xref: /freebsd/sys/security/mac_lomac/mac_lomac.c (revision b28624fde638caadd4a89f50c9b7e7da0f98c4d2)
1 /*-
2  * Copyright (c) 1999-2002, 2007 Robert N. M. Watson
3  * Copyright (c) 2001-2005 Networks Associates Technology, Inc.
4  * All rights reserved.
5  *
6  * This software was developed by Robert Watson for the TrustedBSD Project.
7  *
8  * This software was developed for the FreeBSD Project in part by NAI Labs,
9  * the Security Research Division of Network Associates, Inc. under
10  * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
11  * CHATS 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  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $FreeBSD$
35  */
36 
37 /*
38  * Developed by the TrustedBSD Project.
39  *
40  * Low-watermark floating label mandatory integrity policy.
41  */
42 
43 #include <sys/types.h>
44 #include <sys/param.h>
45 #include <sys/acl.h>
46 #include <sys/conf.h>
47 #include <sys/extattr.h>
48 #include <sys/kernel.h>
49 #include <sys/malloc.h>
50 #include <sys/mman.h>
51 #include <sys/mount.h>
52 #include <sys/priv.h>
53 #include <sys/proc.h>
54 #include <sys/sbuf.h>
55 #include <sys/systm.h>
56 #include <sys/sysproto.h>
57 #include <sys/sysent.h>
58 #include <sys/systm.h>
59 #include <sys/vnode.h>
60 #include <sys/file.h>
61 #include <sys/socket.h>
62 #include <sys/socketvar.h>
63 #include <sys/sx.h>
64 #include <sys/pipe.h>
65 #include <sys/sysctl.h>
66 #include <sys/syslog.h>
67 
68 #include <fs/devfs/devfs.h>
69 
70 #include <net/bpfdesc.h>
71 #include <net/if.h>
72 #include <net/if_types.h>
73 #include <net/if_var.h>
74 
75 #include <netinet/in.h>
76 #include <netinet/in_pcb.h>
77 #include <netinet/ip_var.h>
78 
79 #include <vm/vm.h>
80 
81 #include <security/mac/mac_policy.h>
82 #include <security/mac/mac_framework.h>
83 #include <security/mac_lomac/mac_lomac.h>
84 
85 struct mac_lomac_proc {
86 	struct mac_lomac mac_lomac;
87 	struct mtx mtx;
88 };
89 
90 SYSCTL_DECL(_security_mac);
91 
92 SYSCTL_NODE(_security_mac, OID_AUTO, lomac, CTLFLAG_RW, 0,
93     "TrustedBSD mac_lomac policy controls");
94 
95 static int	mac_lomac_label_size = sizeof(struct mac_lomac);
96 SYSCTL_INT(_security_mac_lomac, OID_AUTO, label_size, CTLFLAG_RD,
97     &mac_lomac_label_size, 0, "Size of struct mac_lomac");
98 
99 static int	mac_lomac_enabled = 1;
100 SYSCTL_INT(_security_mac_lomac, OID_AUTO, enabled, CTLFLAG_RW,
101     &mac_lomac_enabled, 0, "Enforce MAC/LOMAC policy");
102 TUNABLE_INT("security.mac.lomac.enabled", &mac_lomac_enabled);
103 
104 static int	destroyed_not_inited;
105 SYSCTL_INT(_security_mac_lomac, OID_AUTO, destroyed_not_inited, CTLFLAG_RD,
106     &destroyed_not_inited, 0, "Count of labels destroyed but not inited");
107 
108 static int	trust_all_interfaces = 0;
109 SYSCTL_INT(_security_mac_lomac, OID_AUTO, trust_all_interfaces, CTLFLAG_RD,
110     &trust_all_interfaces, 0, "Consider all interfaces 'trusted' by MAC/LOMAC");
111 TUNABLE_INT("security.mac.lomac.trust_all_interfaces", &trust_all_interfaces);
112 
113 static char	trusted_interfaces[128];
114 SYSCTL_STRING(_security_mac_lomac, OID_AUTO, trusted_interfaces, CTLFLAG_RD,
115     trusted_interfaces, 0, "Interfaces considered 'trusted' by MAC/LOMAC");
116 TUNABLE_STR("security.mac.lomac.trusted_interfaces", trusted_interfaces,
117     sizeof(trusted_interfaces));
118 
119 static int	ptys_equal = 0;
120 SYSCTL_INT(_security_mac_lomac, OID_AUTO, ptys_equal, CTLFLAG_RW,
121     &ptys_equal, 0, "Label pty devices as lomac/equal on create");
122 TUNABLE_INT("security.mac.lomac.ptys_equal", &ptys_equal);
123 
124 static int	revocation_enabled = 1;
125 SYSCTL_INT(_security_mac_lomac, OID_AUTO, revocation_enabled, CTLFLAG_RW,
126     &revocation_enabled, 0, "Revoke access to objects on relabel");
127 TUNABLE_INT("security.mac.lomac.revocation_enabled", &revocation_enabled);
128 
129 static int	mac_lomac_slot;
130 #define	SLOT(l)	((struct mac_lomac *)mac_label_get((l), mac_lomac_slot))
131 #define	SLOT_SET(l, val) mac_label_set((l), mac_lomac_slot, (uintptr_t)(val))
132 #define	PSLOT(l) ((struct mac_lomac_proc *)				\
133     mac_label_get((l), mac_lomac_slot))
134 #define	PSLOT_SET(l, val) mac_label_set((l), mac_lomac_slot, (uintptr_t)(val))
135 
136 MALLOC_DEFINE(M_MACLOMAC, "mac_lomac_label", "MAC/LOMAC labels");
137 
138 static struct mac_lomac *
139 lomac_alloc(int flag)
140 {
141 	struct mac_lomac *mac_lomac;
142 
143 	mac_lomac = malloc(sizeof(struct mac_lomac), M_MACLOMAC, M_ZERO | flag);
144 
145 	return (mac_lomac);
146 }
147 
148 static void
149 lomac_free(struct mac_lomac *mac_lomac)
150 {
151 
152 	if (mac_lomac != NULL)
153 		free(mac_lomac, M_MACLOMAC);
154 	else
155 		atomic_add_int(&destroyed_not_inited, 1);
156 }
157 
158 static int
159 lomac_atmostflags(struct mac_lomac *mac_lomac, int flags)
160 {
161 
162 	if ((mac_lomac->ml_flags & flags) != mac_lomac->ml_flags)
163 		return (EINVAL);
164 	return (0);
165 }
166 
167 static int
168 mac_lomac_dominate_element(struct mac_lomac_element *a,
169     struct mac_lomac_element *b)
170 {
171 
172 	switch (a->mle_type) {
173 	case MAC_LOMAC_TYPE_EQUAL:
174 	case MAC_LOMAC_TYPE_HIGH:
175 		return (1);
176 
177 	case MAC_LOMAC_TYPE_LOW:
178 		switch (b->mle_type) {
179 		case MAC_LOMAC_TYPE_GRADE:
180 		case MAC_LOMAC_TYPE_HIGH:
181 			return (0);
182 
183 		case MAC_LOMAC_TYPE_EQUAL:
184 		case MAC_LOMAC_TYPE_LOW:
185 			return (1);
186 
187 		default:
188 			panic("mac_lomac_dominate_element: b->mle_type invalid");
189 		}
190 
191 	case MAC_LOMAC_TYPE_GRADE:
192 		switch (b->mle_type) {
193 		case MAC_LOMAC_TYPE_EQUAL:
194 		case MAC_LOMAC_TYPE_LOW:
195 			return (1);
196 
197 		case MAC_LOMAC_TYPE_HIGH:
198 			return (0);
199 
200 		case MAC_LOMAC_TYPE_GRADE:
201 			return (a->mle_grade >= b->mle_grade);
202 
203 		default:
204 			panic("mac_lomac_dominate_element: b->mle_type invalid");
205 		}
206 
207 	default:
208 		panic("mac_lomac_dominate_element: a->mle_type invalid");
209 	}
210 }
211 
212 static int
213 mac_lomac_range_in_range(struct mac_lomac *rangea, struct mac_lomac *rangeb)
214 {
215 
216 	return (mac_lomac_dominate_element(&rangeb->ml_rangehigh,
217 	    &rangea->ml_rangehigh) &&
218 	    mac_lomac_dominate_element(&rangea->ml_rangelow,
219 	    &rangeb->ml_rangelow));
220 }
221 
222 static int
223 mac_lomac_single_in_range(struct mac_lomac *single, struct mac_lomac *range)
224 {
225 
226 	KASSERT((single->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
227 	    ("mac_lomac_single_in_range: a not single"));
228 	KASSERT((range->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
229 	    ("mac_lomac_single_in_range: b not range"));
230 
231 	return (mac_lomac_dominate_element(&range->ml_rangehigh,
232 	    &single->ml_single) &&
233 	    mac_lomac_dominate_element(&single->ml_single,
234 	    &range->ml_rangelow));
235 }
236 
237 static int
238 mac_lomac_auxsingle_in_range(struct mac_lomac *single, struct mac_lomac *range)
239 {
240 
241 	KASSERT((single->ml_flags & MAC_LOMAC_FLAG_AUX) != 0,
242 	    ("mac_lomac_single_in_range: a not auxsingle"));
243 	KASSERT((range->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
244 	    ("mac_lomac_single_in_range: b not range"));
245 
246 	return (mac_lomac_dominate_element(&range->ml_rangehigh,
247 	    &single->ml_auxsingle) &&
248 	    mac_lomac_dominate_element(&single->ml_auxsingle,
249 	    &range->ml_rangelow));
250 }
251 
252 static int
253 mac_lomac_dominate_single(struct mac_lomac *a, struct mac_lomac *b)
254 {
255 	KASSERT((a->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
256 	    ("mac_lomac_dominate_single: a not single"));
257 	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
258 	    ("mac_lomac_dominate_single: b not single"));
259 
260 	return (mac_lomac_dominate_element(&a->ml_single, &b->ml_single));
261 }
262 
263 static int
264 mac_lomac_subject_dominate(struct mac_lomac *a, struct mac_lomac *b)
265 {
266 	KASSERT((~a->ml_flags &
267 	    (MAC_LOMAC_FLAG_SINGLE | MAC_LOMAC_FLAG_RANGE)) == 0,
268 	    ("mac_lomac_dominate_single: a not subject"));
269 	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
270 	    ("mac_lomac_dominate_single: b not single"));
271 
272 	return (mac_lomac_dominate_element(&a->ml_rangehigh,
273 	    &b->ml_single));
274 }
275 
276 static int
277 mac_lomac_equal_element(struct mac_lomac_element *a, struct mac_lomac_element *b)
278 {
279 
280 	if (a->mle_type == MAC_LOMAC_TYPE_EQUAL ||
281 	    b->mle_type == MAC_LOMAC_TYPE_EQUAL)
282 		return (1);
283 
284 	return (a->mle_type == b->mle_type && a->mle_grade == b->mle_grade);
285 }
286 
287 static int
288 mac_lomac_equal_single(struct mac_lomac *a, struct mac_lomac *b)
289 {
290 
291 	KASSERT((a->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
292 	    ("mac_lomac_equal_single: a not single"));
293 	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
294 	    ("mac_lomac_equal_single: b not single"));
295 
296 	return (mac_lomac_equal_element(&a->ml_single, &b->ml_single));
297 }
298 
299 static int
300 mac_lomac_contains_equal(struct mac_lomac *mac_lomac)
301 {
302 
303 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_SINGLE)
304 		if (mac_lomac->ml_single.mle_type == MAC_LOMAC_TYPE_EQUAL)
305 			return (1);
306 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_AUX)
307 		if (mac_lomac->ml_auxsingle.mle_type == MAC_LOMAC_TYPE_EQUAL)
308 			return (1);
309 
310 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_RANGE) {
311 		if (mac_lomac->ml_rangelow.mle_type == MAC_LOMAC_TYPE_EQUAL)
312 			return (1);
313 		if (mac_lomac->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_EQUAL)
314 			return (1);
315 	}
316 
317 	return (0);
318 }
319 
320 static int
321 mac_lomac_subject_privileged(struct mac_lomac *mac_lomac)
322 {
323 
324 	KASSERT((mac_lomac->ml_flags & MAC_LOMAC_FLAGS_BOTH) ==
325 	    MAC_LOMAC_FLAGS_BOTH,
326 	    ("mac_lomac_subject_privileged: subject doesn't have both labels"));
327 
328 	/* If the single is EQUAL, it's ok. */
329 	if (mac_lomac->ml_single.mle_type == MAC_LOMAC_TYPE_EQUAL)
330 		return (0);
331 
332 	/* If either range endpoint is EQUAL, it's ok. */
333 	if (mac_lomac->ml_rangelow.mle_type == MAC_LOMAC_TYPE_EQUAL ||
334 	    mac_lomac->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_EQUAL)
335 		return (0);
336 
337 	/* If the range is low-high, it's ok. */
338 	if (mac_lomac->ml_rangelow.mle_type == MAC_LOMAC_TYPE_LOW &&
339 	    mac_lomac->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_HIGH)
340 		return (0);
341 
342 	/* It's not ok. */
343 	return (EPERM);
344 }
345 
346 static int
347 mac_lomac_high_single(struct mac_lomac *mac_lomac)
348 {
349 
350 	KASSERT((mac_lomac->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
351 	    ("mac_lomac_high_single: mac_lomac not single"));
352 
353 	return (mac_lomac->ml_single.mle_type == MAC_LOMAC_TYPE_HIGH);
354 }
355 
356 static int
357 mac_lomac_valid(struct mac_lomac *mac_lomac)
358 {
359 
360 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
361 		switch (mac_lomac->ml_single.mle_type) {
362 		case MAC_LOMAC_TYPE_GRADE:
363 		case MAC_LOMAC_TYPE_EQUAL:
364 		case MAC_LOMAC_TYPE_HIGH:
365 		case MAC_LOMAC_TYPE_LOW:
366 			break;
367 
368 		default:
369 			return (EINVAL);
370 		}
371 	} else {
372 		if (mac_lomac->ml_single.mle_type != MAC_LOMAC_TYPE_UNDEF)
373 			return (EINVAL);
374 	}
375 
376 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_AUX) {
377 		switch (mac_lomac->ml_auxsingle.mle_type) {
378 		case MAC_LOMAC_TYPE_GRADE:
379 		case MAC_LOMAC_TYPE_EQUAL:
380 		case MAC_LOMAC_TYPE_HIGH:
381 		case MAC_LOMAC_TYPE_LOW:
382 			break;
383 
384 		default:
385 			return (EINVAL);
386 		}
387 	} else {
388 		if (mac_lomac->ml_auxsingle.mle_type != MAC_LOMAC_TYPE_UNDEF)
389 			return (EINVAL);
390 	}
391 
392 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_RANGE) {
393 		switch (mac_lomac->ml_rangelow.mle_type) {
394 		case MAC_LOMAC_TYPE_GRADE:
395 		case MAC_LOMAC_TYPE_EQUAL:
396 		case MAC_LOMAC_TYPE_HIGH:
397 		case MAC_LOMAC_TYPE_LOW:
398 			break;
399 
400 		default:
401 			return (EINVAL);
402 		}
403 
404 		switch (mac_lomac->ml_rangehigh.mle_type) {
405 		case MAC_LOMAC_TYPE_GRADE:
406 		case MAC_LOMAC_TYPE_EQUAL:
407 		case MAC_LOMAC_TYPE_HIGH:
408 		case MAC_LOMAC_TYPE_LOW:
409 			break;
410 
411 		default:
412 			return (EINVAL);
413 		}
414 		if (!mac_lomac_dominate_element(&mac_lomac->ml_rangehigh,
415 		    &mac_lomac->ml_rangelow))
416 			return (EINVAL);
417 	} else {
418 		if (mac_lomac->ml_rangelow.mle_type != MAC_LOMAC_TYPE_UNDEF ||
419 		    mac_lomac->ml_rangehigh.mle_type != MAC_LOMAC_TYPE_UNDEF)
420 			return (EINVAL);
421 	}
422 
423 	return (0);
424 }
425 
426 static void
427 mac_lomac_set_range(struct mac_lomac *mac_lomac, u_short typelow,
428     u_short gradelow, u_short typehigh, u_short gradehigh)
429 {
430 
431 	mac_lomac->ml_rangelow.mle_type = typelow;
432 	mac_lomac->ml_rangelow.mle_grade = gradelow;
433 	mac_lomac->ml_rangehigh.mle_type = typehigh;
434 	mac_lomac->ml_rangehigh.mle_grade = gradehigh;
435 	mac_lomac->ml_flags |= MAC_LOMAC_FLAG_RANGE;
436 }
437 
438 static void
439 mac_lomac_set_single(struct mac_lomac *mac_lomac, u_short type, u_short grade)
440 {
441 
442 	mac_lomac->ml_single.mle_type = type;
443 	mac_lomac->ml_single.mle_grade = grade;
444 	mac_lomac->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
445 }
446 
447 static void
448 mac_lomac_copy_range(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
449 {
450 
451 	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
452 	    ("mac_lomac_copy_range: labelfrom not range"));
453 
454 	labelto->ml_rangelow = labelfrom->ml_rangelow;
455 	labelto->ml_rangehigh = labelfrom->ml_rangehigh;
456 	labelto->ml_flags |= MAC_LOMAC_FLAG_RANGE;
457 }
458 
459 static void
460 mac_lomac_copy_single(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
461 {
462 
463 	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
464 	    ("mac_lomac_copy_single: labelfrom not single"));
465 
466 	labelto->ml_single = labelfrom->ml_single;
467 	labelto->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
468 }
469 
470 static void
471 mac_lomac_copy_auxsingle(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
472 {
473 
474 	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_AUX) != 0,
475 	    ("mac_lomac_copy_auxsingle: labelfrom not auxsingle"));
476 
477 	labelto->ml_auxsingle = labelfrom->ml_auxsingle;
478 	labelto->ml_flags |= MAC_LOMAC_FLAG_AUX;
479 }
480 
481 static void
482 mac_lomac_copy(struct mac_lomac *source, struct mac_lomac *dest)
483 {
484 
485 	if (source->ml_flags & MAC_LOMAC_FLAG_SINGLE)
486 		mac_lomac_copy_single(source, dest);
487 	if (source->ml_flags & MAC_LOMAC_FLAG_AUX)
488 		mac_lomac_copy_auxsingle(source, dest);
489 	if (source->ml_flags & MAC_LOMAC_FLAG_RANGE)
490 		mac_lomac_copy_range(source, dest);
491 }
492 
493 static int	mac_lomac_to_string(struct sbuf *sb,
494 		    struct mac_lomac *mac_lomac);
495 
496 static int
497 maybe_demote(struct mac_lomac *subjlabel, struct mac_lomac *objlabel,
498     const char *actionname, const char *objname, struct vnode *vp)
499 {
500 	struct sbuf subjlabel_sb, subjtext_sb, objlabel_sb;
501 	char *subjlabeltext, *objlabeltext, *subjtext;
502 	struct mac_lomac cached_subjlabel;
503 	struct mac_lomac_proc *subj;
504 	struct vattr va;
505 	struct proc *p;
506 	pid_t pgid;
507 
508 	subj = PSLOT(curthread->td_proc->p_label);
509 
510 	p = curthread->td_proc;
511 	mtx_lock(&subj->mtx);
512         if (subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) {
513 		/*
514 		 * Check to see if the pending demotion would be more or
515 		 * less severe than this one, and keep the more severe.
516 		 * This can only happen for a multi-threaded application.
517 		 */
518 		if (mac_lomac_dominate_single(objlabel, &subj->mac_lomac)) {
519 			mtx_unlock(&subj->mtx);
520 			return (0);
521 		}
522 	}
523 	bzero(&subj->mac_lomac, sizeof(subj->mac_lomac));
524 	/*
525 	 * Always demote the single label.
526 	 */
527 	mac_lomac_copy_single(objlabel, &subj->mac_lomac);
528 	/*
529 	 * Start with the original range, then minimize each side of
530 	 * the range to the point of not dominating the object.  The
531 	 * high side will always be demoted, of course.
532 	 */
533 	mac_lomac_copy_range(subjlabel, &subj->mac_lomac);
534 	if (!mac_lomac_dominate_element(&objlabel->ml_single,
535 	    &subj->mac_lomac.ml_rangelow))
536 		subj->mac_lomac.ml_rangelow = objlabel->ml_single;
537 	subj->mac_lomac.ml_rangehigh = objlabel->ml_single;
538 	subj->mac_lomac.ml_flags |= MAC_LOMAC_FLAG_UPDATE;
539 	thread_lock(curthread);
540 	curthread->td_flags |= TDF_ASTPENDING;
541 	curthread->td_proc->p_sflag |= PS_MACPEND;
542 	thread_unlock(curthread);
543 
544 	/*
545 	 * Avoid memory allocation while holding a mutex; cache the
546 	 * label.
547 	 */
548 	mac_lomac_copy_single(&subj->mac_lomac, &cached_subjlabel);
549 	mtx_unlock(&subj->mtx);
550 
551 	sbuf_new(&subjlabel_sb, NULL, 0, SBUF_AUTOEXTEND);
552 	mac_lomac_to_string(&subjlabel_sb, subjlabel);
553 	sbuf_finish(&subjlabel_sb);
554 	subjlabeltext = sbuf_data(&subjlabel_sb);
555 
556 	sbuf_new(&subjtext_sb, NULL, 0, SBUF_AUTOEXTEND);
557 	mac_lomac_to_string(&subjtext_sb, &subj->mac_lomac);
558 	sbuf_finish(&subjtext_sb);
559 	subjtext = sbuf_data(&subjtext_sb);
560 
561 	sbuf_new(&objlabel_sb, NULL, 0, SBUF_AUTOEXTEND);
562 	mac_lomac_to_string(&objlabel_sb, objlabel);
563 	sbuf_finish(&objlabel_sb);
564 	objlabeltext = sbuf_data(&objlabel_sb);
565 
566 	pgid = p->p_pgrp->pg_id;		/* XXX could be stale? */
567 	if (vp != NULL && VOP_GETATTR(vp, &va, curthread->td_ucred,
568 	    curthread) == 0) {
569 		log(LOG_INFO, "LOMAC: level-%s subject p%dg%du%d:%s demoted to"
570 		    " level %s after %s a level-%s %s (inode=%ld, "
571 		    "mountpount=%s)\n",
572 		    subjlabeltext, p->p_pid, pgid, curthread->td_ucred->cr_uid,
573 		    p->p_comm, subjtext, actionname, objlabeltext, objname,
574 		    va.va_fileid, vp->v_mount->mnt_stat.f_mntonname);
575 	} else {
576 		log(LOG_INFO, "LOMAC: level-%s subject p%dg%du%d:%s demoted to"
577 		    " level %s after %s a level-%s %s\n",
578 		    subjlabeltext, p->p_pid, pgid, curthread->td_ucred->cr_uid,
579 		    p->p_comm, subjtext, actionname, objlabeltext, objname);
580 	}
581 
582 	sbuf_delete(&subjlabel_sb);
583 	sbuf_delete(&subjtext_sb);
584 	sbuf_delete(&objlabel_sb);
585 
586 	return (0);
587 }
588 
589 /*
590  * Relabel "to" to "from" only if "from" is a valid label (contains
591  * at least a single), as for a relabel operation which may or may
592  * not involve a relevant label.
593  */
594 static void
595 try_relabel(struct mac_lomac *from, struct mac_lomac *to)
596 {
597 
598 	if (from->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
599 		bzero(to, sizeof(*to));
600 		mac_lomac_copy(from, to);
601 	}
602 }
603 
604 /*
605  * Policy module operations.
606  */
607 static void
608 mac_lomac_init(struct mac_policy_conf *conf)
609 {
610 
611 }
612 
613 /*
614  * Label operations.
615  */
616 static void
617 mac_lomac_init_label(struct label *label)
618 {
619 
620 	SLOT_SET(label, lomac_alloc(M_WAITOK));
621 }
622 
623 static int
624 mac_lomac_init_label_waitcheck(struct label *label, int flag)
625 {
626 
627 	SLOT_SET(label, lomac_alloc(flag));
628 	if (SLOT(label) == NULL)
629 		return (ENOMEM);
630 
631 	return (0);
632 }
633 
634 static void
635 mac_lomac_init_proc_label(struct label *label)
636 {
637 
638 	PSLOT_SET(label, malloc(sizeof(struct mac_lomac_proc), M_MACLOMAC,
639 	    M_ZERO | M_WAITOK));
640 	mtx_init(&PSLOT(label)->mtx, "MAC/Lomac proc lock", NULL, MTX_DEF);
641 }
642 
643 static void
644 mac_lomac_destroy_label(struct label *label)
645 {
646 
647 	lomac_free(SLOT(label));
648 	SLOT_SET(label, NULL);
649 }
650 
651 static void
652 mac_lomac_destroy_proc_label(struct label *label)
653 {
654 
655 	mtx_destroy(&PSLOT(label)->mtx);
656 	FREE(PSLOT(label), M_MACLOMAC);
657 	PSLOT_SET(label, NULL);
658 }
659 
660 static int
661 mac_lomac_element_to_string(struct sbuf *sb, struct mac_lomac_element *element)
662 {
663 
664 	switch (element->mle_type) {
665 	case MAC_LOMAC_TYPE_HIGH:
666 		return (sbuf_printf(sb, "high"));
667 
668 	case MAC_LOMAC_TYPE_LOW:
669 		return (sbuf_printf(sb, "low"));
670 
671 	case MAC_LOMAC_TYPE_EQUAL:
672 		return (sbuf_printf(sb, "equal"));
673 
674 	case MAC_LOMAC_TYPE_GRADE:
675 		return (sbuf_printf(sb, "%d", element->mle_grade));
676 
677 	default:
678 		panic("mac_lomac_element_to_string: invalid type (%d)",
679 		    element->mle_type);
680 	}
681 }
682 
683 static int
684 mac_lomac_to_string(struct sbuf *sb, struct mac_lomac *mac_lomac)
685 {
686 
687 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
688 		if (mac_lomac_element_to_string(sb, &mac_lomac->ml_single)
689 		    == -1)
690 			return (EINVAL);
691 	}
692 
693 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_AUX) {
694 		if (sbuf_putc(sb, '[') == -1)
695 			return (EINVAL);
696 
697 		if (mac_lomac_element_to_string(sb, &mac_lomac->ml_auxsingle)
698 		    == -1)
699 			return (EINVAL);
700 
701 		if (sbuf_putc(sb, ']') == -1)
702 			return (EINVAL);
703 	}
704 
705 	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_RANGE) {
706 		if (sbuf_putc(sb, '(') == -1)
707 			return (EINVAL);
708 
709 		if (mac_lomac_element_to_string(sb, &mac_lomac->ml_rangelow)
710 		    == -1)
711 			return (EINVAL);
712 
713 		if (sbuf_putc(sb, '-') == -1)
714 			return (EINVAL);
715 
716 		if (mac_lomac_element_to_string(sb, &mac_lomac->ml_rangehigh)
717 		    == -1)
718 			return (EINVAL);
719 
720 		if (sbuf_putc(sb, ')') == -1)
721 			return (EINVAL);
722 	}
723 
724 	return (0);
725 }
726 
727 static int
728 mac_lomac_externalize_label(struct label *label, char *element_name,
729     struct sbuf *sb, int *claimed)
730 {
731 	struct mac_lomac *mac_lomac;
732 
733 	if (strcmp(MAC_LOMAC_LABEL_NAME, element_name) != 0)
734 		return (0);
735 
736 	(*claimed)++;
737 
738 	mac_lomac = SLOT(label);
739 
740 	return (mac_lomac_to_string(sb, mac_lomac));
741 }
742 
743 static int
744 mac_lomac_parse_element(struct mac_lomac_element *element, char *string)
745 {
746 
747 	if (strcmp(string, "high") == 0 ||
748 	    strcmp(string, "hi") == 0) {
749 		element->mle_type = MAC_LOMAC_TYPE_HIGH;
750 		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
751 	} else if (strcmp(string, "low") == 0 ||
752 	    strcmp(string, "lo") == 0) {
753 		element->mle_type = MAC_LOMAC_TYPE_LOW;
754 		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
755 	} else if (strcmp(string, "equal") == 0 ||
756 	    strcmp(string, "eq") == 0) {
757 		element->mle_type = MAC_LOMAC_TYPE_EQUAL;
758 		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
759 	} else {
760 		char *p0, *p1;
761 		int d;
762 
763 		p0 = string;
764 		d = strtol(p0, &p1, 10);
765 
766 		if (d < 0 || d > 65535)
767 			return (EINVAL);
768 		element->mle_type = MAC_LOMAC_TYPE_GRADE;
769 		element->mle_grade = d;
770 
771 		if (p1 == p0 || *p1 != '\0')
772 			return (EINVAL);
773 	}
774 
775 	return (0);
776 }
777 
778 /*
779  * Note: destructively consumes the string, make a local copy before
780  * calling if that's a problem.
781  */
782 static int
783 mac_lomac_parse(struct mac_lomac *mac_lomac, char *string)
784 {
785 	char *range, *rangeend, *rangehigh, *rangelow, *single, *auxsingle,
786 	    *auxsingleend;
787 	int error;
788 
789 	/* Do we have a range? */
790 	single = string;
791 	range = index(string, '(');
792 	if (range == single)
793 		single = NULL;
794 	auxsingle = index(string, '[');
795 	if (auxsingle == single)
796 		single = NULL;
797 	if (range != NULL && auxsingle != NULL)
798 		return (EINVAL);
799 	rangelow = rangehigh = NULL;
800 	if (range != NULL) {
801 		/* Nul terminate the end of the single string. */
802 		*range = '\0';
803 		range++;
804 		rangelow = range;
805 		rangehigh = index(rangelow, '-');
806 		if (rangehigh == NULL)
807 			return (EINVAL);
808 		rangehigh++;
809 		if (*rangelow == '\0' || *rangehigh == '\0')
810 			return (EINVAL);
811 		rangeend = index(rangehigh, ')');
812 		if (rangeend == NULL)
813 			return (EINVAL);
814 		if (*(rangeend + 1) != '\0')
815 			return (EINVAL);
816 		/* Nul terminate the ends of the ranges. */
817 		*(rangehigh - 1) = '\0';
818 		*rangeend = '\0';
819 	}
820 	KASSERT((rangelow != NULL && rangehigh != NULL) ||
821 	    (rangelow == NULL && rangehigh == NULL),
822 	    ("mac_lomac_internalize_label: range mismatch"));
823 	if (auxsingle != NULL) {
824 		/* Nul terminate the end of the single string. */
825 		*auxsingle = '\0';
826 		auxsingle++;
827 		auxsingleend = index(auxsingle, ']');
828 		if (auxsingleend == NULL)
829 			return (EINVAL);
830 		if (*(auxsingleend + 1) != '\0')
831 			return (EINVAL);
832 		/* Nul terminate the end of the auxsingle. */
833 		*auxsingleend = '\0';
834 	}
835 
836 	bzero(mac_lomac, sizeof(*mac_lomac));
837 	if (single != NULL) {
838 		error = mac_lomac_parse_element(&mac_lomac->ml_single, single);
839 		if (error)
840 			return (error);
841 		mac_lomac->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
842 	}
843 
844 	if (auxsingle != NULL) {
845 		error = mac_lomac_parse_element(&mac_lomac->ml_auxsingle,
846 		    auxsingle);
847 		if (error)
848 			return (error);
849 		mac_lomac->ml_flags |= MAC_LOMAC_FLAG_AUX;
850 	}
851 
852 	if (rangelow != NULL) {
853 		error = mac_lomac_parse_element(&mac_lomac->ml_rangelow,
854 		    rangelow);
855 		if (error)
856 			return (error);
857 		error = mac_lomac_parse_element(&mac_lomac->ml_rangehigh,
858 		    rangehigh);
859 		if (error)
860 			return (error);
861 		mac_lomac->ml_flags |= MAC_LOMAC_FLAG_RANGE;
862 	}
863 
864 	error = mac_lomac_valid(mac_lomac);
865 	if (error)
866 		return (error);
867 
868 	return (0);
869 }
870 
871 static int
872 mac_lomac_internalize_label(struct label *label, char *element_name,
873     char *element_data, int *claimed)
874 {
875 	struct mac_lomac *mac_lomac, mac_lomac_temp;
876 	int error;
877 
878 	if (strcmp(MAC_LOMAC_LABEL_NAME, element_name) != 0)
879 		return (0);
880 
881 	(*claimed)++;
882 
883 	error = mac_lomac_parse(&mac_lomac_temp, element_data);
884 	if (error)
885 		return (error);
886 
887 	mac_lomac = SLOT(label);
888 	*mac_lomac = mac_lomac_temp;
889 
890 	return (0);
891 }
892 
893 static void
894 mac_lomac_copy_label(struct label *src, struct label *dest)
895 {
896 
897 	*SLOT(dest) = *SLOT(src);
898 }
899 
900 /*
901  * Labeling event operations: file system objects, and things that look
902  * a lot like file system objects.
903  */
904 static void
905 mac_lomac_create_devfs_device(struct ucred *cred, struct mount *mp,
906     struct cdev *dev, struct devfs_dirent *de, struct label *delabel)
907 {
908 	struct mac_lomac *mac_lomac;
909 	int lomac_type;
910 
911 	mac_lomac = SLOT(delabel);
912 	if (strcmp(dev->si_name, "null") == 0 ||
913 	    strcmp(dev->si_name, "zero") == 0 ||
914 	    strcmp(dev->si_name, "random") == 0 ||
915 	    strncmp(dev->si_name, "fd/", strlen("fd/")) == 0 ||
916 	    strncmp(dev->si_name, "ttyv", strlen("ttyv")) == 0)
917 		lomac_type = MAC_LOMAC_TYPE_EQUAL;
918 	else if (ptys_equal &&
919 	    (strncmp(dev->si_name, "ttyp", strlen("ttyp")) == 0 ||
920 	    strncmp(dev->si_name, "ptyp", strlen("ptyp")) == 0))
921 		lomac_type = MAC_LOMAC_TYPE_EQUAL;
922 	else
923 		lomac_type = MAC_LOMAC_TYPE_HIGH;
924 	mac_lomac_set_single(mac_lomac, lomac_type, 0);
925 }
926 
927 static void
928 mac_lomac_create_devfs_directory(struct mount *mp, char *dirname,
929     int dirnamelen, struct devfs_dirent *de, struct label *delabel)
930 {
931 	struct mac_lomac *mac_lomac;
932 
933 	mac_lomac = SLOT(delabel);
934 	mac_lomac_set_single(mac_lomac, MAC_LOMAC_TYPE_HIGH, 0);
935 }
936 
937 static void
938 mac_lomac_create_devfs_symlink(struct ucred *cred, struct mount *mp,
939     struct devfs_dirent *dd, struct label *ddlabel, struct devfs_dirent *de,
940     struct label *delabel)
941 {
942 	struct mac_lomac *source, *dest;
943 
944 	source = SLOT(cred->cr_label);
945 	dest = SLOT(delabel);
946 
947 	mac_lomac_copy_single(source, dest);
948 }
949 
950 static void
951 mac_lomac_create_mount(struct ucred *cred, struct mount *mp,
952     struct label *mplabel)
953 {
954 	struct mac_lomac *source, *dest;
955 
956 	source = SLOT(cred->cr_label);
957 	dest = SLOT(mplabel);
958 	mac_lomac_copy_single(source, dest);
959 }
960 
961 static void
962 mac_lomac_relabel_vnode(struct ucred *cred, struct vnode *vp,
963     struct label *vplabel, struct label *newlabel)
964 {
965 	struct mac_lomac *source, *dest;
966 
967 	source = SLOT(newlabel);
968 	dest = SLOT(vplabel);
969 
970 	try_relabel(source, dest);
971 }
972 
973 static void
974 mac_lomac_update_devfs(struct mount *mp, struct devfs_dirent *de,
975     struct label *delabel, struct vnode *vp, struct label *vplabel)
976 {
977 	struct mac_lomac *source, *dest;
978 
979 	source = SLOT(vplabel);
980 	dest = SLOT(delabel);
981 
982 	mac_lomac_copy(source, dest);
983 }
984 
985 static void
986 mac_lomac_associate_vnode_devfs(struct mount *mp, struct label *mplabel,
987     struct devfs_dirent *de, struct label *delabel, struct vnode *vp,
988     struct label *vplabel)
989 {
990 	struct mac_lomac *source, *dest;
991 
992 	source = SLOT(delabel);
993 	dest = SLOT(vplabel);
994 
995 	mac_lomac_copy_single(source, dest);
996 }
997 
998 static int
999 mac_lomac_associate_vnode_extattr(struct mount *mp, struct label *mplabel,
1000     struct vnode *vp, struct label *vplabel)
1001 {
1002 	struct mac_lomac temp, *source, *dest;
1003 	int buflen, error;
1004 
1005 	source = SLOT(mplabel);
1006 	dest = SLOT(vplabel);
1007 
1008 	buflen = sizeof(temp);
1009 	bzero(&temp, buflen);
1010 
1011 	error = vn_extattr_get(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
1012 	    MAC_LOMAC_EXTATTR_NAME, &buflen, (char *)&temp, curthread);
1013 	if (error == ENOATTR || error == EOPNOTSUPP) {
1014 		/* Fall back to the mntlabel. */
1015 		mac_lomac_copy_single(source, dest);
1016 		return (0);
1017 	} else if (error)
1018 		return (error);
1019 
1020 	if (buflen != sizeof(temp)) {
1021 		if (buflen != sizeof(temp) - sizeof(temp.ml_auxsingle)) {
1022 			printf("mac_lomac_associate_vnode_extattr: bad size %d\n",
1023 			    buflen);
1024 			return (EPERM);
1025 		}
1026 		bzero(&temp.ml_auxsingle, sizeof(temp.ml_auxsingle));
1027 		buflen = sizeof(temp);
1028 		(void)vn_extattr_set(vp, IO_NODELOCKED,
1029 		    MAC_LOMAC_EXTATTR_NAMESPACE, MAC_LOMAC_EXTATTR_NAME,
1030 		    buflen, (char *)&temp, curthread);
1031 	}
1032 	if (mac_lomac_valid(&temp) != 0) {
1033 		printf("mac_lomac_associate_vnode_extattr: invalid\n");
1034 		return (EPERM);
1035 	}
1036 	if ((temp.ml_flags & MAC_LOMAC_FLAGS_BOTH) != MAC_LOMAC_FLAG_SINGLE) {
1037 		printf("mac_lomac_associate_vnode_extattr: not single\n");
1038 		return (EPERM);
1039 	}
1040 
1041 	mac_lomac_copy_single(&temp, dest);
1042 	return (0);
1043 }
1044 
1045 static void
1046 mac_lomac_associate_vnode_singlelabel(struct mount *mp,
1047     struct label *mplabel, struct vnode *vp, struct label *vplabel)
1048 {
1049 	struct mac_lomac *source, *dest;
1050 
1051 	source = SLOT(mplabel);
1052 	dest = SLOT(vplabel);
1053 
1054 	mac_lomac_copy_single(source, dest);
1055 }
1056 
1057 static int
1058 mac_lomac_create_vnode_extattr(struct ucred *cred, struct mount *mp,
1059     struct label *mplabel, struct vnode *dvp, struct label *dvplabel,
1060     struct vnode *vp, struct label *vplabel, struct componentname *cnp)
1061 {
1062 	struct mac_lomac *source, *dest, *dir, temp;
1063 	size_t buflen;
1064 	int error;
1065 
1066 	buflen = sizeof(temp);
1067 	bzero(&temp, buflen);
1068 
1069 	source = SLOT(cred->cr_label);
1070 	dest = SLOT(vplabel);
1071 	dir = SLOT(dvplabel);
1072 	if (dir->ml_flags & MAC_LOMAC_FLAG_AUX) {
1073 		mac_lomac_copy_auxsingle(dir, &temp);
1074 		mac_lomac_set_single(&temp, dir->ml_auxsingle.mle_type,
1075 		    dir->ml_auxsingle.mle_grade);
1076 	} else {
1077 		mac_lomac_copy_single(source, &temp);
1078 	}
1079 
1080 	error = vn_extattr_set(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
1081 	    MAC_LOMAC_EXTATTR_NAME, buflen, (char *)&temp, curthread);
1082 	if (error == 0)
1083 		mac_lomac_copy(&temp, dest);
1084 	return (error);
1085 }
1086 
1087 static int
1088 mac_lomac_setlabel_vnode_extattr(struct ucred *cred, struct vnode *vp,
1089     struct label *vplabel, struct label *intlabel)
1090 {
1091 	struct mac_lomac *source, temp;
1092 	size_t buflen;
1093 	int error;
1094 
1095 	buflen = sizeof(temp);
1096 	bzero(&temp, buflen);
1097 
1098 	source = SLOT(intlabel);
1099 	if ((source->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
1100 		return (0);
1101 
1102 	mac_lomac_copy_single(source, &temp);
1103 	error = vn_extattr_set(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
1104 	    MAC_LOMAC_EXTATTR_NAME, buflen, (char *)&temp, curthread);
1105 	return (error);
1106 }
1107 
1108 /*
1109  * Labeling event operations: IPC object.
1110  */
1111 static void
1112 mac_lomac_create_inpcb_from_socket(struct socket *so, struct label *solabel,
1113     struct inpcb *inp, struct label *inplabel)
1114 {
1115 	struct mac_lomac *source, *dest;
1116 
1117 	source = SLOT(solabel);
1118 	dest = SLOT(inplabel);
1119 
1120 	mac_lomac_copy_single(source, dest);
1121 }
1122 
1123 static void
1124 mac_lomac_create_mbuf_from_socket(struct socket *so, struct label *solabel,
1125     struct mbuf *m, struct label *mlabel)
1126 {
1127 	struct mac_lomac *source, *dest;
1128 
1129 	source = SLOT(solabel);
1130 	dest = SLOT(mlabel);
1131 
1132 	mac_lomac_copy_single(source, dest);
1133 }
1134 
1135 static void
1136 mac_lomac_create_socket(struct ucred *cred, struct socket *so,
1137     struct label *solabel)
1138 {
1139 	struct mac_lomac *source, *dest;
1140 
1141 	source = SLOT(cred->cr_label);
1142 	dest = SLOT(solabel);
1143 
1144 	mac_lomac_copy_single(source, dest);
1145 }
1146 
1147 static void
1148 mac_lomac_create_pipe(struct ucred *cred, struct pipepair *pp,
1149     struct label *pplabel)
1150 {
1151 	struct mac_lomac *source, *dest;
1152 
1153 	source = SLOT(cred->cr_label);
1154 	dest = SLOT(pplabel);
1155 
1156 	mac_lomac_copy_single(source, dest);
1157 }
1158 
1159 static void
1160 mac_lomac_create_socket_from_socket(struct socket *oldso,
1161     struct label *oldsolabel, struct socket *newso, struct label *newsolabel)
1162 {
1163 	struct mac_lomac *source, *dest;
1164 
1165 	source = SLOT(oldsolabel);
1166 	dest = SLOT(newsolabel);
1167 
1168 	mac_lomac_copy_single(source, dest);
1169 }
1170 
1171 static void
1172 mac_lomac_relabel_socket(struct ucred *cred, struct socket *so,
1173     struct label *solabel, struct label *newlabel)
1174 {
1175 	struct mac_lomac *source, *dest;
1176 
1177 	source = SLOT(newlabel);
1178 	dest = SLOT(solabel);
1179 
1180 	try_relabel(source, dest);
1181 }
1182 
1183 static void
1184 mac_lomac_relabel_pipe(struct ucred *cred, struct pipepair *pp,
1185     struct label *pplabel, struct label *newlabel)
1186 {
1187 	struct mac_lomac *source, *dest;
1188 
1189 	source = SLOT(newlabel);
1190 	dest = SLOT(pplabel);
1191 
1192 	try_relabel(source, dest);
1193 }
1194 
1195 static void
1196 mac_lomac_set_socket_peer_from_mbuf(struct mbuf *m, struct label *mlabel,
1197     struct socket *so, struct label *sopeerlabel)
1198 {
1199 	struct mac_lomac *source, *dest;
1200 
1201 	source = SLOT(mlabel);
1202 	dest = SLOT(sopeerlabel);
1203 
1204 	mac_lomac_copy_single(source, dest);
1205 }
1206 
1207 /*
1208  * Labeling event operations: network objects.
1209  */
1210 static void
1211 mac_lomac_set_socket_peer_from_socket(struct socket *oldso,
1212     struct label *oldsolabel, struct socket *newso,
1213     struct label *newsopeerlabel)
1214 {
1215 	struct mac_lomac *source, *dest;
1216 
1217 	source = SLOT(oldsolabel);
1218 	dest = SLOT(newsopeerlabel);
1219 
1220 	mac_lomac_copy_single(source, dest);
1221 }
1222 
1223 static void
1224 mac_lomac_create_bpfdesc(struct ucred *cred, struct bpf_d *d,
1225     struct label *dlabel)
1226 {
1227 	struct mac_lomac *source, *dest;
1228 
1229 	source = SLOT(cred->cr_label);
1230 	dest = SLOT(dlabel);
1231 
1232 	mac_lomac_copy_single(source, dest);
1233 }
1234 
1235 static void
1236 mac_lomac_create_ifnet(struct ifnet *ifp, struct label *ifplabel)
1237 {
1238 	char tifname[IFNAMSIZ], *p, *q;
1239 	char tiflist[sizeof(trusted_interfaces)];
1240 	struct mac_lomac *dest;
1241 	int len, grade;
1242 
1243 	dest = SLOT(ifplabel);
1244 
1245 	if (ifp->if_type == IFT_LOOP) {
1246 		grade = MAC_LOMAC_TYPE_EQUAL;
1247 		goto set;
1248 	}
1249 
1250 	if (trust_all_interfaces) {
1251 		grade = MAC_LOMAC_TYPE_HIGH;
1252 		goto set;
1253 	}
1254 
1255 	grade = MAC_LOMAC_TYPE_LOW;
1256 
1257 	if (trusted_interfaces[0] == '\0' ||
1258 	    !strvalid(trusted_interfaces, sizeof(trusted_interfaces)))
1259 		goto set;
1260 
1261 	bzero(tiflist, sizeof(tiflist));
1262 	for (p = trusted_interfaces, q = tiflist; *p != '\0'; p++, q++)
1263 		if(*p != ' ' && *p != '\t')
1264 			*q = *p;
1265 
1266 	for (p = q = tiflist;; p++) {
1267 		if (*p == ',' || *p == '\0') {
1268 			len = p - q;
1269 			if (len < IFNAMSIZ) {
1270 				bzero(tifname, sizeof(tifname));
1271 				bcopy(q, tifname, len);
1272 				if (strcmp(tifname, ifp->if_xname) == 0) {
1273 					grade = MAC_LOMAC_TYPE_HIGH;
1274 					break;
1275 				}
1276 			}
1277 			else {
1278 				*p = '\0';
1279 				printf("MAC/LOMAC warning: interface name "
1280 				    "\"%s\" is too long (must be < %d)\n",
1281 				    q, IFNAMSIZ);
1282 			}
1283 			if (*p == '\0')
1284 				break;
1285 			q = p + 1;
1286 		}
1287 	}
1288 set:
1289 	mac_lomac_set_single(dest, grade, 0);
1290 	mac_lomac_set_range(dest, grade, 0, grade, 0);
1291 }
1292 
1293 static void
1294 mac_lomac_create_ipq(struct mbuf *m, struct label *mlabel, struct ipq *ipq,
1295     struct label *ipqlabel)
1296 {
1297 	struct mac_lomac *source, *dest;
1298 
1299 	source = SLOT(mlabel);
1300 	dest = SLOT(ipqlabel);
1301 
1302 	mac_lomac_copy_single(source, dest);
1303 }
1304 
1305 static void
1306 mac_lomac_create_datagram_from_ipq(struct ipq *ipq, struct label *ipqlabel,
1307     struct mbuf *m, struct label *mlabel)
1308 {
1309 	struct mac_lomac *source, *dest;
1310 
1311 	source = SLOT(ipqlabel);
1312 	dest = SLOT(mlabel);
1313 
1314 	/* Just use the head, since we require them all to match. */
1315 	mac_lomac_copy_single(source, dest);
1316 }
1317 
1318 static void
1319 mac_lomac_create_fragment(struct mbuf *m, struct label *mlabel,
1320     struct mbuf *frag, struct label *fraglabel)
1321 {
1322 	struct mac_lomac *source, *dest;
1323 
1324 	source = SLOT(mlabel);
1325 	dest = SLOT(fraglabel);
1326 
1327 	mac_lomac_copy_single(source, dest);
1328 }
1329 
1330 static void
1331 mac_lomac_create_mbuf_from_inpcb(struct inpcb *inp, struct label *inplabel,
1332     struct mbuf *m, struct label *mlabel)
1333 {
1334 	struct mac_lomac *source, *dest;
1335 
1336 	source = SLOT(inplabel);
1337 	dest = SLOT(mlabel);
1338 
1339 	mac_lomac_copy_single(source, dest);
1340 }
1341 
1342 static void
1343 mac_lomac_create_mbuf_linklayer(struct ifnet *ifp, struct label *ifplabel,
1344     struct mbuf *m, struct label *mlabel)
1345 {
1346 	struct mac_lomac *dest;
1347 
1348 	dest = SLOT(mlabel);
1349 
1350 	mac_lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
1351 }
1352 
1353 static void
1354 mac_lomac_create_mbuf_from_bpfdesc(struct bpf_d *d, struct label *dlabel,
1355     struct mbuf *m, struct label *mlabel)
1356 {
1357 	struct mac_lomac *source, *dest;
1358 
1359 	source = SLOT(dlabel);
1360 	dest = SLOT(mlabel);
1361 
1362 	mac_lomac_copy_single(source, dest);
1363 }
1364 
1365 static void
1366 mac_lomac_create_mbuf_from_ifnet(struct ifnet *ifp, struct label *ifplabel,
1367     struct mbuf *m, struct label *mlabel)
1368 {
1369 	struct mac_lomac *source, *dest;
1370 
1371 	source = SLOT(ifplabel);
1372 	dest = SLOT(mlabel);
1373 
1374 	mac_lomac_copy_single(source, dest);
1375 }
1376 
1377 static void
1378 mac_lomac_create_mbuf_multicast_encap(struct mbuf *m, struct label *mlabel,
1379     struct ifnet *ifp, struct label *ifplabel, struct mbuf *mnew,
1380     struct label *mnewlabel)
1381 {
1382 	struct mac_lomac *source, *dest;
1383 
1384 	source = SLOT(mlabel);
1385 	dest = SLOT(mnewlabel);
1386 
1387 	mac_lomac_copy_single(source, dest);
1388 }
1389 
1390 static void
1391 mac_lomac_create_mbuf_netlayer(struct mbuf *m, struct label *mlabel,
1392     struct mbuf *mnew, struct label *mnewlabel)
1393 {
1394 	struct mac_lomac *source, *dest;
1395 
1396 	source = SLOT(mlabel);
1397 	dest = SLOT(mnewlabel);
1398 
1399 	mac_lomac_copy_single(source, dest);
1400 }
1401 
1402 static int
1403 mac_lomac_fragment_match(struct mbuf *m, struct label *mlabel,
1404     struct ipq *ipq, struct label *ipqlabel)
1405 {
1406 	struct mac_lomac *a, *b;
1407 
1408 	a = SLOT(ipqlabel);
1409 	b = SLOT(mlabel);
1410 
1411 	return (mac_lomac_equal_single(a, b));
1412 }
1413 
1414 static void
1415 mac_lomac_relabel_ifnet(struct ucred *cred, struct ifnet *ifp,
1416     struct label *ifplabel, struct label *newlabel)
1417 {
1418 	struct mac_lomac *source, *dest;
1419 
1420 	source = SLOT(newlabel);
1421 	dest = SLOT(ifplabel);
1422 
1423 	try_relabel(source, dest);
1424 }
1425 
1426 static void
1427 mac_lomac_update_ipq(struct mbuf *m, struct label *mlabel, struct ipq *ipq,
1428     struct label *ipqlabel)
1429 {
1430 
1431 	/* NOOP: we only accept matching labels, so no need to update */
1432 }
1433 
1434 static void
1435 mac_lomac_inpcb_sosetlabel(struct socket *so, struct label *solabel,
1436     struct inpcb *inp, struct label *inplabel)
1437 {
1438 	struct mac_lomac *source, *dest;
1439 
1440 	source = SLOT(solabel);
1441 	dest = SLOT(inplabel);
1442 
1443 	mac_lomac_copy_single(source, dest);
1444 }
1445 
1446 static void
1447 mac_lomac_init_syncache_from_inpcb(struct label *label, struct inpcb *inp)
1448 {
1449 	struct mac_lomac *source, *dest;
1450 
1451 	source = SLOT(inp->inp_label);
1452 	dest = SLOT(label);
1453 	mac_lomac_copy(source, dest);
1454 }
1455 
1456 static void
1457 mac_lomac_create_mbuf_from_syncache(struct label *sc_label, struct mbuf *m,
1458     struct label *mlabel)
1459 {
1460 	struct mac_lomac *source, *dest;
1461 
1462 	source = SLOT(sc_label);
1463 	dest = SLOT(mlabel);
1464 	mac_lomac_copy(source, dest);
1465 }
1466 
1467 static void
1468 mac_lomac_create_mbuf_from_firewall(struct mbuf *m, struct label *mlabel)
1469 {
1470 	struct mac_lomac *dest;
1471 
1472 	dest = SLOT(mlabel);
1473 
1474 	/* XXX: where is the label for the firewall really comming from? */
1475 	mac_lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
1476 }
1477 
1478 /*
1479  * Labeling event operations: processes.
1480  */
1481 static void
1482 mac_lomac_execve_transition(struct ucred *old, struct ucred *new,
1483     struct vnode *vp, struct label *vplabel, struct label *interpvnodelabel,
1484     struct image_params *imgp, struct label *execlabel)
1485 {
1486 	struct mac_lomac *source, *dest, *obj, *robj;
1487 
1488 	source = SLOT(old->cr_label);
1489 	dest = SLOT(new->cr_label);
1490 	obj = SLOT(vplabel);
1491 	robj = interpvnodelabel != NULL ? SLOT(interpvnodelabel) : obj;
1492 
1493 	mac_lomac_copy(source, dest);
1494 	/*
1495 	 * If there's an auxiliary label on the real object, respect it
1496 	 * and assume that this level should be assumed immediately if
1497 	 * a higher level is currently in place.
1498 	 */
1499 	if (robj->ml_flags & MAC_LOMAC_FLAG_AUX &&
1500 	    !mac_lomac_dominate_element(&robj->ml_auxsingle, &dest->ml_single)
1501 	    && mac_lomac_auxsingle_in_range(robj, dest))
1502 		mac_lomac_set_single(dest, robj->ml_auxsingle.mle_type,
1503 		    robj->ml_auxsingle.mle_grade);
1504 	/*
1505 	 * Restructuring to use the execve transitioning mechanism
1506 	 * instead of the normal demotion mechanism here would be
1507 	 * difficult, so just copy the label over and perform standard
1508 	 * demotion.  This is also non-optimal because it will result
1509 	 * in the intermediate label "new" being created and immediately
1510 	 * recycled.
1511 	 */
1512 	if (mac_lomac_enabled && revocation_enabled &&
1513 	    !mac_lomac_dominate_single(obj, source))
1514 		(void)maybe_demote(source, obj, "executing", "file", vp);
1515 }
1516 
1517 static int
1518 mac_lomac_execve_will_transition(struct ucred *old, struct vnode *vp,
1519     struct label *vplabel, struct label *interpvnodelabel,
1520     struct image_params *imgp, struct label *execlabel)
1521 {
1522 	struct mac_lomac *subj, *obj, *robj;
1523 
1524 	if (!mac_lomac_enabled || !revocation_enabled)
1525 		return (0);
1526 
1527 	subj = SLOT(old->cr_label);
1528 	obj = SLOT(vplabel);
1529 	robj = interpvnodelabel != NULL ? SLOT(interpvnodelabel) : obj;
1530 
1531 	return ((robj->ml_flags & MAC_LOMAC_FLAG_AUX &&
1532 	    !mac_lomac_dominate_element(&robj->ml_auxsingle, &subj->ml_single)
1533 	    && mac_lomac_auxsingle_in_range(robj, subj)) ||
1534 	    !mac_lomac_dominate_single(obj, subj));
1535 }
1536 
1537 static void
1538 mac_lomac_create_proc0(struct ucred *cred)
1539 {
1540 	struct mac_lomac *dest;
1541 
1542 	dest = SLOT(cred->cr_label);
1543 
1544 	mac_lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
1545 	mac_lomac_set_range(dest, MAC_LOMAC_TYPE_LOW, 0, MAC_LOMAC_TYPE_HIGH,
1546 	    0);
1547 }
1548 
1549 static void
1550 mac_lomac_create_proc1(struct ucred *cred)
1551 {
1552 	struct mac_lomac *dest;
1553 
1554 	dest = SLOT(cred->cr_label);
1555 
1556 	mac_lomac_set_single(dest, MAC_LOMAC_TYPE_HIGH, 0);
1557 	mac_lomac_set_range(dest, MAC_LOMAC_TYPE_LOW, 0, MAC_LOMAC_TYPE_HIGH,
1558 	    0);
1559 }
1560 
1561 static void
1562 mac_lomac_relabel_cred(struct ucred *cred, struct label *newlabel)
1563 {
1564 	struct mac_lomac *source, *dest;
1565 
1566 	source = SLOT(newlabel);
1567 	dest = SLOT(cred->cr_label);
1568 
1569 	try_relabel(source, dest);
1570 }
1571 
1572 /*
1573  * Access control checks.
1574  */
1575 static int
1576 mac_lomac_check_bpfdesc_receive(struct bpf_d *d, struct label *dlabel,
1577     struct ifnet *ifp, struct label *ifplabel)
1578 {
1579 	struct mac_lomac *a, *b;
1580 
1581 	if (!mac_lomac_enabled)
1582 		return (0);
1583 
1584 	a = SLOT(dlabel);
1585 	b = SLOT(ifplabel);
1586 
1587 	if (mac_lomac_equal_single(a, b))
1588 		return (0);
1589 	return (EACCES);
1590 }
1591 
1592 static int
1593 mac_lomac_check_cred_relabel(struct ucred *cred, struct label *newlabel)
1594 {
1595 	struct mac_lomac *subj, *new;
1596 	int error;
1597 
1598 	subj = SLOT(cred->cr_label);
1599 	new = SLOT(newlabel);
1600 
1601 	/*
1602 	 * If there is a LOMAC label update for the credential, it may
1603 	 * be an update of the single, range, or both.
1604 	 */
1605 	error = lomac_atmostflags(new, MAC_LOMAC_FLAGS_BOTH);
1606 	if (error)
1607 		return (error);
1608 
1609 	/*
1610 	 * If the LOMAC label is to be changed, authorize as appropriate.
1611 	 */
1612 	if (new->ml_flags & MAC_LOMAC_FLAGS_BOTH) {
1613 		/*
1614 		 * Fill in the missing parts from the previous label.
1615 		 */
1616 		if ((new->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
1617 			mac_lomac_copy_single(subj, new);
1618 		if ((new->ml_flags & MAC_LOMAC_FLAG_RANGE) == 0)
1619 			mac_lomac_copy_range(subj, new);
1620 
1621 		/*
1622 		 * To change the LOMAC range on a credential, the new
1623 		 * range label must be in the current range.
1624 		 */
1625 		if (!mac_lomac_range_in_range(new, subj))
1626 			return (EPERM);
1627 
1628 		/*
1629 		 * To change the LOMAC single label on a credential, the
1630 		 * new single label must be in the new range.  Implicitly
1631 		 * from the previous check, the new single is in the old
1632 		 * range.
1633 		 */
1634 		if (!mac_lomac_single_in_range(new, new))
1635 			return (EPERM);
1636 
1637 		/*
1638 		 * To have EQUAL in any component of the new credential
1639 		 * LOMAC label, the subject must already have EQUAL in
1640 		 * their label.
1641 		 */
1642 		if (mac_lomac_contains_equal(new)) {
1643 			error = mac_lomac_subject_privileged(subj);
1644 			if (error)
1645 				return (error);
1646 		}
1647 
1648 		/*
1649 		 * XXXMAC: Additional consistency tests regarding the
1650 		 * single and range of the new label might be performed
1651 		 * here.
1652 		 */
1653 	}
1654 
1655 	return (0);
1656 }
1657 
1658 static int
1659 mac_lomac_check_cred_visible(struct ucred *cr1, struct ucred *cr2)
1660 {
1661 	struct mac_lomac *subj, *obj;
1662 
1663 	if (!mac_lomac_enabled)
1664 		return (0);
1665 
1666 	subj = SLOT(cr1->cr_label);
1667 	obj = SLOT(cr2->cr_label);
1668 
1669 	/* XXX: range */
1670 	if (!mac_lomac_dominate_single(obj, subj))
1671 		return (ESRCH);
1672 
1673 	return (0);
1674 }
1675 
1676 static int
1677 mac_lomac_check_ifnet_relabel(struct ucred *cred, struct ifnet *ifp,
1678     struct label *ifplabel, struct label *newlabel)
1679 {
1680 	struct mac_lomac *subj, *new;
1681 	int error;
1682 
1683 	subj = SLOT(cred->cr_label);
1684 	new = SLOT(newlabel);
1685 
1686 	/*
1687 	 * If there is a LOMAC label update for the interface, it may
1688 	 * be an update of the single, range, or both.
1689 	 */
1690 	error = lomac_atmostflags(new, MAC_LOMAC_FLAGS_BOTH);
1691 	if (error)
1692 		return (error);
1693 
1694 	/*
1695 	 * Relabling network interfaces requires LOMAC privilege.
1696 	 */
1697 	error = mac_lomac_subject_privileged(subj);
1698 	if (error)
1699 		return (error);
1700 
1701 	/*
1702 	 * If the LOMAC label is to be changed, authorize as appropriate.
1703 	 */
1704 	if (new->ml_flags & MAC_LOMAC_FLAGS_BOTH) {
1705 		/*
1706 		 * Fill in the missing parts from the previous label.
1707 		 */
1708 		if ((new->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
1709 			mac_lomac_copy_single(subj, new);
1710 		if ((new->ml_flags & MAC_LOMAC_FLAG_RANGE) == 0)
1711 			mac_lomac_copy_range(subj, new);
1712 
1713 		/*
1714 		 * Rely on the traditional superuser status for the LOMAC
1715 		 * interface relabel requirements.  XXXMAC: This will go
1716 		 * away.
1717 		 *
1718 		 * XXXRW: This is also redundant to a higher layer check.
1719 		 */
1720 		error = priv_check_cred(cred, PRIV_NET_SETIFMAC, 0);
1721 		if (error)
1722 			return (EPERM);
1723 
1724 		/*
1725 		 * XXXMAC: Additional consistency tests regarding the single
1726 		 * and the range of the new label might be performed here.
1727 		 */
1728 	}
1729 
1730 	return (0);
1731 }
1732 
1733 static int
1734 mac_lomac_check_ifnet_transmit(struct ifnet *ifp, struct label *ifplabel,
1735     struct mbuf *m, struct label *mlabel)
1736 {
1737 	struct mac_lomac *p, *i;
1738 
1739 	if (!mac_lomac_enabled)
1740 		return (0);
1741 
1742 	p = SLOT(mlabel);
1743 	i = SLOT(ifplabel);
1744 
1745 	return (mac_lomac_single_in_range(p, i) ? 0 : EACCES);
1746 }
1747 
1748 static int
1749 mac_lomac_check_inpcb_deliver(struct inpcb *inp, struct label *inplabel,
1750     struct mbuf *m, struct label *mlabel)
1751 {
1752 	struct mac_lomac *p, *i;
1753 
1754 	if (!mac_lomac_enabled)
1755 		return (0);
1756 
1757 	p = SLOT(mlabel);
1758 	i = SLOT(inplabel);
1759 
1760 	return (mac_lomac_equal_single(p, i) ? 0 : EACCES);
1761 }
1762 
1763 static int
1764 mac_lomac_check_kld_load(struct ucred *cred, struct vnode *vp,
1765     struct label *vplabel)
1766 {
1767 	struct mac_lomac *subj, *obj;
1768 
1769 	if (!mac_lomac_enabled)
1770 		return (0);
1771 
1772 	subj = SLOT(cred->cr_label);
1773 	obj = SLOT(vplabel);
1774 
1775 	if (mac_lomac_subject_privileged(subj))
1776 		return (EPERM);
1777 
1778 	if (!mac_lomac_high_single(obj))
1779 		return (EACCES);
1780 
1781 	return (0);
1782 }
1783 
1784 static int
1785 mac_lomac_check_pipe_ioctl(struct ucred *cred, struct pipepair *pp,
1786     struct label *pplabel, unsigned long cmd, void /* caddr_t */ *data)
1787 {
1788 
1789 	if (!mac_lomac_enabled)
1790 		return (0);
1791 
1792 	/* XXX: This will be implemented soon... */
1793 
1794 	return (0);
1795 }
1796 
1797 static int
1798 mac_lomac_check_pipe_read(struct ucred *cred, struct pipepair *pp,
1799     struct label *pplabel)
1800 {
1801 	struct mac_lomac *subj, *obj;
1802 
1803 	if (!mac_lomac_enabled)
1804 		return (0);
1805 
1806 	subj = SLOT(cred->cr_label);
1807 	obj = SLOT(pplabel);
1808 
1809 	if (!mac_lomac_dominate_single(obj, subj))
1810 		return (maybe_demote(subj, obj, "reading", "pipe", NULL));
1811 
1812 	return (0);
1813 }
1814 
1815 static int
1816 mac_lomac_check_pipe_relabel(struct ucred *cred, struct pipepair *pp,
1817     struct label *pplabel, struct label *newlabel)
1818 {
1819 	struct mac_lomac *subj, *obj, *new;
1820 	int error;
1821 
1822 	new = SLOT(newlabel);
1823 	subj = SLOT(cred->cr_label);
1824 	obj = SLOT(pplabel);
1825 
1826 	/*
1827 	 * If there is a LOMAC label update for a pipe, it must be a
1828 	 * single update.
1829 	 */
1830 	error = lomac_atmostflags(new, MAC_LOMAC_FLAG_SINGLE);
1831 	if (error)
1832 		return (error);
1833 
1834 	/*
1835 	 * To perform a relabel of a pipe (LOMAC label or not), LOMAC must
1836 	 * authorize the relabel.
1837 	 */
1838 	if (!mac_lomac_single_in_range(obj, subj))
1839 		return (EPERM);
1840 
1841 	/*
1842 	 * If the LOMAC label is to be changed, authorize as appropriate.
1843 	 */
1844 	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
1845 		/*
1846 		 * To change the LOMAC label on a pipe, the new pipe label
1847 		 * must be in the subject range.
1848 		 */
1849 		if (!mac_lomac_single_in_range(new, subj))
1850 			return (EPERM);
1851 
1852 		/*
1853 		 * To change the LOMAC label on a pipe to be EQUAL, the
1854 		 * subject must have appropriate privilege.
1855 		 */
1856 		if (mac_lomac_contains_equal(new)) {
1857 			error = mac_lomac_subject_privileged(subj);
1858 			if (error)
1859 				return (error);
1860 		}
1861 	}
1862 
1863 	return (0);
1864 }
1865 
1866 static int
1867 mac_lomac_check_pipe_write(struct ucred *cred, struct pipepair *pp,
1868     struct label *pplabel)
1869 {
1870 	struct mac_lomac *subj, *obj;
1871 
1872 	if (!mac_lomac_enabled)
1873 		return (0);
1874 
1875 	subj = SLOT(cred->cr_label);
1876 	obj = SLOT(pplabel);
1877 
1878 	if (!mac_lomac_subject_dominate(subj, obj))
1879 		return (EACCES);
1880 
1881 	return (0);
1882 }
1883 
1884 static int
1885 mac_lomac_check_proc_debug(struct ucred *cred, struct proc *p)
1886 {
1887 	struct mac_lomac *subj, *obj;
1888 
1889 	if (!mac_lomac_enabled)
1890 		return (0);
1891 
1892 	subj = SLOT(cred->cr_label);
1893 	obj = SLOT(p->p_ucred->cr_label);
1894 
1895 	/* XXX: range checks */
1896 	if (!mac_lomac_dominate_single(obj, subj))
1897 		return (ESRCH);
1898 	if (!mac_lomac_subject_dominate(subj, obj))
1899 		return (EACCES);
1900 
1901 	return (0);
1902 }
1903 
1904 static int
1905 mac_lomac_check_proc_sched(struct ucred *cred, struct proc *p)
1906 {
1907 	struct mac_lomac *subj, *obj;
1908 
1909 	if (!mac_lomac_enabled)
1910 		return (0);
1911 
1912 	subj = SLOT(cred->cr_label);
1913 	obj = SLOT(p->p_ucred->cr_label);
1914 
1915 	/* XXX: range checks */
1916 	if (!mac_lomac_dominate_single(obj, subj))
1917 		return (ESRCH);
1918 	if (!mac_lomac_subject_dominate(subj, obj))
1919 		return (EACCES);
1920 
1921 	return (0);
1922 }
1923 
1924 static int
1925 mac_lomac_check_proc_signal(struct ucred *cred, struct proc *p, int signum)
1926 {
1927 	struct mac_lomac *subj, *obj;
1928 
1929 	if (!mac_lomac_enabled)
1930 		return (0);
1931 
1932 	subj = SLOT(cred->cr_label);
1933 	obj = SLOT(p->p_ucred->cr_label);
1934 
1935 	/* XXX: range checks */
1936 	if (!mac_lomac_dominate_single(obj, subj))
1937 		return (ESRCH);
1938 	if (!mac_lomac_subject_dominate(subj, obj))
1939 		return (EACCES);
1940 
1941 	return (0);
1942 }
1943 
1944 static int
1945 mac_lomac_check_socket_deliver(struct socket *so, struct label *solabel,
1946     struct mbuf *m, struct label *mlabel)
1947 {
1948 	struct mac_lomac *p, *s;
1949 
1950 	if (!mac_lomac_enabled)
1951 		return (0);
1952 
1953 	p = SLOT(mlabel);
1954 	s = SLOT(solabel);
1955 
1956 	return (mac_lomac_equal_single(p, s) ? 0 : EACCES);
1957 }
1958 
1959 static int
1960 mac_lomac_check_socket_relabel(struct ucred *cred, struct socket *so,
1961     struct label *solabel, struct label *newlabel)
1962 {
1963 	struct mac_lomac *subj, *obj, *new;
1964 	int error;
1965 
1966 	new = SLOT(newlabel);
1967 	subj = SLOT(cred->cr_label);
1968 	obj = SLOT(solabel);
1969 
1970 	/*
1971 	 * If there is a LOMAC label update for the socket, it may be
1972 	 * an update of single.
1973 	 */
1974 	error = lomac_atmostflags(new, MAC_LOMAC_FLAG_SINGLE);
1975 	if (error)
1976 		return (error);
1977 
1978 	/*
1979 	 * To relabel a socket, the old socket single must be in the subject
1980 	 * range.
1981 	 */
1982 	if (!mac_lomac_single_in_range(obj, subj))
1983 		return (EPERM);
1984 
1985 	/*
1986 	 * If the LOMAC label is to be changed, authorize as appropriate.
1987 	 */
1988 	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
1989 		/*
1990 		 * To relabel a socket, the new socket single must be in
1991 		 * the subject range.
1992 		 */
1993 		if (!mac_lomac_single_in_range(new, subj))
1994 			return (EPERM);
1995 
1996 		/*
1997 		 * To change the LOMAC label on the socket to contain EQUAL,
1998 		 * the subject must have appropriate privilege.
1999 		 */
2000 		if (mac_lomac_contains_equal(new)) {
2001 			error = mac_lomac_subject_privileged(subj);
2002 			if (error)
2003 				return (error);
2004 		}
2005 	}
2006 
2007 	return (0);
2008 }
2009 
2010 static int
2011 mac_lomac_check_socket_visible(struct ucred *cred, struct socket *so,
2012     struct label *solabel)
2013 {
2014 	struct mac_lomac *subj, *obj;
2015 
2016 	if (!mac_lomac_enabled)
2017 		return (0);
2018 
2019 	subj = SLOT(cred->cr_label);
2020 	obj = SLOT(solabel);
2021 
2022 	if (!mac_lomac_dominate_single(obj, subj))
2023 		return (ENOENT);
2024 
2025 	return (0);
2026 }
2027 
2028 /*
2029  * Some system privileges are allowed regardless of integrity grade; others
2030  * are allowed only when running with privilege with respect to the LOMAC
2031  * policy as they might otherwise allow bypassing of the integrity policy.
2032  */
2033 static int
2034 mac_lomac_priv_check(struct ucred *cred, int priv)
2035 {
2036 	struct mac_lomac *subj;
2037 	int error;
2038 
2039 	if (!mac_lomac_enabled)
2040 		return (0);
2041 
2042 	/*
2043 	 * Exempt only specific privileges from the LOMAC integrity policy.
2044 	 */
2045 	switch (priv) {
2046 	case PRIV_KTRACE:
2047 	case PRIV_MSGBUF:
2048 
2049 	/*
2050 	 * Allow processes to manipulate basic process audit properties, and
2051 	 * to submit audit records.
2052 	 */
2053 	case PRIV_AUDIT_GETAUDIT:
2054 	case PRIV_AUDIT_SETAUDIT:
2055 	case PRIV_AUDIT_SUBMIT:
2056 
2057 	/*
2058 	 * Allow processes to manipulate their regular UNIX credentials.
2059 	 */
2060 	case PRIV_CRED_SETUID:
2061 	case PRIV_CRED_SETEUID:
2062 	case PRIV_CRED_SETGID:
2063 	case PRIV_CRED_SETEGID:
2064 	case PRIV_CRED_SETGROUPS:
2065 	case PRIV_CRED_SETREUID:
2066 	case PRIV_CRED_SETREGID:
2067 	case PRIV_CRED_SETRESUID:
2068 	case PRIV_CRED_SETRESGID:
2069 
2070 	/*
2071 	 * Allow processes to perform system monitoring.
2072 	 */
2073 	case PRIV_SEEOTHERGIDS:
2074 	case PRIV_SEEOTHERUIDS:
2075 		break;
2076 
2077 	/*
2078 	 * Allow access to general process debugging facilities.  We
2079 	 * separately control debugging based on MAC label.
2080 	 */
2081 	case PRIV_DEBUG_DIFFCRED:
2082 	case PRIV_DEBUG_SUGID:
2083 	case PRIV_DEBUG_UNPRIV:
2084 
2085 	/*
2086 	 * Allow manipulating jails.
2087 	 */
2088 	case PRIV_JAIL_ATTACH:
2089 
2090 	/*
2091 	 * Allow privilege with respect to the Partition policy, but not the
2092 	 * Privs policy.
2093 	 */
2094 	case PRIV_MAC_PARTITION:
2095 
2096 	/*
2097 	 * Allow privilege with respect to process resource limits and login
2098 	 * context.
2099 	 */
2100 	case PRIV_PROC_LIMIT:
2101 	case PRIV_PROC_SETLOGIN:
2102 	case PRIV_PROC_SETRLIMIT:
2103 
2104 	/*
2105 	 * Allow System V and POSIX IPC privileges.
2106 	 */
2107 	case PRIV_IPC_READ:
2108 	case PRIV_IPC_WRITE:
2109 	case PRIV_IPC_ADMIN:
2110 	case PRIV_IPC_MSGSIZE:
2111 	case PRIV_MQ_ADMIN:
2112 
2113 	/*
2114 	 * Allow certain scheduler manipulations -- possibly this should be
2115 	 * controlled by more fine-grained policy, as potentially low
2116 	 * integrity processes can deny CPU to higher integrity ones.
2117 	 */
2118 	case PRIV_SCHED_DIFFCRED:
2119 	case PRIV_SCHED_SETPRIORITY:
2120 	case PRIV_SCHED_RTPRIO:
2121 	case PRIV_SCHED_SETPOLICY:
2122 	case PRIV_SCHED_SET:
2123 	case PRIV_SCHED_SETPARAM:
2124 
2125 	/*
2126 	 * More IPC privileges.
2127 	 */
2128 	case PRIV_SEM_WRITE:
2129 
2130 	/*
2131 	 * Allow signaling privileges subject to integrity policy.
2132 	 */
2133 	case PRIV_SIGNAL_DIFFCRED:
2134 	case PRIV_SIGNAL_SUGID:
2135 
2136 	/*
2137 	 * Allow access to only limited sysctls from lower integrity levels;
2138 	 * piggy-back on the Jail definition.
2139 	 */
2140 	case PRIV_SYSCTL_WRITEJAIL:
2141 
2142 	/*
2143 	 * Allow TTY-based privileges, subject to general device access using
2144 	 * labels on TTY device nodes, but not console privilege.
2145 	 */
2146 	case PRIV_TTY_DRAINWAIT:
2147 	case PRIV_TTY_DTRWAIT:
2148 	case PRIV_TTY_EXCLUSIVE:
2149 	case PRIV_TTY_PRISON:
2150 	case PRIV_TTY_STI:
2151 	case PRIV_TTY_SETA:
2152 
2153 	/*
2154 	 * Grant most VFS privileges, as almost all are in practice bounded
2155 	 * by more specific checks using labels.
2156 	 */
2157 	case PRIV_VFS_READ:
2158 	case PRIV_VFS_WRITE:
2159 	case PRIV_VFS_ADMIN:
2160 	case PRIV_VFS_EXEC:
2161 	case PRIV_VFS_LOOKUP:
2162 	case PRIV_VFS_CHFLAGS_DEV:
2163 	case PRIV_VFS_CHOWN:
2164 	case PRIV_VFS_CHROOT:
2165 	case PRIV_VFS_RETAINSUGID:
2166 	case PRIV_VFS_EXCEEDQUOTA:
2167 	case PRIV_VFS_FCHROOT:
2168 	case PRIV_VFS_FHOPEN:
2169 	case PRIV_VFS_FHSTATFS:
2170 	case PRIV_VFS_GENERATION:
2171 	case PRIV_VFS_GETFH:
2172 	case PRIV_VFS_GETQUOTA:
2173 	case PRIV_VFS_LINK:
2174 	case PRIV_VFS_MOUNT:
2175 	case PRIV_VFS_MOUNT_OWNER:
2176 	case PRIV_VFS_MOUNT_PERM:
2177 	case PRIV_VFS_MOUNT_SUIDDIR:
2178 	case PRIV_VFS_MOUNT_NONUSER:
2179 	case PRIV_VFS_SETGID:
2180 	case PRIV_VFS_STICKYFILE:
2181 	case PRIV_VFS_SYSFLAGS:
2182 	case PRIV_VFS_UNMOUNT:
2183 
2184 	/*
2185 	 * Allow VM privileges; it would be nice if these were subject to
2186 	 * resource limits.
2187 	 */
2188 	case PRIV_VM_MADV_PROTECT:
2189 	case PRIV_VM_MLOCK:
2190 	case PRIV_VM_MUNLOCK:
2191 
2192 	/*
2193 	 * Allow some but not all network privileges.  In general, dont allow
2194 	 * reconfiguring the network stack, just normal use.
2195 	 */
2196 	case PRIV_NETATALK_RESERVEDPORT:
2197 	case PRIV_NETINET_RESERVEDPORT:
2198 	case PRIV_NETINET_RAW:
2199 	case PRIV_NETINET_REUSEPORT:
2200 	case PRIV_NETIPX_RESERVEDPORT:
2201 	case PRIV_NETIPX_RAW:
2202 		break;
2203 
2204 	/*
2205 	 * All remaining system privileges are allow only if the process
2206 	 * holds privilege with respect to the LOMAC policy.
2207 	 */
2208 	default:
2209 		subj = SLOT(cred->cr_label);
2210 		error = mac_lomac_subject_privileged(subj);
2211 		if (error)
2212 			return (error);
2213 	}
2214 	return (0);
2215 }
2216 
2217 
2218 static int
2219 mac_lomac_check_system_acct(struct ucred *cred, struct vnode *vp,
2220     struct label *vplabel)
2221 {
2222 	struct mac_lomac *subj, *obj;
2223 
2224 	if (!mac_lomac_enabled)
2225 		return (0);
2226 
2227 	subj = SLOT(cred->cr_label);
2228 	obj = SLOT(vplabel);
2229 
2230 	if (mac_lomac_subject_privileged(subj))
2231 		return (EPERM);
2232 
2233 	if (!mac_lomac_high_single(obj))
2234 		return (EACCES);
2235 
2236 	return (0);
2237 }
2238 
2239 static int
2240 mac_lomac_check_system_auditctl(struct ucred *cred, struct vnode *vp,
2241     struct label *vplabel)
2242 {
2243 	struct mac_lomac *subj, *obj;
2244 
2245 	if (!mac_lomac_enabled)
2246 		return (0);
2247 
2248 	subj = SLOT(cred->cr_label);
2249 	obj = SLOT(vplabel);
2250 
2251 	if (mac_lomac_subject_privileged(subj))
2252 		return (EPERM);
2253 
2254 	if (!mac_lomac_high_single(obj))
2255 		return (EACCES);
2256 
2257 	return (0);
2258 }
2259 
2260 static int
2261 mac_lomac_check_system_swapoff(struct ucred *cred, struct vnode *vp,
2262     struct label *vplabel)
2263 {
2264 	struct mac_lomac *subj;
2265 
2266 	if (!mac_lomac_enabled)
2267 		return (0);
2268 
2269 	subj = SLOT(cred->cr_label);
2270 
2271 	if (mac_lomac_subject_privileged(subj))
2272 		return (EPERM);
2273 
2274 	return (0);
2275 }
2276 
2277 static int
2278 mac_lomac_check_system_swapon(struct ucred *cred, struct vnode *vp,
2279     struct label *vplabel)
2280 {
2281 	struct mac_lomac *subj, *obj;
2282 
2283 	if (!mac_lomac_enabled)
2284 		return (0);
2285 
2286 	subj = SLOT(cred->cr_label);
2287 	obj = SLOT(vplabel);
2288 
2289 	if (mac_lomac_subject_privileged(subj))
2290 		return (EPERM);
2291 
2292 	if (!mac_lomac_high_single(obj))
2293 		return (EACCES);
2294 
2295 	return (0);
2296 }
2297 
2298 static int
2299 mac_lomac_check_system_sysctl(struct ucred *cred, struct sysctl_oid *oidp,
2300     void *arg1, int arg2, struct sysctl_req *req)
2301 {
2302 	struct mac_lomac *subj;
2303 
2304 	if (!mac_lomac_enabled)
2305 		return (0);
2306 
2307 	subj = SLOT(cred->cr_label);
2308 
2309 	/*
2310 	 * Treat sysctl variables without CTLFLAG_ANYBODY flag as
2311 	 * lomac/high, but also require privilege to change them.
2312 	 */
2313 	if (req->newptr != NULL && (oidp->oid_kind & CTLFLAG_ANYBODY) == 0) {
2314 #ifdef notdef
2315 		if (!mac_lomac_subject_dominate_high(subj))
2316 			return (EACCES);
2317 #endif
2318 
2319 		if (mac_lomac_subject_privileged(subj))
2320 			return (EPERM);
2321 	}
2322 
2323 	return (0);
2324 }
2325 
2326 static int
2327 mac_lomac_check_vnode_create(struct ucred *cred, struct vnode *dvp,
2328     struct label *dvplabel, struct componentname *cnp, struct vattr *vap)
2329 {
2330 	struct mac_lomac *subj, *obj;
2331 
2332 	if (!mac_lomac_enabled)
2333 		return (0);
2334 
2335 	subj = SLOT(cred->cr_label);
2336 	obj = SLOT(dvplabel);
2337 
2338 	if (!mac_lomac_subject_dominate(subj, obj))
2339 		return (EACCES);
2340 	if (obj->ml_flags & MAC_LOMAC_FLAG_AUX &&
2341 	    !mac_lomac_dominate_element(&subj->ml_single, &obj->ml_auxsingle))
2342 		return (EACCES);
2343 
2344 	return (0);
2345 }
2346 
2347 static int
2348 mac_lomac_check_vnode_deleteacl(struct ucred *cred, struct vnode *vp,
2349     struct label *vplabel, acl_type_t type)
2350 {
2351 	struct mac_lomac *subj, *obj;
2352 
2353 	if (!mac_lomac_enabled)
2354 		return (0);
2355 
2356 	subj = SLOT(cred->cr_label);
2357 	obj = SLOT(vplabel);
2358 
2359 	if (!mac_lomac_subject_dominate(subj, obj))
2360 		return (EACCES);
2361 
2362 	return (0);
2363 }
2364 
2365 static int
2366 mac_lomac_check_vnode_link(struct ucred *cred, struct vnode *dvp,
2367     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2368     struct componentname *cnp)
2369 {
2370 	struct mac_lomac *subj, *obj;
2371 
2372 	if (!mac_lomac_enabled)
2373 		return (0);
2374 
2375 	subj = SLOT(cred->cr_label);
2376 	obj = SLOT(dvplabel);
2377 
2378 	if (!mac_lomac_subject_dominate(subj, obj))
2379 		return (EACCES);
2380 
2381 	obj = SLOT(vplabel);
2382 
2383 	if (!mac_lomac_subject_dominate(subj, obj))
2384 		return (EACCES);
2385 
2386 	return (0);
2387 }
2388 
2389 static int
2390 mac_lomac_check_vnode_mmap(struct ucred *cred, struct vnode *vp,
2391     struct label *vplabel, int prot, int flags)
2392 {
2393 	struct mac_lomac *subj, *obj;
2394 
2395 	/*
2396 	 * Rely on the use of open()-time protections to handle
2397 	 * non-revocation cases.
2398 	 */
2399 	if (!mac_lomac_enabled)
2400 		return (0);
2401 
2402 	subj = SLOT(cred->cr_label);
2403 	obj = SLOT(vplabel);
2404 
2405 	if (((prot & VM_PROT_WRITE) != 0) && ((flags & MAP_SHARED) != 0)) {
2406 		if (!mac_lomac_subject_dominate(subj, obj))
2407 			return (EACCES);
2408 	}
2409 	if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
2410 		if (!mac_lomac_dominate_single(obj, subj))
2411 			return (maybe_demote(subj, obj, "mapping", "file", vp));
2412 	}
2413 
2414 	return (0);
2415 }
2416 
2417 static void
2418 mac_lomac_check_vnode_mmap_downgrade(struct ucred *cred, struct vnode *vp,
2419     struct label *vplabel, /* XXX vm_prot_t */ int *prot)
2420 {
2421 	struct mac_lomac *subj, *obj;
2422 
2423 	/*
2424 	 * Rely on the use of open()-time protections to handle
2425 	 * non-revocation cases.
2426 	 */
2427 	if (!mac_lomac_enabled || !revocation_enabled)
2428 		return;
2429 
2430 	subj = SLOT(cred->cr_label);
2431 	obj = SLOT(vplabel);
2432 
2433 	if (!mac_lomac_subject_dominate(subj, obj))
2434 		*prot &= ~VM_PROT_WRITE;
2435 }
2436 
2437 static int
2438 mac_lomac_check_vnode_open(struct ucred *cred, struct vnode *vp,
2439     struct label *vplabel, int acc_mode)
2440 {
2441 	struct mac_lomac *subj, *obj;
2442 
2443 	if (!mac_lomac_enabled)
2444 		return (0);
2445 
2446 	subj = SLOT(cred->cr_label);
2447 	obj = SLOT(vplabel);
2448 
2449 	/* XXX privilege override for admin? */
2450 	if (acc_mode & (VWRITE | VAPPEND | VADMIN)) {
2451 		if (!mac_lomac_subject_dominate(subj, obj))
2452 			return (EACCES);
2453 	}
2454 
2455 	return (0);
2456 }
2457 
2458 static int
2459 mac_lomac_check_vnode_read(struct ucred *active_cred, struct ucred *file_cred,
2460     struct vnode *vp, struct label *vplabel)
2461 {
2462 	struct mac_lomac *subj, *obj;
2463 
2464 	if (!mac_lomac_enabled || !revocation_enabled)
2465 		return (0);
2466 
2467 	subj = SLOT(active_cred->cr_label);
2468 	obj = SLOT(vplabel);
2469 
2470 	if (!mac_lomac_dominate_single(obj, subj))
2471 		return (maybe_demote(subj, obj, "reading", "file", vp));
2472 
2473 	return (0);
2474 }
2475 
2476 static int
2477 mac_lomac_check_vnode_relabel(struct ucred *cred, struct vnode *vp,
2478     struct label *vplabel, struct label *newlabel)
2479 {
2480 	struct mac_lomac *old, *new, *subj;
2481 	int error;
2482 
2483 	old = SLOT(vplabel);
2484 	new = SLOT(newlabel);
2485 	subj = SLOT(cred->cr_label);
2486 
2487 	/*
2488 	 * If there is a LOMAC label update for the vnode, it must be a
2489 	 * single label, with an optional explicit auxiliary single.
2490 	 */
2491 	error = lomac_atmostflags(new,
2492 	    MAC_LOMAC_FLAG_SINGLE | MAC_LOMAC_FLAG_AUX);
2493 	if (error)
2494 		return (error);
2495 
2496 	/*
2497 	 * To perform a relabel of the vnode (LOMAC label or not), LOMAC must
2498 	 * authorize the relabel.
2499 	 */
2500 	if (!mac_lomac_single_in_range(old, subj))
2501 		return (EPERM);
2502 
2503 	/*
2504 	 * If the LOMAC label is to be changed, authorize as appropriate.
2505 	 */
2506 	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
2507 		/*
2508 		 * To change the LOMAC label on a vnode, the new vnode label
2509 		 * must be in the subject range.
2510 		 */
2511 		if (!mac_lomac_single_in_range(new, subj))
2512 			return (EPERM);
2513 
2514 		/*
2515 		 * To change the LOMAC label on the vnode to be EQUAL,
2516 		 * the subject must have appropriate privilege.
2517 		 */
2518 		if (mac_lomac_contains_equal(new)) {
2519 			error = mac_lomac_subject_privileged(subj);
2520 			if (error)
2521 				return (error);
2522 		}
2523 	}
2524 	if (new->ml_flags & MAC_LOMAC_FLAG_AUX) {
2525 		/*
2526 		 * Fill in the missing parts from the previous label.
2527 		 */
2528 		if ((new->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
2529 			mac_lomac_copy_single(subj, new);
2530 
2531 		/*
2532 		 * To change the auxiliary LOMAC label on a vnode, the new
2533 		 * vnode label must be in the subject range.
2534 		 */
2535 		if (!mac_lomac_auxsingle_in_range(new, subj))
2536 			return (EPERM);
2537 
2538 		/*
2539 		 * To change the auxiliary LOMAC label on the vnode to be
2540 		 * EQUAL, the subject must have appropriate privilege.
2541 		 */
2542 		if (mac_lomac_contains_equal(new)) {
2543 			error = mac_lomac_subject_privileged(subj);
2544 			if (error)
2545 				return (error);
2546 		}
2547 	}
2548 
2549 	return (0);
2550 }
2551 
2552 static int
2553 mac_lomac_check_vnode_rename_from(struct ucred *cred, struct vnode *dvp,
2554     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2555     struct componentname *cnp)
2556 {
2557 	struct mac_lomac *subj, *obj;
2558 
2559 	if (!mac_lomac_enabled)
2560 		return (0);
2561 
2562 	subj = SLOT(cred->cr_label);
2563 	obj = SLOT(dvplabel);
2564 
2565 	if (!mac_lomac_subject_dominate(subj, obj))
2566 		return (EACCES);
2567 
2568 	obj = SLOT(vplabel);
2569 
2570 	if (!mac_lomac_subject_dominate(subj, obj))
2571 		return (EACCES);
2572 
2573 	return (0);
2574 }
2575 
2576 static int
2577 mac_lomac_check_vnode_rename_to(struct ucred *cred, struct vnode *dvp,
2578     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2579     int samedir, struct componentname *cnp)
2580 {
2581 	struct mac_lomac *subj, *obj;
2582 
2583 	if (!mac_lomac_enabled)
2584 		return (0);
2585 
2586 	subj = SLOT(cred->cr_label);
2587 	obj = SLOT(dvplabel);
2588 
2589 	if (!mac_lomac_subject_dominate(subj, obj))
2590 		return (EACCES);
2591 
2592 	if (vp != NULL) {
2593 		obj = SLOT(vplabel);
2594 
2595 		if (!mac_lomac_subject_dominate(subj, obj))
2596 			return (EACCES);
2597 	}
2598 
2599 	return (0);
2600 }
2601 
2602 static int
2603 mac_lomac_check_vnode_revoke(struct ucred *cred, struct vnode *vp,
2604     struct label *vplabel)
2605 {
2606 	struct mac_lomac *subj, *obj;
2607 
2608 	if (!mac_lomac_enabled)
2609 		return (0);
2610 
2611 	subj = SLOT(cred->cr_label);
2612 	obj = SLOT(vplabel);
2613 
2614 	if (!mac_lomac_subject_dominate(subj, obj))
2615 		return (EACCES);
2616 
2617 	return (0);
2618 }
2619 
2620 static int
2621 mac_lomac_check_vnode_setacl(struct ucred *cred, struct vnode *vp,
2622     struct label *vplabel, acl_type_t type, struct acl *acl)
2623 {
2624 	struct mac_lomac *subj, *obj;
2625 
2626 	if (!mac_lomac_enabled)
2627 		return (0);
2628 
2629 	subj = SLOT(cred->cr_label);
2630 	obj = SLOT(vplabel);
2631 
2632 	if (!mac_lomac_subject_dominate(subj, obj))
2633 		return (EACCES);
2634 
2635 	return (0);
2636 }
2637 
2638 static int
2639 mac_lomac_check_vnode_setextattr(struct ucred *cred, struct vnode *vp,
2640     struct label *vplabel, int attrnamespace, const char *name,
2641     struct uio *uio)
2642 {
2643 	struct mac_lomac *subj, *obj;
2644 
2645 	if (!mac_lomac_enabled)
2646 		return (0);
2647 
2648 	subj = SLOT(cred->cr_label);
2649 	obj = SLOT(vplabel);
2650 
2651 	if (!mac_lomac_subject_dominate(subj, obj))
2652 		return (EACCES);
2653 
2654 	/* XXX: protect the MAC EA in a special way? */
2655 
2656 	return (0);
2657 }
2658 
2659 static int
2660 mac_lomac_check_vnode_setflags(struct ucred *cred, struct vnode *vp,
2661     struct label *vplabel, u_long flags)
2662 {
2663 	struct mac_lomac *subj, *obj;
2664 
2665 	if (!mac_lomac_enabled)
2666 		return (0);
2667 
2668 	subj = SLOT(cred->cr_label);
2669 	obj = SLOT(vplabel);
2670 
2671 	if (!mac_lomac_subject_dominate(subj, obj))
2672 		return (EACCES);
2673 
2674 	return (0);
2675 }
2676 
2677 static int
2678 mac_lomac_check_vnode_setmode(struct ucred *cred, struct vnode *vp,
2679     struct label *vplabel, mode_t mode)
2680 {
2681 	struct mac_lomac *subj, *obj;
2682 
2683 	if (!mac_lomac_enabled)
2684 		return (0);
2685 
2686 	subj = SLOT(cred->cr_label);
2687 	obj = SLOT(vplabel);
2688 
2689 	if (!mac_lomac_subject_dominate(subj, obj))
2690 		return (EACCES);
2691 
2692 	return (0);
2693 }
2694 
2695 static int
2696 mac_lomac_check_vnode_setowner(struct ucred *cred, struct vnode *vp,
2697     struct label *vplabel, uid_t uid, gid_t gid)
2698 {
2699 	struct mac_lomac *subj, *obj;
2700 
2701 	if (!mac_lomac_enabled)
2702 		return (0);
2703 
2704 	subj = SLOT(cred->cr_label);
2705 	obj = SLOT(vplabel);
2706 
2707 	if (!mac_lomac_subject_dominate(subj, obj))
2708 		return (EACCES);
2709 
2710 	return (0);
2711 }
2712 
2713 static int
2714 mac_lomac_check_vnode_setutimes(struct ucred *cred, struct vnode *vp,
2715     struct label *vplabel, struct timespec atime, struct timespec mtime)
2716 {
2717 	struct mac_lomac *subj, *obj;
2718 
2719 	if (!mac_lomac_enabled)
2720 		return (0);
2721 
2722 	subj = SLOT(cred->cr_label);
2723 	obj = SLOT(vplabel);
2724 
2725 	if (!mac_lomac_subject_dominate(subj, obj))
2726 		return (EACCES);
2727 
2728 	return (0);
2729 }
2730 
2731 static int
2732 mac_lomac_check_vnode_unlink(struct ucred *cred, struct vnode *dvp,
2733     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2734     struct componentname *cnp)
2735 {
2736 	struct mac_lomac *subj, *obj;
2737 
2738 	if (!mac_lomac_enabled)
2739 		return (0);
2740 
2741 	subj = SLOT(cred->cr_label);
2742 	obj = SLOT(dvplabel);
2743 
2744 	if (!mac_lomac_subject_dominate(subj, obj))
2745 		return (EACCES);
2746 
2747 	obj = SLOT(vplabel);
2748 
2749 	if (!mac_lomac_subject_dominate(subj, obj))
2750 		return (EACCES);
2751 
2752 	return (0);
2753 }
2754 
2755 static int
2756 mac_lomac_check_vnode_write(struct ucred *active_cred,
2757     struct ucred *file_cred, struct vnode *vp, struct label *vplabel)
2758 {
2759 	struct mac_lomac *subj, *obj;
2760 
2761 	if (!mac_lomac_enabled || !revocation_enabled)
2762 		return (0);
2763 
2764 	subj = SLOT(active_cred->cr_label);
2765 	obj = SLOT(vplabel);
2766 
2767 	if (!mac_lomac_subject_dominate(subj, obj))
2768 		return (EACCES);
2769 
2770 	return (0);
2771 }
2772 
2773 static void
2774 mac_lomac_thread_userret(struct thread *td)
2775 {
2776 	struct proc *p = td->td_proc;
2777 	struct mac_lomac_proc *subj = PSLOT(p->p_label);
2778 	struct ucred *newcred, *oldcred;
2779 	int dodrop;
2780 
2781 	mtx_lock(&subj->mtx);
2782 	if (subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) {
2783 		dodrop = 0;
2784 		mtx_unlock(&subj->mtx);
2785 		newcred = crget();
2786 		/*
2787 		 * Prevent a lock order reversal in
2788 		 * mac_cred_mmapped_drop_perms; ideally, the other
2789 		 * user of subj->mtx wouldn't be holding Giant.
2790 		 */
2791 		mtx_lock(&Giant);
2792 		PROC_LOCK(p);
2793 		mtx_lock(&subj->mtx);
2794 		/*
2795 		 * Check if we lost the race while allocating the cred.
2796 		 */
2797 		if ((subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) == 0) {
2798 			crfree(newcred);
2799 			goto out;
2800 		}
2801 		oldcred = p->p_ucred;
2802 		crcopy(newcred, oldcred);
2803 		crhold(newcred);
2804 		mac_lomac_copy(&subj->mac_lomac, SLOT(newcred->cr_label));
2805 		p->p_ucred = newcred;
2806 		crfree(oldcred);
2807 		dodrop = 1;
2808 	out:
2809 		mtx_unlock(&subj->mtx);
2810 		PROC_UNLOCK(p);
2811 		if (dodrop)
2812 			mac_cred_mmapped_drop_perms(curthread, newcred);
2813 		mtx_unlock(&Giant);
2814 	} else {
2815 		mtx_unlock(&subj->mtx);
2816 	}
2817 }
2818 
2819 static struct mac_policy_ops mac_lomac_ops =
2820 {
2821 	.mpo_init = mac_lomac_init,
2822 	.mpo_init_bpfdesc_label = mac_lomac_init_label,
2823 	.mpo_init_cred_label = mac_lomac_init_label,
2824 	.mpo_init_devfs_label = mac_lomac_init_label,
2825 	.mpo_init_ifnet_label = mac_lomac_init_label,
2826 	.mpo_init_syncache_label = mac_lomac_init_label_waitcheck,
2827 	.mpo_init_inpcb_label = mac_lomac_init_label_waitcheck,
2828 	.mpo_init_ipq_label = mac_lomac_init_label_waitcheck,
2829 	.mpo_init_mbuf_label = mac_lomac_init_label_waitcheck,
2830 	.mpo_init_mount_label = mac_lomac_init_label,
2831 	.mpo_init_pipe_label = mac_lomac_init_label,
2832 	.mpo_init_proc_label = mac_lomac_init_proc_label,
2833 	.mpo_init_socket_label = mac_lomac_init_label_waitcheck,
2834 	.mpo_init_socket_peer_label = mac_lomac_init_label_waitcheck,
2835 	.mpo_init_vnode_label = mac_lomac_init_label,
2836 	.mpo_init_syncache_from_inpcb = mac_lomac_init_syncache_from_inpcb,
2837 	.mpo_destroy_bpfdesc_label = mac_lomac_destroy_label,
2838 	.mpo_destroy_cred_label = mac_lomac_destroy_label,
2839 	.mpo_destroy_devfs_label = mac_lomac_destroy_label,
2840 	.mpo_destroy_ifnet_label = mac_lomac_destroy_label,
2841 	.mpo_destroy_inpcb_label = mac_lomac_destroy_label,
2842 	.mpo_destroy_ipq_label = mac_lomac_destroy_label,
2843 	.mpo_destroy_mbuf_label = mac_lomac_destroy_label,
2844 	.mpo_destroy_mount_label = mac_lomac_destroy_label,
2845 	.mpo_destroy_pipe_label = mac_lomac_destroy_label,
2846 	.mpo_destroy_proc_label = mac_lomac_destroy_proc_label,
2847 	.mpo_destroy_syncache_label = mac_lomac_destroy_label,
2848 	.mpo_destroy_socket_label = mac_lomac_destroy_label,
2849 	.mpo_destroy_socket_peer_label = mac_lomac_destroy_label,
2850 	.mpo_destroy_vnode_label = mac_lomac_destroy_label,
2851 	.mpo_copy_cred_label = mac_lomac_copy_label,
2852 	.mpo_copy_ifnet_label = mac_lomac_copy_label,
2853 	.mpo_copy_mbuf_label = mac_lomac_copy_label,
2854 	.mpo_copy_pipe_label = mac_lomac_copy_label,
2855 	.mpo_copy_socket_label = mac_lomac_copy_label,
2856 	.mpo_copy_vnode_label = mac_lomac_copy_label,
2857 	.mpo_externalize_cred_label = mac_lomac_externalize_label,
2858 	.mpo_externalize_ifnet_label = mac_lomac_externalize_label,
2859 	.mpo_externalize_pipe_label = mac_lomac_externalize_label,
2860 	.mpo_externalize_socket_label = mac_lomac_externalize_label,
2861 	.mpo_externalize_socket_peer_label = mac_lomac_externalize_label,
2862 	.mpo_externalize_vnode_label = mac_lomac_externalize_label,
2863 	.mpo_internalize_cred_label = mac_lomac_internalize_label,
2864 	.mpo_internalize_ifnet_label = mac_lomac_internalize_label,
2865 	.mpo_internalize_pipe_label = mac_lomac_internalize_label,
2866 	.mpo_internalize_socket_label = mac_lomac_internalize_label,
2867 	.mpo_internalize_vnode_label = mac_lomac_internalize_label,
2868 	.mpo_create_devfs_device = mac_lomac_create_devfs_device,
2869 	.mpo_create_devfs_directory = mac_lomac_create_devfs_directory,
2870 	.mpo_create_devfs_symlink = mac_lomac_create_devfs_symlink,
2871 	.mpo_create_mount = mac_lomac_create_mount,
2872 	.mpo_relabel_vnode = mac_lomac_relabel_vnode,
2873 	.mpo_update_devfs = mac_lomac_update_devfs,
2874 	.mpo_associate_vnode_devfs = mac_lomac_associate_vnode_devfs,
2875 	.mpo_associate_vnode_extattr = mac_lomac_associate_vnode_extattr,
2876 	.mpo_associate_vnode_singlelabel =
2877 	    mac_lomac_associate_vnode_singlelabel,
2878 	.mpo_create_vnode_extattr = mac_lomac_create_vnode_extattr,
2879 	.mpo_setlabel_vnode_extattr = mac_lomac_setlabel_vnode_extattr,
2880 	.mpo_create_mbuf_from_socket = mac_lomac_create_mbuf_from_socket,
2881 	.mpo_create_mbuf_from_syncache = mac_lomac_create_mbuf_from_syncache,
2882 	.mpo_create_pipe = mac_lomac_create_pipe,
2883 	.mpo_create_socket = mac_lomac_create_socket,
2884 	.mpo_create_socket_from_socket = mac_lomac_create_socket_from_socket,
2885 	.mpo_relabel_pipe = mac_lomac_relabel_pipe,
2886 	.mpo_relabel_socket = mac_lomac_relabel_socket,
2887 	.mpo_set_socket_peer_from_mbuf = mac_lomac_set_socket_peer_from_mbuf,
2888 	.mpo_set_socket_peer_from_socket =
2889 	    mac_lomac_set_socket_peer_from_socket,
2890 	.mpo_create_bpfdesc = mac_lomac_create_bpfdesc,
2891 	.mpo_create_datagram_from_ipq = mac_lomac_create_datagram_from_ipq,
2892 	.mpo_create_fragment = mac_lomac_create_fragment,
2893 	.mpo_create_ifnet = mac_lomac_create_ifnet,
2894 	.mpo_create_inpcb_from_socket = mac_lomac_create_inpcb_from_socket,
2895 	.mpo_create_ipq = mac_lomac_create_ipq,
2896 	.mpo_create_mbuf_from_inpcb = mac_lomac_create_mbuf_from_inpcb,
2897 	.mpo_create_mbuf_linklayer = mac_lomac_create_mbuf_linklayer,
2898 	.mpo_create_mbuf_from_bpfdesc = mac_lomac_create_mbuf_from_bpfdesc,
2899 	.mpo_create_mbuf_from_ifnet = mac_lomac_create_mbuf_from_ifnet,
2900 	.mpo_create_mbuf_multicast_encap =
2901 	    mac_lomac_create_mbuf_multicast_encap,
2902 	.mpo_create_mbuf_netlayer = mac_lomac_create_mbuf_netlayer,
2903 	.mpo_fragment_match = mac_lomac_fragment_match,
2904 	.mpo_relabel_ifnet = mac_lomac_relabel_ifnet,
2905 	.mpo_update_ipq = mac_lomac_update_ipq,
2906 	.mpo_inpcb_sosetlabel = mac_lomac_inpcb_sosetlabel,
2907 	.mpo_execve_transition = mac_lomac_execve_transition,
2908 	.mpo_execve_will_transition = mac_lomac_execve_will_transition,
2909 	.mpo_create_proc0 = mac_lomac_create_proc0,
2910 	.mpo_create_proc1 = mac_lomac_create_proc1,
2911 	.mpo_relabel_cred = mac_lomac_relabel_cred,
2912 	.mpo_check_bpfdesc_receive = mac_lomac_check_bpfdesc_receive,
2913 	.mpo_check_cred_relabel = mac_lomac_check_cred_relabel,
2914 	.mpo_check_cred_visible = mac_lomac_check_cred_visible,
2915 	.mpo_check_ifnet_relabel = mac_lomac_check_ifnet_relabel,
2916 	.mpo_check_ifnet_transmit = mac_lomac_check_ifnet_transmit,
2917 	.mpo_check_inpcb_deliver = mac_lomac_check_inpcb_deliver,
2918 	.mpo_check_kld_load = mac_lomac_check_kld_load,
2919 	.mpo_check_pipe_ioctl = mac_lomac_check_pipe_ioctl,
2920 	.mpo_check_pipe_read = mac_lomac_check_pipe_read,
2921 	.mpo_check_pipe_relabel = mac_lomac_check_pipe_relabel,
2922 	.mpo_check_pipe_write = mac_lomac_check_pipe_write,
2923 	.mpo_check_proc_debug = mac_lomac_check_proc_debug,
2924 	.mpo_check_proc_sched = mac_lomac_check_proc_sched,
2925 	.mpo_check_proc_signal = mac_lomac_check_proc_signal,
2926 	.mpo_check_socket_deliver = mac_lomac_check_socket_deliver,
2927 	.mpo_check_socket_relabel = mac_lomac_check_socket_relabel,
2928 	.mpo_check_socket_visible = mac_lomac_check_socket_visible,
2929 	.mpo_check_system_acct = mac_lomac_check_system_acct,
2930 	.mpo_check_system_auditctl = mac_lomac_check_system_auditctl,
2931 	.mpo_check_system_swapoff = mac_lomac_check_system_swapoff,
2932 	.mpo_check_system_swapon = mac_lomac_check_system_swapon,
2933 	.mpo_check_system_sysctl = mac_lomac_check_system_sysctl,
2934 	.mpo_check_vnode_access = mac_lomac_check_vnode_open,
2935 	.mpo_check_vnode_create = mac_lomac_check_vnode_create,
2936 	.mpo_check_vnode_deleteacl = mac_lomac_check_vnode_deleteacl,
2937 	.mpo_check_vnode_link = mac_lomac_check_vnode_link,
2938 	.mpo_check_vnode_mmap = mac_lomac_check_vnode_mmap,
2939 	.mpo_check_vnode_mmap_downgrade = mac_lomac_check_vnode_mmap_downgrade,
2940 	.mpo_check_vnode_open = mac_lomac_check_vnode_open,
2941 	.mpo_check_vnode_read = mac_lomac_check_vnode_read,
2942 	.mpo_check_vnode_relabel = mac_lomac_check_vnode_relabel,
2943 	.mpo_check_vnode_rename_from = mac_lomac_check_vnode_rename_from,
2944 	.mpo_check_vnode_rename_to = mac_lomac_check_vnode_rename_to,
2945 	.mpo_check_vnode_revoke = mac_lomac_check_vnode_revoke,
2946 	.mpo_check_vnode_setacl = mac_lomac_check_vnode_setacl,
2947 	.mpo_check_vnode_setextattr = mac_lomac_check_vnode_setextattr,
2948 	.mpo_check_vnode_setflags = mac_lomac_check_vnode_setflags,
2949 	.mpo_check_vnode_setmode = mac_lomac_check_vnode_setmode,
2950 	.mpo_check_vnode_setowner = mac_lomac_check_vnode_setowner,
2951 	.mpo_check_vnode_setutimes = mac_lomac_check_vnode_setutimes,
2952 	.mpo_check_vnode_unlink = mac_lomac_check_vnode_unlink,
2953 	.mpo_check_vnode_write = mac_lomac_check_vnode_write,
2954 	.mpo_thread_userret = mac_lomac_thread_userret,
2955 	.mpo_create_mbuf_from_firewall = mac_lomac_create_mbuf_from_firewall,
2956 	.mpo_priv_check = mac_lomac_priv_check,
2957 };
2958 
2959 MAC_POLICY_SET(&mac_lomac_ops, mac_lomac, "TrustedBSD MAC/LOMAC",
2960     MPC_LOADTIME_FLAG_NOTLATE | MPC_LOADTIME_FLAG_LABELMBUFS,
2961     &mac_lomac_slot);
2962