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