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writeback: split writeback_inodes_wb
[linux-2.6/next.git] / security / selinux / ss / services.c
blob1de60ce90d9a237cd4cbfda6a4a34adb6c1de618
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.moore@hp.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 <net/netlabel.h>
54
55 #include "flask.h"
56 #include "avc.h"
57 #include "avc_ss.h"
58 #include "security.h"
59 #include "context.h"
60 #include "policydb.h"
61 #include "sidtab.h"
62 #include "services.h"
63 #include "conditional.h"
64 #include "mls.h"
65 #include "objsec.h"
66 #include "netlabel.h"
67 #include "xfrm.h"
68 #include "ebitmap.h"
69 #include "audit.h"
70
71 extern void selnl_notify_policyload(u32 seqno);
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 static void map_decision(u16 tclass, struct av_decision *avd,
203 int allow_unknown)
204 {
205 if (tclass < current_mapping_size) {
206 unsigned i, n = current_mapping[tclass].num_perms;
207 u32 result;
208
209 for (i = 0, result = 0; i < n; i++) {
210 if (avd->allowed & current_mapping[tclass].perms[i])
211 result |= 1<<i;
212 if (allow_unknown && !current_mapping[tclass].perms[i])
213 result |= 1<<i;
214 }
215 avd->allowed = result;
216
217 for (i = 0, result = 0; i < n; i++)
218 if (avd->auditallow & current_mapping[tclass].perms[i])
219 result |= 1<<i;
220 avd->auditallow = result;
221
222 for (i = 0, result = 0; i < n; i++) {
223 if (avd->auditdeny & current_mapping[tclass].perms[i])
224 result |= 1<<i;
225 if (!allow_unknown && !current_mapping[tclass].perms[i])
226 result |= 1<<i;
227 }
228 /*
229 * In case the kernel has a bug and requests a permission
230 * between num_perms and the maximum permission number, we
231 * should audit that denial
232 */
233 for (; i < (sizeof(u32)*8); i++)
234 result |= 1<<i;
235 avd->auditdeny = result;
236 }
237 }
238
239 int security_mls_enabled(void)
240 {
241 return policydb.mls_enabled;
242 }
243
244 /*
245 * Return the boolean value of a constraint expression
246 * when it is applied to the specified source and target
247 * security contexts.
248 *
249 * xcontext is a special beast... It is used by the validatetrans rules
250 * only. For these rules, scontext is the context before the transition,
251 * tcontext is the context after the transition, and xcontext is the context
252 * of the process performing the transition. All other callers of
253 * constraint_expr_eval should pass in NULL for xcontext.
254 */
255 static int constraint_expr_eval(struct context *scontext,
256 struct context *tcontext,
257 struct context *xcontext,
258 struct constraint_expr *cexpr)
259 {
260 u32 val1, val2;
261 struct context *c;
262 struct role_datum *r1, *r2;
263 struct mls_level *l1, *l2;
264 struct constraint_expr *e;
265 int s[CEXPR_MAXDEPTH];
266 int sp = -1;
267
268 for (e = cexpr; e; e = e->next) {
269 switch (e->expr_type) {
270 case CEXPR_NOT:
271 BUG_ON(sp < 0);
272 s[sp] = !s[sp];
273 break;
274 case CEXPR_AND:
275 BUG_ON(sp < 1);
276 sp--;
277 s[sp] &= s[sp + 1];
278 break;
279 case CEXPR_OR:
280 BUG_ON(sp < 1);
281 sp--;
282 s[sp] |= s[sp + 1];
283 break;
284 case CEXPR_ATTR:
285 if (sp == (CEXPR_MAXDEPTH - 1))
286 return 0;
287 switch (e->attr) {
288 case CEXPR_USER:
289 val1 = scontext->user;
290 val2 = tcontext->user;
291 break;
292 case CEXPR_TYPE:
293 val1 = scontext->type;
294 val2 = tcontext->type;
295 break;
296 case CEXPR_ROLE:
297 val1 = scontext->role;
298 val2 = tcontext->role;
299 r1 = policydb.role_val_to_struct[val1 - 1];
300 r2 = policydb.role_val_to_struct[val2 - 1];
301 switch (e->op) {
302 case CEXPR_DOM:
303 s[++sp] = ebitmap_get_bit(&r1->dominates,
304 val2 - 1);
305 continue;
306 case CEXPR_DOMBY:
307 s[++sp] = ebitmap_get_bit(&r2->dominates,
308 val1 - 1);
309 continue;
310 case CEXPR_INCOMP:
311 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
312 val2 - 1) &&
313 !ebitmap_get_bit(&r2->dominates,
314 val1 - 1));
315 continue;
316 default:
317 break;
318 }
319 break;
320 case CEXPR_L1L2:
321 l1 = &(scontext->range.level[0]);
322 l2 = &(tcontext->range.level[0]);
323 goto mls_ops;
324 case CEXPR_L1H2:
325 l1 = &(scontext->range.level[0]);
326 l2 = &(tcontext->range.level[1]);
327 goto mls_ops;
328 case CEXPR_H1L2:
329 l1 = &(scontext->range.level[1]);
330 l2 = &(tcontext->range.level[0]);
331 goto mls_ops;
332 case CEXPR_H1H2:
333 l1 = &(scontext->range.level[1]);
334 l2 = &(tcontext->range.level[1]);
335 goto mls_ops;
336 case CEXPR_L1H1:
337 l1 = &(scontext->range.level[0]);
338 l2 = &(scontext->range.level[1]);
339 goto mls_ops;
340 case CEXPR_L2H2:
341 l1 = &(tcontext->range.level[0]);
342 l2 = &(tcontext->range.level[1]);
343 goto mls_ops;
344 mls_ops:
345 switch (e->op) {
346 case CEXPR_EQ:
347 s[++sp] = mls_level_eq(l1, l2);
348 continue;
349 case CEXPR_NEQ:
350 s[++sp] = !mls_level_eq(l1, l2);
351 continue;
352 case CEXPR_DOM:
353 s[++sp] = mls_level_dom(l1, l2);
354 continue;
355 case CEXPR_DOMBY:
356 s[++sp] = mls_level_dom(l2, l1);
357 continue;
358 case CEXPR_INCOMP:
359 s[++sp] = mls_level_incomp(l2, l1);
360 continue;
361 default:
362 BUG();
363 return 0;
364 }
365 break;
366 default:
367 BUG();
368 return 0;
369 }
370
371 switch (e->op) {
372 case CEXPR_EQ:
373 s[++sp] = (val1 == val2);
374 break;
375 case CEXPR_NEQ:
376 s[++sp] = (val1 != val2);
377 break;
378 default:
379 BUG();
380 return 0;
381 }
382 break;
383 case CEXPR_NAMES:
384 if (sp == (CEXPR_MAXDEPTH-1))
385 return 0;
386 c = scontext;
387 if (e->attr & CEXPR_TARGET)
388 c = tcontext;
389 else if (e->attr & CEXPR_XTARGET) {
390 c = xcontext;
391 if (!c) {
392 BUG();
393 return 0;
394 }
395 }
396 if (e->attr & CEXPR_USER)
397 val1 = c->user;
398 else if (e->attr & CEXPR_ROLE)
399 val1 = c->role;
400 else if (e->attr & CEXPR_TYPE)
401 val1 = c->type;
402 else {
403 BUG();
404 return 0;
405 }
406
407 switch (e->op) {
408 case CEXPR_EQ:
409 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
410 break;
411 case CEXPR_NEQ:
412 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
413 break;
414 default:
415 BUG();
416 return 0;
417 }
418 break;
419 default:
420 BUG();
421 return 0;
422 }
423 }
424
425 BUG_ON(sp != 0);
426 return s[0];
427 }
428
429 /*
430 * security_dump_masked_av - dumps masked permissions during
431 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
432 */
433 static int dump_masked_av_helper(void *k, void *d, void *args)
434 {
435 struct perm_datum *pdatum = d;
436 char **permission_names = args;
437
438 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
439
440 permission_names[pdatum->value - 1] = (char *)k;
441
442 return 0;
443 }
444
445 static void security_dump_masked_av(struct context *scontext,
446 struct context *tcontext,
447 u16 tclass,
448 u32 permissions,
449 const char *reason)
450 {
451 struct common_datum *common_dat;
452 struct class_datum *tclass_dat;
453 struct audit_buffer *ab;
454 char *tclass_name;
455 char *scontext_name = NULL;
456 char *tcontext_name = NULL;
457 char *permission_names[32];
458 int index;
459 u32 length;
460 bool need_comma = false;
461
462 if (!permissions)
463 return;
464
465 tclass_name = policydb.p_class_val_to_name[tclass - 1];
466 tclass_dat = policydb.class_val_to_struct[tclass - 1];
467 common_dat = tclass_dat->comdatum;
468
469 /* init permission_names */
470 if (common_dat &&
471 hashtab_map(common_dat->permissions.table,
472 dump_masked_av_helper, permission_names) < 0)
473 goto out;
474
475 if (hashtab_map(tclass_dat->permissions.table,
476 dump_masked_av_helper, permission_names) < 0)
477 goto out;
478
479 /* get scontext/tcontext in text form */
480 if (context_struct_to_string(scontext,
481 &scontext_name, &length) < 0)
482 goto out;
483
484 if (context_struct_to_string(tcontext,
485 &tcontext_name, &length) < 0)
486 goto out;
487
488 /* audit a message */
489 ab = audit_log_start(current->audit_context,
490 GFP_ATOMIC, AUDIT_SELINUX_ERR);
491 if (!ab)
492 goto out;
493
494 audit_log_format(ab, "op=security_compute_av reason=%s "
495 "scontext=%s tcontext=%s tclass=%s perms=",
496 reason, scontext_name, tcontext_name, tclass_name);
497
498 for (index = 0; index < 32; index++) {
499 u32 mask = (1 << index);
500
501 if ((mask & permissions) == 0)
502 continue;
503
504 audit_log_format(ab, "%s%s",
505 need_comma ? "," : "",
506 permission_names[index]
507 ? permission_names[index] : "????");
508 need_comma = true;
509 }
510 audit_log_end(ab);
511 out:
512 /* release scontext/tcontext */
513 kfree(tcontext_name);
514 kfree(scontext_name);
515
516 return;
517 }
518
519 /*
520 * security_boundary_permission - drops violated permissions
521 * on boundary constraint.
522 */
523 static void type_attribute_bounds_av(struct context *scontext,
524 struct context *tcontext,
525 u16 tclass,
526 struct av_decision *avd)
527 {
528 struct context lo_scontext;
529 struct context lo_tcontext;
530 struct av_decision lo_avd;
531 struct type_datum *source
532 = policydb.type_val_to_struct[scontext->type - 1];
533 struct type_datum *target
534 = policydb.type_val_to_struct[tcontext->type - 1];
535 u32 masked = 0;
536
537 if (source->bounds) {
538 memset(&lo_avd, 0, sizeof(lo_avd));
539
540 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
541 lo_scontext.type = source->bounds;
542
543 context_struct_compute_av(&lo_scontext,
544 tcontext,
545 tclass,
546 &lo_avd);
547 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
548 return; /* no masked permission */
549 masked = ~lo_avd.allowed & avd->allowed;
550 }
551
552 if (target->bounds) {
553 memset(&lo_avd, 0, sizeof(lo_avd));
554
555 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
556 lo_tcontext.type = target->bounds;
557
558 context_struct_compute_av(scontext,
559 &lo_tcontext,
560 tclass,
561 &lo_avd);
562 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
563 return; /* no masked permission */
564 masked = ~lo_avd.allowed & avd->allowed;
565 }
566
567 if (source->bounds && target->bounds) {
568 memset(&lo_avd, 0, sizeof(lo_avd));
569 /*
570 * lo_scontext and lo_tcontext are already
571 * set up.
572 */
573
574 context_struct_compute_av(&lo_scontext,
575 &lo_tcontext,
576 tclass,
577 &lo_avd);
578 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
579 return; /* no masked permission */
580 masked = ~lo_avd.allowed & avd->allowed;
581 }
582
583 if (masked) {
584 /* mask violated permissions */
585 avd->allowed &= ~masked;
586
587 /* audit masked permissions */
588 security_dump_masked_av(scontext, tcontext,
589 tclass, masked, "bounds");
590 }
591 }
592
593 /*
594 * Compute access vectors based on a context structure pair for
595 * the permissions in a particular class.
596 */
597 static void context_struct_compute_av(struct context *scontext,
598 struct context *tcontext,
599 u16 tclass,
600 struct av_decision *avd)
601 {
602 struct constraint_node *constraint;
603 struct role_allow *ra;
604 struct avtab_key avkey;
605 struct avtab_node *node;
606 struct class_datum *tclass_datum;
607 struct ebitmap *sattr, *tattr;
608 struct ebitmap_node *snode, *tnode;
609 unsigned int i, j;
610
611 avd->allowed = 0;
612 avd->auditallow = 0;
613 avd->auditdeny = 0xffffffff;
614
615 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
616 if (printk_ratelimit())
617 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass);
618 return;
619 }
620
621 tclass_datum = policydb.class_val_to_struct[tclass - 1];
622
623 /*
624 * If a specific type enforcement rule was defined for
625 * this permission check, then use it.
626 */
627 avkey.target_class = tclass;
628 avkey.specified = AVTAB_AV;
629 sattr = &policydb.type_attr_map[scontext->type - 1];
630 tattr = &policydb.type_attr_map[tcontext->type - 1];
631 ebitmap_for_each_positive_bit(sattr, snode, i) {
632 ebitmap_for_each_positive_bit(tattr, tnode, j) {
633 avkey.source_type = i + 1;
634 avkey.target_type = j + 1;
635 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
636 node;
637 node = avtab_search_node_next(node, avkey.specified)) {
638 if (node->key.specified == AVTAB_ALLOWED)
639 avd->allowed |= node->datum.data;
640 else if (node->key.specified == AVTAB_AUDITALLOW)
641 avd->auditallow |= node->datum.data;
642 else if (node->key.specified == AVTAB_AUDITDENY)
643 avd->auditdeny &= node->datum.data;
644 }
645
646 /* Check conditional av table for additional permissions */
647 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
648
649 }
650 }
651
652 /*
653 * Remove any permissions prohibited by a constraint (this includes
654 * the MLS policy).
655 */
656 constraint = tclass_datum->constraints;
657 while (constraint) {
658 if ((constraint->permissions & (avd->allowed)) &&
659 !constraint_expr_eval(scontext, tcontext, NULL,
660 constraint->expr)) {
661 avd->allowed &= ~(constraint->permissions);
662 }
663 constraint = constraint->next;
664 }
665
666 /*
667 * If checking process transition permission and the
668 * role is changing, then check the (current_role, new_role)
669 * pair.
670 */
671 if (tclass == policydb.process_class &&
672 (avd->allowed & policydb.process_trans_perms) &&
673 scontext->role != tcontext->role) {
674 for (ra = policydb.role_allow; ra; ra = ra->next) {
675 if (scontext->role == ra->role &&
676 tcontext->role == ra->new_role)
677 break;
678 }
679 if (!ra)
680 avd->allowed &= ~policydb.process_trans_perms;
681 }
682
683 /*
684 * If the given source and target types have boundary
685 * constraint, lazy checks have to mask any violated
686 * permission and notice it to userspace via audit.
687 */
688 type_attribute_bounds_av(scontext, tcontext,
689 tclass, avd);
690 }
691
692 static int security_validtrans_handle_fail(struct context *ocontext,
693 struct context *ncontext,
694 struct context *tcontext,
695 u16 tclass)
696 {
697 char *o = NULL, *n = NULL, *t = NULL;
698 u32 olen, nlen, tlen;
699
700 if (context_struct_to_string(ocontext, &o, &olen) < 0)
701 goto out;
702 if (context_struct_to_string(ncontext, &n, &nlen) < 0)
703 goto out;
704 if (context_struct_to_string(tcontext, &t, &tlen) < 0)
705 goto out;
706 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
707 "security_validate_transition: denied for"
708 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
709 o, n, t, policydb.p_class_val_to_name[tclass-1]);
710 out:
711 kfree(o);
712 kfree(n);
713 kfree(t);
714
715 if (!selinux_enforcing)
716 return 0;
717 return -EPERM;
718 }
719
720 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
721 u16 orig_tclass)
722 {
723 struct context *ocontext;
724 struct context *ncontext;
725 struct context *tcontext;
726 struct class_datum *tclass_datum;
727 struct constraint_node *constraint;
728 u16 tclass;
729 int rc = 0;
730
731 if (!ss_initialized)
732 return 0;
733
734 read_lock(&policy_rwlock);
735
736 tclass = unmap_class(orig_tclass);
737
738 if (!tclass || tclass > policydb.p_classes.nprim) {
739 printk(KERN_ERR "SELinux: %s: unrecognized class %d\n",
740 __func__, tclass);
741 rc = -EINVAL;
742 goto out;
743 }
744 tclass_datum = policydb.class_val_to_struct[tclass - 1];
745
746 ocontext = sidtab_search(&sidtab, oldsid);
747 if (!ocontext) {
748 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
749 __func__, oldsid);
750 rc = -EINVAL;
751 goto out;
752 }
753
754 ncontext = sidtab_search(&sidtab, newsid);
755 if (!ncontext) {
756 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
757 __func__, newsid);
758 rc = -EINVAL;
759 goto out;
760 }
761
762 tcontext = sidtab_search(&sidtab, tasksid);
763 if (!tcontext) {
764 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
765 __func__, tasksid);
766 rc = -EINVAL;
767 goto out;
768 }
769
770 constraint = tclass_datum->validatetrans;
771 while (constraint) {
772 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
773 constraint->expr)) {
774 rc = security_validtrans_handle_fail(ocontext, ncontext,
775 tcontext, tclass);
776 goto out;
777 }
778 constraint = constraint->next;
779 }
780
781 out:
782 read_unlock(&policy_rwlock);
783 return rc;
784 }
785
786 /*
787 * security_bounded_transition - check whether the given
788 * transition is directed to bounded, or not.
789 * It returns 0, if @newsid is bounded by @oldsid.
790 * Otherwise, it returns error code.
791 *
792 * @oldsid : current security identifier
793 * @newsid : destinated security identifier
794 */
795 int security_bounded_transition(u32 old_sid, u32 new_sid)
796 {
797 struct context *old_context, *new_context;
798 struct type_datum *type;
799 int index;
800 int rc = -EINVAL;
801
802 read_lock(&policy_rwlock);
803
804 old_context = sidtab_search(&sidtab, old_sid);
805 if (!old_context) {
806 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
807 __func__, old_sid);
808 goto out;
809 }
810
811 new_context = sidtab_search(&sidtab, new_sid);
812 if (!new_context) {
813 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
814 __func__, new_sid);
815 goto out;
816 }
817
818 /* type/domain unchanged */
819 if (old_context->type == new_context->type) {
820 rc = 0;
821 goto out;
822 }
823
824 index = new_context->type;
825 while (true) {
826 type = policydb.type_val_to_struct[index - 1];
827 BUG_ON(!type);
828
829 /* not bounded anymore */
830 if (!type->bounds) {
831 rc = -EPERM;
832 break;
833 }
834
835 /* @newsid is bounded by @oldsid */
836 if (type->bounds == old_context->type) {
837 rc = 0;
838 break;
839 }
840 index = type->bounds;
841 }
842
843 if (rc) {
844 char *old_name = NULL;
845 char *new_name = NULL;
846 u32 length;
847
848 if (!context_struct_to_string(old_context,
849 &old_name, &length) &&
850 !context_struct_to_string(new_context,
851 &new_name, &length)) {
852 audit_log(current->audit_context,
853 GFP_ATOMIC, AUDIT_SELINUX_ERR,
854 "op=security_bounded_transition "
855 "result=denied "
856 "oldcontext=%s newcontext=%s",
857 old_name, new_name);
858 }
859 kfree(new_name);
860 kfree(old_name);
861 }
862 out:
863 read_unlock(&policy_rwlock);
864
865 return rc;
866 }
867
868 static void avd_init(struct av_decision *avd)
869 {
870 avd->allowed = 0;
871 avd->auditallow = 0;
872 avd->auditdeny = 0xffffffff;
873 avd->seqno = latest_granting;
874 avd->flags = 0;
875 }
876
877
878 /**
879 * security_compute_av - Compute access vector decisions.
880 * @ssid: source security identifier
881 * @tsid: target security identifier
882 * @tclass: target security class
883 * @avd: access vector decisions
884 *
885 * Compute a set of access vector decisions based on the
886 * SID pair (@ssid, @tsid) for the permissions in @tclass.
887 */
888 void security_compute_av(u32 ssid,
889 u32 tsid,
890 u16 orig_tclass,
891 struct av_decision *avd)
892 {
893 u16 tclass;
894 struct context *scontext = NULL, *tcontext = NULL;
895
896 read_lock(&policy_rwlock);
897 avd_init(avd);
898 if (!ss_initialized)
899 goto allow;
900
901 scontext = sidtab_search(&sidtab, ssid);
902 if (!scontext) {
903 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
904 __func__, ssid);
905 goto out;
906 }
907
908 /* permissive domain? */
909 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
910 avd->flags |= AVD_FLAGS_PERMISSIVE;
911
912 tcontext = sidtab_search(&sidtab, tsid);
913 if (!tcontext) {
914 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
915 __func__, tsid);
916 goto out;
917 }
918
919 tclass = unmap_class(orig_tclass);
920 if (unlikely(orig_tclass && !tclass)) {
921 if (policydb.allow_unknown)
922 goto allow;
923 goto out;
924 }
925 context_struct_compute_av(scontext, tcontext, tclass, avd);
926 map_decision(orig_tclass, avd, policydb.allow_unknown);
927 out:
928 read_unlock(&policy_rwlock);
929 return;
930 allow:
931 avd->allowed = 0xffffffff;
932 goto out;
933 }
934
935 void security_compute_av_user(u32 ssid,
936 u32 tsid,
937 u16 tclass,
938 struct av_decision *avd)
939 {
940 struct context *scontext = NULL, *tcontext = NULL;
941
942 read_lock(&policy_rwlock);
943 avd_init(avd);
944 if (!ss_initialized)
945 goto allow;
946
947 scontext = sidtab_search(&sidtab, ssid);
948 if (!scontext) {
949 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
950 __func__, ssid);
951 goto out;
952 }
953
954 /* permissive domain? */
955 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
956 avd->flags |= AVD_FLAGS_PERMISSIVE;
957
958 tcontext = sidtab_search(&sidtab, tsid);
959 if (!tcontext) {
960 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
961 __func__, tsid);
962 goto out;
963 }
964
965 if (unlikely(!tclass)) {
966 if (policydb.allow_unknown)
967 goto allow;
968 goto out;
969 }
970
971 context_struct_compute_av(scontext, tcontext, tclass, avd);
972 out:
973 read_unlock(&policy_rwlock);
974 return;
975 allow:
976 avd->allowed = 0xffffffff;
977 goto out;
978 }
979
980 /*
981 * Write the security context string representation of
982 * the context structure `context' into a dynamically
983 * allocated string of the correct size. Set `*scontext'
984 * to point to this string and set `*scontext_len' to
985 * the length of the string.
986 */
987 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
988 {
989 char *scontextp;
990
991 *scontext = NULL;
992 *scontext_len = 0;
993
994 if (context->len) {
995 *scontext_len = context->len;
996 *scontext = kstrdup(context->str, GFP_ATOMIC);
997 if (!(*scontext))
998 return -ENOMEM;
999 return 0;
1000 }
1001
1002 /* Compute the size of the context. */
1003 *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
1004 *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
1005 *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
1006 *scontext_len += mls_compute_context_len(context);
1007
1008 /* Allocate space for the context; caller must free this space. */
1009 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1010 if (!scontextp)
1011 return -ENOMEM;
1012 *scontext = scontextp;
1013
1014 /*
1015 * Copy the user name, role name and type name into the context.
1016 */
1017 sprintf(scontextp, "%s:%s:%s",
1018 policydb.p_user_val_to_name[context->user - 1],
1019 policydb.p_role_val_to_name[context->role - 1],
1020 policydb.p_type_val_to_name[context->type - 1]);
1021 scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
1022 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
1023 1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
1024
1025 mls_sid_to_context(context, &scontextp);
1026
1027 *scontextp = 0;
1028
1029 return 0;
1030 }
1031
1032 #include "initial_sid_to_string.h"
1033
1034 const char *security_get_initial_sid_context(u32 sid)
1035 {
1036 if (unlikely(sid > SECINITSID_NUM))
1037 return NULL;
1038 return initial_sid_to_string[sid];
1039 }
1040
1041 static int security_sid_to_context_core(u32 sid, char **scontext,
1042 u32 *scontext_len, int force)
1043 {
1044 struct context *context;
1045 int rc = 0;
1046
1047 *scontext = NULL;
1048 *scontext_len = 0;
1049
1050 if (!ss_initialized) {
1051 if (sid <= SECINITSID_NUM) {
1052 char *scontextp;
1053
1054 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1055 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1056 if (!scontextp) {
1057 rc = -ENOMEM;
1058 goto out;
1059 }
1060 strcpy(scontextp, initial_sid_to_string[sid]);
1061 *scontext = scontextp;
1062 goto out;
1063 }
1064 printk(KERN_ERR "SELinux: %s: called before initial "
1065 "load_policy on unknown SID %d\n", __func__, sid);
1066 rc = -EINVAL;
1067 goto out;
1068 }
1069 read_lock(&policy_rwlock);
1070 if (force)
1071 context = sidtab_search_force(&sidtab, sid);
1072 else
1073 context = sidtab_search(&sidtab, sid);
1074 if (!context) {
1075 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1076 __func__, sid);
1077 rc = -EINVAL;
1078 goto out_unlock;
1079 }
1080 rc = context_struct_to_string(context, scontext, scontext_len);
1081 out_unlock:
1082 read_unlock(&policy_rwlock);
1083 out:
1084 return rc;
1085
1086 }
1087
1088 /**
1089 * security_sid_to_context - Obtain a context for a given SID.
1090 * @sid: security identifier, SID
1091 * @scontext: security context
1092 * @scontext_len: length in bytes
1093 *
1094 * Write the string representation of the context associated with @sid
1095 * into a dynamically allocated string of the correct size. Set @scontext
1096 * to point to this string and set @scontext_len to the length of the string.
1097 */
1098 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1099 {
1100 return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1101 }
1102
1103 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1104 {
1105 return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1106 }
1107
1108 /*
1109 * Caveat: Mutates scontext.
1110 */
1111 static int string_to_context_struct(struct policydb *pol,
1112 struct sidtab *sidtabp,
1113 char *scontext,
1114 u32 scontext_len,
1115 struct context *ctx,
1116 u32 def_sid)
1117 {
1118 struct role_datum *role;
1119 struct type_datum *typdatum;
1120 struct user_datum *usrdatum;
1121 char *scontextp, *p, oldc;
1122 int rc = 0;
1123
1124 context_init(ctx);
1125
1126 /* Parse the security context. */
1127
1128 rc = -EINVAL;
1129 scontextp = (char *) scontext;
1130
1131 /* Extract the user. */
1132 p = scontextp;
1133 while (*p && *p != ':')
1134 p++;
1135
1136 if (*p == 0)
1137 goto out;
1138
1139 *p++ = 0;
1140
1141 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1142 if (!usrdatum)
1143 goto out;
1144
1145 ctx->user = usrdatum->value;
1146
1147 /* Extract role. */
1148 scontextp = p;
1149 while (*p && *p != ':')
1150 p++;
1151
1152 if (*p == 0)
1153 goto out;
1154
1155 *p++ = 0;
1156
1157 role = hashtab_search(pol->p_roles.table, scontextp);
1158 if (!role)
1159 goto out;
1160 ctx->role = role->value;
1161
1162 /* Extract type. */
1163 scontextp = p;
1164 while (*p && *p != ':')
1165 p++;
1166 oldc = *p;
1167 *p++ = 0;
1168
1169 typdatum = hashtab_search(pol->p_types.table, scontextp);
1170 if (!typdatum || typdatum->attribute)
1171 goto out;
1172
1173 ctx->type = typdatum->value;
1174
1175 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1176 if (rc)
1177 goto out;
1178
1179 if ((p - scontext) < scontext_len) {
1180 rc = -EINVAL;
1181 goto out;
1182 }
1183
1184 /* Check the validity of the new context. */
1185 if (!policydb_context_isvalid(pol, ctx)) {
1186 rc = -EINVAL;
1187 goto out;
1188 }
1189 rc = 0;
1190 out:
1191 if (rc)
1192 context_destroy(ctx);
1193 return rc;
1194 }
1195
1196 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1197 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1198 int force)
1199 {
1200 char *scontext2, *str = NULL;
1201 struct context context;
1202 int rc = 0;
1203
1204 if (!ss_initialized) {
1205 int i;
1206
1207 for (i = 1; i < SECINITSID_NUM; i++) {
1208 if (!strcmp(initial_sid_to_string[i], scontext)) {
1209 *sid = i;
1210 return 0;
1211 }
1212 }
1213 *sid = SECINITSID_KERNEL;
1214 return 0;
1215 }
1216 *sid = SECSID_NULL;
1217
1218 /* Copy the string so that we can modify the copy as we parse it. */
1219 scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1220 if (!scontext2)
1221 return -ENOMEM;
1222 memcpy(scontext2, scontext, scontext_len);
1223 scontext2[scontext_len] = 0;
1224
1225 if (force) {
1226 /* Save another copy for storing in uninterpreted form */
1227 str = kstrdup(scontext2, gfp_flags);
1228 if (!str) {
1229 kfree(scontext2);
1230 return -ENOMEM;
1231 }
1232 }
1233
1234 read_lock(&policy_rwlock);
1235 rc = string_to_context_struct(&policydb, &sidtab,
1236 scontext2, scontext_len,
1237 &context, def_sid);
1238 if (rc == -EINVAL && force) {
1239 context.str = str;
1240 context.len = scontext_len;
1241 str = NULL;
1242 } else if (rc)
1243 goto out;
1244 rc = sidtab_context_to_sid(&sidtab, &context, sid);
1245 context_destroy(&context);
1246 out:
1247 read_unlock(&policy_rwlock);
1248 kfree(scontext2);
1249 kfree(str);
1250 return rc;
1251 }
1252
1253 /**
1254 * security_context_to_sid - Obtain a SID for a given security context.
1255 * @scontext: security context
1256 * @scontext_len: length in bytes
1257 * @sid: security identifier, SID
1258 *
1259 * Obtains a SID associated with the security context that
1260 * has the string representation specified by @scontext.
1261 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1262 * memory is available, or 0 on success.
1263 */
1264 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
1265 {
1266 return security_context_to_sid_core(scontext, scontext_len,
1267 sid, SECSID_NULL, GFP_KERNEL, 0);
1268 }
1269
1270 /**
1271 * security_context_to_sid_default - Obtain a SID for a given security context,
1272 * falling back to specified default if needed.
1273 *
1274 * @scontext: security context
1275 * @scontext_len: length in bytes
1276 * @sid: security identifier, SID
1277 * @def_sid: default SID to assign on error
1278 *
1279 * Obtains a SID associated with the security context that
1280 * has the string representation specified by @scontext.
1281 * The default SID is passed to the MLS layer to be used to allow
1282 * kernel labeling of the MLS field if the MLS field is not present
1283 * (for upgrading to MLS without full relabel).
1284 * Implicitly forces adding of the context even if it cannot be mapped yet.
1285 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1286 * memory is available, or 0 on success.
1287 */
1288 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1289 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1290 {
1291 return security_context_to_sid_core(scontext, scontext_len,
1292 sid, def_sid, gfp_flags, 1);
1293 }
1294
1295 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1296 u32 *sid)
1297 {
1298 return security_context_to_sid_core(scontext, scontext_len,
1299 sid, SECSID_NULL, GFP_KERNEL, 1);
1300 }
1301
1302 static int compute_sid_handle_invalid_context(
1303 struct context *scontext,
1304 struct context *tcontext,
1305 u16 tclass,
1306 struct context *newcontext)
1307 {
1308 char *s = NULL, *t = NULL, *n = NULL;
1309 u32 slen, tlen, nlen;
1310
1311 if (context_struct_to_string(scontext, &s, &slen) < 0)
1312 goto out;
1313 if (context_struct_to_string(tcontext, &t, &tlen) < 0)
1314 goto out;
1315 if (context_struct_to_string(newcontext, &n, &nlen) < 0)
1316 goto out;
1317 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1318 "security_compute_sid: invalid context %s"
1319 " for scontext=%s"
1320 " tcontext=%s"
1321 " tclass=%s",
1322 n, s, t, policydb.p_class_val_to_name[tclass-1]);
1323 out:
1324 kfree(s);
1325 kfree(t);
1326 kfree(n);
1327 if (!selinux_enforcing)
1328 return 0;
1329 return -EACCES;
1330 }
1331
1332 static int security_compute_sid(u32 ssid,
1333 u32 tsid,
1334 u16 orig_tclass,
1335 u32 specified,
1336 u32 *out_sid,
1337 bool kern)
1338 {
1339 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1340 struct role_trans *roletr = NULL;
1341 struct avtab_key avkey;
1342 struct avtab_datum *avdatum;
1343 struct avtab_node *node;
1344 u16 tclass;
1345 int rc = 0;
1346
1347 if (!ss_initialized) {
1348 switch (orig_tclass) {
1349 case SECCLASS_PROCESS: /* kernel value */
1350 *out_sid = ssid;
1351 break;
1352 default:
1353 *out_sid = tsid;
1354 break;
1355 }
1356 goto out;
1357 }
1358
1359 context_init(&newcontext);
1360
1361 read_lock(&policy_rwlock);
1362
1363 if (kern)
1364 tclass = unmap_class(orig_tclass);
1365 else
1366 tclass = orig_tclass;
1367
1368 scontext = sidtab_search(&sidtab, ssid);
1369 if (!scontext) {
1370 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1371 __func__, ssid);
1372 rc = -EINVAL;
1373 goto out_unlock;
1374 }
1375 tcontext = sidtab_search(&sidtab, tsid);
1376 if (!tcontext) {
1377 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1378 __func__, tsid);
1379 rc = -EINVAL;
1380 goto out_unlock;
1381 }
1382
1383 /* Set the user identity. */
1384 switch (specified) {
1385 case AVTAB_TRANSITION:
1386 case AVTAB_CHANGE:
1387 /* Use the process user identity. */
1388 newcontext.user = scontext->user;
1389 break;
1390 case AVTAB_MEMBER:
1391 /* Use the related object owner. */
1392 newcontext.user = tcontext->user;
1393 break;
1394 }
1395
1396 /* Set the role and type to default values. */
1397 if (tclass == policydb.process_class) {
1398 /* Use the current role and type of process. */
1399 newcontext.role = scontext->role;
1400 newcontext.type = scontext->type;
1401 } else {
1402 /* Use the well-defined object role. */
1403 newcontext.role = OBJECT_R_VAL;
1404 /* Use the type of the related object. */
1405 newcontext.type = tcontext->type;
1406 }
1407
1408 /* Look for a type transition/member/change rule. */
1409 avkey.source_type = scontext->type;
1410 avkey.target_type = tcontext->type;
1411 avkey.target_class = tclass;
1412 avkey.specified = specified;
1413 avdatum = avtab_search(&policydb.te_avtab, &avkey);
1414
1415 /* If no permanent rule, also check for enabled conditional rules */
1416 if (!avdatum) {
1417 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1418 for (; node; node = avtab_search_node_next(node, specified)) {
1419 if (node->key.specified & AVTAB_ENABLED) {
1420 avdatum = &node->datum;
1421 break;
1422 }
1423 }
1424 }
1425
1426 if (avdatum) {
1427 /* Use the type from the type transition/member/change rule. */
1428 newcontext.type = avdatum->data;
1429 }
1430
1431 /* Check for class-specific changes. */
1432 if (tclass == policydb.process_class) {
1433 if (specified & AVTAB_TRANSITION) {
1434 /* Look for a role transition rule. */
1435 for (roletr = policydb.role_tr; roletr;
1436 roletr = roletr->next) {
1437 if (roletr->role == scontext->role &&
1438 roletr->type == tcontext->type) {
1439 /* Use the role transition rule. */
1440 newcontext.role = roletr->new_role;
1441 break;
1442 }
1443 }
1444 }
1445 }
1446
1447 /* Set the MLS attributes.
1448 This is done last because it may allocate memory. */
1449 rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
1450 if (rc)
1451 goto out_unlock;
1452
1453 /* Check the validity of the context. */
1454 if (!policydb_context_isvalid(&policydb, &newcontext)) {
1455 rc = compute_sid_handle_invalid_context(scontext,
1456 tcontext,
1457 tclass,
1458 &newcontext);
1459 if (rc)
1460 goto out_unlock;
1461 }
1462 /* Obtain the sid for the context. */
1463 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1464 out_unlock:
1465 read_unlock(&policy_rwlock);
1466 context_destroy(&newcontext);
1467 out:
1468 return rc;
1469 }
1470
1471 /**
1472 * security_transition_sid - Compute the SID for a new subject/object.
1473 * @ssid: source security identifier
1474 * @tsid: target security identifier
1475 * @tclass: target security class
1476 * @out_sid: security identifier for new subject/object
1477 *
1478 * Compute a SID to use for labeling a new subject or object in the
1479 * class @tclass based on a SID pair (@ssid, @tsid).
1480 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1481 * if insufficient memory is available, or %0 if the new SID was
1482 * computed successfully.
1483 */
1484 int security_transition_sid(u32 ssid,
1485 u32 tsid,
1486 u16 tclass,
1487 u32 *out_sid)
1488 {
1489 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1490 out_sid, true);
1491 }
1492
1493 int security_transition_sid_user(u32 ssid,
1494 u32 tsid,
1495 u16 tclass,
1496 u32 *out_sid)
1497 {
1498 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1499 out_sid, false);
1500 }
1501
1502 /**
1503 * security_member_sid - Compute the SID for member selection.
1504 * @ssid: source security identifier
1505 * @tsid: target security identifier
1506 * @tclass: target security class
1507 * @out_sid: security identifier for selected member
1508 *
1509 * Compute a SID to use when selecting a member of a polyinstantiated
1510 * object of class @tclass based on a SID pair (@ssid, @tsid).
1511 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1512 * if insufficient memory is available, or %0 if the SID was
1513 * computed successfully.
1514 */
1515 int security_member_sid(u32 ssid,
1516 u32 tsid,
1517 u16 tclass,
1518 u32 *out_sid)
1519 {
1520 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid,
1521 false);
1522 }
1523
1524 /**
1525 * security_change_sid - Compute the SID for object relabeling.
1526 * @ssid: source security identifier
1527 * @tsid: target security identifier
1528 * @tclass: target security class
1529 * @out_sid: security identifier for selected member
1530 *
1531 * Compute a SID to use for relabeling an object of class @tclass
1532 * based on a SID pair (@ssid, @tsid).
1533 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1534 * if insufficient memory is available, or %0 if the SID was
1535 * computed successfully.
1536 */
1537 int security_change_sid(u32 ssid,
1538 u32 tsid,
1539 u16 tclass,
1540 u32 *out_sid)
1541 {
1542 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid,
1543 false);
1544 }
1545
1546 /* Clone the SID into the new SID table. */
1547 static int clone_sid(u32 sid,
1548 struct context *context,
1549 void *arg)
1550 {
1551 struct sidtab *s = arg;
1552
1553 if (sid > SECINITSID_NUM)
1554 return sidtab_insert(s, sid, context);
1555 else
1556 return 0;
1557 }
1558
1559 static inline int convert_context_handle_invalid_context(struct context *context)
1560 {
1561 int rc = 0;
1562
1563 if (selinux_enforcing) {
1564 rc = -EINVAL;
1565 } else {
1566 char *s;
1567 u32 len;
1568
1569 if (!context_struct_to_string(context, &s, &len)) {
1570 printk(KERN_WARNING
1571 "SELinux: Context %s would be invalid if enforcing\n",
1572 s);
1573 kfree(s);
1574 }
1575 }
1576 return rc;
1577 }
1578
1579 struct convert_context_args {
1580 struct policydb *oldp;
1581 struct policydb *newp;
1582 };
1583
1584 /*
1585 * Convert the values in the security context
1586 * structure `c' from the values specified
1587 * in the policy `p->oldp' to the values specified
1588 * in the policy `p->newp'. Verify that the
1589 * context is valid under the new policy.
1590 */
1591 static int convert_context(u32 key,
1592 struct context *c,
1593 void *p)
1594 {
1595 struct convert_context_args *args;
1596 struct context oldc;
1597 struct ocontext *oc;
1598 struct mls_range *range;
1599 struct role_datum *role;
1600 struct type_datum *typdatum;
1601 struct user_datum *usrdatum;
1602 char *s;
1603 u32 len;
1604 int rc = 0;
1605
1606 if (key <= SECINITSID_NUM)
1607 goto out;
1608
1609 args = p;
1610
1611 if (c->str) {
1612 struct context ctx;
1613 s = kstrdup(c->str, GFP_KERNEL);
1614 if (!s) {
1615 rc = -ENOMEM;
1616 goto out;
1617 }
1618 rc = string_to_context_struct(args->newp, NULL, s,
1619 c->len, &ctx, SECSID_NULL);
1620 kfree(s);
1621 if (!rc) {
1622 printk(KERN_INFO
1623 "SELinux: Context %s became valid (mapped).\n",
1624 c->str);
1625 /* Replace string with mapped representation. */
1626 kfree(c->str);
1627 memcpy(c, &ctx, sizeof(*c));
1628 goto out;
1629 } else if (rc == -EINVAL) {
1630 /* Retain string representation for later mapping. */
1631 rc = 0;
1632 goto out;
1633 } else {
1634 /* Other error condition, e.g. ENOMEM. */
1635 printk(KERN_ERR
1636 "SELinux: Unable to map context %s, rc = %d.\n",
1637 c->str, -rc);
1638 goto out;
1639 }
1640 }
1641
1642 rc = context_cpy(&oldc, c);
1643 if (rc)
1644 goto out;
1645
1646 rc = -EINVAL;
1647
1648 /* Convert the user. */
1649 usrdatum = hashtab_search(args->newp->p_users.table,
1650 args->oldp->p_user_val_to_name[c->user - 1]);
1651 if (!usrdatum)
1652 goto bad;
1653 c->user = usrdatum->value;
1654
1655 /* Convert the role. */
1656 role = hashtab_search(args->newp->p_roles.table,
1657 args->oldp->p_role_val_to_name[c->role - 1]);
1658 if (!role)
1659 goto bad;
1660 c->role = role->value;
1661
1662 /* Convert the type. */
1663 typdatum = hashtab_search(args->newp->p_types.table,
1664 args->oldp->p_type_val_to_name[c->type - 1]);
1665 if (!typdatum)
1666 goto bad;
1667 c->type = typdatum->value;
1668
1669 /* Convert the MLS fields if dealing with MLS policies */
1670 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1671 rc = mls_convert_context(args->oldp, args->newp, c);
1672 if (rc)
1673 goto bad;
1674 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1675 /*
1676 * Switching between MLS and non-MLS policy:
1677 * free any storage used by the MLS fields in the
1678 * context for all existing entries in the sidtab.
1679 */
1680 mls_context_destroy(c);
1681 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1682 /*
1683 * Switching between non-MLS and MLS policy:
1684 * ensure that the MLS fields of the context for all
1685 * existing entries in the sidtab are filled in with a
1686 * suitable default value, likely taken from one of the
1687 * initial SIDs.
1688 */
1689 oc = args->newp->ocontexts[OCON_ISID];
1690 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1691 oc = oc->next;
1692 if (!oc) {
1693 printk(KERN_ERR "SELinux: unable to look up"
1694 " the initial SIDs list\n");
1695 goto bad;
1696 }
1697 range = &oc->context[0].range;
1698 rc = mls_range_set(c, range);
1699 if (rc)
1700 goto bad;
1701 }
1702
1703 /* Check the validity of the new context. */
1704 if (!policydb_context_isvalid(args->newp, c)) {
1705 rc = convert_context_handle_invalid_context(&oldc);
1706 if (rc)
1707 goto bad;
1708 }
1709
1710 context_destroy(&oldc);
1711 rc = 0;
1712 out:
1713 return rc;
1714 bad:
1715 /* Map old representation to string and save it. */
1716 if (context_struct_to_string(&oldc, &s, &len))
1717 return -ENOMEM;
1718 context_destroy(&oldc);
1719 context_destroy(c);
1720 c->str = s;
1721 c->len = len;
1722 printk(KERN_INFO
1723 "SELinux: Context %s became invalid (unmapped).\n",
1724 c->str);
1725 rc = 0;
1726 goto out;
1727 }
1728
1729 static void security_load_policycaps(void)
1730 {
1731 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1732 POLICYDB_CAPABILITY_NETPEER);
1733 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1734 POLICYDB_CAPABILITY_OPENPERM);
1735 }
1736
1737 extern void selinux_complete_init(void);
1738 static int security_preserve_bools(struct policydb *p);
1739
1740 /**
1741 * security_load_policy - Load a security policy configuration.
1742 * @data: binary policy data
1743 * @len: length of data in bytes
1744 *
1745 * Load a new set of security policy configuration data,
1746 * validate it and convert the SID table as necessary.
1747 * This function will flush the access vector cache after
1748 * loading the new policy.
1749 */
1750 int security_load_policy(void *data, size_t len)
1751 {
1752 struct policydb oldpolicydb, newpolicydb;
1753 struct sidtab oldsidtab, newsidtab;
1754 struct selinux_mapping *oldmap, *map = NULL;
1755 struct convert_context_args args;
1756 u32 seqno;
1757 u16 map_size;
1758 int rc = 0;
1759 struct policy_file file = { data, len }, *fp = &file;
1760
1761 if (!ss_initialized) {
1762 avtab_cache_init();
1763 rc = policydb_read(&policydb, fp);
1764 if (rc) {
1765 avtab_cache_destroy();
1766 return rc;
1767 }
1768
1769 rc = selinux_set_mapping(&policydb, secclass_map,
1770 &current_mapping,
1771 &current_mapping_size);
1772 if (rc) {
1773 policydb_destroy(&policydb);
1774 avtab_cache_destroy();
1775 return rc;
1776 }
1777
1778 rc = policydb_load_isids(&policydb, &sidtab);
1779 if (rc) {
1780 policydb_destroy(&policydb);
1781 avtab_cache_destroy();
1782 return rc;
1783 }
1784
1785 security_load_policycaps();
1786 ss_initialized = 1;
1787 seqno = ++latest_granting;
1788 selinux_complete_init();
1789 avc_ss_reset(seqno);
1790 selnl_notify_policyload(seqno);
1791 selinux_netlbl_cache_invalidate();
1792 selinux_xfrm_notify_policyload();
1793 return 0;
1794 }
1795
1796 #if 0
1797 sidtab_hash_eval(&sidtab, "sids");
1798 #endif
1799
1800 rc = policydb_read(&newpolicydb, fp);
1801 if (rc)
1802 return rc;
1803
1804 /* If switching between different policy types, log MLS status */
1805 if (policydb.mls_enabled && !newpolicydb.mls_enabled)
1806 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
1807 else if (!policydb.mls_enabled && newpolicydb.mls_enabled)
1808 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
1809
1810 rc = policydb_load_isids(&newpolicydb, &newsidtab);
1811 if (rc) {
1812 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
1813 policydb_destroy(&newpolicydb);
1814 return rc;
1815 }
1816
1817 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size);
1818 if (rc)
1819 goto err;
1820
1821 rc = security_preserve_bools(&newpolicydb);
1822 if (rc) {
1823 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
1824 goto err;
1825 }
1826
1827 /* Clone the SID table. */
1828 sidtab_shutdown(&sidtab);
1829
1830 rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
1831 if (rc)
1832 goto err;
1833
1834 /*
1835 * Convert the internal representations of contexts
1836 * in the new SID table.
1837 */
1838 args.oldp = &policydb;
1839 args.newp = &newpolicydb;
1840 rc = sidtab_map(&newsidtab, convert_context, &args);
1841 if (rc) {
1842 printk(KERN_ERR "SELinux: unable to convert the internal"
1843 " representation of contexts in the new SID"
1844 " table\n");
1845 goto err;
1846 }
1847
1848 /* Save the old policydb and SID table to free later. */
1849 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1850 sidtab_set(&oldsidtab, &sidtab);
1851
1852 /* Install the new policydb and SID table. */
1853 write_lock_irq(&policy_rwlock);
1854 memcpy(&policydb, &newpolicydb, sizeof policydb);
1855 sidtab_set(&sidtab, &newsidtab);
1856 security_load_policycaps();
1857 oldmap = current_mapping;
1858 current_mapping = map;
1859 current_mapping_size = map_size;
1860 seqno = ++latest_granting;
1861 write_unlock_irq(&policy_rwlock);
1862
1863 /* Free the old policydb and SID table. */
1864 policydb_destroy(&oldpolicydb);
1865 sidtab_destroy(&oldsidtab);
1866 kfree(oldmap);
1867
1868 avc_ss_reset(seqno);
1869 selnl_notify_policyload(seqno);
1870 selinux_netlbl_cache_invalidate();
1871 selinux_xfrm_notify_policyload();
1872
1873 return 0;
1874
1875 err:
1876 kfree(map);
1877 sidtab_destroy(&newsidtab);
1878 policydb_destroy(&newpolicydb);
1879 return rc;
1880
1881 }
1882
1883 /**
1884 * security_port_sid - Obtain the SID for a port.
1885 * @protocol: protocol number
1886 * @port: port number
1887 * @out_sid: security identifier
1888 */
1889 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1890 {
1891 struct ocontext *c;
1892 int rc = 0;
1893
1894 read_lock(&policy_rwlock);
1895
1896 c = policydb.ocontexts[OCON_PORT];
1897 while (c) {
1898 if (c->u.port.protocol == protocol &&
1899 c->u.port.low_port <= port &&
1900 c->u.port.high_port >= port)
1901 break;
1902 c = c->next;
1903 }
1904
1905 if (c) {
1906 if (!c->sid[0]) {
1907 rc = sidtab_context_to_sid(&sidtab,
1908 &c->context[0],
1909 &c->sid[0]);
1910 if (rc)
1911 goto out;
1912 }
1913 *out_sid = c->sid[0];
1914 } else {
1915 *out_sid = SECINITSID_PORT;
1916 }
1917
1918 out:
1919 read_unlock(&policy_rwlock);
1920 return rc;
1921 }
1922
1923 /**
1924 * security_netif_sid - Obtain the SID for a network interface.
1925 * @name: interface name
1926 * @if_sid: interface SID
1927 */
1928 int security_netif_sid(char *name, u32 *if_sid)
1929 {
1930 int rc = 0;
1931 struct ocontext *c;
1932
1933 read_lock(&policy_rwlock);
1934
1935 c = policydb.ocontexts[OCON_NETIF];
1936 while (c) {
1937 if (strcmp(name, c->u.name) == 0)
1938 break;
1939 c = c->next;
1940 }
1941
1942 if (c) {
1943 if (!c->sid[0] || !c->sid[1]) {
1944 rc = sidtab_context_to_sid(&sidtab,
1945 &c->context[0],
1946 &c->sid[0]);
1947 if (rc)
1948 goto out;
1949 rc = sidtab_context_to_sid(&sidtab,
1950 &c->context[1],
1951 &c->sid[1]);
1952 if (rc)
1953 goto out;
1954 }
1955 *if_sid = c->sid[0];
1956 } else
1957 *if_sid = SECINITSID_NETIF;
1958
1959 out:
1960 read_unlock(&policy_rwlock);
1961 return rc;
1962 }
1963
1964 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1965 {
1966 int i, fail = 0;
1967
1968 for (i = 0; i < 4; i++)
1969 if (addr[i] != (input[i] & mask[i])) {
1970 fail = 1;
1971 break;
1972 }
1973
1974 return !fail;
1975 }
1976
1977 /**
1978 * security_node_sid - Obtain the SID for a node (host).
1979 * @domain: communication domain aka address family
1980 * @addrp: address
1981 * @addrlen: address length in bytes
1982 * @out_sid: security identifier
1983 */
1984 int security_node_sid(u16 domain,
1985 void *addrp,
1986 u32 addrlen,
1987 u32 *out_sid)
1988 {
1989 int rc = 0;
1990 struct ocontext *c;
1991
1992 read_lock(&policy_rwlock);
1993
1994 switch (domain) {
1995 case AF_INET: {
1996 u32 addr;
1997
1998 if (addrlen != sizeof(u32)) {
1999 rc = -EINVAL;
2000 goto out;
2001 }
2002
2003 addr = *((u32 *)addrp);
2004
2005 c = policydb.ocontexts[OCON_NODE];
2006 while (c) {
2007 if (c->u.node.addr == (addr & c->u.node.mask))
2008 break;
2009 c = c->next;
2010 }
2011 break;
2012 }
2013
2014 case AF_INET6:
2015 if (addrlen != sizeof(u64) * 2) {
2016 rc = -EINVAL;
2017 goto out;
2018 }
2019 c = policydb.ocontexts[OCON_NODE6];
2020 while (c) {
2021 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2022 c->u.node6.mask))
2023 break;
2024 c = c->next;
2025 }
2026 break;
2027
2028 default:
2029 *out_sid = SECINITSID_NODE;
2030 goto out;
2031 }
2032
2033 if (c) {
2034 if (!c->sid[0]) {
2035 rc = sidtab_context_to_sid(&sidtab,
2036 &c->context[0],
2037 &c->sid[0]);
2038 if (rc)
2039 goto out;
2040 }
2041 *out_sid = c->sid[0];
2042 } else {
2043 *out_sid = SECINITSID_NODE;
2044 }
2045
2046 out:
2047 read_unlock(&policy_rwlock);
2048 return rc;
2049 }
2050
2051 #define SIDS_NEL 25
2052
2053 /**
2054 * security_get_user_sids - Obtain reachable SIDs for a user.
2055 * @fromsid: starting SID
2056 * @username: username
2057 * @sids: array of reachable SIDs for user
2058 * @nel: number of elements in @sids
2059 *
2060 * Generate the set of SIDs for legal security contexts
2061 * for a given user that can be reached by @fromsid.
2062 * Set *@sids to point to a dynamically allocated
2063 * array containing the set of SIDs. Set *@nel to the
2064 * number of elements in the array.
2065 */
2066
2067 int security_get_user_sids(u32 fromsid,
2068 char *username,
2069 u32 **sids,
2070 u32 *nel)
2071 {
2072 struct context *fromcon, usercon;
2073 u32 *mysids = NULL, *mysids2, sid;
2074 u32 mynel = 0, maxnel = SIDS_NEL;
2075 struct user_datum *user;
2076 struct role_datum *role;
2077 struct ebitmap_node *rnode, *tnode;
2078 int rc = 0, i, j;
2079
2080 *sids = NULL;
2081 *nel = 0;
2082
2083 if (!ss_initialized)
2084 goto out;
2085
2086 read_lock(&policy_rwlock);
2087
2088 context_init(&usercon);
2089
2090 fromcon = sidtab_search(&sidtab, fromsid);
2091 if (!fromcon) {
2092 rc = -EINVAL;
2093 goto out_unlock;
2094 }
2095
2096 user = hashtab_search(policydb.p_users.table, username);
2097 if (!user) {
2098 rc = -EINVAL;
2099 goto out_unlock;
2100 }
2101 usercon.user = user->value;
2102
2103 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2104 if (!mysids) {
2105 rc = -ENOMEM;
2106 goto out_unlock;
2107 }
2108
2109 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2110 role = policydb.role_val_to_struct[i];
2111 usercon.role = i + 1;
2112 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2113 usercon.type = j + 1;
2114
2115 if (mls_setup_user_range(fromcon, user, &usercon))
2116 continue;
2117
2118 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2119 if (rc)
2120 goto out_unlock;
2121 if (mynel < maxnel) {
2122 mysids[mynel++] = sid;
2123 } else {
2124 maxnel += SIDS_NEL;
2125 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2126 if (!mysids2) {
2127 rc = -ENOMEM;
2128 goto out_unlock;
2129 }
2130 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2131 kfree(mysids);
2132 mysids = mysids2;
2133 mysids[mynel++] = sid;
2134 }
2135 }
2136 }
2137
2138 out_unlock:
2139 read_unlock(&policy_rwlock);
2140 if (rc || !mynel) {
2141 kfree(mysids);
2142 goto out;
2143 }
2144
2145 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2146 if (!mysids2) {
2147 rc = -ENOMEM;
2148 kfree(mysids);
2149 goto out;
2150 }
2151 for (i = 0, j = 0; i < mynel; i++) {
2152 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2153 SECCLASS_PROCESS, /* kernel value */
2154 PROCESS__TRANSITION, AVC_STRICT,
2155 NULL);
2156 if (!rc)
2157 mysids2[j++] = mysids[i];
2158 cond_resched();
2159 }
2160 rc = 0;
2161 kfree(mysids);
2162 *sids = mysids2;
2163 *nel = j;
2164 out:
2165 return rc;
2166 }
2167
2168 /**
2169 * security_genfs_sid - Obtain a SID for a file in a filesystem
2170 * @fstype: filesystem type
2171 * @path: path from root of mount
2172 * @sclass: file security class
2173 * @sid: SID for path
2174 *
2175 * Obtain a SID to use for a file in a filesystem that
2176 * cannot support xattr or use a fixed labeling behavior like
2177 * transition SIDs or task SIDs.
2178 */
2179 int security_genfs_sid(const char *fstype,
2180 char *path,
2181 u16 orig_sclass,
2182 u32 *sid)
2183 {
2184 int len;
2185 u16 sclass;
2186 struct genfs *genfs;
2187 struct ocontext *c;
2188 int rc = 0, cmp = 0;
2189
2190 while (path[0] == '/' && path[1] == '/')
2191 path++;
2192
2193 read_lock(&policy_rwlock);
2194
2195 sclass = unmap_class(orig_sclass);
2196
2197 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2198 cmp = strcmp(fstype, genfs->fstype);
2199 if (cmp <= 0)
2200 break;
2201 }
2202
2203 if (!genfs || cmp) {
2204 *sid = SECINITSID_UNLABELED;
2205 rc = -ENOENT;
2206 goto out;
2207 }
2208
2209 for (c = genfs->head; c; c = c->next) {
2210 len = strlen(c->u.name);
2211 if ((!c->v.sclass || sclass == c->v.sclass) &&
2212 (strncmp(c->u.name, path, len) == 0))
2213 break;
2214 }
2215
2216 if (!c) {
2217 *sid = SECINITSID_UNLABELED;
2218 rc = -ENOENT;
2219 goto out;
2220 }
2221
2222 if (!c->sid[0]) {
2223 rc = sidtab_context_to_sid(&sidtab,
2224 &c->context[0],
2225 &c->sid[0]);
2226 if (rc)
2227 goto out;
2228 }
2229
2230 *sid = c->sid[0];
2231 out:
2232 read_unlock(&policy_rwlock);
2233 return rc;
2234 }
2235
2236 /**
2237 * security_fs_use - Determine how to handle labeling for a filesystem.
2238 * @fstype: filesystem type
2239 * @behavior: labeling behavior
2240 * @sid: SID for filesystem (superblock)
2241 */
2242 int security_fs_use(
2243 const char *fstype,
2244 unsigned int *behavior,
2245 u32 *sid)
2246 {
2247 int rc = 0;
2248 struct ocontext *c;
2249
2250 read_lock(&policy_rwlock);
2251
2252 c = policydb.ocontexts[OCON_FSUSE];
2253 while (c) {
2254 if (strcmp(fstype, c->u.name) == 0)
2255 break;
2256 c = c->next;
2257 }
2258
2259 if (c) {
2260 *behavior = c->v.behavior;
2261 if (!c->sid[0]) {
2262 rc = sidtab_context_to_sid(&sidtab,
2263 &c->context[0],
2264 &c->sid[0]);
2265 if (rc)
2266 goto out;
2267 }
2268 *sid = c->sid[0];
2269 } else {
2270 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
2271 if (rc) {
2272 *behavior = SECURITY_FS_USE_NONE;
2273 rc = 0;
2274 } else {
2275 *behavior = SECURITY_FS_USE_GENFS;
2276 }
2277 }
2278
2279 out:
2280 read_unlock(&policy_rwlock);
2281 return rc;
2282 }
2283
2284 int security_get_bools(int *len, char ***names, int **values)
2285 {
2286 int i, rc = -ENOMEM;
2287
2288 read_lock(&policy_rwlock);
2289 *names = NULL;
2290 *values = NULL;
2291
2292 *len = policydb.p_bools.nprim;
2293 if (!*len) {
2294 rc = 0;
2295 goto out;
2296 }
2297
2298 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2299 if (!*names)
2300 goto err;
2301
2302 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2303 if (!*values)
2304 goto err;
2305
2306 for (i = 0; i < *len; i++) {
2307 size_t name_len;
2308 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2309 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
2310 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
2311 if (!(*names)[i])
2312 goto err;
2313 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
2314 (*names)[i][name_len - 1] = 0;
2315 }
2316 rc = 0;
2317 out:
2318 read_unlock(&policy_rwlock);
2319 return rc;
2320 err:
2321 if (*names) {
2322 for (i = 0; i < *len; i++)
2323 kfree((*names)[i]);
2324 }
2325 kfree(*values);
2326 goto out;
2327 }
2328
2329
2330 int security_set_bools(int len, int *values)
2331 {
2332 int i, rc = 0;
2333 int lenp, seqno = 0;
2334 struct cond_node *cur;
2335
2336 write_lock_irq(&policy_rwlock);
2337
2338 lenp = policydb.p_bools.nprim;
2339 if (len != lenp) {
2340 rc = -EFAULT;
2341 goto out;
2342 }
2343
2344 for (i = 0; i < len; i++) {
2345 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2346 audit_log(current->audit_context, GFP_ATOMIC,
2347 AUDIT_MAC_CONFIG_CHANGE,
2348 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2349 policydb.p_bool_val_to_name[i],
2350 !!values[i],
2351 policydb.bool_val_to_struct[i]->state,
2352 audit_get_loginuid(current),
2353 audit_get_sessionid(current));
2354 }
2355 if (values[i])
2356 policydb.bool_val_to_struct[i]->state = 1;
2357 else
2358 policydb.bool_val_to_struct[i]->state = 0;
2359 }
2360
2361 for (cur = policydb.cond_list; cur; cur = cur->next) {
2362 rc = evaluate_cond_node(&policydb, cur);
2363 if (rc)
2364 goto out;
2365 }
2366
2367 seqno = ++latest_granting;
2368
2369 out:
2370 write_unlock_irq(&policy_rwlock);
2371 if (!rc) {
2372 avc_ss_reset(seqno);
2373 selnl_notify_policyload(seqno);
2374 selinux_xfrm_notify_policyload();
2375 }
2376 return rc;
2377 }
2378
2379 int security_get_bool_value(int bool)
2380 {
2381 int rc = 0;
2382 int len;
2383
2384 read_lock(&policy_rwlock);
2385
2386 len = policydb.p_bools.nprim;
2387 if (bool >= len) {
2388 rc = -EFAULT;
2389 goto out;
2390 }
2391
2392 rc = policydb.bool_val_to_struct[bool]->state;
2393 out:
2394 read_unlock(&policy_rwlock);
2395 return rc;
2396 }
2397
2398 static int security_preserve_bools(struct policydb *p)
2399 {
2400 int rc, nbools = 0, *bvalues = NULL, i;
2401 char **bnames = NULL;
2402 struct cond_bool_datum *booldatum;
2403 struct cond_node *cur;
2404
2405 rc = security_get_bools(&nbools, &bnames, &bvalues);
2406 if (rc)
2407 goto out;
2408 for (i = 0; i < nbools; i++) {
2409 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2410 if (booldatum)
2411 booldatum->state = bvalues[i];
2412 }
2413 for (cur = p->cond_list; cur; cur = cur->next) {
2414 rc = evaluate_cond_node(p, cur);
2415 if (rc)
2416 goto out;
2417 }
2418
2419 out:
2420 if (bnames) {
2421 for (i = 0; i < nbools; i++)
2422 kfree(bnames[i]);
2423 }
2424 kfree(bnames);
2425 kfree(bvalues);
2426 return rc;
2427 }
2428
2429 /*
2430 * security_sid_mls_copy() - computes a new sid based on the given
2431 * sid and the mls portion of mls_sid.
2432 */
2433 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2434 {
2435 struct context *context1;
2436 struct context *context2;
2437 struct context newcon;
2438 char *s;
2439 u32 len;
2440 int rc = 0;
2441
2442 if (!ss_initialized || !policydb.mls_enabled) {
2443 *new_sid = sid;
2444 goto out;
2445 }
2446
2447 context_init(&newcon);
2448
2449 read_lock(&policy_rwlock);
2450 context1 = sidtab_search(&sidtab, sid);
2451 if (!context1) {
2452 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2453 __func__, sid);
2454 rc = -EINVAL;
2455 goto out_unlock;
2456 }
2457
2458 context2 = sidtab_search(&sidtab, mls_sid);
2459 if (!context2) {
2460 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2461 __func__, mls_sid);
2462 rc = -EINVAL;
2463 goto out_unlock;
2464 }
2465
2466 newcon.user = context1->user;
2467 newcon.role = context1->role;
2468 newcon.type = context1->type;
2469 rc = mls_context_cpy(&newcon, context2);
2470 if (rc)
2471 goto out_unlock;
2472
2473 /* Check the validity of the new context. */
2474 if (!policydb_context_isvalid(&policydb, &newcon)) {
2475 rc = convert_context_handle_invalid_context(&newcon);
2476 if (rc)
2477 goto bad;
2478 }
2479
2480 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2481 goto out_unlock;
2482
2483 bad:
2484 if (!context_struct_to_string(&newcon, &s, &len)) {
2485 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2486 "security_sid_mls_copy: invalid context %s", s);
2487 kfree(s);
2488 }
2489
2490 out_unlock:
2491 read_unlock(&policy_rwlock);
2492 context_destroy(&newcon);
2493 out:
2494 return rc;
2495 }
2496
2497 /**
2498 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2499 * @nlbl_sid: NetLabel SID
2500 * @nlbl_type: NetLabel labeling protocol type
2501 * @xfrm_sid: XFRM SID
2502 *
2503 * Description:
2504 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2505 * resolved into a single SID it is returned via @peer_sid and the function
2506 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
2507 * returns a negative value. A table summarizing the behavior is below:
2508 *
2509 * | function return | @sid
2510 * ------------------------------+-----------------+-----------------
2511 * no peer labels | 0 | SECSID_NULL
2512 * single peer label | 0 | <peer_label>
2513 * multiple, consistent labels | 0 | <peer_label>
2514 * multiple, inconsistent labels | -<errno> | SECSID_NULL
2515 *
2516 */
2517 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2518 u32 xfrm_sid,
2519 u32 *peer_sid)
2520 {
2521 int rc;
2522 struct context *nlbl_ctx;
2523 struct context *xfrm_ctx;
2524
2525 /* handle the common (which also happens to be the set of easy) cases
2526 * right away, these two if statements catch everything involving a
2527 * single or absent peer SID/label */
2528 if (xfrm_sid == SECSID_NULL) {
2529 *peer_sid = nlbl_sid;
2530 return 0;
2531 }
2532 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2533 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2534 * is present */
2535 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2536 *peer_sid = xfrm_sid;
2537 return 0;
2538 }
2539
2540 /* we don't need to check ss_initialized here since the only way both
2541 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2542 * security server was initialized and ss_initialized was true */
2543 if (!policydb.mls_enabled) {
2544 *peer_sid = SECSID_NULL;
2545 return 0;
2546 }
2547
2548 read_lock(&policy_rwlock);
2549
2550 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2551 if (!nlbl_ctx) {
2552 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2553 __func__, nlbl_sid);
2554 rc = -EINVAL;
2555 goto out_slowpath;
2556 }
2557 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2558 if (!xfrm_ctx) {
2559 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2560 __func__, xfrm_sid);
2561 rc = -EINVAL;
2562 goto out_slowpath;
2563 }
2564 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2565
2566 out_slowpath:
2567 read_unlock(&policy_rwlock);
2568 if (rc == 0)
2569 /* at present NetLabel SIDs/labels really only carry MLS
2570 * information so if the MLS portion of the NetLabel SID
2571 * matches the MLS portion of the labeled XFRM SID/label
2572 * then pass along the XFRM SID as it is the most
2573 * expressive */
2574 *peer_sid = xfrm_sid;
2575 else
2576 *peer_sid = SECSID_NULL;
2577 return rc;
2578 }
2579
2580 static int get_classes_callback(void *k, void *d, void *args)
2581 {
2582 struct class_datum *datum = d;
2583 char *name = k, **classes = args;
2584 int value = datum->value - 1;
2585
2586 classes[value] = kstrdup(name, GFP_ATOMIC);
2587 if (!classes[value])
2588 return -ENOMEM;
2589
2590 return 0;
2591 }
2592
2593 int security_get_classes(char ***classes, int *nclasses)
2594 {
2595 int rc = -ENOMEM;
2596
2597 read_lock(&policy_rwlock);
2598
2599 *nclasses = policydb.p_classes.nprim;
2600 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
2601 if (!*classes)
2602 goto out;
2603
2604 rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2605 *classes);
2606 if (rc < 0) {
2607 int i;
2608 for (i = 0; i < *nclasses; i++)
2609 kfree((*classes)[i]);
2610 kfree(*classes);
2611 }
2612
2613 out:
2614 read_unlock(&policy_rwlock);
2615 return rc;
2616 }
2617
2618 static int get_permissions_callback(void *k, void *d, void *args)
2619 {
2620 struct perm_datum *datum = d;
2621 char *name = k, **perms = args;
2622 int value = datum->value - 1;
2623
2624 perms[value] = kstrdup(name, GFP_ATOMIC);
2625 if (!perms[value])
2626 return -ENOMEM;
2627
2628 return 0;
2629 }
2630
2631 int security_get_permissions(char *class, char ***perms, int *nperms)
2632 {
2633 int rc = -ENOMEM, i;
2634 struct class_datum *match;
2635
2636 read_lock(&policy_rwlock);
2637
2638 match = hashtab_search(policydb.p_classes.table, class);
2639 if (!match) {
2640 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
2641 __func__, class);
2642 rc = -EINVAL;
2643 goto out;
2644 }
2645
2646 *nperms = match->permissions.nprim;
2647 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
2648 if (!*perms)
2649 goto out;
2650
2651 if (match->comdatum) {
2652 rc = hashtab_map(match->comdatum->permissions.table,
2653 get_permissions_callback, *perms);
2654 if (rc < 0)
2655 goto err;
2656 }
2657
2658 rc = hashtab_map(match->permissions.table, get_permissions_callback,
2659 *perms);
2660 if (rc < 0)
2661 goto err;
2662
2663 out:
2664 read_unlock(&policy_rwlock);
2665 return rc;
2666
2667 err:
2668 read_unlock(&policy_rwlock);
2669 for (i = 0; i < *nperms; i++)
2670 kfree((*perms)[i]);
2671 kfree(*perms);
2672 return rc;
2673 }
2674
2675 int security_get_reject_unknown(void)
2676 {
2677 return policydb.reject_unknown;
2678 }
2679
2680 int security_get_allow_unknown(void)
2681 {
2682 return policydb.allow_unknown;
2683 }
2684
2685 /**
2686 * security_policycap_supported - Check for a specific policy capability
2687 * @req_cap: capability
2688 *
2689 * Description:
2690 * This function queries the currently loaded policy to see if it supports the
2691 * capability specified by @req_cap. Returns true (1) if the capability is
2692 * supported, false (0) if it isn't supported.
2693 *
2694 */
2695 int security_policycap_supported(unsigned int req_cap)
2696 {
2697 int rc;
2698
2699 read_lock(&policy_rwlock);
2700 rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2701 read_unlock(&policy_rwlock);
2702
2703 return rc;
2704 }
2705
2706 struct selinux_audit_rule {
2707 u32 au_seqno;
2708 struct context au_ctxt;
2709 };
2710
2711 void selinux_audit_rule_free(void *vrule)
2712 {
2713 struct selinux_audit_rule *rule = vrule;
2714
2715 if (rule) {
2716 context_destroy(&rule->au_ctxt);
2717 kfree(rule);
2718 }
2719 }
2720
2721 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2722 {
2723 struct selinux_audit_rule *tmprule;
2724 struct role_datum *roledatum;
2725 struct type_datum *typedatum;
2726 struct user_datum *userdatum;
2727 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2728 int rc = 0;
2729
2730 *rule = NULL;
2731
2732 if (!ss_initialized)
2733 return -EOPNOTSUPP;
2734
2735 switch (field) {
2736 case AUDIT_SUBJ_USER:
2737 case AUDIT_SUBJ_ROLE:
2738 case AUDIT_SUBJ_TYPE:
2739 case AUDIT_OBJ_USER:
2740 case AUDIT_OBJ_ROLE:
2741 case AUDIT_OBJ_TYPE:
2742 /* only 'equals' and 'not equals' fit user, role, and type */
2743 if (op != Audit_equal && op != Audit_not_equal)
2744 return -EINVAL;
2745 break;
2746 case AUDIT_SUBJ_SEN:
2747 case AUDIT_SUBJ_CLR:
2748 case AUDIT_OBJ_LEV_LOW:
2749 case AUDIT_OBJ_LEV_HIGH:
2750 /* we do not allow a range, indicated by the presense of '-' */
2751 if (strchr(rulestr, '-'))
2752 return -EINVAL;
2753 break;
2754 default:
2755 /* only the above fields are valid */
2756 return -EINVAL;
2757 }
2758
2759 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2760 if (!tmprule)
2761 return -ENOMEM;
2762
2763 context_init(&tmprule->au_ctxt);
2764
2765 read_lock(&policy_rwlock);
2766
2767 tmprule->au_seqno = latest_granting;
2768
2769 switch (field) {
2770 case AUDIT_SUBJ_USER:
2771 case AUDIT_OBJ_USER:
2772 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2773 if (!userdatum)
2774 rc = -EINVAL;
2775 else
2776 tmprule->au_ctxt.user = userdatum->value;
2777 break;
2778 case AUDIT_SUBJ_ROLE:
2779 case AUDIT_OBJ_ROLE:
2780 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2781 if (!roledatum)
2782 rc = -EINVAL;
2783 else
2784 tmprule->au_ctxt.role = roledatum->value;
2785 break;
2786 case AUDIT_SUBJ_TYPE:
2787 case AUDIT_OBJ_TYPE:
2788 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2789 if (!typedatum)
2790 rc = -EINVAL;
2791 else
2792 tmprule->au_ctxt.type = typedatum->value;
2793 break;
2794 case AUDIT_SUBJ_SEN:
2795 case AUDIT_SUBJ_CLR:
2796 case AUDIT_OBJ_LEV_LOW:
2797 case AUDIT_OBJ_LEV_HIGH:
2798 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2799 break;
2800 }
2801
2802 read_unlock(&policy_rwlock);
2803
2804 if (rc) {
2805 selinux_audit_rule_free(tmprule);
2806 tmprule = NULL;
2807 }
2808
2809 *rule = tmprule;
2810
2811 return rc;
2812 }
2813
2814 /* Check to see if the rule contains any selinux fields */
2815 int selinux_audit_rule_known(struct audit_krule *rule)
2816 {
2817 int i;
2818
2819 for (i = 0; i < rule->field_count; i++) {
2820 struct audit_field *f = &rule->fields[i];
2821 switch (f->type) {
2822 case AUDIT_SUBJ_USER:
2823 case AUDIT_SUBJ_ROLE:
2824 case AUDIT_SUBJ_TYPE:
2825 case AUDIT_SUBJ_SEN:
2826 case AUDIT_SUBJ_CLR:
2827 case AUDIT_OBJ_USER:
2828 case AUDIT_OBJ_ROLE:
2829 case AUDIT_OBJ_TYPE:
2830 case AUDIT_OBJ_LEV_LOW:
2831 case AUDIT_OBJ_LEV_HIGH:
2832 return 1;
2833 }
2834 }
2835
2836 return 0;
2837 }
2838
2839 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2840 struct audit_context *actx)
2841 {
2842 struct context *ctxt;
2843 struct mls_level *level;
2844 struct selinux_audit_rule *rule = vrule;
2845 int match = 0;
2846
2847 if (!rule) {
2848 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2849 "selinux_audit_rule_match: missing rule\n");
2850 return -ENOENT;
2851 }
2852
2853 read_lock(&policy_rwlock);
2854
2855 if (rule->au_seqno < latest_granting) {
2856 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2857 "selinux_audit_rule_match: stale rule\n");
2858 match = -ESTALE;
2859 goto out;
2860 }
2861
2862 ctxt = sidtab_search(&sidtab, sid);
2863 if (!ctxt) {
2864 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2865 "selinux_audit_rule_match: unrecognized SID %d\n",
2866 sid);
2867 match = -ENOENT;
2868 goto out;
2869 }
2870
2871 /* a field/op pair that is not caught here will simply fall through
2872 without a match */
2873 switch (field) {
2874 case AUDIT_SUBJ_USER:
2875 case AUDIT_OBJ_USER:
2876 switch (op) {
2877 case Audit_equal:
2878 match = (ctxt->user == rule->au_ctxt.user);
2879 break;
2880 case Audit_not_equal:
2881 match = (ctxt->user != rule->au_ctxt.user);
2882 break;
2883 }
2884 break;
2885 case AUDIT_SUBJ_ROLE:
2886 case AUDIT_OBJ_ROLE:
2887 switch (op) {
2888 case Audit_equal:
2889 match = (ctxt->role == rule->au_ctxt.role);
2890 break;
2891 case Audit_not_equal:
2892 match = (ctxt->role != rule->au_ctxt.role);
2893 break;
2894 }
2895 break;
2896 case AUDIT_SUBJ_TYPE:
2897 case AUDIT_OBJ_TYPE:
2898 switch (op) {
2899 case Audit_equal:
2900 match = (ctxt->type == rule->au_ctxt.type);
2901 break;
2902 case Audit_not_equal:
2903 match = (ctxt->type != rule->au_ctxt.type);
2904 break;
2905 }
2906 break;
2907 case AUDIT_SUBJ_SEN:
2908 case AUDIT_SUBJ_CLR:
2909 case AUDIT_OBJ_LEV_LOW:
2910 case AUDIT_OBJ_LEV_HIGH:
2911 level = ((field == AUDIT_SUBJ_SEN ||
2912 field == AUDIT_OBJ_LEV_LOW) ?
2913 &ctxt->range.level[0] : &ctxt->range.level[1]);
2914 switch (op) {
2915 case Audit_equal:
2916 match = mls_level_eq(&rule->au_ctxt.range.level[0],
2917 level);
2918 break;
2919 case Audit_not_equal:
2920 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2921 level);
2922 break;
2923 case Audit_lt:
2924 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2925 level) &&
2926 !mls_level_eq(&rule->au_ctxt.range.level[0],
2927 level));
2928 break;
2929 case Audit_le:
2930 match = mls_level_dom(&rule->au_ctxt.range.level[0],
2931 level);
2932 break;
2933 case Audit_gt:
2934 match = (mls_level_dom(level,
2935 &rule->au_ctxt.range.level[0]) &&
2936 !mls_level_eq(level,
2937 &rule->au_ctxt.range.level[0]));
2938 break;
2939 case Audit_ge:
2940 match = mls_level_dom(level,
2941 &rule->au_ctxt.range.level[0]);
2942 break;
2943 }
2944 }
2945
2946 out:
2947 read_unlock(&policy_rwlock);
2948 return match;
2949 }
2950
2951 static int (*aurule_callback)(void) = audit_update_lsm_rules;
2952
2953 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
2954 u16 class, u32 perms, u32 *retained)
2955 {
2956 int err = 0;
2957
2958 if (event == AVC_CALLBACK_RESET && aurule_callback)
2959 err = aurule_callback();
2960 return err;
2961 }
2962
2963 static int __init aurule_init(void)
2964 {
2965 int err;
2966
2967 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
2968 SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
2969 if (err)
2970 panic("avc_add_callback() failed, error %d\n", err);
2971
2972 return err;
2973 }
2974 __initcall(aurule_init);
2975
2976 #ifdef CONFIG_NETLABEL
2977 /**
2978 * security_netlbl_cache_add - Add an entry to the NetLabel cache
2979 * @secattr: the NetLabel packet security attributes
2980 * @sid: the SELinux SID
2981 *
2982 * Description:
2983 * Attempt to cache the context in @ctx, which was derived from the packet in
2984 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
2985 * already been initialized.
2986 *
2987 */
2988 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
2989 u32 sid)
2990 {
2991 u32 *sid_cache;
2992
2993 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
2994 if (sid_cache == NULL)
2995 return;
2996 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
2997 if (secattr->cache == NULL) {
2998 kfree(sid_cache);
2999 return;
3000 }
3001
3002 *sid_cache = sid;
3003 secattr->cache->free = kfree;
3004 secattr->cache->data = sid_cache;
3005 secattr->flags |= NETLBL_SECATTR_CACHE;
3006 }
3007
3008 /**
3009 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3010 * @secattr: the NetLabel packet security attributes
3011 * @sid: the SELinux SID
3012 *
3013 * Description:
3014 * Convert the given NetLabel security attributes in @secattr into a
3015 * SELinux SID. If the @secattr field does not contain a full SELinux
3016 * SID/context then use SECINITSID_NETMSG as the foundation. If possibile the
3017 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3018 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3019 * conversion for future lookups. Returns zero on success, negative values on
3020 * failure.
3021 *
3022 */
3023 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3024 u32 *sid)
3025 {
3026 int rc = -EIDRM;
3027 struct context *ctx;
3028 struct context ctx_new;
3029
3030 if (!ss_initialized) {
3031 *sid = SECSID_NULL;
3032 return 0;
3033 }
3034
3035 read_lock(&policy_rwlock);
3036
3037 if (secattr->flags & NETLBL_SECATTR_CACHE) {
3038 *sid = *(u32 *)secattr->cache->data;
3039 rc = 0;
3040 } else if (secattr->flags & NETLBL_SECATTR_SECID) {
3041 *sid = secattr->attr.secid;
3042 rc = 0;
3043 } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3044 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3045 if (ctx == NULL)
3046 goto netlbl_secattr_to_sid_return;
3047
3048 context_init(&ctx_new);
3049 ctx_new.user = ctx->user;
3050 ctx_new.role = ctx->role;
3051 ctx_new.type = ctx->type;
3052 mls_import_netlbl_lvl(&ctx_new, secattr);
3053 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3054 if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
3055 secattr->attr.mls.cat) != 0)
3056 goto netlbl_secattr_to_sid_return;
3057 memcpy(&ctx_new.range.level[1].cat,
3058 &ctx_new.range.level[0].cat,
3059 sizeof(ctx_new.range.level[0].cat));
3060 }
3061 if (mls_context_isvalid(&policydb, &ctx_new) != 1)
3062 goto netlbl_secattr_to_sid_return_cleanup;
3063
3064 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3065 if (rc != 0)
3066 goto netlbl_secattr_to_sid_return_cleanup;
3067
3068 security_netlbl_cache_add(secattr, *sid);
3069
3070 ebitmap_destroy(&ctx_new.range.level[0].cat);
3071 } else {
3072 *sid = SECSID_NULL;
3073 rc = 0;
3074 }
3075
3076 netlbl_secattr_to_sid_return:
3077 read_unlock(&policy_rwlock);
3078 return rc;
3079 netlbl_secattr_to_sid_return_cleanup:
3080 ebitmap_destroy(&ctx_new.range.level[0].cat);
3081 goto netlbl_secattr_to_sid_return;
3082 }
3083
3084 /**
3085 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3086 * @sid: the SELinux SID
3087 * @secattr: the NetLabel packet security attributes
3088 *
3089 * Description:
3090 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3091 * Returns zero on success, negative values on failure.
3092 *
3093 */
3094 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3095 {
3096 int rc;
3097 struct context *ctx;
3098
3099 if (!ss_initialized)
3100 return 0;
3101
3102 read_lock(&policy_rwlock);
3103 ctx = sidtab_search(&sidtab, sid);
3104 if (ctx == NULL) {
3105 rc = -ENOENT;
3106 goto netlbl_sid_to_secattr_failure;
3107 }
3108 secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
3109 GFP_ATOMIC);
3110 if (secattr->domain == NULL) {
3111 rc = -ENOMEM;
3112 goto netlbl_sid_to_secattr_failure;
3113 }
3114 secattr->attr.secid = sid;
3115 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3116 mls_export_netlbl_lvl(ctx, secattr);
3117 rc = mls_export_netlbl_cat(ctx, secattr);
3118 if (rc != 0)
3119 goto netlbl_sid_to_secattr_failure;
3120 read_unlock(&policy_rwlock);
3121
3122 return 0;
3123
3124 netlbl_sid_to_secattr_failure:
3125 read_unlock(&policy_rwlock);
3126 return rc;
3127 }
3128 #endif /* CONFIG_NETLABEL */
linux-next