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 = AUDIT_BACKLOG_WAIT_TIME;
111 static u32 audit_backlog_wait_overflow = 0;
113 /* The identity of the user shutting down the audit system. */
114 kuid_t audit_sig_uid = INVALID_UID;
115 pid_t audit_sig_pid = -1;
116 u32 audit_sig_sid = 0;
118 /* Records can be lost in several ways:
119 0) [suppressed in audit_alloc]
120 1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
121 2) out of memory in audit_log_move [alloc_skb]
122 3) suppressed due to audit_rate_limit
123 4) suppressed due to audit_backlog_limit
125 static atomic_t audit_lost = ATOMIC_INIT(0);
127 /* The netlink socket. */
128 static struct sock *audit_sock;
131 /* Hash for inode-based rules */
132 struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
134 /* The audit_freelist is a list of pre-allocated audit buffers (if more
135 * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
136 * being placed on the freelist). */
137 static DEFINE_SPINLOCK(audit_freelist_lock);
138 static int audit_freelist_count;
139 static LIST_HEAD(audit_freelist);
141 static struct sk_buff_head audit_skb_queue;
142 /* queue of skbs to send to auditd when/if it comes back */
143 static struct sk_buff_head audit_skb_hold_queue;
144 static struct task_struct *kauditd_task;
145 static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
146 static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
148 static struct audit_features af = {.vers = AUDIT_FEATURE_VERSION,
153 static char *audit_feature_names[2] = {
154 "only_unset_loginuid",
155 "loginuid_immutable",
159 /* Serialize requests from userspace. */
160 DEFINE_MUTEX(audit_cmd_mutex);
162 /* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
163 * audit records. Since printk uses a 1024 byte buffer, this buffer
164 * should be at least that large. */
165 #define AUDIT_BUFSIZ 1024
167 /* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the
168 * audit_freelist. Doing so eliminates many kmalloc/kfree calls. */
169 #define AUDIT_MAXFREE (2*NR_CPUS)
171 /* The audit_buffer is used when formatting an audit record. The caller
172 * locks briefly to get the record off the freelist or to allocate the
173 * buffer, and locks briefly to send the buffer to the netlink layer or
174 * to place it on a transmit queue. Multiple audit_buffers can be in
175 * use simultaneously. */
176 struct audit_buffer {
177 struct list_head list;
178 struct sk_buff *skb; /* formatted skb ready to send */
179 struct audit_context *ctx; /* NULL or associated context */
189 static void audit_set_portid(struct audit_buffer *ab, __u32 portid)
192 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
193 nlh->nlmsg_pid = portid;
197 void audit_panic(const char *message)
199 switch (audit_failure) {
200 case AUDIT_FAIL_SILENT:
202 case AUDIT_FAIL_PRINTK:
203 if (printk_ratelimit())
204 pr_err("%s\n", message);
206 case AUDIT_FAIL_PANIC:
207 /* test audit_pid since printk is always losey, why bother? */
209 panic("audit: %s\n", message);
214 static inline int audit_rate_check(void)
216 static unsigned long last_check = 0;
217 static int messages = 0;
218 static DEFINE_SPINLOCK(lock);
221 unsigned long elapsed;
224 if (!audit_rate_limit) return 1;
226 spin_lock_irqsave(&lock, flags);
227 if (++messages < audit_rate_limit) {
231 elapsed = now - last_check;
238 spin_unlock_irqrestore(&lock, flags);
244 * audit_log_lost - conditionally log lost audit message event
245 * @message: the message stating reason for lost audit message
247 * Emit at least 1 message per second, even if audit_rate_check is
249 * Always increment the lost messages counter.
251 void audit_log_lost(const char *message)
253 static unsigned long last_msg = 0;
254 static DEFINE_SPINLOCK(lock);
259 atomic_inc(&audit_lost);
261 print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit);
264 spin_lock_irqsave(&lock, flags);
266 if (now - last_msg > HZ) {
270 spin_unlock_irqrestore(&lock, flags);
274 if (printk_ratelimit())
275 pr_warn("audit_lost=%u audit_rate_limit=%u audit_backlog_limit=%u\n",
276 atomic_read(&audit_lost),
278 audit_backlog_limit);
279 audit_panic(message);
283 static int audit_log_config_change(char *function_name, u32 new, u32 old,
286 struct audit_buffer *ab;
289 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
292 audit_log_format(ab, "%s=%u old=%u", 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, u32 *to_change, u32 new)
304 int allow_changes, rc = 0;
305 u32 old = *to_change;
307 /* check if we are locked */
308 if (audit_enabled == AUDIT_LOCKED)
313 if (audit_enabled != AUDIT_OFF) {
314 rc = audit_log_config_change(function_name, new, old, allow_changes);
319 /* If we are allowed, make the change */
320 if (allow_changes == 1)
322 /* Not allowed, update reason */
328 static int audit_set_rate_limit(u32 limit)
330 return audit_do_config_change("audit_rate_limit", &audit_rate_limit, limit);
333 static int audit_set_backlog_limit(u32 limit)
335 return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, limit);
338 static int audit_set_backlog_wait_time(u32 timeout)
340 return audit_do_config_change("audit_backlog_wait_time",
341 &audit_backlog_wait_time, timeout);
344 static int audit_set_enabled(u32 state)
347 if (state < AUDIT_OFF || state > AUDIT_LOCKED)
350 rc = audit_do_config_change("audit_enabled", &audit_enabled, state);
352 audit_ever_enabled |= !!state;
357 static int audit_set_failure(u32 state)
359 if (state != AUDIT_FAIL_SILENT
360 && state != AUDIT_FAIL_PRINTK
361 && state != AUDIT_FAIL_PANIC)
364 return audit_do_config_change("audit_failure", &audit_failure, state);
368 * Queue skbs to be sent to auditd when/if it comes back. These skbs should
369 * already have been sent via prink/syslog and so if these messages are dropped
370 * it is not a huge concern since we already passed the audit_log_lost()
371 * notification and stuff. This is just nice to get audit messages during
372 * boot before auditd is running or messages generated while auditd is stopped.
373 * This only holds messages is audit_default is set, aka booting with audit=1
374 * or building your kernel that way.
376 static void audit_hold_skb(struct sk_buff *skb)
379 (!audit_backlog_limit ||
380 skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit))
381 skb_queue_tail(&audit_skb_hold_queue, skb);
387 * For one reason or another this nlh isn't getting delivered to the userspace
388 * audit daemon, just send it to printk.
390 static void audit_printk_skb(struct sk_buff *skb)
392 struct nlmsghdr *nlh = nlmsg_hdr(skb);
393 char *data = nlmsg_data(nlh);
395 if (nlh->nlmsg_type != AUDIT_EOE) {
396 if (printk_ratelimit())
397 pr_notice("type=%d %s\n", nlh->nlmsg_type, data);
399 audit_log_lost("printk limit exceeded");
405 static void kauditd_send_skb(struct sk_buff *skb)
408 /* take a reference in case we can't send it and we want to hold it */
410 err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0);
412 BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
414 pr_err("*NO* daemon at audit_pid=%d\n", audit_pid);
415 audit_log_lost("auditd disappeared");
419 /* we might get lucky and get this in the next auditd */
422 /* drop the extra reference if sent ok */
427 * flush_hold_queue - empty the hold queue if auditd appears
429 * If auditd just started, drain the queue of messages already
430 * sent to syslog/printk. Remember loss here is ok. We already
431 * called audit_log_lost() if it didn't go out normally. so the
432 * race between the skb_dequeue and the next check for audit_pid
435 * If you ever find kauditd to be too slow we can get a perf win
436 * by doing our own locking and keeping better track if there
437 * are messages in this queue. I don't see the need now, but
438 * in 5 years when I want to play with this again I'll see this
439 * note and still have no friggin idea what i'm thinking today.
441 static void flush_hold_queue(void)
445 if (!audit_default || !audit_pid)
448 skb = skb_dequeue(&audit_skb_hold_queue);
452 while (skb && audit_pid) {
453 kauditd_send_skb(skb);
454 skb = skb_dequeue(&audit_skb_hold_queue);
458 * if auditd just disappeared but we
459 * dequeued an skb we need to drop ref
465 static int kauditd_thread(void *dummy)
468 while (!kthread_should_stop()) {
470 DECLARE_WAITQUEUE(wait, current);
474 skb = skb_dequeue(&audit_skb_queue);
477 if (skb_queue_len(&audit_skb_queue) <= audit_backlog_limit)
478 wake_up(&audit_backlog_wait);
480 kauditd_send_skb(skb);
482 audit_printk_skb(skb);
485 set_current_state(TASK_INTERRUPTIBLE);
486 add_wait_queue(&kauditd_wait, &wait);
488 if (!skb_queue_len(&audit_skb_queue)) {
493 __set_current_state(TASK_RUNNING);
494 remove_wait_queue(&kauditd_wait, &wait);
499 int audit_send_list(void *_dest)
501 struct audit_netlink_list *dest = _dest;
503 struct net *net = dest->net;
504 struct audit_net *aunet = net_generic(net, audit_net_id);
506 /* wait for parent to finish and send an ACK */
507 mutex_lock(&audit_cmd_mutex);
508 mutex_unlock(&audit_cmd_mutex);
510 while ((skb = __skb_dequeue(&dest->q)) != NULL)
511 netlink_unicast(aunet->nlsk, skb, dest->portid, 0);
519 struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, int done,
520 int multi, const void *payload, int size)
523 struct nlmsghdr *nlh;
525 int flags = multi ? NLM_F_MULTI : 0;
526 int t = done ? NLMSG_DONE : type;
528 skb = nlmsg_new(size, GFP_KERNEL);
532 nlh = nlmsg_put(skb, portid, seq, t, size, flags);
535 data = nlmsg_data(nlh);
536 memcpy(data, payload, size);
544 static int audit_send_reply_thread(void *arg)
546 struct audit_reply *reply = (struct audit_reply *)arg;
547 struct net *net = reply->net;
548 struct audit_net *aunet = net_generic(net, audit_net_id);
550 mutex_lock(&audit_cmd_mutex);
551 mutex_unlock(&audit_cmd_mutex);
553 /* Ignore failure. It'll only happen if the sender goes away,
554 because our timeout is set to infinite. */
555 netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0);
561 * audit_send_reply - send an audit reply message via netlink
562 * @request_skb: skb of request we are replying to (used to target the reply)
563 * @seq: sequence number
564 * @type: audit message type
565 * @done: done (last) flag
566 * @multi: multi-part message flag
567 * @payload: payload data
568 * @size: payload size
570 * Allocates an skb, builds the netlink message, and sends it to the port id.
571 * No failure notifications.
573 static void audit_send_reply(struct sk_buff *request_skb, int seq, int type, int done,
574 int multi, const void *payload, int size)
576 u32 portid = NETLINK_CB(request_skb).portid;
577 struct net *net = sock_net(NETLINK_CB(request_skb).sk);
579 struct task_struct *tsk;
580 struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
586 skb = audit_make_reply(portid, seq, type, done, multi, payload, size);
590 reply->net = get_net(net);
591 reply->portid = portid;
594 tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
603 * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
606 static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
610 /* Only support initial user namespace for now. */
612 * We return ECONNREFUSED because it tricks userspace into thinking
613 * that audit was not configured into the kernel. Lots of users
614 * configure their PAM stack (because that's what the distro does)
615 * to reject login if unable to send messages to audit. If we return
616 * ECONNREFUSED the PAM stack thinks the kernel does not have audit
617 * configured in and will let login proceed. If we return EPERM
618 * userspace will reject all logins. This should be removed when we
619 * support non init namespaces!!
621 if (current_user_ns() != &init_user_ns)
622 return -ECONNREFUSED;
631 case AUDIT_GET_FEATURE:
632 case AUDIT_SET_FEATURE:
633 case AUDIT_LIST_RULES:
636 case AUDIT_SIGNAL_INFO:
640 case AUDIT_MAKE_EQUIV:
641 /* Only support auditd and auditctl in initial pid namespace
643 if ((task_active_pid_ns(current) != &init_pid_ns))
646 if (!netlink_capable(skb, CAP_AUDIT_CONTROL))
650 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
651 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
652 if (!netlink_capable(skb, CAP_AUDIT_WRITE))
655 default: /* bad msg */
662 static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
665 uid_t uid = from_kuid(&init_user_ns, current_uid());
666 pid_t pid = task_tgid_nr(current);
668 if (!audit_enabled && msg_type != AUDIT_USER_AVC) {
673 *ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
676 audit_log_format(*ab, "pid=%d uid=%u", pid, uid);
677 audit_log_session_info(*ab);
678 audit_log_task_context(*ab);
683 int is_audit_feature_set(int i)
685 return af.features & AUDIT_FEATURE_TO_MASK(i);
689 static int audit_get_feature(struct sk_buff *skb)
693 seq = nlmsg_hdr(skb)->nlmsg_seq;
695 audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &af, sizeof(af));
700 static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature,
701 u32 old_lock, u32 new_lock, int res)
703 struct audit_buffer *ab;
705 if (audit_enabled == AUDIT_OFF)
708 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE);
709 audit_log_task_info(ab, current);
710 audit_log_format(ab, "feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d",
711 audit_feature_names[which], !!old_feature, !!new_feature,
712 !!old_lock, !!new_lock, res);
716 static int audit_set_feature(struct sk_buff *skb)
718 struct audit_features *uaf;
721 BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > sizeof(audit_feature_names)/sizeof(audit_feature_names[0]));
722 uaf = nlmsg_data(nlmsg_hdr(skb));
724 /* if there is ever a version 2 we should handle that here */
726 for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
727 u32 feature = AUDIT_FEATURE_TO_MASK(i);
728 u32 old_feature, new_feature, old_lock, new_lock;
730 /* if we are not changing this feature, move along */
731 if (!(feature & uaf->mask))
734 old_feature = af.features & feature;
735 new_feature = uaf->features & feature;
736 new_lock = (uaf->lock | af.lock) & feature;
737 old_lock = af.lock & feature;
739 /* are we changing a locked feature? */
740 if (old_lock && (new_feature != old_feature)) {
741 audit_log_feature_change(i, old_feature, new_feature,
742 old_lock, new_lock, 0);
746 /* nothing invalid, do the changes */
747 for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
748 u32 feature = AUDIT_FEATURE_TO_MASK(i);
749 u32 old_feature, new_feature, old_lock, new_lock;
751 /* if we are not changing this feature, move along */
752 if (!(feature & uaf->mask))
755 old_feature = af.features & feature;
756 new_feature = uaf->features & feature;
757 old_lock = af.lock & feature;
758 new_lock = (uaf->lock | af.lock) & feature;
760 if (new_feature != old_feature)
761 audit_log_feature_change(i, old_feature, new_feature,
762 old_lock, new_lock, 1);
765 af.features |= feature;
767 af.features &= ~feature;
774 static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
779 struct audit_buffer *ab;
780 u16 msg_type = nlh->nlmsg_type;
781 struct audit_sig_info *sig_data;
785 err = audit_netlink_ok(skb, msg_type);
789 /* As soon as there's any sign of userspace auditd,
790 * start kauditd to talk to it */
792 kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
793 if (IS_ERR(kauditd_task)) {
794 err = PTR_ERR(kauditd_task);
799 seq = nlh->nlmsg_seq;
800 data = nlmsg_data(nlh);
804 struct audit_status s;
805 memset(&s, 0, sizeof(s));
806 s.enabled = audit_enabled;
807 s.failure = audit_failure;
809 s.rate_limit = audit_rate_limit;
810 s.backlog_limit = audit_backlog_limit;
811 s.lost = atomic_read(&audit_lost);
812 s.backlog = skb_queue_len(&audit_skb_queue);
813 s.version = AUDIT_VERSION_LATEST;
814 s.backlog_wait_time = audit_backlog_wait_time;
815 audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &s, sizeof(s));
819 struct audit_status s;
820 memset(&s, 0, sizeof(s));
821 /* guard against past and future API changes */
822 memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
823 if (s.mask & AUDIT_STATUS_ENABLED) {
824 err = audit_set_enabled(s.enabled);
828 if (s.mask & AUDIT_STATUS_FAILURE) {
829 err = audit_set_failure(s.failure);
833 if (s.mask & AUDIT_STATUS_PID) {
836 if ((!new_pid) && (task_tgid_vnr(current) != audit_pid))
838 if (audit_enabled != AUDIT_OFF)
839 audit_log_config_change("audit_pid", new_pid, audit_pid, 1);
841 audit_nlk_portid = NETLINK_CB(skb).portid;
842 audit_sock = skb->sk;
844 if (s.mask & AUDIT_STATUS_RATE_LIMIT) {
845 err = audit_set_rate_limit(s.rate_limit);
849 if (s.mask & AUDIT_STATUS_BACKLOG_LIMIT) {
850 err = audit_set_backlog_limit(s.backlog_limit);
854 if (s.mask & AUDIT_STATUS_BACKLOG_WAIT_TIME) {
855 if (sizeof(s) > (size_t)nlh->nlmsg_len)
857 if (s.backlog_wait_time < 0 ||
858 s.backlog_wait_time > 10*AUDIT_BACKLOG_WAIT_TIME)
860 err = audit_set_backlog_wait_time(s.backlog_wait_time);
866 case AUDIT_GET_FEATURE:
867 err = audit_get_feature(skb);
871 case AUDIT_SET_FEATURE:
872 err = audit_set_feature(skb);
877 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
878 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
879 if (!audit_enabled && msg_type != AUDIT_USER_AVC)
882 err = audit_filter_user(msg_type);
883 if (err == 1) { /* match or error */
885 if (msg_type == AUDIT_USER_TTY) {
886 err = tty_audit_push_current();
890 mutex_unlock(&audit_cmd_mutex);
891 audit_log_common_recv_msg(&ab, msg_type);
892 if (msg_type != AUDIT_USER_TTY)
893 audit_log_format(ab, " msg='%.*s'",
894 AUDIT_MESSAGE_TEXT_MAX,
899 audit_log_format(ab, " data=");
900 size = nlmsg_len(nlh);
902 ((unsigned char *)data)[size - 1] == '\0')
904 audit_log_n_untrustedstring(ab, data, size);
906 audit_set_portid(ab, NETLINK_CB(skb).portid);
908 mutex_lock(&audit_cmd_mutex);
913 if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
915 if (audit_enabled == AUDIT_LOCKED) {
916 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
917 audit_log_format(ab, " audit_enabled=%d res=0", audit_enabled);
921 err = audit_rule_change(msg_type, NETLINK_CB(skb).portid,
922 seq, data, nlmsg_len(nlh));
924 case AUDIT_LIST_RULES:
925 err = audit_list_rules_send(skb, seq);
929 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
930 audit_log_format(ab, " op=trim res=1");
933 case AUDIT_MAKE_EQUIV: {
936 size_t msglen = nlmsg_len(nlh);
940 if (msglen < 2 * sizeof(u32))
942 memcpy(sizes, bufp, 2 * sizeof(u32));
943 bufp += 2 * sizeof(u32);
944 msglen -= 2 * sizeof(u32);
945 old = audit_unpack_string(&bufp, &msglen, sizes[0]);
950 new = audit_unpack_string(&bufp, &msglen, sizes[1]);
956 /* OK, here comes... */
957 err = audit_tag_tree(old, new);
959 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
961 audit_log_format(ab, " op=make_equiv old=");
962 audit_log_untrustedstring(ab, old);
963 audit_log_format(ab, " new=");
964 audit_log_untrustedstring(ab, new);
965 audit_log_format(ab, " res=%d", !err);
971 case AUDIT_SIGNAL_INFO:
974 err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
978 sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
981 security_release_secctx(ctx, len);
984 sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
985 sig_data->pid = audit_sig_pid;
987 memcpy(sig_data->ctx, ctx, len);
988 security_release_secctx(ctx, len);
990 audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
991 sig_data, sizeof(*sig_data) + len);
994 case AUDIT_TTY_GET: {
995 struct audit_tty_status s;
996 struct task_struct *tsk = current;
998 spin_lock(&tsk->sighand->siglock);
999 s.enabled = tsk->signal->audit_tty;
1000 s.log_passwd = tsk->signal->audit_tty_log_passwd;
1001 spin_unlock(&tsk->sighand->siglock);
1003 audit_send_reply(skb, seq, AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
1006 case AUDIT_TTY_SET: {
1007 struct audit_tty_status s, old;
1008 struct task_struct *tsk = current;
1009 struct audit_buffer *ab;
1011 memset(&s, 0, sizeof(s));
1012 /* guard against past and future API changes */
1013 memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
1014 /* check if new data is valid */
1015 if ((s.enabled != 0 && s.enabled != 1) ||
1016 (s.log_passwd != 0 && s.log_passwd != 1))
1019 spin_lock(&tsk->sighand->siglock);
1020 old.enabled = tsk->signal->audit_tty;
1021 old.log_passwd = tsk->signal->audit_tty_log_passwd;
1023 tsk->signal->audit_tty = s.enabled;
1024 tsk->signal->audit_tty_log_passwd = s.log_passwd;
1026 spin_unlock(&tsk->sighand->siglock);
1028 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
1029 audit_log_format(ab, " op=tty_set old-enabled=%d new-enabled=%d"
1030 " old-log_passwd=%d new-log_passwd=%d res=%d",
1031 old.enabled, s.enabled, old.log_passwd,
1032 s.log_passwd, !err);
1041 return err < 0 ? err : 0;
1045 * Get message from skb. Each message is processed by audit_receive_msg.
1046 * Malformed skbs with wrong length are discarded silently.
1048 static void audit_receive_skb(struct sk_buff *skb)
1050 struct nlmsghdr *nlh;
1052 * len MUST be signed for nlmsg_next to be able to dec it below 0
1053 * if the nlmsg_len was not aligned
1058 nlh = nlmsg_hdr(skb);
1061 while (nlmsg_ok(nlh, len)) {
1062 err = audit_receive_msg(skb, nlh);
1063 /* if err or if this message says it wants a response */
1064 if (err || (nlh->nlmsg_flags & NLM_F_ACK))
1065 netlink_ack(skb, nlh, err);
1067 nlh = nlmsg_next(nlh, &len);
1071 /* Receive messages from netlink socket. */
1072 static void audit_receive(struct sk_buff *skb)
1074 mutex_lock(&audit_cmd_mutex);
1075 audit_receive_skb(skb);
1076 mutex_unlock(&audit_cmd_mutex);
1079 static int __net_init audit_net_init(struct net *net)
1081 struct netlink_kernel_cfg cfg = {
1082 .input = audit_receive,
1085 struct audit_net *aunet = net_generic(net, audit_net_id);
1087 aunet->nlsk = netlink_kernel_create(net, NETLINK_AUDIT, &cfg);
1088 if (aunet->nlsk == NULL) {
1089 audit_panic("cannot initialize netlink socket in namespace");
1092 aunet->nlsk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
1096 static void __net_exit audit_net_exit(struct net *net)
1098 struct audit_net *aunet = net_generic(net, audit_net_id);
1099 struct sock *sock = aunet->nlsk;
1100 if (sock == audit_sock) {
1105 RCU_INIT_POINTER(aunet->nlsk, NULL);
1107 netlink_kernel_release(sock);
1110 static struct pernet_operations audit_net_ops __net_initdata = {
1111 .init = audit_net_init,
1112 .exit = audit_net_exit,
1113 .id = &audit_net_id,
1114 .size = sizeof(struct audit_net),
1117 /* Initialize audit support at boot time. */
1118 static int __init audit_init(void)
1122 if (audit_initialized == AUDIT_DISABLED)
1125 pr_info("initializing netlink subsys (%s)\n",
1126 audit_default ? "enabled" : "disabled");
1127 register_pernet_subsys(&audit_net_ops);
1129 skb_queue_head_init(&audit_skb_queue);
1130 skb_queue_head_init(&audit_skb_hold_queue);
1131 audit_initialized = AUDIT_INITIALIZED;
1132 audit_enabled = audit_default;
1133 audit_ever_enabled |= !!audit_default;
1135 audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
1137 for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
1138 INIT_LIST_HEAD(&audit_inode_hash[i]);
1142 __initcall(audit_init);
1144 /* Process kernel command-line parameter at boot time. audit=0 or audit=1. */
1145 static int __init audit_enable(char *str)
1147 audit_default = !!simple_strtol(str, NULL, 0);
1149 audit_initialized = AUDIT_DISABLED;
1151 pr_info("%s\n", audit_default ?
1152 "enabled (after initialization)" : "disabled (until reboot)");
1156 __setup("audit=", audit_enable);
1158 /* Process kernel command-line parameter at boot time.
1159 * audit_backlog_limit=<n> */
1160 static int __init audit_backlog_limit_set(char *str)
1162 u32 audit_backlog_limit_arg;
1164 pr_info("audit_backlog_limit: ");
1165 if (kstrtouint(str, 0, &audit_backlog_limit_arg)) {
1166 pr_cont("using default of %u, unable to parse %s\n",
1167 audit_backlog_limit, str);
1171 audit_backlog_limit = audit_backlog_limit_arg;
1172 pr_cont("%d\n", audit_backlog_limit);
1176 __setup("audit_backlog_limit=", audit_backlog_limit_set);
1178 static void audit_buffer_free(struct audit_buffer *ab)
1180 unsigned long flags;
1188 spin_lock_irqsave(&audit_freelist_lock, flags);
1189 if (audit_freelist_count > AUDIT_MAXFREE)
1192 audit_freelist_count++;
1193 list_add(&ab->list, &audit_freelist);
1195 spin_unlock_irqrestore(&audit_freelist_lock, flags);
1198 static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
1199 gfp_t gfp_mask, int type)
1201 unsigned long flags;
1202 struct audit_buffer *ab = NULL;
1203 struct nlmsghdr *nlh;
1205 spin_lock_irqsave(&audit_freelist_lock, flags);
1206 if (!list_empty(&audit_freelist)) {
1207 ab = list_entry(audit_freelist.next,
1208 struct audit_buffer, list);
1209 list_del(&ab->list);
1210 --audit_freelist_count;
1212 spin_unlock_irqrestore(&audit_freelist_lock, flags);
1215 ab = kmalloc(sizeof(*ab), gfp_mask);
1221 ab->gfp_mask = gfp_mask;
1223 ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask);
1227 nlh = nlmsg_put(ab->skb, 0, 0, type, 0, 0);
1237 audit_buffer_free(ab);
1242 * audit_serial - compute a serial number for the audit record
1244 * Compute a serial number for the audit record. Audit records are
1245 * written to user-space as soon as they are generated, so a complete
1246 * audit record may be written in several pieces. The timestamp of the
1247 * record and this serial number are used by the user-space tools to
1248 * determine which pieces belong to the same audit record. The
1249 * (timestamp,serial) tuple is unique for each syscall and is live from
1250 * syscall entry to syscall exit.
1252 * NOTE: Another possibility is to store the formatted records off the
1253 * audit context (for those records that have a context), and emit them
1254 * all at syscall exit. However, this could delay the reporting of
1255 * significant errors until syscall exit (or never, if the system
1258 unsigned int audit_serial(void)
1260 static DEFINE_SPINLOCK(serial_lock);
1261 static unsigned int serial = 0;
1263 unsigned long flags;
1266 spin_lock_irqsave(&serial_lock, flags);
1269 } while (unlikely(!ret));
1270 spin_unlock_irqrestore(&serial_lock, flags);
1275 static inline void audit_get_stamp(struct audit_context *ctx,
1276 struct timespec *t, unsigned int *serial)
1278 if (!ctx || !auditsc_get_stamp(ctx, t, serial)) {
1280 *serial = audit_serial();
1285 * Wait for auditd to drain the queue a little
1287 static long wait_for_auditd(long sleep_time)
1289 DECLARE_WAITQUEUE(wait, current);
1290 set_current_state(TASK_UNINTERRUPTIBLE);
1291 add_wait_queue_exclusive(&audit_backlog_wait, &wait);
1293 if (audit_backlog_limit &&
1294 skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
1295 sleep_time = schedule_timeout(sleep_time);
1297 __set_current_state(TASK_RUNNING);
1298 remove_wait_queue(&audit_backlog_wait, &wait);
1304 * audit_log_start - obtain an audit buffer
1305 * @ctx: audit_context (may be NULL)
1306 * @gfp_mask: type of allocation
1307 * @type: audit message type
1309 * Returns audit_buffer pointer on success or NULL on error.
1311 * Obtain an audit buffer. This routine does locking to obtain the
1312 * audit buffer, but then no locking is required for calls to
1313 * audit_log_*format. If the task (ctx) is a task that is currently in a
1314 * syscall, then the syscall is marked as auditable and an audit record
1315 * will be written at syscall exit. If there is no associated task, then
1316 * task context (ctx) should be NULL.
1318 struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
1321 struct audit_buffer *ab = NULL;
1323 unsigned int uninitialized_var(serial);
1324 int reserve = 5; /* Allow atomic callers to go up to five
1325 entries over the normal backlog limit */
1326 unsigned long timeout_start = jiffies;
1328 if (audit_initialized != AUDIT_INITIALIZED)
1331 if (unlikely(audit_filter_type(type)))
1334 if (gfp_mask & __GFP_WAIT) {
1335 if (audit_pid && audit_pid == current->pid)
1336 gfp_mask &= ~__GFP_WAIT;
1341 while (audit_backlog_limit
1342 && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
1343 if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) {
1346 sleep_time = timeout_start + audit_backlog_wait_time - jiffies;
1347 if (sleep_time > 0) {
1348 sleep_time = wait_for_auditd(sleep_time);
1353 if (audit_rate_check() && printk_ratelimit())
1354 pr_warn("audit_backlog=%d > audit_backlog_limit=%d\n",
1355 skb_queue_len(&audit_skb_queue),
1356 audit_backlog_limit);
1357 audit_log_lost("backlog limit exceeded");
1358 audit_backlog_wait_time = audit_backlog_wait_overflow;
1359 wake_up(&audit_backlog_wait);
1363 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
1365 ab = audit_buffer_alloc(ctx, gfp_mask, type);
1367 audit_log_lost("out of memory in audit_log_start");
1371 audit_get_stamp(ab->ctx, &t, &serial);
1373 audit_log_format(ab, "audit(%lu.%03lu:%u): ",
1374 t.tv_sec, t.tv_nsec/1000000, serial);
1379 * audit_expand - expand skb in the audit buffer
1381 * @extra: space to add at tail of the skb
1383 * Returns 0 (no space) on failed expansion, or available space if
1386 static inline int audit_expand(struct audit_buffer *ab, int extra)
1388 struct sk_buff *skb = ab->skb;
1389 int oldtail = skb_tailroom(skb);
1390 int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask);
1391 int newtail = skb_tailroom(skb);
1394 audit_log_lost("out of memory in audit_expand");
1398 skb->truesize += newtail - oldtail;
1403 * Format an audit message into the audit buffer. If there isn't enough
1404 * room in the audit buffer, more room will be allocated and vsnprint
1405 * will be called a second time. Currently, we assume that a printk
1406 * can't format message larger than 1024 bytes, so we don't either.
1408 static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
1412 struct sk_buff *skb;
1420 avail = skb_tailroom(skb);
1422 avail = audit_expand(ab, AUDIT_BUFSIZ);
1426 va_copy(args2, args);
1427 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args);
1429 /* The printk buffer is 1024 bytes long, so if we get
1430 * here and AUDIT_BUFSIZ is at least 1024, then we can
1431 * log everything that printk could have logged. */
1432 avail = audit_expand(ab,
1433 max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
1436 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2);
1447 * audit_log_format - format a message into the audit buffer.
1449 * @fmt: format string
1450 * @...: optional parameters matching @fmt string
1452 * All the work is done in audit_log_vformat.
1454 void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
1460 va_start(args, fmt);
1461 audit_log_vformat(ab, fmt, args);
1466 * audit_log_hex - convert a buffer to hex and append it to the audit skb
1467 * @ab: the audit_buffer
1468 * @buf: buffer to convert to hex
1469 * @len: length of @buf to be converted
1471 * No return value; failure to expand is silently ignored.
1473 * This function will take the passed buf and convert it into a string of
1474 * ascii hex digits. The new string is placed onto the skb.
1476 void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
1479 int i, avail, new_len;
1481 struct sk_buff *skb;
1488 avail = skb_tailroom(skb);
1490 if (new_len >= avail) {
1491 /* Round the buffer request up to the next multiple */
1492 new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1);
1493 avail = audit_expand(ab, new_len);
1498 ptr = skb_tail_pointer(skb);
1499 for (i = 0; i < len; i++)
1500 ptr = hex_byte_pack_upper(ptr, buf[i]);
1502 skb_put(skb, len << 1); /* new string is twice the old string */
1506 * Format a string of no more than slen characters into the audit buffer,
1507 * enclosed in quote marks.
1509 void audit_log_n_string(struct audit_buffer *ab, const char *string,
1514 struct sk_buff *skb;
1521 avail = skb_tailroom(skb);
1522 new_len = slen + 3; /* enclosing quotes + null terminator */
1523 if (new_len > avail) {
1524 avail = audit_expand(ab, new_len);
1528 ptr = skb_tail_pointer(skb);
1530 memcpy(ptr, string, slen);
1534 skb_put(skb, slen + 2); /* don't include null terminator */
1538 * audit_string_contains_control - does a string need to be logged in hex
1539 * @string: string to be checked
1540 * @len: max length of the string to check
1542 int audit_string_contains_control(const char *string, size_t len)
1544 const unsigned char *p;
1545 for (p = string; p < (const unsigned char *)string + len; p++) {
1546 if (*p == '"' || *p < 0x21 || *p > 0x7e)
1553 * audit_log_n_untrustedstring - log a string that may contain random characters
1555 * @len: length of string (not including trailing null)
1556 * @string: string to be logged
1558 * This code will escape a string that is passed to it if the string
1559 * contains a control character, unprintable character, double quote mark,
1560 * or a space. Unescaped strings will start and end with a double quote mark.
1561 * Strings that are escaped are printed in hex (2 digits per char).
1563 * The caller specifies the number of characters in the string to log, which may
1564 * or may not be the entire string.
1566 void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string,
1569 if (audit_string_contains_control(string, len))
1570 audit_log_n_hex(ab, string, len);
1572 audit_log_n_string(ab, string, len);
1576 * audit_log_untrustedstring - log a string that may contain random characters
1578 * @string: string to be logged
1580 * Same as audit_log_n_untrustedstring(), except that strlen is used to
1581 * determine string length.
1583 void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
1585 audit_log_n_untrustedstring(ab, string, strlen(string));
1588 /* This is a helper-function to print the escaped d_path */
1589 void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
1590 const struct path *path)
1595 audit_log_format(ab, "%s", prefix);
1597 /* We will allow 11 spaces for ' (deleted)' to be appended */
1598 pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
1600 audit_log_string(ab, "<no_memory>");
1603 p = d_path(path, pathname, PATH_MAX+11);
1604 if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
1605 /* FIXME: can we save some information here? */
1606 audit_log_string(ab, "<too_long>");
1608 audit_log_untrustedstring(ab, p);
1612 void audit_log_session_info(struct audit_buffer *ab)
1614 unsigned int sessionid = audit_get_sessionid(current);
1615 uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current));
1617 audit_log_format(ab, " auid=%u ses=%u", auid, sessionid);
1620 void audit_log_key(struct audit_buffer *ab, char *key)
1622 audit_log_format(ab, " key=");
1624 audit_log_untrustedstring(ab, key);
1626 audit_log_format(ab, "(null)");
1629 void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
1633 audit_log_format(ab, " %s=", prefix);
1634 CAP_FOR_EACH_U32(i) {
1635 audit_log_format(ab, "%08x",
1636 cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
1640 void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1642 kernel_cap_t *perm = &name->fcap.permitted;
1643 kernel_cap_t *inh = &name->fcap.inheritable;
1646 if (!cap_isclear(*perm)) {
1647 audit_log_cap(ab, "cap_fp", perm);
1650 if (!cap_isclear(*inh)) {
1651 audit_log_cap(ab, "cap_fi", inh);
1656 audit_log_format(ab, " cap_fe=%d cap_fver=%x",
1657 name->fcap.fE, name->fcap_ver);
1660 static inline int audit_copy_fcaps(struct audit_names *name,
1661 const struct dentry *dentry)
1663 struct cpu_vfs_cap_data caps;
1669 rc = get_vfs_caps_from_disk(dentry, &caps);
1673 name->fcap.permitted = caps.permitted;
1674 name->fcap.inheritable = caps.inheritable;
1675 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
1676 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >>
1677 VFS_CAP_REVISION_SHIFT;
1682 /* Copy inode data into an audit_names. */
1683 void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
1684 const struct inode *inode)
1686 name->ino = inode->i_ino;
1687 name->dev = inode->i_sb->s_dev;
1688 name->mode = inode->i_mode;
1689 name->uid = inode->i_uid;
1690 name->gid = inode->i_gid;
1691 name->rdev = inode->i_rdev;
1692 security_inode_getsecid(inode, &name->osid);
1693 audit_copy_fcaps(name, dentry);
1697 * audit_log_name - produce AUDIT_PATH record from struct audit_names
1698 * @context: audit_context for the task
1699 * @n: audit_names structure with reportable details
1700 * @path: optional path to report instead of audit_names->name
1701 * @record_num: record number to report when handling a list of names
1702 * @call_panic: optional pointer to int that will be updated if secid fails
1704 void audit_log_name(struct audit_context *context, struct audit_names *n,
1705 struct path *path, int record_num, int *call_panic)
1707 struct audit_buffer *ab;
1708 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1712 audit_log_format(ab, "item=%d", record_num);
1715 audit_log_d_path(ab, " name=", path);
1717 switch (n->name_len) {
1718 case AUDIT_NAME_FULL:
1719 /* log the full path */
1720 audit_log_format(ab, " name=");
1721 audit_log_untrustedstring(ab, n->name->name);
1724 /* name was specified as a relative path and the
1725 * directory component is the cwd */
1726 audit_log_d_path(ab, " name=", &context->pwd);
1729 /* log the name's directory component */
1730 audit_log_format(ab, " name=");
1731 audit_log_n_untrustedstring(ab, n->name->name,
1735 audit_log_format(ab, " name=(null)");
1737 if (n->ino != (unsigned long)-1) {
1738 audit_log_format(ab, " inode=%lu"
1739 " dev=%02x:%02x mode=%#ho"
1740 " ouid=%u ogid=%u rdev=%02x:%02x",
1745 from_kuid(&init_user_ns, n->uid),
1746 from_kgid(&init_user_ns, n->gid),
1753 if (security_secid_to_secctx(
1754 n->osid, &ctx, &len)) {
1755 audit_log_format(ab, " osid=%u", n->osid);
1759 audit_log_format(ab, " obj=%s", ctx);
1760 security_release_secctx(ctx, len);
1764 /* log the audit_names record type */
1765 audit_log_format(ab, " nametype=");
1767 case AUDIT_TYPE_NORMAL:
1768 audit_log_format(ab, "NORMAL");
1770 case AUDIT_TYPE_PARENT:
1771 audit_log_format(ab, "PARENT");
1773 case AUDIT_TYPE_CHILD_DELETE:
1774 audit_log_format(ab, "DELETE");
1776 case AUDIT_TYPE_CHILD_CREATE:
1777 audit_log_format(ab, "CREATE");
1780 audit_log_format(ab, "UNKNOWN");
1784 audit_log_fcaps(ab, n);
1788 int audit_log_task_context(struct audit_buffer *ab)
1795 security_task_getsecid(current, &sid);
1799 error = security_secid_to_secctx(sid, &ctx, &len);
1801 if (error != -EINVAL)
1806 audit_log_format(ab, " subj=%s", ctx);
1807 security_release_secctx(ctx, len);
1811 audit_panic("error in audit_log_task_context");
1814 EXPORT_SYMBOL(audit_log_task_context);
1816 void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
1818 const struct cred *cred;
1819 char name[sizeof(tsk->comm)];
1820 struct mm_struct *mm = tsk->mm;
1826 /* tsk == current */
1827 cred = current_cred();
1829 spin_lock_irq(&tsk->sighand->siglock);
1830 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1831 tty = tsk->signal->tty->name;
1834 spin_unlock_irq(&tsk->sighand->siglock);
1836 audit_log_format(ab,
1837 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1838 " euid=%u suid=%u fsuid=%u"
1839 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1842 from_kuid(&init_user_ns, audit_get_loginuid(tsk)),
1843 from_kuid(&init_user_ns, cred->uid),
1844 from_kgid(&init_user_ns, cred->gid),
1845 from_kuid(&init_user_ns, cred->euid),
1846 from_kuid(&init_user_ns, cred->suid),
1847 from_kuid(&init_user_ns, cred->fsuid),
1848 from_kgid(&init_user_ns, cred->egid),
1849 from_kgid(&init_user_ns, cred->sgid),
1850 from_kgid(&init_user_ns, cred->fsgid),
1851 tty, audit_get_sessionid(tsk));
1853 get_task_comm(name, tsk);
1854 audit_log_format(ab, " comm=");
1855 audit_log_untrustedstring(ab, name);
1858 down_read(&mm->mmap_sem);
1860 audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
1861 up_read(&mm->mmap_sem);
1863 audit_log_format(ab, " exe=(null)");
1864 audit_log_task_context(ab);
1866 EXPORT_SYMBOL(audit_log_task_info);
1869 * audit_log_link_denied - report a link restriction denial
1870 * @operation: specific link opreation
1871 * @link: the path that triggered the restriction
1873 void audit_log_link_denied(const char *operation, struct path *link)
1875 struct audit_buffer *ab;
1876 struct audit_names *name;
1878 name = kzalloc(sizeof(*name), GFP_NOFS);
1882 /* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */
1883 ab = audit_log_start(current->audit_context, GFP_KERNEL,
1887 audit_log_format(ab, "op=%s", operation);
1888 audit_log_task_info(ab, current);
1889 audit_log_format(ab, " res=0");
1892 /* Generate AUDIT_PATH record with object. */
1893 name->type = AUDIT_TYPE_NORMAL;
1894 audit_copy_inode(name, link->dentry, link->dentry->d_inode);
1895 audit_log_name(current->audit_context, name, link, 0, NULL);
1901 * audit_log_end - end one audit record
1902 * @ab: the audit_buffer
1904 * The netlink_* functions cannot be called inside an irq context, so
1905 * the audit buffer is placed on a queue and a tasklet is scheduled to
1906 * remove them from the queue outside the irq context. May be called in
1909 void audit_log_end(struct audit_buffer *ab)
1913 if (!audit_rate_check()) {
1914 audit_log_lost("rate limit exceeded");
1916 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
1917 nlh->nlmsg_len = ab->skb->len - NLMSG_HDRLEN;
1920 skb_queue_tail(&audit_skb_queue, ab->skb);
1921 wake_up_interruptible(&kauditd_wait);
1923 audit_printk_skb(ab->skb);
1927 audit_buffer_free(ab);
1931 * audit_log - Log an audit record
1932 * @ctx: audit context
1933 * @gfp_mask: type of allocation
1934 * @type: audit message type
1935 * @fmt: format string to use
1936 * @...: variable parameters matching the format string
1938 * This is a convenience function that calls audit_log_start,
1939 * audit_log_vformat, and audit_log_end. It may be called
1942 void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
1943 const char *fmt, ...)
1945 struct audit_buffer *ab;
1948 ab = audit_log_start(ctx, gfp_mask, type);
1950 va_start(args, fmt);
1951 audit_log_vformat(ab, fmt, args);
1957 #ifdef CONFIG_SECURITY
1959 * audit_log_secctx - Converts and logs SELinux context
1961 * @secid: security number
1963 * This is a helper function that calls security_secid_to_secctx to convert
1964 * secid to secctx and then adds the (converted) SELinux context to the audit
1965 * log by calling audit_log_format, thus also preventing leak of internal secid
1966 * to userspace. If secid cannot be converted audit_panic is called.
1968 void audit_log_secctx(struct audit_buffer *ab, u32 secid)
1973 if (security_secid_to_secctx(secid, &secctx, &len)) {
1974 audit_panic("Cannot convert secid to context");
1976 audit_log_format(ab, " obj=%s", secctx);
1977 security_release_secctx(secctx, len);
1980 EXPORT_SYMBOL(audit_log_secctx);
1983 EXPORT_SYMBOL(audit_log_start);
1984 EXPORT_SYMBOL(audit_log_end);
1985 EXPORT_SYMBOL(audit_log_format);
1986 EXPORT_SYMBOL(audit_log);