1	// SPDX-License-Identifier: GPL-2.0-only
2	/*
3	* Implementation of the security services.
4	*
5	* Authors : Stephen Smalley, <stephen.smalley.work@gmail.com>
6	* James Morris <jmorris@redhat.com>
7	*
8	* Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
9	*
10	* Support for enhanced MLS infrastructure.
11	* Support for context based audit filters.
12	*
13	* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
14	*
15	* Added conditional policy language extensions
16	*
17	* Updated: Hewlett-Packard <paul@paul-moore.com>
18	*
19	* Added support for NetLabel
20	* Added support for the policy capability bitmap
21	*
22	* Updated: Chad Sellers <csellers@tresys.com>
23	*
24	* Added validation of kernel classes and permissions
25	*
26	* Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
27	*
28	* Added support for bounds domain and audit messaged on masked permissions
29	*
30	* Updated: Guido Trentalancia <guido@trentalancia.com>
31	*
32	* Added support for runtime switching of the policy type
33	*
34	* Copyright (C) 2008, 2009 NEC Corporation
35	* Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
36	* Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
37	* Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
38	* Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
39	*/
40	#include <linux/kernel.h>
41	#include <linux/slab.h>
42	#include <linux/string.h>
43	#include <linux/spinlock.h>
44	#include <linux/rcupdate.h>
45	#include <linux/errno.h>
46	#include <linux/in.h>
47	#include <linux/sched.h>
48	#include <linux/audit.h>
49	#include <linux/vmalloc.h>
50	#include <linux/lsm_hooks.h>
51	#include <net/netlabel.h>
52
53	#include "flask.h"
54	#include "avc.h"
55	#include "avc_ss.h"
56	#include "security.h"
57	#include "context.h"
58	#include "policydb.h"
59	#include "sidtab.h"
60	#include "services.h"
61	#include "conditional.h"
62	#include "mls.h"
63	#include "objsec.h"
64	#include "netlabel.h"
65	#include "xfrm.h"
66	#include "ebitmap.h"
67	#include "audit.h"
68	#include "policycap_names.h"
69	#include "ima.h"
70
71	struct selinux_policy_convert_data {
72	struct convert_context_args args;
73	struct sidtab_convert_params sidtab_params;
74	};
75
76	/* Forward declaration. */
77	static int context_struct_to_string(struct policydb *policydb,
78	struct context *context,
79	char **scontext,
80	u32 *scontext_len);
81
82	static int sidtab_entry_to_string(struct policydb *policydb,
83	struct sidtab *sidtab,
84	struct sidtab_entry *entry,
85	char **scontext,
86	u32 *scontext_len);
87
88	static void context_struct_compute_av(struct policydb *policydb,
89	struct context *scontext,
90	struct context *tcontext,
91	u16 tclass,
92	struct av_decision *avd,
93	struct extended_perms *xperms);
94
95	static int selinux_set_mapping(struct policydb *pol,
96	const struct security_class_mapping *map,
97	struct selinux_map *out_map)
98	{
99	u16 i, j;
100	bool print_unknown_handle = false;
101
102	/* Find number of classes in the input mapping */
103	if (!map)
104	return -EINVAL;
105	i = 0;
106	while (map[i].name)
107	i++;
108
109	/* Allocate space for the class records, plus one for class zero */
110	out_map->mapping = kcalloc(n: ++i, size: sizeof(*out_map->mapping), GFP_ATOMIC);
111	if (!out_map->mapping)
112	return -ENOMEM;
113
114	/* Store the raw class and permission values */
115	j = 0;
116	while (map[j].name) {
117	const struct security_class_mapping *p_in = map + (j++);
118	struct selinux_mapping *p_out = out_map->mapping + j;
119	u16 k;
120
121	/* An empty class string skips ahead */
122	if (!strcmp(p_in->name, "")) {
123	p_out->num_perms = 0;
124	continue;
125	}
126
127	p_out->value = string_to_security_class(p: pol, name: p_in->name);
128	if (!p_out->value) {
129	pr_info("SELinux: Class %s not defined in policy.\n",
130	p_in->name);
131	if (pol->reject_unknown)
132	goto err;
133	p_out->num_perms = 0;
134	print_unknown_handle = true;
135	continue;
136	}
137
138	k = 0;
139	while (p_in->perms[k]) {
140	/* An empty permission string skips ahead */
141	if (!*p_in->perms[k]) {
142	k++;
143	continue;
144	}
145	p_out->perms[k] = string_to_av_perm(p: pol, tclass: p_out->value,
146	name: p_in->perms[k]);
147	if (!p_out->perms[k]) {
148	pr_info("SELinux: Permission %s in class %s not defined in policy.\n",
149	p_in->perms[k], p_in->name);
150	if (pol->reject_unknown)
151	goto err;
152	print_unknown_handle = true;
153	}
154
155	k++;
156	}
157	p_out->num_perms = k;
158	}
159
160	if (print_unknown_handle)
161	pr_info("SELinux: the above unknown classes and permissions will be %s\n",
162	pol->allow_unknown ? "allowed" : "denied");
163
164	out_map->size = i;
165	return 0;
166	err:
167	kfree(objp: out_map->mapping);
168	out_map->mapping = NULL;
169	return -EINVAL;
170	}
171
172	/*
173	* Get real, policy values from mapped values
174	*/
175
176	static u16 unmap_class(struct selinux_map *map, u16 tclass)
177	{
178	if (tclass < map->size)
179	return map->mapping[tclass].value;
180
181	return tclass;
182	}
183
184	/*
185	* Get kernel value for class from its policy value
186	*/
187	static u16 map_class(struct selinux_map *map, u16 pol_value)
188	{
189	u16 i;
190
191	for (i = 1; i < map->size; i++) {
192	if (map->mapping[i].value == pol_value)
193	return i;
194	}
195
196	return SECCLASS_NULL;
197	}
198
199	static void map_decision(struct selinux_map *map,
200	u16 tclass, struct av_decision *avd,
201	int allow_unknown)
202	{
203	if (tclass < map->size) {
204	struct selinux_mapping *mapping = &map->mapping[tclass];
205	unsigned int i, n = mapping->num_perms;
206	u32 result;
207
208	for (i = 0, result = 0; i < n; i++) {
209	if (avd->allowed & mapping->perms[i])
210	result |= (u32)1<<i;
211	if (allow_unknown && !mapping->perms[i])
212	result |= (u32)1<<i;
213	}
214	avd->allowed = result;
215
216	for (i = 0, result = 0; i < n; i++)
217	if (avd->auditallow & mapping->perms[i])
218	result |= (u32)1<<i;
219	avd->auditallow = result;
220
221	for (i = 0, result = 0; i < n; i++) {
222	if (avd->auditdeny & mapping->perms[i])
223	result |= (u32)1<<i;
224	if (!allow_unknown && !mapping->perms[i])
225	result |= (u32)1<<i;
226	}
227	/*
228	* In case the kernel has a bug and requests a permission
229	* between num_perms and the maximum permission number, we
230	* should audit that denial
231	*/
232	for (; i < (sizeof(u32)*8); i++)
233	result |= (u32)1<<i;
234	avd->auditdeny = result;
235	}
236	}
237
238	int security_mls_enabled(void)
239	{
240	int mls_enabled;
241	struct selinux_policy *policy;
242
243	if (!selinux_initialized())
244	return 0;
245
246	rcu_read_lock();
247	policy = rcu_dereference(selinux_state.policy);
248	mls_enabled = policy->policydb.mls_enabled;
249	rcu_read_unlock();
250	return mls_enabled;
251	}
252
253	/*
254	* Return the boolean value of a constraint expression
255	* when it is applied to the specified source and target
256	* security contexts.
257	*
258	* xcontext is a special beast... It is used by the validatetrans rules
259	* only. For these rules, scontext is the context before the transition,
260	* tcontext is the context after the transition, and xcontext is the context
261	* of the process performing the transition. All other callers of
262	* constraint_expr_eval should pass in NULL for xcontext.
263	*/
264	static int constraint_expr_eval(struct policydb *policydb,
265	struct context *scontext,
266	struct context *tcontext,
267	struct context *xcontext,
268	struct constraint_expr *cexpr)
269	{
270	u32 val1, val2;
271	struct context *c;
272	struct role_datum *r1, *r2;
273	struct mls_level *l1, *l2;
274	struct constraint_expr *e;
275	int s[CEXPR_MAXDEPTH];
276	int sp = -1;
277
278	for (e = cexpr; e; e = e->next) {
279	switch (e->expr_type) {
280	case CEXPR_NOT:
281	BUG_ON(sp < 0);
282	s[sp] = !s[sp];
283	break;
284	case CEXPR_AND:
285	BUG_ON(sp < 1);
286	sp--;
287	s[sp] &= s[sp + 1];
288	break;
289	case CEXPR_OR:
290	BUG_ON(sp < 1);
291	sp--;
292	s[sp] |= s[sp + 1];
293	break;
294	case CEXPR_ATTR:
295	if (sp == (CEXPR_MAXDEPTH - 1))
296	return 0;
297	switch (e->attr) {
298	case CEXPR_USER:
299	val1 = scontext->user;
300	val2 = tcontext->user;
301	break;
302	case CEXPR_TYPE:
303	val1 = scontext->type;
304	val2 = tcontext->type;
305	break;
306	case CEXPR_ROLE:
307	val1 = scontext->role;
308	val2 = tcontext->role;
309	r1 = policydb->role_val_to_struct[val1 - 1];
310	r2 = policydb->role_val_to_struct[val2 - 1];
311	switch (e->op) {
312	case CEXPR_DOM:
313	s[++sp] = ebitmap_get_bit(e: &r1->dominates,
314	bit: val2 - 1);
315	continue;
316	case CEXPR_DOMBY:
317	s[++sp] = ebitmap_get_bit(e: &r2->dominates,
318	bit: val1 - 1);
319	continue;
320	case CEXPR_INCOMP:
321	s[++sp] = (!ebitmap_get_bit(e: &r1->dominates,
322	bit: val2 - 1) &&
323	!ebitmap_get_bit(e: &r2->dominates,
324	bit: val1 - 1));
325	continue;
326	default:
327	break;
328	}
329	break;
330	case CEXPR_L1L2:
331	l1 = &(scontext->range.level[0]);
332	l2 = &(tcontext->range.level[0]);
333	goto mls_ops;
334	case CEXPR_L1H2:
335	l1 = &(scontext->range.level[0]);
336	l2 = &(tcontext->range.level[1]);
337	goto mls_ops;
338	case CEXPR_H1L2:
339	l1 = &(scontext->range.level[1]);
340	l2 = &(tcontext->range.level[0]);
341	goto mls_ops;
342	case CEXPR_H1H2:
343	l1 = &(scontext->range.level[1]);
344	l2 = &(tcontext->range.level[1]);
345	goto mls_ops;
346	case CEXPR_L1H1:
347	l1 = &(scontext->range.level[0]);
348	l2 = &(scontext->range.level[1]);
349	goto mls_ops;
350	case CEXPR_L2H2:
351	l1 = &(tcontext->range.level[0]);
352	l2 = &(tcontext->range.level[1]);
353	goto mls_ops;
354	mls_ops:
355	switch (e->op) {
356	case CEXPR_EQ:
357	s[++sp] = mls_level_eq(l1, l2);
358	continue;
359	case CEXPR_NEQ:
360	s[++sp] = !mls_level_eq(l1, l2);
361	continue;
362	case CEXPR_DOM:
363	s[++sp] = mls_level_dom(l1, l2);
364	continue;
365	case CEXPR_DOMBY:
366	s[++sp] = mls_level_dom(l1: l2, l2: l1);
367	continue;
368	case CEXPR_INCOMP:
369	s[++sp] = mls_level_incomp(l2, l1);
370	continue;
371	default:
372	BUG();
373	return 0;
374	}
375	break;
376	default:
377	BUG();
378	return 0;
379	}
380
381	switch (e->op) {
382	case CEXPR_EQ:
383	s[++sp] = (val1 == val2);
384	break;
385	case CEXPR_NEQ:
386	s[++sp] = (val1 != val2);
387	break;
388	default:
389	BUG();
390	return 0;
391	}
392	break;
393	case CEXPR_NAMES:
394	if (sp == (CEXPR_MAXDEPTH-1))
395	return 0;
396	c = scontext;
397	if (e->attr & CEXPR_TARGET)
398	c = tcontext;
399	else if (e->attr & CEXPR_XTARGET) {
400	c = xcontext;
401	if (!c) {
402	BUG();
403	return 0;
404	}
405	}
406	if (e->attr & CEXPR_USER)
407	val1 = c->user;
408	else if (e->attr & CEXPR_ROLE)
409	val1 = c->role;
410	else if (e->attr & CEXPR_TYPE)
411	val1 = c->type;
412	else {
413	BUG();
414	return 0;
415	}
416
417	switch (e->op) {
418	case CEXPR_EQ:
419	s[++sp] = ebitmap_get_bit(e: &e->names, bit: val1 - 1);
420	break;
421	case CEXPR_NEQ:
422	s[++sp] = !ebitmap_get_bit(e: &e->names, bit: val1 - 1);
423	break;
424	default:
425	BUG();
426	return 0;
427	}
428	break;
429	default:
430	BUG();
431	return 0;
432	}
433	}
434
435	BUG_ON(sp != 0);
436	return s[0];
437	}
438
439	/*
440	* security_dump_masked_av - dumps masked permissions during
441	* security_compute_av due to RBAC, MLS/Constraint and Type bounds.
442	*/
443	static int dump_masked_av_helper(void *k, void *d, void *args)
444	{
445	struct perm_datum *pdatum = d;
446	char **permission_names = args;
447
448	BUG_ON(pdatum->value < 1 || pdatum->value > 32);
449
450	permission_names[pdatum->value - 1] = (char *)k;
451
452	return 0;
453	}
454
455	static void security_dump_masked_av(struct policydb *policydb,
456	struct context *scontext,
457	struct context *tcontext,
458	u16 tclass,
459	u32 permissions,
460	const char *reason)
461	{
462	struct common_datum *common_dat;
463	struct class_datum *tclass_dat;
464	struct audit_buffer *ab;
465	char *tclass_name;
466	char *scontext_name = NULL;
467	char *tcontext_name = NULL;
468	char *permission_names[32];
469	int index;
470	u32 length;
471	bool need_comma = false;
472
473	if (!permissions)
474	return;
475
476	tclass_name = sym_name(p: policydb, SYM_CLASSES, element_nr: tclass - 1);
477	tclass_dat = policydb->class_val_to_struct[tclass - 1];
478	common_dat = tclass_dat->comdatum;
479
480	/* init permission_names */
481	if (common_dat &&
482	hashtab_map(h: &common_dat->permissions.table,
483	apply: dump_masked_av_helper, args: permission_names) < 0)
484	goto out;
485
486	if (hashtab_map(h: &tclass_dat->permissions.table,
487	apply: dump_masked_av_helper, args: permission_names) < 0)
488	goto out;
489
490	/* get scontext/tcontext in text form */
491	if (context_struct_to_string(policydb, context: scontext,
492	scontext: &scontext_name, scontext_len: &length) < 0)
493	goto out;
494
495	if (context_struct_to_string(policydb, context: tcontext,
496	scontext: &tcontext_name, scontext_len: &length) < 0)
497	goto out;
498
499	/* audit a message */
500	ab = audit_log_start(ctx: audit_context(),
501	GFP_ATOMIC, AUDIT_SELINUX_ERR);
502	if (!ab)
503	goto out;
504
505	audit_log_format(ab, fmt: "op=security_compute_av reason=%s "
506	"scontext=%s tcontext=%s tclass=%s perms=",
507	reason, scontext_name, tcontext_name, tclass_name);
508
509	for (index = 0; index < 32; index++) {
510	u32 mask = (1 << index);
511
512	if ((mask & permissions) == 0)
513	continue;
514
515	audit_log_format(ab, fmt: "%s%s",
516	need_comma ? "," : "",
517	permission_names[index]
518	? permission_names[index] : "????");
519	need_comma = true;
520	}
521	audit_log_end(ab);
522	out:
523	/* release scontext/tcontext */
524	kfree(objp: tcontext_name);
525	kfree(objp: scontext_name);
526	}
527
528	/*
529	* security_boundary_permission - drops violated permissions
530	* on boundary constraint.
531	*/
532	static void type_attribute_bounds_av(struct policydb *policydb,
533	struct context *scontext,
534	struct context *tcontext,
535	u16 tclass,
536	struct av_decision *avd)
537	{
538	struct context lo_scontext;
539	struct context lo_tcontext, *tcontextp = tcontext;
540	struct av_decision lo_avd;
541	struct type_datum *source;
542	struct type_datum *target;
543	u32 masked = 0;
544
545	source = policydb->type_val_to_struct[scontext->type - 1];
546	BUG_ON(!source);
547
548	if (!source->bounds)
549	return;
550
551	target = policydb->type_val_to_struct[tcontext->type - 1];
552	BUG_ON(!target);
553
554	memset(&lo_avd, 0, sizeof(lo_avd));
555
556	memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
557	lo_scontext.type = source->bounds;
558
559	if (target->bounds) {
560	memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
561	lo_tcontext.type = target->bounds;
562	tcontextp = &lo_tcontext;
563	}
564
565	context_struct_compute_av(policydb, scontext: &lo_scontext,
566	tcontext: tcontextp,
567	tclass,
568	avd: &lo_avd,
569	NULL);
570
571	masked = ~lo_avd.allowed & avd->allowed;
572
573	if (likely(!masked))
574	return; /* no masked permission */
575
576	/* mask violated permissions */
577	avd->allowed &= ~masked;
578
579	/* audit masked permissions */
580	security_dump_masked_av(policydb, scontext, tcontext,
581	tclass, permissions: masked, reason: "bounds");
582	}
583
584	/*
585	* flag which drivers have permissions
586	* only looking for ioctl based extended permissions
587	*/
588	void services_compute_xperms_drivers(
589	struct extended_perms *xperms,
590	struct avtab_node *node)
591	{
592	unsigned int i;
593
594	if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
595	/* if one or more driver has all permissions allowed */
596	for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
597	xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
598	} else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
599	/* if allowing permissions within a driver */
600	security_xperm_set(xperms->drivers.p,
601	node->datum.u.xperms->driver);
602	}
603
604	xperms->len = 1;
605	}
606
607	/*
608	* Compute access vectors and extended permissions based on a context
609	* structure pair for the permissions in a particular class.
610	*/
611	static void context_struct_compute_av(struct policydb *policydb,
612	struct context *scontext,
613	struct context *tcontext,
614	u16 tclass,
615	struct av_decision *avd,
616	struct extended_perms *xperms)
617	{
618	struct constraint_node *constraint;
619	struct role_allow *ra;
620	struct avtab_key avkey;
621	struct avtab_node *node;
622	struct class_datum *tclass_datum;
623	struct ebitmap *sattr, *tattr;
624	struct ebitmap_node *snode, *tnode;
625	unsigned int i, j;
626
627	avd->allowed = 0;
628	avd->auditallow = 0;
629	avd->auditdeny = 0xffffffff;
630	if (xperms) {
631	memset(&xperms->drivers, 0, sizeof(xperms->drivers));
632	xperms->len = 0;
633	}
634
635	if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
636	if (printk_ratelimit())
637	pr_warn("SELinux: Invalid class %hu\n", tclass);
638	return;
639	}
640
641	tclass_datum = policydb->class_val_to_struct[tclass - 1];
642
643	/*
644	* If a specific type enforcement rule was defined for
645	* this permission check, then use it.
646	*/
647	avkey.target_class = tclass;
648	avkey.specified = AVTAB_AV | AVTAB_XPERMS;
649	sattr = &policydb->type_attr_map_array[scontext->type - 1];
650	tattr = &policydb->type_attr_map_array[tcontext->type - 1];
651	ebitmap_for_each_positive_bit(sattr, snode, i) {
652	ebitmap_for_each_positive_bit(tattr, tnode, j) {
653	avkey.source_type = i + 1;
654	avkey.target_type = j + 1;
655	for (node = avtab_search_node(h: &policydb->te_avtab,
656	key: &avkey);
657	node;
658	node = avtab_search_node_next(node, specified: avkey.specified)) {
659	if (node->key.specified == AVTAB_ALLOWED)
660	avd->allowed |= node->datum.u.data;
661	else if (node->key.specified == AVTAB_AUDITALLOW)
662	avd->auditallow |= node->datum.u.data;
663	else if (node->key.specified == AVTAB_AUDITDENY)
664	avd->auditdeny &= node->datum.u.data;
665	else if (xperms && (node->key.specified & AVTAB_XPERMS))
666	services_compute_xperms_drivers(xperms, node);
667	}
668
669	/* Check conditional av table for additional permissions */
670	cond_compute_av(ctab: &policydb->te_cond_avtab, key: &avkey,
671	avd, xperms);
672
673	}
674	}
675
676	/*
677	* Remove any permissions prohibited by a constraint (this includes
678	* the MLS policy).
679	*/
680	constraint = tclass_datum->constraints;
681	while (constraint) {
682	if ((constraint->permissions & (avd->allowed)) &&
683	!constraint_expr_eval(policydb, scontext, tcontext, NULL,
684	cexpr: constraint->expr)) {
685	avd->allowed &= ~(constraint->permissions);
686	}
687	constraint = constraint->next;
688	}
689
690	/*
691	* If checking process transition permission and the
692	* role is changing, then check the (current_role, new_role)
693	* pair.
694	*/
695	if (tclass == policydb->process_class &&
696	(avd->allowed & policydb->process_trans_perms) &&
697	scontext->role != tcontext->role) {
698	for (ra = policydb->role_allow; ra; ra = ra->next) {
699	if (scontext->role == ra->role &&
700	tcontext->role == ra->new_role)
701	break;
702	}
703	if (!ra)
704	avd->allowed &= ~policydb->process_trans_perms;
705	}
706
707	/*
708	* If the given source and target types have boundary
709	* constraint, lazy checks have to mask any violated
710	* permission and notice it to userspace via audit.
711	*/
712	type_attribute_bounds_av(policydb, scontext, tcontext,
713	tclass, avd);
714	}
715
716	static int security_validtrans_handle_fail(struct selinux_policy *policy,
717	struct sidtab_entry *oentry,
718	struct sidtab_entry *nentry,
719	struct sidtab_entry *tentry,
720	u16 tclass)
721	{
722	struct policydb *p = &policy->policydb;
723	struct sidtab *sidtab = policy->sidtab;
724	char *o = NULL, *n = NULL, *t = NULL;
725	u32 olen, nlen, tlen;
726
727	if (sidtab_entry_to_string(policydb: p, sidtab, entry: oentry, scontext: &o, scontext_len: &olen))
728	goto out;
729	if (sidtab_entry_to_string(policydb: p, sidtab, entry: nentry, scontext: &n, scontext_len: &nlen))
730	goto out;
731	if (sidtab_entry_to_string(policydb: p, sidtab, entry: tentry, scontext: &t, scontext_len: &tlen))
732	goto out;
733	audit_log(ctx: audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
734	fmt: "op=security_validate_transition seresult=denied"
735	" oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
736	o, n, t, sym_name(p, SYM_CLASSES, element_nr: tclass-1));
737	out:
738	kfree(objp: o);
739	kfree(objp: n);
740	kfree(objp: t);
741
742	if (!enforcing_enabled())
743	return 0;
744	return -EPERM;
745	}
746
747	static int security_compute_validatetrans(u32 oldsid, u32 newsid, u32 tasksid,
748	u16 orig_tclass, bool user)
749	{
750	struct selinux_policy *policy;
751	struct policydb *policydb;
752	struct sidtab *sidtab;
753	struct sidtab_entry *oentry;
754	struct sidtab_entry *nentry;
755	struct sidtab_entry *tentry;
756	struct class_datum *tclass_datum;
757	struct constraint_node *constraint;
758	u16 tclass;
759	int rc = 0;
760
761
762	if (!selinux_initialized())
763	return 0;
764
765	rcu_read_lock();
766
767	policy = rcu_dereference(selinux_state.policy);
768	policydb = &policy->policydb;
769	sidtab = policy->sidtab;
770
771	if (!user)
772	tclass = unmap_class(map: &policy->map, tclass: orig_tclass);
773	else
774	tclass = orig_tclass;
775
776	if (!tclass || tclass > policydb->p_classes.nprim) {
777	rc = -EINVAL;
778	goto out;
779	}
780	tclass_datum = policydb->class_val_to_struct[tclass - 1];
781
782	oentry = sidtab_search_entry(s: sidtab, sid: oldsid);
783	if (!oentry) {
784	pr_err("SELinux: %s: unrecognized SID %d\n",
785	__func__, oldsid);
786	rc = -EINVAL;
787	goto out;
788	}
789
790	nentry = sidtab_search_entry(s: sidtab, sid: newsid);
791	if (!nentry) {
792	pr_err("SELinux: %s: unrecognized SID %d\n",
793	__func__, newsid);
794	rc = -EINVAL;
795	goto out;
796	}
797
798	tentry = sidtab_search_entry(s: sidtab, sid: tasksid);
799	if (!tentry) {
800	pr_err("SELinux: %s: unrecognized SID %d\n",
801	__func__, tasksid);
802	rc = -EINVAL;
803	goto out;
804	}
805
806	constraint = tclass_datum->validatetrans;
807	while (constraint) {
808	if (!constraint_expr_eval(policydb, scontext: &oentry->context,
809	tcontext: &nentry->context, xcontext: &tentry->context,
810	cexpr: constraint->expr)) {
811	if (user)
812	rc = -EPERM;
813	else
814	rc = security_validtrans_handle_fail(policy,
815	oentry,
816	nentry,
817	tentry,
818	tclass);
819	goto out;
820	}
821	constraint = constraint->next;
822	}
823
824	out:
825	rcu_read_unlock();
826	return rc;
827	}
828
829	int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid,
830	u16 tclass)
831	{
832	return security_compute_validatetrans(oldsid, newsid, tasksid,
833	orig_tclass: tclass, user: true);
834	}
835
836	int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
837	u16 orig_tclass)
838	{
839	return security_compute_validatetrans(oldsid, newsid, tasksid,
840	orig_tclass, user: false);
841	}
842
843	/*
844	* security_bounded_transition - check whether the given
845	* transition is directed to bounded, or not.
846	* It returns 0, if @newsid is bounded by @oldsid.
847	* Otherwise, it returns error code.
848	*
849	* @oldsid : current security identifier
850	* @newsid : destinated security identifier
851	*/
852	int security_bounded_transition(u32 old_sid, u32 new_sid)
853	{
854	struct selinux_policy *policy;
855	struct policydb *policydb;
856	struct sidtab *sidtab;
857	struct sidtab_entry *old_entry, *new_entry;
858	struct type_datum *type;
859	u32 index;
860	int rc;
861
862	if (!selinux_initialized())
863	return 0;
864
865	rcu_read_lock();
866	policy = rcu_dereference(selinux_state.policy);
867	policydb = &policy->policydb;
868	sidtab = policy->sidtab;
869
870	rc = -EINVAL;
871	old_entry = sidtab_search_entry(s: sidtab, sid: old_sid);
872	if (!old_entry) {
873	pr_err("SELinux: %s: unrecognized SID %u\n",
874	__func__, old_sid);
875	goto out;
876	}
877
878	rc = -EINVAL;
879	new_entry = sidtab_search_entry(s: sidtab, sid: new_sid);
880	if (!new_entry) {
881	pr_err("SELinux: %s: unrecognized SID %u\n",
882	__func__, new_sid);
883	goto out;
884	}
885
886	rc = 0;
887	/* type/domain unchanged */
888	if (old_entry->context.type == new_entry->context.type)
889	goto out;
890
891	index = new_entry->context.type;
892	while (true) {
893	type = policydb->type_val_to_struct[index - 1];
894	BUG_ON(!type);
895
896	/* not bounded anymore */
897	rc = -EPERM;
898	if (!type->bounds)
899	break;
900
901	/* @newsid is bounded by @oldsid */
902	rc = 0;
903	if (type->bounds == old_entry->context.type)
904	break;
905
906	index = type->bounds;
907	}
908
909	if (rc) {
910	char *old_name = NULL;
911	char *new_name = NULL;
912	u32 length;
913
914	if (!sidtab_entry_to_string(policydb, sidtab, entry: old_entry,
915	scontext: &old_name, scontext_len: &length) &&
916	!sidtab_entry_to_string(policydb, sidtab, entry: new_entry,
917	scontext: &new_name, scontext_len: &length)) {
918	audit_log(ctx: audit_context(),
919	GFP_ATOMIC, AUDIT_SELINUX_ERR,
920	fmt: "op=security_bounded_transition "
921	"seresult=denied "
922	"oldcontext=%s newcontext=%s",
923	old_name, new_name);
924	}
925	kfree(objp: new_name);
926	kfree(objp: old_name);
927	}
928	out:
929	rcu_read_unlock();
930
931	return rc;
932	}
933
934	static void avd_init(struct selinux_policy *policy, struct av_decision *avd)
935	{
936	avd->allowed = 0;
937	avd->auditallow = 0;
938	avd->auditdeny = 0xffffffff;
939	if (policy)
940	avd->seqno = policy->latest_granting;
941	else
942	avd->seqno = 0;
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	struct selinux_policy *policy;
1007	struct policydb *policydb;
1008	struct sidtab *sidtab;
1009	u16 tclass;
1010	struct context *scontext, *tcontext;
1011	struct avtab_key avkey;
1012	struct avtab_node *node;
1013	struct ebitmap *sattr, *tattr;
1014	struct ebitmap_node *snode, *tnode;
1015	unsigned int i, j;
1016
1017	xpermd->driver = driver;
1018	xpermd->used = 0;
1019	memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1020	memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1021	memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1022
1023	rcu_read_lock();
1024	if (!selinux_initialized())
1025	goto allow;
1026
1027	policy = rcu_dereference(selinux_state.policy);
1028	policydb = &policy->policydb;
1029	sidtab = policy->sidtab;
1030
1031	scontext = sidtab_search(s: sidtab, sid: ssid);
1032	if (!scontext) {
1033	pr_err("SELinux: %s: unrecognized SID %d\n",
1034	__func__, ssid);
1035	goto out;
1036	}
1037
1038	tcontext = sidtab_search(s: sidtab, sid: tsid);
1039	if (!tcontext) {
1040	pr_err("SELinux: %s: unrecognized SID %d\n",
1041	__func__, tsid);
1042	goto out;
1043	}
1044
1045	tclass = unmap_class(map: &policy->map, tclass: orig_tclass);
1046	if (unlikely(orig_tclass && !tclass)) {
1047	if (policydb->allow_unknown)
1048	goto allow;
1049	goto out;
1050	}
1051
1052
1053	if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1054	pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1055	goto out;
1056	}
1057
1058	avkey.target_class = tclass;
1059	avkey.specified = AVTAB_XPERMS;
1060	sattr = &policydb->type_attr_map_array[scontext->type - 1];
1061	tattr = &policydb->type_attr_map_array[tcontext->type - 1];
1062	ebitmap_for_each_positive_bit(sattr, snode, i) {
1063	ebitmap_for_each_positive_bit(tattr, tnode, j) {
1064	avkey.source_type = i + 1;
1065	avkey.target_type = j + 1;
1066	for (node = avtab_search_node(h: &policydb->te_avtab,
1067	key: &avkey);
1068	node;
1069	node = avtab_search_node_next(node, specified: avkey.specified))
1070	services_compute_xperms_decision(xpermd, node);
1071
1072	cond_compute_xperms(ctab: &policydb->te_cond_avtab,
1073	key: &avkey, xpermd);
1074	}
1075	}
1076	out:
1077	rcu_read_unlock();
1078	return;
1079	allow:
1080	memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1081	goto out;
1082	}
1083
1084	/**
1085	* security_compute_av - Compute access vector decisions.
1086	* @ssid: source security identifier
1087	* @tsid: target security identifier
1088	* @orig_tclass: target security class
1089	* @avd: access vector decisions
1090	* @xperms: extended permissions
1091	*
1092	* Compute a set of access vector decisions based on the
1093	* SID pair (@ssid, @tsid) for the permissions in @tclass.
1094	*/
1095	void security_compute_av(u32 ssid,
1096	u32 tsid,
1097	u16 orig_tclass,
1098	struct av_decision *avd,
1099	struct extended_perms *xperms)
1100	{
1101	struct selinux_policy *policy;
1102	struct policydb *policydb;
1103	struct sidtab *sidtab;
1104	u16 tclass;
1105	struct context *scontext = NULL, *tcontext = NULL;
1106
1107	rcu_read_lock();
1108	policy = rcu_dereference(selinux_state.policy);
1109	avd_init(policy, avd);
1110	xperms->len = 0;
1111	if (!selinux_initialized())
1112	goto allow;
1113
1114	policydb = &policy->policydb;
1115	sidtab = policy->sidtab;
1116
1117	scontext = sidtab_search(s: sidtab, sid: ssid);
1118	if (!scontext) {
1119	pr_err("SELinux: %s: unrecognized SID %d\n",
1120	__func__, ssid);
1121	goto out;
1122	}
1123
1124	/* permissive domain? */
1125	if (ebitmap_get_bit(e: &policydb->permissive_map, bit: scontext->type))
1126	avd->flags |= AVD_FLAGS_PERMISSIVE;
1127
1128	tcontext = sidtab_search(s: sidtab, sid: tsid);
1129	if (!tcontext) {
1130	pr_err("SELinux: %s: unrecognized SID %d\n",
1131	__func__, tsid);
1132	goto out;
1133	}
1134
1135	tclass = unmap_class(map: &policy->map, tclass: orig_tclass);
1136	if (unlikely(orig_tclass && !tclass)) {
1137	if (policydb->allow_unknown)
1138	goto allow;
1139	goto out;
1140	}
1141	context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1142	xperms);
1143	map_decision(map: &policy->map, tclass: orig_tclass, avd,
1144	allow_unknown: policydb->allow_unknown);
1145	out:
1146	rcu_read_unlock();
1147	return;
1148	allow:
1149	avd->allowed = 0xffffffff;
1150	goto out;
1151	}
1152
1153	void security_compute_av_user(u32 ssid,
1154	u32 tsid,
1155	u16 tclass,
1156	struct av_decision *avd)
1157	{
1158	struct selinux_policy *policy;
1159	struct policydb *policydb;
1160	struct sidtab *sidtab;
1161	struct context *scontext = NULL, *tcontext = NULL;
1162
1163	rcu_read_lock();
1164	policy = rcu_dereference(selinux_state.policy);
1165	avd_init(policy, avd);
1166	if (!selinux_initialized())
1167	goto allow;
1168
1169	policydb = &policy->policydb;
1170	sidtab = policy->sidtab;
1171
1172	scontext = sidtab_search(s: sidtab, sid: ssid);
1173	if (!scontext) {
1174	pr_err("SELinux: %s: unrecognized SID %d\n",
1175	__func__, ssid);
1176	goto out;
1177	}
1178
1179	/* permissive domain? */
1180	if (ebitmap_get_bit(e: &policydb->permissive_map, bit: scontext->type))
1181	avd->flags |= AVD_FLAGS_PERMISSIVE;
1182
1183	tcontext = sidtab_search(s: sidtab, sid: tsid);
1184	if (!tcontext) {
1185	pr_err("SELinux: %s: unrecognized SID %d\n",
1186	__func__, tsid);
1187	goto out;
1188	}
1189
1190	if (unlikely(!tclass)) {
1191	if (policydb->allow_unknown)
1192	goto allow;
1193	goto out;
1194	}
1195
1196	context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1197	NULL);
1198	out:
1199	rcu_read_unlock();
1200	return;
1201	allow:
1202	avd->allowed = 0xffffffff;
1203	goto out;
1204	}
1205
1206	/*
1207	* Write the security context string representation of
1208	* the context structure `context' into a dynamically
1209	* allocated string of the correct size. Set `*scontext'
1210	* to point to this string and set `*scontext_len' to
1211	* the length of the string.
1212	*/
1213	static int context_struct_to_string(struct policydb *p,
1214	struct context *context,
1215	char **scontext, u32 *scontext_len)
1216	{
1217	char *scontextp;
1218
1219	if (scontext)
1220	*scontext = NULL;
1221	*scontext_len = 0;
1222
1223	if (context->len) {
1224	*scontext_len = context->len;
1225	if (scontext) {
1226	*scontext = kstrdup(s: context->str, GFP_ATOMIC);
1227	if (!(*scontext))
1228	return -ENOMEM;
1229	}
1230	return 0;
1231	}
1232
1233	/* Compute the size of the context. */
1234	*scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1235	*scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1236	*scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1237	*scontext_len += mls_compute_context_len(p, context);
1238
1239	if (!scontext)
1240	return 0;
1241
1242	/* Allocate space for the context; caller must free this space. */
1243	scontextp = kmalloc(size: *scontext_len, GFP_ATOMIC);
1244	if (!scontextp)
1245	return -ENOMEM;
1246	*scontext = scontextp;
1247
1248	/*
1249	* Copy the user name, role name and type name into the context.
1250	*/
1251	scontextp += sprintf(buf: scontextp, fmt: "%s:%s:%s",
1252	sym_name(p, SYM_USERS, element_nr: context->user - 1),
1253	sym_name(p, SYM_ROLES, element_nr: context->role - 1),
1254	sym_name(p, SYM_TYPES, element_nr: context->type - 1));
1255
1256	mls_sid_to_context(p, context, scontext: &scontextp);
1257
1258	*scontextp = 0;
1259
1260	return 0;
1261	}
1262
1263	static int sidtab_entry_to_string(struct policydb *p,
1264	struct sidtab *sidtab,
1265	struct sidtab_entry *entry,
1266	char **scontext, u32 *scontext_len)
1267	{
1268	int rc = sidtab_sid2str_get(s: sidtab, entry, out: scontext, out_len: scontext_len);
1269
1270	if (rc != -ENOENT)
1271	return rc;
1272
1273	rc = context_struct_to_string(p, context: &entry->context, scontext,
1274	scontext_len);
1275	if (!rc && scontext)
1276	sidtab_sid2str_put(s: sidtab, entry, str: *scontext, str_len: *scontext_len);
1277	return rc;
1278	}
1279
1280	#include "initial_sid_to_string.h"
1281
1282	int security_sidtab_hash_stats(char *page)
1283	{
1284	struct selinux_policy *policy;
1285	int rc;
1286
1287	if (!selinux_initialized()) {
1288	pr_err("SELinux: %s: called before initial load_policy\n",
1289	__func__);
1290	return -EINVAL;
1291	}
1292
1293	rcu_read_lock();
1294	policy = rcu_dereference(selinux_state.policy);
1295	rc = sidtab_hash_stats(sidtab: policy->sidtab, page);
1296	rcu_read_unlock();
1297
1298	return rc;
1299	}
1300
1301	const char *security_get_initial_sid_context(u32 sid)
1302	{
1303	if (unlikely(sid > SECINITSID_NUM))
1304	return NULL;
1305	return initial_sid_to_string[sid];
1306	}
1307
1308	static int security_sid_to_context_core(u32 sid, char **scontext,
1309	u32 *scontext_len, int force,
1310	int only_invalid)
1311	{
1312	struct selinux_policy *policy;
1313	struct policydb *policydb;
1314	struct sidtab *sidtab;
1315	struct sidtab_entry *entry;
1316	int rc = 0;
1317
1318	if (scontext)
1319	*scontext = NULL;
1320	*scontext_len = 0;
1321
1322	if (!selinux_initialized()) {
1323	if (sid <= SECINITSID_NUM) {
1324	char *scontextp;
1325	const char *s = initial_sid_to_string[sid];
1326
1327	if (!s)
1328	return -EINVAL;
1329	*scontext_len = strlen(s) + 1;
1330	if (!scontext)
1331	return 0;
1332	scontextp = kmemdup(p: s, size: *scontext_len, GFP_ATOMIC);
1333	if (!scontextp)
1334	return -ENOMEM;
1335	*scontext = scontextp;
1336	return 0;
1337	}
1338	pr_err("SELinux: %s: called before initial "
1339	"load_policy on unknown SID %d\n", __func__, sid);
1340	return -EINVAL;
1341	}
1342	rcu_read_lock();
1343	policy = rcu_dereference(selinux_state.policy);
1344	policydb = &policy->policydb;
1345	sidtab = policy->sidtab;
1346
1347	if (force)
1348	entry = sidtab_search_entry_force(s: sidtab, sid);
1349	else
1350	entry = sidtab_search_entry(s: sidtab, sid);
1351	if (!entry) {
1352	pr_err("SELinux: %s: unrecognized SID %d\n",
1353	__func__, sid);
1354	rc = -EINVAL;
1355	goto out_unlock;
1356	}
1357	if (only_invalid && !entry->context.len)
1358	goto out_unlock;
1359
1360	rc = sidtab_entry_to_string(p: policydb, sidtab, entry, scontext,
1361	scontext_len);
1362
1363	out_unlock:
1364	rcu_read_unlock();
1365	return rc;
1366
1367	}
1368
1369	/**
1370	* security_sid_to_context - Obtain a context for a given SID.
1371	* @sid: security identifier, SID
1372	* @scontext: security context
1373	* @scontext_len: length in bytes
1374	*
1375	* Write the string representation of the context associated with @sid
1376	* into a dynamically allocated string of the correct size. Set @scontext
1377	* to point to this string and set @scontext_len to the length of the string.
1378	*/
1379	int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1380	{
1381	return security_sid_to_context_core(sid, scontext,
1382	scontext_len, force: 0, only_invalid: 0);
1383	}
1384
1385	int security_sid_to_context_force(u32 sid,
1386	char **scontext, u32 *scontext_len)
1387	{
1388	return security_sid_to_context_core(sid, scontext,
1389	scontext_len, force: 1, only_invalid: 0);
1390	}
1391
1392	/**
1393	* security_sid_to_context_inval - Obtain a context for a given SID if it
1394	* is invalid.
1395	* @sid: security identifier, SID
1396	* @scontext: security context
1397	* @scontext_len: length in bytes
1398	*
1399	* Write the string representation of the context associated with @sid
1400	* into a dynamically allocated string of the correct size, but only if the
1401	* context is invalid in the current policy. Set @scontext to point to
1402	* this string (or NULL if the context is valid) and set @scontext_len to
1403	* the length of the string (or 0 if the context is valid).
1404	*/
1405	int security_sid_to_context_inval(u32 sid,
1406	char **scontext, u32 *scontext_len)
1407	{
1408	return security_sid_to_context_core(sid, scontext,
1409	scontext_len, force: 1, only_invalid: 1);
1410	}
1411
1412	/*
1413	* Caveat: Mutates scontext.
1414	*/
1415	static int string_to_context_struct(struct policydb *pol,
1416	struct sidtab *sidtabp,
1417	char *scontext,
1418	struct context *ctx,
1419	u32 def_sid)
1420	{
1421	struct role_datum *role;
1422	struct type_datum *typdatum;
1423	struct user_datum *usrdatum;
1424	char *scontextp, *p, oldc;
1425	int rc = 0;
1426
1427	context_init(c: ctx);
1428
1429	/* Parse the security context. */
1430
1431	rc = -EINVAL;
1432	scontextp = scontext;
1433
1434	/* Extract the user. */
1435	p = scontextp;
1436	while (*p && *p != ':')
1437	p++;
1438
1439	if (*p == 0)
1440	goto out;
1441
1442	*p++ = 0;
1443
1444	usrdatum = symtab_search(s: &pol->p_users, name: scontextp);
1445	if (!usrdatum)
1446	goto out;
1447
1448	ctx->user = usrdatum->value;
1449
1450	/* Extract role. */
1451	scontextp = p;
1452	while (*p && *p != ':')
1453	p++;
1454
1455	if (*p == 0)
1456	goto out;
1457
1458	*p++ = 0;
1459
1460	role = symtab_search(s: &pol->p_roles, name: scontextp);
1461	if (!role)
1462	goto out;
1463	ctx->role = role->value;
1464
1465	/* Extract type. */
1466	scontextp = p;
1467	while (*p && *p != ':')
1468	p++;
1469	oldc = *p;
1470	*p++ = 0;
1471
1472	typdatum = symtab_search(s: &pol->p_types, name: scontextp);
1473	if (!typdatum || typdatum->attribute)
1474	goto out;
1475
1476	ctx->type = typdatum->value;
1477
1478	rc = mls_context_to_sid(p: pol, oldc, scontext: p, context: ctx, s: sidtabp, def_sid);
1479	if (rc)
1480	goto out;
1481
1482	/* Check the validity of the new context. */
1483	rc = -EINVAL;
1484	if (!policydb_context_isvalid(p: pol, c: ctx))
1485	goto out;
1486	rc = 0;
1487	out:
1488	if (rc)
1489	context_destroy(c: ctx);
1490	return rc;
1491	}
1492
1493	static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1494	u32 *sid, u32 def_sid, gfp_t gfp_flags,
1495	int force)
1496	{
1497	struct selinux_policy *policy;
1498	struct policydb *policydb;
1499	struct sidtab *sidtab;
1500	char *scontext2, *str = NULL;
1501	struct context context;
1502	int rc = 0;
1503
1504	/* An empty security context is never valid. */
1505	if (!scontext_len)
1506	return -EINVAL;
1507
1508	/* Copy the string to allow changes and ensure a NUL terminator */
1509	scontext2 = kmemdup_nul(s: scontext, len: scontext_len, gfp: gfp_flags);
1510	if (!scontext2)
1511	return -ENOMEM;
1512
1513	if (!selinux_initialized()) {
1514	u32 i;
1515
1516	for (i = 1; i < SECINITSID_NUM; i++) {
1517	const char *s = initial_sid_to_string[i];
1518
1519	if (s && !strcmp(s, scontext2)) {
1520	*sid = i;
1521	goto out;
1522	}
1523	}
1524	*sid = SECINITSID_KERNEL;
1525	goto out;
1526	}
1527	*sid = SECSID_NULL;
1528
1529	if (force) {
1530	/* Save another copy for storing in uninterpreted form */
1531	rc = -ENOMEM;
1532	str = kstrdup(s: scontext2, gfp: gfp_flags);
1533	if (!str)
1534	goto out;
1535	}
1536	retry:
1537	rcu_read_lock();
1538	policy = rcu_dereference(selinux_state.policy);
1539	policydb = &policy->policydb;
1540	sidtab = policy->sidtab;
1541	rc = string_to_context_struct(pol: policydb, sidtabp: sidtab, scontext: scontext2,
1542	ctx: &context, def_sid);
1543	if (rc == -EINVAL && force) {
1544	context.str = str;
1545	context.len = strlen(str) + 1;
1546	str = NULL;
1547	} else if (rc)
1548	goto out_unlock;
1549	rc = sidtab_context_to_sid(s: sidtab, context: &context, sid);
1550	if (rc == -ESTALE) {
1551	rcu_read_unlock();
1552	if (context.str) {
1553	str = context.str;
1554	context.str = NULL;
1555	}
1556	context_destroy(c: &context);
1557	goto retry;
1558	}
1559	context_destroy(c: &context);
1560	out_unlock:
1561	rcu_read_unlock();
1562	out:
1563	kfree(objp: scontext2);
1564	kfree(objp: str);
1565	return rc;
1566	}
1567
1568	/**
1569	* security_context_to_sid - Obtain a SID for a given security context.
1570	* @scontext: security context
1571	* @scontext_len: length in bytes
1572	* @sid: security identifier, SID
1573	* @gfp: context for the allocation
1574	*
1575	* Obtains a SID associated with the security context that
1576	* has the string representation specified by @scontext.
1577	* Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1578	* memory is available, or 0 on success.
1579	*/
1580	int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid,
1581	gfp_t gfp)
1582	{
1583	return security_context_to_sid_core(scontext, scontext_len,
1584	sid, SECSID_NULL, gfp_flags: gfp, force: 0);
1585	}
1586
1587	int security_context_str_to_sid(const char *scontext, u32 *sid, gfp_t gfp)
1588	{
1589	return security_context_to_sid(scontext, strlen(scontext),
1590	sid, gfp);
1591	}
1592
1593	/**
1594	* security_context_to_sid_default - Obtain a SID for a given security context,
1595	* falling back to specified default if needed.
1596	*
1597	* @scontext: security context
1598	* @scontext_len: length in bytes
1599	* @sid: security identifier, SID
1600	* @def_sid: default SID to assign on error
1601	* @gfp_flags: the allocator get-free-page (GFP) flags
1602	*
1603	* Obtains a SID associated with the security context that
1604	* has the string representation specified by @scontext.
1605	* The default SID is passed to the MLS layer to be used to allow
1606	* kernel labeling of the MLS field if the MLS field is not present
1607	* (for upgrading to MLS without full relabel).
1608	* Implicitly forces adding of the context even if it cannot be mapped yet.
1609	* Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1610	* memory is available, or 0 on success.
1611	*/
1612	int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1613	u32 *sid, u32 def_sid, gfp_t gfp_flags)
1614	{
1615	return security_context_to_sid_core(scontext, scontext_len,
1616	sid, def_sid, gfp_flags, force: 1);
1617	}
1618
1619	int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1620	u32 *sid)
1621	{
1622	return security_context_to_sid_core(scontext, scontext_len,
1623	sid, SECSID_NULL, GFP_KERNEL, force: 1);
1624	}
1625
1626	static int compute_sid_handle_invalid_context(
1627	struct selinux_policy *policy,
1628	struct sidtab_entry *sentry,
1629	struct sidtab_entry *tentry,
1630	u16 tclass,
1631	struct context *newcontext)
1632	{
1633	struct policydb *policydb = &policy->policydb;
1634	struct sidtab *sidtab = policy->sidtab;
1635	char *s = NULL, *t = NULL, *n = NULL;
1636	u32 slen, tlen, nlen;
1637	struct audit_buffer *ab;
1638
1639	if (sidtab_entry_to_string(p: policydb, sidtab, entry: sentry, scontext: &s, scontext_len: &slen))
1640	goto out;
1641	if (sidtab_entry_to_string(p: policydb, sidtab, entry: tentry, scontext: &t, scontext_len: &tlen))
1642	goto out;
1643	if (context_struct_to_string(p: policydb, context: newcontext, scontext: &n, scontext_len: &nlen))
1644	goto out;
1645	ab = audit_log_start(ctx: audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR);
1646	if (!ab)
1647	goto out;
1648	audit_log_format(ab,
1649	fmt: "op=security_compute_sid invalid_context=");
1650	/* no need to record the NUL with untrusted strings */
1651	audit_log_n_untrustedstring(ab, string: n, n: nlen - 1);
1652	audit_log_format(ab, fmt: " scontext=%s tcontext=%s tclass=%s",
1653	s, t, sym_name(p: policydb, SYM_CLASSES, element_nr: tclass-1));
1654	audit_log_end(ab);
1655	out:
1656	kfree(objp: s);
1657	kfree(objp: t);
1658	kfree(objp: n);
1659	if (!enforcing_enabled())
1660	return 0;
1661	return -EACCES;
1662	}
1663
1664	static void filename_compute_type(struct policydb *policydb,
1665	struct context *newcontext,
1666	u32 stype, u32 ttype, u16 tclass,
1667	const char *objname)
1668	{
1669	struct filename_trans_key ft;
1670	struct filename_trans_datum *datum;
1671
1672	/*
1673	* Most filename trans rules are going to live in specific directories
1674	* like /dev or /var/run. This bitmap will quickly skip rule searches
1675	* if the ttype does not contain any rules.
1676	*/
1677	if (!ebitmap_get_bit(e: &policydb->filename_trans_ttypes, bit: ttype))
1678	return;
1679
1680	ft.ttype = ttype;
1681	ft.tclass = tclass;
1682	ft.name = objname;
1683
1684	datum = policydb_filenametr_search(p: policydb, key: &ft);
1685	while (datum) {
1686	if (ebitmap_get_bit(e: &datum->stypes, bit: stype - 1)) {
1687	newcontext->type = datum->otype;
1688	return;
1689	}
1690	datum = datum->next;
1691	}
1692	}
1693
1694	static int security_compute_sid(u32 ssid,
1695	u32 tsid,
1696	u16 orig_tclass,
1697	u16 specified,
1698	const char *objname,
1699	u32 *out_sid,
1700	bool kern)
1701	{
1702	struct selinux_policy *policy;
1703	struct policydb *policydb;
1704	struct sidtab *sidtab;
1705	struct class_datum *cladatum;
1706	struct context *scontext, *tcontext, newcontext;
1707	struct sidtab_entry *sentry, *tentry;
1708	struct avtab_key avkey;
1709	struct avtab_node *avnode, *node;
1710	u16 tclass;
1711	int rc = 0;
1712	bool sock;
1713
1714	if (!selinux_initialized()) {
1715	switch (orig_tclass) {
1716	case SECCLASS_PROCESS: /* kernel value */
1717	*out_sid = ssid;
1718	break;
1719	default:
1720	*out_sid = tsid;
1721	break;
1722	}
1723	goto out;
1724	}
1725
1726	retry:
1727	cladatum = NULL;
1728	context_init(c: &newcontext);
1729
1730	rcu_read_lock();
1731
1732	policy = rcu_dereference(selinux_state.policy);
1733
1734	if (kern) {
1735	tclass = unmap_class(map: &policy->map, tclass: orig_tclass);
1736	sock = security_is_socket_class(orig_tclass);
1737	} else {
1738	tclass = orig_tclass;
1739	sock = security_is_socket_class(map_class(map: &policy->map,
1740	pol_value: tclass));
1741	}
1742
1743	policydb = &policy->policydb;
1744	sidtab = policy->sidtab;
1745
1746	sentry = sidtab_search_entry(s: sidtab, sid: ssid);
1747	if (!sentry) {
1748	pr_err("SELinux: %s: unrecognized SID %d\n",
1749	__func__, ssid);
1750	rc = -EINVAL;
1751	goto out_unlock;
1752	}
1753	tentry = sidtab_search_entry(s: sidtab, sid: tsid);
1754	if (!tentry) {
1755	pr_err("SELinux: %s: unrecognized SID %d\n",
1756	__func__, tsid);
1757	rc = -EINVAL;
1758	goto out_unlock;
1759	}
1760
1761	scontext = &sentry->context;
1762	tcontext = &tentry->context;
1763
1764	if (tclass && tclass <= policydb->p_classes.nprim)
1765	cladatum = policydb->class_val_to_struct[tclass - 1];
1766
1767	/* Set the user identity. */
1768	switch (specified) {
1769	case AVTAB_TRANSITION:
1770	case AVTAB_CHANGE:
1771	if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1772	newcontext.user = tcontext->user;
1773	} else {
1774	/* notice this gets both DEFAULT_SOURCE and unset */
1775	/* Use the process user identity. */
1776	newcontext.user = scontext->user;
1777	}
1778	break;
1779	case AVTAB_MEMBER:
1780	/* Use the related object owner. */
1781	newcontext.user = tcontext->user;
1782	break;
1783	}
1784
1785	/* Set the role to default values. */
1786	if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1787	newcontext.role = scontext->role;
1788	} else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1789	newcontext.role = tcontext->role;
1790	} else {
1791	if ((tclass == policydb->process_class) || sock)
1792	newcontext.role = scontext->role;
1793	else
1794	newcontext.role = OBJECT_R_VAL;
1795	}
1796
1797	/* Set the type to default values. */
1798	if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1799	newcontext.type = scontext->type;
1800	} else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1801	newcontext.type = tcontext->type;
1802	} else {
1803	if ((tclass == policydb->process_class) || sock) {
1804	/* Use the type of process. */
1805	newcontext.type = scontext->type;
1806	} else {
1807	/* Use the type of the related object. */
1808	newcontext.type = tcontext->type;
1809	}
1810	}
1811
1812	/* Look for a type transition/member/change rule. */
1813	avkey.source_type = scontext->type;
1814	avkey.target_type = tcontext->type;
1815	avkey.target_class = tclass;
1816	avkey.specified = specified;
1817	avnode = avtab_search_node(h: &policydb->te_avtab, key: &avkey);
1818
1819	/* If no permanent rule, also check for enabled conditional rules */
1820	if (!avnode) {
1821	node = avtab_search_node(h: &policydb->te_cond_avtab, key: &avkey);
1822	for (; node; node = avtab_search_node_next(node, specified)) {
1823	if (node->key.specified & AVTAB_ENABLED) {
1824	avnode = node;
1825	break;
1826	}
1827	}
1828	}
1829
1830	if (avnode) {
1831	/* Use the type from the type transition/member/change rule. */
1832	newcontext.type = avnode->datum.u.data;
1833	}
1834
1835	/* if we have a objname this is a file trans check so check those rules */
1836	if (objname)
1837	filename_compute_type(policydb, newcontext: &newcontext, stype: scontext->type,
1838	ttype: tcontext->type, tclass, objname);
1839
1840	/* Check for class-specific changes. */
1841	if (specified & AVTAB_TRANSITION) {
1842	/* Look for a role transition rule. */
1843	struct role_trans_datum *rtd;
1844	struct role_trans_key rtk = {
1845	.role = scontext->role,
1846	.type = tcontext->type,
1847	.tclass = tclass,
1848	};
1849
1850	rtd = policydb_roletr_search(p: policydb, key: &rtk);
1851	if (rtd)
1852	newcontext.role = rtd->new_role;
1853	}
1854
1855	/* Set the MLS attributes.
1856	This is done last because it may allocate memory. */
1857	rc = mls_compute_sid(p: policydb, scontext, tcontext, tclass, specified,
1858	newcontext: &newcontext, sock);
1859	if (rc)
1860	goto out_unlock;
1861
1862	/* Check the validity of the context. */
1863	if (!policydb_context_isvalid(p: policydb, c: &newcontext)) {
1864	rc = compute_sid_handle_invalid_context(policy, sentry,
1865	tentry, tclass,
1866	newcontext: &newcontext);
1867	if (rc)
1868	goto out_unlock;
1869	}
1870	/* Obtain the sid for the context. */
1871	rc = sidtab_context_to_sid(s: sidtab, context: &newcontext, sid: out_sid);
1872	if (rc == -ESTALE) {
1873	rcu_read_unlock();
1874	context_destroy(c: &newcontext);
1875	goto retry;
1876	}
1877	out_unlock:
1878	rcu_read_unlock();
1879	context_destroy(c: &newcontext);
1880	out:
1881	return rc;
1882	}
1883
1884	/**
1885	* security_transition_sid - Compute the SID for a new subject/object.
1886	* @ssid: source security identifier
1887	* @tsid: target security identifier
1888	* @tclass: target security class
1889	* @qstr: object name
1890	* @out_sid: security identifier for new subject/object
1891	*
1892	* Compute a SID to use for labeling a new subject or object in the
1893	* class @tclass based on a SID pair (@ssid, @tsid).
1894	* Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1895	* if insufficient memory is available, or %0 if the new SID was
1896	* computed successfully.
1897	*/
1898	int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1899	const struct qstr *qstr, u32 *out_sid)
1900	{
1901	return security_compute_sid(ssid, tsid, orig_tclass: tclass,
1902	AVTAB_TRANSITION,
1903	objname: qstr ? qstr->name : NULL, out_sid, kern: true);
1904	}
1905
1906	int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1907	const char *objname, u32 *out_sid)
1908	{
1909	return security_compute_sid(ssid, tsid, orig_tclass: tclass,
1910	AVTAB_TRANSITION,
1911	objname, out_sid, kern: false);
1912	}
1913
1914	/**
1915	* security_member_sid - Compute the SID for member selection.
1916	* @ssid: source security identifier
1917	* @tsid: target security identifier
1918	* @tclass: target security class
1919	* @out_sid: security identifier for selected member
1920	*
1921	* Compute a SID to use when selecting a member of a polyinstantiated
1922	* object of class @tclass based on a SID pair (@ssid, @tsid).
1923	* Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1924	* if insufficient memory is available, or %0 if the SID was
1925	* computed successfully.
1926	*/
1927	int security_member_sid(u32 ssid,
1928	u32 tsid,
1929	u16 tclass,
1930	u32 *out_sid)
1931	{
1932	return security_compute_sid(ssid, tsid, orig_tclass: tclass,
1933	AVTAB_MEMBER, NULL,
1934	out_sid, kern: false);
1935	}
1936
1937	/**
1938	* security_change_sid - Compute the SID for object relabeling.
1939	* @ssid: source security identifier
1940	* @tsid: target security identifier
1941	* @tclass: target security class
1942	* @out_sid: security identifier for selected member
1943	*
1944	* Compute a SID to use for relabeling an object of class @tclass
1945	* based on a SID pair (@ssid, @tsid).
1946	* Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1947	* if insufficient memory is available, or %0 if the SID was
1948	* computed successfully.
1949	*/
1950	int security_change_sid(u32 ssid,
1951	u32 tsid,
1952	u16 tclass,
1953	u32 *out_sid)
1954	{
1955	return security_compute_sid(ssid, tsid, orig_tclass: tclass, AVTAB_CHANGE, NULL,
1956	out_sid, kern: false);
1957	}
1958
1959	static inline int convert_context_handle_invalid_context(
1960	struct policydb *policydb,
1961	struct context *context)
1962	{
1963	char *s;
1964	u32 len;
1965
1966	if (enforcing_enabled())
1967	return -EINVAL;
1968
1969	if (!context_struct_to_string(p: policydb, context, scontext: &s, scontext_len: &len)) {
1970	pr_warn("SELinux: Context %s would be invalid if enforcing\n",
1971	s);
1972	kfree(objp: s);
1973	}
1974	return 0;
1975	}
1976
1977	/**
1978	* services_convert_context - Convert a security context across policies.
1979	* @args: populated convert_context_args struct
1980	* @oldc: original context
1981	* @newc: converted context
1982	* @gfp_flags: allocation flags
1983	*
1984	* Convert the values in the security context structure @oldc from the values
1985	* specified in the policy @args->oldp to the values specified in the policy
1986	* @args->newp, storing the new context in @newc, and verifying that the
1987	* context is valid under the new policy.
1988	*/
1989	int services_convert_context(struct convert_context_args *args,
1990	struct context *oldc, struct context *newc,
1991	gfp_t gfp_flags)
1992	{
1993	struct ocontext *oc;
1994	struct role_datum *role;
1995	struct type_datum *typdatum;
1996	struct user_datum *usrdatum;
1997	char *s;
1998	u32 len;
1999	int rc;
2000
2001	if (oldc->str) {
2002	s = kstrdup(s: oldc->str, gfp: gfp_flags);
2003	if (!s)
2004	return -ENOMEM;
2005
2006	rc = string_to_context_struct(pol: args->newp, NULL, scontext: s, ctx: newc, SECSID_NULL);
2007	if (rc == -EINVAL) {
2008	/*
2009	* Retain string representation for later mapping.
2010	*
2011	* IMPORTANT: We need to copy the contents of oldc->str
2012	* back into s again because string_to_context_struct()
2013	* may have garbled it.
2014	*/
2015	memcpy(s, oldc->str, oldc->len);
2016	context_init(c: newc);
2017	newc->str = s;
2018	newc->len = oldc->len;
2019	return 0;
2020	}
2021	kfree(objp: s);
2022	if (rc) {
2023	/* Other error condition, e.g. ENOMEM. */
2024	pr_err("SELinux: Unable to map context %s, rc = %d.\n",
2025	oldc->str, -rc);
2026	return rc;
2027	}
2028	pr_info("SELinux: Context %s became valid (mapped).\n",
2029	oldc->str);
2030	return 0;
2031	}
2032
2033	context_init(c: newc);
2034
2035	/* Convert the user. */
2036	usrdatum = symtab_search(s: &args->newp->p_users,
2037	name: sym_name(p: args->oldp, SYM_USERS, element_nr: oldc->user - 1));
2038	if (!usrdatum)
2039	goto bad;
2040	newc->user = usrdatum->value;
2041
2042	/* Convert the role. */
2043	role = symtab_search(s: &args->newp->p_roles,
2044	name: sym_name(p: args->oldp, SYM_ROLES, element_nr: oldc->role - 1));
2045	if (!role)
2046	goto bad;
2047	newc->role = role->value;
2048
2049	/* Convert the type. */
2050	typdatum = symtab_search(s: &args->newp->p_types,
2051	name: sym_name(p: args->oldp, SYM_TYPES, element_nr: oldc->type - 1));
2052	if (!typdatum)
2053	goto bad;
2054	newc->type = typdatum->value;
2055
2056	/* Convert the MLS fields if dealing with MLS policies */
2057	if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2058	rc = mls_convert_context(oldp: args->oldp, newp: args->newp, oldc, newc);
2059	if (rc)
2060	goto bad;
2061	} else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2062	/*
2063	* Switching between non-MLS and MLS policy:
2064	* ensure that the MLS fields of the context for all
2065	* existing entries in the sidtab are filled in with a
2066	* suitable default value, likely taken from one of the
2067	* initial SIDs.
2068	*/
2069	oc = args->newp->ocontexts[OCON_ISID];
2070	while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2071	oc = oc->next;
2072	if (!oc) {
2073	pr_err("SELinux: unable to look up"
2074	" the initial SIDs list\n");
2075	goto bad;
2076	}
2077	rc = mls_range_set(context: newc, range: &oc->context[0].range);
2078	if (rc)
2079	goto bad;
2080	}
2081
2082	/* Check the validity of the new context. */
2083	if (!policydb_context_isvalid(p: args->newp, c: newc)) {
2084	rc = convert_context_handle_invalid_context(policydb: args->oldp, context: oldc);
2085	if (rc)
2086	goto bad;
2087	}
2088
2089	return 0;
2090	bad:
2091	/* Map old representation to string and save it. */
2092	rc = context_struct_to_string(p: args->oldp, context: oldc, scontext: &s, scontext_len: &len);
2093	if (rc)
2094	return rc;
2095	context_destroy(c: newc);
2096	newc->str = s;
2097	newc->len = len;
2098	pr_info("SELinux: Context %s became invalid (unmapped).\n",
2099	newc->str);
2100	return 0;
2101	}
2102
2103	static void security_load_policycaps(struct selinux_policy *policy)
2104	{
2105	struct policydb *p;
2106	unsigned int i;
2107	struct ebitmap_node *node;
2108
2109	p = &policy->policydb;
2110
2111	for (i = 0; i < ARRAY_SIZE(selinux_state.policycap); i++)
2112	WRITE_ONCE(selinux_state.policycap[i],
2113	ebitmap_get_bit(&p->policycaps, i));
2114
2115	for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2116	pr_info("SELinux: policy capability %s=%d\n",
2117	selinux_policycap_names[i],
2118	ebitmap_get_bit(&p->policycaps, i));
2119
2120	ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2121	if (i >= ARRAY_SIZE(selinux_policycap_names))
2122	pr_info("SELinux: unknown policy capability %u\n",
2123	i);
2124	}
2125	}
2126
2127	static int security_preserve_bools(struct selinux_policy *oldpolicy,
2128	struct selinux_policy *newpolicy);
2129
2130	static void selinux_policy_free(struct selinux_policy *policy)
2131	{
2132	if (!policy)
2133	return;
2134
2135	sidtab_destroy(s: policy->sidtab);
2136	kfree(objp: policy->map.mapping);
2137	policydb_destroy(p: &policy->policydb);
2138	kfree(objp: policy->sidtab);
2139	kfree(objp: policy);
2140	}
2141
2142	static void selinux_policy_cond_free(struct selinux_policy *policy)
2143	{
2144	cond_policydb_destroy_dup(p: &policy->policydb);
2145	kfree(objp: policy);
2146	}
2147
2148	void selinux_policy_cancel(struct selinux_load_state *load_state)
2149	{
2150	struct selinux_state *state = &selinux_state;
2151	struct selinux_policy *oldpolicy;
2152
2153	oldpolicy = rcu_dereference_protected(state->policy,
2154	lockdep_is_held(&state->policy_mutex));
2155
2156	sidtab_cancel_convert(s: oldpolicy->sidtab);
2157	selinux_policy_free(policy: load_state->policy);
2158	kfree(objp: load_state->convert_data);
2159	}
2160
2161	static void selinux_notify_policy_change(u32 seqno)
2162	{
2163	/* Flush external caches and notify userspace of policy load */
2164	avc_ss_reset(seqno);
2165	selnl_notify_policyload(seqno);
2166	selinux_status_update_policyload(seqno);
2167	selinux_netlbl_cache_invalidate();
2168	selinux_xfrm_notify_policyload();
2169	selinux_ima_measure_state_locked();
2170	}
2171
2172	void selinux_policy_commit(struct selinux_load_state *load_state)
2173	{
2174	struct selinux_state *state = &selinux_state;
2175	struct selinux_policy *oldpolicy, *newpolicy = load_state->policy;
2176	unsigned long flags;
2177	u32 seqno;
2178
2179	oldpolicy = rcu_dereference_protected(state->policy,
2180	lockdep_is_held(&state->policy_mutex));
2181
2182	/* If switching between different policy types, log MLS status */
2183	if (oldpolicy) {
2184	if (oldpolicy->policydb.mls_enabled && !newpolicy->policydb.mls_enabled)
2185	pr_info("SELinux: Disabling MLS support...\n");
2186	else if (!oldpolicy->policydb.mls_enabled && newpolicy->policydb.mls_enabled)
2187	pr_info("SELinux: Enabling MLS support...\n");
2188	}
2189
2190	/* Set latest granting seqno for new policy. */
2191	if (oldpolicy)
2192	newpolicy->latest_granting = oldpolicy->latest_granting + 1;
2193	else
2194	newpolicy->latest_granting = 1;
2195	seqno = newpolicy->latest_granting;
2196
2197	/* Install the new policy. */
2198	if (oldpolicy) {
2199	sidtab_freeze_begin(s: oldpolicy->sidtab, flags: &flags);
2200	rcu_assign_pointer(state->policy, newpolicy);
2201	sidtab_freeze_end(s: oldpolicy->sidtab, flags: &flags);
2202	} else {
2203	rcu_assign_pointer(state->policy, newpolicy);
2204	}
2205
2206	/* Load the policycaps from the new policy */
2207	security_load_policycaps(policy: newpolicy);
2208
2209	if (!selinux_initialized()) {
2210	/*
2211	* After first policy load, the security server is
2212	* marked as initialized and ready to handle requests and
2213	* any objects created prior to policy load are then labeled.
2214	*/
2215	selinux_mark_initialized();
2216	selinux_complete_init();
2217	}
2218
2219	/* Free the old policy */
2220	synchronize_rcu();
2221	selinux_policy_free(policy: oldpolicy);
2222	kfree(objp: load_state->convert_data);
2223
2224	/* Notify others of the policy change */
2225	selinux_notify_policy_change(seqno);
2226	}
2227
2228	/**
2229	* security_load_policy - Load a security policy configuration.
2230	* @data: binary policy data
2231	* @len: length of data in bytes
2232	* @load_state: policy load state
2233	*
2234	* Load a new set of security policy configuration data,
2235	* validate it and convert the SID table as necessary.
2236	* This function will flush the access vector cache after
2237	* loading the new policy.
2238	*/
2239	int security_load_policy(void *data, size_t len,
2240	struct selinux_load_state *load_state)
2241	{
2242	struct selinux_state *state = &selinux_state;
2243	struct selinux_policy *newpolicy, *oldpolicy;
2244	struct selinux_policy_convert_data *convert_data;
2245	int rc = 0;
2246	struct policy_file file = { data, len }, *fp = &file;
2247
2248	newpolicy = kzalloc(size: sizeof(*newpolicy), GFP_KERNEL);
2249	if (!newpolicy)
2250	return -ENOMEM;
2251
2252	newpolicy->sidtab = kzalloc(size: sizeof(*newpolicy->sidtab), GFP_KERNEL);
2253	if (!newpolicy->sidtab) {
2254	rc = -ENOMEM;
2255	goto err_policy;
2256	}
2257
2258	rc = policydb_read(p: &newpolicy->policydb, fp);
2259	if (rc)
2260	goto err_sidtab;
2261
2262	newpolicy->policydb.len = len;
2263	rc = selinux_set_mapping(pol: &newpolicy->policydb, map: secclass_map,
2264	out_map: &newpolicy->map);
2265	if (rc)
2266	goto err_policydb;
2267
2268	rc = policydb_load_isids(p: &newpolicy->policydb, s: newpolicy->sidtab);
2269	if (rc) {
2270	pr_err("SELinux: unable to load the initial SIDs\n");
2271	goto err_mapping;
2272	}
2273
2274	if (!selinux_initialized()) {
2275	/* First policy load, so no need to preserve state from old policy */
2276	load_state->policy = newpolicy;
2277	load_state->convert_data = NULL;
2278	return 0;
2279	}
2280
2281	oldpolicy = rcu_dereference_protected(state->policy,
2282	lockdep_is_held(&state->policy_mutex));
2283
2284	/* Preserve active boolean values from the old policy */
2285	rc = security_preserve_bools(oldpolicy, newpolicy);
2286	if (rc) {
2287	pr_err("SELinux: unable to preserve booleans\n");
2288	goto err_free_isids;
2289	}
2290
2291	/*
2292	* Convert the internal representations of contexts
2293	* in the new SID table.
2294	*/
2295
2296	convert_data = kmalloc(size: sizeof(*convert_data), GFP_KERNEL);
2297	if (!convert_data) {
2298	rc = -ENOMEM;
2299	goto err_free_isids;
2300	}
2301
2302	convert_data->args.oldp = &oldpolicy->policydb;
2303	convert_data->args.newp = &newpolicy->policydb;
2304
2305	convert_data->sidtab_params.args = &convert_data->args;
2306	convert_data->sidtab_params.target = newpolicy->sidtab;
2307
2308	rc = sidtab_convert(s: oldpolicy->sidtab, params: &convert_data->sidtab_params);
2309	if (rc) {
2310	pr_err("SELinux: unable to convert the internal"
2311	" representation of contexts in the new SID"
2312	" table\n");
2313	goto err_free_convert_data;
2314	}
2315
2316	load_state->policy = newpolicy;
2317	load_state->convert_data = convert_data;
2318	return 0;
2319
2320	err_free_convert_data:
2321	kfree(objp: convert_data);
2322	err_free_isids:
2323	sidtab_destroy(s: newpolicy->sidtab);
2324	err_mapping:
2325	kfree(objp: newpolicy->map.mapping);
2326	err_policydb:
2327	policydb_destroy(p: &newpolicy->policydb);
2328	err_sidtab:
2329	kfree(objp: newpolicy->sidtab);
2330	err_policy:
2331	kfree(objp: newpolicy);
2332
2333	return rc;
2334	}
2335
2336	/**
2337	* ocontext_to_sid - Helper to safely get sid for an ocontext
2338	* @sidtab: SID table
2339	* @c: ocontext structure
2340	* @index: index of the context entry (0 or 1)
2341	* @out_sid: pointer to the resulting SID value
2342	*
2343	* For all ocontexts except OCON_ISID the SID fields are populated
2344	* on-demand when needed. Since updating the SID value is an SMP-sensitive
2345	* operation, this helper must be used to do that safely.
2346	*
2347	* WARNING: This function may return -ESTALE, indicating that the caller
2348	* must retry the operation after re-acquiring the policy pointer!
2349	*/
2350	static int ocontext_to_sid(struct sidtab *sidtab, struct ocontext *c,
2351	size_t index, u32 *out_sid)
2352	{
2353	int rc;
2354	u32 sid;
2355
2356	/* Ensure the associated sidtab entry is visible to this thread. */
2357	sid = smp_load_acquire(&c->sid[index]);
2358	if (!sid) {
2359	rc = sidtab_context_to_sid(s: sidtab, context: &c->context[index], sid: &sid);
2360	if (rc)
2361	return rc;
2362
2363	/*
2364	* Ensure the new sidtab entry is visible to other threads
2365	* when they see the SID.
2366	*/
2367	smp_store_release(&c->sid[index], sid);
2368	}
2369	*out_sid = sid;
2370	return 0;
2371	}
2372
2373	/**
2374	* security_port_sid - Obtain the SID for a port.
2375	* @protocol: protocol number
2376	* @port: port number
2377	* @out_sid: security identifier
2378	*/
2379	int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
2380	{
2381	struct selinux_policy *policy;
2382	struct policydb *policydb;
2383	struct sidtab *sidtab;
2384	struct ocontext *c;
2385	int rc;
2386
2387	if (!selinux_initialized()) {
2388	*out_sid = SECINITSID_PORT;
2389	return 0;
2390	}
2391
2392	retry:
2393	rc = 0;
2394	rcu_read_lock();
2395	policy = rcu_dereference(selinux_state.policy);
2396	policydb = &policy->policydb;
2397	sidtab = policy->sidtab;
2398
2399	c = policydb->ocontexts[OCON_PORT];
2400	while (c) {
2401	if (c->u.port.protocol == protocol &&
2402	c->u.port.low_port <= port &&
2403	c->u.port.high_port >= port)
2404	break;
2405	c = c->next;
2406	}
2407
2408	if (c) {
2409	rc = ocontext_to_sid(sidtab, c, index: 0, out_sid);
2410	if (rc == -ESTALE) {
2411	rcu_read_unlock();
2412	goto retry;
2413	}
2414	if (rc)
2415	goto out;
2416	} else {
2417	*out_sid = SECINITSID_PORT;
2418	}
2419
2420	out:
2421	rcu_read_unlock();
2422	return rc;
2423	}
2424
2425	/**
2426	* security_ib_pkey_sid - Obtain the SID for a pkey.
2427	* @subnet_prefix: Subnet Prefix
2428	* @pkey_num: pkey number
2429	* @out_sid: security identifier
2430	*/
2431	int security_ib_pkey_sid(u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2432	{
2433	struct selinux_policy *policy;
2434	struct policydb *policydb;
2435	struct sidtab *sidtab;
2436	struct ocontext *c;
2437	int rc;
2438
2439	if (!selinux_initialized()) {
2440	*out_sid = SECINITSID_UNLABELED;
2441	return 0;
2442	}
2443
2444	retry:
2445	rc = 0;
2446	rcu_read_lock();
2447	policy = rcu_dereference(selinux_state.policy);
2448	policydb = &policy->policydb;
2449	sidtab = policy->sidtab;
2450
2451	c = policydb->ocontexts[OCON_IBPKEY];
2452	while (c) {
2453	if (c->u.ibpkey.low_pkey <= pkey_num &&
2454	c->u.ibpkey.high_pkey >= pkey_num &&
2455	c->u.ibpkey.subnet_prefix == subnet_prefix)
2456	break;
2457
2458	c = c->next;
2459	}
2460
2461	if (c) {
2462	rc = ocontext_to_sid(sidtab, c, index: 0, out_sid);
2463	if (rc == -ESTALE) {
2464	rcu_read_unlock();
2465	goto retry;
2466	}
2467	if (rc)
2468	goto out;
2469	} else
2470	*out_sid = SECINITSID_UNLABELED;
2471
2472	out:
2473	rcu_read_unlock();
2474	return rc;
2475	}
2476
2477	/**
2478	* security_ib_endport_sid - Obtain the SID for a subnet management interface.
2479	* @dev_name: device name
2480	* @port_num: port number
2481	* @out_sid: security identifier
2482	*/
2483	int security_ib_endport_sid(const char *dev_name, u8 port_num, u32 *out_sid)
2484	{
2485	struct selinux_policy *policy;
2486	struct policydb *policydb;
2487	struct sidtab *sidtab;
2488	struct ocontext *c;
2489	int rc;
2490
2491	if (!selinux_initialized()) {
2492	*out_sid = SECINITSID_UNLABELED;
2493	return 0;
2494	}
2495
2496	retry:
2497	rc = 0;
2498	rcu_read_lock();
2499	policy = rcu_dereference(selinux_state.policy);
2500	policydb = &policy->policydb;
2501	sidtab = policy->sidtab;
2502
2503	c = policydb->ocontexts[OCON_IBENDPORT];
2504	while (c) {
2505	if (c->u.ibendport.port == port_num &&
2506	!strncmp(c->u.ibendport.dev_name,
2507	dev_name,
2508	IB_DEVICE_NAME_MAX))
2509	break;
2510
2511	c = c->next;
2512	}
2513
2514	if (c) {
2515	rc = ocontext_to_sid(sidtab, c, index: 0, out_sid);
2516	if (rc == -ESTALE) {
2517	rcu_read_unlock();
2518	goto retry;
2519	}
2520	if (rc)
2521	goto out;
2522	} else
2523	*out_sid = SECINITSID_UNLABELED;
2524
2525	out:
2526	rcu_read_unlock();
2527	return rc;
2528	}
2529
2530	/**
2531	* security_netif_sid - Obtain the SID for a network interface.
2532	* @name: interface name
2533	* @if_sid: interface SID
2534	*/
2535	int security_netif_sid(char *name, u32 *if_sid)
2536	{
2537	struct selinux_policy *policy;
2538	struct policydb *policydb;
2539	struct sidtab *sidtab;
2540	int rc;
2541	struct ocontext *c;
2542
2543	if (!selinux_initialized()) {
2544	*if_sid = SECINITSID_NETIF;
2545	return 0;
2546	}
2547
2548	retry:
2549	rc = 0;
2550	rcu_read_lock();
2551	policy = rcu_dereference(selinux_state.policy);
2552	policydb = &policy->policydb;
2553	sidtab = policy->sidtab;
2554
2555	c = policydb->ocontexts[OCON_NETIF];
2556	while (c) {
2557	if (strcmp(name, c->u.name) == 0)
2558	break;
2559	c = c->next;
2560	}
2561
2562	if (c) {
2563	rc = ocontext_to_sid(sidtab, c, index: 0, out_sid: if_sid);
2564	if (rc == -ESTALE) {
2565	rcu_read_unlock();
2566	goto retry;
2567	}
2568	if (rc)
2569	goto out;
2570	} else
2571	*if_sid = SECINITSID_NETIF;
2572
2573	out:
2574	rcu_read_unlock();
2575	return rc;
2576	}
2577
2578	static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2579	{
2580	int i, fail = 0;
2581
2582	for (i = 0; i < 4; i++)
2583	if (addr[i] != (input[i] & mask[i])) {
2584	fail = 1;
2585	break;
2586	}
2587
2588	return !fail;
2589	}
2590
2591	/**
2592	* security_node_sid - Obtain the SID for a node (host).
2593	* @domain: communication domain aka address family
2594	* @addrp: address
2595	* @addrlen: address length in bytes
2596	* @out_sid: security identifier
2597	*/
2598	int security_node_sid(u16 domain,
2599	void *addrp,
2600	u32 addrlen,
2601	u32 *out_sid)
2602	{
2603	struct selinux_policy *policy;
2604	struct policydb *policydb;
2605	struct sidtab *sidtab;
2606	int rc;
2607	struct ocontext *c;
2608
2609	if (!selinux_initialized()) {
2610	*out_sid = SECINITSID_NODE;
2611	return 0;
2612	}
2613
2614	retry:
2615	rcu_read_lock();
2616	policy = rcu_dereference(selinux_state.policy);
2617	policydb = &policy->policydb;
2618	sidtab = policy->sidtab;
2619
2620	switch (domain) {
2621	case AF_INET: {
2622	u32 addr;
2623
2624	rc = -EINVAL;
2625	if (addrlen != sizeof(u32))
2626	goto out;
2627
2628	addr = *((u32 *)addrp);
2629
2630	c = policydb->ocontexts[OCON_NODE];
2631	while (c) {
2632	if (c->u.node.addr == (addr & c->u.node.mask))
2633	break;
2634	c = c->next;
2635	}
2636	break;
2637	}
2638
2639	case AF_INET6:
2640	rc = -EINVAL;
2641	if (addrlen != sizeof(u64) * 2)
2642	goto out;
2643	c = policydb->ocontexts[OCON_NODE6];
2644	while (c) {
2645	if (match_ipv6_addrmask(input: addrp, addr: c->u.node6.addr,
2646	mask: c->u.node6.mask))
2647	break;
2648	c = c->next;
2649	}
2650	break;
2651
2652	default:
2653	rc = 0;
2654	*out_sid = SECINITSID_NODE;
2655	goto out;
2656	}
2657
2658	if (c) {
2659	rc = ocontext_to_sid(sidtab, c, index: 0, out_sid);
2660	if (rc == -ESTALE) {
2661	rcu_read_unlock();
2662	goto retry;
2663	}
2664	if (rc)
2665	goto out;
2666	} else {
2667	*out_sid = SECINITSID_NODE;
2668	}
2669
2670	rc = 0;
2671	out:
2672	rcu_read_unlock();
2673	return rc;
2674	}
2675
2676	#define SIDS_NEL 25
2677
2678	/**
2679	* security_get_user_sids - Obtain reachable SIDs for a user.
2680	* @fromsid: starting SID
2681	* @username: username
2682	* @sids: array of reachable SIDs for user
2683	* @nel: number of elements in @sids
2684	*
2685	* Generate the set of SIDs for legal security contexts
2686	* for a given user that can be reached by @fromsid.
2687	* Set *@sids to point to a dynamically allocated
2688	* array containing the set of SIDs. Set *@nel to the
2689	* number of elements in the array.
2690	*/
2691
2692	int security_get_user_sids(u32 fromsid,
2693	char *username,
2694	u32 **sids,
2695	u32 *nel)
2696	{
2697	struct selinux_policy *policy;
2698	struct policydb *policydb;
2699	struct sidtab *sidtab;
2700	struct context *fromcon, usercon;
2701	u32 *mysids = NULL, *mysids2, sid;
2702	u32 i, j, mynel, maxnel = SIDS_NEL;
2703	struct user_datum *user;
2704	struct role_datum *role;
2705	struct ebitmap_node *rnode, *tnode;
2706	int rc;
2707
2708	*sids = NULL;
2709	*nel = 0;
2710
2711	if (!selinux_initialized())
2712	return 0;
2713
2714	mysids = kcalloc(n: maxnel, size: sizeof(*mysids), GFP_KERNEL);
2715	if (!mysids)
2716	return -ENOMEM;
2717
2718	retry:
2719	mynel = 0;
2720	rcu_read_lock();
2721	policy = rcu_dereference(selinux_state.policy);
2722	policydb = &policy->policydb;
2723	sidtab = policy->sidtab;
2724
2725	context_init(c: &usercon);
2726
2727	rc = -EINVAL;
2728	fromcon = sidtab_search(s: sidtab, sid: fromsid);
2729	if (!fromcon)
2730	goto out_unlock;
2731
2732	rc = -EINVAL;
2733	user = symtab_search(s: &policydb->p_users, name: username);
2734	if (!user)
2735	goto out_unlock;
2736
2737	usercon.user = user->value;
2738
2739	ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2740	role = policydb->role_val_to_struct[i];
2741	usercon.role = i + 1;
2742	ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2743	usercon.type = j + 1;
2744
2745	if (mls_setup_user_range(p: policydb, fromcon, user,
2746	usercon: &usercon))
2747	continue;
2748
2749	rc = sidtab_context_to_sid(s: sidtab, context: &usercon, sid: &sid);
2750	if (rc == -ESTALE) {
2751	rcu_read_unlock();
2752	goto retry;
2753	}
2754	if (rc)
2755	goto out_unlock;
2756	if (mynel < maxnel) {
2757	mysids[mynel++] = sid;
2758	} else {
2759	rc = -ENOMEM;
2760	maxnel += SIDS_NEL;
2761	mysids2 = kcalloc(n: maxnel, size: sizeof(*mysids2), GFP_ATOMIC);
2762	if (!mysids2)
2763	goto out_unlock;
2764	memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2765	kfree(objp: mysids);
2766	mysids = mysids2;
2767	mysids[mynel++] = sid;
2768	}
2769	}
2770	}
2771	rc = 0;
2772	out_unlock:
2773	rcu_read_unlock();
2774	if (rc || !mynel) {
2775	kfree(objp: mysids);
2776	return rc;
2777	}
2778
2779	rc = -ENOMEM;
2780	mysids2 = kcalloc(n: mynel, size: sizeof(*mysids2), GFP_KERNEL);
2781	if (!mysids2) {
2782	kfree(objp: mysids);
2783	return rc;
2784	}
2785	for (i = 0, j = 0; i < mynel; i++) {
2786	struct av_decision dummy_avd;
2787	rc = avc_has_perm_noaudit(fromsid, mysids[i],
2788	SECCLASS_PROCESS, /* kernel value */
2789	PROCESS__TRANSITION, AVC_STRICT,
2790	&dummy_avd);
2791	if (!rc)
2792	mysids2[j++] = mysids[i];
2793	cond_resched();
2794	}
2795	kfree(objp: mysids);
2796	*sids = mysids2;
2797	*nel = j;
2798	return 0;
2799	}
2800
2801	/**
2802	* __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2803	* @policy: policy
2804	* @fstype: filesystem type
2805	* @path: path from root of mount
2806	* @orig_sclass: file security class
2807	* @sid: SID for path
2808	*
2809	* Obtain a SID to use for a file in a filesystem that
2810	* cannot support xattr or use a fixed labeling behavior like
2811	* transition SIDs or task SIDs.
2812	*
2813	* WARNING: This function may return -ESTALE, indicating that the caller
2814	* must retry the operation after re-acquiring the policy pointer!
2815	*/
2816	static inline int __security_genfs_sid(struct selinux_policy *policy,
2817	const char *fstype,
2818	const char *path,
2819	u16 orig_sclass,
2820	u32 *sid)
2821	{
2822	struct policydb *policydb = &policy->policydb;
2823	struct sidtab *sidtab = policy->sidtab;
2824	u16 sclass;
2825	struct genfs *genfs;
2826	struct ocontext *c;
2827	int cmp = 0;
2828
2829	while (path[0] == '/' && path[1] == '/')
2830	path++;
2831
2832	sclass = unmap_class(map: &policy->map, tclass: orig_sclass);
2833	*sid = SECINITSID_UNLABELED;
2834
2835	for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2836	cmp = strcmp(fstype, genfs->fstype);
2837	if (cmp <= 0)
2838	break;
2839	}
2840
2841	if (!genfs || cmp)
2842	return -ENOENT;
2843
2844	for (c = genfs->head; c; c = c->next) {
2845	size_t len = strlen(c->u.name);
2846	if ((!c->v.sclass || sclass == c->v.sclass) &&
2847	(strncmp(c->u.name, path, len) == 0))
2848	break;
2849	}
2850
2851	if (!c)
2852	return -ENOENT;
2853
2854	return ocontext_to_sid(sidtab, c, index: 0, out_sid: sid);
2855	}
2856
2857	/**
2858	* security_genfs_sid - Obtain a SID for a file in a filesystem
2859	* @fstype: filesystem type
2860	* @path: path from root of mount
2861	* @orig_sclass: file security class
2862	* @sid: SID for path
2863	*
2864	* Acquire policy_rwlock before calling __security_genfs_sid() and release
2865	* it afterward.
2866	*/
2867	int security_genfs_sid(const char *fstype,
2868	const char *path,
2869	u16 orig_sclass,
2870	u32 *sid)
2871	{
2872	struct selinux_policy *policy;
2873	int retval;
2874
2875	if (!selinux_initialized()) {
2876	*sid = SECINITSID_UNLABELED;
2877	return 0;
2878	}
2879
2880	do {
2881	rcu_read_lock();
2882	policy = rcu_dereference(selinux_state.policy);
2883	retval = __security_genfs_sid(policy, fstype, path,
2884	orig_sclass, sid);
2885	rcu_read_unlock();
2886	} while (retval == -ESTALE);
2887	return retval;
2888	}
2889
2890	int selinux_policy_genfs_sid(struct selinux_policy *policy,
2891	const char *fstype,
2892	const char *path,
2893	u16 orig_sclass,
2894	u32 *sid)
2895	{
2896	/* no lock required, policy is not yet accessible by other threads */
2897	return __security_genfs_sid(policy, fstype, path, orig_sclass, sid);
2898	}
2899
2900	/**
2901	* security_fs_use - Determine how to handle labeling for a filesystem.
2902	* @sb: superblock in question
2903	*/
2904	int security_fs_use(struct super_block *sb)
2905	{
2906	struct selinux_policy *policy;
2907	struct policydb *policydb;
2908	struct sidtab *sidtab;
2909	int rc;
2910	struct ocontext *c;
2911	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2912	const char *fstype = sb->s_type->name;
2913
2914	if (!selinux_initialized()) {
2915	sbsec->behavior = SECURITY_FS_USE_NONE;
2916	sbsec->sid = SECINITSID_UNLABELED;
2917	return 0;
2918	}
2919
2920	retry:
2921	rcu_read_lock();
2922	policy = rcu_dereference(selinux_state.policy);
2923	policydb = &policy->policydb;
2924	sidtab = policy->sidtab;
2925
2926	c = policydb->ocontexts[OCON_FSUSE];
2927	while (c) {
2928	if (strcmp(fstype, c->u.name) == 0)
2929	break;
2930	c = c->next;
2931	}
2932
2933	if (c) {
2934	sbsec->behavior = c->v.behavior;
2935	rc = ocontext_to_sid(sidtab, c, index: 0, out_sid: &sbsec->sid);
2936	if (rc == -ESTALE) {
2937	rcu_read_unlock();
2938	goto retry;
2939	}
2940	if (rc)
2941	goto out;
2942	} else {
2943	rc = __security_genfs_sid(policy, fstype, path: "/",
2944	orig_sclass: SECCLASS_DIR, sid: &sbsec->sid);
2945	if (rc == -ESTALE) {
2946	rcu_read_unlock();
2947	goto retry;
2948	}
2949	if (rc) {
2950	sbsec->behavior = SECURITY_FS_USE_NONE;
2951	rc = 0;
2952	} else {
2953	sbsec->behavior = SECURITY_FS_USE_GENFS;
2954	}
2955	}
2956
2957	out:
2958	rcu_read_unlock();
2959	return rc;
2960	}
2961
2962	int security_get_bools(struct selinux_policy *policy,
2963	u32 *len, char ***names, int **values)
2964	{
2965	struct policydb *policydb;
2966	u32 i;
2967	int rc;
2968
2969	policydb = &policy->policydb;
2970
2971	*names = NULL;
2972	*values = NULL;
2973
2974	rc = 0;
2975	*len = policydb->p_bools.nprim;
2976	if (!*len)
2977	goto out;
2978
2979	rc = -ENOMEM;
2980	*names = kcalloc(n: *len, size: sizeof(char *), GFP_ATOMIC);
2981	if (!*names)
2982	goto err;
2983
2984	rc = -ENOMEM;
2985	*values = kcalloc(n: *len, size: sizeof(int), GFP_ATOMIC);
2986	if (!*values)
2987	goto err;
2988
2989	for (i = 0; i < *len; i++) {
2990	(*values)[i] = policydb->bool_val_to_struct[i]->state;
2991
2992	rc = -ENOMEM;
2993	(*names)[i] = kstrdup(s: sym_name(p: policydb, SYM_BOOLS, element_nr: i),
2994	GFP_ATOMIC);
2995	if (!(*names)[i])
2996	goto err;
2997	}
2998	rc = 0;
2999	out:
3000	return rc;
3001	err:
3002	if (*names) {
3003	for (i = 0; i < *len; i++)
3004	kfree(objp: (*names)[i]);
3005	kfree(objp: *names);
3006	}
3007	kfree(objp: *values);
3008	*len = 0;
3009	*names = NULL;
3010	*values = NULL;
3011	goto out;
3012	}
3013
3014
3015	int security_set_bools(u32 len, int *values)
3016	{
3017	struct selinux_state *state = &selinux_state;
3018	struct selinux_policy *newpolicy, *oldpolicy;
3019	int rc;
3020	u32 i, seqno = 0;
3021
3022	if (!selinux_initialized())
3023	return -EINVAL;
3024
3025	oldpolicy = rcu_dereference_protected(state->policy,
3026	lockdep_is_held(&state->policy_mutex));
3027
3028	/* Consistency check on number of booleans, should never fail */
3029	if (WARN_ON(len != oldpolicy->policydb.p_bools.nprim))
3030	return -EINVAL;
3031
3032	newpolicy = kmemdup(p: oldpolicy, size: sizeof(*newpolicy), GFP_KERNEL);
3033	if (!newpolicy)
3034	return -ENOMEM;
3035
3036	/*
3037	* Deep copy only the parts of the policydb that might be
3038	* modified as a result of changing booleans.
3039	*/
3040	rc = cond_policydb_dup(new: &newpolicy->policydb, orig: &oldpolicy->policydb);
3041	if (rc) {
3042	kfree(objp: newpolicy);
3043	return -ENOMEM;
3044	}
3045
3046	/* Update the boolean states in the copy */
3047	for (i = 0; i < len; i++) {
3048	int new_state = !!values[i];
3049	int old_state = newpolicy->policydb.bool_val_to_struct[i]->state;
3050
3051	if (new_state != old_state) {
3052	audit_log(ctx: audit_context(), GFP_ATOMIC,
3053	AUDIT_MAC_CONFIG_CHANGE,
3054	fmt: "bool=%s val=%d old_val=%d auid=%u ses=%u",
3055	sym_name(p: &newpolicy->policydb, SYM_BOOLS, element_nr: i),
3056	new_state,
3057	old_state,
3058	from_kuid(to: &init_user_ns, uid: audit_get_loginuid(current)),
3059	audit_get_sessionid(current));
3060	newpolicy->policydb.bool_val_to_struct[i]->state = new_state;
3061	}
3062	}
3063
3064	/* Re-evaluate the conditional rules in the copy */
3065	evaluate_cond_nodes(p: &newpolicy->policydb);
3066
3067	/* Set latest granting seqno for new policy */
3068	newpolicy->latest_granting = oldpolicy->latest_granting + 1;
3069	seqno = newpolicy->latest_granting;
3070
3071	/* Install the new policy */
3072	rcu_assign_pointer(state->policy, newpolicy);
3073
3074	/*
3075	* Free the conditional portions of the old policydb
3076	* that were copied for the new policy, and the oldpolicy
3077	* structure itself but not what it references.
3078	*/
3079	synchronize_rcu();
3080	selinux_policy_cond_free(policy: oldpolicy);
3081
3082	/* Notify others of the policy change */
3083	selinux_notify_policy_change(seqno);
3084	return 0;
3085	}
3086
3087	int security_get_bool_value(u32 index)
3088	{
3089	struct selinux_policy *policy;
3090	struct policydb *policydb;
3091	int rc;
3092	u32 len;
3093
3094	if (!selinux_initialized())
3095	return 0;
3096
3097	rcu_read_lock();
3098	policy = rcu_dereference(selinux_state.policy);
3099	policydb = &policy->policydb;
3100
3101	rc = -EFAULT;
3102	len = policydb->p_bools.nprim;
3103	if (index >= len)
3104	goto out;
3105
3106	rc = policydb->bool_val_to_struct[index]->state;
3107	out:
3108	rcu_read_unlock();
3109	return rc;
3110	}
3111
3112	static int security_preserve_bools(struct selinux_policy *oldpolicy,
3113	struct selinux_policy *newpolicy)
3114	{
3115	int rc, *bvalues = NULL;
3116	char **bnames = NULL;
3117	struct cond_bool_datum *booldatum;
3118	u32 i, nbools = 0;
3119
3120	rc = security_get_bools(policy: oldpolicy, len: &nbools, names: &bnames, values: &bvalues);
3121	if (rc)
3122	goto out;
3123	for (i = 0; i < nbools; i++) {
3124	booldatum = symtab_search(s: &newpolicy->policydb.p_bools,
3125	name: bnames[i]);
3126	if (booldatum)
3127	booldatum->state = bvalues[i];
3128	}
3129	evaluate_cond_nodes(p: &newpolicy->policydb);
3130
3131	out:
3132	if (bnames) {
3133	for (i = 0; i < nbools; i++)
3134	kfree(objp: bnames[i]);
3135	}
3136	kfree(objp: bnames);
3137	kfree(objp: bvalues);
3138	return rc;
3139	}
3140
3141	/*
3142	* security_sid_mls_copy() - computes a new sid based on the given
3143	* sid and the mls portion of mls_sid.
3144	*/
3145	int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
3146	{
3147	struct selinux_policy *policy;
3148	struct policydb *policydb;
3149	struct sidtab *sidtab;
3150	struct context *context1;
3151	struct context *context2;
3152	struct context newcon;
3153	char *s;
3154	u32 len;
3155	int rc;
3156
3157	if (!selinux_initialized()) {
3158	*new_sid = sid;
3159	return 0;
3160	}
3161
3162	retry:
3163	rc = 0;
3164	context_init(c: &newcon);
3165
3166	rcu_read_lock();
3167	policy = rcu_dereference(selinux_state.policy);
3168	policydb = &policy->policydb;
3169	sidtab = policy->sidtab;
3170
3171	if (!policydb->mls_enabled) {
3172	*new_sid = sid;
3173	goto out_unlock;
3174	}
3175
3176	rc = -EINVAL;
3177	context1 = sidtab_search(s: sidtab, sid);
3178	if (!context1) {
3179	pr_err("SELinux: %s: unrecognized SID %d\n",
3180	__func__, sid);
3181	goto out_unlock;
3182	}
3183
3184	rc = -EINVAL;
3185	context2 = sidtab_search(s: sidtab, sid: mls_sid);
3186	if (!context2) {
3187	pr_err("SELinux: %s: unrecognized SID %d\n",
3188	__func__, mls_sid);
3189	goto out_unlock;
3190	}
3191
3192	newcon.user = context1->user;
3193	newcon.role = context1->role;
3194	newcon.type = context1->type;
3195	rc = mls_context_cpy(dst: &newcon, src: context2);
3196	if (rc)
3197	goto out_unlock;
3198
3199	/* Check the validity of the new context. */
3200	if (!policydb_context_isvalid(p: policydb, c: &newcon)) {
3201	rc = convert_context_handle_invalid_context(policydb,
3202	context: &newcon);
3203	if (rc) {
3204	if (!context_struct_to_string(p: policydb, context: &newcon, scontext: &s,
3205	scontext_len: &len)) {
3206	struct audit_buffer *ab;
3207
3208	ab = audit_log_start(ctx: audit_context(),
3209	GFP_ATOMIC,
3210	AUDIT_SELINUX_ERR);
3211	audit_log_format(ab,
3212	fmt: "op=security_sid_mls_copy invalid_context=");
3213	/* don't record NUL with untrusted strings */
3214	audit_log_n_untrustedstring(ab, string: s, n: len - 1);
3215	audit_log_end(ab);
3216	kfree(objp: s);
3217	}
3218	goto out_unlock;
3219	}
3220	}
3221	rc = sidtab_context_to_sid(s: sidtab, context: &newcon, sid: new_sid);
3222	if (rc == -ESTALE) {
3223	rcu_read_unlock();
3224	context_destroy(c: &newcon);
3225	goto retry;
3226	}
3227	out_unlock:
3228	rcu_read_unlock();
3229	context_destroy(c: &newcon);
3230	return rc;
3231	}
3232
3233	/**
3234	* security_net_peersid_resolve - Compare and resolve two network peer SIDs
3235	* @nlbl_sid: NetLabel SID
3236	* @nlbl_type: NetLabel labeling protocol type
3237	* @xfrm_sid: XFRM SID
3238	* @peer_sid: network peer sid
3239	*
3240	* Description:
3241	* Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3242	* resolved into a single SID it is returned via @peer_sid and the function
3243	* returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3244	* returns a negative value. A table summarizing the behavior is below:
3245	*
3246	* | function return | @sid
3247	* ------------------------------+-----------------+-----------------
3248	* no peer labels | 0 | SECSID_NULL
3249	* single peer label | 0 | <peer_label>
3250	* multiple, consistent labels | 0 | <peer_label>
3251	* multiple, inconsistent labels | -<errno> | SECSID_NULL
3252	*
3253	*/
3254	int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
3255	u32 xfrm_sid,
3256	u32 *peer_sid)
3257	{
3258	struct selinux_policy *policy;
3259	struct policydb *policydb;
3260	struct sidtab *sidtab;
3261	int rc;
3262	struct context *nlbl_ctx;
3263	struct context *xfrm_ctx;
3264
3265	*peer_sid = SECSID_NULL;
3266
3267	/* handle the common (which also happens to be the set of easy) cases
3268	* right away, these two if statements catch everything involving a
3269	* single or absent peer SID/label */
3270	if (xfrm_sid == SECSID_NULL) {
3271	*peer_sid = nlbl_sid;
3272	return 0;
3273	}
3274	/* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3275	* and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3276	* is present */
3277	if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3278	*peer_sid = xfrm_sid;
3279	return 0;
3280	}
3281
3282	if (!selinux_initialized())
3283	return 0;
3284
3285	rcu_read_lock();
3286	policy = rcu_dereference(selinux_state.policy);
3287	policydb = &policy->policydb;
3288	sidtab = policy->sidtab;
3289
3290	/*
3291	* We don't need to check initialized here since the only way both
3292	* nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3293	* security server was initialized and state->initialized was true.
3294	*/
3295	if (!policydb->mls_enabled) {
3296	rc = 0;
3297	goto out;
3298	}
3299
3300	rc = -EINVAL;
3301	nlbl_ctx = sidtab_search(s: sidtab, sid: nlbl_sid);
3302	if (!nlbl_ctx) {
3303	pr_err("SELinux: %s: unrecognized SID %d\n",
3304	__func__, nlbl_sid);
3305	goto out;
3306	}
3307	rc = -EINVAL;
3308	xfrm_ctx = sidtab_search(s: sidtab, sid: xfrm_sid);
3309	if (!xfrm_ctx) {
3310	pr_err("SELinux: %s: unrecognized SID %d\n",
3311	__func__, xfrm_sid);
3312	goto out;
3313	}
3314	rc = (mls_context_cmp(c1: nlbl_ctx, c2: xfrm_ctx) ? 0 : -EACCES);
3315	if (rc)
3316	goto out;
3317
3318	/* at present NetLabel SIDs/labels really only carry MLS
3319	* information so if the MLS portion of the NetLabel SID
3320	* matches the MLS portion of the labeled XFRM SID/label
3321	* then pass along the XFRM SID as it is the most
3322	* expressive */
3323	*peer_sid = xfrm_sid;
3324	out:
3325	rcu_read_unlock();
3326	return rc;
3327	}
3328
3329	static int get_classes_callback(void *k, void *d, void *args)
3330	{
3331	struct class_datum *datum = d;
3332	char *name = k, **classes = args;
3333	u32 value = datum->value - 1;
3334
3335	classes[value] = kstrdup(s: name, GFP_ATOMIC);
3336	if (!classes[value])
3337	return -ENOMEM;
3338
3339	return 0;
3340	}
3341
3342	int security_get_classes(struct selinux_policy *policy,
3343	char ***classes, u32 *nclasses)
3344	{
3345	struct policydb *policydb;
3346	int rc;
3347
3348	policydb = &policy->policydb;
3349
3350	rc = -ENOMEM;
3351	*nclasses = policydb->p_classes.nprim;
3352	*classes = kcalloc(n: *nclasses, size: sizeof(**classes), GFP_ATOMIC);
3353	if (!*classes)
3354	goto out;
3355
3356	rc = hashtab_map(h: &policydb->p_classes.table, apply: get_classes_callback,
3357	args: *classes);
3358	if (rc) {
3359	u32 i;
3360
3361	for (i = 0; i < *nclasses; i++)
3362	kfree(objp: (*classes)[i]);
3363	kfree(objp: *classes);
3364	}
3365
3366	out:
3367	return rc;
3368	}
3369
3370	static int get_permissions_callback(void *k, void *d, void *args)
3371	{
3372	struct perm_datum *datum = d;
3373	char *name = k, **perms = args;
3374	u32 value = datum->value - 1;
3375
3376	perms[value] = kstrdup(s: name, GFP_ATOMIC);
3377	if (!perms[value])
3378	return -ENOMEM;
3379
3380	return 0;
3381	}
3382
3383	int security_get_permissions(struct selinux_policy *policy,
3384	const char *class, char ***perms, u32 *nperms)
3385	{
3386	struct policydb *policydb;
3387	u32 i;
3388	int rc;
3389	struct class_datum *match;
3390
3391	policydb = &policy->policydb;
3392
3393	rc = -EINVAL;
3394	match = symtab_search(s: &policydb->p_classes, name: class);
3395	if (!match) {
3396	pr_err("SELinux: %s: unrecognized class %s\n",
3397	__func__, class);
3398	goto out;
3399	}
3400
3401	rc = -ENOMEM;
3402	*nperms = match->permissions.nprim;
3403	*perms = kcalloc(n: *nperms, size: sizeof(**perms), GFP_ATOMIC);
3404	if (!*perms)
3405	goto out;
3406
3407	if (match->comdatum) {
3408	rc = hashtab_map(h: &match->comdatum->permissions.table,
3409	apply: get_permissions_callback, args: *perms);
3410	if (rc)
3411	goto err;
3412	}
3413
3414	rc = hashtab_map(h: &match->permissions.table, apply: get_permissions_callback,
3415	args: *perms);
3416	if (rc)
3417	goto err;
3418
3419	out:
3420	return rc;
3421
3422	err:
3423	for (i = 0; i < *nperms; i++)
3424	kfree(objp: (*perms)[i]);
3425	kfree(objp: *perms);
3426	return rc;
3427	}
3428
3429	int security_get_reject_unknown(void)
3430	{
3431	struct selinux_policy *policy;
3432	int value;
3433
3434	if (!selinux_initialized())
3435	return 0;
3436
3437	rcu_read_lock();
3438	policy = rcu_dereference(selinux_state.policy);
3439	value = policy->policydb.reject_unknown;
3440	rcu_read_unlock();
3441	return value;
3442	}
3443
3444	int security_get_allow_unknown(void)
3445	{
3446	struct selinux_policy *policy;
3447	int value;
3448
3449	if (!selinux_initialized())
3450	return 0;
3451
3452	rcu_read_lock();
3453	policy = rcu_dereference(selinux_state.policy);
3454	value = policy->policydb.allow_unknown;
3455	rcu_read_unlock();
3456	return value;
3457	}
3458
3459	/**
3460	* security_policycap_supported - Check for a specific policy capability
3461	* @req_cap: capability
3462	*
3463	* Description:
3464	* This function queries the currently loaded policy to see if it supports the
3465	* capability specified by @req_cap. Returns true (1) if the capability is
3466	* supported, false (0) if it isn't supported.
3467	*
3468	*/
3469	int security_policycap_supported(unsigned int req_cap)
3470	{
3471	struct selinux_policy *policy;
3472	int rc;
3473
3474	if (!selinux_initialized())
3475	return 0;
3476
3477	rcu_read_lock();
3478	policy = rcu_dereference(selinux_state.policy);
3479	rc = ebitmap_get_bit(e: &policy->policydb.policycaps, bit: req_cap);
3480	rcu_read_unlock();
3481
3482	return rc;
3483	}
3484
3485	struct selinux_audit_rule {
3486	u32 au_seqno;
3487	struct context au_ctxt;
3488	};
3489
3490	void selinux_audit_rule_free(void *vrule)
3491	{
3492	struct selinux_audit_rule *rule = vrule;
3493
3494	if (rule) {
3495	context_destroy(c: &rule->au_ctxt);
3496	kfree(objp: rule);
3497	}
3498	}
3499
3500	int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3501	{
3502	struct selinux_state *state = &selinux_state;
3503	struct selinux_policy *policy;
3504	struct policydb *policydb;
3505	struct selinux_audit_rule *tmprule;
3506	struct role_datum *roledatum;
3507	struct type_datum *typedatum;
3508	struct user_datum *userdatum;
3509	struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3510	int rc = 0;
3511
3512	*rule = NULL;
3513
3514	if (!selinux_initialized())
3515	return -EOPNOTSUPP;
3516
3517	switch (field) {
3518	case AUDIT_SUBJ_USER:
3519	case AUDIT_SUBJ_ROLE:
3520	case AUDIT_SUBJ_TYPE:
3521	case AUDIT_OBJ_USER:
3522	case AUDIT_OBJ_ROLE:
3523	case AUDIT_OBJ_TYPE:
3524	/* only 'equals' and 'not equals' fit user, role, and type */
3525	if (op != Audit_equal && op != Audit_not_equal)
3526	return -EINVAL;
3527	break;
3528	case AUDIT_SUBJ_SEN:
3529	case AUDIT_SUBJ_CLR:
3530	case AUDIT_OBJ_LEV_LOW:
3531	case AUDIT_OBJ_LEV_HIGH:
3532	/* we do not allow a range, indicated by the presence of '-' */
3533	if (strchr(rulestr, '-'))
3534	return -EINVAL;
3535	break;
3536	default:
3537	/* only the above fields are valid */
3538	return -EINVAL;
3539	}
3540
3541	tmprule = kzalloc(size: sizeof(struct selinux_audit_rule), GFP_KERNEL);
3542	if (!tmprule)
3543	return -ENOMEM;
3544	context_init(c: &tmprule->au_ctxt);
3545
3546	rcu_read_lock();
3547	policy = rcu_dereference(state->policy);
3548	policydb = &policy->policydb;
3549	tmprule->au_seqno = policy->latest_granting;
3550	switch (field) {
3551	case AUDIT_SUBJ_USER:
3552	case AUDIT_OBJ_USER:
3553	userdatum = symtab_search(s: &policydb->p_users, name: rulestr);
3554	if (!userdatum) {
3555	rc = -EINVAL;
3556	goto err;
3557	}
3558	tmprule->au_ctxt.user = userdatum->value;
3559	break;
3560	case AUDIT_SUBJ_ROLE:
3561	case AUDIT_OBJ_ROLE:
3562	roledatum = symtab_search(s: &policydb->p_roles, name: rulestr);
3563	if (!roledatum) {
3564	rc = -EINVAL;
3565	goto err;
3566	}
3567	tmprule->au_ctxt.role = roledatum->value;
3568	break;
3569	case AUDIT_SUBJ_TYPE:
3570	case AUDIT_OBJ_TYPE:
3571	typedatum = symtab_search(s: &policydb->p_types, name: rulestr);
3572	if (!typedatum) {
3573	rc = -EINVAL;
3574	goto err;
3575	}
3576	tmprule->au_ctxt.type = typedatum->value;
3577	break;
3578	case AUDIT_SUBJ_SEN:
3579	case AUDIT_SUBJ_CLR:
3580	case AUDIT_OBJ_LEV_LOW:
3581	case AUDIT_OBJ_LEV_HIGH:
3582	rc = mls_from_string(p: policydb, str: rulestr, context: &tmprule->au_ctxt,
3583	GFP_ATOMIC);
3584	if (rc)
3585	goto err;
3586	break;
3587	}
3588	rcu_read_unlock();
3589
3590	*rule = tmprule;
3591	return 0;
3592
3593	err:
3594	rcu_read_unlock();
3595	selinux_audit_rule_free(vrule: tmprule);
3596	*rule = NULL;
3597	return rc;
3598	}
3599
3600	/* Check to see if the rule contains any selinux fields */
3601	int selinux_audit_rule_known(struct audit_krule *rule)
3602	{
3603	u32 i;
3604
3605	for (i = 0; i < rule->field_count; i++) {
3606	struct audit_field *f = &rule->fields[i];
3607	switch (f->type) {
3608	case AUDIT_SUBJ_USER:
3609	case AUDIT_SUBJ_ROLE:
3610	case AUDIT_SUBJ_TYPE:
3611	case AUDIT_SUBJ_SEN:
3612	case AUDIT_SUBJ_CLR:
3613	case AUDIT_OBJ_USER:
3614	case AUDIT_OBJ_ROLE:
3615	case AUDIT_OBJ_TYPE:
3616	case AUDIT_OBJ_LEV_LOW:
3617	case AUDIT_OBJ_LEV_HIGH:
3618	return 1;
3619	}
3620	}
3621
3622	return 0;
3623	}
3624
3625	int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule)
3626	{
3627	struct selinux_state *state = &selinux_state;
3628	struct selinux_policy *policy;
3629	struct context *ctxt;
3630	struct mls_level *level;
3631	struct selinux_audit_rule *rule = vrule;
3632	int match = 0;
3633
3634	if (unlikely(!rule)) {
3635	WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3636	return -ENOENT;
3637	}
3638
3639	if (!selinux_initialized())
3640	return 0;
3641
3642	rcu_read_lock();
3643
3644	policy = rcu_dereference(state->policy);
3645
3646	if (rule->au_seqno < policy->latest_granting) {
3647	match = -ESTALE;
3648	goto out;
3649	}
3650
3651	ctxt = sidtab_search(s: policy->sidtab, sid);
3652	if (unlikely(!ctxt)) {
3653	WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3654	sid);
3655	match = -ENOENT;
3656	goto out;
3657	}
3658
3659	/* a field/op pair that is not caught here will simply fall through
3660	without a match */
3661	switch (field) {
3662	case AUDIT_SUBJ_USER:
3663	case AUDIT_OBJ_USER:
3664	switch (op) {
3665	case Audit_equal:
3666	match = (ctxt->user == rule->au_ctxt.user);
3667	break;
3668	case Audit_not_equal:
3669	match = (ctxt->user != rule->au_ctxt.user);
3670	break;
3671	}
3672	break;
3673	case AUDIT_SUBJ_ROLE:
3674	case AUDIT_OBJ_ROLE:
3675	switch (op) {
3676	case Audit_equal:
3677	match = (ctxt->role == rule->au_ctxt.role);
3678	break;
3679	case Audit_not_equal:
3680	match = (ctxt->role != rule->au_ctxt.role);
3681	break;
3682	}
3683	break;
3684	case AUDIT_SUBJ_TYPE:
3685	case AUDIT_OBJ_TYPE:
3686	switch (op) {
3687	case Audit_equal:
3688	match = (ctxt->type == rule->au_ctxt.type);
3689	break;
3690	case Audit_not_equal:
3691	match = (ctxt->type != rule->au_ctxt.type);
3692	break;
3693	}
3694	break;
3695	case AUDIT_SUBJ_SEN:
3696	case AUDIT_SUBJ_CLR:
3697	case AUDIT_OBJ_LEV_LOW:
3698	case AUDIT_OBJ_LEV_HIGH:
3699	level = ((field == AUDIT_SUBJ_SEN ||
3700	field == AUDIT_OBJ_LEV_LOW) ?
3701	&ctxt->range.level[0] : &ctxt->range.level[1]);
3702	switch (op) {
3703	case Audit_equal:
3704	match = mls_level_eq(l1: &rule->au_ctxt.range.level[0],
3705	l2: level);
3706	break;
3707	case Audit_not_equal:
3708	match = !mls_level_eq(l1: &rule->au_ctxt.range.level[0],
3709	l2: level);
3710	break;
3711	case Audit_lt:
3712	match = (mls_level_dom(l1: &rule->au_ctxt.range.level[0],
3713	l2: level) &&
3714	!mls_level_eq(l1: &rule->au_ctxt.range.level[0],
3715	l2: level));
3716	break;
3717	case Audit_le:
3718	match = mls_level_dom(l1: &rule->au_ctxt.range.level[0],
3719	l2: level);
3720	break;
3721	case Audit_gt:
3722	match = (mls_level_dom(l1: level,
3723	l2: &rule->au_ctxt.range.level[0]) &&
3724	!mls_level_eq(l1: level,
3725	l2: &rule->au_ctxt.range.level[0]));
3726	break;
3727	case Audit_ge:
3728	match = mls_level_dom(l1: level,
3729	l2: &rule->au_ctxt.range.level[0]);
3730	break;
3731	}
3732	}
3733
3734	out:
3735	rcu_read_unlock();
3736	return match;
3737	}
3738
3739	static int aurule_avc_callback(u32 event)
3740	{
3741	if (event == AVC_CALLBACK_RESET)
3742	return audit_update_lsm_rules();
3743	return 0;
3744	}
3745
3746	static int __init aurule_init(void)
3747	{
3748	int err;
3749
3750	err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3751	if (err)
3752	panic(fmt: "avc_add_callback() failed, error %d\n", err);
3753
3754	return err;
3755	}
3756	__initcall(aurule_init);
3757
3758	#ifdef CONFIG_NETLABEL
3759	/**
3760	* security_netlbl_cache_add - Add an entry to the NetLabel cache
3761	* @secattr: the NetLabel packet security attributes
3762	* @sid: the SELinux SID
3763	*
3764	* Description:
3765	* Attempt to cache the context in @ctx, which was derived from the packet in
3766	* @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3767	* already been initialized.
3768	*
3769	*/
3770	static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3771	u32 sid)
3772	{
3773	u32 *sid_cache;
3774
3775	sid_cache = kmalloc(size: sizeof(*sid_cache), GFP_ATOMIC);
3776	if (sid_cache == NULL)
3777	return;
3778	secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3779	if (secattr->cache == NULL) {
3780	kfree(objp: sid_cache);
3781	return;
3782	}
3783
3784	*sid_cache = sid;
3785	secattr->cache->free = kfree;
3786	secattr->cache->data = sid_cache;
3787	secattr->flags |= NETLBL_SECATTR_CACHE;
3788	}
3789
3790	/**
3791	* security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3792	* @secattr: the NetLabel packet security attributes
3793	* @sid: the SELinux SID
3794	*
3795	* Description:
3796	* Convert the given NetLabel security attributes in @secattr into a
3797	* SELinux SID. If the @secattr field does not contain a full SELinux
3798	* SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3799	* 'cache' field of @secattr is set and the CACHE flag is set; this is to
3800	* allow the @secattr to be used by NetLabel to cache the secattr to SID
3801	* conversion for future lookups. Returns zero on success, negative values on
3802	* failure.
3803	*
3804	*/
3805	int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3806	u32 *sid)
3807	{
3808	struct selinux_policy *policy;
3809	struct policydb *policydb;
3810	struct sidtab *sidtab;
3811	int rc;
3812	struct context *ctx;
3813	struct context ctx_new;
3814
3815	if (!selinux_initialized()) {
3816	*sid = SECSID_NULL;
3817	return 0;
3818	}
3819
3820	retry:
3821	rc = 0;
3822	rcu_read_lock();
3823	policy = rcu_dereference(selinux_state.policy);
3824	policydb = &policy->policydb;
3825	sidtab = policy->sidtab;
3826
3827	if (secattr->flags & NETLBL_SECATTR_CACHE)
3828	*sid = *(u32 *)secattr->cache->data;
3829	else if (secattr->flags & NETLBL_SECATTR_SECID)
3830	*sid = secattr->attr.secid;
3831	else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3832	rc = -EIDRM;
3833	ctx = sidtab_search(s: sidtab, sid: SECINITSID_NETMSG);
3834	if (ctx == NULL)
3835	goto out;
3836
3837	context_init(c: &ctx_new);
3838	ctx_new.user = ctx->user;
3839	ctx_new.role = ctx->role;
3840	ctx_new.type = ctx->type;
3841	mls_import_netlbl_lvl(p: policydb, context: &ctx_new, secattr);
3842	if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3843	rc = mls_import_netlbl_cat(p: policydb, context: &ctx_new, secattr);
3844	if (rc)
3845	goto out;
3846	}
3847	rc = -EIDRM;
3848	if (!mls_context_isvalid(p: policydb, c: &ctx_new)) {
3849	ebitmap_destroy(e: &ctx_new.range.level[0].cat);
3850	goto out;
3851	}
3852
3853	rc = sidtab_context_to_sid(s: sidtab, context: &ctx_new, sid);
3854	ebitmap_destroy(e: &ctx_new.range.level[0].cat);
3855	if (rc == -ESTALE) {
3856	rcu_read_unlock();
3857	goto retry;
3858	}
3859	if (rc)
3860	goto out;
3861
3862	security_netlbl_cache_add(secattr, sid: *sid);
3863	} else
3864	*sid = SECSID_NULL;
3865
3866	out:
3867	rcu_read_unlock();
3868	return rc;
3869	}
3870
3871	/**
3872	* security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3873	* @sid: the SELinux SID
3874	* @secattr: the NetLabel packet security attributes
3875	*
3876	* Description:
3877	* Convert the given SELinux SID in @sid into a NetLabel security attribute.
3878	* Returns zero on success, negative values on failure.
3879	*
3880	*/
3881	int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3882	{
3883	struct selinux_policy *policy;
3884	struct policydb *policydb;
3885	int rc;
3886	struct context *ctx;
3887
3888	if (!selinux_initialized())
3889	return 0;
3890
3891	rcu_read_lock();
3892	policy = rcu_dereference(selinux_state.policy);
3893	policydb = &policy->policydb;
3894
3895	rc = -ENOENT;
3896	ctx = sidtab_search(s: policy->sidtab, sid);
3897	if (ctx == NULL)
3898	goto out;
3899
3900	rc = -ENOMEM;
3901	secattr->domain = kstrdup(s: sym_name(p: policydb, SYM_TYPES, element_nr: ctx->type - 1),
3902	GFP_ATOMIC);
3903	if (secattr->domain == NULL)
3904	goto out;
3905
3906	secattr->attr.secid = sid;
3907	secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3908	mls_export_netlbl_lvl(p: policydb, context: ctx, secattr);
3909	rc = mls_export_netlbl_cat(p: policydb, context: ctx, secattr);
3910	out:
3911	rcu_read_unlock();
3912	return rc;
3913	}
3914	#endif /* CONFIG_NETLABEL */
3915
3916	/**
3917	* __security_read_policy - read the policy.
3918	* @policy: SELinux policy
3919	* @data: binary policy data
3920	* @len: length of data in bytes
3921	*
3922	*/
3923	static int __security_read_policy(struct selinux_policy *policy,
3924	void *data, size_t *len)
3925	{
3926	int rc;
3927	struct policy_file fp;
3928
3929	fp.data = data;
3930	fp.len = *len;
3931
3932	rc = policydb_write(p: &policy->policydb, fp: &fp);
3933	if (rc)
3934	return rc;
3935
3936	*len = (unsigned long)fp.data - (unsigned long)data;
3937	return 0;
3938	}
3939
3940	/**
3941	* security_read_policy - read the policy.
3942	* @data: binary policy data
3943	* @len: length of data in bytes
3944	*
3945	*/
3946	int security_read_policy(void **data, size_t *len)
3947	{
3948	struct selinux_state *state = &selinux_state;
3949	struct selinux_policy *policy;
3950
3951	policy = rcu_dereference_protected(
3952	state->policy, lockdep_is_held(&state->policy_mutex));
3953	if (!policy)
3954	return -EINVAL;
3955
3956	*len = policy->policydb.len;
3957	*data = vmalloc_user(size: *len);
3958	if (!*data)
3959	return -ENOMEM;
3960
3961	return __security_read_policy(policy, data: *data, len);
3962	}
3963
3964	/**
3965	* security_read_state_kernel - read the policy.
3966	* @data: binary policy data
3967	* @len: length of data in bytes
3968	*
3969	* Allocates kernel memory for reading SELinux policy.
3970	* This function is for internal use only and should not
3971	* be used for returning data to user space.
3972	*
3973	* This function must be called with policy_mutex held.
3974	*/
3975	int security_read_state_kernel(void **data, size_t *len)
3976	{
3977	int err;
3978	struct selinux_state *state = &selinux_state;
3979	struct selinux_policy *policy;
3980
3981	policy = rcu_dereference_protected(
3982	state->policy, lockdep_is_held(&state->policy_mutex));
3983	if (!policy)
3984	return -EINVAL;
3985
3986	*len = policy->policydb.len;
3987	*data = vmalloc(size: *len);
3988	if (!*data)
3989	return -ENOMEM;
3990
3991	err = __security_read_policy(policy, data: *data, len);
3992	if (err) {
3993	vfree(addr: *data);
3994	*data = NULL;
3995	*len = 0;
3996	}
3997	return err;
3998	}
3999