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Merge branch 'for-2638/i2c/nomadik' into for-linus/i2c-2638
[deliverable/linux.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.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 <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 extern void selnl_notify_policyload(u32 seqno);
74
75 int selinux_policycap_netpeer;
76 int selinux_policycap_openperm;
77
78 static DEFINE_RWLOCK(policy_rwlock);
79
80 static struct sidtab sidtab;
81 struct policydb policydb;
82 int ss_initialized;
83
84 /*
85 * The largest sequence number that has been used when
86 * providing an access decision to the access vector cache.
87 * The sequence number only changes when a policy change
88 * occurs.
89 */
90 static u32 latest_granting;
91
92 /* Forward declaration. */
93 static int context_struct_to_string(struct context *context, char **scontext,
94 u32 *scontext_len);
95
96 static void context_struct_compute_av(struct context *scontext,
97 struct context *tcontext,
98 u16 tclass,
99 struct av_decision *avd);
100
101 struct selinux_mapping {
102 u16 value; /* policy value */
103 unsigned num_perms;
104 u32 perms[sizeof(u32) * 8];
105 };
106
107 static struct selinux_mapping *current_mapping;
108 static u16 current_mapping_size;
109
110 static int selinux_set_mapping(struct policydb *pol,
111 struct security_class_mapping *map,
112 struct selinux_mapping **out_map_p,
113 u16 *out_map_size)
114 {
115 struct selinux_mapping *out_map = NULL;
116 size_t size = sizeof(struct selinux_mapping);
117 u16 i, j;
118 unsigned k;
119 bool print_unknown_handle = false;
120
121 /* Find number of classes in the input mapping */
122 if (!map)
123 return -EINVAL;
124 i = 0;
125 while (map[i].name)
126 i++;
127
128 /* Allocate space for the class records, plus one for class zero */
129 out_map = kcalloc(++i, size, GFP_ATOMIC);
130 if (!out_map)
131 return -ENOMEM;
132
133 /* Store the raw class and permission values */
134 j = 0;
135 while (map[j].name) {
136 struct security_class_mapping *p_in = map + (j++);
137 struct selinux_mapping *p_out = out_map + j;
138
139 /* An empty class string skips ahead */
140 if (!strcmp(p_in->name, "")) {
141 p_out->num_perms = 0;
142 continue;
143 }
144
145 p_out->value = string_to_security_class(pol, p_in->name);
146 if (!p_out->value) {
147 printk(KERN_INFO
148 "SELinux: Class %s not defined in policy.\n",
149 p_in->name);
150 if (pol->reject_unknown)
151 goto err;
152 p_out->num_perms = 0;
153 print_unknown_handle = true;
154 continue;
155 }
156
157 k = 0;
158 while (p_in->perms && p_in->perms[k]) {
159 /* An empty permission string skips ahead */
160 if (!*p_in->perms[k]) {
161 k++;
162 continue;
163 }
164 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
165 p_in->perms[k]);
166 if (!p_out->perms[k]) {
167 printk(KERN_INFO
168 "SELinux: Permission %s in class %s not defined in policy.\n",
169 p_in->perms[k], p_in->name);
170 if (pol->reject_unknown)
171 goto err;
172 print_unknown_handle = true;
173 }
174
175 k++;
176 }
177 p_out->num_perms = k;
178 }
179
180 if (print_unknown_handle)
181 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
182 pol->allow_unknown ? "allowed" : "denied");
183
184 *out_map_p = out_map;
185 *out_map_size = i;
186 return 0;
187 err:
188 kfree(out_map);
189 return -EINVAL;
190 }
191
192 /*
193 * Get real, policy values from mapped values
194 */
195
196 static u16 unmap_class(u16 tclass)
197 {
198 if (tclass < current_mapping_size)
199 return current_mapping[tclass].value;
200
201 return tclass;
202 }
203
204 static void map_decision(u16 tclass, struct av_decision *avd,
205 int allow_unknown)
206 {
207 if (tclass < current_mapping_size) {
208 unsigned i, n = current_mapping[tclass].num_perms;
209 u32 result;
210
211 for (i = 0, result = 0; i < n; i++) {
212 if (avd->allowed & current_mapping[tclass].perms[i])
213 result |= 1<<i;
214 if (allow_unknown && !current_mapping[tclass].perms[i])
215 result |= 1<<i;
216 }
217 avd->allowed = result;
218
219 for (i = 0, result = 0; i < n; i++)
220 if (avd->auditallow & current_mapping[tclass].perms[i])
221 result |= 1<<i;
222 avd->auditallow = result;
223
224 for (i = 0, result = 0; i < n; i++) {
225 if (avd->auditdeny & current_mapping[tclass].perms[i])
226 result |= 1<<i;
227 if (!allow_unknown && !current_mapping[tclass].perms[i])
228 result |= 1<<i;
229 }
230 /*
231 * In case the kernel has a bug and requests a permission
232 * between num_perms and the maximum permission number, we
233 * should audit that denial
234 */
235 for (; i < (sizeof(u32)*8); i++)
236 result |= 1<<i;
237 avd->auditdeny = result;
238 }
239 }
240
241 int security_mls_enabled(void)
242 {
243 return policydb.mls_enabled;
244 }
245
246 /*
247 * Return the boolean value of a constraint expression
248 * when it is applied to the specified source and target
249 * security contexts.
250 *
251 * xcontext is a special beast... It is used by the validatetrans rules
252 * only. For these rules, scontext is the context before the transition,
253 * tcontext is the context after the transition, and xcontext is the context
254 * of the process performing the transition. All other callers of
255 * constraint_expr_eval should pass in NULL for xcontext.
256 */
257 static int constraint_expr_eval(struct context *scontext,
258 struct context *tcontext,
259 struct context *xcontext,
260 struct constraint_expr *cexpr)
261 {
262 u32 val1, val2;
263 struct context *c;
264 struct role_datum *r1, *r2;
265 struct mls_level *l1, *l2;
266 struct constraint_expr *e;
267 int s[CEXPR_MAXDEPTH];
268 int sp = -1;
269
270 for (e = cexpr; e; e = e->next) {
271 switch (e->expr_type) {
272 case CEXPR_NOT:
273 BUG_ON(sp < 0);
274 s[sp] = !s[sp];
275 break;
276 case CEXPR_AND:
277 BUG_ON(sp < 1);
278 sp--;
279 s[sp] &= s[sp + 1];
280 break;
281 case CEXPR_OR:
282 BUG_ON(sp < 1);
283 sp--;
284 s[sp] |= s[sp + 1];
285 break;
286 case CEXPR_ATTR:
287 if (sp == (CEXPR_MAXDEPTH - 1))
288 return 0;
289 switch (e->attr) {
290 case CEXPR_USER:
291 val1 = scontext->user;
292 val2 = tcontext->user;
293 break;
294 case CEXPR_TYPE:
295 val1 = scontext->type;
296 val2 = tcontext->type;
297 break;
298 case CEXPR_ROLE:
299 val1 = scontext->role;
300 val2 = tcontext->role;
301 r1 = policydb.role_val_to_struct[val1 - 1];
302 r2 = policydb.role_val_to_struct[val2 - 1];
303 switch (e->op) {
304 case CEXPR_DOM:
305 s[++sp] = ebitmap_get_bit(&r1->dominates,
306 val2 - 1);
307 continue;
308 case CEXPR_DOMBY:
309 s[++sp] = ebitmap_get_bit(&r2->dominates,
310 val1 - 1);
311 continue;
312 case CEXPR_INCOMP:
313 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
314 val2 - 1) &&
315 !ebitmap_get_bit(&r2->dominates,
316 val1 - 1));
317 continue;
318 default:
319 break;
320 }
321 break;
322 case CEXPR_L1L2:
323 l1 = &(scontext->range.level[0]);
324 l2 = &(tcontext->range.level[0]);
325 goto mls_ops;
326 case CEXPR_L1H2:
327 l1 = &(scontext->range.level[0]);
328 l2 = &(tcontext->range.level[1]);
329 goto mls_ops;
330 case CEXPR_H1L2:
331 l1 = &(scontext->range.level[1]);
332 l2 = &(tcontext->range.level[0]);
333 goto mls_ops;
334 case CEXPR_H1H2:
335 l1 = &(scontext->range.level[1]);
336 l2 = &(tcontext->range.level[1]);
337 goto mls_ops;
338 case CEXPR_L1H1:
339 l1 = &(scontext->range.level[0]);
340 l2 = &(scontext->range.level[1]);
341 goto mls_ops;
342 case CEXPR_L2H2:
343 l1 = &(tcontext->range.level[0]);
344 l2 = &(tcontext->range.level[1]);
345 goto mls_ops;
346 mls_ops:
347 switch (e->op) {
348 case CEXPR_EQ:
349 s[++sp] = mls_level_eq(l1, l2);
350 continue;
351 case CEXPR_NEQ:
352 s[++sp] = !mls_level_eq(l1, l2);
353 continue;
354 case CEXPR_DOM:
355 s[++sp] = mls_level_dom(l1, l2);
356 continue;
357 case CEXPR_DOMBY:
358 s[++sp] = mls_level_dom(l2, l1);
359 continue;
360 case CEXPR_INCOMP:
361 s[++sp] = mls_level_incomp(l2, l1);
362 continue;
363 default:
364 BUG();
365 return 0;
366 }
367 break;
368 default:
369 BUG();
370 return 0;
371 }
372
373 switch (e->op) {
374 case CEXPR_EQ:
375 s[++sp] = (val1 == val2);
376 break;
377 case CEXPR_NEQ:
378 s[++sp] = (val1 != val2);
379 break;
380 default:
381 BUG();
382 return 0;
383 }
384 break;
385 case CEXPR_NAMES:
386 if (sp == (CEXPR_MAXDEPTH-1))
387 return 0;
388 c = scontext;
389 if (e->attr & CEXPR_TARGET)
390 c = tcontext;
391 else if (e->attr & CEXPR_XTARGET) {
392 c = xcontext;
393 if (!c) {
394 BUG();
395 return 0;
396 }
397 }
398 if (e->attr & CEXPR_USER)
399 val1 = c->user;
400 else if (e->attr & CEXPR_ROLE)
401 val1 = c->role;
402 else if (e->attr & CEXPR_TYPE)
403 val1 = c->type;
404 else {
405 BUG();
406 return 0;
407 }
408
409 switch (e->op) {
410 case CEXPR_EQ:
411 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
412 break;
413 case CEXPR_NEQ:
414 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
415 break;
416 default:
417 BUG();
418 return 0;
419 }
420 break;
421 default:
422 BUG();
423 return 0;
424 }
425 }
426
427 BUG_ON(sp != 0);
428 return s[0];
429 }
430
431 /*
432 * security_dump_masked_av - dumps masked permissions during
433 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
434 */
435 static int dump_masked_av_helper(void *k, void *d, void *args)
436 {
437 struct perm_datum *pdatum = d;
438 char **permission_names = args;
439
440 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
441
442 permission_names[pdatum->value - 1] = (char *)k;
443
444 return 0;
445 }
446
447 static void security_dump_masked_av(struct context *scontext,
448 struct context *tcontext,
449 u16 tclass,
450 u32 permissions,
451 const char *reason)
452 {
453 struct common_datum *common_dat;
454 struct class_datum *tclass_dat;
455 struct audit_buffer *ab;
456 char *tclass_name;
457 char *scontext_name = NULL;
458 char *tcontext_name = NULL;
459 char *permission_names[32];
460 int index;
461 u32 length;
462 bool need_comma = false;
463
464 if (!permissions)
465 return;
466
467 tclass_name = sym_name(&policydb, SYM_CLASSES, tclass - 1);
468 tclass_dat = policydb.class_val_to_struct[tclass - 1];
469 common_dat = tclass_dat->comdatum;
470
471 /* init permission_names */
472 if (common_dat &&
473 hashtab_map(common_dat->permissions.table,
474 dump_masked_av_helper, permission_names) < 0)
475 goto out;
476
477 if (hashtab_map(tclass_dat->permissions.table,
478 dump_masked_av_helper, permission_names) < 0)
479 goto out;
480
481 /* get scontext/tcontext in text form */
482 if (context_struct_to_string(scontext,
483 &scontext_name, &length) < 0)
484 goto out;
485
486 if (context_struct_to_string(tcontext,
487 &tcontext_name, &length) < 0)
488 goto out;
489
490 /* audit a message */
491 ab = audit_log_start(current->audit_context,
492 GFP_ATOMIC, AUDIT_SELINUX_ERR);
493 if (!ab)
494 goto out;
495
496 audit_log_format(ab, "op=security_compute_av reason=%s "
497 "scontext=%s tcontext=%s tclass=%s perms=",
498 reason, scontext_name, tcontext_name, tclass_name);
499
500 for (index = 0; index < 32; index++) {
501 u32 mask = (1 << index);
502
503 if ((mask & permissions) == 0)
504 continue;
505
506 audit_log_format(ab, "%s%s",
507 need_comma ? "," : "",
508 permission_names[index]
509 ? permission_names[index] : "????");
510 need_comma = true;
511 }
512 audit_log_end(ab);
513 out:
514 /* release scontext/tcontext */
515 kfree(tcontext_name);
516 kfree(scontext_name);
517
518 return;
519 }
520
521 /*
522 * security_boundary_permission - drops violated permissions
523 * on boundary constraint.
524 */
525 static void type_attribute_bounds_av(struct context *scontext,
526 struct context *tcontext,
527 u16 tclass,
528 struct av_decision *avd)
529 {
530 struct context lo_scontext;
531 struct context lo_tcontext;
532 struct av_decision lo_avd;
533 struct type_datum *source;
534 struct type_datum *target;
535 u32 masked = 0;
536
537 source = flex_array_get_ptr(policydb.type_val_to_struct_array,
538 scontext->type - 1);
539 BUG_ON(!source);
540
541 target = flex_array_get_ptr(policydb.type_val_to_struct_array,
542 tcontext->type - 1);
543 BUG_ON(!target);
544
545 if (source->bounds) {
546 memset(&lo_avd, 0, sizeof(lo_avd));
547
548 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
549 lo_scontext.type = source->bounds;
550
551 context_struct_compute_av(&lo_scontext,
552 tcontext,
553 tclass,
554 &lo_avd);
555 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
556 return; /* no masked permission */
557 masked = ~lo_avd.allowed & avd->allowed;
558 }
559
560 if (target->bounds) {
561 memset(&lo_avd, 0, sizeof(lo_avd));
562
563 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
564 lo_tcontext.type = target->bounds;
565
566 context_struct_compute_av(scontext,
567 &lo_tcontext,
568 tclass,
569 &lo_avd);
570 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
571 return; /* no masked permission */
572 masked = ~lo_avd.allowed & avd->allowed;
573 }
574
575 if (source->bounds && target->bounds) {
576 memset(&lo_avd, 0, sizeof(lo_avd));
577 /*
578 * lo_scontext and lo_tcontext are already
579 * set up.
580 */
581
582 context_struct_compute_av(&lo_scontext,
583 &lo_tcontext,
584 tclass,
585 &lo_avd);
586 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
587 return; /* no masked permission */
588 masked = ~lo_avd.allowed & avd->allowed;
589 }
590
591 if (masked) {
592 /* mask violated permissions */
593 avd->allowed &= ~masked;
594
595 /* audit masked permissions */
596 security_dump_masked_av(scontext, tcontext,
597 tclass, masked, "bounds");
598 }
599 }
600
601 /*
602 * Compute access vectors based on a context structure pair for
603 * the permissions in a particular class.
604 */
605 static void context_struct_compute_av(struct context *scontext,
606 struct context *tcontext,
607 u16 tclass,
608 struct av_decision *avd)
609 {
610 struct constraint_node *constraint;
611 struct role_allow *ra;
612 struct avtab_key avkey;
613 struct avtab_node *node;
614 struct class_datum *tclass_datum;
615 struct ebitmap *sattr, *tattr;
616 struct ebitmap_node *snode, *tnode;
617 unsigned int i, j;
618
619 avd->allowed = 0;
620 avd->auditallow = 0;
621 avd->auditdeny = 0xffffffff;
622
623 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
624 if (printk_ratelimit())
625 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass);
626 return;
627 }
628
629 tclass_datum = policydb.class_val_to_struct[tclass - 1];
630
631 /*
632 * If a specific type enforcement rule was defined for
633 * this permission check, then use it.
634 */
635 avkey.target_class = tclass;
636 avkey.specified = AVTAB_AV;
637 sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1);
638 BUG_ON(!sattr);
639 tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1);
640 BUG_ON(!tattr);
641 ebitmap_for_each_positive_bit(sattr, snode, i) {
642 ebitmap_for_each_positive_bit(tattr, tnode, j) {
643 avkey.source_type = i + 1;
644 avkey.target_type = j + 1;
645 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
646 node;
647 node = avtab_search_node_next(node, avkey.specified)) {
648 if (node->key.specified == AVTAB_ALLOWED)
649 avd->allowed |= node->datum.data;
650 else if (node->key.specified == AVTAB_AUDITALLOW)
651 avd->auditallow |= node->datum.data;
652 else if (node->key.specified == AVTAB_AUDITDENY)
653 avd->auditdeny &= node->datum.data;
654 }
655
656 /* Check conditional av table for additional permissions */
657 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
658
659 }
660 }
661
662 /*
663 * Remove any permissions prohibited by a constraint (this includes
664 * the MLS policy).
665 */
666 constraint = tclass_datum->constraints;
667 while (constraint) {
668 if ((constraint->permissions & (avd->allowed)) &&
669 !constraint_expr_eval(scontext, tcontext, NULL,
670 constraint->expr)) {
671 avd->allowed &= ~(constraint->permissions);
672 }
673 constraint = constraint->next;
674 }
675
676 /*
677 * If checking process transition permission and the
678 * role is changing, then check the (current_role, new_role)
679 * pair.
680 */
681 if (tclass == policydb.process_class &&
682 (avd->allowed & policydb.process_trans_perms) &&
683 scontext->role != tcontext->role) {
684 for (ra = policydb.role_allow; ra; ra = ra->next) {
685 if (scontext->role == ra->role &&
686 tcontext->role == ra->new_role)
687 break;
688 }
689 if (!ra)
690 avd->allowed &= ~policydb.process_trans_perms;
691 }
692
693 /*
694 * If the given source and target types have boundary
695 * constraint, lazy checks have to mask any violated
696 * permission and notice it to userspace via audit.
697 */
698 type_attribute_bounds_av(scontext, tcontext,
699 tclass, avd);
700 }
701
702 static int security_validtrans_handle_fail(struct context *ocontext,
703 struct context *ncontext,
704 struct context *tcontext,
705 u16 tclass)
706 {
707 char *o = NULL, *n = NULL, *t = NULL;
708 u32 olen, nlen, tlen;
709
710 if (context_struct_to_string(ocontext, &o, &olen))
711 goto out;
712 if (context_struct_to_string(ncontext, &n, &nlen))
713 goto out;
714 if (context_struct_to_string(tcontext, &t, &tlen))
715 goto out;
716 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
717 "security_validate_transition: denied for"
718 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
719 o, n, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
720 out:
721 kfree(o);
722 kfree(n);
723 kfree(t);
724
725 if (!selinux_enforcing)
726 return 0;
727 return -EPERM;
728 }
729
730 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
731 u16 orig_tclass)
732 {
733 struct context *ocontext;
734 struct context *ncontext;
735 struct context *tcontext;
736 struct class_datum *tclass_datum;
737 struct constraint_node *constraint;
738 u16 tclass;
739 int rc = 0;
740
741 if (!ss_initialized)
742 return 0;
743
744 read_lock(&policy_rwlock);
745
746 tclass = unmap_class(orig_tclass);
747
748 if (!tclass || tclass > policydb.p_classes.nprim) {
749 printk(KERN_ERR "SELinux: %s: unrecognized class %d\n",
750 __func__, tclass);
751 rc = -EINVAL;
752 goto out;
753 }
754 tclass_datum = policydb.class_val_to_struct[tclass - 1];
755
756 ocontext = sidtab_search(&sidtab, oldsid);
757 if (!ocontext) {
758 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
759 __func__, oldsid);
760 rc = -EINVAL;
761 goto out;
762 }
763
764 ncontext = sidtab_search(&sidtab, newsid);
765 if (!ncontext) {
766 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
767 __func__, newsid);
768 rc = -EINVAL;
769 goto out;
770 }
771
772 tcontext = sidtab_search(&sidtab, tasksid);
773 if (!tcontext) {
774 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
775 __func__, tasksid);
776 rc = -EINVAL;
777 goto out;
778 }
779
780 constraint = tclass_datum->validatetrans;
781 while (constraint) {
782 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
783 constraint->expr)) {
784 rc = security_validtrans_handle_fail(ocontext, ncontext,
785 tcontext, tclass);
786 goto out;
787 }
788 constraint = constraint->next;
789 }
790
791 out:
792 read_unlock(&policy_rwlock);
793 return rc;
794 }
795
796 /*
797 * security_bounded_transition - check whether the given
798 * transition is directed to bounded, or not.
799 * It returns 0, if @newsid is bounded by @oldsid.
800 * Otherwise, it returns error code.
801 *
802 * @oldsid : current security identifier
803 * @newsid : destinated security identifier
804 */
805 int security_bounded_transition(u32 old_sid, u32 new_sid)
806 {
807 struct context *old_context, *new_context;
808 struct type_datum *type;
809 int index;
810 int rc;
811
812 read_lock(&policy_rwlock);
813
814 rc = -EINVAL;
815 old_context = sidtab_search(&sidtab, old_sid);
816 if (!old_context) {
817 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
818 __func__, old_sid);
819 goto out;
820 }
821
822 rc = -EINVAL;
823 new_context = sidtab_search(&sidtab, new_sid);
824 if (!new_context) {
825 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
826 __func__, new_sid);
827 goto out;
828 }
829
830 rc = 0;
831 /* type/domain unchanged */
832 if (old_context->type == new_context->type)
833 goto out;
834
835 index = new_context->type;
836 while (true) {
837 type = flex_array_get_ptr(policydb.type_val_to_struct_array,
838 index - 1);
839 BUG_ON(!type);
840
841 /* not bounded anymore */
842 rc = -EPERM;
843 if (!type->bounds)
844 break;
845
846 /* @newsid is bounded by @oldsid */
847 rc = 0;
848 if (type->bounds == old_context->type)
849 break;
850
851 index = type->bounds;
852 }
853
854 if (rc) {
855 char *old_name = NULL;
856 char *new_name = NULL;
857 u32 length;
858
859 if (!context_struct_to_string(old_context,
860 &old_name, &length) &&
861 !context_struct_to_string(new_context,
862 &new_name, &length)) {
863 audit_log(current->audit_context,
864 GFP_ATOMIC, AUDIT_SELINUX_ERR,
865 "op=security_bounded_transition "
866 "result=denied "
867 "oldcontext=%s newcontext=%s",
868 old_name, new_name);
869 }
870 kfree(new_name);
871 kfree(old_name);
872 }
873 out:
874 read_unlock(&policy_rwlock);
875
876 return rc;
877 }
878
879 static void avd_init(struct av_decision *avd)
880 {
881 avd->allowed = 0;
882 avd->auditallow = 0;
883 avd->auditdeny = 0xffffffff;
884 avd->seqno = latest_granting;
885 avd->flags = 0;
886 }
887
888
889 /**
890 * security_compute_av - Compute access vector decisions.
891 * @ssid: source security identifier
892 * @tsid: target security identifier
893 * @tclass: target security class
894 * @avd: access vector decisions
895 *
896 * Compute a set of access vector decisions based on the
897 * SID pair (@ssid, @tsid) for the permissions in @tclass.
898 */
899 void security_compute_av(u32 ssid,
900 u32 tsid,
901 u16 orig_tclass,
902 struct av_decision *avd)
903 {
904 u16 tclass;
905 struct context *scontext = NULL, *tcontext = NULL;
906
907 read_lock(&policy_rwlock);
908 avd_init(avd);
909 if (!ss_initialized)
910 goto allow;
911
912 scontext = sidtab_search(&sidtab, ssid);
913 if (!scontext) {
914 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
915 __func__, ssid);
916 goto out;
917 }
918
919 /* permissive domain? */
920 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
921 avd->flags |= AVD_FLAGS_PERMISSIVE;
922
923 tcontext = sidtab_search(&sidtab, tsid);
924 if (!tcontext) {
925 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
926 __func__, tsid);
927 goto out;
928 }
929
930 tclass = unmap_class(orig_tclass);
931 if (unlikely(orig_tclass && !tclass)) {
932 if (policydb.allow_unknown)
933 goto allow;
934 goto out;
935 }
936 context_struct_compute_av(scontext, tcontext, tclass, avd);
937 map_decision(orig_tclass, avd, policydb.allow_unknown);
938 out:
939 read_unlock(&policy_rwlock);
940 return;
941 allow:
942 avd->allowed = 0xffffffff;
943 goto out;
944 }
945
946 void security_compute_av_user(u32 ssid,
947 u32 tsid,
948 u16 tclass,
949 struct av_decision *avd)
950 {
951 struct context *scontext = NULL, *tcontext = NULL;
952
953 read_lock(&policy_rwlock);
954 avd_init(avd);
955 if (!ss_initialized)
956 goto allow;
957
958 scontext = sidtab_search(&sidtab, ssid);
959 if (!scontext) {
960 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
961 __func__, ssid);
962 goto out;
963 }
964
965 /* permissive domain? */
966 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
967 avd->flags |= AVD_FLAGS_PERMISSIVE;
968
969 tcontext = sidtab_search(&sidtab, tsid);
970 if (!tcontext) {
971 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
972 __func__, tsid);
973 goto out;
974 }
975
976 if (unlikely(!tclass)) {
977 if (policydb.allow_unknown)
978 goto allow;
979 goto out;
980 }
981
982 context_struct_compute_av(scontext, tcontext, tclass, avd);
983 out:
984 read_unlock(&policy_rwlock);
985 return;
986 allow:
987 avd->allowed = 0xffffffff;
988 goto out;
989 }
990
991 /*
992 * Write the security context string representation of
993 * the context structure `context' into a dynamically
994 * allocated string of the correct size. Set `*scontext'
995 * to point to this string and set `*scontext_len' to
996 * the length of the string.
997 */
998 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
999 {
1000 char *scontextp;
1001
1002 if (scontext)
1003 *scontext = NULL;
1004 *scontext_len = 0;
1005
1006 if (context->len) {
1007 *scontext_len = context->len;
1008 *scontext = kstrdup(context->str, GFP_ATOMIC);
1009 if (!(*scontext))
1010 return -ENOMEM;
1011 return 0;
1012 }
1013
1014 /* Compute the size of the context. */
1015 *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1;
1016 *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1;
1017 *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1;
1018 *scontext_len += mls_compute_context_len(context);
1019
1020 if (!scontext)
1021 return 0;
1022
1023 /* Allocate space for the context; caller must free this space. */
1024 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1025 if (!scontextp)
1026 return -ENOMEM;
1027 *scontext = scontextp;
1028
1029 /*
1030 * Copy the user name, role name and type name into the context.
1031 */
1032 sprintf(scontextp, "%s:%s:%s",
1033 sym_name(&policydb, SYM_USERS, context->user - 1),
1034 sym_name(&policydb, SYM_ROLES, context->role - 1),
1035 sym_name(&policydb, SYM_TYPES, context->type - 1));
1036 scontextp += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) +
1037 1 + strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) +
1038 1 + strlen(sym_name(&policydb, SYM_TYPES, context->type - 1));
1039
1040 mls_sid_to_context(context, &scontextp);
1041
1042 *scontextp = 0;
1043
1044 return 0;
1045 }
1046
1047 #include "initial_sid_to_string.h"
1048
1049 const char *security_get_initial_sid_context(u32 sid)
1050 {
1051 if (unlikely(sid > SECINITSID_NUM))
1052 return NULL;
1053 return initial_sid_to_string[sid];
1054 }
1055
1056 static int security_sid_to_context_core(u32 sid, char **scontext,
1057 u32 *scontext_len, int force)
1058 {
1059 struct context *context;
1060 int rc = 0;
1061
1062 if (scontext)
1063 *scontext = NULL;
1064 *scontext_len = 0;
1065
1066 if (!ss_initialized) {
1067 if (sid <= SECINITSID_NUM) {
1068 char *scontextp;
1069
1070 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1071 if (!scontext)
1072 goto out;
1073 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1074 if (!scontextp) {
1075 rc = -ENOMEM;
1076 goto out;
1077 }
1078 strcpy(scontextp, initial_sid_to_string[sid]);
1079 *scontext = scontextp;
1080 goto out;
1081 }
1082 printk(KERN_ERR "SELinux: %s: called before initial "
1083 "load_policy on unknown SID %d\n", __func__, sid);
1084 rc = -EINVAL;
1085 goto out;
1086 }
1087 read_lock(&policy_rwlock);
1088 if (force)
1089 context = sidtab_search_force(&sidtab, sid);
1090 else
1091 context = sidtab_search(&sidtab, sid);
1092 if (!context) {
1093 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1094 __func__, sid);
1095 rc = -EINVAL;
1096 goto out_unlock;
1097 }
1098 rc = context_struct_to_string(context, scontext, scontext_len);
1099 out_unlock:
1100 read_unlock(&policy_rwlock);
1101 out:
1102 return rc;
1103
1104 }
1105
1106 /**
1107 * security_sid_to_context - Obtain a context for a given SID.
1108 * @sid: security identifier, SID
1109 * @scontext: security context
1110 * @scontext_len: length in bytes
1111 *
1112 * Write the string representation of the context associated with @sid
1113 * into a dynamically allocated string of the correct size. Set @scontext
1114 * to point to this string and set @scontext_len to the length of the string.
1115 */
1116 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1117 {
1118 return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1119 }
1120
1121 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1122 {
1123 return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1124 }
1125
1126 /*
1127 * Caveat: Mutates scontext.
1128 */
1129 static int string_to_context_struct(struct policydb *pol,
1130 struct sidtab *sidtabp,
1131 char *scontext,
1132 u32 scontext_len,
1133 struct context *ctx,
1134 u32 def_sid)
1135 {
1136 struct role_datum *role;
1137 struct type_datum *typdatum;
1138 struct user_datum *usrdatum;
1139 char *scontextp, *p, oldc;
1140 int rc = 0;
1141
1142 context_init(ctx);
1143
1144 /* Parse the security context. */
1145
1146 rc = -EINVAL;
1147 scontextp = (char *) scontext;
1148
1149 /* Extract the user. */
1150 p = scontextp;
1151 while (*p && *p != ':')
1152 p++;
1153
1154 if (*p == 0)
1155 goto out;
1156
1157 *p++ = 0;
1158
1159 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1160 if (!usrdatum)
1161 goto out;
1162
1163 ctx->user = usrdatum->value;
1164
1165 /* Extract role. */
1166 scontextp = p;
1167 while (*p && *p != ':')
1168 p++;
1169
1170 if (*p == 0)
1171 goto out;
1172
1173 *p++ = 0;
1174
1175 role = hashtab_search(pol->p_roles.table, scontextp);
1176 if (!role)
1177 goto out;
1178 ctx->role = role->value;
1179
1180 /* Extract type. */
1181 scontextp = p;
1182 while (*p && *p != ':')
1183 p++;
1184 oldc = *p;
1185 *p++ = 0;
1186
1187 typdatum = hashtab_search(pol->p_types.table, scontextp);
1188 if (!typdatum || typdatum->attribute)
1189 goto out;
1190
1191 ctx->type = typdatum->value;
1192
1193 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1194 if (rc)
1195 goto out;
1196
1197 rc = -EINVAL;
1198 if ((p - scontext) < scontext_len)
1199 goto out;
1200
1201 /* Check the validity of the new context. */
1202 if (!policydb_context_isvalid(pol, ctx))
1203 goto out;
1204 rc = 0;
1205 out:
1206 if (rc)
1207 context_destroy(ctx);
1208 return rc;
1209 }
1210
1211 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1212 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1213 int force)
1214 {
1215 char *scontext2, *str = NULL;
1216 struct context context;
1217 int rc = 0;
1218
1219 if (!ss_initialized) {
1220 int i;
1221
1222 for (i = 1; i < SECINITSID_NUM; i++) {
1223 if (!strcmp(initial_sid_to_string[i], scontext)) {
1224 *sid = i;
1225 return 0;
1226 }
1227 }
1228 *sid = SECINITSID_KERNEL;
1229 return 0;
1230 }
1231 *sid = SECSID_NULL;
1232
1233 /* Copy the string so that we can modify the copy as we parse it. */
1234 scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1235 if (!scontext2)
1236 return -ENOMEM;
1237 memcpy(scontext2, scontext, scontext_len);
1238 scontext2[scontext_len] = 0;
1239
1240 if (force) {
1241 /* Save another copy for storing in uninterpreted form */
1242 rc = -ENOMEM;
1243 str = kstrdup(scontext2, gfp_flags);
1244 if (!str)
1245 goto out;
1246 }
1247
1248 read_lock(&policy_rwlock);
1249 rc = string_to_context_struct(&policydb, &sidtab, scontext2,
1250 scontext_len, &context, def_sid);
1251 if (rc == -EINVAL && force) {
1252 context.str = str;
1253 context.len = scontext_len;
1254 str = NULL;
1255 } else if (rc)
1256 goto out_unlock;
1257 rc = sidtab_context_to_sid(&sidtab, &context, sid);
1258 context_destroy(&context);
1259 out_unlock:
1260 read_unlock(&policy_rwlock);
1261 out:
1262 kfree(scontext2);
1263 kfree(str);
1264 return rc;
1265 }
1266
1267 /**
1268 * security_context_to_sid - Obtain a SID for a given security context.
1269 * @scontext: security context
1270 * @scontext_len: length in bytes
1271 * @sid: security identifier, SID
1272 *
1273 * Obtains a SID associated with the security context that
1274 * has the string representation specified by @scontext.
1275 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1276 * memory is available, or 0 on success.
1277 */
1278 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
1279 {
1280 return security_context_to_sid_core(scontext, scontext_len,
1281 sid, SECSID_NULL, GFP_KERNEL, 0);
1282 }
1283
1284 /**
1285 * security_context_to_sid_default - Obtain a SID for a given security context,
1286 * falling back to specified default if needed.
1287 *
1288 * @scontext: security context
1289 * @scontext_len: length in bytes
1290 * @sid: security identifier, SID
1291 * @def_sid: default SID to assign on error
1292 *
1293 * Obtains a SID associated with the security context that
1294 * has the string representation specified by @scontext.
1295 * The default SID is passed to the MLS layer to be used to allow
1296 * kernel labeling of the MLS field if the MLS field is not present
1297 * (for upgrading to MLS without full relabel).
1298 * Implicitly forces adding of the context even if it cannot be mapped yet.
1299 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1300 * memory is available, or 0 on success.
1301 */
1302 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1303 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1304 {
1305 return security_context_to_sid_core(scontext, scontext_len,
1306 sid, def_sid, gfp_flags, 1);
1307 }
1308
1309 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1310 u32 *sid)
1311 {
1312 return security_context_to_sid_core(scontext, scontext_len,
1313 sid, SECSID_NULL, GFP_KERNEL, 1);
1314 }
1315
1316 static int compute_sid_handle_invalid_context(
1317 struct context *scontext,
1318 struct context *tcontext,
1319 u16 tclass,
1320 struct context *newcontext)
1321 {
1322 char *s = NULL, *t = NULL, *n = NULL;
1323 u32 slen, tlen, nlen;
1324
1325 if (context_struct_to_string(scontext, &s, &slen))
1326 goto out;
1327 if (context_struct_to_string(tcontext, &t, &tlen))
1328 goto out;
1329 if (context_struct_to_string(newcontext, &n, &nlen))
1330 goto out;
1331 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1332 "security_compute_sid: invalid context %s"
1333 " for scontext=%s"
1334 " tcontext=%s"
1335 " tclass=%s",
1336 n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
1337 out:
1338 kfree(s);
1339 kfree(t);
1340 kfree(n);
1341 if (!selinux_enforcing)
1342 return 0;
1343 return -EACCES;
1344 }
1345
1346 static int security_compute_sid(u32 ssid,
1347 u32 tsid,
1348 u16 orig_tclass,
1349 u32 specified,
1350 u32 *out_sid,
1351 bool kern)
1352 {
1353 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1354 struct role_trans *roletr = NULL;
1355 struct avtab_key avkey;
1356 struct avtab_datum *avdatum;
1357 struct avtab_node *node;
1358 u16 tclass;
1359 int rc = 0;
1360
1361 if (!ss_initialized) {
1362 switch (orig_tclass) {
1363 case SECCLASS_PROCESS: /* kernel value */
1364 *out_sid = ssid;
1365 break;
1366 default:
1367 *out_sid = tsid;
1368 break;
1369 }
1370 goto out;
1371 }
1372
1373 context_init(&newcontext);
1374
1375 read_lock(&policy_rwlock);
1376
1377 if (kern)
1378 tclass = unmap_class(orig_tclass);
1379 else
1380 tclass = orig_tclass;
1381
1382 scontext = sidtab_search(&sidtab, ssid);
1383 if (!scontext) {
1384 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1385 __func__, ssid);
1386 rc = -EINVAL;
1387 goto out_unlock;
1388 }
1389 tcontext = sidtab_search(&sidtab, tsid);
1390 if (!tcontext) {
1391 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1392 __func__, tsid);
1393 rc = -EINVAL;
1394 goto out_unlock;
1395 }
1396
1397 /* Set the user identity. */
1398 switch (specified) {
1399 case AVTAB_TRANSITION:
1400 case AVTAB_CHANGE:
1401 /* Use the process user identity. */
1402 newcontext.user = scontext->user;
1403 break;
1404 case AVTAB_MEMBER:
1405 /* Use the related object owner. */
1406 newcontext.user = tcontext->user;
1407 break;
1408 }
1409
1410 /* Set the role and type to default values. */
1411 if (tclass == policydb.process_class) {
1412 /* Use the current role and type of process. */
1413 newcontext.role = scontext->role;
1414 newcontext.type = scontext->type;
1415 } else {
1416 /* Use the well-defined object role. */
1417 newcontext.role = OBJECT_R_VAL;
1418 /* Use the type of the related object. */
1419 newcontext.type = tcontext->type;
1420 }
1421
1422 /* Look for a type transition/member/change rule. */
1423 avkey.source_type = scontext->type;
1424 avkey.target_type = tcontext->type;
1425 avkey.target_class = tclass;
1426 avkey.specified = specified;
1427 avdatum = avtab_search(&policydb.te_avtab, &avkey);
1428
1429 /* If no permanent rule, also check for enabled conditional rules */
1430 if (!avdatum) {
1431 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1432 for (; node; node = avtab_search_node_next(node, specified)) {
1433 if (node->key.specified & AVTAB_ENABLED) {
1434 avdatum = &node->datum;
1435 break;
1436 }
1437 }
1438 }
1439
1440 if (avdatum) {
1441 /* Use the type from the type transition/member/change rule. */
1442 newcontext.type = avdatum->data;
1443 }
1444
1445 /* Check for class-specific changes. */
1446 if (tclass == policydb.process_class) {
1447 if (specified & AVTAB_TRANSITION) {
1448 /* Look for a role transition rule. */
1449 for (roletr = policydb.role_tr; roletr;
1450 roletr = roletr->next) {
1451 if (roletr->role == scontext->role &&
1452 roletr->type == tcontext->type) {
1453 /* Use the role transition rule. */
1454 newcontext.role = roletr->new_role;
1455 break;
1456 }
1457 }
1458 }
1459 }
1460
1461 /* Set the MLS attributes.
1462 This is done last because it may allocate memory. */
1463 rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
1464 if (rc)
1465 goto out_unlock;
1466
1467 /* Check the validity of the context. */
1468 if (!policydb_context_isvalid(&policydb, &newcontext)) {
1469 rc = compute_sid_handle_invalid_context(scontext,
1470 tcontext,
1471 tclass,
1472 &newcontext);
1473 if (rc)
1474 goto out_unlock;
1475 }
1476 /* Obtain the sid for the context. */
1477 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1478 out_unlock:
1479 read_unlock(&policy_rwlock);
1480 context_destroy(&newcontext);
1481 out:
1482 return rc;
1483 }
1484
1485 /**
1486 * security_transition_sid - Compute the SID for a new subject/object.
1487 * @ssid: source security identifier
1488 * @tsid: target security identifier
1489 * @tclass: target security class
1490 * @out_sid: security identifier for new subject/object
1491 *
1492 * Compute a SID to use for labeling a new subject or object in the
1493 * class @tclass based on a SID pair (@ssid, @tsid).
1494 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1495 * if insufficient memory is available, or %0 if the new SID was
1496 * computed successfully.
1497 */
1498 int security_transition_sid(u32 ssid,
1499 u32 tsid,
1500 u16 tclass,
1501 u32 *out_sid)
1502 {
1503 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1504 out_sid, true);
1505 }
1506
1507 int security_transition_sid_user(u32 ssid,
1508 u32 tsid,
1509 u16 tclass,
1510 u32 *out_sid)
1511 {
1512 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1513 out_sid, false);
1514 }
1515
1516 /**
1517 * security_member_sid - Compute the SID for member selection.
1518 * @ssid: source security identifier
1519 * @tsid: target security identifier
1520 * @tclass: target security class
1521 * @out_sid: security identifier for selected member
1522 *
1523 * Compute a SID to use when selecting a member of a polyinstantiated
1524 * object of class @tclass based on a SID pair (@ssid, @tsid).
1525 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1526 * if insufficient memory is available, or %0 if the SID was
1527 * computed successfully.
1528 */
1529 int security_member_sid(u32 ssid,
1530 u32 tsid,
1531 u16 tclass,
1532 u32 *out_sid)
1533 {
1534 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid,
1535 false);
1536 }
1537
1538 /**
1539 * security_change_sid - Compute the SID for object relabeling.
1540 * @ssid: source security identifier
1541 * @tsid: target security identifier
1542 * @tclass: target security class
1543 * @out_sid: security identifier for selected member
1544 *
1545 * Compute a SID to use for relabeling an object of class @tclass
1546 * based on a SID pair (@ssid, @tsid).
1547 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1548 * if insufficient memory is available, or %0 if the SID was
1549 * computed successfully.
1550 */
1551 int security_change_sid(u32 ssid,
1552 u32 tsid,
1553 u16 tclass,
1554 u32 *out_sid)
1555 {
1556 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid,
1557 false);
1558 }
1559
1560 /* Clone the SID into the new SID table. */
1561 static int clone_sid(u32 sid,
1562 struct context *context,
1563 void *arg)
1564 {
1565 struct sidtab *s = arg;
1566
1567 if (sid > SECINITSID_NUM)
1568 return sidtab_insert(s, sid, context);
1569 else
1570 return 0;
1571 }
1572
1573 static inline int convert_context_handle_invalid_context(struct context *context)
1574 {
1575 char *s;
1576 u32 len;
1577
1578 if (selinux_enforcing)
1579 return -EINVAL;
1580
1581 if (!context_struct_to_string(context, &s, &len)) {
1582 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s);
1583 kfree(s);
1584 }
1585 return 0;
1586 }
1587
1588 struct convert_context_args {
1589 struct policydb *oldp;
1590 struct policydb *newp;
1591 };
1592
1593 /*
1594 * Convert the values in the security context
1595 * structure `c' from the values specified
1596 * in the policy `p->oldp' to the values specified
1597 * in the policy `p->newp'. Verify that the
1598 * context is valid under the new policy.
1599 */
1600 static int convert_context(u32 key,
1601 struct context *c,
1602 void *p)
1603 {
1604 struct convert_context_args *args;
1605 struct context oldc;
1606 struct ocontext *oc;
1607 struct mls_range *range;
1608 struct role_datum *role;
1609 struct type_datum *typdatum;
1610 struct user_datum *usrdatum;
1611 char *s;
1612 u32 len;
1613 int rc = 0;
1614
1615 if (key <= SECINITSID_NUM)
1616 goto out;
1617
1618 args = p;
1619
1620 if (c->str) {
1621 struct context ctx;
1622
1623 rc = -ENOMEM;
1624 s = kstrdup(c->str, GFP_KERNEL);
1625 if (!s)
1626 goto out;
1627
1628 rc = string_to_context_struct(args->newp, NULL, s,
1629 c->len, &ctx, SECSID_NULL);
1630 kfree(s);
1631 if (!rc) {
1632 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n",
1633 c->str);
1634 /* Replace string with mapped representation. */
1635 kfree(c->str);
1636 memcpy(c, &ctx, sizeof(*c));
1637 goto out;
1638 } else if (rc == -EINVAL) {
1639 /* Retain string representation for later mapping. */
1640 rc = 0;
1641 goto out;
1642 } else {
1643 /* Other error condition, e.g. ENOMEM. */
1644 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n",
1645 c->str, -rc);
1646 goto out;
1647 }
1648 }
1649
1650 rc = context_cpy(&oldc, c);
1651 if (rc)
1652 goto out;
1653
1654 /* Convert the user. */
1655 rc = -EINVAL;
1656 usrdatum = hashtab_search(args->newp->p_users.table,
1657 sym_name(args->oldp, SYM_USERS, c->user - 1));
1658 if (!usrdatum)
1659 goto bad;
1660 c->user = usrdatum->value;
1661
1662 /* Convert the role. */
1663 rc = -EINVAL;
1664 role = hashtab_search(args->newp->p_roles.table,
1665 sym_name(args->oldp, SYM_ROLES, c->role - 1));
1666 if (!role)
1667 goto bad;
1668 c->role = role->value;
1669
1670 /* Convert the type. */
1671 rc = -EINVAL;
1672 typdatum = hashtab_search(args->newp->p_types.table,
1673 sym_name(args->oldp, SYM_TYPES, c->type - 1));
1674 if (!typdatum)
1675 goto bad;
1676 c->type = typdatum->value;
1677
1678 /* Convert the MLS fields if dealing with MLS policies */
1679 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1680 rc = mls_convert_context(args->oldp, args->newp, c);
1681 if (rc)
1682 goto bad;
1683 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1684 /*
1685 * Switching between MLS and non-MLS policy:
1686 * free any storage used by the MLS fields in the
1687 * context for all existing entries in the sidtab.
1688 */
1689 mls_context_destroy(c);
1690 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1691 /*
1692 * Switching between non-MLS and MLS policy:
1693 * ensure that the MLS fields of the context for all
1694 * existing entries in the sidtab are filled in with a
1695 * suitable default value, likely taken from one of the
1696 * initial SIDs.
1697 */
1698 oc = args->newp->ocontexts[OCON_ISID];
1699 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1700 oc = oc->next;
1701 rc = -EINVAL;
1702 if (!oc) {
1703 printk(KERN_ERR "SELinux: unable to look up"
1704 " the initial SIDs list\n");
1705 goto bad;
1706 }
1707 range = &oc->context[0].range;
1708 rc = mls_range_set(c, range);
1709 if (rc)
1710 goto bad;
1711 }
1712
1713 /* Check the validity of the new context. */
1714 if (!policydb_context_isvalid(args->newp, c)) {
1715 rc = convert_context_handle_invalid_context(&oldc);
1716 if (rc)
1717 goto bad;
1718 }
1719
1720 context_destroy(&oldc);
1721
1722 rc = 0;
1723 out:
1724 return rc;
1725 bad:
1726 /* Map old representation to string and save it. */
1727 rc = context_struct_to_string(&oldc, &s, &len);
1728 if (rc)
1729 return rc;
1730 context_destroy(&oldc);
1731 context_destroy(c);
1732 c->str = s;
1733 c->len = len;
1734 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n",
1735 c->str);
1736 rc = 0;
1737 goto out;
1738 }
1739
1740 static void security_load_policycaps(void)
1741 {
1742 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1743 POLICYDB_CAPABILITY_NETPEER);
1744 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1745 POLICYDB_CAPABILITY_OPENPERM);
1746 }
1747
1748 extern void selinux_complete_init(void);
1749 static int security_preserve_bools(struct policydb *p);
1750
1751 /**
1752 * security_load_policy - Load a security policy configuration.
1753 * @data: binary policy data
1754 * @len: length of data in bytes
1755 *
1756 * Load a new set of security policy configuration data,
1757 * validate it and convert the SID table as necessary.
1758 * This function will flush the access vector cache after
1759 * loading the new policy.
1760 */
1761 int security_load_policy(void *data, size_t len)
1762 {
1763 struct policydb oldpolicydb, newpolicydb;
1764 struct sidtab oldsidtab, newsidtab;
1765 struct selinux_mapping *oldmap, *map = NULL;
1766 struct convert_context_args args;
1767 u32 seqno;
1768 u16 map_size;
1769 int rc = 0;
1770 struct policy_file file = { data, len }, *fp = &file;
1771
1772 if (!ss_initialized) {
1773 avtab_cache_init();
1774 rc = policydb_read(&policydb, fp);
1775 if (rc) {
1776 avtab_cache_destroy();
1777 return rc;
1778 }
1779
1780 policydb.len = len;
1781 rc = selinux_set_mapping(&policydb, secclass_map,
1782 &current_mapping,
1783 &current_mapping_size);
1784 if (rc) {
1785 policydb_destroy(&policydb);
1786 avtab_cache_destroy();
1787 return rc;
1788 }
1789
1790 rc = policydb_load_isids(&policydb, &sidtab);
1791 if (rc) {
1792 policydb_destroy(&policydb);
1793 avtab_cache_destroy();
1794 return rc;
1795 }
1796
1797 security_load_policycaps();
1798 ss_initialized = 1;
1799 seqno = ++latest_granting;
1800 selinux_complete_init();
1801 avc_ss_reset(seqno);
1802 selnl_notify_policyload(seqno);
1803 selinux_status_update_policyload(seqno);
1804 selinux_netlbl_cache_invalidate();
1805 selinux_xfrm_notify_policyload();
1806 return 0;
1807 }
1808
1809 #if 0
1810 sidtab_hash_eval(&sidtab, "sids");
1811 #endif
1812
1813 rc = policydb_read(&newpolicydb, fp);
1814 if (rc)
1815 return rc;
1816
1817 newpolicydb.len = len;
1818 /* If switching between different policy types, log MLS status */
1819 if (policydb.mls_enabled && !newpolicydb.mls_enabled)
1820 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
1821 else if (!policydb.mls_enabled && newpolicydb.mls_enabled)
1822 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
1823
1824 rc = policydb_load_isids(&newpolicydb, &newsidtab);
1825 if (rc) {
1826 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
1827 policydb_destroy(&newpolicydb);
1828 return rc;
1829 }
1830
1831 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size);
1832 if (rc)
1833 goto err;
1834
1835 rc = security_preserve_bools(&newpolicydb);
1836 if (rc) {
1837 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
1838 goto err;
1839 }
1840
1841 /* Clone the SID table. */
1842 sidtab_shutdown(&sidtab);
1843
1844 rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
1845 if (rc)
1846 goto err;
1847
1848 /*
1849 * Convert the internal representations of contexts
1850 * in the new SID table.
1851 */
1852 args.oldp = &policydb;
1853 args.newp = &newpolicydb;
1854 rc = sidtab_map(&newsidtab, convert_context, &args);
1855 if (rc) {
1856 printk(KERN_ERR "SELinux: unable to convert the internal"
1857 " representation of contexts in the new SID"
1858 " table\n");
1859 goto err;
1860 }
1861
1862 /* Save the old policydb and SID table to free later. */
1863 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1864 sidtab_set(&oldsidtab, &sidtab);
1865
1866 /* Install the new policydb and SID table. */
1867 write_lock_irq(&policy_rwlock);
1868 memcpy(&policydb, &newpolicydb, sizeof policydb);
1869 sidtab_set(&sidtab, &newsidtab);
1870 security_load_policycaps();
1871 oldmap = current_mapping;
1872 current_mapping = map;
1873 current_mapping_size = map_size;
1874 seqno = ++latest_granting;
1875 write_unlock_irq(&policy_rwlock);
1876
1877 /* Free the old policydb and SID table. */
1878 policydb_destroy(&oldpolicydb);
1879 sidtab_destroy(&oldsidtab);
1880 kfree(oldmap);
1881
1882 avc_ss_reset(seqno);
1883 selnl_notify_policyload(seqno);
1884 selinux_status_update_policyload(seqno);
1885 selinux_netlbl_cache_invalidate();
1886 selinux_xfrm_notify_policyload();
1887
1888 return 0;
1889
1890 err:
1891 kfree(map);
1892 sidtab_destroy(&newsidtab);
1893 policydb_destroy(&newpolicydb);
1894 return rc;
1895
1896 }
1897
1898 size_t security_policydb_len(void)
1899 {
1900 size_t len;
1901
1902 read_lock(&policy_rwlock);
1903 len = policydb.len;
1904 read_unlock(&policy_rwlock);
1905
1906 return len;
1907 }
1908
1909 /**
1910 * security_port_sid - Obtain the SID for a port.
1911 * @protocol: protocol number
1912 * @port: port number
1913 * @out_sid: security identifier
1914 */
1915 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1916 {
1917 struct ocontext *c;
1918 int rc = 0;
1919
1920 read_lock(&policy_rwlock);
1921
1922 c = policydb.ocontexts[OCON_PORT];
1923 while (c) {
1924 if (c->u.port.protocol == protocol &&
1925 c->u.port.low_port <= port &&
1926 c->u.port.high_port >= port)
1927 break;
1928 c = c->next;
1929 }
1930
1931 if (c) {
1932 if (!c->sid[0]) {
1933 rc = sidtab_context_to_sid(&sidtab,
1934 &c->context[0],
1935 &c->sid[0]);
1936 if (rc)
1937 goto out;
1938 }
1939 *out_sid = c->sid[0];
1940 } else {
1941 *out_sid = SECINITSID_PORT;
1942 }
1943
1944 out:
1945 read_unlock(&policy_rwlock);
1946 return rc;
1947 }
1948
1949 /**
1950 * security_netif_sid - Obtain the SID for a network interface.
1951 * @name: interface name
1952 * @if_sid: interface SID
1953 */
1954 int security_netif_sid(char *name, u32 *if_sid)
1955 {
1956 int rc = 0;
1957 struct ocontext *c;
1958
1959 read_lock(&policy_rwlock);
1960
1961 c = policydb.ocontexts[OCON_NETIF];
1962 while (c) {
1963 if (strcmp(name, c->u.name) == 0)
1964 break;
1965 c = c->next;
1966 }
1967
1968 if (c) {
1969 if (!c->sid[0] || !c->sid[1]) {
1970 rc = sidtab_context_to_sid(&sidtab,
1971 &c->context[0],
1972 &c->sid[0]);
1973 if (rc)
1974 goto out;
1975 rc = sidtab_context_to_sid(&sidtab,
1976 &c->context[1],
1977 &c->sid[1]);
1978 if (rc)
1979 goto out;
1980 }
1981 *if_sid = c->sid[0];
1982 } else
1983 *if_sid = SECINITSID_NETIF;
1984
1985 out:
1986 read_unlock(&policy_rwlock);
1987 return rc;
1988 }
1989
1990 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1991 {
1992 int i, fail = 0;
1993
1994 for (i = 0; i < 4; i++)
1995 if (addr[i] != (input[i] & mask[i])) {
1996 fail = 1;
1997 break;
1998 }
1999
2000 return !fail;
2001 }
2002
2003 /**
2004 * security_node_sid - Obtain the SID for a node (host).
2005 * @domain: communication domain aka address family
2006 * @addrp: address
2007 * @addrlen: address length in bytes
2008 * @out_sid: security identifier
2009 */
2010 int security_node_sid(u16 domain,
2011 void *addrp,
2012 u32 addrlen,
2013 u32 *out_sid)
2014 {
2015 int rc;
2016 struct ocontext *c;
2017
2018 read_lock(&policy_rwlock);
2019
2020 switch (domain) {
2021 case AF_INET: {
2022 u32 addr;
2023
2024 rc = -EINVAL;
2025 if (addrlen != sizeof(u32))
2026 goto out;
2027
2028 addr = *((u32 *)addrp);
2029
2030 c = policydb.ocontexts[OCON_NODE];
2031 while (c) {
2032 if (c->u.node.addr == (addr & c->u.node.mask))
2033 break;
2034 c = c->next;
2035 }
2036 break;
2037 }
2038
2039 case AF_INET6:
2040 rc = -EINVAL;
2041 if (addrlen != sizeof(u64) * 2)
2042 goto out;
2043 c = policydb.ocontexts[OCON_NODE6];
2044 while (c) {
2045 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2046 c->u.node6.mask))
2047 break;
2048 c = c->next;
2049 }
2050 break;
2051
2052 default:
2053 rc = 0;
2054 *out_sid = SECINITSID_NODE;
2055 goto out;
2056 }
2057
2058 if (c) {
2059 if (!c->sid[0]) {
2060 rc = sidtab_context_to_sid(&sidtab,
2061 &c->context[0],
2062 &c->sid[0]);
2063 if (rc)
2064 goto out;
2065 }
2066 *out_sid = c->sid[0];
2067 } else {
2068 *out_sid = SECINITSID_NODE;
2069 }
2070
2071 rc = 0;
2072 out:
2073 read_unlock(&policy_rwlock);
2074 return rc;
2075 }
2076
2077 #define SIDS_NEL 25
2078
2079 /**
2080 * security_get_user_sids - Obtain reachable SIDs for a user.
2081 * @fromsid: starting SID
2082 * @username: username
2083 * @sids: array of reachable SIDs for user
2084 * @nel: number of elements in @sids
2085 *
2086 * Generate the set of SIDs for legal security contexts
2087 * for a given user that can be reached by @fromsid.
2088 * Set *@sids to point to a dynamically allocated
2089 * array containing the set of SIDs. Set *@nel to the
2090 * number of elements in the array.
2091 */
2092
2093 int security_get_user_sids(u32 fromsid,
2094 char *username,
2095 u32 **sids,
2096 u32 *nel)
2097 {
2098 struct context *fromcon, usercon;
2099 u32 *mysids = NULL, *mysids2, sid;
2100 u32 mynel = 0, maxnel = SIDS_NEL;
2101 struct user_datum *user;
2102 struct role_datum *role;
2103 struct ebitmap_node *rnode, *tnode;
2104 int rc = 0, i, j;
2105
2106 *sids = NULL;
2107 *nel = 0;
2108
2109 if (!ss_initialized)
2110 goto out;
2111
2112 read_lock(&policy_rwlock);
2113
2114 context_init(&usercon);
2115
2116 rc = -EINVAL;
2117 fromcon = sidtab_search(&sidtab, fromsid);
2118 if (!fromcon)
2119 goto out_unlock;
2120
2121 rc = -EINVAL;
2122 user = hashtab_search(policydb.p_users.table, username);
2123 if (!user)
2124 goto out_unlock;
2125
2126 usercon.user = user->value;
2127
2128 rc = -ENOMEM;
2129 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2130 if (!mysids)
2131 goto out_unlock;
2132
2133 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2134 role = policydb.role_val_to_struct[i];
2135 usercon.role = i + 1;
2136 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2137 usercon.type = j + 1;
2138
2139 if (mls_setup_user_range(fromcon, user, &usercon))
2140 continue;
2141
2142 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2143 if (rc)
2144 goto out_unlock;
2145 if (mynel < maxnel) {
2146 mysids[mynel++] = sid;
2147 } else {
2148 rc = -ENOMEM;
2149 maxnel += SIDS_NEL;
2150 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2151 if (!mysids2)
2152 goto out_unlock;
2153 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2154 kfree(mysids);
2155 mysids = mysids2;
2156 mysids[mynel++] = sid;
2157 }
2158 }
2159 }
2160 rc = 0;
2161 out_unlock:
2162 read_unlock(&policy_rwlock);
2163 if (rc || !mynel) {
2164 kfree(mysids);
2165 goto out;
2166 }
2167
2168 rc = -ENOMEM;
2169 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2170 if (!mysids2) {
2171 kfree(mysids);
2172 goto out;
2173 }
2174 for (i = 0, j = 0; i < mynel; i++) {
2175 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2176 SECCLASS_PROCESS, /* kernel value */
2177 PROCESS__TRANSITION, AVC_STRICT,
2178 NULL);
2179 if (!rc)
2180 mysids2[j++] = mysids[i];
2181 cond_resched();
2182 }
2183 rc = 0;
2184 kfree(mysids);
2185 *sids = mysids2;
2186 *nel = j;
2187 out:
2188 return rc;
2189 }
2190
2191 /**
2192 * security_genfs_sid - Obtain a SID for a file in a filesystem
2193 * @fstype: filesystem type
2194 * @path: path from root of mount
2195 * @sclass: file security class
2196 * @sid: SID for path
2197 *
2198 * Obtain a SID to use for a file in a filesystem that
2199 * cannot support xattr or use a fixed labeling behavior like
2200 * transition SIDs or task SIDs.
2201 */
2202 int security_genfs_sid(const char *fstype,
2203 char *path,
2204 u16 orig_sclass,
2205 u32 *sid)
2206 {
2207 int len;
2208 u16 sclass;
2209 struct genfs *genfs;
2210 struct ocontext *c;
2211 int rc, cmp = 0;
2212
2213 while (path[0] == '/' && path[1] == '/')
2214 path++;
2215
2216 read_lock(&policy_rwlock);
2217
2218 sclass = unmap_class(orig_sclass);
2219 *sid = SECINITSID_UNLABELED;
2220
2221 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2222 cmp = strcmp(fstype, genfs->fstype);
2223 if (cmp <= 0)
2224 break;
2225 }
2226
2227 rc = -ENOENT;
2228 if (!genfs || cmp)
2229 goto out;
2230
2231 for (c = genfs->head; c; c = c->next) {
2232 len = strlen(c->u.name);
2233 if ((!c->v.sclass || sclass == c->v.sclass) &&
2234 (strncmp(c->u.name, path, len) == 0))
2235 break;
2236 }
2237
2238 rc = -ENOENT;
2239 if (!c)
2240 goto out;
2241
2242 if (!c->sid[0]) {
2243 rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]);
2244 if (rc)
2245 goto out;
2246 }
2247
2248 *sid = c->sid[0];
2249 rc = 0;
2250 out:
2251 read_unlock(&policy_rwlock);
2252 return rc;
2253 }
2254
2255 /**
2256 * security_fs_use - Determine how to handle labeling for a filesystem.
2257 * @fstype: filesystem type
2258 * @behavior: labeling behavior
2259 * @sid: SID for filesystem (superblock)
2260 */
2261 int security_fs_use(
2262 const char *fstype,
2263 unsigned int *behavior,
2264 u32 *sid)
2265 {
2266 int rc = 0;
2267 struct ocontext *c;
2268
2269 read_lock(&policy_rwlock);
2270
2271 c = policydb.ocontexts[OCON_FSUSE];
2272 while (c) {
2273 if (strcmp(fstype, c->u.name) == 0)
2274 break;
2275 c = c->next;
2276 }
2277
2278 if (c) {
2279 *behavior = c->v.behavior;
2280 if (!c->sid[0]) {
2281 rc = sidtab_context_to_sid(&sidtab, &c->context[0],
2282 &c->sid[0]);
2283 if (rc)
2284 goto out;
2285 }
2286 *sid = c->sid[0];
2287 } else {
2288 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
2289 if (rc) {
2290 *behavior = SECURITY_FS_USE_NONE;
2291 rc = 0;
2292 } else {
2293 *behavior = SECURITY_FS_USE_GENFS;
2294 }
2295 }
2296
2297 out:
2298 read_unlock(&policy_rwlock);
2299 return rc;
2300 }
2301
2302 int security_get_bools(int *len, char ***names, int **values)
2303 {
2304 int i, rc;
2305
2306 read_lock(&policy_rwlock);
2307 *names = NULL;
2308 *values = NULL;
2309
2310 rc = 0;
2311 *len = policydb.p_bools.nprim;
2312 if (!*len)
2313 goto out;
2314
2315 rc = -ENOMEM;
2316 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2317 if (!*names)
2318 goto err;
2319
2320 rc = -ENOMEM;
2321 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2322 if (!*values)
2323 goto err;
2324
2325 for (i = 0; i < *len; i++) {
2326 size_t name_len;
2327
2328 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2329 name_len = strlen(sym_name(&policydb, SYM_BOOLS, i)) + 1;
2330
2331 rc = -ENOMEM;
2332 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
2333 if (!(*names)[i])
2334 goto err;
2335
2336 strncpy((*names)[i], sym_name(&policydb, SYM_BOOLS, i), name_len);
2337 (*names)[i][name_len - 1] = 0;
2338 }
2339 rc = 0;
2340 out:
2341 read_unlock(&policy_rwlock);
2342 return rc;
2343 err:
2344 if (*names) {
2345 for (i = 0; i < *len; i++)
2346 kfree((*names)[i]);
2347 }
2348 kfree(*values);
2349 goto out;
2350 }
2351
2352
2353 int security_set_bools(int len, int *values)
2354 {
2355 int i, rc;
2356 int lenp, seqno = 0;
2357 struct cond_node *cur;
2358
2359 write_lock_irq(&policy_rwlock);
2360
2361 rc = -EFAULT;
2362 lenp = policydb.p_bools.nprim;
2363 if (len != lenp)
2364 goto out;
2365
2366 for (i = 0; i < len; i++) {
2367 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2368 audit_log(current->audit_context, GFP_ATOMIC,
2369 AUDIT_MAC_CONFIG_CHANGE,
2370 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2371 sym_name(&policydb, SYM_BOOLS, i),
2372 !!values[i],
2373 policydb.bool_val_to_struct[i]->state,
2374 audit_get_loginuid(current),
2375 audit_get_sessionid(current));
2376 }
2377 if (values[i])
2378 policydb.bool_val_to_struct[i]->state = 1;
2379 else
2380 policydb.bool_val_to_struct[i]->state = 0;
2381 }
2382
2383 for (cur = policydb.cond_list; cur; cur = cur->next) {
2384 rc = evaluate_cond_node(&policydb, cur);
2385 if (rc)
2386 goto out;
2387 }
2388
2389 seqno = ++latest_granting;
2390 rc = 0;
2391 out:
2392 write_unlock_irq(&policy_rwlock);
2393 if (!rc) {
2394 avc_ss_reset(seqno);
2395 selnl_notify_policyload(seqno);
2396 selinux_status_update_policyload(seqno);
2397 selinux_xfrm_notify_policyload();
2398 }
2399 return rc;
2400 }
2401
2402 int security_get_bool_value(int bool)
2403 {
2404 int rc;
2405 int len;
2406
2407 read_lock(&policy_rwlock);
2408
2409 rc = -EFAULT;
2410 len = policydb.p_bools.nprim;
2411 if (bool >= len)
2412 goto out;
2413
2414 rc = policydb.bool_val_to_struct[bool]->state;
2415 out:
2416 read_unlock(&policy_rwlock);
2417 return rc;
2418 }
2419
2420 static int security_preserve_bools(struct policydb *p)
2421 {
2422 int rc, nbools = 0, *bvalues = NULL, i;
2423 char **bnames = NULL;
2424 struct cond_bool_datum *booldatum;
2425 struct cond_node *cur;
2426
2427 rc = security_get_bools(&nbools, &bnames, &bvalues);
2428 if (rc)
2429 goto out;
2430 for (i = 0; i < nbools; i++) {
2431 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2432 if (booldatum)
2433 booldatum->state = bvalues[i];
2434 }
2435 for (cur = p->cond_list; cur; cur = cur->next) {
2436 rc = evaluate_cond_node(p, cur);
2437 if (rc)
2438 goto out;
2439 }
2440
2441 out:
2442 if (bnames) {
2443 for (i = 0; i < nbools; i++)
2444 kfree(bnames[i]);
2445 }
2446 kfree(bnames);
2447 kfree(bvalues);
2448 return rc;
2449 }
2450
2451 /*
2452 * security_sid_mls_copy() - computes a new sid based on the given
2453 * sid and the mls portion of mls_sid.
2454 */
2455 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2456 {
2457 struct context *context1;
2458 struct context *context2;
2459 struct context newcon;
2460 char *s;
2461 u32 len;
2462 int rc;
2463
2464 rc = 0;
2465 if (!ss_initialized || !policydb.mls_enabled) {
2466 *new_sid = sid;
2467 goto out;
2468 }
2469
2470 context_init(&newcon);
2471
2472 read_lock(&policy_rwlock);
2473
2474 rc = -EINVAL;
2475 context1 = sidtab_search(&sidtab, sid);
2476 if (!context1) {
2477 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2478 __func__, sid);
2479 goto out_unlock;
2480 }
2481
2482 rc = -EINVAL;
2483 context2 = sidtab_search(&sidtab, mls_sid);
2484 if (!context2) {
2485 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2486 __func__, mls_sid);
2487 goto out_unlock;
2488 }
2489
2490 newcon.user = context1->user;
2491 newcon.role = context1->role;
2492 newcon.type = context1->type;
2493 rc = mls_context_cpy(&newcon, context2);
2494 if (rc)
2495 goto out_unlock;
2496
2497 /* Check the validity of the new context. */
2498 if (!policydb_context_isvalid(&policydb, &newcon)) {
2499 rc = convert_context_handle_invalid_context(&newcon);
2500 if (rc) {
2501 if (!context_struct_to_string(&newcon, &s, &len)) {
2502 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2503 "security_sid_mls_copy: invalid context %s", s);
2504 kfree(s);
2505 }
2506 goto out_unlock;
2507 }
2508 }
2509
2510 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2511 out_unlock:
2512 read_unlock(&policy_rwlock);
2513 context_destroy(&newcon);
2514 out:
2515 return rc;
2516 }
2517
2518 /**
2519 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2520 * @nlbl_sid: NetLabel SID
2521 * @nlbl_type: NetLabel labeling protocol type
2522 * @xfrm_sid: XFRM SID
2523 *
2524 * Description:
2525 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2526 * resolved into a single SID it is returned via @peer_sid and the function
2527 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
2528 * returns a negative value. A table summarizing the behavior is below:
2529 *
2530 * | function return | @sid
2531 * ------------------------------+-----------------+-----------------
2532 * no peer labels | 0 | SECSID_NULL
2533 * single peer label | 0 | <peer_label>
2534 * multiple, consistent labels | 0 | <peer_label>
2535 * multiple, inconsistent labels | -<errno> | SECSID_NULL
2536 *
2537 */
2538 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2539 u32 xfrm_sid,
2540 u32 *peer_sid)
2541 {
2542 int rc;
2543 struct context *nlbl_ctx;
2544 struct context *xfrm_ctx;
2545
2546 *peer_sid = SECSID_NULL;
2547
2548 /* handle the common (which also happens to be the set of easy) cases
2549 * right away, these two if statements catch everything involving a
2550 * single or absent peer SID/label */
2551 if (xfrm_sid == SECSID_NULL) {
2552 *peer_sid = nlbl_sid;
2553 return 0;
2554 }
2555 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2556 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2557 * is present */
2558 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2559 *peer_sid = xfrm_sid;
2560 return 0;
2561 }
2562
2563 /* we don't need to check ss_initialized here since the only way both
2564 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2565 * security server was initialized and ss_initialized was true */
2566 if (!policydb.mls_enabled)
2567 return 0;
2568
2569 read_lock(&policy_rwlock);
2570
2571 rc = -EINVAL;
2572 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2573 if (!nlbl_ctx) {
2574 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2575 __func__, nlbl_sid);
2576 goto out;
2577 }
2578 rc = -EINVAL;
2579 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2580 if (!xfrm_ctx) {
2581 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2582 __func__, xfrm_sid);
2583 goto out;
2584 }
2585 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2586 if (rc)
2587 goto out;
2588
2589 /* at present NetLabel SIDs/labels really only carry MLS
2590 * information so if the MLS portion of the NetLabel SID
2591 * matches the MLS portion of the labeled XFRM SID/label
2592 * then pass along the XFRM SID as it is the most
2593 * expressive */
2594 *peer_sid = xfrm_sid;
2595 out:
2596 read_unlock(&policy_rwlock);
2597 return rc;
2598 }
2599
2600 static int get_classes_callback(void *k, void *d, void *args)
2601 {
2602 struct class_datum *datum = d;
2603 char *name = k, **classes = args;
2604 int value = datum->value - 1;
2605
2606 classes[value] = kstrdup(name, GFP_ATOMIC);
2607 if (!classes[value])
2608 return -ENOMEM;
2609
2610 return 0;
2611 }
2612
2613 int security_get_classes(char ***classes, int *nclasses)
2614 {
2615 int rc;
2616
2617 read_lock(&policy_rwlock);
2618
2619 rc = -ENOMEM;
2620 *nclasses = policydb.p_classes.nprim;
2621 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
2622 if (!*classes)
2623 goto out;
2624
2625 rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2626 *classes);
2627 if (rc) {
2628 int i;
2629 for (i = 0; i < *nclasses; i++)
2630 kfree((*classes)[i]);
2631 kfree(*classes);
2632 }
2633
2634 out:
2635 read_unlock(&policy_rwlock);
2636 return rc;
2637 }
2638
2639 static int get_permissions_callback(void *k, void *d, void *args)
2640 {
2641 struct perm_datum *datum = d;
2642 char *name = k, **perms = args;
2643 int value = datum->value - 1;
2644
2645 perms[value] = kstrdup(name, GFP_ATOMIC);
2646 if (!perms[value])
2647 return -ENOMEM;
2648
2649 return 0;
2650 }
2651
2652 int security_get_permissions(char *class, char ***perms, int *nperms)
2653 {
2654 int rc, i;
2655 struct class_datum *match;
2656
2657 read_lock(&policy_rwlock);
2658
2659 rc = -EINVAL;
2660 match = hashtab_search(policydb.p_classes.table, class);
2661 if (!match) {
2662 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
2663 __func__, class);
2664 goto out;
2665 }
2666
2667 rc = -ENOMEM;
2668 *nperms = match->permissions.nprim;
2669 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
2670 if (!*perms)
2671 goto out;
2672
2673 if (match->comdatum) {
2674 rc = hashtab_map(match->comdatum->permissions.table,
2675 get_permissions_callback, *perms);
2676 if (rc)
2677 goto err;
2678 }
2679
2680 rc = hashtab_map(match->permissions.table, get_permissions_callback,
2681 *perms);
2682 if (rc)
2683 goto err;
2684
2685 out:
2686 read_unlock(&policy_rwlock);
2687 return rc;
2688
2689 err:
2690 read_unlock(&policy_rwlock);
2691 for (i = 0; i < *nperms; i++)
2692 kfree((*perms)[i]);
2693 kfree(*perms);
2694 return rc;
2695 }
2696
2697 int security_get_reject_unknown(void)
2698 {
2699 return policydb.reject_unknown;
2700 }
2701
2702 int security_get_allow_unknown(void)
2703 {
2704 return policydb.allow_unknown;
2705 }
2706
2707 /**
2708 * security_policycap_supported - Check for a specific policy capability
2709 * @req_cap: capability
2710 *
2711 * Description:
2712 * This function queries the currently loaded policy to see if it supports the
2713 * capability specified by @req_cap. Returns true (1) if the capability is
2714 * supported, false (0) if it isn't supported.
2715 *
2716 */
2717 int security_policycap_supported(unsigned int req_cap)
2718 {
2719 int rc;
2720
2721 read_lock(&policy_rwlock);
2722 rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2723 read_unlock(&policy_rwlock);
2724
2725 return rc;
2726 }
2727
2728 struct selinux_audit_rule {
2729 u32 au_seqno;
2730 struct context au_ctxt;
2731 };
2732
2733 void selinux_audit_rule_free(void *vrule)
2734 {
2735 struct selinux_audit_rule *rule = vrule;
2736
2737 if (rule) {
2738 context_destroy(&rule->au_ctxt);
2739 kfree(rule);
2740 }
2741 }
2742
2743 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2744 {
2745 struct selinux_audit_rule *tmprule;
2746 struct role_datum *roledatum;
2747 struct type_datum *typedatum;
2748 struct user_datum *userdatum;
2749 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2750 int rc = 0;
2751
2752 *rule = NULL;
2753
2754 if (!ss_initialized)
2755 return -EOPNOTSUPP;
2756
2757 switch (field) {
2758 case AUDIT_SUBJ_USER:
2759 case AUDIT_SUBJ_ROLE:
2760 case AUDIT_SUBJ_TYPE:
2761 case AUDIT_OBJ_USER:
2762 case AUDIT_OBJ_ROLE:
2763 case AUDIT_OBJ_TYPE:
2764 /* only 'equals' and 'not equals' fit user, role, and type */
2765 if (op != Audit_equal && op != Audit_not_equal)
2766 return -EINVAL;
2767 break;
2768 case AUDIT_SUBJ_SEN:
2769 case AUDIT_SUBJ_CLR:
2770 case AUDIT_OBJ_LEV_LOW:
2771 case AUDIT_OBJ_LEV_HIGH:
2772 /* we do not allow a range, indicated by the presense of '-' */
2773 if (strchr(rulestr, '-'))
2774 return -EINVAL;
2775 break;
2776 default:
2777 /* only the above fields are valid */
2778 return -EINVAL;
2779 }
2780
2781 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2782 if (!tmprule)
2783 return -ENOMEM;
2784
2785 context_init(&tmprule->au_ctxt);
2786
2787 read_lock(&policy_rwlock);
2788
2789 tmprule->au_seqno = latest_granting;
2790
2791 switch (field) {
2792 case AUDIT_SUBJ_USER:
2793 case AUDIT_OBJ_USER:
2794 rc = -EINVAL;
2795 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2796 if (!userdatum)
2797 goto out;
2798 tmprule->au_ctxt.user = userdatum->value;
2799 break;
2800 case AUDIT_SUBJ_ROLE:
2801 case AUDIT_OBJ_ROLE:
2802 rc = -EINVAL;
2803 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2804 if (!roledatum)
2805 goto out;
2806 tmprule->au_ctxt.role = roledatum->value;
2807 break;
2808 case AUDIT_SUBJ_TYPE:
2809 case AUDIT_OBJ_TYPE:
2810 rc = -EINVAL;
2811 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2812 if (!typedatum)
2813 goto out;
2814 tmprule->au_ctxt.type = typedatum->value;
2815 break;
2816 case AUDIT_SUBJ_SEN:
2817 case AUDIT_SUBJ_CLR:
2818 case AUDIT_OBJ_LEV_LOW:
2819 case AUDIT_OBJ_LEV_HIGH:
2820 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2821 if (rc)
2822 goto out;
2823 break;
2824 }
2825 rc = 0;
2826 out:
2827 read_unlock(&policy_rwlock);
2828
2829 if (rc) {
2830 selinux_audit_rule_free(tmprule);
2831 tmprule = NULL;
2832 }
2833
2834 *rule = tmprule;
2835
2836 return rc;
2837 }
2838
2839 /* Check to see if the rule contains any selinux fields */
2840 int selinux_audit_rule_known(struct audit_krule *rule)
2841 {
2842 int i;
2843
2844 for (i = 0; i < rule->field_count; i++) {
2845 struct audit_field *f = &rule->fields[i];
2846 switch (f->type) {
2847 case AUDIT_SUBJ_USER:
2848 case AUDIT_SUBJ_ROLE:
2849 case AUDIT_SUBJ_TYPE:
2850 case AUDIT_SUBJ_SEN:
2851 case AUDIT_SUBJ_CLR:
2852 case AUDIT_OBJ_USER:
2853 case AUDIT_OBJ_ROLE:
2854 case AUDIT_OBJ_TYPE:
2855 case AUDIT_OBJ_LEV_LOW:
2856 case AUDIT_OBJ_LEV_HIGH:
2857 return 1;
2858 }
2859 }
2860
2861 return 0;
2862 }
2863
2864 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2865 struct audit_context *actx)
2866 {
2867 struct context *ctxt;
2868 struct mls_level *level;
2869 struct selinux_audit_rule *rule = vrule;
2870 int match = 0;
2871
2872 if (!rule) {
2873 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2874 "selinux_audit_rule_match: missing rule\n");
2875 return -ENOENT;
2876 }
2877
2878 read_lock(&policy_rwlock);
2879
2880 if (rule->au_seqno < latest_granting) {
2881 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2882 "selinux_audit_rule_match: stale rule\n");
2883 match = -ESTALE;
2884 goto out;
2885 }
2886
2887 ctxt = sidtab_search(&sidtab, sid);
2888 if (!ctxt) {
2889 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2890 "selinux_audit_rule_match: unrecognized SID %d\n",
2891 sid);
2892 match = -ENOENT;
2893 goto out;
2894 }
2895
2896 /* a field/op pair that is not caught here will simply fall through
2897 without a match */
2898 switch (field) {
2899 case AUDIT_SUBJ_USER:
2900 case AUDIT_OBJ_USER:
2901 switch (op) {
2902 case Audit_equal:
2903 match = (ctxt->user == rule->au_ctxt.user);
2904 break;
2905 case Audit_not_equal:
2906 match = (ctxt->user != rule->au_ctxt.user);
2907 break;
2908 }
2909 break;
2910 case AUDIT_SUBJ_ROLE:
2911 case AUDIT_OBJ_ROLE:
2912 switch (op) {
2913 case Audit_equal:
2914 match = (ctxt->role == rule->au_ctxt.role);
2915 break;
2916 case Audit_not_equal:
2917 match = (ctxt->role != rule->au_ctxt.role);
2918 break;
2919 }
2920 break;
2921 case AUDIT_SUBJ_TYPE:
2922 case AUDIT_OBJ_TYPE:
2923 switch (op) {
2924 case Audit_equal:
2925 match = (ctxt->type == rule->au_ctxt.type);
2926 break;
2927 case Audit_not_equal:
2928 match = (ctxt->type != rule->au_ctxt.type);
2929 break;
2930 }
2931 break;
2932 case AUDIT_SUBJ_SEN:
2933 case AUDIT_SUBJ_CLR:
2934 case AUDIT_OBJ_LEV_LOW:
2935 case AUDIT_OBJ_LEV_HIGH:
2936 level = ((field == AUDIT_SUBJ_SEN ||
2937 field == AUDIT_OBJ_LEV_LOW) ?
2938 &ctxt->range.level[0] : &ctxt->range.level[1]);
2939 switch (op) {
2940 case Audit_equal:
2941 match = mls_level_eq(&rule->au_ctxt.range.level[0],
2942 level);
2943 break;
2944 case Audit_not_equal:
2945 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2946 level);
2947 break;
2948 case Audit_lt:
2949 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2950 level) &&
2951 !mls_level_eq(&rule->au_ctxt.range.level[0],
2952 level));
2953 break;
2954 case Audit_le:
2955 match = mls_level_dom(&rule->au_ctxt.range.level[0],
2956 level);
2957 break;
2958 case Audit_gt:
2959 match = (mls_level_dom(level,
2960 &rule->au_ctxt.range.level[0]) &&
2961 !mls_level_eq(level,
2962 &rule->au_ctxt.range.level[0]));
2963 break;
2964 case Audit_ge:
2965 match = mls_level_dom(level,
2966 &rule->au_ctxt.range.level[0]);
2967 break;
2968 }
2969 }
2970
2971 out:
2972 read_unlock(&policy_rwlock);
2973 return match;
2974 }
2975
2976 static int (*aurule_callback)(void) = audit_update_lsm_rules;
2977
2978 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
2979 u16 class, u32 perms, u32 *retained)
2980 {
2981 int err = 0;
2982
2983 if (event == AVC_CALLBACK_RESET && aurule_callback)
2984 err = aurule_callback();
2985 return err;
2986 }
2987
2988 static int __init aurule_init(void)
2989 {
2990 int err;
2991
2992 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
2993 SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
2994 if (err)
2995 panic("avc_add_callback() failed, error %d\n", err);
2996
2997 return err;
2998 }
2999 __initcall(aurule_init);
3000
3001 #ifdef CONFIG_NETLABEL
3002 /**
3003 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3004 * @secattr: the NetLabel packet security attributes
3005 * @sid: the SELinux SID
3006 *
3007 * Description:
3008 * Attempt to cache the context in @ctx, which was derived from the packet in
3009 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3010 * already been initialized.
3011 *
3012 */
3013 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3014 u32 sid)
3015 {
3016 u32 *sid_cache;
3017
3018 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3019 if (sid_cache == NULL)
3020 return;
3021 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3022 if (secattr->cache == NULL) {
3023 kfree(sid_cache);
3024 return;
3025 }
3026
3027 *sid_cache = sid;
3028 secattr->cache->free = kfree;
3029 secattr->cache->data = sid_cache;
3030 secattr->flags |= NETLBL_SECATTR_CACHE;
3031 }
3032
3033 /**
3034 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3035 * @secattr: the NetLabel packet security attributes
3036 * @sid: the SELinux SID
3037 *
3038 * Description:
3039 * Convert the given NetLabel security attributes in @secattr into a
3040 * SELinux SID. If the @secattr field does not contain a full SELinux
3041 * SID/context then use SECINITSID_NETMSG as the foundation. If possibile the
3042 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3043 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3044 * conversion for future lookups. Returns zero on success, negative values on
3045 * failure.
3046 *
3047 */
3048 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3049 u32 *sid)
3050 {
3051 int rc;
3052 struct context *ctx;
3053 struct context ctx_new;
3054
3055 if (!ss_initialized) {
3056 *sid = SECSID_NULL;
3057 return 0;
3058 }
3059
3060 read_lock(&policy_rwlock);
3061
3062 if (secattr->flags & NETLBL_SECATTR_CACHE)
3063 *sid = *(u32 *)secattr->cache->data;
3064 else if (secattr->flags & NETLBL_SECATTR_SECID)
3065 *sid = secattr->attr.secid;
3066 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3067 rc = -EIDRM;
3068 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3069 if (ctx == NULL)
3070 goto out;
3071
3072 context_init(&ctx_new);
3073 ctx_new.user = ctx->user;
3074 ctx_new.role = ctx->role;
3075 ctx_new.type = ctx->type;
3076 mls_import_netlbl_lvl(&ctx_new, secattr);
3077 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3078 rc = ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
3079 secattr->attr.mls.cat);
3080 if (rc)
3081 goto out;
3082 memcpy(&ctx_new.range.level[1].cat,
3083 &ctx_new.range.level[0].cat,
3084 sizeof(ctx_new.range.level[0].cat));
3085 }
3086 rc = -EIDRM;
3087 if (!mls_context_isvalid(&policydb, &ctx_new))
3088 goto out_free;
3089
3090 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3091 if (rc)
3092 goto out_free;
3093
3094 security_netlbl_cache_add(secattr, *sid);
3095
3096 ebitmap_destroy(&ctx_new.range.level[0].cat);
3097 } else
3098 *sid = SECSID_NULL;
3099
3100 read_unlock(&policy_rwlock);
3101 return 0;
3102 out_free:
3103 ebitmap_destroy(&ctx_new.range.level[0].cat);
3104 out:
3105 read_unlock(&policy_rwlock);
3106 return rc;
3107 }
3108
3109 /**
3110 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3111 * @sid: the SELinux SID
3112 * @secattr: the NetLabel packet security attributes
3113 *
3114 * Description:
3115 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3116 * Returns zero on success, negative values on failure.
3117 *
3118 */
3119 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3120 {
3121 int rc;
3122 struct context *ctx;
3123
3124 if (!ss_initialized)
3125 return 0;
3126
3127 read_lock(&policy_rwlock);
3128
3129 rc = -ENOENT;
3130 ctx = sidtab_search(&sidtab, sid);
3131 if (ctx == NULL)
3132 goto out;
3133
3134 rc = -ENOMEM;
3135 secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1),
3136 GFP_ATOMIC);
3137 if (secattr->domain == NULL)
3138 goto out;
3139
3140 secattr->attr.secid = sid;
3141 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3142 mls_export_netlbl_lvl(ctx, secattr);
3143 rc = mls_export_netlbl_cat(ctx, secattr);
3144 out:
3145 read_unlock(&policy_rwlock);
3146 return rc;
3147 }
3148 #endif /* CONFIG_NETLABEL */
3149
3150 /**
3151 * security_read_policy - read the policy.
3152 * @data: binary policy data
3153 * @len: length of data in bytes
3154 *
3155 */
3156 int security_read_policy(void **data, ssize_t *len)
3157 {
3158 int rc;
3159 struct policy_file fp;
3160
3161 if (!ss_initialized)
3162 return -EINVAL;
3163
3164 *len = security_policydb_len();
3165
3166 *data = vmalloc_user(*len);
3167 if (!*data)
3168 return -ENOMEM;
3169
3170 fp.data = *data;
3171 fp.len = *len;
3172
3173 read_lock(&policy_rwlock);
3174 rc = policydb_write(&policydb, &fp);
3175 read_unlock(&policy_rwlock);
3176
3177 if (rc)
3178 return rc;
3179
3180 *len = (unsigned long)fp.data - (unsigned long)*data;
3181 return 0;
3182
3183 }
Linux kernel - Deliverables
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