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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@paul-moore.com>
17 *
18 * Added support for NetLabel
19 * Added support for the policy capability bitmap
20 *
21 * Updated: Chad Sellers <csellers@tresys.com>
22 *
23 * Added validation of kernel classes and permissions
24 *
25 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
26 *
27 * Added support for bounds domain and audit messaged on masked permissions
28 *
29 * Updated: Guido Trentalancia <guido@trentalancia.com>
30 *
31 * Added support for runtime switching of the policy type
32 *
33 * Copyright (C) 2008, 2009 NEC Corporation
34 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
35 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
36 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
37 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
38 * This program is free software; you can redistribute it and/or modify
39 * it under the terms of the GNU General Public License as published by
40 * the Free Software Foundation, version 2.
41 */
42#include <linux/kernel.h>
43#include <linux/slab.h>
44#include <linux/string.h>
45#include <linux/spinlock.h>
46#include <linux/rcupdate.h>
47#include <linux/errno.h>
48#include <linux/in.h>
49#include <linux/sched.h>
50#include <linux/audit.h>
51#include <linux/mutex.h>
52#include <linux/selinux.h>
53#include <linux/flex_array.h>
54#include <linux/vmalloc.h>
55#include <net/netlabel.h>
56
57#include "flask.h"
58#include "avc.h"
59#include "avc_ss.h"
60#include "security.h"
61#include "context.h"
62#include "policydb.h"
63#include "sidtab.h"
64#include "services.h"
65#include "conditional.h"
66#include "mls.h"
67#include "objsec.h"
68#include "netlabel.h"
69#include "xfrm.h"
70#include "ebitmap.h"
71#include "audit.h"
72
73extern void selnl_notify_policyload(u32 seqno);
74
75int selinux_policycap_netpeer;
76int selinux_policycap_openperm;
77
78static DEFINE_RWLOCK(policy_rwlock);
79
80static struct sidtab sidtab;
81struct policydb policydb;
82int ss_initialized;
83
84/*
85 * The largest sequence number that has been used when
86 * providing an access decision to the access vector cache.
87 * The sequence number only changes when a policy change
88 * occurs.
89 */
90static u32 latest_granting;
91
92/* Forward declaration. */
93static int context_struct_to_string(struct context *context, char **scontext,
94 u32 *scontext_len);
95
96static void context_struct_compute_av(struct context *scontext,
97 struct context *tcontext,
98 u16 tclass,
99 struct av_decision *avd);
100
101struct selinux_mapping {
102 u16 value; /* policy value */
103 unsigned num_perms;
104 u32 perms[sizeof(u32) * 8];
105};
106
107static struct selinux_mapping *current_mapping;
108static u16 current_mapping_size;
109
110static int selinux_set_mapping(struct policydb *pol,
111 struct security_class_mapping *map,
112 struct selinux_mapping **out_map_p,
113 u16 *out_map_size)
114{
115 struct selinux_mapping *out_map = NULL;
116 size_t size = sizeof(struct selinux_mapping);
117 u16 i, j;
118 unsigned k;
119 bool print_unknown_handle = false;
120
121 /* Find number of classes in the input mapping */
122 if (!map)
123 return -EINVAL;
124 i = 0;
125 while (map[i].name)
126 i++;
127
128 /* Allocate space for the class records, plus one for class zero */
129 out_map = kcalloc(++i, size, GFP_ATOMIC);
130 if (!out_map)
131 return -ENOMEM;
132
133 /* Store the raw class and permission values */
134 j = 0;
135 while (map[j].name) {
136 struct security_class_mapping *p_in = map + (j++);
137 struct selinux_mapping *p_out = out_map + j;
138
139 /* An empty class string skips ahead */
140 if (!strcmp(p_in->name, "")) {
141 p_out->num_perms = 0;
142 continue;
143 }
144
145 p_out->value = string_to_security_class(pol, p_in->name);
146 if (!p_out->value) {
147 printk(KERN_INFO
148 "SELinux: Class %s not defined in policy.\n",
149 p_in->name);
150 if (pol->reject_unknown)
151 goto err;
152 p_out->num_perms = 0;
153 print_unknown_handle = true;
154 continue;
155 }
156
157 k = 0;
158 while (p_in->perms && p_in->perms[k]) {
159 /* An empty permission string skips ahead */
160 if (!*p_in->perms[k]) {
161 k++;
162 continue;
163 }
164 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
165 p_in->perms[k]);
166 if (!p_out->perms[k]) {
167 printk(KERN_INFO
168 "SELinux: Permission %s in class %s not defined in policy.\n",
169 p_in->perms[k], p_in->name);
170 if (pol->reject_unknown)
171 goto err;
172 print_unknown_handle = true;
173 }
174
175 k++;
176 }
177 p_out->num_perms = k;
178 }
179
180 if (print_unknown_handle)
181 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
182 pol->allow_unknown ? "allowed" : "denied");
183
184 *out_map_p = out_map;
185 *out_map_size = i;
186 return 0;
187err:
188 kfree(out_map);
189 return -EINVAL;
190}
191
192/*
193 * Get real, policy values from mapped values
194 */
195
196static u16 unmap_class(u16 tclass)
197{
198 if (tclass < current_mapping_size)
199 return current_mapping[tclass].value;
200
201 return tclass;
202}
203
204/*
205 * Get kernel value for class from its policy value
206 */
207static u16 map_class(u16 pol_value)
208{
209 u16 i;
210
211 for (i = 1; i < current_mapping_size; i++) {
212 if (current_mapping[i].value == pol_value)
213 return i;
214 }
215
216 return SECCLASS_NULL;
217}
218
219static void map_decision(u16 tclass, struct av_decision *avd,
220 int allow_unknown)
221{
222 if (tclass < current_mapping_size) {
223 unsigned i, n = current_mapping[tclass].num_perms;
224 u32 result;
225
226 for (i = 0, result = 0; i < n; i++) {
227 if (avd->allowed & current_mapping[tclass].perms[i])
228 result |= 1<<i;
229 if (allow_unknown && !current_mapping[tclass].perms[i])
230 result |= 1<<i;
231 }
232 avd->allowed = result;
233
234 for (i = 0, result = 0; i < n; i++)
235 if (avd->auditallow & current_mapping[tclass].perms[i])
236 result |= 1<<i;
237 avd->auditallow = result;
238
239 for (i = 0, result = 0; i < n; i++) {
240 if (avd->auditdeny & current_mapping[tclass].perms[i])
241 result |= 1<<i;
242 if (!allow_unknown && !current_mapping[tclass].perms[i])
243 result |= 1<<i;
244 }
245 /*
246 * In case the kernel has a bug and requests a permission
247 * between num_perms and the maximum permission number, we
248 * should audit that denial
249 */
250 for (; i < (sizeof(u32)*8); i++)
251 result |= 1<<i;
252 avd->auditdeny = result;
253 }
254}
255
256int security_mls_enabled(void)
257{
258 return policydb.mls_enabled;
259}
260
261/*
262 * Return the boolean value of a constraint expression
263 * when it is applied to the specified source and target
264 * security contexts.
265 *
266 * xcontext is a special beast... It is used by the validatetrans rules
267 * only. For these rules, scontext is the context before the transition,
268 * tcontext is the context after the transition, and xcontext is the context
269 * of the process performing the transition. All other callers of
270 * constraint_expr_eval should pass in NULL for xcontext.
271 */
272static int constraint_expr_eval(struct context *scontext,
273 struct context *tcontext,
274 struct context *xcontext,
275 struct constraint_expr *cexpr)
276{
277 u32 val1, val2;
278 struct context *c;
279 struct role_datum *r1, *r2;
280 struct mls_level *l1, *l2;
281 struct constraint_expr *e;
282 int s[CEXPR_MAXDEPTH];
283 int sp = -1;
284
285 for (e = cexpr; e; e = e->next) {
286 switch (e->expr_type) {
287 case CEXPR_NOT:
288 BUG_ON(sp < 0);
289 s[sp] = !s[sp];
290 break;
291 case CEXPR_AND:
292 BUG_ON(sp < 1);
293 sp--;
294 s[sp] &= s[sp + 1];
295 break;
296 case CEXPR_OR:
297 BUG_ON(sp < 1);
298 sp--;
299 s[sp] |= s[sp + 1];
300 break;
301 case CEXPR_ATTR:
302 if (sp == (CEXPR_MAXDEPTH - 1))
303 return 0;
304 switch (e->attr) {
305 case CEXPR_USER:
306 val1 = scontext->user;
307 val2 = tcontext->user;
308 break;
309 case CEXPR_TYPE:
310 val1 = scontext->type;
311 val2 = tcontext->type;
312 break;
313 case CEXPR_ROLE:
314 val1 = scontext->role;
315 val2 = tcontext->role;
316 r1 = policydb.role_val_to_struct[val1 - 1];
317 r2 = policydb.role_val_to_struct[val2 - 1];
318 switch (e->op) {
319 case CEXPR_DOM:
320 s[++sp] = ebitmap_get_bit(&r1->dominates,
321 val2 - 1);
322 continue;
323 case CEXPR_DOMBY:
324 s[++sp] = ebitmap_get_bit(&r2->dominates,
325 val1 - 1);
326 continue;
327 case CEXPR_INCOMP:
328 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
329 val2 - 1) &&
330 !ebitmap_get_bit(&r2->dominates,
331 val1 - 1));
332 continue;
333 default:
334 break;
335 }
336 break;
337 case CEXPR_L1L2:
338 l1 = &(scontext->range.level[0]);
339 l2 = &(tcontext->range.level[0]);
340 goto mls_ops;
341 case CEXPR_L1H2:
342 l1 = &(scontext->range.level[0]);
343 l2 = &(tcontext->range.level[1]);
344 goto mls_ops;
345 case CEXPR_H1L2:
346 l1 = &(scontext->range.level[1]);
347 l2 = &(tcontext->range.level[0]);
348 goto mls_ops;
349 case CEXPR_H1H2:
350 l1 = &(scontext->range.level[1]);
351 l2 = &(tcontext->range.level[1]);
352 goto mls_ops;
353 case CEXPR_L1H1:
354 l1 = &(scontext->range.level[0]);
355 l2 = &(scontext->range.level[1]);
356 goto mls_ops;
357 case CEXPR_L2H2:
358 l1 = &(tcontext->range.level[0]);
359 l2 = &(tcontext->range.level[1]);
360 goto mls_ops;
361mls_ops:
362 switch (e->op) {
363 case CEXPR_EQ:
364 s[++sp] = mls_level_eq(l1, l2);
365 continue;
366 case CEXPR_NEQ:
367 s[++sp] = !mls_level_eq(l1, l2);
368 continue;
369 case CEXPR_DOM:
370 s[++sp] = mls_level_dom(l1, l2);
371 continue;
372 case CEXPR_DOMBY:
373 s[++sp] = mls_level_dom(l2, l1);
374 continue;
375 case CEXPR_INCOMP:
376 s[++sp] = mls_level_incomp(l2, l1);
377 continue;
378 default:
379 BUG();
380 return 0;
381 }
382 break;
383 default:
384 BUG();
385 return 0;
386 }
387
388 switch (e->op) {
389 case CEXPR_EQ:
390 s[++sp] = (val1 == val2);
391 break;
392 case CEXPR_NEQ:
393 s[++sp] = (val1 != val2);
394 break;
395 default:
396 BUG();
397 return 0;
398 }
399 break;
400 case CEXPR_NAMES:
401 if (sp == (CEXPR_MAXDEPTH-1))
402 return 0;
403 c = scontext;
404 if (e->attr & CEXPR_TARGET)
405 c = tcontext;
406 else if (e->attr & CEXPR_XTARGET) {
407 c = xcontext;
408 if (!c) {
409 BUG();
410 return 0;
411 }
412 }
413 if (e->attr & CEXPR_USER)
414 val1 = c->user;
415 else if (e->attr & CEXPR_ROLE)
416 val1 = c->role;
417 else if (e->attr & CEXPR_TYPE)
418 val1 = c->type;
419 else {
420 BUG();
421 return 0;
422 }
423
424 switch (e->op) {
425 case CEXPR_EQ:
426 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
427 break;
428 case CEXPR_NEQ:
429 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
430 break;
431 default:
432 BUG();
433 return 0;
434 }
435 break;
436 default:
437 BUG();
438 return 0;
439 }
440 }
441
442 BUG_ON(sp != 0);
443 return s[0];
444}
445
446/*
447 * security_dump_masked_av - dumps masked permissions during
448 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
449 */
450static int dump_masked_av_helper(void *k, void *d, void *args)
451{
452 struct perm_datum *pdatum = d;
453 char **permission_names = args;
454
455 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
456
457 permission_names[pdatum->value - 1] = (char *)k;
458
459 return 0;
460}
461
462static void security_dump_masked_av(struct context *scontext,
463 struct context *tcontext,
464 u16 tclass,
465 u32 permissions,
466 const char *reason)
467{
468 struct common_datum *common_dat;
469 struct class_datum *tclass_dat;
470 struct audit_buffer *ab;
471 char *tclass_name;
472 char *scontext_name = NULL;
473 char *tcontext_name = NULL;
474 char *permission_names[32];
475 int index;
476 u32 length;
477 bool need_comma = false;
478
479 if (!permissions)
480 return;
481
482 tclass_name = sym_name(&policydb, SYM_CLASSES, tclass - 1);
483 tclass_dat = policydb.class_val_to_struct[tclass - 1];
484 common_dat = tclass_dat->comdatum;
485
486 /* init permission_names */
487 if (common_dat &&
488 hashtab_map(common_dat->permissions.table,
489 dump_masked_av_helper, permission_names) < 0)
490 goto out;
491
492 if (hashtab_map(tclass_dat->permissions.table,
493 dump_masked_av_helper, permission_names) < 0)
494 goto out;
495
496 /* get scontext/tcontext in text form */
497 if (context_struct_to_string(scontext,
498 &scontext_name, &length) < 0)
499 goto out;
500
501 if (context_struct_to_string(tcontext,
502 &tcontext_name, &length) < 0)
503 goto out;
504
505 /* audit a message */
506 ab = audit_log_start(current->audit_context,
507 GFP_ATOMIC, AUDIT_SELINUX_ERR);
508 if (!ab)
509 goto out;
510
511 audit_log_format(ab, "op=security_compute_av reason=%s "
512 "scontext=%s tcontext=%s tclass=%s perms=",
513 reason, scontext_name, tcontext_name, tclass_name);
514
515 for (index = 0; index < 32; index++) {
516 u32 mask = (1 << index);
517
518 if ((mask & permissions) == 0)
519 continue;
520
521 audit_log_format(ab, "%s%s",
522 need_comma ? "," : "",
523 permission_names[index]
524 ? permission_names[index] : "????");
525 need_comma = true;
526 }
527 audit_log_end(ab);
528out:
529 /* release scontext/tcontext */
530 kfree(tcontext_name);
531 kfree(scontext_name);
532
533 return;
534}
535
536/*
537 * security_boundary_permission - drops violated permissions
538 * on boundary constraint.
539 */
540static void type_attribute_bounds_av(struct context *scontext,
541 struct context *tcontext,
542 u16 tclass,
543 struct av_decision *avd)
544{
545 struct context lo_scontext;
546 struct context lo_tcontext;
547 struct av_decision lo_avd;
548 struct type_datum *source;
549 struct type_datum *target;
550 u32 masked = 0;
551
552 source = flex_array_get_ptr(policydb.type_val_to_struct_array,
553 scontext->type - 1);
554 BUG_ON(!source);
555
556 target = flex_array_get_ptr(policydb.type_val_to_struct_array,
557 tcontext->type - 1);
558 BUG_ON(!target);
559
560 if (source->bounds) {
561 memset(&lo_avd, 0, sizeof(lo_avd));
562
563 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
564 lo_scontext.type = source->bounds;
565
566 context_struct_compute_av(&lo_scontext,
567 tcontext,
568 tclass,
569 &lo_avd);
570 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
571 return; /* no masked permission */
572 masked = ~lo_avd.allowed & avd->allowed;
573 }
574
575 if (target->bounds) {
576 memset(&lo_avd, 0, sizeof(lo_avd));
577
578 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
579 lo_tcontext.type = target->bounds;
580
581 context_struct_compute_av(scontext,
582 &lo_tcontext,
583 tclass,
584 &lo_avd);
585 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
586 return; /* no masked permission */
587 masked = ~lo_avd.allowed & avd->allowed;
588 }
589
590 if (source->bounds && target->bounds) {
591 memset(&lo_avd, 0, sizeof(lo_avd));
592 /*
593 * lo_scontext and lo_tcontext are already
594 * set up.
595 */
596
597 context_struct_compute_av(&lo_scontext,
598 &lo_tcontext,
599 tclass,
600 &lo_avd);
601 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
602 return; /* no masked permission */
603 masked = ~lo_avd.allowed & avd->allowed;
604 }
605
606 if (masked) {
607 /* mask violated permissions */
608 avd->allowed &= ~masked;
609
610 /* audit masked permissions */
611 security_dump_masked_av(scontext, tcontext,
612 tclass, masked, "bounds");
613 }
614}
615
616/*
617 * Compute access vectors based on a context structure pair for
618 * the permissions in a particular class.
619 */
620static void context_struct_compute_av(struct context *scontext,
621 struct context *tcontext,
622 u16 tclass,
623 struct av_decision *avd)
624{
625 struct constraint_node *constraint;
626 struct role_allow *ra;
627 struct avtab_key avkey;
628 struct avtab_node *node;
629 struct class_datum *tclass_datum;
630 struct ebitmap *sattr, *tattr;
631 struct ebitmap_node *snode, *tnode;
632 unsigned int i, j;
633
634 avd->allowed = 0;
635 avd->auditallow = 0;
636 avd->auditdeny = 0xffffffff;
637
638 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
639 if (printk_ratelimit())
640 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass);
641 return;
642 }
643
644 tclass_datum = policydb.class_val_to_struct[tclass - 1];
645
646 /*
647 * If a specific type enforcement rule was defined for
648 * this permission check, then use it.
649 */
650 avkey.target_class = tclass;
651 avkey.specified = AVTAB_AV;
652 sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1);
653 BUG_ON(!sattr);
654 tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1);
655 BUG_ON(!tattr);
656 ebitmap_for_each_positive_bit(sattr, snode, i) {
657 ebitmap_for_each_positive_bit(tattr, tnode, j) {
658 avkey.source_type = i + 1;
659 avkey.target_type = j + 1;
660 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
661 node;
662 node = avtab_search_node_next(node, avkey.specified)) {
663 if (node->key.specified == AVTAB_ALLOWED)
664 avd->allowed |= node->datum.data;
665 else if (node->key.specified == AVTAB_AUDITALLOW)
666 avd->auditallow |= node->datum.data;
667 else if (node->key.specified == AVTAB_AUDITDENY)
668 avd->auditdeny &= node->datum.data;
669 }
670
671 /* Check conditional av table for additional permissions */
672 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
673
674 }
675 }
676
677 /*
678 * Remove any permissions prohibited by a constraint (this includes
679 * the MLS policy).
680 */
681 constraint = tclass_datum->constraints;
682 while (constraint) {
683 if ((constraint->permissions & (avd->allowed)) &&
684 !constraint_expr_eval(scontext, tcontext, NULL,
685 constraint->expr)) {
686 avd->allowed &= ~(constraint->permissions);
687 }
688 constraint = constraint->next;
689 }
690
691 /*
692 * If checking process transition permission and the
693 * role is changing, then check the (current_role, new_role)
694 * pair.
695 */
696 if (tclass == policydb.process_class &&
697 (avd->allowed & policydb.process_trans_perms) &&
698 scontext->role != tcontext->role) {
699 for (ra = policydb.role_allow; ra; ra = ra->next) {
700 if (scontext->role == ra->role &&
701 tcontext->role == ra->new_role)
702 break;
703 }
704 if (!ra)
705 avd->allowed &= ~policydb.process_trans_perms;
706 }
707
708 /*
709 * If the given source and target types have boundary
710 * constraint, lazy checks have to mask any violated
711 * permission and notice it to userspace via audit.
712 */
713 type_attribute_bounds_av(scontext, tcontext,
714 tclass, avd);
715}
716
717static int security_validtrans_handle_fail(struct context *ocontext,
718 struct context *ncontext,
719 struct context *tcontext,
720 u16 tclass)
721{
722 char *o = NULL, *n = NULL, *t = NULL;
723 u32 olen, nlen, tlen;
724
725 if (context_struct_to_string(ocontext, &o, &olen))
726 goto out;
727 if (context_struct_to_string(ncontext, &n, &nlen))
728 goto out;
729 if (context_struct_to_string(tcontext, &t, &tlen))
730 goto out;
731 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
732 "security_validate_transition: denied for"
733 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
734 o, n, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
735out:
736 kfree(o);
737 kfree(n);
738 kfree(t);
739
740 if (!selinux_enforcing)
741 return 0;
742 return -EPERM;
743}
744
745int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
746 u16 orig_tclass)
747{
748 struct context *ocontext;
749 struct context *ncontext;
750 struct context *tcontext;
751 struct class_datum *tclass_datum;
752 struct constraint_node *constraint;
753 u16 tclass;
754 int rc = 0;
755
756 if (!ss_initialized)
757 return 0;
758
759 read_lock(&policy_rwlock);
760
761 tclass = unmap_class(orig_tclass);
762
763 if (!tclass || tclass > policydb.p_classes.nprim) {
764 printk(KERN_ERR "SELinux: %s: unrecognized class %d\n",
765 __func__, tclass);
766 rc = -EINVAL;
767 goto out;
768 }
769 tclass_datum = policydb.class_val_to_struct[tclass - 1];
770
771 ocontext = sidtab_search(&sidtab, oldsid);
772 if (!ocontext) {
773 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
774 __func__, oldsid);
775 rc = -EINVAL;
776 goto out;
777 }
778
779 ncontext = sidtab_search(&sidtab, newsid);
780 if (!ncontext) {
781 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
782 __func__, newsid);
783 rc = -EINVAL;
784 goto out;
785 }
786
787 tcontext = sidtab_search(&sidtab, tasksid);
788 if (!tcontext) {
789 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
790 __func__, tasksid);
791 rc = -EINVAL;
792 goto out;
793 }
794
795 constraint = tclass_datum->validatetrans;
796 while (constraint) {
797 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
798 constraint->expr)) {
799 rc = security_validtrans_handle_fail(ocontext, ncontext,
800 tcontext, tclass);
801 goto out;
802 }
803 constraint = constraint->next;
804 }
805
806out:
807 read_unlock(&policy_rwlock);
808 return rc;
809}
810
811/*
812 * security_bounded_transition - check whether the given
813 * transition is directed to bounded, or not.
814 * It returns 0, if @newsid is bounded by @oldsid.
815 * Otherwise, it returns error code.
816 *
817 * @oldsid : current security identifier
818 * @newsid : destinated security identifier
819 */
820int security_bounded_transition(u32 old_sid, u32 new_sid)
821{
822 struct context *old_context, *new_context;
823 struct type_datum *type;
824 int index;
825 int rc;
826
827 read_lock(&policy_rwlock);
828
829 rc = -EINVAL;
830 old_context = sidtab_search(&sidtab, old_sid);
831 if (!old_context) {
832 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
833 __func__, old_sid);
834 goto out;
835 }
836
837 rc = -EINVAL;
838 new_context = sidtab_search(&sidtab, new_sid);
839 if (!new_context) {
840 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
841 __func__, new_sid);
842 goto out;
843 }
844
845 rc = 0;
846 /* type/domain unchanged */
847 if (old_context->type == new_context->type)
848 goto out;
849
850 index = new_context->type;
851 while (true) {
852 type = flex_array_get_ptr(policydb.type_val_to_struct_array,
853 index - 1);
854 BUG_ON(!type);
855
856 /* not bounded anymore */
857 rc = -EPERM;
858 if (!type->bounds)
859 break;
860
861 /* @newsid is bounded by @oldsid */
862 rc = 0;
863 if (type->bounds == old_context->type)
864 break;
865
866 index = type->bounds;
867 }
868
869 if (rc) {
870 char *old_name = NULL;
871 char *new_name = NULL;
872 u32 length;
873
874 if (!context_struct_to_string(old_context,
875 &old_name, &length) &&
876 !context_struct_to_string(new_context,
877 &new_name, &length)) {
878 audit_log(current->audit_context,
879 GFP_ATOMIC, AUDIT_SELINUX_ERR,
880 "op=security_bounded_transition "
881 "result=denied "
882 "oldcontext=%s newcontext=%s",
883 old_name, new_name);
884 }
885 kfree(new_name);
886 kfree(old_name);
887 }
888out:
889 read_unlock(&policy_rwlock);
890
891 return rc;
892}
893
894static void avd_init(struct av_decision *avd)
895{
896 avd->allowed = 0;
897 avd->auditallow = 0;
898 avd->auditdeny = 0xffffffff;
899 avd->seqno = latest_granting;
900 avd->flags = 0;
901}
902
903
904/**
905 * security_compute_av - Compute access vector decisions.
906 * @ssid: source security identifier
907 * @tsid: target security identifier
908 * @tclass: target security class
909 * @avd: access vector decisions
910 *
911 * Compute a set of access vector decisions based on the
912 * SID pair (@ssid, @tsid) for the permissions in @tclass.
913 */
914void security_compute_av(u32 ssid,
915 u32 tsid,
916 u16 orig_tclass,
917 struct av_decision *avd)
918{
919 u16 tclass;
920 struct context *scontext = NULL, *tcontext = NULL;
921
922 read_lock(&policy_rwlock);
923 avd_init(avd);
924 if (!ss_initialized)
925 goto allow;
926
927 scontext = sidtab_search(&sidtab, ssid);
928 if (!scontext) {
929 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
930 __func__, ssid);
931 goto out;
932 }
933
934 /* permissive domain? */
935 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
936 avd->flags |= AVD_FLAGS_PERMISSIVE;
937
938 tcontext = sidtab_search(&sidtab, tsid);
939 if (!tcontext) {
940 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
941 __func__, tsid);
942 goto out;
943 }
944
945 tclass = unmap_class(orig_tclass);
946 if (unlikely(orig_tclass && !tclass)) {
947 if (policydb.allow_unknown)
948 goto allow;
949 goto out;
950 }
951 context_struct_compute_av(scontext, tcontext, tclass, avd);
952 map_decision(orig_tclass, avd, policydb.allow_unknown);
953out:
954 read_unlock(&policy_rwlock);
955 return;
956allow:
957 avd->allowed = 0xffffffff;
958 goto out;
959}
960
961void security_compute_av_user(u32 ssid,
962 u32 tsid,
963 u16 tclass,
964 struct av_decision *avd)
965{
966 struct context *scontext = NULL, *tcontext = NULL;
967
968 read_lock(&policy_rwlock);
969 avd_init(avd);
970 if (!ss_initialized)
971 goto allow;
972
973 scontext = sidtab_search(&sidtab, ssid);
974 if (!scontext) {
975 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
976 __func__, ssid);
977 goto out;
978 }
979
980 /* permissive domain? */
981 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
982 avd->flags |= AVD_FLAGS_PERMISSIVE;
983
984 tcontext = sidtab_search(&sidtab, tsid);
985 if (!tcontext) {
986 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
987 __func__, tsid);
988 goto out;
989 }
990
991 if (unlikely(!tclass)) {
992 if (policydb.allow_unknown)
993 goto allow;
994 goto out;
995 }
996
997 context_struct_compute_av(scontext, tcontext, tclass, avd);
998 out:
999 read_unlock(&policy_rwlock);
1000 return;
1001allow:
1002 avd->allowed = 0xffffffff;
1003 goto out;
1004}
1005
1006/*
1007 * Write the security context string representation of
1008 * the context structure `context' into a dynamically
1009 * allocated string of the correct size. Set `*scontext'
1010 * to point to this string and set `*scontext_len' to
1011 * the length of the string.
1012 */
1013static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
1014{
1015 char *scontextp;
1016
1017 if (scontext)
1018 *scontext = NULL;
1019 *scontext_len = 0;
1020
1021 if (context->len) {
1022 *scontext_len = context->len;
1023 *scontext = kstrdup(context->str, GFP_ATOMIC);
1024 if (!(*scontext))
1025 return -ENOMEM;
1026 return 0;
1027 }
1028
1029 /* Compute the size of the context. */
1030 *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1;
1031 *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1;
1032 *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1;
1033 *scontext_len += mls_compute_context_len(context);
1034
1035 if (!scontext)
1036 return 0;
1037
1038 /* Allocate space for the context; caller must free this space. */
1039 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1040 if (!scontextp)
1041 return -ENOMEM;
1042 *scontext = scontextp;
1043
1044 /*
1045 * Copy the user name, role name and type name into the context.
1046 */
1047 sprintf(scontextp, "%s:%s:%s",
1048 sym_name(&policydb, SYM_USERS, context->user - 1),
1049 sym_name(&policydb, SYM_ROLES, context->role - 1),
1050 sym_name(&policydb, SYM_TYPES, context->type - 1));
1051 scontextp += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) +
1052 1 + strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) +
1053 1 + strlen(sym_name(&policydb, SYM_TYPES, context->type - 1));
1054
1055 mls_sid_to_context(context, &scontextp);
1056
1057 *scontextp = 0;
1058
1059 return 0;
1060}
1061
1062#include "initial_sid_to_string.h"
1063
1064const char *security_get_initial_sid_context(u32 sid)
1065{
1066 if (unlikely(sid > SECINITSID_NUM))
1067 return NULL;
1068 return initial_sid_to_string[sid];
1069}
1070
1071static int security_sid_to_context_core(u32 sid, char **scontext,
1072 u32 *scontext_len, int force)
1073{
1074 struct context *context;
1075 int rc = 0;
1076
1077 if (scontext)
1078 *scontext = NULL;
1079 *scontext_len = 0;
1080
1081 if (!ss_initialized) {
1082 if (sid <= SECINITSID_NUM) {
1083 char *scontextp;
1084
1085 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1086 if (!scontext)
1087 goto out;
1088 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1089 if (!scontextp) {
1090 rc = -ENOMEM;
1091 goto out;
1092 }
1093 strcpy(scontextp, initial_sid_to_string[sid]);
1094 *scontext = scontextp;
1095 goto out;
1096 }
1097 printk(KERN_ERR "SELinux: %s: called before initial "
1098 "load_policy on unknown SID %d\n", __func__, sid);
1099 rc = -EINVAL;
1100 goto out;
1101 }
1102 read_lock(&policy_rwlock);
1103 if (force)
1104 context = sidtab_search_force(&sidtab, sid);
1105 else
1106 context = sidtab_search(&sidtab, sid);
1107 if (!context) {
1108 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1109 __func__, sid);
1110 rc = -EINVAL;
1111 goto out_unlock;
1112 }
1113 rc = context_struct_to_string(context, scontext, scontext_len);
1114out_unlock:
1115 read_unlock(&policy_rwlock);
1116out:
1117 return rc;
1118
1119}
1120
1121/**
1122 * security_sid_to_context - Obtain a context for a given SID.
1123 * @sid: security identifier, SID
1124 * @scontext: security context
1125 * @scontext_len: length in bytes
1126 *
1127 * Write the string representation of the context associated with @sid
1128 * into a dynamically allocated string of the correct size. Set @scontext
1129 * to point to this string and set @scontext_len to the length of the string.
1130 */
1131int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1132{
1133 return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1134}
1135
1136int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1137{
1138 return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1139}
1140
1141/*
1142 * Caveat: Mutates scontext.
1143 */
1144static int string_to_context_struct(struct policydb *pol,
1145 struct sidtab *sidtabp,
1146 char *scontext,
1147 u32 scontext_len,
1148 struct context *ctx,
1149 u32 def_sid)
1150{
1151 struct role_datum *role;
1152 struct type_datum *typdatum;
1153 struct user_datum *usrdatum;
1154 char *scontextp, *p, oldc;
1155 int rc = 0;
1156
1157 context_init(ctx);
1158
1159 /* Parse the security context. */
1160
1161 rc = -EINVAL;
1162 scontextp = (char *) scontext;
1163
1164 /* Extract the user. */
1165 p = scontextp;
1166 while (*p && *p != ':')
1167 p++;
1168
1169 if (*p == 0)
1170 goto out;
1171
1172 *p++ = 0;
1173
1174 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1175 if (!usrdatum)
1176 goto out;
1177
1178 ctx->user = usrdatum->value;
1179
1180 /* Extract role. */
1181 scontextp = p;
1182 while (*p && *p != ':')
1183 p++;
1184
1185 if (*p == 0)
1186 goto out;
1187
1188 *p++ = 0;
1189
1190 role = hashtab_search(pol->p_roles.table, scontextp);
1191 if (!role)
1192 goto out;
1193 ctx->role = role->value;
1194
1195 /* Extract type. */
1196 scontextp = p;
1197 while (*p && *p != ':')
1198 p++;
1199 oldc = *p;
1200 *p++ = 0;
1201
1202 typdatum = hashtab_search(pol->p_types.table, scontextp);
1203 if (!typdatum || typdatum->attribute)
1204 goto out;
1205
1206 ctx->type = typdatum->value;
1207
1208 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1209 if (rc)
1210 goto out;
1211
1212 rc = -EINVAL;
1213 if ((p - scontext) < scontext_len)
1214 goto out;
1215
1216 /* Check the validity of the new context. */
1217 if (!policydb_context_isvalid(pol, ctx))
1218 goto out;
1219 rc = 0;
1220out:
1221 if (rc)
1222 context_destroy(ctx);
1223 return rc;
1224}
1225
1226static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1227 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1228 int force)
1229{
1230 char *scontext2, *str = NULL;
1231 struct context context;
1232 int rc = 0;
1233
1234 if (!ss_initialized) {
1235 int i;
1236
1237 for (i = 1; i < SECINITSID_NUM; i++) {
1238 if (!strcmp(initial_sid_to_string[i], scontext)) {
1239 *sid = i;
1240 return 0;
1241 }
1242 }
1243 *sid = SECINITSID_KERNEL;
1244 return 0;
1245 }
1246 *sid = SECSID_NULL;
1247
1248 /* Copy the string so that we can modify the copy as we parse it. */
1249 scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1250 if (!scontext2)
1251 return -ENOMEM;
1252 memcpy(scontext2, scontext, scontext_len);
1253 scontext2[scontext_len] = 0;
1254
1255 if (force) {
1256 /* Save another copy for storing in uninterpreted form */
1257 rc = -ENOMEM;
1258 str = kstrdup(scontext2, gfp_flags);
1259 if (!str)
1260 goto out;
1261 }
1262
1263 read_lock(&policy_rwlock);
1264 rc = string_to_context_struct(&policydb, &sidtab, scontext2,
1265 scontext_len, &context, def_sid);
1266 if (rc == -EINVAL && force) {
1267 context.str = str;
1268 context.len = scontext_len;
1269 str = NULL;
1270 } else if (rc)
1271 goto out_unlock;
1272 rc = sidtab_context_to_sid(&sidtab, &context, sid);
1273 context_destroy(&context);
1274out_unlock:
1275 read_unlock(&policy_rwlock);
1276out:
1277 kfree(scontext2);
1278 kfree(str);
1279 return rc;
1280}
1281
1282/**
1283 * security_context_to_sid - Obtain a SID for a given security context.
1284 * @scontext: security context
1285 * @scontext_len: length in bytes
1286 * @sid: security identifier, SID
1287 *
1288 * Obtains a SID associated with the security context that
1289 * has the string representation specified by @scontext.
1290 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1291 * memory is available, or 0 on success.
1292 */
1293int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
1294{
1295 return security_context_to_sid_core(scontext, scontext_len,
1296 sid, SECSID_NULL, GFP_KERNEL, 0);
1297}
1298
1299/**
1300 * security_context_to_sid_default - Obtain a SID for a given security context,
1301 * falling back to specified default if needed.
1302 *
1303 * @scontext: security context
1304 * @scontext_len: length in bytes
1305 * @sid: security identifier, SID
1306 * @def_sid: default SID to assign on error
1307 *
1308 * Obtains a SID associated with the security context that
1309 * has the string representation specified by @scontext.
1310 * The default SID is passed to the MLS layer to be used to allow
1311 * kernel labeling of the MLS field if the MLS field is not present
1312 * (for upgrading to MLS without full relabel).
1313 * Implicitly forces adding of the context even if it cannot be mapped yet.
1314 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1315 * memory is available, or 0 on success.
1316 */
1317int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1318 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1319{
1320 return security_context_to_sid_core(scontext, scontext_len,
1321 sid, def_sid, gfp_flags, 1);
1322}
1323
1324int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1325 u32 *sid)
1326{
1327 return security_context_to_sid_core(scontext, scontext_len,
1328 sid, SECSID_NULL, GFP_KERNEL, 1);
1329}
1330
1331static int compute_sid_handle_invalid_context(
1332 struct context *scontext,
1333 struct context *tcontext,
1334 u16 tclass,
1335 struct context *newcontext)
1336{
1337 char *s = NULL, *t = NULL, *n = NULL;
1338 u32 slen, tlen, nlen;
1339
1340 if (context_struct_to_string(scontext, &s, &slen))
1341 goto out;
1342 if (context_struct_to_string(tcontext, &t, &tlen))
1343 goto out;
1344 if (context_struct_to_string(newcontext, &n, &nlen))
1345 goto out;
1346 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1347 "security_compute_sid: invalid context %s"
1348 " for scontext=%s"
1349 " tcontext=%s"
1350 " tclass=%s",
1351 n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
1352out:
1353 kfree(s);
1354 kfree(t);
1355 kfree(n);
1356 if (!selinux_enforcing)
1357 return 0;
1358 return -EACCES;
1359}
1360
1361static void filename_compute_type(struct policydb *p, struct context *newcontext,
1362 u32 stype, u32 ttype, u16 tclass,
1363 const char *objname)
1364{
1365 struct filename_trans ft;
1366 struct filename_trans_datum *otype;
1367
1368 /*
1369 * Most filename trans rules are going to live in specific directories
1370 * like /dev or /var/run. This bitmap will quickly skip rule searches
1371 * if the ttype does not contain any rules.
1372 */
1373 if (!ebitmap_get_bit(&p->filename_trans_ttypes, ttype))
1374 return;
1375
1376 ft.stype = stype;
1377 ft.ttype = ttype;
1378 ft.tclass = tclass;
1379 ft.name = objname;
1380
1381 otype = hashtab_search(p->filename_trans, &ft);
1382 if (otype)
1383 newcontext->type = otype->otype;
1384}
1385
1386static int security_compute_sid(u32 ssid,
1387 u32 tsid,
1388 u16 orig_tclass,
1389 u32 specified,
1390 const char *objname,
1391 u32 *out_sid,
1392 bool kern)
1393{
1394 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1395 struct role_trans *roletr = NULL;
1396 struct avtab_key avkey;
1397 struct avtab_datum *avdatum;
1398 struct avtab_node *node;
1399 u16 tclass;
1400 int rc = 0;
1401 bool sock;
1402
1403 if (!ss_initialized) {
1404 switch (orig_tclass) {
1405 case SECCLASS_PROCESS: /* kernel value */
1406 *out_sid = ssid;
1407 break;
1408 default:
1409 *out_sid = tsid;
1410 break;
1411 }
1412 goto out;
1413 }
1414
1415 context_init(&newcontext);
1416
1417 read_lock(&policy_rwlock);
1418
1419 if (kern) {
1420 tclass = unmap_class(orig_tclass);
1421 sock = security_is_socket_class(orig_tclass);
1422 } else {
1423 tclass = orig_tclass;
1424 sock = security_is_socket_class(map_class(tclass));
1425 }
1426
1427 scontext = sidtab_search(&sidtab, ssid);
1428 if (!scontext) {
1429 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1430 __func__, ssid);
1431 rc = -EINVAL;
1432 goto out_unlock;
1433 }
1434 tcontext = sidtab_search(&sidtab, tsid);
1435 if (!tcontext) {
1436 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1437 __func__, tsid);
1438 rc = -EINVAL;
1439 goto out_unlock;
1440 }
1441
1442 /* Set the user identity. */
1443 switch (specified) {
1444 case AVTAB_TRANSITION:
1445 case AVTAB_CHANGE:
1446 /* Use the process user identity. */
1447 newcontext.user = scontext->user;
1448 break;
1449 case AVTAB_MEMBER:
1450 /* Use the related object owner. */
1451 newcontext.user = tcontext->user;
1452 break;
1453 }
1454
1455 /* Set the role and type to default values. */
1456 if ((tclass == policydb.process_class) || (sock == true)) {
1457 /* Use the current role and type of process. */
1458 newcontext.role = scontext->role;
1459 newcontext.type = scontext->type;
1460 } else {
1461 /* Use the well-defined object role. */
1462 newcontext.role = OBJECT_R_VAL;
1463 /* Use the type of the related object. */
1464 newcontext.type = tcontext->type;
1465 }
1466
1467 /* Look for a type transition/member/change rule. */
1468 avkey.source_type = scontext->type;
1469 avkey.target_type = tcontext->type;
1470 avkey.target_class = tclass;
1471 avkey.specified = specified;
1472 avdatum = avtab_search(&policydb.te_avtab, &avkey);
1473
1474 /* If no permanent rule, also check for enabled conditional rules */
1475 if (!avdatum) {
1476 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1477 for (; node; node = avtab_search_node_next(node, specified)) {
1478 if (node->key.specified & AVTAB_ENABLED) {
1479 avdatum = &node->datum;
1480 break;
1481 }
1482 }
1483 }
1484
1485 if (avdatum) {
1486 /* Use the type from the type transition/member/change rule. */
1487 newcontext.type = avdatum->data;
1488 }
1489
1490 /* if we have a objname this is a file trans check so check those rules */
1491 if (objname)
1492 filename_compute_type(&policydb, &newcontext, scontext->type,
1493 tcontext->type, tclass, objname);
1494
1495 /* Check for class-specific changes. */
1496 if (specified & AVTAB_TRANSITION) {
1497 /* Look for a role transition rule. */
1498 for (roletr = policydb.role_tr; roletr; roletr = roletr->next) {
1499 if ((roletr->role == scontext->role) &&
1500 (roletr->type == tcontext->type) &&
1501 (roletr->tclass == tclass)) {
1502 /* Use the role transition rule. */
1503 newcontext.role = roletr->new_role;
1504 break;
1505 }
1506 }
1507 }
1508
1509 /* Set the MLS attributes.
1510 This is done last because it may allocate memory. */
1511 rc = mls_compute_sid(scontext, tcontext, tclass, specified,
1512 &newcontext, sock);
1513 if (rc)
1514 goto out_unlock;
1515
1516 /* Check the validity of the context. */
1517 if (!policydb_context_isvalid(&policydb, &newcontext)) {
1518 rc = compute_sid_handle_invalid_context(scontext,
1519 tcontext,
1520 tclass,
1521 &newcontext);
1522 if (rc)
1523 goto out_unlock;
1524 }
1525 /* Obtain the sid for the context. */
1526 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1527out_unlock:
1528 read_unlock(&policy_rwlock);
1529 context_destroy(&newcontext);
1530out:
1531 return rc;
1532}
1533
1534/**
1535 * security_transition_sid - Compute the SID for a new subject/object.
1536 * @ssid: source security identifier
1537 * @tsid: target security identifier
1538 * @tclass: target security class
1539 * @out_sid: security identifier for new subject/object
1540 *
1541 * Compute a SID to use for labeling a new subject or object in the
1542 * class @tclass based on a SID pair (@ssid, @tsid).
1543 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1544 * if insufficient memory is available, or %0 if the new SID was
1545 * computed successfully.
1546 */
1547int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1548 const struct qstr *qstr, u32 *out_sid)
1549{
1550 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1551 qstr ? qstr->name : NULL, out_sid, true);
1552}
1553
1554int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
1555 const char *objname, u32 *out_sid)
1556{
1557 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1558 objname, out_sid, false);
1559}
1560
1561/**
1562 * security_member_sid - Compute the SID for member selection.
1563 * @ssid: source security identifier
1564 * @tsid: target security identifier
1565 * @tclass: target security class
1566 * @out_sid: security identifier for selected member
1567 *
1568 * Compute a SID to use when selecting a member of a polyinstantiated
1569 * object of class @tclass based on a SID pair (@ssid, @tsid).
1570 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1571 * if insufficient memory is available, or %0 if the SID was
1572 * computed successfully.
1573 */
1574int security_member_sid(u32 ssid,
1575 u32 tsid,
1576 u16 tclass,
1577 u32 *out_sid)
1578{
1579 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL,
1580 out_sid, false);
1581}
1582
1583/**
1584 * security_change_sid - Compute the SID for object relabeling.
1585 * @ssid: source security identifier
1586 * @tsid: target security identifier
1587 * @tclass: target security class
1588 * @out_sid: security identifier for selected member
1589 *
1590 * Compute a SID to use for relabeling an object of class @tclass
1591 * based on a SID pair (@ssid, @tsid).
1592 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1593 * if insufficient memory is available, or %0 if the SID was
1594 * computed successfully.
1595 */
1596int security_change_sid(u32 ssid,
1597 u32 tsid,
1598 u16 tclass,
1599 u32 *out_sid)
1600{
1601 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1602 out_sid, false);
1603}
1604
1605/* Clone the SID into the new SID table. */
1606static int clone_sid(u32 sid,
1607 struct context *context,
1608 void *arg)
1609{
1610 struct sidtab *s = arg;
1611
1612 if (sid > SECINITSID_NUM)
1613 return sidtab_insert(s, sid, context);
1614 else
1615 return 0;
1616}
1617
1618static inline int convert_context_handle_invalid_context(struct context *context)
1619{
1620 char *s;
1621 u32 len;
1622
1623 if (selinux_enforcing)
1624 return -EINVAL;
1625
1626 if (!context_struct_to_string(context, &s, &len)) {
1627 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s);
1628 kfree(s);
1629 }
1630 return 0;
1631}
1632
1633struct convert_context_args {
1634 struct policydb *oldp;
1635 struct policydb *newp;
1636};
1637
1638/*
1639 * Convert the values in the security context
1640 * structure `c' from the values specified
1641 * in the policy `p->oldp' to the values specified
1642 * in the policy `p->newp'. Verify that the
1643 * context is valid under the new policy.
1644 */
1645static int convert_context(u32 key,
1646 struct context *c,
1647 void *p)
1648{
1649 struct convert_context_args *args;
1650 struct context oldc;
1651 struct ocontext *oc;
1652 struct mls_range *range;
1653 struct role_datum *role;
1654 struct type_datum *typdatum;
1655 struct user_datum *usrdatum;
1656 char *s;
1657 u32 len;
1658 int rc = 0;
1659
1660 if (key <= SECINITSID_NUM)
1661 goto out;
1662
1663 args = p;
1664
1665 if (c->str) {
1666 struct context ctx;
1667
1668 rc = -ENOMEM;
1669 s = kstrdup(c->str, GFP_KERNEL);
1670 if (!s)
1671 goto out;
1672
1673 rc = string_to_context_struct(args->newp, NULL, s,
1674 c->len, &ctx, SECSID_NULL);
1675 kfree(s);
1676 if (!rc) {
1677 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n",
1678 c->str);
1679 /* Replace string with mapped representation. */
1680 kfree(c->str);
1681 memcpy(c, &ctx, sizeof(*c));
1682 goto out;
1683 } else if (rc == -EINVAL) {
1684 /* Retain string representation for later mapping. */
1685 rc = 0;
1686 goto out;
1687 } else {
1688 /* Other error condition, e.g. ENOMEM. */
1689 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n",
1690 c->str, -rc);
1691 goto out;
1692 }
1693 }
1694
1695 rc = context_cpy(&oldc, c);
1696 if (rc)
1697 goto out;
1698
1699 /* Convert the user. */
1700 rc = -EINVAL;
1701 usrdatum = hashtab_search(args->newp->p_users.table,
1702 sym_name(args->oldp, SYM_USERS, c->user - 1));
1703 if (!usrdatum)
1704 goto bad;
1705 c->user = usrdatum->value;
1706
1707 /* Convert the role. */
1708 rc = -EINVAL;
1709 role = hashtab_search(args->newp->p_roles.table,
1710 sym_name(args->oldp, SYM_ROLES, c->role - 1));
1711 if (!role)
1712 goto bad;
1713 c->role = role->value;
1714
1715 /* Convert the type. */
1716 rc = -EINVAL;
1717 typdatum = hashtab_search(args->newp->p_types.table,
1718 sym_name(args->oldp, SYM_TYPES, c->type - 1));
1719 if (!typdatum)
1720 goto bad;
1721 c->type = typdatum->value;
1722
1723 /* Convert the MLS fields if dealing with MLS policies */
1724 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1725 rc = mls_convert_context(args->oldp, args->newp, c);
1726 if (rc)
1727 goto bad;
1728 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1729 /*
1730 * Switching between MLS and non-MLS policy:
1731 * free any storage used by the MLS fields in the
1732 * context for all existing entries in the sidtab.
1733 */
1734 mls_context_destroy(c);
1735 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1736 /*
1737 * Switching between non-MLS and MLS policy:
1738 * ensure that the MLS fields of the context for all
1739 * existing entries in the sidtab are filled in with a
1740 * suitable default value, likely taken from one of the
1741 * initial SIDs.
1742 */
1743 oc = args->newp->ocontexts[OCON_ISID];
1744 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1745 oc = oc->next;
1746 rc = -EINVAL;
1747 if (!oc) {
1748 printk(KERN_ERR "SELinux: unable to look up"
1749 " the initial SIDs list\n");
1750 goto bad;
1751 }
1752 range = &oc->context[0].range;
1753 rc = mls_range_set(c, range);
1754 if (rc)
1755 goto bad;
1756 }
1757
1758 /* Check the validity of the new context. */
1759 if (!policydb_context_isvalid(args->newp, c)) {
1760 rc = convert_context_handle_invalid_context(&oldc);
1761 if (rc)
1762 goto bad;
1763 }
1764
1765 context_destroy(&oldc);
1766
1767 rc = 0;
1768out:
1769 return rc;
1770bad:
1771 /* Map old representation to string and save it. */
1772 rc = context_struct_to_string(&oldc, &s, &len);
1773 if (rc)
1774 return rc;
1775 context_destroy(&oldc);
1776 context_destroy(c);
1777 c->str = s;
1778 c->len = len;
1779 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n",
1780 c->str);
1781 rc = 0;
1782 goto out;
1783}
1784
1785static void security_load_policycaps(void)
1786{
1787 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1788 POLICYDB_CAPABILITY_NETPEER);
1789 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1790 POLICYDB_CAPABILITY_OPENPERM);
1791}
1792
1793extern void selinux_complete_init(void);
1794static int security_preserve_bools(struct policydb *p);
1795
1796/**
1797 * security_load_policy - Load a security policy configuration.
1798 * @data: binary policy data
1799 * @len: length of data in bytes
1800 *
1801 * Load a new set of security policy configuration data,
1802 * validate it and convert the SID table as necessary.
1803 * This function will flush the access vector cache after
1804 * loading the new policy.
1805 */
1806int security_load_policy(void *data, size_t len)
1807{
1808 struct policydb oldpolicydb, newpolicydb;
1809 struct sidtab oldsidtab, newsidtab;
1810 struct selinux_mapping *oldmap, *map = NULL;
1811 struct convert_context_args args;
1812 u32 seqno;
1813 u16 map_size;
1814 int rc = 0;
1815 struct policy_file file = { data, len }, *fp = &file;
1816
1817 if (!ss_initialized) {
1818 avtab_cache_init();
1819 rc = policydb_read(&policydb, fp);
1820 if (rc) {
1821 avtab_cache_destroy();
1822 return rc;
1823 }
1824
1825 policydb.len = len;
1826 rc = selinux_set_mapping(&policydb, secclass_map,
1827 ¤t_mapping,
1828 ¤t_mapping_size);
1829 if (rc) {
1830 policydb_destroy(&policydb);
1831 avtab_cache_destroy();
1832 return rc;
1833 }
1834
1835 rc = policydb_load_isids(&policydb, &sidtab);
1836 if (rc) {
1837 policydb_destroy(&policydb);
1838 avtab_cache_destroy();
1839 return rc;
1840 }
1841
1842 security_load_policycaps();
1843 ss_initialized = 1;
1844 seqno = ++latest_granting;
1845 selinux_complete_init();
1846 avc_ss_reset(seqno);
1847 selnl_notify_policyload(seqno);
1848 selinux_status_update_policyload(seqno);
1849 selinux_netlbl_cache_invalidate();
1850 selinux_xfrm_notify_policyload();
1851 return 0;
1852 }
1853
1854#if 0
1855 sidtab_hash_eval(&sidtab, "sids");
1856#endif
1857
1858 rc = policydb_read(&newpolicydb, fp);
1859 if (rc)
1860 return rc;
1861
1862 newpolicydb.len = len;
1863 /* If switching between different policy types, log MLS status */
1864 if (policydb.mls_enabled && !newpolicydb.mls_enabled)
1865 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
1866 else if (!policydb.mls_enabled && newpolicydb.mls_enabled)
1867 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
1868
1869 rc = policydb_load_isids(&newpolicydb, &newsidtab);
1870 if (rc) {
1871 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
1872 policydb_destroy(&newpolicydb);
1873 return rc;
1874 }
1875
1876 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size);
1877 if (rc)
1878 goto err;
1879
1880 rc = security_preserve_bools(&newpolicydb);
1881 if (rc) {
1882 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
1883 goto err;
1884 }
1885
1886 /* Clone the SID table. */
1887 sidtab_shutdown(&sidtab);
1888
1889 rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
1890 if (rc)
1891 goto err;
1892
1893 /*
1894 * Convert the internal representations of contexts
1895 * in the new SID table.
1896 */
1897 args.oldp = &policydb;
1898 args.newp = &newpolicydb;
1899 rc = sidtab_map(&newsidtab, convert_context, &args);
1900 if (rc) {
1901 printk(KERN_ERR "SELinux: unable to convert the internal"
1902 " representation of contexts in the new SID"
1903 " table\n");
1904 goto err;
1905 }
1906
1907 /* Save the old policydb and SID table to free later. */
1908 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1909 sidtab_set(&oldsidtab, &sidtab);
1910
1911 /* Install the new policydb and SID table. */
1912 write_lock_irq(&policy_rwlock);
1913 memcpy(&policydb, &newpolicydb, sizeof policydb);
1914 sidtab_set(&sidtab, &newsidtab);
1915 security_load_policycaps();
1916 oldmap = current_mapping;
1917 current_mapping = map;
1918 current_mapping_size = map_size;
1919 seqno = ++latest_granting;
1920 write_unlock_irq(&policy_rwlock);
1921
1922 /* Free the old policydb and SID table. */
1923 policydb_destroy(&oldpolicydb);
1924 sidtab_destroy(&oldsidtab);
1925 kfree(oldmap);
1926
1927 avc_ss_reset(seqno);
1928 selnl_notify_policyload(seqno);
1929 selinux_status_update_policyload(seqno);
1930 selinux_netlbl_cache_invalidate();
1931 selinux_xfrm_notify_policyload();
1932
1933 return 0;
1934
1935err:
1936 kfree(map);
1937 sidtab_destroy(&newsidtab);
1938 policydb_destroy(&newpolicydb);
1939 return rc;
1940
1941}
1942
1943size_t security_policydb_len(void)
1944{
1945 size_t len;
1946
1947 read_lock(&policy_rwlock);
1948 len = policydb.len;
1949 read_unlock(&policy_rwlock);
1950
1951 return len;
1952}
1953
1954/**
1955 * security_port_sid - Obtain the SID for a port.
1956 * @protocol: protocol number
1957 * @port: port number
1958 * @out_sid: security identifier
1959 */
1960int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1961{
1962 struct ocontext *c;
1963 int rc = 0;
1964
1965 read_lock(&policy_rwlock);
1966
1967 c = policydb.ocontexts[OCON_PORT];
1968 while (c) {
1969 if (c->u.port.protocol == protocol &&
1970 c->u.port.low_port <= port &&
1971 c->u.port.high_port >= port)
1972 break;
1973 c = c->next;
1974 }
1975
1976 if (c) {
1977 if (!c->sid[0]) {
1978 rc = sidtab_context_to_sid(&sidtab,
1979 &c->context[0],
1980 &c->sid[0]);
1981 if (rc)
1982 goto out;
1983 }
1984 *out_sid = c->sid[0];
1985 } else {
1986 *out_sid = SECINITSID_PORT;
1987 }
1988
1989out:
1990 read_unlock(&policy_rwlock);
1991 return rc;
1992}
1993
1994/**
1995 * security_netif_sid - Obtain the SID for a network interface.
1996 * @name: interface name
1997 * @if_sid: interface SID
1998 */
1999int security_netif_sid(char *name, u32 *if_sid)
2000{
2001 int rc = 0;
2002 struct ocontext *c;
2003
2004 read_lock(&policy_rwlock);
2005
2006 c = policydb.ocontexts[OCON_NETIF];
2007 while (c) {
2008 if (strcmp(name, c->u.name) == 0)
2009 break;
2010 c = c->next;
2011 }
2012
2013 if (c) {
2014 if (!c->sid[0] || !c->sid[1]) {
2015 rc = sidtab_context_to_sid(&sidtab,
2016 &c->context[0],
2017 &c->sid[0]);
2018 if (rc)
2019 goto out;
2020 rc = sidtab_context_to_sid(&sidtab,
2021 &c->context[1],
2022 &c->sid[1]);
2023 if (rc)
2024 goto out;
2025 }
2026 *if_sid = c->sid[0];
2027 } else
2028 *if_sid = SECINITSID_NETIF;
2029
2030out:
2031 read_unlock(&policy_rwlock);
2032 return rc;
2033}
2034
2035static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2036{
2037 int i, fail = 0;
2038
2039 for (i = 0; i < 4; i++)
2040 if (addr[i] != (input[i] & mask[i])) {
2041 fail = 1;
2042 break;
2043 }
2044
2045 return !fail;
2046}
2047
2048/**
2049 * security_node_sid - Obtain the SID for a node (host).
2050 * @domain: communication domain aka address family
2051 * @addrp: address
2052 * @addrlen: address length in bytes
2053 * @out_sid: security identifier
2054 */
2055int security_node_sid(u16 domain,
2056 void *addrp,
2057 u32 addrlen,
2058 u32 *out_sid)
2059{
2060 int rc;
2061 struct ocontext *c;
2062
2063 read_lock(&policy_rwlock);
2064
2065 switch (domain) {
2066 case AF_INET: {
2067 u32 addr;
2068
2069 rc = -EINVAL;
2070 if (addrlen != sizeof(u32))
2071 goto out;
2072
2073 addr = *((u32 *)addrp);
2074
2075 c = policydb.ocontexts[OCON_NODE];
2076 while (c) {
2077 if (c->u.node.addr == (addr & c->u.node.mask))
2078 break;
2079 c = c->next;
2080 }
2081 break;
2082 }
2083
2084 case AF_INET6:
2085 rc = -EINVAL;
2086 if (addrlen != sizeof(u64) * 2)
2087 goto out;
2088 c = policydb.ocontexts[OCON_NODE6];
2089 while (c) {
2090 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2091 c->u.node6.mask))
2092 break;
2093 c = c->next;
2094 }
2095 break;
2096
2097 default:
2098 rc = 0;
2099 *out_sid = SECINITSID_NODE;
2100 goto out;
2101 }
2102
2103 if (c) {
2104 if (!c->sid[0]) {
2105 rc = sidtab_context_to_sid(&sidtab,
2106 &c->context[0],
2107 &c->sid[0]);
2108 if (rc)
2109 goto out;
2110 }
2111 *out_sid = c->sid[0];
2112 } else {
2113 *out_sid = SECINITSID_NODE;
2114 }
2115
2116 rc = 0;
2117out:
2118 read_unlock(&policy_rwlock);
2119 return rc;
2120}
2121
2122#define SIDS_NEL 25
2123
2124/**
2125 * security_get_user_sids - Obtain reachable SIDs for a user.
2126 * @fromsid: starting SID
2127 * @username: username
2128 * @sids: array of reachable SIDs for user
2129 * @nel: number of elements in @sids
2130 *
2131 * Generate the set of SIDs for legal security contexts
2132 * for a given user that can be reached by @fromsid.
2133 * Set *@sids to point to a dynamically allocated
2134 * array containing the set of SIDs. Set *@nel to the
2135 * number of elements in the array.
2136 */
2137
2138int security_get_user_sids(u32 fromsid,
2139 char *username,
2140 u32 **sids,
2141 u32 *nel)
2142{
2143 struct context *fromcon, usercon;
2144 u32 *mysids = NULL, *mysids2, sid;
2145 u32 mynel = 0, maxnel = SIDS_NEL;
2146 struct user_datum *user;
2147 struct role_datum *role;
2148 struct ebitmap_node *rnode, *tnode;
2149 int rc = 0, i, j;
2150
2151 *sids = NULL;
2152 *nel = 0;
2153
2154 if (!ss_initialized)
2155 goto out;
2156
2157 read_lock(&policy_rwlock);
2158
2159 context_init(&usercon);
2160
2161 rc = -EINVAL;
2162 fromcon = sidtab_search(&sidtab, fromsid);
2163 if (!fromcon)
2164 goto out_unlock;
2165
2166 rc = -EINVAL;
2167 user = hashtab_search(policydb.p_users.table, username);
2168 if (!user)
2169 goto out_unlock;
2170
2171 usercon.user = user->value;
2172
2173 rc = -ENOMEM;
2174 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2175 if (!mysids)
2176 goto out_unlock;
2177
2178 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2179 role = policydb.role_val_to_struct[i];
2180 usercon.role = i + 1;
2181 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2182 usercon.type = j + 1;
2183
2184 if (mls_setup_user_range(fromcon, user, &usercon))
2185 continue;
2186
2187 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2188 if (rc)
2189 goto out_unlock;
2190 if (mynel < maxnel) {
2191 mysids[mynel++] = sid;
2192 } else {
2193 rc = -ENOMEM;
2194 maxnel += SIDS_NEL;
2195 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2196 if (!mysids2)
2197 goto out_unlock;
2198 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2199 kfree(mysids);
2200 mysids = mysids2;
2201 mysids[mynel++] = sid;
2202 }
2203 }
2204 }
2205 rc = 0;
2206out_unlock:
2207 read_unlock(&policy_rwlock);
2208 if (rc || !mynel) {
2209 kfree(mysids);
2210 goto out;
2211 }
2212
2213 rc = -ENOMEM;
2214 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2215 if (!mysids2) {
2216 kfree(mysids);
2217 goto out;
2218 }
2219 for (i = 0, j = 0; i < mynel; i++) {
2220 struct av_decision dummy_avd;
2221 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2222 SECCLASS_PROCESS, /* kernel value */
2223 PROCESS__TRANSITION, AVC_STRICT,
2224 &dummy_avd);
2225 if (!rc)
2226 mysids2[j++] = mysids[i];
2227 cond_resched();
2228 }
2229 rc = 0;
2230 kfree(mysids);
2231 *sids = mysids2;
2232 *nel = j;
2233out:
2234 return rc;
2235}
2236
2237/**
2238 * security_genfs_sid - Obtain a SID for a file in a filesystem
2239 * @fstype: filesystem type
2240 * @path: path from root of mount
2241 * @sclass: file security class
2242 * @sid: SID for path
2243 *
2244 * Obtain a SID to use for a file in a filesystem that
2245 * cannot support xattr or use a fixed labeling behavior like
2246 * transition SIDs or task SIDs.
2247 */
2248int security_genfs_sid(const char *fstype,
2249 char *path,
2250 u16 orig_sclass,
2251 u32 *sid)
2252{
2253 int len;
2254 u16 sclass;
2255 struct genfs *genfs;
2256 struct ocontext *c;
2257 int rc, cmp = 0;
2258
2259 while (path[0] == '/' && path[1] == '/')
2260 path++;
2261
2262 read_lock(&policy_rwlock);
2263
2264 sclass = unmap_class(orig_sclass);
2265 *sid = SECINITSID_UNLABELED;
2266
2267 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2268 cmp = strcmp(fstype, genfs->fstype);
2269 if (cmp <= 0)
2270 break;
2271 }
2272
2273 rc = -ENOENT;
2274 if (!genfs || cmp)
2275 goto out;
2276
2277 for (c = genfs->head; c; c = c->next) {
2278 len = strlen(c->u.name);
2279 if ((!c->v.sclass || sclass == c->v.sclass) &&
2280 (strncmp(c->u.name, path, len) == 0))
2281 break;
2282 }
2283
2284 rc = -ENOENT;
2285 if (!c)
2286 goto out;
2287
2288 if (!c->sid[0]) {
2289 rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]);
2290 if (rc)
2291 goto out;
2292 }
2293
2294 *sid = c->sid[0];
2295 rc = 0;
2296out:
2297 read_unlock(&policy_rwlock);
2298 return rc;
2299}
2300
2301/**
2302 * security_fs_use - Determine how to handle labeling for a filesystem.
2303 * @fstype: filesystem type
2304 * @behavior: labeling behavior
2305 * @sid: SID for filesystem (superblock)
2306 */
2307int security_fs_use(
2308 const char *fstype,
2309 unsigned int *behavior,
2310 u32 *sid)
2311{
2312 int rc = 0;
2313 struct ocontext *c;
2314
2315 read_lock(&policy_rwlock);
2316
2317 c = policydb.ocontexts[OCON_FSUSE];
2318 while (c) {
2319 if (strcmp(fstype, c->u.name) == 0)
2320 break;
2321 c = c->next;
2322 }
2323
2324 if (c) {
2325 *behavior = c->v.behavior;
2326 if (!c->sid[0]) {
2327 rc = sidtab_context_to_sid(&sidtab, &c->context[0],
2328 &c->sid[0]);
2329 if (rc)
2330 goto out;
2331 }
2332 *sid = c->sid[0];
2333 } else {
2334 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
2335 if (rc) {
2336 *behavior = SECURITY_FS_USE_NONE;
2337 rc = 0;
2338 } else {
2339 *behavior = SECURITY_FS_USE_GENFS;
2340 }
2341 }
2342
2343out:
2344 read_unlock(&policy_rwlock);
2345 return rc;
2346}
2347
2348int security_get_bools(int *len, char ***names, int **values)
2349{
2350 int i, rc;
2351
2352 read_lock(&policy_rwlock);
2353 *names = NULL;
2354 *values = NULL;
2355
2356 rc = 0;
2357 *len = policydb.p_bools.nprim;
2358 if (!*len)
2359 goto out;
2360
2361 rc = -ENOMEM;
2362 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2363 if (!*names)
2364 goto err;
2365
2366 rc = -ENOMEM;
2367 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2368 if (!*values)
2369 goto err;
2370
2371 for (i = 0; i < *len; i++) {
2372 size_t name_len;
2373
2374 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2375 name_len = strlen(sym_name(&policydb, SYM_BOOLS, i)) + 1;
2376
2377 rc = -ENOMEM;
2378 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
2379 if (!(*names)[i])
2380 goto err;
2381
2382 strncpy((*names)[i], sym_name(&policydb, SYM_BOOLS, i), name_len);
2383 (*names)[i][name_len - 1] = 0;
2384 }
2385 rc = 0;
2386out:
2387 read_unlock(&policy_rwlock);
2388 return rc;
2389err:
2390 if (*names) {
2391 for (i = 0; i < *len; i++)
2392 kfree((*names)[i]);
2393 }
2394 kfree(*values);
2395 goto out;
2396}
2397
2398
2399int security_set_bools(int len, int *values)
2400{
2401 int i, rc;
2402 int lenp, seqno = 0;
2403 struct cond_node *cur;
2404
2405 write_lock_irq(&policy_rwlock);
2406
2407 rc = -EFAULT;
2408 lenp = policydb.p_bools.nprim;
2409 if (len != lenp)
2410 goto out;
2411
2412 for (i = 0; i < len; i++) {
2413 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2414 audit_log(current->audit_context, GFP_ATOMIC,
2415 AUDIT_MAC_CONFIG_CHANGE,
2416 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2417 sym_name(&policydb, SYM_BOOLS, i),
2418 !!values[i],
2419 policydb.bool_val_to_struct[i]->state,
2420 audit_get_loginuid(current),
2421 audit_get_sessionid(current));
2422 }
2423 if (values[i])
2424 policydb.bool_val_to_struct[i]->state = 1;
2425 else
2426 policydb.bool_val_to_struct[i]->state = 0;
2427 }
2428
2429 for (cur = policydb.cond_list; cur; cur = cur->next) {
2430 rc = evaluate_cond_node(&policydb, cur);
2431 if (rc)
2432 goto out;
2433 }
2434
2435 seqno = ++latest_granting;
2436 rc = 0;
2437out:
2438 write_unlock_irq(&policy_rwlock);
2439 if (!rc) {
2440 avc_ss_reset(seqno);
2441 selnl_notify_policyload(seqno);
2442 selinux_status_update_policyload(seqno);
2443 selinux_xfrm_notify_policyload();
2444 }
2445 return rc;
2446}
2447
2448int security_get_bool_value(int bool)
2449{
2450 int rc;
2451 int len;
2452
2453 read_lock(&policy_rwlock);
2454
2455 rc = -EFAULT;
2456 len = policydb.p_bools.nprim;
2457 if (bool >= len)
2458 goto out;
2459
2460 rc = policydb.bool_val_to_struct[bool]->state;
2461out:
2462 read_unlock(&policy_rwlock);
2463 return rc;
2464}
2465
2466static int security_preserve_bools(struct policydb *p)
2467{
2468 int rc, nbools = 0, *bvalues = NULL, i;
2469 char **bnames = NULL;
2470 struct cond_bool_datum *booldatum;
2471 struct cond_node *cur;
2472
2473 rc = security_get_bools(&nbools, &bnames, &bvalues);
2474 if (rc)
2475 goto out;
2476 for (i = 0; i < nbools; i++) {
2477 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2478 if (booldatum)
2479 booldatum->state = bvalues[i];
2480 }
2481 for (cur = p->cond_list; cur; cur = cur->next) {
2482 rc = evaluate_cond_node(p, cur);
2483 if (rc)
2484 goto out;
2485 }
2486
2487out:
2488 if (bnames) {
2489 for (i = 0; i < nbools; i++)
2490 kfree(bnames[i]);
2491 }
2492 kfree(bnames);
2493 kfree(bvalues);
2494 return rc;
2495}
2496
2497/*
2498 * security_sid_mls_copy() - computes a new sid based on the given
2499 * sid and the mls portion of mls_sid.
2500 */
2501int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2502{
2503 struct context *context1;
2504 struct context *context2;
2505 struct context newcon;
2506 char *s;
2507 u32 len;
2508 int rc;
2509
2510 rc = 0;
2511 if (!ss_initialized || !policydb.mls_enabled) {
2512 *new_sid = sid;
2513 goto out;
2514 }
2515
2516 context_init(&newcon);
2517
2518 read_lock(&policy_rwlock);
2519
2520 rc = -EINVAL;
2521 context1 = sidtab_search(&sidtab, sid);
2522 if (!context1) {
2523 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2524 __func__, sid);
2525 goto out_unlock;
2526 }
2527
2528 rc = -EINVAL;
2529 context2 = sidtab_search(&sidtab, mls_sid);
2530 if (!context2) {
2531 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2532 __func__, mls_sid);
2533 goto out_unlock;
2534 }
2535
2536 newcon.user = context1->user;
2537 newcon.role = context1->role;
2538 newcon.type = context1->type;
2539 rc = mls_context_cpy(&newcon, context2);
2540 if (rc)
2541 goto out_unlock;
2542
2543 /* Check the validity of the new context. */
2544 if (!policydb_context_isvalid(&policydb, &newcon)) {
2545 rc = convert_context_handle_invalid_context(&newcon);
2546 if (rc) {
2547 if (!context_struct_to_string(&newcon, &s, &len)) {
2548 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2549 "security_sid_mls_copy: invalid context %s", s);
2550 kfree(s);
2551 }
2552 goto out_unlock;
2553 }
2554 }
2555
2556 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2557out_unlock:
2558 read_unlock(&policy_rwlock);
2559 context_destroy(&newcon);
2560out:
2561 return rc;
2562}
2563
2564/**
2565 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2566 * @nlbl_sid: NetLabel SID
2567 * @nlbl_type: NetLabel labeling protocol type
2568 * @xfrm_sid: XFRM SID
2569 *
2570 * Description:
2571 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2572 * resolved into a single SID it is returned via @peer_sid and the function
2573 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
2574 * returns a negative value. A table summarizing the behavior is below:
2575 *
2576 * | function return | @sid
2577 * ------------------------------+-----------------+-----------------
2578 * no peer labels | 0 | SECSID_NULL
2579 * single peer label | 0 | <peer_label>
2580 * multiple, consistent labels | 0 | <peer_label>
2581 * multiple, inconsistent labels | -<errno> | SECSID_NULL
2582 *
2583 */
2584int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2585 u32 xfrm_sid,
2586 u32 *peer_sid)
2587{
2588 int rc;
2589 struct context *nlbl_ctx;
2590 struct context *xfrm_ctx;
2591
2592 *peer_sid = SECSID_NULL;
2593
2594 /* handle the common (which also happens to be the set of easy) cases
2595 * right away, these two if statements catch everything involving a
2596 * single or absent peer SID/label */
2597 if (xfrm_sid == SECSID_NULL) {
2598 *peer_sid = nlbl_sid;
2599 return 0;
2600 }
2601 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2602 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2603 * is present */
2604 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2605 *peer_sid = xfrm_sid;
2606 return 0;
2607 }
2608
2609 /* we don't need to check ss_initialized here since the only way both
2610 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2611 * security server was initialized and ss_initialized was true */
2612 if (!policydb.mls_enabled)
2613 return 0;
2614
2615 read_lock(&policy_rwlock);
2616
2617 rc = -EINVAL;
2618 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2619 if (!nlbl_ctx) {
2620 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2621 __func__, nlbl_sid);
2622 goto out;
2623 }
2624 rc = -EINVAL;
2625 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2626 if (!xfrm_ctx) {
2627 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2628 __func__, xfrm_sid);
2629 goto out;
2630 }
2631 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2632 if (rc)
2633 goto out;
2634
2635 /* at present NetLabel SIDs/labels really only carry MLS
2636 * information so if the MLS portion of the NetLabel SID
2637 * matches the MLS portion of the labeled XFRM SID/label
2638 * then pass along the XFRM SID as it is the most
2639 * expressive */
2640 *peer_sid = xfrm_sid;
2641out:
2642 read_unlock(&policy_rwlock);
2643 return rc;
2644}
2645
2646static int get_classes_callback(void *k, void *d, void *args)
2647{
2648 struct class_datum *datum = d;
2649 char *name = k, **classes = args;
2650 int value = datum->value - 1;
2651
2652 classes[value] = kstrdup(name, GFP_ATOMIC);
2653 if (!classes[value])
2654 return -ENOMEM;
2655
2656 return 0;
2657}
2658
2659int security_get_classes(char ***classes, int *nclasses)
2660{
2661 int rc;
2662
2663 read_lock(&policy_rwlock);
2664
2665 rc = -ENOMEM;
2666 *nclasses = policydb.p_classes.nprim;
2667 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
2668 if (!*classes)
2669 goto out;
2670
2671 rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2672 *classes);
2673 if (rc) {
2674 int i;
2675 for (i = 0; i < *nclasses; i++)
2676 kfree((*classes)[i]);
2677 kfree(*classes);
2678 }
2679
2680out:
2681 read_unlock(&policy_rwlock);
2682 return rc;
2683}
2684
2685static int get_permissions_callback(void *k, void *d, void *args)
2686{
2687 struct perm_datum *datum = d;
2688 char *name = k, **perms = args;
2689 int value = datum->value - 1;
2690
2691 perms[value] = kstrdup(name, GFP_ATOMIC);
2692 if (!perms[value])
2693 return -ENOMEM;
2694
2695 return 0;
2696}
2697
2698int security_get_permissions(char *class, char ***perms, int *nperms)
2699{
2700 int rc, i;
2701 struct class_datum *match;
2702
2703 read_lock(&policy_rwlock);
2704
2705 rc = -EINVAL;
2706 match = hashtab_search(policydb.p_classes.table, class);
2707 if (!match) {
2708 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
2709 __func__, class);
2710 goto out;
2711 }
2712
2713 rc = -ENOMEM;
2714 *nperms = match->permissions.nprim;
2715 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
2716 if (!*perms)
2717 goto out;
2718
2719 if (match->comdatum) {
2720 rc = hashtab_map(match->comdatum->permissions.table,
2721 get_permissions_callback, *perms);
2722 if (rc)
2723 goto err;
2724 }
2725
2726 rc = hashtab_map(match->permissions.table, get_permissions_callback,
2727 *perms);
2728 if (rc)
2729 goto err;
2730
2731out:
2732 read_unlock(&policy_rwlock);
2733 return rc;
2734
2735err:
2736 read_unlock(&policy_rwlock);
2737 for (i = 0; i < *nperms; i++)
2738 kfree((*perms)[i]);
2739 kfree(*perms);
2740 return rc;
2741}
2742
2743int security_get_reject_unknown(void)
2744{
2745 return policydb.reject_unknown;
2746}
2747
2748int security_get_allow_unknown(void)
2749{
2750 return policydb.allow_unknown;
2751}
2752
2753/**
2754 * security_policycap_supported - Check for a specific policy capability
2755 * @req_cap: capability
2756 *
2757 * Description:
2758 * This function queries the currently loaded policy to see if it supports the
2759 * capability specified by @req_cap. Returns true (1) if the capability is
2760 * supported, false (0) if it isn't supported.
2761 *
2762 */
2763int security_policycap_supported(unsigned int req_cap)
2764{
2765 int rc;
2766
2767 read_lock(&policy_rwlock);
2768 rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2769 read_unlock(&policy_rwlock);
2770
2771 return rc;
2772}
2773
2774struct selinux_audit_rule {
2775 u32 au_seqno;
2776 struct context au_ctxt;
2777};
2778
2779void selinux_audit_rule_free(void *vrule)
2780{
2781 struct selinux_audit_rule *rule = vrule;
2782
2783 if (rule) {
2784 context_destroy(&rule->au_ctxt);
2785 kfree(rule);
2786 }
2787}
2788
2789int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2790{
2791 struct selinux_audit_rule *tmprule;
2792 struct role_datum *roledatum;
2793 struct type_datum *typedatum;
2794 struct user_datum *userdatum;
2795 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2796 int rc = 0;
2797
2798 *rule = NULL;
2799
2800 if (!ss_initialized)
2801 return -EOPNOTSUPP;
2802
2803 switch (field) {
2804 case AUDIT_SUBJ_USER:
2805 case AUDIT_SUBJ_ROLE:
2806 case AUDIT_SUBJ_TYPE:
2807 case AUDIT_OBJ_USER:
2808 case AUDIT_OBJ_ROLE:
2809 case AUDIT_OBJ_TYPE:
2810 /* only 'equals' and 'not equals' fit user, role, and type */
2811 if (op != Audit_equal && op != Audit_not_equal)
2812 return -EINVAL;
2813 break;
2814 case AUDIT_SUBJ_SEN:
2815 case AUDIT_SUBJ_CLR:
2816 case AUDIT_OBJ_LEV_LOW:
2817 case AUDIT_OBJ_LEV_HIGH:
2818 /* we do not allow a range, indicated by the presence of '-' */
2819 if (strchr(rulestr, '-'))
2820 return -EINVAL;
2821 break;
2822 default:
2823 /* only the above fields are valid */
2824 return -EINVAL;
2825 }
2826
2827 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2828 if (!tmprule)
2829 return -ENOMEM;
2830
2831 context_init(&tmprule->au_ctxt);
2832
2833 read_lock(&policy_rwlock);
2834
2835 tmprule->au_seqno = latest_granting;
2836
2837 switch (field) {
2838 case AUDIT_SUBJ_USER:
2839 case AUDIT_OBJ_USER:
2840 rc = -EINVAL;
2841 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2842 if (!userdatum)
2843 goto out;
2844 tmprule->au_ctxt.user = userdatum->value;
2845 break;
2846 case AUDIT_SUBJ_ROLE:
2847 case AUDIT_OBJ_ROLE:
2848 rc = -EINVAL;
2849 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2850 if (!roledatum)
2851 goto out;
2852 tmprule->au_ctxt.role = roledatum->value;
2853 break;
2854 case AUDIT_SUBJ_TYPE:
2855 case AUDIT_OBJ_TYPE:
2856 rc = -EINVAL;
2857 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2858 if (!typedatum)
2859 goto out;
2860 tmprule->au_ctxt.type = typedatum->value;
2861 break;
2862 case AUDIT_SUBJ_SEN:
2863 case AUDIT_SUBJ_CLR:
2864 case AUDIT_OBJ_LEV_LOW:
2865 case AUDIT_OBJ_LEV_HIGH:
2866 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2867 if (rc)
2868 goto out;
2869 break;
2870 }
2871 rc = 0;
2872out:
2873 read_unlock(&policy_rwlock);
2874
2875 if (rc) {
2876 selinux_audit_rule_free(tmprule);
2877 tmprule = NULL;
2878 }
2879
2880 *rule = tmprule;
2881
2882 return rc;
2883}
2884
2885/* Check to see if the rule contains any selinux fields */
2886int selinux_audit_rule_known(struct audit_krule *rule)
2887{
2888 int i;
2889
2890 for (i = 0; i < rule->field_count; i++) {
2891 struct audit_field *f = &rule->fields[i];
2892 switch (f->type) {
2893 case AUDIT_SUBJ_USER:
2894 case AUDIT_SUBJ_ROLE:
2895 case AUDIT_SUBJ_TYPE:
2896 case AUDIT_SUBJ_SEN:
2897 case AUDIT_SUBJ_CLR:
2898 case AUDIT_OBJ_USER:
2899 case AUDIT_OBJ_ROLE:
2900 case AUDIT_OBJ_TYPE:
2901 case AUDIT_OBJ_LEV_LOW:
2902 case AUDIT_OBJ_LEV_HIGH:
2903 return 1;
2904 }
2905 }
2906
2907 return 0;
2908}
2909
2910int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2911 struct audit_context *actx)
2912{
2913 struct context *ctxt;
2914 struct mls_level *level;
2915 struct selinux_audit_rule *rule = vrule;
2916 int match = 0;
2917
2918 if (!rule) {
2919 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2920 "selinux_audit_rule_match: missing rule\n");
2921 return -ENOENT;
2922 }
2923
2924 read_lock(&policy_rwlock);
2925
2926 if (rule->au_seqno < latest_granting) {
2927 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2928 "selinux_audit_rule_match: stale rule\n");
2929 match = -ESTALE;
2930 goto out;
2931 }
2932
2933 ctxt = sidtab_search(&sidtab, sid);
2934 if (!ctxt) {
2935 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2936 "selinux_audit_rule_match: unrecognized SID %d\n",
2937 sid);
2938 match = -ENOENT;
2939 goto out;
2940 }
2941
2942 /* a field/op pair that is not caught here will simply fall through
2943 without a match */
2944 switch (field) {
2945 case AUDIT_SUBJ_USER:
2946 case AUDIT_OBJ_USER:
2947 switch (op) {
2948 case Audit_equal:
2949 match = (ctxt->user == rule->au_ctxt.user);
2950 break;
2951 case Audit_not_equal:
2952 match = (ctxt->user != rule->au_ctxt.user);
2953 break;
2954 }
2955 break;
2956 case AUDIT_SUBJ_ROLE:
2957 case AUDIT_OBJ_ROLE:
2958 switch (op) {
2959 case Audit_equal:
2960 match = (ctxt->role == rule->au_ctxt.role);
2961 break;
2962 case Audit_not_equal:
2963 match = (ctxt->role != rule->au_ctxt.role);
2964 break;
2965 }
2966 break;
2967 case AUDIT_SUBJ_TYPE:
2968 case AUDIT_OBJ_TYPE:
2969 switch (op) {
2970 case Audit_equal:
2971 match = (ctxt->type == rule->au_ctxt.type);
2972 break;
2973 case Audit_not_equal:
2974 match = (ctxt->type != rule->au_ctxt.type);
2975 break;
2976 }
2977 break;
2978 case AUDIT_SUBJ_SEN:
2979 case AUDIT_SUBJ_CLR:
2980 case AUDIT_OBJ_LEV_LOW:
2981 case AUDIT_OBJ_LEV_HIGH:
2982 level = ((field == AUDIT_SUBJ_SEN ||
2983 field == AUDIT_OBJ_LEV_LOW) ?
2984 &ctxt->range.level[0] : &ctxt->range.level[1]);
2985 switch (op) {
2986 case Audit_equal:
2987 match = mls_level_eq(&rule->au_ctxt.range.level[0],
2988 level);
2989 break;
2990 case Audit_not_equal:
2991 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2992 level);
2993 break;
2994 case Audit_lt:
2995 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2996 level) &&
2997 !mls_level_eq(&rule->au_ctxt.range.level[0],
2998 level));
2999 break;
3000 case Audit_le:
3001 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3002 level);
3003 break;
3004 case Audit_gt:
3005 match = (mls_level_dom(level,
3006 &rule->au_ctxt.range.level[0]) &&
3007 !mls_level_eq(level,
3008 &rule->au_ctxt.range.level[0]));
3009 break;
3010 case Audit_ge:
3011 match = mls_level_dom(level,
3012 &rule->au_ctxt.range.level[0]);
3013 break;
3014 }
3015 }
3016
3017out:
3018 read_unlock(&policy_rwlock);
3019 return match;
3020}
3021
3022static int (*aurule_callback)(void) = audit_update_lsm_rules;
3023
3024static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
3025 u16 class, u32 perms, u32 *retained)
3026{
3027 int err = 0;
3028
3029 if (event == AVC_CALLBACK_RESET && aurule_callback)
3030 err = aurule_callback();
3031 return err;
3032}
3033
3034static int __init aurule_init(void)
3035{
3036 int err;
3037
3038 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
3039 SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
3040 if (err)
3041 panic("avc_add_callback() failed, error %d\n", err);
3042
3043 return err;
3044}
3045__initcall(aurule_init);
3046
3047#ifdef CONFIG_NETLABEL
3048/**
3049 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3050 * @secattr: the NetLabel packet security attributes
3051 * @sid: the SELinux SID
3052 *
3053 * Description:
3054 * Attempt to cache the context in @ctx, which was derived from the packet in
3055 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3056 * already been initialized.
3057 *
3058 */
3059static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3060 u32 sid)
3061{
3062 u32 *sid_cache;
3063
3064 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3065 if (sid_cache == NULL)
3066 return;
3067 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3068 if (secattr->cache == NULL) {
3069 kfree(sid_cache);
3070 return;
3071 }
3072
3073 *sid_cache = sid;
3074 secattr->cache->free = kfree;
3075 secattr->cache->data = sid_cache;
3076 secattr->flags |= NETLBL_SECATTR_CACHE;
3077}
3078
3079/**
3080 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3081 * @secattr: the NetLabel packet security attributes
3082 * @sid: the SELinux SID
3083 *
3084 * Description:
3085 * Convert the given NetLabel security attributes in @secattr into a
3086 * SELinux SID. If the @secattr field does not contain a full SELinux
3087 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3088 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3089 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3090 * conversion for future lookups. Returns zero on success, negative values on
3091 * failure.
3092 *
3093 */
3094int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3095 u32 *sid)
3096{
3097 int rc;
3098 struct context *ctx;
3099 struct context ctx_new;
3100
3101 if (!ss_initialized) {
3102 *sid = SECSID_NULL;
3103 return 0;
3104 }
3105
3106 read_lock(&policy_rwlock);
3107
3108 if (secattr->flags & NETLBL_SECATTR_CACHE)
3109 *sid = *(u32 *)secattr->cache->data;
3110 else if (secattr->flags & NETLBL_SECATTR_SECID)
3111 *sid = secattr->attr.secid;
3112 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3113 rc = -EIDRM;
3114 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3115 if (ctx == NULL)
3116 goto out;
3117
3118 context_init(&ctx_new);
3119 ctx_new.user = ctx->user;
3120 ctx_new.role = ctx->role;
3121 ctx_new.type = ctx->type;
3122 mls_import_netlbl_lvl(&ctx_new, secattr);
3123 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3124 rc = ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
3125 secattr->attr.mls.cat);
3126 if (rc)
3127 goto out;
3128 memcpy(&ctx_new.range.level[1].cat,
3129 &ctx_new.range.level[0].cat,
3130 sizeof(ctx_new.range.level[0].cat));
3131 }
3132 rc = -EIDRM;
3133 if (!mls_context_isvalid(&policydb, &ctx_new))
3134 goto out_free;
3135
3136 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3137 if (rc)
3138 goto out_free;
3139
3140 security_netlbl_cache_add(secattr, *sid);
3141
3142 ebitmap_destroy(&ctx_new.range.level[0].cat);
3143 } else
3144 *sid = SECSID_NULL;
3145
3146 read_unlock(&policy_rwlock);
3147 return 0;
3148out_free:
3149 ebitmap_destroy(&ctx_new.range.level[0].cat);
3150out:
3151 read_unlock(&policy_rwlock);
3152 return rc;
3153}
3154
3155/**
3156 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3157 * @sid: the SELinux SID
3158 * @secattr: the NetLabel packet security attributes
3159 *
3160 * Description:
3161 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3162 * Returns zero on success, negative values on failure.
3163 *
3164 */
3165int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3166{
3167 int rc;
3168 struct context *ctx;
3169
3170 if (!ss_initialized)
3171 return 0;
3172
3173 read_lock(&policy_rwlock);
3174
3175 rc = -ENOENT;
3176 ctx = sidtab_search(&sidtab, sid);
3177 if (ctx == NULL)
3178 goto out;
3179
3180 rc = -ENOMEM;
3181 secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1),
3182 GFP_ATOMIC);
3183 if (secattr->domain == NULL)
3184 goto out;
3185
3186 secattr->attr.secid = sid;
3187 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3188 mls_export_netlbl_lvl(ctx, secattr);
3189 rc = mls_export_netlbl_cat(ctx, secattr);
3190out:
3191 read_unlock(&policy_rwlock);
3192 return rc;
3193}
3194#endif /* CONFIG_NETLABEL */
3195
3196/**
3197 * security_read_policy - read the policy.
3198 * @data: binary policy data
3199 * @len: length of data in bytes
3200 *
3201 */
3202int security_read_policy(void **data, size_t *len)
3203{
3204 int rc;
3205 struct policy_file fp;
3206
3207 if (!ss_initialized)
3208 return -EINVAL;
3209
3210 *len = security_policydb_len();
3211
3212 *data = vmalloc_user(*len);
3213 if (!*data)
3214 return -ENOMEM;
3215
3216 fp.data = *data;
3217 fp.len = *len;
3218
3219 read_lock(&policy_rwlock);
3220 rc = policydb_write(&policydb, &fp);
3221 read_unlock(&policy_rwlock);
3222
3223 if (rc)
3224 return rc;
3225
3226 *len = (unsigned long)fp.data - (unsigned long)*data;
3227 return 0;
3228
3229}
1/*
2 * Implementation of the security services.
3 *
4 * Authors : Stephen Smalley, <sds@tycho.nsa.gov>
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@paul-moore.com>
17 *
18 * Added support for NetLabel
19 * Added support for the policy capability bitmap
20 *
21 * Updated: Chad Sellers <csellers@tresys.com>
22 *
23 * Added validation of kernel classes and permissions
24 *
25 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
26 *
27 * Added support for bounds domain and audit messaged on masked permissions
28 *
29 * Updated: Guido Trentalancia <guido@trentalancia.com>
30 *
31 * Added support for runtime switching of the policy type
32 *
33 * Copyright (C) 2008, 2009 NEC Corporation
34 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
35 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
36 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
37 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
38 * This program is free software; you can redistribute it and/or modify
39 * it under the terms of the GNU General Public License as published by
40 * the Free Software Foundation, version 2.
41 */
42#include <linux/kernel.h>
43#include <linux/slab.h>
44#include <linux/string.h>
45#include <linux/spinlock.h>
46#include <linux/rcupdate.h>
47#include <linux/errno.h>
48#include <linux/in.h>
49#include <linux/sched.h>
50#include <linux/audit.h>
51#include <linux/mutex.h>
52#include <linux/selinux.h>
53#include <linux/flex_array.h>
54#include <linux/vmalloc.h>
55#include <net/netlabel.h>
56
57#include "flask.h"
58#include "avc.h"
59#include "avc_ss.h"
60#include "security.h"
61#include "context.h"
62#include "policydb.h"
63#include "sidtab.h"
64#include "services.h"
65#include "conditional.h"
66#include "mls.h"
67#include "objsec.h"
68#include "netlabel.h"
69#include "xfrm.h"
70#include "ebitmap.h"
71#include "audit.h"
72
73/* Policy capability names */
74char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = {
75 "network_peer_controls",
76 "open_perms",
77 "extended_socket_class",
78 "always_check_network",
79 "cgroup_seclabel",
80 "nnp_nosuid_transition"
81};
82
83static struct selinux_ss selinux_ss;
84
85void selinux_ss_init(struct selinux_ss **ss)
86{
87 rwlock_init(&selinux_ss.policy_rwlock);
88 mutex_init(&selinux_ss.status_lock);
89 *ss = &selinux_ss;
90}
91
92/* Forward declaration. */
93static int context_struct_to_string(struct policydb *policydb,
94 struct context *context,
95 char **scontext,
96 u32 *scontext_len);
97
98static void context_struct_compute_av(struct policydb *policydb,
99 struct context *scontext,
100 struct context *tcontext,
101 u16 tclass,
102 struct av_decision *avd,
103 struct extended_perms *xperms);
104
105static int selinux_set_mapping(struct policydb *pol,
106 struct security_class_mapping *map,
107 struct selinux_map *out_map)
108{
109 u16 i, j;
110 unsigned k;
111 bool print_unknown_handle = false;
112
113 /* Find number of classes in the input mapping */
114 if (!map)
115 return -EINVAL;
116 i = 0;
117 while (map[i].name)
118 i++;
119
120 /* Allocate space for the class records, plus one for class zero */
121 out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC);
122 if (!out_map->mapping)
123 return -ENOMEM;
124
125 /* Store the raw class and permission values */
126 j = 0;
127 while (map[j].name) {
128 struct security_class_mapping *p_in = map + (j++);
129 struct selinux_mapping *p_out = out_map->mapping + j;
130
131 /* An empty class string skips ahead */
132 if (!strcmp(p_in->name, "")) {
133 p_out->num_perms = 0;
134 continue;
135 }
136
137 p_out->value = string_to_security_class(pol, p_in->name);
138 if (!p_out->value) {
139 printk(KERN_INFO
140 "SELinux: Class %s not defined in policy.\n",
141 p_in->name);
142 if (pol->reject_unknown)
143 goto err;
144 p_out->num_perms = 0;
145 print_unknown_handle = true;
146 continue;
147 }
148
149 k = 0;
150 while (p_in->perms[k]) {
151 /* An empty permission string skips ahead */
152 if (!*p_in->perms[k]) {
153 k++;
154 continue;
155 }
156 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
157 p_in->perms[k]);
158 if (!p_out->perms[k]) {
159 printk(KERN_INFO
160 "SELinux: Permission %s in class %s not defined in policy.\n",
161 p_in->perms[k], p_in->name);
162 if (pol->reject_unknown)
163 goto err;
164 print_unknown_handle = true;
165 }
166
167 k++;
168 }
169 p_out->num_perms = k;
170 }
171
172 if (print_unknown_handle)
173 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
174 pol->allow_unknown ? "allowed" : "denied");
175
176 out_map->size = i;
177 return 0;
178err:
179 kfree(out_map->mapping);
180 out_map->mapping = NULL;
181 return -EINVAL;
182}
183
184/*
185 * Get real, policy values from mapped values
186 */
187
188static u16 unmap_class(struct selinux_map *map, u16 tclass)
189{
190 if (tclass < map->size)
191 return map->mapping[tclass].value;
192
193 return tclass;
194}
195
196/*
197 * Get kernel value for class from its policy value
198 */
199static u16 map_class(struct selinux_map *map, u16 pol_value)
200{
201 u16 i;
202
203 for (i = 1; i < map->size; i++) {
204 if (map->mapping[i].value == pol_value)
205 return i;
206 }
207
208 return SECCLASS_NULL;
209}
210
211static void map_decision(struct selinux_map *map,
212 u16 tclass, struct av_decision *avd,
213 int allow_unknown)
214{
215 if (tclass < map->size) {
216 struct selinux_mapping *mapping = &map->mapping[tclass];
217 unsigned int i, n = mapping->num_perms;
218 u32 result;
219
220 for (i = 0, result = 0; i < n; i++) {
221 if (avd->allowed & mapping->perms[i])
222 result |= 1<<i;
223 if (allow_unknown && !mapping->perms[i])
224 result |= 1<<i;
225 }
226 avd->allowed = result;
227
228 for (i = 0, result = 0; i < n; i++)
229 if (avd->auditallow & mapping->perms[i])
230 result |= 1<<i;
231 avd->auditallow = result;
232
233 for (i = 0, result = 0; i < n; i++) {
234 if (avd->auditdeny & mapping->perms[i])
235 result |= 1<<i;
236 if (!allow_unknown && !mapping->perms[i])
237 result |= 1<<i;
238 }
239 /*
240 * In case the kernel has a bug and requests a permission
241 * between num_perms and the maximum permission number, we
242 * should audit that denial
243 */
244 for (; i < (sizeof(u32)*8); i++)
245 result |= 1<<i;
246 avd->auditdeny = result;
247 }
248}
249
250int security_mls_enabled(struct selinux_state *state)
251{
252 struct policydb *p = &state->ss->policydb;
253
254 return p->mls_enabled;
255}
256
257/*
258 * Return the boolean value of a constraint expression
259 * when it is applied to the specified source and target
260 * security contexts.
261 *
262 * xcontext is a special beast... It is used by the validatetrans rules
263 * only. For these rules, scontext is the context before the transition,
264 * tcontext is the context after the transition, and xcontext is the context
265 * of the process performing the transition. All other callers of
266 * constraint_expr_eval should pass in NULL for xcontext.
267 */
268static int constraint_expr_eval(struct policydb *policydb,
269 struct context *scontext,
270 struct context *tcontext,
271 struct context *xcontext,
272 struct constraint_expr *cexpr)
273{
274 u32 val1, val2;
275 struct context *c;
276 struct role_datum *r1, *r2;
277 struct mls_level *l1, *l2;
278 struct constraint_expr *e;
279 int s[CEXPR_MAXDEPTH];
280 int sp = -1;
281
282 for (e = cexpr; e; e = e->next) {
283 switch (e->expr_type) {
284 case CEXPR_NOT:
285 BUG_ON(sp < 0);
286 s[sp] = !s[sp];
287 break;
288 case CEXPR_AND:
289 BUG_ON(sp < 1);
290 sp--;
291 s[sp] &= s[sp + 1];
292 break;
293 case CEXPR_OR:
294 BUG_ON(sp < 1);
295 sp--;
296 s[sp] |= s[sp + 1];
297 break;
298 case CEXPR_ATTR:
299 if (sp == (CEXPR_MAXDEPTH - 1))
300 return 0;
301 switch (e->attr) {
302 case CEXPR_USER:
303 val1 = scontext->user;
304 val2 = tcontext->user;
305 break;
306 case CEXPR_TYPE:
307 val1 = scontext->type;
308 val2 = tcontext->type;
309 break;
310 case CEXPR_ROLE:
311 val1 = scontext->role;
312 val2 = tcontext->role;
313 r1 = policydb->role_val_to_struct[val1 - 1];
314 r2 = policydb->role_val_to_struct[val2 - 1];
315 switch (e->op) {
316 case CEXPR_DOM:
317 s[++sp] = ebitmap_get_bit(&r1->dominates,
318 val2 - 1);
319 continue;
320 case CEXPR_DOMBY:
321 s[++sp] = ebitmap_get_bit(&r2->dominates,
322 val1 - 1);
323 continue;
324 case CEXPR_INCOMP:
325 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
326 val2 - 1) &&
327 !ebitmap_get_bit(&r2->dominates,
328 val1 - 1));
329 continue;
330 default:
331 break;
332 }
333 break;
334 case CEXPR_L1L2:
335 l1 = &(scontext->range.level[0]);
336 l2 = &(tcontext->range.level[0]);
337 goto mls_ops;
338 case CEXPR_L1H2:
339 l1 = &(scontext->range.level[0]);
340 l2 = &(tcontext->range.level[1]);
341 goto mls_ops;
342 case CEXPR_H1L2:
343 l1 = &(scontext->range.level[1]);
344 l2 = &(tcontext->range.level[0]);
345 goto mls_ops;
346 case CEXPR_H1H2:
347 l1 = &(scontext->range.level[1]);
348 l2 = &(tcontext->range.level[1]);
349 goto mls_ops;
350 case CEXPR_L1H1:
351 l1 = &(scontext->range.level[0]);
352 l2 = &(scontext->range.level[1]);
353 goto mls_ops;
354 case CEXPR_L2H2:
355 l1 = &(tcontext->range.level[0]);
356 l2 = &(tcontext->range.level[1]);
357 goto mls_ops;
358mls_ops:
359 switch (e->op) {
360 case CEXPR_EQ:
361 s[++sp] = mls_level_eq(l1, l2);
362 continue;
363 case CEXPR_NEQ:
364 s[++sp] = !mls_level_eq(l1, l2);
365 continue;
366 case CEXPR_DOM:
367 s[++sp] = mls_level_dom(l1, l2);
368 continue;
369 case CEXPR_DOMBY:
370 s[++sp] = mls_level_dom(l2, l1);
371 continue;
372 case CEXPR_INCOMP:
373 s[++sp] = mls_level_incomp(l2, l1);
374 continue;
375 default:
376 BUG();
377 return 0;
378 }
379 break;
380 default:
381 BUG();
382 return 0;
383 }
384
385 switch (e->op) {
386 case CEXPR_EQ:
387 s[++sp] = (val1 == val2);
388 break;
389 case CEXPR_NEQ:
390 s[++sp] = (val1 != val2);
391 break;
392 default:
393 BUG();
394 return 0;
395 }
396 break;
397 case CEXPR_NAMES:
398 if (sp == (CEXPR_MAXDEPTH-1))
399 return 0;
400 c = scontext;
401 if (e->attr & CEXPR_TARGET)
402 c = tcontext;
403 else if (e->attr & CEXPR_XTARGET) {
404 c = xcontext;
405 if (!c) {
406 BUG();
407 return 0;
408 }
409 }
410 if (e->attr & CEXPR_USER)
411 val1 = c->user;
412 else if (e->attr & CEXPR_ROLE)
413 val1 = c->role;
414 else if (e->attr & CEXPR_TYPE)
415 val1 = c->type;
416 else {
417 BUG();
418 return 0;
419 }
420
421 switch (e->op) {
422 case CEXPR_EQ:
423 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
424 break;
425 case CEXPR_NEQ:
426 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
427 break;
428 default:
429 BUG();
430 return 0;
431 }
432 break;
433 default:
434 BUG();
435 return 0;
436 }
437 }
438
439 BUG_ON(sp != 0);
440 return s[0];
441}
442
443/*
444 * security_dump_masked_av - dumps masked permissions during
445 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
446 */
447static int dump_masked_av_helper(void *k, void *d, void *args)
448{
449 struct perm_datum *pdatum = d;
450 char **permission_names = args;
451
452 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
453
454 permission_names[pdatum->value - 1] = (char *)k;
455
456 return 0;
457}
458
459static void security_dump_masked_av(struct policydb *policydb,
460 struct context *scontext,
461 struct context *tcontext,
462 u16 tclass,
463 u32 permissions,
464 const char *reason)
465{
466 struct common_datum *common_dat;
467 struct class_datum *tclass_dat;
468 struct audit_buffer *ab;
469 char *tclass_name;
470 char *scontext_name = NULL;
471 char *tcontext_name = NULL;
472 char *permission_names[32];
473 int index;
474 u32 length;
475 bool need_comma = false;
476
477 if (!permissions)
478 return;
479
480 tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1);
481 tclass_dat = policydb->class_val_to_struct[tclass - 1];
482 common_dat = tclass_dat->comdatum;
483
484 /* init permission_names */
485 if (common_dat &&
486 hashtab_map(common_dat->permissions.table,
487 dump_masked_av_helper, permission_names) < 0)
488 goto out;
489
490 if (hashtab_map(tclass_dat->permissions.table,
491 dump_masked_av_helper, permission_names) < 0)
492 goto out;
493
494 /* get scontext/tcontext in text form */
495 if (context_struct_to_string(policydb, scontext,
496 &scontext_name, &length) < 0)
497 goto out;
498
499 if (context_struct_to_string(policydb, tcontext,
500 &tcontext_name, &length) < 0)
501 goto out;
502
503 /* audit a message */
504 ab = audit_log_start(current->audit_context,
505 GFP_ATOMIC, AUDIT_SELINUX_ERR);
506 if (!ab)
507 goto out;
508
509 audit_log_format(ab, "op=security_compute_av reason=%s "
510 "scontext=%s tcontext=%s tclass=%s perms=",
511 reason, scontext_name, tcontext_name, tclass_name);
512
513 for (index = 0; index < 32; index++) {
514 u32 mask = (1 << index);
515
516 if ((mask & permissions) == 0)
517 continue;
518
519 audit_log_format(ab, "%s%s",
520 need_comma ? "," : "",
521 permission_names[index]
522 ? permission_names[index] : "????");
523 need_comma = true;
524 }
525 audit_log_end(ab);
526out:
527 /* release scontext/tcontext */
528 kfree(tcontext_name);
529 kfree(scontext_name);
530
531 return;
532}
533
534/*
535 * security_boundary_permission - drops violated permissions
536 * on boundary constraint.
537 */
538static void type_attribute_bounds_av(struct policydb *policydb,
539 struct context *scontext,
540 struct context *tcontext,
541 u16 tclass,
542 struct av_decision *avd)
543{
544 struct context lo_scontext;
545 struct context lo_tcontext, *tcontextp = tcontext;
546 struct av_decision lo_avd;
547 struct type_datum *source;
548 struct type_datum *target;
549 u32 masked = 0;
550
551 source = flex_array_get_ptr(policydb->type_val_to_struct_array,
552 scontext->type - 1);
553 BUG_ON(!source);
554
555 if (!source->bounds)
556 return;
557
558 target = flex_array_get_ptr(policydb->type_val_to_struct_array,
559 tcontext->type - 1);
560 BUG_ON(!target);
561
562 memset(&lo_avd, 0, sizeof(lo_avd));
563
564 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
565 lo_scontext.type = source->bounds;
566
567 if (target->bounds) {
568 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
569 lo_tcontext.type = target->bounds;
570 tcontextp = &lo_tcontext;
571 }
572
573 context_struct_compute_av(policydb, &lo_scontext,
574 tcontextp,
575 tclass,
576 &lo_avd,
577 NULL);
578
579 masked = ~lo_avd.allowed & avd->allowed;
580
581 if (likely(!masked))
582 return; /* no masked permission */
583
584 /* mask violated permissions */
585 avd->allowed &= ~masked;
586
587 /* audit masked permissions */
588 security_dump_masked_av(policydb, scontext, tcontext,
589 tclass, masked, "bounds");
590}
591
592/*
593 * flag which drivers have permissions
594 * only looking for ioctl based extended permssions
595 */
596void services_compute_xperms_drivers(
597 struct extended_perms *xperms,
598 struct avtab_node *node)
599{
600 unsigned int i;
601
602 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
603 /* if one or more driver has all permissions allowed */
604 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++)
605 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i];
606 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
607 /* if allowing permissions within a driver */
608 security_xperm_set(xperms->drivers.p,
609 node->datum.u.xperms->driver);
610 }
611
612 /* If no ioctl commands are allowed, ignore auditallow and auditdeny */
613 if (node->key.specified & AVTAB_XPERMS_ALLOWED)
614 xperms->len = 1;
615}
616
617/*
618 * Compute access vectors and extended permissions based on a context
619 * structure pair for the permissions in a particular class.
620 */
621static void context_struct_compute_av(struct policydb *policydb,
622 struct context *scontext,
623 struct context *tcontext,
624 u16 tclass,
625 struct av_decision *avd,
626 struct extended_perms *xperms)
627{
628 struct constraint_node *constraint;
629 struct role_allow *ra;
630 struct avtab_key avkey;
631 struct avtab_node *node;
632 struct class_datum *tclass_datum;
633 struct ebitmap *sattr, *tattr;
634 struct ebitmap_node *snode, *tnode;
635 unsigned int i, j;
636
637 avd->allowed = 0;
638 avd->auditallow = 0;
639 avd->auditdeny = 0xffffffff;
640 if (xperms) {
641 memset(&xperms->drivers, 0, sizeof(xperms->drivers));
642 xperms->len = 0;
643 }
644
645 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
646 if (printk_ratelimit())
647 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass);
648 return;
649 }
650
651 tclass_datum = policydb->class_val_to_struct[tclass - 1];
652
653 /*
654 * If a specific type enforcement rule was defined for
655 * this permission check, then use it.
656 */
657 avkey.target_class = tclass;
658 avkey.specified = AVTAB_AV | AVTAB_XPERMS;
659 sattr = flex_array_get(policydb->type_attr_map_array,
660 scontext->type - 1);
661 BUG_ON(!sattr);
662 tattr = flex_array_get(policydb->type_attr_map_array,
663 tcontext->type - 1);
664 BUG_ON(!tattr);
665 ebitmap_for_each_positive_bit(sattr, snode, i) {
666 ebitmap_for_each_positive_bit(tattr, tnode, j) {
667 avkey.source_type = i + 1;
668 avkey.target_type = j + 1;
669 for (node = avtab_search_node(&policydb->te_avtab,
670 &avkey);
671 node;
672 node = avtab_search_node_next(node, avkey.specified)) {
673 if (node->key.specified == AVTAB_ALLOWED)
674 avd->allowed |= node->datum.u.data;
675 else if (node->key.specified == AVTAB_AUDITALLOW)
676 avd->auditallow |= node->datum.u.data;
677 else if (node->key.specified == AVTAB_AUDITDENY)
678 avd->auditdeny &= node->datum.u.data;
679 else if (xperms && (node->key.specified & AVTAB_XPERMS))
680 services_compute_xperms_drivers(xperms, node);
681 }
682
683 /* Check conditional av table for additional permissions */
684 cond_compute_av(&policydb->te_cond_avtab, &avkey,
685 avd, xperms);
686
687 }
688 }
689
690 /*
691 * Remove any permissions prohibited by a constraint (this includes
692 * the MLS policy).
693 */
694 constraint = tclass_datum->constraints;
695 while (constraint) {
696 if ((constraint->permissions & (avd->allowed)) &&
697 !constraint_expr_eval(policydb, scontext, tcontext, NULL,
698 constraint->expr)) {
699 avd->allowed &= ~(constraint->permissions);
700 }
701 constraint = constraint->next;
702 }
703
704 /*
705 * If checking process transition permission and the
706 * role is changing, then check the (current_role, new_role)
707 * pair.
708 */
709 if (tclass == policydb->process_class &&
710 (avd->allowed & policydb->process_trans_perms) &&
711 scontext->role != tcontext->role) {
712 for (ra = policydb->role_allow; ra; ra = ra->next) {
713 if (scontext->role == ra->role &&
714 tcontext->role == ra->new_role)
715 break;
716 }
717 if (!ra)
718 avd->allowed &= ~policydb->process_trans_perms;
719 }
720
721 /*
722 * If the given source and target types have boundary
723 * constraint, lazy checks have to mask any violated
724 * permission and notice it to userspace via audit.
725 */
726 type_attribute_bounds_av(policydb, scontext, tcontext,
727 tclass, avd);
728}
729
730static int security_validtrans_handle_fail(struct selinux_state *state,
731 struct context *ocontext,
732 struct context *ncontext,
733 struct context *tcontext,
734 u16 tclass)
735{
736 struct policydb *p = &state->ss->policydb;
737 char *o = NULL, *n = NULL, *t = NULL;
738 u32 olen, nlen, tlen;
739
740 if (context_struct_to_string(p, ocontext, &o, &olen))
741 goto out;
742 if (context_struct_to_string(p, ncontext, &n, &nlen))
743 goto out;
744 if (context_struct_to_string(p, tcontext, &t, &tlen))
745 goto out;
746 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
747 "op=security_validate_transition seresult=denied"
748 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
749 o, n, t, sym_name(p, SYM_CLASSES, tclass-1));
750out:
751 kfree(o);
752 kfree(n);
753 kfree(t);
754
755 if (!enforcing_enabled(state))
756 return 0;
757 return -EPERM;
758}
759
760static int security_compute_validatetrans(struct selinux_state *state,
761 u32 oldsid, u32 newsid, u32 tasksid,
762 u16 orig_tclass, bool user)
763{
764 struct policydb *policydb;
765 struct sidtab *sidtab;
766 struct context *ocontext;
767 struct context *ncontext;
768 struct context *tcontext;
769 struct class_datum *tclass_datum;
770 struct constraint_node *constraint;
771 u16 tclass;
772 int rc = 0;
773
774
775 if (!state->initialized)
776 return 0;
777
778 read_lock(&state->ss->policy_rwlock);
779
780 policydb = &state->ss->policydb;
781 sidtab = &state->ss->sidtab;
782
783 if (!user)
784 tclass = unmap_class(&state->ss->map, orig_tclass);
785 else
786 tclass = orig_tclass;
787
788 if (!tclass || tclass > policydb->p_classes.nprim) {
789 rc = -EINVAL;
790 goto out;
791 }
792 tclass_datum = policydb->class_val_to_struct[tclass - 1];
793
794 ocontext = sidtab_search(sidtab, oldsid);
795 if (!ocontext) {
796 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
797 __func__, oldsid);
798 rc = -EINVAL;
799 goto out;
800 }
801
802 ncontext = sidtab_search(sidtab, newsid);
803 if (!ncontext) {
804 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
805 __func__, newsid);
806 rc = -EINVAL;
807 goto out;
808 }
809
810 tcontext = sidtab_search(sidtab, tasksid);
811 if (!tcontext) {
812 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
813 __func__, tasksid);
814 rc = -EINVAL;
815 goto out;
816 }
817
818 constraint = tclass_datum->validatetrans;
819 while (constraint) {
820 if (!constraint_expr_eval(policydb, ocontext, ncontext,
821 tcontext, constraint->expr)) {
822 if (user)
823 rc = -EPERM;
824 else
825 rc = security_validtrans_handle_fail(state,
826 ocontext,
827 ncontext,
828 tcontext,
829 tclass);
830 goto out;
831 }
832 constraint = constraint->next;
833 }
834
835out:
836 read_unlock(&state->ss->policy_rwlock);
837 return rc;
838}
839
840int security_validate_transition_user(struct selinux_state *state,
841 u32 oldsid, u32 newsid, u32 tasksid,
842 u16 tclass)
843{
844 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
845 tclass, true);
846}
847
848int security_validate_transition(struct selinux_state *state,
849 u32 oldsid, u32 newsid, u32 tasksid,
850 u16 orig_tclass)
851{
852 return security_compute_validatetrans(state, oldsid, newsid, tasksid,
853 orig_tclass, false);
854}
855
856/*
857 * security_bounded_transition - check whether the given
858 * transition is directed to bounded, or not.
859 * It returns 0, if @newsid is bounded by @oldsid.
860 * Otherwise, it returns error code.
861 *
862 * @oldsid : current security identifier
863 * @newsid : destinated security identifier
864 */
865int security_bounded_transition(struct selinux_state *state,
866 u32 old_sid, u32 new_sid)
867{
868 struct policydb *policydb;
869 struct sidtab *sidtab;
870 struct context *old_context, *new_context;
871 struct type_datum *type;
872 int index;
873 int rc;
874
875 if (!state->initialized)
876 return 0;
877
878 read_lock(&state->ss->policy_rwlock);
879
880 policydb = &state->ss->policydb;
881 sidtab = &state->ss->sidtab;
882
883 rc = -EINVAL;
884 old_context = sidtab_search(sidtab, old_sid);
885 if (!old_context) {
886 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
887 __func__, old_sid);
888 goto out;
889 }
890
891 rc = -EINVAL;
892 new_context = sidtab_search(sidtab, new_sid);
893 if (!new_context) {
894 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
895 __func__, new_sid);
896 goto out;
897 }
898
899 rc = 0;
900 /* type/domain unchanged */
901 if (old_context->type == new_context->type)
902 goto out;
903
904 index = new_context->type;
905 while (true) {
906 type = flex_array_get_ptr(policydb->type_val_to_struct_array,
907 index - 1);
908 BUG_ON(!type);
909
910 /* not bounded anymore */
911 rc = -EPERM;
912 if (!type->bounds)
913 break;
914
915 /* @newsid is bounded by @oldsid */
916 rc = 0;
917 if (type->bounds == old_context->type)
918 break;
919
920 index = type->bounds;
921 }
922
923 if (rc) {
924 char *old_name = NULL;
925 char *new_name = NULL;
926 u32 length;
927
928 if (!context_struct_to_string(policydb, old_context,
929 &old_name, &length) &&
930 !context_struct_to_string(policydb, new_context,
931 &new_name, &length)) {
932 audit_log(current->audit_context,
933 GFP_ATOMIC, AUDIT_SELINUX_ERR,
934 "op=security_bounded_transition "
935 "seresult=denied "
936 "oldcontext=%s newcontext=%s",
937 old_name, new_name);
938 }
939 kfree(new_name);
940 kfree(old_name);
941 }
942out:
943 read_unlock(&state->ss->policy_rwlock);
944
945 return rc;
946}
947
948static void avd_init(struct selinux_state *state, struct av_decision *avd)
949{
950 avd->allowed = 0;
951 avd->auditallow = 0;
952 avd->auditdeny = 0xffffffff;
953 avd->seqno = state->ss->latest_granting;
954 avd->flags = 0;
955}
956
957void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
958 struct avtab_node *node)
959{
960 unsigned int i;
961
962 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
963 if (xpermd->driver != node->datum.u.xperms->driver)
964 return;
965 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
966 if (!security_xperm_test(node->datum.u.xperms->perms.p,
967 xpermd->driver))
968 return;
969 } else {
970 BUG();
971 }
972
973 if (node->key.specified == AVTAB_XPERMS_ALLOWED) {
974 xpermd->used |= XPERMS_ALLOWED;
975 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
976 memset(xpermd->allowed->p, 0xff,
977 sizeof(xpermd->allowed->p));
978 }
979 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
980 for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++)
981 xpermd->allowed->p[i] |=
982 node->datum.u.xperms->perms.p[i];
983 }
984 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) {
985 xpermd->used |= XPERMS_AUDITALLOW;
986 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
987 memset(xpermd->auditallow->p, 0xff,
988 sizeof(xpermd->auditallow->p));
989 }
990 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
991 for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++)
992 xpermd->auditallow->p[i] |=
993 node->datum.u.xperms->perms.p[i];
994 }
995 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) {
996 xpermd->used |= XPERMS_DONTAUDIT;
997 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) {
998 memset(xpermd->dontaudit->p, 0xff,
999 sizeof(xpermd->dontaudit->p));
1000 }
1001 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) {
1002 for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++)
1003 xpermd->dontaudit->p[i] |=
1004 node->datum.u.xperms->perms.p[i];
1005 }
1006 } else {
1007 BUG();
1008 }
1009}
1010
1011void security_compute_xperms_decision(struct selinux_state *state,
1012 u32 ssid,
1013 u32 tsid,
1014 u16 orig_tclass,
1015 u8 driver,
1016 struct extended_perms_decision *xpermd)
1017{
1018 struct policydb *policydb;
1019 struct sidtab *sidtab;
1020 u16 tclass;
1021 struct context *scontext, *tcontext;
1022 struct avtab_key avkey;
1023 struct avtab_node *node;
1024 struct ebitmap *sattr, *tattr;
1025 struct ebitmap_node *snode, *tnode;
1026 unsigned int i, j;
1027
1028 xpermd->driver = driver;
1029 xpermd->used = 0;
1030 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p));
1031 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p));
1032 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p));
1033
1034 read_lock(&state->ss->policy_rwlock);
1035 if (!state->initialized)
1036 goto allow;
1037
1038 policydb = &state->ss->policydb;
1039 sidtab = &state->ss->sidtab;
1040
1041 scontext = sidtab_search(sidtab, ssid);
1042 if (!scontext) {
1043 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1044 __func__, ssid);
1045 goto out;
1046 }
1047
1048 tcontext = sidtab_search(sidtab, tsid);
1049 if (!tcontext) {
1050 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1051 __func__, tsid);
1052 goto out;
1053 }
1054
1055 tclass = unmap_class(&state->ss->map, orig_tclass);
1056 if (unlikely(orig_tclass && !tclass)) {
1057 if (policydb->allow_unknown)
1058 goto allow;
1059 goto out;
1060 }
1061
1062
1063 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) {
1064 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass);
1065 goto out;
1066 }
1067
1068 avkey.target_class = tclass;
1069 avkey.specified = AVTAB_XPERMS;
1070 sattr = flex_array_get(policydb->type_attr_map_array,
1071 scontext->type - 1);
1072 BUG_ON(!sattr);
1073 tattr = flex_array_get(policydb->type_attr_map_array,
1074 tcontext->type - 1);
1075 BUG_ON(!tattr);
1076 ebitmap_for_each_positive_bit(sattr, snode, i) {
1077 ebitmap_for_each_positive_bit(tattr, tnode, j) {
1078 avkey.source_type = i + 1;
1079 avkey.target_type = j + 1;
1080 for (node = avtab_search_node(&policydb->te_avtab,
1081 &avkey);
1082 node;
1083 node = avtab_search_node_next(node, avkey.specified))
1084 services_compute_xperms_decision(xpermd, node);
1085
1086 cond_compute_xperms(&policydb->te_cond_avtab,
1087 &avkey, xpermd);
1088 }
1089 }
1090out:
1091 read_unlock(&state->ss->policy_rwlock);
1092 return;
1093allow:
1094 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p));
1095 goto out;
1096}
1097
1098/**
1099 * security_compute_av - Compute access vector decisions.
1100 * @ssid: source security identifier
1101 * @tsid: target security identifier
1102 * @tclass: target security class
1103 * @avd: access vector decisions
1104 * @xperms: extended permissions
1105 *
1106 * Compute a set of access vector decisions based on the
1107 * SID pair (@ssid, @tsid) for the permissions in @tclass.
1108 */
1109void security_compute_av(struct selinux_state *state,
1110 u32 ssid,
1111 u32 tsid,
1112 u16 orig_tclass,
1113 struct av_decision *avd,
1114 struct extended_perms *xperms)
1115{
1116 struct policydb *policydb;
1117 struct sidtab *sidtab;
1118 u16 tclass;
1119 struct context *scontext = NULL, *tcontext = NULL;
1120
1121 read_lock(&state->ss->policy_rwlock);
1122 avd_init(state, avd);
1123 xperms->len = 0;
1124 if (!state->initialized)
1125 goto allow;
1126
1127 policydb = &state->ss->policydb;
1128 sidtab = &state->ss->sidtab;
1129
1130 scontext = sidtab_search(sidtab, ssid);
1131 if (!scontext) {
1132 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1133 __func__, ssid);
1134 goto out;
1135 }
1136
1137 /* permissive domain? */
1138 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1139 avd->flags |= AVD_FLAGS_PERMISSIVE;
1140
1141 tcontext = sidtab_search(sidtab, tsid);
1142 if (!tcontext) {
1143 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1144 __func__, tsid);
1145 goto out;
1146 }
1147
1148 tclass = unmap_class(&state->ss->map, orig_tclass);
1149 if (unlikely(orig_tclass && !tclass)) {
1150 if (policydb->allow_unknown)
1151 goto allow;
1152 goto out;
1153 }
1154 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1155 xperms);
1156 map_decision(&state->ss->map, orig_tclass, avd,
1157 policydb->allow_unknown);
1158out:
1159 read_unlock(&state->ss->policy_rwlock);
1160 return;
1161allow:
1162 avd->allowed = 0xffffffff;
1163 goto out;
1164}
1165
1166void security_compute_av_user(struct selinux_state *state,
1167 u32 ssid,
1168 u32 tsid,
1169 u16 tclass,
1170 struct av_decision *avd)
1171{
1172 struct policydb *policydb;
1173 struct sidtab *sidtab;
1174 struct context *scontext = NULL, *tcontext = NULL;
1175
1176 read_lock(&state->ss->policy_rwlock);
1177 avd_init(state, avd);
1178 if (!state->initialized)
1179 goto allow;
1180
1181 policydb = &state->ss->policydb;
1182 sidtab = &state->ss->sidtab;
1183
1184 scontext = sidtab_search(sidtab, ssid);
1185 if (!scontext) {
1186 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1187 __func__, ssid);
1188 goto out;
1189 }
1190
1191 /* permissive domain? */
1192 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type))
1193 avd->flags |= AVD_FLAGS_PERMISSIVE;
1194
1195 tcontext = sidtab_search(sidtab, tsid);
1196 if (!tcontext) {
1197 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1198 __func__, tsid);
1199 goto out;
1200 }
1201
1202 if (unlikely(!tclass)) {
1203 if (policydb->allow_unknown)
1204 goto allow;
1205 goto out;
1206 }
1207
1208 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd,
1209 NULL);
1210 out:
1211 read_unlock(&state->ss->policy_rwlock);
1212 return;
1213allow:
1214 avd->allowed = 0xffffffff;
1215 goto out;
1216}
1217
1218/*
1219 * Write the security context string representation of
1220 * the context structure `context' into a dynamically
1221 * allocated string of the correct size. Set `*scontext'
1222 * to point to this string and set `*scontext_len' to
1223 * the length of the string.
1224 */
1225static int context_struct_to_string(struct policydb *p,
1226 struct context *context,
1227 char **scontext, u32 *scontext_len)
1228{
1229 char *scontextp;
1230
1231 if (scontext)
1232 *scontext = NULL;
1233 *scontext_len = 0;
1234
1235 if (context->len) {
1236 *scontext_len = context->len;
1237 if (scontext) {
1238 *scontext = kstrdup(context->str, GFP_ATOMIC);
1239 if (!(*scontext))
1240 return -ENOMEM;
1241 }
1242 return 0;
1243 }
1244
1245 /* Compute the size of the context. */
1246 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1;
1247 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1;
1248 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1;
1249 *scontext_len += mls_compute_context_len(p, context);
1250
1251 if (!scontext)
1252 return 0;
1253
1254 /* Allocate space for the context; caller must free this space. */
1255 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1256 if (!scontextp)
1257 return -ENOMEM;
1258 *scontext = scontextp;
1259
1260 /*
1261 * Copy the user name, role name and type name into the context.
1262 */
1263 scontextp += sprintf(scontextp, "%s:%s:%s",
1264 sym_name(p, SYM_USERS, context->user - 1),
1265 sym_name(p, SYM_ROLES, context->role - 1),
1266 sym_name(p, SYM_TYPES, context->type - 1));
1267
1268 mls_sid_to_context(p, context, &scontextp);
1269
1270 *scontextp = 0;
1271
1272 return 0;
1273}
1274
1275#include "initial_sid_to_string.h"
1276
1277const char *security_get_initial_sid_context(u32 sid)
1278{
1279 if (unlikely(sid > SECINITSID_NUM))
1280 return NULL;
1281 return initial_sid_to_string[sid];
1282}
1283
1284static int security_sid_to_context_core(struct selinux_state *state,
1285 u32 sid, char **scontext,
1286 u32 *scontext_len, int force)
1287{
1288 struct policydb *policydb;
1289 struct sidtab *sidtab;
1290 struct context *context;
1291 int rc = 0;
1292
1293 if (scontext)
1294 *scontext = NULL;
1295 *scontext_len = 0;
1296
1297 if (!state->initialized) {
1298 if (sid <= SECINITSID_NUM) {
1299 char *scontextp;
1300
1301 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1302 if (!scontext)
1303 goto out;
1304 scontextp = kmemdup(initial_sid_to_string[sid],
1305 *scontext_len, GFP_ATOMIC);
1306 if (!scontextp) {
1307 rc = -ENOMEM;
1308 goto out;
1309 }
1310 *scontext = scontextp;
1311 goto out;
1312 }
1313 printk(KERN_ERR "SELinux: %s: called before initial "
1314 "load_policy on unknown SID %d\n", __func__, sid);
1315 rc = -EINVAL;
1316 goto out;
1317 }
1318 read_lock(&state->ss->policy_rwlock);
1319 policydb = &state->ss->policydb;
1320 sidtab = &state->ss->sidtab;
1321 if (force)
1322 context = sidtab_search_force(sidtab, sid);
1323 else
1324 context = sidtab_search(sidtab, sid);
1325 if (!context) {
1326 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1327 __func__, sid);
1328 rc = -EINVAL;
1329 goto out_unlock;
1330 }
1331 rc = context_struct_to_string(policydb, context, scontext,
1332 scontext_len);
1333out_unlock:
1334 read_unlock(&state->ss->policy_rwlock);
1335out:
1336 return rc;
1337
1338}
1339
1340/**
1341 * security_sid_to_context - Obtain a context for a given SID.
1342 * @sid: security identifier, SID
1343 * @scontext: security context
1344 * @scontext_len: length in bytes
1345 *
1346 * Write the string representation of the context associated with @sid
1347 * into a dynamically allocated string of the correct size. Set @scontext
1348 * to point to this string and set @scontext_len to the length of the string.
1349 */
1350int security_sid_to_context(struct selinux_state *state,
1351 u32 sid, char **scontext, u32 *scontext_len)
1352{
1353 return security_sid_to_context_core(state, sid, scontext,
1354 scontext_len, 0);
1355}
1356
1357int security_sid_to_context_force(struct selinux_state *state, u32 sid,
1358 char **scontext, u32 *scontext_len)
1359{
1360 return security_sid_to_context_core(state, sid, scontext,
1361 scontext_len, 1);
1362}
1363
1364/*
1365 * Caveat: Mutates scontext.
1366 */
1367static int string_to_context_struct(struct policydb *pol,
1368 struct sidtab *sidtabp,
1369 char *scontext,
1370 u32 scontext_len,
1371 struct context *ctx,
1372 u32 def_sid)
1373{
1374 struct role_datum *role;
1375 struct type_datum *typdatum;
1376 struct user_datum *usrdatum;
1377 char *scontextp, *p, oldc;
1378 int rc = 0;
1379
1380 context_init(ctx);
1381
1382 /* Parse the security context. */
1383
1384 rc = -EINVAL;
1385 scontextp = (char *) scontext;
1386
1387 /* Extract the user. */
1388 p = scontextp;
1389 while (*p && *p != ':')
1390 p++;
1391
1392 if (*p == 0)
1393 goto out;
1394
1395 *p++ = 0;
1396
1397 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1398 if (!usrdatum)
1399 goto out;
1400
1401 ctx->user = usrdatum->value;
1402
1403 /* Extract role. */
1404 scontextp = p;
1405 while (*p && *p != ':')
1406 p++;
1407
1408 if (*p == 0)
1409 goto out;
1410
1411 *p++ = 0;
1412
1413 role = hashtab_search(pol->p_roles.table, scontextp);
1414 if (!role)
1415 goto out;
1416 ctx->role = role->value;
1417
1418 /* Extract type. */
1419 scontextp = p;
1420 while (*p && *p != ':')
1421 p++;
1422 oldc = *p;
1423 *p++ = 0;
1424
1425 typdatum = hashtab_search(pol->p_types.table, scontextp);
1426 if (!typdatum || typdatum->attribute)
1427 goto out;
1428
1429 ctx->type = typdatum->value;
1430
1431 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1432 if (rc)
1433 goto out;
1434
1435 rc = -EINVAL;
1436 if ((p - scontext) < scontext_len)
1437 goto out;
1438
1439 /* Check the validity of the new context. */
1440 if (!policydb_context_isvalid(pol, ctx))
1441 goto out;
1442 rc = 0;
1443out:
1444 if (rc)
1445 context_destroy(ctx);
1446 return rc;
1447}
1448
1449static int security_context_to_sid_core(struct selinux_state *state,
1450 const char *scontext, u32 scontext_len,
1451 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1452 int force)
1453{
1454 struct policydb *policydb;
1455 struct sidtab *sidtab;
1456 char *scontext2, *str = NULL;
1457 struct context context;
1458 int rc = 0;
1459
1460 /* An empty security context is never valid. */
1461 if (!scontext_len)
1462 return -EINVAL;
1463
1464 /* Copy the string to allow changes and ensure a NUL terminator */
1465 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags);
1466 if (!scontext2)
1467 return -ENOMEM;
1468
1469 if (!state->initialized) {
1470 int i;
1471
1472 for (i = 1; i < SECINITSID_NUM; i++) {
1473 if (!strcmp(initial_sid_to_string[i], scontext2)) {
1474 *sid = i;
1475 goto out;
1476 }
1477 }
1478 *sid = SECINITSID_KERNEL;
1479 goto out;
1480 }
1481 *sid = SECSID_NULL;
1482
1483 if (force) {
1484 /* Save another copy for storing in uninterpreted form */
1485 rc = -ENOMEM;
1486 str = kstrdup(scontext2, gfp_flags);
1487 if (!str)
1488 goto out;
1489 }
1490 read_lock(&state->ss->policy_rwlock);
1491 policydb = &state->ss->policydb;
1492 sidtab = &state->ss->sidtab;
1493 rc = string_to_context_struct(policydb, sidtab, scontext2,
1494 scontext_len, &context, def_sid);
1495 if (rc == -EINVAL && force) {
1496 context.str = str;
1497 context.len = strlen(str) + 1;
1498 str = NULL;
1499 } else if (rc)
1500 goto out_unlock;
1501 rc = sidtab_context_to_sid(sidtab, &context, sid);
1502 context_destroy(&context);
1503out_unlock:
1504 read_unlock(&state->ss->policy_rwlock);
1505out:
1506 kfree(scontext2);
1507 kfree(str);
1508 return rc;
1509}
1510
1511/**
1512 * security_context_to_sid - Obtain a SID for a given security context.
1513 * @scontext: security context
1514 * @scontext_len: length in bytes
1515 * @sid: security identifier, SID
1516 * @gfp: context for the allocation
1517 *
1518 * Obtains a SID associated with the security context that
1519 * has the string representation specified by @scontext.
1520 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1521 * memory is available, or 0 on success.
1522 */
1523int security_context_to_sid(struct selinux_state *state,
1524 const char *scontext, u32 scontext_len, u32 *sid,
1525 gfp_t gfp)
1526{
1527 return security_context_to_sid_core(state, scontext, scontext_len,
1528 sid, SECSID_NULL, gfp, 0);
1529}
1530
1531int security_context_str_to_sid(struct selinux_state *state,
1532 const char *scontext, u32 *sid, gfp_t gfp)
1533{
1534 return security_context_to_sid(state, scontext, strlen(scontext),
1535 sid, gfp);
1536}
1537
1538/**
1539 * security_context_to_sid_default - Obtain a SID for a given security context,
1540 * falling back to specified default if needed.
1541 *
1542 * @scontext: security context
1543 * @scontext_len: length in bytes
1544 * @sid: security identifier, SID
1545 * @def_sid: default SID to assign on error
1546 *
1547 * Obtains a SID associated with the security context that
1548 * has the string representation specified by @scontext.
1549 * The default SID is passed to the MLS layer to be used to allow
1550 * kernel labeling of the MLS field if the MLS field is not present
1551 * (for upgrading to MLS without full relabel).
1552 * Implicitly forces adding of the context even if it cannot be mapped yet.
1553 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1554 * memory is available, or 0 on success.
1555 */
1556int security_context_to_sid_default(struct selinux_state *state,
1557 const char *scontext, u32 scontext_len,
1558 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1559{
1560 return security_context_to_sid_core(state, scontext, scontext_len,
1561 sid, def_sid, gfp_flags, 1);
1562}
1563
1564int security_context_to_sid_force(struct selinux_state *state,
1565 const char *scontext, u32 scontext_len,
1566 u32 *sid)
1567{
1568 return security_context_to_sid_core(state, scontext, scontext_len,
1569 sid, SECSID_NULL, GFP_KERNEL, 1);
1570}
1571
1572static int compute_sid_handle_invalid_context(
1573 struct selinux_state *state,
1574 struct context *scontext,
1575 struct context *tcontext,
1576 u16 tclass,
1577 struct context *newcontext)
1578{
1579 struct policydb *policydb = &state->ss->policydb;
1580 char *s = NULL, *t = NULL, *n = NULL;
1581 u32 slen, tlen, nlen;
1582
1583 if (context_struct_to_string(policydb, scontext, &s, &slen))
1584 goto out;
1585 if (context_struct_to_string(policydb, tcontext, &t, &tlen))
1586 goto out;
1587 if (context_struct_to_string(policydb, newcontext, &n, &nlen))
1588 goto out;
1589 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1590 "op=security_compute_sid invalid_context=%s"
1591 " scontext=%s"
1592 " tcontext=%s"
1593 " tclass=%s",
1594 n, s, t, sym_name(policydb, SYM_CLASSES, tclass-1));
1595out:
1596 kfree(s);
1597 kfree(t);
1598 kfree(n);
1599 if (!enforcing_enabled(state))
1600 return 0;
1601 return -EACCES;
1602}
1603
1604static void filename_compute_type(struct policydb *policydb,
1605 struct context *newcontext,
1606 u32 stype, u32 ttype, u16 tclass,
1607 const char *objname)
1608{
1609 struct filename_trans ft;
1610 struct filename_trans_datum *otype;
1611
1612 /*
1613 * Most filename trans rules are going to live in specific directories
1614 * like /dev or /var/run. This bitmap will quickly skip rule searches
1615 * if the ttype does not contain any rules.
1616 */
1617 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype))
1618 return;
1619
1620 ft.stype = stype;
1621 ft.ttype = ttype;
1622 ft.tclass = tclass;
1623 ft.name = objname;
1624
1625 otype = hashtab_search(policydb->filename_trans, &ft);
1626 if (otype)
1627 newcontext->type = otype->otype;
1628}
1629
1630static int security_compute_sid(struct selinux_state *state,
1631 u32 ssid,
1632 u32 tsid,
1633 u16 orig_tclass,
1634 u32 specified,
1635 const char *objname,
1636 u32 *out_sid,
1637 bool kern)
1638{
1639 struct policydb *policydb;
1640 struct sidtab *sidtab;
1641 struct class_datum *cladatum = NULL;
1642 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1643 struct role_trans *roletr = NULL;
1644 struct avtab_key avkey;
1645 struct avtab_datum *avdatum;
1646 struct avtab_node *node;
1647 u16 tclass;
1648 int rc = 0;
1649 bool sock;
1650
1651 if (!state->initialized) {
1652 switch (orig_tclass) {
1653 case SECCLASS_PROCESS: /* kernel value */
1654 *out_sid = ssid;
1655 break;
1656 default:
1657 *out_sid = tsid;
1658 break;
1659 }
1660 goto out;
1661 }
1662
1663 context_init(&newcontext);
1664
1665 read_lock(&state->ss->policy_rwlock);
1666
1667 if (kern) {
1668 tclass = unmap_class(&state->ss->map, orig_tclass);
1669 sock = security_is_socket_class(orig_tclass);
1670 } else {
1671 tclass = orig_tclass;
1672 sock = security_is_socket_class(map_class(&state->ss->map,
1673 tclass));
1674 }
1675
1676 policydb = &state->ss->policydb;
1677 sidtab = &state->ss->sidtab;
1678
1679 scontext = sidtab_search(sidtab, ssid);
1680 if (!scontext) {
1681 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1682 __func__, ssid);
1683 rc = -EINVAL;
1684 goto out_unlock;
1685 }
1686 tcontext = sidtab_search(sidtab, tsid);
1687 if (!tcontext) {
1688 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1689 __func__, tsid);
1690 rc = -EINVAL;
1691 goto out_unlock;
1692 }
1693
1694 if (tclass && tclass <= policydb->p_classes.nprim)
1695 cladatum = policydb->class_val_to_struct[tclass - 1];
1696
1697 /* Set the user identity. */
1698 switch (specified) {
1699 case AVTAB_TRANSITION:
1700 case AVTAB_CHANGE:
1701 if (cladatum && cladatum->default_user == DEFAULT_TARGET) {
1702 newcontext.user = tcontext->user;
1703 } else {
1704 /* notice this gets both DEFAULT_SOURCE and unset */
1705 /* Use the process user identity. */
1706 newcontext.user = scontext->user;
1707 }
1708 break;
1709 case AVTAB_MEMBER:
1710 /* Use the related object owner. */
1711 newcontext.user = tcontext->user;
1712 break;
1713 }
1714
1715 /* Set the role to default values. */
1716 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) {
1717 newcontext.role = scontext->role;
1718 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) {
1719 newcontext.role = tcontext->role;
1720 } else {
1721 if ((tclass == policydb->process_class) || (sock == true))
1722 newcontext.role = scontext->role;
1723 else
1724 newcontext.role = OBJECT_R_VAL;
1725 }
1726
1727 /* Set the type to default values. */
1728 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) {
1729 newcontext.type = scontext->type;
1730 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) {
1731 newcontext.type = tcontext->type;
1732 } else {
1733 if ((tclass == policydb->process_class) || (sock == true)) {
1734 /* Use the type of process. */
1735 newcontext.type = scontext->type;
1736 } else {
1737 /* Use the type of the related object. */
1738 newcontext.type = tcontext->type;
1739 }
1740 }
1741
1742 /* Look for a type transition/member/change rule. */
1743 avkey.source_type = scontext->type;
1744 avkey.target_type = tcontext->type;
1745 avkey.target_class = tclass;
1746 avkey.specified = specified;
1747 avdatum = avtab_search(&policydb->te_avtab, &avkey);
1748
1749 /* If no permanent rule, also check for enabled conditional rules */
1750 if (!avdatum) {
1751 node = avtab_search_node(&policydb->te_cond_avtab, &avkey);
1752 for (; node; node = avtab_search_node_next(node, specified)) {
1753 if (node->key.specified & AVTAB_ENABLED) {
1754 avdatum = &node->datum;
1755 break;
1756 }
1757 }
1758 }
1759
1760 if (avdatum) {
1761 /* Use the type from the type transition/member/change rule. */
1762 newcontext.type = avdatum->u.data;
1763 }
1764
1765 /* if we have a objname this is a file trans check so check those rules */
1766 if (objname)
1767 filename_compute_type(policydb, &newcontext, scontext->type,
1768 tcontext->type, tclass, objname);
1769
1770 /* Check for class-specific changes. */
1771 if (specified & AVTAB_TRANSITION) {
1772 /* Look for a role transition rule. */
1773 for (roletr = policydb->role_tr; roletr;
1774 roletr = roletr->next) {
1775 if ((roletr->role == scontext->role) &&
1776 (roletr->type == tcontext->type) &&
1777 (roletr->tclass == tclass)) {
1778 /* Use the role transition rule. */
1779 newcontext.role = roletr->new_role;
1780 break;
1781 }
1782 }
1783 }
1784
1785 /* Set the MLS attributes.
1786 This is done last because it may allocate memory. */
1787 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified,
1788 &newcontext, sock);
1789 if (rc)
1790 goto out_unlock;
1791
1792 /* Check the validity of the context. */
1793 if (!policydb_context_isvalid(policydb, &newcontext)) {
1794 rc = compute_sid_handle_invalid_context(state, scontext,
1795 tcontext,
1796 tclass,
1797 &newcontext);
1798 if (rc)
1799 goto out_unlock;
1800 }
1801 /* Obtain the sid for the context. */
1802 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
1803out_unlock:
1804 read_unlock(&state->ss->policy_rwlock);
1805 context_destroy(&newcontext);
1806out:
1807 return rc;
1808}
1809
1810/**
1811 * security_transition_sid - Compute the SID for a new subject/object.
1812 * @ssid: source security identifier
1813 * @tsid: target security identifier
1814 * @tclass: target security class
1815 * @out_sid: security identifier for new subject/object
1816 *
1817 * Compute a SID to use for labeling a new subject or object in the
1818 * class @tclass based on a SID pair (@ssid, @tsid).
1819 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1820 * if insufficient memory is available, or %0 if the new SID was
1821 * computed successfully.
1822 */
1823int security_transition_sid(struct selinux_state *state,
1824 u32 ssid, u32 tsid, u16 tclass,
1825 const struct qstr *qstr, u32 *out_sid)
1826{
1827 return security_compute_sid(state, ssid, tsid, tclass,
1828 AVTAB_TRANSITION,
1829 qstr ? qstr->name : NULL, out_sid, true);
1830}
1831
1832int security_transition_sid_user(struct selinux_state *state,
1833 u32 ssid, u32 tsid, u16 tclass,
1834 const char *objname, u32 *out_sid)
1835{
1836 return security_compute_sid(state, ssid, tsid, tclass,
1837 AVTAB_TRANSITION,
1838 objname, out_sid, false);
1839}
1840
1841/**
1842 * security_member_sid - Compute the SID for member selection.
1843 * @ssid: source security identifier
1844 * @tsid: target security identifier
1845 * @tclass: target security class
1846 * @out_sid: security identifier for selected member
1847 *
1848 * Compute a SID to use when selecting a member of a polyinstantiated
1849 * object of class @tclass based on a SID pair (@ssid, @tsid).
1850 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1851 * if insufficient memory is available, or %0 if the SID was
1852 * computed successfully.
1853 */
1854int security_member_sid(struct selinux_state *state,
1855 u32 ssid,
1856 u32 tsid,
1857 u16 tclass,
1858 u32 *out_sid)
1859{
1860 return security_compute_sid(state, ssid, tsid, tclass,
1861 AVTAB_MEMBER, NULL,
1862 out_sid, false);
1863}
1864
1865/**
1866 * security_change_sid - Compute the SID for object relabeling.
1867 * @ssid: source security identifier
1868 * @tsid: target security identifier
1869 * @tclass: target security class
1870 * @out_sid: security identifier for selected member
1871 *
1872 * Compute a SID to use for relabeling an object of class @tclass
1873 * based on a SID pair (@ssid, @tsid).
1874 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1875 * if insufficient memory is available, or %0 if the SID was
1876 * computed successfully.
1877 */
1878int security_change_sid(struct selinux_state *state,
1879 u32 ssid,
1880 u32 tsid,
1881 u16 tclass,
1882 u32 *out_sid)
1883{
1884 return security_compute_sid(state,
1885 ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1886 out_sid, false);
1887}
1888
1889/* Clone the SID into the new SID table. */
1890static int clone_sid(u32 sid,
1891 struct context *context,
1892 void *arg)
1893{
1894 struct sidtab *s = arg;
1895
1896 if (sid > SECINITSID_NUM)
1897 return sidtab_insert(s, sid, context);
1898 else
1899 return 0;
1900}
1901
1902static inline int convert_context_handle_invalid_context(
1903 struct selinux_state *state,
1904 struct context *context)
1905{
1906 struct policydb *policydb = &state->ss->policydb;
1907 char *s;
1908 u32 len;
1909
1910 if (enforcing_enabled(state))
1911 return -EINVAL;
1912
1913 if (!context_struct_to_string(policydb, context, &s, &len)) {
1914 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s);
1915 kfree(s);
1916 }
1917 return 0;
1918}
1919
1920struct convert_context_args {
1921 struct selinux_state *state;
1922 struct policydb *oldp;
1923 struct policydb *newp;
1924};
1925
1926/*
1927 * Convert the values in the security context
1928 * structure `c' from the values specified
1929 * in the policy `p->oldp' to the values specified
1930 * in the policy `p->newp'. Verify that the
1931 * context is valid under the new policy.
1932 */
1933static int convert_context(u32 key,
1934 struct context *c,
1935 void *p)
1936{
1937 struct convert_context_args *args;
1938 struct context oldc;
1939 struct ocontext *oc;
1940 struct mls_range *range;
1941 struct role_datum *role;
1942 struct type_datum *typdatum;
1943 struct user_datum *usrdatum;
1944 char *s;
1945 u32 len;
1946 int rc = 0;
1947
1948 if (key <= SECINITSID_NUM)
1949 goto out;
1950
1951 args = p;
1952
1953 if (c->str) {
1954 struct context ctx;
1955
1956 rc = -ENOMEM;
1957 s = kstrdup(c->str, GFP_KERNEL);
1958 if (!s)
1959 goto out;
1960
1961 rc = string_to_context_struct(args->newp, NULL, s,
1962 c->len, &ctx, SECSID_NULL);
1963 kfree(s);
1964 if (!rc) {
1965 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n",
1966 c->str);
1967 /* Replace string with mapped representation. */
1968 kfree(c->str);
1969 memcpy(c, &ctx, sizeof(*c));
1970 goto out;
1971 } else if (rc == -EINVAL) {
1972 /* Retain string representation for later mapping. */
1973 rc = 0;
1974 goto out;
1975 } else {
1976 /* Other error condition, e.g. ENOMEM. */
1977 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n",
1978 c->str, -rc);
1979 goto out;
1980 }
1981 }
1982
1983 rc = context_cpy(&oldc, c);
1984 if (rc)
1985 goto out;
1986
1987 /* Convert the user. */
1988 rc = -EINVAL;
1989 usrdatum = hashtab_search(args->newp->p_users.table,
1990 sym_name(args->oldp, SYM_USERS, c->user - 1));
1991 if (!usrdatum)
1992 goto bad;
1993 c->user = usrdatum->value;
1994
1995 /* Convert the role. */
1996 rc = -EINVAL;
1997 role = hashtab_search(args->newp->p_roles.table,
1998 sym_name(args->oldp, SYM_ROLES, c->role - 1));
1999 if (!role)
2000 goto bad;
2001 c->role = role->value;
2002
2003 /* Convert the type. */
2004 rc = -EINVAL;
2005 typdatum = hashtab_search(args->newp->p_types.table,
2006 sym_name(args->oldp, SYM_TYPES, c->type - 1));
2007 if (!typdatum)
2008 goto bad;
2009 c->type = typdatum->value;
2010
2011 /* Convert the MLS fields if dealing with MLS policies */
2012 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
2013 rc = mls_convert_context(args->oldp, args->newp, c);
2014 if (rc)
2015 goto bad;
2016 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
2017 /*
2018 * Switching between MLS and non-MLS policy:
2019 * free any storage used by the MLS fields in the
2020 * context for all existing entries in the sidtab.
2021 */
2022 mls_context_destroy(c);
2023 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
2024 /*
2025 * Switching between non-MLS and MLS policy:
2026 * ensure that the MLS fields of the context for all
2027 * existing entries in the sidtab are filled in with a
2028 * suitable default value, likely taken from one of the
2029 * initial SIDs.
2030 */
2031 oc = args->newp->ocontexts[OCON_ISID];
2032 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
2033 oc = oc->next;
2034 rc = -EINVAL;
2035 if (!oc) {
2036 printk(KERN_ERR "SELinux: unable to look up"
2037 " the initial SIDs list\n");
2038 goto bad;
2039 }
2040 range = &oc->context[0].range;
2041 rc = mls_range_set(c, range);
2042 if (rc)
2043 goto bad;
2044 }
2045
2046 /* Check the validity of the new context. */
2047 if (!policydb_context_isvalid(args->newp, c)) {
2048 rc = convert_context_handle_invalid_context(args->state,
2049 &oldc);
2050 if (rc)
2051 goto bad;
2052 }
2053
2054 context_destroy(&oldc);
2055
2056 rc = 0;
2057out:
2058 return rc;
2059bad:
2060 /* Map old representation to string and save it. */
2061 rc = context_struct_to_string(args->oldp, &oldc, &s, &len);
2062 if (rc)
2063 return rc;
2064 context_destroy(&oldc);
2065 context_destroy(c);
2066 c->str = s;
2067 c->len = len;
2068 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n",
2069 c->str);
2070 rc = 0;
2071 goto out;
2072}
2073
2074static void security_load_policycaps(struct selinux_state *state)
2075{
2076 struct policydb *p = &state->ss->policydb;
2077 unsigned int i;
2078 struct ebitmap_node *node;
2079
2080 for (i = 0; i < ARRAY_SIZE(state->policycap); i++)
2081 state->policycap[i] = ebitmap_get_bit(&p->policycaps, i);
2082
2083 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
2084 pr_info("SELinux: policy capability %s=%d\n",
2085 selinux_policycap_names[i],
2086 ebitmap_get_bit(&p->policycaps, i));
2087
2088 ebitmap_for_each_positive_bit(&p->policycaps, node, i) {
2089 if (i >= ARRAY_SIZE(selinux_policycap_names))
2090 pr_info("SELinux: unknown policy capability %u\n",
2091 i);
2092 }
2093}
2094
2095static int security_preserve_bools(struct selinux_state *state,
2096 struct policydb *newpolicydb);
2097
2098/**
2099 * security_load_policy - Load a security policy configuration.
2100 * @data: binary policy data
2101 * @len: length of data in bytes
2102 *
2103 * Load a new set of security policy configuration data,
2104 * validate it and convert the SID table as necessary.
2105 * This function will flush the access vector cache after
2106 * loading the new policy.
2107 */
2108int security_load_policy(struct selinux_state *state, void *data, size_t len)
2109{
2110 struct policydb *policydb;
2111 struct sidtab *sidtab;
2112 struct policydb *oldpolicydb, *newpolicydb;
2113 struct sidtab oldsidtab, newsidtab;
2114 struct selinux_mapping *oldmapping;
2115 struct selinux_map newmap;
2116 struct convert_context_args args;
2117 u32 seqno;
2118 int rc = 0;
2119 struct policy_file file = { data, len }, *fp = &file;
2120
2121 oldpolicydb = kzalloc(2 * sizeof(*oldpolicydb), GFP_KERNEL);
2122 if (!oldpolicydb) {
2123 rc = -ENOMEM;
2124 goto out;
2125 }
2126 newpolicydb = oldpolicydb + 1;
2127
2128 policydb = &state->ss->policydb;
2129 sidtab = &state->ss->sidtab;
2130
2131 if (!state->initialized) {
2132 rc = policydb_read(policydb, fp);
2133 if (rc)
2134 goto out;
2135
2136 policydb->len = len;
2137 rc = selinux_set_mapping(policydb, secclass_map,
2138 &state->ss->map);
2139 if (rc) {
2140 policydb_destroy(policydb);
2141 goto out;
2142 }
2143
2144 rc = policydb_load_isids(policydb, sidtab);
2145 if (rc) {
2146 policydb_destroy(policydb);
2147 goto out;
2148 }
2149
2150 security_load_policycaps(state);
2151 state->initialized = 1;
2152 seqno = ++state->ss->latest_granting;
2153 selinux_complete_init();
2154 avc_ss_reset(state->avc, seqno);
2155 selnl_notify_policyload(seqno);
2156 selinux_status_update_policyload(state, seqno);
2157 selinux_netlbl_cache_invalidate();
2158 selinux_xfrm_notify_policyload();
2159 goto out;
2160 }
2161
2162#if 0
2163 sidtab_hash_eval(sidtab, "sids");
2164#endif
2165
2166 rc = policydb_read(newpolicydb, fp);
2167 if (rc)
2168 goto out;
2169
2170 newpolicydb->len = len;
2171 /* If switching between different policy types, log MLS status */
2172 if (policydb->mls_enabled && !newpolicydb->mls_enabled)
2173 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
2174 else if (!policydb->mls_enabled && newpolicydb->mls_enabled)
2175 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
2176
2177 rc = policydb_load_isids(newpolicydb, &newsidtab);
2178 if (rc) {
2179 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
2180 policydb_destroy(newpolicydb);
2181 goto out;
2182 }
2183
2184 rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap);
2185 if (rc)
2186 goto err;
2187
2188 rc = security_preserve_bools(state, newpolicydb);
2189 if (rc) {
2190 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
2191 goto err;
2192 }
2193
2194 /* Clone the SID table. */
2195 sidtab_shutdown(sidtab);
2196
2197 rc = sidtab_map(sidtab, clone_sid, &newsidtab);
2198 if (rc)
2199 goto err;
2200
2201 /*
2202 * Convert the internal representations of contexts
2203 * in the new SID table.
2204 */
2205 args.state = state;
2206 args.oldp = policydb;
2207 args.newp = newpolicydb;
2208 rc = sidtab_map(&newsidtab, convert_context, &args);
2209 if (rc) {
2210 printk(KERN_ERR "SELinux: unable to convert the internal"
2211 " representation of contexts in the new SID"
2212 " table\n");
2213 goto err;
2214 }
2215
2216 /* Save the old policydb and SID table to free later. */
2217 memcpy(oldpolicydb, policydb, sizeof(*policydb));
2218 sidtab_set(&oldsidtab, sidtab);
2219
2220 /* Install the new policydb and SID table. */
2221 write_lock_irq(&state->ss->policy_rwlock);
2222 memcpy(policydb, newpolicydb, sizeof(*policydb));
2223 sidtab_set(sidtab, &newsidtab);
2224 security_load_policycaps(state);
2225 oldmapping = state->ss->map.mapping;
2226 state->ss->map.mapping = newmap.mapping;
2227 state->ss->map.size = newmap.size;
2228 seqno = ++state->ss->latest_granting;
2229 write_unlock_irq(&state->ss->policy_rwlock);
2230
2231 /* Free the old policydb and SID table. */
2232 policydb_destroy(oldpolicydb);
2233 sidtab_destroy(&oldsidtab);
2234 kfree(oldmapping);
2235
2236 avc_ss_reset(state->avc, seqno);
2237 selnl_notify_policyload(seqno);
2238 selinux_status_update_policyload(state, seqno);
2239 selinux_netlbl_cache_invalidate();
2240 selinux_xfrm_notify_policyload();
2241
2242 rc = 0;
2243 goto out;
2244
2245err:
2246 kfree(newmap.mapping);
2247 sidtab_destroy(&newsidtab);
2248 policydb_destroy(newpolicydb);
2249
2250out:
2251 kfree(oldpolicydb);
2252 return rc;
2253}
2254
2255size_t security_policydb_len(struct selinux_state *state)
2256{
2257 struct policydb *p = &state->ss->policydb;
2258 size_t len;
2259
2260 read_lock(&state->ss->policy_rwlock);
2261 len = p->len;
2262 read_unlock(&state->ss->policy_rwlock);
2263
2264 return len;
2265}
2266
2267/**
2268 * security_port_sid - Obtain the SID for a port.
2269 * @protocol: protocol number
2270 * @port: port number
2271 * @out_sid: security identifier
2272 */
2273int security_port_sid(struct selinux_state *state,
2274 u8 protocol, u16 port, u32 *out_sid)
2275{
2276 struct policydb *policydb;
2277 struct sidtab *sidtab;
2278 struct ocontext *c;
2279 int rc = 0;
2280
2281 read_lock(&state->ss->policy_rwlock);
2282
2283 policydb = &state->ss->policydb;
2284 sidtab = &state->ss->sidtab;
2285
2286 c = policydb->ocontexts[OCON_PORT];
2287 while (c) {
2288 if (c->u.port.protocol == protocol &&
2289 c->u.port.low_port <= port &&
2290 c->u.port.high_port >= port)
2291 break;
2292 c = c->next;
2293 }
2294
2295 if (c) {
2296 if (!c->sid[0]) {
2297 rc = sidtab_context_to_sid(sidtab,
2298 &c->context[0],
2299 &c->sid[0]);
2300 if (rc)
2301 goto out;
2302 }
2303 *out_sid = c->sid[0];
2304 } else {
2305 *out_sid = SECINITSID_PORT;
2306 }
2307
2308out:
2309 read_unlock(&state->ss->policy_rwlock);
2310 return rc;
2311}
2312
2313/**
2314 * security_pkey_sid - Obtain the SID for a pkey.
2315 * @subnet_prefix: Subnet Prefix
2316 * @pkey_num: pkey number
2317 * @out_sid: security identifier
2318 */
2319int security_ib_pkey_sid(struct selinux_state *state,
2320 u64 subnet_prefix, u16 pkey_num, u32 *out_sid)
2321{
2322 struct policydb *policydb;
2323 struct sidtab *sidtab;
2324 struct ocontext *c;
2325 int rc = 0;
2326
2327 read_lock(&state->ss->policy_rwlock);
2328
2329 policydb = &state->ss->policydb;
2330 sidtab = &state->ss->sidtab;
2331
2332 c = policydb->ocontexts[OCON_IBPKEY];
2333 while (c) {
2334 if (c->u.ibpkey.low_pkey <= pkey_num &&
2335 c->u.ibpkey.high_pkey >= pkey_num &&
2336 c->u.ibpkey.subnet_prefix == subnet_prefix)
2337 break;
2338
2339 c = c->next;
2340 }
2341
2342 if (c) {
2343 if (!c->sid[0]) {
2344 rc = sidtab_context_to_sid(sidtab,
2345 &c->context[0],
2346 &c->sid[0]);
2347 if (rc)
2348 goto out;
2349 }
2350 *out_sid = c->sid[0];
2351 } else
2352 *out_sid = SECINITSID_UNLABELED;
2353
2354out:
2355 read_unlock(&state->ss->policy_rwlock);
2356 return rc;
2357}
2358
2359/**
2360 * security_ib_endport_sid - Obtain the SID for a subnet management interface.
2361 * @dev_name: device name
2362 * @port: port number
2363 * @out_sid: security identifier
2364 */
2365int security_ib_endport_sid(struct selinux_state *state,
2366 const char *dev_name, u8 port_num, u32 *out_sid)
2367{
2368 struct policydb *policydb;
2369 struct sidtab *sidtab;
2370 struct ocontext *c;
2371 int rc = 0;
2372
2373 read_lock(&state->ss->policy_rwlock);
2374
2375 policydb = &state->ss->policydb;
2376 sidtab = &state->ss->sidtab;
2377
2378 c = policydb->ocontexts[OCON_IBENDPORT];
2379 while (c) {
2380 if (c->u.ibendport.port == port_num &&
2381 !strncmp(c->u.ibendport.dev_name,
2382 dev_name,
2383 IB_DEVICE_NAME_MAX))
2384 break;
2385
2386 c = c->next;
2387 }
2388
2389 if (c) {
2390 if (!c->sid[0]) {
2391 rc = sidtab_context_to_sid(sidtab,
2392 &c->context[0],
2393 &c->sid[0]);
2394 if (rc)
2395 goto out;
2396 }
2397 *out_sid = c->sid[0];
2398 } else
2399 *out_sid = SECINITSID_UNLABELED;
2400
2401out:
2402 read_unlock(&state->ss->policy_rwlock);
2403 return rc;
2404}
2405
2406/**
2407 * security_netif_sid - Obtain the SID for a network interface.
2408 * @name: interface name
2409 * @if_sid: interface SID
2410 */
2411int security_netif_sid(struct selinux_state *state,
2412 char *name, u32 *if_sid)
2413{
2414 struct policydb *policydb;
2415 struct sidtab *sidtab;
2416 int rc = 0;
2417 struct ocontext *c;
2418
2419 read_lock(&state->ss->policy_rwlock);
2420
2421 policydb = &state->ss->policydb;
2422 sidtab = &state->ss->sidtab;
2423
2424 c = policydb->ocontexts[OCON_NETIF];
2425 while (c) {
2426 if (strcmp(name, c->u.name) == 0)
2427 break;
2428 c = c->next;
2429 }
2430
2431 if (c) {
2432 if (!c->sid[0] || !c->sid[1]) {
2433 rc = sidtab_context_to_sid(sidtab,
2434 &c->context[0],
2435 &c->sid[0]);
2436 if (rc)
2437 goto out;
2438 rc = sidtab_context_to_sid(sidtab,
2439 &c->context[1],
2440 &c->sid[1]);
2441 if (rc)
2442 goto out;
2443 }
2444 *if_sid = c->sid[0];
2445 } else
2446 *if_sid = SECINITSID_NETIF;
2447
2448out:
2449 read_unlock(&state->ss->policy_rwlock);
2450 return rc;
2451}
2452
2453static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2454{
2455 int i, fail = 0;
2456
2457 for (i = 0; i < 4; i++)
2458 if (addr[i] != (input[i] & mask[i])) {
2459 fail = 1;
2460 break;
2461 }
2462
2463 return !fail;
2464}
2465
2466/**
2467 * security_node_sid - Obtain the SID for a node (host).
2468 * @domain: communication domain aka address family
2469 * @addrp: address
2470 * @addrlen: address length in bytes
2471 * @out_sid: security identifier
2472 */
2473int security_node_sid(struct selinux_state *state,
2474 u16 domain,
2475 void *addrp,
2476 u32 addrlen,
2477 u32 *out_sid)
2478{
2479 struct policydb *policydb;
2480 struct sidtab *sidtab;
2481 int rc;
2482 struct ocontext *c;
2483
2484 read_lock(&state->ss->policy_rwlock);
2485
2486 policydb = &state->ss->policydb;
2487 sidtab = &state->ss->sidtab;
2488
2489 switch (domain) {
2490 case AF_INET: {
2491 u32 addr;
2492
2493 rc = -EINVAL;
2494 if (addrlen != sizeof(u32))
2495 goto out;
2496
2497 addr = *((u32 *)addrp);
2498
2499 c = policydb->ocontexts[OCON_NODE];
2500 while (c) {
2501 if (c->u.node.addr == (addr & c->u.node.mask))
2502 break;
2503 c = c->next;
2504 }
2505 break;
2506 }
2507
2508 case AF_INET6:
2509 rc = -EINVAL;
2510 if (addrlen != sizeof(u64) * 2)
2511 goto out;
2512 c = policydb->ocontexts[OCON_NODE6];
2513 while (c) {
2514 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2515 c->u.node6.mask))
2516 break;
2517 c = c->next;
2518 }
2519 break;
2520
2521 default:
2522 rc = 0;
2523 *out_sid = SECINITSID_NODE;
2524 goto out;
2525 }
2526
2527 if (c) {
2528 if (!c->sid[0]) {
2529 rc = sidtab_context_to_sid(sidtab,
2530 &c->context[0],
2531 &c->sid[0]);
2532 if (rc)
2533 goto out;
2534 }
2535 *out_sid = c->sid[0];
2536 } else {
2537 *out_sid = SECINITSID_NODE;
2538 }
2539
2540 rc = 0;
2541out:
2542 read_unlock(&state->ss->policy_rwlock);
2543 return rc;
2544}
2545
2546#define SIDS_NEL 25
2547
2548/**
2549 * security_get_user_sids - Obtain reachable SIDs for a user.
2550 * @fromsid: starting SID
2551 * @username: username
2552 * @sids: array of reachable SIDs for user
2553 * @nel: number of elements in @sids
2554 *
2555 * Generate the set of SIDs for legal security contexts
2556 * for a given user that can be reached by @fromsid.
2557 * Set *@sids to point to a dynamically allocated
2558 * array containing the set of SIDs. Set *@nel to the
2559 * number of elements in the array.
2560 */
2561
2562int security_get_user_sids(struct selinux_state *state,
2563 u32 fromsid,
2564 char *username,
2565 u32 **sids,
2566 u32 *nel)
2567{
2568 struct policydb *policydb;
2569 struct sidtab *sidtab;
2570 struct context *fromcon, usercon;
2571 u32 *mysids = NULL, *mysids2, sid;
2572 u32 mynel = 0, maxnel = SIDS_NEL;
2573 struct user_datum *user;
2574 struct role_datum *role;
2575 struct ebitmap_node *rnode, *tnode;
2576 int rc = 0, i, j;
2577
2578 *sids = NULL;
2579 *nel = 0;
2580
2581 if (!state->initialized)
2582 goto out;
2583
2584 read_lock(&state->ss->policy_rwlock);
2585
2586 policydb = &state->ss->policydb;
2587 sidtab = &state->ss->sidtab;
2588
2589 context_init(&usercon);
2590
2591 rc = -EINVAL;
2592 fromcon = sidtab_search(sidtab, fromsid);
2593 if (!fromcon)
2594 goto out_unlock;
2595
2596 rc = -EINVAL;
2597 user = hashtab_search(policydb->p_users.table, username);
2598 if (!user)
2599 goto out_unlock;
2600
2601 usercon.user = user->value;
2602
2603 rc = -ENOMEM;
2604 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2605 if (!mysids)
2606 goto out_unlock;
2607
2608 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2609 role = policydb->role_val_to_struct[i];
2610 usercon.role = i + 1;
2611 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2612 usercon.type = j + 1;
2613
2614 if (mls_setup_user_range(policydb, fromcon, user,
2615 &usercon))
2616 continue;
2617
2618 rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
2619 if (rc)
2620 goto out_unlock;
2621 if (mynel < maxnel) {
2622 mysids[mynel++] = sid;
2623 } else {
2624 rc = -ENOMEM;
2625 maxnel += SIDS_NEL;
2626 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2627 if (!mysids2)
2628 goto out_unlock;
2629 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2630 kfree(mysids);
2631 mysids = mysids2;
2632 mysids[mynel++] = sid;
2633 }
2634 }
2635 }
2636 rc = 0;
2637out_unlock:
2638 read_unlock(&state->ss->policy_rwlock);
2639 if (rc || !mynel) {
2640 kfree(mysids);
2641 goto out;
2642 }
2643
2644 rc = -ENOMEM;
2645 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2646 if (!mysids2) {
2647 kfree(mysids);
2648 goto out;
2649 }
2650 for (i = 0, j = 0; i < mynel; i++) {
2651 struct av_decision dummy_avd;
2652 rc = avc_has_perm_noaudit(state,
2653 fromsid, mysids[i],
2654 SECCLASS_PROCESS, /* kernel value */
2655 PROCESS__TRANSITION, AVC_STRICT,
2656 &dummy_avd);
2657 if (!rc)
2658 mysids2[j++] = mysids[i];
2659 cond_resched();
2660 }
2661 rc = 0;
2662 kfree(mysids);
2663 *sids = mysids2;
2664 *nel = j;
2665out:
2666 return rc;
2667}
2668
2669/**
2670 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem
2671 * @fstype: filesystem type
2672 * @path: path from root of mount
2673 * @sclass: file security class
2674 * @sid: SID for path
2675 *
2676 * Obtain a SID to use for a file in a filesystem that
2677 * cannot support xattr or use a fixed labeling behavior like
2678 * transition SIDs or task SIDs.
2679 *
2680 * The caller must acquire the policy_rwlock before calling this function.
2681 */
2682static inline int __security_genfs_sid(struct selinux_state *state,
2683 const char *fstype,
2684 char *path,
2685 u16 orig_sclass,
2686 u32 *sid)
2687{
2688 struct policydb *policydb = &state->ss->policydb;
2689 struct sidtab *sidtab = &state->ss->sidtab;
2690 int len;
2691 u16 sclass;
2692 struct genfs *genfs;
2693 struct ocontext *c;
2694 int rc, cmp = 0;
2695
2696 while (path[0] == '/' && path[1] == '/')
2697 path++;
2698
2699 sclass = unmap_class(&state->ss->map, orig_sclass);
2700 *sid = SECINITSID_UNLABELED;
2701
2702 for (genfs = policydb->genfs; genfs; genfs = genfs->next) {
2703 cmp = strcmp(fstype, genfs->fstype);
2704 if (cmp <= 0)
2705 break;
2706 }
2707
2708 rc = -ENOENT;
2709 if (!genfs || cmp)
2710 goto out;
2711
2712 for (c = genfs->head; c; c = c->next) {
2713 len = strlen(c->u.name);
2714 if ((!c->v.sclass || sclass == c->v.sclass) &&
2715 (strncmp(c->u.name, path, len) == 0))
2716 break;
2717 }
2718
2719 rc = -ENOENT;
2720 if (!c)
2721 goto out;
2722
2723 if (!c->sid[0]) {
2724 rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]);
2725 if (rc)
2726 goto out;
2727 }
2728
2729 *sid = c->sid[0];
2730 rc = 0;
2731out:
2732 return rc;
2733}
2734
2735/**
2736 * security_genfs_sid - Obtain a SID for a file in a filesystem
2737 * @fstype: filesystem type
2738 * @path: path from root of mount
2739 * @sclass: file security class
2740 * @sid: SID for path
2741 *
2742 * Acquire policy_rwlock before calling __security_genfs_sid() and release
2743 * it afterward.
2744 */
2745int security_genfs_sid(struct selinux_state *state,
2746 const char *fstype,
2747 char *path,
2748 u16 orig_sclass,
2749 u32 *sid)
2750{
2751 int retval;
2752
2753 read_lock(&state->ss->policy_rwlock);
2754 retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid);
2755 read_unlock(&state->ss->policy_rwlock);
2756 return retval;
2757}
2758
2759/**
2760 * security_fs_use - Determine how to handle labeling for a filesystem.
2761 * @sb: superblock in question
2762 */
2763int security_fs_use(struct selinux_state *state, struct super_block *sb)
2764{
2765 struct policydb *policydb;
2766 struct sidtab *sidtab;
2767 int rc = 0;
2768 struct ocontext *c;
2769 struct superblock_security_struct *sbsec = sb->s_security;
2770 const char *fstype = sb->s_type->name;
2771
2772 read_lock(&state->ss->policy_rwlock);
2773
2774 policydb = &state->ss->policydb;
2775 sidtab = &state->ss->sidtab;
2776
2777 c = policydb->ocontexts[OCON_FSUSE];
2778 while (c) {
2779 if (strcmp(fstype, c->u.name) == 0)
2780 break;
2781 c = c->next;
2782 }
2783
2784 if (c) {
2785 sbsec->behavior = c->v.behavior;
2786 if (!c->sid[0]) {
2787 rc = sidtab_context_to_sid(sidtab, &c->context[0],
2788 &c->sid[0]);
2789 if (rc)
2790 goto out;
2791 }
2792 sbsec->sid = c->sid[0];
2793 } else {
2794 rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR,
2795 &sbsec->sid);
2796 if (rc) {
2797 sbsec->behavior = SECURITY_FS_USE_NONE;
2798 rc = 0;
2799 } else {
2800 sbsec->behavior = SECURITY_FS_USE_GENFS;
2801 }
2802 }
2803
2804out:
2805 read_unlock(&state->ss->policy_rwlock);
2806 return rc;
2807}
2808
2809int security_get_bools(struct selinux_state *state,
2810 int *len, char ***names, int **values)
2811{
2812 struct policydb *policydb;
2813 int i, rc;
2814
2815 if (!state->initialized) {
2816 *len = 0;
2817 *names = NULL;
2818 *values = NULL;
2819 return 0;
2820 }
2821
2822 read_lock(&state->ss->policy_rwlock);
2823
2824 policydb = &state->ss->policydb;
2825
2826 *names = NULL;
2827 *values = NULL;
2828
2829 rc = 0;
2830 *len = policydb->p_bools.nprim;
2831 if (!*len)
2832 goto out;
2833
2834 rc = -ENOMEM;
2835 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2836 if (!*names)
2837 goto err;
2838
2839 rc = -ENOMEM;
2840 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2841 if (!*values)
2842 goto err;
2843
2844 for (i = 0; i < *len; i++) {
2845 (*values)[i] = policydb->bool_val_to_struct[i]->state;
2846
2847 rc = -ENOMEM;
2848 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i),
2849 GFP_ATOMIC);
2850 if (!(*names)[i])
2851 goto err;
2852 }
2853 rc = 0;
2854out:
2855 read_unlock(&state->ss->policy_rwlock);
2856 return rc;
2857err:
2858 if (*names) {
2859 for (i = 0; i < *len; i++)
2860 kfree((*names)[i]);
2861 }
2862 kfree(*values);
2863 goto out;
2864}
2865
2866
2867int security_set_bools(struct selinux_state *state, int len, int *values)
2868{
2869 struct policydb *policydb;
2870 int i, rc;
2871 int lenp, seqno = 0;
2872 struct cond_node *cur;
2873
2874 write_lock_irq(&state->ss->policy_rwlock);
2875
2876 policydb = &state->ss->policydb;
2877
2878 rc = -EFAULT;
2879 lenp = policydb->p_bools.nprim;
2880 if (len != lenp)
2881 goto out;
2882
2883 for (i = 0; i < len; i++) {
2884 if (!!values[i] != policydb->bool_val_to_struct[i]->state) {
2885 audit_log(current->audit_context, GFP_ATOMIC,
2886 AUDIT_MAC_CONFIG_CHANGE,
2887 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2888 sym_name(policydb, SYM_BOOLS, i),
2889 !!values[i],
2890 policydb->bool_val_to_struct[i]->state,
2891 from_kuid(&init_user_ns, audit_get_loginuid(current)),
2892 audit_get_sessionid(current));
2893 }
2894 if (values[i])
2895 policydb->bool_val_to_struct[i]->state = 1;
2896 else
2897 policydb->bool_val_to_struct[i]->state = 0;
2898 }
2899
2900 for (cur = policydb->cond_list; cur; cur = cur->next) {
2901 rc = evaluate_cond_node(policydb, cur);
2902 if (rc)
2903 goto out;
2904 }
2905
2906 seqno = ++state->ss->latest_granting;
2907 rc = 0;
2908out:
2909 write_unlock_irq(&state->ss->policy_rwlock);
2910 if (!rc) {
2911 avc_ss_reset(state->avc, seqno);
2912 selnl_notify_policyload(seqno);
2913 selinux_status_update_policyload(state, seqno);
2914 selinux_xfrm_notify_policyload();
2915 }
2916 return rc;
2917}
2918
2919int security_get_bool_value(struct selinux_state *state,
2920 int index)
2921{
2922 struct policydb *policydb;
2923 int rc;
2924 int len;
2925
2926 read_lock(&state->ss->policy_rwlock);
2927
2928 policydb = &state->ss->policydb;
2929
2930 rc = -EFAULT;
2931 len = policydb->p_bools.nprim;
2932 if (index >= len)
2933 goto out;
2934
2935 rc = policydb->bool_val_to_struct[index]->state;
2936out:
2937 read_unlock(&state->ss->policy_rwlock);
2938 return rc;
2939}
2940
2941static int security_preserve_bools(struct selinux_state *state,
2942 struct policydb *policydb)
2943{
2944 int rc, nbools = 0, *bvalues = NULL, i;
2945 char **bnames = NULL;
2946 struct cond_bool_datum *booldatum;
2947 struct cond_node *cur;
2948
2949 rc = security_get_bools(state, &nbools, &bnames, &bvalues);
2950 if (rc)
2951 goto out;
2952 for (i = 0; i < nbools; i++) {
2953 booldatum = hashtab_search(policydb->p_bools.table, bnames[i]);
2954 if (booldatum)
2955 booldatum->state = bvalues[i];
2956 }
2957 for (cur = policydb->cond_list; cur; cur = cur->next) {
2958 rc = evaluate_cond_node(policydb, cur);
2959 if (rc)
2960 goto out;
2961 }
2962
2963out:
2964 if (bnames) {
2965 for (i = 0; i < nbools; i++)
2966 kfree(bnames[i]);
2967 }
2968 kfree(bnames);
2969 kfree(bvalues);
2970 return rc;
2971}
2972
2973/*
2974 * security_sid_mls_copy() - computes a new sid based on the given
2975 * sid and the mls portion of mls_sid.
2976 */
2977int security_sid_mls_copy(struct selinux_state *state,
2978 u32 sid, u32 mls_sid, u32 *new_sid)
2979{
2980 struct policydb *policydb = &state->ss->policydb;
2981 struct sidtab *sidtab = &state->ss->sidtab;
2982 struct context *context1;
2983 struct context *context2;
2984 struct context newcon;
2985 char *s;
2986 u32 len;
2987 int rc;
2988
2989 rc = 0;
2990 if (!state->initialized || !policydb->mls_enabled) {
2991 *new_sid = sid;
2992 goto out;
2993 }
2994
2995 context_init(&newcon);
2996
2997 read_lock(&state->ss->policy_rwlock);
2998
2999 rc = -EINVAL;
3000 context1 = sidtab_search(sidtab, sid);
3001 if (!context1) {
3002 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
3003 __func__, sid);
3004 goto out_unlock;
3005 }
3006
3007 rc = -EINVAL;
3008 context2 = sidtab_search(sidtab, mls_sid);
3009 if (!context2) {
3010 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
3011 __func__, mls_sid);
3012 goto out_unlock;
3013 }
3014
3015 newcon.user = context1->user;
3016 newcon.role = context1->role;
3017 newcon.type = context1->type;
3018 rc = mls_context_cpy(&newcon, context2);
3019 if (rc)
3020 goto out_unlock;
3021
3022 /* Check the validity of the new context. */
3023 if (!policydb_context_isvalid(policydb, &newcon)) {
3024 rc = convert_context_handle_invalid_context(state, &newcon);
3025 if (rc) {
3026 if (!context_struct_to_string(policydb, &newcon, &s,
3027 &len)) {
3028 audit_log(current->audit_context,
3029 GFP_ATOMIC, AUDIT_SELINUX_ERR,
3030 "op=security_sid_mls_copy "
3031 "invalid_context=%s", s);
3032 kfree(s);
3033 }
3034 goto out_unlock;
3035 }
3036 }
3037
3038 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
3039out_unlock:
3040 read_unlock(&state->ss->policy_rwlock);
3041 context_destroy(&newcon);
3042out:
3043 return rc;
3044}
3045
3046/**
3047 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
3048 * @nlbl_sid: NetLabel SID
3049 * @nlbl_type: NetLabel labeling protocol type
3050 * @xfrm_sid: XFRM SID
3051 *
3052 * Description:
3053 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
3054 * resolved into a single SID it is returned via @peer_sid and the function
3055 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
3056 * returns a negative value. A table summarizing the behavior is below:
3057 *
3058 * | function return | @sid
3059 * ------------------------------+-----------------+-----------------
3060 * no peer labels | 0 | SECSID_NULL
3061 * single peer label | 0 | <peer_label>
3062 * multiple, consistent labels | 0 | <peer_label>
3063 * multiple, inconsistent labels | -<errno> | SECSID_NULL
3064 *
3065 */
3066int security_net_peersid_resolve(struct selinux_state *state,
3067 u32 nlbl_sid, u32 nlbl_type,
3068 u32 xfrm_sid,
3069 u32 *peer_sid)
3070{
3071 struct policydb *policydb = &state->ss->policydb;
3072 struct sidtab *sidtab = &state->ss->sidtab;
3073 int rc;
3074 struct context *nlbl_ctx;
3075 struct context *xfrm_ctx;
3076
3077 *peer_sid = SECSID_NULL;
3078
3079 /* handle the common (which also happens to be the set of easy) cases
3080 * right away, these two if statements catch everything involving a
3081 * single or absent peer SID/label */
3082 if (xfrm_sid == SECSID_NULL) {
3083 *peer_sid = nlbl_sid;
3084 return 0;
3085 }
3086 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
3087 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
3088 * is present */
3089 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
3090 *peer_sid = xfrm_sid;
3091 return 0;
3092 }
3093
3094 /*
3095 * We don't need to check initialized here since the only way both
3096 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
3097 * security server was initialized and state->initialized was true.
3098 */
3099 if (!policydb->mls_enabled)
3100 return 0;
3101
3102 read_lock(&state->ss->policy_rwlock);
3103
3104 rc = -EINVAL;
3105 nlbl_ctx = sidtab_search(sidtab, nlbl_sid);
3106 if (!nlbl_ctx) {
3107 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
3108 __func__, nlbl_sid);
3109 goto out;
3110 }
3111 rc = -EINVAL;
3112 xfrm_ctx = sidtab_search(sidtab, xfrm_sid);
3113 if (!xfrm_ctx) {
3114 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
3115 __func__, xfrm_sid);
3116 goto out;
3117 }
3118 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
3119 if (rc)
3120 goto out;
3121
3122 /* at present NetLabel SIDs/labels really only carry MLS
3123 * information so if the MLS portion of the NetLabel SID
3124 * matches the MLS portion of the labeled XFRM SID/label
3125 * then pass along the XFRM SID as it is the most
3126 * expressive */
3127 *peer_sid = xfrm_sid;
3128out:
3129 read_unlock(&state->ss->policy_rwlock);
3130 return rc;
3131}
3132
3133static int get_classes_callback(void *k, void *d, void *args)
3134{
3135 struct class_datum *datum = d;
3136 char *name = k, **classes = args;
3137 int value = datum->value - 1;
3138
3139 classes[value] = kstrdup(name, GFP_ATOMIC);
3140 if (!classes[value])
3141 return -ENOMEM;
3142
3143 return 0;
3144}
3145
3146int security_get_classes(struct selinux_state *state,
3147 char ***classes, int *nclasses)
3148{
3149 struct policydb *policydb = &state->ss->policydb;
3150 int rc;
3151
3152 if (!state->initialized) {
3153 *nclasses = 0;
3154 *classes = NULL;
3155 return 0;
3156 }
3157
3158 read_lock(&state->ss->policy_rwlock);
3159
3160 rc = -ENOMEM;
3161 *nclasses = policydb->p_classes.nprim;
3162 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
3163 if (!*classes)
3164 goto out;
3165
3166 rc = hashtab_map(policydb->p_classes.table, get_classes_callback,
3167 *classes);
3168 if (rc) {
3169 int i;
3170 for (i = 0; i < *nclasses; i++)
3171 kfree((*classes)[i]);
3172 kfree(*classes);
3173 }
3174
3175out:
3176 read_unlock(&state->ss->policy_rwlock);
3177 return rc;
3178}
3179
3180static int get_permissions_callback(void *k, void *d, void *args)
3181{
3182 struct perm_datum *datum = d;
3183 char *name = k, **perms = args;
3184 int value = datum->value - 1;
3185
3186 perms[value] = kstrdup(name, GFP_ATOMIC);
3187 if (!perms[value])
3188 return -ENOMEM;
3189
3190 return 0;
3191}
3192
3193int security_get_permissions(struct selinux_state *state,
3194 char *class, char ***perms, int *nperms)
3195{
3196 struct policydb *policydb = &state->ss->policydb;
3197 int rc, i;
3198 struct class_datum *match;
3199
3200 read_lock(&state->ss->policy_rwlock);
3201
3202 rc = -EINVAL;
3203 match = hashtab_search(policydb->p_classes.table, class);
3204 if (!match) {
3205 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
3206 __func__, class);
3207 goto out;
3208 }
3209
3210 rc = -ENOMEM;
3211 *nperms = match->permissions.nprim;
3212 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
3213 if (!*perms)
3214 goto out;
3215
3216 if (match->comdatum) {
3217 rc = hashtab_map(match->comdatum->permissions.table,
3218 get_permissions_callback, *perms);
3219 if (rc)
3220 goto err;
3221 }
3222
3223 rc = hashtab_map(match->permissions.table, get_permissions_callback,
3224 *perms);
3225 if (rc)
3226 goto err;
3227
3228out:
3229 read_unlock(&state->ss->policy_rwlock);
3230 return rc;
3231
3232err:
3233 read_unlock(&state->ss->policy_rwlock);
3234 for (i = 0; i < *nperms; i++)
3235 kfree((*perms)[i]);
3236 kfree(*perms);
3237 return rc;
3238}
3239
3240int security_get_reject_unknown(struct selinux_state *state)
3241{
3242 return state->ss->policydb.reject_unknown;
3243}
3244
3245int security_get_allow_unknown(struct selinux_state *state)
3246{
3247 return state->ss->policydb.allow_unknown;
3248}
3249
3250/**
3251 * security_policycap_supported - Check for a specific policy capability
3252 * @req_cap: capability
3253 *
3254 * Description:
3255 * This function queries the currently loaded policy to see if it supports the
3256 * capability specified by @req_cap. Returns true (1) if the capability is
3257 * supported, false (0) if it isn't supported.
3258 *
3259 */
3260int security_policycap_supported(struct selinux_state *state,
3261 unsigned int req_cap)
3262{
3263 struct policydb *policydb = &state->ss->policydb;
3264 int rc;
3265
3266 read_lock(&state->ss->policy_rwlock);
3267 rc = ebitmap_get_bit(&policydb->policycaps, req_cap);
3268 read_unlock(&state->ss->policy_rwlock);
3269
3270 return rc;
3271}
3272
3273struct selinux_audit_rule {
3274 u32 au_seqno;
3275 struct context au_ctxt;
3276};
3277
3278void selinux_audit_rule_free(void *vrule)
3279{
3280 struct selinux_audit_rule *rule = vrule;
3281
3282 if (rule) {
3283 context_destroy(&rule->au_ctxt);
3284 kfree(rule);
3285 }
3286}
3287
3288int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3289{
3290 struct selinux_state *state = &selinux_state;
3291 struct policydb *policydb = &state->ss->policydb;
3292 struct selinux_audit_rule *tmprule;
3293 struct role_datum *roledatum;
3294 struct type_datum *typedatum;
3295 struct user_datum *userdatum;
3296 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
3297 int rc = 0;
3298
3299 *rule = NULL;
3300
3301 if (!state->initialized)
3302 return -EOPNOTSUPP;
3303
3304 switch (field) {
3305 case AUDIT_SUBJ_USER:
3306 case AUDIT_SUBJ_ROLE:
3307 case AUDIT_SUBJ_TYPE:
3308 case AUDIT_OBJ_USER:
3309 case AUDIT_OBJ_ROLE:
3310 case AUDIT_OBJ_TYPE:
3311 /* only 'equals' and 'not equals' fit user, role, and type */
3312 if (op != Audit_equal && op != Audit_not_equal)
3313 return -EINVAL;
3314 break;
3315 case AUDIT_SUBJ_SEN:
3316 case AUDIT_SUBJ_CLR:
3317 case AUDIT_OBJ_LEV_LOW:
3318 case AUDIT_OBJ_LEV_HIGH:
3319 /* we do not allow a range, indicated by the presence of '-' */
3320 if (strchr(rulestr, '-'))
3321 return -EINVAL;
3322 break;
3323 default:
3324 /* only the above fields are valid */
3325 return -EINVAL;
3326 }
3327
3328 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
3329 if (!tmprule)
3330 return -ENOMEM;
3331
3332 context_init(&tmprule->au_ctxt);
3333
3334 read_lock(&state->ss->policy_rwlock);
3335
3336 tmprule->au_seqno = state->ss->latest_granting;
3337
3338 switch (field) {
3339 case AUDIT_SUBJ_USER:
3340 case AUDIT_OBJ_USER:
3341 rc = -EINVAL;
3342 userdatum = hashtab_search(policydb->p_users.table, rulestr);
3343 if (!userdatum)
3344 goto out;
3345 tmprule->au_ctxt.user = userdatum->value;
3346 break;
3347 case AUDIT_SUBJ_ROLE:
3348 case AUDIT_OBJ_ROLE:
3349 rc = -EINVAL;
3350 roledatum = hashtab_search(policydb->p_roles.table, rulestr);
3351 if (!roledatum)
3352 goto out;
3353 tmprule->au_ctxt.role = roledatum->value;
3354 break;
3355 case AUDIT_SUBJ_TYPE:
3356 case AUDIT_OBJ_TYPE:
3357 rc = -EINVAL;
3358 typedatum = hashtab_search(policydb->p_types.table, rulestr);
3359 if (!typedatum)
3360 goto out;
3361 tmprule->au_ctxt.type = typedatum->value;
3362 break;
3363 case AUDIT_SUBJ_SEN:
3364 case AUDIT_SUBJ_CLR:
3365 case AUDIT_OBJ_LEV_LOW:
3366 case AUDIT_OBJ_LEV_HIGH:
3367 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt,
3368 GFP_ATOMIC);
3369 if (rc)
3370 goto out;
3371 break;
3372 }
3373 rc = 0;
3374out:
3375 read_unlock(&state->ss->policy_rwlock);
3376
3377 if (rc) {
3378 selinux_audit_rule_free(tmprule);
3379 tmprule = NULL;
3380 }
3381
3382 *rule = tmprule;
3383
3384 return rc;
3385}
3386
3387/* Check to see if the rule contains any selinux fields */
3388int selinux_audit_rule_known(struct audit_krule *rule)
3389{
3390 int i;
3391
3392 for (i = 0; i < rule->field_count; i++) {
3393 struct audit_field *f = &rule->fields[i];
3394 switch (f->type) {
3395 case AUDIT_SUBJ_USER:
3396 case AUDIT_SUBJ_ROLE:
3397 case AUDIT_SUBJ_TYPE:
3398 case AUDIT_SUBJ_SEN:
3399 case AUDIT_SUBJ_CLR:
3400 case AUDIT_OBJ_USER:
3401 case AUDIT_OBJ_ROLE:
3402 case AUDIT_OBJ_TYPE:
3403 case AUDIT_OBJ_LEV_LOW:
3404 case AUDIT_OBJ_LEV_HIGH:
3405 return 1;
3406 }
3407 }
3408
3409 return 0;
3410}
3411
3412int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
3413 struct audit_context *actx)
3414{
3415 struct selinux_state *state = &selinux_state;
3416 struct context *ctxt;
3417 struct mls_level *level;
3418 struct selinux_audit_rule *rule = vrule;
3419 int match = 0;
3420
3421 if (unlikely(!rule)) {
3422 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
3423 return -ENOENT;
3424 }
3425
3426 read_lock(&state->ss->policy_rwlock);
3427
3428 if (rule->au_seqno < state->ss->latest_granting) {
3429 match = -ESTALE;
3430 goto out;
3431 }
3432
3433 ctxt = sidtab_search(&state->ss->sidtab, sid);
3434 if (unlikely(!ctxt)) {
3435 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
3436 sid);
3437 match = -ENOENT;
3438 goto out;
3439 }
3440
3441 /* a field/op pair that is not caught here will simply fall through
3442 without a match */
3443 switch (field) {
3444 case AUDIT_SUBJ_USER:
3445 case AUDIT_OBJ_USER:
3446 switch (op) {
3447 case Audit_equal:
3448 match = (ctxt->user == rule->au_ctxt.user);
3449 break;
3450 case Audit_not_equal:
3451 match = (ctxt->user != rule->au_ctxt.user);
3452 break;
3453 }
3454 break;
3455 case AUDIT_SUBJ_ROLE:
3456 case AUDIT_OBJ_ROLE:
3457 switch (op) {
3458 case Audit_equal:
3459 match = (ctxt->role == rule->au_ctxt.role);
3460 break;
3461 case Audit_not_equal:
3462 match = (ctxt->role != rule->au_ctxt.role);
3463 break;
3464 }
3465 break;
3466 case AUDIT_SUBJ_TYPE:
3467 case AUDIT_OBJ_TYPE:
3468 switch (op) {
3469 case Audit_equal:
3470 match = (ctxt->type == rule->au_ctxt.type);
3471 break;
3472 case Audit_not_equal:
3473 match = (ctxt->type != rule->au_ctxt.type);
3474 break;
3475 }
3476 break;
3477 case AUDIT_SUBJ_SEN:
3478 case AUDIT_SUBJ_CLR:
3479 case AUDIT_OBJ_LEV_LOW:
3480 case AUDIT_OBJ_LEV_HIGH:
3481 level = ((field == AUDIT_SUBJ_SEN ||
3482 field == AUDIT_OBJ_LEV_LOW) ?
3483 &ctxt->range.level[0] : &ctxt->range.level[1]);
3484 switch (op) {
3485 case Audit_equal:
3486 match = mls_level_eq(&rule->au_ctxt.range.level[0],
3487 level);
3488 break;
3489 case Audit_not_equal:
3490 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
3491 level);
3492 break;
3493 case Audit_lt:
3494 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
3495 level) &&
3496 !mls_level_eq(&rule->au_ctxt.range.level[0],
3497 level));
3498 break;
3499 case Audit_le:
3500 match = mls_level_dom(&rule->au_ctxt.range.level[0],
3501 level);
3502 break;
3503 case Audit_gt:
3504 match = (mls_level_dom(level,
3505 &rule->au_ctxt.range.level[0]) &&
3506 !mls_level_eq(level,
3507 &rule->au_ctxt.range.level[0]));
3508 break;
3509 case Audit_ge:
3510 match = mls_level_dom(level,
3511 &rule->au_ctxt.range.level[0]);
3512 break;
3513 }
3514 }
3515
3516out:
3517 read_unlock(&state->ss->policy_rwlock);
3518 return match;
3519}
3520
3521static int (*aurule_callback)(void) = audit_update_lsm_rules;
3522
3523static int aurule_avc_callback(u32 event)
3524{
3525 int err = 0;
3526
3527 if (event == AVC_CALLBACK_RESET && aurule_callback)
3528 err = aurule_callback();
3529 return err;
3530}
3531
3532static int __init aurule_init(void)
3533{
3534 int err;
3535
3536 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET);
3537 if (err)
3538 panic("avc_add_callback() failed, error %d\n", err);
3539
3540 return err;
3541}
3542__initcall(aurule_init);
3543
3544#ifdef CONFIG_NETLABEL
3545/**
3546 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3547 * @secattr: the NetLabel packet security attributes
3548 * @sid: the SELinux SID
3549 *
3550 * Description:
3551 * Attempt to cache the context in @ctx, which was derived from the packet in
3552 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3553 * already been initialized.
3554 *
3555 */
3556static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3557 u32 sid)
3558{
3559 u32 *sid_cache;
3560
3561 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3562 if (sid_cache == NULL)
3563 return;
3564 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3565 if (secattr->cache == NULL) {
3566 kfree(sid_cache);
3567 return;
3568 }
3569
3570 *sid_cache = sid;
3571 secattr->cache->free = kfree;
3572 secattr->cache->data = sid_cache;
3573 secattr->flags |= NETLBL_SECATTR_CACHE;
3574}
3575
3576/**
3577 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3578 * @secattr: the NetLabel packet security attributes
3579 * @sid: the SELinux SID
3580 *
3581 * Description:
3582 * Convert the given NetLabel security attributes in @secattr into a
3583 * SELinux SID. If the @secattr field does not contain a full SELinux
3584 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the
3585 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3586 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3587 * conversion for future lookups. Returns zero on success, negative values on
3588 * failure.
3589 *
3590 */
3591int security_netlbl_secattr_to_sid(struct selinux_state *state,
3592 struct netlbl_lsm_secattr *secattr,
3593 u32 *sid)
3594{
3595 struct policydb *policydb = &state->ss->policydb;
3596 struct sidtab *sidtab = &state->ss->sidtab;
3597 int rc;
3598 struct context *ctx;
3599 struct context ctx_new;
3600
3601 if (!state->initialized) {
3602 *sid = SECSID_NULL;
3603 return 0;
3604 }
3605
3606 read_lock(&state->ss->policy_rwlock);
3607
3608 if (secattr->flags & NETLBL_SECATTR_CACHE)
3609 *sid = *(u32 *)secattr->cache->data;
3610 else if (secattr->flags & NETLBL_SECATTR_SECID)
3611 *sid = secattr->attr.secid;
3612 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3613 rc = -EIDRM;
3614 ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
3615 if (ctx == NULL)
3616 goto out;
3617
3618 context_init(&ctx_new);
3619 ctx_new.user = ctx->user;
3620 ctx_new.role = ctx->role;
3621 ctx_new.type = ctx->type;
3622 mls_import_netlbl_lvl(policydb, &ctx_new, secattr);
3623 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3624 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr);
3625 if (rc)
3626 goto out;
3627 }
3628 rc = -EIDRM;
3629 if (!mls_context_isvalid(policydb, &ctx_new))
3630 goto out_free;
3631
3632 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
3633 if (rc)
3634 goto out_free;
3635
3636 security_netlbl_cache_add(secattr, *sid);
3637
3638 ebitmap_destroy(&ctx_new.range.level[0].cat);
3639 } else
3640 *sid = SECSID_NULL;
3641
3642 read_unlock(&state->ss->policy_rwlock);
3643 return 0;
3644out_free:
3645 ebitmap_destroy(&ctx_new.range.level[0].cat);
3646out:
3647 read_unlock(&state->ss->policy_rwlock);
3648 return rc;
3649}
3650
3651/**
3652 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3653 * @sid: the SELinux SID
3654 * @secattr: the NetLabel packet security attributes
3655 *
3656 * Description:
3657 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3658 * Returns zero on success, negative values on failure.
3659 *
3660 */
3661int security_netlbl_sid_to_secattr(struct selinux_state *state,
3662 u32 sid, struct netlbl_lsm_secattr *secattr)
3663{
3664 struct policydb *policydb = &state->ss->policydb;
3665 int rc;
3666 struct context *ctx;
3667
3668 if (!state->initialized)
3669 return 0;
3670
3671 read_lock(&state->ss->policy_rwlock);
3672
3673 rc = -ENOENT;
3674 ctx = sidtab_search(&state->ss->sidtab, sid);
3675 if (ctx == NULL)
3676 goto out;
3677
3678 rc = -ENOMEM;
3679 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1),
3680 GFP_ATOMIC);
3681 if (secattr->domain == NULL)
3682 goto out;
3683
3684 secattr->attr.secid = sid;
3685 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3686 mls_export_netlbl_lvl(policydb, ctx, secattr);
3687 rc = mls_export_netlbl_cat(policydb, ctx, secattr);
3688out:
3689 read_unlock(&state->ss->policy_rwlock);
3690 return rc;
3691}
3692#endif /* CONFIG_NETLABEL */
3693
3694/**
3695 * security_read_policy - read the policy.
3696 * @data: binary policy data
3697 * @len: length of data in bytes
3698 *
3699 */
3700int security_read_policy(struct selinux_state *state,
3701 void **data, size_t *len)
3702{
3703 struct policydb *policydb = &state->ss->policydb;
3704 int rc;
3705 struct policy_file fp;
3706
3707 if (!state->initialized)
3708 return -EINVAL;
3709
3710 *len = security_policydb_len(state);
3711
3712 *data = vmalloc_user(*len);
3713 if (!*data)
3714 return -ENOMEM;
3715
3716 fp.data = *data;
3717 fp.len = *len;
3718
3719 read_lock(&state->ss->policy_rwlock);
3720 rc = policydb_write(policydb, &fp);
3721 read_unlock(&state->ss->policy_rwlock);
3722
3723 if (rc)
3724 return rc;
3725
3726 *len = (unsigned long)fp.data - (unsigned long)*data;
3727 return 0;
3728
3729}