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Commit | Line | Data |
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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" | |
26a2a1c9 | 13 | #include <linux/binfmts.h> |
5a0e3ad6 | 14 | #include <linux/slab.h> |
26a2a1c9 KT |
15 | |
16 | /* Variables definitions.*/ | |
17 | ||
18 | /* The initial domain. */ | |
19 | struct tomoyo_domain_info tomoyo_kernel_domain; | |
20 | ||
c3fa109a TH |
21 | /* |
22 | * tomoyo_domain_list is used for holding list of domains. | |
23 | * The ->acl_info_list of "struct tomoyo_domain_info" is used for holding | |
24 | * permissions (e.g. "allow_read /lib/libc-2.5.so") given to each domain. | |
25 | * | |
26 | * An entry is added by | |
27 | * | |
28 | * # ( echo "<kernel>"; echo "allow_execute /sbin/init" ) > \ | |
29 | * /sys/kernel/security/tomoyo/domain_policy | |
30 | * | |
31 | * and is deleted by | |
32 | * | |
33 | * # ( echo "<kernel>"; echo "delete allow_execute /sbin/init" ) > \ | |
34 | * /sys/kernel/security/tomoyo/domain_policy | |
35 | * | |
36 | * and all entries are retrieved by | |
37 | * | |
38 | * # cat /sys/kernel/security/tomoyo/domain_policy | |
39 | * | |
40 | * A domain is added by | |
41 | * | |
42 | * # echo "<kernel>" > /sys/kernel/security/tomoyo/domain_policy | |
43 | * | |
44 | * and is deleted by | |
45 | * | |
46 | * # echo "delete <kernel>" > /sys/kernel/security/tomoyo/domain_policy | |
47 | * | |
48 | * and all domains are retrieved by | |
49 | * | |
50 | * # grep '^<kernel>' /sys/kernel/security/tomoyo/domain_policy | |
51 | * | |
52 | * Normally, a domainname is monotonically getting longer because a domainname | |
53 | * which the process will belong to if an execve() operation succeeds is | |
54 | * defined as a concatenation of "current domainname" + "pathname passed to | |
55 | * execve()". | |
56 | * See tomoyo_domain_initializer_list and tomoyo_domain_keeper_list for | |
57 | * exceptions. | |
58 | */ | |
26a2a1c9 | 59 | LIST_HEAD(tomoyo_domain_list); |
26a2a1c9 | 60 | |
26a2a1c9 KT |
61 | /** |
62 | * tomoyo_get_last_name - Get last component of a domainname. | |
63 | * | |
64 | * @domain: Pointer to "struct tomoyo_domain_info". | |
65 | * | |
66 | * Returns the last component of the domainname. | |
67 | */ | |
68 | const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain) | |
69 | { | |
70 | const char *cp0 = domain->domainname->name; | |
71 | const char *cp1 = strrchr(cp0, ' '); | |
72 | ||
73 | if (cp1) | |
74 | return cp1 + 1; | |
75 | return cp0; | |
76 | } | |
77 | ||
c3fa109a TH |
78 | /* |
79 | * tomoyo_domain_initializer_list is used for holding list of programs which | |
80 | * triggers reinitialization of domainname. Normally, a domainname is | |
81 | * monotonically getting longer. But sometimes, we restart daemon programs. | |
82 | * It would be convenient for us that "a daemon started upon system boot" and | |
83 | * "the daemon restarted from console" belong to the same domain. Thus, TOMOYO | |
84 | * provides a way to shorten domainnames. | |
85 | * | |
86 | * An entry is added by | |
87 | * | |
88 | * # echo 'initialize_domain /usr/sbin/httpd' > \ | |
89 | * /sys/kernel/security/tomoyo/exception_policy | |
90 | * | |
91 | * and is deleted by | |
92 | * | |
93 | * # echo 'delete initialize_domain /usr/sbin/httpd' > \ | |
94 | * /sys/kernel/security/tomoyo/exception_policy | |
95 | * | |
96 | * and all entries are retrieved by | |
97 | * | |
98 | * # grep ^initialize_domain /sys/kernel/security/tomoyo/exception_policy | |
99 | * | |
100 | * In the example above, /usr/sbin/httpd will belong to | |
101 | * "<kernel> /usr/sbin/httpd" domain. | |
102 | * | |
103 | * You may specify a domainname using "from" keyword. | |
104 | * "initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd" | |
105 | * will cause "/usr/sbin/httpd" executed from "<kernel> /etc/rc.d/init.d/httpd" | |
106 | * domain to belong to "<kernel> /usr/sbin/httpd" domain. | |
107 | * | |
108 | * You may add "no_" prefix to "initialize_domain". | |
109 | * "initialize_domain /usr/sbin/httpd" and | |
110 | * "no_initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd" | |
111 | * will cause "/usr/sbin/httpd" to belong to "<kernel> /usr/sbin/httpd" domain | |
112 | * unless executed from "<kernel> /etc/rc.d/init.d/httpd" domain. | |
113 | */ | |
847b173e | 114 | LIST_HEAD(tomoyo_domain_initializer_list); |
26a2a1c9 KT |
115 | |
116 | /** | |
117 | * tomoyo_update_domain_initializer_entry - Update "struct tomoyo_domain_initializer_entry" list. | |
118 | * | |
119 | * @domainname: The name of domain. May be NULL. | |
120 | * @program: The name of program. | |
121 | * @is_not: True if it is "no_initialize_domain" entry. | |
122 | * @is_delete: True if it is a delete request. | |
123 | * | |
124 | * Returns 0 on success, negative value otherwise. | |
fdb8ebb7 TH |
125 | * |
126 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
127 | */ |
128 | static int tomoyo_update_domain_initializer_entry(const char *domainname, | |
129 | const char *program, | |
130 | const bool is_not, | |
131 | const bool is_delete) | |
132 | { | |
26a2a1c9 | 133 | struct tomoyo_domain_initializer_entry *ptr; |
9e4b50e9 | 134 | struct tomoyo_domain_initializer_entry e = { .is_not = is_not }; |
ca0b7df3 | 135 | int error = is_delete ? -ENOENT : -ENOMEM; |
26a2a1c9 | 136 | |
17080008 | 137 | if (!tomoyo_is_correct_path(program, 1, -1, -1)) |
26a2a1c9 KT |
138 | return -EINVAL; /* No patterns allowed. */ |
139 | if (domainname) { | |
140 | if (!tomoyo_is_domain_def(domainname) && | |
17080008 | 141 | tomoyo_is_correct_path(domainname, 1, -1, -1)) |
9e4b50e9 | 142 | e.is_last_name = true; |
17080008 | 143 | else if (!tomoyo_is_correct_domain(domainname)) |
26a2a1c9 | 144 | return -EINVAL; |
9e4b50e9 TH |
145 | e.domainname = tomoyo_get_name(domainname); |
146 | if (!e.domainname) | |
ca0b7df3 | 147 | goto out; |
26a2a1c9 | 148 | } |
9e4b50e9 TH |
149 | e.program = tomoyo_get_name(program); |
150 | if (!e.program) | |
ca0b7df3 | 151 | goto out; |
29282381 TH |
152 | if (mutex_lock_interruptible(&tomoyo_policy_lock)) |
153 | goto out; | |
fdb8ebb7 | 154 | list_for_each_entry_rcu(ptr, &tomoyo_domain_initializer_list, list) { |
9e4b50e9 | 155 | if (!tomoyo_is_same_domain_initializer_entry(ptr, &e)) |
26a2a1c9 KT |
156 | continue; |
157 | ptr->is_deleted = is_delete; | |
158 | error = 0; | |
ca0b7df3 | 159 | break; |
26a2a1c9 | 160 | } |
9e4b50e9 TH |
161 | if (!is_delete && error) { |
162 | struct tomoyo_domain_initializer_entry *entry = | |
163 | tomoyo_commit_ok(&e, sizeof(e)); | |
164 | if (entry) { | |
165 | list_add_tail_rcu(&entry->list, | |
166 | &tomoyo_domain_initializer_list); | |
167 | error = 0; | |
168 | } | |
26a2a1c9 | 169 | } |
f737d95d | 170 | mutex_unlock(&tomoyo_policy_lock); |
ca0b7df3 | 171 | out: |
9e4b50e9 TH |
172 | tomoyo_put_name(e.domainname); |
173 | tomoyo_put_name(e.program); | |
26a2a1c9 KT |
174 | return error; |
175 | } | |
176 | ||
177 | /** | |
178 | * tomoyo_read_domain_initializer_policy - Read "struct tomoyo_domain_initializer_entry" list. | |
179 | * | |
180 | * @head: Pointer to "struct tomoyo_io_buffer". | |
181 | * | |
182 | * Returns true on success, false otherwise. | |
fdb8ebb7 TH |
183 | * |
184 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
185 | */ |
186 | bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head) | |
187 | { | |
188 | struct list_head *pos; | |
189 | bool done = true; | |
190 | ||
26a2a1c9 KT |
191 | list_for_each_cookie(pos, head->read_var2, |
192 | &tomoyo_domain_initializer_list) { | |
193 | const char *no; | |
194 | const char *from = ""; | |
195 | const char *domain = ""; | |
196 | struct tomoyo_domain_initializer_entry *ptr; | |
197 | ptr = list_entry(pos, struct tomoyo_domain_initializer_entry, | |
198 | list); | |
199 | if (ptr->is_deleted) | |
200 | continue; | |
201 | no = ptr->is_not ? "no_" : ""; | |
202 | if (ptr->domainname) { | |
203 | from = " from "; | |
204 | domain = ptr->domainname->name; | |
205 | } | |
7d2948b1 TH |
206 | done = tomoyo_io_printf(head, |
207 | "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN | |
208 | "%s%s%s\n", no, ptr->program->name, | |
209 | from, domain); | |
210 | if (!done) | |
26a2a1c9 | 211 | break; |
26a2a1c9 | 212 | } |
26a2a1c9 KT |
213 | return done; |
214 | } | |
215 | ||
216 | /** | |
217 | * tomoyo_write_domain_initializer_policy - Write "struct tomoyo_domain_initializer_entry" list. | |
218 | * | |
219 | * @data: String to parse. | |
220 | * @is_not: True if it is "no_initialize_domain" entry. | |
221 | * @is_delete: True if it is a delete request. | |
222 | * | |
223 | * Returns 0 on success, negative value otherwise. | |
fdb8ebb7 TH |
224 | * |
225 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
226 | */ |
227 | int tomoyo_write_domain_initializer_policy(char *data, const bool is_not, | |
228 | const bool is_delete) | |
229 | { | |
230 | char *cp = strstr(data, " from "); | |
231 | ||
232 | if (cp) { | |
233 | *cp = '\0'; | |
234 | return tomoyo_update_domain_initializer_entry(cp + 6, data, | |
235 | is_not, | |
236 | is_delete); | |
237 | } | |
238 | return tomoyo_update_domain_initializer_entry(NULL, data, is_not, | |
239 | is_delete); | |
240 | } | |
241 | ||
242 | /** | |
243 | * tomoyo_is_domain_initializer - Check whether the given program causes domainname reinitialization. | |
244 | * | |
245 | * @domainname: The name of domain. | |
246 | * @program: The name of program. | |
247 | * @last_name: The last component of @domainname. | |
248 | * | |
249 | * Returns true if executing @program reinitializes domain transition, | |
250 | * false otherwise. | |
fdb8ebb7 TH |
251 | * |
252 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
253 | */ |
254 | static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info * | |
255 | domainname, | |
256 | const struct tomoyo_path_info *program, | |
257 | const struct tomoyo_path_info * | |
258 | last_name) | |
259 | { | |
260 | struct tomoyo_domain_initializer_entry *ptr; | |
261 | bool flag = false; | |
262 | ||
fdb8ebb7 | 263 | list_for_each_entry_rcu(ptr, &tomoyo_domain_initializer_list, list) { |
26a2a1c9 KT |
264 | if (ptr->is_deleted) |
265 | continue; | |
266 | if (ptr->domainname) { | |
267 | if (!ptr->is_last_name) { | |
268 | if (ptr->domainname != domainname) | |
269 | continue; | |
270 | } else { | |
271 | if (tomoyo_pathcmp(ptr->domainname, last_name)) | |
272 | continue; | |
273 | } | |
274 | } | |
275 | if (tomoyo_pathcmp(ptr->program, program)) | |
276 | continue; | |
277 | if (ptr->is_not) { | |
278 | flag = false; | |
279 | break; | |
280 | } | |
281 | flag = true; | |
282 | } | |
26a2a1c9 KT |
283 | return flag; |
284 | } | |
285 | ||
c3fa109a TH |
286 | /* |
287 | * tomoyo_domain_keeper_list is used for holding list of domainnames which | |
288 | * suppresses domain transition. Normally, a domainname is monotonically | |
289 | * getting longer. But sometimes, we want to suppress domain transition. | |
290 | * It would be convenient for us that programs executed from a login session | |
291 | * belong to the same domain. Thus, TOMOYO provides a way to suppress domain | |
292 | * transition. | |
293 | * | |
294 | * An entry is added by | |
295 | * | |
296 | * # echo 'keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \ | |
297 | * /sys/kernel/security/tomoyo/exception_policy | |
298 | * | |
299 | * and is deleted by | |
300 | * | |
301 | * # echo 'delete keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \ | |
302 | * /sys/kernel/security/tomoyo/exception_policy | |
303 | * | |
304 | * and all entries are retrieved by | |
305 | * | |
306 | * # grep ^keep_domain /sys/kernel/security/tomoyo/exception_policy | |
307 | * | |
308 | * In the example above, any process which belongs to | |
309 | * "<kernel> /usr/sbin/sshd /bin/bash" domain will remain in that domain, | |
310 | * unless explicitly specified by "initialize_domain" or "no_keep_domain". | |
311 | * | |
312 | * You may specify a program using "from" keyword. | |
313 | * "keep_domain /bin/pwd from <kernel> /usr/sbin/sshd /bin/bash" | |
314 | * will cause "/bin/pwd" executed from "<kernel> /usr/sbin/sshd /bin/bash" | |
315 | * domain to remain in "<kernel> /usr/sbin/sshd /bin/bash" domain. | |
316 | * | |
317 | * You may add "no_" prefix to "keep_domain". | |
318 | * "keep_domain <kernel> /usr/sbin/sshd /bin/bash" and | |
319 | * "no_keep_domain /usr/bin/passwd from <kernel> /usr/sbin/sshd /bin/bash" will | |
320 | * cause "/usr/bin/passwd" to belong to | |
321 | * "<kernel> /usr/sbin/sshd /bin/bash /usr/bin/passwd" domain, unless | |
322 | * explicitly specified by "initialize_domain". | |
323 | */ | |
847b173e | 324 | LIST_HEAD(tomoyo_domain_keeper_list); |
26a2a1c9 KT |
325 | |
326 | /** | |
327 | * tomoyo_update_domain_keeper_entry - Update "struct tomoyo_domain_keeper_entry" list. | |
328 | * | |
329 | * @domainname: The name of domain. | |
330 | * @program: The name of program. May be NULL. | |
331 | * @is_not: True if it is "no_keep_domain" entry. | |
332 | * @is_delete: True if it is a delete request. | |
333 | * | |
334 | * Returns 0 on success, negative value otherwise. | |
fdb8ebb7 TH |
335 | * |
336 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
337 | */ |
338 | static int tomoyo_update_domain_keeper_entry(const char *domainname, | |
339 | const char *program, | |
340 | const bool is_not, | |
341 | const bool is_delete) | |
342 | { | |
26a2a1c9 | 343 | struct tomoyo_domain_keeper_entry *ptr; |
9e4b50e9 | 344 | struct tomoyo_domain_keeper_entry e = { .is_not = is_not }; |
ca0b7df3 | 345 | int error = is_delete ? -ENOENT : -ENOMEM; |
26a2a1c9 KT |
346 | |
347 | if (!tomoyo_is_domain_def(domainname) && | |
17080008 | 348 | tomoyo_is_correct_path(domainname, 1, -1, -1)) |
9e4b50e9 | 349 | e.is_last_name = true; |
17080008 | 350 | else if (!tomoyo_is_correct_domain(domainname)) |
26a2a1c9 KT |
351 | return -EINVAL; |
352 | if (program) { | |
17080008 | 353 | if (!tomoyo_is_correct_path(program, 1, -1, -1)) |
26a2a1c9 | 354 | return -EINVAL; |
9e4b50e9 TH |
355 | e.program = tomoyo_get_name(program); |
356 | if (!e.program) | |
ca0b7df3 | 357 | goto out; |
26a2a1c9 | 358 | } |
9e4b50e9 TH |
359 | e.domainname = tomoyo_get_name(domainname); |
360 | if (!e.domainname) | |
ca0b7df3 | 361 | goto out; |
29282381 TH |
362 | if (mutex_lock_interruptible(&tomoyo_policy_lock)) |
363 | goto out; | |
fdb8ebb7 | 364 | list_for_each_entry_rcu(ptr, &tomoyo_domain_keeper_list, list) { |
9e4b50e9 | 365 | if (!tomoyo_is_same_domain_keeper_entry(ptr, &e)) |
26a2a1c9 KT |
366 | continue; |
367 | ptr->is_deleted = is_delete; | |
368 | error = 0; | |
ca0b7df3 | 369 | break; |
26a2a1c9 | 370 | } |
9e4b50e9 TH |
371 | if (!is_delete && error) { |
372 | struct tomoyo_domain_keeper_entry *entry = | |
373 | tomoyo_commit_ok(&e, sizeof(e)); | |
374 | if (entry) { | |
375 | list_add_tail_rcu(&entry->list, | |
376 | &tomoyo_domain_keeper_list); | |
377 | error = 0; | |
378 | } | |
26a2a1c9 | 379 | } |
f737d95d | 380 | mutex_unlock(&tomoyo_policy_lock); |
ca0b7df3 | 381 | out: |
9e4b50e9 TH |
382 | tomoyo_put_name(e.domainname); |
383 | tomoyo_put_name(e.program); | |
26a2a1c9 KT |
384 | return error; |
385 | } | |
386 | ||
387 | /** | |
388 | * tomoyo_write_domain_keeper_policy - Write "struct tomoyo_domain_keeper_entry" list. | |
389 | * | |
390 | * @data: String to parse. | |
391 | * @is_not: True if it is "no_keep_domain" entry. | |
392 | * @is_delete: True if it is a delete request. | |
393 | * | |
fdb8ebb7 | 394 | * Caller holds tomoyo_read_lock(). |
26a2a1c9 KT |
395 | */ |
396 | int tomoyo_write_domain_keeper_policy(char *data, const bool is_not, | |
397 | const bool is_delete) | |
398 | { | |
399 | char *cp = strstr(data, " from "); | |
400 | ||
401 | if (cp) { | |
402 | *cp = '\0'; | |
403 | return tomoyo_update_domain_keeper_entry(cp + 6, data, is_not, | |
404 | is_delete); | |
405 | } | |
406 | return tomoyo_update_domain_keeper_entry(data, NULL, is_not, is_delete); | |
407 | } | |
408 | ||
409 | /** | |
410 | * tomoyo_read_domain_keeper_policy - Read "struct tomoyo_domain_keeper_entry" list. | |
411 | * | |
412 | * @head: Pointer to "struct tomoyo_io_buffer". | |
413 | * | |
414 | * Returns true on success, false otherwise. | |
fdb8ebb7 TH |
415 | * |
416 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
417 | */ |
418 | bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head) | |
419 | { | |
420 | struct list_head *pos; | |
33043cbb | 421 | bool done = true; |
26a2a1c9 | 422 | |
26a2a1c9 KT |
423 | list_for_each_cookie(pos, head->read_var2, |
424 | &tomoyo_domain_keeper_list) { | |
425 | struct tomoyo_domain_keeper_entry *ptr; | |
426 | const char *no; | |
427 | const char *from = ""; | |
428 | const char *program = ""; | |
429 | ||
430 | ptr = list_entry(pos, struct tomoyo_domain_keeper_entry, list); | |
431 | if (ptr->is_deleted) | |
432 | continue; | |
433 | no = ptr->is_not ? "no_" : ""; | |
434 | if (ptr->program) { | |
435 | from = " from "; | |
436 | program = ptr->program->name; | |
437 | } | |
7d2948b1 TH |
438 | done = tomoyo_io_printf(head, |
439 | "%s" TOMOYO_KEYWORD_KEEP_DOMAIN | |
440 | "%s%s%s\n", no, program, from, | |
441 | ptr->domainname->name); | |
442 | if (!done) | |
26a2a1c9 | 443 | break; |
26a2a1c9 | 444 | } |
26a2a1c9 KT |
445 | return done; |
446 | } | |
447 | ||
448 | /** | |
449 | * tomoyo_is_domain_keeper - Check whether the given program causes domain transition suppression. | |
450 | * | |
451 | * @domainname: The name of domain. | |
452 | * @program: The name of program. | |
453 | * @last_name: The last component of @domainname. | |
454 | * | |
455 | * Returns true if executing @program supresses domain transition, | |
456 | * false otherwise. | |
fdb8ebb7 TH |
457 | * |
458 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
459 | */ |
460 | static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname, | |
461 | const struct tomoyo_path_info *program, | |
462 | const struct tomoyo_path_info *last_name) | |
463 | { | |
464 | struct tomoyo_domain_keeper_entry *ptr; | |
465 | bool flag = false; | |
466 | ||
fdb8ebb7 | 467 | list_for_each_entry_rcu(ptr, &tomoyo_domain_keeper_list, list) { |
26a2a1c9 KT |
468 | if (ptr->is_deleted) |
469 | continue; | |
470 | if (!ptr->is_last_name) { | |
471 | if (ptr->domainname != domainname) | |
472 | continue; | |
473 | } else { | |
474 | if (tomoyo_pathcmp(ptr->domainname, last_name)) | |
475 | continue; | |
476 | } | |
477 | if (ptr->program && tomoyo_pathcmp(ptr->program, program)) | |
478 | continue; | |
479 | if (ptr->is_not) { | |
480 | flag = false; | |
481 | break; | |
482 | } | |
483 | flag = true; | |
484 | } | |
26a2a1c9 KT |
485 | return flag; |
486 | } | |
487 | ||
c3fa109a TH |
488 | /* |
489 | * tomoyo_alias_list is used for holding list of symlink's pathnames which are | |
490 | * allowed to be passed to an execve() request. Normally, the domainname which | |
491 | * the current process will belong to after execve() succeeds is calculated | |
492 | * using dereferenced pathnames. But some programs behave differently depending | |
493 | * on the name passed to argv[0]. For busybox, calculating domainname using | |
494 | * dereferenced pathnames will cause all programs in the busybox to belong to | |
495 | * the same domain. Thus, TOMOYO provides a way to allow use of symlink's | |
496 | * pathname for checking execve()'s permission and calculating domainname which | |
497 | * the current process will belong to after execve() succeeds. | |
498 | * | |
499 | * An entry is added by | |
500 | * | |
501 | * # echo 'alias /bin/busybox /bin/cat' > \ | |
502 | * /sys/kernel/security/tomoyo/exception_policy | |
503 | * | |
504 | * and is deleted by | |
505 | * | |
506 | * # echo 'delete alias /bin/busybox /bin/cat' > \ | |
507 | * /sys/kernel/security/tomoyo/exception_policy | |
508 | * | |
509 | * and all entries are retrieved by | |
510 | * | |
511 | * # grep ^alias /sys/kernel/security/tomoyo/exception_policy | |
512 | * | |
513 | * In the example above, if /bin/cat is a symlink to /bin/busybox and execution | |
514 | * of /bin/cat is requested, permission is checked for /bin/cat rather than | |
515 | * /bin/busybox and domainname which the current process will belong to after | |
516 | * execve() succeeds is calculated using /bin/cat rather than /bin/busybox . | |
517 | */ | |
847b173e | 518 | LIST_HEAD(tomoyo_alias_list); |
26a2a1c9 KT |
519 | |
520 | /** | |
521 | * tomoyo_update_alias_entry - Update "struct tomoyo_alias_entry" list. | |
522 | * | |
523 | * @original_name: The original program's real name. | |
524 | * @aliased_name: The symbolic program's symbolic link's name. | |
525 | * @is_delete: True if it is a delete request. | |
526 | * | |
527 | * Returns 0 on success, negative value otherwise. | |
fdb8ebb7 TH |
528 | * |
529 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
530 | */ |
531 | static int tomoyo_update_alias_entry(const char *original_name, | |
532 | const char *aliased_name, | |
533 | const bool is_delete) | |
534 | { | |
26a2a1c9 | 535 | struct tomoyo_alias_entry *ptr; |
9e4b50e9 | 536 | struct tomoyo_alias_entry e = { }; |
ca0b7df3 | 537 | int error = is_delete ? -ENOENT : -ENOMEM; |
26a2a1c9 | 538 | |
17080008 TH |
539 | if (!tomoyo_is_correct_path(original_name, 1, -1, -1) || |
540 | !tomoyo_is_correct_path(aliased_name, 1, -1, -1)) | |
26a2a1c9 | 541 | return -EINVAL; /* No patterns allowed. */ |
9e4b50e9 TH |
542 | e.original_name = tomoyo_get_name(original_name); |
543 | e.aliased_name = tomoyo_get_name(aliased_name); | |
544 | if (!e.original_name || !e.aliased_name) | |
ca0b7df3 | 545 | goto out; |
29282381 TH |
546 | if (mutex_lock_interruptible(&tomoyo_policy_lock)) |
547 | goto out; | |
fdb8ebb7 | 548 | list_for_each_entry_rcu(ptr, &tomoyo_alias_list, list) { |
9e4b50e9 | 549 | if (!tomoyo_is_same_alias_entry(ptr, &e)) |
26a2a1c9 KT |
550 | continue; |
551 | ptr->is_deleted = is_delete; | |
552 | error = 0; | |
ca0b7df3 | 553 | break; |
26a2a1c9 | 554 | } |
9e4b50e9 TH |
555 | if (!is_delete && error) { |
556 | struct tomoyo_alias_entry *entry = | |
557 | tomoyo_commit_ok(&e, sizeof(e)); | |
558 | if (entry) { | |
559 | list_add_tail_rcu(&entry->list, &tomoyo_alias_list); | |
560 | error = 0; | |
561 | } | |
26a2a1c9 | 562 | } |
f737d95d | 563 | mutex_unlock(&tomoyo_policy_lock); |
ca0b7df3 | 564 | out: |
9e4b50e9 TH |
565 | tomoyo_put_name(e.original_name); |
566 | tomoyo_put_name(e.aliased_name); | |
26a2a1c9 KT |
567 | return error; |
568 | } | |
569 | ||
570 | /** | |
571 | * tomoyo_read_alias_policy - Read "struct tomoyo_alias_entry" list. | |
572 | * | |
573 | * @head: Pointer to "struct tomoyo_io_buffer". | |
574 | * | |
575 | * Returns true on success, false otherwise. | |
fdb8ebb7 TH |
576 | * |
577 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
578 | */ |
579 | bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head) | |
580 | { | |
581 | struct list_head *pos; | |
582 | bool done = true; | |
583 | ||
26a2a1c9 KT |
584 | list_for_each_cookie(pos, head->read_var2, &tomoyo_alias_list) { |
585 | struct tomoyo_alias_entry *ptr; | |
586 | ||
587 | ptr = list_entry(pos, struct tomoyo_alias_entry, list); | |
588 | if (ptr->is_deleted) | |
589 | continue; | |
7d2948b1 TH |
590 | done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n", |
591 | ptr->original_name->name, | |
592 | ptr->aliased_name->name); | |
593 | if (!done) | |
26a2a1c9 | 594 | break; |
26a2a1c9 | 595 | } |
26a2a1c9 KT |
596 | return done; |
597 | } | |
598 | ||
599 | /** | |
600 | * tomoyo_write_alias_policy - Write "struct tomoyo_alias_entry" list. | |
601 | * | |
602 | * @data: String to parse. | |
603 | * @is_delete: True if it is a delete request. | |
604 | * | |
605 | * Returns 0 on success, negative value otherwise. | |
fdb8ebb7 TH |
606 | * |
607 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
608 | */ |
609 | int tomoyo_write_alias_policy(char *data, const bool is_delete) | |
610 | { | |
611 | char *cp = strchr(data, ' '); | |
612 | ||
613 | if (!cp) | |
614 | return -EINVAL; | |
615 | *cp++ = '\0'; | |
616 | return tomoyo_update_alias_entry(data, cp, is_delete); | |
617 | } | |
618 | ||
26a2a1c9 KT |
619 | /** |
620 | * tomoyo_find_or_assign_new_domain - Create a domain. | |
621 | * | |
622 | * @domainname: The name of domain. | |
623 | * @profile: Profile number to assign if the domain was newly created. | |
624 | * | |
625 | * Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise. | |
fdb8ebb7 TH |
626 | * |
627 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 KT |
628 | */ |
629 | struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * | |
630 | domainname, | |
631 | const u8 profile) | |
632 | { | |
ca0b7df3 | 633 | struct tomoyo_domain_info *entry; |
29282381 | 634 | struct tomoyo_domain_info *domain = NULL; |
26a2a1c9 | 635 | const struct tomoyo_path_info *saved_domainname; |
ca0b7df3 | 636 | bool found = false; |
26a2a1c9 | 637 | |
17080008 | 638 | if (!tomoyo_is_correct_domain(domainname)) |
ca0b7df3 | 639 | return NULL; |
bf24fb01 | 640 | saved_domainname = tomoyo_get_name(domainname); |
26a2a1c9 | 641 | if (!saved_domainname) |
ca0b7df3 | 642 | return NULL; |
4e5d6f7e | 643 | entry = kzalloc(sizeof(*entry), GFP_NOFS); |
29282381 TH |
644 | if (mutex_lock_interruptible(&tomoyo_policy_lock)) |
645 | goto out; | |
ca0b7df3 TH |
646 | list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) { |
647 | if (domain->is_deleted || | |
648 | tomoyo_pathcmp(saved_domainname, domain->domainname)) | |
649 | continue; | |
650 | found = true; | |
651 | break; | |
652 | } | |
653 | if (!found && tomoyo_memory_ok(entry)) { | |
654 | INIT_LIST_HEAD(&entry->acl_info_list); | |
655 | entry->domainname = saved_domainname; | |
bf24fb01 | 656 | saved_domainname = NULL; |
ca0b7df3 TH |
657 | entry->profile = profile; |
658 | list_add_tail_rcu(&entry->list, &tomoyo_domain_list); | |
659 | domain = entry; | |
660 | entry = NULL; | |
661 | found = true; | |
26a2a1c9 | 662 | } |
f737d95d | 663 | mutex_unlock(&tomoyo_policy_lock); |
29282381 | 664 | out: |
bf24fb01 | 665 | tomoyo_put_name(saved_domainname); |
ca0b7df3 TH |
666 | kfree(entry); |
667 | return found ? domain : NULL; | |
26a2a1c9 KT |
668 | } |
669 | ||
670 | /** | |
671 | * tomoyo_find_next_domain - Find a domain. | |
672 | * | |
56f8c9bc | 673 | * @bprm: Pointer to "struct linux_binprm". |
26a2a1c9 KT |
674 | * |
675 | * Returns 0 on success, negative value otherwise. | |
fdb8ebb7 TH |
676 | * |
677 | * Caller holds tomoyo_read_lock(). | |
26a2a1c9 | 678 | */ |
56f8c9bc | 679 | int tomoyo_find_next_domain(struct linux_binprm *bprm) |
26a2a1c9 KT |
680 | { |
681 | /* | |
682 | * This function assumes that the size of buffer returned by | |
683 | * tomoyo_realpath() = TOMOYO_MAX_PATHNAME_LEN. | |
684 | */ | |
4e5d6f7e | 685 | struct tomoyo_page_buffer *tmp = kzalloc(sizeof(*tmp), GFP_NOFS); |
26a2a1c9 KT |
686 | struct tomoyo_domain_info *old_domain = tomoyo_domain(); |
687 | struct tomoyo_domain_info *domain = NULL; | |
688 | const char *old_domain_name = old_domain->domainname->name; | |
689 | const char *original_name = bprm->filename; | |
690 | char *new_domain_name = NULL; | |
691 | char *real_program_name = NULL; | |
692 | char *symlink_program_name = NULL; | |
693 | const u8 mode = tomoyo_check_flags(old_domain, TOMOYO_MAC_FOR_FILE); | |
694 | const bool is_enforce = (mode == 3); | |
695 | int retval = -ENOMEM; | |
696 | struct tomoyo_path_info r; /* real name */ | |
697 | struct tomoyo_path_info s; /* symlink name */ | |
698 | struct tomoyo_path_info l; /* last name */ | |
699 | static bool initialized; | |
700 | ||
701 | if (!tmp) | |
702 | goto out; | |
703 | ||
704 | if (!initialized) { | |
705 | /* | |
706 | * Built-in initializers. This is needed because policies are | |
707 | * not loaded until starting /sbin/init. | |
708 | */ | |
709 | tomoyo_update_domain_initializer_entry(NULL, "/sbin/hotplug", | |
710 | false, false); | |
711 | tomoyo_update_domain_initializer_entry(NULL, "/sbin/modprobe", | |
712 | false, false); | |
713 | initialized = true; | |
714 | } | |
715 | ||
716 | /* Get tomoyo_realpath of program. */ | |
717 | retval = -ENOENT; | |
718 | /* I hope tomoyo_realpath() won't fail with -ENOMEM. */ | |
719 | real_program_name = tomoyo_realpath(original_name); | |
720 | if (!real_program_name) | |
721 | goto out; | |
722 | /* Get tomoyo_realpath of symbolic link. */ | |
723 | symlink_program_name = tomoyo_realpath_nofollow(original_name); | |
724 | if (!symlink_program_name) | |
725 | goto out; | |
726 | ||
727 | r.name = real_program_name; | |
728 | tomoyo_fill_path_info(&r); | |
729 | s.name = symlink_program_name; | |
730 | tomoyo_fill_path_info(&s); | |
731 | l.name = tomoyo_get_last_name(old_domain); | |
732 | tomoyo_fill_path_info(&l); | |
733 | ||
734 | /* Check 'alias' directive. */ | |
735 | if (tomoyo_pathcmp(&r, &s)) { | |
736 | struct tomoyo_alias_entry *ptr; | |
737 | /* Is this program allowed to be called via symbolic links? */ | |
fdb8ebb7 | 738 | list_for_each_entry_rcu(ptr, &tomoyo_alias_list, list) { |
26a2a1c9 KT |
739 | if (ptr->is_deleted || |
740 | tomoyo_pathcmp(&r, ptr->original_name) || | |
741 | tomoyo_pathcmp(&s, ptr->aliased_name)) | |
742 | continue; | |
743 | memset(real_program_name, 0, TOMOYO_MAX_PATHNAME_LEN); | |
744 | strncpy(real_program_name, ptr->aliased_name->name, | |
745 | TOMOYO_MAX_PATHNAME_LEN - 1); | |
746 | tomoyo_fill_path_info(&r); | |
747 | break; | |
748 | } | |
26a2a1c9 KT |
749 | } |
750 | ||
751 | /* Check execute permission. */ | |
bcb86975 | 752 | retval = tomoyo_check_exec_perm(old_domain, &r); |
26a2a1c9 KT |
753 | if (retval < 0) |
754 | goto out; | |
755 | ||
756 | new_domain_name = tmp->buffer; | |
757 | if (tomoyo_is_domain_initializer(old_domain->domainname, &r, &l)) { | |
758 | /* Transit to the child of tomoyo_kernel_domain domain. */ | |
759 | snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1, | |
760 | TOMOYO_ROOT_NAME " " "%s", real_program_name); | |
761 | } else if (old_domain == &tomoyo_kernel_domain && | |
762 | !tomoyo_policy_loaded) { | |
763 | /* | |
764 | * Needn't to transit from kernel domain before starting | |
765 | * /sbin/init. But transit from kernel domain if executing | |
766 | * initializers because they might start before /sbin/init. | |
767 | */ | |
768 | domain = old_domain; | |
769 | } else if (tomoyo_is_domain_keeper(old_domain->domainname, &r, &l)) { | |
770 | /* Keep current domain. */ | |
771 | domain = old_domain; | |
772 | } else { | |
773 | /* Normal domain transition. */ | |
774 | snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1, | |
775 | "%s %s", old_domain_name, real_program_name); | |
776 | } | |
777 | if (domain || strlen(new_domain_name) >= TOMOYO_MAX_PATHNAME_LEN) | |
778 | goto done; | |
26a2a1c9 | 779 | domain = tomoyo_find_domain(new_domain_name); |
26a2a1c9 KT |
780 | if (domain) |
781 | goto done; | |
782 | if (is_enforce) | |
783 | goto done; | |
784 | domain = tomoyo_find_or_assign_new_domain(new_domain_name, | |
785 | old_domain->profile); | |
786 | done: | |
787 | if (domain) | |
788 | goto out; | |
789 | printk(KERN_WARNING "TOMOYO-ERROR: Domain '%s' not defined.\n", | |
790 | new_domain_name); | |
791 | if (is_enforce) | |
792 | retval = -EPERM; | |
793 | else | |
ea13ddba | 794 | old_domain->transition_failed = true; |
26a2a1c9 | 795 | out: |
56f8c9bc TH |
796 | if (!domain) |
797 | domain = old_domain; | |
ec8e6a4e TH |
798 | /* Update reference count on "struct tomoyo_domain_info". */ |
799 | atomic_inc(&domain->users); | |
56f8c9bc | 800 | bprm->cred->security = domain; |
8e2d39a1 TH |
801 | kfree(real_program_name); |
802 | kfree(symlink_program_name); | |
803 | kfree(tmp); | |
26a2a1c9 KT |
804 | return retval; |
805 | } |