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[GitHub/mt8127/android_kernel_alcatel_ttab.git] / security / selinux / ss / services.c
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 int selinux_policycap_netpeer;
74 int selinux_policycap_openperm;
75
76 static DEFINE_RWLOCK(policy_rwlock);
77
78 static struct sidtab sidtab;
79 struct policydb policydb;
80 int ss_initialized;
81
82 /*
83 * The largest sequence number that has been used when
84 * providing an access decision to the access vector cache.
85 * The sequence number only changes when a policy change
86 * occurs.
87 */
88 static u32 latest_granting;
89
90 /* Forward declaration. */
91 static int context_struct_to_string(struct context *context, char **scontext,
92 u32 *scontext_len);
93
94 static void context_struct_compute_av(struct context *scontext,
95 struct context *tcontext,
96 u16 tclass,
97 struct av_decision *avd);
98
99 struct selinux_mapping {
100 u16 value; /* policy value */
101 unsigned num_perms;
102 u32 perms[sizeof(u32) * 8];
103 };
104
105 static struct selinux_mapping *current_mapping;
106 static u16 current_mapping_size;
107
108 static int selinux_set_mapping(struct policydb *pol,
109 struct security_class_mapping *map,
110 struct selinux_mapping **out_map_p,
111 u16 *out_map_size)
112 {
113 struct selinux_mapping *out_map = NULL;
114 size_t size = sizeof(struct selinux_mapping);
115 u16 i, j;
116 unsigned k;
117 bool print_unknown_handle = false;
118
119 /* Find number of classes in the input mapping */
120 if (!map)
121 return -EINVAL;
122 i = 0;
123 while (map[i].name)
124 i++;
125
126 /* Allocate space for the class records, plus one for class zero */
127 out_map = kcalloc(++i, size, GFP_ATOMIC);
128 if (!out_map)
129 return -ENOMEM;
130
131 /* Store the raw class and permission values */
132 j = 0;
133 while (map[j].name) {
134 struct security_class_mapping *p_in = map + (j++);
135 struct selinux_mapping *p_out = out_map + j;
136
137 /* An empty class string skips ahead */
138 if (!strcmp(p_in->name, "")) {
139 p_out->num_perms = 0;
140 continue;
141 }
142
143 p_out->value = string_to_security_class(pol, p_in->name);
144 if (!p_out->value) {
145 printk(KERN_INFO
146 "SELinux: Class %s not defined in policy.\n",
147 p_in->name);
148 if (pol->reject_unknown)
149 goto err;
150 p_out->num_perms = 0;
151 print_unknown_handle = true;
152 continue;
153 }
154
155 k = 0;
156 while (p_in->perms && p_in->perms[k]) {
157 /* An empty permission string skips ahead */
158 if (!*p_in->perms[k]) {
159 k++;
160 continue;
161 }
162 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
163 p_in->perms[k]);
164 if (!p_out->perms[k]) {
165 printk(KERN_INFO
166 "SELinux: Permission %s in class %s not defined in policy.\n",
167 p_in->perms[k], p_in->name);
168 if (pol->reject_unknown)
169 goto err;
170 print_unknown_handle = true;
171 }
172
173 k++;
174 }
175 p_out->num_perms = k;
176 }
177
178 if (print_unknown_handle)
179 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
180 pol->allow_unknown ? "allowed" : "denied");
181
182 *out_map_p = out_map;
183 *out_map_size = i;
184 return 0;
185 err:
186 kfree(out_map);
187 return -EINVAL;
188 }
189
190 /*
191 * Get real, policy values from mapped values
192 */
193
194 static u16 unmap_class(u16 tclass)
195 {
196 if (tclass < current_mapping_size)
197 return current_mapping[tclass].value;
198
199 return tclass;
200 }
201
202 /*
203 * Get kernel value for class from its policy value
204 */
205 static u16 map_class(u16 pol_value)
206 {
207 u16 i;
208
209 for (i = 1; i < current_mapping_size; i++) {
210 if (current_mapping[i].value == pol_value)
211 return i;
212 }
213
214 return SECCLASS_NULL;
215 }
216
217 static void map_decision(u16 tclass, struct av_decision *avd,
218 int allow_unknown)
219 {
220 if (tclass < current_mapping_size) {
221 unsigned i, n = current_mapping[tclass].num_perms;
222 u32 result;
223
224 for (i = 0, result = 0; i < n; i++) {
225 if (avd->allowed & current_mapping[tclass].perms[i])
226 result |= 1<<i;
227 if (allow_unknown && !current_mapping[tclass].perms[i])
228 result |= 1<<i;
229 }
230 avd->allowed = result;
231
232 for (i = 0, result = 0; i < n; i++)
233 if (avd->auditallow & current_mapping[tclass].perms[i])
234 result |= 1<<i;
235 avd->auditallow = result;
236
237 for (i = 0, result = 0; i < n; i++) {
238 if (avd->auditdeny & current_mapping[tclass].perms[i])
239 result |= 1<<i;
240 if (!allow_unknown && !current_mapping[tclass].perms[i])
241 result |= 1<<i;
242 }
243 /*
244 * In case the kernel has a bug and requests a permission
245 * between num_perms and the maximum permission number, we
246 * should audit that denial
247 */
248 for (; i < (sizeof(u32)*8); i++)
249 result |= 1<<i;
250 avd->auditdeny = result;
251 }
252 }
253
254 int security_mls_enabled(void)
255 {
256 return policydb.mls_enabled;
257 }
258
259 /*
260 * Return the boolean value of a constraint expression
261 * when it is applied to the specified source and target
262 * security contexts.
263 *
264 * xcontext is a special beast... It is used by the validatetrans rules
265 * only. For these rules, scontext is the context before the transition,
266 * tcontext is the context after the transition, and xcontext is the context
267 * of the process performing the transition. All other callers of
268 * constraint_expr_eval should pass in NULL for xcontext.
269 */
270 static int constraint_expr_eval(struct context *scontext,
271 struct context *tcontext,
272 struct context *xcontext,
273 struct constraint_expr *cexpr)
274 {
275 u32 val1, val2;
276 struct context *c;
277 struct role_datum *r1, *r2;
278 struct mls_level *l1, *l2;
279 struct constraint_expr *e;
280 int s[CEXPR_MAXDEPTH];
281 int sp = -1;
282
283 for (e = cexpr; e; e = e->next) {
284 switch (e->expr_type) {
285 case CEXPR_NOT:
286 BUG_ON(sp < 0);
287 s[sp] = !s[sp];
288 break;
289 case CEXPR_AND:
290 BUG_ON(sp < 1);
291 sp--;
292 s[sp] &= s[sp + 1];
293 break;
294 case CEXPR_OR:
295 BUG_ON(sp < 1);
296 sp--;
297 s[sp] |= s[sp + 1];
298 break;
299 case CEXPR_ATTR:
300 if (sp == (CEXPR_MAXDEPTH - 1))
301 return 0;
302 switch (e->attr) {
303 case CEXPR_USER:
304 val1 = scontext->user;
305 val2 = tcontext->user;
306 break;
307 case CEXPR_TYPE:
308 val1 = scontext->type;
309 val2 = tcontext->type;
310 break;
311 case CEXPR_ROLE:
312 val1 = scontext->role;
313 val2 = tcontext->role;
314 r1 = policydb.role_val_to_struct[val1 - 1];
315 r2 = policydb.role_val_to_struct[val2 - 1];
316 switch (e->op) {
317 case CEXPR_DOM:
318 s[++sp] = ebitmap_get_bit(&r1->dominates,
319 val2 - 1);
320 continue;
321 case CEXPR_DOMBY:
322 s[++sp] = ebitmap_get_bit(&r2->dominates,
323 val1 - 1);
324 continue;
325 case CEXPR_INCOMP:
326 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
327 val2 - 1) &&
328 !ebitmap_get_bit(&r2->dominates,
329 val1 - 1));
330 continue;
331 default:
332 break;
333 }
334 break;
335 case CEXPR_L1L2:
336 l1 = &(scontext->range.level[0]);
337 l2 = &(tcontext->range.level[0]);
338 goto mls_ops;
339 case CEXPR_L1H2:
340 l1 = &(scontext->range.level[0]);
341 l2 = &(tcontext->range.level[1]);
342 goto mls_ops;
343 case CEXPR_H1L2:
344 l1 = &(scontext->range.level[1]);
345 l2 = &(tcontext->range.level[0]);
346 goto mls_ops;
347 case CEXPR_H1H2:
348 l1 = &(scontext->range.level[1]);
349 l2 = &(tcontext->range.level[1]);
350 goto mls_ops;
351 case CEXPR_L1H1:
352 l1 = &(scontext->range.level[0]);
353 l2 = &(scontext->range.level[1]);
354 goto mls_ops;
355 case CEXPR_L2H2:
356 l1 = &(tcontext->range.level[0]);
357 l2 = &(tcontext->range.level[1]);
358 goto mls_ops;
359 mls_ops:
360 switch (e->op) {
361 case CEXPR_EQ:
362 s[++sp] = mls_level_eq(l1, l2);
363 continue;
364 case CEXPR_NEQ:
365 s[++sp] = !mls_level_eq(l1, l2);
366 continue;
367 case CEXPR_DOM:
368 s[++sp] = mls_level_dom(l1, l2);
369 continue;
370 case CEXPR_DOMBY:
371 s[++sp] = mls_level_dom(l2, l1);
372 continue;
373 case CEXPR_INCOMP:
374 s[++sp] = mls_level_incomp(l2, l1);
375 continue;
376 default:
377 BUG();
378 return 0;
379 }
380 break;
381 default:
382 BUG();
383 return 0;
384 }
385
386 switch (e->op) {
387 case CEXPR_EQ:
388 s[++sp] = (val1 == val2);
389 break;
390 case CEXPR_NEQ:
391 s[++sp] = (val1 != val2);
392 break;
393 default:
394 BUG();
395 return 0;
396 }
397 break;
398 case CEXPR_NAMES:
399 if (sp == (CEXPR_MAXDEPTH-1))
400 return 0;
401 c = scontext;
402 if (e->attr & CEXPR_TARGET)
403 c = tcontext;
404 else if (e->attr & CEXPR_XTARGET) {
405 c = xcontext;
406 if (!c) {
407 BUG();
408 return 0;
409 }
410 }
411 if (e->attr & CEXPR_USER)
412 val1 = c->user;
413 else if (e->attr & CEXPR_ROLE)
414 val1 = c->role;
415 else if (e->attr & CEXPR_TYPE)
416 val1 = c->type;
417 else {
418 BUG();
419 return 0;
420 }
421
422 switch (e->op) {
423 case CEXPR_EQ:
424 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
425 break;
426 case CEXPR_NEQ:
427 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
428 break;
429 default:
430 BUG();
431 return 0;
432 }
433 break;
434 default:
435 BUG();
436 return 0;
437 }
438 }
439
440 BUG_ON(sp != 0);
441 return s[0];
442 }
443
444 /*
445 * security_dump_masked_av - dumps masked permissions during
446 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
447 */
448 static int dump_masked_av_helper(void *k, void *d, void *args)
449 {
450 struct perm_datum *pdatum = d;
451 char **permission_names = args;
452
453 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
454
455 permission_names[pdatum->value - 1] = (char *)k;
456
457 return 0;
458 }
459
460 static void security_dump_masked_av(struct context *scontext,
461 struct context *tcontext,
462 u16 tclass,
463 u32 permissions,
464 const char *reason)
465 {
466 struct common_datum *common_dat;
467 struct class_datum *tclass_dat;
468 struct audit_buffer *ab;
469 char *tclass_name;
470 char *scontext_name = NULL;
471 char *tcontext_name = NULL;
472 char *permission_names[32];
473 int index;
474 u32 length;
475 bool need_comma = false;
476
477 if (!permissions)
478 return;
479
480 tclass_name = sym_name(&policydb, SYM_CLASSES, tclass - 1);
481 tclass_dat = policydb.class_val_to_struct[tclass - 1];
482 common_dat = tclass_dat->comdatum;
483
484 /* init permission_names */
485 if (common_dat &&
486 hashtab_map(common_dat->permissions.table,
487 dump_masked_av_helper, permission_names) < 0)
488 goto out;
489
490 if (hashtab_map(tclass_dat->permissions.table,
491 dump_masked_av_helper, permission_names) < 0)
492 goto out;
493
494 /* get scontext/tcontext in text form */
495 if (context_struct_to_string(scontext,
496 &scontext_name, &length) < 0)
497 goto out;
498
499 if (context_struct_to_string(tcontext,
500 &tcontext_name, &length) < 0)
501 goto out;
502
503 /* audit a message */
504 ab = audit_log_start(current->audit_context,
505 GFP_ATOMIC, AUDIT_SELINUX_ERR);
506 if (!ab)
507 goto out;
508
509 audit_log_format(ab, "op=security_compute_av reason=%s "
510 "scontext=%s tcontext=%s tclass=%s perms=",
511 reason, scontext_name, tcontext_name, tclass_name);
512
513 for (index = 0; index < 32; index++) {
514 u32 mask = (1 << index);
515
516 if ((mask & permissions) == 0)
517 continue;
518
519 audit_log_format(ab, "%s%s",
520 need_comma ? "," : "",
521 permission_names[index]
522 ? permission_names[index] : "????");
523 need_comma = true;
524 }
525 audit_log_end(ab);
526 out:
527 /* release scontext/tcontext */
528 kfree(tcontext_name);
529 kfree(scontext_name);
530
531 return;
532 }
533
534 /*
535 * security_boundary_permission - drops violated permissions
536 * on boundary constraint.
537 */
538 static void type_attribute_bounds_av(struct context *scontext,
539 struct context *tcontext,
540 u16 tclass,
541 struct av_decision *avd)
542 {
543 struct context lo_scontext;
544 struct context lo_tcontext;
545 struct av_decision lo_avd;
546 struct type_datum *source;
547 struct type_datum *target;
548 u32 masked = 0;
549
550 source = flex_array_get_ptr(policydb.type_val_to_struct_array,
551 scontext->type - 1);
552 BUG_ON(!source);
553
554 target = flex_array_get_ptr(policydb.type_val_to_struct_array,
555 tcontext->type - 1);
556 BUG_ON(!target);
557
558 if (source->bounds) {
559 memset(&lo_avd, 0, sizeof(lo_avd));
560
561 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
562 lo_scontext.type = source->bounds;
563
564 context_struct_compute_av(&lo_scontext,
565 tcontext,
566 tclass,
567 &lo_avd);
568 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
569 return; /* no masked permission */
570 masked = ~lo_avd.allowed & avd->allowed;
571 }
572
573 if (target->bounds) {
574 memset(&lo_avd, 0, sizeof(lo_avd));
575
576 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
577 lo_tcontext.type = target->bounds;
578
579 context_struct_compute_av(scontext,
580 &lo_tcontext,
581 tclass,
582 &lo_avd);
583 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
584 return; /* no masked permission */
585 masked = ~lo_avd.allowed & avd->allowed;
586 }
587
588 if (source->bounds && target->bounds) {
589 memset(&lo_avd, 0, sizeof(lo_avd));
590 /*
591 * lo_scontext and lo_tcontext are already
592 * set up.
593 */
594
595 context_struct_compute_av(&lo_scontext,
596 &lo_tcontext,
597 tclass,
598 &lo_avd);
599 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
600 return; /* no masked permission */
601 masked = ~lo_avd.allowed & avd->allowed;
602 }
603
604 if (masked) {
605 /* mask violated permissions */
606 avd->allowed &= ~masked;
607
608 /* audit masked permissions */
609 security_dump_masked_av(scontext, tcontext,
610 tclass, masked, "bounds");
611 }
612 }
613
614 /*
615 * Compute access vectors based on a context structure pair for
616 * the permissions in a particular class.
617 */
618 static void context_struct_compute_av(struct context *scontext,
619 struct context *tcontext,
620 u16 tclass,
621 struct av_decision *avd)
622 {
623 struct constraint_node *constraint;
624 struct role_allow *ra;
625 struct avtab_key avkey;
626 struct avtab_node *node;
627 struct class_datum *tclass_datum;
628 struct ebitmap *sattr, *tattr;
629 struct ebitmap_node *snode, *tnode;
630 unsigned int i, j;
631
632 avd->allowed = 0;
633 avd->auditallow = 0;
634 avd->auditdeny = 0xffffffff;
635
636 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
637 if (printk_ratelimit())
638 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass);
639 return;
640 }
641
642 tclass_datum = policydb.class_val_to_struct[tclass - 1];
643
644 /*
645 * If a specific type enforcement rule was defined for
646 * this permission check, then use it.
647 */
648 avkey.target_class = tclass;
649 avkey.specified = AVTAB_AV;
650 sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1);
651 BUG_ON(!sattr);
652 tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1);
653 BUG_ON(!tattr);
654 ebitmap_for_each_positive_bit(sattr, snode, i) {
655 ebitmap_for_each_positive_bit(tattr, tnode, j) {
656 avkey.source_type = i + 1;
657 avkey.target_type = j + 1;
658 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
659 node;
660 node = avtab_search_node_next(node, avkey.specified)) {
661 if (node->key.specified == AVTAB_ALLOWED)
662 avd->allowed |= node->datum.data;
663 else if (node->key.specified == AVTAB_AUDITALLOW)
664 avd->auditallow |= node->datum.data;
665 else if (node->key.specified == AVTAB_AUDITDENY)
666 avd->auditdeny &= node->datum.data;
667 }
668
669 /* Check conditional av table for additional permissions */
670 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
671
672 }
673 }
674
675 /*
676 * Remove any permissions prohibited by a constraint (this includes
677 * the MLS policy).
678 */
679 constraint = tclass_datum->constraints;
680 while (constraint) {
681 if ((constraint->permissions & (avd->allowed)) &&
682 !constraint_expr_eval(scontext, tcontext, NULL,
683 constraint->expr)) {
684 avd->allowed &= ~(constraint->permissions);
685 }
686 constraint = constraint->next;
687 }
688
689 /*
690 * If checking process transition permission and the
691 * role is changing, then check the (current_role, new_role)
692 * pair.
693 */
694 if (tclass == policydb.process_class &&
695 (avd->allowed & policydb.process_trans_perms) &&
696 scontext->role != tcontext->role) {
697 for (ra = policydb.role_allow; ra; ra = ra->next) {
698 if (scontext->role == ra->role &&
699 tcontext->role == ra->new_role)
700 break;
701 }
702 if (!ra)
703 avd->allowed &= ~policydb.process_trans_perms;
704 }
705
706 /*
707 * If the given source and target types have boundary
708 * constraint, lazy checks have to mask any violated
709 * permission and notice it to userspace via audit.
710 */
711 type_attribute_bounds_av(scontext, tcontext,
712 tclass, avd);
713 }
714
715 static int security_validtrans_handle_fail(struct context *ocontext,
716 struct context *ncontext,
717 struct context *tcontext,
718 u16 tclass)
719 {
720 char *o = NULL, *n = NULL, *t = NULL;
721 u32 olen, nlen, tlen;
722
723 if (context_struct_to_string(ocontext, &o, &olen))
724 goto out;
725 if (context_struct_to_string(ncontext, &n, &nlen))
726 goto out;
727 if (context_struct_to_string(tcontext, &t, &tlen))
728 goto out;
729 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
730 "security_validate_transition: denied for"
731 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
732 o, n, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
733 out:
734 kfree(o);
735 kfree(n);
736 kfree(t);
737
738 if (!selinux_enforcing)
739 return 0;
740 return -EPERM;
741 }
742
743 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
744 u16 orig_tclass)
745 {
746 struct context *ocontext;
747 struct context *ncontext;
748 struct context *tcontext;
749 struct class_datum *tclass_datum;
750 struct constraint_node *constraint;
751 u16 tclass;
752 int rc = 0;
753
754 if (!ss_initialized)
755 return 0;
756
757 read_lock(&policy_rwlock);
758
759 tclass = unmap_class(orig_tclass);
760
761 if (!tclass || tclass > policydb.p_classes.nprim) {
762 printk(KERN_ERR "SELinux: %s: unrecognized class %d\n",
763 __func__, tclass);
764 rc = -EINVAL;
765 goto out;
766 }
767 tclass_datum = policydb.class_val_to_struct[tclass - 1];
768
769 ocontext = sidtab_search(&sidtab, oldsid);
770 if (!ocontext) {
771 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
772 __func__, oldsid);
773 rc = -EINVAL;
774 goto out;
775 }
776
777 ncontext = sidtab_search(&sidtab, newsid);
778 if (!ncontext) {
779 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
780 __func__, newsid);
781 rc = -EINVAL;
782 goto out;
783 }
784
785 tcontext = sidtab_search(&sidtab, tasksid);
786 if (!tcontext) {
787 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
788 __func__, tasksid);
789 rc = -EINVAL;
790 goto out;
791 }
792
793 constraint = tclass_datum->validatetrans;
794 while (constraint) {
795 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
796 constraint->expr)) {
797 rc = security_validtrans_handle_fail(ocontext, ncontext,
798 tcontext, tclass);
799 goto out;
800 }
801 constraint = constraint->next;
802 }
803
804 out:
805 read_unlock(&policy_rwlock);
806 return rc;
807 }
808
809 /*
810 * security_bounded_transition - check whether the given
811 * transition is directed to bounded, or not.
812 * It returns 0, if @newsid is bounded by @oldsid.
813 * Otherwise, it returns error code.
814 *
815 * @oldsid : current security identifier
816 * @newsid : destinated security identifier
817 */
818 int security_bounded_transition(u32 old_sid, u32 new_sid)
819 {
820 struct context *old_context, *new_context;
821 struct type_datum *type;
822 int index;
823 int rc;
824
825 read_lock(&policy_rwlock);
826
827 rc = -EINVAL;
828 old_context = sidtab_search(&sidtab, old_sid);
829 if (!old_context) {
830 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
831 __func__, old_sid);
832 goto out;
833 }
834
835 rc = -EINVAL;
836 new_context = sidtab_search(&sidtab, new_sid);
837 if (!new_context) {
838 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
839 __func__, new_sid);
840 goto out;
841 }
842
843 rc = 0;
844 /* type/domain unchanged */
845 if (old_context->type == new_context->type)
846 goto out;
847
848 index = new_context->type;
849 while (true) {
850 type = flex_array_get_ptr(policydb.type_val_to_struct_array,
851 index - 1);
852 BUG_ON(!type);
853
854 /* not bounded anymore */
855 rc = -EPERM;
856 if (!type->bounds)
857 break;
858
859 /* @newsid is bounded by @oldsid */
860 rc = 0;
861 if (type->bounds == old_context->type)
862 break;
863
864 index = type->bounds;
865 }
866
867 if (rc) {
868 char *old_name = NULL;
869 char *new_name = NULL;
870 u32 length;
871
872 if (!context_struct_to_string(old_context,
873 &old_name, &length) &&
874 !context_struct_to_string(new_context,
875 &new_name, &length)) {
876 audit_log(current->audit_context,
877 GFP_ATOMIC, AUDIT_SELINUX_ERR,
878 "op=security_bounded_transition "
879 "result=denied "
880 "oldcontext=%s newcontext=%s",
881 old_name, new_name);
882 }
883 kfree(new_name);
884 kfree(old_name);
885 }
886 out:
887 read_unlock(&policy_rwlock);
888
889 return rc;
890 }
891
892 static void avd_init(struct av_decision *avd)
893 {
894 avd->allowed = 0;
895 avd->auditallow = 0;
896 avd->auditdeny = 0xffffffff;
897 avd->seqno = latest_granting;
898 avd->flags = 0;
899 }
900
901
902 /**
903 * security_compute_av - Compute access vector decisions.
904 * @ssid: source security identifier
905 * @tsid: target security identifier
906 * @tclass: target security class
907 * @avd: access vector decisions
908 *
909 * Compute a set of access vector decisions based on the
910 * SID pair (@ssid, @tsid) for the permissions in @tclass.
911 */
912 void security_compute_av(u32 ssid,
913 u32 tsid,
914 u16 orig_tclass,
915 struct av_decision *avd)
916 {
917 u16 tclass;
918 struct context *scontext = NULL, *tcontext = NULL;
919
920 read_lock(&policy_rwlock);
921 avd_init(avd);
922 if (!ss_initialized)
923 goto allow;
924
925 scontext = sidtab_search(&sidtab, ssid);
926 if (!scontext) {
927 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
928 __func__, ssid);
929 goto out;
930 }
931
932 /* permissive domain? */
933 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
934 avd->flags |= AVD_FLAGS_PERMISSIVE;
935
936 tcontext = sidtab_search(&sidtab, tsid);
937 if (!tcontext) {
938 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
939 __func__, tsid);
940 goto out;
941 }
942
943 tclass = unmap_class(orig_tclass);
944 if (unlikely(orig_tclass && !tclass)) {
945 if (policydb.allow_unknown)
946 goto allow;
947 goto out;
948 }
949 context_struct_compute_av(scontext, tcontext, tclass, avd);
950 map_decision(orig_tclass, avd, policydb.allow_unknown);
951 out:
952 read_unlock(&policy_rwlock);
953 return;
954 allow:
955 avd->allowed = 0xffffffff;
956 goto out;
957 }
958
959 void security_compute_av_user(u32 ssid,
960 u32 tsid,
961 u16 tclass,
962 struct av_decision *avd)
963 {
964 struct context *scontext = NULL, *tcontext = NULL;
965
966 read_lock(&policy_rwlock);
967 avd_init(avd);
968 if (!ss_initialized)
969 goto allow;
970
971 scontext = sidtab_search(&sidtab, ssid);
972 if (!scontext) {
973 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
974 __func__, ssid);
975 goto out;
976 }
977
978 /* permissive domain? */
979 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
980 avd->flags |= AVD_FLAGS_PERMISSIVE;
981
982 tcontext = sidtab_search(&sidtab, tsid);
983 if (!tcontext) {
984 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
985 __func__, tsid);
986 goto out;
987 }
988
989 if (unlikely(!tclass)) {
990 if (policydb.allow_unknown)
991 goto allow;
992 goto out;
993 }
994
995 context_struct_compute_av(scontext, tcontext, tclass, avd);
996 out:
997 read_unlock(&policy_rwlock);
998 return;
999 allow:
1000 avd->allowed = 0xffffffff;
1001 goto out;
1002 }
1003
1004 /*
1005 * Write the security context string representation of
1006 * the context structure `context' into a dynamically
1007 * allocated string of the correct size. Set `*scontext'
1008 * to point to this string and set `*scontext_len' to
1009 * the length of the string.
1010 */
1011 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
1012 {
1013 char *scontextp;
1014
1015 if (scontext)
1016 *scontext = NULL;
1017 *scontext_len = 0;
1018
1019 if (context->len) {
1020 *scontext_len = context->len;
1021 if (scontext) {
1022 *scontext = kstrdup(context->str, GFP_ATOMIC);
1023 if (!(*scontext))
1024 return -ENOMEM;
1025 }
1026 return 0;
1027 }
1028
1029 /* Compute the size of the context. */
1030 *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1;
1031 *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1;
1032 *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1;
1033 *scontext_len += mls_compute_context_len(context);
1034
1035 if (!scontext)
1036 return 0;
1037
1038 /* Allocate space for the context; caller must free this space. */
1039 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1040 if (!scontextp)
1041 return -ENOMEM;
1042 *scontext = scontextp;
1043
1044 /*
1045 * Copy the user name, role name and type name into the context.
1046 */
1047 sprintf(scontextp, "%s:%s:%s",
1048 sym_name(&policydb, SYM_USERS, context->user - 1),
1049 sym_name(&policydb, SYM_ROLES, context->role - 1),
1050 sym_name(&policydb, SYM_TYPES, context->type - 1));
1051 scontextp += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) +
1052 1 + strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) +
1053 1 + strlen(sym_name(&policydb, SYM_TYPES, context->type - 1));
1054
1055 mls_sid_to_context(context, &scontextp);
1056
1057 *scontextp = 0;
1058
1059 return 0;
1060 }
1061
1062 #include "initial_sid_to_string.h"
1063
1064 const char *security_get_initial_sid_context(u32 sid)
1065 {
1066 if (unlikely(sid > SECINITSID_NUM))
1067 return NULL;
1068 return initial_sid_to_string[sid];
1069 }
1070
1071 static int security_sid_to_context_core(u32 sid, char **scontext,
1072 u32 *scontext_len, int force)
1073 {
1074 struct context *context;
1075 int rc = 0;
1076
1077 if (scontext)
1078 *scontext = NULL;
1079 *scontext_len = 0;
1080
1081 if (!ss_initialized) {
1082 if (sid <= SECINITSID_NUM) {
1083 char *scontextp;
1084
1085 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1086 if (!scontext)
1087 goto out;
1088 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1089 if (!scontextp) {
1090 rc = -ENOMEM;
1091 goto out;
1092 }
1093 strcpy(scontextp, initial_sid_to_string[sid]);
1094 *scontext = scontextp;
1095 goto out;
1096 }
1097 printk(KERN_ERR "SELinux: %s: called before initial "
1098 "load_policy on unknown SID %d\n", __func__, sid);
1099 rc = -EINVAL;
1100 goto out;
1101 }
1102 read_lock(&policy_rwlock);
1103 if (force)
1104 context = sidtab_search_force(&sidtab, sid);
1105 else
1106 context = sidtab_search(&sidtab, sid);
1107 if (!context) {
1108 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1109 __func__, sid);
1110 rc = -EINVAL;
1111 goto out_unlock;
1112 }
1113 rc = context_struct_to_string(context, scontext, scontext_len);
1114 out_unlock:
1115 read_unlock(&policy_rwlock);
1116 out:
1117 return rc;
1118
1119 }
1120
1121 /**
1122 * security_sid_to_context - Obtain a context for a given SID.
1123 * @sid: security identifier, SID
1124 * @scontext: security context
1125 * @scontext_len: length in bytes
1126 *
1127 * Write the string representation of the context associated with @sid
1128 * into a dynamically allocated string of the correct size. Set @scontext
1129 * to point to this string and set @scontext_len to the length of the string.
1130 */
1131 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1132 {
1133 return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1134 }
1135
1136 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1137 {
1138 return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1139 }
1140
1141 /*
1142 * Caveat: Mutates scontext.
1143 */
1144 static int string_to_context_struct(struct policydb *pol,
1145 struct sidtab *sidtabp,
1146 char *scontext,
1147 u32 scontext_len,
1148 struct context *ctx,
1149 u32 def_sid)
1150 {
1151 struct role_datum *role;
1152 struct type_datum *typdatum;
1153 struct user_datum *usrdatum;
1154 char *scontextp, *p, oldc;
1155 int rc = 0;
1156
1157 context_init(ctx);
1158
1159 /* Parse the security context. */
1160
1161 rc = -EINVAL;
1162 scontextp = (char *) scontext;
1163
1164 /* Extract the user. */
1165 p = scontextp;
1166 while (*p && *p != ':')
1167 p++;
1168
1169 if (*p == 0)
1170 goto out;
1171
1172 *p++ = 0;
1173
1174 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1175 if (!usrdatum)
1176 goto out;
1177
1178 ctx->user = usrdatum->value;
1179
1180 /* Extract role. */
1181 scontextp = p;
1182 while (*p && *p != ':')
1183 p++;
1184
1185 if (*p == 0)
1186 goto out;
1187
1188 *p++ = 0;
1189
1190 role = hashtab_search(pol->p_roles.table, scontextp);
1191 if (!role)
1192 goto out;
1193 ctx->role = role->value;
1194
1195 /* Extract type. */
1196 scontextp = p;
1197 while (*p && *p != ':')
1198 p++;
1199 oldc = *p;
1200 *p++ = 0;
1201
1202 typdatum = hashtab_search(pol->p_types.table, scontextp);
1203 if (!typdatum || typdatum->attribute)
1204 goto out;
1205
1206 ctx->type = typdatum->value;
1207
1208 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1209 if (rc)
1210 goto out;
1211
1212 rc = -EINVAL;
1213 if ((p - scontext) < scontext_len)
1214 goto out;
1215
1216 /* Check the validity of the new context. */
1217 if (!policydb_context_isvalid(pol, ctx))
1218 goto out;
1219 rc = 0;
1220 out:
1221 if (rc)
1222 context_destroy(ctx);
1223 return rc;
1224 }
1225
1226 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1227 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1228 int force)
1229 {
1230 char *scontext2, *str = NULL;
1231 struct context context;
1232 int rc = 0;
1233
1234 /* An empty security context is never valid. */
1235 if (!scontext_len)
1236 return -EINVAL;
1237
1238 if (!ss_initialized) {
1239 int i;
1240
1241 for (i = 1; i < SECINITSID_NUM; i++) {
1242 if (!strcmp(initial_sid_to_string[i], scontext)) {
1243 *sid = i;
1244 return 0;
1245 }
1246 }
1247 *sid = SECINITSID_KERNEL;
1248 return 0;
1249 }
1250 *sid = SECSID_NULL;
1251
1252 /* Copy the string so that we can modify the copy as we parse it. */
1253 scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1254 if (!scontext2)
1255 return -ENOMEM;
1256 memcpy(scontext2, scontext, scontext_len);
1257 scontext2[scontext_len] = 0;
1258
1259 if (force) {
1260 /* Save another copy for storing in uninterpreted form */
1261 rc = -ENOMEM;
1262 str = kstrdup(scontext2, gfp_flags);
1263 if (!str)
1264 goto out;
1265 }
1266
1267 read_lock(&policy_rwlock);
1268 rc = string_to_context_struct(&policydb, &sidtab, scontext2,
1269 scontext_len, &context, def_sid);
1270 if (rc == -EINVAL && force) {
1271 context.str = str;
1272 context.len = scontext_len;
1273 str = NULL;
1274 } else if (rc)
1275 goto out_unlock;
1276 rc = sidtab_context_to_sid(&sidtab, &context, sid);
1277 context_destroy(&context);
1278 out_unlock:
1279 read_unlock(&policy_rwlock);
1280 out:
1281 kfree(scontext2);
1282 kfree(str);
1283 return rc;
1284 }
1285
1286 /**
1287 * security_context_to_sid - Obtain a SID for a given security context.
1288 * @scontext: security context
1289 * @scontext_len: length in bytes
1290 * @sid: security identifier, SID
1291 *
1292 * Obtains a SID associated with the security context that
1293 * has the string representation specified by @scontext.
1294 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1295 * memory is available, or 0 on success.
1296 */
1297 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
1298 {
1299 return security_context_to_sid_core(scontext, scontext_len,
1300 sid, SECSID_NULL, GFP_KERNEL, 0);
1301 }
1302
1303 /**
1304 * security_context_to_sid_default - Obtain a SID for a given security context,
1305 * falling back to specified default if needed.
1306 *
1307 * @scontext: security context
1308 * @scontext_len: length in bytes
1309 * @sid: security identifier, SID
1310 * @def_sid: default SID to assign on error
1311 *
1312 * Obtains a SID associated with the security context that
1313 * has the string representation specified by @scontext.
1314 * The default SID is passed to the MLS layer to be used to allow
1315 * kernel labeling of the MLS field if the MLS field is not present
1316 * (for upgrading to MLS without full relabel).
1317 * Implicitly forces adding of the context even if it cannot be mapped yet.
1318 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1319 * memory is available, or 0 on success.
1320 */
1321 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1322 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1323 {
1324 return security_context_to_sid_core(scontext, scontext_len,
1325 sid, def_sid, gfp_flags, 1);
1326 }
1327
1328 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1329 u32 *sid)
1330 {
1331 return security_context_to_sid_core(scontext, scontext_len,
1332 sid, SECSID_NULL, GFP_KERNEL, 1);
1333 }
1334
1335 static int compute_sid_handle_invalid_context(
1336 struct context *scontext,
1337 struct context *tcontext,
1338 u16 tclass,
1339 struct context *newcontext)
1340 {
1341 char *s = NULL, *t = NULL, *n = NULL;
1342 u32 slen, tlen, nlen;
1343
1344 if (context_struct_to_string(scontext, &s, &slen))
1345 goto out;
1346 if (context_struct_to_string(tcontext, &t, &tlen))
1347 goto out;
1348 if (context_struct_to_string(newcontext, &n, &nlen))
1349 goto out;
1350 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1351 "security_compute_sid: invalid context %s"
1352 " for scontext=%s"
1353 " tcontext=%s"
1354 " tclass=%s",
1355 n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
1356 out:
1357 kfree(s);
1358 kfree(t);
1359 kfree(n);
1360 if (!selinux_enforcing)
1361 return 0;
1362 return -EACCES;
1363 }
1364
1365 static void filename_compute_type(struct policydb *p, struct context *newcontext,
1366 u32 stype, u32 ttype, u16 tclass,
1367 const char *objname)
1368 {
1369 struct filename_trans ft;
1370 struct filename_trans_datum *otype;
1371
1372 /*
1373 * Most filename trans rules are going to live in specific directories
1374 * like /dev or /var/run. This bitmap will quickly skip rule searches
1375 * if the ttype does not contain any rules.
1376 */
1377 if (!ebitmap_get_bit(&p->filename_trans_ttypes, ttype))
1378 return;
1379
1380 ft.stype = stype;
1381 ft.ttype = ttype;
1382 ft.tclass = tclass;
1383 ft.name = objname;
1384
1385 otype = hashtab_search(p->filename_trans, &ft);
1386 if (otype)
1387 newcontext->type = otype->otype;
1388 }
1389
1390 static int security_compute_sid(u32 ssid,
1391 u32 tsid,
1392 u16 orig_tclass,
1393 u32 specified,
1394 const char *objname,
1395 u32 *out_sid,
1396 bool kern)
1397 {
1398 struct class_datum *cladatum = NULL;
1399 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1400 struct role_trans *roletr = NULL;
1401 struct avtab_key avkey;
1402 struct avtab_datum *avdatum;
1403 struct avtab_node *node;
1404 u16 tclass;
1405 int rc = 0;
1406 bool sock;
1407
1408 if (!ss_initialized) {
1409 switch (orig_tclass) {
1410 case SECCLASS_PROCESS: /* kernel value */
1411 *out_sid = ssid;
1412 break;
1413 default:
1414 *out_sid = tsid;
1415 break;
1416 }
1417 goto out;
1418 }
1419
1420 context_init(&newcontext);
1421
1422 read_lock(&policy_rwlock);
1423
1424 if (kern) {
1425 tclass = unmap_class(orig_tclass);
1426 sock = security_is_socket_class(orig_tclass);
1427 } else {
1428 tclass = orig_tclass;
1429 sock = security_is_socket_class(map_class(tclass));
1430 }
1431
1432 scontext = sidtab_search(&sidtab, ssid);
1433 if (!scontext) {
1434 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1435 __func__, ssid);
1436 rc = -EINVAL;
1437 goto out_unlock;
1438 }
1439 tcontext = sidtab_search(&sidtab, tsid);
1440 if (!tcontext) {
1441 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1442 __func__, tsid);
1443 rc = -EINVAL;
1444 goto out_unlock;
1445 }
1446
1447 if (tclass && tclass <= policydb.p_classes.nprim)
1448 cladatum = policydb.class_val_to_struct[tclass - 1];
1449
1450 /* Set the user identity. */
1451 switch (specified) {
1452 case AVTAB_TRANSITION:
1453 case AVTAB_CHANGE:
1454 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1455 newcontext.user = tcontext->user;
1456 } else {
1457 /* notice this gets both DEFAULT_SOURCE and unset */
1458 /* Use the process user identity. */
1459 newcontext.user = scontext->user;
1460 }
1461 break;
1462 case AVTAB_MEMBER:
1463 /* Use the related object owner. */
1464 newcontext.user = tcontext->user;
1465 break;
1466 }
1467
1468 /* Set the role to default values. */
1469 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1470 newcontext.role = scontext->role;
1471 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1472 newcontext.role = tcontext->role;
1473 } else {
1474 if ((tclass == policydb.process_class) || (sock == true))
1475 newcontext.role = scontext->role;
1476 else
1477 newcontext.role = OBJECT_R_VAL;
1478 }
1479
1480 /* Set the type to default values. */
1481 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1482 newcontext.type = scontext->type;
1483 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1484 newcontext.type = tcontext->type;
1485 } else {
1486 if ((tclass == policydb.process_class) || (sock == true)) {
1487 /* Use the type of process. */
1488 newcontext.type = scontext->type;
1489 } else {
1490 /* Use the type of the related object. */
1491 newcontext.type = tcontext->type;
1492 }
1493 }
1494
1495 /* Look for a type transition/member/change rule. */
1496 avkey.source_type = scontext->type;
1497 avkey.target_type = tcontext->type;
1498 avkey.target_class = tclass;
1499 avkey.specified = specified;
1500 avdatum = avtab_search(&policydb.te_avtab, &avkey);
1501
1502 /* If no permanent rule, also check for enabled conditional rules */
1503 if (!avdatum) {
1504 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1505 for (; node; node = avtab_search_node_next(node, specified)) {
1506 if (node->key.specified & AVTAB_ENABLED) {
1507 avdatum = &node->datum;
1508 break;
1509 }
1510 }
1511 }
1512
1513 if (avdatum) {
1514 /* Use the type from the type transition/member/change rule. */
1515 newcontext.type = avdatum->data;
1516 }
1517
1518 /* if we have a objname this is a file trans check so check those rules */
1519 if (objname)
1520 filename_compute_type(&policydb, &newcontext, scontext->type,
1521 tcontext->type, tclass, objname);
1522
1523 /* Check for class-specific changes. */
1524 if (specified & AVTAB_TRANSITION) {
1525 /* Look for a role transition rule. */
1526 for (roletr = policydb.role_tr; roletr; roletr = roletr->next) {
1527 if ((roletr->role == scontext->role) &&
1528 (roletr->type == tcontext->type) &&
1529 (roletr->tclass == tclass)) {
1530 /* Use the role transition rule. */
1531 newcontext.role = roletr->new_role;
1532 break;
1533 }
1534 }
1535 }
1536
1537 /* Set the MLS attributes.
1538 This is done last because it may allocate memory. */
1539 rc = mls_compute_sid(scontext, tcontext, tclass, specified,
1540 &newcontext, sock);
1541 if (rc)
1542 goto out_unlock;
1543
1544 /* Check the validity of the context. */
1545 if (!policydb_context_isvalid(&policydb, &newcontext)) {
1546 rc = compute_sid_handle_invalid_context(scontext,
1547 tcontext,
1548 tclass,
1549 &newcontext);
1550 if (rc)
1551 goto out_unlock;
1552 }
1553 /* Obtain the sid for the context. */
1554 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1555 out_unlock:
1556 read_unlock(&policy_rwlock);
1557 context_destroy(&newcontext);
1558 out:
1559 return rc;
1560 }
1561
1562 /**
1563 * security_transition_sid - Compute the SID for a new subject/object.
1564 * @ssid: source security identifier
1565 * @tsid: target security identifier
1566 * @tclass: target security class
1567 * @out_sid: security identifier for new subject/object
1568 *
1569 * Compute a SID to use for labeling a new subject or object in the
1570 * class @tclass based on a SID pair (@ssid, @tsid).
1571 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1572 * if insufficient memory is available, or %0 if the new SID was
1573 * computed successfully.
1574 */
1575 int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1576 const struct qstr *qstr, u32 *out_sid)
1577 {
1578 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1579 qstr ? qstr->name : NULL, out_sid, true);
1580 }
1581
1582 int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1583 const char *objname, u32 *out_sid)
1584 {
1585 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1586 objname, out_sid, false);
1587 }
1588
1589 /**
1590 * security_member_sid - Compute the SID for member selection.
1591 * @ssid: source security identifier
1592 * @tsid: target security identifier
1593 * @tclass: target security class
1594 * @out_sid: security identifier for selected member
1595 *
1596 * Compute a SID to use when selecting a member of a polyinstantiated
1597 * object of class @tclass based on a SID pair (@ssid, @tsid).
1598 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1599 * if insufficient memory is available, or %0 if the SID was
1600 * computed successfully.
1601 */
1602 int security_member_sid(u32 ssid,
1603 u32 tsid,
1604 u16 tclass,
1605 u32 *out_sid)
1606 {
1607 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL,
1608 out_sid, false);
1609 }
1610
1611 /**
1612 * security_change_sid - Compute the SID for object relabeling.
1613 * @ssid: source security identifier
1614 * @tsid: target security identifier
1615 * @tclass: target security class
1616 * @out_sid: security identifier for selected member
1617 *
1618 * Compute a SID to use for relabeling an object of class @tclass
1619 * based on a SID pair (@ssid, @tsid).
1620 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1621 * if insufficient memory is available, or %0 if the SID was
1622 * computed successfully.
1623 */
1624 int security_change_sid(u32 ssid,
1625 u32 tsid,
1626 u16 tclass,
1627 u32 *out_sid)
1628 {
1629 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1630 out_sid, false);
1631 }
1632
1633 /* Clone the SID into the new SID table. */
1634 static int clone_sid(u32 sid,
1635 struct context *context,
1636 void *arg)
1637 {
1638 struct sidtab *s = arg;
1639
1640 if (sid > SECINITSID_NUM)
1641 return sidtab_insert(s, sid, context);
1642 else
1643 return 0;
1644 }
1645
1646 static inline int convert_context_handle_invalid_context(struct context *context)
1647 {
1648 char *s;
1649 u32 len;
1650
1651 if (selinux_enforcing)
1652 return -EINVAL;
1653
1654 if (!context_struct_to_string(context, &s, &len)) {
1655 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s);
1656 kfree(s);
1657 }
1658 return 0;
1659 }
1660
1661 struct convert_context_args {
1662 struct policydb *oldp;
1663 struct policydb *newp;
1664 };
1665
1666 /*
1667 * Convert the values in the security context
1668 * structure `c' from the values specified
1669 * in the policy `p->oldp' to the values specified
1670 * in the policy `p->newp'. Verify that the
1671 * context is valid under the new policy.
1672 */
1673 static int convert_context(u32 key,
1674 struct context *c,
1675 void *p)
1676 {
1677 struct convert_context_args *args;
1678 struct context oldc;
1679 struct ocontext *oc;
1680 struct mls_range *range;
1681 struct role_datum *role;
1682 struct type_datum *typdatum;
1683 struct user_datum *usrdatum;
1684 char *s;
1685 u32 len;
1686 int rc = 0;
1687
1688 if (key <= SECINITSID_NUM)
1689 goto out;
1690
1691 args = p;
1692
1693 if (c->str) {
1694 struct context ctx;
1695
1696 rc = -ENOMEM;
1697 s = kstrdup(c->str, GFP_KERNEL);
1698 if (!s)
1699 goto out;
1700
1701 rc = string_to_context_struct(args->newp, NULL, s,
1702 c->len, &ctx, SECSID_NULL);
1703 kfree(s);
1704 if (!rc) {
1705 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n",
1706 c->str);
1707 /* Replace string with mapped representation. */
1708 kfree(c->str);
1709 memcpy(c, &ctx, sizeof(*c));
1710 goto out;
1711 } else if (rc == -EINVAL) {
1712 /* Retain string representation for later mapping. */
1713 rc = 0;
1714 goto out;
1715 } else {
1716 /* Other error condition, e.g. ENOMEM. */
1717 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n",
1718 c->str, -rc);
1719 goto out;
1720 }
1721 }
1722
1723 rc = context_cpy(&oldc, c);
1724 if (rc)
1725 goto out;
1726
1727 /* Convert the user. */
1728 rc = -EINVAL;
1729 usrdatum = hashtab_search(args->newp->p_users.table,
1730 sym_name(args->oldp, SYM_USERS, c->user - 1));
1731 if (!usrdatum)
1732 goto bad;
1733 c->user = usrdatum->value;
1734
1735 /* Convert the role. */
1736 rc = -EINVAL;
1737 role = hashtab_search(args->newp->p_roles.table,
1738 sym_name(args->oldp, SYM_ROLES, c->role - 1));
1739 if (!role)
1740 goto bad;
1741 c->role = role->value;
1742
1743 /* Convert the type. */
1744 rc = -EINVAL;
1745 typdatum = hashtab_search(args->newp->p_types.table,
1746 sym_name(args->oldp, SYM_TYPES, c->type - 1));
1747 if (!typdatum)
1748 goto bad;
1749 c->type = typdatum->value;
1750
1751 /* Convert the MLS fields if dealing with MLS policies */
1752 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1753 rc = mls_convert_context(args->oldp, args->newp, c);
1754 if (rc)
1755 goto bad;
1756 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1757 /*
1758 * Switching between MLS and non-MLS policy:
1759 * free any storage used by the MLS fields in the
1760 * context for all existing entries in the sidtab.
1761 */
1762 mls_context_destroy(c);
1763 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1764 /*
1765 * Switching between non-MLS and MLS policy:
1766 * ensure that the MLS fields of the context for all
1767 * existing entries in the sidtab are filled in with a
1768 * suitable default value, likely taken from one of the
1769 * initial SIDs.
1770 */
1771 oc = args->newp->ocontexts[OCON_ISID];
1772 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1773 oc = oc->next;
1774 rc = -EINVAL;
1775 if (!oc) {
1776 printk(KERN_ERR "SELinux: unable to look up"
1777 " the initial SIDs list\n");
1778 goto bad;
1779 }
1780 range = &oc->context[0].range;
1781 rc = mls_range_set(c, range);
1782 if (rc)
1783 goto bad;
1784 }
1785
1786 /* Check the validity of the new context. */
1787 if (!policydb_context_isvalid(args->newp, c)) {
1788 rc = convert_context_handle_invalid_context(&oldc);
1789 if (rc)
1790 goto bad;
1791 }
1792
1793 context_destroy(&oldc);
1794
1795 rc = 0;
1796 out:
1797 return rc;
1798 bad:
1799 /* Map old representation to string and save it. */
1800 rc = context_struct_to_string(&oldc, &s, &len);
1801 if (rc)
1802 return rc;
1803 context_destroy(&oldc);
1804 context_destroy(c);
1805 c->str = s;
1806 c->len = len;
1807 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n",
1808 c->str);
1809 rc = 0;
1810 goto out;
1811 }
1812
1813 static void security_load_policycaps(void)
1814 {
1815 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1816 POLICYDB_CAPABILITY_NETPEER);
1817 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1818 POLICYDB_CAPABILITY_OPENPERM);
1819 }
1820
1821 static int security_preserve_bools(struct policydb *p);
1822
1823 /**
1824 * security_load_policy - Load a security policy configuration.
1825 * @data: binary policy data
1826 * @len: length of data in bytes
1827 *
1828 * Load a new set of security policy configuration data,
1829 * validate it and convert the SID table as necessary.
1830 * This function will flush the access vector cache after
1831 * loading the new policy.
1832 */
1833 int security_load_policy(void *data, size_t len)
1834 {
1835 struct policydb oldpolicydb, newpolicydb;
1836 struct sidtab oldsidtab, newsidtab;
1837 struct selinux_mapping *oldmap, *map = NULL;
1838 struct convert_context_args args;
1839 u32 seqno;
1840 u16 map_size;
1841 int rc = 0;
1842 struct policy_file file = { data, len }, *fp = &file;
1843
1844 if (!ss_initialized) {
1845 avtab_cache_init();
1846 rc = policydb_read(&policydb, fp);
1847 if (rc) {
1848 avtab_cache_destroy();
1849 return rc;
1850 }
1851
1852 policydb.len = len;
1853 rc = selinux_set_mapping(&policydb, secclass_map,
1854 &current_mapping,
1855 &current_mapping_size);
1856 if (rc) {
1857 policydb_destroy(&policydb);
1858 avtab_cache_destroy();
1859 return rc;
1860 }
1861
1862 rc = policydb_load_isids(&policydb, &sidtab);
1863 if (rc) {
1864 policydb_destroy(&policydb);
1865 avtab_cache_destroy();
1866 return rc;
1867 }
1868
1869 security_load_policycaps();
1870 ss_initialized = 1;
1871 seqno = ++latest_granting;
1872 selinux_complete_init();
1873 avc_ss_reset(seqno);
1874 selnl_notify_policyload(seqno);
1875 selinux_status_update_policyload(seqno);
1876 selinux_netlbl_cache_invalidate();
1877 selinux_xfrm_notify_policyload();
1878 return 0;
1879 }
1880
1881 #if 0
1882 sidtab_hash_eval(&sidtab, "sids");
1883 #endif
1884
1885 rc = policydb_read(&newpolicydb, fp);
1886 if (rc)
1887 return rc;
1888
1889 newpolicydb.len = len;
1890 /* If switching between different policy types, log MLS status */
1891 if (policydb.mls_enabled && !newpolicydb.mls_enabled)
1892 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
1893 else if (!policydb.mls_enabled && newpolicydb.mls_enabled)
1894 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
1895
1896 rc = policydb_load_isids(&newpolicydb, &newsidtab);
1897 if (rc) {
1898 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
1899 policydb_destroy(&newpolicydb);
1900 return rc;
1901 }
1902
1903 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size);
1904 if (rc)
1905 goto err;
1906
1907 rc = security_preserve_bools(&newpolicydb);
1908 if (rc) {
1909 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
1910 goto err;
1911 }
1912
1913 /* Clone the SID table. */
1914 sidtab_shutdown(&sidtab);
1915
1916 rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
1917 if (rc)
1918 goto err;
1919
1920 /*
1921 * Convert the internal representations of contexts
1922 * in the new SID table.
1923 */
1924 args.oldp = &policydb;
1925 args.newp = &newpolicydb;
1926 rc = sidtab_map(&newsidtab, convert_context, &args);
1927 if (rc) {
1928 printk(KERN_ERR "SELinux: unable to convert the internal"
1929 " representation of contexts in the new SID"
1930 " table\n");
1931 goto err;
1932 }
1933
1934 /* Save the old policydb and SID table to free later. */
1935 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1936 sidtab_set(&oldsidtab, &sidtab);
1937
1938 /* Install the new policydb and SID table. */
1939 write_lock_irq(&policy_rwlock);
1940 memcpy(&policydb, &newpolicydb, sizeof policydb);
1941 sidtab_set(&sidtab, &newsidtab);
1942 security_load_policycaps();
1943 oldmap = current_mapping;
1944 current_mapping = map;
1945 current_mapping_size = map_size;
1946 seqno = ++latest_granting;
1947 write_unlock_irq(&policy_rwlock);
1948
1949 /* Free the old policydb and SID table. */
1950 policydb_destroy(&oldpolicydb);
1951 sidtab_destroy(&oldsidtab);
1952 kfree(oldmap);
1953
1954 avc_ss_reset(seqno);
1955 selnl_notify_policyload(seqno);
1956 selinux_status_update_policyload(seqno);
1957 selinux_netlbl_cache_invalidate();
1958 selinux_xfrm_notify_policyload();
1959
1960 return 0;
1961
1962 err:
1963 kfree(map);
1964 sidtab_destroy(&newsidtab);
1965 policydb_destroy(&newpolicydb);
1966 return rc;
1967
1968 }
1969
1970 size_t security_policydb_len(void)
1971 {
1972 size_t len;
1973
1974 read_lock(&policy_rwlock);
1975 len = policydb.len;
1976 read_unlock(&policy_rwlock);
1977
1978 return len;
1979 }
1980
1981 /**
1982 * security_port_sid - Obtain the SID for a port.
1983 * @protocol: protocol number
1984 * @port: port number
1985 * @out_sid: security identifier
1986 */
1987 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1988 {
1989 struct ocontext *c;
1990 int rc = 0;
1991
1992 read_lock(&policy_rwlock);
1993
1994 c = policydb.ocontexts[OCON_PORT];
1995 while (c) {
1996 if (c->u.port.protocol == protocol &&
1997 c->u.port.low_port <= port &&
1998 c->u.port.high_port >= port)
1999 break;
2000 c = c->next;
2001 }
2002
2003 if (c) {
2004 if (!c->sid[0]) {
2005 rc = sidtab_context_to_sid(&sidtab,
2006 &c->context[0],
2007 &c->sid[0]);
2008 if (rc)
2009 goto out;
2010 }
2011 *out_sid = c->sid[0];
2012 } else {
2013 *out_sid = SECINITSID_PORT;
2014 }
2015
2016 out:
2017 read_unlock(&policy_rwlock);
2018 return rc;
2019 }
2020
2021 /**
2022 * security_netif_sid - Obtain the SID for a network interface.
2023 * @name: interface name
2024 * @if_sid: interface SID
2025 */
2026 int security_netif_sid(char *name, u32 *if_sid)
2027 {
2028 int rc = 0;
2029 struct ocontext *c;
2030
2031 read_lock(&policy_rwlock);
2032
2033 c = policydb.ocontexts[OCON_NETIF];
2034 while (c) {
2035 if (strcmp(name, c->u.name) == 0)
2036 break;
2037 c = c->next;
2038 }
2039
2040 if (c) {
2041 if (!c->sid[0] || !c->sid[1]) {
2042 rc = sidtab_context_to_sid(&sidtab,
2043 &c->context[0],
2044 &c->sid[0]);
2045 if (rc)
2046 goto out;
2047 rc = sidtab_context_to_sid(&sidtab,
2048 &c->context[1],
2049 &c->sid[1]);
2050 if (rc)
2051 goto out;
2052 }
2053 *if_sid = c->sid[0];
2054 } else
2055 *if_sid = SECINITSID_NETIF;
2056
2057 out:
2058 read_unlock(&policy_rwlock);
2059 return rc;
2060 }
2061
2062 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2063 {
2064 int i, fail = 0;
2065
2066 for (i = 0; i < 4; i++)
2067 if (addr[i] != (input[i] & mask[i])) {
2068 fail = 1;
2069 break;
2070 }
2071
2072 return !fail;
2073 }
2074
2075 /**
2076 * security_node_sid - Obtain the SID for a node (host).
2077 * @domain: communication domain aka address family
2078 * @addrp: address
2079 * @addrlen: address length in bytes
2080 * @out_sid: security identifier
2081 */
2082 int security_node_sid(u16 domain,
2083 void *addrp,
2084 u32 addrlen,
2085 u32 *out_sid)
2086 {
2087 int rc;
2088 struct ocontext *c;
2089
2090 read_lock(&policy_rwlock);
2091
2092 switch (domain) {
2093 case AF_INET: {
2094 u32 addr;
2095
2096 rc = -EINVAL;
2097 if (addrlen != sizeof(u32))
2098 goto out;
2099
2100 addr = *((u32 *)addrp);
2101
2102 c = policydb.ocontexts[OCON_NODE];
2103 while (c) {
2104 if (c->u.node.addr == (addr & c->u.node.mask))
2105 break;
2106 c = c->next;
2107 }
2108 break;
2109 }
2110
2111 case AF_INET6:
2112 rc = -EINVAL;
2113 if (addrlen != sizeof(u64) * 2)
2114 goto out;
2115 c = policydb.ocontexts[OCON_NODE6];
2116 while (c) {
2117 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2118 c->u.node6.mask))
2119 break;
2120 c = c->next;
2121 }
2122 break;
2123
2124 default:
2125 rc = 0;
2126 *out_sid = SECINITSID_NODE;
2127 goto out;
2128 }
2129
2130 if (c) {
2131 if (!c->sid[0]) {
2132 rc = sidtab_context_to_sid(&sidtab,
2133 &c->context[0],
2134 &c->sid[0]);
2135 if (rc)
2136 goto out;
2137 }
2138 *out_sid = c->sid[0];
2139 } else {
2140 *out_sid = SECINITSID_NODE;
2141 }
2142
2143 rc = 0;
2144 out:
2145 read_unlock(&policy_rwlock);
2146 return rc;
2147 }
2148
2149 #define SIDS_NEL 25
2150
2151 /**
2152 * security_get_user_sids - Obtain reachable SIDs for a user.
2153 * @fromsid: starting SID
2154 * @username: username
2155 * @sids: array of reachable SIDs for user
2156 * @nel: number of elements in @sids
2157 *
2158 * Generate the set of SIDs for legal security contexts
2159 * for a given user that can be reached by @fromsid.
2160 * Set *@sids to point to a dynamically allocated
2161 * array containing the set of SIDs. Set *@nel to the
2162 * number of elements in the array.
2163 */
2164
2165 int security_get_user_sids(u32 fromsid,
2166 char *username,
2167 u32 **sids,
2168 u32 *nel)
2169 {
2170 struct context *fromcon, usercon;
2171 u32 *mysids = NULL, *mysids2, sid;
2172 u32 mynel = 0, maxnel = SIDS_NEL;
2173 struct user_datum *user;
2174 struct role_datum *role;
2175 struct ebitmap_node *rnode, *tnode;
2176 int rc = 0, i, j;
2177
2178 *sids = NULL;
2179 *nel = 0;
2180
2181 if (!ss_initialized)
2182 goto out;
2183
2184 read_lock(&policy_rwlock);
2185
2186 context_init(&usercon);
2187
2188 rc = -EINVAL;
2189 fromcon = sidtab_search(&sidtab, fromsid);
2190 if (!fromcon)
2191 goto out_unlock;
2192
2193 rc = -EINVAL;
2194 user = hashtab_search(policydb.p_users.table, username);
2195 if (!user)
2196 goto out_unlock;
2197
2198 usercon.user = user->value;
2199
2200 rc = -ENOMEM;
2201 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2202 if (!mysids)
2203 goto out_unlock;
2204
2205 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2206 role = policydb.role_val_to_struct[i];
2207 usercon.role = i + 1;
2208 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2209 usercon.type = j + 1;
2210
2211 if (mls_setup_user_range(fromcon, user, &usercon))
2212 continue;
2213
2214 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2215 if (rc)
2216 goto out_unlock;
2217 if (mynel < maxnel) {
2218 mysids[mynel++] = sid;
2219 } else {
2220 rc = -ENOMEM;
2221 maxnel += SIDS_NEL;
2222 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2223 if (!mysids2)
2224 goto out_unlock;
2225 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2226 kfree(mysids);
2227 mysids = mysids2;
2228 mysids[mynel++] = sid;
2229 }
2230 }
2231 }
2232 rc = 0;
2233 out_unlock:
2234 read_unlock(&policy_rwlock);
2235 if (rc || !mynel) {
2236 kfree(mysids);
2237 goto out;
2238 }
2239
2240 rc = -ENOMEM;
2241 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2242 if (!mysids2) {
2243 kfree(mysids);
2244 goto out;
2245 }
2246 for (i = 0, j = 0; i < mynel; i++) {
2247 struct av_decision dummy_avd;
2248 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2249 SECCLASS_PROCESS, /* kernel value */
2250 PROCESS__TRANSITION, AVC_STRICT,
2251 &dummy_avd);
2252 if (!rc)
2253 mysids2[j++] = mysids[i];
2254 cond_resched();
2255 }
2256 rc = 0;
2257 kfree(mysids);
2258 *sids = mysids2;
2259 *nel = j;
2260 out:
2261 return rc;
2262 }
2263
2264 /**
2265 * security_genfs_sid - Obtain a SID for a file in a filesystem
2266 * @fstype: filesystem type
2267 * @path: path from root of mount
2268 * @sclass: file security class
2269 * @sid: SID for path
2270 *
2271 * Obtain a SID to use for a file in a filesystem that
2272 * cannot support xattr or use a fixed labeling behavior like
2273 * transition SIDs or task SIDs.
2274 */
2275 int security_genfs_sid(const char *fstype,
2276 char *path,
2277 u16 orig_sclass,
2278 u32 *sid)
2279 {
2280 int len;
2281 u16 sclass;
2282 struct genfs *genfs;
2283 struct ocontext *c;
2284 int rc, cmp = 0;
2285
2286 while (path[0] == '/' && path[1] == '/')
2287 path++;
2288
2289 read_lock(&policy_rwlock);
2290
2291 sclass = unmap_class(orig_sclass);
2292 *sid = SECINITSID_UNLABELED;
2293
2294 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2295 cmp = strcmp(fstype, genfs->fstype);
2296 if (cmp <= 0)
2297 break;
2298 }
2299
2300 rc = -ENOENT;
2301 if (!genfs || cmp)
2302 goto out;
2303
2304 for (c = genfs->head; c; c = c->next) {
2305 len = strlen(c->u.name);
2306 if ((!c->v.sclass || sclass == c->v.sclass) &&
2307 (strncmp(c->u.name, path, len) == 0))
2308 break;
2309 }
2310
2311 rc = -ENOENT;
2312 if (!c)
2313 goto out;
2314
2315 if (!c->sid[0]) {
2316 rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]);
2317 if (rc)
2318 goto out;
2319 }
2320
2321 *sid = c->sid[0];
2322 rc = 0;
2323 out:
2324 read_unlock(&policy_rwlock);
2325 return rc;
2326 }
2327
2328 /**
2329 * security_fs_use - Determine how to handle labeling for a filesystem.
2330 * @fstype: filesystem type
2331 * @behavior: labeling behavior
2332 * @sid: SID for filesystem (superblock)
2333 */
2334 int security_fs_use(
2335 const char *fstype,
2336 unsigned int *behavior,
2337 u32 *sid)
2338 {
2339 int rc = 0;
2340 struct ocontext *c;
2341
2342 read_lock(&policy_rwlock);
2343
2344 c = policydb.ocontexts[OCON_FSUSE];
2345 while (c) {
2346 if (strcmp(fstype, c->u.name) == 0)
2347 break;
2348 c = c->next;
2349 }
2350
2351 if (c) {
2352 *behavior = c->v.behavior;
2353 if (!c->sid[0]) {
2354 rc = sidtab_context_to_sid(&sidtab, &c->context[0],
2355 &c->sid[0]);
2356 if (rc)
2357 goto out;
2358 }
2359 *sid = c->sid[0];
2360 } else {
2361 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
2362 if (rc) {
2363 *behavior = SECURITY_FS_USE_NONE;
2364 rc = 0;
2365 } else {
2366 *behavior = SECURITY_FS_USE_GENFS;
2367 }
2368 }
2369
2370 out:
2371 read_unlock(&policy_rwlock);
2372 return rc;
2373 }
2374
2375 int security_get_bools(int *len, char ***names, int **values)
2376 {
2377 int i, rc;
2378
2379 read_lock(&policy_rwlock);
2380 *names = NULL;
2381 *values = NULL;
2382
2383 rc = 0;
2384 *len = policydb.p_bools.nprim;
2385 if (!*len)
2386 goto out;
2387
2388 rc = -ENOMEM;
2389 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2390 if (!*names)
2391 goto err;
2392
2393 rc = -ENOMEM;
2394 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2395 if (!*values)
2396 goto err;
2397
2398 for (i = 0; i < *len; i++) {
2399 size_t name_len;
2400
2401 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2402 name_len = strlen(sym_name(&policydb, SYM_BOOLS, i)) + 1;
2403
2404 rc = -ENOMEM;
2405 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
2406 if (!(*names)[i])
2407 goto err;
2408
2409 strncpy((*names)[i], sym_name(&policydb, SYM_BOOLS, i), name_len);
2410 (*names)[i][name_len - 1] = 0;
2411 }
2412 rc = 0;
2413 out:
2414 read_unlock(&policy_rwlock);
2415 return rc;
2416 err:
2417 if (*names) {
2418 for (i = 0; i < *len; i++)
2419 kfree((*names)[i]);
2420 }
2421 kfree(*values);
2422 goto out;
2423 }
2424
2425
2426 int security_set_bools(int len, int *values)
2427 {
2428 int i, rc;
2429 int lenp, seqno = 0;
2430 struct cond_node *cur;
2431
2432 write_lock_irq(&policy_rwlock);
2433
2434 rc = -EFAULT;
2435 lenp = policydb.p_bools.nprim;
2436 if (len != lenp)
2437 goto out;
2438
2439 for (i = 0; i < len; i++) {
2440 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2441 audit_log(current->audit_context, GFP_ATOMIC,
2442 AUDIT_MAC_CONFIG_CHANGE,
2443 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2444 sym_name(&policydb, SYM_BOOLS, i),
2445 !!values[i],
2446 policydb.bool_val_to_struct[i]->state,
2447 from_kuid(&init_user_ns, audit_get_loginuid(current)),
2448 audit_get_sessionid(current));
2449 }
2450 if (values[i])
2451 policydb.bool_val_to_struct[i]->state = 1;
2452 else
2453 policydb.bool_val_to_struct[i]->state = 0;
2454 }
2455
2456 for (cur = policydb.cond_list; cur; cur = cur->next) {
2457 rc = evaluate_cond_node(&policydb, cur);
2458 if (rc)
2459 goto out;
2460 }
2461
2462 seqno = ++latest_granting;
2463 rc = 0;
2464 out:
2465 write_unlock_irq(&policy_rwlock);
2466 if (!rc) {
2467 avc_ss_reset(seqno);
2468 selnl_notify_policyload(seqno);
2469 selinux_status_update_policyload(seqno);
2470 selinux_xfrm_notify_policyload();
2471 }
2472 return rc;
2473 }
2474
2475 int security_get_bool_value(int bool)
2476 {
2477 int rc;
2478 int len;
2479
2480 read_lock(&policy_rwlock);
2481
2482 rc = -EFAULT;
2483 len = policydb.p_bools.nprim;
2484 if (bool >= len)
2485 goto out;
2486
2487 rc = policydb.bool_val_to_struct[bool]->state;
2488 out:
2489 read_unlock(&policy_rwlock);
2490 return rc;
2491 }
2492
2493 static int security_preserve_bools(struct policydb *p)
2494 {
2495 int rc, nbools = 0, *bvalues = NULL, i;
2496 char **bnames = NULL;
2497 struct cond_bool_datum *booldatum;
2498 struct cond_node *cur;
2499
2500 rc = security_get_bools(&nbools, &bnames, &bvalues);
2501 if (rc)
2502 goto out;
2503 for (i = 0; i < nbools; i++) {
2504 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2505 if (booldatum)
2506 booldatum->state = bvalues[i];
2507 }
2508 for (cur = p->cond_list; cur; cur = cur->next) {
2509 rc = evaluate_cond_node(p, cur);
2510 if (rc)
2511 goto out;
2512 }
2513
2514 out:
2515 if (bnames) {
2516 for (i = 0; i < nbools; i++)
2517 kfree(bnames[i]);
2518 }
2519 kfree(bnames);
2520 kfree(bvalues);
2521 return rc;
2522 }
2523
2524 /*
2525 * security_sid_mls_copy() - computes a new sid based on the given
2526 * sid and the mls portion of mls_sid.
2527 */
2528 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2529 {
2530 struct context *context1;
2531 struct context *context2;
2532 struct context newcon;
2533 char *s;
2534 u32 len;
2535 int rc;
2536
2537 rc = 0;
2538 if (!ss_initialized || !policydb.mls_enabled) {
2539 *new_sid = sid;
2540 goto out;
2541 }
2542
2543 context_init(&newcon);
2544
2545 read_lock(&policy_rwlock);
2546
2547 rc = -EINVAL;
2548 context1 = sidtab_search(&sidtab, sid);
2549 if (!context1) {
2550 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2551 __func__, sid);
2552 goto out_unlock;
2553 }
2554
2555 rc = -EINVAL;
2556 context2 = sidtab_search(&sidtab, mls_sid);
2557 if (!context2) {
2558 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2559 __func__, mls_sid);
2560 goto out_unlock;
2561 }
2562
2563 newcon.user = context1->user;
2564 newcon.role = context1->role;
2565 newcon.type = context1->type;
2566 rc = mls_context_cpy(&newcon, context2);
2567 if (rc)
2568 goto out_unlock;
2569
2570 /* Check the validity of the new context. */
2571 if (!policydb_context_isvalid(&policydb, &newcon)) {
2572 rc = convert_context_handle_invalid_context(&newcon);
2573 if (rc) {
2574 if (!context_struct_to_string(&newcon, &s, &len)) {
2575 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2576 "security_sid_mls_copy: invalid context %s", s);
2577 kfree(s);
2578 }
2579 goto out_unlock;
2580 }
2581 }
2582
2583 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2584 out_unlock:
2585 read_unlock(&policy_rwlock);
2586 context_destroy(&newcon);
2587 out:
2588 return rc;
2589 }
2590
2591 /**
2592 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2593 * @nlbl_sid: NetLabel SID
2594 * @nlbl_type: NetLabel labeling protocol type
2595 * @xfrm_sid: XFRM SID
2596 *
2597 * Description:
2598 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2599 * resolved into a single SID it is returned via @peer_sid and the function
2600 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
2601 * returns a negative value. A table summarizing the behavior is below:
2602 *
2603 * | function return | @sid
2604 * ------------------------------+-----------------+-----------------
2605 * no peer labels | 0 | SECSID_NULL
2606 * single peer label | 0 | <peer_label>
2607 * multiple, consistent labels | 0 | <peer_label>
2608 * multiple, inconsistent labels | -<errno> | SECSID_NULL
2609 *
2610 */
2611 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2612 u32 xfrm_sid,
2613 u32 *peer_sid)
2614 {
2615 int rc;
2616 struct context *nlbl_ctx;
2617 struct context *xfrm_ctx;
2618
2619 *peer_sid = SECSID_NULL;
2620
2621 /* handle the common (which also happens to be the set of easy) cases
2622 * right away, these two if statements catch everything involving a
2623 * single or absent peer SID/label */
2624 if (xfrm_sid == SECSID_NULL) {
2625 *peer_sid = nlbl_sid;
2626 return 0;
2627 }
2628 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2629 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2630 * is present */
2631 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2632 *peer_sid = xfrm_sid;
2633 return 0;
2634 }
2635
2636 /* we don't need to check ss_initialized here since the only way both
2637 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2638 * security server was initialized and ss_initialized was true */
2639 if (!policydb.mls_enabled)
2640 return 0;
2641
2642 read_lock(&policy_rwlock);
2643
2644 rc = -EINVAL;
2645 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2646 if (!nlbl_ctx) {
2647 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2648 __func__, nlbl_sid);
2649 goto out;
2650 }
2651 rc = -EINVAL;
2652 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2653 if (!xfrm_ctx) {
2654 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2655 __func__, xfrm_sid);
2656 goto out;
2657 }
2658 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2659 if (rc)
2660 goto out;
2661
2662 /* at present NetLabel SIDs/labels really only carry MLS
2663 * information so if the MLS portion of the NetLabel SID
2664 * matches the MLS portion of the labeled XFRM SID/label
2665 * then pass along the XFRM SID as it is the most
2666 * expressive */
2667 *peer_sid = xfrm_sid;
2668 out:
2669 read_unlock(&policy_rwlock);
2670 return rc;
2671 }
2672
2673 static int get_classes_callback(void *k, void *d, void *args)
2674 {
2675 struct class_datum *datum = d;
2676 char *name = k, **classes = args;
2677 int value = datum->value - 1;
2678
2679 classes[value] = kstrdup(name, GFP_ATOMIC);
2680 if (!classes[value])
2681 return -ENOMEM;
2682
2683 return 0;
2684 }
2685
2686 int security_get_classes(char ***classes, int *nclasses)
2687 {
2688 int rc;
2689
2690 read_lock(&policy_rwlock);
2691
2692 rc = -ENOMEM;
2693 *nclasses = policydb.p_classes.nprim;
2694 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
2695 if (!*classes)
2696 goto out;
2697
2698 rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2699 *classes);
2700 if (rc) {
2701 int i;
2702 for (i = 0; i < *nclasses; i++)
2703 kfree((*classes)[i]);
2704 kfree(*classes);
2705 }
2706
2707 out:
2708 read_unlock(&policy_rwlock);
2709 return rc;
2710 }
2711
2712 static int get_permissions_callback(void *k, void *d, void *args)
2713 {
2714 struct perm_datum *datum = d;
2715 char *name = k, **perms = args;
2716 int value = datum->value - 1;
2717
2718 perms[value] = kstrdup(name, GFP_ATOMIC);
2719 if (!perms[value])
2720 return -ENOMEM;
2721
2722 return 0;
2723 }
2724
2725 int security_get_permissions(char *class, char ***perms, int *nperms)
2726 {
2727 int rc, i;
2728 struct class_datum *match;
2729
2730 read_lock(&policy_rwlock);
2731
2732 rc = -EINVAL;
2733 match = hashtab_search(policydb.p_classes.table, class);
2734 if (!match) {
2735 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
2736 __func__, class);
2737 goto out;
2738 }
2739
2740 rc = -ENOMEM;
2741 *nperms = match->permissions.nprim;
2742 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
2743 if (!*perms)
2744 goto out;
2745
2746 if (match->comdatum) {
2747 rc = hashtab_map(match->comdatum->permissions.table,
2748 get_permissions_callback, *perms);
2749 if (rc)
2750 goto err;
2751 }
2752
2753 rc = hashtab_map(match->permissions.table, get_permissions_callback,
2754 *perms);
2755 if (rc)
2756 goto err;
2757
2758 out:
2759 read_unlock(&policy_rwlock);
2760 return rc;
2761
2762 err:
2763 read_unlock(&policy_rwlock);
2764 for (i = 0; i < *nperms; i++)
2765 kfree((*perms)[i]);
2766 kfree(*perms);
2767 return rc;
2768 }
2769
2770 int security_get_reject_unknown(void)
2771 {
2772 return policydb.reject_unknown;
2773 }
2774
2775 int security_get_allow_unknown(void)
2776 {
2777 return policydb.allow_unknown;
2778 }
2779
2780 /**
2781 * security_policycap_supported - Check for a specific policy capability
2782 * @req_cap: capability
2783 *
2784 * Description:
2785 * This function queries the currently loaded policy to see if it supports the
2786 * capability specified by @req_cap. Returns true (1) if the capability is
2787 * supported, false (0) if it isn't supported.
2788 *
2789 */
2790 int security_policycap_supported(unsigned int req_cap)
2791 {
2792 int rc;
2793
2794 read_lock(&policy_rwlock);
2795 rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2796 read_unlock(&policy_rwlock);
2797
2798 return rc;
2799 }
2800
2801 struct selinux_audit_rule {
2802 u32 au_seqno;
2803 struct context au_ctxt;
2804 };
2805
2806 void selinux_audit_rule_free(void *vrule)
2807 {
2808 struct selinux_audit_rule *rule = vrule;
2809
2810 if (rule) {
2811 context_destroy(&rule->au_ctxt);
2812 kfree(rule);
2813 }
2814 }
2815
2816 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2817 {
2818 struct selinux_audit_rule *tmprule;
2819 struct role_datum *roledatum;
2820 struct type_datum *typedatum;
2821 struct user_datum *userdatum;
2822 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2823 int rc = 0;
2824
2825 *rule = NULL;
2826
2827 if (!ss_initialized)
2828 return -EOPNOTSUPP;
2829
2830 switch (field) {
2831 case AUDIT_SUBJ_USER:
2832 case AUDIT_SUBJ_ROLE:
2833 case AUDIT_SUBJ_TYPE:
2834 case AUDIT_OBJ_USER:
2835 case AUDIT_OBJ_ROLE:
2836 case AUDIT_OBJ_TYPE:
2837 /* only 'equals' and 'not equals' fit user, role, and type */
2838 if (op != Audit_equal && op != Audit_not_equal)
2839 return -EINVAL;
2840 break;
2841 case AUDIT_SUBJ_SEN:
2842 case AUDIT_SUBJ_CLR:
2843 case AUDIT_OBJ_LEV_LOW:
2844 case AUDIT_OBJ_LEV_HIGH:
2845 /* we do not allow a range, indicated by the presence of '-' */
2846 if (strchr(rulestr, '-'))
2847 return -EINVAL;
2848 break;
2849 default:
2850 /* only the above fields are valid */
2851 return -EINVAL;
2852 }
2853
2854 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2855 if (!tmprule)
2856 return -ENOMEM;
2857
2858 context_init(&tmprule->au_ctxt);
2859
2860 read_lock(&policy_rwlock);
2861
2862 tmprule->au_seqno = latest_granting;
2863
2864 switch (field) {
2865 case AUDIT_SUBJ_USER:
2866 case AUDIT_OBJ_USER:
2867 rc = -EINVAL;
2868 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2869 if (!userdatum)
2870 goto out;
2871 tmprule->au_ctxt.user = userdatum->value;
2872 break;
2873 case AUDIT_SUBJ_ROLE:
2874 case AUDIT_OBJ_ROLE:
2875 rc = -EINVAL;
2876 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2877 if (!roledatum)
2878 goto out;
2879 tmprule->au_ctxt.role = roledatum->value;
2880 break;
2881 case AUDIT_SUBJ_TYPE:
2882 case AUDIT_OBJ_TYPE:
2883 rc = -EINVAL;
2884 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2885 if (!typedatum)
2886 goto out;
2887 tmprule->au_ctxt.type = typedatum->value;
2888 break;
2889 case AUDIT_SUBJ_SEN:
2890 case AUDIT_SUBJ_CLR:
2891 case AUDIT_OBJ_LEV_LOW:
2892 case AUDIT_OBJ_LEV_HIGH:
2893 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2894 if (rc)
2895 goto out;
2896 break;
2897 }
2898 rc = 0;
2899 out:
2900 read_unlock(&policy_rwlock);
2901
2902 if (rc) {
2903 selinux_audit_rule_free(tmprule);
2904 tmprule = NULL;
2905 }
2906
2907 *rule = tmprule;
2908
2909 return rc;
2910 }
2911
2912 /* Check to see if the rule contains any selinux fields */
2913 int selinux_audit_rule_known(struct audit_krule *rule)
2914 {
2915 int i;
2916
2917 for (i = 0; i < rule->field_count; i++) {
2918 struct audit_field *f = &rule->fields[i];
2919 switch (f->type) {
2920 case AUDIT_SUBJ_USER:
2921 case AUDIT_SUBJ_ROLE:
2922 case AUDIT_SUBJ_TYPE:
2923 case AUDIT_SUBJ_SEN:
2924 case AUDIT_SUBJ_CLR:
2925 case AUDIT_OBJ_USER:
2926 case AUDIT_OBJ_ROLE:
2927 case AUDIT_OBJ_TYPE:
2928 case AUDIT_OBJ_LEV_LOW:
2929 case AUDIT_OBJ_LEV_HIGH:
2930 return 1;
2931 }
2932 }
2933
2934 return 0;
2935 }
2936
2937 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2938 struct audit_context *actx)
2939 {
2940 struct context *ctxt;
2941 struct mls_level *level;
2942 struct selinux_audit_rule *rule = vrule;
2943 int match = 0;
2944
2945 if (!rule) {
2946 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2947 "selinux_audit_rule_match: missing rule\n");
2948 return -ENOENT;
2949 }
2950
2951 read_lock(&policy_rwlock);
2952
2953 if (rule->au_seqno < latest_granting) {
2954 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2955 "selinux_audit_rule_match: stale rule\n");
2956 match = -ESTALE;
2957 goto out;
2958 }
2959
2960 ctxt = sidtab_search(&sidtab, sid);
2961 if (!ctxt) {
2962 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2963 "selinux_audit_rule_match: unrecognized SID %d\n",
2964 sid);
2965 match = -ENOENT;
2966 goto out;
2967 }
2968
2969 /* a field/op pair that is not caught here will simply fall through
2970 without a match */
2971 switch (field) {
2972 case AUDIT_SUBJ_USER:
2973 case AUDIT_OBJ_USER:
2974 switch (op) {
2975 case Audit_equal:
2976 match = (ctxt->user == rule->au_ctxt.user);
2977 break;
2978 case Audit_not_equal:
2979 match = (ctxt->user != rule->au_ctxt.user);
2980 break;
2981 }
2982 break;
2983 case AUDIT_SUBJ_ROLE:
2984 case AUDIT_OBJ_ROLE:
2985 switch (op) {
2986 case Audit_equal:
2987 match = (ctxt->role == rule->au_ctxt.role);
2988 break;
2989 case Audit_not_equal:
2990 match = (ctxt->role != rule->au_ctxt.role);
2991 break;
2992 }
2993 break;
2994 case AUDIT_SUBJ_TYPE:
2995 case AUDIT_OBJ_TYPE:
2996 switch (op) {
2997 case Audit_equal:
2998 match = (ctxt->type == rule->au_ctxt.type);
2999 break;
3000 case Audit_not_equal:
3001 match = (ctxt->type != rule->au_ctxt.type);
3002 break;
3003 }
3004 break;
3005 case AUDIT_SUBJ_SEN:
3006 case AUDIT_SUBJ_CLR:
3007 case AUDIT_OBJ_LEV_LOW:
3008 case AUDIT_OBJ_LEV_HIGH:
3009 level = ((field == AUDIT_SUBJ_SEN ||
3010 field == AUDIT_OBJ_LEV_LOW) ?
3011 &ctxt->range.level[0] : &ctxt->range.level[1]);
3012 switch (op) {
3013 case Audit_equal:
3014 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3015 level);
3016 break;
3017 case Audit_not_equal:
3018 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3019 level);
3020 break;
3021 case Audit_lt:
3022 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3023 level) &&
3024 !mls_level_eq(&rule->au_ctxt.range.level[0],
3025 level));
3026 break;
3027 case Audit_le:
3028 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3029 level);
3030 break;
3031 case Audit_gt:
3032 match = (mls_level_dom(level,
3033 &rule->au_ctxt.range.level[0]) &&
3034 !mls_level_eq(level,
3035 &rule->au_ctxt.range.level[0]));
3036 break;
3037 case Audit_ge:
3038 match = mls_level_dom(level,
3039 &rule->au_ctxt.range.level[0]);
3040 break;
3041 }
3042 }
3043
3044 out:
3045 read_unlock(&policy_rwlock);
3046 return match;
3047 }
3048
3049 static int (*aurule_callback)(void) = audit_update_lsm_rules;
3050
3051 static int aurule_avc_callback(u32 event)
3052 {
3053 int err = 0;
3054
3055 if (event == AVC_CALLBACK_RESET && aurule_callback)
3056 err = aurule_callback();
3057 return err;
3058 }
3059
3060 static int __init aurule_init(void)
3061 {
3062 int err;
3063
3064 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3065 if (err)
3066 panic("avc_add_callback() failed, error %d\n", err);
3067
3068 return err;
3069 }
3070 __initcall(aurule_init);
3071
3072 #ifdef CONFIG_NETLABEL
3073 /**
3074 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3075 * @secattr: the NetLabel packet security attributes
3076 * @sid: the SELinux SID
3077 *
3078 * Description:
3079 * Attempt to cache the context in @ctx, which was derived from the packet in
3080 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3081 * already been initialized.
3082 *
3083 */
3084 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3085 u32 sid)
3086 {
3087 u32 *sid_cache;
3088
3089 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3090 if (sid_cache == NULL)
3091 return;
3092 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3093 if (secattr->cache == NULL) {
3094 kfree(sid_cache);
3095 return;
3096 }
3097
3098 *sid_cache = sid;
3099 secattr->cache->free = kfree;
3100 secattr->cache->data = sid_cache;
3101 secattr->flags |= NETLBL_SECATTR_CACHE;
3102 }
3103
3104 /**
3105 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3106 * @secattr: the NetLabel packet security attributes
3107 * @sid: the SELinux SID
3108 *
3109 * Description:
3110 * Convert the given NetLabel security attributes in @secattr into a
3111 * SELinux SID. If the @secattr field does not contain a full SELinux
3112 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3113 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3114 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3115 * conversion for future lookups. Returns zero on success, negative values on
3116 * failure.
3117 *
3118 */
3119 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3120 u32 *sid)
3121 {
3122 int rc;
3123 struct context *ctx;
3124 struct context ctx_new;
3125
3126 if (!ss_initialized) {
3127 *sid = SECSID_NULL;
3128 return 0;
3129 }
3130
3131 read_lock(&policy_rwlock);
3132
3133 if (secattr->flags & NETLBL_SECATTR_CACHE)
3134 *sid = *(u32 *)secattr->cache->data;
3135 else if (secattr->flags & NETLBL_SECATTR_SECID)
3136 *sid = secattr->attr.secid;
3137 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3138 rc = -EIDRM;
3139 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3140 if (ctx == NULL)
3141 goto out;
3142
3143 context_init(&ctx_new);
3144 ctx_new.user = ctx->user;
3145 ctx_new.role = ctx->role;
3146 ctx_new.type = ctx->type;
3147 mls_import_netlbl_lvl(&ctx_new, secattr);
3148 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3149 rc = ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
3150 secattr->attr.mls.cat);
3151 if (rc)
3152 goto out;
3153 memcpy(&ctx_new.range.level[1].cat,
3154 &ctx_new.range.level[0].cat,
3155 sizeof(ctx_new.range.level[0].cat));
3156 }
3157 rc = -EIDRM;
3158 if (!mls_context_isvalid(&policydb, &ctx_new))
3159 goto out_free;
3160
3161 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3162 if (rc)
3163 goto out_free;
3164
3165 security_netlbl_cache_add(secattr, *sid);
3166
3167 ebitmap_destroy(&ctx_new.range.level[0].cat);
3168 } else
3169 *sid = SECSID_NULL;
3170
3171 read_unlock(&policy_rwlock);
3172 return 0;
3173 out_free:
3174 ebitmap_destroy(&ctx_new.range.level[0].cat);
3175 out:
3176 read_unlock(&policy_rwlock);
3177 return rc;
3178 }
3179
3180 /**
3181 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3182 * @sid: the SELinux SID
3183 * @secattr: the NetLabel packet security attributes
3184 *
3185 * Description:
3186 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3187 * Returns zero on success, negative values on failure.
3188 *
3189 */
3190 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3191 {
3192 int rc;
3193 struct context *ctx;
3194
3195 if (!ss_initialized)
3196 return 0;
3197
3198 read_lock(&policy_rwlock);
3199
3200 rc = -ENOENT;
3201 ctx = sidtab_search(&sidtab, sid);
3202 if (ctx == NULL)
3203 goto out;
3204
3205 rc = -ENOMEM;
3206 secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1),
3207 GFP_ATOMIC);
3208 if (secattr->domain == NULL)
3209 goto out;
3210
3211 secattr->attr.secid = sid;
3212 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3213 mls_export_netlbl_lvl(ctx, secattr);
3214 rc = mls_export_netlbl_cat(ctx, secattr);
3215 out:
3216 read_unlock(&policy_rwlock);
3217 return rc;
3218 }
3219 #endif /* CONFIG_NETLABEL */
3220
3221 /**
3222 * security_read_policy - read the policy.
3223 * @data: binary policy data
3224 * @len: length of data in bytes
3225 *
3226 */
3227 int security_read_policy(void **data, size_t *len)
3228 {
3229 int rc;
3230 struct policy_file fp;
3231
3232 if (!ss_initialized)
3233 return -EINVAL;
3234
3235 *len = security_policydb_len();
3236
3237 *data = vmalloc_user(*len);
3238 if (!*data)
3239 return -ENOMEM;
3240
3241 fp.data = *data;
3242 fp.len = *len;
3243
3244 read_lock(&policy_rwlock);
3245 rc = policydb_write(&policydb, &fp);
3246 read_unlock(&policy_rwlock);
3247
3248 if (rc)
3249 return rc;
3250
3251 *len = (unsigned long)fp.data - (unsigned long)*data;
3252 return 0;
3253
3254 }
kernel source for telekom puls (alcatel/mediatek)