xref: /freebsd/sys/security/mac_mls/mac_mls.c (revision 0572ccaa4543b0abef8ef81e384c1d04de9f3da1)
1 /*-
2  * Copyright (c) 1999-2002, 2007-2011 Robert N. M. Watson
3  * Copyright (c) 2001-2005 McAfee, 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 McAfee
10  * Research, the Security Research Division of McAfee, 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  * This software was developed at the University of Cambridge Computer
18  * Laboratory with support from a grant from Google, Inc.
19  *
20  * Redistribution and use in source and binary forms, with or without
21  * modification, are permitted provided that the following conditions
22  * are met:
23  * 1. Redistributions of source code must retain the above copyright
24  *    notice, this list of conditions and the following disclaimer.
25  * 2. Redistributions in binary form must reproduce the above copyright
26  *    notice, this list of conditions and the following disclaimer in the
27  *    documentation and/or other materials provided with the distribution.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  * $FreeBSD$
42  */
43 
44 /*
45  * Developed by the TrustedBSD Project.
46  *
47  * MLS fixed label mandatory confidentiality policy.
48  */
49 
50 #include <sys/types.h>
51 #include <sys/param.h>
52 #include <sys/acl.h>
53 #include <sys/conf.h>
54 #include <sys/extattr.h>
55 #include <sys/kernel.h>
56 #include <sys/ksem.h>
57 #include <sys/mman.h>
58 #include <sys/malloc.h>
59 #include <sys/mount.h>
60 #include <sys/proc.h>
61 #include <sys/sbuf.h>
62 #include <sys/systm.h>
63 #include <sys/sysproto.h>
64 #include <sys/sysent.h>
65 #include <sys/systm.h>
66 #include <sys/vnode.h>
67 #include <sys/file.h>
68 #include <sys/socket.h>
69 #include <sys/socketvar.h>
70 #include <sys/pipe.h>
71 #include <sys/sx.h>
72 #include <sys/sysctl.h>
73 #include <sys/msg.h>
74 #include <sys/sem.h>
75 #include <sys/shm.h>
76 
77 #include <fs/devfs/devfs.h>
78 
79 #include <net/bpfdesc.h>
80 #include <net/if.h>
81 #include <net/if_types.h>
82 #include <net/if_var.h>
83 
84 #include <netinet/in.h>
85 #include <netinet/in_pcb.h>
86 #include <netinet/ip_var.h>
87 
88 #include <vm/uma.h>
89 #include <vm/vm.h>
90 
91 #include <security/mac/mac_policy.h>
92 #include <security/mac_mls/mac_mls.h>
93 
94 SYSCTL_DECL(_security_mac);
95 
96 static SYSCTL_NODE(_security_mac, OID_AUTO, mls, CTLFLAG_RW, 0,
97     "TrustedBSD mac_mls policy controls");
98 
99 static int	mls_label_size = sizeof(struct mac_mls);
100 SYSCTL_INT(_security_mac_mls, OID_AUTO, label_size, CTLFLAG_RD,
101     &mls_label_size, 0, "Size of struct mac_mls");
102 
103 static int	mls_enabled = 1;
104 SYSCTL_INT(_security_mac_mls, OID_AUTO, enabled, CTLFLAG_RW, &mls_enabled, 0,
105     "Enforce MAC/MLS policy");
106 TUNABLE_INT("security.mac.mls.enabled", &mls_enabled);
107 
108 static int	destroyed_not_inited;
109 SYSCTL_INT(_security_mac_mls, OID_AUTO, destroyed_not_inited, CTLFLAG_RD,
110     &destroyed_not_inited, 0, "Count of labels destroyed but not inited");
111 
112 static int	ptys_equal = 0;
113 SYSCTL_INT(_security_mac_mls, OID_AUTO, ptys_equal, CTLFLAG_RW,
114     &ptys_equal, 0, "Label pty devices as mls/equal on create");
115 TUNABLE_INT("security.mac.mls.ptys_equal", &ptys_equal);
116 
117 static int	revocation_enabled = 0;
118 SYSCTL_INT(_security_mac_mls, OID_AUTO, revocation_enabled, CTLFLAG_RW,
119     &revocation_enabled, 0, "Revoke access to objects on relabel");
120 TUNABLE_INT("security.mac.mls.revocation_enabled", &revocation_enabled);
121 
122 static int	max_compartments = MAC_MLS_MAX_COMPARTMENTS;
123 SYSCTL_INT(_security_mac_mls, OID_AUTO, max_compartments, CTLFLAG_RD,
124     &max_compartments, 0, "Maximum compartments the policy supports");
125 
126 static int	mls_slot;
127 #define	SLOT(l)	((struct mac_mls *)mac_label_get((l), mls_slot))
128 #define	SLOT_SET(l, val) mac_label_set((l), mls_slot, (uintptr_t)(val))
129 
130 static uma_zone_t	zone_mls;
131 
132 static __inline int
133 mls_bit_set_empty(u_char *set) {
134 	int i;
135 
136 	for (i = 0; i < MAC_MLS_MAX_COMPARTMENTS >> 3; i++)
137 		if (set[i] != 0)
138 			return (0);
139 	return (1);
140 }
141 
142 static struct mac_mls *
143 mls_alloc(int flag)
144 {
145 
146 	return (uma_zalloc(zone_mls, flag | M_ZERO));
147 }
148 
149 static void
150 mls_free(struct mac_mls *mm)
151 {
152 
153 	if (mm != NULL)
154 		uma_zfree(zone_mls, mm);
155 	else
156 		atomic_add_int(&destroyed_not_inited, 1);
157 }
158 
159 static int
160 mls_atmostflags(struct mac_mls *mm, int flags)
161 {
162 
163 	if ((mm->mm_flags & flags) != mm->mm_flags)
164 		return (EINVAL);
165 	return (0);
166 }
167 
168 static int
169 mls_dominate_element(struct mac_mls_element *a, struct mac_mls_element *b)
170 {
171 	int bit;
172 
173 	switch (a->mme_type) {
174 	case MAC_MLS_TYPE_EQUAL:
175 	case MAC_MLS_TYPE_HIGH:
176 		return (1);
177 
178 	case MAC_MLS_TYPE_LOW:
179 		switch (b->mme_type) {
180 		case MAC_MLS_TYPE_LEVEL:
181 		case MAC_MLS_TYPE_HIGH:
182 			return (0);
183 
184 		case MAC_MLS_TYPE_EQUAL:
185 		case MAC_MLS_TYPE_LOW:
186 			return (1);
187 
188 		default:
189 			panic("mls_dominate_element: b->mme_type invalid");
190 		}
191 
192 	case MAC_MLS_TYPE_LEVEL:
193 		switch (b->mme_type) {
194 		case MAC_MLS_TYPE_EQUAL:
195 		case MAC_MLS_TYPE_LOW:
196 			return (1);
197 
198 		case MAC_MLS_TYPE_HIGH:
199 			return (0);
200 
201 		case MAC_MLS_TYPE_LEVEL:
202 			for (bit = 1; bit <= MAC_MLS_MAX_COMPARTMENTS; bit++)
203 				if (!MAC_MLS_BIT_TEST(bit,
204 				    a->mme_compartments) &&
205 				    MAC_MLS_BIT_TEST(bit, b->mme_compartments))
206 					return (0);
207 			return (a->mme_level >= b->mme_level);
208 
209 		default:
210 			panic("mls_dominate_element: b->mme_type invalid");
211 		}
212 
213 	default:
214 		panic("mls_dominate_element: a->mme_type invalid");
215 	}
216 
217 	return (0);
218 }
219 
220 static int
221 mls_range_in_range(struct mac_mls *rangea, struct mac_mls *rangeb)
222 {
223 
224 	return (mls_dominate_element(&rangeb->mm_rangehigh,
225 	    &rangea->mm_rangehigh) &&
226 	    mls_dominate_element(&rangea->mm_rangelow,
227 	    &rangeb->mm_rangelow));
228 }
229 
230 static int
231 mls_effective_in_range(struct mac_mls *effective, struct mac_mls *range)
232 {
233 
234 	KASSERT((effective->mm_flags & MAC_MLS_FLAG_EFFECTIVE) != 0,
235 	    ("mls_effective_in_range: a not effective"));
236 	KASSERT((range->mm_flags & MAC_MLS_FLAG_RANGE) != 0,
237 	    ("mls_effective_in_range: b not range"));
238 
239 	return (mls_dominate_element(&range->mm_rangehigh,
240 	    &effective->mm_effective) &&
241 	    mls_dominate_element(&effective->mm_effective,
242 	    &range->mm_rangelow));
243 
244 	return (1);
245 }
246 
247 static int
248 mls_dominate_effective(struct mac_mls *a, struct mac_mls *b)
249 {
250 	KASSERT((a->mm_flags & MAC_MLS_FLAG_EFFECTIVE) != 0,
251 	    ("mls_dominate_effective: a not effective"));
252 	KASSERT((b->mm_flags & MAC_MLS_FLAG_EFFECTIVE) != 0,
253 	    ("mls_dominate_effective: b not effective"));
254 
255 	return (mls_dominate_element(&a->mm_effective, &b->mm_effective));
256 }
257 
258 static int
259 mls_equal_element(struct mac_mls_element *a, struct mac_mls_element *b)
260 {
261 
262 	if (a->mme_type == MAC_MLS_TYPE_EQUAL ||
263 	    b->mme_type == MAC_MLS_TYPE_EQUAL)
264 		return (1);
265 
266 	return (a->mme_type == b->mme_type && a->mme_level == b->mme_level);
267 }
268 
269 static int
270 mls_equal_effective(struct mac_mls *a, struct mac_mls *b)
271 {
272 
273 	KASSERT((a->mm_flags & MAC_MLS_FLAG_EFFECTIVE) != 0,
274 	    ("mls_equal_effective: a not effective"));
275 	KASSERT((b->mm_flags & MAC_MLS_FLAG_EFFECTIVE) != 0,
276 	    ("mls_equal_effective: b not effective"));
277 
278 	return (mls_equal_element(&a->mm_effective, &b->mm_effective));
279 }
280 
281 static int
282 mls_contains_equal(struct mac_mls *mm)
283 {
284 
285 	if (mm->mm_flags & MAC_MLS_FLAG_EFFECTIVE)
286 		if (mm->mm_effective.mme_type == MAC_MLS_TYPE_EQUAL)
287 			return (1);
288 
289 	if (mm->mm_flags & MAC_MLS_FLAG_RANGE) {
290 		if (mm->mm_rangelow.mme_type == MAC_MLS_TYPE_EQUAL)
291 			return (1);
292 		if (mm->mm_rangehigh.mme_type == MAC_MLS_TYPE_EQUAL)
293 			return (1);
294 	}
295 
296 	return (0);
297 }
298 
299 static int
300 mls_subject_privileged(struct mac_mls *mm)
301 {
302 
303 	KASSERT((mm->mm_flags & MAC_MLS_FLAGS_BOTH) == MAC_MLS_FLAGS_BOTH,
304 	    ("mls_subject_privileged: subject doesn't have both labels"));
305 
306 	/* If the effective is EQUAL, it's ok. */
307 	if (mm->mm_effective.mme_type == MAC_MLS_TYPE_EQUAL)
308 		return (0);
309 
310 	/* If either range endpoint is EQUAL, it's ok. */
311 	if (mm->mm_rangelow.mme_type == MAC_MLS_TYPE_EQUAL ||
312 	    mm->mm_rangehigh.mme_type == MAC_MLS_TYPE_EQUAL)
313 		return (0);
314 
315 	/* If the range is low-high, it's ok. */
316 	if (mm->mm_rangelow.mme_type == MAC_MLS_TYPE_LOW &&
317 	    mm->mm_rangehigh.mme_type == MAC_MLS_TYPE_HIGH)
318 		return (0);
319 
320 	/* It's not ok. */
321 	return (EPERM);
322 }
323 
324 static int
325 mls_valid(struct mac_mls *mm)
326 {
327 
328 	if (mm->mm_flags & MAC_MLS_FLAG_EFFECTIVE) {
329 		switch (mm->mm_effective.mme_type) {
330 		case MAC_MLS_TYPE_LEVEL:
331 			break;
332 
333 		case MAC_MLS_TYPE_EQUAL:
334 		case MAC_MLS_TYPE_HIGH:
335 		case MAC_MLS_TYPE_LOW:
336 			if (mm->mm_effective.mme_level != 0 ||
337 			    !MAC_MLS_BIT_SET_EMPTY(
338 			    mm->mm_effective.mme_compartments))
339 				return (EINVAL);
340 			break;
341 
342 		default:
343 			return (EINVAL);
344 		}
345 	} else {
346 		if (mm->mm_effective.mme_type != MAC_MLS_TYPE_UNDEF)
347 			return (EINVAL);
348 	}
349 
350 	if (mm->mm_flags & MAC_MLS_FLAG_RANGE) {
351 		switch (mm->mm_rangelow.mme_type) {
352 		case MAC_MLS_TYPE_LEVEL:
353 			break;
354 
355 		case MAC_MLS_TYPE_EQUAL:
356 		case MAC_MLS_TYPE_HIGH:
357 		case MAC_MLS_TYPE_LOW:
358 			if (mm->mm_rangelow.mme_level != 0 ||
359 			    !MAC_MLS_BIT_SET_EMPTY(
360 			    mm->mm_rangelow.mme_compartments))
361 				return (EINVAL);
362 			break;
363 
364 		default:
365 			return (EINVAL);
366 		}
367 
368 		switch (mm->mm_rangehigh.mme_type) {
369 		case MAC_MLS_TYPE_LEVEL:
370 			break;
371 
372 		case MAC_MLS_TYPE_EQUAL:
373 		case MAC_MLS_TYPE_HIGH:
374 		case MAC_MLS_TYPE_LOW:
375 			if (mm->mm_rangehigh.mme_level != 0 ||
376 			    !MAC_MLS_BIT_SET_EMPTY(
377 			    mm->mm_rangehigh.mme_compartments))
378 				return (EINVAL);
379 			break;
380 
381 		default:
382 			return (EINVAL);
383 		}
384 		if (!mls_dominate_element(&mm->mm_rangehigh,
385 		    &mm->mm_rangelow))
386 			return (EINVAL);
387 	} else {
388 		if (mm->mm_rangelow.mme_type != MAC_MLS_TYPE_UNDEF ||
389 		    mm->mm_rangehigh.mme_type != MAC_MLS_TYPE_UNDEF)
390 			return (EINVAL);
391 	}
392 
393 	return (0);
394 }
395 
396 static void
397 mls_set_range(struct mac_mls *mm, u_short typelow, u_short levellow,
398     u_char *compartmentslow, u_short typehigh, u_short levelhigh,
399     u_char *compartmentshigh)
400 {
401 
402 	mm->mm_rangelow.mme_type = typelow;
403 	mm->mm_rangelow.mme_level = levellow;
404 	if (compartmentslow != NULL)
405 		memcpy(mm->mm_rangelow.mme_compartments, compartmentslow,
406 		    sizeof(mm->mm_rangelow.mme_compartments));
407 	mm->mm_rangehigh.mme_type = typehigh;
408 	mm->mm_rangehigh.mme_level = levelhigh;
409 	if (compartmentshigh != NULL)
410 		memcpy(mm->mm_rangehigh.mme_compartments, compartmentshigh,
411 		    sizeof(mm->mm_rangehigh.mme_compartments));
412 	mm->mm_flags |= MAC_MLS_FLAG_RANGE;
413 }
414 
415 static void
416 mls_set_effective(struct mac_mls *mm, u_short type, u_short level,
417     u_char *compartments)
418 {
419 
420 	mm->mm_effective.mme_type = type;
421 	mm->mm_effective.mme_level = level;
422 	if (compartments != NULL)
423 		memcpy(mm->mm_effective.mme_compartments, compartments,
424 		    sizeof(mm->mm_effective.mme_compartments));
425 	mm->mm_flags |= MAC_MLS_FLAG_EFFECTIVE;
426 }
427 
428 static void
429 mls_copy_range(struct mac_mls *labelfrom, struct mac_mls *labelto)
430 {
431 
432 	KASSERT((labelfrom->mm_flags & MAC_MLS_FLAG_RANGE) != 0,
433 	    ("mls_copy_range: labelfrom not range"));
434 
435 	labelto->mm_rangelow = labelfrom->mm_rangelow;
436 	labelto->mm_rangehigh = labelfrom->mm_rangehigh;
437 	labelto->mm_flags |= MAC_MLS_FLAG_RANGE;
438 }
439 
440 static void
441 mls_copy_effective(struct mac_mls *labelfrom, struct mac_mls *labelto)
442 {
443 
444 	KASSERT((labelfrom->mm_flags & MAC_MLS_FLAG_EFFECTIVE) != 0,
445 	    ("mls_copy_effective: labelfrom not effective"));
446 
447 	labelto->mm_effective = labelfrom->mm_effective;
448 	labelto->mm_flags |= MAC_MLS_FLAG_EFFECTIVE;
449 }
450 
451 static void
452 mls_copy(struct mac_mls *source, struct mac_mls *dest)
453 {
454 
455 	if (source->mm_flags & MAC_MLS_FLAG_EFFECTIVE)
456 		mls_copy_effective(source, dest);
457 	if (source->mm_flags & MAC_MLS_FLAG_RANGE)
458 		mls_copy_range(source, dest);
459 }
460 
461 /*
462  * Policy module operations.
463  */
464 static void
465 mls_init(struct mac_policy_conf *conf)
466 {
467 
468 	zone_mls = uma_zcreate("mac_mls", sizeof(struct mac_mls), NULL,
469 	    NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
470 }
471 
472 /*
473  * Label operations.
474  */
475 static void
476 mls_init_label(struct label *label)
477 {
478 
479 	SLOT_SET(label, mls_alloc(M_WAITOK));
480 }
481 
482 static int
483 mls_init_label_waitcheck(struct label *label, int flag)
484 {
485 
486 	SLOT_SET(label, mls_alloc(flag));
487 	if (SLOT(label) == NULL)
488 		return (ENOMEM);
489 
490 	return (0);
491 }
492 
493 static void
494 mls_destroy_label(struct label *label)
495 {
496 
497 	mls_free(SLOT(label));
498 	SLOT_SET(label, NULL);
499 }
500 
501 /*
502  * mls_element_to_string() accepts an sbuf and MLS element.  It converts the
503  * MLS element to a string and stores the result in the sbuf; if there isn't
504  * space in the sbuf, -1 is returned.
505  */
506 static int
507 mls_element_to_string(struct sbuf *sb, struct mac_mls_element *element)
508 {
509 	int i, first;
510 
511 	switch (element->mme_type) {
512 	case MAC_MLS_TYPE_HIGH:
513 		return (sbuf_printf(sb, "high"));
514 
515 	case MAC_MLS_TYPE_LOW:
516 		return (sbuf_printf(sb, "low"));
517 
518 	case MAC_MLS_TYPE_EQUAL:
519 		return (sbuf_printf(sb, "equal"));
520 
521 	case MAC_MLS_TYPE_LEVEL:
522 		if (sbuf_printf(sb, "%d", element->mme_level) == -1)
523 			return (-1);
524 
525 		first = 1;
526 		for (i = 1; i <= MAC_MLS_MAX_COMPARTMENTS; i++) {
527 			if (MAC_MLS_BIT_TEST(i, element->mme_compartments)) {
528 				if (first) {
529 					if (sbuf_putc(sb, ':') == -1)
530 						return (-1);
531 					if (sbuf_printf(sb, "%d", i) == -1)
532 						return (-1);
533 					first = 0;
534 				} else {
535 					if (sbuf_printf(sb, "+%d", i) == -1)
536 						return (-1);
537 				}
538 			}
539 		}
540 		return (0);
541 
542 	default:
543 		panic("mls_element_to_string: invalid type (%d)",
544 		    element->mme_type);
545 	}
546 }
547 
548 /*
549  * mls_to_string() converts an MLS label to a string, and places the results
550  * in the passed sbuf.  It returns 0 on success, or EINVAL if there isn't
551  * room in the sbuf.  Note: the sbuf will be modified even in a failure case,
552  * so the caller may need to revert the sbuf by restoring the offset if
553  * that's undesired.
554  */
555 static int
556 mls_to_string(struct sbuf *sb, struct mac_mls *mm)
557 {
558 
559 	if (mm->mm_flags & MAC_MLS_FLAG_EFFECTIVE) {
560 		if (mls_element_to_string(sb, &mm->mm_effective) == -1)
561 			return (EINVAL);
562 	}
563 
564 	if (mm->mm_flags & MAC_MLS_FLAG_RANGE) {
565 		if (sbuf_putc(sb, '(') == -1)
566 			return (EINVAL);
567 
568 		if (mls_element_to_string(sb, &mm->mm_rangelow) == -1)
569 			return (EINVAL);
570 
571 		if (sbuf_putc(sb, '-') == -1)
572 			return (EINVAL);
573 
574 		if (mls_element_to_string(sb, &mm->mm_rangehigh) == -1)
575 			return (EINVAL);
576 
577 		if (sbuf_putc(sb, ')') == -1)
578 			return (EINVAL);
579 	}
580 
581 	return (0);
582 }
583 
584 static int
585 mls_externalize_label(struct label *label, char *element_name,
586     struct sbuf *sb, int *claimed)
587 {
588 	struct mac_mls *mm;
589 
590 	if (strcmp(MAC_MLS_LABEL_NAME, element_name) != 0)
591 		return (0);
592 
593 	(*claimed)++;
594 
595 	mm = SLOT(label);
596 
597 	return (mls_to_string(sb, mm));
598 }
599 
600 static int
601 mls_parse_element(struct mac_mls_element *element, char *string)
602 {
603 	char *compartment, *end, *level;
604 	int value;
605 
606 	if (strcmp(string, "high") == 0 || strcmp(string, "hi") == 0) {
607 		element->mme_type = MAC_MLS_TYPE_HIGH;
608 		element->mme_level = MAC_MLS_TYPE_UNDEF;
609 	} else if (strcmp(string, "low") == 0 || strcmp(string, "lo") == 0) {
610 		element->mme_type = MAC_MLS_TYPE_LOW;
611 		element->mme_level = MAC_MLS_TYPE_UNDEF;
612 	} else if (strcmp(string, "equal") == 0 ||
613 	    strcmp(string, "eq") == 0) {
614 		element->mme_type = MAC_MLS_TYPE_EQUAL;
615 		element->mme_level = MAC_MLS_TYPE_UNDEF;
616 	} else {
617 		element->mme_type = MAC_MLS_TYPE_LEVEL;
618 
619 		/*
620 		 * Numeric level piece of the element.
621 		 */
622 		level = strsep(&string, ":");
623 		value = strtol(level, &end, 10);
624 		if (end == level || *end != '\0')
625 			return (EINVAL);
626 		if (value < 0 || value > 65535)
627 			return (EINVAL);
628 		element->mme_level = value;
629 
630 		/*
631 		 * Optional compartment piece of the element.  If none are
632 		 * included, we assume that the label has no compartments.
633 		 */
634 		if (string == NULL)
635 			return (0);
636 		if (*string == '\0')
637 			return (0);
638 
639 		while ((compartment = strsep(&string, "+")) != NULL) {
640 			value = strtol(compartment, &end, 10);
641 			if (compartment == end || *end != '\0')
642 				return (EINVAL);
643 			if (value < 1 || value > MAC_MLS_MAX_COMPARTMENTS)
644 				return (EINVAL);
645 			MAC_MLS_BIT_SET(value, element->mme_compartments);
646 		}
647 	}
648 
649 	return (0);
650 }
651 
652 /*
653  * Note: destructively consumes the string, make a local copy before calling
654  * if that's a problem.
655  */
656 static int
657 mls_parse(struct mac_mls *mm, char *string)
658 {
659 	char *rangehigh, *rangelow, *effective;
660 	int error;
661 
662 	effective = strsep(&string, "(");
663 	if (*effective == '\0')
664 		effective = NULL;
665 
666 	if (string != NULL) {
667 		rangelow = strsep(&string, "-");
668 		if (string == NULL)
669 			return (EINVAL);
670 		rangehigh = strsep(&string, ")");
671 		if (string == NULL)
672 			return (EINVAL);
673 		if (*string != '\0')
674 			return (EINVAL);
675 	} else {
676 		rangelow = NULL;
677 		rangehigh = NULL;
678 	}
679 
680 	KASSERT((rangelow != NULL && rangehigh != NULL) ||
681 	    (rangelow == NULL && rangehigh == NULL),
682 	    ("mls_parse: range mismatch"));
683 
684 	bzero(mm, sizeof(*mm));
685 	if (effective != NULL) {
686 		error = mls_parse_element(&mm->mm_effective, effective);
687 		if (error)
688 			return (error);
689 		mm->mm_flags |= MAC_MLS_FLAG_EFFECTIVE;
690 	}
691 
692 	if (rangelow != NULL) {
693 		error = mls_parse_element(&mm->mm_rangelow, rangelow);
694 		if (error)
695 			return (error);
696 		error = mls_parse_element(&mm->mm_rangehigh, rangehigh);
697 		if (error)
698 			return (error);
699 		mm->mm_flags |= MAC_MLS_FLAG_RANGE;
700 	}
701 
702 	error = mls_valid(mm);
703 	if (error)
704 		return (error);
705 
706 	return (0);
707 }
708 
709 static int
710 mls_internalize_label(struct label *label, char *element_name,
711     char *element_data, int *claimed)
712 {
713 	struct mac_mls *mm, mm_temp;
714 	int error;
715 
716 	if (strcmp(MAC_MLS_LABEL_NAME, element_name) != 0)
717 		return (0);
718 
719 	(*claimed)++;
720 
721 	error = mls_parse(&mm_temp, element_data);
722 	if (error)
723 		return (error);
724 
725 	mm = SLOT(label);
726 	*mm = mm_temp;
727 
728 	return (0);
729 }
730 
731 static void
732 mls_copy_label(struct label *src, struct label *dest)
733 {
734 
735 	*SLOT(dest) = *SLOT(src);
736 }
737 
738 /*
739  * Object-specific entry point implementations are sorted alphabetically by
740  * object type name and then by operation.
741  */
742 static int
743 mls_bpfdesc_check_receive(struct bpf_d *d, struct label *dlabel,
744      struct ifnet *ifp, struct label *ifplabel)
745 {
746 	struct mac_mls *a, *b;
747 
748 	if (!mls_enabled)
749 		return (0);
750 
751 	a = SLOT(dlabel);
752 	b = SLOT(ifplabel);
753 
754 	if (mls_equal_effective(a, b))
755 		return (0);
756 	return (EACCES);
757 }
758 
759 static void
760 mls_bpfdesc_create(struct ucred *cred, struct bpf_d *d, struct label *dlabel)
761 {
762 	struct mac_mls *source, *dest;
763 
764 	source = SLOT(cred->cr_label);
765 	dest = SLOT(dlabel);
766 
767 	mls_copy_effective(source, dest);
768 }
769 
770 static void
771 mls_bpfdesc_create_mbuf(struct bpf_d *d, struct label *dlabel,
772     struct mbuf *m, struct label *mlabel)
773 {
774 	struct mac_mls *source, *dest;
775 
776 	source = SLOT(dlabel);
777 	dest = SLOT(mlabel);
778 
779 	mls_copy_effective(source, dest);
780 }
781 
782 static void
783 mls_cred_associate_nfsd(struct ucred *cred)
784 {
785 	struct mac_mls *label;
786 
787 	label = SLOT(cred->cr_label);
788 	mls_set_effective(label, MAC_MLS_TYPE_LOW, 0, NULL);
789 	mls_set_range(label, MAC_MLS_TYPE_LOW, 0, NULL, MAC_MLS_TYPE_HIGH, 0,
790 	    NULL);
791 }
792 
793 static int
794 mls_cred_check_relabel(struct ucred *cred, struct label *newlabel)
795 {
796 	struct mac_mls *subj, *new;
797 	int error;
798 
799 	subj = SLOT(cred->cr_label);
800 	new = SLOT(newlabel);
801 
802 	/*
803 	 * If there is an MLS label update for the credential, it may be an
804 	 * update of effective, range, or both.
805 	 */
806 	error = mls_atmostflags(new, MAC_MLS_FLAGS_BOTH);
807 	if (error)
808 		return (error);
809 
810 	/*
811 	 * If the MLS label is to be changed, authorize as appropriate.
812 	 */
813 	if (new->mm_flags & MAC_MLS_FLAGS_BOTH) {
814 		/*
815 		 * If the change request modifies both the MLS label
816 		 * effective and range, check that the new effective will be
817 		 * in the new range.
818 		 */
819 		if ((new->mm_flags & MAC_MLS_FLAGS_BOTH) ==
820 		    MAC_MLS_FLAGS_BOTH && !mls_effective_in_range(new, new))
821 			return (EINVAL);
822 
823 		/*
824 		 * To change the MLS effective label on a credential, the new
825 		 * effective label must be in the current range.
826 		 */
827 		if (new->mm_flags & MAC_MLS_FLAG_EFFECTIVE &&
828 		    !mls_effective_in_range(new, subj))
829 			return (EPERM);
830 
831 		/*
832 		 * To change the MLS range label on a credential, the new
833 		 * range must be in the current range.
834 		 */
835 		if (new->mm_flags & MAC_MLS_FLAG_RANGE &&
836 		    !mls_range_in_range(new, subj))
837 			return (EPERM);
838 
839 		/*
840 		 * To have EQUAL in any component of the new credential MLS
841 		 * label, the subject must already have EQUAL in their label.
842 		 */
843 		if (mls_contains_equal(new)) {
844 			error = mls_subject_privileged(subj);
845 			if (error)
846 				return (error);
847 		}
848 	}
849 
850 	return (0);
851 }
852 
853 static int
854 mls_cred_check_visible(struct ucred *cr1, struct ucred *cr2)
855 {
856 	struct mac_mls *subj, *obj;
857 
858 	if (!mls_enabled)
859 		return (0);
860 
861 	subj = SLOT(cr1->cr_label);
862 	obj = SLOT(cr2->cr_label);
863 
864 	/* XXX: range */
865 	if (!mls_dominate_effective(subj, obj))
866 		return (ESRCH);
867 
868 	return (0);
869 }
870 
871 static void
872 mls_cred_create_init(struct ucred *cred)
873 {
874 	struct mac_mls *dest;
875 
876 	dest = SLOT(cred->cr_label);
877 
878 	mls_set_effective(dest, MAC_MLS_TYPE_LOW, 0, NULL);
879 	mls_set_range(dest, MAC_MLS_TYPE_LOW, 0, NULL, MAC_MLS_TYPE_HIGH, 0,
880 	    NULL);
881 }
882 
883 static void
884 mls_cred_create_swapper(struct ucred *cred)
885 {
886 	struct mac_mls *dest;
887 
888 	dest = SLOT(cred->cr_label);
889 
890 	mls_set_effective(dest, MAC_MLS_TYPE_EQUAL, 0, NULL);
891 	mls_set_range(dest, MAC_MLS_TYPE_LOW, 0, NULL, MAC_MLS_TYPE_HIGH, 0,
892 	    NULL);
893 }
894 
895 static void
896 mls_cred_relabel(struct ucred *cred, struct label *newlabel)
897 {
898 	struct mac_mls *source, *dest;
899 
900 	source = SLOT(newlabel);
901 	dest = SLOT(cred->cr_label);
902 
903 	mls_copy(source, dest);
904 }
905 
906 static void
907 mls_devfs_create_device(struct ucred *cred, struct mount *mp,
908     struct cdev *dev, struct devfs_dirent *de, struct label *delabel)
909 {
910 	struct mac_mls *mm;
911 	const char *dn;
912 	int mls_type;
913 
914 	mm = SLOT(delabel);
915 	dn = devtoname(dev);
916 	if (strcmp(dn, "null") == 0 ||
917 	    strcmp(dn, "zero") == 0 ||
918 	    strcmp(dn, "random") == 0 ||
919 	    strncmp(dn, "fd/", strlen("fd/")) == 0)
920 		mls_type = MAC_MLS_TYPE_EQUAL;
921 	else if (strcmp(dn, "kmem") == 0 ||
922 	    strcmp(dn, "mem") == 0)
923 		mls_type = MAC_MLS_TYPE_HIGH;
924 	else if (ptys_equal &&
925 	    (strncmp(dn, "ttyp", strlen("ttyp")) == 0 ||
926 	    strncmp(dn, "pts/", strlen("pts/")) == 0 ||
927 	    strncmp(dn, "ptyp", strlen("ptyp")) == 0))
928 		mls_type = MAC_MLS_TYPE_EQUAL;
929 	else
930 		mls_type = MAC_MLS_TYPE_LOW;
931 	mls_set_effective(mm, mls_type, 0, NULL);
932 }
933 
934 static void
935 mls_devfs_create_directory(struct mount *mp, char *dirname, int dirnamelen,
936     struct devfs_dirent *de, struct label *delabel)
937 {
938 	struct mac_mls *mm;
939 
940 	mm = SLOT(delabel);
941 	mls_set_effective(mm, MAC_MLS_TYPE_LOW, 0, NULL);
942 }
943 
944 static void
945 mls_devfs_create_symlink(struct ucred *cred, struct mount *mp,
946     struct devfs_dirent *dd, struct label *ddlabel, struct devfs_dirent *de,
947     struct label *delabel)
948 {
949 	struct mac_mls *source, *dest;
950 
951 	source = SLOT(cred->cr_label);
952 	dest = SLOT(delabel);
953 
954 	mls_copy_effective(source, dest);
955 }
956 
957 static void
958 mls_devfs_update(struct mount *mp, struct devfs_dirent *de,
959     struct label *delabel, struct vnode *vp, struct label *vplabel)
960 {
961 	struct mac_mls *source, *dest;
962 
963 	source = SLOT(vplabel);
964 	dest = SLOT(delabel);
965 
966 	mls_copy_effective(source, dest);
967 }
968 
969 static void
970 mls_devfs_vnode_associate(struct mount *mp, struct label *mplabel,
971     struct devfs_dirent *de, struct label *delabel, struct vnode *vp,
972     struct label *vplabel)
973 {
974 	struct mac_mls *source, *dest;
975 
976 	source = SLOT(delabel);
977 	dest = SLOT(vplabel);
978 
979 	mls_copy_effective(source, dest);
980 }
981 
982 static int
983 mls_ifnet_check_relabel(struct ucred *cred, struct ifnet *ifp,
984     struct label *ifplabel, struct label *newlabel)
985 {
986 	struct mac_mls *subj, *new;
987 	int error;
988 
989 	subj = SLOT(cred->cr_label);
990 	new = SLOT(newlabel);
991 
992 	/*
993 	 * If there is an MLS label update for the interface, it may be an
994 	 * update of effective, range, or both.
995 	 */
996 	error = mls_atmostflags(new, MAC_MLS_FLAGS_BOTH);
997 	if (error)
998 		return (error);
999 
1000 	/*
1001 	 * Relabeling network interfaces requires MLS privilege.
1002 	 */
1003 	return (mls_subject_privileged(subj));
1004 }
1005 
1006 static int
1007 mls_ifnet_check_transmit(struct ifnet *ifp, struct label *ifplabel,
1008     struct mbuf *m, struct label *mlabel)
1009 {
1010 	struct mac_mls *p, *i;
1011 
1012 	if (!mls_enabled)
1013 		return (0);
1014 
1015 	p = SLOT(mlabel);
1016 	i = SLOT(ifplabel);
1017 
1018 	return (mls_effective_in_range(p, i) ? 0 : EACCES);
1019 }
1020 
1021 static void
1022 mls_ifnet_create(struct ifnet *ifp, struct label *ifplabel)
1023 {
1024 	struct mac_mls *dest;
1025 	int type;
1026 
1027 	dest = SLOT(ifplabel);
1028 
1029 	if (ifp->if_type == IFT_LOOP)
1030 		type = MAC_MLS_TYPE_EQUAL;
1031 	else
1032 		type = MAC_MLS_TYPE_LOW;
1033 
1034 	mls_set_effective(dest, type, 0, NULL);
1035 	mls_set_range(dest, type, 0, NULL, type, 0, NULL);
1036 }
1037 
1038 static void
1039 mls_ifnet_create_mbuf(struct ifnet *ifp, struct label *ifplabel,
1040     struct mbuf *m, struct label *mlabel)
1041 {
1042 	struct mac_mls *source, *dest;
1043 
1044 	source = SLOT(ifplabel);
1045 	dest = SLOT(mlabel);
1046 
1047 	mls_copy_effective(source, dest);
1048 }
1049 
1050 static void
1051 mls_ifnet_relabel(struct ucred *cred, struct ifnet *ifp,
1052     struct label *ifplabel, struct label *newlabel)
1053 {
1054 	struct mac_mls *source, *dest;
1055 
1056 	source = SLOT(newlabel);
1057 	dest = SLOT(ifplabel);
1058 
1059 	mls_copy(source, dest);
1060 }
1061 
1062 static int
1063 mls_inpcb_check_deliver(struct inpcb *inp, struct label *inplabel,
1064     struct mbuf *m, struct label *mlabel)
1065 {
1066 	struct mac_mls *p, *i;
1067 
1068 	if (!mls_enabled)
1069 		return (0);
1070 
1071 	p = SLOT(mlabel);
1072 	i = SLOT(inplabel);
1073 
1074 	return (mls_equal_effective(p, i) ? 0 : EACCES);
1075 }
1076 
1077 static int
1078 mls_inpcb_check_visible(struct ucred *cred, struct inpcb *inp,
1079     struct label *inplabel)
1080 {
1081 	struct mac_mls *subj, *obj;
1082 
1083 	if (!mls_enabled)
1084 		return (0);
1085 
1086 	subj = SLOT(cred->cr_label);
1087 	obj = SLOT(inplabel);
1088 
1089 	if (!mls_dominate_effective(subj, obj))
1090 		return (ENOENT);
1091 
1092 	return (0);
1093 }
1094 
1095 static void
1096 mls_inpcb_create(struct socket *so, struct label *solabel, struct inpcb *inp,
1097     struct label *inplabel)
1098 {
1099 	struct mac_mls *source, *dest;
1100 
1101 	source = SLOT(solabel);
1102 	dest = SLOT(inplabel);
1103 
1104 	mls_copy_effective(source, dest);
1105 }
1106 
1107 static void
1108 mls_inpcb_create_mbuf(struct inpcb *inp, struct label *inplabel,
1109     struct mbuf *m, struct label *mlabel)
1110 {
1111 	struct mac_mls *source, *dest;
1112 
1113 	source = SLOT(inplabel);
1114 	dest = SLOT(mlabel);
1115 
1116 	mls_copy_effective(source, dest);
1117 }
1118 
1119 static void
1120 mls_inpcb_sosetlabel(struct socket *so, struct label *solabel,
1121     struct inpcb *inp, struct label *inplabel)
1122 {
1123 	struct mac_mls *source, *dest;
1124 
1125 	SOCK_LOCK_ASSERT(so);
1126 
1127 	source = SLOT(solabel);
1128 	dest = SLOT(inplabel);
1129 
1130 	mls_copy(source, dest);
1131 }
1132 
1133 static void
1134 mls_ip6q_create(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
1135     struct label *q6label)
1136 {
1137 	struct mac_mls *source, *dest;
1138 
1139 	source = SLOT(mlabel);
1140 	dest = SLOT(q6label);
1141 
1142 	mls_copy_effective(source, dest);
1143 }
1144 
1145 static int
1146 mls_ip6q_match(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
1147     struct label *q6label)
1148 {
1149 	struct mac_mls *a, *b;
1150 
1151 	a = SLOT(q6label);
1152 	b = SLOT(mlabel);
1153 
1154 	return (mls_equal_effective(a, b));
1155 }
1156 
1157 static void
1158 mls_ip6q_reassemble(struct ip6q *q6, struct label *q6label, struct mbuf *m,
1159     struct label *mlabel)
1160 {
1161 	struct mac_mls *source, *dest;
1162 
1163 	source = SLOT(q6label);
1164 	dest = SLOT(mlabel);
1165 
1166 	/* Just use the head, since we require them all to match. */
1167 	mls_copy_effective(source, dest);
1168 }
1169 
1170 static void
1171 mls_ip6q_update(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
1172     struct label *q6label)
1173 {
1174 
1175 	/* NOOP: we only accept matching labels, so no need to update */
1176 }
1177 
1178 static void
1179 mls_ipq_create(struct mbuf *m, struct label *mlabel, struct ipq *q,
1180     struct label *qlabel)
1181 {
1182 	struct mac_mls *source, *dest;
1183 
1184 	source = SLOT(mlabel);
1185 	dest = SLOT(qlabel);
1186 
1187 	mls_copy_effective(source, dest);
1188 }
1189 
1190 static int
1191 mls_ipq_match(struct mbuf *m, struct label *mlabel, struct ipq *q,
1192     struct label *qlabel)
1193 {
1194 	struct mac_mls *a, *b;
1195 
1196 	a = SLOT(qlabel);
1197 	b = SLOT(mlabel);
1198 
1199 	return (mls_equal_effective(a, b));
1200 }
1201 
1202 static void
1203 mls_ipq_reassemble(struct ipq *q, struct label *qlabel, struct mbuf *m,
1204     struct label *mlabel)
1205 {
1206 	struct mac_mls *source, *dest;
1207 
1208 	source = SLOT(qlabel);
1209 	dest = SLOT(mlabel);
1210 
1211 	/* Just use the head, since we require them all to match. */
1212 	mls_copy_effective(source, dest);
1213 }
1214 
1215 static void
1216 mls_ipq_update(struct mbuf *m, struct label *mlabel, struct ipq *q,
1217     struct label *qlabel)
1218 {
1219 
1220 	/* NOOP: we only accept matching labels, so no need to update */
1221 }
1222 
1223 static int
1224 mls_mount_check_stat(struct ucred *cred, struct mount *mp,
1225     struct label *mntlabel)
1226 {
1227 	struct mac_mls *subj, *obj;
1228 
1229 	if (!mls_enabled)
1230 		return (0);
1231 
1232 	subj = SLOT(cred->cr_label);
1233 	obj = SLOT(mntlabel);
1234 
1235 	if (!mls_dominate_effective(subj, obj))
1236 		return (EACCES);
1237 
1238 	return (0);
1239 }
1240 
1241 static void
1242 mls_mount_create(struct ucred *cred, struct mount *mp, struct label *mplabel)
1243 {
1244 	struct mac_mls *source, *dest;
1245 
1246 	source = SLOT(cred->cr_label);
1247 	dest = SLOT(mplabel);
1248 
1249 	mls_copy_effective(source, dest);
1250 }
1251 
1252 static void
1253 mls_netinet_arp_send(struct ifnet *ifp, struct label *ifplabel,
1254     struct mbuf *m, struct label *mlabel)
1255 {
1256 	struct mac_mls *dest;
1257 
1258 	dest = SLOT(mlabel);
1259 
1260 	mls_set_effective(dest, MAC_MLS_TYPE_EQUAL, 0, NULL);
1261 }
1262 
1263 static void
1264 mls_netinet_firewall_reply(struct mbuf *mrecv, struct label *mrecvlabel,
1265     struct mbuf *msend, struct label *msendlabel)
1266 {
1267 	struct mac_mls *source, *dest;
1268 
1269 	source = SLOT(mrecvlabel);
1270 	dest = SLOT(msendlabel);
1271 
1272 	mls_copy_effective(source, dest);
1273 }
1274 
1275 static void
1276 mls_netinet_firewall_send(struct mbuf *m, struct label *mlabel)
1277 {
1278 	struct mac_mls *dest;
1279 
1280 	dest = SLOT(mlabel);
1281 
1282 	/* XXX: where is the label for the firewall really comming from? */
1283 	mls_set_effective(dest, MAC_MLS_TYPE_EQUAL, 0, NULL);
1284 }
1285 
1286 static void
1287 mls_netinet_fragment(struct mbuf *m, struct label *mlabel, struct mbuf *frag,
1288     struct label *fraglabel)
1289 {
1290 	struct mac_mls *source, *dest;
1291 
1292 	source = SLOT(mlabel);
1293 	dest = SLOT(fraglabel);
1294 
1295 	mls_copy_effective(source, dest);
1296 }
1297 
1298 static void
1299 mls_netinet_icmp_reply(struct mbuf *mrecv, struct label *mrecvlabel,
1300     struct mbuf *msend, struct label *msendlabel)
1301 {
1302 	struct mac_mls *source, *dest;
1303 
1304 	source = SLOT(mrecvlabel);
1305 	dest = SLOT(msendlabel);
1306 
1307 	mls_copy_effective(source, dest);
1308 }
1309 
1310 static void
1311 mls_netinet_igmp_send(struct ifnet *ifp, struct label *ifplabel,
1312     struct mbuf *m, struct label *mlabel)
1313 {
1314 	struct mac_mls *dest;
1315 
1316 	dest = SLOT(mlabel);
1317 
1318 	mls_set_effective(dest, MAC_MLS_TYPE_EQUAL, 0, NULL);
1319 }
1320 
1321 static void
1322 mls_netinet6_nd6_send(struct ifnet *ifp, struct label *ifplabel,
1323     struct mbuf *m, struct label *mlabel)
1324 {
1325 	struct mac_mls *dest;
1326 
1327 	dest = SLOT(mlabel);
1328 
1329 	mls_set_effective(dest, MAC_MLS_TYPE_EQUAL, 0, NULL);
1330 }
1331 
1332 static int
1333 mls_pipe_check_ioctl(struct ucred *cred, struct pipepair *pp,
1334     struct label *pplabel, unsigned long cmd, void /* caddr_t */ *data)
1335 {
1336 
1337 	if (!mls_enabled)
1338 		return (0);
1339 
1340 	/* XXX: This will be implemented soon... */
1341 
1342 	return (0);
1343 }
1344 
1345 static int
1346 mls_pipe_check_poll(struct ucred *cred, struct pipepair *pp,
1347     struct label *pplabel)
1348 {
1349 	struct mac_mls *subj, *obj;
1350 
1351 	if (!mls_enabled)
1352 		return (0);
1353 
1354 	subj = SLOT(cred->cr_label);
1355 	obj = SLOT(pplabel);
1356 
1357 	if (!mls_dominate_effective(subj, obj))
1358 		return (EACCES);
1359 
1360 	return (0);
1361 }
1362 
1363 static int
1364 mls_pipe_check_read(struct ucred *cred, struct pipepair *pp,
1365     struct label *pplabel)
1366 {
1367 	struct mac_mls *subj, *obj;
1368 
1369 	if (!mls_enabled)
1370 		return (0);
1371 
1372 	subj = SLOT(cred->cr_label);
1373 	obj = SLOT(pplabel);
1374 
1375 	if (!mls_dominate_effective(subj, obj))
1376 		return (EACCES);
1377 
1378 	return (0);
1379 }
1380 
1381 static int
1382 mls_pipe_check_relabel(struct ucred *cred, struct pipepair *pp,
1383     struct label *pplabel, struct label *newlabel)
1384 {
1385 	struct mac_mls *subj, *obj, *new;
1386 	int error;
1387 
1388 	new = SLOT(newlabel);
1389 	subj = SLOT(cred->cr_label);
1390 	obj = SLOT(pplabel);
1391 
1392 	/*
1393 	 * If there is an MLS label update for a pipe, it must be a effective
1394 	 * update.
1395 	 */
1396 	error = mls_atmostflags(new, MAC_MLS_FLAG_EFFECTIVE);
1397 	if (error)
1398 		return (error);
1399 
1400 	/*
1401 	 * To perform a relabel of a pipe (MLS label or not), MLS must
1402 	 * authorize the relabel.
1403 	 */
1404 	if (!mls_effective_in_range(obj, subj))
1405 		return (EPERM);
1406 
1407 	/*
1408 	 * If the MLS label is to be changed, authorize as appropriate.
1409 	 */
1410 	if (new->mm_flags & MAC_MLS_FLAG_EFFECTIVE) {
1411 		/*
1412 		 * To change the MLS label on a pipe, the new pipe label must
1413 		 * be in the subject range.
1414 		 */
1415 		if (!mls_effective_in_range(new, subj))
1416 			return (EPERM);
1417 
1418 		/*
1419 		 * To change the MLS label on a pipe to be EQUAL, the subject
1420 		 * must have appropriate privilege.
1421 		 */
1422 		if (mls_contains_equal(new)) {
1423 			error = mls_subject_privileged(subj);
1424 			if (error)
1425 				return (error);
1426 		}
1427 	}
1428 
1429 	return (0);
1430 }
1431 
1432 static int
1433 mls_pipe_check_stat(struct ucred *cred, struct pipepair *pp,
1434     struct label *pplabel)
1435 {
1436 	struct mac_mls *subj, *obj;
1437 
1438 	if (!mls_enabled)
1439 		return (0);
1440 
1441 	subj = SLOT(cred->cr_label);
1442 	obj = SLOT(pplabel);
1443 
1444 	if (!mls_dominate_effective(subj, obj))
1445 		return (EACCES);
1446 
1447 	return (0);
1448 }
1449 
1450 static int
1451 mls_pipe_check_write(struct ucred *cred, struct pipepair *pp,
1452     struct label *pplabel)
1453 {
1454 	struct mac_mls *subj, *obj;
1455 
1456 	if (!mls_enabled)
1457 		return (0);
1458 
1459 	subj = SLOT(cred->cr_label);
1460 	obj = SLOT(pplabel);
1461 
1462 	if (!mls_dominate_effective(obj, subj))
1463 		return (EACCES);
1464 
1465 	return (0);
1466 }
1467 
1468 static void
1469 mls_pipe_create(struct ucred *cred, struct pipepair *pp,
1470     struct label *pplabel)
1471 {
1472 	struct mac_mls *source, *dest;
1473 
1474 	source = SLOT(cred->cr_label);
1475 	dest = SLOT(pplabel);
1476 
1477 	mls_copy_effective(source, dest);
1478 }
1479 
1480 static void
1481 mls_pipe_relabel(struct ucred *cred, struct pipepair *pp,
1482     struct label *pplabel, struct label *newlabel)
1483 {
1484 	struct mac_mls *source, *dest;
1485 
1486 	source = SLOT(newlabel);
1487 	dest = SLOT(pplabel);
1488 
1489 	mls_copy(source, dest);
1490 }
1491 
1492 static int
1493 mls_posixsem_check_openunlink(struct ucred *cred, struct ksem *ks,
1494     struct label *kslabel)
1495 {
1496 	struct mac_mls *subj, *obj;
1497 
1498 	if (!mls_enabled)
1499 		return (0);
1500 
1501 	subj = SLOT(cred->cr_label);
1502 	obj = SLOT(kslabel);
1503 
1504 	if (!mls_dominate_effective(obj, subj))
1505 		return (EACCES);
1506 
1507 	return (0);
1508 }
1509 
1510 static int
1511 mls_posixsem_check_rdonly(struct ucred *active_cred, struct ucred *file_cred,
1512     struct ksem *ks, struct label *kslabel)
1513 {
1514 	struct mac_mls *subj, *obj;
1515 
1516 	if (!mls_enabled)
1517 		return (0);
1518 
1519 	subj = SLOT(active_cred->cr_label);
1520 	obj = SLOT(kslabel);
1521 
1522 	if (!mls_dominate_effective(subj, obj))
1523 		return (EACCES);
1524 
1525 	return (0);
1526 }
1527 
1528 static int
1529 mls_posixsem_check_setmode(struct ucred *cred, struct ksem *ks,
1530     struct label *shmlabel, mode_t mode)
1531 {
1532 	struct mac_mls *subj, *obj;
1533 
1534 	if (!mls_enabled)
1535 		return (0);
1536 
1537 	subj = SLOT(cred->cr_label);
1538 	obj = SLOT(shmlabel);
1539 
1540 	if (!mls_dominate_effective(obj, subj))
1541 		return (EACCES);
1542 
1543 	return (0);
1544 }
1545 
1546 static int
1547 mls_posixsem_check_setowner(struct ucred *cred, struct ksem *ks,
1548     struct label *shmlabel, uid_t uid, gid_t gid)
1549 {
1550 	struct mac_mls *subj, *obj;
1551 
1552 	if (!mls_enabled)
1553 		return (0);
1554 
1555 	subj = SLOT(cred->cr_label);
1556 	obj = SLOT(shmlabel);
1557 
1558 	if (!mls_dominate_effective(obj, subj))
1559 		return (EACCES);
1560 
1561 	return (0);
1562 }
1563 
1564 static int
1565 mls_posixsem_check_write(struct ucred *active_cred, struct ucred *file_cred,
1566     struct ksem *ks, struct label *kslabel)
1567 {
1568 	struct mac_mls *subj, *obj;
1569 
1570 	if (!mls_enabled)
1571 		return (0);
1572 
1573 	subj = SLOT(active_cred->cr_label);
1574 	obj = SLOT(kslabel);
1575 
1576 	if (!mls_dominate_effective(obj, subj))
1577 		return (EACCES);
1578 
1579 	return (0);
1580 }
1581 
1582 static void
1583 mls_posixsem_create(struct ucred *cred, struct ksem *ks,
1584     struct label *kslabel)
1585 {
1586 	struct mac_mls *source, *dest;
1587 
1588 	source = SLOT(cred->cr_label);
1589 	dest = SLOT(kslabel);
1590 
1591 	mls_copy_effective(source, dest);
1592 }
1593 
1594 static int
1595 mls_posixshm_check_mmap(struct ucred *cred, struct shmfd *shmfd,
1596     struct label *shmlabel, int prot, int flags)
1597 {
1598 	struct mac_mls *subj, *obj;
1599 
1600 	if (!mls_enabled)
1601 		return (0);
1602 
1603 	subj = SLOT(cred->cr_label);
1604 	obj = SLOT(shmlabel);
1605 
1606 	if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
1607 		if (!mls_dominate_effective(subj, obj))
1608 			return (EACCES);
1609 	}
1610 	if (((prot & VM_PROT_WRITE) != 0) && ((flags & MAP_SHARED) != 0)) {
1611 		if (!mls_dominate_effective(obj, subj))
1612 			return (EACCES);
1613 	}
1614 
1615 	return (0);
1616 }
1617 
1618 static int
1619 mls_posixshm_check_open(struct ucred *cred, struct shmfd *shmfd,
1620     struct label *shmlabel, accmode_t accmode)
1621 {
1622 	struct mac_mls *subj, *obj;
1623 
1624 	if (!mls_enabled)
1625 		return (0);
1626 
1627 	subj = SLOT(cred->cr_label);
1628 	obj = SLOT(shmlabel);
1629 
1630 	if (accmode & (VREAD | VEXEC | VSTAT_PERMS)) {
1631 		if (!mls_dominate_effective(subj, obj))
1632 			return (EACCES);
1633 	}
1634 	if (accmode & VMODIFY_PERMS) {
1635 		if (!mls_dominate_effective(obj, subj))
1636 			return (EACCES);
1637 	}
1638 
1639 	return (0);
1640 }
1641 
1642 static int
1643 mls_posixshm_check_read(struct ucred *active_cred, struct ucred *file_cred,
1644     struct shmfd *shm, struct label *shmlabel)
1645 {
1646 	struct mac_mls *subj, *obj;
1647 
1648 	if (!mls_enabled || !revocation_enabled)
1649 		return (0);
1650 
1651 	subj = SLOT(active_cred->cr_label);
1652 	obj = SLOT(shmlabel);
1653 
1654 	if (!mls_dominate_effective(subj, obj))
1655 		return (EACCES);
1656 
1657 	return (0);
1658 }
1659 
1660 static int
1661 mls_posixshm_check_setmode(struct ucred *cred, struct shmfd *shmfd,
1662     struct label *shmlabel, mode_t mode)
1663 {
1664 	struct mac_mls *subj, *obj;
1665 
1666 	if (!mls_enabled)
1667 		return (0);
1668 
1669 	subj = SLOT(cred->cr_label);
1670 	obj = SLOT(shmlabel);
1671 
1672 	if (!mls_dominate_effective(obj, subj))
1673 		return (EACCES);
1674 
1675 	return (0);
1676 }
1677 
1678 static int
1679 mls_posixshm_check_setowner(struct ucred *cred, struct shmfd *shmfd,
1680     struct label *shmlabel, uid_t uid, gid_t gid)
1681 {
1682 	struct mac_mls *subj, *obj;
1683 
1684 	if (!mls_enabled)
1685 		return (0);
1686 
1687 	subj = SLOT(cred->cr_label);
1688 	obj = SLOT(shmlabel);
1689 
1690 	if (!mls_dominate_effective(obj, subj))
1691 		return (EACCES);
1692 
1693 	return (0);
1694 }
1695 
1696 static int
1697 mls_posixshm_check_stat(struct ucred *active_cred, struct ucred *file_cred,
1698     struct shmfd *shmfd, struct label *shmlabel)
1699 {
1700 	struct mac_mls *subj, *obj;
1701 
1702 	if (!mls_enabled)
1703 		return (0);
1704 
1705 	subj = SLOT(active_cred->cr_label);
1706 	obj = SLOT(shmlabel);
1707 
1708 	if (!mls_dominate_effective(subj, obj))
1709 		return (EACCES);
1710 
1711 	return (0);
1712 }
1713 
1714 static int
1715 mls_posixshm_check_truncate(struct ucred *active_cred,
1716     struct ucred *file_cred, struct shmfd *shmfd, struct label *shmlabel)
1717 {
1718 	struct mac_mls *subj, *obj;
1719 
1720 	if (!mls_enabled)
1721 		return (0);
1722 
1723 	subj = SLOT(active_cred->cr_label);
1724 	obj = SLOT(shmlabel);
1725 
1726 	if (!mls_dominate_effective(obj, subj))
1727 		return (EACCES);
1728 
1729 	return (0);
1730 }
1731 
1732 static int
1733 mls_posixshm_check_unlink(struct ucred *cred, struct shmfd *shmfd,
1734     struct label *shmlabel)
1735 {
1736 	struct mac_mls *subj, *obj;
1737 
1738 	if (!mls_enabled)
1739 		return (0);
1740 
1741 	subj = SLOT(cred->cr_label);
1742 	obj = SLOT(shmlabel);
1743 
1744 	if (!mls_dominate_effective(obj, subj))
1745 		return (EACCES);
1746 
1747 	return (0);
1748 }
1749 
1750 static int
1751 mls_posixshm_check_write(struct ucred *active_cred, struct ucred *file_cred,
1752     struct shmfd *shm, struct label *shmlabel)
1753 {
1754 	struct mac_mls *subj, *obj;
1755 
1756 	if (!mls_enabled || !revocation_enabled)
1757 		return (0);
1758 
1759 	subj = SLOT(active_cred->cr_label);
1760 	obj = SLOT(shmlabel);
1761 
1762 	if (!mls_dominate_effective(subj, obj))
1763 		return (EACCES);
1764 
1765 	return (0);
1766 }
1767 
1768 static void
1769 mls_posixshm_create(struct ucred *cred, struct shmfd *shmfd,
1770     struct label *shmlabel)
1771 {
1772 	struct mac_mls *source, *dest;
1773 
1774 	source = SLOT(cred->cr_label);
1775 	dest = SLOT(shmlabel);
1776 
1777 	mls_copy_effective(source, dest);
1778 }
1779 
1780 static int
1781 mls_proc_check_debug(struct ucred *cred, struct proc *p)
1782 {
1783 	struct mac_mls *subj, *obj;
1784 
1785 	if (!mls_enabled)
1786 		return (0);
1787 
1788 	subj = SLOT(cred->cr_label);
1789 	obj = SLOT(p->p_ucred->cr_label);
1790 
1791 	/* XXX: range checks */
1792 	if (!mls_dominate_effective(subj, obj))
1793 		return (ESRCH);
1794 	if (!mls_dominate_effective(obj, subj))
1795 		return (EACCES);
1796 
1797 	return (0);
1798 }
1799 
1800 static int
1801 mls_proc_check_sched(struct ucred *cred, struct proc *p)
1802 {
1803 	struct mac_mls *subj, *obj;
1804 
1805 	if (!mls_enabled)
1806 		return (0);
1807 
1808 	subj = SLOT(cred->cr_label);
1809 	obj = SLOT(p->p_ucred->cr_label);
1810 
1811 	/* XXX: range checks */
1812 	if (!mls_dominate_effective(subj, obj))
1813 		return (ESRCH);
1814 	if (!mls_dominate_effective(obj, subj))
1815 		return (EACCES);
1816 
1817 	return (0);
1818 }
1819 
1820 static int
1821 mls_proc_check_signal(struct ucred *cred, struct proc *p, int signum)
1822 {
1823 	struct mac_mls *subj, *obj;
1824 
1825 	if (!mls_enabled)
1826 		return (0);
1827 
1828 	subj = SLOT(cred->cr_label);
1829 	obj = SLOT(p->p_ucred->cr_label);
1830 
1831 	/* XXX: range checks */
1832 	if (!mls_dominate_effective(subj, obj))
1833 		return (ESRCH);
1834 	if (!mls_dominate_effective(obj, subj))
1835 		return (EACCES);
1836 
1837 	return (0);
1838 }
1839 
1840 static int
1841 mls_socket_check_deliver(struct socket *so, struct label *solabel,
1842     struct mbuf *m, struct label *mlabel)
1843 {
1844 	struct mac_mls *p, *s;
1845 	int error;
1846 
1847 	if (!mls_enabled)
1848 		return (0);
1849 
1850 	p = SLOT(mlabel);
1851 	s = SLOT(solabel);
1852 
1853 	SOCK_LOCK(so);
1854 	error = mls_equal_effective(p, s) ? 0 : EACCES;
1855 	SOCK_UNLOCK(so);
1856 
1857 	return (error);
1858 }
1859 
1860 static int
1861 mls_socket_check_relabel(struct ucred *cred, struct socket *so,
1862     struct label *solabel, struct label *newlabel)
1863 {
1864 	struct mac_mls *subj, *obj, *new;
1865 	int error;
1866 
1867 	SOCK_LOCK_ASSERT(so);
1868 
1869 	new = SLOT(newlabel);
1870 	subj = SLOT(cred->cr_label);
1871 	obj = SLOT(solabel);
1872 
1873 	/*
1874 	 * If there is an MLS label update for the socket, it may be an
1875 	 * update of effective.
1876 	 */
1877 	error = mls_atmostflags(new, MAC_MLS_FLAG_EFFECTIVE);
1878 	if (error)
1879 		return (error);
1880 
1881 	/*
1882 	 * To relabel a socket, the old socket effective must be in the
1883 	 * subject range.
1884 	 */
1885 	if (!mls_effective_in_range(obj, subj))
1886 		return (EPERM);
1887 
1888 	/*
1889 	 * If the MLS label is to be changed, authorize as appropriate.
1890 	 */
1891 	if (new->mm_flags & MAC_MLS_FLAG_EFFECTIVE) {
1892 		/*
1893 		 * To relabel a socket, the new socket effective must be in
1894 		 * the subject range.
1895 		 */
1896 		if (!mls_effective_in_range(new, subj))
1897 			return (EPERM);
1898 
1899 		/*
1900 		 * To change the MLS label on the socket to contain EQUAL,
1901 		 * the subject must have appropriate privilege.
1902 		 */
1903 		if (mls_contains_equal(new)) {
1904 			error = mls_subject_privileged(subj);
1905 			if (error)
1906 				return (error);
1907 		}
1908 	}
1909 
1910 	return (0);
1911 }
1912 
1913 static int
1914 mls_socket_check_visible(struct ucred *cred, struct socket *so,
1915     struct label *solabel)
1916 {
1917 	struct mac_mls *subj, *obj;
1918 
1919 	if (!mls_enabled)
1920 		return (0);
1921 
1922 	subj = SLOT(cred->cr_label);
1923 	obj = SLOT(solabel);
1924 
1925 	SOCK_LOCK(so);
1926 	if (!mls_dominate_effective(subj, obj)) {
1927 		SOCK_UNLOCK(so);
1928 		return (ENOENT);
1929 	}
1930 	SOCK_UNLOCK(so);
1931 
1932 	return (0);
1933 }
1934 
1935 static void
1936 mls_socket_create(struct ucred *cred, struct socket *so,
1937     struct label *solabel)
1938 {
1939 	struct mac_mls *source, *dest;
1940 
1941 	source = SLOT(cred->cr_label);
1942 	dest = SLOT(solabel);
1943 
1944 	mls_copy_effective(source, dest);
1945 }
1946 
1947 static void
1948 mls_socket_create_mbuf(struct socket *so, struct label *solabel,
1949     struct mbuf *m, struct label *mlabel)
1950 {
1951 	struct mac_mls *source, *dest;
1952 
1953 	source = SLOT(solabel);
1954 	dest = SLOT(mlabel);
1955 
1956 	SOCK_LOCK(so);
1957 	mls_copy_effective(source, dest);
1958 	SOCK_UNLOCK(so);
1959 }
1960 
1961 static void
1962 mls_socket_newconn(struct socket *oldso, struct label *oldsolabel,
1963     struct socket *newso, struct label *newsolabel)
1964 {
1965 	struct mac_mls source, *dest;
1966 
1967 	SOCK_LOCK(oldso);
1968 	source = *SLOT(oldsolabel);
1969 	SOCK_UNLOCK(oldso);
1970 
1971 	dest = SLOT(newsolabel);
1972 
1973 	SOCK_LOCK(newso);
1974 	mls_copy_effective(&source, dest);
1975 	SOCK_UNLOCK(newso);
1976 }
1977 
1978 static void
1979 mls_socket_relabel(struct ucred *cred, struct socket *so,
1980     struct label *solabel, struct label *newlabel)
1981 {
1982 	struct mac_mls *source, *dest;
1983 
1984 	SOCK_LOCK_ASSERT(so);
1985 
1986 	source = SLOT(newlabel);
1987 	dest = SLOT(solabel);
1988 
1989 	mls_copy(source, dest);
1990 }
1991 
1992 static void
1993 mls_socketpeer_set_from_mbuf(struct mbuf *m, struct label *mlabel,
1994     struct socket *so, struct label *sopeerlabel)
1995 {
1996 	struct mac_mls *source, *dest;
1997 
1998 	source = SLOT(mlabel);
1999 	dest = SLOT(sopeerlabel);
2000 
2001 	SOCK_LOCK(so);
2002 	mls_copy_effective(source, dest);
2003 	SOCK_UNLOCK(so);
2004 }
2005 
2006 static void
2007 mls_socketpeer_set_from_socket(struct socket *oldso,
2008     struct label *oldsolabel, struct socket *newso,
2009     struct label *newsopeerlabel)
2010 {
2011 	struct mac_mls source, *dest;
2012 
2013 	SOCK_LOCK(oldso);
2014 	source = *SLOT(oldsolabel);
2015 	SOCK_UNLOCK(oldso);
2016 
2017 	dest = SLOT(newsopeerlabel);
2018 
2019 	SOCK_LOCK(newso);
2020 	mls_copy_effective(&source, dest);
2021 	SOCK_UNLOCK(newso);
2022 }
2023 
2024 static void
2025 mls_syncache_create(struct label *label, struct inpcb *inp)
2026 {
2027 	struct mac_mls *source, *dest;
2028 
2029 	source = SLOT(inp->inp_label);
2030 	dest = SLOT(label);
2031 
2032 	mls_copy_effective(source, dest);
2033 }
2034 
2035 static void
2036 mls_syncache_create_mbuf(struct label *sc_label, struct mbuf *m,
2037     struct label *mlabel)
2038 {
2039 	struct mac_mls *source, *dest;
2040 
2041 	source = SLOT(sc_label);
2042 	dest = SLOT(mlabel);
2043 
2044 	mls_copy_effective(source, dest);
2045 }
2046 
2047 static int
2048 mls_system_check_acct(struct ucred *cred, struct vnode *vp,
2049     struct label *vplabel)
2050 {
2051 	struct mac_mls *subj, *obj;
2052 
2053 	if (!mls_enabled)
2054 		return (0);
2055 
2056 	if (vplabel == NULL)
2057 		return (0);
2058 
2059 	subj = SLOT(cred->cr_label);
2060 	obj = SLOT(vplabel);
2061 
2062 	if (!mls_dominate_effective(obj, subj) ||
2063 	    !mls_dominate_effective(subj, obj))
2064 		return (EACCES);
2065 
2066 	return (0);
2067 }
2068 
2069 static int
2070 mls_system_check_auditctl(struct ucred *cred, struct vnode *vp,
2071     struct label *vplabel)
2072 {
2073 	struct mac_mls *subj, *obj;
2074 
2075 	if (!mls_enabled)
2076 		return (0);
2077 
2078 	subj = SLOT(cred->cr_label);
2079 	obj = SLOT(vplabel);
2080 
2081 	if (!mls_dominate_effective(obj, subj) ||
2082 	    !mls_dominate_effective(subj, obj))
2083 		return (EACCES);
2084 
2085 	return (0);
2086 }
2087 
2088 static int
2089 mls_system_check_swapon(struct ucred *cred, struct vnode *vp,
2090     struct label *vplabel)
2091 {
2092 	struct mac_mls *subj, *obj;
2093 
2094 	if (!mls_enabled)
2095 		return (0);
2096 
2097 	subj = SLOT(cred->cr_label);
2098 	obj = SLOT(vplabel);
2099 
2100 	if (!mls_dominate_effective(obj, subj) ||
2101 	    !mls_dominate_effective(subj, obj))
2102 		return (EACCES);
2103 
2104 	return (0);
2105 }
2106 
2107 static void
2108 mls_sysvmsg_cleanup(struct label *msglabel)
2109 {
2110 
2111 	bzero(SLOT(msglabel), sizeof(struct mac_mls));
2112 }
2113 
2114 static void
2115 mls_sysvmsg_create(struct ucred *cred, struct msqid_kernel *msqkptr,
2116     struct label *msqlabel, struct msg *msgptr, struct label *msglabel)
2117 {
2118 	struct mac_mls *source, *dest;
2119 
2120 	/* Ignore the msgq label. */
2121 	source = SLOT(cred->cr_label);
2122 	dest = SLOT(msglabel);
2123 
2124 	mls_copy_effective(source, dest);
2125 }
2126 
2127 static int
2128 mls_sysvmsq_check_msgrcv(struct ucred *cred, struct msg *msgptr,
2129     struct label *msglabel)
2130 {
2131 	struct mac_mls *subj, *obj;
2132 
2133 	if (!mls_enabled)
2134 		return (0);
2135 
2136 	subj = SLOT(cred->cr_label);
2137 	obj = SLOT(msglabel);
2138 
2139 	if (!mls_dominate_effective(subj, obj))
2140 		return (EACCES);
2141 
2142 	return (0);
2143 }
2144 
2145 static int
2146 mls_sysvmsq_check_msgrmid(struct ucred *cred, struct msg *msgptr,
2147     struct label *msglabel)
2148 {
2149 	struct mac_mls *subj, *obj;
2150 
2151 	if (!mls_enabled)
2152 		return (0);
2153 
2154 	subj = SLOT(cred->cr_label);
2155 	obj = SLOT(msglabel);
2156 
2157 	if (!mls_dominate_effective(obj, subj))
2158 		return (EACCES);
2159 
2160 	return (0);
2161 }
2162 
2163 static int
2164 mls_sysvmsq_check_msqget(struct ucred *cred, struct msqid_kernel *msqkptr,
2165     struct label *msqklabel)
2166 {
2167 	struct mac_mls *subj, *obj;
2168 
2169 	if (!mls_enabled)
2170 		return (0);
2171 
2172 	subj = SLOT(cred->cr_label);
2173 	obj = SLOT(msqklabel);
2174 
2175 	if (!mls_dominate_effective(subj, obj))
2176 		return (EACCES);
2177 
2178 	return (0);
2179 }
2180 
2181 static int
2182 mls_sysvmsq_check_msqsnd(struct ucred *cred, struct msqid_kernel *msqkptr,
2183     struct label *msqklabel)
2184 {
2185 	struct mac_mls *subj, *obj;
2186 
2187 	if (!mls_enabled)
2188 		return (0);
2189 
2190 	subj = SLOT(cred->cr_label);
2191 	obj = SLOT(msqklabel);
2192 
2193 	if (!mls_dominate_effective(obj, subj))
2194 		return (EACCES);
2195 
2196 	return (0);
2197 }
2198 
2199 static int
2200 mls_sysvmsq_check_msqrcv(struct ucred *cred, struct msqid_kernel *msqkptr,
2201     struct label *msqklabel)
2202 {
2203 	struct mac_mls *subj, *obj;
2204 
2205 	if (!mls_enabled)
2206 		return (0);
2207 
2208 	subj = SLOT(cred->cr_label);
2209 	obj = SLOT(msqklabel);
2210 
2211 	if (!mls_dominate_effective(subj, obj))
2212 		return (EACCES);
2213 
2214 	return (0);
2215 }
2216 
2217 static int
2218 mls_sysvmsq_check_msqctl(struct ucred *cred, struct msqid_kernel *msqkptr,
2219     struct label *msqklabel, int cmd)
2220 {
2221 	struct mac_mls *subj, *obj;
2222 
2223 	if (!mls_enabled)
2224 		return (0);
2225 
2226 	subj = SLOT(cred->cr_label);
2227 	obj = SLOT(msqklabel);
2228 
2229 	switch(cmd) {
2230 	case IPC_RMID:
2231 	case IPC_SET:
2232 		if (!mls_dominate_effective(obj, subj))
2233 			return (EACCES);
2234 		break;
2235 
2236 	case IPC_STAT:
2237 		if (!mls_dominate_effective(subj, obj))
2238 			return (EACCES);
2239 		break;
2240 
2241 	default:
2242 		return (EACCES);
2243 	}
2244 
2245 	return (0);
2246 }
2247 
2248 static void
2249 mls_sysvmsq_cleanup(struct label *msqlabel)
2250 {
2251 
2252 	bzero(SLOT(msqlabel), sizeof(struct mac_mls));
2253 }
2254 
2255 static void
2256 mls_sysvmsq_create(struct ucred *cred, struct msqid_kernel *msqkptr,
2257     struct label *msqlabel)
2258 {
2259 	struct mac_mls *source, *dest;
2260 
2261 	source = SLOT(cred->cr_label);
2262 	dest = SLOT(msqlabel);
2263 
2264 	mls_copy_effective(source, dest);
2265 }
2266 
2267 static int
2268 mls_sysvsem_check_semctl(struct ucred *cred, struct semid_kernel *semakptr,
2269     struct label *semaklabel, int cmd)
2270 {
2271 	struct mac_mls *subj, *obj;
2272 
2273 	if (!mls_enabled)
2274 		return (0);
2275 
2276 	subj = SLOT(cred->cr_label);
2277 	obj = SLOT(semaklabel);
2278 
2279 	switch(cmd) {
2280 	case IPC_RMID:
2281 	case IPC_SET:
2282 	case SETVAL:
2283 	case SETALL:
2284 		if (!mls_dominate_effective(obj, subj))
2285 			return (EACCES);
2286 		break;
2287 
2288 	case IPC_STAT:
2289 	case GETVAL:
2290 	case GETPID:
2291 	case GETNCNT:
2292 	case GETZCNT:
2293 	case GETALL:
2294 		if (!mls_dominate_effective(subj, obj))
2295 			return (EACCES);
2296 		break;
2297 
2298 	default:
2299 		return (EACCES);
2300 	}
2301 
2302 	return (0);
2303 }
2304 
2305 static int
2306 mls_sysvsem_check_semget(struct ucred *cred, struct semid_kernel *semakptr,
2307     struct label *semaklabel)
2308 {
2309 	struct mac_mls *subj, *obj;
2310 
2311 	if (!mls_enabled)
2312 		return (0);
2313 
2314 	subj = SLOT(cred->cr_label);
2315 	obj = SLOT(semaklabel);
2316 
2317 	if (!mls_dominate_effective(subj, obj))
2318 		return (EACCES);
2319 
2320 	return (0);
2321 }
2322 
2323 static int
2324 mls_sysvsem_check_semop(struct ucred *cred, struct semid_kernel *semakptr,
2325     struct label *semaklabel, size_t accesstype)
2326 {
2327 	struct mac_mls *subj, *obj;
2328 
2329 	if (!mls_enabled)
2330 		return (0);
2331 
2332 	subj = SLOT(cred->cr_label);
2333 	obj = SLOT(semaklabel);
2334 
2335 	if( accesstype & SEM_R )
2336 		if (!mls_dominate_effective(subj, obj))
2337 			return (EACCES);
2338 
2339 	if( accesstype & SEM_A )
2340 		if (!mls_dominate_effective(obj, subj))
2341 			return (EACCES);
2342 
2343 	return (0);
2344 }
2345 
2346 static void
2347 mls_sysvsem_cleanup(struct label *semalabel)
2348 {
2349 
2350 	bzero(SLOT(semalabel), sizeof(struct mac_mls));
2351 }
2352 
2353 static void
2354 mls_sysvsem_create(struct ucred *cred, struct semid_kernel *semakptr,
2355     struct label *semalabel)
2356 {
2357 	struct mac_mls *source, *dest;
2358 
2359 	source = SLOT(cred->cr_label);
2360 	dest = SLOT(semalabel);
2361 
2362 	mls_copy_effective(source, dest);
2363 }
2364 
2365 static int
2366 mls_sysvshm_check_shmat(struct ucred *cred, struct shmid_kernel *shmsegptr,
2367     struct label *shmseglabel, int shmflg)
2368 {
2369 	struct mac_mls *subj, *obj;
2370 
2371 	if (!mls_enabled)
2372 		return (0);
2373 
2374 	subj = SLOT(cred->cr_label);
2375 	obj = SLOT(shmseglabel);
2376 
2377 	if (!mls_dominate_effective(subj, obj))
2378 		return (EACCES);
2379 	if ((shmflg & SHM_RDONLY) == 0) {
2380 		if (!mls_dominate_effective(obj, subj))
2381 			return (EACCES);
2382 	}
2383 
2384 	return (0);
2385 }
2386 
2387 static int
2388 mls_sysvshm_check_shmctl(struct ucred *cred, struct shmid_kernel *shmsegptr,
2389     struct label *shmseglabel, int cmd)
2390 {
2391 	struct mac_mls *subj, *obj;
2392 
2393 	if (!mls_enabled)
2394 		return (0);
2395 
2396 	subj = SLOT(cred->cr_label);
2397 	obj = SLOT(shmseglabel);
2398 
2399 	switch(cmd) {
2400 	case IPC_RMID:
2401 	case IPC_SET:
2402 		if (!mls_dominate_effective(obj, subj))
2403 			return (EACCES);
2404 		break;
2405 
2406 	case IPC_STAT:
2407 	case SHM_STAT:
2408 		if (!mls_dominate_effective(subj, obj))
2409 			return (EACCES);
2410 		break;
2411 
2412 	default:
2413 		return (EACCES);
2414 	}
2415 
2416 	return (0);
2417 }
2418 
2419 static int
2420 mls_sysvshm_check_shmget(struct ucred *cred, struct shmid_kernel *shmsegptr,
2421     struct label *shmseglabel, int shmflg)
2422 {
2423 	struct mac_mls *subj, *obj;
2424 
2425 	if (!mls_enabled)
2426 		return (0);
2427 
2428 	subj = SLOT(cred->cr_label);
2429 	obj = SLOT(shmseglabel);
2430 
2431 	if (!mls_dominate_effective(obj, subj))
2432 		return (EACCES);
2433 
2434 	return (0);
2435 }
2436 
2437 static void
2438 mls_sysvshm_cleanup(struct label *shmlabel)
2439 {
2440 
2441 	bzero(SLOT(shmlabel), sizeof(struct mac_mls));
2442 }
2443 
2444 static void
2445 mls_sysvshm_create(struct ucred *cred, struct shmid_kernel *shmsegptr,
2446     struct label *shmlabel)
2447 {
2448 	struct mac_mls *source, *dest;
2449 
2450 	source = SLOT(cred->cr_label);
2451 	dest = SLOT(shmlabel);
2452 
2453 	mls_copy_effective(source, dest);
2454 }
2455 
2456 static int
2457 mls_vnode_associate_extattr(struct mount *mp, struct label *mplabel,
2458     struct vnode *vp, struct label *vplabel)
2459 {
2460 	struct mac_mls mm_temp, *source, *dest;
2461 	int buflen, error;
2462 
2463 	source = SLOT(mplabel);
2464 	dest = SLOT(vplabel);
2465 
2466 	buflen = sizeof(mm_temp);
2467 	bzero(&mm_temp, buflen);
2468 
2469 	error = vn_extattr_get(vp, IO_NODELOCKED, MAC_MLS_EXTATTR_NAMESPACE,
2470 	    MAC_MLS_EXTATTR_NAME, &buflen, (char *) &mm_temp, curthread);
2471 	if (error == ENOATTR || error == EOPNOTSUPP) {
2472 		/* Fall back to the mntlabel. */
2473 		mls_copy_effective(source, dest);
2474 		return (0);
2475 	} else if (error)
2476 		return (error);
2477 
2478 	if (buflen != sizeof(mm_temp)) {
2479 		printf("mls_vnode_associate_extattr: bad size %d\n", buflen);
2480 		return (EPERM);
2481 	}
2482 	if (mls_valid(&mm_temp) != 0) {
2483 		printf("mls_vnode_associate_extattr: invalid\n");
2484 		return (EPERM);
2485 	}
2486 	if ((mm_temp.mm_flags & MAC_MLS_FLAGS_BOTH) !=
2487 	    MAC_MLS_FLAG_EFFECTIVE) {
2488 		printf("mls_associated_vnode_extattr: not effective\n");
2489 		return (EPERM);
2490 	}
2491 
2492 	mls_copy_effective(&mm_temp, dest);
2493 	return (0);
2494 }
2495 
2496 static void
2497 mls_vnode_associate_singlelabel(struct mount *mp, struct label *mplabel,
2498     struct vnode *vp, struct label *vplabel)
2499 {
2500 	struct mac_mls *source, *dest;
2501 
2502 	source = SLOT(mplabel);
2503 	dest = SLOT(vplabel);
2504 
2505 	mls_copy_effective(source, dest);
2506 }
2507 
2508 static int
2509 mls_vnode_check_chdir(struct ucred *cred, struct vnode *dvp,
2510     struct label *dvplabel)
2511 {
2512 	struct mac_mls *subj, *obj;
2513 
2514 	if (!mls_enabled)
2515 		return (0);
2516 
2517 	subj = SLOT(cred->cr_label);
2518 	obj = SLOT(dvplabel);
2519 
2520 	if (!mls_dominate_effective(subj, obj))
2521 		return (EACCES);
2522 
2523 	return (0);
2524 }
2525 
2526 static int
2527 mls_vnode_check_chroot(struct ucred *cred, struct vnode *dvp,
2528     struct label *dvplabel)
2529 {
2530 	struct mac_mls *subj, *obj;
2531 
2532 	if (!mls_enabled)
2533 		return (0);
2534 
2535 	subj = SLOT(cred->cr_label);
2536 	obj = SLOT(dvplabel);
2537 
2538 	if (!mls_dominate_effective(subj, obj))
2539 		return (EACCES);
2540 
2541 	return (0);
2542 }
2543 
2544 static int
2545 mls_vnode_check_create(struct ucred *cred, struct vnode *dvp,
2546     struct label *dvplabel, struct componentname *cnp, struct vattr *vap)
2547 {
2548 	struct mac_mls *subj, *obj;
2549 
2550 	if (!mls_enabled)
2551 		return (0);
2552 
2553 	subj = SLOT(cred->cr_label);
2554 	obj = SLOT(dvplabel);
2555 
2556 	if (!mls_dominate_effective(obj, subj))
2557 		return (EACCES);
2558 
2559 	return (0);
2560 }
2561 
2562 static int
2563 mls_vnode_check_deleteacl(struct ucred *cred, struct vnode *vp,
2564     struct label *vplabel, acl_type_t type)
2565 {
2566 	struct mac_mls *subj, *obj;
2567 
2568 	if (!mls_enabled)
2569 		return (0);
2570 
2571 	subj = SLOT(cred->cr_label);
2572 	obj = SLOT(vplabel);
2573 
2574 	if (!mls_dominate_effective(obj, subj))
2575 		return (EACCES);
2576 
2577 	return (0);
2578 }
2579 
2580 static int
2581 mls_vnode_check_deleteextattr(struct ucred *cred, struct vnode *vp,
2582     struct label *vplabel, int attrnamespace, const char *name)
2583 {
2584 	struct mac_mls *subj, *obj;
2585 
2586 	if (!mls_enabled)
2587 		return (0);
2588 
2589 	subj = SLOT(cred->cr_label);
2590 	obj = SLOT(vplabel);
2591 
2592 	if (!mls_dominate_effective(obj, subj))
2593 		return (EACCES);
2594 
2595 	return (0);
2596 }
2597 
2598 static int
2599 mls_vnode_check_exec(struct ucred *cred, struct vnode *vp,
2600     struct label *vplabel, struct image_params *imgp,
2601     struct label *execlabel)
2602 {
2603 	struct mac_mls *subj, *obj, *exec;
2604 	int error;
2605 
2606 	if (execlabel != NULL) {
2607 		/*
2608 		 * We currently don't permit labels to be changed at
2609 		 * exec-time as part of MLS, so disallow non-NULL MLS label
2610 		 * elements in the execlabel.
2611 		 */
2612 		exec = SLOT(execlabel);
2613 		error = mls_atmostflags(exec, 0);
2614 		if (error)
2615 			return (error);
2616 	}
2617 
2618 	if (!mls_enabled)
2619 		return (0);
2620 
2621 	subj = SLOT(cred->cr_label);
2622 	obj = SLOT(vplabel);
2623 
2624 	if (!mls_dominate_effective(subj, obj))
2625 		return (EACCES);
2626 
2627 	return (0);
2628 }
2629 
2630 static int
2631 mls_vnode_check_getacl(struct ucred *cred, struct vnode *vp,
2632     struct label *vplabel, acl_type_t type)
2633 {
2634 	struct mac_mls *subj, *obj;
2635 
2636 	if (!mls_enabled)
2637 		return (0);
2638 
2639 	subj = SLOT(cred->cr_label);
2640 	obj = SLOT(vplabel);
2641 
2642 	if (!mls_dominate_effective(subj, obj))
2643 		return (EACCES);
2644 
2645 	return (0);
2646 }
2647 
2648 static int
2649 mls_vnode_check_getextattr(struct ucred *cred, struct vnode *vp,
2650     struct label *vplabel, int attrnamespace, const char *name)
2651 {
2652 	struct mac_mls *subj, *obj;
2653 
2654 	if (!mls_enabled)
2655 		return (0);
2656 
2657 	subj = SLOT(cred->cr_label);
2658 	obj = SLOT(vplabel);
2659 
2660 	if (!mls_dominate_effective(subj, obj))
2661 		return (EACCES);
2662 
2663 	return (0);
2664 }
2665 
2666 static int
2667 mls_vnode_check_link(struct ucred *cred, struct vnode *dvp,
2668     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2669     struct componentname *cnp)
2670 {
2671 	struct mac_mls *subj, *obj;
2672 
2673 	if (!mls_enabled)
2674 		return (0);
2675 
2676 	subj = SLOT(cred->cr_label);
2677 	obj = SLOT(dvplabel);
2678 
2679 	if (!mls_dominate_effective(obj, subj))
2680 		return (EACCES);
2681 
2682 	obj = SLOT(vplabel);
2683 	if (!mls_dominate_effective(obj, subj))
2684 		return (EACCES);
2685 
2686 	return (0);
2687 }
2688 
2689 static int
2690 mls_vnode_check_listextattr(struct ucred *cred, struct vnode *vp,
2691     struct label *vplabel, int attrnamespace)
2692 {
2693 
2694 	struct mac_mls *subj, *obj;
2695 
2696 	if (!mls_enabled)
2697 		return (0);
2698 
2699 	subj = SLOT(cred->cr_label);
2700 	obj = SLOT(vplabel);
2701 
2702 	if (!mls_dominate_effective(subj, obj))
2703 		return (EACCES);
2704 
2705 	return (0);
2706 }
2707 
2708 static int
2709 mls_vnode_check_lookup(struct ucred *cred, struct vnode *dvp,
2710     struct label *dvplabel, struct componentname *cnp)
2711 {
2712 	struct mac_mls *subj, *obj;
2713 
2714 	if (!mls_enabled)
2715 		return (0);
2716 
2717 	subj = SLOT(cred->cr_label);
2718 	obj = SLOT(dvplabel);
2719 
2720 	if (!mls_dominate_effective(subj, obj))
2721 		return (EACCES);
2722 
2723 	return (0);
2724 }
2725 
2726 static int
2727 mls_vnode_check_mmap(struct ucred *cred, struct vnode *vp,
2728     struct label *vplabel, int prot, int flags)
2729 {
2730 	struct mac_mls *subj, *obj;
2731 
2732 	/*
2733 	 * Rely on the use of open()-time protections to handle
2734 	 * non-revocation cases.
2735 	 */
2736 	if (!mls_enabled || !revocation_enabled)
2737 		return (0);
2738 
2739 	subj = SLOT(cred->cr_label);
2740 	obj = SLOT(vplabel);
2741 
2742 	if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
2743 		if (!mls_dominate_effective(subj, obj))
2744 			return (EACCES);
2745 	}
2746 	if (((prot & VM_PROT_WRITE) != 0) && ((flags & MAP_SHARED) != 0)) {
2747 		if (!mls_dominate_effective(obj, subj))
2748 			return (EACCES);
2749 	}
2750 
2751 	return (0);
2752 }
2753 
2754 static int
2755 mls_vnode_check_open(struct ucred *cred, struct vnode *vp,
2756     struct label *vplabel, accmode_t accmode)
2757 {
2758 	struct mac_mls *subj, *obj;
2759 
2760 	if (!mls_enabled)
2761 		return (0);
2762 
2763 	subj = SLOT(cred->cr_label);
2764 	obj = SLOT(vplabel);
2765 
2766 	/* XXX privilege override for admin? */
2767 	if (accmode & (VREAD | VEXEC | VSTAT_PERMS)) {
2768 		if (!mls_dominate_effective(subj, obj))
2769 			return (EACCES);
2770 	}
2771 	if (accmode & VMODIFY_PERMS) {
2772 		if (!mls_dominate_effective(obj, subj))
2773 			return (EACCES);
2774 	}
2775 
2776 	return (0);
2777 }
2778 
2779 static int
2780 mls_vnode_check_poll(struct ucred *active_cred, struct ucred *file_cred,
2781     struct vnode *vp, struct label *vplabel)
2782 {
2783 	struct mac_mls *subj, *obj;
2784 
2785 	if (!mls_enabled || !revocation_enabled)
2786 		return (0);
2787 
2788 	subj = SLOT(active_cred->cr_label);
2789 	obj = SLOT(vplabel);
2790 
2791 	if (!mls_dominate_effective(subj, obj))
2792 		return (EACCES);
2793 
2794 	return (0);
2795 }
2796 
2797 static int
2798 mls_vnode_check_read(struct ucred *active_cred, struct ucred *file_cred,
2799     struct vnode *vp, struct label *vplabel)
2800 {
2801 	struct mac_mls *subj, *obj;
2802 
2803 	if (!mls_enabled || !revocation_enabled)
2804 		return (0);
2805 
2806 	subj = SLOT(active_cred->cr_label);
2807 	obj = SLOT(vplabel);
2808 
2809 	if (!mls_dominate_effective(subj, obj))
2810 		return (EACCES);
2811 
2812 	return (0);
2813 }
2814 
2815 static int
2816 mls_vnode_check_readdir(struct ucred *cred, struct vnode *dvp,
2817     struct label *dvplabel)
2818 {
2819 	struct mac_mls *subj, *obj;
2820 
2821 	if (!mls_enabled)
2822 		return (0);
2823 
2824 	subj = SLOT(cred->cr_label);
2825 	obj = SLOT(dvplabel);
2826 
2827 	if (!mls_dominate_effective(subj, obj))
2828 		return (EACCES);
2829 
2830 	return (0);
2831 }
2832 
2833 static int
2834 mls_vnode_check_readlink(struct ucred *cred, struct vnode *vp,
2835     struct label *vplabel)
2836 {
2837 	struct mac_mls *subj, *obj;
2838 
2839 	if (!mls_enabled)
2840 		return (0);
2841 
2842 	subj = SLOT(cred->cr_label);
2843 	obj = SLOT(vplabel);
2844 
2845 	if (!mls_dominate_effective(subj, obj))
2846 		return (EACCES);
2847 
2848 	return (0);
2849 }
2850 
2851 static int
2852 mls_vnode_check_relabel(struct ucred *cred, struct vnode *vp,
2853     struct label *vplabel, struct label *newlabel)
2854 {
2855 	struct mac_mls *old, *new, *subj;
2856 	int error;
2857 
2858 	old = SLOT(vplabel);
2859 	new = SLOT(newlabel);
2860 	subj = SLOT(cred->cr_label);
2861 
2862 	/*
2863 	 * If there is an MLS label update for the vnode, it must be a
2864 	 * effective label.
2865 	 */
2866 	error = mls_atmostflags(new, MAC_MLS_FLAG_EFFECTIVE);
2867 	if (error)
2868 		return (error);
2869 
2870 	/*
2871 	 * To perform a relabel of the vnode (MLS label or not), MLS must
2872 	 * authorize the relabel.
2873 	 */
2874 	if (!mls_effective_in_range(old, subj))
2875 		return (EPERM);
2876 
2877 	/*
2878 	 * If the MLS label is to be changed, authorize as appropriate.
2879 	 */
2880 	if (new->mm_flags & MAC_MLS_FLAG_EFFECTIVE) {
2881 		/*
2882 		 * To change the MLS label on a vnode, the new vnode label
2883 		 * must be in the subject range.
2884 		 */
2885 		if (!mls_effective_in_range(new, subj))
2886 			return (EPERM);
2887 
2888 		/*
2889 		 * To change the MLS label on the vnode to be EQUAL, the
2890 		 * subject must have appropriate privilege.
2891 		 */
2892 		if (mls_contains_equal(new)) {
2893 			error = mls_subject_privileged(subj);
2894 			if (error)
2895 				return (error);
2896 		}
2897 	}
2898 
2899 	return (0);
2900 }
2901 
2902 static int
2903 mls_vnode_check_rename_from(struct ucred *cred, struct vnode *dvp,
2904     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2905     struct componentname *cnp)
2906 {
2907 	struct mac_mls *subj, *obj;
2908 
2909 	if (!mls_enabled)
2910 		return (0);
2911 
2912 	subj = SLOT(cred->cr_label);
2913 	obj = SLOT(dvplabel);
2914 
2915 	if (!mls_dominate_effective(obj, subj))
2916 		return (EACCES);
2917 
2918 	obj = SLOT(vplabel);
2919 
2920 	if (!mls_dominate_effective(obj, subj))
2921 		return (EACCES);
2922 
2923 	return (0);
2924 }
2925 
2926 static int
2927 mls_vnode_check_rename_to(struct ucred *cred, struct vnode *dvp,
2928     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
2929     int samedir, struct componentname *cnp)
2930 {
2931 	struct mac_mls *subj, *obj;
2932 
2933 	if (!mls_enabled)
2934 		return (0);
2935 
2936 	subj = SLOT(cred->cr_label);
2937 	obj = SLOT(dvplabel);
2938 
2939 	if (!mls_dominate_effective(obj, subj))
2940 		return (EACCES);
2941 
2942 	if (vp != NULL) {
2943 		obj = SLOT(vplabel);
2944 
2945 		if (!mls_dominate_effective(obj, subj))
2946 			return (EACCES);
2947 	}
2948 
2949 	return (0);
2950 }
2951 
2952 static int
2953 mls_vnode_check_revoke(struct ucred *cred, struct vnode *vp,
2954     struct label *vplabel)
2955 {
2956 	struct mac_mls *subj, *obj;
2957 
2958 	if (!mls_enabled)
2959 		return (0);
2960 
2961 	subj = SLOT(cred->cr_label);
2962 	obj = SLOT(vplabel);
2963 
2964 	if (!mls_dominate_effective(obj, subj))
2965 		return (EACCES);
2966 
2967 	return (0);
2968 }
2969 
2970 static int
2971 mls_vnode_check_setacl(struct ucred *cred, struct vnode *vp,
2972     struct label *vplabel, acl_type_t type, struct acl *acl)
2973 {
2974 	struct mac_mls *subj, *obj;
2975 
2976 	if (!mls_enabled)
2977 		return (0);
2978 
2979 	subj = SLOT(cred->cr_label);
2980 	obj = SLOT(vplabel);
2981 
2982 	if (!mls_dominate_effective(obj, subj))
2983 		return (EACCES);
2984 
2985 	return (0);
2986 }
2987 
2988 static int
2989 mls_vnode_check_setextattr(struct ucred *cred, struct vnode *vp,
2990     struct label *vplabel, int attrnamespace, const char *name)
2991 {
2992 	struct mac_mls *subj, *obj;
2993 
2994 	if (!mls_enabled)
2995 		return (0);
2996 
2997 	subj = SLOT(cred->cr_label);
2998 	obj = SLOT(vplabel);
2999 
3000 	if (!mls_dominate_effective(obj, subj))
3001 		return (EACCES);
3002 
3003 	/* XXX: protect the MAC EA in a special way? */
3004 
3005 	return (0);
3006 }
3007 
3008 static int
3009 mls_vnode_check_setflags(struct ucred *cred, struct vnode *vp,
3010     struct label *vplabel, u_long flags)
3011 {
3012 	struct mac_mls *subj, *obj;
3013 
3014 	if (!mls_enabled)
3015 		return (0);
3016 
3017 	subj = SLOT(cred->cr_label);
3018 	obj = SLOT(vplabel);
3019 
3020 	if (!mls_dominate_effective(obj, subj))
3021 		return (EACCES);
3022 
3023 	return (0);
3024 }
3025 
3026 static int
3027 mls_vnode_check_setmode(struct ucred *cred, struct vnode *vp,
3028     struct label *vplabel, mode_t mode)
3029 {
3030 	struct mac_mls *subj, *obj;
3031 
3032 	if (!mls_enabled)
3033 		return (0);
3034 
3035 	subj = SLOT(cred->cr_label);
3036 	obj = SLOT(vplabel);
3037 
3038 	if (!mls_dominate_effective(obj, subj))
3039 		return (EACCES);
3040 
3041 	return (0);
3042 }
3043 
3044 static int
3045 mls_vnode_check_setowner(struct ucred *cred, struct vnode *vp,
3046     struct label *vplabel, uid_t uid, gid_t gid)
3047 {
3048 	struct mac_mls *subj, *obj;
3049 
3050 	if (!mls_enabled)
3051 		return (0);
3052 
3053 	subj = SLOT(cred->cr_label);
3054 	obj = SLOT(vplabel);
3055 
3056 	if (!mls_dominate_effective(obj, subj))
3057 		return (EACCES);
3058 
3059 	return (0);
3060 }
3061 
3062 static int
3063 mls_vnode_check_setutimes(struct ucred *cred, struct vnode *vp,
3064     struct label *vplabel, struct timespec atime, struct timespec mtime)
3065 {
3066 	struct mac_mls *subj, *obj;
3067 
3068 	if (!mls_enabled)
3069 		return (0);
3070 
3071 	subj = SLOT(cred->cr_label);
3072 	obj = SLOT(vplabel);
3073 
3074 	if (!mls_dominate_effective(obj, subj))
3075 		return (EACCES);
3076 
3077 	return (0);
3078 }
3079 
3080 static int
3081 mls_vnode_check_stat(struct ucred *active_cred, struct ucred *file_cred,
3082     struct vnode *vp, struct label *vplabel)
3083 {
3084 	struct mac_mls *subj, *obj;
3085 
3086 	if (!mls_enabled)
3087 		return (0);
3088 
3089 	subj = SLOT(active_cred->cr_label);
3090 	obj = SLOT(vplabel);
3091 
3092 	if (!mls_dominate_effective(subj, obj))
3093 		return (EACCES);
3094 
3095 	return (0);
3096 }
3097 
3098 static int
3099 mls_vnode_check_unlink(struct ucred *cred, struct vnode *dvp,
3100     struct label *dvplabel, struct vnode *vp, struct label *vplabel,
3101     struct componentname *cnp)
3102 {
3103 	struct mac_mls *subj, *obj;
3104 
3105 	if (!mls_enabled)
3106 		return (0);
3107 
3108 	subj = SLOT(cred->cr_label);
3109 	obj = SLOT(dvplabel);
3110 
3111 	if (!mls_dominate_effective(obj, subj))
3112 		return (EACCES);
3113 
3114 	obj = SLOT(vplabel);
3115 
3116 	if (!mls_dominate_effective(obj, subj))
3117 		return (EACCES);
3118 
3119 	return (0);
3120 }
3121 
3122 static int
3123 mls_vnode_check_write(struct ucred *active_cred, struct ucred *file_cred,
3124     struct vnode *vp, struct label *vplabel)
3125 {
3126 	struct mac_mls *subj, *obj;
3127 
3128 	if (!mls_enabled || !revocation_enabled)
3129 		return (0);
3130 
3131 	subj = SLOT(active_cred->cr_label);
3132 	obj = SLOT(vplabel);
3133 
3134 	if (!mls_dominate_effective(obj, subj))
3135 		return (EACCES);
3136 
3137 	return (0);
3138 }
3139 
3140 static int
3141 mls_vnode_create_extattr(struct ucred *cred, struct mount *mp,
3142     struct label *mplabel, struct vnode *dvp, struct label *dvplabel,
3143     struct vnode *vp, struct label *vplabel, struct componentname *cnp)
3144 {
3145 	struct mac_mls *source, *dest, mm_temp;
3146 	size_t buflen;
3147 	int error;
3148 
3149 	buflen = sizeof(mm_temp);
3150 	bzero(&mm_temp, buflen);
3151 
3152 	source = SLOT(cred->cr_label);
3153 	dest = SLOT(vplabel);
3154 	mls_copy_effective(source, &mm_temp);
3155 
3156 	error = vn_extattr_set(vp, IO_NODELOCKED, MAC_MLS_EXTATTR_NAMESPACE,
3157 	    MAC_MLS_EXTATTR_NAME, buflen, (char *) &mm_temp, curthread);
3158 	if (error == 0)
3159 		mls_copy_effective(source, dest);
3160 	return (error);
3161 }
3162 
3163 static void
3164 mls_vnode_relabel(struct ucred *cred, struct vnode *vp,
3165     struct label *vplabel, struct label *label)
3166 {
3167 	struct mac_mls *source, *dest;
3168 
3169 	source = SLOT(label);
3170 	dest = SLOT(vplabel);
3171 
3172 	mls_copy(source, dest);
3173 }
3174 
3175 static int
3176 mls_vnode_setlabel_extattr(struct ucred *cred, struct vnode *vp,
3177     struct label *vplabel, struct label *intlabel)
3178 {
3179 	struct mac_mls *source, mm_temp;
3180 	size_t buflen;
3181 	int error;
3182 
3183 	buflen = sizeof(mm_temp);
3184 	bzero(&mm_temp, buflen);
3185 
3186 	source = SLOT(intlabel);
3187 	if ((source->mm_flags & MAC_MLS_FLAG_EFFECTIVE) == 0)
3188 		return (0);
3189 
3190 	mls_copy_effective(source, &mm_temp);
3191 
3192 	error = vn_extattr_set(vp, IO_NODELOCKED, MAC_MLS_EXTATTR_NAMESPACE,
3193 	    MAC_MLS_EXTATTR_NAME, buflen, (char *) &mm_temp, curthread);
3194 	return (error);
3195 }
3196 
3197 static struct mac_policy_ops mls_ops =
3198 {
3199 	.mpo_init = mls_init,
3200 
3201 	.mpo_bpfdesc_check_receive = mls_bpfdesc_check_receive,
3202 	.mpo_bpfdesc_create = mls_bpfdesc_create,
3203 	.mpo_bpfdesc_create_mbuf = mls_bpfdesc_create_mbuf,
3204 	.mpo_bpfdesc_destroy_label = mls_destroy_label,
3205 	.mpo_bpfdesc_init_label = mls_init_label,
3206 
3207 	.mpo_cred_associate_nfsd = mls_cred_associate_nfsd,
3208 	.mpo_cred_check_relabel = mls_cred_check_relabel,
3209 	.mpo_cred_check_visible = mls_cred_check_visible,
3210 	.mpo_cred_copy_label = mls_copy_label,
3211 	.mpo_cred_create_init = mls_cred_create_init,
3212 	.mpo_cred_create_swapper = mls_cred_create_swapper,
3213 	.mpo_cred_destroy_label = mls_destroy_label,
3214 	.mpo_cred_externalize_label = mls_externalize_label,
3215 	.mpo_cred_init_label = mls_init_label,
3216 	.mpo_cred_internalize_label = mls_internalize_label,
3217 	.mpo_cred_relabel = mls_cred_relabel,
3218 
3219 	.mpo_devfs_create_device = mls_devfs_create_device,
3220 	.mpo_devfs_create_directory = mls_devfs_create_directory,
3221 	.mpo_devfs_create_symlink = mls_devfs_create_symlink,
3222 	.mpo_devfs_destroy_label = mls_destroy_label,
3223 	.mpo_devfs_init_label = mls_init_label,
3224 	.mpo_devfs_update = mls_devfs_update,
3225 	.mpo_devfs_vnode_associate = mls_devfs_vnode_associate,
3226 
3227 	.mpo_ifnet_check_relabel = mls_ifnet_check_relabel,
3228 	.mpo_ifnet_check_transmit = mls_ifnet_check_transmit,
3229 	.mpo_ifnet_copy_label = mls_copy_label,
3230 	.mpo_ifnet_create = mls_ifnet_create,
3231 	.mpo_ifnet_create_mbuf = mls_ifnet_create_mbuf,
3232 	.mpo_ifnet_destroy_label = mls_destroy_label,
3233 	.mpo_ifnet_externalize_label = mls_externalize_label,
3234 	.mpo_ifnet_init_label = mls_init_label,
3235 	.mpo_ifnet_internalize_label = mls_internalize_label,
3236 	.mpo_ifnet_relabel = mls_ifnet_relabel,
3237 
3238 	.mpo_inpcb_check_deliver = mls_inpcb_check_deliver,
3239 	.mpo_inpcb_check_visible = mls_inpcb_check_visible,
3240 	.mpo_inpcb_create = mls_inpcb_create,
3241 	.mpo_inpcb_create_mbuf = mls_inpcb_create_mbuf,
3242 	.mpo_inpcb_destroy_label = mls_destroy_label,
3243 	.mpo_inpcb_init_label = mls_init_label_waitcheck,
3244 	.mpo_inpcb_sosetlabel = mls_inpcb_sosetlabel,
3245 
3246 	.mpo_ip6q_create = mls_ip6q_create,
3247 	.mpo_ip6q_destroy_label = mls_destroy_label,
3248 	.mpo_ip6q_init_label = mls_init_label_waitcheck,
3249 	.mpo_ip6q_match = mls_ip6q_match,
3250 	.mpo_ip6q_reassemble = mls_ip6q_reassemble,
3251 	.mpo_ip6q_update = mls_ip6q_update,
3252 
3253 	.mpo_ipq_create = mls_ipq_create,
3254 	.mpo_ipq_destroy_label = mls_destroy_label,
3255 	.mpo_ipq_init_label = mls_init_label_waitcheck,
3256 	.mpo_ipq_match = mls_ipq_match,
3257 	.mpo_ipq_reassemble = mls_ipq_reassemble,
3258 	.mpo_ipq_update = mls_ipq_update,
3259 
3260 	.mpo_mbuf_copy_label = mls_copy_label,
3261 	.mpo_mbuf_destroy_label = mls_destroy_label,
3262 	.mpo_mbuf_init_label = mls_init_label_waitcheck,
3263 
3264 	.mpo_mount_check_stat = mls_mount_check_stat,
3265 	.mpo_mount_create = mls_mount_create,
3266 	.mpo_mount_destroy_label = mls_destroy_label,
3267 	.mpo_mount_init_label = mls_init_label,
3268 
3269 	.mpo_netinet_arp_send = mls_netinet_arp_send,
3270 	.mpo_netinet_firewall_reply = mls_netinet_firewall_reply,
3271 	.mpo_netinet_firewall_send = mls_netinet_firewall_send,
3272 	.mpo_netinet_fragment = mls_netinet_fragment,
3273 	.mpo_netinet_icmp_reply = mls_netinet_icmp_reply,
3274 	.mpo_netinet_igmp_send = mls_netinet_igmp_send,
3275 
3276 	.mpo_netinet6_nd6_send = mls_netinet6_nd6_send,
3277 
3278 	.mpo_pipe_check_ioctl = mls_pipe_check_ioctl,
3279 	.mpo_pipe_check_poll = mls_pipe_check_poll,
3280 	.mpo_pipe_check_read = mls_pipe_check_read,
3281 	.mpo_pipe_check_relabel = mls_pipe_check_relabel,
3282 	.mpo_pipe_check_stat = mls_pipe_check_stat,
3283 	.mpo_pipe_check_write = mls_pipe_check_write,
3284 	.mpo_pipe_copy_label = mls_copy_label,
3285 	.mpo_pipe_create = mls_pipe_create,
3286 	.mpo_pipe_destroy_label = mls_destroy_label,
3287 	.mpo_pipe_externalize_label = mls_externalize_label,
3288 	.mpo_pipe_init_label = mls_init_label,
3289 	.mpo_pipe_internalize_label = mls_internalize_label,
3290 	.mpo_pipe_relabel = mls_pipe_relabel,
3291 
3292 	.mpo_posixsem_check_getvalue = mls_posixsem_check_rdonly,
3293 	.mpo_posixsem_check_open = mls_posixsem_check_openunlink,
3294 	.mpo_posixsem_check_post = mls_posixsem_check_write,
3295 	.mpo_posixsem_check_setmode = mls_posixsem_check_setmode,
3296 	.mpo_posixsem_check_setowner = mls_posixsem_check_setowner,
3297 	.mpo_posixsem_check_stat = mls_posixsem_check_rdonly,
3298 	.mpo_posixsem_check_unlink = mls_posixsem_check_openunlink,
3299 	.mpo_posixsem_check_wait = mls_posixsem_check_write,
3300 	.mpo_posixsem_create = mls_posixsem_create,
3301 	.mpo_posixsem_destroy_label = mls_destroy_label,
3302 	.mpo_posixsem_init_label = mls_init_label,
3303 
3304 	.mpo_posixshm_check_mmap = mls_posixshm_check_mmap,
3305 	.mpo_posixshm_check_open = mls_posixshm_check_open,
3306 	.mpo_posixshm_check_read = mls_posixshm_check_read,
3307 	.mpo_posixshm_check_setmode = mls_posixshm_check_setmode,
3308 	.mpo_posixshm_check_setowner = mls_posixshm_check_setowner,
3309 	.mpo_posixshm_check_stat = mls_posixshm_check_stat,
3310 	.mpo_posixshm_check_truncate = mls_posixshm_check_truncate,
3311 	.mpo_posixshm_check_unlink = mls_posixshm_check_unlink,
3312 	.mpo_posixshm_check_write = mls_posixshm_check_write,
3313 	.mpo_posixshm_create = mls_posixshm_create,
3314 	.mpo_posixshm_destroy_label = mls_destroy_label,
3315 	.mpo_posixshm_init_label = mls_init_label,
3316 
3317 	.mpo_proc_check_debug = mls_proc_check_debug,
3318 	.mpo_proc_check_sched = mls_proc_check_sched,
3319 	.mpo_proc_check_signal = mls_proc_check_signal,
3320 
3321 	.mpo_socket_check_deliver = mls_socket_check_deliver,
3322 	.mpo_socket_check_relabel = mls_socket_check_relabel,
3323 	.mpo_socket_check_visible = mls_socket_check_visible,
3324 	.mpo_socket_copy_label = mls_copy_label,
3325 	.mpo_socket_create = mls_socket_create,
3326 	.mpo_socket_create_mbuf = mls_socket_create_mbuf,
3327 	.mpo_socket_destroy_label = mls_destroy_label,
3328 	.mpo_socket_externalize_label = mls_externalize_label,
3329 	.mpo_socket_init_label = mls_init_label_waitcheck,
3330 	.mpo_socket_internalize_label = mls_internalize_label,
3331 	.mpo_socket_newconn = mls_socket_newconn,
3332 	.mpo_socket_relabel = mls_socket_relabel,
3333 
3334 	.mpo_socketpeer_destroy_label = mls_destroy_label,
3335 	.mpo_socketpeer_externalize_label = mls_externalize_label,
3336 	.mpo_socketpeer_init_label = mls_init_label_waitcheck,
3337 	.mpo_socketpeer_set_from_mbuf = mls_socketpeer_set_from_mbuf,
3338 	.mpo_socketpeer_set_from_socket = mls_socketpeer_set_from_socket,
3339 
3340 	.mpo_syncache_create = mls_syncache_create,
3341 	.mpo_syncache_create_mbuf = mls_syncache_create_mbuf,
3342 	.mpo_syncache_destroy_label = mls_destroy_label,
3343 	.mpo_syncache_init_label = mls_init_label_waitcheck,
3344 
3345 	.mpo_sysvmsg_cleanup = mls_sysvmsg_cleanup,
3346 	.mpo_sysvmsg_create = mls_sysvmsg_create,
3347 	.mpo_sysvmsg_destroy_label = mls_destroy_label,
3348 	.mpo_sysvmsg_init_label = mls_init_label,
3349 
3350 	.mpo_sysvmsq_check_msgrcv = mls_sysvmsq_check_msgrcv,
3351 	.mpo_sysvmsq_check_msgrmid = mls_sysvmsq_check_msgrmid,
3352 	.mpo_sysvmsq_check_msqget = mls_sysvmsq_check_msqget,
3353 	.mpo_sysvmsq_check_msqsnd = mls_sysvmsq_check_msqsnd,
3354 	.mpo_sysvmsq_check_msqrcv = mls_sysvmsq_check_msqrcv,
3355 	.mpo_sysvmsq_check_msqctl = mls_sysvmsq_check_msqctl,
3356 	.mpo_sysvmsq_cleanup = mls_sysvmsq_cleanup,
3357 	.mpo_sysvmsq_destroy_label = mls_destroy_label,
3358 	.mpo_sysvmsq_init_label = mls_init_label,
3359 	.mpo_sysvmsq_create = mls_sysvmsq_create,
3360 
3361 	.mpo_sysvsem_check_semctl = mls_sysvsem_check_semctl,
3362 	.mpo_sysvsem_check_semget = mls_sysvsem_check_semget,
3363 	.mpo_sysvsem_check_semop = mls_sysvsem_check_semop,
3364 	.mpo_sysvsem_cleanup = mls_sysvsem_cleanup,
3365 	.mpo_sysvsem_create = mls_sysvsem_create,
3366 	.mpo_sysvsem_destroy_label = mls_destroy_label,
3367 	.mpo_sysvsem_init_label = mls_init_label,
3368 
3369 	.mpo_sysvshm_check_shmat = mls_sysvshm_check_shmat,
3370 	.mpo_sysvshm_check_shmctl = mls_sysvshm_check_shmctl,
3371 	.mpo_sysvshm_check_shmget = mls_sysvshm_check_shmget,
3372 	.mpo_sysvshm_cleanup = mls_sysvshm_cleanup,
3373 	.mpo_sysvshm_create = mls_sysvshm_create,
3374 	.mpo_sysvshm_destroy_label = mls_destroy_label,
3375 	.mpo_sysvshm_init_label = mls_init_label,
3376 
3377 
3378 	.mpo_system_check_acct = mls_system_check_acct,
3379 	.mpo_system_check_auditctl = mls_system_check_auditctl,
3380 	.mpo_system_check_swapon = mls_system_check_swapon,
3381 
3382 	.mpo_vnode_associate_extattr = mls_vnode_associate_extattr,
3383 	.mpo_vnode_associate_singlelabel = mls_vnode_associate_singlelabel,
3384 	.mpo_vnode_check_access = mls_vnode_check_open,
3385 	.mpo_vnode_check_chdir = mls_vnode_check_chdir,
3386 	.mpo_vnode_check_chroot = mls_vnode_check_chroot,
3387 	.mpo_vnode_check_create = mls_vnode_check_create,
3388 	.mpo_vnode_check_deleteacl = mls_vnode_check_deleteacl,
3389 	.mpo_vnode_check_deleteextattr = mls_vnode_check_deleteextattr,
3390 	.mpo_vnode_check_exec = mls_vnode_check_exec,
3391 	.mpo_vnode_check_getacl = mls_vnode_check_getacl,
3392 	.mpo_vnode_check_getextattr = mls_vnode_check_getextattr,
3393 	.mpo_vnode_check_link = mls_vnode_check_link,
3394 	.mpo_vnode_check_listextattr = mls_vnode_check_listextattr,
3395 	.mpo_vnode_check_lookup = mls_vnode_check_lookup,
3396 	.mpo_vnode_check_mmap = mls_vnode_check_mmap,
3397 	.mpo_vnode_check_open = mls_vnode_check_open,
3398 	.mpo_vnode_check_poll = mls_vnode_check_poll,
3399 	.mpo_vnode_check_read = mls_vnode_check_read,
3400 	.mpo_vnode_check_readdir = mls_vnode_check_readdir,
3401 	.mpo_vnode_check_readlink = mls_vnode_check_readlink,
3402 	.mpo_vnode_check_relabel = mls_vnode_check_relabel,
3403 	.mpo_vnode_check_rename_from = mls_vnode_check_rename_from,
3404 	.mpo_vnode_check_rename_to = mls_vnode_check_rename_to,
3405 	.mpo_vnode_check_revoke = mls_vnode_check_revoke,
3406 	.mpo_vnode_check_setacl = mls_vnode_check_setacl,
3407 	.mpo_vnode_check_setextattr = mls_vnode_check_setextattr,
3408 	.mpo_vnode_check_setflags = mls_vnode_check_setflags,
3409 	.mpo_vnode_check_setmode = mls_vnode_check_setmode,
3410 	.mpo_vnode_check_setowner = mls_vnode_check_setowner,
3411 	.mpo_vnode_check_setutimes = mls_vnode_check_setutimes,
3412 	.mpo_vnode_check_stat = mls_vnode_check_stat,
3413 	.mpo_vnode_check_unlink = mls_vnode_check_unlink,
3414 	.mpo_vnode_check_write = mls_vnode_check_write,
3415 	.mpo_vnode_copy_label = mls_copy_label,
3416 	.mpo_vnode_create_extattr = mls_vnode_create_extattr,
3417 	.mpo_vnode_destroy_label = mls_destroy_label,
3418 	.mpo_vnode_externalize_label = mls_externalize_label,
3419 	.mpo_vnode_init_label = mls_init_label,
3420 	.mpo_vnode_internalize_label = mls_internalize_label,
3421 	.mpo_vnode_relabel = mls_vnode_relabel,
3422 	.mpo_vnode_setlabel_extattr = mls_vnode_setlabel_extattr,
3423 };
3424 
3425 MAC_POLICY_SET(&mls_ops, mac_mls, "TrustedBSD MAC/MLS",
3426     MPC_LOADTIME_FLAG_NOTLATE, &mls_slot);
3427