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clk: qcom: msm8916: Fix bimc gpu clock ops
[linux/fpc-iii.git] / security / selinux / ss / services.c
blob2f02fa67ec2e833eefb6f98f9d6190f4012679a1
1 /*
2 * Implementation of the security services.
3 *
4 * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
5 * James Morris <jmorris@redhat.com>
6 *
7 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
8 *
9 * Support for enhanced MLS infrastructure.
10 * Support for context based audit filters.
11 *
12 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
13 *
14 * Added conditional policy language extensions
15 *
16 * Updated: Hewlett-Packard <paul@paul-moore.com>
17 *
18 * Added support for NetLabel
19 * Added support for the policy capability bitmap
20 *
21 * Updated: Chad Sellers <csellers@tresys.com>
22 *
23 * Added validation of kernel classes and permissions
24 *
25 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
26 *
27 * Added support for bounds domain and audit messaged on masked permissions
28 *
29 * Updated: Guido Trentalancia <guido@trentalancia.com>
30 *
31 * Added support for runtime switching of the policy type
32 *
33 * Copyright (C) 2008, 2009 NEC Corporation
34 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
35 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
36 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
37 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
38 * This program is free software; you can redistribute it and/or modify
39 * it under the terms of the GNU General Public License as published by
40 * the Free Software Foundation, version 2.
41 */
42 #include <linux/kernel.h>
43 #include <linux/slab.h>
44 #include <linux/string.h>
45 #include <linux/spinlock.h>
46 #include <linux/rcupdate.h>
47 #include <linux/errno.h>
48 #include <linux/in.h>
49 #include <linux/sched.h>
50 #include <linux/audit.h>
51 #include <linux/mutex.h>
52 #include <linux/selinux.h>
53 #include <linux/flex_array.h>
54 #include <linux/vmalloc.h>
55 #include <net/netlabel.h>
56
57 #include "flask.h"
58 #include "avc.h"
59 #include "avc_ss.h"
60 #include "security.h"
61 #include "context.h"
62 #include "policydb.h"
63 #include "sidtab.h"
64 #include "services.h"
65 #include "conditional.h"
66 #include "mls.h"
67 #include "objsec.h"
68 #include "netlabel.h"
69 #include "xfrm.h"
70 #include "ebitmap.h"
71 #include "audit.h"
72
73 /* Policy capability names */
74 char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = {
75 "network_peer_controls",
76 "open_perms",
77 "extended_socket_class",
78 "always_check_network",
79 "cgroup_seclabel"
80 };
81
82 int selinux_policycap_netpeer;
83 int selinux_policycap_openperm;
84 int selinux_policycap_extsockclass;
85 int selinux_policycap_alwaysnetwork;
86 int selinux_policycap_cgroupseclabel;
87
88 static DEFINE_RWLOCK(policy_rwlock);
89
90 static struct sidtab sidtab;
91 struct policydb policydb;
92 int ss_initialized;
93
94 /*
95 * The largest sequence number that has been used when
96 * providing an access decision to the access vector cache.
97 * The sequence number only changes when a policy change
98 * occurs.
99 */
100 static u32 latest_granting;
101
102 /* Forward declaration. */
103 static int context_struct_to_string(struct context *context, char **scontext,
104 u32 *scontext_len);
105
106 static void context_struct_compute_av(struct context *scontext,
107 struct context *tcontext,
108 u16 tclass,
109 struct av_decision *avd,
110 struct extended_perms *xperms);
111
112 struct selinux_mapping {
113 u16 value; /* policy value */
114 unsigned num_perms;
115 u32 perms[sizeof(u32) * 8];
116 };
117
118 static struct selinux_mapping *current_mapping;
119 static u16 current_mapping_size;
120
121 static int selinux_set_mapping(struct policydb *pol,
122 struct security_class_mapping *map,
123 struct selinux_mapping **out_map_p,
124 u16 *out_map_size)
125 {
126 struct selinux_mapping *out_map = NULL;
127 size_t size = sizeof(struct selinux_mapping);
128 u16 i, j;
129 unsigned k;
130 bool print_unknown_handle = false;
131
132 /* Find number of classes in the input mapping */
133 if (!map)
134 return -EINVAL;
135 i = 0;
136 while (map[i].name)
137 i++;
138
139 /* Allocate space for the class records, plus one for class zero */
140 out_map = kcalloc(++i, size, GFP_ATOMIC);
141 if (!out_map)
142 return -ENOMEM;
143
144 /* Store the raw class and permission values */
145 j = 0;
146 while (map[j].name) {
147 struct security_class_mapping *p_in = map + (j++);
148 struct selinux_mapping *p_out = out_map + j;
149
150 /* An empty class string skips ahead */
151 if (!strcmp(p_in->name, "")) {
152 p_out->num_perms = 0;
153 continue;
154 }
155
156 p_out->value = string_to_security_class(pol, p_in->name);
157 if (!p_out->value) {
158 printk(KERN_INFO
159 "SELinux: Class %s not defined in policy.\n",
160 p_in->name);
161 if (pol->reject_unknown)
162 goto err;
163 p_out->num_perms = 0;
164 print_unknown_handle = true;
165 continue;
166 }
167
168 k = 0;
169 while (p_in->perms[k]) {
170 /* An empty permission string skips ahead */
171 if (!*p_in->perms[k]) {
172 k++;
173 continue;
174 }
175 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
176 p_in->perms[k]);
177 if (!p_out->perms[k]) {
178 printk(KERN_INFO
179 "SELinux: Permission %s in class %s not defined in policy.\n",
180 p_in->perms[k], p_in->name);
181 if (pol->reject_unknown)
182 goto err;
183 print_unknown_handle = true;
184 }
185
186 k++;
187 }
188 p_out->num_perms = k;
189 }
190
191 if (print_unknown_handle)
192 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
193 pol->allow_unknown ? "allowed" : "denied");
194
195 *out_map_p = out_map;
196 *out_map_size = i;
197 return 0;
198 err:
199 kfree(out_map);
200 return -EINVAL;
201 }
202
203 /*
204 * Get real, policy values from mapped values
205 */
206
207 static u16 unmap_class(u16 tclass)
208 {
209 if (tclass < current_mapping_size)
210 return current_mapping[tclass].value;
211
212 return tclass;
213 }
214
215 /*
216 * Get kernel value for class from its policy value
217 */
218 static u16 map_class(u16 pol_value)
219 {
220 u16 i;
221
222 for (i = 1; i < current_mapping_size; i++) {
223 if (current_mapping[i].value == pol_value)
224 return i;
225 }
226
227 return SECCLASS_NULL;
228 }
229
230 static void map_decision(u16 tclass, struct av_decision *avd,
231 int allow_unknown)
232 {
233 if (tclass < current_mapping_size) {
234 unsigned i, n = current_mapping[tclass].num_perms;
235 u32 result;
236
237 for (i = 0, result = 0; i < n; i++) {
238 if (avd->allowed & current_mapping[tclass].perms[i])
239 result |= 1<<i;
240 if (allow_unknown && !current_mapping[tclass].perms[i])
241 result |= 1<<i;
242 }
243 avd->allowed = result;
244
245 for (i = 0, result = 0; i < n; i++)
246 if (avd->auditallow & current_mapping[tclass].perms[i])
247 result |= 1<<i;
248 avd->auditallow = result;
249
250 for (i = 0, result = 0; i < n; i++) {
251 if (avd->auditdeny & current_mapping[tclass].perms[i])
252 result |= 1<<i;
253 if (!allow_unknown && !current_mapping[tclass].perms[i])
254 result |= 1<<i;
255 }
256 /*
257 * In case the kernel has a bug and requests a permission
258 * between num_perms and the maximum permission number, we
259 * should audit that denial
260 */
261 for (; i < (sizeof(u32)*8); i++)
262 result |= 1<<i;
263 avd->auditdeny = result;
264 }
265 }
266
267 int security_mls_enabled(void)
268 {
269 return policydb.mls_enabled;
270 }
271
272 /*
273 * Return the boolean value of a constraint expression
274 * when it is applied to the specified source and target
275 * security contexts.
276 *
277 * xcontext is a special beast... It is used by the validatetrans rules
278 * only. For these rules, scontext is the context before the transition,
279 * tcontext is the context after the transition, and xcontext is the context
280 * of the process performing the transition. All other callers of
281 * constraint_expr_eval should pass in NULL for xcontext.
282 */
283 static int constraint_expr_eval(struct context *scontext,
284 struct context *tcontext,
285 struct context *xcontext,
286 struct constraint_expr *cexpr)
287 {
288 u32 val1, val2;
289 struct context *c;
290 struct role_datum *r1, *r2;
291 struct mls_level *l1, *l2;
292 struct constraint_expr *e;
293 int s[CEXPR_MAXDEPTH];
294 int sp = -1;
295
296 for (e = cexpr; e; e = e->next) {
297 switch (e->expr_type) {
298 case CEXPR_NOT:
299 BUG_ON(sp < 0);
300 s[sp] = !s[sp];
301 break;
302 case CEXPR_AND:
303 BUG_ON(sp < 1);
304 sp--;
305 s[sp] &= s[sp + 1];
306 break;
307 case CEXPR_OR:
308 BUG_ON(sp < 1);
309 sp--;
310 s[sp] |= s[sp + 1];
311 break;
312 case CEXPR_ATTR:
313 if (sp == (CEXPR_MAXDEPTH - 1))
314 return 0;
315 switch (e->attr) {
316 case CEXPR_USER:
317 val1 = scontext->user;
318 val2 = tcontext->user;
319 break;
320 case CEXPR_TYPE:
321 val1 = scontext->type;
322 val2 = tcontext->type;
323 break;
324 case CEXPR_ROLE:
325 val1 = scontext->role;
326 val2 = tcontext->role;
327 r1 = policydb.role_val_to_struct[val1 - 1];
328 r2 = policydb.role_val_to_struct[val2 - 1];
329 switch (e->op) {
330 case CEXPR_DOM:
331 s[++sp] = ebitmap_get_bit(&r1->dominates,
332 val2 - 1);
333 continue;
334 case CEXPR_DOMBY:
335 s[++sp] = ebitmap_get_bit(&r2->dominates,
336 val1 - 1);
337 continue;
338 case CEXPR_INCOMP:
339 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
340 val2 - 1) &&
341 !ebitmap_get_bit(&r2->dominates,
342 val1 - 1));
343 continue;
344 default:
345 break;
346 }
347 break;
348 case CEXPR_L1L2:
349 l1 = &(scontext->range.level[0]);
350 l2 = &(tcontext->range.level[0]);
351 goto mls_ops;
352 case CEXPR_L1H2:
353 l1 = &(scontext->range.level[0]);
354 l2 = &(tcontext->range.level[1]);
355 goto mls_ops;
356 case CEXPR_H1L2:
357 l1 = &(scontext->range.level[1]);
358 l2 = &(tcontext->range.level[0]);
359 goto mls_ops;
360 case CEXPR_H1H2:
361 l1 = &(scontext->range.level[1]);
362 l2 = &(tcontext->range.level[1]);
363 goto mls_ops;
364 case CEXPR_L1H1:
365 l1 = &(scontext->range.level[0]);
366 l2 = &(scontext->range.level[1]);
367 goto mls_ops;
368 case CEXPR_L2H2:
369 l1 = &(tcontext->range.level[0]);
370 l2 = &(tcontext->range.level[1]);
371 goto mls_ops;
372 mls_ops:
373 switch (e->op) {
374 case CEXPR_EQ:
375 s[++sp] = mls_level_eq(l1, l2);
376 continue;
377 case CEXPR_NEQ:
378 s[++sp] = !mls_level_eq(l1, l2);
379 continue;
380 case CEXPR_DOM:
381 s[++sp] = mls_level_dom(l1, l2);
382 continue;
383 case CEXPR_DOMBY:
384 s[++sp] = mls_level_dom(l2, l1);
385 continue;
386 case CEXPR_INCOMP:
387 s[++sp] = mls_level_incomp(l2, l1);
388 continue;
389 default:
390 BUG();
391 return 0;
392 }
393 break;
394 default:
395 BUG();
396 return 0;
397 }
398
399 switch (e->op) {
400 case CEXPR_EQ:
401 s[++sp] = (val1 == val2);
402 break;
403 case CEXPR_NEQ:
404 s[++sp] = (val1 != val2);
405 break;
406 default:
407 BUG();
408 return 0;
409 }
410 break;
411 case CEXPR_NAMES:
412 if (sp == (CEXPR_MAXDEPTH-1))
413 return 0;
414 c = scontext;
415 if (e->attr & CEXPR_TARGET)
416 c = tcontext;
417 else if (e->attr & CEXPR_XTARGET) {
418 c = xcontext;
419 if (!c) {
420 BUG();
421 return 0;
422 }
423 }
424 if (e->attr & CEXPR_USER)
425 val1 = c->user;
426 else if (e->attr & CEXPR_ROLE)
427 val1 = c->role;
428 else if (e->attr & CEXPR_TYPE)
429 val1 = c->type;
430 else {
431 BUG();
432 return 0;
433 }
434
435 switch (e->op) {
436 case CEXPR_EQ:
437 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
438 break;
439 case CEXPR_NEQ:
440 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
441 break;
442 default:
443 BUG();
444 return 0;
445 }
446 break;
447 default:
448 BUG();
449 return 0;
450 }
451 }
452
453 BUG_ON(sp != 0);
454 return s[0];
455 }
456
457 /*
458 * security_dump_masked_av - dumps masked permissions during
459 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
460 */
461 static int dump_masked_av_helper(void *k, void *d, void *args)
462 {
463 struct perm_datum *pdatum = d;
464 char **permission_names = args;
465
466 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
467
468 permission_names[pdatum->value - 1] = (char *)k;
469
470 return 0;
471 }
472
473 static void security_dump_masked_av(struct context *scontext,
474 struct context *tcontext,
475 u16 tclass,
476 u32 permissions,
477 const char *reason)
478 {
479 struct common_datum *common_dat;
480 struct class_datum *tclass_dat;
481 struct audit_buffer *ab;
482 char *tclass_name;
483 char *scontext_name = NULL;
484 char *tcontext_name = NULL;
485 char *permission_names[32];
486 int index;
487 u32 length;
488 bool need_comma = false;
489
490 if (!permissions)
491 return;
492
493 tclass_name = sym_name(&policydb, SYM_CLASSES, tclass - 1);
494 tclass_dat = policydb.class_val_to_struct[tclass - 1];
495 common_dat = tclass_dat->comdatum;
496
497 /* init permission_names */
498 if (common_dat &&
499 hashtab_map(common_dat->permissions.table,
500 dump_masked_av_helper, permission_names) < 0)
501 goto out;
502
503 if (hashtab_map(tclass_dat->permissions.table,
504 dump_masked_av_helper, permission_names) < 0)
505 goto out;
506
507 /* get scontext/tcontext in text form */
508 if (context_struct_to_string(scontext,
509 &scontext_name, &length) < 0)
510 goto out;
511
512 if (context_struct_to_string(tcontext,
513 &tcontext_name, &length) < 0)
514 goto out;
515
516 /* audit a message */
517 ab = audit_log_start(current->audit_context,
518 GFP_ATOMIC, AUDIT_SELINUX_ERR);
519 if (!ab)
520 goto out;
521
522 audit_log_format(ab, "op=security_compute_av reason=%s "
523 "scontext=%s tcontext=%s tclass=%s perms=",
524 reason, scontext_name, tcontext_name, tclass_name);
525
526 for (index = 0; index < 32; index++) {
527 u32 mask = (1 << index);
528
529 if ((mask & permissions) == 0)
530 continue;
531
532 audit_log_format(ab, "%s%s",
533 need_comma ? "," : "",
534 permission_names[index]
535 ? permission_names[index] : "????");
536 need_comma = true;
537 }
538 audit_log_end(ab);
539 out:
540 /* release scontext/tcontext */
541 kfree(tcontext_name);
542 kfree(scontext_name);
543
544 return;
545 }
546
547 /*
548 * security_boundary_permission - drops violated permissions
549 * on boundary constraint.
550 */
551 static void type_attribute_bounds_av(struct context *scontext,
552 struct context *tcontext,
553 u16 tclass,
554 struct av_decision *avd)
555 {
556 struct context lo_scontext;
557 struct context lo_tcontext, *tcontextp = tcontext;
558 struct av_decision lo_avd;
559 struct type_datum *source;
560 struct type_datum *target;
561 u32 masked = 0;
562
563 source = flex_array_get_ptr(policydb.type_val_to_struct_array,
564 scontext->type - 1);
565 BUG_ON(!source);
566
567 if (!source->bounds)
568 return;
569
570 target = flex_array_get_ptr(policydb.type_val_to_struct_array,
571 tcontext->type - 1);
572 BUG_ON(!target);
573
574 memset(&lo_avd, 0, sizeof(lo_avd));
575
576 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
577 lo_scontext.type = source->bounds;
578
579 if (target->bounds) {
580 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
581 lo_tcontext.type = target->bounds;
582 tcontextp = &lo_tcontext;
583 }
584
585 context_struct_compute_av(&lo_scontext,
586 tcontextp,
587 tclass,
588 &lo_avd,
589 NULL);
590
591 masked = ~lo_avd.allowed & avd->allowed;
592
593 if (likely(!masked))
594 return; /* no masked permission */
595
596 /* mask violated permissions */
597 avd->allowed &= ~masked;
598
599 /* audit masked permissions */
600 security_dump_masked_av(scontext, tcontext,
601 tclass, masked, "bounds");
602 }
603
604 /*
605 * flag which drivers have permissions
606 * only looking for ioctl based extended permssions
607 */
608 void services_compute_xperms_drivers(
609 struct extended_perms *xperms,
610 struct avtab_node *node)
611 {
612 unsigned int i;
613
614 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
615 /* if one or more driver has all permissions allowed */
616 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
617 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
618 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
619 /* if allowing permissions within a driver */
620 security_xperm_set(xperms->drivers.p,
621 node->datum.u.xperms->driver);
622 }
623
624 /* If no ioctl commands are allowed, ignore auditallow and auditdeny */
625 if (node->key.specified & AVTAB_XPERMS_ALLOWED)
626 xperms->len = 1;
627 }
628
629 /*
630 * Compute access vectors and extended permissions based on a context
631 * structure pair for the permissions in a particular class.
632 */
633 static void context_struct_compute_av(struct context *scontext,
634 struct context *tcontext,
635 u16 tclass,
636 struct av_decision *avd,
637 struct extended_perms *xperms)
638 {
639 struct constraint_node *constraint;
640 struct role_allow *ra;
641 struct avtab_key avkey;
642 struct avtab_node *node;
643 struct class_datum *tclass_datum;
644 struct ebitmap *sattr, *tattr;
645 struct ebitmap_node *snode, *tnode;
646 unsigned int i, j;
647
648 avd->allowed = 0;
649 avd->auditallow = 0;
650 avd->auditdeny = 0xffffffff;
651 if (xperms) {
652 memset(&xperms->drivers, 0, sizeof(xperms->drivers));
653 xperms->len = 0;
654 }
655
656 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
657 if (printk_ratelimit())
658 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass);
659 return;
660 }
661
662 tclass_datum = policydb.class_val_to_struct[tclass - 1];
663
664 /*
665 * If a specific type enforcement rule was defined for
666 * this permission check, then use it.
667 */
668 avkey.target_class = tclass;
669 avkey.specified = AVTAB_AV | AVTAB_XPERMS;
670 sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1);
671 BUG_ON(!sattr);
672 tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1);
673 BUG_ON(!tattr);
674 ebitmap_for_each_positive_bit(sattr, snode, i) {
675 ebitmap_for_each_positive_bit(tattr, tnode, j) {
676 avkey.source_type = i + 1;
677 avkey.target_type = j + 1;
678 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
679 node;
680 node = avtab_search_node_next(node, avkey.specified)) {
681 if (node->key.specified == AVTAB_ALLOWED)
682 avd->allowed |= node->datum.u.data;
683 else if (node->key.specified == AVTAB_AUDITALLOW)
684 avd->auditallow |= node->datum.u.data;
685 else if (node->key.specified == AVTAB_AUDITDENY)
686 avd->auditdeny &= node->datum.u.data;
687 else if (xperms && (node->key.specified & AVTAB_XPERMS))
688 services_compute_xperms_drivers(xperms, node);
689 }
690
691 /* Check conditional av table for additional permissions */
692 cond_compute_av(&policydb.te_cond_avtab, &avkey,
693 avd, xperms);
694
695 }
696 }
697
698 /*
699 * Remove any permissions prohibited by a constraint (this includes
700 * the MLS policy).
701 */
702 constraint = tclass_datum->constraints;
703 while (constraint) {
704 if ((constraint->permissions & (avd->allowed)) &&
705 !constraint_expr_eval(scontext, tcontext, NULL,
706 constraint->expr)) {
707 avd->allowed &= ~(constraint->permissions);
708 }
709 constraint = constraint->next;
710 }
711
712 /*
713 * If checking process transition permission and the
714 * role is changing, then check the (current_role, new_role)
715 * pair.
716 */
717 if (tclass == policydb.process_class &&
718 (avd->allowed & policydb.process_trans_perms) &&
719 scontext->role != tcontext->role) {
720 for (ra = policydb.role_allow; ra; ra = ra->next) {
721 if (scontext->role == ra->role &&
722 tcontext->role == ra->new_role)
723 break;
724 }
725 if (!ra)
726 avd->allowed &= ~policydb.process_trans_perms;
727 }
728
729 /*
730 * If the given source and target types have boundary
731 * constraint, lazy checks have to mask any violated
732 * permission and notice it to userspace via audit.
733 */
734 type_attribute_bounds_av(scontext, tcontext,
735 tclass, avd);
736 }
737
738 static int security_validtrans_handle_fail(struct context *ocontext,
739 struct context *ncontext,
740 struct context *tcontext,
741 u16 tclass)
742 {
743 char *o = NULL, *n = NULL, *t = NULL;
744 u32 olen, nlen, tlen;
745
746 if (context_struct_to_string(ocontext, &o, &olen))
747 goto out;
748 if (context_struct_to_string(ncontext, &n, &nlen))
749 goto out;
750 if (context_struct_to_string(tcontext, &t, &tlen))
751 goto out;
752 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
753 "op=security_validate_transition seresult=denied"
754 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
755 o, n, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
756 out:
757 kfree(o);
758 kfree(n);
759 kfree(t);
760
761 if (!selinux_enforcing)
762 return 0;
763 return -EPERM;
764 }
765
766 static int security_compute_validatetrans(u32 oldsid, u32 newsid, u32 tasksid,
767 u16 orig_tclass, bool user)
768 {
769 struct context *ocontext;
770 struct context *ncontext;
771 struct context *tcontext;
772 struct class_datum *tclass_datum;
773 struct constraint_node *constraint;
774 u16 tclass;
775 int rc = 0;
776
777 if (!ss_initialized)
778 return 0;
779
780 read_lock(&policy_rwlock);
781
782 if (!user)
783 tclass = unmap_class(orig_tclass);
784 else
785 tclass = orig_tclass;
786
787 if (!tclass || tclass > policydb.p_classes.nprim) {
788 rc = -EINVAL;
789 goto out;
790 }
791 tclass_datum = policydb.class_val_to_struct[tclass - 1];
792
793 ocontext = sidtab_search(&sidtab, oldsid);
794 if (!ocontext) {
795 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
796 __func__, oldsid);
797 rc = -EINVAL;
798 goto out;
799 }
800
801 ncontext = sidtab_search(&sidtab, newsid);
802 if (!ncontext) {
803 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
804 __func__, newsid);
805 rc = -EINVAL;
806 goto out;
807 }
808
809 tcontext = sidtab_search(&sidtab, tasksid);
810 if (!tcontext) {
811 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
812 __func__, tasksid);
813 rc = -EINVAL;
814 goto out;
815 }
816
817 constraint = tclass_datum->validatetrans;
818 while (constraint) {
819 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
820 constraint->expr)) {
821 if (user)
822 rc = -EPERM;
823 else
824 rc = security_validtrans_handle_fail(ocontext,
825 ncontext,
826 tcontext,
827 tclass);
828 goto out;
829 }
830 constraint = constraint->next;
831 }
832
833 out:
834 read_unlock(&policy_rwlock);
835 return rc;
836 }
837
838 int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid,
839 u16 tclass)
840 {
841 return security_compute_validatetrans(oldsid, newsid, tasksid,
842 tclass, true);
843 }
844
845 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
846 u16 orig_tclass)
847 {
848 return security_compute_validatetrans(oldsid, newsid, tasksid,
849 orig_tclass, false);
850 }
851
852 /*
853 * security_bounded_transition - check whether the given
854 * transition is directed to bounded, or not.
855 * It returns 0, if @newsid is bounded by @oldsid.
856 * Otherwise, it returns error code.
857 *
858 * @oldsid : current security identifier
859 * @newsid : destinated security identifier
860 */
861 int security_bounded_transition(u32 old_sid, u32 new_sid)
862 {
863 struct context *old_context, *new_context;
864 struct type_datum *type;
865 int index;
866 int rc;
867
868 read_lock(&policy_rwlock);
869
870 rc = -EINVAL;
871 old_context = sidtab_search(&sidtab, old_sid);
872 if (!old_context) {
873 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
874 __func__, old_sid);
875 goto out;
876 }
877
878 rc = -EINVAL;
879 new_context = sidtab_search(&sidtab, new_sid);
880 if (!new_context) {
881 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
882 __func__, new_sid);
883 goto out;
884 }
885
886 rc = 0;
887 /* type/domain unchanged */
888 if (old_context->type == new_context->type)
889 goto out;
890
891 index = new_context->type;
892 while (true) {
893 type = flex_array_get_ptr(policydb.type_val_to_struct_array,
894 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(old_context,
916 &old_name, &length) &&
917 !context_struct_to_string(new_context,
918 &new_name, &length)) {
919 audit_log(current->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 }
929 out:
930 read_unlock(&policy_rwlock);
931
932 return rc;
933 }
934
935 static void avd_init(struct av_decision *avd)
936 {
937 avd->allowed = 0;
938 avd->auditallow = 0;
939 avd->auditdeny = 0xffffffff;
940 avd->seqno = latest_granting;
941 avd->flags = 0;
942 }
943
944 void 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
998 void security_compute_xperms_decision(u32 ssid,
999 u32 tsid,
1000 u16 orig_tclass,
1001 u8 driver,
1002 struct extended_perms_decision *xpermd)
1003 {
1004 u16 tclass;
1005 struct context *scontext, *tcontext;
1006 struct avtab_key avkey;
1007 struct avtab_node *node;
1008 struct ebitmap *sattr, *tattr;
1009 struct ebitmap_node *snode, *tnode;
1010 unsigned int i, j;
1011
1012 xpermd->driver = driver;
1013 xpermd->used = 0;
1014 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1015 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1016 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1017
1018 read_lock(&policy_rwlock);
1019 if (!ss_initialized)
1020 goto allow;
1021
1022 scontext = sidtab_search(&sidtab, ssid);
1023 if (!scontext) {
1024 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1025 __func__, ssid);
1026 goto out;
1027 }
1028
1029 tcontext = sidtab_search(&sidtab, tsid);
1030 if (!tcontext) {
1031 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1032 __func__, tsid);
1033 goto out;
1034 }
1035
1036 tclass = unmap_class(orig_tclass);
1037 if (unlikely(orig_tclass && !tclass)) {
1038 if (policydb.allow_unknown)
1039 goto allow;
1040 goto out;
1041 }
1042
1043
1044 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
1045 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1046 goto out;
1047 }
1048
1049 avkey.target_class = tclass;
1050 avkey.specified = AVTAB_XPERMS;
1051 sattr = flex_array_get(policydb.type_attr_map_array,
1052 scontext->type - 1);
1053 BUG_ON(!sattr);
1054 tattr = flex_array_get(policydb.type_attr_map_array,
1055 tcontext->type - 1);
1056 BUG_ON(!tattr);
1057 ebitmap_for_each_positive_bit(sattr, snode, i) {
1058 ebitmap_for_each_positive_bit(tattr, tnode, j) {
1059 avkey.source_type = i + 1;
1060 avkey.target_type = j + 1;
1061 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
1062 node;
1063 node = avtab_search_node_next(node, avkey.specified))
1064 services_compute_xperms_decision(xpermd, node);
1065
1066 cond_compute_xperms(&policydb.te_cond_avtab,
1067 &avkey, xpermd);
1068 }
1069 }
1070 out:
1071 read_unlock(&policy_rwlock);
1072 return;
1073 allow:
1074 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1075 goto out;
1076 }
1077
1078 /**
1079 * security_compute_av - Compute access vector decisions.
1080 * @ssid: source security identifier
1081 * @tsid: target security identifier
1082 * @tclass: target security class
1083 * @avd: access vector decisions
1084 * @xperms: extended permissions
1085 *
1086 * Compute a set of access vector decisions based on the
1087 * SID pair (@ssid, @tsid) for the permissions in @tclass.
1088 */
1089 void security_compute_av(u32 ssid,
1090 u32 tsid,
1091 u16 orig_tclass,
1092 struct av_decision *avd,
1093 struct extended_perms *xperms)
1094 {
1095 u16 tclass;
1096 struct context *scontext = NULL, *tcontext = NULL;
1097
1098 read_lock(&policy_rwlock);
1099 avd_init(avd);
1100 xperms->len = 0;
1101 if (!ss_initialized)
1102 goto allow;
1103
1104 scontext = sidtab_search(&sidtab, ssid);
1105 if (!scontext) {
1106 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1107 __func__, ssid);
1108 goto out;
1109 }
1110
1111 /* permissive domain? */
1112 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
1113 avd->flags |= AVD_FLAGS_PERMISSIVE;
1114
1115 tcontext = sidtab_search(&sidtab, tsid);
1116 if (!tcontext) {
1117 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1118 __func__, tsid);
1119 goto out;
1120 }
1121
1122 tclass = unmap_class(orig_tclass);
1123 if (unlikely(orig_tclass && !tclass)) {
1124 if (policydb.allow_unknown)
1125 goto allow;
1126 goto out;
1127 }
1128 context_struct_compute_av(scontext, tcontext, tclass, avd, xperms);
1129 map_decision(orig_tclass, avd, policydb.allow_unknown);
1130 out:
1131 read_unlock(&policy_rwlock);
1132 return;
1133 allow:
1134 avd->allowed = 0xffffffff;
1135 goto out;
1136 }
1137
1138 void security_compute_av_user(u32 ssid,
1139 u32 tsid,
1140 u16 tclass,
1141 struct av_decision *avd)
1142 {
1143 struct context *scontext = NULL, *tcontext = NULL;
1144
1145 read_lock(&policy_rwlock);
1146 avd_init(avd);
1147 if (!ss_initialized)
1148 goto allow;
1149
1150 scontext = sidtab_search(&sidtab, ssid);
1151 if (!scontext) {
1152 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1153 __func__, ssid);
1154 goto out;
1155 }
1156
1157 /* permissive domain? */
1158 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
1159 avd->flags |= AVD_FLAGS_PERMISSIVE;
1160
1161 tcontext = sidtab_search(&sidtab, tsid);
1162 if (!tcontext) {
1163 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1164 __func__, tsid);
1165 goto out;
1166 }
1167
1168 if (unlikely(!tclass)) {
1169 if (policydb.allow_unknown)
1170 goto allow;
1171 goto out;
1172 }
1173
1174 context_struct_compute_av(scontext, tcontext, tclass, avd, NULL);
1175 out:
1176 read_unlock(&policy_rwlock);
1177 return;
1178 allow:
1179 avd->allowed = 0xffffffff;
1180 goto out;
1181 }
1182
1183 /*
1184 * Write the security context string representation of
1185 * the context structure `context' into a dynamically
1186 * allocated string of the correct size. Set `*scontext'
1187 * to point to this string and set `*scontext_len' to
1188 * the length of the string.
1189 */
1190 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
1191 {
1192 char *scontextp;
1193
1194 if (scontext)
1195 *scontext = NULL;
1196 *scontext_len = 0;
1197
1198 if (context->len) {
1199 *scontext_len = context->len;
1200 if (scontext) {
1201 *scontext = kstrdup(context->str, GFP_ATOMIC);
1202 if (!(*scontext))
1203 return -ENOMEM;
1204 }
1205 return 0;
1206 }
1207
1208 /* Compute the size of the context. */
1209 *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1;
1210 *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1;
1211 *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1;
1212 *scontext_len += mls_compute_context_len(context);
1213
1214 if (!scontext)
1215 return 0;
1216
1217 /* Allocate space for the context; caller must free this space. */
1218 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1219 if (!scontextp)
1220 return -ENOMEM;
1221 *scontext = scontextp;
1222
1223 /*
1224 * Copy the user name, role name and type name into the context.
1225 */
1226 scontextp += sprintf(scontextp, "%s:%s:%s",
1227 sym_name(&policydb, SYM_USERS, context->user - 1),
1228 sym_name(&policydb, SYM_ROLES, context->role - 1),
1229 sym_name(&policydb, SYM_TYPES, context->type - 1));
1230
1231 mls_sid_to_context(context, &scontextp);
1232
1233 *scontextp = 0;
1234
1235 return 0;
1236 }
1237
1238 #include "initial_sid_to_string.h"
1239
1240 const char *security_get_initial_sid_context(u32 sid)
1241 {
1242 if (unlikely(sid > SECINITSID_NUM))
1243 return NULL;
1244 return initial_sid_to_string[sid];
1245 }
1246
1247 static int security_sid_to_context_core(u32 sid, char **scontext,
1248 u32 *scontext_len, int force)
1249 {
1250 struct context *context;
1251 int rc = 0;
1252
1253 if (scontext)
1254 *scontext = NULL;
1255 *scontext_len = 0;
1256
1257 if (!ss_initialized) {
1258 if (sid <= SECINITSID_NUM) {
1259 char *scontextp;
1260
1261 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1262 if (!scontext)
1263 goto out;
1264 scontextp = kmemdup(initial_sid_to_string[sid],
1265 *scontext_len, GFP_ATOMIC);
1266 if (!scontextp) {
1267 rc = -ENOMEM;
1268 goto out;
1269 }
1270 *scontext = scontextp;
1271 goto out;
1272 }
1273 printk(KERN_ERR "SELinux: %s: called before initial "
1274 "load_policy on unknown SID %d\n", __func__, sid);
1275 rc = -EINVAL;
1276 goto out;
1277 }
1278 read_lock(&policy_rwlock);
1279 if (force)
1280 context = sidtab_search_force(&sidtab, sid);
1281 else
1282 context = sidtab_search(&sidtab, sid);
1283 if (!context) {
1284 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1285 __func__, sid);
1286 rc = -EINVAL;
1287 goto out_unlock;
1288 }
1289 rc = context_struct_to_string(context, scontext, scontext_len);
1290 out_unlock:
1291 read_unlock(&policy_rwlock);
1292 out:
1293 return rc;
1294
1295 }
1296
1297 /**
1298 * security_sid_to_context - Obtain a context for a given SID.
1299 * @sid: security identifier, SID
1300 * @scontext: security context
1301 * @scontext_len: length in bytes
1302 *
1303 * Write the string representation of the context associated with @sid
1304 * into a dynamically allocated string of the correct size. Set @scontext
1305 * to point to this string and set @scontext_len to the length of the string.
1306 */
1307 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1308 {
1309 return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1310 }
1311
1312 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1313 {
1314 return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1315 }
1316
1317 /*
1318 * Caveat: Mutates scontext.
1319 */
1320 static int string_to_context_struct(struct policydb *pol,
1321 struct sidtab *sidtabp,
1322 char *scontext,
1323 u32 scontext_len,
1324 struct context *ctx,
1325 u32 def_sid)
1326 {
1327 struct role_datum *role;
1328 struct type_datum *typdatum;
1329 struct user_datum *usrdatum;
1330 char *scontextp, *p, oldc;
1331 int rc = 0;
1332
1333 context_init(ctx);
1334
1335 /* Parse the security context. */
1336
1337 rc = -EINVAL;
1338 scontextp = (char *) scontext;
1339
1340 /* Extract the user. */
1341 p = scontextp;
1342 while (*p && *p != ':')
1343 p++;
1344
1345 if (*p == 0)
1346 goto out;
1347
1348 *p++ = 0;
1349
1350 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1351 if (!usrdatum)
1352 goto out;
1353
1354 ctx->user = usrdatum->value;
1355
1356 /* Extract role. */
1357 scontextp = p;
1358 while (*p && *p != ':')
1359 p++;
1360
1361 if (*p == 0)
1362 goto out;
1363
1364 *p++ = 0;
1365
1366 role = hashtab_search(pol->p_roles.table, scontextp);
1367 if (!role)
1368 goto out;
1369 ctx->role = role->value;
1370
1371 /* Extract type. */
1372 scontextp = p;
1373 while (*p && *p != ':')
1374 p++;
1375 oldc = *p;
1376 *p++ = 0;
1377
1378 typdatum = hashtab_search(pol->p_types.table, scontextp);
1379 if (!typdatum || typdatum->attribute)
1380 goto out;
1381
1382 ctx->type = typdatum->value;
1383
1384 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1385 if (rc)
1386 goto out;
1387
1388 rc = -EINVAL;
1389 if ((p - scontext) < scontext_len)
1390 goto out;
1391
1392 /* Check the validity of the new context. */
1393 if (!policydb_context_isvalid(pol, ctx))
1394 goto out;
1395 rc = 0;
1396 out:
1397 if (rc)
1398 context_destroy(ctx);
1399 return rc;
1400 }
1401
1402 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1403 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1404 int force)
1405 {
1406 char *scontext2, *str = NULL;
1407 struct context context;
1408 int rc = 0;
1409
1410 /* An empty security context is never valid. */
1411 if (!scontext_len)
1412 return -EINVAL;
1413
1414 if (!ss_initialized) {
1415 int i;
1416
1417 for (i = 1; i < SECINITSID_NUM; i++) {
1418 if (!strcmp(initial_sid_to_string[i], scontext)) {
1419 *sid = i;
1420 return 0;
1421 }
1422 }
1423 *sid = SECINITSID_KERNEL;
1424 return 0;
1425 }
1426 *sid = SECSID_NULL;
1427
1428 /* Copy the string so that we can modify the copy as we parse it. */
1429 scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1430 if (!scontext2)
1431 return -ENOMEM;
1432 memcpy(scontext2, scontext, scontext_len);
1433 scontext2[scontext_len] = 0;
1434
1435 if (force) {
1436 /* Save another copy for storing in uninterpreted form */
1437 rc = -ENOMEM;
1438 str = kstrdup(scontext2, gfp_flags);
1439 if (!str)
1440 goto out;
1441 }
1442
1443 read_lock(&policy_rwlock);
1444 rc = string_to_context_struct(&policydb, &sidtab, scontext2,
1445 scontext_len, &context, def_sid);
1446 if (rc == -EINVAL && force) {
1447 context.str = str;
1448 context.len = scontext_len;
1449 str = NULL;
1450 } else if (rc)
1451 goto out_unlock;
1452 rc = sidtab_context_to_sid(&sidtab, &context, sid);
1453 context_destroy(&context);
1454 out_unlock:
1455 read_unlock(&policy_rwlock);
1456 out:
1457 kfree(scontext2);
1458 kfree(str);
1459 return rc;
1460 }
1461
1462 /**
1463 * security_context_to_sid - Obtain a SID for a given security context.
1464 * @scontext: security context
1465 * @scontext_len: length in bytes
1466 * @sid: security identifier, SID
1467 * @gfp: context for the allocation
1468 *
1469 * Obtains a SID associated with the security context that
1470 * has the string representation specified by @scontext.
1471 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1472 * memory is available, or 0 on success.
1473 */
1474 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid,
1475 gfp_t gfp)
1476 {
1477 return security_context_to_sid_core(scontext, scontext_len,
1478 sid, SECSID_NULL, gfp, 0);
1479 }
1480
1481 int security_context_str_to_sid(const char *scontext, u32 *sid, gfp_t gfp)
1482 {
1483 return security_context_to_sid(scontext, strlen(scontext), sid, gfp);
1484 }
1485
1486 /**
1487 * security_context_to_sid_default - Obtain a SID for a given security context,
1488 * falling back to specified default if needed.
1489 *
1490 * @scontext: security context
1491 * @scontext_len: length in bytes
1492 * @sid: security identifier, SID
1493 * @def_sid: default SID to assign on error
1494 *
1495 * Obtains a SID associated with the security context that
1496 * has the string representation specified by @scontext.
1497 * The default SID is passed to the MLS layer to be used to allow
1498 * kernel labeling of the MLS field if the MLS field is not present
1499 * (for upgrading to MLS without full relabel).
1500 * Implicitly forces adding of the context even if it cannot be mapped yet.
1501 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1502 * memory is available, or 0 on success.
1503 */
1504 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1505 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1506 {
1507 return security_context_to_sid_core(scontext, scontext_len,
1508 sid, def_sid, gfp_flags, 1);
1509 }
1510
1511 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1512 u32 *sid)
1513 {
1514 return security_context_to_sid_core(scontext, scontext_len,
1515 sid, SECSID_NULL, GFP_KERNEL, 1);
1516 }
1517
1518 static int compute_sid_handle_invalid_context(
1519 struct context *scontext,
1520 struct context *tcontext,
1521 u16 tclass,
1522 struct context *newcontext)
1523 {
1524 char *s = NULL, *t = NULL, *n = NULL;
1525 u32 slen, tlen, nlen;
1526
1527 if (context_struct_to_string(scontext, &s, &slen))
1528 goto out;
1529 if (context_struct_to_string(tcontext, &t, &tlen))
1530 goto out;
1531 if (context_struct_to_string(newcontext, &n, &nlen))
1532 goto out;
1533 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1534 "op=security_compute_sid invalid_context=%s"
1535 " scontext=%s"
1536 " tcontext=%s"
1537 " tclass=%s",
1538 n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
1539 out:
1540 kfree(s);
1541 kfree(t);
1542 kfree(n);
1543 if (!selinux_enforcing)
1544 return 0;
1545 return -EACCES;
1546 }
1547
1548 static void filename_compute_type(struct policydb *p, struct context *newcontext,
1549 u32 stype, u32 ttype, u16 tclass,
1550 const char *objname)
1551 {
1552 struct filename_trans ft;
1553 struct filename_trans_datum *otype;
1554
1555 /*
1556 * Most filename trans rules are going to live in specific directories
1557 * like /dev or /var/run. This bitmap will quickly skip rule searches
1558 * if the ttype does not contain any rules.
1559 */
1560 if (!ebitmap_get_bit(&p->filename_trans_ttypes, ttype))
1561 return;
1562
1563 ft.stype = stype;
1564 ft.ttype = ttype;
1565 ft.tclass = tclass;
1566 ft.name = objname;
1567
1568 otype = hashtab_search(p->filename_trans, &ft);
1569 if (otype)
1570 newcontext->type = otype->otype;
1571 }
1572
1573 static int security_compute_sid(u32 ssid,
1574 u32 tsid,
1575 u16 orig_tclass,
1576 u32 specified,
1577 const char *objname,
1578 u32 *out_sid,
1579 bool kern)
1580 {
1581 struct class_datum *cladatum = NULL;
1582 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1583 struct role_trans *roletr = NULL;
1584 struct avtab_key avkey;
1585 struct avtab_datum *avdatum;
1586 struct avtab_node *node;
1587 u16 tclass;
1588 int rc = 0;
1589 bool sock;
1590
1591 if (!ss_initialized) {
1592 switch (orig_tclass) {
1593 case SECCLASS_PROCESS: /* kernel value */
1594 *out_sid = ssid;
1595 break;
1596 default:
1597 *out_sid = tsid;
1598 break;
1599 }
1600 goto out;
1601 }
1602
1603 context_init(&newcontext);
1604
1605 read_lock(&policy_rwlock);
1606
1607 if (kern) {
1608 tclass = unmap_class(orig_tclass);
1609 sock = security_is_socket_class(orig_tclass);
1610 } else {
1611 tclass = orig_tclass;
1612 sock = security_is_socket_class(map_class(tclass));
1613 }
1614
1615 scontext = sidtab_search(&sidtab, ssid);
1616 if (!scontext) {
1617 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1618 __func__, ssid);
1619 rc = -EINVAL;
1620 goto out_unlock;
1621 }
1622 tcontext = sidtab_search(&sidtab, tsid);
1623 if (!tcontext) {
1624 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1625 __func__, tsid);
1626 rc = -EINVAL;
1627 goto out_unlock;
1628 }
1629
1630 if (tclass && tclass <= policydb.p_classes.nprim)
1631 cladatum = policydb.class_val_to_struct[tclass - 1];
1632
1633 /* Set the user identity. */
1634 switch (specified) {
1635 case AVTAB_TRANSITION:
1636 case AVTAB_CHANGE:
1637 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1638 newcontext.user = tcontext->user;
1639 } else {
1640 /* notice this gets both DEFAULT_SOURCE and unset */
1641 /* Use the process user identity. */
1642 newcontext.user = scontext->user;
1643 }
1644 break;
1645 case AVTAB_MEMBER:
1646 /* Use the related object owner. */
1647 newcontext.user = tcontext->user;
1648 break;
1649 }
1650
1651 /* Set the role to default values. */
1652 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1653 newcontext.role = scontext->role;
1654 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1655 newcontext.role = tcontext->role;
1656 } else {
1657 if ((tclass == policydb.process_class) || (sock == true))
1658 newcontext.role = scontext->role;
1659 else
1660 newcontext.role = OBJECT_R_VAL;
1661 }
1662
1663 /* Set the type to default values. */
1664 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1665 newcontext.type = scontext->type;
1666 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1667 newcontext.type = tcontext->type;
1668 } else {
1669 if ((tclass == policydb.process_class) || (sock == true)) {
1670 /* Use the type of process. */
1671 newcontext.type = scontext->type;
1672 } else {
1673 /* Use the type of the related object. */
1674 newcontext.type = tcontext->type;
1675 }
1676 }
1677
1678 /* Look for a type transition/member/change rule. */
1679 avkey.source_type = scontext->type;
1680 avkey.target_type = tcontext->type;
1681 avkey.target_class = tclass;
1682 avkey.specified = specified;
1683 avdatum = avtab_search(&policydb.te_avtab, &avkey);
1684
1685 /* If no permanent rule, also check for enabled conditional rules */
1686 if (!avdatum) {
1687 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1688 for (; node; node = avtab_search_node_next(node, specified)) {
1689 if (node->key.specified & AVTAB_ENABLED) {
1690 avdatum = &node->datum;
1691 break;
1692 }
1693 }
1694 }
1695
1696 if (avdatum) {
1697 /* Use the type from the type transition/member/change rule. */
1698 newcontext.type = avdatum->u.data;
1699 }
1700
1701 /* if we have a objname this is a file trans check so check those rules */
1702 if (objname)
1703 filename_compute_type(&policydb, &newcontext, scontext->type,
1704 tcontext->type, tclass, objname);
1705
1706 /* Check for class-specific changes. */
1707 if (specified & AVTAB_TRANSITION) {
1708 /* Look for a role transition rule. */
1709 for (roletr = policydb.role_tr; roletr; roletr = roletr->next) {
1710 if ((roletr->role == scontext->role) &&
1711 (roletr->type == tcontext->type) &&
1712 (roletr->tclass == tclass)) {
1713 /* Use the role transition rule. */
1714 newcontext.role = roletr->new_role;
1715 break;
1716 }
1717 }
1718 }
1719
1720 /* Set the MLS attributes.
1721 This is done last because it may allocate memory. */
1722 rc = mls_compute_sid(scontext, tcontext, tclass, specified,
1723 &newcontext, sock);
1724 if (rc)
1725 goto out_unlock;
1726
1727 /* Check the validity of the context. */
1728 if (!policydb_context_isvalid(&policydb, &newcontext)) {
1729 rc = compute_sid_handle_invalid_context(scontext,
1730 tcontext,
1731 tclass,
1732 &newcontext);
1733 if (rc)
1734 goto out_unlock;
1735 }
1736 /* Obtain the sid for the context. */
1737 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1738 out_unlock:
1739 read_unlock(&policy_rwlock);
1740 context_destroy(&newcontext);
1741 out:
1742 return rc;
1743 }
1744
1745 /**
1746 * security_transition_sid - Compute the SID for a new subject/object.
1747 * @ssid: source security identifier
1748 * @tsid: target security identifier
1749 * @tclass: target security class
1750 * @out_sid: security identifier for new subject/object
1751 *
1752 * Compute a SID to use for labeling a new subject or object in the
1753 * class @tclass based on a SID pair (@ssid, @tsid).
1754 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1755 * if insufficient memory is available, or %0 if the new SID was
1756 * computed successfully.
1757 */
1758 int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1759 const struct qstr *qstr, u32 *out_sid)
1760 {
1761 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1762 qstr ? qstr->name : NULL, out_sid, true);
1763 }
1764
1765 int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1766 const char *objname, u32 *out_sid)
1767 {
1768 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1769 objname, out_sid, false);
1770 }
1771
1772 /**
1773 * security_member_sid - Compute the SID for member selection.
1774 * @ssid: source security identifier
1775 * @tsid: target security identifier
1776 * @tclass: target security class
1777 * @out_sid: security identifier for selected member
1778 *
1779 * Compute a SID to use when selecting a member of a polyinstantiated
1780 * object of class @tclass based on a SID pair (@ssid, @tsid).
1781 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1782 * if insufficient memory is available, or %0 if the SID was
1783 * computed successfully.
1784 */
1785 int security_member_sid(u32 ssid,
1786 u32 tsid,
1787 u16 tclass,
1788 u32 *out_sid)
1789 {
1790 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL,
1791 out_sid, false);
1792 }
1793
1794 /**
1795 * security_change_sid - Compute the SID for object relabeling.
1796 * @ssid: source security identifier
1797 * @tsid: target security identifier
1798 * @tclass: target security class
1799 * @out_sid: security identifier for selected member
1800 *
1801 * Compute a SID to use for relabeling an object of class @tclass
1802 * based on a SID pair (@ssid, @tsid).
1803 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1804 * if insufficient memory is available, or %0 if the SID was
1805 * computed successfully.
1806 */
1807 int security_change_sid(u32 ssid,
1808 u32 tsid,
1809 u16 tclass,
1810 u32 *out_sid)
1811 {
1812 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1813 out_sid, false);
1814 }
1815
1816 /* Clone the SID into the new SID table. */
1817 static int clone_sid(u32 sid,
1818 struct context *context,
1819 void *arg)
1820 {
1821 struct sidtab *s = arg;
1822
1823 if (sid > SECINITSID_NUM)
1824 return sidtab_insert(s, sid, context);
1825 else
1826 return 0;
1827 }
1828
1829 static inline int convert_context_handle_invalid_context(struct context *context)
1830 {
1831 char *s;
1832 u32 len;
1833
1834 if (selinux_enforcing)
1835 return -EINVAL;
1836
1837 if (!context_struct_to_string(context, &s, &len)) {
1838 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s);
1839 kfree(s);
1840 }
1841 return 0;
1842 }
1843
1844 struct convert_context_args {
1845 struct policydb *oldp;
1846 struct policydb *newp;
1847 };
1848
1849 /*
1850 * Convert the values in the security context
1851 * structure `c' from the values specified
1852 * in the policy `p->oldp' to the values specified
1853 * in the policy `p->newp'. Verify that the
1854 * context is valid under the new policy.
1855 */
1856 static int convert_context(u32 key,
1857 struct context *c,
1858 void *p)
1859 {
1860 struct convert_context_args *args;
1861 struct context oldc;
1862 struct ocontext *oc;
1863 struct mls_range *range;
1864 struct role_datum *role;
1865 struct type_datum *typdatum;
1866 struct user_datum *usrdatum;
1867 char *s;
1868 u32 len;
1869 int rc = 0;
1870
1871 if (key <= SECINITSID_NUM)
1872 goto out;
1873
1874 args = p;
1875
1876 if (c->str) {
1877 struct context ctx;
1878
1879 rc = -ENOMEM;
1880 s = kstrdup(c->str, GFP_KERNEL);
1881 if (!s)
1882 goto out;
1883
1884 rc = string_to_context_struct(args->newp, NULL, s,
1885 c->len, &ctx, SECSID_NULL);
1886 kfree(s);
1887 if (!rc) {
1888 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n",
1889 c->str);
1890 /* Replace string with mapped representation. */
1891 kfree(c->str);
1892 memcpy(c, &ctx, sizeof(*c));
1893 goto out;
1894 } else if (rc == -EINVAL) {
1895 /* Retain string representation for later mapping. */
1896 rc = 0;
1897 goto out;
1898 } else {
1899 /* Other error condition, e.g. ENOMEM. */
1900 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n",
1901 c->str, -rc);
1902 goto out;
1903 }
1904 }
1905
1906 rc = context_cpy(&oldc, c);
1907 if (rc)
1908 goto out;
1909
1910 /* Convert the user. */
1911 rc = -EINVAL;
1912 usrdatum = hashtab_search(args->newp->p_users.table,
1913 sym_name(args->oldp, SYM_USERS, c->user - 1));
1914 if (!usrdatum)
1915 goto bad;
1916 c->user = usrdatum->value;
1917
1918 /* Convert the role. */
1919 rc = -EINVAL;
1920 role = hashtab_search(args->newp->p_roles.table,
1921 sym_name(args->oldp, SYM_ROLES, c->role - 1));
1922 if (!role)
1923 goto bad;
1924 c->role = role->value;
1925
1926 /* Convert the type. */
1927 rc = -EINVAL;
1928 typdatum = hashtab_search(args->newp->p_types.table,
1929 sym_name(args->oldp, SYM_TYPES, c->type - 1));
1930 if (!typdatum)
1931 goto bad;
1932 c->type = typdatum->value;
1933
1934 /* Convert the MLS fields if dealing with MLS policies */
1935 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1936 rc = mls_convert_context(args->oldp, args->newp, c);
1937 if (rc)
1938 goto bad;
1939 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1940 /*
1941 * Switching between MLS and non-MLS policy:
1942 * free any storage used by the MLS fields in the
1943 * context for all existing entries in the sidtab.
1944 */
1945 mls_context_destroy(c);
1946 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1947 /*
1948 * Switching between non-MLS and MLS policy:
1949 * ensure that the MLS fields of the context for all
1950 * existing entries in the sidtab are filled in with a
1951 * suitable default value, likely taken from one of the
1952 * initial SIDs.
1953 */
1954 oc = args->newp->ocontexts[OCON_ISID];
1955 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1956 oc = oc->next;
1957 rc = -EINVAL;
1958 if (!oc) {
1959 printk(KERN_ERR "SELinux: unable to look up"
1960 " the initial SIDs list\n");
1961 goto bad;
1962 }
1963 range = &oc->context[0].range;
1964 rc = mls_range_set(c, range);
1965 if (rc)
1966 goto bad;
1967 }
1968
1969 /* Check the validity of the new context. */
1970 if (!policydb_context_isvalid(args->newp, c)) {
1971 rc = convert_context_handle_invalid_context(&oldc);
1972 if (rc)
1973 goto bad;
1974 }
1975
1976 context_destroy(&oldc);
1977
1978 rc = 0;
1979 out:
1980 return rc;
1981 bad:
1982 /* Map old representation to string and save it. */
1983 rc = context_struct_to_string(&oldc, &s, &len);
1984 if (rc)
1985 return rc;
1986 context_destroy(&oldc);
1987 context_destroy(c);
1988 c->str = s;
1989 c->len = len;
1990 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n",
1991 c->str);
1992 rc = 0;
1993 goto out;
1994 }
1995
1996 static void security_load_policycaps(void)
1997 {
1998 unsigned int i;
1999 struct ebitmap_node *node;
2000
2001 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
2002 POLICYDB_CAPABILITY_NETPEER);
2003 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
2004 POLICYDB_CAPABILITY_OPENPERM);
2005 selinux_policycap_extsockclass = ebitmap_get_bit(&policydb.policycaps,
2006 POLICYDB_CAPABILITY_EXTSOCKCLASS);
2007 selinux_policycap_alwaysnetwork = ebitmap_get_bit(&policydb.policycaps,
2008 POLICYDB_CAPABILITY_ALWAYSNETWORK);
2009 selinux_policycap_cgroupseclabel =
2010 ebitmap_get_bit(&policydb.policycaps,
2011 POLICYDB_CAPABILITY_CGROUPSECLABEL);
2012
2013 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2014 pr_info("SELinux: policy capability %s=%d\n",
2015 selinux_policycap_names[i],
2016 ebitmap_get_bit(&policydb.policycaps, i));
2017
2018 ebitmap_for_each_positive_bit(&policydb.policycaps, node, i) {
2019 if (i >= ARRAY_SIZE(selinux_policycap_names))
2020 pr_info("SELinux: unknown policy capability %u\n",
2021 i);
2022 }
2023 }
2024
2025 static int security_preserve_bools(struct policydb *p);
2026
2027 /**
2028 * security_load_policy - Load a security policy configuration.
2029 * @data: binary policy data
2030 * @len: length of data in bytes
2031 *
2032 * Load a new set of security policy configuration data,
2033 * validate it and convert the SID table as necessary.
2034 * This function will flush the access vector cache after
2035 * loading the new policy.
2036 */
2037 int security_load_policy(void *data, size_t len)
2038 {
2039 struct policydb *oldpolicydb, *newpolicydb;
2040 struct sidtab oldsidtab, newsidtab;
2041 struct selinux_mapping *oldmap, *map = NULL;
2042 struct convert_context_args args;
2043 u32 seqno;
2044 u16 map_size;
2045 int rc = 0;
2046 struct policy_file file = { data, len }, *fp = &file;
2047
2048 oldpolicydb = kzalloc(2 * sizeof(*oldpolicydb), GFP_KERNEL);
2049 if (!oldpolicydb) {
2050 rc = -ENOMEM;
2051 goto out;
2052 }
2053 newpolicydb = oldpolicydb + 1;
2054
2055 if (!ss_initialized) {
2056 avtab_cache_init();
2057 ebitmap_cache_init();
2058 rc = policydb_read(&policydb, fp);
2059 if (rc) {
2060 avtab_cache_destroy();
2061 ebitmap_cache_destroy();
2062 goto out;
2063 }
2064
2065 policydb.len = len;
2066 rc = selinux_set_mapping(&policydb, secclass_map,
2067 &current_mapping,
2068 &current_mapping_size);
2069 if (rc) {
2070 policydb_destroy(&policydb);
2071 avtab_cache_destroy();
2072 ebitmap_cache_destroy();
2073 goto out;
2074 }
2075
2076 rc = policydb_load_isids(&policydb, &sidtab);
2077 if (rc) {
2078 policydb_destroy(&policydb);
2079 avtab_cache_destroy();
2080 ebitmap_cache_destroy();
2081 goto out;
2082 }
2083
2084 security_load_policycaps();
2085 ss_initialized = 1;
2086 seqno = ++latest_granting;
2087 selinux_complete_init();
2088 avc_ss_reset(seqno);
2089 selnl_notify_policyload(seqno);
2090 selinux_status_update_policyload(seqno);
2091 selinux_netlbl_cache_invalidate();
2092 selinux_xfrm_notify_policyload();
2093 goto out;
2094 }
2095
2096 #if 0
2097 sidtab_hash_eval(&sidtab, "sids");
2098 #endif
2099
2100 rc = policydb_read(newpolicydb, fp);
2101 if (rc)
2102 goto out;
2103
2104 newpolicydb->len = len;
2105 /* If switching between different policy types, log MLS status */
2106 if (policydb.mls_enabled && !newpolicydb->mls_enabled)
2107 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
2108 else if (!policydb.mls_enabled && newpolicydb->mls_enabled)
2109 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
2110
2111 rc = policydb_load_isids(newpolicydb, &newsidtab);
2112 if (rc) {
2113 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
2114 policydb_destroy(newpolicydb);
2115 goto out;
2116 }
2117
2118 rc = selinux_set_mapping(newpolicydb, secclass_map, &map, &map_size);
2119 if (rc)
2120 goto err;
2121
2122 rc = security_preserve_bools(newpolicydb);
2123 if (rc) {
2124 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
2125 goto err;
2126 }
2127
2128 /* Clone the SID table. */
2129 sidtab_shutdown(&sidtab);
2130
2131 rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
2132 if (rc)
2133 goto err;
2134
2135 /*
2136 * Convert the internal representations of contexts
2137 * in the new SID table.
2138 */
2139 args.oldp = &policydb;
2140 args.newp = newpolicydb;
2141 rc = sidtab_map(&newsidtab, convert_context, &args);
2142 if (rc) {
2143 printk(KERN_ERR "SELinux: unable to convert the internal"
2144 " representation of contexts in the new SID"
2145 " table\n");
2146 goto err;
2147 }
2148
2149 /* Save the old policydb and SID table to free later. */
2150 memcpy(oldpolicydb, &policydb, sizeof(policydb));
2151 sidtab_set(&oldsidtab, &sidtab);
2152
2153 /* Install the new policydb and SID table. */
2154 write_lock_irq(&policy_rwlock);
2155 memcpy(&policydb, newpolicydb, sizeof(policydb));
2156 sidtab_set(&sidtab, &newsidtab);
2157 security_load_policycaps();
2158 oldmap = current_mapping;
2159 current_mapping = map;
2160 current_mapping_size = map_size;
2161 seqno = ++latest_granting;
2162 write_unlock_irq(&policy_rwlock);
2163
2164 /* Free the old policydb and SID table. */
2165 policydb_destroy(oldpolicydb);
2166 sidtab_destroy(&oldsidtab);
2167 kfree(oldmap);
2168
2169 avc_ss_reset(seqno);
2170 selnl_notify_policyload(seqno);
2171 selinux_status_update_policyload(seqno);
2172 selinux_netlbl_cache_invalidate();
2173 selinux_xfrm_notify_policyload();
2174
2175 rc = 0;
2176 goto out;
2177
2178 err:
2179 kfree(map);
2180 sidtab_destroy(&newsidtab);
2181 policydb_destroy(newpolicydb);
2182
2183 out:
2184 kfree(oldpolicydb);
2185 return rc;
2186 }
2187
2188 size_t security_policydb_len(void)
2189 {
2190 size_t len;
2191
2192 read_lock(&policy_rwlock);
2193 len = policydb.len;
2194 read_unlock(&policy_rwlock);
2195
2196 return len;
2197 }
2198
2199 /**
2200 * security_port_sid - Obtain the SID for a port.
2201 * @protocol: protocol number
2202 * @port: port number
2203 * @out_sid: security identifier
2204 */
2205 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
2206 {
2207 struct ocontext *c;
2208 int rc = 0;
2209
2210 read_lock(&policy_rwlock);
2211
2212 c = policydb.ocontexts[OCON_PORT];
2213 while (c) {
2214 if (c->u.port.protocol == protocol &&
2215 c->u.port.low_port <= port &&
2216 c->u.port.high_port >= port)
2217 break;
2218 c = c->next;
2219 }
2220
2221 if (c) {
2222 if (!c->sid[0]) {
2223 rc = sidtab_context_to_sid(&sidtab,
2224 &c->context[0],
2225 &c->sid[0]);
2226 if (rc)
2227 goto out;
2228 }
2229 *out_sid = c->sid[0];
2230 } else {
2231 *out_sid = SECINITSID_PORT;
2232 }
2233
2234 out:
2235 read_unlock(&policy_rwlock);
2236 return rc;
2237 }
2238
2239 /**
2240 * security_pkey_sid - Obtain the SID for a pkey.
2241 * @subnet_prefix: Subnet Prefix
2242 * @pkey_num: pkey number
2243 * @out_sid: security identifier
2244 */
2245 int security_ib_pkey_sid(u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2246 {
2247 struct ocontext *c;
2248 int rc = 0;
2249
2250 read_lock(&policy_rwlock);
2251
2252 c = policydb.ocontexts[OCON_IBPKEY];
2253 while (c) {
2254 if (c->u.ibpkey.low_pkey <= pkey_num &&
2255 c->u.ibpkey.high_pkey >= pkey_num &&
2256 c->u.ibpkey.subnet_prefix == subnet_prefix)
2257 break;
2258
2259 c = c->next;
2260 }
2261
2262 if (c) {
2263 if (!c->sid[0]) {
2264 rc = sidtab_context_to_sid(&sidtab,
2265 &c->context[0],
2266 &c->sid[0]);
2267 if (rc)
2268 goto out;
2269 }
2270 *out_sid = c->sid[0];
2271 } else
2272 *out_sid = SECINITSID_UNLABELED;
2273
2274 out:
2275 read_unlock(&policy_rwlock);
2276 return rc;
2277 }
2278
2279 /**
2280 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2281 * @dev_name: device name
2282 * @port: port number
2283 * @out_sid: security identifier
2284 */
2285 int security_ib_endport_sid(const char *dev_name, u8 port_num, u32 *out_sid)
2286 {
2287 struct ocontext *c;
2288 int rc = 0;
2289
2290 read_lock(&policy_rwlock);
2291
2292 c = policydb.ocontexts[OCON_IBENDPORT];
2293 while (c) {
2294 if (c->u.ibendport.port == port_num &&
2295 !strncmp(c->u.ibendport.dev_name,
2296 dev_name,
2297 IB_DEVICE_NAME_MAX))
2298 break;
2299
2300 c = c->next;
2301 }
2302
2303 if (c) {
2304 if (!c->sid[0]) {
2305 rc = sidtab_context_to_sid(&sidtab,
2306 &c->context[0],
2307 &c->sid[0]);
2308 if (rc)
2309 goto out;
2310 }
2311 *out_sid = c->sid[0];
2312 } else
2313 *out_sid = SECINITSID_UNLABELED;
2314
2315 out:
2316 read_unlock(&policy_rwlock);
2317 return rc;
2318 }
2319
2320 /**
2321 * security_netif_sid - Obtain the SID for a network interface.
2322 * @name: interface name
2323 * @if_sid: interface SID
2324 */
2325 int security_netif_sid(char *name, u32 *if_sid)
2326 {
2327 int rc = 0;
2328 struct ocontext *c;
2329
2330 read_lock(&policy_rwlock);
2331
2332 c = policydb.ocontexts[OCON_NETIF];
2333 while (c) {
2334 if (strcmp(name, c->u.name) == 0)
2335 break;
2336 c = c->next;
2337 }
2338
2339 if (c) {
2340 if (!c->sid[0] || !c->sid[1]) {
2341 rc = sidtab_context_to_sid(&sidtab,
2342 &c->context[0],
2343 &c->sid[0]);
2344 if (rc)
2345 goto out;
2346 rc = sidtab_context_to_sid(&sidtab,
2347 &c->context[1],
2348 &c->sid[1]);
2349 if (rc)
2350 goto out;
2351 }
2352 *if_sid = c->sid[0];
2353 } else
2354 *if_sid = SECINITSID_NETIF;
2355
2356 out:
2357 read_unlock(&policy_rwlock);
2358 return rc;
2359 }
2360
2361 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2362 {
2363 int i, fail = 0;
2364
2365 for (i = 0; i < 4; i++)
2366 if (addr[i] != (input[i] & mask[i])) {
2367 fail = 1;
2368 break;
2369 }
2370
2371 return !fail;
2372 }
2373
2374 /**
2375 * security_node_sid - Obtain the SID for a node (host).
2376 * @domain: communication domain aka address family
2377 * @addrp: address
2378 * @addrlen: address length in bytes
2379 * @out_sid: security identifier
2380 */
2381 int security_node_sid(u16 domain,
2382 void *addrp,
2383 u32 addrlen,
2384 u32 *out_sid)
2385 {
2386 int rc;
2387 struct ocontext *c;
2388
2389 read_lock(&policy_rwlock);
2390
2391 switch (domain) {
2392 case AF_INET: {
2393 u32 addr;
2394
2395 rc = -EINVAL;
2396 if (addrlen != sizeof(u32))
2397 goto out;
2398
2399 addr = *((u32 *)addrp);
2400
2401 c = policydb.ocontexts[OCON_NODE];
2402 while (c) {
2403 if (c->u.node.addr == (addr & c->u.node.mask))
2404 break;
2405 c = c->next;
2406 }
2407 break;
2408 }
2409
2410 case AF_INET6:
2411 rc = -EINVAL;
2412 if (addrlen != sizeof(u64) * 2)
2413 goto out;
2414 c = policydb.ocontexts[OCON_NODE6];
2415 while (c) {
2416 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2417 c->u.node6.mask))
2418 break;
2419 c = c->next;
2420 }
2421 break;
2422
2423 default:
2424 rc = 0;
2425 *out_sid = SECINITSID_NODE;
2426 goto out;
2427 }
2428
2429 if (c) {
2430 if (!c->sid[0]) {
2431 rc = sidtab_context_to_sid(&sidtab,
2432 &c->context[0],
2433 &c->sid[0]);
2434 if (rc)
2435 goto out;
2436 }
2437 *out_sid = c->sid[0];
2438 } else {
2439 *out_sid = SECINITSID_NODE;
2440 }
2441
2442 rc = 0;
2443 out:
2444 read_unlock(&policy_rwlock);
2445 return rc;
2446 }
2447
2448 #define SIDS_NEL 25
2449
2450 /**
2451 * security_get_user_sids - Obtain reachable SIDs for a user.
2452 * @fromsid: starting SID
2453 * @username: username
2454 * @sids: array of reachable SIDs for user
2455 * @nel: number of elements in @sids
2456 *
2457 * Generate the set of SIDs for legal security contexts
2458 * for a given user that can be reached by @fromsid.
2459 * Set *@sids to point to a dynamically allocated
2460 * array containing the set of SIDs. Set *@nel to the
2461 * number of elements in the array.
2462 */
2463
2464 int security_get_user_sids(u32 fromsid,
2465 char *username,
2466 u32 **sids,
2467 u32 *nel)
2468 {
2469 struct context *fromcon, usercon;
2470 u32 *mysids = NULL, *mysids2, sid;
2471 u32 mynel = 0, maxnel = SIDS_NEL;
2472 struct user_datum *user;
2473 struct role_datum *role;
2474 struct ebitmap_node *rnode, *tnode;
2475 int rc = 0, i, j;
2476
2477 *sids = NULL;
2478 *nel = 0;
2479
2480 if (!ss_initialized)
2481 goto out;
2482
2483 read_lock(&policy_rwlock);
2484
2485 context_init(&usercon);
2486
2487 rc = -EINVAL;
2488 fromcon = sidtab_search(&sidtab, fromsid);
2489 if (!fromcon)
2490 goto out_unlock;
2491
2492 rc = -EINVAL;
2493 user = hashtab_search(policydb.p_users.table, username);
2494 if (!user)
2495 goto out_unlock;
2496
2497 usercon.user = user->value;
2498
2499 rc = -ENOMEM;
2500 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2501 if (!mysids)
2502 goto out_unlock;
2503
2504 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2505 role = policydb.role_val_to_struct[i];
2506 usercon.role = i + 1;
2507 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2508 usercon.type = j + 1;
2509
2510 if (mls_setup_user_range(fromcon, user, &usercon))
2511 continue;
2512
2513 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2514 if (rc)
2515 goto out_unlock;
2516 if (mynel < maxnel) {
2517 mysids[mynel++] = sid;
2518 } else {
2519 rc = -ENOMEM;
2520 maxnel += SIDS_NEL;
2521 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2522 if (!mysids2)
2523 goto out_unlock;
2524 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2525 kfree(mysids);
2526 mysids = mysids2;
2527 mysids[mynel++] = sid;
2528 }
2529 }
2530 }
2531 rc = 0;
2532 out_unlock:
2533 read_unlock(&policy_rwlock);
2534 if (rc || !mynel) {
2535 kfree(mysids);
2536 goto out;
2537 }
2538
2539 rc = -ENOMEM;
2540 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2541 if (!mysids2) {
2542 kfree(mysids);
2543 goto out;
2544 }
2545 for (i = 0, j = 0; i < mynel; i++) {
2546 struct av_decision dummy_avd;
2547 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2548 SECCLASS_PROCESS, /* kernel value */
2549 PROCESS__TRANSITION, AVC_STRICT,
2550 &dummy_avd);
2551 if (!rc)
2552 mysids2[j++] = mysids[i];
2553 cond_resched();
2554 }
2555 rc = 0;
2556 kfree(mysids);
2557 *sids = mysids2;
2558 *nel = j;
2559 out:
2560 return rc;
2561 }
2562
2563 /**
2564 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2565 * @fstype: filesystem type
2566 * @path: path from root of mount
2567 * @sclass: file security class
2568 * @sid: SID for path
2569 *
2570 * Obtain a SID to use for a file in a filesystem that
2571 * cannot support xattr or use a fixed labeling behavior like
2572 * transition SIDs or task SIDs.
2573 *
2574 * The caller must acquire the policy_rwlock before calling this function.
2575 */
2576 static inline int __security_genfs_sid(const char *fstype,
2577 char *path,
2578 u16 orig_sclass,
2579 u32 *sid)
2580 {
2581 int len;
2582 u16 sclass;
2583 struct genfs *genfs;
2584 struct ocontext *c;
2585 int rc, cmp = 0;
2586
2587 while (path[0] == '/' && path[1] == '/')
2588 path++;
2589
2590 sclass = unmap_class(orig_sclass);
2591 *sid = SECINITSID_UNLABELED;
2592
2593 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2594 cmp = strcmp(fstype, genfs->fstype);
2595 if (cmp <= 0)
2596 break;
2597 }
2598
2599 rc = -ENOENT;
2600 if (!genfs || cmp)
2601 goto out;
2602
2603 for (c = genfs->head; c; c = c->next) {
2604 len = strlen(c->u.name);
2605 if ((!c->v.sclass || sclass == c->v.sclass) &&
2606 (strncmp(c->u.name, path, len) == 0))
2607 break;
2608 }
2609
2610 rc = -ENOENT;
2611 if (!c)
2612 goto out;
2613
2614 if (!c->sid[0]) {
2615 rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]);
2616 if (rc)
2617 goto out;
2618 }
2619
2620 *sid = c->sid[0];
2621 rc = 0;
2622 out:
2623 return rc;
2624 }
2625
2626 /**
2627 * security_genfs_sid - Obtain a SID for a file in a filesystem
2628 * @fstype: filesystem type
2629 * @path: path from root of mount
2630 * @sclass: file security class
2631 * @sid: SID for path
2632 *
2633 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2634 * it afterward.
2635 */
2636 int security_genfs_sid(const char *fstype,
2637 char *path,
2638 u16 orig_sclass,
2639 u32 *sid)
2640 {
2641 int retval;
2642
2643 read_lock(&policy_rwlock);
2644 retval = __security_genfs_sid(fstype, path, orig_sclass, sid);
2645 read_unlock(&policy_rwlock);
2646 return retval;
2647 }
2648
2649 /**
2650 * security_fs_use - Determine how to handle labeling for a filesystem.
2651 * @sb: superblock in question
2652 */
2653 int security_fs_use(struct super_block *sb)
2654 {
2655 int rc = 0;
2656 struct ocontext *c;
2657 struct superblock_security_struct *sbsec = sb->s_security;
2658 const char *fstype = sb->s_type->name;
2659
2660 read_lock(&policy_rwlock);
2661
2662 c = policydb.ocontexts[OCON_FSUSE];
2663 while (c) {
2664 if (strcmp(fstype, c->u.name) == 0)
2665 break;
2666 c = c->next;
2667 }
2668
2669 if (c) {
2670 sbsec->behavior = c->v.behavior;
2671 if (!c->sid[0]) {
2672 rc = sidtab_context_to_sid(&sidtab, &c->context[0],
2673 &c->sid[0]);
2674 if (rc)
2675 goto out;
2676 }
2677 sbsec->sid = c->sid[0];
2678 } else {
2679 rc = __security_genfs_sid(fstype, "/", SECCLASS_DIR,
2680 &sbsec->sid);
2681 if (rc) {
2682 sbsec->behavior = SECURITY_FS_USE_NONE;
2683 rc = 0;
2684 } else {
2685 sbsec->behavior = SECURITY_FS_USE_GENFS;
2686 }
2687 }
2688
2689 out:
2690 read_unlock(&policy_rwlock);
2691 return rc;
2692 }
2693
2694 int security_get_bools(int *len, char ***names, int **values)
2695 {
2696 int i, rc;
2697
2698 read_lock(&policy_rwlock);
2699 *names = NULL;
2700 *values = NULL;
2701
2702 rc = 0;
2703 *len = policydb.p_bools.nprim;
2704 if (!*len)
2705 goto out;
2706
2707 rc = -ENOMEM;
2708 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2709 if (!*names)
2710 goto err;
2711
2712 rc = -ENOMEM;
2713 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2714 if (!*values)
2715 goto err;
2716
2717 for (i = 0; i < *len; i++) {
2718 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2719
2720 rc = -ENOMEM;
2721 (*names)[i] = kstrdup(sym_name(&policydb, SYM_BOOLS, i), GFP_ATOMIC);
2722 if (!(*names)[i])
2723 goto err;
2724 }
2725 rc = 0;
2726 out:
2727 read_unlock(&policy_rwlock);
2728 return rc;
2729 err:
2730 if (*names) {
2731 for (i = 0; i < *len; i++)
2732 kfree((*names)[i]);
2733 }
2734 kfree(*values);
2735 goto out;
2736 }
2737
2738
2739 int security_set_bools(int len, int *values)
2740 {
2741 int i, rc;
2742 int lenp, seqno = 0;
2743 struct cond_node *cur;
2744
2745 write_lock_irq(&policy_rwlock);
2746
2747 rc = -EFAULT;
2748 lenp = policydb.p_bools.nprim;
2749 if (len != lenp)
2750 goto out;
2751
2752 for (i = 0; i < len; i++) {
2753 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2754 audit_log(current->audit_context, GFP_ATOMIC,
2755 AUDIT_MAC_CONFIG_CHANGE,
2756 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2757 sym_name(&policydb, SYM_BOOLS, i),
2758 !!values[i],
2759 policydb.bool_val_to_struct[i]->state,
2760 from_kuid(&init_user_ns, audit_get_loginuid(current)),
2761 audit_get_sessionid(current));
2762 }
2763 if (values[i])
2764 policydb.bool_val_to_struct[i]->state = 1;
2765 else
2766 policydb.bool_val_to_struct[i]->state = 0;
2767 }
2768
2769 for (cur = policydb.cond_list; cur; cur = cur->next) {
2770 rc = evaluate_cond_node(&policydb, cur);
2771 if (rc)
2772 goto out;
2773 }
2774
2775 seqno = ++latest_granting;
2776 rc = 0;
2777 out:
2778 write_unlock_irq(&policy_rwlock);
2779 if (!rc) {
2780 avc_ss_reset(seqno);
2781 selnl_notify_policyload(seqno);
2782 selinux_status_update_policyload(seqno);
2783 selinux_xfrm_notify_policyload();
2784 }
2785 return rc;
2786 }
2787
2788 int security_get_bool_value(int index)
2789 {
2790 int rc;
2791 int len;
2792
2793 read_lock(&policy_rwlock);
2794
2795 rc = -EFAULT;
2796 len = policydb.p_bools.nprim;
2797 if (index >= len)
2798 goto out;
2799
2800 rc = policydb.bool_val_to_struct[index]->state;
2801 out:
2802 read_unlock(&policy_rwlock);
2803 return rc;
2804 }
2805
2806 static int security_preserve_bools(struct policydb *p)
2807 {
2808 int rc, nbools = 0, *bvalues = NULL, i;
2809 char **bnames = NULL;
2810 struct cond_bool_datum *booldatum;
2811 struct cond_node *cur;
2812
2813 rc = security_get_bools(&nbools, &bnames, &bvalues);
2814 if (rc)
2815 goto out;
2816 for (i = 0; i < nbools; i++) {
2817 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2818 if (booldatum)
2819 booldatum->state = bvalues[i];
2820 }
2821 for (cur = p->cond_list; cur; cur = cur->next) {
2822 rc = evaluate_cond_node(p, cur);
2823 if (rc)
2824 goto out;
2825 }
2826
2827 out:
2828 if (bnames) {
2829 for (i = 0; i < nbools; i++)
2830 kfree(bnames[i]);
2831 }
2832 kfree(bnames);
2833 kfree(bvalues);
2834 return rc;
2835 }
2836
2837 /*
2838 * security_sid_mls_copy() - computes a new sid based on the given
2839 * sid and the mls portion of mls_sid.
2840 */
2841 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2842 {
2843 struct context *context1;
2844 struct context *context2;
2845 struct context newcon;
2846 char *s;
2847 u32 len;
2848 int rc;
2849
2850 rc = 0;
2851 if (!ss_initialized || !policydb.mls_enabled) {
2852 *new_sid = sid;
2853 goto out;
2854 }
2855
2856 context_init(&newcon);
2857
2858 read_lock(&policy_rwlock);
2859
2860 rc = -EINVAL;
2861 context1 = sidtab_search(&sidtab, sid);
2862 if (!context1) {
2863 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2864 __func__, sid);
2865 goto out_unlock;
2866 }
2867
2868 rc = -EINVAL;
2869 context2 = sidtab_search(&sidtab, mls_sid);
2870 if (!context2) {
2871 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2872 __func__, mls_sid);
2873 goto out_unlock;
2874 }
2875
2876 newcon.user = context1->user;
2877 newcon.role = context1->role;
2878 newcon.type = context1->type;
2879 rc = mls_context_cpy(&newcon, context2);
2880 if (rc)
2881 goto out_unlock;
2882
2883 /* Check the validity of the new context. */
2884 if (!policydb_context_isvalid(&policydb, &newcon)) {
2885 rc = convert_context_handle_invalid_context(&newcon);
2886 if (rc) {
2887 if (!context_struct_to_string(&newcon, &s, &len)) {
2888 audit_log(current->audit_context,
2889 GFP_ATOMIC, AUDIT_SELINUX_ERR,
2890 "op=security_sid_mls_copy "
2891 "invalid_context=%s", s);
2892 kfree(s);
2893 }
2894 goto out_unlock;
2895 }
2896 }
2897
2898 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2899 out_unlock:
2900 read_unlock(&policy_rwlock);
2901 context_destroy(&newcon);
2902 out:
2903 return rc;
2904 }
2905
2906 /**
2907 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2908 * @nlbl_sid: NetLabel SID
2909 * @nlbl_type: NetLabel labeling protocol type
2910 * @xfrm_sid: XFRM SID
2911 *
2912 * Description:
2913 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2914 * resolved into a single SID it is returned via @peer_sid and the function
2915 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
2916 * returns a negative value. A table summarizing the behavior is below:
2917 *
2918 * | function return | @sid
2919 * ------------------------------+-----------------+-----------------
2920 * no peer labels | 0 | SECSID_NULL
2921 * single peer label | 0 | <peer_label>
2922 * multiple, consistent labels | 0 | <peer_label>
2923 * multiple, inconsistent labels | -<errno> | SECSID_NULL
2924 *
2925 */
2926 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2927 u32 xfrm_sid,
2928 u32 *peer_sid)
2929 {
2930 int rc;
2931 struct context *nlbl_ctx;
2932 struct context *xfrm_ctx;
2933
2934 *peer_sid = SECSID_NULL;
2935
2936 /* handle the common (which also happens to be the set of easy) cases
2937 * right away, these two if statements catch everything involving a
2938 * single or absent peer SID/label */
2939 if (xfrm_sid == SECSID_NULL) {
2940 *peer_sid = nlbl_sid;
2941 return 0;
2942 }
2943 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2944 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2945 * is present */
2946 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2947 *peer_sid = xfrm_sid;
2948 return 0;
2949 }
2950
2951 /* we don't need to check ss_initialized here since the only way both
2952 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2953 * security server was initialized and ss_initialized was true */
2954 if (!policydb.mls_enabled)
2955 return 0;
2956
2957 read_lock(&policy_rwlock);
2958
2959 rc = -EINVAL;
2960 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2961 if (!nlbl_ctx) {
2962 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2963 __func__, nlbl_sid);
2964 goto out;
2965 }
2966 rc = -EINVAL;
2967 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2968 if (!xfrm_ctx) {
2969 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2970 __func__, xfrm_sid);
2971 goto out;
2972 }
2973 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2974 if (rc)
2975 goto out;
2976
2977 /* at present NetLabel SIDs/labels really only carry MLS
2978 * information so if the MLS portion of the NetLabel SID
2979 * matches the MLS portion of the labeled XFRM SID/label
2980 * then pass along the XFRM SID as it is the most
2981 * expressive */
2982 *peer_sid = xfrm_sid;
2983 out:
2984 read_unlock(&policy_rwlock);
2985 return rc;
2986 }
2987
2988 static int get_classes_callback(void *k, void *d, void *args)
2989 {
2990 struct class_datum *datum = d;
2991 char *name = k, **classes = args;
2992 int value = datum->value - 1;
2993
2994 classes[value] = kstrdup(name, GFP_ATOMIC);
2995 if (!classes[value])
2996 return -ENOMEM;
2997
2998 return 0;
2999 }
3000
3001 int security_get_classes(char ***classes, int *nclasses)
3002 {
3003 int rc;
3004
3005 read_lock(&policy_rwlock);
3006
3007 rc = -ENOMEM;
3008 *nclasses = policydb.p_classes.nprim;
3009 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3010 if (!*classes)
3011 goto out;
3012
3013 rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
3014 *classes);
3015 if (rc) {
3016 int i;
3017 for (i = 0; i < *nclasses; i++)
3018 kfree((*classes)[i]);
3019 kfree(*classes);
3020 }
3021
3022 out:
3023 read_unlock(&policy_rwlock);
3024 return rc;
3025 }
3026
3027 static int get_permissions_callback(void *k, void *d, void *args)
3028 {
3029 struct perm_datum *datum = d;
3030 char *name = k, **perms = args;
3031 int value = datum->value - 1;
3032
3033 perms[value] = kstrdup(name, GFP_ATOMIC);
3034 if (!perms[value])
3035 return -ENOMEM;
3036
3037 return 0;
3038 }
3039
3040 int security_get_permissions(char *class, char ***perms, int *nperms)
3041 {
3042 int rc, i;
3043 struct class_datum *match;
3044
3045 read_lock(&policy_rwlock);
3046
3047 rc = -EINVAL;
3048 match = hashtab_search(policydb.p_classes.table, class);
3049 if (!match) {
3050 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
3051 __func__, class);
3052 goto out;
3053 }
3054
3055 rc = -ENOMEM;
3056 *nperms = match->permissions.nprim;
3057 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3058 if (!*perms)
3059 goto out;
3060
3061 if (match->comdatum) {
3062 rc = hashtab_map(match->comdatum->permissions.table,
3063 get_permissions_callback, *perms);
3064 if (rc)
3065 goto err;
3066 }
3067
3068 rc = hashtab_map(match->permissions.table, get_permissions_callback,
3069 *perms);
3070 if (rc)
3071 goto err;
3072
3073 out:
3074 read_unlock(&policy_rwlock);
3075 return rc;
3076
3077 err:
3078 read_unlock(&policy_rwlock);
3079 for (i = 0; i < *nperms; i++)
3080 kfree((*perms)[i]);
3081 kfree(*perms);
3082 return rc;
3083 }
3084
3085 int security_get_reject_unknown(void)
3086 {
3087 return policydb.reject_unknown;
3088 }
3089
3090 int security_get_allow_unknown(void)
3091 {
3092 return policydb.allow_unknown;
3093 }
3094
3095 /**
3096 * security_policycap_supported - Check for a specific policy capability
3097 * @req_cap: capability
3098 *
3099 * Description:
3100 * This function queries the currently loaded policy to see if it supports the
3101 * capability specified by @req_cap. Returns true (1) if the capability is
3102 * supported, false (0) if it isn't supported.
3103 *
3104 */
3105 int security_policycap_supported(unsigned int req_cap)
3106 {
3107 int rc;
3108
3109 read_lock(&policy_rwlock);
3110 rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
3111 read_unlock(&policy_rwlock);
3112
3113 return rc;
3114 }
3115
3116 struct selinux_audit_rule {
3117 u32 au_seqno;
3118 struct context au_ctxt;
3119 };
3120
3121 void selinux_audit_rule_free(void *vrule)
3122 {
3123 struct selinux_audit_rule *rule = vrule;
3124
3125 if (rule) {
3126 context_destroy(&rule->au_ctxt);
3127 kfree(rule);
3128 }
3129 }
3130
3131 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3132 {
3133 struct selinux_audit_rule *tmprule;
3134 struct role_datum *roledatum;
3135 struct type_datum *typedatum;
3136 struct user_datum *userdatum;
3137 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3138 int rc = 0;
3139
3140 *rule = NULL;
3141
3142 if (!ss_initialized)
3143 return -EOPNOTSUPP;
3144
3145 switch (field) {
3146 case AUDIT_SUBJ_USER:
3147 case AUDIT_SUBJ_ROLE:
3148 case AUDIT_SUBJ_TYPE:
3149 case AUDIT_OBJ_USER:
3150 case AUDIT_OBJ_ROLE:
3151 case AUDIT_OBJ_TYPE:
3152 /* only 'equals' and 'not equals' fit user, role, and type */
3153 if (op != Audit_equal && op != Audit_not_equal)
3154 return -EINVAL;
3155 break;
3156 case AUDIT_SUBJ_SEN:
3157 case AUDIT_SUBJ_CLR:
3158 case AUDIT_OBJ_LEV_LOW:
3159 case AUDIT_OBJ_LEV_HIGH:
3160 /* we do not allow a range, indicated by the presence of '-' */
3161 if (strchr(rulestr, '-'))
3162 return -EINVAL;
3163 break;
3164 default:
3165 /* only the above fields are valid */
3166 return -EINVAL;
3167 }
3168
3169 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3170 if (!tmprule)
3171 return -ENOMEM;
3172
3173 context_init(&tmprule->au_ctxt);
3174
3175 read_lock(&policy_rwlock);
3176
3177 tmprule->au_seqno = latest_granting;
3178
3179 switch (field) {
3180 case AUDIT_SUBJ_USER:
3181 case AUDIT_OBJ_USER:
3182 rc = -EINVAL;
3183 userdatum = hashtab_search(policydb.p_users.table, rulestr);
3184 if (!userdatum)
3185 goto out;
3186 tmprule->au_ctxt.user = userdatum->value;
3187 break;
3188 case AUDIT_SUBJ_ROLE:
3189 case AUDIT_OBJ_ROLE:
3190 rc = -EINVAL;
3191 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
3192 if (!roledatum)
3193 goto out;
3194 tmprule->au_ctxt.role = roledatum->value;
3195 break;
3196 case AUDIT_SUBJ_TYPE:
3197 case AUDIT_OBJ_TYPE:
3198 rc = -EINVAL;
3199 typedatum = hashtab_search(policydb.p_types.table, rulestr);
3200 if (!typedatum)
3201 goto out;
3202 tmprule->au_ctxt.type = typedatum->value;
3203 break;
3204 case AUDIT_SUBJ_SEN:
3205 case AUDIT_SUBJ_CLR:
3206 case AUDIT_OBJ_LEV_LOW:
3207 case AUDIT_OBJ_LEV_HIGH:
3208 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
3209 if (rc)
3210 goto out;
3211 break;
3212 }
3213 rc = 0;
3214 out:
3215 read_unlock(&policy_rwlock);
3216
3217 if (rc) {
3218 selinux_audit_rule_free(tmprule);
3219 tmprule = NULL;
3220 }
3221
3222 *rule = tmprule;
3223
3224 return rc;
3225 }
3226
3227 /* Check to see if the rule contains any selinux fields */
3228 int selinux_audit_rule_known(struct audit_krule *rule)
3229 {
3230 int i;
3231
3232 for (i = 0; i < rule->field_count; i++) {
3233 struct audit_field *f = &rule->fields[i];
3234 switch (f->type) {
3235 case AUDIT_SUBJ_USER:
3236 case AUDIT_SUBJ_ROLE:
3237 case AUDIT_SUBJ_TYPE:
3238 case AUDIT_SUBJ_SEN:
3239 case AUDIT_SUBJ_CLR:
3240 case AUDIT_OBJ_USER:
3241 case AUDIT_OBJ_ROLE:
3242 case AUDIT_OBJ_TYPE:
3243 case AUDIT_OBJ_LEV_LOW:
3244 case AUDIT_OBJ_LEV_HIGH:
3245 return 1;
3246 }
3247 }
3248
3249 return 0;
3250 }
3251
3252 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
3253 struct audit_context *actx)
3254 {
3255 struct context *ctxt;
3256 struct mls_level *level;
3257 struct selinux_audit_rule *rule = vrule;
3258 int match = 0;
3259
3260 if (unlikely(!rule)) {
3261 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3262 return -ENOENT;
3263 }
3264
3265 read_lock(&policy_rwlock);
3266
3267 if (rule->au_seqno < latest_granting) {
3268 match = -ESTALE;
3269 goto out;
3270 }
3271
3272 ctxt = sidtab_search(&sidtab, sid);
3273 if (unlikely(!ctxt)) {
3274 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3275 sid);
3276 match = -ENOENT;
3277 goto out;
3278 }
3279
3280 /* a field/op pair that is not caught here will simply fall through
3281 without a match */
3282 switch (field) {
3283 case AUDIT_SUBJ_USER:
3284 case AUDIT_OBJ_USER:
3285 switch (op) {
3286 case Audit_equal:
3287 match = (ctxt->user == rule->au_ctxt.user);
3288 break;
3289 case Audit_not_equal:
3290 match = (ctxt->user != rule->au_ctxt.user);
3291 break;
3292 }
3293 break;
3294 case AUDIT_SUBJ_ROLE:
3295 case AUDIT_OBJ_ROLE:
3296 switch (op) {
3297 case Audit_equal:
3298 match = (ctxt->role == rule->au_ctxt.role);
3299 break;
3300 case Audit_not_equal:
3301 match = (ctxt->role != rule->au_ctxt.role);
3302 break;
3303 }
3304 break;
3305 case AUDIT_SUBJ_TYPE:
3306 case AUDIT_OBJ_TYPE:
3307 switch (op) {
3308 case Audit_equal:
3309 match = (ctxt->type == rule->au_ctxt.type);
3310 break;
3311 case Audit_not_equal:
3312 match = (ctxt->type != rule->au_ctxt.type);
3313 break;
3314 }
3315 break;
3316 case AUDIT_SUBJ_SEN:
3317 case AUDIT_SUBJ_CLR:
3318 case AUDIT_OBJ_LEV_LOW:
3319 case AUDIT_OBJ_LEV_HIGH:
3320 level = ((field == AUDIT_SUBJ_SEN ||
3321 field == AUDIT_OBJ_LEV_LOW) ?
3322 &ctxt->range.level[0] : &ctxt->range.level[1]);
3323 switch (op) {
3324 case Audit_equal:
3325 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3326 level);
3327 break;
3328 case Audit_not_equal:
3329 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3330 level);
3331 break;
3332 case Audit_lt:
3333 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3334 level) &&
3335 !mls_level_eq(&rule->au_ctxt.range.level[0],
3336 level));
3337 break;
3338 case Audit_le:
3339 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3340 level);
3341 break;
3342 case Audit_gt:
3343 match = (mls_level_dom(level,
3344 &rule->au_ctxt.range.level[0]) &&
3345 !mls_level_eq(level,
3346 &rule->au_ctxt.range.level[0]));
3347 break;
3348 case Audit_ge:
3349 match = mls_level_dom(level,
3350 &rule->au_ctxt.range.level[0]);
3351 break;
3352 }
3353 }
3354
3355 out:
3356 read_unlock(&policy_rwlock);
3357 return match;
3358 }
3359
3360 static int (*aurule_callback)(void) = audit_update_lsm_rules;
3361
3362 static int aurule_avc_callback(u32 event)
3363 {
3364 int err = 0;
3365
3366 if (event == AVC_CALLBACK_RESET && aurule_callback)
3367 err = aurule_callback();
3368 return err;
3369 }
3370
3371 static int __init aurule_init(void)
3372 {
3373 int err;
3374
3375 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3376 if (err)
3377 panic("avc_add_callback() failed, error %d\n", err);
3378
3379 return err;
3380 }
3381 __initcall(aurule_init);
3382
3383 #ifdef CONFIG_NETLABEL
3384 /**
3385 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3386 * @secattr: the NetLabel packet security attributes
3387 * @sid: the SELinux SID
3388 *
3389 * Description:
3390 * Attempt to cache the context in @ctx, which was derived from the packet in
3391 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3392 * already been initialized.
3393 *
3394 */
3395 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3396 u32 sid)
3397 {
3398 u32 *sid_cache;
3399
3400 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3401 if (sid_cache == NULL)
3402 return;
3403 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3404 if (secattr->cache == NULL) {
3405 kfree(sid_cache);
3406 return;
3407 }
3408
3409 *sid_cache = sid;
3410 secattr->cache->free = kfree;
3411 secattr->cache->data = sid_cache;
3412 secattr->flags |= NETLBL_SECATTR_CACHE;
3413 }
3414
3415 /**
3416 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3417 * @secattr: the NetLabel packet security attributes
3418 * @sid: the SELinux SID
3419 *
3420 * Description:
3421 * Convert the given NetLabel security attributes in @secattr into a
3422 * SELinux SID. If the @secattr field does not contain a full SELinux
3423 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3424 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3425 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3426 * conversion for future lookups. Returns zero on success, negative values on
3427 * failure.
3428 *
3429 */
3430 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3431 u32 *sid)
3432 {
3433 int rc;
3434 struct context *ctx;
3435 struct context ctx_new;
3436
3437 if (!ss_initialized) {
3438 *sid = SECSID_NULL;
3439 return 0;
3440 }
3441
3442 read_lock(&policy_rwlock);
3443
3444 if (secattr->flags & NETLBL_SECATTR_CACHE)
3445 *sid = *(u32 *)secattr->cache->data;
3446 else if (secattr->flags & NETLBL_SECATTR_SECID)
3447 *sid = secattr->attr.secid;
3448 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3449 rc = -EIDRM;
3450 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3451 if (ctx == NULL)
3452 goto out;
3453
3454 context_init(&ctx_new);
3455 ctx_new.user = ctx->user;
3456 ctx_new.role = ctx->role;
3457 ctx_new.type = ctx->type;
3458 mls_import_netlbl_lvl(&ctx_new, secattr);
3459 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3460 rc = mls_import_netlbl_cat(&ctx_new, secattr);
3461 if (rc)
3462 goto out;
3463 }
3464 rc = -EIDRM;
3465 if (!mls_context_isvalid(&policydb, &ctx_new))
3466 goto out_free;
3467
3468 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3469 if (rc)
3470 goto out_free;
3471
3472 security_netlbl_cache_add(secattr, *sid);
3473
3474 ebitmap_destroy(&ctx_new.range.level[0].cat);
3475 } else
3476 *sid = SECSID_NULL;
3477
3478 read_unlock(&policy_rwlock);
3479 return 0;
3480 out_free:
3481 ebitmap_destroy(&ctx_new.range.level[0].cat);
3482 out:
3483 read_unlock(&policy_rwlock);
3484 return rc;
3485 }
3486
3487 /**
3488 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3489 * @sid: the SELinux SID
3490 * @secattr: the NetLabel packet security attributes
3491 *
3492 * Description:
3493 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3494 * Returns zero on success, negative values on failure.
3495 *
3496 */
3497 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3498 {
3499 int rc;
3500 struct context *ctx;
3501
3502 if (!ss_initialized)
3503 return 0;
3504
3505 read_lock(&policy_rwlock);
3506
3507 rc = -ENOENT;
3508 ctx = sidtab_search(&sidtab, sid);
3509 if (ctx == NULL)
3510 goto out;
3511
3512 rc = -ENOMEM;
3513 secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1),
3514 GFP_ATOMIC);
3515 if (secattr->domain == NULL)
3516 goto out;
3517
3518 secattr->attr.secid = sid;
3519 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3520 mls_export_netlbl_lvl(ctx, secattr);
3521 rc = mls_export_netlbl_cat(ctx, secattr);
3522 out:
3523 read_unlock(&policy_rwlock);
3524 return rc;
3525 }
3526 #endif /* CONFIG_NETLABEL */
3527
3528 /**
3529 * security_read_policy - read the policy.
3530 * @data: binary policy data
3531 * @len: length of data in bytes
3532 *
3533 */
3534 int security_read_policy(void **data, size_t *len)
3535 {
3536 int rc;
3537 struct policy_file fp;
3538
3539 if (!ss_initialized)
3540 return -EINVAL;
3541
3542 *len = security_policydb_len();
3543
3544 *data = vmalloc_user(*len);
3545 if (!*data)
3546 return -ENOMEM;
3547
3548 fp.data = *data;
3549 fp.len = *len;
3550
3551 read_lock(&policy_rwlock);
3552 rc = policydb_write(&policydb, &fp);
3553 read_unlock(&policy_rwlock);
3554
3555 if (rc)
3556 return rc;
3557
3558 *len = (unsigned long)fp.data - (unsigned long)*data;
3559 return 0;
3560
3561 }
Linux with added FPC-III support