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1da177e4 LT |
1 | /* |
2 | * Implementation of the security services. | |
3 | * | |
4 | * Authors : Stephen Smalley, <sds@epoch.ncsc.mil> | |
5 | * James Morris <jmorris@redhat.com> | |
6 | * | |
7 | * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> | |
8 | * | |
9 | * Support for enhanced MLS infrastructure. | |
10 | * | |
11 | * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> | |
12 | * | |
13 | * Added conditional policy language extensions | |
14 | * | |
15 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. | |
16 | * Copyright (C) 2003 - 2004 Tresys Technology, LLC | |
17 | * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> | |
18 | * This program is free software; you can redistribute it and/or modify | |
19 | * it under the terms of the GNU General Public License as published by | |
20 | * the Free Software Foundation, version 2. | |
21 | */ | |
22 | #include <linux/kernel.h> | |
23 | #include <linux/slab.h> | |
24 | #include <linux/string.h> | |
25 | #include <linux/spinlock.h> | |
26 | #include <linux/errno.h> | |
27 | #include <linux/in.h> | |
28 | #include <linux/sched.h> | |
29 | #include <linux/audit.h> | |
30 | #include <asm/semaphore.h> | |
31 | #include "flask.h" | |
32 | #include "avc.h" | |
33 | #include "avc_ss.h" | |
34 | #include "security.h" | |
35 | #include "context.h" | |
36 | #include "policydb.h" | |
37 | #include "sidtab.h" | |
38 | #include "services.h" | |
39 | #include "conditional.h" | |
40 | #include "mls.h" | |
41 | ||
42 | extern void selnl_notify_policyload(u32 seqno); | |
43 | unsigned int policydb_loaded_version; | |
44 | ||
45 | static DEFINE_RWLOCK(policy_rwlock); | |
46 | #define POLICY_RDLOCK read_lock(&policy_rwlock) | |
47 | #define POLICY_WRLOCK write_lock_irq(&policy_rwlock) | |
48 | #define POLICY_RDUNLOCK read_unlock(&policy_rwlock) | |
49 | #define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock) | |
50 | ||
51 | static DECLARE_MUTEX(load_sem); | |
52 | #define LOAD_LOCK down(&load_sem) | |
53 | #define LOAD_UNLOCK up(&load_sem) | |
54 | ||
55 | static struct sidtab sidtab; | |
56 | struct policydb policydb; | |
57 | int ss_initialized = 0; | |
58 | ||
59 | /* | |
60 | * The largest sequence number that has been used when | |
61 | * providing an access decision to the access vector cache. | |
62 | * The sequence number only changes when a policy change | |
63 | * occurs. | |
64 | */ | |
65 | static u32 latest_granting = 0; | |
66 | ||
67 | /* Forward declaration. */ | |
68 | static int context_struct_to_string(struct context *context, char **scontext, | |
69 | u32 *scontext_len); | |
70 | ||
71 | /* | |
72 | * Return the boolean value of a constraint expression | |
73 | * when it is applied to the specified source and target | |
74 | * security contexts. | |
75 | * | |
76 | * xcontext is a special beast... It is used by the validatetrans rules | |
77 | * only. For these rules, scontext is the context before the transition, | |
78 | * tcontext is the context after the transition, and xcontext is the context | |
79 | * of the process performing the transition. All other callers of | |
80 | * constraint_expr_eval should pass in NULL for xcontext. | |
81 | */ | |
82 | static int constraint_expr_eval(struct context *scontext, | |
83 | struct context *tcontext, | |
84 | struct context *xcontext, | |
85 | struct constraint_expr *cexpr) | |
86 | { | |
87 | u32 val1, val2; | |
88 | struct context *c; | |
89 | struct role_datum *r1, *r2; | |
90 | struct mls_level *l1, *l2; | |
91 | struct constraint_expr *e; | |
92 | int s[CEXPR_MAXDEPTH]; | |
93 | int sp = -1; | |
94 | ||
95 | for (e = cexpr; e; e = e->next) { | |
96 | switch (e->expr_type) { | |
97 | case CEXPR_NOT: | |
98 | BUG_ON(sp < 0); | |
99 | s[sp] = !s[sp]; | |
100 | break; | |
101 | case CEXPR_AND: | |
102 | BUG_ON(sp < 1); | |
103 | sp--; | |
104 | s[sp] &= s[sp+1]; | |
105 | break; | |
106 | case CEXPR_OR: | |
107 | BUG_ON(sp < 1); | |
108 | sp--; | |
109 | s[sp] |= s[sp+1]; | |
110 | break; | |
111 | case CEXPR_ATTR: | |
112 | if (sp == (CEXPR_MAXDEPTH-1)) | |
113 | return 0; | |
114 | switch (e->attr) { | |
115 | case CEXPR_USER: | |
116 | val1 = scontext->user; | |
117 | val2 = tcontext->user; | |
118 | break; | |
119 | case CEXPR_TYPE: | |
120 | val1 = scontext->type; | |
121 | val2 = tcontext->type; | |
122 | break; | |
123 | case CEXPR_ROLE: | |
124 | val1 = scontext->role; | |
125 | val2 = tcontext->role; | |
126 | r1 = policydb.role_val_to_struct[val1 - 1]; | |
127 | r2 = policydb.role_val_to_struct[val2 - 1]; | |
128 | switch (e->op) { | |
129 | case CEXPR_DOM: | |
130 | s[++sp] = ebitmap_get_bit(&r1->dominates, | |
131 | val2 - 1); | |
132 | continue; | |
133 | case CEXPR_DOMBY: | |
134 | s[++sp] = ebitmap_get_bit(&r2->dominates, | |
135 | val1 - 1); | |
136 | continue; | |
137 | case CEXPR_INCOMP: | |
138 | s[++sp] = ( !ebitmap_get_bit(&r1->dominates, | |
139 | val2 - 1) && | |
140 | !ebitmap_get_bit(&r2->dominates, | |
141 | val1 - 1) ); | |
142 | continue; | |
143 | default: | |
144 | break; | |
145 | } | |
146 | break; | |
147 | case CEXPR_L1L2: | |
148 | l1 = &(scontext->range.level[0]); | |
149 | l2 = &(tcontext->range.level[0]); | |
150 | goto mls_ops; | |
151 | case CEXPR_L1H2: | |
152 | l1 = &(scontext->range.level[0]); | |
153 | l2 = &(tcontext->range.level[1]); | |
154 | goto mls_ops; | |
155 | case CEXPR_H1L2: | |
156 | l1 = &(scontext->range.level[1]); | |
157 | l2 = &(tcontext->range.level[0]); | |
158 | goto mls_ops; | |
159 | case CEXPR_H1H2: | |
160 | l1 = &(scontext->range.level[1]); | |
161 | l2 = &(tcontext->range.level[1]); | |
162 | goto mls_ops; | |
163 | case CEXPR_L1H1: | |
164 | l1 = &(scontext->range.level[0]); | |
165 | l2 = &(scontext->range.level[1]); | |
166 | goto mls_ops; | |
167 | case CEXPR_L2H2: | |
168 | l1 = &(tcontext->range.level[0]); | |
169 | l2 = &(tcontext->range.level[1]); | |
170 | goto mls_ops; | |
171 | mls_ops: | |
172 | switch (e->op) { | |
173 | case CEXPR_EQ: | |
174 | s[++sp] = mls_level_eq(l1, l2); | |
175 | continue; | |
176 | case CEXPR_NEQ: | |
177 | s[++sp] = !mls_level_eq(l1, l2); | |
178 | continue; | |
179 | case CEXPR_DOM: | |
180 | s[++sp] = mls_level_dom(l1, l2); | |
181 | continue; | |
182 | case CEXPR_DOMBY: | |
183 | s[++sp] = mls_level_dom(l2, l1); | |
184 | continue; | |
185 | case CEXPR_INCOMP: | |
186 | s[++sp] = mls_level_incomp(l2, l1); | |
187 | continue; | |
188 | default: | |
189 | BUG(); | |
190 | return 0; | |
191 | } | |
192 | break; | |
193 | default: | |
194 | BUG(); | |
195 | return 0; | |
196 | } | |
197 | ||
198 | switch (e->op) { | |
199 | case CEXPR_EQ: | |
200 | s[++sp] = (val1 == val2); | |
201 | break; | |
202 | case CEXPR_NEQ: | |
203 | s[++sp] = (val1 != val2); | |
204 | break; | |
205 | default: | |
206 | BUG(); | |
207 | return 0; | |
208 | } | |
209 | break; | |
210 | case CEXPR_NAMES: | |
211 | if (sp == (CEXPR_MAXDEPTH-1)) | |
212 | return 0; | |
213 | c = scontext; | |
214 | if (e->attr & CEXPR_TARGET) | |
215 | c = tcontext; | |
216 | else if (e->attr & CEXPR_XTARGET) { | |
217 | c = xcontext; | |
218 | if (!c) { | |
219 | BUG(); | |
220 | return 0; | |
221 | } | |
222 | } | |
223 | if (e->attr & CEXPR_USER) | |
224 | val1 = c->user; | |
225 | else if (e->attr & CEXPR_ROLE) | |
226 | val1 = c->role; | |
227 | else if (e->attr & CEXPR_TYPE) | |
228 | val1 = c->type; | |
229 | else { | |
230 | BUG(); | |
231 | return 0; | |
232 | } | |
233 | ||
234 | switch (e->op) { | |
235 | case CEXPR_EQ: | |
236 | s[++sp] = ebitmap_get_bit(&e->names, val1 - 1); | |
237 | break; | |
238 | case CEXPR_NEQ: | |
239 | s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1); | |
240 | break; | |
241 | default: | |
242 | BUG(); | |
243 | return 0; | |
244 | } | |
245 | break; | |
246 | default: | |
247 | BUG(); | |
248 | return 0; | |
249 | } | |
250 | } | |
251 | ||
252 | BUG_ON(sp != 0); | |
253 | return s[0]; | |
254 | } | |
255 | ||
256 | /* | |
257 | * Compute access vectors based on a context structure pair for | |
258 | * the permissions in a particular class. | |
259 | */ | |
260 | static int context_struct_compute_av(struct context *scontext, | |
261 | struct context *tcontext, | |
262 | u16 tclass, | |
263 | u32 requested, | |
264 | struct av_decision *avd) | |
265 | { | |
266 | struct constraint_node *constraint; | |
267 | struct role_allow *ra; | |
268 | struct avtab_key avkey; | |
782ebb99 | 269 | struct avtab_node *node; |
1da177e4 | 270 | struct class_datum *tclass_datum; |
782ebb99 SS |
271 | struct ebitmap *sattr, *tattr; |
272 | struct ebitmap_node *snode, *tnode; | |
273 | unsigned int i, j; | |
1da177e4 LT |
274 | |
275 | /* | |
276 | * Remap extended Netlink classes for old policy versions. | |
277 | * Do this here rather than socket_type_to_security_class() | |
278 | * in case a newer policy version is loaded, allowing sockets | |
279 | * to remain in the correct class. | |
280 | */ | |
281 | if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS) | |
282 | if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET && | |
283 | tclass <= SECCLASS_NETLINK_DNRT_SOCKET) | |
284 | tclass = SECCLASS_NETLINK_SOCKET; | |
285 | ||
286 | if (!tclass || tclass > policydb.p_classes.nprim) { | |
287 | printk(KERN_ERR "security_compute_av: unrecognized class %d\n", | |
288 | tclass); | |
289 | return -EINVAL; | |
290 | } | |
291 | tclass_datum = policydb.class_val_to_struct[tclass - 1]; | |
292 | ||
293 | /* | |
294 | * Initialize the access vectors to the default values. | |
295 | */ | |
296 | avd->allowed = 0; | |
297 | avd->decided = 0xffffffff; | |
298 | avd->auditallow = 0; | |
299 | avd->auditdeny = 0xffffffff; | |
300 | avd->seqno = latest_granting; | |
301 | ||
302 | /* | |
303 | * If a specific type enforcement rule was defined for | |
304 | * this permission check, then use it. | |
305 | */ | |
1da177e4 | 306 | avkey.target_class = tclass; |
782ebb99 SS |
307 | avkey.specified = AVTAB_AV; |
308 | sattr = &policydb.type_attr_map[scontext->type - 1]; | |
309 | tattr = &policydb.type_attr_map[tcontext->type - 1]; | |
310 | ebitmap_for_each_bit(sattr, snode, i) { | |
311 | if (!ebitmap_node_get_bit(snode, i)) | |
312 | continue; | |
313 | ebitmap_for_each_bit(tattr, tnode, j) { | |
314 | if (!ebitmap_node_get_bit(tnode, j)) | |
315 | continue; | |
316 | avkey.source_type = i + 1; | |
317 | avkey.target_type = j + 1; | |
318 | for (node = avtab_search_node(&policydb.te_avtab, &avkey); | |
319 | node != NULL; | |
320 | node = avtab_search_node_next(node, avkey.specified)) { | |
321 | if (node->key.specified == AVTAB_ALLOWED) | |
322 | avd->allowed |= node->datum.data; | |
323 | else if (node->key.specified == AVTAB_AUDITALLOW) | |
324 | avd->auditallow |= node->datum.data; | |
325 | else if (node->key.specified == AVTAB_AUDITDENY) | |
326 | avd->auditdeny &= node->datum.data; | |
327 | } | |
1da177e4 | 328 | |
782ebb99 SS |
329 | /* Check conditional av table for additional permissions */ |
330 | cond_compute_av(&policydb.te_cond_avtab, &avkey, avd); | |
331 | ||
332 | } | |
333 | } | |
1da177e4 LT |
334 | |
335 | /* | |
336 | * Remove any permissions prohibited by a constraint (this includes | |
337 | * the MLS policy). | |
338 | */ | |
339 | constraint = tclass_datum->constraints; | |
340 | while (constraint) { | |
341 | if ((constraint->permissions & (avd->allowed)) && | |
342 | !constraint_expr_eval(scontext, tcontext, NULL, | |
343 | constraint->expr)) { | |
344 | avd->allowed = (avd->allowed) & ~(constraint->permissions); | |
345 | } | |
346 | constraint = constraint->next; | |
347 | } | |
348 | ||
349 | /* | |
350 | * If checking process transition permission and the | |
351 | * role is changing, then check the (current_role, new_role) | |
352 | * pair. | |
353 | */ | |
354 | if (tclass == SECCLASS_PROCESS && | |
355 | (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) && | |
356 | scontext->role != tcontext->role) { | |
357 | for (ra = policydb.role_allow; ra; ra = ra->next) { | |
358 | if (scontext->role == ra->role && | |
359 | tcontext->role == ra->new_role) | |
360 | break; | |
361 | } | |
362 | if (!ra) | |
363 | avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION | | |
364 | PROCESS__DYNTRANSITION); | |
365 | } | |
366 | ||
367 | return 0; | |
368 | } | |
369 | ||
370 | static int security_validtrans_handle_fail(struct context *ocontext, | |
371 | struct context *ncontext, | |
372 | struct context *tcontext, | |
373 | u16 tclass) | |
374 | { | |
375 | char *o = NULL, *n = NULL, *t = NULL; | |
376 | u32 olen, nlen, tlen; | |
377 | ||
378 | if (context_struct_to_string(ocontext, &o, &olen) < 0) | |
379 | goto out; | |
380 | if (context_struct_to_string(ncontext, &n, &nlen) < 0) | |
381 | goto out; | |
382 | if (context_struct_to_string(tcontext, &t, &tlen) < 0) | |
383 | goto out; | |
9ad9ad38 | 384 | audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, |
1da177e4 LT |
385 | "security_validate_transition: denied for" |
386 | " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", | |
387 | o, n, t, policydb.p_class_val_to_name[tclass-1]); | |
388 | out: | |
389 | kfree(o); | |
390 | kfree(n); | |
391 | kfree(t); | |
392 | ||
393 | if (!selinux_enforcing) | |
394 | return 0; | |
395 | return -EPERM; | |
396 | } | |
397 | ||
398 | int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, | |
399 | u16 tclass) | |
400 | { | |
401 | struct context *ocontext; | |
402 | struct context *ncontext; | |
403 | struct context *tcontext; | |
404 | struct class_datum *tclass_datum; | |
405 | struct constraint_node *constraint; | |
406 | int rc = 0; | |
407 | ||
408 | if (!ss_initialized) | |
409 | return 0; | |
410 | ||
411 | POLICY_RDLOCK; | |
412 | ||
413 | /* | |
414 | * Remap extended Netlink classes for old policy versions. | |
415 | * Do this here rather than socket_type_to_security_class() | |
416 | * in case a newer policy version is loaded, allowing sockets | |
417 | * to remain in the correct class. | |
418 | */ | |
419 | if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS) | |
420 | if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET && | |
421 | tclass <= SECCLASS_NETLINK_DNRT_SOCKET) | |
422 | tclass = SECCLASS_NETLINK_SOCKET; | |
423 | ||
424 | if (!tclass || tclass > policydb.p_classes.nprim) { | |
425 | printk(KERN_ERR "security_validate_transition: " | |
426 | "unrecognized class %d\n", tclass); | |
427 | rc = -EINVAL; | |
428 | goto out; | |
429 | } | |
430 | tclass_datum = policydb.class_val_to_struct[tclass - 1]; | |
431 | ||
432 | ocontext = sidtab_search(&sidtab, oldsid); | |
433 | if (!ocontext) { | |
434 | printk(KERN_ERR "security_validate_transition: " | |
435 | " unrecognized SID %d\n", oldsid); | |
436 | rc = -EINVAL; | |
437 | goto out; | |
438 | } | |
439 | ||
440 | ncontext = sidtab_search(&sidtab, newsid); | |
441 | if (!ncontext) { | |
442 | printk(KERN_ERR "security_validate_transition: " | |
443 | " unrecognized SID %d\n", newsid); | |
444 | rc = -EINVAL; | |
445 | goto out; | |
446 | } | |
447 | ||
448 | tcontext = sidtab_search(&sidtab, tasksid); | |
449 | if (!tcontext) { | |
450 | printk(KERN_ERR "security_validate_transition: " | |
451 | " unrecognized SID %d\n", tasksid); | |
452 | rc = -EINVAL; | |
453 | goto out; | |
454 | } | |
455 | ||
456 | constraint = tclass_datum->validatetrans; | |
457 | while (constraint) { | |
458 | if (!constraint_expr_eval(ocontext, ncontext, tcontext, | |
459 | constraint->expr)) { | |
460 | rc = security_validtrans_handle_fail(ocontext, ncontext, | |
461 | tcontext, tclass); | |
462 | goto out; | |
463 | } | |
464 | constraint = constraint->next; | |
465 | } | |
466 | ||
467 | out: | |
468 | POLICY_RDUNLOCK; | |
469 | return rc; | |
470 | } | |
471 | ||
472 | /** | |
473 | * security_compute_av - Compute access vector decisions. | |
474 | * @ssid: source security identifier | |
475 | * @tsid: target security identifier | |
476 | * @tclass: target security class | |
477 | * @requested: requested permissions | |
478 | * @avd: access vector decisions | |
479 | * | |
480 | * Compute a set of access vector decisions based on the | |
481 | * SID pair (@ssid, @tsid) for the permissions in @tclass. | |
482 | * Return -%EINVAL if any of the parameters are invalid or %0 | |
483 | * if the access vector decisions were computed successfully. | |
484 | */ | |
485 | int security_compute_av(u32 ssid, | |
486 | u32 tsid, | |
487 | u16 tclass, | |
488 | u32 requested, | |
489 | struct av_decision *avd) | |
490 | { | |
491 | struct context *scontext = NULL, *tcontext = NULL; | |
492 | int rc = 0; | |
493 | ||
494 | if (!ss_initialized) { | |
4c443d1b SS |
495 | avd->allowed = 0xffffffff; |
496 | avd->decided = 0xffffffff; | |
1da177e4 LT |
497 | avd->auditallow = 0; |
498 | avd->auditdeny = 0xffffffff; | |
499 | avd->seqno = latest_granting; | |
500 | return 0; | |
501 | } | |
502 | ||
503 | POLICY_RDLOCK; | |
504 | ||
505 | scontext = sidtab_search(&sidtab, ssid); | |
506 | if (!scontext) { | |
507 | printk(KERN_ERR "security_compute_av: unrecognized SID %d\n", | |
508 | ssid); | |
509 | rc = -EINVAL; | |
510 | goto out; | |
511 | } | |
512 | tcontext = sidtab_search(&sidtab, tsid); | |
513 | if (!tcontext) { | |
514 | printk(KERN_ERR "security_compute_av: unrecognized SID %d\n", | |
515 | tsid); | |
516 | rc = -EINVAL; | |
517 | goto out; | |
518 | } | |
519 | ||
520 | rc = context_struct_compute_av(scontext, tcontext, tclass, | |
521 | requested, avd); | |
522 | out: | |
523 | POLICY_RDUNLOCK; | |
524 | return rc; | |
525 | } | |
526 | ||
527 | /* | |
528 | * Write the security context string representation of | |
529 | * the context structure `context' into a dynamically | |
530 | * allocated string of the correct size. Set `*scontext' | |
531 | * to point to this string and set `*scontext_len' to | |
532 | * the length of the string. | |
533 | */ | |
534 | static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len) | |
535 | { | |
536 | char *scontextp; | |
537 | ||
538 | *scontext = NULL; | |
539 | *scontext_len = 0; | |
540 | ||
541 | /* Compute the size of the context. */ | |
542 | *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1; | |
543 | *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1; | |
544 | *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1; | |
545 | *scontext_len += mls_compute_context_len(context); | |
546 | ||
547 | /* Allocate space for the context; caller must free this space. */ | |
548 | scontextp = kmalloc(*scontext_len, GFP_ATOMIC); | |
549 | if (!scontextp) { | |
550 | return -ENOMEM; | |
551 | } | |
552 | *scontext = scontextp; | |
553 | ||
554 | /* | |
555 | * Copy the user name, role name and type name into the context. | |
556 | */ | |
557 | sprintf(scontextp, "%s:%s:%s", | |
558 | policydb.p_user_val_to_name[context->user - 1], | |
559 | policydb.p_role_val_to_name[context->role - 1], | |
560 | policydb.p_type_val_to_name[context->type - 1]); | |
561 | scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) + | |
562 | 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) + | |
563 | 1 + strlen(policydb.p_type_val_to_name[context->type - 1]); | |
564 | ||
565 | mls_sid_to_context(context, &scontextp); | |
566 | ||
567 | *scontextp = 0; | |
568 | ||
569 | return 0; | |
570 | } | |
571 | ||
572 | #include "initial_sid_to_string.h" | |
573 | ||
574 | /** | |
575 | * security_sid_to_context - Obtain a context for a given SID. | |
576 | * @sid: security identifier, SID | |
577 | * @scontext: security context | |
578 | * @scontext_len: length in bytes | |
579 | * | |
580 | * Write the string representation of the context associated with @sid | |
581 | * into a dynamically allocated string of the correct size. Set @scontext | |
582 | * to point to this string and set @scontext_len to the length of the string. | |
583 | */ | |
584 | int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len) | |
585 | { | |
586 | struct context *context; | |
587 | int rc = 0; | |
588 | ||
589 | if (!ss_initialized) { | |
590 | if (sid <= SECINITSID_NUM) { | |
591 | char *scontextp; | |
592 | ||
593 | *scontext_len = strlen(initial_sid_to_string[sid]) + 1; | |
594 | scontextp = kmalloc(*scontext_len,GFP_ATOMIC); | |
595 | strcpy(scontextp, initial_sid_to_string[sid]); | |
596 | *scontext = scontextp; | |
597 | goto out; | |
598 | } | |
599 | printk(KERN_ERR "security_sid_to_context: called before initial " | |
600 | "load_policy on unknown SID %d\n", sid); | |
601 | rc = -EINVAL; | |
602 | goto out; | |
603 | } | |
604 | POLICY_RDLOCK; | |
605 | context = sidtab_search(&sidtab, sid); | |
606 | if (!context) { | |
607 | printk(KERN_ERR "security_sid_to_context: unrecognized SID " | |
608 | "%d\n", sid); | |
609 | rc = -EINVAL; | |
610 | goto out_unlock; | |
611 | } | |
612 | rc = context_struct_to_string(context, scontext, scontext_len); | |
613 | out_unlock: | |
614 | POLICY_RDUNLOCK; | |
615 | out: | |
616 | return rc; | |
617 | ||
618 | } | |
619 | ||
f5c1d5b2 | 620 | static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid) |
1da177e4 LT |
621 | { |
622 | char *scontext2; | |
623 | struct context context; | |
624 | struct role_datum *role; | |
625 | struct type_datum *typdatum; | |
626 | struct user_datum *usrdatum; | |
627 | char *scontextp, *p, oldc; | |
628 | int rc = 0; | |
629 | ||
630 | if (!ss_initialized) { | |
631 | int i; | |
632 | ||
633 | for (i = 1; i < SECINITSID_NUM; i++) { | |
634 | if (!strcmp(initial_sid_to_string[i], scontext)) { | |
635 | *sid = i; | |
636 | goto out; | |
637 | } | |
638 | } | |
639 | *sid = SECINITSID_KERNEL; | |
640 | goto out; | |
641 | } | |
642 | *sid = SECSID_NULL; | |
643 | ||
644 | /* Copy the string so that we can modify the copy as we parse it. | |
645 | The string should already by null terminated, but we append a | |
646 | null suffix to the copy to avoid problems with the existing | |
647 | attr package, which doesn't view the null terminator as part | |
648 | of the attribute value. */ | |
649 | scontext2 = kmalloc(scontext_len+1,GFP_KERNEL); | |
650 | if (!scontext2) { | |
651 | rc = -ENOMEM; | |
652 | goto out; | |
653 | } | |
654 | memcpy(scontext2, scontext, scontext_len); | |
655 | scontext2[scontext_len] = 0; | |
656 | ||
657 | context_init(&context); | |
658 | *sid = SECSID_NULL; | |
659 | ||
660 | POLICY_RDLOCK; | |
661 | ||
662 | /* Parse the security context. */ | |
663 | ||
664 | rc = -EINVAL; | |
665 | scontextp = (char *) scontext2; | |
666 | ||
667 | /* Extract the user. */ | |
668 | p = scontextp; | |
669 | while (*p && *p != ':') | |
670 | p++; | |
671 | ||
672 | if (*p == 0) | |
673 | goto out_unlock; | |
674 | ||
675 | *p++ = 0; | |
676 | ||
677 | usrdatum = hashtab_search(policydb.p_users.table, scontextp); | |
678 | if (!usrdatum) | |
679 | goto out_unlock; | |
680 | ||
681 | context.user = usrdatum->value; | |
682 | ||
683 | /* Extract role. */ | |
684 | scontextp = p; | |
685 | while (*p && *p != ':') | |
686 | p++; | |
687 | ||
688 | if (*p == 0) | |
689 | goto out_unlock; | |
690 | ||
691 | *p++ = 0; | |
692 | ||
693 | role = hashtab_search(policydb.p_roles.table, scontextp); | |
694 | if (!role) | |
695 | goto out_unlock; | |
696 | context.role = role->value; | |
697 | ||
698 | /* Extract type. */ | |
699 | scontextp = p; | |
700 | while (*p && *p != ':') | |
701 | p++; | |
702 | oldc = *p; | |
703 | *p++ = 0; | |
704 | ||
705 | typdatum = hashtab_search(policydb.p_types.table, scontextp); | |
706 | if (!typdatum) | |
707 | goto out_unlock; | |
708 | ||
709 | context.type = typdatum->value; | |
710 | ||
f5c1d5b2 | 711 | rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid); |
1da177e4 LT |
712 | if (rc) |
713 | goto out_unlock; | |
714 | ||
715 | if ((p - scontext2) < scontext_len) { | |
716 | rc = -EINVAL; | |
717 | goto out_unlock; | |
718 | } | |
719 | ||
720 | /* Check the validity of the new context. */ | |
721 | if (!policydb_context_isvalid(&policydb, &context)) { | |
722 | rc = -EINVAL; | |
723 | goto out_unlock; | |
724 | } | |
725 | /* Obtain the new sid. */ | |
726 | rc = sidtab_context_to_sid(&sidtab, &context, sid); | |
727 | out_unlock: | |
728 | POLICY_RDUNLOCK; | |
729 | context_destroy(&context); | |
730 | kfree(scontext2); | |
731 | out: | |
732 | return rc; | |
733 | } | |
734 | ||
f5c1d5b2 JM |
735 | /** |
736 | * security_context_to_sid - Obtain a SID for a given security context. | |
737 | * @scontext: security context | |
738 | * @scontext_len: length in bytes | |
739 | * @sid: security identifier, SID | |
740 | * | |
741 | * Obtains a SID associated with the security context that | |
742 | * has the string representation specified by @scontext. | |
743 | * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient | |
744 | * memory is available, or 0 on success. | |
745 | */ | |
746 | int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid) | |
747 | { | |
748 | return security_context_to_sid_core(scontext, scontext_len, | |
749 | sid, SECSID_NULL); | |
750 | } | |
751 | ||
752 | /** | |
753 | * security_context_to_sid_default - Obtain a SID for a given security context, | |
754 | * falling back to specified default if needed. | |
755 | * | |
756 | * @scontext: security context | |
757 | * @scontext_len: length in bytes | |
758 | * @sid: security identifier, SID | |
759 | * @def_sid: default SID to assign on errror | |
760 | * | |
761 | * Obtains a SID associated with the security context that | |
762 | * has the string representation specified by @scontext. | |
763 | * The default SID is passed to the MLS layer to be used to allow | |
764 | * kernel labeling of the MLS field if the MLS field is not present | |
765 | * (for upgrading to MLS without full relabel). | |
766 | * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient | |
767 | * memory is available, or 0 on success. | |
768 | */ | |
769 | int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid) | |
770 | { | |
771 | return security_context_to_sid_core(scontext, scontext_len, | |
772 | sid, def_sid); | |
773 | } | |
774 | ||
1da177e4 LT |
775 | static int compute_sid_handle_invalid_context( |
776 | struct context *scontext, | |
777 | struct context *tcontext, | |
778 | u16 tclass, | |
779 | struct context *newcontext) | |
780 | { | |
781 | char *s = NULL, *t = NULL, *n = NULL; | |
782 | u32 slen, tlen, nlen; | |
783 | ||
784 | if (context_struct_to_string(scontext, &s, &slen) < 0) | |
785 | goto out; | |
786 | if (context_struct_to_string(tcontext, &t, &tlen) < 0) | |
787 | goto out; | |
788 | if (context_struct_to_string(newcontext, &n, &nlen) < 0) | |
789 | goto out; | |
9ad9ad38 | 790 | audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, |
1da177e4 LT |
791 | "security_compute_sid: invalid context %s" |
792 | " for scontext=%s" | |
793 | " tcontext=%s" | |
794 | " tclass=%s", | |
795 | n, s, t, policydb.p_class_val_to_name[tclass-1]); | |
796 | out: | |
797 | kfree(s); | |
798 | kfree(t); | |
799 | kfree(n); | |
800 | if (!selinux_enforcing) | |
801 | return 0; | |
802 | return -EACCES; | |
803 | } | |
804 | ||
805 | static int security_compute_sid(u32 ssid, | |
806 | u32 tsid, | |
807 | u16 tclass, | |
808 | u32 specified, | |
809 | u32 *out_sid) | |
810 | { | |
811 | struct context *scontext = NULL, *tcontext = NULL, newcontext; | |
812 | struct role_trans *roletr = NULL; | |
813 | struct avtab_key avkey; | |
814 | struct avtab_datum *avdatum; | |
815 | struct avtab_node *node; | |
1da177e4 LT |
816 | int rc = 0; |
817 | ||
818 | if (!ss_initialized) { | |
819 | switch (tclass) { | |
820 | case SECCLASS_PROCESS: | |
821 | *out_sid = ssid; | |
822 | break; | |
823 | default: | |
824 | *out_sid = tsid; | |
825 | break; | |
826 | } | |
827 | goto out; | |
828 | } | |
829 | ||
830 | POLICY_RDLOCK; | |
831 | ||
832 | scontext = sidtab_search(&sidtab, ssid); | |
833 | if (!scontext) { | |
834 | printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n", | |
835 | ssid); | |
836 | rc = -EINVAL; | |
837 | goto out_unlock; | |
838 | } | |
839 | tcontext = sidtab_search(&sidtab, tsid); | |
840 | if (!tcontext) { | |
841 | printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n", | |
842 | tsid); | |
843 | rc = -EINVAL; | |
844 | goto out_unlock; | |
845 | } | |
846 | ||
847 | context_init(&newcontext); | |
848 | ||
849 | /* Set the user identity. */ | |
850 | switch (specified) { | |
851 | case AVTAB_TRANSITION: | |
852 | case AVTAB_CHANGE: | |
853 | /* Use the process user identity. */ | |
854 | newcontext.user = scontext->user; | |
855 | break; | |
856 | case AVTAB_MEMBER: | |
857 | /* Use the related object owner. */ | |
858 | newcontext.user = tcontext->user; | |
859 | break; | |
860 | } | |
861 | ||
862 | /* Set the role and type to default values. */ | |
863 | switch (tclass) { | |
864 | case SECCLASS_PROCESS: | |
865 | /* Use the current role and type of process. */ | |
866 | newcontext.role = scontext->role; | |
867 | newcontext.type = scontext->type; | |
868 | break; | |
869 | default: | |
870 | /* Use the well-defined object role. */ | |
871 | newcontext.role = OBJECT_R_VAL; | |
872 | /* Use the type of the related object. */ | |
873 | newcontext.type = tcontext->type; | |
874 | } | |
875 | ||
876 | /* Look for a type transition/member/change rule. */ | |
877 | avkey.source_type = scontext->type; | |
878 | avkey.target_type = tcontext->type; | |
879 | avkey.target_class = tclass; | |
782ebb99 SS |
880 | avkey.specified = specified; |
881 | avdatum = avtab_search(&policydb.te_avtab, &avkey); | |
1da177e4 LT |
882 | |
883 | /* If no permanent rule, also check for enabled conditional rules */ | |
884 | if(!avdatum) { | |
782ebb99 | 885 | node = avtab_search_node(&policydb.te_cond_avtab, &avkey); |
1da177e4 | 886 | for (; node != NULL; node = avtab_search_node_next(node, specified)) { |
782ebb99 | 887 | if (node->key.specified & AVTAB_ENABLED) { |
1da177e4 LT |
888 | avdatum = &node->datum; |
889 | break; | |
890 | } | |
891 | } | |
892 | } | |
893 | ||
782ebb99 | 894 | if (avdatum) { |
1da177e4 | 895 | /* Use the type from the type transition/member/change rule. */ |
782ebb99 | 896 | newcontext.type = avdatum->data; |
1da177e4 LT |
897 | } |
898 | ||
899 | /* Check for class-specific changes. */ | |
900 | switch (tclass) { | |
901 | case SECCLASS_PROCESS: | |
902 | if (specified & AVTAB_TRANSITION) { | |
903 | /* Look for a role transition rule. */ | |
904 | for (roletr = policydb.role_tr; roletr; | |
905 | roletr = roletr->next) { | |
906 | if (roletr->role == scontext->role && | |
907 | roletr->type == tcontext->type) { | |
908 | /* Use the role transition rule. */ | |
909 | newcontext.role = roletr->new_role; | |
910 | break; | |
911 | } | |
912 | } | |
913 | } | |
914 | break; | |
915 | default: | |
916 | break; | |
917 | } | |
918 | ||
919 | /* Set the MLS attributes. | |
920 | This is done last because it may allocate memory. */ | |
921 | rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext); | |
922 | if (rc) | |
923 | goto out_unlock; | |
924 | ||
925 | /* Check the validity of the context. */ | |
926 | if (!policydb_context_isvalid(&policydb, &newcontext)) { | |
927 | rc = compute_sid_handle_invalid_context(scontext, | |
928 | tcontext, | |
929 | tclass, | |
930 | &newcontext); | |
931 | if (rc) | |
932 | goto out_unlock; | |
933 | } | |
934 | /* Obtain the sid for the context. */ | |
935 | rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid); | |
936 | out_unlock: | |
937 | POLICY_RDUNLOCK; | |
938 | context_destroy(&newcontext); | |
939 | out: | |
940 | return rc; | |
941 | } | |
942 | ||
943 | /** | |
944 | * security_transition_sid - Compute the SID for a new subject/object. | |
945 | * @ssid: source security identifier | |
946 | * @tsid: target security identifier | |
947 | * @tclass: target security class | |
948 | * @out_sid: security identifier for new subject/object | |
949 | * | |
950 | * Compute a SID to use for labeling a new subject or object in the | |
951 | * class @tclass based on a SID pair (@ssid, @tsid). | |
952 | * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM | |
953 | * if insufficient memory is available, or %0 if the new SID was | |
954 | * computed successfully. | |
955 | */ | |
956 | int security_transition_sid(u32 ssid, | |
957 | u32 tsid, | |
958 | u16 tclass, | |
959 | u32 *out_sid) | |
960 | { | |
961 | return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid); | |
962 | } | |
963 | ||
964 | /** | |
965 | * security_member_sid - Compute the SID for member selection. | |
966 | * @ssid: source security identifier | |
967 | * @tsid: target security identifier | |
968 | * @tclass: target security class | |
969 | * @out_sid: security identifier for selected member | |
970 | * | |
971 | * Compute a SID to use when selecting a member of a polyinstantiated | |
972 | * object of class @tclass based on a SID pair (@ssid, @tsid). | |
973 | * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM | |
974 | * if insufficient memory is available, or %0 if the SID was | |
975 | * computed successfully. | |
976 | */ | |
977 | int security_member_sid(u32 ssid, | |
978 | u32 tsid, | |
979 | u16 tclass, | |
980 | u32 *out_sid) | |
981 | { | |
982 | return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid); | |
983 | } | |
984 | ||
985 | /** | |
986 | * security_change_sid - Compute the SID for object relabeling. | |
987 | * @ssid: source security identifier | |
988 | * @tsid: target security identifier | |
989 | * @tclass: target security class | |
990 | * @out_sid: security identifier for selected member | |
991 | * | |
992 | * Compute a SID to use for relabeling an object of class @tclass | |
993 | * based on a SID pair (@ssid, @tsid). | |
994 | * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM | |
995 | * if insufficient memory is available, or %0 if the SID was | |
996 | * computed successfully. | |
997 | */ | |
998 | int security_change_sid(u32 ssid, | |
999 | u32 tsid, | |
1000 | u16 tclass, | |
1001 | u32 *out_sid) | |
1002 | { | |
1003 | return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid); | |
1004 | } | |
1005 | ||
1006 | /* | |
1007 | * Verify that each permission that is defined under the | |
1008 | * existing policy is still defined with the same value | |
1009 | * in the new policy. | |
1010 | */ | |
1011 | static int validate_perm(void *key, void *datum, void *p) | |
1012 | { | |
1013 | struct hashtab *h; | |
1014 | struct perm_datum *perdatum, *perdatum2; | |
1015 | int rc = 0; | |
1016 | ||
1017 | ||
1018 | h = p; | |
1019 | perdatum = datum; | |
1020 | ||
1021 | perdatum2 = hashtab_search(h, key); | |
1022 | if (!perdatum2) { | |
1023 | printk(KERN_ERR "security: permission %s disappeared", | |
1024 | (char *)key); | |
1025 | rc = -ENOENT; | |
1026 | goto out; | |
1027 | } | |
1028 | if (perdatum->value != perdatum2->value) { | |
1029 | printk(KERN_ERR "security: the value of permission %s changed", | |
1030 | (char *)key); | |
1031 | rc = -EINVAL; | |
1032 | } | |
1033 | out: | |
1034 | return rc; | |
1035 | } | |
1036 | ||
1037 | /* | |
1038 | * Verify that each class that is defined under the | |
1039 | * existing policy is still defined with the same | |
1040 | * attributes in the new policy. | |
1041 | */ | |
1042 | static int validate_class(void *key, void *datum, void *p) | |
1043 | { | |
1044 | struct policydb *newp; | |
1045 | struct class_datum *cladatum, *cladatum2; | |
1046 | int rc; | |
1047 | ||
1048 | newp = p; | |
1049 | cladatum = datum; | |
1050 | ||
1051 | cladatum2 = hashtab_search(newp->p_classes.table, key); | |
1052 | if (!cladatum2) { | |
1053 | printk(KERN_ERR "security: class %s disappeared\n", | |
1054 | (char *)key); | |
1055 | rc = -ENOENT; | |
1056 | goto out; | |
1057 | } | |
1058 | if (cladatum->value != cladatum2->value) { | |
1059 | printk(KERN_ERR "security: the value of class %s changed\n", | |
1060 | (char *)key); | |
1061 | rc = -EINVAL; | |
1062 | goto out; | |
1063 | } | |
1064 | if ((cladatum->comdatum && !cladatum2->comdatum) || | |
1065 | (!cladatum->comdatum && cladatum2->comdatum)) { | |
1066 | printk(KERN_ERR "security: the inherits clause for the access " | |
1067 | "vector definition for class %s changed\n", (char *)key); | |
1068 | rc = -EINVAL; | |
1069 | goto out; | |
1070 | } | |
1071 | if (cladatum->comdatum) { | |
1072 | rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm, | |
1073 | cladatum2->comdatum->permissions.table); | |
1074 | if (rc) { | |
1075 | printk(" in the access vector definition for class " | |
1076 | "%s\n", (char *)key); | |
1077 | goto out; | |
1078 | } | |
1079 | } | |
1080 | rc = hashtab_map(cladatum->permissions.table, validate_perm, | |
1081 | cladatum2->permissions.table); | |
1082 | if (rc) | |
1083 | printk(" in access vector definition for class %s\n", | |
1084 | (char *)key); | |
1085 | out: | |
1086 | return rc; | |
1087 | } | |
1088 | ||
1089 | /* Clone the SID into the new SID table. */ | |
1090 | static int clone_sid(u32 sid, | |
1091 | struct context *context, | |
1092 | void *arg) | |
1093 | { | |
1094 | struct sidtab *s = arg; | |
1095 | ||
1096 | return sidtab_insert(s, sid, context); | |
1097 | } | |
1098 | ||
1099 | static inline int convert_context_handle_invalid_context(struct context *context) | |
1100 | { | |
1101 | int rc = 0; | |
1102 | ||
1103 | if (selinux_enforcing) { | |
1104 | rc = -EINVAL; | |
1105 | } else { | |
1106 | char *s; | |
1107 | u32 len; | |
1108 | ||
1109 | context_struct_to_string(context, &s, &len); | |
1110 | printk(KERN_ERR "security: context %s is invalid\n", s); | |
1111 | kfree(s); | |
1112 | } | |
1113 | return rc; | |
1114 | } | |
1115 | ||
1116 | struct convert_context_args { | |
1117 | struct policydb *oldp; | |
1118 | struct policydb *newp; | |
1119 | }; | |
1120 | ||
1121 | /* | |
1122 | * Convert the values in the security context | |
1123 | * structure `c' from the values specified | |
1124 | * in the policy `p->oldp' to the values specified | |
1125 | * in the policy `p->newp'. Verify that the | |
1126 | * context is valid under the new policy. | |
1127 | */ | |
1128 | static int convert_context(u32 key, | |
1129 | struct context *c, | |
1130 | void *p) | |
1131 | { | |
1132 | struct convert_context_args *args; | |
1133 | struct context oldc; | |
1134 | struct role_datum *role; | |
1135 | struct type_datum *typdatum; | |
1136 | struct user_datum *usrdatum; | |
1137 | char *s; | |
1138 | u32 len; | |
1139 | int rc; | |
1140 | ||
1141 | args = p; | |
1142 | ||
1143 | rc = context_cpy(&oldc, c); | |
1144 | if (rc) | |
1145 | goto out; | |
1146 | ||
1147 | rc = -EINVAL; | |
1148 | ||
1149 | /* Convert the user. */ | |
1150 | usrdatum = hashtab_search(args->newp->p_users.table, | |
1151 | args->oldp->p_user_val_to_name[c->user - 1]); | |
1152 | if (!usrdatum) { | |
1153 | goto bad; | |
1154 | } | |
1155 | c->user = usrdatum->value; | |
1156 | ||
1157 | /* Convert the role. */ | |
1158 | role = hashtab_search(args->newp->p_roles.table, | |
1159 | args->oldp->p_role_val_to_name[c->role - 1]); | |
1160 | if (!role) { | |
1161 | goto bad; | |
1162 | } | |
1163 | c->role = role->value; | |
1164 | ||
1165 | /* Convert the type. */ | |
1166 | typdatum = hashtab_search(args->newp->p_types.table, | |
1167 | args->oldp->p_type_val_to_name[c->type - 1]); | |
1168 | if (!typdatum) { | |
1169 | goto bad; | |
1170 | } | |
1171 | c->type = typdatum->value; | |
1172 | ||
1173 | rc = mls_convert_context(args->oldp, args->newp, c); | |
1174 | if (rc) | |
1175 | goto bad; | |
1176 | ||
1177 | /* Check the validity of the new context. */ | |
1178 | if (!policydb_context_isvalid(args->newp, c)) { | |
1179 | rc = convert_context_handle_invalid_context(&oldc); | |
1180 | if (rc) | |
1181 | goto bad; | |
1182 | } | |
1183 | ||
1184 | context_destroy(&oldc); | |
1185 | out: | |
1186 | return rc; | |
1187 | bad: | |
1188 | context_struct_to_string(&oldc, &s, &len); | |
1189 | context_destroy(&oldc); | |
1190 | printk(KERN_ERR "security: invalidating context %s\n", s); | |
1191 | kfree(s); | |
1192 | goto out; | |
1193 | } | |
1194 | ||
1195 | extern void selinux_complete_init(void); | |
1196 | ||
1197 | /** | |
1198 | * security_load_policy - Load a security policy configuration. | |
1199 | * @data: binary policy data | |
1200 | * @len: length of data in bytes | |
1201 | * | |
1202 | * Load a new set of security policy configuration data, | |
1203 | * validate it and convert the SID table as necessary. | |
1204 | * This function will flush the access vector cache after | |
1205 | * loading the new policy. | |
1206 | */ | |
1207 | int security_load_policy(void *data, size_t len) | |
1208 | { | |
1209 | struct policydb oldpolicydb, newpolicydb; | |
1210 | struct sidtab oldsidtab, newsidtab; | |
1211 | struct convert_context_args args; | |
1212 | u32 seqno; | |
1213 | int rc = 0; | |
1214 | struct policy_file file = { data, len }, *fp = &file; | |
1215 | ||
1216 | LOAD_LOCK; | |
1217 | ||
1218 | if (!ss_initialized) { | |
1219 | avtab_cache_init(); | |
1220 | if (policydb_read(&policydb, fp)) { | |
1221 | LOAD_UNLOCK; | |
1222 | avtab_cache_destroy(); | |
1223 | return -EINVAL; | |
1224 | } | |
1225 | if (policydb_load_isids(&policydb, &sidtab)) { | |
1226 | LOAD_UNLOCK; | |
1227 | policydb_destroy(&policydb); | |
1228 | avtab_cache_destroy(); | |
1229 | return -EINVAL; | |
1230 | } | |
1231 | policydb_loaded_version = policydb.policyvers; | |
1232 | ss_initialized = 1; | |
4c443d1b | 1233 | seqno = ++latest_granting; |
1da177e4 LT |
1234 | LOAD_UNLOCK; |
1235 | selinux_complete_init(); | |
4c443d1b SS |
1236 | avc_ss_reset(seqno); |
1237 | selnl_notify_policyload(seqno); | |
1da177e4 LT |
1238 | return 0; |
1239 | } | |
1240 | ||
1241 | #if 0 | |
1242 | sidtab_hash_eval(&sidtab, "sids"); | |
1243 | #endif | |
1244 | ||
1245 | if (policydb_read(&newpolicydb, fp)) { | |
1246 | LOAD_UNLOCK; | |
1247 | return -EINVAL; | |
1248 | } | |
1249 | ||
1250 | sidtab_init(&newsidtab); | |
1251 | ||
1252 | /* Verify that the existing classes did not change. */ | |
1253 | if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) { | |
1254 | printk(KERN_ERR "security: the definition of an existing " | |
1255 | "class changed\n"); | |
1256 | rc = -EINVAL; | |
1257 | goto err; | |
1258 | } | |
1259 | ||
1260 | /* Clone the SID table. */ | |
1261 | sidtab_shutdown(&sidtab); | |
1262 | if (sidtab_map(&sidtab, clone_sid, &newsidtab)) { | |
1263 | rc = -ENOMEM; | |
1264 | goto err; | |
1265 | } | |
1266 | ||
1267 | /* Convert the internal representations of contexts | |
1268 | in the new SID table and remove invalid SIDs. */ | |
1269 | args.oldp = &policydb; | |
1270 | args.newp = &newpolicydb; | |
1271 | sidtab_map_remove_on_error(&newsidtab, convert_context, &args); | |
1272 | ||
1273 | /* Save the old policydb and SID table to free later. */ | |
1274 | memcpy(&oldpolicydb, &policydb, sizeof policydb); | |
1275 | sidtab_set(&oldsidtab, &sidtab); | |
1276 | ||
1277 | /* Install the new policydb and SID table. */ | |
1278 | POLICY_WRLOCK; | |
1279 | memcpy(&policydb, &newpolicydb, sizeof policydb); | |
1280 | sidtab_set(&sidtab, &newsidtab); | |
1281 | seqno = ++latest_granting; | |
1282 | policydb_loaded_version = policydb.policyvers; | |
1283 | POLICY_WRUNLOCK; | |
1284 | LOAD_UNLOCK; | |
1285 | ||
1286 | /* Free the old policydb and SID table. */ | |
1287 | policydb_destroy(&oldpolicydb); | |
1288 | sidtab_destroy(&oldsidtab); | |
1289 | ||
1290 | avc_ss_reset(seqno); | |
1291 | selnl_notify_policyload(seqno); | |
1292 | ||
1293 | return 0; | |
1294 | ||
1295 | err: | |
1296 | LOAD_UNLOCK; | |
1297 | sidtab_destroy(&newsidtab); | |
1298 | policydb_destroy(&newpolicydb); | |
1299 | return rc; | |
1300 | ||
1301 | } | |
1302 | ||
1303 | /** | |
1304 | * security_port_sid - Obtain the SID for a port. | |
1305 | * @domain: communication domain aka address family | |
1306 | * @type: socket type | |
1307 | * @protocol: protocol number | |
1308 | * @port: port number | |
1309 | * @out_sid: security identifier | |
1310 | */ | |
1311 | int security_port_sid(u16 domain, | |
1312 | u16 type, | |
1313 | u8 protocol, | |
1314 | u16 port, | |
1315 | u32 *out_sid) | |
1316 | { | |
1317 | struct ocontext *c; | |
1318 | int rc = 0; | |
1319 | ||
1320 | POLICY_RDLOCK; | |
1321 | ||
1322 | c = policydb.ocontexts[OCON_PORT]; | |
1323 | while (c) { | |
1324 | if (c->u.port.protocol == protocol && | |
1325 | c->u.port.low_port <= port && | |
1326 | c->u.port.high_port >= port) | |
1327 | break; | |
1328 | c = c->next; | |
1329 | } | |
1330 | ||
1331 | if (c) { | |
1332 | if (!c->sid[0]) { | |
1333 | rc = sidtab_context_to_sid(&sidtab, | |
1334 | &c->context[0], | |
1335 | &c->sid[0]); | |
1336 | if (rc) | |
1337 | goto out; | |
1338 | } | |
1339 | *out_sid = c->sid[0]; | |
1340 | } else { | |
1341 | *out_sid = SECINITSID_PORT; | |
1342 | } | |
1343 | ||
1344 | out: | |
1345 | POLICY_RDUNLOCK; | |
1346 | return rc; | |
1347 | } | |
1348 | ||
1349 | /** | |
1350 | * security_netif_sid - Obtain the SID for a network interface. | |
1351 | * @name: interface name | |
1352 | * @if_sid: interface SID | |
1353 | * @msg_sid: default SID for received packets | |
1354 | */ | |
1355 | int security_netif_sid(char *name, | |
1356 | u32 *if_sid, | |
1357 | u32 *msg_sid) | |
1358 | { | |
1359 | int rc = 0; | |
1360 | struct ocontext *c; | |
1361 | ||
1362 | POLICY_RDLOCK; | |
1363 | ||
1364 | c = policydb.ocontexts[OCON_NETIF]; | |
1365 | while (c) { | |
1366 | if (strcmp(name, c->u.name) == 0) | |
1367 | break; | |
1368 | c = c->next; | |
1369 | } | |
1370 | ||
1371 | if (c) { | |
1372 | if (!c->sid[0] || !c->sid[1]) { | |
1373 | rc = sidtab_context_to_sid(&sidtab, | |
1374 | &c->context[0], | |
1375 | &c->sid[0]); | |
1376 | if (rc) | |
1377 | goto out; | |
1378 | rc = sidtab_context_to_sid(&sidtab, | |
1379 | &c->context[1], | |
1380 | &c->sid[1]); | |
1381 | if (rc) | |
1382 | goto out; | |
1383 | } | |
1384 | *if_sid = c->sid[0]; | |
1385 | *msg_sid = c->sid[1]; | |
1386 | } else { | |
1387 | *if_sid = SECINITSID_NETIF; | |
1388 | *msg_sid = SECINITSID_NETMSG; | |
1389 | } | |
1390 | ||
1391 | out: | |
1392 | POLICY_RDUNLOCK; | |
1393 | return rc; | |
1394 | } | |
1395 | ||
1396 | static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) | |
1397 | { | |
1398 | int i, fail = 0; | |
1399 | ||
1400 | for(i = 0; i < 4; i++) | |
1401 | if(addr[i] != (input[i] & mask[i])) { | |
1402 | fail = 1; | |
1403 | break; | |
1404 | } | |
1405 | ||
1406 | return !fail; | |
1407 | } | |
1408 | ||
1409 | /** | |
1410 | * security_node_sid - Obtain the SID for a node (host). | |
1411 | * @domain: communication domain aka address family | |
1412 | * @addrp: address | |
1413 | * @addrlen: address length in bytes | |
1414 | * @out_sid: security identifier | |
1415 | */ | |
1416 | int security_node_sid(u16 domain, | |
1417 | void *addrp, | |
1418 | u32 addrlen, | |
1419 | u32 *out_sid) | |
1420 | { | |
1421 | int rc = 0; | |
1422 | struct ocontext *c; | |
1423 | ||
1424 | POLICY_RDLOCK; | |
1425 | ||
1426 | switch (domain) { | |
1427 | case AF_INET: { | |
1428 | u32 addr; | |
1429 | ||
1430 | if (addrlen != sizeof(u32)) { | |
1431 | rc = -EINVAL; | |
1432 | goto out; | |
1433 | } | |
1434 | ||
1435 | addr = *((u32 *)addrp); | |
1436 | ||
1437 | c = policydb.ocontexts[OCON_NODE]; | |
1438 | while (c) { | |
1439 | if (c->u.node.addr == (addr & c->u.node.mask)) | |
1440 | break; | |
1441 | c = c->next; | |
1442 | } | |
1443 | break; | |
1444 | } | |
1445 | ||
1446 | case AF_INET6: | |
1447 | if (addrlen != sizeof(u64) * 2) { | |
1448 | rc = -EINVAL; | |
1449 | goto out; | |
1450 | } | |
1451 | c = policydb.ocontexts[OCON_NODE6]; | |
1452 | while (c) { | |
1453 | if (match_ipv6_addrmask(addrp, c->u.node6.addr, | |
1454 | c->u.node6.mask)) | |
1455 | break; | |
1456 | c = c->next; | |
1457 | } | |
1458 | break; | |
1459 | ||
1460 | default: | |
1461 | *out_sid = SECINITSID_NODE; | |
1462 | goto out; | |
1463 | } | |
1464 | ||
1465 | if (c) { | |
1466 | if (!c->sid[0]) { | |
1467 | rc = sidtab_context_to_sid(&sidtab, | |
1468 | &c->context[0], | |
1469 | &c->sid[0]); | |
1470 | if (rc) | |
1471 | goto out; | |
1472 | } | |
1473 | *out_sid = c->sid[0]; | |
1474 | } else { | |
1475 | *out_sid = SECINITSID_NODE; | |
1476 | } | |
1477 | ||
1478 | out: | |
1479 | POLICY_RDUNLOCK; | |
1480 | return rc; | |
1481 | } | |
1482 | ||
1483 | #define SIDS_NEL 25 | |
1484 | ||
1485 | /** | |
1486 | * security_get_user_sids - Obtain reachable SIDs for a user. | |
1487 | * @fromsid: starting SID | |
1488 | * @username: username | |
1489 | * @sids: array of reachable SIDs for user | |
1490 | * @nel: number of elements in @sids | |
1491 | * | |
1492 | * Generate the set of SIDs for legal security contexts | |
1493 | * for a given user that can be reached by @fromsid. | |
1494 | * Set *@sids to point to a dynamically allocated | |
1495 | * array containing the set of SIDs. Set *@nel to the | |
1496 | * number of elements in the array. | |
1497 | */ | |
1498 | ||
1499 | int security_get_user_sids(u32 fromsid, | |
1500 | char *username, | |
1501 | u32 **sids, | |
1502 | u32 *nel) | |
1503 | { | |
1504 | struct context *fromcon, usercon; | |
1505 | u32 *mysids, *mysids2, sid; | |
1506 | u32 mynel = 0, maxnel = SIDS_NEL; | |
1507 | struct user_datum *user; | |
1508 | struct role_datum *role; | |
1509 | struct av_decision avd; | |
782ebb99 | 1510 | struct ebitmap_node *rnode, *tnode; |
1da177e4 LT |
1511 | int rc = 0, i, j; |
1512 | ||
1513 | if (!ss_initialized) { | |
1514 | *sids = NULL; | |
1515 | *nel = 0; | |
1516 | goto out; | |
1517 | } | |
1518 | ||
1519 | POLICY_RDLOCK; | |
1520 | ||
1521 | fromcon = sidtab_search(&sidtab, fromsid); | |
1522 | if (!fromcon) { | |
1523 | rc = -EINVAL; | |
1524 | goto out_unlock; | |
1525 | } | |
1526 | ||
1527 | user = hashtab_search(policydb.p_users.table, username); | |
1528 | if (!user) { | |
1529 | rc = -EINVAL; | |
1530 | goto out_unlock; | |
1531 | } | |
1532 | usercon.user = user->value; | |
1533 | ||
89d155ef | 1534 | mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); |
1da177e4 LT |
1535 | if (!mysids) { |
1536 | rc = -ENOMEM; | |
1537 | goto out_unlock; | |
1538 | } | |
1da177e4 | 1539 | |
782ebb99 SS |
1540 | ebitmap_for_each_bit(&user->roles, rnode, i) { |
1541 | if (!ebitmap_node_get_bit(rnode, i)) | |
1da177e4 LT |
1542 | continue; |
1543 | role = policydb.role_val_to_struct[i]; | |
1544 | usercon.role = i+1; | |
782ebb99 SS |
1545 | ebitmap_for_each_bit(&role->types, tnode, j) { |
1546 | if (!ebitmap_node_get_bit(tnode, j)) | |
1da177e4 LT |
1547 | continue; |
1548 | usercon.type = j+1; | |
1549 | ||
1550 | if (mls_setup_user_range(fromcon, user, &usercon)) | |
1551 | continue; | |
1552 | ||
1553 | rc = context_struct_compute_av(fromcon, &usercon, | |
1554 | SECCLASS_PROCESS, | |
1555 | PROCESS__TRANSITION, | |
1556 | &avd); | |
1557 | if (rc || !(avd.allowed & PROCESS__TRANSITION)) | |
1558 | continue; | |
1559 | rc = sidtab_context_to_sid(&sidtab, &usercon, &sid); | |
1560 | if (rc) { | |
1561 | kfree(mysids); | |
1562 | goto out_unlock; | |
1563 | } | |
1564 | if (mynel < maxnel) { | |
1565 | mysids[mynel++] = sid; | |
1566 | } else { | |
1567 | maxnel += SIDS_NEL; | |
89d155ef | 1568 | mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC); |
1da177e4 LT |
1569 | if (!mysids2) { |
1570 | rc = -ENOMEM; | |
1571 | kfree(mysids); | |
1572 | goto out_unlock; | |
1573 | } | |
1da177e4 LT |
1574 | memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); |
1575 | kfree(mysids); | |
1576 | mysids = mysids2; | |
1577 | mysids[mynel++] = sid; | |
1578 | } | |
1579 | } | |
1580 | } | |
1581 | ||
1582 | *sids = mysids; | |
1583 | *nel = mynel; | |
1584 | ||
1585 | out_unlock: | |
1586 | POLICY_RDUNLOCK; | |
1587 | out: | |
1588 | return rc; | |
1589 | } | |
1590 | ||
1591 | /** | |
1592 | * security_genfs_sid - Obtain a SID for a file in a filesystem | |
1593 | * @fstype: filesystem type | |
1594 | * @path: path from root of mount | |
1595 | * @sclass: file security class | |
1596 | * @sid: SID for path | |
1597 | * | |
1598 | * Obtain a SID to use for a file in a filesystem that | |
1599 | * cannot support xattr or use a fixed labeling behavior like | |
1600 | * transition SIDs or task SIDs. | |
1601 | */ | |
1602 | int security_genfs_sid(const char *fstype, | |
1603 | char *path, | |
1604 | u16 sclass, | |
1605 | u32 *sid) | |
1606 | { | |
1607 | int len; | |
1608 | struct genfs *genfs; | |
1609 | struct ocontext *c; | |
1610 | int rc = 0, cmp = 0; | |
1611 | ||
1612 | POLICY_RDLOCK; | |
1613 | ||
1614 | for (genfs = policydb.genfs; genfs; genfs = genfs->next) { | |
1615 | cmp = strcmp(fstype, genfs->fstype); | |
1616 | if (cmp <= 0) | |
1617 | break; | |
1618 | } | |
1619 | ||
1620 | if (!genfs || cmp) { | |
1621 | *sid = SECINITSID_UNLABELED; | |
1622 | rc = -ENOENT; | |
1623 | goto out; | |
1624 | } | |
1625 | ||
1626 | for (c = genfs->head; c; c = c->next) { | |
1627 | len = strlen(c->u.name); | |
1628 | if ((!c->v.sclass || sclass == c->v.sclass) && | |
1629 | (strncmp(c->u.name, path, len) == 0)) | |
1630 | break; | |
1631 | } | |
1632 | ||
1633 | if (!c) { | |
1634 | *sid = SECINITSID_UNLABELED; | |
1635 | rc = -ENOENT; | |
1636 | goto out; | |
1637 | } | |
1638 | ||
1639 | if (!c->sid[0]) { | |
1640 | rc = sidtab_context_to_sid(&sidtab, | |
1641 | &c->context[0], | |
1642 | &c->sid[0]); | |
1643 | if (rc) | |
1644 | goto out; | |
1645 | } | |
1646 | ||
1647 | *sid = c->sid[0]; | |
1648 | out: | |
1649 | POLICY_RDUNLOCK; | |
1650 | return rc; | |
1651 | } | |
1652 | ||
1653 | /** | |
1654 | * security_fs_use - Determine how to handle labeling for a filesystem. | |
1655 | * @fstype: filesystem type | |
1656 | * @behavior: labeling behavior | |
1657 | * @sid: SID for filesystem (superblock) | |
1658 | */ | |
1659 | int security_fs_use( | |
1660 | const char *fstype, | |
1661 | unsigned int *behavior, | |
1662 | u32 *sid) | |
1663 | { | |
1664 | int rc = 0; | |
1665 | struct ocontext *c; | |
1666 | ||
1667 | POLICY_RDLOCK; | |
1668 | ||
1669 | c = policydb.ocontexts[OCON_FSUSE]; | |
1670 | while (c) { | |
1671 | if (strcmp(fstype, c->u.name) == 0) | |
1672 | break; | |
1673 | c = c->next; | |
1674 | } | |
1675 | ||
1676 | if (c) { | |
1677 | *behavior = c->v.behavior; | |
1678 | if (!c->sid[0]) { | |
1679 | rc = sidtab_context_to_sid(&sidtab, | |
1680 | &c->context[0], | |
1681 | &c->sid[0]); | |
1682 | if (rc) | |
1683 | goto out; | |
1684 | } | |
1685 | *sid = c->sid[0]; | |
1686 | } else { | |
1687 | rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid); | |
1688 | if (rc) { | |
1689 | *behavior = SECURITY_FS_USE_NONE; | |
1690 | rc = 0; | |
1691 | } else { | |
1692 | *behavior = SECURITY_FS_USE_GENFS; | |
1693 | } | |
1694 | } | |
1695 | ||
1696 | out: | |
1697 | POLICY_RDUNLOCK; | |
1698 | return rc; | |
1699 | } | |
1700 | ||
1701 | int security_get_bools(int *len, char ***names, int **values) | |
1702 | { | |
1703 | int i, rc = -ENOMEM; | |
1704 | ||
1705 | POLICY_RDLOCK; | |
1706 | *names = NULL; | |
1707 | *values = NULL; | |
1708 | ||
1709 | *len = policydb.p_bools.nprim; | |
1710 | if (!*len) { | |
1711 | rc = 0; | |
1712 | goto out; | |
1713 | } | |
1714 | ||
89d155ef | 1715 | *names = (char**)kcalloc(*len, sizeof(char*), GFP_ATOMIC); |
1da177e4 LT |
1716 | if (!*names) |
1717 | goto err; | |
1da177e4 | 1718 | |
89d155ef | 1719 | *values = (int*)kcalloc(*len, sizeof(int), GFP_ATOMIC); |
1da177e4 LT |
1720 | if (!*values) |
1721 | goto err; | |
1722 | ||
1723 | for (i = 0; i < *len; i++) { | |
1724 | size_t name_len; | |
1725 | (*values)[i] = policydb.bool_val_to_struct[i]->state; | |
1726 | name_len = strlen(policydb.p_bool_val_to_name[i]) + 1; | |
1727 | (*names)[i] = (char*)kmalloc(sizeof(char) * name_len, GFP_ATOMIC); | |
1728 | if (!(*names)[i]) | |
1729 | goto err; | |
1730 | strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len); | |
1731 | (*names)[i][name_len - 1] = 0; | |
1732 | } | |
1733 | rc = 0; | |
1734 | out: | |
1735 | POLICY_RDUNLOCK; | |
1736 | return rc; | |
1737 | err: | |
1738 | if (*names) { | |
1739 | for (i = 0; i < *len; i++) | |
9a5f04bf | 1740 | kfree((*names)[i]); |
1da177e4 | 1741 | } |
9a5f04bf | 1742 | kfree(*values); |
1da177e4 LT |
1743 | goto out; |
1744 | } | |
1745 | ||
1746 | ||
1747 | int security_set_bools(int len, int *values) | |
1748 | { | |
1749 | int i, rc = 0; | |
1750 | int lenp, seqno = 0; | |
1751 | struct cond_node *cur; | |
1752 | ||
1753 | POLICY_WRLOCK; | |
1754 | ||
1755 | lenp = policydb.p_bools.nprim; | |
1756 | if (len != lenp) { | |
1757 | rc = -EFAULT; | |
1758 | goto out; | |
1759 | } | |
1760 | ||
1761 | printk(KERN_INFO "security: committed booleans { "); | |
1762 | for (i = 0; i < len; i++) { | |
1763 | if (values[i]) { | |
1764 | policydb.bool_val_to_struct[i]->state = 1; | |
1765 | } else { | |
1766 | policydb.bool_val_to_struct[i]->state = 0; | |
1767 | } | |
1768 | if (i != 0) | |
1769 | printk(", "); | |
1770 | printk("%s:%d", policydb.p_bool_val_to_name[i], | |
1771 | policydb.bool_val_to_struct[i]->state); | |
1772 | } | |
1773 | printk(" }\n"); | |
1774 | ||
1775 | for (cur = policydb.cond_list; cur != NULL; cur = cur->next) { | |
1776 | rc = evaluate_cond_node(&policydb, cur); | |
1777 | if (rc) | |
1778 | goto out; | |
1779 | } | |
1780 | ||
1781 | seqno = ++latest_granting; | |
1782 | ||
1783 | out: | |
1784 | POLICY_WRUNLOCK; | |
1785 | if (!rc) { | |
1786 | avc_ss_reset(seqno); | |
1787 | selnl_notify_policyload(seqno); | |
1788 | } | |
1789 | return rc; | |
1790 | } | |
1791 | ||
1792 | int security_get_bool_value(int bool) | |
1793 | { | |
1794 | int rc = 0; | |
1795 | int len; | |
1796 | ||
1797 | POLICY_RDLOCK; | |
1798 | ||
1799 | len = policydb.p_bools.nprim; | |
1800 | if (bool >= len) { | |
1801 | rc = -EFAULT; | |
1802 | goto out; | |
1803 | } | |
1804 | ||
1805 | rc = policydb.bool_val_to_struct[bool]->state; | |
1806 | out: | |
1807 | POLICY_RDUNLOCK; | |
1808 | return rc; | |
1809 | } |