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 * When set to zero, this means unlimited. */
106 static int audit_backlog_limit = 64;
107 #define AUDIT_BACKLOG_WAIT_TIME (60 * HZ)
108 static int audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
109 static int audit_backlog_wait_overflow = 0;
111 /* The identity of the user shutting down the audit system. */
112 kuid_t audit_sig_uid = INVALID_UID;
113 pid_t audit_sig_pid = -1;
114 u32 audit_sig_sid = 0;
116 /* Records can be lost in several ways:
117 0) [suppressed in audit_alloc]
118 1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
119 2) out of memory in audit_log_move [alloc_skb]
120 3) suppressed due to audit_rate_limit
121 4) suppressed due to audit_backlog_limit
123 static atomic_t audit_lost = ATOMIC_INIT(0);
125 /* The netlink socket. */
126 static struct sock *audit_sock;
129 /* Hash for inode-based rules */
130 struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
132 /* The audit_freelist is a list of pre-allocated audit buffers (if more
133 * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
134 * being placed on the freelist). */
135 static DEFINE_SPINLOCK(audit_freelist_lock);
136 static int audit_freelist_count;
137 static LIST_HEAD(audit_freelist);
139 static struct sk_buff_head audit_skb_queue;
140 /* queue of skbs to send to auditd when/if it comes back */
141 static struct sk_buff_head audit_skb_hold_queue;
142 static struct task_struct *kauditd_task;
143 static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
144 static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
146 static struct audit_features af = {.vers = AUDIT_FEATURE_VERSION,
151 static char *audit_feature_names[2] = {
152 "only_unset_loginuid",
153 "loginuid_immutable",
157 /* Serialize requests from userspace. */
158 DEFINE_MUTEX(audit_cmd_mutex);
160 /* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
161 * audit records. Since printk uses a 1024 byte buffer, this buffer
162 * should be at least that large. */
163 #define AUDIT_BUFSIZ 1024
165 /* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the
166 * audit_freelist. Doing so eliminates many kmalloc/kfree calls. */
167 #define AUDIT_MAXFREE (2*NR_CPUS)
169 /* The audit_buffer is used when formatting an audit record. The caller
170 * locks briefly to get the record off the freelist or to allocate the
171 * buffer, and locks briefly to send the buffer to the netlink layer or
172 * to place it on a transmit queue. Multiple audit_buffers can be in
173 * use simultaneously. */
174 struct audit_buffer {
175 struct list_head list;
176 struct sk_buff *skb; /* formatted skb ready to send */
177 struct audit_context *ctx; /* NULL or associated context */
187 static void audit_set_portid(struct audit_buffer *ab, __u32 portid)
190 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
191 nlh->nlmsg_pid = portid;
195 void audit_panic(const char *message)
197 switch (audit_failure)
199 case AUDIT_FAIL_SILENT:
201 case AUDIT_FAIL_PRINTK:
202 if (printk_ratelimit())
203 printk(KERN_ERR "audit: %s\n", message);
205 case AUDIT_FAIL_PANIC:
206 /* test audit_pid since printk is always losey, why bother? */
208 panic("audit: %s\n", message);
213 static inline int audit_rate_check(void)
215 static unsigned long last_check = 0;
216 static int messages = 0;
217 static DEFINE_SPINLOCK(lock);
220 unsigned long elapsed;
223 if (!audit_rate_limit) return 1;
225 spin_lock_irqsave(&lock, flags);
226 if (++messages < audit_rate_limit) {
230 elapsed = now - last_check;
237 spin_unlock_irqrestore(&lock, flags);
243 * audit_log_lost - conditionally log lost audit message event
244 * @message: the message stating reason for lost audit message
246 * Emit at least 1 message per second, even if audit_rate_check is
248 * Always increment the lost messages counter.
250 void audit_log_lost(const char *message)
252 static unsigned long last_msg = 0;
253 static DEFINE_SPINLOCK(lock);
258 atomic_inc(&audit_lost);
260 print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit);
263 spin_lock_irqsave(&lock, flags);
265 if (now - last_msg > HZ) {
269 spin_unlock_irqrestore(&lock, flags);
273 if (printk_ratelimit())
275 "audit: audit_lost=%d audit_rate_limit=%d "
276 "audit_backlog_limit=%d\n",
277 atomic_read(&audit_lost),
279 audit_backlog_limit);
280 audit_panic(message);
284 static int audit_log_config_change(char *function_name, int new, int old,
287 struct audit_buffer *ab;
290 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
293 audit_log_format(ab, "%s=%d old=%d", 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, int *to_change, int new)
305 int allow_changes, rc = 0, 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(int limit)
330 return audit_do_config_change("audit_rate_limit", &audit_rate_limit, limit);
333 static int audit_set_backlog_limit(int limit)
335 return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, limit);
338 static int audit_set_backlog_wait_time(int timeout)
340 return audit_do_config_change("audit_backlog_wait_time",
341 &audit_backlog_wait_time, timeout);
344 static int audit_set_enabled(int 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(int 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 printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, data);
399 audit_log_lost("printk limit exceeded\n");
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 printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
415 audit_log_lost("auditd disappeared\n");
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 = get_net_ns_by_pid(dest->pid);
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);
518 struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, int done,
519 int multi, const void *payload, int size)
522 struct nlmsghdr *nlh;
524 int flags = multi ? NLM_F_MULTI : 0;
525 int t = done ? NLMSG_DONE : type;
527 skb = nlmsg_new(size, GFP_KERNEL);
531 nlh = nlmsg_put(skb, portid, seq, t, size, flags);
534 data = nlmsg_data(nlh);
535 memcpy(data, payload, size);
543 static int audit_send_reply_thread(void *arg)
545 struct audit_reply *reply = (struct audit_reply *)arg;
546 struct net *net = get_net_ns_by_pid(reply->pid);
547 struct audit_net *aunet = net_generic(net, audit_net_id);
549 mutex_lock(&audit_cmd_mutex);
550 mutex_unlock(&audit_cmd_mutex);
552 /* Ignore failure. It'll only happen if the sender goes away,
553 because our timeout is set to infinite. */
554 netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0);
559 * audit_send_reply - send an audit reply message via netlink
560 * @portid: netlink port to which to send reply
561 * @seq: sequence number
562 * @type: audit message type
563 * @done: done (last) flag
564 * @multi: multi-part message flag
565 * @payload: payload data
566 * @size: payload size
568 * Allocates an skb, builds the netlink message, and sends it to the port id.
569 * No failure notifications.
571 static void audit_send_reply(__u32 portid, int seq, int type, int done,
572 int multi, const void *payload, int size)
575 struct task_struct *tsk;
576 struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
582 skb = audit_make_reply(portid, seq, type, done, multi, payload, size);
586 reply->portid = portid;
587 reply->pid = task_pid_vnr(current);
590 tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
599 * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
602 static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
606 /* Only support the initial namespaces for now. */
607 if ((current_user_ns() != &init_user_ns) ||
608 (task_active_pid_ns(current) != &init_pid_ns))
618 case AUDIT_GET_FEATURE:
619 case AUDIT_SET_FEATURE:
620 case AUDIT_LIST_RULES:
623 case AUDIT_SIGNAL_INFO:
627 case AUDIT_MAKE_EQUIV:
628 if (!capable(CAP_AUDIT_CONTROL))
632 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
633 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
634 if (!capable(CAP_AUDIT_WRITE))
637 default: /* bad msg */
644 static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
647 uid_t uid = from_kuid(&init_user_ns, current_uid());
649 if (!audit_enabled && msg_type != AUDIT_USER_AVC) {
654 *ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
657 audit_log_format(*ab, "pid=%d uid=%u", task_tgid_vnr(current), uid);
658 audit_log_session_info(*ab);
659 audit_log_task_context(*ab);
664 int is_audit_feature_set(int i)
666 return af.features & AUDIT_FEATURE_TO_MASK(i);
670 static int audit_get_feature(struct sk_buff *skb)
674 seq = nlmsg_hdr(skb)->nlmsg_seq;
676 audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0,
682 static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature,
683 u32 old_lock, u32 new_lock, int res)
685 struct audit_buffer *ab;
687 if (audit_enabled == AUDIT_OFF)
690 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE);
691 audit_log_task_info(ab, current);
692 audit_log_format(ab, "feature=%s old=%d new=%d old_lock=%d new_lock=%d res=%d",
693 audit_feature_names[which], !!old_feature, !!new_feature,
694 !!old_lock, !!new_lock, res);
698 static int audit_set_feature(struct sk_buff *skb)
700 struct audit_features *uaf;
703 BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > sizeof(audit_feature_names)/sizeof(audit_feature_names[0]));
704 uaf = nlmsg_data(nlmsg_hdr(skb));
706 /* if there is ever a version 2 we should handle that here */
708 for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
709 u32 feature = AUDIT_FEATURE_TO_MASK(i);
710 u32 old_feature, new_feature, old_lock, new_lock;
712 /* if we are not changing this feature, move along */
713 if (!(feature & uaf->mask))
716 old_feature = af.features & feature;
717 new_feature = uaf->features & feature;
718 new_lock = (uaf->lock | af.lock) & feature;
719 old_lock = af.lock & feature;
721 /* are we changing a locked feature? */
722 if (old_lock && (new_feature != old_feature)) {
723 audit_log_feature_change(i, old_feature, new_feature,
724 old_lock, new_lock, 0);
728 /* nothing invalid, do the changes */
729 for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
730 u32 feature = AUDIT_FEATURE_TO_MASK(i);
731 u32 old_feature, new_feature, old_lock, new_lock;
733 /* if we are not changing this feature, move along */
734 if (!(feature & uaf->mask))
737 old_feature = af.features & feature;
738 new_feature = uaf->features & feature;
739 old_lock = af.lock & feature;
740 new_lock = (uaf->lock | af.lock) & feature;
742 if (new_feature != old_feature)
743 audit_log_feature_change(i, old_feature, new_feature,
744 old_lock, new_lock, 1);
747 af.features |= feature;
749 af.features &= ~feature;
756 static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
761 struct audit_buffer *ab;
762 u16 msg_type = nlh->nlmsg_type;
763 struct audit_sig_info *sig_data;
767 err = audit_netlink_ok(skb, msg_type);
771 /* As soon as there's any sign of userspace auditd,
772 * start kauditd to talk to it */
774 kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
775 if (IS_ERR(kauditd_task)) {
776 err = PTR_ERR(kauditd_task);
781 seq = nlh->nlmsg_seq;
782 data = nlmsg_data(nlh);
786 struct audit_status s;
787 memset(&s, 0, sizeof(s));
788 s.enabled = audit_enabled;
789 s.failure = audit_failure;
791 s.rate_limit = audit_rate_limit;
792 s.backlog_limit = audit_backlog_limit;
793 s.lost = atomic_read(&audit_lost);
794 s.backlog = skb_queue_len(&audit_skb_queue);
795 s.version = AUDIT_VERSION_LATEST;
796 s.backlog_wait_time = audit_backlog_wait_time;
797 audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0,
802 struct audit_status s;
803 memset(&s, 0, sizeof(s));
804 /* guard against past and future API changes */
805 memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
806 if (s.mask & AUDIT_STATUS_ENABLED) {
807 err = audit_set_enabled(s.enabled);
811 if (s.mask & AUDIT_STATUS_FAILURE) {
812 err = audit_set_failure(s.failure);
816 if (s.mask & AUDIT_STATUS_PID) {
819 if ((!new_pid) && (task_tgid_vnr(current) != audit_pid))
821 if (audit_enabled != AUDIT_OFF)
822 audit_log_config_change("audit_pid", new_pid, audit_pid, 1);
824 audit_nlk_portid = NETLINK_CB(skb).portid;
825 audit_sock = skb->sk;
827 if (s.mask & AUDIT_STATUS_RATE_LIMIT) {
828 err = audit_set_rate_limit(s.rate_limit);
832 if (s.mask & AUDIT_STATUS_BACKLOG_LIMIT) {
833 err = audit_set_backlog_limit(s.backlog_limit);
837 if (s.mask & AUDIT_STATUS_BACKLOG_WAIT_TIME) {
838 if (sizeof(s) > (size_t)nlh->nlmsg_len)
840 if (s.backlog_wait_time < 0 ||
841 s.backlog_wait_time > 10*AUDIT_BACKLOG_WAIT_TIME)
843 err = audit_set_backlog_wait_time(s.backlog_wait_time);
849 case AUDIT_GET_FEATURE:
850 err = audit_get_feature(skb);
854 case AUDIT_SET_FEATURE:
855 err = audit_set_feature(skb);
860 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
861 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
862 if (!audit_enabled && msg_type != AUDIT_USER_AVC)
865 err = audit_filter_user(msg_type);
866 if (err == 1) { /* match or error */
868 if (msg_type == AUDIT_USER_TTY) {
869 err = tty_audit_push_current();
873 mutex_unlock(&audit_cmd_mutex);
874 audit_log_common_recv_msg(&ab, msg_type);
875 if (msg_type != AUDIT_USER_TTY)
876 audit_log_format(ab, " msg='%.*s'",
877 AUDIT_MESSAGE_TEXT_MAX,
882 audit_log_format(ab, " data=");
883 size = nlmsg_len(nlh);
885 ((unsigned char *)data)[size - 1] == '\0')
887 audit_log_n_untrustedstring(ab, data, size);
889 audit_set_portid(ab, NETLINK_CB(skb).portid);
891 mutex_lock(&audit_cmd_mutex);
896 if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
898 if (audit_enabled == AUDIT_LOCKED) {
899 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
900 audit_log_format(ab, " audit_enabled=%d res=0", audit_enabled);
904 err = audit_rule_change(msg_type, NETLINK_CB(skb).portid,
905 seq, data, nlmsg_len(nlh));
907 case AUDIT_LIST_RULES:
908 err = audit_list_rules_send(NETLINK_CB(skb).portid, seq);
912 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
913 audit_log_format(ab, " op=trim res=1");
916 case AUDIT_MAKE_EQUIV: {
919 size_t msglen = nlmsg_len(nlh);
923 if (msglen < 2 * sizeof(u32))
925 memcpy(sizes, bufp, 2 * sizeof(u32));
926 bufp += 2 * sizeof(u32);
927 msglen -= 2 * sizeof(u32);
928 old = audit_unpack_string(&bufp, &msglen, sizes[0]);
933 new = audit_unpack_string(&bufp, &msglen, sizes[1]);
939 /* OK, here comes... */
940 err = audit_tag_tree(old, new);
942 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
944 audit_log_format(ab, " op=make_equiv old=");
945 audit_log_untrustedstring(ab, old);
946 audit_log_format(ab, " new=");
947 audit_log_untrustedstring(ab, new);
948 audit_log_format(ab, " res=%d", !err);
954 case AUDIT_SIGNAL_INFO:
957 err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
961 sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
964 security_release_secctx(ctx, len);
967 sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
968 sig_data->pid = audit_sig_pid;
970 memcpy(sig_data->ctx, ctx, len);
971 security_release_secctx(ctx, len);
973 audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_SIGNAL_INFO,
974 0, 0, sig_data, sizeof(*sig_data) + len);
977 case AUDIT_TTY_GET: {
978 struct audit_tty_status s;
979 struct task_struct *tsk = current;
981 spin_lock(&tsk->sighand->siglock);
982 s.enabled = tsk->signal->audit_tty;
983 s.log_passwd = tsk->signal->audit_tty_log_passwd;
984 spin_unlock(&tsk->sighand->siglock);
986 audit_send_reply(NETLINK_CB(skb).portid, seq,
987 AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
990 case AUDIT_TTY_SET: {
991 struct audit_tty_status s, old;
992 struct task_struct *tsk = current;
993 struct audit_buffer *ab;
996 spin_lock(&tsk->sighand->siglock);
997 old.enabled = tsk->signal->audit_tty;
998 old.log_passwd = tsk->signal->audit_tty_log_passwd;
999 spin_unlock(&tsk->sighand->siglock);
1001 memset(&s, 0, sizeof(s));
1002 /* guard against past and future API changes */
1003 memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
1004 if ((s.enabled == 0 || s.enabled == 1) &&
1005 (s.log_passwd == 0 || s.log_passwd == 1))
1007 audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
1008 audit_log_format(ab, " op=tty_set"
1009 " old-enabled=%d old-log_passwd=%d"
1010 " new-enabled=%d new-log_passwd=%d"
1012 old.enabled, old.log_passwd,
1013 s.enabled, s.log_passwd,
1017 spin_lock(&tsk->sighand->siglock);
1018 tsk->signal->audit_tty = s.enabled;
1019 tsk->signal->audit_tty_log_passwd = s.log_passwd;
1020 spin_unlock(&tsk->sighand->siglock);
1030 return err < 0 ? err : 0;
1034 * Get message from skb. Each message is processed by audit_receive_msg.
1035 * Malformed skbs with wrong length are discarded silently.
1037 static void audit_receive_skb(struct sk_buff *skb)
1039 struct nlmsghdr *nlh;
1041 * len MUST be signed for nlmsg_next to be able to dec it below 0
1042 * if the nlmsg_len was not aligned
1047 nlh = nlmsg_hdr(skb);
1050 while (nlmsg_ok(nlh, len)) {
1051 err = audit_receive_msg(skb, nlh);
1052 /* if err or if this message says it wants a response */
1053 if (err || (nlh->nlmsg_flags & NLM_F_ACK))
1054 netlink_ack(skb, nlh, err);
1056 nlh = nlmsg_next(nlh, &len);
1060 /* Receive messages from netlink socket. */
1061 static void audit_receive(struct sk_buff *skb)
1063 mutex_lock(&audit_cmd_mutex);
1064 audit_receive_skb(skb);
1065 mutex_unlock(&audit_cmd_mutex);
1068 static int __net_init audit_net_init(struct net *net)
1070 struct netlink_kernel_cfg cfg = {
1071 .input = audit_receive,
1074 struct audit_net *aunet = net_generic(net, audit_net_id);
1076 pr_info("audit: initializing netlink socket in namespace\n");
1078 aunet->nlsk = netlink_kernel_create(net, NETLINK_AUDIT, &cfg);
1079 if (aunet->nlsk == NULL) {
1080 audit_panic("cannot initialize netlink socket in namespace");
1083 aunet->nlsk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
1087 static void __net_exit audit_net_exit(struct net *net)
1089 struct audit_net *aunet = net_generic(net, audit_net_id);
1090 struct sock *sock = aunet->nlsk;
1091 if (sock == audit_sock) {
1096 rcu_assign_pointer(aunet->nlsk, NULL);
1098 netlink_kernel_release(sock);
1101 static struct pernet_operations __net_initdata audit_net_ops = {
1102 .init = audit_net_init,
1103 .exit = audit_net_exit,
1104 .id = &audit_net_id,
1105 .size = sizeof(struct audit_net),
1108 /* Initialize audit support at boot time. */
1109 static int __init audit_init(void)
1113 if (audit_initialized == AUDIT_DISABLED)
1116 pr_info("audit: initializing netlink subsys (%s)\n",
1117 audit_default ? "enabled" : "disabled");
1118 register_pernet_subsys(&audit_net_ops);
1120 skb_queue_head_init(&audit_skb_queue);
1121 skb_queue_head_init(&audit_skb_hold_queue);
1122 audit_initialized = AUDIT_INITIALIZED;
1123 audit_enabled = audit_default;
1124 audit_ever_enabled |= !!audit_default;
1126 audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
1128 for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
1129 INIT_LIST_HEAD(&audit_inode_hash[i]);
1133 __initcall(audit_init);
1135 /* Process kernel command-line parameter at boot time. audit=0 or audit=1. */
1136 static int __init audit_enable(char *str)
1138 audit_default = !!simple_strtol(str, NULL, 0);
1140 audit_initialized = AUDIT_DISABLED;
1142 pr_info("audit: %s\n", audit_default ?
1143 "enabled (after initialization)" : "disabled (until reboot)");
1147 __setup("audit=", audit_enable);
1149 /* Process kernel command-line parameter at boot time.
1150 * audit_backlog_limit=<n> */
1151 static int __init audit_backlog_limit_set(char *str)
1153 long int audit_backlog_limit_arg;
1154 pr_info("audit_backlog_limit: ");
1155 if (kstrtol(str, 0, &audit_backlog_limit_arg)) {
1156 printk("using default of %d, unable to parse %s\n",
1157 audit_backlog_limit, str);
1160 if (audit_backlog_limit_arg >= 0)
1161 audit_backlog_limit = (int)audit_backlog_limit_arg;
1162 printk("%d\n", audit_backlog_limit);
1166 __setup("audit_backlog_limit=", audit_backlog_limit_set);
1168 static void audit_buffer_free(struct audit_buffer *ab)
1170 unsigned long flags;
1178 spin_lock_irqsave(&audit_freelist_lock, flags);
1179 if (audit_freelist_count > AUDIT_MAXFREE)
1182 audit_freelist_count++;
1183 list_add(&ab->list, &audit_freelist);
1185 spin_unlock_irqrestore(&audit_freelist_lock, flags);
1188 static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
1189 gfp_t gfp_mask, int type)
1191 unsigned long flags;
1192 struct audit_buffer *ab = NULL;
1193 struct nlmsghdr *nlh;
1195 spin_lock_irqsave(&audit_freelist_lock, flags);
1196 if (!list_empty(&audit_freelist)) {
1197 ab = list_entry(audit_freelist.next,
1198 struct audit_buffer, list);
1199 list_del(&ab->list);
1200 --audit_freelist_count;
1202 spin_unlock_irqrestore(&audit_freelist_lock, flags);
1205 ab = kmalloc(sizeof(*ab), gfp_mask);
1211 ab->gfp_mask = gfp_mask;
1213 ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask);
1217 nlh = nlmsg_put(ab->skb, 0, 0, type, 0, 0);
1227 audit_buffer_free(ab);
1232 * audit_serial - compute a serial number for the audit record
1234 * Compute a serial number for the audit record. Audit records are
1235 * written to user-space as soon as they are generated, so a complete
1236 * audit record may be written in several pieces. The timestamp of the
1237 * record and this serial number are used by the user-space tools to
1238 * determine which pieces belong to the same audit record. The
1239 * (timestamp,serial) tuple is unique for each syscall and is live from
1240 * syscall entry to syscall exit.
1242 * NOTE: Another possibility is to store the formatted records off the
1243 * audit context (for those records that have a context), and emit them
1244 * all at syscall exit. However, this could delay the reporting of
1245 * significant errors until syscall exit (or never, if the system
1248 unsigned int audit_serial(void)
1250 static DEFINE_SPINLOCK(serial_lock);
1251 static unsigned int serial = 0;
1253 unsigned long flags;
1256 spin_lock_irqsave(&serial_lock, flags);
1259 } while (unlikely(!ret));
1260 spin_unlock_irqrestore(&serial_lock, flags);
1265 static inline void audit_get_stamp(struct audit_context *ctx,
1266 struct timespec *t, unsigned int *serial)
1268 if (!ctx || !auditsc_get_stamp(ctx, t, serial)) {
1270 *serial = audit_serial();
1275 * Wait for auditd to drain the queue a little
1277 static long wait_for_auditd(long sleep_time)
1279 DECLARE_WAITQUEUE(wait, current);
1280 set_current_state(TASK_UNINTERRUPTIBLE);
1281 add_wait_queue_exclusive(&audit_backlog_wait, &wait);
1283 if (audit_backlog_limit &&
1284 skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
1285 sleep_time = schedule_timeout(sleep_time);
1287 __set_current_state(TASK_RUNNING);
1288 remove_wait_queue(&audit_backlog_wait, &wait);
1294 * audit_log_start - obtain an audit buffer
1295 * @ctx: audit_context (may be NULL)
1296 * @gfp_mask: type of allocation
1297 * @type: audit message type
1299 * Returns audit_buffer pointer on success or NULL on error.
1301 * Obtain an audit buffer. This routine does locking to obtain the
1302 * audit buffer, but then no locking is required for calls to
1303 * audit_log_*format. If the task (ctx) is a task that is currently in a
1304 * syscall, then the syscall is marked as auditable and an audit record
1305 * will be written at syscall exit. If there is no associated task, then
1306 * task context (ctx) should be NULL.
1308 struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
1311 struct audit_buffer *ab = NULL;
1313 unsigned int uninitialized_var(serial);
1314 int reserve = 5; /* Allow atomic callers to go up to five
1315 entries over the normal backlog limit */
1316 unsigned long timeout_start = jiffies;
1318 if (audit_initialized != AUDIT_INITIALIZED)
1321 if (unlikely(audit_filter_type(type)))
1324 if (gfp_mask & __GFP_WAIT) {
1325 if (audit_pid && audit_pid == current->pid)
1326 gfp_mask &= ~__GFP_WAIT;
1331 while (audit_backlog_limit
1332 && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
1333 if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) {
1336 sleep_time = timeout_start + audit_backlog_wait_time - jiffies;
1337 if (sleep_time > 0) {
1338 sleep_time = wait_for_auditd(sleep_time);
1343 if (audit_rate_check() && printk_ratelimit())
1345 "audit: audit_backlog=%d > "
1346 "audit_backlog_limit=%d\n",
1347 skb_queue_len(&audit_skb_queue),
1348 audit_backlog_limit);
1349 audit_log_lost("backlog limit exceeded");
1350 audit_backlog_wait_time = audit_backlog_wait_overflow;
1351 wake_up(&audit_backlog_wait);
1355 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
1357 ab = audit_buffer_alloc(ctx, gfp_mask, type);
1359 audit_log_lost("out of memory in audit_log_start");
1363 audit_get_stamp(ab->ctx, &t, &serial);
1365 audit_log_format(ab, "audit(%lu.%03lu:%u): ",
1366 t.tv_sec, t.tv_nsec/1000000, serial);
1371 * audit_expand - expand skb in the audit buffer
1373 * @extra: space to add at tail of the skb
1375 * Returns 0 (no space) on failed expansion, or available space if
1378 static inline int audit_expand(struct audit_buffer *ab, int extra)
1380 struct sk_buff *skb = ab->skb;
1381 int oldtail = skb_tailroom(skb);
1382 int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask);
1383 int newtail = skb_tailroom(skb);
1386 audit_log_lost("out of memory in audit_expand");
1390 skb->truesize += newtail - oldtail;
1395 * Format an audit message into the audit buffer. If there isn't enough
1396 * room in the audit buffer, more room will be allocated and vsnprint
1397 * will be called a second time. Currently, we assume that a printk
1398 * can't format message larger than 1024 bytes, so we don't either.
1400 static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
1404 struct sk_buff *skb;
1412 avail = skb_tailroom(skb);
1414 avail = audit_expand(ab, AUDIT_BUFSIZ);
1418 va_copy(args2, args);
1419 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args);
1421 /* The printk buffer is 1024 bytes long, so if we get
1422 * here and AUDIT_BUFSIZ is at least 1024, then we can
1423 * log everything that printk could have logged. */
1424 avail = audit_expand(ab,
1425 max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
1428 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2);
1439 * audit_log_format - format a message into the audit buffer.
1441 * @fmt: format string
1442 * @...: optional parameters matching @fmt string
1444 * All the work is done in audit_log_vformat.
1446 void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
1452 va_start(args, fmt);
1453 audit_log_vformat(ab, fmt, args);
1458 * audit_log_hex - convert a buffer to hex and append it to the audit skb
1459 * @ab: the audit_buffer
1460 * @buf: buffer to convert to hex
1461 * @len: length of @buf to be converted
1463 * No return value; failure to expand is silently ignored.
1465 * This function will take the passed buf and convert it into a string of
1466 * ascii hex digits. The new string is placed onto the skb.
1468 void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
1471 int i, avail, new_len;
1473 struct sk_buff *skb;
1474 static const unsigned char *hex = "0123456789ABCDEF";
1481 avail = skb_tailroom(skb);
1483 if (new_len >= avail) {
1484 /* Round the buffer request up to the next multiple */
1485 new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1);
1486 avail = audit_expand(ab, new_len);
1491 ptr = skb_tail_pointer(skb);
1492 for (i=0; i<len; i++) {
1493 *ptr++ = hex[(buf[i] & 0xF0)>>4]; /* Upper nibble */
1494 *ptr++ = hex[buf[i] & 0x0F]; /* Lower nibble */
1497 skb_put(skb, len << 1); /* new string is twice the old string */
1501 * Format a string of no more than slen characters into the audit buffer,
1502 * enclosed in quote marks.
1504 void audit_log_n_string(struct audit_buffer *ab, const char *string,
1509 struct sk_buff *skb;
1516 avail = skb_tailroom(skb);
1517 new_len = slen + 3; /* enclosing quotes + null terminator */
1518 if (new_len > avail) {
1519 avail = audit_expand(ab, new_len);
1523 ptr = skb_tail_pointer(skb);
1525 memcpy(ptr, string, slen);
1529 skb_put(skb, slen + 2); /* don't include null terminator */
1533 * audit_string_contains_control - does a string need to be logged in hex
1534 * @string: string to be checked
1535 * @len: max length of the string to check
1537 int audit_string_contains_control(const char *string, size_t len)
1539 const unsigned char *p;
1540 for (p = string; p < (const unsigned char *)string + len; p++) {
1541 if (*p == '"' || *p < 0x21 || *p > 0x7e)
1548 * audit_log_n_untrustedstring - log a string that may contain random characters
1550 * @len: length of string (not including trailing null)
1551 * @string: string to be logged
1553 * This code will escape a string that is passed to it if the string
1554 * contains a control character, unprintable character, double quote mark,
1555 * or a space. Unescaped strings will start and end with a double quote mark.
1556 * Strings that are escaped are printed in hex (2 digits per char).
1558 * The caller specifies the number of characters in the string to log, which may
1559 * or may not be the entire string.
1561 void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string,
1564 if (audit_string_contains_control(string, len))
1565 audit_log_n_hex(ab, string, len);
1567 audit_log_n_string(ab, string, len);
1571 * audit_log_untrustedstring - log a string that may contain random characters
1573 * @string: string to be logged
1575 * Same as audit_log_n_untrustedstring(), except that strlen is used to
1576 * determine string length.
1578 void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
1580 audit_log_n_untrustedstring(ab, string, strlen(string));
1583 /* This is a helper-function to print the escaped d_path */
1584 void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
1585 const struct path *path)
1590 audit_log_format(ab, "%s", prefix);
1592 /* We will allow 11 spaces for ' (deleted)' to be appended */
1593 pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
1595 audit_log_string(ab, "<no_memory>");
1598 p = d_path(path, pathname, PATH_MAX+11);
1599 if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
1600 /* FIXME: can we save some information here? */
1601 audit_log_string(ab, "<too_long>");
1603 audit_log_untrustedstring(ab, p);
1607 void audit_log_session_info(struct audit_buffer *ab)
1609 unsigned int sessionid = audit_get_sessionid(current);
1610 uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current));
1612 audit_log_format(ab, " auid=%u ses=%u", auid, sessionid);
1615 void audit_log_key(struct audit_buffer *ab, char *key)
1617 audit_log_format(ab, " key=");
1619 audit_log_untrustedstring(ab, key);
1621 audit_log_format(ab, "(null)");
1624 void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
1628 audit_log_format(ab, " %s=", prefix);
1629 CAP_FOR_EACH_U32(i) {
1630 audit_log_format(ab, "%08x",
1631 cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
1635 void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1637 kernel_cap_t *perm = &name->fcap.permitted;
1638 kernel_cap_t *inh = &name->fcap.inheritable;
1641 if (!cap_isclear(*perm)) {
1642 audit_log_cap(ab, "cap_fp", perm);
1645 if (!cap_isclear(*inh)) {
1646 audit_log_cap(ab, "cap_fi", inh);
1651 audit_log_format(ab, " cap_fe=%d cap_fver=%x",
1652 name->fcap.fE, name->fcap_ver);
1655 static inline int audit_copy_fcaps(struct audit_names *name,
1656 const struct dentry *dentry)
1658 struct cpu_vfs_cap_data caps;
1664 rc = get_vfs_caps_from_disk(dentry, &caps);
1668 name->fcap.permitted = caps.permitted;
1669 name->fcap.inheritable = caps.inheritable;
1670 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
1671 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >>
1672 VFS_CAP_REVISION_SHIFT;
1677 /* Copy inode data into an audit_names. */
1678 void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
1679 const struct inode *inode)
1681 name->ino = inode->i_ino;
1682 name->dev = inode->i_sb->s_dev;
1683 name->mode = inode->i_mode;
1684 name->uid = inode->i_uid;
1685 name->gid = inode->i_gid;
1686 name->rdev = inode->i_rdev;
1687 security_inode_getsecid(inode, &name->osid);
1688 audit_copy_fcaps(name, dentry);
1692 * audit_log_name - produce AUDIT_PATH record from struct audit_names
1693 * @context: audit_context for the task
1694 * @n: audit_names structure with reportable details
1695 * @path: optional path to report instead of audit_names->name
1696 * @record_num: record number to report when handling a list of names
1697 * @call_panic: optional pointer to int that will be updated if secid fails
1699 void audit_log_name(struct audit_context *context, struct audit_names *n,
1700 struct path *path, int record_num, int *call_panic)
1702 struct audit_buffer *ab;
1703 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1707 audit_log_format(ab, "item=%d", record_num);
1710 audit_log_d_path(ab, " name=", path);
1712 switch (n->name_len) {
1713 case AUDIT_NAME_FULL:
1714 /* log the full path */
1715 audit_log_format(ab, " name=");
1716 audit_log_untrustedstring(ab, n->name->name);
1719 /* name was specified as a relative path and the
1720 * directory component is the cwd */
1721 audit_log_d_path(ab, " name=", &context->pwd);
1724 /* log the name's directory component */
1725 audit_log_format(ab, " name=");
1726 audit_log_n_untrustedstring(ab, n->name->name,
1730 audit_log_format(ab, " name=(null)");
1732 if (n->ino != (unsigned long)-1) {
1733 audit_log_format(ab, " inode=%lu"
1734 " dev=%02x:%02x mode=%#ho"
1735 " ouid=%u ogid=%u rdev=%02x:%02x",
1740 from_kuid(&init_user_ns, n->uid),
1741 from_kgid(&init_user_ns, n->gid),
1748 if (security_secid_to_secctx(
1749 n->osid, &ctx, &len)) {
1750 audit_log_format(ab, " osid=%u", n->osid);
1754 audit_log_format(ab, " obj=%s", ctx);
1755 security_release_secctx(ctx, len);
1759 /* log the audit_names record type */
1760 audit_log_format(ab, " nametype=");
1762 case AUDIT_TYPE_NORMAL:
1763 audit_log_format(ab, "NORMAL");
1765 case AUDIT_TYPE_PARENT:
1766 audit_log_format(ab, "PARENT");
1768 case AUDIT_TYPE_CHILD_DELETE:
1769 audit_log_format(ab, "DELETE");
1771 case AUDIT_TYPE_CHILD_CREATE:
1772 audit_log_format(ab, "CREATE");
1775 audit_log_format(ab, "UNKNOWN");
1779 audit_log_fcaps(ab, n);
1783 int audit_log_task_context(struct audit_buffer *ab)
1790 security_task_getsecid(current, &sid);
1794 error = security_secid_to_secctx(sid, &ctx, &len);
1796 if (error != -EINVAL)
1801 audit_log_format(ab, " subj=%s", ctx);
1802 security_release_secctx(ctx, len);
1806 audit_panic("error in audit_log_task_context");
1809 EXPORT_SYMBOL(audit_log_task_context);
1811 void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
1813 const struct cred *cred;
1814 char name[sizeof(tsk->comm)];
1815 struct mm_struct *mm = tsk->mm;
1821 /* tsk == current */
1822 cred = current_cred();
1824 spin_lock_irq(&tsk->sighand->siglock);
1825 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1826 tty = tsk->signal->tty->name;
1829 spin_unlock_irq(&tsk->sighand->siglock);
1831 audit_log_format(ab,
1832 " ppid=%ld pid=%d auid=%u uid=%u gid=%u"
1833 " euid=%u suid=%u fsuid=%u"
1834 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1837 from_kuid(&init_user_ns, audit_get_loginuid(tsk)),
1838 from_kuid(&init_user_ns, cred->uid),
1839 from_kgid(&init_user_ns, cred->gid),
1840 from_kuid(&init_user_ns, cred->euid),
1841 from_kuid(&init_user_ns, cred->suid),
1842 from_kuid(&init_user_ns, cred->fsuid),
1843 from_kgid(&init_user_ns, cred->egid),
1844 from_kgid(&init_user_ns, cred->sgid),
1845 from_kgid(&init_user_ns, cred->fsgid),
1846 tty, audit_get_sessionid(tsk));
1848 get_task_comm(name, tsk);
1849 audit_log_format(ab, " comm=");
1850 audit_log_untrustedstring(ab, name);
1853 down_read(&mm->mmap_sem);
1855 audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
1856 up_read(&mm->mmap_sem);
1858 audit_log_format(ab, " exe=(null)");
1859 audit_log_task_context(ab);
1861 EXPORT_SYMBOL(audit_log_task_info);
1864 * audit_log_link_denied - report a link restriction denial
1865 * @operation: specific link opreation
1866 * @link: the path that triggered the restriction
1868 void audit_log_link_denied(const char *operation, struct path *link)
1870 struct audit_buffer *ab;
1871 struct audit_names *name;
1873 name = kzalloc(sizeof(*name), GFP_NOFS);
1877 /* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */
1878 ab = audit_log_start(current->audit_context, GFP_KERNEL,
1882 audit_log_format(ab, "op=%s", operation);
1883 audit_log_task_info(ab, current);
1884 audit_log_format(ab, " res=0");
1887 /* Generate AUDIT_PATH record with object. */
1888 name->type = AUDIT_TYPE_NORMAL;
1889 audit_copy_inode(name, link->dentry, link->dentry->d_inode);
1890 audit_log_name(current->audit_context, name, link, 0, NULL);
1896 * audit_log_end - end one audit record
1897 * @ab: the audit_buffer
1899 * The netlink_* functions cannot be called inside an irq context, so
1900 * the audit buffer is placed on a queue and a tasklet is scheduled to
1901 * remove them from the queue outside the irq context. May be called in
1904 void audit_log_end(struct audit_buffer *ab)
1908 if (!audit_rate_check()) {
1909 audit_log_lost("rate limit exceeded");
1911 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
1912 nlh->nlmsg_len = ab->skb->len - NLMSG_HDRLEN;
1915 skb_queue_tail(&audit_skb_queue, ab->skb);
1916 wake_up_interruptible(&kauditd_wait);
1918 audit_printk_skb(ab->skb);
1922 audit_buffer_free(ab);
1926 * audit_log - Log an audit record
1927 * @ctx: audit context
1928 * @gfp_mask: type of allocation
1929 * @type: audit message type
1930 * @fmt: format string to use
1931 * @...: variable parameters matching the format string
1933 * This is a convenience function that calls audit_log_start,
1934 * audit_log_vformat, and audit_log_end. It may be called
1937 void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
1938 const char *fmt, ...)
1940 struct audit_buffer *ab;
1943 ab = audit_log_start(ctx, gfp_mask, type);
1945 va_start(args, fmt);
1946 audit_log_vformat(ab, fmt, args);
1952 #ifdef CONFIG_SECURITY
1954 * audit_log_secctx - Converts and logs SELinux context
1956 * @secid: security number
1958 * This is a helper function that calls security_secid_to_secctx to convert
1959 * secid to secctx and then adds the (converted) SELinux context to the audit
1960 * log by calling audit_log_format, thus also preventing leak of internal secid
1961 * to userspace. If secid cannot be converted audit_panic is called.
1963 void audit_log_secctx(struct audit_buffer *ab, u32 secid)
1968 if (security_secid_to_secctx(secid, &secctx, &len)) {
1969 audit_panic("Cannot convert secid to context");
1971 audit_log_format(ab, " obj=%s", secctx);
1972 security_release_secctx(secctx, len);
1975 EXPORT_SYMBOL(audit_log_secctx);
1978 EXPORT_SYMBOL(audit_log_start);
1979 EXPORT_SYMBOL(audit_log_end);
1980 EXPORT_SYMBOL(audit_log_format);
1981 EXPORT_SYMBOL(audit_log);