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)
78 struct aue_open_event {
83 static const struct aue_open_event aue_open[] = {
84 { O_RDONLY, AUE_OPEN_R },
85 { (O_RDONLY | O_CREAT), AUE_OPEN_RC },
86 { (O_RDONLY | O_CREAT | O_TRUNC), AUE_OPEN_RTC },
87 { (O_RDONLY | O_TRUNC), AUE_OPEN_RT },
88 { O_RDWR, AUE_OPEN_RW },
89 { (O_RDWR | O_CREAT), AUE_OPEN_RWC },
90 { (O_RDWR | O_CREAT | O_TRUNC), AUE_OPEN_RWTC },
91 { (O_RDWR | O_TRUNC), AUE_OPEN_RWT },
92 { O_WRONLY, AUE_OPEN_W },
93 { (O_WRONLY | O_CREAT), AUE_OPEN_WC },
94 { (O_WRONLY | O_CREAT | O_TRUNC), AUE_OPEN_WTC },
95 { (O_WRONLY | O_TRUNC), AUE_OPEN_WT },
97 static const int aue_open_count = sizeof(aue_open) / sizeof(aue_open[0]);
99 static const struct aue_open_event aue_openat[] = {
100 { O_RDONLY, AUE_OPENAT_R },
101 { (O_RDONLY | O_CREAT), AUE_OPENAT_RC },
102 { (O_RDONLY | O_CREAT | O_TRUNC), AUE_OPENAT_RTC },
103 { (O_RDONLY | O_TRUNC), AUE_OPENAT_RT },
104 { O_RDWR, AUE_OPENAT_RW },
105 { (O_RDWR | O_CREAT), AUE_OPENAT_RWC },
106 { (O_RDWR | O_CREAT | O_TRUNC), AUE_OPENAT_RWTC },
107 { (O_RDWR | O_TRUNC), AUE_OPENAT_RWT },
108 { O_WRONLY, AUE_OPENAT_W },
109 { (O_WRONLY | O_CREAT), AUE_OPENAT_WC },
110 { (O_WRONLY | O_CREAT | O_TRUNC), AUE_OPENAT_WTC },
111 { (O_WRONLY | O_TRUNC), AUE_OPENAT_WT },
113 static const int aue_openat_count = sizeof(aue_openat) / sizeof(aue_openat[0]);
116 * Look up the class for an audit event in the class mapping table.
119 au_event_class(au_event_t event)
121 struct evclass_list *evcl;
122 struct evclass_elem *evc;
126 evcl = &evclass_hash[event % EVCLASSMAP_HASH_TABLE_SIZE];
128 LIST_FOREACH(evc, &evcl->head, entry) {
129 if (evc->event == event) {
140 * Insert a event to class mapping. If the event already exists in the
141 * mapping, then replace the mapping with the new one.
143 * XXX There is currently no constraints placed on the number of mappings.
144 * May want to either limit to a number, or in terms of memory usage.
147 au_evclassmap_insert(au_event_t event, au_class_t class)
149 struct evclass_list *evcl;
150 struct evclass_elem *evc, *evc_new;
153 * Pessimistically, always allocate storage before acquiring mutex.
154 * Free if there is already a mapping for this event.
156 evc_new = malloc(sizeof(*evc), M_AUDITEVCLASS, M_WAITOK);
159 evcl = &evclass_hash[event % EVCLASSMAP_HASH_TABLE_SIZE];
160 LIST_FOREACH(evc, &evcl->head, entry) {
161 if (evc->event == event) {
164 free(evc_new, M_AUDITEVCLASS);
171 LIST_INSERT_HEAD(&evcl->head, evc, entry);
176 au_evclassmap_init(void)
181 for (i = 0; i < EVCLASSMAP_HASH_TABLE_SIZE; i++)
182 LIST_INIT(&evclass_hash[i].head);
185 * Set up the initial event to class mapping for system calls.
187 * XXXRW: Really, this should walk all possible audit events, not all
188 * native ABI system calls, as there may be audit events reachable
189 * only through non-native system calls. It also seems a shame to
190 * frob the mutex this early.
192 for (i = 0; i < SYS_MAXSYSCALL; i++) {
193 if (sysent[i].sy_auevent != AUE_NULL)
194 au_evclassmap_insert(sysent[i].sy_auevent, 0);
199 * Check whether an event is aditable by comparing the mask of classes this
200 * event is part of against the given mask.
203 au_preselect(au_event_t event, au_class_t class, au_mask_t *mask_p, int sorf)
205 au_class_t effmask = 0;
211 * Perform the actual check of the masks against the event.
213 if (sorf & AU_PRS_SUCCESS)
214 effmask |= (mask_p->am_success & class);
216 if (sorf & AU_PRS_FAILURE)
217 effmask |= (mask_p->am_failure & class);
226 * Convert sysctl names and present arguments to events.
229 audit_ctlname_to_sysctlevent(int name[], uint64_t valid_arg)
232 /* can't parse it - so return the worst case */
233 if ((valid_arg & (ARG_CTLNAME | ARG_LEN)) != (ARG_CTLNAME | ARG_LEN))
237 /* non-admin "lookups" treat them special */
247 case KERN_JOB_CONTROL:
251 return (AUE_SYSCTL_NONADMIN);
253 /* only treat the changeable controls as admin */
257 case KERN_MAXPROCPERUID:
258 case KERN_MAXFILESPERPROC:
266 case KERN_NISDOMAINNAME:
267 case KERN_UPDATEINTERVAL:
272 case KERN_PS_STRINGS:
274 case KERN_LOGSIGEXIT:
277 return ((valid_arg & ARG_VALUE) ?
278 AUE_SYSCTL : AUE_SYSCTL_NONADMIN);
287 * Convert an open flags specifier into a specific type of open event for
291 audit_flags_and_error_to_openevent(int oflags, int error)
296 * Need to check only those flags we care about.
298 oflags = oflags & (O_RDONLY | O_CREAT | O_TRUNC | O_RDWR | O_WRONLY);
299 for (i = 0; i < aue_open_count; i++) {
300 if (aue_open[i].aoe_flags == oflags)
301 return (aue_open[i].aoe_event);
307 audit_flags_and_error_to_openatevent(int oflags, int error)
312 * Need to check only those flags we care about.
314 oflags = oflags & (O_RDONLY | O_CREAT | O_TRUNC | O_RDWR | O_WRONLY);
315 for (i = 0; i < aue_openat_count; i++) {
316 if (aue_openat[i].aoe_flags == oflags)
317 return (aue_openat[i].aoe_event);
323 * Convert a MSGCTL command to a specific event.
326 audit_msgctl_to_event(int cmd)
331 return (AUE_MSGCTL_RMID);
334 return (AUE_MSGCTL_SET);
337 return (AUE_MSGCTL_STAT);
340 /* We will audit a bad command. */
346 * Convert a SEMCTL command to a specific event.
349 audit_semctl_to_event(int cmd)
354 return (AUE_SEMCTL_GETALL);
357 return (AUE_SEMCTL_GETNCNT);
360 return (AUE_SEMCTL_GETPID);
363 return (AUE_SEMCTL_GETVAL);
366 return (AUE_SEMCTL_GETZCNT);
369 return (AUE_SEMCTL_RMID);
372 return (AUE_SEMCTL_SET);
375 return (AUE_SEMCTL_SETALL);
378 return (AUE_SEMCTL_SETVAL);
381 return (AUE_SEMCTL_STAT);
384 /* We will audit a bad command. */
390 * Convert a command for the auditon() system call to a audit event.
393 auditon_command_event(int cmd)
398 return (AUE_AUDITON_GPOLICY);
401 return (AUE_AUDITON_SPOLICY);
404 return (AUE_AUDITON_GETKMASK);
407 return (AUE_AUDITON_SETKMASK);
410 return (AUE_AUDITON_GQCTRL);
413 return (AUE_AUDITON_SQCTRL);
416 return (AUE_AUDITON_GETCWD);
419 return (AUE_AUDITON_GETCAR);
422 return (AUE_AUDITON_GETSTAT);
425 return (AUE_AUDITON_SETSTAT);
428 return (AUE_AUDITON_SETUMASK);
431 return (AUE_AUDITON_SETSMASK);
434 return (AUE_AUDITON_GETCOND);
437 return (AUE_AUDITON_SETCOND);
440 return (AUE_AUDITON_GETCLASS);
443 return (AUE_AUDITON_SETCLASS);
449 case A_GETPINFO_ADDR:
453 return (AUE_AUDITON); /* No special record */
458 * Create a canonical path from given path by prefixing either the root
459 * directory, or the current working directory. If the process working
460 * directory is NULL, we could use 'rootvnode' to obtain the root directory,
461 * but this results in a volfs name written to the audit log. So we will
462 * leave the filename starting with '/' in the audit log in this case.
465 audit_canon_path(struct thread *td, char *path, char *cpath)
467 struct vnode *cvnp, *rvnp;
468 char *rbuf, *fbuf, *copy;
469 struct filedesc *fdp;
473 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "%s: at %s:%d",
474 __func__, __FILE__, __LINE__);
478 fdp = td->td_proc->p_fd;
481 * Make sure that we handle the chroot(2) case. If there is an
482 * alternate root directory, prepend it to the audited pathname.
484 if (fdp->fd_rdir != NULL && fdp->fd_rdir != rootvnode) {
489 * If the supplied path is relative, make sure we capture the current
490 * working directory so we can prepend it to the supplied relative
497 cwir = (fdp->fd_rdir == fdp->fd_cdir);
498 FILEDESC_SUNLOCK(fdp);
500 * NB: We require that the supplied array be at least MAXPATHLEN bytes
501 * long. If this is not the case, then we can run into serious trouble.
503 (void) sbuf_new(&sbf, cpath, MAXPATHLEN, SBUF_FIXEDLEN);
505 * Strip leading forward slashes.
510 * Make sure we handle chroot(2) and prepend the global path to these
513 * NB: vn_fullpath(9) on FreeBSD is less reliable than vn_getpath(9)
514 * on Darwin. As a result, this may need some additional attention
518 error = vn_fullpath_global(td, rvnp, &rbuf, &fbuf);
526 (void) sbuf_cat(&sbf, rbuf);
530 error = vn_fullpath(td, cvnp, &rbuf, &fbuf);
536 (void) sbuf_cat(&sbf, rbuf);
539 if (cwir == 0 || (cwir != 0 && cvnp == NULL))
540 (void) sbuf_putc(&sbf, '/');
542 * Now that we have processed any alternate root and relative path
543 * names, add the supplied pathname.
545 (void) sbuf_cat(&sbf, copy);
547 * One or more of the previous sbuf operations could have resulted in
548 * the supplied buffer being overflowed. Check to see if this is the
551 if (sbuf_overflowed(&sbf) != 0) {