selinux: introduce permissive types
[linux-2.6.git] / security / selinux / ss / services.c
1 /*
2  * Implementation of the security services.
3  *
4  * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
5  *           James Morris <jmorris@redhat.com>
6  *
7  * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
8  *
9  *      Support for enhanced MLS infrastructure.
10  *      Support for context based audit filters.
11  *
12  * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
13  *
14  *      Added conditional policy language extensions
15  *
16  * Updated: Hewlett-Packard <paul.moore@hp.com>
17  *
18  *      Added support for NetLabel
19  *      Added support for the policy capability bitmap
20  *
21  * Updated: Chad Sellers <csellers@tresys.com>
22  *
23  *  Added validation of kernel classes and permissions
24  *
25  * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
26  * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
27  * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
28  * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
29  *      This program is free software; you can redistribute it and/or modify
30  *      it under the terms of the GNU General Public License as published by
31  *      the Free Software Foundation, version 2.
32  */
33 #include <linux/kernel.h>
34 #include <linux/slab.h>
35 #include <linux/string.h>
36 #include <linux/spinlock.h>
37 #include <linux/rcupdate.h>
38 #include <linux/errno.h>
39 #include <linux/in.h>
40 #include <linux/sched.h>
41 #include <linux/audit.h>
42 #include <linux/mutex.h>
43 #include <net/netlabel.h>
44
45 #include "flask.h"
46 #include "avc.h"
47 #include "avc_ss.h"
48 #include "security.h"
49 #include "context.h"
50 #include "policydb.h"
51 #include "sidtab.h"
52 #include "services.h"
53 #include "conditional.h"
54 #include "mls.h"
55 #include "objsec.h"
56 #include "netlabel.h"
57 #include "xfrm.h"
58 #include "ebitmap.h"
59
60 extern void selnl_notify_policyload(u32 seqno);
61 unsigned int policydb_loaded_version;
62
63 int selinux_policycap_netpeer;
64 int selinux_policycap_openperm;
65
66 /*
67  * This is declared in avc.c
68  */
69 extern const struct selinux_class_perm selinux_class_perm;
70
71 static DEFINE_RWLOCK(policy_rwlock);
72 #define POLICY_RDLOCK read_lock(&policy_rwlock)
73 #define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
74 #define POLICY_RDUNLOCK read_unlock(&policy_rwlock)
75 #define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock)
76
77 static DEFINE_MUTEX(load_mutex);
78 #define LOAD_LOCK mutex_lock(&load_mutex)
79 #define LOAD_UNLOCK mutex_unlock(&load_mutex)
80
81 static struct sidtab sidtab;
82 struct policydb policydb;
83 int ss_initialized = 0;
84
85 /*
86  * The largest sequence number that has been used when
87  * providing an access decision to the access vector cache.
88  * The sequence number only changes when a policy change
89  * occurs.
90  */
91 static u32 latest_granting = 0;
92
93 /* Forward declaration. */
94 static int context_struct_to_string(struct context *context, char **scontext,
95                                     u32 *scontext_len);
96
97 /*
98  * Return the boolean value of a constraint expression
99  * when it is applied to the specified source and target
100  * security contexts.
101  *
102  * xcontext is a special beast...  It is used by the validatetrans rules
103  * only.  For these rules, scontext is the context before the transition,
104  * tcontext is the context after the transition, and xcontext is the context
105  * of the process performing the transition.  All other callers of
106  * constraint_expr_eval should pass in NULL for xcontext.
107  */
108 static int constraint_expr_eval(struct context *scontext,
109                                 struct context *tcontext,
110                                 struct context *xcontext,
111                                 struct constraint_expr *cexpr)
112 {
113         u32 val1, val2;
114         struct context *c;
115         struct role_datum *r1, *r2;
116         struct mls_level *l1, *l2;
117         struct constraint_expr *e;
118         int s[CEXPR_MAXDEPTH];
119         int sp = -1;
120
121         for (e = cexpr; e; e = e->next) {
122                 switch (e->expr_type) {
123                 case CEXPR_NOT:
124                         BUG_ON(sp < 0);
125                         s[sp] = !s[sp];
126                         break;
127                 case CEXPR_AND:
128                         BUG_ON(sp < 1);
129                         sp--;
130                         s[sp] &= s[sp+1];
131                         break;
132                 case CEXPR_OR:
133                         BUG_ON(sp < 1);
134                         sp--;
135                         s[sp] |= s[sp+1];
136                         break;
137                 case CEXPR_ATTR:
138                         if (sp == (CEXPR_MAXDEPTH-1))
139                                 return 0;
140                         switch (e->attr) {
141                         case CEXPR_USER:
142                                 val1 = scontext->user;
143                                 val2 = tcontext->user;
144                                 break;
145                         case CEXPR_TYPE:
146                                 val1 = scontext->type;
147                                 val2 = tcontext->type;
148                                 break;
149                         case CEXPR_ROLE:
150                                 val1 = scontext->role;
151                                 val2 = tcontext->role;
152                                 r1 = policydb.role_val_to_struct[val1 - 1];
153                                 r2 = policydb.role_val_to_struct[val2 - 1];
154                                 switch (e->op) {
155                                 case CEXPR_DOM:
156                                         s[++sp] = ebitmap_get_bit(&r1->dominates,
157                                                                   val2 - 1);
158                                         continue;
159                                 case CEXPR_DOMBY:
160                                         s[++sp] = ebitmap_get_bit(&r2->dominates,
161                                                                   val1 - 1);
162                                         continue;
163                                 case CEXPR_INCOMP:
164                                         s[++sp] = ( !ebitmap_get_bit(&r1->dominates,
165                                                                      val2 - 1) &&
166                                                     !ebitmap_get_bit(&r2->dominates,
167                                                                      val1 - 1) );
168                                         continue;
169                                 default:
170                                         break;
171                                 }
172                                 break;
173                         case CEXPR_L1L2:
174                                 l1 = &(scontext->range.level[0]);
175                                 l2 = &(tcontext->range.level[0]);
176                                 goto mls_ops;
177                         case CEXPR_L1H2:
178                                 l1 = &(scontext->range.level[0]);
179                                 l2 = &(tcontext->range.level[1]);
180                                 goto mls_ops;
181                         case CEXPR_H1L2:
182                                 l1 = &(scontext->range.level[1]);
183                                 l2 = &(tcontext->range.level[0]);
184                                 goto mls_ops;
185                         case CEXPR_H1H2:
186                                 l1 = &(scontext->range.level[1]);
187                                 l2 = &(tcontext->range.level[1]);
188                                 goto mls_ops;
189                         case CEXPR_L1H1:
190                                 l1 = &(scontext->range.level[0]);
191                                 l2 = &(scontext->range.level[1]);
192                                 goto mls_ops;
193                         case CEXPR_L2H2:
194                                 l1 = &(tcontext->range.level[0]);
195                                 l2 = &(tcontext->range.level[1]);
196                                 goto mls_ops;
197 mls_ops:
198                         switch (e->op) {
199                         case CEXPR_EQ:
200                                 s[++sp] = mls_level_eq(l1, l2);
201                                 continue;
202                         case CEXPR_NEQ:
203                                 s[++sp] = !mls_level_eq(l1, l2);
204                                 continue;
205                         case CEXPR_DOM:
206                                 s[++sp] = mls_level_dom(l1, l2);
207                                 continue;
208                         case CEXPR_DOMBY:
209                                 s[++sp] = mls_level_dom(l2, l1);
210                                 continue;
211                         case CEXPR_INCOMP:
212                                 s[++sp] = mls_level_incomp(l2, l1);
213                                 continue;
214                         default:
215                                 BUG();
216                                 return 0;
217                         }
218                         break;
219                         default:
220                                 BUG();
221                                 return 0;
222                         }
223
224                         switch (e->op) {
225                         case CEXPR_EQ:
226                                 s[++sp] = (val1 == val2);
227                                 break;
228                         case CEXPR_NEQ:
229                                 s[++sp] = (val1 != val2);
230                                 break;
231                         default:
232                                 BUG();
233                                 return 0;
234                         }
235                         break;
236                 case CEXPR_NAMES:
237                         if (sp == (CEXPR_MAXDEPTH-1))
238                                 return 0;
239                         c = scontext;
240                         if (e->attr & CEXPR_TARGET)
241                                 c = tcontext;
242                         else if (e->attr & CEXPR_XTARGET) {
243                                 c = xcontext;
244                                 if (!c) {
245                                         BUG();
246                                         return 0;
247                                 }
248                         }
249                         if (e->attr & CEXPR_USER)
250                                 val1 = c->user;
251                         else if (e->attr & CEXPR_ROLE)
252                                 val1 = c->role;
253                         else if (e->attr & CEXPR_TYPE)
254                                 val1 = c->type;
255                         else {
256                                 BUG();
257                                 return 0;
258                         }
259
260                         switch (e->op) {
261                         case CEXPR_EQ:
262                                 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
263                                 break;
264                         case CEXPR_NEQ:
265                                 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
266                                 break;
267                         default:
268                                 BUG();
269                                 return 0;
270                         }
271                         break;
272                 default:
273                         BUG();
274                         return 0;
275                 }
276         }
277
278         BUG_ON(sp != 0);
279         return s[0];
280 }
281
282 /*
283  * Compute access vectors based on a context structure pair for
284  * the permissions in a particular class.
285  */
286 static int context_struct_compute_av(struct context *scontext,
287                                      struct context *tcontext,
288                                      u16 tclass,
289                                      u32 requested,
290                                      struct av_decision *avd)
291 {
292         struct constraint_node *constraint;
293         struct role_allow *ra;
294         struct avtab_key avkey;
295         struct avtab_node *node;
296         struct class_datum *tclass_datum;
297         struct ebitmap *sattr, *tattr;
298         struct ebitmap_node *snode, *tnode;
299         const struct selinux_class_perm *kdefs = &selinux_class_perm;
300         unsigned int i, j;
301
302         /*
303          * Remap extended Netlink classes for old policy versions.
304          * Do this here rather than socket_type_to_security_class()
305          * in case a newer policy version is loaded, allowing sockets
306          * to remain in the correct class.
307          */
308         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
309                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
310                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
311                         tclass = SECCLASS_NETLINK_SOCKET;
312
313         /*
314          * Initialize the access vectors to the default values.
315          */
316         avd->allowed = 0;
317         avd->decided = 0xffffffff;
318         avd->auditallow = 0;
319         avd->auditdeny = 0xffffffff;
320         avd->seqno = latest_granting;
321
322         /*
323          * Check for all the invalid cases.
324          * - tclass 0
325          * - tclass > policy and > kernel
326          * - tclass > policy but is a userspace class
327          * - tclass > policy but we do not allow unknowns
328          */
329         if (unlikely(!tclass))
330                 goto inval_class;
331         if (unlikely(tclass > policydb.p_classes.nprim))
332                 if (tclass > kdefs->cts_len ||
333                     !kdefs->class_to_string[tclass - 1] ||
334                     !policydb.allow_unknown)
335                         goto inval_class;
336
337         /*
338          * Kernel class and we allow unknown so pad the allow decision
339          * the pad will be all 1 for unknown classes.
340          */
341         if (tclass <= kdefs->cts_len && policydb.allow_unknown)
342                 avd->allowed = policydb.undefined_perms[tclass - 1];
343
344         /*
345          * Not in policy. Since decision is completed (all 1 or all 0) return.
346          */
347         if (unlikely(tclass > policydb.p_classes.nprim))
348                 return 0;
349
350         tclass_datum = policydb.class_val_to_struct[tclass - 1];
351
352         /*
353          * If a specific type enforcement rule was defined for
354          * this permission check, then use it.
355          */
356         avkey.target_class = tclass;
357         avkey.specified = AVTAB_AV;
358         sattr = &policydb.type_attr_map[scontext->type - 1];
359         tattr = &policydb.type_attr_map[tcontext->type - 1];
360         ebitmap_for_each_positive_bit(sattr, snode, i) {
361                 ebitmap_for_each_positive_bit(tattr, tnode, j) {
362                         avkey.source_type = i + 1;
363                         avkey.target_type = j + 1;
364                         for (node = avtab_search_node(&policydb.te_avtab, &avkey);
365                              node != NULL;
366                              node = avtab_search_node_next(node, avkey.specified)) {
367                                 if (node->key.specified == AVTAB_ALLOWED)
368                                         avd->allowed |= node->datum.data;
369                                 else if (node->key.specified == AVTAB_AUDITALLOW)
370                                         avd->auditallow |= node->datum.data;
371                                 else if (node->key.specified == AVTAB_AUDITDENY)
372                                         avd->auditdeny &= node->datum.data;
373                         }
374
375                         /* Check conditional av table for additional permissions */
376                         cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
377
378                 }
379         }
380
381         /*
382          * Remove any permissions prohibited by a constraint (this includes
383          * the MLS policy).
384          */
385         constraint = tclass_datum->constraints;
386         while (constraint) {
387                 if ((constraint->permissions & (avd->allowed)) &&
388                     !constraint_expr_eval(scontext, tcontext, NULL,
389                                           constraint->expr)) {
390                         avd->allowed = (avd->allowed) & ~(constraint->permissions);
391                 }
392                 constraint = constraint->next;
393         }
394
395         /*
396          * If checking process transition permission and the
397          * role is changing, then check the (current_role, new_role)
398          * pair.
399          */
400         if (tclass == SECCLASS_PROCESS &&
401             (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
402             scontext->role != tcontext->role) {
403                 for (ra = policydb.role_allow; ra; ra = ra->next) {
404                         if (scontext->role == ra->role &&
405                             tcontext->role == ra->new_role)
406                                 break;
407                 }
408                 if (!ra)
409                         avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
410                                                         PROCESS__DYNTRANSITION);
411         }
412
413         return 0;
414
415 inval_class:
416         printk(KERN_ERR "%s:  unrecognized class %d\n", __func__, tclass);
417         return -EINVAL;
418 }
419
420 /*
421  * Given a sid find if the type has the permissive flag set
422  */
423 int security_permissive_sid(u32 sid)
424 {
425         struct context *context;
426         u32 type;
427         int rc;
428
429         POLICY_RDLOCK;
430
431         context = sidtab_search(&sidtab, sid);
432         BUG_ON(!context);
433
434         type = context->type;
435         /*
436          * we are intentionally using type here, not type-1, the 0th bit may
437          * someday indicate that we are globally setting permissive in policy.
438          */
439         rc = ebitmap_get_bit(&policydb.permissive_map, type);
440
441         POLICY_RDUNLOCK;
442         return rc;
443 }
444
445 static int security_validtrans_handle_fail(struct context *ocontext,
446                                            struct context *ncontext,
447                                            struct context *tcontext,
448                                            u16 tclass)
449 {
450         char *o = NULL, *n = NULL, *t = NULL;
451         u32 olen, nlen, tlen;
452
453         if (context_struct_to_string(ocontext, &o, &olen) < 0)
454                 goto out;
455         if (context_struct_to_string(ncontext, &n, &nlen) < 0)
456                 goto out;
457         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
458                 goto out;
459         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
460                   "security_validate_transition:  denied for"
461                   " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
462                   o, n, t, policydb.p_class_val_to_name[tclass-1]);
463 out:
464         kfree(o);
465         kfree(n);
466         kfree(t);
467
468         if (!selinux_enforcing)
469                 return 0;
470         return -EPERM;
471 }
472
473 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
474                                  u16 tclass)
475 {
476         struct context *ocontext;
477         struct context *ncontext;
478         struct context *tcontext;
479         struct class_datum *tclass_datum;
480         struct constraint_node *constraint;
481         int rc = 0;
482
483         if (!ss_initialized)
484                 return 0;
485
486         POLICY_RDLOCK;
487
488         /*
489          * Remap extended Netlink classes for old policy versions.
490          * Do this here rather than socket_type_to_security_class()
491          * in case a newer policy version is loaded, allowing sockets
492          * to remain in the correct class.
493          */
494         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
495                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
496                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
497                         tclass = SECCLASS_NETLINK_SOCKET;
498
499         if (!tclass || tclass > policydb.p_classes.nprim) {
500                 printk(KERN_ERR "security_validate_transition:  "
501                        "unrecognized class %d\n", tclass);
502                 rc = -EINVAL;
503                 goto out;
504         }
505         tclass_datum = policydb.class_val_to_struct[tclass - 1];
506
507         ocontext = sidtab_search(&sidtab, oldsid);
508         if (!ocontext) {
509                 printk(KERN_ERR "security_validate_transition: "
510                        " unrecognized SID %d\n", oldsid);
511                 rc = -EINVAL;
512                 goto out;
513         }
514
515         ncontext = sidtab_search(&sidtab, newsid);
516         if (!ncontext) {
517                 printk(KERN_ERR "security_validate_transition: "
518                        " unrecognized SID %d\n", newsid);
519                 rc = -EINVAL;
520                 goto out;
521         }
522
523         tcontext = sidtab_search(&sidtab, tasksid);
524         if (!tcontext) {
525                 printk(KERN_ERR "security_validate_transition: "
526                        " unrecognized SID %d\n", tasksid);
527                 rc = -EINVAL;
528                 goto out;
529         }
530
531         constraint = tclass_datum->validatetrans;
532         while (constraint) {
533                 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
534                                           constraint->expr)) {
535                         rc = security_validtrans_handle_fail(ocontext, ncontext,
536                                                              tcontext, tclass);
537                         goto out;
538                 }
539                 constraint = constraint->next;
540         }
541
542 out:
543         POLICY_RDUNLOCK;
544         return rc;
545 }
546
547 /**
548  * security_compute_av - Compute access vector decisions.
549  * @ssid: source security identifier
550  * @tsid: target security identifier
551  * @tclass: target security class
552  * @requested: requested permissions
553  * @avd: access vector decisions
554  *
555  * Compute a set of access vector decisions based on the
556  * SID pair (@ssid, @tsid) for the permissions in @tclass.
557  * Return -%EINVAL if any of the parameters are invalid or %0
558  * if the access vector decisions were computed successfully.
559  */
560 int security_compute_av(u32 ssid,
561                         u32 tsid,
562                         u16 tclass,
563                         u32 requested,
564                         struct av_decision *avd)
565 {
566         struct context *scontext = NULL, *tcontext = NULL;
567         int rc = 0;
568
569         if (!ss_initialized) {
570                 avd->allowed = 0xffffffff;
571                 avd->decided = 0xffffffff;
572                 avd->auditallow = 0;
573                 avd->auditdeny = 0xffffffff;
574                 avd->seqno = latest_granting;
575                 return 0;
576         }
577
578         POLICY_RDLOCK;
579
580         scontext = sidtab_search(&sidtab, ssid);
581         if (!scontext) {
582                 printk(KERN_ERR "security_compute_av:  unrecognized SID %d\n",
583                        ssid);
584                 rc = -EINVAL;
585                 goto out;
586         }
587         tcontext = sidtab_search(&sidtab, tsid);
588         if (!tcontext) {
589                 printk(KERN_ERR "security_compute_av:  unrecognized SID %d\n",
590                        tsid);
591                 rc = -EINVAL;
592                 goto out;
593         }
594
595         rc = context_struct_compute_av(scontext, tcontext, tclass,
596                                        requested, avd);
597 out:
598         POLICY_RDUNLOCK;
599         return rc;
600 }
601
602 /*
603  * Write the security context string representation of
604  * the context structure `context' into a dynamically
605  * allocated string of the correct size.  Set `*scontext'
606  * to point to this string and set `*scontext_len' to
607  * the length of the string.
608  */
609 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
610 {
611         char *scontextp;
612
613         *scontext = NULL;
614         *scontext_len = 0;
615
616         /* Compute the size of the context. */
617         *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
618         *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
619         *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
620         *scontext_len += mls_compute_context_len(context);
621
622         /* Allocate space for the context; caller must free this space. */
623         scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
624         if (!scontextp) {
625                 return -ENOMEM;
626         }
627         *scontext = scontextp;
628
629         /*
630          * Copy the user name, role name and type name into the context.
631          */
632         sprintf(scontextp, "%s:%s:%s",
633                 policydb.p_user_val_to_name[context->user - 1],
634                 policydb.p_role_val_to_name[context->role - 1],
635                 policydb.p_type_val_to_name[context->type - 1]);
636         scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
637                      1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
638                      1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
639
640         mls_sid_to_context(context, &scontextp);
641
642         *scontextp = 0;
643
644         return 0;
645 }
646
647 #include "initial_sid_to_string.h"
648
649 const char *security_get_initial_sid_context(u32 sid)
650 {
651         if (unlikely(sid > SECINITSID_NUM))
652                 return NULL;
653         return initial_sid_to_string[sid];
654 }
655
656 /**
657  * security_sid_to_context - Obtain a context for a given SID.
658  * @sid: security identifier, SID
659  * @scontext: security context
660  * @scontext_len: length in bytes
661  *
662  * Write the string representation of the context associated with @sid
663  * into a dynamically allocated string of the correct size.  Set @scontext
664  * to point to this string and set @scontext_len to the length of the string.
665  */
666 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
667 {
668         struct context *context;
669         int rc = 0;
670
671         *scontext = NULL;
672         *scontext_len  = 0;
673
674         if (!ss_initialized) {
675                 if (sid <= SECINITSID_NUM) {
676                         char *scontextp;
677
678                         *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
679                         scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
680                         if (!scontextp) {
681                                 rc = -ENOMEM;
682                                 goto out;
683                         }
684                         strcpy(scontextp, initial_sid_to_string[sid]);
685                         *scontext = scontextp;
686                         goto out;
687                 }
688                 printk(KERN_ERR "security_sid_to_context:  called before initial "
689                        "load_policy on unknown SID %d\n", sid);
690                 rc = -EINVAL;
691                 goto out;
692         }
693         POLICY_RDLOCK;
694         context = sidtab_search(&sidtab, sid);
695         if (!context) {
696                 printk(KERN_ERR "security_sid_to_context:  unrecognized SID "
697                        "%d\n", sid);
698                 rc = -EINVAL;
699                 goto out_unlock;
700         }
701         rc = context_struct_to_string(context, scontext, scontext_len);
702 out_unlock:
703         POLICY_RDUNLOCK;
704 out:
705         return rc;
706
707 }
708
709 static int security_context_to_sid_core(char *scontext, u32 scontext_len,
710                                         u32 *sid, u32 def_sid, gfp_t gfp_flags)
711 {
712         char *scontext2;
713         struct context context;
714         struct role_datum *role;
715         struct type_datum *typdatum;
716         struct user_datum *usrdatum;
717         char *scontextp, *p, oldc;
718         int rc = 0;
719
720         if (!ss_initialized) {
721                 int i;
722
723                 for (i = 1; i < SECINITSID_NUM; i++) {
724                         if (!strcmp(initial_sid_to_string[i], scontext)) {
725                                 *sid = i;
726                                 goto out;
727                         }
728                 }
729                 *sid = SECINITSID_KERNEL;
730                 goto out;
731         }
732         *sid = SECSID_NULL;
733
734         /* Copy the string so that we can modify the copy as we parse it.
735            The string should already by null terminated, but we append a
736            null suffix to the copy to avoid problems with the existing
737            attr package, which doesn't view the null terminator as part
738            of the attribute value. */
739         scontext2 = kmalloc(scontext_len+1, gfp_flags);
740         if (!scontext2) {
741                 rc = -ENOMEM;
742                 goto out;
743         }
744         memcpy(scontext2, scontext, scontext_len);
745         scontext2[scontext_len] = 0;
746
747         context_init(&context);
748         *sid = SECSID_NULL;
749
750         POLICY_RDLOCK;
751
752         /* Parse the security context. */
753
754         rc = -EINVAL;
755         scontextp = (char *) scontext2;
756
757         /* Extract the user. */
758         p = scontextp;
759         while (*p && *p != ':')
760                 p++;
761
762         if (*p == 0)
763                 goto out_unlock;
764
765         *p++ = 0;
766
767         usrdatum = hashtab_search(policydb.p_users.table, scontextp);
768         if (!usrdatum)
769                 goto out_unlock;
770
771         context.user = usrdatum->value;
772
773         /* Extract role. */
774         scontextp = p;
775         while (*p && *p != ':')
776                 p++;
777
778         if (*p == 0)
779                 goto out_unlock;
780
781         *p++ = 0;
782
783         role = hashtab_search(policydb.p_roles.table, scontextp);
784         if (!role)
785                 goto out_unlock;
786         context.role = role->value;
787
788         /* Extract type. */
789         scontextp = p;
790         while (*p && *p != ':')
791                 p++;
792         oldc = *p;
793         *p++ = 0;
794
795         typdatum = hashtab_search(policydb.p_types.table, scontextp);
796         if (!typdatum)
797                 goto out_unlock;
798
799         context.type = typdatum->value;
800
801         rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
802         if (rc)
803                 goto out_unlock;
804
805         if ((p - scontext2) < scontext_len) {
806                 rc = -EINVAL;
807                 goto out_unlock;
808         }
809
810         /* Check the validity of the new context. */
811         if (!policydb_context_isvalid(&policydb, &context)) {
812                 rc = -EINVAL;
813                 goto out_unlock;
814         }
815         /* Obtain the new sid. */
816         rc = sidtab_context_to_sid(&sidtab, &context, sid);
817 out_unlock:
818         POLICY_RDUNLOCK;
819         context_destroy(&context);
820         kfree(scontext2);
821 out:
822         return rc;
823 }
824
825 /**
826  * security_context_to_sid - Obtain a SID for a given security context.
827  * @scontext: security context
828  * @scontext_len: length in bytes
829  * @sid: security identifier, SID
830  *
831  * Obtains a SID associated with the security context that
832  * has the string representation specified by @scontext.
833  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
834  * memory is available, or 0 on success.
835  */
836 int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
837 {
838         return security_context_to_sid_core(scontext, scontext_len,
839                                             sid, SECSID_NULL, GFP_KERNEL);
840 }
841
842 /**
843  * security_context_to_sid_default - Obtain a SID for a given security context,
844  * falling back to specified default if needed.
845  *
846  * @scontext: security context
847  * @scontext_len: length in bytes
848  * @sid: security identifier, SID
849  * @def_sid: default SID to assign on error
850  *
851  * Obtains a SID associated with the security context that
852  * has the string representation specified by @scontext.
853  * The default SID is passed to the MLS layer to be used to allow
854  * kernel labeling of the MLS field if the MLS field is not present
855  * (for upgrading to MLS without full relabel).
856  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
857  * memory is available, or 0 on success.
858  */
859 int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid,
860                                     u32 def_sid, gfp_t gfp_flags)
861 {
862         return security_context_to_sid_core(scontext, scontext_len,
863                                             sid, def_sid, gfp_flags);
864 }
865
866 static int compute_sid_handle_invalid_context(
867         struct context *scontext,
868         struct context *tcontext,
869         u16 tclass,
870         struct context *newcontext)
871 {
872         char *s = NULL, *t = NULL, *n = NULL;
873         u32 slen, tlen, nlen;
874
875         if (context_struct_to_string(scontext, &s, &slen) < 0)
876                 goto out;
877         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
878                 goto out;
879         if (context_struct_to_string(newcontext, &n, &nlen) < 0)
880                 goto out;
881         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
882                   "security_compute_sid:  invalid context %s"
883                   " for scontext=%s"
884                   " tcontext=%s"
885                   " tclass=%s",
886                   n, s, t, policydb.p_class_val_to_name[tclass-1]);
887 out:
888         kfree(s);
889         kfree(t);
890         kfree(n);
891         if (!selinux_enforcing)
892                 return 0;
893         return -EACCES;
894 }
895
896 static int security_compute_sid(u32 ssid,
897                                 u32 tsid,
898                                 u16 tclass,
899                                 u32 specified,
900                                 u32 *out_sid)
901 {
902         struct context *scontext = NULL, *tcontext = NULL, newcontext;
903         struct role_trans *roletr = NULL;
904         struct avtab_key avkey;
905         struct avtab_datum *avdatum;
906         struct avtab_node *node;
907         int rc = 0;
908
909         if (!ss_initialized) {
910                 switch (tclass) {
911                 case SECCLASS_PROCESS:
912                         *out_sid = ssid;
913                         break;
914                 default:
915                         *out_sid = tsid;
916                         break;
917                 }
918                 goto out;
919         }
920
921         context_init(&newcontext);
922
923         POLICY_RDLOCK;
924
925         scontext = sidtab_search(&sidtab, ssid);
926         if (!scontext) {
927                 printk(KERN_ERR "security_compute_sid:  unrecognized SID %d\n",
928                        ssid);
929                 rc = -EINVAL;
930                 goto out_unlock;
931         }
932         tcontext = sidtab_search(&sidtab, tsid);
933         if (!tcontext) {
934                 printk(KERN_ERR "security_compute_sid:  unrecognized SID %d\n",
935                        tsid);
936                 rc = -EINVAL;
937                 goto out_unlock;
938         }
939
940         /* Set the user identity. */
941         switch (specified) {
942         case AVTAB_TRANSITION:
943         case AVTAB_CHANGE:
944                 /* Use the process user identity. */
945                 newcontext.user = scontext->user;
946                 break;
947         case AVTAB_MEMBER:
948                 /* Use the related object owner. */
949                 newcontext.user = tcontext->user;
950                 break;
951         }
952
953         /* Set the role and type to default values. */
954         switch (tclass) {
955         case SECCLASS_PROCESS:
956                 /* Use the current role and type of process. */
957                 newcontext.role = scontext->role;
958                 newcontext.type = scontext->type;
959                 break;
960         default:
961                 /* Use the well-defined object role. */
962                 newcontext.role = OBJECT_R_VAL;
963                 /* Use the type of the related object. */
964                 newcontext.type = tcontext->type;
965         }
966
967         /* Look for a type transition/member/change rule. */
968         avkey.source_type = scontext->type;
969         avkey.target_type = tcontext->type;
970         avkey.target_class = tclass;
971         avkey.specified = specified;
972         avdatum = avtab_search(&policydb.te_avtab, &avkey);
973
974         /* If no permanent rule, also check for enabled conditional rules */
975         if(!avdatum) {
976                 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
977                 for (; node != NULL; node = avtab_search_node_next(node, specified)) {
978                         if (node->key.specified & AVTAB_ENABLED) {
979                                 avdatum = &node->datum;
980                                 break;
981                         }
982                 }
983         }
984
985         if (avdatum) {
986                 /* Use the type from the type transition/member/change rule. */
987                 newcontext.type = avdatum->data;
988         }
989
990         /* Check for class-specific changes. */
991         switch (tclass) {
992         case SECCLASS_PROCESS:
993                 if (specified & AVTAB_TRANSITION) {
994                         /* Look for a role transition rule. */
995                         for (roletr = policydb.role_tr; roletr;
996                              roletr = roletr->next) {
997                                 if (roletr->role == scontext->role &&
998                                     roletr->type == tcontext->type) {
999                                         /* Use the role transition rule. */
1000                                         newcontext.role = roletr->new_role;
1001                                         break;
1002                                 }
1003                         }
1004                 }
1005                 break;
1006         default:
1007                 break;
1008         }
1009
1010         /* Set the MLS attributes.
1011            This is done last because it may allocate memory. */
1012         rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
1013         if (rc)
1014                 goto out_unlock;
1015
1016         /* Check the validity of the context. */
1017         if (!policydb_context_isvalid(&policydb, &newcontext)) {
1018                 rc = compute_sid_handle_invalid_context(scontext,
1019                                                         tcontext,
1020                                                         tclass,
1021                                                         &newcontext);
1022                 if (rc)
1023                         goto out_unlock;
1024         }
1025         /* Obtain the sid for the context. */
1026         rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1027 out_unlock:
1028         POLICY_RDUNLOCK;
1029         context_destroy(&newcontext);
1030 out:
1031         return rc;
1032 }
1033
1034 /**
1035  * security_transition_sid - Compute the SID for a new subject/object.
1036  * @ssid: source security identifier
1037  * @tsid: target security identifier
1038  * @tclass: target security class
1039  * @out_sid: security identifier for new subject/object
1040  *
1041  * Compute a SID to use for labeling a new subject or object in the
1042  * class @tclass based on a SID pair (@ssid, @tsid).
1043  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1044  * if insufficient memory is available, or %0 if the new SID was
1045  * computed successfully.
1046  */
1047 int security_transition_sid(u32 ssid,
1048                             u32 tsid,
1049                             u16 tclass,
1050                             u32 *out_sid)
1051 {
1052         return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
1053 }
1054
1055 /**
1056  * security_member_sid - Compute the SID for member selection.
1057  * @ssid: source security identifier
1058  * @tsid: target security identifier
1059  * @tclass: target security class
1060  * @out_sid: security identifier for selected member
1061  *
1062  * Compute a SID to use when selecting a member of a polyinstantiated
1063  * object of class @tclass based on a SID pair (@ssid, @tsid).
1064  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1065  * if insufficient memory is available, or %0 if the SID was
1066  * computed successfully.
1067  */
1068 int security_member_sid(u32 ssid,
1069                         u32 tsid,
1070                         u16 tclass,
1071                         u32 *out_sid)
1072 {
1073         return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
1074 }
1075
1076 /**
1077  * security_change_sid - Compute the SID for object relabeling.
1078  * @ssid: source security identifier
1079  * @tsid: target security identifier
1080  * @tclass: target security class
1081  * @out_sid: security identifier for selected member
1082  *
1083  * Compute a SID to use for relabeling an object of class @tclass
1084  * based on a SID pair (@ssid, @tsid).
1085  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1086  * if insufficient memory is available, or %0 if the SID was
1087  * computed successfully.
1088  */
1089 int security_change_sid(u32 ssid,
1090                         u32 tsid,
1091                         u16 tclass,
1092                         u32 *out_sid)
1093 {
1094         return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
1095 }
1096
1097 /*
1098  * Verify that each kernel class that is defined in the
1099  * policy is correct
1100  */
1101 static int validate_classes(struct policydb *p)
1102 {
1103         int i, j;
1104         struct class_datum *cladatum;
1105         struct perm_datum *perdatum;
1106         u32 nprim, tmp, common_pts_len, perm_val, pol_val;
1107         u16 class_val;
1108         const struct selinux_class_perm *kdefs = &selinux_class_perm;
1109         const char *def_class, *def_perm, *pol_class;
1110         struct symtab *perms;
1111
1112         if (p->allow_unknown) {
1113                 u32 num_classes = kdefs->cts_len;
1114                 p->undefined_perms = kcalloc(num_classes, sizeof(u32), GFP_KERNEL);
1115                 if (!p->undefined_perms)
1116                         return -ENOMEM;
1117         }
1118
1119         for (i = 1; i < kdefs->cts_len; i++) {
1120                 def_class = kdefs->class_to_string[i];
1121                 if (!def_class)
1122                         continue;
1123                 if (i > p->p_classes.nprim) {
1124                         printk(KERN_INFO
1125                                "SELinux:  class %s not defined in policy\n",
1126                                def_class);
1127                         if (p->reject_unknown)
1128                                 return -EINVAL;
1129                         if (p->allow_unknown)
1130                                 p->undefined_perms[i-1] = ~0U;
1131                         continue;
1132                 }
1133                 pol_class = p->p_class_val_to_name[i-1];
1134                 if (strcmp(pol_class, def_class)) {
1135                         printk(KERN_ERR
1136                                "SELinux:  class %d is incorrect, found %s but should be %s\n",
1137                                i, pol_class, def_class);
1138                         return -EINVAL;
1139                 }
1140         }
1141         for (i = 0; i < kdefs->av_pts_len; i++) {
1142                 class_val = kdefs->av_perm_to_string[i].tclass;
1143                 perm_val = kdefs->av_perm_to_string[i].value;
1144                 def_perm = kdefs->av_perm_to_string[i].name;
1145                 if (class_val > p->p_classes.nprim)
1146                         continue;
1147                 pol_class = p->p_class_val_to_name[class_val-1];
1148                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1149                 BUG_ON(!cladatum);
1150                 perms = &cladatum->permissions;
1151                 nprim = 1 << (perms->nprim - 1);
1152                 if (perm_val > nprim) {
1153                         printk(KERN_INFO
1154                                "SELinux:  permission %s in class %s not defined in policy\n",
1155                                def_perm, pol_class);
1156                         if (p->reject_unknown)
1157                                 return -EINVAL;
1158                         if (p->allow_unknown)
1159                                 p->undefined_perms[class_val-1] |= perm_val;
1160                         continue;
1161                 }
1162                 perdatum = hashtab_search(perms->table, def_perm);
1163                 if (perdatum == NULL) {
1164                         printk(KERN_ERR
1165                                "SELinux:  permission %s in class %s not found in policy, bad policy\n",
1166                                def_perm, pol_class);
1167                         return -EINVAL;
1168                 }
1169                 pol_val = 1 << (perdatum->value - 1);
1170                 if (pol_val != perm_val) {
1171                         printk(KERN_ERR
1172                                "SELinux:  permission %s in class %s has incorrect value\n",
1173                                def_perm, pol_class);
1174                         return -EINVAL;
1175                 }
1176         }
1177         for (i = 0; i < kdefs->av_inherit_len; i++) {
1178                 class_val = kdefs->av_inherit[i].tclass;
1179                 if (class_val > p->p_classes.nprim)
1180                         continue;
1181                 pol_class = p->p_class_val_to_name[class_val-1];
1182                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1183                 BUG_ON(!cladatum);
1184                 if (!cladatum->comdatum) {
1185                         printk(KERN_ERR
1186                                "SELinux:  class %s should have an inherits clause but does not\n",
1187                                pol_class);
1188                         return -EINVAL;
1189                 }
1190                 tmp = kdefs->av_inherit[i].common_base;
1191                 common_pts_len = 0;
1192                 while (!(tmp & 0x01)) {
1193                         common_pts_len++;
1194                         tmp >>= 1;
1195                 }
1196                 perms = &cladatum->comdatum->permissions;
1197                 for (j = 0; j < common_pts_len; j++) {
1198                         def_perm = kdefs->av_inherit[i].common_pts[j];
1199                         if (j >= perms->nprim) {
1200                                 printk(KERN_INFO
1201                                        "SELinux:  permission %s in class %s not defined in policy\n",
1202                                        def_perm, pol_class);
1203                                 if (p->reject_unknown)
1204                                         return -EINVAL;
1205                                 if (p->allow_unknown)
1206                                         p->undefined_perms[class_val-1] |= (1 << j);
1207                                 continue;
1208                         }
1209                         perdatum = hashtab_search(perms->table, def_perm);
1210                         if (perdatum == NULL) {
1211                                 printk(KERN_ERR
1212                                        "SELinux:  permission %s in class %s not found in policy, bad policy\n",
1213                                        def_perm, pol_class);
1214                                 return -EINVAL;
1215                         }
1216                         if (perdatum->value != j + 1) {
1217                                 printk(KERN_ERR
1218                                        "SELinux:  permission %s in class %s has incorrect value\n",
1219                                        def_perm, pol_class);
1220                                 return -EINVAL;
1221                         }
1222                 }
1223         }
1224         return 0;
1225 }
1226
1227 /* Clone the SID into the new SID table. */
1228 static int clone_sid(u32 sid,
1229                      struct context *context,
1230                      void *arg)
1231 {
1232         struct sidtab *s = arg;
1233
1234         return sidtab_insert(s, sid, context);
1235 }
1236
1237 static inline int convert_context_handle_invalid_context(struct context *context)
1238 {
1239         int rc = 0;
1240
1241         if (selinux_enforcing) {
1242                 rc = -EINVAL;
1243         } else {
1244                 char *s;
1245                 u32 len;
1246
1247                 context_struct_to_string(context, &s, &len);
1248                 printk(KERN_ERR "SELinux:  context %s is invalid\n", s);
1249                 kfree(s);
1250         }
1251         return rc;
1252 }
1253
1254 struct convert_context_args {
1255         struct policydb *oldp;
1256         struct policydb *newp;
1257 };
1258
1259 /*
1260  * Convert the values in the security context
1261  * structure `c' from the values specified
1262  * in the policy `p->oldp' to the values specified
1263  * in the policy `p->newp'.  Verify that the
1264  * context is valid under the new policy.
1265  */
1266 static int convert_context(u32 key,
1267                            struct context *c,
1268                            void *p)
1269 {
1270         struct convert_context_args *args;
1271         struct context oldc;
1272         struct role_datum *role;
1273         struct type_datum *typdatum;
1274         struct user_datum *usrdatum;
1275         char *s;
1276         u32 len;
1277         int rc;
1278
1279         args = p;
1280
1281         rc = context_cpy(&oldc, c);
1282         if (rc)
1283                 goto out;
1284
1285         rc = -EINVAL;
1286
1287         /* Convert the user. */
1288         usrdatum = hashtab_search(args->newp->p_users.table,
1289                                   args->oldp->p_user_val_to_name[c->user - 1]);
1290         if (!usrdatum) {
1291                 goto bad;
1292         }
1293         c->user = usrdatum->value;
1294
1295         /* Convert the role. */
1296         role = hashtab_search(args->newp->p_roles.table,
1297                               args->oldp->p_role_val_to_name[c->role - 1]);
1298         if (!role) {
1299                 goto bad;
1300         }
1301         c->role = role->value;
1302
1303         /* Convert the type. */
1304         typdatum = hashtab_search(args->newp->p_types.table,
1305                                   args->oldp->p_type_val_to_name[c->type - 1]);
1306         if (!typdatum) {
1307                 goto bad;
1308         }
1309         c->type = typdatum->value;
1310
1311         rc = mls_convert_context(args->oldp, args->newp, c);
1312         if (rc)
1313                 goto bad;
1314
1315         /* Check the validity of the new context. */
1316         if (!policydb_context_isvalid(args->newp, c)) {
1317                 rc = convert_context_handle_invalid_context(&oldc);
1318                 if (rc)
1319                         goto bad;
1320         }
1321
1322         context_destroy(&oldc);
1323 out:
1324         return rc;
1325 bad:
1326         context_struct_to_string(&oldc, &s, &len);
1327         context_destroy(&oldc);
1328         printk(KERN_ERR "SELinux:  invalidating context %s\n", s);
1329         kfree(s);
1330         goto out;
1331 }
1332
1333 static void security_load_policycaps(void)
1334 {
1335         selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1336                                                   POLICYDB_CAPABILITY_NETPEER);
1337         selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1338                                                   POLICYDB_CAPABILITY_OPENPERM);
1339 }
1340
1341 extern void selinux_complete_init(void);
1342 static int security_preserve_bools(struct policydb *p);
1343
1344 /**
1345  * security_load_policy - Load a security policy configuration.
1346  * @data: binary policy data
1347  * @len: length of data in bytes
1348  *
1349  * Load a new set of security policy configuration data,
1350  * validate it and convert the SID table as necessary.
1351  * This function will flush the access vector cache after
1352  * loading the new policy.
1353  */
1354 int security_load_policy(void *data, size_t len)
1355 {
1356         struct policydb oldpolicydb, newpolicydb;
1357         struct sidtab oldsidtab, newsidtab;
1358         struct convert_context_args args;
1359         u32 seqno;
1360         int rc = 0;
1361         struct policy_file file = { data, len }, *fp = &file;
1362
1363         LOAD_LOCK;
1364
1365         if (!ss_initialized) {
1366                 avtab_cache_init();
1367                 if (policydb_read(&policydb, fp)) {
1368                         LOAD_UNLOCK;
1369                         avtab_cache_destroy();
1370                         return -EINVAL;
1371                 }
1372                 if (policydb_load_isids(&policydb, &sidtab)) {
1373                         LOAD_UNLOCK;
1374                         policydb_destroy(&policydb);
1375                         avtab_cache_destroy();
1376                         return -EINVAL;
1377                 }
1378                 /* Verify that the kernel defined classes are correct. */
1379                 if (validate_classes(&policydb)) {
1380                         printk(KERN_ERR
1381                                "SELinux:  the definition of a class is incorrect\n");
1382                         LOAD_UNLOCK;
1383                         sidtab_destroy(&sidtab);
1384                         policydb_destroy(&policydb);
1385                         avtab_cache_destroy();
1386                         return -EINVAL;
1387                 }
1388                 security_load_policycaps();
1389                 policydb_loaded_version = policydb.policyvers;
1390                 ss_initialized = 1;
1391                 seqno = ++latest_granting;
1392                 LOAD_UNLOCK;
1393                 selinux_complete_init();
1394                 avc_ss_reset(seqno);
1395                 selnl_notify_policyload(seqno);
1396                 selinux_netlbl_cache_invalidate();
1397                 selinux_xfrm_notify_policyload();
1398                 return 0;
1399         }
1400
1401 #if 0
1402         sidtab_hash_eval(&sidtab, "sids");
1403 #endif
1404
1405         if (policydb_read(&newpolicydb, fp)) {
1406                 LOAD_UNLOCK;
1407                 return -EINVAL;
1408         }
1409
1410         sidtab_init(&newsidtab);
1411
1412         /* Verify that the kernel defined classes are correct. */
1413         if (validate_classes(&newpolicydb)) {
1414                 printk(KERN_ERR
1415                        "SELinux:  the definition of a class is incorrect\n");
1416                 rc = -EINVAL;
1417                 goto err;
1418         }
1419
1420         rc = security_preserve_bools(&newpolicydb);
1421         if (rc) {
1422                 printk(KERN_ERR "SELinux:  unable to preserve booleans\n");
1423                 goto err;
1424         }
1425
1426         /* Clone the SID table. */
1427         sidtab_shutdown(&sidtab);
1428         if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
1429                 rc = -ENOMEM;
1430                 goto err;
1431         }
1432
1433         /* Convert the internal representations of contexts
1434            in the new SID table and remove invalid SIDs. */
1435         args.oldp = &policydb;
1436         args.newp = &newpolicydb;
1437         sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
1438
1439         /* Save the old policydb and SID table to free later. */
1440         memcpy(&oldpolicydb, &policydb, sizeof policydb);
1441         sidtab_set(&oldsidtab, &sidtab);
1442
1443         /* Install the new policydb and SID table. */
1444         POLICY_WRLOCK;
1445         memcpy(&policydb, &newpolicydb, sizeof policydb);
1446         sidtab_set(&sidtab, &newsidtab);
1447         security_load_policycaps();
1448         seqno = ++latest_granting;
1449         policydb_loaded_version = policydb.policyvers;
1450         POLICY_WRUNLOCK;
1451         LOAD_UNLOCK;
1452
1453         /* Free the old policydb and SID table. */
1454         policydb_destroy(&oldpolicydb);
1455         sidtab_destroy(&oldsidtab);
1456
1457         avc_ss_reset(seqno);
1458         selnl_notify_policyload(seqno);
1459         selinux_netlbl_cache_invalidate();
1460         selinux_xfrm_notify_policyload();
1461
1462         return 0;
1463
1464 err:
1465         LOAD_UNLOCK;
1466         sidtab_destroy(&newsidtab);
1467         policydb_destroy(&newpolicydb);
1468         return rc;
1469
1470 }
1471
1472 /**
1473  * security_port_sid - Obtain the SID for a port.
1474  * @domain: communication domain aka address family
1475  * @type: socket type
1476  * @protocol: protocol number
1477  * @port: port number
1478  * @out_sid: security identifier
1479  */
1480 int security_port_sid(u16 domain,
1481                       u16 type,
1482                       u8 protocol,
1483                       u16 port,
1484                       u32 *out_sid)
1485 {
1486         struct ocontext *c;
1487         int rc = 0;
1488
1489         POLICY_RDLOCK;
1490
1491         c = policydb.ocontexts[OCON_PORT];
1492         while (c) {
1493                 if (c->u.port.protocol == protocol &&
1494                     c->u.port.low_port <= port &&
1495                     c->u.port.high_port >= port)
1496                         break;
1497                 c = c->next;
1498         }
1499
1500         if (c) {
1501                 if (!c->sid[0]) {
1502                         rc = sidtab_context_to_sid(&sidtab,
1503                                                    &c->context[0],
1504                                                    &c->sid[0]);
1505                         if (rc)
1506                                 goto out;
1507                 }
1508                 *out_sid = c->sid[0];
1509         } else {
1510                 *out_sid = SECINITSID_PORT;
1511         }
1512
1513 out:
1514         POLICY_RDUNLOCK;
1515         return rc;
1516 }
1517
1518 /**
1519  * security_netif_sid - Obtain the SID for a network interface.
1520  * @name: interface name
1521  * @if_sid: interface SID
1522  */
1523 int security_netif_sid(char *name, u32 *if_sid)
1524 {
1525         int rc = 0;
1526         struct ocontext *c;
1527
1528         POLICY_RDLOCK;
1529
1530         c = policydb.ocontexts[OCON_NETIF];
1531         while (c) {
1532                 if (strcmp(name, c->u.name) == 0)
1533                         break;
1534                 c = c->next;
1535         }
1536
1537         if (c) {
1538                 if (!c->sid[0] || !c->sid[1]) {
1539                         rc = sidtab_context_to_sid(&sidtab,
1540                                                   &c->context[0],
1541                                                   &c->sid[0]);
1542                         if (rc)
1543                                 goto out;
1544                         rc = sidtab_context_to_sid(&sidtab,
1545                                                    &c->context[1],
1546                                                    &c->sid[1]);
1547                         if (rc)
1548                                 goto out;
1549                 }
1550                 *if_sid = c->sid[0];
1551         } else
1552                 *if_sid = SECINITSID_NETIF;
1553
1554 out:
1555         POLICY_RDUNLOCK;
1556         return rc;
1557 }
1558
1559 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1560 {
1561         int i, fail = 0;
1562
1563         for(i = 0; i < 4; i++)
1564                 if(addr[i] != (input[i] & mask[i])) {
1565                         fail = 1;
1566                         break;
1567                 }
1568
1569         return !fail;
1570 }
1571
1572 /**
1573  * security_node_sid - Obtain the SID for a node (host).
1574  * @domain: communication domain aka address family
1575  * @addrp: address
1576  * @addrlen: address length in bytes
1577  * @out_sid: security identifier
1578  */
1579 int security_node_sid(u16 domain,
1580                       void *addrp,
1581                       u32 addrlen,
1582                       u32 *out_sid)
1583 {
1584         int rc = 0;
1585         struct ocontext *c;
1586
1587         POLICY_RDLOCK;
1588
1589         switch (domain) {
1590         case AF_INET: {
1591                 u32 addr;
1592
1593                 if (addrlen != sizeof(u32)) {
1594                         rc = -EINVAL;
1595                         goto out;
1596                 }
1597
1598                 addr = *((u32 *)addrp);
1599
1600                 c = policydb.ocontexts[OCON_NODE];
1601                 while (c) {
1602                         if (c->u.node.addr == (addr & c->u.node.mask))
1603                                 break;
1604                         c = c->next;
1605                 }
1606                 break;
1607         }
1608
1609         case AF_INET6:
1610                 if (addrlen != sizeof(u64) * 2) {
1611                         rc = -EINVAL;
1612                         goto out;
1613                 }
1614                 c = policydb.ocontexts[OCON_NODE6];
1615                 while (c) {
1616                         if (match_ipv6_addrmask(addrp, c->u.node6.addr,
1617                                                 c->u.node6.mask))
1618                                 break;
1619                         c = c->next;
1620                 }
1621                 break;
1622
1623         default:
1624                 *out_sid = SECINITSID_NODE;
1625                 goto out;
1626         }
1627
1628         if (c) {
1629                 if (!c->sid[0]) {
1630                         rc = sidtab_context_to_sid(&sidtab,
1631                                                    &c->context[0],
1632                                                    &c->sid[0]);
1633                         if (rc)
1634                                 goto out;
1635                 }
1636                 *out_sid = c->sid[0];
1637         } else {
1638                 *out_sid = SECINITSID_NODE;
1639         }
1640
1641 out:
1642         POLICY_RDUNLOCK;
1643         return rc;
1644 }
1645
1646 #define SIDS_NEL 25
1647
1648 /**
1649  * security_get_user_sids - Obtain reachable SIDs for a user.
1650  * @fromsid: starting SID
1651  * @username: username
1652  * @sids: array of reachable SIDs for user
1653  * @nel: number of elements in @sids
1654  *
1655  * Generate the set of SIDs for legal security contexts
1656  * for a given user that can be reached by @fromsid.
1657  * Set *@sids to point to a dynamically allocated
1658  * array containing the set of SIDs.  Set *@nel to the
1659  * number of elements in the array.
1660  */
1661
1662 int security_get_user_sids(u32 fromsid,
1663                            char *username,
1664                            u32 **sids,
1665                            u32 *nel)
1666 {
1667         struct context *fromcon, usercon;
1668         u32 *mysids = NULL, *mysids2, sid;
1669         u32 mynel = 0, maxnel = SIDS_NEL;
1670         struct user_datum *user;
1671         struct role_datum *role;
1672         struct ebitmap_node *rnode, *tnode;
1673         int rc = 0, i, j;
1674
1675         *sids = NULL;
1676         *nel = 0;
1677
1678         if (!ss_initialized)
1679                 goto out;
1680
1681         POLICY_RDLOCK;
1682
1683         fromcon = sidtab_search(&sidtab, fromsid);
1684         if (!fromcon) {
1685                 rc = -EINVAL;
1686                 goto out_unlock;
1687         }
1688
1689         user = hashtab_search(policydb.p_users.table, username);
1690         if (!user) {
1691                 rc = -EINVAL;
1692                 goto out_unlock;
1693         }
1694         usercon.user = user->value;
1695
1696         mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
1697         if (!mysids) {
1698                 rc = -ENOMEM;
1699                 goto out_unlock;
1700         }
1701
1702         ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
1703                 role = policydb.role_val_to_struct[i];
1704                 usercon.role = i+1;
1705                 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
1706                         usercon.type = j+1;
1707
1708                         if (mls_setup_user_range(fromcon, user, &usercon))
1709                                 continue;
1710
1711                         rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
1712                         if (rc)
1713                                 goto out_unlock;
1714                         if (mynel < maxnel) {
1715                                 mysids[mynel++] = sid;
1716                         } else {
1717                                 maxnel += SIDS_NEL;
1718                                 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
1719                                 if (!mysids2) {
1720                                         rc = -ENOMEM;
1721                                         goto out_unlock;
1722                                 }
1723                                 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
1724                                 kfree(mysids);
1725                                 mysids = mysids2;
1726                                 mysids[mynel++] = sid;
1727                         }
1728                 }
1729         }
1730
1731 out_unlock:
1732         POLICY_RDUNLOCK;
1733         if (rc || !mynel) {
1734                 kfree(mysids);
1735                 goto out;
1736         }
1737
1738         mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
1739         if (!mysids2) {
1740                 rc = -ENOMEM;
1741                 kfree(mysids);
1742                 goto out;
1743         }
1744         for (i = 0, j = 0; i < mynel; i++) {
1745                 rc = avc_has_perm_noaudit(fromsid, mysids[i],
1746                                           SECCLASS_PROCESS,
1747                                           PROCESS__TRANSITION, AVC_STRICT,
1748                                           NULL);
1749                 if (!rc)
1750                         mysids2[j++] = mysids[i];
1751                 cond_resched();
1752         }
1753         rc = 0;
1754         kfree(mysids);
1755         *sids = mysids2;
1756         *nel = j;
1757 out:
1758         return rc;
1759 }
1760
1761 /**
1762  * security_genfs_sid - Obtain a SID for a file in a filesystem
1763  * @fstype: filesystem type
1764  * @path: path from root of mount
1765  * @sclass: file security class
1766  * @sid: SID for path
1767  *
1768  * Obtain a SID to use for a file in a filesystem that
1769  * cannot support xattr or use a fixed labeling behavior like
1770  * transition SIDs or task SIDs.
1771  */
1772 int security_genfs_sid(const char *fstype,
1773                        char *path,
1774                        u16 sclass,
1775                        u32 *sid)
1776 {
1777         int len;
1778         struct genfs *genfs;
1779         struct ocontext *c;
1780         int rc = 0, cmp = 0;
1781
1782         while (path[0] == '/' && path[1] == '/')
1783                 path++;
1784
1785         POLICY_RDLOCK;
1786
1787         for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
1788                 cmp = strcmp(fstype, genfs->fstype);
1789                 if (cmp <= 0)
1790                         break;
1791         }
1792
1793         if (!genfs || cmp) {
1794                 *sid = SECINITSID_UNLABELED;
1795                 rc = -ENOENT;
1796                 goto out;
1797         }
1798
1799         for (c = genfs->head; c; c = c->next) {
1800                 len = strlen(c->u.name);
1801                 if ((!c->v.sclass || sclass == c->v.sclass) &&
1802                     (strncmp(c->u.name, path, len) == 0))
1803                         break;
1804         }
1805
1806         if (!c) {
1807                 *sid = SECINITSID_UNLABELED;
1808                 rc = -ENOENT;
1809                 goto out;
1810         }
1811
1812         if (!c->sid[0]) {
1813                 rc = sidtab_context_to_sid(&sidtab,
1814                                            &c->context[0],
1815                                            &c->sid[0]);
1816                 if (rc)
1817                         goto out;
1818         }
1819
1820         *sid = c->sid[0];
1821 out:
1822         POLICY_RDUNLOCK;
1823         return rc;
1824 }
1825
1826 /**
1827  * security_fs_use - Determine how to handle labeling for a filesystem.
1828  * @fstype: filesystem type
1829  * @behavior: labeling behavior
1830  * @sid: SID for filesystem (superblock)
1831  */
1832 int security_fs_use(
1833         const char *fstype,
1834         unsigned int *behavior,
1835         u32 *sid)
1836 {
1837         int rc = 0;
1838         struct ocontext *c;
1839
1840         POLICY_RDLOCK;
1841
1842         c = policydb.ocontexts[OCON_FSUSE];
1843         while (c) {
1844                 if (strcmp(fstype, c->u.name) == 0)
1845                         break;
1846                 c = c->next;
1847         }
1848
1849         if (c) {
1850                 *behavior = c->v.behavior;
1851                 if (!c->sid[0]) {
1852                         rc = sidtab_context_to_sid(&sidtab,
1853                                                    &c->context[0],
1854                                                    &c->sid[0]);
1855                         if (rc)
1856                                 goto out;
1857                 }
1858                 *sid = c->sid[0];
1859         } else {
1860                 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
1861                 if (rc) {
1862                         *behavior = SECURITY_FS_USE_NONE;
1863                         rc = 0;
1864                 } else {
1865                         *behavior = SECURITY_FS_USE_GENFS;
1866                 }
1867         }
1868
1869 out:
1870         POLICY_RDUNLOCK;
1871         return rc;
1872 }
1873
1874 int security_get_bools(int *len, char ***names, int **values)
1875 {
1876         int i, rc = -ENOMEM;
1877
1878         POLICY_RDLOCK;
1879         *names = NULL;
1880         *values = NULL;
1881
1882         *len = policydb.p_bools.nprim;
1883         if (!*len) {
1884                 rc = 0;
1885                 goto out;
1886         }
1887
1888        *names = kcalloc(*len, sizeof(char*), GFP_ATOMIC);
1889         if (!*names)
1890                 goto err;
1891
1892        *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
1893         if (!*values)
1894                 goto err;
1895
1896         for (i = 0; i < *len; i++) {
1897                 size_t name_len;
1898                 (*values)[i] = policydb.bool_val_to_struct[i]->state;
1899                 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
1900                (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
1901                 if (!(*names)[i])
1902                         goto err;
1903                 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
1904                 (*names)[i][name_len - 1] = 0;
1905         }
1906         rc = 0;
1907 out:
1908         POLICY_RDUNLOCK;
1909         return rc;
1910 err:
1911         if (*names) {
1912                 for (i = 0; i < *len; i++)
1913                         kfree((*names)[i]);
1914         }
1915         kfree(*values);
1916         goto out;
1917 }
1918
1919
1920 int security_set_bools(int len, int *values)
1921 {
1922         int i, rc = 0;
1923         int lenp, seqno = 0;
1924         struct cond_node *cur;
1925
1926         POLICY_WRLOCK;
1927
1928         lenp = policydb.p_bools.nprim;
1929         if (len != lenp) {
1930                 rc = -EFAULT;
1931                 goto out;
1932         }
1933
1934         for (i = 0; i < len; i++) {
1935                 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
1936                         audit_log(current->audit_context, GFP_ATOMIC,
1937                                 AUDIT_MAC_CONFIG_CHANGE,
1938                                 "bool=%s val=%d old_val=%d auid=%u ses=%u",
1939                                 policydb.p_bool_val_to_name[i],
1940                                 !!values[i],
1941                                 policydb.bool_val_to_struct[i]->state,
1942                                 audit_get_loginuid(current),
1943                                 audit_get_sessionid(current));
1944                 }
1945                 if (values[i]) {
1946                         policydb.bool_val_to_struct[i]->state = 1;
1947                 } else {
1948                         policydb.bool_val_to_struct[i]->state = 0;
1949                 }
1950         }
1951
1952         for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
1953                 rc = evaluate_cond_node(&policydb, cur);
1954                 if (rc)
1955                         goto out;
1956         }
1957
1958         seqno = ++latest_granting;
1959
1960 out:
1961         POLICY_WRUNLOCK;
1962         if (!rc) {
1963                 avc_ss_reset(seqno);
1964                 selnl_notify_policyload(seqno);
1965                 selinux_xfrm_notify_policyload();
1966         }
1967         return rc;
1968 }
1969
1970 int security_get_bool_value(int bool)
1971 {
1972         int rc = 0;
1973         int len;
1974
1975         POLICY_RDLOCK;
1976
1977         len = policydb.p_bools.nprim;
1978         if (bool >= len) {
1979                 rc = -EFAULT;
1980                 goto out;
1981         }
1982
1983         rc = policydb.bool_val_to_struct[bool]->state;
1984 out:
1985         POLICY_RDUNLOCK;
1986         return rc;
1987 }
1988
1989 static int security_preserve_bools(struct policydb *p)
1990 {
1991         int rc, nbools = 0, *bvalues = NULL, i;
1992         char **bnames = NULL;
1993         struct cond_bool_datum *booldatum;
1994         struct cond_node *cur;
1995
1996         rc = security_get_bools(&nbools, &bnames, &bvalues);
1997         if (rc)
1998                 goto out;
1999         for (i = 0; i < nbools; i++) {
2000                 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2001                 if (booldatum)
2002                         booldatum->state = bvalues[i];
2003         }
2004         for (cur = p->cond_list; cur != NULL; cur = cur->next) {
2005                 rc = evaluate_cond_node(p, cur);
2006                 if (rc)
2007                         goto out;
2008         }
2009
2010 out:
2011         if (bnames) {
2012                 for (i = 0; i < nbools; i++)
2013                         kfree(bnames[i]);
2014         }
2015         kfree(bnames);
2016         kfree(bvalues);
2017         return rc;
2018 }
2019
2020 /*
2021  * security_sid_mls_copy() - computes a new sid based on the given
2022  * sid and the mls portion of mls_sid.
2023  */
2024 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2025 {
2026         struct context *context1;
2027         struct context *context2;
2028         struct context newcon;
2029         char *s;
2030         u32 len;
2031         int rc = 0;
2032
2033         if (!ss_initialized || !selinux_mls_enabled) {
2034                 *new_sid = sid;
2035                 goto out;
2036         }
2037
2038         context_init(&newcon);
2039
2040         POLICY_RDLOCK;
2041         context1 = sidtab_search(&sidtab, sid);
2042         if (!context1) {
2043                 printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
2044                        "%d\n", sid);
2045                 rc = -EINVAL;
2046                 goto out_unlock;
2047         }
2048
2049         context2 = sidtab_search(&sidtab, mls_sid);
2050         if (!context2) {
2051                 printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
2052                        "%d\n", mls_sid);
2053                 rc = -EINVAL;
2054                 goto out_unlock;
2055         }
2056
2057         newcon.user = context1->user;
2058         newcon.role = context1->role;
2059         newcon.type = context1->type;
2060         rc = mls_context_cpy(&newcon, context2);
2061         if (rc)
2062                 goto out_unlock;
2063
2064         /* Check the validity of the new context. */
2065         if (!policydb_context_isvalid(&policydb, &newcon)) {
2066                 rc = convert_context_handle_invalid_context(&newcon);
2067                 if (rc)
2068                         goto bad;
2069         }
2070
2071         rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2072         goto out_unlock;
2073
2074 bad:
2075         if (!context_struct_to_string(&newcon, &s, &len)) {
2076                 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2077                           "security_sid_mls_copy: invalid context %s", s);
2078                 kfree(s);
2079         }
2080
2081 out_unlock:
2082         POLICY_RDUNLOCK;
2083         context_destroy(&newcon);
2084 out:
2085         return rc;
2086 }
2087
2088 /**
2089  * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2090  * @nlbl_sid: NetLabel SID
2091  * @nlbl_type: NetLabel labeling protocol type
2092  * @xfrm_sid: XFRM SID
2093  *
2094  * Description:
2095  * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2096  * resolved into a single SID it is returned via @peer_sid and the function
2097  * returns zero.  Otherwise @peer_sid is set to SECSID_NULL and the function
2098  * returns a negative value.  A table summarizing the behavior is below:
2099  *
2100  *                                 | function return |      @sid
2101  *   ------------------------------+-----------------+-----------------
2102  *   no peer labels                |        0        |    SECSID_NULL
2103  *   single peer label             |        0        |    <peer_label>
2104  *   multiple, consistent labels   |        0        |    <peer_label>
2105  *   multiple, inconsistent labels |    -<errno>     |    SECSID_NULL
2106  *
2107  */
2108 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2109                                  u32 xfrm_sid,
2110                                  u32 *peer_sid)
2111 {
2112         int rc;
2113         struct context *nlbl_ctx;
2114         struct context *xfrm_ctx;
2115
2116         /* handle the common (which also happens to be the set of easy) cases
2117          * right away, these two if statements catch everything involving a
2118          * single or absent peer SID/label */
2119         if (xfrm_sid == SECSID_NULL) {
2120                 *peer_sid = nlbl_sid;
2121                 return 0;
2122         }
2123         /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2124          * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2125          * is present */
2126         if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2127                 *peer_sid = xfrm_sid;
2128                 return 0;
2129         }
2130
2131         /* we don't need to check ss_initialized here since the only way both
2132          * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2133          * security server was initialized and ss_initialized was true */
2134         if (!selinux_mls_enabled) {
2135                 *peer_sid = SECSID_NULL;
2136                 return 0;
2137         }
2138
2139         POLICY_RDLOCK;
2140
2141         nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2142         if (!nlbl_ctx) {
2143                 printk(KERN_ERR
2144                        "security_sid_mls_cmp:  unrecognized SID %d\n",
2145                        nlbl_sid);
2146                 rc = -EINVAL;
2147                 goto out_slowpath;
2148         }
2149         xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2150         if (!xfrm_ctx) {
2151                 printk(KERN_ERR
2152                        "security_sid_mls_cmp:  unrecognized SID %d\n",
2153                        xfrm_sid);
2154                 rc = -EINVAL;
2155                 goto out_slowpath;
2156         }
2157         rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2158
2159 out_slowpath:
2160         POLICY_RDUNLOCK;
2161         if (rc == 0)
2162                 /* at present NetLabel SIDs/labels really only carry MLS
2163                  * information so if the MLS portion of the NetLabel SID
2164                  * matches the MLS portion of the labeled XFRM SID/label
2165                  * then pass along the XFRM SID as it is the most
2166                  * expressive */
2167                 *peer_sid = xfrm_sid;
2168         else
2169                 *peer_sid = SECSID_NULL;
2170         return rc;
2171 }
2172
2173 static int get_classes_callback(void *k, void *d, void *args)
2174 {
2175         struct class_datum *datum = d;
2176         char *name = k, **classes = args;
2177         int value = datum->value - 1;
2178
2179         classes[value] = kstrdup(name, GFP_ATOMIC);
2180         if (!classes[value])
2181                 return -ENOMEM;
2182
2183         return 0;
2184 }
2185
2186 int security_get_classes(char ***classes, int *nclasses)
2187 {
2188         int rc = -ENOMEM;
2189
2190         POLICY_RDLOCK;
2191
2192         *nclasses = policydb.p_classes.nprim;
2193         *classes = kcalloc(*nclasses, sizeof(*classes), GFP_ATOMIC);
2194         if (!*classes)
2195                 goto out;
2196
2197         rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2198                         *classes);
2199         if (rc < 0) {
2200                 int i;
2201                 for (i = 0; i < *nclasses; i++)
2202                         kfree((*classes)[i]);
2203                 kfree(*classes);
2204         }
2205
2206 out:
2207         POLICY_RDUNLOCK;
2208         return rc;
2209 }
2210
2211 static int get_permissions_callback(void *k, void *d, void *args)
2212 {
2213         struct perm_datum *datum = d;
2214         char *name = k, **perms = args;
2215         int value = datum->value - 1;
2216
2217         perms[value] = kstrdup(name, GFP_ATOMIC);
2218         if (!perms[value])
2219                 return -ENOMEM;
2220
2221         return 0;
2222 }
2223
2224 int security_get_permissions(char *class, char ***perms, int *nperms)
2225 {
2226         int rc = -ENOMEM, i;
2227         struct class_datum *match;
2228
2229         POLICY_RDLOCK;
2230
2231         match = hashtab_search(policydb.p_classes.table, class);
2232         if (!match) {
2233                 printk(KERN_ERR "%s:  unrecognized class %s\n",
2234                         __func__, class);
2235                 rc = -EINVAL;
2236                 goto out;
2237         }
2238
2239         *nperms = match->permissions.nprim;
2240         *perms = kcalloc(*nperms, sizeof(*perms), GFP_ATOMIC);
2241         if (!*perms)
2242                 goto out;
2243
2244         if (match->comdatum) {
2245                 rc = hashtab_map(match->comdatum->permissions.table,
2246                                 get_permissions_callback, *perms);
2247                 if (rc < 0)
2248                         goto err;
2249         }
2250
2251         rc = hashtab_map(match->permissions.table, get_permissions_callback,
2252                         *perms);
2253         if (rc < 0)
2254                 goto err;
2255
2256 out:
2257         POLICY_RDUNLOCK;
2258         return rc;
2259
2260 err:
2261         POLICY_RDUNLOCK;
2262         for (i = 0; i < *nperms; i++)
2263                 kfree((*perms)[i]);
2264         kfree(*perms);
2265         return rc;
2266 }
2267
2268 int security_get_reject_unknown(void)
2269 {
2270         return policydb.reject_unknown;
2271 }
2272
2273 int security_get_allow_unknown(void)
2274 {
2275         return policydb.allow_unknown;
2276 }
2277
2278 /**
2279  * security_policycap_supported - Check for a specific policy capability
2280  * @req_cap: capability
2281  *
2282  * Description:
2283  * This function queries the currently loaded policy to see if it supports the
2284  * capability specified by @req_cap.  Returns true (1) if the capability is
2285  * supported, false (0) if it isn't supported.
2286  *
2287  */
2288 int security_policycap_supported(unsigned int req_cap)
2289 {
2290         int rc;
2291
2292         POLICY_RDLOCK;
2293         rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2294         POLICY_RDUNLOCK;
2295
2296         return rc;
2297 }
2298
2299 struct selinux_audit_rule {
2300         u32 au_seqno;
2301         struct context au_ctxt;
2302 };
2303
2304 void selinux_audit_rule_free(struct selinux_audit_rule *rule)
2305 {
2306         if (rule) {
2307                 context_destroy(&rule->au_ctxt);
2308                 kfree(rule);
2309         }
2310 }
2311
2312 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr,
2313                             struct selinux_audit_rule **rule)
2314 {
2315         struct selinux_audit_rule *tmprule;
2316         struct role_datum *roledatum;
2317         struct type_datum *typedatum;
2318         struct user_datum *userdatum;
2319         int rc = 0;
2320
2321         *rule = NULL;
2322
2323         if (!ss_initialized)
2324                 return -EOPNOTSUPP;
2325
2326         switch (field) {
2327         case AUDIT_SUBJ_USER:
2328         case AUDIT_SUBJ_ROLE:
2329         case AUDIT_SUBJ_TYPE:
2330         case AUDIT_OBJ_USER:
2331         case AUDIT_OBJ_ROLE:
2332         case AUDIT_OBJ_TYPE:
2333                 /* only 'equals' and 'not equals' fit user, role, and type */
2334                 if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
2335                         return -EINVAL;
2336                 break;
2337         case AUDIT_SUBJ_SEN:
2338         case AUDIT_SUBJ_CLR:
2339         case AUDIT_OBJ_LEV_LOW:
2340         case AUDIT_OBJ_LEV_HIGH:
2341                 /* we do not allow a range, indicated by the presense of '-' */
2342                 if (strchr(rulestr, '-'))
2343                         return -EINVAL;
2344                 break;
2345         default:
2346                 /* only the above fields are valid */
2347                 return -EINVAL;
2348         }
2349
2350         tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2351         if (!tmprule)
2352                 return -ENOMEM;
2353
2354         context_init(&tmprule->au_ctxt);
2355
2356         POLICY_RDLOCK;
2357
2358         tmprule->au_seqno = latest_granting;
2359
2360         switch (field) {
2361         case AUDIT_SUBJ_USER:
2362         case AUDIT_OBJ_USER:
2363                 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2364                 if (!userdatum)
2365                         rc = -EINVAL;
2366                 else
2367                         tmprule->au_ctxt.user = userdatum->value;
2368                 break;
2369         case AUDIT_SUBJ_ROLE:
2370         case AUDIT_OBJ_ROLE:
2371                 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2372                 if (!roledatum)
2373                         rc = -EINVAL;
2374                 else
2375                         tmprule->au_ctxt.role = roledatum->value;
2376                 break;
2377         case AUDIT_SUBJ_TYPE:
2378         case AUDIT_OBJ_TYPE:
2379                 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2380                 if (!typedatum)
2381                         rc = -EINVAL;
2382                 else
2383                         tmprule->au_ctxt.type = typedatum->value;
2384                 break;
2385         case AUDIT_SUBJ_SEN:
2386         case AUDIT_SUBJ_CLR:
2387         case AUDIT_OBJ_LEV_LOW:
2388         case AUDIT_OBJ_LEV_HIGH:
2389                 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2390                 break;
2391         }
2392
2393         POLICY_RDUNLOCK;
2394
2395         if (rc) {
2396                 selinux_audit_rule_free(tmprule);
2397                 tmprule = NULL;
2398         }
2399
2400         *rule = tmprule;
2401
2402         return rc;
2403 }
2404
2405 int selinux_audit_rule_match(u32 sid, u32 field, u32 op,
2406                              struct selinux_audit_rule *rule,
2407                              struct audit_context *actx)
2408 {
2409         struct context *ctxt;
2410         struct mls_level *level;
2411         int match = 0;
2412
2413         if (!rule) {
2414                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2415                           "selinux_audit_rule_match: missing rule\n");
2416                 return -ENOENT;
2417         }
2418
2419         POLICY_RDLOCK;
2420
2421         if (rule->au_seqno < latest_granting) {
2422                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2423                           "selinux_audit_rule_match: stale rule\n");
2424                 match = -ESTALE;
2425                 goto out;
2426         }
2427
2428         ctxt = sidtab_search(&sidtab, sid);
2429         if (!ctxt) {
2430                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2431                           "selinux_audit_rule_match: unrecognized SID %d\n",
2432                           sid);
2433                 match = -ENOENT;
2434                 goto out;
2435         }
2436
2437         /* a field/op pair that is not caught here will simply fall through
2438            without a match */
2439         switch (field) {
2440         case AUDIT_SUBJ_USER:
2441         case AUDIT_OBJ_USER:
2442                 switch (op) {
2443                 case AUDIT_EQUAL:
2444                         match = (ctxt->user == rule->au_ctxt.user);
2445                         break;
2446                 case AUDIT_NOT_EQUAL:
2447                         match = (ctxt->user != rule->au_ctxt.user);
2448                         break;
2449                 }
2450                 break;
2451         case AUDIT_SUBJ_ROLE:
2452         case AUDIT_OBJ_ROLE:
2453                 switch (op) {
2454                 case AUDIT_EQUAL:
2455                         match = (ctxt->role == rule->au_ctxt.role);
2456                         break;
2457                 case AUDIT_NOT_EQUAL:
2458                         match = (ctxt->role != rule->au_ctxt.role);
2459                         break;
2460                 }
2461                 break;
2462         case AUDIT_SUBJ_TYPE:
2463         case AUDIT_OBJ_TYPE:
2464                 switch (op) {
2465                 case AUDIT_EQUAL:
2466                         match = (ctxt->type == rule->au_ctxt.type);
2467                         break;
2468                 case AUDIT_NOT_EQUAL:
2469                         match = (ctxt->type != rule->au_ctxt.type);
2470                         break;
2471                 }
2472                 break;
2473         case AUDIT_SUBJ_SEN:
2474         case AUDIT_SUBJ_CLR:
2475         case AUDIT_OBJ_LEV_LOW:
2476         case AUDIT_OBJ_LEV_HIGH:
2477                 level = ((field == AUDIT_SUBJ_SEN ||
2478                           field == AUDIT_OBJ_LEV_LOW) ?
2479                          &ctxt->range.level[0] : &ctxt->range.level[1]);
2480                 switch (op) {
2481                 case AUDIT_EQUAL:
2482                         match = mls_level_eq(&rule->au_ctxt.range.level[0],
2483                                              level);
2484                         break;
2485                 case AUDIT_NOT_EQUAL:
2486                         match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2487                                               level);
2488                         break;
2489                 case AUDIT_LESS_THAN:
2490                         match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2491                                                level) &&
2492                                  !mls_level_eq(&rule->au_ctxt.range.level[0],
2493                                                level));
2494                         break;
2495                 case AUDIT_LESS_THAN_OR_EQUAL:
2496                         match = mls_level_dom(&rule->au_ctxt.range.level[0],
2497                                               level);
2498                         break;
2499                 case AUDIT_GREATER_THAN:
2500                         match = (mls_level_dom(level,
2501                                               &rule->au_ctxt.range.level[0]) &&
2502                                  !mls_level_eq(level,
2503                                                &rule->au_ctxt.range.level[0]));
2504                         break;
2505                 case AUDIT_GREATER_THAN_OR_EQUAL:
2506                         match = mls_level_dom(level,
2507                                               &rule->au_ctxt.range.level[0]);
2508                         break;
2509                 }
2510         }
2511
2512 out:
2513         POLICY_RDUNLOCK;
2514         return match;
2515 }
2516
2517 static int (*aurule_callback)(void) = NULL;
2518
2519 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
2520                                u16 class, u32 perms, u32 *retained)
2521 {
2522         int err = 0;
2523
2524         if (event == AVC_CALLBACK_RESET && aurule_callback)
2525                 err = aurule_callback();
2526         return err;
2527 }
2528
2529 static int __init aurule_init(void)
2530 {
2531         int err;
2532
2533         err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
2534                                SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
2535         if (err)
2536                 panic("avc_add_callback() failed, error %d\n", err);
2537
2538         return err;
2539 }
2540 __initcall(aurule_init);
2541
2542 void selinux_audit_set_callback(int (*callback)(void))
2543 {
2544         aurule_callback = callback;
2545 }
2546
2547 #ifdef CONFIG_NETLABEL
2548 /**
2549  * security_netlbl_cache_add - Add an entry to the NetLabel cache
2550  * @secattr: the NetLabel packet security attributes
2551  * @sid: the SELinux SID
2552  *
2553  * Description:
2554  * Attempt to cache the context in @ctx, which was derived from the packet in
2555  * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
2556  * already been initialized.
2557  *
2558  */
2559 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
2560                                       u32 sid)
2561 {
2562         u32 *sid_cache;
2563
2564         sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
2565         if (sid_cache == NULL)
2566                 return;
2567         secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
2568         if (secattr->cache == NULL) {
2569                 kfree(sid_cache);
2570                 return;
2571         }
2572
2573         *sid_cache = sid;
2574         secattr->cache->free = kfree;
2575         secattr->cache->data = sid_cache;
2576         secattr->flags |= NETLBL_SECATTR_CACHE;
2577 }
2578
2579 /**
2580  * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
2581  * @secattr: the NetLabel packet security attributes
2582  * @sid: the SELinux SID
2583  *
2584  * Description:
2585  * Convert the given NetLabel security attributes in @secattr into a
2586  * SELinux SID.  If the @secattr field does not contain a full SELinux
2587  * SID/context then use SECINITSID_NETMSG as the foundation.  If possibile the
2588  * 'cache' field of @secattr is set and the CACHE flag is set; this is to
2589  * allow the @secattr to be used by NetLabel to cache the secattr to SID
2590  * conversion for future lookups.  Returns zero on success, negative values on
2591  * failure.
2592  *
2593  */
2594 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
2595                                    u32 *sid)
2596 {
2597         int rc = -EIDRM;
2598         struct context *ctx;
2599         struct context ctx_new;
2600
2601         if (!ss_initialized) {
2602                 *sid = SECSID_NULL;
2603                 return 0;
2604         }
2605
2606         POLICY_RDLOCK;
2607
2608         if (secattr->flags & NETLBL_SECATTR_CACHE) {
2609                 *sid = *(u32 *)secattr->cache->data;
2610                 rc = 0;
2611         } else if (secattr->flags & NETLBL_SECATTR_SECID) {
2612                 *sid = secattr->attr.secid;
2613                 rc = 0;
2614         } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
2615                 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
2616                 if (ctx == NULL)
2617                         goto netlbl_secattr_to_sid_return;
2618
2619                 ctx_new.user = ctx->user;
2620                 ctx_new.role = ctx->role;
2621                 ctx_new.type = ctx->type;
2622                 mls_import_netlbl_lvl(&ctx_new, secattr);
2623                 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
2624                         if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
2625                                                   secattr->attr.mls.cat) != 0)
2626                                 goto netlbl_secattr_to_sid_return;
2627                         ctx_new.range.level[1].cat.highbit =
2628                                 ctx_new.range.level[0].cat.highbit;
2629                         ctx_new.range.level[1].cat.node =
2630                                 ctx_new.range.level[0].cat.node;
2631                 } else {
2632                         ebitmap_init(&ctx_new.range.level[0].cat);
2633                         ebitmap_init(&ctx_new.range.level[1].cat);
2634                 }
2635                 if (mls_context_isvalid(&policydb, &ctx_new) != 1)
2636                         goto netlbl_secattr_to_sid_return_cleanup;
2637
2638                 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2639                 if (rc != 0)
2640                         goto netlbl_secattr_to_sid_return_cleanup;
2641
2642                 security_netlbl_cache_add(secattr, *sid);
2643
2644                 ebitmap_destroy(&ctx_new.range.level[0].cat);
2645         } else {
2646                 *sid = SECSID_NULL;
2647                 rc = 0;
2648         }
2649
2650 netlbl_secattr_to_sid_return:
2651         POLICY_RDUNLOCK;
2652         return rc;
2653 netlbl_secattr_to_sid_return_cleanup:
2654         ebitmap_destroy(&ctx_new.range.level[0].cat);
2655         goto netlbl_secattr_to_sid_return;
2656 }
2657
2658 /**
2659  * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
2660  * @sid: the SELinux SID
2661  * @secattr: the NetLabel packet security attributes
2662  *
2663  * Description:
2664  * Convert the given SELinux SID in @sid into a NetLabel security attribute.
2665  * Returns zero on success, negative values on failure.
2666  *
2667  */
2668 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
2669 {
2670         int rc = -ENOENT;
2671         struct context *ctx;
2672
2673         if (!ss_initialized)
2674                 return 0;
2675
2676         POLICY_RDLOCK;
2677         ctx = sidtab_search(&sidtab, sid);
2678         if (ctx == NULL)
2679                 goto netlbl_sid_to_secattr_failure;
2680         secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
2681                                   GFP_ATOMIC);
2682         secattr->flags |= NETLBL_SECATTR_DOMAIN;
2683         mls_export_netlbl_lvl(ctx, secattr);
2684         rc = mls_export_netlbl_cat(ctx, secattr);
2685         if (rc != 0)
2686                 goto netlbl_sid_to_secattr_failure;
2687         POLICY_RDUNLOCK;
2688
2689         return 0;
2690
2691 netlbl_sid_to_secattr_failure:
2692         POLICY_RDUNLOCK;
2693         return rc;
2694 }
2695 #endif /* CONFIG_NETLABEL */