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 #include <linux/init.h>
45 #include <asm/types.h>
46 #include <linux/atomic.h>
48 #include <linux/export.h>
49 #include <linux/slab.h>
50 #include <linux/err.h>
51 #include <linux/kthread.h>
52 #include <linux/kernel.h>
53 #include <linux/syscalls.h>
55 #include <linux/audit.h>
58 #include <net/netlink.h>
59 #include <linux/skbuff.h>
60 #ifdef CONFIG_SECURITY
61 #include <linux/security.h>
63 #include <linux/freezer.h>
64 #include <linux/tty.h>
65 #include <linux/pid_namespace.h>
66 #include <net/netns/generic.h>
70 /* No auditing will take place until audit_initialized == AUDIT_INITIALIZED.
71 * (Initialization happens after skb_init is called.) */
72 #define AUDIT_DISABLED -1
73 #define AUDIT_UNINITIALIZED 0
74 #define AUDIT_INITIALIZED 1
75 static int audit_initialized;
79 #define AUDIT_LOCKED 2
81 int audit_ever_enabled;
83 EXPORT_SYMBOL_GPL(audit_enabled);
85 /* Default state when kernel boots without any parameters. */
86 static int audit_default;
88 /* If auditing cannot proceed, audit_failure selects what happens. */
89 static int audit_failure = AUDIT_FAIL_PRINTK;
92 * If audit records are to be written to the netlink socket, audit_pid
93 * contains the pid of the auditd process and audit_nlk_portid contains
94 * the portid to use to send netlink messages to that process.
97 static __u32 audit_nlk_portid;
99 /* If audit_rate_limit is non-zero, limit the rate of sending audit records
100 * to that number per second. This prevents DoS attacks, but results in
101 * audit records being dropped. */
102 static int audit_rate_limit;
104 /* Number of outstanding audit_buffers allowed. */
105 static int audit_backlog_limit = 64;
106 #define AUDIT_BACKLOG_WAIT_TIME (60 * HZ)
107 static int audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
108 static int audit_backlog_wait_overflow = 0;
110 /* The identity of the user shutting down the audit system. */
111 kuid_t audit_sig_uid = INVALID_UID;
112 pid_t audit_sig_pid = -1;
113 u32 audit_sig_sid = 0;
115 /* Records can be lost in several ways:
116 0) [suppressed in audit_alloc]
117 1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
118 2) out of memory in audit_log_move [alloc_skb]
119 3) suppressed due to audit_rate_limit
120 4) suppressed due to audit_backlog_limit
122 static atomic_t audit_lost = ATOMIC_INIT(0);
124 /* The netlink socket. */
125 static struct sock *audit_sock;
128 /* Hash for inode-based rules */
129 struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
131 /* The audit_freelist is a list of pre-allocated audit buffers (if more
132 * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
133 * being placed on the freelist). */
134 static DEFINE_SPINLOCK(audit_freelist_lock);
135 static int audit_freelist_count;
136 static LIST_HEAD(audit_freelist);
138 static struct sk_buff_head audit_skb_queue;
139 /* queue of skbs to send to auditd when/if it comes back */
140 static struct sk_buff_head audit_skb_hold_queue;
141 static struct task_struct *kauditd_task;
142 static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
143 static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
145 static struct audit_features af = {.vers = AUDIT_FEATURE_VERSION,
150 static char *audit_feature_names[2] = {
151 "only_unset_loginuid",
152 "loginuid_immutable",
156 /* Serialize requests from userspace. */
157 DEFINE_MUTEX(audit_cmd_mutex);
159 /* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
160 * audit records. Since printk uses a 1024 byte buffer, this buffer
161 * should be at least that large. */
162 #define AUDIT_BUFSIZ 1024
164 /* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the
165 * audit_freelist. Doing so eliminates many kmalloc/kfree calls. */
166 #define AUDIT_MAXFREE (2*NR_CPUS)
168 /* The audit_buffer is used when formatting an audit record. The caller
169 * locks briefly to get the record off the freelist or to allocate the
170 * buffer, and locks briefly to send the buffer to the netlink layer or
171 * to place it on a transmit queue. Multiple audit_buffers can be in
172 * use simultaneously. */
173 struct audit_buffer {
174 struct list_head list;
175 struct sk_buff *skb; /* formatted skb ready to send */
176 struct audit_context *ctx; /* NULL or associated context */
186 static void audit_set_portid(struct audit_buffer *ab, __u32 portid)
189 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
190 nlh->nlmsg_pid = portid;
194 void audit_panic(const char *message)
196 switch (audit_failure)
198 case AUDIT_FAIL_SILENT:
200 case AUDIT_FAIL_PRINTK:
201 if (printk_ratelimit())
202 printk(KERN_ERR "audit: %s\n", message);
204 case AUDIT_FAIL_PANIC:
205 /* test audit_pid since printk is always losey, why bother? */
207 panic("audit: %s\n", message);
212 static inline int audit_rate_check(void)
214 static unsigned long last_check = 0;
215 static int messages = 0;
216 static DEFINE_SPINLOCK(lock);
219 unsigned long elapsed;
222 if (!audit_rate_limit) return 1;
224 spin_lock_irqsave(&lock, flags);
225 if (++messages < audit_rate_limit) {
229 elapsed = now - last_check;
236 spin_unlock_irqrestore(&lock, flags);
242 * audit_log_lost - conditionally log lost audit message event
243 * @message: the message stating reason for lost audit message
245 * Emit at least 1 message per second, even if audit_rate_check is
247 * Always increment the lost messages counter.
249 void audit_log_lost(const char *message)
251 static unsigned long last_msg = 0;
252 static DEFINE_SPINLOCK(lock);
257 atomic_inc(&audit_lost);
259 print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit);
262 spin_lock_irqsave(&lock, flags);
264 if (now - last_msg > HZ) {
268 spin_unlock_irqrestore(&lock, flags);
272 if (printk_ratelimit())
274 "audit: audit_lost=%d audit_rate_limit=%d "
275 "audit_backlog_limit=%d\n",
276 atomic_read(&audit_lost),
278 audit_backlog_limit);
279 audit_panic(message);
283 static int audit_log_config_change(char *function_name, int new, int old,
286 struct audit_buffer *ab;
289 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
292 audit_log_format(ab, "%s=%d old=%d", function_name, new, old);
293 audit_log_session_info(ab);
294 rc = audit_log_task_context(ab);
296 allow_changes = 0; /* Something weird, deny request */
297 audit_log_format(ab, " res=%d", allow_changes);
302 static int audit_do_config_change(char *function_name, int *to_change, int new)
304 int allow_changes, rc = 0, old = *to_change;
306 /* check if we are locked */
307 if (audit_enabled == AUDIT_LOCKED)
312 if (audit_enabled != AUDIT_OFF) {
313 rc = audit_log_config_change(function_name, new, old, allow_changes);
318 /* If we are allowed, make the change */
319 if (allow_changes == 1)
321 /* Not allowed, update reason */
327 static int audit_set_rate_limit(int limit)
329 return audit_do_config_change("audit_rate_limit", &audit_rate_limit, limit);
332 static int audit_set_backlog_limit(int limit)
334 return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, limit);
337 static int audit_set_enabled(int state)
340 if (state < AUDIT_OFF || state > AUDIT_LOCKED)
343 rc = audit_do_config_change("audit_enabled", &audit_enabled, state);
345 audit_ever_enabled |= !!state;
350 static int audit_set_failure(int state)
352 if (state != AUDIT_FAIL_SILENT
353 && state != AUDIT_FAIL_PRINTK
354 && state != AUDIT_FAIL_PANIC)
357 return audit_do_config_change("audit_failure", &audit_failure, state);
361 * Queue skbs to be sent to auditd when/if it comes back. These skbs should
362 * already have been sent via prink/syslog and so if these messages are dropped
363 * it is not a huge concern since we already passed the audit_log_lost()
364 * notification and stuff. This is just nice to get audit messages during
365 * boot before auditd is running or messages generated while auditd is stopped.
366 * This only holds messages is audit_default is set, aka booting with audit=1
367 * or building your kernel that way.
369 static void audit_hold_skb(struct sk_buff *skb)
372 skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit)
373 skb_queue_tail(&audit_skb_hold_queue, skb);
379 * For one reason or another this nlh isn't getting delivered to the userspace
380 * audit daemon, just send it to printk.
382 static void audit_printk_skb(struct sk_buff *skb)
384 struct nlmsghdr *nlh = nlmsg_hdr(skb);
385 char *data = nlmsg_data(nlh);
387 if (nlh->nlmsg_type != AUDIT_EOE) {
388 if (printk_ratelimit())
389 printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, data);
391 audit_log_lost("printk limit exceeded\n");
397 static void kauditd_send_skb(struct sk_buff *skb)
400 /* take a reference in case we can't send it and we want to hold it */
402 err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0);
404 BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
405 printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
406 audit_log_lost("auditd disappeared\n");
409 /* we might get lucky and get this in the next auditd */
412 /* drop the extra reference if sent ok */
417 * flush_hold_queue - empty the hold queue if auditd appears
419 * If auditd just started, drain the queue of messages already
420 * sent to syslog/printk. Remember loss here is ok. We already
421 * called audit_log_lost() if it didn't go out normally. so the
422 * race between the skb_dequeue and the next check for audit_pid
425 * If you ever find kauditd to be too slow we can get a perf win
426 * by doing our own locking and keeping better track if there
427 * are messages in this queue. I don't see the need now, but
428 * in 5 years when I want to play with this again I'll see this
429 * note and still have no friggin idea what i'm thinking today.
431 static void flush_hold_queue(void)
435 if (!audit_default || !audit_pid)
438 skb = skb_dequeue(&audit_skb_hold_queue);
442 while (skb && audit_pid) {
443 kauditd_send_skb(skb);
444 skb = skb_dequeue(&audit_skb_hold_queue);
448 * if auditd just disappeared but we
449 * dequeued an skb we need to drop ref
455 static int kauditd_thread(void *dummy)
458 while (!kthread_should_stop()) {
460 DECLARE_WAITQUEUE(wait, current);
464 skb = skb_dequeue(&audit_skb_queue);
467 if (skb_queue_len(&audit_skb_queue) <= audit_backlog_limit)
468 wake_up(&audit_backlog_wait);
470 kauditd_send_skb(skb);
472 audit_printk_skb(skb);
475 set_current_state(TASK_INTERRUPTIBLE);
476 add_wait_queue(&kauditd_wait, &wait);
478 if (!skb_queue_len(&audit_skb_queue)) {
483 __set_current_state(TASK_RUNNING);
484 remove_wait_queue(&kauditd_wait, &wait);
489 int audit_send_list(void *_dest)
491 struct audit_netlink_list *dest = _dest;
493 struct net *net = get_net_ns_by_pid(dest->pid);
494 struct audit_net *aunet = net_generic(net, audit_net_id);
496 /* wait for parent to finish and send an ACK */
497 mutex_lock(&audit_cmd_mutex);
498 mutex_unlock(&audit_cmd_mutex);
500 while ((skb = __skb_dequeue(&dest->q)) != NULL)
501 netlink_unicast(aunet->nlsk, skb, dest->portid, 0);
508 struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, int done,
509 int multi, const void *payload, int size)
512 struct nlmsghdr *nlh;
514 int flags = multi ? NLM_F_MULTI : 0;
515 int t = done ? NLMSG_DONE : type;
517 skb = nlmsg_new(size, GFP_KERNEL);
521 nlh = nlmsg_put(skb, portid, seq, t, size, flags);
524 data = nlmsg_data(nlh);
525 memcpy(data, payload, size);
533 static int audit_send_reply_thread(void *arg)
535 struct audit_reply *reply = (struct audit_reply *)arg;
536 struct net *net = get_net_ns_by_pid(reply->pid);
537 struct audit_net *aunet = net_generic(net, audit_net_id);
539 mutex_lock(&audit_cmd_mutex);
540 mutex_unlock(&audit_cmd_mutex);
542 /* Ignore failure. It'll only happen if the sender goes away,
543 because our timeout is set to infinite. */
544 netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0);
549 * audit_send_reply - send an audit reply message via netlink
550 * @portid: netlink port to which to send reply
551 * @seq: sequence number
552 * @type: audit message type
553 * @done: done (last) flag
554 * @multi: multi-part message flag
555 * @payload: payload data
556 * @size: payload size
558 * Allocates an skb, builds the netlink message, and sends it to the port id.
559 * No failure notifications.
561 static void audit_send_reply(__u32 portid, int seq, int type, int done,
562 int multi, const void *payload, int size)
565 struct task_struct *tsk;
566 struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
572 skb = audit_make_reply(portid, seq, type, done, multi, payload, size);
576 reply->portid = portid;
577 reply->pid = task_pid_vnr(current);
580 tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
589 * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
592 static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
596 /* Only support the initial namespaces for now. */
597 if ((current_user_ns() != &init_user_ns) ||
598 (task_active_pid_ns(current) != &init_pid_ns))
608 case AUDIT_GET_FEATURE:
609 case AUDIT_SET_FEATURE:
610 case AUDIT_LIST_RULES:
613 case AUDIT_SIGNAL_INFO:
617 case AUDIT_MAKE_EQUIV:
618 if (!capable(CAP_AUDIT_CONTROL))
622 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
623 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
624 if (!capable(CAP_AUDIT_WRITE))
627 default: /* bad msg */
634 static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
637 uid_t uid = from_kuid(&init_user_ns, current_uid());
639 if (!audit_enabled && msg_type != AUDIT_USER_AVC) {
644 *ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
647 audit_log_format(*ab, "pid=%d uid=%u", task_tgid_vnr(current), uid);
648 audit_log_session_info(*ab);
649 audit_log_task_context(*ab);
654 int is_audit_feature_set(int i)
656 return af.features & AUDIT_FEATURE_TO_MASK(i);
660 static int audit_get_feature(struct sk_buff *skb)
664 seq = nlmsg_hdr(skb)->nlmsg_seq;
666 audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0,
672 static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature,
673 u32 old_lock, u32 new_lock, int res)
675 struct audit_buffer *ab;
677 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE);
678 audit_log_format(ab, "feature=%s new=%d old=%d old_lock=%d new_lock=%d res=%d",
679 audit_feature_names[which], !!old_feature, !!new_feature,
680 !!old_lock, !!new_lock, res);
684 static int audit_set_feature(struct sk_buff *skb)
686 struct audit_features *uaf;
689 BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > sizeof(audit_feature_names)/sizeof(audit_feature_names[0]));
690 uaf = nlmsg_data(nlmsg_hdr(skb));
692 /* if there is ever a version 2 we should handle that here */
694 for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
695 u32 feature = AUDIT_FEATURE_TO_MASK(i);
696 u32 old_feature, new_feature, old_lock, new_lock;
698 /* if we are not changing this feature, move along */
699 if (!(feature & uaf->mask))
702 old_feature = af.features & feature;
703 new_feature = uaf->features & feature;
704 new_lock = (uaf->lock | af.lock) & feature;
705 old_lock = af.lock & feature;
707 /* are we changing a locked feature? */
708 if ((af.lock & feature) && (new_feature != old_feature)) {
709 audit_log_feature_change(i, old_feature, new_feature,
710 old_lock, new_lock, 0);
714 /* nothing invalid, do the changes */
715 for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
716 u32 feature = AUDIT_FEATURE_TO_MASK(i);
717 u32 old_feature, new_feature, old_lock, new_lock;
719 /* if we are not changing this feature, move along */
720 if (!(feature & uaf->mask))
723 old_feature = af.features & feature;
724 new_feature = uaf->features & feature;
725 old_lock = af.lock & feature;
726 new_lock = (uaf->lock | af.lock) & feature;
728 if (new_feature != old_feature)
729 audit_log_feature_change(i, old_feature, new_feature,
730 old_lock, new_lock, 1);
733 af.features |= feature;
735 af.features &= ~feature;
742 static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
746 struct audit_status *status_get, status_set;
748 struct audit_buffer *ab;
749 u16 msg_type = nlh->nlmsg_type;
750 struct audit_sig_info *sig_data;
754 err = audit_netlink_ok(skb, msg_type);
758 /* As soon as there's any sign of userspace auditd,
759 * start kauditd to talk to it */
761 kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
762 if (IS_ERR(kauditd_task)) {
763 err = PTR_ERR(kauditd_task);
768 seq = nlh->nlmsg_seq;
769 data = nlmsg_data(nlh);
773 memset(&status_set, 0, sizeof(status_set));
774 status_set.enabled = audit_enabled;
775 status_set.failure = audit_failure;
776 status_set.pid = audit_pid;
777 status_set.rate_limit = audit_rate_limit;
778 status_set.backlog_limit = audit_backlog_limit;
779 status_set.lost = atomic_read(&audit_lost);
780 status_set.backlog = skb_queue_len(&audit_skb_queue);
781 audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0,
782 &status_set, sizeof(status_set));
785 if (nlmsg_len(nlh) < sizeof(struct audit_status))
787 status_get = (struct audit_status *)data;
788 if (status_get->mask & AUDIT_STATUS_ENABLED) {
789 err = audit_set_enabled(status_get->enabled);
793 if (status_get->mask & AUDIT_STATUS_FAILURE) {
794 err = audit_set_failure(status_get->failure);
798 if (status_get->mask & AUDIT_STATUS_PID) {
799 int new_pid = status_get->pid;
801 if (audit_enabled != AUDIT_OFF)
802 audit_log_config_change("audit_pid", new_pid, audit_pid, 1);
804 audit_nlk_portid = NETLINK_CB(skb).portid;
805 audit_sock = NETLINK_CB(skb).sk;
807 if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) {
808 err = audit_set_rate_limit(status_get->rate_limit);
812 if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
813 err = audit_set_backlog_limit(status_get->backlog_limit);
815 case AUDIT_GET_FEATURE:
816 err = audit_get_feature(skb);
820 case AUDIT_SET_FEATURE:
821 err = audit_set_feature(skb);
826 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
827 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
828 if (!audit_enabled && msg_type != AUDIT_USER_AVC)
831 err = audit_filter_user(msg_type);
834 if (msg_type == AUDIT_USER_TTY) {
835 err = tty_audit_push_current();
839 audit_log_common_recv_msg(&ab, msg_type);
840 if (msg_type != AUDIT_USER_TTY)
841 audit_log_format(ab, " msg='%.*s'",
842 AUDIT_MESSAGE_TEXT_MAX,
847 audit_log_format(ab, " data=");
848 size = nlmsg_len(nlh);
850 ((unsigned char *)data)[size - 1] == '\0')
852 audit_log_n_untrustedstring(ab, data, size);
854 audit_set_portid(ab, NETLINK_CB(skb).portid);
860 if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
862 if (audit_enabled == AUDIT_LOCKED) {
863 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
864 audit_log_format(ab, " audit_enabled=%d res=0", audit_enabled);
869 case AUDIT_LIST_RULES:
870 err = audit_receive_filter(msg_type, NETLINK_CB(skb).portid,
871 seq, data, nlmsg_len(nlh));
875 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
876 audit_log_format(ab, " op=trim res=1");
879 case AUDIT_MAKE_EQUIV: {
882 size_t msglen = nlmsg_len(nlh);
886 if (msglen < 2 * sizeof(u32))
888 memcpy(sizes, bufp, 2 * sizeof(u32));
889 bufp += 2 * sizeof(u32);
890 msglen -= 2 * sizeof(u32);
891 old = audit_unpack_string(&bufp, &msglen, sizes[0]);
896 new = audit_unpack_string(&bufp, &msglen, sizes[1]);
902 /* OK, here comes... */
903 err = audit_tag_tree(old, new);
905 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
907 audit_log_format(ab, " op=make_equiv old=");
908 audit_log_untrustedstring(ab, old);
909 audit_log_format(ab, " new=");
910 audit_log_untrustedstring(ab, new);
911 audit_log_format(ab, " res=%d", !err);
917 case AUDIT_SIGNAL_INFO:
920 err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
924 sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
927 security_release_secctx(ctx, len);
930 sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
931 sig_data->pid = audit_sig_pid;
933 memcpy(sig_data->ctx, ctx, len);
934 security_release_secctx(ctx, len);
936 audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_SIGNAL_INFO,
937 0, 0, sig_data, sizeof(*sig_data) + len);
940 case AUDIT_TTY_GET: {
941 struct audit_tty_status s;
942 struct task_struct *tsk = current;
944 spin_lock(&tsk->sighand->siglock);
945 s.enabled = tsk->signal->audit_tty;
946 s.log_passwd = tsk->signal->audit_tty_log_passwd;
947 spin_unlock(&tsk->sighand->siglock);
949 audit_send_reply(NETLINK_CB(skb).portid, seq,
950 AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
953 case AUDIT_TTY_SET: {
954 struct audit_tty_status s;
955 struct task_struct *tsk = current;
957 memset(&s, 0, sizeof(s));
958 /* guard against past and future API changes */
959 memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
960 if ((s.enabled != 0 && s.enabled != 1) ||
961 (s.log_passwd != 0 && s.log_passwd != 1))
964 spin_lock(&tsk->sighand->siglock);
965 tsk->signal->audit_tty = s.enabled;
966 tsk->signal->audit_tty_log_passwd = s.log_passwd;
967 spin_unlock(&tsk->sighand->siglock);
975 return err < 0 ? err : 0;
979 * Get message from skb. Each message is processed by audit_receive_msg.
980 * Malformed skbs with wrong length are discarded silently.
982 static void audit_receive_skb(struct sk_buff *skb)
984 struct nlmsghdr *nlh;
986 * len MUST be signed for nlmsg_next to be able to dec it below 0
987 * if the nlmsg_len was not aligned
992 nlh = nlmsg_hdr(skb);
995 while (nlmsg_ok(nlh, len)) {
996 err = audit_receive_msg(skb, nlh);
997 /* if err or if this message says it wants a response */
998 if (err || (nlh->nlmsg_flags & NLM_F_ACK))
999 netlink_ack(skb, nlh, err);
1001 nlh = nlmsg_next(nlh, &len);
1005 /* Receive messages from netlink socket. */
1006 static void audit_receive(struct sk_buff *skb)
1008 mutex_lock(&audit_cmd_mutex);
1009 audit_receive_skb(skb);
1010 mutex_unlock(&audit_cmd_mutex);
1013 static int __net_init audit_net_init(struct net *net)
1015 struct netlink_kernel_cfg cfg = {
1016 .input = audit_receive,
1019 struct audit_net *aunet = net_generic(net, audit_net_id);
1021 pr_info("audit: initializing netlink socket in namespace\n");
1023 aunet->nlsk = netlink_kernel_create(net, NETLINK_AUDIT, &cfg);
1024 if (aunet->nlsk == NULL)
1027 audit_panic("cannot initialize netlink socket in namespace");
1029 aunet->nlsk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
1033 static void __net_exit audit_net_exit(struct net *net)
1035 struct audit_net *aunet = net_generic(net, audit_net_id);
1036 struct sock *sock = aunet->nlsk;
1037 if (sock == audit_sock) {
1042 rcu_assign_pointer(aunet->nlsk, NULL);
1044 netlink_kernel_release(sock);
1047 static struct pernet_operations __net_initdata audit_net_ops = {
1048 .init = audit_net_init,
1049 .exit = audit_net_exit,
1050 .id = &audit_net_id,
1051 .size = sizeof(struct audit_net),
1054 /* Initialize audit support at boot time. */
1055 static int __init audit_init(void)
1059 if (audit_initialized == AUDIT_DISABLED)
1062 pr_info("audit: initializing netlink subsys (%s)\n",
1063 audit_default ? "enabled" : "disabled");
1064 register_pernet_subsys(&audit_net_ops);
1066 skb_queue_head_init(&audit_skb_queue);
1067 skb_queue_head_init(&audit_skb_hold_queue);
1068 audit_initialized = AUDIT_INITIALIZED;
1069 audit_enabled = audit_default;
1070 audit_ever_enabled |= !!audit_default;
1072 audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
1074 for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
1075 INIT_LIST_HEAD(&audit_inode_hash[i]);
1079 __initcall(audit_init);
1081 /* Process kernel command-line parameter at boot time. audit=0 or audit=1. */
1082 static int __init audit_enable(char *str)
1084 audit_default = !!simple_strtol(str, NULL, 0);
1086 audit_initialized = AUDIT_DISABLED;
1088 printk(KERN_INFO "audit: %s", audit_default ? "enabled" : "disabled");
1090 if (audit_initialized == AUDIT_INITIALIZED) {
1091 audit_enabled = audit_default;
1092 audit_ever_enabled |= !!audit_default;
1093 } else if (audit_initialized == AUDIT_UNINITIALIZED) {
1094 printk(" (after initialization)");
1096 printk(" (until reboot)");
1103 __setup("audit=", audit_enable);
1105 static void audit_buffer_free(struct audit_buffer *ab)
1107 unsigned long flags;
1115 spin_lock_irqsave(&audit_freelist_lock, flags);
1116 if (audit_freelist_count > AUDIT_MAXFREE)
1119 audit_freelist_count++;
1120 list_add(&ab->list, &audit_freelist);
1122 spin_unlock_irqrestore(&audit_freelist_lock, flags);
1125 static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
1126 gfp_t gfp_mask, int type)
1128 unsigned long flags;
1129 struct audit_buffer *ab = NULL;
1130 struct nlmsghdr *nlh;
1132 spin_lock_irqsave(&audit_freelist_lock, flags);
1133 if (!list_empty(&audit_freelist)) {
1134 ab = list_entry(audit_freelist.next,
1135 struct audit_buffer, list);
1136 list_del(&ab->list);
1137 --audit_freelist_count;
1139 spin_unlock_irqrestore(&audit_freelist_lock, flags);
1142 ab = kmalloc(sizeof(*ab), gfp_mask);
1148 ab->gfp_mask = gfp_mask;
1150 ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask);
1154 nlh = nlmsg_put(ab->skb, 0, 0, type, 0, 0);
1164 audit_buffer_free(ab);
1169 * audit_serial - compute a serial number for the audit record
1171 * Compute a serial number for the audit record. Audit records are
1172 * written to user-space as soon as they are generated, so a complete
1173 * audit record may be written in several pieces. The timestamp of the
1174 * record and this serial number are used by the user-space tools to
1175 * determine which pieces belong to the same audit record. The
1176 * (timestamp,serial) tuple is unique for each syscall and is live from
1177 * syscall entry to syscall exit.
1179 * NOTE: Another possibility is to store the formatted records off the
1180 * audit context (for those records that have a context), and emit them
1181 * all at syscall exit. However, this could delay the reporting of
1182 * significant errors until syscall exit (or never, if the system
1185 unsigned int audit_serial(void)
1187 static DEFINE_SPINLOCK(serial_lock);
1188 static unsigned int serial = 0;
1190 unsigned long flags;
1193 spin_lock_irqsave(&serial_lock, flags);
1196 } while (unlikely(!ret));
1197 spin_unlock_irqrestore(&serial_lock, flags);
1202 static inline void audit_get_stamp(struct audit_context *ctx,
1203 struct timespec *t, unsigned int *serial)
1205 if (!ctx || !auditsc_get_stamp(ctx, t, serial)) {
1207 *serial = audit_serial();
1212 * Wait for auditd to drain the queue a little
1214 static unsigned long wait_for_auditd(unsigned long sleep_time)
1216 unsigned long timeout = sleep_time;
1217 DECLARE_WAITQUEUE(wait, current);
1218 set_current_state(TASK_UNINTERRUPTIBLE);
1219 add_wait_queue_exclusive(&audit_backlog_wait, &wait);
1221 if (audit_backlog_limit &&
1222 skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
1223 timeout = schedule_timeout(sleep_time);
1225 __set_current_state(TASK_RUNNING);
1226 remove_wait_queue(&audit_backlog_wait, &wait);
1232 * audit_log_start - obtain an audit buffer
1233 * @ctx: audit_context (may be NULL)
1234 * @gfp_mask: type of allocation
1235 * @type: audit message type
1237 * Returns audit_buffer pointer on success or NULL on error.
1239 * Obtain an audit buffer. This routine does locking to obtain the
1240 * audit buffer, but then no locking is required for calls to
1241 * audit_log_*format. If the task (ctx) is a task that is currently in a
1242 * syscall, then the syscall is marked as auditable and an audit record
1243 * will be written at syscall exit. If there is no associated task, then
1244 * task context (ctx) should be NULL.
1246 struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
1249 struct audit_buffer *ab = NULL;
1251 unsigned int uninitialized_var(serial);
1253 unsigned long timeout_start = jiffies;
1255 if (audit_initialized != AUDIT_INITIALIZED)
1258 if (unlikely(audit_filter_type(type)))
1261 if (gfp_mask & __GFP_WAIT)
1264 reserve = 5; /* Allow atomic callers to go up to five
1265 entries over the normal backlog limit */
1267 while (audit_backlog_limit
1268 && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
1269 if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) {
1270 unsigned long sleep_time;
1272 sleep_time = timeout_start + audit_backlog_wait_time -
1274 if ((long)sleep_time > 0) {
1275 sleep_time = wait_for_auditd(sleep_time);
1276 if ((long)sleep_time > 0)
1280 if (audit_rate_check() && printk_ratelimit())
1282 "audit: audit_backlog=%d > "
1283 "audit_backlog_limit=%d\n",
1284 skb_queue_len(&audit_skb_queue),
1285 audit_backlog_limit);
1286 audit_log_lost("backlog limit exceeded");
1287 audit_backlog_wait_time = audit_backlog_wait_overflow;
1288 wake_up(&audit_backlog_wait);
1292 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
1294 ab = audit_buffer_alloc(ctx, gfp_mask, type);
1296 audit_log_lost("out of memory in audit_log_start");
1300 audit_get_stamp(ab->ctx, &t, &serial);
1302 audit_log_format(ab, "audit(%lu.%03lu:%u): ",
1303 t.tv_sec, t.tv_nsec/1000000, serial);
1308 * audit_expand - expand skb in the audit buffer
1310 * @extra: space to add at tail of the skb
1312 * Returns 0 (no space) on failed expansion, or available space if
1315 static inline int audit_expand(struct audit_buffer *ab, int extra)
1317 struct sk_buff *skb = ab->skb;
1318 int oldtail = skb_tailroom(skb);
1319 int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask);
1320 int newtail = skb_tailroom(skb);
1323 audit_log_lost("out of memory in audit_expand");
1327 skb->truesize += newtail - oldtail;
1332 * Format an audit message into the audit buffer. If there isn't enough
1333 * room in the audit buffer, more room will be allocated and vsnprint
1334 * will be called a second time. Currently, we assume that a printk
1335 * can't format message larger than 1024 bytes, so we don't either.
1337 static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
1341 struct sk_buff *skb;
1349 avail = skb_tailroom(skb);
1351 avail = audit_expand(ab, AUDIT_BUFSIZ);
1355 va_copy(args2, args);
1356 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args);
1358 /* The printk buffer is 1024 bytes long, so if we get
1359 * here and AUDIT_BUFSIZ is at least 1024, then we can
1360 * log everything that printk could have logged. */
1361 avail = audit_expand(ab,
1362 max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
1365 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2);
1376 * audit_log_format - format a message into the audit buffer.
1378 * @fmt: format string
1379 * @...: optional parameters matching @fmt string
1381 * All the work is done in audit_log_vformat.
1383 void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
1389 va_start(args, fmt);
1390 audit_log_vformat(ab, fmt, args);
1395 * audit_log_hex - convert a buffer to hex and append it to the audit skb
1396 * @ab: the audit_buffer
1397 * @buf: buffer to convert to hex
1398 * @len: length of @buf to be converted
1400 * No return value; failure to expand is silently ignored.
1402 * This function will take the passed buf and convert it into a string of
1403 * ascii hex digits. The new string is placed onto the skb.
1405 void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
1408 int i, avail, new_len;
1410 struct sk_buff *skb;
1411 static const unsigned char *hex = "0123456789ABCDEF";
1418 avail = skb_tailroom(skb);
1420 if (new_len >= avail) {
1421 /* Round the buffer request up to the next multiple */
1422 new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1);
1423 avail = audit_expand(ab, new_len);
1428 ptr = skb_tail_pointer(skb);
1429 for (i=0; i<len; i++) {
1430 *ptr++ = hex[(buf[i] & 0xF0)>>4]; /* Upper nibble */
1431 *ptr++ = hex[buf[i] & 0x0F]; /* Lower nibble */
1434 skb_put(skb, len << 1); /* new string is twice the old string */
1438 * Format a string of no more than slen characters into the audit buffer,
1439 * enclosed in quote marks.
1441 void audit_log_n_string(struct audit_buffer *ab, const char *string,
1446 struct sk_buff *skb;
1453 avail = skb_tailroom(skb);
1454 new_len = slen + 3; /* enclosing quotes + null terminator */
1455 if (new_len > avail) {
1456 avail = audit_expand(ab, new_len);
1460 ptr = skb_tail_pointer(skb);
1462 memcpy(ptr, string, slen);
1466 skb_put(skb, slen + 2); /* don't include null terminator */
1470 * audit_string_contains_control - does a string need to be logged in hex
1471 * @string: string to be checked
1472 * @len: max length of the string to check
1474 int audit_string_contains_control(const char *string, size_t len)
1476 const unsigned char *p;
1477 for (p = string; p < (const unsigned char *)string + len; p++) {
1478 if (*p == '"' || *p < 0x21 || *p > 0x7e)
1485 * audit_log_n_untrustedstring - log a string that may contain random characters
1487 * @len: length of string (not including trailing null)
1488 * @string: string to be logged
1490 * This code will escape a string that is passed to it if the string
1491 * contains a control character, unprintable character, double quote mark,
1492 * or a space. Unescaped strings will start and end with a double quote mark.
1493 * Strings that are escaped are printed in hex (2 digits per char).
1495 * The caller specifies the number of characters in the string to log, which may
1496 * or may not be the entire string.
1498 void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string,
1501 if (audit_string_contains_control(string, len))
1502 audit_log_n_hex(ab, string, len);
1504 audit_log_n_string(ab, string, len);
1508 * audit_log_untrustedstring - log a string that may contain random characters
1510 * @string: string to be logged
1512 * Same as audit_log_n_untrustedstring(), except that strlen is used to
1513 * determine string length.
1515 void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
1517 audit_log_n_untrustedstring(ab, string, strlen(string));
1520 /* This is a helper-function to print the escaped d_path */
1521 void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
1522 const struct path *path)
1527 audit_log_format(ab, "%s", prefix);
1529 /* We will allow 11 spaces for ' (deleted)' to be appended */
1530 pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
1532 audit_log_string(ab, "<no_memory>");
1535 p = d_path(path, pathname, PATH_MAX+11);
1536 if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
1537 /* FIXME: can we save some information here? */
1538 audit_log_string(ab, "<too_long>");
1540 audit_log_untrustedstring(ab, p);
1544 void audit_log_session_info(struct audit_buffer *ab)
1546 u32 sessionid = audit_get_sessionid(current);
1547 uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current));
1549 audit_log_format(ab, " auid=%u ses=%u", auid, sessionid);
1552 void audit_log_key(struct audit_buffer *ab, char *key)
1554 audit_log_format(ab, " key=");
1556 audit_log_untrustedstring(ab, key);
1558 audit_log_format(ab, "(null)");
1561 void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
1565 audit_log_format(ab, " %s=", prefix);
1566 CAP_FOR_EACH_U32(i) {
1567 audit_log_format(ab, "%08x",
1568 cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
1572 void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1574 kernel_cap_t *perm = &name->fcap.permitted;
1575 kernel_cap_t *inh = &name->fcap.inheritable;
1578 if (!cap_isclear(*perm)) {
1579 audit_log_cap(ab, "cap_fp", perm);
1582 if (!cap_isclear(*inh)) {
1583 audit_log_cap(ab, "cap_fi", inh);
1588 audit_log_format(ab, " cap_fe=%d cap_fver=%x",
1589 name->fcap.fE, name->fcap_ver);
1592 static inline int audit_copy_fcaps(struct audit_names *name,
1593 const struct dentry *dentry)
1595 struct cpu_vfs_cap_data caps;
1601 rc = get_vfs_caps_from_disk(dentry, &caps);
1605 name->fcap.permitted = caps.permitted;
1606 name->fcap.inheritable = caps.inheritable;
1607 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
1608 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >>
1609 VFS_CAP_REVISION_SHIFT;
1614 /* Copy inode data into an audit_names. */
1615 void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
1616 const struct inode *inode)
1618 name->ino = inode->i_ino;
1619 name->dev = inode->i_sb->s_dev;
1620 name->mode = inode->i_mode;
1621 name->uid = inode->i_uid;
1622 name->gid = inode->i_gid;
1623 name->rdev = inode->i_rdev;
1624 security_inode_getsecid(inode, &name->osid);
1625 audit_copy_fcaps(name, dentry);
1629 * audit_log_name - produce AUDIT_PATH record from struct audit_names
1630 * @context: audit_context for the task
1631 * @n: audit_names structure with reportable details
1632 * @path: optional path to report instead of audit_names->name
1633 * @record_num: record number to report when handling a list of names
1634 * @call_panic: optional pointer to int that will be updated if secid fails
1636 void audit_log_name(struct audit_context *context, struct audit_names *n,
1637 struct path *path, int record_num, int *call_panic)
1639 struct audit_buffer *ab;
1640 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1644 audit_log_format(ab, "item=%d", record_num);
1647 audit_log_d_path(ab, " name=", path);
1649 switch (n->name_len) {
1650 case AUDIT_NAME_FULL:
1651 /* log the full path */
1652 audit_log_format(ab, " name=");
1653 audit_log_untrustedstring(ab, n->name->name);
1656 /* name was specified as a relative path and the
1657 * directory component is the cwd */
1658 audit_log_d_path(ab, " name=", &context->pwd);
1661 /* log the name's directory component */
1662 audit_log_format(ab, " name=");
1663 audit_log_n_untrustedstring(ab, n->name->name,
1667 audit_log_format(ab, " name=(null)");
1669 if (n->ino != (unsigned long)-1) {
1670 audit_log_format(ab, " inode=%lu"
1671 " dev=%02x:%02x mode=%#ho"
1672 " ouid=%u ogid=%u rdev=%02x:%02x",
1677 from_kuid(&init_user_ns, n->uid),
1678 from_kgid(&init_user_ns, n->gid),
1685 if (security_secid_to_secctx(
1686 n->osid, &ctx, &len)) {
1687 audit_log_format(ab, " osid=%u", n->osid);
1691 audit_log_format(ab, " obj=%s", ctx);
1692 security_release_secctx(ctx, len);
1696 /* log the audit_names record type */
1697 audit_log_format(ab, " nametype=");
1699 case AUDIT_TYPE_NORMAL:
1700 audit_log_format(ab, "NORMAL");
1702 case AUDIT_TYPE_PARENT:
1703 audit_log_format(ab, "PARENT");
1705 case AUDIT_TYPE_CHILD_DELETE:
1706 audit_log_format(ab, "DELETE");
1708 case AUDIT_TYPE_CHILD_CREATE:
1709 audit_log_format(ab, "CREATE");
1712 audit_log_format(ab, "UNKNOWN");
1716 audit_log_fcaps(ab, n);
1720 int audit_log_task_context(struct audit_buffer *ab)
1727 security_task_getsecid(current, &sid);
1731 error = security_secid_to_secctx(sid, &ctx, &len);
1733 if (error != -EINVAL)
1738 audit_log_format(ab, " subj=%s", ctx);
1739 security_release_secctx(ctx, len);
1743 audit_panic("error in audit_log_task_context");
1746 EXPORT_SYMBOL(audit_log_task_context);
1748 void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
1750 const struct cred *cred;
1751 char name[sizeof(tsk->comm)];
1752 struct mm_struct *mm = tsk->mm;
1758 /* tsk == current */
1759 cred = current_cred();
1761 spin_lock_irq(&tsk->sighand->siglock);
1762 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1763 tty = tsk->signal->tty->name;
1766 spin_unlock_irq(&tsk->sighand->siglock);
1768 audit_log_format(ab,
1769 " ppid=%ld pid=%d auid=%u uid=%u gid=%u"
1770 " euid=%u suid=%u fsuid=%u"
1771 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1774 from_kuid(&init_user_ns, audit_get_loginuid(tsk)),
1775 from_kuid(&init_user_ns, cred->uid),
1776 from_kgid(&init_user_ns, cred->gid),
1777 from_kuid(&init_user_ns, cred->euid),
1778 from_kuid(&init_user_ns, cred->suid),
1779 from_kuid(&init_user_ns, cred->fsuid),
1780 from_kgid(&init_user_ns, cred->egid),
1781 from_kgid(&init_user_ns, cred->sgid),
1782 from_kgid(&init_user_ns, cred->fsgid),
1783 tty, audit_get_sessionid(tsk));
1785 get_task_comm(name, tsk);
1786 audit_log_format(ab, " comm=");
1787 audit_log_untrustedstring(ab, name);
1790 down_read(&mm->mmap_sem);
1792 audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
1793 up_read(&mm->mmap_sem);
1795 audit_log_task_context(ab);
1797 EXPORT_SYMBOL(audit_log_task_info);
1800 * audit_log_link_denied - report a link restriction denial
1801 * @operation: specific link opreation
1802 * @link: the path that triggered the restriction
1804 void audit_log_link_denied(const char *operation, struct path *link)
1806 struct audit_buffer *ab;
1807 struct audit_names *name;
1809 name = kzalloc(sizeof(*name), GFP_NOFS);
1813 /* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */
1814 ab = audit_log_start(current->audit_context, GFP_KERNEL,
1818 audit_log_format(ab, "op=%s", operation);
1819 audit_log_task_info(ab, current);
1820 audit_log_format(ab, " res=0");
1823 /* Generate AUDIT_PATH record with object. */
1824 name->type = AUDIT_TYPE_NORMAL;
1825 audit_copy_inode(name, link->dentry, link->dentry->d_inode);
1826 audit_log_name(current->audit_context, name, link, 0, NULL);
1832 * audit_log_end - end one audit record
1833 * @ab: the audit_buffer
1835 * The netlink_* functions cannot be called inside an irq context, so
1836 * the audit buffer is placed on a queue and a tasklet is scheduled to
1837 * remove them from the queue outside the irq context. May be called in
1840 void audit_log_end(struct audit_buffer *ab)
1844 if (!audit_rate_check()) {
1845 audit_log_lost("rate limit exceeded");
1847 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
1848 nlh->nlmsg_len = ab->skb->len - NLMSG_HDRLEN;
1851 skb_queue_tail(&audit_skb_queue, ab->skb);
1852 wake_up_interruptible(&kauditd_wait);
1854 audit_printk_skb(ab->skb);
1858 audit_buffer_free(ab);
1862 * audit_log - Log an audit record
1863 * @ctx: audit context
1864 * @gfp_mask: type of allocation
1865 * @type: audit message type
1866 * @fmt: format string to use
1867 * @...: variable parameters matching the format string
1869 * This is a convenience function that calls audit_log_start,
1870 * audit_log_vformat, and audit_log_end. It may be called
1873 void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
1874 const char *fmt, ...)
1876 struct audit_buffer *ab;
1879 ab = audit_log_start(ctx, gfp_mask, type);
1881 va_start(args, fmt);
1882 audit_log_vformat(ab, fmt, args);
1888 #ifdef CONFIG_SECURITY
1890 * audit_log_secctx - Converts and logs SELinux context
1892 * @secid: security number
1894 * This is a helper function that calls security_secid_to_secctx to convert
1895 * secid to secctx and then adds the (converted) SELinux context to the audit
1896 * log by calling audit_log_format, thus also preventing leak of internal secid
1897 * to userspace. If secid cannot be converted audit_panic is called.
1899 void audit_log_secctx(struct audit_buffer *ab, u32 secid)
1904 if (security_secid_to_secctx(secid, &secctx, &len)) {
1905 audit_panic("Cannot convert secid to context");
1907 audit_log_format(ab, " obj=%s", secctx);
1908 security_release_secctx(secctx, len);
1911 EXPORT_SYMBOL(audit_log_secctx);
1914 EXPORT_SYMBOL(audit_log_start);
1915 EXPORT_SYMBOL(audit_log_end);
1916 EXPORT_SYMBOL(audit_log_format);
1917 EXPORT_SYMBOL(audit_log);