1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * security/tomoyo/file.c
4 *
5 * Copyright (C) 2005-2011 NTT DATA CORPORATION
6 */
7
8 #include "common.h"
9 #include <linux/slab.h>
10
11 /*
12 * Mapping table from "enum tomoyo_path_acl_index" to "enum tomoyo_mac_index".
13 */
14 static const u8 tomoyo_p2mac[TOMOYO_MAX_PATH_OPERATION] = {
15 [TOMOYO_TYPE_EXECUTE] = TOMOYO_MAC_FILE_EXECUTE,
16 [TOMOYO_TYPE_READ] = TOMOYO_MAC_FILE_OPEN,
17 [TOMOYO_TYPE_WRITE] = TOMOYO_MAC_FILE_OPEN,
18 [TOMOYO_TYPE_APPEND] = TOMOYO_MAC_FILE_OPEN,
19 [TOMOYO_TYPE_UNLINK] = TOMOYO_MAC_FILE_UNLINK,
20 [TOMOYO_TYPE_GETATTR] = TOMOYO_MAC_FILE_GETATTR,
21 [TOMOYO_TYPE_RMDIR] = TOMOYO_MAC_FILE_RMDIR,
22 [TOMOYO_TYPE_TRUNCATE] = TOMOYO_MAC_FILE_TRUNCATE,
23 [TOMOYO_TYPE_SYMLINK] = TOMOYO_MAC_FILE_SYMLINK,
24 [TOMOYO_TYPE_CHROOT] = TOMOYO_MAC_FILE_CHROOT,
25 [TOMOYO_TYPE_UMOUNT] = TOMOYO_MAC_FILE_UMOUNT,
26 };
27
28 /*
29 * Mapping table from "enum tomoyo_mkdev_acl_index" to "enum tomoyo_mac_index".
30 */
31 const u8 tomoyo_pnnn2mac[TOMOYO_MAX_MKDEV_OPERATION] = {
32 [TOMOYO_TYPE_MKBLOCK] = TOMOYO_MAC_FILE_MKBLOCK,
33 [TOMOYO_TYPE_MKCHAR] = TOMOYO_MAC_FILE_MKCHAR,
34 };
35
36 /*
37 * Mapping table from "enum tomoyo_path2_acl_index" to "enum tomoyo_mac_index".
38 */
39 const u8 tomoyo_pp2mac[TOMOYO_MAX_PATH2_OPERATION] = {
40 [TOMOYO_TYPE_LINK] = TOMOYO_MAC_FILE_LINK,
41 [TOMOYO_TYPE_RENAME] = TOMOYO_MAC_FILE_RENAME,
42 [TOMOYO_TYPE_PIVOT_ROOT] = TOMOYO_MAC_FILE_PIVOT_ROOT,
43 };
44
45 /*
46 * Mapping table from "enum tomoyo_path_number_acl_index" to
47 * "enum tomoyo_mac_index".
48 */
49 const u8 tomoyo_pn2mac[TOMOYO_MAX_PATH_NUMBER_OPERATION] = {
50 [TOMOYO_TYPE_CREATE] = TOMOYO_MAC_FILE_CREATE,
51 [TOMOYO_TYPE_MKDIR] = TOMOYO_MAC_FILE_MKDIR,
52 [TOMOYO_TYPE_MKFIFO] = TOMOYO_MAC_FILE_MKFIFO,
53 [TOMOYO_TYPE_MKSOCK] = TOMOYO_MAC_FILE_MKSOCK,
54 [TOMOYO_TYPE_IOCTL] = TOMOYO_MAC_FILE_IOCTL,
55 [TOMOYO_TYPE_CHMOD] = TOMOYO_MAC_FILE_CHMOD,
56 [TOMOYO_TYPE_CHOWN] = TOMOYO_MAC_FILE_CHOWN,
57 [TOMOYO_TYPE_CHGRP] = TOMOYO_MAC_FILE_CHGRP,
58 };
59
60 /**
61 * tomoyo_put_name_union - Drop reference on "struct tomoyo_name_union".
62 *
63 * @ptr: Pointer to "struct tomoyo_name_union".
64 *
65 * Returns nothing.
66 */
tomoyo_put_name_union(struct tomoyo_name_union * ptr)67 void tomoyo_put_name_union(struct tomoyo_name_union *ptr)
68 {
69 tomoyo_put_group(ptr->group);
70 tomoyo_put_name(ptr->filename);
71 }
72
73 /**
74 * tomoyo_compare_name_union - Check whether a name matches "struct tomoyo_name_union" or not.
75 *
76 * @name: Pointer to "struct tomoyo_path_info".
77 * @ptr: Pointer to "struct tomoyo_name_union".
78 *
79 * Returns "struct tomoyo_path_info" if @name matches @ptr, NULL otherwise.
80 */
81 const struct tomoyo_path_info *
tomoyo_compare_name_union(const struct tomoyo_path_info * name,const struct tomoyo_name_union * ptr)82 tomoyo_compare_name_union(const struct tomoyo_path_info *name,
83 const struct tomoyo_name_union *ptr)
84 {
85 if (ptr->group)
86 return tomoyo_path_matches_group(name, ptr->group);
87 if (tomoyo_path_matches_pattern(name, ptr->filename))
88 return ptr->filename;
89 return NULL;
90 }
91
92 /**
93 * tomoyo_put_number_union - Drop reference on "struct tomoyo_number_union".
94 *
95 * @ptr: Pointer to "struct tomoyo_number_union".
96 *
97 * Returns nothing.
98 */
tomoyo_put_number_union(struct tomoyo_number_union * ptr)99 void tomoyo_put_number_union(struct tomoyo_number_union *ptr)
100 {
101 tomoyo_put_group(ptr->group);
102 }
103
104 /**
105 * tomoyo_compare_number_union - Check whether a value matches "struct tomoyo_number_union" or not.
106 *
107 * @value: Number to check.
108 * @ptr: Pointer to "struct tomoyo_number_union".
109 *
110 * Returns true if @value matches @ptr, false otherwise.
111 */
tomoyo_compare_number_union(const unsigned long value,const struct tomoyo_number_union * ptr)112 bool tomoyo_compare_number_union(const unsigned long value,
113 const struct tomoyo_number_union *ptr)
114 {
115 if (ptr->group)
116 return tomoyo_number_matches_group(value, value, ptr->group);
117 return value >= ptr->values[0] && value <= ptr->values[1];
118 }
119
120 /**
121 * tomoyo_add_slash - Add trailing '/' if needed.
122 *
123 * @buf: Pointer to "struct tomoyo_path_info".
124 *
125 * Returns nothing.
126 *
127 * @buf must be generated by tomoyo_encode() because this function does not
128 * allocate memory for adding '/'.
129 */
tomoyo_add_slash(struct tomoyo_path_info * buf)130 static void tomoyo_add_slash(struct tomoyo_path_info *buf)
131 {
132 if (buf->is_dir)
133 return;
134 /*
135 * This is OK because tomoyo_encode() reserves space for appending "/".
136 */
137 strcat((char *) buf->name, "/");
138 tomoyo_fill_path_info(buf);
139 }
140
141 /**
142 * tomoyo_get_realpath - Get realpath.
143 *
144 * @buf: Pointer to "struct tomoyo_path_info".
145 * @path: Pointer to "struct path".
146 *
147 * Returns true on success, false otherwise.
148 */
tomoyo_get_realpath(struct tomoyo_path_info * buf,const struct path * path)149 static bool tomoyo_get_realpath(struct tomoyo_path_info *buf, const struct path *path)
150 {
151 buf->name = tomoyo_realpath_from_path(path);
152 if (buf->name) {
153 tomoyo_fill_path_info(buf);
154 return true;
155 }
156 return false;
157 }
158
159 /**
160 * tomoyo_audit_path_log - Audit path request log.
161 *
162 * @r: Pointer to "struct tomoyo_request_info".
163 *
164 * Returns 0 on success, negative value otherwise.
165 */
tomoyo_audit_path_log(struct tomoyo_request_info * r)166 static int tomoyo_audit_path_log(struct tomoyo_request_info *r)
167 {
168 return tomoyo_supervisor(r, "file %s %s\n", tomoyo_path_keyword
169 [r->param.path.operation],
170 r->param.path.filename->name);
171 }
172
173 /**
174 * tomoyo_audit_path2_log - Audit path/path request log.
175 *
176 * @r: Pointer to "struct tomoyo_request_info".
177 *
178 * Returns 0 on success, negative value otherwise.
179 */
tomoyo_audit_path2_log(struct tomoyo_request_info * r)180 static int tomoyo_audit_path2_log(struct tomoyo_request_info *r)
181 {
182 return tomoyo_supervisor(r, "file %s %s %s\n", tomoyo_mac_keywords
183 [tomoyo_pp2mac[r->param.path2.operation]],
184 r->param.path2.filename1->name,
185 r->param.path2.filename2->name);
186 }
187
188 /**
189 * tomoyo_audit_mkdev_log - Audit path/number/number/number request log.
190 *
191 * @r: Pointer to "struct tomoyo_request_info".
192 *
193 * Returns 0 on success, negative value otherwise.
194 */
tomoyo_audit_mkdev_log(struct tomoyo_request_info * r)195 static int tomoyo_audit_mkdev_log(struct tomoyo_request_info *r)
196 {
197 return tomoyo_supervisor(r, "file %s %s 0%o %u %u\n",
198 tomoyo_mac_keywords
199 [tomoyo_pnnn2mac[r->param.mkdev.operation]],
200 r->param.mkdev.filename->name,
201 r->param.mkdev.mode, r->param.mkdev.major,
202 r->param.mkdev.minor);
203 }
204
205 /**
206 * tomoyo_audit_path_number_log - Audit path/number request log.
207 *
208 * @r: Pointer to "struct tomoyo_request_info".
209 *
210 * Returns 0 on success, negative value otherwise.
211 */
tomoyo_audit_path_number_log(struct tomoyo_request_info * r)212 static int tomoyo_audit_path_number_log(struct tomoyo_request_info *r)
213 {
214 const u8 type = r->param.path_number.operation;
215 u8 radix;
216 char buffer[64];
217
218 switch (type) {
219 case TOMOYO_TYPE_CREATE:
220 case TOMOYO_TYPE_MKDIR:
221 case TOMOYO_TYPE_MKFIFO:
222 case TOMOYO_TYPE_MKSOCK:
223 case TOMOYO_TYPE_CHMOD:
224 radix = TOMOYO_VALUE_TYPE_OCTAL;
225 break;
226 case TOMOYO_TYPE_IOCTL:
227 radix = TOMOYO_VALUE_TYPE_HEXADECIMAL;
228 break;
229 default:
230 radix = TOMOYO_VALUE_TYPE_DECIMAL;
231 break;
232 }
233 tomoyo_print_ulong(buffer, sizeof(buffer), r->param.path_number.number,
234 radix);
235 return tomoyo_supervisor(r, "file %s %s %s\n", tomoyo_mac_keywords
236 [tomoyo_pn2mac[type]],
237 r->param.path_number.filename->name, buffer);
238 }
239
240 /**
241 * tomoyo_check_path_acl - Check permission for path operation.
242 *
243 * @r: Pointer to "struct tomoyo_request_info".
244 * @ptr: Pointer to "struct tomoyo_acl_info".
245 *
246 * Returns true if granted, false otherwise.
247 *
248 * To be able to use wildcard for domain transition, this function sets
249 * matching entry on success. Since the caller holds tomoyo_read_lock(),
250 * it is safe to set matching entry.
251 */
tomoyo_check_path_acl(struct tomoyo_request_info * r,const struct tomoyo_acl_info * ptr)252 static bool tomoyo_check_path_acl(struct tomoyo_request_info *r,
253 const struct tomoyo_acl_info *ptr)
254 {
255 const struct tomoyo_path_acl *acl = container_of(ptr, typeof(*acl),
256 head);
257
258 if (acl->perm & (1 << r->param.path.operation)) {
259 r->param.path.matched_path =
260 tomoyo_compare_name_union(r->param.path.filename,
261 &acl->name);
262 return r->param.path.matched_path != NULL;
263 }
264 return false;
265 }
266
267 /**
268 * tomoyo_check_path_number_acl - Check permission for path number operation.
269 *
270 * @r: Pointer to "struct tomoyo_request_info".
271 * @ptr: Pointer to "struct tomoyo_acl_info".
272 *
273 * Returns true if granted, false otherwise.
274 */
tomoyo_check_path_number_acl(struct tomoyo_request_info * r,const struct tomoyo_acl_info * ptr)275 static bool tomoyo_check_path_number_acl(struct tomoyo_request_info *r,
276 const struct tomoyo_acl_info *ptr)
277 {
278 const struct tomoyo_path_number_acl *acl =
279 container_of(ptr, typeof(*acl), head);
280
281 return (acl->perm & (1 << r->param.path_number.operation)) &&
282 tomoyo_compare_number_union(r->param.path_number.number,
283 &acl->number) &&
284 tomoyo_compare_name_union(r->param.path_number.filename,
285 &acl->name);
286 }
287
288 /**
289 * tomoyo_check_path2_acl - Check permission for path path operation.
290 *
291 * @r: Pointer to "struct tomoyo_request_info".
292 * @ptr: Pointer to "struct tomoyo_acl_info".
293 *
294 * Returns true if granted, false otherwise.
295 */
tomoyo_check_path2_acl(struct tomoyo_request_info * r,const struct tomoyo_acl_info * ptr)296 static bool tomoyo_check_path2_acl(struct tomoyo_request_info *r,
297 const struct tomoyo_acl_info *ptr)
298 {
299 const struct tomoyo_path2_acl *acl =
300 container_of(ptr, typeof(*acl), head);
301
302 return (acl->perm & (1 << r->param.path2.operation)) &&
303 tomoyo_compare_name_union(r->param.path2.filename1, &acl->name1)
304 && tomoyo_compare_name_union(r->param.path2.filename2,
305 &acl->name2);
306 }
307
308 /**
309 * tomoyo_check_mkdev_acl - Check permission for path number number number operation.
310 *
311 * @r: Pointer to "struct tomoyo_request_info".
312 * @ptr: Pointer to "struct tomoyo_acl_info".
313 *
314 * Returns true if granted, false otherwise.
315 */
tomoyo_check_mkdev_acl(struct tomoyo_request_info * r,const struct tomoyo_acl_info * ptr)316 static bool tomoyo_check_mkdev_acl(struct tomoyo_request_info *r,
317 const struct tomoyo_acl_info *ptr)
318 {
319 const struct tomoyo_mkdev_acl *acl =
320 container_of(ptr, typeof(*acl), head);
321
322 return (acl->perm & (1 << r->param.mkdev.operation)) &&
323 tomoyo_compare_number_union(r->param.mkdev.mode,
324 &acl->mode) &&
325 tomoyo_compare_number_union(r->param.mkdev.major,
326 &acl->major) &&
327 tomoyo_compare_number_union(r->param.mkdev.minor,
328 &acl->minor) &&
329 tomoyo_compare_name_union(r->param.mkdev.filename,
330 &acl->name);
331 }
332
333 /**
334 * tomoyo_same_path_acl - Check for duplicated "struct tomoyo_path_acl" entry.
335 *
336 * @a: Pointer to "struct tomoyo_acl_info".
337 * @b: Pointer to "struct tomoyo_acl_info".
338 *
339 * Returns true if @a == @b except permission bits, false otherwise.
340 */
tomoyo_same_path_acl(const struct tomoyo_acl_info * a,const struct tomoyo_acl_info * b)341 static bool tomoyo_same_path_acl(const struct tomoyo_acl_info *a,
342 const struct tomoyo_acl_info *b)
343 {
344 const struct tomoyo_path_acl *p1 = container_of(a, typeof(*p1), head);
345 const struct tomoyo_path_acl *p2 = container_of(b, typeof(*p2), head);
346
347 return tomoyo_same_name_union(&p1->name, &p2->name);
348 }
349
350 /**
351 * tomoyo_merge_path_acl - Merge duplicated "struct tomoyo_path_acl" entry.
352 *
353 * @a: Pointer to "struct tomoyo_acl_info".
354 * @b: Pointer to "struct tomoyo_acl_info".
355 * @is_delete: True for @a &= ~@b, false for @a |= @b.
356 *
357 * Returns true if @a is empty, false otherwise.
358 */
tomoyo_merge_path_acl(struct tomoyo_acl_info * a,struct tomoyo_acl_info * b,const bool is_delete)359 static bool tomoyo_merge_path_acl(struct tomoyo_acl_info *a,
360 struct tomoyo_acl_info *b,
361 const bool is_delete)
362 {
363 u16 * const a_perm = &container_of(a, struct tomoyo_path_acl, head)
364 ->perm;
365 u16 perm = READ_ONCE(*a_perm);
366 const u16 b_perm = container_of(b, struct tomoyo_path_acl, head)->perm;
367
368 if (is_delete)
369 perm &= ~b_perm;
370 else
371 perm |= b_perm;
372 WRITE_ONCE(*a_perm, perm);
373 return !perm;
374 }
375
376 /**
377 * tomoyo_update_path_acl - Update "struct tomoyo_path_acl" list.
378 *
379 * @perm: Permission.
380 * @param: Pointer to "struct tomoyo_acl_param".
381 *
382 * Returns 0 on success, negative value otherwise.
383 *
384 * Caller holds tomoyo_read_lock().
385 */
tomoyo_update_path_acl(const u16 perm,struct tomoyo_acl_param * param)386 static int tomoyo_update_path_acl(const u16 perm,
387 struct tomoyo_acl_param *param)
388 {
389 struct tomoyo_path_acl e = {
390 .head.type = TOMOYO_TYPE_PATH_ACL,
391 .perm = perm
392 };
393 int error;
394
395 if (!tomoyo_parse_name_union(param, &e.name))
396 error = -EINVAL;
397 else
398 error = tomoyo_update_domain(&e.head, sizeof(e), param,
399 tomoyo_same_path_acl,
400 tomoyo_merge_path_acl);
401 tomoyo_put_name_union(&e.name);
402 return error;
403 }
404
405 /**
406 * tomoyo_same_mkdev_acl - Check for duplicated "struct tomoyo_mkdev_acl" entry.
407 *
408 * @a: Pointer to "struct tomoyo_acl_info".
409 * @b: Pointer to "struct tomoyo_acl_info".
410 *
411 * Returns true if @a == @b except permission bits, false otherwise.
412 */
tomoyo_same_mkdev_acl(const struct tomoyo_acl_info * a,const struct tomoyo_acl_info * b)413 static bool tomoyo_same_mkdev_acl(const struct tomoyo_acl_info *a,
414 const struct tomoyo_acl_info *b)
415 {
416 const struct tomoyo_mkdev_acl *p1 = container_of(a, typeof(*p1), head);
417 const struct tomoyo_mkdev_acl *p2 = container_of(b, typeof(*p2), head);
418
419 return tomoyo_same_name_union(&p1->name, &p2->name) &&
420 tomoyo_same_number_union(&p1->mode, &p2->mode) &&
421 tomoyo_same_number_union(&p1->major, &p2->major) &&
422 tomoyo_same_number_union(&p1->minor, &p2->minor);
423 }
424
425 /**
426 * tomoyo_merge_mkdev_acl - Merge duplicated "struct tomoyo_mkdev_acl" entry.
427 *
428 * @a: Pointer to "struct tomoyo_acl_info".
429 * @b: Pointer to "struct tomoyo_acl_info".
430 * @is_delete: True for @a &= ~@b, false for @a |= @b.
431 *
432 * Returns true if @a is empty, false otherwise.
433 */
tomoyo_merge_mkdev_acl(struct tomoyo_acl_info * a,struct tomoyo_acl_info * b,const bool is_delete)434 static bool tomoyo_merge_mkdev_acl(struct tomoyo_acl_info *a,
435 struct tomoyo_acl_info *b,
436 const bool is_delete)
437 {
438 u8 *const a_perm = &container_of(a, struct tomoyo_mkdev_acl,
439 head)->perm;
440 u8 perm = READ_ONCE(*a_perm);
441 const u8 b_perm = container_of(b, struct tomoyo_mkdev_acl, head)
442 ->perm;
443
444 if (is_delete)
445 perm &= ~b_perm;
446 else
447 perm |= b_perm;
448 WRITE_ONCE(*a_perm, perm);
449 return !perm;
450 }
451
452 /**
453 * tomoyo_update_mkdev_acl - Update "struct tomoyo_mkdev_acl" list.
454 *
455 * @perm: Permission.
456 * @param: Pointer to "struct tomoyo_acl_param".
457 *
458 * Returns 0 on success, negative value otherwise.
459 *
460 * Caller holds tomoyo_read_lock().
461 */
tomoyo_update_mkdev_acl(const u8 perm,struct tomoyo_acl_param * param)462 static int tomoyo_update_mkdev_acl(const u8 perm,
463 struct tomoyo_acl_param *param)
464 {
465 struct tomoyo_mkdev_acl e = {
466 .head.type = TOMOYO_TYPE_MKDEV_ACL,
467 .perm = perm
468 };
469 int error;
470
471 if (!tomoyo_parse_name_union(param, &e.name) ||
472 !tomoyo_parse_number_union(param, &e.mode) ||
473 !tomoyo_parse_number_union(param, &e.major) ||
474 !tomoyo_parse_number_union(param, &e.minor))
475 error = -EINVAL;
476 else
477 error = tomoyo_update_domain(&e.head, sizeof(e), param,
478 tomoyo_same_mkdev_acl,
479 tomoyo_merge_mkdev_acl);
480 tomoyo_put_name_union(&e.name);
481 tomoyo_put_number_union(&e.mode);
482 tomoyo_put_number_union(&e.major);
483 tomoyo_put_number_union(&e.minor);
484 return error;
485 }
486
487 /**
488 * tomoyo_same_path2_acl - Check for duplicated "struct tomoyo_path2_acl" entry.
489 *
490 * @a: Pointer to "struct tomoyo_acl_info".
491 * @b: Pointer to "struct tomoyo_acl_info".
492 *
493 * Returns true if @a == @b except permission bits, false otherwise.
494 */
tomoyo_same_path2_acl(const struct tomoyo_acl_info * a,const struct tomoyo_acl_info * b)495 static bool tomoyo_same_path2_acl(const struct tomoyo_acl_info *a,
496 const struct tomoyo_acl_info *b)
497 {
498 const struct tomoyo_path2_acl *p1 = container_of(a, typeof(*p1), head);
499 const struct tomoyo_path2_acl *p2 = container_of(b, typeof(*p2), head);
500
501 return tomoyo_same_name_union(&p1->name1, &p2->name1) &&
502 tomoyo_same_name_union(&p1->name2, &p2->name2);
503 }
504
505 /**
506 * tomoyo_merge_path2_acl - Merge duplicated "struct tomoyo_path2_acl" entry.
507 *
508 * @a: Pointer to "struct tomoyo_acl_info".
509 * @b: Pointer to "struct tomoyo_acl_info".
510 * @is_delete: True for @a &= ~@b, false for @a |= @b.
511 *
512 * Returns true if @a is empty, false otherwise.
513 */
tomoyo_merge_path2_acl(struct tomoyo_acl_info * a,struct tomoyo_acl_info * b,const bool is_delete)514 static bool tomoyo_merge_path2_acl(struct tomoyo_acl_info *a,
515 struct tomoyo_acl_info *b,
516 const bool is_delete)
517 {
518 u8 * const a_perm = &container_of(a, struct tomoyo_path2_acl, head)
519 ->perm;
520 u8 perm = READ_ONCE(*a_perm);
521 const u8 b_perm = container_of(b, struct tomoyo_path2_acl, head)->perm;
522
523 if (is_delete)
524 perm &= ~b_perm;
525 else
526 perm |= b_perm;
527 WRITE_ONCE(*a_perm, perm);
528 return !perm;
529 }
530
531 /**
532 * tomoyo_update_path2_acl - Update "struct tomoyo_path2_acl" list.
533 *
534 * @perm: Permission.
535 * @param: Pointer to "struct tomoyo_acl_param".
536 *
537 * Returns 0 on success, negative value otherwise.
538 *
539 * Caller holds tomoyo_read_lock().
540 */
tomoyo_update_path2_acl(const u8 perm,struct tomoyo_acl_param * param)541 static int tomoyo_update_path2_acl(const u8 perm,
542 struct tomoyo_acl_param *param)
543 {
544 struct tomoyo_path2_acl e = {
545 .head.type = TOMOYO_TYPE_PATH2_ACL,
546 .perm = perm
547 };
548 int error;
549
550 if (!tomoyo_parse_name_union(param, &e.name1) ||
551 !tomoyo_parse_name_union(param, &e.name2))
552 error = -EINVAL;
553 else
554 error = tomoyo_update_domain(&e.head, sizeof(e), param,
555 tomoyo_same_path2_acl,
556 tomoyo_merge_path2_acl);
557 tomoyo_put_name_union(&e.name1);
558 tomoyo_put_name_union(&e.name2);
559 return error;
560 }
561
562 /**
563 * tomoyo_path_permission - Check permission for single path operation.
564 *
565 * @r: Pointer to "struct tomoyo_request_info".
566 * @operation: Type of operation.
567 * @filename: Filename to check.
568 *
569 * Returns 0 on success, negative value otherwise.
570 *
571 * Caller holds tomoyo_read_lock().
572 */
tomoyo_path_permission(struct tomoyo_request_info * r,u8 operation,const struct tomoyo_path_info * filename)573 static int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
574 const struct tomoyo_path_info *filename)
575 {
576 int error;
577
578 r->type = tomoyo_p2mac[operation];
579 r->mode = tomoyo_get_mode(r->domain->ns, r->profile, r->type);
580 if (r->mode == TOMOYO_CONFIG_DISABLED)
581 return 0;
582 r->param_type = TOMOYO_TYPE_PATH_ACL;
583 r->param.path.filename = filename;
584 r->param.path.operation = operation;
585 do {
586 tomoyo_check_acl(r, tomoyo_check_path_acl);
587 error = tomoyo_audit_path_log(r);
588 } while (error == TOMOYO_RETRY_REQUEST);
589 return error;
590 }
591
592 /**
593 * tomoyo_execute_permission - Check permission for execute operation.
594 *
595 * @r: Pointer to "struct tomoyo_request_info".
596 * @filename: Filename to check.
597 *
598 * Returns 0 on success, negative value otherwise.
599 *
600 * Caller holds tomoyo_read_lock().
601 */
tomoyo_execute_permission(struct tomoyo_request_info * r,const struct tomoyo_path_info * filename)602 int tomoyo_execute_permission(struct tomoyo_request_info *r,
603 const struct tomoyo_path_info *filename)
604 {
605 /*
606 * Unlike other permission checks, this check is done regardless of
607 * profile mode settings in order to check for domain transition
608 * preference.
609 */
610 r->type = TOMOYO_MAC_FILE_EXECUTE;
611 r->mode = tomoyo_get_mode(r->domain->ns, r->profile, r->type);
612 r->param_type = TOMOYO_TYPE_PATH_ACL;
613 r->param.path.filename = filename;
614 r->param.path.operation = TOMOYO_TYPE_EXECUTE;
615 tomoyo_check_acl(r, tomoyo_check_path_acl);
616 r->ee->transition = r->matched_acl && r->matched_acl->cond ?
617 r->matched_acl->cond->transit : NULL;
618 if (r->mode != TOMOYO_CONFIG_DISABLED)
619 return tomoyo_audit_path_log(r);
620 return 0;
621 }
622
623 /**
624 * tomoyo_same_path_number_acl - Check for duplicated "struct tomoyo_path_number_acl" entry.
625 *
626 * @a: Pointer to "struct tomoyo_acl_info".
627 * @b: Pointer to "struct tomoyo_acl_info".
628 *
629 * Returns true if @a == @b except permission bits, false otherwise.
630 */
tomoyo_same_path_number_acl(const struct tomoyo_acl_info * a,const struct tomoyo_acl_info * b)631 static bool tomoyo_same_path_number_acl(const struct tomoyo_acl_info *a,
632 const struct tomoyo_acl_info *b)
633 {
634 const struct tomoyo_path_number_acl *p1 = container_of(a, typeof(*p1),
635 head);
636 const struct tomoyo_path_number_acl *p2 = container_of(b, typeof(*p2),
637 head);
638
639 return tomoyo_same_name_union(&p1->name, &p2->name) &&
640 tomoyo_same_number_union(&p1->number, &p2->number);
641 }
642
643 /**
644 * tomoyo_merge_path_number_acl - Merge duplicated "struct tomoyo_path_number_acl" entry.
645 *
646 * @a: Pointer to "struct tomoyo_acl_info".
647 * @b: Pointer to "struct tomoyo_acl_info".
648 * @is_delete: True for @a &= ~@b, false for @a |= @b.
649 *
650 * Returns true if @a is empty, false otherwise.
651 */
tomoyo_merge_path_number_acl(struct tomoyo_acl_info * a,struct tomoyo_acl_info * b,const bool is_delete)652 static bool tomoyo_merge_path_number_acl(struct tomoyo_acl_info *a,
653 struct tomoyo_acl_info *b,
654 const bool is_delete)
655 {
656 u8 * const a_perm = &container_of(a, struct tomoyo_path_number_acl,
657 head)->perm;
658 u8 perm = READ_ONCE(*a_perm);
659 const u8 b_perm = container_of(b, struct tomoyo_path_number_acl, head)
660 ->perm;
661
662 if (is_delete)
663 perm &= ~b_perm;
664 else
665 perm |= b_perm;
666 WRITE_ONCE(*a_perm, perm);
667 return !perm;
668 }
669
670 /**
671 * tomoyo_update_path_number_acl - Update ioctl/chmod/chown/chgrp ACL.
672 *
673 * @perm: Permission.
674 * @param: Pointer to "struct tomoyo_acl_param".
675 *
676 * Returns 0 on success, negative value otherwise.
677 */
tomoyo_update_path_number_acl(const u8 perm,struct tomoyo_acl_param * param)678 static int tomoyo_update_path_number_acl(const u8 perm,
679 struct tomoyo_acl_param *param)
680 {
681 struct tomoyo_path_number_acl e = {
682 .head.type = TOMOYO_TYPE_PATH_NUMBER_ACL,
683 .perm = perm
684 };
685 int error;
686
687 if (!tomoyo_parse_name_union(param, &e.name) ||
688 !tomoyo_parse_number_union(param, &e.number))
689 error = -EINVAL;
690 else
691 error = tomoyo_update_domain(&e.head, sizeof(e), param,
692 tomoyo_same_path_number_acl,
693 tomoyo_merge_path_number_acl);
694 tomoyo_put_name_union(&e.name);
695 tomoyo_put_number_union(&e.number);
696 return error;
697 }
698
699 /**
700 * tomoyo_path_number_perm - Check permission for "create", "mkdir", "mkfifo", "mksock", "ioctl", "chmod", "chown", "chgrp".
701 *
702 * @type: Type of operation.
703 * @path: Pointer to "struct path".
704 * @number: Number.
705 *
706 * Returns 0 on success, negative value otherwise.
707 */
tomoyo_path_number_perm(const u8 type,const struct path * path,unsigned long number)708 int tomoyo_path_number_perm(const u8 type, const struct path *path,
709 unsigned long number)
710 {
711 struct tomoyo_request_info r;
712 struct tomoyo_obj_info obj = {
713 .path1 = { .mnt = path->mnt, .dentry = path->dentry },
714 };
715 int error = -ENOMEM;
716 struct tomoyo_path_info buf;
717 int idx;
718
719 if (tomoyo_init_request_info(&r, NULL, tomoyo_pn2mac[type])
720 == TOMOYO_CONFIG_DISABLED)
721 return 0;
722 idx = tomoyo_read_lock();
723 if (!tomoyo_get_realpath(&buf, path))
724 goto out;
725 r.obj = &obj;
726 if (type == TOMOYO_TYPE_MKDIR)
727 tomoyo_add_slash(&buf);
728 r.param_type = TOMOYO_TYPE_PATH_NUMBER_ACL;
729 r.param.path_number.operation = type;
730 r.param.path_number.filename = &buf;
731 r.param.path_number.number = number;
732 do {
733 tomoyo_check_acl(&r, tomoyo_check_path_number_acl);
734 error = tomoyo_audit_path_number_log(&r);
735 } while (error == TOMOYO_RETRY_REQUEST);
736 kfree(buf.name);
737 out:
738 tomoyo_read_unlock(idx);
739 if (r.mode != TOMOYO_CONFIG_ENFORCING)
740 error = 0;
741 return error;
742 }
743
744 /**
745 * tomoyo_check_open_permission - Check permission for "read" and "write".
746 *
747 * @domain: Pointer to "struct tomoyo_domain_info".
748 * @path: Pointer to "struct path".
749 * @flag: Flags for open().
750 *
751 * Returns 0 on success, negative value otherwise.
752 */
tomoyo_check_open_permission(struct tomoyo_domain_info * domain,const struct path * path,const int flag)753 int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
754 const struct path *path, const int flag)
755 {
756 const u8 acc_mode = ACC_MODE(flag);
757 int error = 0;
758 struct tomoyo_path_info buf;
759 struct tomoyo_request_info r;
760 struct tomoyo_obj_info obj = {
761 .path1 = { .mnt = path->mnt, .dentry = path->dentry },
762 };
763 int idx;
764
765 buf.name = NULL;
766 r.mode = TOMOYO_CONFIG_DISABLED;
767 idx = tomoyo_read_lock();
768 if (acc_mode &&
769 tomoyo_init_request_info(&r, domain, TOMOYO_MAC_FILE_OPEN)
770 != TOMOYO_CONFIG_DISABLED) {
771 if (!tomoyo_get_realpath(&buf, path)) {
772 error = -ENOMEM;
773 goto out;
774 }
775 r.obj = &obj;
776 if (acc_mode & MAY_READ)
777 error = tomoyo_path_permission(&r, TOMOYO_TYPE_READ,
778 &buf);
779 if (!error && (acc_mode & MAY_WRITE))
780 error = tomoyo_path_permission(&r, (flag & O_APPEND) ?
781 TOMOYO_TYPE_APPEND :
782 TOMOYO_TYPE_WRITE,
783 &buf);
784 }
785 out:
786 kfree(buf.name);
787 tomoyo_read_unlock(idx);
788 if (r.mode != TOMOYO_CONFIG_ENFORCING)
789 error = 0;
790 return error;
791 }
792
793 /**
794 * tomoyo_path_perm - Check permission for "unlink", "rmdir", "truncate", "symlink", "append", "chroot" and "unmount".
795 *
796 * @operation: Type of operation.
797 * @path: Pointer to "struct path".
798 * @target: Symlink's target if @operation is TOMOYO_TYPE_SYMLINK,
799 * NULL otherwise.
800 *
801 * Returns 0 on success, negative value otherwise.
802 */
tomoyo_path_perm(const u8 operation,const struct path * path,const char * target)803 int tomoyo_path_perm(const u8 operation, const struct path *path, const char *target)
804 {
805 struct tomoyo_request_info r;
806 struct tomoyo_obj_info obj = {
807 .path1 = { .mnt = path->mnt, .dentry = path->dentry },
808 };
809 int error;
810 struct tomoyo_path_info buf;
811 bool is_enforce;
812 struct tomoyo_path_info symlink_target;
813 int idx;
814
815 if (tomoyo_init_request_info(&r, NULL, tomoyo_p2mac[operation])
816 == TOMOYO_CONFIG_DISABLED)
817 return 0;
818 is_enforce = (r.mode == TOMOYO_CONFIG_ENFORCING);
819 error = -ENOMEM;
820 buf.name = NULL;
821 idx = tomoyo_read_lock();
822 if (!tomoyo_get_realpath(&buf, path))
823 goto out;
824 r.obj = &obj;
825 switch (operation) {
826 case TOMOYO_TYPE_RMDIR:
827 case TOMOYO_TYPE_CHROOT:
828 tomoyo_add_slash(&buf);
829 break;
830 case TOMOYO_TYPE_SYMLINK:
831 symlink_target.name = tomoyo_encode(target);
832 if (!symlink_target.name)
833 goto out;
834 tomoyo_fill_path_info(&symlink_target);
835 obj.symlink_target = &symlink_target;
836 break;
837 }
838 error = tomoyo_path_permission(&r, operation, &buf);
839 if (operation == TOMOYO_TYPE_SYMLINK)
840 kfree(symlink_target.name);
841 out:
842 kfree(buf.name);
843 tomoyo_read_unlock(idx);
844 if (!is_enforce)
845 error = 0;
846 return error;
847 }
848
849 /**
850 * tomoyo_mkdev_perm - Check permission for "mkblock" and "mkchar".
851 *
852 * @operation: Type of operation. (TOMOYO_TYPE_MKCHAR or TOMOYO_TYPE_MKBLOCK)
853 * @path: Pointer to "struct path".
854 * @mode: Create mode.
855 * @dev: Device number.
856 *
857 * Returns 0 on success, negative value otherwise.
858 */
tomoyo_mkdev_perm(const u8 operation,const struct path * path,const unsigned int mode,unsigned int dev)859 int tomoyo_mkdev_perm(const u8 operation, const struct path *path,
860 const unsigned int mode, unsigned int dev)
861 {
862 struct tomoyo_request_info r;
863 struct tomoyo_obj_info obj = {
864 .path1 = { .mnt = path->mnt, .dentry = path->dentry },
865 };
866 int error = -ENOMEM;
867 struct tomoyo_path_info buf;
868 int idx;
869
870 if (tomoyo_init_request_info(&r, NULL, tomoyo_pnnn2mac[operation])
871 == TOMOYO_CONFIG_DISABLED)
872 return 0;
873 idx = tomoyo_read_lock();
874 error = -ENOMEM;
875 if (tomoyo_get_realpath(&buf, path)) {
876 r.obj = &obj;
877 dev = new_decode_dev(dev);
878 r.param_type = TOMOYO_TYPE_MKDEV_ACL;
879 r.param.mkdev.filename = &buf;
880 r.param.mkdev.operation = operation;
881 r.param.mkdev.mode = mode;
882 r.param.mkdev.major = MAJOR(dev);
883 r.param.mkdev.minor = MINOR(dev);
884 tomoyo_check_acl(&r, tomoyo_check_mkdev_acl);
885 error = tomoyo_audit_mkdev_log(&r);
886 kfree(buf.name);
887 }
888 tomoyo_read_unlock(idx);
889 if (r.mode != TOMOYO_CONFIG_ENFORCING)
890 error = 0;
891 return error;
892 }
893
894 /**
895 * tomoyo_path2_perm - Check permission for "rename", "link" and "pivot_root".
896 *
897 * @operation: Type of operation.
898 * @path1: Pointer to "struct path".
899 * @path2: Pointer to "struct path".
900 *
901 * Returns 0 on success, negative value otherwise.
902 */
tomoyo_path2_perm(const u8 operation,const struct path * path1,const struct path * path2)903 int tomoyo_path2_perm(const u8 operation, const struct path *path1,
904 const struct path *path2)
905 {
906 int error = -ENOMEM;
907 struct tomoyo_path_info buf1;
908 struct tomoyo_path_info buf2;
909 struct tomoyo_request_info r;
910 struct tomoyo_obj_info obj = {
911 .path1 = { .mnt = path1->mnt, .dentry = path1->dentry },
912 .path2 = { .mnt = path2->mnt, .dentry = path2->dentry }
913 };
914 int idx;
915
916 if (tomoyo_init_request_info(&r, NULL, tomoyo_pp2mac[operation])
917 == TOMOYO_CONFIG_DISABLED)
918 return 0;
919 buf1.name = NULL;
920 buf2.name = NULL;
921 idx = tomoyo_read_lock();
922 if (!tomoyo_get_realpath(&buf1, path1) ||
923 !tomoyo_get_realpath(&buf2, path2))
924 goto out;
925 switch (operation) {
926 case TOMOYO_TYPE_RENAME:
927 case TOMOYO_TYPE_LINK:
928 if (!d_is_dir(path1->dentry))
929 break;
930 fallthrough;
931 case TOMOYO_TYPE_PIVOT_ROOT:
932 tomoyo_add_slash(&buf1);
933 tomoyo_add_slash(&buf2);
934 break;
935 }
936 r.obj = &obj;
937 r.param_type = TOMOYO_TYPE_PATH2_ACL;
938 r.param.path2.operation = operation;
939 r.param.path2.filename1 = &buf1;
940 r.param.path2.filename2 = &buf2;
941 do {
942 tomoyo_check_acl(&r, tomoyo_check_path2_acl);
943 error = tomoyo_audit_path2_log(&r);
944 } while (error == TOMOYO_RETRY_REQUEST);
945 out:
946 kfree(buf1.name);
947 kfree(buf2.name);
948 tomoyo_read_unlock(idx);
949 if (r.mode != TOMOYO_CONFIG_ENFORCING)
950 error = 0;
951 return error;
952 }
953
954 /**
955 * tomoyo_same_mount_acl - Check for duplicated "struct tomoyo_mount_acl" entry.
956 *
957 * @a: Pointer to "struct tomoyo_acl_info".
958 * @b: Pointer to "struct tomoyo_acl_info".
959 *
960 * Returns true if @a == @b, false otherwise.
961 */
tomoyo_same_mount_acl(const struct tomoyo_acl_info * a,const struct tomoyo_acl_info * b)962 static bool tomoyo_same_mount_acl(const struct tomoyo_acl_info *a,
963 const struct tomoyo_acl_info *b)
964 {
965 const struct tomoyo_mount_acl *p1 = container_of(a, typeof(*p1), head);
966 const struct tomoyo_mount_acl *p2 = container_of(b, typeof(*p2), head);
967
968 return tomoyo_same_name_union(&p1->dev_name, &p2->dev_name) &&
969 tomoyo_same_name_union(&p1->dir_name, &p2->dir_name) &&
970 tomoyo_same_name_union(&p1->fs_type, &p2->fs_type) &&
971 tomoyo_same_number_union(&p1->flags, &p2->flags);
972 }
973
974 /**
975 * tomoyo_update_mount_acl - Write "struct tomoyo_mount_acl" list.
976 *
977 * @param: Pointer to "struct tomoyo_acl_param".
978 *
979 * Returns 0 on success, negative value otherwise.
980 *
981 * Caller holds tomoyo_read_lock().
982 */
tomoyo_update_mount_acl(struct tomoyo_acl_param * param)983 static int tomoyo_update_mount_acl(struct tomoyo_acl_param *param)
984 {
985 struct tomoyo_mount_acl e = { .head.type = TOMOYO_TYPE_MOUNT_ACL };
986 int error;
987
988 if (!tomoyo_parse_name_union(param, &e.dev_name) ||
989 !tomoyo_parse_name_union(param, &e.dir_name) ||
990 !tomoyo_parse_name_union(param, &e.fs_type) ||
991 !tomoyo_parse_number_union(param, &e.flags))
992 error = -EINVAL;
993 else
994 error = tomoyo_update_domain(&e.head, sizeof(e), param,
995 tomoyo_same_mount_acl, NULL);
996 tomoyo_put_name_union(&e.dev_name);
997 tomoyo_put_name_union(&e.dir_name);
998 tomoyo_put_name_union(&e.fs_type);
999 tomoyo_put_number_union(&e.flags);
1000 return error;
1001 }
1002
1003 /**
1004 * tomoyo_write_file - Update file related list.
1005 *
1006 * @param: Pointer to "struct tomoyo_acl_param".
1007 *
1008 * Returns 0 on success, negative value otherwise.
1009 *
1010 * Caller holds tomoyo_read_lock().
1011 */
tomoyo_write_file(struct tomoyo_acl_param * param)1012 int tomoyo_write_file(struct tomoyo_acl_param *param)
1013 {
1014 u16 perm = 0;
1015 u8 type;
1016 const char *operation = tomoyo_read_token(param);
1017
1018 for (type = 0; type < TOMOYO_MAX_PATH_OPERATION; type++)
1019 if (tomoyo_permstr(operation, tomoyo_path_keyword[type]))
1020 perm |= 1 << type;
1021 if (perm)
1022 return tomoyo_update_path_acl(perm, param);
1023 for (type = 0; type < TOMOYO_MAX_PATH2_OPERATION; type++)
1024 if (tomoyo_permstr(operation,
1025 tomoyo_mac_keywords[tomoyo_pp2mac[type]]))
1026 perm |= 1 << type;
1027 if (perm)
1028 return tomoyo_update_path2_acl(perm, param);
1029 for (type = 0; type < TOMOYO_MAX_PATH_NUMBER_OPERATION; type++)
1030 if (tomoyo_permstr(operation,
1031 tomoyo_mac_keywords[tomoyo_pn2mac[type]]))
1032 perm |= 1 << type;
1033 if (perm)
1034 return tomoyo_update_path_number_acl(perm, param);
1035 for (type = 0; type < TOMOYO_MAX_MKDEV_OPERATION; type++)
1036 if (tomoyo_permstr(operation,
1037 tomoyo_mac_keywords[tomoyo_pnnn2mac[type]]))
1038 perm |= 1 << type;
1039 if (perm)
1040 return tomoyo_update_mkdev_acl(perm, param);
1041 if (tomoyo_permstr(operation,
1042 tomoyo_mac_keywords[TOMOYO_MAC_FILE_MOUNT]))
1043 return tomoyo_update_mount_acl(param);
1044 return -EINVAL;
1045 }
1046