diff options
author | Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> | 2009-06-07 23:37:39 -0400 |
---|---|---|
committer | James Morris <jmorris@namei.org> | 2009-06-08 19:30:24 -0400 |
commit | c3fa109a5894077d1eaf8731ea741a15dd117b3c (patch) | |
tree | a3d5f58ea878868b48a1493055e6f2cb6dd3c9de /security/tomoyo/file.c | |
parent | 5bf1692f65c12a8aa359dc883468284ffc3c4587 (diff) |
TOMOYO: Add description of lists and structures.
This patch adds some descriptions of lists and structures.
This patch contains no code changes.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/tomoyo/file.c')
-rw-r--r-- | security/tomoyo/file.c | 121 |
1 files changed, 115 insertions, 6 deletions
diff --git a/security/tomoyo/file.c b/security/tomoyo/file.c index ab0cd3538510..5ae3a571559f 100644 --- a/security/tomoyo/file.c +++ b/security/tomoyo/file.c | |||
@@ -14,21 +14,50 @@ | |||
14 | #include "realpath.h" | 14 | #include "realpath.h" |
15 | #define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE]) | 15 | #define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE]) |
16 | 16 | ||
17 | /* Structure for "allow_read" keyword. */ | 17 | /* |
18 | * tomoyo_globally_readable_file_entry is a structure which is used for holding | ||
19 | * "allow_read" entries. | ||
20 | * It has following fields. | ||
21 | * | ||
22 | * (1) "list" which is linked to tomoyo_globally_readable_list . | ||
23 | * (2) "filename" is a pathname which is allowed to open(O_RDONLY). | ||
24 | * (3) "is_deleted" is a bool which is true if marked as deleted, false | ||
25 | * otherwise. | ||
26 | */ | ||
18 | struct tomoyo_globally_readable_file_entry { | 27 | struct tomoyo_globally_readable_file_entry { |
19 | struct list_head list; | 28 | struct list_head list; |
20 | const struct tomoyo_path_info *filename; | 29 | const struct tomoyo_path_info *filename; |
21 | bool is_deleted; | 30 | bool is_deleted; |
22 | }; | 31 | }; |
23 | 32 | ||
24 | /* Structure for "file_pattern" keyword. */ | 33 | /* |
34 | * tomoyo_pattern_entry is a structure which is used for holding | ||
35 | * "tomoyo_pattern_list" entries. | ||
36 | * It has following fields. | ||
37 | * | ||
38 | * (1) "list" which is linked to tomoyo_pattern_list . | ||
39 | * (2) "pattern" is a pathname pattern which is used for converting pathnames | ||
40 | * to pathname patterns during learning mode. | ||
41 | * (3) "is_deleted" is a bool which is true if marked as deleted, false | ||
42 | * otherwise. | ||
43 | */ | ||
25 | struct tomoyo_pattern_entry { | 44 | struct tomoyo_pattern_entry { |
26 | struct list_head list; | 45 | struct list_head list; |
27 | const struct tomoyo_path_info *pattern; | 46 | const struct tomoyo_path_info *pattern; |
28 | bool is_deleted; | 47 | bool is_deleted; |
29 | }; | 48 | }; |
30 | 49 | ||
31 | /* Structure for "deny_rewrite" keyword. */ | 50 | /* |
51 | * tomoyo_no_rewrite_entry is a structure which is used for holding | ||
52 | * "deny_rewrite" entries. | ||
53 | * It has following fields. | ||
54 | * | ||
55 | * (1) "list" which is linked to tomoyo_no_rewrite_list . | ||
56 | * (2) "pattern" is a pathname which is by default not permitted to modify | ||
57 | * already existing content. | ||
58 | * (3) "is_deleted" is a bool which is true if marked as deleted, false | ||
59 | * otherwise. | ||
60 | */ | ||
32 | struct tomoyo_no_rewrite_entry { | 61 | struct tomoyo_no_rewrite_entry { |
33 | struct list_head list; | 62 | struct list_head list; |
34 | const struct tomoyo_path_info *pattern; | 63 | const struct tomoyo_path_info *pattern; |
@@ -141,7 +170,31 @@ static int tomoyo_update_single_path_acl(const u8 type, const char *filename, | |||
141 | struct tomoyo_domain_info * | 170 | struct tomoyo_domain_info * |
142 | const domain, const bool is_delete); | 171 | const domain, const bool is_delete); |
143 | 172 | ||
144 | /* The list for "struct tomoyo_globally_readable_file_entry". */ | 173 | /* |
174 | * tomoyo_globally_readable_list is used for holding list of pathnames which | ||
175 | * are by default allowed to be open()ed for reading by any process. | ||
176 | * | ||
177 | * An entry is added by | ||
178 | * | ||
179 | * # echo 'allow_read /lib/libc-2.5.so' > \ | ||
180 | * /sys/kernel/security/tomoyo/exception_policy | ||
181 | * | ||
182 | * and is deleted by | ||
183 | * | ||
184 | * # echo 'delete allow_read /lib/libc-2.5.so' > \ | ||
185 | * /sys/kernel/security/tomoyo/exception_policy | ||
186 | * | ||
187 | * and all entries are retrieved by | ||
188 | * | ||
189 | * # grep ^allow_read /sys/kernel/security/tomoyo/exception_policy | ||
190 | * | ||
191 | * In the example above, any process is allowed to | ||
192 | * open("/lib/libc-2.5.so", O_RDONLY). | ||
193 | * One exception is, if the domain which current process belongs to is marked | ||
194 | * as "ignore_global_allow_read", current process can't do so unless explicitly | ||
195 | * given "allow_read /lib/libc-2.5.so" to the domain which current process | ||
196 | * belongs to. | ||
197 | */ | ||
145 | static LIST_HEAD(tomoyo_globally_readable_list); | 198 | static LIST_HEAD(tomoyo_globally_readable_list); |
146 | static DECLARE_RWSEM(tomoyo_globally_readable_list_lock); | 199 | static DECLARE_RWSEM(tomoyo_globally_readable_list_lock); |
147 | 200 | ||
@@ -256,7 +309,35 @@ bool tomoyo_read_globally_readable_policy(struct tomoyo_io_buffer *head) | |||
256 | return done; | 309 | return done; |
257 | } | 310 | } |
258 | 311 | ||
259 | /* The list for "struct tomoyo_pattern_entry". */ | 312 | /* tomoyo_pattern_list is used for holding list of pathnames which are used for |
313 | * converting pathnames to pathname patterns during learning mode. | ||
314 | * | ||
315 | * An entry is added by | ||
316 | * | ||
317 | * # echo 'file_pattern /proc/\$/mounts' > \ | ||
318 | * /sys/kernel/security/tomoyo/exception_policy | ||
319 | * | ||
320 | * and is deleted by | ||
321 | * | ||
322 | * # echo 'delete file_pattern /proc/\$/mounts' > \ | ||
323 | * /sys/kernel/security/tomoyo/exception_policy | ||
324 | * | ||
325 | * and all entries are retrieved by | ||
326 | * | ||
327 | * # grep ^file_pattern /sys/kernel/security/tomoyo/exception_policy | ||
328 | * | ||
329 | * In the example above, if a process which belongs to a domain which is in | ||
330 | * learning mode requested open("/proc/1/mounts", O_RDONLY), | ||
331 | * "allow_read /proc/\$/mounts" is automatically added to the domain which that | ||
332 | * process belongs to. | ||
333 | * | ||
334 | * It is not a desirable behavior that we have to use /proc/\$/ instead of | ||
335 | * /proc/self/ when current process needs to access only current process's | ||
336 | * information. As of now, LSM version of TOMOYO is using __d_path() for | ||
337 | * calculating pathname. Non LSM version of TOMOYO is using its own function | ||
338 | * which pretends as if /proc/self/ is not a symlink; so that we can forbid | ||
339 | * current process from accessing other process's information. | ||
340 | */ | ||
260 | static LIST_HEAD(tomoyo_pattern_list); | 341 | static LIST_HEAD(tomoyo_pattern_list); |
261 | static DECLARE_RWSEM(tomoyo_pattern_list_lock); | 342 | static DECLARE_RWSEM(tomoyo_pattern_list_lock); |
262 | 343 | ||
@@ -377,7 +458,35 @@ bool tomoyo_read_file_pattern(struct tomoyo_io_buffer *head) | |||
377 | return done; | 458 | return done; |
378 | } | 459 | } |
379 | 460 | ||
380 | /* The list for "struct tomoyo_no_rewrite_entry". */ | 461 | /* |
462 | * tomoyo_no_rewrite_list is used for holding list of pathnames which are by | ||
463 | * default forbidden to modify already written content of a file. | ||
464 | * | ||
465 | * An entry is added by | ||
466 | * | ||
467 | * # echo 'deny_rewrite /var/log/messages' > \ | ||
468 | * /sys/kernel/security/tomoyo/exception_policy | ||
469 | * | ||
470 | * and is deleted by | ||
471 | * | ||
472 | * # echo 'delete deny_rewrite /var/log/messages' > \ | ||
473 | * /sys/kernel/security/tomoyo/exception_policy | ||
474 | * | ||
475 | * and all entries are retrieved by | ||
476 | * | ||
477 | * # grep ^deny_rewrite /sys/kernel/security/tomoyo/exception_policy | ||
478 | * | ||
479 | * In the example above, if a process requested to rewrite /var/log/messages , | ||
480 | * the process can't rewrite unless the domain which that process belongs to | ||
481 | * has "allow_rewrite /var/log/messages" entry. | ||
482 | * | ||
483 | * It is not a desirable behavior that we have to add "\040(deleted)" suffix | ||
484 | * when we want to allow rewriting already unlink()ed file. As of now, | ||
485 | * LSM version of TOMOYO is using __d_path() for calculating pathname. | ||
486 | * Non LSM version of TOMOYO is using its own function which doesn't append | ||
487 | * " (deleted)" suffix if the file is already unlink()ed; so that we don't | ||
488 | * need to worry whether the file is already unlink()ed or not. | ||
489 | */ | ||
381 | static LIST_HEAD(tomoyo_no_rewrite_list); | 490 | static LIST_HEAD(tomoyo_no_rewrite_list); |
382 | static DECLARE_RWSEM(tomoyo_no_rewrite_list_lock); | 491 | static DECLARE_RWSEM(tomoyo_no_rewrite_list_lock); |
383 | 492 | ||