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/init.h>
47 #include <linux/types.h>
48 #include <linux/atomic.h>
50 #include <linux/export.h>
51 #include <linux/slab.h>
52 #include <linux/err.h>
53 #include <linux/kthread.h>
54 #include <linux/kernel.h>
55 #include <linux/syscalls.h>
57 #include <linux/audit.h>
60 #include <net/netlink.h>
61 #include <linux/skbuff.h>
62 #ifdef CONFIG_SECURITY
63 #include <linux/security.h>
65 #include <linux/freezer.h>
66 #include <linux/tty.h>
67 #include <linux/pid_namespace.h>
68 #include <net/netns/generic.h>
72 /* No auditing will take place until audit_initialized == AUDIT_INITIALIZED.
73 * (Initialization happens after skb_init is called.) */
74 #define AUDIT_DISABLED -1
75 #define AUDIT_UNINITIALIZED 0
76 #define AUDIT_INITIALIZED 1
77 static int audit_initialized
;
81 #define AUDIT_LOCKED 2
83 u32 audit_ever_enabled
;
85 EXPORT_SYMBOL_GPL(audit_enabled
);
87 /* Default state when kernel boots without any parameters. */
88 static u32 audit_default
;
90 /* If auditing cannot proceed, audit_failure selects what happens. */
91 static u32 audit_failure
= AUDIT_FAIL_PRINTK
;
94 * If audit records are to be written to the netlink socket, audit_pid
95 * contains the pid of the auditd process and audit_nlk_portid contains
96 * the portid to use to send netlink messages to that process.
99 static __u32 audit_nlk_portid
;
101 /* If audit_rate_limit is non-zero, limit the rate of sending audit records
102 * to that number per second. This prevents DoS attacks, but results in
103 * audit records being dropped. */
104 static u32 audit_rate_limit
;
106 /* Number of outstanding audit_buffers allowed.
107 * When set to zero, this means unlimited. */
108 static u32 audit_backlog_limit
= 64;
109 #define AUDIT_BACKLOG_WAIT_TIME (60 * HZ)
110 static u32 audit_backlog_wait_time_master
= AUDIT_BACKLOG_WAIT_TIME
;
111 static u32 audit_backlog_wait_time
= AUDIT_BACKLOG_WAIT_TIME
;
112 static u32 audit_backlog_wait_overflow
= 0;
114 /* The identity of the user shutting down the audit system. */
115 kuid_t audit_sig_uid
= INVALID_UID
;
116 pid_t audit_sig_pid
= -1;
117 u32 audit_sig_sid
= 0;
119 /* Records can be lost in several ways:
120 0) [suppressed in audit_alloc]
121 1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
122 2) out of memory in audit_log_move [alloc_skb]
123 3) suppressed due to audit_rate_limit
124 4) suppressed due to audit_backlog_limit
126 static atomic_t audit_lost
= ATOMIC_INIT(0);
128 /* The netlink socket. */
129 static struct sock
*audit_sock
;
130 static int audit_net_id
;
132 /* Hash for inode-based rules */
133 struct list_head audit_inode_hash
[AUDIT_INODE_BUCKETS
];
135 /* The audit_freelist is a list of pre-allocated audit buffers (if more
136 * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
137 * being placed on the freelist). */
138 static DEFINE_SPINLOCK(audit_freelist_lock
);
139 static int audit_freelist_count
;
140 static LIST_HEAD(audit_freelist
);
142 static struct sk_buff_head audit_skb_queue
;
143 /* queue of skbs to send to auditd when/if it comes back */
144 static struct sk_buff_head audit_skb_hold_queue
;
145 static struct task_struct
*kauditd_task
;
146 static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait
);
147 static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait
);
149 static struct audit_features af
= {.vers
= AUDIT_FEATURE_VERSION
,
154 static char *audit_feature_names
[2] = {
155 "only_unset_loginuid",
156 "loginuid_immutable",
160 /* Serialize requests from userspace. */
161 DEFINE_MUTEX(audit_cmd_mutex
);
163 /* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
164 * audit records. Since printk uses a 1024 byte buffer, this buffer
165 * should be at least that large. */
166 #define AUDIT_BUFSIZ 1024
168 /* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the
169 * audit_freelist. Doing so eliminates many kmalloc/kfree calls. */
170 #define AUDIT_MAXFREE (2*NR_CPUS)
172 /* The audit_buffer is used when formatting an audit record. The caller
173 * locks briefly to get the record off the freelist or to allocate the
174 * buffer, and locks briefly to send the buffer to the netlink layer or
175 * to place it on a transmit queue. Multiple audit_buffers can be in
176 * use simultaneously. */
177 struct audit_buffer
{
178 struct list_head list
;
179 struct sk_buff
*skb
; /* formatted skb ready to send */
180 struct audit_context
*ctx
; /* NULL or associated context */
190 static void audit_set_portid(struct audit_buffer
*ab
, __u32 portid
)
193 struct nlmsghdr
*nlh
= nlmsg_hdr(ab
->skb
);
194 nlh
->nlmsg_pid
= portid
;
198 void audit_panic(const char *message
)
200 switch (audit_failure
) {
201 case AUDIT_FAIL_SILENT
:
203 case AUDIT_FAIL_PRINTK
:
204 if (printk_ratelimit())
205 pr_err("%s\n", message
);
207 case AUDIT_FAIL_PANIC
:
208 /* test audit_pid since printk is always losey, why bother? */
210 panic("audit: %s\n", message
);
215 static inline int audit_rate_check(void)
217 static unsigned long last_check
= 0;
218 static int messages
= 0;
219 static DEFINE_SPINLOCK(lock
);
222 unsigned long elapsed
;
225 if (!audit_rate_limit
) return 1;
227 spin_lock_irqsave(&lock
, flags
);
228 if (++messages
< audit_rate_limit
) {
232 elapsed
= now
- last_check
;
239 spin_unlock_irqrestore(&lock
, flags
);
245 * audit_log_lost - conditionally log lost audit message event
246 * @message: the message stating reason for lost audit message
248 * Emit at least 1 message per second, even if audit_rate_check is
250 * Always increment the lost messages counter.
252 void audit_log_lost(const char *message
)
254 static unsigned long last_msg
= 0;
255 static DEFINE_SPINLOCK(lock
);
260 atomic_inc(&audit_lost
);
262 print
= (audit_failure
== AUDIT_FAIL_PANIC
|| !audit_rate_limit
);
265 spin_lock_irqsave(&lock
, flags
);
267 if (now
- last_msg
> HZ
) {
271 spin_unlock_irqrestore(&lock
, flags
);
275 if (printk_ratelimit())
276 pr_warn("audit_lost=%u audit_rate_limit=%u audit_backlog_limit=%u\n",
277 atomic_read(&audit_lost
),
279 audit_backlog_limit
);
280 audit_panic(message
);
284 static int audit_log_config_change(char *function_name
, u32
new, u32 old
,
287 struct audit_buffer
*ab
;
290 ab
= audit_log_start(NULL
, GFP_KERNEL
, AUDIT_CONFIG_CHANGE
);
293 audit_log_format(ab
, "%s=%u old=%u", function_name
, new, old
);
294 audit_log_session_info(ab
);
295 rc
= audit_log_task_context(ab
);
297 allow_changes
= 0; /* Something weird, deny request */
298 audit_log_format(ab
, " res=%d", allow_changes
);
303 static int audit_do_config_change(char *function_name
, u32
*to_change
, u32
new)
305 int allow_changes
, rc
= 0;
306 u32 old
= *to_change
;
308 /* check if we are locked */
309 if (audit_enabled
== AUDIT_LOCKED
)
314 if (audit_enabled
!= AUDIT_OFF
) {
315 rc
= audit_log_config_change(function_name
, new, old
, allow_changes
);
320 /* If we are allowed, make the change */
321 if (allow_changes
== 1)
323 /* Not allowed, update reason */
329 static int audit_set_rate_limit(u32 limit
)
331 return audit_do_config_change("audit_rate_limit", &audit_rate_limit
, limit
);
334 static int audit_set_backlog_limit(u32 limit
)
336 return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit
, limit
);
339 static int audit_set_backlog_wait_time(u32 timeout
)
341 return audit_do_config_change("audit_backlog_wait_time",
342 &audit_backlog_wait_time_master
, timeout
);
345 static int audit_set_enabled(u32 state
)
348 if (state
< AUDIT_OFF
|| state
> AUDIT_LOCKED
)
351 rc
= audit_do_config_change("audit_enabled", &audit_enabled
, state
);
353 audit_ever_enabled
|= !!state
;
358 static int audit_set_failure(u32 state
)
360 if (state
!= AUDIT_FAIL_SILENT
361 && state
!= AUDIT_FAIL_PRINTK
362 && state
!= AUDIT_FAIL_PANIC
)
365 return audit_do_config_change("audit_failure", &audit_failure
, state
);
369 * Queue skbs to be sent to auditd when/if it comes back. These skbs should
370 * already have been sent via prink/syslog and so if these messages are dropped
371 * it is not a huge concern since we already passed the audit_log_lost()
372 * notification and stuff. This is just nice to get audit messages during
373 * boot before auditd is running or messages generated while auditd is stopped.
374 * This only holds messages is audit_default is set, aka booting with audit=1
375 * or building your kernel that way.
377 static void audit_hold_skb(struct sk_buff
*skb
)
380 (!audit_backlog_limit
||
381 skb_queue_len(&audit_skb_hold_queue
) < audit_backlog_limit
))
382 skb_queue_tail(&audit_skb_hold_queue
, skb
);
388 * For one reason or another this nlh isn't getting delivered to the userspace
389 * audit daemon, just send it to printk.
391 static void audit_printk_skb(struct sk_buff
*skb
)
393 struct nlmsghdr
*nlh
= nlmsg_hdr(skb
);
394 char *data
= nlmsg_data(nlh
);
396 if (nlh
->nlmsg_type
!= AUDIT_EOE
) {
397 if (printk_ratelimit())
398 pr_notice("type=%d %s\n", nlh
->nlmsg_type
, data
);
400 audit_log_lost("printk limit exceeded");
406 static void kauditd_send_skb(struct sk_buff
*skb
)
409 /* take a reference in case we can't send it and we want to hold it */
411 err
= netlink_unicast(audit_sock
, skb
, audit_nlk_portid
, 0);
413 BUG_ON(err
!= -ECONNREFUSED
); /* Shouldn't happen */
415 pr_err("*NO* daemon at audit_pid=%d\n", audit_pid
);
416 audit_log_lost("auditd disappeared");
420 /* we might get lucky and get this in the next auditd */
423 /* drop the extra reference if sent ok */
428 * kauditd_send_multicast_skb - send the skb to multicast userspace listeners
430 * This function doesn't consume an skb as might be expected since it has to
433 static void kauditd_send_multicast_skb(struct sk_buff
*skb
, gfp_t gfp_mask
)
435 struct sk_buff
*copy
;
436 struct audit_net
*aunet
= net_generic(&init_net
, audit_net_id
);
437 struct sock
*sock
= aunet
->nlsk
;
439 if (!netlink_has_listeners(sock
, AUDIT_NLGRP_READLOG
))
443 * The seemingly wasteful skb_copy() rather than bumping the refcount
444 * using skb_get() is necessary because non-standard mods are made to
445 * the skb by the original kaudit unicast socket send routine. The
446 * existing auditd daemon assumes this breakage. Fixing this would
447 * require co-ordinating a change in the established protocol between
448 * the kaudit kernel subsystem and the auditd userspace code. There is
449 * no reason for new multicast clients to continue with this
452 copy
= skb_copy(skb
, gfp_mask
);
456 nlmsg_multicast(sock
, copy
, 0, AUDIT_NLGRP_READLOG
, gfp_mask
);
460 * flush_hold_queue - empty the hold queue if auditd appears
462 * If auditd just started, drain the queue of messages already
463 * sent to syslog/printk. Remember loss here is ok. We already
464 * called audit_log_lost() if it didn't go out normally. so the
465 * race between the skb_dequeue and the next check for audit_pid
468 * If you ever find kauditd to be too slow we can get a perf win
469 * by doing our own locking and keeping better track if there
470 * are messages in this queue. I don't see the need now, but
471 * in 5 years when I want to play with this again I'll see this
472 * note and still have no friggin idea what i'm thinking today.
474 static void flush_hold_queue(void)
478 if (!audit_default
|| !audit_pid
)
481 skb
= skb_dequeue(&audit_skb_hold_queue
);
485 while (skb
&& audit_pid
) {
486 kauditd_send_skb(skb
);
487 skb
= skb_dequeue(&audit_skb_hold_queue
);
491 * if auditd just disappeared but we
492 * dequeued an skb we need to drop ref
498 static int kauditd_thread(void *dummy
)
501 while (!kthread_should_stop()) {
503 DECLARE_WAITQUEUE(wait
, current
);
507 skb
= skb_dequeue(&audit_skb_queue
);
510 if (skb_queue_len(&audit_skb_queue
) <= audit_backlog_limit
)
511 wake_up(&audit_backlog_wait
);
513 kauditd_send_skb(skb
);
515 audit_printk_skb(skb
);
518 set_current_state(TASK_INTERRUPTIBLE
);
519 add_wait_queue(&kauditd_wait
, &wait
);
521 if (!skb_queue_len(&audit_skb_queue
)) {
526 __set_current_state(TASK_RUNNING
);
527 remove_wait_queue(&kauditd_wait
, &wait
);
532 int audit_send_list(void *_dest
)
534 struct audit_netlink_list
*dest
= _dest
;
536 struct net
*net
= dest
->net
;
537 struct audit_net
*aunet
= net_generic(net
, audit_net_id
);
539 /* wait for parent to finish and send an ACK */
540 mutex_lock(&audit_cmd_mutex
);
541 mutex_unlock(&audit_cmd_mutex
);
543 while ((skb
= __skb_dequeue(&dest
->q
)) != NULL
)
544 netlink_unicast(aunet
->nlsk
, skb
, dest
->portid
, 0);
552 struct sk_buff
*audit_make_reply(__u32 portid
, int seq
, int type
, int done
,
553 int multi
, const void *payload
, int size
)
556 struct nlmsghdr
*nlh
;
558 int flags
= multi
? NLM_F_MULTI
: 0;
559 int t
= done
? NLMSG_DONE
: type
;
561 skb
= nlmsg_new(size
, GFP_KERNEL
);
565 nlh
= nlmsg_put(skb
, portid
, seq
, t
, size
, flags
);
568 data
= nlmsg_data(nlh
);
569 memcpy(data
, payload
, size
);
577 static int audit_send_reply_thread(void *arg
)
579 struct audit_reply
*reply
= (struct audit_reply
*)arg
;
580 struct net
*net
= reply
->net
;
581 struct audit_net
*aunet
= net_generic(net
, audit_net_id
);
583 mutex_lock(&audit_cmd_mutex
);
584 mutex_unlock(&audit_cmd_mutex
);
586 /* Ignore failure. It'll only happen if the sender goes away,
587 because our timeout is set to infinite. */
588 netlink_unicast(aunet
->nlsk
, reply
->skb
, reply
->portid
, 0);
594 * audit_send_reply - send an audit reply message via netlink
595 * @request_skb: skb of request we are replying to (used to target the reply)
596 * @seq: sequence number
597 * @type: audit message type
598 * @done: done (last) flag
599 * @multi: multi-part message flag
600 * @payload: payload data
601 * @size: payload size
603 * Allocates an skb, builds the netlink message, and sends it to the port id.
604 * No failure notifications.
606 static void audit_send_reply(struct sk_buff
*request_skb
, int seq
, int type
, int done
,
607 int multi
, const void *payload
, int size
)
609 u32 portid
= NETLINK_CB(request_skb
).portid
;
610 struct net
*net
= sock_net(NETLINK_CB(request_skb
).sk
);
612 struct task_struct
*tsk
;
613 struct audit_reply
*reply
= kmalloc(sizeof(struct audit_reply
),
619 skb
= audit_make_reply(portid
, seq
, type
, done
, multi
, payload
, size
);
623 reply
->net
= get_net(net
);
624 reply
->portid
= portid
;
627 tsk
= kthread_run(audit_send_reply_thread
, reply
, "audit_send_reply");
636 * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
639 static int audit_netlink_ok(struct sk_buff
*skb
, u16 msg_type
)
643 /* Only support initial user namespace for now. */
645 * We return ECONNREFUSED because it tricks userspace into thinking
646 * that audit was not configured into the kernel. Lots of users
647 * configure their PAM stack (because that's what the distro does)
648 * to reject login if unable to send messages to audit. If we return
649 * ECONNREFUSED the PAM stack thinks the kernel does not have audit
650 * configured in and will let login proceed. If we return EPERM
651 * userspace will reject all logins. This should be removed when we
652 * support non init namespaces!!
654 if (current_user_ns() != &init_user_ns
)
655 return -ECONNREFUSED
;
664 case AUDIT_GET_FEATURE
:
665 case AUDIT_SET_FEATURE
:
666 case AUDIT_LIST_RULES
:
669 case AUDIT_SIGNAL_INFO
:
673 case AUDIT_MAKE_EQUIV
:
674 /* Only support auditd and auditctl in initial pid namespace
676 if (task_active_pid_ns(current
) != &init_pid_ns
)
679 if (!netlink_capable(skb
, CAP_AUDIT_CONTROL
))
683 case AUDIT_FIRST_USER_MSG
... AUDIT_LAST_USER_MSG
:
684 case AUDIT_FIRST_USER_MSG2
... AUDIT_LAST_USER_MSG2
:
685 if (!netlink_capable(skb
, CAP_AUDIT_WRITE
))
688 default: /* bad msg */
695 static int audit_log_common_recv_msg(struct audit_buffer
**ab
, u16 msg_type
)
698 uid_t uid
= from_kuid(&init_user_ns
, current_uid());
699 pid_t pid
= task_tgid_nr(current
);
701 if (!audit_enabled
&& msg_type
!= AUDIT_USER_AVC
) {
706 *ab
= audit_log_start(NULL
, GFP_KERNEL
, msg_type
);
709 audit_log_format(*ab
, "pid=%d uid=%u", pid
, uid
);
710 audit_log_session_info(*ab
);
711 audit_log_task_context(*ab
);
716 int is_audit_feature_set(int i
)
718 return af
.features
& AUDIT_FEATURE_TO_MASK(i
);
722 static int audit_get_feature(struct sk_buff
*skb
)
726 seq
= nlmsg_hdr(skb
)->nlmsg_seq
;
728 audit_send_reply(skb
, seq
, AUDIT_GET_FEATURE
, 0, 0, &af
, sizeof(af
));
733 static void audit_log_feature_change(int which
, u32 old_feature
, u32 new_feature
,
734 u32 old_lock
, u32 new_lock
, int res
)
736 struct audit_buffer
*ab
;
738 if (audit_enabled
== AUDIT_OFF
)
741 ab
= audit_log_start(NULL
, GFP_KERNEL
, AUDIT_FEATURE_CHANGE
);
742 audit_log_task_info(ab
, current
);
743 audit_log_format(ab
, " feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d",
744 audit_feature_names
[which
], !!old_feature
, !!new_feature
,
745 !!old_lock
, !!new_lock
, res
);
749 static int audit_set_feature(struct sk_buff
*skb
)
751 struct audit_features
*uaf
;
754 BUILD_BUG_ON(AUDIT_LAST_FEATURE
+ 1 > ARRAY_SIZE(audit_feature_names
));
755 uaf
= nlmsg_data(nlmsg_hdr(skb
));
757 /* if there is ever a version 2 we should handle that here */
759 for (i
= 0; i
<= AUDIT_LAST_FEATURE
; i
++) {
760 u32 feature
= AUDIT_FEATURE_TO_MASK(i
);
761 u32 old_feature
, new_feature
, old_lock
, new_lock
;
763 /* if we are not changing this feature, move along */
764 if (!(feature
& uaf
->mask
))
767 old_feature
= af
.features
& feature
;
768 new_feature
= uaf
->features
& feature
;
769 new_lock
= (uaf
->lock
| af
.lock
) & feature
;
770 old_lock
= af
.lock
& feature
;
772 /* are we changing a locked feature? */
773 if (old_lock
&& (new_feature
!= old_feature
)) {
774 audit_log_feature_change(i
, old_feature
, new_feature
,
775 old_lock
, new_lock
, 0);
779 /* nothing invalid, do the changes */
780 for (i
= 0; i
<= AUDIT_LAST_FEATURE
; i
++) {
781 u32 feature
= AUDIT_FEATURE_TO_MASK(i
);
782 u32 old_feature
, new_feature
, old_lock
, new_lock
;
784 /* if we are not changing this feature, move along */
785 if (!(feature
& uaf
->mask
))
788 old_feature
= af
.features
& feature
;
789 new_feature
= uaf
->features
& feature
;
790 old_lock
= af
.lock
& feature
;
791 new_lock
= (uaf
->lock
| af
.lock
) & feature
;
793 if (new_feature
!= old_feature
)
794 audit_log_feature_change(i
, old_feature
, new_feature
,
795 old_lock
, new_lock
, 1);
798 af
.features
|= feature
;
800 af
.features
&= ~feature
;
807 static int audit_receive_msg(struct sk_buff
*skb
, struct nlmsghdr
*nlh
)
812 struct audit_buffer
*ab
;
813 u16 msg_type
= nlh
->nlmsg_type
;
814 struct audit_sig_info
*sig_data
;
818 err
= audit_netlink_ok(skb
, msg_type
);
822 /* As soon as there's any sign of userspace auditd,
823 * start kauditd to talk to it */
825 kauditd_task
= kthread_run(kauditd_thread
, NULL
, "kauditd");
826 if (IS_ERR(kauditd_task
)) {
827 err
= PTR_ERR(kauditd_task
);
832 seq
= nlh
->nlmsg_seq
;
833 data
= nlmsg_data(nlh
);
837 struct audit_status s
;
838 memset(&s
, 0, sizeof(s
));
839 s
.enabled
= audit_enabled
;
840 s
.failure
= audit_failure
;
842 s
.rate_limit
= audit_rate_limit
;
843 s
.backlog_limit
= audit_backlog_limit
;
844 s
.lost
= atomic_read(&audit_lost
);
845 s
.backlog
= skb_queue_len(&audit_skb_queue
);
846 s
.feature_bitmap
= AUDIT_FEATURE_BITMAP_ALL
;
847 s
.backlog_wait_time
= audit_backlog_wait_time_master
;
848 audit_send_reply(skb
, seq
, AUDIT_GET
, 0, 0, &s
, sizeof(s
));
852 struct audit_status s
;
853 memset(&s
, 0, sizeof(s
));
854 /* guard against past and future API changes */
855 memcpy(&s
, data
, min_t(size_t, sizeof(s
), nlmsg_len(nlh
)));
856 if (s
.mask
& AUDIT_STATUS_ENABLED
) {
857 err
= audit_set_enabled(s
.enabled
);
861 if (s
.mask
& AUDIT_STATUS_FAILURE
) {
862 err
= audit_set_failure(s
.failure
);
866 if (s
.mask
& AUDIT_STATUS_PID
) {
869 if ((!new_pid
) && (task_tgid_vnr(current
) != audit_pid
))
871 if (audit_enabled
!= AUDIT_OFF
)
872 audit_log_config_change("audit_pid", new_pid
, audit_pid
, 1);
874 audit_nlk_portid
= NETLINK_CB(skb
).portid
;
875 audit_sock
= skb
->sk
;
877 if (s
.mask
& AUDIT_STATUS_RATE_LIMIT
) {
878 err
= audit_set_rate_limit(s
.rate_limit
);
882 if (s
.mask
& AUDIT_STATUS_BACKLOG_LIMIT
) {
883 err
= audit_set_backlog_limit(s
.backlog_limit
);
887 if (s
.mask
& AUDIT_STATUS_BACKLOG_WAIT_TIME
) {
888 if (sizeof(s
) > (size_t)nlh
->nlmsg_len
)
890 if (s
.backlog_wait_time
< 0 ||
891 s
.backlog_wait_time
> 10*AUDIT_BACKLOG_WAIT_TIME
)
893 err
= audit_set_backlog_wait_time(s
.backlog_wait_time
);
899 case AUDIT_GET_FEATURE
:
900 err
= audit_get_feature(skb
);
904 case AUDIT_SET_FEATURE
:
905 err
= audit_set_feature(skb
);
910 case AUDIT_FIRST_USER_MSG
... AUDIT_LAST_USER_MSG
:
911 case AUDIT_FIRST_USER_MSG2
... AUDIT_LAST_USER_MSG2
:
912 if (!audit_enabled
&& msg_type
!= AUDIT_USER_AVC
)
915 err
= audit_filter_user(msg_type
);
916 if (err
== 1) { /* match or error */
918 if (msg_type
== AUDIT_USER_TTY
) {
919 err
= tty_audit_push_current();
923 mutex_unlock(&audit_cmd_mutex
);
924 audit_log_common_recv_msg(&ab
, msg_type
);
925 if (msg_type
!= AUDIT_USER_TTY
)
926 audit_log_format(ab
, " msg='%.*s'",
927 AUDIT_MESSAGE_TEXT_MAX
,
932 audit_log_format(ab
, " data=");
933 size
= nlmsg_len(nlh
);
935 ((unsigned char *)data
)[size
- 1] == '\0')
937 audit_log_n_untrustedstring(ab
, data
, size
);
939 audit_set_portid(ab
, NETLINK_CB(skb
).portid
);
941 mutex_lock(&audit_cmd_mutex
);
946 if (nlmsg_len(nlh
) < sizeof(struct audit_rule_data
))
948 if (audit_enabled
== AUDIT_LOCKED
) {
949 audit_log_common_recv_msg(&ab
, AUDIT_CONFIG_CHANGE
);
950 audit_log_format(ab
, " audit_enabled=%d res=0", audit_enabled
);
954 err
= audit_rule_change(msg_type
, NETLINK_CB(skb
).portid
,
955 seq
, data
, nlmsg_len(nlh
));
957 case AUDIT_LIST_RULES
:
958 err
= audit_list_rules_send(skb
, seq
);
962 audit_log_common_recv_msg(&ab
, AUDIT_CONFIG_CHANGE
);
963 audit_log_format(ab
, " op=trim res=1");
966 case AUDIT_MAKE_EQUIV
: {
969 size_t msglen
= nlmsg_len(nlh
);
973 if (msglen
< 2 * sizeof(u32
))
975 memcpy(sizes
, bufp
, 2 * sizeof(u32
));
976 bufp
+= 2 * sizeof(u32
);
977 msglen
-= 2 * sizeof(u32
);
978 old
= audit_unpack_string(&bufp
, &msglen
, sizes
[0]);
983 new = audit_unpack_string(&bufp
, &msglen
, sizes
[1]);
989 /* OK, here comes... */
990 err
= audit_tag_tree(old
, new);
992 audit_log_common_recv_msg(&ab
, AUDIT_CONFIG_CHANGE
);
994 audit_log_format(ab
, " op=make_equiv old=");
995 audit_log_untrustedstring(ab
, old
);
996 audit_log_format(ab
, " new=");
997 audit_log_untrustedstring(ab
, new);
998 audit_log_format(ab
, " res=%d", !err
);
1004 case AUDIT_SIGNAL_INFO
:
1006 if (audit_sig_sid
) {
1007 err
= security_secid_to_secctx(audit_sig_sid
, &ctx
, &len
);
1011 sig_data
= kmalloc(sizeof(*sig_data
) + len
, GFP_KERNEL
);
1014 security_release_secctx(ctx
, len
);
1017 sig_data
->uid
= from_kuid(&init_user_ns
, audit_sig_uid
);
1018 sig_data
->pid
= audit_sig_pid
;
1019 if (audit_sig_sid
) {
1020 memcpy(sig_data
->ctx
, ctx
, len
);
1021 security_release_secctx(ctx
, len
);
1023 audit_send_reply(skb
, seq
, AUDIT_SIGNAL_INFO
, 0, 0,
1024 sig_data
, sizeof(*sig_data
) + len
);
1027 case AUDIT_TTY_GET
: {
1028 struct audit_tty_status s
;
1029 struct task_struct
*tsk
= current
;
1031 spin_lock(&tsk
->sighand
->siglock
);
1032 s
.enabled
= tsk
->signal
->audit_tty
;
1033 s
.log_passwd
= tsk
->signal
->audit_tty_log_passwd
;
1034 spin_unlock(&tsk
->sighand
->siglock
);
1036 audit_send_reply(skb
, seq
, AUDIT_TTY_GET
, 0, 0, &s
, sizeof(s
));
1039 case AUDIT_TTY_SET
: {
1040 struct audit_tty_status s
, old
;
1041 struct task_struct
*tsk
= current
;
1042 struct audit_buffer
*ab
;
1044 memset(&s
, 0, sizeof(s
));
1045 /* guard against past and future API changes */
1046 memcpy(&s
, data
, min_t(size_t, sizeof(s
), nlmsg_len(nlh
)));
1047 /* check if new data is valid */
1048 if ((s
.enabled
!= 0 && s
.enabled
!= 1) ||
1049 (s
.log_passwd
!= 0 && s
.log_passwd
!= 1))
1052 spin_lock(&tsk
->sighand
->siglock
);
1053 old
.enabled
= tsk
->signal
->audit_tty
;
1054 old
.log_passwd
= tsk
->signal
->audit_tty_log_passwd
;
1056 tsk
->signal
->audit_tty
= s
.enabled
;
1057 tsk
->signal
->audit_tty_log_passwd
= s
.log_passwd
;
1059 spin_unlock(&tsk
->sighand
->siglock
);
1061 audit_log_common_recv_msg(&ab
, AUDIT_CONFIG_CHANGE
);
1062 audit_log_format(ab
, " op=tty_set old-enabled=%d new-enabled=%d"
1063 " old-log_passwd=%d new-log_passwd=%d res=%d",
1064 old
.enabled
, s
.enabled
, old
.log_passwd
,
1065 s
.log_passwd
, !err
);
1074 return err
< 0 ? err
: 0;
1078 * Get message from skb. Each message is processed by audit_receive_msg.
1079 * Malformed skbs with wrong length are discarded silently.
1081 static void audit_receive_skb(struct sk_buff
*skb
)
1083 struct nlmsghdr
*nlh
;
1085 * len MUST be signed for nlmsg_next to be able to dec it below 0
1086 * if the nlmsg_len was not aligned
1091 nlh
= nlmsg_hdr(skb
);
1094 while (nlmsg_ok(nlh
, len
)) {
1095 err
= audit_receive_msg(skb
, nlh
);
1096 /* if err or if this message says it wants a response */
1097 if (err
|| (nlh
->nlmsg_flags
& NLM_F_ACK
))
1098 netlink_ack(skb
, nlh
, err
);
1100 nlh
= nlmsg_next(nlh
, &len
);
1104 /* Receive messages from netlink socket. */
1105 static void audit_receive(struct sk_buff
*skb
)
1107 mutex_lock(&audit_cmd_mutex
);
1108 audit_receive_skb(skb
);
1109 mutex_unlock(&audit_cmd_mutex
);
1112 /* Run custom bind function on netlink socket group connect or bind requests. */
1113 static int audit_bind(int group
)
1115 if (!capable(CAP_AUDIT_READ
))
1121 static int __net_init
audit_net_init(struct net
*net
)
1123 struct netlink_kernel_cfg cfg
= {
1124 .input
= audit_receive
,
1126 .flags
= NL_CFG_F_NONROOT_RECV
,
1127 .groups
= AUDIT_NLGRP_MAX
,
1130 struct audit_net
*aunet
= net_generic(net
, audit_net_id
);
1132 aunet
->nlsk
= netlink_kernel_create(net
, NETLINK_AUDIT
, &cfg
);
1133 if (aunet
->nlsk
== NULL
) {
1134 audit_panic("cannot initialize netlink socket in namespace");
1137 aunet
->nlsk
->sk_sndtimeo
= MAX_SCHEDULE_TIMEOUT
;
1141 static void __net_exit
audit_net_exit(struct net
*net
)
1143 struct audit_net
*aunet
= net_generic(net
, audit_net_id
);
1144 struct sock
*sock
= aunet
->nlsk
;
1145 if (sock
== audit_sock
) {
1150 RCU_INIT_POINTER(aunet
->nlsk
, NULL
);
1152 netlink_kernel_release(sock
);
1155 static struct pernet_operations audit_net_ops __net_initdata
= {
1156 .init
= audit_net_init
,
1157 .exit
= audit_net_exit
,
1158 .id
= &audit_net_id
,
1159 .size
= sizeof(struct audit_net
),
1162 /* Initialize audit support at boot time. */
1163 static int __init
audit_init(void)
1167 if (audit_initialized
== AUDIT_DISABLED
)
1170 pr_info("initializing netlink subsys (%s)\n",
1171 audit_default
? "enabled" : "disabled");
1172 register_pernet_subsys(&audit_net_ops
);
1174 skb_queue_head_init(&audit_skb_queue
);
1175 skb_queue_head_init(&audit_skb_hold_queue
);
1176 audit_initialized
= AUDIT_INITIALIZED
;
1177 audit_enabled
= audit_default
;
1178 audit_ever_enabled
|= !!audit_default
;
1180 audit_log(NULL
, GFP_KERNEL
, AUDIT_KERNEL
, "initialized");
1182 for (i
= 0; i
< AUDIT_INODE_BUCKETS
; i
++)
1183 INIT_LIST_HEAD(&audit_inode_hash
[i
]);
1187 __initcall(audit_init
);
1189 /* Process kernel command-line parameter at boot time. audit=0 or audit=1. */
1190 static int __init
audit_enable(char *str
)
1192 audit_default
= !!simple_strtol(str
, NULL
, 0);
1194 audit_initialized
= AUDIT_DISABLED
;
1196 pr_info("%s\n", audit_default
?
1197 "enabled (after initialization)" : "disabled (until reboot)");
1201 __setup("audit=", audit_enable
);
1203 /* Process kernel command-line parameter at boot time.
1204 * audit_backlog_limit=<n> */
1205 static int __init
audit_backlog_limit_set(char *str
)
1207 u32 audit_backlog_limit_arg
;
1209 pr_info("audit_backlog_limit: ");
1210 if (kstrtouint(str
, 0, &audit_backlog_limit_arg
)) {
1211 pr_cont("using default of %u, unable to parse %s\n",
1212 audit_backlog_limit
, str
);
1216 audit_backlog_limit
= audit_backlog_limit_arg
;
1217 pr_cont("%d\n", audit_backlog_limit
);
1221 __setup("audit_backlog_limit=", audit_backlog_limit_set
);
1223 static void audit_buffer_free(struct audit_buffer
*ab
)
1225 unsigned long flags
;
1233 spin_lock_irqsave(&audit_freelist_lock
, flags
);
1234 if (audit_freelist_count
> AUDIT_MAXFREE
)
1237 audit_freelist_count
++;
1238 list_add(&ab
->list
, &audit_freelist
);
1240 spin_unlock_irqrestore(&audit_freelist_lock
, flags
);
1243 static struct audit_buffer
* audit_buffer_alloc(struct audit_context
*ctx
,
1244 gfp_t gfp_mask
, int type
)
1246 unsigned long flags
;
1247 struct audit_buffer
*ab
= NULL
;
1248 struct nlmsghdr
*nlh
;
1250 spin_lock_irqsave(&audit_freelist_lock
, flags
);
1251 if (!list_empty(&audit_freelist
)) {
1252 ab
= list_entry(audit_freelist
.next
,
1253 struct audit_buffer
, list
);
1254 list_del(&ab
->list
);
1255 --audit_freelist_count
;
1257 spin_unlock_irqrestore(&audit_freelist_lock
, flags
);
1260 ab
= kmalloc(sizeof(*ab
), gfp_mask
);
1266 ab
->gfp_mask
= gfp_mask
;
1268 ab
->skb
= nlmsg_new(AUDIT_BUFSIZ
, gfp_mask
);
1272 nlh
= nlmsg_put(ab
->skb
, 0, 0, type
, 0, 0);
1282 audit_buffer_free(ab
);
1287 * audit_serial - compute a serial number for the audit record
1289 * Compute a serial number for the audit record. Audit records are
1290 * written to user-space as soon as they are generated, so a complete
1291 * audit record may be written in several pieces. The timestamp of the
1292 * record and this serial number are used by the user-space tools to
1293 * determine which pieces belong to the same audit record. The
1294 * (timestamp,serial) tuple is unique for each syscall and is live from
1295 * syscall entry to syscall exit.
1297 * NOTE: Another possibility is to store the formatted records off the
1298 * audit context (for those records that have a context), and emit them
1299 * all at syscall exit. However, this could delay the reporting of
1300 * significant errors until syscall exit (or never, if the system
1303 unsigned int audit_serial(void)
1305 static atomic_t serial
= ATOMIC_INIT(0);
1307 return atomic_add_return(1, &serial
);
1310 static inline void audit_get_stamp(struct audit_context
*ctx
,
1311 struct timespec
*t
, unsigned int *serial
)
1313 if (!ctx
|| !auditsc_get_stamp(ctx
, t
, serial
)) {
1315 *serial
= audit_serial();
1320 * Wait for auditd to drain the queue a little
1322 static long wait_for_auditd(long sleep_time
)
1324 DECLARE_WAITQUEUE(wait
, current
);
1325 set_current_state(TASK_UNINTERRUPTIBLE
);
1326 add_wait_queue_exclusive(&audit_backlog_wait
, &wait
);
1328 if (audit_backlog_limit
&&
1329 skb_queue_len(&audit_skb_queue
) > audit_backlog_limit
)
1330 sleep_time
= schedule_timeout(sleep_time
);
1332 __set_current_state(TASK_RUNNING
);
1333 remove_wait_queue(&audit_backlog_wait
, &wait
);
1339 * audit_log_start - obtain an audit buffer
1340 * @ctx: audit_context (may be NULL)
1341 * @gfp_mask: type of allocation
1342 * @type: audit message type
1344 * Returns audit_buffer pointer on success or NULL on error.
1346 * Obtain an audit buffer. This routine does locking to obtain the
1347 * audit buffer, but then no locking is required for calls to
1348 * audit_log_*format. If the task (ctx) is a task that is currently in a
1349 * syscall, then the syscall is marked as auditable and an audit record
1350 * will be written at syscall exit. If there is no associated task, then
1351 * task context (ctx) should be NULL.
1353 struct audit_buffer
*audit_log_start(struct audit_context
*ctx
, gfp_t gfp_mask
,
1356 struct audit_buffer
*ab
= NULL
;
1358 unsigned int uninitialized_var(serial
);
1359 int reserve
= 5; /* Allow atomic callers to go up to five
1360 entries over the normal backlog limit */
1361 unsigned long timeout_start
= jiffies
;
1363 if (audit_initialized
!= AUDIT_INITIALIZED
)
1366 if (unlikely(audit_filter_type(type
)))
1369 if (gfp_mask
& __GFP_WAIT
) {
1370 if (audit_pid
&& audit_pid
== current
->pid
)
1371 gfp_mask
&= ~__GFP_WAIT
;
1376 while (audit_backlog_limit
1377 && skb_queue_len(&audit_skb_queue
) > audit_backlog_limit
+ reserve
) {
1378 if (gfp_mask
& __GFP_WAIT
&& audit_backlog_wait_time
) {
1381 sleep_time
= timeout_start
+ audit_backlog_wait_time
- jiffies
;
1382 if (sleep_time
> 0) {
1383 sleep_time
= wait_for_auditd(sleep_time
);
1388 if (audit_rate_check() && printk_ratelimit())
1389 pr_warn("audit_backlog=%d > audit_backlog_limit=%d\n",
1390 skb_queue_len(&audit_skb_queue
),
1391 audit_backlog_limit
);
1392 audit_log_lost("backlog limit exceeded");
1393 audit_backlog_wait_time
= audit_backlog_wait_overflow
;
1394 wake_up(&audit_backlog_wait
);
1399 audit_backlog_wait_time
= audit_backlog_wait_time_master
;
1401 ab
= audit_buffer_alloc(ctx
, gfp_mask
, type
);
1403 audit_log_lost("out of memory in audit_log_start");
1407 audit_get_stamp(ab
->ctx
, &t
, &serial
);
1409 audit_log_format(ab
, "audit(%lu.%03lu:%u): ",
1410 t
.tv_sec
, t
.tv_nsec
/1000000, serial
);
1415 * audit_expand - expand skb in the audit buffer
1417 * @extra: space to add at tail of the skb
1419 * Returns 0 (no space) on failed expansion, or available space if
1422 static inline int audit_expand(struct audit_buffer
*ab
, int extra
)
1424 struct sk_buff
*skb
= ab
->skb
;
1425 int oldtail
= skb_tailroom(skb
);
1426 int ret
= pskb_expand_head(skb
, 0, extra
, ab
->gfp_mask
);
1427 int newtail
= skb_tailroom(skb
);
1430 audit_log_lost("out of memory in audit_expand");
1434 skb
->truesize
+= newtail
- oldtail
;
1439 * Format an audit message into the audit buffer. If there isn't enough
1440 * room in the audit buffer, more room will be allocated and vsnprint
1441 * will be called a second time. Currently, we assume that a printk
1442 * can't format message larger than 1024 bytes, so we don't either.
1444 static void audit_log_vformat(struct audit_buffer
*ab
, const char *fmt
,
1448 struct sk_buff
*skb
;
1456 avail
= skb_tailroom(skb
);
1458 avail
= audit_expand(ab
, AUDIT_BUFSIZ
);
1462 va_copy(args2
, args
);
1463 len
= vsnprintf(skb_tail_pointer(skb
), avail
, fmt
, args
);
1465 /* The printk buffer is 1024 bytes long, so if we get
1466 * here and AUDIT_BUFSIZ is at least 1024, then we can
1467 * log everything that printk could have logged. */
1468 avail
= audit_expand(ab
,
1469 max_t(unsigned, AUDIT_BUFSIZ
, 1+len
-avail
));
1472 len
= vsnprintf(skb_tail_pointer(skb
), avail
, fmt
, args2
);
1483 * audit_log_format - format a message into the audit buffer.
1485 * @fmt: format string
1486 * @...: optional parameters matching @fmt string
1488 * All the work is done in audit_log_vformat.
1490 void audit_log_format(struct audit_buffer
*ab
, const char *fmt
, ...)
1496 va_start(args
, fmt
);
1497 audit_log_vformat(ab
, fmt
, args
);
1502 * audit_log_hex - convert a buffer to hex and append it to the audit skb
1503 * @ab: the audit_buffer
1504 * @buf: buffer to convert to hex
1505 * @len: length of @buf to be converted
1507 * No return value; failure to expand is silently ignored.
1509 * This function will take the passed buf and convert it into a string of
1510 * ascii hex digits. The new string is placed onto the skb.
1512 void audit_log_n_hex(struct audit_buffer
*ab
, const unsigned char *buf
,
1515 int i
, avail
, new_len
;
1517 struct sk_buff
*skb
;
1524 avail
= skb_tailroom(skb
);
1526 if (new_len
>= avail
) {
1527 /* Round the buffer request up to the next multiple */
1528 new_len
= AUDIT_BUFSIZ
*(((new_len
-avail
)/AUDIT_BUFSIZ
) + 1);
1529 avail
= audit_expand(ab
, new_len
);
1534 ptr
= skb_tail_pointer(skb
);
1535 for (i
= 0; i
< len
; i
++)
1536 ptr
= hex_byte_pack_upper(ptr
, buf
[i
]);
1538 skb_put(skb
, len
<< 1); /* new string is twice the old string */
1542 * Format a string of no more than slen characters into the audit buffer,
1543 * enclosed in quote marks.
1545 void audit_log_n_string(struct audit_buffer
*ab
, const char *string
,
1550 struct sk_buff
*skb
;
1557 avail
= skb_tailroom(skb
);
1558 new_len
= slen
+ 3; /* enclosing quotes + null terminator */
1559 if (new_len
> avail
) {
1560 avail
= audit_expand(ab
, new_len
);
1564 ptr
= skb_tail_pointer(skb
);
1566 memcpy(ptr
, string
, slen
);
1570 skb_put(skb
, slen
+ 2); /* don't include null terminator */
1574 * audit_string_contains_control - does a string need to be logged in hex
1575 * @string: string to be checked
1576 * @len: max length of the string to check
1578 int audit_string_contains_control(const char *string
, size_t len
)
1580 const unsigned char *p
;
1581 for (p
= string
; p
< (const unsigned char *)string
+ len
; p
++) {
1582 if (*p
== '"' || *p
< 0x21 || *p
> 0x7e)
1589 * audit_log_n_untrustedstring - log a string that may contain random characters
1591 * @len: length of string (not including trailing null)
1592 * @string: string to be logged
1594 * This code will escape a string that is passed to it if the string
1595 * contains a control character, unprintable character, double quote mark,
1596 * or a space. Unescaped strings will start and end with a double quote mark.
1597 * Strings that are escaped are printed in hex (2 digits per char).
1599 * The caller specifies the number of characters in the string to log, which may
1600 * or may not be the entire string.
1602 void audit_log_n_untrustedstring(struct audit_buffer
*ab
, const char *string
,
1605 if (audit_string_contains_control(string
, len
))
1606 audit_log_n_hex(ab
, string
, len
);
1608 audit_log_n_string(ab
, string
, len
);
1612 * audit_log_untrustedstring - log a string that may contain random characters
1614 * @string: string to be logged
1616 * Same as audit_log_n_untrustedstring(), except that strlen is used to
1617 * determine string length.
1619 void audit_log_untrustedstring(struct audit_buffer
*ab
, const char *string
)
1621 audit_log_n_untrustedstring(ab
, string
, strlen(string
));
1624 /* This is a helper-function to print the escaped d_path */
1625 void audit_log_d_path(struct audit_buffer
*ab
, const char *prefix
,
1626 const struct path
*path
)
1631 audit_log_format(ab
, "%s", prefix
);
1633 /* We will allow 11 spaces for ' (deleted)' to be appended */
1634 pathname
= kmalloc(PATH_MAX
+11, ab
->gfp_mask
);
1636 audit_log_string(ab
, "<no_memory>");
1639 p
= d_path(path
, pathname
, PATH_MAX
+11);
1640 if (IS_ERR(p
)) { /* Should never happen since we send PATH_MAX */
1641 /* FIXME: can we save some information here? */
1642 audit_log_string(ab
, "<too_long>");
1644 audit_log_untrustedstring(ab
, p
);
1648 void audit_log_session_info(struct audit_buffer
*ab
)
1650 unsigned int sessionid
= audit_get_sessionid(current
);
1651 uid_t auid
= from_kuid(&init_user_ns
, audit_get_loginuid(current
));
1653 audit_log_format(ab
, " auid=%u ses=%u", auid
, sessionid
);
1656 void audit_log_key(struct audit_buffer
*ab
, char *key
)
1658 audit_log_format(ab
, " key=");
1660 audit_log_untrustedstring(ab
, key
);
1662 audit_log_format(ab
, "(null)");
1665 void audit_log_cap(struct audit_buffer
*ab
, char *prefix
, kernel_cap_t
*cap
)
1669 audit_log_format(ab
, " %s=", prefix
);
1670 CAP_FOR_EACH_U32(i
) {
1671 audit_log_format(ab
, "%08x",
1672 cap
->cap
[(_KERNEL_CAPABILITY_U32S
-1) - i
]);
1676 static void audit_log_fcaps(struct audit_buffer
*ab
, struct audit_names
*name
)
1678 kernel_cap_t
*perm
= &name
->fcap
.permitted
;
1679 kernel_cap_t
*inh
= &name
->fcap
.inheritable
;
1682 if (!cap_isclear(*perm
)) {
1683 audit_log_cap(ab
, "cap_fp", perm
);
1686 if (!cap_isclear(*inh
)) {
1687 audit_log_cap(ab
, "cap_fi", inh
);
1692 audit_log_format(ab
, " cap_fe=%d cap_fver=%x",
1693 name
->fcap
.fE
, name
->fcap_ver
);
1696 static inline int audit_copy_fcaps(struct audit_names
*name
,
1697 const struct dentry
*dentry
)
1699 struct cpu_vfs_cap_data caps
;
1705 rc
= get_vfs_caps_from_disk(dentry
, &caps
);
1709 name
->fcap
.permitted
= caps
.permitted
;
1710 name
->fcap
.inheritable
= caps
.inheritable
;
1711 name
->fcap
.fE
= !!(caps
.magic_etc
& VFS_CAP_FLAGS_EFFECTIVE
);
1712 name
->fcap_ver
= (caps
.magic_etc
& VFS_CAP_REVISION_MASK
) >>
1713 VFS_CAP_REVISION_SHIFT
;
1718 /* Copy inode data into an audit_names. */
1719 void audit_copy_inode(struct audit_names
*name
, const struct dentry
*dentry
,
1720 const struct inode
*inode
)
1722 name
->ino
= inode
->i_ino
;
1723 name
->dev
= inode
->i_sb
->s_dev
;
1724 name
->mode
= inode
->i_mode
;
1725 name
->uid
= inode
->i_uid
;
1726 name
->gid
= inode
->i_gid
;
1727 name
->rdev
= inode
->i_rdev
;
1728 security_inode_getsecid(inode
, &name
->osid
);
1729 audit_copy_fcaps(name
, dentry
);
1733 * audit_log_name - produce AUDIT_PATH record from struct audit_names
1734 * @context: audit_context for the task
1735 * @n: audit_names structure with reportable details
1736 * @path: optional path to report instead of audit_names->name
1737 * @record_num: record number to report when handling a list of names
1738 * @call_panic: optional pointer to int that will be updated if secid fails
1740 void audit_log_name(struct audit_context
*context
, struct audit_names
*n
,
1741 struct path
*path
, int record_num
, int *call_panic
)
1743 struct audit_buffer
*ab
;
1744 ab
= audit_log_start(context
, GFP_KERNEL
, AUDIT_PATH
);
1748 audit_log_format(ab
, "item=%d", record_num
);
1751 audit_log_d_path(ab
, " name=", path
);
1753 switch (n
->name_len
) {
1754 case AUDIT_NAME_FULL
:
1755 /* log the full path */
1756 audit_log_format(ab
, " name=");
1757 audit_log_untrustedstring(ab
, n
->name
->name
);
1760 /* name was specified as a relative path and the
1761 * directory component is the cwd */
1762 audit_log_d_path(ab
, " name=", &context
->pwd
);
1765 /* log the name's directory component */
1766 audit_log_format(ab
, " name=");
1767 audit_log_n_untrustedstring(ab
, n
->name
->name
,
1771 audit_log_format(ab
, " name=(null)");
1773 if (n
->ino
!= (unsigned long)-1)
1774 audit_log_format(ab
, " inode=%lu"
1775 " dev=%02x:%02x mode=%#ho"
1776 " ouid=%u ogid=%u rdev=%02x:%02x",
1781 from_kuid(&init_user_ns
, n
->uid
),
1782 from_kgid(&init_user_ns
, n
->gid
),
1788 if (security_secid_to_secctx(
1789 n
->osid
, &ctx
, &len
)) {
1790 audit_log_format(ab
, " osid=%u", n
->osid
);
1794 audit_log_format(ab
, " obj=%s", ctx
);
1795 security_release_secctx(ctx
, len
);
1799 /* log the audit_names record type */
1800 audit_log_format(ab
, " nametype=");
1802 case AUDIT_TYPE_NORMAL
:
1803 audit_log_format(ab
, "NORMAL");
1805 case AUDIT_TYPE_PARENT
:
1806 audit_log_format(ab
, "PARENT");
1808 case AUDIT_TYPE_CHILD_DELETE
:
1809 audit_log_format(ab
, "DELETE");
1811 case AUDIT_TYPE_CHILD_CREATE
:
1812 audit_log_format(ab
, "CREATE");
1815 audit_log_format(ab
, "UNKNOWN");
1819 audit_log_fcaps(ab
, n
);
1823 int audit_log_task_context(struct audit_buffer
*ab
)
1830 security_task_getsecid(current
, &sid
);
1834 error
= security_secid_to_secctx(sid
, &ctx
, &len
);
1836 if (error
!= -EINVAL
)
1841 audit_log_format(ab
, " subj=%s", ctx
);
1842 security_release_secctx(ctx
, len
);
1846 audit_panic("error in audit_log_task_context");
1849 EXPORT_SYMBOL(audit_log_task_context
);
1851 void audit_log_d_path_exe(struct audit_buffer
*ab
,
1852 struct mm_struct
*mm
)
1855 audit_log_format(ab
, " exe=(null)");
1859 down_read(&mm
->mmap_sem
);
1861 audit_log_d_path(ab
, " exe=", &mm
->exe_file
->f_path
);
1862 up_read(&mm
->mmap_sem
);
1865 void audit_log_task_info(struct audit_buffer
*ab
, struct task_struct
*tsk
)
1867 const struct cred
*cred
;
1868 char comm
[sizeof(tsk
->comm
)];
1874 /* tsk == current */
1875 cred
= current_cred();
1877 spin_lock_irq(&tsk
->sighand
->siglock
);
1878 if (tsk
->signal
&& tsk
->signal
->tty
&& tsk
->signal
->tty
->name
)
1879 tty
= tsk
->signal
->tty
->name
;
1882 spin_unlock_irq(&tsk
->sighand
->siglock
);
1884 audit_log_format(ab
,
1885 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1886 " euid=%u suid=%u fsuid=%u"
1887 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1890 from_kuid(&init_user_ns
, audit_get_loginuid(tsk
)),
1891 from_kuid(&init_user_ns
, cred
->uid
),
1892 from_kgid(&init_user_ns
, cred
->gid
),
1893 from_kuid(&init_user_ns
, cred
->euid
),
1894 from_kuid(&init_user_ns
, cred
->suid
),
1895 from_kuid(&init_user_ns
, cred
->fsuid
),
1896 from_kgid(&init_user_ns
, cred
->egid
),
1897 from_kgid(&init_user_ns
, cred
->sgid
),
1898 from_kgid(&init_user_ns
, cred
->fsgid
),
1899 tty
, audit_get_sessionid(tsk
));
1901 audit_log_format(ab
, " comm=");
1902 audit_log_untrustedstring(ab
, get_task_comm(comm
, tsk
));
1904 audit_log_d_path_exe(ab
, tsk
->mm
);
1905 audit_log_task_context(ab
);
1907 EXPORT_SYMBOL(audit_log_task_info
);
1910 * audit_log_link_denied - report a link restriction denial
1911 * @operation: specific link opreation
1912 * @link: the path that triggered the restriction
1914 void audit_log_link_denied(const char *operation
, struct path
*link
)
1916 struct audit_buffer
*ab
;
1917 struct audit_names
*name
;
1919 name
= kzalloc(sizeof(*name
), GFP_NOFS
);
1923 /* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */
1924 ab
= audit_log_start(current
->audit_context
, GFP_KERNEL
,
1928 audit_log_format(ab
, "op=%s", operation
);
1929 audit_log_task_info(ab
, current
);
1930 audit_log_format(ab
, " res=0");
1933 /* Generate AUDIT_PATH record with object. */
1934 name
->type
= AUDIT_TYPE_NORMAL
;
1935 audit_copy_inode(name
, link
->dentry
, link
->dentry
->d_inode
);
1936 audit_log_name(current
->audit_context
, name
, link
, 0, NULL
);
1942 * audit_log_end - end one audit record
1943 * @ab: the audit_buffer
1945 * netlink_unicast() cannot be called inside an irq context because it blocks
1946 * (last arg, flags, is not set to MSG_DONTWAIT), so the audit buffer is placed
1947 * on a queue and a tasklet is scheduled to remove them from the queue outside
1948 * the irq context. May be called in any context.
1950 void audit_log_end(struct audit_buffer
*ab
)
1954 if (!audit_rate_check()) {
1955 audit_log_lost("rate limit exceeded");
1957 struct nlmsghdr
*nlh
= nlmsg_hdr(ab
->skb
);
1959 nlh
->nlmsg_len
= ab
->skb
->len
;
1960 kauditd_send_multicast_skb(ab
->skb
, ab
->gfp_mask
);
1963 * The original kaudit unicast socket sends up messages with
1964 * nlmsg_len set to the payload length rather than the entire
1965 * message length. This breaks the standard set by netlink.
1966 * The existing auditd daemon assumes this breakage. Fixing
1967 * this would require co-ordinating a change in the established
1968 * protocol between the kaudit kernel subsystem and the auditd
1971 nlh
->nlmsg_len
-= NLMSG_HDRLEN
;
1974 skb_queue_tail(&audit_skb_queue
, ab
->skb
);
1975 wake_up_interruptible(&kauditd_wait
);
1977 audit_printk_skb(ab
->skb
);
1981 audit_buffer_free(ab
);
1985 * audit_log - Log an audit record
1986 * @ctx: audit context
1987 * @gfp_mask: type of allocation
1988 * @type: audit message type
1989 * @fmt: format string to use
1990 * @...: variable parameters matching the format string
1992 * This is a convenience function that calls audit_log_start,
1993 * audit_log_vformat, and audit_log_end. It may be called
1996 void audit_log(struct audit_context
*ctx
, gfp_t gfp_mask
, int type
,
1997 const char *fmt
, ...)
1999 struct audit_buffer
*ab
;
2002 ab
= audit_log_start(ctx
, gfp_mask
, type
);
2004 va_start(args
, fmt
);
2005 audit_log_vformat(ab
, fmt
, args
);
2011 #ifdef CONFIG_SECURITY
2013 * audit_log_secctx - Converts and logs SELinux context
2015 * @secid: security number
2017 * This is a helper function that calls security_secid_to_secctx to convert
2018 * secid to secctx and then adds the (converted) SELinux context to the audit
2019 * log by calling audit_log_format, thus also preventing leak of internal secid
2020 * to userspace. If secid cannot be converted audit_panic is called.
2022 void audit_log_secctx(struct audit_buffer
*ab
, u32 secid
)
2027 if (security_secid_to_secctx(secid
, &secctx
, &len
)) {
2028 audit_panic("Cannot convert secid to context");
2030 audit_log_format(ab
, " obj=%s", secctx
);
2031 security_release_secctx(secctx
, len
);
2034 EXPORT_SYMBOL(audit_log_secctx
);
2037 EXPORT_SYMBOL(audit_log_start
);
2038 EXPORT_SYMBOL(audit_log_end
);
2039 EXPORT_SYMBOL(audit_log_format
);
2040 EXPORT_SYMBOL(audit_log
);