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-rw-r--r--security/selinux/ss/services.c1777
1 files changed, 1777 insertions, 0 deletions
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
new file mode 100644
index 000000000000..5a820cf88c9c
--- /dev/null
+++ b/security/selinux/ss/services.c
@@ -0,0 +1,1777 @@
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
42extern void selnl_notify_policyload(u32 seqno);
43unsigned int policydb_loaded_version;
44
45static 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
51static DECLARE_MUTEX(load_sem);
52#define LOAD_LOCK down(&load_sem)
53#define LOAD_UNLOCK up(&load_sem)
54
55static struct sidtab sidtab;
56struct policydb policydb;
57int 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 */
65static u32 latest_granting = 0;
66
67/* Forward declaration. */
68static 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 */
82static 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;
171mls_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 */
260static 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_datum *avdatum;
270 struct class_datum *tclass_datum;
271
272 /*
273 * Remap extended Netlink classes for old policy versions.
274 * Do this here rather than socket_type_to_security_class()
275 * in case a newer policy version is loaded, allowing sockets
276 * to remain in the correct class.
277 */
278 if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
279 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
280 tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
281 tclass = SECCLASS_NETLINK_SOCKET;
282
283 if (!tclass || tclass > policydb.p_classes.nprim) {
284 printk(KERN_ERR "security_compute_av: unrecognized class %d\n",
285 tclass);
286 return -EINVAL;
287 }
288 tclass_datum = policydb.class_val_to_struct[tclass - 1];
289
290 /*
291 * Initialize the access vectors to the default values.
292 */
293 avd->allowed = 0;
294 avd->decided = 0xffffffff;
295 avd->auditallow = 0;
296 avd->auditdeny = 0xffffffff;
297 avd->seqno = latest_granting;
298
299 /*
300 * If a specific type enforcement rule was defined for
301 * this permission check, then use it.
302 */
303 avkey.source_type = scontext->type;
304 avkey.target_type = tcontext->type;
305 avkey.target_class = tclass;
306 avdatum = avtab_search(&policydb.te_avtab, &avkey, AVTAB_AV);
307 if (avdatum) {
308 if (avdatum->specified & AVTAB_ALLOWED)
309 avd->allowed = avtab_allowed(avdatum);
310 if (avdatum->specified & AVTAB_AUDITDENY)
311 avd->auditdeny = avtab_auditdeny(avdatum);
312 if (avdatum->specified & AVTAB_AUDITALLOW)
313 avd->auditallow = avtab_auditallow(avdatum);
314 }
315
316 /* Check conditional av table for additional permissions */
317 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
318
319 /*
320 * Remove any permissions prohibited by a constraint (this includes
321 * the MLS policy).
322 */
323 constraint = tclass_datum->constraints;
324 while (constraint) {
325 if ((constraint->permissions & (avd->allowed)) &&
326 !constraint_expr_eval(scontext, tcontext, NULL,
327 constraint->expr)) {
328 avd->allowed = (avd->allowed) & ~(constraint->permissions);
329 }
330 constraint = constraint->next;
331 }
332
333 /*
334 * If checking process transition permission and the
335 * role is changing, then check the (current_role, new_role)
336 * pair.
337 */
338 if (tclass == SECCLASS_PROCESS &&
339 (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
340 scontext->role != tcontext->role) {
341 for (ra = policydb.role_allow; ra; ra = ra->next) {
342 if (scontext->role == ra->role &&
343 tcontext->role == ra->new_role)
344 break;
345 }
346 if (!ra)
347 avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
348 PROCESS__DYNTRANSITION);
349 }
350
351 return 0;
352}
353
354static int security_validtrans_handle_fail(struct context *ocontext,
355 struct context *ncontext,
356 struct context *tcontext,
357 u16 tclass)
358{
359 char *o = NULL, *n = NULL, *t = NULL;
360 u32 olen, nlen, tlen;
361
362 if (context_struct_to_string(ocontext, &o, &olen) < 0)
363 goto out;
364 if (context_struct_to_string(ncontext, &n, &nlen) < 0)
365 goto out;
366 if (context_struct_to_string(tcontext, &t, &tlen) < 0)
367 goto out;
368 audit_log(current->audit_context,
369 "security_validate_transition: denied for"
370 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
371 o, n, t, policydb.p_class_val_to_name[tclass-1]);
372out:
373 kfree(o);
374 kfree(n);
375 kfree(t);
376
377 if (!selinux_enforcing)
378 return 0;
379 return -EPERM;
380}
381
382int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
383 u16 tclass)
384{
385 struct context *ocontext;
386 struct context *ncontext;
387 struct context *tcontext;
388 struct class_datum *tclass_datum;
389 struct constraint_node *constraint;
390 int rc = 0;
391
392 if (!ss_initialized)
393 return 0;
394
395 POLICY_RDLOCK;
396
397 /*
398 * Remap extended Netlink classes for old policy versions.
399 * Do this here rather than socket_type_to_security_class()
400 * in case a newer policy version is loaded, allowing sockets
401 * to remain in the correct class.
402 */
403 if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
404 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
405 tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
406 tclass = SECCLASS_NETLINK_SOCKET;
407
408 if (!tclass || tclass > policydb.p_classes.nprim) {
409 printk(KERN_ERR "security_validate_transition: "
410 "unrecognized class %d\n", tclass);
411 rc = -EINVAL;
412 goto out;
413 }
414 tclass_datum = policydb.class_val_to_struct[tclass - 1];
415
416 ocontext = sidtab_search(&sidtab, oldsid);
417 if (!ocontext) {
418 printk(KERN_ERR "security_validate_transition: "
419 " unrecognized SID %d\n", oldsid);
420 rc = -EINVAL;
421 goto out;
422 }
423
424 ncontext = sidtab_search(&sidtab, newsid);
425 if (!ncontext) {
426 printk(KERN_ERR "security_validate_transition: "
427 " unrecognized SID %d\n", newsid);
428 rc = -EINVAL;
429 goto out;
430 }
431
432 tcontext = sidtab_search(&sidtab, tasksid);
433 if (!tcontext) {
434 printk(KERN_ERR "security_validate_transition: "
435 " unrecognized SID %d\n", tasksid);
436 rc = -EINVAL;
437 goto out;
438 }
439
440 constraint = tclass_datum->validatetrans;
441 while (constraint) {
442 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
443 constraint->expr)) {
444 rc = security_validtrans_handle_fail(ocontext, ncontext,
445 tcontext, tclass);
446 goto out;
447 }
448 constraint = constraint->next;
449 }
450
451out:
452 POLICY_RDUNLOCK;
453 return rc;
454}
455
456/**
457 * security_compute_av - Compute access vector decisions.
458 * @ssid: source security identifier
459 * @tsid: target security identifier
460 * @tclass: target security class
461 * @requested: requested permissions
462 * @avd: access vector decisions
463 *
464 * Compute a set of access vector decisions based on the
465 * SID pair (@ssid, @tsid) for the permissions in @tclass.
466 * Return -%EINVAL if any of the parameters are invalid or %0
467 * if the access vector decisions were computed successfully.
468 */
469int security_compute_av(u32 ssid,
470 u32 tsid,
471 u16 tclass,
472 u32 requested,
473 struct av_decision *avd)
474{
475 struct context *scontext = NULL, *tcontext = NULL;
476 int rc = 0;
477
478 if (!ss_initialized) {
479 avd->allowed = requested;
480 avd->decided = requested;
481 avd->auditallow = 0;
482 avd->auditdeny = 0xffffffff;
483 avd->seqno = latest_granting;
484 return 0;
485 }
486
487 POLICY_RDLOCK;
488
489 scontext = sidtab_search(&sidtab, ssid);
490 if (!scontext) {
491 printk(KERN_ERR "security_compute_av: unrecognized SID %d\n",
492 ssid);
493 rc = -EINVAL;
494 goto out;
495 }
496 tcontext = sidtab_search(&sidtab, tsid);
497 if (!tcontext) {
498 printk(KERN_ERR "security_compute_av: unrecognized SID %d\n",
499 tsid);
500 rc = -EINVAL;
501 goto out;
502 }
503
504 rc = context_struct_compute_av(scontext, tcontext, tclass,
505 requested, avd);
506out:
507 POLICY_RDUNLOCK;
508 return rc;
509}
510
511/*
512 * Write the security context string representation of
513 * the context structure `context' into a dynamically
514 * allocated string of the correct size. Set `*scontext'
515 * to point to this string and set `*scontext_len' to
516 * the length of the string.
517 */
518static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
519{
520 char *scontextp;
521
522 *scontext = NULL;
523 *scontext_len = 0;
524
525 /* Compute the size of the context. */
526 *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
527 *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
528 *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
529 *scontext_len += mls_compute_context_len(context);
530
531 /* Allocate space for the context; caller must free this space. */
532 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
533 if (!scontextp) {
534 return -ENOMEM;
535 }
536 *scontext = scontextp;
537
538 /*
539 * Copy the user name, role name and type name into the context.
540 */
541 sprintf(scontextp, "%s:%s:%s",
542 policydb.p_user_val_to_name[context->user - 1],
543 policydb.p_role_val_to_name[context->role - 1],
544 policydb.p_type_val_to_name[context->type - 1]);
545 scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
546 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
547 1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
548
549 mls_sid_to_context(context, &scontextp);
550
551 *scontextp = 0;
552
553 return 0;
554}
555
556#include "initial_sid_to_string.h"
557
558/**
559 * security_sid_to_context - Obtain a context for a given SID.
560 * @sid: security identifier, SID
561 * @scontext: security context
562 * @scontext_len: length in bytes
563 *
564 * Write the string representation of the context associated with @sid
565 * into a dynamically allocated string of the correct size. Set @scontext
566 * to point to this string and set @scontext_len to the length of the string.
567 */
568int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
569{
570 struct context *context;
571 int rc = 0;
572
573 if (!ss_initialized) {
574 if (sid <= SECINITSID_NUM) {
575 char *scontextp;
576
577 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
578 scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
579 strcpy(scontextp, initial_sid_to_string[sid]);
580 *scontext = scontextp;
581 goto out;
582 }
583 printk(KERN_ERR "security_sid_to_context: called before initial "
584 "load_policy on unknown SID %d\n", sid);
585 rc = -EINVAL;
586 goto out;
587 }
588 POLICY_RDLOCK;
589 context = sidtab_search(&sidtab, sid);
590 if (!context) {
591 printk(KERN_ERR "security_sid_to_context: unrecognized SID "
592 "%d\n", sid);
593 rc = -EINVAL;
594 goto out_unlock;
595 }
596 rc = context_struct_to_string(context, scontext, scontext_len);
597out_unlock:
598 POLICY_RDUNLOCK;
599out:
600 return rc;
601
602}
603
604/**
605 * security_context_to_sid - Obtain a SID for a given security context.
606 * @scontext: security context
607 * @scontext_len: length in bytes
608 * @sid: security identifier, SID
609 *
610 * Obtains a SID associated with the security context that
611 * has the string representation specified by @scontext.
612 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
613 * memory is available, or 0 on success.
614 */
615int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
616{
617 char *scontext2;
618 struct context context;
619 struct role_datum *role;
620 struct type_datum *typdatum;
621 struct user_datum *usrdatum;
622 char *scontextp, *p, oldc;
623 int rc = 0;
624
625 if (!ss_initialized) {
626 int i;
627
628 for (i = 1; i < SECINITSID_NUM; i++) {
629 if (!strcmp(initial_sid_to_string[i], scontext)) {
630 *sid = i;
631 goto out;
632 }
633 }
634 *sid = SECINITSID_KERNEL;
635 goto out;
636 }
637 *sid = SECSID_NULL;
638
639 /* Copy the string so that we can modify the copy as we parse it.
640 The string should already by null terminated, but we append a
641 null suffix to the copy to avoid problems with the existing
642 attr package, which doesn't view the null terminator as part
643 of the attribute value. */
644 scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
645 if (!scontext2) {
646 rc = -ENOMEM;
647 goto out;
648 }
649 memcpy(scontext2, scontext, scontext_len);
650 scontext2[scontext_len] = 0;
651
652 context_init(&context);
653 *sid = SECSID_NULL;
654
655 POLICY_RDLOCK;
656
657 /* Parse the security context. */
658
659 rc = -EINVAL;
660 scontextp = (char *) scontext2;
661
662 /* Extract the user. */
663 p = scontextp;
664 while (*p && *p != ':')
665 p++;
666
667 if (*p == 0)
668 goto out_unlock;
669
670 *p++ = 0;
671
672 usrdatum = hashtab_search(policydb.p_users.table, scontextp);
673 if (!usrdatum)
674 goto out_unlock;
675
676 context.user = usrdatum->value;
677
678 /* Extract role. */
679 scontextp = p;
680 while (*p && *p != ':')
681 p++;
682
683 if (*p == 0)
684 goto out_unlock;
685
686 *p++ = 0;
687
688 role = hashtab_search(policydb.p_roles.table, scontextp);
689 if (!role)
690 goto out_unlock;
691 context.role = role->value;
692
693 /* Extract type. */
694 scontextp = p;
695 while (*p && *p != ':')
696 p++;
697 oldc = *p;
698 *p++ = 0;
699
700 typdatum = hashtab_search(policydb.p_types.table, scontextp);
701 if (!typdatum)
702 goto out_unlock;
703
704 context.type = typdatum->value;
705
706 rc = mls_context_to_sid(oldc, &p, &context);
707 if (rc)
708 goto out_unlock;
709
710 if ((p - scontext2) < scontext_len) {
711 rc = -EINVAL;
712 goto out_unlock;
713 }
714
715 /* Check the validity of the new context. */
716 if (!policydb_context_isvalid(&policydb, &context)) {
717 rc = -EINVAL;
718 goto out_unlock;
719 }
720 /* Obtain the new sid. */
721 rc = sidtab_context_to_sid(&sidtab, &context, sid);
722out_unlock:
723 POLICY_RDUNLOCK;
724 context_destroy(&context);
725 kfree(scontext2);
726out:
727 return rc;
728}
729
730static int compute_sid_handle_invalid_context(
731 struct context *scontext,
732 struct context *tcontext,
733 u16 tclass,
734 struct context *newcontext)
735{
736 char *s = NULL, *t = NULL, *n = NULL;
737 u32 slen, tlen, nlen;
738
739 if (context_struct_to_string(scontext, &s, &slen) < 0)
740 goto out;
741 if (context_struct_to_string(tcontext, &t, &tlen) < 0)
742 goto out;
743 if (context_struct_to_string(newcontext, &n, &nlen) < 0)
744 goto out;
745 audit_log(current->audit_context,
746 "security_compute_sid: invalid context %s"
747 " for scontext=%s"
748 " tcontext=%s"
749 " tclass=%s",
750 n, s, t, policydb.p_class_val_to_name[tclass-1]);
751out:
752 kfree(s);
753 kfree(t);
754 kfree(n);
755 if (!selinux_enforcing)
756 return 0;
757 return -EACCES;
758}
759
760static int security_compute_sid(u32 ssid,
761 u32 tsid,
762 u16 tclass,
763 u32 specified,
764 u32 *out_sid)
765{
766 struct context *scontext = NULL, *tcontext = NULL, newcontext;
767 struct role_trans *roletr = NULL;
768 struct avtab_key avkey;
769 struct avtab_datum *avdatum;
770 struct avtab_node *node;
771 unsigned int type_change = 0;
772 int rc = 0;
773
774 if (!ss_initialized) {
775 switch (tclass) {
776 case SECCLASS_PROCESS:
777 *out_sid = ssid;
778 break;
779 default:
780 *out_sid = tsid;
781 break;
782 }
783 goto out;
784 }
785
786 POLICY_RDLOCK;
787
788 scontext = sidtab_search(&sidtab, ssid);
789 if (!scontext) {
790 printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n",
791 ssid);
792 rc = -EINVAL;
793 goto out_unlock;
794 }
795 tcontext = sidtab_search(&sidtab, tsid);
796 if (!tcontext) {
797 printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n",
798 tsid);
799 rc = -EINVAL;
800 goto out_unlock;
801 }
802
803 context_init(&newcontext);
804
805 /* Set the user identity. */
806 switch (specified) {
807 case AVTAB_TRANSITION:
808 case AVTAB_CHANGE:
809 /* Use the process user identity. */
810 newcontext.user = scontext->user;
811 break;
812 case AVTAB_MEMBER:
813 /* Use the related object owner. */
814 newcontext.user = tcontext->user;
815 break;
816 }
817
818 /* Set the role and type to default values. */
819 switch (tclass) {
820 case SECCLASS_PROCESS:
821 /* Use the current role and type of process. */
822 newcontext.role = scontext->role;
823 newcontext.type = scontext->type;
824 break;
825 default:
826 /* Use the well-defined object role. */
827 newcontext.role = OBJECT_R_VAL;
828 /* Use the type of the related object. */
829 newcontext.type = tcontext->type;
830 }
831
832 /* Look for a type transition/member/change rule. */
833 avkey.source_type = scontext->type;
834 avkey.target_type = tcontext->type;
835 avkey.target_class = tclass;
836 avdatum = avtab_search(&policydb.te_avtab, &avkey, AVTAB_TYPE);
837
838 /* If no permanent rule, also check for enabled conditional rules */
839 if(!avdatum) {
840 node = avtab_search_node(&policydb.te_cond_avtab, &avkey, specified);
841 for (; node != NULL; node = avtab_search_node_next(node, specified)) {
842 if (node->datum.specified & AVTAB_ENABLED) {
843 avdatum = &node->datum;
844 break;
845 }
846 }
847 }
848
849 type_change = (avdatum && (avdatum->specified & specified));
850 if (type_change) {
851 /* Use the type from the type transition/member/change rule. */
852 switch (specified) {
853 case AVTAB_TRANSITION:
854 newcontext.type = avtab_transition(avdatum);
855 break;
856 case AVTAB_MEMBER:
857 newcontext.type = avtab_member(avdatum);
858 break;
859 case AVTAB_CHANGE:
860 newcontext.type = avtab_change(avdatum);
861 break;
862 }
863 }
864
865 /* Check for class-specific changes. */
866 switch (tclass) {
867 case SECCLASS_PROCESS:
868 if (specified & AVTAB_TRANSITION) {
869 /* Look for a role transition rule. */
870 for (roletr = policydb.role_tr; roletr;
871 roletr = roletr->next) {
872 if (roletr->role == scontext->role &&
873 roletr->type == tcontext->type) {
874 /* Use the role transition rule. */
875 newcontext.role = roletr->new_role;
876 break;
877 }
878 }
879 }
880 break;
881 default:
882 break;
883 }
884
885 /* Set the MLS attributes.
886 This is done last because it may allocate memory. */
887 rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
888 if (rc)
889 goto out_unlock;
890
891 /* Check the validity of the context. */
892 if (!policydb_context_isvalid(&policydb, &newcontext)) {
893 rc = compute_sid_handle_invalid_context(scontext,
894 tcontext,
895 tclass,
896 &newcontext);
897 if (rc)
898 goto out_unlock;
899 }
900 /* Obtain the sid for the context. */
901 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
902out_unlock:
903 POLICY_RDUNLOCK;
904 context_destroy(&newcontext);
905out:
906 return rc;
907}
908
909/**
910 * security_transition_sid - Compute the SID for a new subject/object.
911 * @ssid: source security identifier
912 * @tsid: target security identifier
913 * @tclass: target security class
914 * @out_sid: security identifier for new subject/object
915 *
916 * Compute a SID to use for labeling a new subject or object in the
917 * class @tclass based on a SID pair (@ssid, @tsid).
918 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
919 * if insufficient memory is available, or %0 if the new SID was
920 * computed successfully.
921 */
922int security_transition_sid(u32 ssid,
923 u32 tsid,
924 u16 tclass,
925 u32 *out_sid)
926{
927 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
928}
929
930/**
931 * security_member_sid - Compute the SID for member selection.
932 * @ssid: source security identifier
933 * @tsid: target security identifier
934 * @tclass: target security class
935 * @out_sid: security identifier for selected member
936 *
937 * Compute a SID to use when selecting a member of a polyinstantiated
938 * object of class @tclass based on a SID pair (@ssid, @tsid).
939 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
940 * if insufficient memory is available, or %0 if the SID was
941 * computed successfully.
942 */
943int security_member_sid(u32 ssid,
944 u32 tsid,
945 u16 tclass,
946 u32 *out_sid)
947{
948 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
949}
950
951/**
952 * security_change_sid - Compute the SID for object relabeling.
953 * @ssid: source security identifier
954 * @tsid: target security identifier
955 * @tclass: target security class
956 * @out_sid: security identifier for selected member
957 *
958 * Compute a SID to use for relabeling an object of class @tclass
959 * based on a SID pair (@ssid, @tsid).
960 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
961 * if insufficient memory is available, or %0 if the SID was
962 * computed successfully.
963 */
964int security_change_sid(u32 ssid,
965 u32 tsid,
966 u16 tclass,
967 u32 *out_sid)
968{
969 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
970}
971
972/*
973 * Verify that each permission that is defined under the
974 * existing policy is still defined with the same value
975 * in the new policy.
976 */
977static int validate_perm(void *key, void *datum, void *p)
978{
979 struct hashtab *h;
980 struct perm_datum *perdatum, *perdatum2;
981 int rc = 0;
982
983
984 h = p;
985 perdatum = datum;
986
987 perdatum2 = hashtab_search(h, key);
988 if (!perdatum2) {
989 printk(KERN_ERR "security: permission %s disappeared",
990 (char *)key);
991 rc = -ENOENT;
992 goto out;
993 }
994 if (perdatum->value != perdatum2->value) {
995 printk(KERN_ERR "security: the value of permission %s changed",
996 (char *)key);
997 rc = -EINVAL;
998 }
999out:
1000 return rc;
1001}
1002
1003/*
1004 * Verify that each class that is defined under the
1005 * existing policy is still defined with the same
1006 * attributes in the new policy.
1007 */
1008static int validate_class(void *key, void *datum, void *p)
1009{
1010 struct policydb *newp;
1011 struct class_datum *cladatum, *cladatum2;
1012 int rc;
1013
1014 newp = p;
1015 cladatum = datum;
1016
1017 cladatum2 = hashtab_search(newp->p_classes.table, key);
1018 if (!cladatum2) {
1019 printk(KERN_ERR "security: class %s disappeared\n",
1020 (char *)key);
1021 rc = -ENOENT;
1022 goto out;
1023 }
1024 if (cladatum->value != cladatum2->value) {
1025 printk(KERN_ERR "security: the value of class %s changed\n",
1026 (char *)key);
1027 rc = -EINVAL;
1028 goto out;
1029 }
1030 if ((cladatum->comdatum && !cladatum2->comdatum) ||
1031 (!cladatum->comdatum && cladatum2->comdatum)) {
1032 printk(KERN_ERR "security: the inherits clause for the access "
1033 "vector definition for class %s changed\n", (char *)key);
1034 rc = -EINVAL;
1035 goto out;
1036 }
1037 if (cladatum->comdatum) {
1038 rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm,
1039 cladatum2->comdatum->permissions.table);
1040 if (rc) {
1041 printk(" in the access vector definition for class "
1042 "%s\n", (char *)key);
1043 goto out;
1044 }
1045 }
1046 rc = hashtab_map(cladatum->permissions.table, validate_perm,
1047 cladatum2->permissions.table);
1048 if (rc)
1049 printk(" in access vector definition for class %s\n",
1050 (char *)key);
1051out:
1052 return rc;
1053}
1054
1055/* Clone the SID into the new SID table. */
1056static int clone_sid(u32 sid,
1057 struct context *context,
1058 void *arg)
1059{
1060 struct sidtab *s = arg;
1061
1062 return sidtab_insert(s, sid, context);
1063}
1064
1065static inline int convert_context_handle_invalid_context(struct context *context)
1066{
1067 int rc = 0;
1068
1069 if (selinux_enforcing) {
1070 rc = -EINVAL;
1071 } else {
1072 char *s;
1073 u32 len;
1074
1075 context_struct_to_string(context, &s, &len);
1076 printk(KERN_ERR "security: context %s is invalid\n", s);
1077 kfree(s);
1078 }
1079 return rc;
1080}
1081
1082struct convert_context_args {
1083 struct policydb *oldp;
1084 struct policydb *newp;
1085};
1086
1087/*
1088 * Convert the values in the security context
1089 * structure `c' from the values specified
1090 * in the policy `p->oldp' to the values specified
1091 * in the policy `p->newp'. Verify that the
1092 * context is valid under the new policy.
1093 */
1094static int convert_context(u32 key,
1095 struct context *c,
1096 void *p)
1097{
1098 struct convert_context_args *args;
1099 struct context oldc;
1100 struct role_datum *role;
1101 struct type_datum *typdatum;
1102 struct user_datum *usrdatum;
1103 char *s;
1104 u32 len;
1105 int rc;
1106
1107 args = p;
1108
1109 rc = context_cpy(&oldc, c);
1110 if (rc)
1111 goto out;
1112
1113 rc = -EINVAL;
1114
1115 /* Convert the user. */
1116 usrdatum = hashtab_search(args->newp->p_users.table,
1117 args->oldp->p_user_val_to_name[c->user - 1]);
1118 if (!usrdatum) {
1119 goto bad;
1120 }
1121 c->user = usrdatum->value;
1122
1123 /* Convert the role. */
1124 role = hashtab_search(args->newp->p_roles.table,
1125 args->oldp->p_role_val_to_name[c->role - 1]);
1126 if (!role) {
1127 goto bad;
1128 }
1129 c->role = role->value;
1130
1131 /* Convert the type. */
1132 typdatum = hashtab_search(args->newp->p_types.table,
1133 args->oldp->p_type_val_to_name[c->type - 1]);
1134 if (!typdatum) {
1135 goto bad;
1136 }
1137 c->type = typdatum->value;
1138
1139 rc = mls_convert_context(args->oldp, args->newp, c);
1140 if (rc)
1141 goto bad;
1142
1143 /* Check the validity of the new context. */
1144 if (!policydb_context_isvalid(args->newp, c)) {
1145 rc = convert_context_handle_invalid_context(&oldc);
1146 if (rc)
1147 goto bad;
1148 }
1149
1150 context_destroy(&oldc);
1151out:
1152 return rc;
1153bad:
1154 context_struct_to_string(&oldc, &s, &len);
1155 context_destroy(&oldc);
1156 printk(KERN_ERR "security: invalidating context %s\n", s);
1157 kfree(s);
1158 goto out;
1159}
1160
1161extern void selinux_complete_init(void);
1162
1163/**
1164 * security_load_policy - Load a security policy configuration.
1165 * @data: binary policy data
1166 * @len: length of data in bytes
1167 *
1168 * Load a new set of security policy configuration data,
1169 * validate it and convert the SID table as necessary.
1170 * This function will flush the access vector cache after
1171 * loading the new policy.
1172 */
1173int security_load_policy(void *data, size_t len)
1174{
1175 struct policydb oldpolicydb, newpolicydb;
1176 struct sidtab oldsidtab, newsidtab;
1177 struct convert_context_args args;
1178 u32 seqno;
1179 int rc = 0;
1180 struct policy_file file = { data, len }, *fp = &file;
1181
1182 LOAD_LOCK;
1183
1184 if (!ss_initialized) {
1185 avtab_cache_init();
1186 if (policydb_read(&policydb, fp)) {
1187 LOAD_UNLOCK;
1188 avtab_cache_destroy();
1189 return -EINVAL;
1190 }
1191 if (policydb_load_isids(&policydb, &sidtab)) {
1192 LOAD_UNLOCK;
1193 policydb_destroy(&policydb);
1194 avtab_cache_destroy();
1195 return -EINVAL;
1196 }
1197 policydb_loaded_version = policydb.policyvers;
1198 ss_initialized = 1;
1199
1200 LOAD_UNLOCK;
1201 selinux_complete_init();
1202 return 0;
1203 }
1204
1205#if 0
1206 sidtab_hash_eval(&sidtab, "sids");
1207#endif
1208
1209 if (policydb_read(&newpolicydb, fp)) {
1210 LOAD_UNLOCK;
1211 return -EINVAL;
1212 }
1213
1214 sidtab_init(&newsidtab);
1215
1216 /* Verify that the existing classes did not change. */
1217 if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) {
1218 printk(KERN_ERR "security: the definition of an existing "
1219 "class changed\n");
1220 rc = -EINVAL;
1221 goto err;
1222 }
1223
1224 /* Clone the SID table. */
1225 sidtab_shutdown(&sidtab);
1226 if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
1227 rc = -ENOMEM;
1228 goto err;
1229 }
1230
1231 /* Convert the internal representations of contexts
1232 in the new SID table and remove invalid SIDs. */
1233 args.oldp = &policydb;
1234 args.newp = &newpolicydb;
1235 sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
1236
1237 /* Save the old policydb and SID table to free later. */
1238 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1239 sidtab_set(&oldsidtab, &sidtab);
1240
1241 /* Install the new policydb and SID table. */
1242 POLICY_WRLOCK;
1243 memcpy(&policydb, &newpolicydb, sizeof policydb);
1244 sidtab_set(&sidtab, &newsidtab);
1245 seqno = ++latest_granting;
1246 policydb_loaded_version = policydb.policyvers;
1247 POLICY_WRUNLOCK;
1248 LOAD_UNLOCK;
1249
1250 /* Free the old policydb and SID table. */
1251 policydb_destroy(&oldpolicydb);
1252 sidtab_destroy(&oldsidtab);
1253
1254 avc_ss_reset(seqno);
1255 selnl_notify_policyload(seqno);
1256
1257 return 0;
1258
1259err:
1260 LOAD_UNLOCK;
1261 sidtab_destroy(&newsidtab);
1262 policydb_destroy(&newpolicydb);
1263 return rc;
1264
1265}
1266
1267/**
1268 * security_port_sid - Obtain the SID for a port.
1269 * @domain: communication domain aka address family
1270 * @type: socket type
1271 * @protocol: protocol number
1272 * @port: port number
1273 * @out_sid: security identifier
1274 */
1275int security_port_sid(u16 domain,
1276 u16 type,
1277 u8 protocol,
1278 u16 port,
1279 u32 *out_sid)
1280{
1281 struct ocontext *c;
1282 int rc = 0;
1283
1284 POLICY_RDLOCK;
1285
1286 c = policydb.ocontexts[OCON_PORT];
1287 while (c) {
1288 if (c->u.port.protocol == protocol &&
1289 c->u.port.low_port <= port &&
1290 c->u.port.high_port >= port)
1291 break;
1292 c = c->next;
1293 }
1294
1295 if (c) {
1296 if (!c->sid[0]) {
1297 rc = sidtab_context_to_sid(&sidtab,
1298 &c->context[0],
1299 &c->sid[0]);
1300 if (rc)
1301 goto out;
1302 }
1303 *out_sid = c->sid[0];
1304 } else {
1305 *out_sid = SECINITSID_PORT;
1306 }
1307
1308out:
1309 POLICY_RDUNLOCK;
1310 return rc;
1311}
1312
1313/**
1314 * security_netif_sid - Obtain the SID for a network interface.
1315 * @name: interface name
1316 * @if_sid: interface SID
1317 * @msg_sid: default SID for received packets
1318 */
1319int security_netif_sid(char *name,
1320 u32 *if_sid,
1321 u32 *msg_sid)
1322{
1323 int rc = 0;
1324 struct ocontext *c;
1325
1326 POLICY_RDLOCK;
1327
1328 c = policydb.ocontexts[OCON_NETIF];
1329 while (c) {
1330 if (strcmp(name, c->u.name) == 0)
1331 break;
1332 c = c->next;
1333 }
1334
1335 if (c) {
1336 if (!c->sid[0] || !c->sid[1]) {
1337 rc = sidtab_context_to_sid(&sidtab,
1338 &c->context[0],
1339 &c->sid[0]);
1340 if (rc)
1341 goto out;
1342 rc = sidtab_context_to_sid(&sidtab,
1343 &c->context[1],
1344 &c->sid[1]);
1345 if (rc)
1346 goto out;
1347 }
1348 *if_sid = c->sid[0];
1349 *msg_sid = c->sid[1];
1350 } else {
1351 *if_sid = SECINITSID_NETIF;
1352 *msg_sid = SECINITSID_NETMSG;
1353 }
1354
1355out:
1356 POLICY_RDUNLOCK;
1357 return rc;
1358}
1359
1360static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1361{
1362 int i, fail = 0;
1363
1364 for(i = 0; i < 4; i++)
1365 if(addr[i] != (input[i] & mask[i])) {
1366 fail = 1;
1367 break;
1368 }
1369
1370 return !fail;
1371}
1372
1373/**
1374 * security_node_sid - Obtain the SID for a node (host).
1375 * @domain: communication domain aka address family
1376 * @addrp: address
1377 * @addrlen: address length in bytes
1378 * @out_sid: security identifier
1379 */
1380int security_node_sid(u16 domain,
1381 void *addrp,
1382 u32 addrlen,
1383 u32 *out_sid)
1384{
1385 int rc = 0;
1386 struct ocontext *c;
1387
1388 POLICY_RDLOCK;
1389
1390 switch (domain) {
1391 case AF_INET: {
1392 u32 addr;
1393
1394 if (addrlen != sizeof(u32)) {
1395 rc = -EINVAL;
1396 goto out;
1397 }
1398
1399 addr = *((u32 *)addrp);
1400
1401 c = policydb.ocontexts[OCON_NODE];
1402 while (c) {
1403 if (c->u.node.addr == (addr & c->u.node.mask))
1404 break;
1405 c = c->next;
1406 }
1407 break;
1408 }
1409
1410 case AF_INET6:
1411 if (addrlen != sizeof(u64) * 2) {
1412 rc = -EINVAL;
1413 goto out;
1414 }
1415 c = policydb.ocontexts[OCON_NODE6];
1416 while (c) {
1417 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
1418 c->u.node6.mask))
1419 break;
1420 c = c->next;
1421 }
1422 break;
1423
1424 default:
1425 *out_sid = SECINITSID_NODE;
1426 goto out;
1427 }
1428
1429 if (c) {
1430 if (!c->sid[0]) {
1431 rc = sidtab_context_to_sid(&sidtab,
1432 &c->context[0],
1433 &c->sid[0]);
1434 if (rc)
1435 goto out;
1436 }
1437 *out_sid = c->sid[0];
1438 } else {
1439 *out_sid = SECINITSID_NODE;
1440 }
1441
1442out:
1443 POLICY_RDUNLOCK;
1444 return rc;
1445}
1446
1447#define SIDS_NEL 25
1448
1449/**
1450 * security_get_user_sids - Obtain reachable SIDs for a user.
1451 * @fromsid: starting SID
1452 * @username: username
1453 * @sids: array of reachable SIDs for user
1454 * @nel: number of elements in @sids
1455 *
1456 * Generate the set of SIDs for legal security contexts
1457 * for a given user that can be reached by @fromsid.
1458 * Set *@sids to point to a dynamically allocated
1459 * array containing the set of SIDs. Set *@nel to the
1460 * number of elements in the array.
1461 */
1462
1463int security_get_user_sids(u32 fromsid,
1464 char *username,
1465 u32 **sids,
1466 u32 *nel)
1467{
1468 struct context *fromcon, usercon;
1469 u32 *mysids, *mysids2, sid;
1470 u32 mynel = 0, maxnel = SIDS_NEL;
1471 struct user_datum *user;
1472 struct role_datum *role;
1473 struct av_decision avd;
1474 int rc = 0, i, j;
1475
1476 if (!ss_initialized) {
1477 *sids = NULL;
1478 *nel = 0;
1479 goto out;
1480 }
1481
1482 POLICY_RDLOCK;
1483
1484 fromcon = sidtab_search(&sidtab, fromsid);
1485 if (!fromcon) {
1486 rc = -EINVAL;
1487 goto out_unlock;
1488 }
1489
1490 user = hashtab_search(policydb.p_users.table, username);
1491 if (!user) {
1492 rc = -EINVAL;
1493 goto out_unlock;
1494 }
1495 usercon.user = user->value;
1496
1497 mysids = kmalloc(maxnel*sizeof(*mysids), GFP_ATOMIC);
1498 if (!mysids) {
1499 rc = -ENOMEM;
1500 goto out_unlock;
1501 }
1502 memset(mysids, 0, maxnel*sizeof(*mysids));
1503
1504 for (i = ebitmap_startbit(&user->roles); i < ebitmap_length(&user->roles); i++) {
1505 if (!ebitmap_get_bit(&user->roles, i))
1506 continue;
1507 role = policydb.role_val_to_struct[i];
1508 usercon.role = i+1;
1509 for (j = ebitmap_startbit(&role->types); j < ebitmap_length(&role->types); j++) {
1510 if (!ebitmap_get_bit(&role->types, j))
1511 continue;
1512 usercon.type = j+1;
1513
1514 if (mls_setup_user_range(fromcon, user, &usercon))
1515 continue;
1516
1517 rc = context_struct_compute_av(fromcon, &usercon,
1518 SECCLASS_PROCESS,
1519 PROCESS__TRANSITION,
1520 &avd);
1521 if (rc || !(avd.allowed & PROCESS__TRANSITION))
1522 continue;
1523 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
1524 if (rc) {
1525 kfree(mysids);
1526 goto out_unlock;
1527 }
1528 if (mynel < maxnel) {
1529 mysids[mynel++] = sid;
1530 } else {
1531 maxnel += SIDS_NEL;
1532 mysids2 = kmalloc(maxnel*sizeof(*mysids2), GFP_ATOMIC);
1533 if (!mysids2) {
1534 rc = -ENOMEM;
1535 kfree(mysids);
1536 goto out_unlock;
1537 }
1538 memset(mysids2, 0, maxnel*sizeof(*mysids2));
1539 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
1540 kfree(mysids);
1541 mysids = mysids2;
1542 mysids[mynel++] = sid;
1543 }
1544 }
1545 }
1546
1547 *sids = mysids;
1548 *nel = mynel;
1549
1550out_unlock:
1551 POLICY_RDUNLOCK;
1552out:
1553 return rc;
1554}
1555
1556/**
1557 * security_genfs_sid - Obtain a SID for a file in a filesystem
1558 * @fstype: filesystem type
1559 * @path: path from root of mount
1560 * @sclass: file security class
1561 * @sid: SID for path
1562 *
1563 * Obtain a SID to use for a file in a filesystem that
1564 * cannot support xattr or use a fixed labeling behavior like
1565 * transition SIDs or task SIDs.
1566 */
1567int security_genfs_sid(const char *fstype,
1568 char *path,
1569 u16 sclass,
1570 u32 *sid)
1571{
1572 int len;
1573 struct genfs *genfs;
1574 struct ocontext *c;
1575 int rc = 0, cmp = 0;
1576
1577 POLICY_RDLOCK;
1578
1579 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
1580 cmp = strcmp(fstype, genfs->fstype);
1581 if (cmp <= 0)
1582 break;
1583 }
1584
1585 if (!genfs || cmp) {
1586 *sid = SECINITSID_UNLABELED;
1587 rc = -ENOENT;
1588 goto out;
1589 }
1590
1591 for (c = genfs->head; c; c = c->next) {
1592 len = strlen(c->u.name);
1593 if ((!c->v.sclass || sclass == c->v.sclass) &&
1594 (strncmp(c->u.name, path, len) == 0))
1595 break;
1596 }
1597
1598 if (!c) {
1599 *sid = SECINITSID_UNLABELED;
1600 rc = -ENOENT;
1601 goto out;
1602 }
1603
1604 if (!c->sid[0]) {
1605 rc = sidtab_context_to_sid(&sidtab,
1606 &c->context[0],
1607 &c->sid[0]);
1608 if (rc)
1609 goto out;
1610 }
1611
1612 *sid = c->sid[0];
1613out:
1614 POLICY_RDUNLOCK;
1615 return rc;
1616}
1617
1618/**
1619 * security_fs_use - Determine how to handle labeling for a filesystem.
1620 * @fstype: filesystem type
1621 * @behavior: labeling behavior
1622 * @sid: SID for filesystem (superblock)
1623 */
1624int security_fs_use(
1625 const char *fstype,
1626 unsigned int *behavior,
1627 u32 *sid)
1628{
1629 int rc = 0;
1630 struct ocontext *c;
1631
1632 POLICY_RDLOCK;
1633
1634 c = policydb.ocontexts[OCON_FSUSE];
1635 while (c) {
1636 if (strcmp(fstype, c->u.name) == 0)
1637 break;
1638 c = c->next;
1639 }
1640
1641 if (c) {
1642 *behavior = c->v.behavior;
1643 if (!c->sid[0]) {
1644 rc = sidtab_context_to_sid(&sidtab,
1645 &c->context[0],
1646 &c->sid[0]);
1647 if (rc)
1648 goto out;
1649 }
1650 *sid = c->sid[0];
1651 } else {
1652 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
1653 if (rc) {
1654 *behavior = SECURITY_FS_USE_NONE;
1655 rc = 0;
1656 } else {
1657 *behavior = SECURITY_FS_USE_GENFS;
1658 }
1659 }
1660
1661out:
1662 POLICY_RDUNLOCK;
1663 return rc;
1664}
1665
1666int security_get_bools(int *len, char ***names, int **values)
1667{
1668 int i, rc = -ENOMEM;
1669
1670 POLICY_RDLOCK;
1671 *names = NULL;
1672 *values = NULL;
1673
1674 *len = policydb.p_bools.nprim;
1675 if (!*len) {
1676 rc = 0;
1677 goto out;
1678 }
1679
1680 *names = (char**)kmalloc(sizeof(char*) * *len, GFP_ATOMIC);
1681 if (!*names)
1682 goto err;
1683 memset(*names, 0, sizeof(char*) * *len);
1684
1685 *values = (int*)kmalloc(sizeof(int) * *len, GFP_ATOMIC);
1686 if (!*values)
1687 goto err;
1688
1689 for (i = 0; i < *len; i++) {
1690 size_t name_len;
1691 (*values)[i] = policydb.bool_val_to_struct[i]->state;
1692 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
1693 (*names)[i] = (char*)kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
1694 if (!(*names)[i])
1695 goto err;
1696 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
1697 (*names)[i][name_len - 1] = 0;
1698 }
1699 rc = 0;
1700out:
1701 POLICY_RDUNLOCK;
1702 return rc;
1703err:
1704 if (*names) {
1705 for (i = 0; i < *len; i++)
1706 if ((*names)[i])
1707 kfree((*names)[i]);
1708 }
1709 if (*values)
1710 kfree(*values);
1711 goto out;
1712}
1713
1714
1715int security_set_bools(int len, int *values)
1716{
1717 int i, rc = 0;
1718 int lenp, seqno = 0;
1719 struct cond_node *cur;
1720
1721 POLICY_WRLOCK;
1722
1723 lenp = policydb.p_bools.nprim;
1724 if (len != lenp) {
1725 rc = -EFAULT;
1726 goto out;
1727 }
1728
1729 printk(KERN_INFO "security: committed booleans { ");
1730 for (i = 0; i < len; i++) {
1731 if (values[i]) {
1732 policydb.bool_val_to_struct[i]->state = 1;
1733 } else {
1734 policydb.bool_val_to_struct[i]->state = 0;
1735 }
1736 if (i != 0)
1737 printk(", ");
1738 printk("%s:%d", policydb.p_bool_val_to_name[i],
1739 policydb.bool_val_to_struct[i]->state);
1740 }
1741 printk(" }\n");
1742
1743 for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
1744 rc = evaluate_cond_node(&policydb, cur);
1745 if (rc)
1746 goto out;
1747 }
1748
1749 seqno = ++latest_granting;
1750
1751out:
1752 POLICY_WRUNLOCK;
1753 if (!rc) {
1754 avc_ss_reset(seqno);
1755 selnl_notify_policyload(seqno);
1756 }
1757 return rc;
1758}
1759
1760int security_get_bool_value(int bool)
1761{
1762 int rc = 0;
1763 int len;
1764
1765 POLICY_RDLOCK;
1766
1767 len = policydb.p_bools.nprim;
1768 if (bool >= len) {
1769 rc = -EFAULT;
1770 goto out;
1771 }
1772
1773 rc = policydb.bool_val_to_struct[bool]->state;
1774out:
1775 POLICY_RDUNLOCK;
1776 return rc;
1777}
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-13 03:45:36 -0500