xref: /openbmc/linux/security/selinux/ss/services.c (revision a44d924c)
1 /*
2  * Implementation of the security services.
3  *
4  * Authors : Stephen Smalley, <sds@tycho.nsa.gov>
5  *	     James Morris <jmorris@redhat.com>
6  *
7  * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
8  *
9  *	Support for enhanced MLS infrastructure.
10  *	Support for context based audit filters.
11  *
12  * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
13  *
14  *	Added conditional policy language extensions
15  *
16  * Updated: Hewlett-Packard <paul@paul-moore.com>
17  *
18  *      Added support for NetLabel
19  *      Added support for the policy capability bitmap
20  *
21  * Updated: Chad Sellers <csellers@tresys.com>
22  *
23  *  Added validation of kernel classes and permissions
24  *
25  * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
26  *
27  *  Added support for bounds domain and audit messaged on masked permissions
28  *
29  * Updated: Guido Trentalancia <guido@trentalancia.com>
30  *
31  *  Added support for runtime switching of the policy type
32  *
33  * Copyright (C) 2008, 2009 NEC Corporation
34  * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
35  * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
36  * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
37  * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
38  *	This program is free software; you can redistribute it and/or modify
39  *	it under the terms of the GNU General Public License as published by
40  *	the Free Software Foundation, version 2.
41  */
42 #include <linux/kernel.h>
43 #include <linux/slab.h>
44 #include <linux/string.h>
45 #include <linux/spinlock.h>
46 #include <linux/rcupdate.h>
47 #include <linux/errno.h>
48 #include <linux/in.h>
49 #include <linux/sched.h>
50 #include <linux/audit.h>
51 #include <linux/mutex.h>
52 #include <linux/selinux.h>
53 #include <linux/flex_array.h>
54 #include <linux/vmalloc.h>
55 #include <net/netlabel.h>
56 
57 #include "flask.h"
58 #include "avc.h"
59 #include "avc_ss.h"
60 #include "security.h"
61 #include "context.h"
62 #include "policydb.h"
63 #include "sidtab.h"
64 #include "services.h"
65 #include "conditional.h"
66 #include "mls.h"
67 #include "objsec.h"
68 #include "netlabel.h"
69 #include "xfrm.h"
70 #include "ebitmap.h"
71 #include "audit.h"
72 
73 /* Policy capability names */
74 const char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = {
75 	"network_peer_controls",
76 	"open_perms",
77 	"extended_socket_class",
78 	"always_check_network",
79 	"cgroup_seclabel",
80 	"nnp_nosuid_transition"
81 };
82 
83 static struct selinux_ss selinux_ss;
84 
85 void selinux_ss_init(struct selinux_ss **ss)
86 {
87 	rwlock_init(&selinux_ss.policy_rwlock);
88 	mutex_init(&selinux_ss.status_lock);
89 	*ss = &selinux_ss;
90 }
91 
92 /* Forward declaration. */
93 static int context_struct_to_string(struct policydb *policydb,
94 				    struct context *context,
95 				    char **scontext,
96 				    u32 *scontext_len);
97 
98 static void context_struct_compute_av(struct policydb *policydb,
99 				      struct context *scontext,
100 				      struct context *tcontext,
101 				      u16 tclass,
102 				      struct av_decision *avd,
103 				      struct extended_perms *xperms);
104 
105 static int selinux_set_mapping(struct policydb *pol,
106 			       struct security_class_mapping *map,
107 			       struct selinux_map *out_map)
108 {
109 	u16 i, j;
110 	unsigned k;
111 	bool print_unknown_handle = false;
112 
113 	/* Find number of classes in the input mapping */
114 	if (!map)
115 		return -EINVAL;
116 	i = 0;
117 	while (map[i].name)
118 		i++;
119 
120 	/* Allocate space for the class records, plus one for class zero */
121 	out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC);
122 	if (!out_map->mapping)
123 		return -ENOMEM;
124 
125 	/* Store the raw class and permission values */
126 	j = 0;
127 	while (map[j].name) {
128 		struct security_class_mapping *p_in = map + (j++);
129 		struct selinux_mapping *p_out = out_map->mapping + j;
130 
131 		/* An empty class string skips ahead */
132 		if (!strcmp(p_in->name, "")) {
133 			p_out->num_perms = 0;
134 			continue;
135 		}
136 
137 		p_out->value = string_to_security_class(pol, p_in->name);
138 		if (!p_out->value) {
139 			pr_info("SELinux:  Class %s not defined in policy.\n",
140 			       p_in->name);
141 			if (pol->reject_unknown)
142 				goto err;
143 			p_out->num_perms = 0;
144 			print_unknown_handle = true;
145 			continue;
146 		}
147 
148 		k = 0;
149 		while (p_in->perms[k]) {
150 			/* An empty permission string skips ahead */
151 			if (!*p_in->perms[k]) {
152 				k++;
153 				continue;
154 			}
155 			p_out->perms[k] = string_to_av_perm(pol, p_out->value,
156 							    p_in->perms[k]);
157 			if (!p_out->perms[k]) {
158 				pr_info("SELinux:  Permission %s in class %s not defined in policy.\n",
159 				       p_in->perms[k], p_in->name);
160 				if (pol->reject_unknown)
161 					goto err;
162 				print_unknown_handle = true;
163 			}
164 
165 			k++;
166 		}
167 		p_out->num_perms = k;
168 	}
169 
170 	if (print_unknown_handle)
171 		pr_info("SELinux: the above unknown classes and permissions will be %s\n",
172 		       pol->allow_unknown ? "allowed" : "denied");
173 
174 	out_map->size = i;
175 	return 0;
176 err:
177 	kfree(out_map->mapping);
178 	out_map->mapping = NULL;
179 	return -EINVAL;
180 }
181 
182 /*
183  * Get real, policy values from mapped values
184  */
185 
186 static u16 unmap_class(struct selinux_map *map, u16 tclass)
187 {
188 	if (tclass < map->size)
189 		return map->mapping[tclass].value;
190 
191 	return tclass;
192 }
193 
194 /*
195  * Get kernel value for class from its policy value
196  */
197 static u16 map_class(struct selinux_map *map, u16 pol_value)
198 {
199 	u16 i;
200 
201 	for (i = 1; i < map->size; i++) {
202 		if (map->mapping[i].value == pol_value)
203 			return i;
204 	}
205 
206 	return SECCLASS_NULL;
207 }
208 
209 static void map_decision(struct selinux_map *map,
210 			 u16 tclass, struct av_decision *avd,
211 			 int allow_unknown)
212 {
213 	if (tclass < map->size) {
214 		struct selinux_mapping *mapping = &map->mapping[tclass];
215 		unsigned int i, n = mapping->num_perms;
216 		u32 result;
217 
218 		for (i = 0, result = 0; i < n; i++) {
219 			if (avd->allowed & mapping->perms[i])
220 				result |= 1<<i;
221 			if (allow_unknown && !mapping->perms[i])
222 				result |= 1<<i;
223 		}
224 		avd->allowed = result;
225 
226 		for (i = 0, result = 0; i < n; i++)
227 			if (avd->auditallow & mapping->perms[i])
228 				result |= 1<<i;
229 		avd->auditallow = result;
230 
231 		for (i = 0, result = 0; i < n; i++) {
232 			if (avd->auditdeny & mapping->perms[i])
233 				result |= 1<<i;
234 			if (!allow_unknown && !mapping->perms[i])
235 				result |= 1<<i;
236 		}
237 		/*
238 		 * In case the kernel has a bug and requests a permission
239 		 * between num_perms and the maximum permission number, we
240 		 * should audit that denial
241 		 */
242 		for (; i < (sizeof(u32)*8); i++)
243 			result |= 1<<i;
244 		avd->auditdeny = result;
245 	}
246 }
247 
248 int security_mls_enabled(struct selinux_state *state)
249 {
250 	struct policydb *p = &state->ss->policydb;
251 
252 	return p->mls_enabled;
253 }
254 
255 /*
256  * Return the boolean value of a constraint expression
257  * when it is applied to the specified source and target
258  * security contexts.
259  *
260  * xcontext is a special beast...  It is used by the validatetrans rules
261  * only.  For these rules, scontext is the context before the transition,
262  * tcontext is the context after the transition, and xcontext is the context
263  * of the process performing the transition.  All other callers of
264  * constraint_expr_eval should pass in NULL for xcontext.
265  */
266 static int constraint_expr_eval(struct policydb *policydb,
267 				struct context *scontext,
268 				struct context *tcontext,
269 				struct context *xcontext,
270 				struct constraint_expr *cexpr)
271 {
272 	u32 val1, val2;
273 	struct context *c;
274 	struct role_datum *r1, *r2;
275 	struct mls_level *l1, *l2;
276 	struct constraint_expr *e;
277 	int s[CEXPR_MAXDEPTH];
278 	int sp = -1;
279 
280 	for (e = cexpr; e; e = e->next) {
281 		switch (e->expr_type) {
282 		case CEXPR_NOT:
283 			BUG_ON(sp < 0);
284 			s[sp] = !s[sp];
285 			break;
286 		case CEXPR_AND:
287 			BUG_ON(sp < 1);
288 			sp--;
289 			s[sp] &= s[sp + 1];
290 			break;
291 		case CEXPR_OR:
292 			BUG_ON(sp < 1);
293 			sp--;
294 			s[sp] |= s[sp + 1];
295 			break;
296 		case CEXPR_ATTR:
297 			if (sp == (CEXPR_MAXDEPTH - 1))
298 				return 0;
299 			switch (e->attr) {
300 			case CEXPR_USER:
301 				val1 = scontext->user;
302 				val2 = tcontext->user;
303 				break;
304 			case CEXPR_TYPE:
305 				val1 = scontext->type;
306 				val2 = tcontext->type;
307 				break;
308 			case CEXPR_ROLE:
309 				val1 = scontext->role;
310 				val2 = tcontext->role;
311 				r1 = policydb->role_val_to_struct[val1 - 1];
312 				r2 = policydb->role_val_to_struct[val2 - 1];
313 				switch (e->op) {
314 				case CEXPR_DOM:
315 					s[++sp] = ebitmap_get_bit(&r1->dominates,
316 								  val2 - 1);
317 					continue;
318 				case CEXPR_DOMBY:
319 					s[++sp] = ebitmap_get_bit(&r2->dominates,
320 								  val1 - 1);
321 					continue;
322 				case CEXPR_INCOMP:
323 					s[++sp] = (!ebitmap_get_bit(&r1->dominates,
324 								    val2 - 1) &&
325 						   !ebitmap_get_bit(&r2->dominates,
326 								    val1 - 1));
327 					continue;
328 				default:
329 					break;
330 				}
331 				break;
332 			case CEXPR_L1L2:
333 				l1 = &(scontext->range.level[0]);
334 				l2 = &(tcontext->range.level[0]);
335 				goto mls_ops;
336 			case CEXPR_L1H2:
337 				l1 = &(scontext->range.level[0]);
338 				l2 = &(tcontext->range.level[1]);
339 				goto mls_ops;
340 			case CEXPR_H1L2:
341 				l1 = &(scontext->range.level[1]);
342 				l2 = &(tcontext->range.level[0]);
343 				goto mls_ops;
344 			case CEXPR_H1H2:
345 				l1 = &(scontext->range.level[1]);
346 				l2 = &(tcontext->range.level[1]);
347 				goto mls_ops;
348 			case CEXPR_L1H1:
349 				l1 = &(scontext->range.level[0]);
350 				l2 = &(scontext->range.level[1]);
351 				goto mls_ops;
352 			case CEXPR_L2H2:
353 				l1 = &(tcontext->range.level[0]);
354 				l2 = &(tcontext->range.level[1]);
355 				goto mls_ops;
356 mls_ops:
357 			switch (e->op) {
358 			case CEXPR_EQ:
359 				s[++sp] = mls_level_eq(l1, l2);
360 				continue;
361 			case CEXPR_NEQ:
362 				s[++sp] = !mls_level_eq(l1, l2);
363 				continue;
364 			case CEXPR_DOM:
365 				s[++sp] = mls_level_dom(l1, l2);
366 				continue;
367 			case CEXPR_DOMBY:
368 				s[++sp] = mls_level_dom(l2, l1);
369 				continue;
370 			case CEXPR_INCOMP:
371 				s[++sp] = mls_level_incomp(l2, l1);
372 				continue;
373 			default:
374 				BUG();
375 				return 0;
376 			}
377 			break;
378 			default:
379 				BUG();
380 				return 0;
381 			}
382 
383 			switch (e->op) {
384 			case CEXPR_EQ:
385 				s[++sp] = (val1 == val2);
386 				break;
387 			case CEXPR_NEQ:
388 				s[++sp] = (val1 != val2);
389 				break;
390 			default:
391 				BUG();
392 				return 0;
393 			}
394 			break;
395 		case CEXPR_NAMES:
396 			if (sp == (CEXPR_MAXDEPTH-1))
397 				return 0;
398 			c = scontext;
399 			if (e->attr & CEXPR_TARGET)
400 				c = tcontext;
401 			else if (e->attr & CEXPR_XTARGET) {
402 				c = xcontext;
403 				if (!c) {
404 					BUG();
405 					return 0;
406 				}
407 			}
408 			if (e->attr & CEXPR_USER)
409 				val1 = c->user;
410 			else if (e->attr & CEXPR_ROLE)
411 				val1 = c->role;
412 			else if (e->attr & CEXPR_TYPE)
413 				val1 = c->type;
414 			else {
415 				BUG();
416 				return 0;
417 			}
418 
419 			switch (e->op) {
420 			case CEXPR_EQ:
421 				s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
422 				break;
423 			case CEXPR_NEQ:
424 				s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
425 				break;
426 			default:
427 				BUG();
428 				return 0;
429 			}
430 			break;
431 		default:
432 			BUG();
433 			return 0;
434 		}
435 	}
436 
437 	BUG_ON(sp != 0);
438 	return s[0];
439 }
440 
441 /*
442  * security_dump_masked_av - dumps masked permissions during
443  * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
444  */
445 static int dump_masked_av_helper(void *k, void *d, void *args)
446 {
447 	struct perm_datum *pdatum = d;
448 	char **permission_names = args;
449 
450 	BUG_ON(pdatum->value < 1 || pdatum->value > 32);
451 
452 	permission_names[pdatum->value - 1] = (char *)k;
453 
454 	return 0;
455 }
456 
457 static void security_dump_masked_av(struct policydb *policydb,
458 				    struct context *scontext,
459 				    struct context *tcontext,
460 				    u16 tclass,
461 				    u32 permissions,
462 				    const char *reason)
463 {
464 	struct common_datum *common_dat;
465 	struct class_datum *tclass_dat;
466 	struct audit_buffer *ab;
467 	char *tclass_name;
468 	char *scontext_name = NULL;
469 	char *tcontext_name = NULL;
470 	char *permission_names[32];
471 	int index;
472 	u32 length;
473 	bool need_comma = false;
474 
475 	if (!permissions)
476 		return;
477 
478 	tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1);
479 	tclass_dat = policydb->class_val_to_struct[tclass - 1];
480 	common_dat = tclass_dat->comdatum;
481 
482 	/* init permission_names */
483 	if (common_dat &&
484 	    hashtab_map(common_dat->permissions.table,
485 			dump_masked_av_helper, permission_names) < 0)
486 		goto out;
487 
488 	if (hashtab_map(tclass_dat->permissions.table,
489 			dump_masked_av_helper, permission_names) < 0)
490 		goto out;
491 
492 	/* get scontext/tcontext in text form */
493 	if (context_struct_to_string(policydb, scontext,
494 				     &scontext_name, &length) < 0)
495 		goto out;
496 
497 	if (context_struct_to_string(policydb, tcontext,
498 				     &tcontext_name, &length) < 0)
499 		goto out;
500 
501 	/* audit a message */
502 	ab = audit_log_start(audit_context(),
503 			     GFP_ATOMIC, AUDIT_SELINUX_ERR);
504 	if (!ab)
505 		goto out;
506 
507 	audit_log_format(ab, "op=security_compute_av reason=%s "
508 			 "scontext=%s tcontext=%s tclass=%s perms=",
509 			 reason, scontext_name, tcontext_name, tclass_name);
510 
511 	for (index = 0; index < 32; index++) {
512 		u32 mask = (1 << index);
513 
514 		if ((mask & permissions) == 0)
515 			continue;
516 
517 		audit_log_format(ab, "%s%s",
518 				 need_comma ? "," : "",
519 				 permission_names[index]
520 				 ? permission_names[index] : "????");
521 		need_comma = true;
522 	}
523 	audit_log_end(ab);
524 out:
525 	/* release scontext/tcontext */
526 	kfree(tcontext_name);
527 	kfree(scontext_name);
528 
529 	return;
530 }
531 
532 /*
533  * security_boundary_permission - drops violated permissions
534  * on boundary constraint.
535  */
536 static void type_attribute_bounds_av(struct policydb *policydb,
537 				     struct context *scontext,
538 				     struct context *tcontext,
539 				     u16 tclass,
540 				     struct av_decision *avd)
541 {
542 	struct context lo_scontext;
543 	struct context lo_tcontext, *tcontextp = tcontext;
544 	struct av_decision lo_avd;
545 	struct type_datum *source;
546 	struct type_datum *target;
547 	u32 masked = 0;
548 
549 	source = flex_array_get_ptr(policydb->type_val_to_struct_array,
550 				    scontext->type - 1);
551 	BUG_ON(!source);
552 
553 	if (!source->bounds)
554 		return;
555 
556 	target = flex_array_get_ptr(policydb->type_val_to_struct_array,
557 				    tcontext->type - 1);
558 	BUG_ON(!target);
559 
560 	memset(&lo_avd, 0, sizeof(lo_avd));
561 
562 	memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
563 	lo_scontext.type = source->bounds;
564 
565 	if (target->bounds) {
566 		memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
567 		lo_tcontext.type = target->bounds;
568 		tcontextp = &lo_tcontext;
569 	}
570 
571 	context_struct_compute_av(policydb, &lo_scontext,
572 				  tcontextp,
573 				  tclass,
574 				  &lo_avd,
575 				  NULL);
576 
577 	masked = ~lo_avd.allowed & avd->allowed;
578 
579 	if (likely(!masked))
580 		return;		/* no masked permission */
581 
582 	/* mask violated permissions */
583 	avd->allowed &= ~masked;
584 
585 	/* audit masked permissions */
586 	security_dump_masked_av(policydb, scontext, tcontext,
587 				tclass, masked, "bounds");
588 }
589 
590 /*
591  * flag which drivers have permissions
592  * only looking for ioctl based extended permssions
593  */
594 void services_compute_xperms_drivers(
595 		struct extended_perms *xperms,
596 		struct avtab_node *node)
597 {
598 	unsigned int i;
599 
600 	if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
601 		/* if one or more driver has all permissions allowed */
602 		for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
603 			xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
604 	} else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
605 		/* if allowing permissions within a driver */
606 		security_xperm_set(xperms->drivers.p,
607 					node->datum.u.xperms->driver);
608 	}
609 
610 	/* If no ioctl commands are allowed, ignore auditallow and auditdeny */
611 	if (node->key.specified & AVTAB_XPERMS_ALLOWED)
612 		xperms->len = 1;
613 }
614 
615 /*
616  * Compute access vectors and extended permissions based on a context
617  * structure pair for the permissions in a particular class.
618  */
619 static void context_struct_compute_av(struct policydb *policydb,
620 				      struct context *scontext,
621 				      struct context *tcontext,
622 				      u16 tclass,
623 				      struct av_decision *avd,
624 				      struct extended_perms *xperms)
625 {
626 	struct constraint_node *constraint;
627 	struct role_allow *ra;
628 	struct avtab_key avkey;
629 	struct avtab_node *node;
630 	struct class_datum *tclass_datum;
631 	struct ebitmap *sattr, *tattr;
632 	struct ebitmap_node *snode, *tnode;
633 	unsigned int i, j;
634 
635 	avd->allowed = 0;
636 	avd->auditallow = 0;
637 	avd->auditdeny = 0xffffffff;
638 	if (xperms) {
639 		memset(&xperms->drivers, 0, sizeof(xperms->drivers));
640 		xperms->len = 0;
641 	}
642 
643 	if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
644 		if (printk_ratelimit())
645 			pr_warn("SELinux:  Invalid class %hu\n", tclass);
646 		return;
647 	}
648 
649 	tclass_datum = policydb->class_val_to_struct[tclass - 1];
650 
651 	/*
652 	 * If a specific type enforcement rule was defined for
653 	 * this permission check, then use it.
654 	 */
655 	avkey.target_class = tclass;
656 	avkey.specified = AVTAB_AV | AVTAB_XPERMS;
657 	sattr = flex_array_get(policydb->type_attr_map_array,
658 			       scontext->type - 1);
659 	BUG_ON(!sattr);
660 	tattr = flex_array_get(policydb->type_attr_map_array,
661 			       tcontext->type - 1);
662 	BUG_ON(!tattr);
663 	ebitmap_for_each_positive_bit(sattr, snode, i) {
664 		ebitmap_for_each_positive_bit(tattr, tnode, j) {
665 			avkey.source_type = i + 1;
666 			avkey.target_type = j + 1;
667 			for (node = avtab_search_node(&policydb->te_avtab,
668 						      &avkey);
669 			     node;
670 			     node = avtab_search_node_next(node, avkey.specified)) {
671 				if (node->key.specified == AVTAB_ALLOWED)
672 					avd->allowed |= node->datum.u.data;
673 				else if (node->key.specified == AVTAB_AUDITALLOW)
674 					avd->auditallow |= node->datum.u.data;
675 				else if (node->key.specified == AVTAB_AUDITDENY)
676 					avd->auditdeny &= node->datum.u.data;
677 				else if (xperms && (node->key.specified & AVTAB_XPERMS))
678 					services_compute_xperms_drivers(xperms, node);
679 			}
680 
681 			/* Check conditional av table for additional permissions */
682 			cond_compute_av(&policydb->te_cond_avtab, &avkey,
683 					avd, xperms);
684 
685 		}
686 	}
687 
688 	/*
689 	 * Remove any permissions prohibited by a constraint (this includes
690 	 * the MLS policy).
691 	 */
692 	constraint = tclass_datum->constraints;
693 	while (constraint) {
694 		if ((constraint->permissions & (avd->allowed)) &&
695 		    !constraint_expr_eval(policydb, scontext, tcontext, NULL,
696 					  constraint->expr)) {
697 			avd->allowed &= ~(constraint->permissions);
698 		}
699 		constraint = constraint->next;
700 	}
701 
702 	/*
703 	 * If checking process transition permission and the
704 	 * role is changing, then check the (current_role, new_role)
705 	 * pair.
706 	 */
707 	if (tclass == policydb->process_class &&
708 	    (avd->allowed & policydb->process_trans_perms) &&
709 	    scontext->role != tcontext->role) {
710 		for (ra = policydb->role_allow; ra; ra = ra->next) {
711 			if (scontext->role == ra->role &&
712 			    tcontext->role == ra->new_role)
713 				break;
714 		}
715 		if (!ra)
716 			avd->allowed &= ~policydb->process_trans_perms;
717 	}
718 
719 	/*
720 	 * If the given source and target types have boundary
721 	 * constraint, lazy checks have to mask any violated
722 	 * permission and notice it to userspace via audit.
723 	 */
724 	type_attribute_bounds_av(policydb, scontext, tcontext,
725 				 tclass, avd);
726 }
727 
728 static int security_validtrans_handle_fail(struct selinux_state *state,
729 					   struct context *ocontext,
730 					   struct context *ncontext,
731 					   struct context *tcontext,
732 					   u16 tclass)
733 {
734 	struct policydb *p = &state->ss->policydb;
735 	char *o = NULL, *n = NULL, *t = NULL;
736 	u32 olen, nlen, tlen;
737 
738 	if (context_struct_to_string(p, ocontext, &o, &olen))
739 		goto out;
740 	if (context_struct_to_string(p, ncontext, &n, &nlen))
741 		goto out;
742 	if (context_struct_to_string(p, tcontext, &t, &tlen))
743 		goto out;
744 	audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
745 		  "op=security_validate_transition seresult=denied"
746 		  " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
747 		  o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
748 out:
749 	kfree(o);
750 	kfree(n);
751 	kfree(t);
752 
753 	if (!enforcing_enabled(state))
754 		return 0;
755 	return -EPERM;
756 }
757 
758 static int security_compute_validatetrans(struct selinux_state *state,
759 					  u32 oldsid, u32 newsid, u32 tasksid,
760 					  u16 orig_tclass, bool user)
761 {
762 	struct policydb *policydb;
763 	struct sidtab *sidtab;
764 	struct context *ocontext;
765 	struct context *ncontext;
766 	struct context *tcontext;
767 	struct class_datum *tclass_datum;
768 	struct constraint_node *constraint;
769 	u16 tclass;
770 	int rc = 0;
771 
772 
773 	if (!state->initialized)
774 		return 0;
775 
776 	read_lock(&state->ss->policy_rwlock);
777 
778 	policydb = &state->ss->policydb;
779 	sidtab = state->ss->sidtab;
780 
781 	if (!user)
782 		tclass = unmap_class(&state->ss->map, orig_tclass);
783 	else
784 		tclass = orig_tclass;
785 
786 	if (!tclass || tclass > policydb->p_classes.nprim) {
787 		rc = -EINVAL;
788 		goto out;
789 	}
790 	tclass_datum = policydb->class_val_to_struct[tclass - 1];
791 
792 	ocontext = sidtab_search(sidtab, oldsid);
793 	if (!ocontext) {
794 		pr_err("SELinux: %s:  unrecognized SID %d\n",
795 			__func__, oldsid);
796 		rc = -EINVAL;
797 		goto out;
798 	}
799 
800 	ncontext = sidtab_search(sidtab, newsid);
801 	if (!ncontext) {
802 		pr_err("SELinux: %s:  unrecognized SID %d\n",
803 			__func__, newsid);
804 		rc = -EINVAL;
805 		goto out;
806 	}
807 
808 	tcontext = sidtab_search(sidtab, tasksid);
809 	if (!tcontext) {
810 		pr_err("SELinux: %s:  unrecognized SID %d\n",
811 			__func__, tasksid);
812 		rc = -EINVAL;
813 		goto out;
814 	}
815 
816 	constraint = tclass_datum->validatetrans;
817 	while (constraint) {
818 		if (!constraint_expr_eval(policydb, ocontext, ncontext,
819 					  tcontext, constraint->expr)) {
820 			if (user)
821 				rc = -EPERM;
822 			else
823 				rc = security_validtrans_handle_fail(state,
824 								     ocontext,
825 								     ncontext,
826 								     tcontext,
827 								     tclass);
828 			goto out;
829 		}
830 		constraint = constraint->next;
831 	}
832 
833 out:
834 	read_unlock(&state->ss->policy_rwlock);
835 	return rc;
836 }
837 
838 int security_validate_transition_user(struct selinux_state *state,
839 				      u32 oldsid, u32 newsid, u32 tasksid,
840 				      u16 tclass)
841 {
842 	return security_compute_validatetrans(state, oldsid, newsid, tasksid,
843 					      tclass, true);
844 }
845 
846 int security_validate_transition(struct selinux_state *state,
847 				 u32 oldsid, u32 newsid, u32 tasksid,
848 				 u16 orig_tclass)
849 {
850 	return security_compute_validatetrans(state, oldsid, newsid, tasksid,
851 					      orig_tclass, false);
852 }
853 
854 /*
855  * security_bounded_transition - check whether the given
856  * transition is directed to bounded, or not.
857  * It returns 0, if @newsid is bounded by @oldsid.
858  * Otherwise, it returns error code.
859  *
860  * @oldsid : current security identifier
861  * @newsid : destinated security identifier
862  */
863 int security_bounded_transition(struct selinux_state *state,
864 				u32 old_sid, u32 new_sid)
865 {
866 	struct policydb *policydb;
867 	struct sidtab *sidtab;
868 	struct context *old_context, *new_context;
869 	struct type_datum *type;
870 	int index;
871 	int rc;
872 
873 	if (!state->initialized)
874 		return 0;
875 
876 	read_lock(&state->ss->policy_rwlock);
877 
878 	policydb = &state->ss->policydb;
879 	sidtab = state->ss->sidtab;
880 
881 	rc = -EINVAL;
882 	old_context = sidtab_search(sidtab, old_sid);
883 	if (!old_context) {
884 		pr_err("SELinux: %s: unrecognized SID %u\n",
885 		       __func__, old_sid);
886 		goto out;
887 	}
888 
889 	rc = -EINVAL;
890 	new_context = sidtab_search(sidtab, new_sid);
891 	if (!new_context) {
892 		pr_err("SELinux: %s: unrecognized SID %u\n",
893 		       __func__, new_sid);
894 		goto out;
895 	}
896 
897 	rc = 0;
898 	/* type/domain unchanged */
899 	if (old_context->type == new_context->type)
900 		goto out;
901 
902 	index = new_context->type;
903 	while (true) {
904 		type = flex_array_get_ptr(policydb->type_val_to_struct_array,
905 					  index - 1);
906 		BUG_ON(!type);
907 
908 		/* not bounded anymore */
909 		rc = -EPERM;
910 		if (!type->bounds)
911 			break;
912 
913 		/* @newsid is bounded by @oldsid */
914 		rc = 0;
915 		if (type->bounds == old_context->type)
916 			break;
917 
918 		index = type->bounds;
919 	}
920 
921 	if (rc) {
922 		char *old_name = NULL;
923 		char *new_name = NULL;
924 		u32 length;
925 
926 		if (!context_struct_to_string(policydb, old_context,
927 					      &old_name, &length) &&
928 		    !context_struct_to_string(policydb, new_context,
929 					      &new_name, &length)) {
930 			audit_log(audit_context(),
931 				  GFP_ATOMIC, AUDIT_SELINUX_ERR,
932 				  "op=security_bounded_transition "
933 				  "seresult=denied "
934 				  "oldcontext=%s newcontext=%s",
935 				  old_name, new_name);
936 		}
937 		kfree(new_name);
938 		kfree(old_name);
939 	}
940 out:
941 	read_unlock(&state->ss->policy_rwlock);
942 
943 	return rc;
944 }
945 
946 static void avd_init(struct selinux_state *state, struct av_decision *avd)
947 {
948 	avd->allowed = 0;
949 	avd->auditallow = 0;
950 	avd->auditdeny = 0xffffffff;
951 	avd->seqno = state->ss->latest_granting;
952 	avd->flags = 0;
953 }
954 
955 void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
956 					struct avtab_node *node)
957 {
958 	unsigned int i;
959 
960 	if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
961 		if (xpermd->driver != node->datum.u.xperms->driver)
962 			return;
963 	} else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
964 		if (!security_xperm_test(node->datum.u.xperms->perms.p,
965 					xpermd->driver))
966 			return;
967 	} else {
968 		BUG();
969 	}
970 
971 	if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
972 		xpermd->used |= XPERMS_ALLOWED;
973 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
974 			memset(xpermd->allowed->p, 0xff,
975 					sizeof(xpermd->allowed->p));
976 		}
977 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
978 			for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++)
979 				xpermd->allowed->p[i] |=
980 					node->datum.u.xperms->perms.p[i];
981 		}
982 	} else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
983 		xpermd->used |= XPERMS_AUDITALLOW;
984 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
985 			memset(xpermd->auditallow->p, 0xff,
986 					sizeof(xpermd->auditallow->p));
987 		}
988 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
989 			for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++)
990 				xpermd->auditallow->p[i] |=
991 					node->datum.u.xperms->perms.p[i];
992 		}
993 	} else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
994 		xpermd->used |= XPERMS_DONTAUDIT;
995 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
996 			memset(xpermd->dontaudit->p, 0xff,
997 					sizeof(xpermd->dontaudit->p));
998 		}
999 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
1000 			for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++)
1001 				xpermd->dontaudit->p[i] |=
1002 					node->datum.u.xperms->perms.p[i];
1003 		}
1004 	} else {
1005 		BUG();
1006 	}
1007 }
1008 
1009 void security_compute_xperms_decision(struct selinux_state *state,
1010 				      u32 ssid,
1011 				      u32 tsid,
1012 				      u16 orig_tclass,
1013 				      u8 driver,
1014 				      struct extended_perms_decision *xpermd)
1015 {
1016 	struct policydb *policydb;
1017 	struct sidtab *sidtab;
1018 	u16 tclass;
1019 	struct context *scontext, *tcontext;
1020 	struct avtab_key avkey;
1021 	struct avtab_node *node;
1022 	struct ebitmap *sattr, *tattr;
1023 	struct ebitmap_node *snode, *tnode;
1024 	unsigned int i, j;
1025 
1026 	xpermd->driver = driver;
1027 	xpermd->used = 0;
1028 	memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1029 	memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1030 	memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1031 
1032 	read_lock(&state->ss->policy_rwlock);
1033 	if (!state->initialized)
1034 		goto allow;
1035 
1036 	policydb = &state->ss->policydb;
1037 	sidtab = state->ss->sidtab;
1038 
1039 	scontext = sidtab_search(sidtab, ssid);
1040 	if (!scontext) {
1041 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1042 		       __func__, ssid);
1043 		goto out;
1044 	}
1045 
1046 	tcontext = sidtab_search(sidtab, tsid);
1047 	if (!tcontext) {
1048 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1049 		       __func__, tsid);
1050 		goto out;
1051 	}
1052 
1053 	tclass = unmap_class(&state->ss->map, orig_tclass);
1054 	if (unlikely(orig_tclass && !tclass)) {
1055 		if (policydb->allow_unknown)
1056 			goto allow;
1057 		goto out;
1058 	}
1059 
1060 
1061 	if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1062 		pr_warn_ratelimited("SELinux:  Invalid class %hu\n", tclass);
1063 		goto out;
1064 	}
1065 
1066 	avkey.target_class = tclass;
1067 	avkey.specified = AVTAB_XPERMS;
1068 	sattr = flex_array_get(policydb->type_attr_map_array,
1069 				scontext->type - 1);
1070 	BUG_ON(!sattr);
1071 	tattr = flex_array_get(policydb->type_attr_map_array,
1072 				tcontext->type - 1);
1073 	BUG_ON(!tattr);
1074 	ebitmap_for_each_positive_bit(sattr, snode, i) {
1075 		ebitmap_for_each_positive_bit(tattr, tnode, j) {
1076 			avkey.source_type = i + 1;
1077 			avkey.target_type = j + 1;
1078 			for (node = avtab_search_node(&policydb->te_avtab,
1079 						      &avkey);
1080 			     node;
1081 			     node = avtab_search_node_next(node, avkey.specified))
1082 				services_compute_xperms_decision(xpermd, node);
1083 
1084 			cond_compute_xperms(&policydb->te_cond_avtab,
1085 						&avkey, xpermd);
1086 		}
1087 	}
1088 out:
1089 	read_unlock(&state->ss->policy_rwlock);
1090 	return;
1091 allow:
1092 	memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1093 	goto out;
1094 }
1095 
1096 /**
1097  * security_compute_av - Compute access vector decisions.
1098  * @ssid: source security identifier
1099  * @tsid: target security identifier
1100  * @tclass: target security class
1101  * @avd: access vector decisions
1102  * @xperms: extended permissions
1103  *
1104  * Compute a set of access vector decisions based on the
1105  * SID pair (@ssid, @tsid) for the permissions in @tclass.
1106  */
1107 void security_compute_av(struct selinux_state *state,
1108 			 u32 ssid,
1109 			 u32 tsid,
1110 			 u16 orig_tclass,
1111 			 struct av_decision *avd,
1112 			 struct extended_perms *xperms)
1113 {
1114 	struct policydb *policydb;
1115 	struct sidtab *sidtab;
1116 	u16 tclass;
1117 	struct context *scontext = NULL, *tcontext = NULL;
1118 
1119 	read_lock(&state->ss->policy_rwlock);
1120 	avd_init(state, avd);
1121 	xperms->len = 0;
1122 	if (!state->initialized)
1123 		goto allow;
1124 
1125 	policydb = &state->ss->policydb;
1126 	sidtab = state->ss->sidtab;
1127 
1128 	scontext = sidtab_search(sidtab, ssid);
1129 	if (!scontext) {
1130 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1131 		       __func__, ssid);
1132 		goto out;
1133 	}
1134 
1135 	/* permissive domain? */
1136 	if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1137 		avd->flags |= AVD_FLAGS_PERMISSIVE;
1138 
1139 	tcontext = sidtab_search(sidtab, tsid);
1140 	if (!tcontext) {
1141 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1142 		       __func__, tsid);
1143 		goto out;
1144 	}
1145 
1146 	tclass = unmap_class(&state->ss->map, orig_tclass);
1147 	if (unlikely(orig_tclass && !tclass)) {
1148 		if (policydb->allow_unknown)
1149 			goto allow;
1150 		goto out;
1151 	}
1152 	context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1153 				  xperms);
1154 	map_decision(&state->ss->map, orig_tclass, avd,
1155 		     policydb->allow_unknown);
1156 out:
1157 	read_unlock(&state->ss->policy_rwlock);
1158 	return;
1159 allow:
1160 	avd->allowed = 0xffffffff;
1161 	goto out;
1162 }
1163 
1164 void security_compute_av_user(struct selinux_state *state,
1165 			      u32 ssid,
1166 			      u32 tsid,
1167 			      u16 tclass,
1168 			      struct av_decision *avd)
1169 {
1170 	struct policydb *policydb;
1171 	struct sidtab *sidtab;
1172 	struct context *scontext = NULL, *tcontext = NULL;
1173 
1174 	read_lock(&state->ss->policy_rwlock);
1175 	avd_init(state, avd);
1176 	if (!state->initialized)
1177 		goto allow;
1178 
1179 	policydb = &state->ss->policydb;
1180 	sidtab = state->ss->sidtab;
1181 
1182 	scontext = sidtab_search(sidtab, ssid);
1183 	if (!scontext) {
1184 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1185 		       __func__, ssid);
1186 		goto out;
1187 	}
1188 
1189 	/* permissive domain? */
1190 	if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1191 		avd->flags |= AVD_FLAGS_PERMISSIVE;
1192 
1193 	tcontext = sidtab_search(sidtab, tsid);
1194 	if (!tcontext) {
1195 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1196 		       __func__, tsid);
1197 		goto out;
1198 	}
1199 
1200 	if (unlikely(!tclass)) {
1201 		if (policydb->allow_unknown)
1202 			goto allow;
1203 		goto out;
1204 	}
1205 
1206 	context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1207 				  NULL);
1208  out:
1209 	read_unlock(&state->ss->policy_rwlock);
1210 	return;
1211 allow:
1212 	avd->allowed = 0xffffffff;
1213 	goto out;
1214 }
1215 
1216 /*
1217  * Write the security context string representation of
1218  * the context structure `context' into a dynamically
1219  * allocated string of the correct size.  Set `*scontext'
1220  * to point to this string and set `*scontext_len' to
1221  * the length of the string.
1222  */
1223 static int context_struct_to_string(struct policydb *p,
1224 				    struct context *context,
1225 				    char **scontext, u32 *scontext_len)
1226 {
1227 	char *scontextp;
1228 
1229 	if (scontext)
1230 		*scontext = NULL;
1231 	*scontext_len = 0;
1232 
1233 	if (context->len) {
1234 		*scontext_len = context->len;
1235 		if (scontext) {
1236 			*scontext = kstrdup(context->str, GFP_ATOMIC);
1237 			if (!(*scontext))
1238 				return -ENOMEM;
1239 		}
1240 		return 0;
1241 	}
1242 
1243 	/* Compute the size of the context. */
1244 	*scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1245 	*scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1246 	*scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1247 	*scontext_len += mls_compute_context_len(p, context);
1248 
1249 	if (!scontext)
1250 		return 0;
1251 
1252 	/* Allocate space for the context; caller must free this space. */
1253 	scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1254 	if (!scontextp)
1255 		return -ENOMEM;
1256 	*scontext = scontextp;
1257 
1258 	/*
1259 	 * Copy the user name, role name and type name into the context.
1260 	 */
1261 	scontextp += sprintf(scontextp, "%s:%s:%s",
1262 		sym_name(p, SYM_USERS, context->user - 1),
1263 		sym_name(p, SYM_ROLES, context->role - 1),
1264 		sym_name(p, SYM_TYPES, context->type - 1));
1265 
1266 	mls_sid_to_context(p, context, &scontextp);
1267 
1268 	*scontextp = 0;
1269 
1270 	return 0;
1271 }
1272 
1273 #include "initial_sid_to_string.h"
1274 
1275 const char *security_get_initial_sid_context(u32 sid)
1276 {
1277 	if (unlikely(sid > SECINITSID_NUM))
1278 		return NULL;
1279 	return initial_sid_to_string[sid];
1280 }
1281 
1282 static int security_sid_to_context_core(struct selinux_state *state,
1283 					u32 sid, char **scontext,
1284 					u32 *scontext_len, int force)
1285 {
1286 	struct policydb *policydb;
1287 	struct sidtab *sidtab;
1288 	struct context *context;
1289 	int rc = 0;
1290 
1291 	if (scontext)
1292 		*scontext = NULL;
1293 	*scontext_len  = 0;
1294 
1295 	if (!state->initialized) {
1296 		if (sid <= SECINITSID_NUM) {
1297 			char *scontextp;
1298 
1299 			*scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1300 			if (!scontext)
1301 				goto out;
1302 			scontextp = kmemdup(initial_sid_to_string[sid],
1303 					    *scontext_len, GFP_ATOMIC);
1304 			if (!scontextp) {
1305 				rc = -ENOMEM;
1306 				goto out;
1307 			}
1308 			*scontext = scontextp;
1309 			goto out;
1310 		}
1311 		pr_err("SELinux: %s:  called before initial "
1312 		       "load_policy on unknown SID %d\n", __func__, sid);
1313 		rc = -EINVAL;
1314 		goto out;
1315 	}
1316 	read_lock(&state->ss->policy_rwlock);
1317 	policydb = &state->ss->policydb;
1318 	sidtab = state->ss->sidtab;
1319 	if (force)
1320 		context = sidtab_search_force(sidtab, sid);
1321 	else
1322 		context = sidtab_search(sidtab, sid);
1323 	if (!context) {
1324 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1325 			__func__, sid);
1326 		rc = -EINVAL;
1327 		goto out_unlock;
1328 	}
1329 	rc = context_struct_to_string(policydb, context, scontext,
1330 				      scontext_len);
1331 out_unlock:
1332 	read_unlock(&state->ss->policy_rwlock);
1333 out:
1334 	return rc;
1335 
1336 }
1337 
1338 /**
1339  * security_sid_to_context - Obtain a context for a given SID.
1340  * @sid: security identifier, SID
1341  * @scontext: security context
1342  * @scontext_len: length in bytes
1343  *
1344  * Write the string representation of the context associated with @sid
1345  * into a dynamically allocated string of the correct size.  Set @scontext
1346  * to point to this string and set @scontext_len to the length of the string.
1347  */
1348 int security_sid_to_context(struct selinux_state *state,
1349 			    u32 sid, char **scontext, u32 *scontext_len)
1350 {
1351 	return security_sid_to_context_core(state, sid, scontext,
1352 					    scontext_len, 0);
1353 }
1354 
1355 int security_sid_to_context_force(struct selinux_state *state, u32 sid,
1356 				  char **scontext, u32 *scontext_len)
1357 {
1358 	return security_sid_to_context_core(state, sid, scontext,
1359 					    scontext_len, 1);
1360 }
1361 
1362 /*
1363  * Caveat:  Mutates scontext.
1364  */
1365 static int string_to_context_struct(struct policydb *pol,
1366 				    struct sidtab *sidtabp,
1367 				    char *scontext,
1368 				    struct context *ctx,
1369 				    u32 def_sid)
1370 {
1371 	struct role_datum *role;
1372 	struct type_datum *typdatum;
1373 	struct user_datum *usrdatum;
1374 	char *scontextp, *p, oldc;
1375 	int rc = 0;
1376 
1377 	context_init(ctx);
1378 
1379 	/* Parse the security context. */
1380 
1381 	rc = -EINVAL;
1382 	scontextp = (char *) scontext;
1383 
1384 	/* Extract the user. */
1385 	p = scontextp;
1386 	while (*p && *p != ':')
1387 		p++;
1388 
1389 	if (*p == 0)
1390 		goto out;
1391 
1392 	*p++ = 0;
1393 
1394 	usrdatum = hashtab_search(pol->p_users.table, scontextp);
1395 	if (!usrdatum)
1396 		goto out;
1397 
1398 	ctx->user = usrdatum->value;
1399 
1400 	/* Extract role. */
1401 	scontextp = p;
1402 	while (*p && *p != ':')
1403 		p++;
1404 
1405 	if (*p == 0)
1406 		goto out;
1407 
1408 	*p++ = 0;
1409 
1410 	role = hashtab_search(pol->p_roles.table, scontextp);
1411 	if (!role)
1412 		goto out;
1413 	ctx->role = role->value;
1414 
1415 	/* Extract type. */
1416 	scontextp = p;
1417 	while (*p && *p != ':')
1418 		p++;
1419 	oldc = *p;
1420 	*p++ = 0;
1421 
1422 	typdatum = hashtab_search(pol->p_types.table, scontextp);
1423 	if (!typdatum || typdatum->attribute)
1424 		goto out;
1425 
1426 	ctx->type = typdatum->value;
1427 
1428 	rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid);
1429 	if (rc)
1430 		goto out;
1431 
1432 	/* Check the validity of the new context. */
1433 	rc = -EINVAL;
1434 	if (!policydb_context_isvalid(pol, ctx))
1435 		goto out;
1436 	rc = 0;
1437 out:
1438 	if (rc)
1439 		context_destroy(ctx);
1440 	return rc;
1441 }
1442 
1443 static int security_context_to_sid_core(struct selinux_state *state,
1444 					const char *scontext, u32 scontext_len,
1445 					u32 *sid, u32 def_sid, gfp_t gfp_flags,
1446 					int force)
1447 {
1448 	struct policydb *policydb;
1449 	struct sidtab *sidtab;
1450 	char *scontext2, *str = NULL;
1451 	struct context context;
1452 	int rc = 0;
1453 
1454 	/* An empty security context is never valid. */
1455 	if (!scontext_len)
1456 		return -EINVAL;
1457 
1458 	/* Copy the string to allow changes and ensure a NUL terminator */
1459 	scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags);
1460 	if (!scontext2)
1461 		return -ENOMEM;
1462 
1463 	if (!state->initialized) {
1464 		int i;
1465 
1466 		for (i = 1; i < SECINITSID_NUM; i++) {
1467 			if (!strcmp(initial_sid_to_string[i], scontext2)) {
1468 				*sid = i;
1469 				goto out;
1470 			}
1471 		}
1472 		*sid = SECINITSID_KERNEL;
1473 		goto out;
1474 	}
1475 	*sid = SECSID_NULL;
1476 
1477 	if (force) {
1478 		/* Save another copy for storing in uninterpreted form */
1479 		rc = -ENOMEM;
1480 		str = kstrdup(scontext2, gfp_flags);
1481 		if (!str)
1482 			goto out;
1483 	}
1484 	read_lock(&state->ss->policy_rwlock);
1485 	policydb = &state->ss->policydb;
1486 	sidtab = state->ss->sidtab;
1487 	rc = string_to_context_struct(policydb, sidtab, scontext2,
1488 				      &context, def_sid);
1489 	if (rc == -EINVAL && force) {
1490 		context.str = str;
1491 		context.len = strlen(str) + 1;
1492 		str = NULL;
1493 	} else if (rc)
1494 		goto out_unlock;
1495 	rc = sidtab_context_to_sid(sidtab, &context, sid);
1496 	context_destroy(&context);
1497 out_unlock:
1498 	read_unlock(&state->ss->policy_rwlock);
1499 out:
1500 	kfree(scontext2);
1501 	kfree(str);
1502 	return rc;
1503 }
1504 
1505 /**
1506  * security_context_to_sid - Obtain a SID for a given security context.
1507  * @scontext: security context
1508  * @scontext_len: length in bytes
1509  * @sid: security identifier, SID
1510  * @gfp: context for the allocation
1511  *
1512  * Obtains a SID associated with the security context that
1513  * has the string representation specified by @scontext.
1514  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1515  * memory is available, or 0 on success.
1516  */
1517 int security_context_to_sid(struct selinux_state *state,
1518 			    const char *scontext, u32 scontext_len, u32 *sid,
1519 			    gfp_t gfp)
1520 {
1521 	return security_context_to_sid_core(state, scontext, scontext_len,
1522 					    sid, SECSID_NULL, gfp, 0);
1523 }
1524 
1525 int security_context_str_to_sid(struct selinux_state *state,
1526 				const char *scontext, u32 *sid, gfp_t gfp)
1527 {
1528 	return security_context_to_sid(state, scontext, strlen(scontext),
1529 				       sid, gfp);
1530 }
1531 
1532 /**
1533  * security_context_to_sid_default - Obtain a SID for a given security context,
1534  * falling back to specified default if needed.
1535  *
1536  * @scontext: security context
1537  * @scontext_len: length in bytes
1538  * @sid: security identifier, SID
1539  * @def_sid: default SID to assign on error
1540  *
1541  * Obtains a SID associated with the security context that
1542  * has the string representation specified by @scontext.
1543  * The default SID is passed to the MLS layer to be used to allow
1544  * kernel labeling of the MLS field if the MLS field is not present
1545  * (for upgrading to MLS without full relabel).
1546  * Implicitly forces adding of the context even if it cannot be mapped yet.
1547  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1548  * memory is available, or 0 on success.
1549  */
1550 int security_context_to_sid_default(struct selinux_state *state,
1551 				    const char *scontext, u32 scontext_len,
1552 				    u32 *sid, u32 def_sid, gfp_t gfp_flags)
1553 {
1554 	return security_context_to_sid_core(state, scontext, scontext_len,
1555 					    sid, def_sid, gfp_flags, 1);
1556 }
1557 
1558 int security_context_to_sid_force(struct selinux_state *state,
1559 				  const char *scontext, u32 scontext_len,
1560 				  u32 *sid)
1561 {
1562 	return security_context_to_sid_core(state, scontext, scontext_len,
1563 					    sid, SECSID_NULL, GFP_KERNEL, 1);
1564 }
1565 
1566 static int compute_sid_handle_invalid_context(
1567 	struct selinux_state *state,
1568 	struct context *scontext,
1569 	struct context *tcontext,
1570 	u16 tclass,
1571 	struct context *newcontext)
1572 {
1573 	struct policydb *policydb = &state->ss->policydb;
1574 	char *s = NULL, *t = NULL, *n = NULL;
1575 	u32 slen, tlen, nlen;
1576 
1577 	if (context_struct_to_string(policydb, scontext, &s, &slen))
1578 		goto out;
1579 	if (context_struct_to_string(policydb, tcontext, &t, &tlen))
1580 		goto out;
1581 	if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1582 		goto out;
1583 	audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
1584 		  "op=security_compute_sid invalid_context=%s"
1585 		  " scontext=%s"
1586 		  " tcontext=%s"
1587 		  " tclass=%s",
1588 		  n, s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1589 out:
1590 	kfree(s);
1591 	kfree(t);
1592 	kfree(n);
1593 	if (!enforcing_enabled(state))
1594 		return 0;
1595 	return -EACCES;
1596 }
1597 
1598 static void filename_compute_type(struct policydb *policydb,
1599 				  struct context *newcontext,
1600 				  u32 stype, u32 ttype, u16 tclass,
1601 				  const char *objname)
1602 {
1603 	struct filename_trans ft;
1604 	struct filename_trans_datum *otype;
1605 
1606 	/*
1607 	 * Most filename trans rules are going to live in specific directories
1608 	 * like /dev or /var/run.  This bitmap will quickly skip rule searches
1609 	 * if the ttype does not contain any rules.
1610 	 */
1611 	if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1612 		return;
1613 
1614 	ft.stype = stype;
1615 	ft.ttype = ttype;
1616 	ft.tclass = tclass;
1617 	ft.name = objname;
1618 
1619 	otype = hashtab_search(policydb->filename_trans, &ft);
1620 	if (otype)
1621 		newcontext->type = otype->otype;
1622 }
1623 
1624 static int security_compute_sid(struct selinux_state *state,
1625 				u32 ssid,
1626 				u32 tsid,
1627 				u16 orig_tclass,
1628 				u32 specified,
1629 				const char *objname,
1630 				u32 *out_sid,
1631 				bool kern)
1632 {
1633 	struct policydb *policydb;
1634 	struct sidtab *sidtab;
1635 	struct class_datum *cladatum = NULL;
1636 	struct context *scontext = NULL, *tcontext = NULL, newcontext;
1637 	struct role_trans *roletr = NULL;
1638 	struct avtab_key avkey;
1639 	struct avtab_datum *avdatum;
1640 	struct avtab_node *node;
1641 	u16 tclass;
1642 	int rc = 0;
1643 	bool sock;
1644 
1645 	if (!state->initialized) {
1646 		switch (orig_tclass) {
1647 		case SECCLASS_PROCESS: /* kernel value */
1648 			*out_sid = ssid;
1649 			break;
1650 		default:
1651 			*out_sid = tsid;
1652 			break;
1653 		}
1654 		goto out;
1655 	}
1656 
1657 	context_init(&newcontext);
1658 
1659 	read_lock(&state->ss->policy_rwlock);
1660 
1661 	if (kern) {
1662 		tclass = unmap_class(&state->ss->map, orig_tclass);
1663 		sock = security_is_socket_class(orig_tclass);
1664 	} else {
1665 		tclass = orig_tclass;
1666 		sock = security_is_socket_class(map_class(&state->ss->map,
1667 							  tclass));
1668 	}
1669 
1670 	policydb = &state->ss->policydb;
1671 	sidtab = state->ss->sidtab;
1672 
1673 	scontext = sidtab_search(sidtab, ssid);
1674 	if (!scontext) {
1675 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1676 		       __func__, ssid);
1677 		rc = -EINVAL;
1678 		goto out_unlock;
1679 	}
1680 	tcontext = sidtab_search(sidtab, tsid);
1681 	if (!tcontext) {
1682 		pr_err("SELinux: %s:  unrecognized SID %d\n",
1683 		       __func__, tsid);
1684 		rc = -EINVAL;
1685 		goto out_unlock;
1686 	}
1687 
1688 	if (tclass && tclass <= policydb->p_classes.nprim)
1689 		cladatum = policydb->class_val_to_struct[tclass - 1];
1690 
1691 	/* Set the user identity. */
1692 	switch (specified) {
1693 	case AVTAB_TRANSITION:
1694 	case AVTAB_CHANGE:
1695 		if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1696 			newcontext.user = tcontext->user;
1697 		} else {
1698 			/* notice this gets both DEFAULT_SOURCE and unset */
1699 			/* Use the process user identity. */
1700 			newcontext.user = scontext->user;
1701 		}
1702 		break;
1703 	case AVTAB_MEMBER:
1704 		/* Use the related object owner. */
1705 		newcontext.user = tcontext->user;
1706 		break;
1707 	}
1708 
1709 	/* Set the role to default values. */
1710 	if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1711 		newcontext.role = scontext->role;
1712 	} else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1713 		newcontext.role = tcontext->role;
1714 	} else {
1715 		if ((tclass == policydb->process_class) || (sock == true))
1716 			newcontext.role = scontext->role;
1717 		else
1718 			newcontext.role = OBJECT_R_VAL;
1719 	}
1720 
1721 	/* Set the type to default values. */
1722 	if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1723 		newcontext.type = scontext->type;
1724 	} else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1725 		newcontext.type = tcontext->type;
1726 	} else {
1727 		if ((tclass == policydb->process_class) || (sock == true)) {
1728 			/* Use the type of process. */
1729 			newcontext.type = scontext->type;
1730 		} else {
1731 			/* Use the type of the related object. */
1732 			newcontext.type = tcontext->type;
1733 		}
1734 	}
1735 
1736 	/* Look for a type transition/member/change rule. */
1737 	avkey.source_type = scontext->type;
1738 	avkey.target_type = tcontext->type;
1739 	avkey.target_class = tclass;
1740 	avkey.specified = specified;
1741 	avdatum = avtab_search(&policydb->te_avtab, &avkey);
1742 
1743 	/* If no permanent rule, also check for enabled conditional rules */
1744 	if (!avdatum) {
1745 		node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1746 		for (; node; node = avtab_search_node_next(node, specified)) {
1747 			if (node->key.specified & AVTAB_ENABLED) {
1748 				avdatum = &node->datum;
1749 				break;
1750 			}
1751 		}
1752 	}
1753 
1754 	if (avdatum) {
1755 		/* Use the type from the type transition/member/change rule. */
1756 		newcontext.type = avdatum->u.data;
1757 	}
1758 
1759 	/* if we have a objname this is a file trans check so check those rules */
1760 	if (objname)
1761 		filename_compute_type(policydb, &newcontext, scontext->type,
1762 				      tcontext->type, tclass, objname);
1763 
1764 	/* Check for class-specific changes. */
1765 	if (specified & AVTAB_TRANSITION) {
1766 		/* Look for a role transition rule. */
1767 		for (roletr = policydb->role_tr; roletr;
1768 		     roletr = roletr->next) {
1769 			if ((roletr->role == scontext->role) &&
1770 			    (roletr->type == tcontext->type) &&
1771 			    (roletr->tclass == tclass)) {
1772 				/* Use the role transition rule. */
1773 				newcontext.role = roletr->new_role;
1774 				break;
1775 			}
1776 		}
1777 	}
1778 
1779 	/* Set the MLS attributes.
1780 	   This is done last because it may allocate memory. */
1781 	rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1782 			     &newcontext, sock);
1783 	if (rc)
1784 		goto out_unlock;
1785 
1786 	/* Check the validity of the context. */
1787 	if (!policydb_context_isvalid(policydb, &newcontext)) {
1788 		rc = compute_sid_handle_invalid_context(state, scontext,
1789 							tcontext,
1790 							tclass,
1791 							&newcontext);
1792 		if (rc)
1793 			goto out_unlock;
1794 	}
1795 	/* Obtain the sid for the context. */
1796 	rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1797 out_unlock:
1798 	read_unlock(&state->ss->policy_rwlock);
1799 	context_destroy(&newcontext);
1800 out:
1801 	return rc;
1802 }
1803 
1804 /**
1805  * security_transition_sid - Compute the SID for a new subject/object.
1806  * @ssid: source security identifier
1807  * @tsid: target security identifier
1808  * @tclass: target security class
1809  * @out_sid: security identifier for new subject/object
1810  *
1811  * Compute a SID to use for labeling a new subject or object in the
1812  * class @tclass based on a SID pair (@ssid, @tsid).
1813  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1814  * if insufficient memory is available, or %0 if the new SID was
1815  * computed successfully.
1816  */
1817 int security_transition_sid(struct selinux_state *state,
1818 			    u32 ssid, u32 tsid, u16 tclass,
1819 			    const struct qstr *qstr, u32 *out_sid)
1820 {
1821 	return security_compute_sid(state, ssid, tsid, tclass,
1822 				    AVTAB_TRANSITION,
1823 				    qstr ? qstr->name : NULL, out_sid, true);
1824 }
1825 
1826 int security_transition_sid_user(struct selinux_state *state,
1827 				 u32 ssid, u32 tsid, u16 tclass,
1828 				 const char *objname, u32 *out_sid)
1829 {
1830 	return security_compute_sid(state, ssid, tsid, tclass,
1831 				    AVTAB_TRANSITION,
1832 				    objname, out_sid, false);
1833 }
1834 
1835 /**
1836  * security_member_sid - Compute the SID for member selection.
1837  * @ssid: source security identifier
1838  * @tsid: target security identifier
1839  * @tclass: target security class
1840  * @out_sid: security identifier for selected member
1841  *
1842  * Compute a SID to use when selecting a member of a polyinstantiated
1843  * object of class @tclass based on a SID pair (@ssid, @tsid).
1844  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1845  * if insufficient memory is available, or %0 if the SID was
1846  * computed successfully.
1847  */
1848 int security_member_sid(struct selinux_state *state,
1849 			u32 ssid,
1850 			u32 tsid,
1851 			u16 tclass,
1852 			u32 *out_sid)
1853 {
1854 	return security_compute_sid(state, ssid, tsid, tclass,
1855 				    AVTAB_MEMBER, NULL,
1856 				    out_sid, false);
1857 }
1858 
1859 /**
1860  * security_change_sid - Compute the SID for object relabeling.
1861  * @ssid: source security identifier
1862  * @tsid: target security identifier
1863  * @tclass: target security class
1864  * @out_sid: security identifier for selected member
1865  *
1866  * Compute a SID to use for relabeling an object of class @tclass
1867  * based on a SID pair (@ssid, @tsid).
1868  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1869  * if insufficient memory is available, or %0 if the SID was
1870  * computed successfully.
1871  */
1872 int security_change_sid(struct selinux_state *state,
1873 			u32 ssid,
1874 			u32 tsid,
1875 			u16 tclass,
1876 			u32 *out_sid)
1877 {
1878 	return security_compute_sid(state,
1879 				    ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1880 				    out_sid, false);
1881 }
1882 
1883 static inline int convert_context_handle_invalid_context(
1884 	struct selinux_state *state,
1885 	struct context *context)
1886 {
1887 	struct policydb *policydb = &state->ss->policydb;
1888 	char *s;
1889 	u32 len;
1890 
1891 	if (enforcing_enabled(state))
1892 		return -EINVAL;
1893 
1894 	if (!context_struct_to_string(policydb, context, &s, &len)) {
1895 		pr_warn("SELinux:  Context %s would be invalid if enforcing\n",
1896 			s);
1897 		kfree(s);
1898 	}
1899 	return 0;
1900 }
1901 
1902 struct convert_context_args {
1903 	struct selinux_state *state;
1904 	struct policydb *oldp;
1905 	struct policydb *newp;
1906 };
1907 
1908 /*
1909  * Convert the values in the security context
1910  * structure `oldc' from the values specified
1911  * in the policy `p->oldp' to the values specified
1912  * in the policy `p->newp', storing the new context
1913  * in `newc'.  Verify that the context is valid
1914  * under the new policy.
1915  */
1916 static int convert_context(struct context *oldc, struct context *newc, void *p)
1917 {
1918 	struct convert_context_args *args;
1919 	struct ocontext *oc;
1920 	struct role_datum *role;
1921 	struct type_datum *typdatum;
1922 	struct user_datum *usrdatum;
1923 	char *s;
1924 	u32 len;
1925 	int rc;
1926 
1927 	args = p;
1928 
1929 	if (oldc->str) {
1930 		s = kstrdup(oldc->str, GFP_KERNEL);
1931 		if (!s)
1932 			return -ENOMEM;
1933 
1934 		rc = string_to_context_struct(args->newp, NULL, s,
1935 					      newc, SECSID_NULL);
1936 		if (rc == -EINVAL) {
1937 			/* Retain string representation for later mapping. */
1938 			context_init(newc);
1939 			newc->str = s;
1940 			newc->len = oldc->len;
1941 			return 0;
1942 		}
1943 		kfree(s);
1944 		if (rc) {
1945 			/* Other error condition, e.g. ENOMEM. */
1946 			pr_err("SELinux:   Unable to map context %s, rc = %d.\n",
1947 			       oldc->str, -rc);
1948 			return rc;
1949 		}
1950 		pr_info("SELinux:  Context %s became valid (mapped).\n",
1951 			oldc->str);
1952 		return 0;
1953 	}
1954 
1955 	context_init(newc);
1956 
1957 	/* Convert the user. */
1958 	rc = -EINVAL;
1959 	usrdatum = hashtab_search(args->newp->p_users.table,
1960 				  sym_name(args->oldp,
1961 					   SYM_USERS, oldc->user - 1));
1962 	if (!usrdatum)
1963 		goto bad;
1964 	newc->user = usrdatum->value;
1965 
1966 	/* Convert the role. */
1967 	rc = -EINVAL;
1968 	role = hashtab_search(args->newp->p_roles.table,
1969 			      sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
1970 	if (!role)
1971 		goto bad;
1972 	newc->role = role->value;
1973 
1974 	/* Convert the type. */
1975 	rc = -EINVAL;
1976 	typdatum = hashtab_search(args->newp->p_types.table,
1977 				  sym_name(args->oldp,
1978 					   SYM_TYPES, oldc->type - 1));
1979 	if (!typdatum)
1980 		goto bad;
1981 	newc->type = typdatum->value;
1982 
1983 	/* Convert the MLS fields if dealing with MLS policies */
1984 	if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1985 		rc = mls_convert_context(args->oldp, args->newp, oldc, newc);
1986 		if (rc)
1987 			goto bad;
1988 	} else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1989 		/*
1990 		 * Switching between non-MLS and MLS policy:
1991 		 * ensure that the MLS fields of the context for all
1992 		 * existing entries in the sidtab are filled in with a
1993 		 * suitable default value, likely taken from one of the
1994 		 * initial SIDs.
1995 		 */
1996 		oc = args->newp->ocontexts[OCON_ISID];
1997 		while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1998 			oc = oc->next;
1999 		rc = -EINVAL;
2000 		if (!oc) {
2001 			pr_err("SELinux:  unable to look up"
2002 				" the initial SIDs list\n");
2003 			goto bad;
2004 		}
2005 		rc = mls_range_set(newc, &oc->context[0].range);
2006 		if (rc)
2007 			goto bad;
2008 	}
2009 
2010 	/* Check the validity of the new context. */
2011 	if (!policydb_context_isvalid(args->newp, newc)) {
2012 		rc = convert_context_handle_invalid_context(args->state, oldc);
2013 		if (rc)
2014 			goto bad;
2015 	}
2016 
2017 	return 0;
2018 bad:
2019 	/* Map old representation to string and save it. */
2020 	rc = context_struct_to_string(args->oldp, oldc, &s, &len);
2021 	if (rc)
2022 		return rc;
2023 	context_destroy(newc);
2024 	newc->str = s;
2025 	newc->len = len;
2026 	pr_info("SELinux:  Context %s became invalid (unmapped).\n",
2027 		newc->str);
2028 	return 0;
2029 }
2030 
2031 static void security_load_policycaps(struct selinux_state *state)
2032 {
2033 	struct policydb *p = &state->ss->policydb;
2034 	unsigned int i;
2035 	struct ebitmap_node *node;
2036 
2037 	for (i = 0; i < ARRAY_SIZE(state->policycap); i++)
2038 		state->policycap[i] = ebitmap_get_bit(&p->policycaps, i);
2039 
2040 	for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2041 		pr_info("SELinux:  policy capability %s=%d\n",
2042 			selinux_policycap_names[i],
2043 			ebitmap_get_bit(&p->policycaps, i));
2044 
2045 	ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2046 		if (i >= ARRAY_SIZE(selinux_policycap_names))
2047 			pr_info("SELinux:  unknown policy capability %u\n",
2048 				i);
2049 	}
2050 }
2051 
2052 static int security_preserve_bools(struct selinux_state *state,
2053 				   struct policydb *newpolicydb);
2054 
2055 /**
2056  * security_load_policy - Load a security policy configuration.
2057  * @data: binary policy data
2058  * @len: length of data in bytes
2059  *
2060  * Load a new set of security policy configuration data,
2061  * validate it and convert the SID table as necessary.
2062  * This function will flush the access vector cache after
2063  * loading the new policy.
2064  */
2065 int security_load_policy(struct selinux_state *state, void *data, size_t len)
2066 {
2067 	struct policydb *policydb;
2068 	struct sidtab *oldsidtab, *newsidtab;
2069 	struct policydb *oldpolicydb, *newpolicydb;
2070 	struct selinux_mapping *oldmapping;
2071 	struct selinux_map newmap;
2072 	struct sidtab_convert_params convert_params;
2073 	struct convert_context_args args;
2074 	u32 seqno;
2075 	int rc = 0;
2076 	struct policy_file file = { data, len }, *fp = &file;
2077 
2078 	oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL);
2079 	if (!oldpolicydb) {
2080 		rc = -ENOMEM;
2081 		goto out;
2082 	}
2083 	newpolicydb = oldpolicydb + 1;
2084 
2085 	policydb = &state->ss->policydb;
2086 
2087 	newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL);
2088 	if (!newsidtab) {
2089 		rc = -ENOMEM;
2090 		goto out;
2091 	}
2092 
2093 	if (!state->initialized) {
2094 		rc = policydb_read(policydb, fp);
2095 		if (rc) {
2096 			kfree(newsidtab);
2097 			goto out;
2098 		}
2099 
2100 		policydb->len = len;
2101 		rc = selinux_set_mapping(policydb, secclass_map,
2102 					 &state->ss->map);
2103 		if (rc) {
2104 			kfree(newsidtab);
2105 			policydb_destroy(policydb);
2106 			goto out;
2107 		}
2108 
2109 		rc = policydb_load_isids(policydb, newsidtab);
2110 		if (rc) {
2111 			kfree(newsidtab);
2112 			policydb_destroy(policydb);
2113 			goto out;
2114 		}
2115 
2116 		state->ss->sidtab = newsidtab;
2117 		security_load_policycaps(state);
2118 		state->initialized = 1;
2119 		seqno = ++state->ss->latest_granting;
2120 		selinux_complete_init();
2121 		avc_ss_reset(state->avc, seqno);
2122 		selnl_notify_policyload(seqno);
2123 		selinux_status_update_policyload(state, seqno);
2124 		selinux_netlbl_cache_invalidate();
2125 		selinux_xfrm_notify_policyload();
2126 		goto out;
2127 	}
2128 
2129 	rc = policydb_read(newpolicydb, fp);
2130 	if (rc) {
2131 		kfree(newsidtab);
2132 		goto out;
2133 	}
2134 
2135 	newpolicydb->len = len;
2136 	/* If switching between different policy types, log MLS status */
2137 	if (policydb->mls_enabled && !newpolicydb->mls_enabled)
2138 		pr_info("SELinux: Disabling MLS support...\n");
2139 	else if (!policydb->mls_enabled && newpolicydb->mls_enabled)
2140 		pr_info("SELinux: Enabling MLS support...\n");
2141 
2142 	rc = policydb_load_isids(newpolicydb, newsidtab);
2143 	if (rc) {
2144 		pr_err("SELinux:  unable to load the initial SIDs\n");
2145 		policydb_destroy(newpolicydb);
2146 		kfree(newsidtab);
2147 		goto out;
2148 	}
2149 
2150 	rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap);
2151 	if (rc)
2152 		goto err;
2153 
2154 	rc = security_preserve_bools(state, newpolicydb);
2155 	if (rc) {
2156 		pr_err("SELinux:  unable to preserve booleans\n");
2157 		goto err;
2158 	}
2159 
2160 	oldsidtab = state->ss->sidtab;
2161 
2162 	/*
2163 	 * Convert the internal representations of contexts
2164 	 * in the new SID table.
2165 	 */
2166 	args.state = state;
2167 	args.oldp = policydb;
2168 	args.newp = newpolicydb;
2169 
2170 	convert_params.func = convert_context;
2171 	convert_params.args = &args;
2172 	convert_params.target = newsidtab;
2173 
2174 	rc = sidtab_convert(oldsidtab, &convert_params);
2175 	if (rc) {
2176 		pr_err("SELinux:  unable to convert the internal"
2177 			" representation of contexts in the new SID"
2178 			" table\n");
2179 		goto err;
2180 	}
2181 
2182 	/* Save the old policydb and SID table to free later. */
2183 	memcpy(oldpolicydb, policydb, sizeof(*policydb));
2184 
2185 	/* Install the new policydb and SID table. */
2186 	write_lock_irq(&state->ss->policy_rwlock);
2187 	memcpy(policydb, newpolicydb, sizeof(*policydb));
2188 	state->ss->sidtab = newsidtab;
2189 	security_load_policycaps(state);
2190 	oldmapping = state->ss->map.mapping;
2191 	state->ss->map.mapping = newmap.mapping;
2192 	state->ss->map.size = newmap.size;
2193 	seqno = ++state->ss->latest_granting;
2194 	write_unlock_irq(&state->ss->policy_rwlock);
2195 
2196 	/* Free the old policydb and SID table. */
2197 	policydb_destroy(oldpolicydb);
2198 	sidtab_destroy(oldsidtab);
2199 	kfree(oldsidtab);
2200 	kfree(oldmapping);
2201 
2202 	avc_ss_reset(state->avc, seqno);
2203 	selnl_notify_policyload(seqno);
2204 	selinux_status_update_policyload(state, seqno);
2205 	selinux_netlbl_cache_invalidate();
2206 	selinux_xfrm_notify_policyload();
2207 
2208 	rc = 0;
2209 	goto out;
2210 
2211 err:
2212 	kfree(newmap.mapping);
2213 	sidtab_destroy(newsidtab);
2214 	kfree(newsidtab);
2215 	policydb_destroy(newpolicydb);
2216 
2217 out:
2218 	kfree(oldpolicydb);
2219 	return rc;
2220 }
2221 
2222 size_t security_policydb_len(struct selinux_state *state)
2223 {
2224 	struct policydb *p = &state->ss->policydb;
2225 	size_t len;
2226 
2227 	read_lock(&state->ss->policy_rwlock);
2228 	len = p->len;
2229 	read_unlock(&state->ss->policy_rwlock);
2230 
2231 	return len;
2232 }
2233 
2234 /**
2235  * security_port_sid - Obtain the SID for a port.
2236  * @protocol: protocol number
2237  * @port: port number
2238  * @out_sid: security identifier
2239  */
2240 int security_port_sid(struct selinux_state *state,
2241 		      u8 protocol, u16 port, u32 *out_sid)
2242 {
2243 	struct policydb *policydb;
2244 	struct sidtab *sidtab;
2245 	struct ocontext *c;
2246 	int rc = 0;
2247 
2248 	read_lock(&state->ss->policy_rwlock);
2249 
2250 	policydb = &state->ss->policydb;
2251 	sidtab = state->ss->sidtab;
2252 
2253 	c = policydb->ocontexts[OCON_PORT];
2254 	while (c) {
2255 		if (c->u.port.protocol == protocol &&
2256 		    c->u.port.low_port <= port &&
2257 		    c->u.port.high_port >= port)
2258 			break;
2259 		c = c->next;
2260 	}
2261 
2262 	if (c) {
2263 		if (!c->sid[0]) {
2264 			rc = sidtab_context_to_sid(sidtab,
2265 						   &c->context[0],
2266 						   &c->sid[0]);
2267 			if (rc)
2268 				goto out;
2269 		}
2270 		*out_sid = c->sid[0];
2271 	} else {
2272 		*out_sid = SECINITSID_PORT;
2273 	}
2274 
2275 out:
2276 	read_unlock(&state->ss->policy_rwlock);
2277 	return rc;
2278 }
2279 
2280 /**
2281  * security_pkey_sid - Obtain the SID for a pkey.
2282  * @subnet_prefix: Subnet Prefix
2283  * @pkey_num: pkey number
2284  * @out_sid: security identifier
2285  */
2286 int security_ib_pkey_sid(struct selinux_state *state,
2287 			 u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2288 {
2289 	struct policydb *policydb;
2290 	struct sidtab *sidtab;
2291 	struct ocontext *c;
2292 	int rc = 0;
2293 
2294 	read_lock(&state->ss->policy_rwlock);
2295 
2296 	policydb = &state->ss->policydb;
2297 	sidtab = state->ss->sidtab;
2298 
2299 	c = policydb->ocontexts[OCON_IBPKEY];
2300 	while (c) {
2301 		if (c->u.ibpkey.low_pkey <= pkey_num &&
2302 		    c->u.ibpkey.high_pkey >= pkey_num &&
2303 		    c->u.ibpkey.subnet_prefix == subnet_prefix)
2304 			break;
2305 
2306 		c = c->next;
2307 	}
2308 
2309 	if (c) {
2310 		if (!c->sid[0]) {
2311 			rc = sidtab_context_to_sid(sidtab,
2312 						   &c->context[0],
2313 						   &c->sid[0]);
2314 			if (rc)
2315 				goto out;
2316 		}
2317 		*out_sid = c->sid[0];
2318 	} else
2319 		*out_sid = SECINITSID_UNLABELED;
2320 
2321 out:
2322 	read_unlock(&state->ss->policy_rwlock);
2323 	return rc;
2324 }
2325 
2326 /**
2327  * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2328  * @dev_name: device name
2329  * @port: port number
2330  * @out_sid: security identifier
2331  */
2332 int security_ib_endport_sid(struct selinux_state *state,
2333 			    const char *dev_name, u8 port_num, u32 *out_sid)
2334 {
2335 	struct policydb *policydb;
2336 	struct sidtab *sidtab;
2337 	struct ocontext *c;
2338 	int rc = 0;
2339 
2340 	read_lock(&state->ss->policy_rwlock);
2341 
2342 	policydb = &state->ss->policydb;
2343 	sidtab = state->ss->sidtab;
2344 
2345 	c = policydb->ocontexts[OCON_IBENDPORT];
2346 	while (c) {
2347 		if (c->u.ibendport.port == port_num &&
2348 		    !strncmp(c->u.ibendport.dev_name,
2349 			     dev_name,
2350 			     IB_DEVICE_NAME_MAX))
2351 			break;
2352 
2353 		c = c->next;
2354 	}
2355 
2356 	if (c) {
2357 		if (!c->sid[0]) {
2358 			rc = sidtab_context_to_sid(sidtab,
2359 						   &c->context[0],
2360 						   &c->sid[0]);
2361 			if (rc)
2362 				goto out;
2363 		}
2364 		*out_sid = c->sid[0];
2365 	} else
2366 		*out_sid = SECINITSID_UNLABELED;
2367 
2368 out:
2369 	read_unlock(&state->ss->policy_rwlock);
2370 	return rc;
2371 }
2372 
2373 /**
2374  * security_netif_sid - Obtain the SID for a network interface.
2375  * @name: interface name
2376  * @if_sid: interface SID
2377  */
2378 int security_netif_sid(struct selinux_state *state,
2379 		       char *name, u32 *if_sid)
2380 {
2381 	struct policydb *policydb;
2382 	struct sidtab *sidtab;
2383 	int rc = 0;
2384 	struct ocontext *c;
2385 
2386 	read_lock(&state->ss->policy_rwlock);
2387 
2388 	policydb = &state->ss->policydb;
2389 	sidtab = state->ss->sidtab;
2390 
2391 	c = policydb->ocontexts[OCON_NETIF];
2392 	while (c) {
2393 		if (strcmp(name, c->u.name) == 0)
2394 			break;
2395 		c = c->next;
2396 	}
2397 
2398 	if (c) {
2399 		if (!c->sid[0] || !c->sid[1]) {
2400 			rc = sidtab_context_to_sid(sidtab,
2401 						  &c->context[0],
2402 						  &c->sid[0]);
2403 			if (rc)
2404 				goto out;
2405 			rc = sidtab_context_to_sid(sidtab,
2406 						   &c->context[1],
2407 						   &c->sid[1]);
2408 			if (rc)
2409 				goto out;
2410 		}
2411 		*if_sid = c->sid[0];
2412 	} else
2413 		*if_sid = SECINITSID_NETIF;
2414 
2415 out:
2416 	read_unlock(&state->ss->policy_rwlock);
2417 	return rc;
2418 }
2419 
2420 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2421 {
2422 	int i, fail = 0;
2423 
2424 	for (i = 0; i < 4; i++)
2425 		if (addr[i] != (input[i] & mask[i])) {
2426 			fail = 1;
2427 			break;
2428 		}
2429 
2430 	return !fail;
2431 }
2432 
2433 /**
2434  * security_node_sid - Obtain the SID for a node (host).
2435  * @domain: communication domain aka address family
2436  * @addrp: address
2437  * @addrlen: address length in bytes
2438  * @out_sid: security identifier
2439  */
2440 int security_node_sid(struct selinux_state *state,
2441 		      u16 domain,
2442 		      void *addrp,
2443 		      u32 addrlen,
2444 		      u32 *out_sid)
2445 {
2446 	struct policydb *policydb;
2447 	struct sidtab *sidtab;
2448 	int rc;
2449 	struct ocontext *c;
2450 
2451 	read_lock(&state->ss->policy_rwlock);
2452 
2453 	policydb = &state->ss->policydb;
2454 	sidtab = state->ss->sidtab;
2455 
2456 	switch (domain) {
2457 	case AF_INET: {
2458 		u32 addr;
2459 
2460 		rc = -EINVAL;
2461 		if (addrlen != sizeof(u32))
2462 			goto out;
2463 
2464 		addr = *((u32 *)addrp);
2465 
2466 		c = policydb->ocontexts[OCON_NODE];
2467 		while (c) {
2468 			if (c->u.node.addr == (addr & c->u.node.mask))
2469 				break;
2470 			c = c->next;
2471 		}
2472 		break;
2473 	}
2474 
2475 	case AF_INET6:
2476 		rc = -EINVAL;
2477 		if (addrlen != sizeof(u64) * 2)
2478 			goto out;
2479 		c = policydb->ocontexts[OCON_NODE6];
2480 		while (c) {
2481 			if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2482 						c->u.node6.mask))
2483 				break;
2484 			c = c->next;
2485 		}
2486 		break;
2487 
2488 	default:
2489 		rc = 0;
2490 		*out_sid = SECINITSID_NODE;
2491 		goto out;
2492 	}
2493 
2494 	if (c) {
2495 		if (!c->sid[0]) {
2496 			rc = sidtab_context_to_sid(sidtab,
2497 						   &c->context[0],
2498 						   &c->sid[0]);
2499 			if (rc)
2500 				goto out;
2501 		}
2502 		*out_sid = c->sid[0];
2503 	} else {
2504 		*out_sid = SECINITSID_NODE;
2505 	}
2506 
2507 	rc = 0;
2508 out:
2509 	read_unlock(&state->ss->policy_rwlock);
2510 	return rc;
2511 }
2512 
2513 #define SIDS_NEL 25
2514 
2515 /**
2516  * security_get_user_sids - Obtain reachable SIDs for a user.
2517  * @fromsid: starting SID
2518  * @username: username
2519  * @sids: array of reachable SIDs for user
2520  * @nel: number of elements in @sids
2521  *
2522  * Generate the set of SIDs for legal security contexts
2523  * for a given user that can be reached by @fromsid.
2524  * Set *@sids to point to a dynamically allocated
2525  * array containing the set of SIDs.  Set *@nel to the
2526  * number of elements in the array.
2527  */
2528 
2529 int security_get_user_sids(struct selinux_state *state,
2530 			   u32 fromsid,
2531 			   char *username,
2532 			   u32 **sids,
2533 			   u32 *nel)
2534 {
2535 	struct policydb *policydb;
2536 	struct sidtab *sidtab;
2537 	struct context *fromcon, usercon;
2538 	u32 *mysids = NULL, *mysids2, sid;
2539 	u32 mynel = 0, maxnel = SIDS_NEL;
2540 	struct user_datum *user;
2541 	struct role_datum *role;
2542 	struct ebitmap_node *rnode, *tnode;
2543 	int rc = 0, i, j;
2544 
2545 	*sids = NULL;
2546 	*nel = 0;
2547 
2548 	if (!state->initialized)
2549 		goto out;
2550 
2551 	read_lock(&state->ss->policy_rwlock);
2552 
2553 	policydb = &state->ss->policydb;
2554 	sidtab = state->ss->sidtab;
2555 
2556 	context_init(&usercon);
2557 
2558 	rc = -EINVAL;
2559 	fromcon = sidtab_search(sidtab, fromsid);
2560 	if (!fromcon)
2561 		goto out_unlock;
2562 
2563 	rc = -EINVAL;
2564 	user = hashtab_search(policydb->p_users.table, username);
2565 	if (!user)
2566 		goto out_unlock;
2567 
2568 	usercon.user = user->value;
2569 
2570 	rc = -ENOMEM;
2571 	mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2572 	if (!mysids)
2573 		goto out_unlock;
2574 
2575 	ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2576 		role = policydb->role_val_to_struct[i];
2577 		usercon.role = i + 1;
2578 		ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2579 			usercon.type = j + 1;
2580 
2581 			if (mls_setup_user_range(policydb, fromcon, user,
2582 						 &usercon))
2583 				continue;
2584 
2585 			rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2586 			if (rc)
2587 				goto out_unlock;
2588 			if (mynel < maxnel) {
2589 				mysids[mynel++] = sid;
2590 			} else {
2591 				rc = -ENOMEM;
2592 				maxnel += SIDS_NEL;
2593 				mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2594 				if (!mysids2)
2595 					goto out_unlock;
2596 				memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2597 				kfree(mysids);
2598 				mysids = mysids2;
2599 				mysids[mynel++] = sid;
2600 			}
2601 		}
2602 	}
2603 	rc = 0;
2604 out_unlock:
2605 	read_unlock(&state->ss->policy_rwlock);
2606 	if (rc || !mynel) {
2607 		kfree(mysids);
2608 		goto out;
2609 	}
2610 
2611 	rc = -ENOMEM;
2612 	mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2613 	if (!mysids2) {
2614 		kfree(mysids);
2615 		goto out;
2616 	}
2617 	for (i = 0, j = 0; i < mynel; i++) {
2618 		struct av_decision dummy_avd;
2619 		rc = avc_has_perm_noaudit(state,
2620 					  fromsid, mysids[i],
2621 					  SECCLASS_PROCESS, /* kernel value */
2622 					  PROCESS__TRANSITION, AVC_STRICT,
2623 					  &dummy_avd);
2624 		if (!rc)
2625 			mysids2[j++] = mysids[i];
2626 		cond_resched();
2627 	}
2628 	rc = 0;
2629 	kfree(mysids);
2630 	*sids = mysids2;
2631 	*nel = j;
2632 out:
2633 	return rc;
2634 }
2635 
2636 /**
2637  * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2638  * @fstype: filesystem type
2639  * @path: path from root of mount
2640  * @sclass: file security class
2641  * @sid: SID for path
2642  *
2643  * Obtain a SID to use for a file in a filesystem that
2644  * cannot support xattr or use a fixed labeling behavior like
2645  * transition SIDs or task SIDs.
2646  *
2647  * The caller must acquire the policy_rwlock before calling this function.
2648  */
2649 static inline int __security_genfs_sid(struct selinux_state *state,
2650 				       const char *fstype,
2651 				       char *path,
2652 				       u16 orig_sclass,
2653 				       u32 *sid)
2654 {
2655 	struct policydb *policydb = &state->ss->policydb;
2656 	struct sidtab *sidtab = state->ss->sidtab;
2657 	int len;
2658 	u16 sclass;
2659 	struct genfs *genfs;
2660 	struct ocontext *c;
2661 	int rc, cmp = 0;
2662 
2663 	while (path[0] == '/' && path[1] == '/')
2664 		path++;
2665 
2666 	sclass = unmap_class(&state->ss->map, orig_sclass);
2667 	*sid = SECINITSID_UNLABELED;
2668 
2669 	for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2670 		cmp = strcmp(fstype, genfs->fstype);
2671 		if (cmp <= 0)
2672 			break;
2673 	}
2674 
2675 	rc = -ENOENT;
2676 	if (!genfs || cmp)
2677 		goto out;
2678 
2679 	for (c = genfs->head; c; c = c->next) {
2680 		len = strlen(c->u.name);
2681 		if ((!c->v.sclass || sclass == c->v.sclass) &&
2682 		    (strncmp(c->u.name, path, len) == 0))
2683 			break;
2684 	}
2685 
2686 	rc = -ENOENT;
2687 	if (!c)
2688 		goto out;
2689 
2690 	if (!c->sid[0]) {
2691 		rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]);
2692 		if (rc)
2693 			goto out;
2694 	}
2695 
2696 	*sid = c->sid[0];
2697 	rc = 0;
2698 out:
2699 	return rc;
2700 }
2701 
2702 /**
2703  * security_genfs_sid - Obtain a SID for a file in a filesystem
2704  * @fstype: filesystem type
2705  * @path: path from root of mount
2706  * @sclass: file security class
2707  * @sid: SID for path
2708  *
2709  * Acquire policy_rwlock before calling __security_genfs_sid() and release
2710  * it afterward.
2711  */
2712 int security_genfs_sid(struct selinux_state *state,
2713 		       const char *fstype,
2714 		       char *path,
2715 		       u16 orig_sclass,
2716 		       u32 *sid)
2717 {
2718 	int retval;
2719 
2720 	read_lock(&state->ss->policy_rwlock);
2721 	retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid);
2722 	read_unlock(&state->ss->policy_rwlock);
2723 	return retval;
2724 }
2725 
2726 /**
2727  * security_fs_use - Determine how to handle labeling for a filesystem.
2728  * @sb: superblock in question
2729  */
2730 int security_fs_use(struct selinux_state *state, struct super_block *sb)
2731 {
2732 	struct policydb *policydb;
2733 	struct sidtab *sidtab;
2734 	int rc = 0;
2735 	struct ocontext *c;
2736 	struct superblock_security_struct *sbsec = sb->s_security;
2737 	const char *fstype = sb->s_type->name;
2738 
2739 	read_lock(&state->ss->policy_rwlock);
2740 
2741 	policydb = &state->ss->policydb;
2742 	sidtab = state->ss->sidtab;
2743 
2744 	c = policydb->ocontexts[OCON_FSUSE];
2745 	while (c) {
2746 		if (strcmp(fstype, c->u.name) == 0)
2747 			break;
2748 		c = c->next;
2749 	}
2750 
2751 	if (c) {
2752 		sbsec->behavior = c->v.behavior;
2753 		if (!c->sid[0]) {
2754 			rc = sidtab_context_to_sid(sidtab, &c->context[0],
2755 						   &c->sid[0]);
2756 			if (rc)
2757 				goto out;
2758 		}
2759 		sbsec->sid = c->sid[0];
2760 	} else {
2761 		rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR,
2762 					  &sbsec->sid);
2763 		if (rc) {
2764 			sbsec->behavior = SECURITY_FS_USE_NONE;
2765 			rc = 0;
2766 		} else {
2767 			sbsec->behavior = SECURITY_FS_USE_GENFS;
2768 		}
2769 	}
2770 
2771 out:
2772 	read_unlock(&state->ss->policy_rwlock);
2773 	return rc;
2774 }
2775 
2776 int security_get_bools(struct selinux_state *state,
2777 		       int *len, char ***names, int **values)
2778 {
2779 	struct policydb *policydb;
2780 	int i, rc;
2781 
2782 	if (!state->initialized) {
2783 		*len = 0;
2784 		*names = NULL;
2785 		*values = NULL;
2786 		return 0;
2787 	}
2788 
2789 	read_lock(&state->ss->policy_rwlock);
2790 
2791 	policydb = &state->ss->policydb;
2792 
2793 	*names = NULL;
2794 	*values = NULL;
2795 
2796 	rc = 0;
2797 	*len = policydb->p_bools.nprim;
2798 	if (!*len)
2799 		goto out;
2800 
2801 	rc = -ENOMEM;
2802 	*names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2803 	if (!*names)
2804 		goto err;
2805 
2806 	rc = -ENOMEM;
2807 	*values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2808 	if (!*values)
2809 		goto err;
2810 
2811 	for (i = 0; i < *len; i++) {
2812 		(*values)[i] = policydb->bool_val_to_struct[i]->state;
2813 
2814 		rc = -ENOMEM;
2815 		(*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
2816 				      GFP_ATOMIC);
2817 		if (!(*names)[i])
2818 			goto err;
2819 	}
2820 	rc = 0;
2821 out:
2822 	read_unlock(&state->ss->policy_rwlock);
2823 	return rc;
2824 err:
2825 	if (*names) {
2826 		for (i = 0; i < *len; i++)
2827 			kfree((*names)[i]);
2828 	}
2829 	kfree(*values);
2830 	goto out;
2831 }
2832 
2833 
2834 int security_set_bools(struct selinux_state *state, int len, int *values)
2835 {
2836 	struct policydb *policydb;
2837 	int i, rc;
2838 	int lenp, seqno = 0;
2839 	struct cond_node *cur;
2840 
2841 	write_lock_irq(&state->ss->policy_rwlock);
2842 
2843 	policydb = &state->ss->policydb;
2844 
2845 	rc = -EFAULT;
2846 	lenp = policydb->p_bools.nprim;
2847 	if (len != lenp)
2848 		goto out;
2849 
2850 	for (i = 0; i < len; i++) {
2851 		if (!!values[i] != policydb->bool_val_to_struct[i]->state) {
2852 			audit_log(audit_context(), GFP_ATOMIC,
2853 				AUDIT_MAC_CONFIG_CHANGE,
2854 				"bool=%s val=%d old_val=%d auid=%u ses=%u",
2855 				sym_name(policydb, SYM_BOOLS, i),
2856 				!!values[i],
2857 				policydb->bool_val_to_struct[i]->state,
2858 				from_kuid(&init_user_ns, audit_get_loginuid(current)),
2859 				audit_get_sessionid(current));
2860 		}
2861 		if (values[i])
2862 			policydb->bool_val_to_struct[i]->state = 1;
2863 		else
2864 			policydb->bool_val_to_struct[i]->state = 0;
2865 	}
2866 
2867 	for (cur = policydb->cond_list; cur; cur = cur->next) {
2868 		rc = evaluate_cond_node(policydb, cur);
2869 		if (rc)
2870 			goto out;
2871 	}
2872 
2873 	seqno = ++state->ss->latest_granting;
2874 	rc = 0;
2875 out:
2876 	write_unlock_irq(&state->ss->policy_rwlock);
2877 	if (!rc) {
2878 		avc_ss_reset(state->avc, seqno);
2879 		selnl_notify_policyload(seqno);
2880 		selinux_status_update_policyload(state, seqno);
2881 		selinux_xfrm_notify_policyload();
2882 	}
2883 	return rc;
2884 }
2885 
2886 int security_get_bool_value(struct selinux_state *state,
2887 			    int index)
2888 {
2889 	struct policydb *policydb;
2890 	int rc;
2891 	int len;
2892 
2893 	read_lock(&state->ss->policy_rwlock);
2894 
2895 	policydb = &state->ss->policydb;
2896 
2897 	rc = -EFAULT;
2898 	len = policydb->p_bools.nprim;
2899 	if (index >= len)
2900 		goto out;
2901 
2902 	rc = policydb->bool_val_to_struct[index]->state;
2903 out:
2904 	read_unlock(&state->ss->policy_rwlock);
2905 	return rc;
2906 }
2907 
2908 static int security_preserve_bools(struct selinux_state *state,
2909 				   struct policydb *policydb)
2910 {
2911 	int rc, nbools = 0, *bvalues = NULL, i;
2912 	char **bnames = NULL;
2913 	struct cond_bool_datum *booldatum;
2914 	struct cond_node *cur;
2915 
2916 	rc = security_get_bools(state, &nbools, &bnames, &bvalues);
2917 	if (rc)
2918 		goto out;
2919 	for (i = 0; i < nbools; i++) {
2920 		booldatum = hashtab_search(policydb->p_bools.table, bnames[i]);
2921 		if (booldatum)
2922 			booldatum->state = bvalues[i];
2923 	}
2924 	for (cur = policydb->cond_list; cur; cur = cur->next) {
2925 		rc = evaluate_cond_node(policydb, cur);
2926 		if (rc)
2927 			goto out;
2928 	}
2929 
2930 out:
2931 	if (bnames) {
2932 		for (i = 0; i < nbools; i++)
2933 			kfree(bnames[i]);
2934 	}
2935 	kfree(bnames);
2936 	kfree(bvalues);
2937 	return rc;
2938 }
2939 
2940 /*
2941  * security_sid_mls_copy() - computes a new sid based on the given
2942  * sid and the mls portion of mls_sid.
2943  */
2944 int security_sid_mls_copy(struct selinux_state *state,
2945 			  u32 sid, u32 mls_sid, u32 *new_sid)
2946 {
2947 	struct policydb *policydb = &state->ss->policydb;
2948 	struct sidtab *sidtab = state->ss->sidtab;
2949 	struct context *context1;
2950 	struct context *context2;
2951 	struct context newcon;
2952 	char *s;
2953 	u32 len;
2954 	int rc;
2955 
2956 	rc = 0;
2957 	if (!state->initialized || !policydb->mls_enabled) {
2958 		*new_sid = sid;
2959 		goto out;
2960 	}
2961 
2962 	context_init(&newcon);
2963 
2964 	read_lock(&state->ss->policy_rwlock);
2965 
2966 	rc = -EINVAL;
2967 	context1 = sidtab_search(sidtab, sid);
2968 	if (!context1) {
2969 		pr_err("SELinux: %s:  unrecognized SID %d\n",
2970 			__func__, sid);
2971 		goto out_unlock;
2972 	}
2973 
2974 	rc = -EINVAL;
2975 	context2 = sidtab_search(sidtab, mls_sid);
2976 	if (!context2) {
2977 		pr_err("SELinux: %s:  unrecognized SID %d\n",
2978 			__func__, mls_sid);
2979 		goto out_unlock;
2980 	}
2981 
2982 	newcon.user = context1->user;
2983 	newcon.role = context1->role;
2984 	newcon.type = context1->type;
2985 	rc = mls_context_cpy(&newcon, context2);
2986 	if (rc)
2987 		goto out_unlock;
2988 
2989 	/* Check the validity of the new context. */
2990 	if (!policydb_context_isvalid(policydb, &newcon)) {
2991 		rc = convert_context_handle_invalid_context(state, &newcon);
2992 		if (rc) {
2993 			if (!context_struct_to_string(policydb, &newcon, &s,
2994 						      &len)) {
2995 				audit_log(audit_context(),
2996 					  GFP_ATOMIC, AUDIT_SELINUX_ERR,
2997 					  "op=security_sid_mls_copy "
2998 					  "invalid_context=%s", s);
2999 				kfree(s);
3000 			}
3001 			goto out_unlock;
3002 		}
3003 	}
3004 
3005 	rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3006 out_unlock:
3007 	read_unlock(&state->ss->policy_rwlock);
3008 	context_destroy(&newcon);
3009 out:
3010 	return rc;
3011 }
3012 
3013 /**
3014  * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3015  * @nlbl_sid: NetLabel SID
3016  * @nlbl_type: NetLabel labeling protocol type
3017  * @xfrm_sid: XFRM SID
3018  *
3019  * Description:
3020  * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3021  * resolved into a single SID it is returned via @peer_sid and the function
3022  * returns zero.  Otherwise @peer_sid is set to SECSID_NULL and the function
3023  * returns a negative value.  A table summarizing the behavior is below:
3024  *
3025  *                                 | function return |      @sid
3026  *   ------------------------------+-----------------+-----------------
3027  *   no peer labels                |        0        |    SECSID_NULL
3028  *   single peer label             |        0        |    <peer_label>
3029  *   multiple, consistent labels   |        0        |    <peer_label>
3030  *   multiple, inconsistent labels |    -<errno>     |    SECSID_NULL
3031  *
3032  */
3033 int security_net_peersid_resolve(struct selinux_state *state,
3034 				 u32 nlbl_sid, u32 nlbl_type,
3035 				 u32 xfrm_sid,
3036 				 u32 *peer_sid)
3037 {
3038 	struct policydb *policydb = &state->ss->policydb;
3039 	struct sidtab *sidtab = state->ss->sidtab;
3040 	int rc;
3041 	struct context *nlbl_ctx;
3042 	struct context *xfrm_ctx;
3043 
3044 	*peer_sid = SECSID_NULL;
3045 
3046 	/* handle the common (which also happens to be the set of easy) cases
3047 	 * right away, these two if statements catch everything involving a
3048 	 * single or absent peer SID/label */
3049 	if (xfrm_sid == SECSID_NULL) {
3050 		*peer_sid = nlbl_sid;
3051 		return 0;
3052 	}
3053 	/* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3054 	 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3055 	 * is present */
3056 	if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3057 		*peer_sid = xfrm_sid;
3058 		return 0;
3059 	}
3060 
3061 	/*
3062 	 * We don't need to check initialized here since the only way both
3063 	 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3064 	 * security server was initialized and state->initialized was true.
3065 	 */
3066 	if (!policydb->mls_enabled)
3067 		return 0;
3068 
3069 	read_lock(&state->ss->policy_rwlock);
3070 
3071 	rc = -EINVAL;
3072 	nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3073 	if (!nlbl_ctx) {
3074 		pr_err("SELinux: %s:  unrecognized SID %d\n",
3075 		       __func__, nlbl_sid);
3076 		goto out;
3077 	}
3078 	rc = -EINVAL;
3079 	xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3080 	if (!xfrm_ctx) {
3081 		pr_err("SELinux: %s:  unrecognized SID %d\n",
3082 		       __func__, xfrm_sid);
3083 		goto out;
3084 	}
3085 	rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3086 	if (rc)
3087 		goto out;
3088 
3089 	/* at present NetLabel SIDs/labels really only carry MLS
3090 	 * information so if the MLS portion of the NetLabel SID
3091 	 * matches the MLS portion of the labeled XFRM SID/label
3092 	 * then pass along the XFRM SID as it is the most
3093 	 * expressive */
3094 	*peer_sid = xfrm_sid;
3095 out:
3096 	read_unlock(&state->ss->policy_rwlock);
3097 	return rc;
3098 }
3099 
3100 static int get_classes_callback(void *k, void *d, void *args)
3101 {
3102 	struct class_datum *datum = d;
3103 	char *name = k, **classes = args;
3104 	int value = datum->value - 1;
3105 
3106 	classes[value] = kstrdup(name, GFP_ATOMIC);
3107 	if (!classes[value])
3108 		return -ENOMEM;
3109 
3110 	return 0;
3111 }
3112 
3113 int security_get_classes(struct selinux_state *state,
3114 			 char ***classes, int *nclasses)
3115 {
3116 	struct policydb *policydb = &state->ss->policydb;
3117 	int rc;
3118 
3119 	if (!state->initialized) {
3120 		*nclasses = 0;
3121 		*classes = NULL;
3122 		return 0;
3123 	}
3124 
3125 	read_lock(&state->ss->policy_rwlock);
3126 
3127 	rc = -ENOMEM;
3128 	*nclasses = policydb->p_classes.nprim;
3129 	*classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3130 	if (!*classes)
3131 		goto out;
3132 
3133 	rc = hashtab_map(policydb->p_classes.table, get_classes_callback,
3134 			*classes);
3135 	if (rc) {
3136 		int i;
3137 		for (i = 0; i < *nclasses; i++)
3138 			kfree((*classes)[i]);
3139 		kfree(*classes);
3140 	}
3141 
3142 out:
3143 	read_unlock(&state->ss->policy_rwlock);
3144 	return rc;
3145 }
3146 
3147 static int get_permissions_callback(void *k, void *d, void *args)
3148 {
3149 	struct perm_datum *datum = d;
3150 	char *name = k, **perms = args;
3151 	int value = datum->value - 1;
3152 
3153 	perms[value] = kstrdup(name, GFP_ATOMIC);
3154 	if (!perms[value])
3155 		return -ENOMEM;
3156 
3157 	return 0;
3158 }
3159 
3160 int security_get_permissions(struct selinux_state *state,
3161 			     char *class, char ***perms, int *nperms)
3162 {
3163 	struct policydb *policydb = &state->ss->policydb;
3164 	int rc, i;
3165 	struct class_datum *match;
3166 
3167 	read_lock(&state->ss->policy_rwlock);
3168 
3169 	rc = -EINVAL;
3170 	match = hashtab_search(policydb->p_classes.table, class);
3171 	if (!match) {
3172 		pr_err("SELinux: %s:  unrecognized class %s\n",
3173 			__func__, class);
3174 		goto out;
3175 	}
3176 
3177 	rc = -ENOMEM;
3178 	*nperms = match->permissions.nprim;
3179 	*perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3180 	if (!*perms)
3181 		goto out;
3182 
3183 	if (match->comdatum) {
3184 		rc = hashtab_map(match->comdatum->permissions.table,
3185 				get_permissions_callback, *perms);
3186 		if (rc)
3187 			goto err;
3188 	}
3189 
3190 	rc = hashtab_map(match->permissions.table, get_permissions_callback,
3191 			*perms);
3192 	if (rc)
3193 		goto err;
3194 
3195 out:
3196 	read_unlock(&state->ss->policy_rwlock);
3197 	return rc;
3198 
3199 err:
3200 	read_unlock(&state->ss->policy_rwlock);
3201 	for (i = 0; i < *nperms; i++)
3202 		kfree((*perms)[i]);
3203 	kfree(*perms);
3204 	return rc;
3205 }
3206 
3207 int security_get_reject_unknown(struct selinux_state *state)
3208 {
3209 	return state->ss->policydb.reject_unknown;
3210 }
3211 
3212 int security_get_allow_unknown(struct selinux_state *state)
3213 {
3214 	return state->ss->policydb.allow_unknown;
3215 }
3216 
3217 /**
3218  * security_policycap_supported - Check for a specific policy capability
3219  * @req_cap: capability
3220  *
3221  * Description:
3222  * This function queries the currently loaded policy to see if it supports the
3223  * capability specified by @req_cap.  Returns true (1) if the capability is
3224  * supported, false (0) if it isn't supported.
3225  *
3226  */
3227 int security_policycap_supported(struct selinux_state *state,
3228 				 unsigned int req_cap)
3229 {
3230 	struct policydb *policydb = &state->ss->policydb;
3231 	int rc;
3232 
3233 	read_lock(&state->ss->policy_rwlock);
3234 	rc = ebitmap_get_bit(&policydb->policycaps, req_cap);
3235 	read_unlock(&state->ss->policy_rwlock);
3236 
3237 	return rc;
3238 }
3239 
3240 struct selinux_audit_rule {
3241 	u32 au_seqno;
3242 	struct context au_ctxt;
3243 };
3244 
3245 void selinux_audit_rule_free(void *vrule)
3246 {
3247 	struct selinux_audit_rule *rule = vrule;
3248 
3249 	if (rule) {
3250 		context_destroy(&rule->au_ctxt);
3251 		kfree(rule);
3252 	}
3253 }
3254 
3255 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3256 {
3257 	struct selinux_state *state = &selinux_state;
3258 	struct policydb *policydb = &state->ss->policydb;
3259 	struct selinux_audit_rule *tmprule;
3260 	struct role_datum *roledatum;
3261 	struct type_datum *typedatum;
3262 	struct user_datum *userdatum;
3263 	struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3264 	int rc = 0;
3265 
3266 	*rule = NULL;
3267 
3268 	if (!state->initialized)
3269 		return -EOPNOTSUPP;
3270 
3271 	switch (field) {
3272 	case AUDIT_SUBJ_USER:
3273 	case AUDIT_SUBJ_ROLE:
3274 	case AUDIT_SUBJ_TYPE:
3275 	case AUDIT_OBJ_USER:
3276 	case AUDIT_OBJ_ROLE:
3277 	case AUDIT_OBJ_TYPE:
3278 		/* only 'equals' and 'not equals' fit user, role, and type */
3279 		if (op != Audit_equal && op != Audit_not_equal)
3280 			return -EINVAL;
3281 		break;
3282 	case AUDIT_SUBJ_SEN:
3283 	case AUDIT_SUBJ_CLR:
3284 	case AUDIT_OBJ_LEV_LOW:
3285 	case AUDIT_OBJ_LEV_HIGH:
3286 		/* we do not allow a range, indicated by the presence of '-' */
3287 		if (strchr(rulestr, '-'))
3288 			return -EINVAL;
3289 		break;
3290 	default:
3291 		/* only the above fields are valid */
3292 		return -EINVAL;
3293 	}
3294 
3295 	tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3296 	if (!tmprule)
3297 		return -ENOMEM;
3298 
3299 	context_init(&tmprule->au_ctxt);
3300 
3301 	read_lock(&state->ss->policy_rwlock);
3302 
3303 	tmprule->au_seqno = state->ss->latest_granting;
3304 
3305 	switch (field) {
3306 	case AUDIT_SUBJ_USER:
3307 	case AUDIT_OBJ_USER:
3308 		rc = -EINVAL;
3309 		userdatum = hashtab_search(policydb->p_users.table, rulestr);
3310 		if (!userdatum)
3311 			goto out;
3312 		tmprule->au_ctxt.user = userdatum->value;
3313 		break;
3314 	case AUDIT_SUBJ_ROLE:
3315 	case AUDIT_OBJ_ROLE:
3316 		rc = -EINVAL;
3317 		roledatum = hashtab_search(policydb->p_roles.table, rulestr);
3318 		if (!roledatum)
3319 			goto out;
3320 		tmprule->au_ctxt.role = roledatum->value;
3321 		break;
3322 	case AUDIT_SUBJ_TYPE:
3323 	case AUDIT_OBJ_TYPE:
3324 		rc = -EINVAL;
3325 		typedatum = hashtab_search(policydb->p_types.table, rulestr);
3326 		if (!typedatum)
3327 			goto out;
3328 		tmprule->au_ctxt.type = typedatum->value;
3329 		break;
3330 	case AUDIT_SUBJ_SEN:
3331 	case AUDIT_SUBJ_CLR:
3332 	case AUDIT_OBJ_LEV_LOW:
3333 	case AUDIT_OBJ_LEV_HIGH:
3334 		rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3335 				     GFP_ATOMIC);
3336 		if (rc)
3337 			goto out;
3338 		break;
3339 	}
3340 	rc = 0;
3341 out:
3342 	read_unlock(&state->ss->policy_rwlock);
3343 
3344 	if (rc) {
3345 		selinux_audit_rule_free(tmprule);
3346 		tmprule = NULL;
3347 	}
3348 
3349 	*rule = tmprule;
3350 
3351 	return rc;
3352 }
3353 
3354 /* Check to see if the rule contains any selinux fields */
3355 int selinux_audit_rule_known(struct audit_krule *rule)
3356 {
3357 	int i;
3358 
3359 	for (i = 0; i < rule->field_count; i++) {
3360 		struct audit_field *f = &rule->fields[i];
3361 		switch (f->type) {
3362 		case AUDIT_SUBJ_USER:
3363 		case AUDIT_SUBJ_ROLE:
3364 		case AUDIT_SUBJ_TYPE:
3365 		case AUDIT_SUBJ_SEN:
3366 		case AUDIT_SUBJ_CLR:
3367 		case AUDIT_OBJ_USER:
3368 		case AUDIT_OBJ_ROLE:
3369 		case AUDIT_OBJ_TYPE:
3370 		case AUDIT_OBJ_LEV_LOW:
3371 		case AUDIT_OBJ_LEV_HIGH:
3372 			return 1;
3373 		}
3374 	}
3375 
3376 	return 0;
3377 }
3378 
3379 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
3380 			     struct audit_context *actx)
3381 {
3382 	struct selinux_state *state = &selinux_state;
3383 	struct context *ctxt;
3384 	struct mls_level *level;
3385 	struct selinux_audit_rule *rule = vrule;
3386 	int match = 0;
3387 
3388 	if (unlikely(!rule)) {
3389 		WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3390 		return -ENOENT;
3391 	}
3392 
3393 	read_lock(&state->ss->policy_rwlock);
3394 
3395 	if (rule->au_seqno < state->ss->latest_granting) {
3396 		match = -ESTALE;
3397 		goto out;
3398 	}
3399 
3400 	ctxt = sidtab_search(state->ss->sidtab, sid);
3401 	if (unlikely(!ctxt)) {
3402 		WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3403 			  sid);
3404 		match = -ENOENT;
3405 		goto out;
3406 	}
3407 
3408 	/* a field/op pair that is not caught here will simply fall through
3409 	   without a match */
3410 	switch (field) {
3411 	case AUDIT_SUBJ_USER:
3412 	case AUDIT_OBJ_USER:
3413 		switch (op) {
3414 		case Audit_equal:
3415 			match = (ctxt->user == rule->au_ctxt.user);
3416 			break;
3417 		case Audit_not_equal:
3418 			match = (ctxt->user != rule->au_ctxt.user);
3419 			break;
3420 		}
3421 		break;
3422 	case AUDIT_SUBJ_ROLE:
3423 	case AUDIT_OBJ_ROLE:
3424 		switch (op) {
3425 		case Audit_equal:
3426 			match = (ctxt->role == rule->au_ctxt.role);
3427 			break;
3428 		case Audit_not_equal:
3429 			match = (ctxt->role != rule->au_ctxt.role);
3430 			break;
3431 		}
3432 		break;
3433 	case AUDIT_SUBJ_TYPE:
3434 	case AUDIT_OBJ_TYPE:
3435 		switch (op) {
3436 		case Audit_equal:
3437 			match = (ctxt->type == rule->au_ctxt.type);
3438 			break;
3439 		case Audit_not_equal:
3440 			match = (ctxt->type != rule->au_ctxt.type);
3441 			break;
3442 		}
3443 		break;
3444 	case AUDIT_SUBJ_SEN:
3445 	case AUDIT_SUBJ_CLR:
3446 	case AUDIT_OBJ_LEV_LOW:
3447 	case AUDIT_OBJ_LEV_HIGH:
3448 		level = ((field == AUDIT_SUBJ_SEN ||
3449 			  field == AUDIT_OBJ_LEV_LOW) ?
3450 			 &ctxt->range.level[0] : &ctxt->range.level[1]);
3451 		switch (op) {
3452 		case Audit_equal:
3453 			match = mls_level_eq(&rule->au_ctxt.range.level[0],
3454 					     level);
3455 			break;
3456 		case Audit_not_equal:
3457 			match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3458 					      level);
3459 			break;
3460 		case Audit_lt:
3461 			match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3462 					       level) &&
3463 				 !mls_level_eq(&rule->au_ctxt.range.level[0],
3464 					       level));
3465 			break;
3466 		case Audit_le:
3467 			match = mls_level_dom(&rule->au_ctxt.range.level[0],
3468 					      level);
3469 			break;
3470 		case Audit_gt:
3471 			match = (mls_level_dom(level,
3472 					      &rule->au_ctxt.range.level[0]) &&
3473 				 !mls_level_eq(level,
3474 					       &rule->au_ctxt.range.level[0]));
3475 			break;
3476 		case Audit_ge:
3477 			match = mls_level_dom(level,
3478 					      &rule->au_ctxt.range.level[0]);
3479 			break;
3480 		}
3481 	}
3482 
3483 out:
3484 	read_unlock(&state->ss->policy_rwlock);
3485 	return match;
3486 }
3487 
3488 static int (*aurule_callback)(void) = audit_update_lsm_rules;
3489 
3490 static int aurule_avc_callback(u32 event)
3491 {
3492 	int err = 0;
3493 
3494 	if (event == AVC_CALLBACK_RESET && aurule_callback)
3495 		err = aurule_callback();
3496 	return err;
3497 }
3498 
3499 static int __init aurule_init(void)
3500 {
3501 	int err;
3502 
3503 	err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3504 	if (err)
3505 		panic("avc_add_callback() failed, error %d\n", err);
3506 
3507 	return err;
3508 }
3509 __initcall(aurule_init);
3510 
3511 #ifdef CONFIG_NETLABEL
3512 /**
3513  * security_netlbl_cache_add - Add an entry to the NetLabel cache
3514  * @secattr: the NetLabel packet security attributes
3515  * @sid: the SELinux SID
3516  *
3517  * Description:
3518  * Attempt to cache the context in @ctx, which was derived from the packet in
3519  * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
3520  * already been initialized.
3521  *
3522  */
3523 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3524 				      u32 sid)
3525 {
3526 	u32 *sid_cache;
3527 
3528 	sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3529 	if (sid_cache == NULL)
3530 		return;
3531 	secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3532 	if (secattr->cache == NULL) {
3533 		kfree(sid_cache);
3534 		return;
3535 	}
3536 
3537 	*sid_cache = sid;
3538 	secattr->cache->free = kfree;
3539 	secattr->cache->data = sid_cache;
3540 	secattr->flags |= NETLBL_SECATTR_CACHE;
3541 }
3542 
3543 /**
3544  * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3545  * @secattr: the NetLabel packet security attributes
3546  * @sid: the SELinux SID
3547  *
3548  * Description:
3549  * Convert the given NetLabel security attributes in @secattr into a
3550  * SELinux SID.  If the @secattr field does not contain a full SELinux
3551  * SID/context then use SECINITSID_NETMSG as the foundation.  If possible the
3552  * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3553  * allow the @secattr to be used by NetLabel to cache the secattr to SID
3554  * conversion for future lookups.  Returns zero on success, negative values on
3555  * failure.
3556  *
3557  */
3558 int security_netlbl_secattr_to_sid(struct selinux_state *state,
3559 				   struct netlbl_lsm_secattr *secattr,
3560 				   u32 *sid)
3561 {
3562 	struct policydb *policydb = &state->ss->policydb;
3563 	struct sidtab *sidtab = state->ss->sidtab;
3564 	int rc;
3565 	struct context *ctx;
3566 	struct context ctx_new;
3567 
3568 	if (!state->initialized) {
3569 		*sid = SECSID_NULL;
3570 		return 0;
3571 	}
3572 
3573 	read_lock(&state->ss->policy_rwlock);
3574 
3575 	if (secattr->flags & NETLBL_SECATTR_CACHE)
3576 		*sid = *(u32 *)secattr->cache->data;
3577 	else if (secattr->flags & NETLBL_SECATTR_SECID)
3578 		*sid = secattr->attr.secid;
3579 	else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3580 		rc = -EIDRM;
3581 		ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3582 		if (ctx == NULL)
3583 			goto out;
3584 
3585 		context_init(&ctx_new);
3586 		ctx_new.user = ctx->user;
3587 		ctx_new.role = ctx->role;
3588 		ctx_new.type = ctx->type;
3589 		mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3590 		if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3591 			rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3592 			if (rc)
3593 				goto out;
3594 		}
3595 		rc = -EIDRM;
3596 		if (!mls_context_isvalid(policydb, &ctx_new))
3597 			goto out_free;
3598 
3599 		rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3600 		if (rc)
3601 			goto out_free;
3602 
3603 		security_netlbl_cache_add(secattr, *sid);
3604 
3605 		ebitmap_destroy(&ctx_new.range.level[0].cat);
3606 	} else
3607 		*sid = SECSID_NULL;
3608 
3609 	read_unlock(&state->ss->policy_rwlock);
3610 	return 0;
3611 out_free:
3612 	ebitmap_destroy(&ctx_new.range.level[0].cat);
3613 out:
3614 	read_unlock(&state->ss->policy_rwlock);
3615 	return rc;
3616 }
3617 
3618 /**
3619  * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3620  * @sid: the SELinux SID
3621  * @secattr: the NetLabel packet security attributes
3622  *
3623  * Description:
3624  * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3625  * Returns zero on success, negative values on failure.
3626  *
3627  */
3628 int security_netlbl_sid_to_secattr(struct selinux_state *state,
3629 				   u32 sid, struct netlbl_lsm_secattr *secattr)
3630 {
3631 	struct policydb *policydb = &state->ss->policydb;
3632 	int rc;
3633 	struct context *ctx;
3634 
3635 	if (!state->initialized)
3636 		return 0;
3637 
3638 	read_lock(&state->ss->policy_rwlock);
3639 
3640 	rc = -ENOENT;
3641 	ctx = sidtab_search(state->ss->sidtab, sid);
3642 	if (ctx == NULL)
3643 		goto out;
3644 
3645 	rc = -ENOMEM;
3646 	secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3647 				  GFP_ATOMIC);
3648 	if (secattr->domain == NULL)
3649 		goto out;
3650 
3651 	secattr->attr.secid = sid;
3652 	secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3653 	mls_export_netlbl_lvl(policydb, ctx, secattr);
3654 	rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3655 out:
3656 	read_unlock(&state->ss->policy_rwlock);
3657 	return rc;
3658 }
3659 #endif /* CONFIG_NETLABEL */
3660 
3661 /**
3662  * security_read_policy - read the policy.
3663  * @data: binary policy data
3664  * @len: length of data in bytes
3665  *
3666  */
3667 int security_read_policy(struct selinux_state *state,
3668 			 void **data, size_t *len)
3669 {
3670 	struct policydb *policydb = &state->ss->policydb;
3671 	int rc;
3672 	struct policy_file fp;
3673 
3674 	if (!state->initialized)
3675 		return -EINVAL;
3676 
3677 	*len = security_policydb_len(state);
3678 
3679 	*data = vmalloc_user(*len);
3680 	if (!*data)
3681 		return -ENOMEM;
3682 
3683 	fp.data = *data;
3684 	fp.len = *len;
3685 
3686 	read_lock(&state->ss->policy_rwlock);
3687 	rc = policydb_write(policydb, &fp);
3688 	read_unlock(&state->ss->policy_rwlock);
3689 
3690 	if (rc)
3691 		return rc;
3692 
3693 	*len = (unsigned long)fp.data - (unsigned long)*data;
3694 	return 0;
3695 
3696 }
3697