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26a2a1c9 KT |
1 | /* |
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 | * | |
39826a1e | 8 | * Version: 2.2.0 2009/04/01 |
26a2a1c9 KT |
9 | * |
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. */ | |
20 | struct tomoyo_domain_info tomoyo_kernel_domain; | |
21 | ||
c3fa109a TH |
22 | /* |
23 | * tomoyo_domain_list is used for holding list of domains. | |
24 | * The ->acl_info_list of "struct tomoyo_domain_info" is used for holding | |
25 | * permissions (e.g. "allow_read /lib/libc-2.5.so") given to each domain. | |
26 | * | |
27 | * An entry is added by | |
28 | * | |
29 | * # ( echo "<kernel>"; echo "allow_execute /sbin/init" ) > \ | |
30 | * /sys/kernel/security/tomoyo/domain_policy | |
31 | * | |
32 | * and is deleted by | |
33 | * | |
34 | * # ( echo "<kernel>"; echo "delete allow_execute /sbin/init" ) > \ | |
35 | * /sys/kernel/security/tomoyo/domain_policy | |
36 | * | |
37 | * and all entries are retrieved by | |
38 | * | |
39 | * # cat /sys/kernel/security/tomoyo/domain_policy | |
40 | * | |
41 | * A domain is added by | |
42 | * | |
43 | * # echo "<kernel>" > /sys/kernel/security/tomoyo/domain_policy | |
44 | * | |
45 | * and is deleted by | |
46 | * | |
47 | * # echo "delete <kernel>" > /sys/kernel/security/tomoyo/domain_policy | |
48 | * | |
49 | * and all domains are retrieved by | |
50 | * | |
51 | * # grep '^<kernel>' /sys/kernel/security/tomoyo/domain_policy | |
52 | * | |
53 | * Normally, a domainname is monotonically getting longer because a domainname | |
54 | * which the process will belong to if an execve() operation succeeds is | |
55 | * defined as a concatenation of "current domainname" + "pathname passed to | |
56 | * execve()". | |
57 | * See tomoyo_domain_initializer_list and tomoyo_domain_keeper_list for | |
58 | * exceptions. | |
59 | */ | |
26a2a1c9 KT |
60 | LIST_HEAD(tomoyo_domain_list); |
61 | DECLARE_RWSEM(tomoyo_domain_list_lock); | |
62 | ||
c3fa109a TH |
63 | /* |
64 | * tomoyo_domain_initializer_entry is a structure which is used for holding | |
65 | * "initialize_domain" and "no_initialize_domain" entries. | |
66 | * It has following fields. | |
67 | * | |
68 | * (1) "list" which is linked to tomoyo_domain_initializer_list . | |
69 | * (2) "domainname" which is "a domainname" or "the last component of a | |
70 | * domainname". This field is NULL if "from" clause is not specified. | |
71 | * (3) "program" which is a program's pathname. | |
72 | * (4) "is_deleted" is a bool which is true if marked as deleted, false | |
73 | * otherwise. | |
74 | * (5) "is_not" is a bool which is true if "no_initialize_domain", false | |
75 | * otherwise. | |
76 | * (6) "is_last_name" is a bool which is true if "domainname" is "the last | |
77 | * component of a domainname", false otherwise. | |
78 | */ | |
26a2a1c9 KT |
79 | struct tomoyo_domain_initializer_entry { |
80 | struct list_head list; | |
81 | const struct tomoyo_path_info *domainname; /* This may be NULL */ | |
82 | const struct tomoyo_path_info *program; | |
83 | bool is_deleted; | |
84 | bool is_not; /* True if this entry is "no_initialize_domain". */ | |
85 | /* True if the domainname is tomoyo_get_last_name(). */ | |
86 | bool is_last_name; | |
87 | }; | |
88 | ||
c3fa109a TH |
89 | /* |
90 | * tomoyo_domain_keeper_entry is a structure which is used for holding | |
91 | * "keep_domain" and "no_keep_domain" entries. | |
92 | * It has following fields. | |
93 | * | |
94 | * (1) "list" which is linked to tomoyo_domain_keeper_list . | |
95 | * (2) "domainname" which is "a domainname" or "the last component of a | |
96 | * domainname". | |
97 | * (3) "program" which is a program's pathname. | |
98 | * This field is NULL if "from" clause is not specified. | |
99 | * (4) "is_deleted" is a bool which is true if marked as deleted, false | |
100 | * otherwise. | |
101 | * (5) "is_not" is a bool which is true if "no_initialize_domain", false | |
102 | * otherwise. | |
103 | * (6) "is_last_name" is a bool which is true if "domainname" is "the last | |
104 | * component of a domainname", false otherwise. | |
105 | */ | |
26a2a1c9 KT |
106 | struct tomoyo_domain_keeper_entry { |
107 | struct list_head list; | |
108 | const struct tomoyo_path_info *domainname; | |
109 | const struct tomoyo_path_info *program; /* This may be NULL */ | |
110 | bool is_deleted; | |
111 | bool is_not; /* True if this entry is "no_keep_domain". */ | |
112 | /* True if the domainname is tomoyo_get_last_name(). */ | |
113 | bool is_last_name; | |
114 | }; | |
115 | ||
c3fa109a TH |
116 | /* |
117 | * tomoyo_alias_entry is a structure which is used for holding "alias" entries. | |
118 | * It has following fields. | |
119 | * | |
120 | * (1) "list" which is linked to tomoyo_alias_list . | |
121 | * (2) "original_name" which is a dereferenced pathname. | |
122 | * (3) "aliased_name" which is a symlink's pathname. | |
123 | * (4) "is_deleted" is a bool which is true if marked as deleted, false | |
124 | * otherwise. | |
125 | */ | |
26a2a1c9 KT |
126 | struct tomoyo_alias_entry { |
127 | struct list_head list; | |
128 | const struct tomoyo_path_info *original_name; | |
129 | const struct tomoyo_path_info *aliased_name; | |
130 | bool is_deleted; | |
131 | }; | |
132 | ||
133 | /** | |
134 | * tomoyo_set_domain_flag - Set or clear domain's attribute flags. | |
135 | * | |
136 | * @domain: Pointer to "struct tomoyo_domain_info". | |
137 | * @is_delete: True if it is a delete request. | |
138 | * @flags: Flags to set or clear. | |
139 | * | |
140 | * Returns nothing. | |
141 | */ | |
142 | void tomoyo_set_domain_flag(struct tomoyo_domain_info *domain, | |
143 | const bool is_delete, const u8 flags) | |
144 | { | |
145 | /* We need to serialize because this is bitfield operation. */ | |
146 | static DEFINE_SPINLOCK(lock); | |
26a2a1c9 KT |
147 | spin_lock(&lock); |
148 | if (!is_delete) | |
149 | domain->flags |= flags; | |
150 | else | |
151 | domain->flags &= ~flags; | |
152 | spin_unlock(&lock); | |
26a2a1c9 KT |
153 | } |
154 | ||
155 | /** | |
156 | * tomoyo_get_last_name - Get last component of a domainname. | |
157 | * | |
158 | * @domain: Pointer to "struct tomoyo_domain_info". | |
159 | * | |
160 | * Returns the last component of the domainname. | |
161 | */ | |
162 | const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain) | |
163 | { | |
164 | const char *cp0 = domain->domainname->name; | |
165 | const char *cp1 = strrchr(cp0, ' '); | |
166 | ||
167 | if (cp1) | |
168 | return cp1 + 1; | |
169 | return cp0; | |
170 | } | |
171 | ||
c3fa109a TH |
172 | /* |
173 | * tomoyo_domain_initializer_list is used for holding list of programs which | |
174 | * triggers reinitialization of domainname. Normally, a domainname is | |
175 | * monotonically getting longer. But sometimes, we restart daemon programs. | |
176 | * It would be convenient for us that "a daemon started upon system boot" and | |
177 | * "the daemon restarted from console" belong to the same domain. Thus, TOMOYO | |
178 | * provides a way to shorten domainnames. | |
179 | * | |
180 | * An entry is added by | |
181 | * | |
182 | * # echo 'initialize_domain /usr/sbin/httpd' > \ | |
183 | * /sys/kernel/security/tomoyo/exception_policy | |
184 | * | |
185 | * and is deleted by | |
186 | * | |
187 | * # echo 'delete initialize_domain /usr/sbin/httpd' > \ | |
188 | * /sys/kernel/security/tomoyo/exception_policy | |
189 | * | |
190 | * and all entries are retrieved by | |
191 | * | |
192 | * # grep ^initialize_domain /sys/kernel/security/tomoyo/exception_policy | |
193 | * | |
194 | * In the example above, /usr/sbin/httpd will belong to | |
195 | * "<kernel> /usr/sbin/httpd" domain. | |
196 | * | |
197 | * You may specify a domainname using "from" keyword. | |
198 | * "initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd" | |
199 | * will cause "/usr/sbin/httpd" executed from "<kernel> /etc/rc.d/init.d/httpd" | |
200 | * domain to belong to "<kernel> /usr/sbin/httpd" domain. | |
201 | * | |
202 | * You may add "no_" prefix to "initialize_domain". | |
203 | * "initialize_domain /usr/sbin/httpd" and | |
204 | * "no_initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd" | |
205 | * will cause "/usr/sbin/httpd" to belong to "<kernel> /usr/sbin/httpd" domain | |
206 | * unless executed from "<kernel> /etc/rc.d/init.d/httpd" domain. | |
207 | */ | |
26a2a1c9 KT |
208 | static LIST_HEAD(tomoyo_domain_initializer_list); |
209 | static DECLARE_RWSEM(tomoyo_domain_initializer_list_lock); | |
210 | ||
211 | /** | |
212 | * tomoyo_update_domain_initializer_entry - Update "struct tomoyo_domain_initializer_entry" list. | |
213 | * | |
214 | * @domainname: The name of domain. May be NULL. | |
215 | * @program: The name of program. | |
216 | * @is_not: True if it is "no_initialize_domain" entry. | |
217 | * @is_delete: True if it is a delete request. | |
218 | * | |
219 | * Returns 0 on success, negative value otherwise. | |
220 | */ | |
221 | static int tomoyo_update_domain_initializer_entry(const char *domainname, | |
222 | const char *program, | |
223 | const bool is_not, | |
224 | const bool is_delete) | |
225 | { | |
226 | struct tomoyo_domain_initializer_entry *new_entry; | |
227 | struct tomoyo_domain_initializer_entry *ptr; | |
228 | const struct tomoyo_path_info *saved_program; | |
229 | const struct tomoyo_path_info *saved_domainname = NULL; | |
230 | int error = -ENOMEM; | |
231 | bool is_last_name = false; | |
232 | ||
233 | if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__)) | |
234 | return -EINVAL; /* No patterns allowed. */ | |
235 | if (domainname) { | |
236 | if (!tomoyo_is_domain_def(domainname) && | |
237 | tomoyo_is_correct_path(domainname, 1, -1, -1, __func__)) | |
238 | is_last_name = true; | |
239 | else if (!tomoyo_is_correct_domain(domainname, __func__)) | |
240 | return -EINVAL; | |
241 | saved_domainname = tomoyo_save_name(domainname); | |
242 | if (!saved_domainname) | |
243 | return -ENOMEM; | |
244 | } | |
245 | saved_program = tomoyo_save_name(program); | |
246 | if (!saved_program) | |
247 | return -ENOMEM; | |
26a2a1c9 KT |
248 | down_write(&tomoyo_domain_initializer_list_lock); |
249 | list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) { | |
250 | if (ptr->is_not != is_not || | |
251 | ptr->domainname != saved_domainname || | |
252 | ptr->program != saved_program) | |
253 | continue; | |
254 | ptr->is_deleted = is_delete; | |
255 | error = 0; | |
256 | goto out; | |
257 | } | |
258 | if (is_delete) { | |
259 | error = -ENOENT; | |
260 | goto out; | |
261 | } | |
262 | new_entry = tomoyo_alloc_element(sizeof(*new_entry)); | |
263 | if (!new_entry) | |
264 | goto out; | |
265 | new_entry->domainname = saved_domainname; | |
266 | new_entry->program = saved_program; | |
267 | new_entry->is_not = is_not; | |
268 | new_entry->is_last_name = is_last_name; | |
269 | list_add_tail(&new_entry->list, &tomoyo_domain_initializer_list); | |
270 | error = 0; | |
271 | out: | |
272 | up_write(&tomoyo_domain_initializer_list_lock); | |
26a2a1c9 KT |
273 | return error; |
274 | } | |
275 | ||
276 | /** | |
277 | * tomoyo_read_domain_initializer_policy - Read "struct tomoyo_domain_initializer_entry" list. | |
278 | * | |
279 | * @head: Pointer to "struct tomoyo_io_buffer". | |
280 | * | |
281 | * Returns true on success, false otherwise. | |
282 | */ | |
283 | bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head) | |
284 | { | |
285 | struct list_head *pos; | |
286 | bool done = true; | |
287 | ||
288 | down_read(&tomoyo_domain_initializer_list_lock); | |
289 | list_for_each_cookie(pos, head->read_var2, | |
290 | &tomoyo_domain_initializer_list) { | |
291 | const char *no; | |
292 | const char *from = ""; | |
293 | const char *domain = ""; | |
294 | struct tomoyo_domain_initializer_entry *ptr; | |
295 | ptr = list_entry(pos, struct tomoyo_domain_initializer_entry, | |
296 | list); | |
297 | if (ptr->is_deleted) | |
298 | continue; | |
299 | no = ptr->is_not ? "no_" : ""; | |
300 | if (ptr->domainname) { | |
301 | from = " from "; | |
302 | domain = ptr->domainname->name; | |
303 | } | |
7d2948b1 TH |
304 | done = tomoyo_io_printf(head, |
305 | "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN | |
306 | "%s%s%s\n", no, ptr->program->name, | |
307 | from, domain); | |
308 | if (!done) | |
26a2a1c9 | 309 | break; |
26a2a1c9 KT |
310 | } |
311 | up_read(&tomoyo_domain_initializer_list_lock); | |
312 | return done; | |
313 | } | |
314 | ||
315 | /** | |
316 | * tomoyo_write_domain_initializer_policy - Write "struct tomoyo_domain_initializer_entry" list. | |
317 | * | |
318 | * @data: String to parse. | |
319 | * @is_not: True if it is "no_initialize_domain" entry. | |
320 | * @is_delete: True if it is a delete request. | |
321 | * | |
322 | * Returns 0 on success, negative value otherwise. | |
323 | */ | |
324 | int tomoyo_write_domain_initializer_policy(char *data, const bool is_not, | |
325 | const bool is_delete) | |
326 | { | |
327 | char *cp = strstr(data, " from "); | |
328 | ||
329 | if (cp) { | |
330 | *cp = '\0'; | |
331 | return tomoyo_update_domain_initializer_entry(cp + 6, data, | |
332 | is_not, | |
333 | is_delete); | |
334 | } | |
335 | return tomoyo_update_domain_initializer_entry(NULL, data, is_not, | |
336 | is_delete); | |
337 | } | |
338 | ||
339 | /** | |
340 | * tomoyo_is_domain_initializer - Check whether the given program causes domainname reinitialization. | |
341 | * | |
342 | * @domainname: The name of domain. | |
343 | * @program: The name of program. | |
344 | * @last_name: The last component of @domainname. | |
345 | * | |
346 | * Returns true if executing @program reinitializes domain transition, | |
347 | * false otherwise. | |
348 | */ | |
349 | static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info * | |
350 | domainname, | |
351 | const struct tomoyo_path_info *program, | |
352 | const struct tomoyo_path_info * | |
353 | last_name) | |
354 | { | |
355 | struct tomoyo_domain_initializer_entry *ptr; | |
356 | bool flag = false; | |
357 | ||
358 | down_read(&tomoyo_domain_initializer_list_lock); | |
359 | list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) { | |
360 | if (ptr->is_deleted) | |
361 | continue; | |
362 | if (ptr->domainname) { | |
363 | if (!ptr->is_last_name) { | |
364 | if (ptr->domainname != domainname) | |
365 | continue; | |
366 | } else { | |
367 | if (tomoyo_pathcmp(ptr->domainname, last_name)) | |
368 | continue; | |
369 | } | |
370 | } | |
371 | if (tomoyo_pathcmp(ptr->program, program)) | |
372 | continue; | |
373 | if (ptr->is_not) { | |
374 | flag = false; | |
375 | break; | |
376 | } | |
377 | flag = true; | |
378 | } | |
379 | up_read(&tomoyo_domain_initializer_list_lock); | |
380 | return flag; | |
381 | } | |
382 | ||
c3fa109a TH |
383 | /* |
384 | * tomoyo_domain_keeper_list is used for holding list of domainnames which | |
385 | * suppresses domain transition. Normally, a domainname is monotonically | |
386 | * getting longer. But sometimes, we want to suppress domain transition. | |
387 | * It would be convenient for us that programs executed from a login session | |
388 | * belong to the same domain. Thus, TOMOYO provides a way to suppress domain | |
389 | * transition. | |
390 | * | |
391 | * An entry is added by | |
392 | * | |
393 | * # echo 'keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \ | |
394 | * /sys/kernel/security/tomoyo/exception_policy | |
395 | * | |
396 | * and is deleted by | |
397 | * | |
398 | * # echo 'delete keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \ | |
399 | * /sys/kernel/security/tomoyo/exception_policy | |
400 | * | |
401 | * and all entries are retrieved by | |
402 | * | |
403 | * # grep ^keep_domain /sys/kernel/security/tomoyo/exception_policy | |
404 | * | |
405 | * In the example above, any process which belongs to | |
406 | * "<kernel> /usr/sbin/sshd /bin/bash" domain will remain in that domain, | |
407 | * unless explicitly specified by "initialize_domain" or "no_keep_domain". | |
408 | * | |
409 | * You may specify a program using "from" keyword. | |
410 | * "keep_domain /bin/pwd from <kernel> /usr/sbin/sshd /bin/bash" | |
411 | * will cause "/bin/pwd" executed from "<kernel> /usr/sbin/sshd /bin/bash" | |
412 | * domain to remain in "<kernel> /usr/sbin/sshd /bin/bash" domain. | |
413 | * | |
414 | * You may add "no_" prefix to "keep_domain". | |
415 | * "keep_domain <kernel> /usr/sbin/sshd /bin/bash" and | |
416 | * "no_keep_domain /usr/bin/passwd from <kernel> /usr/sbin/sshd /bin/bash" will | |
417 | * cause "/usr/bin/passwd" to belong to | |
418 | * "<kernel> /usr/sbin/sshd /bin/bash /usr/bin/passwd" domain, unless | |
419 | * explicitly specified by "initialize_domain". | |
420 | */ | |
26a2a1c9 KT |
421 | static LIST_HEAD(tomoyo_domain_keeper_list); |
422 | static DECLARE_RWSEM(tomoyo_domain_keeper_list_lock); | |
423 | ||
424 | /** | |
425 | * tomoyo_update_domain_keeper_entry - Update "struct tomoyo_domain_keeper_entry" list. | |
426 | * | |
427 | * @domainname: The name of domain. | |
428 | * @program: The name of program. May be NULL. | |
429 | * @is_not: True if it is "no_keep_domain" entry. | |
430 | * @is_delete: True if it is a delete request. | |
431 | * | |
432 | * Returns 0 on success, negative value otherwise. | |
433 | */ | |
434 | static int tomoyo_update_domain_keeper_entry(const char *domainname, | |
435 | const char *program, | |
436 | const bool is_not, | |
437 | const bool is_delete) | |
438 | { | |
439 | struct tomoyo_domain_keeper_entry *new_entry; | |
440 | struct tomoyo_domain_keeper_entry *ptr; | |
441 | const struct tomoyo_path_info *saved_domainname; | |
442 | const struct tomoyo_path_info *saved_program = NULL; | |
26a2a1c9 KT |
443 | int error = -ENOMEM; |
444 | bool is_last_name = false; | |
445 | ||
446 | if (!tomoyo_is_domain_def(domainname) && | |
447 | tomoyo_is_correct_path(domainname, 1, -1, -1, __func__)) | |
448 | is_last_name = true; | |
449 | else if (!tomoyo_is_correct_domain(domainname, __func__)) | |
450 | return -EINVAL; | |
451 | if (program) { | |
452 | if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__)) | |
453 | return -EINVAL; | |
454 | saved_program = tomoyo_save_name(program); | |
455 | if (!saved_program) | |
456 | return -ENOMEM; | |
457 | } | |
458 | saved_domainname = tomoyo_save_name(domainname); | |
459 | if (!saved_domainname) | |
460 | return -ENOMEM; | |
26a2a1c9 KT |
461 | down_write(&tomoyo_domain_keeper_list_lock); |
462 | list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) { | |
463 | if (ptr->is_not != is_not || | |
464 | ptr->domainname != saved_domainname || | |
465 | ptr->program != saved_program) | |
466 | continue; | |
467 | ptr->is_deleted = is_delete; | |
468 | error = 0; | |
469 | goto out; | |
470 | } | |
471 | if (is_delete) { | |
472 | error = -ENOENT; | |
473 | goto out; | |
474 | } | |
475 | new_entry = tomoyo_alloc_element(sizeof(*new_entry)); | |
476 | if (!new_entry) | |
477 | goto out; | |
478 | new_entry->domainname = saved_domainname; | |
479 | new_entry->program = saved_program; | |
480 | new_entry->is_not = is_not; | |
481 | new_entry->is_last_name = is_last_name; | |
482 | list_add_tail(&new_entry->list, &tomoyo_domain_keeper_list); | |
483 | error = 0; | |
484 | out: | |
485 | up_write(&tomoyo_domain_keeper_list_lock); | |
26a2a1c9 KT |
486 | return error; |
487 | } | |
488 | ||
489 | /** | |
490 | * tomoyo_write_domain_keeper_policy - Write "struct tomoyo_domain_keeper_entry" list. | |
491 | * | |
492 | * @data: String to parse. | |
493 | * @is_not: True if it is "no_keep_domain" entry. | |
494 | * @is_delete: True if it is a delete request. | |
495 | * | |
496 | */ | |
497 | int tomoyo_write_domain_keeper_policy(char *data, const bool is_not, | |
498 | const bool is_delete) | |
499 | { | |
500 | char *cp = strstr(data, " from "); | |
501 | ||
502 | if (cp) { | |
503 | *cp = '\0'; | |
504 | return tomoyo_update_domain_keeper_entry(cp + 6, data, is_not, | |
505 | is_delete); | |
506 | } | |
507 | return tomoyo_update_domain_keeper_entry(data, NULL, is_not, is_delete); | |
508 | } | |
509 | ||
510 | /** | |
511 | * tomoyo_read_domain_keeper_policy - Read "struct tomoyo_domain_keeper_entry" list. | |
512 | * | |
513 | * @head: Pointer to "struct tomoyo_io_buffer". | |
514 | * | |
515 | * Returns true on success, false otherwise. | |
516 | */ | |
517 | bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head) | |
518 | { | |
519 | struct list_head *pos; | |
33043cbb | 520 | bool done = true; |
26a2a1c9 KT |
521 | |
522 | down_read(&tomoyo_domain_keeper_list_lock); | |
523 | list_for_each_cookie(pos, head->read_var2, | |
524 | &tomoyo_domain_keeper_list) { | |
525 | struct tomoyo_domain_keeper_entry *ptr; | |
526 | const char *no; | |
527 | const char *from = ""; | |
528 | const char *program = ""; | |
529 | ||
530 | ptr = list_entry(pos, struct tomoyo_domain_keeper_entry, list); | |
531 | if (ptr->is_deleted) | |
532 | continue; | |
533 | no = ptr->is_not ? "no_" : ""; | |
534 | if (ptr->program) { | |
535 | from = " from "; | |
536 | program = ptr->program->name; | |
537 | } | |
7d2948b1 TH |
538 | done = tomoyo_io_printf(head, |
539 | "%s" TOMOYO_KEYWORD_KEEP_DOMAIN | |
540 | "%s%s%s\n", no, program, from, | |
541 | ptr->domainname->name); | |
542 | if (!done) | |
26a2a1c9 | 543 | break; |
26a2a1c9 KT |
544 | } |
545 | up_read(&tomoyo_domain_keeper_list_lock); | |
546 | return done; | |
547 | } | |
548 | ||
549 | /** | |
550 | * tomoyo_is_domain_keeper - Check whether the given program causes domain transition suppression. | |
551 | * | |
552 | * @domainname: The name of domain. | |
553 | * @program: The name of program. | |
554 | * @last_name: The last component of @domainname. | |
555 | * | |
556 | * Returns true if executing @program supresses domain transition, | |
557 | * false otherwise. | |
558 | */ | |
559 | static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname, | |
560 | const struct tomoyo_path_info *program, | |
561 | const struct tomoyo_path_info *last_name) | |
562 | { | |
563 | struct tomoyo_domain_keeper_entry *ptr; | |
564 | bool flag = false; | |
565 | ||
566 | down_read(&tomoyo_domain_keeper_list_lock); | |
567 | list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) { | |
568 | if (ptr->is_deleted) | |
569 | continue; | |
570 | if (!ptr->is_last_name) { | |
571 | if (ptr->domainname != domainname) | |
572 | continue; | |
573 | } else { | |
574 | if (tomoyo_pathcmp(ptr->domainname, last_name)) | |
575 | continue; | |
576 | } | |
577 | if (ptr->program && tomoyo_pathcmp(ptr->program, program)) | |
578 | continue; | |
579 | if (ptr->is_not) { | |
580 | flag = false; | |
581 | break; | |
582 | } | |
583 | flag = true; | |
584 | } | |
585 | up_read(&tomoyo_domain_keeper_list_lock); | |
586 | return flag; | |
587 | } | |
588 | ||
c3fa109a TH |
589 | /* |
590 | * tomoyo_alias_list is used for holding list of symlink's pathnames which are | |
591 | * allowed to be passed to an execve() request. Normally, the domainname which | |
592 | * the current process will belong to after execve() succeeds is calculated | |
593 | * using dereferenced pathnames. But some programs behave differently depending | |
594 | * on the name passed to argv[0]. For busybox, calculating domainname using | |
595 | * dereferenced pathnames will cause all programs in the busybox to belong to | |
596 | * the same domain. Thus, TOMOYO provides a way to allow use of symlink's | |
597 | * pathname for checking execve()'s permission and calculating domainname which | |
598 | * the current process will belong to after execve() succeeds. | |
599 | * | |
600 | * An entry is added by | |
601 | * | |
602 | * # echo 'alias /bin/busybox /bin/cat' > \ | |
603 | * /sys/kernel/security/tomoyo/exception_policy | |
604 | * | |
605 | * and is deleted by | |
606 | * | |
607 | * # echo 'delete alias /bin/busybox /bin/cat' > \ | |
608 | * /sys/kernel/security/tomoyo/exception_policy | |
609 | * | |
610 | * and all entries are retrieved by | |
611 | * | |
612 | * # grep ^alias /sys/kernel/security/tomoyo/exception_policy | |
613 | * | |
614 | * In the example above, if /bin/cat is a symlink to /bin/busybox and execution | |
615 | * of /bin/cat is requested, permission is checked for /bin/cat rather than | |
616 | * /bin/busybox and domainname which the current process will belong to after | |
617 | * execve() succeeds is calculated using /bin/cat rather than /bin/busybox . | |
618 | */ | |
26a2a1c9 KT |
619 | static LIST_HEAD(tomoyo_alias_list); |
620 | static DECLARE_RWSEM(tomoyo_alias_list_lock); | |
621 | ||
622 | /** | |
623 | * tomoyo_update_alias_entry - Update "struct tomoyo_alias_entry" list. | |
624 | * | |
625 | * @original_name: The original program's real name. | |
626 | * @aliased_name: The symbolic program's symbolic link's name. | |
627 | * @is_delete: True if it is a delete request. | |
628 | * | |
629 | * Returns 0 on success, negative value otherwise. | |
630 | */ | |
631 | static int tomoyo_update_alias_entry(const char *original_name, | |
632 | const char *aliased_name, | |
633 | const bool is_delete) | |
634 | { | |
635 | struct tomoyo_alias_entry *new_entry; | |
636 | struct tomoyo_alias_entry *ptr; | |
637 | const struct tomoyo_path_info *saved_original_name; | |
638 | const struct tomoyo_path_info *saved_aliased_name; | |
639 | int error = -ENOMEM; | |
640 | ||
641 | if (!tomoyo_is_correct_path(original_name, 1, -1, -1, __func__) || | |
642 | !tomoyo_is_correct_path(aliased_name, 1, -1, -1, __func__)) | |
643 | return -EINVAL; /* No patterns allowed. */ | |
644 | saved_original_name = tomoyo_save_name(original_name); | |
645 | saved_aliased_name = tomoyo_save_name(aliased_name); | |
646 | if (!saved_original_name || !saved_aliased_name) | |
647 | return -ENOMEM; | |
26a2a1c9 KT |
648 | down_write(&tomoyo_alias_list_lock); |
649 | list_for_each_entry(ptr, &tomoyo_alias_list, list) { | |
650 | if (ptr->original_name != saved_original_name || | |
651 | ptr->aliased_name != saved_aliased_name) | |
652 | continue; | |
653 | ptr->is_deleted = is_delete; | |
654 | error = 0; | |
655 | goto out; | |
656 | } | |
657 | if (is_delete) { | |
658 | error = -ENOENT; | |
659 | goto out; | |
660 | } | |
661 | new_entry = tomoyo_alloc_element(sizeof(*new_entry)); | |
662 | if (!new_entry) | |
663 | goto out; | |
664 | new_entry->original_name = saved_original_name; | |
665 | new_entry->aliased_name = saved_aliased_name; | |
666 | list_add_tail(&new_entry->list, &tomoyo_alias_list); | |
667 | error = 0; | |
668 | out: | |
669 | up_write(&tomoyo_alias_list_lock); | |
26a2a1c9 KT |
670 | return error; |
671 | } | |
672 | ||
673 | /** | |
674 | * tomoyo_read_alias_policy - Read "struct tomoyo_alias_entry" list. | |
675 | * | |
676 | * @head: Pointer to "struct tomoyo_io_buffer". | |
677 | * | |
678 | * Returns true on success, false otherwise. | |
679 | */ | |
680 | bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head) | |
681 | { | |
682 | struct list_head *pos; | |
683 | bool done = true; | |
684 | ||
685 | down_read(&tomoyo_alias_list_lock); | |
686 | list_for_each_cookie(pos, head->read_var2, &tomoyo_alias_list) { | |
687 | struct tomoyo_alias_entry *ptr; | |
688 | ||
689 | ptr = list_entry(pos, struct tomoyo_alias_entry, list); | |
690 | if (ptr->is_deleted) | |
691 | continue; | |
7d2948b1 TH |
692 | done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n", |
693 | ptr->original_name->name, | |
694 | ptr->aliased_name->name); | |
695 | if (!done) | |
26a2a1c9 | 696 | break; |
26a2a1c9 KT |
697 | } |
698 | up_read(&tomoyo_alias_list_lock); | |
699 | return done; | |
700 | } | |
701 | ||
702 | /** | |
703 | * tomoyo_write_alias_policy - Write "struct tomoyo_alias_entry" list. | |
704 | * | |
705 | * @data: String to parse. | |
706 | * @is_delete: True if it is a delete request. | |
707 | * | |
708 | * Returns 0 on success, negative value otherwise. | |
709 | */ | |
710 | int tomoyo_write_alias_policy(char *data, const bool is_delete) | |
711 | { | |
712 | char *cp = strchr(data, ' '); | |
713 | ||
714 | if (!cp) | |
715 | return -EINVAL; | |
716 | *cp++ = '\0'; | |
717 | return tomoyo_update_alias_entry(data, cp, is_delete); | |
718 | } | |
719 | ||
a0558fc3 | 720 | /* Domain create/delete handler. */ |
26a2a1c9 KT |
721 | |
722 | /** | |
723 | * tomoyo_delete_domain - Delete a domain. | |
724 | * | |
725 | * @domainname: The name of domain. | |
726 | * | |
727 | * Returns 0. | |
728 | */ | |
729 | int tomoyo_delete_domain(char *domainname) | |
730 | { | |
731 | struct tomoyo_domain_info *domain; | |
732 | struct tomoyo_path_info name; | |
733 | ||
734 | name.name = domainname; | |
735 | tomoyo_fill_path_info(&name); | |
26a2a1c9 | 736 | down_write(&tomoyo_domain_list_lock); |
26a2a1c9 KT |
737 | /* Is there an active domain? */ |
738 | list_for_each_entry(domain, &tomoyo_domain_list, list) { | |
26a2a1c9 KT |
739 | /* Never delete tomoyo_kernel_domain */ |
740 | if (domain == &tomoyo_kernel_domain) | |
741 | continue; | |
742 | if (domain->is_deleted || | |
743 | tomoyo_pathcmp(domain->domainname, &name)) | |
744 | continue; | |
a0558fc3 | 745 | domain->is_deleted = true; |
26a2a1c9 KT |
746 | break; |
747 | } | |
748 | up_write(&tomoyo_domain_list_lock); | |
26a2a1c9 KT |
749 | return 0; |
750 | } | |
751 | ||
26a2a1c9 KT |
752 | /** |
753 | * tomoyo_find_or_assign_new_domain - Create a domain. | |
754 | * | |
755 | * @domainname: The name of domain. | |
756 | * @profile: Profile number to assign if the domain was newly created. | |
757 | * | |
758 | * Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise. | |
759 | */ | |
760 | struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * | |
761 | domainname, | |
762 | const u8 profile) | |
763 | { | |
764 | struct tomoyo_domain_info *domain = NULL; | |
765 | const struct tomoyo_path_info *saved_domainname; | |
766 | ||
26a2a1c9 KT |
767 | down_write(&tomoyo_domain_list_lock); |
768 | domain = tomoyo_find_domain(domainname); | |
769 | if (domain) | |
770 | goto out; | |
771 | if (!tomoyo_is_correct_domain(domainname, __func__)) | |
772 | goto out; | |
773 | saved_domainname = tomoyo_save_name(domainname); | |
774 | if (!saved_domainname) | |
775 | goto out; | |
776 | /* Can I reuse memory of deleted domain? */ | |
777 | list_for_each_entry(domain, &tomoyo_domain_list, list) { | |
778 | struct task_struct *p; | |
779 | struct tomoyo_acl_info *ptr; | |
780 | bool flag; | |
781 | if (!domain->is_deleted || | |
782 | domain->domainname != saved_domainname) | |
783 | continue; | |
784 | flag = false; | |
26a2a1c9 KT |
785 | read_lock(&tasklist_lock); |
786 | for_each_process(p) { | |
787 | if (tomoyo_real_domain(p) != domain) | |
788 | continue; | |
789 | flag = true; | |
790 | break; | |
791 | } | |
792 | read_unlock(&tasklist_lock); | |
26a2a1c9 KT |
793 | if (flag) |
794 | continue; | |
26a2a1c9 KT |
795 | list_for_each_entry(ptr, &domain->acl_info_list, list) { |
796 | ptr->type |= TOMOYO_ACL_DELETED; | |
797 | } | |
798 | tomoyo_set_domain_flag(domain, true, domain->flags); | |
799 | domain->profile = profile; | |
800 | domain->quota_warned = false; | |
801 | mb(); /* Avoid out-of-order execution. */ | |
a0558fc3 | 802 | domain->is_deleted = false; |
26a2a1c9 KT |
803 | goto out; |
804 | } | |
805 | /* No memory reusable. Create using new memory. */ | |
806 | domain = tomoyo_alloc_element(sizeof(*domain)); | |
807 | if (domain) { | |
808 | INIT_LIST_HEAD(&domain->acl_info_list); | |
809 | domain->domainname = saved_domainname; | |
810 | domain->profile = profile; | |
811 | list_add_tail(&domain->list, &tomoyo_domain_list); | |
812 | } | |
813 | out: | |
814 | up_write(&tomoyo_domain_list_lock); | |
26a2a1c9 KT |
815 | return domain; |
816 | } | |
817 | ||
818 | /** | |
819 | * tomoyo_find_next_domain - Find a domain. | |
820 | * | |
821 | * @bprm: Pointer to "struct linux_binprm". | |
822 | * @next_domain: Pointer to pointer to "struct tomoyo_domain_info". | |
823 | * | |
824 | * Returns 0 on success, negative value otherwise. | |
825 | */ | |
826 | int tomoyo_find_next_domain(struct linux_binprm *bprm, | |
827 | struct tomoyo_domain_info **next_domain) | |
828 | { | |
829 | /* | |
830 | * This function assumes that the size of buffer returned by | |
831 | * tomoyo_realpath() = TOMOYO_MAX_PATHNAME_LEN. | |
832 | */ | |
833 | struct tomoyo_page_buffer *tmp = tomoyo_alloc(sizeof(*tmp)); | |
834 | struct tomoyo_domain_info *old_domain = tomoyo_domain(); | |
835 | struct tomoyo_domain_info *domain = NULL; | |
836 | const char *old_domain_name = old_domain->domainname->name; | |
837 | const char *original_name = bprm->filename; | |
838 | char *new_domain_name = NULL; | |
839 | char *real_program_name = NULL; | |
840 | char *symlink_program_name = NULL; | |
841 | const u8 mode = tomoyo_check_flags(old_domain, TOMOYO_MAC_FOR_FILE); | |
842 | const bool is_enforce = (mode == 3); | |
843 | int retval = -ENOMEM; | |
844 | struct tomoyo_path_info r; /* real name */ | |
845 | struct tomoyo_path_info s; /* symlink name */ | |
846 | struct tomoyo_path_info l; /* last name */ | |
847 | static bool initialized; | |
848 | ||
849 | if (!tmp) | |
850 | goto out; | |
851 | ||
852 | if (!initialized) { | |
853 | /* | |
854 | * Built-in initializers. This is needed because policies are | |
855 | * not loaded until starting /sbin/init. | |
856 | */ | |
857 | tomoyo_update_domain_initializer_entry(NULL, "/sbin/hotplug", | |
858 | false, false); | |
859 | tomoyo_update_domain_initializer_entry(NULL, "/sbin/modprobe", | |
860 | false, false); | |
861 | initialized = true; | |
862 | } | |
863 | ||
864 | /* Get tomoyo_realpath of program. */ | |
865 | retval = -ENOENT; | |
866 | /* I hope tomoyo_realpath() won't fail with -ENOMEM. */ | |
867 | real_program_name = tomoyo_realpath(original_name); | |
868 | if (!real_program_name) | |
869 | goto out; | |
870 | /* Get tomoyo_realpath of symbolic link. */ | |
871 | symlink_program_name = tomoyo_realpath_nofollow(original_name); | |
872 | if (!symlink_program_name) | |
873 | goto out; | |
874 | ||
875 | r.name = real_program_name; | |
876 | tomoyo_fill_path_info(&r); | |
877 | s.name = symlink_program_name; | |
878 | tomoyo_fill_path_info(&s); | |
879 | l.name = tomoyo_get_last_name(old_domain); | |
880 | tomoyo_fill_path_info(&l); | |
881 | ||
882 | /* Check 'alias' directive. */ | |
883 | if (tomoyo_pathcmp(&r, &s)) { | |
884 | struct tomoyo_alias_entry *ptr; | |
885 | /* Is this program allowed to be called via symbolic links? */ | |
886 | down_read(&tomoyo_alias_list_lock); | |
887 | list_for_each_entry(ptr, &tomoyo_alias_list, list) { | |
888 | if (ptr->is_deleted || | |
889 | tomoyo_pathcmp(&r, ptr->original_name) || | |
890 | tomoyo_pathcmp(&s, ptr->aliased_name)) | |
891 | continue; | |
892 | memset(real_program_name, 0, TOMOYO_MAX_PATHNAME_LEN); | |
893 | strncpy(real_program_name, ptr->aliased_name->name, | |
894 | TOMOYO_MAX_PATHNAME_LEN - 1); | |
895 | tomoyo_fill_path_info(&r); | |
896 | break; | |
897 | } | |
898 | up_read(&tomoyo_alias_list_lock); | |
899 | } | |
900 | ||
901 | /* Check execute permission. */ | |
bcb86975 | 902 | retval = tomoyo_check_exec_perm(old_domain, &r); |
26a2a1c9 KT |
903 | if (retval < 0) |
904 | goto out; | |
905 | ||
906 | new_domain_name = tmp->buffer; | |
907 | if (tomoyo_is_domain_initializer(old_domain->domainname, &r, &l)) { | |
908 | /* Transit to the child of tomoyo_kernel_domain domain. */ | |
909 | snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1, | |
910 | TOMOYO_ROOT_NAME " " "%s", real_program_name); | |
911 | } else if (old_domain == &tomoyo_kernel_domain && | |
912 | !tomoyo_policy_loaded) { | |
913 | /* | |
914 | * Needn't to transit from kernel domain before starting | |
915 | * /sbin/init. But transit from kernel domain if executing | |
916 | * initializers because they might start before /sbin/init. | |
917 | */ | |
918 | domain = old_domain; | |
919 | } else if (tomoyo_is_domain_keeper(old_domain->domainname, &r, &l)) { | |
920 | /* Keep current domain. */ | |
921 | domain = old_domain; | |
922 | } else { | |
923 | /* Normal domain transition. */ | |
924 | snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1, | |
925 | "%s %s", old_domain_name, real_program_name); | |
926 | } | |
927 | if (domain || strlen(new_domain_name) >= TOMOYO_MAX_PATHNAME_LEN) | |
928 | goto done; | |
929 | down_read(&tomoyo_domain_list_lock); | |
930 | domain = tomoyo_find_domain(new_domain_name); | |
931 | up_read(&tomoyo_domain_list_lock); | |
932 | if (domain) | |
933 | goto done; | |
934 | if (is_enforce) | |
935 | goto done; | |
936 | domain = tomoyo_find_or_assign_new_domain(new_domain_name, | |
937 | old_domain->profile); | |
938 | done: | |
939 | if (domain) | |
940 | goto out; | |
941 | printk(KERN_WARNING "TOMOYO-ERROR: Domain '%s' not defined.\n", | |
942 | new_domain_name); | |
943 | if (is_enforce) | |
944 | retval = -EPERM; | |
945 | else | |
946 | tomoyo_set_domain_flag(old_domain, false, | |
947 | TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED); | |
948 | out: | |
949 | tomoyo_free(real_program_name); | |
950 | tomoyo_free(symlink_program_name); | |
951 | *next_domain = domain ? domain : old_domain; | |
952 | tomoyo_free(tmp); | |
953 | return retval; | |
954 | } |