sock
*audit_sock
;
131 static int audit_net_id
;
133 /* Hash for inode-based rules */
134 struct list_head audit_inode_hash
[AUDIT_INODE_BUCKETS
];
136 /* The audit_freelist is a list of pre-allocated audit buffers (if more
137 * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
138 * being placed on the freelist). */
139 static DEFINE_SPINLOCK(audit_freelist_lock
);
140 static int audit_freelist_count
;
141 static LIST_HEAD(audit_freelist
);
143 static struct sk_buff_head audit_skb_queue
;
144 /* queue of skbs to send to auditd when/if it comes back */
145 static struct sk_buff_head audit_skb_hold_queue
;
146 static struct task_struct
*kauditd_task
;
147 static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait
);
148 static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait
);
150 static struct audit_features af
= {.vers
= AUDIT_FEATURE_VERSION
,
155 static char *audit_feature_names
[2] = {
156 "only_unset_loginuid",
157 "loginuid_immutable",
161 /* Serialize requests from userspace. */
162 DEFINE_MUTEX(audit_cmd_mutex
);
164 /* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
165 * audit records. Since printk uses a 1024 byte buffer, this buffer
166 * should be at least that large. */
167 #define AUDIT_BUFSIZ 1024
169 /* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the
170 * audit_freelist. Doing so eliminates many kmalloc/kfree calls. */
171 #define AUDIT_MAXFREE (2*NR_CPUS)
173 /* The audit_buffer is used when formatting an audit record. The caller
174 * locks briefly to get the record off the freelist or to allocate the
175 * buffer, and locks briefly to send the buffer to the netlink layer or
176 * to place it on a transmit queue. Multiple audit_buffers can be in
177 * use simultaneously. */
178 struct audit_buffer
{
179 struct list_head list
;
180 struct sk_buff
*skb
; /* formatted skb ready to send */
181 struct audit_context
*ctx
; /* NULL or associated context */
191 static void audit_set_portid(struct audit_buffer
*ab
, __u32 portid
)
194 struct nlmsghdr
*nlh
= nlmsg_hdr(ab
->skb
);
195 nlh
->nlmsg_pid
= portid
;
199 void audit_panic(const char *message
)
201 switch (audit_failure
) {
202 case AUDIT_FAIL_SILENT
:
204 case AUDIT_FAIL_PRINTK
:
205 if (printk_ratelimit())
206 pr_err("%s\n", message
);
208 case AUDIT_FAIL_PANIC
:
209 /* test audit_pid since printk is always losey, why bother? */
211 panic("audit: %s\n", message
);
216 static inline int audit_rate_check(void)
218 static unsigned long last_check
= 0;
219 static int messages
= 0;
220 static DEFINE_SPINLOCK(lock
);
223 unsigned long elapsed
;
226 if (!audit_rate_limit
) return 1;
228 spin_lock_irqsave(&lock
, flags
);
229 if (++messages
< audit_rate_limit
) {
233 elapsed
= now
- last_check
;
240 spin_unlock_irqrestore(&lock
, flags
);
246 * audit_log_lost - conditionally log lost audit message event
247 * @message: the message stating reason for lost audit message
249 * Emit at least 1 message per second, even if audit_rate_check is
251 * Always increment the lost messages counter.
253 void audit_log_lost(const char *message
)
255 static unsigned long last_msg
= 0;
256 static DEFINE_SPINLOCK(lock
);
261 atomic_inc(&audit_lost
);
263 print
= (audit_failure
== AUDIT_FAIL_PANIC
|| !audit_rate_limit
);
266 spin_lock_irqsave(&lock
, flags
);
268 if (now
- last_msg
> HZ
) {
272 spin_unlock_irqrestore(&lock
, flags
);
276 if (printk_ratelimit())
277 pr_warn("audit_lost=%u audit_rate_limit=%u audit_backlog_limit=%u\n",
278 atomic_read(&audit_lost
),
280 audit_backlog_limit
);
281 audit_panic(message
);
285 static int audit_log_config_change(char *function_name
, u32
new, u32 old
,
288 struct audit_buffer
*ab
;
291 ab
= audit_log_start(NULL
, GFP_KERNEL
, AUDIT_CONFIG_CHANGE
);
294 audit_log_format(ab
, "%s=%u old=%u", function_name
, new, old
);
295 audit_log_session_info(ab
);
296 rc
= audit_log_task_context(ab
);
298 allow_changes
= 0; /* Something weird, deny request */
299 audit_log_format(ab
, " res=%d", allow_changes
);
304 static int audit_do_config_change(char *function_name
, u32
*to_change
, u32
new)
306 int allow_changes
, rc
= 0;
307 u32 old
= *to_change
;
309 /* check if we are locked */
310 if (audit_enabled
== AUDIT_LOCKED
)
315 if (audit_enabled
!= AUDIT_OFF
) {
316 rc
= audit_log_config_change(function_name
, new, old
, allow_changes
);
321 /* If we are allowed, make the change */
322 if (allow_changes
== 1)
324 /* Not allowed, update reason */
330 static int audit_set_rate_limit(u32 limit
)
332 return audit_do_config_change("audit_rate_limit", &audit_rate_limit
, limit
);
335 static int audit_set_backlog_limit(u32 limit
)
337 return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit
, limit
);
340 static int audit_set_backlog_wait_time(u32 timeout
)
342 return audit_do_config_change("audit_backlog_wait_time",
343 &audit_backlog_wait_time_master
, timeout
);
346 static int audit_set_enabled(u32 state
)
349 if (state
> AUDIT_LOCKED
)
352 rc
= audit_do_config_change("audit_enabled", &audit_enabled
, state
);
354 audit_ever_enabled
|= !!state
;
359 static int audit_set_failure(u32 state
)
361 if (state
!= AUDIT_FAIL_SILENT
362 && state
!= AUDIT_FAIL_PRINTK
363 && state
!= AUDIT_FAIL_PANIC
)
366 return audit_do_config_change("audit_failure", &audit_failure
, state
);
370 * Queue skbs to be sent to auditd when/if it comes back. These skbs should
371 * already have been sent via prink/syslog and so if these messages are dropped
372 * it is not a huge concern since we already passed the audit_log_lost()
373 * notification and stuff. This is just nice to get audit messages during
374 * boot before auditd is running or messages generated while auditd is stopped.
375 * This only holds messages is audit_default is set, aka booting with audit=1
376 * or building your kernel that way.
378 static void audit_hold_skb(struct sk_buff
*skb
)
381 (!audit_backlog_limit
||
382 skb_queue_len(&audit_skb_hold_queue
) < audit_backlog_limit
))
383 skb_queue_tail(&audit_skb_hold_queue
, skb
);
389 * For one reason or another this nlh isn't getting delivered to the userspace
390 * audit daemon, just send it to printk.
392 static void audit_printk_skb(struct sk_buff
*skb
)
394 struct nlmsghdr
*nlh
= nlmsg_hdr(skb
);
395 char *data
= nlmsg_data(nlh
);
397 if (nlh
->nlmsg_type
!= AUDIT_EOE
) {
398 if (printk_ratelimit())
399 pr_notice("type=%d %s\n", nlh
->nlmsg_type
, data
);
401 audit_log_lost("printk limit exceeded");
407 static void kauditd_send_skb(struct sk_buff
*skb
)
411 #define AUDITD_RETRIES 5
414 /* take a reference in case we can't send it and we want to hold it */
416 err
= netlink_unicast(audit_sock
, skb
, audit_nlk_portid
, 0);
418 pr_err("netlink_unicast sending to audit_pid=%d returned error: %d\n",
421 if (err
== -ECONNREFUSED
|| err
== -EPERM
422 || ++attempts
>= AUDITD_RETRIES
) {
425 snprintf(s
, sizeof(s
), "audit_pid=%d reset", audit_pid
);
430 pr_warn("re-scheduling(#%d) write to audit_pid=%d\n",
431 attempts
, audit_pid
);
432 set_current_state(TASK_INTERRUPTIBLE
);
434 __set_current_state(TASK_RUNNING
);
438 /* we might get lucky and get this in the next auditd */
441 /* drop the extra reference if sent ok */
446 * kauditd_send_multicast_skb - send the skb to multicast userspace listeners
448 * This function doesn't consume an skb as might be expected since it has to
451 static void kauditd_send_multicast_skb(struct sk_buff
*skb
, gfp_t gfp_mask
)
453 struct sk_buff
*copy
;
454 struct audit_net
*aunet
= net_generic(&init_net
, audit_net_id
);
455 struct sock
*sock
= aunet
->nlsk
;
457 if (!netlink_has_listeners(sock
, AUDIT_NLGRP_READLOG
))
461 * The seemingly wasteful skb_copy() rather than bumping the refcount
462 * using skb_get() is necessary because non-standard mods are made to
463 * the skb by the original kaudit unicast socket send routine. The
464 * existing auditd daemon assumes this breakage. Fixing this would
465 * require co-ordinating a change in the established protocol between
466 * the kaudit kernel subsystem and the auditd userspace code. There is
467 * no reason for new multicast clients to continue with this
470 copy
= skb_copy(skb
, gfp_mask
);
474 nlmsg_multicast(sock
, copy
, 0, AUDIT_NLGRP_READLOG
, gfp_mask
);
478 * flush_hold_queue - empty the hold queue if auditd appears
480 * If auditd just started, drain the queue of messages already
481 * sent to syslog/printk. Remember loss here is ok. We already
482 * called audit_log_lost() if it didn't go out normally. so the
483 * race between the skb_dequeue and the next check for audit_pid
486 * If you ever find kauditd to be too slow we can get a perf win
487 * by doing our own locking and keeping better track if there
488 * are messages in this queue. I don't see the need now, but
489 * in 5 years when I want to play with this again I'll see this
490 * note and still have no friggin idea what i'm thinking today.
492 static void flush_hold_queue(void)
496 if (!audit_default
|| !audit_pid
)
499 skb
= skb_dequeue(&audit_skb_hold_queue
);
503 while (skb
&& audit_pid
) {
504 kauditd_send_skb(skb
);
505 skb
= skb_dequeue(&audit_skb_hold_queue
);
509 * if auditd just disappeared but we
510 * dequeued an skb we need to drop ref
516 static int kauditd_thread(void *dummy
)
519 while (!kthread_should_stop()) {
524 skb
= skb_dequeue(&audit_skb_queue
);
527 if (skb_queue_len(&audit_skb_queue
) <= audit_backlog_limit
)
528 wake_up(&audit_backlog_wait
);
530 kauditd_send_skb(skb
);
532 audit_printk_skb(skb
);
536 wait_event_freezable(kauditd_wait
, skb_queue_len(&audit_skb_queue
));
541 int audit_send_list(void *_dest
)
543 struct audit_netlink_list
*dest
= _dest
;
545 struct net
*net
= dest
->net
;
546 struct audit_net
*aunet
= net_generic(net
, audit_net_id
);
548 /* wait for parent to finish and send an ACK */
549 mutex_lock(&audit_cmd_mutex
);
550 mutex_unlock(&audit_cmd_mutex
);
552 while ((skb
= __skb_dequeue(&dest
->q
)) != NULL
)
553 netlink_unicast(aunet
->nlsk
, skb
, dest
->portid
, 0);
561 struct sk_buff
*audit_make_reply(__u32 portid
, int seq
, int type
, int done
,
562 int multi
, const void *payload
, int size
)
565 struct nlmsghdr
*nlh
;
567 int flags
= multi
? NLM_F_MULTI
: 0;
568 int t
= done
? NLMSG_DONE
: type
;
570 skb
= nlmsg_new(size
, GFP_KERNEL
);
574 nlh
= nlmsg_put(skb
, portid
, seq
, t
, size
, flags
);
577 data
= nlmsg_data(nlh
);
578 memcpy(data
, payload
, size
);
586 static int audit_send_reply_thread(void *arg
)
588 struct audit_reply
*reply
= (struct audit_reply
*)arg
;
589 struct net
*net
= reply
->net
;
590 struct audit_net
*aunet
= net_generic(net
, audit_net_id
);
592 mutex_lock(&audit_cmd_mutex
);
593 mutex_unlock(&audit_cmd_mutex
);
595 /* Ignore failure. It'll only happen if the sender goes away,
596 because our timeout is set to infinite. */
597 netlink_unicast(aunet
->nlsk
, reply
->skb
, reply
->portid
, 0);
603 * audit_send_reply - send an audit reply message via netlink
604 * @request_skb: skb of request we are replying to (used to target the reply)
605 * @seq: sequence number
606 * @type: audit message type
607 * @done: done (last) flag
608 * @multi: multi-part message flag
609 * @payload: payload data
610 * @size: payload size
612 * Allocates an skb, builds the netlink message, and sends it to the port id.
613 * No failure notifications.
615 static void audit_send_reply(struct sk_buff
*request_skb
, int seq
, int type
, int done
,
616 int multi
, const void *payload
, int size
)
618 u32 portid
= NETLINK_CB(request_skb
).portid
;
619 struct net
*net
= sock_net(NETLINK_CB(request_skb
).sk
);
621 struct task_struct
*tsk
;
622 struct audit_reply
*reply
= kmalloc(sizeof(struct audit_reply
),
628 skb
= audit_make_reply(portid
, seq
, type
, done
, multi
, payload
, size
);
632 reply
->net
= get_net(net
);
633 reply
->portid
= portid
;
636 tsk
= kthread_run(audit_send_reply_thread
, reply
, "audit_send_reply");
645 * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
648 static int audit_netlink_ok(struct sk_buff
*skb
, u16 msg_type
)
652 /* Only support initial user namespace for now. */
654 * We return ECONNREFUSED because it tricks userspace into thinking
655 * that audit was not configured into the kernel. Lots of users
656 * configure their PAM stack (because that's what the distro does)
657 * to reject login if unable to send messages to audit. If we return
658 * ECONNREFUSED the PAM stack thinks the kernel does not have audit
659 * configured in and will let login proceed. If we return EPERM
660 * userspace will reject all logins. This should be removed when we
661 * support non init namespaces!!
663 if (current_user_ns() != &init_user_ns
)
664 return -ECONNREFUSED
;
673 case AUDIT_GET_FEATURE
:
674 case AUDIT_SET_FEATURE
:
675 case AUDIT_LIST_RULES
:
678 case AUDIT_SIGNAL_INFO
:
682 case AUDIT_MAKE_EQUIV
:
683 /* Only support auditd and auditctl in initial pid namespace
685 if (task_active_pid_ns(current
) != &init_pid_ns
)
688 if (!netlink_capable(skb
, CAP_AUDIT_CONTROL
))
692 case AUDIT_FIRST_USER_MSG
... AUDIT_LAST_USER_MSG
:
693 case AUDIT_FIRST_USER_MSG2
... AUDIT_LAST_USER_MSG2
:
694 if (!netlink_capable(skb
, CAP_AUDIT_WRITE
))
697 default: /* bad msg */
704 static void audit_log_common_recv_msg(struct audit_buffer
**ab
, u16 msg_type
)
706 uid_t uid
= from_kuid(&init_user_ns
, current_uid());
707 pid_t pid
= task_tgid_nr(current
);
709 if (!audit_enabled
&& msg_type
!= AUDIT_USER_AVC
) {
714 *ab
= audit_log_start(NULL
, GFP_KERNEL
, msg_type
);
717 audit_log_format(*ab
, "pid=%d uid=%u", pid
, uid
);
718 audit_log_session_info(*ab
);
719 audit_log_task_context(*ab
);
722 int is_audit_feature_set(int i
)
724 return af
.features
& AUDIT_FEATURE_TO_MASK(i
);
728 static int audit_get_feature(struct sk_buff
*skb
)
732 seq
= nlmsg_hdr(skb
)->nlmsg_seq
;
734 audit_send_reply(skb
, seq
, AUDIT_GET_FEATURE
, 0, 0, &af
, sizeof(af
));
739 static void audit_log_feature_change(int which
, u32 old_feature
, u32 new_feature
,
740 u32 old_lock
, u32 new_lock
, int res
)
742 struct audit_buffer
*ab
;
744 if (audit_enabled
== AUDIT_OFF
)
747 ab
= audit_log_start(NULL
, GFP_KERNEL
, AUDIT_FEATURE_CHANGE
);
748 audit_log_task_info(ab
, current
);
749 audit_log_format(ab
, " feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d",
750 audit_feature_names
[which
], !!old_feature
, !!new_feature
,
751 !!old_lock
, !!new_lock
, res
);
755 static int audit_set_feature(struct sk_buff
*skb
)
757 struct audit_features
*uaf
;
760 BUILD_BUG_ON(AUDIT_LAST_FEATURE
+ 1 > ARRAY_SIZE(audit_feature_names
));
761 uaf
= nlmsg_data(nlmsg_hdr(skb
));
763 /* if there is ever a version 2 we should handle that here */
765 for (i
= 0; i
<= AUDIT_LAST_FEATURE
; i
++) {
766 u32 feature
= AUDIT_FEATURE_TO_MASK(i
);
767 u32 old_feature
, new_feature
, old_lock
, new_lock
;
769 /* if we are not changing this feature, move along */
770 if (!(feature
& uaf
->mask
))
773 old_feature
= af
.features
& feature
;
774 new_feature
= uaf
->features
& feature
;
775 new_lock
= (uaf
->lock
| af
.lock
) & feature
;
776 old_lock
= af
.lock
& feature
;
778 /* are we changing a locked feature? */
779 if (old_lock
&& (new_feature
!= old_feature
)) {
780 audit_log_feature_change(i
, old_feature
, new_feature
,
781 old_lock
, new_lock
, 0);
785 /* nothing invalid, do the changes */
786 for (i
= 0; i
<= AUDIT_LAST_FEATURE
; i
++) {
787 u32 feature
= AUDIT_FEATURE_TO_MASK(i
);
788 u32 old_feature
, new_feature
, old_lock
, new_lock
;
790 /* if we are not changing this feature, move along */
791 if (!(feature
& uaf
->mask
))
794 old_feature
= af
.features
& feature
;
795 new_feature
= uaf
->features
& feature
;
796 old_lock
= af
.lock
& feature
;
797 new_lock
= (uaf
->lock
| af
.lock
) & feature
;
799 if (new_feature
!= old_feature
)
800 audit_log_feature_change(i
, old_feature
, new_feature
,
801 old_lock
, new_lock
, 1);
804 af
.features
|= feature
;
806 af
.features
&= ~feature
;
813 static int audit_receive_msg(struct sk_buff
*skb
, struct nlmsghdr
*nlh
)
818 struct audit_buffer
*ab
;
819 u16 msg_type
= nlh
->nlmsg_type
;
820 struct audit_sig_info
*sig_data
;
824 err
= audit_netlink_ok(skb
, msg_type
);
828 /* As soon as there's any sign of userspace auditd,
829 * start kauditd to talk to it */
831 kauditd_task
= kthread_run(kauditd_thread
, NULL
, "kauditd");
832 if (IS_ERR(kauditd_task
)) {
833 err
= PTR_ERR(kauditd_task
);
838 seq
= nlh
->nlmsg_seq
;
839 data
= nlmsg_data(nlh
);
843 struct audit_status s
;
844 memset(&s
, 0, sizeof(s
));
845 s
.enabled
= audit_enabled
;
846 s
.failure
= audit_failure
;
848 s
.rate_limit
= audit_rate_limit
;
849 s
.backlog_limit
= audit_backlog_limit
;
850 s
.lost
= atomic_read(&audit_lost
);
851 s
.backlog
= skb_queue_len(&audit_skb_queue
);
852 s
.feature_bitmap
= AUDIT_FEATURE_BITMAP_ALL
;
853 s
.backlog_wait_time
= audit_backlog_wait_time_master
;
854 audit_send_reply(skb
, seq
, AUDIT_GET
, 0, 0, &s
, sizeof(s
));
858 struct audit_status s
;
859 memset(&s
, 0, sizeof(s
));
860 /* guard against past and future API changes */
861 memcpy(&s
, data
, min_t(size_t, sizeof(s
), nlmsg_len(nlh
)));
862 if (s
.mask
& AUDIT_STATUS_ENABLED
) {
863 err
= audit_set_enabled(s
.enabled
);
867 if (s
.mask
& AUDIT_STATUS_FAILURE
) {
868 err
= audit_set_failure(s
.failure
);
872 if (s
.mask
& AUDIT_STATUS_PID
) {
873 /* NOTE: we are using task_tgid_vnr() below because
874 * the s.pid value is relative to the namespace
875 * of the caller; at present this doesn't matter
876 * much since you can really only run auditd
877 * from the initial pid namespace, but something
878 * to keep in mind if this changes */
881 if ((!new_pid
) && (task_tgid_vnr(current
) != audit_pid
))
883 if (audit_enabled
!= AUDIT_OFF
)
884 audit_log_config_change("audit_pid", new_pid
, audit_pid
, 1);
886 audit_nlk_portid
= NETLINK_CB(skb
).portid
;
887 audit_sock
= skb
->sk
;
889 if (s
.mask
& AUDIT_STATUS_RATE_LIMIT
) {
890 err
= audit_set_rate_limit(s
.rate_limit
);
894 if (s
.mask
& AUDIT_STATUS_BACKLOG_LIMIT
) {
895 err
= audit_set_backlog_limit(s
.backlog_limit
);
899 if (s
.mask
& AUDIT_STATUS_BACKLOG_WAIT_TIME
) {
900 if (sizeof(s
) > (size_t)nlh
->nlmsg_len
)
902 if (s
.backlog_wait_time
> 10*AUDIT_BACKLOG_WAIT_TIME
)
904 err
= audit_set_backlog_wait_time(s
.backlog_wait_time
);
910 case AUDIT_GET_FEATURE
:
911 err
= audit_get_feature(skb
);
915 case AUDIT_SET_FEATURE
:
916 err
= audit_set_feature(skb
);
921 case AUDIT_FIRST_USER_MSG
... AUDIT_LAST_USER_MSG
:
922 case AUDIT_FIRST_USER_MSG2
... AUDIT_LAST_USER_MSG2
:
923 if (!audit_enabled
&& msg_type
!= AUDIT_USER_AVC
)
926 err
= audit_filter_user(msg_type
);
927 if (err
== 1) { /* match or error */
929 if (msg_type
== AUDIT_USER_TTY
) {
930 err
= tty_audit_push_current();
934 mutex_unlock(&audit_cmd_mutex
);
935 audit_log_common_recv_msg(&ab
, msg_type
);
936 if (msg_type
!= AUDIT_USER_TTY
)
937 audit_log_format(ab
, " msg='%.*s'",
938 AUDIT_MESSAGE_TEXT_MAX
,
943 audit_log_format(ab
, " data=");
944 size
= nlmsg_len(nlh
);
946 ((unsigned char *)data
)[size
- 1] == '\0')
948 audit_log_n_untrustedstring(ab
, data
, size
);
950 audit_set_portid(ab
, NETLINK_CB(skb
).portid
);
952 mutex_lock(&audit_cmd_mutex
);
957 if (nlmsg_len(nlh
) < sizeof(struct audit_rule_data
))
959 if (audit_enabled
== AUDIT_LOCKED
) {
960 audit_log_common_recv_msg(&ab
, AUDIT_CONFIG_CHANGE
);
961 audit_log_format(ab
, " audit_enabled=%d res=0", audit_enabled
);
965 err
= audit_rule_change(msg_type
, NETLINK_CB(skb
).portid
,
966 seq
, data
, nlmsg_len(nlh
));
968 case AUDIT_LIST_RULES
:
969 err
= audit_list_rules_send(skb
, seq
);
973 audit_log_common_recv_msg(&ab
, AUDIT_CONFIG_CHANGE
);
974 audit_log_format(ab
, " op=trim res=1");
977 case AUDIT_MAKE_EQUIV
: {
980 size_t msglen
= nlmsg_len(nlh
);
984 if (msglen
< 2 * sizeof(u32
))
986 memcpy(sizes
, bufp
, 2 * sizeof(u32
));
987 bufp
+= 2 * sizeof(u32
);
988 msglen
-= 2 * sizeof(u32
);
989 old
= audit_unpack_string(&bufp
, &msglen
, sizes
[0]);
994 new = audit_unpack_string(&bufp
, &msglen
, sizes
[1]);
1000 /* OK, here comes... */
1001 err
= audit_tag_tree(old
, new);
1003 audit_log_common_recv_msg(&ab
, AUDIT_CONFIG_CHANGE
);
1005 audit_log_format(ab
, " op=make_equiv old=");
1006 audit_log_untrustedstring(ab
, old
);
1007 audit_log_format(ab
, " new=");
1008 audit_log_untrustedstring(ab
, new);
1009 audit_log_format(ab
, " res=%d", !err
);
1015 case AUDIT_SIGNAL_INFO
:
1017 if (audit_sig_sid
) {
1018 err
= security_secid_to_secctx(audit_sig_sid
, &ctx
, &len
);
1022 sig_data
= kmalloc(sizeof(*sig_data
) + len
, GFP_KERNEL
);
1025 security_release_secctx(ctx
, len
);
1028 sig_data
->uid
= from_kuid(&init_user_ns
, audit_sig_uid
);
1029 sig_data
->pid
= audit_sig_pid
;
1030 if (audit_sig_sid
) {
1031 memcpy(sig_data
->ctx
, ctx
, len
);
1032 security_release_secctx(ctx
, len
);
1034 audit_send_reply(skb
, seq
, AUDIT_SIGNAL_INFO
, 0, 0,
1035 sig_data
, sizeof(*sig_data
) + len
);
1038 case AUDIT_TTY_GET
: {
1039 struct audit_tty_status s
;
1040 struct task_struct
*tsk
= current
;
1042 spin_lock(&tsk
->sighand
->siglock
);
1043 s
.enabled
= tsk
->signal
->audit_tty
;
1044 s
.log_passwd
= tsk
->signal
->audit_tty_log_passwd
;
1045 spin_unlock(&tsk
->sighand
->siglock
);
1047 audit_send_reply(skb
, seq
, AUDIT_TTY_GET
, 0, 0, &s
, sizeof(s
));
1050 case AUDIT_TTY_SET
: {
1051 struct audit_tty_status s
, old
;
1052 struct task_struct
*tsk
= current
;
1053 struct audit_buffer
*ab
;
1055 memset(&s
, 0, sizeof(s
));
1056 /* guard against past and future API changes */
1057 memcpy(&s
, data
, min_t(size_t, sizeof(s
), nlmsg_len(nlh
)));
1058 /* check if new data is valid */
1059 if ((s
.enabled
!= 0 && s
.enabled
!= 1) ||
1060 (s
.log_passwd
!= 0 && s
.log_passwd
!= 1))
1063 spin_lock(&tsk
->sighand
->siglock
);
1064 old
.enabled
= tsk
->signal
->audit_tty
;
1065 old
.log_passwd
= tsk
->signal
->audit_tty_log_passwd
;
1067 tsk
->signal
->audit_tty
= s
.enabled
;
1068 tsk
->signal
->audit_tty_log_passwd
= s
.log_passwd
;
1070 spin_unlock(&tsk
->sighand
->siglock
);
1072 audit_log_common_recv_msg(&ab
, AUDIT_CONFIG_CHANGE
);
1073 audit_log_format(ab
, " op=tty_set old-enabled=%d new-enabled=%d"
1074 " old-log_passwd=%d new-log_passwd=%d res=%d",
1075 old
.enabled
, s
.enabled
, old
.log_passwd
,
1076 s
.log_passwd
, !err
);
1085 return err
< 0 ? err
: 0;
1089 * Get message from skb. Each message is processed by audit_receive_msg.
1090 * Malformed skbs with wrong length are discarded silently.
1092 static void audit_receive_skb(struct sk_buff
*skb
)
1094 struct nlmsghdr
*nlh
;
1096 * len MUST be signed for nlmsg_next to be able to dec it below 0
1097 * if the nlmsg_len was not aligned
1102 nlh
= nlmsg_hdr(skb
);
1105 while (nlmsg_ok(nlh
, len
)) {
1106 err
= audit_receive_msg(skb
, nlh
);
1107 /* if err or if this message says it wants a response */
1108 if (err
|| (nlh
->nlmsg_flags
& NLM_F_ACK
))
1109 netlink_ack(skb
, nlh
, err
);
1111 nlh
= nlmsg_next(nlh
, &len
);
1115 /* Receive messages from netlink socket. */
1116 static void audit_receive(struct sk_buff
*skb
)
1118 mutex_lock(&audit_cmd_mutex
);
1119 audit_receive_skb(skb
);
1120 mutex_unlock(&audit_cmd_mutex
);
1123 /* Run custom bind function on netlink socket group connect or bind requests. */
1124 static int audit_bind(struct net
*net
, int group
)
1126 if (!capable(CAP_AUDIT_READ
))
1132 static int __net_init
audit_net_init(struct net
*net
)
1134 struct netlink_kernel_cfg cfg
= {
1135 .input
= audit_receive
,
1137 .flags
= NL_CFG_F_NONROOT_RECV
,
1138 .groups
= AUDIT_NLGRP_MAX
,
1141 struct audit_net
*aunet
= net_generic(net
, audit_net_id
);
1143 aunet
->nlsk
= netlink_kernel_create(net
, NETLINK_AUDIT
, &cfg
);
1144 if (aunet
->nlsk
== NULL
) {
1145 audit_panic("cannot initialize netlink socket in namespace");
1148 aunet
->nlsk
->sk_sndtimeo
= MAX_SCHEDULE_TIMEOUT
;
1152 static void __net_exit
audit_net_exit(struct net
*net
)
1154 struct audit_net
*aunet
= net_generic(net
, audit_net_id
);
1155 struct sock
*sock
= aunet
->nlsk
;
1156 if (sock
== audit_sock
) {
1161 RCU_INIT_POINTER(aunet
->nlsk
, NULL
);
1163 netlink_kernel_release(sock
);
1166 static struct pernet_operations audit_net_ops __net_initdata
= {
1167 .init
= audit_net_init
,
1168 .exit
= audit_net_exit
,
1169 .id
= &audit_net_id
,
1170 .size
= sizeof(struct audit_net
),
1173 /* Initialize audit support at boot time. */
1174 static int __init
audit_init(void)
1178 if (audit_initialized
== AUDIT_DISABLED
)
1181 pr_info("initializing netlink subsys (%s)\n",
1182 audit_default
? "enabled" : "disabled");
1183 register_pernet_subsys(&audit_net_ops
);
1185 skb_queue_head_init(&audit_skb_queue
);
1186 skb_queue_head_init(&audit_skb_hold_queue
);
1187 audit_initialized
= AUDIT_INITIALIZED
;
1188 audit_enabled
= audit_default
;
1189 audit_ever_enabled
|= !!audit_default
;
1191 audit_log(NULL
, GFP_KERNEL
, AUDIT_KERNEL
, "initialized");
1193 for (i
= 0; i
< AUDIT_INODE_BUCKETS
; i
++)
1194 INIT_LIST_HEAD(&audit_inode_hash
[i
]);
1198 __initcall(audit_init
);
1200 /* Process kernel command-line parameter at boot time. audit=0 or audit=1. */
1201 static int __init
audit_enable(char *str
)
1203 audit_default
= !!simple_strtol(str
, NULL
, 0);
1205 audit_initialized
= AUDIT_DISABLED
;
1207 pr_info("%s\n", audit_default
?
1208 "enabled (after initialization)" : "disabled (until reboot)");
1212 __setup("audit=", audit_enable
);
1214 /* Process kernel command-line parameter at boot time.
1215 * audit_backlog_limit=<n> */
1216 static int __init
audit_backlog_limit_set(char *str
)
1218 u32 audit_backlog_limit_arg
;
1220 pr_info("audit_backlog_limit: ");
1221 if (kstrtouint(str
, 0, &audit_backlog_limit_arg
)) {
1222 pr_cont("using default of %u, unable to parse %s\n",
1223 audit_backlog_limit
, str
);
1227 audit_backlog_limit
= audit_backlog_limit_arg
;
1228 pr_cont("%d\n", audit_backlog_limit
);
1232 __setup("audit_backlog_limit=", audit_backlog_limit_set
);
1234 static void audit_buffer_free(struct audit_buffer
*ab
)
1236 unsigned long flags
;
1244 spin_lock_irqsave(&audit_freelist_lock
, flags
);
1245 if (audit_freelist_count
> AUDIT_MAXFREE
)
1248 audit_freelist_count
++;
1249 list_add(&ab
->list
, &audit_freelist
);
1251 spin_unlock_irqrestore(&audit_freelist_lock
, flags
);
1254 static struct audit_buffer
* audit_buffer_alloc(struct audit_context
*ctx
,
1255 gfp_t gfp_mask
, int type
)
1257 unsigned long flags
;
1258 struct audit_buffer
*ab
= NULL
;
1259 struct nlmsghdr
*nlh
;
1261 spin_lock_irqsave(&audit_freelist_lock
, flags
);
1262 if (!list_empty(&audit_freelist
)) {
1263 ab
= list_entry(audit_freelist
.next
,
1264 struct audit_buffer
, list
);
1265 list_del(&ab
->list
);
1266 --audit_freelist_count
;
1268 spin_unlock_irqrestore(&audit_freelist_lock
, flags
);
1271 ab
= kmalloc(sizeof(*ab
), gfp_mask
);
1277 ab
->gfp_mask
= gfp_mask
;
1279 ab
->skb
= nlmsg_new(AUDIT_BUFSIZ
, gfp_mask
);
1283 nlh
= nlmsg_put(ab
->skb
, 0, 0, type
, 0, 0);
1293 audit_buffer_free(ab
);
1298 * audit_serial - compute a serial number for the audit record
1300 * Compute a serial number for the audit record. Audit records are
1301 * written to user-space as soon as they are generated, so a complete
1302 * audit record may be written in several pieces. The timestamp of the
1303 * record and this serial number are used by the user-space tools to
1304 * determine which pieces belong to the same audit record. The
1305 * (timestamp,serial) tuple is unique for each syscall and is live from
1306 * syscall entry to syscall exit.
1308 * NOTE: Another possibility is to store the formatted records off the
1309 * audit context (for those records that have a context), and emit them
1310 * all at syscall exit. However, this could delay the reporting of
1311 * significant errors until syscall exit (or never, if the system
1314 unsigned int audit_serial(void)
1316 static atomic_t serial
= ATOMIC_INIT(0);
1318 return atomic_add_return(1, &serial
);
1321 static inline void audit_get_stamp(struct audit_context
*ctx
,
1322 struct timespec
*t
, unsigned int *serial
)
1324 if (!ctx
|| !auditsc_get_stamp(ctx
, t
, serial
)) {
1326 *serial
= audit_serial();
1331 * Wait for auditd to drain the queue a little
1333 static long wait_for_auditd(long sleep_time
)
1335 DECLARE_WAITQUEUE(wait
, current
);
1336 set_current_state(TASK_UNINTERRUPTIBLE
);
1337 add_wait_queue_exclusive(&audit_backlog_wait
, &wait
);
1339 if (audit_backlog_limit
&&
1340 skb_queue_len(&audit_skb_queue
) > audit_backlog_limit
)
1341 sleep_time
= schedule_timeout(sleep_time
);
1343 __set_current_state(TASK_RUNNING
);
1344 remove_wait_queue(&audit_backlog_wait
, &wait
);
1350 * audit_log_start - obtain an audit buffer
1351 * @ctx: audit_context (may be NULL)
1352 * @gfp_mask: type of allocation
1353 * @type: audit message type
1355 * Returns audit_buffer pointer on success or NULL on error.
1357 * Obtain an audit buffer. This routine does locking to obtain the
1358 * audit buffer, but then no locking is required for calls to
1359 * audit_log_*format. If the task (ctx) is a task that is currently in a
1360 * syscall, then the syscall is marked as auditable and an audit record
1361 * will be written at syscall exit. If there is no associated task, then
1362 * task context (ctx) should be NULL.
1364 struct audit_buffer
*audit_log_start(struct audit_context
*ctx
, gfp_t gfp_mask
,
1367 struct audit_buffer
*ab
= NULL
;
1369 unsigned int uninitialized_var(serial
);
1370 int reserve
= 5; /* Allow atomic callers to go up to five
1371 entries over the normal backlog limit */
1372 unsigned long timeout_start
= jiffies
;
1374 if (audit_initialized
!= AUDIT_INITIALIZED
)
1377 if (unlikely(audit_filter_type(type
)))
1380 if (gfp_mask
& __GFP_DIRECT_RECLAIM
) {
1381 if (audit_pid
&& audit_pid
== current
->pid
)
1382 gfp_mask
&= ~__GFP_DIRECT_RECLAIM
;
1387 while (audit_backlog_limit
1388 && skb_queue_len(&audit_skb_queue
) > audit_backlog_limit
+ reserve
) {
1389 if (gfp_mask
& __GFP_DIRECT_RECLAIM
&& audit_backlog_wait_time
) {
1392 sleep_time
= timeout_start
+ audit_backlog_wait_time
- jiffies
;
1393 if (sleep_time
> 0) {
1394 sleep_time
= wait_for_auditd(sleep_time
);
1399 if (audit_rate_check() && printk_ratelimit())
1400 pr_warn("audit_backlog=%d > audit_backlog_limit=%d\n",
1401 skb_queue_len(&audit_skb_queue
),
1402 audit_backlog_limit
);
1403 audit_log_lost("backlog limit exceeded");
1404 audit_backlog_wait_time
= audit_backlog_wait_overflow
;
1405 wake_up(&audit_backlog_wait
);
1410 audit_backlog_wait_time
= audit_backlog_wait_time_master
;
1412 ab
= audit_buffer_alloc(ctx
, gfp_mask
, type
);
1414 audit_log_lost("out of memory in audit_log_start");
1418 audit_get_stamp(ab
->ctx
, &t
, &serial
);
1420 audit_log_format(ab
, "audit(%lu.%03lu:%u): ",
1421 t
.tv_sec
, t
.tv_nsec
/1000000, serial
);
1426 * audit_expand - expand skb in the audit buffer
1428 * @extra: space to add at tail of the skb
1430 * Returns 0 (no space) on failed expansion, or available space if
1433 static inline int audit_expand(struct audit_buffer
*ab
, int extra
)
1435 struct sk_buff
*skb
= ab
->skb
;
1436 int oldtail
= skb_tailroom(skb
);
1437 int ret
= pskb_expand_head(skb
, 0, extra
, ab
->gfp_mask
);
1438 int newtail
= skb_tailroom(skb
);
1441 audit_log_lost("out of memory in audit_expand");
1445 skb
->truesize
+= newtail
- oldtail
;
1450 * Format an audit message into the audit buffer. If there isn't enough
1451 * room in the audit buffer, more room will be allocated and vsnprint
1452 * will be called a second time. Currently, we assume that a printk
1453 * can't format message larger than 1024 bytes, so we don't either.
1455 static void audit_log_vformat(struct audit_buffer
*ab
, const char *fmt
,
1459 struct sk_buff
*skb
;
1467 avail
= skb_tailroom(skb
);
1469 avail
= audit_expand(ab
, AUDIT_BUFSIZ
);
1473 va_copy(args2
, args
);
1474 len
= vsnprintf(skb_tail_pointer(skb
), avail
, fmt
, args
);
1476 /* The printk buffer is 1024 bytes long, so if we get
1477 * here and AUDIT_BUFSIZ is at least 1024, then we can
1478 * log everything that printk could have logged. */
1479 avail
= audit_expand(ab
,
1480 max_t(unsigned, AUDIT_BUFSIZ
, 1+len
-avail
));
1483 len
= vsnprintf(skb_tail_pointer(skb
), avail
, fmt
, args2
);
1494 * audit_log_format - format a message into the audit buffer.
1496 * @fmt: format string
1497 * @...: optional parameters matching @fmt string
1499 * All the work is done in audit_log_vformat.
1501 void audit_log_format(struct audit_buffer
*ab
, const char *fmt
, ...)
1507 va_start(args
, fmt
);
1508 audit_log_vformat(ab
, fmt
, args
);
1513 * audit_log_hex - convert a buffer to hex and append it to the audit skb
1514 * @ab: the audit_buffer
1515 * @buf: buffer to convert to hex
1516 * @len: length of @buf to be converted
1518 * No return value; failure to expand is silently ignored.
1520 * This function will take the passed buf and convert it into a string of
1521 * ascii hex digits. The new string is placed onto the skb.
1523 void audit_log_n_hex(struct audit_buffer
*ab
, const unsigned char *buf
,
1526 int i
, avail
, new_len
;
1528 struct sk_buff
*skb
;
1535 avail
= skb_tailroom(skb
);
1537 if (new_len
>= avail
) {
1538 /* Round the buffer request up to the next multiple */
1539 new_len
= AUDIT_BUFSIZ
*(((new_len
-avail
)/AUDIT_BUFSIZ
) + 1);
1540 avail
= audit_expand(ab
, new_len
);
1545 ptr
= skb_tail_pointer(skb
);
1546 for (i
= 0; i
< len
; i
++)
1547 ptr
= hex_byte_pack_upper(ptr
, buf
[i
]);
1549 skb_put(skb
, len
<< 1); /* new string is twice the old string */
1553 * Format a string of no more than slen characters into the audit buffer,
1554 * enclosed in quote marks.
1556 void audit_log_n_string(struct audit_buffer
*ab
, const char *string
,
1561 struct sk_buff
*skb
;
1568 avail
= skb_tailroom(skb
);
1569 new_len
= slen
+ 3; /* enclosing quotes + null terminator */
1570 if (new_len
> avail
) {
1571 avail
= audit_expand(ab
, new_len
);
1575 ptr
= skb_tail_pointer(skb
);
1577 memcpy(ptr
, string
, slen
);
1581 skb_put(skb
, slen
+ 2); /* don't include null terminator */
1585 * audit_string_contains_control - does a string need to be logged in hex
1586 * @string: string to be checked
1587 * @len: max length of the string to check
1589 bool audit_string_contains_control(const char *string
, size_t len
)
1591 const unsigned char *p
;
1592 for (p
= string
; p
< (const unsigned char *)string
+ len
; p
++) {
1593 if (*p
== '"' || *p
< 0x21 || *p
> 0x7e)
1600 * audit_log_n_untrustedstring - log a string that may contain random characters
1602 * @len: length of string (not including trailing null)
1603 * @string: string to be logged
1605 * This code will escape a string that is passed to it if the string
1606 * contains a control character, unprintable character, double quote mark,
1607 * or a space. Unescaped strings will start and end with a double quote mark.
1608 * Strings that are escaped are printed in hex (2 digits per char).
1610 * The caller specifies the number of characters in the string to log, which may
1611 * or may not be the entire string.
1613 void audit_log_n_untrustedstring(struct audit_buffer
*ab
, const char *string
,
1616 if (audit_string_contains_control(string
, len
))
1617 audit_log_n_hex(ab
, string
, len
);
1619 audit_log_n_string(ab
, string
, len
);
1623 * audit_log_untrustedstring - log a string that may contain random characters
1625 * @string: string to be logged
1627 * Same as audit_log_n_untrustedstring(), except that strlen is used to
1628 * determine string length.
1630 void audit_log_untrustedstring(struct audit_buffer
*ab
, const char *string
)
1632 audit_log_n_untrustedstring(ab
, string
, strlen(string
));
1635 /* This is a helper-function to print the escaped d_path */
1636 void audit_log_d_path(struct audit_buffer
*ab
, const char *prefix
,
1637 const struct path
*path
)
1642 audit_log_format(ab
, "%s", prefix
);
1644 /* We will allow 11 spaces for ' (deleted)' to be appended */
1645 pathname
= kmalloc(PATH_MAX
+11, ab
->gfp_mask
);
1647 audit_log_string(ab
, "<no_memory>");
1650 p
= d_path(path
, pathname
, PATH_MAX
+11);
1651 if (IS_ERR(p
)) { /* Should never happen since we send PATH_MAX */
1652 /* FIXME: can we save some information here? */
1653 audit_log_string(ab
, "<too_long>");
1655 audit_log_untrustedstring(ab
, p
);
1659 void audit_log_session_info(struct audit_buffer
*ab
)
1661 unsigned int sessionid
= audit_get_sessionid(current
);
1662 uid_t auid
= from_kuid(&init_user_ns
, audit_get_loginuid(current
));
1664 audit_log_format(ab
, " auid=%u ses=%u", auid
, sessionid
);
1667 void audit_log_key(struct audit_buffer
*ab
, char *key
)
1669 audit_log_format(ab
, " key=");
1671 audit_log_untrustedstring(ab
, key
);
1673 audit_log_format(ab
, "(null)");
1676 void audit_log_cap(struct audit_buffer
*ab
, char *prefix
, kernel_cap_t
*cap
)
1680 audit_log_format(ab
, " %s=", prefix
);
1681 CAP_FOR_EACH_U32(i
) {
1682 audit_log_format(ab
, "%08x",
1683 cap
->cap
[CAP_LAST_U32
- i
]);
1687 static void audit_log_fcaps(struct audit_buffer
*ab
, struct audit_names
*name
)
1689 kernel_cap_t
*perm
= &name
->fcap
.permitted
;
1690 kernel_cap_t
*inh
= &name
->fcap
.inheritable
;
1693 if (!cap_isclear(*perm
)) {
1694 audit_log_cap(ab
, "cap_fp", perm
);
1697 if (!cap_isclear(*inh
)) {
1698 audit_log_cap(ab
, "cap_fi", inh
);
1703 audit_log_format(ab
, " cap_fe=%d cap_fver=%x",
1704 name
->fcap
.fE
, name
->fcap_ver
);
1707 static inline int audit_copy_fcaps(struct audit_names
*name
,
1708 const struct dentry
*dentry
)
1710 struct cpu_vfs_cap_data caps
;
1716 rc
= get_vfs_caps_from_disk(dentry
, &caps
);
1720 name
->fcap
.permitted
= caps
.permitted
;
1721 name
->fcap
.inheritable
= caps
.inheritable
;
1722 name
->fcap
.fE
= !!(caps
.magic_etc
& VFS_CAP_FLAGS_EFFECTIVE
);
1723 name
->fcap_ver
= (caps
.magic_etc
& VFS_CAP_REVISION_MASK
) >>
1724 VFS_CAP_REVISION_SHIFT
;
1729 /* Copy inode data into an audit_names. */
1730 void audit_copy_inode(struct audit_names
*name
, const struct dentry
*dentry
,
1731 const struct inode
*inode
)
1733 name
->ino
= inode
->i_ino
;
1734 name
->dev
= inode
->i_sb
->s_dev
;
1735 name
->mode
= inode
->i_mode
;
1736 name
->uid
= inode
->i_uid
;
1737 name
->gid
= inode
->i_gid
;
1738 name
->rdev
= inode
->i_rdev
;
1739 security_inode_getsecid(inode
, &name
->osid
);
1740 audit_copy_fcaps(name
, dentry
);
1744 * audit_log_name - produce AUDIT_PATH record from struct audit_names
1745 * @context: audit_context for the task
1746 * @n: audit_names structure with reportable details
1747 * @path: optional path to report instead of audit_names->name
1748 * @record_num: record number to report when handling a list of names
1749 * @call_panic: optional pointer to int that will be updated if secid fails
1751 void audit_log_name(struct audit_context
*context
, struct audit_names
*n
,
1752 struct path
*path
, int record_num
, int *call_panic
)
1754 struct audit_buffer
*ab
;
1755 ab
= audit_log_start(context
, GFP_KERNEL
, AUDIT_PATH
);
1759 audit_log_format(ab
, "item=%d", record_num
);
1762 audit_log_d_path(ab
, " name=", path
);
1764 switch (n
->name_len
) {
1765 case AUDIT_NAME_FULL
:
1766 /* log the full path */
1767 audit_log_format(ab
, " name=");
1768 audit_log_untrustedstring(ab
, n
->name
->name
);
1771 /* name was specified as a relative path and the
1772 * directory component is the cwd */
1773 audit_log_d_path(ab
, " name=", &context
->pwd
);
1776 /* log the name's directory component */
1777 audit_log_format(ab
, " name=");
1778 audit_log_n_untrustedstring(ab
, n
->name
->name
,
1782 audit_log_format(ab
, " name=(null)");
1784 if (n
->ino
!= AUDIT_INO_UNSET
)
1785 audit_log_format(ab
, " inode=%lu"
1786 " dev=%02x:%02x mode=%#ho"
1787 " ouid=%u ogid=%u rdev=%02x:%02x",
1792 from_kuid(&init_user_ns
, n
->uid
),
1793 from_kgid(&init_user_ns
, n
->gid
),
1799 if (security_secid_to_secctx(
1800 n
->osid
, &ctx
, &len
)) {
1801 audit_log_format(ab
, " osid=%u", n
->osid
);
1805 audit_log_format(ab
, " obj=%s", ctx
);
1806 security_release_secctx(ctx
, len
);
1810 /* log the audit_names record type */
1811 audit_log_format(ab
, " nametype=");
1813 case AUDIT_TYPE_NORMAL
:
1814 audit_log_format(ab
, "NORMAL");
1816 case AUDIT_TYPE_PARENT
:
1817 audit_log_format(ab
, "PARENT");
1819 case AUDIT_TYPE_CHILD_DELETE
:
1820 audit_log_format(ab
, "DELETE");
1822 case AUDIT_TYPE_CHILD_CREATE
:
1823 audit_log_format(ab
, "CREATE");
1826 audit_log_format(ab
, "UNKNOWN");
1830 audit_log_fcaps(ab
, n
);
1834 int audit_log_task_context(struct audit_buffer
*ab
)
1841 security_task_getsecid(current
, &sid
);
1845 error
= security_secid_to_secctx(sid
, &ctx
, &len
);
1847 if (error
!= -EINVAL
)
1852 audit_log_format(ab
, " subj=%s", ctx
);
1853 security_release_secctx(ctx
, len
);
1857 audit_panic("error in audit_log_task_context");
1860 EXPORT_SYMBOL(audit_log_task_context
);
1862 void audit_log_d_path_exe(struct audit_buffer
*ab
,
1863 struct mm_struct
*mm
)
1865 struct file
*exe_file
;
1870 exe_file
= get_mm_exe_file(mm
);
1874 audit_log_d_path(ab
, " exe=", &exe_file
->f_path
);
1878 audit_log_format(ab
, " exe=(null)");
1881 void audit_log_task_info(struct audit_buffer
*ab
, struct task_struct
*tsk
)
1883 const struct cred
*cred
;
1884 char comm
[sizeof(tsk
->comm
)];
1890 /* tsk == current */
1891 cred
= current_cred();
1893 spin_lock_irq(&tsk
->sighand
->siglock
);
1894 if (tsk
->signal
&& tsk
->signal
->tty
&& tsk
->signal
->tty
->name
)
1895 tty
= tsk
->signal
->tty
->name
;
1898 spin_unlock_irq(&tsk
->sighand
->siglock
);
1900 audit_log_format(ab
,
1901 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1902 " euid=%u suid=%u fsuid=%u"
1903 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1906 from_kuid(&init_user_ns
, audit_get_loginuid(tsk
)),
1907 from_kuid(&init_user_ns
, cred
->uid
),
1908 from_kgid(&init_user_ns
, cred
->gid
),
1909 from_kuid(&init_user_ns
, cred
->euid
),
1910 from_kuid(&init_user_ns
, cred
->suid
),
1911 from_kuid(&init_user_ns
, cred
->fsuid
),
1912 from_kgid(&init_user_ns
, cred
->egid
),
1913 from_kgid(&init_user_ns
, cred
->sgid
),
1914 from_kgid(&init_user_ns
, cred
->fsgid
),
1915 tty
, audit_get_sessionid(tsk
));
1917 audit_log_format(ab
, " comm=");
1918 audit_log_untrustedstring(ab
, get_task_comm(comm
, tsk
));
1920 audit_log_d_path_exe(ab
, tsk
->mm
);
1921 audit_log_task_context(ab
);
1923 EXPORT_SYMBOL(audit_log_task_info
);
1926 * audit_log_link_denied - report a link restriction denial
1927 * @operation: specific link operation
1928 * @link: the path that triggered the restriction
1930 void audit_log_link_denied(const char *operation
, struct path
*link
)
1932 struct audit_buffer
*ab
;
1933 struct audit_names
*name
;
1935 name
= kzalloc(sizeof(*name
), GFP_NOFS
);
1939 /* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */
1940 ab
= audit_log_start(current
->audit_context
, GFP_KERNEL
,
1944 audit_log_format(ab
, "op=%s", operation
);
1945 audit_log_task_info(ab
, current
);
1946 audit_log_format(ab
, " res=0");
1949 /* Generate AUDIT_PATH record with object. */
1950 name
->type
= AUDIT_TYPE_NORMAL
;
1951 audit_copy_inode(name
, link
->dentry
, d_backing_inode(link
->dentry
));
1952 audit_log_name(current
->audit_context
, name
, link
, 0, NULL
);
1958 * audit_log_end - end one audit record
1959 * @ab: the audit_buffer
1961 * netlink_unicast() cannot be called inside an irq context because it blocks
1962 * (last arg, flags, is not set to MSG_DONTWAIT), so the audit buffer is placed
1963 * on a queue and a tasklet is scheduled to remove them from the queue outside
1964 * the irq context. May be called in any context.
1966 void audit_log_end(struct audit_buffer
*ab
)
1970 if (!audit_rate_check()) {
1971 audit_log_lost("rate limit exceeded");
1973 struct nlmsghdr
*nlh
= nlmsg_hdr(ab
->skb
);
1975 nlh
->nlmsg_len
= ab
->skb
->len
;
1976 kauditd_send_multicast_skb(ab
->skb
, ab
->gfp_mask
);
1979 * The original kaudit unicast socket sends up messages with
1980 * nlmsg_len set to the payload length rather than the entire
1981 * message length. This breaks the standard set by netlink.
1982 * The existing auditd daemon assumes this breakage. Fixing
1983 * this would require co-ordinating a change in the established
1984 * protocol between the kaudit kernel subsystem and the auditd
1987 nlh
->nlmsg_len
-= NLMSG_HDRLEN
;
1990 skb_queue_tail(&audit_skb_queue
, ab
->skb
);
1991 wake_up_interruptible(&kauditd_wait
);
1993 audit_printk_skb(ab
->skb
);
1997 audit_buffer_free(ab
);
2001 * audit_log - Log an audit record
2002 * @ctx: audit context
2003 * @gfp_mask: type of allocation
2004 * @type: audit message type
2005 * @fmt: format string to use
2006 * @...: variable parameters matching the format string
2008 * This is a convenience function that calls audit_log_start,
2009 * audit_log_vformat, and audit_log_end. It may be called
2012 void audit_log(struct audit_context
*ctx
, gfp_t gfp_mask
, int type
,
2013 const char *fmt
, ...)
2015 struct audit_buffer
*ab
;
2018 ab
= audit_log_start(ctx
, gfp_mask
, type
);
2020 va_start(args
, fmt
);
2021 audit_log_vformat(ab
, fmt
, args
);
2027 #ifdef CONFIG_SECURITY
2029 * audit_log_secctx - Converts and logs SELinux context
2031 * @secid: security number
2033 * This is a helper function that calls security_secid_to_secctx to convert
2034 * secid to secctx and then adds the (converted) SELinux context to the audit
2035 * log by calling audit_log_format, thus also preventing leak of internal secid
2036 * to userspace. If secid cannot be converted audit_panic is called.
2038 void audit_log_secctx(struct audit_buffer
*ab
, u32 secid
)
2043 if (security_secid_to_secctx(secid
, &secctx
, &len
)) {
2044 audit_panic("Cannot convert secid to context");
2046 audit_log_format(ab
, " obj=%s", secctx
);
2047 security_release_secctx(secctx
, len
);
2050 EXPORT_SYMBOL(audit_log_secctx
);
2053 EXPORT_SYMBOL(audit_log_start
);
2054 EXPORT_SYMBOL(audit_log_end
);
2055 EXPORT_SYMBOL(audit_log_format
);
2056 EXPORT_SYMBOL(audit_log
);