xref: /freebsd/sys/security/audit/audit_syscalls.c (revision 4928135658a9d0eaee37003df6137ab363fcb0b4)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1999-2009 Apple Inc.
5  * Copyright (c) 2016 Robert N. M. Watson
6  * All rights reserved.
7  *
8  * Portions of this software were developed by BAE Systems, the University of
9  * Cambridge Computer Laboratory, and Memorial University under DARPA/AFRL
10  * contract FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent
11  * Computing (TC) research program.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1.  Redistributions of source code must retain the above copyright
17  *     notice, this list of conditions and the following disclaimer.
18  * 2.  Redistributions in binary form must reproduce the above copyright
19  *     notice, this list of conditions and the following disclaimer in the
20  *     documentation and/or other materials provided with the distribution.
21  * 3.  Neither the name of Apple Inc. ("Apple") nor the names of
22  *     its contributors may be used to endorse or promote products derived
23  *     from this software without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR
29  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
33  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
34  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include <sys/param.h>
42 #include <sys/mount.h>
43 #include <sys/namei.h>
44 #include <sys/priv.h>
45 #include <sys/proc.h>
46 #include <sys/sysproto.h>
47 #include <sys/systm.h>
48 #include <sys/vnode.h>
49 #include <sys/jail.h>
50 
51 #include <bsm/audit.h>
52 #include <bsm/audit_kevents.h>
53 
54 #include <security/audit/audit.h>
55 #include <security/audit/audit_private.h>
56 #include <security/mac/mac_framework.h>
57 
58 #ifdef AUDIT
59 
60 /*
61  * System call to allow a user space application to submit a BSM audit record
62  * to the kernel for inclusion in the audit log.  This function does little
63  * verification on the audit record that is submitted.
64  *
65  * XXXAUDIT: Audit preselection for user records does not currently work,
66  * since we pre-select only based on the AUE_audit event type, not the event
67  * type submitted as part of the user audit data.
68  */
69 /* ARGSUSED */
70 int
71 sys_audit(struct thread *td, struct audit_args *uap)
72 {
73 	int error;
74 	void * rec;
75 	struct kaudit_record *ar;
76 
77 	if (jailed(td->td_ucred))
78 		return (ENOSYS);
79 	error = priv_check(td, PRIV_AUDIT_SUBMIT);
80 	if (error)
81 		return (error);
82 
83 	if ((uap->length <= 0) || (uap->length > audit_qctrl.aq_bufsz))
84 		return (EINVAL);
85 
86 	ar = currecord();
87 
88 	/*
89 	 * If there's no current audit record (audit() itself not audited)
90 	 * commit the user audit record.
91 	 */
92 	if (ar == NULL) {
93 
94 		/*
95 		 * This is not very efficient; we're required to allocate a
96 		 * complete kernel audit record just so the user record can
97 		 * tag along.
98 		 *
99 		 * XXXAUDIT: Maybe AUE_AUDIT in the system call context and
100 		 * special pre-select handling?
101 		 */
102 		td->td_ar = audit_new(AUE_NULL, td);
103 		if (td->td_ar == NULL)
104 			return (ENOTSUP);
105 		td->td_pflags |= TDP_AUDITREC;
106 		ar = td->td_ar;
107 	}
108 
109 	if (uap->length > MAX_AUDIT_RECORD_SIZE)
110 		return (EINVAL);
111 
112 	rec = malloc(uap->length, M_AUDITDATA, M_WAITOK);
113 
114 	error = copyin(uap->record, rec, uap->length);
115 	if (error)
116 		goto free_out;
117 
118 	/* Verify the record. */
119 	if (bsm_rec_verify(rec) == 0) {
120 		error = EINVAL;
121 		goto free_out;
122 	}
123 
124 #ifdef MAC
125 	error = mac_system_check_audit(td->td_ucred, rec, uap->length);
126 	if (error)
127 		goto free_out;
128 #endif
129 
130 	/*
131 	 * Attach the user audit record to the kernel audit record.  Because
132 	 * this system call is an auditable event, we will write the user
133 	 * record along with the record for this audit event.
134 	 *
135 	 * XXXAUDIT: KASSERT appropriate starting values of k_udata, k_ulen,
136 	 * k_ar_commit & AR_COMMIT_USER?
137 	 */
138 	ar->k_udata = rec;
139 	ar->k_ulen  = uap->length;
140 	ar->k_ar_commit |= AR_COMMIT_USER;
141 
142 	/*
143 	 * Currently we assume that all preselection has been performed in
144 	 * userspace.  We unconditionally set these masks so that the records
145 	 * get committed both to the trail and pipe.  In the future we will
146 	 * want to setup kernel based preselection.
147 	 */
148 	ar->k_ar_commit |= (AR_PRESELECT_USER_TRAIL | AR_PRESELECT_USER_PIPE);
149 	return (0);
150 
151 free_out:
152 	/*
153 	 * audit_syscall_exit() will free the audit record on the thread even
154 	 * if we allocated it above.
155 	 */
156 	free(rec, M_AUDITDATA);
157 	return (error);
158 }
159 
160 /*
161  *  System call to manipulate auditing.
162  */
163 /* ARGSUSED */
164 int
165 sys_auditon(struct thread *td, struct auditon_args *uap)
166 {
167 	struct ucred *cred, *newcred, *oldcred;
168 	int error;
169 	union auditon_udata udata;
170 	struct proc *tp;
171 
172 	if (jailed(td->td_ucred))
173 		return (ENOSYS);
174 	AUDIT_ARG_CMD(uap->cmd);
175 
176 #ifdef MAC
177 	error = mac_system_check_auditon(td->td_ucred, uap->cmd);
178 	if (error)
179 		return (error);
180 #endif
181 
182 	error = priv_check(td, PRIV_AUDIT_CONTROL);
183 	if (error)
184 		return (error);
185 
186 	if ((uap->length <= 0) || (uap->length > sizeof(union auditon_udata)))
187 		return (EINVAL);
188 
189 	memset((void *)&udata, 0, sizeof(udata));
190 
191 	/*
192 	 * Some of the GET commands use the arguments too.
193 	 */
194 	switch (uap->cmd) {
195 	case A_SETPOLICY:
196 	case A_OLDSETPOLICY:
197 	case A_SETKMASK:
198 	case A_SETQCTRL:
199 	case A_OLDSETQCTRL:
200 	case A_SETSTAT:
201 	case A_SETUMASK:
202 	case A_SETSMASK:
203 	case A_SETCOND:
204 	case A_OLDSETCOND:
205 	case A_SETCLASS:
206 	case A_SETEVENT:
207 	case A_SETPMASK:
208 	case A_SETFSIZE:
209 	case A_SETKAUDIT:
210 	case A_GETCLASS:
211 	case A_GETEVENT:
212 	case A_GETPINFO:
213 	case A_GETPINFO_ADDR:
214 	case A_SENDTRIGGER:
215 		error = copyin(uap->data, (void *)&udata, uap->length);
216 		if (error)
217 			return (error);
218 		AUDIT_ARG_AUDITON(&udata);
219 		break;
220 	}
221 
222 	/*
223 	 * XXXAUDIT: Locking?
224 	 */
225 	switch (uap->cmd) {
226 	case A_OLDGETPOLICY:
227 	case A_GETPOLICY:
228 		if (uap->length == sizeof(udata.au_policy64)) {
229 			if (!audit_fail_stop)
230 				udata.au_policy64 |= AUDIT_CNT;
231 			if (audit_panic_on_write_fail)
232 				udata.au_policy64 |= AUDIT_AHLT;
233 			if (audit_argv)
234 				udata.au_policy64 |= AUDIT_ARGV;
235 			if (audit_arge)
236 				udata.au_policy64 |= AUDIT_ARGE;
237 			break;
238 		}
239 		if (uap->length != sizeof(udata.au_policy))
240 			return (EINVAL);
241 		if (!audit_fail_stop)
242 			udata.au_policy |= AUDIT_CNT;
243 		if (audit_panic_on_write_fail)
244 			udata.au_policy |= AUDIT_AHLT;
245 		if (audit_argv)
246 			udata.au_policy |= AUDIT_ARGV;
247 		if (audit_arge)
248 			udata.au_policy |= AUDIT_ARGE;
249 		break;
250 
251 	case A_OLDSETPOLICY:
252 	case A_SETPOLICY:
253 		if (uap->length == sizeof(udata.au_policy64)) {
254 			if (udata.au_policy & (~AUDIT_CNT|AUDIT_AHLT|
255 			    AUDIT_ARGV|AUDIT_ARGE))
256 				return (EINVAL);
257 			audit_fail_stop = ((udata.au_policy64 & AUDIT_CNT) ==
258 			    0);
259 			audit_panic_on_write_fail = (udata.au_policy64 &
260 			    AUDIT_AHLT);
261 			audit_argv = (udata.au_policy64 & AUDIT_ARGV);
262 			audit_arge = (udata.au_policy64 & AUDIT_ARGE);
263 			break;
264 		}
265 		if (uap->length != sizeof(udata.au_policy))
266 			return (EINVAL);
267 		if (udata.au_policy & ~(AUDIT_CNT|AUDIT_AHLT|AUDIT_ARGV|
268 		    AUDIT_ARGE))
269 			return (EINVAL);
270 		/*
271 		 * XXX - Need to wake up waiters if the policy relaxes?
272 		 */
273 		audit_fail_stop = ((udata.au_policy & AUDIT_CNT) == 0);
274 		audit_panic_on_write_fail = (udata.au_policy & AUDIT_AHLT);
275 		audit_argv = (udata.au_policy & AUDIT_ARGV);
276 		audit_arge = (udata.au_policy & AUDIT_ARGE);
277 		break;
278 
279 	case A_GETKMASK:
280 		if (uap->length != sizeof(udata.au_mask))
281 			return (EINVAL);
282 		udata.au_mask = audit_nae_mask;
283 		break;
284 
285 	case A_SETKMASK:
286 		if (uap->length != sizeof(udata.au_mask))
287 			return (EINVAL);
288 		audit_nae_mask = udata.au_mask;
289 		break;
290 
291 	case A_OLDGETQCTRL:
292 	case A_GETQCTRL:
293 		if (uap->length == sizeof(udata.au_qctrl64)) {
294 			udata.au_qctrl64.aq64_hiwater =
295 			    (u_int64_t)audit_qctrl.aq_hiwater;
296 			udata.au_qctrl64.aq64_lowater =
297 			    (u_int64_t)audit_qctrl.aq_lowater;
298 			udata.au_qctrl64.aq64_bufsz =
299 			    (u_int64_t)audit_qctrl.aq_bufsz;
300 			udata.au_qctrl64.aq64_minfree =
301 			    (u_int64_t)audit_qctrl.aq_minfree;
302 			break;
303 		}
304 		if (uap->length != sizeof(udata.au_qctrl))
305 			return (EINVAL);
306 		udata.au_qctrl = audit_qctrl;
307 		break;
308 
309 	case A_OLDSETQCTRL:
310 	case A_SETQCTRL:
311 		if (uap->length == sizeof(udata.au_qctrl64)) {
312 			/* NB: aq64_minfree is unsigned unlike aq_minfree. */
313 			if ((udata.au_qctrl64.aq64_hiwater > AQ_MAXHIGH) ||
314 			    (udata.au_qctrl64.aq64_lowater >=
315 			    udata.au_qctrl.aq_hiwater) ||
316 			    (udata.au_qctrl64.aq64_bufsz > AQ_MAXBUFSZ) ||
317 			    (udata.au_qctrl64.aq64_minfree > 100))
318 				return (EINVAL);
319 			audit_qctrl.aq_hiwater =
320 			    (int)udata.au_qctrl64.aq64_hiwater;
321 			audit_qctrl.aq_lowater =
322 			    (int)udata.au_qctrl64.aq64_lowater;
323 			audit_qctrl.aq_bufsz =
324 			    (int)udata.au_qctrl64.aq64_bufsz;
325 			audit_qctrl.aq_minfree =
326 			    (int)udata.au_qctrl64.aq64_minfree;
327 			audit_qctrl.aq_delay = -1;	/* Not used. */
328 			break;
329 		}
330 		if (uap->length != sizeof(udata.au_qctrl))
331 			return (EINVAL);
332 		if ((udata.au_qctrl.aq_hiwater > AQ_MAXHIGH) ||
333 		    (udata.au_qctrl.aq_lowater >= udata.au_qctrl.aq_hiwater) ||
334 		    (udata.au_qctrl.aq_bufsz > AQ_MAXBUFSZ) ||
335 		    (udata.au_qctrl.aq_minfree < 0) ||
336 		    (udata.au_qctrl.aq_minfree > 100))
337 			return (EINVAL);
338 
339 		audit_qctrl = udata.au_qctrl;
340 		/* XXX The queue delay value isn't used with the kernel. */
341 		audit_qctrl.aq_delay = -1;
342 		break;
343 
344 	case A_GETCWD:
345 		return (ENOSYS);
346 		break;
347 
348 	case A_GETCAR:
349 		return (ENOSYS);
350 		break;
351 
352 	case A_GETSTAT:
353 		return (ENOSYS);
354 		break;
355 
356 	case A_SETSTAT:
357 		return (ENOSYS);
358 		break;
359 
360 	case A_SETUMASK:
361 		return (ENOSYS);
362 		break;
363 
364 	case A_SETSMASK:
365 		return (ENOSYS);
366 		break;
367 
368 	case A_OLDGETCOND:
369 	case A_GETCOND:
370 		if (uap->length == sizeof(udata.au_cond64)) {
371 			if (audit_enabled && !audit_suspended)
372 				udata.au_cond64 = AUC_AUDITING;
373 			else
374 				udata.au_cond64 = AUC_NOAUDIT;
375 			break;
376 		}
377 		if (uap->length != sizeof(udata.au_cond))
378 			return (EINVAL);
379 		if (audit_enabled && !audit_suspended)
380 			udata.au_cond = AUC_AUDITING;
381 		else
382 			udata.au_cond = AUC_NOAUDIT;
383 		break;
384 
385 	case A_OLDSETCOND:
386 	case A_SETCOND:
387 		if (uap->length == sizeof(udata.au_cond64)) {
388 			if (udata.au_cond64 == AUC_NOAUDIT)
389 				audit_suspended = 1;
390 			if (udata.au_cond64 == AUC_AUDITING)
391 				audit_suspended = 0;
392 			if (udata.au_cond64 == AUC_DISABLED) {
393 				audit_suspended = 1;
394 				audit_shutdown(NULL, 0);
395 			}
396 			break;
397 		}
398 		if (uap->length != sizeof(udata.au_cond))
399 			return (EINVAL);
400 		if (udata.au_cond == AUC_NOAUDIT)
401 			audit_suspended = 1;
402 		if (udata.au_cond == AUC_AUDITING)
403 			audit_suspended = 0;
404 		if (udata.au_cond == AUC_DISABLED) {
405 			audit_suspended = 1;
406 			audit_shutdown(NULL, 0);
407 		}
408 		break;
409 
410 	case A_GETCLASS:
411 		if (uap->length != sizeof(udata.au_evclass))
412 			return (EINVAL);
413 		udata.au_evclass.ec_class = au_event_class(
414 		    udata.au_evclass.ec_number);
415 		break;
416 
417 	case A_GETEVENT:
418 		if (uap->length != sizeof(udata.au_evname))
419 			return (EINVAL);
420 		error = au_event_name(udata.au_evname.en_number,
421 		    udata.au_evname.en_name);
422 		if (error != 0)
423 			return (error);
424 		break;
425 
426 	case A_SETCLASS:
427 		if (uap->length != sizeof(udata.au_evclass))
428 			return (EINVAL);
429 		au_evclassmap_insert(udata.au_evclass.ec_number,
430 		    udata.au_evclass.ec_class);
431 		break;
432 
433 	case A_SETEVENT:
434 		if (uap->length != sizeof(udata.au_evname))
435 			return (EINVAL);
436 
437 		/* Ensure nul termination from userspace. */
438 		udata.au_evname.en_name[sizeof(udata.au_evname.en_name) - 1]
439 		    = 0;
440 		au_evnamemap_insert(udata.au_evname.en_number,
441 		    udata.au_evname.en_name);
442 		break;
443 
444 	case A_GETPINFO:
445 		if (uap->length != sizeof(udata.au_aupinfo))
446 			return (EINVAL);
447 		if (udata.au_aupinfo.ap_pid < 1)
448 			return (ESRCH);
449 		if ((tp = pfind(udata.au_aupinfo.ap_pid)) == NULL)
450 			return (ESRCH);
451 		if ((error = p_cansee(td, tp)) != 0) {
452 			PROC_UNLOCK(tp);
453 			return (error);
454 		}
455 		cred = tp->p_ucred;
456 		if (cred->cr_audit.ai_termid.at_type == AU_IPv6) {
457 			PROC_UNLOCK(tp);
458 			return (EINVAL);
459 		}
460 		udata.au_aupinfo.ap_auid = cred->cr_audit.ai_auid;
461 		udata.au_aupinfo.ap_mask.am_success =
462 		    cred->cr_audit.ai_mask.am_success;
463 		udata.au_aupinfo.ap_mask.am_failure =
464 		    cred->cr_audit.ai_mask.am_failure;
465 		udata.au_aupinfo.ap_termid.machine =
466 		    cred->cr_audit.ai_termid.at_addr[0];
467 		udata.au_aupinfo.ap_termid.port =
468 		    (dev_t)cred->cr_audit.ai_termid.at_port;
469 		udata.au_aupinfo.ap_asid = cred->cr_audit.ai_asid;
470 		PROC_UNLOCK(tp);
471 		break;
472 
473 	case A_SETPMASK:
474 		if (uap->length != sizeof(udata.au_aupinfo))
475 			return (EINVAL);
476 		if (udata.au_aupinfo.ap_pid < 1)
477 			return (ESRCH);
478 		newcred = crget();
479 		if ((tp = pfind(udata.au_aupinfo.ap_pid)) == NULL) {
480 			crfree(newcred);
481 			return (ESRCH);
482 		}
483 		if ((error = p_cansee(td, tp)) != 0) {
484 			PROC_UNLOCK(tp);
485 			crfree(newcred);
486 			return (error);
487 		}
488 		oldcred = tp->p_ucred;
489 		crcopy(newcred, oldcred);
490 		newcred->cr_audit.ai_mask.am_success =
491 		    udata.au_aupinfo.ap_mask.am_success;
492 		newcred->cr_audit.ai_mask.am_failure =
493 		    udata.au_aupinfo.ap_mask.am_failure;
494 		proc_set_cred(tp, newcred);
495 		PROC_UNLOCK(tp);
496 		crfree(oldcred);
497 		break;
498 
499 	case A_SETFSIZE:
500 		if (uap->length != sizeof(udata.au_fstat))
501 			return (EINVAL);
502 		if ((udata.au_fstat.af_filesz != 0) &&
503 		   (udata.au_fstat.af_filesz < MIN_AUDIT_FILE_SIZE))
504 			return (EINVAL);
505 		audit_fstat.af_filesz = udata.au_fstat.af_filesz;
506 		break;
507 
508 	case A_GETFSIZE:
509 		if (uap->length != sizeof(udata.au_fstat))
510 			return (EINVAL);
511 		udata.au_fstat.af_filesz = audit_fstat.af_filesz;
512 		udata.au_fstat.af_currsz = audit_fstat.af_currsz;
513 		break;
514 
515 	case A_GETPINFO_ADDR:
516 		if (uap->length != sizeof(udata.au_aupinfo_addr))
517 			return (EINVAL);
518 		if (udata.au_aupinfo_addr.ap_pid < 1)
519 			return (ESRCH);
520 		if ((tp = pfind(udata.au_aupinfo_addr.ap_pid)) == NULL)
521 			return (ESRCH);
522 		cred = tp->p_ucred;
523 		udata.au_aupinfo_addr.ap_auid = cred->cr_audit.ai_auid;
524 		udata.au_aupinfo_addr.ap_mask.am_success =
525 		    cred->cr_audit.ai_mask.am_success;
526 		udata.au_aupinfo_addr.ap_mask.am_failure =
527 		    cred->cr_audit.ai_mask.am_failure;
528 		udata.au_aupinfo_addr.ap_termid = cred->cr_audit.ai_termid;
529 		udata.au_aupinfo_addr.ap_asid = cred->cr_audit.ai_asid;
530 		PROC_UNLOCK(tp);
531 		break;
532 
533 	case A_GETKAUDIT:
534 		if (uap->length != sizeof(udata.au_kau_info))
535 			return (EINVAL);
536 		audit_get_kinfo(&udata.au_kau_info);
537 		break;
538 
539 	case A_SETKAUDIT:
540 		if (uap->length != sizeof(udata.au_kau_info))
541 			return (EINVAL);
542 		if (udata.au_kau_info.ai_termid.at_type != AU_IPv4 &&
543 		    udata.au_kau_info.ai_termid.at_type != AU_IPv6)
544 			return (EINVAL);
545 		audit_set_kinfo(&udata.au_kau_info);
546 		break;
547 
548 	case A_SENDTRIGGER:
549 		if (uap->length != sizeof(udata.au_trigger))
550 			return (EINVAL);
551 		if ((udata.au_trigger < AUDIT_TRIGGER_MIN) ||
552 		    (udata.au_trigger > AUDIT_TRIGGER_MAX))
553 			return (EINVAL);
554 		return (audit_send_trigger(udata.au_trigger));
555 
556 	default:
557 		return (EINVAL);
558 	}
559 
560 	/*
561 	 * Copy data back to userspace for the GET comands.
562 	 */
563 	switch (uap->cmd) {
564 	case A_GETPOLICY:
565 	case A_OLDGETPOLICY:
566 	case A_GETKMASK:
567 	case A_GETQCTRL:
568 	case A_OLDGETQCTRL:
569 	case A_GETCWD:
570 	case A_GETCAR:
571 	case A_GETSTAT:
572 	case A_GETCOND:
573 	case A_OLDGETCOND:
574 	case A_GETCLASS:
575 	case A_GETPINFO:
576 	case A_GETFSIZE:
577 	case A_GETPINFO_ADDR:
578 	case A_GETKAUDIT:
579 		error = copyout((void *)&udata, uap->data, uap->length);
580 		if (error)
581 			return (error);
582 		break;
583 	}
584 
585 	return (0);
586 }
587 
588 /*
589  * System calls to manage the user audit information.
590  */
591 /* ARGSUSED */
592 int
593 sys_getauid(struct thread *td, struct getauid_args *uap)
594 {
595 	int error;
596 
597 	if (jailed(td->td_ucred))
598 		return (ENOSYS);
599 	error = priv_check(td, PRIV_AUDIT_GETAUDIT);
600 	if (error)
601 		return (error);
602 	return (copyout(&td->td_ucred->cr_audit.ai_auid, uap->auid,
603 	    sizeof(td->td_ucred->cr_audit.ai_auid)));
604 }
605 
606 /* ARGSUSED */
607 int
608 sys_setauid(struct thread *td, struct setauid_args *uap)
609 {
610 	struct ucred *newcred, *oldcred;
611 	au_id_t id;
612 	int error;
613 
614 	if (jailed(td->td_ucred))
615 		return (ENOSYS);
616 	error = copyin(uap->auid, &id, sizeof(id));
617 	if (error)
618 		return (error);
619 	audit_arg_auid(id);
620 	newcred = crget();
621 	PROC_LOCK(td->td_proc);
622 	oldcred = td->td_proc->p_ucred;
623 	crcopy(newcred, oldcred);
624 #ifdef MAC
625 	error = mac_cred_check_setauid(oldcred, id);
626 	if (error)
627 		goto fail;
628 #endif
629 	error = priv_check_cred(oldcred, PRIV_AUDIT_SETAUDIT, 0);
630 	if (error)
631 		goto fail;
632 	newcred->cr_audit.ai_auid = id;
633 	proc_set_cred(td->td_proc, newcred);
634 	PROC_UNLOCK(td->td_proc);
635 	crfree(oldcred);
636 	return (0);
637 fail:
638 	PROC_UNLOCK(td->td_proc);
639 	crfree(newcred);
640 	return (error);
641 }
642 
643 /*
644  * System calls to get and set process audit information.
645  */
646 /* ARGSUSED */
647 int
648 sys_getaudit(struct thread *td, struct getaudit_args *uap)
649 {
650 	struct auditinfo ai;
651 	struct ucred *cred;
652 	int error;
653 
654 	cred = td->td_ucred;
655 	if (jailed(cred))
656 		return (ENOSYS);
657 	error = priv_check(td, PRIV_AUDIT_GETAUDIT);
658 	if (error)
659 		return (error);
660 	if (cred->cr_audit.ai_termid.at_type == AU_IPv6)
661 		return (E2BIG);
662 	bzero(&ai, sizeof(ai));
663 	ai.ai_auid = cred->cr_audit.ai_auid;
664 	ai.ai_mask = cred->cr_audit.ai_mask;
665 	ai.ai_asid = cred->cr_audit.ai_asid;
666 	ai.ai_termid.machine = cred->cr_audit.ai_termid.at_addr[0];
667 	ai.ai_termid.port = cred->cr_audit.ai_termid.at_port;
668 	return (copyout(&ai, uap->auditinfo, sizeof(ai)));
669 }
670 
671 /* ARGSUSED */
672 int
673 sys_setaudit(struct thread *td, struct setaudit_args *uap)
674 {
675 	struct ucred *newcred, *oldcred;
676 	struct auditinfo ai;
677 	int error;
678 
679 	if (jailed(td->td_ucred))
680 		return (ENOSYS);
681 	error = copyin(uap->auditinfo, &ai, sizeof(ai));
682 	if (error)
683 		return (error);
684 	audit_arg_auditinfo(&ai);
685 	newcred = crget();
686 	PROC_LOCK(td->td_proc);
687 	oldcred = td->td_proc->p_ucred;
688 	crcopy(newcred, oldcred);
689 #ifdef MAC
690 	error = mac_cred_check_setaudit(oldcred, &ai);
691 	if (error)
692 		goto fail;
693 #endif
694 	error = priv_check_cred(oldcred, PRIV_AUDIT_SETAUDIT, 0);
695 	if (error)
696 		goto fail;
697 	bzero(&newcred->cr_audit, sizeof(newcred->cr_audit));
698 	newcred->cr_audit.ai_auid = ai.ai_auid;
699 	newcred->cr_audit.ai_mask = ai.ai_mask;
700 	newcred->cr_audit.ai_asid = ai.ai_asid;
701 	newcred->cr_audit.ai_termid.at_addr[0] = ai.ai_termid.machine;
702 	newcred->cr_audit.ai_termid.at_port = ai.ai_termid.port;
703 	newcred->cr_audit.ai_termid.at_type = AU_IPv4;
704 	proc_set_cred(td->td_proc, newcred);
705 	PROC_UNLOCK(td->td_proc);
706 	crfree(oldcred);
707 	return (0);
708 fail:
709 	PROC_UNLOCK(td->td_proc);
710 	crfree(newcred);
711 	return (error);
712 }
713 
714 /* ARGSUSED */
715 int
716 sys_getaudit_addr(struct thread *td, struct getaudit_addr_args *uap)
717 {
718 	int error;
719 
720 	if (jailed(td->td_ucred))
721 		return (ENOSYS);
722 	if (uap->length < sizeof(*uap->auditinfo_addr))
723 		return (EOVERFLOW);
724 	error = priv_check(td, PRIV_AUDIT_GETAUDIT);
725 	if (error)
726 		return (error);
727 	return (copyout(&td->td_ucred->cr_audit, uap->auditinfo_addr,
728 	    sizeof(*uap->auditinfo_addr)));
729 }
730 
731 /* ARGSUSED */
732 int
733 sys_setaudit_addr(struct thread *td, struct setaudit_addr_args *uap)
734 {
735 	struct ucred *newcred, *oldcred;
736 	struct auditinfo_addr aia;
737 	int error;
738 
739 	if (jailed(td->td_ucred))
740 		return (ENOSYS);
741 	error = copyin(uap->auditinfo_addr, &aia, sizeof(aia));
742 	if (error)
743 		return (error);
744 	audit_arg_auditinfo_addr(&aia);
745 	if (aia.ai_termid.at_type != AU_IPv6 &&
746 	    aia.ai_termid.at_type != AU_IPv4)
747 		return (EINVAL);
748 	newcred = crget();
749 	PROC_LOCK(td->td_proc);
750 	oldcred = td->td_proc->p_ucred;
751 	crcopy(newcred, oldcred);
752 #ifdef MAC
753 	error = mac_cred_check_setaudit_addr(oldcred, &aia);
754 	if (error)
755 		goto fail;
756 #endif
757 	error = priv_check_cred(oldcred, PRIV_AUDIT_SETAUDIT, 0);
758 	if (error)
759 		goto fail;
760 	newcred->cr_audit = aia;
761 	proc_set_cred(td->td_proc, newcred);
762 	PROC_UNLOCK(td->td_proc);
763 	crfree(oldcred);
764 	return (0);
765 fail:
766 	PROC_UNLOCK(td->td_proc);
767 	crfree(newcred);
768 	return (error);
769 }
770 
771 /*
772  * Syscall to manage audit files.
773  */
774 /* ARGSUSED */
775 int
776 sys_auditctl(struct thread *td, struct auditctl_args *uap)
777 {
778 	struct nameidata nd;
779 	struct ucred *cred;
780 	struct vnode *vp;
781 	int error = 0;
782 	int flags;
783 
784 	if (jailed(td->td_ucred))
785 		return (ENOSYS);
786 	error = priv_check(td, PRIV_AUDIT_CONTROL);
787 	if (error)
788 		return (error);
789 
790 	vp = NULL;
791 	cred = NULL;
792 
793 	/*
794 	 * If a path is specified, open the replacement vnode, perform
795 	 * validity checks, and grab another reference to the current
796 	 * credential.
797 	 *
798 	 * On Darwin, a NULL path argument is also used to disable audit.
799 	 */
800 	if (uap->path == NULL)
801 		return (EINVAL);
802 
803 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1,
804 	    UIO_USERSPACE, uap->path, td);
805 	flags = AUDIT_OPEN_FLAGS;
806 	error = vn_open(&nd, &flags, 0, NULL);
807 	if (error)
808 		return (error);
809 	vp = nd.ni_vp;
810 #ifdef MAC
811 	error = mac_system_check_auditctl(td->td_ucred, vp);
812 	VOP_UNLOCK(vp, 0);
813 	if (error) {
814 		vn_close(vp, AUDIT_CLOSE_FLAGS, td->td_ucred, td);
815 		return (error);
816 	}
817 #else
818 	VOP_UNLOCK(vp, 0);
819 #endif
820 	NDFREE(&nd, NDF_ONLY_PNBUF);
821 	if (vp->v_type != VREG) {
822 		vn_close(vp, AUDIT_CLOSE_FLAGS, td->td_ucred, td);
823 		return (EINVAL);
824 	}
825 	cred = td->td_ucred;
826 	crhold(cred);
827 
828 	/*
829 	 * XXXAUDIT: Should audit_suspended actually be cleared by
830 	 * audit_worker?
831 	 */
832 	audit_suspended = 0;
833 
834 	audit_rotate_vnode(cred, vp);
835 
836 	return (error);
837 }
838 
839 #else /* !AUDIT */
840 
841 int
842 sys_audit(struct thread *td, struct audit_args *uap)
843 {
844 
845 	return (ENOSYS);
846 }
847 
848 int
849 sys_auditon(struct thread *td, struct auditon_args *uap)
850 {
851 
852 	return (ENOSYS);
853 }
854 
855 int
856 sys_getauid(struct thread *td, struct getauid_args *uap)
857 {
858 
859 	return (ENOSYS);
860 }
861 
862 int
863 sys_setauid(struct thread *td, struct setauid_args *uap)
864 {
865 
866 	return (ENOSYS);
867 }
868 
869 int
870 sys_getaudit(struct thread *td, struct getaudit_args *uap)
871 {
872 
873 	return (ENOSYS);
874 }
875 
876 int
877 sys_setaudit(struct thread *td, struct setaudit_args *uap)
878 {
879 
880 	return (ENOSYS);
881 }
882 
883 int
884 sys_getaudit_addr(struct thread *td, struct getaudit_addr_args *uap)
885 {
886 
887 	return (ENOSYS);
888 }
889 
890 int
891 sys_setaudit_addr(struct thread *td, struct setaudit_addr_args *uap)
892 {
893 
894 	return (ENOSYS);
895 }
896 
897 int
898 sys_auditctl(struct thread *td, struct auditctl_args *uap)
899 {
900 
901 	return (ENOSYS);
902 }
903 #endif /* AUDIT */
904