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