1 /* auditfilter.c -- filtering of audit events
3 * Copyright 2003-2004 Red Hat, Inc.
4 * Copyright 2005 Hewlett-Packard Development Company, L.P.
5 * Copyright 2005 IBM Corporation
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/kernel.h>
23 #include <linux/audit.h>
24 #include <linux/kthread.h>
25 #include <linux/mutex.h>
27 #include <linux/namei.h>
28 #include <linux/netlink.h>
29 #include <linux/sched.h>
30 #include <linux/slab.h>
31 #include <linux/security.h>
32 #include <net/net_namespace.h>
39 * Synchronizes writes and blocking reads of audit's filterlist
40 * data. Rcu is used to traverse the filterlist and access
41 * contents of structs audit_entry, audit_watch and opaque
42 * LSM rules during filtering. If modified, these structures
43 * must be copied and replace their counterparts in the filterlist.
44 * An audit_parent struct is not accessed during filtering, so may
45 * be written directly provided audit_filter_mutex is held.
48 /* Audit filter lists, defined in <linux/audit.h> */
49 struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
50 LIST_HEAD_INIT(audit_filter_list[0]),
51 LIST_HEAD_INIT(audit_filter_list[1]),
52 LIST_HEAD_INIT(audit_filter_list[2]),
53 LIST_HEAD_INIT(audit_filter_list[3]),
54 LIST_HEAD_INIT(audit_filter_list[4]),
55 LIST_HEAD_INIT(audit_filter_list[5]),
56 #if AUDIT_NR_FILTERS != 6
57 #error Fix audit_filter_list initialiser
60 static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = {
61 LIST_HEAD_INIT(audit_rules_list[0]),
62 LIST_HEAD_INIT(audit_rules_list[1]),
63 LIST_HEAD_INIT(audit_rules_list[2]),
64 LIST_HEAD_INIT(audit_rules_list[3]),
65 LIST_HEAD_INIT(audit_rules_list[4]),
66 LIST_HEAD_INIT(audit_rules_list[5]),
69 DEFINE_MUTEX(audit_filter_mutex);
71 static inline void audit_free_rule(struct audit_entry *e)
74 struct audit_krule *erule = &e->rule;
76 /* some rules don't have associated watches */
78 audit_put_watch(erule->watch);
80 for (i = 0; i < erule->field_count; i++) {
81 struct audit_field *f = &erule->fields[i];
83 security_audit_rule_free(f->lsm_rule);
86 kfree(erule->filterkey);
90 void audit_free_rule_rcu(struct rcu_head *head)
92 struct audit_entry *e = container_of(head, struct audit_entry, rcu);
96 /* Initialize an audit filterlist entry. */
97 static inline struct audit_entry *audit_init_entry(u32 field_count)
99 struct audit_entry *entry;
100 struct audit_field *fields;
102 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
103 if (unlikely(!entry))
106 fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL);
107 if (unlikely(!fields)) {
111 entry->rule.fields = fields;
116 /* Unpack a filter field's string representation from user-space
118 char *audit_unpack_string(void **bufp, size_t *remain, size_t len)
122 if (!*bufp || (len == 0) || (len > *remain))
123 return ERR_PTR(-EINVAL);
125 /* Of the currently implemented string fields, PATH_MAX
126 * defines the longest valid length.
129 return ERR_PTR(-ENAMETOOLONG);
131 str = kmalloc(len + 1, GFP_KERNEL);
133 return ERR_PTR(-ENOMEM);
135 memcpy(str, *bufp, len);
143 /* Translate an inode field to kernel respresentation. */
144 static inline int audit_to_inode(struct audit_krule *krule,
145 struct audit_field *f)
147 if (krule->listnr != AUDIT_FILTER_EXIT ||
148 krule->watch || krule->inode_f || krule->tree ||
149 (f->op != Audit_equal && f->op != Audit_not_equal))
156 static __u32 *classes[AUDIT_SYSCALL_CLASSES];
158 int __init audit_register_class(int class, unsigned *list)
160 __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL);
163 while (*list != ~0U) {
164 unsigned n = *list++;
165 if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) {
169 p[AUDIT_WORD(n)] |= AUDIT_BIT(n);
171 if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) {
179 int audit_match_class(int class, unsigned syscall)
181 if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32))
183 if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class]))
185 return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall);
188 #ifdef CONFIG_AUDITSYSCALL
189 static inline int audit_match_class_bits(int class, u32 *mask)
193 if (classes[class]) {
194 for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
195 if (mask[i] & classes[class][i])
201 static int audit_match_signal(struct audit_entry *entry)
203 struct audit_field *arch = entry->rule.arch_f;
206 /* When arch is unspecified, we must check both masks on biarch
207 * as syscall number alone is ambiguous. */
208 return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
210 audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
214 switch(audit_classify_arch(arch->val)) {
216 return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
218 case 1: /* 32bit on biarch */
219 return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
227 /* Common user-space to kernel rule translation. */
228 static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule)
231 struct audit_entry *entry;
235 listnr = rule->flags & ~AUDIT_FILTER_PREPEND;
239 #ifdef CONFIG_AUDITSYSCALL
240 case AUDIT_FILTER_ENTRY:
241 if (rule->action == AUDIT_ALWAYS)
243 case AUDIT_FILTER_EXIT:
244 case AUDIT_FILTER_TASK:
246 case AUDIT_FILTER_USER:
247 case AUDIT_FILTER_TYPE:
250 if (unlikely(rule->action == AUDIT_POSSIBLE)) {
251 printk(KERN_ERR "AUDIT_POSSIBLE is deprecated\n");
254 if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS)
256 if (rule->field_count > AUDIT_MAX_FIELDS)
260 entry = audit_init_entry(rule->field_count);
264 entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND;
265 entry->rule.listnr = listnr;
266 entry->rule.action = rule->action;
267 entry->rule.field_count = rule->field_count;
269 for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
270 entry->rule.mask[i] = rule->mask[i];
272 for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) {
273 int bit = AUDIT_BITMASK_SIZE * 32 - i - 1;
274 __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)];
277 if (!(*p & AUDIT_BIT(bit)))
279 *p &= ~AUDIT_BIT(bit);
283 for (j = 0; j < AUDIT_BITMASK_SIZE; j++)
284 entry->rule.mask[j] |= class[j];
294 static u32 audit_ops[] =
296 [Audit_equal] = AUDIT_EQUAL,
297 [Audit_not_equal] = AUDIT_NOT_EQUAL,
298 [Audit_bitmask] = AUDIT_BIT_MASK,
299 [Audit_bittest] = AUDIT_BIT_TEST,
300 [Audit_lt] = AUDIT_LESS_THAN,
301 [Audit_gt] = AUDIT_GREATER_THAN,
302 [Audit_le] = AUDIT_LESS_THAN_OR_EQUAL,
303 [Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL,
306 static u32 audit_to_op(u32 op)
309 for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++)
314 /* check if an audit field is valid */
315 static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
319 if (entry->rule.listnr != AUDIT_FILTER_TYPE &&
320 entry->rule.listnr != AUDIT_FILTER_USER)
348 /* bit ops are only useful on syscall args */
349 if (f->op == Audit_bitmask || f->op == Audit_bittest)
356 case AUDIT_SUBJ_USER:
357 case AUDIT_SUBJ_ROLE:
358 case AUDIT_SUBJ_TYPE:
364 case AUDIT_OBJ_LEV_LOW:
365 case AUDIT_OBJ_LEV_HIGH:
368 case AUDIT_FILTERKEY:
370 case AUDIT_LOGINUID_SET:
371 if ((f->val != 0) && (f->val != 1))
375 if (f->op != Audit_not_equal && f->op != Audit_equal)
383 if (f->val & ~S_IFMT)
386 case AUDIT_FIELD_COMPARE:
387 if (f->val > AUDIT_MAX_FIELD_COMPARE)
394 /* Translate struct audit_rule_data to kernel's rule respresentation. */
395 static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
399 struct audit_entry *entry;
401 size_t remain = datasz - sizeof(struct audit_rule_data);
405 entry = audit_to_entry_common((struct audit_rule *)data);
410 entry->rule.vers_ops = 2;
411 for (i = 0; i < data->field_count; i++) {
412 struct audit_field *f = &entry->rule.fields[i];
416 f->op = audit_to_op(data->fieldflags[i]);
417 if (f->op == Audit_bad)
420 f->type = data->fields[i];
421 f->val = data->values[i];
422 f->uid = INVALID_UID;
423 f->gid = INVALID_GID;
427 /* Support legacy tests for a valid loginuid */
428 if ((f->type == AUDIT_LOGINUID) && (f->val == AUDIT_UID_UNSET)) {
429 f->type = AUDIT_LOGINUID_SET;
433 err = audit_field_valid(entry, f);
445 f->uid = make_kuid(current_user_ns(), f->val);
446 if (!uid_valid(f->uid))
454 f->gid = make_kgid(current_user_ns(), f->val);
455 if (!gid_valid(f->gid))
459 entry->rule.arch_f = f;
461 case AUDIT_SUBJ_USER:
462 case AUDIT_SUBJ_ROLE:
463 case AUDIT_SUBJ_TYPE:
469 case AUDIT_OBJ_LEV_LOW:
470 case AUDIT_OBJ_LEV_HIGH:
471 str = audit_unpack_string(&bufp, &remain, f->val);
474 entry->rule.buflen += f->val;
476 err = security_audit_rule_init(f->type, f->op, str,
477 (void **)&f->lsm_rule);
478 /* Keep currently invalid fields around in case they
479 * become valid after a policy reload. */
480 if (err == -EINVAL) {
481 printk(KERN_WARNING "audit rule for LSM "
482 "\'%s\' is invalid\n", str);
492 str = audit_unpack_string(&bufp, &remain, f->val);
495 entry->rule.buflen += f->val;
497 err = audit_to_watch(&entry->rule, str, f->val, f->op);
504 str = audit_unpack_string(&bufp, &remain, f->val);
507 entry->rule.buflen += f->val;
509 err = audit_make_tree(&entry->rule, str, f->op);
515 err = audit_to_inode(&entry->rule, f);
519 case AUDIT_FILTERKEY:
520 if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN)
522 str = audit_unpack_string(&bufp, &remain, f->val);
525 entry->rule.buflen += f->val;
526 entry->rule.filterkey = str;
531 if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
532 entry->rule.inode_f = NULL;
538 if (entry->rule.watch)
539 audit_put_watch(entry->rule.watch); /* matches initial get */
540 if (entry->rule.tree)
541 audit_put_tree(entry->rule.tree); /* that's the temporary one */
542 audit_free_rule(entry);
546 /* Pack a filter field's string representation into data block. */
547 static inline size_t audit_pack_string(void **bufp, const char *str)
549 size_t len = strlen(str);
551 memcpy(*bufp, str, len);
557 /* Translate kernel rule respresentation to struct audit_rule_data. */
558 static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
560 struct audit_rule_data *data;
564 data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL);
567 memset(data, 0, sizeof(*data));
569 data->flags = krule->flags | krule->listnr;
570 data->action = krule->action;
571 data->field_count = krule->field_count;
573 for (i = 0; i < data->field_count; i++) {
574 struct audit_field *f = &krule->fields[i];
576 data->fields[i] = f->type;
577 data->fieldflags[i] = audit_ops[f->op];
579 case AUDIT_SUBJ_USER:
580 case AUDIT_SUBJ_ROLE:
581 case AUDIT_SUBJ_TYPE:
587 case AUDIT_OBJ_LEV_LOW:
588 case AUDIT_OBJ_LEV_HIGH:
589 data->buflen += data->values[i] =
590 audit_pack_string(&bufp, f->lsm_str);
593 data->buflen += data->values[i] =
594 audit_pack_string(&bufp,
595 audit_watch_path(krule->watch));
598 data->buflen += data->values[i] =
599 audit_pack_string(&bufp,
600 audit_tree_path(krule->tree));
602 case AUDIT_FILTERKEY:
603 data->buflen += data->values[i] =
604 audit_pack_string(&bufp, krule->filterkey);
607 data->values[i] = f->val;
610 for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i];
615 /* Compare two rules in kernel format. Considered success if rules
617 static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b)
621 if (a->flags != b->flags ||
622 a->listnr != b->listnr ||
623 a->action != b->action ||
624 a->field_count != b->field_count)
627 for (i = 0; i < a->field_count; i++) {
628 if (a->fields[i].type != b->fields[i].type ||
629 a->fields[i].op != b->fields[i].op)
632 switch(a->fields[i].type) {
633 case AUDIT_SUBJ_USER:
634 case AUDIT_SUBJ_ROLE:
635 case AUDIT_SUBJ_TYPE:
641 case AUDIT_OBJ_LEV_LOW:
642 case AUDIT_OBJ_LEV_HIGH:
643 if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str))
647 if (strcmp(audit_watch_path(a->watch),
648 audit_watch_path(b->watch)))
652 if (strcmp(audit_tree_path(a->tree),
653 audit_tree_path(b->tree)))
656 case AUDIT_FILTERKEY:
657 /* both filterkeys exist based on above type compare */
658 if (strcmp(a->filterkey, b->filterkey))
667 if (!uid_eq(a->fields[i].uid, b->fields[i].uid))
675 if (!gid_eq(a->fields[i].gid, b->fields[i].gid))
679 if (a->fields[i].val != b->fields[i].val)
684 for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
685 if (a->mask[i] != b->mask[i])
691 /* Duplicate LSM field information. The lsm_rule is opaque, so must be
693 static inline int audit_dupe_lsm_field(struct audit_field *df,
694 struct audit_field *sf)
699 /* our own copy of lsm_str */
700 lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL);
701 if (unlikely(!lsm_str))
703 df->lsm_str = lsm_str;
705 /* our own (refreshed) copy of lsm_rule */
706 ret = security_audit_rule_init(df->type, df->op, df->lsm_str,
707 (void **)&df->lsm_rule);
708 /* Keep currently invalid fields around in case they
709 * become valid after a policy reload. */
710 if (ret == -EINVAL) {
711 printk(KERN_WARNING "audit rule for LSM \'%s\' is "
712 "invalid\n", df->lsm_str);
719 /* Duplicate an audit rule. This will be a deep copy with the exception
720 * of the watch - that pointer is carried over. The LSM specific fields
721 * will be updated in the copy. The point is to be able to replace the old
722 * rule with the new rule in the filterlist, then free the old rule.
723 * The rlist element is undefined; list manipulations are handled apart from
724 * the initial copy. */
725 struct audit_entry *audit_dupe_rule(struct audit_krule *old)
727 u32 fcount = old->field_count;
728 struct audit_entry *entry;
729 struct audit_krule *new;
733 entry = audit_init_entry(fcount);
734 if (unlikely(!entry))
735 return ERR_PTR(-ENOMEM);
738 new->vers_ops = old->vers_ops;
739 new->flags = old->flags;
740 new->listnr = old->listnr;
741 new->action = old->action;
742 for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
743 new->mask[i] = old->mask[i];
744 new->prio = old->prio;
745 new->buflen = old->buflen;
746 new->inode_f = old->inode_f;
747 new->field_count = old->field_count;
750 * note that we are OK with not refcounting here; audit_match_tree()
751 * never dereferences tree and we can't get false positives there
752 * since we'd have to have rule gone from the list *and* removed
753 * before the chunks found by lookup had been allocated, i.e. before
754 * the beginning of list scan.
756 new->tree = old->tree;
757 memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount);
759 /* deep copy this information, updating the lsm_rule fields, because
760 * the originals will all be freed when the old rule is freed. */
761 for (i = 0; i < fcount; i++) {
762 switch (new->fields[i].type) {
763 case AUDIT_SUBJ_USER:
764 case AUDIT_SUBJ_ROLE:
765 case AUDIT_SUBJ_TYPE:
771 case AUDIT_OBJ_LEV_LOW:
772 case AUDIT_OBJ_LEV_HIGH:
773 err = audit_dupe_lsm_field(&new->fields[i],
776 case AUDIT_FILTERKEY:
777 fk = kstrdup(old->filterkey, GFP_KERNEL);
784 audit_free_rule(entry);
790 audit_get_watch(old->watch);
791 new->watch = old->watch;
797 /* Find an existing audit rule.
798 * Caller must hold audit_filter_mutex to prevent stale rule data. */
799 static struct audit_entry *audit_find_rule(struct audit_entry *entry,
800 struct list_head **p)
802 struct audit_entry *e, *found = NULL;
803 struct list_head *list;
806 if (entry->rule.inode_f) {
807 h = audit_hash_ino(entry->rule.inode_f->val);
808 *p = list = &audit_inode_hash[h];
809 } else if (entry->rule.watch) {
810 /* we don't know the inode number, so must walk entire hash */
811 for (h = 0; h < AUDIT_INODE_BUCKETS; h++) {
812 list = &audit_inode_hash[h];
813 list_for_each_entry(e, list, list)
814 if (!audit_compare_rule(&entry->rule, &e->rule)) {
821 *p = list = &audit_filter_list[entry->rule.listnr];
824 list_for_each_entry(e, list, list)
825 if (!audit_compare_rule(&entry->rule, &e->rule)) {
834 static u64 prio_low = ~0ULL/2;
835 static u64 prio_high = ~0ULL/2 - 1;
837 /* Add rule to given filterlist if not a duplicate. */
838 static inline int audit_add_rule(struct audit_entry *entry)
840 struct audit_entry *e;
841 struct audit_watch *watch = entry->rule.watch;
842 struct audit_tree *tree = entry->rule.tree;
843 struct list_head *list;
845 #ifdef CONFIG_AUDITSYSCALL
848 /* If either of these, don't count towards total */
849 if (entry->rule.listnr == AUDIT_FILTER_USER ||
850 entry->rule.listnr == AUDIT_FILTER_TYPE)
854 mutex_lock(&audit_filter_mutex);
855 e = audit_find_rule(entry, &list);
857 mutex_unlock(&audit_filter_mutex);
859 /* normally audit_add_tree_rule() will free it on failure */
861 audit_put_tree(tree);
866 /* audit_filter_mutex is dropped and re-taken during this call */
867 err = audit_add_watch(&entry->rule, &list);
869 mutex_unlock(&audit_filter_mutex);
871 * normally audit_add_tree_rule() will free it
875 audit_put_tree(tree);
880 err = audit_add_tree_rule(&entry->rule);
882 mutex_unlock(&audit_filter_mutex);
887 entry->rule.prio = ~0ULL;
888 if (entry->rule.listnr == AUDIT_FILTER_EXIT) {
889 if (entry->rule.flags & AUDIT_FILTER_PREPEND)
890 entry->rule.prio = ++prio_high;
892 entry->rule.prio = --prio_low;
895 if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
896 list_add(&entry->rule.list,
897 &audit_rules_list[entry->rule.listnr]);
898 list_add_rcu(&entry->list, list);
899 entry->rule.flags &= ~AUDIT_FILTER_PREPEND;
901 list_add_tail(&entry->rule.list,
902 &audit_rules_list[entry->rule.listnr]);
903 list_add_tail_rcu(&entry->list, list);
905 #ifdef CONFIG_AUDITSYSCALL
909 if (!audit_match_signal(entry))
912 mutex_unlock(&audit_filter_mutex);
918 audit_put_watch(watch); /* tmp watch, matches initial get */
922 /* Remove an existing rule from filterlist. */
923 static inline int audit_del_rule(struct audit_entry *entry)
925 struct audit_entry *e;
926 struct audit_watch *watch = entry->rule.watch;
927 struct audit_tree *tree = entry->rule.tree;
928 struct list_head *list;
930 #ifdef CONFIG_AUDITSYSCALL
933 /* If either of these, don't count towards total */
934 if (entry->rule.listnr == AUDIT_FILTER_USER ||
935 entry->rule.listnr == AUDIT_FILTER_TYPE)
939 mutex_lock(&audit_filter_mutex);
940 e = audit_find_rule(entry, &list);
942 mutex_unlock(&audit_filter_mutex);
948 audit_remove_watch_rule(&e->rule);
951 audit_remove_tree_rule(&e->rule);
953 list_del_rcu(&e->list);
954 list_del(&e->rule.list);
955 call_rcu(&e->rcu, audit_free_rule_rcu);
957 #ifdef CONFIG_AUDITSYSCALL
961 if (!audit_match_signal(entry))
964 mutex_unlock(&audit_filter_mutex);
968 audit_put_watch(watch); /* match initial get */
970 audit_put_tree(tree); /* that's the temporary one */
975 /* List rules using struct audit_rule_data. */
976 static void audit_list_rules(__u32 portid, int seq, struct sk_buff_head *q)
979 struct audit_krule *r;
982 /* This is a blocking read, so use audit_filter_mutex instead of rcu
983 * iterator to sync with list writers. */
984 for (i=0; i<AUDIT_NR_FILTERS; i++) {
985 list_for_each_entry(r, &audit_rules_list[i], list) {
986 struct audit_rule_data *data;
988 data = audit_krule_to_data(r);
991 skb = audit_make_reply(portid, seq, AUDIT_LIST_RULES,
993 sizeof(*data) + data->buflen);
995 skb_queue_tail(q, skb);
999 skb = audit_make_reply(portid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0);
1001 skb_queue_tail(q, skb);
1004 /* Log rule additions and removals */
1005 static void audit_log_rule_change(char *action, struct audit_krule *rule, int res)
1007 struct audit_buffer *ab;
1008 uid_t loginuid = from_kuid(&init_user_ns, audit_get_loginuid(current));
1009 unsigned int sessionid = audit_get_sessionid(current);
1014 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
1017 audit_log_format(ab, "auid=%u ses=%u" ,loginuid, sessionid);
1018 audit_log_task_context(ab);
1019 audit_log_format(ab, " op=");
1020 audit_log_string(ab, action);
1021 audit_log_key(ab, rule->filterkey);
1022 audit_log_format(ab, " list=%d res=%d", rule->listnr, res);
1027 * audit_rule_change - apply all rules to the specified message type
1028 * @type: audit message type
1029 * @portid: target port id for netlink audit messages
1030 * @seq: netlink audit message sequence (serial) number
1031 * @data: payload data
1032 * @datasz: size of payload data
1034 int audit_rule_change(int type, __u32 portid, int seq, void *data,
1038 struct audit_entry *entry;
1041 case AUDIT_ADD_RULE:
1042 entry = audit_data_to_entry(data, datasz);
1044 return PTR_ERR(entry);
1046 err = audit_add_rule(entry);
1047 audit_log_rule_change("add rule", &entry->rule, !err);
1049 audit_free_rule(entry);
1051 case AUDIT_DEL_RULE:
1052 entry = audit_data_to_entry(data, datasz);
1054 return PTR_ERR(entry);
1056 err = audit_del_rule(entry);
1057 audit_log_rule_change("remove rule", &entry->rule, !err);
1058 audit_free_rule(entry);
1068 * audit_list_rules_send - list the audit rules
1069 * @portid: target portid for netlink audit messages
1070 * @seq: netlink audit message sequence (serial) number
1072 int audit_list_rules_send(__u32 portid, int seq)
1074 struct task_struct *tsk;
1075 struct audit_netlink_list *dest;
1078 /* We can't just spew out the rules here because we might fill
1079 * the available socket buffer space and deadlock waiting for
1080 * auditctl to read from it... which isn't ever going to
1081 * happen if we're actually running in the context of auditctl
1082 * trying to _send_ the stuff */
1084 dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL);
1087 dest->net = get_net(current->nsproxy->net_ns);
1088 dest->portid = portid;
1089 skb_queue_head_init(&dest->q);
1091 mutex_lock(&audit_filter_mutex);
1092 audit_list_rules(portid, seq, &dest->q);
1093 mutex_unlock(&audit_filter_mutex);
1095 tsk = kthread_run(audit_send_list, dest, "audit_send_list");
1097 skb_queue_purge(&dest->q);
1105 int audit_comparator(u32 left, u32 op, u32 right)
1109 return (left == right);
1110 case Audit_not_equal:
1111 return (left != right);
1113 return (left < right);
1115 return (left <= right);
1117 return (left > right);
1119 return (left >= right);
1121 return (left & right);
1123 return ((left & right) == right);
1130 int audit_uid_comparator(kuid_t left, u32 op, kuid_t right)
1134 return uid_eq(left, right);
1135 case Audit_not_equal:
1136 return !uid_eq(left, right);
1138 return uid_lt(left, right);
1140 return uid_lte(left, right);
1142 return uid_gt(left, right);
1144 return uid_gte(left, right);
1153 int audit_gid_comparator(kgid_t left, u32 op, kgid_t right)
1157 return gid_eq(left, right);
1158 case Audit_not_equal:
1159 return !gid_eq(left, right);
1161 return gid_lt(left, right);
1163 return gid_lte(left, right);
1165 return gid_gt(left, right);
1167 return gid_gte(left, right);
1177 * parent_len - find the length of the parent portion of a pathname
1178 * @path: pathname of which to determine length
1180 int parent_len(const char *path)
1185 plen = strlen(path);
1190 /* disregard trailing slashes */
1191 p = path + plen - 1;
1192 while ((*p == '/') && (p > path))
1195 /* walk backward until we find the next slash or hit beginning */
1196 while ((*p != '/') && (p > path))
1199 /* did we find a slash? Then increment to include it in path */
1207 * audit_compare_dname_path - compare given dentry name with last component in
1208 * given path. Return of 0 indicates a match.
1209 * @dname: dentry name that we're comparing
1210 * @path: full pathname that we're comparing
1211 * @parentlen: length of the parent if known. Passing in AUDIT_NAME_FULL
1212 * here indicates that we must compute this value.
1214 int audit_compare_dname_path(const char *dname, const char *path, int parentlen)
1219 dlen = strlen(dname);
1220 pathlen = strlen(path);
1224 parentlen = parentlen == AUDIT_NAME_FULL ? parent_len(path) : parentlen;
1225 if (pathlen - parentlen != dlen)
1228 p = path + parentlen;
1230 return strncmp(p, dname, dlen);
1233 static int audit_filter_user_rules(struct audit_krule *rule, int type,
1234 enum audit_state *state)
1238 for (i = 0; i < rule->field_count; i++) {
1239 struct audit_field *f = &rule->fields[i];
1245 result = audit_comparator(task_pid_vnr(current), f->op, f->val);
1248 result = audit_uid_comparator(current_uid(), f->op, f->uid);
1251 result = audit_gid_comparator(current_gid(), f->op, f->gid);
1253 case AUDIT_LOGINUID:
1254 result = audit_uid_comparator(audit_get_loginuid(current),
1257 case AUDIT_LOGINUID_SET:
1258 result = audit_comparator(audit_loginuid_set(current),
1262 result = audit_comparator(type, f->op, f->val);
1264 case AUDIT_SUBJ_USER:
1265 case AUDIT_SUBJ_ROLE:
1266 case AUDIT_SUBJ_TYPE:
1267 case AUDIT_SUBJ_SEN:
1268 case AUDIT_SUBJ_CLR:
1270 security_task_getsecid(current, &sid);
1271 result = security_audit_rule_match(sid,
1283 switch (rule->action) {
1284 case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
1285 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
1290 int audit_filter_user(int type)
1292 enum audit_state state = AUDIT_DISABLED;
1293 struct audit_entry *e;
1296 ret = 1; /* Audit by default */
1299 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) {
1300 rc = audit_filter_user_rules(&e->rule, type, &state);
1302 if (rc > 0 && state == AUDIT_DISABLED)
1312 int audit_filter_type(int type)
1314 struct audit_entry *e;
1318 if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE]))
1319 goto unlock_and_return;
1321 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE],
1324 for (i = 0; i < e->rule.field_count; i++) {
1325 struct audit_field *f = &e->rule.fields[i];
1326 if (f->type == AUDIT_MSGTYPE) {
1327 result = audit_comparator(type, f->op, f->val);
1333 goto unlock_and_return;
1340 static int update_lsm_rule(struct audit_krule *r)
1342 struct audit_entry *entry = container_of(r, struct audit_entry, rule);
1343 struct audit_entry *nentry;
1346 if (!security_audit_rule_known(r))
1349 nentry = audit_dupe_rule(r);
1350 if (IS_ERR(nentry)) {
1351 /* save the first error encountered for the
1353 err = PTR_ERR(nentry);
1354 audit_panic("error updating LSM filters");
1356 list_del(&r->rlist);
1357 list_del_rcu(&entry->list);
1360 if (r->watch || r->tree)
1361 list_replace_init(&r->rlist, &nentry->rule.rlist);
1362 list_replace_rcu(&entry->list, &nentry->list);
1363 list_replace(&r->list, &nentry->rule.list);
1365 call_rcu(&entry->rcu, audit_free_rule_rcu);
1370 /* This function will re-initialize the lsm_rule field of all applicable rules.
1371 * It will traverse the filter lists serarching for rules that contain LSM
1372 * specific filter fields. When such a rule is found, it is copied, the
1373 * LSM field is re-initialized, and the old rule is replaced with the
1375 int audit_update_lsm_rules(void)
1377 struct audit_krule *r, *n;
1380 /* audit_filter_mutex synchronizes the writers */
1381 mutex_lock(&audit_filter_mutex);
1383 for (i = 0; i < AUDIT_NR_FILTERS; i++) {
1384 list_for_each_entry_safe(r, n, &audit_rules_list[i], list) {
1385 int res = update_lsm_rule(r);
1390 mutex_unlock(&audit_filter_mutex);