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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 and which base permissions are covered.
586 */
587void services_compute_xperms_drivers(
588 struct extended_perms *xperms,
589 struct avtab_node *node)
590{
591 unsigned int i;
592
593 switch (node->datum.u.xperms->specified) {
594 case AVTAB_XPERMS_IOCTLDRIVER:
595 xperms->base_perms |= AVC_EXT_IOCTL;
596 /* if one or more driver has all permissions allowed */
597 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
598 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
599 break;
600 case AVTAB_XPERMS_IOCTLFUNCTION:
601 xperms->base_perms |= AVC_EXT_IOCTL;
602 /* if allowing permissions within a driver */
603 security_xperm_set(xperms->drivers.p,
604 node->datum.u.xperms->driver);
605 break;
606 case AVTAB_XPERMS_NLMSG:
607 xperms->base_perms |= AVC_EXT_NLMSG;
608 /* if allowing permissions within a driver */
609 security_xperm_set(xperms->drivers.p,
610 node->datum.u.xperms->driver);
611 break;
612 }
613
614 xperms->len = 1;
615}
616
617/*
618 * Compute access vectors and extended permissions based on a context
619 * structure pair for the permissions in a particular class.
620 */
621static void context_struct_compute_av(struct policydb *policydb,
622 struct context *scontext,
623 struct context *tcontext,
624 u16 tclass,
625 struct av_decision *avd,
626 struct extended_perms *xperms)
627{
628 struct constraint_node *constraint;
629 struct role_allow *ra;
630 struct avtab_key avkey;
631 struct avtab_node *node;
632 struct class_datum *tclass_datum;
633 struct ebitmap *sattr, *tattr;
634 struct ebitmap_node *snode, *tnode;
635 unsigned int i, j;
636
637 avd->allowed = 0;
638 avd->auditallow = 0;
639 avd->auditdeny = 0xffffffff;
640 if (xperms) {
641 memset(xperms, 0, sizeof(*xperms));
642 }
643
644 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
645 pr_warn_ratelimited("SELinux: Invalid class %u\n", tclass);
646 return;
647 }
648
649 tclass_datum = policydb->class_val_to_struct[tclass - 1];
650
651 /*
652 * If a specific type enforcement rule was defined for
653 * this permission check, then use it.
654 */
655 avkey.target_class = tclass;
656 avkey.specified = AVTAB_AV | AVTAB_XPERMS;
657 sattr = &policydb->type_attr_map_array[scontext->type - 1];
658 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
659 ebitmap_for_each_positive_bit(sattr, snode, i) {
660 ebitmap_for_each_positive_bit(tattr, tnode, j) {
661 avkey.source_type = i + 1;
662 avkey.target_type = j + 1;
663 for (node = avtab_search_node(&policydb->te_avtab,
664 &avkey);
665 node;
666 node = avtab_search_node_next(node, avkey.specified)) {
667 if (node->key.specified == AVTAB_ALLOWED)
668 avd->allowed |= node->datum.u.data;
669 else if (node->key.specified == AVTAB_AUDITALLOW)
670 avd->auditallow |= node->datum.u.data;
671 else if (node->key.specified == AVTAB_AUDITDENY)
672 avd->auditdeny &= node->datum.u.data;
673 else if (xperms && (node->key.specified & AVTAB_XPERMS))
674 services_compute_xperms_drivers(xperms, node);
675 }
676
677 /* Check conditional av table for additional permissions */
678 cond_compute_av(&policydb->te_cond_avtab, &avkey,
679 avd, xperms);
680
681 }
682 }
683
684 /*
685 * Remove any permissions prohibited by a constraint (this includes
686 * the MLS policy).
687 */
688 constraint = tclass_datum->constraints;
689 while (constraint) {
690 if ((constraint->permissions & (avd->allowed)) &&
691 !constraint_expr_eval(policydb, scontext, tcontext, NULL,
692 constraint->expr)) {
693 avd->allowed &= ~(constraint->permissions);
694 }
695 constraint = constraint->next;
696 }
697
698 /*
699 * If checking process transition permission and the
700 * role is changing, then check the (current_role, new_role)
701 * pair.
702 */
703 if (tclass == policydb->process_class &&
704 (avd->allowed & policydb->process_trans_perms) &&
705 scontext->role != tcontext->role) {
706 for (ra = policydb->role_allow; ra; ra = ra->next) {
707 if (scontext->role == ra->role &&
708 tcontext->role == ra->new_role)
709 break;
710 }
711 if (!ra)
712 avd->allowed &= ~policydb->process_trans_perms;
713 }
714
715 /*
716 * If the given source and target types have boundary
717 * constraint, lazy checks have to mask any violated
718 * permission and notice it to userspace via audit.
719 */
720 type_attribute_bounds_av(policydb, scontext, tcontext,
721 tclass, avd);
722}
723
724static int security_validtrans_handle_fail(struct selinux_policy *policy,
725 struct sidtab_entry *oentry,
726 struct sidtab_entry *nentry,
727 struct sidtab_entry *tentry,
728 u16 tclass)
729{
730 struct policydb *p = &policy->policydb;
731 struct sidtab *sidtab = policy->sidtab;
732 char *o = NULL, *n = NULL, *t = NULL;
733 u32 olen, nlen, tlen;
734
735 if (sidtab_entry_to_string(p, sidtab, oentry, &o, &olen))
736 goto out;
737 if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen))
738 goto out;
739 if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen))
740 goto out;
741 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
742 "op=security_validate_transition seresult=denied"
743 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
744 o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
745out:
746 kfree(o);
747 kfree(n);
748 kfree(t);
749
750 if (!enforcing_enabled())
751 return 0;
752 return -EPERM;
753}
754
755static int security_compute_validatetrans(u32 oldsid, u32 newsid, u32 tasksid,
756 u16 orig_tclass, bool user)
757{
758 struct selinux_policy *policy;
759 struct policydb *policydb;
760 struct sidtab *sidtab;
761 struct sidtab_entry *oentry;
762 struct sidtab_entry *nentry;
763 struct sidtab_entry *tentry;
764 struct class_datum *tclass_datum;
765 struct constraint_node *constraint;
766 u16 tclass;
767 int rc = 0;
768
769
770 if (!selinux_initialized())
771 return 0;
772
773 rcu_read_lock();
774
775 policy = rcu_dereference(selinux_state.policy);
776 policydb = &policy->policydb;
777 sidtab = policy->sidtab;
778
779 if (!user)
780 tclass = unmap_class(&policy->map, orig_tclass);
781 else
782 tclass = orig_tclass;
783
784 if (!tclass || tclass > policydb->p_classes.nprim) {
785 rc = -EINVAL;
786 goto out;
787 }
788 tclass_datum = policydb->class_val_to_struct[tclass - 1];
789
790 oentry = sidtab_search_entry(sidtab, oldsid);
791 if (!oentry) {
792 pr_err("SELinux: %s: unrecognized SID %d\n",
793 __func__, oldsid);
794 rc = -EINVAL;
795 goto out;
796 }
797
798 nentry = sidtab_search_entry(sidtab, newsid);
799 if (!nentry) {
800 pr_err("SELinux: %s: unrecognized SID %d\n",
801 __func__, newsid);
802 rc = -EINVAL;
803 goto out;
804 }
805
806 tentry = sidtab_search_entry(sidtab, tasksid);
807 if (!tentry) {
808 pr_err("SELinux: %s: unrecognized SID %d\n",
809 __func__, tasksid);
810 rc = -EINVAL;
811 goto out;
812 }
813
814 constraint = tclass_datum->validatetrans;
815 while (constraint) {
816 if (!constraint_expr_eval(policydb, &oentry->context,
817 &nentry->context, &tentry->context,
818 constraint->expr)) {
819 if (user)
820 rc = -EPERM;
821 else
822 rc = security_validtrans_handle_fail(policy,
823 oentry,
824 nentry,
825 tentry,
826 tclass);
827 goto out;
828 }
829 constraint = constraint->next;
830 }
831
832out:
833 rcu_read_unlock();
834 return rc;
835}
836
837int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid,
838 u16 tclass)
839{
840 return security_compute_validatetrans(oldsid, newsid, tasksid,
841 tclass, true);
842}
843
844int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
845 u16 orig_tclass)
846{
847 return security_compute_validatetrans(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(u32 old_sid, u32 new_sid)
861{
862 struct selinux_policy *policy;
863 struct policydb *policydb;
864 struct sidtab *sidtab;
865 struct sidtab_entry *old_entry, *new_entry;
866 struct type_datum *type;
867 u32 index;
868 int rc;
869
870 if (!selinux_initialized())
871 return 0;
872
873 rcu_read_lock();
874 policy = rcu_dereference(selinux_state.policy);
875 policydb = &policy->policydb;
876 sidtab = policy->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 rcu_read_unlock();
938
939 return rc;
940}
941
942static void avd_init(struct selinux_policy *policy, struct av_decision *avd)
943{
944 avd->allowed = 0;
945 avd->auditallow = 0;
946 avd->auditdeny = 0xffffffff;
947 if (policy)
948 avd->seqno = policy->latest_granting;
949 else
950 avd->seqno = 0;
951 avd->flags = 0;
952}
953
954static void update_xperms_extended_data(u8 specified,
955 struct extended_perms_data *from,
956 struct extended_perms_data *xp_data)
957{
958 unsigned int i;
959
960 switch (specified) {
961 case AVTAB_XPERMS_IOCTLDRIVER:
962 memset(xp_data->p, 0xff, sizeof(xp_data->p));
963 break;
964 case AVTAB_XPERMS_IOCTLFUNCTION:
965 case AVTAB_XPERMS_NLMSG:
966 for (i = 0; i < ARRAY_SIZE(xp_data->p); i++)
967 xp_data->p[i] |= from->p[i];
968 break;
969 }
970
971}
972
973void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
974 struct avtab_node *node)
975{
976 switch (node->datum.u.xperms->specified) {
977 case AVTAB_XPERMS_IOCTLFUNCTION:
978 if (xpermd->base_perm != AVC_EXT_IOCTL ||
979 xpermd->driver != node->datum.u.xperms->driver)
980 return;
981 break;
982 case AVTAB_XPERMS_IOCTLDRIVER:
983 if (xpermd->base_perm != AVC_EXT_IOCTL ||
984 !security_xperm_test(node->datum.u.xperms->perms.p,
985 xpermd->driver))
986 return;
987 break;
988 case AVTAB_XPERMS_NLMSG:
989 if (xpermd->base_perm != AVC_EXT_NLMSG ||
990 xpermd->driver != node->datum.u.xperms->driver)
991 return;
992 break;
993 default:
994 pr_warn_once(
995 "SELinux: unknown extended permission (%u) will be ignored\n",
996 node->datum.u.xperms->specified);
997 return;
998 }
999
1000 if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
1001 xpermd->used |= XPERMS_ALLOWED;
1002 update_xperms_extended_data(node->datum.u.xperms->specified,
1003 &node->datum.u.xperms->perms,
1004 xpermd->allowed);
1005 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
1006 xpermd->used |= XPERMS_AUDITALLOW;
1007 update_xperms_extended_data(node->datum.u.xperms->specified,
1008 &node->datum.u.xperms->perms,
1009 xpermd->auditallow);
1010 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
1011 xpermd->used |= XPERMS_DONTAUDIT;
1012 update_xperms_extended_data(node->datum.u.xperms->specified,
1013 &node->datum.u.xperms->perms,
1014 xpermd->dontaudit);
1015 } else {
1016 pr_warn_once("SELinux: unknown specified key (%u)\n",
1017 node->key.specified);
1018 }
1019}
1020
1021void security_compute_xperms_decision(u32 ssid,
1022 u32 tsid,
1023 u16 orig_tclass,
1024 u8 driver,
1025 u8 base_perm,
1026 struct extended_perms_decision *xpermd)
1027{
1028 struct selinux_policy *policy;
1029 struct policydb *policydb;
1030 struct sidtab *sidtab;
1031 u16 tclass;
1032 struct context *scontext, *tcontext;
1033 struct avtab_key avkey;
1034 struct avtab_node *node;
1035 struct ebitmap *sattr, *tattr;
1036 struct ebitmap_node *snode, *tnode;
1037 unsigned int i, j;
1038
1039 xpermd->base_perm = base_perm;
1040 xpermd->driver = driver;
1041 xpermd->used = 0;
1042 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1043 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1044 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1045
1046 rcu_read_lock();
1047 if (!selinux_initialized())
1048 goto allow;
1049
1050 policy = rcu_dereference(selinux_state.policy);
1051 policydb = &policy->policydb;
1052 sidtab = policy->sidtab;
1053
1054 scontext = sidtab_search(sidtab, ssid);
1055 if (!scontext) {
1056 pr_err("SELinux: %s: unrecognized SID %d\n",
1057 __func__, ssid);
1058 goto out;
1059 }
1060
1061 tcontext = sidtab_search(sidtab, tsid);
1062 if (!tcontext) {
1063 pr_err("SELinux: %s: unrecognized SID %d\n",
1064 __func__, tsid);
1065 goto out;
1066 }
1067
1068 tclass = unmap_class(&policy->map, orig_tclass);
1069 if (unlikely(orig_tclass && !tclass)) {
1070 if (policydb->allow_unknown)
1071 goto allow;
1072 goto out;
1073 }
1074
1075
1076 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1077 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1078 goto out;
1079 }
1080
1081 avkey.target_class = tclass;
1082 avkey.specified = AVTAB_XPERMS;
1083 sattr = &policydb->type_attr_map_array[scontext->type - 1];
1084 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
1085 ebitmap_for_each_positive_bit(sattr, snode, i) {
1086 ebitmap_for_each_positive_bit(tattr, tnode, j) {
1087 avkey.source_type = i + 1;
1088 avkey.target_type = j + 1;
1089 for (node = avtab_search_node(&policydb->te_avtab,
1090 &avkey);
1091 node;
1092 node = avtab_search_node_next(node, avkey.specified))
1093 services_compute_xperms_decision(xpermd, node);
1094
1095 cond_compute_xperms(&policydb->te_cond_avtab,
1096 &avkey, xpermd);
1097 }
1098 }
1099out:
1100 rcu_read_unlock();
1101 return;
1102allow:
1103 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1104 goto out;
1105}
1106
1107/**
1108 * security_compute_av - Compute access vector decisions.
1109 * @ssid: source security identifier
1110 * @tsid: target security identifier
1111 * @orig_tclass: target security class
1112 * @avd: access vector decisions
1113 * @xperms: extended permissions
1114 *
1115 * Compute a set of access vector decisions based on the
1116 * SID pair (@ssid, @tsid) for the permissions in @tclass.
1117 */
1118void security_compute_av(u32 ssid,
1119 u32 tsid,
1120 u16 orig_tclass,
1121 struct av_decision *avd,
1122 struct extended_perms *xperms)
1123{
1124 struct selinux_policy *policy;
1125 struct policydb *policydb;
1126 struct sidtab *sidtab;
1127 u16 tclass;
1128 struct context *scontext = NULL, *tcontext = NULL;
1129
1130 rcu_read_lock();
1131 policy = rcu_dereference(selinux_state.policy);
1132 avd_init(policy, avd);
1133 xperms->len = 0;
1134 if (!selinux_initialized())
1135 goto allow;
1136
1137 policydb = &policy->policydb;
1138 sidtab = policy->sidtab;
1139
1140 scontext = sidtab_search(sidtab, ssid);
1141 if (!scontext) {
1142 pr_err("SELinux: %s: unrecognized SID %d\n",
1143 __func__, ssid);
1144 goto out;
1145 }
1146
1147 /* permissive domain? */
1148 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1149 avd->flags |= AVD_FLAGS_PERMISSIVE;
1150
1151 tcontext = sidtab_search(sidtab, tsid);
1152 if (!tcontext) {
1153 pr_err("SELinux: %s: unrecognized SID %d\n",
1154 __func__, tsid);
1155 goto out;
1156 }
1157
1158 tclass = unmap_class(&policy->map, orig_tclass);
1159 if (unlikely(orig_tclass && !tclass)) {
1160 if (policydb->allow_unknown)
1161 goto allow;
1162 goto out;
1163 }
1164 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1165 xperms);
1166 map_decision(&policy->map, orig_tclass, avd,
1167 policydb->allow_unknown);
1168out:
1169 rcu_read_unlock();
1170 return;
1171allow:
1172 avd->allowed = 0xffffffff;
1173 goto out;
1174}
1175
1176void security_compute_av_user(u32 ssid,
1177 u32 tsid,
1178 u16 tclass,
1179 struct av_decision *avd)
1180{
1181 struct selinux_policy *policy;
1182 struct policydb *policydb;
1183 struct sidtab *sidtab;
1184 struct context *scontext = NULL, *tcontext = NULL;
1185
1186 rcu_read_lock();
1187 policy = rcu_dereference(selinux_state.policy);
1188 avd_init(policy, avd);
1189 if (!selinux_initialized())
1190 goto allow;
1191
1192 policydb = &policy->policydb;
1193 sidtab = policy->sidtab;
1194
1195 scontext = sidtab_search(sidtab, ssid);
1196 if (!scontext) {
1197 pr_err("SELinux: %s: unrecognized SID %d\n",
1198 __func__, ssid);
1199 goto out;
1200 }
1201
1202 /* permissive domain? */
1203 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1204 avd->flags |= AVD_FLAGS_PERMISSIVE;
1205
1206 tcontext = sidtab_search(sidtab, tsid);
1207 if (!tcontext) {
1208 pr_err("SELinux: %s: unrecognized SID %d\n",
1209 __func__, tsid);
1210 goto out;
1211 }
1212
1213 if (unlikely(!tclass)) {
1214 if (policydb->allow_unknown)
1215 goto allow;
1216 goto out;
1217 }
1218
1219 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1220 NULL);
1221 out:
1222 rcu_read_unlock();
1223 return;
1224allow:
1225 avd->allowed = 0xffffffff;
1226 goto out;
1227}
1228
1229/*
1230 * Write the security context string representation of
1231 * the context structure `context' into a dynamically
1232 * allocated string of the correct size. Set `*scontext'
1233 * to point to this string and set `*scontext_len' to
1234 * the length of the string.
1235 */
1236static int context_struct_to_string(struct policydb *p,
1237 struct context *context,
1238 char **scontext, u32 *scontext_len)
1239{
1240 char *scontextp;
1241
1242 if (scontext)
1243 *scontext = NULL;
1244 *scontext_len = 0;
1245
1246 if (context->len) {
1247 *scontext_len = context->len;
1248 if (scontext) {
1249 *scontext = kstrdup(context->str, GFP_ATOMIC);
1250 if (!(*scontext))
1251 return -ENOMEM;
1252 }
1253 return 0;
1254 }
1255
1256 /* Compute the size of the context. */
1257 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1258 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1259 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1260 *scontext_len += mls_compute_context_len(p, context);
1261
1262 if (!scontext)
1263 return 0;
1264
1265 /* Allocate space for the context; caller must free this space. */
1266 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1267 if (!scontextp)
1268 return -ENOMEM;
1269 *scontext = scontextp;
1270
1271 /*
1272 * Copy the user name, role name and type name into the context.
1273 */
1274 scontextp += sprintf(scontextp, "%s:%s:%s",
1275 sym_name(p, SYM_USERS, context->user - 1),
1276 sym_name(p, SYM_ROLES, context->role - 1),
1277 sym_name(p, SYM_TYPES, context->type - 1));
1278
1279 mls_sid_to_context(p, context, &scontextp);
1280
1281 *scontextp = 0;
1282
1283 return 0;
1284}
1285
1286static int sidtab_entry_to_string(struct policydb *p,
1287 struct sidtab *sidtab,
1288 struct sidtab_entry *entry,
1289 char **scontext, u32 *scontext_len)
1290{
1291 int rc = sidtab_sid2str_get(sidtab, entry, scontext, scontext_len);
1292
1293 if (rc != -ENOENT)
1294 return rc;
1295
1296 rc = context_struct_to_string(p, &entry->context, scontext,
1297 scontext_len);
1298 if (!rc && scontext)
1299 sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len);
1300 return rc;
1301}
1302
1303#include "initial_sid_to_string.h"
1304
1305int security_sidtab_hash_stats(char *page)
1306{
1307 struct selinux_policy *policy;
1308 int rc;
1309
1310 if (!selinux_initialized()) {
1311 pr_err("SELinux: %s: called before initial load_policy\n",
1312 __func__);
1313 return -EINVAL;
1314 }
1315
1316 rcu_read_lock();
1317 policy = rcu_dereference(selinux_state.policy);
1318 rc = sidtab_hash_stats(policy->sidtab, page);
1319 rcu_read_unlock();
1320
1321 return rc;
1322}
1323
1324const char *security_get_initial_sid_context(u32 sid)
1325{
1326 if (unlikely(sid > SECINITSID_NUM))
1327 return NULL;
1328 return initial_sid_to_string[sid];
1329}
1330
1331static int security_sid_to_context_core(u32 sid, char **scontext,
1332 u32 *scontext_len, int force,
1333 int only_invalid)
1334{
1335 struct selinux_policy *policy;
1336 struct policydb *policydb;
1337 struct sidtab *sidtab;
1338 struct sidtab_entry *entry;
1339 int rc = 0;
1340
1341 if (scontext)
1342 *scontext = NULL;
1343 *scontext_len = 0;
1344
1345 if (!selinux_initialized()) {
1346 if (sid <= SECINITSID_NUM) {
1347 char *scontextp;
1348 const char *s;
1349
1350 /*
1351 * Before the policy is loaded, translate
1352 * SECINITSID_INIT to "kernel", because systemd and
1353 * libselinux < 2.6 take a getcon_raw() result that is
1354 * both non-null and not "kernel" to mean that a policy
1355 * is already loaded.
1356 */
1357 if (sid == SECINITSID_INIT)
1358 sid = SECINITSID_KERNEL;
1359
1360 s = initial_sid_to_string[sid];
1361 if (!s)
1362 return -EINVAL;
1363 *scontext_len = strlen(s) + 1;
1364 if (!scontext)
1365 return 0;
1366 scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC);
1367 if (!scontextp)
1368 return -ENOMEM;
1369 *scontext = scontextp;
1370 return 0;
1371 }
1372 pr_err("SELinux: %s: called before initial "
1373 "load_policy on unknown SID %d\n", __func__, sid);
1374 return -EINVAL;
1375 }
1376 rcu_read_lock();
1377 policy = rcu_dereference(selinux_state.policy);
1378 policydb = &policy->policydb;
1379 sidtab = policy->sidtab;
1380
1381 if (force)
1382 entry = sidtab_search_entry_force(sidtab, sid);
1383 else
1384 entry = sidtab_search_entry(sidtab, sid);
1385 if (!entry) {
1386 pr_err("SELinux: %s: unrecognized SID %d\n",
1387 __func__, sid);
1388 rc = -EINVAL;
1389 goto out_unlock;
1390 }
1391 if (only_invalid && !entry->context.len)
1392 goto out_unlock;
1393
1394 rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext,
1395 scontext_len);
1396
1397out_unlock:
1398 rcu_read_unlock();
1399 return rc;
1400
1401}
1402
1403/**
1404 * security_sid_to_context - Obtain a context for a given SID.
1405 * @sid: security identifier, SID
1406 * @scontext: security context
1407 * @scontext_len: length in bytes
1408 *
1409 * Write the string representation of the context associated with @sid
1410 * into a dynamically allocated string of the correct size. Set @scontext
1411 * to point to this string and set @scontext_len to the length of the string.
1412 */
1413int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1414{
1415 return security_sid_to_context_core(sid, scontext,
1416 scontext_len, 0, 0);
1417}
1418
1419int security_sid_to_context_force(u32 sid,
1420 char **scontext, u32 *scontext_len)
1421{
1422 return security_sid_to_context_core(sid, scontext,
1423 scontext_len, 1, 0);
1424}
1425
1426/**
1427 * security_sid_to_context_inval - Obtain a context for a given SID if it
1428 * is invalid.
1429 * @sid: security identifier, SID
1430 * @scontext: security context
1431 * @scontext_len: length in bytes
1432 *
1433 * Write the string representation of the context associated with @sid
1434 * into a dynamically allocated string of the correct size, but only if the
1435 * context is invalid in the current policy. Set @scontext to point to
1436 * this string (or NULL if the context is valid) and set @scontext_len to
1437 * the length of the string (or 0 if the context is valid).
1438 */
1439int security_sid_to_context_inval(u32 sid,
1440 char **scontext, u32 *scontext_len)
1441{
1442 return security_sid_to_context_core(sid, scontext,
1443 scontext_len, 1, 1);
1444}
1445
1446/*
1447 * Caveat: Mutates scontext.
1448 */
1449static int string_to_context_struct(struct policydb *pol,
1450 struct sidtab *sidtabp,
1451 char *scontext,
1452 struct context *ctx,
1453 u32 def_sid)
1454{
1455 struct role_datum *role;
1456 struct type_datum *typdatum;
1457 struct user_datum *usrdatum;
1458 char *scontextp, *p, oldc;
1459 int rc = 0;
1460
1461 context_init(ctx);
1462
1463 /* Parse the security context. */
1464
1465 rc = -EINVAL;
1466 scontextp = scontext;
1467
1468 /* Extract the user. */
1469 p = scontextp;
1470 while (*p && *p != ':')
1471 p++;
1472
1473 if (*p == 0)
1474 goto out;
1475
1476 *p++ = 0;
1477
1478 usrdatum = symtab_search(&pol->p_users, scontextp);
1479 if (!usrdatum)
1480 goto out;
1481
1482 ctx->user = usrdatum->value;
1483
1484 /* Extract role. */
1485 scontextp = p;
1486 while (*p && *p != ':')
1487 p++;
1488
1489 if (*p == 0)
1490 goto out;
1491
1492 *p++ = 0;
1493
1494 role = symtab_search(&pol->p_roles, scontextp);
1495 if (!role)
1496 goto out;
1497 ctx->role = role->value;
1498
1499 /* Extract type. */
1500 scontextp = p;
1501 while (*p && *p != ':')
1502 p++;
1503 oldc = *p;
1504 *p++ = 0;
1505
1506 typdatum = symtab_search(&pol->p_types, scontextp);
1507 if (!typdatum || typdatum->attribute)
1508 goto out;
1509
1510 ctx->type = typdatum->value;
1511
1512 rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid);
1513 if (rc)
1514 goto out;
1515
1516 /* Check the validity of the new context. */
1517 rc = -EINVAL;
1518 if (!policydb_context_isvalid(pol, ctx))
1519 goto out;
1520 rc = 0;
1521out:
1522 if (rc)
1523 context_destroy(ctx);
1524 return rc;
1525}
1526
1527static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1528 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1529 int force)
1530{
1531 struct selinux_policy *policy;
1532 struct policydb *policydb;
1533 struct sidtab *sidtab;
1534 char *scontext2, *str = NULL;
1535 struct context context;
1536 int rc = 0;
1537
1538 /* An empty security context is never valid. */
1539 if (!scontext_len)
1540 return -EINVAL;
1541
1542 /* Copy the string to allow changes and ensure a NUL terminator */
1543 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags);
1544 if (!scontext2)
1545 return -ENOMEM;
1546
1547 if (!selinux_initialized()) {
1548 u32 i;
1549
1550 for (i = 1; i < SECINITSID_NUM; i++) {
1551 const char *s = initial_sid_to_string[i];
1552
1553 if (s && !strcmp(s, scontext2)) {
1554 *sid = i;
1555 goto out;
1556 }
1557 }
1558 *sid = SECINITSID_KERNEL;
1559 goto out;
1560 }
1561 *sid = SECSID_NULL;
1562
1563 if (force) {
1564 /* Save another copy for storing in uninterpreted form */
1565 rc = -ENOMEM;
1566 str = kstrdup(scontext2, gfp_flags);
1567 if (!str)
1568 goto out;
1569 }
1570retry:
1571 rcu_read_lock();
1572 policy = rcu_dereference(selinux_state.policy);
1573 policydb = &policy->policydb;
1574 sidtab = policy->sidtab;
1575 rc = string_to_context_struct(policydb, sidtab, scontext2,
1576 &context, def_sid);
1577 if (rc == -EINVAL && force) {
1578 context.str = str;
1579 context.len = strlen(str) + 1;
1580 str = NULL;
1581 } else if (rc)
1582 goto out_unlock;
1583 rc = sidtab_context_to_sid(sidtab, &context, sid);
1584 if (rc == -ESTALE) {
1585 rcu_read_unlock();
1586 if (context.str) {
1587 str = context.str;
1588 context.str = NULL;
1589 }
1590 context_destroy(&context);
1591 goto retry;
1592 }
1593 context_destroy(&context);
1594out_unlock:
1595 rcu_read_unlock();
1596out:
1597 kfree(scontext2);
1598 kfree(str);
1599 return rc;
1600}
1601
1602/**
1603 * security_context_to_sid - Obtain a SID for a given security context.
1604 * @scontext: security context
1605 * @scontext_len: length in bytes
1606 * @sid: security identifier, SID
1607 * @gfp: context for the allocation
1608 *
1609 * Obtains a SID associated with the security context that
1610 * has the string representation specified by @scontext.
1611 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1612 * memory is available, or 0 on success.
1613 */
1614int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid,
1615 gfp_t gfp)
1616{
1617 return security_context_to_sid_core(scontext, scontext_len,
1618 sid, SECSID_NULL, gfp, 0);
1619}
1620
1621int security_context_str_to_sid(const char *scontext, u32 *sid, gfp_t gfp)
1622{
1623 return security_context_to_sid(scontext, strlen(scontext),
1624 sid, gfp);
1625}
1626
1627/**
1628 * security_context_to_sid_default - Obtain a SID for a given security context,
1629 * falling back to specified default if needed.
1630 *
1631 * @scontext: security context
1632 * @scontext_len: length in bytes
1633 * @sid: security identifier, SID
1634 * @def_sid: default SID to assign on error
1635 * @gfp_flags: the allocator get-free-page (GFP) flags
1636 *
1637 * Obtains a SID associated with the security context that
1638 * has the string representation specified by @scontext.
1639 * The default SID is passed to the MLS layer to be used to allow
1640 * kernel labeling of the MLS field if the MLS field is not present
1641 * (for upgrading to MLS without full relabel).
1642 * Implicitly forces adding of the context even if it cannot be mapped yet.
1643 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1644 * memory is available, or 0 on success.
1645 */
1646int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1647 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1648{
1649 return security_context_to_sid_core(scontext, scontext_len,
1650 sid, def_sid, gfp_flags, 1);
1651}
1652
1653int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1654 u32 *sid)
1655{
1656 return security_context_to_sid_core(scontext, scontext_len,
1657 sid, SECSID_NULL, GFP_KERNEL, 1);
1658}
1659
1660static int compute_sid_handle_invalid_context(
1661 struct selinux_policy *policy,
1662 struct sidtab_entry *sentry,
1663 struct sidtab_entry *tentry,
1664 u16 tclass,
1665 struct context *newcontext)
1666{
1667 struct policydb *policydb = &policy->policydb;
1668 struct sidtab *sidtab = policy->sidtab;
1669 char *s = NULL, *t = NULL, *n = NULL;
1670 u32 slen, tlen, nlen;
1671 struct audit_buffer *ab;
1672
1673 if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen))
1674 goto out;
1675 if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen))
1676 goto out;
1677 if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1678 goto out;
1679 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR);
1680 if (!ab)
1681 goto out;
1682 audit_log_format(ab,
1683 "op=security_compute_sid invalid_context=");
1684 /* no need to record the NUL with untrusted strings */
1685 audit_log_n_untrustedstring(ab, n, nlen - 1);
1686 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s",
1687 s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1688 audit_log_end(ab);
1689out:
1690 kfree(s);
1691 kfree(t);
1692 kfree(n);
1693 if (!enforcing_enabled())
1694 return 0;
1695 return -EACCES;
1696}
1697
1698static void filename_compute_type(struct policydb *policydb,
1699 struct context *newcontext,
1700 u32 stype, u32 ttype, u16 tclass,
1701 const char *objname)
1702{
1703 struct filename_trans_key ft;
1704 struct filename_trans_datum *datum;
1705
1706 /*
1707 * Most filename trans rules are going to live in specific directories
1708 * like /dev or /var/run. This bitmap will quickly skip rule searches
1709 * if the ttype does not contain any rules.
1710 */
1711 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1712 return;
1713
1714 ft.ttype = ttype;
1715 ft.tclass = tclass;
1716 ft.name = objname;
1717
1718 datum = policydb_filenametr_search(policydb, &ft);
1719 while (datum) {
1720 if (ebitmap_get_bit(&datum->stypes, stype - 1)) {
1721 newcontext->type = datum->otype;
1722 return;
1723 }
1724 datum = datum->next;
1725 }
1726}
1727
1728static int security_compute_sid(u32 ssid,
1729 u32 tsid,
1730 u16 orig_tclass,
1731 u16 specified,
1732 const char *objname,
1733 u32 *out_sid,
1734 bool kern)
1735{
1736 struct selinux_policy *policy;
1737 struct policydb *policydb;
1738 struct sidtab *sidtab;
1739 struct class_datum *cladatum;
1740 struct context *scontext, *tcontext, newcontext;
1741 struct sidtab_entry *sentry, *tentry;
1742 struct avtab_key avkey;
1743 struct avtab_node *avnode, *node;
1744 u16 tclass;
1745 int rc = 0;
1746 bool sock;
1747
1748 if (!selinux_initialized()) {
1749 switch (orig_tclass) {
1750 case SECCLASS_PROCESS: /* kernel value */
1751 *out_sid = ssid;
1752 break;
1753 default:
1754 *out_sid = tsid;
1755 break;
1756 }
1757 goto out;
1758 }
1759
1760retry:
1761 cladatum = NULL;
1762 context_init(&newcontext);
1763
1764 rcu_read_lock();
1765
1766 policy = rcu_dereference(selinux_state.policy);
1767
1768 if (kern) {
1769 tclass = unmap_class(&policy->map, orig_tclass);
1770 sock = security_is_socket_class(orig_tclass);
1771 } else {
1772 tclass = orig_tclass;
1773 sock = security_is_socket_class(map_class(&policy->map,
1774 tclass));
1775 }
1776
1777 policydb = &policy->policydb;
1778 sidtab = policy->sidtab;
1779
1780 sentry = sidtab_search_entry(sidtab, ssid);
1781 if (!sentry) {
1782 pr_err("SELinux: %s: unrecognized SID %d\n",
1783 __func__, ssid);
1784 rc = -EINVAL;
1785 goto out_unlock;
1786 }
1787 tentry = sidtab_search_entry(sidtab, tsid);
1788 if (!tentry) {
1789 pr_err("SELinux: %s: unrecognized SID %d\n",
1790 __func__, tsid);
1791 rc = -EINVAL;
1792 goto out_unlock;
1793 }
1794
1795 scontext = &sentry->context;
1796 tcontext = &tentry->context;
1797
1798 if (tclass && tclass <= policydb->p_classes.nprim)
1799 cladatum = policydb->class_val_to_struct[tclass - 1];
1800
1801 /* Set the user identity. */
1802 switch (specified) {
1803 case AVTAB_TRANSITION:
1804 case AVTAB_CHANGE:
1805 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1806 newcontext.user = tcontext->user;
1807 } else {
1808 /* notice this gets both DEFAULT_SOURCE and unset */
1809 /* Use the process user identity. */
1810 newcontext.user = scontext->user;
1811 }
1812 break;
1813 case AVTAB_MEMBER:
1814 /* Use the related object owner. */
1815 newcontext.user = tcontext->user;
1816 break;
1817 }
1818
1819 /* Set the role to default values. */
1820 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1821 newcontext.role = scontext->role;
1822 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1823 newcontext.role = tcontext->role;
1824 } else {
1825 if ((tclass == policydb->process_class) || sock)
1826 newcontext.role = scontext->role;
1827 else
1828 newcontext.role = OBJECT_R_VAL;
1829 }
1830
1831 /* Set the type.
1832 * Look for a type transition/member/change rule.
1833 */
1834 avkey.source_type = scontext->type;
1835 avkey.target_type = tcontext->type;
1836 avkey.target_class = tclass;
1837 avkey.specified = specified;
1838 avnode = avtab_search_node(&policydb->te_avtab, &avkey);
1839
1840 /* If no permanent rule, also check for enabled conditional rules */
1841 if (!avnode) {
1842 node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1843 for (; node; node = avtab_search_node_next(node, specified)) {
1844 if (node->key.specified & AVTAB_ENABLED) {
1845 avnode = node;
1846 break;
1847 }
1848 }
1849 }
1850
1851 /* If a permanent rule is found, use the type from
1852 * the type transition/member/change rule. Otherwise,
1853 * set the type to its default values.
1854 */
1855 if (avnode) {
1856 newcontext.type = avnode->datum.u.data;
1857 } else if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1858 newcontext.type = scontext->type;
1859 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1860 newcontext.type = tcontext->type;
1861 } else {
1862 if ((tclass == policydb->process_class) || sock) {
1863 /* Use the type of process. */
1864 newcontext.type = scontext->type;
1865 } else {
1866 /* Use the type of the related object. */
1867 newcontext.type = tcontext->type;
1868 }
1869 }
1870
1871 /* if we have a objname this is a file trans check so check those rules */
1872 if (objname)
1873 filename_compute_type(policydb, &newcontext, scontext->type,
1874 tcontext->type, tclass, objname);
1875
1876 /* Check for class-specific changes. */
1877 if (specified & AVTAB_TRANSITION) {
1878 /* Look for a role transition rule. */
1879 struct role_trans_datum *rtd;
1880 struct role_trans_key rtk = {
1881 .role = scontext->role,
1882 .type = tcontext->type,
1883 .tclass = tclass,
1884 };
1885
1886 rtd = policydb_roletr_search(policydb, &rtk);
1887 if (rtd)
1888 newcontext.role = rtd->new_role;
1889 }
1890
1891 /* Set the MLS attributes.
1892 This is done last because it may allocate memory. */
1893 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1894 &newcontext, sock);
1895 if (rc)
1896 goto out_unlock;
1897
1898 /* Check the validity of the context. */
1899 if (!policydb_context_isvalid(policydb, &newcontext)) {
1900 rc = compute_sid_handle_invalid_context(policy, sentry,
1901 tentry, tclass,
1902 &newcontext);
1903 if (rc)
1904 goto out_unlock;
1905 }
1906 /* Obtain the sid for the context. */
1907 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1908 if (rc == -ESTALE) {
1909 rcu_read_unlock();
1910 context_destroy(&newcontext);
1911 goto retry;
1912 }
1913out_unlock:
1914 rcu_read_unlock();
1915 context_destroy(&newcontext);
1916out:
1917 return rc;
1918}
1919
1920/**
1921 * security_transition_sid - Compute the SID for a new subject/object.
1922 * @ssid: source security identifier
1923 * @tsid: target security identifier
1924 * @tclass: target security class
1925 * @qstr: object name
1926 * @out_sid: security identifier for new subject/object
1927 *
1928 * Compute a SID to use for labeling a new subject or object in the
1929 * class @tclass based on a SID pair (@ssid, @tsid).
1930 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1931 * if insufficient memory is available, or %0 if the new SID was
1932 * computed successfully.
1933 */
1934int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1935 const struct qstr *qstr, u32 *out_sid)
1936{
1937 return security_compute_sid(ssid, tsid, tclass,
1938 AVTAB_TRANSITION,
1939 qstr ? qstr->name : NULL, out_sid, true);
1940}
1941
1942int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1943 const char *objname, u32 *out_sid)
1944{
1945 return security_compute_sid(ssid, tsid, tclass,
1946 AVTAB_TRANSITION,
1947 objname, out_sid, false);
1948}
1949
1950/**
1951 * security_member_sid - Compute the SID for member selection.
1952 * @ssid: source security identifier
1953 * @tsid: target security identifier
1954 * @tclass: target security class
1955 * @out_sid: security identifier for selected member
1956 *
1957 * Compute a SID to use when selecting a member of a polyinstantiated
1958 * object of class @tclass based on a SID pair (@ssid, @tsid).
1959 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1960 * if insufficient memory is available, or %0 if the SID was
1961 * computed successfully.
1962 */
1963int security_member_sid(u32 ssid,
1964 u32 tsid,
1965 u16 tclass,
1966 u32 *out_sid)
1967{
1968 return security_compute_sid(ssid, tsid, tclass,
1969 AVTAB_MEMBER, NULL,
1970 out_sid, false);
1971}
1972
1973/**
1974 * security_change_sid - Compute the SID for object relabeling.
1975 * @ssid: source security identifier
1976 * @tsid: target security identifier
1977 * @tclass: target security class
1978 * @out_sid: security identifier for selected member
1979 *
1980 * Compute a SID to use for relabeling an object of class @tclass
1981 * based on a SID pair (@ssid, @tsid).
1982 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1983 * if insufficient memory is available, or %0 if the SID was
1984 * computed successfully.
1985 */
1986int security_change_sid(u32 ssid,
1987 u32 tsid,
1988 u16 tclass,
1989 u32 *out_sid)
1990{
1991 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1992 out_sid, false);
1993}
1994
1995static inline int convert_context_handle_invalid_context(
1996 struct policydb *policydb,
1997 struct context *context)
1998{
1999 char *s;
2000 u32 len;
2001
2002 if (enforcing_enabled())
2003 return -EINVAL;
2004
2005 if (!context_struct_to_string(policydb, context, &s, &len)) {
2006 pr_warn("SELinux: Context %s would be invalid if enforcing\n",
2007 s);
2008 kfree(s);
2009 }
2010 return 0;
2011}
2012
2013/**
2014 * services_convert_context - Convert a security context across policies.
2015 * @args: populated convert_context_args struct
2016 * @oldc: original context
2017 * @newc: converted context
2018 * @gfp_flags: allocation flags
2019 *
2020 * Convert the values in the security context structure @oldc from the values
2021 * specified in the policy @args->oldp to the values specified in the policy
2022 * @args->newp, storing the new context in @newc, and verifying that the
2023 * context is valid under the new policy.
2024 */
2025int services_convert_context(struct convert_context_args *args,
2026 struct context *oldc, struct context *newc,
2027 gfp_t gfp_flags)
2028{
2029 struct ocontext *oc;
2030 struct role_datum *role;
2031 struct type_datum *typdatum;
2032 struct user_datum *usrdatum;
2033 char *s;
2034 u32 len;
2035 int rc;
2036
2037 if (oldc->str) {
2038 s = kstrdup(oldc->str, gfp_flags);
2039 if (!s)
2040 return -ENOMEM;
2041
2042 rc = string_to_context_struct(args->newp, NULL, s, newc, SECSID_NULL);
2043 if (rc == -EINVAL) {
2044 /*
2045 * Retain string representation for later mapping.
2046 *
2047 * IMPORTANT: We need to copy the contents of oldc->str
2048 * back into s again because string_to_context_struct()
2049 * may have garbled it.
2050 */
2051 memcpy(s, oldc->str, oldc->len);
2052 context_init(newc);
2053 newc->str = s;
2054 newc->len = oldc->len;
2055 return 0;
2056 }
2057 kfree(s);
2058 if (rc) {
2059 /* Other error condition, e.g. ENOMEM. */
2060 pr_err("SELinux: Unable to map context %s, rc = %d.\n",
2061 oldc->str, -rc);
2062 return rc;
2063 }
2064 pr_info("SELinux: Context %s became valid (mapped).\n",
2065 oldc->str);
2066 return 0;
2067 }
2068
2069 context_init(newc);
2070
2071 /* Convert the user. */
2072 usrdatum = symtab_search(&args->newp->p_users,
2073 sym_name(args->oldp, SYM_USERS, oldc->user - 1));
2074 if (!usrdatum)
2075 goto bad;
2076 newc->user = usrdatum->value;
2077
2078 /* Convert the role. */
2079 role = symtab_search(&args->newp->p_roles,
2080 sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
2081 if (!role)
2082 goto bad;
2083 newc->role = role->value;
2084
2085 /* Convert the type. */
2086 typdatum = symtab_search(&args->newp->p_types,
2087 sym_name(args->oldp, SYM_TYPES, oldc->type - 1));
2088 if (!typdatum)
2089 goto bad;
2090 newc->type = typdatum->value;
2091
2092 /* Convert the MLS fields if dealing with MLS policies */
2093 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2094 rc = mls_convert_context(args->oldp, args->newp, oldc, newc);
2095 if (rc)
2096 goto bad;
2097 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2098 /*
2099 * Switching between non-MLS and MLS policy:
2100 * ensure that the MLS fields of the context for all
2101 * existing entries in the sidtab are filled in with a
2102 * suitable default value, likely taken from one of the
2103 * initial SIDs.
2104 */
2105 oc = args->newp->ocontexts[OCON_ISID];
2106 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2107 oc = oc->next;
2108 if (!oc) {
2109 pr_err("SELinux: unable to look up"
2110 " the initial SIDs list\n");
2111 goto bad;
2112 }
2113 rc = mls_range_set(newc, &oc->context[0].range);
2114 if (rc)
2115 goto bad;
2116 }
2117
2118 /* Check the validity of the new context. */
2119 if (!policydb_context_isvalid(args->newp, newc)) {
2120 rc = convert_context_handle_invalid_context(args->oldp, oldc);
2121 if (rc)
2122 goto bad;
2123 }
2124
2125 return 0;
2126bad:
2127 /* Map old representation to string and save it. */
2128 rc = context_struct_to_string(args->oldp, oldc, &s, &len);
2129 if (rc)
2130 return rc;
2131 context_destroy(newc);
2132 newc->str = s;
2133 newc->len = len;
2134 pr_info("SELinux: Context %s became invalid (unmapped).\n",
2135 newc->str);
2136 return 0;
2137}
2138
2139static void security_load_policycaps(struct selinux_policy *policy)
2140{
2141 struct policydb *p;
2142 unsigned int i;
2143 struct ebitmap_node *node;
2144
2145 p = &policy->policydb;
2146
2147 for (i = 0; i < ARRAY_SIZE(selinux_state.policycap); i++)
2148 WRITE_ONCE(selinux_state.policycap[i],
2149 ebitmap_get_bit(&p->policycaps, i));
2150
2151 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2152 pr_info("SELinux: policy capability %s=%d\n",
2153 selinux_policycap_names[i],
2154 ebitmap_get_bit(&p->policycaps, i));
2155
2156 ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2157 if (i >= ARRAY_SIZE(selinux_policycap_names))
2158 pr_info("SELinux: unknown policy capability %u\n",
2159 i);
2160 }
2161}
2162
2163static int security_preserve_bools(struct selinux_policy *oldpolicy,
2164 struct selinux_policy *newpolicy);
2165
2166static void selinux_policy_free(struct selinux_policy *policy)
2167{
2168 if (!policy)
2169 return;
2170
2171 sidtab_destroy(policy->sidtab);
2172 kfree(policy->map.mapping);
2173 policydb_destroy(&policy->policydb);
2174 kfree(policy->sidtab);
2175 kfree(policy);
2176}
2177
2178static void selinux_policy_cond_free(struct selinux_policy *policy)
2179{
2180 cond_policydb_destroy_dup(&policy->policydb);
2181 kfree(policy);
2182}
2183
2184void selinux_policy_cancel(struct selinux_load_state *load_state)
2185{
2186 struct selinux_state *state = &selinux_state;
2187 struct selinux_policy *oldpolicy;
2188
2189 oldpolicy = rcu_dereference_protected(state->policy,
2190 lockdep_is_held(&state->policy_mutex));
2191
2192 sidtab_cancel_convert(oldpolicy->sidtab);
2193 selinux_policy_free(load_state->policy);
2194 kfree(load_state->convert_data);
2195}
2196
2197static void selinux_notify_policy_change(u32 seqno)
2198{
2199 /* Flush external caches and notify userspace of policy load */
2200 avc_ss_reset(seqno);
2201 selnl_notify_policyload(seqno);
2202 selinux_status_update_policyload(seqno);
2203 selinux_netlbl_cache_invalidate();
2204 selinux_xfrm_notify_policyload();
2205 selinux_ima_measure_state_locked();
2206}
2207
2208void selinux_policy_commit(struct selinux_load_state *load_state)
2209{
2210 struct selinux_state *state = &selinux_state;
2211 struct selinux_policy *oldpolicy, *newpolicy = load_state->policy;
2212 unsigned long flags;
2213 u32 seqno;
2214
2215 oldpolicy = rcu_dereference_protected(state->policy,
2216 lockdep_is_held(&state->policy_mutex));
2217
2218 /* If switching between different policy types, log MLS status */
2219 if (oldpolicy) {
2220 if (oldpolicy->policydb.mls_enabled && !newpolicy->policydb.mls_enabled)
2221 pr_info("SELinux: Disabling MLS support...\n");
2222 else if (!oldpolicy->policydb.mls_enabled && newpolicy->policydb.mls_enabled)
2223 pr_info("SELinux: Enabling MLS support...\n");
2224 }
2225
2226 /* Set latest granting seqno for new policy. */
2227 if (oldpolicy)
2228 newpolicy->latest_granting = oldpolicy->latest_granting + 1;
2229 else
2230 newpolicy->latest_granting = 1;
2231 seqno = newpolicy->latest_granting;
2232
2233 /* Install the new policy. */
2234 if (oldpolicy) {
2235 sidtab_freeze_begin(oldpolicy->sidtab, &flags);
2236 rcu_assign_pointer(state->policy, newpolicy);
2237 sidtab_freeze_end(oldpolicy->sidtab, &flags);
2238 } else {
2239 rcu_assign_pointer(state->policy, newpolicy);
2240 }
2241
2242 /* Load the policycaps from the new policy */
2243 security_load_policycaps(newpolicy);
2244
2245 if (!selinux_initialized()) {
2246 /*
2247 * After first policy load, the security server is
2248 * marked as initialized and ready to handle requests and
2249 * any objects created prior to policy load are then labeled.
2250 */
2251 selinux_mark_initialized();
2252 selinux_complete_init();
2253 }
2254
2255 /* Free the old policy */
2256 synchronize_rcu();
2257 selinux_policy_free(oldpolicy);
2258 kfree(load_state->convert_data);
2259
2260 /* Notify others of the policy change */
2261 selinux_notify_policy_change(seqno);
2262}
2263
2264/**
2265 * security_load_policy - Load a security policy configuration.
2266 * @data: binary policy data
2267 * @len: length of data in bytes
2268 * @load_state: policy load state
2269 *
2270 * Load a new set of security policy configuration data,
2271 * validate it and convert the SID table as necessary.
2272 * This function will flush the access vector cache after
2273 * loading the new policy.
2274 */
2275int security_load_policy(void *data, size_t len,
2276 struct selinux_load_state *load_state)
2277{
2278 struct selinux_state *state = &selinux_state;
2279 struct selinux_policy *newpolicy, *oldpolicy;
2280 struct selinux_policy_convert_data *convert_data;
2281 int rc = 0;
2282 struct policy_file file = { data, len }, *fp = &file;
2283
2284 newpolicy = kzalloc(sizeof(*newpolicy), GFP_KERNEL);
2285 if (!newpolicy)
2286 return -ENOMEM;
2287
2288 newpolicy->sidtab = kzalloc(sizeof(*newpolicy->sidtab), GFP_KERNEL);
2289 if (!newpolicy->sidtab) {
2290 rc = -ENOMEM;
2291 goto err_policy;
2292 }
2293
2294 rc = policydb_read(&newpolicy->policydb, fp);
2295 if (rc)
2296 goto err_sidtab;
2297
2298 newpolicy->policydb.len = len;
2299 rc = selinux_set_mapping(&newpolicy->policydb, secclass_map,
2300 &newpolicy->map);
2301 if (rc)
2302 goto err_policydb;
2303
2304 rc = policydb_load_isids(&newpolicy->policydb, newpolicy->sidtab);
2305 if (rc) {
2306 pr_err("SELinux: unable to load the initial SIDs\n");
2307 goto err_mapping;
2308 }
2309
2310 if (!selinux_initialized()) {
2311 /* First policy load, so no need to preserve state from old policy */
2312 load_state->policy = newpolicy;
2313 load_state->convert_data = NULL;
2314 return 0;
2315 }
2316
2317 oldpolicy = rcu_dereference_protected(state->policy,
2318 lockdep_is_held(&state->policy_mutex));
2319
2320 /* Preserve active boolean values from the old policy */
2321 rc = security_preserve_bools(oldpolicy, newpolicy);
2322 if (rc) {
2323 pr_err("SELinux: unable to preserve booleans\n");
2324 goto err_free_isids;
2325 }
2326
2327 /*
2328 * Convert the internal representations of contexts
2329 * in the new SID table.
2330 */
2331
2332 convert_data = kmalloc(sizeof(*convert_data), GFP_KERNEL);
2333 if (!convert_data) {
2334 rc = -ENOMEM;
2335 goto err_free_isids;
2336 }
2337
2338 convert_data->args.oldp = &oldpolicy->policydb;
2339 convert_data->args.newp = &newpolicy->policydb;
2340
2341 convert_data->sidtab_params.args = &convert_data->args;
2342 convert_data->sidtab_params.target = newpolicy->sidtab;
2343
2344 rc = sidtab_convert(oldpolicy->sidtab, &convert_data->sidtab_params);
2345 if (rc) {
2346 pr_err("SELinux: unable to convert the internal"
2347 " representation of contexts in the new SID"
2348 " table\n");
2349 goto err_free_convert_data;
2350 }
2351
2352 load_state->policy = newpolicy;
2353 load_state->convert_data = convert_data;
2354 return 0;
2355
2356err_free_convert_data:
2357 kfree(convert_data);
2358err_free_isids:
2359 sidtab_destroy(newpolicy->sidtab);
2360err_mapping:
2361 kfree(newpolicy->map.mapping);
2362err_policydb:
2363 policydb_destroy(&newpolicy->policydb);
2364err_sidtab:
2365 kfree(newpolicy->sidtab);
2366err_policy:
2367 kfree(newpolicy);
2368
2369 return rc;
2370}
2371
2372/**
2373 * ocontext_to_sid - Helper to safely get sid for an ocontext
2374 * @sidtab: SID table
2375 * @c: ocontext structure
2376 * @index: index of the context entry (0 or 1)
2377 * @out_sid: pointer to the resulting SID value
2378 *
2379 * For all ocontexts except OCON_ISID the SID fields are populated
2380 * on-demand when needed. Since updating the SID value is an SMP-sensitive
2381 * operation, this helper must be used to do that safely.
2382 *
2383 * WARNING: This function may return -ESTALE, indicating that the caller
2384 * must retry the operation after re-acquiring the policy pointer!
2385 */
2386static int ocontext_to_sid(struct sidtab *sidtab, struct ocontext *c,
2387 size_t index, u32 *out_sid)
2388{
2389 int rc;
2390 u32 sid;
2391
2392 /* Ensure the associated sidtab entry is visible to this thread. */
2393 sid = smp_load_acquire(&c->sid[index]);
2394 if (!sid) {
2395 rc = sidtab_context_to_sid(sidtab, &c->context[index], &sid);
2396 if (rc)
2397 return rc;
2398
2399 /*
2400 * Ensure the new sidtab entry is visible to other threads
2401 * when they see the SID.
2402 */
2403 smp_store_release(&c->sid[index], sid);
2404 }
2405 *out_sid = sid;
2406 return 0;
2407}
2408
2409/**
2410 * security_port_sid - Obtain the SID for a port.
2411 * @protocol: protocol number
2412 * @port: port number
2413 * @out_sid: security identifier
2414 */
2415int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
2416{
2417 struct selinux_policy *policy;
2418 struct policydb *policydb;
2419 struct sidtab *sidtab;
2420 struct ocontext *c;
2421 int rc;
2422
2423 if (!selinux_initialized()) {
2424 *out_sid = SECINITSID_PORT;
2425 return 0;
2426 }
2427
2428retry:
2429 rc = 0;
2430 rcu_read_lock();
2431 policy = rcu_dereference(selinux_state.policy);
2432 policydb = &policy->policydb;
2433 sidtab = policy->sidtab;
2434
2435 c = policydb->ocontexts[OCON_PORT];
2436 while (c) {
2437 if (c->u.port.protocol == protocol &&
2438 c->u.port.low_port <= port &&
2439 c->u.port.high_port >= port)
2440 break;
2441 c = c->next;
2442 }
2443
2444 if (c) {
2445 rc = ocontext_to_sid(sidtab, c, 0, out_sid);
2446 if (rc == -ESTALE) {
2447 rcu_read_unlock();
2448 goto retry;
2449 }
2450 if (rc)
2451 goto out;
2452 } else {
2453 *out_sid = SECINITSID_PORT;
2454 }
2455
2456out:
2457 rcu_read_unlock();
2458 return rc;
2459}
2460
2461/**
2462 * security_ib_pkey_sid - Obtain the SID for a pkey.
2463 * @subnet_prefix: Subnet Prefix
2464 * @pkey_num: pkey number
2465 * @out_sid: security identifier
2466 */
2467int security_ib_pkey_sid(u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2468{
2469 struct selinux_policy *policy;
2470 struct policydb *policydb;
2471 struct sidtab *sidtab;
2472 struct ocontext *c;
2473 int rc;
2474
2475 if (!selinux_initialized()) {
2476 *out_sid = SECINITSID_UNLABELED;
2477 return 0;
2478 }
2479
2480retry:
2481 rc = 0;
2482 rcu_read_lock();
2483 policy = rcu_dereference(selinux_state.policy);
2484 policydb = &policy->policydb;
2485 sidtab = policy->sidtab;
2486
2487 c = policydb->ocontexts[OCON_IBPKEY];
2488 while (c) {
2489 if (c->u.ibpkey.low_pkey <= pkey_num &&
2490 c->u.ibpkey.high_pkey >= pkey_num &&
2491 c->u.ibpkey.subnet_prefix == subnet_prefix)
2492 break;
2493
2494 c = c->next;
2495 }
2496
2497 if (c) {
2498 rc = ocontext_to_sid(sidtab, c, 0, out_sid);
2499 if (rc == -ESTALE) {
2500 rcu_read_unlock();
2501 goto retry;
2502 }
2503 if (rc)
2504 goto out;
2505 } else
2506 *out_sid = SECINITSID_UNLABELED;
2507
2508out:
2509 rcu_read_unlock();
2510 return rc;
2511}
2512
2513/**
2514 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2515 * @dev_name: device name
2516 * @port_num: port number
2517 * @out_sid: security identifier
2518 */
2519int security_ib_endport_sid(const char *dev_name, u8 port_num, u32 *out_sid)
2520{
2521 struct selinux_policy *policy;
2522 struct policydb *policydb;
2523 struct sidtab *sidtab;
2524 struct ocontext *c;
2525 int rc;
2526
2527 if (!selinux_initialized()) {
2528 *out_sid = SECINITSID_UNLABELED;
2529 return 0;
2530 }
2531
2532retry:
2533 rc = 0;
2534 rcu_read_lock();
2535 policy = rcu_dereference(selinux_state.policy);
2536 policydb = &policy->policydb;
2537 sidtab = policy->sidtab;
2538
2539 c = policydb->ocontexts[OCON_IBENDPORT];
2540 while (c) {
2541 if (c->u.ibendport.port == port_num &&
2542 !strncmp(c->u.ibendport.dev_name,
2543 dev_name,
2544 IB_DEVICE_NAME_MAX))
2545 break;
2546
2547 c = c->next;
2548 }
2549
2550 if (c) {
2551 rc = ocontext_to_sid(sidtab, c, 0, out_sid);
2552 if (rc == -ESTALE) {
2553 rcu_read_unlock();
2554 goto retry;
2555 }
2556 if (rc)
2557 goto out;
2558 } else
2559 *out_sid = SECINITSID_UNLABELED;
2560
2561out:
2562 rcu_read_unlock();
2563 return rc;
2564}
2565
2566/**
2567 * security_netif_sid - Obtain the SID for a network interface.
2568 * @name: interface name
2569 * @if_sid: interface SID
2570 */
2571int security_netif_sid(char *name, u32 *if_sid)
2572{
2573 struct selinux_policy *policy;
2574 struct policydb *policydb;
2575 struct sidtab *sidtab;
2576 int rc;
2577 struct ocontext *c;
2578
2579 if (!selinux_initialized()) {
2580 *if_sid = SECINITSID_NETIF;
2581 return 0;
2582 }
2583
2584retry:
2585 rc = 0;
2586 rcu_read_lock();
2587 policy = rcu_dereference(selinux_state.policy);
2588 policydb = &policy->policydb;
2589 sidtab = policy->sidtab;
2590
2591 c = policydb->ocontexts[OCON_NETIF];
2592 while (c) {
2593 if (strcmp(name, c->u.name) == 0)
2594 break;
2595 c = c->next;
2596 }
2597
2598 if (c) {
2599 rc = ocontext_to_sid(sidtab, c, 0, if_sid);
2600 if (rc == -ESTALE) {
2601 rcu_read_unlock();
2602 goto retry;
2603 }
2604 if (rc)
2605 goto out;
2606 } else
2607 *if_sid = SECINITSID_NETIF;
2608
2609out:
2610 rcu_read_unlock();
2611 return rc;
2612}
2613
2614static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2615{
2616 int i, fail = 0;
2617
2618 for (i = 0; i < 4; i++)
2619 if (addr[i] != (input[i] & mask[i])) {
2620 fail = 1;
2621 break;
2622 }
2623
2624 return !fail;
2625}
2626
2627/**
2628 * security_node_sid - Obtain the SID for a node (host).
2629 * @domain: communication domain aka address family
2630 * @addrp: address
2631 * @addrlen: address length in bytes
2632 * @out_sid: security identifier
2633 */
2634int security_node_sid(u16 domain,
2635 void *addrp,
2636 u32 addrlen,
2637 u32 *out_sid)
2638{
2639 struct selinux_policy *policy;
2640 struct policydb *policydb;
2641 struct sidtab *sidtab;
2642 int rc;
2643 struct ocontext *c;
2644
2645 if (!selinux_initialized()) {
2646 *out_sid = SECINITSID_NODE;
2647 return 0;
2648 }
2649
2650retry:
2651 rcu_read_lock();
2652 policy = rcu_dereference(selinux_state.policy);
2653 policydb = &policy->policydb;
2654 sidtab = policy->sidtab;
2655
2656 switch (domain) {
2657 case AF_INET: {
2658 u32 addr;
2659
2660 rc = -EINVAL;
2661 if (addrlen != sizeof(u32))
2662 goto out;
2663
2664 addr = *((u32 *)addrp);
2665
2666 c = policydb->ocontexts[OCON_NODE];
2667 while (c) {
2668 if (c->u.node.addr == (addr & c->u.node.mask))
2669 break;
2670 c = c->next;
2671 }
2672 break;
2673 }
2674
2675 case AF_INET6:
2676 rc = -EINVAL;
2677 if (addrlen != sizeof(u64) * 2)
2678 goto out;
2679 c = policydb->ocontexts[OCON_NODE6];
2680 while (c) {
2681 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2682 c->u.node6.mask))
2683 break;
2684 c = c->next;
2685 }
2686 break;
2687
2688 default:
2689 rc = 0;
2690 *out_sid = SECINITSID_NODE;
2691 goto out;
2692 }
2693
2694 if (c) {
2695 rc = ocontext_to_sid(sidtab, c, 0, out_sid);
2696 if (rc == -ESTALE) {
2697 rcu_read_unlock();
2698 goto retry;
2699 }
2700 if (rc)
2701 goto out;
2702 } else {
2703 *out_sid = SECINITSID_NODE;
2704 }
2705
2706 rc = 0;
2707out:
2708 rcu_read_unlock();
2709 return rc;
2710}
2711
2712#define SIDS_NEL 25
2713
2714/**
2715 * security_get_user_sids - Obtain reachable SIDs for a user.
2716 * @fromsid: starting SID
2717 * @username: username
2718 * @sids: array of reachable SIDs for user
2719 * @nel: number of elements in @sids
2720 *
2721 * Generate the set of SIDs for legal security contexts
2722 * for a given user that can be reached by @fromsid.
2723 * Set *@sids to point to a dynamically allocated
2724 * array containing the set of SIDs. Set *@nel to the
2725 * number of elements in the array.
2726 */
2727
2728int security_get_user_sids(u32 fromsid,
2729 char *username,
2730 u32 **sids,
2731 u32 *nel)
2732{
2733 struct selinux_policy *policy;
2734 struct policydb *policydb;
2735 struct sidtab *sidtab;
2736 struct context *fromcon, usercon;
2737 u32 *mysids = NULL, *mysids2, sid;
2738 u32 i, j, mynel, maxnel = SIDS_NEL;
2739 struct user_datum *user;
2740 struct role_datum *role;
2741 struct ebitmap_node *rnode, *tnode;
2742 int rc;
2743
2744 *sids = NULL;
2745 *nel = 0;
2746
2747 if (!selinux_initialized())
2748 return 0;
2749
2750 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_KERNEL);
2751 if (!mysids)
2752 return -ENOMEM;
2753
2754retry:
2755 mynel = 0;
2756 rcu_read_lock();
2757 policy = rcu_dereference(selinux_state.policy);
2758 policydb = &policy->policydb;
2759 sidtab = policy->sidtab;
2760
2761 context_init(&usercon);
2762
2763 rc = -EINVAL;
2764 fromcon = sidtab_search(sidtab, fromsid);
2765 if (!fromcon)
2766 goto out_unlock;
2767
2768 rc = -EINVAL;
2769 user = symtab_search(&policydb->p_users, username);
2770 if (!user)
2771 goto out_unlock;
2772
2773 usercon.user = user->value;
2774
2775 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2776 role = policydb->role_val_to_struct[i];
2777 usercon.role = i + 1;
2778 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2779 usercon.type = j + 1;
2780
2781 if (mls_setup_user_range(policydb, fromcon, user,
2782 &usercon))
2783 continue;
2784
2785 rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2786 if (rc == -ESTALE) {
2787 rcu_read_unlock();
2788 goto retry;
2789 }
2790 if (rc)
2791 goto out_unlock;
2792 if (mynel < maxnel) {
2793 mysids[mynel++] = sid;
2794 } else {
2795 rc = -ENOMEM;
2796 maxnel += SIDS_NEL;
2797 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2798 if (!mysids2)
2799 goto out_unlock;
2800 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2801 kfree(mysids);
2802 mysids = mysids2;
2803 mysids[mynel++] = sid;
2804 }
2805 }
2806 }
2807 rc = 0;
2808out_unlock:
2809 rcu_read_unlock();
2810 if (rc || !mynel) {
2811 kfree(mysids);
2812 return rc;
2813 }
2814
2815 rc = -ENOMEM;
2816 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2817 if (!mysids2) {
2818 kfree(mysids);
2819 return rc;
2820 }
2821 for (i = 0, j = 0; i < mynel; i++) {
2822 struct av_decision dummy_avd;
2823 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2824 SECCLASS_PROCESS, /* kernel value */
2825 PROCESS__TRANSITION, AVC_STRICT,
2826 &dummy_avd);
2827 if (!rc)
2828 mysids2[j++] = mysids[i];
2829 cond_resched();
2830 }
2831 kfree(mysids);
2832 *sids = mysids2;
2833 *nel = j;
2834 return 0;
2835}
2836
2837/**
2838 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2839 * @policy: policy
2840 * @fstype: filesystem type
2841 * @path: path from root of mount
2842 * @orig_sclass: file security class
2843 * @sid: SID for path
2844 *
2845 * Obtain a SID to use for a file in a filesystem that
2846 * cannot support xattr or use a fixed labeling behavior like
2847 * transition SIDs or task SIDs.
2848 *
2849 * WARNING: This function may return -ESTALE, indicating that the caller
2850 * must retry the operation after re-acquiring the policy pointer!
2851 */
2852static inline int __security_genfs_sid(struct selinux_policy *policy,
2853 const char *fstype,
2854 const char *path,
2855 u16 orig_sclass,
2856 u32 *sid)
2857{
2858 struct policydb *policydb = &policy->policydb;
2859 struct sidtab *sidtab = policy->sidtab;
2860 u16 sclass;
2861 struct genfs *genfs;
2862 struct ocontext *c;
2863 int cmp = 0;
2864
2865 while (path[0] == '/' && path[1] == '/')
2866 path++;
2867
2868 sclass = unmap_class(&policy->map, orig_sclass);
2869 *sid = SECINITSID_UNLABELED;
2870
2871 for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2872 cmp = strcmp(fstype, genfs->fstype);
2873 if (cmp <= 0)
2874 break;
2875 }
2876
2877 if (!genfs || cmp)
2878 return -ENOENT;
2879
2880 for (c = genfs->head; c; c = c->next) {
2881 size_t len = strlen(c->u.name);
2882 if ((!c->v.sclass || sclass == c->v.sclass) &&
2883 (strncmp(c->u.name, path, len) == 0))
2884 break;
2885 }
2886
2887 if (!c)
2888 return -ENOENT;
2889
2890 return ocontext_to_sid(sidtab, c, 0, sid);
2891}
2892
2893/**
2894 * security_genfs_sid - Obtain a SID for a file in a filesystem
2895 * @fstype: filesystem type
2896 * @path: path from root of mount
2897 * @orig_sclass: file security class
2898 * @sid: SID for path
2899 *
2900 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2901 * it afterward.
2902 */
2903int security_genfs_sid(const char *fstype,
2904 const char *path,
2905 u16 orig_sclass,
2906 u32 *sid)
2907{
2908 struct selinux_policy *policy;
2909 int retval;
2910
2911 if (!selinux_initialized()) {
2912 *sid = SECINITSID_UNLABELED;
2913 return 0;
2914 }
2915
2916 do {
2917 rcu_read_lock();
2918 policy = rcu_dereference(selinux_state.policy);
2919 retval = __security_genfs_sid(policy, fstype, path,
2920 orig_sclass, sid);
2921 rcu_read_unlock();
2922 } while (retval == -ESTALE);
2923 return retval;
2924}
2925
2926int selinux_policy_genfs_sid(struct selinux_policy *policy,
2927 const char *fstype,
2928 const char *path,
2929 u16 orig_sclass,
2930 u32 *sid)
2931{
2932 /* no lock required, policy is not yet accessible by other threads */
2933 return __security_genfs_sid(policy, fstype, path, orig_sclass, sid);
2934}
2935
2936/**
2937 * security_fs_use - Determine how to handle labeling for a filesystem.
2938 * @sb: superblock in question
2939 */
2940int security_fs_use(struct super_block *sb)
2941{
2942 struct selinux_policy *policy;
2943 struct policydb *policydb;
2944 struct sidtab *sidtab;
2945 int rc;
2946 struct ocontext *c;
2947 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2948 const char *fstype = sb->s_type->name;
2949
2950 if (!selinux_initialized()) {
2951 sbsec->behavior = SECURITY_FS_USE_NONE;
2952 sbsec->sid = SECINITSID_UNLABELED;
2953 return 0;
2954 }
2955
2956retry:
2957 rcu_read_lock();
2958 policy = rcu_dereference(selinux_state.policy);
2959 policydb = &policy->policydb;
2960 sidtab = policy->sidtab;
2961
2962 c = policydb->ocontexts[OCON_FSUSE];
2963 while (c) {
2964 if (strcmp(fstype, c->u.name) == 0)
2965 break;
2966 c = c->next;
2967 }
2968
2969 if (c) {
2970 sbsec->behavior = c->v.behavior;
2971 rc = ocontext_to_sid(sidtab, c, 0, &sbsec->sid);
2972 if (rc == -ESTALE) {
2973 rcu_read_unlock();
2974 goto retry;
2975 }
2976 if (rc)
2977 goto out;
2978 } else {
2979 rc = __security_genfs_sid(policy, fstype, "/",
2980 SECCLASS_DIR, &sbsec->sid);
2981 if (rc == -ESTALE) {
2982 rcu_read_unlock();
2983 goto retry;
2984 }
2985 if (rc) {
2986 sbsec->behavior = SECURITY_FS_USE_NONE;
2987 rc = 0;
2988 } else {
2989 sbsec->behavior = SECURITY_FS_USE_GENFS;
2990 }
2991 }
2992
2993out:
2994 rcu_read_unlock();
2995 return rc;
2996}
2997
2998int security_get_bools(struct selinux_policy *policy,
2999 u32 *len, char ***names, int **values)
3000{
3001 struct policydb *policydb;
3002 u32 i;
3003 int rc;
3004
3005 policydb = &policy->policydb;
3006
3007 *names = NULL;
3008 *values = NULL;
3009
3010 rc = 0;
3011 *len = policydb->p_bools.nprim;
3012 if (!*len)
3013 goto out;
3014
3015 rc = -ENOMEM;
3016 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
3017 if (!*names)
3018 goto err;
3019
3020 rc = -ENOMEM;
3021 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
3022 if (!*values)
3023 goto err;
3024
3025 for (i = 0; i < *len; i++) {
3026 (*values)[i] = policydb->bool_val_to_struct[i]->state;
3027
3028 rc = -ENOMEM;
3029 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
3030 GFP_ATOMIC);
3031 if (!(*names)[i])
3032 goto err;
3033 }
3034 rc = 0;
3035out:
3036 return rc;
3037err:
3038 if (*names) {
3039 for (i = 0; i < *len; i++)
3040 kfree((*names)[i]);
3041 kfree(*names);
3042 }
3043 kfree(*values);
3044 *len = 0;
3045 *names = NULL;
3046 *values = NULL;
3047 goto out;
3048}
3049
3050
3051int security_set_bools(u32 len, int *values)
3052{
3053 struct selinux_state *state = &selinux_state;
3054 struct selinux_policy *newpolicy, *oldpolicy;
3055 int rc;
3056 u32 i, seqno = 0;
3057
3058 if (!selinux_initialized())
3059 return -EINVAL;
3060
3061 oldpolicy = rcu_dereference_protected(state->policy,
3062 lockdep_is_held(&state->policy_mutex));
3063
3064 /* Consistency check on number of booleans, should never fail */
3065 if (WARN_ON(len != oldpolicy->policydb.p_bools.nprim))
3066 return -EINVAL;
3067
3068 newpolicy = kmemdup(oldpolicy, sizeof(*newpolicy), GFP_KERNEL);
3069 if (!newpolicy)
3070 return -ENOMEM;
3071
3072 /*
3073 * Deep copy only the parts of the policydb that might be
3074 * modified as a result of changing booleans.
3075 */
3076 rc = cond_policydb_dup(&newpolicy->policydb, &oldpolicy->policydb);
3077 if (rc) {
3078 kfree(newpolicy);
3079 return -ENOMEM;
3080 }
3081
3082 /* Update the boolean states in the copy */
3083 for (i = 0; i < len; i++) {
3084 int new_state = !!values[i];
3085 int old_state = newpolicy->policydb.bool_val_to_struct[i]->state;
3086
3087 if (new_state != old_state) {
3088 audit_log(audit_context(), GFP_ATOMIC,
3089 AUDIT_MAC_CONFIG_CHANGE,
3090 "bool=%s val=%d old_val=%d auid=%u ses=%u",
3091 sym_name(&newpolicy->policydb, SYM_BOOLS, i),
3092 new_state,
3093 old_state,
3094 from_kuid(&init_user_ns, audit_get_loginuid(current)),
3095 audit_get_sessionid(current));
3096 newpolicy->policydb.bool_val_to_struct[i]->state = new_state;
3097 }
3098 }
3099
3100 /* Re-evaluate the conditional rules in the copy */
3101 evaluate_cond_nodes(&newpolicy->policydb);
3102
3103 /* Set latest granting seqno for new policy */
3104 newpolicy->latest_granting = oldpolicy->latest_granting + 1;
3105 seqno = newpolicy->latest_granting;
3106
3107 /* Install the new policy */
3108 rcu_assign_pointer(state->policy, newpolicy);
3109
3110 /*
3111 * Free the conditional portions of the old policydb
3112 * that were copied for the new policy, and the oldpolicy
3113 * structure itself but not what it references.
3114 */
3115 synchronize_rcu();
3116 selinux_policy_cond_free(oldpolicy);
3117
3118 /* Notify others of the policy change */
3119 selinux_notify_policy_change(seqno);
3120 return 0;
3121}
3122
3123int security_get_bool_value(u32 index)
3124{
3125 struct selinux_policy *policy;
3126 struct policydb *policydb;
3127 int rc;
3128 u32 len;
3129
3130 if (!selinux_initialized())
3131 return 0;
3132
3133 rcu_read_lock();
3134 policy = rcu_dereference(selinux_state.policy);
3135 policydb = &policy->policydb;
3136
3137 rc = -EFAULT;
3138 len = policydb->p_bools.nprim;
3139 if (index >= len)
3140 goto out;
3141
3142 rc = policydb->bool_val_to_struct[index]->state;
3143out:
3144 rcu_read_unlock();
3145 return rc;
3146}
3147
3148static int security_preserve_bools(struct selinux_policy *oldpolicy,
3149 struct selinux_policy *newpolicy)
3150{
3151 int rc, *bvalues = NULL;
3152 char **bnames = NULL;
3153 struct cond_bool_datum *booldatum;
3154 u32 i, nbools = 0;
3155
3156 rc = security_get_bools(oldpolicy, &nbools, &bnames, &bvalues);
3157 if (rc)
3158 goto out;
3159 for (i = 0; i < nbools; i++) {
3160 booldatum = symtab_search(&newpolicy->policydb.p_bools,
3161 bnames[i]);
3162 if (booldatum)
3163 booldatum->state = bvalues[i];
3164 }
3165 evaluate_cond_nodes(&newpolicy->policydb);
3166
3167out:
3168 if (bnames) {
3169 for (i = 0; i < nbools; i++)
3170 kfree(bnames[i]);
3171 }
3172 kfree(bnames);
3173 kfree(bvalues);
3174 return rc;
3175}
3176
3177/*
3178 * security_sid_mls_copy() - computes a new sid based on the given
3179 * sid and the mls portion of mls_sid.
3180 */
3181int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
3182{
3183 struct selinux_policy *policy;
3184 struct policydb *policydb;
3185 struct sidtab *sidtab;
3186 struct context *context1;
3187 struct context *context2;
3188 struct context newcon;
3189 char *s;
3190 u32 len;
3191 int rc;
3192
3193 if (!selinux_initialized()) {
3194 *new_sid = sid;
3195 return 0;
3196 }
3197
3198retry:
3199 rc = 0;
3200 context_init(&newcon);
3201
3202 rcu_read_lock();
3203 policy = rcu_dereference(selinux_state.policy);
3204 policydb = &policy->policydb;
3205 sidtab = policy->sidtab;
3206
3207 if (!policydb->mls_enabled) {
3208 *new_sid = sid;
3209 goto out_unlock;
3210 }
3211
3212 rc = -EINVAL;
3213 context1 = sidtab_search(sidtab, sid);
3214 if (!context1) {
3215 pr_err("SELinux: %s: unrecognized SID %d\n",
3216 __func__, sid);
3217 goto out_unlock;
3218 }
3219
3220 rc = -EINVAL;
3221 context2 = sidtab_search(sidtab, mls_sid);
3222 if (!context2) {
3223 pr_err("SELinux: %s: unrecognized SID %d\n",
3224 __func__, mls_sid);
3225 goto out_unlock;
3226 }
3227
3228 newcon.user = context1->user;
3229 newcon.role = context1->role;
3230 newcon.type = context1->type;
3231 rc = mls_context_cpy(&newcon, context2);
3232 if (rc)
3233 goto out_unlock;
3234
3235 /* Check the validity of the new context. */
3236 if (!policydb_context_isvalid(policydb, &newcon)) {
3237 rc = convert_context_handle_invalid_context(policydb,
3238 &newcon);
3239 if (rc) {
3240 if (!context_struct_to_string(policydb, &newcon, &s,
3241 &len)) {
3242 struct audit_buffer *ab;
3243
3244 ab = audit_log_start(audit_context(),
3245 GFP_ATOMIC,
3246 AUDIT_SELINUX_ERR);
3247 audit_log_format(ab,
3248 "op=security_sid_mls_copy invalid_context=");
3249 /* don't record NUL with untrusted strings */
3250 audit_log_n_untrustedstring(ab, s, len - 1);
3251 audit_log_end(ab);
3252 kfree(s);
3253 }
3254 goto out_unlock;
3255 }
3256 }
3257 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3258 if (rc == -ESTALE) {
3259 rcu_read_unlock();
3260 context_destroy(&newcon);
3261 goto retry;
3262 }
3263out_unlock:
3264 rcu_read_unlock();
3265 context_destroy(&newcon);
3266 return rc;
3267}
3268
3269/**
3270 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3271 * @nlbl_sid: NetLabel SID
3272 * @nlbl_type: NetLabel labeling protocol type
3273 * @xfrm_sid: XFRM SID
3274 * @peer_sid: network peer sid
3275 *
3276 * Description:
3277 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3278 * resolved into a single SID it is returned via @peer_sid and the function
3279 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3280 * returns a negative value. A table summarizing the behavior is below:
3281 *
3282 * | function return | @sid
3283 * ------------------------------+-----------------+-----------------
3284 * no peer labels | 0 | SECSID_NULL
3285 * single peer label | 0 | <peer_label>
3286 * multiple, consistent labels | 0 | <peer_label>
3287 * multiple, inconsistent labels | -<errno> | SECSID_NULL
3288 *
3289 */
3290int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
3291 u32 xfrm_sid,
3292 u32 *peer_sid)
3293{
3294 struct selinux_policy *policy;
3295 struct policydb *policydb;
3296 struct sidtab *sidtab;
3297 int rc;
3298 struct context *nlbl_ctx;
3299 struct context *xfrm_ctx;
3300
3301 *peer_sid = SECSID_NULL;
3302
3303 /* handle the common (which also happens to be the set of easy) cases
3304 * right away, these two if statements catch everything involving a
3305 * single or absent peer SID/label */
3306 if (xfrm_sid == SECSID_NULL) {
3307 *peer_sid = nlbl_sid;
3308 return 0;
3309 }
3310 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3311 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3312 * is present */
3313 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3314 *peer_sid = xfrm_sid;
3315 return 0;
3316 }
3317
3318 if (!selinux_initialized())
3319 return 0;
3320
3321 rcu_read_lock();
3322 policy = rcu_dereference(selinux_state.policy);
3323 policydb = &policy->policydb;
3324 sidtab = policy->sidtab;
3325
3326 /*
3327 * We don't need to check initialized here since the only way both
3328 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3329 * security server was initialized and state->initialized was true.
3330 */
3331 if (!policydb->mls_enabled) {
3332 rc = 0;
3333 goto out;
3334 }
3335
3336 rc = -EINVAL;
3337 nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3338 if (!nlbl_ctx) {
3339 pr_err("SELinux: %s: unrecognized SID %d\n",
3340 __func__, nlbl_sid);
3341 goto out;
3342 }
3343 rc = -EINVAL;
3344 xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3345 if (!xfrm_ctx) {
3346 pr_err("SELinux: %s: unrecognized SID %d\n",
3347 __func__, xfrm_sid);
3348 goto out;
3349 }
3350 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3351 if (rc)
3352 goto out;
3353
3354 /* at present NetLabel SIDs/labels really only carry MLS
3355 * information so if the MLS portion of the NetLabel SID
3356 * matches the MLS portion of the labeled XFRM SID/label
3357 * then pass along the XFRM SID as it is the most
3358 * expressive */
3359 *peer_sid = xfrm_sid;
3360out:
3361 rcu_read_unlock();
3362 return rc;
3363}
3364
3365static int get_classes_callback(void *k, void *d, void *args)
3366{
3367 struct class_datum *datum = d;
3368 char *name = k, **classes = args;
3369 u32 value = datum->value - 1;
3370
3371 classes[value] = kstrdup(name, GFP_ATOMIC);
3372 if (!classes[value])
3373 return -ENOMEM;
3374
3375 return 0;
3376}
3377
3378int security_get_classes(struct selinux_policy *policy,
3379 char ***classes, u32 *nclasses)
3380{
3381 struct policydb *policydb;
3382 int rc;
3383
3384 policydb = &policy->policydb;
3385
3386 rc = -ENOMEM;
3387 *nclasses = policydb->p_classes.nprim;
3388 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3389 if (!*classes)
3390 goto out;
3391
3392 rc = hashtab_map(&policydb->p_classes.table, get_classes_callback,
3393 *classes);
3394 if (rc) {
3395 u32 i;
3396
3397 for (i = 0; i < *nclasses; i++)
3398 kfree((*classes)[i]);
3399 kfree(*classes);
3400 }
3401
3402out:
3403 return rc;
3404}
3405
3406static int get_permissions_callback(void *k, void *d, void *args)
3407{
3408 struct perm_datum *datum = d;
3409 char *name = k, **perms = args;
3410 u32 value = datum->value - 1;
3411
3412 perms[value] = kstrdup(name, GFP_ATOMIC);
3413 if (!perms[value])
3414 return -ENOMEM;
3415
3416 return 0;
3417}
3418
3419int security_get_permissions(struct selinux_policy *policy,
3420 const char *class, char ***perms, u32 *nperms)
3421{
3422 struct policydb *policydb;
3423 u32 i;
3424 int rc;
3425 struct class_datum *match;
3426
3427 policydb = &policy->policydb;
3428
3429 rc = -EINVAL;
3430 match = symtab_search(&policydb->p_classes, class);
3431 if (!match) {
3432 pr_err("SELinux: %s: unrecognized class %s\n",
3433 __func__, class);
3434 goto out;
3435 }
3436
3437 rc = -ENOMEM;
3438 *nperms = match->permissions.nprim;
3439 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3440 if (!*perms)
3441 goto out;
3442
3443 if (match->comdatum) {
3444 rc = hashtab_map(&match->comdatum->permissions.table,
3445 get_permissions_callback, *perms);
3446 if (rc)
3447 goto err;
3448 }
3449
3450 rc = hashtab_map(&match->permissions.table, get_permissions_callback,
3451 *perms);
3452 if (rc)
3453 goto err;
3454
3455out:
3456 return rc;
3457
3458err:
3459 for (i = 0; i < *nperms; i++)
3460 kfree((*perms)[i]);
3461 kfree(*perms);
3462 return rc;
3463}
3464
3465int security_get_reject_unknown(void)
3466{
3467 struct selinux_policy *policy;
3468 int value;
3469
3470 if (!selinux_initialized())
3471 return 0;
3472
3473 rcu_read_lock();
3474 policy = rcu_dereference(selinux_state.policy);
3475 value = policy->policydb.reject_unknown;
3476 rcu_read_unlock();
3477 return value;
3478}
3479
3480int security_get_allow_unknown(void)
3481{
3482 struct selinux_policy *policy;
3483 int value;
3484
3485 if (!selinux_initialized())
3486 return 0;
3487
3488 rcu_read_lock();
3489 policy = rcu_dereference(selinux_state.policy);
3490 value = policy->policydb.allow_unknown;
3491 rcu_read_unlock();
3492 return value;
3493}
3494
3495/**
3496 * security_policycap_supported - Check for a specific policy capability
3497 * @req_cap: capability
3498 *
3499 * Description:
3500 * This function queries the currently loaded policy to see if it supports the
3501 * capability specified by @req_cap. Returns true (1) if the capability is
3502 * supported, false (0) if it isn't supported.
3503 *
3504 */
3505int security_policycap_supported(unsigned int req_cap)
3506{
3507 struct selinux_policy *policy;
3508 int rc;
3509
3510 if (!selinux_initialized())
3511 return 0;
3512
3513 rcu_read_lock();
3514 policy = rcu_dereference(selinux_state.policy);
3515 rc = ebitmap_get_bit(&policy->policydb.policycaps, req_cap);
3516 rcu_read_unlock();
3517
3518 return rc;
3519}
3520
3521struct selinux_audit_rule {
3522 u32 au_seqno;
3523 struct context au_ctxt;
3524};
3525
3526void selinux_audit_rule_free(void *vrule)
3527{
3528 struct selinux_audit_rule *rule = vrule;
3529
3530 if (rule) {
3531 context_destroy(&rule->au_ctxt);
3532 kfree(rule);
3533 }
3534}
3535
3536int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule,
3537 gfp_t gfp)
3538{
3539 struct selinux_state *state = &selinux_state;
3540 struct selinux_policy *policy;
3541 struct policydb *policydb;
3542 struct selinux_audit_rule *tmprule;
3543 struct role_datum *roledatum;
3544 struct type_datum *typedatum;
3545 struct user_datum *userdatum;
3546 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3547 int rc = 0;
3548
3549 *rule = NULL;
3550
3551 if (!selinux_initialized())
3552 return -EOPNOTSUPP;
3553
3554 switch (field) {
3555 case AUDIT_SUBJ_USER:
3556 case AUDIT_SUBJ_ROLE:
3557 case AUDIT_SUBJ_TYPE:
3558 case AUDIT_OBJ_USER:
3559 case AUDIT_OBJ_ROLE:
3560 case AUDIT_OBJ_TYPE:
3561 /* only 'equals' and 'not equals' fit user, role, and type */
3562 if (op != Audit_equal && op != Audit_not_equal)
3563 return -EINVAL;
3564 break;
3565 case AUDIT_SUBJ_SEN:
3566 case AUDIT_SUBJ_CLR:
3567 case AUDIT_OBJ_LEV_LOW:
3568 case AUDIT_OBJ_LEV_HIGH:
3569 /* we do not allow a range, indicated by the presence of '-' */
3570 if (strchr(rulestr, '-'))
3571 return -EINVAL;
3572 break;
3573 default:
3574 /* only the above fields are valid */
3575 return -EINVAL;
3576 }
3577
3578 tmprule = kzalloc(sizeof(struct selinux_audit_rule), gfp);
3579 if (!tmprule)
3580 return -ENOMEM;
3581 context_init(&tmprule->au_ctxt);
3582
3583 rcu_read_lock();
3584 policy = rcu_dereference(state->policy);
3585 policydb = &policy->policydb;
3586 tmprule->au_seqno = policy->latest_granting;
3587 switch (field) {
3588 case AUDIT_SUBJ_USER:
3589 case AUDIT_OBJ_USER:
3590 userdatum = symtab_search(&policydb->p_users, rulestr);
3591 if (!userdatum) {
3592 rc = -EINVAL;
3593 goto err;
3594 }
3595 tmprule->au_ctxt.user = userdatum->value;
3596 break;
3597 case AUDIT_SUBJ_ROLE:
3598 case AUDIT_OBJ_ROLE:
3599 roledatum = symtab_search(&policydb->p_roles, rulestr);
3600 if (!roledatum) {
3601 rc = -EINVAL;
3602 goto err;
3603 }
3604 tmprule->au_ctxt.role = roledatum->value;
3605 break;
3606 case AUDIT_SUBJ_TYPE:
3607 case AUDIT_OBJ_TYPE:
3608 typedatum = symtab_search(&policydb->p_types, rulestr);
3609 if (!typedatum) {
3610 rc = -EINVAL;
3611 goto err;
3612 }
3613 tmprule->au_ctxt.type = typedatum->value;
3614 break;
3615 case AUDIT_SUBJ_SEN:
3616 case AUDIT_SUBJ_CLR:
3617 case AUDIT_OBJ_LEV_LOW:
3618 case AUDIT_OBJ_LEV_HIGH:
3619 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3620 GFP_ATOMIC);
3621 if (rc)
3622 goto err;
3623 break;
3624 }
3625 rcu_read_unlock();
3626
3627 *rule = tmprule;
3628 return 0;
3629
3630err:
3631 rcu_read_unlock();
3632 selinux_audit_rule_free(tmprule);
3633 *rule = NULL;
3634 return rc;
3635}
3636
3637/* Check to see if the rule contains any selinux fields */
3638int selinux_audit_rule_known(struct audit_krule *rule)
3639{
3640 u32 i;
3641
3642 for (i = 0; i < rule->field_count; i++) {
3643 struct audit_field *f = &rule->fields[i];
3644 switch (f->type) {
3645 case AUDIT_SUBJ_USER:
3646 case AUDIT_SUBJ_ROLE:
3647 case AUDIT_SUBJ_TYPE:
3648 case AUDIT_SUBJ_SEN:
3649 case AUDIT_SUBJ_CLR:
3650 case AUDIT_OBJ_USER:
3651 case AUDIT_OBJ_ROLE:
3652 case AUDIT_OBJ_TYPE:
3653 case AUDIT_OBJ_LEV_LOW:
3654 case AUDIT_OBJ_LEV_HIGH:
3655 return 1;
3656 }
3657 }
3658
3659 return 0;
3660}
3661
3662int selinux_audit_rule_match(struct lsm_prop *prop, u32 field, u32 op, void *vrule)
3663{
3664 struct selinux_state *state = &selinux_state;
3665 struct selinux_policy *policy;
3666 struct context *ctxt;
3667 struct mls_level *level;
3668 struct selinux_audit_rule *rule = vrule;
3669 int match = 0;
3670
3671 if (unlikely(!rule)) {
3672 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3673 return -ENOENT;
3674 }
3675
3676 if (!selinux_initialized())
3677 return 0;
3678
3679 rcu_read_lock();
3680
3681 policy = rcu_dereference(state->policy);
3682
3683 if (rule->au_seqno < policy->latest_granting) {
3684 match = -ESTALE;
3685 goto out;
3686 }
3687
3688 ctxt = sidtab_search(policy->sidtab, prop->selinux.secid);
3689 if (unlikely(!ctxt)) {
3690 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3691 prop->selinux.secid);
3692 match = -ENOENT;
3693 goto out;
3694 }
3695
3696 /* a field/op pair that is not caught here will simply fall through
3697 without a match */
3698 switch (field) {
3699 case AUDIT_SUBJ_USER:
3700 case AUDIT_OBJ_USER:
3701 switch (op) {
3702 case Audit_equal:
3703 match = (ctxt->user == rule->au_ctxt.user);
3704 break;
3705 case Audit_not_equal:
3706 match = (ctxt->user != rule->au_ctxt.user);
3707 break;
3708 }
3709 break;
3710 case AUDIT_SUBJ_ROLE:
3711 case AUDIT_OBJ_ROLE:
3712 switch (op) {
3713 case Audit_equal:
3714 match = (ctxt->role == rule->au_ctxt.role);
3715 break;
3716 case Audit_not_equal:
3717 match = (ctxt->role != rule->au_ctxt.role);
3718 break;
3719 }
3720 break;
3721 case AUDIT_SUBJ_TYPE:
3722 case AUDIT_OBJ_TYPE:
3723 switch (op) {
3724 case Audit_equal:
3725 match = (ctxt->type == rule->au_ctxt.type);
3726 break;
3727 case Audit_not_equal:
3728 match = (ctxt->type != rule->au_ctxt.type);
3729 break;
3730 }
3731 break;
3732 case AUDIT_SUBJ_SEN:
3733 case AUDIT_SUBJ_CLR:
3734 case AUDIT_OBJ_LEV_LOW:
3735 case AUDIT_OBJ_LEV_HIGH:
3736 level = ((field == AUDIT_SUBJ_SEN ||
3737 field == AUDIT_OBJ_LEV_LOW) ?
3738 &ctxt->range.level[0] : &ctxt->range.level[1]);
3739 switch (op) {
3740 case Audit_equal:
3741 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3742 level);
3743 break;
3744 case Audit_not_equal:
3745 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3746 level);
3747 break;
3748 case Audit_lt:
3749 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3750 level) &&
3751 !mls_level_eq(&rule->au_ctxt.range.level[0],
3752 level));
3753 break;
3754 case Audit_le:
3755 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3756 level);
3757 break;
3758 case Audit_gt:
3759 match = (mls_level_dom(level,
3760 &rule->au_ctxt.range.level[0]) &&
3761 !mls_level_eq(level,
3762 &rule->au_ctxt.range.level[0]));
3763 break;
3764 case Audit_ge:
3765 match = mls_level_dom(level,
3766 &rule->au_ctxt.range.level[0]);
3767 break;
3768 }
3769 }
3770
3771out:
3772 rcu_read_unlock();
3773 return match;
3774}
3775
3776static int aurule_avc_callback(u32 event)
3777{
3778 if (event == AVC_CALLBACK_RESET)
3779 return audit_update_lsm_rules();
3780 return 0;
3781}
3782
3783static int __init aurule_init(void)
3784{
3785 int err;
3786
3787 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3788 if (err)
3789 panic("avc_add_callback() failed, error %d\n", err);
3790
3791 return err;
3792}
3793__initcall(aurule_init);
3794
3795#ifdef CONFIG_NETLABEL
3796/**
3797 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3798 * @secattr: the NetLabel packet security attributes
3799 * @sid: the SELinux SID
3800 *
3801 * Description:
3802 * Attempt to cache the context in @ctx, which was derived from the packet in
3803 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3804 * already been initialized.
3805 *
3806 */
3807static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3808 u32 sid)
3809{
3810 u32 *sid_cache;
3811
3812 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3813 if (sid_cache == NULL)
3814 return;
3815 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3816 if (secattr->cache == NULL) {
3817 kfree(sid_cache);
3818 return;
3819 }
3820
3821 *sid_cache = sid;
3822 secattr->cache->free = kfree;
3823 secattr->cache->data = sid_cache;
3824 secattr->flags |= NETLBL_SECATTR_CACHE;
3825}
3826
3827/**
3828 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3829 * @secattr: the NetLabel packet security attributes
3830 * @sid: the SELinux SID
3831 *
3832 * Description:
3833 * Convert the given NetLabel security attributes in @secattr into a
3834 * SELinux SID. If the @secattr field does not contain a full SELinux
3835 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3836 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3837 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3838 * conversion for future lookups. Returns zero on success, negative values on
3839 * failure.
3840 *
3841 */
3842int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3843 u32 *sid)
3844{
3845 struct selinux_policy *policy;
3846 struct policydb *policydb;
3847 struct sidtab *sidtab;
3848 int rc;
3849 struct context *ctx;
3850 struct context ctx_new;
3851
3852 if (!selinux_initialized()) {
3853 *sid = SECSID_NULL;
3854 return 0;
3855 }
3856
3857retry:
3858 rc = 0;
3859 rcu_read_lock();
3860 policy = rcu_dereference(selinux_state.policy);
3861 policydb = &policy->policydb;
3862 sidtab = policy->sidtab;
3863
3864 if (secattr->flags & NETLBL_SECATTR_CACHE)
3865 *sid = *(u32 *)secattr->cache->data;
3866 else if (secattr->flags & NETLBL_SECATTR_SECID)
3867 *sid = secattr->attr.secid;
3868 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3869 rc = -EIDRM;
3870 ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3871 if (ctx == NULL)
3872 goto out;
3873
3874 context_init(&ctx_new);
3875 ctx_new.user = ctx->user;
3876 ctx_new.role = ctx->role;
3877 ctx_new.type = ctx->type;
3878 mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3879 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3880 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3881 if (rc)
3882 goto out;
3883 }
3884 rc = -EIDRM;
3885 if (!mls_context_isvalid(policydb, &ctx_new)) {
3886 ebitmap_destroy(&ctx_new.range.level[0].cat);
3887 goto out;
3888 }
3889
3890 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3891 ebitmap_destroy(&ctx_new.range.level[0].cat);
3892 if (rc == -ESTALE) {
3893 rcu_read_unlock();
3894 goto retry;
3895 }
3896 if (rc)
3897 goto out;
3898
3899 security_netlbl_cache_add(secattr, *sid);
3900 } else
3901 *sid = SECSID_NULL;
3902
3903out:
3904 rcu_read_unlock();
3905 return rc;
3906}
3907
3908/**
3909 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3910 * @sid: the SELinux SID
3911 * @secattr: the NetLabel packet security attributes
3912 *
3913 * Description:
3914 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3915 * Returns zero on success, negative values on failure.
3916 *
3917 */
3918int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3919{
3920 struct selinux_policy *policy;
3921 struct policydb *policydb;
3922 int rc;
3923 struct context *ctx;
3924
3925 if (!selinux_initialized())
3926 return 0;
3927
3928 rcu_read_lock();
3929 policy = rcu_dereference(selinux_state.policy);
3930 policydb = &policy->policydb;
3931
3932 rc = -ENOENT;
3933 ctx = sidtab_search(policy->sidtab, sid);
3934 if (ctx == NULL)
3935 goto out;
3936
3937 rc = -ENOMEM;
3938 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3939 GFP_ATOMIC);
3940 if (secattr->domain == NULL)
3941 goto out;
3942
3943 secattr->attr.secid = sid;
3944 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3945 mls_export_netlbl_lvl(policydb, ctx, secattr);
3946 rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3947out:
3948 rcu_read_unlock();
3949 return rc;
3950}
3951#endif /* CONFIG_NETLABEL */
3952
3953/**
3954 * __security_read_policy - read the policy.
3955 * @policy: SELinux policy
3956 * @data: binary policy data
3957 * @len: length of data in bytes
3958 *
3959 */
3960static int __security_read_policy(struct selinux_policy *policy,
3961 void *data, size_t *len)
3962{
3963 int rc;
3964 struct policy_file fp;
3965
3966 fp.data = data;
3967 fp.len = *len;
3968
3969 rc = policydb_write(&policy->policydb, &fp);
3970 if (rc)
3971 return rc;
3972
3973 *len = (unsigned long)fp.data - (unsigned long)data;
3974 return 0;
3975}
3976
3977/**
3978 * security_read_policy - read the policy.
3979 * @data: binary policy data
3980 * @len: length of data in bytes
3981 *
3982 */
3983int security_read_policy(void **data, size_t *len)
3984{
3985 struct selinux_state *state = &selinux_state;
3986 struct selinux_policy *policy;
3987
3988 policy = rcu_dereference_protected(
3989 state->policy, lockdep_is_held(&state->policy_mutex));
3990 if (!policy)
3991 return -EINVAL;
3992
3993 *len = policy->policydb.len;
3994 *data = vmalloc_user(*len);
3995 if (!*data)
3996 return -ENOMEM;
3997
3998 return __security_read_policy(policy, *data, len);
3999}
4000
4001/**
4002 * security_read_state_kernel - read the policy.
4003 * @data: binary policy data
4004 * @len: length of data in bytes
4005 *
4006 * Allocates kernel memory for reading SELinux policy.
4007 * This function is for internal use only and should not
4008 * be used for returning data to user space.
4009 *
4010 * This function must be called with policy_mutex held.
4011 */
4012int security_read_state_kernel(void **data, size_t *len)
4013{
4014 int err;
4015 struct selinux_state *state = &selinux_state;
4016 struct selinux_policy *policy;
4017
4018 policy = rcu_dereference_protected(
4019 state->policy, lockdep_is_held(&state->policy_mutex));
4020 if (!policy)
4021 return -EINVAL;
4022
4023 *len = policy->policydb.len;
4024 *data = vmalloc(*len);
4025 if (!*data)
4026 return -ENOMEM;
4027
4028 err = __security_read_policy(policy, *data, len);
4029 if (err) {
4030 vfree(*data);
4031 *data = NULL;
4032 *len = 0;
4033 }
4034 return err;
4035}
1/*
2 * Implementation of the security services.
3 *
4 * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
5 * James Morris <jmorris@redhat.com>
6 *
7 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
8 *
9 * Support for enhanced MLS infrastructure.
10 * Support for context based audit filters.
11 *
12 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
13 *
14 * Added conditional policy language extensions
15 *
16 * Updated: Hewlett-Packard <paul@paul-moore.com>
17 *
18 * Added support for NetLabel
19 * Added support for the policy capability bitmap
20 *
21 * Updated: Chad Sellers <csellers@tresys.com>
22 *
23 * Added validation of kernel classes and permissions
24 *
25 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
26 *
27 * Added support for bounds domain and audit messaged on masked permissions
28 *
29 * Updated: Guido Trentalancia <guido@trentalancia.com>
30 *
31 * Added support for runtime switching of the policy type
32 *
33 * Copyright (C) 2008, 2009 NEC Corporation
34 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
35 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
36 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
37 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
38 * This program is free software; you can redistribute it and/or modify
39 * it under the terms of the GNU General Public License as published by
40 * the Free Software Foundation, version 2.
41 */
42#include <linux/kernel.h>
43#include <linux/slab.h>
44#include <linux/string.h>
45#include <linux/spinlock.h>
46#include <linux/rcupdate.h>
47#include <linux/errno.h>
48#include <linux/in.h>
49#include <linux/sched.h>
50#include <linux/audit.h>
51#include <linux/mutex.h>
52#include <linux/selinux.h>
53#include <linux/flex_array.h>
54#include <linux/vmalloc.h>
55#include <net/netlabel.h>
56
57#include "flask.h"
58#include "avc.h"
59#include "avc_ss.h"
60#include "security.h"
61#include "context.h"
62#include "policydb.h"
63#include "sidtab.h"
64#include "services.h"
65#include "conditional.h"
66#include "mls.h"
67#include "objsec.h"
68#include "netlabel.h"
69#include "xfrm.h"
70#include "ebitmap.h"
71#include "audit.h"
72
73extern void selnl_notify_policyload(u32 seqno);
74
75int selinux_policycap_netpeer;
76int selinux_policycap_openperm;
77
78static DEFINE_RWLOCK(policy_rwlock);
79
80static struct sidtab sidtab;
81struct policydb policydb;
82int ss_initialized;
83
84/*
85 * The largest sequence number that has been used when
86 * providing an access decision to the access vector cache.
87 * The sequence number only changes when a policy change
88 * occurs.
89 */
90static u32 latest_granting;
91
92/* Forward declaration. */
93static int context_struct_to_string(struct context *context, char **scontext,
94 u32 *scontext_len);
95
96static void context_struct_compute_av(struct context *scontext,
97 struct context *tcontext,
98 u16 tclass,
99 struct av_decision *avd);
100
101struct selinux_mapping {
102 u16 value; /* policy value */
103 unsigned num_perms;
104 u32 perms[sizeof(u32) * 8];
105};
106
107static struct selinux_mapping *current_mapping;
108static u16 current_mapping_size;
109
110static int selinux_set_mapping(struct policydb *pol,
111 struct security_class_mapping *map,
112 struct selinux_mapping **out_map_p,
113 u16 *out_map_size)
114{
115 struct selinux_mapping *out_map = NULL;
116 size_t size = sizeof(struct selinux_mapping);
117 u16 i, j;
118 unsigned k;
119 bool print_unknown_handle = false;
120
121 /* Find number of classes in the input mapping */
122 if (!map)
123 return -EINVAL;
124 i = 0;
125 while (map[i].name)
126 i++;
127
128 /* Allocate space for the class records, plus one for class zero */
129 out_map = kcalloc(++i, size, GFP_ATOMIC);
130 if (!out_map)
131 return -ENOMEM;
132
133 /* Store the raw class and permission values */
134 j = 0;
135 while (map[j].name) {
136 struct security_class_mapping *p_in = map + (j++);
137 struct selinux_mapping *p_out = out_map + j;
138
139 /* An empty class string skips ahead */
140 if (!strcmp(p_in->name, "")) {
141 p_out->num_perms = 0;
142 continue;
143 }
144
145 p_out->value = string_to_security_class(pol, p_in->name);
146 if (!p_out->value) {
147 printk(KERN_INFO
148 "SELinux: Class %s not defined in policy.\n",
149 p_in->name);
150 if (pol->reject_unknown)
151 goto err;
152 p_out->num_perms = 0;
153 print_unknown_handle = true;
154 continue;
155 }
156
157 k = 0;
158 while (p_in->perms && p_in->perms[k]) {
159 /* An empty permission string skips ahead */
160 if (!*p_in->perms[k]) {
161 k++;
162 continue;
163 }
164 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
165 p_in->perms[k]);
166 if (!p_out->perms[k]) {
167 printk(KERN_INFO
168 "SELinux: Permission %s in class %s not defined in policy.\n",
169 p_in->perms[k], p_in->name);
170 if (pol->reject_unknown)
171 goto err;
172 print_unknown_handle = true;
173 }
174
175 k++;
176 }
177 p_out->num_perms = k;
178 }
179
180 if (print_unknown_handle)
181 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
182 pol->allow_unknown ? "allowed" : "denied");
183
184 *out_map_p = out_map;
185 *out_map_size = i;
186 return 0;
187err:
188 kfree(out_map);
189 return -EINVAL;
190}
191
192/*
193 * Get real, policy values from mapped values
194 */
195
196static u16 unmap_class(u16 tclass)
197{
198 if (tclass < current_mapping_size)
199 return current_mapping[tclass].value;
200
201 return tclass;
202}
203
204/*
205 * Get kernel value for class from its policy value
206 */
207static u16 map_class(u16 pol_value)
208{
209 u16 i;
210
211 for (i = 1; i < current_mapping_size; i++) {
212 if (current_mapping[i].value == pol_value)
213 return i;
214 }
215
216 return SECCLASS_NULL;
217}
218
219static void map_decision(u16 tclass, struct av_decision *avd,
220 int allow_unknown)
221{
222 if (tclass < current_mapping_size) {
223 unsigned i, n = current_mapping[tclass].num_perms;
224 u32 result;
225
226 for (i = 0, result = 0; i < n; i++) {
227 if (avd->allowed & current_mapping[tclass].perms[i])
228 result |= 1<<i;
229 if (allow_unknown && !current_mapping[tclass].perms[i])
230 result |= 1<<i;
231 }
232 avd->allowed = result;
233
234 for (i = 0, result = 0; i < n; i++)
235 if (avd->auditallow & current_mapping[tclass].perms[i])
236 result |= 1<<i;
237 avd->auditallow = result;
238
239 for (i = 0, result = 0; i < n; i++) {
240 if (avd->auditdeny & current_mapping[tclass].perms[i])
241 result |= 1<<i;
242 if (!allow_unknown && !current_mapping[tclass].perms[i])
243 result |= 1<<i;
244 }
245 /*
246 * In case the kernel has a bug and requests a permission
247 * between num_perms and the maximum permission number, we
248 * should audit that denial
249 */
250 for (; i < (sizeof(u32)*8); i++)
251 result |= 1<<i;
252 avd->auditdeny = result;
253 }
254}
255
256int security_mls_enabled(void)
257{
258 return policydb.mls_enabled;
259}
260
261/*
262 * Return the boolean value of a constraint expression
263 * when it is applied to the specified source and target
264 * security contexts.
265 *
266 * xcontext is a special beast... It is used by the validatetrans rules
267 * only. For these rules, scontext is the context before the transition,
268 * tcontext is the context after the transition, and xcontext is the context
269 * of the process performing the transition. All other callers of
270 * constraint_expr_eval should pass in NULL for xcontext.
271 */
272static int constraint_expr_eval(struct context *scontext,
273 struct context *tcontext,
274 struct context *xcontext,
275 struct constraint_expr *cexpr)
276{
277 u32 val1, val2;
278 struct context *c;
279 struct role_datum *r1, *r2;
280 struct mls_level *l1, *l2;
281 struct constraint_expr *e;
282 int s[CEXPR_MAXDEPTH];
283 int sp = -1;
284
285 for (e = cexpr; e; e = e->next) {
286 switch (e->expr_type) {
287 case CEXPR_NOT:
288 BUG_ON(sp < 0);
289 s[sp] = !s[sp];
290 break;
291 case CEXPR_AND:
292 BUG_ON(sp < 1);
293 sp--;
294 s[sp] &= s[sp + 1];
295 break;
296 case CEXPR_OR:
297 BUG_ON(sp < 1);
298 sp--;
299 s[sp] |= s[sp + 1];
300 break;
301 case CEXPR_ATTR:
302 if (sp == (CEXPR_MAXDEPTH - 1))
303 return 0;
304 switch (e->attr) {
305 case CEXPR_USER:
306 val1 = scontext->user;
307 val2 = tcontext->user;
308 break;
309 case CEXPR_TYPE:
310 val1 = scontext->type;
311 val2 = tcontext->type;
312 break;
313 case CEXPR_ROLE:
314 val1 = scontext->role;
315 val2 = tcontext->role;
316 r1 = policydb.role_val_to_struct[val1 - 1];
317 r2 = policydb.role_val_to_struct[val2 - 1];
318 switch (e->op) {
319 case CEXPR_DOM:
320 s[++sp] = ebitmap_get_bit(&r1->dominates,
321 val2 - 1);
322 continue;
323 case CEXPR_DOMBY:
324 s[++sp] = ebitmap_get_bit(&r2->dominates,
325 val1 - 1);
326 continue;
327 case CEXPR_INCOMP:
328 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
329 val2 - 1) &&
330 !ebitmap_get_bit(&r2->dominates,
331 val1 - 1));
332 continue;
333 default:
334 break;
335 }
336 break;
337 case CEXPR_L1L2:
338 l1 = &(scontext->range.level[0]);
339 l2 = &(tcontext->range.level[0]);
340 goto mls_ops;
341 case CEXPR_L1H2:
342 l1 = &(scontext->range.level[0]);
343 l2 = &(tcontext->range.level[1]);
344 goto mls_ops;
345 case CEXPR_H1L2:
346 l1 = &(scontext->range.level[1]);
347 l2 = &(tcontext->range.level[0]);
348 goto mls_ops;
349 case CEXPR_H1H2:
350 l1 = &(scontext->range.level[1]);
351 l2 = &(tcontext->range.level[1]);
352 goto mls_ops;
353 case CEXPR_L1H1:
354 l1 = &(scontext->range.level[0]);
355 l2 = &(scontext->range.level[1]);
356 goto mls_ops;
357 case CEXPR_L2H2:
358 l1 = &(tcontext->range.level[0]);
359 l2 = &(tcontext->range.level[1]);
360 goto mls_ops;
361mls_ops:
362 switch (e->op) {
363 case CEXPR_EQ:
364 s[++sp] = mls_level_eq(l1, l2);
365 continue;
366 case CEXPR_NEQ:
367 s[++sp] = !mls_level_eq(l1, l2);
368 continue;
369 case CEXPR_DOM:
370 s[++sp] = mls_level_dom(l1, l2);
371 continue;
372 case CEXPR_DOMBY:
373 s[++sp] = mls_level_dom(l2, l1);
374 continue;
375 case CEXPR_INCOMP:
376 s[++sp] = mls_level_incomp(l2, l1);
377 continue;
378 default:
379 BUG();
380 return 0;
381 }
382 break;
383 default:
384 BUG();
385 return 0;
386 }
387
388 switch (e->op) {
389 case CEXPR_EQ:
390 s[++sp] = (val1 == val2);
391 break;
392 case CEXPR_NEQ:
393 s[++sp] = (val1 != val2);
394 break;
395 default:
396 BUG();
397 return 0;
398 }
399 break;
400 case CEXPR_NAMES:
401 if (sp == (CEXPR_MAXDEPTH-1))
402 return 0;
403 c = scontext;
404 if (e->attr & CEXPR_TARGET)
405 c = tcontext;
406 else if (e->attr & CEXPR_XTARGET) {
407 c = xcontext;
408 if (!c) {
409 BUG();
410 return 0;
411 }
412 }
413 if (e->attr & CEXPR_USER)
414 val1 = c->user;
415 else if (e->attr & CEXPR_ROLE)
416 val1 = c->role;
417 else if (e->attr & CEXPR_TYPE)
418 val1 = c->type;
419 else {
420 BUG();
421 return 0;
422 }
423
424 switch (e->op) {
425 case CEXPR_EQ:
426 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
427 break;
428 case CEXPR_NEQ:
429 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
430 break;
431 default:
432 BUG();
433 return 0;
434 }
435 break;
436 default:
437 BUG();
438 return 0;
439 }
440 }
441
442 BUG_ON(sp != 0);
443 return s[0];
444}
445
446/*
447 * security_dump_masked_av - dumps masked permissions during
448 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
449 */
450static int dump_masked_av_helper(void *k, void *d, void *args)
451{
452 struct perm_datum *pdatum = d;
453 char **permission_names = args;
454
455 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
456
457 permission_names[pdatum->value - 1] = (char *)k;
458
459 return 0;
460}
461
462static void security_dump_masked_av(struct context *scontext,
463 struct context *tcontext,
464 u16 tclass,
465 u32 permissions,
466 const char *reason)
467{
468 struct common_datum *common_dat;
469 struct class_datum *tclass_dat;
470 struct audit_buffer *ab;
471 char *tclass_name;
472 char *scontext_name = NULL;
473 char *tcontext_name = NULL;
474 char *permission_names[32];
475 int index;
476 u32 length;
477 bool need_comma = false;
478
479 if (!permissions)
480 return;
481
482 tclass_name = sym_name(&policydb, SYM_CLASSES, tclass - 1);
483 tclass_dat = policydb.class_val_to_struct[tclass - 1];
484 common_dat = tclass_dat->comdatum;
485
486 /* init permission_names */
487 if (common_dat &&
488 hashtab_map(common_dat->permissions.table,
489 dump_masked_av_helper, permission_names) < 0)
490 goto out;
491
492 if (hashtab_map(tclass_dat->permissions.table,
493 dump_masked_av_helper, permission_names) < 0)
494 goto out;
495
496 /* get scontext/tcontext in text form */
497 if (context_struct_to_string(scontext,
498 &scontext_name, &length) < 0)
499 goto out;
500
501 if (context_struct_to_string(tcontext,
502 &tcontext_name, &length) < 0)
503 goto out;
504
505 /* audit a message */
506 ab = audit_log_start(current->audit_context,
507 GFP_ATOMIC, AUDIT_SELINUX_ERR);
508 if (!ab)
509 goto out;
510
511 audit_log_format(ab, "op=security_compute_av reason=%s "
512 "scontext=%s tcontext=%s tclass=%s perms=",
513 reason, scontext_name, tcontext_name, tclass_name);
514
515 for (index = 0; index < 32; index++) {
516 u32 mask = (1 << index);
517
518 if ((mask & permissions) == 0)
519 continue;
520
521 audit_log_format(ab, "%s%s",
522 need_comma ? "," : "",
523 permission_names[index]
524 ? permission_names[index] : "????");
525 need_comma = true;
526 }
527 audit_log_end(ab);
528out:
529 /* release scontext/tcontext */
530 kfree(tcontext_name);
531 kfree(scontext_name);
532
533 return;
534}
535
536/*
537 * security_boundary_permission - drops violated permissions
538 * on boundary constraint.
539 */
540static void type_attribute_bounds_av(struct context *scontext,
541 struct context *tcontext,
542 u16 tclass,
543 struct av_decision *avd)
544{
545 struct context lo_scontext;
546 struct context lo_tcontext;
547 struct av_decision lo_avd;
548 struct type_datum *source;
549 struct type_datum *target;
550 u32 masked = 0;
551
552 source = flex_array_get_ptr(policydb.type_val_to_struct_array,
553 scontext->type - 1);
554 BUG_ON(!source);
555
556 target = flex_array_get_ptr(policydb.type_val_to_struct_array,
557 tcontext->type - 1);
558 BUG_ON(!target);
559
560 if (source->bounds) {
561 memset(&lo_avd, 0, sizeof(lo_avd));
562
563 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
564 lo_scontext.type = source->bounds;
565
566 context_struct_compute_av(&lo_scontext,
567 tcontext,
568 tclass,
569 &lo_avd);
570 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
571 return; /* no masked permission */
572 masked = ~lo_avd.allowed & avd->allowed;
573 }
574
575 if (target->bounds) {
576 memset(&lo_avd, 0, sizeof(lo_avd));
577
578 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
579 lo_tcontext.type = target->bounds;
580
581 context_struct_compute_av(scontext,
582 &lo_tcontext,
583 tclass,
584 &lo_avd);
585 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
586 return; /* no masked permission */
587 masked = ~lo_avd.allowed & avd->allowed;
588 }
589
590 if (source->bounds && target->bounds) {
591 memset(&lo_avd, 0, sizeof(lo_avd));
592 /*
593 * lo_scontext and lo_tcontext are already
594 * set up.
595 */
596
597 context_struct_compute_av(&lo_scontext,
598 &lo_tcontext,
599 tclass,
600 &lo_avd);
601 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
602 return; /* no masked permission */
603 masked = ~lo_avd.allowed & avd->allowed;
604 }
605
606 if (masked) {
607 /* mask violated permissions */
608 avd->allowed &= ~masked;
609
610 /* audit masked permissions */
611 security_dump_masked_av(scontext, tcontext,
612 tclass, masked, "bounds");
613 }
614}
615
616/*
617 * Compute access vectors based on a context structure pair for
618 * the permissions in a particular class.
619 */
620static void context_struct_compute_av(struct context *scontext,
621 struct context *tcontext,
622 u16 tclass,
623 struct av_decision *avd)
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
638 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
639 if (printk_ratelimit())
640 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass);
641 return;
642 }
643
644 tclass_datum = policydb.class_val_to_struct[tclass - 1];
645
646 /*
647 * If a specific type enforcement rule was defined for
648 * this permission check, then use it.
649 */
650 avkey.target_class = tclass;
651 avkey.specified = AVTAB_AV;
652 sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1);
653 BUG_ON(!sattr);
654 tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1);
655 BUG_ON(!tattr);
656 ebitmap_for_each_positive_bit(sattr, snode, i) {
657 ebitmap_for_each_positive_bit(tattr, tnode, j) {
658 avkey.source_type = i + 1;
659 avkey.target_type = j + 1;
660 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
661 node;
662 node = avtab_search_node_next(node, avkey.specified)) {
663 if (node->key.specified == AVTAB_ALLOWED)
664 avd->allowed |= node->datum.data;
665 else if (node->key.specified == AVTAB_AUDITALLOW)
666 avd->auditallow |= node->datum.data;
667 else if (node->key.specified == AVTAB_AUDITDENY)
668 avd->auditdeny &= node->datum.data;
669 }
670
671 /* Check conditional av table for additional permissions */
672 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
673
674 }
675 }
676
677 /*
678 * Remove any permissions prohibited by a constraint (this includes
679 * the MLS policy).
680 */
681 constraint = tclass_datum->constraints;
682 while (constraint) {
683 if ((constraint->permissions & (avd->allowed)) &&
684 !constraint_expr_eval(scontext, tcontext, NULL,
685 constraint->expr)) {
686 avd->allowed &= ~(constraint->permissions);
687 }
688 constraint = constraint->next;
689 }
690
691 /*
692 * If checking process transition permission and the
693 * role is changing, then check the (current_role, new_role)
694 * pair.
695 */
696 if (tclass == policydb.process_class &&
697 (avd->allowed & policydb.process_trans_perms) &&
698 scontext->role != tcontext->role) {
699 for (ra = policydb.role_allow; ra; ra = ra->next) {
700 if (scontext->role == ra->role &&
701 tcontext->role == ra->new_role)
702 break;
703 }
704 if (!ra)
705 avd->allowed &= ~policydb.process_trans_perms;
706 }
707
708 /*
709 * If the given source and target types have boundary
710 * constraint, lazy checks have to mask any violated
711 * permission and notice it to userspace via audit.
712 */
713 type_attribute_bounds_av(scontext, tcontext,
714 tclass, avd);
715}
716
717static int security_validtrans_handle_fail(struct context *ocontext,
718 struct context *ncontext,
719 struct context *tcontext,
720 u16 tclass)
721{
722 char *o = NULL, *n = NULL, *t = NULL;
723 u32 olen, nlen, tlen;
724
725 if (context_struct_to_string(ocontext, &o, &olen))
726 goto out;
727 if (context_struct_to_string(ncontext, &n, &nlen))
728 goto out;
729 if (context_struct_to_string(tcontext, &t, &tlen))
730 goto out;
731 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
732 "security_validate_transition: denied for"
733 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
734 o, n, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
735out:
736 kfree(o);
737 kfree(n);
738 kfree(t);
739
740 if (!selinux_enforcing)
741 return 0;
742 return -EPERM;
743}
744
745int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
746 u16 orig_tclass)
747{
748 struct context *ocontext;
749 struct context *ncontext;
750 struct context *tcontext;
751 struct class_datum *tclass_datum;
752 struct constraint_node *constraint;
753 u16 tclass;
754 int rc = 0;
755
756 if (!ss_initialized)
757 return 0;
758
759 read_lock(&policy_rwlock);
760
761 tclass = unmap_class(orig_tclass);
762
763 if (!tclass || tclass > policydb.p_classes.nprim) {
764 printk(KERN_ERR "SELinux: %s: unrecognized class %d\n",
765 __func__, tclass);
766 rc = -EINVAL;
767 goto out;
768 }
769 tclass_datum = policydb.class_val_to_struct[tclass - 1];
770
771 ocontext = sidtab_search(&sidtab, oldsid);
772 if (!ocontext) {
773 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
774 __func__, oldsid);
775 rc = -EINVAL;
776 goto out;
777 }
778
779 ncontext = sidtab_search(&sidtab, newsid);
780 if (!ncontext) {
781 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
782 __func__, newsid);
783 rc = -EINVAL;
784 goto out;
785 }
786
787 tcontext = sidtab_search(&sidtab, tasksid);
788 if (!tcontext) {
789 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
790 __func__, tasksid);
791 rc = -EINVAL;
792 goto out;
793 }
794
795 constraint = tclass_datum->validatetrans;
796 while (constraint) {
797 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
798 constraint->expr)) {
799 rc = security_validtrans_handle_fail(ocontext, ncontext,
800 tcontext, tclass);
801 goto out;
802 }
803 constraint = constraint->next;
804 }
805
806out:
807 read_unlock(&policy_rwlock);
808 return rc;
809}
810
811/*
812 * security_bounded_transition - check whether the given
813 * transition is directed to bounded, or not.
814 * It returns 0, if @newsid is bounded by @oldsid.
815 * Otherwise, it returns error code.
816 *
817 * @oldsid : current security identifier
818 * @newsid : destinated security identifier
819 */
820int security_bounded_transition(u32 old_sid, u32 new_sid)
821{
822 struct context *old_context, *new_context;
823 struct type_datum *type;
824 int index;
825 int rc;
826
827 read_lock(&policy_rwlock);
828
829 rc = -EINVAL;
830 old_context = sidtab_search(&sidtab, old_sid);
831 if (!old_context) {
832 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
833 __func__, old_sid);
834 goto out;
835 }
836
837 rc = -EINVAL;
838 new_context = sidtab_search(&sidtab, new_sid);
839 if (!new_context) {
840 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
841 __func__, new_sid);
842 goto out;
843 }
844
845 rc = 0;
846 /* type/domain unchanged */
847 if (old_context->type == new_context->type)
848 goto out;
849
850 index = new_context->type;
851 while (true) {
852 type = flex_array_get_ptr(policydb.type_val_to_struct_array,
853 index - 1);
854 BUG_ON(!type);
855
856 /* not bounded anymore */
857 rc = -EPERM;
858 if (!type->bounds)
859 break;
860
861 /* @newsid is bounded by @oldsid */
862 rc = 0;
863 if (type->bounds == old_context->type)
864 break;
865
866 index = type->bounds;
867 }
868
869 if (rc) {
870 char *old_name = NULL;
871 char *new_name = NULL;
872 u32 length;
873
874 if (!context_struct_to_string(old_context,
875 &old_name, &length) &&
876 !context_struct_to_string(new_context,
877 &new_name, &length)) {
878 audit_log(current->audit_context,
879 GFP_ATOMIC, AUDIT_SELINUX_ERR,
880 "op=security_bounded_transition "
881 "result=denied "
882 "oldcontext=%s newcontext=%s",
883 old_name, new_name);
884 }
885 kfree(new_name);
886 kfree(old_name);
887 }
888out:
889 read_unlock(&policy_rwlock);
890
891 return rc;
892}
893
894static void avd_init(struct av_decision *avd)
895{
896 avd->allowed = 0;
897 avd->auditallow = 0;
898 avd->auditdeny = 0xffffffff;
899 avd->seqno = latest_granting;
900 avd->flags = 0;
901}
902
903
904/**
905 * security_compute_av - Compute access vector decisions.
906 * @ssid: source security identifier
907 * @tsid: target security identifier
908 * @tclass: target security class
909 * @avd: access vector decisions
910 *
911 * Compute a set of access vector decisions based on the
912 * SID pair (@ssid, @tsid) for the permissions in @tclass.
913 */
914void security_compute_av(u32 ssid,
915 u32 tsid,
916 u16 orig_tclass,
917 struct av_decision *avd)
918{
919 u16 tclass;
920 struct context *scontext = NULL, *tcontext = NULL;
921
922 read_lock(&policy_rwlock);
923 avd_init(avd);
924 if (!ss_initialized)
925 goto allow;
926
927 scontext = sidtab_search(&sidtab, ssid);
928 if (!scontext) {
929 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
930 __func__, ssid);
931 goto out;
932 }
933
934 /* permissive domain? */
935 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
936 avd->flags |= AVD_FLAGS_PERMISSIVE;
937
938 tcontext = sidtab_search(&sidtab, tsid);
939 if (!tcontext) {
940 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
941 __func__, tsid);
942 goto out;
943 }
944
945 tclass = unmap_class(orig_tclass);
946 if (unlikely(orig_tclass && !tclass)) {
947 if (policydb.allow_unknown)
948 goto allow;
949 goto out;
950 }
951 context_struct_compute_av(scontext, tcontext, tclass, avd);
952 map_decision(orig_tclass, avd, policydb.allow_unknown);
953out:
954 read_unlock(&policy_rwlock);
955 return;
956allow:
957 avd->allowed = 0xffffffff;
958 goto out;
959}
960
961void security_compute_av_user(u32 ssid,
962 u32 tsid,
963 u16 tclass,
964 struct av_decision *avd)
965{
966 struct context *scontext = NULL, *tcontext = NULL;
967
968 read_lock(&policy_rwlock);
969 avd_init(avd);
970 if (!ss_initialized)
971 goto allow;
972
973 scontext = sidtab_search(&sidtab, ssid);
974 if (!scontext) {
975 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
976 __func__, ssid);
977 goto out;
978 }
979
980 /* permissive domain? */
981 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
982 avd->flags |= AVD_FLAGS_PERMISSIVE;
983
984 tcontext = sidtab_search(&sidtab, tsid);
985 if (!tcontext) {
986 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
987 __func__, tsid);
988 goto out;
989 }
990
991 if (unlikely(!tclass)) {
992 if (policydb.allow_unknown)
993 goto allow;
994 goto out;
995 }
996
997 context_struct_compute_av(scontext, tcontext, tclass, avd);
998 out:
999 read_unlock(&policy_rwlock);
1000 return;
1001allow:
1002 avd->allowed = 0xffffffff;
1003 goto out;
1004}
1005
1006/*
1007 * Write the security context string representation of
1008 * the context structure `context' into a dynamically
1009 * allocated string of the correct size. Set `*scontext'
1010 * to point to this string and set `*scontext_len' to
1011 * the length of the string.
1012 */
1013static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
1014{
1015 char *scontextp;
1016
1017 if (scontext)
1018 *scontext = NULL;
1019 *scontext_len = 0;
1020
1021 if (context->len) {
1022 *scontext_len = context->len;
1023 *scontext = kstrdup(context->str, GFP_ATOMIC);
1024 if (!(*scontext))
1025 return -ENOMEM;
1026 return 0;
1027 }
1028
1029 /* Compute the size of the context. */
1030 *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1;
1031 *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1;
1032 *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1;
1033 *scontext_len += mls_compute_context_len(context);
1034
1035 if (!scontext)
1036 return 0;
1037
1038 /* Allocate space for the context; caller must free this space. */
1039 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1040 if (!scontextp)
1041 return -ENOMEM;
1042 *scontext = scontextp;
1043
1044 /*
1045 * Copy the user name, role name and type name into the context.
1046 */
1047 sprintf(scontextp, "%s:%s:%s",
1048 sym_name(&policydb, SYM_USERS, context->user - 1),
1049 sym_name(&policydb, SYM_ROLES, context->role - 1),
1050 sym_name(&policydb, SYM_TYPES, context->type - 1));
1051 scontextp += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) +
1052 1 + strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) +
1053 1 + strlen(sym_name(&policydb, SYM_TYPES, context->type - 1));
1054
1055 mls_sid_to_context(context, &scontextp);
1056
1057 *scontextp = 0;
1058
1059 return 0;
1060}
1061
1062#include "initial_sid_to_string.h"
1063
1064const char *security_get_initial_sid_context(u32 sid)
1065{
1066 if (unlikely(sid > SECINITSID_NUM))
1067 return NULL;
1068 return initial_sid_to_string[sid];
1069}
1070
1071static int security_sid_to_context_core(u32 sid, char **scontext,
1072 u32 *scontext_len, int force)
1073{
1074 struct context *context;
1075 int rc = 0;
1076
1077 if (scontext)
1078 *scontext = NULL;
1079 *scontext_len = 0;
1080
1081 if (!ss_initialized) {
1082 if (sid <= SECINITSID_NUM) {
1083 char *scontextp;
1084
1085 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1086 if (!scontext)
1087 goto out;
1088 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1089 if (!scontextp) {
1090 rc = -ENOMEM;
1091 goto out;
1092 }
1093 strcpy(scontextp, initial_sid_to_string[sid]);
1094 *scontext = scontextp;
1095 goto out;
1096 }
1097 printk(KERN_ERR "SELinux: %s: called before initial "
1098 "load_policy on unknown SID %d\n", __func__, sid);
1099 rc = -EINVAL;
1100 goto out;
1101 }
1102 read_lock(&policy_rwlock);
1103 if (force)
1104 context = sidtab_search_force(&sidtab, sid);
1105 else
1106 context = sidtab_search(&sidtab, sid);
1107 if (!context) {
1108 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1109 __func__, sid);
1110 rc = -EINVAL;
1111 goto out_unlock;
1112 }
1113 rc = context_struct_to_string(context, scontext, scontext_len);
1114out_unlock:
1115 read_unlock(&policy_rwlock);
1116out:
1117 return rc;
1118
1119}
1120
1121/**
1122 * security_sid_to_context - Obtain a context for a given SID.
1123 * @sid: security identifier, SID
1124 * @scontext: security context
1125 * @scontext_len: length in bytes
1126 *
1127 * Write the string representation of the context associated with @sid
1128 * into a dynamically allocated string of the correct size. Set @scontext
1129 * to point to this string and set @scontext_len to the length of the string.
1130 */
1131int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1132{
1133 return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1134}
1135
1136int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1137{
1138 return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1139}
1140
1141/*
1142 * Caveat: Mutates scontext.
1143 */
1144static int string_to_context_struct(struct policydb *pol,
1145 struct sidtab *sidtabp,
1146 char *scontext,
1147 u32 scontext_len,
1148 struct context *ctx,
1149 u32 def_sid)
1150{
1151 struct role_datum *role;
1152 struct type_datum *typdatum;
1153 struct user_datum *usrdatum;
1154 char *scontextp, *p, oldc;
1155 int rc = 0;
1156
1157 context_init(ctx);
1158
1159 /* Parse the security context. */
1160
1161 rc = -EINVAL;
1162 scontextp = (char *) scontext;
1163
1164 /* Extract the user. */
1165 p = scontextp;
1166 while (*p && *p != ':')
1167 p++;
1168
1169 if (*p == 0)
1170 goto out;
1171
1172 *p++ = 0;
1173
1174 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1175 if (!usrdatum)
1176 goto out;
1177
1178 ctx->user = usrdatum->value;
1179
1180 /* Extract role. */
1181 scontextp = p;
1182 while (*p && *p != ':')
1183 p++;
1184
1185 if (*p == 0)
1186 goto out;
1187
1188 *p++ = 0;
1189
1190 role = hashtab_search(pol->p_roles.table, scontextp);
1191 if (!role)
1192 goto out;
1193 ctx->role = role->value;
1194
1195 /* Extract type. */
1196 scontextp = p;
1197 while (*p && *p != ':')
1198 p++;
1199 oldc = *p;
1200 *p++ = 0;
1201
1202 typdatum = hashtab_search(pol->p_types.table, scontextp);
1203 if (!typdatum || typdatum->attribute)
1204 goto out;
1205
1206 ctx->type = typdatum->value;
1207
1208 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1209 if (rc)
1210 goto out;
1211
1212 rc = -EINVAL;
1213 if ((p - scontext) < scontext_len)
1214 goto out;
1215
1216 /* Check the validity of the new context. */
1217 if (!policydb_context_isvalid(pol, ctx))
1218 goto out;
1219 rc = 0;
1220out:
1221 if (rc)
1222 context_destroy(ctx);
1223 return rc;
1224}
1225
1226static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1227 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1228 int force)
1229{
1230 char *scontext2, *str = NULL;
1231 struct context context;
1232 int rc = 0;
1233
1234 if (!ss_initialized) {
1235 int i;
1236
1237 for (i = 1; i < SECINITSID_NUM; i++) {
1238 if (!strcmp(initial_sid_to_string[i], scontext)) {
1239 *sid = i;
1240 return 0;
1241 }
1242 }
1243 *sid = SECINITSID_KERNEL;
1244 return 0;
1245 }
1246 *sid = SECSID_NULL;
1247
1248 /* Copy the string so that we can modify the copy as we parse it. */
1249 scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1250 if (!scontext2)
1251 return -ENOMEM;
1252 memcpy(scontext2, scontext, scontext_len);
1253 scontext2[scontext_len] = 0;
1254
1255 if (force) {
1256 /* Save another copy for storing in uninterpreted form */
1257 rc = -ENOMEM;
1258 str = kstrdup(scontext2, gfp_flags);
1259 if (!str)
1260 goto out;
1261 }
1262
1263 read_lock(&policy_rwlock);
1264 rc = string_to_context_struct(&policydb, &sidtab, scontext2,
1265 scontext_len, &context, def_sid);
1266 if (rc == -EINVAL && force) {
1267 context.str = str;
1268 context.len = scontext_len;
1269 str = NULL;
1270 } else if (rc)
1271 goto out_unlock;
1272 rc = sidtab_context_to_sid(&sidtab, &context, sid);
1273 context_destroy(&context);
1274out_unlock:
1275 read_unlock(&policy_rwlock);
1276out:
1277 kfree(scontext2);
1278 kfree(str);
1279 return rc;
1280}
1281
1282/**
1283 * security_context_to_sid - Obtain a SID for a given security context.
1284 * @scontext: security context
1285 * @scontext_len: length in bytes
1286 * @sid: security identifier, SID
1287 *
1288 * Obtains a SID associated with the security context that
1289 * has the string representation specified by @scontext.
1290 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1291 * memory is available, or 0 on success.
1292 */
1293int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
1294{
1295 return security_context_to_sid_core(scontext, scontext_len,
1296 sid, SECSID_NULL, GFP_KERNEL, 0);
1297}
1298
1299/**
1300 * security_context_to_sid_default - Obtain a SID for a given security context,
1301 * falling back to specified default if needed.
1302 *
1303 * @scontext: security context
1304 * @scontext_len: length in bytes
1305 * @sid: security identifier, SID
1306 * @def_sid: default SID to assign on error
1307 *
1308 * Obtains a SID associated with the security context that
1309 * has the string representation specified by @scontext.
1310 * The default SID is passed to the MLS layer to be used to allow
1311 * kernel labeling of the MLS field if the MLS field is not present
1312 * (for upgrading to MLS without full relabel).
1313 * Implicitly forces adding of the context even if it cannot be mapped yet.
1314 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1315 * memory is available, or 0 on success.
1316 */
1317int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1318 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1319{
1320 return security_context_to_sid_core(scontext, scontext_len,
1321 sid, def_sid, gfp_flags, 1);
1322}
1323
1324int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1325 u32 *sid)
1326{
1327 return security_context_to_sid_core(scontext, scontext_len,
1328 sid, SECSID_NULL, GFP_KERNEL, 1);
1329}
1330
1331static int compute_sid_handle_invalid_context(
1332 struct context *scontext,
1333 struct context *tcontext,
1334 u16 tclass,
1335 struct context *newcontext)
1336{
1337 char *s = NULL, *t = NULL, *n = NULL;
1338 u32 slen, tlen, nlen;
1339
1340 if (context_struct_to_string(scontext, &s, &slen))
1341 goto out;
1342 if (context_struct_to_string(tcontext, &t, &tlen))
1343 goto out;
1344 if (context_struct_to_string(newcontext, &n, &nlen))
1345 goto out;
1346 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1347 "security_compute_sid: invalid context %s"
1348 " for scontext=%s"
1349 " tcontext=%s"
1350 " tclass=%s",
1351 n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
1352out:
1353 kfree(s);
1354 kfree(t);
1355 kfree(n);
1356 if (!selinux_enforcing)
1357 return 0;
1358 return -EACCES;
1359}
1360
1361static void filename_compute_type(struct policydb *p, struct context *newcontext,
1362 u32 stype, u32 ttype, u16 tclass,
1363 const char *objname)
1364{
1365 struct filename_trans ft;
1366 struct filename_trans_datum *otype;
1367
1368 /*
1369 * Most filename trans rules are going to live in specific directories
1370 * like /dev or /var/run. This bitmap will quickly skip rule searches
1371 * if the ttype does not contain any rules.
1372 */
1373 if (!ebitmap_get_bit(&p->filename_trans_ttypes, ttype))
1374 return;
1375
1376 ft.stype = stype;
1377 ft.ttype = ttype;
1378 ft.tclass = tclass;
1379 ft.name = objname;
1380
1381 otype = hashtab_search(p->filename_trans, &ft);
1382 if (otype)
1383 newcontext->type = otype->otype;
1384}
1385
1386static int security_compute_sid(u32 ssid,
1387 u32 tsid,
1388 u16 orig_tclass,
1389 u32 specified,
1390 const char *objname,
1391 u32 *out_sid,
1392 bool kern)
1393{
1394 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1395 struct role_trans *roletr = NULL;
1396 struct avtab_key avkey;
1397 struct avtab_datum *avdatum;
1398 struct avtab_node *node;
1399 u16 tclass;
1400 int rc = 0;
1401 bool sock;
1402
1403 if (!ss_initialized) {
1404 switch (orig_tclass) {
1405 case SECCLASS_PROCESS: /* kernel value */
1406 *out_sid = ssid;
1407 break;
1408 default:
1409 *out_sid = tsid;
1410 break;
1411 }
1412 goto out;
1413 }
1414
1415 context_init(&newcontext);
1416
1417 read_lock(&policy_rwlock);
1418
1419 if (kern) {
1420 tclass = unmap_class(orig_tclass);
1421 sock = security_is_socket_class(orig_tclass);
1422 } else {
1423 tclass = orig_tclass;
1424 sock = security_is_socket_class(map_class(tclass));
1425 }
1426
1427 scontext = sidtab_search(&sidtab, ssid);
1428 if (!scontext) {
1429 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1430 __func__, ssid);
1431 rc = -EINVAL;
1432 goto out_unlock;
1433 }
1434 tcontext = sidtab_search(&sidtab, tsid);
1435 if (!tcontext) {
1436 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1437 __func__, tsid);
1438 rc = -EINVAL;
1439 goto out_unlock;
1440 }
1441
1442 /* Set the user identity. */
1443 switch (specified) {
1444 case AVTAB_TRANSITION:
1445 case AVTAB_CHANGE:
1446 /* Use the process user identity. */
1447 newcontext.user = scontext->user;
1448 break;
1449 case AVTAB_MEMBER:
1450 /* Use the related object owner. */
1451 newcontext.user = tcontext->user;
1452 break;
1453 }
1454
1455 /* Set the role and type to default values. */
1456 if ((tclass == policydb.process_class) || (sock == true)) {
1457 /* Use the current role and type of process. */
1458 newcontext.role = scontext->role;
1459 newcontext.type = scontext->type;
1460 } else {
1461 /* Use the well-defined object role. */
1462 newcontext.role = OBJECT_R_VAL;
1463 /* Use the type of the related object. */
1464 newcontext.type = tcontext->type;
1465 }
1466
1467 /* Look for a type transition/member/change rule. */
1468 avkey.source_type = scontext->type;
1469 avkey.target_type = tcontext->type;
1470 avkey.target_class = tclass;
1471 avkey.specified = specified;
1472 avdatum = avtab_search(&policydb.te_avtab, &avkey);
1473
1474 /* If no permanent rule, also check for enabled conditional rules */
1475 if (!avdatum) {
1476 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1477 for (; node; node = avtab_search_node_next(node, specified)) {
1478 if (node->key.specified & AVTAB_ENABLED) {
1479 avdatum = &node->datum;
1480 break;
1481 }
1482 }
1483 }
1484
1485 if (avdatum) {
1486 /* Use the type from the type transition/member/change rule. */
1487 newcontext.type = avdatum->data;
1488 }
1489
1490 /* if we have a objname this is a file trans check so check those rules */
1491 if (objname)
1492 filename_compute_type(&policydb, &newcontext, scontext->type,
1493 tcontext->type, tclass, objname);
1494
1495 /* Check for class-specific changes. */
1496 if (specified & AVTAB_TRANSITION) {
1497 /* Look for a role transition rule. */
1498 for (roletr = policydb.role_tr; roletr; roletr = roletr->next) {
1499 if ((roletr->role == scontext->role) &&
1500 (roletr->type == tcontext->type) &&
1501 (roletr->tclass == tclass)) {
1502 /* Use the role transition rule. */
1503 newcontext.role = roletr->new_role;
1504 break;
1505 }
1506 }
1507 }
1508
1509 /* Set the MLS attributes.
1510 This is done last because it may allocate memory. */
1511 rc = mls_compute_sid(scontext, tcontext, tclass, specified,
1512 &newcontext, sock);
1513 if (rc)
1514 goto out_unlock;
1515
1516 /* Check the validity of the context. */
1517 if (!policydb_context_isvalid(&policydb, &newcontext)) {
1518 rc = compute_sid_handle_invalid_context(scontext,
1519 tcontext,
1520 tclass,
1521 &newcontext);
1522 if (rc)
1523 goto out_unlock;
1524 }
1525 /* Obtain the sid for the context. */
1526 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1527out_unlock:
1528 read_unlock(&policy_rwlock);
1529 context_destroy(&newcontext);
1530out:
1531 return rc;
1532}
1533
1534/**
1535 * security_transition_sid - Compute the SID for a new subject/object.
1536 * @ssid: source security identifier
1537 * @tsid: target security identifier
1538 * @tclass: target security class
1539 * @out_sid: security identifier for new subject/object
1540 *
1541 * Compute a SID to use for labeling a new subject or object in the
1542 * class @tclass based on a SID pair (@ssid, @tsid).
1543 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1544 * if insufficient memory is available, or %0 if the new SID was
1545 * computed successfully.
1546 */
1547int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1548 const struct qstr *qstr, u32 *out_sid)
1549{
1550 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1551 qstr ? qstr->name : NULL, out_sid, true);
1552}
1553
1554int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1555 const char *objname, u32 *out_sid)
1556{
1557 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1558 objname, out_sid, false);
1559}
1560
1561/**
1562 * security_member_sid - Compute the SID for member selection.
1563 * @ssid: source security identifier
1564 * @tsid: target security identifier
1565 * @tclass: target security class
1566 * @out_sid: security identifier for selected member
1567 *
1568 * Compute a SID to use when selecting a member of a polyinstantiated
1569 * object of class @tclass based on a SID pair (@ssid, @tsid).
1570 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1571 * if insufficient memory is available, or %0 if the SID was
1572 * computed successfully.
1573 */
1574int security_member_sid(u32 ssid,
1575 u32 tsid,
1576 u16 tclass,
1577 u32 *out_sid)
1578{
1579 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL,
1580 out_sid, false);
1581}
1582
1583/**
1584 * security_change_sid - Compute the SID for object relabeling.
1585 * @ssid: source security identifier
1586 * @tsid: target security identifier
1587 * @tclass: target security class
1588 * @out_sid: security identifier for selected member
1589 *
1590 * Compute a SID to use for relabeling an object of class @tclass
1591 * based on a SID pair (@ssid, @tsid).
1592 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1593 * if insufficient memory is available, or %0 if the SID was
1594 * computed successfully.
1595 */
1596int security_change_sid(u32 ssid,
1597 u32 tsid,
1598 u16 tclass,
1599 u32 *out_sid)
1600{
1601 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1602 out_sid, false);
1603}
1604
1605/* Clone the SID into the new SID table. */
1606static int clone_sid(u32 sid,
1607 struct context *context,
1608 void *arg)
1609{
1610 struct sidtab *s = arg;
1611
1612 if (sid > SECINITSID_NUM)
1613 return sidtab_insert(s, sid, context);
1614 else
1615 return 0;
1616}
1617
1618static inline int convert_context_handle_invalid_context(struct context *context)
1619{
1620 char *s;
1621 u32 len;
1622
1623 if (selinux_enforcing)
1624 return -EINVAL;
1625
1626 if (!context_struct_to_string(context, &s, &len)) {
1627 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s);
1628 kfree(s);
1629 }
1630 return 0;
1631}
1632
1633struct convert_context_args {
1634 struct policydb *oldp;
1635 struct policydb *newp;
1636};
1637
1638/*
1639 * Convert the values in the security context
1640 * structure `c' from the values specified
1641 * in the policy `p->oldp' to the values specified
1642 * in the policy `p->newp'. Verify that the
1643 * context is valid under the new policy.
1644 */
1645static int convert_context(u32 key,
1646 struct context *c,
1647 void *p)
1648{
1649 struct convert_context_args *args;
1650 struct context oldc;
1651 struct ocontext *oc;
1652 struct mls_range *range;
1653 struct role_datum *role;
1654 struct type_datum *typdatum;
1655 struct user_datum *usrdatum;
1656 char *s;
1657 u32 len;
1658 int rc = 0;
1659
1660 if (key <= SECINITSID_NUM)
1661 goto out;
1662
1663 args = p;
1664
1665 if (c->str) {
1666 struct context ctx;
1667
1668 rc = -ENOMEM;
1669 s = kstrdup(c->str, GFP_KERNEL);
1670 if (!s)
1671 goto out;
1672
1673 rc = string_to_context_struct(args->newp, NULL, s,
1674 c->len, &ctx, SECSID_NULL);
1675 kfree(s);
1676 if (!rc) {
1677 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n",
1678 c->str);
1679 /* Replace string with mapped representation. */
1680 kfree(c->str);
1681 memcpy(c, &ctx, sizeof(*c));
1682 goto out;
1683 } else if (rc == -EINVAL) {
1684 /* Retain string representation for later mapping. */
1685 rc = 0;
1686 goto out;
1687 } else {
1688 /* Other error condition, e.g. ENOMEM. */
1689 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n",
1690 c->str, -rc);
1691 goto out;
1692 }
1693 }
1694
1695 rc = context_cpy(&oldc, c);
1696 if (rc)
1697 goto out;
1698
1699 /* Convert the user. */
1700 rc = -EINVAL;
1701 usrdatum = hashtab_search(args->newp->p_users.table,
1702 sym_name(args->oldp, SYM_USERS, c->user - 1));
1703 if (!usrdatum)
1704 goto bad;
1705 c->user = usrdatum->value;
1706
1707 /* Convert the role. */
1708 rc = -EINVAL;
1709 role = hashtab_search(args->newp->p_roles.table,
1710 sym_name(args->oldp, SYM_ROLES, c->role - 1));
1711 if (!role)
1712 goto bad;
1713 c->role = role->value;
1714
1715 /* Convert the type. */
1716 rc = -EINVAL;
1717 typdatum = hashtab_search(args->newp->p_types.table,
1718 sym_name(args->oldp, SYM_TYPES, c->type - 1));
1719 if (!typdatum)
1720 goto bad;
1721 c->type = typdatum->value;
1722
1723 /* Convert the MLS fields if dealing with MLS policies */
1724 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1725 rc = mls_convert_context(args->oldp, args->newp, c);
1726 if (rc)
1727 goto bad;
1728 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1729 /*
1730 * Switching between MLS and non-MLS policy:
1731 * free any storage used by the MLS fields in the
1732 * context for all existing entries in the sidtab.
1733 */
1734 mls_context_destroy(c);
1735 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1736 /*
1737 * Switching between non-MLS and MLS policy:
1738 * ensure that the MLS fields of the context for all
1739 * existing entries in the sidtab are filled in with a
1740 * suitable default value, likely taken from one of the
1741 * initial SIDs.
1742 */
1743 oc = args->newp->ocontexts[OCON_ISID];
1744 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1745 oc = oc->next;
1746 rc = -EINVAL;
1747 if (!oc) {
1748 printk(KERN_ERR "SELinux: unable to look up"
1749 " the initial SIDs list\n");
1750 goto bad;
1751 }
1752 range = &oc->context[0].range;
1753 rc = mls_range_set(c, range);
1754 if (rc)
1755 goto bad;
1756 }
1757
1758 /* Check the validity of the new context. */
1759 if (!policydb_context_isvalid(args->newp, c)) {
1760 rc = convert_context_handle_invalid_context(&oldc);
1761 if (rc)
1762 goto bad;
1763 }
1764
1765 context_destroy(&oldc);
1766
1767 rc = 0;
1768out:
1769 return rc;
1770bad:
1771 /* Map old representation to string and save it. */
1772 rc = context_struct_to_string(&oldc, &s, &len);
1773 if (rc)
1774 return rc;
1775 context_destroy(&oldc);
1776 context_destroy(c);
1777 c->str = s;
1778 c->len = len;
1779 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n",
1780 c->str);
1781 rc = 0;
1782 goto out;
1783}
1784
1785static void security_load_policycaps(void)
1786{
1787 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1788 POLICYDB_CAPABILITY_NETPEER);
1789 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1790 POLICYDB_CAPABILITY_OPENPERM);
1791}
1792
1793extern void selinux_complete_init(void);
1794static int security_preserve_bools(struct policydb *p);
1795
1796/**
1797 * security_load_policy - Load a security policy configuration.
1798 * @data: binary policy data
1799 * @len: length of data in bytes
1800 *
1801 * Load a new set of security policy configuration data,
1802 * validate it and convert the SID table as necessary.
1803 * This function will flush the access vector cache after
1804 * loading the new policy.
1805 */
1806int security_load_policy(void *data, size_t len)
1807{
1808 struct policydb oldpolicydb, newpolicydb;
1809 struct sidtab oldsidtab, newsidtab;
1810 struct selinux_mapping *oldmap, *map = NULL;
1811 struct convert_context_args args;
1812 u32 seqno;
1813 u16 map_size;
1814 int rc = 0;
1815 struct policy_file file = { data, len }, *fp = &file;
1816
1817 if (!ss_initialized) {
1818 avtab_cache_init();
1819 rc = policydb_read(&policydb, fp);
1820 if (rc) {
1821 avtab_cache_destroy();
1822 return rc;
1823 }
1824
1825 policydb.len = len;
1826 rc = selinux_set_mapping(&policydb, secclass_map,
1827 ¤t_mapping,
1828 ¤t_mapping_size);
1829 if (rc) {
1830 policydb_destroy(&policydb);
1831 avtab_cache_destroy();
1832 return rc;
1833 }
1834
1835 rc = policydb_load_isids(&policydb, &sidtab);
1836 if (rc) {
1837 policydb_destroy(&policydb);
1838 avtab_cache_destroy();
1839 return rc;
1840 }
1841
1842 security_load_policycaps();
1843 ss_initialized = 1;
1844 seqno = ++latest_granting;
1845 selinux_complete_init();
1846 avc_ss_reset(seqno);
1847 selnl_notify_policyload(seqno);
1848 selinux_status_update_policyload(seqno);
1849 selinux_netlbl_cache_invalidate();
1850 selinux_xfrm_notify_policyload();
1851 return 0;
1852 }
1853
1854#if 0
1855 sidtab_hash_eval(&sidtab, "sids");
1856#endif
1857
1858 rc = policydb_read(&newpolicydb, fp);
1859 if (rc)
1860 return rc;
1861
1862 newpolicydb.len = len;
1863 /* If switching between different policy types, log MLS status */
1864 if (policydb.mls_enabled && !newpolicydb.mls_enabled)
1865 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
1866 else if (!policydb.mls_enabled && newpolicydb.mls_enabled)
1867 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
1868
1869 rc = policydb_load_isids(&newpolicydb, &newsidtab);
1870 if (rc) {
1871 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
1872 policydb_destroy(&newpolicydb);
1873 return rc;
1874 }
1875
1876 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size);
1877 if (rc)
1878 goto err;
1879
1880 rc = security_preserve_bools(&newpolicydb);
1881 if (rc) {
1882 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
1883 goto err;
1884 }
1885
1886 /* Clone the SID table. */
1887 sidtab_shutdown(&sidtab);
1888
1889 rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
1890 if (rc)
1891 goto err;
1892
1893 /*
1894 * Convert the internal representations of contexts
1895 * in the new SID table.
1896 */
1897 args.oldp = &policydb;
1898 args.newp = &newpolicydb;
1899 rc = sidtab_map(&newsidtab, convert_context, &args);
1900 if (rc) {
1901 printk(KERN_ERR "SELinux: unable to convert the internal"
1902 " representation of contexts in the new SID"
1903 " table\n");
1904 goto err;
1905 }
1906
1907 /* Save the old policydb and SID table to free later. */
1908 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1909 sidtab_set(&oldsidtab, &sidtab);
1910
1911 /* Install the new policydb and SID table. */
1912 write_lock_irq(&policy_rwlock);
1913 memcpy(&policydb, &newpolicydb, sizeof policydb);
1914 sidtab_set(&sidtab, &newsidtab);
1915 security_load_policycaps();
1916 oldmap = current_mapping;
1917 current_mapping = map;
1918 current_mapping_size = map_size;
1919 seqno = ++latest_granting;
1920 write_unlock_irq(&policy_rwlock);
1921
1922 /* Free the old policydb and SID table. */
1923 policydb_destroy(&oldpolicydb);
1924 sidtab_destroy(&oldsidtab);
1925 kfree(oldmap);
1926
1927 avc_ss_reset(seqno);
1928 selnl_notify_policyload(seqno);
1929 selinux_status_update_policyload(seqno);
1930 selinux_netlbl_cache_invalidate();
1931 selinux_xfrm_notify_policyload();
1932
1933 return 0;
1934
1935err:
1936 kfree(map);
1937 sidtab_destroy(&newsidtab);
1938 policydb_destroy(&newpolicydb);
1939 return rc;
1940
1941}
1942
1943size_t security_policydb_len(void)
1944{
1945 size_t len;
1946
1947 read_lock(&policy_rwlock);
1948 len = policydb.len;
1949 read_unlock(&policy_rwlock);
1950
1951 return len;
1952}
1953
1954/**
1955 * security_port_sid - Obtain the SID for a port.
1956 * @protocol: protocol number
1957 * @port: port number
1958 * @out_sid: security identifier
1959 */
1960int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1961{
1962 struct ocontext *c;
1963 int rc = 0;
1964
1965 read_lock(&policy_rwlock);
1966
1967 c = policydb.ocontexts[OCON_PORT];
1968 while (c) {
1969 if (c->u.port.protocol == protocol &&
1970 c->u.port.low_port <= port &&
1971 c->u.port.high_port >= port)
1972 break;
1973 c = c->next;
1974 }
1975
1976 if (c) {
1977 if (!c->sid[0]) {
1978 rc = sidtab_context_to_sid(&sidtab,
1979 &c->context[0],
1980 &c->sid[0]);
1981 if (rc)
1982 goto out;
1983 }
1984 *out_sid = c->sid[0];
1985 } else {
1986 *out_sid = SECINITSID_PORT;
1987 }
1988
1989out:
1990 read_unlock(&policy_rwlock);
1991 return rc;
1992}
1993
1994/**
1995 * security_netif_sid - Obtain the SID for a network interface.
1996 * @name: interface name
1997 * @if_sid: interface SID
1998 */
1999int security_netif_sid(char *name, u32 *if_sid)
2000{
2001 int rc = 0;
2002 struct ocontext *c;
2003
2004 read_lock(&policy_rwlock);
2005
2006 c = policydb.ocontexts[OCON_NETIF];
2007 while (c) {
2008 if (strcmp(name, c->u.name) == 0)
2009 break;
2010 c = c->next;
2011 }
2012
2013 if (c) {
2014 if (!c->sid[0] || !c->sid[1]) {
2015 rc = sidtab_context_to_sid(&sidtab,
2016 &c->context[0],
2017 &c->sid[0]);
2018 if (rc)
2019 goto out;
2020 rc = sidtab_context_to_sid(&sidtab,
2021 &c->context[1],
2022 &c->sid[1]);
2023 if (rc)
2024 goto out;
2025 }
2026 *if_sid = c->sid[0];
2027 } else
2028 *if_sid = SECINITSID_NETIF;
2029
2030out:
2031 read_unlock(&policy_rwlock);
2032 return rc;
2033}
2034
2035static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2036{
2037 int i, fail = 0;
2038
2039 for (i = 0; i < 4; i++)
2040 if (addr[i] != (input[i] & mask[i])) {
2041 fail = 1;
2042 break;
2043 }
2044
2045 return !fail;
2046}
2047
2048/**
2049 * security_node_sid - Obtain the SID for a node (host).
2050 * @domain: communication domain aka address family
2051 * @addrp: address
2052 * @addrlen: address length in bytes
2053 * @out_sid: security identifier
2054 */
2055int security_node_sid(u16 domain,
2056 void *addrp,
2057 u32 addrlen,
2058 u32 *out_sid)
2059{
2060 int rc;
2061 struct ocontext *c;
2062
2063 read_lock(&policy_rwlock);
2064
2065 switch (domain) {
2066 case AF_INET: {
2067 u32 addr;
2068
2069 rc = -EINVAL;
2070 if (addrlen != sizeof(u32))
2071 goto out;
2072
2073 addr = *((u32 *)addrp);
2074
2075 c = policydb.ocontexts[OCON_NODE];
2076 while (c) {
2077 if (c->u.node.addr == (addr & c->u.node.mask))
2078 break;
2079 c = c->next;
2080 }
2081 break;
2082 }
2083
2084 case AF_INET6:
2085 rc = -EINVAL;
2086 if (addrlen != sizeof(u64) * 2)
2087 goto out;
2088 c = policydb.ocontexts[OCON_NODE6];
2089 while (c) {
2090 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2091 c->u.node6.mask))
2092 break;
2093 c = c->next;
2094 }
2095 break;
2096
2097 default:
2098 rc = 0;
2099 *out_sid = SECINITSID_NODE;
2100 goto out;
2101 }
2102
2103 if (c) {
2104 if (!c->sid[0]) {
2105 rc = sidtab_context_to_sid(&sidtab,
2106 &c->context[0],
2107 &c->sid[0]);
2108 if (rc)
2109 goto out;
2110 }
2111 *out_sid = c->sid[0];
2112 } else {
2113 *out_sid = SECINITSID_NODE;
2114 }
2115
2116 rc = 0;
2117out:
2118 read_unlock(&policy_rwlock);
2119 return rc;
2120}
2121
2122#define SIDS_NEL 25
2123
2124/**
2125 * security_get_user_sids - Obtain reachable SIDs for a user.
2126 * @fromsid: starting SID
2127 * @username: username
2128 * @sids: array of reachable SIDs for user
2129 * @nel: number of elements in @sids
2130 *
2131 * Generate the set of SIDs for legal security contexts
2132 * for a given user that can be reached by @fromsid.
2133 * Set *@sids to point to a dynamically allocated
2134 * array containing the set of SIDs. Set *@nel to the
2135 * number of elements in the array.
2136 */
2137
2138int security_get_user_sids(u32 fromsid,
2139 char *username,
2140 u32 **sids,
2141 u32 *nel)
2142{
2143 struct context *fromcon, usercon;
2144 u32 *mysids = NULL, *mysids2, sid;
2145 u32 mynel = 0, maxnel = SIDS_NEL;
2146 struct user_datum *user;
2147 struct role_datum *role;
2148 struct ebitmap_node *rnode, *tnode;
2149 int rc = 0, i, j;
2150
2151 *sids = NULL;
2152 *nel = 0;
2153
2154 if (!ss_initialized)
2155 goto out;
2156
2157 read_lock(&policy_rwlock);
2158
2159 context_init(&usercon);
2160
2161 rc = -EINVAL;
2162 fromcon = sidtab_search(&sidtab, fromsid);
2163 if (!fromcon)
2164 goto out_unlock;
2165
2166 rc = -EINVAL;
2167 user = hashtab_search(policydb.p_users.table, username);
2168 if (!user)
2169 goto out_unlock;
2170
2171 usercon.user = user->value;
2172
2173 rc = -ENOMEM;
2174 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2175 if (!mysids)
2176 goto out_unlock;
2177
2178 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2179 role = policydb.role_val_to_struct[i];
2180 usercon.role = i + 1;
2181 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2182 usercon.type = j + 1;
2183
2184 if (mls_setup_user_range(fromcon, user, &usercon))
2185 continue;
2186
2187 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2188 if (rc)
2189 goto out_unlock;
2190 if (mynel < maxnel) {
2191 mysids[mynel++] = sid;
2192 } else {
2193 rc = -ENOMEM;
2194 maxnel += SIDS_NEL;
2195 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2196 if (!mysids2)
2197 goto out_unlock;
2198 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2199 kfree(mysids);
2200 mysids = mysids2;
2201 mysids[mynel++] = sid;
2202 }
2203 }
2204 }
2205 rc = 0;
2206out_unlock:
2207 read_unlock(&policy_rwlock);
2208 if (rc || !mynel) {
2209 kfree(mysids);
2210 goto out;
2211 }
2212
2213 rc = -ENOMEM;
2214 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2215 if (!mysids2) {
2216 kfree(mysids);
2217 goto out;
2218 }
2219 for (i = 0, j = 0; i < mynel; i++) {
2220 struct av_decision dummy_avd;
2221 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2222 SECCLASS_PROCESS, /* kernel value */
2223 PROCESS__TRANSITION, AVC_STRICT,
2224 &dummy_avd);
2225 if (!rc)
2226 mysids2[j++] = mysids[i];
2227 cond_resched();
2228 }
2229 rc = 0;
2230 kfree(mysids);
2231 *sids = mysids2;
2232 *nel = j;
2233out:
2234 return rc;
2235}
2236
2237/**
2238 * security_genfs_sid - Obtain a SID for a file in a filesystem
2239 * @fstype: filesystem type
2240 * @path: path from root of mount
2241 * @sclass: file security class
2242 * @sid: SID for path
2243 *
2244 * Obtain a SID to use for a file in a filesystem that
2245 * cannot support xattr or use a fixed labeling behavior like
2246 * transition SIDs or task SIDs.
2247 */
2248int security_genfs_sid(const char *fstype,
2249 char *path,
2250 u16 orig_sclass,
2251 u32 *sid)
2252{
2253 int len;
2254 u16 sclass;
2255 struct genfs *genfs;
2256 struct ocontext *c;
2257 int rc, cmp = 0;
2258
2259 while (path[0] == '/' && path[1] == '/')
2260 path++;
2261
2262 read_lock(&policy_rwlock);
2263
2264 sclass = unmap_class(orig_sclass);
2265 *sid = SECINITSID_UNLABELED;
2266
2267 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2268 cmp = strcmp(fstype, genfs->fstype);
2269 if (cmp <= 0)
2270 break;
2271 }
2272
2273 rc = -ENOENT;
2274 if (!genfs || cmp)
2275 goto out;
2276
2277 for (c = genfs->head; c; c = c->next) {
2278 len = strlen(c->u.name);
2279 if ((!c->v.sclass || sclass == c->v.sclass) &&
2280 (strncmp(c->u.name, path, len) == 0))
2281 break;
2282 }
2283
2284 rc = -ENOENT;
2285 if (!c)
2286 goto out;
2287
2288 if (!c->sid[0]) {
2289 rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]);
2290 if (rc)
2291 goto out;
2292 }
2293
2294 *sid = c->sid[0];
2295 rc = 0;
2296out:
2297 read_unlock(&policy_rwlock);
2298 return rc;
2299}
2300
2301/**
2302 * security_fs_use - Determine how to handle labeling for a filesystem.
2303 * @fstype: filesystem type
2304 * @behavior: labeling behavior
2305 * @sid: SID for filesystem (superblock)
2306 */
2307int security_fs_use(
2308 const char *fstype,
2309 unsigned int *behavior,
2310 u32 *sid)
2311{
2312 int rc = 0;
2313 struct ocontext *c;
2314
2315 read_lock(&policy_rwlock);
2316
2317 c = policydb.ocontexts[OCON_FSUSE];
2318 while (c) {
2319 if (strcmp(fstype, c->u.name) == 0)
2320 break;
2321 c = c->next;
2322 }
2323
2324 if (c) {
2325 *behavior = c->v.behavior;
2326 if (!c->sid[0]) {
2327 rc = sidtab_context_to_sid(&sidtab, &c->context[0],
2328 &c->sid[0]);
2329 if (rc)
2330 goto out;
2331 }
2332 *sid = c->sid[0];
2333 } else {
2334 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
2335 if (rc) {
2336 *behavior = SECURITY_FS_USE_NONE;
2337 rc = 0;
2338 } else {
2339 *behavior = SECURITY_FS_USE_GENFS;
2340 }
2341 }
2342
2343out:
2344 read_unlock(&policy_rwlock);
2345 return rc;
2346}
2347
2348int security_get_bools(int *len, char ***names, int **values)
2349{
2350 int i, rc;
2351
2352 read_lock(&policy_rwlock);
2353 *names = NULL;
2354 *values = NULL;
2355
2356 rc = 0;
2357 *len = policydb.p_bools.nprim;
2358 if (!*len)
2359 goto out;
2360
2361 rc = -ENOMEM;
2362 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2363 if (!*names)
2364 goto err;
2365
2366 rc = -ENOMEM;
2367 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2368 if (!*values)
2369 goto err;
2370
2371 for (i = 0; i < *len; i++) {
2372 size_t name_len;
2373
2374 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2375 name_len = strlen(sym_name(&policydb, SYM_BOOLS, i)) + 1;
2376
2377 rc = -ENOMEM;
2378 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
2379 if (!(*names)[i])
2380 goto err;
2381
2382 strncpy((*names)[i], sym_name(&policydb, SYM_BOOLS, i), name_len);
2383 (*names)[i][name_len - 1] = 0;
2384 }
2385 rc = 0;
2386out:
2387 read_unlock(&policy_rwlock);
2388 return rc;
2389err:
2390 if (*names) {
2391 for (i = 0; i < *len; i++)
2392 kfree((*names)[i]);
2393 }
2394 kfree(*values);
2395 goto out;
2396}
2397
2398
2399int security_set_bools(int len, int *values)
2400{
2401 int i, rc;
2402 int lenp, seqno = 0;
2403 struct cond_node *cur;
2404
2405 write_lock_irq(&policy_rwlock);
2406
2407 rc = -EFAULT;
2408 lenp = policydb.p_bools.nprim;
2409 if (len != lenp)
2410 goto out;
2411
2412 for (i = 0; i < len; i++) {
2413 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2414 audit_log(current->audit_context, GFP_ATOMIC,
2415 AUDIT_MAC_CONFIG_CHANGE,
2416 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2417 sym_name(&policydb, SYM_BOOLS, i),
2418 !!values[i],
2419 policydb.bool_val_to_struct[i]->state,
2420 audit_get_loginuid(current),
2421 audit_get_sessionid(current));
2422 }
2423 if (values[i])
2424 policydb.bool_val_to_struct[i]->state = 1;
2425 else
2426 policydb.bool_val_to_struct[i]->state = 0;
2427 }
2428
2429 for (cur = policydb.cond_list; cur; cur = cur->next) {
2430 rc = evaluate_cond_node(&policydb, cur);
2431 if (rc)
2432 goto out;
2433 }
2434
2435 seqno = ++latest_granting;
2436 rc = 0;
2437out:
2438 write_unlock_irq(&policy_rwlock);
2439 if (!rc) {
2440 avc_ss_reset(seqno);
2441 selnl_notify_policyload(seqno);
2442 selinux_status_update_policyload(seqno);
2443 selinux_xfrm_notify_policyload();
2444 }
2445 return rc;
2446}
2447
2448int security_get_bool_value(int bool)
2449{
2450 int rc;
2451 int len;
2452
2453 read_lock(&policy_rwlock);
2454
2455 rc = -EFAULT;
2456 len = policydb.p_bools.nprim;
2457 if (bool >= len)
2458 goto out;
2459
2460 rc = policydb.bool_val_to_struct[bool]->state;
2461out:
2462 read_unlock(&policy_rwlock);
2463 return rc;
2464}
2465
2466static int security_preserve_bools(struct policydb *p)
2467{
2468 int rc, nbools = 0, *bvalues = NULL, i;
2469 char **bnames = NULL;
2470 struct cond_bool_datum *booldatum;
2471 struct cond_node *cur;
2472
2473 rc = security_get_bools(&nbools, &bnames, &bvalues);
2474 if (rc)
2475 goto out;
2476 for (i = 0; i < nbools; i++) {
2477 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2478 if (booldatum)
2479 booldatum->state = bvalues[i];
2480 }
2481 for (cur = p->cond_list; cur; cur = cur->next) {
2482 rc = evaluate_cond_node(p, cur);
2483 if (rc)
2484 goto out;
2485 }
2486
2487out:
2488 if (bnames) {
2489 for (i = 0; i < nbools; i++)
2490 kfree(bnames[i]);
2491 }
2492 kfree(bnames);
2493 kfree(bvalues);
2494 return rc;
2495}
2496
2497/*
2498 * security_sid_mls_copy() - computes a new sid based on the given
2499 * sid and the mls portion of mls_sid.
2500 */
2501int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2502{
2503 struct context *context1;
2504 struct context *context2;
2505 struct context newcon;
2506 char *s;
2507 u32 len;
2508 int rc;
2509
2510 rc = 0;
2511 if (!ss_initialized || !policydb.mls_enabled) {
2512 *new_sid = sid;
2513 goto out;
2514 }
2515
2516 context_init(&newcon);
2517
2518 read_lock(&policy_rwlock);
2519
2520 rc = -EINVAL;
2521 context1 = sidtab_search(&sidtab, sid);
2522 if (!context1) {
2523 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2524 __func__, sid);
2525 goto out_unlock;
2526 }
2527
2528 rc = -EINVAL;
2529 context2 = sidtab_search(&sidtab, mls_sid);
2530 if (!context2) {
2531 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2532 __func__, mls_sid);
2533 goto out_unlock;
2534 }
2535
2536 newcon.user = context1->user;
2537 newcon.role = context1->role;
2538 newcon.type = context1->type;
2539 rc = mls_context_cpy(&newcon, context2);
2540 if (rc)
2541 goto out_unlock;
2542
2543 /* Check the validity of the new context. */
2544 if (!policydb_context_isvalid(&policydb, &newcon)) {
2545 rc = convert_context_handle_invalid_context(&newcon);
2546 if (rc) {
2547 if (!context_struct_to_string(&newcon, &s, &len)) {
2548 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2549 "security_sid_mls_copy: invalid context %s", s);
2550 kfree(s);
2551 }
2552 goto out_unlock;
2553 }
2554 }
2555
2556 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2557out_unlock:
2558 read_unlock(&policy_rwlock);
2559 context_destroy(&newcon);
2560out:
2561 return rc;
2562}
2563
2564/**
2565 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2566 * @nlbl_sid: NetLabel SID
2567 * @nlbl_type: NetLabel labeling protocol type
2568 * @xfrm_sid: XFRM SID
2569 *
2570 * Description:
2571 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2572 * resolved into a single SID it is returned via @peer_sid and the function
2573 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
2574 * returns a negative value. A table summarizing the behavior is below:
2575 *
2576 * | function return | @sid
2577 * ------------------------------+-----------------+-----------------
2578 * no peer labels | 0 | SECSID_NULL
2579 * single peer label | 0 | <peer_label>
2580 * multiple, consistent labels | 0 | <peer_label>
2581 * multiple, inconsistent labels | -<errno> | SECSID_NULL
2582 *
2583 */
2584int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2585 u32 xfrm_sid,
2586 u32 *peer_sid)
2587{
2588 int rc;
2589 struct context *nlbl_ctx;
2590 struct context *xfrm_ctx;
2591
2592 *peer_sid = SECSID_NULL;
2593
2594 /* handle the common (which also happens to be the set of easy) cases
2595 * right away, these two if statements catch everything involving a
2596 * single or absent peer SID/label */
2597 if (xfrm_sid == SECSID_NULL) {
2598 *peer_sid = nlbl_sid;
2599 return 0;
2600 }
2601 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2602 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2603 * is present */
2604 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2605 *peer_sid = xfrm_sid;
2606 return 0;
2607 }
2608
2609 /* we don't need to check ss_initialized here since the only way both
2610 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2611 * security server was initialized and ss_initialized was true */
2612 if (!policydb.mls_enabled)
2613 return 0;
2614
2615 read_lock(&policy_rwlock);
2616
2617 rc = -EINVAL;
2618 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2619 if (!nlbl_ctx) {
2620 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2621 __func__, nlbl_sid);
2622 goto out;
2623 }
2624 rc = -EINVAL;
2625 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2626 if (!xfrm_ctx) {
2627 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2628 __func__, xfrm_sid);
2629 goto out;
2630 }
2631 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2632 if (rc)
2633 goto out;
2634
2635 /* at present NetLabel SIDs/labels really only carry MLS
2636 * information so if the MLS portion of the NetLabel SID
2637 * matches the MLS portion of the labeled XFRM SID/label
2638 * then pass along the XFRM SID as it is the most
2639 * expressive */
2640 *peer_sid = xfrm_sid;
2641out:
2642 read_unlock(&policy_rwlock);
2643 return rc;
2644}
2645
2646static int get_classes_callback(void *k, void *d, void *args)
2647{
2648 struct class_datum *datum = d;
2649 char *name = k, **classes = args;
2650 int value = datum->value - 1;
2651
2652 classes[value] = kstrdup(name, GFP_ATOMIC);
2653 if (!classes[value])
2654 return -ENOMEM;
2655
2656 return 0;
2657}
2658
2659int security_get_classes(char ***classes, int *nclasses)
2660{
2661 int rc;
2662
2663 read_lock(&policy_rwlock);
2664
2665 rc = -ENOMEM;
2666 *nclasses = policydb.p_classes.nprim;
2667 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
2668 if (!*classes)
2669 goto out;
2670
2671 rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2672 *classes);
2673 if (rc) {
2674 int i;
2675 for (i = 0; i < *nclasses; i++)
2676 kfree((*classes)[i]);
2677 kfree(*classes);
2678 }
2679
2680out:
2681 read_unlock(&policy_rwlock);
2682 return rc;
2683}
2684
2685static int get_permissions_callback(void *k, void *d, void *args)
2686{
2687 struct perm_datum *datum = d;
2688 char *name = k, **perms = args;
2689 int value = datum->value - 1;
2690
2691 perms[value] = kstrdup(name, GFP_ATOMIC);
2692 if (!perms[value])
2693 return -ENOMEM;
2694
2695 return 0;
2696}
2697
2698int security_get_permissions(char *class, char ***perms, int *nperms)
2699{
2700 int rc, i;
2701 struct class_datum *match;
2702
2703 read_lock(&policy_rwlock);
2704
2705 rc = -EINVAL;
2706 match = hashtab_search(policydb.p_classes.table, class);
2707 if (!match) {
2708 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
2709 __func__, class);
2710 goto out;
2711 }
2712
2713 rc = -ENOMEM;
2714 *nperms = match->permissions.nprim;
2715 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
2716 if (!*perms)
2717 goto out;
2718
2719 if (match->comdatum) {
2720 rc = hashtab_map(match->comdatum->permissions.table,
2721 get_permissions_callback, *perms);
2722 if (rc)
2723 goto err;
2724 }
2725
2726 rc = hashtab_map(match->permissions.table, get_permissions_callback,
2727 *perms);
2728 if (rc)
2729 goto err;
2730
2731out:
2732 read_unlock(&policy_rwlock);
2733 return rc;
2734
2735err:
2736 read_unlock(&policy_rwlock);
2737 for (i = 0; i < *nperms; i++)
2738 kfree((*perms)[i]);
2739 kfree(*perms);
2740 return rc;
2741}
2742
2743int security_get_reject_unknown(void)
2744{
2745 return policydb.reject_unknown;
2746}
2747
2748int security_get_allow_unknown(void)
2749{
2750 return policydb.allow_unknown;
2751}
2752
2753/**
2754 * security_policycap_supported - Check for a specific policy capability
2755 * @req_cap: capability
2756 *
2757 * Description:
2758 * This function queries the currently loaded policy to see if it supports the
2759 * capability specified by @req_cap. Returns true (1) if the capability is
2760 * supported, false (0) if it isn't supported.
2761 *
2762 */
2763int security_policycap_supported(unsigned int req_cap)
2764{
2765 int rc;
2766
2767 read_lock(&policy_rwlock);
2768 rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2769 read_unlock(&policy_rwlock);
2770
2771 return rc;
2772}
2773
2774struct selinux_audit_rule {
2775 u32 au_seqno;
2776 struct context au_ctxt;
2777};
2778
2779void selinux_audit_rule_free(void *vrule)
2780{
2781 struct selinux_audit_rule *rule = vrule;
2782
2783 if (rule) {
2784 context_destroy(&rule->au_ctxt);
2785 kfree(rule);
2786 }
2787}
2788
2789int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2790{
2791 struct selinux_audit_rule *tmprule;
2792 struct role_datum *roledatum;
2793 struct type_datum *typedatum;
2794 struct user_datum *userdatum;
2795 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2796 int rc = 0;
2797
2798 *rule = NULL;
2799
2800 if (!ss_initialized)
2801 return -EOPNOTSUPP;
2802
2803 switch (field) {
2804 case AUDIT_SUBJ_USER:
2805 case AUDIT_SUBJ_ROLE:
2806 case AUDIT_SUBJ_TYPE:
2807 case AUDIT_OBJ_USER:
2808 case AUDIT_OBJ_ROLE:
2809 case AUDIT_OBJ_TYPE:
2810 /* only 'equals' and 'not equals' fit user, role, and type */
2811 if (op != Audit_equal && op != Audit_not_equal)
2812 return -EINVAL;
2813 break;
2814 case AUDIT_SUBJ_SEN:
2815 case AUDIT_SUBJ_CLR:
2816 case AUDIT_OBJ_LEV_LOW:
2817 case AUDIT_OBJ_LEV_HIGH:
2818 /* we do not allow a range, indicated by the presence of '-' */
2819 if (strchr(rulestr, '-'))
2820 return -EINVAL;
2821 break;
2822 default:
2823 /* only the above fields are valid */
2824 return -EINVAL;
2825 }
2826
2827 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2828 if (!tmprule)
2829 return -ENOMEM;
2830
2831 context_init(&tmprule->au_ctxt);
2832
2833 read_lock(&policy_rwlock);
2834
2835 tmprule->au_seqno = latest_granting;
2836
2837 switch (field) {
2838 case AUDIT_SUBJ_USER:
2839 case AUDIT_OBJ_USER:
2840 rc = -EINVAL;
2841 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2842 if (!userdatum)
2843 goto out;
2844 tmprule->au_ctxt.user = userdatum->value;
2845 break;
2846 case AUDIT_SUBJ_ROLE:
2847 case AUDIT_OBJ_ROLE:
2848 rc = -EINVAL;
2849 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2850 if (!roledatum)
2851 goto out;
2852 tmprule->au_ctxt.role = roledatum->value;
2853 break;
2854 case AUDIT_SUBJ_TYPE:
2855 case AUDIT_OBJ_TYPE:
2856 rc = -EINVAL;
2857 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2858 if (!typedatum)
2859 goto out;
2860 tmprule->au_ctxt.type = typedatum->value;
2861 break;
2862 case AUDIT_SUBJ_SEN:
2863 case AUDIT_SUBJ_CLR:
2864 case AUDIT_OBJ_LEV_LOW:
2865 case AUDIT_OBJ_LEV_HIGH:
2866 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2867 if (rc)
2868 goto out;
2869 break;
2870 }
2871 rc = 0;
2872out:
2873 read_unlock(&policy_rwlock);
2874
2875 if (rc) {
2876 selinux_audit_rule_free(tmprule);
2877 tmprule = NULL;
2878 }
2879
2880 *rule = tmprule;
2881
2882 return rc;
2883}
2884
2885/* Check to see if the rule contains any selinux fields */
2886int selinux_audit_rule_known(struct audit_krule *rule)
2887{
2888 int i;
2889
2890 for (i = 0; i < rule->field_count; i++) {
2891 struct audit_field *f = &rule->fields[i];
2892 switch (f->type) {
2893 case AUDIT_SUBJ_USER:
2894 case AUDIT_SUBJ_ROLE:
2895 case AUDIT_SUBJ_TYPE:
2896 case AUDIT_SUBJ_SEN:
2897 case AUDIT_SUBJ_CLR:
2898 case AUDIT_OBJ_USER:
2899 case AUDIT_OBJ_ROLE:
2900 case AUDIT_OBJ_TYPE:
2901 case AUDIT_OBJ_LEV_LOW:
2902 case AUDIT_OBJ_LEV_HIGH:
2903 return 1;
2904 }
2905 }
2906
2907 return 0;
2908}
2909
2910int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2911 struct audit_context *actx)
2912{
2913 struct context *ctxt;
2914 struct mls_level *level;
2915 struct selinux_audit_rule *rule = vrule;
2916 int match = 0;
2917
2918 if (!rule) {
2919 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2920 "selinux_audit_rule_match: missing rule\n");
2921 return -ENOENT;
2922 }
2923
2924 read_lock(&policy_rwlock);
2925
2926 if (rule->au_seqno < latest_granting) {
2927 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2928 "selinux_audit_rule_match: stale rule\n");
2929 match = -ESTALE;
2930 goto out;
2931 }
2932
2933 ctxt = sidtab_search(&sidtab, sid);
2934 if (!ctxt) {
2935 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2936 "selinux_audit_rule_match: unrecognized SID %d\n",
2937 sid);
2938 match = -ENOENT;
2939 goto out;
2940 }
2941
2942 /* a field/op pair that is not caught here will simply fall through
2943 without a match */
2944 switch (field) {
2945 case AUDIT_SUBJ_USER:
2946 case AUDIT_OBJ_USER:
2947 switch (op) {
2948 case Audit_equal:
2949 match = (ctxt->user == rule->au_ctxt.user);
2950 break;
2951 case Audit_not_equal:
2952 match = (ctxt->user != rule->au_ctxt.user);
2953 break;
2954 }
2955 break;
2956 case AUDIT_SUBJ_ROLE:
2957 case AUDIT_OBJ_ROLE:
2958 switch (op) {
2959 case Audit_equal:
2960 match = (ctxt->role == rule->au_ctxt.role);
2961 break;
2962 case Audit_not_equal:
2963 match = (ctxt->role != rule->au_ctxt.role);
2964 break;
2965 }
2966 break;
2967 case AUDIT_SUBJ_TYPE:
2968 case AUDIT_OBJ_TYPE:
2969 switch (op) {
2970 case Audit_equal:
2971 match = (ctxt->type == rule->au_ctxt.type);
2972 break;
2973 case Audit_not_equal:
2974 match = (ctxt->type != rule->au_ctxt.type);
2975 break;
2976 }
2977 break;
2978 case AUDIT_SUBJ_SEN:
2979 case AUDIT_SUBJ_CLR:
2980 case AUDIT_OBJ_LEV_LOW:
2981 case AUDIT_OBJ_LEV_HIGH:
2982 level = ((field == AUDIT_SUBJ_SEN ||
2983 field == AUDIT_OBJ_LEV_LOW) ?
2984 &ctxt->range.level[0] : &ctxt->range.level[1]);
2985 switch (op) {
2986 case Audit_equal:
2987 match = mls_level_eq(&rule->au_ctxt.range.level[0],
2988 level);
2989 break;
2990 case Audit_not_equal:
2991 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2992 level);
2993 break;
2994 case Audit_lt:
2995 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2996 level) &&
2997 !mls_level_eq(&rule->au_ctxt.range.level[0],
2998 level));
2999 break;
3000 case Audit_le:
3001 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3002 level);
3003 break;
3004 case Audit_gt:
3005 match = (mls_level_dom(level,
3006 &rule->au_ctxt.range.level[0]) &&
3007 !mls_level_eq(level,
3008 &rule->au_ctxt.range.level[0]));
3009 break;
3010 case Audit_ge:
3011 match = mls_level_dom(level,
3012 &rule->au_ctxt.range.level[0]);
3013 break;
3014 }
3015 }
3016
3017out:
3018 read_unlock(&policy_rwlock);
3019 return match;
3020}
3021
3022static int (*aurule_callback)(void) = audit_update_lsm_rules;
3023
3024static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
3025 u16 class, u32 perms, u32 *retained)
3026{
3027 int err = 0;
3028
3029 if (event == AVC_CALLBACK_RESET && aurule_callback)
3030 err = aurule_callback();
3031 return err;
3032}
3033
3034static int __init aurule_init(void)
3035{
3036 int err;
3037
3038 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
3039 SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
3040 if (err)
3041 panic("avc_add_callback() failed, error %d\n", err);
3042
3043 return err;
3044}
3045__initcall(aurule_init);
3046
3047#ifdef CONFIG_NETLABEL
3048/**
3049 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3050 * @secattr: the NetLabel packet security attributes
3051 * @sid: the SELinux SID
3052 *
3053 * Description:
3054 * Attempt to cache the context in @ctx, which was derived from the packet in
3055 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3056 * already been initialized.
3057 *
3058 */
3059static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3060 u32 sid)
3061{
3062 u32 *sid_cache;
3063
3064 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3065 if (sid_cache == NULL)
3066 return;
3067 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3068 if (secattr->cache == NULL) {
3069 kfree(sid_cache);
3070 return;
3071 }
3072
3073 *sid_cache = sid;
3074 secattr->cache->free = kfree;
3075 secattr->cache->data = sid_cache;
3076 secattr->flags |= NETLBL_SECATTR_CACHE;
3077}
3078
3079/**
3080 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3081 * @secattr: the NetLabel packet security attributes
3082 * @sid: the SELinux SID
3083 *
3084 * Description:
3085 * Convert the given NetLabel security attributes in @secattr into a
3086 * SELinux SID. If the @secattr field does not contain a full SELinux
3087 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3088 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3089 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3090 * conversion for future lookups. Returns zero on success, negative values on
3091 * failure.
3092 *
3093 */
3094int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3095 u32 *sid)
3096{
3097 int rc;
3098 struct context *ctx;
3099 struct context ctx_new;
3100
3101 if (!ss_initialized) {
3102 *sid = SECSID_NULL;
3103 return 0;
3104 }
3105
3106 read_lock(&policy_rwlock);
3107
3108 if (secattr->flags & NETLBL_SECATTR_CACHE)
3109 *sid = *(u32 *)secattr->cache->data;
3110 else if (secattr->flags & NETLBL_SECATTR_SECID)
3111 *sid = secattr->attr.secid;
3112 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3113 rc = -EIDRM;
3114 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3115 if (ctx == NULL)
3116 goto out;
3117
3118 context_init(&ctx_new);
3119 ctx_new.user = ctx->user;
3120 ctx_new.role = ctx->role;
3121 ctx_new.type = ctx->type;
3122 mls_import_netlbl_lvl(&ctx_new, secattr);
3123 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3124 rc = ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
3125 secattr->attr.mls.cat);
3126 if (rc)
3127 goto out;
3128 memcpy(&ctx_new.range.level[1].cat,
3129 &ctx_new.range.level[0].cat,
3130 sizeof(ctx_new.range.level[0].cat));
3131 }
3132 rc = -EIDRM;
3133 if (!mls_context_isvalid(&policydb, &ctx_new))
3134 goto out_free;
3135
3136 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3137 if (rc)
3138 goto out_free;
3139
3140 security_netlbl_cache_add(secattr, *sid);
3141
3142 ebitmap_destroy(&ctx_new.range.level[0].cat);
3143 } else
3144 *sid = SECSID_NULL;
3145
3146 read_unlock(&policy_rwlock);
3147 return 0;
3148out_free:
3149 ebitmap_destroy(&ctx_new.range.level[0].cat);
3150out:
3151 read_unlock(&policy_rwlock);
3152 return rc;
3153}
3154
3155/**
3156 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3157 * @sid: the SELinux SID
3158 * @secattr: the NetLabel packet security attributes
3159 *
3160 * Description:
3161 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3162 * Returns zero on success, negative values on failure.
3163 *
3164 */
3165int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3166{
3167 int rc;
3168 struct context *ctx;
3169
3170 if (!ss_initialized)
3171 return 0;
3172
3173 read_lock(&policy_rwlock);
3174
3175 rc = -ENOENT;
3176 ctx = sidtab_search(&sidtab, sid);
3177 if (ctx == NULL)
3178 goto out;
3179
3180 rc = -ENOMEM;
3181 secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1),
3182 GFP_ATOMIC);
3183 if (secattr->domain == NULL)
3184 goto out;
3185
3186 secattr->attr.secid = sid;
3187 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3188 mls_export_netlbl_lvl(ctx, secattr);
3189 rc = mls_export_netlbl_cat(ctx, secattr);
3190out:
3191 read_unlock(&policy_rwlock);
3192 return rc;
3193}
3194#endif /* CONFIG_NETLABEL */
3195
3196/**
3197 * security_read_policy - read the policy.
3198 * @data: binary policy data
3199 * @len: length of data in bytes
3200 *
3201 */
3202int security_read_policy(void **data, size_t *len)
3203{
3204 int rc;
3205 struct policy_file fp;
3206
3207 if (!ss_initialized)
3208 return -EINVAL;
3209
3210 *len = security_policydb_len();
3211
3212 *data = vmalloc_user(*len);
3213 if (!*data)
3214 return -ENOMEM;
3215
3216 fp.data = *data;
3217 fp.len = *len;
3218
3219 read_lock(&policy_rwlock);
3220 rc = policydb_write(&policydb, &fp);
3221 read_unlock(&policy_rwlock);
3222
3223 if (rc)
3224 return rc;
3225
3226 *len = (unsigned long)fp.data - (unsigned long)*data;
3227 return 0;
3228
3229}