blob: 2d6748741a26e4f08e28872d79d846d06e07c6c7 [file] [log] [blame]
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +09001/*
2 * security/tomoyo/domain.c
3 *
4 * Implementation of the Domain-Based Mandatory Access Control.
5 *
6 * Copyright (C) 2005-2009 NTT DATA CORPORATION
7 *
Tetsuo Handa39826a12009-04-08 22:31:28 +09008 * Version: 2.2.0 2009/04/01
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +09009 *
10 */
11
12#include "common.h"
13#include "tomoyo.h"
14#include "realpath.h"
15#include <linux/binfmts.h>
16
17/* Variables definitions.*/
18
19/* The initial domain. */
20struct tomoyo_domain_info tomoyo_kernel_domain;
21
22/* The list for "struct tomoyo_domain_info". */
23LIST_HEAD(tomoyo_domain_list);
24DECLARE_RWSEM(tomoyo_domain_list_lock);
25
26/* Structure for "initialize_domain" and "no_initialize_domain" keyword. */
27struct tomoyo_domain_initializer_entry {
28 struct list_head list;
29 const struct tomoyo_path_info *domainname; /* This may be NULL */
30 const struct tomoyo_path_info *program;
31 bool is_deleted;
32 bool is_not; /* True if this entry is "no_initialize_domain". */
33 /* True if the domainname is tomoyo_get_last_name(). */
34 bool is_last_name;
35};
36
37/* Structure for "keep_domain" and "no_keep_domain" keyword. */
38struct tomoyo_domain_keeper_entry {
39 struct list_head list;
40 const struct tomoyo_path_info *domainname;
41 const struct tomoyo_path_info *program; /* This may be NULL */
42 bool is_deleted;
43 bool is_not; /* True if this entry is "no_keep_domain". */
44 /* True if the domainname is tomoyo_get_last_name(). */
45 bool is_last_name;
46};
47
48/* Structure for "alias" keyword. */
49struct tomoyo_alias_entry {
50 struct list_head list;
51 const struct tomoyo_path_info *original_name;
52 const struct tomoyo_path_info *aliased_name;
53 bool is_deleted;
54};
55
56/**
57 * tomoyo_set_domain_flag - Set or clear domain's attribute flags.
58 *
59 * @domain: Pointer to "struct tomoyo_domain_info".
60 * @is_delete: True if it is a delete request.
61 * @flags: Flags to set or clear.
62 *
63 * Returns nothing.
64 */
65void tomoyo_set_domain_flag(struct tomoyo_domain_info *domain,
66 const bool is_delete, const u8 flags)
67{
68 /* We need to serialize because this is bitfield operation. */
69 static DEFINE_SPINLOCK(lock);
70 /***** CRITICAL SECTION START *****/
71 spin_lock(&lock);
72 if (!is_delete)
73 domain->flags |= flags;
74 else
75 domain->flags &= ~flags;
76 spin_unlock(&lock);
77 /***** CRITICAL SECTION END *****/
78}
79
80/**
81 * tomoyo_get_last_name - Get last component of a domainname.
82 *
83 * @domain: Pointer to "struct tomoyo_domain_info".
84 *
85 * Returns the last component of the domainname.
86 */
87const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain)
88{
89 const char *cp0 = domain->domainname->name;
90 const char *cp1 = strrchr(cp0, ' ');
91
92 if (cp1)
93 return cp1 + 1;
94 return cp0;
95}
96
97/* The list for "struct tomoyo_domain_initializer_entry". */
98static LIST_HEAD(tomoyo_domain_initializer_list);
99static DECLARE_RWSEM(tomoyo_domain_initializer_list_lock);
100
101/**
102 * tomoyo_update_domain_initializer_entry - Update "struct tomoyo_domain_initializer_entry" list.
103 *
104 * @domainname: The name of domain. May be NULL.
105 * @program: The name of program.
106 * @is_not: True if it is "no_initialize_domain" entry.
107 * @is_delete: True if it is a delete request.
108 *
109 * Returns 0 on success, negative value otherwise.
110 */
111static int tomoyo_update_domain_initializer_entry(const char *domainname,
112 const char *program,
113 const bool is_not,
114 const bool is_delete)
115{
116 struct tomoyo_domain_initializer_entry *new_entry;
117 struct tomoyo_domain_initializer_entry *ptr;
118 const struct tomoyo_path_info *saved_program;
119 const struct tomoyo_path_info *saved_domainname = NULL;
120 int error = -ENOMEM;
121 bool is_last_name = false;
122
123 if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__))
124 return -EINVAL; /* No patterns allowed. */
125 if (domainname) {
126 if (!tomoyo_is_domain_def(domainname) &&
127 tomoyo_is_correct_path(domainname, 1, -1, -1, __func__))
128 is_last_name = true;
129 else if (!tomoyo_is_correct_domain(domainname, __func__))
130 return -EINVAL;
131 saved_domainname = tomoyo_save_name(domainname);
132 if (!saved_domainname)
133 return -ENOMEM;
134 }
135 saved_program = tomoyo_save_name(program);
136 if (!saved_program)
137 return -ENOMEM;
138 /***** EXCLUSIVE SECTION START *****/
139 down_write(&tomoyo_domain_initializer_list_lock);
140 list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) {
141 if (ptr->is_not != is_not ||
142 ptr->domainname != saved_domainname ||
143 ptr->program != saved_program)
144 continue;
145 ptr->is_deleted = is_delete;
146 error = 0;
147 goto out;
148 }
149 if (is_delete) {
150 error = -ENOENT;
151 goto out;
152 }
153 new_entry = tomoyo_alloc_element(sizeof(*new_entry));
154 if (!new_entry)
155 goto out;
156 new_entry->domainname = saved_domainname;
157 new_entry->program = saved_program;
158 new_entry->is_not = is_not;
159 new_entry->is_last_name = is_last_name;
160 list_add_tail(&new_entry->list, &tomoyo_domain_initializer_list);
161 error = 0;
162 out:
163 up_write(&tomoyo_domain_initializer_list_lock);
164 /***** EXCLUSIVE SECTION END *****/
165 return error;
166}
167
168/**
169 * tomoyo_read_domain_initializer_policy - Read "struct tomoyo_domain_initializer_entry" list.
170 *
171 * @head: Pointer to "struct tomoyo_io_buffer".
172 *
173 * Returns true on success, false otherwise.
174 */
175bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head)
176{
177 struct list_head *pos;
178 bool done = true;
179
180 down_read(&tomoyo_domain_initializer_list_lock);
181 list_for_each_cookie(pos, head->read_var2,
182 &tomoyo_domain_initializer_list) {
183 const char *no;
184 const char *from = "";
185 const char *domain = "";
186 struct tomoyo_domain_initializer_entry *ptr;
187 ptr = list_entry(pos, struct tomoyo_domain_initializer_entry,
188 list);
189 if (ptr->is_deleted)
190 continue;
191 no = ptr->is_not ? "no_" : "";
192 if (ptr->domainname) {
193 from = " from ";
194 domain = ptr->domainname->name;
195 }
196 if (!tomoyo_io_printf(head,
197 "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN
198 "%s%s%s\n", no, ptr->program->name, from,
199 domain)) {
200 done = false;
201 break;
202 }
203 }
204 up_read(&tomoyo_domain_initializer_list_lock);
205 return done;
206}
207
208/**
209 * tomoyo_write_domain_initializer_policy - Write "struct tomoyo_domain_initializer_entry" list.
210 *
211 * @data: String to parse.
212 * @is_not: True if it is "no_initialize_domain" entry.
213 * @is_delete: True if it is a delete request.
214 *
215 * Returns 0 on success, negative value otherwise.
216 */
217int tomoyo_write_domain_initializer_policy(char *data, const bool is_not,
218 const bool is_delete)
219{
220 char *cp = strstr(data, " from ");
221
222 if (cp) {
223 *cp = '\0';
224 return tomoyo_update_domain_initializer_entry(cp + 6, data,
225 is_not,
226 is_delete);
227 }
228 return tomoyo_update_domain_initializer_entry(NULL, data, is_not,
229 is_delete);
230}
231
232/**
233 * tomoyo_is_domain_initializer - Check whether the given program causes domainname reinitialization.
234 *
235 * @domainname: The name of domain.
236 * @program: The name of program.
237 * @last_name: The last component of @domainname.
238 *
239 * Returns true if executing @program reinitializes domain transition,
240 * false otherwise.
241 */
242static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info *
243 domainname,
244 const struct tomoyo_path_info *program,
245 const struct tomoyo_path_info *
246 last_name)
247{
248 struct tomoyo_domain_initializer_entry *ptr;
249 bool flag = false;
250
251 down_read(&tomoyo_domain_initializer_list_lock);
252 list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) {
253 if (ptr->is_deleted)
254 continue;
255 if (ptr->domainname) {
256 if (!ptr->is_last_name) {
257 if (ptr->domainname != domainname)
258 continue;
259 } else {
260 if (tomoyo_pathcmp(ptr->domainname, last_name))
261 continue;
262 }
263 }
264 if (tomoyo_pathcmp(ptr->program, program))
265 continue;
266 if (ptr->is_not) {
267 flag = false;
268 break;
269 }
270 flag = true;
271 }
272 up_read(&tomoyo_domain_initializer_list_lock);
273 return flag;
274}
275
276/* The list for "struct tomoyo_domain_keeper_entry". */
277static LIST_HEAD(tomoyo_domain_keeper_list);
278static DECLARE_RWSEM(tomoyo_domain_keeper_list_lock);
279
280/**
281 * tomoyo_update_domain_keeper_entry - Update "struct tomoyo_domain_keeper_entry" list.
282 *
283 * @domainname: The name of domain.
284 * @program: The name of program. May be NULL.
285 * @is_not: True if it is "no_keep_domain" entry.
286 * @is_delete: True if it is a delete request.
287 *
288 * Returns 0 on success, negative value otherwise.
289 */
290static int tomoyo_update_domain_keeper_entry(const char *domainname,
291 const char *program,
292 const bool is_not,
293 const bool is_delete)
294{
295 struct tomoyo_domain_keeper_entry *new_entry;
296 struct tomoyo_domain_keeper_entry *ptr;
297 const struct tomoyo_path_info *saved_domainname;
298 const struct tomoyo_path_info *saved_program = NULL;
299 static DEFINE_MUTEX(lock);
300 int error = -ENOMEM;
301 bool is_last_name = false;
302
303 if (!tomoyo_is_domain_def(domainname) &&
304 tomoyo_is_correct_path(domainname, 1, -1, -1, __func__))
305 is_last_name = true;
306 else if (!tomoyo_is_correct_domain(domainname, __func__))
307 return -EINVAL;
308 if (program) {
309 if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__))
310 return -EINVAL;
311 saved_program = tomoyo_save_name(program);
312 if (!saved_program)
313 return -ENOMEM;
314 }
315 saved_domainname = tomoyo_save_name(domainname);
316 if (!saved_domainname)
317 return -ENOMEM;
318 /***** EXCLUSIVE SECTION START *****/
319 down_write(&tomoyo_domain_keeper_list_lock);
320 list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
321 if (ptr->is_not != is_not ||
322 ptr->domainname != saved_domainname ||
323 ptr->program != saved_program)
324 continue;
325 ptr->is_deleted = is_delete;
326 error = 0;
327 goto out;
328 }
329 if (is_delete) {
330 error = -ENOENT;
331 goto out;
332 }
333 new_entry = tomoyo_alloc_element(sizeof(*new_entry));
334 if (!new_entry)
335 goto out;
336 new_entry->domainname = saved_domainname;
337 new_entry->program = saved_program;
338 new_entry->is_not = is_not;
339 new_entry->is_last_name = is_last_name;
340 list_add_tail(&new_entry->list, &tomoyo_domain_keeper_list);
341 error = 0;
342 out:
343 up_write(&tomoyo_domain_keeper_list_lock);
344 /***** EXCLUSIVE SECTION END *****/
345 return error;
346}
347
348/**
349 * tomoyo_write_domain_keeper_policy - Write "struct tomoyo_domain_keeper_entry" list.
350 *
351 * @data: String to parse.
352 * @is_not: True if it is "no_keep_domain" entry.
353 * @is_delete: True if it is a delete request.
354 *
355 */
356int tomoyo_write_domain_keeper_policy(char *data, const bool is_not,
357 const bool is_delete)
358{
359 char *cp = strstr(data, " from ");
360
361 if (cp) {
362 *cp = '\0';
363 return tomoyo_update_domain_keeper_entry(cp + 6, data, is_not,
364 is_delete);
365 }
366 return tomoyo_update_domain_keeper_entry(data, NULL, is_not, is_delete);
367}
368
369/**
370 * tomoyo_read_domain_keeper_policy - Read "struct tomoyo_domain_keeper_entry" list.
371 *
372 * @head: Pointer to "struct tomoyo_io_buffer".
373 *
374 * Returns true on success, false otherwise.
375 */
376bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head)
377{
378 struct list_head *pos;
Tetsuo Handa33043cb2009-02-13 16:00:58 +0900379 bool done = true;
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +0900380
381 down_read(&tomoyo_domain_keeper_list_lock);
382 list_for_each_cookie(pos, head->read_var2,
383 &tomoyo_domain_keeper_list) {
384 struct tomoyo_domain_keeper_entry *ptr;
385 const char *no;
386 const char *from = "";
387 const char *program = "";
388
389 ptr = list_entry(pos, struct tomoyo_domain_keeper_entry, list);
390 if (ptr->is_deleted)
391 continue;
392 no = ptr->is_not ? "no_" : "";
393 if (ptr->program) {
394 from = " from ";
395 program = ptr->program->name;
396 }
397 if (!tomoyo_io_printf(head,
398 "%s" TOMOYO_KEYWORD_KEEP_DOMAIN
399 "%s%s%s\n", no, program, from,
400 ptr->domainname->name)) {
401 done = false;
402 break;
403 }
404 }
405 up_read(&tomoyo_domain_keeper_list_lock);
406 return done;
407}
408
409/**
410 * tomoyo_is_domain_keeper - Check whether the given program causes domain transition suppression.
411 *
412 * @domainname: The name of domain.
413 * @program: The name of program.
414 * @last_name: The last component of @domainname.
415 *
416 * Returns true if executing @program supresses domain transition,
417 * false otherwise.
418 */
419static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname,
420 const struct tomoyo_path_info *program,
421 const struct tomoyo_path_info *last_name)
422{
423 struct tomoyo_domain_keeper_entry *ptr;
424 bool flag = false;
425
426 down_read(&tomoyo_domain_keeper_list_lock);
427 list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
428 if (ptr->is_deleted)
429 continue;
430 if (!ptr->is_last_name) {
431 if (ptr->domainname != domainname)
432 continue;
433 } else {
434 if (tomoyo_pathcmp(ptr->domainname, last_name))
435 continue;
436 }
437 if (ptr->program && tomoyo_pathcmp(ptr->program, program))
438 continue;
439 if (ptr->is_not) {
440 flag = false;
441 break;
442 }
443 flag = true;
444 }
445 up_read(&tomoyo_domain_keeper_list_lock);
446 return flag;
447}
448
449/* The list for "struct tomoyo_alias_entry". */
450static LIST_HEAD(tomoyo_alias_list);
451static DECLARE_RWSEM(tomoyo_alias_list_lock);
452
453/**
454 * tomoyo_update_alias_entry - Update "struct tomoyo_alias_entry" list.
455 *
456 * @original_name: The original program's real name.
457 * @aliased_name: The symbolic program's symbolic link's name.
458 * @is_delete: True if it is a delete request.
459 *
460 * Returns 0 on success, negative value otherwise.
461 */
462static int tomoyo_update_alias_entry(const char *original_name,
463 const char *aliased_name,
464 const bool is_delete)
465{
466 struct tomoyo_alias_entry *new_entry;
467 struct tomoyo_alias_entry *ptr;
468 const struct tomoyo_path_info *saved_original_name;
469 const struct tomoyo_path_info *saved_aliased_name;
470 int error = -ENOMEM;
471
472 if (!tomoyo_is_correct_path(original_name, 1, -1, -1, __func__) ||
473 !tomoyo_is_correct_path(aliased_name, 1, -1, -1, __func__))
474 return -EINVAL; /* No patterns allowed. */
475 saved_original_name = tomoyo_save_name(original_name);
476 saved_aliased_name = tomoyo_save_name(aliased_name);
477 if (!saved_original_name || !saved_aliased_name)
478 return -ENOMEM;
479 /***** EXCLUSIVE SECTION START *****/
480 down_write(&tomoyo_alias_list_lock);
481 list_for_each_entry(ptr, &tomoyo_alias_list, list) {
482 if (ptr->original_name != saved_original_name ||
483 ptr->aliased_name != saved_aliased_name)
484 continue;
485 ptr->is_deleted = is_delete;
486 error = 0;
487 goto out;
488 }
489 if (is_delete) {
490 error = -ENOENT;
491 goto out;
492 }
493 new_entry = tomoyo_alloc_element(sizeof(*new_entry));
494 if (!new_entry)
495 goto out;
496 new_entry->original_name = saved_original_name;
497 new_entry->aliased_name = saved_aliased_name;
498 list_add_tail(&new_entry->list, &tomoyo_alias_list);
499 error = 0;
500 out:
501 up_write(&tomoyo_alias_list_lock);
502 /***** EXCLUSIVE SECTION END *****/
503 return error;
504}
505
506/**
507 * tomoyo_read_alias_policy - Read "struct tomoyo_alias_entry" list.
508 *
509 * @head: Pointer to "struct tomoyo_io_buffer".
510 *
511 * Returns true on success, false otherwise.
512 */
513bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head)
514{
515 struct list_head *pos;
516 bool done = true;
517
518 down_read(&tomoyo_alias_list_lock);
519 list_for_each_cookie(pos, head->read_var2, &tomoyo_alias_list) {
520 struct tomoyo_alias_entry *ptr;
521
522 ptr = list_entry(pos, struct tomoyo_alias_entry, list);
523 if (ptr->is_deleted)
524 continue;
525 if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n",
526 ptr->original_name->name,
527 ptr->aliased_name->name)) {
528 done = false;
529 break;
530 }
531 }
532 up_read(&tomoyo_alias_list_lock);
533 return done;
534}
535
536/**
537 * tomoyo_write_alias_policy - Write "struct tomoyo_alias_entry" list.
538 *
539 * @data: String to parse.
540 * @is_delete: True if it is a delete request.
541 *
542 * Returns 0 on success, negative value otherwise.
543 */
544int tomoyo_write_alias_policy(char *data, const bool is_delete)
545{
546 char *cp = strchr(data, ' ');
547
548 if (!cp)
549 return -EINVAL;
550 *cp++ = '\0';
551 return tomoyo_update_alias_entry(data, cp, is_delete);
552}
553
Tetsuo Handaa0558fc2009-04-06 20:49:14 +0900554/* Domain create/delete handler. */
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +0900555
556/**
557 * tomoyo_delete_domain - Delete a domain.
558 *
559 * @domainname: The name of domain.
560 *
561 * Returns 0.
562 */
563int tomoyo_delete_domain(char *domainname)
564{
565 struct tomoyo_domain_info *domain;
566 struct tomoyo_path_info name;
567
568 name.name = domainname;
569 tomoyo_fill_path_info(&name);
570 /***** EXCLUSIVE SECTION START *****/
571 down_write(&tomoyo_domain_list_lock);
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +0900572 /* Is there an active domain? */
573 list_for_each_entry(domain, &tomoyo_domain_list, list) {
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +0900574 /* Never delete tomoyo_kernel_domain */
575 if (domain == &tomoyo_kernel_domain)
576 continue;
577 if (domain->is_deleted ||
578 tomoyo_pathcmp(domain->domainname, &name))
579 continue;
Tetsuo Handaa0558fc2009-04-06 20:49:14 +0900580 domain->is_deleted = true;
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +0900581 break;
582 }
583 up_write(&tomoyo_domain_list_lock);
584 /***** EXCLUSIVE SECTION END *****/
585 return 0;
586}
587
588/**
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +0900589 * tomoyo_find_or_assign_new_domain - Create a domain.
590 *
591 * @domainname: The name of domain.
592 * @profile: Profile number to assign if the domain was newly created.
593 *
594 * Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise.
595 */
596struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
597 domainname,
598 const u8 profile)
599{
600 struct tomoyo_domain_info *domain = NULL;
601 const struct tomoyo_path_info *saved_domainname;
602
603 /***** EXCLUSIVE SECTION START *****/
604 down_write(&tomoyo_domain_list_lock);
605 domain = tomoyo_find_domain(domainname);
606 if (domain)
607 goto out;
608 if (!tomoyo_is_correct_domain(domainname, __func__))
609 goto out;
610 saved_domainname = tomoyo_save_name(domainname);
611 if (!saved_domainname)
612 goto out;
613 /* Can I reuse memory of deleted domain? */
614 list_for_each_entry(domain, &tomoyo_domain_list, list) {
615 struct task_struct *p;
616 struct tomoyo_acl_info *ptr;
617 bool flag;
618 if (!domain->is_deleted ||
619 domain->domainname != saved_domainname)
620 continue;
621 flag = false;
622 /***** CRITICAL SECTION START *****/
623 read_lock(&tasklist_lock);
624 for_each_process(p) {
625 if (tomoyo_real_domain(p) != domain)
626 continue;
627 flag = true;
628 break;
629 }
630 read_unlock(&tasklist_lock);
631 /***** CRITICAL SECTION END *****/
632 if (flag)
633 continue;
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +0900634 list_for_each_entry(ptr, &domain->acl_info_list, list) {
635 ptr->type |= TOMOYO_ACL_DELETED;
636 }
637 tomoyo_set_domain_flag(domain, true, domain->flags);
638 domain->profile = profile;
639 domain->quota_warned = false;
640 mb(); /* Avoid out-of-order execution. */
Tetsuo Handaa0558fc2009-04-06 20:49:14 +0900641 domain->is_deleted = false;
Kentaro Takeda26a2a1c2009-02-05 17:18:15 +0900642 goto out;
643 }
644 /* No memory reusable. Create using new memory. */
645 domain = tomoyo_alloc_element(sizeof(*domain));
646 if (domain) {
647 INIT_LIST_HEAD(&domain->acl_info_list);
648 domain->domainname = saved_domainname;
649 domain->profile = profile;
650 list_add_tail(&domain->list, &tomoyo_domain_list);
651 }
652 out:
653 up_write(&tomoyo_domain_list_lock);
654 /***** EXCLUSIVE SECTION END *****/
655 return domain;
656}
657
658/**
659 * tomoyo_find_next_domain - Find a domain.
660 *
661 * @bprm: Pointer to "struct linux_binprm".
662 * @next_domain: Pointer to pointer to "struct tomoyo_domain_info".
663 *
664 * Returns 0 on success, negative value otherwise.
665 */
666int tomoyo_find_next_domain(struct linux_binprm *bprm,
667 struct tomoyo_domain_info **next_domain)
668{
669 /*
670 * This function assumes that the size of buffer returned by
671 * tomoyo_realpath() = TOMOYO_MAX_PATHNAME_LEN.
672 */
673 struct tomoyo_page_buffer *tmp = tomoyo_alloc(sizeof(*tmp));
674 struct tomoyo_domain_info *old_domain = tomoyo_domain();
675 struct tomoyo_domain_info *domain = NULL;
676 const char *old_domain_name = old_domain->domainname->name;
677 const char *original_name = bprm->filename;
678 char *new_domain_name = NULL;
679 char *real_program_name = NULL;
680 char *symlink_program_name = NULL;
681 const u8 mode = tomoyo_check_flags(old_domain, TOMOYO_MAC_FOR_FILE);
682 const bool is_enforce = (mode == 3);
683 int retval = -ENOMEM;
684 struct tomoyo_path_info r; /* real name */
685 struct tomoyo_path_info s; /* symlink name */
686 struct tomoyo_path_info l; /* last name */
687 static bool initialized;
688
689 if (!tmp)
690 goto out;
691
692 if (!initialized) {
693 /*
694 * Built-in initializers. This is needed because policies are
695 * not loaded until starting /sbin/init.
696 */
697 tomoyo_update_domain_initializer_entry(NULL, "/sbin/hotplug",
698 false, false);
699 tomoyo_update_domain_initializer_entry(NULL, "/sbin/modprobe",
700 false, false);
701 initialized = true;
702 }
703
704 /* Get tomoyo_realpath of program. */
705 retval = -ENOENT;
706 /* I hope tomoyo_realpath() won't fail with -ENOMEM. */
707 real_program_name = tomoyo_realpath(original_name);
708 if (!real_program_name)
709 goto out;
710 /* Get tomoyo_realpath of symbolic link. */
711 symlink_program_name = tomoyo_realpath_nofollow(original_name);
712 if (!symlink_program_name)
713 goto out;
714
715 r.name = real_program_name;
716 tomoyo_fill_path_info(&r);
717 s.name = symlink_program_name;
718 tomoyo_fill_path_info(&s);
719 l.name = tomoyo_get_last_name(old_domain);
720 tomoyo_fill_path_info(&l);
721
722 /* Check 'alias' directive. */
723 if (tomoyo_pathcmp(&r, &s)) {
724 struct tomoyo_alias_entry *ptr;
725 /* Is this program allowed to be called via symbolic links? */
726 down_read(&tomoyo_alias_list_lock);
727 list_for_each_entry(ptr, &tomoyo_alias_list, list) {
728 if (ptr->is_deleted ||
729 tomoyo_pathcmp(&r, ptr->original_name) ||
730 tomoyo_pathcmp(&s, ptr->aliased_name))
731 continue;
732 memset(real_program_name, 0, TOMOYO_MAX_PATHNAME_LEN);
733 strncpy(real_program_name, ptr->aliased_name->name,
734 TOMOYO_MAX_PATHNAME_LEN - 1);
735 tomoyo_fill_path_info(&r);
736 break;
737 }
738 up_read(&tomoyo_alias_list_lock);
739 }
740
741 /* Check execute permission. */
742 retval = tomoyo_check_exec_perm(old_domain, &r, tmp);
743 if (retval < 0)
744 goto out;
745
746 new_domain_name = tmp->buffer;
747 if (tomoyo_is_domain_initializer(old_domain->domainname, &r, &l)) {
748 /* Transit to the child of tomoyo_kernel_domain domain. */
749 snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1,
750 TOMOYO_ROOT_NAME " " "%s", real_program_name);
751 } else if (old_domain == &tomoyo_kernel_domain &&
752 !tomoyo_policy_loaded) {
753 /*
754 * Needn't to transit from kernel domain before starting
755 * /sbin/init. But transit from kernel domain if executing
756 * initializers because they might start before /sbin/init.
757 */
758 domain = old_domain;
759 } else if (tomoyo_is_domain_keeper(old_domain->domainname, &r, &l)) {
760 /* Keep current domain. */
761 domain = old_domain;
762 } else {
763 /* Normal domain transition. */
764 snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1,
765 "%s %s", old_domain_name, real_program_name);
766 }
767 if (domain || strlen(new_domain_name) >= TOMOYO_MAX_PATHNAME_LEN)
768 goto done;
769 down_read(&tomoyo_domain_list_lock);
770 domain = tomoyo_find_domain(new_domain_name);
771 up_read(&tomoyo_domain_list_lock);
772 if (domain)
773 goto done;
774 if (is_enforce)
775 goto done;
776 domain = tomoyo_find_or_assign_new_domain(new_domain_name,
777 old_domain->profile);
778 done:
779 if (domain)
780 goto out;
781 printk(KERN_WARNING "TOMOYO-ERROR: Domain '%s' not defined.\n",
782 new_domain_name);
783 if (is_enforce)
784 retval = -EPERM;
785 else
786 tomoyo_set_domain_flag(old_domain, false,
787 TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED);
788 out:
789 tomoyo_free(real_program_name);
790 tomoyo_free(symlink_program_name);
791 *next_domain = domain ? domain : old_domain;
792 tomoyo_free(tmp);
793 return retval;
794}