2 * Copyright (c) 1999-2009 Apple Inc.
3 * Copyright (c) 2005 Robert N. M. Watson
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of Apple Inc. ("Apple") nor the names of
15 * its contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR
22 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
34 #include <sys/param.h>
35 #include <sys/fcntl.h>
36 #include <sys/filedesc.h>
37 #include <sys/libkern.h>
38 #include <sys/malloc.h>
39 #include <sys/mount.h>
41 #include <sys/rwlock.h>
44 #include <sys/syscall.h>
45 #include <sys/sysctl.h>
46 #include <sys/sysent.h>
47 #include <sys/vnode.h>
49 #include <bsm/audit.h>
50 #include <bsm/audit_kevents.h>
51 #include <security/audit/audit.h>
52 #include <security/audit/audit_private.h>
55 * Hash table functions for the audit event number to event class mask
58 #define EVCLASSMAP_HASH_TABLE_SIZE 251
62 LIST_ENTRY(evclass_elem) entry;
65 LIST_HEAD(, evclass_elem) head;
68 static MALLOC_DEFINE(M_AUDITEVCLASS, "audit_evclass", "Audit event class");
69 static struct rwlock evclass_lock;
70 static struct evclass_list evclass_hash[EVCLASSMAP_HASH_TABLE_SIZE];
72 #define EVCLASS_LOCK_INIT() rw_init(&evclass_lock, "evclass_lock")
73 #define EVCLASS_RLOCK() rw_rlock(&evclass_lock)
74 #define EVCLASS_RUNLOCK() rw_runlock(&evclass_lock)
75 #define EVCLASS_WLOCK() rw_wlock(&evclass_lock)
76 #define EVCLASS_WUNLOCK() rw_wunlock(&evclass_lock)
79 * Look up the class for an audit event in the class mapping table.
82 au_event_class(au_event_t event)
84 struct evclass_list *evcl;
85 struct evclass_elem *evc;
89 evcl = &evclass_hash[event % EVCLASSMAP_HASH_TABLE_SIZE];
91 LIST_FOREACH(evc, &evcl->head, entry) {
92 if (evc->event == event) {
103 * Insert a event to class mapping. If the event already exists in the
104 * mapping, then replace the mapping with the new one.
106 * XXX There is currently no constraints placed on the number of mappings.
107 * May want to either limit to a number, or in terms of memory usage.
110 au_evclassmap_insert(au_event_t event, au_class_t class)
112 struct evclass_list *evcl;
113 struct evclass_elem *evc, *evc_new;
116 * Pessimistically, always allocate storage before acquiring mutex.
117 * Free if there is already a mapping for this event.
119 evc_new = malloc(sizeof(*evc), M_AUDITEVCLASS, M_WAITOK);
122 evcl = &evclass_hash[event % EVCLASSMAP_HASH_TABLE_SIZE];
123 LIST_FOREACH(evc, &evcl->head, entry) {
124 if (evc->event == event) {
127 free(evc_new, M_AUDITEVCLASS);
134 LIST_INSERT_HEAD(&evcl->head, evc, entry);
139 au_evclassmap_init(void)
144 for (i = 0; i < EVCLASSMAP_HASH_TABLE_SIZE; i++)
145 LIST_INIT(&evclass_hash[i].head);
148 * Set up the initial event to class mapping for system calls.
150 * XXXRW: Really, this should walk all possible audit events, not all
151 * native ABI system calls, as there may be audit events reachable
152 * only through non-native system calls. It also seems a shame to
153 * frob the mutex this early.
155 for (i = 0; i < SYS_MAXSYSCALL; i++) {
156 if (sysent[i].sy_auevent != AUE_NULL)
157 au_evclassmap_insert(sysent[i].sy_auevent, 0);
162 * Check whether an event is aditable by comparing the mask of classes this
163 * event is part of against the given mask.
166 au_preselect(au_event_t event, au_class_t class, au_mask_t *mask_p, int sorf)
168 au_class_t effmask = 0;
174 * Perform the actual check of the masks against the event.
176 if (sorf & AU_PRS_SUCCESS)
177 effmask |= (mask_p->am_success & class);
179 if (sorf & AU_PRS_FAILURE)
180 effmask |= (mask_p->am_failure & class);
189 * Convert sysctl names and present arguments to events.
192 audit_ctlname_to_sysctlevent(int name[], uint64_t valid_arg)
195 /* can't parse it - so return the worst case */
196 if ((valid_arg & (ARG_CTLNAME | ARG_LEN)) != (ARG_CTLNAME | ARG_LEN))
200 /* non-admin "lookups" treat them special */
210 case KERN_JOB_CONTROL:
214 return (AUE_SYSCTL_NONADMIN);
216 /* only treat the changeable controls as admin */
220 case KERN_MAXPROCPERUID:
221 case KERN_MAXFILESPERPROC:
229 case KERN_NISDOMAINNAME:
230 case KERN_UPDATEINTERVAL:
235 case KERN_PS_STRINGS:
237 case KERN_LOGSIGEXIT:
240 return ((valid_arg & ARG_VALUE) ?
241 AUE_SYSCTL : AUE_SYSCTL_NONADMIN);
250 * Convert an open flags specifier into a specific type of open event for
254 audit_flags_and_error_to_openevent(int oflags, int error)
259 * Need to check only those flags we care about.
261 oflags = oflags & (O_RDONLY | O_CREAT | O_TRUNC | O_RDWR | O_WRONLY);
264 * These checks determine what flags are on with the condition that
265 * ONLY that combination is on, and no other flags are on.
272 case (O_RDONLY | O_CREAT):
273 aevent = AUE_OPEN_RC;
276 case (O_RDONLY | O_CREAT | O_TRUNC):
277 aevent = AUE_OPEN_RTC;
280 case (O_RDONLY | O_TRUNC):
281 aevent = AUE_OPEN_RT;
285 aevent = AUE_OPEN_RW;
288 case (O_RDWR | O_CREAT):
289 aevent = AUE_OPEN_RWC;
292 case (O_RDWR | O_CREAT | O_TRUNC):
293 aevent = AUE_OPEN_RWTC;
296 case (O_RDWR | O_TRUNC):
297 aevent = AUE_OPEN_RWT;
304 case (O_WRONLY | O_CREAT):
305 aevent = AUE_OPEN_WC;
308 case (O_WRONLY | O_CREAT | O_TRUNC):
309 aevent = AUE_OPEN_WTC;
312 case (O_WRONLY | O_TRUNC):
313 aevent = AUE_OPEN_WT;
323 * Convert chatty errors to better matching events. Failures to
324 * find a file are really just attribute events -- so recast them as
327 * XXXAUDIT: Solaris defines that AUE_OPEN will never be returned, it
328 * is just a placeholder. However, in Darwin we return that in
329 * preference to other events. For now, comment this out as we don't
330 * have a BSM conversion routine for AUE_OPEN.
347 * Convert a MSGCTL command to a specific event.
350 audit_msgctl_to_event(int cmd)
355 return (AUE_MSGCTL_RMID);
358 return (AUE_MSGCTL_SET);
361 return (AUE_MSGCTL_STAT);
364 /* We will audit a bad command. */
370 * Convert a SEMCTL command to a specific event.
373 audit_semctl_to_event(int cmd)
378 return (AUE_SEMCTL_GETALL);
381 return (AUE_SEMCTL_GETNCNT);
384 return (AUE_SEMCTL_GETPID);
387 return (AUE_SEMCTL_GETVAL);
390 return (AUE_SEMCTL_GETZCNT);
393 return (AUE_SEMCTL_RMID);
396 return (AUE_SEMCTL_SET);
399 return (AUE_SEMCTL_SETALL);
402 return (AUE_SEMCTL_SETVAL);
405 return (AUE_SEMCTL_STAT);
408 /* We will audit a bad command. */
414 * Convert a command for the auditon() system call to a audit event.
417 auditon_command_event(int cmd)
422 return (AUE_AUDITON_GPOLICY);
425 return (AUE_AUDITON_SPOLICY);
428 return (AUE_AUDITON_GETKMASK);
431 return (AUE_AUDITON_SETKMASK);
434 return (AUE_AUDITON_GQCTRL);
437 return (AUE_AUDITON_SQCTRL);
440 return (AUE_AUDITON_GETCWD);
443 return (AUE_AUDITON_GETCAR);
446 return (AUE_AUDITON_GETSTAT);
449 return (AUE_AUDITON_SETSTAT);
452 return (AUE_AUDITON_SETUMASK);
455 return (AUE_AUDITON_SETSMASK);
458 return (AUE_AUDITON_GETCOND);
461 return (AUE_AUDITON_SETCOND);
464 return (AUE_AUDITON_GETCLASS);
467 return (AUE_AUDITON_SETCLASS);
473 case A_GETPINFO_ADDR:
477 return (AUE_AUDITON); /* No special record */
482 * Create a canonical path from given path by prefixing either the root
483 * directory, or the current working directory. If the process working
484 * directory is NULL, we could use 'rootvnode' to obtain the root directory,
485 * but this results in a volfs name written to the audit log. So we will
486 * leave the filename starting with '/' in the audit log in this case.
489 audit_canon_path(struct thread *td, char *path, char *cpath)
491 struct vnode *cvnp, *rvnp;
492 char *rbuf, *fbuf, *copy;
493 struct filedesc *fdp;
497 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "%s: at %s:%d",
498 __func__, __FILE__, __LINE__);
502 fdp = td->td_proc->p_fd;
505 * Make sure that we handle the chroot(2) case. If there is an
506 * alternate root directory, prepend it to the audited pathname.
508 if (fdp->fd_rdir != NULL && fdp->fd_rdir != rootvnode) {
513 * If the supplied path is relative, make sure we capture the current
514 * working directory so we can prepend it to the supplied relative
521 cwir = (fdp->fd_rdir == fdp->fd_cdir);
522 FILEDESC_SUNLOCK(fdp);
524 * NB: We require that the supplied array be at least MAXPATHLEN bytes
525 * long. If this is not the case, then we can run into serious trouble.
527 (void) sbuf_new(&sbf, cpath, MAXPATHLEN, SBUF_FIXEDLEN);
529 * Strip leading forward slashes.
534 * Make sure we handle chroot(2) and prepend the global path to these
537 * NB: vn_fullpath(9) on FreeBSD is less reliable than vn_getpath(9)
538 * on Darwin. As a result, this may need some additional attention
542 error = vn_fullpath_global(td, rvnp, &rbuf, &fbuf);
550 (void) sbuf_cat(&sbf, rbuf);
554 error = vn_fullpath(td, cvnp, &rbuf, &fbuf);
560 (void) sbuf_cat(&sbf, rbuf);
563 if (cwir == 0 || (cwir != 0 && cvnp == NULL))
564 (void) sbuf_putc(&sbf, '/');
566 * Now that we have processed any alternate root and relative path
567 * names, add the supplied pathname.
569 (void) sbuf_cat(&sbf, copy);
571 * One or more of the previous sbuf operations could have resulted in
572 * the supplied buffer being overflowed. Check to see if this is the
575 if (sbuf_overflowed(&sbf) != 0) {