1 /* auditsc.c -- System-call auditing support
2 * Handles all system-call specific auditing features.
4 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
5 * Copyright 2005 Hewlett-Packard Development Company, L.P.
6 * Copyright (C) 2005, 2006 IBM Corporation
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
25 * Many of the ideas implemented here are from Stephen C. Tweedie,
26 * especially the idea of avoiding a copy by using getname.
28 * The method for actual interception of syscall entry and exit (not in
29 * this file -- see entry.S) is based on a GPL'd patch written by
30 * okir@suse.de and Copyright 2003 SuSE Linux AG.
32 * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
35 * The support of additional filter rules compares (>, <, >=, <=) was
36 * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
38 * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
39 * filesystem information.
41 * Subject and object context labeling support added by <danjones@us.ibm.com>
42 * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
45 #include <linux/init.h>
46 #include <asm/types.h>
47 #include <asm/atomic.h>
48 #include <asm/types.h>
50 #include <linux/namei.h>
52 #include <linux/module.h>
53 #include <linux/mount.h>
54 #include <linux/socket.h>
55 #include <linux/mqueue.h>
56 #include <linux/audit.h>
57 #include <linux/personality.h>
58 #include <linux/time.h>
59 #include <linux/netlink.h>
60 #include <linux/compiler.h>
61 #include <asm/unistd.h>
62 #include <linux/security.h>
63 #include <linux/list.h>
64 #include <linux/tty.h>
65 #include <linux/selinux.h>
66 #include <linux/binfmts.h>
67 #include <linux/syscalls.h>
71 extern struct list_head audit_filter_list[];
73 /* No syscall auditing will take place unless audit_enabled != 0. */
74 extern int audit_enabled;
76 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
77 * for saving names from getname(). */
78 #define AUDIT_NAMES 20
80 /* AUDIT_NAMES_RESERVED is the number of slots we reserve in the
81 * audit_context from being used for nameless inodes from
83 #define AUDIT_NAMES_RESERVED 7
85 /* Indicates that audit should log the full pathname. */
86 #define AUDIT_NAME_FULL -1
88 /* number of audit rules */
91 /* When fs/namei.c:getname() is called, we store the pointer in name and
92 * we don't let putname() free it (instead we free all of the saved
93 * pointers at syscall exit time).
95 * Further, in fs/namei.c:path_lookup() we store the inode and device. */
98 int name_len; /* number of name's characters to log */
99 unsigned name_put; /* call __putname() for this name */
109 struct audit_aux_data {
110 struct audit_aux_data *next;
114 #define AUDIT_AUX_IPCPERM 0
116 struct audit_aux_data_mq_open {
117 struct audit_aux_data d;
123 struct audit_aux_data_mq_sendrecv {
124 struct audit_aux_data d;
127 unsigned int msg_prio;
128 struct timespec abs_timeout;
131 struct audit_aux_data_mq_notify {
132 struct audit_aux_data d;
134 struct sigevent notification;
137 struct audit_aux_data_mq_getsetattr {
138 struct audit_aux_data d;
140 struct mq_attr mqstat;
143 struct audit_aux_data_ipcctl {
144 struct audit_aux_data d;
146 unsigned long qbytes;
153 struct audit_aux_data_execve {
154 struct audit_aux_data d;
160 struct audit_aux_data_socketcall {
161 struct audit_aux_data d;
163 unsigned long args[0];
166 struct audit_aux_data_sockaddr {
167 struct audit_aux_data d;
172 struct audit_aux_data_path {
173 struct audit_aux_data d;
174 struct dentry *dentry;
175 struct vfsmount *mnt;
178 /* The per-task audit context. */
179 struct audit_context {
180 int dummy; /* must be the first element */
181 int in_syscall; /* 1 if task is in a syscall */
182 enum audit_state state;
183 unsigned int serial; /* serial number for record */
184 struct timespec ctime; /* time of syscall entry */
185 uid_t loginuid; /* login uid (identity) */
186 int major; /* syscall number */
187 unsigned long argv[4]; /* syscall arguments */
188 int return_valid; /* return code is valid */
189 long return_code;/* syscall return code */
190 int auditable; /* 1 if record should be written */
192 struct audit_names names[AUDIT_NAMES];
193 char * filterkey; /* key for rule that triggered record */
195 struct vfsmount * pwdmnt;
196 struct audit_context *previous; /* For nested syscalls */
197 struct audit_aux_data *aux;
199 /* Save things to print about task_struct */
201 uid_t uid, euid, suid, fsuid;
202 gid_t gid, egid, sgid, fsgid;
203 unsigned long personality;
212 /* Determine if any context name data matches a rule's watch data */
213 /* Compare a task_struct with an audit_rule. Return 1 on match, 0
215 static int audit_filter_rules(struct task_struct *tsk,
216 struct audit_krule *rule,
217 struct audit_context *ctx,
218 struct audit_names *name,
219 enum audit_state *state)
221 int i, j, need_sid = 1;
224 for (i = 0; i < rule->field_count; i++) {
225 struct audit_field *f = &rule->fields[i];
230 result = audit_comparator(tsk->pid, f->op, f->val);
234 result = audit_comparator(ctx->ppid, f->op, f->val);
237 result = audit_comparator(tsk->uid, f->op, f->val);
240 result = audit_comparator(tsk->euid, f->op, f->val);
243 result = audit_comparator(tsk->suid, f->op, f->val);
246 result = audit_comparator(tsk->fsuid, f->op, f->val);
249 result = audit_comparator(tsk->gid, f->op, f->val);
252 result = audit_comparator(tsk->egid, f->op, f->val);
255 result = audit_comparator(tsk->sgid, f->op, f->val);
258 result = audit_comparator(tsk->fsgid, f->op, f->val);
261 result = audit_comparator(tsk->personality, f->op, f->val);
265 result = audit_comparator(ctx->arch, f->op, f->val);
269 if (ctx && ctx->return_valid)
270 result = audit_comparator(ctx->return_code, f->op, f->val);
273 if (ctx && ctx->return_valid) {
275 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
277 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
282 result = audit_comparator(MAJOR(name->dev),
285 for (j = 0; j < ctx->name_count; j++) {
286 if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) {
295 result = audit_comparator(MINOR(name->dev),
298 for (j = 0; j < ctx->name_count; j++) {
299 if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
308 result = (name->ino == f->val);
310 for (j = 0; j < ctx->name_count; j++) {
311 if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
319 if (name && rule->watch->ino != (unsigned long)-1)
320 result = (name->dev == rule->watch->dev &&
321 name->ino == rule->watch->ino);
326 result = audit_comparator(ctx->loginuid, f->op, f->val);
328 case AUDIT_SUBJ_USER:
329 case AUDIT_SUBJ_ROLE:
330 case AUDIT_SUBJ_TYPE:
333 /* NOTE: this may return negative values indicating
334 a temporary error. We simply treat this as a
335 match for now to avoid losing information that
336 may be wanted. An error message will also be
340 selinux_task_ctxid(tsk, &sid);
343 result = selinux_audit_rule_match(sid, f->type,
352 case AUDIT_OBJ_LEV_LOW:
353 case AUDIT_OBJ_LEV_HIGH:
354 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
357 /* Find files that match */
359 result = selinux_audit_rule_match(
360 name->osid, f->type, f->op,
363 for (j = 0; j < ctx->name_count; j++) {
364 if (selinux_audit_rule_match(
373 /* Find ipc objects that match */
375 struct audit_aux_data *aux;
376 for (aux = ctx->aux; aux;
378 if (aux->type == AUDIT_IPC) {
379 struct audit_aux_data_ipcctl *axi = (void *)aux;
380 if (selinux_audit_rule_match(axi->osid, f->type, f->op, f->se_rule, ctx)) {
394 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
396 case AUDIT_FILTERKEY:
397 /* ignore this field for filtering */
406 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
407 switch (rule->action) {
408 case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
409 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
414 /* At process creation time, we can determine if system-call auditing is
415 * completely disabled for this task. Since we only have the task
416 * structure at this point, we can only check uid and gid.
418 static enum audit_state audit_filter_task(struct task_struct *tsk)
420 struct audit_entry *e;
421 enum audit_state state;
424 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
425 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
431 return AUDIT_BUILD_CONTEXT;
434 /* At syscall entry and exit time, this filter is called if the
435 * audit_state is not low enough that auditing cannot take place, but is
436 * also not high enough that we already know we have to write an audit
437 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
439 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
440 struct audit_context *ctx,
441 struct list_head *list)
443 struct audit_entry *e;
444 enum audit_state state;
446 if (audit_pid && tsk->tgid == audit_pid)
447 return AUDIT_DISABLED;
450 if (!list_empty(list)) {
451 int word = AUDIT_WORD(ctx->major);
452 int bit = AUDIT_BIT(ctx->major);
454 list_for_each_entry_rcu(e, list, list) {
455 if ((e->rule.mask[word] & bit) == bit &&
456 audit_filter_rules(tsk, &e->rule, ctx, NULL,
464 return AUDIT_BUILD_CONTEXT;
467 /* At syscall exit time, this filter is called if any audit_names[] have been
468 * collected during syscall processing. We only check rules in sublists at hash
469 * buckets applicable to the inode numbers in audit_names[].
470 * Regarding audit_state, same rules apply as for audit_filter_syscall().
472 enum audit_state audit_filter_inodes(struct task_struct *tsk,
473 struct audit_context *ctx)
476 struct audit_entry *e;
477 enum audit_state state;
479 if (audit_pid && tsk->tgid == audit_pid)
480 return AUDIT_DISABLED;
483 for (i = 0; i < ctx->name_count; i++) {
484 int word = AUDIT_WORD(ctx->major);
485 int bit = AUDIT_BIT(ctx->major);
486 struct audit_names *n = &ctx->names[i];
487 int h = audit_hash_ino((u32)n->ino);
488 struct list_head *list = &audit_inode_hash[h];
490 if (list_empty(list))
493 list_for_each_entry_rcu(e, list, list) {
494 if ((e->rule.mask[word] & bit) == bit &&
495 audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
502 return AUDIT_BUILD_CONTEXT;
505 void audit_set_auditable(struct audit_context *ctx)
510 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
514 struct audit_context *context = tsk->audit_context;
516 if (likely(!context))
518 context->return_valid = return_valid;
519 context->return_code = return_code;
521 if (context->in_syscall && !context->dummy && !context->auditable) {
522 enum audit_state state;
524 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
525 if (state == AUDIT_RECORD_CONTEXT) {
526 context->auditable = 1;
530 state = audit_filter_inodes(tsk, context);
531 if (state == AUDIT_RECORD_CONTEXT)
532 context->auditable = 1;
538 tsk->audit_context = NULL;
542 static inline void audit_free_names(struct audit_context *context)
547 if (context->auditable
548 ||context->put_count + context->ino_count != context->name_count) {
549 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
550 " name_count=%d put_count=%d"
551 " ino_count=%d [NOT freeing]\n",
553 context->serial, context->major, context->in_syscall,
554 context->name_count, context->put_count,
556 for (i = 0; i < context->name_count; i++) {
557 printk(KERN_ERR "names[%d] = %p = %s\n", i,
558 context->names[i].name,
559 context->names[i].name ?: "(null)");
566 context->put_count = 0;
567 context->ino_count = 0;
570 for (i = 0; i < context->name_count; i++) {
571 if (context->names[i].name && context->names[i].name_put)
572 __putname(context->names[i].name);
574 context->name_count = 0;
578 mntput(context->pwdmnt);
580 context->pwdmnt = NULL;
583 static inline void audit_free_aux(struct audit_context *context)
585 struct audit_aux_data *aux;
587 while ((aux = context->aux)) {
588 if (aux->type == AUDIT_AVC_PATH) {
589 struct audit_aux_data_path *axi = (void *)aux;
594 context->aux = aux->next;
599 static inline void audit_zero_context(struct audit_context *context,
600 enum audit_state state)
602 uid_t loginuid = context->loginuid;
604 memset(context, 0, sizeof(*context));
605 context->state = state;
606 context->loginuid = loginuid;
609 static inline struct audit_context *audit_alloc_context(enum audit_state state)
611 struct audit_context *context;
613 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
615 audit_zero_context(context, state);
620 * audit_alloc - allocate an audit context block for a task
623 * Filter on the task information and allocate a per-task audit context
624 * if necessary. Doing so turns on system call auditing for the
625 * specified task. This is called from copy_process, so no lock is
628 int audit_alloc(struct task_struct *tsk)
630 struct audit_context *context;
631 enum audit_state state;
633 if (likely(!audit_enabled))
634 return 0; /* Return if not auditing. */
636 state = audit_filter_task(tsk);
637 if (likely(state == AUDIT_DISABLED))
640 if (!(context = audit_alloc_context(state))) {
641 audit_log_lost("out of memory in audit_alloc");
645 /* Preserve login uid */
646 context->loginuid = -1;
647 if (current->audit_context)
648 context->loginuid = current->audit_context->loginuid;
650 tsk->audit_context = context;
651 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
655 static inline void audit_free_context(struct audit_context *context)
657 struct audit_context *previous;
661 previous = context->previous;
662 if (previous || (count && count < 10)) {
664 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
665 " freeing multiple contexts (%d)\n",
666 context->serial, context->major,
667 context->name_count, count);
669 audit_free_names(context);
670 audit_free_aux(context);
671 kfree(context->filterkey);
676 printk(KERN_ERR "audit: freed %d contexts\n", count);
679 static void audit_log_task_context(struct audit_buffer *ab)
684 len = security_getprocattr(current, "current", NULL, 0);
691 ctx = kmalloc(len, GFP_KERNEL);
695 len = security_getprocattr(current, "current", ctx, len);
699 audit_log_format(ab, " subj=%s", ctx);
704 audit_panic("error in audit_log_task_context");
708 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
710 char name[sizeof(tsk->comm)];
711 struct mm_struct *mm = tsk->mm;
712 struct vm_area_struct *vma;
716 get_task_comm(name, tsk);
717 audit_log_format(ab, " comm=");
718 audit_log_untrustedstring(ab, name);
721 down_read(&mm->mmap_sem);
724 if ((vma->vm_flags & VM_EXECUTABLE) &&
726 audit_log_d_path(ab, "exe=",
727 vma->vm_file->f_dentry,
728 vma->vm_file->f_vfsmnt);
733 up_read(&mm->mmap_sem);
735 audit_log_task_context(ab);
738 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
740 int i, call_panic = 0;
741 struct audit_buffer *ab;
742 struct audit_aux_data *aux;
746 context->pid = tsk->pid;
747 context->ppid = sys_getppid(); /* sic. tsk == current in all cases */
748 context->uid = tsk->uid;
749 context->gid = tsk->gid;
750 context->euid = tsk->euid;
751 context->suid = tsk->suid;
752 context->fsuid = tsk->fsuid;
753 context->egid = tsk->egid;
754 context->sgid = tsk->sgid;
755 context->fsgid = tsk->fsgid;
756 context->personality = tsk->personality;
758 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
760 return; /* audit_panic has been called */
761 audit_log_format(ab, "arch=%x syscall=%d",
762 context->arch, context->major);
763 if (context->personality != PER_LINUX)
764 audit_log_format(ab, " per=%lx", context->personality);
765 if (context->return_valid)
766 audit_log_format(ab, " success=%s exit=%ld",
767 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
768 context->return_code);
769 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
770 tty = tsk->signal->tty->name;
774 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
775 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
776 " euid=%u suid=%u fsuid=%u"
777 " egid=%u sgid=%u fsgid=%u tty=%s",
788 context->euid, context->suid, context->fsuid,
789 context->egid, context->sgid, context->fsgid, tty);
790 audit_log_task_info(ab, tsk);
791 if (context->filterkey) {
792 audit_log_format(ab, " key=");
793 audit_log_untrustedstring(ab, context->filterkey);
795 audit_log_format(ab, " key=(null)");
798 for (aux = context->aux; aux; aux = aux->next) {
800 ab = audit_log_start(context, GFP_KERNEL, aux->type);
802 continue; /* audit_panic has been called */
805 case AUDIT_MQ_OPEN: {
806 struct audit_aux_data_mq_open *axi = (void *)aux;
808 "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
809 "mq_msgsize=%ld mq_curmsgs=%ld",
810 axi->oflag, axi->mode, axi->attr.mq_flags,
811 axi->attr.mq_maxmsg, axi->attr.mq_msgsize,
812 axi->attr.mq_curmsgs);
815 case AUDIT_MQ_SENDRECV: {
816 struct audit_aux_data_mq_sendrecv *axi = (void *)aux;
818 "mqdes=%d msg_len=%zd msg_prio=%u "
819 "abs_timeout_sec=%ld abs_timeout_nsec=%ld",
820 axi->mqdes, axi->msg_len, axi->msg_prio,
821 axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec);
824 case AUDIT_MQ_NOTIFY: {
825 struct audit_aux_data_mq_notify *axi = (void *)aux;
827 "mqdes=%d sigev_signo=%d",
829 axi->notification.sigev_signo);
832 case AUDIT_MQ_GETSETATTR: {
833 struct audit_aux_data_mq_getsetattr *axi = (void *)aux;
835 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
838 axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg,
839 axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs);
843 struct audit_aux_data_ipcctl *axi = (void *)aux;
845 "ouid=%u ogid=%u mode=%x",
846 axi->uid, axi->gid, axi->mode);
847 if (axi->osid != 0) {
850 if (selinux_ctxid_to_string(
851 axi->osid, &ctx, &len)) {
852 audit_log_format(ab, " osid=%u",
856 audit_log_format(ab, " obj=%s", ctx);
861 case AUDIT_IPC_SET_PERM: {
862 struct audit_aux_data_ipcctl *axi = (void *)aux;
864 "qbytes=%lx ouid=%u ogid=%u mode=%x",
865 axi->qbytes, axi->uid, axi->gid, axi->mode);
869 struct audit_aux_data_execve *axi = (void *)aux;
872 for (i = 0, p = axi->mem; i < axi->argc; i++) {
873 audit_log_format(ab, "a%d=", i);
874 p = audit_log_untrustedstring(ab, p);
875 audit_log_format(ab, "\n");
879 case AUDIT_SOCKETCALL: {
881 struct audit_aux_data_socketcall *axs = (void *)aux;
882 audit_log_format(ab, "nargs=%d", axs->nargs);
883 for (i=0; i<axs->nargs; i++)
884 audit_log_format(ab, " a%d=%lx", i, axs->args[i]);
887 case AUDIT_SOCKADDR: {
888 struct audit_aux_data_sockaddr *axs = (void *)aux;
890 audit_log_format(ab, "saddr=");
891 audit_log_hex(ab, axs->a, axs->len);
894 case AUDIT_AVC_PATH: {
895 struct audit_aux_data_path *axi = (void *)aux;
896 audit_log_d_path(ab, "path=", axi->dentry, axi->mnt);
903 if (context->pwd && context->pwdmnt) {
904 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
906 audit_log_d_path(ab, "cwd=", context->pwd, context->pwdmnt);
910 for (i = 0; i < context->name_count; i++) {
911 struct audit_names *n = &context->names[i];
913 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
915 continue; /* audit_panic has been called */
917 audit_log_format(ab, "item=%d", i);
920 switch(n->name_len) {
921 case AUDIT_NAME_FULL:
922 /* log the full path */
923 audit_log_format(ab, " name=");
924 audit_log_untrustedstring(ab, n->name);
927 /* name was specified as a relative path and the
928 * directory component is the cwd */
929 audit_log_d_path(ab, " name=", context->pwd,
933 /* log the name's directory component */
934 audit_log_format(ab, " name=");
935 audit_log_n_untrustedstring(ab, n->name_len,
939 audit_log_format(ab, " name=(null)");
941 if (n->ino != (unsigned long)-1) {
942 audit_log_format(ab, " inode=%lu"
943 " dev=%02x:%02x mode=%#o"
944 " ouid=%u ogid=%u rdev=%02x:%02x",
957 if (selinux_ctxid_to_string(
958 n->osid, &ctx, &len)) {
959 audit_log_format(ab, " osid=%u", n->osid);
962 audit_log_format(ab, " obj=%s", ctx);
969 audit_panic("error converting sid to string");
973 * audit_free - free a per-task audit context
974 * @tsk: task whose audit context block to free
976 * Called from copy_process and do_exit
978 void audit_free(struct task_struct *tsk)
980 struct audit_context *context;
982 context = audit_get_context(tsk, 0, 0);
983 if (likely(!context))
986 /* Check for system calls that do not go through the exit
987 * function (e.g., exit_group), then free context block.
988 * We use GFP_ATOMIC here because we might be doing this
989 * in the context of the idle thread */
990 /* that can happen only if we are called from do_exit() */
991 if (context->in_syscall && context->auditable)
992 audit_log_exit(context, tsk);
994 audit_free_context(context);
998 * audit_syscall_entry - fill in an audit record at syscall entry
999 * @tsk: task being audited
1000 * @arch: architecture type
1001 * @major: major syscall type (function)
1002 * @a1: additional syscall register 1
1003 * @a2: additional syscall register 2
1004 * @a3: additional syscall register 3
1005 * @a4: additional syscall register 4
1007 * Fill in audit context at syscall entry. This only happens if the
1008 * audit context was created when the task was created and the state or
1009 * filters demand the audit context be built. If the state from the
1010 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1011 * then the record will be written at syscall exit time (otherwise, it
1012 * will only be written if another part of the kernel requests that it
1015 void audit_syscall_entry(int arch, int major,
1016 unsigned long a1, unsigned long a2,
1017 unsigned long a3, unsigned long a4)
1019 struct task_struct *tsk = current;
1020 struct audit_context *context = tsk->audit_context;
1021 enum audit_state state;
1026 * This happens only on certain architectures that make system
1027 * calls in kernel_thread via the entry.S interface, instead of
1028 * with direct calls. (If you are porting to a new
1029 * architecture, hitting this condition can indicate that you
1030 * got the _exit/_leave calls backward in entry.S.)
1034 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S)
1036 * This also happens with vm86 emulation in a non-nested manner
1037 * (entries without exits), so this case must be caught.
1039 if (context->in_syscall) {
1040 struct audit_context *newctx;
1044 "audit(:%d) pid=%d in syscall=%d;"
1045 " entering syscall=%d\n",
1046 context->serial, tsk->pid, context->major, major);
1048 newctx = audit_alloc_context(context->state);
1050 newctx->previous = context;
1052 tsk->audit_context = newctx;
1054 /* If we can't alloc a new context, the best we
1055 * can do is to leak memory (any pending putname
1056 * will be lost). The only other alternative is
1057 * to abandon auditing. */
1058 audit_zero_context(context, context->state);
1061 BUG_ON(context->in_syscall || context->name_count);
1066 context->arch = arch;
1067 context->major = major;
1068 context->argv[0] = a1;
1069 context->argv[1] = a2;
1070 context->argv[2] = a3;
1071 context->argv[3] = a4;
1073 state = context->state;
1074 context->dummy = !audit_n_rules;
1075 if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT))
1076 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1077 if (likely(state == AUDIT_DISABLED))
1080 context->serial = 0;
1081 context->ctime = CURRENT_TIME;
1082 context->in_syscall = 1;
1083 context->auditable = !!(state == AUDIT_RECORD_CONTEXT);
1087 * audit_syscall_exit - deallocate audit context after a system call
1088 * @tsk: task being audited
1089 * @valid: success/failure flag
1090 * @return_code: syscall return value
1092 * Tear down after system call. If the audit context has been marked as
1093 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1094 * filtering, or because some other part of the kernel write an audit
1095 * message), then write out the syscall information. In call cases,
1096 * free the names stored from getname().
1098 void audit_syscall_exit(int valid, long return_code)
1100 struct task_struct *tsk = current;
1101 struct audit_context *context;
1103 context = audit_get_context(tsk, valid, return_code);
1105 if (likely(!context))
1108 if (context->in_syscall && context->auditable)
1109 audit_log_exit(context, tsk);
1111 context->in_syscall = 0;
1112 context->auditable = 0;
1114 if (context->previous) {
1115 struct audit_context *new_context = context->previous;
1116 context->previous = NULL;
1117 audit_free_context(context);
1118 tsk->audit_context = new_context;
1120 audit_free_names(context);
1121 audit_free_aux(context);
1122 kfree(context->filterkey);
1123 context->filterkey = NULL;
1124 tsk->audit_context = context;
1129 * audit_getname - add a name to the list
1130 * @name: name to add
1132 * Add a name to the list of audit names for this context.
1133 * Called from fs/namei.c:getname().
1135 void __audit_getname(const char *name)
1137 struct audit_context *context = current->audit_context;
1139 if (IS_ERR(name) || !name)
1142 if (!context->in_syscall) {
1143 #if AUDIT_DEBUG == 2
1144 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1145 __FILE__, __LINE__, context->serial, name);
1150 BUG_ON(context->name_count >= AUDIT_NAMES);
1151 context->names[context->name_count].name = name;
1152 context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1153 context->names[context->name_count].name_put = 1;
1154 context->names[context->name_count].ino = (unsigned long)-1;
1155 ++context->name_count;
1156 if (!context->pwd) {
1157 read_lock(¤t->fs->lock);
1158 context->pwd = dget(current->fs->pwd);
1159 context->pwdmnt = mntget(current->fs->pwdmnt);
1160 read_unlock(¤t->fs->lock);
1165 /* audit_putname - intercept a putname request
1166 * @name: name to intercept and delay for putname
1168 * If we have stored the name from getname in the audit context,
1169 * then we delay the putname until syscall exit.
1170 * Called from include/linux/fs.h:putname().
1172 void audit_putname(const char *name)
1174 struct audit_context *context = current->audit_context;
1177 if (!context->in_syscall) {
1178 #if AUDIT_DEBUG == 2
1179 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1180 __FILE__, __LINE__, context->serial, name);
1181 if (context->name_count) {
1183 for (i = 0; i < context->name_count; i++)
1184 printk(KERN_ERR "name[%d] = %p = %s\n", i,
1185 context->names[i].name,
1186 context->names[i].name ?: "(null)");
1193 ++context->put_count;
1194 if (context->put_count > context->name_count) {
1195 printk(KERN_ERR "%s:%d(:%d): major=%d"
1196 " in_syscall=%d putname(%p) name_count=%d"
1199 context->serial, context->major,
1200 context->in_syscall, name, context->name_count,
1201 context->put_count);
1208 /* Copy inode data into an audit_names. */
1209 static void audit_copy_inode(struct audit_names *name, const struct inode *inode)
1211 name->ino = inode->i_ino;
1212 name->dev = inode->i_sb->s_dev;
1213 name->mode = inode->i_mode;
1214 name->uid = inode->i_uid;
1215 name->gid = inode->i_gid;
1216 name->rdev = inode->i_rdev;
1217 selinux_get_inode_sid(inode, &name->osid);
1221 * audit_inode - store the inode and device from a lookup
1222 * @name: name being audited
1223 * @inode: inode being audited
1225 * Called from fs/namei.c:path_lookup().
1227 void __audit_inode(const char *name, const struct inode *inode)
1230 struct audit_context *context = current->audit_context;
1232 if (!context->in_syscall)
1234 if (context->name_count
1235 && context->names[context->name_count-1].name
1236 && context->names[context->name_count-1].name == name)
1237 idx = context->name_count - 1;
1238 else if (context->name_count > 1
1239 && context->names[context->name_count-2].name
1240 && context->names[context->name_count-2].name == name)
1241 idx = context->name_count - 2;
1243 /* FIXME: how much do we care about inodes that have no
1244 * associated name? */
1245 if (context->name_count >= AUDIT_NAMES - AUDIT_NAMES_RESERVED)
1247 idx = context->name_count++;
1248 context->names[idx].name = NULL;
1250 ++context->ino_count;
1253 audit_copy_inode(&context->names[idx], inode);
1257 * audit_inode_child - collect inode info for created/removed objects
1258 * @dname: inode's dentry name
1259 * @inode: inode being audited
1260 * @parent: inode of dentry parent
1262 * For syscalls that create or remove filesystem objects, audit_inode
1263 * can only collect information for the filesystem object's parent.
1264 * This call updates the audit context with the child's information.
1265 * Syscalls that create a new filesystem object must be hooked after
1266 * the object is created. Syscalls that remove a filesystem object
1267 * must be hooked prior, in order to capture the target inode during
1268 * unsuccessful attempts.
1270 void __audit_inode_child(const char *dname, const struct inode *inode,
1271 const struct inode *parent)
1274 struct audit_context *context = current->audit_context;
1275 const char *found_name = NULL;
1278 if (!context->in_syscall)
1281 /* determine matching parent */
1283 goto update_context;
1284 for (idx = 0; idx < context->name_count; idx++)
1285 if (context->names[idx].ino == parent->i_ino) {
1286 const char *name = context->names[idx].name;
1291 if (audit_compare_dname_path(dname, name, &dirlen) == 0) {
1292 context->names[idx].name_len = dirlen;
1299 idx = context->name_count++;
1301 context->ino_count++;
1303 /* Re-use the name belonging to the slot for a matching parent directory.
1304 * All names for this context are relinquished in audit_free_names() */
1305 context->names[idx].name = found_name;
1306 context->names[idx].name_len = AUDIT_NAME_FULL;
1307 context->names[idx].name_put = 0; /* don't call __putname() */
1310 context->names[idx].ino = (unsigned long)-1;
1312 audit_copy_inode(&context->names[idx], inode);
1314 /* A parent was not found in audit_names, so copy the inode data for the
1315 * provided parent. */
1317 idx = context->name_count++;
1319 context->ino_count++;
1321 audit_copy_inode(&context->names[idx], parent);
1326 * audit_inode_update - update inode info for last collected name
1327 * @inode: inode being audited
1329 * When open() is called on an existing object with the O_CREAT flag, the inode
1330 * data audit initially collects is incorrect. This additional hook ensures
1331 * audit has the inode data for the actual object to be opened.
1333 void __audit_inode_update(const struct inode *inode)
1335 struct audit_context *context = current->audit_context;
1338 if (!context->in_syscall || !inode)
1341 if (context->name_count == 0) {
1342 context->name_count++;
1344 context->ino_count++;
1347 idx = context->name_count - 1;
1349 audit_copy_inode(&context->names[idx], inode);
1353 * auditsc_get_stamp - get local copies of audit_context values
1354 * @ctx: audit_context for the task
1355 * @t: timespec to store time recorded in the audit_context
1356 * @serial: serial value that is recorded in the audit_context
1358 * Also sets the context as auditable.
1360 void auditsc_get_stamp(struct audit_context *ctx,
1361 struct timespec *t, unsigned int *serial)
1364 ctx->serial = audit_serial();
1365 t->tv_sec = ctx->ctime.tv_sec;
1366 t->tv_nsec = ctx->ctime.tv_nsec;
1367 *serial = ctx->serial;
1372 * audit_set_loginuid - set a task's audit_context loginuid
1373 * @task: task whose audit context is being modified
1374 * @loginuid: loginuid value
1378 * Called (set) from fs/proc/base.c::proc_loginuid_write().
1380 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
1382 struct audit_context *context = task->audit_context;
1385 /* Only log if audit is enabled */
1386 if (context->in_syscall) {
1387 struct audit_buffer *ab;
1389 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
1391 audit_log_format(ab, "login pid=%d uid=%u "
1392 "old auid=%u new auid=%u",
1393 task->pid, task->uid,
1394 context->loginuid, loginuid);
1398 context->loginuid = loginuid;
1404 * audit_get_loginuid - get the loginuid for an audit_context
1405 * @ctx: the audit_context
1407 * Returns the context's loginuid or -1 if @ctx is NULL.
1409 uid_t audit_get_loginuid(struct audit_context *ctx)
1411 return ctx ? ctx->loginuid : -1;
1415 * __audit_mq_open - record audit data for a POSIX MQ open
1418 * @u_attr: queue attributes
1420 * Returns 0 for success or NULL context or < 0 on error.
1422 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr)
1424 struct audit_aux_data_mq_open *ax;
1425 struct audit_context *context = current->audit_context;
1430 if (likely(!context))
1433 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1437 if (u_attr != NULL) {
1438 if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) {
1443 memset(&ax->attr, 0, sizeof(ax->attr));
1448 ax->d.type = AUDIT_MQ_OPEN;
1449 ax->d.next = context->aux;
1450 context->aux = (void *)ax;
1455 * __audit_mq_timedsend - record audit data for a POSIX MQ timed send
1456 * @mqdes: MQ descriptor
1457 * @msg_len: Message length
1458 * @msg_prio: Message priority
1459 * @u_abs_timeout: Message timeout in absolute time
1461 * Returns 0 for success or NULL context or < 0 on error.
1463 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
1464 const struct timespec __user *u_abs_timeout)
1466 struct audit_aux_data_mq_sendrecv *ax;
1467 struct audit_context *context = current->audit_context;
1472 if (likely(!context))
1475 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1479 if (u_abs_timeout != NULL) {
1480 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
1485 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
1488 ax->msg_len = msg_len;
1489 ax->msg_prio = msg_prio;
1491 ax->d.type = AUDIT_MQ_SENDRECV;
1492 ax->d.next = context->aux;
1493 context->aux = (void *)ax;
1498 * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive
1499 * @mqdes: MQ descriptor
1500 * @msg_len: Message length
1501 * @u_msg_prio: Message priority
1502 * @u_abs_timeout: Message timeout in absolute time
1504 * Returns 0 for success or NULL context or < 0 on error.
1506 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len,
1507 unsigned int __user *u_msg_prio,
1508 const struct timespec __user *u_abs_timeout)
1510 struct audit_aux_data_mq_sendrecv *ax;
1511 struct audit_context *context = current->audit_context;
1516 if (likely(!context))
1519 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1523 if (u_msg_prio != NULL) {
1524 if (get_user(ax->msg_prio, u_msg_prio)) {
1531 if (u_abs_timeout != NULL) {
1532 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
1537 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
1540 ax->msg_len = msg_len;
1542 ax->d.type = AUDIT_MQ_SENDRECV;
1543 ax->d.next = context->aux;
1544 context->aux = (void *)ax;
1549 * __audit_mq_notify - record audit data for a POSIX MQ notify
1550 * @mqdes: MQ descriptor
1551 * @u_notification: Notification event
1553 * Returns 0 for success or NULL context or < 0 on error.
1556 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification)
1558 struct audit_aux_data_mq_notify *ax;
1559 struct audit_context *context = current->audit_context;
1564 if (likely(!context))
1567 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1571 if (u_notification != NULL) {
1572 if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) {
1577 memset(&ax->notification, 0, sizeof(ax->notification));
1581 ax->d.type = AUDIT_MQ_NOTIFY;
1582 ax->d.next = context->aux;
1583 context->aux = (void *)ax;
1588 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
1589 * @mqdes: MQ descriptor
1592 * Returns 0 for success or NULL context or < 0 on error.
1594 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
1596 struct audit_aux_data_mq_getsetattr *ax;
1597 struct audit_context *context = current->audit_context;
1602 if (likely(!context))
1605 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1610 ax->mqstat = *mqstat;
1612 ax->d.type = AUDIT_MQ_GETSETATTR;
1613 ax->d.next = context->aux;
1614 context->aux = (void *)ax;
1619 * audit_ipc_obj - record audit data for ipc object
1620 * @ipcp: ipc permissions
1622 * Returns 0 for success or NULL context or < 0 on error.
1624 int __audit_ipc_obj(struct kern_ipc_perm *ipcp)
1626 struct audit_aux_data_ipcctl *ax;
1627 struct audit_context *context = current->audit_context;
1629 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1633 ax->uid = ipcp->uid;
1634 ax->gid = ipcp->gid;
1635 ax->mode = ipcp->mode;
1636 selinux_get_ipc_sid(ipcp, &ax->osid);
1638 ax->d.type = AUDIT_IPC;
1639 ax->d.next = context->aux;
1640 context->aux = (void *)ax;
1645 * audit_ipc_set_perm - record audit data for new ipc permissions
1646 * @qbytes: msgq bytes
1647 * @uid: msgq user id
1648 * @gid: msgq group id
1649 * @mode: msgq mode (permissions)
1651 * Returns 0 for success or NULL context or < 0 on error.
1653 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
1655 struct audit_aux_data_ipcctl *ax;
1656 struct audit_context *context = current->audit_context;
1658 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1662 ax->qbytes = qbytes;
1667 ax->d.type = AUDIT_IPC_SET_PERM;
1668 ax->d.next = context->aux;
1669 context->aux = (void *)ax;
1673 int audit_bprm(struct linux_binprm *bprm)
1675 struct audit_aux_data_execve *ax;
1676 struct audit_context *context = current->audit_context;
1677 unsigned long p, next;
1680 if (likely(!audit_enabled || !context || context->dummy))
1683 ax = kmalloc(sizeof(*ax) + PAGE_SIZE * MAX_ARG_PAGES - bprm->p,
1688 ax->argc = bprm->argc;
1689 ax->envc = bprm->envc;
1690 for (p = bprm->p, to = ax->mem; p < MAX_ARG_PAGES*PAGE_SIZE; p = next) {
1691 struct page *page = bprm->page[p / PAGE_SIZE];
1692 void *kaddr = kmap(page);
1693 next = (p + PAGE_SIZE) & ~(PAGE_SIZE - 1);
1694 memcpy(to, kaddr + (p & (PAGE_SIZE - 1)), next - p);
1699 ax->d.type = AUDIT_EXECVE;
1700 ax->d.next = context->aux;
1701 context->aux = (void *)ax;
1707 * audit_socketcall - record audit data for sys_socketcall
1708 * @nargs: number of args
1711 * Returns 0 for success or NULL context or < 0 on error.
1713 int audit_socketcall(int nargs, unsigned long *args)
1715 struct audit_aux_data_socketcall *ax;
1716 struct audit_context *context = current->audit_context;
1718 if (likely(!context || context->dummy))
1721 ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL);
1726 memcpy(ax->args, args, nargs * sizeof(unsigned long));
1728 ax->d.type = AUDIT_SOCKETCALL;
1729 ax->d.next = context->aux;
1730 context->aux = (void *)ax;
1735 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
1736 * @len: data length in user space
1737 * @a: data address in kernel space
1739 * Returns 0 for success or NULL context or < 0 on error.
1741 int audit_sockaddr(int len, void *a)
1743 struct audit_aux_data_sockaddr *ax;
1744 struct audit_context *context = current->audit_context;
1746 if (likely(!context || context->dummy))
1749 ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL);
1754 memcpy(ax->a, a, len);
1756 ax->d.type = AUDIT_SOCKADDR;
1757 ax->d.next = context->aux;
1758 context->aux = (void *)ax;
1763 * audit_avc_path - record the granting or denial of permissions
1764 * @dentry: dentry to record
1765 * @mnt: mnt to record
1767 * Returns 0 for success or NULL context or < 0 on error.
1769 * Called from security/selinux/avc.c::avc_audit()
1771 int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt)
1773 struct audit_aux_data_path *ax;
1774 struct audit_context *context = current->audit_context;
1776 if (likely(!context))
1779 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1783 ax->dentry = dget(dentry);
1784 ax->mnt = mntget(mnt);
1786 ax->d.type = AUDIT_AVC_PATH;
1787 ax->d.next = context->aux;
1788 context->aux = (void *)ax;
1793 * audit_signal_info - record signal info for shutting down audit subsystem
1794 * @sig: signal value
1795 * @t: task being signaled
1797 * If the audit subsystem is being terminated, record the task (pid)
1798 * and uid that is doing that.
1800 void __audit_signal_info(int sig, struct task_struct *t)
1802 extern pid_t audit_sig_pid;
1803 extern uid_t audit_sig_uid;
1804 extern u32 audit_sig_sid;
1806 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1) {
1807 struct task_struct *tsk = current;
1808 struct audit_context *ctx = tsk->audit_context;
1809 audit_sig_pid = tsk->pid;
1811 audit_sig_uid = ctx->loginuid;
1813 audit_sig_uid = tsk->uid;
1814 selinux_get_task_sid(tsk, &audit_sig_sid);