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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 <linux/lsm_hooks.h>
51#include <net/netlabel.h>
52
53#include "flask.h"
54#include "avc.h"
55#include "avc_ss.h"
56#include "security.h"
57#include "context.h"
58#include "policydb.h"
59#include "sidtab.h"
60#include "services.h"
61#include "conditional.h"
62#include "mls.h"
63#include "objsec.h"
64#include "netlabel.h"
65#include "xfrm.h"
66#include "ebitmap.h"
67#include "audit.h"
68#include "policycap_names.h"
69#include "ima.h"
70
71struct convert_context_args {
72 struct selinux_state *state;
73 struct policydb *oldp;
74 struct policydb *newp;
75};
76
77struct selinux_policy_convert_data {
78 struct convert_context_args args;
79 struct sidtab_convert_params sidtab_params;
80};
81
82/* Forward declaration. */
83static int context_struct_to_string(struct policydb *policydb,
84 struct context *context,
85 char **scontext,
86 u32 *scontext_len);
87
88static int sidtab_entry_to_string(struct policydb *policydb,
89 struct sidtab *sidtab,
90 struct sidtab_entry *entry,
91 char **scontext,
92 u32 *scontext_len);
93
94static void context_struct_compute_av(struct policydb *policydb,
95 struct context *scontext,
96 struct context *tcontext,
97 u16 tclass,
98 struct av_decision *avd,
99 struct extended_perms *xperms);
100
101static int selinux_set_mapping(struct policydb *pol,
102 struct security_class_mapping *map,
103 struct selinux_map *out_map)
104{
105 u16 i, j;
106 unsigned k;
107 bool print_unknown_handle = false;
108
109 /* Find number of classes in the input mapping */
110 if (!map)
111 return -EINVAL;
112 i = 0;
113 while (map[i].name)
114 i++;
115
116 /* Allocate space for the class records, plus one for class zero */
117 out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC);
118 if (!out_map->mapping)
119 return -ENOMEM;
120
121 /* Store the raw class and permission values */
122 j = 0;
123 while (map[j].name) {
124 struct security_class_mapping *p_in = map + (j++);
125 struct selinux_mapping *p_out = out_map->mapping + j;
126
127 /* An empty class string skips ahead */
128 if (!strcmp(p_in->name, "")) {
129 p_out->num_perms = 0;
130 continue;
131 }
132
133 p_out->value = string_to_security_class(pol, p_in->name);
134 if (!p_out->value) {
135 pr_info("SELinux: Class %s not defined in policy.\n",
136 p_in->name);
137 if (pol->reject_unknown)
138 goto err;
139 p_out->num_perms = 0;
140 print_unknown_handle = true;
141 continue;
142 }
143
144 k = 0;
145 while (p_in->perms[k]) {
146 /* An empty permission string skips ahead */
147 if (!*p_in->perms[k]) {
148 k++;
149 continue;
150 }
151 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
152 p_in->perms[k]);
153 if (!p_out->perms[k]) {
154 pr_info("SELinux: Permission %s in class %s not defined in policy.\n",
155 p_in->perms[k], p_in->name);
156 if (pol->reject_unknown)
157 goto err;
158 print_unknown_handle = true;
159 }
160
161 k++;
162 }
163 p_out->num_perms = k;
164 }
165
166 if (print_unknown_handle)
167 pr_info("SELinux: the above unknown classes and permissions will be %s\n",
168 pol->allow_unknown ? "allowed" : "denied");
169
170 out_map->size = i;
171 return 0;
172err:
173 kfree(out_map->mapping);
174 out_map->mapping = NULL;
175 return -EINVAL;
176}
177
178/*
179 * Get real, policy values from mapped values
180 */
181
182static u16 unmap_class(struct selinux_map *map, u16 tclass)
183{
184 if (tclass < map->size)
185 return map->mapping[tclass].value;
186
187 return tclass;
188}
189
190/*
191 * Get kernel value for class from its policy value
192 */
193static u16 map_class(struct selinux_map *map, u16 pol_value)
194{
195 u16 i;
196
197 for (i = 1; i < map->size; i++) {
198 if (map->mapping[i].value == pol_value)
199 return i;
200 }
201
202 return SECCLASS_NULL;
203}
204
205static void map_decision(struct selinux_map *map,
206 u16 tclass, struct av_decision *avd,
207 int allow_unknown)
208{
209 if (tclass < map->size) {
210 struct selinux_mapping *mapping = &map->mapping[tclass];
211 unsigned int i, n = mapping->num_perms;
212 u32 result;
213
214 for (i = 0, result = 0; i < n; i++) {
215 if (avd->allowed & mapping->perms[i])
216 result |= 1<<i;
217 if (allow_unknown && !mapping->perms[i])
218 result |= 1<<i;
219 }
220 avd->allowed = result;
221
222 for (i = 0, result = 0; i < n; i++)
223 if (avd->auditallow & mapping->perms[i])
224 result |= 1<<i;
225 avd->auditallow = result;
226
227 for (i = 0, result = 0; i < n; i++) {
228 if (avd->auditdeny & mapping->perms[i])
229 result |= 1<<i;
230 if (!allow_unknown && !mapping->perms[i])
231 result |= 1<<i;
232 }
233 /*
234 * In case the kernel has a bug and requests a permission
235 * between num_perms and the maximum permission number, we
236 * should audit that denial
237 */
238 for (; i < (sizeof(u32)*8); i++)
239 result |= 1<<i;
240 avd->auditdeny = result;
241 }
242}
243
244int security_mls_enabled(struct selinux_state *state)
245{
246 int mls_enabled;
247 struct selinux_policy *policy;
248
249 if (!selinux_initialized(state))
250 return 0;
251
252 rcu_read_lock();
253 policy = rcu_dereference(state->policy);
254 mls_enabled = policy->policydb.mls_enabled;
255 rcu_read_unlock();
256 return mls_enabled;
257}
258
259/*
260 * Return the boolean value of a constraint expression
261 * when it is applied to the specified source and target
262 * security contexts.
263 *
264 * xcontext is a special beast... It is used by the validatetrans rules
265 * only. For these rules, scontext is the context before the transition,
266 * tcontext is the context after the transition, and xcontext is the context
267 * of the process performing the transition. All other callers of
268 * constraint_expr_eval should pass in NULL for xcontext.
269 */
270static int constraint_expr_eval(struct policydb *policydb,
271 struct context *scontext,
272 struct context *tcontext,
273 struct context *xcontext,
274 struct constraint_expr *cexpr)
275{
276 u32 val1, val2;
277 struct context *c;
278 struct role_datum *r1, *r2;
279 struct mls_level *l1, *l2;
280 struct constraint_expr *e;
281 int s[CEXPR_MAXDEPTH];
282 int sp = -1;
283
284 for (e = cexpr; e; e = e->next) {
285 switch (e->expr_type) {
286 case CEXPR_NOT:
287 BUG_ON(sp < 0);
288 s[sp] = !s[sp];
289 break;
290 case CEXPR_AND:
291 BUG_ON(sp < 1);
292 sp--;
293 s[sp] &= s[sp + 1];
294 break;
295 case CEXPR_OR:
296 BUG_ON(sp < 1);
297 sp--;
298 s[sp] |= s[sp + 1];
299 break;
300 case CEXPR_ATTR:
301 if (sp == (CEXPR_MAXDEPTH - 1))
302 return 0;
303 switch (e->attr) {
304 case CEXPR_USER:
305 val1 = scontext->user;
306 val2 = tcontext->user;
307 break;
308 case CEXPR_TYPE:
309 val1 = scontext->type;
310 val2 = tcontext->type;
311 break;
312 case CEXPR_ROLE:
313 val1 = scontext->role;
314 val2 = tcontext->role;
315 r1 = policydb->role_val_to_struct[val1 - 1];
316 r2 = policydb->role_val_to_struct[val2 - 1];
317 switch (e->op) {
318 case CEXPR_DOM:
319 s[++sp] = ebitmap_get_bit(&r1->dominates,
320 val2 - 1);
321 continue;
322 case CEXPR_DOMBY:
323 s[++sp] = ebitmap_get_bit(&r2->dominates,
324 val1 - 1);
325 continue;
326 case CEXPR_INCOMP:
327 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
328 val2 - 1) &&
329 !ebitmap_get_bit(&r2->dominates,
330 val1 - 1));
331 continue;
332 default:
333 break;
334 }
335 break;
336 case CEXPR_L1L2:
337 l1 = &(scontext->range.level[0]);
338 l2 = &(tcontext->range.level[0]);
339 goto mls_ops;
340 case CEXPR_L1H2:
341 l1 = &(scontext->range.level[0]);
342 l2 = &(tcontext->range.level[1]);
343 goto mls_ops;
344 case CEXPR_H1L2:
345 l1 = &(scontext->range.level[1]);
346 l2 = &(tcontext->range.level[0]);
347 goto mls_ops;
348 case CEXPR_H1H2:
349 l1 = &(scontext->range.level[1]);
350 l2 = &(tcontext->range.level[1]);
351 goto mls_ops;
352 case CEXPR_L1H1:
353 l1 = &(scontext->range.level[0]);
354 l2 = &(scontext->range.level[1]);
355 goto mls_ops;
356 case CEXPR_L2H2:
357 l1 = &(tcontext->range.level[0]);
358 l2 = &(tcontext->range.level[1]);
359 goto mls_ops;
360mls_ops:
361 switch (e->op) {
362 case CEXPR_EQ:
363 s[++sp] = mls_level_eq(l1, l2);
364 continue;
365 case CEXPR_NEQ:
366 s[++sp] = !mls_level_eq(l1, l2);
367 continue;
368 case CEXPR_DOM:
369 s[++sp] = mls_level_dom(l1, l2);
370 continue;
371 case CEXPR_DOMBY:
372 s[++sp] = mls_level_dom(l2, l1);
373 continue;
374 case CEXPR_INCOMP:
375 s[++sp] = mls_level_incomp(l2, l1);
376 continue;
377 default:
378 BUG();
379 return 0;
380 }
381 break;
382 default:
383 BUG();
384 return 0;
385 }
386
387 switch (e->op) {
388 case CEXPR_EQ:
389 s[++sp] = (val1 == val2);
390 break;
391 case CEXPR_NEQ:
392 s[++sp] = (val1 != val2);
393 break;
394 default:
395 BUG();
396 return 0;
397 }
398 break;
399 case CEXPR_NAMES:
400 if (sp == (CEXPR_MAXDEPTH-1))
401 return 0;
402 c = scontext;
403 if (e->attr & CEXPR_TARGET)
404 c = tcontext;
405 else if (e->attr & CEXPR_XTARGET) {
406 c = xcontext;
407 if (!c) {
408 BUG();
409 return 0;
410 }
411 }
412 if (e->attr & CEXPR_USER)
413 val1 = c->user;
414 else if (e->attr & CEXPR_ROLE)
415 val1 = c->role;
416 else if (e->attr & CEXPR_TYPE)
417 val1 = c->type;
418 else {
419 BUG();
420 return 0;
421 }
422
423 switch (e->op) {
424 case CEXPR_EQ:
425 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
426 break;
427 case CEXPR_NEQ:
428 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
429 break;
430 default:
431 BUG();
432 return 0;
433 }
434 break;
435 default:
436 BUG();
437 return 0;
438 }
439 }
440
441 BUG_ON(sp != 0);
442 return s[0];
443}
444
445/*
446 * security_dump_masked_av - dumps masked permissions during
447 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
448 */
449static int dump_masked_av_helper(void *k, void *d, void *args)
450{
451 struct perm_datum *pdatum = d;
452 char **permission_names = args;
453
454 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
455
456 permission_names[pdatum->value - 1] = (char *)k;
457
458 return 0;
459}
460
461static void security_dump_masked_av(struct policydb *policydb,
462 struct context *scontext,
463 struct context *tcontext,
464 u16 tclass,
465 u32 permissions,
466 const char *reason)
467{
468 struct common_datum *common_dat;
469 struct class_datum *tclass_dat;
470 struct audit_buffer *ab;
471 char *tclass_name;
472 char *scontext_name = NULL;
473 char *tcontext_name = NULL;
474 char *permission_names[32];
475 int index;
476 u32 length;
477 bool need_comma = false;
478
479 if (!permissions)
480 return;
481
482 tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1);
483 tclass_dat = policydb->class_val_to_struct[tclass - 1];
484 common_dat = tclass_dat->comdatum;
485
486 /* init permission_names */
487 if (common_dat &&
488 hashtab_map(&common_dat->permissions.table,
489 dump_masked_av_helper, permission_names) < 0)
490 goto out;
491
492 if (hashtab_map(&tclass_dat->permissions.table,
493 dump_masked_av_helper, permission_names) < 0)
494 goto out;
495
496 /* get scontext/tcontext in text form */
497 if (context_struct_to_string(policydb, scontext,
498 &scontext_name, &length) < 0)
499 goto out;
500
501 if (context_struct_to_string(policydb, tcontext,
502 &tcontext_name, &length) < 0)
503 goto out;
504
505 /* audit a message */
506 ab = audit_log_start(audit_context(),
507 GFP_ATOMIC, AUDIT_SELINUX_ERR);
508 if (!ab)
509 goto out;
510
511 audit_log_format(ab, "op=security_compute_av reason=%s "
512 "scontext=%s tcontext=%s tclass=%s perms=",
513 reason, scontext_name, tcontext_name, tclass_name);
514
515 for (index = 0; index < 32; index++) {
516 u32 mask = (1 << index);
517
518 if ((mask & permissions) == 0)
519 continue;
520
521 audit_log_format(ab, "%s%s",
522 need_comma ? "," : "",
523 permission_names[index]
524 ? permission_names[index] : "????");
525 need_comma = true;
526 }
527 audit_log_end(ab);
528out:
529 /* release scontext/tcontext */
530 kfree(tcontext_name);
531 kfree(scontext_name);
532
533 return;
534}
535
536/*
537 * security_boundary_permission - drops violated permissions
538 * on boundary constraint.
539 */
540static void type_attribute_bounds_av(struct policydb *policydb,
541 struct context *scontext,
542 struct context *tcontext,
543 u16 tclass,
544 struct av_decision *avd)
545{
546 struct context lo_scontext;
547 struct context lo_tcontext, *tcontextp = tcontext;
548 struct av_decision lo_avd;
549 struct type_datum *source;
550 struct type_datum *target;
551 u32 masked = 0;
552
553 source = policydb->type_val_to_struct[scontext->type - 1];
554 BUG_ON(!source);
555
556 if (!source->bounds)
557 return;
558
559 target = policydb->type_val_to_struct[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 xperms->len = 1;
613}
614
615/*
616 * Compute access vectors and extended permissions based on a context
617 * structure pair for the permissions in a particular class.
618 */
619static void context_struct_compute_av(struct policydb *policydb,
620 struct context *scontext,
621 struct context *tcontext,
622 u16 tclass,
623 struct av_decision *avd,
624 struct extended_perms *xperms)
625{
626 struct constraint_node *constraint;
627 struct role_allow *ra;
628 struct avtab_key avkey;
629 struct avtab_node *node;
630 struct class_datum *tclass_datum;
631 struct ebitmap *sattr, *tattr;
632 struct ebitmap_node *snode, *tnode;
633 unsigned int i, j;
634
635 avd->allowed = 0;
636 avd->auditallow = 0;
637 avd->auditdeny = 0xffffffff;
638 if (xperms) {
639 memset(&xperms->drivers, 0, sizeof(xperms->drivers));
640 xperms->len = 0;
641 }
642
643 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
644 if (printk_ratelimit())
645 pr_warn("SELinux: Invalid class %hu\n", tclass);
646 return;
647 }
648
649 tclass_datum = policydb->class_val_to_struct[tclass - 1];
650
651 /*
652 * If a specific type enforcement rule was defined for
653 * this permission check, then use it.
654 */
655 avkey.target_class = tclass;
656 avkey.specified = AVTAB_AV | AVTAB_XPERMS;
657 sattr = &policydb->type_attr_map_array[scontext->type - 1];
658 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
659 ebitmap_for_each_positive_bit(sattr, snode, i) {
660 ebitmap_for_each_positive_bit(tattr, tnode, j) {
661 avkey.source_type = i + 1;
662 avkey.target_type = j + 1;
663 for (node = avtab_search_node(&policydb->te_avtab,
664 &avkey);
665 node;
666 node = avtab_search_node_next(node, avkey.specified)) {
667 if (node->key.specified == AVTAB_ALLOWED)
668 avd->allowed |= node->datum.u.data;
669 else if (node->key.specified == AVTAB_AUDITALLOW)
670 avd->auditallow |= node->datum.u.data;
671 else if (node->key.specified == AVTAB_AUDITDENY)
672 avd->auditdeny &= node->datum.u.data;
673 else if (xperms && (node->key.specified & AVTAB_XPERMS))
674 services_compute_xperms_drivers(xperms, node);
675 }
676
677 /* Check conditional av table for additional permissions */
678 cond_compute_av(&policydb->te_cond_avtab, &avkey,
679 avd, xperms);
680
681 }
682 }
683
684 /*
685 * Remove any permissions prohibited by a constraint (this includes
686 * the MLS policy).
687 */
688 constraint = tclass_datum->constraints;
689 while (constraint) {
690 if ((constraint->permissions & (avd->allowed)) &&
691 !constraint_expr_eval(policydb, scontext, tcontext, NULL,
692 constraint->expr)) {
693 avd->allowed &= ~(constraint->permissions);
694 }
695 constraint = constraint->next;
696 }
697
698 /*
699 * If checking process transition permission and the
700 * role is changing, then check the (current_role, new_role)
701 * pair.
702 */
703 if (tclass == policydb->process_class &&
704 (avd->allowed & policydb->process_trans_perms) &&
705 scontext->role != tcontext->role) {
706 for (ra = policydb->role_allow; ra; ra = ra->next) {
707 if (scontext->role == ra->role &&
708 tcontext->role == ra->new_role)
709 break;
710 }
711 if (!ra)
712 avd->allowed &= ~policydb->process_trans_perms;
713 }
714
715 /*
716 * If the given source and target types have boundary
717 * constraint, lazy checks have to mask any violated
718 * permission and notice it to userspace via audit.
719 */
720 type_attribute_bounds_av(policydb, scontext, tcontext,
721 tclass, avd);
722}
723
724static int security_validtrans_handle_fail(struct selinux_state *state,
725 struct selinux_policy *policy,
726 struct sidtab_entry *oentry,
727 struct sidtab_entry *nentry,
728 struct sidtab_entry *tentry,
729 u16 tclass)
730{
731 struct policydb *p = &policy->policydb;
732 struct sidtab *sidtab = policy->sidtab;
733 char *o = NULL, *n = NULL, *t = NULL;
734 u32 olen, nlen, tlen;
735
736 if (sidtab_entry_to_string(p, sidtab, oentry, &o, &olen))
737 goto out;
738 if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen))
739 goto out;
740 if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen))
741 goto out;
742 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
743 "op=security_validate_transition seresult=denied"
744 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
745 o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
746out:
747 kfree(o);
748 kfree(n);
749 kfree(t);
750
751 if (!enforcing_enabled(state))
752 return 0;
753 return -EPERM;
754}
755
756static int security_compute_validatetrans(struct selinux_state *state,
757 u32 oldsid, u32 newsid, u32 tasksid,
758 u16 orig_tclass, bool user)
759{
760 struct selinux_policy *policy;
761 struct policydb *policydb;
762 struct sidtab *sidtab;
763 struct sidtab_entry *oentry;
764 struct sidtab_entry *nentry;
765 struct sidtab_entry *tentry;
766 struct class_datum *tclass_datum;
767 struct constraint_node *constraint;
768 u16 tclass;
769 int rc = 0;
770
771
772 if (!selinux_initialized(state))
773 return 0;
774
775 rcu_read_lock();
776
777 policy = rcu_dereference(state->policy);
778 policydb = &policy->policydb;
779 sidtab = policy->sidtab;
780
781 if (!user)
782 tclass = unmap_class(&policy->map, orig_tclass);
783 else
784 tclass = orig_tclass;
785
786 if (!tclass || tclass > policydb->p_classes.nprim) {
787 rc = -EINVAL;
788 goto out;
789 }
790 tclass_datum = policydb->class_val_to_struct[tclass - 1];
791
792 oentry = sidtab_search_entry(sidtab, oldsid);
793 if (!oentry) {
794 pr_err("SELinux: %s: unrecognized SID %d\n",
795 __func__, oldsid);
796 rc = -EINVAL;
797 goto out;
798 }
799
800 nentry = sidtab_search_entry(sidtab, newsid);
801 if (!nentry) {
802 pr_err("SELinux: %s: unrecognized SID %d\n",
803 __func__, newsid);
804 rc = -EINVAL;
805 goto out;
806 }
807
808 tentry = sidtab_search_entry(sidtab, tasksid);
809 if (!tentry) {
810 pr_err("SELinux: %s: unrecognized SID %d\n",
811 __func__, tasksid);
812 rc = -EINVAL;
813 goto out;
814 }
815
816 constraint = tclass_datum->validatetrans;
817 while (constraint) {
818 if (!constraint_expr_eval(policydb, &oentry->context,
819 &nentry->context, &tentry->context,
820 constraint->expr)) {
821 if (user)
822 rc = -EPERM;
823 else
824 rc = security_validtrans_handle_fail(state,
825 policy,
826 oentry,
827 nentry,
828 tentry,
829 tclass);
830 goto out;
831 }
832 constraint = constraint->next;
833 }
834
835out:
836 rcu_read_unlock();
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 * @state: SELinux state
863 * @oldsid : current security identifier
864 * @newsid : destinated security identifier
865 */
866int security_bounded_transition(struct selinux_state *state,
867 u32 old_sid, u32 new_sid)
868{
869 struct selinux_policy *policy;
870 struct policydb *policydb;
871 struct sidtab *sidtab;
872 struct sidtab_entry *old_entry, *new_entry;
873 struct type_datum *type;
874 int index;
875 int rc;
876
877 if (!selinux_initialized(state))
878 return 0;
879
880 rcu_read_lock();
881 policy = rcu_dereference(state->policy);
882 policydb = &policy->policydb;
883 sidtab = policy->sidtab;
884
885 rc = -EINVAL;
886 old_entry = sidtab_search_entry(sidtab, old_sid);
887 if (!old_entry) {
888 pr_err("SELinux: %s: unrecognized SID %u\n",
889 __func__, old_sid);
890 goto out;
891 }
892
893 rc = -EINVAL;
894 new_entry = sidtab_search_entry(sidtab, new_sid);
895 if (!new_entry) {
896 pr_err("SELinux: %s: unrecognized SID %u\n",
897 __func__, new_sid);
898 goto out;
899 }
900
901 rc = 0;
902 /* type/domain unchanged */
903 if (old_entry->context.type == new_entry->context.type)
904 goto out;
905
906 index = new_entry->context.type;
907 while (true) {
908 type = policydb->type_val_to_struct[index - 1];
909 BUG_ON(!type);
910
911 /* not bounded anymore */
912 rc = -EPERM;
913 if (!type->bounds)
914 break;
915
916 /* @newsid is bounded by @oldsid */
917 rc = 0;
918 if (type->bounds == old_entry->context.type)
919 break;
920
921 index = type->bounds;
922 }
923
924 if (rc) {
925 char *old_name = NULL;
926 char *new_name = NULL;
927 u32 length;
928
929 if (!sidtab_entry_to_string(policydb, sidtab, old_entry,
930 &old_name, &length) &&
931 !sidtab_entry_to_string(policydb, sidtab, new_entry,
932 &new_name, &length)) {
933 audit_log(audit_context(),
934 GFP_ATOMIC, AUDIT_SELINUX_ERR,
935 "op=security_bounded_transition "
936 "seresult=denied "
937 "oldcontext=%s newcontext=%s",
938 old_name, new_name);
939 }
940 kfree(new_name);
941 kfree(old_name);
942 }
943out:
944 rcu_read_unlock();
945
946 return rc;
947}
948
949static void avd_init(struct selinux_policy *policy, struct av_decision *avd)
950{
951 avd->allowed = 0;
952 avd->auditallow = 0;
953 avd->auditdeny = 0xffffffff;
954 if (policy)
955 avd->seqno = policy->latest_granting;
956 else
957 avd->seqno = 0;
958 avd->flags = 0;
959}
960
961void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
962 struct avtab_node *node)
963{
964 unsigned int i;
965
966 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
967 if (xpermd->driver != node->datum.u.xperms->driver)
968 return;
969 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
970 if (!security_xperm_test(node->datum.u.xperms->perms.p,
971 xpermd->driver))
972 return;
973 } else {
974 BUG();
975 }
976
977 if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
978 xpermd->used |= XPERMS_ALLOWED;
979 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
980 memset(xpermd->allowed->p, 0xff,
981 sizeof(xpermd->allowed->p));
982 }
983 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
984 for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++)
985 xpermd->allowed->p[i] |=
986 node->datum.u.xperms->perms.p[i];
987 }
988 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
989 xpermd->used |= XPERMS_AUDITALLOW;
990 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
991 memset(xpermd->auditallow->p, 0xff,
992 sizeof(xpermd->auditallow->p));
993 }
994 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
995 for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++)
996 xpermd->auditallow->p[i] |=
997 node->datum.u.xperms->perms.p[i];
998 }
999 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
1000 xpermd->used |= XPERMS_DONTAUDIT;
1001 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
1002 memset(xpermd->dontaudit->p, 0xff,
1003 sizeof(xpermd->dontaudit->p));
1004 }
1005 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
1006 for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++)
1007 xpermd->dontaudit->p[i] |=
1008 node->datum.u.xperms->perms.p[i];
1009 }
1010 } else {
1011 BUG();
1012 }
1013}
1014
1015void security_compute_xperms_decision(struct selinux_state *state,
1016 u32 ssid,
1017 u32 tsid,
1018 u16 orig_tclass,
1019 u8 driver,
1020 struct extended_perms_decision *xpermd)
1021{
1022 struct selinux_policy *policy;
1023 struct policydb *policydb;
1024 struct sidtab *sidtab;
1025 u16 tclass;
1026 struct context *scontext, *tcontext;
1027 struct avtab_key avkey;
1028 struct avtab_node *node;
1029 struct ebitmap *sattr, *tattr;
1030 struct ebitmap_node *snode, *tnode;
1031 unsigned int i, j;
1032
1033 xpermd->driver = driver;
1034 xpermd->used = 0;
1035 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1036 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1037 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1038
1039 rcu_read_lock();
1040 if (!selinux_initialized(state))
1041 goto allow;
1042
1043 policy = rcu_dereference(state->policy);
1044 policydb = &policy->policydb;
1045 sidtab = policy->sidtab;
1046
1047 scontext = sidtab_search(sidtab, ssid);
1048 if (!scontext) {
1049 pr_err("SELinux: %s: unrecognized SID %d\n",
1050 __func__, ssid);
1051 goto out;
1052 }
1053
1054 tcontext = sidtab_search(sidtab, tsid);
1055 if (!tcontext) {
1056 pr_err("SELinux: %s: unrecognized SID %d\n",
1057 __func__, tsid);
1058 goto out;
1059 }
1060
1061 tclass = unmap_class(&policy->map, orig_tclass);
1062 if (unlikely(orig_tclass && !tclass)) {
1063 if (policydb->allow_unknown)
1064 goto allow;
1065 goto out;
1066 }
1067
1068
1069 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1070 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1071 goto out;
1072 }
1073
1074 avkey.target_class = tclass;
1075 avkey.specified = AVTAB_XPERMS;
1076 sattr = &policydb->type_attr_map_array[scontext->type - 1];
1077 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
1078 ebitmap_for_each_positive_bit(sattr, snode, i) {
1079 ebitmap_for_each_positive_bit(tattr, tnode, j) {
1080 avkey.source_type = i + 1;
1081 avkey.target_type = j + 1;
1082 for (node = avtab_search_node(&policydb->te_avtab,
1083 &avkey);
1084 node;
1085 node = avtab_search_node_next(node, avkey.specified))
1086 services_compute_xperms_decision(xpermd, node);
1087
1088 cond_compute_xperms(&policydb->te_cond_avtab,
1089 &avkey, xpermd);
1090 }
1091 }
1092out:
1093 rcu_read_unlock();
1094 return;
1095allow:
1096 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1097 goto out;
1098}
1099
1100/**
1101 * security_compute_av - Compute access vector decisions.
1102 * @state: SELinux state
1103 * @ssid: source security identifier
1104 * @tsid: target security identifier
1105 * @tclass: target security class
1106 * @avd: access vector decisions
1107 * @xperms: extended permissions
1108 *
1109 * Compute a set of access vector decisions based on the
1110 * SID pair (@ssid, @tsid) for the permissions in @tclass.
1111 */
1112void security_compute_av(struct selinux_state *state,
1113 u32 ssid,
1114 u32 tsid,
1115 u16 orig_tclass,
1116 struct av_decision *avd,
1117 struct extended_perms *xperms)
1118{
1119 struct selinux_policy *policy;
1120 struct policydb *policydb;
1121 struct sidtab *sidtab;
1122 u16 tclass;
1123 struct context *scontext = NULL, *tcontext = NULL;
1124
1125 rcu_read_lock();
1126 policy = rcu_dereference(state->policy);
1127 avd_init(policy, avd);
1128 xperms->len = 0;
1129 if (!selinux_initialized(state))
1130 goto allow;
1131
1132 policydb = &policy->policydb;
1133 sidtab = policy->sidtab;
1134
1135 scontext = sidtab_search(sidtab, ssid);
1136 if (!scontext) {
1137 pr_err("SELinux: %s: unrecognized SID %d\n",
1138 __func__, ssid);
1139 goto out;
1140 }
1141
1142 /* permissive domain? */
1143 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1144 avd->flags |= AVD_FLAGS_PERMISSIVE;
1145
1146 tcontext = sidtab_search(sidtab, tsid);
1147 if (!tcontext) {
1148 pr_err("SELinux: %s: unrecognized SID %d\n",
1149 __func__, tsid);
1150 goto out;
1151 }
1152
1153 tclass = unmap_class(&policy->map, orig_tclass);
1154 if (unlikely(orig_tclass && !tclass)) {
1155 if (policydb->allow_unknown)
1156 goto allow;
1157 goto out;
1158 }
1159 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1160 xperms);
1161 map_decision(&policy->map, orig_tclass, avd,
1162 policydb->allow_unknown);
1163out:
1164 rcu_read_unlock();
1165 return;
1166allow:
1167 avd->allowed = 0xffffffff;
1168 goto out;
1169}
1170
1171void security_compute_av_user(struct selinux_state *state,
1172 u32 ssid,
1173 u32 tsid,
1174 u16 tclass,
1175 struct av_decision *avd)
1176{
1177 struct selinux_policy *policy;
1178 struct policydb *policydb;
1179 struct sidtab *sidtab;
1180 struct context *scontext = NULL, *tcontext = NULL;
1181
1182 rcu_read_lock();
1183 policy = rcu_dereference(state->policy);
1184 avd_init(policy, avd);
1185 if (!selinux_initialized(state))
1186 goto allow;
1187
1188 policydb = &policy->policydb;
1189 sidtab = policy->sidtab;
1190
1191 scontext = sidtab_search(sidtab, ssid);
1192 if (!scontext) {
1193 pr_err("SELinux: %s: unrecognized SID %d\n",
1194 __func__, ssid);
1195 goto out;
1196 }
1197
1198 /* permissive domain? */
1199 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1200 avd->flags |= AVD_FLAGS_PERMISSIVE;
1201
1202 tcontext = sidtab_search(sidtab, tsid);
1203 if (!tcontext) {
1204 pr_err("SELinux: %s: unrecognized SID %d\n",
1205 __func__, tsid);
1206 goto out;
1207 }
1208
1209 if (unlikely(!tclass)) {
1210 if (policydb->allow_unknown)
1211 goto allow;
1212 goto out;
1213 }
1214
1215 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1216 NULL);
1217 out:
1218 rcu_read_unlock();
1219 return;
1220allow:
1221 avd->allowed = 0xffffffff;
1222 goto out;
1223}
1224
1225/*
1226 * Write the security context string representation of
1227 * the context structure `context' into a dynamically
1228 * allocated string of the correct size. Set `*scontext'
1229 * to point to this string and set `*scontext_len' to
1230 * the length of the string.
1231 */
1232static int context_struct_to_string(struct policydb *p,
1233 struct context *context,
1234 char **scontext, u32 *scontext_len)
1235{
1236 char *scontextp;
1237
1238 if (scontext)
1239 *scontext = NULL;
1240 *scontext_len = 0;
1241
1242 if (context->len) {
1243 *scontext_len = context->len;
1244 if (scontext) {
1245 *scontext = kstrdup(context->str, GFP_ATOMIC);
1246 if (!(*scontext))
1247 return -ENOMEM;
1248 }
1249 return 0;
1250 }
1251
1252 /* Compute the size of the context. */
1253 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1254 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1255 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1256 *scontext_len += mls_compute_context_len(p, context);
1257
1258 if (!scontext)
1259 return 0;
1260
1261 /* Allocate space for the context; caller must free this space. */
1262 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1263 if (!scontextp)
1264 return -ENOMEM;
1265 *scontext = scontextp;
1266
1267 /*
1268 * Copy the user name, role name and type name into the context.
1269 */
1270 scontextp += sprintf(scontextp, "%s:%s:%s",
1271 sym_name(p, SYM_USERS, context->user - 1),
1272 sym_name(p, SYM_ROLES, context->role - 1),
1273 sym_name(p, SYM_TYPES, context->type - 1));
1274
1275 mls_sid_to_context(p, context, &scontextp);
1276
1277 *scontextp = 0;
1278
1279 return 0;
1280}
1281
1282static int sidtab_entry_to_string(struct policydb *p,
1283 struct sidtab *sidtab,
1284 struct sidtab_entry *entry,
1285 char **scontext, u32 *scontext_len)
1286{
1287 int rc = sidtab_sid2str_get(sidtab, entry, scontext, scontext_len);
1288
1289 if (rc != -ENOENT)
1290 return rc;
1291
1292 rc = context_struct_to_string(p, &entry->context, scontext,
1293 scontext_len);
1294 if (!rc && scontext)
1295 sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len);
1296 return rc;
1297}
1298
1299#include "initial_sid_to_string.h"
1300
1301int security_sidtab_hash_stats(struct selinux_state *state, char *page)
1302{
1303 struct selinux_policy *policy;
1304 int rc;
1305
1306 if (!selinux_initialized(state)) {
1307 pr_err("SELinux: %s: called before initial load_policy\n",
1308 __func__);
1309 return -EINVAL;
1310 }
1311
1312 rcu_read_lock();
1313 policy = rcu_dereference(state->policy);
1314 rc = sidtab_hash_stats(policy->sidtab, page);
1315 rcu_read_unlock();
1316
1317 return rc;
1318}
1319
1320const char *security_get_initial_sid_context(u32 sid)
1321{
1322 if (unlikely(sid > SECINITSID_NUM))
1323 return NULL;
1324 return initial_sid_to_string[sid];
1325}
1326
1327static int security_sid_to_context_core(struct selinux_state *state,
1328 u32 sid, char **scontext,
1329 u32 *scontext_len, int force,
1330 int only_invalid)
1331{
1332 struct selinux_policy *policy;
1333 struct policydb *policydb;
1334 struct sidtab *sidtab;
1335 struct sidtab_entry *entry;
1336 int rc = 0;
1337
1338 if (scontext)
1339 *scontext = NULL;
1340 *scontext_len = 0;
1341
1342 if (!selinux_initialized(state)) {
1343 if (sid <= SECINITSID_NUM) {
1344 char *scontextp;
1345 const char *s = initial_sid_to_string[sid];
1346
1347 if (!s)
1348 return -EINVAL;
1349 *scontext_len = strlen(s) + 1;
1350 if (!scontext)
1351 return 0;
1352 scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC);
1353 if (!scontextp)
1354 return -ENOMEM;
1355 *scontext = scontextp;
1356 return 0;
1357 }
1358 pr_err("SELinux: %s: called before initial "
1359 "load_policy on unknown SID %d\n", __func__, sid);
1360 return -EINVAL;
1361 }
1362 rcu_read_lock();
1363 policy = rcu_dereference(state->policy);
1364 policydb = &policy->policydb;
1365 sidtab = policy->sidtab;
1366
1367 if (force)
1368 entry = sidtab_search_entry_force(sidtab, sid);
1369 else
1370 entry = sidtab_search_entry(sidtab, sid);
1371 if (!entry) {
1372 pr_err("SELinux: %s: unrecognized SID %d\n",
1373 __func__, sid);
1374 rc = -EINVAL;
1375 goto out_unlock;
1376 }
1377 if (only_invalid && !entry->context.len)
1378 goto out_unlock;
1379
1380 rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext,
1381 scontext_len);
1382
1383out_unlock:
1384 rcu_read_unlock();
1385 return rc;
1386
1387}
1388
1389/**
1390 * security_sid_to_context - Obtain a context for a given SID.
1391 * @state: SELinux state
1392 * @sid: security identifier, SID
1393 * @scontext: security context
1394 * @scontext_len: length in bytes
1395 *
1396 * Write the string representation of the context associated with @sid
1397 * into a dynamically allocated string of the correct size. Set @scontext
1398 * to point to this string and set @scontext_len to the length of the string.
1399 */
1400int security_sid_to_context(struct selinux_state *state,
1401 u32 sid, char **scontext, u32 *scontext_len)
1402{
1403 return security_sid_to_context_core(state, sid, scontext,
1404 scontext_len, 0, 0);
1405}
1406
1407int security_sid_to_context_force(struct selinux_state *state, u32 sid,
1408 char **scontext, u32 *scontext_len)
1409{
1410 return security_sid_to_context_core(state, sid, scontext,
1411 scontext_len, 1, 0);
1412}
1413
1414/**
1415 * security_sid_to_context_inval - Obtain a context for a given SID if it
1416 * is invalid.
1417 * @state: SELinux state
1418 * @sid: security identifier, SID
1419 * @scontext: security context
1420 * @scontext_len: length in bytes
1421 *
1422 * Write the string representation of the context associated with @sid
1423 * into a dynamically allocated string of the correct size, but only if the
1424 * context is invalid in the current policy. Set @scontext to point to
1425 * this string (or NULL if the context is valid) and set @scontext_len to
1426 * the length of the string (or 0 if the context is valid).
1427 */
1428int security_sid_to_context_inval(struct selinux_state *state, u32 sid,
1429 char **scontext, u32 *scontext_len)
1430{
1431 return security_sid_to_context_core(state, sid, scontext,
1432 scontext_len, 1, 1);
1433}
1434
1435/*
1436 * Caveat: Mutates scontext.
1437 */
1438static int string_to_context_struct(struct policydb *pol,
1439 struct sidtab *sidtabp,
1440 char *scontext,
1441 struct context *ctx,
1442 u32 def_sid)
1443{
1444 struct role_datum *role;
1445 struct type_datum *typdatum;
1446 struct user_datum *usrdatum;
1447 char *scontextp, *p, oldc;
1448 int rc = 0;
1449
1450 context_init(ctx);
1451
1452 /* Parse the security context. */
1453
1454 rc = -EINVAL;
1455 scontextp = (char *) scontext;
1456
1457 /* Extract the user. */
1458 p = scontextp;
1459 while (*p && *p != ':')
1460 p++;
1461
1462 if (*p == 0)
1463 goto out;
1464
1465 *p++ = 0;
1466
1467 usrdatum = symtab_search(&pol->p_users, scontextp);
1468 if (!usrdatum)
1469 goto out;
1470
1471 ctx->user = usrdatum->value;
1472
1473 /* Extract role. */
1474 scontextp = p;
1475 while (*p && *p != ':')
1476 p++;
1477
1478 if (*p == 0)
1479 goto out;
1480
1481 *p++ = 0;
1482
1483 role = symtab_search(&pol->p_roles, scontextp);
1484 if (!role)
1485 goto out;
1486 ctx->role = role->value;
1487
1488 /* Extract type. */
1489 scontextp = p;
1490 while (*p && *p != ':')
1491 p++;
1492 oldc = *p;
1493 *p++ = 0;
1494
1495 typdatum = symtab_search(&pol->p_types, scontextp);
1496 if (!typdatum || typdatum->attribute)
1497 goto out;
1498
1499 ctx->type = typdatum->value;
1500
1501 rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid);
1502 if (rc)
1503 goto out;
1504
1505 /* Check the validity of the new context. */
1506 rc = -EINVAL;
1507 if (!policydb_context_isvalid(pol, ctx))
1508 goto out;
1509 rc = 0;
1510out:
1511 if (rc)
1512 context_destroy(ctx);
1513 return rc;
1514}
1515
1516static int security_context_to_sid_core(struct selinux_state *state,
1517 const char *scontext, u32 scontext_len,
1518 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1519 int force)
1520{
1521 struct selinux_policy *policy;
1522 struct policydb *policydb;
1523 struct sidtab *sidtab;
1524 char *scontext2, *str = NULL;
1525 struct context context;
1526 int rc = 0;
1527
1528 /* An empty security context is never valid. */
1529 if (!scontext_len)
1530 return -EINVAL;
1531
1532 /* Copy the string to allow changes and ensure a NUL terminator */
1533 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags);
1534 if (!scontext2)
1535 return -ENOMEM;
1536
1537 if (!selinux_initialized(state)) {
1538 int i;
1539
1540 for (i = 1; i < SECINITSID_NUM; i++) {
1541 const char *s = initial_sid_to_string[i];
1542
1543 if (s && !strcmp(s, scontext2)) {
1544 *sid = i;
1545 goto out;
1546 }
1547 }
1548 *sid = SECINITSID_KERNEL;
1549 goto out;
1550 }
1551 *sid = SECSID_NULL;
1552
1553 if (force) {
1554 /* Save another copy for storing in uninterpreted form */
1555 rc = -ENOMEM;
1556 str = kstrdup(scontext2, gfp_flags);
1557 if (!str)
1558 goto out;
1559 }
1560retry:
1561 rcu_read_lock();
1562 policy = rcu_dereference(state->policy);
1563 policydb = &policy->policydb;
1564 sidtab = policy->sidtab;
1565 rc = string_to_context_struct(policydb, sidtab, scontext2,
1566 &context, def_sid);
1567 if (rc == -EINVAL && force) {
1568 context.str = str;
1569 context.len = strlen(str) + 1;
1570 str = NULL;
1571 } else if (rc)
1572 goto out_unlock;
1573 rc = sidtab_context_to_sid(sidtab, &context, sid);
1574 if (rc == -ESTALE) {
1575 rcu_read_unlock();
1576 if (context.str) {
1577 str = context.str;
1578 context.str = NULL;
1579 }
1580 context_destroy(&context);
1581 goto retry;
1582 }
1583 context_destroy(&context);
1584out_unlock:
1585 rcu_read_unlock();
1586out:
1587 kfree(scontext2);
1588 kfree(str);
1589 return rc;
1590}
1591
1592/**
1593 * security_context_to_sid - Obtain a SID for a given security context.
1594 * @state: SELinux state
1595 * @scontext: security context
1596 * @scontext_len: length in bytes
1597 * @sid: security identifier, SID
1598 * @gfp: context for the allocation
1599 *
1600 * Obtains a SID associated with the security context that
1601 * has the string representation specified by @scontext.
1602 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1603 * memory is available, or 0 on success.
1604 */
1605int security_context_to_sid(struct selinux_state *state,
1606 const char *scontext, u32 scontext_len, u32 *sid,
1607 gfp_t gfp)
1608{
1609 return security_context_to_sid_core(state, scontext, scontext_len,
1610 sid, SECSID_NULL, gfp, 0);
1611}
1612
1613int security_context_str_to_sid(struct selinux_state *state,
1614 const char *scontext, u32 *sid, gfp_t gfp)
1615{
1616 return security_context_to_sid(state, scontext, strlen(scontext),
1617 sid, gfp);
1618}
1619
1620/**
1621 * security_context_to_sid_default - Obtain a SID for a given security context,
1622 * falling back to specified default if needed.
1623 *
1624 * @state: SELinux state
1625 * @scontext: security context
1626 * @scontext_len: length in bytes
1627 * @sid: security identifier, SID
1628 * @def_sid: default SID to assign on error
1629 *
1630 * Obtains a SID associated with the security context that
1631 * has the string representation specified by @scontext.
1632 * The default SID is passed to the MLS layer to be used to allow
1633 * kernel labeling of the MLS field if the MLS field is not present
1634 * (for upgrading to MLS without full relabel).
1635 * Implicitly forces adding of the context even if it cannot be mapped yet.
1636 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1637 * memory is available, or 0 on success.
1638 */
1639int security_context_to_sid_default(struct selinux_state *state,
1640 const char *scontext, u32 scontext_len,
1641 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1642{
1643 return security_context_to_sid_core(state, scontext, scontext_len,
1644 sid, def_sid, gfp_flags, 1);
1645}
1646
1647int security_context_to_sid_force(struct selinux_state *state,
1648 const char *scontext, u32 scontext_len,
1649 u32 *sid)
1650{
1651 return security_context_to_sid_core(state, scontext, scontext_len,
1652 sid, SECSID_NULL, GFP_KERNEL, 1);
1653}
1654
1655static int compute_sid_handle_invalid_context(
1656 struct selinux_state *state,
1657 struct selinux_policy *policy,
1658 struct sidtab_entry *sentry,
1659 struct sidtab_entry *tentry,
1660 u16 tclass,
1661 struct context *newcontext)
1662{
1663 struct policydb *policydb = &policy->policydb;
1664 struct sidtab *sidtab = policy->sidtab;
1665 char *s = NULL, *t = NULL, *n = NULL;
1666 u32 slen, tlen, nlen;
1667 struct audit_buffer *ab;
1668
1669 if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen))
1670 goto out;
1671 if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen))
1672 goto out;
1673 if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1674 goto out;
1675 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR);
1676 audit_log_format(ab,
1677 "op=security_compute_sid invalid_context=");
1678 /* no need to record the NUL with untrusted strings */
1679 audit_log_n_untrustedstring(ab, n, nlen - 1);
1680 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s",
1681 s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1682 audit_log_end(ab);
1683out:
1684 kfree(s);
1685 kfree(t);
1686 kfree(n);
1687 if (!enforcing_enabled(state))
1688 return 0;
1689 return -EACCES;
1690}
1691
1692static void filename_compute_type(struct policydb *policydb,
1693 struct context *newcontext,
1694 u32 stype, u32 ttype, u16 tclass,
1695 const char *objname)
1696{
1697 struct filename_trans_key ft;
1698 struct filename_trans_datum *datum;
1699
1700 /*
1701 * Most filename trans rules are going to live in specific directories
1702 * like /dev or /var/run. This bitmap will quickly skip rule searches
1703 * if the ttype does not contain any rules.
1704 */
1705 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1706 return;
1707
1708 ft.ttype = ttype;
1709 ft.tclass = tclass;
1710 ft.name = objname;
1711
1712 datum = policydb_filenametr_search(policydb, &ft);
1713 while (datum) {
1714 if (ebitmap_get_bit(&datum->stypes, stype - 1)) {
1715 newcontext->type = datum->otype;
1716 return;
1717 }
1718 datum = datum->next;
1719 }
1720}
1721
1722static int security_compute_sid(struct selinux_state *state,
1723 u32 ssid,
1724 u32 tsid,
1725 u16 orig_tclass,
1726 u32 specified,
1727 const char *objname,
1728 u32 *out_sid,
1729 bool kern)
1730{
1731 struct selinux_policy *policy;
1732 struct policydb *policydb;
1733 struct sidtab *sidtab;
1734 struct class_datum *cladatum;
1735 struct context *scontext, *tcontext, newcontext;
1736 struct sidtab_entry *sentry, *tentry;
1737 struct avtab_key avkey;
1738 struct avtab_datum *avdatum;
1739 struct avtab_node *node;
1740 u16 tclass;
1741 int rc = 0;
1742 bool sock;
1743
1744 if (!selinux_initialized(state)) {
1745 switch (orig_tclass) {
1746 case SECCLASS_PROCESS: /* kernel value */
1747 *out_sid = ssid;
1748 break;
1749 default:
1750 *out_sid = tsid;
1751 break;
1752 }
1753 goto out;
1754 }
1755
1756retry:
1757 cladatum = NULL;
1758 context_init(&newcontext);
1759
1760 rcu_read_lock();
1761
1762 policy = rcu_dereference(state->policy);
1763
1764 if (kern) {
1765 tclass = unmap_class(&policy->map, orig_tclass);
1766 sock = security_is_socket_class(orig_tclass);
1767 } else {
1768 tclass = orig_tclass;
1769 sock = security_is_socket_class(map_class(&policy->map,
1770 tclass));
1771 }
1772
1773 policydb = &policy->policydb;
1774 sidtab = policy->sidtab;
1775
1776 sentry = sidtab_search_entry(sidtab, ssid);
1777 if (!sentry) {
1778 pr_err("SELinux: %s: unrecognized SID %d\n",
1779 __func__, ssid);
1780 rc = -EINVAL;
1781 goto out_unlock;
1782 }
1783 tentry = sidtab_search_entry(sidtab, tsid);
1784 if (!tentry) {
1785 pr_err("SELinux: %s: unrecognized SID %d\n",
1786 __func__, tsid);
1787 rc = -EINVAL;
1788 goto out_unlock;
1789 }
1790
1791 scontext = &sentry->context;
1792 tcontext = &tentry->context;
1793
1794 if (tclass && tclass <= policydb->p_classes.nprim)
1795 cladatum = policydb->class_val_to_struct[tclass - 1];
1796
1797 /* Set the user identity. */
1798 switch (specified) {
1799 case AVTAB_TRANSITION:
1800 case AVTAB_CHANGE:
1801 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1802 newcontext.user = tcontext->user;
1803 } else {
1804 /* notice this gets both DEFAULT_SOURCE and unset */
1805 /* Use the process user identity. */
1806 newcontext.user = scontext->user;
1807 }
1808 break;
1809 case AVTAB_MEMBER:
1810 /* Use the related object owner. */
1811 newcontext.user = tcontext->user;
1812 break;
1813 }
1814
1815 /* Set the role to default values. */
1816 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1817 newcontext.role = scontext->role;
1818 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1819 newcontext.role = tcontext->role;
1820 } else {
1821 if ((tclass == policydb->process_class) || sock)
1822 newcontext.role = scontext->role;
1823 else
1824 newcontext.role = OBJECT_R_VAL;
1825 }
1826
1827 /* Set the type to default values. */
1828 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1829 newcontext.type = scontext->type;
1830 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1831 newcontext.type = tcontext->type;
1832 } else {
1833 if ((tclass == policydb->process_class) || sock) {
1834 /* Use the type of process. */
1835 newcontext.type = scontext->type;
1836 } else {
1837 /* Use the type of the related object. */
1838 newcontext.type = tcontext->type;
1839 }
1840 }
1841
1842 /* Look for a type transition/member/change rule. */
1843 avkey.source_type = scontext->type;
1844 avkey.target_type = tcontext->type;
1845 avkey.target_class = tclass;
1846 avkey.specified = specified;
1847 avdatum = avtab_search(&policydb->te_avtab, &avkey);
1848
1849 /* If no permanent rule, also check for enabled conditional rules */
1850 if (!avdatum) {
1851 node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1852 for (; node; node = avtab_search_node_next(node, specified)) {
1853 if (node->key.specified & AVTAB_ENABLED) {
1854 avdatum = &node->datum;
1855 break;
1856 }
1857 }
1858 }
1859
1860 if (avdatum) {
1861 /* Use the type from the type transition/member/change rule. */
1862 newcontext.type = avdatum->u.data;
1863 }
1864
1865 /* if we have a objname this is a file trans check so check those rules */
1866 if (objname)
1867 filename_compute_type(policydb, &newcontext, scontext->type,
1868 tcontext->type, tclass, objname);
1869
1870 /* Check for class-specific changes. */
1871 if (specified & AVTAB_TRANSITION) {
1872 /* Look for a role transition rule. */
1873 struct role_trans_datum *rtd;
1874 struct role_trans_key rtk = {
1875 .role = scontext->role,
1876 .type = tcontext->type,
1877 .tclass = tclass,
1878 };
1879
1880 rtd = policydb_roletr_search(policydb, &rtk);
1881 if (rtd)
1882 newcontext.role = rtd->new_role;
1883 }
1884
1885 /* Set the MLS attributes.
1886 This is done last because it may allocate memory. */
1887 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1888 &newcontext, sock);
1889 if (rc)
1890 goto out_unlock;
1891
1892 /* Check the validity of the context. */
1893 if (!policydb_context_isvalid(policydb, &newcontext)) {
1894 rc = compute_sid_handle_invalid_context(state, policy, sentry,
1895 tentry, tclass,
1896 &newcontext);
1897 if (rc)
1898 goto out_unlock;
1899 }
1900 /* Obtain the sid for the context. */
1901 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1902 if (rc == -ESTALE) {
1903 rcu_read_unlock();
1904 context_destroy(&newcontext);
1905 goto retry;
1906 }
1907out_unlock:
1908 rcu_read_unlock();
1909 context_destroy(&newcontext);
1910out:
1911 return rc;
1912}
1913
1914/**
1915 * security_transition_sid - Compute the SID for a new subject/object.
1916 * @state: SELinux state
1917 * @ssid: source security identifier
1918 * @tsid: target security identifier
1919 * @tclass: target security class
1920 * @out_sid: security identifier for new subject/object
1921 *
1922 * Compute a SID to use for labeling a new subject or object in the
1923 * class @tclass based on a SID pair (@ssid, @tsid).
1924 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1925 * if insufficient memory is available, or %0 if the new SID was
1926 * computed successfully.
1927 */
1928int security_transition_sid(struct selinux_state *state,
1929 u32 ssid, u32 tsid, u16 tclass,
1930 const struct qstr *qstr, u32 *out_sid)
1931{
1932 return security_compute_sid(state, ssid, tsid, tclass,
1933 AVTAB_TRANSITION,
1934 qstr ? qstr->name : NULL, out_sid, true);
1935}
1936
1937int security_transition_sid_user(struct selinux_state *state,
1938 u32 ssid, u32 tsid, u16 tclass,
1939 const char *objname, u32 *out_sid)
1940{
1941 return security_compute_sid(state, ssid, tsid, tclass,
1942 AVTAB_TRANSITION,
1943 objname, out_sid, false);
1944}
1945
1946/**
1947 * security_member_sid - Compute the SID for member selection.
1948 * @ssid: source security identifier
1949 * @tsid: target security identifier
1950 * @tclass: target security class
1951 * @out_sid: security identifier for selected member
1952 *
1953 * Compute a SID to use when selecting a member of a polyinstantiated
1954 * object of class @tclass based on a SID pair (@ssid, @tsid).
1955 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1956 * if insufficient memory is available, or %0 if the SID was
1957 * computed successfully.
1958 */
1959int security_member_sid(struct selinux_state *state,
1960 u32 ssid,
1961 u32 tsid,
1962 u16 tclass,
1963 u32 *out_sid)
1964{
1965 return security_compute_sid(state, ssid, tsid, tclass,
1966 AVTAB_MEMBER, NULL,
1967 out_sid, false);
1968}
1969
1970/**
1971 * security_change_sid - Compute the SID for object relabeling.
1972 * @state: SELinux state
1973 * @ssid: source security identifier
1974 * @tsid: target security identifier
1975 * @tclass: target security class
1976 * @out_sid: security identifier for selected member
1977 *
1978 * Compute a SID to use for relabeling an object of class @tclass
1979 * based on a SID pair (@ssid, @tsid).
1980 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1981 * if insufficient memory is available, or %0 if the SID was
1982 * computed successfully.
1983 */
1984int security_change_sid(struct selinux_state *state,
1985 u32 ssid,
1986 u32 tsid,
1987 u16 tclass,
1988 u32 *out_sid)
1989{
1990 return security_compute_sid(state,
1991 ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1992 out_sid, false);
1993}
1994
1995static inline int convert_context_handle_invalid_context(
1996 struct selinux_state *state,
1997 struct policydb *policydb,
1998 struct context *context)
1999{
2000 char *s;
2001 u32 len;
2002
2003 if (enforcing_enabled(state))
2004 return -EINVAL;
2005
2006 if (!context_struct_to_string(policydb, context, &s, &len)) {
2007 pr_warn("SELinux: Context %s would be invalid if enforcing\n",
2008 s);
2009 kfree(s);
2010 }
2011 return 0;
2012}
2013
2014/*
2015 * Convert the values in the security context
2016 * structure `oldc' from the values specified
2017 * in the policy `p->oldp' to the values specified
2018 * in the policy `p->newp', storing the new context
2019 * in `newc'. Verify that the context is valid
2020 * under the new policy.
2021 */
2022static int convert_context(struct context *oldc, struct context *newc, void *p)
2023{
2024 struct convert_context_args *args;
2025 struct ocontext *oc;
2026 struct role_datum *role;
2027 struct type_datum *typdatum;
2028 struct user_datum *usrdatum;
2029 char *s;
2030 u32 len;
2031 int rc;
2032
2033 args = p;
2034
2035 if (oldc->str) {
2036 s = kstrdup(oldc->str, GFP_KERNEL);
2037 if (!s)
2038 return -ENOMEM;
2039
2040 rc = string_to_context_struct(args->newp, NULL, s,
2041 newc, SECSID_NULL);
2042 if (rc == -EINVAL) {
2043 /*
2044 * Retain string representation for later mapping.
2045 *
2046 * IMPORTANT: We need to copy the contents of oldc->str
2047 * back into s again because string_to_context_struct()
2048 * may have garbled it.
2049 */
2050 memcpy(s, oldc->str, oldc->len);
2051 context_init(newc);
2052 newc->str = s;
2053 newc->len = oldc->len;
2054 return 0;
2055 }
2056 kfree(s);
2057 if (rc) {
2058 /* Other error condition, e.g. ENOMEM. */
2059 pr_err("SELinux: Unable to map context %s, rc = %d.\n",
2060 oldc->str, -rc);
2061 return rc;
2062 }
2063 pr_info("SELinux: Context %s became valid (mapped).\n",
2064 oldc->str);
2065 return 0;
2066 }
2067
2068 context_init(newc);
2069
2070 /* Convert the user. */
2071 usrdatum = symtab_search(&args->newp->p_users,
2072 sym_name(args->oldp,
2073 SYM_USERS, oldc->user - 1));
2074 if (!usrdatum)
2075 goto bad;
2076 newc->user = usrdatum->value;
2077
2078 /* Convert the role. */
2079 role = symtab_search(&args->newp->p_roles,
2080 sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
2081 if (!role)
2082 goto bad;
2083 newc->role = role->value;
2084
2085 /* Convert the type. */
2086 typdatum = symtab_search(&args->newp->p_types,
2087 sym_name(args->oldp,
2088 SYM_TYPES, oldc->type - 1));
2089 if (!typdatum)
2090 goto bad;
2091 newc->type = typdatum->value;
2092
2093 /* Convert the MLS fields if dealing with MLS policies */
2094 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2095 rc = mls_convert_context(args->oldp, args->newp, oldc, newc);
2096 if (rc)
2097 goto bad;
2098 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2099 /*
2100 * Switching between non-MLS and MLS policy:
2101 * ensure that the MLS fields of the context for all
2102 * existing entries in the sidtab are filled in with a
2103 * suitable default value, likely taken from one of the
2104 * initial SIDs.
2105 */
2106 oc = args->newp->ocontexts[OCON_ISID];
2107 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2108 oc = oc->next;
2109 if (!oc) {
2110 pr_err("SELinux: unable to look up"
2111 " the initial SIDs list\n");
2112 goto bad;
2113 }
2114 rc = mls_range_set(newc, &oc->context[0].range);
2115 if (rc)
2116 goto bad;
2117 }
2118
2119 /* Check the validity of the new context. */
2120 if (!policydb_context_isvalid(args->newp, newc)) {
2121 rc = convert_context_handle_invalid_context(args->state,
2122 args->oldp,
2123 oldc);
2124 if (rc)
2125 goto bad;
2126 }
2127
2128 return 0;
2129bad:
2130 /* Map old representation to string and save it. */
2131 rc = context_struct_to_string(args->oldp, oldc, &s, &len);
2132 if (rc)
2133 return rc;
2134 context_destroy(newc);
2135 newc->str = s;
2136 newc->len = len;
2137 pr_info("SELinux: Context %s became invalid (unmapped).\n",
2138 newc->str);
2139 return 0;
2140}
2141
2142static void security_load_policycaps(struct selinux_state *state,
2143 struct selinux_policy *policy)
2144{
2145 struct policydb *p;
2146 unsigned int i;
2147 struct ebitmap_node *node;
2148
2149 p = &policy->policydb;
2150
2151 for (i = 0; i < ARRAY_SIZE(state->policycap); i++)
2152 WRITE_ONCE(state->policycap[i],
2153 ebitmap_get_bit(&p->policycaps, i));
2154
2155 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2156 pr_info("SELinux: policy capability %s=%d\n",
2157 selinux_policycap_names[i],
2158 ebitmap_get_bit(&p->policycaps, i));
2159
2160 ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2161 if (i >= ARRAY_SIZE(selinux_policycap_names))
2162 pr_info("SELinux: unknown policy capability %u\n",
2163 i);
2164 }
2165}
2166
2167static int security_preserve_bools(struct selinux_policy *oldpolicy,
2168 struct selinux_policy *newpolicy);
2169
2170static void selinux_policy_free(struct selinux_policy *policy)
2171{
2172 if (!policy)
2173 return;
2174
2175 sidtab_destroy(policy->sidtab);
2176 kfree(policy->map.mapping);
2177 policydb_destroy(&policy->policydb);
2178 kfree(policy->sidtab);
2179 kfree(policy);
2180}
2181
2182static void selinux_policy_cond_free(struct selinux_policy *policy)
2183{
2184 cond_policydb_destroy_dup(&policy->policydb);
2185 kfree(policy);
2186}
2187
2188void selinux_policy_cancel(struct selinux_state *state,
2189 struct selinux_load_state *load_state)
2190{
2191 struct selinux_policy *oldpolicy;
2192
2193 oldpolicy = rcu_dereference_protected(state->policy,
2194 lockdep_is_held(&state->policy_mutex));
2195
2196 sidtab_cancel_convert(oldpolicy->sidtab);
2197 selinux_policy_free(load_state->policy);
2198 kfree(load_state->convert_data);
2199}
2200
2201static void selinux_notify_policy_change(struct selinux_state *state,
2202 u32 seqno)
2203{
2204 /* Flush external caches and notify userspace of policy load */
2205 avc_ss_reset(state->avc, seqno);
2206 selnl_notify_policyload(seqno);
2207 selinux_status_update_policyload(state, seqno);
2208 selinux_netlbl_cache_invalidate();
2209 selinux_xfrm_notify_policyload();
2210 selinux_ima_measure_state_locked(state);
2211}
2212
2213void selinux_policy_commit(struct selinux_state *state,
2214 struct selinux_load_state *load_state)
2215{
2216 struct selinux_policy *oldpolicy, *newpolicy = load_state->policy;
2217 unsigned long flags;
2218 u32 seqno;
2219
2220 oldpolicy = rcu_dereference_protected(state->policy,
2221 lockdep_is_held(&state->policy_mutex));
2222
2223 /* If switching between different policy types, log MLS status */
2224 if (oldpolicy) {
2225 if (oldpolicy->policydb.mls_enabled && !newpolicy->policydb.mls_enabled)
2226 pr_info("SELinux: Disabling MLS support...\n");
2227 else if (!oldpolicy->policydb.mls_enabled && newpolicy->policydb.mls_enabled)
2228 pr_info("SELinux: Enabling MLS support...\n");
2229 }
2230
2231 /* Set latest granting seqno for new policy. */
2232 if (oldpolicy)
2233 newpolicy->latest_granting = oldpolicy->latest_granting + 1;
2234 else
2235 newpolicy->latest_granting = 1;
2236 seqno = newpolicy->latest_granting;
2237
2238 /* Install the new policy. */
2239 if (oldpolicy) {
2240 sidtab_freeze_begin(oldpolicy->sidtab, &flags);
2241 rcu_assign_pointer(state->policy, newpolicy);
2242 sidtab_freeze_end(oldpolicy->sidtab, &flags);
2243 } else {
2244 rcu_assign_pointer(state->policy, newpolicy);
2245 }
2246
2247 /* Load the policycaps from the new policy */
2248 security_load_policycaps(state, newpolicy);
2249
2250 if (!selinux_initialized(state)) {
2251 /*
2252 * After first policy load, the security server is
2253 * marked as initialized and ready to handle requests and
2254 * any objects created prior to policy load are then labeled.
2255 */
2256 selinux_mark_initialized(state);
2257 selinux_complete_init();
2258 }
2259
2260 /* Free the old policy */
2261 synchronize_rcu();
2262 selinux_policy_free(oldpolicy);
2263 kfree(load_state->convert_data);
2264
2265 /* Notify others of the policy change */
2266 selinux_notify_policy_change(state, seqno);
2267}
2268
2269/**
2270 * security_load_policy - Load a security policy configuration.
2271 * @state: SELinux state
2272 * @data: binary policy data
2273 * @len: length of data in bytes
2274 *
2275 * Load a new set of security policy configuration data,
2276 * validate it and convert the SID table as necessary.
2277 * This function will flush the access vector cache after
2278 * loading the new policy.
2279 */
2280int security_load_policy(struct selinux_state *state, void *data, size_t len,
2281 struct selinux_load_state *load_state)
2282{
2283 struct selinux_policy *newpolicy, *oldpolicy;
2284 struct selinux_policy_convert_data *convert_data;
2285 int rc = 0;
2286 struct policy_file file = { data, len }, *fp = &file;
2287
2288 newpolicy = kzalloc(sizeof(*newpolicy), GFP_KERNEL);
2289 if (!newpolicy)
2290 return -ENOMEM;
2291
2292 newpolicy->sidtab = kzalloc(sizeof(*newpolicy->sidtab), GFP_KERNEL);
2293 if (!newpolicy->sidtab) {
2294 rc = -ENOMEM;
2295 goto err_policy;
2296 }
2297
2298 rc = policydb_read(&newpolicy->policydb, fp);
2299 if (rc)
2300 goto err_sidtab;
2301
2302 newpolicy->policydb.len = len;
2303 rc = selinux_set_mapping(&newpolicy->policydb, secclass_map,
2304 &newpolicy->map);
2305 if (rc)
2306 goto err_policydb;
2307
2308 rc = policydb_load_isids(&newpolicy->policydb, newpolicy->sidtab);
2309 if (rc) {
2310 pr_err("SELinux: unable to load the initial SIDs\n");
2311 goto err_mapping;
2312 }
2313
2314 if (!selinux_initialized(state)) {
2315 /* First policy load, so no need to preserve state from old policy */
2316 load_state->policy = newpolicy;
2317 load_state->convert_data = NULL;
2318 return 0;
2319 }
2320
2321 oldpolicy = rcu_dereference_protected(state->policy,
2322 lockdep_is_held(&state->policy_mutex));
2323
2324 /* Preserve active boolean values from the old policy */
2325 rc = security_preserve_bools(oldpolicy, newpolicy);
2326 if (rc) {
2327 pr_err("SELinux: unable to preserve booleans\n");
2328 goto err_free_isids;
2329 }
2330
2331 convert_data = kmalloc(sizeof(*convert_data), GFP_KERNEL);
2332 if (!convert_data) {
2333 rc = -ENOMEM;
2334 goto err_free_isids;
2335 }
2336
2337 /*
2338 * Convert the internal representations of contexts
2339 * in the new SID table.
2340 */
2341 convert_data->args.state = state;
2342 convert_data->args.oldp = &oldpolicy->policydb;
2343 convert_data->args.newp = &newpolicy->policydb;
2344
2345 convert_data->sidtab_params.func = convert_context;
2346 convert_data->sidtab_params.args = &convert_data->args;
2347 convert_data->sidtab_params.target = newpolicy->sidtab;
2348
2349 rc = sidtab_convert(oldpolicy->sidtab, &convert_data->sidtab_params);
2350 if (rc) {
2351 pr_err("SELinux: unable to convert the internal"
2352 " representation of contexts in the new SID"
2353 " table\n");
2354 goto err_free_convert_data;
2355 }
2356
2357 load_state->policy = newpolicy;
2358 load_state->convert_data = convert_data;
2359 return 0;
2360
2361err_free_convert_data:
2362 kfree(convert_data);
2363err_free_isids:
2364 sidtab_destroy(newpolicy->sidtab);
2365err_mapping:
2366 kfree(newpolicy->map.mapping);
2367err_policydb:
2368 policydb_destroy(&newpolicy->policydb);
2369err_sidtab:
2370 kfree(newpolicy->sidtab);
2371err_policy:
2372 kfree(newpolicy);
2373
2374 return rc;
2375}
2376
2377/**
2378 * security_port_sid - Obtain the SID for a port.
2379 * @state: SELinux state
2380 * @protocol: protocol number
2381 * @port: port number
2382 * @out_sid: security identifier
2383 */
2384int security_port_sid(struct selinux_state *state,
2385 u8 protocol, u16 port, u32 *out_sid)
2386{
2387 struct selinux_policy *policy;
2388 struct policydb *policydb;
2389 struct sidtab *sidtab;
2390 struct ocontext *c;
2391 int rc;
2392
2393 if (!selinux_initialized(state)) {
2394 *out_sid = SECINITSID_PORT;
2395 return 0;
2396 }
2397
2398retry:
2399 rc = 0;
2400 rcu_read_lock();
2401 policy = rcu_dereference(state->policy);
2402 policydb = &policy->policydb;
2403 sidtab = policy->sidtab;
2404
2405 c = policydb->ocontexts[OCON_PORT];
2406 while (c) {
2407 if (c->u.port.protocol == protocol &&
2408 c->u.port.low_port <= port &&
2409 c->u.port.high_port >= port)
2410 break;
2411 c = c->next;
2412 }
2413
2414 if (c) {
2415 if (!c->sid[0]) {
2416 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2417 &c->sid[0]);
2418 if (rc == -ESTALE) {
2419 rcu_read_unlock();
2420 goto retry;
2421 }
2422 if (rc)
2423 goto out;
2424 }
2425 *out_sid = c->sid[0];
2426 } else {
2427 *out_sid = SECINITSID_PORT;
2428 }
2429
2430out:
2431 rcu_read_unlock();
2432 return rc;
2433}
2434
2435/**
2436 * security_ib_pkey_sid - Obtain the SID for a pkey.
2437 * @state: SELinux state
2438 * @subnet_prefix: Subnet Prefix
2439 * @pkey_num: pkey number
2440 * @out_sid: security identifier
2441 */
2442int security_ib_pkey_sid(struct selinux_state *state,
2443 u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2444{
2445 struct selinux_policy *policy;
2446 struct policydb *policydb;
2447 struct sidtab *sidtab;
2448 struct ocontext *c;
2449 int rc;
2450
2451 if (!selinux_initialized(state)) {
2452 *out_sid = SECINITSID_UNLABELED;
2453 return 0;
2454 }
2455
2456retry:
2457 rc = 0;
2458 rcu_read_lock();
2459 policy = rcu_dereference(state->policy);
2460 policydb = &policy->policydb;
2461 sidtab = policy->sidtab;
2462
2463 c = policydb->ocontexts[OCON_IBPKEY];
2464 while (c) {
2465 if (c->u.ibpkey.low_pkey <= pkey_num &&
2466 c->u.ibpkey.high_pkey >= pkey_num &&
2467 c->u.ibpkey.subnet_prefix == subnet_prefix)
2468 break;
2469
2470 c = c->next;
2471 }
2472
2473 if (c) {
2474 if (!c->sid[0]) {
2475 rc = sidtab_context_to_sid(sidtab,
2476 &c->context[0],
2477 &c->sid[0]);
2478 if (rc == -ESTALE) {
2479 rcu_read_unlock();
2480 goto retry;
2481 }
2482 if (rc)
2483 goto out;
2484 }
2485 *out_sid = c->sid[0];
2486 } else
2487 *out_sid = SECINITSID_UNLABELED;
2488
2489out:
2490 rcu_read_unlock();
2491 return rc;
2492}
2493
2494/**
2495 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2496 * @state: SELinux state
2497 * @dev_name: device name
2498 * @port: port number
2499 * @out_sid: security identifier
2500 */
2501int security_ib_endport_sid(struct selinux_state *state,
2502 const char *dev_name, u8 port_num, u32 *out_sid)
2503{
2504 struct selinux_policy *policy;
2505 struct policydb *policydb;
2506 struct sidtab *sidtab;
2507 struct ocontext *c;
2508 int rc;
2509
2510 if (!selinux_initialized(state)) {
2511 *out_sid = SECINITSID_UNLABELED;
2512 return 0;
2513 }
2514
2515retry:
2516 rc = 0;
2517 rcu_read_lock();
2518 policy = rcu_dereference(state->policy);
2519 policydb = &policy->policydb;
2520 sidtab = policy->sidtab;
2521
2522 c = policydb->ocontexts[OCON_IBENDPORT];
2523 while (c) {
2524 if (c->u.ibendport.port == port_num &&
2525 !strncmp(c->u.ibendport.dev_name,
2526 dev_name,
2527 IB_DEVICE_NAME_MAX))
2528 break;
2529
2530 c = c->next;
2531 }
2532
2533 if (c) {
2534 if (!c->sid[0]) {
2535 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2536 &c->sid[0]);
2537 if (rc == -ESTALE) {
2538 rcu_read_unlock();
2539 goto retry;
2540 }
2541 if (rc)
2542 goto out;
2543 }
2544 *out_sid = c->sid[0];
2545 } else
2546 *out_sid = SECINITSID_UNLABELED;
2547
2548out:
2549 rcu_read_unlock();
2550 return rc;
2551}
2552
2553/**
2554 * security_netif_sid - Obtain the SID for a network interface.
2555 * @state: SELinux state
2556 * @name: interface name
2557 * @if_sid: interface SID
2558 */
2559int security_netif_sid(struct selinux_state *state,
2560 char *name, u32 *if_sid)
2561{
2562 struct selinux_policy *policy;
2563 struct policydb *policydb;
2564 struct sidtab *sidtab;
2565 int rc;
2566 struct ocontext *c;
2567
2568 if (!selinux_initialized(state)) {
2569 *if_sid = SECINITSID_NETIF;
2570 return 0;
2571 }
2572
2573retry:
2574 rc = 0;
2575 rcu_read_lock();
2576 policy = rcu_dereference(state->policy);
2577 policydb = &policy->policydb;
2578 sidtab = policy->sidtab;
2579
2580 c = policydb->ocontexts[OCON_NETIF];
2581 while (c) {
2582 if (strcmp(name, c->u.name) == 0)
2583 break;
2584 c = c->next;
2585 }
2586
2587 if (c) {
2588 if (!c->sid[0] || !c->sid[1]) {
2589 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2590 &c->sid[0]);
2591 if (rc == -ESTALE) {
2592 rcu_read_unlock();
2593 goto retry;
2594 }
2595 if (rc)
2596 goto out;
2597 rc = sidtab_context_to_sid(sidtab, &c->context[1],
2598 &c->sid[1]);
2599 if (rc == -ESTALE) {
2600 rcu_read_unlock();
2601 goto retry;
2602 }
2603 if (rc)
2604 goto out;
2605 }
2606 *if_sid = c->sid[0];
2607 } else
2608 *if_sid = SECINITSID_NETIF;
2609
2610out:
2611 rcu_read_unlock();
2612 return rc;
2613}
2614
2615static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2616{
2617 int i, fail = 0;
2618
2619 for (i = 0; i < 4; i++)
2620 if (addr[i] != (input[i] & mask[i])) {
2621 fail = 1;
2622 break;
2623 }
2624
2625 return !fail;
2626}
2627
2628/**
2629 * security_node_sid - Obtain the SID for a node (host).
2630 * @state: SELinux state
2631 * @domain: communication domain aka address family
2632 * @addrp: address
2633 * @addrlen: address length in bytes
2634 * @out_sid: security identifier
2635 */
2636int security_node_sid(struct selinux_state *state,
2637 u16 domain,
2638 void *addrp,
2639 u32 addrlen,
2640 u32 *out_sid)
2641{
2642 struct selinux_policy *policy;
2643 struct policydb *policydb;
2644 struct sidtab *sidtab;
2645 int rc;
2646 struct ocontext *c;
2647
2648 if (!selinux_initialized(state)) {
2649 *out_sid = SECINITSID_NODE;
2650 return 0;
2651 }
2652
2653retry:
2654 rcu_read_lock();
2655 policy = rcu_dereference(state->policy);
2656 policydb = &policy->policydb;
2657 sidtab = policy->sidtab;
2658
2659 switch (domain) {
2660 case AF_INET: {
2661 u32 addr;
2662
2663 rc = -EINVAL;
2664 if (addrlen != sizeof(u32))
2665 goto out;
2666
2667 addr = *((u32 *)addrp);
2668
2669 c = policydb->ocontexts[OCON_NODE];
2670 while (c) {
2671 if (c->u.node.addr == (addr & c->u.node.mask))
2672 break;
2673 c = c->next;
2674 }
2675 break;
2676 }
2677
2678 case AF_INET6:
2679 rc = -EINVAL;
2680 if (addrlen != sizeof(u64) * 2)
2681 goto out;
2682 c = policydb->ocontexts[OCON_NODE6];
2683 while (c) {
2684 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2685 c->u.node6.mask))
2686 break;
2687 c = c->next;
2688 }
2689 break;
2690
2691 default:
2692 rc = 0;
2693 *out_sid = SECINITSID_NODE;
2694 goto out;
2695 }
2696
2697 if (c) {
2698 if (!c->sid[0]) {
2699 rc = sidtab_context_to_sid(sidtab,
2700 &c->context[0],
2701 &c->sid[0]);
2702 if (rc == -ESTALE) {
2703 rcu_read_unlock();
2704 goto retry;
2705 }
2706 if (rc)
2707 goto out;
2708 }
2709 *out_sid = c->sid[0];
2710 } else {
2711 *out_sid = SECINITSID_NODE;
2712 }
2713
2714 rc = 0;
2715out:
2716 rcu_read_unlock();
2717 return rc;
2718}
2719
2720#define SIDS_NEL 25
2721
2722/**
2723 * security_get_user_sids - Obtain reachable SIDs for a user.
2724 * @state: SELinux state
2725 * @fromsid: starting SID
2726 * @username: username
2727 * @sids: array of reachable SIDs for user
2728 * @nel: number of elements in @sids
2729 *
2730 * Generate the set of SIDs for legal security contexts
2731 * for a given user that can be reached by @fromsid.
2732 * Set *@sids to point to a dynamically allocated
2733 * array containing the set of SIDs. Set *@nel to the
2734 * number of elements in the array.
2735 */
2736
2737int security_get_user_sids(struct selinux_state *state,
2738 u32 fromsid,
2739 char *username,
2740 u32 **sids,
2741 u32 *nel)
2742{
2743 struct selinux_policy *policy;
2744 struct policydb *policydb;
2745 struct sidtab *sidtab;
2746 struct context *fromcon, usercon;
2747 u32 *mysids = NULL, *mysids2, sid;
2748 u32 i, j, mynel, maxnel = SIDS_NEL;
2749 struct user_datum *user;
2750 struct role_datum *role;
2751 struct ebitmap_node *rnode, *tnode;
2752 int rc;
2753
2754 *sids = NULL;
2755 *nel = 0;
2756
2757 if (!selinux_initialized(state))
2758 return 0;
2759
2760 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_KERNEL);
2761 if (!mysids)
2762 return -ENOMEM;
2763
2764retry:
2765 mynel = 0;
2766 rcu_read_lock();
2767 policy = rcu_dereference(state->policy);
2768 policydb = &policy->policydb;
2769 sidtab = policy->sidtab;
2770
2771 context_init(&usercon);
2772
2773 rc = -EINVAL;
2774 fromcon = sidtab_search(sidtab, fromsid);
2775 if (!fromcon)
2776 goto out_unlock;
2777
2778 rc = -EINVAL;
2779 user = symtab_search(&policydb->p_users, username);
2780 if (!user)
2781 goto out_unlock;
2782
2783 usercon.user = user->value;
2784
2785 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2786 role = policydb->role_val_to_struct[i];
2787 usercon.role = i + 1;
2788 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2789 usercon.type = j + 1;
2790
2791 if (mls_setup_user_range(policydb, fromcon, user,
2792 &usercon))
2793 continue;
2794
2795 rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2796 if (rc == -ESTALE) {
2797 rcu_read_unlock();
2798 goto retry;
2799 }
2800 if (rc)
2801 goto out_unlock;
2802 if (mynel < maxnel) {
2803 mysids[mynel++] = sid;
2804 } else {
2805 rc = -ENOMEM;
2806 maxnel += SIDS_NEL;
2807 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2808 if (!mysids2)
2809 goto out_unlock;
2810 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2811 kfree(mysids);
2812 mysids = mysids2;
2813 mysids[mynel++] = sid;
2814 }
2815 }
2816 }
2817 rc = 0;
2818out_unlock:
2819 rcu_read_unlock();
2820 if (rc || !mynel) {
2821 kfree(mysids);
2822 return rc;
2823 }
2824
2825 rc = -ENOMEM;
2826 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2827 if (!mysids2) {
2828 kfree(mysids);
2829 return rc;
2830 }
2831 for (i = 0, j = 0; i < mynel; i++) {
2832 struct av_decision dummy_avd;
2833 rc = avc_has_perm_noaudit(state,
2834 fromsid, mysids[i],
2835 SECCLASS_PROCESS, /* kernel value */
2836 PROCESS__TRANSITION, AVC_STRICT,
2837 &dummy_avd);
2838 if (!rc)
2839 mysids2[j++] = mysids[i];
2840 cond_resched();
2841 }
2842 kfree(mysids);
2843 *sids = mysids2;
2844 *nel = j;
2845 return 0;
2846}
2847
2848/**
2849 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2850 * @fstype: filesystem type
2851 * @path: path from root of mount
2852 * @sclass: file security class
2853 * @sid: SID for path
2854 *
2855 * Obtain a SID to use for a file in a filesystem that
2856 * cannot support xattr or use a fixed labeling behavior like
2857 * transition SIDs or task SIDs.
2858 *
2859 * WARNING: This function may return -ESTALE, indicating that the caller
2860 * must retry the operation after re-acquiring the policy pointer!
2861 */
2862static inline int __security_genfs_sid(struct selinux_policy *policy,
2863 const char *fstype,
2864 char *path,
2865 u16 orig_sclass,
2866 u32 *sid)
2867{
2868 struct policydb *policydb = &policy->policydb;
2869 struct sidtab *sidtab = policy->sidtab;
2870 int len;
2871 u16 sclass;
2872 struct genfs *genfs;
2873 struct ocontext *c;
2874 int rc, cmp = 0;
2875
2876 while (path[0] == '/' && path[1] == '/')
2877 path++;
2878
2879 sclass = unmap_class(&policy->map, orig_sclass);
2880 *sid = SECINITSID_UNLABELED;
2881
2882 for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2883 cmp = strcmp(fstype, genfs->fstype);
2884 if (cmp <= 0)
2885 break;
2886 }
2887
2888 rc = -ENOENT;
2889 if (!genfs || cmp)
2890 goto out;
2891
2892 for (c = genfs->head; c; c = c->next) {
2893 len = strlen(c->u.name);
2894 if ((!c->v.sclass || sclass == c->v.sclass) &&
2895 (strncmp(c->u.name, path, len) == 0))
2896 break;
2897 }
2898
2899 rc = -ENOENT;
2900 if (!c)
2901 goto out;
2902
2903 if (!c->sid[0]) {
2904 rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]);
2905 if (rc)
2906 goto out;
2907 }
2908
2909 *sid = c->sid[0];
2910 rc = 0;
2911out:
2912 return rc;
2913}
2914
2915/**
2916 * security_genfs_sid - Obtain a SID for a file in a filesystem
2917 * @state: SELinux state
2918 * @fstype: filesystem type
2919 * @path: path from root of mount
2920 * @sclass: file security class
2921 * @sid: SID for path
2922 *
2923 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2924 * it afterward.
2925 */
2926int security_genfs_sid(struct selinux_state *state,
2927 const char *fstype,
2928 char *path,
2929 u16 orig_sclass,
2930 u32 *sid)
2931{
2932 struct selinux_policy *policy;
2933 int retval;
2934
2935 if (!selinux_initialized(state)) {
2936 *sid = SECINITSID_UNLABELED;
2937 return 0;
2938 }
2939
2940 do {
2941 rcu_read_lock();
2942 policy = rcu_dereference(state->policy);
2943 retval = __security_genfs_sid(policy, fstype, path,
2944 orig_sclass, sid);
2945 rcu_read_unlock();
2946 } while (retval == -ESTALE);
2947 return retval;
2948}
2949
2950int selinux_policy_genfs_sid(struct selinux_policy *policy,
2951 const char *fstype,
2952 char *path,
2953 u16 orig_sclass,
2954 u32 *sid)
2955{
2956 /* no lock required, policy is not yet accessible by other threads */
2957 return __security_genfs_sid(policy, fstype, path, orig_sclass, sid);
2958}
2959
2960/**
2961 * security_fs_use - Determine how to handle labeling for a filesystem.
2962 * @state: SELinux state
2963 * @sb: superblock in question
2964 */
2965int security_fs_use(struct selinux_state *state, struct super_block *sb)
2966{
2967 struct selinux_policy *policy;
2968 struct policydb *policydb;
2969 struct sidtab *sidtab;
2970 int rc;
2971 struct ocontext *c;
2972 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2973 const char *fstype = sb->s_type->name;
2974
2975 if (!selinux_initialized(state)) {
2976 sbsec->behavior = SECURITY_FS_USE_NONE;
2977 sbsec->sid = SECINITSID_UNLABELED;
2978 return 0;
2979 }
2980
2981retry:
2982 rc = 0;
2983 rcu_read_lock();
2984 policy = rcu_dereference(state->policy);
2985 policydb = &policy->policydb;
2986 sidtab = policy->sidtab;
2987
2988 c = policydb->ocontexts[OCON_FSUSE];
2989 while (c) {
2990 if (strcmp(fstype, c->u.name) == 0)
2991 break;
2992 c = c->next;
2993 }
2994
2995 if (c) {
2996 sbsec->behavior = c->v.behavior;
2997 if (!c->sid[0]) {
2998 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2999 &c->sid[0]);
3000 if (rc == -ESTALE) {
3001 rcu_read_unlock();
3002 goto retry;
3003 }
3004 if (rc)
3005 goto out;
3006 }
3007 sbsec->sid = c->sid[0];
3008 } else {
3009 rc = __security_genfs_sid(policy, fstype, "/",
3010 SECCLASS_DIR, &sbsec->sid);
3011 if (rc == -ESTALE) {
3012 rcu_read_unlock();
3013 goto retry;
3014 }
3015 if (rc) {
3016 sbsec->behavior = SECURITY_FS_USE_NONE;
3017 rc = 0;
3018 } else {
3019 sbsec->behavior = SECURITY_FS_USE_GENFS;
3020 }
3021 }
3022
3023out:
3024 rcu_read_unlock();
3025 return rc;
3026}
3027
3028int security_get_bools(struct selinux_policy *policy,
3029 u32 *len, char ***names, int **values)
3030{
3031 struct policydb *policydb;
3032 u32 i;
3033 int rc;
3034
3035 policydb = &policy->policydb;
3036
3037 *names = NULL;
3038 *values = NULL;
3039
3040 rc = 0;
3041 *len = policydb->p_bools.nprim;
3042 if (!*len)
3043 goto out;
3044
3045 rc = -ENOMEM;
3046 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
3047 if (!*names)
3048 goto err;
3049
3050 rc = -ENOMEM;
3051 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
3052 if (!*values)
3053 goto err;
3054
3055 for (i = 0; i < *len; i++) {
3056 (*values)[i] = policydb->bool_val_to_struct[i]->state;
3057
3058 rc = -ENOMEM;
3059 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
3060 GFP_ATOMIC);
3061 if (!(*names)[i])
3062 goto err;
3063 }
3064 rc = 0;
3065out:
3066 return rc;
3067err:
3068 if (*names) {
3069 for (i = 0; i < *len; i++)
3070 kfree((*names)[i]);
3071 kfree(*names);
3072 }
3073 kfree(*values);
3074 *len = 0;
3075 *names = NULL;
3076 *values = NULL;
3077 goto out;
3078}
3079
3080
3081int security_set_bools(struct selinux_state *state, u32 len, int *values)
3082{
3083 struct selinux_policy *newpolicy, *oldpolicy;
3084 int rc;
3085 u32 i, seqno = 0;
3086
3087 if (!selinux_initialized(state))
3088 return -EINVAL;
3089
3090 oldpolicy = rcu_dereference_protected(state->policy,
3091 lockdep_is_held(&state->policy_mutex));
3092
3093 /* Consistency check on number of booleans, should never fail */
3094 if (WARN_ON(len != oldpolicy->policydb.p_bools.nprim))
3095 return -EINVAL;
3096
3097 newpolicy = kmemdup(oldpolicy, sizeof(*newpolicy), GFP_KERNEL);
3098 if (!newpolicy)
3099 return -ENOMEM;
3100
3101 /*
3102 * Deep copy only the parts of the policydb that might be
3103 * modified as a result of changing booleans.
3104 */
3105 rc = cond_policydb_dup(&newpolicy->policydb, &oldpolicy->policydb);
3106 if (rc) {
3107 kfree(newpolicy);
3108 return -ENOMEM;
3109 }
3110
3111 /* Update the boolean states in the copy */
3112 for (i = 0; i < len; i++) {
3113 int new_state = !!values[i];
3114 int old_state = newpolicy->policydb.bool_val_to_struct[i]->state;
3115
3116 if (new_state != old_state) {
3117 audit_log(audit_context(), GFP_ATOMIC,
3118 AUDIT_MAC_CONFIG_CHANGE,
3119 "bool=%s val=%d old_val=%d auid=%u ses=%u",
3120 sym_name(&newpolicy->policydb, SYM_BOOLS, i),
3121 new_state,
3122 old_state,
3123 from_kuid(&init_user_ns, audit_get_loginuid(current)),
3124 audit_get_sessionid(current));
3125 newpolicy->policydb.bool_val_to_struct[i]->state = new_state;
3126 }
3127 }
3128
3129 /* Re-evaluate the conditional rules in the copy */
3130 evaluate_cond_nodes(&newpolicy->policydb);
3131
3132 /* Set latest granting seqno for new policy */
3133 newpolicy->latest_granting = oldpolicy->latest_granting + 1;
3134 seqno = newpolicy->latest_granting;
3135
3136 /* Install the new policy */
3137 rcu_assign_pointer(state->policy, newpolicy);
3138
3139 /*
3140 * Free the conditional portions of the old policydb
3141 * that were copied for the new policy, and the oldpolicy
3142 * structure itself but not what it references.
3143 */
3144 synchronize_rcu();
3145 selinux_policy_cond_free(oldpolicy);
3146
3147 /* Notify others of the policy change */
3148 selinux_notify_policy_change(state, seqno);
3149 return 0;
3150}
3151
3152int security_get_bool_value(struct selinux_state *state,
3153 u32 index)
3154{
3155 struct selinux_policy *policy;
3156 struct policydb *policydb;
3157 int rc;
3158 u32 len;
3159
3160 if (!selinux_initialized(state))
3161 return 0;
3162
3163 rcu_read_lock();
3164 policy = rcu_dereference(state->policy);
3165 policydb = &policy->policydb;
3166
3167 rc = -EFAULT;
3168 len = policydb->p_bools.nprim;
3169 if (index >= len)
3170 goto out;
3171
3172 rc = policydb->bool_val_to_struct[index]->state;
3173out:
3174 rcu_read_unlock();
3175 return rc;
3176}
3177
3178static int security_preserve_bools(struct selinux_policy *oldpolicy,
3179 struct selinux_policy *newpolicy)
3180{
3181 int rc, *bvalues = NULL;
3182 char **bnames = NULL;
3183 struct cond_bool_datum *booldatum;
3184 u32 i, nbools = 0;
3185
3186 rc = security_get_bools(oldpolicy, &nbools, &bnames, &bvalues);
3187 if (rc)
3188 goto out;
3189 for (i = 0; i < nbools; i++) {
3190 booldatum = symtab_search(&newpolicy->policydb.p_bools,
3191 bnames[i]);
3192 if (booldatum)
3193 booldatum->state = bvalues[i];
3194 }
3195 evaluate_cond_nodes(&newpolicy->policydb);
3196
3197out:
3198 if (bnames) {
3199 for (i = 0; i < nbools; i++)
3200 kfree(bnames[i]);
3201 }
3202 kfree(bnames);
3203 kfree(bvalues);
3204 return rc;
3205}
3206
3207/*
3208 * security_sid_mls_copy() - computes a new sid based on the given
3209 * sid and the mls portion of mls_sid.
3210 */
3211int security_sid_mls_copy(struct selinux_state *state,
3212 u32 sid, u32 mls_sid, u32 *new_sid)
3213{
3214 struct selinux_policy *policy;
3215 struct policydb *policydb;
3216 struct sidtab *sidtab;
3217 struct context *context1;
3218 struct context *context2;
3219 struct context newcon;
3220 char *s;
3221 u32 len;
3222 int rc;
3223
3224 if (!selinux_initialized(state)) {
3225 *new_sid = sid;
3226 return 0;
3227 }
3228
3229retry:
3230 rc = 0;
3231 context_init(&newcon);
3232
3233 rcu_read_lock();
3234 policy = rcu_dereference(state->policy);
3235 policydb = &policy->policydb;
3236 sidtab = policy->sidtab;
3237
3238 if (!policydb->mls_enabled) {
3239 *new_sid = sid;
3240 goto out_unlock;
3241 }
3242
3243 rc = -EINVAL;
3244 context1 = sidtab_search(sidtab, sid);
3245 if (!context1) {
3246 pr_err("SELinux: %s: unrecognized SID %d\n",
3247 __func__, sid);
3248 goto out_unlock;
3249 }
3250
3251 rc = -EINVAL;
3252 context2 = sidtab_search(sidtab, mls_sid);
3253 if (!context2) {
3254 pr_err("SELinux: %s: unrecognized SID %d\n",
3255 __func__, mls_sid);
3256 goto out_unlock;
3257 }
3258
3259 newcon.user = context1->user;
3260 newcon.role = context1->role;
3261 newcon.type = context1->type;
3262 rc = mls_context_cpy(&newcon, context2);
3263 if (rc)
3264 goto out_unlock;
3265
3266 /* Check the validity of the new context. */
3267 if (!policydb_context_isvalid(policydb, &newcon)) {
3268 rc = convert_context_handle_invalid_context(state, policydb,
3269 &newcon);
3270 if (rc) {
3271 if (!context_struct_to_string(policydb, &newcon, &s,
3272 &len)) {
3273 struct audit_buffer *ab;
3274
3275 ab = audit_log_start(audit_context(),
3276 GFP_ATOMIC,
3277 AUDIT_SELINUX_ERR);
3278 audit_log_format(ab,
3279 "op=security_sid_mls_copy invalid_context=");
3280 /* don't record NUL with untrusted strings */
3281 audit_log_n_untrustedstring(ab, s, len - 1);
3282 audit_log_end(ab);
3283 kfree(s);
3284 }
3285 goto out_unlock;
3286 }
3287 }
3288 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3289 if (rc == -ESTALE) {
3290 rcu_read_unlock();
3291 context_destroy(&newcon);
3292 goto retry;
3293 }
3294out_unlock:
3295 rcu_read_unlock();
3296 context_destroy(&newcon);
3297 return rc;
3298}
3299
3300/**
3301 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3302 * @state: SELinux state
3303 * @nlbl_sid: NetLabel SID
3304 * @nlbl_type: NetLabel labeling protocol type
3305 * @xfrm_sid: XFRM SID
3306 *
3307 * Description:
3308 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3309 * resolved into a single SID it is returned via @peer_sid and the function
3310 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3311 * returns a negative value. A table summarizing the behavior is below:
3312 *
3313 * | function return | @sid
3314 * ------------------------------+-----------------+-----------------
3315 * no peer labels | 0 | SECSID_NULL
3316 * single peer label | 0 | <peer_label>
3317 * multiple, consistent labels | 0 | <peer_label>
3318 * multiple, inconsistent labels | -<errno> | SECSID_NULL
3319 *
3320 */
3321int security_net_peersid_resolve(struct selinux_state *state,
3322 u32 nlbl_sid, u32 nlbl_type,
3323 u32 xfrm_sid,
3324 u32 *peer_sid)
3325{
3326 struct selinux_policy *policy;
3327 struct policydb *policydb;
3328 struct sidtab *sidtab;
3329 int rc;
3330 struct context *nlbl_ctx;
3331 struct context *xfrm_ctx;
3332
3333 *peer_sid = SECSID_NULL;
3334
3335 /* handle the common (which also happens to be the set of easy) cases
3336 * right away, these two if statements catch everything involving a
3337 * single or absent peer SID/label */
3338 if (xfrm_sid == SECSID_NULL) {
3339 *peer_sid = nlbl_sid;
3340 return 0;
3341 }
3342 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3343 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3344 * is present */
3345 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3346 *peer_sid = xfrm_sid;
3347 return 0;
3348 }
3349
3350 if (!selinux_initialized(state))
3351 return 0;
3352
3353 rcu_read_lock();
3354 policy = rcu_dereference(state->policy);
3355 policydb = &policy->policydb;
3356 sidtab = policy->sidtab;
3357
3358 /*
3359 * We don't need to check initialized here since the only way both
3360 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3361 * security server was initialized and state->initialized was true.
3362 */
3363 if (!policydb->mls_enabled) {
3364 rc = 0;
3365 goto out;
3366 }
3367
3368 rc = -EINVAL;
3369 nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3370 if (!nlbl_ctx) {
3371 pr_err("SELinux: %s: unrecognized SID %d\n",
3372 __func__, nlbl_sid);
3373 goto out;
3374 }
3375 rc = -EINVAL;
3376 xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3377 if (!xfrm_ctx) {
3378 pr_err("SELinux: %s: unrecognized SID %d\n",
3379 __func__, xfrm_sid);
3380 goto out;
3381 }
3382 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3383 if (rc)
3384 goto out;
3385
3386 /* at present NetLabel SIDs/labels really only carry MLS
3387 * information so if the MLS portion of the NetLabel SID
3388 * matches the MLS portion of the labeled XFRM SID/label
3389 * then pass along the XFRM SID as it is the most
3390 * expressive */
3391 *peer_sid = xfrm_sid;
3392out:
3393 rcu_read_unlock();
3394 return rc;
3395}
3396
3397static int get_classes_callback(void *k, void *d, void *args)
3398{
3399 struct class_datum *datum = d;
3400 char *name = k, **classes = args;
3401 int value = datum->value - 1;
3402
3403 classes[value] = kstrdup(name, GFP_ATOMIC);
3404 if (!classes[value])
3405 return -ENOMEM;
3406
3407 return 0;
3408}
3409
3410int security_get_classes(struct selinux_policy *policy,
3411 char ***classes, int *nclasses)
3412{
3413 struct policydb *policydb;
3414 int rc;
3415
3416 policydb = &policy->policydb;
3417
3418 rc = -ENOMEM;
3419 *nclasses = policydb->p_classes.nprim;
3420 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3421 if (!*classes)
3422 goto out;
3423
3424 rc = hashtab_map(&policydb->p_classes.table, get_classes_callback,
3425 *classes);
3426 if (rc) {
3427 int i;
3428 for (i = 0; i < *nclasses; i++)
3429 kfree((*classes)[i]);
3430 kfree(*classes);
3431 }
3432
3433out:
3434 return rc;
3435}
3436
3437static int get_permissions_callback(void *k, void *d, void *args)
3438{
3439 struct perm_datum *datum = d;
3440 char *name = k, **perms = args;
3441 int value = datum->value - 1;
3442
3443 perms[value] = kstrdup(name, GFP_ATOMIC);
3444 if (!perms[value])
3445 return -ENOMEM;
3446
3447 return 0;
3448}
3449
3450int security_get_permissions(struct selinux_policy *policy,
3451 char *class, char ***perms, int *nperms)
3452{
3453 struct policydb *policydb;
3454 int rc, i;
3455 struct class_datum *match;
3456
3457 policydb = &policy->policydb;
3458
3459 rc = -EINVAL;
3460 match = symtab_search(&policydb->p_classes, class);
3461 if (!match) {
3462 pr_err("SELinux: %s: unrecognized class %s\n",
3463 __func__, class);
3464 goto out;
3465 }
3466
3467 rc = -ENOMEM;
3468 *nperms = match->permissions.nprim;
3469 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3470 if (!*perms)
3471 goto out;
3472
3473 if (match->comdatum) {
3474 rc = hashtab_map(&match->comdatum->permissions.table,
3475 get_permissions_callback, *perms);
3476 if (rc)
3477 goto err;
3478 }
3479
3480 rc = hashtab_map(&match->permissions.table, get_permissions_callback,
3481 *perms);
3482 if (rc)
3483 goto err;
3484
3485out:
3486 return rc;
3487
3488err:
3489 for (i = 0; i < *nperms; i++)
3490 kfree((*perms)[i]);
3491 kfree(*perms);
3492 return rc;
3493}
3494
3495int security_get_reject_unknown(struct selinux_state *state)
3496{
3497 struct selinux_policy *policy;
3498 int value;
3499
3500 if (!selinux_initialized(state))
3501 return 0;
3502
3503 rcu_read_lock();
3504 policy = rcu_dereference(state->policy);
3505 value = policy->policydb.reject_unknown;
3506 rcu_read_unlock();
3507 return value;
3508}
3509
3510int security_get_allow_unknown(struct selinux_state *state)
3511{
3512 struct selinux_policy *policy;
3513 int value;
3514
3515 if (!selinux_initialized(state))
3516 return 0;
3517
3518 rcu_read_lock();
3519 policy = rcu_dereference(state->policy);
3520 value = policy->policydb.allow_unknown;
3521 rcu_read_unlock();
3522 return value;
3523}
3524
3525/**
3526 * security_policycap_supported - Check for a specific policy capability
3527 * @state: SELinux state
3528 * @req_cap: capability
3529 *
3530 * Description:
3531 * This function queries the currently loaded policy to see if it supports the
3532 * capability specified by @req_cap. Returns true (1) if the capability is
3533 * supported, false (0) if it isn't supported.
3534 *
3535 */
3536int security_policycap_supported(struct selinux_state *state,
3537 unsigned int req_cap)
3538{
3539 struct selinux_policy *policy;
3540 int rc;
3541
3542 if (!selinux_initialized(state))
3543 return 0;
3544
3545 rcu_read_lock();
3546 policy = rcu_dereference(state->policy);
3547 rc = ebitmap_get_bit(&policy->policydb.policycaps, req_cap);
3548 rcu_read_unlock();
3549
3550 return rc;
3551}
3552
3553struct selinux_audit_rule {
3554 u32 au_seqno;
3555 struct context au_ctxt;
3556};
3557
3558void selinux_audit_rule_free(void *vrule)
3559{
3560 struct selinux_audit_rule *rule = vrule;
3561
3562 if (rule) {
3563 context_destroy(&rule->au_ctxt);
3564 kfree(rule);
3565 }
3566}
3567
3568int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3569{
3570 struct selinux_state *state = &selinux_state;
3571 struct selinux_policy *policy;
3572 struct policydb *policydb;
3573 struct selinux_audit_rule *tmprule;
3574 struct role_datum *roledatum;
3575 struct type_datum *typedatum;
3576 struct user_datum *userdatum;
3577 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3578 int rc = 0;
3579
3580 *rule = NULL;
3581
3582 if (!selinux_initialized(state))
3583 return -EOPNOTSUPP;
3584
3585 switch (field) {
3586 case AUDIT_SUBJ_USER:
3587 case AUDIT_SUBJ_ROLE:
3588 case AUDIT_SUBJ_TYPE:
3589 case AUDIT_OBJ_USER:
3590 case AUDIT_OBJ_ROLE:
3591 case AUDIT_OBJ_TYPE:
3592 /* only 'equals' and 'not equals' fit user, role, and type */
3593 if (op != Audit_equal && op != Audit_not_equal)
3594 return -EINVAL;
3595 break;
3596 case AUDIT_SUBJ_SEN:
3597 case AUDIT_SUBJ_CLR:
3598 case AUDIT_OBJ_LEV_LOW:
3599 case AUDIT_OBJ_LEV_HIGH:
3600 /* we do not allow a range, indicated by the presence of '-' */
3601 if (strchr(rulestr, '-'))
3602 return -EINVAL;
3603 break;
3604 default:
3605 /* only the above fields are valid */
3606 return -EINVAL;
3607 }
3608
3609 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3610 if (!tmprule)
3611 return -ENOMEM;
3612
3613 context_init(&tmprule->au_ctxt);
3614
3615 rcu_read_lock();
3616 policy = rcu_dereference(state->policy);
3617 policydb = &policy->policydb;
3618
3619 tmprule->au_seqno = policy->latest_granting;
3620
3621 switch (field) {
3622 case AUDIT_SUBJ_USER:
3623 case AUDIT_OBJ_USER:
3624 rc = -EINVAL;
3625 userdatum = symtab_search(&policydb->p_users, rulestr);
3626 if (!userdatum)
3627 goto out;
3628 tmprule->au_ctxt.user = userdatum->value;
3629 break;
3630 case AUDIT_SUBJ_ROLE:
3631 case AUDIT_OBJ_ROLE:
3632 rc = -EINVAL;
3633 roledatum = symtab_search(&policydb->p_roles, rulestr);
3634 if (!roledatum)
3635 goto out;
3636 tmprule->au_ctxt.role = roledatum->value;
3637 break;
3638 case AUDIT_SUBJ_TYPE:
3639 case AUDIT_OBJ_TYPE:
3640 rc = -EINVAL;
3641 typedatum = symtab_search(&policydb->p_types, rulestr);
3642 if (!typedatum)
3643 goto out;
3644 tmprule->au_ctxt.type = typedatum->value;
3645 break;
3646 case AUDIT_SUBJ_SEN:
3647 case AUDIT_SUBJ_CLR:
3648 case AUDIT_OBJ_LEV_LOW:
3649 case AUDIT_OBJ_LEV_HIGH:
3650 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3651 GFP_ATOMIC);
3652 if (rc)
3653 goto out;
3654 break;
3655 }
3656 rc = 0;
3657out:
3658 rcu_read_unlock();
3659
3660 if (rc) {
3661 selinux_audit_rule_free(tmprule);
3662 tmprule = NULL;
3663 }
3664
3665 *rule = tmprule;
3666
3667 return rc;
3668}
3669
3670/* Check to see if the rule contains any selinux fields */
3671int selinux_audit_rule_known(struct audit_krule *rule)
3672{
3673 int i;
3674
3675 for (i = 0; i < rule->field_count; i++) {
3676 struct audit_field *f = &rule->fields[i];
3677 switch (f->type) {
3678 case AUDIT_SUBJ_USER:
3679 case AUDIT_SUBJ_ROLE:
3680 case AUDIT_SUBJ_TYPE:
3681 case AUDIT_SUBJ_SEN:
3682 case AUDIT_SUBJ_CLR:
3683 case AUDIT_OBJ_USER:
3684 case AUDIT_OBJ_ROLE:
3685 case AUDIT_OBJ_TYPE:
3686 case AUDIT_OBJ_LEV_LOW:
3687 case AUDIT_OBJ_LEV_HIGH:
3688 return 1;
3689 }
3690 }
3691
3692 return 0;
3693}
3694
3695int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule)
3696{
3697 struct selinux_state *state = &selinux_state;
3698 struct selinux_policy *policy;
3699 struct context *ctxt;
3700 struct mls_level *level;
3701 struct selinux_audit_rule *rule = vrule;
3702 int match = 0;
3703
3704 if (unlikely(!rule)) {
3705 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3706 return -ENOENT;
3707 }
3708
3709 if (!selinux_initialized(state))
3710 return 0;
3711
3712 rcu_read_lock();
3713
3714 policy = rcu_dereference(state->policy);
3715
3716 if (rule->au_seqno < policy->latest_granting) {
3717 match = -ESTALE;
3718 goto out;
3719 }
3720
3721 ctxt = sidtab_search(policy->sidtab, sid);
3722 if (unlikely(!ctxt)) {
3723 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3724 sid);
3725 match = -ENOENT;
3726 goto out;
3727 }
3728
3729 /* a field/op pair that is not caught here will simply fall through
3730 without a match */
3731 switch (field) {
3732 case AUDIT_SUBJ_USER:
3733 case AUDIT_OBJ_USER:
3734 switch (op) {
3735 case Audit_equal:
3736 match = (ctxt->user == rule->au_ctxt.user);
3737 break;
3738 case Audit_not_equal:
3739 match = (ctxt->user != rule->au_ctxt.user);
3740 break;
3741 }
3742 break;
3743 case AUDIT_SUBJ_ROLE:
3744 case AUDIT_OBJ_ROLE:
3745 switch (op) {
3746 case Audit_equal:
3747 match = (ctxt->role == rule->au_ctxt.role);
3748 break;
3749 case Audit_not_equal:
3750 match = (ctxt->role != rule->au_ctxt.role);
3751 break;
3752 }
3753 break;
3754 case AUDIT_SUBJ_TYPE:
3755 case AUDIT_OBJ_TYPE:
3756 switch (op) {
3757 case Audit_equal:
3758 match = (ctxt->type == rule->au_ctxt.type);
3759 break;
3760 case Audit_not_equal:
3761 match = (ctxt->type != rule->au_ctxt.type);
3762 break;
3763 }
3764 break;
3765 case AUDIT_SUBJ_SEN:
3766 case AUDIT_SUBJ_CLR:
3767 case AUDIT_OBJ_LEV_LOW:
3768 case AUDIT_OBJ_LEV_HIGH:
3769 level = ((field == AUDIT_SUBJ_SEN ||
3770 field == AUDIT_OBJ_LEV_LOW) ?
3771 &ctxt->range.level[0] : &ctxt->range.level[1]);
3772 switch (op) {
3773 case Audit_equal:
3774 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3775 level);
3776 break;
3777 case Audit_not_equal:
3778 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3779 level);
3780 break;
3781 case Audit_lt:
3782 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3783 level) &&
3784 !mls_level_eq(&rule->au_ctxt.range.level[0],
3785 level));
3786 break;
3787 case Audit_le:
3788 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3789 level);
3790 break;
3791 case Audit_gt:
3792 match = (mls_level_dom(level,
3793 &rule->au_ctxt.range.level[0]) &&
3794 !mls_level_eq(level,
3795 &rule->au_ctxt.range.level[0]));
3796 break;
3797 case Audit_ge:
3798 match = mls_level_dom(level,
3799 &rule->au_ctxt.range.level[0]);
3800 break;
3801 }
3802 }
3803
3804out:
3805 rcu_read_unlock();
3806 return match;
3807}
3808
3809static int aurule_avc_callback(u32 event)
3810{
3811 if (event == AVC_CALLBACK_RESET)
3812 return audit_update_lsm_rules();
3813 return 0;
3814}
3815
3816static int __init aurule_init(void)
3817{
3818 int err;
3819
3820 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3821 if (err)
3822 panic("avc_add_callback() failed, error %d\n", err);
3823
3824 return err;
3825}
3826__initcall(aurule_init);
3827
3828#ifdef CONFIG_NETLABEL
3829/**
3830 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3831 * @secattr: the NetLabel packet security attributes
3832 * @sid: the SELinux SID
3833 *
3834 * Description:
3835 * Attempt to cache the context in @ctx, which was derived from the packet in
3836 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3837 * already been initialized.
3838 *
3839 */
3840static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3841 u32 sid)
3842{
3843 u32 *sid_cache;
3844
3845 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3846 if (sid_cache == NULL)
3847 return;
3848 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3849 if (secattr->cache == NULL) {
3850 kfree(sid_cache);
3851 return;
3852 }
3853
3854 *sid_cache = sid;
3855 secattr->cache->free = kfree;
3856 secattr->cache->data = sid_cache;
3857 secattr->flags |= NETLBL_SECATTR_CACHE;
3858}
3859
3860/**
3861 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3862 * @state: SELinux state
3863 * @secattr: the NetLabel packet security attributes
3864 * @sid: the SELinux SID
3865 *
3866 * Description:
3867 * Convert the given NetLabel security attributes in @secattr into a
3868 * SELinux SID. If the @secattr field does not contain a full SELinux
3869 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3870 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3871 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3872 * conversion for future lookups. Returns zero on success, negative values on
3873 * failure.
3874 *
3875 */
3876int security_netlbl_secattr_to_sid(struct selinux_state *state,
3877 struct netlbl_lsm_secattr *secattr,
3878 u32 *sid)
3879{
3880 struct selinux_policy *policy;
3881 struct policydb *policydb;
3882 struct sidtab *sidtab;
3883 int rc;
3884 struct context *ctx;
3885 struct context ctx_new;
3886
3887 if (!selinux_initialized(state)) {
3888 *sid = SECSID_NULL;
3889 return 0;
3890 }
3891
3892retry:
3893 rc = 0;
3894 rcu_read_lock();
3895 policy = rcu_dereference(state->policy);
3896 policydb = &policy->policydb;
3897 sidtab = policy->sidtab;
3898
3899 if (secattr->flags & NETLBL_SECATTR_CACHE)
3900 *sid = *(u32 *)secattr->cache->data;
3901 else if (secattr->flags & NETLBL_SECATTR_SECID)
3902 *sid = secattr->attr.secid;
3903 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3904 rc = -EIDRM;
3905 ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3906 if (ctx == NULL)
3907 goto out;
3908
3909 context_init(&ctx_new);
3910 ctx_new.user = ctx->user;
3911 ctx_new.role = ctx->role;
3912 ctx_new.type = ctx->type;
3913 mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3914 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3915 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3916 if (rc)
3917 goto out;
3918 }
3919 rc = -EIDRM;
3920 if (!mls_context_isvalid(policydb, &ctx_new)) {
3921 ebitmap_destroy(&ctx_new.range.level[0].cat);
3922 goto out;
3923 }
3924
3925 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3926 ebitmap_destroy(&ctx_new.range.level[0].cat);
3927 if (rc == -ESTALE) {
3928 rcu_read_unlock();
3929 goto retry;
3930 }
3931 if (rc)
3932 goto out;
3933
3934 security_netlbl_cache_add(secattr, *sid);
3935 } else
3936 *sid = SECSID_NULL;
3937
3938out:
3939 rcu_read_unlock();
3940 return rc;
3941}
3942
3943/**
3944 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3945 * @state: SELinux state
3946 * @sid: the SELinux SID
3947 * @secattr: the NetLabel packet security attributes
3948 *
3949 * Description:
3950 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3951 * Returns zero on success, negative values on failure.
3952 *
3953 */
3954int security_netlbl_sid_to_secattr(struct selinux_state *state,
3955 u32 sid, struct netlbl_lsm_secattr *secattr)
3956{
3957 struct selinux_policy *policy;
3958 struct policydb *policydb;
3959 int rc;
3960 struct context *ctx;
3961
3962 if (!selinux_initialized(state))
3963 return 0;
3964
3965 rcu_read_lock();
3966 policy = rcu_dereference(state->policy);
3967 policydb = &policy->policydb;
3968
3969 rc = -ENOENT;
3970 ctx = sidtab_search(policy->sidtab, sid);
3971 if (ctx == NULL)
3972 goto out;
3973
3974 rc = -ENOMEM;
3975 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3976 GFP_ATOMIC);
3977 if (secattr->domain == NULL)
3978 goto out;
3979
3980 secattr->attr.secid = sid;
3981 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3982 mls_export_netlbl_lvl(policydb, ctx, secattr);
3983 rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3984out:
3985 rcu_read_unlock();
3986 return rc;
3987}
3988#endif /* CONFIG_NETLABEL */
3989
3990/**
3991 * __security_read_policy - read the policy.
3992 * @policy: SELinux policy
3993 * @data: binary policy data
3994 * @len: length of data in bytes
3995 *
3996 */
3997static int __security_read_policy(struct selinux_policy *policy,
3998 void *data, size_t *len)
3999{
4000 int rc;
4001 struct policy_file fp;
4002
4003 fp.data = data;
4004 fp.len = *len;
4005
4006 rc = policydb_write(&policy->policydb, &fp);
4007 if (rc)
4008 return rc;
4009
4010 *len = (unsigned long)fp.data - (unsigned long)data;
4011 return 0;
4012}
4013
4014/**
4015 * security_read_policy - read the policy.
4016 * @state: selinux_state
4017 * @data: binary policy data
4018 * @len: length of data in bytes
4019 *
4020 */
4021int security_read_policy(struct selinux_state *state,
4022 void **data, size_t *len)
4023{
4024 struct selinux_policy *policy;
4025
4026 policy = rcu_dereference_protected(
4027 state->policy, lockdep_is_held(&state->policy_mutex));
4028 if (!policy)
4029 return -EINVAL;
4030
4031 *len = policy->policydb.len;
4032 *data = vmalloc_user(*len);
4033 if (!*data)
4034 return -ENOMEM;
4035
4036 return __security_read_policy(policy, *data, len);
4037}
4038
4039/**
4040 * security_read_state_kernel - read the policy.
4041 * @state: selinux_state
4042 * @data: binary policy data
4043 * @len: length of data in bytes
4044 *
4045 * Allocates kernel memory for reading SELinux policy.
4046 * This function is for internal use only and should not
4047 * be used for returning data to user space.
4048 *
4049 * This function must be called with policy_mutex held.
4050 */
4051int security_read_state_kernel(struct selinux_state *state,
4052 void **data, size_t *len)
4053{
4054 struct selinux_policy *policy;
4055
4056 policy = rcu_dereference_protected(
4057 state->policy, lockdep_is_held(&state->policy_mutex));
4058 if (!policy)
4059 return -EINVAL;
4060
4061 *len = policy->policydb.len;
4062 *data = vmalloc(*len);
4063 if (!*data)
4064 return -ENOMEM;
4065
4066 return __security_read_policy(policy, *data, len);
4067}