xref: /openbmc/linux/security/selinux/ss/services.c (revision 68198dca)
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 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 int selinux_policycap_netpeer;
84 int selinux_policycap_openperm;
85 int selinux_policycap_extsockclass;
86 int selinux_policycap_alwaysnetwork;
87 int selinux_policycap_cgroupseclabel;
88 int selinux_policycap_nnp_nosuid_transition;
89 
90 static DEFINE_RWLOCK(policy_rwlock);
91 
92 static struct sidtab sidtab;
93 struct policydb policydb;
94 int ss_initialized;
95 
96 /*
97  * The largest sequence number that has been used when
98  * providing an access decision to the access vector cache.
99  * The sequence number only changes when a policy change
100  * occurs.
101  */
102 static u32 latest_granting;
103 
104 /* Forward declaration. */
105 static int context_struct_to_string(struct context *context, char **scontext,
106 				    u32 *scontext_len);
107 
108 static void context_struct_compute_av(struct context *scontext,
109 					struct context *tcontext,
110 					u16 tclass,
111 					struct av_decision *avd,
112 					struct extended_perms *xperms);
113 
114 struct selinux_mapping {
115 	u16 value; /* policy value */
116 	unsigned num_perms;
117 	u32 perms[sizeof(u32) * 8];
118 };
119 
120 static struct selinux_mapping *current_mapping;
121 static u16 current_mapping_size;
122 
123 static int selinux_set_mapping(struct policydb *pol,
124 			       struct security_class_mapping *map,
125 			       struct selinux_mapping **out_map_p,
126 			       u16 *out_map_size)
127 {
128 	struct selinux_mapping *out_map = NULL;
129 	size_t size = sizeof(struct selinux_mapping);
130 	u16 i, j;
131 	unsigned k;
132 	bool print_unknown_handle = false;
133 
134 	/* Find number of classes in the input mapping */
135 	if (!map)
136 		return -EINVAL;
137 	i = 0;
138 	while (map[i].name)
139 		i++;
140 
141 	/* Allocate space for the class records, plus one for class zero */
142 	out_map = kcalloc(++i, size, GFP_ATOMIC);
143 	if (!out_map)
144 		return -ENOMEM;
145 
146 	/* Store the raw class and permission values */
147 	j = 0;
148 	while (map[j].name) {
149 		struct security_class_mapping *p_in = map + (j++);
150 		struct selinux_mapping *p_out = out_map + j;
151 
152 		/* An empty class string skips ahead */
153 		if (!strcmp(p_in->name, "")) {
154 			p_out->num_perms = 0;
155 			continue;
156 		}
157 
158 		p_out->value = string_to_security_class(pol, p_in->name);
159 		if (!p_out->value) {
160 			printk(KERN_INFO
161 			       "SELinux:  Class %s not defined in policy.\n",
162 			       p_in->name);
163 			if (pol->reject_unknown)
164 				goto err;
165 			p_out->num_perms = 0;
166 			print_unknown_handle = true;
167 			continue;
168 		}
169 
170 		k = 0;
171 		while (p_in->perms[k]) {
172 			/* An empty permission string skips ahead */
173 			if (!*p_in->perms[k]) {
174 				k++;
175 				continue;
176 			}
177 			p_out->perms[k] = string_to_av_perm(pol, p_out->value,
178 							    p_in->perms[k]);
179 			if (!p_out->perms[k]) {
180 				printk(KERN_INFO
181 				       "SELinux:  Permission %s in class %s not defined in policy.\n",
182 				       p_in->perms[k], p_in->name);
183 				if (pol->reject_unknown)
184 					goto err;
185 				print_unknown_handle = true;
186 			}
187 
188 			k++;
189 		}
190 		p_out->num_perms = k;
191 	}
192 
193 	if (print_unknown_handle)
194 		printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
195 		       pol->allow_unknown ? "allowed" : "denied");
196 
197 	*out_map_p = out_map;
198 	*out_map_size = i;
199 	return 0;
200 err:
201 	kfree(out_map);
202 	return -EINVAL;
203 }
204 
205 /*
206  * Get real, policy values from mapped values
207  */
208 
209 static u16 unmap_class(u16 tclass)
210 {
211 	if (tclass < current_mapping_size)
212 		return current_mapping[tclass].value;
213 
214 	return tclass;
215 }
216 
217 /*
218  * Get kernel value for class from its policy value
219  */
220 static u16 map_class(u16 pol_value)
221 {
222 	u16 i;
223 
224 	for (i = 1; i < current_mapping_size; i++) {
225 		if (current_mapping[i].value == pol_value)
226 			return i;
227 	}
228 
229 	return SECCLASS_NULL;
230 }
231 
232 static void map_decision(u16 tclass, struct av_decision *avd,
233 			 int allow_unknown)
234 {
235 	if (tclass < current_mapping_size) {
236 		unsigned i, n = current_mapping[tclass].num_perms;
237 		u32 result;
238 
239 		for (i = 0, result = 0; i < n; i++) {
240 			if (avd->allowed & current_mapping[tclass].perms[i])
241 				result |= 1<<i;
242 			if (allow_unknown && !current_mapping[tclass].perms[i])
243 				result |= 1<<i;
244 		}
245 		avd->allowed = result;
246 
247 		for (i = 0, result = 0; i < n; i++)
248 			if (avd->auditallow & current_mapping[tclass].perms[i])
249 				result |= 1<<i;
250 		avd->auditallow = result;
251 
252 		for (i = 0, result = 0; i < n; i++) {
253 			if (avd->auditdeny & current_mapping[tclass].perms[i])
254 				result |= 1<<i;
255 			if (!allow_unknown && !current_mapping[tclass].perms[i])
256 				result |= 1<<i;
257 		}
258 		/*
259 		 * In case the kernel has a bug and requests a permission
260 		 * between num_perms and the maximum permission number, we
261 		 * should audit that denial
262 		 */
263 		for (; i < (sizeof(u32)*8); i++)
264 			result |= 1<<i;
265 		avd->auditdeny = result;
266 	}
267 }
268 
269 int security_mls_enabled(void)
270 {
271 	return policydb.mls_enabled;
272 }
273 
274 /*
275  * Return the boolean value of a constraint expression
276  * when it is applied to the specified source and target
277  * security contexts.
278  *
279  * xcontext is a special beast...  It is used by the validatetrans rules
280  * only.  For these rules, scontext is the context before the transition,
281  * tcontext is the context after the transition, and xcontext is the context
282  * of the process performing the transition.  All other callers of
283  * constraint_expr_eval should pass in NULL for xcontext.
284  */
285 static int constraint_expr_eval(struct context *scontext,
286 				struct context *tcontext,
287 				struct context *xcontext,
288 				struct constraint_expr *cexpr)
289 {
290 	u32 val1, val2;
291 	struct context *c;
292 	struct role_datum *r1, *r2;
293 	struct mls_level *l1, *l2;
294 	struct constraint_expr *e;
295 	int s[CEXPR_MAXDEPTH];
296 	int sp = -1;
297 
298 	for (e = cexpr; e; e = e->next) {
299 		switch (e->expr_type) {
300 		case CEXPR_NOT:
301 			BUG_ON(sp < 0);
302 			s[sp] = !s[sp];
303 			break;
304 		case CEXPR_AND:
305 			BUG_ON(sp < 1);
306 			sp--;
307 			s[sp] &= s[sp + 1];
308 			break;
309 		case CEXPR_OR:
310 			BUG_ON(sp < 1);
311 			sp--;
312 			s[sp] |= s[sp + 1];
313 			break;
314 		case CEXPR_ATTR:
315 			if (sp == (CEXPR_MAXDEPTH - 1))
316 				return 0;
317 			switch (e->attr) {
318 			case CEXPR_USER:
319 				val1 = scontext->user;
320 				val2 = tcontext->user;
321 				break;
322 			case CEXPR_TYPE:
323 				val1 = scontext->type;
324 				val2 = tcontext->type;
325 				break;
326 			case CEXPR_ROLE:
327 				val1 = scontext->role;
328 				val2 = tcontext->role;
329 				r1 = policydb.role_val_to_struct[val1 - 1];
330 				r2 = policydb.role_val_to_struct[val2 - 1];
331 				switch (e->op) {
332 				case CEXPR_DOM:
333 					s[++sp] = ebitmap_get_bit(&r1->dominates,
334 								  val2 - 1);
335 					continue;
336 				case CEXPR_DOMBY:
337 					s[++sp] = ebitmap_get_bit(&r2->dominates,
338 								  val1 - 1);
339 					continue;
340 				case CEXPR_INCOMP:
341 					s[++sp] = (!ebitmap_get_bit(&r1->dominates,
342 								    val2 - 1) &&
343 						   !ebitmap_get_bit(&r2->dominates,
344 								    val1 - 1));
345 					continue;
346 				default:
347 					break;
348 				}
349 				break;
350 			case CEXPR_L1L2:
351 				l1 = &(scontext->range.level[0]);
352 				l2 = &(tcontext->range.level[0]);
353 				goto mls_ops;
354 			case CEXPR_L1H2:
355 				l1 = &(scontext->range.level[0]);
356 				l2 = &(tcontext->range.level[1]);
357 				goto mls_ops;
358 			case CEXPR_H1L2:
359 				l1 = &(scontext->range.level[1]);
360 				l2 = &(tcontext->range.level[0]);
361 				goto mls_ops;
362 			case CEXPR_H1H2:
363 				l1 = &(scontext->range.level[1]);
364 				l2 = &(tcontext->range.level[1]);
365 				goto mls_ops;
366 			case CEXPR_L1H1:
367 				l1 = &(scontext->range.level[0]);
368 				l2 = &(scontext->range.level[1]);
369 				goto mls_ops;
370 			case CEXPR_L2H2:
371 				l1 = &(tcontext->range.level[0]);
372 				l2 = &(tcontext->range.level[1]);
373 				goto mls_ops;
374 mls_ops:
375 			switch (e->op) {
376 			case CEXPR_EQ:
377 				s[++sp] = mls_level_eq(l1, l2);
378 				continue;
379 			case CEXPR_NEQ:
380 				s[++sp] = !mls_level_eq(l1, l2);
381 				continue;
382 			case CEXPR_DOM:
383 				s[++sp] = mls_level_dom(l1, l2);
384 				continue;
385 			case CEXPR_DOMBY:
386 				s[++sp] = mls_level_dom(l2, l1);
387 				continue;
388 			case CEXPR_INCOMP:
389 				s[++sp] = mls_level_incomp(l2, l1);
390 				continue;
391 			default:
392 				BUG();
393 				return 0;
394 			}
395 			break;
396 			default:
397 				BUG();
398 				return 0;
399 			}
400 
401 			switch (e->op) {
402 			case CEXPR_EQ:
403 				s[++sp] = (val1 == val2);
404 				break;
405 			case CEXPR_NEQ:
406 				s[++sp] = (val1 != val2);
407 				break;
408 			default:
409 				BUG();
410 				return 0;
411 			}
412 			break;
413 		case CEXPR_NAMES:
414 			if (sp == (CEXPR_MAXDEPTH-1))
415 				return 0;
416 			c = scontext;
417 			if (e->attr & CEXPR_TARGET)
418 				c = tcontext;
419 			else if (e->attr & CEXPR_XTARGET) {
420 				c = xcontext;
421 				if (!c) {
422 					BUG();
423 					return 0;
424 				}
425 			}
426 			if (e->attr & CEXPR_USER)
427 				val1 = c->user;
428 			else if (e->attr & CEXPR_ROLE)
429 				val1 = c->role;
430 			else if (e->attr & CEXPR_TYPE)
431 				val1 = c->type;
432 			else {
433 				BUG();
434 				return 0;
435 			}
436 
437 			switch (e->op) {
438 			case CEXPR_EQ:
439 				s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
440 				break;
441 			case CEXPR_NEQ:
442 				s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
443 				break;
444 			default:
445 				BUG();
446 				return 0;
447 			}
448 			break;
449 		default:
450 			BUG();
451 			return 0;
452 		}
453 	}
454 
455 	BUG_ON(sp != 0);
456 	return s[0];
457 }
458 
459 /*
460  * security_dump_masked_av - dumps masked permissions during
461  * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
462  */
463 static int dump_masked_av_helper(void *k, void *d, void *args)
464 {
465 	struct perm_datum *pdatum = d;
466 	char **permission_names = args;
467 
468 	BUG_ON(pdatum->value < 1 || pdatum->value > 32);
469 
470 	permission_names[pdatum->value - 1] = (char *)k;
471 
472 	return 0;
473 }
474 
475 static void security_dump_masked_av(struct context *scontext,
476 				    struct context *tcontext,
477 				    u16 tclass,
478 				    u32 permissions,
479 				    const char *reason)
480 {
481 	struct common_datum *common_dat;
482 	struct class_datum *tclass_dat;
483 	struct audit_buffer *ab;
484 	char *tclass_name;
485 	char *scontext_name = NULL;
486 	char *tcontext_name = NULL;
487 	char *permission_names[32];
488 	int index;
489 	u32 length;
490 	bool need_comma = false;
491 
492 	if (!permissions)
493 		return;
494 
495 	tclass_name = sym_name(&policydb, SYM_CLASSES, tclass - 1);
496 	tclass_dat = policydb.class_val_to_struct[tclass - 1];
497 	common_dat = tclass_dat->comdatum;
498 
499 	/* init permission_names */
500 	if (common_dat &&
501 	    hashtab_map(common_dat->permissions.table,
502 			dump_masked_av_helper, permission_names) < 0)
503 		goto out;
504 
505 	if (hashtab_map(tclass_dat->permissions.table,
506 			dump_masked_av_helper, permission_names) < 0)
507 		goto out;
508 
509 	/* get scontext/tcontext in text form */
510 	if (context_struct_to_string(scontext,
511 				     &scontext_name, &length) < 0)
512 		goto out;
513 
514 	if (context_struct_to_string(tcontext,
515 				     &tcontext_name, &length) < 0)
516 		goto out;
517 
518 	/* audit a message */
519 	ab = audit_log_start(current->audit_context,
520 			     GFP_ATOMIC, AUDIT_SELINUX_ERR);
521 	if (!ab)
522 		goto out;
523 
524 	audit_log_format(ab, "op=security_compute_av reason=%s "
525 			 "scontext=%s tcontext=%s tclass=%s perms=",
526 			 reason, scontext_name, tcontext_name, tclass_name);
527 
528 	for (index = 0; index < 32; index++) {
529 		u32 mask = (1 << index);
530 
531 		if ((mask & permissions) == 0)
532 			continue;
533 
534 		audit_log_format(ab, "%s%s",
535 				 need_comma ? "," : "",
536 				 permission_names[index]
537 				 ? permission_names[index] : "????");
538 		need_comma = true;
539 	}
540 	audit_log_end(ab);
541 out:
542 	/* release scontext/tcontext */
543 	kfree(tcontext_name);
544 	kfree(scontext_name);
545 
546 	return;
547 }
548 
549 /*
550  * security_boundary_permission - drops violated permissions
551  * on boundary constraint.
552  */
553 static void type_attribute_bounds_av(struct context *scontext,
554 				     struct context *tcontext,
555 				     u16 tclass,
556 				     struct av_decision *avd)
557 {
558 	struct context lo_scontext;
559 	struct context lo_tcontext, *tcontextp = tcontext;
560 	struct av_decision lo_avd;
561 	struct type_datum *source;
562 	struct type_datum *target;
563 	u32 masked = 0;
564 
565 	source = flex_array_get_ptr(policydb.type_val_to_struct_array,
566 				    scontext->type - 1);
567 	BUG_ON(!source);
568 
569 	if (!source->bounds)
570 		return;
571 
572 	target = flex_array_get_ptr(policydb.type_val_to_struct_array,
573 				    tcontext->type - 1);
574 	BUG_ON(!target);
575 
576 	memset(&lo_avd, 0, sizeof(lo_avd));
577 
578 	memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
579 	lo_scontext.type = source->bounds;
580 
581 	if (target->bounds) {
582 		memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
583 		lo_tcontext.type = target->bounds;
584 		tcontextp = &lo_tcontext;
585 	}
586 
587 	context_struct_compute_av(&lo_scontext,
588 				  tcontextp,
589 				  tclass,
590 				  &lo_avd,
591 				  NULL);
592 
593 	masked = ~lo_avd.allowed & avd->allowed;
594 
595 	if (likely(!masked))
596 		return;		/* no masked permission */
597 
598 	/* mask violated permissions */
599 	avd->allowed &= ~masked;
600 
601 	/* audit masked permissions */
602 	security_dump_masked_av(scontext, tcontext,
603 				tclass, masked, "bounds");
604 }
605 
606 /*
607  * flag which drivers have permissions
608  * only looking for ioctl based extended permssions
609  */
610 void services_compute_xperms_drivers(
611 		struct extended_perms *xperms,
612 		struct avtab_node *node)
613 {
614 	unsigned int i;
615 
616 	if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
617 		/* if one or more driver has all permissions allowed */
618 		for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
619 			xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
620 	} else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
621 		/* if allowing permissions within a driver */
622 		security_xperm_set(xperms->drivers.p,
623 					node->datum.u.xperms->driver);
624 	}
625 
626 	/* If no ioctl commands are allowed, ignore auditallow and auditdeny */
627 	if (node->key.specified & AVTAB_XPERMS_ALLOWED)
628 		xperms->len = 1;
629 }
630 
631 /*
632  * Compute access vectors and extended permissions based on a context
633  * structure pair for the permissions in a particular class.
634  */
635 static void context_struct_compute_av(struct context *scontext,
636 					struct context *tcontext,
637 					u16 tclass,
638 					struct av_decision *avd,
639 					struct extended_perms *xperms)
640 {
641 	struct constraint_node *constraint;
642 	struct role_allow *ra;
643 	struct avtab_key avkey;
644 	struct avtab_node *node;
645 	struct class_datum *tclass_datum;
646 	struct ebitmap *sattr, *tattr;
647 	struct ebitmap_node *snode, *tnode;
648 	unsigned int i, j;
649 
650 	avd->allowed = 0;
651 	avd->auditallow = 0;
652 	avd->auditdeny = 0xffffffff;
653 	if (xperms) {
654 		memset(&xperms->drivers, 0, sizeof(xperms->drivers));
655 		xperms->len = 0;
656 	}
657 
658 	if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
659 		if (printk_ratelimit())
660 			printk(KERN_WARNING "SELinux:  Invalid class %hu\n", tclass);
661 		return;
662 	}
663 
664 	tclass_datum = policydb.class_val_to_struct[tclass - 1];
665 
666 	/*
667 	 * If a specific type enforcement rule was defined for
668 	 * this permission check, then use it.
669 	 */
670 	avkey.target_class = tclass;
671 	avkey.specified = AVTAB_AV | AVTAB_XPERMS;
672 	sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1);
673 	BUG_ON(!sattr);
674 	tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1);
675 	BUG_ON(!tattr);
676 	ebitmap_for_each_positive_bit(sattr, snode, i) {
677 		ebitmap_for_each_positive_bit(tattr, tnode, j) {
678 			avkey.source_type = i + 1;
679 			avkey.target_type = j + 1;
680 			for (node = avtab_search_node(&policydb.te_avtab, &avkey);
681 			     node;
682 			     node = avtab_search_node_next(node, avkey.specified)) {
683 				if (node->key.specified == AVTAB_ALLOWED)
684 					avd->allowed |= node->datum.u.data;
685 				else if (node->key.specified == AVTAB_AUDITALLOW)
686 					avd->auditallow |= node->datum.u.data;
687 				else if (node->key.specified == AVTAB_AUDITDENY)
688 					avd->auditdeny &= node->datum.u.data;
689 				else if (xperms && (node->key.specified & AVTAB_XPERMS))
690 					services_compute_xperms_drivers(xperms, node);
691 			}
692 
693 			/* Check conditional av table for additional permissions */
694 			cond_compute_av(&policydb.te_cond_avtab, &avkey,
695 					avd, xperms);
696 
697 		}
698 	}
699 
700 	/*
701 	 * Remove any permissions prohibited by a constraint (this includes
702 	 * the MLS policy).
703 	 */
704 	constraint = tclass_datum->constraints;
705 	while (constraint) {
706 		if ((constraint->permissions & (avd->allowed)) &&
707 		    !constraint_expr_eval(scontext, tcontext, NULL,
708 					  constraint->expr)) {
709 			avd->allowed &= ~(constraint->permissions);
710 		}
711 		constraint = constraint->next;
712 	}
713 
714 	/*
715 	 * If checking process transition permission and the
716 	 * role is changing, then check the (current_role, new_role)
717 	 * pair.
718 	 */
719 	if (tclass == policydb.process_class &&
720 	    (avd->allowed & policydb.process_trans_perms) &&
721 	    scontext->role != tcontext->role) {
722 		for (ra = policydb.role_allow; ra; ra = ra->next) {
723 			if (scontext->role == ra->role &&
724 			    tcontext->role == ra->new_role)
725 				break;
726 		}
727 		if (!ra)
728 			avd->allowed &= ~policydb.process_trans_perms;
729 	}
730 
731 	/*
732 	 * If the given source and target types have boundary
733 	 * constraint, lazy checks have to mask any violated
734 	 * permission and notice it to userspace via audit.
735 	 */
736 	type_attribute_bounds_av(scontext, tcontext,
737 				 tclass, avd);
738 }
739 
740 static int security_validtrans_handle_fail(struct context *ocontext,
741 					   struct context *ncontext,
742 					   struct context *tcontext,
743 					   u16 tclass)
744 {
745 	char *o = NULL, *n = NULL, *t = NULL;
746 	u32 olen, nlen, tlen;
747 
748 	if (context_struct_to_string(ocontext, &o, &olen))
749 		goto out;
750 	if (context_struct_to_string(ncontext, &n, &nlen))
751 		goto out;
752 	if (context_struct_to_string(tcontext, &t, &tlen))
753 		goto out;
754 	audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
755 		  "op=security_validate_transition seresult=denied"
756 		  " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
757 		  o, n, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
758 out:
759 	kfree(o);
760 	kfree(n);
761 	kfree(t);
762 
763 	if (!selinux_enforcing)
764 		return 0;
765 	return -EPERM;
766 }
767 
768 static int security_compute_validatetrans(u32 oldsid, u32 newsid, u32 tasksid,
769 					  u16 orig_tclass, bool user)
770 {
771 	struct context *ocontext;
772 	struct context *ncontext;
773 	struct context *tcontext;
774 	struct class_datum *tclass_datum;
775 	struct constraint_node *constraint;
776 	u16 tclass;
777 	int rc = 0;
778 
779 	if (!ss_initialized)
780 		return 0;
781 
782 	read_lock(&policy_rwlock);
783 
784 	if (!user)
785 		tclass = unmap_class(orig_tclass);
786 	else
787 		tclass = orig_tclass;
788 
789 	if (!tclass || tclass > policydb.p_classes.nprim) {
790 		rc = -EINVAL;
791 		goto out;
792 	}
793 	tclass_datum = policydb.class_val_to_struct[tclass - 1];
794 
795 	ocontext = sidtab_search(&sidtab, oldsid);
796 	if (!ocontext) {
797 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
798 			__func__, oldsid);
799 		rc = -EINVAL;
800 		goto out;
801 	}
802 
803 	ncontext = sidtab_search(&sidtab, newsid);
804 	if (!ncontext) {
805 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
806 			__func__, newsid);
807 		rc = -EINVAL;
808 		goto out;
809 	}
810 
811 	tcontext = sidtab_search(&sidtab, tasksid);
812 	if (!tcontext) {
813 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
814 			__func__, tasksid);
815 		rc = -EINVAL;
816 		goto out;
817 	}
818 
819 	constraint = tclass_datum->validatetrans;
820 	while (constraint) {
821 		if (!constraint_expr_eval(ocontext, ncontext, tcontext,
822 					  constraint->expr)) {
823 			if (user)
824 				rc = -EPERM;
825 			else
826 				rc = security_validtrans_handle_fail(ocontext,
827 								     ncontext,
828 								     tcontext,
829 								     tclass);
830 			goto out;
831 		}
832 		constraint = constraint->next;
833 	}
834 
835 out:
836 	read_unlock(&policy_rwlock);
837 	return rc;
838 }
839 
840 int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid,
841 					u16 tclass)
842 {
843 	return security_compute_validatetrans(oldsid, newsid, tasksid,
844 						tclass, true);
845 }
846 
847 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
848 				 u16 orig_tclass)
849 {
850 	return security_compute_validatetrans(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(u32 old_sid, u32 new_sid)
864 {
865 	struct context *old_context, *new_context;
866 	struct type_datum *type;
867 	int index;
868 	int rc;
869 
870 	read_lock(&policy_rwlock);
871 
872 	rc = -EINVAL;
873 	old_context = sidtab_search(&sidtab, old_sid);
874 	if (!old_context) {
875 		printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
876 		       __func__, old_sid);
877 		goto out;
878 	}
879 
880 	rc = -EINVAL;
881 	new_context = sidtab_search(&sidtab, new_sid);
882 	if (!new_context) {
883 		printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
884 		       __func__, new_sid);
885 		goto out;
886 	}
887 
888 	rc = 0;
889 	/* type/domain unchanged */
890 	if (old_context->type == new_context->type)
891 		goto out;
892 
893 	index = new_context->type;
894 	while (true) {
895 		type = flex_array_get_ptr(policydb.type_val_to_struct_array,
896 					  index - 1);
897 		BUG_ON(!type);
898 
899 		/* not bounded anymore */
900 		rc = -EPERM;
901 		if (!type->bounds)
902 			break;
903 
904 		/* @newsid is bounded by @oldsid */
905 		rc = 0;
906 		if (type->bounds == old_context->type)
907 			break;
908 
909 		index = type->bounds;
910 	}
911 
912 	if (rc) {
913 		char *old_name = NULL;
914 		char *new_name = NULL;
915 		u32 length;
916 
917 		if (!context_struct_to_string(old_context,
918 					      &old_name, &length) &&
919 		    !context_struct_to_string(new_context,
920 					      &new_name, &length)) {
921 			audit_log(current->audit_context,
922 				  GFP_ATOMIC, AUDIT_SELINUX_ERR,
923 				  "op=security_bounded_transition "
924 				  "seresult=denied "
925 				  "oldcontext=%s newcontext=%s",
926 				  old_name, new_name);
927 		}
928 		kfree(new_name);
929 		kfree(old_name);
930 	}
931 out:
932 	read_unlock(&policy_rwlock);
933 
934 	return rc;
935 }
936 
937 static void avd_init(struct av_decision *avd)
938 {
939 	avd->allowed = 0;
940 	avd->auditallow = 0;
941 	avd->auditdeny = 0xffffffff;
942 	avd->seqno = latest_granting;
943 	avd->flags = 0;
944 }
945 
946 void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
947 					struct avtab_node *node)
948 {
949 	unsigned int i;
950 
951 	if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
952 		if (xpermd->driver != node->datum.u.xperms->driver)
953 			return;
954 	} else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
955 		if (!security_xperm_test(node->datum.u.xperms->perms.p,
956 					xpermd->driver))
957 			return;
958 	} else {
959 		BUG();
960 	}
961 
962 	if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
963 		xpermd->used |= XPERMS_ALLOWED;
964 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
965 			memset(xpermd->allowed->p, 0xff,
966 					sizeof(xpermd->allowed->p));
967 		}
968 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
969 			for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++)
970 				xpermd->allowed->p[i] |=
971 					node->datum.u.xperms->perms.p[i];
972 		}
973 	} else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
974 		xpermd->used |= XPERMS_AUDITALLOW;
975 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
976 			memset(xpermd->auditallow->p, 0xff,
977 					sizeof(xpermd->auditallow->p));
978 		}
979 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
980 			for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++)
981 				xpermd->auditallow->p[i] |=
982 					node->datum.u.xperms->perms.p[i];
983 		}
984 	} else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
985 		xpermd->used |= XPERMS_DONTAUDIT;
986 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
987 			memset(xpermd->dontaudit->p, 0xff,
988 					sizeof(xpermd->dontaudit->p));
989 		}
990 		if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
991 			for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++)
992 				xpermd->dontaudit->p[i] |=
993 					node->datum.u.xperms->perms.p[i];
994 		}
995 	} else {
996 		BUG();
997 	}
998 }
999 
1000 void security_compute_xperms_decision(u32 ssid,
1001 				u32 tsid,
1002 				u16 orig_tclass,
1003 				u8 driver,
1004 				struct extended_perms_decision *xpermd)
1005 {
1006 	u16 tclass;
1007 	struct context *scontext, *tcontext;
1008 	struct avtab_key avkey;
1009 	struct avtab_node *node;
1010 	struct ebitmap *sattr, *tattr;
1011 	struct ebitmap_node *snode, *tnode;
1012 	unsigned int i, j;
1013 
1014 	xpermd->driver = driver;
1015 	xpermd->used = 0;
1016 	memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1017 	memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1018 	memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1019 
1020 	read_lock(&policy_rwlock);
1021 	if (!ss_initialized)
1022 		goto allow;
1023 
1024 	scontext = sidtab_search(&sidtab, ssid);
1025 	if (!scontext) {
1026 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1027 		       __func__, ssid);
1028 		goto out;
1029 	}
1030 
1031 	tcontext = sidtab_search(&sidtab, tsid);
1032 	if (!tcontext) {
1033 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1034 		       __func__, tsid);
1035 		goto out;
1036 	}
1037 
1038 	tclass = unmap_class(orig_tclass);
1039 	if (unlikely(orig_tclass && !tclass)) {
1040 		if (policydb.allow_unknown)
1041 			goto allow;
1042 		goto out;
1043 	}
1044 
1045 
1046 	if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
1047 		pr_warn_ratelimited("SELinux:  Invalid class %hu\n", tclass);
1048 		goto out;
1049 	}
1050 
1051 	avkey.target_class = tclass;
1052 	avkey.specified = AVTAB_XPERMS;
1053 	sattr = flex_array_get(policydb.type_attr_map_array,
1054 				scontext->type - 1);
1055 	BUG_ON(!sattr);
1056 	tattr = flex_array_get(policydb.type_attr_map_array,
1057 				tcontext->type - 1);
1058 	BUG_ON(!tattr);
1059 	ebitmap_for_each_positive_bit(sattr, snode, i) {
1060 		ebitmap_for_each_positive_bit(tattr, tnode, j) {
1061 			avkey.source_type = i + 1;
1062 			avkey.target_type = j + 1;
1063 			for (node = avtab_search_node(&policydb.te_avtab, &avkey);
1064 			     node;
1065 			     node = avtab_search_node_next(node, avkey.specified))
1066 				services_compute_xperms_decision(xpermd, node);
1067 
1068 			cond_compute_xperms(&policydb.te_cond_avtab,
1069 						&avkey, xpermd);
1070 		}
1071 	}
1072 out:
1073 	read_unlock(&policy_rwlock);
1074 	return;
1075 allow:
1076 	memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1077 	goto out;
1078 }
1079 
1080 /**
1081  * security_compute_av - Compute access vector decisions.
1082  * @ssid: source security identifier
1083  * @tsid: target security identifier
1084  * @tclass: target security class
1085  * @avd: access vector decisions
1086  * @xperms: extended permissions
1087  *
1088  * Compute a set of access vector decisions based on the
1089  * SID pair (@ssid, @tsid) for the permissions in @tclass.
1090  */
1091 void security_compute_av(u32 ssid,
1092 			 u32 tsid,
1093 			 u16 orig_tclass,
1094 			 struct av_decision *avd,
1095 			 struct extended_perms *xperms)
1096 {
1097 	u16 tclass;
1098 	struct context *scontext = NULL, *tcontext = NULL;
1099 
1100 	read_lock(&policy_rwlock);
1101 	avd_init(avd);
1102 	xperms->len = 0;
1103 	if (!ss_initialized)
1104 		goto allow;
1105 
1106 	scontext = sidtab_search(&sidtab, ssid);
1107 	if (!scontext) {
1108 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1109 		       __func__, ssid);
1110 		goto out;
1111 	}
1112 
1113 	/* permissive domain? */
1114 	if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
1115 		avd->flags |= AVD_FLAGS_PERMISSIVE;
1116 
1117 	tcontext = sidtab_search(&sidtab, tsid);
1118 	if (!tcontext) {
1119 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1120 		       __func__, tsid);
1121 		goto out;
1122 	}
1123 
1124 	tclass = unmap_class(orig_tclass);
1125 	if (unlikely(orig_tclass && !tclass)) {
1126 		if (policydb.allow_unknown)
1127 			goto allow;
1128 		goto out;
1129 	}
1130 	context_struct_compute_av(scontext, tcontext, tclass, avd, xperms);
1131 	map_decision(orig_tclass, avd, policydb.allow_unknown);
1132 out:
1133 	read_unlock(&policy_rwlock);
1134 	return;
1135 allow:
1136 	avd->allowed = 0xffffffff;
1137 	goto out;
1138 }
1139 
1140 void security_compute_av_user(u32 ssid,
1141 			      u32 tsid,
1142 			      u16 tclass,
1143 			      struct av_decision *avd)
1144 {
1145 	struct context *scontext = NULL, *tcontext = NULL;
1146 
1147 	read_lock(&policy_rwlock);
1148 	avd_init(avd);
1149 	if (!ss_initialized)
1150 		goto allow;
1151 
1152 	scontext = sidtab_search(&sidtab, ssid);
1153 	if (!scontext) {
1154 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1155 		       __func__, ssid);
1156 		goto out;
1157 	}
1158 
1159 	/* permissive domain? */
1160 	if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
1161 		avd->flags |= AVD_FLAGS_PERMISSIVE;
1162 
1163 	tcontext = sidtab_search(&sidtab, tsid);
1164 	if (!tcontext) {
1165 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1166 		       __func__, tsid);
1167 		goto out;
1168 	}
1169 
1170 	if (unlikely(!tclass)) {
1171 		if (policydb.allow_unknown)
1172 			goto allow;
1173 		goto out;
1174 	}
1175 
1176 	context_struct_compute_av(scontext, tcontext, tclass, avd, NULL);
1177  out:
1178 	read_unlock(&policy_rwlock);
1179 	return;
1180 allow:
1181 	avd->allowed = 0xffffffff;
1182 	goto out;
1183 }
1184 
1185 /*
1186  * Write the security context string representation of
1187  * the context structure `context' into a dynamically
1188  * allocated string of the correct size.  Set `*scontext'
1189  * to point to this string and set `*scontext_len' to
1190  * the length of the string.
1191  */
1192 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
1193 {
1194 	char *scontextp;
1195 
1196 	if (scontext)
1197 		*scontext = NULL;
1198 	*scontext_len = 0;
1199 
1200 	if (context->len) {
1201 		*scontext_len = context->len;
1202 		if (scontext) {
1203 			*scontext = kstrdup(context->str, GFP_ATOMIC);
1204 			if (!(*scontext))
1205 				return -ENOMEM;
1206 		}
1207 		return 0;
1208 	}
1209 
1210 	/* Compute the size of the context. */
1211 	*scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1;
1212 	*scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1;
1213 	*scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1;
1214 	*scontext_len += mls_compute_context_len(context);
1215 
1216 	if (!scontext)
1217 		return 0;
1218 
1219 	/* Allocate space for the context; caller must free this space. */
1220 	scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1221 	if (!scontextp)
1222 		return -ENOMEM;
1223 	*scontext = scontextp;
1224 
1225 	/*
1226 	 * Copy the user name, role name and type name into the context.
1227 	 */
1228 	scontextp += sprintf(scontextp, "%s:%s:%s",
1229 		sym_name(&policydb, SYM_USERS, context->user - 1),
1230 		sym_name(&policydb, SYM_ROLES, context->role - 1),
1231 		sym_name(&policydb, SYM_TYPES, context->type - 1));
1232 
1233 	mls_sid_to_context(context, &scontextp);
1234 
1235 	*scontextp = 0;
1236 
1237 	return 0;
1238 }
1239 
1240 #include "initial_sid_to_string.h"
1241 
1242 const char *security_get_initial_sid_context(u32 sid)
1243 {
1244 	if (unlikely(sid > SECINITSID_NUM))
1245 		return NULL;
1246 	return initial_sid_to_string[sid];
1247 }
1248 
1249 static int security_sid_to_context_core(u32 sid, char **scontext,
1250 					u32 *scontext_len, int force)
1251 {
1252 	struct context *context;
1253 	int rc = 0;
1254 
1255 	if (scontext)
1256 		*scontext = NULL;
1257 	*scontext_len  = 0;
1258 
1259 	if (!ss_initialized) {
1260 		if (sid <= SECINITSID_NUM) {
1261 			char *scontextp;
1262 
1263 			*scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1264 			if (!scontext)
1265 				goto out;
1266 			scontextp = kmemdup(initial_sid_to_string[sid],
1267 					    *scontext_len, GFP_ATOMIC);
1268 			if (!scontextp) {
1269 				rc = -ENOMEM;
1270 				goto out;
1271 			}
1272 			*scontext = scontextp;
1273 			goto out;
1274 		}
1275 		printk(KERN_ERR "SELinux: %s:  called before initial "
1276 		       "load_policy on unknown SID %d\n", __func__, sid);
1277 		rc = -EINVAL;
1278 		goto out;
1279 	}
1280 	read_lock(&policy_rwlock);
1281 	if (force)
1282 		context = sidtab_search_force(&sidtab, sid);
1283 	else
1284 		context = sidtab_search(&sidtab, sid);
1285 	if (!context) {
1286 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1287 			__func__, sid);
1288 		rc = -EINVAL;
1289 		goto out_unlock;
1290 	}
1291 	rc = context_struct_to_string(context, scontext, scontext_len);
1292 out_unlock:
1293 	read_unlock(&policy_rwlock);
1294 out:
1295 	return rc;
1296 
1297 }
1298 
1299 /**
1300  * security_sid_to_context - Obtain a context for a given SID.
1301  * @sid: security identifier, SID
1302  * @scontext: security context
1303  * @scontext_len: length in bytes
1304  *
1305  * Write the string representation of the context associated with @sid
1306  * into a dynamically allocated string of the correct size.  Set @scontext
1307  * to point to this string and set @scontext_len to the length of the string.
1308  */
1309 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1310 {
1311 	return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1312 }
1313 
1314 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1315 {
1316 	return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1317 }
1318 
1319 /*
1320  * Caveat:  Mutates scontext.
1321  */
1322 static int string_to_context_struct(struct policydb *pol,
1323 				    struct sidtab *sidtabp,
1324 				    char *scontext,
1325 				    u32 scontext_len,
1326 				    struct context *ctx,
1327 				    u32 def_sid)
1328 {
1329 	struct role_datum *role;
1330 	struct type_datum *typdatum;
1331 	struct user_datum *usrdatum;
1332 	char *scontextp, *p, oldc;
1333 	int rc = 0;
1334 
1335 	context_init(ctx);
1336 
1337 	/* Parse the security context. */
1338 
1339 	rc = -EINVAL;
1340 	scontextp = (char *) scontext;
1341 
1342 	/* Extract the user. */
1343 	p = scontextp;
1344 	while (*p && *p != ':')
1345 		p++;
1346 
1347 	if (*p == 0)
1348 		goto out;
1349 
1350 	*p++ = 0;
1351 
1352 	usrdatum = hashtab_search(pol->p_users.table, scontextp);
1353 	if (!usrdatum)
1354 		goto out;
1355 
1356 	ctx->user = usrdatum->value;
1357 
1358 	/* Extract role. */
1359 	scontextp = p;
1360 	while (*p && *p != ':')
1361 		p++;
1362 
1363 	if (*p == 0)
1364 		goto out;
1365 
1366 	*p++ = 0;
1367 
1368 	role = hashtab_search(pol->p_roles.table, scontextp);
1369 	if (!role)
1370 		goto out;
1371 	ctx->role = role->value;
1372 
1373 	/* Extract type. */
1374 	scontextp = p;
1375 	while (*p && *p != ':')
1376 		p++;
1377 	oldc = *p;
1378 	*p++ = 0;
1379 
1380 	typdatum = hashtab_search(pol->p_types.table, scontextp);
1381 	if (!typdatum || typdatum->attribute)
1382 		goto out;
1383 
1384 	ctx->type = typdatum->value;
1385 
1386 	rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1387 	if (rc)
1388 		goto out;
1389 
1390 	rc = -EINVAL;
1391 	if ((p - scontext) < scontext_len)
1392 		goto out;
1393 
1394 	/* Check the validity of the new context. */
1395 	if (!policydb_context_isvalid(pol, ctx))
1396 		goto out;
1397 	rc = 0;
1398 out:
1399 	if (rc)
1400 		context_destroy(ctx);
1401 	return rc;
1402 }
1403 
1404 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1405 					u32 *sid, u32 def_sid, gfp_t gfp_flags,
1406 					int force)
1407 {
1408 	char *scontext2, *str = NULL;
1409 	struct context context;
1410 	int rc = 0;
1411 
1412 	/* An empty security context is never valid. */
1413 	if (!scontext_len)
1414 		return -EINVAL;
1415 
1416 	if (!ss_initialized) {
1417 		int i;
1418 
1419 		for (i = 1; i < SECINITSID_NUM; i++) {
1420 			if (!strcmp(initial_sid_to_string[i], scontext)) {
1421 				*sid = i;
1422 				return 0;
1423 			}
1424 		}
1425 		*sid = SECINITSID_KERNEL;
1426 		return 0;
1427 	}
1428 	*sid = SECSID_NULL;
1429 
1430 	/* Copy the string so that we can modify the copy as we parse it. */
1431 	scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1432 	if (!scontext2)
1433 		return -ENOMEM;
1434 	memcpy(scontext2, scontext, scontext_len);
1435 	scontext2[scontext_len] = 0;
1436 
1437 	if (force) {
1438 		/* Save another copy for storing in uninterpreted form */
1439 		rc = -ENOMEM;
1440 		str = kstrdup(scontext2, gfp_flags);
1441 		if (!str)
1442 			goto out;
1443 	}
1444 
1445 	read_lock(&policy_rwlock);
1446 	rc = string_to_context_struct(&policydb, &sidtab, scontext2,
1447 				      scontext_len, &context, def_sid);
1448 	if (rc == -EINVAL && force) {
1449 		context.str = str;
1450 		context.len = scontext_len;
1451 		str = NULL;
1452 	} else if (rc)
1453 		goto out_unlock;
1454 	rc = sidtab_context_to_sid(&sidtab, &context, sid);
1455 	context_destroy(&context);
1456 out_unlock:
1457 	read_unlock(&policy_rwlock);
1458 out:
1459 	kfree(scontext2);
1460 	kfree(str);
1461 	return rc;
1462 }
1463 
1464 /**
1465  * security_context_to_sid - Obtain a SID for a given security context.
1466  * @scontext: security context
1467  * @scontext_len: length in bytes
1468  * @sid: security identifier, SID
1469  * @gfp: context for the allocation
1470  *
1471  * Obtains a SID associated with the security context that
1472  * has the string representation specified by @scontext.
1473  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1474  * memory is available, or 0 on success.
1475  */
1476 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid,
1477 			    gfp_t gfp)
1478 {
1479 	return security_context_to_sid_core(scontext, scontext_len,
1480 					    sid, SECSID_NULL, gfp, 0);
1481 }
1482 
1483 int security_context_str_to_sid(const char *scontext, u32 *sid, gfp_t gfp)
1484 {
1485 	return security_context_to_sid(scontext, strlen(scontext), sid, gfp);
1486 }
1487 
1488 /**
1489  * security_context_to_sid_default - Obtain a SID for a given security context,
1490  * falling back to specified default if needed.
1491  *
1492  * @scontext: security context
1493  * @scontext_len: length in bytes
1494  * @sid: security identifier, SID
1495  * @def_sid: default SID to assign on error
1496  *
1497  * Obtains a SID associated with the security context that
1498  * has the string representation specified by @scontext.
1499  * The default SID is passed to the MLS layer to be used to allow
1500  * kernel labeling of the MLS field if the MLS field is not present
1501  * (for upgrading to MLS without full relabel).
1502  * Implicitly forces adding of the context even if it cannot be mapped yet.
1503  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1504  * memory is available, or 0 on success.
1505  */
1506 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1507 				    u32 *sid, u32 def_sid, gfp_t gfp_flags)
1508 {
1509 	return security_context_to_sid_core(scontext, scontext_len,
1510 					    sid, def_sid, gfp_flags, 1);
1511 }
1512 
1513 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1514 				  u32 *sid)
1515 {
1516 	return security_context_to_sid_core(scontext, scontext_len,
1517 					    sid, SECSID_NULL, GFP_KERNEL, 1);
1518 }
1519 
1520 static int compute_sid_handle_invalid_context(
1521 	struct context *scontext,
1522 	struct context *tcontext,
1523 	u16 tclass,
1524 	struct context *newcontext)
1525 {
1526 	char *s = NULL, *t = NULL, *n = NULL;
1527 	u32 slen, tlen, nlen;
1528 
1529 	if (context_struct_to_string(scontext, &s, &slen))
1530 		goto out;
1531 	if (context_struct_to_string(tcontext, &t, &tlen))
1532 		goto out;
1533 	if (context_struct_to_string(newcontext, &n, &nlen))
1534 		goto out;
1535 	audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1536 		  "op=security_compute_sid invalid_context=%s"
1537 		  " scontext=%s"
1538 		  " tcontext=%s"
1539 		  " tclass=%s",
1540 		  n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
1541 out:
1542 	kfree(s);
1543 	kfree(t);
1544 	kfree(n);
1545 	if (!selinux_enforcing)
1546 		return 0;
1547 	return -EACCES;
1548 }
1549 
1550 static void filename_compute_type(struct policydb *p, struct context *newcontext,
1551 				  u32 stype, u32 ttype, u16 tclass,
1552 				  const char *objname)
1553 {
1554 	struct filename_trans ft;
1555 	struct filename_trans_datum *otype;
1556 
1557 	/*
1558 	 * Most filename trans rules are going to live in specific directories
1559 	 * like /dev or /var/run.  This bitmap will quickly skip rule searches
1560 	 * if the ttype does not contain any rules.
1561 	 */
1562 	if (!ebitmap_get_bit(&p->filename_trans_ttypes, ttype))
1563 		return;
1564 
1565 	ft.stype = stype;
1566 	ft.ttype = ttype;
1567 	ft.tclass = tclass;
1568 	ft.name = objname;
1569 
1570 	otype = hashtab_search(p->filename_trans, &ft);
1571 	if (otype)
1572 		newcontext->type = otype->otype;
1573 }
1574 
1575 static int security_compute_sid(u32 ssid,
1576 				u32 tsid,
1577 				u16 orig_tclass,
1578 				u32 specified,
1579 				const char *objname,
1580 				u32 *out_sid,
1581 				bool kern)
1582 {
1583 	struct class_datum *cladatum = NULL;
1584 	struct context *scontext = NULL, *tcontext = NULL, newcontext;
1585 	struct role_trans *roletr = NULL;
1586 	struct avtab_key avkey;
1587 	struct avtab_datum *avdatum;
1588 	struct avtab_node *node;
1589 	u16 tclass;
1590 	int rc = 0;
1591 	bool sock;
1592 
1593 	if (!ss_initialized) {
1594 		switch (orig_tclass) {
1595 		case SECCLASS_PROCESS: /* kernel value */
1596 			*out_sid = ssid;
1597 			break;
1598 		default:
1599 			*out_sid = tsid;
1600 			break;
1601 		}
1602 		goto out;
1603 	}
1604 
1605 	context_init(&newcontext);
1606 
1607 	read_lock(&policy_rwlock);
1608 
1609 	if (kern) {
1610 		tclass = unmap_class(orig_tclass);
1611 		sock = security_is_socket_class(orig_tclass);
1612 	} else {
1613 		tclass = orig_tclass;
1614 		sock = security_is_socket_class(map_class(tclass));
1615 	}
1616 
1617 	scontext = sidtab_search(&sidtab, ssid);
1618 	if (!scontext) {
1619 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1620 		       __func__, ssid);
1621 		rc = -EINVAL;
1622 		goto out_unlock;
1623 	}
1624 	tcontext = sidtab_search(&sidtab, tsid);
1625 	if (!tcontext) {
1626 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1627 		       __func__, tsid);
1628 		rc = -EINVAL;
1629 		goto out_unlock;
1630 	}
1631 
1632 	if (tclass && tclass <= policydb.p_classes.nprim)
1633 		cladatum = policydb.class_val_to_struct[tclass - 1];
1634 
1635 	/* Set the user identity. */
1636 	switch (specified) {
1637 	case AVTAB_TRANSITION:
1638 	case AVTAB_CHANGE:
1639 		if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1640 			newcontext.user = tcontext->user;
1641 		} else {
1642 			/* notice this gets both DEFAULT_SOURCE and unset */
1643 			/* Use the process user identity. */
1644 			newcontext.user = scontext->user;
1645 		}
1646 		break;
1647 	case AVTAB_MEMBER:
1648 		/* Use the related object owner. */
1649 		newcontext.user = tcontext->user;
1650 		break;
1651 	}
1652 
1653 	/* Set the role to default values. */
1654 	if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1655 		newcontext.role = scontext->role;
1656 	} else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1657 		newcontext.role = tcontext->role;
1658 	} else {
1659 		if ((tclass == policydb.process_class) || (sock == true))
1660 			newcontext.role = scontext->role;
1661 		else
1662 			newcontext.role = OBJECT_R_VAL;
1663 	}
1664 
1665 	/* Set the type to default values. */
1666 	if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1667 		newcontext.type = scontext->type;
1668 	} else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1669 		newcontext.type = tcontext->type;
1670 	} else {
1671 		if ((tclass == policydb.process_class) || (sock == true)) {
1672 			/* Use the type of process. */
1673 			newcontext.type = scontext->type;
1674 		} else {
1675 			/* Use the type of the related object. */
1676 			newcontext.type = tcontext->type;
1677 		}
1678 	}
1679 
1680 	/* Look for a type transition/member/change rule. */
1681 	avkey.source_type = scontext->type;
1682 	avkey.target_type = tcontext->type;
1683 	avkey.target_class = tclass;
1684 	avkey.specified = specified;
1685 	avdatum = avtab_search(&policydb.te_avtab, &avkey);
1686 
1687 	/* If no permanent rule, also check for enabled conditional rules */
1688 	if (!avdatum) {
1689 		node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1690 		for (; node; node = avtab_search_node_next(node, specified)) {
1691 			if (node->key.specified & AVTAB_ENABLED) {
1692 				avdatum = &node->datum;
1693 				break;
1694 			}
1695 		}
1696 	}
1697 
1698 	if (avdatum) {
1699 		/* Use the type from the type transition/member/change rule. */
1700 		newcontext.type = avdatum->u.data;
1701 	}
1702 
1703 	/* if we have a objname this is a file trans check so check those rules */
1704 	if (objname)
1705 		filename_compute_type(&policydb, &newcontext, scontext->type,
1706 				      tcontext->type, tclass, objname);
1707 
1708 	/* Check for class-specific changes. */
1709 	if (specified & AVTAB_TRANSITION) {
1710 		/* Look for a role transition rule. */
1711 		for (roletr = policydb.role_tr; roletr; roletr = roletr->next) {
1712 			if ((roletr->role == scontext->role) &&
1713 			    (roletr->type == tcontext->type) &&
1714 			    (roletr->tclass == tclass)) {
1715 				/* Use the role transition rule. */
1716 				newcontext.role = roletr->new_role;
1717 				break;
1718 			}
1719 		}
1720 	}
1721 
1722 	/* Set the MLS attributes.
1723 	   This is done last because it may allocate memory. */
1724 	rc = mls_compute_sid(scontext, tcontext, tclass, specified,
1725 			     &newcontext, sock);
1726 	if (rc)
1727 		goto out_unlock;
1728 
1729 	/* Check the validity of the context. */
1730 	if (!policydb_context_isvalid(&policydb, &newcontext)) {
1731 		rc = compute_sid_handle_invalid_context(scontext,
1732 							tcontext,
1733 							tclass,
1734 							&newcontext);
1735 		if (rc)
1736 			goto out_unlock;
1737 	}
1738 	/* Obtain the sid for the context. */
1739 	rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1740 out_unlock:
1741 	read_unlock(&policy_rwlock);
1742 	context_destroy(&newcontext);
1743 out:
1744 	return rc;
1745 }
1746 
1747 /**
1748  * security_transition_sid - Compute the SID for a new subject/object.
1749  * @ssid: source security identifier
1750  * @tsid: target security identifier
1751  * @tclass: target security class
1752  * @out_sid: security identifier for new subject/object
1753  *
1754  * Compute a SID to use for labeling a new subject or object in the
1755  * class @tclass based on a SID pair (@ssid, @tsid).
1756  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1757  * if insufficient memory is available, or %0 if the new SID was
1758  * computed successfully.
1759  */
1760 int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1761 			    const struct qstr *qstr, u32 *out_sid)
1762 {
1763 	return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1764 				    qstr ? qstr->name : NULL, out_sid, true);
1765 }
1766 
1767 int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1768 				 const char *objname, u32 *out_sid)
1769 {
1770 	return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1771 				    objname, out_sid, false);
1772 }
1773 
1774 /**
1775  * security_member_sid - Compute the SID for member selection.
1776  * @ssid: source security identifier
1777  * @tsid: target security identifier
1778  * @tclass: target security class
1779  * @out_sid: security identifier for selected member
1780  *
1781  * Compute a SID to use when selecting a member of a polyinstantiated
1782  * object of class @tclass based on a SID pair (@ssid, @tsid).
1783  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1784  * if insufficient memory is available, or %0 if the SID was
1785  * computed successfully.
1786  */
1787 int security_member_sid(u32 ssid,
1788 			u32 tsid,
1789 			u16 tclass,
1790 			u32 *out_sid)
1791 {
1792 	return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL,
1793 				    out_sid, false);
1794 }
1795 
1796 /**
1797  * security_change_sid - Compute the SID for object relabeling.
1798  * @ssid: source security identifier
1799  * @tsid: target security identifier
1800  * @tclass: target security class
1801  * @out_sid: security identifier for selected member
1802  *
1803  * Compute a SID to use for relabeling an object of class @tclass
1804  * based on a SID pair (@ssid, @tsid).
1805  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1806  * if insufficient memory is available, or %0 if the SID was
1807  * computed successfully.
1808  */
1809 int security_change_sid(u32 ssid,
1810 			u32 tsid,
1811 			u16 tclass,
1812 			u32 *out_sid)
1813 {
1814 	return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1815 				    out_sid, false);
1816 }
1817 
1818 /* Clone the SID into the new SID table. */
1819 static int clone_sid(u32 sid,
1820 		     struct context *context,
1821 		     void *arg)
1822 {
1823 	struct sidtab *s = arg;
1824 
1825 	if (sid > SECINITSID_NUM)
1826 		return sidtab_insert(s, sid, context);
1827 	else
1828 		return 0;
1829 }
1830 
1831 static inline int convert_context_handle_invalid_context(struct context *context)
1832 {
1833 	char *s;
1834 	u32 len;
1835 
1836 	if (selinux_enforcing)
1837 		return -EINVAL;
1838 
1839 	if (!context_struct_to_string(context, &s, &len)) {
1840 		printk(KERN_WARNING "SELinux:  Context %s would be invalid if enforcing\n", s);
1841 		kfree(s);
1842 	}
1843 	return 0;
1844 }
1845 
1846 struct convert_context_args {
1847 	struct policydb *oldp;
1848 	struct policydb *newp;
1849 };
1850 
1851 /*
1852  * Convert the values in the security context
1853  * structure `c' from the values specified
1854  * in the policy `p->oldp' to the values specified
1855  * in the policy `p->newp'.  Verify that the
1856  * context is valid under the new policy.
1857  */
1858 static int convert_context(u32 key,
1859 			   struct context *c,
1860 			   void *p)
1861 {
1862 	struct convert_context_args *args;
1863 	struct context oldc;
1864 	struct ocontext *oc;
1865 	struct mls_range *range;
1866 	struct role_datum *role;
1867 	struct type_datum *typdatum;
1868 	struct user_datum *usrdatum;
1869 	char *s;
1870 	u32 len;
1871 	int rc = 0;
1872 
1873 	if (key <= SECINITSID_NUM)
1874 		goto out;
1875 
1876 	args = p;
1877 
1878 	if (c->str) {
1879 		struct context ctx;
1880 
1881 		rc = -ENOMEM;
1882 		s = kstrdup(c->str, GFP_KERNEL);
1883 		if (!s)
1884 			goto out;
1885 
1886 		rc = string_to_context_struct(args->newp, NULL, s,
1887 					      c->len, &ctx, SECSID_NULL);
1888 		kfree(s);
1889 		if (!rc) {
1890 			printk(KERN_INFO "SELinux:  Context %s became valid (mapped).\n",
1891 			       c->str);
1892 			/* Replace string with mapped representation. */
1893 			kfree(c->str);
1894 			memcpy(c, &ctx, sizeof(*c));
1895 			goto out;
1896 		} else if (rc == -EINVAL) {
1897 			/* Retain string representation for later mapping. */
1898 			rc = 0;
1899 			goto out;
1900 		} else {
1901 			/* Other error condition, e.g. ENOMEM. */
1902 			printk(KERN_ERR "SELinux:   Unable to map context %s, rc = %d.\n",
1903 			       c->str, -rc);
1904 			goto out;
1905 		}
1906 	}
1907 
1908 	rc = context_cpy(&oldc, c);
1909 	if (rc)
1910 		goto out;
1911 
1912 	/* Convert the user. */
1913 	rc = -EINVAL;
1914 	usrdatum = hashtab_search(args->newp->p_users.table,
1915 				  sym_name(args->oldp, SYM_USERS, c->user - 1));
1916 	if (!usrdatum)
1917 		goto bad;
1918 	c->user = usrdatum->value;
1919 
1920 	/* Convert the role. */
1921 	rc = -EINVAL;
1922 	role = hashtab_search(args->newp->p_roles.table,
1923 			      sym_name(args->oldp, SYM_ROLES, c->role - 1));
1924 	if (!role)
1925 		goto bad;
1926 	c->role = role->value;
1927 
1928 	/* Convert the type. */
1929 	rc = -EINVAL;
1930 	typdatum = hashtab_search(args->newp->p_types.table,
1931 				  sym_name(args->oldp, SYM_TYPES, c->type - 1));
1932 	if (!typdatum)
1933 		goto bad;
1934 	c->type = typdatum->value;
1935 
1936 	/* Convert the MLS fields if dealing with MLS policies */
1937 	if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1938 		rc = mls_convert_context(args->oldp, args->newp, c);
1939 		if (rc)
1940 			goto bad;
1941 	} else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1942 		/*
1943 		 * Switching between MLS and non-MLS policy:
1944 		 * free any storage used by the MLS fields in the
1945 		 * context for all existing entries in the sidtab.
1946 		 */
1947 		mls_context_destroy(c);
1948 	} else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1949 		/*
1950 		 * Switching between non-MLS and MLS policy:
1951 		 * ensure that the MLS fields of the context for all
1952 		 * existing entries in the sidtab are filled in with a
1953 		 * suitable default value, likely taken from one of the
1954 		 * initial SIDs.
1955 		 */
1956 		oc = args->newp->ocontexts[OCON_ISID];
1957 		while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1958 			oc = oc->next;
1959 		rc = -EINVAL;
1960 		if (!oc) {
1961 			printk(KERN_ERR "SELinux:  unable to look up"
1962 				" the initial SIDs list\n");
1963 			goto bad;
1964 		}
1965 		range = &oc->context[0].range;
1966 		rc = mls_range_set(c, range);
1967 		if (rc)
1968 			goto bad;
1969 	}
1970 
1971 	/* Check the validity of the new context. */
1972 	if (!policydb_context_isvalid(args->newp, c)) {
1973 		rc = convert_context_handle_invalid_context(&oldc);
1974 		if (rc)
1975 			goto bad;
1976 	}
1977 
1978 	context_destroy(&oldc);
1979 
1980 	rc = 0;
1981 out:
1982 	return rc;
1983 bad:
1984 	/* Map old representation to string and save it. */
1985 	rc = context_struct_to_string(&oldc, &s, &len);
1986 	if (rc)
1987 		return rc;
1988 	context_destroy(&oldc);
1989 	context_destroy(c);
1990 	c->str = s;
1991 	c->len = len;
1992 	printk(KERN_INFO "SELinux:  Context %s became invalid (unmapped).\n",
1993 	       c->str);
1994 	rc = 0;
1995 	goto out;
1996 }
1997 
1998 static void security_load_policycaps(void)
1999 {
2000 	unsigned int i;
2001 	struct ebitmap_node *node;
2002 
2003 	selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
2004 						  POLICYDB_CAPABILITY_NETPEER);
2005 	selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
2006 						  POLICYDB_CAPABILITY_OPENPERM);
2007 	selinux_policycap_extsockclass = ebitmap_get_bit(&policydb.policycaps,
2008 					  POLICYDB_CAPABILITY_EXTSOCKCLASS);
2009 	selinux_policycap_alwaysnetwork = ebitmap_get_bit(&policydb.policycaps,
2010 						  POLICYDB_CAPABILITY_ALWAYSNETWORK);
2011 	selinux_policycap_cgroupseclabel =
2012 		ebitmap_get_bit(&policydb.policycaps,
2013 				POLICYDB_CAPABILITY_CGROUPSECLABEL);
2014 	selinux_policycap_nnp_nosuid_transition =
2015 		ebitmap_get_bit(&policydb.policycaps,
2016 				POLICYDB_CAPABILITY_NNP_NOSUID_TRANSITION);
2017 
2018 	for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2019 		pr_info("SELinux:  policy capability %s=%d\n",
2020 			selinux_policycap_names[i],
2021 			ebitmap_get_bit(&policydb.policycaps, i));
2022 
2023 	ebitmap_for_each_positive_bit(&policydb.policycaps, node, i) {
2024 		if (i >= ARRAY_SIZE(selinux_policycap_names))
2025 			pr_info("SELinux:  unknown policy capability %u\n",
2026 				i);
2027 	}
2028 }
2029 
2030 static int security_preserve_bools(struct policydb *p);
2031 
2032 /**
2033  * security_load_policy - Load a security policy configuration.
2034  * @data: binary policy data
2035  * @len: length of data in bytes
2036  *
2037  * Load a new set of security policy configuration data,
2038  * validate it and convert the SID table as necessary.
2039  * This function will flush the access vector cache after
2040  * loading the new policy.
2041  */
2042 int security_load_policy(void *data, size_t len)
2043 {
2044 	struct policydb *oldpolicydb, *newpolicydb;
2045 	struct sidtab oldsidtab, newsidtab;
2046 	struct selinux_mapping *oldmap, *map = NULL;
2047 	struct convert_context_args args;
2048 	u32 seqno;
2049 	u16 map_size;
2050 	int rc = 0;
2051 	struct policy_file file = { data, len }, *fp = &file;
2052 
2053 	oldpolicydb = kzalloc(2 * sizeof(*oldpolicydb), GFP_KERNEL);
2054 	if (!oldpolicydb) {
2055 		rc = -ENOMEM;
2056 		goto out;
2057 	}
2058 	newpolicydb = oldpolicydb + 1;
2059 
2060 	if (!ss_initialized) {
2061 		avtab_cache_init();
2062 		ebitmap_cache_init();
2063 		hashtab_cache_init();
2064 		rc = policydb_read(&policydb, fp);
2065 		if (rc) {
2066 			avtab_cache_destroy();
2067 			ebitmap_cache_destroy();
2068 			hashtab_cache_destroy();
2069 			goto out;
2070 		}
2071 
2072 		policydb.len = len;
2073 		rc = selinux_set_mapping(&policydb, secclass_map,
2074 					 &current_mapping,
2075 					 &current_mapping_size);
2076 		if (rc) {
2077 			policydb_destroy(&policydb);
2078 			avtab_cache_destroy();
2079 			ebitmap_cache_destroy();
2080 			hashtab_cache_destroy();
2081 			goto out;
2082 		}
2083 
2084 		rc = policydb_load_isids(&policydb, &sidtab);
2085 		if (rc) {
2086 			policydb_destroy(&policydb);
2087 			avtab_cache_destroy();
2088 			ebitmap_cache_destroy();
2089 			hashtab_cache_destroy();
2090 			goto out;
2091 		}
2092 
2093 		security_load_policycaps();
2094 		ss_initialized = 1;
2095 		seqno = ++latest_granting;
2096 		selinux_complete_init();
2097 		avc_ss_reset(seqno);
2098 		selnl_notify_policyload(seqno);
2099 		selinux_status_update_policyload(seqno);
2100 		selinux_netlbl_cache_invalidate();
2101 		selinux_xfrm_notify_policyload();
2102 		goto out;
2103 	}
2104 
2105 #if 0
2106 	sidtab_hash_eval(&sidtab, "sids");
2107 #endif
2108 
2109 	rc = policydb_read(newpolicydb, fp);
2110 	if (rc)
2111 		goto out;
2112 
2113 	newpolicydb->len = len;
2114 	/* If switching between different policy types, log MLS status */
2115 	if (policydb.mls_enabled && !newpolicydb->mls_enabled)
2116 		printk(KERN_INFO "SELinux: Disabling MLS support...\n");
2117 	else if (!policydb.mls_enabled && newpolicydb->mls_enabled)
2118 		printk(KERN_INFO "SELinux: Enabling MLS support...\n");
2119 
2120 	rc = policydb_load_isids(newpolicydb, &newsidtab);
2121 	if (rc) {
2122 		printk(KERN_ERR "SELinux:  unable to load the initial SIDs\n");
2123 		policydb_destroy(newpolicydb);
2124 		goto out;
2125 	}
2126 
2127 	rc = selinux_set_mapping(newpolicydb, secclass_map, &map, &map_size);
2128 	if (rc)
2129 		goto err;
2130 
2131 	rc = security_preserve_bools(newpolicydb);
2132 	if (rc) {
2133 		printk(KERN_ERR "SELinux:  unable to preserve booleans\n");
2134 		goto err;
2135 	}
2136 
2137 	/* Clone the SID table. */
2138 	sidtab_shutdown(&sidtab);
2139 
2140 	rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
2141 	if (rc)
2142 		goto err;
2143 
2144 	/*
2145 	 * Convert the internal representations of contexts
2146 	 * in the new SID table.
2147 	 */
2148 	args.oldp = &policydb;
2149 	args.newp = newpolicydb;
2150 	rc = sidtab_map(&newsidtab, convert_context, &args);
2151 	if (rc) {
2152 		printk(KERN_ERR "SELinux:  unable to convert the internal"
2153 			" representation of contexts in the new SID"
2154 			" table\n");
2155 		goto err;
2156 	}
2157 
2158 	/* Save the old policydb and SID table to free later. */
2159 	memcpy(oldpolicydb, &policydb, sizeof(policydb));
2160 	sidtab_set(&oldsidtab, &sidtab);
2161 
2162 	/* Install the new policydb and SID table. */
2163 	write_lock_irq(&policy_rwlock);
2164 	memcpy(&policydb, newpolicydb, sizeof(policydb));
2165 	sidtab_set(&sidtab, &newsidtab);
2166 	security_load_policycaps();
2167 	oldmap = current_mapping;
2168 	current_mapping = map;
2169 	current_mapping_size = map_size;
2170 	seqno = ++latest_granting;
2171 	write_unlock_irq(&policy_rwlock);
2172 
2173 	/* Free the old policydb and SID table. */
2174 	policydb_destroy(oldpolicydb);
2175 	sidtab_destroy(&oldsidtab);
2176 	kfree(oldmap);
2177 
2178 	avc_ss_reset(seqno);
2179 	selnl_notify_policyload(seqno);
2180 	selinux_status_update_policyload(seqno);
2181 	selinux_netlbl_cache_invalidate();
2182 	selinux_xfrm_notify_policyload();
2183 
2184 	rc = 0;
2185 	goto out;
2186 
2187 err:
2188 	kfree(map);
2189 	sidtab_destroy(&newsidtab);
2190 	policydb_destroy(newpolicydb);
2191 
2192 out:
2193 	kfree(oldpolicydb);
2194 	return rc;
2195 }
2196 
2197 size_t security_policydb_len(void)
2198 {
2199 	size_t len;
2200 
2201 	read_lock(&policy_rwlock);
2202 	len = policydb.len;
2203 	read_unlock(&policy_rwlock);
2204 
2205 	return len;
2206 }
2207 
2208 /**
2209  * security_port_sid - Obtain the SID for a port.
2210  * @protocol: protocol number
2211  * @port: port number
2212  * @out_sid: security identifier
2213  */
2214 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
2215 {
2216 	struct ocontext *c;
2217 	int rc = 0;
2218 
2219 	read_lock(&policy_rwlock);
2220 
2221 	c = policydb.ocontexts[OCON_PORT];
2222 	while (c) {
2223 		if (c->u.port.protocol == protocol &&
2224 		    c->u.port.low_port <= port &&
2225 		    c->u.port.high_port >= port)
2226 			break;
2227 		c = c->next;
2228 	}
2229 
2230 	if (c) {
2231 		if (!c->sid[0]) {
2232 			rc = sidtab_context_to_sid(&sidtab,
2233 						   &c->context[0],
2234 						   &c->sid[0]);
2235 			if (rc)
2236 				goto out;
2237 		}
2238 		*out_sid = c->sid[0];
2239 	} else {
2240 		*out_sid = SECINITSID_PORT;
2241 	}
2242 
2243 out:
2244 	read_unlock(&policy_rwlock);
2245 	return rc;
2246 }
2247 
2248 /**
2249  * security_pkey_sid - Obtain the SID for a pkey.
2250  * @subnet_prefix: Subnet Prefix
2251  * @pkey_num: pkey number
2252  * @out_sid: security identifier
2253  */
2254 int security_ib_pkey_sid(u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2255 {
2256 	struct ocontext *c;
2257 	int rc = 0;
2258 
2259 	read_lock(&policy_rwlock);
2260 
2261 	c = policydb.ocontexts[OCON_IBPKEY];
2262 	while (c) {
2263 		if (c->u.ibpkey.low_pkey <= pkey_num &&
2264 		    c->u.ibpkey.high_pkey >= pkey_num &&
2265 		    c->u.ibpkey.subnet_prefix == subnet_prefix)
2266 			break;
2267 
2268 		c = c->next;
2269 	}
2270 
2271 	if (c) {
2272 		if (!c->sid[0]) {
2273 			rc = sidtab_context_to_sid(&sidtab,
2274 						   &c->context[0],
2275 						   &c->sid[0]);
2276 			if (rc)
2277 				goto out;
2278 		}
2279 		*out_sid = c->sid[0];
2280 	} else
2281 		*out_sid = SECINITSID_UNLABELED;
2282 
2283 out:
2284 	read_unlock(&policy_rwlock);
2285 	return rc;
2286 }
2287 
2288 /**
2289  * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2290  * @dev_name: device name
2291  * @port: port number
2292  * @out_sid: security identifier
2293  */
2294 int security_ib_endport_sid(const char *dev_name, u8 port_num, u32 *out_sid)
2295 {
2296 	struct ocontext *c;
2297 	int rc = 0;
2298 
2299 	read_lock(&policy_rwlock);
2300 
2301 	c = policydb.ocontexts[OCON_IBENDPORT];
2302 	while (c) {
2303 		if (c->u.ibendport.port == port_num &&
2304 		    !strncmp(c->u.ibendport.dev_name,
2305 			     dev_name,
2306 			     IB_DEVICE_NAME_MAX))
2307 			break;
2308 
2309 		c = c->next;
2310 	}
2311 
2312 	if (c) {
2313 		if (!c->sid[0]) {
2314 			rc = sidtab_context_to_sid(&sidtab,
2315 						   &c->context[0],
2316 						   &c->sid[0]);
2317 			if (rc)
2318 				goto out;
2319 		}
2320 		*out_sid = c->sid[0];
2321 	} else
2322 		*out_sid = SECINITSID_UNLABELED;
2323 
2324 out:
2325 	read_unlock(&policy_rwlock);
2326 	return rc;
2327 }
2328 
2329 /**
2330  * security_netif_sid - Obtain the SID for a network interface.
2331  * @name: interface name
2332  * @if_sid: interface SID
2333  */
2334 int security_netif_sid(char *name, u32 *if_sid)
2335 {
2336 	int rc = 0;
2337 	struct ocontext *c;
2338 
2339 	read_lock(&policy_rwlock);
2340 
2341 	c = policydb.ocontexts[OCON_NETIF];
2342 	while (c) {
2343 		if (strcmp(name, c->u.name) == 0)
2344 			break;
2345 		c = c->next;
2346 	}
2347 
2348 	if (c) {
2349 		if (!c->sid[0] || !c->sid[1]) {
2350 			rc = sidtab_context_to_sid(&sidtab,
2351 						  &c->context[0],
2352 						  &c->sid[0]);
2353 			if (rc)
2354 				goto out;
2355 			rc = sidtab_context_to_sid(&sidtab,
2356 						   &c->context[1],
2357 						   &c->sid[1]);
2358 			if (rc)
2359 				goto out;
2360 		}
2361 		*if_sid = c->sid[0];
2362 	} else
2363 		*if_sid = SECINITSID_NETIF;
2364 
2365 out:
2366 	read_unlock(&policy_rwlock);
2367 	return rc;
2368 }
2369 
2370 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2371 {
2372 	int i, fail = 0;
2373 
2374 	for (i = 0; i < 4; i++)
2375 		if (addr[i] != (input[i] & mask[i])) {
2376 			fail = 1;
2377 			break;
2378 		}
2379 
2380 	return !fail;
2381 }
2382 
2383 /**
2384  * security_node_sid - Obtain the SID for a node (host).
2385  * @domain: communication domain aka address family
2386  * @addrp: address
2387  * @addrlen: address length in bytes
2388  * @out_sid: security identifier
2389  */
2390 int security_node_sid(u16 domain,
2391 		      void *addrp,
2392 		      u32 addrlen,
2393 		      u32 *out_sid)
2394 {
2395 	int rc;
2396 	struct ocontext *c;
2397 
2398 	read_lock(&policy_rwlock);
2399 
2400 	switch (domain) {
2401 	case AF_INET: {
2402 		u32 addr;
2403 
2404 		rc = -EINVAL;
2405 		if (addrlen != sizeof(u32))
2406 			goto out;
2407 
2408 		addr = *((u32 *)addrp);
2409 
2410 		c = policydb.ocontexts[OCON_NODE];
2411 		while (c) {
2412 			if (c->u.node.addr == (addr & c->u.node.mask))
2413 				break;
2414 			c = c->next;
2415 		}
2416 		break;
2417 	}
2418 
2419 	case AF_INET6:
2420 		rc = -EINVAL;
2421 		if (addrlen != sizeof(u64) * 2)
2422 			goto out;
2423 		c = policydb.ocontexts[OCON_NODE6];
2424 		while (c) {
2425 			if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2426 						c->u.node6.mask))
2427 				break;
2428 			c = c->next;
2429 		}
2430 		break;
2431 
2432 	default:
2433 		rc = 0;
2434 		*out_sid = SECINITSID_NODE;
2435 		goto out;
2436 	}
2437 
2438 	if (c) {
2439 		if (!c->sid[0]) {
2440 			rc = sidtab_context_to_sid(&sidtab,
2441 						   &c->context[0],
2442 						   &c->sid[0]);
2443 			if (rc)
2444 				goto out;
2445 		}
2446 		*out_sid = c->sid[0];
2447 	} else {
2448 		*out_sid = SECINITSID_NODE;
2449 	}
2450 
2451 	rc = 0;
2452 out:
2453 	read_unlock(&policy_rwlock);
2454 	return rc;
2455 }
2456 
2457 #define SIDS_NEL 25
2458 
2459 /**
2460  * security_get_user_sids - Obtain reachable SIDs for a user.
2461  * @fromsid: starting SID
2462  * @username: username
2463  * @sids: array of reachable SIDs for user
2464  * @nel: number of elements in @sids
2465  *
2466  * Generate the set of SIDs for legal security contexts
2467  * for a given user that can be reached by @fromsid.
2468  * Set *@sids to point to a dynamically allocated
2469  * array containing the set of SIDs.  Set *@nel to the
2470  * number of elements in the array.
2471  */
2472 
2473 int security_get_user_sids(u32 fromsid,
2474 			   char *username,
2475 			   u32 **sids,
2476 			   u32 *nel)
2477 {
2478 	struct context *fromcon, usercon;
2479 	u32 *mysids = NULL, *mysids2, sid;
2480 	u32 mynel = 0, maxnel = SIDS_NEL;
2481 	struct user_datum *user;
2482 	struct role_datum *role;
2483 	struct ebitmap_node *rnode, *tnode;
2484 	int rc = 0, i, j;
2485 
2486 	*sids = NULL;
2487 	*nel = 0;
2488 
2489 	if (!ss_initialized)
2490 		goto out;
2491 
2492 	read_lock(&policy_rwlock);
2493 
2494 	context_init(&usercon);
2495 
2496 	rc = -EINVAL;
2497 	fromcon = sidtab_search(&sidtab, fromsid);
2498 	if (!fromcon)
2499 		goto out_unlock;
2500 
2501 	rc = -EINVAL;
2502 	user = hashtab_search(policydb.p_users.table, username);
2503 	if (!user)
2504 		goto out_unlock;
2505 
2506 	usercon.user = user->value;
2507 
2508 	rc = -ENOMEM;
2509 	mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2510 	if (!mysids)
2511 		goto out_unlock;
2512 
2513 	ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2514 		role = policydb.role_val_to_struct[i];
2515 		usercon.role = i + 1;
2516 		ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2517 			usercon.type = j + 1;
2518 
2519 			if (mls_setup_user_range(fromcon, user, &usercon))
2520 				continue;
2521 
2522 			rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2523 			if (rc)
2524 				goto out_unlock;
2525 			if (mynel < maxnel) {
2526 				mysids[mynel++] = sid;
2527 			} else {
2528 				rc = -ENOMEM;
2529 				maxnel += SIDS_NEL;
2530 				mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2531 				if (!mysids2)
2532 					goto out_unlock;
2533 				memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2534 				kfree(mysids);
2535 				mysids = mysids2;
2536 				mysids[mynel++] = sid;
2537 			}
2538 		}
2539 	}
2540 	rc = 0;
2541 out_unlock:
2542 	read_unlock(&policy_rwlock);
2543 	if (rc || !mynel) {
2544 		kfree(mysids);
2545 		goto out;
2546 	}
2547 
2548 	rc = -ENOMEM;
2549 	mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2550 	if (!mysids2) {
2551 		kfree(mysids);
2552 		goto out;
2553 	}
2554 	for (i = 0, j = 0; i < mynel; i++) {
2555 		struct av_decision dummy_avd;
2556 		rc = avc_has_perm_noaudit(fromsid, mysids[i],
2557 					  SECCLASS_PROCESS, /* kernel value */
2558 					  PROCESS__TRANSITION, AVC_STRICT,
2559 					  &dummy_avd);
2560 		if (!rc)
2561 			mysids2[j++] = mysids[i];
2562 		cond_resched();
2563 	}
2564 	rc = 0;
2565 	kfree(mysids);
2566 	*sids = mysids2;
2567 	*nel = j;
2568 out:
2569 	return rc;
2570 }
2571 
2572 /**
2573  * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2574  * @fstype: filesystem type
2575  * @path: path from root of mount
2576  * @sclass: file security class
2577  * @sid: SID for path
2578  *
2579  * Obtain a SID to use for a file in a filesystem that
2580  * cannot support xattr or use a fixed labeling behavior like
2581  * transition SIDs or task SIDs.
2582  *
2583  * The caller must acquire the policy_rwlock before calling this function.
2584  */
2585 static inline int __security_genfs_sid(const char *fstype,
2586 				       char *path,
2587 				       u16 orig_sclass,
2588 				       u32 *sid)
2589 {
2590 	int len;
2591 	u16 sclass;
2592 	struct genfs *genfs;
2593 	struct ocontext *c;
2594 	int rc, cmp = 0;
2595 
2596 	while (path[0] == '/' && path[1] == '/')
2597 		path++;
2598 
2599 	sclass = unmap_class(orig_sclass);
2600 	*sid = SECINITSID_UNLABELED;
2601 
2602 	for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2603 		cmp = strcmp(fstype, genfs->fstype);
2604 		if (cmp <= 0)
2605 			break;
2606 	}
2607 
2608 	rc = -ENOENT;
2609 	if (!genfs || cmp)
2610 		goto out;
2611 
2612 	for (c = genfs->head; c; c = c->next) {
2613 		len = strlen(c->u.name);
2614 		if ((!c->v.sclass || sclass == c->v.sclass) &&
2615 		    (strncmp(c->u.name, path, len) == 0))
2616 			break;
2617 	}
2618 
2619 	rc = -ENOENT;
2620 	if (!c)
2621 		goto out;
2622 
2623 	if (!c->sid[0]) {
2624 		rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]);
2625 		if (rc)
2626 			goto out;
2627 	}
2628 
2629 	*sid = c->sid[0];
2630 	rc = 0;
2631 out:
2632 	return rc;
2633 }
2634 
2635 /**
2636  * security_genfs_sid - Obtain a SID for a file in a filesystem
2637  * @fstype: filesystem type
2638  * @path: path from root of mount
2639  * @sclass: file security class
2640  * @sid: SID for path
2641  *
2642  * Acquire policy_rwlock before calling __security_genfs_sid() and release
2643  * it afterward.
2644  */
2645 int security_genfs_sid(const char *fstype,
2646 		       char *path,
2647 		       u16 orig_sclass,
2648 		       u32 *sid)
2649 {
2650 	int retval;
2651 
2652 	read_lock(&policy_rwlock);
2653 	retval = __security_genfs_sid(fstype, path, orig_sclass, sid);
2654 	read_unlock(&policy_rwlock);
2655 	return retval;
2656 }
2657 
2658 /**
2659  * security_fs_use - Determine how to handle labeling for a filesystem.
2660  * @sb: superblock in question
2661  */
2662 int security_fs_use(struct super_block *sb)
2663 {
2664 	int rc = 0;
2665 	struct ocontext *c;
2666 	struct superblock_security_struct *sbsec = sb->s_security;
2667 	const char *fstype = sb->s_type->name;
2668 
2669 	read_lock(&policy_rwlock);
2670 
2671 	c = policydb.ocontexts[OCON_FSUSE];
2672 	while (c) {
2673 		if (strcmp(fstype, c->u.name) == 0)
2674 			break;
2675 		c = c->next;
2676 	}
2677 
2678 	if (c) {
2679 		sbsec->behavior = c->v.behavior;
2680 		if (!c->sid[0]) {
2681 			rc = sidtab_context_to_sid(&sidtab, &c->context[0],
2682 						   &c->sid[0]);
2683 			if (rc)
2684 				goto out;
2685 		}
2686 		sbsec->sid = c->sid[0];
2687 	} else {
2688 		rc = __security_genfs_sid(fstype, "/", SECCLASS_DIR,
2689 					  &sbsec->sid);
2690 		if (rc) {
2691 			sbsec->behavior = SECURITY_FS_USE_NONE;
2692 			rc = 0;
2693 		} else {
2694 			sbsec->behavior = SECURITY_FS_USE_GENFS;
2695 		}
2696 	}
2697 
2698 out:
2699 	read_unlock(&policy_rwlock);
2700 	return rc;
2701 }
2702 
2703 int security_get_bools(int *len, char ***names, int **values)
2704 {
2705 	int i, rc;
2706 
2707 	read_lock(&policy_rwlock);
2708 	*names = NULL;
2709 	*values = NULL;
2710 
2711 	rc = 0;
2712 	*len = policydb.p_bools.nprim;
2713 	if (!*len)
2714 		goto out;
2715 
2716 	rc = -ENOMEM;
2717 	*names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2718 	if (!*names)
2719 		goto err;
2720 
2721 	rc = -ENOMEM;
2722 	*values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2723 	if (!*values)
2724 		goto err;
2725 
2726 	for (i = 0; i < *len; i++) {
2727 		(*values)[i] = policydb.bool_val_to_struct[i]->state;
2728 
2729 		rc = -ENOMEM;
2730 		(*names)[i] = kstrdup(sym_name(&policydb, SYM_BOOLS, i), GFP_ATOMIC);
2731 		if (!(*names)[i])
2732 			goto err;
2733 	}
2734 	rc = 0;
2735 out:
2736 	read_unlock(&policy_rwlock);
2737 	return rc;
2738 err:
2739 	if (*names) {
2740 		for (i = 0; i < *len; i++)
2741 			kfree((*names)[i]);
2742 	}
2743 	kfree(*values);
2744 	goto out;
2745 }
2746 
2747 
2748 int security_set_bools(int len, int *values)
2749 {
2750 	int i, rc;
2751 	int lenp, seqno = 0;
2752 	struct cond_node *cur;
2753 
2754 	write_lock_irq(&policy_rwlock);
2755 
2756 	rc = -EFAULT;
2757 	lenp = policydb.p_bools.nprim;
2758 	if (len != lenp)
2759 		goto out;
2760 
2761 	for (i = 0; i < len; i++) {
2762 		if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2763 			audit_log(current->audit_context, GFP_ATOMIC,
2764 				AUDIT_MAC_CONFIG_CHANGE,
2765 				"bool=%s val=%d old_val=%d auid=%u ses=%u",
2766 				sym_name(&policydb, SYM_BOOLS, i),
2767 				!!values[i],
2768 				policydb.bool_val_to_struct[i]->state,
2769 				from_kuid(&init_user_ns, audit_get_loginuid(current)),
2770 				audit_get_sessionid(current));
2771 		}
2772 		if (values[i])
2773 			policydb.bool_val_to_struct[i]->state = 1;
2774 		else
2775 			policydb.bool_val_to_struct[i]->state = 0;
2776 	}
2777 
2778 	for (cur = policydb.cond_list; cur; cur = cur->next) {
2779 		rc = evaluate_cond_node(&policydb, cur);
2780 		if (rc)
2781 			goto out;
2782 	}
2783 
2784 	seqno = ++latest_granting;
2785 	rc = 0;
2786 out:
2787 	write_unlock_irq(&policy_rwlock);
2788 	if (!rc) {
2789 		avc_ss_reset(seqno);
2790 		selnl_notify_policyload(seqno);
2791 		selinux_status_update_policyload(seqno);
2792 		selinux_xfrm_notify_policyload();
2793 	}
2794 	return rc;
2795 }
2796 
2797 int security_get_bool_value(int index)
2798 {
2799 	int rc;
2800 	int len;
2801 
2802 	read_lock(&policy_rwlock);
2803 
2804 	rc = -EFAULT;
2805 	len = policydb.p_bools.nprim;
2806 	if (index >= len)
2807 		goto out;
2808 
2809 	rc = policydb.bool_val_to_struct[index]->state;
2810 out:
2811 	read_unlock(&policy_rwlock);
2812 	return rc;
2813 }
2814 
2815 static int security_preserve_bools(struct policydb *p)
2816 {
2817 	int rc, nbools = 0, *bvalues = NULL, i;
2818 	char **bnames = NULL;
2819 	struct cond_bool_datum *booldatum;
2820 	struct cond_node *cur;
2821 
2822 	rc = security_get_bools(&nbools, &bnames, &bvalues);
2823 	if (rc)
2824 		goto out;
2825 	for (i = 0; i < nbools; i++) {
2826 		booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2827 		if (booldatum)
2828 			booldatum->state = bvalues[i];
2829 	}
2830 	for (cur = p->cond_list; cur; cur = cur->next) {
2831 		rc = evaluate_cond_node(p, cur);
2832 		if (rc)
2833 			goto out;
2834 	}
2835 
2836 out:
2837 	if (bnames) {
2838 		for (i = 0; i < nbools; i++)
2839 			kfree(bnames[i]);
2840 	}
2841 	kfree(bnames);
2842 	kfree(bvalues);
2843 	return rc;
2844 }
2845 
2846 /*
2847  * security_sid_mls_copy() - computes a new sid based on the given
2848  * sid and the mls portion of mls_sid.
2849  */
2850 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2851 {
2852 	struct context *context1;
2853 	struct context *context2;
2854 	struct context newcon;
2855 	char *s;
2856 	u32 len;
2857 	int rc;
2858 
2859 	rc = 0;
2860 	if (!ss_initialized || !policydb.mls_enabled) {
2861 		*new_sid = sid;
2862 		goto out;
2863 	}
2864 
2865 	context_init(&newcon);
2866 
2867 	read_lock(&policy_rwlock);
2868 
2869 	rc = -EINVAL;
2870 	context1 = sidtab_search(&sidtab, sid);
2871 	if (!context1) {
2872 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2873 			__func__, sid);
2874 		goto out_unlock;
2875 	}
2876 
2877 	rc = -EINVAL;
2878 	context2 = sidtab_search(&sidtab, mls_sid);
2879 	if (!context2) {
2880 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2881 			__func__, mls_sid);
2882 		goto out_unlock;
2883 	}
2884 
2885 	newcon.user = context1->user;
2886 	newcon.role = context1->role;
2887 	newcon.type = context1->type;
2888 	rc = mls_context_cpy(&newcon, context2);
2889 	if (rc)
2890 		goto out_unlock;
2891 
2892 	/* Check the validity of the new context. */
2893 	if (!policydb_context_isvalid(&policydb, &newcon)) {
2894 		rc = convert_context_handle_invalid_context(&newcon);
2895 		if (rc) {
2896 			if (!context_struct_to_string(&newcon, &s, &len)) {
2897 				audit_log(current->audit_context,
2898 					  GFP_ATOMIC, AUDIT_SELINUX_ERR,
2899 					  "op=security_sid_mls_copy "
2900 					  "invalid_context=%s", s);
2901 				kfree(s);
2902 			}
2903 			goto out_unlock;
2904 		}
2905 	}
2906 
2907 	rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2908 out_unlock:
2909 	read_unlock(&policy_rwlock);
2910 	context_destroy(&newcon);
2911 out:
2912 	return rc;
2913 }
2914 
2915 /**
2916  * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2917  * @nlbl_sid: NetLabel SID
2918  * @nlbl_type: NetLabel labeling protocol type
2919  * @xfrm_sid: XFRM SID
2920  *
2921  * Description:
2922  * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2923  * resolved into a single SID it is returned via @peer_sid and the function
2924  * returns zero.  Otherwise @peer_sid is set to SECSID_NULL and the function
2925  * returns a negative value.  A table summarizing the behavior is below:
2926  *
2927  *                                 | function return |      @sid
2928  *   ------------------------------+-----------------+-----------------
2929  *   no peer labels                |        0        |    SECSID_NULL
2930  *   single peer label             |        0        |    <peer_label>
2931  *   multiple, consistent labels   |        0        |    <peer_label>
2932  *   multiple, inconsistent labels |    -<errno>     |    SECSID_NULL
2933  *
2934  */
2935 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2936 				 u32 xfrm_sid,
2937 				 u32 *peer_sid)
2938 {
2939 	int rc;
2940 	struct context *nlbl_ctx;
2941 	struct context *xfrm_ctx;
2942 
2943 	*peer_sid = SECSID_NULL;
2944 
2945 	/* handle the common (which also happens to be the set of easy) cases
2946 	 * right away, these two if statements catch everything involving a
2947 	 * single or absent peer SID/label */
2948 	if (xfrm_sid == SECSID_NULL) {
2949 		*peer_sid = nlbl_sid;
2950 		return 0;
2951 	}
2952 	/* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2953 	 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2954 	 * is present */
2955 	if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2956 		*peer_sid = xfrm_sid;
2957 		return 0;
2958 	}
2959 
2960 	/* we don't need to check ss_initialized here since the only way both
2961 	 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2962 	 * security server was initialized and ss_initialized was true */
2963 	if (!policydb.mls_enabled)
2964 		return 0;
2965 
2966 	read_lock(&policy_rwlock);
2967 
2968 	rc = -EINVAL;
2969 	nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2970 	if (!nlbl_ctx) {
2971 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2972 		       __func__, nlbl_sid);
2973 		goto out;
2974 	}
2975 	rc = -EINVAL;
2976 	xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2977 	if (!xfrm_ctx) {
2978 		printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2979 		       __func__, xfrm_sid);
2980 		goto out;
2981 	}
2982 	rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2983 	if (rc)
2984 		goto out;
2985 
2986 	/* at present NetLabel SIDs/labels really only carry MLS
2987 	 * information so if the MLS portion of the NetLabel SID
2988 	 * matches the MLS portion of the labeled XFRM SID/label
2989 	 * then pass along the XFRM SID as it is the most
2990 	 * expressive */
2991 	*peer_sid = xfrm_sid;
2992 out:
2993 	read_unlock(&policy_rwlock);
2994 	return rc;
2995 }
2996 
2997 static int get_classes_callback(void *k, void *d, void *args)
2998 {
2999 	struct class_datum *datum = d;
3000 	char *name = k, **classes = args;
3001 	int value = datum->value - 1;
3002 
3003 	classes[value] = kstrdup(name, GFP_ATOMIC);
3004 	if (!classes[value])
3005 		return -ENOMEM;
3006 
3007 	return 0;
3008 }
3009 
3010 int security_get_classes(char ***classes, int *nclasses)
3011 {
3012 	int rc;
3013 
3014 	read_lock(&policy_rwlock);
3015 
3016 	rc = -ENOMEM;
3017 	*nclasses = policydb.p_classes.nprim;
3018 	*classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3019 	if (!*classes)
3020 		goto out;
3021 
3022 	rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
3023 			*classes);
3024 	if (rc) {
3025 		int i;
3026 		for (i = 0; i < *nclasses; i++)
3027 			kfree((*classes)[i]);
3028 		kfree(*classes);
3029 	}
3030 
3031 out:
3032 	read_unlock(&policy_rwlock);
3033 	return rc;
3034 }
3035 
3036 static int get_permissions_callback(void *k, void *d, void *args)
3037 {
3038 	struct perm_datum *datum = d;
3039 	char *name = k, **perms = args;
3040 	int value = datum->value - 1;
3041 
3042 	perms[value] = kstrdup(name, GFP_ATOMIC);
3043 	if (!perms[value])
3044 		return -ENOMEM;
3045 
3046 	return 0;
3047 }
3048 
3049 int security_get_permissions(char *class, char ***perms, int *nperms)
3050 {
3051 	int rc, i;
3052 	struct class_datum *match;
3053 
3054 	read_lock(&policy_rwlock);
3055 
3056 	rc = -EINVAL;
3057 	match = hashtab_search(policydb.p_classes.table, class);
3058 	if (!match) {
3059 		printk(KERN_ERR "SELinux: %s:  unrecognized class %s\n",
3060 			__func__, class);
3061 		goto out;
3062 	}
3063 
3064 	rc = -ENOMEM;
3065 	*nperms = match->permissions.nprim;
3066 	*perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3067 	if (!*perms)
3068 		goto out;
3069 
3070 	if (match->comdatum) {
3071 		rc = hashtab_map(match->comdatum->permissions.table,
3072 				get_permissions_callback, *perms);
3073 		if (rc)
3074 			goto err;
3075 	}
3076 
3077 	rc = hashtab_map(match->permissions.table, get_permissions_callback,
3078 			*perms);
3079 	if (rc)
3080 		goto err;
3081 
3082 out:
3083 	read_unlock(&policy_rwlock);
3084 	return rc;
3085 
3086 err:
3087 	read_unlock(&policy_rwlock);
3088 	for (i = 0; i < *nperms; i++)
3089 		kfree((*perms)[i]);
3090 	kfree(*perms);
3091 	return rc;
3092 }
3093 
3094 int security_get_reject_unknown(void)
3095 {
3096 	return policydb.reject_unknown;
3097 }
3098 
3099 int security_get_allow_unknown(void)
3100 {
3101 	return policydb.allow_unknown;
3102 }
3103 
3104 /**
3105  * security_policycap_supported - Check for a specific policy capability
3106  * @req_cap: capability
3107  *
3108  * Description:
3109  * This function queries the currently loaded policy to see if it supports the
3110  * capability specified by @req_cap.  Returns true (1) if the capability is
3111  * supported, false (0) if it isn't supported.
3112  *
3113  */
3114 int security_policycap_supported(unsigned int req_cap)
3115 {
3116 	int rc;
3117 
3118 	read_lock(&policy_rwlock);
3119 	rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
3120 	read_unlock(&policy_rwlock);
3121 
3122 	return rc;
3123 }
3124 
3125 struct selinux_audit_rule {
3126 	u32 au_seqno;
3127 	struct context au_ctxt;
3128 };
3129 
3130 void selinux_audit_rule_free(void *vrule)
3131 {
3132 	struct selinux_audit_rule *rule = vrule;
3133 
3134 	if (rule) {
3135 		context_destroy(&rule->au_ctxt);
3136 		kfree(rule);
3137 	}
3138 }
3139 
3140 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3141 {
3142 	struct selinux_audit_rule *tmprule;
3143 	struct role_datum *roledatum;
3144 	struct type_datum *typedatum;
3145 	struct user_datum *userdatum;
3146 	struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3147 	int rc = 0;
3148 
3149 	*rule = NULL;
3150 
3151 	if (!ss_initialized)
3152 		return -EOPNOTSUPP;
3153 
3154 	switch (field) {
3155 	case AUDIT_SUBJ_USER:
3156 	case AUDIT_SUBJ_ROLE:
3157 	case AUDIT_SUBJ_TYPE:
3158 	case AUDIT_OBJ_USER:
3159 	case AUDIT_OBJ_ROLE:
3160 	case AUDIT_OBJ_TYPE:
3161 		/* only 'equals' and 'not equals' fit user, role, and type */
3162 		if (op != Audit_equal && op != Audit_not_equal)
3163 			return -EINVAL;
3164 		break;
3165 	case AUDIT_SUBJ_SEN:
3166 	case AUDIT_SUBJ_CLR:
3167 	case AUDIT_OBJ_LEV_LOW:
3168 	case AUDIT_OBJ_LEV_HIGH:
3169 		/* we do not allow a range, indicated by the presence of '-' */
3170 		if (strchr(rulestr, '-'))
3171 			return -EINVAL;
3172 		break;
3173 	default:
3174 		/* only the above fields are valid */
3175 		return -EINVAL;
3176 	}
3177 
3178 	tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3179 	if (!tmprule)
3180 		return -ENOMEM;
3181 
3182 	context_init(&tmprule->au_ctxt);
3183 
3184 	read_lock(&policy_rwlock);
3185 
3186 	tmprule->au_seqno = latest_granting;
3187 
3188 	switch (field) {
3189 	case AUDIT_SUBJ_USER:
3190 	case AUDIT_OBJ_USER:
3191 		rc = -EINVAL;
3192 		userdatum = hashtab_search(policydb.p_users.table, rulestr);
3193 		if (!userdatum)
3194 			goto out;
3195 		tmprule->au_ctxt.user = userdatum->value;
3196 		break;
3197 	case AUDIT_SUBJ_ROLE:
3198 	case AUDIT_OBJ_ROLE:
3199 		rc = -EINVAL;
3200 		roledatum = hashtab_search(policydb.p_roles.table, rulestr);
3201 		if (!roledatum)
3202 			goto out;
3203 		tmprule->au_ctxt.role = roledatum->value;
3204 		break;
3205 	case AUDIT_SUBJ_TYPE:
3206 	case AUDIT_OBJ_TYPE:
3207 		rc = -EINVAL;
3208 		typedatum = hashtab_search(policydb.p_types.table, rulestr);
3209 		if (!typedatum)
3210 			goto out;
3211 		tmprule->au_ctxt.type = typedatum->value;
3212 		break;
3213 	case AUDIT_SUBJ_SEN:
3214 	case AUDIT_SUBJ_CLR:
3215 	case AUDIT_OBJ_LEV_LOW:
3216 	case AUDIT_OBJ_LEV_HIGH:
3217 		rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
3218 		if (rc)
3219 			goto out;
3220 		break;
3221 	}
3222 	rc = 0;
3223 out:
3224 	read_unlock(&policy_rwlock);
3225 
3226 	if (rc) {
3227 		selinux_audit_rule_free(tmprule);
3228 		tmprule = NULL;
3229 	}
3230 
3231 	*rule = tmprule;
3232 
3233 	return rc;
3234 }
3235 
3236 /* Check to see if the rule contains any selinux fields */
3237 int selinux_audit_rule_known(struct audit_krule *rule)
3238 {
3239 	int i;
3240 
3241 	for (i = 0; i < rule->field_count; i++) {
3242 		struct audit_field *f = &rule->fields[i];
3243 		switch (f->type) {
3244 		case AUDIT_SUBJ_USER:
3245 		case AUDIT_SUBJ_ROLE:
3246 		case AUDIT_SUBJ_TYPE:
3247 		case AUDIT_SUBJ_SEN:
3248 		case AUDIT_SUBJ_CLR:
3249 		case AUDIT_OBJ_USER:
3250 		case AUDIT_OBJ_ROLE:
3251 		case AUDIT_OBJ_TYPE:
3252 		case AUDIT_OBJ_LEV_LOW:
3253 		case AUDIT_OBJ_LEV_HIGH:
3254 			return 1;
3255 		}
3256 	}
3257 
3258 	return 0;
3259 }
3260 
3261 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
3262 			     struct audit_context *actx)
3263 {
3264 	struct context *ctxt;
3265 	struct mls_level *level;
3266 	struct selinux_audit_rule *rule = vrule;
3267 	int match = 0;
3268 
3269 	if (unlikely(!rule)) {
3270 		WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3271 		return -ENOENT;
3272 	}
3273 
3274 	read_lock(&policy_rwlock);
3275 
3276 	if (rule->au_seqno < latest_granting) {
3277 		match = -ESTALE;
3278 		goto out;
3279 	}
3280 
3281 	ctxt = sidtab_search(&sidtab, sid);
3282 	if (unlikely(!ctxt)) {
3283 		WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3284 			  sid);
3285 		match = -ENOENT;
3286 		goto out;
3287 	}
3288 
3289 	/* a field/op pair that is not caught here will simply fall through
3290 	   without a match */
3291 	switch (field) {
3292 	case AUDIT_SUBJ_USER:
3293 	case AUDIT_OBJ_USER:
3294 		switch (op) {
3295 		case Audit_equal:
3296 			match = (ctxt->user == rule->au_ctxt.user);
3297 			break;
3298 		case Audit_not_equal:
3299 			match = (ctxt->user != rule->au_ctxt.user);
3300 			break;
3301 		}
3302 		break;
3303 	case AUDIT_SUBJ_ROLE:
3304 	case AUDIT_OBJ_ROLE:
3305 		switch (op) {
3306 		case Audit_equal:
3307 			match = (ctxt->role == rule->au_ctxt.role);
3308 			break;
3309 		case Audit_not_equal:
3310 			match = (ctxt->role != rule->au_ctxt.role);
3311 			break;
3312 		}
3313 		break;
3314 	case AUDIT_SUBJ_TYPE:
3315 	case AUDIT_OBJ_TYPE:
3316 		switch (op) {
3317 		case Audit_equal:
3318 			match = (ctxt->type == rule->au_ctxt.type);
3319 			break;
3320 		case Audit_not_equal:
3321 			match = (ctxt->type != rule->au_ctxt.type);
3322 			break;
3323 		}
3324 		break;
3325 	case AUDIT_SUBJ_SEN:
3326 	case AUDIT_SUBJ_CLR:
3327 	case AUDIT_OBJ_LEV_LOW:
3328 	case AUDIT_OBJ_LEV_HIGH:
3329 		level = ((field == AUDIT_SUBJ_SEN ||
3330 			  field == AUDIT_OBJ_LEV_LOW) ?
3331 			 &ctxt->range.level[0] : &ctxt->range.level[1]);
3332 		switch (op) {
3333 		case Audit_equal:
3334 			match = mls_level_eq(&rule->au_ctxt.range.level[0],
3335 					     level);
3336 			break;
3337 		case Audit_not_equal:
3338 			match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3339 					      level);
3340 			break;
3341 		case Audit_lt:
3342 			match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3343 					       level) &&
3344 				 !mls_level_eq(&rule->au_ctxt.range.level[0],
3345 					       level));
3346 			break;
3347 		case Audit_le:
3348 			match = mls_level_dom(&rule->au_ctxt.range.level[0],
3349 					      level);
3350 			break;
3351 		case Audit_gt:
3352 			match = (mls_level_dom(level,
3353 					      &rule->au_ctxt.range.level[0]) &&
3354 				 !mls_level_eq(level,
3355 					       &rule->au_ctxt.range.level[0]));
3356 			break;
3357 		case Audit_ge:
3358 			match = mls_level_dom(level,
3359 					      &rule->au_ctxt.range.level[0]);
3360 			break;
3361 		}
3362 	}
3363 
3364 out:
3365 	read_unlock(&policy_rwlock);
3366 	return match;
3367 }
3368 
3369 static int (*aurule_callback)(void) = audit_update_lsm_rules;
3370 
3371 static int aurule_avc_callback(u32 event)
3372 {
3373 	int err = 0;
3374 
3375 	if (event == AVC_CALLBACK_RESET && aurule_callback)
3376 		err = aurule_callback();
3377 	return err;
3378 }
3379 
3380 static int __init aurule_init(void)
3381 {
3382 	int err;
3383 
3384 	err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3385 	if (err)
3386 		panic("avc_add_callback() failed, error %d\n", err);
3387 
3388 	return err;
3389 }
3390 __initcall(aurule_init);
3391 
3392 #ifdef CONFIG_NETLABEL
3393 /**
3394  * security_netlbl_cache_add - Add an entry to the NetLabel cache
3395  * @secattr: the NetLabel packet security attributes
3396  * @sid: the SELinux SID
3397  *
3398  * Description:
3399  * Attempt to cache the context in @ctx, which was derived from the packet in
3400  * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
3401  * already been initialized.
3402  *
3403  */
3404 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3405 				      u32 sid)
3406 {
3407 	u32 *sid_cache;
3408 
3409 	sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3410 	if (sid_cache == NULL)
3411 		return;
3412 	secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3413 	if (secattr->cache == NULL) {
3414 		kfree(sid_cache);
3415 		return;
3416 	}
3417 
3418 	*sid_cache = sid;
3419 	secattr->cache->free = kfree;
3420 	secattr->cache->data = sid_cache;
3421 	secattr->flags |= NETLBL_SECATTR_CACHE;
3422 }
3423 
3424 /**
3425  * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3426  * @secattr: the NetLabel packet security attributes
3427  * @sid: the SELinux SID
3428  *
3429  * Description:
3430  * Convert the given NetLabel security attributes in @secattr into a
3431  * SELinux SID.  If the @secattr field does not contain a full SELinux
3432  * SID/context then use SECINITSID_NETMSG as the foundation.  If possible the
3433  * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3434  * allow the @secattr to be used by NetLabel to cache the secattr to SID
3435  * conversion for future lookups.  Returns zero on success, negative values on
3436  * failure.
3437  *
3438  */
3439 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3440 				   u32 *sid)
3441 {
3442 	int rc;
3443 	struct context *ctx;
3444 	struct context ctx_new;
3445 
3446 	if (!ss_initialized) {
3447 		*sid = SECSID_NULL;
3448 		return 0;
3449 	}
3450 
3451 	read_lock(&policy_rwlock);
3452 
3453 	if (secattr->flags & NETLBL_SECATTR_CACHE)
3454 		*sid = *(u32 *)secattr->cache->data;
3455 	else if (secattr->flags & NETLBL_SECATTR_SECID)
3456 		*sid = secattr->attr.secid;
3457 	else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3458 		rc = -EIDRM;
3459 		ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3460 		if (ctx == NULL)
3461 			goto out;
3462 
3463 		context_init(&ctx_new);
3464 		ctx_new.user = ctx->user;
3465 		ctx_new.role = ctx->role;
3466 		ctx_new.type = ctx->type;
3467 		mls_import_netlbl_lvl(&ctx_new, secattr);
3468 		if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3469 			rc = mls_import_netlbl_cat(&ctx_new, secattr);
3470 			if (rc)
3471 				goto out;
3472 		}
3473 		rc = -EIDRM;
3474 		if (!mls_context_isvalid(&policydb, &ctx_new))
3475 			goto out_free;
3476 
3477 		rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3478 		if (rc)
3479 			goto out_free;
3480 
3481 		security_netlbl_cache_add(secattr, *sid);
3482 
3483 		ebitmap_destroy(&ctx_new.range.level[0].cat);
3484 	} else
3485 		*sid = SECSID_NULL;
3486 
3487 	read_unlock(&policy_rwlock);
3488 	return 0;
3489 out_free:
3490 	ebitmap_destroy(&ctx_new.range.level[0].cat);
3491 out:
3492 	read_unlock(&policy_rwlock);
3493 	return rc;
3494 }
3495 
3496 /**
3497  * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3498  * @sid: the SELinux SID
3499  * @secattr: the NetLabel packet security attributes
3500  *
3501  * Description:
3502  * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3503  * Returns zero on success, negative values on failure.
3504  *
3505  */
3506 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3507 {
3508 	int rc;
3509 	struct context *ctx;
3510 
3511 	if (!ss_initialized)
3512 		return 0;
3513 
3514 	read_lock(&policy_rwlock);
3515 
3516 	rc = -ENOENT;
3517 	ctx = sidtab_search(&sidtab, sid);
3518 	if (ctx == NULL)
3519 		goto out;
3520 
3521 	rc = -ENOMEM;
3522 	secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1),
3523 				  GFP_ATOMIC);
3524 	if (secattr->domain == NULL)
3525 		goto out;
3526 
3527 	secattr->attr.secid = sid;
3528 	secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3529 	mls_export_netlbl_lvl(ctx, secattr);
3530 	rc = mls_export_netlbl_cat(ctx, secattr);
3531 out:
3532 	read_unlock(&policy_rwlock);
3533 	return rc;
3534 }
3535 #endif /* CONFIG_NETLABEL */
3536 
3537 /**
3538  * security_read_policy - read the policy.
3539  * @data: binary policy data
3540  * @len: length of data in bytes
3541  *
3542  */
3543 int security_read_policy(void **data, size_t *len)
3544 {
3545 	int rc;
3546 	struct policy_file fp;
3547 
3548 	if (!ss_initialized)
3549 		return -EINVAL;
3550 
3551 	*len = security_policydb_len();
3552 
3553 	*data = vmalloc_user(*len);
3554 	if (!*data)
3555 		return -ENOMEM;
3556 
3557 	fp.data = *data;
3558 	fp.len = *len;
3559 
3560 	read_lock(&policy_rwlock);
3561 	rc = policydb_write(&policydb, &fp);
3562 	read_unlock(&policy_rwlock);
3563 
3564 	if (rc)
3565 		return rc;
3566 
3567 	*len = (unsigned long)fp.data - (unsigned long)*data;
3568 	return 0;
3569 
3570 }
3571