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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Implementation of the security services.
4 *
5 * Authors : Stephen Smalley, <sds@tycho.nsa.gov>
6 * James Morris <jmorris@redhat.com>
7 *
8 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
9 *
10 * Support for enhanced MLS infrastructure.
11 * Support for context based audit filters.
12 *
13 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
14 *
15 * Added conditional policy language extensions
16 *
17 * Updated: Hewlett-Packard <paul@paul-moore.com>
18 *
19 * Added support for NetLabel
20 * Added support for the policy capability bitmap
21 *
22 * Updated: Chad Sellers <csellers@tresys.com>
23 *
24 * Added validation of kernel classes and permissions
25 *
26 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
27 *
28 * Added support for bounds domain and audit messaged on masked permissions
29 *
30 * Updated: Guido Trentalancia <guido@trentalancia.com>
31 *
32 * Added support for runtime switching of the policy type
33 *
34 * Copyright (C) 2008, 2009 NEC Corporation
35 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
36 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
37 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
38 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
39 */
40#include <linux/kernel.h>
41#include <linux/slab.h>
42#include <linux/string.h>
43#include <linux/spinlock.h>
44#include <linux/rcupdate.h>
45#include <linux/errno.h>
46#include <linux/in.h>
47#include <linux/sched.h>
48#include <linux/audit.h>
49#include <linux/mutex.h>
50#include <linux/vmalloc.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
69/* Policy capability names */
70const char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = {
71 "network_peer_controls",
72 "open_perms",
73 "extended_socket_class",
74 "always_check_network",
75 "cgroup_seclabel",
76 "nnp_nosuid_transition"
77};
78
79static struct selinux_ss selinux_ss;
80
81void selinux_ss_init(struct selinux_ss **ss)
82{
83 rwlock_init(&selinux_ss.policy_rwlock);
84 mutex_init(&selinux_ss.status_lock);
85 *ss = &selinux_ss;
86}
87
88/* Forward declaration. */
89static int context_struct_to_string(struct policydb *policydb,
90 struct context *context,
91 char **scontext,
92 u32 *scontext_len);
93
94static void context_struct_compute_av(struct policydb *policydb,
95 struct context *scontext,
96 struct context *tcontext,
97 u16 tclass,
98 struct av_decision *avd,
99 struct extended_perms *xperms);
100
101static int selinux_set_mapping(struct policydb *pol,
102 struct security_class_mapping *map,
103 struct selinux_map *out_map)
104{
105 u16 i, j;
106 unsigned k;
107 bool print_unknown_handle = false;
108
109 /* Find number of classes in the input mapping */
110 if (!map)
111 return -EINVAL;
112 i = 0;
113 while (map[i].name)
114 i++;
115
116 /* Allocate space for the class records, plus one for class zero */
117 out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC);
118 if (!out_map->mapping)
119 return -ENOMEM;
120
121 /* Store the raw class and permission values */
122 j = 0;
123 while (map[j].name) {
124 struct security_class_mapping *p_in = map + (j++);
125 struct selinux_mapping *p_out = out_map->mapping + j;
126
127 /* An empty class string skips ahead */
128 if (!strcmp(p_in->name, "")) {
129 p_out->num_perms = 0;
130 continue;
131 }
132
133 p_out->value = string_to_security_class(pol, p_in->name);
134 if (!p_out->value) {
135 pr_info("SELinux: Class %s not defined in policy.\n",
136 p_in->name);
137 if (pol->reject_unknown)
138 goto err;
139 p_out->num_perms = 0;
140 print_unknown_handle = true;
141 continue;
142 }
143
144 k = 0;
145 while (p_in->perms[k]) {
146 /* An empty permission string skips ahead */
147 if (!*p_in->perms[k]) {
148 k++;
149 continue;
150 }
151 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
152 p_in->perms[k]);
153 if (!p_out->perms[k]) {
154 pr_info("SELinux: Permission %s in class %s not defined in policy.\n",
155 p_in->perms[k], p_in->name);
156 if (pol->reject_unknown)
157 goto err;
158 print_unknown_handle = true;
159 }
160
161 k++;
162 }
163 p_out->num_perms = k;
164 }
165
166 if (print_unknown_handle)
167 pr_info("SELinux: the above unknown classes and permissions will be %s\n",
168 pol->allow_unknown ? "allowed" : "denied");
169
170 out_map->size = i;
171 return 0;
172err:
173 kfree(out_map->mapping);
174 out_map->mapping = NULL;
175 return -EINVAL;
176}
177
178/*
179 * Get real, policy values from mapped values
180 */
181
182static u16 unmap_class(struct selinux_map *map, u16 tclass)
183{
184 if (tclass < map->size)
185 return map->mapping[tclass].value;
186
187 return tclass;
188}
189
190/*
191 * Get kernel value for class from its policy value
192 */
193static u16 map_class(struct selinux_map *map, u16 pol_value)
194{
195 u16 i;
196
197 for (i = 1; i < map->size; i++) {
198 if (map->mapping[i].value == pol_value)
199 return i;
200 }
201
202 return SECCLASS_NULL;
203}
204
205static void map_decision(struct selinux_map *map,
206 u16 tclass, struct av_decision *avd,
207 int allow_unknown)
208{
209 if (tclass < map->size) {
210 struct selinux_mapping *mapping = &map->mapping[tclass];
211 unsigned int i, n = mapping->num_perms;
212 u32 result;
213
214 for (i = 0, result = 0; i < n; i++) {
215 if (avd->allowed & mapping->perms[i])
216 result |= 1<<i;
217 if (allow_unknown && !mapping->perms[i])
218 result |= 1<<i;
219 }
220 avd->allowed = result;
221
222 for (i = 0, result = 0; i < n; i++)
223 if (avd->auditallow & mapping->perms[i])
224 result |= 1<<i;
225 avd->auditallow = result;
226
227 for (i = 0, result = 0; i < n; i++) {
228 if (avd->auditdeny & mapping->perms[i])
229 result |= 1<<i;
230 if (!allow_unknown && !mapping->perms[i])
231 result |= 1<<i;
232 }
233 /*
234 * In case the kernel has a bug and requests a permission
235 * between num_perms and the maximum permission number, we
236 * should audit that denial
237 */
238 for (; i < (sizeof(u32)*8); i++)
239 result |= 1<<i;
240 avd->auditdeny = result;
241 }
242}
243
244int security_mls_enabled(struct selinux_state *state)
245{
246 struct policydb *p = &state->ss->policydb;
247
248 return p->mls_enabled;
249}
250
251/*
252 * Return the boolean value of a constraint expression
253 * when it is applied to the specified source and target
254 * security contexts.
255 *
256 * xcontext is a special beast... It is used by the validatetrans rules
257 * only. For these rules, scontext is the context before the transition,
258 * tcontext is the context after the transition, and xcontext is the context
259 * of the process performing the transition. All other callers of
260 * constraint_expr_eval should pass in NULL for xcontext.
261 */
262static int constraint_expr_eval(struct policydb *policydb,
263 struct context *scontext,
264 struct context *tcontext,
265 struct context *xcontext,
266 struct constraint_expr *cexpr)
267{
268 u32 val1, val2;
269 struct context *c;
270 struct role_datum *r1, *r2;
271 struct mls_level *l1, *l2;
272 struct constraint_expr *e;
273 int s[CEXPR_MAXDEPTH];
274 int sp = -1;
275
276 for (e = cexpr; e; e = e->next) {
277 switch (e->expr_type) {
278 case CEXPR_NOT:
279 BUG_ON(sp < 0);
280 s[sp] = !s[sp];
281 break;
282 case CEXPR_AND:
283 BUG_ON(sp < 1);
284 sp--;
285 s[sp] &= s[sp + 1];
286 break;
287 case CEXPR_OR:
288 BUG_ON(sp < 1);
289 sp--;
290 s[sp] |= s[sp + 1];
291 break;
292 case CEXPR_ATTR:
293 if (sp == (CEXPR_MAXDEPTH - 1))
294 return 0;
295 switch (e->attr) {
296 case CEXPR_USER:
297 val1 = scontext->user;
298 val2 = tcontext->user;
299 break;
300 case CEXPR_TYPE:
301 val1 = scontext->type;
302 val2 = tcontext->type;
303 break;
304 case CEXPR_ROLE:
305 val1 = scontext->role;
306 val2 = tcontext->role;
307 r1 = policydb->role_val_to_struct[val1 - 1];
308 r2 = policydb->role_val_to_struct[val2 - 1];
309 switch (e->op) {
310 case CEXPR_DOM:
311 s[++sp] = ebitmap_get_bit(&r1->dominates,
312 val2 - 1);
313 continue;
314 case CEXPR_DOMBY:
315 s[++sp] = ebitmap_get_bit(&r2->dominates,
316 val1 - 1);
317 continue;
318 case CEXPR_INCOMP:
319 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
320 val2 - 1) &&
321 !ebitmap_get_bit(&r2->dominates,
322 val1 - 1));
323 continue;
324 default:
325 break;
326 }
327 break;
328 case CEXPR_L1L2:
329 l1 = &(scontext->range.level[0]);
330 l2 = &(tcontext->range.level[0]);
331 goto mls_ops;
332 case CEXPR_L1H2:
333 l1 = &(scontext->range.level[0]);
334 l2 = &(tcontext->range.level[1]);
335 goto mls_ops;
336 case CEXPR_H1L2:
337 l1 = &(scontext->range.level[1]);
338 l2 = &(tcontext->range.level[0]);
339 goto mls_ops;
340 case CEXPR_H1H2:
341 l1 = &(scontext->range.level[1]);
342 l2 = &(tcontext->range.level[1]);
343 goto mls_ops;
344 case CEXPR_L1H1:
345 l1 = &(scontext->range.level[0]);
346 l2 = &(scontext->range.level[1]);
347 goto mls_ops;
348 case CEXPR_L2H2:
349 l1 = &(tcontext->range.level[0]);
350 l2 = &(tcontext->range.level[1]);
351 goto mls_ops;
352mls_ops:
353 switch (e->op) {
354 case CEXPR_EQ:
355 s[++sp] = mls_level_eq(l1, l2);
356 continue;
357 case CEXPR_NEQ:
358 s[++sp] = !mls_level_eq(l1, l2);
359 continue;
360 case CEXPR_DOM:
361 s[++sp] = mls_level_dom(l1, l2);
362 continue;
363 case CEXPR_DOMBY:
364 s[++sp] = mls_level_dom(l2, l1);
365 continue;
366 case CEXPR_INCOMP:
367 s[++sp] = mls_level_incomp(l2, l1);
368 continue;
369 default:
370 BUG();
371 return 0;
372 }
373 break;
374 default:
375 BUG();
376 return 0;
377 }
378
379 switch (e->op) {
380 case CEXPR_EQ:
381 s[++sp] = (val1 == val2);
382 break;
383 case CEXPR_NEQ:
384 s[++sp] = (val1 != val2);
385 break;
386 default:
387 BUG();
388 return 0;
389 }
390 break;
391 case CEXPR_NAMES:
392 if (sp == (CEXPR_MAXDEPTH-1))
393 return 0;
394 c = scontext;
395 if (e->attr & CEXPR_TARGET)
396 c = tcontext;
397 else if (e->attr & CEXPR_XTARGET) {
398 c = xcontext;
399 if (!c) {
400 BUG();
401 return 0;
402 }
403 }
404 if (e->attr & CEXPR_USER)
405 val1 = c->user;
406 else if (e->attr & CEXPR_ROLE)
407 val1 = c->role;
408 else if (e->attr & CEXPR_TYPE)
409 val1 = c->type;
410 else {
411 BUG();
412 return 0;
413 }
414
415 switch (e->op) {
416 case CEXPR_EQ:
417 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
418 break;
419 case CEXPR_NEQ:
420 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
421 break;
422 default:
423 BUG();
424 return 0;
425 }
426 break;
427 default:
428 BUG();
429 return 0;
430 }
431 }
432
433 BUG_ON(sp != 0);
434 return s[0];
435}
436
437/*
438 * security_dump_masked_av - dumps masked permissions during
439 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
440 */
441static int dump_masked_av_helper(void *k, void *d, void *args)
442{
443 struct perm_datum *pdatum = d;
444 char **permission_names = args;
445
446 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
447
448 permission_names[pdatum->value - 1] = (char *)k;
449
450 return 0;
451}
452
453static void security_dump_masked_av(struct policydb *policydb,
454 struct context *scontext,
455 struct context *tcontext,
456 u16 tclass,
457 u32 permissions,
458 const char *reason)
459{
460 struct common_datum *common_dat;
461 struct class_datum *tclass_dat;
462 struct audit_buffer *ab;
463 char *tclass_name;
464 char *scontext_name = NULL;
465 char *tcontext_name = NULL;
466 char *permission_names[32];
467 int index;
468 u32 length;
469 bool need_comma = false;
470
471 if (!permissions)
472 return;
473
474 tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1);
475 tclass_dat = policydb->class_val_to_struct[tclass - 1];
476 common_dat = tclass_dat->comdatum;
477
478 /* init permission_names */
479 if (common_dat &&
480 hashtab_map(common_dat->permissions.table,
481 dump_masked_av_helper, permission_names) < 0)
482 goto out;
483
484 if (hashtab_map(tclass_dat->permissions.table,
485 dump_masked_av_helper, permission_names) < 0)
486 goto out;
487
488 /* get scontext/tcontext in text form */
489 if (context_struct_to_string(policydb, scontext,
490 &scontext_name, &length) < 0)
491 goto out;
492
493 if (context_struct_to_string(policydb, tcontext,
494 &tcontext_name, &length) < 0)
495 goto out;
496
497 /* audit a message */
498 ab = audit_log_start(audit_context(),
499 GFP_ATOMIC, AUDIT_SELINUX_ERR);
500 if (!ab)
501 goto out;
502
503 audit_log_format(ab, "op=security_compute_av reason=%s "
504 "scontext=%s tcontext=%s tclass=%s perms=",
505 reason, scontext_name, tcontext_name, tclass_name);
506
507 for (index = 0; index < 32; index++) {
508 u32 mask = (1 << index);
509
510 if ((mask & permissions) == 0)
511 continue;
512
513 audit_log_format(ab, "%s%s",
514 need_comma ? "," : "",
515 permission_names[index]
516 ? permission_names[index] : "????");
517 need_comma = true;
518 }
519 audit_log_end(ab);
520out:
521 /* release scontext/tcontext */
522 kfree(tcontext_name);
523 kfree(scontext_name);
524
525 return;
526}
527
528/*
529 * security_boundary_permission - drops violated permissions
530 * on boundary constraint.
531 */
532static void type_attribute_bounds_av(struct policydb *policydb,
533 struct context *scontext,
534 struct context *tcontext,
535 u16 tclass,
536 struct av_decision *avd)
537{
538 struct context lo_scontext;
539 struct context lo_tcontext, *tcontextp = tcontext;
540 struct av_decision lo_avd;
541 struct type_datum *source;
542 struct type_datum *target;
543 u32 masked = 0;
544
545 source = policydb->type_val_to_struct[scontext->type - 1];
546 BUG_ON(!source);
547
548 if (!source->bounds)
549 return;
550
551 target = policydb->type_val_to_struct[tcontext->type - 1];
552 BUG_ON(!target);
553
554 memset(&lo_avd, 0, sizeof(lo_avd));
555
556 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
557 lo_scontext.type = source->bounds;
558
559 if (target->bounds) {
560 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
561 lo_tcontext.type = target->bounds;
562 tcontextp = &lo_tcontext;
563 }
564
565 context_struct_compute_av(policydb, &lo_scontext,
566 tcontextp,
567 tclass,
568 &lo_avd,
569 NULL);
570
571 masked = ~lo_avd.allowed & avd->allowed;
572
573 if (likely(!masked))
574 return; /* no masked permission */
575
576 /* mask violated permissions */
577 avd->allowed &= ~masked;
578
579 /* audit masked permissions */
580 security_dump_masked_av(policydb, scontext, tcontext,
581 tclass, masked, "bounds");
582}
583
584/*
585 * flag which drivers have permissions
586 * only looking for ioctl based extended permssions
587 */
588void services_compute_xperms_drivers(
589 struct extended_perms *xperms,
590 struct avtab_node *node)
591{
592 unsigned int i;
593
594 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
595 /* if one or more driver has all permissions allowed */
596 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
597 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
598 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
599 /* if allowing permissions within a driver */
600 security_xperm_set(xperms->drivers.p,
601 node->datum.u.xperms->driver);
602 }
603
604 /* If no ioctl commands are allowed, ignore auditallow and auditdeny */
605 if (node->key.specified & AVTAB_XPERMS_ALLOWED)
606 xperms->len = 1;
607}
608
609/*
610 * Compute access vectors and extended permissions based on a context
611 * structure pair for the permissions in a particular class.
612 */
613static void context_struct_compute_av(struct policydb *policydb,
614 struct context *scontext,
615 struct context *tcontext,
616 u16 tclass,
617 struct av_decision *avd,
618 struct extended_perms *xperms)
619{
620 struct constraint_node *constraint;
621 struct role_allow *ra;
622 struct avtab_key avkey;
623 struct avtab_node *node;
624 struct class_datum *tclass_datum;
625 struct ebitmap *sattr, *tattr;
626 struct ebitmap_node *snode, *tnode;
627 unsigned int i, j;
628
629 avd->allowed = 0;
630 avd->auditallow = 0;
631 avd->auditdeny = 0xffffffff;
632 if (xperms) {
633 memset(&xperms->drivers, 0, sizeof(xperms->drivers));
634 xperms->len = 0;
635 }
636
637 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
638 if (printk_ratelimit())
639 pr_warn("SELinux: Invalid class %hu\n", tclass);
640 return;
641 }
642
643 tclass_datum = policydb->class_val_to_struct[tclass - 1];
644
645 /*
646 * If a specific type enforcement rule was defined for
647 * this permission check, then use it.
648 */
649 avkey.target_class = tclass;
650 avkey.specified = AVTAB_AV | AVTAB_XPERMS;
651 sattr = &policydb->type_attr_map_array[scontext->type - 1];
652 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
653 ebitmap_for_each_positive_bit(sattr, snode, i) {
654 ebitmap_for_each_positive_bit(tattr, tnode, j) {
655 avkey.source_type = i + 1;
656 avkey.target_type = j + 1;
657 for (node = avtab_search_node(&policydb->te_avtab,
658 &avkey);
659 node;
660 node = avtab_search_node_next(node, avkey.specified)) {
661 if (node->key.specified == AVTAB_ALLOWED)
662 avd->allowed |= node->datum.u.data;
663 else if (node->key.specified == AVTAB_AUDITALLOW)
664 avd->auditallow |= node->datum.u.data;
665 else if (node->key.specified == AVTAB_AUDITDENY)
666 avd->auditdeny &= node->datum.u.data;
667 else if (xperms && (node->key.specified & AVTAB_XPERMS))
668 services_compute_xperms_drivers(xperms, node);
669 }
670
671 /* Check conditional av table for additional permissions */
672 cond_compute_av(&policydb->te_cond_avtab, &avkey,
673 avd, xperms);
674
675 }
676 }
677
678 /*
679 * Remove any permissions prohibited by a constraint (this includes
680 * the MLS policy).
681 */
682 constraint = tclass_datum->constraints;
683 while (constraint) {
684 if ((constraint->permissions & (avd->allowed)) &&
685 !constraint_expr_eval(policydb, scontext, tcontext, NULL,
686 constraint->expr)) {
687 avd->allowed &= ~(constraint->permissions);
688 }
689 constraint = constraint->next;
690 }
691
692 /*
693 * If checking process transition permission and the
694 * role is changing, then check the (current_role, new_role)
695 * pair.
696 */
697 if (tclass == policydb->process_class &&
698 (avd->allowed & policydb->process_trans_perms) &&
699 scontext->role != tcontext->role) {
700 for (ra = policydb->role_allow; ra; ra = ra->next) {
701 if (scontext->role == ra->role &&
702 tcontext->role == ra->new_role)
703 break;
704 }
705 if (!ra)
706 avd->allowed &= ~policydb->process_trans_perms;
707 }
708
709 /*
710 * If the given source and target types have boundary
711 * constraint, lazy checks have to mask any violated
712 * permission and notice it to userspace via audit.
713 */
714 type_attribute_bounds_av(policydb, scontext, tcontext,
715 tclass, avd);
716}
717
718static int security_validtrans_handle_fail(struct selinux_state *state,
719 struct context *ocontext,
720 struct context *ncontext,
721 struct context *tcontext,
722 u16 tclass)
723{
724 struct policydb *p = &state->ss->policydb;
725 char *o = NULL, *n = NULL, *t = NULL;
726 u32 olen, nlen, tlen;
727
728 if (context_struct_to_string(p, ocontext, &o, &olen))
729 goto out;
730 if (context_struct_to_string(p, ncontext, &n, &nlen))
731 goto out;
732 if (context_struct_to_string(p, tcontext, &t, &tlen))
733 goto out;
734 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
735 "op=security_validate_transition seresult=denied"
736 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
737 o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
738out:
739 kfree(o);
740 kfree(n);
741 kfree(t);
742
743 if (!enforcing_enabled(state))
744 return 0;
745 return -EPERM;
746}
747
748static int security_compute_validatetrans(struct selinux_state *state,
749 u32 oldsid, u32 newsid, u32 tasksid,
750 u16 orig_tclass, bool user)
751{
752 struct policydb *policydb;
753 struct sidtab *sidtab;
754 struct context *ocontext;
755 struct context *ncontext;
756 struct context *tcontext;
757 struct class_datum *tclass_datum;
758 struct constraint_node *constraint;
759 u16 tclass;
760 int rc = 0;
761
762
763 if (!state->initialized)
764 return 0;
765
766 read_lock(&state->ss->policy_rwlock);
767
768 policydb = &state->ss->policydb;
769 sidtab = state->ss->sidtab;
770
771 if (!user)
772 tclass = unmap_class(&state->ss->map, orig_tclass);
773 else
774 tclass = orig_tclass;
775
776 if (!tclass || tclass > policydb->p_classes.nprim) {
777 rc = -EINVAL;
778 goto out;
779 }
780 tclass_datum = policydb->class_val_to_struct[tclass - 1];
781
782 ocontext = sidtab_search(sidtab, oldsid);
783 if (!ocontext) {
784 pr_err("SELinux: %s: unrecognized SID %d\n",
785 __func__, oldsid);
786 rc = -EINVAL;
787 goto out;
788 }
789
790 ncontext = sidtab_search(sidtab, newsid);
791 if (!ncontext) {
792 pr_err("SELinux: %s: unrecognized SID %d\n",
793 __func__, newsid);
794 rc = -EINVAL;
795 goto out;
796 }
797
798 tcontext = sidtab_search(sidtab, tasksid);
799 if (!tcontext) {
800 pr_err("SELinux: %s: unrecognized SID %d\n",
801 __func__, tasksid);
802 rc = -EINVAL;
803 goto out;
804 }
805
806 constraint = tclass_datum->validatetrans;
807 while (constraint) {
808 if (!constraint_expr_eval(policydb, ocontext, ncontext,
809 tcontext, constraint->expr)) {
810 if (user)
811 rc = -EPERM;
812 else
813 rc = security_validtrans_handle_fail(state,
814 ocontext,
815 ncontext,
816 tcontext,
817 tclass);
818 goto out;
819 }
820 constraint = constraint->next;
821 }
822
823out:
824 read_unlock(&state->ss->policy_rwlock);
825 return rc;
826}
827
828int security_validate_transition_user(struct selinux_state *state,
829 u32 oldsid, u32 newsid, u32 tasksid,
830 u16 tclass)
831{
832 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
833 tclass, true);
834}
835
836int security_validate_transition(struct selinux_state *state,
837 u32 oldsid, u32 newsid, u32 tasksid,
838 u16 orig_tclass)
839{
840 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
841 orig_tclass, false);
842}
843
844/*
845 * security_bounded_transition - check whether the given
846 * transition is directed to bounded, or not.
847 * It returns 0, if @newsid is bounded by @oldsid.
848 * Otherwise, it returns error code.
849 *
850 * @oldsid : current security identifier
851 * @newsid : destinated security identifier
852 */
853int security_bounded_transition(struct selinux_state *state,
854 u32 old_sid, u32 new_sid)
855{
856 struct policydb *policydb;
857 struct sidtab *sidtab;
858 struct context *old_context, *new_context;
859 struct type_datum *type;
860 int index;
861 int rc;
862
863 if (!state->initialized)
864 return 0;
865
866 read_lock(&state->ss->policy_rwlock);
867
868 policydb = &state->ss->policydb;
869 sidtab = state->ss->sidtab;
870
871 rc = -EINVAL;
872 old_context = sidtab_search(sidtab, old_sid);
873 if (!old_context) {
874 pr_err("SELinux: %s: unrecognized SID %u\n",
875 __func__, old_sid);
876 goto out;
877 }
878
879 rc = -EINVAL;
880 new_context = sidtab_search(sidtab, new_sid);
881 if (!new_context) {
882 pr_err("SELinux: %s: unrecognized SID %u\n",
883 __func__, new_sid);
884 goto out;
885 }
886
887 rc = 0;
888 /* type/domain unchanged */
889 if (old_context->type == new_context->type)
890 goto out;
891
892 index = new_context->type;
893 while (true) {
894 type = policydb->type_val_to_struct[index - 1];
895 BUG_ON(!type);
896
897 /* not bounded anymore */
898 rc = -EPERM;
899 if (!type->bounds)
900 break;
901
902 /* @newsid is bounded by @oldsid */
903 rc = 0;
904 if (type->bounds == old_context->type)
905 break;
906
907 index = type->bounds;
908 }
909
910 if (rc) {
911 char *old_name = NULL;
912 char *new_name = NULL;
913 u32 length;
914
915 if (!context_struct_to_string(policydb, old_context,
916 &old_name, &length) &&
917 !context_struct_to_string(policydb, new_context,
918 &new_name, &length)) {
919 audit_log(audit_context(),
920 GFP_ATOMIC, AUDIT_SELINUX_ERR,
921 "op=security_bounded_transition "
922 "seresult=denied "
923 "oldcontext=%s newcontext=%s",
924 old_name, new_name);
925 }
926 kfree(new_name);
927 kfree(old_name);
928 }
929out:
930 read_unlock(&state->ss->policy_rwlock);
931
932 return rc;
933}
934
935static void avd_init(struct selinux_state *state, struct av_decision *avd)
936{
937 avd->allowed = 0;
938 avd->auditallow = 0;
939 avd->auditdeny = 0xffffffff;
940 avd->seqno = state->ss->latest_granting;
941 avd->flags = 0;
942}
943
944void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
945 struct avtab_node *node)
946{
947 unsigned int i;
948
949 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
950 if (xpermd->driver != node->datum.u.xperms->driver)
951 return;
952 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
953 if (!security_xperm_test(node->datum.u.xperms->perms.p,
954 xpermd->driver))
955 return;
956 } else {
957 BUG();
958 }
959
960 if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
961 xpermd->used |= XPERMS_ALLOWED;
962 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
963 memset(xpermd->allowed->p, 0xff,
964 sizeof(xpermd->allowed->p));
965 }
966 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
967 for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++)
968 xpermd->allowed->p[i] |=
969 node->datum.u.xperms->perms.p[i];
970 }
971 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
972 xpermd->used |= XPERMS_AUDITALLOW;
973 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
974 memset(xpermd->auditallow->p, 0xff,
975 sizeof(xpermd->auditallow->p));
976 }
977 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
978 for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++)
979 xpermd->auditallow->p[i] |=
980 node->datum.u.xperms->perms.p[i];
981 }
982 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
983 xpermd->used |= XPERMS_DONTAUDIT;
984 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
985 memset(xpermd->dontaudit->p, 0xff,
986 sizeof(xpermd->dontaudit->p));
987 }
988 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
989 for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++)
990 xpermd->dontaudit->p[i] |=
991 node->datum.u.xperms->perms.p[i];
992 }
993 } else {
994 BUG();
995 }
996}
997
998void security_compute_xperms_decision(struct selinux_state *state,
999 u32 ssid,
1000 u32 tsid,
1001 u16 orig_tclass,
1002 u8 driver,
1003 struct extended_perms_decision *xpermd)
1004{
1005 struct policydb *policydb;
1006 struct sidtab *sidtab;
1007 u16 tclass;
1008 struct context *scontext, *tcontext;
1009 struct avtab_key avkey;
1010 struct avtab_node *node;
1011 struct ebitmap *sattr, *tattr;
1012 struct ebitmap_node *snode, *tnode;
1013 unsigned int i, j;
1014
1015 xpermd->driver = driver;
1016 xpermd->used = 0;
1017 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1018 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1019 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1020
1021 read_lock(&state->ss->policy_rwlock);
1022 if (!state->initialized)
1023 goto allow;
1024
1025 policydb = &state->ss->policydb;
1026 sidtab = state->ss->sidtab;
1027
1028 scontext = sidtab_search(sidtab, ssid);
1029 if (!scontext) {
1030 pr_err("SELinux: %s: unrecognized SID %d\n",
1031 __func__, ssid);
1032 goto out;
1033 }
1034
1035 tcontext = sidtab_search(sidtab, tsid);
1036 if (!tcontext) {
1037 pr_err("SELinux: %s: unrecognized SID %d\n",
1038 __func__, tsid);
1039 goto out;
1040 }
1041
1042 tclass = unmap_class(&state->ss->map, orig_tclass);
1043 if (unlikely(orig_tclass && !tclass)) {
1044 if (policydb->allow_unknown)
1045 goto allow;
1046 goto out;
1047 }
1048
1049
1050 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1051 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1052 goto out;
1053 }
1054
1055 avkey.target_class = tclass;
1056 avkey.specified = AVTAB_XPERMS;
1057 sattr = &policydb->type_attr_map_array[scontext->type - 1];
1058 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
1059 ebitmap_for_each_positive_bit(sattr, snode, i) {
1060 ebitmap_for_each_positive_bit(tattr, tnode, j) {
1061 avkey.source_type = i + 1;
1062 avkey.target_type = j + 1;
1063 for (node = avtab_search_node(&policydb->te_avtab,
1064 &avkey);
1065 node;
1066 node = avtab_search_node_next(node, avkey.specified))
1067 services_compute_xperms_decision(xpermd, node);
1068
1069 cond_compute_xperms(&policydb->te_cond_avtab,
1070 &avkey, xpermd);
1071 }
1072 }
1073out:
1074 read_unlock(&state->ss->policy_rwlock);
1075 return;
1076allow:
1077 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1078 goto out;
1079}
1080
1081/**
1082 * security_compute_av - Compute access vector decisions.
1083 * @ssid: source security identifier
1084 * @tsid: target security identifier
1085 * @tclass: target security class
1086 * @avd: access vector decisions
1087 * @xperms: extended permissions
1088 *
1089 * Compute a set of access vector decisions based on the
1090 * SID pair (@ssid, @tsid) for the permissions in @tclass.
1091 */
1092void security_compute_av(struct selinux_state *state,
1093 u32 ssid,
1094 u32 tsid,
1095 u16 orig_tclass,
1096 struct av_decision *avd,
1097 struct extended_perms *xperms)
1098{
1099 struct policydb *policydb;
1100 struct sidtab *sidtab;
1101 u16 tclass;
1102 struct context *scontext = NULL, *tcontext = NULL;
1103
1104 read_lock(&state->ss->policy_rwlock);
1105 avd_init(state, avd);
1106 xperms->len = 0;
1107 if (!state->initialized)
1108 goto allow;
1109
1110 policydb = &state->ss->policydb;
1111 sidtab = state->ss->sidtab;
1112
1113 scontext = sidtab_search(sidtab, ssid);
1114 if (!scontext) {
1115 pr_err("SELinux: %s: unrecognized SID %d\n",
1116 __func__, ssid);
1117 goto out;
1118 }
1119
1120 /* permissive domain? */
1121 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1122 avd->flags |= AVD_FLAGS_PERMISSIVE;
1123
1124 tcontext = sidtab_search(sidtab, tsid);
1125 if (!tcontext) {
1126 pr_err("SELinux: %s: unrecognized SID %d\n",
1127 __func__, tsid);
1128 goto out;
1129 }
1130
1131 tclass = unmap_class(&state->ss->map, orig_tclass);
1132 if (unlikely(orig_tclass && !tclass)) {
1133 if (policydb->allow_unknown)
1134 goto allow;
1135 goto out;
1136 }
1137 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1138 xperms);
1139 map_decision(&state->ss->map, orig_tclass, avd,
1140 policydb->allow_unknown);
1141out:
1142 read_unlock(&state->ss->policy_rwlock);
1143 return;
1144allow:
1145 avd->allowed = 0xffffffff;
1146 goto out;
1147}
1148
1149void security_compute_av_user(struct selinux_state *state,
1150 u32 ssid,
1151 u32 tsid,
1152 u16 tclass,
1153 struct av_decision *avd)
1154{
1155 struct policydb *policydb;
1156 struct sidtab *sidtab;
1157 struct context *scontext = NULL, *tcontext = NULL;
1158
1159 read_lock(&state->ss->policy_rwlock);
1160 avd_init(state, avd);
1161 if (!state->initialized)
1162 goto allow;
1163
1164 policydb = &state->ss->policydb;
1165 sidtab = state->ss->sidtab;
1166
1167 scontext = sidtab_search(sidtab, ssid);
1168 if (!scontext) {
1169 pr_err("SELinux: %s: unrecognized SID %d\n",
1170 __func__, ssid);
1171 goto out;
1172 }
1173
1174 /* permissive domain? */
1175 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1176 avd->flags |= AVD_FLAGS_PERMISSIVE;
1177
1178 tcontext = sidtab_search(sidtab, tsid);
1179 if (!tcontext) {
1180 pr_err("SELinux: %s: unrecognized SID %d\n",
1181 __func__, tsid);
1182 goto out;
1183 }
1184
1185 if (unlikely(!tclass)) {
1186 if (policydb->allow_unknown)
1187 goto allow;
1188 goto out;
1189 }
1190
1191 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1192 NULL);
1193 out:
1194 read_unlock(&state->ss->policy_rwlock);
1195 return;
1196allow:
1197 avd->allowed = 0xffffffff;
1198 goto out;
1199}
1200
1201/*
1202 * Write the security context string representation of
1203 * the context structure `context' into a dynamically
1204 * allocated string of the correct size. Set `*scontext'
1205 * to point to this string and set `*scontext_len' to
1206 * the length of the string.
1207 */
1208static int context_struct_to_string(struct policydb *p,
1209 struct context *context,
1210 char **scontext, u32 *scontext_len)
1211{
1212 char *scontextp;
1213
1214 if (scontext)
1215 *scontext = NULL;
1216 *scontext_len = 0;
1217
1218 if (context->len) {
1219 *scontext_len = context->len;
1220 if (scontext) {
1221 *scontext = kstrdup(context->str, GFP_ATOMIC);
1222 if (!(*scontext))
1223 return -ENOMEM;
1224 }
1225 return 0;
1226 }
1227
1228 /* Compute the size of the context. */
1229 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1230 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1231 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1232 *scontext_len += mls_compute_context_len(p, context);
1233
1234 if (!scontext)
1235 return 0;
1236
1237 /* Allocate space for the context; caller must free this space. */
1238 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1239 if (!scontextp)
1240 return -ENOMEM;
1241 *scontext = scontextp;
1242
1243 /*
1244 * Copy the user name, role name and type name into the context.
1245 */
1246 scontextp += sprintf(scontextp, "%s:%s:%s",
1247 sym_name(p, SYM_USERS, context->user - 1),
1248 sym_name(p, SYM_ROLES, context->role - 1),
1249 sym_name(p, SYM_TYPES, context->type - 1));
1250
1251 mls_sid_to_context(p, context, &scontextp);
1252
1253 *scontextp = 0;
1254
1255 return 0;
1256}
1257
1258#include "initial_sid_to_string.h"
1259
1260const char *security_get_initial_sid_context(u32 sid)
1261{
1262 if (unlikely(sid > SECINITSID_NUM))
1263 return NULL;
1264 return initial_sid_to_string[sid];
1265}
1266
1267static int security_sid_to_context_core(struct selinux_state *state,
1268 u32 sid, char **scontext,
1269 u32 *scontext_len, int force,
1270 int only_invalid)
1271{
1272 struct policydb *policydb;
1273 struct sidtab *sidtab;
1274 struct context *context;
1275 int rc = 0;
1276
1277 if (scontext)
1278 *scontext = NULL;
1279 *scontext_len = 0;
1280
1281 if (!state->initialized) {
1282 if (sid <= SECINITSID_NUM) {
1283 char *scontextp;
1284
1285 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1286 if (!scontext)
1287 goto out;
1288 scontextp = kmemdup(initial_sid_to_string[sid],
1289 *scontext_len, GFP_ATOMIC);
1290 if (!scontextp) {
1291 rc = -ENOMEM;
1292 goto out;
1293 }
1294 *scontext = scontextp;
1295 goto out;
1296 }
1297 pr_err("SELinux: %s: called before initial "
1298 "load_policy on unknown SID %d\n", __func__, sid);
1299 rc = -EINVAL;
1300 goto out;
1301 }
1302 read_lock(&state->ss->policy_rwlock);
1303 policydb = &state->ss->policydb;
1304 sidtab = state->ss->sidtab;
1305 if (force)
1306 context = sidtab_search_force(sidtab, sid);
1307 else
1308 context = sidtab_search(sidtab, sid);
1309 if (!context) {
1310 pr_err("SELinux: %s: unrecognized SID %d\n",
1311 __func__, sid);
1312 rc = -EINVAL;
1313 goto out_unlock;
1314 }
1315 if (only_invalid && !context->len)
1316 rc = 0;
1317 else
1318 rc = context_struct_to_string(policydb, context, scontext,
1319 scontext_len);
1320out_unlock:
1321 read_unlock(&state->ss->policy_rwlock);
1322out:
1323 return rc;
1324
1325}
1326
1327/**
1328 * security_sid_to_context - Obtain a context for a given SID.
1329 * @sid: security identifier, SID
1330 * @scontext: security context
1331 * @scontext_len: length in bytes
1332 *
1333 * Write the string representation of the context associated with @sid
1334 * into a dynamically allocated string of the correct size. Set @scontext
1335 * to point to this string and set @scontext_len to the length of the string.
1336 */
1337int security_sid_to_context(struct selinux_state *state,
1338 u32 sid, char **scontext, u32 *scontext_len)
1339{
1340 return security_sid_to_context_core(state, sid, scontext,
1341 scontext_len, 0, 0);
1342}
1343
1344int security_sid_to_context_force(struct selinux_state *state, u32 sid,
1345 char **scontext, u32 *scontext_len)
1346{
1347 return security_sid_to_context_core(state, sid, scontext,
1348 scontext_len, 1, 0);
1349}
1350
1351/**
1352 * security_sid_to_context_inval - Obtain a context for a given SID if it
1353 * is invalid.
1354 * @sid: security identifier, SID
1355 * @scontext: security context
1356 * @scontext_len: length in bytes
1357 *
1358 * Write the string representation of the context associated with @sid
1359 * into a dynamically allocated string of the correct size, but only if the
1360 * context is invalid in the current policy. Set @scontext to point to
1361 * this string (or NULL if the context is valid) and set @scontext_len to
1362 * the length of the string (or 0 if the context is valid).
1363 */
1364int security_sid_to_context_inval(struct selinux_state *state, u32 sid,
1365 char **scontext, u32 *scontext_len)
1366{
1367 return security_sid_to_context_core(state, sid, scontext,
1368 scontext_len, 1, 1);
1369}
1370
1371/*
1372 * Caveat: Mutates scontext.
1373 */
1374static int string_to_context_struct(struct policydb *pol,
1375 struct sidtab *sidtabp,
1376 char *scontext,
1377 struct context *ctx,
1378 u32 def_sid)
1379{
1380 struct role_datum *role;
1381 struct type_datum *typdatum;
1382 struct user_datum *usrdatum;
1383 char *scontextp, *p, oldc;
1384 int rc = 0;
1385
1386 context_init(ctx);
1387
1388 /* Parse the security context. */
1389
1390 rc = -EINVAL;
1391 scontextp = (char *) scontext;
1392
1393 /* Extract the user. */
1394 p = scontextp;
1395 while (*p && *p != ':')
1396 p++;
1397
1398 if (*p == 0)
1399 goto out;
1400
1401 *p++ = 0;
1402
1403 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1404 if (!usrdatum)
1405 goto out;
1406
1407 ctx->user = usrdatum->value;
1408
1409 /* Extract role. */
1410 scontextp = p;
1411 while (*p && *p != ':')
1412 p++;
1413
1414 if (*p == 0)
1415 goto out;
1416
1417 *p++ = 0;
1418
1419 role = hashtab_search(pol->p_roles.table, scontextp);
1420 if (!role)
1421 goto out;
1422 ctx->role = role->value;
1423
1424 /* Extract type. */
1425 scontextp = p;
1426 while (*p && *p != ':')
1427 p++;
1428 oldc = *p;
1429 *p++ = 0;
1430
1431 typdatum = hashtab_search(pol->p_types.table, scontextp);
1432 if (!typdatum || typdatum->attribute)
1433 goto out;
1434
1435 ctx->type = typdatum->value;
1436
1437 rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid);
1438 if (rc)
1439 goto out;
1440
1441 /* Check the validity of the new context. */
1442 rc = -EINVAL;
1443 if (!policydb_context_isvalid(pol, ctx))
1444 goto out;
1445 rc = 0;
1446out:
1447 if (rc)
1448 context_destroy(ctx);
1449 return rc;
1450}
1451
1452static int security_context_to_sid_core(struct selinux_state *state,
1453 const char *scontext, u32 scontext_len,
1454 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1455 int force)
1456{
1457 struct policydb *policydb;
1458 struct sidtab *sidtab;
1459 char *scontext2, *str = NULL;
1460 struct context context;
1461 int rc = 0;
1462
1463 /* An empty security context is never valid. */
1464 if (!scontext_len)
1465 return -EINVAL;
1466
1467 /* Copy the string to allow changes and ensure a NUL terminator */
1468 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags);
1469 if (!scontext2)
1470 return -ENOMEM;
1471
1472 if (!state->initialized) {
1473 int i;
1474
1475 for (i = 1; i < SECINITSID_NUM; i++) {
1476 if (!strcmp(initial_sid_to_string[i], scontext2)) {
1477 *sid = i;
1478 goto out;
1479 }
1480 }
1481 *sid = SECINITSID_KERNEL;
1482 goto out;
1483 }
1484 *sid = SECSID_NULL;
1485
1486 if (force) {
1487 /* Save another copy for storing in uninterpreted form */
1488 rc = -ENOMEM;
1489 str = kstrdup(scontext2, gfp_flags);
1490 if (!str)
1491 goto out;
1492 }
1493 read_lock(&state->ss->policy_rwlock);
1494 policydb = &state->ss->policydb;
1495 sidtab = state->ss->sidtab;
1496 rc = string_to_context_struct(policydb, sidtab, scontext2,
1497 &context, def_sid);
1498 if (rc == -EINVAL && force) {
1499 context.str = str;
1500 context.len = strlen(str) + 1;
1501 str = NULL;
1502 } else if (rc)
1503 goto out_unlock;
1504 rc = sidtab_context_to_sid(sidtab, &context, sid);
1505 context_destroy(&context);
1506out_unlock:
1507 read_unlock(&state->ss->policy_rwlock);
1508out:
1509 kfree(scontext2);
1510 kfree(str);
1511 return rc;
1512}
1513
1514/**
1515 * security_context_to_sid - Obtain a SID for a given security context.
1516 * @scontext: security context
1517 * @scontext_len: length in bytes
1518 * @sid: security identifier, SID
1519 * @gfp: context for the allocation
1520 *
1521 * Obtains a SID associated with the security context that
1522 * has the string representation specified by @scontext.
1523 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1524 * memory is available, or 0 on success.
1525 */
1526int security_context_to_sid(struct selinux_state *state,
1527 const char *scontext, u32 scontext_len, u32 *sid,
1528 gfp_t gfp)
1529{
1530 return security_context_to_sid_core(state, scontext, scontext_len,
1531 sid, SECSID_NULL, gfp, 0);
1532}
1533
1534int security_context_str_to_sid(struct selinux_state *state,
1535 const char *scontext, u32 *sid, gfp_t gfp)
1536{
1537 return security_context_to_sid(state, scontext, strlen(scontext),
1538 sid, gfp);
1539}
1540
1541/**
1542 * security_context_to_sid_default - Obtain a SID for a given security context,
1543 * falling back to specified default if needed.
1544 *
1545 * @scontext: security context
1546 * @scontext_len: length in bytes
1547 * @sid: security identifier, SID
1548 * @def_sid: default SID to assign on error
1549 *
1550 * Obtains a SID associated with the security context that
1551 * has the string representation specified by @scontext.
1552 * The default SID is passed to the MLS layer to be used to allow
1553 * kernel labeling of the MLS field if the MLS field is not present
1554 * (for upgrading to MLS without full relabel).
1555 * Implicitly forces adding of the context even if it cannot be mapped yet.
1556 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1557 * memory is available, or 0 on success.
1558 */
1559int security_context_to_sid_default(struct selinux_state *state,
1560 const char *scontext, u32 scontext_len,
1561 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1562{
1563 return security_context_to_sid_core(state, scontext, scontext_len,
1564 sid, def_sid, gfp_flags, 1);
1565}
1566
1567int security_context_to_sid_force(struct selinux_state *state,
1568 const char *scontext, u32 scontext_len,
1569 u32 *sid)
1570{
1571 return security_context_to_sid_core(state, scontext, scontext_len,
1572 sid, SECSID_NULL, GFP_KERNEL, 1);
1573}
1574
1575static int compute_sid_handle_invalid_context(
1576 struct selinux_state *state,
1577 struct context *scontext,
1578 struct context *tcontext,
1579 u16 tclass,
1580 struct context *newcontext)
1581{
1582 struct policydb *policydb = &state->ss->policydb;
1583 char *s = NULL, *t = NULL, *n = NULL;
1584 u32 slen, tlen, nlen;
1585 struct audit_buffer *ab;
1586
1587 if (context_struct_to_string(policydb, scontext, &s, &slen))
1588 goto out;
1589 if (context_struct_to_string(policydb, tcontext, &t, &tlen))
1590 goto out;
1591 if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1592 goto out;
1593 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR);
1594 audit_log_format(ab,
1595 "op=security_compute_sid invalid_context=");
1596 /* no need to record the NUL with untrusted strings */
1597 audit_log_n_untrustedstring(ab, n, nlen - 1);
1598 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s",
1599 s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1600 audit_log_end(ab);
1601out:
1602 kfree(s);
1603 kfree(t);
1604 kfree(n);
1605 if (!enforcing_enabled(state))
1606 return 0;
1607 return -EACCES;
1608}
1609
1610static void filename_compute_type(struct policydb *policydb,
1611 struct context *newcontext,
1612 u32 stype, u32 ttype, u16 tclass,
1613 const char *objname)
1614{
1615 struct filename_trans ft;
1616 struct filename_trans_datum *otype;
1617
1618 /*
1619 * Most filename trans rules are going to live in specific directories
1620 * like /dev or /var/run. This bitmap will quickly skip rule searches
1621 * if the ttype does not contain any rules.
1622 */
1623 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1624 return;
1625
1626 ft.stype = stype;
1627 ft.ttype = ttype;
1628 ft.tclass = tclass;
1629 ft.name = objname;
1630
1631 otype = hashtab_search(policydb->filename_trans, &ft);
1632 if (otype)
1633 newcontext->type = otype->otype;
1634}
1635
1636static int security_compute_sid(struct selinux_state *state,
1637 u32 ssid,
1638 u32 tsid,
1639 u16 orig_tclass,
1640 u32 specified,
1641 const char *objname,
1642 u32 *out_sid,
1643 bool kern)
1644{
1645 struct policydb *policydb;
1646 struct sidtab *sidtab;
1647 struct class_datum *cladatum = NULL;
1648 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1649 struct role_trans *roletr = NULL;
1650 struct avtab_key avkey;
1651 struct avtab_datum *avdatum;
1652 struct avtab_node *node;
1653 u16 tclass;
1654 int rc = 0;
1655 bool sock;
1656
1657 if (!state->initialized) {
1658 switch (orig_tclass) {
1659 case SECCLASS_PROCESS: /* kernel value */
1660 *out_sid = ssid;
1661 break;
1662 default:
1663 *out_sid = tsid;
1664 break;
1665 }
1666 goto out;
1667 }
1668
1669 context_init(&newcontext);
1670
1671 read_lock(&state->ss->policy_rwlock);
1672
1673 if (kern) {
1674 tclass = unmap_class(&state->ss->map, orig_tclass);
1675 sock = security_is_socket_class(orig_tclass);
1676 } else {
1677 tclass = orig_tclass;
1678 sock = security_is_socket_class(map_class(&state->ss->map,
1679 tclass));
1680 }
1681
1682 policydb = &state->ss->policydb;
1683 sidtab = state->ss->sidtab;
1684
1685 scontext = sidtab_search(sidtab, ssid);
1686 if (!scontext) {
1687 pr_err("SELinux: %s: unrecognized SID %d\n",
1688 __func__, ssid);
1689 rc = -EINVAL;
1690 goto out_unlock;
1691 }
1692 tcontext = sidtab_search(sidtab, tsid);
1693 if (!tcontext) {
1694 pr_err("SELinux: %s: unrecognized SID %d\n",
1695 __func__, tsid);
1696 rc = -EINVAL;
1697 goto out_unlock;
1698 }
1699
1700 if (tclass && tclass <= policydb->p_classes.nprim)
1701 cladatum = policydb->class_val_to_struct[tclass - 1];
1702
1703 /* Set the user identity. */
1704 switch (specified) {
1705 case AVTAB_TRANSITION:
1706 case AVTAB_CHANGE:
1707 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1708 newcontext.user = tcontext->user;
1709 } else {
1710 /* notice this gets both DEFAULT_SOURCE and unset */
1711 /* Use the process user identity. */
1712 newcontext.user = scontext->user;
1713 }
1714 break;
1715 case AVTAB_MEMBER:
1716 /* Use the related object owner. */
1717 newcontext.user = tcontext->user;
1718 break;
1719 }
1720
1721 /* Set the role to default values. */
1722 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1723 newcontext.role = scontext->role;
1724 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1725 newcontext.role = tcontext->role;
1726 } else {
1727 if ((tclass == policydb->process_class) || (sock == true))
1728 newcontext.role = scontext->role;
1729 else
1730 newcontext.role = OBJECT_R_VAL;
1731 }
1732
1733 /* Set the type to default values. */
1734 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1735 newcontext.type = scontext->type;
1736 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1737 newcontext.type = tcontext->type;
1738 } else {
1739 if ((tclass == policydb->process_class) || (sock == true)) {
1740 /* Use the type of process. */
1741 newcontext.type = scontext->type;
1742 } else {
1743 /* Use the type of the related object. */
1744 newcontext.type = tcontext->type;
1745 }
1746 }
1747
1748 /* Look for a type transition/member/change rule. */
1749 avkey.source_type = scontext->type;
1750 avkey.target_type = tcontext->type;
1751 avkey.target_class = tclass;
1752 avkey.specified = specified;
1753 avdatum = avtab_search(&policydb->te_avtab, &avkey);
1754
1755 /* If no permanent rule, also check for enabled conditional rules */
1756 if (!avdatum) {
1757 node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1758 for (; node; node = avtab_search_node_next(node, specified)) {
1759 if (node->key.specified & AVTAB_ENABLED) {
1760 avdatum = &node->datum;
1761 break;
1762 }
1763 }
1764 }
1765
1766 if (avdatum) {
1767 /* Use the type from the type transition/member/change rule. */
1768 newcontext.type = avdatum->u.data;
1769 }
1770
1771 /* if we have a objname this is a file trans check so check those rules */
1772 if (objname)
1773 filename_compute_type(policydb, &newcontext, scontext->type,
1774 tcontext->type, tclass, objname);
1775
1776 /* Check for class-specific changes. */
1777 if (specified & AVTAB_TRANSITION) {
1778 /* Look for a role transition rule. */
1779 for (roletr = policydb->role_tr; roletr;
1780 roletr = roletr->next) {
1781 if ((roletr->role == scontext->role) &&
1782 (roletr->type == tcontext->type) &&
1783 (roletr->tclass == tclass)) {
1784 /* Use the role transition rule. */
1785 newcontext.role = roletr->new_role;
1786 break;
1787 }
1788 }
1789 }
1790
1791 /* Set the MLS attributes.
1792 This is done last because it may allocate memory. */
1793 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1794 &newcontext, sock);
1795 if (rc)
1796 goto out_unlock;
1797
1798 /* Check the validity of the context. */
1799 if (!policydb_context_isvalid(policydb, &newcontext)) {
1800 rc = compute_sid_handle_invalid_context(state, scontext,
1801 tcontext,
1802 tclass,
1803 &newcontext);
1804 if (rc)
1805 goto out_unlock;
1806 }
1807 /* Obtain the sid for the context. */
1808 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1809out_unlock:
1810 read_unlock(&state->ss->policy_rwlock);
1811 context_destroy(&newcontext);
1812out:
1813 return rc;
1814}
1815
1816/**
1817 * security_transition_sid - Compute the SID for a new subject/object.
1818 * @ssid: source security identifier
1819 * @tsid: target security identifier
1820 * @tclass: target security class
1821 * @out_sid: security identifier for new subject/object
1822 *
1823 * Compute a SID to use for labeling a new subject or object in the
1824 * class @tclass based on a SID pair (@ssid, @tsid).
1825 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1826 * if insufficient memory is available, or %0 if the new SID was
1827 * computed successfully.
1828 */
1829int security_transition_sid(struct selinux_state *state,
1830 u32 ssid, u32 tsid, u16 tclass,
1831 const struct qstr *qstr, u32 *out_sid)
1832{
1833 return security_compute_sid(state, ssid, tsid, tclass,
1834 AVTAB_TRANSITION,
1835 qstr ? qstr->name : NULL, out_sid, true);
1836}
1837
1838int security_transition_sid_user(struct selinux_state *state,
1839 u32 ssid, u32 tsid, u16 tclass,
1840 const char *objname, u32 *out_sid)
1841{
1842 return security_compute_sid(state, ssid, tsid, tclass,
1843 AVTAB_TRANSITION,
1844 objname, out_sid, false);
1845}
1846
1847/**
1848 * security_member_sid - Compute the SID for member selection.
1849 * @ssid: source security identifier
1850 * @tsid: target security identifier
1851 * @tclass: target security class
1852 * @out_sid: security identifier for selected member
1853 *
1854 * Compute a SID to use when selecting a member of a polyinstantiated
1855 * object of class @tclass based on a SID pair (@ssid, @tsid).
1856 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1857 * if insufficient memory is available, or %0 if the SID was
1858 * computed successfully.
1859 */
1860int security_member_sid(struct selinux_state *state,
1861 u32 ssid,
1862 u32 tsid,
1863 u16 tclass,
1864 u32 *out_sid)
1865{
1866 return security_compute_sid(state, ssid, tsid, tclass,
1867 AVTAB_MEMBER, NULL,
1868 out_sid, false);
1869}
1870
1871/**
1872 * security_change_sid - Compute the SID for object relabeling.
1873 * @ssid: source security identifier
1874 * @tsid: target security identifier
1875 * @tclass: target security class
1876 * @out_sid: security identifier for selected member
1877 *
1878 * Compute a SID to use for relabeling an object of class @tclass
1879 * based on a SID pair (@ssid, @tsid).
1880 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1881 * if insufficient memory is available, or %0 if the SID was
1882 * computed successfully.
1883 */
1884int security_change_sid(struct selinux_state *state,
1885 u32 ssid,
1886 u32 tsid,
1887 u16 tclass,
1888 u32 *out_sid)
1889{
1890 return security_compute_sid(state,
1891 ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1892 out_sid, false);
1893}
1894
1895static inline int convert_context_handle_invalid_context(
1896 struct selinux_state *state,
1897 struct context *context)
1898{
1899 struct policydb *policydb = &state->ss->policydb;
1900 char *s;
1901 u32 len;
1902
1903 if (enforcing_enabled(state))
1904 return -EINVAL;
1905
1906 if (!context_struct_to_string(policydb, context, &s, &len)) {
1907 pr_warn("SELinux: Context %s would be invalid if enforcing\n",
1908 s);
1909 kfree(s);
1910 }
1911 return 0;
1912}
1913
1914struct convert_context_args {
1915 struct selinux_state *state;
1916 struct policydb *oldp;
1917 struct policydb *newp;
1918};
1919
1920/*
1921 * Convert the values in the security context
1922 * structure `oldc' from the values specified
1923 * in the policy `p->oldp' to the values specified
1924 * in the policy `p->newp', storing the new context
1925 * in `newc'. Verify that the context is valid
1926 * under the new policy.
1927 */
1928static int convert_context(struct context *oldc, struct context *newc, void *p)
1929{
1930 struct convert_context_args *args;
1931 struct ocontext *oc;
1932 struct role_datum *role;
1933 struct type_datum *typdatum;
1934 struct user_datum *usrdatum;
1935 char *s;
1936 u32 len;
1937 int rc;
1938
1939 args = p;
1940
1941 if (oldc->str) {
1942 s = kstrdup(oldc->str, GFP_KERNEL);
1943 if (!s)
1944 return -ENOMEM;
1945
1946 rc = string_to_context_struct(args->newp, NULL, s,
1947 newc, SECSID_NULL);
1948 if (rc == -EINVAL) {
1949 /*
1950 * Retain string representation for later mapping.
1951 *
1952 * IMPORTANT: We need to copy the contents of oldc->str
1953 * back into s again because string_to_context_struct()
1954 * may have garbled it.
1955 */
1956 memcpy(s, oldc->str, oldc->len);
1957 context_init(newc);
1958 newc->str = s;
1959 newc->len = oldc->len;
1960 return 0;
1961 }
1962 kfree(s);
1963 if (rc) {
1964 /* Other error condition, e.g. ENOMEM. */
1965 pr_err("SELinux: Unable to map context %s, rc = %d.\n",
1966 oldc->str, -rc);
1967 return rc;
1968 }
1969 pr_info("SELinux: Context %s became valid (mapped).\n",
1970 oldc->str);
1971 return 0;
1972 }
1973
1974 context_init(newc);
1975
1976 /* Convert the user. */
1977 rc = -EINVAL;
1978 usrdatum = hashtab_search(args->newp->p_users.table,
1979 sym_name(args->oldp,
1980 SYM_USERS, oldc->user - 1));
1981 if (!usrdatum)
1982 goto bad;
1983 newc->user = usrdatum->value;
1984
1985 /* Convert the role. */
1986 rc = -EINVAL;
1987 role = hashtab_search(args->newp->p_roles.table,
1988 sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
1989 if (!role)
1990 goto bad;
1991 newc->role = role->value;
1992
1993 /* Convert the type. */
1994 rc = -EINVAL;
1995 typdatum = hashtab_search(args->newp->p_types.table,
1996 sym_name(args->oldp,
1997 SYM_TYPES, oldc->type - 1));
1998 if (!typdatum)
1999 goto bad;
2000 newc->type = typdatum->value;
2001
2002 /* Convert the MLS fields if dealing with MLS policies */
2003 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2004 rc = mls_convert_context(args->oldp, args->newp, oldc, newc);
2005 if (rc)
2006 goto bad;
2007 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2008 /*
2009 * Switching between non-MLS and MLS policy:
2010 * ensure that the MLS fields of the context for all
2011 * existing entries in the sidtab are filled in with a
2012 * suitable default value, likely taken from one of the
2013 * initial SIDs.
2014 */
2015 oc = args->newp->ocontexts[OCON_ISID];
2016 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2017 oc = oc->next;
2018 rc = -EINVAL;
2019 if (!oc) {
2020 pr_err("SELinux: unable to look up"
2021 " the initial SIDs list\n");
2022 goto bad;
2023 }
2024 rc = mls_range_set(newc, &oc->context[0].range);
2025 if (rc)
2026 goto bad;
2027 }
2028
2029 /* Check the validity of the new context. */
2030 if (!policydb_context_isvalid(args->newp, newc)) {
2031 rc = convert_context_handle_invalid_context(args->state, oldc);
2032 if (rc)
2033 goto bad;
2034 }
2035
2036 return 0;
2037bad:
2038 /* Map old representation to string and save it. */
2039 rc = context_struct_to_string(args->oldp, oldc, &s, &len);
2040 if (rc)
2041 return rc;
2042 context_destroy(newc);
2043 newc->str = s;
2044 newc->len = len;
2045 pr_info("SELinux: Context %s became invalid (unmapped).\n",
2046 newc->str);
2047 return 0;
2048}
2049
2050static void security_load_policycaps(struct selinux_state *state)
2051{
2052 struct policydb *p = &state->ss->policydb;
2053 unsigned int i;
2054 struct ebitmap_node *node;
2055
2056 for (i = 0; i < ARRAY_SIZE(state->policycap); i++)
2057 state->policycap[i] = ebitmap_get_bit(&p->policycaps, i);
2058
2059 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2060 pr_info("SELinux: policy capability %s=%d\n",
2061 selinux_policycap_names[i],
2062 ebitmap_get_bit(&p->policycaps, i));
2063
2064 ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2065 if (i >= ARRAY_SIZE(selinux_policycap_names))
2066 pr_info("SELinux: unknown policy capability %u\n",
2067 i);
2068 }
2069}
2070
2071static int security_preserve_bools(struct selinux_state *state,
2072 struct policydb *newpolicydb);
2073
2074/**
2075 * security_load_policy - Load a security policy configuration.
2076 * @data: binary policy data
2077 * @len: length of data in bytes
2078 *
2079 * Load a new set of security policy configuration data,
2080 * validate it and convert the SID table as necessary.
2081 * This function will flush the access vector cache after
2082 * loading the new policy.
2083 */
2084int security_load_policy(struct selinux_state *state, void *data, size_t len)
2085{
2086 struct policydb *policydb;
2087 struct sidtab *oldsidtab, *newsidtab;
2088 struct policydb *oldpolicydb, *newpolicydb;
2089 struct selinux_mapping *oldmapping;
2090 struct selinux_map newmap;
2091 struct sidtab_convert_params convert_params;
2092 struct convert_context_args args;
2093 u32 seqno;
2094 int rc = 0;
2095 struct policy_file file = { data, len }, *fp = &file;
2096
2097 oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL);
2098 if (!oldpolicydb) {
2099 rc = -ENOMEM;
2100 goto out;
2101 }
2102 newpolicydb = oldpolicydb + 1;
2103
2104 policydb = &state->ss->policydb;
2105
2106 newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL);
2107 if (!newsidtab) {
2108 rc = -ENOMEM;
2109 goto out;
2110 }
2111
2112 if (!state->initialized) {
2113 rc = policydb_read(policydb, fp);
2114 if (rc) {
2115 kfree(newsidtab);
2116 goto out;
2117 }
2118
2119 policydb->len = len;
2120 rc = selinux_set_mapping(policydb, secclass_map,
2121 &state->ss->map);
2122 if (rc) {
2123 kfree(newsidtab);
2124 policydb_destroy(policydb);
2125 goto out;
2126 }
2127
2128 rc = policydb_load_isids(policydb, newsidtab);
2129 if (rc) {
2130 kfree(newsidtab);
2131 policydb_destroy(policydb);
2132 goto out;
2133 }
2134
2135 state->ss->sidtab = newsidtab;
2136 security_load_policycaps(state);
2137 state->initialized = 1;
2138 seqno = ++state->ss->latest_granting;
2139 selinux_complete_init();
2140 avc_ss_reset(state->avc, seqno);
2141 selnl_notify_policyload(seqno);
2142 selinux_status_update_policyload(state, seqno);
2143 selinux_netlbl_cache_invalidate();
2144 selinux_xfrm_notify_policyload();
2145 goto out;
2146 }
2147
2148 rc = policydb_read(newpolicydb, fp);
2149 if (rc) {
2150 kfree(newsidtab);
2151 goto out;
2152 }
2153
2154 newpolicydb->len = len;
2155 /* If switching between different policy types, log MLS status */
2156 if (policydb->mls_enabled && !newpolicydb->mls_enabled)
2157 pr_info("SELinux: Disabling MLS support...\n");
2158 else if (!policydb->mls_enabled && newpolicydb->mls_enabled)
2159 pr_info("SELinux: Enabling MLS support...\n");
2160
2161 rc = policydb_load_isids(newpolicydb, newsidtab);
2162 if (rc) {
2163 pr_err("SELinux: unable to load the initial SIDs\n");
2164 policydb_destroy(newpolicydb);
2165 kfree(newsidtab);
2166 goto out;
2167 }
2168
2169 rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap);
2170 if (rc)
2171 goto err;
2172
2173 rc = security_preserve_bools(state, newpolicydb);
2174 if (rc) {
2175 pr_err("SELinux: unable to preserve booleans\n");
2176 goto err;
2177 }
2178
2179 oldsidtab = state->ss->sidtab;
2180
2181 /*
2182 * Convert the internal representations of contexts
2183 * in the new SID table.
2184 */
2185 args.state = state;
2186 args.oldp = policydb;
2187 args.newp = newpolicydb;
2188
2189 convert_params.func = convert_context;
2190 convert_params.args = &args;
2191 convert_params.target = newsidtab;
2192
2193 rc = sidtab_convert(oldsidtab, &convert_params);
2194 if (rc) {
2195 pr_err("SELinux: unable to convert the internal"
2196 " representation of contexts in the new SID"
2197 " table\n");
2198 goto err;
2199 }
2200
2201 /* Save the old policydb and SID table to free later. */
2202 memcpy(oldpolicydb, policydb, sizeof(*policydb));
2203
2204 /* Install the new policydb and SID table. */
2205 write_lock_irq(&state->ss->policy_rwlock);
2206 memcpy(policydb, newpolicydb, sizeof(*policydb));
2207 state->ss->sidtab = newsidtab;
2208 security_load_policycaps(state);
2209 oldmapping = state->ss->map.mapping;
2210 state->ss->map.mapping = newmap.mapping;
2211 state->ss->map.size = newmap.size;
2212 seqno = ++state->ss->latest_granting;
2213 write_unlock_irq(&state->ss->policy_rwlock);
2214
2215 /* Free the old policydb and SID table. */
2216 policydb_destroy(oldpolicydb);
2217 sidtab_destroy(oldsidtab);
2218 kfree(oldsidtab);
2219 kfree(oldmapping);
2220
2221 avc_ss_reset(state->avc, seqno);
2222 selnl_notify_policyload(seqno);
2223 selinux_status_update_policyload(state, seqno);
2224 selinux_netlbl_cache_invalidate();
2225 selinux_xfrm_notify_policyload();
2226
2227 rc = 0;
2228 goto out;
2229
2230err:
2231 kfree(newmap.mapping);
2232 sidtab_destroy(newsidtab);
2233 kfree(newsidtab);
2234 policydb_destroy(newpolicydb);
2235
2236out:
2237 kfree(oldpolicydb);
2238 return rc;
2239}
2240
2241size_t security_policydb_len(struct selinux_state *state)
2242{
2243 struct policydb *p = &state->ss->policydb;
2244 size_t len;
2245
2246 read_lock(&state->ss->policy_rwlock);
2247 len = p->len;
2248 read_unlock(&state->ss->policy_rwlock);
2249
2250 return len;
2251}
2252
2253/**
2254 * security_port_sid - Obtain the SID for a port.
2255 * @protocol: protocol number
2256 * @port: port number
2257 * @out_sid: security identifier
2258 */
2259int security_port_sid(struct selinux_state *state,
2260 u8 protocol, u16 port, u32 *out_sid)
2261{
2262 struct policydb *policydb;
2263 struct sidtab *sidtab;
2264 struct ocontext *c;
2265 int rc = 0;
2266
2267 read_lock(&state->ss->policy_rwlock);
2268
2269 policydb = &state->ss->policydb;
2270 sidtab = state->ss->sidtab;
2271
2272 c = policydb->ocontexts[OCON_PORT];
2273 while (c) {
2274 if (c->u.port.protocol == protocol &&
2275 c->u.port.low_port <= port &&
2276 c->u.port.high_port >= port)
2277 break;
2278 c = c->next;
2279 }
2280
2281 if (c) {
2282 if (!c->sid[0]) {
2283 rc = sidtab_context_to_sid(sidtab,
2284 &c->context[0],
2285 &c->sid[0]);
2286 if (rc)
2287 goto out;
2288 }
2289 *out_sid = c->sid[0];
2290 } else {
2291 *out_sid = SECINITSID_PORT;
2292 }
2293
2294out:
2295 read_unlock(&state->ss->policy_rwlock);
2296 return rc;
2297}
2298
2299/**
2300 * security_pkey_sid - Obtain the SID for a pkey.
2301 * @subnet_prefix: Subnet Prefix
2302 * @pkey_num: pkey number
2303 * @out_sid: security identifier
2304 */
2305int security_ib_pkey_sid(struct selinux_state *state,
2306 u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2307{
2308 struct policydb *policydb;
2309 struct sidtab *sidtab;
2310 struct ocontext *c;
2311 int rc = 0;
2312
2313 read_lock(&state->ss->policy_rwlock);
2314
2315 policydb = &state->ss->policydb;
2316 sidtab = state->ss->sidtab;
2317
2318 c = policydb->ocontexts[OCON_IBPKEY];
2319 while (c) {
2320 if (c->u.ibpkey.low_pkey <= pkey_num &&
2321 c->u.ibpkey.high_pkey >= pkey_num &&
2322 c->u.ibpkey.subnet_prefix == subnet_prefix)
2323 break;
2324
2325 c = c->next;
2326 }
2327
2328 if (c) {
2329 if (!c->sid[0]) {
2330 rc = sidtab_context_to_sid(sidtab,
2331 &c->context[0],
2332 &c->sid[0]);
2333 if (rc)
2334 goto out;
2335 }
2336 *out_sid = c->sid[0];
2337 } else
2338 *out_sid = SECINITSID_UNLABELED;
2339
2340out:
2341 read_unlock(&state->ss->policy_rwlock);
2342 return rc;
2343}
2344
2345/**
2346 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2347 * @dev_name: device name
2348 * @port: port number
2349 * @out_sid: security identifier
2350 */
2351int security_ib_endport_sid(struct selinux_state *state,
2352 const char *dev_name, u8 port_num, u32 *out_sid)
2353{
2354 struct policydb *policydb;
2355 struct sidtab *sidtab;
2356 struct ocontext *c;
2357 int rc = 0;
2358
2359 read_lock(&state->ss->policy_rwlock);
2360
2361 policydb = &state->ss->policydb;
2362 sidtab = state->ss->sidtab;
2363
2364 c = policydb->ocontexts[OCON_IBENDPORT];
2365 while (c) {
2366 if (c->u.ibendport.port == port_num &&
2367 !strncmp(c->u.ibendport.dev_name,
2368 dev_name,
2369 IB_DEVICE_NAME_MAX))
2370 break;
2371
2372 c = c->next;
2373 }
2374
2375 if (c) {
2376 if (!c->sid[0]) {
2377 rc = sidtab_context_to_sid(sidtab,
2378 &c->context[0],
2379 &c->sid[0]);
2380 if (rc)
2381 goto out;
2382 }
2383 *out_sid = c->sid[0];
2384 } else
2385 *out_sid = SECINITSID_UNLABELED;
2386
2387out:
2388 read_unlock(&state->ss->policy_rwlock);
2389 return rc;
2390}
2391
2392/**
2393 * security_netif_sid - Obtain the SID for a network interface.
2394 * @name: interface name
2395 * @if_sid: interface SID
2396 */
2397int security_netif_sid(struct selinux_state *state,
2398 char *name, u32 *if_sid)
2399{
2400 struct policydb *policydb;
2401 struct sidtab *sidtab;
2402 int rc = 0;
2403 struct ocontext *c;
2404
2405 read_lock(&state->ss->policy_rwlock);
2406
2407 policydb = &state->ss->policydb;
2408 sidtab = state->ss->sidtab;
2409
2410 c = policydb->ocontexts[OCON_NETIF];
2411 while (c) {
2412 if (strcmp(name, c->u.name) == 0)
2413 break;
2414 c = c->next;
2415 }
2416
2417 if (c) {
2418 if (!c->sid[0] || !c->sid[1]) {
2419 rc = sidtab_context_to_sid(sidtab,
2420 &c->context[0],
2421 &c->sid[0]);
2422 if (rc)
2423 goto out;
2424 rc = sidtab_context_to_sid(sidtab,
2425 &c->context[1],
2426 &c->sid[1]);
2427 if (rc)
2428 goto out;
2429 }
2430 *if_sid = c->sid[0];
2431 } else
2432 *if_sid = SECINITSID_NETIF;
2433
2434out:
2435 read_unlock(&state->ss->policy_rwlock);
2436 return rc;
2437}
2438
2439static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2440{
2441 int i, fail = 0;
2442
2443 for (i = 0; i < 4; i++)
2444 if (addr[i] != (input[i] & mask[i])) {
2445 fail = 1;
2446 break;
2447 }
2448
2449 return !fail;
2450}
2451
2452/**
2453 * security_node_sid - Obtain the SID for a node (host).
2454 * @domain: communication domain aka address family
2455 * @addrp: address
2456 * @addrlen: address length in bytes
2457 * @out_sid: security identifier
2458 */
2459int security_node_sid(struct selinux_state *state,
2460 u16 domain,
2461 void *addrp,
2462 u32 addrlen,
2463 u32 *out_sid)
2464{
2465 struct policydb *policydb;
2466 struct sidtab *sidtab;
2467 int rc;
2468 struct ocontext *c;
2469
2470 read_lock(&state->ss->policy_rwlock);
2471
2472 policydb = &state->ss->policydb;
2473 sidtab = state->ss->sidtab;
2474
2475 switch (domain) {
2476 case AF_INET: {
2477 u32 addr;
2478
2479 rc = -EINVAL;
2480 if (addrlen != sizeof(u32))
2481 goto out;
2482
2483 addr = *((u32 *)addrp);
2484
2485 c = policydb->ocontexts[OCON_NODE];
2486 while (c) {
2487 if (c->u.node.addr == (addr & c->u.node.mask))
2488 break;
2489 c = c->next;
2490 }
2491 break;
2492 }
2493
2494 case AF_INET6:
2495 rc = -EINVAL;
2496 if (addrlen != sizeof(u64) * 2)
2497 goto out;
2498 c = policydb->ocontexts[OCON_NODE6];
2499 while (c) {
2500 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2501 c->u.node6.mask))
2502 break;
2503 c = c->next;
2504 }
2505 break;
2506
2507 default:
2508 rc = 0;
2509 *out_sid = SECINITSID_NODE;
2510 goto out;
2511 }
2512
2513 if (c) {
2514 if (!c->sid[0]) {
2515 rc = sidtab_context_to_sid(sidtab,
2516 &c->context[0],
2517 &c->sid[0]);
2518 if (rc)
2519 goto out;
2520 }
2521 *out_sid = c->sid[0];
2522 } else {
2523 *out_sid = SECINITSID_NODE;
2524 }
2525
2526 rc = 0;
2527out:
2528 read_unlock(&state->ss->policy_rwlock);
2529 return rc;
2530}
2531
2532#define SIDS_NEL 25
2533
2534/**
2535 * security_get_user_sids - Obtain reachable SIDs for a user.
2536 * @fromsid: starting SID
2537 * @username: username
2538 * @sids: array of reachable SIDs for user
2539 * @nel: number of elements in @sids
2540 *
2541 * Generate the set of SIDs for legal security contexts
2542 * for a given user that can be reached by @fromsid.
2543 * Set *@sids to point to a dynamically allocated
2544 * array containing the set of SIDs. Set *@nel to the
2545 * number of elements in the array.
2546 */
2547
2548int security_get_user_sids(struct selinux_state *state,
2549 u32 fromsid,
2550 char *username,
2551 u32 **sids,
2552 u32 *nel)
2553{
2554 struct policydb *policydb;
2555 struct sidtab *sidtab;
2556 struct context *fromcon, usercon;
2557 u32 *mysids = NULL, *mysids2, sid;
2558 u32 mynel = 0, maxnel = SIDS_NEL;
2559 struct user_datum *user;
2560 struct role_datum *role;
2561 struct ebitmap_node *rnode, *tnode;
2562 int rc = 0, i, j;
2563
2564 *sids = NULL;
2565 *nel = 0;
2566
2567 if (!state->initialized)
2568 goto out;
2569
2570 read_lock(&state->ss->policy_rwlock);
2571
2572 policydb = &state->ss->policydb;
2573 sidtab = state->ss->sidtab;
2574
2575 context_init(&usercon);
2576
2577 rc = -EINVAL;
2578 fromcon = sidtab_search(sidtab, fromsid);
2579 if (!fromcon)
2580 goto out_unlock;
2581
2582 rc = -EINVAL;
2583 user = hashtab_search(policydb->p_users.table, username);
2584 if (!user)
2585 goto out_unlock;
2586
2587 usercon.user = user->value;
2588
2589 rc = -ENOMEM;
2590 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2591 if (!mysids)
2592 goto out_unlock;
2593
2594 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2595 role = policydb->role_val_to_struct[i];
2596 usercon.role = i + 1;
2597 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2598 usercon.type = j + 1;
2599
2600 if (mls_setup_user_range(policydb, fromcon, user,
2601 &usercon))
2602 continue;
2603
2604 rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2605 if (rc)
2606 goto out_unlock;
2607 if (mynel < maxnel) {
2608 mysids[mynel++] = sid;
2609 } else {
2610 rc = -ENOMEM;
2611 maxnel += SIDS_NEL;
2612 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2613 if (!mysids2)
2614 goto out_unlock;
2615 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2616 kfree(mysids);
2617 mysids = mysids2;
2618 mysids[mynel++] = sid;
2619 }
2620 }
2621 }
2622 rc = 0;
2623out_unlock:
2624 read_unlock(&state->ss->policy_rwlock);
2625 if (rc || !mynel) {
2626 kfree(mysids);
2627 goto out;
2628 }
2629
2630 rc = -ENOMEM;
2631 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2632 if (!mysids2) {
2633 kfree(mysids);
2634 goto out;
2635 }
2636 for (i = 0, j = 0; i < mynel; i++) {
2637 struct av_decision dummy_avd;
2638 rc = avc_has_perm_noaudit(state,
2639 fromsid, mysids[i],
2640 SECCLASS_PROCESS, /* kernel value */
2641 PROCESS__TRANSITION, AVC_STRICT,
2642 &dummy_avd);
2643 if (!rc)
2644 mysids2[j++] = mysids[i];
2645 cond_resched();
2646 }
2647 rc = 0;
2648 kfree(mysids);
2649 *sids = mysids2;
2650 *nel = j;
2651out:
2652 return rc;
2653}
2654
2655/**
2656 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2657 * @fstype: filesystem type
2658 * @path: path from root of mount
2659 * @sclass: file security class
2660 * @sid: SID for path
2661 *
2662 * Obtain a SID to use for a file in a filesystem that
2663 * cannot support xattr or use a fixed labeling behavior like
2664 * transition SIDs or task SIDs.
2665 *
2666 * The caller must acquire the policy_rwlock before calling this function.
2667 */
2668static inline int __security_genfs_sid(struct selinux_state *state,
2669 const char *fstype,
2670 char *path,
2671 u16 orig_sclass,
2672 u32 *sid)
2673{
2674 struct policydb *policydb = &state->ss->policydb;
2675 struct sidtab *sidtab = state->ss->sidtab;
2676 int len;
2677 u16 sclass;
2678 struct genfs *genfs;
2679 struct ocontext *c;
2680 int rc, cmp = 0;
2681
2682 while (path[0] == '/' && path[1] == '/')
2683 path++;
2684
2685 sclass = unmap_class(&state->ss->map, orig_sclass);
2686 *sid = SECINITSID_UNLABELED;
2687
2688 for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2689 cmp = strcmp(fstype, genfs->fstype);
2690 if (cmp <= 0)
2691 break;
2692 }
2693
2694 rc = -ENOENT;
2695 if (!genfs || cmp)
2696 goto out;
2697
2698 for (c = genfs->head; c; c = c->next) {
2699 len = strlen(c->u.name);
2700 if ((!c->v.sclass || sclass == c->v.sclass) &&
2701 (strncmp(c->u.name, path, len) == 0))
2702 break;
2703 }
2704
2705 rc = -ENOENT;
2706 if (!c)
2707 goto out;
2708
2709 if (!c->sid[0]) {
2710 rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]);
2711 if (rc)
2712 goto out;
2713 }
2714
2715 *sid = c->sid[0];
2716 rc = 0;
2717out:
2718 return rc;
2719}
2720
2721/**
2722 * security_genfs_sid - Obtain a SID for a file in a filesystem
2723 * @fstype: filesystem type
2724 * @path: path from root of mount
2725 * @sclass: file security class
2726 * @sid: SID for path
2727 *
2728 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2729 * it afterward.
2730 */
2731int security_genfs_sid(struct selinux_state *state,
2732 const char *fstype,
2733 char *path,
2734 u16 orig_sclass,
2735 u32 *sid)
2736{
2737 int retval;
2738
2739 read_lock(&state->ss->policy_rwlock);
2740 retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid);
2741 read_unlock(&state->ss->policy_rwlock);
2742 return retval;
2743}
2744
2745/**
2746 * security_fs_use - Determine how to handle labeling for a filesystem.
2747 * @sb: superblock in question
2748 */
2749int security_fs_use(struct selinux_state *state, struct super_block *sb)
2750{
2751 struct policydb *policydb;
2752 struct sidtab *sidtab;
2753 int rc = 0;
2754 struct ocontext *c;
2755 struct superblock_security_struct *sbsec = sb->s_security;
2756 const char *fstype = sb->s_type->name;
2757
2758 read_lock(&state->ss->policy_rwlock);
2759
2760 policydb = &state->ss->policydb;
2761 sidtab = state->ss->sidtab;
2762
2763 c = policydb->ocontexts[OCON_FSUSE];
2764 while (c) {
2765 if (strcmp(fstype, c->u.name) == 0)
2766 break;
2767 c = c->next;
2768 }
2769
2770 if (c) {
2771 sbsec->behavior = c->v.behavior;
2772 if (!c->sid[0]) {
2773 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2774 &c->sid[0]);
2775 if (rc)
2776 goto out;
2777 }
2778 sbsec->sid = c->sid[0];
2779 } else {
2780 rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR,
2781 &sbsec->sid);
2782 if (rc) {
2783 sbsec->behavior = SECURITY_FS_USE_NONE;
2784 rc = 0;
2785 } else {
2786 sbsec->behavior = SECURITY_FS_USE_GENFS;
2787 }
2788 }
2789
2790out:
2791 read_unlock(&state->ss->policy_rwlock);
2792 return rc;
2793}
2794
2795int security_get_bools(struct selinux_state *state,
2796 int *len, char ***names, int **values)
2797{
2798 struct policydb *policydb;
2799 int i, rc;
2800
2801 if (!state->initialized) {
2802 *len = 0;
2803 *names = NULL;
2804 *values = NULL;
2805 return 0;
2806 }
2807
2808 read_lock(&state->ss->policy_rwlock);
2809
2810 policydb = &state->ss->policydb;
2811
2812 *names = NULL;
2813 *values = NULL;
2814
2815 rc = 0;
2816 *len = policydb->p_bools.nprim;
2817 if (!*len)
2818 goto out;
2819
2820 rc = -ENOMEM;
2821 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2822 if (!*names)
2823 goto err;
2824
2825 rc = -ENOMEM;
2826 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2827 if (!*values)
2828 goto err;
2829
2830 for (i = 0; i < *len; i++) {
2831 (*values)[i] = policydb->bool_val_to_struct[i]->state;
2832
2833 rc = -ENOMEM;
2834 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
2835 GFP_ATOMIC);
2836 if (!(*names)[i])
2837 goto err;
2838 }
2839 rc = 0;
2840out:
2841 read_unlock(&state->ss->policy_rwlock);
2842 return rc;
2843err:
2844 if (*names) {
2845 for (i = 0; i < *len; i++)
2846 kfree((*names)[i]);
2847 }
2848 kfree(*values);
2849 goto out;
2850}
2851
2852
2853int security_set_bools(struct selinux_state *state, int len, int *values)
2854{
2855 struct policydb *policydb;
2856 int i, rc;
2857 int lenp, seqno = 0;
2858 struct cond_node *cur;
2859
2860 write_lock_irq(&state->ss->policy_rwlock);
2861
2862 policydb = &state->ss->policydb;
2863
2864 rc = -EFAULT;
2865 lenp = policydb->p_bools.nprim;
2866 if (len != lenp)
2867 goto out;
2868
2869 for (i = 0; i < len; i++) {
2870 if (!!values[i] != policydb->bool_val_to_struct[i]->state) {
2871 audit_log(audit_context(), GFP_ATOMIC,
2872 AUDIT_MAC_CONFIG_CHANGE,
2873 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2874 sym_name(policydb, SYM_BOOLS, i),
2875 !!values[i],
2876 policydb->bool_val_to_struct[i]->state,
2877 from_kuid(&init_user_ns, audit_get_loginuid(current)),
2878 audit_get_sessionid(current));
2879 }
2880 if (values[i])
2881 policydb->bool_val_to_struct[i]->state = 1;
2882 else
2883 policydb->bool_val_to_struct[i]->state = 0;
2884 }
2885
2886 for (cur = policydb->cond_list; cur; cur = cur->next) {
2887 rc = evaluate_cond_node(policydb, cur);
2888 if (rc)
2889 goto out;
2890 }
2891
2892 seqno = ++state->ss->latest_granting;
2893 rc = 0;
2894out:
2895 write_unlock_irq(&state->ss->policy_rwlock);
2896 if (!rc) {
2897 avc_ss_reset(state->avc, seqno);
2898 selnl_notify_policyload(seqno);
2899 selinux_status_update_policyload(state, seqno);
2900 selinux_xfrm_notify_policyload();
2901 }
2902 return rc;
2903}
2904
2905int security_get_bool_value(struct selinux_state *state,
2906 int index)
2907{
2908 struct policydb *policydb;
2909 int rc;
2910 int len;
2911
2912 read_lock(&state->ss->policy_rwlock);
2913
2914 policydb = &state->ss->policydb;
2915
2916 rc = -EFAULT;
2917 len = policydb->p_bools.nprim;
2918 if (index >= len)
2919 goto out;
2920
2921 rc = policydb->bool_val_to_struct[index]->state;
2922out:
2923 read_unlock(&state->ss->policy_rwlock);
2924 return rc;
2925}
2926
2927static int security_preserve_bools(struct selinux_state *state,
2928 struct policydb *policydb)
2929{
2930 int rc, nbools = 0, *bvalues = NULL, i;
2931 char **bnames = NULL;
2932 struct cond_bool_datum *booldatum;
2933 struct cond_node *cur;
2934
2935 rc = security_get_bools(state, &nbools, &bnames, &bvalues);
2936 if (rc)
2937 goto out;
2938 for (i = 0; i < nbools; i++) {
2939 booldatum = hashtab_search(policydb->p_bools.table, bnames[i]);
2940 if (booldatum)
2941 booldatum->state = bvalues[i];
2942 }
2943 for (cur = policydb->cond_list; cur; cur = cur->next) {
2944 rc = evaluate_cond_node(policydb, cur);
2945 if (rc)
2946 goto out;
2947 }
2948
2949out:
2950 if (bnames) {
2951 for (i = 0; i < nbools; i++)
2952 kfree(bnames[i]);
2953 }
2954 kfree(bnames);
2955 kfree(bvalues);
2956 return rc;
2957}
2958
2959/*
2960 * security_sid_mls_copy() - computes a new sid based on the given
2961 * sid and the mls portion of mls_sid.
2962 */
2963int security_sid_mls_copy(struct selinux_state *state,
2964 u32 sid, u32 mls_sid, u32 *new_sid)
2965{
2966 struct policydb *policydb = &state->ss->policydb;
2967 struct sidtab *sidtab = state->ss->sidtab;
2968 struct context *context1;
2969 struct context *context2;
2970 struct context newcon;
2971 char *s;
2972 u32 len;
2973 int rc;
2974
2975 rc = 0;
2976 if (!state->initialized || !policydb->mls_enabled) {
2977 *new_sid = sid;
2978 goto out;
2979 }
2980
2981 context_init(&newcon);
2982
2983 read_lock(&state->ss->policy_rwlock);
2984
2985 rc = -EINVAL;
2986 context1 = sidtab_search(sidtab, sid);
2987 if (!context1) {
2988 pr_err("SELinux: %s: unrecognized SID %d\n",
2989 __func__, sid);
2990 goto out_unlock;
2991 }
2992
2993 rc = -EINVAL;
2994 context2 = sidtab_search(sidtab, mls_sid);
2995 if (!context2) {
2996 pr_err("SELinux: %s: unrecognized SID %d\n",
2997 __func__, mls_sid);
2998 goto out_unlock;
2999 }
3000
3001 newcon.user = context1->user;
3002 newcon.role = context1->role;
3003 newcon.type = context1->type;
3004 rc = mls_context_cpy(&newcon, context2);
3005 if (rc)
3006 goto out_unlock;
3007
3008 /* Check the validity of the new context. */
3009 if (!policydb_context_isvalid(policydb, &newcon)) {
3010 rc = convert_context_handle_invalid_context(state, &newcon);
3011 if (rc) {
3012 if (!context_struct_to_string(policydb, &newcon, &s,
3013 &len)) {
3014 struct audit_buffer *ab;
3015
3016 ab = audit_log_start(audit_context(),
3017 GFP_ATOMIC,
3018 AUDIT_SELINUX_ERR);
3019 audit_log_format(ab,
3020 "op=security_sid_mls_copy invalid_context=");
3021 /* don't record NUL with untrusted strings */
3022 audit_log_n_untrustedstring(ab, s, len - 1);
3023 audit_log_end(ab);
3024 kfree(s);
3025 }
3026 goto out_unlock;
3027 }
3028 }
3029
3030 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3031out_unlock:
3032 read_unlock(&state->ss->policy_rwlock);
3033 context_destroy(&newcon);
3034out:
3035 return rc;
3036}
3037
3038/**
3039 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3040 * @nlbl_sid: NetLabel SID
3041 * @nlbl_type: NetLabel labeling protocol type
3042 * @xfrm_sid: XFRM SID
3043 *
3044 * Description:
3045 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3046 * resolved into a single SID it is returned via @peer_sid and the function
3047 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3048 * returns a negative value. A table summarizing the behavior is below:
3049 *
3050 * | function return | @sid
3051 * ------------------------------+-----------------+-----------------
3052 * no peer labels | 0 | SECSID_NULL
3053 * single peer label | 0 | <peer_label>
3054 * multiple, consistent labels | 0 | <peer_label>
3055 * multiple, inconsistent labels | -<errno> | SECSID_NULL
3056 *
3057 */
3058int security_net_peersid_resolve(struct selinux_state *state,
3059 u32 nlbl_sid, u32 nlbl_type,
3060 u32 xfrm_sid,
3061 u32 *peer_sid)
3062{
3063 struct policydb *policydb = &state->ss->policydb;
3064 struct sidtab *sidtab = state->ss->sidtab;
3065 int rc;
3066 struct context *nlbl_ctx;
3067 struct context *xfrm_ctx;
3068
3069 *peer_sid = SECSID_NULL;
3070
3071 /* handle the common (which also happens to be the set of easy) cases
3072 * right away, these two if statements catch everything involving a
3073 * single or absent peer SID/label */
3074 if (xfrm_sid == SECSID_NULL) {
3075 *peer_sid = nlbl_sid;
3076 return 0;
3077 }
3078 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3079 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3080 * is present */
3081 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3082 *peer_sid = xfrm_sid;
3083 return 0;
3084 }
3085
3086 /*
3087 * We don't need to check initialized here since the only way both
3088 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3089 * security server was initialized and state->initialized was true.
3090 */
3091 if (!policydb->mls_enabled)
3092 return 0;
3093
3094 read_lock(&state->ss->policy_rwlock);
3095
3096 rc = -EINVAL;
3097 nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3098 if (!nlbl_ctx) {
3099 pr_err("SELinux: %s: unrecognized SID %d\n",
3100 __func__, nlbl_sid);
3101 goto out;
3102 }
3103 rc = -EINVAL;
3104 xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3105 if (!xfrm_ctx) {
3106 pr_err("SELinux: %s: unrecognized SID %d\n",
3107 __func__, xfrm_sid);
3108 goto out;
3109 }
3110 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3111 if (rc)
3112 goto out;
3113
3114 /* at present NetLabel SIDs/labels really only carry MLS
3115 * information so if the MLS portion of the NetLabel SID
3116 * matches the MLS portion of the labeled XFRM SID/label
3117 * then pass along the XFRM SID as it is the most
3118 * expressive */
3119 *peer_sid = xfrm_sid;
3120out:
3121 read_unlock(&state->ss->policy_rwlock);
3122 return rc;
3123}
3124
3125static int get_classes_callback(void *k, void *d, void *args)
3126{
3127 struct class_datum *datum = d;
3128 char *name = k, **classes = args;
3129 int value = datum->value - 1;
3130
3131 classes[value] = kstrdup(name, GFP_ATOMIC);
3132 if (!classes[value])
3133 return -ENOMEM;
3134
3135 return 0;
3136}
3137
3138int security_get_classes(struct selinux_state *state,
3139 char ***classes, int *nclasses)
3140{
3141 struct policydb *policydb = &state->ss->policydb;
3142 int rc;
3143
3144 if (!state->initialized) {
3145 *nclasses = 0;
3146 *classes = NULL;
3147 return 0;
3148 }
3149
3150 read_lock(&state->ss->policy_rwlock);
3151
3152 rc = -ENOMEM;
3153 *nclasses = policydb->p_classes.nprim;
3154 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3155 if (!*classes)
3156 goto out;
3157
3158 rc = hashtab_map(policydb->p_classes.table, get_classes_callback,
3159 *classes);
3160 if (rc) {
3161 int i;
3162 for (i = 0; i < *nclasses; i++)
3163 kfree((*classes)[i]);
3164 kfree(*classes);
3165 }
3166
3167out:
3168 read_unlock(&state->ss->policy_rwlock);
3169 return rc;
3170}
3171
3172static int get_permissions_callback(void *k, void *d, void *args)
3173{
3174 struct perm_datum *datum = d;
3175 char *name = k, **perms = args;
3176 int value = datum->value - 1;
3177
3178 perms[value] = kstrdup(name, GFP_ATOMIC);
3179 if (!perms[value])
3180 return -ENOMEM;
3181
3182 return 0;
3183}
3184
3185int security_get_permissions(struct selinux_state *state,
3186 char *class, char ***perms, int *nperms)
3187{
3188 struct policydb *policydb = &state->ss->policydb;
3189 int rc, i;
3190 struct class_datum *match;
3191
3192 read_lock(&state->ss->policy_rwlock);
3193
3194 rc = -EINVAL;
3195 match = hashtab_search(policydb->p_classes.table, class);
3196 if (!match) {
3197 pr_err("SELinux: %s: unrecognized class %s\n",
3198 __func__, class);
3199 goto out;
3200 }
3201
3202 rc = -ENOMEM;
3203 *nperms = match->permissions.nprim;
3204 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3205 if (!*perms)
3206 goto out;
3207
3208 if (match->comdatum) {
3209 rc = hashtab_map(match->comdatum->permissions.table,
3210 get_permissions_callback, *perms);
3211 if (rc)
3212 goto err;
3213 }
3214
3215 rc = hashtab_map(match->permissions.table, get_permissions_callback,
3216 *perms);
3217 if (rc)
3218 goto err;
3219
3220out:
3221 read_unlock(&state->ss->policy_rwlock);
3222 return rc;
3223
3224err:
3225 read_unlock(&state->ss->policy_rwlock);
3226 for (i = 0; i < *nperms; i++)
3227 kfree((*perms)[i]);
3228 kfree(*perms);
3229 return rc;
3230}
3231
3232int security_get_reject_unknown(struct selinux_state *state)
3233{
3234 return state->ss->policydb.reject_unknown;
3235}
3236
3237int security_get_allow_unknown(struct selinux_state *state)
3238{
3239 return state->ss->policydb.allow_unknown;
3240}
3241
3242/**
3243 * security_policycap_supported - Check for a specific policy capability
3244 * @req_cap: capability
3245 *
3246 * Description:
3247 * This function queries the currently loaded policy to see if it supports the
3248 * capability specified by @req_cap. Returns true (1) if the capability is
3249 * supported, false (0) if it isn't supported.
3250 *
3251 */
3252int security_policycap_supported(struct selinux_state *state,
3253 unsigned int req_cap)
3254{
3255 struct policydb *policydb = &state->ss->policydb;
3256 int rc;
3257
3258 read_lock(&state->ss->policy_rwlock);
3259 rc = ebitmap_get_bit(&policydb->policycaps, req_cap);
3260 read_unlock(&state->ss->policy_rwlock);
3261
3262 return rc;
3263}
3264
3265struct selinux_audit_rule {
3266 u32 au_seqno;
3267 struct context au_ctxt;
3268};
3269
3270void selinux_audit_rule_free(void *vrule)
3271{
3272 struct selinux_audit_rule *rule = vrule;
3273
3274 if (rule) {
3275 context_destroy(&rule->au_ctxt);
3276 kfree(rule);
3277 }
3278}
3279
3280int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3281{
3282 struct selinux_state *state = &selinux_state;
3283 struct policydb *policydb = &state->ss->policydb;
3284 struct selinux_audit_rule *tmprule;
3285 struct role_datum *roledatum;
3286 struct type_datum *typedatum;
3287 struct user_datum *userdatum;
3288 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3289 int rc = 0;
3290
3291 *rule = NULL;
3292
3293 if (!state->initialized)
3294 return -EOPNOTSUPP;
3295
3296 switch (field) {
3297 case AUDIT_SUBJ_USER:
3298 case AUDIT_SUBJ_ROLE:
3299 case AUDIT_SUBJ_TYPE:
3300 case AUDIT_OBJ_USER:
3301 case AUDIT_OBJ_ROLE:
3302 case AUDIT_OBJ_TYPE:
3303 /* only 'equals' and 'not equals' fit user, role, and type */
3304 if (op != Audit_equal && op != Audit_not_equal)
3305 return -EINVAL;
3306 break;
3307 case AUDIT_SUBJ_SEN:
3308 case AUDIT_SUBJ_CLR:
3309 case AUDIT_OBJ_LEV_LOW:
3310 case AUDIT_OBJ_LEV_HIGH:
3311 /* we do not allow a range, indicated by the presence of '-' */
3312 if (strchr(rulestr, '-'))
3313 return -EINVAL;
3314 break;
3315 default:
3316 /* only the above fields are valid */
3317 return -EINVAL;
3318 }
3319
3320 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3321 if (!tmprule)
3322 return -ENOMEM;
3323
3324 context_init(&tmprule->au_ctxt);
3325
3326 read_lock(&state->ss->policy_rwlock);
3327
3328 tmprule->au_seqno = state->ss->latest_granting;
3329
3330 switch (field) {
3331 case AUDIT_SUBJ_USER:
3332 case AUDIT_OBJ_USER:
3333 rc = -EINVAL;
3334 userdatum = hashtab_search(policydb->p_users.table, rulestr);
3335 if (!userdatum)
3336 goto out;
3337 tmprule->au_ctxt.user = userdatum->value;
3338 break;
3339 case AUDIT_SUBJ_ROLE:
3340 case AUDIT_OBJ_ROLE:
3341 rc = -EINVAL;
3342 roledatum = hashtab_search(policydb->p_roles.table, rulestr);
3343 if (!roledatum)
3344 goto out;
3345 tmprule->au_ctxt.role = roledatum->value;
3346 break;
3347 case AUDIT_SUBJ_TYPE:
3348 case AUDIT_OBJ_TYPE:
3349 rc = -EINVAL;
3350 typedatum = hashtab_search(policydb->p_types.table, rulestr);
3351 if (!typedatum)
3352 goto out;
3353 tmprule->au_ctxt.type = typedatum->value;
3354 break;
3355 case AUDIT_SUBJ_SEN:
3356 case AUDIT_SUBJ_CLR:
3357 case AUDIT_OBJ_LEV_LOW:
3358 case AUDIT_OBJ_LEV_HIGH:
3359 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3360 GFP_ATOMIC);
3361 if (rc)
3362 goto out;
3363 break;
3364 }
3365 rc = 0;
3366out:
3367 read_unlock(&state->ss->policy_rwlock);
3368
3369 if (rc) {
3370 selinux_audit_rule_free(tmprule);
3371 tmprule = NULL;
3372 }
3373
3374 *rule = tmprule;
3375
3376 return rc;
3377}
3378
3379/* Check to see if the rule contains any selinux fields */
3380int selinux_audit_rule_known(struct audit_krule *rule)
3381{
3382 int i;
3383
3384 for (i = 0; i < rule->field_count; i++) {
3385 struct audit_field *f = &rule->fields[i];
3386 switch (f->type) {
3387 case AUDIT_SUBJ_USER:
3388 case AUDIT_SUBJ_ROLE:
3389 case AUDIT_SUBJ_TYPE:
3390 case AUDIT_SUBJ_SEN:
3391 case AUDIT_SUBJ_CLR:
3392 case AUDIT_OBJ_USER:
3393 case AUDIT_OBJ_ROLE:
3394 case AUDIT_OBJ_TYPE:
3395 case AUDIT_OBJ_LEV_LOW:
3396 case AUDIT_OBJ_LEV_HIGH:
3397 return 1;
3398 }
3399 }
3400
3401 return 0;
3402}
3403
3404int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule)
3405{
3406 struct selinux_state *state = &selinux_state;
3407 struct context *ctxt;
3408 struct mls_level *level;
3409 struct selinux_audit_rule *rule = vrule;
3410 int match = 0;
3411
3412 if (unlikely(!rule)) {
3413 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3414 return -ENOENT;
3415 }
3416
3417 read_lock(&state->ss->policy_rwlock);
3418
3419 if (rule->au_seqno < state->ss->latest_granting) {
3420 match = -ESTALE;
3421 goto out;
3422 }
3423
3424 ctxt = sidtab_search(state->ss->sidtab, sid);
3425 if (unlikely(!ctxt)) {
3426 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3427 sid);
3428 match = -ENOENT;
3429 goto out;
3430 }
3431
3432 /* a field/op pair that is not caught here will simply fall through
3433 without a match */
3434 switch (field) {
3435 case AUDIT_SUBJ_USER:
3436 case AUDIT_OBJ_USER:
3437 switch (op) {
3438 case Audit_equal:
3439 match = (ctxt->user == rule->au_ctxt.user);
3440 break;
3441 case Audit_not_equal:
3442 match = (ctxt->user != rule->au_ctxt.user);
3443 break;
3444 }
3445 break;
3446 case AUDIT_SUBJ_ROLE:
3447 case AUDIT_OBJ_ROLE:
3448 switch (op) {
3449 case Audit_equal:
3450 match = (ctxt->role == rule->au_ctxt.role);
3451 break;
3452 case Audit_not_equal:
3453 match = (ctxt->role != rule->au_ctxt.role);
3454 break;
3455 }
3456 break;
3457 case AUDIT_SUBJ_TYPE:
3458 case AUDIT_OBJ_TYPE:
3459 switch (op) {
3460 case Audit_equal:
3461 match = (ctxt->type == rule->au_ctxt.type);
3462 break;
3463 case Audit_not_equal:
3464 match = (ctxt->type != rule->au_ctxt.type);
3465 break;
3466 }
3467 break;
3468 case AUDIT_SUBJ_SEN:
3469 case AUDIT_SUBJ_CLR:
3470 case AUDIT_OBJ_LEV_LOW:
3471 case AUDIT_OBJ_LEV_HIGH:
3472 level = ((field == AUDIT_SUBJ_SEN ||
3473 field == AUDIT_OBJ_LEV_LOW) ?
3474 &ctxt->range.level[0] : &ctxt->range.level[1]);
3475 switch (op) {
3476 case Audit_equal:
3477 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3478 level);
3479 break;
3480 case Audit_not_equal:
3481 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3482 level);
3483 break;
3484 case Audit_lt:
3485 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3486 level) &&
3487 !mls_level_eq(&rule->au_ctxt.range.level[0],
3488 level));
3489 break;
3490 case Audit_le:
3491 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3492 level);
3493 break;
3494 case Audit_gt:
3495 match = (mls_level_dom(level,
3496 &rule->au_ctxt.range.level[0]) &&
3497 !mls_level_eq(level,
3498 &rule->au_ctxt.range.level[0]));
3499 break;
3500 case Audit_ge:
3501 match = mls_level_dom(level,
3502 &rule->au_ctxt.range.level[0]);
3503 break;
3504 }
3505 }
3506
3507out:
3508 read_unlock(&state->ss->policy_rwlock);
3509 return match;
3510}
3511
3512static int (*aurule_callback)(void) = audit_update_lsm_rules;
3513
3514static int aurule_avc_callback(u32 event)
3515{
3516 int err = 0;
3517
3518 if (event == AVC_CALLBACK_RESET && aurule_callback)
3519 err = aurule_callback();
3520 return err;
3521}
3522
3523static int __init aurule_init(void)
3524{
3525 int err;
3526
3527 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3528 if (err)
3529 panic("avc_add_callback() failed, error %d\n", err);
3530
3531 return err;
3532}
3533__initcall(aurule_init);
3534
3535#ifdef CONFIG_NETLABEL
3536/**
3537 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3538 * @secattr: the NetLabel packet security attributes
3539 * @sid: the SELinux SID
3540 *
3541 * Description:
3542 * Attempt to cache the context in @ctx, which was derived from the packet in
3543 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3544 * already been initialized.
3545 *
3546 */
3547static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3548 u32 sid)
3549{
3550 u32 *sid_cache;
3551
3552 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3553 if (sid_cache == NULL)
3554 return;
3555 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3556 if (secattr->cache == NULL) {
3557 kfree(sid_cache);
3558 return;
3559 }
3560
3561 *sid_cache = sid;
3562 secattr->cache->free = kfree;
3563 secattr->cache->data = sid_cache;
3564 secattr->flags |= NETLBL_SECATTR_CACHE;
3565}
3566
3567/**
3568 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3569 * @secattr: the NetLabel packet security attributes
3570 * @sid: the SELinux SID
3571 *
3572 * Description:
3573 * Convert the given NetLabel security attributes in @secattr into a
3574 * SELinux SID. If the @secattr field does not contain a full SELinux
3575 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3576 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3577 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3578 * conversion for future lookups. Returns zero on success, negative values on
3579 * failure.
3580 *
3581 */
3582int security_netlbl_secattr_to_sid(struct selinux_state *state,
3583 struct netlbl_lsm_secattr *secattr,
3584 u32 *sid)
3585{
3586 struct policydb *policydb = &state->ss->policydb;
3587 struct sidtab *sidtab = state->ss->sidtab;
3588 int rc;
3589 struct context *ctx;
3590 struct context ctx_new;
3591
3592 if (!state->initialized) {
3593 *sid = SECSID_NULL;
3594 return 0;
3595 }
3596
3597 read_lock(&state->ss->policy_rwlock);
3598
3599 if (secattr->flags & NETLBL_SECATTR_CACHE)
3600 *sid = *(u32 *)secattr->cache->data;
3601 else if (secattr->flags & NETLBL_SECATTR_SECID)
3602 *sid = secattr->attr.secid;
3603 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3604 rc = -EIDRM;
3605 ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3606 if (ctx == NULL)
3607 goto out;
3608
3609 context_init(&ctx_new);
3610 ctx_new.user = ctx->user;
3611 ctx_new.role = ctx->role;
3612 ctx_new.type = ctx->type;
3613 mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3614 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3615 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3616 if (rc)
3617 goto out;
3618 }
3619 rc = -EIDRM;
3620 if (!mls_context_isvalid(policydb, &ctx_new))
3621 goto out_free;
3622
3623 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3624 if (rc)
3625 goto out_free;
3626
3627 security_netlbl_cache_add(secattr, *sid);
3628
3629 ebitmap_destroy(&ctx_new.range.level[0].cat);
3630 } else
3631 *sid = SECSID_NULL;
3632
3633 read_unlock(&state->ss->policy_rwlock);
3634 return 0;
3635out_free:
3636 ebitmap_destroy(&ctx_new.range.level[0].cat);
3637out:
3638 read_unlock(&state->ss->policy_rwlock);
3639 return rc;
3640}
3641
3642/**
3643 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3644 * @sid: the SELinux SID
3645 * @secattr: the NetLabel packet security attributes
3646 *
3647 * Description:
3648 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3649 * Returns zero on success, negative values on failure.
3650 *
3651 */
3652int security_netlbl_sid_to_secattr(struct selinux_state *state,
3653 u32 sid, struct netlbl_lsm_secattr *secattr)
3654{
3655 struct policydb *policydb = &state->ss->policydb;
3656 int rc;
3657 struct context *ctx;
3658
3659 if (!state->initialized)
3660 return 0;
3661
3662 read_lock(&state->ss->policy_rwlock);
3663
3664 rc = -ENOENT;
3665 ctx = sidtab_search(state->ss->sidtab, sid);
3666 if (ctx == NULL)
3667 goto out;
3668
3669 rc = -ENOMEM;
3670 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3671 GFP_ATOMIC);
3672 if (secattr->domain == NULL)
3673 goto out;
3674
3675 secattr->attr.secid = sid;
3676 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3677 mls_export_netlbl_lvl(policydb, ctx, secattr);
3678 rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3679out:
3680 read_unlock(&state->ss->policy_rwlock);
3681 return rc;
3682}
3683#endif /* CONFIG_NETLABEL */
3684
3685/**
3686 * security_read_policy - read the policy.
3687 * @data: binary policy data
3688 * @len: length of data in bytes
3689 *
3690 */
3691int security_read_policy(struct selinux_state *state,
3692 void **data, size_t *len)
3693{
3694 struct policydb *policydb = &state->ss->policydb;
3695 int rc;
3696 struct policy_file fp;
3697
3698 if (!state->initialized)
3699 return -EINVAL;
3700
3701 *len = security_policydb_len(state);
3702
3703 *data = vmalloc_user(*len);
3704 if (!*data)
3705 return -ENOMEM;
3706
3707 fp.data = *data;
3708 fp.len = *len;
3709
3710 read_lock(&state->ss->policy_rwlock);
3711 rc = policydb_write(policydb, &fp);
3712 read_unlock(&state->ss->policy_rwlock);
3713
3714 if (rc)
3715 return rc;
3716
3717 *len = (unsigned long)fp.data - (unsigned long)*data;
3718 return 0;
3719
3720}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Implementation of the security services.
4 *
5 * Authors : Stephen Smalley, <sds@tycho.nsa.gov>
6 * James Morris <jmorris@redhat.com>
7 *
8 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
9 *
10 * Support for enhanced MLS infrastructure.
11 * Support for context based audit filters.
12 *
13 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
14 *
15 * Added conditional policy language extensions
16 *
17 * Updated: Hewlett-Packard <paul@paul-moore.com>
18 *
19 * Added support for NetLabel
20 * Added support for the policy capability bitmap
21 *
22 * Updated: Chad Sellers <csellers@tresys.com>
23 *
24 * Added validation of kernel classes and permissions
25 *
26 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
27 *
28 * Added support for bounds domain and audit messaged on masked permissions
29 *
30 * Updated: Guido Trentalancia <guido@trentalancia.com>
31 *
32 * Added support for runtime switching of the policy type
33 *
34 * Copyright (C) 2008, 2009 NEC Corporation
35 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
36 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
37 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
38 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
39 */
40#include <linux/kernel.h>
41#include <linux/slab.h>
42#include <linux/string.h>
43#include <linux/spinlock.h>
44#include <linux/rcupdate.h>
45#include <linux/errno.h>
46#include <linux/in.h>
47#include <linux/sched.h>
48#include <linux/audit.h>
49#include <linux/vmalloc.h>
50#include <net/netlabel.h>
51
52#include "flask.h"
53#include "avc.h"
54#include "avc_ss.h"
55#include "security.h"
56#include "context.h"
57#include "policydb.h"
58#include "sidtab.h"
59#include "services.h"
60#include "conditional.h"
61#include "mls.h"
62#include "objsec.h"
63#include "netlabel.h"
64#include "xfrm.h"
65#include "ebitmap.h"
66#include "audit.h"
67
68/* Policy capability names */
69const char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = {
70 "network_peer_controls",
71 "open_perms",
72 "extended_socket_class",
73 "always_check_network",
74 "cgroup_seclabel",
75 "nnp_nosuid_transition",
76 "genfs_seclabel_symlinks"
77};
78
79static struct selinux_ss selinux_ss;
80
81void selinux_ss_init(struct selinux_ss **ss)
82{
83 rwlock_init(&selinux_ss.policy_rwlock);
84 *ss = &selinux_ss;
85}
86
87/* Forward declaration. */
88static int context_struct_to_string(struct policydb *policydb,
89 struct context *context,
90 char **scontext,
91 u32 *scontext_len);
92
93static int sidtab_entry_to_string(struct policydb *policydb,
94 struct sidtab *sidtab,
95 struct sidtab_entry *entry,
96 char **scontext,
97 u32 *scontext_len);
98
99static void context_struct_compute_av(struct policydb *policydb,
100 struct context *scontext,
101 struct context *tcontext,
102 u16 tclass,
103 struct av_decision *avd,
104 struct extended_perms *xperms);
105
106static int selinux_set_mapping(struct policydb *pol,
107 struct security_class_mapping *map,
108 struct selinux_map *out_map)
109{
110 u16 i, j;
111 unsigned k;
112 bool print_unknown_handle = false;
113
114 /* Find number of classes in the input mapping */
115 if (!map)
116 return -EINVAL;
117 i = 0;
118 while (map[i].name)
119 i++;
120
121 /* Allocate space for the class records, plus one for class zero */
122 out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC);
123 if (!out_map->mapping)
124 return -ENOMEM;
125
126 /* Store the raw class and permission values */
127 j = 0;
128 while (map[j].name) {
129 struct security_class_mapping *p_in = map + (j++);
130 struct selinux_mapping *p_out = out_map->mapping + j;
131
132 /* An empty class string skips ahead */
133 if (!strcmp(p_in->name, "")) {
134 p_out->num_perms = 0;
135 continue;
136 }
137
138 p_out->value = string_to_security_class(pol, p_in->name);
139 if (!p_out->value) {
140 pr_info("SELinux: Class %s not defined in policy.\n",
141 p_in->name);
142 if (pol->reject_unknown)
143 goto err;
144 p_out->num_perms = 0;
145 print_unknown_handle = true;
146 continue;
147 }
148
149 k = 0;
150 while (p_in->perms[k]) {
151 /* An empty permission string skips ahead */
152 if (!*p_in->perms[k]) {
153 k++;
154 continue;
155 }
156 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
157 p_in->perms[k]);
158 if (!p_out->perms[k]) {
159 pr_info("SELinux: Permission %s in class %s not defined in policy.\n",
160 p_in->perms[k], p_in->name);
161 if (pol->reject_unknown)
162 goto err;
163 print_unknown_handle = true;
164 }
165
166 k++;
167 }
168 p_out->num_perms = k;
169 }
170
171 if (print_unknown_handle)
172 pr_info("SELinux: the above unknown classes and permissions will be %s\n",
173 pol->allow_unknown ? "allowed" : "denied");
174
175 out_map->size = i;
176 return 0;
177err:
178 kfree(out_map->mapping);
179 out_map->mapping = NULL;
180 return -EINVAL;
181}
182
183/*
184 * Get real, policy values from mapped values
185 */
186
187static u16 unmap_class(struct selinux_map *map, u16 tclass)
188{
189 if (tclass < map->size)
190 return map->mapping[tclass].value;
191
192 return tclass;
193}
194
195/*
196 * Get kernel value for class from its policy value
197 */
198static u16 map_class(struct selinux_map *map, u16 pol_value)
199{
200 u16 i;
201
202 for (i = 1; i < map->size; i++) {
203 if (map->mapping[i].value == pol_value)
204 return i;
205 }
206
207 return SECCLASS_NULL;
208}
209
210static void map_decision(struct selinux_map *map,
211 u16 tclass, struct av_decision *avd,
212 int allow_unknown)
213{
214 if (tclass < map->size) {
215 struct selinux_mapping *mapping = &map->mapping[tclass];
216 unsigned int i, n = mapping->num_perms;
217 u32 result;
218
219 for (i = 0, result = 0; i < n; i++) {
220 if (avd->allowed & mapping->perms[i])
221 result |= 1<<i;
222 if (allow_unknown && !mapping->perms[i])
223 result |= 1<<i;
224 }
225 avd->allowed = result;
226
227 for (i = 0, result = 0; i < n; i++)
228 if (avd->auditallow & mapping->perms[i])
229 result |= 1<<i;
230 avd->auditallow = result;
231
232 for (i = 0, result = 0; i < n; i++) {
233 if (avd->auditdeny & mapping->perms[i])
234 result |= 1<<i;
235 if (!allow_unknown && !mapping->perms[i])
236 result |= 1<<i;
237 }
238 /*
239 * In case the kernel has a bug and requests a permission
240 * between num_perms and the maximum permission number, we
241 * should audit that denial
242 */
243 for (; i < (sizeof(u32)*8); i++)
244 result |= 1<<i;
245 avd->auditdeny = result;
246 }
247}
248
249int security_mls_enabled(struct selinux_state *state)
250{
251 struct policydb *p = &state->ss->policydb;
252
253 return p->mls_enabled;
254}
255
256/*
257 * Return the boolean value of a constraint expression
258 * when it is applied to the specified source and target
259 * security contexts.
260 *
261 * xcontext is a special beast... It is used by the validatetrans rules
262 * only. For these rules, scontext is the context before the transition,
263 * tcontext is the context after the transition, and xcontext is the context
264 * of the process performing the transition. All other callers of
265 * constraint_expr_eval should pass in NULL for xcontext.
266 */
267static int constraint_expr_eval(struct policydb *policydb,
268 struct context *scontext,
269 struct context *tcontext,
270 struct context *xcontext,
271 struct constraint_expr *cexpr)
272{
273 u32 val1, val2;
274 struct context *c;
275 struct role_datum *r1, *r2;
276 struct mls_level *l1, *l2;
277 struct constraint_expr *e;
278 int s[CEXPR_MAXDEPTH];
279 int sp = -1;
280
281 for (e = cexpr; e; e = e->next) {
282 switch (e->expr_type) {
283 case CEXPR_NOT:
284 BUG_ON(sp < 0);
285 s[sp] = !s[sp];
286 break;
287 case CEXPR_AND:
288 BUG_ON(sp < 1);
289 sp--;
290 s[sp] &= s[sp + 1];
291 break;
292 case CEXPR_OR:
293 BUG_ON(sp < 1);
294 sp--;
295 s[sp] |= s[sp + 1];
296 break;
297 case CEXPR_ATTR:
298 if (sp == (CEXPR_MAXDEPTH - 1))
299 return 0;
300 switch (e->attr) {
301 case CEXPR_USER:
302 val1 = scontext->user;
303 val2 = tcontext->user;
304 break;
305 case CEXPR_TYPE:
306 val1 = scontext->type;
307 val2 = tcontext->type;
308 break;
309 case CEXPR_ROLE:
310 val1 = scontext->role;
311 val2 = tcontext->role;
312 r1 = policydb->role_val_to_struct[val1 - 1];
313 r2 = policydb->role_val_to_struct[val2 - 1];
314 switch (e->op) {
315 case CEXPR_DOM:
316 s[++sp] = ebitmap_get_bit(&r1->dominates,
317 val2 - 1);
318 continue;
319 case CEXPR_DOMBY:
320 s[++sp] = ebitmap_get_bit(&r2->dominates,
321 val1 - 1);
322 continue;
323 case CEXPR_INCOMP:
324 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
325 val2 - 1) &&
326 !ebitmap_get_bit(&r2->dominates,
327 val1 - 1));
328 continue;
329 default:
330 break;
331 }
332 break;
333 case CEXPR_L1L2:
334 l1 = &(scontext->range.level[0]);
335 l2 = &(tcontext->range.level[0]);
336 goto mls_ops;
337 case CEXPR_L1H2:
338 l1 = &(scontext->range.level[0]);
339 l2 = &(tcontext->range.level[1]);
340 goto mls_ops;
341 case CEXPR_H1L2:
342 l1 = &(scontext->range.level[1]);
343 l2 = &(tcontext->range.level[0]);
344 goto mls_ops;
345 case CEXPR_H1H2:
346 l1 = &(scontext->range.level[1]);
347 l2 = &(tcontext->range.level[1]);
348 goto mls_ops;
349 case CEXPR_L1H1:
350 l1 = &(scontext->range.level[0]);
351 l2 = &(scontext->range.level[1]);
352 goto mls_ops;
353 case CEXPR_L2H2:
354 l1 = &(tcontext->range.level[0]);
355 l2 = &(tcontext->range.level[1]);
356 goto mls_ops;
357mls_ops:
358 switch (e->op) {
359 case CEXPR_EQ:
360 s[++sp] = mls_level_eq(l1, l2);
361 continue;
362 case CEXPR_NEQ:
363 s[++sp] = !mls_level_eq(l1, l2);
364 continue;
365 case CEXPR_DOM:
366 s[++sp] = mls_level_dom(l1, l2);
367 continue;
368 case CEXPR_DOMBY:
369 s[++sp] = mls_level_dom(l2, l1);
370 continue;
371 case CEXPR_INCOMP:
372 s[++sp] = mls_level_incomp(l2, l1);
373 continue;
374 default:
375 BUG();
376 return 0;
377 }
378 break;
379 default:
380 BUG();
381 return 0;
382 }
383
384 switch (e->op) {
385 case CEXPR_EQ:
386 s[++sp] = (val1 == val2);
387 break;
388 case CEXPR_NEQ:
389 s[++sp] = (val1 != val2);
390 break;
391 default:
392 BUG();
393 return 0;
394 }
395 break;
396 case CEXPR_NAMES:
397 if (sp == (CEXPR_MAXDEPTH-1))
398 return 0;
399 c = scontext;
400 if (e->attr & CEXPR_TARGET)
401 c = tcontext;
402 else if (e->attr & CEXPR_XTARGET) {
403 c = xcontext;
404 if (!c) {
405 BUG();
406 return 0;
407 }
408 }
409 if (e->attr & CEXPR_USER)
410 val1 = c->user;
411 else if (e->attr & CEXPR_ROLE)
412 val1 = c->role;
413 else if (e->attr & CEXPR_TYPE)
414 val1 = c->type;
415 else {
416 BUG();
417 return 0;
418 }
419
420 switch (e->op) {
421 case CEXPR_EQ:
422 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
423 break;
424 case CEXPR_NEQ:
425 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
426 break;
427 default:
428 BUG();
429 return 0;
430 }
431 break;
432 default:
433 BUG();
434 return 0;
435 }
436 }
437
438 BUG_ON(sp != 0);
439 return s[0];
440}
441
442/*
443 * security_dump_masked_av - dumps masked permissions during
444 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
445 */
446static int dump_masked_av_helper(void *k, void *d, void *args)
447{
448 struct perm_datum *pdatum = d;
449 char **permission_names = args;
450
451 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
452
453 permission_names[pdatum->value - 1] = (char *)k;
454
455 return 0;
456}
457
458static void security_dump_masked_av(struct policydb *policydb,
459 struct context *scontext,
460 struct context *tcontext,
461 u16 tclass,
462 u32 permissions,
463 const char *reason)
464{
465 struct common_datum *common_dat;
466 struct class_datum *tclass_dat;
467 struct audit_buffer *ab;
468 char *tclass_name;
469 char *scontext_name = NULL;
470 char *tcontext_name = NULL;
471 char *permission_names[32];
472 int index;
473 u32 length;
474 bool need_comma = false;
475
476 if (!permissions)
477 return;
478
479 tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1);
480 tclass_dat = policydb->class_val_to_struct[tclass - 1];
481 common_dat = tclass_dat->comdatum;
482
483 /* init permission_names */
484 if (common_dat &&
485 hashtab_map(&common_dat->permissions.table,
486 dump_masked_av_helper, permission_names) < 0)
487 goto out;
488
489 if (hashtab_map(&tclass_dat->permissions.table,
490 dump_masked_av_helper, permission_names) < 0)
491 goto out;
492
493 /* get scontext/tcontext in text form */
494 if (context_struct_to_string(policydb, scontext,
495 &scontext_name, &length) < 0)
496 goto out;
497
498 if (context_struct_to_string(policydb, tcontext,
499 &tcontext_name, &length) < 0)
500 goto out;
501
502 /* audit a message */
503 ab = audit_log_start(audit_context(),
504 GFP_ATOMIC, AUDIT_SELINUX_ERR);
505 if (!ab)
506 goto out;
507
508 audit_log_format(ab, "op=security_compute_av reason=%s "
509 "scontext=%s tcontext=%s tclass=%s perms=",
510 reason, scontext_name, tcontext_name, tclass_name);
511
512 for (index = 0; index < 32; index++) {
513 u32 mask = (1 << index);
514
515 if ((mask & permissions) == 0)
516 continue;
517
518 audit_log_format(ab, "%s%s",
519 need_comma ? "," : "",
520 permission_names[index]
521 ? permission_names[index] : "????");
522 need_comma = true;
523 }
524 audit_log_end(ab);
525out:
526 /* release scontext/tcontext */
527 kfree(tcontext_name);
528 kfree(scontext_name);
529
530 return;
531}
532
533/*
534 * security_boundary_permission - drops violated permissions
535 * on boundary constraint.
536 */
537static void type_attribute_bounds_av(struct policydb *policydb,
538 struct context *scontext,
539 struct context *tcontext,
540 u16 tclass,
541 struct av_decision *avd)
542{
543 struct context lo_scontext;
544 struct context lo_tcontext, *tcontextp = tcontext;
545 struct av_decision lo_avd;
546 struct type_datum *source;
547 struct type_datum *target;
548 u32 masked = 0;
549
550 source = policydb->type_val_to_struct[scontext->type - 1];
551 BUG_ON(!source);
552
553 if (!source->bounds)
554 return;
555
556 target = policydb->type_val_to_struct[tcontext->type - 1];
557 BUG_ON(!target);
558
559 memset(&lo_avd, 0, sizeof(lo_avd));
560
561 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
562 lo_scontext.type = source->bounds;
563
564 if (target->bounds) {
565 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
566 lo_tcontext.type = target->bounds;
567 tcontextp = &lo_tcontext;
568 }
569
570 context_struct_compute_av(policydb, &lo_scontext,
571 tcontextp,
572 tclass,
573 &lo_avd,
574 NULL);
575
576 masked = ~lo_avd.allowed & avd->allowed;
577
578 if (likely(!masked))
579 return; /* no masked permission */
580
581 /* mask violated permissions */
582 avd->allowed &= ~masked;
583
584 /* audit masked permissions */
585 security_dump_masked_av(policydb, scontext, tcontext,
586 tclass, masked, "bounds");
587}
588
589/*
590 * flag which drivers have permissions
591 * only looking for ioctl based extended permssions
592 */
593void services_compute_xperms_drivers(
594 struct extended_perms *xperms,
595 struct avtab_node *node)
596{
597 unsigned int i;
598
599 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
600 /* if one or more driver has all permissions allowed */
601 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
602 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
603 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
604 /* if allowing permissions within a driver */
605 security_xperm_set(xperms->drivers.p,
606 node->datum.u.xperms->driver);
607 }
608
609 /* If no ioctl commands are allowed, ignore auditallow and auditdeny */
610 if (node->key.specified & AVTAB_XPERMS_ALLOWED)
611 xperms->len = 1;
612}
613
614/*
615 * Compute access vectors and extended permissions based on a context
616 * structure pair for the permissions in a particular class.
617 */
618static void context_struct_compute_av(struct policydb *policydb,
619 struct context *scontext,
620 struct context *tcontext,
621 u16 tclass,
622 struct av_decision *avd,
623 struct extended_perms *xperms)
624{
625 struct constraint_node *constraint;
626 struct role_allow *ra;
627 struct avtab_key avkey;
628 struct avtab_node *node;
629 struct class_datum *tclass_datum;
630 struct ebitmap *sattr, *tattr;
631 struct ebitmap_node *snode, *tnode;
632 unsigned int i, j;
633
634 avd->allowed = 0;
635 avd->auditallow = 0;
636 avd->auditdeny = 0xffffffff;
637 if (xperms) {
638 memset(&xperms->drivers, 0, sizeof(xperms->drivers));
639 xperms->len = 0;
640 }
641
642 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
643 if (printk_ratelimit())
644 pr_warn("SELinux: Invalid class %hu\n", tclass);
645 return;
646 }
647
648 tclass_datum = policydb->class_val_to_struct[tclass - 1];
649
650 /*
651 * If a specific type enforcement rule was defined for
652 * this permission check, then use it.
653 */
654 avkey.target_class = tclass;
655 avkey.specified = AVTAB_AV | AVTAB_XPERMS;
656 sattr = &policydb->type_attr_map_array[scontext->type - 1];
657 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
658 ebitmap_for_each_positive_bit(sattr, snode, i) {
659 ebitmap_for_each_positive_bit(tattr, tnode, j) {
660 avkey.source_type = i + 1;
661 avkey.target_type = j + 1;
662 for (node = avtab_search_node(&policydb->te_avtab,
663 &avkey);
664 node;
665 node = avtab_search_node_next(node, avkey.specified)) {
666 if (node->key.specified == AVTAB_ALLOWED)
667 avd->allowed |= node->datum.u.data;
668 else if (node->key.specified == AVTAB_AUDITALLOW)
669 avd->auditallow |= node->datum.u.data;
670 else if (node->key.specified == AVTAB_AUDITDENY)
671 avd->auditdeny &= node->datum.u.data;
672 else if (xperms && (node->key.specified & AVTAB_XPERMS))
673 services_compute_xperms_drivers(xperms, node);
674 }
675
676 /* Check conditional av table for additional permissions */
677 cond_compute_av(&policydb->te_cond_avtab, &avkey,
678 avd, xperms);
679
680 }
681 }
682
683 /*
684 * Remove any permissions prohibited by a constraint (this includes
685 * the MLS policy).
686 */
687 constraint = tclass_datum->constraints;
688 while (constraint) {
689 if ((constraint->permissions & (avd->allowed)) &&
690 !constraint_expr_eval(policydb, scontext, tcontext, NULL,
691 constraint->expr)) {
692 avd->allowed &= ~(constraint->permissions);
693 }
694 constraint = constraint->next;
695 }
696
697 /*
698 * If checking process transition permission and the
699 * role is changing, then check the (current_role, new_role)
700 * pair.
701 */
702 if (tclass == policydb->process_class &&
703 (avd->allowed & policydb->process_trans_perms) &&
704 scontext->role != tcontext->role) {
705 for (ra = policydb->role_allow; ra; ra = ra->next) {
706 if (scontext->role == ra->role &&
707 tcontext->role == ra->new_role)
708 break;
709 }
710 if (!ra)
711 avd->allowed &= ~policydb->process_trans_perms;
712 }
713
714 /*
715 * If the given source and target types have boundary
716 * constraint, lazy checks have to mask any violated
717 * permission and notice it to userspace via audit.
718 */
719 type_attribute_bounds_av(policydb, scontext, tcontext,
720 tclass, avd);
721}
722
723static int security_validtrans_handle_fail(struct selinux_state *state,
724 struct sidtab_entry *oentry,
725 struct sidtab_entry *nentry,
726 struct sidtab_entry *tentry,
727 u16 tclass)
728{
729 struct policydb *p = &state->ss->policydb;
730 struct sidtab *sidtab = state->ss->sidtab;
731 char *o = NULL, *n = NULL, *t = NULL;
732 u32 olen, nlen, tlen;
733
734 if (sidtab_entry_to_string(p, sidtab, oentry, &o, &olen))
735 goto out;
736 if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen))
737 goto out;
738 if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen))
739 goto out;
740 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
741 "op=security_validate_transition seresult=denied"
742 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
743 o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
744out:
745 kfree(o);
746 kfree(n);
747 kfree(t);
748
749 if (!enforcing_enabled(state))
750 return 0;
751 return -EPERM;
752}
753
754static int security_compute_validatetrans(struct selinux_state *state,
755 u32 oldsid, u32 newsid, u32 tasksid,
756 u16 orig_tclass, bool user)
757{
758 struct policydb *policydb;
759 struct sidtab *sidtab;
760 struct sidtab_entry *oentry;
761 struct sidtab_entry *nentry;
762 struct sidtab_entry *tentry;
763 struct class_datum *tclass_datum;
764 struct constraint_node *constraint;
765 u16 tclass;
766 int rc = 0;
767
768
769 if (!selinux_initialized(state))
770 return 0;
771
772 read_lock(&state->ss->policy_rwlock);
773
774 policydb = &state->ss->policydb;
775 sidtab = state->ss->sidtab;
776
777 if (!user)
778 tclass = unmap_class(&state->ss->map, orig_tclass);
779 else
780 tclass = orig_tclass;
781
782 if (!tclass || tclass > policydb->p_classes.nprim) {
783 rc = -EINVAL;
784 goto out;
785 }
786 tclass_datum = policydb->class_val_to_struct[tclass - 1];
787
788 oentry = sidtab_search_entry(sidtab, oldsid);
789 if (!oentry) {
790 pr_err("SELinux: %s: unrecognized SID %d\n",
791 __func__, oldsid);
792 rc = -EINVAL;
793 goto out;
794 }
795
796 nentry = sidtab_search_entry(sidtab, newsid);
797 if (!nentry) {
798 pr_err("SELinux: %s: unrecognized SID %d\n",
799 __func__, newsid);
800 rc = -EINVAL;
801 goto out;
802 }
803
804 tentry = sidtab_search_entry(sidtab, tasksid);
805 if (!tentry) {
806 pr_err("SELinux: %s: unrecognized SID %d\n",
807 __func__, tasksid);
808 rc = -EINVAL;
809 goto out;
810 }
811
812 constraint = tclass_datum->validatetrans;
813 while (constraint) {
814 if (!constraint_expr_eval(policydb, &oentry->context,
815 &nentry->context, &tentry->context,
816 constraint->expr)) {
817 if (user)
818 rc = -EPERM;
819 else
820 rc = security_validtrans_handle_fail(state,
821 oentry,
822 nentry,
823 tentry,
824 tclass);
825 goto out;
826 }
827 constraint = constraint->next;
828 }
829
830out:
831 read_unlock(&state->ss->policy_rwlock);
832 return rc;
833}
834
835int security_validate_transition_user(struct selinux_state *state,
836 u32 oldsid, u32 newsid, u32 tasksid,
837 u16 tclass)
838{
839 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
840 tclass, true);
841}
842
843int security_validate_transition(struct selinux_state *state,
844 u32 oldsid, u32 newsid, u32 tasksid,
845 u16 orig_tclass)
846{
847 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
848 orig_tclass, false);
849}
850
851/*
852 * security_bounded_transition - check whether the given
853 * transition is directed to bounded, or not.
854 * It returns 0, if @newsid is bounded by @oldsid.
855 * Otherwise, it returns error code.
856 *
857 * @oldsid : current security identifier
858 * @newsid : destinated security identifier
859 */
860int security_bounded_transition(struct selinux_state *state,
861 u32 old_sid, u32 new_sid)
862{
863 struct policydb *policydb;
864 struct sidtab *sidtab;
865 struct sidtab_entry *old_entry, *new_entry;
866 struct type_datum *type;
867 int index;
868 int rc;
869
870 if (!selinux_initialized(state))
871 return 0;
872
873 read_lock(&state->ss->policy_rwlock);
874
875 policydb = &state->ss->policydb;
876 sidtab = state->ss->sidtab;
877
878 rc = -EINVAL;
879 old_entry = sidtab_search_entry(sidtab, old_sid);
880 if (!old_entry) {
881 pr_err("SELinux: %s: unrecognized SID %u\n",
882 __func__, old_sid);
883 goto out;
884 }
885
886 rc = -EINVAL;
887 new_entry = sidtab_search_entry(sidtab, new_sid);
888 if (!new_entry) {
889 pr_err("SELinux: %s: unrecognized SID %u\n",
890 __func__, new_sid);
891 goto out;
892 }
893
894 rc = 0;
895 /* type/domain unchanged */
896 if (old_entry->context.type == new_entry->context.type)
897 goto out;
898
899 index = new_entry->context.type;
900 while (true) {
901 type = policydb->type_val_to_struct[index - 1];
902 BUG_ON(!type);
903
904 /* not bounded anymore */
905 rc = -EPERM;
906 if (!type->bounds)
907 break;
908
909 /* @newsid is bounded by @oldsid */
910 rc = 0;
911 if (type->bounds == old_entry->context.type)
912 break;
913
914 index = type->bounds;
915 }
916
917 if (rc) {
918 char *old_name = NULL;
919 char *new_name = NULL;
920 u32 length;
921
922 if (!sidtab_entry_to_string(policydb, sidtab, old_entry,
923 &old_name, &length) &&
924 !sidtab_entry_to_string(policydb, sidtab, new_entry,
925 &new_name, &length)) {
926 audit_log(audit_context(),
927 GFP_ATOMIC, AUDIT_SELINUX_ERR,
928 "op=security_bounded_transition "
929 "seresult=denied "
930 "oldcontext=%s newcontext=%s",
931 old_name, new_name);
932 }
933 kfree(new_name);
934 kfree(old_name);
935 }
936out:
937 read_unlock(&state->ss->policy_rwlock);
938
939 return rc;
940}
941
942static void avd_init(struct selinux_state *state, struct av_decision *avd)
943{
944 avd->allowed = 0;
945 avd->auditallow = 0;
946 avd->auditdeny = 0xffffffff;
947 avd->seqno = state->ss->latest_granting;
948 avd->flags = 0;
949}
950
951void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
952 struct avtab_node *node)
953{
954 unsigned int i;
955
956 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
957 if (xpermd->driver != node->datum.u.xperms->driver)
958 return;
959 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
960 if (!security_xperm_test(node->datum.u.xperms->perms.p,
961 xpermd->driver))
962 return;
963 } else {
964 BUG();
965 }
966
967 if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
968 xpermd->used |= XPERMS_ALLOWED;
969 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
970 memset(xpermd->allowed->p, 0xff,
971 sizeof(xpermd->allowed->p));
972 }
973 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
974 for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++)
975 xpermd->allowed->p[i] |=
976 node->datum.u.xperms->perms.p[i];
977 }
978 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
979 xpermd->used |= XPERMS_AUDITALLOW;
980 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
981 memset(xpermd->auditallow->p, 0xff,
982 sizeof(xpermd->auditallow->p));
983 }
984 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
985 for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++)
986 xpermd->auditallow->p[i] |=
987 node->datum.u.xperms->perms.p[i];
988 }
989 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
990 xpermd->used |= XPERMS_DONTAUDIT;
991 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
992 memset(xpermd->dontaudit->p, 0xff,
993 sizeof(xpermd->dontaudit->p));
994 }
995 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
996 for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++)
997 xpermd->dontaudit->p[i] |=
998 node->datum.u.xperms->perms.p[i];
999 }
1000 } else {
1001 BUG();
1002 }
1003}
1004
1005void security_compute_xperms_decision(struct selinux_state *state,
1006 u32 ssid,
1007 u32 tsid,
1008 u16 orig_tclass,
1009 u8 driver,
1010 struct extended_perms_decision *xpermd)
1011{
1012 struct policydb *policydb;
1013 struct sidtab *sidtab;
1014 u16 tclass;
1015 struct context *scontext, *tcontext;
1016 struct avtab_key avkey;
1017 struct avtab_node *node;
1018 struct ebitmap *sattr, *tattr;
1019 struct ebitmap_node *snode, *tnode;
1020 unsigned int i, j;
1021
1022 xpermd->driver = driver;
1023 xpermd->used = 0;
1024 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1025 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1026 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1027
1028 read_lock(&state->ss->policy_rwlock);
1029 if (!selinux_initialized(state))
1030 goto allow;
1031
1032 policydb = &state->ss->policydb;
1033 sidtab = state->ss->sidtab;
1034
1035 scontext = sidtab_search(sidtab, ssid);
1036 if (!scontext) {
1037 pr_err("SELinux: %s: unrecognized SID %d\n",
1038 __func__, ssid);
1039 goto out;
1040 }
1041
1042 tcontext = sidtab_search(sidtab, tsid);
1043 if (!tcontext) {
1044 pr_err("SELinux: %s: unrecognized SID %d\n",
1045 __func__, tsid);
1046 goto out;
1047 }
1048
1049 tclass = unmap_class(&state->ss->map, orig_tclass);
1050 if (unlikely(orig_tclass && !tclass)) {
1051 if (policydb->allow_unknown)
1052 goto allow;
1053 goto out;
1054 }
1055
1056
1057 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1058 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1059 goto out;
1060 }
1061
1062 avkey.target_class = tclass;
1063 avkey.specified = AVTAB_XPERMS;
1064 sattr = &policydb->type_attr_map_array[scontext->type - 1];
1065 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
1066 ebitmap_for_each_positive_bit(sattr, snode, i) {
1067 ebitmap_for_each_positive_bit(tattr, tnode, j) {
1068 avkey.source_type = i + 1;
1069 avkey.target_type = j + 1;
1070 for (node = avtab_search_node(&policydb->te_avtab,
1071 &avkey);
1072 node;
1073 node = avtab_search_node_next(node, avkey.specified))
1074 services_compute_xperms_decision(xpermd, node);
1075
1076 cond_compute_xperms(&policydb->te_cond_avtab,
1077 &avkey, xpermd);
1078 }
1079 }
1080out:
1081 read_unlock(&state->ss->policy_rwlock);
1082 return;
1083allow:
1084 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1085 goto out;
1086}
1087
1088/**
1089 * security_compute_av - Compute access vector decisions.
1090 * @ssid: source security identifier
1091 * @tsid: target security identifier
1092 * @tclass: target security class
1093 * @avd: access vector decisions
1094 * @xperms: extended permissions
1095 *
1096 * Compute a set of access vector decisions based on the
1097 * SID pair (@ssid, @tsid) for the permissions in @tclass.
1098 */
1099void security_compute_av(struct selinux_state *state,
1100 u32 ssid,
1101 u32 tsid,
1102 u16 orig_tclass,
1103 struct av_decision *avd,
1104 struct extended_perms *xperms)
1105{
1106 struct policydb *policydb;
1107 struct sidtab *sidtab;
1108 u16 tclass;
1109 struct context *scontext = NULL, *tcontext = NULL;
1110
1111 read_lock(&state->ss->policy_rwlock);
1112 avd_init(state, avd);
1113 xperms->len = 0;
1114 if (!selinux_initialized(state))
1115 goto allow;
1116
1117 policydb = &state->ss->policydb;
1118 sidtab = state->ss->sidtab;
1119
1120 scontext = sidtab_search(sidtab, ssid);
1121 if (!scontext) {
1122 pr_err("SELinux: %s: unrecognized SID %d\n",
1123 __func__, ssid);
1124 goto out;
1125 }
1126
1127 /* permissive domain? */
1128 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1129 avd->flags |= AVD_FLAGS_PERMISSIVE;
1130
1131 tcontext = sidtab_search(sidtab, tsid);
1132 if (!tcontext) {
1133 pr_err("SELinux: %s: unrecognized SID %d\n",
1134 __func__, tsid);
1135 goto out;
1136 }
1137
1138 tclass = unmap_class(&state->ss->map, orig_tclass);
1139 if (unlikely(orig_tclass && !tclass)) {
1140 if (policydb->allow_unknown)
1141 goto allow;
1142 goto out;
1143 }
1144 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1145 xperms);
1146 map_decision(&state->ss->map, orig_tclass, avd,
1147 policydb->allow_unknown);
1148out:
1149 read_unlock(&state->ss->policy_rwlock);
1150 return;
1151allow:
1152 avd->allowed = 0xffffffff;
1153 goto out;
1154}
1155
1156void security_compute_av_user(struct selinux_state *state,
1157 u32 ssid,
1158 u32 tsid,
1159 u16 tclass,
1160 struct av_decision *avd)
1161{
1162 struct policydb *policydb;
1163 struct sidtab *sidtab;
1164 struct context *scontext = NULL, *tcontext = NULL;
1165
1166 read_lock(&state->ss->policy_rwlock);
1167 avd_init(state, avd);
1168 if (!selinux_initialized(state))
1169 goto allow;
1170
1171 policydb = &state->ss->policydb;
1172 sidtab = state->ss->sidtab;
1173
1174 scontext = sidtab_search(sidtab, ssid);
1175 if (!scontext) {
1176 pr_err("SELinux: %s: unrecognized SID %d\n",
1177 __func__, ssid);
1178 goto out;
1179 }
1180
1181 /* permissive domain? */
1182 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1183 avd->flags |= AVD_FLAGS_PERMISSIVE;
1184
1185 tcontext = sidtab_search(sidtab, tsid);
1186 if (!tcontext) {
1187 pr_err("SELinux: %s: unrecognized SID %d\n",
1188 __func__, tsid);
1189 goto out;
1190 }
1191
1192 if (unlikely(!tclass)) {
1193 if (policydb->allow_unknown)
1194 goto allow;
1195 goto out;
1196 }
1197
1198 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1199 NULL);
1200 out:
1201 read_unlock(&state->ss->policy_rwlock);
1202 return;
1203allow:
1204 avd->allowed = 0xffffffff;
1205 goto out;
1206}
1207
1208/*
1209 * Write the security context string representation of
1210 * the context structure `context' into a dynamically
1211 * allocated string of the correct size. Set `*scontext'
1212 * to point to this string and set `*scontext_len' to
1213 * the length of the string.
1214 */
1215static int context_struct_to_string(struct policydb *p,
1216 struct context *context,
1217 char **scontext, u32 *scontext_len)
1218{
1219 char *scontextp;
1220
1221 if (scontext)
1222 *scontext = NULL;
1223 *scontext_len = 0;
1224
1225 if (context->len) {
1226 *scontext_len = context->len;
1227 if (scontext) {
1228 *scontext = kstrdup(context->str, GFP_ATOMIC);
1229 if (!(*scontext))
1230 return -ENOMEM;
1231 }
1232 return 0;
1233 }
1234
1235 /* Compute the size of the context. */
1236 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1237 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1238 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1239 *scontext_len += mls_compute_context_len(p, context);
1240
1241 if (!scontext)
1242 return 0;
1243
1244 /* Allocate space for the context; caller must free this space. */
1245 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1246 if (!scontextp)
1247 return -ENOMEM;
1248 *scontext = scontextp;
1249
1250 /*
1251 * Copy the user name, role name and type name into the context.
1252 */
1253 scontextp += sprintf(scontextp, "%s:%s:%s",
1254 sym_name(p, SYM_USERS, context->user - 1),
1255 sym_name(p, SYM_ROLES, context->role - 1),
1256 sym_name(p, SYM_TYPES, context->type - 1));
1257
1258 mls_sid_to_context(p, context, &scontextp);
1259
1260 *scontextp = 0;
1261
1262 return 0;
1263}
1264
1265static int sidtab_entry_to_string(struct policydb *p,
1266 struct sidtab *sidtab,
1267 struct sidtab_entry *entry,
1268 char **scontext, u32 *scontext_len)
1269{
1270 int rc = sidtab_sid2str_get(sidtab, entry, scontext, scontext_len);
1271
1272 if (rc != -ENOENT)
1273 return rc;
1274
1275 rc = context_struct_to_string(p, &entry->context, scontext,
1276 scontext_len);
1277 if (!rc && scontext)
1278 sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len);
1279 return rc;
1280}
1281
1282#include "initial_sid_to_string.h"
1283
1284int security_sidtab_hash_stats(struct selinux_state *state, char *page)
1285{
1286 int rc;
1287
1288 if (!selinux_initialized(state)) {
1289 pr_err("SELinux: %s: called before initial load_policy\n",
1290 __func__);
1291 return -EINVAL;
1292 }
1293
1294 read_lock(&state->ss->policy_rwlock);
1295 rc = sidtab_hash_stats(state->ss->sidtab, page);
1296 read_unlock(&state->ss->policy_rwlock);
1297
1298 return rc;
1299}
1300
1301const char *security_get_initial_sid_context(u32 sid)
1302{
1303 if (unlikely(sid > SECINITSID_NUM))
1304 return NULL;
1305 return initial_sid_to_string[sid];
1306}
1307
1308static int security_sid_to_context_core(struct selinux_state *state,
1309 u32 sid, char **scontext,
1310 u32 *scontext_len, int force,
1311 int only_invalid)
1312{
1313 struct policydb *policydb;
1314 struct sidtab *sidtab;
1315 struct sidtab_entry *entry;
1316 int rc = 0;
1317
1318 if (scontext)
1319 *scontext = NULL;
1320 *scontext_len = 0;
1321
1322 if (!selinux_initialized(state)) {
1323 if (sid <= SECINITSID_NUM) {
1324 char *scontextp;
1325 const char *s = initial_sid_to_string[sid];
1326
1327 if (!s)
1328 return -EINVAL;
1329 *scontext_len = strlen(s) + 1;
1330 if (!scontext)
1331 return 0;
1332 scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC);
1333 if (!scontextp)
1334 return -ENOMEM;
1335 *scontext = scontextp;
1336 return 0;
1337 }
1338 pr_err("SELinux: %s: called before initial "
1339 "load_policy on unknown SID %d\n", __func__, sid);
1340 return -EINVAL;
1341 }
1342 read_lock(&state->ss->policy_rwlock);
1343 policydb = &state->ss->policydb;
1344 sidtab = state->ss->sidtab;
1345
1346 if (force)
1347 entry = sidtab_search_entry_force(sidtab, sid);
1348 else
1349 entry = sidtab_search_entry(sidtab, sid);
1350 if (!entry) {
1351 pr_err("SELinux: %s: unrecognized SID %d\n",
1352 __func__, sid);
1353 rc = -EINVAL;
1354 goto out_unlock;
1355 }
1356 if (only_invalid && !entry->context.len)
1357 goto out_unlock;
1358
1359 rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext,
1360 scontext_len);
1361
1362out_unlock:
1363 read_unlock(&state->ss->policy_rwlock);
1364 return rc;
1365
1366}
1367
1368/**
1369 * security_sid_to_context - Obtain a context for a given SID.
1370 * @sid: security identifier, SID
1371 * @scontext: security context
1372 * @scontext_len: length in bytes
1373 *
1374 * Write the string representation of the context associated with @sid
1375 * into a dynamically allocated string of the correct size. Set @scontext
1376 * to point to this string and set @scontext_len to the length of the string.
1377 */
1378int security_sid_to_context(struct selinux_state *state,
1379 u32 sid, char **scontext, u32 *scontext_len)
1380{
1381 return security_sid_to_context_core(state, sid, scontext,
1382 scontext_len, 0, 0);
1383}
1384
1385int security_sid_to_context_force(struct selinux_state *state, u32 sid,
1386 char **scontext, u32 *scontext_len)
1387{
1388 return security_sid_to_context_core(state, sid, scontext,
1389 scontext_len, 1, 0);
1390}
1391
1392/**
1393 * security_sid_to_context_inval - Obtain a context for a given SID if it
1394 * is invalid.
1395 * @sid: security identifier, SID
1396 * @scontext: security context
1397 * @scontext_len: length in bytes
1398 *
1399 * Write the string representation of the context associated with @sid
1400 * into a dynamically allocated string of the correct size, but only if the
1401 * context is invalid in the current policy. Set @scontext to point to
1402 * this string (or NULL if the context is valid) and set @scontext_len to
1403 * the length of the string (or 0 if the context is valid).
1404 */
1405int security_sid_to_context_inval(struct selinux_state *state, u32 sid,
1406 char **scontext, u32 *scontext_len)
1407{
1408 return security_sid_to_context_core(state, sid, scontext,
1409 scontext_len, 1, 1);
1410}
1411
1412/*
1413 * Caveat: Mutates scontext.
1414 */
1415static int string_to_context_struct(struct policydb *pol,
1416 struct sidtab *sidtabp,
1417 char *scontext,
1418 struct context *ctx,
1419 u32 def_sid)
1420{
1421 struct role_datum *role;
1422 struct type_datum *typdatum;
1423 struct user_datum *usrdatum;
1424 char *scontextp, *p, oldc;
1425 int rc = 0;
1426
1427 context_init(ctx);
1428
1429 /* Parse the security context. */
1430
1431 rc = -EINVAL;
1432 scontextp = (char *) scontext;
1433
1434 /* Extract the user. */
1435 p = scontextp;
1436 while (*p && *p != ':')
1437 p++;
1438
1439 if (*p == 0)
1440 goto out;
1441
1442 *p++ = 0;
1443
1444 usrdatum = symtab_search(&pol->p_users, scontextp);
1445 if (!usrdatum)
1446 goto out;
1447
1448 ctx->user = usrdatum->value;
1449
1450 /* Extract role. */
1451 scontextp = p;
1452 while (*p && *p != ':')
1453 p++;
1454
1455 if (*p == 0)
1456 goto out;
1457
1458 *p++ = 0;
1459
1460 role = symtab_search(&pol->p_roles, scontextp);
1461 if (!role)
1462 goto out;
1463 ctx->role = role->value;
1464
1465 /* Extract type. */
1466 scontextp = p;
1467 while (*p && *p != ':')
1468 p++;
1469 oldc = *p;
1470 *p++ = 0;
1471
1472 typdatum = symtab_search(&pol->p_types, scontextp);
1473 if (!typdatum || typdatum->attribute)
1474 goto out;
1475
1476 ctx->type = typdatum->value;
1477
1478 rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid);
1479 if (rc)
1480 goto out;
1481
1482 /* Check the validity of the new context. */
1483 rc = -EINVAL;
1484 if (!policydb_context_isvalid(pol, ctx))
1485 goto out;
1486 rc = 0;
1487out:
1488 if (rc)
1489 context_destroy(ctx);
1490 return rc;
1491}
1492
1493static int security_context_to_sid_core(struct selinux_state *state,
1494 const char *scontext, u32 scontext_len,
1495 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1496 int force)
1497{
1498 struct policydb *policydb;
1499 struct sidtab *sidtab;
1500 char *scontext2, *str = NULL;
1501 struct context context;
1502 int rc = 0;
1503
1504 /* An empty security context is never valid. */
1505 if (!scontext_len)
1506 return -EINVAL;
1507
1508 /* Copy the string to allow changes and ensure a NUL terminator */
1509 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags);
1510 if (!scontext2)
1511 return -ENOMEM;
1512
1513 if (!selinux_initialized(state)) {
1514 int i;
1515
1516 for (i = 1; i < SECINITSID_NUM; i++) {
1517 const char *s = initial_sid_to_string[i];
1518
1519 if (s && !strcmp(s, scontext2)) {
1520 *sid = i;
1521 goto out;
1522 }
1523 }
1524 *sid = SECINITSID_KERNEL;
1525 goto out;
1526 }
1527 *sid = SECSID_NULL;
1528
1529 if (force) {
1530 /* Save another copy for storing in uninterpreted form */
1531 rc = -ENOMEM;
1532 str = kstrdup(scontext2, gfp_flags);
1533 if (!str)
1534 goto out;
1535 }
1536 read_lock(&state->ss->policy_rwlock);
1537 policydb = &state->ss->policydb;
1538 sidtab = state->ss->sidtab;
1539 rc = string_to_context_struct(policydb, sidtab, scontext2,
1540 &context, def_sid);
1541 if (rc == -EINVAL && force) {
1542 context.str = str;
1543 context.len = strlen(str) + 1;
1544 str = NULL;
1545 } else if (rc)
1546 goto out_unlock;
1547 rc = sidtab_context_to_sid(sidtab, &context, sid);
1548 context_destroy(&context);
1549out_unlock:
1550 read_unlock(&state->ss->policy_rwlock);
1551out:
1552 kfree(scontext2);
1553 kfree(str);
1554 return rc;
1555}
1556
1557/**
1558 * security_context_to_sid - Obtain a SID for a given security context.
1559 * @scontext: security context
1560 * @scontext_len: length in bytes
1561 * @sid: security identifier, SID
1562 * @gfp: context for the allocation
1563 *
1564 * Obtains a SID associated with the security context that
1565 * has the string representation specified by @scontext.
1566 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1567 * memory is available, or 0 on success.
1568 */
1569int security_context_to_sid(struct selinux_state *state,
1570 const char *scontext, u32 scontext_len, u32 *sid,
1571 gfp_t gfp)
1572{
1573 return security_context_to_sid_core(state, scontext, scontext_len,
1574 sid, SECSID_NULL, gfp, 0);
1575}
1576
1577int security_context_str_to_sid(struct selinux_state *state,
1578 const char *scontext, u32 *sid, gfp_t gfp)
1579{
1580 return security_context_to_sid(state, scontext, strlen(scontext),
1581 sid, gfp);
1582}
1583
1584/**
1585 * security_context_to_sid_default - Obtain a SID for a given security context,
1586 * falling back to specified default if needed.
1587 *
1588 * @scontext: security context
1589 * @scontext_len: length in bytes
1590 * @sid: security identifier, SID
1591 * @def_sid: default SID to assign on error
1592 *
1593 * Obtains a SID associated with the security context that
1594 * has the string representation specified by @scontext.
1595 * The default SID is passed to the MLS layer to be used to allow
1596 * kernel labeling of the MLS field if the MLS field is not present
1597 * (for upgrading to MLS without full relabel).
1598 * Implicitly forces adding of the context even if it cannot be mapped yet.
1599 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1600 * memory is available, or 0 on success.
1601 */
1602int security_context_to_sid_default(struct selinux_state *state,
1603 const char *scontext, u32 scontext_len,
1604 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1605{
1606 return security_context_to_sid_core(state, scontext, scontext_len,
1607 sid, def_sid, gfp_flags, 1);
1608}
1609
1610int security_context_to_sid_force(struct selinux_state *state,
1611 const char *scontext, u32 scontext_len,
1612 u32 *sid)
1613{
1614 return security_context_to_sid_core(state, scontext, scontext_len,
1615 sid, SECSID_NULL, GFP_KERNEL, 1);
1616}
1617
1618static int compute_sid_handle_invalid_context(
1619 struct selinux_state *state,
1620 struct sidtab_entry *sentry,
1621 struct sidtab_entry *tentry,
1622 u16 tclass,
1623 struct context *newcontext)
1624{
1625 struct policydb *policydb = &state->ss->policydb;
1626 struct sidtab *sidtab = state->ss->sidtab;
1627 char *s = NULL, *t = NULL, *n = NULL;
1628 u32 slen, tlen, nlen;
1629 struct audit_buffer *ab;
1630
1631 if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen))
1632 goto out;
1633 if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen))
1634 goto out;
1635 if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1636 goto out;
1637 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR);
1638 audit_log_format(ab,
1639 "op=security_compute_sid invalid_context=");
1640 /* no need to record the NUL with untrusted strings */
1641 audit_log_n_untrustedstring(ab, n, nlen - 1);
1642 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s",
1643 s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1644 audit_log_end(ab);
1645out:
1646 kfree(s);
1647 kfree(t);
1648 kfree(n);
1649 if (!enforcing_enabled(state))
1650 return 0;
1651 return -EACCES;
1652}
1653
1654static void filename_compute_type(struct policydb *policydb,
1655 struct context *newcontext,
1656 u32 stype, u32 ttype, u16 tclass,
1657 const char *objname)
1658{
1659 struct filename_trans_key ft;
1660 struct filename_trans_datum *datum;
1661
1662 /*
1663 * Most filename trans rules are going to live in specific directories
1664 * like /dev or /var/run. This bitmap will quickly skip rule searches
1665 * if the ttype does not contain any rules.
1666 */
1667 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1668 return;
1669
1670 ft.ttype = ttype;
1671 ft.tclass = tclass;
1672 ft.name = objname;
1673
1674 datum = policydb_filenametr_search(policydb, &ft);
1675 while (datum) {
1676 if (ebitmap_get_bit(&datum->stypes, stype - 1)) {
1677 newcontext->type = datum->otype;
1678 return;
1679 }
1680 datum = datum->next;
1681 }
1682}
1683
1684static int security_compute_sid(struct selinux_state *state,
1685 u32 ssid,
1686 u32 tsid,
1687 u16 orig_tclass,
1688 u32 specified,
1689 const char *objname,
1690 u32 *out_sid,
1691 bool kern)
1692{
1693 struct policydb *policydb;
1694 struct sidtab *sidtab;
1695 struct class_datum *cladatum = NULL;
1696 struct context *scontext, *tcontext, newcontext;
1697 struct sidtab_entry *sentry, *tentry;
1698 struct avtab_key avkey;
1699 struct avtab_datum *avdatum;
1700 struct avtab_node *node;
1701 u16 tclass;
1702 int rc = 0;
1703 bool sock;
1704
1705 if (!selinux_initialized(state)) {
1706 switch (orig_tclass) {
1707 case SECCLASS_PROCESS: /* kernel value */
1708 *out_sid = ssid;
1709 break;
1710 default:
1711 *out_sid = tsid;
1712 break;
1713 }
1714 goto out;
1715 }
1716
1717 context_init(&newcontext);
1718
1719 read_lock(&state->ss->policy_rwlock);
1720
1721 if (kern) {
1722 tclass = unmap_class(&state->ss->map, orig_tclass);
1723 sock = security_is_socket_class(orig_tclass);
1724 } else {
1725 tclass = orig_tclass;
1726 sock = security_is_socket_class(map_class(&state->ss->map,
1727 tclass));
1728 }
1729
1730 policydb = &state->ss->policydb;
1731 sidtab = state->ss->sidtab;
1732
1733 sentry = sidtab_search_entry(sidtab, ssid);
1734 if (!sentry) {
1735 pr_err("SELinux: %s: unrecognized SID %d\n",
1736 __func__, ssid);
1737 rc = -EINVAL;
1738 goto out_unlock;
1739 }
1740 tentry = sidtab_search_entry(sidtab, tsid);
1741 if (!tentry) {
1742 pr_err("SELinux: %s: unrecognized SID %d\n",
1743 __func__, tsid);
1744 rc = -EINVAL;
1745 goto out_unlock;
1746 }
1747
1748 scontext = &sentry->context;
1749 tcontext = &tentry->context;
1750
1751 if (tclass && tclass <= policydb->p_classes.nprim)
1752 cladatum = policydb->class_val_to_struct[tclass - 1];
1753
1754 /* Set the user identity. */
1755 switch (specified) {
1756 case AVTAB_TRANSITION:
1757 case AVTAB_CHANGE:
1758 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1759 newcontext.user = tcontext->user;
1760 } else {
1761 /* notice this gets both DEFAULT_SOURCE and unset */
1762 /* Use the process user identity. */
1763 newcontext.user = scontext->user;
1764 }
1765 break;
1766 case AVTAB_MEMBER:
1767 /* Use the related object owner. */
1768 newcontext.user = tcontext->user;
1769 break;
1770 }
1771
1772 /* Set the role to default values. */
1773 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1774 newcontext.role = scontext->role;
1775 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1776 newcontext.role = tcontext->role;
1777 } else {
1778 if ((tclass == policydb->process_class) || sock)
1779 newcontext.role = scontext->role;
1780 else
1781 newcontext.role = OBJECT_R_VAL;
1782 }
1783
1784 /* Set the type to default values. */
1785 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1786 newcontext.type = scontext->type;
1787 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1788 newcontext.type = tcontext->type;
1789 } else {
1790 if ((tclass == policydb->process_class) || sock) {
1791 /* Use the type of process. */
1792 newcontext.type = scontext->type;
1793 } else {
1794 /* Use the type of the related object. */
1795 newcontext.type = tcontext->type;
1796 }
1797 }
1798
1799 /* Look for a type transition/member/change rule. */
1800 avkey.source_type = scontext->type;
1801 avkey.target_type = tcontext->type;
1802 avkey.target_class = tclass;
1803 avkey.specified = specified;
1804 avdatum = avtab_search(&policydb->te_avtab, &avkey);
1805
1806 /* If no permanent rule, also check for enabled conditional rules */
1807 if (!avdatum) {
1808 node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1809 for (; node; node = avtab_search_node_next(node, specified)) {
1810 if (node->key.specified & AVTAB_ENABLED) {
1811 avdatum = &node->datum;
1812 break;
1813 }
1814 }
1815 }
1816
1817 if (avdatum) {
1818 /* Use the type from the type transition/member/change rule. */
1819 newcontext.type = avdatum->u.data;
1820 }
1821
1822 /* if we have a objname this is a file trans check so check those rules */
1823 if (objname)
1824 filename_compute_type(policydb, &newcontext, scontext->type,
1825 tcontext->type, tclass, objname);
1826
1827 /* Check for class-specific changes. */
1828 if (specified & AVTAB_TRANSITION) {
1829 /* Look for a role transition rule. */
1830 struct role_trans_datum *rtd;
1831 struct role_trans_key rtk = {
1832 .role = scontext->role,
1833 .type = tcontext->type,
1834 .tclass = tclass,
1835 };
1836
1837 rtd = policydb_roletr_search(policydb, &rtk);
1838 if (rtd)
1839 newcontext.role = rtd->new_role;
1840 }
1841
1842 /* Set the MLS attributes.
1843 This is done last because it may allocate memory. */
1844 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1845 &newcontext, sock);
1846 if (rc)
1847 goto out_unlock;
1848
1849 /* Check the validity of the context. */
1850 if (!policydb_context_isvalid(policydb, &newcontext)) {
1851 rc = compute_sid_handle_invalid_context(state, sentry, tentry,
1852 tclass, &newcontext);
1853 if (rc)
1854 goto out_unlock;
1855 }
1856 /* Obtain the sid for the context. */
1857 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1858out_unlock:
1859 read_unlock(&state->ss->policy_rwlock);
1860 context_destroy(&newcontext);
1861out:
1862 return rc;
1863}
1864
1865/**
1866 * security_transition_sid - Compute the SID for a new subject/object.
1867 * @ssid: source security identifier
1868 * @tsid: target security identifier
1869 * @tclass: target security class
1870 * @out_sid: security identifier for new subject/object
1871 *
1872 * Compute a SID to use for labeling a new subject or object in the
1873 * class @tclass based on a SID pair (@ssid, @tsid).
1874 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1875 * if insufficient memory is available, or %0 if the new SID was
1876 * computed successfully.
1877 */
1878int security_transition_sid(struct selinux_state *state,
1879 u32 ssid, u32 tsid, u16 tclass,
1880 const struct qstr *qstr, u32 *out_sid)
1881{
1882 return security_compute_sid(state, ssid, tsid, tclass,
1883 AVTAB_TRANSITION,
1884 qstr ? qstr->name : NULL, out_sid, true);
1885}
1886
1887int security_transition_sid_user(struct selinux_state *state,
1888 u32 ssid, u32 tsid, u16 tclass,
1889 const char *objname, u32 *out_sid)
1890{
1891 return security_compute_sid(state, ssid, tsid, tclass,
1892 AVTAB_TRANSITION,
1893 objname, out_sid, false);
1894}
1895
1896/**
1897 * security_member_sid - Compute the SID for member selection.
1898 * @ssid: source security identifier
1899 * @tsid: target security identifier
1900 * @tclass: target security class
1901 * @out_sid: security identifier for selected member
1902 *
1903 * Compute a SID to use when selecting a member of a polyinstantiated
1904 * object of class @tclass based on a SID pair (@ssid, @tsid).
1905 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1906 * if insufficient memory is available, or %0 if the SID was
1907 * computed successfully.
1908 */
1909int security_member_sid(struct selinux_state *state,
1910 u32 ssid,
1911 u32 tsid,
1912 u16 tclass,
1913 u32 *out_sid)
1914{
1915 return security_compute_sid(state, ssid, tsid, tclass,
1916 AVTAB_MEMBER, NULL,
1917 out_sid, false);
1918}
1919
1920/**
1921 * security_change_sid - Compute the SID for object relabeling.
1922 * @ssid: source security identifier
1923 * @tsid: target security identifier
1924 * @tclass: target security class
1925 * @out_sid: security identifier for selected member
1926 *
1927 * Compute a SID to use for relabeling an object of class @tclass
1928 * based on a SID pair (@ssid, @tsid).
1929 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1930 * if insufficient memory is available, or %0 if the SID was
1931 * computed successfully.
1932 */
1933int security_change_sid(struct selinux_state *state,
1934 u32 ssid,
1935 u32 tsid,
1936 u16 tclass,
1937 u32 *out_sid)
1938{
1939 return security_compute_sid(state,
1940 ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1941 out_sid, false);
1942}
1943
1944static inline int convert_context_handle_invalid_context(
1945 struct selinux_state *state,
1946 struct context *context)
1947{
1948 struct policydb *policydb = &state->ss->policydb;
1949 char *s;
1950 u32 len;
1951
1952 if (enforcing_enabled(state))
1953 return -EINVAL;
1954
1955 if (!context_struct_to_string(policydb, context, &s, &len)) {
1956 pr_warn("SELinux: Context %s would be invalid if enforcing\n",
1957 s);
1958 kfree(s);
1959 }
1960 return 0;
1961}
1962
1963struct convert_context_args {
1964 struct selinux_state *state;
1965 struct policydb *oldp;
1966 struct policydb *newp;
1967};
1968
1969/*
1970 * Convert the values in the security context
1971 * structure `oldc' from the values specified
1972 * in the policy `p->oldp' to the values specified
1973 * in the policy `p->newp', storing the new context
1974 * in `newc'. Verify that the context is valid
1975 * under the new policy.
1976 */
1977static int convert_context(struct context *oldc, struct context *newc, void *p)
1978{
1979 struct convert_context_args *args;
1980 struct ocontext *oc;
1981 struct role_datum *role;
1982 struct type_datum *typdatum;
1983 struct user_datum *usrdatum;
1984 char *s;
1985 u32 len;
1986 int rc;
1987
1988 args = p;
1989
1990 if (oldc->str) {
1991 s = kstrdup(oldc->str, GFP_KERNEL);
1992 if (!s)
1993 return -ENOMEM;
1994
1995 rc = string_to_context_struct(args->newp, NULL, s,
1996 newc, SECSID_NULL);
1997 if (rc == -EINVAL) {
1998 /*
1999 * Retain string representation for later mapping.
2000 *
2001 * IMPORTANT: We need to copy the contents of oldc->str
2002 * back into s again because string_to_context_struct()
2003 * may have garbled it.
2004 */
2005 memcpy(s, oldc->str, oldc->len);
2006 context_init(newc);
2007 newc->str = s;
2008 newc->len = oldc->len;
2009 return 0;
2010 }
2011 kfree(s);
2012 if (rc) {
2013 /* Other error condition, e.g. ENOMEM. */
2014 pr_err("SELinux: Unable to map context %s, rc = %d.\n",
2015 oldc->str, -rc);
2016 return rc;
2017 }
2018 pr_info("SELinux: Context %s became valid (mapped).\n",
2019 oldc->str);
2020 return 0;
2021 }
2022
2023 context_init(newc);
2024
2025 /* Convert the user. */
2026 rc = -EINVAL;
2027 usrdatum = symtab_search(&args->newp->p_users,
2028 sym_name(args->oldp,
2029 SYM_USERS, oldc->user - 1));
2030 if (!usrdatum)
2031 goto bad;
2032 newc->user = usrdatum->value;
2033
2034 /* Convert the role. */
2035 rc = -EINVAL;
2036 role = symtab_search(&args->newp->p_roles,
2037 sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
2038 if (!role)
2039 goto bad;
2040 newc->role = role->value;
2041
2042 /* Convert the type. */
2043 rc = -EINVAL;
2044 typdatum = symtab_search(&args->newp->p_types,
2045 sym_name(args->oldp,
2046 SYM_TYPES, oldc->type - 1));
2047 if (!typdatum)
2048 goto bad;
2049 newc->type = typdatum->value;
2050
2051 /* Convert the MLS fields if dealing with MLS policies */
2052 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2053 rc = mls_convert_context(args->oldp, args->newp, oldc, newc);
2054 if (rc)
2055 goto bad;
2056 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2057 /*
2058 * Switching between non-MLS and MLS policy:
2059 * ensure that the MLS fields of the context for all
2060 * existing entries in the sidtab are filled in with a
2061 * suitable default value, likely taken from one of the
2062 * initial SIDs.
2063 */
2064 oc = args->newp->ocontexts[OCON_ISID];
2065 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2066 oc = oc->next;
2067 rc = -EINVAL;
2068 if (!oc) {
2069 pr_err("SELinux: unable to look up"
2070 " the initial SIDs list\n");
2071 goto bad;
2072 }
2073 rc = mls_range_set(newc, &oc->context[0].range);
2074 if (rc)
2075 goto bad;
2076 }
2077
2078 /* Check the validity of the new context. */
2079 if (!policydb_context_isvalid(args->newp, newc)) {
2080 rc = convert_context_handle_invalid_context(args->state, oldc);
2081 if (rc)
2082 goto bad;
2083 }
2084
2085 return 0;
2086bad:
2087 /* Map old representation to string and save it. */
2088 rc = context_struct_to_string(args->oldp, oldc, &s, &len);
2089 if (rc)
2090 return rc;
2091 context_destroy(newc);
2092 newc->str = s;
2093 newc->len = len;
2094 pr_info("SELinux: Context %s became invalid (unmapped).\n",
2095 newc->str);
2096 return 0;
2097}
2098
2099static void security_load_policycaps(struct selinux_state *state)
2100{
2101 struct policydb *p = &state->ss->policydb;
2102 unsigned int i;
2103 struct ebitmap_node *node;
2104
2105 for (i = 0; i < ARRAY_SIZE(state->policycap); i++)
2106 state->policycap[i] = ebitmap_get_bit(&p->policycaps, i);
2107
2108 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2109 pr_info("SELinux: policy capability %s=%d\n",
2110 selinux_policycap_names[i],
2111 ebitmap_get_bit(&p->policycaps, i));
2112
2113 ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2114 if (i >= ARRAY_SIZE(selinux_policycap_names))
2115 pr_info("SELinux: unknown policy capability %u\n",
2116 i);
2117 }
2118}
2119
2120static int security_preserve_bools(struct selinux_state *state,
2121 struct policydb *newpolicydb);
2122
2123/**
2124 * security_load_policy - Load a security policy configuration.
2125 * @data: binary policy data
2126 * @len: length of data in bytes
2127 *
2128 * Load a new set of security policy configuration data,
2129 * validate it and convert the SID table as necessary.
2130 * This function will flush the access vector cache after
2131 * loading the new policy.
2132 */
2133int security_load_policy(struct selinux_state *state, void *data, size_t len)
2134{
2135 struct policydb *policydb;
2136 struct sidtab *oldsidtab, *newsidtab;
2137 struct policydb *oldpolicydb, *newpolicydb;
2138 struct selinux_mapping *oldmapping;
2139 struct selinux_map newmap;
2140 struct sidtab_convert_params convert_params;
2141 struct convert_context_args args;
2142 u32 seqno;
2143 int rc = 0;
2144 struct policy_file file = { data, len }, *fp = &file;
2145
2146 policydb = &state->ss->policydb;
2147
2148 newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL);
2149 if (!newsidtab)
2150 return -ENOMEM;
2151
2152 if (!selinux_initialized(state)) {
2153 rc = policydb_read(policydb, fp);
2154 if (rc) {
2155 kfree(newsidtab);
2156 return rc;
2157 }
2158
2159 policydb->len = len;
2160 rc = selinux_set_mapping(policydb, secclass_map,
2161 &state->ss->map);
2162 if (rc) {
2163 kfree(newsidtab);
2164 policydb_destroy(policydb);
2165 return rc;
2166 }
2167
2168 rc = policydb_load_isids(policydb, newsidtab);
2169 if (rc) {
2170 kfree(newsidtab);
2171 policydb_destroy(policydb);
2172 return rc;
2173 }
2174
2175 state->ss->sidtab = newsidtab;
2176 security_load_policycaps(state);
2177 selinux_mark_initialized(state);
2178 seqno = ++state->ss->latest_granting;
2179 selinux_complete_init();
2180 avc_ss_reset(state->avc, seqno);
2181 selnl_notify_policyload(seqno);
2182 selinux_status_update_policyload(state, seqno);
2183 selinux_netlbl_cache_invalidate();
2184 selinux_xfrm_notify_policyload();
2185 return 0;
2186 }
2187
2188 oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL);
2189 if (!oldpolicydb) {
2190 kfree(newsidtab);
2191 return -ENOMEM;
2192 }
2193 newpolicydb = oldpolicydb + 1;
2194
2195 rc = policydb_read(newpolicydb, fp);
2196 if (rc) {
2197 kfree(newsidtab);
2198 goto out;
2199 }
2200
2201 newpolicydb->len = len;
2202 /* If switching between different policy types, log MLS status */
2203 if (policydb->mls_enabled && !newpolicydb->mls_enabled)
2204 pr_info("SELinux: Disabling MLS support...\n");
2205 else if (!policydb->mls_enabled && newpolicydb->mls_enabled)
2206 pr_info("SELinux: Enabling MLS support...\n");
2207
2208 rc = policydb_load_isids(newpolicydb, newsidtab);
2209 if (rc) {
2210 pr_err("SELinux: unable to load the initial SIDs\n");
2211 policydb_destroy(newpolicydb);
2212 kfree(newsidtab);
2213 goto out;
2214 }
2215
2216 rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap);
2217 if (rc)
2218 goto err;
2219
2220 rc = security_preserve_bools(state, newpolicydb);
2221 if (rc) {
2222 pr_err("SELinux: unable to preserve booleans\n");
2223 goto err;
2224 }
2225
2226 oldsidtab = state->ss->sidtab;
2227
2228 /*
2229 * Convert the internal representations of contexts
2230 * in the new SID table.
2231 */
2232 args.state = state;
2233 args.oldp = policydb;
2234 args.newp = newpolicydb;
2235
2236 convert_params.func = convert_context;
2237 convert_params.args = &args;
2238 convert_params.target = newsidtab;
2239
2240 rc = sidtab_convert(oldsidtab, &convert_params);
2241 if (rc) {
2242 pr_err("SELinux: unable to convert the internal"
2243 " representation of contexts in the new SID"
2244 " table\n");
2245 goto err;
2246 }
2247
2248 /* Save the old policydb and SID table to free later. */
2249 memcpy(oldpolicydb, policydb, sizeof(*policydb));
2250
2251 /* Install the new policydb and SID table. */
2252 write_lock_irq(&state->ss->policy_rwlock);
2253 memcpy(policydb, newpolicydb, sizeof(*policydb));
2254 state->ss->sidtab = newsidtab;
2255 security_load_policycaps(state);
2256 oldmapping = state->ss->map.mapping;
2257 state->ss->map.mapping = newmap.mapping;
2258 state->ss->map.size = newmap.size;
2259 seqno = ++state->ss->latest_granting;
2260 write_unlock_irq(&state->ss->policy_rwlock);
2261
2262 /* Free the old policydb and SID table. */
2263 policydb_destroy(oldpolicydb);
2264 sidtab_destroy(oldsidtab);
2265 kfree(oldsidtab);
2266 kfree(oldmapping);
2267
2268 avc_ss_reset(state->avc, seqno);
2269 selnl_notify_policyload(seqno);
2270 selinux_status_update_policyload(state, seqno);
2271 selinux_netlbl_cache_invalidate();
2272 selinux_xfrm_notify_policyload();
2273
2274 rc = 0;
2275 goto out;
2276
2277err:
2278 kfree(newmap.mapping);
2279 sidtab_destroy(newsidtab);
2280 kfree(newsidtab);
2281 policydb_destroy(newpolicydb);
2282
2283out:
2284 kfree(oldpolicydb);
2285 return rc;
2286}
2287
2288size_t security_policydb_len(struct selinux_state *state)
2289{
2290 struct policydb *p = &state->ss->policydb;
2291 size_t len;
2292
2293 read_lock(&state->ss->policy_rwlock);
2294 len = p->len;
2295 read_unlock(&state->ss->policy_rwlock);
2296
2297 return len;
2298}
2299
2300/**
2301 * security_port_sid - Obtain the SID for a port.
2302 * @protocol: protocol number
2303 * @port: port number
2304 * @out_sid: security identifier
2305 */
2306int security_port_sid(struct selinux_state *state,
2307 u8 protocol, u16 port, u32 *out_sid)
2308{
2309 struct policydb *policydb;
2310 struct sidtab *sidtab;
2311 struct ocontext *c;
2312 int rc = 0;
2313
2314 read_lock(&state->ss->policy_rwlock);
2315
2316 policydb = &state->ss->policydb;
2317 sidtab = state->ss->sidtab;
2318
2319 c = policydb->ocontexts[OCON_PORT];
2320 while (c) {
2321 if (c->u.port.protocol == protocol &&
2322 c->u.port.low_port <= port &&
2323 c->u.port.high_port >= port)
2324 break;
2325 c = c->next;
2326 }
2327
2328 if (c) {
2329 if (!c->sid[0]) {
2330 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2331 &c->sid[0]);
2332 if (rc)
2333 goto out;
2334 }
2335 *out_sid = c->sid[0];
2336 } else {
2337 *out_sid = SECINITSID_PORT;
2338 }
2339
2340out:
2341 read_unlock(&state->ss->policy_rwlock);
2342 return rc;
2343}
2344
2345/**
2346 * security_pkey_sid - Obtain the SID for a pkey.
2347 * @subnet_prefix: Subnet Prefix
2348 * @pkey_num: pkey number
2349 * @out_sid: security identifier
2350 */
2351int security_ib_pkey_sid(struct selinux_state *state,
2352 u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2353{
2354 struct policydb *policydb;
2355 struct sidtab *sidtab;
2356 struct ocontext *c;
2357 int rc = 0;
2358
2359 read_lock(&state->ss->policy_rwlock);
2360
2361 policydb = &state->ss->policydb;
2362 sidtab = state->ss->sidtab;
2363
2364 c = policydb->ocontexts[OCON_IBPKEY];
2365 while (c) {
2366 if (c->u.ibpkey.low_pkey <= pkey_num &&
2367 c->u.ibpkey.high_pkey >= pkey_num &&
2368 c->u.ibpkey.subnet_prefix == subnet_prefix)
2369 break;
2370
2371 c = c->next;
2372 }
2373
2374 if (c) {
2375 if (!c->sid[0]) {
2376 rc = sidtab_context_to_sid(sidtab,
2377 &c->context[0],
2378 &c->sid[0]);
2379 if (rc)
2380 goto out;
2381 }
2382 *out_sid = c->sid[0];
2383 } else
2384 *out_sid = SECINITSID_UNLABELED;
2385
2386out:
2387 read_unlock(&state->ss->policy_rwlock);
2388 return rc;
2389}
2390
2391/**
2392 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2393 * @dev_name: device name
2394 * @port: port number
2395 * @out_sid: security identifier
2396 */
2397int security_ib_endport_sid(struct selinux_state *state,
2398 const char *dev_name, u8 port_num, u32 *out_sid)
2399{
2400 struct policydb *policydb;
2401 struct sidtab *sidtab;
2402 struct ocontext *c;
2403 int rc = 0;
2404
2405 read_lock(&state->ss->policy_rwlock);
2406
2407 policydb = &state->ss->policydb;
2408 sidtab = state->ss->sidtab;
2409
2410 c = policydb->ocontexts[OCON_IBENDPORT];
2411 while (c) {
2412 if (c->u.ibendport.port == port_num &&
2413 !strncmp(c->u.ibendport.dev_name,
2414 dev_name,
2415 IB_DEVICE_NAME_MAX))
2416 break;
2417
2418 c = c->next;
2419 }
2420
2421 if (c) {
2422 if (!c->sid[0]) {
2423 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2424 &c->sid[0]);
2425 if (rc)
2426 goto out;
2427 }
2428 *out_sid = c->sid[0];
2429 } else
2430 *out_sid = SECINITSID_UNLABELED;
2431
2432out:
2433 read_unlock(&state->ss->policy_rwlock);
2434 return rc;
2435}
2436
2437/**
2438 * security_netif_sid - Obtain the SID for a network interface.
2439 * @name: interface name
2440 * @if_sid: interface SID
2441 */
2442int security_netif_sid(struct selinux_state *state,
2443 char *name, u32 *if_sid)
2444{
2445 struct policydb *policydb;
2446 struct sidtab *sidtab;
2447 int rc = 0;
2448 struct ocontext *c;
2449
2450 read_lock(&state->ss->policy_rwlock);
2451
2452 policydb = &state->ss->policydb;
2453 sidtab = state->ss->sidtab;
2454
2455 c = policydb->ocontexts[OCON_NETIF];
2456 while (c) {
2457 if (strcmp(name, c->u.name) == 0)
2458 break;
2459 c = c->next;
2460 }
2461
2462 if (c) {
2463 if (!c->sid[0] || !c->sid[1]) {
2464 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2465 &c->sid[0]);
2466 if (rc)
2467 goto out;
2468 rc = sidtab_context_to_sid(sidtab, &c->context[1],
2469 &c->sid[1]);
2470 if (rc)
2471 goto out;
2472 }
2473 *if_sid = c->sid[0];
2474 } else
2475 *if_sid = SECINITSID_NETIF;
2476
2477out:
2478 read_unlock(&state->ss->policy_rwlock);
2479 return rc;
2480}
2481
2482static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2483{
2484 int i, fail = 0;
2485
2486 for (i = 0; i < 4; i++)
2487 if (addr[i] != (input[i] & mask[i])) {
2488 fail = 1;
2489 break;
2490 }
2491
2492 return !fail;
2493}
2494
2495/**
2496 * security_node_sid - Obtain the SID for a node (host).
2497 * @domain: communication domain aka address family
2498 * @addrp: address
2499 * @addrlen: address length in bytes
2500 * @out_sid: security identifier
2501 */
2502int security_node_sid(struct selinux_state *state,
2503 u16 domain,
2504 void *addrp,
2505 u32 addrlen,
2506 u32 *out_sid)
2507{
2508 struct policydb *policydb;
2509 struct sidtab *sidtab;
2510 int rc;
2511 struct ocontext *c;
2512
2513 read_lock(&state->ss->policy_rwlock);
2514
2515 policydb = &state->ss->policydb;
2516 sidtab = state->ss->sidtab;
2517
2518 switch (domain) {
2519 case AF_INET: {
2520 u32 addr;
2521
2522 rc = -EINVAL;
2523 if (addrlen != sizeof(u32))
2524 goto out;
2525
2526 addr = *((u32 *)addrp);
2527
2528 c = policydb->ocontexts[OCON_NODE];
2529 while (c) {
2530 if (c->u.node.addr == (addr & c->u.node.mask))
2531 break;
2532 c = c->next;
2533 }
2534 break;
2535 }
2536
2537 case AF_INET6:
2538 rc = -EINVAL;
2539 if (addrlen != sizeof(u64) * 2)
2540 goto out;
2541 c = policydb->ocontexts[OCON_NODE6];
2542 while (c) {
2543 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2544 c->u.node6.mask))
2545 break;
2546 c = c->next;
2547 }
2548 break;
2549
2550 default:
2551 rc = 0;
2552 *out_sid = SECINITSID_NODE;
2553 goto out;
2554 }
2555
2556 if (c) {
2557 if (!c->sid[0]) {
2558 rc = sidtab_context_to_sid(sidtab,
2559 &c->context[0],
2560 &c->sid[0]);
2561 if (rc)
2562 goto out;
2563 }
2564 *out_sid = c->sid[0];
2565 } else {
2566 *out_sid = SECINITSID_NODE;
2567 }
2568
2569 rc = 0;
2570out:
2571 read_unlock(&state->ss->policy_rwlock);
2572 return rc;
2573}
2574
2575#define SIDS_NEL 25
2576
2577/**
2578 * security_get_user_sids - Obtain reachable SIDs for a user.
2579 * @fromsid: starting SID
2580 * @username: username
2581 * @sids: array of reachable SIDs for user
2582 * @nel: number of elements in @sids
2583 *
2584 * Generate the set of SIDs for legal security contexts
2585 * for a given user that can be reached by @fromsid.
2586 * Set *@sids to point to a dynamically allocated
2587 * array containing the set of SIDs. Set *@nel to the
2588 * number of elements in the array.
2589 */
2590
2591int security_get_user_sids(struct selinux_state *state,
2592 u32 fromsid,
2593 char *username,
2594 u32 **sids,
2595 u32 *nel)
2596{
2597 struct policydb *policydb;
2598 struct sidtab *sidtab;
2599 struct context *fromcon, usercon;
2600 u32 *mysids = NULL, *mysids2, sid;
2601 u32 mynel = 0, maxnel = SIDS_NEL;
2602 struct user_datum *user;
2603 struct role_datum *role;
2604 struct ebitmap_node *rnode, *tnode;
2605 int rc = 0, i, j;
2606
2607 *sids = NULL;
2608 *nel = 0;
2609
2610 if (!selinux_initialized(state))
2611 goto out;
2612
2613 read_lock(&state->ss->policy_rwlock);
2614
2615 policydb = &state->ss->policydb;
2616 sidtab = state->ss->sidtab;
2617
2618 context_init(&usercon);
2619
2620 rc = -EINVAL;
2621 fromcon = sidtab_search(sidtab, fromsid);
2622 if (!fromcon)
2623 goto out_unlock;
2624
2625 rc = -EINVAL;
2626 user = symtab_search(&policydb->p_users, username);
2627 if (!user)
2628 goto out_unlock;
2629
2630 usercon.user = user->value;
2631
2632 rc = -ENOMEM;
2633 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2634 if (!mysids)
2635 goto out_unlock;
2636
2637 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2638 role = policydb->role_val_to_struct[i];
2639 usercon.role = i + 1;
2640 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2641 usercon.type = j + 1;
2642
2643 if (mls_setup_user_range(policydb, fromcon, user,
2644 &usercon))
2645 continue;
2646
2647 rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2648 if (rc)
2649 goto out_unlock;
2650 if (mynel < maxnel) {
2651 mysids[mynel++] = sid;
2652 } else {
2653 rc = -ENOMEM;
2654 maxnel += SIDS_NEL;
2655 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2656 if (!mysids2)
2657 goto out_unlock;
2658 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2659 kfree(mysids);
2660 mysids = mysids2;
2661 mysids[mynel++] = sid;
2662 }
2663 }
2664 }
2665 rc = 0;
2666out_unlock:
2667 read_unlock(&state->ss->policy_rwlock);
2668 if (rc || !mynel) {
2669 kfree(mysids);
2670 goto out;
2671 }
2672
2673 rc = -ENOMEM;
2674 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2675 if (!mysids2) {
2676 kfree(mysids);
2677 goto out;
2678 }
2679 for (i = 0, j = 0; i < mynel; i++) {
2680 struct av_decision dummy_avd;
2681 rc = avc_has_perm_noaudit(state,
2682 fromsid, mysids[i],
2683 SECCLASS_PROCESS, /* kernel value */
2684 PROCESS__TRANSITION, AVC_STRICT,
2685 &dummy_avd);
2686 if (!rc)
2687 mysids2[j++] = mysids[i];
2688 cond_resched();
2689 }
2690 rc = 0;
2691 kfree(mysids);
2692 *sids = mysids2;
2693 *nel = j;
2694out:
2695 return rc;
2696}
2697
2698/**
2699 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2700 * @fstype: filesystem type
2701 * @path: path from root of mount
2702 * @sclass: file security class
2703 * @sid: SID for path
2704 *
2705 * Obtain a SID to use for a file in a filesystem that
2706 * cannot support xattr or use a fixed labeling behavior like
2707 * transition SIDs or task SIDs.
2708 *
2709 * The caller must acquire the policy_rwlock before calling this function.
2710 */
2711static inline int __security_genfs_sid(struct selinux_state *state,
2712 const char *fstype,
2713 char *path,
2714 u16 orig_sclass,
2715 u32 *sid)
2716{
2717 struct policydb *policydb = &state->ss->policydb;
2718 struct sidtab *sidtab = state->ss->sidtab;
2719 int len;
2720 u16 sclass;
2721 struct genfs *genfs;
2722 struct ocontext *c;
2723 int rc, cmp = 0;
2724
2725 while (path[0] == '/' && path[1] == '/')
2726 path++;
2727
2728 sclass = unmap_class(&state->ss->map, orig_sclass);
2729 *sid = SECINITSID_UNLABELED;
2730
2731 for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2732 cmp = strcmp(fstype, genfs->fstype);
2733 if (cmp <= 0)
2734 break;
2735 }
2736
2737 rc = -ENOENT;
2738 if (!genfs || cmp)
2739 goto out;
2740
2741 for (c = genfs->head; c; c = c->next) {
2742 len = strlen(c->u.name);
2743 if ((!c->v.sclass || sclass == c->v.sclass) &&
2744 (strncmp(c->u.name, path, len) == 0))
2745 break;
2746 }
2747
2748 rc = -ENOENT;
2749 if (!c)
2750 goto out;
2751
2752 if (!c->sid[0]) {
2753 rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]);
2754 if (rc)
2755 goto out;
2756 }
2757
2758 *sid = c->sid[0];
2759 rc = 0;
2760out:
2761 return rc;
2762}
2763
2764/**
2765 * security_genfs_sid - Obtain a SID for a file in a filesystem
2766 * @fstype: filesystem type
2767 * @path: path from root of mount
2768 * @sclass: file security class
2769 * @sid: SID for path
2770 *
2771 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2772 * it afterward.
2773 */
2774int security_genfs_sid(struct selinux_state *state,
2775 const char *fstype,
2776 char *path,
2777 u16 orig_sclass,
2778 u32 *sid)
2779{
2780 int retval;
2781
2782 read_lock(&state->ss->policy_rwlock);
2783 retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid);
2784 read_unlock(&state->ss->policy_rwlock);
2785 return retval;
2786}
2787
2788/**
2789 * security_fs_use - Determine how to handle labeling for a filesystem.
2790 * @sb: superblock in question
2791 */
2792int security_fs_use(struct selinux_state *state, struct super_block *sb)
2793{
2794 struct policydb *policydb;
2795 struct sidtab *sidtab;
2796 int rc = 0;
2797 struct ocontext *c;
2798 struct superblock_security_struct *sbsec = sb->s_security;
2799 const char *fstype = sb->s_type->name;
2800
2801 read_lock(&state->ss->policy_rwlock);
2802
2803 policydb = &state->ss->policydb;
2804 sidtab = state->ss->sidtab;
2805
2806 c = policydb->ocontexts[OCON_FSUSE];
2807 while (c) {
2808 if (strcmp(fstype, c->u.name) == 0)
2809 break;
2810 c = c->next;
2811 }
2812
2813 if (c) {
2814 sbsec->behavior = c->v.behavior;
2815 if (!c->sid[0]) {
2816 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2817 &c->sid[0]);
2818 if (rc)
2819 goto out;
2820 }
2821 sbsec->sid = c->sid[0];
2822 } else {
2823 rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR,
2824 &sbsec->sid);
2825 if (rc) {
2826 sbsec->behavior = SECURITY_FS_USE_NONE;
2827 rc = 0;
2828 } else {
2829 sbsec->behavior = SECURITY_FS_USE_GENFS;
2830 }
2831 }
2832
2833out:
2834 read_unlock(&state->ss->policy_rwlock);
2835 return rc;
2836}
2837
2838int security_get_bools(struct selinux_state *state,
2839 u32 *len, char ***names, int **values)
2840{
2841 struct policydb *policydb;
2842 u32 i;
2843 int rc;
2844
2845 if (!selinux_initialized(state)) {
2846 *len = 0;
2847 *names = NULL;
2848 *values = NULL;
2849 return 0;
2850 }
2851
2852 read_lock(&state->ss->policy_rwlock);
2853
2854 policydb = &state->ss->policydb;
2855
2856 *names = NULL;
2857 *values = NULL;
2858
2859 rc = 0;
2860 *len = policydb->p_bools.nprim;
2861 if (!*len)
2862 goto out;
2863
2864 rc = -ENOMEM;
2865 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2866 if (!*names)
2867 goto err;
2868
2869 rc = -ENOMEM;
2870 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2871 if (!*values)
2872 goto err;
2873
2874 for (i = 0; i < *len; i++) {
2875 (*values)[i] = policydb->bool_val_to_struct[i]->state;
2876
2877 rc = -ENOMEM;
2878 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
2879 GFP_ATOMIC);
2880 if (!(*names)[i])
2881 goto err;
2882 }
2883 rc = 0;
2884out:
2885 read_unlock(&state->ss->policy_rwlock);
2886 return rc;
2887err:
2888 if (*names) {
2889 for (i = 0; i < *len; i++)
2890 kfree((*names)[i]);
2891 kfree(*names);
2892 }
2893 kfree(*values);
2894 *len = 0;
2895 *names = NULL;
2896 *values = NULL;
2897 goto out;
2898}
2899
2900
2901int security_set_bools(struct selinux_state *state, u32 len, int *values)
2902{
2903 struct policydb *policydb;
2904 int rc;
2905 u32 i, lenp, seqno = 0;
2906
2907 write_lock_irq(&state->ss->policy_rwlock);
2908
2909 policydb = &state->ss->policydb;
2910
2911 rc = -EFAULT;
2912 lenp = policydb->p_bools.nprim;
2913 if (len != lenp)
2914 goto out;
2915
2916 for (i = 0; i < len; i++) {
2917 if (!!values[i] != policydb->bool_val_to_struct[i]->state) {
2918 audit_log(audit_context(), GFP_ATOMIC,
2919 AUDIT_MAC_CONFIG_CHANGE,
2920 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2921 sym_name(policydb, SYM_BOOLS, i),
2922 !!values[i],
2923 policydb->bool_val_to_struct[i]->state,
2924 from_kuid(&init_user_ns, audit_get_loginuid(current)),
2925 audit_get_sessionid(current));
2926 }
2927 if (values[i])
2928 policydb->bool_val_to_struct[i]->state = 1;
2929 else
2930 policydb->bool_val_to_struct[i]->state = 0;
2931 }
2932
2933 evaluate_cond_nodes(policydb);
2934
2935 seqno = ++state->ss->latest_granting;
2936 rc = 0;
2937out:
2938 write_unlock_irq(&state->ss->policy_rwlock);
2939 if (!rc) {
2940 avc_ss_reset(state->avc, seqno);
2941 selnl_notify_policyload(seqno);
2942 selinux_status_update_policyload(state, seqno);
2943 selinux_xfrm_notify_policyload();
2944 }
2945 return rc;
2946}
2947
2948int security_get_bool_value(struct selinux_state *state,
2949 u32 index)
2950{
2951 struct policydb *policydb;
2952 int rc;
2953 u32 len;
2954
2955 read_lock(&state->ss->policy_rwlock);
2956
2957 policydb = &state->ss->policydb;
2958
2959 rc = -EFAULT;
2960 len = policydb->p_bools.nprim;
2961 if (index >= len)
2962 goto out;
2963
2964 rc = policydb->bool_val_to_struct[index]->state;
2965out:
2966 read_unlock(&state->ss->policy_rwlock);
2967 return rc;
2968}
2969
2970static int security_preserve_bools(struct selinux_state *state,
2971 struct policydb *policydb)
2972{
2973 int rc, *bvalues = NULL;
2974 char **bnames = NULL;
2975 struct cond_bool_datum *booldatum;
2976 u32 i, nbools = 0;
2977
2978 rc = security_get_bools(state, &nbools, &bnames, &bvalues);
2979 if (rc)
2980 goto out;
2981 for (i = 0; i < nbools; i++) {
2982 booldatum = symtab_search(&policydb->p_bools, bnames[i]);
2983 if (booldatum)
2984 booldatum->state = bvalues[i];
2985 }
2986 evaluate_cond_nodes(policydb);
2987
2988out:
2989 if (bnames) {
2990 for (i = 0; i < nbools; i++)
2991 kfree(bnames[i]);
2992 }
2993 kfree(bnames);
2994 kfree(bvalues);
2995 return rc;
2996}
2997
2998/*
2999 * security_sid_mls_copy() - computes a new sid based on the given
3000 * sid and the mls portion of mls_sid.
3001 */
3002int security_sid_mls_copy(struct selinux_state *state,
3003 u32 sid, u32 mls_sid, u32 *new_sid)
3004{
3005 struct policydb *policydb = &state->ss->policydb;
3006 struct sidtab *sidtab = state->ss->sidtab;
3007 struct context *context1;
3008 struct context *context2;
3009 struct context newcon;
3010 char *s;
3011 u32 len;
3012 int rc;
3013
3014 rc = 0;
3015 if (!selinux_initialized(state) || !policydb->mls_enabled) {
3016 *new_sid = sid;
3017 goto out;
3018 }
3019
3020 context_init(&newcon);
3021
3022 read_lock(&state->ss->policy_rwlock);
3023
3024 rc = -EINVAL;
3025 context1 = sidtab_search(sidtab, sid);
3026 if (!context1) {
3027 pr_err("SELinux: %s: unrecognized SID %d\n",
3028 __func__, sid);
3029 goto out_unlock;
3030 }
3031
3032 rc = -EINVAL;
3033 context2 = sidtab_search(sidtab, mls_sid);
3034 if (!context2) {
3035 pr_err("SELinux: %s: unrecognized SID %d\n",
3036 __func__, mls_sid);
3037 goto out_unlock;
3038 }
3039
3040 newcon.user = context1->user;
3041 newcon.role = context1->role;
3042 newcon.type = context1->type;
3043 rc = mls_context_cpy(&newcon, context2);
3044 if (rc)
3045 goto out_unlock;
3046
3047 /* Check the validity of the new context. */
3048 if (!policydb_context_isvalid(policydb, &newcon)) {
3049 rc = convert_context_handle_invalid_context(state, &newcon);
3050 if (rc) {
3051 if (!context_struct_to_string(policydb, &newcon, &s,
3052 &len)) {
3053 struct audit_buffer *ab;
3054
3055 ab = audit_log_start(audit_context(),
3056 GFP_ATOMIC,
3057 AUDIT_SELINUX_ERR);
3058 audit_log_format(ab,
3059 "op=security_sid_mls_copy invalid_context=");
3060 /* don't record NUL with untrusted strings */
3061 audit_log_n_untrustedstring(ab, s, len - 1);
3062 audit_log_end(ab);
3063 kfree(s);
3064 }
3065 goto out_unlock;
3066 }
3067 }
3068 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3069out_unlock:
3070 read_unlock(&state->ss->policy_rwlock);
3071 context_destroy(&newcon);
3072out:
3073 return rc;
3074}
3075
3076/**
3077 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3078 * @nlbl_sid: NetLabel SID
3079 * @nlbl_type: NetLabel labeling protocol type
3080 * @xfrm_sid: XFRM SID
3081 *
3082 * Description:
3083 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3084 * resolved into a single SID it is returned via @peer_sid and the function
3085 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3086 * returns a negative value. A table summarizing the behavior is below:
3087 *
3088 * | function return | @sid
3089 * ------------------------------+-----------------+-----------------
3090 * no peer labels | 0 | SECSID_NULL
3091 * single peer label | 0 | <peer_label>
3092 * multiple, consistent labels | 0 | <peer_label>
3093 * multiple, inconsistent labels | -<errno> | SECSID_NULL
3094 *
3095 */
3096int security_net_peersid_resolve(struct selinux_state *state,
3097 u32 nlbl_sid, u32 nlbl_type,
3098 u32 xfrm_sid,
3099 u32 *peer_sid)
3100{
3101 struct policydb *policydb = &state->ss->policydb;
3102 struct sidtab *sidtab = state->ss->sidtab;
3103 int rc;
3104 struct context *nlbl_ctx;
3105 struct context *xfrm_ctx;
3106
3107 *peer_sid = SECSID_NULL;
3108
3109 /* handle the common (which also happens to be the set of easy) cases
3110 * right away, these two if statements catch everything involving a
3111 * single or absent peer SID/label */
3112 if (xfrm_sid == SECSID_NULL) {
3113 *peer_sid = nlbl_sid;
3114 return 0;
3115 }
3116 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3117 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3118 * is present */
3119 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3120 *peer_sid = xfrm_sid;
3121 return 0;
3122 }
3123
3124 /*
3125 * We don't need to check initialized here since the only way both
3126 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3127 * security server was initialized and state->initialized was true.
3128 */
3129 if (!policydb->mls_enabled)
3130 return 0;
3131
3132 read_lock(&state->ss->policy_rwlock);
3133
3134 rc = -EINVAL;
3135 nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3136 if (!nlbl_ctx) {
3137 pr_err("SELinux: %s: unrecognized SID %d\n",
3138 __func__, nlbl_sid);
3139 goto out;
3140 }
3141 rc = -EINVAL;
3142 xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3143 if (!xfrm_ctx) {
3144 pr_err("SELinux: %s: unrecognized SID %d\n",
3145 __func__, xfrm_sid);
3146 goto out;
3147 }
3148 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3149 if (rc)
3150 goto out;
3151
3152 /* at present NetLabel SIDs/labels really only carry MLS
3153 * information so if the MLS portion of the NetLabel SID
3154 * matches the MLS portion of the labeled XFRM SID/label
3155 * then pass along the XFRM SID as it is the most
3156 * expressive */
3157 *peer_sid = xfrm_sid;
3158out:
3159 read_unlock(&state->ss->policy_rwlock);
3160 return rc;
3161}
3162
3163static int get_classes_callback(void *k, void *d, void *args)
3164{
3165 struct class_datum *datum = d;
3166 char *name = k, **classes = args;
3167 int value = datum->value - 1;
3168
3169 classes[value] = kstrdup(name, GFP_ATOMIC);
3170 if (!classes[value])
3171 return -ENOMEM;
3172
3173 return 0;
3174}
3175
3176int security_get_classes(struct selinux_state *state,
3177 char ***classes, int *nclasses)
3178{
3179 struct policydb *policydb = &state->ss->policydb;
3180 int rc;
3181
3182 if (!selinux_initialized(state)) {
3183 *nclasses = 0;
3184 *classes = NULL;
3185 return 0;
3186 }
3187
3188 read_lock(&state->ss->policy_rwlock);
3189
3190 rc = -ENOMEM;
3191 *nclasses = policydb->p_classes.nprim;
3192 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3193 if (!*classes)
3194 goto out;
3195
3196 rc = hashtab_map(&policydb->p_classes.table, get_classes_callback,
3197 *classes);
3198 if (rc) {
3199 int i;
3200 for (i = 0; i < *nclasses; i++)
3201 kfree((*classes)[i]);
3202 kfree(*classes);
3203 }
3204
3205out:
3206 read_unlock(&state->ss->policy_rwlock);
3207 return rc;
3208}
3209
3210static int get_permissions_callback(void *k, void *d, void *args)
3211{
3212 struct perm_datum *datum = d;
3213 char *name = k, **perms = args;
3214 int value = datum->value - 1;
3215
3216 perms[value] = kstrdup(name, GFP_ATOMIC);
3217 if (!perms[value])
3218 return -ENOMEM;
3219
3220 return 0;
3221}
3222
3223int security_get_permissions(struct selinux_state *state,
3224 char *class, char ***perms, int *nperms)
3225{
3226 struct policydb *policydb = &state->ss->policydb;
3227 int rc, i;
3228 struct class_datum *match;
3229
3230 read_lock(&state->ss->policy_rwlock);
3231
3232 rc = -EINVAL;
3233 match = symtab_search(&policydb->p_classes, class);
3234 if (!match) {
3235 pr_err("SELinux: %s: unrecognized class %s\n",
3236 __func__, class);
3237 goto out;
3238 }
3239
3240 rc = -ENOMEM;
3241 *nperms = match->permissions.nprim;
3242 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3243 if (!*perms)
3244 goto out;
3245
3246 if (match->comdatum) {
3247 rc = hashtab_map(&match->comdatum->permissions.table,
3248 get_permissions_callback, *perms);
3249 if (rc)
3250 goto err;
3251 }
3252
3253 rc = hashtab_map(&match->permissions.table, get_permissions_callback,
3254 *perms);
3255 if (rc)
3256 goto err;
3257
3258out:
3259 read_unlock(&state->ss->policy_rwlock);
3260 return rc;
3261
3262err:
3263 read_unlock(&state->ss->policy_rwlock);
3264 for (i = 0; i < *nperms; i++)
3265 kfree((*perms)[i]);
3266 kfree(*perms);
3267 return rc;
3268}
3269
3270int security_get_reject_unknown(struct selinux_state *state)
3271{
3272 return state->ss->policydb.reject_unknown;
3273}
3274
3275int security_get_allow_unknown(struct selinux_state *state)
3276{
3277 return state->ss->policydb.allow_unknown;
3278}
3279
3280/**
3281 * security_policycap_supported - Check for a specific policy capability
3282 * @req_cap: capability
3283 *
3284 * Description:
3285 * This function queries the currently loaded policy to see if it supports the
3286 * capability specified by @req_cap. Returns true (1) if the capability is
3287 * supported, false (0) if it isn't supported.
3288 *
3289 */
3290int security_policycap_supported(struct selinux_state *state,
3291 unsigned int req_cap)
3292{
3293 struct policydb *policydb = &state->ss->policydb;
3294 int rc;
3295
3296 read_lock(&state->ss->policy_rwlock);
3297 rc = ebitmap_get_bit(&policydb->policycaps, req_cap);
3298 read_unlock(&state->ss->policy_rwlock);
3299
3300 return rc;
3301}
3302
3303struct selinux_audit_rule {
3304 u32 au_seqno;
3305 struct context au_ctxt;
3306};
3307
3308void selinux_audit_rule_free(void *vrule)
3309{
3310 struct selinux_audit_rule *rule = vrule;
3311
3312 if (rule) {
3313 context_destroy(&rule->au_ctxt);
3314 kfree(rule);
3315 }
3316}
3317
3318int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3319{
3320 struct selinux_state *state = &selinux_state;
3321 struct policydb *policydb = &state->ss->policydb;
3322 struct selinux_audit_rule *tmprule;
3323 struct role_datum *roledatum;
3324 struct type_datum *typedatum;
3325 struct user_datum *userdatum;
3326 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3327 int rc = 0;
3328
3329 *rule = NULL;
3330
3331 if (!selinux_initialized(state))
3332 return -EOPNOTSUPP;
3333
3334 switch (field) {
3335 case AUDIT_SUBJ_USER:
3336 case AUDIT_SUBJ_ROLE:
3337 case AUDIT_SUBJ_TYPE:
3338 case AUDIT_OBJ_USER:
3339 case AUDIT_OBJ_ROLE:
3340 case AUDIT_OBJ_TYPE:
3341 /* only 'equals' and 'not equals' fit user, role, and type */
3342 if (op != Audit_equal && op != Audit_not_equal)
3343 return -EINVAL;
3344 break;
3345 case AUDIT_SUBJ_SEN:
3346 case AUDIT_SUBJ_CLR:
3347 case AUDIT_OBJ_LEV_LOW:
3348 case AUDIT_OBJ_LEV_HIGH:
3349 /* we do not allow a range, indicated by the presence of '-' */
3350 if (strchr(rulestr, '-'))
3351 return -EINVAL;
3352 break;
3353 default:
3354 /* only the above fields are valid */
3355 return -EINVAL;
3356 }
3357
3358 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3359 if (!tmprule)
3360 return -ENOMEM;
3361
3362 context_init(&tmprule->au_ctxt);
3363
3364 read_lock(&state->ss->policy_rwlock);
3365
3366 tmprule->au_seqno = state->ss->latest_granting;
3367
3368 switch (field) {
3369 case AUDIT_SUBJ_USER:
3370 case AUDIT_OBJ_USER:
3371 rc = -EINVAL;
3372 userdatum = symtab_search(&policydb->p_users, rulestr);
3373 if (!userdatum)
3374 goto out;
3375 tmprule->au_ctxt.user = userdatum->value;
3376 break;
3377 case AUDIT_SUBJ_ROLE:
3378 case AUDIT_OBJ_ROLE:
3379 rc = -EINVAL;
3380 roledatum = symtab_search(&policydb->p_roles, rulestr);
3381 if (!roledatum)
3382 goto out;
3383 tmprule->au_ctxt.role = roledatum->value;
3384 break;
3385 case AUDIT_SUBJ_TYPE:
3386 case AUDIT_OBJ_TYPE:
3387 rc = -EINVAL;
3388 typedatum = symtab_search(&policydb->p_types, rulestr);
3389 if (!typedatum)
3390 goto out;
3391 tmprule->au_ctxt.type = typedatum->value;
3392 break;
3393 case AUDIT_SUBJ_SEN:
3394 case AUDIT_SUBJ_CLR:
3395 case AUDIT_OBJ_LEV_LOW:
3396 case AUDIT_OBJ_LEV_HIGH:
3397 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3398 GFP_ATOMIC);
3399 if (rc)
3400 goto out;
3401 break;
3402 }
3403 rc = 0;
3404out:
3405 read_unlock(&state->ss->policy_rwlock);
3406
3407 if (rc) {
3408 selinux_audit_rule_free(tmprule);
3409 tmprule = NULL;
3410 }
3411
3412 *rule = tmprule;
3413
3414 return rc;
3415}
3416
3417/* Check to see if the rule contains any selinux fields */
3418int selinux_audit_rule_known(struct audit_krule *rule)
3419{
3420 int i;
3421
3422 for (i = 0; i < rule->field_count; i++) {
3423 struct audit_field *f = &rule->fields[i];
3424 switch (f->type) {
3425 case AUDIT_SUBJ_USER:
3426 case AUDIT_SUBJ_ROLE:
3427 case AUDIT_SUBJ_TYPE:
3428 case AUDIT_SUBJ_SEN:
3429 case AUDIT_SUBJ_CLR:
3430 case AUDIT_OBJ_USER:
3431 case AUDIT_OBJ_ROLE:
3432 case AUDIT_OBJ_TYPE:
3433 case AUDIT_OBJ_LEV_LOW:
3434 case AUDIT_OBJ_LEV_HIGH:
3435 return 1;
3436 }
3437 }
3438
3439 return 0;
3440}
3441
3442int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule)
3443{
3444 struct selinux_state *state = &selinux_state;
3445 struct context *ctxt;
3446 struct mls_level *level;
3447 struct selinux_audit_rule *rule = vrule;
3448 int match = 0;
3449
3450 if (unlikely(!rule)) {
3451 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3452 return -ENOENT;
3453 }
3454
3455 read_lock(&state->ss->policy_rwlock);
3456
3457 if (rule->au_seqno < state->ss->latest_granting) {
3458 match = -ESTALE;
3459 goto out;
3460 }
3461
3462 ctxt = sidtab_search(state->ss->sidtab, sid);
3463 if (unlikely(!ctxt)) {
3464 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3465 sid);
3466 match = -ENOENT;
3467 goto out;
3468 }
3469
3470 /* a field/op pair that is not caught here will simply fall through
3471 without a match */
3472 switch (field) {
3473 case AUDIT_SUBJ_USER:
3474 case AUDIT_OBJ_USER:
3475 switch (op) {
3476 case Audit_equal:
3477 match = (ctxt->user == rule->au_ctxt.user);
3478 break;
3479 case Audit_not_equal:
3480 match = (ctxt->user != rule->au_ctxt.user);
3481 break;
3482 }
3483 break;
3484 case AUDIT_SUBJ_ROLE:
3485 case AUDIT_OBJ_ROLE:
3486 switch (op) {
3487 case Audit_equal:
3488 match = (ctxt->role == rule->au_ctxt.role);
3489 break;
3490 case Audit_not_equal:
3491 match = (ctxt->role != rule->au_ctxt.role);
3492 break;
3493 }
3494 break;
3495 case AUDIT_SUBJ_TYPE:
3496 case AUDIT_OBJ_TYPE:
3497 switch (op) {
3498 case Audit_equal:
3499 match = (ctxt->type == rule->au_ctxt.type);
3500 break;
3501 case Audit_not_equal:
3502 match = (ctxt->type != rule->au_ctxt.type);
3503 break;
3504 }
3505 break;
3506 case AUDIT_SUBJ_SEN:
3507 case AUDIT_SUBJ_CLR:
3508 case AUDIT_OBJ_LEV_LOW:
3509 case AUDIT_OBJ_LEV_HIGH:
3510 level = ((field == AUDIT_SUBJ_SEN ||
3511 field == AUDIT_OBJ_LEV_LOW) ?
3512 &ctxt->range.level[0] : &ctxt->range.level[1]);
3513 switch (op) {
3514 case Audit_equal:
3515 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3516 level);
3517 break;
3518 case Audit_not_equal:
3519 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3520 level);
3521 break;
3522 case Audit_lt:
3523 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3524 level) &&
3525 !mls_level_eq(&rule->au_ctxt.range.level[0],
3526 level));
3527 break;
3528 case Audit_le:
3529 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3530 level);
3531 break;
3532 case Audit_gt:
3533 match = (mls_level_dom(level,
3534 &rule->au_ctxt.range.level[0]) &&
3535 !mls_level_eq(level,
3536 &rule->au_ctxt.range.level[0]));
3537 break;
3538 case Audit_ge:
3539 match = mls_level_dom(level,
3540 &rule->au_ctxt.range.level[0]);
3541 break;
3542 }
3543 }
3544
3545out:
3546 read_unlock(&state->ss->policy_rwlock);
3547 return match;
3548}
3549
3550static int (*aurule_callback)(void) = audit_update_lsm_rules;
3551
3552static int aurule_avc_callback(u32 event)
3553{
3554 int err = 0;
3555
3556 if (event == AVC_CALLBACK_RESET && aurule_callback)
3557 err = aurule_callback();
3558 return err;
3559}
3560
3561static int __init aurule_init(void)
3562{
3563 int err;
3564
3565 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3566 if (err)
3567 panic("avc_add_callback() failed, error %d\n", err);
3568
3569 return err;
3570}
3571__initcall(aurule_init);
3572
3573#ifdef CONFIG_NETLABEL
3574/**
3575 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3576 * @secattr: the NetLabel packet security attributes
3577 * @sid: the SELinux SID
3578 *
3579 * Description:
3580 * Attempt to cache the context in @ctx, which was derived from the packet in
3581 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3582 * already been initialized.
3583 *
3584 */
3585static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3586 u32 sid)
3587{
3588 u32 *sid_cache;
3589
3590 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3591 if (sid_cache == NULL)
3592 return;
3593 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3594 if (secattr->cache == NULL) {
3595 kfree(sid_cache);
3596 return;
3597 }
3598
3599 *sid_cache = sid;
3600 secattr->cache->free = kfree;
3601 secattr->cache->data = sid_cache;
3602 secattr->flags |= NETLBL_SECATTR_CACHE;
3603}
3604
3605/**
3606 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3607 * @secattr: the NetLabel packet security attributes
3608 * @sid: the SELinux SID
3609 *
3610 * Description:
3611 * Convert the given NetLabel security attributes in @secattr into a
3612 * SELinux SID. If the @secattr field does not contain a full SELinux
3613 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3614 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3615 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3616 * conversion for future lookups. Returns zero on success, negative values on
3617 * failure.
3618 *
3619 */
3620int security_netlbl_secattr_to_sid(struct selinux_state *state,
3621 struct netlbl_lsm_secattr *secattr,
3622 u32 *sid)
3623{
3624 struct policydb *policydb = &state->ss->policydb;
3625 struct sidtab *sidtab = state->ss->sidtab;
3626 int rc;
3627 struct context *ctx;
3628 struct context ctx_new;
3629
3630 if (!selinux_initialized(state)) {
3631 *sid = SECSID_NULL;
3632 return 0;
3633 }
3634
3635 read_lock(&state->ss->policy_rwlock);
3636
3637 if (secattr->flags & NETLBL_SECATTR_CACHE)
3638 *sid = *(u32 *)secattr->cache->data;
3639 else if (secattr->flags & NETLBL_SECATTR_SECID)
3640 *sid = secattr->attr.secid;
3641 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3642 rc = -EIDRM;
3643 ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3644 if (ctx == NULL)
3645 goto out;
3646
3647 context_init(&ctx_new);
3648 ctx_new.user = ctx->user;
3649 ctx_new.role = ctx->role;
3650 ctx_new.type = ctx->type;
3651 mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3652 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3653 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3654 if (rc)
3655 goto out;
3656 }
3657 rc = -EIDRM;
3658 if (!mls_context_isvalid(policydb, &ctx_new))
3659 goto out_free;
3660
3661 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3662 if (rc)
3663 goto out_free;
3664
3665 security_netlbl_cache_add(secattr, *sid);
3666
3667 ebitmap_destroy(&ctx_new.range.level[0].cat);
3668 } else
3669 *sid = SECSID_NULL;
3670
3671 read_unlock(&state->ss->policy_rwlock);
3672 return 0;
3673out_free:
3674 ebitmap_destroy(&ctx_new.range.level[0].cat);
3675out:
3676 read_unlock(&state->ss->policy_rwlock);
3677 return rc;
3678}
3679
3680/**
3681 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3682 * @sid: the SELinux SID
3683 * @secattr: the NetLabel packet security attributes
3684 *
3685 * Description:
3686 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3687 * Returns zero on success, negative values on failure.
3688 *
3689 */
3690int security_netlbl_sid_to_secattr(struct selinux_state *state,
3691 u32 sid, struct netlbl_lsm_secattr *secattr)
3692{
3693 struct policydb *policydb = &state->ss->policydb;
3694 int rc;
3695 struct context *ctx;
3696
3697 if (!selinux_initialized(state))
3698 return 0;
3699
3700 read_lock(&state->ss->policy_rwlock);
3701
3702 rc = -ENOENT;
3703 ctx = sidtab_search(state->ss->sidtab, sid);
3704 if (ctx == NULL)
3705 goto out;
3706
3707 rc = -ENOMEM;
3708 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3709 GFP_ATOMIC);
3710 if (secattr->domain == NULL)
3711 goto out;
3712
3713 secattr->attr.secid = sid;
3714 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3715 mls_export_netlbl_lvl(policydb, ctx, secattr);
3716 rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3717out:
3718 read_unlock(&state->ss->policy_rwlock);
3719 return rc;
3720}
3721#endif /* CONFIG_NETLABEL */
3722
3723/**
3724 * security_read_policy - read the policy.
3725 * @data: binary policy data
3726 * @len: length of data in bytes
3727 *
3728 */
3729int security_read_policy(struct selinux_state *state,
3730 void **data, size_t *len)
3731{
3732 struct policydb *policydb = &state->ss->policydb;
3733 int rc;
3734 struct policy_file fp;
3735
3736 if (!selinux_initialized(state))
3737 return -EINVAL;
3738
3739 *len = security_policydb_len(state);
3740
3741 *data = vmalloc_user(*len);
3742 if (!*data)
3743 return -ENOMEM;
3744
3745 fp.data = *data;
3746 fp.len = *len;
3747
3748 read_lock(&state->ss->policy_rwlock);
3749 rc = policydb_write(policydb, &fp);
3750 read_unlock(&state->ss->policy_rwlock);
3751
3752 if (rc)
3753 return rc;
3754
3755 *len = (unsigned long)fp.data - (unsigned long)*data;
3756 return 0;
3757
3758}