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Commit | Line | Data |
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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; | |
269 | struct avtab_datum *avdatum; | |
270 | struct class_datum *tclass_datum; | |
271 | ||
272 | /* | |
273 | * Remap extended Netlink classes for old policy versions. | |
274 | * Do this here rather than socket_type_to_security_class() | |
275 | * in case a newer policy version is loaded, allowing sockets | |
276 | * to remain in the correct class. | |
277 | */ | |
278 | if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS) | |
279 | if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET && | |
280 | tclass <= SECCLASS_NETLINK_DNRT_SOCKET) | |
281 | tclass = SECCLASS_NETLINK_SOCKET; | |
282 | ||
283 | if (!tclass || tclass > policydb.p_classes.nprim) { | |
284 | printk(KERN_ERR "security_compute_av: unrecognized class %d\n", | |
285 | tclass); | |
286 | return -EINVAL; | |
287 | } | |
288 | tclass_datum = policydb.class_val_to_struct[tclass - 1]; | |
289 | ||
290 | /* | |
291 | * Initialize the access vectors to the default values. | |
292 | */ | |
293 | avd->allowed = 0; | |
294 | avd->decided = 0xffffffff; | |
295 | avd->auditallow = 0; | |
296 | avd->auditdeny = 0xffffffff; | |
297 | avd->seqno = latest_granting; | |
298 | ||
299 | /* | |
300 | * If a specific type enforcement rule was defined for | |
301 | * this permission check, then use it. | |
302 | */ | |
303 | avkey.source_type = scontext->type; | |
304 | avkey.target_type = tcontext->type; | |
305 | avkey.target_class = tclass; | |
306 | avdatum = avtab_search(&policydb.te_avtab, &avkey, AVTAB_AV); | |
307 | if (avdatum) { | |
308 | if (avdatum->specified & AVTAB_ALLOWED) | |
309 | avd->allowed = avtab_allowed(avdatum); | |
310 | if (avdatum->specified & AVTAB_AUDITDENY) | |
311 | avd->auditdeny = avtab_auditdeny(avdatum); | |
312 | if (avdatum->specified & AVTAB_AUDITALLOW) | |
313 | avd->auditallow = avtab_auditallow(avdatum); | |
314 | } | |
315 | ||
316 | /* Check conditional av table for additional permissions */ | |
317 | cond_compute_av(&policydb.te_cond_avtab, &avkey, avd); | |
318 | ||
319 | /* | |
320 | * Remove any permissions prohibited by a constraint (this includes | |
321 | * the MLS policy). | |
322 | */ | |
323 | constraint = tclass_datum->constraints; | |
324 | while (constraint) { | |
325 | if ((constraint->permissions & (avd->allowed)) && | |
326 | !constraint_expr_eval(scontext, tcontext, NULL, | |
327 | constraint->expr)) { | |
328 | avd->allowed = (avd->allowed) & ~(constraint->permissions); | |
329 | } | |
330 | constraint = constraint->next; | |
331 | } | |
332 | ||
333 | /* | |
334 | * If checking process transition permission and the | |
335 | * role is changing, then check the (current_role, new_role) | |
336 | * pair. | |
337 | */ | |
338 | if (tclass == SECCLASS_PROCESS && | |
339 | (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) && | |
340 | scontext->role != tcontext->role) { | |
341 | for (ra = policydb.role_allow; ra; ra = ra->next) { | |
342 | if (scontext->role == ra->role && | |
343 | tcontext->role == ra->new_role) | |
344 | break; | |
345 | } | |
346 | if (!ra) | |
347 | avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION | | |
348 | PROCESS__DYNTRANSITION); | |
349 | } | |
350 | ||
351 | return 0; | |
352 | } | |
353 | ||
354 | static int security_validtrans_handle_fail(struct context *ocontext, | |
355 | struct context *ncontext, | |
356 | struct context *tcontext, | |
357 | u16 tclass) | |
358 | { | |
359 | char *o = NULL, *n = NULL, *t = NULL; | |
360 | u32 olen, nlen, tlen; | |
361 | ||
362 | if (context_struct_to_string(ocontext, &o, &olen) < 0) | |
363 | goto out; | |
364 | if (context_struct_to_string(ncontext, &n, &nlen) < 0) | |
365 | goto out; | |
366 | if (context_struct_to_string(tcontext, &t, &tlen) < 0) | |
367 | goto out; | |
c0404993 | 368 | audit_log(current->audit_context, AUDIT_SELINUX_ERR, |
1da177e4 LT |
369 | "security_validate_transition: denied for" |
370 | " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", | |
371 | o, n, t, policydb.p_class_val_to_name[tclass-1]); | |
372 | out: | |
373 | kfree(o); | |
374 | kfree(n); | |
375 | kfree(t); | |
376 | ||
377 | if (!selinux_enforcing) | |
378 | return 0; | |
379 | return -EPERM; | |
380 | } | |
381 | ||
382 | int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, | |
383 | u16 tclass) | |
384 | { | |
385 | struct context *ocontext; | |
386 | struct context *ncontext; | |
387 | struct context *tcontext; | |
388 | struct class_datum *tclass_datum; | |
389 | struct constraint_node *constraint; | |
390 | int rc = 0; | |
391 | ||
392 | if (!ss_initialized) | |
393 | return 0; | |
394 | ||
395 | POLICY_RDLOCK; | |
396 | ||
397 | /* | |
398 | * Remap extended Netlink classes for old policy versions. | |
399 | * Do this here rather than socket_type_to_security_class() | |
400 | * in case a newer policy version is loaded, allowing sockets | |
401 | * to remain in the correct class. | |
402 | */ | |
403 | if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS) | |
404 | if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET && | |
405 | tclass <= SECCLASS_NETLINK_DNRT_SOCKET) | |
406 | tclass = SECCLASS_NETLINK_SOCKET; | |
407 | ||
408 | if (!tclass || tclass > policydb.p_classes.nprim) { | |
409 | printk(KERN_ERR "security_validate_transition: " | |
410 | "unrecognized class %d\n", tclass); | |
411 | rc = -EINVAL; | |
412 | goto out; | |
413 | } | |
414 | tclass_datum = policydb.class_val_to_struct[tclass - 1]; | |
415 | ||
416 | ocontext = sidtab_search(&sidtab, oldsid); | |
417 | if (!ocontext) { | |
418 | printk(KERN_ERR "security_validate_transition: " | |
419 | " unrecognized SID %d\n", oldsid); | |
420 | rc = -EINVAL; | |
421 | goto out; | |
422 | } | |
423 | ||
424 | ncontext = sidtab_search(&sidtab, newsid); | |
425 | if (!ncontext) { | |
426 | printk(KERN_ERR "security_validate_transition: " | |
427 | " unrecognized SID %d\n", newsid); | |
428 | rc = -EINVAL; | |
429 | goto out; | |
430 | } | |
431 | ||
432 | tcontext = sidtab_search(&sidtab, tasksid); | |
433 | if (!tcontext) { | |
434 | printk(KERN_ERR "security_validate_transition: " | |
435 | " unrecognized SID %d\n", tasksid); | |
436 | rc = -EINVAL; | |
437 | goto out; | |
438 | } | |
439 | ||
440 | constraint = tclass_datum->validatetrans; | |
441 | while (constraint) { | |
442 | if (!constraint_expr_eval(ocontext, ncontext, tcontext, | |
443 | constraint->expr)) { | |
444 | rc = security_validtrans_handle_fail(ocontext, ncontext, | |
445 | tcontext, tclass); | |
446 | goto out; | |
447 | } | |
448 | constraint = constraint->next; | |
449 | } | |
450 | ||
451 | out: | |
452 | POLICY_RDUNLOCK; | |
453 | return rc; | |
454 | } | |
455 | ||
456 | /** | |
457 | * security_compute_av - Compute access vector decisions. | |
458 | * @ssid: source security identifier | |
459 | * @tsid: target security identifier | |
460 | * @tclass: target security class | |
461 | * @requested: requested permissions | |
462 | * @avd: access vector decisions | |
463 | * | |
464 | * Compute a set of access vector decisions based on the | |
465 | * SID pair (@ssid, @tsid) for the permissions in @tclass. | |
466 | * Return -%EINVAL if any of the parameters are invalid or %0 | |
467 | * if the access vector decisions were computed successfully. | |
468 | */ | |
469 | int security_compute_av(u32 ssid, | |
470 | u32 tsid, | |
471 | u16 tclass, | |
472 | u32 requested, | |
473 | struct av_decision *avd) | |
474 | { | |
475 | struct context *scontext = NULL, *tcontext = NULL; | |
476 | int rc = 0; | |
477 | ||
478 | if (!ss_initialized) { | |
4c443d1b SS |
479 | avd->allowed = 0xffffffff; |
480 | avd->decided = 0xffffffff; | |
1da177e4 LT |
481 | avd->auditallow = 0; |
482 | avd->auditdeny = 0xffffffff; | |
483 | avd->seqno = latest_granting; | |
484 | return 0; | |
485 | } | |
486 | ||
487 | POLICY_RDLOCK; | |
488 | ||
489 | scontext = sidtab_search(&sidtab, ssid); | |
490 | if (!scontext) { | |
491 | printk(KERN_ERR "security_compute_av: unrecognized SID %d\n", | |
492 | ssid); | |
493 | rc = -EINVAL; | |
494 | goto out; | |
495 | } | |
496 | tcontext = sidtab_search(&sidtab, tsid); | |
497 | if (!tcontext) { | |
498 | printk(KERN_ERR "security_compute_av: unrecognized SID %d\n", | |
499 | tsid); | |
500 | rc = -EINVAL; | |
501 | goto out; | |
502 | } | |
503 | ||
504 | rc = context_struct_compute_av(scontext, tcontext, tclass, | |
505 | requested, avd); | |
506 | out: | |
507 | POLICY_RDUNLOCK; | |
508 | return rc; | |
509 | } | |
510 | ||
511 | /* | |
512 | * Write the security context string representation of | |
513 | * the context structure `context' into a dynamically | |
514 | * allocated string of the correct size. Set `*scontext' | |
515 | * to point to this string and set `*scontext_len' to | |
516 | * the length of the string. | |
517 | */ | |
518 | static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len) | |
519 | { | |
520 | char *scontextp; | |
521 | ||
522 | *scontext = NULL; | |
523 | *scontext_len = 0; | |
524 | ||
525 | /* Compute the size of the context. */ | |
526 | *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1; | |
527 | *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1; | |
528 | *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1; | |
529 | *scontext_len += mls_compute_context_len(context); | |
530 | ||
531 | /* Allocate space for the context; caller must free this space. */ | |
532 | scontextp = kmalloc(*scontext_len, GFP_ATOMIC); | |
533 | if (!scontextp) { | |
534 | return -ENOMEM; | |
535 | } | |
536 | *scontext = scontextp; | |
537 | ||
538 | /* | |
539 | * Copy the user name, role name and type name into the context. | |
540 | */ | |
541 | sprintf(scontextp, "%s:%s:%s", | |
542 | policydb.p_user_val_to_name[context->user - 1], | |
543 | policydb.p_role_val_to_name[context->role - 1], | |
544 | policydb.p_type_val_to_name[context->type - 1]); | |
545 | scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) + | |
546 | 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) + | |
547 | 1 + strlen(policydb.p_type_val_to_name[context->type - 1]); | |
548 | ||
549 | mls_sid_to_context(context, &scontextp); | |
550 | ||
551 | *scontextp = 0; | |
552 | ||
553 | return 0; | |
554 | } | |
555 | ||
556 | #include "initial_sid_to_string.h" | |
557 | ||
558 | /** | |
559 | * security_sid_to_context - Obtain a context for a given SID. | |
560 | * @sid: security identifier, SID | |
561 | * @scontext: security context | |
562 | * @scontext_len: length in bytes | |
563 | * | |
564 | * Write the string representation of the context associated with @sid | |
565 | * into a dynamically allocated string of the correct size. Set @scontext | |
566 | * to point to this string and set @scontext_len to the length of the string. | |
567 | */ | |
568 | int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len) | |
569 | { | |
570 | struct context *context; | |
571 | int rc = 0; | |
572 | ||
573 | if (!ss_initialized) { | |
574 | if (sid <= SECINITSID_NUM) { | |
575 | char *scontextp; | |
576 | ||
577 | *scontext_len = strlen(initial_sid_to_string[sid]) + 1; | |
578 | scontextp = kmalloc(*scontext_len,GFP_ATOMIC); | |
579 | strcpy(scontextp, initial_sid_to_string[sid]); | |
580 | *scontext = scontextp; | |
581 | goto out; | |
582 | } | |
583 | printk(KERN_ERR "security_sid_to_context: called before initial " | |
584 | "load_policy on unknown SID %d\n", sid); | |
585 | rc = -EINVAL; | |
586 | goto out; | |
587 | } | |
588 | POLICY_RDLOCK; | |
589 | context = sidtab_search(&sidtab, sid); | |
590 | if (!context) { | |
591 | printk(KERN_ERR "security_sid_to_context: unrecognized SID " | |
592 | "%d\n", sid); | |
593 | rc = -EINVAL; | |
594 | goto out_unlock; | |
595 | } | |
596 | rc = context_struct_to_string(context, scontext, scontext_len); | |
597 | out_unlock: | |
598 | POLICY_RDUNLOCK; | |
599 | out: | |
600 | return rc; | |
601 | ||
602 | } | |
603 | ||
604 | /** | |
605 | * security_context_to_sid - Obtain a SID for a given security context. | |
606 | * @scontext: security context | |
607 | * @scontext_len: length in bytes | |
608 | * @sid: security identifier, SID | |
609 | * | |
610 | * Obtains a SID associated with the security context that | |
611 | * has the string representation specified by @scontext. | |
612 | * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient | |
613 | * memory is available, or 0 on success. | |
614 | */ | |
615 | int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid) | |
616 | { | |
617 | char *scontext2; | |
618 | struct context context; | |
619 | struct role_datum *role; | |
620 | struct type_datum *typdatum; | |
621 | struct user_datum *usrdatum; | |
622 | char *scontextp, *p, oldc; | |
623 | int rc = 0; | |
624 | ||
625 | if (!ss_initialized) { | |
626 | int i; | |
627 | ||
628 | for (i = 1; i < SECINITSID_NUM; i++) { | |
629 | if (!strcmp(initial_sid_to_string[i], scontext)) { | |
630 | *sid = i; | |
631 | goto out; | |
632 | } | |
633 | } | |
634 | *sid = SECINITSID_KERNEL; | |
635 | goto out; | |
636 | } | |
637 | *sid = SECSID_NULL; | |
638 | ||
639 | /* Copy the string so that we can modify the copy as we parse it. | |
640 | The string should already by null terminated, but we append a | |
641 | null suffix to the copy to avoid problems with the existing | |
642 | attr package, which doesn't view the null terminator as part | |
643 | of the attribute value. */ | |
644 | scontext2 = kmalloc(scontext_len+1,GFP_KERNEL); | |
645 | if (!scontext2) { | |
646 | rc = -ENOMEM; | |
647 | goto out; | |
648 | } | |
649 | memcpy(scontext2, scontext, scontext_len); | |
650 | scontext2[scontext_len] = 0; | |
651 | ||
652 | context_init(&context); | |
653 | *sid = SECSID_NULL; | |
654 | ||
655 | POLICY_RDLOCK; | |
656 | ||
657 | /* Parse the security context. */ | |
658 | ||
659 | rc = -EINVAL; | |
660 | scontextp = (char *) scontext2; | |
661 | ||
662 | /* Extract the user. */ | |
663 | p = scontextp; | |
664 | while (*p && *p != ':') | |
665 | p++; | |
666 | ||
667 | if (*p == 0) | |
668 | goto out_unlock; | |
669 | ||
670 | *p++ = 0; | |
671 | ||
672 | usrdatum = hashtab_search(policydb.p_users.table, scontextp); | |
673 | if (!usrdatum) | |
674 | goto out_unlock; | |
675 | ||
676 | context.user = usrdatum->value; | |
677 | ||
678 | /* Extract role. */ | |
679 | scontextp = p; | |
680 | while (*p && *p != ':') | |
681 | p++; | |
682 | ||
683 | if (*p == 0) | |
684 | goto out_unlock; | |
685 | ||
686 | *p++ = 0; | |
687 | ||
688 | role = hashtab_search(policydb.p_roles.table, scontextp); | |
689 | if (!role) | |
690 | goto out_unlock; | |
691 | context.role = role->value; | |
692 | ||
693 | /* Extract type. */ | |
694 | scontextp = p; | |
695 | while (*p && *p != ':') | |
696 | p++; | |
697 | oldc = *p; | |
698 | *p++ = 0; | |
699 | ||
700 | typdatum = hashtab_search(policydb.p_types.table, scontextp); | |
701 | if (!typdatum) | |
702 | goto out_unlock; | |
703 | ||
704 | context.type = typdatum->value; | |
705 | ||
706 | rc = mls_context_to_sid(oldc, &p, &context); | |
707 | if (rc) | |
708 | goto out_unlock; | |
709 | ||
710 | if ((p - scontext2) < scontext_len) { | |
711 | rc = -EINVAL; | |
712 | goto out_unlock; | |
713 | } | |
714 | ||
715 | /* Check the validity of the new context. */ | |
716 | if (!policydb_context_isvalid(&policydb, &context)) { | |
717 | rc = -EINVAL; | |
718 | goto out_unlock; | |
719 | } | |
720 | /* Obtain the new sid. */ | |
721 | rc = sidtab_context_to_sid(&sidtab, &context, sid); | |
722 | out_unlock: | |
723 | POLICY_RDUNLOCK; | |
724 | context_destroy(&context); | |
725 | kfree(scontext2); | |
726 | out: | |
727 | return rc; | |
728 | } | |
729 | ||
730 | static int compute_sid_handle_invalid_context( | |
731 | struct context *scontext, | |
732 | struct context *tcontext, | |
733 | u16 tclass, | |
734 | struct context *newcontext) | |
735 | { | |
736 | char *s = NULL, *t = NULL, *n = NULL; | |
737 | u32 slen, tlen, nlen; | |
738 | ||
739 | if (context_struct_to_string(scontext, &s, &slen) < 0) | |
740 | goto out; | |
741 | if (context_struct_to_string(tcontext, &t, &tlen) < 0) | |
742 | goto out; | |
743 | if (context_struct_to_string(newcontext, &n, &nlen) < 0) | |
744 | goto out; | |
c0404993 | 745 | audit_log(current->audit_context, AUDIT_SELINUX_ERR, |
1da177e4 LT |
746 | "security_compute_sid: invalid context %s" |
747 | " for scontext=%s" | |
748 | " tcontext=%s" | |
749 | " tclass=%s", | |
750 | n, s, t, policydb.p_class_val_to_name[tclass-1]); | |
751 | out: | |
752 | kfree(s); | |
753 | kfree(t); | |
754 | kfree(n); | |
755 | if (!selinux_enforcing) | |
756 | return 0; | |
757 | return -EACCES; | |
758 | } | |
759 | ||
760 | static int security_compute_sid(u32 ssid, | |
761 | u32 tsid, | |
762 | u16 tclass, | |
763 | u32 specified, | |
764 | u32 *out_sid) | |
765 | { | |
766 | struct context *scontext = NULL, *tcontext = NULL, newcontext; | |
767 | struct role_trans *roletr = NULL; | |
768 | struct avtab_key avkey; | |
769 | struct avtab_datum *avdatum; | |
770 | struct avtab_node *node; | |
771 | unsigned int type_change = 0; | |
772 | int rc = 0; | |
773 | ||
774 | if (!ss_initialized) { | |
775 | switch (tclass) { | |
776 | case SECCLASS_PROCESS: | |
777 | *out_sid = ssid; | |
778 | break; | |
779 | default: | |
780 | *out_sid = tsid; | |
781 | break; | |
782 | } | |
783 | goto out; | |
784 | } | |
785 | ||
786 | POLICY_RDLOCK; | |
787 | ||
788 | scontext = sidtab_search(&sidtab, ssid); | |
789 | if (!scontext) { | |
790 | printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n", | |
791 | ssid); | |
792 | rc = -EINVAL; | |
793 | goto out_unlock; | |
794 | } | |
795 | tcontext = sidtab_search(&sidtab, tsid); | |
796 | if (!tcontext) { | |
797 | printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n", | |
798 | tsid); | |
799 | rc = -EINVAL; | |
800 | goto out_unlock; | |
801 | } | |
802 | ||
803 | context_init(&newcontext); | |
804 | ||
805 | /* Set the user identity. */ | |
806 | switch (specified) { | |
807 | case AVTAB_TRANSITION: | |
808 | case AVTAB_CHANGE: | |
809 | /* Use the process user identity. */ | |
810 | newcontext.user = scontext->user; | |
811 | break; | |
812 | case AVTAB_MEMBER: | |
813 | /* Use the related object owner. */ | |
814 | newcontext.user = tcontext->user; | |
815 | break; | |
816 | } | |
817 | ||
818 | /* Set the role and type to default values. */ | |
819 | switch (tclass) { | |
820 | case SECCLASS_PROCESS: | |
821 | /* Use the current role and type of process. */ | |
822 | newcontext.role = scontext->role; | |
823 | newcontext.type = scontext->type; | |
824 | break; | |
825 | default: | |
826 | /* Use the well-defined object role. */ | |
827 | newcontext.role = OBJECT_R_VAL; | |
828 | /* Use the type of the related object. */ | |
829 | newcontext.type = tcontext->type; | |
830 | } | |
831 | ||
832 | /* Look for a type transition/member/change rule. */ | |
833 | avkey.source_type = scontext->type; | |
834 | avkey.target_type = tcontext->type; | |
835 | avkey.target_class = tclass; | |
836 | avdatum = avtab_search(&policydb.te_avtab, &avkey, AVTAB_TYPE); | |
837 | ||
838 | /* If no permanent rule, also check for enabled conditional rules */ | |
839 | if(!avdatum) { | |
840 | node = avtab_search_node(&policydb.te_cond_avtab, &avkey, specified); | |
841 | for (; node != NULL; node = avtab_search_node_next(node, specified)) { | |
842 | if (node->datum.specified & AVTAB_ENABLED) { | |
843 | avdatum = &node->datum; | |
844 | break; | |
845 | } | |
846 | } | |
847 | } | |
848 | ||
849 | type_change = (avdatum && (avdatum->specified & specified)); | |
850 | if (type_change) { | |
851 | /* Use the type from the type transition/member/change rule. */ | |
852 | switch (specified) { | |
853 | case AVTAB_TRANSITION: | |
854 | newcontext.type = avtab_transition(avdatum); | |
855 | break; | |
856 | case AVTAB_MEMBER: | |
857 | newcontext.type = avtab_member(avdatum); | |
858 | break; | |
859 | case AVTAB_CHANGE: | |
860 | newcontext.type = avtab_change(avdatum); | |
861 | break; | |
862 | } | |
863 | } | |
864 | ||
865 | /* Check for class-specific changes. */ | |
866 | switch (tclass) { | |
867 | case SECCLASS_PROCESS: | |
868 | if (specified & AVTAB_TRANSITION) { | |
869 | /* Look for a role transition rule. */ | |
870 | for (roletr = policydb.role_tr; roletr; | |
871 | roletr = roletr->next) { | |
872 | if (roletr->role == scontext->role && | |
873 | roletr->type == tcontext->type) { | |
874 | /* Use the role transition rule. */ | |
875 | newcontext.role = roletr->new_role; | |
876 | break; | |
877 | } | |
878 | } | |
879 | } | |
880 | break; | |
881 | default: | |
882 | break; | |
883 | } | |
884 | ||
885 | /* Set the MLS attributes. | |
886 | This is done last because it may allocate memory. */ | |
887 | rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext); | |
888 | if (rc) | |
889 | goto out_unlock; | |
890 | ||
891 | /* Check the validity of the context. */ | |
892 | if (!policydb_context_isvalid(&policydb, &newcontext)) { | |
893 | rc = compute_sid_handle_invalid_context(scontext, | |
894 | tcontext, | |
895 | tclass, | |
896 | &newcontext); | |
897 | if (rc) | |
898 | goto out_unlock; | |
899 | } | |
900 | /* Obtain the sid for the context. */ | |
901 | rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid); | |
902 | out_unlock: | |
903 | POLICY_RDUNLOCK; | |
904 | context_destroy(&newcontext); | |
905 | out: | |
906 | return rc; | |
907 | } | |
908 | ||
909 | /** | |
910 | * security_transition_sid - Compute the SID for a new subject/object. | |
911 | * @ssid: source security identifier | |
912 | * @tsid: target security identifier | |
913 | * @tclass: target security class | |
914 | * @out_sid: security identifier for new subject/object | |
915 | * | |
916 | * Compute a SID to use for labeling a new subject or object in the | |
917 | * class @tclass based on a SID pair (@ssid, @tsid). | |
918 | * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM | |
919 | * if insufficient memory is available, or %0 if the new SID was | |
920 | * computed successfully. | |
921 | */ | |
922 | int security_transition_sid(u32 ssid, | |
923 | u32 tsid, | |
924 | u16 tclass, | |
925 | u32 *out_sid) | |
926 | { | |
927 | return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid); | |
928 | } | |
929 | ||
930 | /** | |
931 | * security_member_sid - Compute the SID for member selection. | |
932 | * @ssid: source security identifier | |
933 | * @tsid: target security identifier | |
934 | * @tclass: target security class | |
935 | * @out_sid: security identifier for selected member | |
936 | * | |
937 | * Compute a SID to use when selecting a member of a polyinstantiated | |
938 | * object of class @tclass based on a SID pair (@ssid, @tsid). | |
939 | * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM | |
940 | * if insufficient memory is available, or %0 if the SID was | |
941 | * computed successfully. | |
942 | */ | |
943 | int security_member_sid(u32 ssid, | |
944 | u32 tsid, | |
945 | u16 tclass, | |
946 | u32 *out_sid) | |
947 | { | |
948 | return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid); | |
949 | } | |
950 | ||
951 | /** | |
952 | * security_change_sid - Compute the SID for object relabeling. | |
953 | * @ssid: source security identifier | |
954 | * @tsid: target security identifier | |
955 | * @tclass: target security class | |
956 | * @out_sid: security identifier for selected member | |
957 | * | |
958 | * Compute a SID to use for relabeling an object of class @tclass | |
959 | * based on a SID pair (@ssid, @tsid). | |
960 | * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM | |
961 | * if insufficient memory is available, or %0 if the SID was | |
962 | * computed successfully. | |
963 | */ | |
964 | int security_change_sid(u32 ssid, | |
965 | u32 tsid, | |
966 | u16 tclass, | |
967 | u32 *out_sid) | |
968 | { | |
969 | return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid); | |
970 | } | |
971 | ||
972 | /* | |
973 | * Verify that each permission that is defined under the | |
974 | * existing policy is still defined with the same value | |
975 | * in the new policy. | |
976 | */ | |
977 | static int validate_perm(void *key, void *datum, void *p) | |
978 | { | |
979 | struct hashtab *h; | |
980 | struct perm_datum *perdatum, *perdatum2; | |
981 | int rc = 0; | |
982 | ||
983 | ||
984 | h = p; | |
985 | perdatum = datum; | |
986 | ||
987 | perdatum2 = hashtab_search(h, key); | |
988 | if (!perdatum2) { | |
989 | printk(KERN_ERR "security: permission %s disappeared", | |
990 | (char *)key); | |
991 | rc = -ENOENT; | |
992 | goto out; | |
993 | } | |
994 | if (perdatum->value != perdatum2->value) { | |
995 | printk(KERN_ERR "security: the value of permission %s changed", | |
996 | (char *)key); | |
997 | rc = -EINVAL; | |
998 | } | |
999 | out: | |
1000 | return rc; | |
1001 | } | |
1002 | ||
1003 | /* | |
1004 | * Verify that each class that is defined under the | |
1005 | * existing policy is still defined with the same | |
1006 | * attributes in the new policy. | |
1007 | */ | |
1008 | static int validate_class(void *key, void *datum, void *p) | |
1009 | { | |
1010 | struct policydb *newp; | |
1011 | struct class_datum *cladatum, *cladatum2; | |
1012 | int rc; | |
1013 | ||
1014 | newp = p; | |
1015 | cladatum = datum; | |
1016 | ||
1017 | cladatum2 = hashtab_search(newp->p_classes.table, key); | |
1018 | if (!cladatum2) { | |
1019 | printk(KERN_ERR "security: class %s disappeared\n", | |
1020 | (char *)key); | |
1021 | rc = -ENOENT; | |
1022 | goto out; | |
1023 | } | |
1024 | if (cladatum->value != cladatum2->value) { | |
1025 | printk(KERN_ERR "security: the value of class %s changed\n", | |
1026 | (char *)key); | |
1027 | rc = -EINVAL; | |
1028 | goto out; | |
1029 | } | |
1030 | if ((cladatum->comdatum && !cladatum2->comdatum) || | |
1031 | (!cladatum->comdatum && cladatum2->comdatum)) { | |
1032 | printk(KERN_ERR "security: the inherits clause for the access " | |
1033 | "vector definition for class %s changed\n", (char *)key); | |
1034 | rc = -EINVAL; | |
1035 | goto out; | |
1036 | } | |
1037 | if (cladatum->comdatum) { | |
1038 | rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm, | |
1039 | cladatum2->comdatum->permissions.table); | |
1040 | if (rc) { | |
1041 | printk(" in the access vector definition for class " | |
1042 | "%s\n", (char *)key); | |
1043 | goto out; | |
1044 | } | |
1045 | } | |
1046 | rc = hashtab_map(cladatum->permissions.table, validate_perm, | |
1047 | cladatum2->permissions.table); | |
1048 | if (rc) | |
1049 | printk(" in access vector definition for class %s\n", | |
1050 | (char *)key); | |
1051 | out: | |
1052 | return rc; | |
1053 | } | |
1054 | ||
1055 | /* Clone the SID into the new SID table. */ | |
1056 | static int clone_sid(u32 sid, | |
1057 | struct context *context, | |
1058 | void *arg) | |
1059 | { | |
1060 | struct sidtab *s = arg; | |
1061 | ||
1062 | return sidtab_insert(s, sid, context); | |
1063 | } | |
1064 | ||
1065 | static inline int convert_context_handle_invalid_context(struct context *context) | |
1066 | { | |
1067 | int rc = 0; | |
1068 | ||
1069 | if (selinux_enforcing) { | |
1070 | rc = -EINVAL; | |
1071 | } else { | |
1072 | char *s; | |
1073 | u32 len; | |
1074 | ||
1075 | context_struct_to_string(context, &s, &len); | |
1076 | printk(KERN_ERR "security: context %s is invalid\n", s); | |
1077 | kfree(s); | |
1078 | } | |
1079 | return rc; | |
1080 | } | |
1081 | ||
1082 | struct convert_context_args { | |
1083 | struct policydb *oldp; | |
1084 | struct policydb *newp; | |
1085 | }; | |
1086 | ||
1087 | /* | |
1088 | * Convert the values in the security context | |
1089 | * structure `c' from the values specified | |
1090 | * in the policy `p->oldp' to the values specified | |
1091 | * in the policy `p->newp'. Verify that the | |
1092 | * context is valid under the new policy. | |
1093 | */ | |
1094 | static int convert_context(u32 key, | |
1095 | struct context *c, | |
1096 | void *p) | |
1097 | { | |
1098 | struct convert_context_args *args; | |
1099 | struct context oldc; | |
1100 | struct role_datum *role; | |
1101 | struct type_datum *typdatum; | |
1102 | struct user_datum *usrdatum; | |
1103 | char *s; | |
1104 | u32 len; | |
1105 | int rc; | |
1106 | ||
1107 | args = p; | |
1108 | ||
1109 | rc = context_cpy(&oldc, c); | |
1110 | if (rc) | |
1111 | goto out; | |
1112 | ||
1113 | rc = -EINVAL; | |
1114 | ||
1115 | /* Convert the user. */ | |
1116 | usrdatum = hashtab_search(args->newp->p_users.table, | |
1117 | args->oldp->p_user_val_to_name[c->user - 1]); | |
1118 | if (!usrdatum) { | |
1119 | goto bad; | |
1120 | } | |
1121 | c->user = usrdatum->value; | |
1122 | ||
1123 | /* Convert the role. */ | |
1124 | role = hashtab_search(args->newp->p_roles.table, | |
1125 | args->oldp->p_role_val_to_name[c->role - 1]); | |
1126 | if (!role) { | |
1127 | goto bad; | |
1128 | } | |
1129 | c->role = role->value; | |
1130 | ||
1131 | /* Convert the type. */ | |
1132 | typdatum = hashtab_search(args->newp->p_types.table, | |
1133 | args->oldp->p_type_val_to_name[c->type - 1]); | |
1134 | if (!typdatum) { | |
1135 | goto bad; | |
1136 | } | |
1137 | c->type = typdatum->value; | |
1138 | ||
1139 | rc = mls_convert_context(args->oldp, args->newp, c); | |
1140 | if (rc) | |
1141 | goto bad; | |
1142 | ||
1143 | /* Check the validity of the new context. */ | |
1144 | if (!policydb_context_isvalid(args->newp, c)) { | |
1145 | rc = convert_context_handle_invalid_context(&oldc); | |
1146 | if (rc) | |
1147 | goto bad; | |
1148 | } | |
1149 | ||
1150 | context_destroy(&oldc); | |
1151 | out: | |
1152 | return rc; | |
1153 | bad: | |
1154 | context_struct_to_string(&oldc, &s, &len); | |
1155 | context_destroy(&oldc); | |
1156 | printk(KERN_ERR "security: invalidating context %s\n", s); | |
1157 | kfree(s); | |
1158 | goto out; | |
1159 | } | |
1160 | ||
1161 | extern void selinux_complete_init(void); | |
1162 | ||
1163 | /** | |
1164 | * security_load_policy - Load a security policy configuration. | |
1165 | * @data: binary policy data | |
1166 | * @len: length of data in bytes | |
1167 | * | |
1168 | * Load a new set of security policy configuration data, | |
1169 | * validate it and convert the SID table as necessary. | |
1170 | * This function will flush the access vector cache after | |
1171 | * loading the new policy. | |
1172 | */ | |
1173 | int security_load_policy(void *data, size_t len) | |
1174 | { | |
1175 | struct policydb oldpolicydb, newpolicydb; | |
1176 | struct sidtab oldsidtab, newsidtab; | |
1177 | struct convert_context_args args; | |
1178 | u32 seqno; | |
1179 | int rc = 0; | |
1180 | struct policy_file file = { data, len }, *fp = &file; | |
1181 | ||
1182 | LOAD_LOCK; | |
1183 | ||
1184 | if (!ss_initialized) { | |
1185 | avtab_cache_init(); | |
1186 | if (policydb_read(&policydb, fp)) { | |
1187 | LOAD_UNLOCK; | |
1188 | avtab_cache_destroy(); | |
1189 | return -EINVAL; | |
1190 | } | |
1191 | if (policydb_load_isids(&policydb, &sidtab)) { | |
1192 | LOAD_UNLOCK; | |
1193 | policydb_destroy(&policydb); | |
1194 | avtab_cache_destroy(); | |
1195 | return -EINVAL; | |
1196 | } | |
1197 | policydb_loaded_version = policydb.policyvers; | |
1198 | ss_initialized = 1; | |
4c443d1b | 1199 | seqno = ++latest_granting; |
1da177e4 LT |
1200 | LOAD_UNLOCK; |
1201 | selinux_complete_init(); | |
4c443d1b SS |
1202 | avc_ss_reset(seqno); |
1203 | selnl_notify_policyload(seqno); | |
1da177e4 LT |
1204 | return 0; |
1205 | } | |
1206 | ||
1207 | #if 0 | |
1208 | sidtab_hash_eval(&sidtab, "sids"); | |
1209 | #endif | |
1210 | ||
1211 | if (policydb_read(&newpolicydb, fp)) { | |
1212 | LOAD_UNLOCK; | |
1213 | return -EINVAL; | |
1214 | } | |
1215 | ||
1216 | sidtab_init(&newsidtab); | |
1217 | ||
1218 | /* Verify that the existing classes did not change. */ | |
1219 | if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) { | |
1220 | printk(KERN_ERR "security: the definition of an existing " | |
1221 | "class changed\n"); | |
1222 | rc = -EINVAL; | |
1223 | goto err; | |
1224 | } | |
1225 | ||
1226 | /* Clone the SID table. */ | |
1227 | sidtab_shutdown(&sidtab); | |
1228 | if (sidtab_map(&sidtab, clone_sid, &newsidtab)) { | |
1229 | rc = -ENOMEM; | |
1230 | goto err; | |
1231 | } | |
1232 | ||
1233 | /* Convert the internal representations of contexts | |
1234 | in the new SID table and remove invalid SIDs. */ | |
1235 | args.oldp = &policydb; | |
1236 | args.newp = &newpolicydb; | |
1237 | sidtab_map_remove_on_error(&newsidtab, convert_context, &args); | |
1238 | ||
1239 | /* Save the old policydb and SID table to free later. */ | |
1240 | memcpy(&oldpolicydb, &policydb, sizeof policydb); | |
1241 | sidtab_set(&oldsidtab, &sidtab); | |
1242 | ||
1243 | /* Install the new policydb and SID table. */ | |
1244 | POLICY_WRLOCK; | |
1245 | memcpy(&policydb, &newpolicydb, sizeof policydb); | |
1246 | sidtab_set(&sidtab, &newsidtab); | |
1247 | seqno = ++latest_granting; | |
1248 | policydb_loaded_version = policydb.policyvers; | |
1249 | POLICY_WRUNLOCK; | |
1250 | LOAD_UNLOCK; | |
1251 | ||
1252 | /* Free the old policydb and SID table. */ | |
1253 | policydb_destroy(&oldpolicydb); | |
1254 | sidtab_destroy(&oldsidtab); | |
1255 | ||
1256 | avc_ss_reset(seqno); | |
1257 | selnl_notify_policyload(seqno); | |
1258 | ||
1259 | return 0; | |
1260 | ||
1261 | err: | |
1262 | LOAD_UNLOCK; | |
1263 | sidtab_destroy(&newsidtab); | |
1264 | policydb_destroy(&newpolicydb); | |
1265 | return rc; | |
1266 | ||
1267 | } | |
1268 | ||
1269 | /** | |
1270 | * security_port_sid - Obtain the SID for a port. | |
1271 | * @domain: communication domain aka address family | |
1272 | * @type: socket type | |
1273 | * @protocol: protocol number | |
1274 | * @port: port number | |
1275 | * @out_sid: security identifier | |
1276 | */ | |
1277 | int security_port_sid(u16 domain, | |
1278 | u16 type, | |
1279 | u8 protocol, | |
1280 | u16 port, | |
1281 | u32 *out_sid) | |
1282 | { | |
1283 | struct ocontext *c; | |
1284 | int rc = 0; | |
1285 | ||
1286 | POLICY_RDLOCK; | |
1287 | ||
1288 | c = policydb.ocontexts[OCON_PORT]; | |
1289 | while (c) { | |
1290 | if (c->u.port.protocol == protocol && | |
1291 | c->u.port.low_port <= port && | |
1292 | c->u.port.high_port >= port) | |
1293 | break; | |
1294 | c = c->next; | |
1295 | } | |
1296 | ||
1297 | if (c) { | |
1298 | if (!c->sid[0]) { | |
1299 | rc = sidtab_context_to_sid(&sidtab, | |
1300 | &c->context[0], | |
1301 | &c->sid[0]); | |
1302 | if (rc) | |
1303 | goto out; | |
1304 | } | |
1305 | *out_sid = c->sid[0]; | |
1306 | } else { | |
1307 | *out_sid = SECINITSID_PORT; | |
1308 | } | |
1309 | ||
1310 | out: | |
1311 | POLICY_RDUNLOCK; | |
1312 | return rc; | |
1313 | } | |
1314 | ||
1315 | /** | |
1316 | * security_netif_sid - Obtain the SID for a network interface. | |
1317 | * @name: interface name | |
1318 | * @if_sid: interface SID | |
1319 | * @msg_sid: default SID for received packets | |
1320 | */ | |
1321 | int security_netif_sid(char *name, | |
1322 | u32 *if_sid, | |
1323 | u32 *msg_sid) | |
1324 | { | |
1325 | int rc = 0; | |
1326 | struct ocontext *c; | |
1327 | ||
1328 | POLICY_RDLOCK; | |
1329 | ||
1330 | c = policydb.ocontexts[OCON_NETIF]; | |
1331 | while (c) { | |
1332 | if (strcmp(name, c->u.name) == 0) | |
1333 | break; | |
1334 | c = c->next; | |
1335 | } | |
1336 | ||
1337 | if (c) { | |
1338 | if (!c->sid[0] || !c->sid[1]) { | |
1339 | rc = sidtab_context_to_sid(&sidtab, | |
1340 | &c->context[0], | |
1341 | &c->sid[0]); | |
1342 | if (rc) | |
1343 | goto out; | |
1344 | rc = sidtab_context_to_sid(&sidtab, | |
1345 | &c->context[1], | |
1346 | &c->sid[1]); | |
1347 | if (rc) | |
1348 | goto out; | |
1349 | } | |
1350 | *if_sid = c->sid[0]; | |
1351 | *msg_sid = c->sid[1]; | |
1352 | } else { | |
1353 | *if_sid = SECINITSID_NETIF; | |
1354 | *msg_sid = SECINITSID_NETMSG; | |
1355 | } | |
1356 | ||
1357 | out: | |
1358 | POLICY_RDUNLOCK; | |
1359 | return rc; | |
1360 | } | |
1361 | ||
1362 | static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) | |
1363 | { | |
1364 | int i, fail = 0; | |
1365 | ||
1366 | for(i = 0; i < 4; i++) | |
1367 | if(addr[i] != (input[i] & mask[i])) { | |
1368 | fail = 1; | |
1369 | break; | |
1370 | } | |
1371 | ||
1372 | return !fail; | |
1373 | } | |
1374 | ||
1375 | /** | |
1376 | * security_node_sid - Obtain the SID for a node (host). | |
1377 | * @domain: communication domain aka address family | |
1378 | * @addrp: address | |
1379 | * @addrlen: address length in bytes | |
1380 | * @out_sid: security identifier | |
1381 | */ | |
1382 | int security_node_sid(u16 domain, | |
1383 | void *addrp, | |
1384 | u32 addrlen, | |
1385 | u32 *out_sid) | |
1386 | { | |
1387 | int rc = 0; | |
1388 | struct ocontext *c; | |
1389 | ||
1390 | POLICY_RDLOCK; | |
1391 | ||
1392 | switch (domain) { | |
1393 | case AF_INET: { | |
1394 | u32 addr; | |
1395 | ||
1396 | if (addrlen != sizeof(u32)) { | |
1397 | rc = -EINVAL; | |
1398 | goto out; | |
1399 | } | |
1400 | ||
1401 | addr = *((u32 *)addrp); | |
1402 | ||
1403 | c = policydb.ocontexts[OCON_NODE]; | |
1404 | while (c) { | |
1405 | if (c->u.node.addr == (addr & c->u.node.mask)) | |
1406 | break; | |
1407 | c = c->next; | |
1408 | } | |
1409 | break; | |
1410 | } | |
1411 | ||
1412 | case AF_INET6: | |
1413 | if (addrlen != sizeof(u64) * 2) { | |
1414 | rc = -EINVAL; | |
1415 | goto out; | |
1416 | } | |
1417 | c = policydb.ocontexts[OCON_NODE6]; | |
1418 | while (c) { | |
1419 | if (match_ipv6_addrmask(addrp, c->u.node6.addr, | |
1420 | c->u.node6.mask)) | |
1421 | break; | |
1422 | c = c->next; | |
1423 | } | |
1424 | break; | |
1425 | ||
1426 | default: | |
1427 | *out_sid = SECINITSID_NODE; | |
1428 | goto out; | |
1429 | } | |
1430 | ||
1431 | if (c) { | |
1432 | if (!c->sid[0]) { | |
1433 | rc = sidtab_context_to_sid(&sidtab, | |
1434 | &c->context[0], | |
1435 | &c->sid[0]); | |
1436 | if (rc) | |
1437 | goto out; | |
1438 | } | |
1439 | *out_sid = c->sid[0]; | |
1440 | } else { | |
1441 | *out_sid = SECINITSID_NODE; | |
1442 | } | |
1443 | ||
1444 | out: | |
1445 | POLICY_RDUNLOCK; | |
1446 | return rc; | |
1447 | } | |
1448 | ||
1449 | #define SIDS_NEL 25 | |
1450 | ||
1451 | /** | |
1452 | * security_get_user_sids - Obtain reachable SIDs for a user. | |
1453 | * @fromsid: starting SID | |
1454 | * @username: username | |
1455 | * @sids: array of reachable SIDs for user | |
1456 | * @nel: number of elements in @sids | |
1457 | * | |
1458 | * Generate the set of SIDs for legal security contexts | |
1459 | * for a given user that can be reached by @fromsid. | |
1460 | * Set *@sids to point to a dynamically allocated | |
1461 | * array containing the set of SIDs. Set *@nel to the | |
1462 | * number of elements in the array. | |
1463 | */ | |
1464 | ||
1465 | int security_get_user_sids(u32 fromsid, | |
1466 | char *username, | |
1467 | u32 **sids, | |
1468 | u32 *nel) | |
1469 | { | |
1470 | struct context *fromcon, usercon; | |
1471 | u32 *mysids, *mysids2, sid; | |
1472 | u32 mynel = 0, maxnel = SIDS_NEL; | |
1473 | struct user_datum *user; | |
1474 | struct role_datum *role; | |
1475 | struct av_decision avd; | |
1476 | int rc = 0, i, j; | |
1477 | ||
1478 | if (!ss_initialized) { | |
1479 | *sids = NULL; | |
1480 | *nel = 0; | |
1481 | goto out; | |
1482 | } | |
1483 | ||
1484 | POLICY_RDLOCK; | |
1485 | ||
1486 | fromcon = sidtab_search(&sidtab, fromsid); | |
1487 | if (!fromcon) { | |
1488 | rc = -EINVAL; | |
1489 | goto out_unlock; | |
1490 | } | |
1491 | ||
1492 | user = hashtab_search(policydb.p_users.table, username); | |
1493 | if (!user) { | |
1494 | rc = -EINVAL; | |
1495 | goto out_unlock; | |
1496 | } | |
1497 | usercon.user = user->value; | |
1498 | ||
1499 | mysids = kmalloc(maxnel*sizeof(*mysids), GFP_ATOMIC); | |
1500 | if (!mysids) { | |
1501 | rc = -ENOMEM; | |
1502 | goto out_unlock; | |
1503 | } | |
1504 | memset(mysids, 0, maxnel*sizeof(*mysids)); | |
1505 | ||
1506 | for (i = ebitmap_startbit(&user->roles); i < ebitmap_length(&user->roles); i++) { | |
1507 | if (!ebitmap_get_bit(&user->roles, i)) | |
1508 | continue; | |
1509 | role = policydb.role_val_to_struct[i]; | |
1510 | usercon.role = i+1; | |
1511 | for (j = ebitmap_startbit(&role->types); j < ebitmap_length(&role->types); j++) { | |
1512 | if (!ebitmap_get_bit(&role->types, j)) | |
1513 | continue; | |
1514 | usercon.type = j+1; | |
1515 | ||
1516 | if (mls_setup_user_range(fromcon, user, &usercon)) | |
1517 | continue; | |
1518 | ||
1519 | rc = context_struct_compute_av(fromcon, &usercon, | |
1520 | SECCLASS_PROCESS, | |
1521 | PROCESS__TRANSITION, | |
1522 | &avd); | |
1523 | if (rc || !(avd.allowed & PROCESS__TRANSITION)) | |
1524 | continue; | |
1525 | rc = sidtab_context_to_sid(&sidtab, &usercon, &sid); | |
1526 | if (rc) { | |
1527 | kfree(mysids); | |
1528 | goto out_unlock; | |
1529 | } | |
1530 | if (mynel < maxnel) { | |
1531 | mysids[mynel++] = sid; | |
1532 | } else { | |
1533 | maxnel += SIDS_NEL; | |
1534 | mysids2 = kmalloc(maxnel*sizeof(*mysids2), GFP_ATOMIC); | |
1535 | if (!mysids2) { | |
1536 | rc = -ENOMEM; | |
1537 | kfree(mysids); | |
1538 | goto out_unlock; | |
1539 | } | |
1540 | memset(mysids2, 0, maxnel*sizeof(*mysids2)); | |
1541 | memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); | |
1542 | kfree(mysids); | |
1543 | mysids = mysids2; | |
1544 | mysids[mynel++] = sid; | |
1545 | } | |
1546 | } | |
1547 | } | |
1548 | ||
1549 | *sids = mysids; | |
1550 | *nel = mynel; | |
1551 | ||
1552 | out_unlock: | |
1553 | POLICY_RDUNLOCK; | |
1554 | out: | |
1555 | return rc; | |
1556 | } | |
1557 | ||
1558 | /** | |
1559 | * security_genfs_sid - Obtain a SID for a file in a filesystem | |
1560 | * @fstype: filesystem type | |
1561 | * @path: path from root of mount | |
1562 | * @sclass: file security class | |
1563 | * @sid: SID for path | |
1564 | * | |
1565 | * Obtain a SID to use for a file in a filesystem that | |
1566 | * cannot support xattr or use a fixed labeling behavior like | |
1567 | * transition SIDs or task SIDs. | |
1568 | */ | |
1569 | int security_genfs_sid(const char *fstype, | |
1570 | char *path, | |
1571 | u16 sclass, | |
1572 | u32 *sid) | |
1573 | { | |
1574 | int len; | |
1575 | struct genfs *genfs; | |
1576 | struct ocontext *c; | |
1577 | int rc = 0, cmp = 0; | |
1578 | ||
1579 | POLICY_RDLOCK; | |
1580 | ||
1581 | for (genfs = policydb.genfs; genfs; genfs = genfs->next) { | |
1582 | cmp = strcmp(fstype, genfs->fstype); | |
1583 | if (cmp <= 0) | |
1584 | break; | |
1585 | } | |
1586 | ||
1587 | if (!genfs || cmp) { | |
1588 | *sid = SECINITSID_UNLABELED; | |
1589 | rc = -ENOENT; | |
1590 | goto out; | |
1591 | } | |
1592 | ||
1593 | for (c = genfs->head; c; c = c->next) { | |
1594 | len = strlen(c->u.name); | |
1595 | if ((!c->v.sclass || sclass == c->v.sclass) && | |
1596 | (strncmp(c->u.name, path, len) == 0)) | |
1597 | break; | |
1598 | } | |
1599 | ||
1600 | if (!c) { | |
1601 | *sid = SECINITSID_UNLABELED; | |
1602 | rc = -ENOENT; | |
1603 | goto out; | |
1604 | } | |
1605 | ||
1606 | if (!c->sid[0]) { | |
1607 | rc = sidtab_context_to_sid(&sidtab, | |
1608 | &c->context[0], | |
1609 | &c->sid[0]); | |
1610 | if (rc) | |
1611 | goto out; | |
1612 | } | |
1613 | ||
1614 | *sid = c->sid[0]; | |
1615 | out: | |
1616 | POLICY_RDUNLOCK; | |
1617 | return rc; | |
1618 | } | |
1619 | ||
1620 | /** | |
1621 | * security_fs_use - Determine how to handle labeling for a filesystem. | |
1622 | * @fstype: filesystem type | |
1623 | * @behavior: labeling behavior | |
1624 | * @sid: SID for filesystem (superblock) | |
1625 | */ | |
1626 | int security_fs_use( | |
1627 | const char *fstype, | |
1628 | unsigned int *behavior, | |
1629 | u32 *sid) | |
1630 | { | |
1631 | int rc = 0; | |
1632 | struct ocontext *c; | |
1633 | ||
1634 | POLICY_RDLOCK; | |
1635 | ||
1636 | c = policydb.ocontexts[OCON_FSUSE]; | |
1637 | while (c) { | |
1638 | if (strcmp(fstype, c->u.name) == 0) | |
1639 | break; | |
1640 | c = c->next; | |
1641 | } | |
1642 | ||
1643 | if (c) { | |
1644 | *behavior = c->v.behavior; | |
1645 | if (!c->sid[0]) { | |
1646 | rc = sidtab_context_to_sid(&sidtab, | |
1647 | &c->context[0], | |
1648 | &c->sid[0]); | |
1649 | if (rc) | |
1650 | goto out; | |
1651 | } | |
1652 | *sid = c->sid[0]; | |
1653 | } else { | |
1654 | rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid); | |
1655 | if (rc) { | |
1656 | *behavior = SECURITY_FS_USE_NONE; | |
1657 | rc = 0; | |
1658 | } else { | |
1659 | *behavior = SECURITY_FS_USE_GENFS; | |
1660 | } | |
1661 | } | |
1662 | ||
1663 | out: | |
1664 | POLICY_RDUNLOCK; | |
1665 | return rc; | |
1666 | } | |
1667 | ||
1668 | int security_get_bools(int *len, char ***names, int **values) | |
1669 | { | |
1670 | int i, rc = -ENOMEM; | |
1671 | ||
1672 | POLICY_RDLOCK; | |
1673 | *names = NULL; | |
1674 | *values = NULL; | |
1675 | ||
1676 | *len = policydb.p_bools.nprim; | |
1677 | if (!*len) { | |
1678 | rc = 0; | |
1679 | goto out; | |
1680 | } | |
1681 | ||
1682 | *names = (char**)kmalloc(sizeof(char*) * *len, GFP_ATOMIC); | |
1683 | if (!*names) | |
1684 | goto err; | |
1685 | memset(*names, 0, sizeof(char*) * *len); | |
1686 | ||
1687 | *values = (int*)kmalloc(sizeof(int) * *len, GFP_ATOMIC); | |
1688 | if (!*values) | |
1689 | goto err; | |
1690 | ||
1691 | for (i = 0; i < *len; i++) { | |
1692 | size_t name_len; | |
1693 | (*values)[i] = policydb.bool_val_to_struct[i]->state; | |
1694 | name_len = strlen(policydb.p_bool_val_to_name[i]) + 1; | |
1695 | (*names)[i] = (char*)kmalloc(sizeof(char) * name_len, GFP_ATOMIC); | |
1696 | if (!(*names)[i]) | |
1697 | goto err; | |
1698 | strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len); | |
1699 | (*names)[i][name_len - 1] = 0; | |
1700 | } | |
1701 | rc = 0; | |
1702 | out: | |
1703 | POLICY_RDUNLOCK; | |
1704 | return rc; | |
1705 | err: | |
1706 | if (*names) { | |
1707 | for (i = 0; i < *len; i++) | |
9a5f04bf | 1708 | kfree((*names)[i]); |
1da177e4 | 1709 | } |
9a5f04bf | 1710 | kfree(*values); |
1da177e4 LT |
1711 | goto out; |
1712 | } | |
1713 | ||
1714 | ||
1715 | int security_set_bools(int len, int *values) | |
1716 | { | |
1717 | int i, rc = 0; | |
1718 | int lenp, seqno = 0; | |
1719 | struct cond_node *cur; | |
1720 | ||
1721 | POLICY_WRLOCK; | |
1722 | ||
1723 | lenp = policydb.p_bools.nprim; | |
1724 | if (len != lenp) { | |
1725 | rc = -EFAULT; | |
1726 | goto out; | |
1727 | } | |
1728 | ||
1729 | printk(KERN_INFO "security: committed booleans { "); | |
1730 | for (i = 0; i < len; i++) { | |
1731 | if (values[i]) { | |
1732 | policydb.bool_val_to_struct[i]->state = 1; | |
1733 | } else { | |
1734 | policydb.bool_val_to_struct[i]->state = 0; | |
1735 | } | |
1736 | if (i != 0) | |
1737 | printk(", "); | |
1738 | printk("%s:%d", policydb.p_bool_val_to_name[i], | |
1739 | policydb.bool_val_to_struct[i]->state); | |
1740 | } | |
1741 | printk(" }\n"); | |
1742 | ||
1743 | for (cur = policydb.cond_list; cur != NULL; cur = cur->next) { | |
1744 | rc = evaluate_cond_node(&policydb, cur); | |
1745 | if (rc) | |
1746 | goto out; | |
1747 | } | |
1748 | ||
1749 | seqno = ++latest_granting; | |
1750 | ||
1751 | out: | |
1752 | POLICY_WRUNLOCK; | |
1753 | if (!rc) { | |
1754 | avc_ss_reset(seqno); | |
1755 | selnl_notify_policyload(seqno); | |
1756 | } | |
1757 | return rc; | |
1758 | } | |
1759 | ||
1760 | int security_get_bool_value(int bool) | |
1761 | { | |
1762 | int rc = 0; | |
1763 | int len; | |
1764 | ||
1765 | POLICY_RDLOCK; | |
1766 | ||
1767 | len = policydb.p_bools.nprim; | |
1768 | if (bool >= len) { | |
1769 | rc = -EFAULT; | |
1770 | goto out; | |
1771 | } | |
1772 | ||
1773 | rc = policydb.bool_val_to_struct[bool]->state; | |
1774 | out: | |
1775 | POLICY_RDUNLOCK; | |
1776 | return rc; | |
1777 | } |