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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Implementation of the security services.
4 *
5 * Authors : Stephen Smalley, <sds@tycho.nsa.gov>
6 * James Morris <jmorris@redhat.com>
7 *
8 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
9 *
10 * Support for enhanced MLS infrastructure.
11 * Support for context based audit filters.
12 *
13 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
14 *
15 * Added conditional policy language extensions
16 *
17 * Updated: Hewlett-Packard <paul@paul-moore.com>
18 *
19 * Added support for NetLabel
20 * Added support for the policy capability bitmap
21 *
22 * Updated: Chad Sellers <csellers@tresys.com>
23 *
24 * Added validation of kernel classes and permissions
25 *
26 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
27 *
28 * Added support for bounds domain and audit messaged on masked permissions
29 *
30 * Updated: Guido Trentalancia <guido@trentalancia.com>
31 *
32 * Added support for runtime switching of the policy type
33 *
34 * Copyright (C) 2008, 2009 NEC Corporation
35 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
36 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
37 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
38 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
39 */
40#include <linux/kernel.h>
41#include <linux/slab.h>
42#include <linux/string.h>
43#include <linux/spinlock.h>
44#include <linux/rcupdate.h>
45#include <linux/errno.h>
46#include <linux/in.h>
47#include <linux/sched.h>
48#include <linux/audit.h>
49#include <linux/vmalloc.h>
50#include <linux/lsm_hooks.h>
51#include <net/netlabel.h>
52
53#include "flask.h"
54#include "avc.h"
55#include "avc_ss.h"
56#include "security.h"
57#include "context.h"
58#include "policydb.h"
59#include "sidtab.h"
60#include "services.h"
61#include "conditional.h"
62#include "mls.h"
63#include "objsec.h"
64#include "netlabel.h"
65#include "xfrm.h"
66#include "ebitmap.h"
67#include "audit.h"
68#include "policycap_names.h"
69#include "ima.h"
70
71struct convert_context_args {
72 struct selinux_state *state;
73 struct policydb *oldp;
74 struct policydb *newp;
75};
76
77struct selinux_policy_convert_data {
78 struct convert_context_args args;
79 struct sidtab_convert_params sidtab_params;
80};
81
82/* Forward declaration. */
83static int context_struct_to_string(struct policydb *policydb,
84 struct context *context,
85 char **scontext,
86 u32 *scontext_len);
87
88static int sidtab_entry_to_string(struct policydb *policydb,
89 struct sidtab *sidtab,
90 struct sidtab_entry *entry,
91 char **scontext,
92 u32 *scontext_len);
93
94static void context_struct_compute_av(struct policydb *policydb,
95 struct context *scontext,
96 struct context *tcontext,
97 u16 tclass,
98 struct av_decision *avd,
99 struct extended_perms *xperms);
100
101static int selinux_set_mapping(struct policydb *pol,
102 struct security_class_mapping *map,
103 struct selinux_map *out_map)
104{
105 u16 i, j;
106 unsigned k;
107 bool print_unknown_handle = false;
108
109 /* Find number of classes in the input mapping */
110 if (!map)
111 return -EINVAL;
112 i = 0;
113 while (map[i].name)
114 i++;
115
116 /* Allocate space for the class records, plus one for class zero */
117 out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC);
118 if (!out_map->mapping)
119 return -ENOMEM;
120
121 /* Store the raw class and permission values */
122 j = 0;
123 while (map[j].name) {
124 struct security_class_mapping *p_in = map + (j++);
125 struct selinux_mapping *p_out = out_map->mapping + j;
126
127 /* An empty class string skips ahead */
128 if (!strcmp(p_in->name, "")) {
129 p_out->num_perms = 0;
130 continue;
131 }
132
133 p_out->value = string_to_security_class(pol, p_in->name);
134 if (!p_out->value) {
135 pr_info("SELinux: Class %s not defined in policy.\n",
136 p_in->name);
137 if (pol->reject_unknown)
138 goto err;
139 p_out->num_perms = 0;
140 print_unknown_handle = true;
141 continue;
142 }
143
144 k = 0;
145 while (p_in->perms[k]) {
146 /* An empty permission string skips ahead */
147 if (!*p_in->perms[k]) {
148 k++;
149 continue;
150 }
151 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
152 p_in->perms[k]);
153 if (!p_out->perms[k]) {
154 pr_info("SELinux: Permission %s in class %s not defined in policy.\n",
155 p_in->perms[k], p_in->name);
156 if (pol->reject_unknown)
157 goto err;
158 print_unknown_handle = true;
159 }
160
161 k++;
162 }
163 p_out->num_perms = k;
164 }
165
166 if (print_unknown_handle)
167 pr_info("SELinux: the above unknown classes and permissions will be %s\n",
168 pol->allow_unknown ? "allowed" : "denied");
169
170 out_map->size = i;
171 return 0;
172err:
173 kfree(out_map->mapping);
174 out_map->mapping = NULL;
175 return -EINVAL;
176}
177
178/*
179 * Get real, policy values from mapped values
180 */
181
182static u16 unmap_class(struct selinux_map *map, u16 tclass)
183{
184 if (tclass < map->size)
185 return map->mapping[tclass].value;
186
187 return tclass;
188}
189
190/*
191 * Get kernel value for class from its policy value
192 */
193static u16 map_class(struct selinux_map *map, u16 pol_value)
194{
195 u16 i;
196
197 for (i = 1; i < map->size; i++) {
198 if (map->mapping[i].value == pol_value)
199 return i;
200 }
201
202 return SECCLASS_NULL;
203}
204
205static void map_decision(struct selinux_map *map,
206 u16 tclass, struct av_decision *avd,
207 int allow_unknown)
208{
209 if (tclass < map->size) {
210 struct selinux_mapping *mapping = &map->mapping[tclass];
211 unsigned int i, n = mapping->num_perms;
212 u32 result;
213
214 for (i = 0, result = 0; i < n; i++) {
215 if (avd->allowed & mapping->perms[i])
216 result |= 1<<i;
217 if (allow_unknown && !mapping->perms[i])
218 result |= 1<<i;
219 }
220 avd->allowed = result;
221
222 for (i = 0, result = 0; i < n; i++)
223 if (avd->auditallow & mapping->perms[i])
224 result |= 1<<i;
225 avd->auditallow = result;
226
227 for (i = 0, result = 0; i < n; i++) {
228 if (avd->auditdeny & mapping->perms[i])
229 result |= 1<<i;
230 if (!allow_unknown && !mapping->perms[i])
231 result |= 1<<i;
232 }
233 /*
234 * In case the kernel has a bug and requests a permission
235 * between num_perms and the maximum permission number, we
236 * should audit that denial
237 */
238 for (; i < (sizeof(u32)*8); i++)
239 result |= 1<<i;
240 avd->auditdeny = result;
241 }
242}
243
244int security_mls_enabled(struct selinux_state *state)
245{
246 int mls_enabled;
247 struct selinux_policy *policy;
248
249 if (!selinux_initialized(state))
250 return 0;
251
252 rcu_read_lock();
253 policy = rcu_dereference(state->policy);
254 mls_enabled = policy->policydb.mls_enabled;
255 rcu_read_unlock();
256 return mls_enabled;
257}
258
259/*
260 * Return the boolean value of a constraint expression
261 * when it is applied to the specified source and target
262 * security contexts.
263 *
264 * xcontext is a special beast... It is used by the validatetrans rules
265 * only. For these rules, scontext is the context before the transition,
266 * tcontext is the context after the transition, and xcontext is the context
267 * of the process performing the transition. All other callers of
268 * constraint_expr_eval should pass in NULL for xcontext.
269 */
270static int constraint_expr_eval(struct policydb *policydb,
271 struct context *scontext,
272 struct context *tcontext,
273 struct context *xcontext,
274 struct constraint_expr *cexpr)
275{
276 u32 val1, val2;
277 struct context *c;
278 struct role_datum *r1, *r2;
279 struct mls_level *l1, *l2;
280 struct constraint_expr *e;
281 int s[CEXPR_MAXDEPTH];
282 int sp = -1;
283
284 for (e = cexpr; e; e = e->next) {
285 switch (e->expr_type) {
286 case CEXPR_NOT:
287 BUG_ON(sp < 0);
288 s[sp] = !s[sp];
289 break;
290 case CEXPR_AND:
291 BUG_ON(sp < 1);
292 sp--;
293 s[sp] &= s[sp + 1];
294 break;
295 case CEXPR_OR:
296 BUG_ON(sp < 1);
297 sp--;
298 s[sp] |= s[sp + 1];
299 break;
300 case CEXPR_ATTR:
301 if (sp == (CEXPR_MAXDEPTH - 1))
302 return 0;
303 switch (e->attr) {
304 case CEXPR_USER:
305 val1 = scontext->user;
306 val2 = tcontext->user;
307 break;
308 case CEXPR_TYPE:
309 val1 = scontext->type;
310 val2 = tcontext->type;
311 break;
312 case CEXPR_ROLE:
313 val1 = scontext->role;
314 val2 = tcontext->role;
315 r1 = policydb->role_val_to_struct[val1 - 1];
316 r2 = policydb->role_val_to_struct[val2 - 1];
317 switch (e->op) {
318 case CEXPR_DOM:
319 s[++sp] = ebitmap_get_bit(&r1->dominates,
320 val2 - 1);
321 continue;
322 case CEXPR_DOMBY:
323 s[++sp] = ebitmap_get_bit(&r2->dominates,
324 val1 - 1);
325 continue;
326 case CEXPR_INCOMP:
327 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
328 val2 - 1) &&
329 !ebitmap_get_bit(&r2->dominates,
330 val1 - 1));
331 continue;
332 default:
333 break;
334 }
335 break;
336 case CEXPR_L1L2:
337 l1 = &(scontext->range.level[0]);
338 l2 = &(tcontext->range.level[0]);
339 goto mls_ops;
340 case CEXPR_L1H2:
341 l1 = &(scontext->range.level[0]);
342 l2 = &(tcontext->range.level[1]);
343 goto mls_ops;
344 case CEXPR_H1L2:
345 l1 = &(scontext->range.level[1]);
346 l2 = &(tcontext->range.level[0]);
347 goto mls_ops;
348 case CEXPR_H1H2:
349 l1 = &(scontext->range.level[1]);
350 l2 = &(tcontext->range.level[1]);
351 goto mls_ops;
352 case CEXPR_L1H1:
353 l1 = &(scontext->range.level[0]);
354 l2 = &(scontext->range.level[1]);
355 goto mls_ops;
356 case CEXPR_L2H2:
357 l1 = &(tcontext->range.level[0]);
358 l2 = &(tcontext->range.level[1]);
359 goto mls_ops;
360mls_ops:
361 switch (e->op) {
362 case CEXPR_EQ:
363 s[++sp] = mls_level_eq(l1, l2);
364 continue;
365 case CEXPR_NEQ:
366 s[++sp] = !mls_level_eq(l1, l2);
367 continue;
368 case CEXPR_DOM:
369 s[++sp] = mls_level_dom(l1, l2);
370 continue;
371 case CEXPR_DOMBY:
372 s[++sp] = mls_level_dom(l2, l1);
373 continue;
374 case CEXPR_INCOMP:
375 s[++sp] = mls_level_incomp(l2, l1);
376 continue;
377 default:
378 BUG();
379 return 0;
380 }
381 break;
382 default:
383 BUG();
384 return 0;
385 }
386
387 switch (e->op) {
388 case CEXPR_EQ:
389 s[++sp] = (val1 == val2);
390 break;
391 case CEXPR_NEQ:
392 s[++sp] = (val1 != val2);
393 break;
394 default:
395 BUG();
396 return 0;
397 }
398 break;
399 case CEXPR_NAMES:
400 if (sp == (CEXPR_MAXDEPTH-1))
401 return 0;
402 c = scontext;
403 if (e->attr & CEXPR_TARGET)
404 c = tcontext;
405 else if (e->attr & CEXPR_XTARGET) {
406 c = xcontext;
407 if (!c) {
408 BUG();
409 return 0;
410 }
411 }
412 if (e->attr & CEXPR_USER)
413 val1 = c->user;
414 else if (e->attr & CEXPR_ROLE)
415 val1 = c->role;
416 else if (e->attr & CEXPR_TYPE)
417 val1 = c->type;
418 else {
419 BUG();
420 return 0;
421 }
422
423 switch (e->op) {
424 case CEXPR_EQ:
425 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
426 break;
427 case CEXPR_NEQ:
428 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
429 break;
430 default:
431 BUG();
432 return 0;
433 }
434 break;
435 default:
436 BUG();
437 return 0;
438 }
439 }
440
441 BUG_ON(sp != 0);
442 return s[0];
443}
444
445/*
446 * security_dump_masked_av - dumps masked permissions during
447 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
448 */
449static int dump_masked_av_helper(void *k, void *d, void *args)
450{
451 struct perm_datum *pdatum = d;
452 char **permission_names = args;
453
454 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
455
456 permission_names[pdatum->value - 1] = (char *)k;
457
458 return 0;
459}
460
461static void security_dump_masked_av(struct policydb *policydb,
462 struct context *scontext,
463 struct context *tcontext,
464 u16 tclass,
465 u32 permissions,
466 const char *reason)
467{
468 struct common_datum *common_dat;
469 struct class_datum *tclass_dat;
470 struct audit_buffer *ab;
471 char *tclass_name;
472 char *scontext_name = NULL;
473 char *tcontext_name = NULL;
474 char *permission_names[32];
475 int index;
476 u32 length;
477 bool need_comma = false;
478
479 if (!permissions)
480 return;
481
482 tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1);
483 tclass_dat = policydb->class_val_to_struct[tclass - 1];
484 common_dat = tclass_dat->comdatum;
485
486 /* init permission_names */
487 if (common_dat &&
488 hashtab_map(&common_dat->permissions.table,
489 dump_masked_av_helper, permission_names) < 0)
490 goto out;
491
492 if (hashtab_map(&tclass_dat->permissions.table,
493 dump_masked_av_helper, permission_names) < 0)
494 goto out;
495
496 /* get scontext/tcontext in text form */
497 if (context_struct_to_string(policydb, scontext,
498 &scontext_name, &length) < 0)
499 goto out;
500
501 if (context_struct_to_string(policydb, tcontext,
502 &tcontext_name, &length) < 0)
503 goto out;
504
505 /* audit a message */
506 ab = audit_log_start(audit_context(),
507 GFP_ATOMIC, AUDIT_SELINUX_ERR);
508 if (!ab)
509 goto out;
510
511 audit_log_format(ab, "op=security_compute_av reason=%s "
512 "scontext=%s tcontext=%s tclass=%s perms=",
513 reason, scontext_name, tcontext_name, tclass_name);
514
515 for (index = 0; index < 32; index++) {
516 u32 mask = (1 << index);
517
518 if ((mask & permissions) == 0)
519 continue;
520
521 audit_log_format(ab, "%s%s",
522 need_comma ? "," : "",
523 permission_names[index]
524 ? permission_names[index] : "????");
525 need_comma = true;
526 }
527 audit_log_end(ab);
528out:
529 /* release scontext/tcontext */
530 kfree(tcontext_name);
531 kfree(scontext_name);
532
533 return;
534}
535
536/*
537 * security_boundary_permission - drops violated permissions
538 * on boundary constraint.
539 */
540static void type_attribute_bounds_av(struct policydb *policydb,
541 struct context *scontext,
542 struct context *tcontext,
543 u16 tclass,
544 struct av_decision *avd)
545{
546 struct context lo_scontext;
547 struct context lo_tcontext, *tcontextp = tcontext;
548 struct av_decision lo_avd;
549 struct type_datum *source;
550 struct type_datum *target;
551 u32 masked = 0;
552
553 source = policydb->type_val_to_struct[scontext->type - 1];
554 BUG_ON(!source);
555
556 if (!source->bounds)
557 return;
558
559 target = policydb->type_val_to_struct[tcontext->type - 1];
560 BUG_ON(!target);
561
562 memset(&lo_avd, 0, sizeof(lo_avd));
563
564 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
565 lo_scontext.type = source->bounds;
566
567 if (target->bounds) {
568 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
569 lo_tcontext.type = target->bounds;
570 tcontextp = &lo_tcontext;
571 }
572
573 context_struct_compute_av(policydb, &lo_scontext,
574 tcontextp,
575 tclass,
576 &lo_avd,
577 NULL);
578
579 masked = ~lo_avd.allowed & avd->allowed;
580
581 if (likely(!masked))
582 return; /* no masked permission */
583
584 /* mask violated permissions */
585 avd->allowed &= ~masked;
586
587 /* audit masked permissions */
588 security_dump_masked_av(policydb, scontext, tcontext,
589 tclass, masked, "bounds");
590}
591
592/*
593 * flag which drivers have permissions
594 * only looking for ioctl based extended permssions
595 */
596void services_compute_xperms_drivers(
597 struct extended_perms *xperms,
598 struct avtab_node *node)
599{
600 unsigned int i;
601
602 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
603 /* if one or more driver has all permissions allowed */
604 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
605 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
606 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
607 /* if allowing permissions within a driver */
608 security_xperm_set(xperms->drivers.p,
609 node->datum.u.xperms->driver);
610 }
611
612 xperms->len = 1;
613}
614
615/*
616 * Compute access vectors and extended permissions based on a context
617 * structure pair for the permissions in a particular class.
618 */
619static void context_struct_compute_av(struct policydb *policydb,
620 struct context *scontext,
621 struct context *tcontext,
622 u16 tclass,
623 struct av_decision *avd,
624 struct extended_perms *xperms)
625{
626 struct constraint_node *constraint;
627 struct role_allow *ra;
628 struct avtab_key avkey;
629 struct avtab_node *node;
630 struct class_datum *tclass_datum;
631 struct ebitmap *sattr, *tattr;
632 struct ebitmap_node *snode, *tnode;
633 unsigned int i, j;
634
635 avd->allowed = 0;
636 avd->auditallow = 0;
637 avd->auditdeny = 0xffffffff;
638 if (xperms) {
639 memset(&xperms->drivers, 0, sizeof(xperms->drivers));
640 xperms->len = 0;
641 }
642
643 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
644 if (printk_ratelimit())
645 pr_warn("SELinux: Invalid class %hu\n", tclass);
646 return;
647 }
648
649 tclass_datum = policydb->class_val_to_struct[tclass - 1];
650
651 /*
652 * If a specific type enforcement rule was defined for
653 * this permission check, then use it.
654 */
655 avkey.target_class = tclass;
656 avkey.specified = AVTAB_AV | AVTAB_XPERMS;
657 sattr = &policydb->type_attr_map_array[scontext->type - 1];
658 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
659 ebitmap_for_each_positive_bit(sattr, snode, i) {
660 ebitmap_for_each_positive_bit(tattr, tnode, j) {
661 avkey.source_type = i + 1;
662 avkey.target_type = j + 1;
663 for (node = avtab_search_node(&policydb->te_avtab,
664 &avkey);
665 node;
666 node = avtab_search_node_next(node, avkey.specified)) {
667 if (node->key.specified == AVTAB_ALLOWED)
668 avd->allowed |= node->datum.u.data;
669 else if (node->key.specified == AVTAB_AUDITALLOW)
670 avd->auditallow |= node->datum.u.data;
671 else if (node->key.specified == AVTAB_AUDITDENY)
672 avd->auditdeny &= node->datum.u.data;
673 else if (xperms && (node->key.specified & AVTAB_XPERMS))
674 services_compute_xperms_drivers(xperms, node);
675 }
676
677 /* Check conditional av table for additional permissions */
678 cond_compute_av(&policydb->te_cond_avtab, &avkey,
679 avd, xperms);
680
681 }
682 }
683
684 /*
685 * Remove any permissions prohibited by a constraint (this includes
686 * the MLS policy).
687 */
688 constraint = tclass_datum->constraints;
689 while (constraint) {
690 if ((constraint->permissions & (avd->allowed)) &&
691 !constraint_expr_eval(policydb, scontext, tcontext, NULL,
692 constraint->expr)) {
693 avd->allowed &= ~(constraint->permissions);
694 }
695 constraint = constraint->next;
696 }
697
698 /*
699 * If checking process transition permission and the
700 * role is changing, then check the (current_role, new_role)
701 * pair.
702 */
703 if (tclass == policydb->process_class &&
704 (avd->allowed & policydb->process_trans_perms) &&
705 scontext->role != tcontext->role) {
706 for (ra = policydb->role_allow; ra; ra = ra->next) {
707 if (scontext->role == ra->role &&
708 tcontext->role == ra->new_role)
709 break;
710 }
711 if (!ra)
712 avd->allowed &= ~policydb->process_trans_perms;
713 }
714
715 /*
716 * If the given source and target types have boundary
717 * constraint, lazy checks have to mask any violated
718 * permission and notice it to userspace via audit.
719 */
720 type_attribute_bounds_av(policydb, scontext, tcontext,
721 tclass, avd);
722}
723
724static int security_validtrans_handle_fail(struct selinux_state *state,
725 struct selinux_policy *policy,
726 struct sidtab_entry *oentry,
727 struct sidtab_entry *nentry,
728 struct sidtab_entry *tentry,
729 u16 tclass)
730{
731 struct policydb *p = &policy->policydb;
732 struct sidtab *sidtab = policy->sidtab;
733 char *o = NULL, *n = NULL, *t = NULL;
734 u32 olen, nlen, tlen;
735
736 if (sidtab_entry_to_string(p, sidtab, oentry, &o, &olen))
737 goto out;
738 if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen))
739 goto out;
740 if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen))
741 goto out;
742 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR,
743 "op=security_validate_transition seresult=denied"
744 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
745 o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
746out:
747 kfree(o);
748 kfree(n);
749 kfree(t);
750
751 if (!enforcing_enabled(state))
752 return 0;
753 return -EPERM;
754}
755
756static int security_compute_validatetrans(struct selinux_state *state,
757 u32 oldsid, u32 newsid, u32 tasksid,
758 u16 orig_tclass, bool user)
759{
760 struct selinux_policy *policy;
761 struct policydb *policydb;
762 struct sidtab *sidtab;
763 struct sidtab_entry *oentry;
764 struct sidtab_entry *nentry;
765 struct sidtab_entry *tentry;
766 struct class_datum *tclass_datum;
767 struct constraint_node *constraint;
768 u16 tclass;
769 int rc = 0;
770
771
772 if (!selinux_initialized(state))
773 return 0;
774
775 rcu_read_lock();
776
777 policy = rcu_dereference(state->policy);
778 policydb = &policy->policydb;
779 sidtab = policy->sidtab;
780
781 if (!user)
782 tclass = unmap_class(&policy->map, orig_tclass);
783 else
784 tclass = orig_tclass;
785
786 if (!tclass || tclass > policydb->p_classes.nprim) {
787 rc = -EINVAL;
788 goto out;
789 }
790 tclass_datum = policydb->class_val_to_struct[tclass - 1];
791
792 oentry = sidtab_search_entry(sidtab, oldsid);
793 if (!oentry) {
794 pr_err("SELinux: %s: unrecognized SID %d\n",
795 __func__, oldsid);
796 rc = -EINVAL;
797 goto out;
798 }
799
800 nentry = sidtab_search_entry(sidtab, newsid);
801 if (!nentry) {
802 pr_err("SELinux: %s: unrecognized SID %d\n",
803 __func__, newsid);
804 rc = -EINVAL;
805 goto out;
806 }
807
808 tentry = sidtab_search_entry(sidtab, tasksid);
809 if (!tentry) {
810 pr_err("SELinux: %s: unrecognized SID %d\n",
811 __func__, tasksid);
812 rc = -EINVAL;
813 goto out;
814 }
815
816 constraint = tclass_datum->validatetrans;
817 while (constraint) {
818 if (!constraint_expr_eval(policydb, &oentry->context,
819 &nentry->context, &tentry->context,
820 constraint->expr)) {
821 if (user)
822 rc = -EPERM;
823 else
824 rc = security_validtrans_handle_fail(state,
825 policy,
826 oentry,
827 nentry,
828 tentry,
829 tclass);
830 goto out;
831 }
832 constraint = constraint->next;
833 }
834
835out:
836 rcu_read_unlock();
837 return rc;
838}
839
840int security_validate_transition_user(struct selinux_state *state,
841 u32 oldsid, u32 newsid, u32 tasksid,
842 u16 tclass)
843{
844 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
845 tclass, true);
846}
847
848int security_validate_transition(struct selinux_state *state,
849 u32 oldsid, u32 newsid, u32 tasksid,
850 u16 orig_tclass)
851{
852 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
853 orig_tclass, false);
854}
855
856/*
857 * security_bounded_transition - check whether the given
858 * transition is directed to bounded, or not.
859 * It returns 0, if @newsid is bounded by @oldsid.
860 * Otherwise, it returns error code.
861 *
862 * @state: SELinux state
863 * @oldsid : current security identifier
864 * @newsid : destinated security identifier
865 */
866int security_bounded_transition(struct selinux_state *state,
867 u32 old_sid, u32 new_sid)
868{
869 struct selinux_policy *policy;
870 struct policydb *policydb;
871 struct sidtab *sidtab;
872 struct sidtab_entry *old_entry, *new_entry;
873 struct type_datum *type;
874 int index;
875 int rc;
876
877 if (!selinux_initialized(state))
878 return 0;
879
880 rcu_read_lock();
881 policy = rcu_dereference(state->policy);
882 policydb = &policy->policydb;
883 sidtab = policy->sidtab;
884
885 rc = -EINVAL;
886 old_entry = sidtab_search_entry(sidtab, old_sid);
887 if (!old_entry) {
888 pr_err("SELinux: %s: unrecognized SID %u\n",
889 __func__, old_sid);
890 goto out;
891 }
892
893 rc = -EINVAL;
894 new_entry = sidtab_search_entry(sidtab, new_sid);
895 if (!new_entry) {
896 pr_err("SELinux: %s: unrecognized SID %u\n",
897 __func__, new_sid);
898 goto out;
899 }
900
901 rc = 0;
902 /* type/domain unchanged */
903 if (old_entry->context.type == new_entry->context.type)
904 goto out;
905
906 index = new_entry->context.type;
907 while (true) {
908 type = policydb->type_val_to_struct[index - 1];
909 BUG_ON(!type);
910
911 /* not bounded anymore */
912 rc = -EPERM;
913 if (!type->bounds)
914 break;
915
916 /* @newsid is bounded by @oldsid */
917 rc = 0;
918 if (type->bounds == old_entry->context.type)
919 break;
920
921 index = type->bounds;
922 }
923
924 if (rc) {
925 char *old_name = NULL;
926 char *new_name = NULL;
927 u32 length;
928
929 if (!sidtab_entry_to_string(policydb, sidtab, old_entry,
930 &old_name, &length) &&
931 !sidtab_entry_to_string(policydb, sidtab, new_entry,
932 &new_name, &length)) {
933 audit_log(audit_context(),
934 GFP_ATOMIC, AUDIT_SELINUX_ERR,
935 "op=security_bounded_transition "
936 "seresult=denied "
937 "oldcontext=%s newcontext=%s",
938 old_name, new_name);
939 }
940 kfree(new_name);
941 kfree(old_name);
942 }
943out:
944 rcu_read_unlock();
945
946 return rc;
947}
948
949static void avd_init(struct selinux_policy *policy, struct av_decision *avd)
950{
951 avd->allowed = 0;
952 avd->auditallow = 0;
953 avd->auditdeny = 0xffffffff;
954 if (policy)
955 avd->seqno = policy->latest_granting;
956 else
957 avd->seqno = 0;
958 avd->flags = 0;
959}
960
961void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
962 struct avtab_node *node)
963{
964 unsigned int i;
965
966 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
967 if (xpermd->driver != node->datum.u.xperms->driver)
968 return;
969 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
970 if (!security_xperm_test(node->datum.u.xperms->perms.p,
971 xpermd->driver))
972 return;
973 } else {
974 BUG();
975 }
976
977 if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
978 xpermd->used |= XPERMS_ALLOWED;
979 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
980 memset(xpermd->allowed->p, 0xff,
981 sizeof(xpermd->allowed->p));
982 }
983 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
984 for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++)
985 xpermd->allowed->p[i] |=
986 node->datum.u.xperms->perms.p[i];
987 }
988 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
989 xpermd->used |= XPERMS_AUDITALLOW;
990 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
991 memset(xpermd->auditallow->p, 0xff,
992 sizeof(xpermd->auditallow->p));
993 }
994 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
995 for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++)
996 xpermd->auditallow->p[i] |=
997 node->datum.u.xperms->perms.p[i];
998 }
999 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
1000 xpermd->used |= XPERMS_DONTAUDIT;
1001 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
1002 memset(xpermd->dontaudit->p, 0xff,
1003 sizeof(xpermd->dontaudit->p));
1004 }
1005 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
1006 for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++)
1007 xpermd->dontaudit->p[i] |=
1008 node->datum.u.xperms->perms.p[i];
1009 }
1010 } else {
1011 BUG();
1012 }
1013}
1014
1015void security_compute_xperms_decision(struct selinux_state *state,
1016 u32 ssid,
1017 u32 tsid,
1018 u16 orig_tclass,
1019 u8 driver,
1020 struct extended_perms_decision *xpermd)
1021{
1022 struct selinux_policy *policy;
1023 struct policydb *policydb;
1024 struct sidtab *sidtab;
1025 u16 tclass;
1026 struct context *scontext, *tcontext;
1027 struct avtab_key avkey;
1028 struct avtab_node *node;
1029 struct ebitmap *sattr, *tattr;
1030 struct ebitmap_node *snode, *tnode;
1031 unsigned int i, j;
1032
1033 xpermd->driver = driver;
1034 xpermd->used = 0;
1035 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1036 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1037 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1038
1039 rcu_read_lock();
1040 if (!selinux_initialized(state))
1041 goto allow;
1042
1043 policy = rcu_dereference(state->policy);
1044 policydb = &policy->policydb;
1045 sidtab = policy->sidtab;
1046
1047 scontext = sidtab_search(sidtab, ssid);
1048 if (!scontext) {
1049 pr_err("SELinux: %s: unrecognized SID %d\n",
1050 __func__, ssid);
1051 goto out;
1052 }
1053
1054 tcontext = sidtab_search(sidtab, tsid);
1055 if (!tcontext) {
1056 pr_err("SELinux: %s: unrecognized SID %d\n",
1057 __func__, tsid);
1058 goto out;
1059 }
1060
1061 tclass = unmap_class(&policy->map, orig_tclass);
1062 if (unlikely(orig_tclass && !tclass)) {
1063 if (policydb->allow_unknown)
1064 goto allow;
1065 goto out;
1066 }
1067
1068
1069 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1070 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1071 goto out;
1072 }
1073
1074 avkey.target_class = tclass;
1075 avkey.specified = AVTAB_XPERMS;
1076 sattr = &policydb->type_attr_map_array[scontext->type - 1];
1077 tattr = &policydb->type_attr_map_array[tcontext->type - 1];
1078 ebitmap_for_each_positive_bit(sattr, snode, i) {
1079 ebitmap_for_each_positive_bit(tattr, tnode, j) {
1080 avkey.source_type = i + 1;
1081 avkey.target_type = j + 1;
1082 for (node = avtab_search_node(&policydb->te_avtab,
1083 &avkey);
1084 node;
1085 node = avtab_search_node_next(node, avkey.specified))
1086 services_compute_xperms_decision(xpermd, node);
1087
1088 cond_compute_xperms(&policydb->te_cond_avtab,
1089 &avkey, xpermd);
1090 }
1091 }
1092out:
1093 rcu_read_unlock();
1094 return;
1095allow:
1096 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1097 goto out;
1098}
1099
1100/**
1101 * security_compute_av - Compute access vector decisions.
1102 * @state: SELinux state
1103 * @ssid: source security identifier
1104 * @tsid: target security identifier
1105 * @tclass: target security class
1106 * @avd: access vector decisions
1107 * @xperms: extended permissions
1108 *
1109 * Compute a set of access vector decisions based on the
1110 * SID pair (@ssid, @tsid) for the permissions in @tclass.
1111 */
1112void security_compute_av(struct selinux_state *state,
1113 u32 ssid,
1114 u32 tsid,
1115 u16 orig_tclass,
1116 struct av_decision *avd,
1117 struct extended_perms *xperms)
1118{
1119 struct selinux_policy *policy;
1120 struct policydb *policydb;
1121 struct sidtab *sidtab;
1122 u16 tclass;
1123 struct context *scontext = NULL, *tcontext = NULL;
1124
1125 rcu_read_lock();
1126 policy = rcu_dereference(state->policy);
1127 avd_init(policy, avd);
1128 xperms->len = 0;
1129 if (!selinux_initialized(state))
1130 goto allow;
1131
1132 policydb = &policy->policydb;
1133 sidtab = policy->sidtab;
1134
1135 scontext = sidtab_search(sidtab, ssid);
1136 if (!scontext) {
1137 pr_err("SELinux: %s: unrecognized SID %d\n",
1138 __func__, ssid);
1139 goto out;
1140 }
1141
1142 /* permissive domain? */
1143 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1144 avd->flags |= AVD_FLAGS_PERMISSIVE;
1145
1146 tcontext = sidtab_search(sidtab, tsid);
1147 if (!tcontext) {
1148 pr_err("SELinux: %s: unrecognized SID %d\n",
1149 __func__, tsid);
1150 goto out;
1151 }
1152
1153 tclass = unmap_class(&policy->map, orig_tclass);
1154 if (unlikely(orig_tclass && !tclass)) {
1155 if (policydb->allow_unknown)
1156 goto allow;
1157 goto out;
1158 }
1159 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1160 xperms);
1161 map_decision(&policy->map, orig_tclass, avd,
1162 policydb->allow_unknown);
1163out:
1164 rcu_read_unlock();
1165 return;
1166allow:
1167 avd->allowed = 0xffffffff;
1168 goto out;
1169}
1170
1171void security_compute_av_user(struct selinux_state *state,
1172 u32 ssid,
1173 u32 tsid,
1174 u16 tclass,
1175 struct av_decision *avd)
1176{
1177 struct selinux_policy *policy;
1178 struct policydb *policydb;
1179 struct sidtab *sidtab;
1180 struct context *scontext = NULL, *tcontext = NULL;
1181
1182 rcu_read_lock();
1183 policy = rcu_dereference(state->policy);
1184 avd_init(policy, avd);
1185 if (!selinux_initialized(state))
1186 goto allow;
1187
1188 policydb = &policy->policydb;
1189 sidtab = policy->sidtab;
1190
1191 scontext = sidtab_search(sidtab, ssid);
1192 if (!scontext) {
1193 pr_err("SELinux: %s: unrecognized SID %d\n",
1194 __func__, ssid);
1195 goto out;
1196 }
1197
1198 /* permissive domain? */
1199 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1200 avd->flags |= AVD_FLAGS_PERMISSIVE;
1201
1202 tcontext = sidtab_search(sidtab, tsid);
1203 if (!tcontext) {
1204 pr_err("SELinux: %s: unrecognized SID %d\n",
1205 __func__, tsid);
1206 goto out;
1207 }
1208
1209 if (unlikely(!tclass)) {
1210 if (policydb->allow_unknown)
1211 goto allow;
1212 goto out;
1213 }
1214
1215 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1216 NULL);
1217 out:
1218 rcu_read_unlock();
1219 return;
1220allow:
1221 avd->allowed = 0xffffffff;
1222 goto out;
1223}
1224
1225/*
1226 * Write the security context string representation of
1227 * the context structure `context' into a dynamically
1228 * allocated string of the correct size. Set `*scontext'
1229 * to point to this string and set `*scontext_len' to
1230 * the length of the string.
1231 */
1232static int context_struct_to_string(struct policydb *p,
1233 struct context *context,
1234 char **scontext, u32 *scontext_len)
1235{
1236 char *scontextp;
1237
1238 if (scontext)
1239 *scontext = NULL;
1240 *scontext_len = 0;
1241
1242 if (context->len) {
1243 *scontext_len = context->len;
1244 if (scontext) {
1245 *scontext = kstrdup(context->str, GFP_ATOMIC);
1246 if (!(*scontext))
1247 return -ENOMEM;
1248 }
1249 return 0;
1250 }
1251
1252 /* Compute the size of the context. */
1253 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1254 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1255 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1256 *scontext_len += mls_compute_context_len(p, context);
1257
1258 if (!scontext)
1259 return 0;
1260
1261 /* Allocate space for the context; caller must free this space. */
1262 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1263 if (!scontextp)
1264 return -ENOMEM;
1265 *scontext = scontextp;
1266
1267 /*
1268 * Copy the user name, role name and type name into the context.
1269 */
1270 scontextp += sprintf(scontextp, "%s:%s:%s",
1271 sym_name(p, SYM_USERS, context->user - 1),
1272 sym_name(p, SYM_ROLES, context->role - 1),
1273 sym_name(p, SYM_TYPES, context->type - 1));
1274
1275 mls_sid_to_context(p, context, &scontextp);
1276
1277 *scontextp = 0;
1278
1279 return 0;
1280}
1281
1282static int sidtab_entry_to_string(struct policydb *p,
1283 struct sidtab *sidtab,
1284 struct sidtab_entry *entry,
1285 char **scontext, u32 *scontext_len)
1286{
1287 int rc = sidtab_sid2str_get(sidtab, entry, scontext, scontext_len);
1288
1289 if (rc != -ENOENT)
1290 return rc;
1291
1292 rc = context_struct_to_string(p, &entry->context, scontext,
1293 scontext_len);
1294 if (!rc && scontext)
1295 sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len);
1296 return rc;
1297}
1298
1299#include "initial_sid_to_string.h"
1300
1301int security_sidtab_hash_stats(struct selinux_state *state, char *page)
1302{
1303 struct selinux_policy *policy;
1304 int rc;
1305
1306 if (!selinux_initialized(state)) {
1307 pr_err("SELinux: %s: called before initial load_policy\n",
1308 __func__);
1309 return -EINVAL;
1310 }
1311
1312 rcu_read_lock();
1313 policy = rcu_dereference(state->policy);
1314 rc = sidtab_hash_stats(policy->sidtab, page);
1315 rcu_read_unlock();
1316
1317 return rc;
1318}
1319
1320const char *security_get_initial_sid_context(u32 sid)
1321{
1322 if (unlikely(sid > SECINITSID_NUM))
1323 return NULL;
1324 return initial_sid_to_string[sid];
1325}
1326
1327static int security_sid_to_context_core(struct selinux_state *state,
1328 u32 sid, char **scontext,
1329 u32 *scontext_len, int force,
1330 int only_invalid)
1331{
1332 struct selinux_policy *policy;
1333 struct policydb *policydb;
1334 struct sidtab *sidtab;
1335 struct sidtab_entry *entry;
1336 int rc = 0;
1337
1338 if (scontext)
1339 *scontext = NULL;
1340 *scontext_len = 0;
1341
1342 if (!selinux_initialized(state)) {
1343 if (sid <= SECINITSID_NUM) {
1344 char *scontextp;
1345 const char *s = initial_sid_to_string[sid];
1346
1347 if (!s)
1348 return -EINVAL;
1349 *scontext_len = strlen(s) + 1;
1350 if (!scontext)
1351 return 0;
1352 scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC);
1353 if (!scontextp)
1354 return -ENOMEM;
1355 *scontext = scontextp;
1356 return 0;
1357 }
1358 pr_err("SELinux: %s: called before initial "
1359 "load_policy on unknown SID %d\n", __func__, sid);
1360 return -EINVAL;
1361 }
1362 rcu_read_lock();
1363 policy = rcu_dereference(state->policy);
1364 policydb = &policy->policydb;
1365 sidtab = policy->sidtab;
1366
1367 if (force)
1368 entry = sidtab_search_entry_force(sidtab, sid);
1369 else
1370 entry = sidtab_search_entry(sidtab, sid);
1371 if (!entry) {
1372 pr_err("SELinux: %s: unrecognized SID %d\n",
1373 __func__, sid);
1374 rc = -EINVAL;
1375 goto out_unlock;
1376 }
1377 if (only_invalid && !entry->context.len)
1378 goto out_unlock;
1379
1380 rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext,
1381 scontext_len);
1382
1383out_unlock:
1384 rcu_read_unlock();
1385 return rc;
1386
1387}
1388
1389/**
1390 * security_sid_to_context - Obtain a context for a given SID.
1391 * @state: SELinux state
1392 * @sid: security identifier, SID
1393 * @scontext: security context
1394 * @scontext_len: length in bytes
1395 *
1396 * Write the string representation of the context associated with @sid
1397 * into a dynamically allocated string of the correct size. Set @scontext
1398 * to point to this string and set @scontext_len to the length of the string.
1399 */
1400int security_sid_to_context(struct selinux_state *state,
1401 u32 sid, char **scontext, u32 *scontext_len)
1402{
1403 return security_sid_to_context_core(state, sid, scontext,
1404 scontext_len, 0, 0);
1405}
1406
1407int security_sid_to_context_force(struct selinux_state *state, u32 sid,
1408 char **scontext, u32 *scontext_len)
1409{
1410 return security_sid_to_context_core(state, sid, scontext,
1411 scontext_len, 1, 0);
1412}
1413
1414/**
1415 * security_sid_to_context_inval - Obtain a context for a given SID if it
1416 * is invalid.
1417 * @state: SELinux state
1418 * @sid: security identifier, SID
1419 * @scontext: security context
1420 * @scontext_len: length in bytes
1421 *
1422 * Write the string representation of the context associated with @sid
1423 * into a dynamically allocated string of the correct size, but only if the
1424 * context is invalid in the current policy. Set @scontext to point to
1425 * this string (or NULL if the context is valid) and set @scontext_len to
1426 * the length of the string (or 0 if the context is valid).
1427 */
1428int security_sid_to_context_inval(struct selinux_state *state, u32 sid,
1429 char **scontext, u32 *scontext_len)
1430{
1431 return security_sid_to_context_core(state, sid, scontext,
1432 scontext_len, 1, 1);
1433}
1434
1435/*
1436 * Caveat: Mutates scontext.
1437 */
1438static int string_to_context_struct(struct policydb *pol,
1439 struct sidtab *sidtabp,
1440 char *scontext,
1441 struct context *ctx,
1442 u32 def_sid)
1443{
1444 struct role_datum *role;
1445 struct type_datum *typdatum;
1446 struct user_datum *usrdatum;
1447 char *scontextp, *p, oldc;
1448 int rc = 0;
1449
1450 context_init(ctx);
1451
1452 /* Parse the security context. */
1453
1454 rc = -EINVAL;
1455 scontextp = (char *) scontext;
1456
1457 /* Extract the user. */
1458 p = scontextp;
1459 while (*p && *p != ':')
1460 p++;
1461
1462 if (*p == 0)
1463 goto out;
1464
1465 *p++ = 0;
1466
1467 usrdatum = symtab_search(&pol->p_users, scontextp);
1468 if (!usrdatum)
1469 goto out;
1470
1471 ctx->user = usrdatum->value;
1472
1473 /* Extract role. */
1474 scontextp = p;
1475 while (*p && *p != ':')
1476 p++;
1477
1478 if (*p == 0)
1479 goto out;
1480
1481 *p++ = 0;
1482
1483 role = symtab_search(&pol->p_roles, scontextp);
1484 if (!role)
1485 goto out;
1486 ctx->role = role->value;
1487
1488 /* Extract type. */
1489 scontextp = p;
1490 while (*p && *p != ':')
1491 p++;
1492 oldc = *p;
1493 *p++ = 0;
1494
1495 typdatum = symtab_search(&pol->p_types, scontextp);
1496 if (!typdatum || typdatum->attribute)
1497 goto out;
1498
1499 ctx->type = typdatum->value;
1500
1501 rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid);
1502 if (rc)
1503 goto out;
1504
1505 /* Check the validity of the new context. */
1506 rc = -EINVAL;
1507 if (!policydb_context_isvalid(pol, ctx))
1508 goto out;
1509 rc = 0;
1510out:
1511 if (rc)
1512 context_destroy(ctx);
1513 return rc;
1514}
1515
1516static int security_context_to_sid_core(struct selinux_state *state,
1517 const char *scontext, u32 scontext_len,
1518 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1519 int force)
1520{
1521 struct selinux_policy *policy;
1522 struct policydb *policydb;
1523 struct sidtab *sidtab;
1524 char *scontext2, *str = NULL;
1525 struct context context;
1526 int rc = 0;
1527
1528 /* An empty security context is never valid. */
1529 if (!scontext_len)
1530 return -EINVAL;
1531
1532 /* Copy the string to allow changes and ensure a NUL terminator */
1533 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags);
1534 if (!scontext2)
1535 return -ENOMEM;
1536
1537 if (!selinux_initialized(state)) {
1538 int i;
1539
1540 for (i = 1; i < SECINITSID_NUM; i++) {
1541 const char *s = initial_sid_to_string[i];
1542
1543 if (s && !strcmp(s, scontext2)) {
1544 *sid = i;
1545 goto out;
1546 }
1547 }
1548 *sid = SECINITSID_KERNEL;
1549 goto out;
1550 }
1551 *sid = SECSID_NULL;
1552
1553 if (force) {
1554 /* Save another copy for storing in uninterpreted form */
1555 rc = -ENOMEM;
1556 str = kstrdup(scontext2, gfp_flags);
1557 if (!str)
1558 goto out;
1559 }
1560retry:
1561 rcu_read_lock();
1562 policy = rcu_dereference(state->policy);
1563 policydb = &policy->policydb;
1564 sidtab = policy->sidtab;
1565 rc = string_to_context_struct(policydb, sidtab, scontext2,
1566 &context, def_sid);
1567 if (rc == -EINVAL && force) {
1568 context.str = str;
1569 context.len = strlen(str) + 1;
1570 str = NULL;
1571 } else if (rc)
1572 goto out_unlock;
1573 rc = sidtab_context_to_sid(sidtab, &context, sid);
1574 if (rc == -ESTALE) {
1575 rcu_read_unlock();
1576 if (context.str) {
1577 str = context.str;
1578 context.str = NULL;
1579 }
1580 context_destroy(&context);
1581 goto retry;
1582 }
1583 context_destroy(&context);
1584out_unlock:
1585 rcu_read_unlock();
1586out:
1587 kfree(scontext2);
1588 kfree(str);
1589 return rc;
1590}
1591
1592/**
1593 * security_context_to_sid - Obtain a SID for a given security context.
1594 * @state: SELinux state
1595 * @scontext: security context
1596 * @scontext_len: length in bytes
1597 * @sid: security identifier, SID
1598 * @gfp: context for the allocation
1599 *
1600 * Obtains a SID associated with the security context that
1601 * has the string representation specified by @scontext.
1602 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1603 * memory is available, or 0 on success.
1604 */
1605int security_context_to_sid(struct selinux_state *state,
1606 const char *scontext, u32 scontext_len, u32 *sid,
1607 gfp_t gfp)
1608{
1609 return security_context_to_sid_core(state, scontext, scontext_len,
1610 sid, SECSID_NULL, gfp, 0);
1611}
1612
1613int security_context_str_to_sid(struct selinux_state *state,
1614 const char *scontext, u32 *sid, gfp_t gfp)
1615{
1616 return security_context_to_sid(state, scontext, strlen(scontext),
1617 sid, gfp);
1618}
1619
1620/**
1621 * security_context_to_sid_default - Obtain a SID for a given security context,
1622 * falling back to specified default if needed.
1623 *
1624 * @state: SELinux state
1625 * @scontext: security context
1626 * @scontext_len: length in bytes
1627 * @sid: security identifier, SID
1628 * @def_sid: default SID to assign on error
1629 *
1630 * Obtains a SID associated with the security context that
1631 * has the string representation specified by @scontext.
1632 * The default SID is passed to the MLS layer to be used to allow
1633 * kernel labeling of the MLS field if the MLS field is not present
1634 * (for upgrading to MLS without full relabel).
1635 * Implicitly forces adding of the context even if it cannot be mapped yet.
1636 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1637 * memory is available, or 0 on success.
1638 */
1639int security_context_to_sid_default(struct selinux_state *state,
1640 const char *scontext, u32 scontext_len,
1641 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1642{
1643 return security_context_to_sid_core(state, scontext, scontext_len,
1644 sid, def_sid, gfp_flags, 1);
1645}
1646
1647int security_context_to_sid_force(struct selinux_state *state,
1648 const char *scontext, u32 scontext_len,
1649 u32 *sid)
1650{
1651 return security_context_to_sid_core(state, scontext, scontext_len,
1652 sid, SECSID_NULL, GFP_KERNEL, 1);
1653}
1654
1655static int compute_sid_handle_invalid_context(
1656 struct selinux_state *state,
1657 struct selinux_policy *policy,
1658 struct sidtab_entry *sentry,
1659 struct sidtab_entry *tentry,
1660 u16 tclass,
1661 struct context *newcontext)
1662{
1663 struct policydb *policydb = &policy->policydb;
1664 struct sidtab *sidtab = policy->sidtab;
1665 char *s = NULL, *t = NULL, *n = NULL;
1666 u32 slen, tlen, nlen;
1667 struct audit_buffer *ab;
1668
1669 if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen))
1670 goto out;
1671 if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen))
1672 goto out;
1673 if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1674 goto out;
1675 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR);
1676 audit_log_format(ab,
1677 "op=security_compute_sid invalid_context=");
1678 /* no need to record the NUL with untrusted strings */
1679 audit_log_n_untrustedstring(ab, n, nlen - 1);
1680 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s",
1681 s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1682 audit_log_end(ab);
1683out:
1684 kfree(s);
1685 kfree(t);
1686 kfree(n);
1687 if (!enforcing_enabled(state))
1688 return 0;
1689 return -EACCES;
1690}
1691
1692static void filename_compute_type(struct policydb *policydb,
1693 struct context *newcontext,
1694 u32 stype, u32 ttype, u16 tclass,
1695 const char *objname)
1696{
1697 struct filename_trans_key ft;
1698 struct filename_trans_datum *datum;
1699
1700 /*
1701 * Most filename trans rules are going to live in specific directories
1702 * like /dev or /var/run. This bitmap will quickly skip rule searches
1703 * if the ttype does not contain any rules.
1704 */
1705 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1706 return;
1707
1708 ft.ttype = ttype;
1709 ft.tclass = tclass;
1710 ft.name = objname;
1711
1712 datum = policydb_filenametr_search(policydb, &ft);
1713 while (datum) {
1714 if (ebitmap_get_bit(&datum->stypes, stype - 1)) {
1715 newcontext->type = datum->otype;
1716 return;
1717 }
1718 datum = datum->next;
1719 }
1720}
1721
1722static int security_compute_sid(struct selinux_state *state,
1723 u32 ssid,
1724 u32 tsid,
1725 u16 orig_tclass,
1726 u32 specified,
1727 const char *objname,
1728 u32 *out_sid,
1729 bool kern)
1730{
1731 struct selinux_policy *policy;
1732 struct policydb *policydb;
1733 struct sidtab *sidtab;
1734 struct class_datum *cladatum;
1735 struct context *scontext, *tcontext, newcontext;
1736 struct sidtab_entry *sentry, *tentry;
1737 struct avtab_key avkey;
1738 struct avtab_datum *avdatum;
1739 struct avtab_node *node;
1740 u16 tclass;
1741 int rc = 0;
1742 bool sock;
1743
1744 if (!selinux_initialized(state)) {
1745 switch (orig_tclass) {
1746 case SECCLASS_PROCESS: /* kernel value */
1747 *out_sid = ssid;
1748 break;
1749 default:
1750 *out_sid = tsid;
1751 break;
1752 }
1753 goto out;
1754 }
1755
1756retry:
1757 cladatum = NULL;
1758 context_init(&newcontext);
1759
1760 rcu_read_lock();
1761
1762 policy = rcu_dereference(state->policy);
1763
1764 if (kern) {
1765 tclass = unmap_class(&policy->map, orig_tclass);
1766 sock = security_is_socket_class(orig_tclass);
1767 } else {
1768 tclass = orig_tclass;
1769 sock = security_is_socket_class(map_class(&policy->map,
1770 tclass));
1771 }
1772
1773 policydb = &policy->policydb;
1774 sidtab = policy->sidtab;
1775
1776 sentry = sidtab_search_entry(sidtab, ssid);
1777 if (!sentry) {
1778 pr_err("SELinux: %s: unrecognized SID %d\n",
1779 __func__, ssid);
1780 rc = -EINVAL;
1781 goto out_unlock;
1782 }
1783 tentry = sidtab_search_entry(sidtab, tsid);
1784 if (!tentry) {
1785 pr_err("SELinux: %s: unrecognized SID %d\n",
1786 __func__, tsid);
1787 rc = -EINVAL;
1788 goto out_unlock;
1789 }
1790
1791 scontext = &sentry->context;
1792 tcontext = &tentry->context;
1793
1794 if (tclass && tclass <= policydb->p_classes.nprim)
1795 cladatum = policydb->class_val_to_struct[tclass - 1];
1796
1797 /* Set the user identity. */
1798 switch (specified) {
1799 case AVTAB_TRANSITION:
1800 case AVTAB_CHANGE:
1801 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1802 newcontext.user = tcontext->user;
1803 } else {
1804 /* notice this gets both DEFAULT_SOURCE and unset */
1805 /* Use the process user identity. */
1806 newcontext.user = scontext->user;
1807 }
1808 break;
1809 case AVTAB_MEMBER:
1810 /* Use the related object owner. */
1811 newcontext.user = tcontext->user;
1812 break;
1813 }
1814
1815 /* Set the role to default values. */
1816 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1817 newcontext.role = scontext->role;
1818 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1819 newcontext.role = tcontext->role;
1820 } else {
1821 if ((tclass == policydb->process_class) || sock)
1822 newcontext.role = scontext->role;
1823 else
1824 newcontext.role = OBJECT_R_VAL;
1825 }
1826
1827 /* Set the type to default values. */
1828 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1829 newcontext.type = scontext->type;
1830 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1831 newcontext.type = tcontext->type;
1832 } else {
1833 if ((tclass == policydb->process_class) || sock) {
1834 /* Use the type of process. */
1835 newcontext.type = scontext->type;
1836 } else {
1837 /* Use the type of the related object. */
1838 newcontext.type = tcontext->type;
1839 }
1840 }
1841
1842 /* Look for a type transition/member/change rule. */
1843 avkey.source_type = scontext->type;
1844 avkey.target_type = tcontext->type;
1845 avkey.target_class = tclass;
1846 avkey.specified = specified;
1847 avdatum = avtab_search(&policydb->te_avtab, &avkey);
1848
1849 /* If no permanent rule, also check for enabled conditional rules */
1850 if (!avdatum) {
1851 node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1852 for (; node; node = avtab_search_node_next(node, specified)) {
1853 if (node->key.specified & AVTAB_ENABLED) {
1854 avdatum = &node->datum;
1855 break;
1856 }
1857 }
1858 }
1859
1860 if (avdatum) {
1861 /* Use the type from the type transition/member/change rule. */
1862 newcontext.type = avdatum->u.data;
1863 }
1864
1865 /* if we have a objname this is a file trans check so check those rules */
1866 if (objname)
1867 filename_compute_type(policydb, &newcontext, scontext->type,
1868 tcontext->type, tclass, objname);
1869
1870 /* Check for class-specific changes. */
1871 if (specified & AVTAB_TRANSITION) {
1872 /* Look for a role transition rule. */
1873 struct role_trans_datum *rtd;
1874 struct role_trans_key rtk = {
1875 .role = scontext->role,
1876 .type = tcontext->type,
1877 .tclass = tclass,
1878 };
1879
1880 rtd = policydb_roletr_search(policydb, &rtk);
1881 if (rtd)
1882 newcontext.role = rtd->new_role;
1883 }
1884
1885 /* Set the MLS attributes.
1886 This is done last because it may allocate memory. */
1887 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1888 &newcontext, sock);
1889 if (rc)
1890 goto out_unlock;
1891
1892 /* Check the validity of the context. */
1893 if (!policydb_context_isvalid(policydb, &newcontext)) {
1894 rc = compute_sid_handle_invalid_context(state, policy, sentry,
1895 tentry, tclass,
1896 &newcontext);
1897 if (rc)
1898 goto out_unlock;
1899 }
1900 /* Obtain the sid for the context. */
1901 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1902 if (rc == -ESTALE) {
1903 rcu_read_unlock();
1904 context_destroy(&newcontext);
1905 goto retry;
1906 }
1907out_unlock:
1908 rcu_read_unlock();
1909 context_destroy(&newcontext);
1910out:
1911 return rc;
1912}
1913
1914/**
1915 * security_transition_sid - Compute the SID for a new subject/object.
1916 * @state: SELinux state
1917 * @ssid: source security identifier
1918 * @tsid: target security identifier
1919 * @tclass: target security class
1920 * @out_sid: security identifier for new subject/object
1921 *
1922 * Compute a SID to use for labeling a new subject or object in the
1923 * class @tclass based on a SID pair (@ssid, @tsid).
1924 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1925 * if insufficient memory is available, or %0 if the new SID was
1926 * computed successfully.
1927 */
1928int security_transition_sid(struct selinux_state *state,
1929 u32 ssid, u32 tsid, u16 tclass,
1930 const struct qstr *qstr, u32 *out_sid)
1931{
1932 return security_compute_sid(state, ssid, tsid, tclass,
1933 AVTAB_TRANSITION,
1934 qstr ? qstr->name : NULL, out_sid, true);
1935}
1936
1937int security_transition_sid_user(struct selinux_state *state,
1938 u32 ssid, u32 tsid, u16 tclass,
1939 const char *objname, u32 *out_sid)
1940{
1941 return security_compute_sid(state, ssid, tsid, tclass,
1942 AVTAB_TRANSITION,
1943 objname, out_sid, false);
1944}
1945
1946/**
1947 * security_member_sid - Compute the SID for member selection.
1948 * @ssid: source security identifier
1949 * @tsid: target security identifier
1950 * @tclass: target security class
1951 * @out_sid: security identifier for selected member
1952 *
1953 * Compute a SID to use when selecting a member of a polyinstantiated
1954 * object of class @tclass based on a SID pair (@ssid, @tsid).
1955 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1956 * if insufficient memory is available, or %0 if the SID was
1957 * computed successfully.
1958 */
1959int security_member_sid(struct selinux_state *state,
1960 u32 ssid,
1961 u32 tsid,
1962 u16 tclass,
1963 u32 *out_sid)
1964{
1965 return security_compute_sid(state, ssid, tsid, tclass,
1966 AVTAB_MEMBER, NULL,
1967 out_sid, false);
1968}
1969
1970/**
1971 * security_change_sid - Compute the SID for object relabeling.
1972 * @state: SELinux state
1973 * @ssid: source security identifier
1974 * @tsid: target security identifier
1975 * @tclass: target security class
1976 * @out_sid: security identifier for selected member
1977 *
1978 * Compute a SID to use for relabeling an object of class @tclass
1979 * based on a SID pair (@ssid, @tsid).
1980 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1981 * if insufficient memory is available, or %0 if the SID was
1982 * computed successfully.
1983 */
1984int security_change_sid(struct selinux_state *state,
1985 u32 ssid,
1986 u32 tsid,
1987 u16 tclass,
1988 u32 *out_sid)
1989{
1990 return security_compute_sid(state,
1991 ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1992 out_sid, false);
1993}
1994
1995static inline int convert_context_handle_invalid_context(
1996 struct selinux_state *state,
1997 struct policydb *policydb,
1998 struct context *context)
1999{
2000 char *s;
2001 u32 len;
2002
2003 if (enforcing_enabled(state))
2004 return -EINVAL;
2005
2006 if (!context_struct_to_string(policydb, context, &s, &len)) {
2007 pr_warn("SELinux: Context %s would be invalid if enforcing\n",
2008 s);
2009 kfree(s);
2010 }
2011 return 0;
2012}
2013
2014/*
2015 * Convert the values in the security context
2016 * structure `oldc' from the values specified
2017 * in the policy `p->oldp' to the values specified
2018 * in the policy `p->newp', storing the new context
2019 * in `newc'. Verify that the context is valid
2020 * under the new policy.
2021 */
2022static int convert_context(struct context *oldc, struct context *newc, void *p)
2023{
2024 struct convert_context_args *args;
2025 struct ocontext *oc;
2026 struct role_datum *role;
2027 struct type_datum *typdatum;
2028 struct user_datum *usrdatum;
2029 char *s;
2030 u32 len;
2031 int rc;
2032
2033 args = p;
2034
2035 if (oldc->str) {
2036 s = kstrdup(oldc->str, GFP_KERNEL);
2037 if (!s)
2038 return -ENOMEM;
2039
2040 rc = string_to_context_struct(args->newp, NULL, s,
2041 newc, SECSID_NULL);
2042 if (rc == -EINVAL) {
2043 /*
2044 * Retain string representation for later mapping.
2045 *
2046 * IMPORTANT: We need to copy the contents of oldc->str
2047 * back into s again because string_to_context_struct()
2048 * may have garbled it.
2049 */
2050 memcpy(s, oldc->str, oldc->len);
2051 context_init(newc);
2052 newc->str = s;
2053 newc->len = oldc->len;
2054 return 0;
2055 }
2056 kfree(s);
2057 if (rc) {
2058 /* Other error condition, e.g. ENOMEM. */
2059 pr_err("SELinux: Unable to map context %s, rc = %d.\n",
2060 oldc->str, -rc);
2061 return rc;
2062 }
2063 pr_info("SELinux: Context %s became valid (mapped).\n",
2064 oldc->str);
2065 return 0;
2066 }
2067
2068 context_init(newc);
2069
2070 /* Convert the user. */
2071 usrdatum = symtab_search(&args->newp->p_users,
2072 sym_name(args->oldp,
2073 SYM_USERS, oldc->user - 1));
2074 if (!usrdatum)
2075 goto bad;
2076 newc->user = usrdatum->value;
2077
2078 /* Convert the role. */
2079 role = symtab_search(&args->newp->p_roles,
2080 sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
2081 if (!role)
2082 goto bad;
2083 newc->role = role->value;
2084
2085 /* Convert the type. */
2086 typdatum = symtab_search(&args->newp->p_types,
2087 sym_name(args->oldp,
2088 SYM_TYPES, oldc->type - 1));
2089 if (!typdatum)
2090 goto bad;
2091 newc->type = typdatum->value;
2092
2093 /* Convert the MLS fields if dealing with MLS policies */
2094 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2095 rc = mls_convert_context(args->oldp, args->newp, oldc, newc);
2096 if (rc)
2097 goto bad;
2098 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2099 /*
2100 * Switching between non-MLS and MLS policy:
2101 * ensure that the MLS fields of the context for all
2102 * existing entries in the sidtab are filled in with a
2103 * suitable default value, likely taken from one of the
2104 * initial SIDs.
2105 */
2106 oc = args->newp->ocontexts[OCON_ISID];
2107 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2108 oc = oc->next;
2109 if (!oc) {
2110 pr_err("SELinux: unable to look up"
2111 " the initial SIDs list\n");
2112 goto bad;
2113 }
2114 rc = mls_range_set(newc, &oc->context[0].range);
2115 if (rc)
2116 goto bad;
2117 }
2118
2119 /* Check the validity of the new context. */
2120 if (!policydb_context_isvalid(args->newp, newc)) {
2121 rc = convert_context_handle_invalid_context(args->state,
2122 args->oldp,
2123 oldc);
2124 if (rc)
2125 goto bad;
2126 }
2127
2128 return 0;
2129bad:
2130 /* Map old representation to string and save it. */
2131 rc = context_struct_to_string(args->oldp, oldc, &s, &len);
2132 if (rc)
2133 return rc;
2134 context_destroy(newc);
2135 newc->str = s;
2136 newc->len = len;
2137 pr_info("SELinux: Context %s became invalid (unmapped).\n",
2138 newc->str);
2139 return 0;
2140}
2141
2142static void security_load_policycaps(struct selinux_state *state,
2143 struct selinux_policy *policy)
2144{
2145 struct policydb *p;
2146 unsigned int i;
2147 struct ebitmap_node *node;
2148
2149 p = &policy->policydb;
2150
2151 for (i = 0; i < ARRAY_SIZE(state->policycap); i++)
2152 WRITE_ONCE(state->policycap[i],
2153 ebitmap_get_bit(&p->policycaps, i));
2154
2155 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2156 pr_info("SELinux: policy capability %s=%d\n",
2157 selinux_policycap_names[i],
2158 ebitmap_get_bit(&p->policycaps, i));
2159
2160 ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2161 if (i >= ARRAY_SIZE(selinux_policycap_names))
2162 pr_info("SELinux: unknown policy capability %u\n",
2163 i);
2164 }
2165}
2166
2167static int security_preserve_bools(struct selinux_policy *oldpolicy,
2168 struct selinux_policy *newpolicy);
2169
2170static void selinux_policy_free(struct selinux_policy *policy)
2171{
2172 if (!policy)
2173 return;
2174
2175 sidtab_destroy(policy->sidtab);
2176 kfree(policy->map.mapping);
2177 policydb_destroy(&policy->policydb);
2178 kfree(policy->sidtab);
2179 kfree(policy);
2180}
2181
2182static void selinux_policy_cond_free(struct selinux_policy *policy)
2183{
2184 cond_policydb_destroy_dup(&policy->policydb);
2185 kfree(policy);
2186}
2187
2188void selinux_policy_cancel(struct selinux_state *state,
2189 struct selinux_load_state *load_state)
2190{
2191 struct selinux_policy *oldpolicy;
2192
2193 oldpolicy = rcu_dereference_protected(state->policy,
2194 lockdep_is_held(&state->policy_mutex));
2195
2196 sidtab_cancel_convert(oldpolicy->sidtab);
2197 selinux_policy_free(load_state->policy);
2198 kfree(load_state->convert_data);
2199}
2200
2201static void selinux_notify_policy_change(struct selinux_state *state,
2202 u32 seqno)
2203{
2204 /* Flush external caches and notify userspace of policy load */
2205 avc_ss_reset(state->avc, seqno);
2206 selnl_notify_policyload(seqno);
2207 selinux_status_update_policyload(state, seqno);
2208 selinux_netlbl_cache_invalidate();
2209 selinux_xfrm_notify_policyload();
2210 selinux_ima_measure_state_locked(state);
2211}
2212
2213void selinux_policy_commit(struct selinux_state *state,
2214 struct selinux_load_state *load_state)
2215{
2216 struct selinux_policy *oldpolicy, *newpolicy = load_state->policy;
2217 unsigned long flags;
2218 u32 seqno;
2219
2220 oldpolicy = rcu_dereference_protected(state->policy,
2221 lockdep_is_held(&state->policy_mutex));
2222
2223 /* If switching between different policy types, log MLS status */
2224 if (oldpolicy) {
2225 if (oldpolicy->policydb.mls_enabled && !newpolicy->policydb.mls_enabled)
2226 pr_info("SELinux: Disabling MLS support...\n");
2227 else if (!oldpolicy->policydb.mls_enabled && newpolicy->policydb.mls_enabled)
2228 pr_info("SELinux: Enabling MLS support...\n");
2229 }
2230
2231 /* Set latest granting seqno for new policy. */
2232 if (oldpolicy)
2233 newpolicy->latest_granting = oldpolicy->latest_granting + 1;
2234 else
2235 newpolicy->latest_granting = 1;
2236 seqno = newpolicy->latest_granting;
2237
2238 /* Install the new policy. */
2239 if (oldpolicy) {
2240 sidtab_freeze_begin(oldpolicy->sidtab, &flags);
2241 rcu_assign_pointer(state->policy, newpolicy);
2242 sidtab_freeze_end(oldpolicy->sidtab, &flags);
2243 } else {
2244 rcu_assign_pointer(state->policy, newpolicy);
2245 }
2246
2247 /* Load the policycaps from the new policy */
2248 security_load_policycaps(state, newpolicy);
2249
2250 if (!selinux_initialized(state)) {
2251 /*
2252 * After first policy load, the security server is
2253 * marked as initialized and ready to handle requests and
2254 * any objects created prior to policy load are then labeled.
2255 */
2256 selinux_mark_initialized(state);
2257 selinux_complete_init();
2258 }
2259
2260 /* Free the old policy */
2261 synchronize_rcu();
2262 selinux_policy_free(oldpolicy);
2263 kfree(load_state->convert_data);
2264
2265 /* Notify others of the policy change */
2266 selinux_notify_policy_change(state, seqno);
2267}
2268
2269/**
2270 * security_load_policy - Load a security policy configuration.
2271 * @state: SELinux state
2272 * @data: binary policy data
2273 * @len: length of data in bytes
2274 *
2275 * Load a new set of security policy configuration data,
2276 * validate it and convert the SID table as necessary.
2277 * This function will flush the access vector cache after
2278 * loading the new policy.
2279 */
2280int security_load_policy(struct selinux_state *state, void *data, size_t len,
2281 struct selinux_load_state *load_state)
2282{
2283 struct selinux_policy *newpolicy, *oldpolicy;
2284 struct selinux_policy_convert_data *convert_data;
2285 int rc = 0;
2286 struct policy_file file = { data, len }, *fp = &file;
2287
2288 newpolicy = kzalloc(sizeof(*newpolicy), GFP_KERNEL);
2289 if (!newpolicy)
2290 return -ENOMEM;
2291
2292 newpolicy->sidtab = kzalloc(sizeof(*newpolicy->sidtab), GFP_KERNEL);
2293 if (!newpolicy->sidtab) {
2294 rc = -ENOMEM;
2295 goto err_policy;
2296 }
2297
2298 rc = policydb_read(&newpolicy->policydb, fp);
2299 if (rc)
2300 goto err_sidtab;
2301
2302 newpolicy->policydb.len = len;
2303 rc = selinux_set_mapping(&newpolicy->policydb, secclass_map,
2304 &newpolicy->map);
2305 if (rc)
2306 goto err_policydb;
2307
2308 rc = policydb_load_isids(&newpolicy->policydb, newpolicy->sidtab);
2309 if (rc) {
2310 pr_err("SELinux: unable to load the initial SIDs\n");
2311 goto err_mapping;
2312 }
2313
2314 if (!selinux_initialized(state)) {
2315 /* First policy load, so no need to preserve state from old policy */
2316 load_state->policy = newpolicy;
2317 load_state->convert_data = NULL;
2318 return 0;
2319 }
2320
2321 oldpolicy = rcu_dereference_protected(state->policy,
2322 lockdep_is_held(&state->policy_mutex));
2323
2324 /* Preserve active boolean values from the old policy */
2325 rc = security_preserve_bools(oldpolicy, newpolicy);
2326 if (rc) {
2327 pr_err("SELinux: unable to preserve booleans\n");
2328 goto err_free_isids;
2329 }
2330
2331 convert_data = kmalloc(sizeof(*convert_data), GFP_KERNEL);
2332 if (!convert_data) {
2333 rc = -ENOMEM;
2334 goto err_free_isids;
2335 }
2336
2337 /*
2338 * Convert the internal representations of contexts
2339 * in the new SID table.
2340 */
2341 convert_data->args.state = state;
2342 convert_data->args.oldp = &oldpolicy->policydb;
2343 convert_data->args.newp = &newpolicy->policydb;
2344
2345 convert_data->sidtab_params.func = convert_context;
2346 convert_data->sidtab_params.args = &convert_data->args;
2347 convert_data->sidtab_params.target = newpolicy->sidtab;
2348
2349 rc = sidtab_convert(oldpolicy->sidtab, &convert_data->sidtab_params);
2350 if (rc) {
2351 pr_err("SELinux: unable to convert the internal"
2352 " representation of contexts in the new SID"
2353 " table\n");
2354 goto err_free_convert_data;
2355 }
2356
2357 load_state->policy = newpolicy;
2358 load_state->convert_data = convert_data;
2359 return 0;
2360
2361err_free_convert_data:
2362 kfree(convert_data);
2363err_free_isids:
2364 sidtab_destroy(newpolicy->sidtab);
2365err_mapping:
2366 kfree(newpolicy->map.mapping);
2367err_policydb:
2368 policydb_destroy(&newpolicy->policydb);
2369err_sidtab:
2370 kfree(newpolicy->sidtab);
2371err_policy:
2372 kfree(newpolicy);
2373
2374 return rc;
2375}
2376
2377/**
2378 * security_port_sid - Obtain the SID for a port.
2379 * @state: SELinux state
2380 * @protocol: protocol number
2381 * @port: port number
2382 * @out_sid: security identifier
2383 */
2384int security_port_sid(struct selinux_state *state,
2385 u8 protocol, u16 port, u32 *out_sid)
2386{
2387 struct selinux_policy *policy;
2388 struct policydb *policydb;
2389 struct sidtab *sidtab;
2390 struct ocontext *c;
2391 int rc;
2392
2393 if (!selinux_initialized(state)) {
2394 *out_sid = SECINITSID_PORT;
2395 return 0;
2396 }
2397
2398retry:
2399 rc = 0;
2400 rcu_read_lock();
2401 policy = rcu_dereference(state->policy);
2402 policydb = &policy->policydb;
2403 sidtab = policy->sidtab;
2404
2405 c = policydb->ocontexts[OCON_PORT];
2406 while (c) {
2407 if (c->u.port.protocol == protocol &&
2408 c->u.port.low_port <= port &&
2409 c->u.port.high_port >= port)
2410 break;
2411 c = c->next;
2412 }
2413
2414 if (c) {
2415 if (!c->sid[0]) {
2416 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2417 &c->sid[0]);
2418 if (rc == -ESTALE) {
2419 rcu_read_unlock();
2420 goto retry;
2421 }
2422 if (rc)
2423 goto out;
2424 }
2425 *out_sid = c->sid[0];
2426 } else {
2427 *out_sid = SECINITSID_PORT;
2428 }
2429
2430out:
2431 rcu_read_unlock();
2432 return rc;
2433}
2434
2435/**
2436 * security_ib_pkey_sid - Obtain the SID for a pkey.
2437 * @state: SELinux state
2438 * @subnet_prefix: Subnet Prefix
2439 * @pkey_num: pkey number
2440 * @out_sid: security identifier
2441 */
2442int security_ib_pkey_sid(struct selinux_state *state,
2443 u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2444{
2445 struct selinux_policy *policy;
2446 struct policydb *policydb;
2447 struct sidtab *sidtab;
2448 struct ocontext *c;
2449 int rc;
2450
2451 if (!selinux_initialized(state)) {
2452 *out_sid = SECINITSID_UNLABELED;
2453 return 0;
2454 }
2455
2456retry:
2457 rc = 0;
2458 rcu_read_lock();
2459 policy = rcu_dereference(state->policy);
2460 policydb = &policy->policydb;
2461 sidtab = policy->sidtab;
2462
2463 c = policydb->ocontexts[OCON_IBPKEY];
2464 while (c) {
2465 if (c->u.ibpkey.low_pkey <= pkey_num &&
2466 c->u.ibpkey.high_pkey >= pkey_num &&
2467 c->u.ibpkey.subnet_prefix == subnet_prefix)
2468 break;
2469
2470 c = c->next;
2471 }
2472
2473 if (c) {
2474 if (!c->sid[0]) {
2475 rc = sidtab_context_to_sid(sidtab,
2476 &c->context[0],
2477 &c->sid[0]);
2478 if (rc == -ESTALE) {
2479 rcu_read_unlock();
2480 goto retry;
2481 }
2482 if (rc)
2483 goto out;
2484 }
2485 *out_sid = c->sid[0];
2486 } else
2487 *out_sid = SECINITSID_UNLABELED;
2488
2489out:
2490 rcu_read_unlock();
2491 return rc;
2492}
2493
2494/**
2495 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2496 * @state: SELinux state
2497 * @dev_name: device name
2498 * @port: port number
2499 * @out_sid: security identifier
2500 */
2501int security_ib_endport_sid(struct selinux_state *state,
2502 const char *dev_name, u8 port_num, u32 *out_sid)
2503{
2504 struct selinux_policy *policy;
2505 struct policydb *policydb;
2506 struct sidtab *sidtab;
2507 struct ocontext *c;
2508 int rc;
2509
2510 if (!selinux_initialized(state)) {
2511 *out_sid = SECINITSID_UNLABELED;
2512 return 0;
2513 }
2514
2515retry:
2516 rc = 0;
2517 rcu_read_lock();
2518 policy = rcu_dereference(state->policy);
2519 policydb = &policy->policydb;
2520 sidtab = policy->sidtab;
2521
2522 c = policydb->ocontexts[OCON_IBENDPORT];
2523 while (c) {
2524 if (c->u.ibendport.port == port_num &&
2525 !strncmp(c->u.ibendport.dev_name,
2526 dev_name,
2527 IB_DEVICE_NAME_MAX))
2528 break;
2529
2530 c = c->next;
2531 }
2532
2533 if (c) {
2534 if (!c->sid[0]) {
2535 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2536 &c->sid[0]);
2537 if (rc == -ESTALE) {
2538 rcu_read_unlock();
2539 goto retry;
2540 }
2541 if (rc)
2542 goto out;
2543 }
2544 *out_sid = c->sid[0];
2545 } else
2546 *out_sid = SECINITSID_UNLABELED;
2547
2548out:
2549 rcu_read_unlock();
2550 return rc;
2551}
2552
2553/**
2554 * security_netif_sid - Obtain the SID for a network interface.
2555 * @state: SELinux state
2556 * @name: interface name
2557 * @if_sid: interface SID
2558 */
2559int security_netif_sid(struct selinux_state *state,
2560 char *name, u32 *if_sid)
2561{
2562 struct selinux_policy *policy;
2563 struct policydb *policydb;
2564 struct sidtab *sidtab;
2565 int rc;
2566 struct ocontext *c;
2567
2568 if (!selinux_initialized(state)) {
2569 *if_sid = SECINITSID_NETIF;
2570 return 0;
2571 }
2572
2573retry:
2574 rc = 0;
2575 rcu_read_lock();
2576 policy = rcu_dereference(state->policy);
2577 policydb = &policy->policydb;
2578 sidtab = policy->sidtab;
2579
2580 c = policydb->ocontexts[OCON_NETIF];
2581 while (c) {
2582 if (strcmp(name, c->u.name) == 0)
2583 break;
2584 c = c->next;
2585 }
2586
2587 if (c) {
2588 if (!c->sid[0] || !c->sid[1]) {
2589 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2590 &c->sid[0]);
2591 if (rc == -ESTALE) {
2592 rcu_read_unlock();
2593 goto retry;
2594 }
2595 if (rc)
2596 goto out;
2597 rc = sidtab_context_to_sid(sidtab, &c->context[1],
2598 &c->sid[1]);
2599 if (rc == -ESTALE) {
2600 rcu_read_unlock();
2601 goto retry;
2602 }
2603 if (rc)
2604 goto out;
2605 }
2606 *if_sid = c->sid[0];
2607 } else
2608 *if_sid = SECINITSID_NETIF;
2609
2610out:
2611 rcu_read_unlock();
2612 return rc;
2613}
2614
2615static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2616{
2617 int i, fail = 0;
2618
2619 for (i = 0; i < 4; i++)
2620 if (addr[i] != (input[i] & mask[i])) {
2621 fail = 1;
2622 break;
2623 }
2624
2625 return !fail;
2626}
2627
2628/**
2629 * security_node_sid - Obtain the SID for a node (host).
2630 * @state: SELinux state
2631 * @domain: communication domain aka address family
2632 * @addrp: address
2633 * @addrlen: address length in bytes
2634 * @out_sid: security identifier
2635 */
2636int security_node_sid(struct selinux_state *state,
2637 u16 domain,
2638 void *addrp,
2639 u32 addrlen,
2640 u32 *out_sid)
2641{
2642 struct selinux_policy *policy;
2643 struct policydb *policydb;
2644 struct sidtab *sidtab;
2645 int rc;
2646 struct ocontext *c;
2647
2648 if (!selinux_initialized(state)) {
2649 *out_sid = SECINITSID_NODE;
2650 return 0;
2651 }
2652
2653retry:
2654 rcu_read_lock();
2655 policy = rcu_dereference(state->policy);
2656 policydb = &policy->policydb;
2657 sidtab = policy->sidtab;
2658
2659 switch (domain) {
2660 case AF_INET: {
2661 u32 addr;
2662
2663 rc = -EINVAL;
2664 if (addrlen != sizeof(u32))
2665 goto out;
2666
2667 addr = *((u32 *)addrp);
2668
2669 c = policydb->ocontexts[OCON_NODE];
2670 while (c) {
2671 if (c->u.node.addr == (addr & c->u.node.mask))
2672 break;
2673 c = c->next;
2674 }
2675 break;
2676 }
2677
2678 case AF_INET6:
2679 rc = -EINVAL;
2680 if (addrlen != sizeof(u64) * 2)
2681 goto out;
2682 c = policydb->ocontexts[OCON_NODE6];
2683 while (c) {
2684 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2685 c->u.node6.mask))
2686 break;
2687 c = c->next;
2688 }
2689 break;
2690
2691 default:
2692 rc = 0;
2693 *out_sid = SECINITSID_NODE;
2694 goto out;
2695 }
2696
2697 if (c) {
2698 if (!c->sid[0]) {
2699 rc = sidtab_context_to_sid(sidtab,
2700 &c->context[0],
2701 &c->sid[0]);
2702 if (rc == -ESTALE) {
2703 rcu_read_unlock();
2704 goto retry;
2705 }
2706 if (rc)
2707 goto out;
2708 }
2709 *out_sid = c->sid[0];
2710 } else {
2711 *out_sid = SECINITSID_NODE;
2712 }
2713
2714 rc = 0;
2715out:
2716 rcu_read_unlock();
2717 return rc;
2718}
2719
2720#define SIDS_NEL 25
2721
2722/**
2723 * security_get_user_sids - Obtain reachable SIDs for a user.
2724 * @state: SELinux state
2725 * @fromsid: starting SID
2726 * @username: username
2727 * @sids: array of reachable SIDs for user
2728 * @nel: number of elements in @sids
2729 *
2730 * Generate the set of SIDs for legal security contexts
2731 * for a given user that can be reached by @fromsid.
2732 * Set *@sids to point to a dynamically allocated
2733 * array containing the set of SIDs. Set *@nel to the
2734 * number of elements in the array.
2735 */
2736
2737int security_get_user_sids(struct selinux_state *state,
2738 u32 fromsid,
2739 char *username,
2740 u32 **sids,
2741 u32 *nel)
2742{
2743 struct selinux_policy *policy;
2744 struct policydb *policydb;
2745 struct sidtab *sidtab;
2746 struct context *fromcon, usercon;
2747 u32 *mysids = NULL, *mysids2, sid;
2748 u32 i, j, mynel, maxnel = SIDS_NEL;
2749 struct user_datum *user;
2750 struct role_datum *role;
2751 struct ebitmap_node *rnode, *tnode;
2752 int rc;
2753
2754 *sids = NULL;
2755 *nel = 0;
2756
2757 if (!selinux_initialized(state))
2758 return 0;
2759
2760 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_KERNEL);
2761 if (!mysids)
2762 return -ENOMEM;
2763
2764retry:
2765 mynel = 0;
2766 rcu_read_lock();
2767 policy = rcu_dereference(state->policy);
2768 policydb = &policy->policydb;
2769 sidtab = policy->sidtab;
2770
2771 context_init(&usercon);
2772
2773 rc = -EINVAL;
2774 fromcon = sidtab_search(sidtab, fromsid);
2775 if (!fromcon)
2776 goto out_unlock;
2777
2778 rc = -EINVAL;
2779 user = symtab_search(&policydb->p_users, username);
2780 if (!user)
2781 goto out_unlock;
2782
2783 usercon.user = user->value;
2784
2785 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2786 role = policydb->role_val_to_struct[i];
2787 usercon.role = i + 1;
2788 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2789 usercon.type = j + 1;
2790
2791 if (mls_setup_user_range(policydb, fromcon, user,
2792 &usercon))
2793 continue;
2794
2795 rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2796 if (rc == -ESTALE) {
2797 rcu_read_unlock();
2798 goto retry;
2799 }
2800 if (rc)
2801 goto out_unlock;
2802 if (mynel < maxnel) {
2803 mysids[mynel++] = sid;
2804 } else {
2805 rc = -ENOMEM;
2806 maxnel += SIDS_NEL;
2807 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2808 if (!mysids2)
2809 goto out_unlock;
2810 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2811 kfree(mysids);
2812 mysids = mysids2;
2813 mysids[mynel++] = sid;
2814 }
2815 }
2816 }
2817 rc = 0;
2818out_unlock:
2819 rcu_read_unlock();
2820 if (rc || !mynel) {
2821 kfree(mysids);
2822 return rc;
2823 }
2824
2825 rc = -ENOMEM;
2826 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2827 if (!mysids2) {
2828 kfree(mysids);
2829 return rc;
2830 }
2831 for (i = 0, j = 0; i < mynel; i++) {
2832 struct av_decision dummy_avd;
2833 rc = avc_has_perm_noaudit(state,
2834 fromsid, mysids[i],
2835 SECCLASS_PROCESS, /* kernel value */
2836 PROCESS__TRANSITION, AVC_STRICT,
2837 &dummy_avd);
2838 if (!rc)
2839 mysids2[j++] = mysids[i];
2840 cond_resched();
2841 }
2842 kfree(mysids);
2843 *sids = mysids2;
2844 *nel = j;
2845 return 0;
2846}
2847
2848/**
2849 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2850 * @fstype: filesystem type
2851 * @path: path from root of mount
2852 * @sclass: file security class
2853 * @sid: SID for path
2854 *
2855 * Obtain a SID to use for a file in a filesystem that
2856 * cannot support xattr or use a fixed labeling behavior like
2857 * transition SIDs or task SIDs.
2858 *
2859 * WARNING: This function may return -ESTALE, indicating that the caller
2860 * must retry the operation after re-acquiring the policy pointer!
2861 */
2862static inline int __security_genfs_sid(struct selinux_policy *policy,
2863 const char *fstype,
2864 char *path,
2865 u16 orig_sclass,
2866 u32 *sid)
2867{
2868 struct policydb *policydb = &policy->policydb;
2869 struct sidtab *sidtab = policy->sidtab;
2870 int len;
2871 u16 sclass;
2872 struct genfs *genfs;
2873 struct ocontext *c;
2874 int rc, cmp = 0;
2875
2876 while (path[0] == '/' && path[1] == '/')
2877 path++;
2878
2879 sclass = unmap_class(&policy->map, orig_sclass);
2880 *sid = SECINITSID_UNLABELED;
2881
2882 for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2883 cmp = strcmp(fstype, genfs->fstype);
2884 if (cmp <= 0)
2885 break;
2886 }
2887
2888 rc = -ENOENT;
2889 if (!genfs || cmp)
2890 goto out;
2891
2892 for (c = genfs->head; c; c = c->next) {
2893 len = strlen(c->u.name);
2894 if ((!c->v.sclass || sclass == c->v.sclass) &&
2895 (strncmp(c->u.name, path, len) == 0))
2896 break;
2897 }
2898
2899 rc = -ENOENT;
2900 if (!c)
2901 goto out;
2902
2903 if (!c->sid[0]) {
2904 rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]);
2905 if (rc)
2906 goto out;
2907 }
2908
2909 *sid = c->sid[0];
2910 rc = 0;
2911out:
2912 return rc;
2913}
2914
2915/**
2916 * security_genfs_sid - Obtain a SID for a file in a filesystem
2917 * @state: SELinux state
2918 * @fstype: filesystem type
2919 * @path: path from root of mount
2920 * @sclass: file security class
2921 * @sid: SID for path
2922 *
2923 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2924 * it afterward.
2925 */
2926int security_genfs_sid(struct selinux_state *state,
2927 const char *fstype,
2928 char *path,
2929 u16 orig_sclass,
2930 u32 *sid)
2931{
2932 struct selinux_policy *policy;
2933 int retval;
2934
2935 if (!selinux_initialized(state)) {
2936 *sid = SECINITSID_UNLABELED;
2937 return 0;
2938 }
2939
2940 do {
2941 rcu_read_lock();
2942 policy = rcu_dereference(state->policy);
2943 retval = __security_genfs_sid(policy, fstype, path,
2944 orig_sclass, sid);
2945 rcu_read_unlock();
2946 } while (retval == -ESTALE);
2947 return retval;
2948}
2949
2950int selinux_policy_genfs_sid(struct selinux_policy *policy,
2951 const char *fstype,
2952 char *path,
2953 u16 orig_sclass,
2954 u32 *sid)
2955{
2956 /* no lock required, policy is not yet accessible by other threads */
2957 return __security_genfs_sid(policy, fstype, path, orig_sclass, sid);
2958}
2959
2960/**
2961 * security_fs_use - Determine how to handle labeling for a filesystem.
2962 * @state: SELinux state
2963 * @sb: superblock in question
2964 */
2965int security_fs_use(struct selinux_state *state, struct super_block *sb)
2966{
2967 struct selinux_policy *policy;
2968 struct policydb *policydb;
2969 struct sidtab *sidtab;
2970 int rc;
2971 struct ocontext *c;
2972 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2973 const char *fstype = sb->s_type->name;
2974
2975 if (!selinux_initialized(state)) {
2976 sbsec->behavior = SECURITY_FS_USE_NONE;
2977 sbsec->sid = SECINITSID_UNLABELED;
2978 return 0;
2979 }
2980
2981retry:
2982 rc = 0;
2983 rcu_read_lock();
2984 policy = rcu_dereference(state->policy);
2985 policydb = &policy->policydb;
2986 sidtab = policy->sidtab;
2987
2988 c = policydb->ocontexts[OCON_FSUSE];
2989 while (c) {
2990 if (strcmp(fstype, c->u.name) == 0)
2991 break;
2992 c = c->next;
2993 }
2994
2995 if (c) {
2996 sbsec->behavior = c->v.behavior;
2997 if (!c->sid[0]) {
2998 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2999 &c->sid[0]);
3000 if (rc == -ESTALE) {
3001 rcu_read_unlock();
3002 goto retry;
3003 }
3004 if (rc)
3005 goto out;
3006 }
3007 sbsec->sid = c->sid[0];
3008 } else {
3009 rc = __security_genfs_sid(policy, fstype, "/",
3010 SECCLASS_DIR, &sbsec->sid);
3011 if (rc == -ESTALE) {
3012 rcu_read_unlock();
3013 goto retry;
3014 }
3015 if (rc) {
3016 sbsec->behavior = SECURITY_FS_USE_NONE;
3017 rc = 0;
3018 } else {
3019 sbsec->behavior = SECURITY_FS_USE_GENFS;
3020 }
3021 }
3022
3023out:
3024 rcu_read_unlock();
3025 return rc;
3026}
3027
3028int security_get_bools(struct selinux_policy *policy,
3029 u32 *len, char ***names, int **values)
3030{
3031 struct policydb *policydb;
3032 u32 i;
3033 int rc;
3034
3035 policydb = &policy->policydb;
3036
3037 *names = NULL;
3038 *values = NULL;
3039
3040 rc = 0;
3041 *len = policydb->p_bools.nprim;
3042 if (!*len)
3043 goto out;
3044
3045 rc = -ENOMEM;
3046 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
3047 if (!*names)
3048 goto err;
3049
3050 rc = -ENOMEM;
3051 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
3052 if (!*values)
3053 goto err;
3054
3055 for (i = 0; i < *len; i++) {
3056 (*values)[i] = policydb->bool_val_to_struct[i]->state;
3057
3058 rc = -ENOMEM;
3059 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
3060 GFP_ATOMIC);
3061 if (!(*names)[i])
3062 goto err;
3063 }
3064 rc = 0;
3065out:
3066 return rc;
3067err:
3068 if (*names) {
3069 for (i = 0; i < *len; i++)
3070 kfree((*names)[i]);
3071 kfree(*names);
3072 }
3073 kfree(*values);
3074 *len = 0;
3075 *names = NULL;
3076 *values = NULL;
3077 goto out;
3078}
3079
3080
3081int security_set_bools(struct selinux_state *state, u32 len, int *values)
3082{
3083 struct selinux_policy *newpolicy, *oldpolicy;
3084 int rc;
3085 u32 i, seqno = 0;
3086
3087 if (!selinux_initialized(state))
3088 return -EINVAL;
3089
3090 oldpolicy = rcu_dereference_protected(state->policy,
3091 lockdep_is_held(&state->policy_mutex));
3092
3093 /* Consistency check on number of booleans, should never fail */
3094 if (WARN_ON(len != oldpolicy->policydb.p_bools.nprim))
3095 return -EINVAL;
3096
3097 newpolicy = kmemdup(oldpolicy, sizeof(*newpolicy), GFP_KERNEL);
3098 if (!newpolicy)
3099 return -ENOMEM;
3100
3101 /*
3102 * Deep copy only the parts of the policydb that might be
3103 * modified as a result of changing booleans.
3104 */
3105 rc = cond_policydb_dup(&newpolicy->policydb, &oldpolicy->policydb);
3106 if (rc) {
3107 kfree(newpolicy);
3108 return -ENOMEM;
3109 }
3110
3111 /* Update the boolean states in the copy */
3112 for (i = 0; i < len; i++) {
3113 int new_state = !!values[i];
3114 int old_state = newpolicy->policydb.bool_val_to_struct[i]->state;
3115
3116 if (new_state != old_state) {
3117 audit_log(audit_context(), GFP_ATOMIC,
3118 AUDIT_MAC_CONFIG_CHANGE,
3119 "bool=%s val=%d old_val=%d auid=%u ses=%u",
3120 sym_name(&newpolicy->policydb, SYM_BOOLS, i),
3121 new_state,
3122 old_state,
3123 from_kuid(&init_user_ns, audit_get_loginuid(current)),
3124 audit_get_sessionid(current));
3125 newpolicy->policydb.bool_val_to_struct[i]->state = new_state;
3126 }
3127 }
3128
3129 /* Re-evaluate the conditional rules in the copy */
3130 evaluate_cond_nodes(&newpolicy->policydb);
3131
3132 /* Set latest granting seqno for new policy */
3133 newpolicy->latest_granting = oldpolicy->latest_granting + 1;
3134 seqno = newpolicy->latest_granting;
3135
3136 /* Install the new policy */
3137 rcu_assign_pointer(state->policy, newpolicy);
3138
3139 /*
3140 * Free the conditional portions of the old policydb
3141 * that were copied for the new policy, and the oldpolicy
3142 * structure itself but not what it references.
3143 */
3144 synchronize_rcu();
3145 selinux_policy_cond_free(oldpolicy);
3146
3147 /* Notify others of the policy change */
3148 selinux_notify_policy_change(state, seqno);
3149 return 0;
3150}
3151
3152int security_get_bool_value(struct selinux_state *state,
3153 u32 index)
3154{
3155 struct selinux_policy *policy;
3156 struct policydb *policydb;
3157 int rc;
3158 u32 len;
3159
3160 if (!selinux_initialized(state))
3161 return 0;
3162
3163 rcu_read_lock();
3164 policy = rcu_dereference(state->policy);
3165 policydb = &policy->policydb;
3166
3167 rc = -EFAULT;
3168 len = policydb->p_bools.nprim;
3169 if (index >= len)
3170 goto out;
3171
3172 rc = policydb->bool_val_to_struct[index]->state;
3173out:
3174 rcu_read_unlock();
3175 return rc;
3176}
3177
3178static int security_preserve_bools(struct selinux_policy *oldpolicy,
3179 struct selinux_policy *newpolicy)
3180{
3181 int rc, *bvalues = NULL;
3182 char **bnames = NULL;
3183 struct cond_bool_datum *booldatum;
3184 u32 i, nbools = 0;
3185
3186 rc = security_get_bools(oldpolicy, &nbools, &bnames, &bvalues);
3187 if (rc)
3188 goto out;
3189 for (i = 0; i < nbools; i++) {
3190 booldatum = symtab_search(&newpolicy->policydb.p_bools,
3191 bnames[i]);
3192 if (booldatum)
3193 booldatum->state = bvalues[i];
3194 }
3195 evaluate_cond_nodes(&newpolicy->policydb);
3196
3197out:
3198 if (bnames) {
3199 for (i = 0; i < nbools; i++)
3200 kfree(bnames[i]);
3201 }
3202 kfree(bnames);
3203 kfree(bvalues);
3204 return rc;
3205}
3206
3207/*
3208 * security_sid_mls_copy() - computes a new sid based on the given
3209 * sid and the mls portion of mls_sid.
3210 */
3211int security_sid_mls_copy(struct selinux_state *state,
3212 u32 sid, u32 mls_sid, u32 *new_sid)
3213{
3214 struct selinux_policy *policy;
3215 struct policydb *policydb;
3216 struct sidtab *sidtab;
3217 struct context *context1;
3218 struct context *context2;
3219 struct context newcon;
3220 char *s;
3221 u32 len;
3222 int rc;
3223
3224 if (!selinux_initialized(state)) {
3225 *new_sid = sid;
3226 return 0;
3227 }
3228
3229retry:
3230 rc = 0;
3231 context_init(&newcon);
3232
3233 rcu_read_lock();
3234 policy = rcu_dereference(state->policy);
3235 policydb = &policy->policydb;
3236 sidtab = policy->sidtab;
3237
3238 if (!policydb->mls_enabled) {
3239 *new_sid = sid;
3240 goto out_unlock;
3241 }
3242
3243 rc = -EINVAL;
3244 context1 = sidtab_search(sidtab, sid);
3245 if (!context1) {
3246 pr_err("SELinux: %s: unrecognized SID %d\n",
3247 __func__, sid);
3248 goto out_unlock;
3249 }
3250
3251 rc = -EINVAL;
3252 context2 = sidtab_search(sidtab, mls_sid);
3253 if (!context2) {
3254 pr_err("SELinux: %s: unrecognized SID %d\n",
3255 __func__, mls_sid);
3256 goto out_unlock;
3257 }
3258
3259 newcon.user = context1->user;
3260 newcon.role = context1->role;
3261 newcon.type = context1->type;
3262 rc = mls_context_cpy(&newcon, context2);
3263 if (rc)
3264 goto out_unlock;
3265
3266 /* Check the validity of the new context. */
3267 if (!policydb_context_isvalid(policydb, &newcon)) {
3268 rc = convert_context_handle_invalid_context(state, policydb,
3269 &newcon);
3270 if (rc) {
3271 if (!context_struct_to_string(policydb, &newcon, &s,
3272 &len)) {
3273 struct audit_buffer *ab;
3274
3275 ab = audit_log_start(audit_context(),
3276 GFP_ATOMIC,
3277 AUDIT_SELINUX_ERR);
3278 audit_log_format(ab,
3279 "op=security_sid_mls_copy invalid_context=");
3280 /* don't record NUL with untrusted strings */
3281 audit_log_n_untrustedstring(ab, s, len - 1);
3282 audit_log_end(ab);
3283 kfree(s);
3284 }
3285 goto out_unlock;
3286 }
3287 }
3288 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3289 if (rc == -ESTALE) {
3290 rcu_read_unlock();
3291 context_destroy(&newcon);
3292 goto retry;
3293 }
3294out_unlock:
3295 rcu_read_unlock();
3296 context_destroy(&newcon);
3297 return rc;
3298}
3299
3300/**
3301 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3302 * @state: SELinux state
3303 * @nlbl_sid: NetLabel SID
3304 * @nlbl_type: NetLabel labeling protocol type
3305 * @xfrm_sid: XFRM SID
3306 *
3307 * Description:
3308 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3309 * resolved into a single SID it is returned via @peer_sid and the function
3310 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3311 * returns a negative value. A table summarizing the behavior is below:
3312 *
3313 * | function return | @sid
3314 * ------------------------------+-----------------+-----------------
3315 * no peer labels | 0 | SECSID_NULL
3316 * single peer label | 0 | <peer_label>
3317 * multiple, consistent labels | 0 | <peer_label>
3318 * multiple, inconsistent labels | -<errno> | SECSID_NULL
3319 *
3320 */
3321int security_net_peersid_resolve(struct selinux_state *state,
3322 u32 nlbl_sid, u32 nlbl_type,
3323 u32 xfrm_sid,
3324 u32 *peer_sid)
3325{
3326 struct selinux_policy *policy;
3327 struct policydb *policydb;
3328 struct sidtab *sidtab;
3329 int rc;
3330 struct context *nlbl_ctx;
3331 struct context *xfrm_ctx;
3332
3333 *peer_sid = SECSID_NULL;
3334
3335 /* handle the common (which also happens to be the set of easy) cases
3336 * right away, these two if statements catch everything involving a
3337 * single or absent peer SID/label */
3338 if (xfrm_sid == SECSID_NULL) {
3339 *peer_sid = nlbl_sid;
3340 return 0;
3341 }
3342 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3343 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3344 * is present */
3345 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3346 *peer_sid = xfrm_sid;
3347 return 0;
3348 }
3349
3350 if (!selinux_initialized(state))
3351 return 0;
3352
3353 rcu_read_lock();
3354 policy = rcu_dereference(state->policy);
3355 policydb = &policy->policydb;
3356 sidtab = policy->sidtab;
3357
3358 /*
3359 * We don't need to check initialized here since the only way both
3360 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3361 * security server was initialized and state->initialized was true.
3362 */
3363 if (!policydb->mls_enabled) {
3364 rc = 0;
3365 goto out;
3366 }
3367
3368 rc = -EINVAL;
3369 nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3370 if (!nlbl_ctx) {
3371 pr_err("SELinux: %s: unrecognized SID %d\n",
3372 __func__, nlbl_sid);
3373 goto out;
3374 }
3375 rc = -EINVAL;
3376 xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3377 if (!xfrm_ctx) {
3378 pr_err("SELinux: %s: unrecognized SID %d\n",
3379 __func__, xfrm_sid);
3380 goto out;
3381 }
3382 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3383 if (rc)
3384 goto out;
3385
3386 /* at present NetLabel SIDs/labels really only carry MLS
3387 * information so if the MLS portion of the NetLabel SID
3388 * matches the MLS portion of the labeled XFRM SID/label
3389 * then pass along the XFRM SID as it is the most
3390 * expressive */
3391 *peer_sid = xfrm_sid;
3392out:
3393 rcu_read_unlock();
3394 return rc;
3395}
3396
3397static int get_classes_callback(void *k, void *d, void *args)
3398{
3399 struct class_datum *datum = d;
3400 char *name = k, **classes = args;
3401 int value = datum->value - 1;
3402
3403 classes[value] = kstrdup(name, GFP_ATOMIC);
3404 if (!classes[value])
3405 return -ENOMEM;
3406
3407 return 0;
3408}
3409
3410int security_get_classes(struct selinux_policy *policy,
3411 char ***classes, int *nclasses)
3412{
3413 struct policydb *policydb;
3414 int rc;
3415
3416 policydb = &policy->policydb;
3417
3418 rc = -ENOMEM;
3419 *nclasses = policydb->p_classes.nprim;
3420 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3421 if (!*classes)
3422 goto out;
3423
3424 rc = hashtab_map(&policydb->p_classes.table, get_classes_callback,
3425 *classes);
3426 if (rc) {
3427 int i;
3428 for (i = 0; i < *nclasses; i++)
3429 kfree((*classes)[i]);
3430 kfree(*classes);
3431 }
3432
3433out:
3434 return rc;
3435}
3436
3437static int get_permissions_callback(void *k, void *d, void *args)
3438{
3439 struct perm_datum *datum = d;
3440 char *name = k, **perms = args;
3441 int value = datum->value - 1;
3442
3443 perms[value] = kstrdup(name, GFP_ATOMIC);
3444 if (!perms[value])
3445 return -ENOMEM;
3446
3447 return 0;
3448}
3449
3450int security_get_permissions(struct selinux_policy *policy,
3451 char *class, char ***perms, int *nperms)
3452{
3453 struct policydb *policydb;
3454 int rc, i;
3455 struct class_datum *match;
3456
3457 policydb = &policy->policydb;
3458
3459 rc = -EINVAL;
3460 match = symtab_search(&policydb->p_classes, class);
3461 if (!match) {
3462 pr_err("SELinux: %s: unrecognized class %s\n",
3463 __func__, class);
3464 goto out;
3465 }
3466
3467 rc = -ENOMEM;
3468 *nperms = match->permissions.nprim;
3469 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3470 if (!*perms)
3471 goto out;
3472
3473 if (match->comdatum) {
3474 rc = hashtab_map(&match->comdatum->permissions.table,
3475 get_permissions_callback, *perms);
3476 if (rc)
3477 goto err;
3478 }
3479
3480 rc = hashtab_map(&match->permissions.table, get_permissions_callback,
3481 *perms);
3482 if (rc)
3483 goto err;
3484
3485out:
3486 return rc;
3487
3488err:
3489 for (i = 0; i < *nperms; i++)
3490 kfree((*perms)[i]);
3491 kfree(*perms);
3492 return rc;
3493}
3494
3495int security_get_reject_unknown(struct selinux_state *state)
3496{
3497 struct selinux_policy *policy;
3498 int value;
3499
3500 if (!selinux_initialized(state))
3501 return 0;
3502
3503 rcu_read_lock();
3504 policy = rcu_dereference(state->policy);
3505 value = policy->policydb.reject_unknown;
3506 rcu_read_unlock();
3507 return value;
3508}
3509
3510int security_get_allow_unknown(struct selinux_state *state)
3511{
3512 struct selinux_policy *policy;
3513 int value;
3514
3515 if (!selinux_initialized(state))
3516 return 0;
3517
3518 rcu_read_lock();
3519 policy = rcu_dereference(state->policy);
3520 value = policy->policydb.allow_unknown;
3521 rcu_read_unlock();
3522 return value;
3523}
3524
3525/**
3526 * security_policycap_supported - Check for a specific policy capability
3527 * @state: SELinux state
3528 * @req_cap: capability
3529 *
3530 * Description:
3531 * This function queries the currently loaded policy to see if it supports the
3532 * capability specified by @req_cap. Returns true (1) if the capability is
3533 * supported, false (0) if it isn't supported.
3534 *
3535 */
3536int security_policycap_supported(struct selinux_state *state,
3537 unsigned int req_cap)
3538{
3539 struct selinux_policy *policy;
3540 int rc;
3541
3542 if (!selinux_initialized(state))
3543 return 0;
3544
3545 rcu_read_lock();
3546 policy = rcu_dereference(state->policy);
3547 rc = ebitmap_get_bit(&policy->policydb.policycaps, req_cap);
3548 rcu_read_unlock();
3549
3550 return rc;
3551}
3552
3553struct selinux_audit_rule {
3554 u32 au_seqno;
3555 struct context au_ctxt;
3556};
3557
3558void selinux_audit_rule_free(void *vrule)
3559{
3560 struct selinux_audit_rule *rule = vrule;
3561
3562 if (rule) {
3563 context_destroy(&rule->au_ctxt);
3564 kfree(rule);
3565 }
3566}
3567
3568int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3569{
3570 struct selinux_state *state = &selinux_state;
3571 struct selinux_policy *policy;
3572 struct policydb *policydb;
3573 struct selinux_audit_rule *tmprule;
3574 struct role_datum *roledatum;
3575 struct type_datum *typedatum;
3576 struct user_datum *userdatum;
3577 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3578 int rc = 0;
3579
3580 *rule = NULL;
3581
3582 if (!selinux_initialized(state))
3583 return -EOPNOTSUPP;
3584
3585 switch (field) {
3586 case AUDIT_SUBJ_USER:
3587 case AUDIT_SUBJ_ROLE:
3588 case AUDIT_SUBJ_TYPE:
3589 case AUDIT_OBJ_USER:
3590 case AUDIT_OBJ_ROLE:
3591 case AUDIT_OBJ_TYPE:
3592 /* only 'equals' and 'not equals' fit user, role, and type */
3593 if (op != Audit_equal && op != Audit_not_equal)
3594 return -EINVAL;
3595 break;
3596 case AUDIT_SUBJ_SEN:
3597 case AUDIT_SUBJ_CLR:
3598 case AUDIT_OBJ_LEV_LOW:
3599 case AUDIT_OBJ_LEV_HIGH:
3600 /* we do not allow a range, indicated by the presence of '-' */
3601 if (strchr(rulestr, '-'))
3602 return -EINVAL;
3603 break;
3604 default:
3605 /* only the above fields are valid */
3606 return -EINVAL;
3607 }
3608
3609 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3610 if (!tmprule)
3611 return -ENOMEM;
3612
3613 context_init(&tmprule->au_ctxt);
3614
3615 rcu_read_lock();
3616 policy = rcu_dereference(state->policy);
3617 policydb = &policy->policydb;
3618
3619 tmprule->au_seqno = policy->latest_granting;
3620
3621 switch (field) {
3622 case AUDIT_SUBJ_USER:
3623 case AUDIT_OBJ_USER:
3624 rc = -EINVAL;
3625 userdatum = symtab_search(&policydb->p_users, rulestr);
3626 if (!userdatum)
3627 goto out;
3628 tmprule->au_ctxt.user = userdatum->value;
3629 break;
3630 case AUDIT_SUBJ_ROLE:
3631 case AUDIT_OBJ_ROLE:
3632 rc = -EINVAL;
3633 roledatum = symtab_search(&policydb->p_roles, rulestr);
3634 if (!roledatum)
3635 goto out;
3636 tmprule->au_ctxt.role = roledatum->value;
3637 break;
3638 case AUDIT_SUBJ_TYPE:
3639 case AUDIT_OBJ_TYPE:
3640 rc = -EINVAL;
3641 typedatum = symtab_search(&policydb->p_types, rulestr);
3642 if (!typedatum)
3643 goto out;
3644 tmprule->au_ctxt.type = typedatum->value;
3645 break;
3646 case AUDIT_SUBJ_SEN:
3647 case AUDIT_SUBJ_CLR:
3648 case AUDIT_OBJ_LEV_LOW:
3649 case AUDIT_OBJ_LEV_HIGH:
3650 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3651 GFP_ATOMIC);
3652 if (rc)
3653 goto out;
3654 break;
3655 }
3656 rc = 0;
3657out:
3658 rcu_read_unlock();
3659
3660 if (rc) {
3661 selinux_audit_rule_free(tmprule);
3662 tmprule = NULL;
3663 }
3664
3665 *rule = tmprule;
3666
3667 return rc;
3668}
3669
3670/* Check to see if the rule contains any selinux fields */
3671int selinux_audit_rule_known(struct audit_krule *rule)
3672{
3673 int i;
3674
3675 for (i = 0; i < rule->field_count; i++) {
3676 struct audit_field *f = &rule->fields[i];
3677 switch (f->type) {
3678 case AUDIT_SUBJ_USER:
3679 case AUDIT_SUBJ_ROLE:
3680 case AUDIT_SUBJ_TYPE:
3681 case AUDIT_SUBJ_SEN:
3682 case AUDIT_SUBJ_CLR:
3683 case AUDIT_OBJ_USER:
3684 case AUDIT_OBJ_ROLE:
3685 case AUDIT_OBJ_TYPE:
3686 case AUDIT_OBJ_LEV_LOW:
3687 case AUDIT_OBJ_LEV_HIGH:
3688 return 1;
3689 }
3690 }
3691
3692 return 0;
3693}
3694
3695int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule)
3696{
3697 struct selinux_state *state = &selinux_state;
3698 struct selinux_policy *policy;
3699 struct context *ctxt;
3700 struct mls_level *level;
3701 struct selinux_audit_rule *rule = vrule;
3702 int match = 0;
3703
3704 if (unlikely(!rule)) {
3705 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3706 return -ENOENT;
3707 }
3708
3709 if (!selinux_initialized(state))
3710 return 0;
3711
3712 rcu_read_lock();
3713
3714 policy = rcu_dereference(state->policy);
3715
3716 if (rule->au_seqno < policy->latest_granting) {
3717 match = -ESTALE;
3718 goto out;
3719 }
3720
3721 ctxt = sidtab_search(policy->sidtab, sid);
3722 if (unlikely(!ctxt)) {
3723 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3724 sid);
3725 match = -ENOENT;
3726 goto out;
3727 }
3728
3729 /* a field/op pair that is not caught here will simply fall through
3730 without a match */
3731 switch (field) {
3732 case AUDIT_SUBJ_USER:
3733 case AUDIT_OBJ_USER:
3734 switch (op) {
3735 case Audit_equal:
3736 match = (ctxt->user == rule->au_ctxt.user);
3737 break;
3738 case Audit_not_equal:
3739 match = (ctxt->user != rule->au_ctxt.user);
3740 break;
3741 }
3742 break;
3743 case AUDIT_SUBJ_ROLE:
3744 case AUDIT_OBJ_ROLE:
3745 switch (op) {
3746 case Audit_equal:
3747 match = (ctxt->role == rule->au_ctxt.role);
3748 break;
3749 case Audit_not_equal:
3750 match = (ctxt->role != rule->au_ctxt.role);
3751 break;
3752 }
3753 break;
3754 case AUDIT_SUBJ_TYPE:
3755 case AUDIT_OBJ_TYPE:
3756 switch (op) {
3757 case Audit_equal:
3758 match = (ctxt->type == rule->au_ctxt.type);
3759 break;
3760 case Audit_not_equal:
3761 match = (ctxt->type != rule->au_ctxt.type);
3762 break;
3763 }
3764 break;
3765 case AUDIT_SUBJ_SEN:
3766 case AUDIT_SUBJ_CLR:
3767 case AUDIT_OBJ_LEV_LOW:
3768 case AUDIT_OBJ_LEV_HIGH:
3769 level = ((field == AUDIT_SUBJ_SEN ||
3770 field == AUDIT_OBJ_LEV_LOW) ?
3771 &ctxt->range.level[0] : &ctxt->range.level[1]);
3772 switch (op) {
3773 case Audit_equal:
3774 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3775 level);
3776 break;
3777 case Audit_not_equal:
3778 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3779 level);
3780 break;
3781 case Audit_lt:
3782 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3783 level) &&
3784 !mls_level_eq(&rule->au_ctxt.range.level[0],
3785 level));
3786 break;
3787 case Audit_le:
3788 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3789 level);
3790 break;
3791 case Audit_gt:
3792 match = (mls_level_dom(level,
3793 &rule->au_ctxt.range.level[0]) &&
3794 !mls_level_eq(level,
3795 &rule->au_ctxt.range.level[0]));
3796 break;
3797 case Audit_ge:
3798 match = mls_level_dom(level,
3799 &rule->au_ctxt.range.level[0]);
3800 break;
3801 }
3802 }
3803
3804out:
3805 rcu_read_unlock();
3806 return match;
3807}
3808
3809static int aurule_avc_callback(u32 event)
3810{
3811 if (event == AVC_CALLBACK_RESET)
3812 return audit_update_lsm_rules();
3813 return 0;
3814}
3815
3816static int __init aurule_init(void)
3817{
3818 int err;
3819
3820 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3821 if (err)
3822 panic("avc_add_callback() failed, error %d\n", err);
3823
3824 return err;
3825}
3826__initcall(aurule_init);
3827
3828#ifdef CONFIG_NETLABEL
3829/**
3830 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3831 * @secattr: the NetLabel packet security attributes
3832 * @sid: the SELinux SID
3833 *
3834 * Description:
3835 * Attempt to cache the context in @ctx, which was derived from the packet in
3836 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3837 * already been initialized.
3838 *
3839 */
3840static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3841 u32 sid)
3842{
3843 u32 *sid_cache;
3844
3845 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3846 if (sid_cache == NULL)
3847 return;
3848 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3849 if (secattr->cache == NULL) {
3850 kfree(sid_cache);
3851 return;
3852 }
3853
3854 *sid_cache = sid;
3855 secattr->cache->free = kfree;
3856 secattr->cache->data = sid_cache;
3857 secattr->flags |= NETLBL_SECATTR_CACHE;
3858}
3859
3860/**
3861 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3862 * @state: SELinux state
3863 * @secattr: the NetLabel packet security attributes
3864 * @sid: the SELinux SID
3865 *
3866 * Description:
3867 * Convert the given NetLabel security attributes in @secattr into a
3868 * SELinux SID. If the @secattr field does not contain a full SELinux
3869 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3870 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3871 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3872 * conversion for future lookups. Returns zero on success, negative values on
3873 * failure.
3874 *
3875 */
3876int security_netlbl_secattr_to_sid(struct selinux_state *state,
3877 struct netlbl_lsm_secattr *secattr,
3878 u32 *sid)
3879{
3880 struct selinux_policy *policy;
3881 struct policydb *policydb;
3882 struct sidtab *sidtab;
3883 int rc;
3884 struct context *ctx;
3885 struct context ctx_new;
3886
3887 if (!selinux_initialized(state)) {
3888 *sid = SECSID_NULL;
3889 return 0;
3890 }
3891
3892retry:
3893 rc = 0;
3894 rcu_read_lock();
3895 policy = rcu_dereference(state->policy);
3896 policydb = &policy->policydb;
3897 sidtab = policy->sidtab;
3898
3899 if (secattr->flags & NETLBL_SECATTR_CACHE)
3900 *sid = *(u32 *)secattr->cache->data;
3901 else if (secattr->flags & NETLBL_SECATTR_SECID)
3902 *sid = secattr->attr.secid;
3903 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3904 rc = -EIDRM;
3905 ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3906 if (ctx == NULL)
3907 goto out;
3908
3909 context_init(&ctx_new);
3910 ctx_new.user = ctx->user;
3911 ctx_new.role = ctx->role;
3912 ctx_new.type = ctx->type;
3913 mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3914 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3915 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3916 if (rc)
3917 goto out;
3918 }
3919 rc = -EIDRM;
3920 if (!mls_context_isvalid(policydb, &ctx_new)) {
3921 ebitmap_destroy(&ctx_new.range.level[0].cat);
3922 goto out;
3923 }
3924
3925 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3926 ebitmap_destroy(&ctx_new.range.level[0].cat);
3927 if (rc == -ESTALE) {
3928 rcu_read_unlock();
3929 goto retry;
3930 }
3931 if (rc)
3932 goto out;
3933
3934 security_netlbl_cache_add(secattr, *sid);
3935 } else
3936 *sid = SECSID_NULL;
3937
3938out:
3939 rcu_read_unlock();
3940 return rc;
3941}
3942
3943/**
3944 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3945 * @state: SELinux state
3946 * @sid: the SELinux SID
3947 * @secattr: the NetLabel packet security attributes
3948 *
3949 * Description:
3950 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3951 * Returns zero on success, negative values on failure.
3952 *
3953 */
3954int security_netlbl_sid_to_secattr(struct selinux_state *state,
3955 u32 sid, struct netlbl_lsm_secattr *secattr)
3956{
3957 struct selinux_policy *policy;
3958 struct policydb *policydb;
3959 int rc;
3960 struct context *ctx;
3961
3962 if (!selinux_initialized(state))
3963 return 0;
3964
3965 rcu_read_lock();
3966 policy = rcu_dereference(state->policy);
3967 policydb = &policy->policydb;
3968
3969 rc = -ENOENT;
3970 ctx = sidtab_search(policy->sidtab, sid);
3971 if (ctx == NULL)
3972 goto out;
3973
3974 rc = -ENOMEM;
3975 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3976 GFP_ATOMIC);
3977 if (secattr->domain == NULL)
3978 goto out;
3979
3980 secattr->attr.secid = sid;
3981 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3982 mls_export_netlbl_lvl(policydb, ctx, secattr);
3983 rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3984out:
3985 rcu_read_unlock();
3986 return rc;
3987}
3988#endif /* CONFIG_NETLABEL */
3989
3990/**
3991 * __security_read_policy - read the policy.
3992 * @policy: SELinux policy
3993 * @data: binary policy data
3994 * @len: length of data in bytes
3995 *
3996 */
3997static int __security_read_policy(struct selinux_policy *policy,
3998 void *data, size_t *len)
3999{
4000 int rc;
4001 struct policy_file fp;
4002
4003 fp.data = data;
4004 fp.len = *len;
4005
4006 rc = policydb_write(&policy->policydb, &fp);
4007 if (rc)
4008 return rc;
4009
4010 *len = (unsigned long)fp.data - (unsigned long)data;
4011 return 0;
4012}
4013
4014/**
4015 * security_read_policy - read the policy.
4016 * @state: selinux_state
4017 * @data: binary policy data
4018 * @len: length of data in bytes
4019 *
4020 */
4021int security_read_policy(struct selinux_state *state,
4022 void **data, size_t *len)
4023{
4024 struct selinux_policy *policy;
4025
4026 policy = rcu_dereference_protected(
4027 state->policy, lockdep_is_held(&state->policy_mutex));
4028 if (!policy)
4029 return -EINVAL;
4030
4031 *len = policy->policydb.len;
4032 *data = vmalloc_user(*len);
4033 if (!*data)
4034 return -ENOMEM;
4035
4036 return __security_read_policy(policy, *data, len);
4037}
4038
4039/**
4040 * security_read_state_kernel - read the policy.
4041 * @state: selinux_state
4042 * @data: binary policy data
4043 * @len: length of data in bytes
4044 *
4045 * Allocates kernel memory for reading SELinux policy.
4046 * This function is for internal use only and should not
4047 * be used for returning data to user space.
4048 *
4049 * This function must be called with policy_mutex held.
4050 */
4051int security_read_state_kernel(struct selinux_state *state,
4052 void **data, size_t *len)
4053{
4054 struct selinux_policy *policy;
4055
4056 policy = rcu_dereference_protected(
4057 state->policy, lockdep_is_held(&state->policy_mutex));
4058 if (!policy)
4059 return -EINVAL;
4060
4061 *len = policy->policydb.len;
4062 *data = vmalloc(*len);
4063 if (!*data)
4064 return -ENOMEM;
4065
4066 return __security_read_policy(policy, *data, len);
4067}
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}