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[GitHub/mt8127/android_kernel_alcatel_ttab.git] / security / selinux / ss / services.c
1 /*
2 * Implementation of the security services.
3 *
4 * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
5 * James Morris <jmorris@redhat.com>
6 *
7 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
8 *
9 * Support for enhanced MLS infrastructure.
10 *
11 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
12 *
13 * Added conditional policy language extensions
14 *
15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
16 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
17 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
18 * This program is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License as published by
20 * the Free Software Foundation, version 2.
21 */
22 #include <linux/kernel.h>
23 #include <linux/slab.h>
24 #include <linux/string.h>
25 #include <linux/spinlock.h>
26 #include <linux/errno.h>
27 #include <linux/in.h>
28 #include <linux/sched.h>
29 #include <linux/audit.h>
30 #include <asm/semaphore.h>
31 #include "flask.h"
32 #include "avc.h"
33 #include "avc_ss.h"
34 #include "security.h"
35 #include "context.h"
36 #include "policydb.h"
37 #include "sidtab.h"
38 #include "services.h"
39 #include "conditional.h"
40 #include "mls.h"
41
42 extern void selnl_notify_policyload(u32 seqno);
43 unsigned int policydb_loaded_version;
44
45 static DEFINE_RWLOCK(policy_rwlock);
46 #define POLICY_RDLOCK read_lock(&policy_rwlock)
47 #define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
48 #define POLICY_RDUNLOCK read_unlock(&policy_rwlock)
49 #define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock)
50
51 static DECLARE_MUTEX(load_sem);
52 #define LOAD_LOCK down(&load_sem)
53 #define LOAD_UNLOCK up(&load_sem)
54
55 static struct sidtab sidtab;
56 struct policydb policydb;
57 int ss_initialized = 0;
58
59 /*
60 * The largest sequence number that has been used when
61 * providing an access decision to the access vector cache.
62 * The sequence number only changes when a policy change
63 * occurs.
64 */
65 static u32 latest_granting = 0;
66
67 /* Forward declaration. */
68 static int context_struct_to_string(struct context *context, char **scontext,
69 u32 *scontext_len);
70
71 /*
72 * Return the boolean value of a constraint expression
73 * when it is applied to the specified source and target
74 * security contexts.
75 *
76 * xcontext is a special beast... It is used by the validatetrans rules
77 * only. For these rules, scontext is the context before the transition,
78 * tcontext is the context after the transition, and xcontext is the context
79 * of the process performing the transition. All other callers of
80 * constraint_expr_eval should pass in NULL for xcontext.
81 */
82 static int constraint_expr_eval(struct context *scontext,
83 struct context *tcontext,
84 struct context *xcontext,
85 struct constraint_expr *cexpr)
86 {
87 u32 val1, val2;
88 struct context *c;
89 struct role_datum *r1, *r2;
90 struct mls_level *l1, *l2;
91 struct constraint_expr *e;
92 int s[CEXPR_MAXDEPTH];
93 int sp = -1;
94
95 for (e = cexpr; e; e = e->next) {
96 switch (e->expr_type) {
97 case CEXPR_NOT:
98 BUG_ON(sp < 0);
99 s[sp] = !s[sp];
100 break;
101 case CEXPR_AND:
102 BUG_ON(sp < 1);
103 sp--;
104 s[sp] &= s[sp+1];
105 break;
106 case CEXPR_OR:
107 BUG_ON(sp < 1);
108 sp--;
109 s[sp] |= s[sp+1];
110 break;
111 case CEXPR_ATTR:
112 if (sp == (CEXPR_MAXDEPTH-1))
113 return 0;
114 switch (e->attr) {
115 case CEXPR_USER:
116 val1 = scontext->user;
117 val2 = tcontext->user;
118 break;
119 case CEXPR_TYPE:
120 val1 = scontext->type;
121 val2 = tcontext->type;
122 break;
123 case CEXPR_ROLE:
124 val1 = scontext->role;
125 val2 = tcontext->role;
126 r1 = policydb.role_val_to_struct[val1 - 1];
127 r2 = policydb.role_val_to_struct[val2 - 1];
128 switch (e->op) {
129 case CEXPR_DOM:
130 s[++sp] = ebitmap_get_bit(&r1->dominates,
131 val2 - 1);
132 continue;
133 case CEXPR_DOMBY:
134 s[++sp] = ebitmap_get_bit(&r2->dominates,
135 val1 - 1);
136 continue;
137 case CEXPR_INCOMP:
138 s[++sp] = ( !ebitmap_get_bit(&r1->dominates,
139 val2 - 1) &&
140 !ebitmap_get_bit(&r2->dominates,
141 val1 - 1) );
142 continue;
143 default:
144 break;
145 }
146 break;
147 case CEXPR_L1L2:
148 l1 = &(scontext->range.level[0]);
149 l2 = &(tcontext->range.level[0]);
150 goto mls_ops;
151 case CEXPR_L1H2:
152 l1 = &(scontext->range.level[0]);
153 l2 = &(tcontext->range.level[1]);
154 goto mls_ops;
155 case CEXPR_H1L2:
156 l1 = &(scontext->range.level[1]);
157 l2 = &(tcontext->range.level[0]);
158 goto mls_ops;
159 case CEXPR_H1H2:
160 l1 = &(scontext->range.level[1]);
161 l2 = &(tcontext->range.level[1]);
162 goto mls_ops;
163 case CEXPR_L1H1:
164 l1 = &(scontext->range.level[0]);
165 l2 = &(scontext->range.level[1]);
166 goto mls_ops;
167 case CEXPR_L2H2:
168 l1 = &(tcontext->range.level[0]);
169 l2 = &(tcontext->range.level[1]);
170 goto mls_ops;
171 mls_ops:
172 switch (e->op) {
173 case CEXPR_EQ:
174 s[++sp] = mls_level_eq(l1, l2);
175 continue;
176 case CEXPR_NEQ:
177 s[++sp] = !mls_level_eq(l1, l2);
178 continue;
179 case CEXPR_DOM:
180 s[++sp] = mls_level_dom(l1, l2);
181 continue;
182 case CEXPR_DOMBY:
183 s[++sp] = mls_level_dom(l2, l1);
184 continue;
185 case CEXPR_INCOMP:
186 s[++sp] = mls_level_incomp(l2, l1);
187 continue;
188 default:
189 BUG();
190 return 0;
191 }
192 break;
193 default:
194 BUG();
195 return 0;
196 }
197
198 switch (e->op) {
199 case CEXPR_EQ:
200 s[++sp] = (val1 == val2);
201 break;
202 case CEXPR_NEQ:
203 s[++sp] = (val1 != val2);
204 break;
205 default:
206 BUG();
207 return 0;
208 }
209 break;
210 case CEXPR_NAMES:
211 if (sp == (CEXPR_MAXDEPTH-1))
212 return 0;
213 c = scontext;
214 if (e->attr & CEXPR_TARGET)
215 c = tcontext;
216 else if (e->attr & CEXPR_XTARGET) {
217 c = xcontext;
218 if (!c) {
219 BUG();
220 return 0;
221 }
222 }
223 if (e->attr & CEXPR_USER)
224 val1 = c->user;
225 else if (e->attr & CEXPR_ROLE)
226 val1 = c->role;
227 else if (e->attr & CEXPR_TYPE)
228 val1 = c->type;
229 else {
230 BUG();
231 return 0;
232 }
233
234 switch (e->op) {
235 case CEXPR_EQ:
236 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
237 break;
238 case CEXPR_NEQ:
239 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
240 break;
241 default:
242 BUG();
243 return 0;
244 }
245 break;
246 default:
247 BUG();
248 return 0;
249 }
250 }
251
252 BUG_ON(sp != 0);
253 return s[0];
254 }
255
256 /*
257 * Compute access vectors based on a context structure pair for
258 * the permissions in a particular class.
259 */
260 static int context_struct_compute_av(struct context *scontext,
261 struct context *tcontext,
262 u16 tclass,
263 u32 requested,
264 struct av_decision *avd)
265 {
266 struct constraint_node *constraint;
267 struct role_allow *ra;
268 struct avtab_key avkey;
269 struct avtab_node *node;
270 struct class_datum *tclass_datum;
271 struct ebitmap *sattr, *tattr;
272 struct ebitmap_node *snode, *tnode;
273 unsigned int i, j;
274
275 /*
276 * Remap extended Netlink classes for old policy versions.
277 * Do this here rather than socket_type_to_security_class()
278 * in case a newer policy version is loaded, allowing sockets
279 * to remain in the correct class.
280 */
281 if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
282 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
283 tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
284 tclass = SECCLASS_NETLINK_SOCKET;
285
286 if (!tclass || tclass > policydb.p_classes.nprim) {
287 printk(KERN_ERR "security_compute_av: unrecognized class %d\n",
288 tclass);
289 return -EINVAL;
290 }
291 tclass_datum = policydb.class_val_to_struct[tclass - 1];
292
293 /*
294 * Initialize the access vectors to the default values.
295 */
296 avd->allowed = 0;
297 avd->decided = 0xffffffff;
298 avd->auditallow = 0;
299 avd->auditdeny = 0xffffffff;
300 avd->seqno = latest_granting;
301
302 /*
303 * If a specific type enforcement rule was defined for
304 * this permission check, then use it.
305 */
306 avkey.target_class = tclass;
307 avkey.specified = AVTAB_AV;
308 sattr = &policydb.type_attr_map[scontext->type - 1];
309 tattr = &policydb.type_attr_map[tcontext->type - 1];
310 ebitmap_for_each_bit(sattr, snode, i) {
311 if (!ebitmap_node_get_bit(snode, i))
312 continue;
313 ebitmap_for_each_bit(tattr, tnode, j) {
314 if (!ebitmap_node_get_bit(tnode, j))
315 continue;
316 avkey.source_type = i + 1;
317 avkey.target_type = j + 1;
318 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
319 node != NULL;
320 node = avtab_search_node_next(node, avkey.specified)) {
321 if (node->key.specified == AVTAB_ALLOWED)
322 avd->allowed |= node->datum.data;
323 else if (node->key.specified == AVTAB_AUDITALLOW)
324 avd->auditallow |= node->datum.data;
325 else if (node->key.specified == AVTAB_AUDITDENY)
326 avd->auditdeny &= node->datum.data;
327 }
328
329 /* Check conditional av table for additional permissions */
330 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
331
332 }
333 }
334
335 /*
336 * Remove any permissions prohibited by a constraint (this includes
337 * the MLS policy).
338 */
339 constraint = tclass_datum->constraints;
340 while (constraint) {
341 if ((constraint->permissions & (avd->allowed)) &&
342 !constraint_expr_eval(scontext, tcontext, NULL,
343 constraint->expr)) {
344 avd->allowed = (avd->allowed) & ~(constraint->permissions);
345 }
346 constraint = constraint->next;
347 }
348
349 /*
350 * If checking process transition permission and the
351 * role is changing, then check the (current_role, new_role)
352 * pair.
353 */
354 if (tclass == SECCLASS_PROCESS &&
355 (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
356 scontext->role != tcontext->role) {
357 for (ra = policydb.role_allow; ra; ra = ra->next) {
358 if (scontext->role == ra->role &&
359 tcontext->role == ra->new_role)
360 break;
361 }
362 if (!ra)
363 avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
364 PROCESS__DYNTRANSITION);
365 }
366
367 return 0;
368 }
369
370 static int security_validtrans_handle_fail(struct context *ocontext,
371 struct context *ncontext,
372 struct context *tcontext,
373 u16 tclass)
374 {
375 char *o = NULL, *n = NULL, *t = NULL;
376 u32 olen, nlen, tlen;
377
378 if (context_struct_to_string(ocontext, &o, &olen) < 0)
379 goto out;
380 if (context_struct_to_string(ncontext, &n, &nlen) < 0)
381 goto out;
382 if (context_struct_to_string(tcontext, &t, &tlen) < 0)
383 goto out;
384 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
385 "security_validate_transition: denied for"
386 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
387 o, n, t, policydb.p_class_val_to_name[tclass-1]);
388 out:
389 kfree(o);
390 kfree(n);
391 kfree(t);
392
393 if (!selinux_enforcing)
394 return 0;
395 return -EPERM;
396 }
397
398 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
399 u16 tclass)
400 {
401 struct context *ocontext;
402 struct context *ncontext;
403 struct context *tcontext;
404 struct class_datum *tclass_datum;
405 struct constraint_node *constraint;
406 int rc = 0;
407
408 if (!ss_initialized)
409 return 0;
410
411 POLICY_RDLOCK;
412
413 /*
414 * Remap extended Netlink classes for old policy versions.
415 * Do this here rather than socket_type_to_security_class()
416 * in case a newer policy version is loaded, allowing sockets
417 * to remain in the correct class.
418 */
419 if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
420 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
421 tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
422 tclass = SECCLASS_NETLINK_SOCKET;
423
424 if (!tclass || tclass > policydb.p_classes.nprim) {
425 printk(KERN_ERR "security_validate_transition: "
426 "unrecognized class %d\n", tclass);
427 rc = -EINVAL;
428 goto out;
429 }
430 tclass_datum = policydb.class_val_to_struct[tclass - 1];
431
432 ocontext = sidtab_search(&sidtab, oldsid);
433 if (!ocontext) {
434 printk(KERN_ERR "security_validate_transition: "
435 " unrecognized SID %d\n", oldsid);
436 rc = -EINVAL;
437 goto out;
438 }
439
440 ncontext = sidtab_search(&sidtab, newsid);
441 if (!ncontext) {
442 printk(KERN_ERR "security_validate_transition: "
443 " unrecognized SID %d\n", newsid);
444 rc = -EINVAL;
445 goto out;
446 }
447
448 tcontext = sidtab_search(&sidtab, tasksid);
449 if (!tcontext) {
450 printk(KERN_ERR "security_validate_transition: "
451 " unrecognized SID %d\n", tasksid);
452 rc = -EINVAL;
453 goto out;
454 }
455
456 constraint = tclass_datum->validatetrans;
457 while (constraint) {
458 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
459 constraint->expr)) {
460 rc = security_validtrans_handle_fail(ocontext, ncontext,
461 tcontext, tclass);
462 goto out;
463 }
464 constraint = constraint->next;
465 }
466
467 out:
468 POLICY_RDUNLOCK;
469 return rc;
470 }
471
472 /**
473 * security_compute_av - Compute access vector decisions.
474 * @ssid: source security identifier
475 * @tsid: target security identifier
476 * @tclass: target security class
477 * @requested: requested permissions
478 * @avd: access vector decisions
479 *
480 * Compute a set of access vector decisions based on the
481 * SID pair (@ssid, @tsid) for the permissions in @tclass.
482 * Return -%EINVAL if any of the parameters are invalid or %0
483 * if the access vector decisions were computed successfully.
484 */
485 int security_compute_av(u32 ssid,
486 u32 tsid,
487 u16 tclass,
488 u32 requested,
489 struct av_decision *avd)
490 {
491 struct context *scontext = NULL, *tcontext = NULL;
492 int rc = 0;
493
494 if (!ss_initialized) {
495 avd->allowed = 0xffffffff;
496 avd->decided = 0xffffffff;
497 avd->auditallow = 0;
498 avd->auditdeny = 0xffffffff;
499 avd->seqno = latest_granting;
500 return 0;
501 }
502
503 POLICY_RDLOCK;
504
505 scontext = sidtab_search(&sidtab, ssid);
506 if (!scontext) {
507 printk(KERN_ERR "security_compute_av: unrecognized SID %d\n",
508 ssid);
509 rc = -EINVAL;
510 goto out;
511 }
512 tcontext = sidtab_search(&sidtab, tsid);
513 if (!tcontext) {
514 printk(KERN_ERR "security_compute_av: unrecognized SID %d\n",
515 tsid);
516 rc = -EINVAL;
517 goto out;
518 }
519
520 rc = context_struct_compute_av(scontext, tcontext, tclass,
521 requested, avd);
522 out:
523 POLICY_RDUNLOCK;
524 return rc;
525 }
526
527 /*
528 * Write the security context string representation of
529 * the context structure `context' into a dynamically
530 * allocated string of the correct size. Set `*scontext'
531 * to point to this string and set `*scontext_len' to
532 * the length of the string.
533 */
534 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
535 {
536 char *scontextp;
537
538 *scontext = NULL;
539 *scontext_len = 0;
540
541 /* Compute the size of the context. */
542 *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
543 *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
544 *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
545 *scontext_len += mls_compute_context_len(context);
546
547 /* Allocate space for the context; caller must free this space. */
548 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
549 if (!scontextp) {
550 return -ENOMEM;
551 }
552 *scontext = scontextp;
553
554 /*
555 * Copy the user name, role name and type name into the context.
556 */
557 sprintf(scontextp, "%s:%s:%s",
558 policydb.p_user_val_to_name[context->user - 1],
559 policydb.p_role_val_to_name[context->role - 1],
560 policydb.p_type_val_to_name[context->type - 1]);
561 scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
562 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
563 1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
564
565 mls_sid_to_context(context, &scontextp);
566
567 *scontextp = 0;
568
569 return 0;
570 }
571
572 #include "initial_sid_to_string.h"
573
574 /**
575 * security_sid_to_context - Obtain a context for a given SID.
576 * @sid: security identifier, SID
577 * @scontext: security context
578 * @scontext_len: length in bytes
579 *
580 * Write the string representation of the context associated with @sid
581 * into a dynamically allocated string of the correct size. Set @scontext
582 * to point to this string and set @scontext_len to the length of the string.
583 */
584 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
585 {
586 struct context *context;
587 int rc = 0;
588
589 if (!ss_initialized) {
590 if (sid <= SECINITSID_NUM) {
591 char *scontextp;
592
593 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
594 scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
595 strcpy(scontextp, initial_sid_to_string[sid]);
596 *scontext = scontextp;
597 goto out;
598 }
599 printk(KERN_ERR "security_sid_to_context: called before initial "
600 "load_policy on unknown SID %d\n", sid);
601 rc = -EINVAL;
602 goto out;
603 }
604 POLICY_RDLOCK;
605 context = sidtab_search(&sidtab, sid);
606 if (!context) {
607 printk(KERN_ERR "security_sid_to_context: unrecognized SID "
608 "%d\n", sid);
609 rc = -EINVAL;
610 goto out_unlock;
611 }
612 rc = context_struct_to_string(context, scontext, scontext_len);
613 out_unlock:
614 POLICY_RDUNLOCK;
615 out:
616 return rc;
617
618 }
619
620 static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
621 {
622 char *scontext2;
623 struct context context;
624 struct role_datum *role;
625 struct type_datum *typdatum;
626 struct user_datum *usrdatum;
627 char *scontextp, *p, oldc;
628 int rc = 0;
629
630 if (!ss_initialized) {
631 int i;
632
633 for (i = 1; i < SECINITSID_NUM; i++) {
634 if (!strcmp(initial_sid_to_string[i], scontext)) {
635 *sid = i;
636 goto out;
637 }
638 }
639 *sid = SECINITSID_KERNEL;
640 goto out;
641 }
642 *sid = SECSID_NULL;
643
644 /* Copy the string so that we can modify the copy as we parse it.
645 The string should already by null terminated, but we append a
646 null suffix to the copy to avoid problems with the existing
647 attr package, which doesn't view the null terminator as part
648 of the attribute value. */
649 scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
650 if (!scontext2) {
651 rc = -ENOMEM;
652 goto out;
653 }
654 memcpy(scontext2, scontext, scontext_len);
655 scontext2[scontext_len] = 0;
656
657 context_init(&context);
658 *sid = SECSID_NULL;
659
660 POLICY_RDLOCK;
661
662 /* Parse the security context. */
663
664 rc = -EINVAL;
665 scontextp = (char *) scontext2;
666
667 /* Extract the user. */
668 p = scontextp;
669 while (*p && *p != ':')
670 p++;
671
672 if (*p == 0)
673 goto out_unlock;
674
675 *p++ = 0;
676
677 usrdatum = hashtab_search(policydb.p_users.table, scontextp);
678 if (!usrdatum)
679 goto out_unlock;
680
681 context.user = usrdatum->value;
682
683 /* Extract role. */
684 scontextp = p;
685 while (*p && *p != ':')
686 p++;
687
688 if (*p == 0)
689 goto out_unlock;
690
691 *p++ = 0;
692
693 role = hashtab_search(policydb.p_roles.table, scontextp);
694 if (!role)
695 goto out_unlock;
696 context.role = role->value;
697
698 /* Extract type. */
699 scontextp = p;
700 while (*p && *p != ':')
701 p++;
702 oldc = *p;
703 *p++ = 0;
704
705 typdatum = hashtab_search(policydb.p_types.table, scontextp);
706 if (!typdatum)
707 goto out_unlock;
708
709 context.type = typdatum->value;
710
711 rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
712 if (rc)
713 goto out_unlock;
714
715 if ((p - scontext2) < scontext_len) {
716 rc = -EINVAL;
717 goto out_unlock;
718 }
719
720 /* Check the validity of the new context. */
721 if (!policydb_context_isvalid(&policydb, &context)) {
722 rc = -EINVAL;
723 goto out_unlock;
724 }
725 /* Obtain the new sid. */
726 rc = sidtab_context_to_sid(&sidtab, &context, sid);
727 out_unlock:
728 POLICY_RDUNLOCK;
729 context_destroy(&context);
730 kfree(scontext2);
731 out:
732 return rc;
733 }
734
735 /**
736 * security_context_to_sid - Obtain a SID for a given security context.
737 * @scontext: security context
738 * @scontext_len: length in bytes
739 * @sid: security identifier, SID
740 *
741 * Obtains a SID associated with the security context that
742 * has the string representation specified by @scontext.
743 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
744 * memory is available, or 0 on success.
745 */
746 int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
747 {
748 return security_context_to_sid_core(scontext, scontext_len,
749 sid, SECSID_NULL);
750 }
751
752 /**
753 * security_context_to_sid_default - Obtain a SID for a given security context,
754 * falling back to specified default if needed.
755 *
756 * @scontext: security context
757 * @scontext_len: length in bytes
758 * @sid: security identifier, SID
759 * @def_sid: default SID to assign on errror
760 *
761 * Obtains a SID associated with the security context that
762 * has the string representation specified by @scontext.
763 * The default SID is passed to the MLS layer to be used to allow
764 * kernel labeling of the MLS field if the MLS field is not present
765 * (for upgrading to MLS without full relabel).
766 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
767 * memory is available, or 0 on success.
768 */
769 int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
770 {
771 return security_context_to_sid_core(scontext, scontext_len,
772 sid, def_sid);
773 }
774
775 static int compute_sid_handle_invalid_context(
776 struct context *scontext,
777 struct context *tcontext,
778 u16 tclass,
779 struct context *newcontext)
780 {
781 char *s = NULL, *t = NULL, *n = NULL;
782 u32 slen, tlen, nlen;
783
784 if (context_struct_to_string(scontext, &s, &slen) < 0)
785 goto out;
786 if (context_struct_to_string(tcontext, &t, &tlen) < 0)
787 goto out;
788 if (context_struct_to_string(newcontext, &n, &nlen) < 0)
789 goto out;
790 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
791 "security_compute_sid: invalid context %s"
792 " for scontext=%s"
793 " tcontext=%s"
794 " tclass=%s",
795 n, s, t, policydb.p_class_val_to_name[tclass-1]);
796 out:
797 kfree(s);
798 kfree(t);
799 kfree(n);
800 if (!selinux_enforcing)
801 return 0;
802 return -EACCES;
803 }
804
805 static int security_compute_sid(u32 ssid,
806 u32 tsid,
807 u16 tclass,
808 u32 specified,
809 u32 *out_sid)
810 {
811 struct context *scontext = NULL, *tcontext = NULL, newcontext;
812 struct role_trans *roletr = NULL;
813 struct avtab_key avkey;
814 struct avtab_datum *avdatum;
815 struct avtab_node *node;
816 int rc = 0;
817
818 if (!ss_initialized) {
819 switch (tclass) {
820 case SECCLASS_PROCESS:
821 *out_sid = ssid;
822 break;
823 default:
824 *out_sid = tsid;
825 break;
826 }
827 goto out;
828 }
829
830 POLICY_RDLOCK;
831
832 scontext = sidtab_search(&sidtab, ssid);
833 if (!scontext) {
834 printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n",
835 ssid);
836 rc = -EINVAL;
837 goto out_unlock;
838 }
839 tcontext = sidtab_search(&sidtab, tsid);
840 if (!tcontext) {
841 printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n",
842 tsid);
843 rc = -EINVAL;
844 goto out_unlock;
845 }
846
847 context_init(&newcontext);
848
849 /* Set the user identity. */
850 switch (specified) {
851 case AVTAB_TRANSITION:
852 case AVTAB_CHANGE:
853 /* Use the process user identity. */
854 newcontext.user = scontext->user;
855 break;
856 case AVTAB_MEMBER:
857 /* Use the related object owner. */
858 newcontext.user = tcontext->user;
859 break;
860 }
861
862 /* Set the role and type to default values. */
863 switch (tclass) {
864 case SECCLASS_PROCESS:
865 /* Use the current role and type of process. */
866 newcontext.role = scontext->role;
867 newcontext.type = scontext->type;
868 break;
869 default:
870 /* Use the well-defined object role. */
871 newcontext.role = OBJECT_R_VAL;
872 /* Use the type of the related object. */
873 newcontext.type = tcontext->type;
874 }
875
876 /* Look for a type transition/member/change rule. */
877 avkey.source_type = scontext->type;
878 avkey.target_type = tcontext->type;
879 avkey.target_class = tclass;
880 avkey.specified = specified;
881 avdatum = avtab_search(&policydb.te_avtab, &avkey);
882
883 /* If no permanent rule, also check for enabled conditional rules */
884 if(!avdatum) {
885 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
886 for (; node != NULL; node = avtab_search_node_next(node, specified)) {
887 if (node->key.specified & AVTAB_ENABLED) {
888 avdatum = &node->datum;
889 break;
890 }
891 }
892 }
893
894 if (avdatum) {
895 /* Use the type from the type transition/member/change rule. */
896 newcontext.type = avdatum->data;
897 }
898
899 /* Check for class-specific changes. */
900 switch (tclass) {
901 case SECCLASS_PROCESS:
902 if (specified & AVTAB_TRANSITION) {
903 /* Look for a role transition rule. */
904 for (roletr = policydb.role_tr; roletr;
905 roletr = roletr->next) {
906 if (roletr->role == scontext->role &&
907 roletr->type == tcontext->type) {
908 /* Use the role transition rule. */
909 newcontext.role = roletr->new_role;
910 break;
911 }
912 }
913 }
914 break;
915 default:
916 break;
917 }
918
919 /* Set the MLS attributes.
920 This is done last because it may allocate memory. */
921 rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
922 if (rc)
923 goto out_unlock;
924
925 /* Check the validity of the context. */
926 if (!policydb_context_isvalid(&policydb, &newcontext)) {
927 rc = compute_sid_handle_invalid_context(scontext,
928 tcontext,
929 tclass,
930 &newcontext);
931 if (rc)
932 goto out_unlock;
933 }
934 /* Obtain the sid for the context. */
935 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
936 out_unlock:
937 POLICY_RDUNLOCK;
938 context_destroy(&newcontext);
939 out:
940 return rc;
941 }
942
943 /**
944 * security_transition_sid - Compute the SID for a new subject/object.
945 * @ssid: source security identifier
946 * @tsid: target security identifier
947 * @tclass: target security class
948 * @out_sid: security identifier for new subject/object
949 *
950 * Compute a SID to use for labeling a new subject or object in the
951 * class @tclass based on a SID pair (@ssid, @tsid).
952 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
953 * if insufficient memory is available, or %0 if the new SID was
954 * computed successfully.
955 */
956 int security_transition_sid(u32 ssid,
957 u32 tsid,
958 u16 tclass,
959 u32 *out_sid)
960 {
961 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
962 }
963
964 /**
965 * security_member_sid - Compute the SID for member selection.
966 * @ssid: source security identifier
967 * @tsid: target security identifier
968 * @tclass: target security class
969 * @out_sid: security identifier for selected member
970 *
971 * Compute a SID to use when selecting a member of a polyinstantiated
972 * object of class @tclass based on a SID pair (@ssid, @tsid).
973 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
974 * if insufficient memory is available, or %0 if the SID was
975 * computed successfully.
976 */
977 int security_member_sid(u32 ssid,
978 u32 tsid,
979 u16 tclass,
980 u32 *out_sid)
981 {
982 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
983 }
984
985 /**
986 * security_change_sid - Compute the SID for object relabeling.
987 * @ssid: source security identifier
988 * @tsid: target security identifier
989 * @tclass: target security class
990 * @out_sid: security identifier for selected member
991 *
992 * Compute a SID to use for relabeling an object of class @tclass
993 * based on a SID pair (@ssid, @tsid).
994 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
995 * if insufficient memory is available, or %0 if the SID was
996 * computed successfully.
997 */
998 int security_change_sid(u32 ssid,
999 u32 tsid,
1000 u16 tclass,
1001 u32 *out_sid)
1002 {
1003 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
1004 }
1005
1006 /*
1007 * Verify that each permission that is defined under the
1008 * existing policy is still defined with the same value
1009 * in the new policy.
1010 */
1011 static int validate_perm(void *key, void *datum, void *p)
1012 {
1013 struct hashtab *h;
1014 struct perm_datum *perdatum, *perdatum2;
1015 int rc = 0;
1016
1017
1018 h = p;
1019 perdatum = datum;
1020
1021 perdatum2 = hashtab_search(h, key);
1022 if (!perdatum2) {
1023 printk(KERN_ERR "security: permission %s disappeared",
1024 (char *)key);
1025 rc = -ENOENT;
1026 goto out;
1027 }
1028 if (perdatum->value != perdatum2->value) {
1029 printk(KERN_ERR "security: the value of permission %s changed",
1030 (char *)key);
1031 rc = -EINVAL;
1032 }
1033 out:
1034 return rc;
1035 }
1036
1037 /*
1038 * Verify that each class that is defined under the
1039 * existing policy is still defined with the same
1040 * attributes in the new policy.
1041 */
1042 static int validate_class(void *key, void *datum, void *p)
1043 {
1044 struct policydb *newp;
1045 struct class_datum *cladatum, *cladatum2;
1046 int rc;
1047
1048 newp = p;
1049 cladatum = datum;
1050
1051 cladatum2 = hashtab_search(newp->p_classes.table, key);
1052 if (!cladatum2) {
1053 printk(KERN_ERR "security: class %s disappeared\n",
1054 (char *)key);
1055 rc = -ENOENT;
1056 goto out;
1057 }
1058 if (cladatum->value != cladatum2->value) {
1059 printk(KERN_ERR "security: the value of class %s changed\n",
1060 (char *)key);
1061 rc = -EINVAL;
1062 goto out;
1063 }
1064 if ((cladatum->comdatum && !cladatum2->comdatum) ||
1065 (!cladatum->comdatum && cladatum2->comdatum)) {
1066 printk(KERN_ERR "security: the inherits clause for the access "
1067 "vector definition for class %s changed\n", (char *)key);
1068 rc = -EINVAL;
1069 goto out;
1070 }
1071 if (cladatum->comdatum) {
1072 rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm,
1073 cladatum2->comdatum->permissions.table);
1074 if (rc) {
1075 printk(" in the access vector definition for class "
1076 "%s\n", (char *)key);
1077 goto out;
1078 }
1079 }
1080 rc = hashtab_map(cladatum->permissions.table, validate_perm,
1081 cladatum2->permissions.table);
1082 if (rc)
1083 printk(" in access vector definition for class %s\n",
1084 (char *)key);
1085 out:
1086 return rc;
1087 }
1088
1089 /* Clone the SID into the new SID table. */
1090 static int clone_sid(u32 sid,
1091 struct context *context,
1092 void *arg)
1093 {
1094 struct sidtab *s = arg;
1095
1096 return sidtab_insert(s, sid, context);
1097 }
1098
1099 static inline int convert_context_handle_invalid_context(struct context *context)
1100 {
1101 int rc = 0;
1102
1103 if (selinux_enforcing) {
1104 rc = -EINVAL;
1105 } else {
1106 char *s;
1107 u32 len;
1108
1109 context_struct_to_string(context, &s, &len);
1110 printk(KERN_ERR "security: context %s is invalid\n", s);
1111 kfree(s);
1112 }
1113 return rc;
1114 }
1115
1116 struct convert_context_args {
1117 struct policydb *oldp;
1118 struct policydb *newp;
1119 };
1120
1121 /*
1122 * Convert the values in the security context
1123 * structure `c' from the values specified
1124 * in the policy `p->oldp' to the values specified
1125 * in the policy `p->newp'. Verify that the
1126 * context is valid under the new policy.
1127 */
1128 static int convert_context(u32 key,
1129 struct context *c,
1130 void *p)
1131 {
1132 struct convert_context_args *args;
1133 struct context oldc;
1134 struct role_datum *role;
1135 struct type_datum *typdatum;
1136 struct user_datum *usrdatum;
1137 char *s;
1138 u32 len;
1139 int rc;
1140
1141 args = p;
1142
1143 rc = context_cpy(&oldc, c);
1144 if (rc)
1145 goto out;
1146
1147 rc = -EINVAL;
1148
1149 /* Convert the user. */
1150 usrdatum = hashtab_search(args->newp->p_users.table,
1151 args->oldp->p_user_val_to_name[c->user - 1]);
1152 if (!usrdatum) {
1153 goto bad;
1154 }
1155 c->user = usrdatum->value;
1156
1157 /* Convert the role. */
1158 role = hashtab_search(args->newp->p_roles.table,
1159 args->oldp->p_role_val_to_name[c->role - 1]);
1160 if (!role) {
1161 goto bad;
1162 }
1163 c->role = role->value;
1164
1165 /* Convert the type. */
1166 typdatum = hashtab_search(args->newp->p_types.table,
1167 args->oldp->p_type_val_to_name[c->type - 1]);
1168 if (!typdatum) {
1169 goto bad;
1170 }
1171 c->type = typdatum->value;
1172
1173 rc = mls_convert_context(args->oldp, args->newp, c);
1174 if (rc)
1175 goto bad;
1176
1177 /* Check the validity of the new context. */
1178 if (!policydb_context_isvalid(args->newp, c)) {
1179 rc = convert_context_handle_invalid_context(&oldc);
1180 if (rc)
1181 goto bad;
1182 }
1183
1184 context_destroy(&oldc);
1185 out:
1186 return rc;
1187 bad:
1188 context_struct_to_string(&oldc, &s, &len);
1189 context_destroy(&oldc);
1190 printk(KERN_ERR "security: invalidating context %s\n", s);
1191 kfree(s);
1192 goto out;
1193 }
1194
1195 extern void selinux_complete_init(void);
1196
1197 /**
1198 * security_load_policy - Load a security policy configuration.
1199 * @data: binary policy data
1200 * @len: length of data in bytes
1201 *
1202 * Load a new set of security policy configuration data,
1203 * validate it and convert the SID table as necessary.
1204 * This function will flush the access vector cache after
1205 * loading the new policy.
1206 */
1207 int security_load_policy(void *data, size_t len)
1208 {
1209 struct policydb oldpolicydb, newpolicydb;
1210 struct sidtab oldsidtab, newsidtab;
1211 struct convert_context_args args;
1212 u32 seqno;
1213 int rc = 0;
1214 struct policy_file file = { data, len }, *fp = &file;
1215
1216 LOAD_LOCK;
1217
1218 if (!ss_initialized) {
1219 avtab_cache_init();
1220 if (policydb_read(&policydb, fp)) {
1221 LOAD_UNLOCK;
1222 avtab_cache_destroy();
1223 return -EINVAL;
1224 }
1225 if (policydb_load_isids(&policydb, &sidtab)) {
1226 LOAD_UNLOCK;
1227 policydb_destroy(&policydb);
1228 avtab_cache_destroy();
1229 return -EINVAL;
1230 }
1231 policydb_loaded_version = policydb.policyvers;
1232 ss_initialized = 1;
1233 seqno = ++latest_granting;
1234 LOAD_UNLOCK;
1235 selinux_complete_init();
1236 avc_ss_reset(seqno);
1237 selnl_notify_policyload(seqno);
1238 return 0;
1239 }
1240
1241 #if 0
1242 sidtab_hash_eval(&sidtab, "sids");
1243 #endif
1244
1245 if (policydb_read(&newpolicydb, fp)) {
1246 LOAD_UNLOCK;
1247 return -EINVAL;
1248 }
1249
1250 sidtab_init(&newsidtab);
1251
1252 /* Verify that the existing classes did not change. */
1253 if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) {
1254 printk(KERN_ERR "security: the definition of an existing "
1255 "class changed\n");
1256 rc = -EINVAL;
1257 goto err;
1258 }
1259
1260 /* Clone the SID table. */
1261 sidtab_shutdown(&sidtab);
1262 if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
1263 rc = -ENOMEM;
1264 goto err;
1265 }
1266
1267 /* Convert the internal representations of contexts
1268 in the new SID table and remove invalid SIDs. */
1269 args.oldp = &policydb;
1270 args.newp = &newpolicydb;
1271 sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
1272
1273 /* Save the old policydb and SID table to free later. */
1274 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1275 sidtab_set(&oldsidtab, &sidtab);
1276
1277 /* Install the new policydb and SID table. */
1278 POLICY_WRLOCK;
1279 memcpy(&policydb, &newpolicydb, sizeof policydb);
1280 sidtab_set(&sidtab, &newsidtab);
1281 seqno = ++latest_granting;
1282 policydb_loaded_version = policydb.policyvers;
1283 POLICY_WRUNLOCK;
1284 LOAD_UNLOCK;
1285
1286 /* Free the old policydb and SID table. */
1287 policydb_destroy(&oldpolicydb);
1288 sidtab_destroy(&oldsidtab);
1289
1290 avc_ss_reset(seqno);
1291 selnl_notify_policyload(seqno);
1292
1293 return 0;
1294
1295 err:
1296 LOAD_UNLOCK;
1297 sidtab_destroy(&newsidtab);
1298 policydb_destroy(&newpolicydb);
1299 return rc;
1300
1301 }
1302
1303 /**
1304 * security_port_sid - Obtain the SID for a port.
1305 * @domain: communication domain aka address family
1306 * @type: socket type
1307 * @protocol: protocol number
1308 * @port: port number
1309 * @out_sid: security identifier
1310 */
1311 int security_port_sid(u16 domain,
1312 u16 type,
1313 u8 protocol,
1314 u16 port,
1315 u32 *out_sid)
1316 {
1317 struct ocontext *c;
1318 int rc = 0;
1319
1320 POLICY_RDLOCK;
1321
1322 c = policydb.ocontexts[OCON_PORT];
1323 while (c) {
1324 if (c->u.port.protocol == protocol &&
1325 c->u.port.low_port <= port &&
1326 c->u.port.high_port >= port)
1327 break;
1328 c = c->next;
1329 }
1330
1331 if (c) {
1332 if (!c->sid[0]) {
1333 rc = sidtab_context_to_sid(&sidtab,
1334 &c->context[0],
1335 &c->sid[0]);
1336 if (rc)
1337 goto out;
1338 }
1339 *out_sid = c->sid[0];
1340 } else {
1341 *out_sid = SECINITSID_PORT;
1342 }
1343
1344 out:
1345 POLICY_RDUNLOCK;
1346 return rc;
1347 }
1348
1349 /**
1350 * security_netif_sid - Obtain the SID for a network interface.
1351 * @name: interface name
1352 * @if_sid: interface SID
1353 * @msg_sid: default SID for received packets
1354 */
1355 int security_netif_sid(char *name,
1356 u32 *if_sid,
1357 u32 *msg_sid)
1358 {
1359 int rc = 0;
1360 struct ocontext *c;
1361
1362 POLICY_RDLOCK;
1363
1364 c = policydb.ocontexts[OCON_NETIF];
1365 while (c) {
1366 if (strcmp(name, c->u.name) == 0)
1367 break;
1368 c = c->next;
1369 }
1370
1371 if (c) {
1372 if (!c->sid[0] || !c->sid[1]) {
1373 rc = sidtab_context_to_sid(&sidtab,
1374 &c->context[0],
1375 &c->sid[0]);
1376 if (rc)
1377 goto out;
1378 rc = sidtab_context_to_sid(&sidtab,
1379 &c->context[1],
1380 &c->sid[1]);
1381 if (rc)
1382 goto out;
1383 }
1384 *if_sid = c->sid[0];
1385 *msg_sid = c->sid[1];
1386 } else {
1387 *if_sid = SECINITSID_NETIF;
1388 *msg_sid = SECINITSID_NETMSG;
1389 }
1390
1391 out:
1392 POLICY_RDUNLOCK;
1393 return rc;
1394 }
1395
1396 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1397 {
1398 int i, fail = 0;
1399
1400 for(i = 0; i < 4; i++)
1401 if(addr[i] != (input[i] & mask[i])) {
1402 fail = 1;
1403 break;
1404 }
1405
1406 return !fail;
1407 }
1408
1409 /**
1410 * security_node_sid - Obtain the SID for a node (host).
1411 * @domain: communication domain aka address family
1412 * @addrp: address
1413 * @addrlen: address length in bytes
1414 * @out_sid: security identifier
1415 */
1416 int security_node_sid(u16 domain,
1417 void *addrp,
1418 u32 addrlen,
1419 u32 *out_sid)
1420 {
1421 int rc = 0;
1422 struct ocontext *c;
1423
1424 POLICY_RDLOCK;
1425
1426 switch (domain) {
1427 case AF_INET: {
1428 u32 addr;
1429
1430 if (addrlen != sizeof(u32)) {
1431 rc = -EINVAL;
1432 goto out;
1433 }
1434
1435 addr = *((u32 *)addrp);
1436
1437 c = policydb.ocontexts[OCON_NODE];
1438 while (c) {
1439 if (c->u.node.addr == (addr & c->u.node.mask))
1440 break;
1441 c = c->next;
1442 }
1443 break;
1444 }
1445
1446 case AF_INET6:
1447 if (addrlen != sizeof(u64) * 2) {
1448 rc = -EINVAL;
1449 goto out;
1450 }
1451 c = policydb.ocontexts[OCON_NODE6];
1452 while (c) {
1453 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
1454 c->u.node6.mask))
1455 break;
1456 c = c->next;
1457 }
1458 break;
1459
1460 default:
1461 *out_sid = SECINITSID_NODE;
1462 goto out;
1463 }
1464
1465 if (c) {
1466 if (!c->sid[0]) {
1467 rc = sidtab_context_to_sid(&sidtab,
1468 &c->context[0],
1469 &c->sid[0]);
1470 if (rc)
1471 goto out;
1472 }
1473 *out_sid = c->sid[0];
1474 } else {
1475 *out_sid = SECINITSID_NODE;
1476 }
1477
1478 out:
1479 POLICY_RDUNLOCK;
1480 return rc;
1481 }
1482
1483 #define SIDS_NEL 25
1484
1485 /**
1486 * security_get_user_sids - Obtain reachable SIDs for a user.
1487 * @fromsid: starting SID
1488 * @username: username
1489 * @sids: array of reachable SIDs for user
1490 * @nel: number of elements in @sids
1491 *
1492 * Generate the set of SIDs for legal security contexts
1493 * for a given user that can be reached by @fromsid.
1494 * Set *@sids to point to a dynamically allocated
1495 * array containing the set of SIDs. Set *@nel to the
1496 * number of elements in the array.
1497 */
1498
1499 int security_get_user_sids(u32 fromsid,
1500 char *username,
1501 u32 **sids,
1502 u32 *nel)
1503 {
1504 struct context *fromcon, usercon;
1505 u32 *mysids, *mysids2, sid;
1506 u32 mynel = 0, maxnel = SIDS_NEL;
1507 struct user_datum *user;
1508 struct role_datum *role;
1509 struct av_decision avd;
1510 struct ebitmap_node *rnode, *tnode;
1511 int rc = 0, i, j;
1512
1513 if (!ss_initialized) {
1514 *sids = NULL;
1515 *nel = 0;
1516 goto out;
1517 }
1518
1519 POLICY_RDLOCK;
1520
1521 fromcon = sidtab_search(&sidtab, fromsid);
1522 if (!fromcon) {
1523 rc = -EINVAL;
1524 goto out_unlock;
1525 }
1526
1527 user = hashtab_search(policydb.p_users.table, username);
1528 if (!user) {
1529 rc = -EINVAL;
1530 goto out_unlock;
1531 }
1532 usercon.user = user->value;
1533
1534 mysids = kmalloc(maxnel*sizeof(*mysids), GFP_ATOMIC);
1535 if (!mysids) {
1536 rc = -ENOMEM;
1537 goto out_unlock;
1538 }
1539 memset(mysids, 0, maxnel*sizeof(*mysids));
1540
1541 ebitmap_for_each_bit(&user->roles, rnode, i) {
1542 if (!ebitmap_node_get_bit(rnode, i))
1543 continue;
1544 role = policydb.role_val_to_struct[i];
1545 usercon.role = i+1;
1546 ebitmap_for_each_bit(&role->types, tnode, j) {
1547 if (!ebitmap_node_get_bit(tnode, j))
1548 continue;
1549 usercon.type = j+1;
1550
1551 if (mls_setup_user_range(fromcon, user, &usercon))
1552 continue;
1553
1554 rc = context_struct_compute_av(fromcon, &usercon,
1555 SECCLASS_PROCESS,
1556 PROCESS__TRANSITION,
1557 &avd);
1558 if (rc || !(avd.allowed & PROCESS__TRANSITION))
1559 continue;
1560 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
1561 if (rc) {
1562 kfree(mysids);
1563 goto out_unlock;
1564 }
1565 if (mynel < maxnel) {
1566 mysids[mynel++] = sid;
1567 } else {
1568 maxnel += SIDS_NEL;
1569 mysids2 = kmalloc(maxnel*sizeof(*mysids2), GFP_ATOMIC);
1570 if (!mysids2) {
1571 rc = -ENOMEM;
1572 kfree(mysids);
1573 goto out_unlock;
1574 }
1575 memset(mysids2, 0, maxnel*sizeof(*mysids2));
1576 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
1577 kfree(mysids);
1578 mysids = mysids2;
1579 mysids[mynel++] = sid;
1580 }
1581 }
1582 }
1583
1584 *sids = mysids;
1585 *nel = mynel;
1586
1587 out_unlock:
1588 POLICY_RDUNLOCK;
1589 out:
1590 return rc;
1591 }
1592
1593 /**
1594 * security_genfs_sid - Obtain a SID for a file in a filesystem
1595 * @fstype: filesystem type
1596 * @path: path from root of mount
1597 * @sclass: file security class
1598 * @sid: SID for path
1599 *
1600 * Obtain a SID to use for a file in a filesystem that
1601 * cannot support xattr or use a fixed labeling behavior like
1602 * transition SIDs or task SIDs.
1603 */
1604 int security_genfs_sid(const char *fstype,
1605 char *path,
1606 u16 sclass,
1607 u32 *sid)
1608 {
1609 int len;
1610 struct genfs *genfs;
1611 struct ocontext *c;
1612 int rc = 0, cmp = 0;
1613
1614 POLICY_RDLOCK;
1615
1616 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
1617 cmp = strcmp(fstype, genfs->fstype);
1618 if (cmp <= 0)
1619 break;
1620 }
1621
1622 if (!genfs || cmp) {
1623 *sid = SECINITSID_UNLABELED;
1624 rc = -ENOENT;
1625 goto out;
1626 }
1627
1628 for (c = genfs->head; c; c = c->next) {
1629 len = strlen(c->u.name);
1630 if ((!c->v.sclass || sclass == c->v.sclass) &&
1631 (strncmp(c->u.name, path, len) == 0))
1632 break;
1633 }
1634
1635 if (!c) {
1636 *sid = SECINITSID_UNLABELED;
1637 rc = -ENOENT;
1638 goto out;
1639 }
1640
1641 if (!c->sid[0]) {
1642 rc = sidtab_context_to_sid(&sidtab,
1643 &c->context[0],
1644 &c->sid[0]);
1645 if (rc)
1646 goto out;
1647 }
1648
1649 *sid = c->sid[0];
1650 out:
1651 POLICY_RDUNLOCK;
1652 return rc;
1653 }
1654
1655 /**
1656 * security_fs_use - Determine how to handle labeling for a filesystem.
1657 * @fstype: filesystem type
1658 * @behavior: labeling behavior
1659 * @sid: SID for filesystem (superblock)
1660 */
1661 int security_fs_use(
1662 const char *fstype,
1663 unsigned int *behavior,
1664 u32 *sid)
1665 {
1666 int rc = 0;
1667 struct ocontext *c;
1668
1669 POLICY_RDLOCK;
1670
1671 c = policydb.ocontexts[OCON_FSUSE];
1672 while (c) {
1673 if (strcmp(fstype, c->u.name) == 0)
1674 break;
1675 c = c->next;
1676 }
1677
1678 if (c) {
1679 *behavior = c->v.behavior;
1680 if (!c->sid[0]) {
1681 rc = sidtab_context_to_sid(&sidtab,
1682 &c->context[0],
1683 &c->sid[0]);
1684 if (rc)
1685 goto out;
1686 }
1687 *sid = c->sid[0];
1688 } else {
1689 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
1690 if (rc) {
1691 *behavior = SECURITY_FS_USE_NONE;
1692 rc = 0;
1693 } else {
1694 *behavior = SECURITY_FS_USE_GENFS;
1695 }
1696 }
1697
1698 out:
1699 POLICY_RDUNLOCK;
1700 return rc;
1701 }
1702
1703 int security_get_bools(int *len, char ***names, int **values)
1704 {
1705 int i, rc = -ENOMEM;
1706
1707 POLICY_RDLOCK;
1708 *names = NULL;
1709 *values = NULL;
1710
1711 *len = policydb.p_bools.nprim;
1712 if (!*len) {
1713 rc = 0;
1714 goto out;
1715 }
1716
1717 *names = (char**)kmalloc(sizeof(char*) * *len, GFP_ATOMIC);
1718 if (!*names)
1719 goto err;
1720 memset(*names, 0, sizeof(char*) * *len);
1721
1722 *values = (int*)kmalloc(sizeof(int) * *len, GFP_ATOMIC);
1723 if (!*values)
1724 goto err;
1725
1726 for (i = 0; i < *len; i++) {
1727 size_t name_len;
1728 (*values)[i] = policydb.bool_val_to_struct[i]->state;
1729 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
1730 (*names)[i] = (char*)kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
1731 if (!(*names)[i])
1732 goto err;
1733 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
1734 (*names)[i][name_len - 1] = 0;
1735 }
1736 rc = 0;
1737 out:
1738 POLICY_RDUNLOCK;
1739 return rc;
1740 err:
1741 if (*names) {
1742 for (i = 0; i < *len; i++)
1743 kfree((*names)[i]);
1744 }
1745 kfree(*values);
1746 goto out;
1747 }
1748
1749
1750 int security_set_bools(int len, int *values)
1751 {
1752 int i, rc = 0;
1753 int lenp, seqno = 0;
1754 struct cond_node *cur;
1755
1756 POLICY_WRLOCK;
1757
1758 lenp = policydb.p_bools.nprim;
1759 if (len != lenp) {
1760 rc = -EFAULT;
1761 goto out;
1762 }
1763
1764 printk(KERN_INFO "security: committed booleans { ");
1765 for (i = 0; i < len; i++) {
1766 if (values[i]) {
1767 policydb.bool_val_to_struct[i]->state = 1;
1768 } else {
1769 policydb.bool_val_to_struct[i]->state = 0;
1770 }
1771 if (i != 0)
1772 printk(", ");
1773 printk("%s:%d", policydb.p_bool_val_to_name[i],
1774 policydb.bool_val_to_struct[i]->state);
1775 }
1776 printk(" }\n");
1777
1778 for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
1779 rc = evaluate_cond_node(&policydb, cur);
1780 if (rc)
1781 goto out;
1782 }
1783
1784 seqno = ++latest_granting;
1785
1786 out:
1787 POLICY_WRUNLOCK;
1788 if (!rc) {
1789 avc_ss_reset(seqno);
1790 selnl_notify_policyload(seqno);
1791 }
1792 return rc;
1793 }
1794
1795 int security_get_bool_value(int bool)
1796 {
1797 int rc = 0;
1798 int len;
1799
1800 POLICY_RDLOCK;
1801
1802 len = policydb.p_bools.nprim;
1803 if (bool >= len) {
1804 rc = -EFAULT;
1805 goto out;
1806 }
1807
1808 rc = policydb.bool_val_to_struct[bool]->state;
1809 out:
1810 POLICY_RDUNLOCK;
1811 return rc;
1812 }
kernel source for telekom puls (alcatel/mediatek)