xref: /freebsd/sys/security/mac_lomac/mac_lomac.c (revision 81ad626541db97eb356e2c1d4a20eb2a26a766ab)
1 /*-
2  * Copyright (c) 1999-2002, 2007-2009 Robert N. M. Watson
3  * Copyright (c) 2001-2005 Networks Associates Technology, Inc.
4  * Copyright (c) 2006 SPARTA, Inc.
5  * All rights reserved.
6  *
7  * This software was developed by Robert Watson for the TrustedBSD Project.
8  *
9  * This software was developed for the FreeBSD Project in part by NAI Labs,
10  * the Security Research Division of Network Associates, Inc. under
11  * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
12  * CHATS research program.
13  *
14  * This software was enhanced by SPARTA ISSO under SPAWAR contract
15  * N66001-04-C-6019 ("SEFOS").
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  * $FreeBSD$
39  */
40 
41 /*
42  * Developed by the TrustedBSD Project.
43  *
44  * Low-watermark floating label mandatory integrity policy.
45  */
46 
47 #include <sys/types.h>
48 #include <sys/param.h>
49 #include <sys/acl.h>
50 #include <sys/conf.h>
51 #include <sys/extattr.h>
52 #include <sys/kernel.h>
53 #include <sys/malloc.h>
54 #include <sys/mman.h>
55 #include <sys/mount.h>
56 #include <sys/priv.h>
57 #include <sys/proc.h>
58 #include <sys/sbuf.h>
59 #include <sys/systm.h>
60 #include <sys/sysproto.h>
61 #include <sys/sysent.h>
62 #include <sys/systm.h>
63 #include <sys/vnode.h>
64 #include <sys/file.h>
65 #include <sys/socket.h>
66 #include <sys/socketvar.h>
67 #include <sys/sx.h>
68 #include <sys/pipe.h>
69 #include <sys/sysctl.h>
70 #include <sys/syslog.h>
71 
72 #include <fs/devfs/devfs.h>
73 
74 #include <net/bpfdesc.h>
75 #include <net/if.h>
76 #include <net/if_types.h>
77 #include <net/if_var.h>
78 
79 #include <netinet/in.h>
80 #include <netinet/in_pcb.h>
81 #include <netinet/ip_var.h>
82 
83 #include <vm/vm.h>
84 
85 #include <security/mac/mac_policy.h>
86 #include <security/mac/mac_framework.h>
87 #include <security/mac_lomac/mac_lomac.h>
88 
89 struct mac_lomac_proc {
90 	struct mac_lomac mac_lomac;
91 	struct mtx mtx;
92 };
93 
94 SYSCTL_DECL(_security_mac);
95 
96 static SYSCTL_NODE(_security_mac, OID_AUTO, lomac,
97     CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
98     "TrustedBSD mac_lomac policy controls");
99 
100 static int	lomac_label_size = sizeof(struct mac_lomac);
101 SYSCTL_INT(_security_mac_lomac, OID_AUTO, label_size, CTLFLAG_RD,
102     &lomac_label_size, 0, "Size of struct mac_lomac");
103 
104 static int	lomac_enabled = 1;
105 SYSCTL_INT(_security_mac_lomac, OID_AUTO, enabled, CTLFLAG_RWTUN,
106     &lomac_enabled, 0, "Enforce MAC/LOMAC policy");
107 
108 static int	destroyed_not_inited;
109 SYSCTL_INT(_security_mac_lomac, OID_AUTO, destroyed_not_inited, CTLFLAG_RD,
110     &destroyed_not_inited, 0, "Count of labels destroyed but not inited");
111 
112 static int	trust_all_interfaces = 0;
113 SYSCTL_INT(_security_mac_lomac, OID_AUTO, trust_all_interfaces, CTLFLAG_RDTUN,
114     &trust_all_interfaces, 0, "Consider all interfaces 'trusted' by MAC/LOMAC");
115 
116 static char	trusted_interfaces[128];
117 SYSCTL_STRING(_security_mac_lomac, OID_AUTO, trusted_interfaces, CTLFLAG_RDTUN,
118     trusted_interfaces, 0, "Interfaces considered 'trusted' by MAC/LOMAC");
119 
120 static int	ptys_equal = 0;
121 SYSCTL_INT(_security_mac_lomac, OID_AUTO, ptys_equal, CTLFLAG_RWTUN,
122     &ptys_equal, 0, "Label pty devices as lomac/equal on create");
123 
124 static int	revocation_enabled = 1;
125 SYSCTL_INT(_security_mac_lomac, OID_AUTO, revocation_enabled, CTLFLAG_RWTUN,
126     &revocation_enabled, 0, "Revoke access to objects on relabel");
127 
128 static int	lomac_slot;
129 #define	SLOT(l)	((struct mac_lomac *)mac_label_get((l), lomac_slot))
130 #define	SLOT_SET(l, val) mac_label_set((l), lomac_slot, (uintptr_t)(val))
131 #define	PSLOT(l) ((struct mac_lomac_proc *)				\
132     mac_label_get((l), lomac_slot))
133 #define	PSLOT_SET(l, val) mac_label_set((l), lomac_slot, (uintptr_t)(val))
134 
135 static MALLOC_DEFINE(M_LOMAC, "mac_lomac_label", "MAC/LOMAC labels");
136 
137 static struct mac_lomac *
138 lomac_alloc(int flag)
139 {
140 	struct mac_lomac *ml;
141 
142 	ml = malloc(sizeof(*ml), M_LOMAC, M_ZERO | flag);
143 
144 	return (ml);
145 }
146 
147 static void
148 lomac_free(struct mac_lomac *ml)
149 {
150 
151 	if (ml != NULL)
152 		free(ml, M_LOMAC);
153 	else
154 		atomic_add_int(&destroyed_not_inited, 1);
155 }
156 
157 static int
158 lomac_atmostflags(struct mac_lomac *ml, int flags)
159 {
160 
161 	if ((ml->ml_flags & flags) != ml->ml_flags)
162 		return (EINVAL);
163 	return (0);
164 }
165 
166 static int
167 lomac_dominate_element(struct mac_lomac_element *a,
168     struct mac_lomac_element *b)
169 {
170 
171 	switch (a->mle_type) {
172 	case MAC_LOMAC_TYPE_EQUAL:
173 	case MAC_LOMAC_TYPE_HIGH:
174 		return (1);
175 
176 	case MAC_LOMAC_TYPE_LOW:
177 		switch (b->mle_type) {
178 		case MAC_LOMAC_TYPE_GRADE:
179 		case MAC_LOMAC_TYPE_HIGH:
180 			return (0);
181 
182 		case MAC_LOMAC_TYPE_EQUAL:
183 		case MAC_LOMAC_TYPE_LOW:
184 			return (1);
185 
186 		default:
187 			panic("lomac_dominate_element: b->mle_type invalid");
188 		}
189 
190 	case MAC_LOMAC_TYPE_GRADE:
191 		switch (b->mle_type) {
192 		case MAC_LOMAC_TYPE_EQUAL:
193 		case MAC_LOMAC_TYPE_LOW:
194 			return (1);
195 
196 		case MAC_LOMAC_TYPE_HIGH:
197 			return (0);
198 
199 		case MAC_LOMAC_TYPE_GRADE:
200 			return (a->mle_grade >= b->mle_grade);
201 
202 		default:
203 			panic("lomac_dominate_element: b->mle_type invalid");
204 		}
205 
206 	default:
207 		panic("lomac_dominate_element: a->mle_type invalid");
208 	}
209 }
210 
211 static int
212 lomac_range_in_range(struct mac_lomac *rangea, struct mac_lomac *rangeb)
213 {
214 
215 	return (lomac_dominate_element(&rangeb->ml_rangehigh,
216 	    &rangea->ml_rangehigh) &&
217 	    lomac_dominate_element(&rangea->ml_rangelow,
218 	    &rangeb->ml_rangelow));
219 }
220 
221 static int
222 lomac_single_in_range(struct mac_lomac *single, struct mac_lomac *range)
223 {
224 
225 	KASSERT((single->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
226 	    ("lomac_single_in_range: a not single"));
227 	KASSERT((range->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
228 	    ("lomac_single_in_range: b not range"));
229 
230 	return (lomac_dominate_element(&range->ml_rangehigh,
231 	    &single->ml_single) && lomac_dominate_element(&single->ml_single,
232 	    &range->ml_rangelow));
233 }
234 
235 static int
236 lomac_auxsingle_in_range(struct mac_lomac *single, struct mac_lomac *range)
237 {
238 
239 	KASSERT((single->ml_flags & MAC_LOMAC_FLAG_AUX) != 0,
240 	    ("lomac_single_in_range: a not auxsingle"));
241 	KASSERT((range->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
242 	    ("lomac_single_in_range: b not range"));
243 
244 	return (lomac_dominate_element(&range->ml_rangehigh,
245 	    &single->ml_auxsingle) &&
246 	    lomac_dominate_element(&single->ml_auxsingle,
247 	    &range->ml_rangelow));
248 }
249 
250 static int
251 lomac_dominate_single(struct mac_lomac *a, struct mac_lomac *b)
252 {
253 	KASSERT((a->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
254 	    ("lomac_dominate_single: a not single"));
255 	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
256 	    ("lomac_dominate_single: b not single"));
257 
258 	return (lomac_dominate_element(&a->ml_single, &b->ml_single));
259 }
260 
261 static int
262 lomac_subject_dominate(struct mac_lomac *a, struct mac_lomac *b)
263 {
264 	KASSERT((~a->ml_flags &
265 	    (MAC_LOMAC_FLAG_SINGLE | MAC_LOMAC_FLAG_RANGE)) == 0,
266 	    ("lomac_dominate_single: a not subject"));
267 	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
268 	    ("lomac_dominate_single: b not single"));
269 
270 	return (lomac_dominate_element(&a->ml_rangehigh, &b->ml_single));
271 }
272 
273 static int
274 lomac_equal_element(struct mac_lomac_element *a, struct mac_lomac_element *b)
275 {
276 
277 	if (a->mle_type == MAC_LOMAC_TYPE_EQUAL ||
278 	    b->mle_type == MAC_LOMAC_TYPE_EQUAL)
279 		return (1);
280 
281 	return (a->mle_type == b->mle_type && a->mle_grade == b->mle_grade);
282 }
283 
284 static int
285 lomac_equal_single(struct mac_lomac *a, struct mac_lomac *b)
286 {
287 
288 	KASSERT((a->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
289 	    ("lomac_equal_single: a not single"));
290 	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
291 	    ("lomac_equal_single: b not single"));
292 
293 	return (lomac_equal_element(&a->ml_single, &b->ml_single));
294 }
295 
296 static int
297 lomac_contains_equal(struct mac_lomac *ml)
298 {
299 
300 	if (ml->ml_flags & MAC_LOMAC_FLAG_SINGLE)
301 		if (ml->ml_single.mle_type == MAC_LOMAC_TYPE_EQUAL)
302 			return (1);
303 	if (ml->ml_flags & MAC_LOMAC_FLAG_AUX)
304 		if (ml->ml_auxsingle.mle_type == MAC_LOMAC_TYPE_EQUAL)
305 			return (1);
306 
307 	if (ml->ml_flags & MAC_LOMAC_FLAG_RANGE) {
308 		if (ml->ml_rangelow.mle_type == MAC_LOMAC_TYPE_EQUAL)
309 			return (1);
310 		if (ml->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_EQUAL)
311 			return (1);
312 	}
313 
314 	return (0);
315 }
316 
317 static int
318 lomac_subject_privileged(struct mac_lomac *ml)
319 {
320 
321 	KASSERT((ml->ml_flags & MAC_LOMAC_FLAGS_BOTH) ==
322 	    MAC_LOMAC_FLAGS_BOTH,
323 	    ("lomac_subject_privileged: subject doesn't have both labels"));
324 
325 	/* If the single is EQUAL, it's ok. */
326 	if (ml->ml_single.mle_type == MAC_LOMAC_TYPE_EQUAL)
327 		return (0);
328 
329 	/* If either range endpoint is EQUAL, it's ok. */
330 	if (ml->ml_rangelow.mle_type == MAC_LOMAC_TYPE_EQUAL ||
331 	    ml->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_EQUAL)
332 		return (0);
333 
334 	/* If the range is low-high, it's ok. */
335 	if (ml->ml_rangelow.mle_type == MAC_LOMAC_TYPE_LOW &&
336 	    ml->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_HIGH)
337 		return (0);
338 
339 	/* It's not ok. */
340 	return (EPERM);
341 }
342 
343 static int
344 lomac_high_single(struct mac_lomac *ml)
345 {
346 
347 	KASSERT((ml->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
348 	    ("lomac_high_single: mac_lomac not single"));
349 
350 	return (ml->ml_single.mle_type == MAC_LOMAC_TYPE_HIGH);
351 }
352 
353 static int
354 lomac_valid(struct mac_lomac *ml)
355 {
356 
357 	if (ml->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
358 		switch (ml->ml_single.mle_type) {
359 		case MAC_LOMAC_TYPE_GRADE:
360 		case MAC_LOMAC_TYPE_EQUAL:
361 		case MAC_LOMAC_TYPE_HIGH:
362 		case MAC_LOMAC_TYPE_LOW:
363 			break;
364 
365 		default:
366 			return (EINVAL);
367 		}
368 	} else {
369 		if (ml->ml_single.mle_type != MAC_LOMAC_TYPE_UNDEF)
370 			return (EINVAL);
371 	}
372 
373 	if (ml->ml_flags & MAC_LOMAC_FLAG_AUX) {
374 		switch (ml->ml_auxsingle.mle_type) {
375 		case MAC_LOMAC_TYPE_GRADE:
376 		case MAC_LOMAC_TYPE_EQUAL:
377 		case MAC_LOMAC_TYPE_HIGH:
378 		case MAC_LOMAC_TYPE_LOW:
379 			break;
380 
381 		default:
382 			return (EINVAL);
383 		}
384 	} else {
385 		if (ml->ml_auxsingle.mle_type != MAC_LOMAC_TYPE_UNDEF)
386 			return (EINVAL);
387 	}
388 
389 	if (ml->ml_flags & MAC_LOMAC_FLAG_RANGE) {
390 		switch (ml->ml_rangelow.mle_type) {
391 		case MAC_LOMAC_TYPE_GRADE:
392 		case MAC_LOMAC_TYPE_EQUAL:
393 		case MAC_LOMAC_TYPE_HIGH:
394 		case MAC_LOMAC_TYPE_LOW:
395 			break;
396 
397 		default:
398 			return (EINVAL);
399 		}
400 
401 		switch (ml->ml_rangehigh.mle_type) {
402 		case MAC_LOMAC_TYPE_GRADE:
403 		case MAC_LOMAC_TYPE_EQUAL:
404 		case MAC_LOMAC_TYPE_HIGH:
405 		case MAC_LOMAC_TYPE_LOW:
406 			break;
407 
408 		default:
409 			return (EINVAL);
410 		}
411 		if (!lomac_dominate_element(&ml->ml_rangehigh,
412 		    &ml->ml_rangelow))
413 			return (EINVAL);
414 	} else {
415 		if (ml->ml_rangelow.mle_type != MAC_LOMAC_TYPE_UNDEF ||
416 		    ml->ml_rangehigh.mle_type != MAC_LOMAC_TYPE_UNDEF)
417 			return (EINVAL);
418 	}
419 
420 	return (0);
421 }
422 
423 static void
424 lomac_set_range(struct mac_lomac *ml, u_short typelow, u_short gradelow,
425     u_short typehigh, u_short gradehigh)
426 {
427 
428 	ml->ml_rangelow.mle_type = typelow;
429 	ml->ml_rangelow.mle_grade = gradelow;
430 	ml->ml_rangehigh.mle_type = typehigh;
431 	ml->ml_rangehigh.mle_grade = gradehigh;
432 	ml->ml_flags |= MAC_LOMAC_FLAG_RANGE;
433 }
434 
435 static void
436 lomac_set_single(struct mac_lomac *ml, u_short type, u_short grade)
437 {
438 
439 	ml->ml_single.mle_type = type;
440 	ml->ml_single.mle_grade = grade;
441 	ml->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
442 }
443 
444 static void
445 lomac_copy_range(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
446 {
447 
448 	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
449 	    ("lomac_copy_range: labelfrom not range"));
450 
451 	labelto->ml_rangelow = labelfrom->ml_rangelow;
452 	labelto->ml_rangehigh = labelfrom->ml_rangehigh;
453 	labelto->ml_flags |= MAC_LOMAC_FLAG_RANGE;
454 }
455 
456 static void
457 lomac_copy_single(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
458 {
459 
460 	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
461 	    ("lomac_copy_single: labelfrom not single"));
462 
463 	labelto->ml_single = labelfrom->ml_single;
464 	labelto->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
465 }
466 
467 static void
468 lomac_copy_auxsingle(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
469 {
470 
471 	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_AUX) != 0,
472 	    ("lomac_copy_auxsingle: labelfrom not auxsingle"));
473 
474 	labelto->ml_auxsingle = labelfrom->ml_auxsingle;
475 	labelto->ml_flags |= MAC_LOMAC_FLAG_AUX;
476 }
477 
478 static void
479 lomac_copy(struct mac_lomac *source, struct mac_lomac *dest)
480 {
481 
482 	if (source->ml_flags & MAC_LOMAC_FLAG_SINGLE)
483 		lomac_copy_single(source, dest);
484 	if (source->ml_flags & MAC_LOMAC_FLAG_AUX)
485 		lomac_copy_auxsingle(source, dest);
486 	if (source->ml_flags & MAC_LOMAC_FLAG_RANGE)
487 		lomac_copy_range(source, dest);
488 }
489 
490 static int	lomac_to_string(struct sbuf *sb, struct mac_lomac *ml);
491 
492 static int
493 maybe_demote(struct mac_lomac *subjlabel, struct mac_lomac *objlabel,
494     const char *actionname, const char *objname, struct vnode *vp)
495 {
496 	struct sbuf subjlabel_sb, subjtext_sb, objlabel_sb;
497 	char *subjlabeltext, *objlabeltext, *subjtext;
498 	struct mac_lomac cached_subjlabel;
499 	struct mac_lomac_proc *subj;
500 	struct vattr va;
501 	struct proc *p;
502 	pid_t pgid;
503 
504 	subj = PSLOT(curthread->td_proc->p_label);
505 
506 	p = curthread->td_proc;
507 	mtx_lock(&subj->mtx);
508         if (subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) {
509 		/*
510 		 * Check to see if the pending demotion would be more or less
511 		 * severe than this one, and keep the more severe.  This can
512 		 * only happen for a multi-threaded application.
513 		 */
514 		if (lomac_dominate_single(objlabel, &subj->mac_lomac)) {
515 			mtx_unlock(&subj->mtx);
516 			return (0);
517 		}
518 	}
519 	bzero(&subj->mac_lomac, sizeof(subj->mac_lomac));
520 	/*
521 	 * Always demote the single label.
522 	 */
523 	lomac_copy_single(objlabel, &subj->mac_lomac);
524 	/*
525 	 * Start with the original range, then minimize each side of the
526 	 * range to the point of not dominating the object.  The high side
527 	 * will always be demoted, of course.
528 	 */
529 	lomac_copy_range(subjlabel, &subj->mac_lomac);
530 	if (!lomac_dominate_element(&objlabel->ml_single,
531 	    &subj->mac_lomac.ml_rangelow))
532 		subj->mac_lomac.ml_rangelow = objlabel->ml_single;
533 	subj->mac_lomac.ml_rangehigh = objlabel->ml_single;
534 	subj->mac_lomac.ml_flags |= MAC_LOMAC_FLAG_UPDATE;
535 	ast_sched(curthread, TDA_MAC);
536 
537 	/*
538 	 * Avoid memory allocation while holding a mutex; cache the label.
539 	 */
540 	lomac_copy_single(&subj->mac_lomac, &cached_subjlabel);
541 	mtx_unlock(&subj->mtx);
542 
543 	sbuf_new(&subjlabel_sb, NULL, 0, SBUF_AUTOEXTEND);
544 	lomac_to_string(&subjlabel_sb, subjlabel);
545 	sbuf_finish(&subjlabel_sb);
546 	subjlabeltext = sbuf_data(&subjlabel_sb);
547 
548 	sbuf_new(&subjtext_sb, NULL, 0, SBUF_AUTOEXTEND);
549 	lomac_to_string(&subjtext_sb, &subj->mac_lomac);
550 	sbuf_finish(&subjtext_sb);
551 	subjtext = sbuf_data(&subjtext_sb);
552 
553 	sbuf_new(&objlabel_sb, NULL, 0, SBUF_AUTOEXTEND);
554 	lomac_to_string(&objlabel_sb, objlabel);
555 	sbuf_finish(&objlabel_sb);
556 	objlabeltext = sbuf_data(&objlabel_sb);
557 
558 	pgid = p->p_pgrp->pg_id;		/* XXX could be stale? */
559 	if (vp != NULL && VOP_GETATTR(vp, &va, curthread->td_ucred) == 0) {
560 		log(LOG_INFO, "LOMAC: level-%s subject p%dg%du%d:%s demoted to"
561 		    " level %s after %s a level-%s %s (inode=%ju, "
562 		    "mountpount=%s)\n",
563 		    subjlabeltext, p->p_pid, pgid, curthread->td_ucred->cr_uid,
564 		    p->p_comm, subjtext, actionname, objlabeltext, objname,
565 		    (uintmax_t)va.va_fileid, vp->v_mount->mnt_stat.f_mntonname);
566 	} else {
567 		log(LOG_INFO, "LOMAC: level-%s subject p%dg%du%d:%s demoted to"
568 		    " level %s after %s a level-%s %s\n",
569 		    subjlabeltext, p->p_pid, pgid, curthread->td_ucred->cr_uid,
570 		    p->p_comm, subjtext, actionname, objlabeltext, objname);
571 	}
572 
573 	sbuf_delete(&subjlabel_sb);
574 	sbuf_delete(&subjtext_sb);
575 	sbuf_delete(&objlabel_sb);
576 
577 	return (0);
578 }
579 
580 /*
581  * Relabel "to" to "from" only if "from" is a valid label (contains at least
582  * a single), as for a relabel operation which may or may not involve a
583  * relevant label.
584  */
585 static void
586 try_relabel(struct mac_lomac *from, struct mac_lomac *to)
587 {
588 
589 	if (from->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
590 		bzero(to, sizeof(*to));
591 		lomac_copy(from, to);
592 	}
593 }
594 
595 static void
596 ast_mac(struct thread *td, int tda __unused)
597 {
598 	mac_thread_userret(td);
599 }
600 
601 /*
602  * Policy module operations.
603  */
604 static void
605 lomac_init(struct mac_policy_conf *conf __unused)
606 {
607 	ast_register(TDA_MAC, ASTR_ASTF_REQUIRED, 0, ast_mac);
608 }
609 
610 static void
611 lomac_fini(struct mac_policy_conf *conf __unused)
612 {
613 	ast_deregister(TDA_MAC);
614 }
615 
616 /*
617  * Label operations.
618  */
619 static void
620 lomac_init_label(struct label *label)
621 {
622 
623 	SLOT_SET(label, lomac_alloc(M_WAITOK));
624 }
625 
626 static int
627 lomac_init_label_waitcheck(struct label *label, int flag)
628 {
629 
630 	SLOT_SET(label, lomac_alloc(flag));
631 	if (SLOT(label) == NULL)
632 		return (ENOMEM);
633 
634 	return (0);
635 }
636 
637 static void
638 lomac_destroy_label(struct label *label)
639 {
640 
641 	lomac_free(SLOT(label));
642 	SLOT_SET(label, NULL);
643 }
644 
645 static int
646 lomac_element_to_string(struct sbuf *sb, struct mac_lomac_element *element)
647 {
648 
649 	switch (element->mle_type) {
650 	case MAC_LOMAC_TYPE_HIGH:
651 		return (sbuf_printf(sb, "high"));
652 
653 	case MAC_LOMAC_TYPE_LOW:
654 		return (sbuf_printf(sb, "low"));
655 
656 	case MAC_LOMAC_TYPE_EQUAL:
657 		return (sbuf_printf(sb, "equal"));
658 
659 	case MAC_LOMAC_TYPE_GRADE:
660 		return (sbuf_printf(sb, "%d", element->mle_grade));
661 
662 	default:
663 		panic("lomac_element_to_string: invalid type (%d)",
664 		    element->mle_type);
665 	}
666 }
667 
668 static int
669 lomac_to_string(struct sbuf *sb, struct mac_lomac *ml)
670 {
671 
672 	if (ml->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
673 		if (lomac_element_to_string(sb, &ml->ml_single) == -1)
674 			return (EINVAL);
675 	}
676 
677 	if (ml->ml_flags & MAC_LOMAC_FLAG_AUX) {
678 		if (sbuf_putc(sb, '[') == -1)
679 			return (EINVAL);
680 
681 		if (lomac_element_to_string(sb, &ml->ml_auxsingle) == -1)
682 			return (EINVAL);
683 
684 		if (sbuf_putc(sb, ']') == -1)
685 			return (EINVAL);
686 	}
687 
688 	if (ml->ml_flags & MAC_LOMAC_FLAG_RANGE) {
689 		if (sbuf_putc(sb, '(') == -1)
690 			return (EINVAL);
691 
692 		if (lomac_element_to_string(sb, &ml->ml_rangelow) == -1)
693 			return (EINVAL);
694 
695 		if (sbuf_putc(sb, '-') == -1)
696 			return (EINVAL);
697 
698 		if (lomac_element_to_string(sb, &ml->ml_rangehigh) == -1)
699 			return (EINVAL);
700 
701 		if (sbuf_putc(sb, ')') == -1)
702 			return (EINVAL);
703 	}
704 
705 	return (0);
706 }
707 
708 static int
709 lomac_externalize_label(struct label *label, char *element_name,
710     struct sbuf *sb, int *claimed)
711 {
712 	struct mac_lomac *ml;
713 
714 	if (strcmp(MAC_LOMAC_LABEL_NAME, element_name) != 0)
715 		return (0);
716 
717 	(*claimed)++;
718 
719 	ml = SLOT(label);
720 
721 	return (lomac_to_string(sb, ml));
722 }
723 
724 static int
725 lomac_parse_element(struct mac_lomac_element *element, char *string)
726 {
727 
728 	if (strcmp(string, "high") == 0 || strcmp(string, "hi") == 0) {
729 		element->mle_type = MAC_LOMAC_TYPE_HIGH;
730 		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
731 	} else if (strcmp(string, "low") == 0 || strcmp(string, "lo") == 0) {
732 		element->mle_type = MAC_LOMAC_TYPE_LOW;
733 		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
734 	} else if (strcmp(string, "equal") == 0 ||
735 	    strcmp(string, "eq") == 0) {
736 		element->mle_type = MAC_LOMAC_TYPE_EQUAL;
737 		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
738 	} else {
739 		char *p0, *p1;
740 		int d;
741 
742 		p0 = string;
743 		d = strtol(p0, &p1, 10);
744 
745 		if (d < 0 || d > 65535)
746 			return (EINVAL);
747 		element->mle_type = MAC_LOMAC_TYPE_GRADE;
748 		element->mle_grade = d;
749 
750 		if (p1 == p0 || *p1 != '\0')
751 			return (EINVAL);
752 	}
753 
754 	return (0);
755 }
756 
757 /*
758  * Note: destructively consumes the string, make a local copy before calling
759  * if that's a problem.
760  */
761 static int
762 lomac_parse(struct mac_lomac *ml, char *string)
763 {
764 	char *range, *rangeend, *rangehigh, *rangelow, *single, *auxsingle,
765 	    *auxsingleend;
766 	int error;
767 
768 	/* Do we have a range? */
769 	single = string;
770 	range = strchr(string, '(');
771 	if (range == single)
772 		single = NULL;
773 	auxsingle = strchr(string, '[');
774 	if (auxsingle == single)
775 		single = NULL;
776 	if (range != NULL && auxsingle != NULL)
777 		return (EINVAL);
778 	rangelow = rangehigh = NULL;
779 	if (range != NULL) {
780 		/* Nul terminate the end of the single string. */
781 		*range = '\0';
782 		range++;
783 		rangelow = range;
784 		rangehigh = strchr(rangelow, '-');
785 		if (rangehigh == NULL)
786 			return (EINVAL);
787 		rangehigh++;
788 		if (*rangelow == '\0' || *rangehigh == '\0')
789 			return (EINVAL);
790 		rangeend = strchr(rangehigh, ')');
791 		if (rangeend == NULL)
792 			return (EINVAL);
793 		if (*(rangeend + 1) != '\0')
794 			return (EINVAL);
795 		/* Nul terminate the ends of the ranges. */
796 		*(rangehigh - 1) = '\0';
797 		*rangeend = '\0';
798 	}
799 	KASSERT((rangelow != NULL && rangehigh != NULL) ||
800 	    (rangelow == NULL && rangehigh == NULL),
801 	    ("lomac_internalize_label: range mismatch"));
802 	if (auxsingle != NULL) {
803 		/* Nul terminate the end of the single string. */
804 		*auxsingle = '\0';
805 		auxsingle++;
806 		auxsingleend = strchr(auxsingle, ']');
807 		if (auxsingleend == NULL)
808 			return (EINVAL);
809 		if (*(auxsingleend + 1) != '\0')
810 			return (EINVAL);
811 		/* Nul terminate the end of the auxsingle. */
812 		*auxsingleend = '\0';
813 	}
814 
815 	bzero(ml, sizeof(*ml));
816 	if (single != NULL) {
817 		error = lomac_parse_element(&ml->ml_single, single);
818 		if (error)
819 			return (error);
820 		ml->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
821 	}
822 
823 	if (auxsingle != NULL) {
824 		error = lomac_parse_element(&ml->ml_auxsingle, auxsingle);
825 		if (error)
826 			return (error);
827 		ml->ml_flags |= MAC_LOMAC_FLAG_AUX;
828 	}
829 
830 	if (rangelow != NULL) {
831 		error = lomac_parse_element(&ml->ml_rangelow, rangelow);
832 		if (error)
833 			return (error);
834 		error = lomac_parse_element(&ml->ml_rangehigh, rangehigh);
835 		if (error)
836 			return (error);
837 		ml->ml_flags |= MAC_LOMAC_FLAG_RANGE;
838 	}
839 
840 	error = lomac_valid(ml);
841 	if (error)
842 		return (error);
843 
844 	return (0);
845 }
846 
847 static int
848 lomac_internalize_label(struct label *label, char *element_name,
849     char *element_data, int *claimed)
850 {
851 	struct mac_lomac *ml, ml_temp;
852 	int error;
853 
854 	if (strcmp(MAC_LOMAC_LABEL_NAME, element_name) != 0)
855 		return (0);
856 
857 	(*claimed)++;
858 
859 	error = lomac_parse(&ml_temp, element_data);
860 	if (error)
861 		return (error);
862 
863 	ml = SLOT(label);
864 	*ml = ml_temp;
865 
866 	return (0);
867 }
868 
869 static void
870 lomac_copy_label(struct label *src, struct label *dest)
871 {
872 
873 	*SLOT(dest) = *SLOT(src);
874 }
875 
876 /*
877  * Object-specific entry point implementations are sorted alphabetically by
878  * object type name and then by operation.
879  */
880 static int
881 lomac_bpfdesc_check_receive(struct bpf_d *d, struct label *dlabel,
882     struct ifnet *ifp, struct label *ifplabel)
883 {
884 	struct mac_lomac *a, *b;
885 
886 	if (!lomac_enabled)
887 		return (0);
888 
889 	a = SLOT(dlabel);
890 	b = SLOT(ifplabel);
891 
892 	if (lomac_equal_single(a, b))
893 		return (0);
894 	return (EACCES);
895 }
896 
897 static void
898 lomac_bpfdesc_create(struct ucred *cred, struct bpf_d *d,
899     struct label *dlabel)
900 {
901 	struct mac_lomac *source, *dest;
902 
903 	source = SLOT(cred->cr_label);
904 	dest = SLOT(dlabel);
905 
906 	lomac_copy_single(source, dest);
907 }
908 
909 static void
910 lomac_bpfdesc_create_mbuf(struct bpf_d *d, struct label *dlabel,
911     struct mbuf *m, struct label *mlabel)
912 {
913 	struct mac_lomac *source, *dest;
914 
915 	source = SLOT(dlabel);
916 	dest = SLOT(mlabel);
917 
918 	lomac_copy_single(source, dest);
919 }
920 
921 static int
922 lomac_cred_check_relabel(struct ucred *cred, struct label *newlabel)
923 {
924 	struct mac_lomac *subj, *new;
925 	int error;
926 
927 	subj = SLOT(cred->cr_label);
928 	new = SLOT(newlabel);
929 
930 	/*
931 	 * If there is a LOMAC label update for the credential, it may be an
932 	 * update of the single, range, or both.
933 	 */
934 	error = lomac_atmostflags(new, MAC_LOMAC_FLAGS_BOTH);
935 	if (error)
936 		return (error);
937 
938 	/*
939 	 * If the LOMAC label is to be changed, authorize as appropriate.
940 	 */
941 	if (new->ml_flags & MAC_LOMAC_FLAGS_BOTH) {
942 		/*
943 		 * Fill in the missing parts from the previous label.
944 		 */
945 		if ((new->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
946 			lomac_copy_single(subj, new);
947 		if ((new->ml_flags & MAC_LOMAC_FLAG_RANGE) == 0)
948 			lomac_copy_range(subj, new);
949 
950 		/*
951 		 * To change the LOMAC range on a credential, the new range
952 		 * label must be in the current range.
953 		 */
954 		if (!lomac_range_in_range(new, subj))
955 			return (EPERM);
956 
957 		/*
958 		 * To change the LOMAC single label on a credential, the new
959 		 * single label must be in the new range.  Implicitly from
960 		 * the previous check, the new single is in the old range.
961 		 */
962 		if (!lomac_single_in_range(new, new))
963 			return (EPERM);
964 
965 		/*
966 		 * To have EQUAL in any component of the new credential LOMAC
967 		 * label, the subject must already have EQUAL in their label.
968 		 */
969 		if (lomac_contains_equal(new)) {
970 			error = lomac_subject_privileged(subj);
971 			if (error)
972 				return (error);
973 		}
974 
975 		/*
976 		 * XXXMAC: Additional consistency tests regarding the single
977 		 * and range of the new label might be performed here.
978 		 */
979 	}
980 
981 	return (0);
982 }
983 
984 static int
985 lomac_cred_check_visible(struct ucred *cr1, struct ucred *cr2)
986 {
987 	struct mac_lomac *subj, *obj;
988 
989 	if (!lomac_enabled)
990 		return (0);
991 
992 	subj = SLOT(cr1->cr_label);
993 	obj = SLOT(cr2->cr_label);
994 
995 	/* XXX: range */
996 	if (!lomac_dominate_single(obj, subj))
997 		return (ESRCH);
998 
999 	return (0);
1000 }
1001 
1002 static void
1003 lomac_cred_create_init(struct ucred *cred)
1004 {
1005 	struct mac_lomac *dest;
1006 
1007 	dest = SLOT(cred->cr_label);
1008 
1009 	lomac_set_single(dest, MAC_LOMAC_TYPE_HIGH, 0);
1010 	lomac_set_range(dest, MAC_LOMAC_TYPE_LOW, 0, MAC_LOMAC_TYPE_HIGH, 0);
1011 }
1012 
1013 static void
1014 lomac_cred_create_swapper(struct ucred *cred)
1015 {
1016 	struct mac_lomac *dest;
1017 
1018 	dest = SLOT(cred->cr_label);
1019 
1020 	lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
1021 	lomac_set_range(dest, MAC_LOMAC_TYPE_LOW, 0, MAC_LOMAC_TYPE_HIGH, 0);
1022 }
1023 
1024 static void
1025 lomac_cred_relabel(struct ucred *cred, struct label *newlabel)
1026 {
1027 	struct mac_lomac *source, *dest;
1028 
1029 	source = SLOT(newlabel);
1030 	dest = SLOT(cred->cr_label);
1031 
1032 	try_relabel(source, dest);
1033 }
1034 
1035 static void
1036 lomac_devfs_create_device(struct ucred *cred, struct mount *mp,
1037     struct cdev *dev, struct devfs_dirent *de, struct label *delabel)
1038 {
1039 	struct mac_lomac *ml;
1040 	const char *dn;
1041 	int lomac_type;
1042 
1043 	ml = SLOT(delabel);
1044 	dn = devtoname(dev);
1045 	if (strcmp(dn, "null") == 0 ||
1046 	    strcmp(dn, "zero") == 0 ||
1047 	    strcmp(dn, "random") == 0 ||
1048 	    strncmp(dn, "fd/", strlen("fd/")) == 0 ||
1049 	    strncmp(dn, "ttyv", strlen("ttyv")) == 0)
1050 		lomac_type = MAC_LOMAC_TYPE_EQUAL;
1051 	else if (ptys_equal &&
1052 	    (strncmp(dn, "ttyp", strlen("ttyp")) == 0 ||
1053 	    strncmp(dn, "pts/", strlen("pts/")) == 0 ||
1054 	    strncmp(dn, "ptyp", strlen("ptyp")) == 0))
1055 		lomac_type = MAC_LOMAC_TYPE_EQUAL;
1056 	else
1057 		lomac_type = MAC_LOMAC_TYPE_HIGH;
1058 	lomac_set_single(ml, lomac_type, 0);
1059 }
1060 
1061 static void
1062 lomac_devfs_create_directory(struct mount *mp, char *dirname, int dirnamelen,
1063     struct devfs_dirent *de, struct label *delabel)
1064 {
1065 	struct mac_lomac *ml;
1066 
1067 	ml = SLOT(delabel);
1068 	lomac_set_single(ml, MAC_LOMAC_TYPE_HIGH, 0);
1069 }
1070 
1071 static void
1072 lomac_devfs_create_symlink(struct ucred *cred, struct mount *mp,
1073     struct devfs_dirent *dd, struct label *ddlabel, struct devfs_dirent *de,
1074     struct label *delabel)
1075 {
1076 	struct mac_lomac *source, *dest;
1077 
1078 	source = SLOT(cred->cr_label);
1079 	dest = SLOT(delabel);
1080 
1081 	lomac_copy_single(source, dest);
1082 }
1083 
1084 static void
1085 lomac_devfs_update(struct mount *mp, struct devfs_dirent *de,
1086     struct label *delabel, struct vnode *vp, struct label *vplabel)
1087 {
1088 	struct mac_lomac *source, *dest;
1089 
1090 	source = SLOT(vplabel);
1091 	dest = SLOT(delabel);
1092 
1093 	lomac_copy(source, dest);
1094 }
1095 
1096 static void
1097 lomac_devfs_vnode_associate(struct mount *mp, struct label *mplabel,
1098     struct devfs_dirent *de, struct label *delabel, struct vnode *vp,
1099     struct label *vplabel)
1100 {
1101 	struct mac_lomac *source, *dest;
1102 
1103 	source = SLOT(delabel);
1104 	dest = SLOT(vplabel);
1105 
1106 	lomac_copy_single(source, dest);
1107 }
1108 
1109 static int
1110 lomac_ifnet_check_relabel(struct ucred *cred, struct ifnet *ifp,
1111     struct label *ifplabel, struct label *newlabel)
1112 {
1113 	struct mac_lomac *subj, *new;
1114 	int error;
1115 
1116 	subj = SLOT(cred->cr_label);
1117 	new = SLOT(newlabel);
1118 
1119 	/*
1120 	 * If there is a LOMAC label update for the interface, it may be an
1121 	 * update of the single, range, or both.
1122 	 */
1123 	error = lomac_atmostflags(new, MAC_LOMAC_FLAGS_BOTH);
1124 	if (error)
1125 		return (error);
1126 
1127 	/*
1128 	 * Relabling network interfaces requires LOMAC privilege.
1129 	 */
1130 	error = lomac_subject_privileged(subj);
1131 	if (error)
1132 		return (error);
1133 
1134 	/*
1135 	 * If the LOMAC label is to be changed, authorize as appropriate.
1136 	 */
1137 	if (new->ml_flags & MAC_LOMAC_FLAGS_BOTH) {
1138 		/*
1139 		 * Fill in the missing parts from the previous label.
1140 		 */
1141 		if ((new->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
1142 			lomac_copy_single(subj, new);
1143 		if ((new->ml_flags & MAC_LOMAC_FLAG_RANGE) == 0)
1144 			lomac_copy_range(subj, new);
1145 
1146 		/*
1147 		 * Rely on the traditional superuser status for the LOMAC
1148 		 * interface relabel requirements.  XXXMAC: This will go
1149 		 * away.
1150 		 *
1151 		 * XXXRW: This is also redundant to a higher layer check.
1152 		 */
1153 		error = priv_check_cred(cred, PRIV_NET_SETIFMAC);
1154 		if (error)
1155 			return (EPERM);
1156 
1157 		/*
1158 		 * XXXMAC: Additional consistency tests regarding the single
1159 		 * and the range of the new label might be performed here.
1160 		 */
1161 	}
1162 
1163 	return (0);
1164 }
1165 
1166 static int
1167 lomac_ifnet_check_transmit(struct ifnet *ifp, struct label *ifplabel,
1168     struct mbuf *m, struct label *mlabel)
1169 {
1170 	struct mac_lomac *p, *i;
1171 
1172 	if (!lomac_enabled)
1173 		return (0);
1174 
1175 	p = SLOT(mlabel);
1176 	i = SLOT(ifplabel);
1177 
1178 	return (lomac_single_in_range(p, i) ? 0 : EACCES);
1179 }
1180 
1181 static void
1182 lomac_ifnet_create(struct ifnet *ifp, struct label *ifplabel)
1183 {
1184 	char tifname[IFNAMSIZ], *p, *q;
1185 	char tiflist[sizeof(trusted_interfaces)];
1186 	struct mac_lomac *dest;
1187 	int len, grade;
1188 
1189 	dest = SLOT(ifplabel);
1190 
1191 	if (if_gettype(ifp) == IFT_LOOP) {
1192 		grade = MAC_LOMAC_TYPE_EQUAL;
1193 		goto set;
1194 	}
1195 
1196 	if (trust_all_interfaces) {
1197 		grade = MAC_LOMAC_TYPE_HIGH;
1198 		goto set;
1199 	}
1200 
1201 	grade = MAC_LOMAC_TYPE_LOW;
1202 
1203 	if (trusted_interfaces[0] == '\0' ||
1204 	    !strvalid(trusted_interfaces, sizeof(trusted_interfaces)))
1205 		goto set;
1206 
1207 	bzero(tiflist, sizeof(tiflist));
1208 	for (p = trusted_interfaces, q = tiflist; *p != '\0'; p++, q++)
1209 		if(*p != ' ' && *p != '\t')
1210 			*q = *p;
1211 
1212 	for (p = q = tiflist;; p++) {
1213 		if (*p == ',' || *p == '\0') {
1214 			len = p - q;
1215 			if (len < IFNAMSIZ) {
1216 				bzero(tifname, sizeof(tifname));
1217 				bcopy(q, tifname, len);
1218 				if (strcmp(tifname, if_name(ifp)) == 0) {
1219 					grade = MAC_LOMAC_TYPE_HIGH;
1220 					break;
1221 				}
1222 			}
1223 			else {
1224 				*p = '\0';
1225 				printf("MAC/LOMAC warning: interface name "
1226 				    "\"%s\" is too long (must be < %d)\n",
1227 				    q, IFNAMSIZ);
1228 			}
1229 			if (*p == '\0')
1230 				break;
1231 			q = p + 1;
1232 		}
1233 	}
1234 set:
1235 	lomac_set_single(dest, grade, 0);
1236 	lomac_set_range(dest, grade, 0, grade, 0);
1237 }
1238 
1239 static void
1240 lomac_ifnet_create_mbuf(struct ifnet *ifp, struct label *ifplabel,
1241     struct mbuf *m, struct label *mlabel)
1242 {
1243 	struct mac_lomac *source, *dest;
1244 
1245 	source = SLOT(ifplabel);
1246 	dest = SLOT(mlabel);
1247 
1248 	lomac_copy_single(source, dest);
1249 }
1250 
1251 static void
1252 lomac_ifnet_relabel(struct ucred *cred, struct ifnet *ifp,
1253     struct label *ifplabel, struct label *newlabel)
1254 {
1255 	struct mac_lomac *source, *dest;
1256 
1257 	source = SLOT(newlabel);
1258 	dest = SLOT(ifplabel);
1259 
1260 	try_relabel(source, dest);
1261 }
1262 
1263 static int
1264 lomac_inpcb_check_deliver(struct inpcb *inp, struct label *inplabel,
1265     struct mbuf *m, struct label *mlabel)
1266 {
1267 	struct mac_lomac *p, *i;
1268 
1269 	if (!lomac_enabled)
1270 		return (0);
1271 
1272 	p = SLOT(mlabel);
1273 	i = SLOT(inplabel);
1274 
1275 	return (lomac_equal_single(p, i) ? 0 : EACCES);
1276 }
1277 
1278 static int
1279 lomac_inpcb_check_visible(struct ucred *cred, struct inpcb *inp,
1280     struct label *inplabel)
1281 {
1282 	struct mac_lomac *subj, *obj;
1283 
1284 	if (!lomac_enabled)
1285 		return (0);
1286 
1287 	subj = SLOT(cred->cr_label);
1288 	obj = SLOT(inplabel);
1289 
1290 	if (!lomac_dominate_single(obj, subj))
1291 		return (ENOENT);
1292 
1293 	return (0);
1294 }
1295 
1296 static void
1297 lomac_inpcb_create(struct socket *so, struct label *solabel,
1298     struct inpcb *inp, struct label *inplabel)
1299 {
1300 	struct mac_lomac *source, *dest;
1301 
1302 	source = SLOT(solabel);
1303 	dest = SLOT(inplabel);
1304 
1305 	lomac_copy_single(source, dest);
1306 }
1307 
1308 static void
1309 lomac_inpcb_create_mbuf(struct inpcb *inp, struct label *inplabel,
1310     struct mbuf *m, struct label *mlabel)
1311 {
1312 	struct mac_lomac *source, *dest;
1313 
1314 	source = SLOT(inplabel);
1315 	dest = SLOT(mlabel);
1316 
1317 	lomac_copy_single(source, dest);
1318 }
1319 
1320 static void
1321 lomac_inpcb_sosetlabel(struct socket *so, struct label *solabel,
1322     struct inpcb *inp, struct label *inplabel)
1323 {
1324 	struct mac_lomac *source, *dest;
1325 
1326 	SOCK_LOCK_ASSERT(so);
1327 
1328 	source = SLOT(solabel);
1329 	dest = SLOT(inplabel);
1330 
1331 	lomac_copy_single(source, dest);
1332 }
1333 
1334 static void
1335 lomac_ip6q_create(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
1336     struct label *q6label)
1337 {
1338 	struct mac_lomac *source, *dest;
1339 
1340 	source = SLOT(mlabel);
1341 	dest = SLOT(q6label);
1342 
1343 	lomac_copy_single(source, dest);
1344 }
1345 
1346 static int
1347 lomac_ip6q_match(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
1348     struct label *q6label)
1349 {
1350 	struct mac_lomac *a, *b;
1351 
1352 	a = SLOT(q6label);
1353 	b = SLOT(mlabel);
1354 
1355 	return (lomac_equal_single(a, b));
1356 }
1357 
1358 static void
1359 lomac_ip6q_reassemble(struct ip6q *q6, struct label *q6label, struct mbuf *m,
1360     struct label *mlabel)
1361 {
1362 	struct mac_lomac *source, *dest;
1363 
1364 	source = SLOT(q6label);
1365 	dest = SLOT(mlabel);
1366 
1367 	/* Just use the head, since we require them all to match. */
1368 	lomac_copy_single(source, dest);
1369 }
1370 
1371 static void
1372 lomac_ip6q_update(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
1373     struct label *q6label)
1374 {
1375 
1376 	/* NOOP: we only accept matching labels, so no need to update */
1377 }
1378 
1379 static void
1380 lomac_ipq_create(struct mbuf *m, struct label *mlabel, struct ipq *q,
1381     struct label *qlabel)
1382 {
1383 	struct mac_lomac *source, *dest;
1384 
1385 	source = SLOT(mlabel);
1386 	dest = SLOT(qlabel);
1387 
1388 	lomac_copy_single(source, dest);
1389 }
1390 
1391 static int
1392 lomac_ipq_match(struct mbuf *m, struct label *mlabel, struct ipq *q,
1393     struct label *qlabel)
1394 {
1395 	struct mac_lomac *a, *b;
1396 
1397 	a = SLOT(qlabel);
1398 	b = SLOT(mlabel);
1399 
1400 	return (lomac_equal_single(a, b));
1401 }
1402 
1403 static void
1404 lomac_ipq_reassemble(struct ipq *q, struct label *qlabel, struct mbuf *m,
1405     struct label *mlabel)
1406 {
1407 	struct mac_lomac *source, *dest;
1408 
1409 	source = SLOT(qlabel);
1410 	dest = SLOT(mlabel);
1411 
1412 	/* Just use the head, since we require them all to match. */
1413 	lomac_copy_single(source, dest);
1414 }
1415 
1416 static void
1417 lomac_ipq_update(struct mbuf *m, struct label *mlabel, struct ipq *q,
1418     struct label *qlabel)
1419 {
1420 
1421 	/* NOOP: we only accept matching labels, so no need to update */
1422 }
1423 
1424 static int
1425 lomac_kld_check_load(struct ucred *cred, struct vnode *vp,
1426     struct label *vplabel)
1427 {
1428 	struct mac_lomac *subj, *obj;
1429 
1430 	if (!lomac_enabled)
1431 		return (0);
1432 
1433 	subj = SLOT(cred->cr_label);
1434 	obj = SLOT(vplabel);
1435 
1436 	if (lomac_subject_privileged(subj))
1437 		return (EPERM);
1438 
1439 	if (!lomac_high_single(obj))
1440 		return (EACCES);
1441 
1442 	return (0);
1443 }
1444 
1445 static void
1446 lomac_mount_create(struct ucred *cred, struct mount *mp,
1447     struct label *mplabel)
1448 {
1449 	struct mac_lomac *source, *dest;
1450 
1451 	source = SLOT(cred->cr_label);
1452 	dest = SLOT(mplabel);
1453 	lomac_copy_single(source, dest);
1454 }
1455 
1456 static void
1457 lomac_netinet_arp_send(struct ifnet *ifp, struct label *ifplabel,
1458     struct mbuf *m, struct label *mlabel)
1459 {
1460 	struct mac_lomac *dest;
1461 
1462 	dest = SLOT(mlabel);
1463 
1464 	lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
1465 }
1466 
1467 static void
1468 lomac_netinet_firewall_reply(struct mbuf *mrecv, struct label *mrecvlabel,
1469     struct mbuf *msend, struct label *msendlabel)
1470 {
1471 	struct mac_lomac *source, *dest;
1472 
1473 	source = SLOT(mrecvlabel);
1474 	dest = SLOT(msendlabel);
1475 
1476 	lomac_copy_single(source, dest);
1477 }
1478 
1479 static void
1480 lomac_netinet_firewall_send(struct mbuf *m, struct label *mlabel)
1481 {
1482 	struct mac_lomac *dest;
1483 
1484 	dest = SLOT(mlabel);
1485 
1486 	/* XXX: where is the label for the firewall really coming from? */
1487 	lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
1488 }
1489 
1490 static void
1491 lomac_netinet_fragment(struct mbuf *m, struct label *mlabel,
1492     struct mbuf *frag, struct label *fraglabel)
1493 {
1494 	struct mac_lomac *source, *dest;
1495 
1496 	source = SLOT(mlabel);
1497 	dest = SLOT(fraglabel);
1498 
1499 	lomac_copy_single(source, dest);
1500 }
1501 
1502 static void
1503 lomac_netinet_icmp_reply(struct mbuf *mrecv, struct label *mrecvlabel,
1504     struct mbuf *msend, struct label *msendlabel)
1505 {
1506 	struct mac_lomac *source, *dest;
1507 
1508 	source = SLOT(mrecvlabel);
1509 	dest = SLOT(msendlabel);
1510 
1511 	lomac_copy_single(source, dest);
1512 }
1513 
1514 static void
1515 lomac_netinet_igmp_send(struct ifnet *ifp, struct label *ifplabel,
1516     struct mbuf *m, struct label *mlabel)
1517 {
1518 	struct mac_lomac *dest;
1519 
1520 	dest = SLOT(mlabel);
1521 
1522 	lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
1523 }
1524 
1525 static void
1526 lomac_netinet6_nd6_send(struct ifnet *ifp, struct label *ifplabel,
1527     struct mbuf *m, struct label *mlabel)
1528 {
1529 	struct mac_lomac *dest;
1530 
1531 	dest = SLOT(mlabel);
1532 
1533 	lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
1534 }
1535 
1536 static int
1537 lomac_pipe_check_ioctl(struct ucred *cred, struct pipepair *pp,
1538     struct label *pplabel, unsigned long cmd, void /* caddr_t */ *data)
1539 {
1540 
1541 	if (!lomac_enabled)
1542 		return (0);
1543 
1544 	/* XXX: This will be implemented soon... */
1545 
1546 	return (0);
1547 }
1548 
1549 static int
1550 lomac_pipe_check_read(struct ucred *cred, struct pipepair *pp,
1551     struct label *pplabel)
1552 {
1553 	struct mac_lomac *subj, *obj;
1554 
1555 	if (!lomac_enabled)
1556 		return (0);
1557 
1558 	subj = SLOT(cred->cr_label);
1559 	obj = SLOT(pplabel);
1560 
1561 	if (!lomac_dominate_single(obj, subj))
1562 		return (maybe_demote(subj, obj, "reading", "pipe", NULL));
1563 
1564 	return (0);
1565 }
1566 
1567 static int
1568 lomac_pipe_check_relabel(struct ucred *cred, struct pipepair *pp,
1569     struct label *pplabel, struct label *newlabel)
1570 {
1571 	struct mac_lomac *subj, *obj, *new;
1572 	int error;
1573 
1574 	new = SLOT(newlabel);
1575 	subj = SLOT(cred->cr_label);
1576 	obj = SLOT(pplabel);
1577 
1578 	/*
1579 	 * If there is a LOMAC label update for a pipe, it must be a single
1580 	 * update.
1581 	 */
1582 	error = lomac_atmostflags(new, MAC_LOMAC_FLAG_SINGLE);
1583 	if (error)
1584 		return (error);
1585 
1586 	/*
1587 	 * To perform a relabel of a pipe (LOMAC label or not), LOMAC must
1588 	 * authorize the relabel.
1589 	 */
1590 	if (!lomac_single_in_range(obj, subj))
1591 		return (EPERM);
1592 
1593 	/*
1594 	 * If the LOMAC label is to be changed, authorize as appropriate.
1595 	 */
1596 	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
1597 		/*
1598 		 * To change the LOMAC label on a pipe, the new pipe label
1599 		 * must be in the subject range.
1600 		 */
1601 		if (!lomac_single_in_range(new, subj))
1602 			return (EPERM);
1603 
1604 		/*
1605 		 * To change the LOMAC label on a pipe to be EQUAL, the
1606 		 * subject must have appropriate privilege.
1607 		 */
1608 		if (lomac_contains_equal(new)) {
1609 			error = lomac_subject_privileged(subj);
1610 			if (error)
1611 				return (error);
1612 		}
1613 	}
1614 
1615 	return (0);
1616 }
1617 
1618 static int
1619 lomac_pipe_check_write(struct ucred *cred, struct pipepair *pp,
1620     struct label *pplabel)
1621 {
1622 	struct mac_lomac *subj, *obj;
1623 
1624 	if (!lomac_enabled)
1625 		return (0);
1626 
1627 	subj = SLOT(cred->cr_label);
1628 	obj = SLOT(pplabel);
1629 
1630 	if (!lomac_subject_dominate(subj, obj))
1631 		return (EACCES);
1632 
1633 	return (0);
1634 }
1635 
1636 static void
1637 lomac_pipe_create(struct ucred *cred, struct pipepair *pp,
1638     struct label *pplabel)
1639 {
1640 	struct mac_lomac *source, *dest;
1641 
1642 	source = SLOT(cred->cr_label);
1643 	dest = SLOT(pplabel);
1644 
1645 	lomac_copy_single(source, dest);
1646 }
1647 
1648 static void
1649 lomac_pipe_relabel(struct ucred *cred, struct pipepair *pp,
1650     struct label *pplabel, struct label *newlabel)
1651 {
1652 	struct mac_lomac *source, *dest;
1653 
1654 	source = SLOT(newlabel);
1655 	dest = SLOT(pplabel);
1656 
1657 	try_relabel(source, dest);
1658 }
1659 
1660 /*
1661  * Some system privileges are allowed regardless of integrity grade; others
1662  * are allowed only when running with privilege with respect to the LOMAC
1663  * policy as they might otherwise allow bypassing of the integrity policy.
1664  */
1665 static int
1666 lomac_priv_check(struct ucred *cred, int priv)
1667 {
1668 	struct mac_lomac *subj;
1669 	int error;
1670 
1671 	if (!lomac_enabled)
1672 		return (0);
1673 
1674 	/*
1675 	 * Exempt only specific privileges from the LOMAC integrity policy.
1676 	 */
1677 	switch (priv) {
1678 	case PRIV_KTRACE:
1679 	case PRIV_MSGBUF:
1680 
1681 	/*
1682 	 * Allow processes to manipulate basic process audit properties, and
1683 	 * to submit audit records.
1684 	 */
1685 	case PRIV_AUDIT_GETAUDIT:
1686 	case PRIV_AUDIT_SETAUDIT:
1687 	case PRIV_AUDIT_SUBMIT:
1688 
1689 	/*
1690 	 * Allow processes to manipulate their regular UNIX credentials.
1691 	 */
1692 	case PRIV_CRED_SETUID:
1693 	case PRIV_CRED_SETEUID:
1694 	case PRIV_CRED_SETGID:
1695 	case PRIV_CRED_SETEGID:
1696 	case PRIV_CRED_SETGROUPS:
1697 	case PRIV_CRED_SETREUID:
1698 	case PRIV_CRED_SETREGID:
1699 	case PRIV_CRED_SETRESUID:
1700 	case PRIV_CRED_SETRESGID:
1701 
1702 	/*
1703 	 * Allow processes to perform system monitoring.
1704 	 */
1705 	case PRIV_SEEOTHERGIDS:
1706 	case PRIV_SEEOTHERUIDS:
1707 		break;
1708 
1709 	/*
1710 	 * Allow access to general process debugging facilities.  We
1711 	 * separately control debugging based on MAC label.
1712 	 */
1713 	case PRIV_DEBUG_DIFFCRED:
1714 	case PRIV_DEBUG_SUGID:
1715 	case PRIV_DEBUG_UNPRIV:
1716 
1717 	/*
1718 	 * Allow manipulating jails.
1719 	 */
1720 	case PRIV_JAIL_ATTACH:
1721 
1722 	/*
1723 	 * Allow privilege with respect to the Partition policy, but not the
1724 	 * Privs policy.
1725 	 */
1726 	case PRIV_MAC_PARTITION:
1727 
1728 	/*
1729 	 * Allow privilege with respect to process resource limits and login
1730 	 * context.
1731 	 */
1732 	case PRIV_PROC_LIMIT:
1733 	case PRIV_PROC_SETLOGIN:
1734 	case PRIV_PROC_SETRLIMIT:
1735 
1736 	/*
1737 	 * Allow System V and POSIX IPC privileges.
1738 	 */
1739 	case PRIV_IPC_READ:
1740 	case PRIV_IPC_WRITE:
1741 	case PRIV_IPC_ADMIN:
1742 	case PRIV_IPC_MSGSIZE:
1743 	case PRIV_MQ_ADMIN:
1744 
1745 	/*
1746 	 * Allow certain scheduler manipulations -- possibly this should be
1747 	 * controlled by more fine-grained policy, as potentially low
1748 	 * integrity processes can deny CPU to higher integrity ones.
1749 	 */
1750 	case PRIV_SCHED_DIFFCRED:
1751 	case PRIV_SCHED_SETPRIORITY:
1752 	case PRIV_SCHED_RTPRIO:
1753 	case PRIV_SCHED_SETPOLICY:
1754 	case PRIV_SCHED_SET:
1755 	case PRIV_SCHED_SETPARAM:
1756 	case PRIV_SCHED_IDPRIO:
1757 
1758 	/*
1759 	 * More IPC privileges.
1760 	 */
1761 	case PRIV_SEM_WRITE:
1762 
1763 	/*
1764 	 * Allow signaling privileges subject to integrity policy.
1765 	 */
1766 	case PRIV_SIGNAL_DIFFCRED:
1767 	case PRIV_SIGNAL_SUGID:
1768 
1769 	/*
1770 	 * Allow access to only limited sysctls from lower integrity levels;
1771 	 * piggy-back on the Jail definition.
1772 	 */
1773 	case PRIV_SYSCTL_WRITEJAIL:
1774 
1775 	/*
1776 	 * Allow TTY-based privileges, subject to general device access using
1777 	 * labels on TTY device nodes, but not console privilege.
1778 	 */
1779 	case PRIV_TTY_DRAINWAIT:
1780 	case PRIV_TTY_DTRWAIT:
1781 	case PRIV_TTY_EXCLUSIVE:
1782 	case PRIV_TTY_STI:
1783 	case PRIV_TTY_SETA:
1784 
1785 	/*
1786 	 * Grant most VFS privileges, as almost all are in practice bounded
1787 	 * by more specific checks using labels.
1788 	 */
1789 	case PRIV_VFS_READ:
1790 	case PRIV_VFS_WRITE:
1791 	case PRIV_VFS_ADMIN:
1792 	case PRIV_VFS_EXEC:
1793 	case PRIV_VFS_LOOKUP:
1794 	case PRIV_VFS_CHFLAGS_DEV:
1795 	case PRIV_VFS_CHOWN:
1796 	case PRIV_VFS_CHROOT:
1797 	case PRIV_VFS_RETAINSUGID:
1798 	case PRIV_VFS_EXCEEDQUOTA:
1799 	case PRIV_VFS_FCHROOT:
1800 	case PRIV_VFS_FHOPEN:
1801 	case PRIV_VFS_FHSTATFS:
1802 	case PRIV_VFS_GENERATION:
1803 	case PRIV_VFS_GETFH:
1804 	case PRIV_VFS_GETQUOTA:
1805 	case PRIV_VFS_LINK:
1806 	case PRIV_VFS_MOUNT:
1807 	case PRIV_VFS_MOUNT_OWNER:
1808 	case PRIV_VFS_MOUNT_PERM:
1809 	case PRIV_VFS_MOUNT_SUIDDIR:
1810 	case PRIV_VFS_MOUNT_NONUSER:
1811 	case PRIV_VFS_SETGID:
1812 	case PRIV_VFS_STICKYFILE:
1813 	case PRIV_VFS_SYSFLAGS:
1814 	case PRIV_VFS_UNMOUNT:
1815 
1816 	/*
1817 	 * Allow VM privileges; it would be nice if these were subject to
1818 	 * resource limits.
1819 	 */
1820 	case PRIV_VM_MADV_PROTECT:
1821 	case PRIV_VM_MLOCK:
1822 	case PRIV_VM_MUNLOCK:
1823 	case PRIV_VM_SWAP_NOQUOTA:
1824 	case PRIV_VM_SWAP_NORLIMIT:
1825 
1826 	/*
1827 	 * Allow some but not all network privileges.  In general, dont allow
1828 	 * reconfiguring the network stack, just normal use.
1829 	 */
1830 	case PRIV_NETINET_RESERVEDPORT:
1831 	case PRIV_NETINET_RAW:
1832 	case PRIV_NETINET_REUSEPORT:
1833 		break;
1834 
1835 	/*
1836 	 * All remaining system privileges are allow only if the process
1837 	 * holds privilege with respect to the LOMAC policy.
1838 	 */
1839 	default:
1840 		subj = SLOT(cred->cr_label);
1841 		error = lomac_subject_privileged(subj);
1842 		if (error)
1843 			return (error);
1844 	}
1845 	return (0);
1846 }
1847 
1848 static int
1849 lomac_proc_check_debug(struct ucred *cred, struct proc *p)
1850 {
1851 	struct mac_lomac *subj, *obj;
1852 
1853 	if (!lomac_enabled)
1854 		return (0);
1855 
1856 	subj = SLOT(cred->cr_label);
1857 	obj = SLOT(p->p_ucred->cr_label);
1858 
1859 	/* XXX: range checks */
1860 	if (!lomac_dominate_single(obj, subj))
1861 		return (ESRCH);
1862 	if (!lomac_subject_dominate(subj, obj))
1863 		return (EACCES);
1864 
1865 	return (0);
1866 }
1867 
1868 static int
1869 lomac_proc_check_sched(struct ucred *cred, struct proc *p)
1870 {
1871 	struct mac_lomac *subj, *obj;
1872 
1873 	if (!lomac_enabled)
1874 		return (0);
1875 
1876 	subj = SLOT(cred->cr_label);
1877 	obj = SLOT(p->p_ucred->cr_label);
1878 
1879 	/* XXX: range checks */
1880 	if (!lomac_dominate_single(obj, subj))
1881 		return (ESRCH);
1882 	if (!lomac_subject_dominate(subj, obj))
1883 		return (EACCES);
1884 
1885 	return (0);
1886 }
1887 
1888 static int
1889 lomac_proc_check_signal(struct ucred *cred, struct proc *p, int signum)
1890 {
1891 	struct mac_lomac *subj, *obj;
1892 
1893 	if (!lomac_enabled)
1894 		return (0);
1895 
1896 	subj = SLOT(cred->cr_label);
1897 	obj = SLOT(p->p_ucred->cr_label);
1898 
1899 	/* XXX: range checks */
1900 	if (!lomac_dominate_single(obj, subj))
1901 		return (ESRCH);
1902 	if (!lomac_subject_dominate(subj, obj))
1903 		return (EACCES);
1904 
1905 	return (0);
1906 }
1907 
1908 static void
1909 lomac_proc_destroy_label(struct label *label)
1910 {
1911 
1912 	mtx_destroy(&PSLOT(label)->mtx);
1913 	free(PSLOT(label), M_LOMAC);
1914 	PSLOT_SET(label, NULL);
1915 }
1916 
1917 static void
1918 lomac_proc_init_label(struct label *label)
1919 {
1920 
1921 	PSLOT_SET(label, malloc(sizeof(struct mac_lomac_proc), M_LOMAC,
1922 	    M_ZERO | M_WAITOK));
1923 	mtx_init(&PSLOT(label)->mtx, "MAC/Lomac proc lock", NULL, MTX_DEF);
1924 }
1925 
1926 static int
1927 lomac_socket_check_deliver(struct socket *so, struct label *solabel,
1928     struct mbuf *m, struct label *mlabel)
1929 {
1930 	struct mac_lomac *p, *s;
1931 	int error;
1932 
1933 	if (!lomac_enabled)
1934 		return (0);
1935 
1936 	p = SLOT(mlabel);
1937 	s = SLOT(solabel);
1938 
1939 	SOCK_LOCK(so);
1940 	error = lomac_equal_single(p, s) ? 0 : EACCES;
1941 	SOCK_UNLOCK(so);
1942 	return (error);
1943 }
1944 
1945 static int
1946 lomac_socket_check_relabel(struct ucred *cred, struct socket *so,
1947     struct label *solabel, struct label *newlabel)
1948 {
1949 	struct mac_lomac *subj, *obj, *new;
1950 	int error;
1951 
1952 	SOCK_LOCK_ASSERT(so);
1953 
1954 	new = SLOT(newlabel);
1955 	subj = SLOT(cred->cr_label);
1956 	obj = SLOT(solabel);
1957 
1958 	/*
1959 	 * If there is a LOMAC label update for the socket, it may be an
1960 	 * update of single.
1961 	 */
1962 	error = lomac_atmostflags(new, MAC_LOMAC_FLAG_SINGLE);
1963 	if (error)
1964 		return (error);
1965 
1966 	/*
1967 	 * To relabel a socket, the old socket single must be in the subject
1968 	 * range.
1969 	 */
1970 	if (!lomac_single_in_range(obj, subj))
1971 		return (EPERM);
1972 
1973 	/*
1974 	 * If the LOMAC label is to be changed, authorize as appropriate.
1975 	 */
1976 	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
1977 		/*
1978 		 * To relabel a socket, the new socket single must be in the
1979 		 * subject range.
1980 		 */
1981 		if (!lomac_single_in_range(new, subj))
1982 			return (EPERM);
1983 
1984 		/*
1985 		 * To change the LOMAC label on the socket to contain EQUAL,
1986 		 * the subject must have appropriate privilege.
1987 		 */
1988 		if (lomac_contains_equal(new)) {
1989 			error = lomac_subject_privileged(subj);
1990 			if (error)
1991 				return (error);
1992 		}
1993 	}
1994 
1995 	return (0);
1996 }
1997 
1998 static int
1999 lomac_socket_check_visible(struct ucred *cred, struct socket *so,
2000     struct label *solabel)
2001 {
2002 	struct mac_lomac *subj, *obj;
2003 
2004 	if (!lomac_enabled)
2005 		return (0);
2006 
2007 	subj = SLOT(cred->cr_label);
2008 	obj = SLOT(solabel);
2009 
2010 	SOCK_LOCK(so);
2011 	if (!lomac_dominate_single(obj, subj)) {
2012 		SOCK_UNLOCK(so);
2013 		return (ENOENT);
2014 	}
2015 	SOCK_UNLOCK(so);
2016 
2017 	return (0);
2018 }
2019 
2020 static void
2021 lomac_socket_create(struct ucred *cred, struct socket *so,
2022     struct label *solabel)
2023 {
2024 	struct mac_lomac *source, *dest;
2025 
2026 	source = SLOT(cred->cr_label);
2027 	dest = SLOT(solabel);
2028 
2029 	lomac_copy_single(source, dest);
2030 }
2031 
2032 static void
2033 lomac_socket_create_mbuf(struct socket *so, struct label *solabel,
2034     struct mbuf *m, struct label *mlabel)
2035 {
2036 	struct mac_lomac *source, *dest;
2037 
2038 	source = SLOT(solabel);
2039 	dest = SLOT(mlabel);
2040 
2041 	SOCK_LOCK(so);
2042 	lomac_copy_single(source, dest);
2043 	SOCK_UNLOCK(so);
2044 }
2045 
2046 static void
2047 lomac_socket_newconn(struct socket *oldso, struct label *oldsolabel,
2048     struct socket *newso, struct label *newsolabel)
2049 {
2050 	struct mac_lomac source, *dest;
2051 
2052 	SOCK_LOCK(oldso);
2053 	source = *SLOT(oldsolabel);
2054 	SOCK_UNLOCK(oldso);
2055 
2056 	dest = SLOT(newsolabel);
2057 
2058 	SOCK_LOCK(newso);
2059 	lomac_copy_single(&source, dest);
2060 	SOCK_UNLOCK(newso);
2061 }
2062 
2063 static void
2064 lomac_socket_relabel(struct ucred *cred, struct socket *so,
2065     struct label *solabel, struct label *newlabel)
2066 {
2067 	struct mac_lomac *source, *dest;
2068 
2069 	SOCK_LOCK_ASSERT(so);
2070 
2071 	source = SLOT(newlabel);
2072 	dest = SLOT(solabel);
2073 
2074 	try_relabel(source, dest);
2075 }
2076 
2077 static void
2078 lomac_socketpeer_set_from_mbuf(struct mbuf *m, struct label *mlabel,
2079     struct socket *so, struct label *sopeerlabel)
2080 {
2081 	struct mac_lomac *source, *dest;
2082 
2083 	source = SLOT(mlabel);
2084 	dest = SLOT(sopeerlabel);
2085 
2086 	SOCK_LOCK(so);
2087 	lomac_copy_single(source, dest);
2088 	SOCK_UNLOCK(so);
2089 }
2090 
2091 static void
2092 lomac_socketpeer_set_from_socket(struct socket *oldso,
2093     struct label *oldsolabel, struct socket *newso,
2094     struct label *newsopeerlabel)
2095 {
2096 	struct mac_lomac source, *dest;
2097 
2098 	SOCK_LOCK(oldso);
2099 	source = *SLOT(oldsolabel);
2100 	SOCK_UNLOCK(oldso);
2101 
2102 	dest = SLOT(newsopeerlabel);
2103 
2104 	SOCK_LOCK(newso);
2105 	lomac_copy_single(&source, dest);
2106 	SOCK_UNLOCK(newso);
2107 }
2108 
2109 static void
2110 lomac_syncache_create(struct label *label, struct inpcb *inp)
2111 {
2112 	struct mac_lomac *source, *dest;
2113 
2114 	source = SLOT(inp->inp_label);
2115 	dest = SLOT(label);
2116 	lomac_copy(source, dest);
2117 }
2118 
2119 static void
2120 lomac_syncache_create_mbuf(struct label *sc_label, struct mbuf *m,
2121     struct label *mlabel)
2122 {
2123 	struct mac_lomac *source, *dest;
2124 
2125 	source = SLOT(sc_label);
2126 	dest = SLOT(mlabel);
2127 	lomac_copy(source, dest);
2128 }
2129 
2130 static int
2131 lomac_system_check_acct(struct ucred *cred, struct vnode *vp,
2132     struct label *vplabel)
2133 {
2134 	struct mac_lomac *subj, *obj;
2135 
2136 	if (!lomac_enabled)
2137 		return (0);
2138 
2139 	subj = SLOT(cred->cr_label);
2140 	obj = SLOT(vplabel);
2141 
2142 	if (lomac_subject_privileged(subj))
2143 		return (EPERM);
2144 
2145 	if (!lomac_high_single(obj))
2146 		return (EACCES);
2147 
2148 	return (0);
2149 }
2150 
2151 static int
2152 lomac_system_check_auditctl(struct ucred *cred, struct vnode *vp,
2153     struct label *vplabel)
2154 {
2155 	struct mac_lomac *subj, *obj;
2156 
2157 	if (!lomac_enabled)
2158 		return (0);
2159 
2160 	subj = SLOT(cred->cr_label);
2161 	obj = SLOT(vplabel);
2162 
2163 	if (lomac_subject_privileged(subj))
2164 		return (EPERM);
2165 
2166 	if (!lomac_high_single(obj))
2167 		return (EACCES);
2168 
2169 	return (0);
2170 }
2171 
2172 static int
2173 lomac_system_check_swapoff(struct ucred *cred, struct vnode *vp,
2174     struct label *vplabel)
2175 {
2176 	struct mac_lomac *subj;
2177 
2178 	if (!lomac_enabled)
2179 		return (0);
2180 
2181 	subj = SLOT(cred->cr_label);
2182 
2183 	if (lomac_subject_privileged(subj))
2184 		return (EPERM);
2185 
2186 	return (0);
2187 }
2188 
2189 static int
2190 lomac_system_check_swapon(struct ucred *cred, struct vnode *vp,
2191     struct label *vplabel)
2192 {
2193 	struct mac_lomac *subj, *obj;
2194 
2195 	if (!lomac_enabled)
2196 		return (0);
2197 
2198 	subj = SLOT(cred->cr_label);
2199 	obj = SLOT(vplabel);
2200 
2201 	if (lomac_subject_privileged(subj))
2202 		return (EPERM);
2203 
2204 	if (!lomac_high_single(obj))
2205 		return (EACCES);
2206 
2207 	return (0);
2208 }
2209 
2210 static int
2211 lomac_system_check_sysctl(struct ucred *cred, struct sysctl_oid *oidp,
2212     void *arg1, int arg2, struct sysctl_req *req)
2213 {
2214 	struct mac_lomac *subj;
2215 
2216 	if (!lomac_enabled)
2217 		return (0);
2218 
2219 	subj = SLOT(cred->cr_label);
2220 
2221 	/*
2222 	 * Treat sysctl variables without CTLFLAG_ANYBODY flag as lomac/high,
2223 	 * but also require privilege to change them.
2224 	 */
2225 	if (req->newptr != NULL && (oidp->oid_kind & CTLFLAG_ANYBODY) == 0) {
2226 #ifdef notdef
2227 		if (!lomac_subject_dominate_high(subj))
2228 			return (EACCES);
2229 #endif
2230 
2231 		if (lomac_subject_privileged(subj))
2232 			return (EPERM);
2233 	}
2234 
2235 	return (0);
2236 }
2237 
2238 static void
2239 lomac_thread_userret(struct thread *td)
2240 {
2241 	struct proc *p = td->td_proc;
2242 	struct mac_lomac_proc *subj = PSLOT(p->p_label);
2243 	struct ucred *newcred, *oldcred;
2244 	int dodrop;
2245 
2246 	mtx_lock(&subj->mtx);
2247 	if (subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) {
2248 		dodrop = 0;
2249 		mtx_unlock(&subj->mtx);
2250 		newcred = crget();
2251 		PROC_LOCK(p);
2252 		mtx_lock(&subj->mtx);
2253 		/*
2254 		 * Check if we lost the race while allocating the cred.
2255 		 */
2256 		if ((subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) == 0) {
2257 			crfree(newcred);
2258 			goto out;
2259 		}
2260 		oldcred = p->p_ucred;
2261 		crcopy(newcred, oldcred);
2262 		crhold(newcred);
2263 		lomac_copy(&subj->mac_lomac, SLOT(newcred->cr_label));
2264 		proc_set_cred(p, newcred);
2265 		crfree(oldcred);
2266 		dodrop = 1;
2267 	out:
2268 		mtx_unlock(&subj->mtx);
2269 		PROC_UNLOCK(p);
2270 		if (dodrop)
2271 			mac_proc_vm_revoke(curthread);
2272 	} else {
2273 		mtx_unlock(&subj->mtx);
2274 	}
2275 }
2276 
2277 static int
2278 lomac_vnode_associate_extattr(struct mount *mp, struct label *mplabel,
2279     struct vnode *vp, struct label *vplabel)
2280 {
2281 	struct mac_lomac ml_temp, *source, *dest;
2282 	int buflen, error;
2283 
2284 	source = SLOT(mplabel);
2285 	dest = SLOT(vplabel);
2286 
2287 	buflen = sizeof(ml_temp);
2288 	bzero(&ml_temp, buflen);
2289 
2290 	error = vn_extattr_get(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
2291 	    MAC_LOMAC_EXTATTR_NAME, &buflen, (char *)&ml_temp, curthread);
2292 	if (error == ENOATTR || error == EOPNOTSUPP) {
2293 		/* Fall back to the mntlabel. */
2294 		lomac_copy_single(source, dest);
2295 		return (0);
2296 	} else if (error)
2297 		return (error);
2298 
2299 	if (buflen != sizeof(ml_temp)) {
2300 		if (buflen != sizeof(ml_temp) - sizeof(ml_temp.ml_auxsingle)) {
2301 			printf("lomac_vnode_associate_extattr: bad size %d\n",
2302 			    buflen);
2303 			return (EPERM);
2304 		}
2305 		bzero(&ml_temp.ml_auxsingle, sizeof(ml_temp.ml_auxsingle));
2306 		buflen = sizeof(ml_temp);
2307 		(void)vn_extattr_set(vp, IO_NODELOCKED,
2308 		    MAC_LOMAC_EXTATTR_NAMESPACE, MAC_LOMAC_EXTATTR_NAME,
2309 		    buflen, (char *)&ml_temp, curthread);
2310 	}
2311 	if (lomac_valid(&ml_temp) != 0) {
2312 		printf("lomac_vnode_associate_extattr: invalid\n");
2313 		return (EPERM);
2314 	}
2315 	if ((ml_temp.ml_flags & MAC_LOMAC_FLAGS_BOTH) !=
2316 	    MAC_LOMAC_FLAG_SINGLE) {
2317 		printf("lomac_vnode_associate_extattr: not single\n");
2318 		return (EPERM);
2319 	}
2320 
2321 	lomac_copy_single(&ml_temp, dest);
2322 	return (0);
2323 }
2324 
2325 static void
2326 lomac_vnode_associate_singlelabel(struct mount *mp, struct label *mplabel,
2327     struct vnode *vp, struct label *vplabel)
2328 {
2329 	struct mac_lomac *source, *dest;
2330 
2331 	source = SLOT(mplabel);
2332 	dest = SLOT(vplabel);
2333 
2334 	lomac_copy_single(source, dest);
2335 }
2336 
2337 static int
2338 lomac_vnode_check_create(struct ucred *cred, struct vnode *dvp,
2339     struct label *dvplabel, struct componentname *cnp, struct vattr *vap)
2340 {
2341 	struct mac_lomac *subj, *obj;
2342 
2343 	if (!lomac_enabled)
2344 		return (0);
2345 
2346 	subj = SLOT(cred->cr_label);
2347 	obj = SLOT(dvplabel);
2348 
2349 	if (!lomac_subject_dominate(subj, obj))
2350 		return (EACCES);
2351 	if (obj->ml_flags & MAC_LOMAC_FLAG_AUX &&
2352 	    !lomac_dominate_element(&subj->ml_single, &obj->ml_auxsingle))
2353 		return (EACCES);
2354 
2355 	return (0);
2356 }
2357 
2358 static int
2359 lomac_vnode_check_deleteacl(struct ucred *cred, struct vnode *vp,
2360     struct label *vplabel, acl_type_t type)
2361 {
2362 	struct mac_lomac *subj, *obj;
2363 
2364 	if (!lomac_enabled)
2365 		return (0);
2366 
2367 	subj = SLOT(cred->cr_label);
2368 	obj = SLOT(vplabel);
2369 
2370 	if (!lomac_subject_dominate(subj, obj))
2371 		return (EACCES);
2372 
2373 	return (0);
2374 }
2375 
2376 static int
2377 lomac_vnode_check_link(struct ucred *cred, struct vnode *dvp,
2378     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2379     struct componentname *cnp)
2380 {
2381 	struct mac_lomac *subj, *obj;
2382 
2383 	if (!lomac_enabled)
2384 		return (0);
2385 
2386 	subj = SLOT(cred->cr_label);
2387 	obj = SLOT(dvplabel);
2388 
2389 	if (!lomac_subject_dominate(subj, obj))
2390 		return (EACCES);
2391 
2392 	obj = SLOT(vplabel);
2393 
2394 	if (!lomac_subject_dominate(subj, obj))
2395 		return (EACCES);
2396 
2397 	return (0);
2398 }
2399 
2400 static int
2401 lomac_vnode_check_mmap(struct ucred *cred, struct vnode *vp,
2402     struct label *vplabel, int prot, int flags)
2403 {
2404 	struct mac_lomac *subj, *obj;
2405 
2406 	/*
2407 	 * Rely on the use of open()-time protections to handle
2408 	 * non-revocation cases.
2409 	 */
2410 	if (!lomac_enabled)
2411 		return (0);
2412 
2413 	subj = SLOT(cred->cr_label);
2414 	obj = SLOT(vplabel);
2415 
2416 	if (((prot & VM_PROT_WRITE) != 0) && ((flags & MAP_SHARED) != 0)) {
2417 		if (!lomac_subject_dominate(subj, obj))
2418 			return (EACCES);
2419 	}
2420 	if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
2421 		if (!lomac_dominate_single(obj, subj))
2422 			return (maybe_demote(subj, obj, "mapping", "file", vp));
2423 	}
2424 
2425 	return (0);
2426 }
2427 
2428 static void
2429 lomac_vnode_check_mmap_downgrade(struct ucred *cred, struct vnode *vp,
2430     struct label *vplabel, /* XXX vm_prot_t */ int *prot)
2431 {
2432 	struct mac_lomac *subj, *obj;
2433 
2434 	/*
2435 	 * Rely on the use of open()-time protections to handle
2436 	 * non-revocation cases.
2437 	 */
2438 	if (!lomac_enabled || !revocation_enabled)
2439 		return;
2440 
2441 	subj = SLOT(cred->cr_label);
2442 	obj = SLOT(vplabel);
2443 
2444 	if (!lomac_subject_dominate(subj, obj))
2445 		*prot &= ~VM_PROT_WRITE;
2446 }
2447 
2448 static int
2449 lomac_vnode_check_open(struct ucred *cred, struct vnode *vp,
2450     struct label *vplabel, accmode_t accmode)
2451 {
2452 	struct mac_lomac *subj, *obj;
2453 
2454 	if (!lomac_enabled)
2455 		return (0);
2456 
2457 	subj = SLOT(cred->cr_label);
2458 	obj = SLOT(vplabel);
2459 
2460 	/* XXX privilege override for admin? */
2461 	if (accmode & VMODIFY_PERMS) {
2462 		if (!lomac_subject_dominate(subj, obj))
2463 			return (EACCES);
2464 	}
2465 
2466 	return (0);
2467 }
2468 
2469 static int
2470 lomac_vnode_check_read(struct ucred *active_cred, struct ucred *file_cred,
2471     struct vnode *vp, struct label *vplabel)
2472 {
2473 	struct mac_lomac *subj, *obj;
2474 
2475 	if (!lomac_enabled || !revocation_enabled)
2476 		return (0);
2477 
2478 	subj = SLOT(active_cred->cr_label);
2479 	obj = SLOT(vplabel);
2480 
2481 	if (!lomac_dominate_single(obj, subj))
2482 		return (maybe_demote(subj, obj, "reading", "file", vp));
2483 
2484 	return (0);
2485 }
2486 
2487 static int
2488 lomac_vnode_check_relabel(struct ucred *cred, struct vnode *vp,
2489     struct label *vplabel, struct label *newlabel)
2490 {
2491 	struct mac_lomac *old, *new, *subj;
2492 	int error;
2493 
2494 	old = SLOT(vplabel);
2495 	new = SLOT(newlabel);
2496 	subj = SLOT(cred->cr_label);
2497 
2498 	/*
2499 	 * If there is a LOMAC label update for the vnode, it must be a
2500 	 * single label, with an optional explicit auxiliary single.
2501 	 */
2502 	error = lomac_atmostflags(new,
2503 	    MAC_LOMAC_FLAG_SINGLE | MAC_LOMAC_FLAG_AUX);
2504 	if (error)
2505 		return (error);
2506 
2507 	/*
2508 	 * To perform a relabel of the vnode (LOMAC label or not), LOMAC must
2509 	 * authorize the relabel.
2510 	 */
2511 	if (!lomac_single_in_range(old, subj))
2512 		return (EPERM);
2513 
2514 	/*
2515 	 * If the LOMAC label is to be changed, authorize as appropriate.
2516 	 */
2517 	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
2518 		/*
2519 		 * To change the LOMAC label on a vnode, the new vnode label
2520 		 * must be in the subject range.
2521 		 */
2522 		if (!lomac_single_in_range(new, subj))
2523 			return (EPERM);
2524 
2525 		/*
2526 		 * To change the LOMAC label on the vnode to be EQUAL, the
2527 		 * subject must have appropriate privilege.
2528 		 */
2529 		if (lomac_contains_equal(new)) {
2530 			error = lomac_subject_privileged(subj);
2531 			if (error)
2532 				return (error);
2533 		}
2534 	}
2535 	if (new->ml_flags & MAC_LOMAC_FLAG_AUX) {
2536 		/*
2537 		 * Fill in the missing parts from the previous label.
2538 		 */
2539 		if ((new->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
2540 			lomac_copy_single(subj, new);
2541 
2542 		/*
2543 		 * To change the auxiliary LOMAC label on a vnode, the new
2544 		 * vnode label must be in the subject range.
2545 		 */
2546 		if (!lomac_auxsingle_in_range(new, subj))
2547 			return (EPERM);
2548 
2549 		/*
2550 		 * To change the auxiliary LOMAC label on the vnode to be
2551 		 * EQUAL, the subject must have appropriate privilege.
2552 		 */
2553 		if (lomac_contains_equal(new)) {
2554 			error = lomac_subject_privileged(subj);
2555 			if (error)
2556 				return (error);
2557 		}
2558 	}
2559 
2560 	return (0);
2561 }
2562 
2563 static int
2564 lomac_vnode_check_rename_from(struct ucred *cred, struct vnode *dvp,
2565     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2566     struct componentname *cnp)
2567 {
2568 	struct mac_lomac *subj, *obj;
2569 
2570 	if (!lomac_enabled)
2571 		return (0);
2572 
2573 	subj = SLOT(cred->cr_label);
2574 	obj = SLOT(dvplabel);
2575 
2576 	if (!lomac_subject_dominate(subj, obj))
2577 		return (EACCES);
2578 
2579 	obj = SLOT(vplabel);
2580 
2581 	if (!lomac_subject_dominate(subj, obj))
2582 		return (EACCES);
2583 
2584 	return (0);
2585 }
2586 
2587 static int
2588 lomac_vnode_check_rename_to(struct ucred *cred, struct vnode *dvp,
2589     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2590     int samedir, struct componentname *cnp)
2591 {
2592 	struct mac_lomac *subj, *obj;
2593 
2594 	if (!lomac_enabled)
2595 		return (0);
2596 
2597 	subj = SLOT(cred->cr_label);
2598 	obj = SLOT(dvplabel);
2599 
2600 	if (!lomac_subject_dominate(subj, obj))
2601 		return (EACCES);
2602 
2603 	if (vp != NULL) {
2604 		obj = SLOT(vplabel);
2605 
2606 		if (!lomac_subject_dominate(subj, obj))
2607 			return (EACCES);
2608 	}
2609 
2610 	return (0);
2611 }
2612 
2613 static int
2614 lomac_vnode_check_revoke(struct ucred *cred, struct vnode *vp,
2615     struct label *vplabel)
2616 {
2617 	struct mac_lomac *subj, *obj;
2618 
2619 	if (!lomac_enabled)
2620 		return (0);
2621 
2622 	subj = SLOT(cred->cr_label);
2623 	obj = SLOT(vplabel);
2624 
2625 	if (!lomac_subject_dominate(subj, obj))
2626 		return (EACCES);
2627 
2628 	return (0);
2629 }
2630 
2631 static int
2632 lomac_vnode_check_setacl(struct ucred *cred, struct vnode *vp,
2633     struct label *vplabel, acl_type_t type, struct acl *acl)
2634 {
2635 	struct mac_lomac *subj, *obj;
2636 
2637 	if (!lomac_enabled)
2638 		return (0);
2639 
2640 	subj = SLOT(cred->cr_label);
2641 	obj = SLOT(vplabel);
2642 
2643 	if (!lomac_subject_dominate(subj, obj))
2644 		return (EACCES);
2645 
2646 	return (0);
2647 }
2648 
2649 static int
2650 lomac_vnode_check_setextattr(struct ucred *cred, struct vnode *vp,
2651     struct label *vplabel, int attrnamespace, const char *name)
2652 {
2653 	struct mac_lomac *subj, *obj;
2654 
2655 	if (!lomac_enabled)
2656 		return (0);
2657 
2658 	subj = SLOT(cred->cr_label);
2659 	obj = SLOT(vplabel);
2660 
2661 	if (!lomac_subject_dominate(subj, obj))
2662 		return (EACCES);
2663 
2664 	/* XXX: protect the MAC EA in a special way? */
2665 
2666 	return (0);
2667 }
2668 
2669 static int
2670 lomac_vnode_check_setflags(struct ucred *cred, struct vnode *vp,
2671     struct label *vplabel, u_long flags)
2672 {
2673 	struct mac_lomac *subj, *obj;
2674 
2675 	if (!lomac_enabled)
2676 		return (0);
2677 
2678 	subj = SLOT(cred->cr_label);
2679 	obj = SLOT(vplabel);
2680 
2681 	if (!lomac_subject_dominate(subj, obj))
2682 		return (EACCES);
2683 
2684 	return (0);
2685 }
2686 
2687 static int
2688 lomac_vnode_check_setmode(struct ucred *cred, struct vnode *vp,
2689     struct label *vplabel, mode_t mode)
2690 {
2691 	struct mac_lomac *subj, *obj;
2692 
2693 	if (!lomac_enabled)
2694 		return (0);
2695 
2696 	subj = SLOT(cred->cr_label);
2697 	obj = SLOT(vplabel);
2698 
2699 	if (!lomac_subject_dominate(subj, obj))
2700 		return (EACCES);
2701 
2702 	return (0);
2703 }
2704 
2705 static int
2706 lomac_vnode_check_setowner(struct ucred *cred, struct vnode *vp,
2707     struct label *vplabel, uid_t uid, gid_t gid)
2708 {
2709 	struct mac_lomac *subj, *obj;
2710 
2711 	if (!lomac_enabled)
2712 		return (0);
2713 
2714 	subj = SLOT(cred->cr_label);
2715 	obj = SLOT(vplabel);
2716 
2717 	if (!lomac_subject_dominate(subj, obj))
2718 		return (EACCES);
2719 
2720 	return (0);
2721 }
2722 
2723 static int
2724 lomac_vnode_check_setutimes(struct ucred *cred, struct vnode *vp,
2725     struct label *vplabel, struct timespec atime, struct timespec mtime)
2726 {
2727 	struct mac_lomac *subj, *obj;
2728 
2729 	if (!lomac_enabled)
2730 		return (0);
2731 
2732 	subj = SLOT(cred->cr_label);
2733 	obj = SLOT(vplabel);
2734 
2735 	if (!lomac_subject_dominate(subj, obj))
2736 		return (EACCES);
2737 
2738 	return (0);
2739 }
2740 
2741 static int
2742 lomac_vnode_check_unlink(struct ucred *cred, struct vnode *dvp,
2743     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2744     struct componentname *cnp)
2745 {
2746 	struct mac_lomac *subj, *obj;
2747 
2748 	if (!lomac_enabled)
2749 		return (0);
2750 
2751 	subj = SLOT(cred->cr_label);
2752 	obj = SLOT(dvplabel);
2753 
2754 	if (!lomac_subject_dominate(subj, obj))
2755 		return (EACCES);
2756 
2757 	obj = SLOT(vplabel);
2758 
2759 	if (!lomac_subject_dominate(subj, obj))
2760 		return (EACCES);
2761 
2762 	return (0);
2763 }
2764 
2765 static int
2766 lomac_vnode_check_write(struct ucred *active_cred,
2767     struct ucred *file_cred, struct vnode *vp, struct label *vplabel)
2768 {
2769 	struct mac_lomac *subj, *obj;
2770 
2771 	if (!lomac_enabled || !revocation_enabled)
2772 		return (0);
2773 
2774 	subj = SLOT(active_cred->cr_label);
2775 	obj = SLOT(vplabel);
2776 
2777 	if (!lomac_subject_dominate(subj, obj))
2778 		return (EACCES);
2779 
2780 	return (0);
2781 }
2782 
2783 static int
2784 lomac_vnode_create_extattr(struct ucred *cred, struct mount *mp,
2785     struct label *mplabel, struct vnode *dvp, struct label *dvplabel,
2786     struct vnode *vp, struct label *vplabel, struct componentname *cnp)
2787 {
2788 	struct mac_lomac *source, *dest, *dir, temp;
2789 	size_t buflen;
2790 	int error;
2791 
2792 	buflen = sizeof(temp);
2793 	bzero(&temp, buflen);
2794 
2795 	source = SLOT(cred->cr_label);
2796 	dest = SLOT(vplabel);
2797 	dir = SLOT(dvplabel);
2798 	if (dir->ml_flags & MAC_LOMAC_FLAG_AUX) {
2799 		lomac_copy_auxsingle(dir, &temp);
2800 		lomac_set_single(&temp, dir->ml_auxsingle.mle_type,
2801 		    dir->ml_auxsingle.mle_grade);
2802 	} else {
2803 		lomac_copy_single(source, &temp);
2804 	}
2805 
2806 	error = vn_extattr_set(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
2807 	    MAC_LOMAC_EXTATTR_NAME, buflen, (char *)&temp, curthread);
2808 	if (error == 0)
2809 		lomac_copy(&temp, dest);
2810 	return (error);
2811 }
2812 
2813 static void
2814 lomac_vnode_execve_transition(struct ucred *old, struct ucred *new,
2815     struct vnode *vp, struct label *vplabel, struct label *interpvplabel,
2816     struct image_params *imgp, struct label *execlabel)
2817 {
2818 	struct mac_lomac *source, *dest, *obj, *robj;
2819 
2820 	source = SLOT(old->cr_label);
2821 	dest = SLOT(new->cr_label);
2822 	obj = SLOT(vplabel);
2823 	robj = interpvplabel != NULL ? SLOT(interpvplabel) : obj;
2824 
2825 	lomac_copy(source, dest);
2826 	/*
2827 	 * If there's an auxiliary label on the real object, respect it and
2828 	 * assume that this level should be assumed immediately if a higher
2829 	 * level is currently in place.
2830 	 */
2831 	if (robj->ml_flags & MAC_LOMAC_FLAG_AUX &&
2832 	    !lomac_dominate_element(&robj->ml_auxsingle, &dest->ml_single)
2833 	    && lomac_auxsingle_in_range(robj, dest))
2834 		lomac_set_single(dest, robj->ml_auxsingle.mle_type,
2835 		    robj->ml_auxsingle.mle_grade);
2836 	/*
2837 	 * Restructuring to use the execve transitioning mechanism instead of
2838 	 * the normal demotion mechanism here would be difficult, so just
2839 	 * copy the label over and perform standard demotion.  This is also
2840 	 * non-optimal because it will result in the intermediate label "new"
2841 	 * being created and immediately recycled.
2842 	 */
2843 	if (lomac_enabled && revocation_enabled &&
2844 	    !lomac_dominate_single(obj, source))
2845 		(void)maybe_demote(source, obj, "executing", "file", vp);
2846 }
2847 
2848 static int
2849 lomac_vnode_execve_will_transition(struct ucred *old, struct vnode *vp,
2850     struct label *vplabel, struct label *interpvplabel,
2851     struct image_params *imgp, struct label *execlabel)
2852 {
2853 	struct mac_lomac *subj, *obj, *robj;
2854 
2855 	if (!lomac_enabled || !revocation_enabled)
2856 		return (0);
2857 
2858 	subj = SLOT(old->cr_label);
2859 	obj = SLOT(vplabel);
2860 	robj = interpvplabel != NULL ? SLOT(interpvplabel) : obj;
2861 
2862 	return ((robj->ml_flags & MAC_LOMAC_FLAG_AUX &&
2863 	    !lomac_dominate_element(&robj->ml_auxsingle, &subj->ml_single)
2864 	    && lomac_auxsingle_in_range(robj, subj)) ||
2865 	    !lomac_dominate_single(obj, subj));
2866 }
2867 
2868 static void
2869 lomac_vnode_relabel(struct ucred *cred, struct vnode *vp,
2870     struct label *vplabel, struct label *newlabel)
2871 {
2872 	struct mac_lomac *source, *dest;
2873 
2874 	source = SLOT(newlabel);
2875 	dest = SLOT(vplabel);
2876 
2877 	try_relabel(source, dest);
2878 }
2879 
2880 static int
2881 lomac_vnode_setlabel_extattr(struct ucred *cred, struct vnode *vp,
2882     struct label *vplabel, struct label *intlabel)
2883 {
2884 	struct mac_lomac *source, temp;
2885 	size_t buflen;
2886 	int error;
2887 
2888 	buflen = sizeof(temp);
2889 	bzero(&temp, buflen);
2890 
2891 	source = SLOT(intlabel);
2892 	if ((source->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
2893 		return (0);
2894 
2895 	lomac_copy_single(source, &temp);
2896 	error = vn_extattr_set(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
2897 	    MAC_LOMAC_EXTATTR_NAME, buflen, (char *)&temp, curthread);
2898 	return (error);
2899 }
2900 
2901 static struct mac_policy_ops lomac_ops =
2902 {
2903 	.mpo_init = lomac_init,
2904 	.mpo_destroy = lomac_fini,
2905 
2906 	.mpo_bpfdesc_check_receive = lomac_bpfdesc_check_receive,
2907 	.mpo_bpfdesc_create = lomac_bpfdesc_create,
2908 	.mpo_bpfdesc_create_mbuf = lomac_bpfdesc_create_mbuf,
2909 	.mpo_bpfdesc_destroy_label = lomac_destroy_label,
2910 	.mpo_bpfdesc_init_label = lomac_init_label,
2911 
2912 	.mpo_cred_check_relabel = lomac_cred_check_relabel,
2913 	.mpo_cred_check_visible = lomac_cred_check_visible,
2914 	.mpo_cred_copy_label = lomac_copy_label,
2915 	.mpo_cred_create_swapper = lomac_cred_create_swapper,
2916 	.mpo_cred_create_init = lomac_cred_create_init,
2917 	.mpo_cred_destroy_label = lomac_destroy_label,
2918 	.mpo_cred_externalize_label = lomac_externalize_label,
2919 	.mpo_cred_init_label = lomac_init_label,
2920 	.mpo_cred_internalize_label = lomac_internalize_label,
2921 	.mpo_cred_relabel = lomac_cred_relabel,
2922 
2923 	.mpo_devfs_create_device = lomac_devfs_create_device,
2924 	.mpo_devfs_create_directory = lomac_devfs_create_directory,
2925 	.mpo_devfs_create_symlink = lomac_devfs_create_symlink,
2926 	.mpo_devfs_destroy_label = lomac_destroy_label,
2927 	.mpo_devfs_init_label = lomac_init_label,
2928 	.mpo_devfs_update = lomac_devfs_update,
2929 	.mpo_devfs_vnode_associate = lomac_devfs_vnode_associate,
2930 
2931 	.mpo_ifnet_check_relabel = lomac_ifnet_check_relabel,
2932 	.mpo_ifnet_check_transmit = lomac_ifnet_check_transmit,
2933 	.mpo_ifnet_copy_label = lomac_copy_label,
2934 	.mpo_ifnet_create = lomac_ifnet_create,
2935 	.mpo_ifnet_create_mbuf = lomac_ifnet_create_mbuf,
2936 	.mpo_ifnet_destroy_label = lomac_destroy_label,
2937 	.mpo_ifnet_externalize_label = lomac_externalize_label,
2938 	.mpo_ifnet_init_label = lomac_init_label,
2939 	.mpo_ifnet_internalize_label = lomac_internalize_label,
2940 	.mpo_ifnet_relabel = lomac_ifnet_relabel,
2941 
2942 	.mpo_syncache_create = lomac_syncache_create,
2943 	.mpo_syncache_destroy_label = lomac_destroy_label,
2944 	.mpo_syncache_init_label = lomac_init_label_waitcheck,
2945 
2946 	.mpo_inpcb_check_deliver = lomac_inpcb_check_deliver,
2947 	.mpo_inpcb_check_visible = lomac_inpcb_check_visible,
2948 	.mpo_inpcb_create = lomac_inpcb_create,
2949 	.mpo_inpcb_create_mbuf = lomac_inpcb_create_mbuf,
2950 	.mpo_inpcb_destroy_label = lomac_destroy_label,
2951 	.mpo_inpcb_init_label = lomac_init_label_waitcheck,
2952 	.mpo_inpcb_sosetlabel = lomac_inpcb_sosetlabel,
2953 
2954 	.mpo_ip6q_create = lomac_ip6q_create,
2955 	.mpo_ip6q_destroy_label = lomac_destroy_label,
2956 	.mpo_ip6q_init_label = lomac_init_label_waitcheck,
2957 	.mpo_ip6q_match = lomac_ip6q_match,
2958 	.mpo_ip6q_reassemble = lomac_ip6q_reassemble,
2959 	.mpo_ip6q_update = lomac_ip6q_update,
2960 
2961 	.mpo_ipq_create = lomac_ipq_create,
2962 	.mpo_ipq_destroy_label = lomac_destroy_label,
2963 	.mpo_ipq_init_label = lomac_init_label_waitcheck,
2964 	.mpo_ipq_match = lomac_ipq_match,
2965 	.mpo_ipq_reassemble = lomac_ipq_reassemble,
2966 	.mpo_ipq_update = lomac_ipq_update,
2967 
2968 	.mpo_kld_check_load = lomac_kld_check_load,
2969 
2970 	.mpo_mbuf_copy_label = lomac_copy_label,
2971 	.mpo_mbuf_destroy_label = lomac_destroy_label,
2972 	.mpo_mbuf_init_label = lomac_init_label_waitcheck,
2973 
2974 	.mpo_mount_create = lomac_mount_create,
2975 	.mpo_mount_destroy_label = lomac_destroy_label,
2976 	.mpo_mount_init_label = lomac_init_label,
2977 
2978 	.mpo_netinet_arp_send = lomac_netinet_arp_send,
2979 	.mpo_netinet_firewall_reply = lomac_netinet_firewall_reply,
2980 	.mpo_netinet_firewall_send = lomac_netinet_firewall_send,
2981 	.mpo_netinet_fragment = lomac_netinet_fragment,
2982 	.mpo_netinet_icmp_reply = lomac_netinet_icmp_reply,
2983 	.mpo_netinet_igmp_send = lomac_netinet_igmp_send,
2984 
2985 	.mpo_netinet6_nd6_send = lomac_netinet6_nd6_send,
2986 
2987 	.mpo_pipe_check_ioctl = lomac_pipe_check_ioctl,
2988 	.mpo_pipe_check_read = lomac_pipe_check_read,
2989 	.mpo_pipe_check_relabel = lomac_pipe_check_relabel,
2990 	.mpo_pipe_check_write = lomac_pipe_check_write,
2991 	.mpo_pipe_copy_label = lomac_copy_label,
2992 	.mpo_pipe_create = lomac_pipe_create,
2993 	.mpo_pipe_destroy_label = lomac_destroy_label,
2994 	.mpo_pipe_externalize_label = lomac_externalize_label,
2995 	.mpo_pipe_init_label = lomac_init_label,
2996 	.mpo_pipe_internalize_label = lomac_internalize_label,
2997 	.mpo_pipe_relabel = lomac_pipe_relabel,
2998 
2999 	.mpo_priv_check = lomac_priv_check,
3000 
3001 	.mpo_proc_check_debug = lomac_proc_check_debug,
3002 	.mpo_proc_check_sched = lomac_proc_check_sched,
3003 	.mpo_proc_check_signal = lomac_proc_check_signal,
3004 	.mpo_proc_destroy_label = lomac_proc_destroy_label,
3005 	.mpo_proc_init_label = lomac_proc_init_label,
3006 
3007 	.mpo_socket_check_deliver = lomac_socket_check_deliver,
3008 	.mpo_socket_check_relabel = lomac_socket_check_relabel,
3009 	.mpo_socket_check_visible = lomac_socket_check_visible,
3010 	.mpo_socket_copy_label = lomac_copy_label,
3011 	.mpo_socket_create = lomac_socket_create,
3012 	.mpo_socket_create_mbuf = lomac_socket_create_mbuf,
3013 	.mpo_socket_destroy_label = lomac_destroy_label,
3014 	.mpo_socket_externalize_label = lomac_externalize_label,
3015 	.mpo_socket_init_label = lomac_init_label_waitcheck,
3016 	.mpo_socket_internalize_label = lomac_internalize_label,
3017 	.mpo_socket_newconn = lomac_socket_newconn,
3018 	.mpo_socket_relabel = lomac_socket_relabel,
3019 
3020 	.mpo_socketpeer_destroy_label = lomac_destroy_label,
3021 	.mpo_socketpeer_externalize_label = lomac_externalize_label,
3022 	.mpo_socketpeer_init_label = lomac_init_label_waitcheck,
3023 	.mpo_socketpeer_set_from_mbuf = lomac_socketpeer_set_from_mbuf,
3024 	.mpo_socketpeer_set_from_socket = lomac_socketpeer_set_from_socket,
3025 
3026 	.mpo_syncache_create_mbuf = lomac_syncache_create_mbuf,
3027 
3028 	.mpo_system_check_acct = lomac_system_check_acct,
3029 	.mpo_system_check_auditctl = lomac_system_check_auditctl,
3030 	.mpo_system_check_swapoff = lomac_system_check_swapoff,
3031 	.mpo_system_check_swapon = lomac_system_check_swapon,
3032 	.mpo_system_check_sysctl = lomac_system_check_sysctl,
3033 
3034 	.mpo_thread_userret = lomac_thread_userret,
3035 
3036 	.mpo_vnode_associate_extattr = lomac_vnode_associate_extattr,
3037 	.mpo_vnode_associate_singlelabel = lomac_vnode_associate_singlelabel,
3038 	.mpo_vnode_check_access = lomac_vnode_check_open,
3039 	.mpo_vnode_check_create = lomac_vnode_check_create,
3040 	.mpo_vnode_check_deleteacl = lomac_vnode_check_deleteacl,
3041 	.mpo_vnode_check_link = lomac_vnode_check_link,
3042 	.mpo_vnode_check_mmap = lomac_vnode_check_mmap,
3043 	.mpo_vnode_check_mmap_downgrade = lomac_vnode_check_mmap_downgrade,
3044 	.mpo_vnode_check_open = lomac_vnode_check_open,
3045 	.mpo_vnode_check_read = lomac_vnode_check_read,
3046 	.mpo_vnode_check_relabel = lomac_vnode_check_relabel,
3047 	.mpo_vnode_check_rename_from = lomac_vnode_check_rename_from,
3048 	.mpo_vnode_check_rename_to = lomac_vnode_check_rename_to,
3049 	.mpo_vnode_check_revoke = lomac_vnode_check_revoke,
3050 	.mpo_vnode_check_setacl = lomac_vnode_check_setacl,
3051 	.mpo_vnode_check_setextattr = lomac_vnode_check_setextattr,
3052 	.mpo_vnode_check_setflags = lomac_vnode_check_setflags,
3053 	.mpo_vnode_check_setmode = lomac_vnode_check_setmode,
3054 	.mpo_vnode_check_setowner = lomac_vnode_check_setowner,
3055 	.mpo_vnode_check_setutimes = lomac_vnode_check_setutimes,
3056 	.mpo_vnode_check_unlink = lomac_vnode_check_unlink,
3057 	.mpo_vnode_check_write = lomac_vnode_check_write,
3058 	.mpo_vnode_copy_label = lomac_copy_label,
3059 	.mpo_vnode_create_extattr = lomac_vnode_create_extattr,
3060 	.mpo_vnode_destroy_label = lomac_destroy_label,
3061 	.mpo_vnode_execve_transition = lomac_vnode_execve_transition,
3062 	.mpo_vnode_execve_will_transition = lomac_vnode_execve_will_transition,
3063 	.mpo_vnode_externalize_label = lomac_externalize_label,
3064 	.mpo_vnode_init_label = lomac_init_label,
3065 	.mpo_vnode_internalize_label = lomac_internalize_label,
3066 	.mpo_vnode_relabel = lomac_vnode_relabel,
3067 	.mpo_vnode_setlabel_extattr = lomac_vnode_setlabel_extattr,
3068 };
3069 
3070 MAC_POLICY_SET(&lomac_ops, mac_lomac, "TrustedBSD MAC/LOMAC",
3071     MPC_LOADTIME_FLAG_NOTLATE, &lomac_slot);
3072