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1ded0ec7e8c27a9b8b902a6d367d0db2d6d94f14
[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 *scontext = kstrdup(context->str, GFP_ATOMIC);
1022 if (!(*scontext))
1023 return -ENOMEM;
1024 return 0;
1025 }
1026
1027 /* Compute the size of the context. */
1028 *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1;
1029 *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1;
1030 *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1;
1031 *scontext_len += mls_compute_context_len(context);
1032
1033 if (!scontext)
1034 return 0;
1035
1036 /* Allocate space for the context; caller must free this space. */
1037 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1038 if (!scontextp)
1039 return -ENOMEM;
1040 *scontext = scontextp;
1041
1042 /*
1043 * Copy the user name, role name and type name into the context.
1044 */
1045 sprintf(scontextp, "%s:%s:%s",
1046 sym_name(&policydb, SYM_USERS, context->user - 1),
1047 sym_name(&policydb, SYM_ROLES, context->role - 1),
1048 sym_name(&policydb, SYM_TYPES, context->type - 1));
1049 scontextp += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) +
1050 1 + strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) +
1051 1 + strlen(sym_name(&policydb, SYM_TYPES, context->type - 1));
1052
1053 mls_sid_to_context(context, &scontextp);
1054
1055 *scontextp = 0;
1056
1057 return 0;
1058 }
1059
1060 #include "initial_sid_to_string.h"
1061
1062 const char *security_get_initial_sid_context(u32 sid)
1063 {
1064 if (unlikely(sid > SECINITSID_NUM))
1065 return NULL;
1066 return initial_sid_to_string[sid];
1067 }
1068
1069 static int security_sid_to_context_core(u32 sid, char **scontext,
1070 u32 *scontext_len, int force)
1071 {
1072 struct context *context;
1073 int rc = 0;
1074
1075 if (scontext)
1076 *scontext = NULL;
1077 *scontext_len = 0;
1078
1079 if (!ss_initialized) {
1080 if (sid <= SECINITSID_NUM) {
1081 char *scontextp;
1082
1083 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1084 if (!scontext)
1085 goto out;
1086 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1087 if (!scontextp) {
1088 rc = -ENOMEM;
1089 goto out;
1090 }
1091 strcpy(scontextp, initial_sid_to_string[sid]);
1092 *scontext = scontextp;
1093 goto out;
1094 }
1095 printk(KERN_ERR "SELinux: %s: called before initial "
1096 "load_policy on unknown SID %d\n", __func__, sid);
1097 rc = -EINVAL;
1098 goto out;
1099 }
1100 read_lock(&policy_rwlock);
1101 if (force)
1102 context = sidtab_search_force(&sidtab, sid);
1103 else
1104 context = sidtab_search(&sidtab, sid);
1105 if (!context) {
1106 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1107 __func__, sid);
1108 rc = -EINVAL;
1109 goto out_unlock;
1110 }
1111 rc = context_struct_to_string(context, scontext, scontext_len);
1112 out_unlock:
1113 read_unlock(&policy_rwlock);
1114 out:
1115 return rc;
1116
1117 }
1118
1119 /**
1120 * security_sid_to_context - Obtain a context for a given SID.
1121 * @sid: security identifier, SID
1122 * @scontext: security context
1123 * @scontext_len: length in bytes
1124 *
1125 * Write the string representation of the context associated with @sid
1126 * into a dynamically allocated string of the correct size. Set @scontext
1127 * to point to this string and set @scontext_len to the length of the string.
1128 */
1129 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1130 {
1131 return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1132 }
1133
1134 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1135 {
1136 return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1137 }
1138
1139 /*
1140 * Caveat: Mutates scontext.
1141 */
1142 static int string_to_context_struct(struct policydb *pol,
1143 struct sidtab *sidtabp,
1144 char *scontext,
1145 u32 scontext_len,
1146 struct context *ctx,
1147 u32 def_sid)
1148 {
1149 struct role_datum *role;
1150 struct type_datum *typdatum;
1151 struct user_datum *usrdatum;
1152 char *scontextp, *p, oldc;
1153 int rc = 0;
1154
1155 context_init(ctx);
1156
1157 /* Parse the security context. */
1158
1159 rc = -EINVAL;
1160 scontextp = (char *) scontext;
1161
1162 /* Extract the user. */
1163 p = scontextp;
1164 while (*p && *p != ':')
1165 p++;
1166
1167 if (*p == 0)
1168 goto out;
1169
1170 *p++ = 0;
1171
1172 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1173 if (!usrdatum)
1174 goto out;
1175
1176 ctx->user = usrdatum->value;
1177
1178 /* Extract role. */
1179 scontextp = p;
1180 while (*p && *p != ':')
1181 p++;
1182
1183 if (*p == 0)
1184 goto out;
1185
1186 *p++ = 0;
1187
1188 role = hashtab_search(pol->p_roles.table, scontextp);
1189 if (!role)
1190 goto out;
1191 ctx->role = role->value;
1192
1193 /* Extract type. */
1194 scontextp = p;
1195 while (*p && *p != ':')
1196 p++;
1197 oldc = *p;
1198 *p++ = 0;
1199
1200 typdatum = hashtab_search(pol->p_types.table, scontextp);
1201 if (!typdatum || typdatum->attribute)
1202 goto out;
1203
1204 ctx->type = typdatum->value;
1205
1206 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1207 if (rc)
1208 goto out;
1209
1210 rc = -EINVAL;
1211 if ((p - scontext) < scontext_len)
1212 goto out;
1213
1214 /* Check the validity of the new context. */
1215 if (!policydb_context_isvalid(pol, ctx))
1216 goto out;
1217 rc = 0;
1218 out:
1219 if (rc)
1220 context_destroy(ctx);
1221 return rc;
1222 }
1223
1224 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1225 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1226 int force)
1227 {
1228 char *scontext2, *str = NULL;
1229 struct context context;
1230 int rc = 0;
1231
1232 if (!ss_initialized) {
1233 int i;
1234
1235 for (i = 1; i < SECINITSID_NUM; i++) {
1236 if (!strcmp(initial_sid_to_string[i], scontext)) {
1237 *sid = i;
1238 return 0;
1239 }
1240 }
1241 *sid = SECINITSID_KERNEL;
1242 return 0;
1243 }
1244 *sid = SECSID_NULL;
1245
1246 /* Copy the string so that we can modify the copy as we parse it. */
1247 scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1248 if (!scontext2)
1249 return -ENOMEM;
1250 memcpy(scontext2, scontext, scontext_len);
1251 scontext2[scontext_len] = 0;
1252
1253 if (force) {
1254 /* Save another copy for storing in uninterpreted form */
1255 rc = -ENOMEM;
1256 str = kstrdup(scontext2, gfp_flags);
1257 if (!str)
1258 goto out;
1259 }
1260
1261 read_lock(&policy_rwlock);
1262 rc = string_to_context_struct(&policydb, &sidtab, scontext2,
1263 scontext_len, &context, def_sid);
1264 if (rc == -EINVAL && force) {
1265 context.str = str;
1266 context.len = scontext_len;
1267 str = NULL;
1268 } else if (rc)
1269 goto out_unlock;
1270 rc = sidtab_context_to_sid(&sidtab, &context, sid);
1271 context_destroy(&context);
1272 out_unlock:
1273 read_unlock(&policy_rwlock);
1274 out:
1275 kfree(scontext2);
1276 kfree(str);
1277 return rc;
1278 }
1279
1280 /**
1281 * security_context_to_sid - Obtain a SID for a given security context.
1282 * @scontext: security context
1283 * @scontext_len: length in bytes
1284 * @sid: security identifier, SID
1285 *
1286 * Obtains a SID associated with the security context that
1287 * has the string representation specified by @scontext.
1288 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1289 * memory is available, or 0 on success.
1290 */
1291 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
1292 {
1293 return security_context_to_sid_core(scontext, scontext_len,
1294 sid, SECSID_NULL, GFP_KERNEL, 0);
1295 }
1296
1297 /**
1298 * security_context_to_sid_default - Obtain a SID for a given security context,
1299 * falling back to specified default if needed.
1300 *
1301 * @scontext: security context
1302 * @scontext_len: length in bytes
1303 * @sid: security identifier, SID
1304 * @def_sid: default SID to assign on error
1305 *
1306 * Obtains a SID associated with the security context that
1307 * has the string representation specified by @scontext.
1308 * The default SID is passed to the MLS layer to be used to allow
1309 * kernel labeling of the MLS field if the MLS field is not present
1310 * (for upgrading to MLS without full relabel).
1311 * Implicitly forces adding of the context even if it cannot be mapped yet.
1312 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1313 * memory is available, or 0 on success.
1314 */
1315 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1316 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1317 {
1318 return security_context_to_sid_core(scontext, scontext_len,
1319 sid, def_sid, gfp_flags, 1);
1320 }
1321
1322 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1323 u32 *sid)
1324 {
1325 return security_context_to_sid_core(scontext, scontext_len,
1326 sid, SECSID_NULL, GFP_KERNEL, 1);
1327 }
1328
1329 static int compute_sid_handle_invalid_context(
1330 struct context *scontext,
1331 struct context *tcontext,
1332 u16 tclass,
1333 struct context *newcontext)
1334 {
1335 char *s = NULL, *t = NULL, *n = NULL;
1336 u32 slen, tlen, nlen;
1337
1338 if (context_struct_to_string(scontext, &s, &slen))
1339 goto out;
1340 if (context_struct_to_string(tcontext, &t, &tlen))
1341 goto out;
1342 if (context_struct_to_string(newcontext, &n, &nlen))
1343 goto out;
1344 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1345 "security_compute_sid: invalid context %s"
1346 " for scontext=%s"
1347 " tcontext=%s"
1348 " tclass=%s",
1349 n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
1350 out:
1351 kfree(s);
1352 kfree(t);
1353 kfree(n);
1354 if (!selinux_enforcing)
1355 return 0;
1356 return -EACCES;
1357 }
1358
1359 static void filename_compute_type(struct policydb *p, struct context *newcontext,
1360 u32 stype, u32 ttype, u16 tclass,
1361 const char *objname)
1362 {
1363 struct filename_trans ft;
1364 struct filename_trans_datum *otype;
1365
1366 /*
1367 * Most filename trans rules are going to live in specific directories
1368 * like /dev or /var/run. This bitmap will quickly skip rule searches
1369 * if the ttype does not contain any rules.
1370 */
1371 if (!ebitmap_get_bit(&p->filename_trans_ttypes, ttype))
1372 return;
1373
1374 ft.stype = stype;
1375 ft.ttype = ttype;
1376 ft.tclass = tclass;
1377 ft.name = objname;
1378
1379 otype = hashtab_search(p->filename_trans, &ft);
1380 if (otype)
1381 newcontext->type = otype->otype;
1382 }
1383
1384 static int security_compute_sid(u32 ssid,
1385 u32 tsid,
1386 u16 orig_tclass,
1387 u32 specified,
1388 const char *objname,
1389 u32 *out_sid,
1390 bool kern)
1391 {
1392 struct class_datum *cladatum = NULL;
1393 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1394 struct role_trans *roletr = NULL;
1395 struct avtab_key avkey;
1396 struct avtab_datum *avdatum;
1397 struct avtab_node *node;
1398 u16 tclass;
1399 int rc = 0;
1400 bool sock;
1401
1402 if (!ss_initialized) {
1403 switch (orig_tclass) {
1404 case SECCLASS_PROCESS: /* kernel value */
1405 *out_sid = ssid;
1406 break;
1407 default:
1408 *out_sid = tsid;
1409 break;
1410 }
1411 goto out;
1412 }
1413
1414 context_init(&newcontext);
1415
1416 read_lock(&policy_rwlock);
1417
1418 if (kern) {
1419 tclass = unmap_class(orig_tclass);
1420 sock = security_is_socket_class(orig_tclass);
1421 } else {
1422 tclass = orig_tclass;
1423 sock = security_is_socket_class(map_class(tclass));
1424 }
1425
1426 scontext = sidtab_search(&sidtab, ssid);
1427 if (!scontext) {
1428 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1429 __func__, ssid);
1430 rc = -EINVAL;
1431 goto out_unlock;
1432 }
1433 tcontext = sidtab_search(&sidtab, tsid);
1434 if (!tcontext) {
1435 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1436 __func__, tsid);
1437 rc = -EINVAL;
1438 goto out_unlock;
1439 }
1440
1441 if (tclass && tclass <= policydb.p_classes.nprim)
1442 cladatum = policydb.class_val_to_struct[tclass - 1];
1443
1444 /* Set the user identity. */
1445 switch (specified) {
1446 case AVTAB_TRANSITION:
1447 case AVTAB_CHANGE:
1448 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1449 newcontext.user = tcontext->user;
1450 } else {
1451 /* notice this gets both DEFAULT_SOURCE and unset */
1452 /* Use the process user identity. */
1453 newcontext.user = scontext->user;
1454 }
1455 break;
1456 case AVTAB_MEMBER:
1457 /* Use the related object owner. */
1458 newcontext.user = tcontext->user;
1459 break;
1460 }
1461
1462 /* Set the role to default values. */
1463 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1464 newcontext.role = scontext->role;
1465 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1466 newcontext.role = tcontext->role;
1467 } else {
1468 if ((tclass == policydb.process_class) || (sock == true))
1469 newcontext.role = scontext->role;
1470 else
1471 newcontext.role = OBJECT_R_VAL;
1472 }
1473
1474 /* Set the type to default values. */
1475 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1476 newcontext.type = scontext->type;
1477 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1478 newcontext.type = tcontext->type;
1479 } else {
1480 if ((tclass == policydb.process_class) || (sock == true)) {
1481 /* Use the type of process. */
1482 newcontext.type = scontext->type;
1483 } else {
1484 /* Use the type of the related object. */
1485 newcontext.type = tcontext->type;
1486 }
1487 }
1488
1489 /* Look for a type transition/member/change rule. */
1490 avkey.source_type = scontext->type;
1491 avkey.target_type = tcontext->type;
1492 avkey.target_class = tclass;
1493 avkey.specified = specified;
1494 avdatum = avtab_search(&policydb.te_avtab, &avkey);
1495
1496 /* If no permanent rule, also check for enabled conditional rules */
1497 if (!avdatum) {
1498 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1499 for (; node; node = avtab_search_node_next(node, specified)) {
1500 if (node->key.specified & AVTAB_ENABLED) {
1501 avdatum = &node->datum;
1502 break;
1503 }
1504 }
1505 }
1506
1507 if (avdatum) {
1508 /* Use the type from the type transition/member/change rule. */
1509 newcontext.type = avdatum->data;
1510 }
1511
1512 /* if we have a objname this is a file trans check so check those rules */
1513 if (objname)
1514 filename_compute_type(&policydb, &newcontext, scontext->type,
1515 tcontext->type, tclass, objname);
1516
1517 /* Check for class-specific changes. */
1518 if (specified & AVTAB_TRANSITION) {
1519 /* Look for a role transition rule. */
1520 for (roletr = policydb.role_tr; roletr; roletr = roletr->next) {
1521 if ((roletr->role == scontext->role) &&
1522 (roletr->type == tcontext->type) &&
1523 (roletr->tclass == tclass)) {
1524 /* Use the role transition rule. */
1525 newcontext.role = roletr->new_role;
1526 break;
1527 }
1528 }
1529 }
1530
1531 /* Set the MLS attributes.
1532 This is done last because it may allocate memory. */
1533 rc = mls_compute_sid(scontext, tcontext, tclass, specified,
1534 &newcontext, sock);
1535 if (rc)
1536 goto out_unlock;
1537
1538 /* Check the validity of the context. */
1539 if (!policydb_context_isvalid(&policydb, &newcontext)) {
1540 rc = compute_sid_handle_invalid_context(scontext,
1541 tcontext,
1542 tclass,
1543 &newcontext);
1544 if (rc)
1545 goto out_unlock;
1546 }
1547 /* Obtain the sid for the context. */
1548 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1549 out_unlock:
1550 read_unlock(&policy_rwlock);
1551 context_destroy(&newcontext);
1552 out:
1553 return rc;
1554 }
1555
1556 /**
1557 * security_transition_sid - Compute the SID for a new subject/object.
1558 * @ssid: source security identifier
1559 * @tsid: target security identifier
1560 * @tclass: target security class
1561 * @out_sid: security identifier for new subject/object
1562 *
1563 * Compute a SID to use for labeling a new subject or object in the
1564 * class @tclass based on a SID pair (@ssid, @tsid).
1565 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1566 * if insufficient memory is available, or %0 if the new SID was
1567 * computed successfully.
1568 */
1569 int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1570 const struct qstr *qstr, u32 *out_sid)
1571 {
1572 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1573 qstr ? qstr->name : NULL, out_sid, true);
1574 }
1575
1576 int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1577 const char *objname, u32 *out_sid)
1578 {
1579 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1580 objname, out_sid, false);
1581 }
1582
1583 /**
1584 * security_member_sid - Compute the SID for member selection.
1585 * @ssid: source security identifier
1586 * @tsid: target security identifier
1587 * @tclass: target security class
1588 * @out_sid: security identifier for selected member
1589 *
1590 * Compute a SID to use when selecting a member of a polyinstantiated
1591 * object of class @tclass based on a SID pair (@ssid, @tsid).
1592 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1593 * if insufficient memory is available, or %0 if the SID was
1594 * computed successfully.
1595 */
1596 int security_member_sid(u32 ssid,
1597 u32 tsid,
1598 u16 tclass,
1599 u32 *out_sid)
1600 {
1601 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL,
1602 out_sid, false);
1603 }
1604
1605 /**
1606 * security_change_sid - Compute the SID for object relabeling.
1607 * @ssid: source security identifier
1608 * @tsid: target security identifier
1609 * @tclass: target security class
1610 * @out_sid: security identifier for selected member
1611 *
1612 * Compute a SID to use for relabeling an object of class @tclass
1613 * based on a SID pair (@ssid, @tsid).
1614 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1615 * if insufficient memory is available, or %0 if the SID was
1616 * computed successfully.
1617 */
1618 int security_change_sid(u32 ssid,
1619 u32 tsid,
1620 u16 tclass,
1621 u32 *out_sid)
1622 {
1623 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1624 out_sid, false);
1625 }
1626
1627 /* Clone the SID into the new SID table. */
1628 static int clone_sid(u32 sid,
1629 struct context *context,
1630 void *arg)
1631 {
1632 struct sidtab *s = arg;
1633
1634 if (sid > SECINITSID_NUM)
1635 return sidtab_insert(s, sid, context);
1636 else
1637 return 0;
1638 }
1639
1640 static inline int convert_context_handle_invalid_context(struct context *context)
1641 {
1642 char *s;
1643 u32 len;
1644
1645 if (selinux_enforcing)
1646 return -EINVAL;
1647
1648 if (!context_struct_to_string(context, &s, &len)) {
1649 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s);
1650 kfree(s);
1651 }
1652 return 0;
1653 }
1654
1655 struct convert_context_args {
1656 struct policydb *oldp;
1657 struct policydb *newp;
1658 };
1659
1660 /*
1661 * Convert the values in the security context
1662 * structure `c' from the values specified
1663 * in the policy `p->oldp' to the values specified
1664 * in the policy `p->newp'. Verify that the
1665 * context is valid under the new policy.
1666 */
1667 static int convert_context(u32 key,
1668 struct context *c,
1669 void *p)
1670 {
1671 struct convert_context_args *args;
1672 struct context oldc;
1673 struct ocontext *oc;
1674 struct mls_range *range;
1675 struct role_datum *role;
1676 struct type_datum *typdatum;
1677 struct user_datum *usrdatum;
1678 char *s;
1679 u32 len;
1680 int rc = 0;
1681
1682 if (key <= SECINITSID_NUM)
1683 goto out;
1684
1685 args = p;
1686
1687 if (c->str) {
1688 struct context ctx;
1689
1690 rc = -ENOMEM;
1691 s = kstrdup(c->str, GFP_KERNEL);
1692 if (!s)
1693 goto out;
1694
1695 rc = string_to_context_struct(args->newp, NULL, s,
1696 c->len, &ctx, SECSID_NULL);
1697 kfree(s);
1698 if (!rc) {
1699 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n",
1700 c->str);
1701 /* Replace string with mapped representation. */
1702 kfree(c->str);
1703 memcpy(c, &ctx, sizeof(*c));
1704 goto out;
1705 } else if (rc == -EINVAL) {
1706 /* Retain string representation for later mapping. */
1707 rc = 0;
1708 goto out;
1709 } else {
1710 /* Other error condition, e.g. ENOMEM. */
1711 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n",
1712 c->str, -rc);
1713 goto out;
1714 }
1715 }
1716
1717 rc = context_cpy(&oldc, c);
1718 if (rc)
1719 goto out;
1720
1721 /* Convert the user. */
1722 rc = -EINVAL;
1723 usrdatum = hashtab_search(args->newp->p_users.table,
1724 sym_name(args->oldp, SYM_USERS, c->user - 1));
1725 if (!usrdatum)
1726 goto bad;
1727 c->user = usrdatum->value;
1728
1729 /* Convert the role. */
1730 rc = -EINVAL;
1731 role = hashtab_search(args->newp->p_roles.table,
1732 sym_name(args->oldp, SYM_ROLES, c->role - 1));
1733 if (!role)
1734 goto bad;
1735 c->role = role->value;
1736
1737 /* Convert the type. */
1738 rc = -EINVAL;
1739 typdatum = hashtab_search(args->newp->p_types.table,
1740 sym_name(args->oldp, SYM_TYPES, c->type - 1));
1741 if (!typdatum)
1742 goto bad;
1743 c->type = typdatum->value;
1744
1745 /* Convert the MLS fields if dealing with MLS policies */
1746 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1747 rc = mls_convert_context(args->oldp, args->newp, c);
1748 if (rc)
1749 goto bad;
1750 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1751 /*
1752 * Switching between MLS and non-MLS policy:
1753 * free any storage used by the MLS fields in the
1754 * context for all existing entries in the sidtab.
1755 */
1756 mls_context_destroy(c);
1757 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1758 /*
1759 * Switching between non-MLS and MLS policy:
1760 * ensure that the MLS fields of the context for all
1761 * existing entries in the sidtab are filled in with a
1762 * suitable default value, likely taken from one of the
1763 * initial SIDs.
1764 */
1765 oc = args->newp->ocontexts[OCON_ISID];
1766 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1767 oc = oc->next;
1768 rc = -EINVAL;
1769 if (!oc) {
1770 printk(KERN_ERR "SELinux: unable to look up"
1771 " the initial SIDs list\n");
1772 goto bad;
1773 }
1774 range = &oc->context[0].range;
1775 rc = mls_range_set(c, range);
1776 if (rc)
1777 goto bad;
1778 }
1779
1780 /* Check the validity of the new context. */
1781 if (!policydb_context_isvalid(args->newp, c)) {
1782 rc = convert_context_handle_invalid_context(&oldc);
1783 if (rc)
1784 goto bad;
1785 }
1786
1787 context_destroy(&oldc);
1788
1789 rc = 0;
1790 out:
1791 return rc;
1792 bad:
1793 /* Map old representation to string and save it. */
1794 rc = context_struct_to_string(&oldc, &s, &len);
1795 if (rc)
1796 return rc;
1797 context_destroy(&oldc);
1798 context_destroy(c);
1799 c->str = s;
1800 c->len = len;
1801 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n",
1802 c->str);
1803 rc = 0;
1804 goto out;
1805 }
1806
1807 static void security_load_policycaps(void)
1808 {
1809 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1810 POLICYDB_CAPABILITY_NETPEER);
1811 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1812 POLICYDB_CAPABILITY_OPENPERM);
1813 }
1814
1815 static int security_preserve_bools(struct policydb *p);
1816
1817 /**
1818 * security_load_policy - Load a security policy configuration.
1819 * @data: binary policy data
1820 * @len: length of data in bytes
1821 *
1822 * Load a new set of security policy configuration data,
1823 * validate it and convert the SID table as necessary.
1824 * This function will flush the access vector cache after
1825 * loading the new policy.
1826 */
1827 int security_load_policy(void *data, size_t len)
1828 {
1829 struct policydb oldpolicydb, newpolicydb;
1830 struct sidtab oldsidtab, newsidtab;
1831 struct selinux_mapping *oldmap, *map = NULL;
1832 struct convert_context_args args;
1833 u32 seqno;
1834 u16 map_size;
1835 int rc = 0;
1836 struct policy_file file = { data, len }, *fp = &file;
1837
1838 if (!ss_initialized) {
1839 avtab_cache_init();
1840 rc = policydb_read(&policydb, fp);
1841 if (rc) {
1842 avtab_cache_destroy();
1843 return rc;
1844 }
1845
1846 policydb.len = len;
1847 rc = selinux_set_mapping(&policydb, secclass_map,
1848 &current_mapping,
1849 &current_mapping_size);
1850 if (rc) {
1851 policydb_destroy(&policydb);
1852 avtab_cache_destroy();
1853 return rc;
1854 }
1855
1856 rc = policydb_load_isids(&policydb, &sidtab);
1857 if (rc) {
1858 policydb_destroy(&policydb);
1859 avtab_cache_destroy();
1860 return rc;
1861 }
1862
1863 security_load_policycaps();
1864 ss_initialized = 1;
1865 seqno = ++latest_granting;
1866 selinux_complete_init();
1867 avc_ss_reset(seqno);
1868 selnl_notify_policyload(seqno);
1869 selinux_status_update_policyload(seqno);
1870 selinux_netlbl_cache_invalidate();
1871 selinux_xfrm_notify_policyload();
1872 return 0;
1873 }
1874
1875 #if 0
1876 sidtab_hash_eval(&sidtab, "sids");
1877 #endif
1878
1879 rc = policydb_read(&newpolicydb, fp);
1880 if (rc)
1881 return rc;
1882
1883 newpolicydb.len = len;
1884 /* If switching between different policy types, log MLS status */
1885 if (policydb.mls_enabled && !newpolicydb.mls_enabled)
1886 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
1887 else if (!policydb.mls_enabled && newpolicydb.mls_enabled)
1888 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
1889
1890 rc = policydb_load_isids(&newpolicydb, &newsidtab);
1891 if (rc) {
1892 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
1893 policydb_destroy(&newpolicydb);
1894 return rc;
1895 }
1896
1897 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size);
1898 if (rc)
1899 goto err;
1900
1901 rc = security_preserve_bools(&newpolicydb);
1902 if (rc) {
1903 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
1904 goto err;
1905 }
1906
1907 /* Clone the SID table. */
1908 sidtab_shutdown(&sidtab);
1909
1910 rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
1911 if (rc)
1912 goto err;
1913
1914 /*
1915 * Convert the internal representations of contexts
1916 * in the new SID table.
1917 */
1918 args.oldp = &policydb;
1919 args.newp = &newpolicydb;
1920 rc = sidtab_map(&newsidtab, convert_context, &args);
1921 if (rc) {
1922 printk(KERN_ERR "SELinux: unable to convert the internal"
1923 " representation of contexts in the new SID"
1924 " table\n");
1925 goto err;
1926 }
1927
1928 /* Save the old policydb and SID table to free later. */
1929 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1930 sidtab_set(&oldsidtab, &sidtab);
1931
1932 /* Install the new policydb and SID table. */
1933 write_lock_irq(&policy_rwlock);
1934 memcpy(&policydb, &newpolicydb, sizeof policydb);
1935 sidtab_set(&sidtab, &newsidtab);
1936 security_load_policycaps();
1937 oldmap = current_mapping;
1938 current_mapping = map;
1939 current_mapping_size = map_size;
1940 seqno = ++latest_granting;
1941 write_unlock_irq(&policy_rwlock);
1942
1943 /* Free the old policydb and SID table. */
1944 policydb_destroy(&oldpolicydb);
1945 sidtab_destroy(&oldsidtab);
1946 kfree(oldmap);
1947
1948 avc_ss_reset(seqno);
1949 selnl_notify_policyload(seqno);
1950 selinux_status_update_policyload(seqno);
1951 selinux_netlbl_cache_invalidate();
1952 selinux_xfrm_notify_policyload();
1953
1954 return 0;
1955
1956 err:
1957 kfree(map);
1958 sidtab_destroy(&newsidtab);
1959 policydb_destroy(&newpolicydb);
1960 return rc;
1961
1962 }
1963
1964 size_t security_policydb_len(void)
1965 {
1966 size_t len;
1967
1968 read_lock(&policy_rwlock);
1969 len = policydb.len;
1970 read_unlock(&policy_rwlock);
1971
1972 return len;
1973 }
1974
1975 /**
1976 * security_port_sid - Obtain the SID for a port.
1977 * @protocol: protocol number
1978 * @port: port number
1979 * @out_sid: security identifier
1980 */
1981 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1982 {
1983 struct ocontext *c;
1984 int rc = 0;
1985
1986 read_lock(&policy_rwlock);
1987
1988 c = policydb.ocontexts[OCON_PORT];
1989 while (c) {
1990 if (c->u.port.protocol == protocol &&
1991 c->u.port.low_port <= port &&
1992 c->u.port.high_port >= port)
1993 break;
1994 c = c->next;
1995 }
1996
1997 if (c) {
1998 if (!c->sid[0]) {
1999 rc = sidtab_context_to_sid(&sidtab,
2000 &c->context[0],
2001 &c->sid[0]);
2002 if (rc)
2003 goto out;
2004 }
2005 *out_sid = c->sid[0];
2006 } else {
2007 *out_sid = SECINITSID_PORT;
2008 }
2009
2010 out:
2011 read_unlock(&policy_rwlock);
2012 return rc;
2013 }
2014
2015 /**
2016 * security_netif_sid - Obtain the SID for a network interface.
2017 * @name: interface name
2018 * @if_sid: interface SID
2019 */
2020 int security_netif_sid(char *name, u32 *if_sid)
2021 {
2022 int rc = 0;
2023 struct ocontext *c;
2024
2025 read_lock(&policy_rwlock);
2026
2027 c = policydb.ocontexts[OCON_NETIF];
2028 while (c) {
2029 if (strcmp(name, c->u.name) == 0)
2030 break;
2031 c = c->next;
2032 }
2033
2034 if (c) {
2035 if (!c->sid[0] || !c->sid[1]) {
2036 rc = sidtab_context_to_sid(&sidtab,
2037 &c->context[0],
2038 &c->sid[0]);
2039 if (rc)
2040 goto out;
2041 rc = sidtab_context_to_sid(&sidtab,
2042 &c->context[1],
2043 &c->sid[1]);
2044 if (rc)
2045 goto out;
2046 }
2047 *if_sid = c->sid[0];
2048 } else
2049 *if_sid = SECINITSID_NETIF;
2050
2051 out:
2052 read_unlock(&policy_rwlock);
2053 return rc;
2054 }
2055
2056 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2057 {
2058 int i, fail = 0;
2059
2060 for (i = 0; i < 4; i++)
2061 if (addr[i] != (input[i] & mask[i])) {
2062 fail = 1;
2063 break;
2064 }
2065
2066 return !fail;
2067 }
2068
2069 /**
2070 * security_node_sid - Obtain the SID for a node (host).
2071 * @domain: communication domain aka address family
2072 * @addrp: address
2073 * @addrlen: address length in bytes
2074 * @out_sid: security identifier
2075 */
2076 int security_node_sid(u16 domain,
2077 void *addrp,
2078 u32 addrlen,
2079 u32 *out_sid)
2080 {
2081 int rc;
2082 struct ocontext *c;
2083
2084 read_lock(&policy_rwlock);
2085
2086 switch (domain) {
2087 case AF_INET: {
2088 u32 addr;
2089
2090 rc = -EINVAL;
2091 if (addrlen != sizeof(u32))
2092 goto out;
2093
2094 addr = *((u32 *)addrp);
2095
2096 c = policydb.ocontexts[OCON_NODE];
2097 while (c) {
2098 if (c->u.node.addr == (addr & c->u.node.mask))
2099 break;
2100 c = c->next;
2101 }
2102 break;
2103 }
2104
2105 case AF_INET6:
2106 rc = -EINVAL;
2107 if (addrlen != sizeof(u64) * 2)
2108 goto out;
2109 c = policydb.ocontexts[OCON_NODE6];
2110 while (c) {
2111 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2112 c->u.node6.mask))
2113 break;
2114 c = c->next;
2115 }
2116 break;
2117
2118 default:
2119 rc = 0;
2120 *out_sid = SECINITSID_NODE;
2121 goto out;
2122 }
2123
2124 if (c) {
2125 if (!c->sid[0]) {
2126 rc = sidtab_context_to_sid(&sidtab,
2127 &c->context[0],
2128 &c->sid[0]);
2129 if (rc)
2130 goto out;
2131 }
2132 *out_sid = c->sid[0];
2133 } else {
2134 *out_sid = SECINITSID_NODE;
2135 }
2136
2137 rc = 0;
2138 out:
2139 read_unlock(&policy_rwlock);
2140 return rc;
2141 }
2142
2143 #define SIDS_NEL 25
2144
2145 /**
2146 * security_get_user_sids - Obtain reachable SIDs for a user.
2147 * @fromsid: starting SID
2148 * @username: username
2149 * @sids: array of reachable SIDs for user
2150 * @nel: number of elements in @sids
2151 *
2152 * Generate the set of SIDs for legal security contexts
2153 * for a given user that can be reached by @fromsid.
2154 * Set *@sids to point to a dynamically allocated
2155 * array containing the set of SIDs. Set *@nel to the
2156 * number of elements in the array.
2157 */
2158
2159 int security_get_user_sids(u32 fromsid,
2160 char *username,
2161 u32 **sids,
2162 u32 *nel)
2163 {
2164 struct context *fromcon, usercon;
2165 u32 *mysids = NULL, *mysids2, sid;
2166 u32 mynel = 0, maxnel = SIDS_NEL;
2167 struct user_datum *user;
2168 struct role_datum *role;
2169 struct ebitmap_node *rnode, *tnode;
2170 int rc = 0, i, j;
2171
2172 *sids = NULL;
2173 *nel = 0;
2174
2175 if (!ss_initialized)
2176 goto out;
2177
2178 read_lock(&policy_rwlock);
2179
2180 context_init(&usercon);
2181
2182 rc = -EINVAL;
2183 fromcon = sidtab_search(&sidtab, fromsid);
2184 if (!fromcon)
2185 goto out_unlock;
2186
2187 rc = -EINVAL;
2188 user = hashtab_search(policydb.p_users.table, username);
2189 if (!user)
2190 goto out_unlock;
2191
2192 usercon.user = user->value;
2193
2194 rc = -ENOMEM;
2195 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2196 if (!mysids)
2197 goto out_unlock;
2198
2199 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2200 role = policydb.role_val_to_struct[i];
2201 usercon.role = i + 1;
2202 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2203 usercon.type = j + 1;
2204
2205 if (mls_setup_user_range(fromcon, user, &usercon))
2206 continue;
2207
2208 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2209 if (rc)
2210 goto out_unlock;
2211 if (mynel < maxnel) {
2212 mysids[mynel++] = sid;
2213 } else {
2214 rc = -ENOMEM;
2215 maxnel += SIDS_NEL;
2216 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2217 if (!mysids2)
2218 goto out_unlock;
2219 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2220 kfree(mysids);
2221 mysids = mysids2;
2222 mysids[mynel++] = sid;
2223 }
2224 }
2225 }
2226 rc = 0;
2227 out_unlock:
2228 read_unlock(&policy_rwlock);
2229 if (rc || !mynel) {
2230 kfree(mysids);
2231 goto out;
2232 }
2233
2234 rc = -ENOMEM;
2235 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2236 if (!mysids2) {
2237 kfree(mysids);
2238 goto out;
2239 }
2240 for (i = 0, j = 0; i < mynel; i++) {
2241 struct av_decision dummy_avd;
2242 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2243 SECCLASS_PROCESS, /* kernel value */
2244 PROCESS__TRANSITION, AVC_STRICT,
2245 &dummy_avd);
2246 if (!rc)
2247 mysids2[j++] = mysids[i];
2248 cond_resched();
2249 }
2250 rc = 0;
2251 kfree(mysids);
2252 *sids = mysids2;
2253 *nel = j;
2254 out:
2255 return rc;
2256 }
2257
2258 /**
2259 * security_genfs_sid - Obtain a SID for a file in a filesystem
2260 * @fstype: filesystem type
2261 * @path: path from root of mount
2262 * @sclass: file security class
2263 * @sid: SID for path
2264 *
2265 * Obtain a SID to use for a file in a filesystem that
2266 * cannot support xattr or use a fixed labeling behavior like
2267 * transition SIDs or task SIDs.
2268 */
2269 int security_genfs_sid(const char *fstype,
2270 char *path,
2271 u16 orig_sclass,
2272 u32 *sid)
2273 {
2274 int len;
2275 u16 sclass;
2276 struct genfs *genfs;
2277 struct ocontext *c;
2278 int rc, cmp = 0;
2279
2280 while (path[0] == '/' && path[1] == '/')
2281 path++;
2282
2283 read_lock(&policy_rwlock);
2284
2285 sclass = unmap_class(orig_sclass);
2286 *sid = SECINITSID_UNLABELED;
2287
2288 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2289 cmp = strcmp(fstype, genfs->fstype);
2290 if (cmp <= 0)
2291 break;
2292 }
2293
2294 rc = -ENOENT;
2295 if (!genfs || cmp)
2296 goto out;
2297
2298 for (c = genfs->head; c; c = c->next) {
2299 len = strlen(c->u.name);
2300 if ((!c->v.sclass || sclass == c->v.sclass) &&
2301 (strncmp(c->u.name, path, len) == 0))
2302 break;
2303 }
2304
2305 rc = -ENOENT;
2306 if (!c)
2307 goto out;
2308
2309 if (!c->sid[0]) {
2310 rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]);
2311 if (rc)
2312 goto out;
2313 }
2314
2315 *sid = c->sid[0];
2316 rc = 0;
2317 out:
2318 read_unlock(&policy_rwlock);
2319 return rc;
2320 }
2321
2322 /**
2323 * security_fs_use - Determine how to handle labeling for a filesystem.
2324 * @fstype: filesystem type
2325 * @behavior: labeling behavior
2326 * @sid: SID for filesystem (superblock)
2327 */
2328 int security_fs_use(
2329 const char *fstype,
2330 unsigned int *behavior,
2331 u32 *sid)
2332 {
2333 int rc = 0;
2334 struct ocontext *c;
2335
2336 read_lock(&policy_rwlock);
2337
2338 c = policydb.ocontexts[OCON_FSUSE];
2339 while (c) {
2340 if (strcmp(fstype, c->u.name) == 0)
2341 break;
2342 c = c->next;
2343 }
2344
2345 if (c) {
2346 *behavior = c->v.behavior;
2347 if (!c->sid[0]) {
2348 rc = sidtab_context_to_sid(&sidtab, &c->context[0],
2349 &c->sid[0]);
2350 if (rc)
2351 goto out;
2352 }
2353 *sid = c->sid[0];
2354 } else {
2355 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
2356 if (rc) {
2357 *behavior = SECURITY_FS_USE_NONE;
2358 rc = 0;
2359 } else {
2360 *behavior = SECURITY_FS_USE_GENFS;
2361 }
2362 }
2363
2364 out:
2365 read_unlock(&policy_rwlock);
2366 return rc;
2367 }
2368
2369 int security_get_bools(int *len, char ***names, int **values)
2370 {
2371 int i, rc;
2372
2373 read_lock(&policy_rwlock);
2374 *names = NULL;
2375 *values = NULL;
2376
2377 rc = 0;
2378 *len = policydb.p_bools.nprim;
2379 if (!*len)
2380 goto out;
2381
2382 rc = -ENOMEM;
2383 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2384 if (!*names)
2385 goto err;
2386
2387 rc = -ENOMEM;
2388 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2389 if (!*values)
2390 goto err;
2391
2392 for (i = 0; i < *len; i++) {
2393 size_t name_len;
2394
2395 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2396 name_len = strlen(sym_name(&policydb, SYM_BOOLS, i)) + 1;
2397
2398 rc = -ENOMEM;
2399 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
2400 if (!(*names)[i])
2401 goto err;
2402
2403 strncpy((*names)[i], sym_name(&policydb, SYM_BOOLS, i), name_len);
2404 (*names)[i][name_len - 1] = 0;
2405 }
2406 rc = 0;
2407 out:
2408 read_unlock(&policy_rwlock);
2409 return rc;
2410 err:
2411 if (*names) {
2412 for (i = 0; i < *len; i++)
2413 kfree((*names)[i]);
2414 }
2415 kfree(*values);
2416 goto out;
2417 }
2418
2419
2420 int security_set_bools(int len, int *values)
2421 {
2422 int i, rc;
2423 int lenp, seqno = 0;
2424 struct cond_node *cur;
2425
2426 write_lock_irq(&policy_rwlock);
2427
2428 rc = -EFAULT;
2429 lenp = policydb.p_bools.nprim;
2430 if (len != lenp)
2431 goto out;
2432
2433 for (i = 0; i < len; i++) {
2434 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2435 audit_log(current->audit_context, GFP_ATOMIC,
2436 AUDIT_MAC_CONFIG_CHANGE,
2437 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2438 sym_name(&policydb, SYM_BOOLS, i),
2439 !!values[i],
2440 policydb.bool_val_to_struct[i]->state,
2441 audit_get_loginuid(current),
2442 audit_get_sessionid(current));
2443 }
2444 if (values[i])
2445 policydb.bool_val_to_struct[i]->state = 1;
2446 else
2447 policydb.bool_val_to_struct[i]->state = 0;
2448 }
2449
2450 for (cur = policydb.cond_list; cur; cur = cur->next) {
2451 rc = evaluate_cond_node(&policydb, cur);
2452 if (rc)
2453 goto out;
2454 }
2455
2456 seqno = ++latest_granting;
2457 rc = 0;
2458 out:
2459 write_unlock_irq(&policy_rwlock);
2460 if (!rc) {
2461 avc_ss_reset(seqno);
2462 selnl_notify_policyload(seqno);
2463 selinux_status_update_policyload(seqno);
2464 selinux_xfrm_notify_policyload();
2465 }
2466 return rc;
2467 }
2468
2469 int security_get_bool_value(int bool)
2470 {
2471 int rc;
2472 int len;
2473
2474 read_lock(&policy_rwlock);
2475
2476 rc = -EFAULT;
2477 len = policydb.p_bools.nprim;
2478 if (bool >= len)
2479 goto out;
2480
2481 rc = policydb.bool_val_to_struct[bool]->state;
2482 out:
2483 read_unlock(&policy_rwlock);
2484 return rc;
2485 }
2486
2487 static int security_preserve_bools(struct policydb *p)
2488 {
2489 int rc, nbools = 0, *bvalues = NULL, i;
2490 char **bnames = NULL;
2491 struct cond_bool_datum *booldatum;
2492 struct cond_node *cur;
2493
2494 rc = security_get_bools(&nbools, &bnames, &bvalues);
2495 if (rc)
2496 goto out;
2497 for (i = 0; i < nbools; i++) {
2498 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2499 if (booldatum)
2500 booldatum->state = bvalues[i];
2501 }
2502 for (cur = p->cond_list; cur; cur = cur->next) {
2503 rc = evaluate_cond_node(p, cur);
2504 if (rc)
2505 goto out;
2506 }
2507
2508 out:
2509 if (bnames) {
2510 for (i = 0; i < nbools; i++)
2511 kfree(bnames[i]);
2512 }
2513 kfree(bnames);
2514 kfree(bvalues);
2515 return rc;
2516 }
2517
2518 /*
2519 * security_sid_mls_copy() - computes a new sid based on the given
2520 * sid and the mls portion of mls_sid.
2521 */
2522 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2523 {
2524 struct context *context1;
2525 struct context *context2;
2526 struct context newcon;
2527 char *s;
2528 u32 len;
2529 int rc;
2530
2531 rc = 0;
2532 if (!ss_initialized || !policydb.mls_enabled) {
2533 *new_sid = sid;
2534 goto out;
2535 }
2536
2537 context_init(&newcon);
2538
2539 read_lock(&policy_rwlock);
2540
2541 rc = -EINVAL;
2542 context1 = sidtab_search(&sidtab, sid);
2543 if (!context1) {
2544 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2545 __func__, sid);
2546 goto out_unlock;
2547 }
2548
2549 rc = -EINVAL;
2550 context2 = sidtab_search(&sidtab, mls_sid);
2551 if (!context2) {
2552 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2553 __func__, mls_sid);
2554 goto out_unlock;
2555 }
2556
2557 newcon.user = context1->user;
2558 newcon.role = context1->role;
2559 newcon.type = context1->type;
2560 rc = mls_context_cpy(&newcon, context2);
2561 if (rc)
2562 goto out_unlock;
2563
2564 /* Check the validity of the new context. */
2565 if (!policydb_context_isvalid(&policydb, &newcon)) {
2566 rc = convert_context_handle_invalid_context(&newcon);
2567 if (rc) {
2568 if (!context_struct_to_string(&newcon, &s, &len)) {
2569 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2570 "security_sid_mls_copy: invalid context %s", s);
2571 kfree(s);
2572 }
2573 goto out_unlock;
2574 }
2575 }
2576
2577 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2578 out_unlock:
2579 read_unlock(&policy_rwlock);
2580 context_destroy(&newcon);
2581 out:
2582 return rc;
2583 }
2584
2585 /**
2586 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2587 * @nlbl_sid: NetLabel SID
2588 * @nlbl_type: NetLabel labeling protocol type
2589 * @xfrm_sid: XFRM SID
2590 *
2591 * Description:
2592 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2593 * resolved into a single SID it is returned via @peer_sid and the function
2594 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
2595 * returns a negative value. A table summarizing the behavior is below:
2596 *
2597 * | function return | @sid
2598 * ------------------------------+-----------------+-----------------
2599 * no peer labels | 0 | SECSID_NULL
2600 * single peer label | 0 | <peer_label>
2601 * multiple, consistent labels | 0 | <peer_label>
2602 * multiple, inconsistent labels | -<errno> | SECSID_NULL
2603 *
2604 */
2605 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2606 u32 xfrm_sid,
2607 u32 *peer_sid)
2608 {
2609 int rc;
2610 struct context *nlbl_ctx;
2611 struct context *xfrm_ctx;
2612
2613 *peer_sid = SECSID_NULL;
2614
2615 /* handle the common (which also happens to be the set of easy) cases
2616 * right away, these two if statements catch everything involving a
2617 * single or absent peer SID/label */
2618 if (xfrm_sid == SECSID_NULL) {
2619 *peer_sid = nlbl_sid;
2620 return 0;
2621 }
2622 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2623 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2624 * is present */
2625 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2626 *peer_sid = xfrm_sid;
2627 return 0;
2628 }
2629
2630 /* we don't need to check ss_initialized here since the only way both
2631 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2632 * security server was initialized and ss_initialized was true */
2633 if (!policydb.mls_enabled)
2634 return 0;
2635
2636 read_lock(&policy_rwlock);
2637
2638 rc = -EINVAL;
2639 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2640 if (!nlbl_ctx) {
2641 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2642 __func__, nlbl_sid);
2643 goto out;
2644 }
2645 rc = -EINVAL;
2646 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2647 if (!xfrm_ctx) {
2648 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2649 __func__, xfrm_sid);
2650 goto out;
2651 }
2652 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2653 if (rc)
2654 goto out;
2655
2656 /* at present NetLabel SIDs/labels really only carry MLS
2657 * information so if the MLS portion of the NetLabel SID
2658 * matches the MLS portion of the labeled XFRM SID/label
2659 * then pass along the XFRM SID as it is the most
2660 * expressive */
2661 *peer_sid = xfrm_sid;
2662 out:
2663 read_unlock(&policy_rwlock);
2664 return rc;
2665 }
2666
2667 static int get_classes_callback(void *k, void *d, void *args)
2668 {
2669 struct class_datum *datum = d;
2670 char *name = k, **classes = args;
2671 int value = datum->value - 1;
2672
2673 classes[value] = kstrdup(name, GFP_ATOMIC);
2674 if (!classes[value])
2675 return -ENOMEM;
2676
2677 return 0;
2678 }
2679
2680 int security_get_classes(char ***classes, int *nclasses)
2681 {
2682 int rc;
2683
2684 read_lock(&policy_rwlock);
2685
2686 rc = -ENOMEM;
2687 *nclasses = policydb.p_classes.nprim;
2688 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
2689 if (!*classes)
2690 goto out;
2691
2692 rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2693 *classes);
2694 if (rc) {
2695 int i;
2696 for (i = 0; i < *nclasses; i++)
2697 kfree((*classes)[i]);
2698 kfree(*classes);
2699 }
2700
2701 out:
2702 read_unlock(&policy_rwlock);
2703 return rc;
2704 }
2705
2706 static int get_permissions_callback(void *k, void *d, void *args)
2707 {
2708 struct perm_datum *datum = d;
2709 char *name = k, **perms = args;
2710 int value = datum->value - 1;
2711
2712 perms[value] = kstrdup(name, GFP_ATOMIC);
2713 if (!perms[value])
2714 return -ENOMEM;
2715
2716 return 0;
2717 }
2718
2719 int security_get_permissions(char *class, char ***perms, int *nperms)
2720 {
2721 int rc, i;
2722 struct class_datum *match;
2723
2724 read_lock(&policy_rwlock);
2725
2726 rc = -EINVAL;
2727 match = hashtab_search(policydb.p_classes.table, class);
2728 if (!match) {
2729 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
2730 __func__, class);
2731 goto out;
2732 }
2733
2734 rc = -ENOMEM;
2735 *nperms = match->permissions.nprim;
2736 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
2737 if (!*perms)
2738 goto out;
2739
2740 if (match->comdatum) {
2741 rc = hashtab_map(match->comdatum->permissions.table,
2742 get_permissions_callback, *perms);
2743 if (rc)
2744 goto err;
2745 }
2746
2747 rc = hashtab_map(match->permissions.table, get_permissions_callback,
2748 *perms);
2749 if (rc)
2750 goto err;
2751
2752 out:
2753 read_unlock(&policy_rwlock);
2754 return rc;
2755
2756 err:
2757 read_unlock(&policy_rwlock);
2758 for (i = 0; i < *nperms; i++)
2759 kfree((*perms)[i]);
2760 kfree(*perms);
2761 return rc;
2762 }
2763
2764 int security_get_reject_unknown(void)
2765 {
2766 return policydb.reject_unknown;
2767 }
2768
2769 int security_get_allow_unknown(void)
2770 {
2771 return policydb.allow_unknown;
2772 }
2773
2774 /**
2775 * security_policycap_supported - Check for a specific policy capability
2776 * @req_cap: capability
2777 *
2778 * Description:
2779 * This function queries the currently loaded policy to see if it supports the
2780 * capability specified by @req_cap. Returns true (1) if the capability is
2781 * supported, false (0) if it isn't supported.
2782 *
2783 */
2784 int security_policycap_supported(unsigned int req_cap)
2785 {
2786 int rc;
2787
2788 read_lock(&policy_rwlock);
2789 rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2790 read_unlock(&policy_rwlock);
2791
2792 return rc;
2793 }
2794
2795 struct selinux_audit_rule {
2796 u32 au_seqno;
2797 struct context au_ctxt;
2798 };
2799
2800 void selinux_audit_rule_free(void *vrule)
2801 {
2802 struct selinux_audit_rule *rule = vrule;
2803
2804 if (rule) {
2805 context_destroy(&rule->au_ctxt);
2806 kfree(rule);
2807 }
2808 }
2809
2810 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2811 {
2812 struct selinux_audit_rule *tmprule;
2813 struct role_datum *roledatum;
2814 struct type_datum *typedatum;
2815 struct user_datum *userdatum;
2816 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2817 int rc = 0;
2818
2819 *rule = NULL;
2820
2821 if (!ss_initialized)
2822 return -EOPNOTSUPP;
2823
2824 switch (field) {
2825 case AUDIT_SUBJ_USER:
2826 case AUDIT_SUBJ_ROLE:
2827 case AUDIT_SUBJ_TYPE:
2828 case AUDIT_OBJ_USER:
2829 case AUDIT_OBJ_ROLE:
2830 case AUDIT_OBJ_TYPE:
2831 /* only 'equals' and 'not equals' fit user, role, and type */
2832 if (op != Audit_equal && op != Audit_not_equal)
2833 return -EINVAL;
2834 break;
2835 case AUDIT_SUBJ_SEN:
2836 case AUDIT_SUBJ_CLR:
2837 case AUDIT_OBJ_LEV_LOW:
2838 case AUDIT_OBJ_LEV_HIGH:
2839 /* we do not allow a range, indicated by the presence of '-' */
2840 if (strchr(rulestr, '-'))
2841 return -EINVAL;
2842 break;
2843 default:
2844 /* only the above fields are valid */
2845 return -EINVAL;
2846 }
2847
2848 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2849 if (!tmprule)
2850 return -ENOMEM;
2851
2852 context_init(&tmprule->au_ctxt);
2853
2854 read_lock(&policy_rwlock);
2855
2856 tmprule->au_seqno = latest_granting;
2857
2858 switch (field) {
2859 case AUDIT_SUBJ_USER:
2860 case AUDIT_OBJ_USER:
2861 rc = -EINVAL;
2862 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2863 if (!userdatum)
2864 goto out;
2865 tmprule->au_ctxt.user = userdatum->value;
2866 break;
2867 case AUDIT_SUBJ_ROLE:
2868 case AUDIT_OBJ_ROLE:
2869 rc = -EINVAL;
2870 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2871 if (!roledatum)
2872 goto out;
2873 tmprule->au_ctxt.role = roledatum->value;
2874 break;
2875 case AUDIT_SUBJ_TYPE:
2876 case AUDIT_OBJ_TYPE:
2877 rc = -EINVAL;
2878 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2879 if (!typedatum)
2880 goto out;
2881 tmprule->au_ctxt.type = typedatum->value;
2882 break;
2883 case AUDIT_SUBJ_SEN:
2884 case AUDIT_SUBJ_CLR:
2885 case AUDIT_OBJ_LEV_LOW:
2886 case AUDIT_OBJ_LEV_HIGH:
2887 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2888 if (rc)
2889 goto out;
2890 break;
2891 }
2892 rc = 0;
2893 out:
2894 read_unlock(&policy_rwlock);
2895
2896 if (rc) {
2897 selinux_audit_rule_free(tmprule);
2898 tmprule = NULL;
2899 }
2900
2901 *rule = tmprule;
2902
2903 return rc;
2904 }
2905
2906 /* Check to see if the rule contains any selinux fields */
2907 int selinux_audit_rule_known(struct audit_krule *rule)
2908 {
2909 int i;
2910
2911 for (i = 0; i < rule->field_count; i++) {
2912 struct audit_field *f = &rule->fields[i];
2913 switch (f->type) {
2914 case AUDIT_SUBJ_USER:
2915 case AUDIT_SUBJ_ROLE:
2916 case AUDIT_SUBJ_TYPE:
2917 case AUDIT_SUBJ_SEN:
2918 case AUDIT_SUBJ_CLR:
2919 case AUDIT_OBJ_USER:
2920 case AUDIT_OBJ_ROLE:
2921 case AUDIT_OBJ_TYPE:
2922 case AUDIT_OBJ_LEV_LOW:
2923 case AUDIT_OBJ_LEV_HIGH:
2924 return 1;
2925 }
2926 }
2927
2928 return 0;
2929 }
2930
2931 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2932 struct audit_context *actx)
2933 {
2934 struct context *ctxt;
2935 struct mls_level *level;
2936 struct selinux_audit_rule *rule = vrule;
2937 int match = 0;
2938
2939 if (!rule) {
2940 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2941 "selinux_audit_rule_match: missing rule\n");
2942 return -ENOENT;
2943 }
2944
2945 read_lock(&policy_rwlock);
2946
2947 if (rule->au_seqno < latest_granting) {
2948 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2949 "selinux_audit_rule_match: stale rule\n");
2950 match = -ESTALE;
2951 goto out;
2952 }
2953
2954 ctxt = sidtab_search(&sidtab, sid);
2955 if (!ctxt) {
2956 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2957 "selinux_audit_rule_match: unrecognized SID %d\n",
2958 sid);
2959 match = -ENOENT;
2960 goto out;
2961 }
2962
2963 /* a field/op pair that is not caught here will simply fall through
2964 without a match */
2965 switch (field) {
2966 case AUDIT_SUBJ_USER:
2967 case AUDIT_OBJ_USER:
2968 switch (op) {
2969 case Audit_equal:
2970 match = (ctxt->user == rule->au_ctxt.user);
2971 break;
2972 case Audit_not_equal:
2973 match = (ctxt->user != rule->au_ctxt.user);
2974 break;
2975 }
2976 break;
2977 case AUDIT_SUBJ_ROLE:
2978 case AUDIT_OBJ_ROLE:
2979 switch (op) {
2980 case Audit_equal:
2981 match = (ctxt->role == rule->au_ctxt.role);
2982 break;
2983 case Audit_not_equal:
2984 match = (ctxt->role != rule->au_ctxt.role);
2985 break;
2986 }
2987 break;
2988 case AUDIT_SUBJ_TYPE:
2989 case AUDIT_OBJ_TYPE:
2990 switch (op) {
2991 case Audit_equal:
2992 match = (ctxt->type == rule->au_ctxt.type);
2993 break;
2994 case Audit_not_equal:
2995 match = (ctxt->type != rule->au_ctxt.type);
2996 break;
2997 }
2998 break;
2999 case AUDIT_SUBJ_SEN:
3000 case AUDIT_SUBJ_CLR:
3001 case AUDIT_OBJ_LEV_LOW:
3002 case AUDIT_OBJ_LEV_HIGH:
3003 level = ((field == AUDIT_SUBJ_SEN ||
3004 field == AUDIT_OBJ_LEV_LOW) ?
3005 &ctxt->range.level[0] : &ctxt->range.level[1]);
3006 switch (op) {
3007 case Audit_equal:
3008 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3009 level);
3010 break;
3011 case Audit_not_equal:
3012 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3013 level);
3014 break;
3015 case Audit_lt:
3016 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3017 level) &&
3018 !mls_level_eq(&rule->au_ctxt.range.level[0],
3019 level));
3020 break;
3021 case Audit_le:
3022 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3023 level);
3024 break;
3025 case Audit_gt:
3026 match = (mls_level_dom(level,
3027 &rule->au_ctxt.range.level[0]) &&
3028 !mls_level_eq(level,
3029 &rule->au_ctxt.range.level[0]));
3030 break;
3031 case Audit_ge:
3032 match = mls_level_dom(level,
3033 &rule->au_ctxt.range.level[0]);
3034 break;
3035 }
3036 }
3037
3038 out:
3039 read_unlock(&policy_rwlock);
3040 return match;
3041 }
3042
3043 static int (*aurule_callback)(void) = audit_update_lsm_rules;
3044
3045 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
3046 u16 class, u32 perms, u32 *retained)
3047 {
3048 int err = 0;
3049
3050 if (event == AVC_CALLBACK_RESET && aurule_callback)
3051 err = aurule_callback();
3052 return err;
3053 }
3054
3055 static int __init aurule_init(void)
3056 {
3057 int err;
3058
3059 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
3060 SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
3061 if (err)
3062 panic("avc_add_callback() failed, error %d\n", err);
3063
3064 return err;
3065 }
3066 __initcall(aurule_init);
3067
3068 #ifdef CONFIG_NETLABEL
3069 /**
3070 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3071 * @secattr: the NetLabel packet security attributes
3072 * @sid: the SELinux SID
3073 *
3074 * Description:
3075 * Attempt to cache the context in @ctx, which was derived from the packet in
3076 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3077 * already been initialized.
3078 *
3079 */
3080 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3081 u32 sid)
3082 {
3083 u32 *sid_cache;
3084
3085 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3086 if (sid_cache == NULL)
3087 return;
3088 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3089 if (secattr->cache == NULL) {
3090 kfree(sid_cache);
3091 return;
3092 }
3093
3094 *sid_cache = sid;
3095 secattr->cache->free = kfree;
3096 secattr->cache->data = sid_cache;
3097 secattr->flags |= NETLBL_SECATTR_CACHE;
3098 }
3099
3100 /**
3101 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3102 * @secattr: the NetLabel packet security attributes
3103 * @sid: the SELinux SID
3104 *
3105 * Description:
3106 * Convert the given NetLabel security attributes in @secattr into a
3107 * SELinux SID. If the @secattr field does not contain a full SELinux
3108 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3109 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3110 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3111 * conversion for future lookups. Returns zero on success, negative values on
3112 * failure.
3113 *
3114 */
3115 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3116 u32 *sid)
3117 {
3118 int rc;
3119 struct context *ctx;
3120 struct context ctx_new;
3121
3122 if (!ss_initialized) {
3123 *sid = SECSID_NULL;
3124 return 0;
3125 }
3126
3127 read_lock(&policy_rwlock);
3128
3129 if (secattr->flags & NETLBL_SECATTR_CACHE)
3130 *sid = *(u32 *)secattr->cache->data;
3131 else if (secattr->flags & NETLBL_SECATTR_SECID)
3132 *sid = secattr->attr.secid;
3133 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3134 rc = -EIDRM;
3135 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3136 if (ctx == NULL)
3137 goto out;
3138
3139 context_init(&ctx_new);
3140 ctx_new.user = ctx->user;
3141 ctx_new.role = ctx->role;
3142 ctx_new.type = ctx->type;
3143 mls_import_netlbl_lvl(&ctx_new, secattr);
3144 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3145 rc = ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
3146 secattr->attr.mls.cat);
3147 if (rc)
3148 goto out;
3149 memcpy(&ctx_new.range.level[1].cat,
3150 &ctx_new.range.level[0].cat,
3151 sizeof(ctx_new.range.level[0].cat));
3152 }
3153 rc = -EIDRM;
3154 if (!mls_context_isvalid(&policydb, &ctx_new))
3155 goto out_free;
3156
3157 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3158 if (rc)
3159 goto out_free;
3160
3161 security_netlbl_cache_add(secattr, *sid);
3162
3163 ebitmap_destroy(&ctx_new.range.level[0].cat);
3164 } else
3165 *sid = SECSID_NULL;
3166
3167 read_unlock(&policy_rwlock);
3168 return 0;
3169 out_free:
3170 ebitmap_destroy(&ctx_new.range.level[0].cat);
3171 out:
3172 read_unlock(&policy_rwlock);
3173 return rc;
3174 }
3175
3176 /**
3177 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3178 * @sid: the SELinux SID
3179 * @secattr: the NetLabel packet security attributes
3180 *
3181 * Description:
3182 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3183 * Returns zero on success, negative values on failure.
3184 *
3185 */
3186 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3187 {
3188 int rc;
3189 struct context *ctx;
3190
3191 if (!ss_initialized)
3192 return 0;
3193
3194 read_lock(&policy_rwlock);
3195
3196 rc = -ENOENT;
3197 ctx = sidtab_search(&sidtab, sid);
3198 if (ctx == NULL)
3199 goto out;
3200
3201 rc = -ENOMEM;
3202 secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1),
3203 GFP_ATOMIC);
3204 if (secattr->domain == NULL)
3205 goto out;
3206
3207 secattr->attr.secid = sid;
3208 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3209 mls_export_netlbl_lvl(ctx, secattr);
3210 rc = mls_export_netlbl_cat(ctx, secattr);
3211 out:
3212 read_unlock(&policy_rwlock);
3213 return rc;
3214 }
3215 #endif /* CONFIG_NETLABEL */
3216
3217 /**
3218 * security_read_policy - read the policy.
3219 * @data: binary policy data
3220 * @len: length of data in bytes
3221 *
3222 */
3223 int security_read_policy(void **data, size_t *len)
3224 {
3225 int rc;
3226 struct policy_file fp;
3227
3228 if (!ss_initialized)
3229 return -EINVAL;
3230
3231 *len = security_policydb_len();
3232
3233 *data = vmalloc_user(*len);
3234 if (!*data)
3235 return -ENOMEM;
3236
3237 fp.data = *data;
3238 fp.len = *len;
3239
3240 read_lock(&policy_rwlock);
3241 rc = policydb_write(&policydb, &fp);
3242 read_unlock(&policy_rwlock);
3243
3244 if (rc)
3245 return rc;
3246
3247 *len = (unsigned long)fp.data - (unsigned long)*data;
3248 return 0;
3249
3250 }
kernel source for telekom puls (alcatel/mediatek)