Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Implementation of the security services.
4 *
5 * Authors : Stephen Smalley, <sds@tycho.nsa.gov>
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 <net/netlabel.h>
51
52#include "flask.h"
53#include "avc.h"
54#include "avc_ss.h"
55#include "security.h"
56#include "context.h"
57#include "policydb.h"
58#include "sidtab.h"
59#include "services.h"
60#include "conditional.h"
61#include "mls.h"
62#include "objsec.h"
63#include "netlabel.h"
64#include "xfrm.h"
65#include "ebitmap.h"
66#include "audit.h"
67
68/* Policy capability names */
69const char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = {
70 "network_peer_controls",
71 "open_perms",
72 "extended_socket_class",
73 "always_check_network",
74 "cgroup_seclabel",
75 "nnp_nosuid_transition",
76 "genfs_seclabel_symlinks"
77};
78
79static struct selinux_ss selinux_ss;
80
81void selinux_ss_init(struct selinux_ss **ss)
82{
83 rwlock_init(&selinux_ss.policy_rwlock);
84 *ss = &selinux_ss;
85}
86
87/* Forward declaration. */
88static int context_struct_to_string(struct policydb *policydb,
89 struct context *context,
90 char **scontext,
91 u32 *scontext_len);
92
93static int sidtab_entry_to_string(struct policydb *policydb,
94 struct sidtab *sidtab,
95 struct sidtab_entry *entry,
96 char **scontext,
97 u32 *scontext_len);
98
99static void context_struct_compute_av(struct policydb *policydb,
100 struct context *scontext,
101 struct context *tcontext,
102 u16 tclass,
103 struct av_decision *avd,
104 struct extended_perms *xperms);
105
106static int selinux_set_mapping(struct policydb *pol,
107 struct security_class_mapping *map,
108 struct selinux_map *out_map)
109{
110 u16 i, j;
111 unsigned k;
112 bool print_unknown_handle = false;
113
114 /* Find number of classes in the input mapping */
115 if (!map)
116 return -EINVAL;
117 i = 0;
118 while (map[i].name)
119 i++;
120
121 /* Allocate space for the class records, plus one for class zero */
122 out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC);
123 if (!out_map->mapping)
124 return -ENOMEM;
125
126 /* Store the raw class and permission values */
127 j = 0;
128 while (map[j].name) {
129 struct security_class_mapping *p_in = map + (j++);
130 struct selinux_mapping *p_out = out_map->mapping + j;
131
132 /* An empty class string skips ahead */
133 if (!strcmp(p_in->name, "")) {
134 p_out->num_perms = 0;
135 continue;
136 }
137
138 p_out->value = string_to_security_class(pol, p_in->name);
139 if (!p_out->value) {
140 pr_info("SELinux: Class %s not defined in policy.\n",
141 p_in->name);
142 if (pol->reject_unknown)
143 goto err;
144 p_out->num_perms = 0;
145 print_unknown_handle = true;
146 continue;
147 }
148
149 k = 0;
150 while (p_in->perms[k]) {
151 /* An empty permission string skips ahead */
152 if (!*p_in->perms[k]) {
153 k++;
154 continue;
155 }
156 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
157 p_in->perms[k]);
158 if (!p_out->perms[k]) {
159 pr_info("SELinux: Permission %s in class %s not defined in policy.\n",
160 p_in->perms[k], p_in->name);
161 if (pol->reject_unknown)
162 goto err;
163 print_unknown_handle = true;
164 }
165
166 k++;
167 }
168 p_out->num_perms = k;
169 }
170
171 if (print_unknown_handle)
172 pr_info("SELinux: the above unknown classes and permissions will be %s\n",
173 pol->allow_unknown ? "allowed" : "denied");
174
175 out_map->size = i;
176 return 0;
177err:
178 kfree(out_map->mapping);
179 out_map->mapping = NULL;
180 return -EINVAL;
181}
182
183/*
184 * Get real, policy values from mapped values
185 */
186
187static u16 unmap_class(struct selinux_map *map, u16 tclass)
188{
189 if (tclass < map->size)
190 return map->mapping[tclass].value;
191
192 return tclass;
193}
194
195/*
196 * Get kernel value for class from its policy value
197 */
198static u16 map_class(struct selinux_map *map, u16 pol_value)
199{
200 u16 i;
201
202 for (i = 1; i < map->size; i++) {
203 if (map->mapping[i].value == pol_value)
204 return i;
205 }
206
207 return SECCLASS_NULL;
208}
209
210static void map_decision(struct selinux_map *map,
211 u16 tclass, struct av_decision *avd,
212 int allow_unknown)
213{
214 if (tclass < map->size) {
215 struct selinux_mapping *mapping = &map->mapping[tclass];
216 unsigned int i, n = mapping->num_perms;
217 u32 result;
218
219 for (i = 0, result = 0; i < n; i++) {
220 if (avd->allowed & mapping->perms[i])
221 result |= 1<<i;
222 if (allow_unknown && !mapping->perms[i])
223 result |= 1<<i;
224 }
225 avd->allowed = result;
226
227 for (i = 0, result = 0; i < n; i++)
228 if (avd->auditallow & mapping->perms[i])
229 result |= 1<<i;
230 avd->auditallow = result;
231
232 for (i = 0, result = 0; i < n; i++) {
233 if (avd->auditdeny & mapping->perms[i])
234 result |= 1<<i;
235 if (!allow_unknown && !mapping->perms[i])
236 result |= 1<<i;
237 }
238 /*
239 * In case the kernel has a bug and requests a permission
240 * between num_perms and the maximum permission number, we
241 * should audit that denial
242 */
243 for (; i < (sizeof(u32)*8); i++)
244 result |= 1<<i;
245 avd->auditdeny = result;
246 }
247}
248
249int security_mls_enabled(struct selinux_state *state)
250{
251 struct policydb *p = &state->ss->policydb;
252
253 return p->mls_enabled;
254}
255
256/*
257 * Return the boolean value of a constraint expression
258 * when it is applied to the specified source and target
259 * security contexts.
260 *
261 * xcontext is a special beast... It is used by the validatetrans rules
262 * only. For these rules, scontext is the context before the transition,
263 * tcontext is the context after the transition, and xcontext is the context
264 * of the process performing the transition. All other callers of
265 * constraint_expr_eval should pass in NULL for xcontext.
266 */
267static int constraint_expr_eval(struct policydb *policydb,
268 struct context *scontext,
269 struct context *tcontext,
270 struct context *xcontext,
271 struct constraint_expr *cexpr)
272{
273 u32 val1, val2;
274 struct context *c;
275 struct role_datum *r1, *r2;
276 struct mls_level *l1, *l2;
277 struct constraint_expr *e;
278 int s[CEXPR_MAXDEPTH];
279 int sp = -1;
280
281 for (e = cexpr; e; e = e->next) {
282 switch (e->expr_type) {
283 case CEXPR_NOT:
284 BUG_ON(sp < 0);
285 s[sp] = !s[sp];
286 break;
287 case CEXPR_AND:
288 BUG_ON(sp < 1);
289 sp--;
290 s[sp] &= s[sp + 1];
291 break;
292 case CEXPR_OR:
293 BUG_ON(sp < 1);
294 sp--;
295 s[sp] |= s[sp + 1];
296 break;
297 case CEXPR_ATTR:
298 if (sp == (CEXPR_MAXDEPTH - 1))
299 return 0;
300 switch (e->attr) {
301 case CEXPR_USER:
302 val1 = scontext->user;
303 val2 = tcontext->user;
304 break;
305 case CEXPR_TYPE:
306 val1 = scontext->type;
307 val2 = tcontext->type;
308 break;
309 case CEXPR_ROLE:
310 val1 = scontext->role;
311 val2 = tcontext->role;
312 r1 = policydb->role_val_to_struct[val1 - 1];
313 r2 = policydb->role_val_to_struct[val2 - 1];
314 switch (e->op) {
315 case CEXPR_DOM:
316 s[++sp] = ebitmap_get_bit(&r1->dominates,
317 val2 - 1);
318 continue;
319 case CEXPR_DOMBY:
320 s[++sp] = ebitmap_get_bit(&r2->dominates,
321 val1 - 1);
322 continue;
323 case CEXPR_INCOMP:
324 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
325 val2 - 1) &&
326 !ebitmap_get_bit(&r2->dominates,
327 val1 - 1));
328 continue;
329 default:
330 break;
331 }
332 break;
333 case CEXPR_L1L2:
334 l1 = &(scontext->range.level[0]);
335 l2 = &(tcontext->range.level[0]);
336 goto mls_ops;
337 case CEXPR_L1H2:
338 l1 = &(scontext->range.level[0]);
339 l2 = &(tcontext->range.level[1]);
340 goto mls_ops;
341 case CEXPR_H1L2:
342 l1 = &(scontext->range.level[1]);
343 l2 = &(tcontext->range.level[0]);
344 goto mls_ops;
345 case CEXPR_H1H2:
346 l1 = &(scontext->range.level[1]);
347 l2 = &(tcontext->range.level[1]);
348 goto mls_ops;
349 case CEXPR_L1H1:
350 l1 = &(scontext->range.level[0]);
351 l2 = &(scontext->range.level[1]);
352 goto mls_ops;
353 case CEXPR_L2H2:
354 l1 = &(tcontext->range.level[0]);
355 l2 = &(tcontext->range.level[1]);
356 goto mls_ops;
357mls_ops:
358 switch (e->op) {
359 case CEXPR_EQ:
360 s[++sp] = mls_level_eq(l1, l2);
361 continue;
362 case CEXPR_NEQ:
363 s[++sp] = !mls_level_eq(l1, l2);
364 continue;
365 case CEXPR_DOM:
366 s[++sp] = mls_level_dom(l1, l2);
367 continue;
368 case CEXPR_DOMBY:
369 s[++sp] = mls_level_dom(l2, l1);
370 continue;
371 case CEXPR_INCOMP:
372 s[++sp] = mls_level_incomp(l2, l1);
373 continue;
374 default:
375 BUG();
376 return 0;
377 }
378 break;
379 default:
380 BUG();
381 return 0;
382 }
383
384 switch (e->op) {
385 case CEXPR_EQ:
386 s[++sp] = (val1 == val2);
387 break;
388 case CEXPR_NEQ:
389 s[++sp] = (val1 != val2);
390 break;
391 default:
392 BUG();
393 return 0;
394 }
395 break;
396 case CEXPR_NAMES:
397 if (sp == (CEXPR_MAXDEPTH-1))
398 return 0;
399 c = scontext;
400 if (e->attr & CEXPR_TARGET)
401 c = tcontext;
402 else if (e->attr & CEXPR_XTARGET) {
403 c = xcontext;
404 if (!c) {
405 BUG();
406 return 0;
407 }
408 }
409 if (e->attr & CEXPR_USER)
410 val1 = c->user;
411 else if (e->attr & CEXPR_ROLE)
412 val1 = c->role;
413 else if (e->attr & CEXPR_TYPE)
414 val1 = c->type;
415 else {
416 BUG();
417 return 0;
418 }
419
420 switch (e->op) {
421 case CEXPR_EQ:
422 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
423 break;
424 case CEXPR_NEQ:
425 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
426 break;
427 default:
428 BUG();
429 return 0;
430 }
431 break;
432 default:
433 BUG();
434 return 0;
435 }
436 }
437
438 BUG_ON(sp != 0);
439 return s[0];
440}
441
442/*
443 * security_dump_masked_av - dumps masked permissions during
444 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
445 */
446static int dump_masked_av_helper(void *k, void *d, void *args)
447{
448 struct perm_datum *pdatum = d;
449 char **permission_names = args;
450
451 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
452
453 permission_names[pdatum->value - 1] = (char *)k;
454
455 return 0;
456}
457
458static void security_dump_masked_av(struct policydb *policydb,
459 struct context *scontext,
460 struct context *tcontext,
461 u16 tclass,
462 u32 permissions,
463 const char *reason)
464{
465 struct common_datum *common_dat;
466 struct class_datum *tclass_dat;
467 struct audit_buffer *ab;
468 char *tclass_name;
469 char *scontext_name = NULL;
470 char *tcontext_name = NULL;
471 char *permission_names[32];
472 int index;
473 u32 length;
474 bool need_comma = false;
475
476 if (!permissions)
477 return;
478
479 tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1);
480 tclass_dat = policydb->class_val_to_struct[tclass - 1];
481 common_dat = tclass_dat->comdatum;
482
483 /* init permission_names */
484 if (common_dat &&
485 hashtab_map(&common_dat->permissions.table,
486 dump_masked_av_helper, permission_names) < 0)
487 goto out;
488
489 if (hashtab_map(&tclass_dat->permissions.table,
490 dump_masked_av_helper, permission_names) < 0)
491 goto out;
492
493 /* get scontext/tcontext in text form */
494 if (context_struct_to_string(policydb, scontext,
495 &scontext_name, &length) < 0)
496 goto out;
497
498 if (context_struct_to_string(policydb, tcontext,
499 &tcontext_name, &length) < 0)
500 goto out;
501
502 /* audit a message */
503 ab = audit_log_start(audit_context(),
504 GFP_ATOMIC, AUDIT_SELINUX_ERR);
505 if (!ab)
506 goto out;
507
508 audit_log_format(ab, "op=security_compute_av reason=%s "
509 "scontext=%s tcontext=%s tclass=%s perms=",
510 reason, scontext_name, tcontext_name, tclass_name);
511
512 for (index = 0; index < 32; index++) {
513 u32 mask = (1 << index);
514
515 if ((mask & permissions) == 0)
516 continue;
517
518 audit_log_format(ab, "%s%s",
519 need_comma ? "," : "",
520 permission_names[index]
521 ? permission_names[index] : "????");
522 need_comma = true;
523 }
524 audit_log_end(ab);
525out:
526 /* release scontext/tcontext */
527 kfree(tcontext_name);
528 kfree(scontext_name);
529
530 return;
531}
532
533/*
534 * security_boundary_permission - drops violated permissions
535 * on boundary constraint.
536 */
537static void type_attribute_bounds_av(struct policydb *policydb,
538 struct context *scontext,
539 struct context *tcontext,
540 u16 tclass,
541 struct av_decision *avd)
542{
543 struct context lo_scontext;
544 struct context lo_tcontext, *tcontextp = tcontext;
545 struct av_decision lo_avd;
546 struct type_datum *source;
547 struct type_datum *target;
548 u32 masked = 0;
549
550 source = policydb->type_val_to_struct[scontext->type - 1];
551 BUG_ON(!source);
552
553 if (!source->bounds)
554 return;
555
556 target = policydb->type_val_to_struct[tcontext->type - 1];
557 BUG_ON(!target);
558
559 memset(&lo_avd, 0, sizeof(lo_avd));
560
561 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
562 lo_scontext.type = source->bounds;
563
564 if (target->bounds) {
565 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
566 lo_tcontext.type = target->bounds;
567 tcontextp = &lo_tcontext;
568 }
569
570 context_struct_compute_av(policydb, &lo_scontext,
571 tcontextp,
572 tclass,
573 &lo_avd,
574 NULL);
575
576 masked = ~lo_avd.allowed & avd->allowed;
577
578 if (likely(!masked))
579 return; /* no masked permission */
580
581 /* mask violated permissions */
582 avd->allowed &= ~masked;
583
584 /* audit masked permissions */
585 security_dump_masked_av(policydb, scontext, tcontext,
586 tclass, masked, "bounds");
587}
588
589/*
590 * flag which drivers have permissions
591 * only looking for ioctl based extended permssions
592 */
593void services_compute_xperms_drivers(
594 struct extended_perms *xperms,
595 struct avtab_node *node)
596{
597 unsigned int i;
598
599 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
600 /* if one or more driver has all permissions allowed */
601 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
602 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
603 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
604 /* if allowing permissions within a driver */
605 security_xperm_set(xperms->drivers.p,
606 node->datum.u.xperms->driver);
607 }
608
609 /* If no ioctl commands are allowed, ignore auditallow and auditdeny */
610 if (node->key.specified & AVTAB_XPERMS_ALLOWED)
611 xperms->len = 1;
612}
613
614/*
615 * Compute access vectors and extended permissions based on a context
616 * structure pair for the permissions in a particular class.
617 */
618static void context_struct_compute_av(struct policydb *policydb,
619 struct context *scontext,
620 struct context *tcontext,
621 u16 tclass,
622 struct av_decision *avd,
623 struct extended_perms *xperms)
624{
625 struct constraint_node *constraint;
626 struct role_allow *ra;
627 struct avtab_key avkey;
628 struct avtab_node *node;
629 struct class_datum *tclass_datum;
630 struct ebitmap *sattr, *tattr;
631 struct ebitmap_node *snode, *tnode;
632 unsigned int i, j;
633
634 avd->allowed = 0;
635 avd->auditallow = 0;
636 avd->auditdeny = 0xffffffff;
637 if (xperms) {
638 memset(&xperms->drivers, 0, sizeof(xperms->drivers));
639 xperms->len = 0;
640 }
641
642 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
643 if (printk_ratelimit())
644 pr_warn("SELinux: Invalid class %hu\n", tclass);
645 return;
646 }
647
648 tclass_datum = policydb->class_val_to_struct[tclass - 1];
649
650 /*
651 * If a specific type enforcement rule was defined for
652 * this permission check, then use it.
653 */
654 avkey.target_class = tclass;
655 avkey.specified = AVTAB_AV | AVTAB_XPERMS;
656 sattr = &policydb->type_attr_map_array[scontext->type - 1];
657 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
658 ebitmap_for_each_positive_bit(sattr, snode, i) {
659 ebitmap_for_each_positive_bit(tattr, tnode, j) {
660 avkey.source_type = i + 1;
661 avkey.target_type = j + 1;
662 for (node = avtab_search_node(&policydb->te_avtab,
663 &avkey);
664 node;
665 node = avtab_search_node_next(node, avkey.specified)) {
666 if (node->key.specified == AVTAB_ALLOWED)
667 avd->allowed |= node->datum.u.data;
668 else if (node->key.specified == AVTAB_AUDITALLOW)
669 avd->auditallow |= node->datum.u.data;
670 else if (node->key.specified == AVTAB_AUDITDENY)
671 avd->auditdeny &= node->datum.u.data;
672 else if (xperms && (node->key.specified & AVTAB_XPERMS))
673 services_compute_xperms_drivers(xperms, node);
674 }
675
676 /* Check conditional av table for additional permissions */
677 cond_compute_av(&policydb->te_cond_avtab, &avkey,
678 avd, xperms);
679
680 }
681 }
682
683 /*
684 * Remove any permissions prohibited by a constraint (this includes
685 * the MLS policy).
686 */
687 constraint = tclass_datum->constraints;
688 while (constraint) {
689 if ((constraint->permissions & (avd->allowed)) &&
690 !constraint_expr_eval(policydb, scontext, tcontext, NULL,
691 constraint->expr)) {
692 avd->allowed &= ~(constraint->permissions);
693 }
694 constraint = constraint->next;
695 }
696
697 /*
698 * If checking process transition permission and the
699 * role is changing, then check the (current_role, new_role)
700 * pair.
701 */
702 if (tclass == policydb->process_class &&
703 (avd->allowed & policydb->process_trans_perms) &&
704 scontext->role != tcontext->role) {
705 for (ra = policydb->role_allow; ra; ra = ra->next) {
706 if (scontext->role == ra->role &&
707 tcontext->role == ra->new_role)
708 break;
709 }
710 if (!ra)
711 avd->allowed &= ~policydb->process_trans_perms;
712 }
713
714 /*
715 * If the given source and target types have boundary
716 * constraint, lazy checks have to mask any violated
717 * permission and notice it to userspace via audit.
718 */
719 type_attribute_bounds_av(policydb, scontext, tcontext,
720 tclass, avd);
721}
722
723static int security_validtrans_handle_fail(struct selinux_state *state,
724 struct sidtab_entry *oentry,
725 struct sidtab_entry *nentry,
726 struct sidtab_entry *tentry,
727 u16 tclass)
728{
729 struct policydb *p = &state->ss->policydb;
730 struct sidtab *sidtab = state->ss->sidtab;
731 char *o = NULL, *n = NULL, *t = NULL;
732 u32 olen, nlen, tlen;
733
734 if (sidtab_entry_to_string(p, sidtab, oentry, &o, &olen))
735 goto out;
736 if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen))
737 goto out;
738 if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen))
739 goto out;
740 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
741 "op=security_validate_transition seresult=denied"
742 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
743 o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
744out:
745 kfree(o);
746 kfree(n);
747 kfree(t);
748
749 if (!enforcing_enabled(state))
750 return 0;
751 return -EPERM;
752}
753
754static int security_compute_validatetrans(struct selinux_state *state,
755 u32 oldsid, u32 newsid, u32 tasksid,
756 u16 orig_tclass, bool user)
757{
758 struct policydb *policydb;
759 struct sidtab *sidtab;
760 struct sidtab_entry *oentry;
761 struct sidtab_entry *nentry;
762 struct sidtab_entry *tentry;
763 struct class_datum *tclass_datum;
764 struct constraint_node *constraint;
765 u16 tclass;
766 int rc = 0;
767
768
769 if (!selinux_initialized(state))
770 return 0;
771
772 read_lock(&state->ss->policy_rwlock);
773
774 policydb = &state->ss->policydb;
775 sidtab = state->ss->sidtab;
776
777 if (!user)
778 tclass = unmap_class(&state->ss->map, orig_tclass);
779 else
780 tclass = orig_tclass;
781
782 if (!tclass || tclass > policydb->p_classes.nprim) {
783 rc = -EINVAL;
784 goto out;
785 }
786 tclass_datum = policydb->class_val_to_struct[tclass - 1];
787
788 oentry = sidtab_search_entry(sidtab, oldsid);
789 if (!oentry) {
790 pr_err("SELinux: %s: unrecognized SID %d\n",
791 __func__, oldsid);
792 rc = -EINVAL;
793 goto out;
794 }
795
796 nentry = sidtab_search_entry(sidtab, newsid);
797 if (!nentry) {
798 pr_err("SELinux: %s: unrecognized SID %d\n",
799 __func__, newsid);
800 rc = -EINVAL;
801 goto out;
802 }
803
804 tentry = sidtab_search_entry(sidtab, tasksid);
805 if (!tentry) {
806 pr_err("SELinux: %s: unrecognized SID %d\n",
807 __func__, tasksid);
808 rc = -EINVAL;
809 goto out;
810 }
811
812 constraint = tclass_datum->validatetrans;
813 while (constraint) {
814 if (!constraint_expr_eval(policydb, &oentry->context,
815 &nentry->context, &tentry->context,
816 constraint->expr)) {
817 if (user)
818 rc = -EPERM;
819 else
820 rc = security_validtrans_handle_fail(state,
821 oentry,
822 nentry,
823 tentry,
824 tclass);
825 goto out;
826 }
827 constraint = constraint->next;
828 }
829
830out:
831 read_unlock(&state->ss->policy_rwlock);
832 return rc;
833}
834
835int security_validate_transition_user(struct selinux_state *state,
836 u32 oldsid, u32 newsid, u32 tasksid,
837 u16 tclass)
838{
839 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
840 tclass, true);
841}
842
843int security_validate_transition(struct selinux_state *state,
844 u32 oldsid, u32 newsid, u32 tasksid,
845 u16 orig_tclass)
846{
847 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
848 orig_tclass, false);
849}
850
851/*
852 * security_bounded_transition - check whether the given
853 * transition is directed to bounded, or not.
854 * It returns 0, if @newsid is bounded by @oldsid.
855 * Otherwise, it returns error code.
856 *
857 * @oldsid : current security identifier
858 * @newsid : destinated security identifier
859 */
860int security_bounded_transition(struct selinux_state *state,
861 u32 old_sid, u32 new_sid)
862{
863 struct policydb *policydb;
864 struct sidtab *sidtab;
865 struct sidtab_entry *old_entry, *new_entry;
866 struct type_datum *type;
867 int index;
868 int rc;
869
870 if (!selinux_initialized(state))
871 return 0;
872
873 read_lock(&state->ss->policy_rwlock);
874
875 policydb = &state->ss->policydb;
876 sidtab = state->ss->sidtab;
877
878 rc = -EINVAL;
879 old_entry = sidtab_search_entry(sidtab, old_sid);
880 if (!old_entry) {
881 pr_err("SELinux: %s: unrecognized SID %u\n",
882 __func__, old_sid);
883 goto out;
884 }
885
886 rc = -EINVAL;
887 new_entry = sidtab_search_entry(sidtab, new_sid);
888 if (!new_entry) {
889 pr_err("SELinux: %s: unrecognized SID %u\n",
890 __func__, new_sid);
891 goto out;
892 }
893
894 rc = 0;
895 /* type/domain unchanged */
896 if (old_entry->context.type == new_entry->context.type)
897 goto out;
898
899 index = new_entry->context.type;
900 while (true) {
901 type = policydb->type_val_to_struct[index - 1];
902 BUG_ON(!type);
903
904 /* not bounded anymore */
905 rc = -EPERM;
906 if (!type->bounds)
907 break;
908
909 /* @newsid is bounded by @oldsid */
910 rc = 0;
911 if (type->bounds == old_entry->context.type)
912 break;
913
914 index = type->bounds;
915 }
916
917 if (rc) {
918 char *old_name = NULL;
919 char *new_name = NULL;
920 u32 length;
921
922 if (!sidtab_entry_to_string(policydb, sidtab, old_entry,
923 &old_name, &length) &&
924 !sidtab_entry_to_string(policydb, sidtab, new_entry,
925 &new_name, &length)) {
926 audit_log(audit_context(),
927 GFP_ATOMIC, AUDIT_SELINUX_ERR,
928 "op=security_bounded_transition "
929 "seresult=denied "
930 "oldcontext=%s newcontext=%s",
931 old_name, new_name);
932 }
933 kfree(new_name);
934 kfree(old_name);
935 }
936out:
937 read_unlock(&state->ss->policy_rwlock);
938
939 return rc;
940}
941
942static void avd_init(struct selinux_state *state, struct av_decision *avd)
943{
944 avd->allowed = 0;
945 avd->auditallow = 0;
946 avd->auditdeny = 0xffffffff;
947 avd->seqno = state->ss->latest_granting;
948 avd->flags = 0;
949}
950
951void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
952 struct avtab_node *node)
953{
954 unsigned int i;
955
956 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
957 if (xpermd->driver != node->datum.u.xperms->driver)
958 return;
959 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
960 if (!security_xperm_test(node->datum.u.xperms->perms.p,
961 xpermd->driver))
962 return;
963 } else {
964 BUG();
965 }
966
967 if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
968 xpermd->used |= XPERMS_ALLOWED;
969 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
970 memset(xpermd->allowed->p, 0xff,
971 sizeof(xpermd->allowed->p));
972 }
973 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
974 for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++)
975 xpermd->allowed->p[i] |=
976 node->datum.u.xperms->perms.p[i];
977 }
978 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
979 xpermd->used |= XPERMS_AUDITALLOW;
980 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
981 memset(xpermd->auditallow->p, 0xff,
982 sizeof(xpermd->auditallow->p));
983 }
984 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
985 for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++)
986 xpermd->auditallow->p[i] |=
987 node->datum.u.xperms->perms.p[i];
988 }
989 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
990 xpermd->used |= XPERMS_DONTAUDIT;
991 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
992 memset(xpermd->dontaudit->p, 0xff,
993 sizeof(xpermd->dontaudit->p));
994 }
995 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
996 for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++)
997 xpermd->dontaudit->p[i] |=
998 node->datum.u.xperms->perms.p[i];
999 }
1000 } else {
1001 BUG();
1002 }
1003}
1004
1005void security_compute_xperms_decision(struct selinux_state *state,
1006 u32 ssid,
1007 u32 tsid,
1008 u16 orig_tclass,
1009 u8 driver,
1010 struct extended_perms_decision *xpermd)
1011{
1012 struct policydb *policydb;
1013 struct sidtab *sidtab;
1014 u16 tclass;
1015 struct context *scontext, *tcontext;
1016 struct avtab_key avkey;
1017 struct avtab_node *node;
1018 struct ebitmap *sattr, *tattr;
1019 struct ebitmap_node *snode, *tnode;
1020 unsigned int i, j;
1021
1022 xpermd->driver = driver;
1023 xpermd->used = 0;
1024 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1025 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1026 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1027
1028 read_lock(&state->ss->policy_rwlock);
1029 if (!selinux_initialized(state))
1030 goto allow;
1031
1032 policydb = &state->ss->policydb;
1033 sidtab = state->ss->sidtab;
1034
1035 scontext = sidtab_search(sidtab, ssid);
1036 if (!scontext) {
1037 pr_err("SELinux: %s: unrecognized SID %d\n",
1038 __func__, ssid);
1039 goto out;
1040 }
1041
1042 tcontext = sidtab_search(sidtab, tsid);
1043 if (!tcontext) {
1044 pr_err("SELinux: %s: unrecognized SID %d\n",
1045 __func__, tsid);
1046 goto out;
1047 }
1048
1049 tclass = unmap_class(&state->ss->map, orig_tclass);
1050 if (unlikely(orig_tclass && !tclass)) {
1051 if (policydb->allow_unknown)
1052 goto allow;
1053 goto out;
1054 }
1055
1056
1057 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1058 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1059 goto out;
1060 }
1061
1062 avkey.target_class = tclass;
1063 avkey.specified = AVTAB_XPERMS;
1064 sattr = &policydb->type_attr_map_array[scontext->type - 1];
1065 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
1066 ebitmap_for_each_positive_bit(sattr, snode, i) {
1067 ebitmap_for_each_positive_bit(tattr, tnode, j) {
1068 avkey.source_type = i + 1;
1069 avkey.target_type = j + 1;
1070 for (node = avtab_search_node(&policydb->te_avtab,
1071 &avkey);
1072 node;
1073 node = avtab_search_node_next(node, avkey.specified))
1074 services_compute_xperms_decision(xpermd, node);
1075
1076 cond_compute_xperms(&policydb->te_cond_avtab,
1077 &avkey, xpermd);
1078 }
1079 }
1080out:
1081 read_unlock(&state->ss->policy_rwlock);
1082 return;
1083allow:
1084 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1085 goto out;
1086}
1087
1088/**
1089 * security_compute_av - Compute access vector decisions.
1090 * @ssid: source security identifier
1091 * @tsid: target security identifier
1092 * @tclass: target security class
1093 * @avd: access vector decisions
1094 * @xperms: extended permissions
1095 *
1096 * Compute a set of access vector decisions based on the
1097 * SID pair (@ssid, @tsid) for the permissions in @tclass.
1098 */
1099void security_compute_av(struct selinux_state *state,
1100 u32 ssid,
1101 u32 tsid,
1102 u16 orig_tclass,
1103 struct av_decision *avd,
1104 struct extended_perms *xperms)
1105{
1106 struct policydb *policydb;
1107 struct sidtab *sidtab;
1108 u16 tclass;
1109 struct context *scontext = NULL, *tcontext = NULL;
1110
1111 read_lock(&state->ss->policy_rwlock);
1112 avd_init(state, avd);
1113 xperms->len = 0;
1114 if (!selinux_initialized(state))
1115 goto allow;
1116
1117 policydb = &state->ss->policydb;
1118 sidtab = state->ss->sidtab;
1119
1120 scontext = sidtab_search(sidtab, ssid);
1121 if (!scontext) {
1122 pr_err("SELinux: %s: unrecognized SID %d\n",
1123 __func__, ssid);
1124 goto out;
1125 }
1126
1127 /* permissive domain? */
1128 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1129 avd->flags |= AVD_FLAGS_PERMISSIVE;
1130
1131 tcontext = sidtab_search(sidtab, tsid);
1132 if (!tcontext) {
1133 pr_err("SELinux: %s: unrecognized SID %d\n",
1134 __func__, tsid);
1135 goto out;
1136 }
1137
1138 tclass = unmap_class(&state->ss->map, orig_tclass);
1139 if (unlikely(orig_tclass && !tclass)) {
1140 if (policydb->allow_unknown)
1141 goto allow;
1142 goto out;
1143 }
1144 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1145 xperms);
1146 map_decision(&state->ss->map, orig_tclass, avd,
1147 policydb->allow_unknown);
1148out:
1149 read_unlock(&state->ss->policy_rwlock);
1150 return;
1151allow:
1152 avd->allowed = 0xffffffff;
1153 goto out;
1154}
1155
1156void security_compute_av_user(struct selinux_state *state,
1157 u32 ssid,
1158 u32 tsid,
1159 u16 tclass,
1160 struct av_decision *avd)
1161{
1162 struct policydb *policydb;
1163 struct sidtab *sidtab;
1164 struct context *scontext = NULL, *tcontext = NULL;
1165
1166 read_lock(&state->ss->policy_rwlock);
1167 avd_init(state, avd);
1168 if (!selinux_initialized(state))
1169 goto allow;
1170
1171 policydb = &state->ss->policydb;
1172 sidtab = state->ss->sidtab;
1173
1174 scontext = sidtab_search(sidtab, ssid);
1175 if (!scontext) {
1176 pr_err("SELinux: %s: unrecognized SID %d\n",
1177 __func__, ssid);
1178 goto out;
1179 }
1180
1181 /* permissive domain? */
1182 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1183 avd->flags |= AVD_FLAGS_PERMISSIVE;
1184
1185 tcontext = sidtab_search(sidtab, tsid);
1186 if (!tcontext) {
1187 pr_err("SELinux: %s: unrecognized SID %d\n",
1188 __func__, tsid);
1189 goto out;
1190 }
1191
1192 if (unlikely(!tclass)) {
1193 if (policydb->allow_unknown)
1194 goto allow;
1195 goto out;
1196 }
1197
1198 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1199 NULL);
1200 out:
1201 read_unlock(&state->ss->policy_rwlock);
1202 return;
1203allow:
1204 avd->allowed = 0xffffffff;
1205 goto out;
1206}
1207
1208/*
1209 * Write the security context string representation of
1210 * the context structure `context' into a dynamically
1211 * allocated string of the correct size. Set `*scontext'
1212 * to point to this string and set `*scontext_len' to
1213 * the length of the string.
1214 */
1215static int context_struct_to_string(struct policydb *p,
1216 struct context *context,
1217 char **scontext, u32 *scontext_len)
1218{
1219 char *scontextp;
1220
1221 if (scontext)
1222 *scontext = NULL;
1223 *scontext_len = 0;
1224
1225 if (context->len) {
1226 *scontext_len = context->len;
1227 if (scontext) {
1228 *scontext = kstrdup(context->str, GFP_ATOMIC);
1229 if (!(*scontext))
1230 return -ENOMEM;
1231 }
1232 return 0;
1233 }
1234
1235 /* Compute the size of the context. */
1236 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1237 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1238 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1239 *scontext_len += mls_compute_context_len(p, context);
1240
1241 if (!scontext)
1242 return 0;
1243
1244 /* Allocate space for the context; caller must free this space. */
1245 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1246 if (!scontextp)
1247 return -ENOMEM;
1248 *scontext = scontextp;
1249
1250 /*
1251 * Copy the user name, role name and type name into the context.
1252 */
1253 scontextp += sprintf(scontextp, "%s:%s:%s",
1254 sym_name(p, SYM_USERS, context->user - 1),
1255 sym_name(p, SYM_ROLES, context->role - 1),
1256 sym_name(p, SYM_TYPES, context->type - 1));
1257
1258 mls_sid_to_context(p, context, &scontextp);
1259
1260 *scontextp = 0;
1261
1262 return 0;
1263}
1264
1265static int sidtab_entry_to_string(struct policydb *p,
1266 struct sidtab *sidtab,
1267 struct sidtab_entry *entry,
1268 char **scontext, u32 *scontext_len)
1269{
1270 int rc = sidtab_sid2str_get(sidtab, entry, scontext, scontext_len);
1271
1272 if (rc != -ENOENT)
1273 return rc;
1274
1275 rc = context_struct_to_string(p, &entry->context, scontext,
1276 scontext_len);
1277 if (!rc && scontext)
1278 sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len);
1279 return rc;
1280}
1281
1282#include "initial_sid_to_string.h"
1283
1284int security_sidtab_hash_stats(struct selinux_state *state, char *page)
1285{
1286 int rc;
1287
1288 if (!selinux_initialized(state)) {
1289 pr_err("SELinux: %s: called before initial load_policy\n",
1290 __func__);
1291 return -EINVAL;
1292 }
1293
1294 read_lock(&state->ss->policy_rwlock);
1295 rc = sidtab_hash_stats(state->ss->sidtab, page);
1296 read_unlock(&state->ss->policy_rwlock);
1297
1298 return rc;
1299}
1300
1301const 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
1308static int security_sid_to_context_core(struct selinux_state *state,
1309 u32 sid, char **scontext,
1310 u32 *scontext_len, int force,
1311 int only_invalid)
1312{
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(state)) {
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(s, *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 read_lock(&state->ss->policy_rwlock);
1343 policydb = &state->ss->policydb;
1344 sidtab = state->ss->sidtab;
1345
1346 if (force)
1347 entry = sidtab_search_entry_force(sidtab, sid);
1348 else
1349 entry = sidtab_search_entry(sidtab, sid);
1350 if (!entry) {
1351 pr_err("SELinux: %s: unrecognized SID %d\n",
1352 __func__, sid);
1353 rc = -EINVAL;
1354 goto out_unlock;
1355 }
1356 if (only_invalid && !entry->context.len)
1357 goto out_unlock;
1358
1359 rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext,
1360 scontext_len);
1361
1362out_unlock:
1363 read_unlock(&state->ss->policy_rwlock);
1364 return rc;
1365
1366}
1367
1368/**
1369 * security_sid_to_context - Obtain a context for a given SID.
1370 * @sid: security identifier, SID
1371 * @scontext: security context
1372 * @scontext_len: length in bytes
1373 *
1374 * Write the string representation of the context associated with @sid
1375 * into a dynamically allocated string of the correct size. Set @scontext
1376 * to point to this string and set @scontext_len to the length of the string.
1377 */
1378int security_sid_to_context(struct selinux_state *state,
1379 u32 sid, char **scontext, u32 *scontext_len)
1380{
1381 return security_sid_to_context_core(state, sid, scontext,
1382 scontext_len, 0, 0);
1383}
1384
1385int security_sid_to_context_force(struct selinux_state *state, u32 sid,
1386 char **scontext, u32 *scontext_len)
1387{
1388 return security_sid_to_context_core(state, sid, scontext,
1389 scontext_len, 1, 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 */
1405int security_sid_to_context_inval(struct selinux_state *state, u32 sid,
1406 char **scontext, u32 *scontext_len)
1407{
1408 return security_sid_to_context_core(state, sid, scontext,
1409 scontext_len, 1, 1);
1410}
1411
1412/*
1413 * Caveat: Mutates scontext.
1414 */
1415static 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(ctx);
1428
1429 /* Parse the security context. */
1430
1431 rc = -EINVAL;
1432 scontextp = (char *) 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(&pol->p_users, 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(&pol->p_roles, 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(&pol->p_types, scontextp);
1473 if (!typdatum || typdatum->attribute)
1474 goto out;
1475
1476 ctx->type = typdatum->value;
1477
1478 rc = mls_context_to_sid(pol, oldc, p, ctx, 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(pol, ctx))
1485 goto out;
1486 rc = 0;
1487out:
1488 if (rc)
1489 context_destroy(ctx);
1490 return rc;
1491}
1492
1493static int security_context_to_sid_core(struct selinux_state *state,
1494 const char *scontext, u32 scontext_len,
1495 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1496 int force)
1497{
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(scontext, scontext_len, gfp_flags);
1510 if (!scontext2)
1511 return -ENOMEM;
1512
1513 if (!selinux_initialized(state)) {
1514 int 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(scontext2, gfp_flags);
1533 if (!str)
1534 goto out;
1535 }
1536 read_lock(&state->ss->policy_rwlock);
1537 policydb = &state->ss->policydb;
1538 sidtab = state->ss->sidtab;
1539 rc = string_to_context_struct(policydb, sidtab, scontext2,
1540 &context, def_sid);
1541 if (rc == -EINVAL && force) {
1542 context.str = str;
1543 context.len = strlen(str) + 1;
1544 str = NULL;
1545 } else if (rc)
1546 goto out_unlock;
1547 rc = sidtab_context_to_sid(sidtab, &context, sid);
1548 context_destroy(&context);
1549out_unlock:
1550 read_unlock(&state->ss->policy_rwlock);
1551out:
1552 kfree(scontext2);
1553 kfree(str);
1554 return rc;
1555}
1556
1557/**
1558 * security_context_to_sid - Obtain a SID for a given security context.
1559 * @scontext: security context
1560 * @scontext_len: length in bytes
1561 * @sid: security identifier, SID
1562 * @gfp: context for the allocation
1563 *
1564 * Obtains a SID associated with the security context that
1565 * has the string representation specified by @scontext.
1566 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1567 * memory is available, or 0 on success.
1568 */
1569int security_context_to_sid(struct selinux_state *state,
1570 const char *scontext, u32 scontext_len, u32 *sid,
1571 gfp_t gfp)
1572{
1573 return security_context_to_sid_core(state, scontext, scontext_len,
1574 sid, SECSID_NULL, gfp, 0);
1575}
1576
1577int security_context_str_to_sid(struct selinux_state *state,
1578 const char *scontext, u32 *sid, gfp_t gfp)
1579{
1580 return security_context_to_sid(state, scontext, strlen(scontext),
1581 sid, gfp);
1582}
1583
1584/**
1585 * security_context_to_sid_default - Obtain a SID for a given security context,
1586 * falling back to specified default if needed.
1587 *
1588 * @scontext: security context
1589 * @scontext_len: length in bytes
1590 * @sid: security identifier, SID
1591 * @def_sid: default SID to assign on error
1592 *
1593 * Obtains a SID associated with the security context that
1594 * has the string representation specified by @scontext.
1595 * The default SID is passed to the MLS layer to be used to allow
1596 * kernel labeling of the MLS field if the MLS field is not present
1597 * (for upgrading to MLS without full relabel).
1598 * Implicitly forces adding of the context even if it cannot be mapped yet.
1599 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1600 * memory is available, or 0 on success.
1601 */
1602int security_context_to_sid_default(struct selinux_state *state,
1603 const char *scontext, u32 scontext_len,
1604 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1605{
1606 return security_context_to_sid_core(state, scontext, scontext_len,
1607 sid, def_sid, gfp_flags, 1);
1608}
1609
1610int security_context_to_sid_force(struct selinux_state *state,
1611 const char *scontext, u32 scontext_len,
1612 u32 *sid)
1613{
1614 return security_context_to_sid_core(state, scontext, scontext_len,
1615 sid, SECSID_NULL, GFP_KERNEL, 1);
1616}
1617
1618static int compute_sid_handle_invalid_context(
1619 struct selinux_state *state,
1620 struct sidtab_entry *sentry,
1621 struct sidtab_entry *tentry,
1622 u16 tclass,
1623 struct context *newcontext)
1624{
1625 struct policydb *policydb = &state->ss->policydb;
1626 struct sidtab *sidtab = state->ss->sidtab;
1627 char *s = NULL, *t = NULL, *n = NULL;
1628 u32 slen, tlen, nlen;
1629 struct audit_buffer *ab;
1630
1631 if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen))
1632 goto out;
1633 if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen))
1634 goto out;
1635 if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1636 goto out;
1637 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR);
1638 audit_log_format(ab,
1639 "op=security_compute_sid invalid_context=");
1640 /* no need to record the NUL with untrusted strings */
1641 audit_log_n_untrustedstring(ab, n, nlen - 1);
1642 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s",
1643 s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1644 audit_log_end(ab);
1645out:
1646 kfree(s);
1647 kfree(t);
1648 kfree(n);
1649 if (!enforcing_enabled(state))
1650 return 0;
1651 return -EACCES;
1652}
1653
1654static void filename_compute_type(struct policydb *policydb,
1655 struct context *newcontext,
1656 u32 stype, u32 ttype, u16 tclass,
1657 const char *objname)
1658{
1659 struct filename_trans_key ft;
1660 struct filename_trans_datum *datum;
1661
1662 /*
1663 * Most filename trans rules are going to live in specific directories
1664 * like /dev or /var/run. This bitmap will quickly skip rule searches
1665 * if the ttype does not contain any rules.
1666 */
1667 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1668 return;
1669
1670 ft.ttype = ttype;
1671 ft.tclass = tclass;
1672 ft.name = objname;
1673
1674 datum = policydb_filenametr_search(policydb, &ft);
1675 while (datum) {
1676 if (ebitmap_get_bit(&datum->stypes, stype - 1)) {
1677 newcontext->type = datum->otype;
1678 return;
1679 }
1680 datum = datum->next;
1681 }
1682}
1683
1684static int security_compute_sid(struct selinux_state *state,
1685 u32 ssid,
1686 u32 tsid,
1687 u16 orig_tclass,
1688 u32 specified,
1689 const char *objname,
1690 u32 *out_sid,
1691 bool kern)
1692{
1693 struct policydb *policydb;
1694 struct sidtab *sidtab;
1695 struct class_datum *cladatum = NULL;
1696 struct context *scontext, *tcontext, newcontext;
1697 struct sidtab_entry *sentry, *tentry;
1698 struct avtab_key avkey;
1699 struct avtab_datum *avdatum;
1700 struct avtab_node *node;
1701 u16 tclass;
1702 int rc = 0;
1703 bool sock;
1704
1705 if (!selinux_initialized(state)) {
1706 switch (orig_tclass) {
1707 case SECCLASS_PROCESS: /* kernel value */
1708 *out_sid = ssid;
1709 break;
1710 default:
1711 *out_sid = tsid;
1712 break;
1713 }
1714 goto out;
1715 }
1716
1717 context_init(&newcontext);
1718
1719 read_lock(&state->ss->policy_rwlock);
1720
1721 if (kern) {
1722 tclass = unmap_class(&state->ss->map, orig_tclass);
1723 sock = security_is_socket_class(orig_tclass);
1724 } else {
1725 tclass = orig_tclass;
1726 sock = security_is_socket_class(map_class(&state->ss->map,
1727 tclass));
1728 }
1729
1730 policydb = &state->ss->policydb;
1731 sidtab = state->ss->sidtab;
1732
1733 sentry = sidtab_search_entry(sidtab, ssid);
1734 if (!sentry) {
1735 pr_err("SELinux: %s: unrecognized SID %d\n",
1736 __func__, ssid);
1737 rc = -EINVAL;
1738 goto out_unlock;
1739 }
1740 tentry = sidtab_search_entry(sidtab, tsid);
1741 if (!tentry) {
1742 pr_err("SELinux: %s: unrecognized SID %d\n",
1743 __func__, tsid);
1744 rc = -EINVAL;
1745 goto out_unlock;
1746 }
1747
1748 scontext = &sentry->context;
1749 tcontext = &tentry->context;
1750
1751 if (tclass && tclass <= policydb->p_classes.nprim)
1752 cladatum = policydb->class_val_to_struct[tclass - 1];
1753
1754 /* Set the user identity. */
1755 switch (specified) {
1756 case AVTAB_TRANSITION:
1757 case AVTAB_CHANGE:
1758 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1759 newcontext.user = tcontext->user;
1760 } else {
1761 /* notice this gets both DEFAULT_SOURCE and unset */
1762 /* Use the process user identity. */
1763 newcontext.user = scontext->user;
1764 }
1765 break;
1766 case AVTAB_MEMBER:
1767 /* Use the related object owner. */
1768 newcontext.user = tcontext->user;
1769 break;
1770 }
1771
1772 /* Set the role to default values. */
1773 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1774 newcontext.role = scontext->role;
1775 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1776 newcontext.role = tcontext->role;
1777 } else {
1778 if ((tclass == policydb->process_class) || sock)
1779 newcontext.role = scontext->role;
1780 else
1781 newcontext.role = OBJECT_R_VAL;
1782 }
1783
1784 /* Set the type to default values. */
1785 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1786 newcontext.type = scontext->type;
1787 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1788 newcontext.type = tcontext->type;
1789 } else {
1790 if ((tclass == policydb->process_class) || sock) {
1791 /* Use the type of process. */
1792 newcontext.type = scontext->type;
1793 } else {
1794 /* Use the type of the related object. */
1795 newcontext.type = tcontext->type;
1796 }
1797 }
1798
1799 /* Look for a type transition/member/change rule. */
1800 avkey.source_type = scontext->type;
1801 avkey.target_type = tcontext->type;
1802 avkey.target_class = tclass;
1803 avkey.specified = specified;
1804 avdatum = avtab_search(&policydb->te_avtab, &avkey);
1805
1806 /* If no permanent rule, also check for enabled conditional rules */
1807 if (!avdatum) {
1808 node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1809 for (; node; node = avtab_search_node_next(node, specified)) {
1810 if (node->key.specified & AVTAB_ENABLED) {
1811 avdatum = &node->datum;
1812 break;
1813 }
1814 }
1815 }
1816
1817 if (avdatum) {
1818 /* Use the type from the type transition/member/change rule. */
1819 newcontext.type = avdatum->u.data;
1820 }
1821
1822 /* if we have a objname this is a file trans check so check those rules */
1823 if (objname)
1824 filename_compute_type(policydb, &newcontext, scontext->type,
1825 tcontext->type, tclass, objname);
1826
1827 /* Check for class-specific changes. */
1828 if (specified & AVTAB_TRANSITION) {
1829 /* Look for a role transition rule. */
1830 struct role_trans_datum *rtd;
1831 struct role_trans_key rtk = {
1832 .role = scontext->role,
1833 .type = tcontext->type,
1834 .tclass = tclass,
1835 };
1836
1837 rtd = policydb_roletr_search(policydb, &rtk);
1838 if (rtd)
1839 newcontext.role = rtd->new_role;
1840 }
1841
1842 /* Set the MLS attributes.
1843 This is done last because it may allocate memory. */
1844 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1845 &newcontext, sock);
1846 if (rc)
1847 goto out_unlock;
1848
1849 /* Check the validity of the context. */
1850 if (!policydb_context_isvalid(policydb, &newcontext)) {
1851 rc = compute_sid_handle_invalid_context(state, sentry, tentry,
1852 tclass, &newcontext);
1853 if (rc)
1854 goto out_unlock;
1855 }
1856 /* Obtain the sid for the context. */
1857 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1858out_unlock:
1859 read_unlock(&state->ss->policy_rwlock);
1860 context_destroy(&newcontext);
1861out:
1862 return rc;
1863}
1864
1865/**
1866 * security_transition_sid - Compute the SID for a new subject/object.
1867 * @ssid: source security identifier
1868 * @tsid: target security identifier
1869 * @tclass: target security class
1870 * @out_sid: security identifier for new subject/object
1871 *
1872 * Compute a SID to use for labeling a new subject or object in the
1873 * class @tclass based on a SID pair (@ssid, @tsid).
1874 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1875 * if insufficient memory is available, or %0 if the new SID was
1876 * computed successfully.
1877 */
1878int security_transition_sid(struct selinux_state *state,
1879 u32 ssid, u32 tsid, u16 tclass,
1880 const struct qstr *qstr, u32 *out_sid)
1881{
1882 return security_compute_sid(state, ssid, tsid, tclass,
1883 AVTAB_TRANSITION,
1884 qstr ? qstr->name : NULL, out_sid, true);
1885}
1886
1887int security_transition_sid_user(struct selinux_state *state,
1888 u32 ssid, u32 tsid, u16 tclass,
1889 const char *objname, u32 *out_sid)
1890{
1891 return security_compute_sid(state, ssid, tsid, tclass,
1892 AVTAB_TRANSITION,
1893 objname, out_sid, false);
1894}
1895
1896/**
1897 * security_member_sid - Compute the SID for member selection.
1898 * @ssid: source security identifier
1899 * @tsid: target security identifier
1900 * @tclass: target security class
1901 * @out_sid: security identifier for selected member
1902 *
1903 * Compute a SID to use when selecting a member of a polyinstantiated
1904 * object of class @tclass based on a SID pair (@ssid, @tsid).
1905 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1906 * if insufficient memory is available, or %0 if the SID was
1907 * computed successfully.
1908 */
1909int security_member_sid(struct selinux_state *state,
1910 u32 ssid,
1911 u32 tsid,
1912 u16 tclass,
1913 u32 *out_sid)
1914{
1915 return security_compute_sid(state, ssid, tsid, tclass,
1916 AVTAB_MEMBER, NULL,
1917 out_sid, false);
1918}
1919
1920/**
1921 * security_change_sid - Compute the SID for object relabeling.
1922 * @ssid: source security identifier
1923 * @tsid: target security identifier
1924 * @tclass: target security class
1925 * @out_sid: security identifier for selected member
1926 *
1927 * Compute a SID to use for relabeling an object of class @tclass
1928 * based on a SID pair (@ssid, @tsid).
1929 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1930 * if insufficient memory is available, or %0 if the SID was
1931 * computed successfully.
1932 */
1933int security_change_sid(struct selinux_state *state,
1934 u32 ssid,
1935 u32 tsid,
1936 u16 tclass,
1937 u32 *out_sid)
1938{
1939 return security_compute_sid(state,
1940 ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1941 out_sid, false);
1942}
1943
1944static inline int convert_context_handle_invalid_context(
1945 struct selinux_state *state,
1946 struct context *context)
1947{
1948 struct policydb *policydb = &state->ss->policydb;
1949 char *s;
1950 u32 len;
1951
1952 if (enforcing_enabled(state))
1953 return -EINVAL;
1954
1955 if (!context_struct_to_string(policydb, context, &s, &len)) {
1956 pr_warn("SELinux: Context %s would be invalid if enforcing\n",
1957 s);
1958 kfree(s);
1959 }
1960 return 0;
1961}
1962
1963struct convert_context_args {
1964 struct selinux_state *state;
1965 struct policydb *oldp;
1966 struct policydb *newp;
1967};
1968
1969/*
1970 * Convert the values in the security context
1971 * structure `oldc' from the values specified
1972 * in the policy `p->oldp' to the values specified
1973 * in the policy `p->newp', storing the new context
1974 * in `newc'. Verify that the context is valid
1975 * under the new policy.
1976 */
1977static int convert_context(struct context *oldc, struct context *newc, void *p)
1978{
1979 struct convert_context_args *args;
1980 struct ocontext *oc;
1981 struct role_datum *role;
1982 struct type_datum *typdatum;
1983 struct user_datum *usrdatum;
1984 char *s;
1985 u32 len;
1986 int rc;
1987
1988 args = p;
1989
1990 if (oldc->str) {
1991 s = kstrdup(oldc->str, GFP_KERNEL);
1992 if (!s)
1993 return -ENOMEM;
1994
1995 rc = string_to_context_struct(args->newp, NULL, s,
1996 newc, SECSID_NULL);
1997 if (rc == -EINVAL) {
1998 /*
1999 * Retain string representation for later mapping.
2000 *
2001 * IMPORTANT: We need to copy the contents of oldc->str
2002 * back into s again because string_to_context_struct()
2003 * may have garbled it.
2004 */
2005 memcpy(s, oldc->str, oldc->len);
2006 context_init(newc);
2007 newc->str = s;
2008 newc->len = oldc->len;
2009 return 0;
2010 }
2011 kfree(s);
2012 if (rc) {
2013 /* Other error condition, e.g. ENOMEM. */
2014 pr_err("SELinux: Unable to map context %s, rc = %d.\n",
2015 oldc->str, -rc);
2016 return rc;
2017 }
2018 pr_info("SELinux: Context %s became valid (mapped).\n",
2019 oldc->str);
2020 return 0;
2021 }
2022
2023 context_init(newc);
2024
2025 /* Convert the user. */
2026 rc = -EINVAL;
2027 usrdatum = symtab_search(&args->newp->p_users,
2028 sym_name(args->oldp,
2029 SYM_USERS, oldc->user - 1));
2030 if (!usrdatum)
2031 goto bad;
2032 newc->user = usrdatum->value;
2033
2034 /* Convert the role. */
2035 rc = -EINVAL;
2036 role = symtab_search(&args->newp->p_roles,
2037 sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
2038 if (!role)
2039 goto bad;
2040 newc->role = role->value;
2041
2042 /* Convert the type. */
2043 rc = -EINVAL;
2044 typdatum = symtab_search(&args->newp->p_types,
2045 sym_name(args->oldp,
2046 SYM_TYPES, oldc->type - 1));
2047 if (!typdatum)
2048 goto bad;
2049 newc->type = typdatum->value;
2050
2051 /* Convert the MLS fields if dealing with MLS policies */
2052 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2053 rc = mls_convert_context(args->oldp, args->newp, oldc, newc);
2054 if (rc)
2055 goto bad;
2056 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2057 /*
2058 * Switching between non-MLS and MLS policy:
2059 * ensure that the MLS fields of the context for all
2060 * existing entries in the sidtab are filled in with a
2061 * suitable default value, likely taken from one of the
2062 * initial SIDs.
2063 */
2064 oc = args->newp->ocontexts[OCON_ISID];
2065 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2066 oc = oc->next;
2067 rc = -EINVAL;
2068 if (!oc) {
2069 pr_err("SELinux: unable to look up"
2070 " the initial SIDs list\n");
2071 goto bad;
2072 }
2073 rc = mls_range_set(newc, &oc->context[0].range);
2074 if (rc)
2075 goto bad;
2076 }
2077
2078 /* Check the validity of the new context. */
2079 if (!policydb_context_isvalid(args->newp, newc)) {
2080 rc = convert_context_handle_invalid_context(args->state, oldc);
2081 if (rc)
2082 goto bad;
2083 }
2084
2085 return 0;
2086bad:
2087 /* Map old representation to string and save it. */
2088 rc = context_struct_to_string(args->oldp, oldc, &s, &len);
2089 if (rc)
2090 return rc;
2091 context_destroy(newc);
2092 newc->str = s;
2093 newc->len = len;
2094 pr_info("SELinux: Context %s became invalid (unmapped).\n",
2095 newc->str);
2096 return 0;
2097}
2098
2099static void security_load_policycaps(struct selinux_state *state)
2100{
2101 struct policydb *p = &state->ss->policydb;
2102 unsigned int i;
2103 struct ebitmap_node *node;
2104
2105 for (i = 0; i < ARRAY_SIZE(state->policycap); i++)
2106 state->policycap[i] = ebitmap_get_bit(&p->policycaps, i);
2107
2108 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2109 pr_info("SELinux: policy capability %s=%d\n",
2110 selinux_policycap_names[i],
2111 ebitmap_get_bit(&p->policycaps, i));
2112
2113 ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2114 if (i >= ARRAY_SIZE(selinux_policycap_names))
2115 pr_info("SELinux: unknown policy capability %u\n",
2116 i);
2117 }
2118}
2119
2120static int security_preserve_bools(struct selinux_state *state,
2121 struct policydb *newpolicydb);
2122
2123/**
2124 * security_load_policy - Load a security policy configuration.
2125 * @data: binary policy data
2126 * @len: length of data in bytes
2127 *
2128 * Load a new set of security policy configuration data,
2129 * validate it and convert the SID table as necessary.
2130 * This function will flush the access vector cache after
2131 * loading the new policy.
2132 */
2133int security_load_policy(struct selinux_state *state, void *data, size_t len)
2134{
2135 struct policydb *policydb;
2136 struct sidtab *oldsidtab, *newsidtab;
2137 struct policydb *oldpolicydb, *newpolicydb;
2138 struct selinux_mapping *oldmapping;
2139 struct selinux_map newmap;
2140 struct sidtab_convert_params convert_params;
2141 struct convert_context_args args;
2142 u32 seqno;
2143 int rc = 0;
2144 struct policy_file file = { data, len }, *fp = &file;
2145
2146 policydb = &state->ss->policydb;
2147
2148 newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL);
2149 if (!newsidtab)
2150 return -ENOMEM;
2151
2152 if (!selinux_initialized(state)) {
2153 rc = policydb_read(policydb, fp);
2154 if (rc) {
2155 kfree(newsidtab);
2156 return rc;
2157 }
2158
2159 policydb->len = len;
2160 rc = selinux_set_mapping(policydb, secclass_map,
2161 &state->ss->map);
2162 if (rc) {
2163 kfree(newsidtab);
2164 policydb_destroy(policydb);
2165 return rc;
2166 }
2167
2168 rc = policydb_load_isids(policydb, newsidtab);
2169 if (rc) {
2170 kfree(newsidtab);
2171 policydb_destroy(policydb);
2172 return rc;
2173 }
2174
2175 state->ss->sidtab = newsidtab;
2176 security_load_policycaps(state);
2177 selinux_mark_initialized(state);
2178 seqno = ++state->ss->latest_granting;
2179 selinux_complete_init();
2180 avc_ss_reset(state->avc, seqno);
2181 selnl_notify_policyload(seqno);
2182 selinux_status_update_policyload(state, seqno);
2183 selinux_netlbl_cache_invalidate();
2184 selinux_xfrm_notify_policyload();
2185 return 0;
2186 }
2187
2188 oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL);
2189 if (!oldpolicydb) {
2190 kfree(newsidtab);
2191 return -ENOMEM;
2192 }
2193 newpolicydb = oldpolicydb + 1;
2194
2195 rc = policydb_read(newpolicydb, fp);
2196 if (rc) {
2197 kfree(newsidtab);
2198 goto out;
2199 }
2200
2201 newpolicydb->len = len;
2202 /* If switching between different policy types, log MLS status */
2203 if (policydb->mls_enabled && !newpolicydb->mls_enabled)
2204 pr_info("SELinux: Disabling MLS support...\n");
2205 else if (!policydb->mls_enabled && newpolicydb->mls_enabled)
2206 pr_info("SELinux: Enabling MLS support...\n");
2207
2208 rc = policydb_load_isids(newpolicydb, newsidtab);
2209 if (rc) {
2210 pr_err("SELinux: unable to load the initial SIDs\n");
2211 policydb_destroy(newpolicydb);
2212 kfree(newsidtab);
2213 goto out;
2214 }
2215
2216 rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap);
2217 if (rc)
2218 goto err;
2219
2220 rc = security_preserve_bools(state, newpolicydb);
2221 if (rc) {
2222 pr_err("SELinux: unable to preserve booleans\n");
2223 goto err;
2224 }
2225
2226 oldsidtab = state->ss->sidtab;
2227
2228 /*
2229 * Convert the internal representations of contexts
2230 * in the new SID table.
2231 */
2232 args.state = state;
2233 args.oldp = policydb;
2234 args.newp = newpolicydb;
2235
2236 convert_params.func = convert_context;
2237 convert_params.args = &args;
2238 convert_params.target = newsidtab;
2239
2240 rc = sidtab_convert(oldsidtab, &convert_params);
2241 if (rc) {
2242 pr_err("SELinux: unable to convert the internal"
2243 " representation of contexts in the new SID"
2244 " table\n");
2245 goto err;
2246 }
2247
2248 /* Save the old policydb and SID table to free later. */
2249 memcpy(oldpolicydb, policydb, sizeof(*policydb));
2250
2251 /* Install the new policydb and SID table. */
2252 write_lock_irq(&state->ss->policy_rwlock);
2253 memcpy(policydb, newpolicydb, sizeof(*policydb));
2254 state->ss->sidtab = newsidtab;
2255 security_load_policycaps(state);
2256 oldmapping = state->ss->map.mapping;
2257 state->ss->map.mapping = newmap.mapping;
2258 state->ss->map.size = newmap.size;
2259 seqno = ++state->ss->latest_granting;
2260 write_unlock_irq(&state->ss->policy_rwlock);
2261
2262 /* Free the old policydb and SID table. */
2263 policydb_destroy(oldpolicydb);
2264 sidtab_destroy(oldsidtab);
2265 kfree(oldsidtab);
2266 kfree(oldmapping);
2267
2268 avc_ss_reset(state->avc, seqno);
2269 selnl_notify_policyload(seqno);
2270 selinux_status_update_policyload(state, seqno);
2271 selinux_netlbl_cache_invalidate();
2272 selinux_xfrm_notify_policyload();
2273
2274 rc = 0;
2275 goto out;
2276
2277err:
2278 kfree(newmap.mapping);
2279 sidtab_destroy(newsidtab);
2280 kfree(newsidtab);
2281 policydb_destroy(newpolicydb);
2282
2283out:
2284 kfree(oldpolicydb);
2285 return rc;
2286}
2287
2288size_t security_policydb_len(struct selinux_state *state)
2289{
2290 struct policydb *p = &state->ss->policydb;
2291 size_t len;
2292
2293 read_lock(&state->ss->policy_rwlock);
2294 len = p->len;
2295 read_unlock(&state->ss->policy_rwlock);
2296
2297 return len;
2298}
2299
2300/**
2301 * security_port_sid - Obtain the SID for a port.
2302 * @protocol: protocol number
2303 * @port: port number
2304 * @out_sid: security identifier
2305 */
2306int security_port_sid(struct selinux_state *state,
2307 u8 protocol, u16 port, u32 *out_sid)
2308{
2309 struct policydb *policydb;
2310 struct sidtab *sidtab;
2311 struct ocontext *c;
2312 int rc = 0;
2313
2314 read_lock(&state->ss->policy_rwlock);
2315
2316 policydb = &state->ss->policydb;
2317 sidtab = state->ss->sidtab;
2318
2319 c = policydb->ocontexts[OCON_PORT];
2320 while (c) {
2321 if (c->u.port.protocol == protocol &&
2322 c->u.port.low_port <= port &&
2323 c->u.port.high_port >= port)
2324 break;
2325 c = c->next;
2326 }
2327
2328 if (c) {
2329 if (!c->sid[0]) {
2330 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2331 &c->sid[0]);
2332 if (rc)
2333 goto out;
2334 }
2335 *out_sid = c->sid[0];
2336 } else {
2337 *out_sid = SECINITSID_PORT;
2338 }
2339
2340out:
2341 read_unlock(&state->ss->policy_rwlock);
2342 return rc;
2343}
2344
2345/**
2346 * security_pkey_sid - Obtain the SID for a pkey.
2347 * @subnet_prefix: Subnet Prefix
2348 * @pkey_num: pkey number
2349 * @out_sid: security identifier
2350 */
2351int security_ib_pkey_sid(struct selinux_state *state,
2352 u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2353{
2354 struct policydb *policydb;
2355 struct sidtab *sidtab;
2356 struct ocontext *c;
2357 int rc = 0;
2358
2359 read_lock(&state->ss->policy_rwlock);
2360
2361 policydb = &state->ss->policydb;
2362 sidtab = state->ss->sidtab;
2363
2364 c = policydb->ocontexts[OCON_IBPKEY];
2365 while (c) {
2366 if (c->u.ibpkey.low_pkey <= pkey_num &&
2367 c->u.ibpkey.high_pkey >= pkey_num &&
2368 c->u.ibpkey.subnet_prefix == subnet_prefix)
2369 break;
2370
2371 c = c->next;
2372 }
2373
2374 if (c) {
2375 if (!c->sid[0]) {
2376 rc = sidtab_context_to_sid(sidtab,
2377 &c->context[0],
2378 &c->sid[0]);
2379 if (rc)
2380 goto out;
2381 }
2382 *out_sid = c->sid[0];
2383 } else
2384 *out_sid = SECINITSID_UNLABELED;
2385
2386out:
2387 read_unlock(&state->ss->policy_rwlock);
2388 return rc;
2389}
2390
2391/**
2392 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2393 * @dev_name: device name
2394 * @port: port number
2395 * @out_sid: security identifier
2396 */
2397int security_ib_endport_sid(struct selinux_state *state,
2398 const char *dev_name, u8 port_num, u32 *out_sid)
2399{
2400 struct policydb *policydb;
2401 struct sidtab *sidtab;
2402 struct ocontext *c;
2403 int rc = 0;
2404
2405 read_lock(&state->ss->policy_rwlock);
2406
2407 policydb = &state->ss->policydb;
2408 sidtab = state->ss->sidtab;
2409
2410 c = policydb->ocontexts[OCON_IBENDPORT];
2411 while (c) {
2412 if (c->u.ibendport.port == port_num &&
2413 !strncmp(c->u.ibendport.dev_name,
2414 dev_name,
2415 IB_DEVICE_NAME_MAX))
2416 break;
2417
2418 c = c->next;
2419 }
2420
2421 if (c) {
2422 if (!c->sid[0]) {
2423 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2424 &c->sid[0]);
2425 if (rc)
2426 goto out;
2427 }
2428 *out_sid = c->sid[0];
2429 } else
2430 *out_sid = SECINITSID_UNLABELED;
2431
2432out:
2433 read_unlock(&state->ss->policy_rwlock);
2434 return rc;
2435}
2436
2437/**
2438 * security_netif_sid - Obtain the SID for a network interface.
2439 * @name: interface name
2440 * @if_sid: interface SID
2441 */
2442int security_netif_sid(struct selinux_state *state,
2443 char *name, u32 *if_sid)
2444{
2445 struct policydb *policydb;
2446 struct sidtab *sidtab;
2447 int rc = 0;
2448 struct ocontext *c;
2449
2450 read_lock(&state->ss->policy_rwlock);
2451
2452 policydb = &state->ss->policydb;
2453 sidtab = state->ss->sidtab;
2454
2455 c = policydb->ocontexts[OCON_NETIF];
2456 while (c) {
2457 if (strcmp(name, c->u.name) == 0)
2458 break;
2459 c = c->next;
2460 }
2461
2462 if (c) {
2463 if (!c->sid[0] || !c->sid[1]) {
2464 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2465 &c->sid[0]);
2466 if (rc)
2467 goto out;
2468 rc = sidtab_context_to_sid(sidtab, &c->context[1],
2469 &c->sid[1]);
2470 if (rc)
2471 goto out;
2472 }
2473 *if_sid = c->sid[0];
2474 } else
2475 *if_sid = SECINITSID_NETIF;
2476
2477out:
2478 read_unlock(&state->ss->policy_rwlock);
2479 return rc;
2480}
2481
2482static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2483{
2484 int i, fail = 0;
2485
2486 for (i = 0; i < 4; i++)
2487 if (addr[i] != (input[i] & mask[i])) {
2488 fail = 1;
2489 break;
2490 }
2491
2492 return !fail;
2493}
2494
2495/**
2496 * security_node_sid - Obtain the SID for a node (host).
2497 * @domain: communication domain aka address family
2498 * @addrp: address
2499 * @addrlen: address length in bytes
2500 * @out_sid: security identifier
2501 */
2502int security_node_sid(struct selinux_state *state,
2503 u16 domain,
2504 void *addrp,
2505 u32 addrlen,
2506 u32 *out_sid)
2507{
2508 struct policydb *policydb;
2509 struct sidtab *sidtab;
2510 int rc;
2511 struct ocontext *c;
2512
2513 read_lock(&state->ss->policy_rwlock);
2514
2515 policydb = &state->ss->policydb;
2516 sidtab = state->ss->sidtab;
2517
2518 switch (domain) {
2519 case AF_INET: {
2520 u32 addr;
2521
2522 rc = -EINVAL;
2523 if (addrlen != sizeof(u32))
2524 goto out;
2525
2526 addr = *((u32 *)addrp);
2527
2528 c = policydb->ocontexts[OCON_NODE];
2529 while (c) {
2530 if (c->u.node.addr == (addr & c->u.node.mask))
2531 break;
2532 c = c->next;
2533 }
2534 break;
2535 }
2536
2537 case AF_INET6:
2538 rc = -EINVAL;
2539 if (addrlen != sizeof(u64) * 2)
2540 goto out;
2541 c = policydb->ocontexts[OCON_NODE6];
2542 while (c) {
2543 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2544 c->u.node6.mask))
2545 break;
2546 c = c->next;
2547 }
2548 break;
2549
2550 default:
2551 rc = 0;
2552 *out_sid = SECINITSID_NODE;
2553 goto out;
2554 }
2555
2556 if (c) {
2557 if (!c->sid[0]) {
2558 rc = sidtab_context_to_sid(sidtab,
2559 &c->context[0],
2560 &c->sid[0]);
2561 if (rc)
2562 goto out;
2563 }
2564 *out_sid = c->sid[0];
2565 } else {
2566 *out_sid = SECINITSID_NODE;
2567 }
2568
2569 rc = 0;
2570out:
2571 read_unlock(&state->ss->policy_rwlock);
2572 return rc;
2573}
2574
2575#define SIDS_NEL 25
2576
2577/**
2578 * security_get_user_sids - Obtain reachable SIDs for a user.
2579 * @fromsid: starting SID
2580 * @username: username
2581 * @sids: array of reachable SIDs for user
2582 * @nel: number of elements in @sids
2583 *
2584 * Generate the set of SIDs for legal security contexts
2585 * for a given user that can be reached by @fromsid.
2586 * Set *@sids to point to a dynamically allocated
2587 * array containing the set of SIDs. Set *@nel to the
2588 * number of elements in the array.
2589 */
2590
2591int security_get_user_sids(struct selinux_state *state,
2592 u32 fromsid,
2593 char *username,
2594 u32 **sids,
2595 u32 *nel)
2596{
2597 struct policydb *policydb;
2598 struct sidtab *sidtab;
2599 struct context *fromcon, usercon;
2600 u32 *mysids = NULL, *mysids2, sid;
2601 u32 mynel = 0, maxnel = SIDS_NEL;
2602 struct user_datum *user;
2603 struct role_datum *role;
2604 struct ebitmap_node *rnode, *tnode;
2605 int rc = 0, i, j;
2606
2607 *sids = NULL;
2608 *nel = 0;
2609
2610 if (!selinux_initialized(state))
2611 goto out;
2612
2613 read_lock(&state->ss->policy_rwlock);
2614
2615 policydb = &state->ss->policydb;
2616 sidtab = state->ss->sidtab;
2617
2618 context_init(&usercon);
2619
2620 rc = -EINVAL;
2621 fromcon = sidtab_search(sidtab, fromsid);
2622 if (!fromcon)
2623 goto out_unlock;
2624
2625 rc = -EINVAL;
2626 user = symtab_search(&policydb->p_users, username);
2627 if (!user)
2628 goto out_unlock;
2629
2630 usercon.user = user->value;
2631
2632 rc = -ENOMEM;
2633 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2634 if (!mysids)
2635 goto out_unlock;
2636
2637 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2638 role = policydb->role_val_to_struct[i];
2639 usercon.role = i + 1;
2640 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2641 usercon.type = j + 1;
2642
2643 if (mls_setup_user_range(policydb, fromcon, user,
2644 &usercon))
2645 continue;
2646
2647 rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2648 if (rc)
2649 goto out_unlock;
2650 if (mynel < maxnel) {
2651 mysids[mynel++] = sid;
2652 } else {
2653 rc = -ENOMEM;
2654 maxnel += SIDS_NEL;
2655 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2656 if (!mysids2)
2657 goto out_unlock;
2658 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2659 kfree(mysids);
2660 mysids = mysids2;
2661 mysids[mynel++] = sid;
2662 }
2663 }
2664 }
2665 rc = 0;
2666out_unlock:
2667 read_unlock(&state->ss->policy_rwlock);
2668 if (rc || !mynel) {
2669 kfree(mysids);
2670 goto out;
2671 }
2672
2673 rc = -ENOMEM;
2674 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2675 if (!mysids2) {
2676 kfree(mysids);
2677 goto out;
2678 }
2679 for (i = 0, j = 0; i < mynel; i++) {
2680 struct av_decision dummy_avd;
2681 rc = avc_has_perm_noaudit(state,
2682 fromsid, mysids[i],
2683 SECCLASS_PROCESS, /* kernel value */
2684 PROCESS__TRANSITION, AVC_STRICT,
2685 &dummy_avd);
2686 if (!rc)
2687 mysids2[j++] = mysids[i];
2688 cond_resched();
2689 }
2690 rc = 0;
2691 kfree(mysids);
2692 *sids = mysids2;
2693 *nel = j;
2694out:
2695 return rc;
2696}
2697
2698/**
2699 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2700 * @fstype: filesystem type
2701 * @path: path from root of mount
2702 * @sclass: file security class
2703 * @sid: SID for path
2704 *
2705 * Obtain a SID to use for a file in a filesystem that
2706 * cannot support xattr or use a fixed labeling behavior like
2707 * transition SIDs or task SIDs.
2708 *
2709 * The caller must acquire the policy_rwlock before calling this function.
2710 */
2711static inline int __security_genfs_sid(struct selinux_state *state,
2712 const char *fstype,
2713 char *path,
2714 u16 orig_sclass,
2715 u32 *sid)
2716{
2717 struct policydb *policydb = &state->ss->policydb;
2718 struct sidtab *sidtab = state->ss->sidtab;
2719 int len;
2720 u16 sclass;
2721 struct genfs *genfs;
2722 struct ocontext *c;
2723 int rc, cmp = 0;
2724
2725 while (path[0] == '/' && path[1] == '/')
2726 path++;
2727
2728 sclass = unmap_class(&state->ss->map, orig_sclass);
2729 *sid = SECINITSID_UNLABELED;
2730
2731 for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2732 cmp = strcmp(fstype, genfs->fstype);
2733 if (cmp <= 0)
2734 break;
2735 }
2736
2737 rc = -ENOENT;
2738 if (!genfs || cmp)
2739 goto out;
2740
2741 for (c = genfs->head; c; c = c->next) {
2742 len = strlen(c->u.name);
2743 if ((!c->v.sclass || sclass == c->v.sclass) &&
2744 (strncmp(c->u.name, path, len) == 0))
2745 break;
2746 }
2747
2748 rc = -ENOENT;
2749 if (!c)
2750 goto out;
2751
2752 if (!c->sid[0]) {
2753 rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]);
2754 if (rc)
2755 goto out;
2756 }
2757
2758 *sid = c->sid[0];
2759 rc = 0;
2760out:
2761 return rc;
2762}
2763
2764/**
2765 * security_genfs_sid - Obtain a SID for a file in a filesystem
2766 * @fstype: filesystem type
2767 * @path: path from root of mount
2768 * @sclass: file security class
2769 * @sid: SID for path
2770 *
2771 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2772 * it afterward.
2773 */
2774int security_genfs_sid(struct selinux_state *state,
2775 const char *fstype,
2776 char *path,
2777 u16 orig_sclass,
2778 u32 *sid)
2779{
2780 int retval;
2781
2782 read_lock(&state->ss->policy_rwlock);
2783 retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid);
2784 read_unlock(&state->ss->policy_rwlock);
2785 return retval;
2786}
2787
2788/**
2789 * security_fs_use - Determine how to handle labeling for a filesystem.
2790 * @sb: superblock in question
2791 */
2792int security_fs_use(struct selinux_state *state, struct super_block *sb)
2793{
2794 struct policydb *policydb;
2795 struct sidtab *sidtab;
2796 int rc = 0;
2797 struct ocontext *c;
2798 struct superblock_security_struct *sbsec = sb->s_security;
2799 const char *fstype = sb->s_type->name;
2800
2801 read_lock(&state->ss->policy_rwlock);
2802
2803 policydb = &state->ss->policydb;
2804 sidtab = state->ss->sidtab;
2805
2806 c = policydb->ocontexts[OCON_FSUSE];
2807 while (c) {
2808 if (strcmp(fstype, c->u.name) == 0)
2809 break;
2810 c = c->next;
2811 }
2812
2813 if (c) {
2814 sbsec->behavior = c->v.behavior;
2815 if (!c->sid[0]) {
2816 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2817 &c->sid[0]);
2818 if (rc)
2819 goto out;
2820 }
2821 sbsec->sid = c->sid[0];
2822 } else {
2823 rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR,
2824 &sbsec->sid);
2825 if (rc) {
2826 sbsec->behavior = SECURITY_FS_USE_NONE;
2827 rc = 0;
2828 } else {
2829 sbsec->behavior = SECURITY_FS_USE_GENFS;
2830 }
2831 }
2832
2833out:
2834 read_unlock(&state->ss->policy_rwlock);
2835 return rc;
2836}
2837
2838int security_get_bools(struct selinux_state *state,
2839 u32 *len, char ***names, int **values)
2840{
2841 struct policydb *policydb;
2842 u32 i;
2843 int rc;
2844
2845 if (!selinux_initialized(state)) {
2846 *len = 0;
2847 *names = NULL;
2848 *values = NULL;
2849 return 0;
2850 }
2851
2852 read_lock(&state->ss->policy_rwlock);
2853
2854 policydb = &state->ss->policydb;
2855
2856 *names = NULL;
2857 *values = NULL;
2858
2859 rc = 0;
2860 *len = policydb->p_bools.nprim;
2861 if (!*len)
2862 goto out;
2863
2864 rc = -ENOMEM;
2865 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2866 if (!*names)
2867 goto err;
2868
2869 rc = -ENOMEM;
2870 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2871 if (!*values)
2872 goto err;
2873
2874 for (i = 0; i < *len; i++) {
2875 (*values)[i] = policydb->bool_val_to_struct[i]->state;
2876
2877 rc = -ENOMEM;
2878 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
2879 GFP_ATOMIC);
2880 if (!(*names)[i])
2881 goto err;
2882 }
2883 rc = 0;
2884out:
2885 read_unlock(&state->ss->policy_rwlock);
2886 return rc;
2887err:
2888 if (*names) {
2889 for (i = 0; i < *len; i++)
2890 kfree((*names)[i]);
2891 kfree(*names);
2892 }
2893 kfree(*values);
2894 *len = 0;
2895 *names = NULL;
2896 *values = NULL;
2897 goto out;
2898}
2899
2900
2901int security_set_bools(struct selinux_state *state, u32 len, int *values)
2902{
2903 struct policydb *policydb;
2904 int rc;
2905 u32 i, lenp, seqno = 0;
2906
2907 write_lock_irq(&state->ss->policy_rwlock);
2908
2909 policydb = &state->ss->policydb;
2910
2911 rc = -EFAULT;
2912 lenp = policydb->p_bools.nprim;
2913 if (len != lenp)
2914 goto out;
2915
2916 for (i = 0; i < len; i++) {
2917 if (!!values[i] != policydb->bool_val_to_struct[i]->state) {
2918 audit_log(audit_context(), GFP_ATOMIC,
2919 AUDIT_MAC_CONFIG_CHANGE,
2920 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2921 sym_name(policydb, SYM_BOOLS, i),
2922 !!values[i],
2923 policydb->bool_val_to_struct[i]->state,
2924 from_kuid(&init_user_ns, audit_get_loginuid(current)),
2925 audit_get_sessionid(current));
2926 }
2927 if (values[i])
2928 policydb->bool_val_to_struct[i]->state = 1;
2929 else
2930 policydb->bool_val_to_struct[i]->state = 0;
2931 }
2932
2933 evaluate_cond_nodes(policydb);
2934
2935 seqno = ++state->ss->latest_granting;
2936 rc = 0;
2937out:
2938 write_unlock_irq(&state->ss->policy_rwlock);
2939 if (!rc) {
2940 avc_ss_reset(state->avc, seqno);
2941 selnl_notify_policyload(seqno);
2942 selinux_status_update_policyload(state, seqno);
2943 selinux_xfrm_notify_policyload();
2944 }
2945 return rc;
2946}
2947
2948int security_get_bool_value(struct selinux_state *state,
2949 u32 index)
2950{
2951 struct policydb *policydb;
2952 int rc;
2953 u32 len;
2954
2955 read_lock(&state->ss->policy_rwlock);
2956
2957 policydb = &state->ss->policydb;
2958
2959 rc = -EFAULT;
2960 len = policydb->p_bools.nprim;
2961 if (index >= len)
2962 goto out;
2963
2964 rc = policydb->bool_val_to_struct[index]->state;
2965out:
2966 read_unlock(&state->ss->policy_rwlock);
2967 return rc;
2968}
2969
2970static int security_preserve_bools(struct selinux_state *state,
2971 struct policydb *policydb)
2972{
2973 int rc, *bvalues = NULL;
2974 char **bnames = NULL;
2975 struct cond_bool_datum *booldatum;
2976 u32 i, nbools = 0;
2977
2978 rc = security_get_bools(state, &nbools, &bnames, &bvalues);
2979 if (rc)
2980 goto out;
2981 for (i = 0; i < nbools; i++) {
2982 booldatum = symtab_search(&policydb->p_bools, bnames[i]);
2983 if (booldatum)
2984 booldatum->state = bvalues[i];
2985 }
2986 evaluate_cond_nodes(policydb);
2987
2988out:
2989 if (bnames) {
2990 for (i = 0; i < nbools; i++)
2991 kfree(bnames[i]);
2992 }
2993 kfree(bnames);
2994 kfree(bvalues);
2995 return rc;
2996}
2997
2998/*
2999 * security_sid_mls_copy() - computes a new sid based on the given
3000 * sid and the mls portion of mls_sid.
3001 */
3002int security_sid_mls_copy(struct selinux_state *state,
3003 u32 sid, u32 mls_sid, u32 *new_sid)
3004{
3005 struct policydb *policydb = &state->ss->policydb;
3006 struct sidtab *sidtab = state->ss->sidtab;
3007 struct context *context1;
3008 struct context *context2;
3009 struct context newcon;
3010 char *s;
3011 u32 len;
3012 int rc;
3013
3014 rc = 0;
3015 if (!selinux_initialized(state) || !policydb->mls_enabled) {
3016 *new_sid = sid;
3017 goto out;
3018 }
3019
3020 context_init(&newcon);
3021
3022 read_lock(&state->ss->policy_rwlock);
3023
3024 rc = -EINVAL;
3025 context1 = sidtab_search(sidtab, sid);
3026 if (!context1) {
3027 pr_err("SELinux: %s: unrecognized SID %d\n",
3028 __func__, sid);
3029 goto out_unlock;
3030 }
3031
3032 rc = -EINVAL;
3033 context2 = sidtab_search(sidtab, mls_sid);
3034 if (!context2) {
3035 pr_err("SELinux: %s: unrecognized SID %d\n",
3036 __func__, mls_sid);
3037 goto out_unlock;
3038 }
3039
3040 newcon.user = context1->user;
3041 newcon.role = context1->role;
3042 newcon.type = context1->type;
3043 rc = mls_context_cpy(&newcon, context2);
3044 if (rc)
3045 goto out_unlock;
3046
3047 /* Check the validity of the new context. */
3048 if (!policydb_context_isvalid(policydb, &newcon)) {
3049 rc = convert_context_handle_invalid_context(state, &newcon);
3050 if (rc) {
3051 if (!context_struct_to_string(policydb, &newcon, &s,
3052 &len)) {
3053 struct audit_buffer *ab;
3054
3055 ab = audit_log_start(audit_context(),
3056 GFP_ATOMIC,
3057 AUDIT_SELINUX_ERR);
3058 audit_log_format(ab,
3059 "op=security_sid_mls_copy invalid_context=");
3060 /* don't record NUL with untrusted strings */
3061 audit_log_n_untrustedstring(ab, s, len - 1);
3062 audit_log_end(ab);
3063 kfree(s);
3064 }
3065 goto out_unlock;
3066 }
3067 }
3068 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3069out_unlock:
3070 read_unlock(&state->ss->policy_rwlock);
3071 context_destroy(&newcon);
3072out:
3073 return rc;
3074}
3075
3076/**
3077 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3078 * @nlbl_sid: NetLabel SID
3079 * @nlbl_type: NetLabel labeling protocol type
3080 * @xfrm_sid: XFRM SID
3081 *
3082 * Description:
3083 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3084 * resolved into a single SID it is returned via @peer_sid and the function
3085 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3086 * returns a negative value. A table summarizing the behavior is below:
3087 *
3088 * | function return | @sid
3089 * ------------------------------+-----------------+-----------------
3090 * no peer labels | 0 | SECSID_NULL
3091 * single peer label | 0 | <peer_label>
3092 * multiple, consistent labels | 0 | <peer_label>
3093 * multiple, inconsistent labels | -<errno> | SECSID_NULL
3094 *
3095 */
3096int security_net_peersid_resolve(struct selinux_state *state,
3097 u32 nlbl_sid, u32 nlbl_type,
3098 u32 xfrm_sid,
3099 u32 *peer_sid)
3100{
3101 struct policydb *policydb = &state->ss->policydb;
3102 struct sidtab *sidtab = state->ss->sidtab;
3103 int rc;
3104 struct context *nlbl_ctx;
3105 struct context *xfrm_ctx;
3106
3107 *peer_sid = SECSID_NULL;
3108
3109 /* handle the common (which also happens to be the set of easy) cases
3110 * right away, these two if statements catch everything involving a
3111 * single or absent peer SID/label */
3112 if (xfrm_sid == SECSID_NULL) {
3113 *peer_sid = nlbl_sid;
3114 return 0;
3115 }
3116 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3117 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3118 * is present */
3119 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3120 *peer_sid = xfrm_sid;
3121 return 0;
3122 }
3123
3124 /*
3125 * We don't need to check initialized here since the only way both
3126 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3127 * security server was initialized and state->initialized was true.
3128 */
3129 if (!policydb->mls_enabled)
3130 return 0;
3131
3132 read_lock(&state->ss->policy_rwlock);
3133
3134 rc = -EINVAL;
3135 nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3136 if (!nlbl_ctx) {
3137 pr_err("SELinux: %s: unrecognized SID %d\n",
3138 __func__, nlbl_sid);
3139 goto out;
3140 }
3141 rc = -EINVAL;
3142 xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3143 if (!xfrm_ctx) {
3144 pr_err("SELinux: %s: unrecognized SID %d\n",
3145 __func__, xfrm_sid);
3146 goto out;
3147 }
3148 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3149 if (rc)
3150 goto out;
3151
3152 /* at present NetLabel SIDs/labels really only carry MLS
3153 * information so if the MLS portion of the NetLabel SID
3154 * matches the MLS portion of the labeled XFRM SID/label
3155 * then pass along the XFRM SID as it is the most
3156 * expressive */
3157 *peer_sid = xfrm_sid;
3158out:
3159 read_unlock(&state->ss->policy_rwlock);
3160 return rc;
3161}
3162
3163static int get_classes_callback(void *k, void *d, void *args)
3164{
3165 struct class_datum *datum = d;
3166 char *name = k, **classes = args;
3167 int value = datum->value - 1;
3168
3169 classes[value] = kstrdup(name, GFP_ATOMIC);
3170 if (!classes[value])
3171 return -ENOMEM;
3172
3173 return 0;
3174}
3175
3176int security_get_classes(struct selinux_state *state,
3177 char ***classes, int *nclasses)
3178{
3179 struct policydb *policydb = &state->ss->policydb;
3180 int rc;
3181
3182 if (!selinux_initialized(state)) {
3183 *nclasses = 0;
3184 *classes = NULL;
3185 return 0;
3186 }
3187
3188 read_lock(&state->ss->policy_rwlock);
3189
3190 rc = -ENOMEM;
3191 *nclasses = policydb->p_classes.nprim;
3192 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3193 if (!*classes)
3194 goto out;
3195
3196 rc = hashtab_map(&policydb->p_classes.table, get_classes_callback,
3197 *classes);
3198 if (rc) {
3199 int i;
3200 for (i = 0; i < *nclasses; i++)
3201 kfree((*classes)[i]);
3202 kfree(*classes);
3203 }
3204
3205out:
3206 read_unlock(&state->ss->policy_rwlock);
3207 return rc;
3208}
3209
3210static int get_permissions_callback(void *k, void *d, void *args)
3211{
3212 struct perm_datum *datum = d;
3213 char *name = k, **perms = args;
3214 int value = datum->value - 1;
3215
3216 perms[value] = kstrdup(name, GFP_ATOMIC);
3217 if (!perms[value])
3218 return -ENOMEM;
3219
3220 return 0;
3221}
3222
3223int security_get_permissions(struct selinux_state *state,
3224 char *class, char ***perms, int *nperms)
3225{
3226 struct policydb *policydb = &state->ss->policydb;
3227 int rc, i;
3228 struct class_datum *match;
3229
3230 read_lock(&state->ss->policy_rwlock);
3231
3232 rc = -EINVAL;
3233 match = symtab_search(&policydb->p_classes, class);
3234 if (!match) {
3235 pr_err("SELinux: %s: unrecognized class %s\n",
3236 __func__, class);
3237 goto out;
3238 }
3239
3240 rc = -ENOMEM;
3241 *nperms = match->permissions.nprim;
3242 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3243 if (!*perms)
3244 goto out;
3245
3246 if (match->comdatum) {
3247 rc = hashtab_map(&match->comdatum->permissions.table,
3248 get_permissions_callback, *perms);
3249 if (rc)
3250 goto err;
3251 }
3252
3253 rc = hashtab_map(&match->permissions.table, get_permissions_callback,
3254 *perms);
3255 if (rc)
3256 goto err;
3257
3258out:
3259 read_unlock(&state->ss->policy_rwlock);
3260 return rc;
3261
3262err:
3263 read_unlock(&state->ss->policy_rwlock);
3264 for (i = 0; i < *nperms; i++)
3265 kfree((*perms)[i]);
3266 kfree(*perms);
3267 return rc;
3268}
3269
3270int security_get_reject_unknown(struct selinux_state *state)
3271{
3272 return state->ss->policydb.reject_unknown;
3273}
3274
3275int security_get_allow_unknown(struct selinux_state *state)
3276{
3277 return state->ss->policydb.allow_unknown;
3278}
3279
3280/**
3281 * security_policycap_supported - Check for a specific policy capability
3282 * @req_cap: capability
3283 *
3284 * Description:
3285 * This function queries the currently loaded policy to see if it supports the
3286 * capability specified by @req_cap. Returns true (1) if the capability is
3287 * supported, false (0) if it isn't supported.
3288 *
3289 */
3290int security_policycap_supported(struct selinux_state *state,
3291 unsigned int req_cap)
3292{
3293 struct policydb *policydb = &state->ss->policydb;
3294 int rc;
3295
3296 read_lock(&state->ss->policy_rwlock);
3297 rc = ebitmap_get_bit(&policydb->policycaps, req_cap);
3298 read_unlock(&state->ss->policy_rwlock);
3299
3300 return rc;
3301}
3302
3303struct selinux_audit_rule {
3304 u32 au_seqno;
3305 struct context au_ctxt;
3306};
3307
3308void selinux_audit_rule_free(void *vrule)
3309{
3310 struct selinux_audit_rule *rule = vrule;
3311
3312 if (rule) {
3313 context_destroy(&rule->au_ctxt);
3314 kfree(rule);
3315 }
3316}
3317
3318int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3319{
3320 struct selinux_state *state = &selinux_state;
3321 struct policydb *policydb = &state->ss->policydb;
3322 struct selinux_audit_rule *tmprule;
3323 struct role_datum *roledatum;
3324 struct type_datum *typedatum;
3325 struct user_datum *userdatum;
3326 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3327 int rc = 0;
3328
3329 *rule = NULL;
3330
3331 if (!selinux_initialized(state))
3332 return -EOPNOTSUPP;
3333
3334 switch (field) {
3335 case AUDIT_SUBJ_USER:
3336 case AUDIT_SUBJ_ROLE:
3337 case AUDIT_SUBJ_TYPE:
3338 case AUDIT_OBJ_USER:
3339 case AUDIT_OBJ_ROLE:
3340 case AUDIT_OBJ_TYPE:
3341 /* only 'equals' and 'not equals' fit user, role, and type */
3342 if (op != Audit_equal && op != Audit_not_equal)
3343 return -EINVAL;
3344 break;
3345 case AUDIT_SUBJ_SEN:
3346 case AUDIT_SUBJ_CLR:
3347 case AUDIT_OBJ_LEV_LOW:
3348 case AUDIT_OBJ_LEV_HIGH:
3349 /* we do not allow a range, indicated by the presence of '-' */
3350 if (strchr(rulestr, '-'))
3351 return -EINVAL;
3352 break;
3353 default:
3354 /* only the above fields are valid */
3355 return -EINVAL;
3356 }
3357
3358 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3359 if (!tmprule)
3360 return -ENOMEM;
3361
3362 context_init(&tmprule->au_ctxt);
3363
3364 read_lock(&state->ss->policy_rwlock);
3365
3366 tmprule->au_seqno = state->ss->latest_granting;
3367
3368 switch (field) {
3369 case AUDIT_SUBJ_USER:
3370 case AUDIT_OBJ_USER:
3371 rc = -EINVAL;
3372 userdatum = symtab_search(&policydb->p_users, rulestr);
3373 if (!userdatum)
3374 goto out;
3375 tmprule->au_ctxt.user = userdatum->value;
3376 break;
3377 case AUDIT_SUBJ_ROLE:
3378 case AUDIT_OBJ_ROLE:
3379 rc = -EINVAL;
3380 roledatum = symtab_search(&policydb->p_roles, rulestr);
3381 if (!roledatum)
3382 goto out;
3383 tmprule->au_ctxt.role = roledatum->value;
3384 break;
3385 case AUDIT_SUBJ_TYPE:
3386 case AUDIT_OBJ_TYPE:
3387 rc = -EINVAL;
3388 typedatum = symtab_search(&policydb->p_types, rulestr);
3389 if (!typedatum)
3390 goto out;
3391 tmprule->au_ctxt.type = typedatum->value;
3392 break;
3393 case AUDIT_SUBJ_SEN:
3394 case AUDIT_SUBJ_CLR:
3395 case AUDIT_OBJ_LEV_LOW:
3396 case AUDIT_OBJ_LEV_HIGH:
3397 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3398 GFP_ATOMIC);
3399 if (rc)
3400 goto out;
3401 break;
3402 }
3403 rc = 0;
3404out:
3405 read_unlock(&state->ss->policy_rwlock);
3406
3407 if (rc) {
3408 selinux_audit_rule_free(tmprule);
3409 tmprule = NULL;
3410 }
3411
3412 *rule = tmprule;
3413
3414 return rc;
3415}
3416
3417/* Check to see if the rule contains any selinux fields */
3418int selinux_audit_rule_known(struct audit_krule *rule)
3419{
3420 int i;
3421
3422 for (i = 0; i < rule->field_count; i++) {
3423 struct audit_field *f = &rule->fields[i];
3424 switch (f->type) {
3425 case AUDIT_SUBJ_USER:
3426 case AUDIT_SUBJ_ROLE:
3427 case AUDIT_SUBJ_TYPE:
3428 case AUDIT_SUBJ_SEN:
3429 case AUDIT_SUBJ_CLR:
3430 case AUDIT_OBJ_USER:
3431 case AUDIT_OBJ_ROLE:
3432 case AUDIT_OBJ_TYPE:
3433 case AUDIT_OBJ_LEV_LOW:
3434 case AUDIT_OBJ_LEV_HIGH:
3435 return 1;
3436 }
3437 }
3438
3439 return 0;
3440}
3441
3442int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule)
3443{
3444 struct selinux_state *state = &selinux_state;
3445 struct context *ctxt;
3446 struct mls_level *level;
3447 struct selinux_audit_rule *rule = vrule;
3448 int match = 0;
3449
3450 if (unlikely(!rule)) {
3451 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3452 return -ENOENT;
3453 }
3454
3455 read_lock(&state->ss->policy_rwlock);
3456
3457 if (rule->au_seqno < state->ss->latest_granting) {
3458 match = -ESTALE;
3459 goto out;
3460 }
3461
3462 ctxt = sidtab_search(state->ss->sidtab, sid);
3463 if (unlikely(!ctxt)) {
3464 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3465 sid);
3466 match = -ENOENT;
3467 goto out;
3468 }
3469
3470 /* a field/op pair that is not caught here will simply fall through
3471 without a match */
3472 switch (field) {
3473 case AUDIT_SUBJ_USER:
3474 case AUDIT_OBJ_USER:
3475 switch (op) {
3476 case Audit_equal:
3477 match = (ctxt->user == rule->au_ctxt.user);
3478 break;
3479 case Audit_not_equal:
3480 match = (ctxt->user != rule->au_ctxt.user);
3481 break;
3482 }
3483 break;
3484 case AUDIT_SUBJ_ROLE:
3485 case AUDIT_OBJ_ROLE:
3486 switch (op) {
3487 case Audit_equal:
3488 match = (ctxt->role == rule->au_ctxt.role);
3489 break;
3490 case Audit_not_equal:
3491 match = (ctxt->role != rule->au_ctxt.role);
3492 break;
3493 }
3494 break;
3495 case AUDIT_SUBJ_TYPE:
3496 case AUDIT_OBJ_TYPE:
3497 switch (op) {
3498 case Audit_equal:
3499 match = (ctxt->type == rule->au_ctxt.type);
3500 break;
3501 case Audit_not_equal:
3502 match = (ctxt->type != rule->au_ctxt.type);
3503 break;
3504 }
3505 break;
3506 case AUDIT_SUBJ_SEN:
3507 case AUDIT_SUBJ_CLR:
3508 case AUDIT_OBJ_LEV_LOW:
3509 case AUDIT_OBJ_LEV_HIGH:
3510 level = ((field == AUDIT_SUBJ_SEN ||
3511 field == AUDIT_OBJ_LEV_LOW) ?
3512 &ctxt->range.level[0] : &ctxt->range.level[1]);
3513 switch (op) {
3514 case Audit_equal:
3515 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3516 level);
3517 break;
3518 case Audit_not_equal:
3519 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3520 level);
3521 break;
3522 case Audit_lt:
3523 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3524 level) &&
3525 !mls_level_eq(&rule->au_ctxt.range.level[0],
3526 level));
3527 break;
3528 case Audit_le:
3529 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3530 level);
3531 break;
3532 case Audit_gt:
3533 match = (mls_level_dom(level,
3534 &rule->au_ctxt.range.level[0]) &&
3535 !mls_level_eq(level,
3536 &rule->au_ctxt.range.level[0]));
3537 break;
3538 case Audit_ge:
3539 match = mls_level_dom(level,
3540 &rule->au_ctxt.range.level[0]);
3541 break;
3542 }
3543 }
3544
3545out:
3546 read_unlock(&state->ss->policy_rwlock);
3547 return match;
3548}
3549
3550static int (*aurule_callback)(void) = audit_update_lsm_rules;
3551
3552static int aurule_avc_callback(u32 event)
3553{
3554 int err = 0;
3555
3556 if (event == AVC_CALLBACK_RESET && aurule_callback)
3557 err = aurule_callback();
3558 return err;
3559}
3560
3561static int __init aurule_init(void)
3562{
3563 int err;
3564
3565 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3566 if (err)
3567 panic("avc_add_callback() failed, error %d\n", err);
3568
3569 return err;
3570}
3571__initcall(aurule_init);
3572
3573#ifdef CONFIG_NETLABEL
3574/**
3575 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3576 * @secattr: the NetLabel packet security attributes
3577 * @sid: the SELinux SID
3578 *
3579 * Description:
3580 * Attempt to cache the context in @ctx, which was derived from the packet in
3581 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3582 * already been initialized.
3583 *
3584 */
3585static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3586 u32 sid)
3587{
3588 u32 *sid_cache;
3589
3590 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3591 if (sid_cache == NULL)
3592 return;
3593 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3594 if (secattr->cache == NULL) {
3595 kfree(sid_cache);
3596 return;
3597 }
3598
3599 *sid_cache = sid;
3600 secattr->cache->free = kfree;
3601 secattr->cache->data = sid_cache;
3602 secattr->flags |= NETLBL_SECATTR_CACHE;
3603}
3604
3605/**
3606 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3607 * @secattr: the NetLabel packet security attributes
3608 * @sid: the SELinux SID
3609 *
3610 * Description:
3611 * Convert the given NetLabel security attributes in @secattr into a
3612 * SELinux SID. If the @secattr field does not contain a full SELinux
3613 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3614 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3615 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3616 * conversion for future lookups. Returns zero on success, negative values on
3617 * failure.
3618 *
3619 */
3620int security_netlbl_secattr_to_sid(struct selinux_state *state,
3621 struct netlbl_lsm_secattr *secattr,
3622 u32 *sid)
3623{
3624 struct policydb *policydb = &state->ss->policydb;
3625 struct sidtab *sidtab = state->ss->sidtab;
3626 int rc;
3627 struct context *ctx;
3628 struct context ctx_new;
3629
3630 if (!selinux_initialized(state)) {
3631 *sid = SECSID_NULL;
3632 return 0;
3633 }
3634
3635 read_lock(&state->ss->policy_rwlock);
3636
3637 if (secattr->flags & NETLBL_SECATTR_CACHE)
3638 *sid = *(u32 *)secattr->cache->data;
3639 else if (secattr->flags & NETLBL_SECATTR_SECID)
3640 *sid = secattr->attr.secid;
3641 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3642 rc = -EIDRM;
3643 ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3644 if (ctx == NULL)
3645 goto out;
3646
3647 context_init(&ctx_new);
3648 ctx_new.user = ctx->user;
3649 ctx_new.role = ctx->role;
3650 ctx_new.type = ctx->type;
3651 mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3652 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3653 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3654 if (rc)
3655 goto out;
3656 }
3657 rc = -EIDRM;
3658 if (!mls_context_isvalid(policydb, &ctx_new))
3659 goto out_free;
3660
3661 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3662 if (rc)
3663 goto out_free;
3664
3665 security_netlbl_cache_add(secattr, *sid);
3666
3667 ebitmap_destroy(&ctx_new.range.level[0].cat);
3668 } else
3669 *sid = SECSID_NULL;
3670
3671 read_unlock(&state->ss->policy_rwlock);
3672 return 0;
3673out_free:
3674 ebitmap_destroy(&ctx_new.range.level[0].cat);
3675out:
3676 read_unlock(&state->ss->policy_rwlock);
3677 return rc;
3678}
3679
3680/**
3681 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3682 * @sid: the SELinux SID
3683 * @secattr: the NetLabel packet security attributes
3684 *
3685 * Description:
3686 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3687 * Returns zero on success, negative values on failure.
3688 *
3689 */
3690int security_netlbl_sid_to_secattr(struct selinux_state *state,
3691 u32 sid, struct netlbl_lsm_secattr *secattr)
3692{
3693 struct policydb *policydb = &state->ss->policydb;
3694 int rc;
3695 struct context *ctx;
3696
3697 if (!selinux_initialized(state))
3698 return 0;
3699
3700 read_lock(&state->ss->policy_rwlock);
3701
3702 rc = -ENOENT;
3703 ctx = sidtab_search(state->ss->sidtab, sid);
3704 if (ctx == NULL)
3705 goto out;
3706
3707 rc = -ENOMEM;
3708 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3709 GFP_ATOMIC);
3710 if (secattr->domain == NULL)
3711 goto out;
3712
3713 secattr->attr.secid = sid;
3714 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3715 mls_export_netlbl_lvl(policydb, ctx, secattr);
3716 rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3717out:
3718 read_unlock(&state->ss->policy_rwlock);
3719 return rc;
3720}
3721#endif /* CONFIG_NETLABEL */
3722
3723/**
3724 * security_read_policy - read the policy.
3725 * @data: binary policy data
3726 * @len: length of data in bytes
3727 *
3728 */
3729int security_read_policy(struct selinux_state *state,
3730 void **data, size_t *len)
3731{
3732 struct policydb *policydb = &state->ss->policydb;
3733 int rc;
3734 struct policy_file fp;
3735
3736 if (!selinux_initialized(state))
3737 return -EINVAL;
3738
3739 *len = security_policydb_len(state);
3740
3741 *data = vmalloc_user(*len);
3742 if (!*data)
3743 return -ENOMEM;
3744
3745 fp.data = *data;
3746 fp.len = *len;
3747
3748 read_lock(&state->ss->policy_rwlock);
3749 rc = policydb_write(policydb, &fp);
3750 read_unlock(&state->ss->policy_rwlock);
3751
3752 if (rc)
3753 return rc;
3754
3755 *len = (unsigned long)fp.data - (unsigned long)*data;
3756 return 0;
3757
3758}
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
71struct selinux_policy_convert_data {
72 struct convert_context_args args;
73 struct sidtab_convert_params sidtab_params;
74};
75
76/* Forward declaration. */
77static int context_struct_to_string(struct policydb *policydb,
78 struct context *context,
79 char **scontext,
80 u32 *scontext_len);
81
82static 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
88static 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
95static 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(++i, 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(pol, 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(pol, p_out->value,
146 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;
166err:
167 kfree(out_map->mapping);
168 out_map->mapping = NULL;
169 return -EINVAL;
170}
171
172/*
173 * Get real, policy values from mapped values
174 */
175
176static 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 */
187static 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
199static 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
238int 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 */
264static 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(&r1->dominates,
314 val2 - 1);
315 continue;
316 case CEXPR_DOMBY:
317 s[++sp] = ebitmap_get_bit(&r2->dominates,
318 val1 - 1);
319 continue;
320 case CEXPR_INCOMP:
321 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
322 val2 - 1) &&
323 !ebitmap_get_bit(&r2->dominates,
324 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;
354mls_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(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->names, val1 - 1);
420 break;
421 case CEXPR_NEQ:
422 s[++sp] = !ebitmap_get_bit(&e->names, 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 */
443static 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
455static 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(policydb, SYM_CLASSES, 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(&common_dat->permissions.table,
483 dump_masked_av_helper, permission_names) < 0)
484 goto out;
485
486 if (hashtab_map(&tclass_dat->permissions.table,
487 dump_masked_av_helper, permission_names) < 0)
488 goto out;
489
490 /* get scontext/tcontext in text form */
491 if (context_struct_to_string(policydb, scontext,
492 &scontext_name, &length) < 0)
493 goto out;
494
495 if (context_struct_to_string(policydb, tcontext,
496 &tcontext_name, &length) < 0)
497 goto out;
498
499 /* audit a message */
500 ab = audit_log_start(audit_context(),
501 GFP_ATOMIC, AUDIT_SELINUX_ERR);
502 if (!ab)
503 goto out;
504
505 audit_log_format(ab, "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, "%s%s",
516 need_comma ? "," : "",
517 permission_names[index]
518 ? permission_names[index] : "????");
519 need_comma = true;
520 }
521 audit_log_end(ab);
522out:
523 /* release scontext/tcontext */
524 kfree(tcontext_name);
525 kfree(scontext_name);
526}
527
528/*
529 * security_boundary_permission - drops violated permissions
530 * on boundary constraint.
531 */
532static 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, &lo_scontext,
566 tcontextp,
567 tclass,
568 &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, masked, "bounds");
582}
583
584/*
585 * flag which drivers have permissions
586 * only looking for ioctl based extended permissions
587 */
588void 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 */
611static 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(&policydb->te_avtab,
656 &avkey);
657 node;
658 node = avtab_search_node_next(node, 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(&policydb->te_cond_avtab, &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 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
716static 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(p, sidtab, oentry, &o, &olen))
728 goto out;
729 if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen))
730 goto out;
731 if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen))
732 goto out;
733 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
734 "op=security_validate_transition seresult=denied"
735 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
736 o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
737out:
738 kfree(o);
739 kfree(n);
740 kfree(t);
741
742 if (!enforcing_enabled())
743 return 0;
744 return -EPERM;
745}
746
747static 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(&policy->map, 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(sidtab, 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(sidtab, 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(sidtab, 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, &oentry->context,
809 &nentry->context, &tentry->context,
810 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
824out:
825 rcu_read_unlock();
826 return rc;
827}
828
829int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid,
830 u16 tclass)
831{
832 return security_compute_validatetrans(oldsid, newsid, tasksid,
833 tclass, true);
834}
835
836int 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, 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 */
852int 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(sidtab, 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(sidtab, 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, old_entry,
915 &old_name, &length) &&
916 !sidtab_entry_to_string(policydb, sidtab, new_entry,
917 &new_name, &length)) {
918 audit_log(audit_context(),
919 GFP_ATOMIC, AUDIT_SELINUX_ERR,
920 "op=security_bounded_transition "
921 "seresult=denied "
922 "oldcontext=%s newcontext=%s",
923 old_name, new_name);
924 }
925 kfree(new_name);
926 kfree(old_name);
927 }
928out:
929 rcu_read_unlock();
930
931 return rc;
932}
933
934static 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
946void 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
1000void 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(sidtab, 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(sidtab, 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(&policy->map, 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(&policydb->te_avtab,
1067 &avkey);
1068 node;
1069 node = avtab_search_node_next(node, avkey.specified))
1070 services_compute_xperms_decision(xpermd, node);
1071
1072 cond_compute_xperms(&policydb->te_cond_avtab,
1073 &avkey, xpermd);
1074 }
1075 }
1076out:
1077 rcu_read_unlock();
1078 return;
1079allow:
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 */
1095void 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(sidtab, 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(&policydb->permissive_map, scontext->type))
1126 avd->flags |= AVD_FLAGS_PERMISSIVE;
1127
1128 tcontext = sidtab_search(sidtab, 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(&policy->map, 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(&policy->map, orig_tclass, avd,
1144 policydb->allow_unknown);
1145out:
1146 rcu_read_unlock();
1147 return;
1148allow:
1149 avd->allowed = 0xffffffff;
1150 goto out;
1151}
1152
1153void 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(sidtab, 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(&policydb->permissive_map, scontext->type))
1181 avd->flags |= AVD_FLAGS_PERMISSIVE;
1182
1183 tcontext = sidtab_search(sidtab, 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;
1201allow:
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 */
1213static 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(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(*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(scontextp, "%s:%s:%s",
1252 sym_name(p, SYM_USERS, context->user - 1),
1253 sym_name(p, SYM_ROLES, context->role - 1),
1254 sym_name(p, SYM_TYPES, context->type - 1));
1255
1256 mls_sid_to_context(p, context, &scontextp);
1257
1258 *scontextp = 0;
1259
1260 return 0;
1261}
1262
1263static 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(sidtab, entry, scontext, scontext_len);
1269
1270 if (rc != -ENOENT)
1271 return rc;
1272
1273 rc = context_struct_to_string(p, &entry->context, scontext,
1274 scontext_len);
1275 if (!rc && scontext)
1276 sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len);
1277 return rc;
1278}
1279
1280#include "initial_sid_to_string.h"
1281
1282int 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(policy->sidtab, page);
1296 rcu_read_unlock();
1297
1298 return rc;
1299}
1300
1301const 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
1308static 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;
1326
1327 /*
1328 * Before the policy is loaded, translate
1329 * SECINITSID_INIT to "kernel", because systemd and
1330 * libselinux < 2.6 take a getcon_raw() result that is
1331 * both non-null and not "kernel" to mean that a policy
1332 * is already loaded.
1333 */
1334 if (sid == SECINITSID_INIT)
1335 sid = SECINITSID_KERNEL;
1336
1337 s = initial_sid_to_string[sid];
1338 if (!s)
1339 return -EINVAL;
1340 *scontext_len = strlen(s) + 1;
1341 if (!scontext)
1342 return 0;
1343 scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC);
1344 if (!scontextp)
1345 return -ENOMEM;
1346 *scontext = scontextp;
1347 return 0;
1348 }
1349 pr_err("SELinux: %s: called before initial "
1350 "load_policy on unknown SID %d\n", __func__, sid);
1351 return -EINVAL;
1352 }
1353 rcu_read_lock();
1354 policy = rcu_dereference(selinux_state.policy);
1355 policydb = &policy->policydb;
1356 sidtab = policy->sidtab;
1357
1358 if (force)
1359 entry = sidtab_search_entry_force(sidtab, sid);
1360 else
1361 entry = sidtab_search_entry(sidtab, sid);
1362 if (!entry) {
1363 pr_err("SELinux: %s: unrecognized SID %d\n",
1364 __func__, sid);
1365 rc = -EINVAL;
1366 goto out_unlock;
1367 }
1368 if (only_invalid && !entry->context.len)
1369 goto out_unlock;
1370
1371 rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext,
1372 scontext_len);
1373
1374out_unlock:
1375 rcu_read_unlock();
1376 return rc;
1377
1378}
1379
1380/**
1381 * security_sid_to_context - Obtain a context for a given SID.
1382 * @sid: security identifier, SID
1383 * @scontext: security context
1384 * @scontext_len: length in bytes
1385 *
1386 * Write the string representation of the context associated with @sid
1387 * into a dynamically allocated string of the correct size. Set @scontext
1388 * to point to this string and set @scontext_len to the length of the string.
1389 */
1390int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1391{
1392 return security_sid_to_context_core(sid, scontext,
1393 scontext_len, 0, 0);
1394}
1395
1396int security_sid_to_context_force(u32 sid,
1397 char **scontext, u32 *scontext_len)
1398{
1399 return security_sid_to_context_core(sid, scontext,
1400 scontext_len, 1, 0);
1401}
1402
1403/**
1404 * security_sid_to_context_inval - Obtain a context for a given SID if it
1405 * is invalid.
1406 * @sid: security identifier, SID
1407 * @scontext: security context
1408 * @scontext_len: length in bytes
1409 *
1410 * Write the string representation of the context associated with @sid
1411 * into a dynamically allocated string of the correct size, but only if the
1412 * context is invalid in the current policy. Set @scontext to point to
1413 * this string (or NULL if the context is valid) and set @scontext_len to
1414 * the length of the string (or 0 if the context is valid).
1415 */
1416int security_sid_to_context_inval(u32 sid,
1417 char **scontext, u32 *scontext_len)
1418{
1419 return security_sid_to_context_core(sid, scontext,
1420 scontext_len, 1, 1);
1421}
1422
1423/*
1424 * Caveat: Mutates scontext.
1425 */
1426static int string_to_context_struct(struct policydb *pol,
1427 struct sidtab *sidtabp,
1428 char *scontext,
1429 struct context *ctx,
1430 u32 def_sid)
1431{
1432 struct role_datum *role;
1433 struct type_datum *typdatum;
1434 struct user_datum *usrdatum;
1435 char *scontextp, *p, oldc;
1436 int rc = 0;
1437
1438 context_init(ctx);
1439
1440 /* Parse the security context. */
1441
1442 rc = -EINVAL;
1443 scontextp = scontext;
1444
1445 /* Extract the user. */
1446 p = scontextp;
1447 while (*p && *p != ':')
1448 p++;
1449
1450 if (*p == 0)
1451 goto out;
1452
1453 *p++ = 0;
1454
1455 usrdatum = symtab_search(&pol->p_users, scontextp);
1456 if (!usrdatum)
1457 goto out;
1458
1459 ctx->user = usrdatum->value;
1460
1461 /* Extract role. */
1462 scontextp = p;
1463 while (*p && *p != ':')
1464 p++;
1465
1466 if (*p == 0)
1467 goto out;
1468
1469 *p++ = 0;
1470
1471 role = symtab_search(&pol->p_roles, scontextp);
1472 if (!role)
1473 goto out;
1474 ctx->role = role->value;
1475
1476 /* Extract type. */
1477 scontextp = p;
1478 while (*p && *p != ':')
1479 p++;
1480 oldc = *p;
1481 *p++ = 0;
1482
1483 typdatum = symtab_search(&pol->p_types, scontextp);
1484 if (!typdatum || typdatum->attribute)
1485 goto out;
1486
1487 ctx->type = typdatum->value;
1488
1489 rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid);
1490 if (rc)
1491 goto out;
1492
1493 /* Check the validity of the new context. */
1494 rc = -EINVAL;
1495 if (!policydb_context_isvalid(pol, ctx))
1496 goto out;
1497 rc = 0;
1498out:
1499 if (rc)
1500 context_destroy(ctx);
1501 return rc;
1502}
1503
1504static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1505 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1506 int force)
1507{
1508 struct selinux_policy *policy;
1509 struct policydb *policydb;
1510 struct sidtab *sidtab;
1511 char *scontext2, *str = NULL;
1512 struct context context;
1513 int rc = 0;
1514
1515 /* An empty security context is never valid. */
1516 if (!scontext_len)
1517 return -EINVAL;
1518
1519 /* Copy the string to allow changes and ensure a NUL terminator */
1520 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags);
1521 if (!scontext2)
1522 return -ENOMEM;
1523
1524 if (!selinux_initialized()) {
1525 u32 i;
1526
1527 for (i = 1; i < SECINITSID_NUM; i++) {
1528 const char *s = initial_sid_to_string[i];
1529
1530 if (s && !strcmp(s, scontext2)) {
1531 *sid = i;
1532 goto out;
1533 }
1534 }
1535 *sid = SECINITSID_KERNEL;
1536 goto out;
1537 }
1538 *sid = SECSID_NULL;
1539
1540 if (force) {
1541 /* Save another copy for storing in uninterpreted form */
1542 rc = -ENOMEM;
1543 str = kstrdup(scontext2, gfp_flags);
1544 if (!str)
1545 goto out;
1546 }
1547retry:
1548 rcu_read_lock();
1549 policy = rcu_dereference(selinux_state.policy);
1550 policydb = &policy->policydb;
1551 sidtab = policy->sidtab;
1552 rc = string_to_context_struct(policydb, sidtab, scontext2,
1553 &context, def_sid);
1554 if (rc == -EINVAL && force) {
1555 context.str = str;
1556 context.len = strlen(str) + 1;
1557 str = NULL;
1558 } else if (rc)
1559 goto out_unlock;
1560 rc = sidtab_context_to_sid(sidtab, &context, sid);
1561 if (rc == -ESTALE) {
1562 rcu_read_unlock();
1563 if (context.str) {
1564 str = context.str;
1565 context.str = NULL;
1566 }
1567 context_destroy(&context);
1568 goto retry;
1569 }
1570 context_destroy(&context);
1571out_unlock:
1572 rcu_read_unlock();
1573out:
1574 kfree(scontext2);
1575 kfree(str);
1576 return rc;
1577}
1578
1579/**
1580 * security_context_to_sid - Obtain a SID for a given security context.
1581 * @scontext: security context
1582 * @scontext_len: length in bytes
1583 * @sid: security identifier, SID
1584 * @gfp: context for the allocation
1585 *
1586 * Obtains a SID associated with the security context that
1587 * has the string representation specified by @scontext.
1588 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1589 * memory is available, or 0 on success.
1590 */
1591int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid,
1592 gfp_t gfp)
1593{
1594 return security_context_to_sid_core(scontext, scontext_len,
1595 sid, SECSID_NULL, gfp, 0);
1596}
1597
1598int security_context_str_to_sid(const char *scontext, u32 *sid, gfp_t gfp)
1599{
1600 return security_context_to_sid(scontext, strlen(scontext),
1601 sid, gfp);
1602}
1603
1604/**
1605 * security_context_to_sid_default - Obtain a SID for a given security context,
1606 * falling back to specified default if needed.
1607 *
1608 * @scontext: security context
1609 * @scontext_len: length in bytes
1610 * @sid: security identifier, SID
1611 * @def_sid: default SID to assign on error
1612 * @gfp_flags: the allocator get-free-page (GFP) flags
1613 *
1614 * Obtains a SID associated with the security context that
1615 * has the string representation specified by @scontext.
1616 * The default SID is passed to the MLS layer to be used to allow
1617 * kernel labeling of the MLS field if the MLS field is not present
1618 * (for upgrading to MLS without full relabel).
1619 * Implicitly forces adding of the context even if it cannot be mapped yet.
1620 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1621 * memory is available, or 0 on success.
1622 */
1623int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1624 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1625{
1626 return security_context_to_sid_core(scontext, scontext_len,
1627 sid, def_sid, gfp_flags, 1);
1628}
1629
1630int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1631 u32 *sid)
1632{
1633 return security_context_to_sid_core(scontext, scontext_len,
1634 sid, SECSID_NULL, GFP_KERNEL, 1);
1635}
1636
1637static int compute_sid_handle_invalid_context(
1638 struct selinux_policy *policy,
1639 struct sidtab_entry *sentry,
1640 struct sidtab_entry *tentry,
1641 u16 tclass,
1642 struct context *newcontext)
1643{
1644 struct policydb *policydb = &policy->policydb;
1645 struct sidtab *sidtab = policy->sidtab;
1646 char *s = NULL, *t = NULL, *n = NULL;
1647 u32 slen, tlen, nlen;
1648 struct audit_buffer *ab;
1649
1650 if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen))
1651 goto out;
1652 if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen))
1653 goto out;
1654 if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1655 goto out;
1656 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR);
1657 if (!ab)
1658 goto out;
1659 audit_log_format(ab,
1660 "op=security_compute_sid invalid_context=");
1661 /* no need to record the NUL with untrusted strings */
1662 audit_log_n_untrustedstring(ab, n, nlen - 1);
1663 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s",
1664 s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1665 audit_log_end(ab);
1666out:
1667 kfree(s);
1668 kfree(t);
1669 kfree(n);
1670 if (!enforcing_enabled())
1671 return 0;
1672 return -EACCES;
1673}
1674
1675static void filename_compute_type(struct policydb *policydb,
1676 struct context *newcontext,
1677 u32 stype, u32 ttype, u16 tclass,
1678 const char *objname)
1679{
1680 struct filename_trans_key ft;
1681 struct filename_trans_datum *datum;
1682
1683 /*
1684 * Most filename trans rules are going to live in specific directories
1685 * like /dev or /var/run. This bitmap will quickly skip rule searches
1686 * if the ttype does not contain any rules.
1687 */
1688 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1689 return;
1690
1691 ft.ttype = ttype;
1692 ft.tclass = tclass;
1693 ft.name = objname;
1694
1695 datum = policydb_filenametr_search(policydb, &ft);
1696 while (datum) {
1697 if (ebitmap_get_bit(&datum->stypes, stype - 1)) {
1698 newcontext->type = datum->otype;
1699 return;
1700 }
1701 datum = datum->next;
1702 }
1703}
1704
1705static int security_compute_sid(u32 ssid,
1706 u32 tsid,
1707 u16 orig_tclass,
1708 u16 specified,
1709 const char *objname,
1710 u32 *out_sid,
1711 bool kern)
1712{
1713 struct selinux_policy *policy;
1714 struct policydb *policydb;
1715 struct sidtab *sidtab;
1716 struct class_datum *cladatum;
1717 struct context *scontext, *tcontext, newcontext;
1718 struct sidtab_entry *sentry, *tentry;
1719 struct avtab_key avkey;
1720 struct avtab_node *avnode, *node;
1721 u16 tclass;
1722 int rc = 0;
1723 bool sock;
1724
1725 if (!selinux_initialized()) {
1726 switch (orig_tclass) {
1727 case SECCLASS_PROCESS: /* kernel value */
1728 *out_sid = ssid;
1729 break;
1730 default:
1731 *out_sid = tsid;
1732 break;
1733 }
1734 goto out;
1735 }
1736
1737retry:
1738 cladatum = NULL;
1739 context_init(&newcontext);
1740
1741 rcu_read_lock();
1742
1743 policy = rcu_dereference(selinux_state.policy);
1744
1745 if (kern) {
1746 tclass = unmap_class(&policy->map, orig_tclass);
1747 sock = security_is_socket_class(orig_tclass);
1748 } else {
1749 tclass = orig_tclass;
1750 sock = security_is_socket_class(map_class(&policy->map,
1751 tclass));
1752 }
1753
1754 policydb = &policy->policydb;
1755 sidtab = policy->sidtab;
1756
1757 sentry = sidtab_search_entry(sidtab, ssid);
1758 if (!sentry) {
1759 pr_err("SELinux: %s: unrecognized SID %d\n",
1760 __func__, ssid);
1761 rc = -EINVAL;
1762 goto out_unlock;
1763 }
1764 tentry = sidtab_search_entry(sidtab, tsid);
1765 if (!tentry) {
1766 pr_err("SELinux: %s: unrecognized SID %d\n",
1767 __func__, tsid);
1768 rc = -EINVAL;
1769 goto out_unlock;
1770 }
1771
1772 scontext = &sentry->context;
1773 tcontext = &tentry->context;
1774
1775 if (tclass && tclass <= policydb->p_classes.nprim)
1776 cladatum = policydb->class_val_to_struct[tclass - 1];
1777
1778 /* Set the user identity. */
1779 switch (specified) {
1780 case AVTAB_TRANSITION:
1781 case AVTAB_CHANGE:
1782 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1783 newcontext.user = tcontext->user;
1784 } else {
1785 /* notice this gets both DEFAULT_SOURCE and unset */
1786 /* Use the process user identity. */
1787 newcontext.user = scontext->user;
1788 }
1789 break;
1790 case AVTAB_MEMBER:
1791 /* Use the related object owner. */
1792 newcontext.user = tcontext->user;
1793 break;
1794 }
1795
1796 /* Set the role to default values. */
1797 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1798 newcontext.role = scontext->role;
1799 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1800 newcontext.role = tcontext->role;
1801 } else {
1802 if ((tclass == policydb->process_class) || sock)
1803 newcontext.role = scontext->role;
1804 else
1805 newcontext.role = OBJECT_R_VAL;
1806 }
1807
1808 /* Set the type to default values. */
1809 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1810 newcontext.type = scontext->type;
1811 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1812 newcontext.type = tcontext->type;
1813 } else {
1814 if ((tclass == policydb->process_class) || sock) {
1815 /* Use the type of process. */
1816 newcontext.type = scontext->type;
1817 } else {
1818 /* Use the type of the related object. */
1819 newcontext.type = tcontext->type;
1820 }
1821 }
1822
1823 /* Look for a type transition/member/change rule. */
1824 avkey.source_type = scontext->type;
1825 avkey.target_type = tcontext->type;
1826 avkey.target_class = tclass;
1827 avkey.specified = specified;
1828 avnode = avtab_search_node(&policydb->te_avtab, &avkey);
1829
1830 /* If no permanent rule, also check for enabled conditional rules */
1831 if (!avnode) {
1832 node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1833 for (; node; node = avtab_search_node_next(node, specified)) {
1834 if (node->key.specified & AVTAB_ENABLED) {
1835 avnode = node;
1836 break;
1837 }
1838 }
1839 }
1840
1841 if (avnode) {
1842 /* Use the type from the type transition/member/change rule. */
1843 newcontext.type = avnode->datum.u.data;
1844 }
1845
1846 /* if we have a objname this is a file trans check so check those rules */
1847 if (objname)
1848 filename_compute_type(policydb, &newcontext, scontext->type,
1849 tcontext->type, tclass, objname);
1850
1851 /* Check for class-specific changes. */
1852 if (specified & AVTAB_TRANSITION) {
1853 /* Look for a role transition rule. */
1854 struct role_trans_datum *rtd;
1855 struct role_trans_key rtk = {
1856 .role = scontext->role,
1857 .type = tcontext->type,
1858 .tclass = tclass,
1859 };
1860
1861 rtd = policydb_roletr_search(policydb, &rtk);
1862 if (rtd)
1863 newcontext.role = rtd->new_role;
1864 }
1865
1866 /* Set the MLS attributes.
1867 This is done last because it may allocate memory. */
1868 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1869 &newcontext, sock);
1870 if (rc)
1871 goto out_unlock;
1872
1873 /* Check the validity of the context. */
1874 if (!policydb_context_isvalid(policydb, &newcontext)) {
1875 rc = compute_sid_handle_invalid_context(policy, sentry,
1876 tentry, tclass,
1877 &newcontext);
1878 if (rc)
1879 goto out_unlock;
1880 }
1881 /* Obtain the sid for the context. */
1882 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1883 if (rc == -ESTALE) {
1884 rcu_read_unlock();
1885 context_destroy(&newcontext);
1886 goto retry;
1887 }
1888out_unlock:
1889 rcu_read_unlock();
1890 context_destroy(&newcontext);
1891out:
1892 return rc;
1893}
1894
1895/**
1896 * security_transition_sid - Compute the SID for a new subject/object.
1897 * @ssid: source security identifier
1898 * @tsid: target security identifier
1899 * @tclass: target security class
1900 * @qstr: object name
1901 * @out_sid: security identifier for new subject/object
1902 *
1903 * Compute a SID to use for labeling a new subject or object in the
1904 * class @tclass based on a SID pair (@ssid, @tsid).
1905 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1906 * if insufficient memory is available, or %0 if the new SID was
1907 * computed successfully.
1908 */
1909int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1910 const struct qstr *qstr, u32 *out_sid)
1911{
1912 return security_compute_sid(ssid, tsid, tclass,
1913 AVTAB_TRANSITION,
1914 qstr ? qstr->name : NULL, out_sid, true);
1915}
1916
1917int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1918 const char *objname, u32 *out_sid)
1919{
1920 return security_compute_sid(ssid, tsid, tclass,
1921 AVTAB_TRANSITION,
1922 objname, out_sid, false);
1923}
1924
1925/**
1926 * security_member_sid - Compute the SID for member selection.
1927 * @ssid: source security identifier
1928 * @tsid: target security identifier
1929 * @tclass: target security class
1930 * @out_sid: security identifier for selected member
1931 *
1932 * Compute a SID to use when selecting a member of a polyinstantiated
1933 * object of class @tclass based on a SID pair (@ssid, @tsid).
1934 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1935 * if insufficient memory is available, or %0 if the SID was
1936 * computed successfully.
1937 */
1938int security_member_sid(u32 ssid,
1939 u32 tsid,
1940 u16 tclass,
1941 u32 *out_sid)
1942{
1943 return security_compute_sid(ssid, tsid, tclass,
1944 AVTAB_MEMBER, NULL,
1945 out_sid, false);
1946}
1947
1948/**
1949 * security_change_sid - Compute the SID for object relabeling.
1950 * @ssid: source security identifier
1951 * @tsid: target security identifier
1952 * @tclass: target security class
1953 * @out_sid: security identifier for selected member
1954 *
1955 * Compute a SID to use for relabeling an object of class @tclass
1956 * based on a SID pair (@ssid, @tsid).
1957 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1958 * if insufficient memory is available, or %0 if the SID was
1959 * computed successfully.
1960 */
1961int security_change_sid(u32 ssid,
1962 u32 tsid,
1963 u16 tclass,
1964 u32 *out_sid)
1965{
1966 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1967 out_sid, false);
1968}
1969
1970static inline int convert_context_handle_invalid_context(
1971 struct policydb *policydb,
1972 struct context *context)
1973{
1974 char *s;
1975 u32 len;
1976
1977 if (enforcing_enabled())
1978 return -EINVAL;
1979
1980 if (!context_struct_to_string(policydb, context, &s, &len)) {
1981 pr_warn("SELinux: Context %s would be invalid if enforcing\n",
1982 s);
1983 kfree(s);
1984 }
1985 return 0;
1986}
1987
1988/**
1989 * services_convert_context - Convert a security context across policies.
1990 * @args: populated convert_context_args struct
1991 * @oldc: original context
1992 * @newc: converted context
1993 * @gfp_flags: allocation flags
1994 *
1995 * Convert the values in the security context structure @oldc from the values
1996 * specified in the policy @args->oldp to the values specified in the policy
1997 * @args->newp, storing the new context in @newc, and verifying that the
1998 * context is valid under the new policy.
1999 */
2000int services_convert_context(struct convert_context_args *args,
2001 struct context *oldc, struct context *newc,
2002 gfp_t gfp_flags)
2003{
2004 struct ocontext *oc;
2005 struct role_datum *role;
2006 struct type_datum *typdatum;
2007 struct user_datum *usrdatum;
2008 char *s;
2009 u32 len;
2010 int rc;
2011
2012 if (oldc->str) {
2013 s = kstrdup(oldc->str, gfp_flags);
2014 if (!s)
2015 return -ENOMEM;
2016
2017 rc = string_to_context_struct(args->newp, NULL, s, newc, SECSID_NULL);
2018 if (rc == -EINVAL) {
2019 /*
2020 * Retain string representation for later mapping.
2021 *
2022 * IMPORTANT: We need to copy the contents of oldc->str
2023 * back into s again because string_to_context_struct()
2024 * may have garbled it.
2025 */
2026 memcpy(s, oldc->str, oldc->len);
2027 context_init(newc);
2028 newc->str = s;
2029 newc->len = oldc->len;
2030 return 0;
2031 }
2032 kfree(s);
2033 if (rc) {
2034 /* Other error condition, e.g. ENOMEM. */
2035 pr_err("SELinux: Unable to map context %s, rc = %d.\n",
2036 oldc->str, -rc);
2037 return rc;
2038 }
2039 pr_info("SELinux: Context %s became valid (mapped).\n",
2040 oldc->str);
2041 return 0;
2042 }
2043
2044 context_init(newc);
2045
2046 /* Convert the user. */
2047 usrdatum = symtab_search(&args->newp->p_users,
2048 sym_name(args->oldp, SYM_USERS, oldc->user - 1));
2049 if (!usrdatum)
2050 goto bad;
2051 newc->user = usrdatum->value;
2052
2053 /* Convert the role. */
2054 role = symtab_search(&args->newp->p_roles,
2055 sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
2056 if (!role)
2057 goto bad;
2058 newc->role = role->value;
2059
2060 /* Convert the type. */
2061 typdatum = symtab_search(&args->newp->p_types,
2062 sym_name(args->oldp, SYM_TYPES, oldc->type - 1));
2063 if (!typdatum)
2064 goto bad;
2065 newc->type = typdatum->value;
2066
2067 /* Convert the MLS fields if dealing with MLS policies */
2068 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2069 rc = mls_convert_context(args->oldp, args->newp, oldc, newc);
2070 if (rc)
2071 goto bad;
2072 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2073 /*
2074 * Switching between non-MLS and MLS policy:
2075 * ensure that the MLS fields of the context for all
2076 * existing entries in the sidtab are filled in with a
2077 * suitable default value, likely taken from one of the
2078 * initial SIDs.
2079 */
2080 oc = args->newp->ocontexts[OCON_ISID];
2081 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2082 oc = oc->next;
2083 if (!oc) {
2084 pr_err("SELinux: unable to look up"
2085 " the initial SIDs list\n");
2086 goto bad;
2087 }
2088 rc = mls_range_set(newc, &oc->context[0].range);
2089 if (rc)
2090 goto bad;
2091 }
2092
2093 /* Check the validity of the new context. */
2094 if (!policydb_context_isvalid(args->newp, newc)) {
2095 rc = convert_context_handle_invalid_context(args->oldp, oldc);
2096 if (rc)
2097 goto bad;
2098 }
2099
2100 return 0;
2101bad:
2102 /* Map old representation to string and save it. */
2103 rc = context_struct_to_string(args->oldp, oldc, &s, &len);
2104 if (rc)
2105 return rc;
2106 context_destroy(newc);
2107 newc->str = s;
2108 newc->len = len;
2109 pr_info("SELinux: Context %s became invalid (unmapped).\n",
2110 newc->str);
2111 return 0;
2112}
2113
2114static void security_load_policycaps(struct selinux_policy *policy)
2115{
2116 struct policydb *p;
2117 unsigned int i;
2118 struct ebitmap_node *node;
2119
2120 p = &policy->policydb;
2121
2122 for (i = 0; i < ARRAY_SIZE(selinux_state.policycap); i++)
2123 WRITE_ONCE(selinux_state.policycap[i],
2124 ebitmap_get_bit(&p->policycaps, i));
2125
2126 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2127 pr_info("SELinux: policy capability %s=%d\n",
2128 selinux_policycap_names[i],
2129 ebitmap_get_bit(&p->policycaps, i));
2130
2131 ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2132 if (i >= ARRAY_SIZE(selinux_policycap_names))
2133 pr_info("SELinux: unknown policy capability %u\n",
2134 i);
2135 }
2136}
2137
2138static int security_preserve_bools(struct selinux_policy *oldpolicy,
2139 struct selinux_policy *newpolicy);
2140
2141static void selinux_policy_free(struct selinux_policy *policy)
2142{
2143 if (!policy)
2144 return;
2145
2146 sidtab_destroy(policy->sidtab);
2147 kfree(policy->map.mapping);
2148 policydb_destroy(&policy->policydb);
2149 kfree(policy->sidtab);
2150 kfree(policy);
2151}
2152
2153static void selinux_policy_cond_free(struct selinux_policy *policy)
2154{
2155 cond_policydb_destroy_dup(&policy->policydb);
2156 kfree(policy);
2157}
2158
2159void selinux_policy_cancel(struct selinux_load_state *load_state)
2160{
2161 struct selinux_state *state = &selinux_state;
2162 struct selinux_policy *oldpolicy;
2163
2164 oldpolicy = rcu_dereference_protected(state->policy,
2165 lockdep_is_held(&state->policy_mutex));
2166
2167 sidtab_cancel_convert(oldpolicy->sidtab);
2168 selinux_policy_free(load_state->policy);
2169 kfree(load_state->convert_data);
2170}
2171
2172static void selinux_notify_policy_change(u32 seqno)
2173{
2174 /* Flush external caches and notify userspace of policy load */
2175 avc_ss_reset(seqno);
2176 selnl_notify_policyload(seqno);
2177 selinux_status_update_policyload(seqno);
2178 selinux_netlbl_cache_invalidate();
2179 selinux_xfrm_notify_policyload();
2180 selinux_ima_measure_state_locked();
2181}
2182
2183void selinux_policy_commit(struct selinux_load_state *load_state)
2184{
2185 struct selinux_state *state = &selinux_state;
2186 struct selinux_policy *oldpolicy, *newpolicy = load_state->policy;
2187 unsigned long flags;
2188 u32 seqno;
2189
2190 oldpolicy = rcu_dereference_protected(state->policy,
2191 lockdep_is_held(&state->policy_mutex));
2192
2193 /* If switching between different policy types, log MLS status */
2194 if (oldpolicy) {
2195 if (oldpolicy->policydb.mls_enabled && !newpolicy->policydb.mls_enabled)
2196 pr_info("SELinux: Disabling MLS support...\n");
2197 else if (!oldpolicy->policydb.mls_enabled && newpolicy->policydb.mls_enabled)
2198 pr_info("SELinux: Enabling MLS support...\n");
2199 }
2200
2201 /* Set latest granting seqno for new policy. */
2202 if (oldpolicy)
2203 newpolicy->latest_granting = oldpolicy->latest_granting + 1;
2204 else
2205 newpolicy->latest_granting = 1;
2206 seqno = newpolicy->latest_granting;
2207
2208 /* Install the new policy. */
2209 if (oldpolicy) {
2210 sidtab_freeze_begin(oldpolicy->sidtab, &flags);
2211 rcu_assign_pointer(state->policy, newpolicy);
2212 sidtab_freeze_end(oldpolicy->sidtab, &flags);
2213 } else {
2214 rcu_assign_pointer(state->policy, newpolicy);
2215 }
2216
2217 /* Load the policycaps from the new policy */
2218 security_load_policycaps(newpolicy);
2219
2220 if (!selinux_initialized()) {
2221 /*
2222 * After first policy load, the security server is
2223 * marked as initialized and ready to handle requests and
2224 * any objects created prior to policy load are then labeled.
2225 */
2226 selinux_mark_initialized();
2227 selinux_complete_init();
2228 }
2229
2230 /* Free the old policy */
2231 synchronize_rcu();
2232 selinux_policy_free(oldpolicy);
2233 kfree(load_state->convert_data);
2234
2235 /* Notify others of the policy change */
2236 selinux_notify_policy_change(seqno);
2237}
2238
2239/**
2240 * security_load_policy - Load a security policy configuration.
2241 * @data: binary policy data
2242 * @len: length of data in bytes
2243 * @load_state: policy load state
2244 *
2245 * Load a new set of security policy configuration data,
2246 * validate it and convert the SID table as necessary.
2247 * This function will flush the access vector cache after
2248 * loading the new policy.
2249 */
2250int security_load_policy(void *data, size_t len,
2251 struct selinux_load_state *load_state)
2252{
2253 struct selinux_state *state = &selinux_state;
2254 struct selinux_policy *newpolicy, *oldpolicy;
2255 struct selinux_policy_convert_data *convert_data;
2256 int rc = 0;
2257 struct policy_file file = { data, len }, *fp = &file;
2258
2259 newpolicy = kzalloc(sizeof(*newpolicy), GFP_KERNEL);
2260 if (!newpolicy)
2261 return -ENOMEM;
2262
2263 newpolicy->sidtab = kzalloc(sizeof(*newpolicy->sidtab), GFP_KERNEL);
2264 if (!newpolicy->sidtab) {
2265 rc = -ENOMEM;
2266 goto err_policy;
2267 }
2268
2269 rc = policydb_read(&newpolicy->policydb, fp);
2270 if (rc)
2271 goto err_sidtab;
2272
2273 newpolicy->policydb.len = len;
2274 rc = selinux_set_mapping(&newpolicy->policydb, secclass_map,
2275 &newpolicy->map);
2276 if (rc)
2277 goto err_policydb;
2278
2279 rc = policydb_load_isids(&newpolicy->policydb, newpolicy->sidtab);
2280 if (rc) {
2281 pr_err("SELinux: unable to load the initial SIDs\n");
2282 goto err_mapping;
2283 }
2284
2285 if (!selinux_initialized()) {
2286 /* First policy load, so no need to preserve state from old policy */
2287 load_state->policy = newpolicy;
2288 load_state->convert_data = NULL;
2289 return 0;
2290 }
2291
2292 oldpolicy = rcu_dereference_protected(state->policy,
2293 lockdep_is_held(&state->policy_mutex));
2294
2295 /* Preserve active boolean values from the old policy */
2296 rc = security_preserve_bools(oldpolicy, newpolicy);
2297 if (rc) {
2298 pr_err("SELinux: unable to preserve booleans\n");
2299 goto err_free_isids;
2300 }
2301
2302 /*
2303 * Convert the internal representations of contexts
2304 * in the new SID table.
2305 */
2306
2307 convert_data = kmalloc(sizeof(*convert_data), GFP_KERNEL);
2308 if (!convert_data) {
2309 rc = -ENOMEM;
2310 goto err_free_isids;
2311 }
2312
2313 convert_data->args.oldp = &oldpolicy->policydb;
2314 convert_data->args.newp = &newpolicy->policydb;
2315
2316 convert_data->sidtab_params.args = &convert_data->args;
2317 convert_data->sidtab_params.target = newpolicy->sidtab;
2318
2319 rc = sidtab_convert(oldpolicy->sidtab, &convert_data->sidtab_params);
2320 if (rc) {
2321 pr_err("SELinux: unable to convert the internal"
2322 " representation of contexts in the new SID"
2323 " table\n");
2324 goto err_free_convert_data;
2325 }
2326
2327 load_state->policy = newpolicy;
2328 load_state->convert_data = convert_data;
2329 return 0;
2330
2331err_free_convert_data:
2332 kfree(convert_data);
2333err_free_isids:
2334 sidtab_destroy(newpolicy->sidtab);
2335err_mapping:
2336 kfree(newpolicy->map.mapping);
2337err_policydb:
2338 policydb_destroy(&newpolicy->policydb);
2339err_sidtab:
2340 kfree(newpolicy->sidtab);
2341err_policy:
2342 kfree(newpolicy);
2343
2344 return rc;
2345}
2346
2347/**
2348 * ocontext_to_sid - Helper to safely get sid for an ocontext
2349 * @sidtab: SID table
2350 * @c: ocontext structure
2351 * @index: index of the context entry (0 or 1)
2352 * @out_sid: pointer to the resulting SID value
2353 *
2354 * For all ocontexts except OCON_ISID the SID fields are populated
2355 * on-demand when needed. Since updating the SID value is an SMP-sensitive
2356 * operation, this helper must be used to do that safely.
2357 *
2358 * WARNING: This function may return -ESTALE, indicating that the caller
2359 * must retry the operation after re-acquiring the policy pointer!
2360 */
2361static int ocontext_to_sid(struct sidtab *sidtab, struct ocontext *c,
2362 size_t index, u32 *out_sid)
2363{
2364 int rc;
2365 u32 sid;
2366
2367 /* Ensure the associated sidtab entry is visible to this thread. */
2368 sid = smp_load_acquire(&c->sid[index]);
2369 if (!sid) {
2370 rc = sidtab_context_to_sid(sidtab, &c->context[index], &sid);
2371 if (rc)
2372 return rc;
2373
2374 /*
2375 * Ensure the new sidtab entry is visible to other threads
2376 * when they see the SID.
2377 */
2378 smp_store_release(&c->sid[index], sid);
2379 }
2380 *out_sid = sid;
2381 return 0;
2382}
2383
2384/**
2385 * security_port_sid - Obtain the SID for a port.
2386 * @protocol: protocol number
2387 * @port: port number
2388 * @out_sid: security identifier
2389 */
2390int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
2391{
2392 struct selinux_policy *policy;
2393 struct policydb *policydb;
2394 struct sidtab *sidtab;
2395 struct ocontext *c;
2396 int rc;
2397
2398 if (!selinux_initialized()) {
2399 *out_sid = SECINITSID_PORT;
2400 return 0;
2401 }
2402
2403retry:
2404 rc = 0;
2405 rcu_read_lock();
2406 policy = rcu_dereference(selinux_state.policy);
2407 policydb = &policy->policydb;
2408 sidtab = policy->sidtab;
2409
2410 c = policydb->ocontexts[OCON_PORT];
2411 while (c) {
2412 if (c->u.port.protocol == protocol &&
2413 c->u.port.low_port <= port &&
2414 c->u.port.high_port >= port)
2415 break;
2416 c = c->next;
2417 }
2418
2419 if (c) {
2420 rc = ocontext_to_sid(sidtab, c, 0, out_sid);
2421 if (rc == -ESTALE) {
2422 rcu_read_unlock();
2423 goto retry;
2424 }
2425 if (rc)
2426 goto out;
2427 } else {
2428 *out_sid = SECINITSID_PORT;
2429 }
2430
2431out:
2432 rcu_read_unlock();
2433 return rc;
2434}
2435
2436/**
2437 * security_ib_pkey_sid - Obtain the SID for a pkey.
2438 * @subnet_prefix: Subnet Prefix
2439 * @pkey_num: pkey number
2440 * @out_sid: security identifier
2441 */
2442int security_ib_pkey_sid(u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2443{
2444 struct selinux_policy *policy;
2445 struct policydb *policydb;
2446 struct sidtab *sidtab;
2447 struct ocontext *c;
2448 int rc;
2449
2450 if (!selinux_initialized()) {
2451 *out_sid = SECINITSID_UNLABELED;
2452 return 0;
2453 }
2454
2455retry:
2456 rc = 0;
2457 rcu_read_lock();
2458 policy = rcu_dereference(selinux_state.policy);
2459 policydb = &policy->policydb;
2460 sidtab = policy->sidtab;
2461
2462 c = policydb->ocontexts[OCON_IBPKEY];
2463 while (c) {
2464 if (c->u.ibpkey.low_pkey <= pkey_num &&
2465 c->u.ibpkey.high_pkey >= pkey_num &&
2466 c->u.ibpkey.subnet_prefix == subnet_prefix)
2467 break;
2468
2469 c = c->next;
2470 }
2471
2472 if (c) {
2473 rc = ocontext_to_sid(sidtab, c, 0, out_sid);
2474 if (rc == -ESTALE) {
2475 rcu_read_unlock();
2476 goto retry;
2477 }
2478 if (rc)
2479 goto out;
2480 } else
2481 *out_sid = SECINITSID_UNLABELED;
2482
2483out:
2484 rcu_read_unlock();
2485 return rc;
2486}
2487
2488/**
2489 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2490 * @dev_name: device name
2491 * @port_num: port number
2492 * @out_sid: security identifier
2493 */
2494int security_ib_endport_sid(const char *dev_name, u8 port_num, u32 *out_sid)
2495{
2496 struct selinux_policy *policy;
2497 struct policydb *policydb;
2498 struct sidtab *sidtab;
2499 struct ocontext *c;
2500 int rc;
2501
2502 if (!selinux_initialized()) {
2503 *out_sid = SECINITSID_UNLABELED;
2504 return 0;
2505 }
2506
2507retry:
2508 rc = 0;
2509 rcu_read_lock();
2510 policy = rcu_dereference(selinux_state.policy);
2511 policydb = &policy->policydb;
2512 sidtab = policy->sidtab;
2513
2514 c = policydb->ocontexts[OCON_IBENDPORT];
2515 while (c) {
2516 if (c->u.ibendport.port == port_num &&
2517 !strncmp(c->u.ibendport.dev_name,
2518 dev_name,
2519 IB_DEVICE_NAME_MAX))
2520 break;
2521
2522 c = c->next;
2523 }
2524
2525 if (c) {
2526 rc = ocontext_to_sid(sidtab, c, 0, out_sid);
2527 if (rc == -ESTALE) {
2528 rcu_read_unlock();
2529 goto retry;
2530 }
2531 if (rc)
2532 goto out;
2533 } else
2534 *out_sid = SECINITSID_UNLABELED;
2535
2536out:
2537 rcu_read_unlock();
2538 return rc;
2539}
2540
2541/**
2542 * security_netif_sid - Obtain the SID for a network interface.
2543 * @name: interface name
2544 * @if_sid: interface SID
2545 */
2546int security_netif_sid(char *name, u32 *if_sid)
2547{
2548 struct selinux_policy *policy;
2549 struct policydb *policydb;
2550 struct sidtab *sidtab;
2551 int rc;
2552 struct ocontext *c;
2553
2554 if (!selinux_initialized()) {
2555 *if_sid = SECINITSID_NETIF;
2556 return 0;
2557 }
2558
2559retry:
2560 rc = 0;
2561 rcu_read_lock();
2562 policy = rcu_dereference(selinux_state.policy);
2563 policydb = &policy->policydb;
2564 sidtab = policy->sidtab;
2565
2566 c = policydb->ocontexts[OCON_NETIF];
2567 while (c) {
2568 if (strcmp(name, c->u.name) == 0)
2569 break;
2570 c = c->next;
2571 }
2572
2573 if (c) {
2574 rc = ocontext_to_sid(sidtab, c, 0, if_sid);
2575 if (rc == -ESTALE) {
2576 rcu_read_unlock();
2577 goto retry;
2578 }
2579 if (rc)
2580 goto out;
2581 } else
2582 *if_sid = SECINITSID_NETIF;
2583
2584out:
2585 rcu_read_unlock();
2586 return rc;
2587}
2588
2589static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2590{
2591 int i, fail = 0;
2592
2593 for (i = 0; i < 4; i++)
2594 if (addr[i] != (input[i] & mask[i])) {
2595 fail = 1;
2596 break;
2597 }
2598
2599 return !fail;
2600}
2601
2602/**
2603 * security_node_sid - Obtain the SID for a node (host).
2604 * @domain: communication domain aka address family
2605 * @addrp: address
2606 * @addrlen: address length in bytes
2607 * @out_sid: security identifier
2608 */
2609int security_node_sid(u16 domain,
2610 void *addrp,
2611 u32 addrlen,
2612 u32 *out_sid)
2613{
2614 struct selinux_policy *policy;
2615 struct policydb *policydb;
2616 struct sidtab *sidtab;
2617 int rc;
2618 struct ocontext *c;
2619
2620 if (!selinux_initialized()) {
2621 *out_sid = SECINITSID_NODE;
2622 return 0;
2623 }
2624
2625retry:
2626 rcu_read_lock();
2627 policy = rcu_dereference(selinux_state.policy);
2628 policydb = &policy->policydb;
2629 sidtab = policy->sidtab;
2630
2631 switch (domain) {
2632 case AF_INET: {
2633 u32 addr;
2634
2635 rc = -EINVAL;
2636 if (addrlen != sizeof(u32))
2637 goto out;
2638
2639 addr = *((u32 *)addrp);
2640
2641 c = policydb->ocontexts[OCON_NODE];
2642 while (c) {
2643 if (c->u.node.addr == (addr & c->u.node.mask))
2644 break;
2645 c = c->next;
2646 }
2647 break;
2648 }
2649
2650 case AF_INET6:
2651 rc = -EINVAL;
2652 if (addrlen != sizeof(u64) * 2)
2653 goto out;
2654 c = policydb->ocontexts[OCON_NODE6];
2655 while (c) {
2656 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2657 c->u.node6.mask))
2658 break;
2659 c = c->next;
2660 }
2661 break;
2662
2663 default:
2664 rc = 0;
2665 *out_sid = SECINITSID_NODE;
2666 goto out;
2667 }
2668
2669 if (c) {
2670 rc = ocontext_to_sid(sidtab, c, 0, out_sid);
2671 if (rc == -ESTALE) {
2672 rcu_read_unlock();
2673 goto retry;
2674 }
2675 if (rc)
2676 goto out;
2677 } else {
2678 *out_sid = SECINITSID_NODE;
2679 }
2680
2681 rc = 0;
2682out:
2683 rcu_read_unlock();
2684 return rc;
2685}
2686
2687#define SIDS_NEL 25
2688
2689/**
2690 * security_get_user_sids - Obtain reachable SIDs for a user.
2691 * @fromsid: starting SID
2692 * @username: username
2693 * @sids: array of reachable SIDs for user
2694 * @nel: number of elements in @sids
2695 *
2696 * Generate the set of SIDs for legal security contexts
2697 * for a given user that can be reached by @fromsid.
2698 * Set *@sids to point to a dynamically allocated
2699 * array containing the set of SIDs. Set *@nel to the
2700 * number of elements in the array.
2701 */
2702
2703int security_get_user_sids(u32 fromsid,
2704 char *username,
2705 u32 **sids,
2706 u32 *nel)
2707{
2708 struct selinux_policy *policy;
2709 struct policydb *policydb;
2710 struct sidtab *sidtab;
2711 struct context *fromcon, usercon;
2712 u32 *mysids = NULL, *mysids2, sid;
2713 u32 i, j, mynel, maxnel = SIDS_NEL;
2714 struct user_datum *user;
2715 struct role_datum *role;
2716 struct ebitmap_node *rnode, *tnode;
2717 int rc;
2718
2719 *sids = NULL;
2720 *nel = 0;
2721
2722 if (!selinux_initialized())
2723 return 0;
2724
2725 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_KERNEL);
2726 if (!mysids)
2727 return -ENOMEM;
2728
2729retry:
2730 mynel = 0;
2731 rcu_read_lock();
2732 policy = rcu_dereference(selinux_state.policy);
2733 policydb = &policy->policydb;
2734 sidtab = policy->sidtab;
2735
2736 context_init(&usercon);
2737
2738 rc = -EINVAL;
2739 fromcon = sidtab_search(sidtab, fromsid);
2740 if (!fromcon)
2741 goto out_unlock;
2742
2743 rc = -EINVAL;
2744 user = symtab_search(&policydb->p_users, username);
2745 if (!user)
2746 goto out_unlock;
2747
2748 usercon.user = user->value;
2749
2750 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2751 role = policydb->role_val_to_struct[i];
2752 usercon.role = i + 1;
2753 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2754 usercon.type = j + 1;
2755
2756 if (mls_setup_user_range(policydb, fromcon, user,
2757 &usercon))
2758 continue;
2759
2760 rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2761 if (rc == -ESTALE) {
2762 rcu_read_unlock();
2763 goto retry;
2764 }
2765 if (rc)
2766 goto out_unlock;
2767 if (mynel < maxnel) {
2768 mysids[mynel++] = sid;
2769 } else {
2770 rc = -ENOMEM;
2771 maxnel += SIDS_NEL;
2772 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2773 if (!mysids2)
2774 goto out_unlock;
2775 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2776 kfree(mysids);
2777 mysids = mysids2;
2778 mysids[mynel++] = sid;
2779 }
2780 }
2781 }
2782 rc = 0;
2783out_unlock:
2784 rcu_read_unlock();
2785 if (rc || !mynel) {
2786 kfree(mysids);
2787 return rc;
2788 }
2789
2790 rc = -ENOMEM;
2791 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2792 if (!mysids2) {
2793 kfree(mysids);
2794 return rc;
2795 }
2796 for (i = 0, j = 0; i < mynel; i++) {
2797 struct av_decision dummy_avd;
2798 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2799 SECCLASS_PROCESS, /* kernel value */
2800 PROCESS__TRANSITION, AVC_STRICT,
2801 &dummy_avd);
2802 if (!rc)
2803 mysids2[j++] = mysids[i];
2804 cond_resched();
2805 }
2806 kfree(mysids);
2807 *sids = mysids2;
2808 *nel = j;
2809 return 0;
2810}
2811
2812/**
2813 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2814 * @policy: policy
2815 * @fstype: filesystem type
2816 * @path: path from root of mount
2817 * @orig_sclass: file security class
2818 * @sid: SID for path
2819 *
2820 * Obtain a SID to use for a file in a filesystem that
2821 * cannot support xattr or use a fixed labeling behavior like
2822 * transition SIDs or task SIDs.
2823 *
2824 * WARNING: This function may return -ESTALE, indicating that the caller
2825 * must retry the operation after re-acquiring the policy pointer!
2826 */
2827static inline int __security_genfs_sid(struct selinux_policy *policy,
2828 const char *fstype,
2829 const char *path,
2830 u16 orig_sclass,
2831 u32 *sid)
2832{
2833 struct policydb *policydb = &policy->policydb;
2834 struct sidtab *sidtab = policy->sidtab;
2835 u16 sclass;
2836 struct genfs *genfs;
2837 struct ocontext *c;
2838 int cmp = 0;
2839
2840 while (path[0] == '/' && path[1] == '/')
2841 path++;
2842
2843 sclass = unmap_class(&policy->map, orig_sclass);
2844 *sid = SECINITSID_UNLABELED;
2845
2846 for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2847 cmp = strcmp(fstype, genfs->fstype);
2848 if (cmp <= 0)
2849 break;
2850 }
2851
2852 if (!genfs || cmp)
2853 return -ENOENT;
2854
2855 for (c = genfs->head; c; c = c->next) {
2856 size_t len = strlen(c->u.name);
2857 if ((!c->v.sclass || sclass == c->v.sclass) &&
2858 (strncmp(c->u.name, path, len) == 0))
2859 break;
2860 }
2861
2862 if (!c)
2863 return -ENOENT;
2864
2865 return ocontext_to_sid(sidtab, c, 0, sid);
2866}
2867
2868/**
2869 * security_genfs_sid - Obtain a SID for a file in a filesystem
2870 * @fstype: filesystem type
2871 * @path: path from root of mount
2872 * @orig_sclass: file security class
2873 * @sid: SID for path
2874 *
2875 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2876 * it afterward.
2877 */
2878int security_genfs_sid(const char *fstype,
2879 const char *path,
2880 u16 orig_sclass,
2881 u32 *sid)
2882{
2883 struct selinux_policy *policy;
2884 int retval;
2885
2886 if (!selinux_initialized()) {
2887 *sid = SECINITSID_UNLABELED;
2888 return 0;
2889 }
2890
2891 do {
2892 rcu_read_lock();
2893 policy = rcu_dereference(selinux_state.policy);
2894 retval = __security_genfs_sid(policy, fstype, path,
2895 orig_sclass, sid);
2896 rcu_read_unlock();
2897 } while (retval == -ESTALE);
2898 return retval;
2899}
2900
2901int selinux_policy_genfs_sid(struct selinux_policy *policy,
2902 const char *fstype,
2903 const char *path,
2904 u16 orig_sclass,
2905 u32 *sid)
2906{
2907 /* no lock required, policy is not yet accessible by other threads */
2908 return __security_genfs_sid(policy, fstype, path, orig_sclass, sid);
2909}
2910
2911/**
2912 * security_fs_use - Determine how to handle labeling for a filesystem.
2913 * @sb: superblock in question
2914 */
2915int security_fs_use(struct super_block *sb)
2916{
2917 struct selinux_policy *policy;
2918 struct policydb *policydb;
2919 struct sidtab *sidtab;
2920 int rc;
2921 struct ocontext *c;
2922 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2923 const char *fstype = sb->s_type->name;
2924
2925 if (!selinux_initialized()) {
2926 sbsec->behavior = SECURITY_FS_USE_NONE;
2927 sbsec->sid = SECINITSID_UNLABELED;
2928 return 0;
2929 }
2930
2931retry:
2932 rcu_read_lock();
2933 policy = rcu_dereference(selinux_state.policy);
2934 policydb = &policy->policydb;
2935 sidtab = policy->sidtab;
2936
2937 c = policydb->ocontexts[OCON_FSUSE];
2938 while (c) {
2939 if (strcmp(fstype, c->u.name) == 0)
2940 break;
2941 c = c->next;
2942 }
2943
2944 if (c) {
2945 sbsec->behavior = c->v.behavior;
2946 rc = ocontext_to_sid(sidtab, c, 0, &sbsec->sid);
2947 if (rc == -ESTALE) {
2948 rcu_read_unlock();
2949 goto retry;
2950 }
2951 if (rc)
2952 goto out;
2953 } else {
2954 rc = __security_genfs_sid(policy, fstype, "/",
2955 SECCLASS_DIR, &sbsec->sid);
2956 if (rc == -ESTALE) {
2957 rcu_read_unlock();
2958 goto retry;
2959 }
2960 if (rc) {
2961 sbsec->behavior = SECURITY_FS_USE_NONE;
2962 rc = 0;
2963 } else {
2964 sbsec->behavior = SECURITY_FS_USE_GENFS;
2965 }
2966 }
2967
2968out:
2969 rcu_read_unlock();
2970 return rc;
2971}
2972
2973int security_get_bools(struct selinux_policy *policy,
2974 u32 *len, char ***names, int **values)
2975{
2976 struct policydb *policydb;
2977 u32 i;
2978 int rc;
2979
2980 policydb = &policy->policydb;
2981
2982 *names = NULL;
2983 *values = NULL;
2984
2985 rc = 0;
2986 *len = policydb->p_bools.nprim;
2987 if (!*len)
2988 goto out;
2989
2990 rc = -ENOMEM;
2991 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2992 if (!*names)
2993 goto err;
2994
2995 rc = -ENOMEM;
2996 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2997 if (!*values)
2998 goto err;
2999
3000 for (i = 0; i < *len; i++) {
3001 (*values)[i] = policydb->bool_val_to_struct[i]->state;
3002
3003 rc = -ENOMEM;
3004 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
3005 GFP_ATOMIC);
3006 if (!(*names)[i])
3007 goto err;
3008 }
3009 rc = 0;
3010out:
3011 return rc;
3012err:
3013 if (*names) {
3014 for (i = 0; i < *len; i++)
3015 kfree((*names)[i]);
3016 kfree(*names);
3017 }
3018 kfree(*values);
3019 *len = 0;
3020 *names = NULL;
3021 *values = NULL;
3022 goto out;
3023}
3024
3025
3026int security_set_bools(u32 len, int *values)
3027{
3028 struct selinux_state *state = &selinux_state;
3029 struct selinux_policy *newpolicy, *oldpolicy;
3030 int rc;
3031 u32 i, seqno = 0;
3032
3033 if (!selinux_initialized())
3034 return -EINVAL;
3035
3036 oldpolicy = rcu_dereference_protected(state->policy,
3037 lockdep_is_held(&state->policy_mutex));
3038
3039 /* Consistency check on number of booleans, should never fail */
3040 if (WARN_ON(len != oldpolicy->policydb.p_bools.nprim))
3041 return -EINVAL;
3042
3043 newpolicy = kmemdup(oldpolicy, sizeof(*newpolicy), GFP_KERNEL);
3044 if (!newpolicy)
3045 return -ENOMEM;
3046
3047 /*
3048 * Deep copy only the parts of the policydb that might be
3049 * modified as a result of changing booleans.
3050 */
3051 rc = cond_policydb_dup(&newpolicy->policydb, &oldpolicy->policydb);
3052 if (rc) {
3053 kfree(newpolicy);
3054 return -ENOMEM;
3055 }
3056
3057 /* Update the boolean states in the copy */
3058 for (i = 0; i < len; i++) {
3059 int new_state = !!values[i];
3060 int old_state = newpolicy->policydb.bool_val_to_struct[i]->state;
3061
3062 if (new_state != old_state) {
3063 audit_log(audit_context(), GFP_ATOMIC,
3064 AUDIT_MAC_CONFIG_CHANGE,
3065 "bool=%s val=%d old_val=%d auid=%u ses=%u",
3066 sym_name(&newpolicy->policydb, SYM_BOOLS, i),
3067 new_state,
3068 old_state,
3069 from_kuid(&init_user_ns, audit_get_loginuid(current)),
3070 audit_get_sessionid(current));
3071 newpolicy->policydb.bool_val_to_struct[i]->state = new_state;
3072 }
3073 }
3074
3075 /* Re-evaluate the conditional rules in the copy */
3076 evaluate_cond_nodes(&newpolicy->policydb);
3077
3078 /* Set latest granting seqno for new policy */
3079 newpolicy->latest_granting = oldpolicy->latest_granting + 1;
3080 seqno = newpolicy->latest_granting;
3081
3082 /* Install the new policy */
3083 rcu_assign_pointer(state->policy, newpolicy);
3084
3085 /*
3086 * Free the conditional portions of the old policydb
3087 * that were copied for the new policy, and the oldpolicy
3088 * structure itself but not what it references.
3089 */
3090 synchronize_rcu();
3091 selinux_policy_cond_free(oldpolicy);
3092
3093 /* Notify others of the policy change */
3094 selinux_notify_policy_change(seqno);
3095 return 0;
3096}
3097
3098int security_get_bool_value(u32 index)
3099{
3100 struct selinux_policy *policy;
3101 struct policydb *policydb;
3102 int rc;
3103 u32 len;
3104
3105 if (!selinux_initialized())
3106 return 0;
3107
3108 rcu_read_lock();
3109 policy = rcu_dereference(selinux_state.policy);
3110 policydb = &policy->policydb;
3111
3112 rc = -EFAULT;
3113 len = policydb->p_bools.nprim;
3114 if (index >= len)
3115 goto out;
3116
3117 rc = policydb->bool_val_to_struct[index]->state;
3118out:
3119 rcu_read_unlock();
3120 return rc;
3121}
3122
3123static int security_preserve_bools(struct selinux_policy *oldpolicy,
3124 struct selinux_policy *newpolicy)
3125{
3126 int rc, *bvalues = NULL;
3127 char **bnames = NULL;
3128 struct cond_bool_datum *booldatum;
3129 u32 i, nbools = 0;
3130
3131 rc = security_get_bools(oldpolicy, &nbools, &bnames, &bvalues);
3132 if (rc)
3133 goto out;
3134 for (i = 0; i < nbools; i++) {
3135 booldatum = symtab_search(&newpolicy->policydb.p_bools,
3136 bnames[i]);
3137 if (booldatum)
3138 booldatum->state = bvalues[i];
3139 }
3140 evaluate_cond_nodes(&newpolicy->policydb);
3141
3142out:
3143 if (bnames) {
3144 for (i = 0; i < nbools; i++)
3145 kfree(bnames[i]);
3146 }
3147 kfree(bnames);
3148 kfree(bvalues);
3149 return rc;
3150}
3151
3152/*
3153 * security_sid_mls_copy() - computes a new sid based on the given
3154 * sid and the mls portion of mls_sid.
3155 */
3156int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
3157{
3158 struct selinux_policy *policy;
3159 struct policydb *policydb;
3160 struct sidtab *sidtab;
3161 struct context *context1;
3162 struct context *context2;
3163 struct context newcon;
3164 char *s;
3165 u32 len;
3166 int rc;
3167
3168 if (!selinux_initialized()) {
3169 *new_sid = sid;
3170 return 0;
3171 }
3172
3173retry:
3174 rc = 0;
3175 context_init(&newcon);
3176
3177 rcu_read_lock();
3178 policy = rcu_dereference(selinux_state.policy);
3179 policydb = &policy->policydb;
3180 sidtab = policy->sidtab;
3181
3182 if (!policydb->mls_enabled) {
3183 *new_sid = sid;
3184 goto out_unlock;
3185 }
3186
3187 rc = -EINVAL;
3188 context1 = sidtab_search(sidtab, sid);
3189 if (!context1) {
3190 pr_err("SELinux: %s: unrecognized SID %d\n",
3191 __func__, sid);
3192 goto out_unlock;
3193 }
3194
3195 rc = -EINVAL;
3196 context2 = sidtab_search(sidtab, mls_sid);
3197 if (!context2) {
3198 pr_err("SELinux: %s: unrecognized SID %d\n",
3199 __func__, mls_sid);
3200 goto out_unlock;
3201 }
3202
3203 newcon.user = context1->user;
3204 newcon.role = context1->role;
3205 newcon.type = context1->type;
3206 rc = mls_context_cpy(&newcon, context2);
3207 if (rc)
3208 goto out_unlock;
3209
3210 /* Check the validity of the new context. */
3211 if (!policydb_context_isvalid(policydb, &newcon)) {
3212 rc = convert_context_handle_invalid_context(policydb,
3213 &newcon);
3214 if (rc) {
3215 if (!context_struct_to_string(policydb, &newcon, &s,
3216 &len)) {
3217 struct audit_buffer *ab;
3218
3219 ab = audit_log_start(audit_context(),
3220 GFP_ATOMIC,
3221 AUDIT_SELINUX_ERR);
3222 audit_log_format(ab,
3223 "op=security_sid_mls_copy invalid_context=");
3224 /* don't record NUL with untrusted strings */
3225 audit_log_n_untrustedstring(ab, s, len - 1);
3226 audit_log_end(ab);
3227 kfree(s);
3228 }
3229 goto out_unlock;
3230 }
3231 }
3232 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3233 if (rc == -ESTALE) {
3234 rcu_read_unlock();
3235 context_destroy(&newcon);
3236 goto retry;
3237 }
3238out_unlock:
3239 rcu_read_unlock();
3240 context_destroy(&newcon);
3241 return rc;
3242}
3243
3244/**
3245 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3246 * @nlbl_sid: NetLabel SID
3247 * @nlbl_type: NetLabel labeling protocol type
3248 * @xfrm_sid: XFRM SID
3249 * @peer_sid: network peer sid
3250 *
3251 * Description:
3252 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3253 * resolved into a single SID it is returned via @peer_sid and the function
3254 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3255 * returns a negative value. A table summarizing the behavior is below:
3256 *
3257 * | function return | @sid
3258 * ------------------------------+-----------------+-----------------
3259 * no peer labels | 0 | SECSID_NULL
3260 * single peer label | 0 | <peer_label>
3261 * multiple, consistent labels | 0 | <peer_label>
3262 * multiple, inconsistent labels | -<errno> | SECSID_NULL
3263 *
3264 */
3265int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
3266 u32 xfrm_sid,
3267 u32 *peer_sid)
3268{
3269 struct selinux_policy *policy;
3270 struct policydb *policydb;
3271 struct sidtab *sidtab;
3272 int rc;
3273 struct context *nlbl_ctx;
3274 struct context *xfrm_ctx;
3275
3276 *peer_sid = SECSID_NULL;
3277
3278 /* handle the common (which also happens to be the set of easy) cases
3279 * right away, these two if statements catch everything involving a
3280 * single or absent peer SID/label */
3281 if (xfrm_sid == SECSID_NULL) {
3282 *peer_sid = nlbl_sid;
3283 return 0;
3284 }
3285 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3286 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3287 * is present */
3288 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3289 *peer_sid = xfrm_sid;
3290 return 0;
3291 }
3292
3293 if (!selinux_initialized())
3294 return 0;
3295
3296 rcu_read_lock();
3297 policy = rcu_dereference(selinux_state.policy);
3298 policydb = &policy->policydb;
3299 sidtab = policy->sidtab;
3300
3301 /*
3302 * We don't need to check initialized here since the only way both
3303 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3304 * security server was initialized and state->initialized was true.
3305 */
3306 if (!policydb->mls_enabled) {
3307 rc = 0;
3308 goto out;
3309 }
3310
3311 rc = -EINVAL;
3312 nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3313 if (!nlbl_ctx) {
3314 pr_err("SELinux: %s: unrecognized SID %d\n",
3315 __func__, nlbl_sid);
3316 goto out;
3317 }
3318 rc = -EINVAL;
3319 xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3320 if (!xfrm_ctx) {
3321 pr_err("SELinux: %s: unrecognized SID %d\n",
3322 __func__, xfrm_sid);
3323 goto out;
3324 }
3325 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3326 if (rc)
3327 goto out;
3328
3329 /* at present NetLabel SIDs/labels really only carry MLS
3330 * information so if the MLS portion of the NetLabel SID
3331 * matches the MLS portion of the labeled XFRM SID/label
3332 * then pass along the XFRM SID as it is the most
3333 * expressive */
3334 *peer_sid = xfrm_sid;
3335out:
3336 rcu_read_unlock();
3337 return rc;
3338}
3339
3340static int get_classes_callback(void *k, void *d, void *args)
3341{
3342 struct class_datum *datum = d;
3343 char *name = k, **classes = args;
3344 u32 value = datum->value - 1;
3345
3346 classes[value] = kstrdup(name, GFP_ATOMIC);
3347 if (!classes[value])
3348 return -ENOMEM;
3349
3350 return 0;
3351}
3352
3353int security_get_classes(struct selinux_policy *policy,
3354 char ***classes, u32 *nclasses)
3355{
3356 struct policydb *policydb;
3357 int rc;
3358
3359 policydb = &policy->policydb;
3360
3361 rc = -ENOMEM;
3362 *nclasses = policydb->p_classes.nprim;
3363 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3364 if (!*classes)
3365 goto out;
3366
3367 rc = hashtab_map(&policydb->p_classes.table, get_classes_callback,
3368 *classes);
3369 if (rc) {
3370 u32 i;
3371
3372 for (i = 0; i < *nclasses; i++)
3373 kfree((*classes)[i]);
3374 kfree(*classes);
3375 }
3376
3377out:
3378 return rc;
3379}
3380
3381static int get_permissions_callback(void *k, void *d, void *args)
3382{
3383 struct perm_datum *datum = d;
3384 char *name = k, **perms = args;
3385 u32 value = datum->value - 1;
3386
3387 perms[value] = kstrdup(name, GFP_ATOMIC);
3388 if (!perms[value])
3389 return -ENOMEM;
3390
3391 return 0;
3392}
3393
3394int security_get_permissions(struct selinux_policy *policy,
3395 const char *class, char ***perms, u32 *nperms)
3396{
3397 struct policydb *policydb;
3398 u32 i;
3399 int rc;
3400 struct class_datum *match;
3401
3402 policydb = &policy->policydb;
3403
3404 rc = -EINVAL;
3405 match = symtab_search(&policydb->p_classes, class);
3406 if (!match) {
3407 pr_err("SELinux: %s: unrecognized class %s\n",
3408 __func__, class);
3409 goto out;
3410 }
3411
3412 rc = -ENOMEM;
3413 *nperms = match->permissions.nprim;
3414 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3415 if (!*perms)
3416 goto out;
3417
3418 if (match->comdatum) {
3419 rc = hashtab_map(&match->comdatum->permissions.table,
3420 get_permissions_callback, *perms);
3421 if (rc)
3422 goto err;
3423 }
3424
3425 rc = hashtab_map(&match->permissions.table, get_permissions_callback,
3426 *perms);
3427 if (rc)
3428 goto err;
3429
3430out:
3431 return rc;
3432
3433err:
3434 for (i = 0; i < *nperms; i++)
3435 kfree((*perms)[i]);
3436 kfree(*perms);
3437 return rc;
3438}
3439
3440int security_get_reject_unknown(void)
3441{
3442 struct selinux_policy *policy;
3443 int value;
3444
3445 if (!selinux_initialized())
3446 return 0;
3447
3448 rcu_read_lock();
3449 policy = rcu_dereference(selinux_state.policy);
3450 value = policy->policydb.reject_unknown;
3451 rcu_read_unlock();
3452 return value;
3453}
3454
3455int security_get_allow_unknown(void)
3456{
3457 struct selinux_policy *policy;
3458 int value;
3459
3460 if (!selinux_initialized())
3461 return 0;
3462
3463 rcu_read_lock();
3464 policy = rcu_dereference(selinux_state.policy);
3465 value = policy->policydb.allow_unknown;
3466 rcu_read_unlock();
3467 return value;
3468}
3469
3470/**
3471 * security_policycap_supported - Check for a specific policy capability
3472 * @req_cap: capability
3473 *
3474 * Description:
3475 * This function queries the currently loaded policy to see if it supports the
3476 * capability specified by @req_cap. Returns true (1) if the capability is
3477 * supported, false (0) if it isn't supported.
3478 *
3479 */
3480int security_policycap_supported(unsigned int req_cap)
3481{
3482 struct selinux_policy *policy;
3483 int rc;
3484
3485 if (!selinux_initialized())
3486 return 0;
3487
3488 rcu_read_lock();
3489 policy = rcu_dereference(selinux_state.policy);
3490 rc = ebitmap_get_bit(&policy->policydb.policycaps, req_cap);
3491 rcu_read_unlock();
3492
3493 return rc;
3494}
3495
3496struct selinux_audit_rule {
3497 u32 au_seqno;
3498 struct context au_ctxt;
3499};
3500
3501void selinux_audit_rule_free(void *vrule)
3502{
3503 struct selinux_audit_rule *rule = vrule;
3504
3505 if (rule) {
3506 context_destroy(&rule->au_ctxt);
3507 kfree(rule);
3508 }
3509}
3510
3511int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3512{
3513 struct selinux_state *state = &selinux_state;
3514 struct selinux_policy *policy;
3515 struct policydb *policydb;
3516 struct selinux_audit_rule *tmprule;
3517 struct role_datum *roledatum;
3518 struct type_datum *typedatum;
3519 struct user_datum *userdatum;
3520 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3521 int rc = 0;
3522
3523 *rule = NULL;
3524
3525 if (!selinux_initialized())
3526 return -EOPNOTSUPP;
3527
3528 switch (field) {
3529 case AUDIT_SUBJ_USER:
3530 case AUDIT_SUBJ_ROLE:
3531 case AUDIT_SUBJ_TYPE:
3532 case AUDIT_OBJ_USER:
3533 case AUDIT_OBJ_ROLE:
3534 case AUDIT_OBJ_TYPE:
3535 /* only 'equals' and 'not equals' fit user, role, and type */
3536 if (op != Audit_equal && op != Audit_not_equal)
3537 return -EINVAL;
3538 break;
3539 case AUDIT_SUBJ_SEN:
3540 case AUDIT_SUBJ_CLR:
3541 case AUDIT_OBJ_LEV_LOW:
3542 case AUDIT_OBJ_LEV_HIGH:
3543 /* we do not allow a range, indicated by the presence of '-' */
3544 if (strchr(rulestr, '-'))
3545 return -EINVAL;
3546 break;
3547 default:
3548 /* only the above fields are valid */
3549 return -EINVAL;
3550 }
3551
3552 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3553 if (!tmprule)
3554 return -ENOMEM;
3555 context_init(&tmprule->au_ctxt);
3556
3557 rcu_read_lock();
3558 policy = rcu_dereference(state->policy);
3559 policydb = &policy->policydb;
3560 tmprule->au_seqno = policy->latest_granting;
3561 switch (field) {
3562 case AUDIT_SUBJ_USER:
3563 case AUDIT_OBJ_USER:
3564 userdatum = symtab_search(&policydb->p_users, rulestr);
3565 if (!userdatum) {
3566 rc = -EINVAL;
3567 goto err;
3568 }
3569 tmprule->au_ctxt.user = userdatum->value;
3570 break;
3571 case AUDIT_SUBJ_ROLE:
3572 case AUDIT_OBJ_ROLE:
3573 roledatum = symtab_search(&policydb->p_roles, rulestr);
3574 if (!roledatum) {
3575 rc = -EINVAL;
3576 goto err;
3577 }
3578 tmprule->au_ctxt.role = roledatum->value;
3579 break;
3580 case AUDIT_SUBJ_TYPE:
3581 case AUDIT_OBJ_TYPE:
3582 typedatum = symtab_search(&policydb->p_types, rulestr);
3583 if (!typedatum) {
3584 rc = -EINVAL;
3585 goto err;
3586 }
3587 tmprule->au_ctxt.type = typedatum->value;
3588 break;
3589 case AUDIT_SUBJ_SEN:
3590 case AUDIT_SUBJ_CLR:
3591 case AUDIT_OBJ_LEV_LOW:
3592 case AUDIT_OBJ_LEV_HIGH:
3593 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3594 GFP_ATOMIC);
3595 if (rc)
3596 goto err;
3597 break;
3598 }
3599 rcu_read_unlock();
3600
3601 *rule = tmprule;
3602 return 0;
3603
3604err:
3605 rcu_read_unlock();
3606 selinux_audit_rule_free(tmprule);
3607 *rule = NULL;
3608 return rc;
3609}
3610
3611/* Check to see if the rule contains any selinux fields */
3612int selinux_audit_rule_known(struct audit_krule *rule)
3613{
3614 u32 i;
3615
3616 for (i = 0; i < rule->field_count; i++) {
3617 struct audit_field *f = &rule->fields[i];
3618 switch (f->type) {
3619 case AUDIT_SUBJ_USER:
3620 case AUDIT_SUBJ_ROLE:
3621 case AUDIT_SUBJ_TYPE:
3622 case AUDIT_SUBJ_SEN:
3623 case AUDIT_SUBJ_CLR:
3624 case AUDIT_OBJ_USER:
3625 case AUDIT_OBJ_ROLE:
3626 case AUDIT_OBJ_TYPE:
3627 case AUDIT_OBJ_LEV_LOW:
3628 case AUDIT_OBJ_LEV_HIGH:
3629 return 1;
3630 }
3631 }
3632
3633 return 0;
3634}
3635
3636int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule)
3637{
3638 struct selinux_state *state = &selinux_state;
3639 struct selinux_policy *policy;
3640 struct context *ctxt;
3641 struct mls_level *level;
3642 struct selinux_audit_rule *rule = vrule;
3643 int match = 0;
3644
3645 if (unlikely(!rule)) {
3646 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3647 return -ENOENT;
3648 }
3649
3650 if (!selinux_initialized())
3651 return 0;
3652
3653 rcu_read_lock();
3654
3655 policy = rcu_dereference(state->policy);
3656
3657 if (rule->au_seqno < policy->latest_granting) {
3658 match = -ESTALE;
3659 goto out;
3660 }
3661
3662 ctxt = sidtab_search(policy->sidtab, sid);
3663 if (unlikely(!ctxt)) {
3664 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3665 sid);
3666 match = -ENOENT;
3667 goto out;
3668 }
3669
3670 /* a field/op pair that is not caught here will simply fall through
3671 without a match */
3672 switch (field) {
3673 case AUDIT_SUBJ_USER:
3674 case AUDIT_OBJ_USER:
3675 switch (op) {
3676 case Audit_equal:
3677 match = (ctxt->user == rule->au_ctxt.user);
3678 break;
3679 case Audit_not_equal:
3680 match = (ctxt->user != rule->au_ctxt.user);
3681 break;
3682 }
3683 break;
3684 case AUDIT_SUBJ_ROLE:
3685 case AUDIT_OBJ_ROLE:
3686 switch (op) {
3687 case Audit_equal:
3688 match = (ctxt->role == rule->au_ctxt.role);
3689 break;
3690 case Audit_not_equal:
3691 match = (ctxt->role != rule->au_ctxt.role);
3692 break;
3693 }
3694 break;
3695 case AUDIT_SUBJ_TYPE:
3696 case AUDIT_OBJ_TYPE:
3697 switch (op) {
3698 case Audit_equal:
3699 match = (ctxt->type == rule->au_ctxt.type);
3700 break;
3701 case Audit_not_equal:
3702 match = (ctxt->type != rule->au_ctxt.type);
3703 break;
3704 }
3705 break;
3706 case AUDIT_SUBJ_SEN:
3707 case AUDIT_SUBJ_CLR:
3708 case AUDIT_OBJ_LEV_LOW:
3709 case AUDIT_OBJ_LEV_HIGH:
3710 level = ((field == AUDIT_SUBJ_SEN ||
3711 field == AUDIT_OBJ_LEV_LOW) ?
3712 &ctxt->range.level[0] : &ctxt->range.level[1]);
3713 switch (op) {
3714 case Audit_equal:
3715 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3716 level);
3717 break;
3718 case Audit_not_equal:
3719 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3720 level);
3721 break;
3722 case Audit_lt:
3723 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3724 level) &&
3725 !mls_level_eq(&rule->au_ctxt.range.level[0],
3726 level));
3727 break;
3728 case Audit_le:
3729 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3730 level);
3731 break;
3732 case Audit_gt:
3733 match = (mls_level_dom(level,
3734 &rule->au_ctxt.range.level[0]) &&
3735 !mls_level_eq(level,
3736 &rule->au_ctxt.range.level[0]));
3737 break;
3738 case Audit_ge:
3739 match = mls_level_dom(level,
3740 &rule->au_ctxt.range.level[0]);
3741 break;
3742 }
3743 }
3744
3745out:
3746 rcu_read_unlock();
3747 return match;
3748}
3749
3750static int aurule_avc_callback(u32 event)
3751{
3752 if (event == AVC_CALLBACK_RESET)
3753 return audit_update_lsm_rules();
3754 return 0;
3755}
3756
3757static int __init aurule_init(void)
3758{
3759 int err;
3760
3761 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3762 if (err)
3763 panic("avc_add_callback() failed, error %d\n", err);
3764
3765 return err;
3766}
3767__initcall(aurule_init);
3768
3769#ifdef CONFIG_NETLABEL
3770/**
3771 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3772 * @secattr: the NetLabel packet security attributes
3773 * @sid: the SELinux SID
3774 *
3775 * Description:
3776 * Attempt to cache the context in @ctx, which was derived from the packet in
3777 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3778 * already been initialized.
3779 *
3780 */
3781static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3782 u32 sid)
3783{
3784 u32 *sid_cache;
3785
3786 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3787 if (sid_cache == NULL)
3788 return;
3789 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3790 if (secattr->cache == NULL) {
3791 kfree(sid_cache);
3792 return;
3793 }
3794
3795 *sid_cache = sid;
3796 secattr->cache->free = kfree;
3797 secattr->cache->data = sid_cache;
3798 secattr->flags |= NETLBL_SECATTR_CACHE;
3799}
3800
3801/**
3802 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3803 * @secattr: the NetLabel packet security attributes
3804 * @sid: the SELinux SID
3805 *
3806 * Description:
3807 * Convert the given NetLabel security attributes in @secattr into a
3808 * SELinux SID. If the @secattr field does not contain a full SELinux
3809 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3810 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3811 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3812 * conversion for future lookups. Returns zero on success, negative values on
3813 * failure.
3814 *
3815 */
3816int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3817 u32 *sid)
3818{
3819 struct selinux_policy *policy;
3820 struct policydb *policydb;
3821 struct sidtab *sidtab;
3822 int rc;
3823 struct context *ctx;
3824 struct context ctx_new;
3825
3826 if (!selinux_initialized()) {
3827 *sid = SECSID_NULL;
3828 return 0;
3829 }
3830
3831retry:
3832 rc = 0;
3833 rcu_read_lock();
3834 policy = rcu_dereference(selinux_state.policy);
3835 policydb = &policy->policydb;
3836 sidtab = policy->sidtab;
3837
3838 if (secattr->flags & NETLBL_SECATTR_CACHE)
3839 *sid = *(u32 *)secattr->cache->data;
3840 else if (secattr->flags & NETLBL_SECATTR_SECID)
3841 *sid = secattr->attr.secid;
3842 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3843 rc = -EIDRM;
3844 ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3845 if (ctx == NULL)
3846 goto out;
3847
3848 context_init(&ctx_new);
3849 ctx_new.user = ctx->user;
3850 ctx_new.role = ctx->role;
3851 ctx_new.type = ctx->type;
3852 mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3853 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3854 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3855 if (rc)
3856 goto out;
3857 }
3858 rc = -EIDRM;
3859 if (!mls_context_isvalid(policydb, &ctx_new)) {
3860 ebitmap_destroy(&ctx_new.range.level[0].cat);
3861 goto out;
3862 }
3863
3864 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3865 ebitmap_destroy(&ctx_new.range.level[0].cat);
3866 if (rc == -ESTALE) {
3867 rcu_read_unlock();
3868 goto retry;
3869 }
3870 if (rc)
3871 goto out;
3872
3873 security_netlbl_cache_add(secattr, *sid);
3874 } else
3875 *sid = SECSID_NULL;
3876
3877out:
3878 rcu_read_unlock();
3879 return rc;
3880}
3881
3882/**
3883 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3884 * @sid: the SELinux SID
3885 * @secattr: the NetLabel packet security attributes
3886 *
3887 * Description:
3888 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3889 * Returns zero on success, negative values on failure.
3890 *
3891 */
3892int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3893{
3894 struct selinux_policy *policy;
3895 struct policydb *policydb;
3896 int rc;
3897 struct context *ctx;
3898
3899 if (!selinux_initialized())
3900 return 0;
3901
3902 rcu_read_lock();
3903 policy = rcu_dereference(selinux_state.policy);
3904 policydb = &policy->policydb;
3905
3906 rc = -ENOENT;
3907 ctx = sidtab_search(policy->sidtab, sid);
3908 if (ctx == NULL)
3909 goto out;
3910
3911 rc = -ENOMEM;
3912 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3913 GFP_ATOMIC);
3914 if (secattr->domain == NULL)
3915 goto out;
3916
3917 secattr->attr.secid = sid;
3918 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3919 mls_export_netlbl_lvl(policydb, ctx, secattr);
3920 rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3921out:
3922 rcu_read_unlock();
3923 return rc;
3924}
3925#endif /* CONFIG_NETLABEL */
3926
3927/**
3928 * __security_read_policy - read the policy.
3929 * @policy: SELinux policy
3930 * @data: binary policy data
3931 * @len: length of data in bytes
3932 *
3933 */
3934static int __security_read_policy(struct selinux_policy *policy,
3935 void *data, size_t *len)
3936{
3937 int rc;
3938 struct policy_file fp;
3939
3940 fp.data = data;
3941 fp.len = *len;
3942
3943 rc = policydb_write(&policy->policydb, &fp);
3944 if (rc)
3945 return rc;
3946
3947 *len = (unsigned long)fp.data - (unsigned long)data;
3948 return 0;
3949}
3950
3951/**
3952 * security_read_policy - read the policy.
3953 * @data: binary policy data
3954 * @len: length of data in bytes
3955 *
3956 */
3957int security_read_policy(void **data, size_t *len)
3958{
3959 struct selinux_state *state = &selinux_state;
3960 struct selinux_policy *policy;
3961
3962 policy = rcu_dereference_protected(
3963 state->policy, lockdep_is_held(&state->policy_mutex));
3964 if (!policy)
3965 return -EINVAL;
3966
3967 *len = policy->policydb.len;
3968 *data = vmalloc_user(*len);
3969 if (!*data)
3970 return -ENOMEM;
3971
3972 return __security_read_policy(policy, *data, len);
3973}
3974
3975/**
3976 * security_read_state_kernel - read the policy.
3977 * @data: binary policy data
3978 * @len: length of data in bytes
3979 *
3980 * Allocates kernel memory for reading SELinux policy.
3981 * This function is for internal use only and should not
3982 * be used for returning data to user space.
3983 *
3984 * This function must be called with policy_mutex held.
3985 */
3986int security_read_state_kernel(void **data, size_t *len)
3987{
3988 int err;
3989 struct selinux_state *state = &selinux_state;
3990 struct selinux_policy *policy;
3991
3992 policy = rcu_dereference_protected(
3993 state->policy, lockdep_is_held(&state->policy_mutex));
3994 if (!policy)
3995 return -EINVAL;
3996
3997 *len = policy->policydb.len;
3998 *data = vmalloc(*len);
3999 if (!*data)
4000 return -ENOMEM;
4001
4002 err = __security_read_policy(policy, *data, len);
4003 if (err) {
4004 vfree(*data);
4005 *data = NULL;
4006 *len = 0;
4007 }
4008 return err;
4009}