TOMOYO: Bump version.
[linux-3.10.git] / security / tomoyo / file.c
1 /*
2  * security/tomoyo/file.c
3  *
4  * Copyright (C) 2005-2011  NTT DATA CORPORATION
5  */
6
7 #include "common.h"
8 #include <linux/slab.h>
9
10 /*
11  * Mapping table from "enum tomoyo_path_acl_index" to "enum tomoyo_mac_index".
12  */
13 static const u8 tomoyo_p2mac[TOMOYO_MAX_PATH_OPERATION] = {
14         [TOMOYO_TYPE_EXECUTE]    = TOMOYO_MAC_FILE_EXECUTE,
15         [TOMOYO_TYPE_READ]       = TOMOYO_MAC_FILE_OPEN,
16         [TOMOYO_TYPE_WRITE]      = TOMOYO_MAC_FILE_OPEN,
17         [TOMOYO_TYPE_APPEND]     = TOMOYO_MAC_FILE_OPEN,
18         [TOMOYO_TYPE_UNLINK]     = TOMOYO_MAC_FILE_UNLINK,
19         [TOMOYO_TYPE_GETATTR]    = TOMOYO_MAC_FILE_GETATTR,
20         [TOMOYO_TYPE_RMDIR]      = TOMOYO_MAC_FILE_RMDIR,
21         [TOMOYO_TYPE_TRUNCATE]   = TOMOYO_MAC_FILE_TRUNCATE,
22         [TOMOYO_TYPE_SYMLINK]    = TOMOYO_MAC_FILE_SYMLINK,
23         [TOMOYO_TYPE_CHROOT]     = TOMOYO_MAC_FILE_CHROOT,
24         [TOMOYO_TYPE_UMOUNT]     = TOMOYO_MAC_FILE_UMOUNT,
25 };
26
27 /*
28  * Mapping table from "enum tomoyo_mkdev_acl_index" to "enum tomoyo_mac_index".
29  */
30 const u8 tomoyo_pnnn2mac[TOMOYO_MAX_MKDEV_OPERATION] = {
31         [TOMOYO_TYPE_MKBLOCK] = TOMOYO_MAC_FILE_MKBLOCK,
32         [TOMOYO_TYPE_MKCHAR]  = TOMOYO_MAC_FILE_MKCHAR,
33 };
34
35 /*
36  * Mapping table from "enum tomoyo_path2_acl_index" to "enum tomoyo_mac_index".
37  */
38 const u8 tomoyo_pp2mac[TOMOYO_MAX_PATH2_OPERATION] = {
39         [TOMOYO_TYPE_LINK]       = TOMOYO_MAC_FILE_LINK,
40         [TOMOYO_TYPE_RENAME]     = TOMOYO_MAC_FILE_RENAME,
41         [TOMOYO_TYPE_PIVOT_ROOT] = TOMOYO_MAC_FILE_PIVOT_ROOT,
42 };
43
44 /*
45  * Mapping table from "enum tomoyo_path_number_acl_index" to
46  * "enum tomoyo_mac_index".
47  */
48 const u8 tomoyo_pn2mac[TOMOYO_MAX_PATH_NUMBER_OPERATION] = {
49         [TOMOYO_TYPE_CREATE] = TOMOYO_MAC_FILE_CREATE,
50         [TOMOYO_TYPE_MKDIR]  = TOMOYO_MAC_FILE_MKDIR,
51         [TOMOYO_TYPE_MKFIFO] = TOMOYO_MAC_FILE_MKFIFO,
52         [TOMOYO_TYPE_MKSOCK] = TOMOYO_MAC_FILE_MKSOCK,
53         [TOMOYO_TYPE_IOCTL]  = TOMOYO_MAC_FILE_IOCTL,
54         [TOMOYO_TYPE_CHMOD]  = TOMOYO_MAC_FILE_CHMOD,
55         [TOMOYO_TYPE_CHOWN]  = TOMOYO_MAC_FILE_CHOWN,
56         [TOMOYO_TYPE_CHGRP]  = TOMOYO_MAC_FILE_CHGRP,
57 };
58
59 /**
60  * tomoyo_put_name_union - Drop reference on "struct tomoyo_name_union".
61  *
62  * @ptr: Pointer to "struct tomoyo_name_union".
63  *
64  * Returns nothing.
65  */
66 void tomoyo_put_name_union(struct tomoyo_name_union *ptr)
67 {
68         tomoyo_put_group(ptr->group);
69         tomoyo_put_name(ptr->filename);
70 }
71
72 /**
73  * tomoyo_compare_name_union - Check whether a name matches "struct tomoyo_name_union" or not.
74  *
75  * @name: Pointer to "struct tomoyo_path_info".
76  * @ptr:  Pointer to "struct tomoyo_name_union".
77  *
78  * Returns "struct tomoyo_path_info" if @name matches @ptr, NULL otherwise.
79  */
80 const struct tomoyo_path_info *
81 tomoyo_compare_name_union(const struct tomoyo_path_info *name,
82                           const struct tomoyo_name_union *ptr)
83 {
84         if (ptr->group)
85                 return tomoyo_path_matches_group(name, ptr->group);
86         if (tomoyo_path_matches_pattern(name, ptr->filename))
87                 return ptr->filename;
88         return NULL;
89 }
90
91 /**
92  * tomoyo_put_number_union - Drop reference on "struct tomoyo_number_union".
93  *
94  * @ptr: Pointer to "struct tomoyo_number_union".
95  *
96  * Returns nothing.
97  */
98 void tomoyo_put_number_union(struct tomoyo_number_union *ptr)
99 {
100         tomoyo_put_group(ptr->group);
101 }
102
103 /**
104  * tomoyo_compare_number_union - Check whether a value matches "struct tomoyo_number_union" or not.
105  *
106  * @value: Number to check.
107  * @ptr:   Pointer to "struct tomoyo_number_union".
108  *
109  * Returns true if @value matches @ptr, false otherwise.
110  */
111 bool tomoyo_compare_number_union(const unsigned long value,
112                                  const struct tomoyo_number_union *ptr)
113 {
114         if (ptr->group)
115                 return tomoyo_number_matches_group(value, value, ptr->group);
116         return value >= ptr->values[0] && value <= ptr->values[1];
117 }
118
119 /**
120  * tomoyo_add_slash - Add trailing '/' if needed.
121  *
122  * @buf: Pointer to "struct tomoyo_path_info".
123  *
124  * Returns nothing.
125  *
126  * @buf must be generated by tomoyo_encode() because this function does not
127  * allocate memory for adding '/'.
128  */
129 static void tomoyo_add_slash(struct tomoyo_path_info *buf)
130 {
131         if (buf->is_dir)
132                 return;
133         /*
134          * This is OK because tomoyo_encode() reserves space for appending "/".
135          */
136         strcat((char *) buf->name, "/");
137         tomoyo_fill_path_info(buf);
138 }
139
140 /**
141  * tomoyo_get_realpath - Get realpath.
142  *
143  * @buf:  Pointer to "struct tomoyo_path_info".
144  * @path: Pointer to "struct path".
145  *
146  * Returns true on success, false otherwise.
147  */
148 static bool tomoyo_get_realpath(struct tomoyo_path_info *buf, struct path *path)
149 {
150         buf->name = tomoyo_realpath_from_path(path);
151         if (buf->name) {
152                 tomoyo_fill_path_info(buf);
153                 return true;
154         }
155         return false;
156 }
157
158 /**
159  * tomoyo_audit_path_log - Audit path request log.
160  *
161  * @r: Pointer to "struct tomoyo_request_info".
162  *
163  * Returns 0 on success, negative value otherwise.
164  */
165 static int tomoyo_audit_path_log(struct tomoyo_request_info *r)
166 {
167         return tomoyo_supervisor(r, "file %s %s\n", tomoyo_path_keyword
168                                  [r->param.path.operation],
169                                  r->param.path.filename->name);
170 }
171
172 /**
173  * tomoyo_audit_path2_log - Audit path/path request log.
174  *
175  * @r: Pointer to "struct tomoyo_request_info".
176  *
177  * Returns 0 on success, negative value otherwise.
178  */
179 static int tomoyo_audit_path2_log(struct tomoyo_request_info *r)
180 {
181         return tomoyo_supervisor(r, "file %s %s %s\n", tomoyo_mac_keywords
182                                  [tomoyo_pp2mac[r->param.path2.operation]],
183                                  r->param.path2.filename1->name,
184                                  r->param.path2.filename2->name);
185 }
186
187 /**
188  * tomoyo_audit_mkdev_log - Audit path/number/number/number request log.
189  *
190  * @r: Pointer to "struct tomoyo_request_info".
191  *
192  * Returns 0 on success, negative value otherwise.
193  */
194 static int tomoyo_audit_mkdev_log(struct tomoyo_request_info *r)
195 {
196         return tomoyo_supervisor(r, "file %s %s 0%o %u %u\n",
197                                  tomoyo_mac_keywords
198                                  [tomoyo_pnnn2mac[r->param.mkdev.operation]],
199                                  r->param.mkdev.filename->name,
200                                  r->param.mkdev.mode, r->param.mkdev.major,
201                                  r->param.mkdev.minor);
202 }
203
204 /**
205  * tomoyo_audit_path_number_log - Audit path/number request log.
206  *
207  * @r: Pointer to "struct tomoyo_request_info".
208  *
209  * Returns 0 on success, negative value otherwise.
210  */
211 static int tomoyo_audit_path_number_log(struct tomoyo_request_info *r)
212 {
213         const u8 type = r->param.path_number.operation;
214         u8 radix;
215         char buffer[64];
216         switch (type) {
217         case TOMOYO_TYPE_CREATE:
218         case TOMOYO_TYPE_MKDIR:
219         case TOMOYO_TYPE_MKFIFO:
220         case TOMOYO_TYPE_MKSOCK:
221         case TOMOYO_TYPE_CHMOD:
222                 radix = TOMOYO_VALUE_TYPE_OCTAL;
223                 break;
224         case TOMOYO_TYPE_IOCTL:
225                 radix = TOMOYO_VALUE_TYPE_HEXADECIMAL;
226                 break;
227         default:
228                 radix = TOMOYO_VALUE_TYPE_DECIMAL;
229                 break;
230         }
231         tomoyo_print_ulong(buffer, sizeof(buffer), r->param.path_number.number,
232                            radix);
233         return tomoyo_supervisor(r, "file %s %s %s\n", tomoyo_mac_keywords
234                                  [tomoyo_pn2mac[type]],
235                                  r->param.path_number.filename->name, buffer);
236 }
237
238 /**
239  * tomoyo_check_path_acl - Check permission for path operation.
240  *
241  * @r:   Pointer to "struct tomoyo_request_info".
242  * @ptr: Pointer to "struct tomoyo_acl_info".
243  *
244  * Returns true if granted, false otherwise.
245  *
246  * To be able to use wildcard for domain transition, this function sets
247  * matching entry on success. Since the caller holds tomoyo_read_lock(),
248  * it is safe to set matching entry.
249  */
250 static bool tomoyo_check_path_acl(struct tomoyo_request_info *r,
251                                   const struct tomoyo_acl_info *ptr)
252 {
253         const struct tomoyo_path_acl *acl = container_of(ptr, typeof(*acl),
254                                                          head);
255         if (acl->perm & (1 << r->param.path.operation)) {
256                 r->param.path.matched_path =
257                         tomoyo_compare_name_union(r->param.path.filename,
258                                                   &acl->name);
259                 return r->param.path.matched_path != NULL;
260         }
261         return false;
262 }
263
264 /**
265  * tomoyo_check_path_number_acl - Check permission for path number operation.
266  *
267  * @r:   Pointer to "struct tomoyo_request_info".
268  * @ptr: Pointer to "struct tomoyo_acl_info".
269  *
270  * Returns true if granted, false otherwise.
271  */
272 static bool tomoyo_check_path_number_acl(struct tomoyo_request_info *r,
273                                          const struct tomoyo_acl_info *ptr)
274 {
275         const struct tomoyo_path_number_acl *acl =
276                 container_of(ptr, typeof(*acl), head);
277         return (acl->perm & (1 << r->param.path_number.operation)) &&
278                 tomoyo_compare_number_union(r->param.path_number.number,
279                                             &acl->number) &&
280                 tomoyo_compare_name_union(r->param.path_number.filename,
281                                           &acl->name);
282 }
283
284 /**
285  * tomoyo_check_path2_acl - Check permission for path path operation.
286  *
287  * @r:   Pointer to "struct tomoyo_request_info".
288  * @ptr: Pointer to "struct tomoyo_acl_info".
289  *
290  * Returns true if granted, false otherwise.
291  */
292 static bool tomoyo_check_path2_acl(struct tomoyo_request_info *r,
293                                    const struct tomoyo_acl_info *ptr)
294 {
295         const struct tomoyo_path2_acl *acl =
296                 container_of(ptr, typeof(*acl), head);
297         return (acl->perm & (1 << r->param.path2.operation)) &&
298                 tomoyo_compare_name_union(r->param.path2.filename1, &acl->name1)
299                 && tomoyo_compare_name_union(r->param.path2.filename2,
300                                              &acl->name2);
301 }
302
303 /**
304  * tomoyo_check_mkdev_acl - Check permission for path number number number operation.
305  *
306  * @r:   Pointer to "struct tomoyo_request_info".
307  * @ptr: Pointer to "struct tomoyo_acl_info".
308  *
309  * Returns true if granted, false otherwise.
310  */
311 static bool tomoyo_check_mkdev_acl(struct tomoyo_request_info *r,
312                                    const struct tomoyo_acl_info *ptr)
313 {
314         const struct tomoyo_mkdev_acl *acl =
315                 container_of(ptr, typeof(*acl), head);
316         return (acl->perm & (1 << r->param.mkdev.operation)) &&
317                 tomoyo_compare_number_union(r->param.mkdev.mode,
318                                             &acl->mode) &&
319                 tomoyo_compare_number_union(r->param.mkdev.major,
320                                             &acl->major) &&
321                 tomoyo_compare_number_union(r->param.mkdev.minor,
322                                             &acl->minor) &&
323                 tomoyo_compare_name_union(r->param.mkdev.filename,
324                                           &acl->name);
325 }
326
327 /**
328  * tomoyo_same_path_acl - Check for duplicated "struct tomoyo_path_acl" entry.
329  *
330  * @a: Pointer to "struct tomoyo_acl_info".
331  * @b: Pointer to "struct tomoyo_acl_info".
332  *
333  * Returns true if @a == @b except permission bits, false otherwise.
334  */
335 static bool tomoyo_same_path_acl(const struct tomoyo_acl_info *a,
336                                  const struct tomoyo_acl_info *b)
337 {
338         const struct tomoyo_path_acl *p1 = container_of(a, typeof(*p1), head);
339         const struct tomoyo_path_acl *p2 = container_of(b, typeof(*p2), head);
340         return tomoyo_same_name_union(&p1->name, &p2->name);
341 }
342
343 /**
344  * tomoyo_merge_path_acl - Merge duplicated "struct tomoyo_path_acl" entry.
345  *
346  * @a:         Pointer to "struct tomoyo_acl_info".
347  * @b:         Pointer to "struct tomoyo_acl_info".
348  * @is_delete: True for @a &= ~@b, false for @a |= @b.
349  *
350  * Returns true if @a is empty, false otherwise.
351  */
352 static bool tomoyo_merge_path_acl(struct tomoyo_acl_info *a,
353                                   struct tomoyo_acl_info *b,
354                                   const bool is_delete)
355 {
356         u16 * const a_perm = &container_of(a, struct tomoyo_path_acl, head)
357                 ->perm;
358         u16 perm = *a_perm;
359         const u16 b_perm = container_of(b, struct tomoyo_path_acl, head)->perm;
360         if (is_delete)
361                 perm &= ~b_perm;
362         else
363                 perm |= b_perm;
364         *a_perm = perm;
365         return !perm;
366 }
367
368 /**
369  * tomoyo_update_path_acl - Update "struct tomoyo_path_acl" list.
370  *
371  * @perm:  Permission.
372  * @param: Pointer to "struct tomoyo_acl_param".
373  *
374  * Returns 0 on success, negative value otherwise.
375  *
376  * Caller holds tomoyo_read_lock().
377  */
378 static int tomoyo_update_path_acl(const u16 perm,
379                                   struct tomoyo_acl_param *param)
380 {
381         struct tomoyo_path_acl e = {
382                 .head.type = TOMOYO_TYPE_PATH_ACL,
383                 .perm = perm
384         };
385         int error;
386         if (!tomoyo_parse_name_union(param, &e.name))
387                 error = -EINVAL;
388         else
389                 error = tomoyo_update_domain(&e.head, sizeof(e), param,
390                                              tomoyo_same_path_acl,
391                                              tomoyo_merge_path_acl);
392         tomoyo_put_name_union(&e.name);
393         return error;
394 }
395
396 /**
397  * tomoyo_same_mkdev_acl - Check for duplicated "struct tomoyo_mkdev_acl" entry.
398  *
399  * @a: Pointer to "struct tomoyo_acl_info".
400  * @b: Pointer to "struct tomoyo_acl_info".
401  *
402  * Returns true if @a == @b except permission bits, false otherwise.
403  */
404 static bool tomoyo_same_mkdev_acl(const struct tomoyo_acl_info *a,
405                                          const struct tomoyo_acl_info *b)
406 {
407         const struct tomoyo_mkdev_acl *p1 = container_of(a, typeof(*p1), head);
408         const struct tomoyo_mkdev_acl *p2 = container_of(b, typeof(*p2), head);
409         return tomoyo_same_name_union(&p1->name, &p2->name) &&
410                 tomoyo_same_number_union(&p1->mode, &p2->mode) &&
411                 tomoyo_same_number_union(&p1->major, &p2->major) &&
412                 tomoyo_same_number_union(&p1->minor, &p2->minor);
413 }
414
415 /**
416  * tomoyo_merge_mkdev_acl - Merge duplicated "struct tomoyo_mkdev_acl" entry.
417  *
418  * @a:         Pointer to "struct tomoyo_acl_info".
419  * @b:         Pointer to "struct tomoyo_acl_info".
420  * @is_delete: True for @a &= ~@b, false for @a |= @b.
421  *
422  * Returns true if @a is empty, false otherwise.
423  */
424 static bool tomoyo_merge_mkdev_acl(struct tomoyo_acl_info *a,
425                                    struct tomoyo_acl_info *b,
426                                    const bool is_delete)
427 {
428         u8 *const a_perm = &container_of(a, struct tomoyo_mkdev_acl,
429                                          head)->perm;
430         u8 perm = *a_perm;
431         const u8 b_perm = container_of(b, struct tomoyo_mkdev_acl, head)
432                 ->perm;
433         if (is_delete)
434                 perm &= ~b_perm;
435         else
436                 perm |= b_perm;
437         *a_perm = perm;
438         return !perm;
439 }
440
441 /**
442  * tomoyo_update_mkdev_acl - Update "struct tomoyo_mkdev_acl" list.
443  *
444  * @perm:  Permission.
445  * @param: Pointer to "struct tomoyo_acl_param".
446  *
447  * Returns 0 on success, negative value otherwise.
448  *
449  * Caller holds tomoyo_read_lock().
450  */
451 static int tomoyo_update_mkdev_acl(const u8 perm,
452                                    struct tomoyo_acl_param *param)
453 {
454         struct tomoyo_mkdev_acl e = {
455                 .head.type = TOMOYO_TYPE_MKDEV_ACL,
456                 .perm = perm
457         };
458         int error;
459         if (!tomoyo_parse_name_union(param, &e.name) ||
460             !tomoyo_parse_number_union(param, &e.mode) ||
461             !tomoyo_parse_number_union(param, &e.major) ||
462             !tomoyo_parse_number_union(param, &e.minor))
463                 error = -EINVAL;
464         else
465                 error = tomoyo_update_domain(&e.head, sizeof(e), param,
466                                              tomoyo_same_mkdev_acl,
467                                              tomoyo_merge_mkdev_acl);
468         tomoyo_put_name_union(&e.name);
469         tomoyo_put_number_union(&e.mode);
470         tomoyo_put_number_union(&e.major);
471         tomoyo_put_number_union(&e.minor);
472         return error;
473 }
474
475 /**
476  * tomoyo_same_path2_acl - Check for duplicated "struct tomoyo_path2_acl" entry.
477  *
478  * @a: Pointer to "struct tomoyo_acl_info".
479  * @b: Pointer to "struct tomoyo_acl_info".
480  *
481  * Returns true if @a == @b except permission bits, false otherwise.
482  */
483 static bool tomoyo_same_path2_acl(const struct tomoyo_acl_info *a,
484                                   const struct tomoyo_acl_info *b)
485 {
486         const struct tomoyo_path2_acl *p1 = container_of(a, typeof(*p1), head);
487         const struct tomoyo_path2_acl *p2 = container_of(b, typeof(*p2), head);
488         return tomoyo_same_name_union(&p1->name1, &p2->name1) &&
489                 tomoyo_same_name_union(&p1->name2, &p2->name2);
490 }
491
492 /**
493  * tomoyo_merge_path2_acl - Merge duplicated "struct tomoyo_path2_acl" entry.
494  *
495  * @a:         Pointer to "struct tomoyo_acl_info".
496  * @b:         Pointer to "struct tomoyo_acl_info".
497  * @is_delete: True for @a &= ~@b, false for @a |= @b.
498  *
499  * Returns true if @a is empty, false otherwise.
500  */
501 static bool tomoyo_merge_path2_acl(struct tomoyo_acl_info *a,
502                                    struct tomoyo_acl_info *b,
503                                    const bool is_delete)
504 {
505         u8 * const a_perm = &container_of(a, struct tomoyo_path2_acl, head)
506                 ->perm;
507         u8 perm = *a_perm;
508         const u8 b_perm = container_of(b, struct tomoyo_path2_acl, head)->perm;
509         if (is_delete)
510                 perm &= ~b_perm;
511         else
512                 perm |= b_perm;
513         *a_perm = perm;
514         return !perm;
515 }
516
517 /**
518  * tomoyo_update_path2_acl - Update "struct tomoyo_path2_acl" list.
519  *
520  * @perm:  Permission.
521  * @param: Pointer to "struct tomoyo_acl_param".
522  *
523  * Returns 0 on success, negative value otherwise.
524  *
525  * Caller holds tomoyo_read_lock().
526  */
527 static int tomoyo_update_path2_acl(const u8 perm,
528                                    struct tomoyo_acl_param *param)
529 {
530         struct tomoyo_path2_acl e = {
531                 .head.type = TOMOYO_TYPE_PATH2_ACL,
532                 .perm = perm
533         };
534         int error;
535         if (!tomoyo_parse_name_union(param, &e.name1) ||
536             !tomoyo_parse_name_union(param, &e.name2))
537                 error = -EINVAL;
538         else
539                 error = tomoyo_update_domain(&e.head, sizeof(e), param,
540                                              tomoyo_same_path2_acl,
541                                              tomoyo_merge_path2_acl);
542         tomoyo_put_name_union(&e.name1);
543         tomoyo_put_name_union(&e.name2);
544         return error;
545 }
546
547 /**
548  * tomoyo_path_permission - Check permission for single path operation.
549  *
550  * @r:         Pointer to "struct tomoyo_request_info".
551  * @operation: Type of operation.
552  * @filename:  Filename to check.
553  *
554  * Returns 0 on success, negative value otherwise.
555  *
556  * Caller holds tomoyo_read_lock().
557  */
558 int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
559                            const struct tomoyo_path_info *filename)
560 {
561         int error;
562
563         r->type = tomoyo_p2mac[operation];
564         r->mode = tomoyo_get_mode(r->domain->ns, r->profile, r->type);
565         if (r->mode == TOMOYO_CONFIG_DISABLED)
566                 return 0;
567         r->param_type = TOMOYO_TYPE_PATH_ACL;
568         r->param.path.filename = filename;
569         r->param.path.operation = operation;
570         do {
571                 tomoyo_check_acl(r, tomoyo_check_path_acl);
572                 error = tomoyo_audit_path_log(r);
573                 /*
574                  * Do not retry for execute request, for alias may have
575                  * changed.
576                  */
577         } while (error == TOMOYO_RETRY_REQUEST &&
578                  operation != TOMOYO_TYPE_EXECUTE);
579         return error;
580 }
581
582 /**
583  * tomoyo_same_path_number_acl - Check for duplicated "struct tomoyo_path_number_acl" entry.
584  *
585  * @a: Pointer to "struct tomoyo_acl_info".
586  * @b: Pointer to "struct tomoyo_acl_info".
587  *
588  * Returns true if @a == @b except permission bits, false otherwise.
589  */
590 static bool tomoyo_same_path_number_acl(const struct tomoyo_acl_info *a,
591                                         const struct tomoyo_acl_info *b)
592 {
593         const struct tomoyo_path_number_acl *p1 = container_of(a, typeof(*p1),
594                                                                head);
595         const struct tomoyo_path_number_acl *p2 = container_of(b, typeof(*p2),
596                                                                head);
597         return tomoyo_same_name_union(&p1->name, &p2->name) &&
598                 tomoyo_same_number_union(&p1->number, &p2->number);
599 }
600
601 /**
602  * tomoyo_merge_path_number_acl - Merge duplicated "struct tomoyo_path_number_acl" entry.
603  *
604  * @a:         Pointer to "struct tomoyo_acl_info".
605  * @b:         Pointer to "struct tomoyo_acl_info".
606  * @is_delete: True for @a &= ~@b, false for @a |= @b.
607  *
608  * Returns true if @a is empty, false otherwise.
609  */
610 static bool tomoyo_merge_path_number_acl(struct tomoyo_acl_info *a,
611                                          struct tomoyo_acl_info *b,
612                                          const bool is_delete)
613 {
614         u8 * const a_perm = &container_of(a, struct tomoyo_path_number_acl,
615                                           head)->perm;
616         u8 perm = *a_perm;
617         const u8 b_perm = container_of(b, struct tomoyo_path_number_acl, head)
618                 ->perm;
619         if (is_delete)
620                 perm &= ~b_perm;
621         else
622                 perm |= b_perm;
623         *a_perm = perm;
624         return !perm;
625 }
626
627 /**
628  * tomoyo_update_path_number_acl - Update ioctl/chmod/chown/chgrp ACL.
629  *
630  * @perm:  Permission.
631  * @param: Pointer to "struct tomoyo_acl_param".
632  *
633  * Returns 0 on success, negative value otherwise.
634  */
635 static int tomoyo_update_path_number_acl(const u8 perm,
636                                          struct tomoyo_acl_param *param)
637 {
638         struct tomoyo_path_number_acl e = {
639                 .head.type = TOMOYO_TYPE_PATH_NUMBER_ACL,
640                 .perm = perm
641         };
642         int error;
643         if (!tomoyo_parse_name_union(param, &e.name) ||
644             !tomoyo_parse_number_union(param, &e.number))
645                 error = -EINVAL;
646         else
647                 error = tomoyo_update_domain(&e.head, sizeof(e), param,
648                                              tomoyo_same_path_number_acl,
649                                              tomoyo_merge_path_number_acl);
650         tomoyo_put_name_union(&e.name);
651         tomoyo_put_number_union(&e.number);
652         return error;
653 }
654
655 /**
656  * tomoyo_path_number_perm - Check permission for "create", "mkdir", "mkfifo", "mksock", "ioctl", "chmod", "chown", "chgrp".
657  *
658  * @type:   Type of operation.
659  * @path:   Pointer to "struct path".
660  * @number: Number.
661  *
662  * Returns 0 on success, negative value otherwise.
663  */
664 int tomoyo_path_number_perm(const u8 type, struct path *path,
665                             unsigned long number)
666 {
667         struct tomoyo_request_info r;
668         struct tomoyo_obj_info obj = {
669                 .path1 = *path,
670         };
671         int error = -ENOMEM;
672         struct tomoyo_path_info buf;
673         int idx;
674
675         if (tomoyo_init_request_info(&r, NULL, tomoyo_pn2mac[type])
676             == TOMOYO_CONFIG_DISABLED || !path->dentry)
677                 return 0;
678         idx = tomoyo_read_lock();
679         if (!tomoyo_get_realpath(&buf, path))
680                 goto out;
681         r.obj = &obj;
682         if (type == TOMOYO_TYPE_MKDIR)
683                 tomoyo_add_slash(&buf);
684         r.param_type = TOMOYO_TYPE_PATH_NUMBER_ACL;
685         r.param.path_number.operation = type;
686         r.param.path_number.filename = &buf;
687         r.param.path_number.number = number;
688         do {
689                 tomoyo_check_acl(&r, tomoyo_check_path_number_acl);
690                 error = tomoyo_audit_path_number_log(&r);
691         } while (error == TOMOYO_RETRY_REQUEST);
692         kfree(buf.name);
693  out:
694         tomoyo_read_unlock(idx);
695         if (r.mode != TOMOYO_CONFIG_ENFORCING)
696                 error = 0;
697         return error;
698 }
699
700 /**
701  * tomoyo_check_open_permission - Check permission for "read" and "write".
702  *
703  * @domain: Pointer to "struct tomoyo_domain_info".
704  * @path:   Pointer to "struct path".
705  * @flag:   Flags for open().
706  *
707  * Returns 0 on success, negative value otherwise.
708  */
709 int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
710                                  struct path *path, const int flag)
711 {
712         const u8 acc_mode = ACC_MODE(flag);
713         int error = 0;
714         struct tomoyo_path_info buf;
715         struct tomoyo_request_info r;
716         struct tomoyo_obj_info obj = {
717                 .path1 = *path,
718         };
719         int idx;
720
721         buf.name = NULL;
722         r.mode = TOMOYO_CONFIG_DISABLED;
723         idx = tomoyo_read_lock();
724         if (acc_mode &&
725             tomoyo_init_request_info(&r, domain, TOMOYO_MAC_FILE_OPEN)
726             != TOMOYO_CONFIG_DISABLED) {
727                 if (!tomoyo_get_realpath(&buf, path)) {
728                         error = -ENOMEM;
729                         goto out;
730                 }
731                 r.obj = &obj;
732                 if (acc_mode & MAY_READ)
733                         error = tomoyo_path_permission(&r, TOMOYO_TYPE_READ,
734                                                        &buf);
735                 if (!error && (acc_mode & MAY_WRITE))
736                         error = tomoyo_path_permission(&r, (flag & O_APPEND) ?
737                                                        TOMOYO_TYPE_APPEND :
738                                                        TOMOYO_TYPE_WRITE,
739                                                        &buf);
740         }
741  out:
742         kfree(buf.name);
743         tomoyo_read_unlock(idx);
744         if (r.mode != TOMOYO_CONFIG_ENFORCING)
745                 error = 0;
746         return error;
747 }
748
749 /**
750  * tomoyo_path_perm - Check permission for "unlink", "rmdir", "truncate", "symlink", "append", "chroot" and "unmount".
751  *
752  * @operation: Type of operation.
753  * @path:      Pointer to "struct path".
754  * @target:    Symlink's target if @operation is TOMOYO_TYPE_SYMLINK,
755  *             NULL otherwise.
756  *
757  * Returns 0 on success, negative value otherwise.
758  */
759 int tomoyo_path_perm(const u8 operation, struct path *path, const char *target)
760 {
761         struct tomoyo_request_info r;
762         struct tomoyo_obj_info obj = {
763                 .path1 = *path,
764         };
765         int error;
766         struct tomoyo_path_info buf;
767         bool is_enforce;
768         struct tomoyo_path_info symlink_target;
769         int idx;
770
771         if (tomoyo_init_request_info(&r, NULL, tomoyo_p2mac[operation])
772             == TOMOYO_CONFIG_DISABLED)
773                 return 0;
774         is_enforce = (r.mode == TOMOYO_CONFIG_ENFORCING);
775         error = -ENOMEM;
776         buf.name = NULL;
777         idx = tomoyo_read_lock();
778         if (!tomoyo_get_realpath(&buf, path))
779                 goto out;
780         r.obj = &obj;
781         switch (operation) {
782         case TOMOYO_TYPE_RMDIR:
783         case TOMOYO_TYPE_CHROOT:
784                 tomoyo_add_slash(&buf);
785                 break;
786         case TOMOYO_TYPE_SYMLINK:
787                 symlink_target.name = tomoyo_encode(target);
788                 if (!symlink_target.name)
789                         goto out;
790                 tomoyo_fill_path_info(&symlink_target);
791                 obj.symlink_target = &symlink_target;
792                 break;
793         }
794         error = tomoyo_path_permission(&r, operation, &buf);
795         if (operation == TOMOYO_TYPE_SYMLINK)
796                 kfree(symlink_target.name);
797  out:
798         kfree(buf.name);
799         tomoyo_read_unlock(idx);
800         if (!is_enforce)
801                 error = 0;
802         return error;
803 }
804
805 /**
806  * tomoyo_mkdev_perm - Check permission for "mkblock" and "mkchar".
807  *
808  * @operation: Type of operation. (TOMOYO_TYPE_MKCHAR or TOMOYO_TYPE_MKBLOCK)
809  * @path:      Pointer to "struct path".
810  * @mode:      Create mode.
811  * @dev:       Device number.
812  *
813  * Returns 0 on success, negative value otherwise.
814  */
815 int tomoyo_mkdev_perm(const u8 operation, struct path *path,
816                       const unsigned int mode, unsigned int dev)
817 {
818         struct tomoyo_request_info r;
819         struct tomoyo_obj_info obj = {
820                 .path1 = *path,
821         };
822         int error = -ENOMEM;
823         struct tomoyo_path_info buf;
824         int idx;
825
826         if (tomoyo_init_request_info(&r, NULL, tomoyo_pnnn2mac[operation])
827             == TOMOYO_CONFIG_DISABLED)
828                 return 0;
829         idx = tomoyo_read_lock();
830         error = -ENOMEM;
831         if (tomoyo_get_realpath(&buf, path)) {
832                 r.obj = &obj;
833                 dev = new_decode_dev(dev);
834                 r.param_type = TOMOYO_TYPE_MKDEV_ACL;
835                 r.param.mkdev.filename = &buf;
836                 r.param.mkdev.operation = operation;
837                 r.param.mkdev.mode = mode;
838                 r.param.mkdev.major = MAJOR(dev);
839                 r.param.mkdev.minor = MINOR(dev);
840                 tomoyo_check_acl(&r, tomoyo_check_mkdev_acl);
841                 error = tomoyo_audit_mkdev_log(&r);
842                 kfree(buf.name);
843         }
844         tomoyo_read_unlock(idx);
845         if (r.mode != TOMOYO_CONFIG_ENFORCING)
846                 error = 0;
847         return error;
848 }
849
850 /**
851  * tomoyo_path2_perm - Check permission for "rename", "link" and "pivot_root".
852  *
853  * @operation: Type of operation.
854  * @path1:      Pointer to "struct path".
855  * @path2:      Pointer to "struct path".
856  *
857  * Returns 0 on success, negative value otherwise.
858  */
859 int tomoyo_path2_perm(const u8 operation, struct path *path1,
860                       struct path *path2)
861 {
862         int error = -ENOMEM;
863         struct tomoyo_path_info buf1;
864         struct tomoyo_path_info buf2;
865         struct tomoyo_request_info r;
866         struct tomoyo_obj_info obj = {
867                 .path1 = *path1,
868                 .path2 = *path2,
869         };
870         int idx;
871
872         if (tomoyo_init_request_info(&r, NULL, tomoyo_pp2mac[operation])
873             == TOMOYO_CONFIG_DISABLED)
874                 return 0;
875         buf1.name = NULL;
876         buf2.name = NULL;
877         idx = tomoyo_read_lock();
878         if (!tomoyo_get_realpath(&buf1, path1) ||
879             !tomoyo_get_realpath(&buf2, path2))
880                 goto out;
881         switch (operation) {
882                 struct dentry *dentry;
883         case TOMOYO_TYPE_RENAME:
884         case TOMOYO_TYPE_LINK:
885                 dentry = path1->dentry;
886                 if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
887                         break;
888                 /* fall through */
889         case TOMOYO_TYPE_PIVOT_ROOT:
890                 tomoyo_add_slash(&buf1);
891                 tomoyo_add_slash(&buf2);
892                 break;
893         }
894         r.obj = &obj;
895         r.param_type = TOMOYO_TYPE_PATH2_ACL;
896         r.param.path2.operation = operation;
897         r.param.path2.filename1 = &buf1;
898         r.param.path2.filename2 = &buf2;
899         do {
900                 tomoyo_check_acl(&r, tomoyo_check_path2_acl);
901                 error = tomoyo_audit_path2_log(&r);
902         } while (error == TOMOYO_RETRY_REQUEST);
903  out:
904         kfree(buf1.name);
905         kfree(buf2.name);
906         tomoyo_read_unlock(idx);
907         if (r.mode != TOMOYO_CONFIG_ENFORCING)
908                 error = 0;
909         return error;
910 }
911
912 /**
913  * tomoyo_same_mount_acl - Check for duplicated "struct tomoyo_mount_acl" entry.
914  *
915  * @a: Pointer to "struct tomoyo_acl_info".
916  * @b: Pointer to "struct tomoyo_acl_info".
917  *
918  * Returns true if @a == @b, false otherwise.
919  */
920 static bool tomoyo_same_mount_acl(const struct tomoyo_acl_info *a,
921                                   const struct tomoyo_acl_info *b)
922 {
923         const struct tomoyo_mount_acl *p1 = container_of(a, typeof(*p1), head);
924         const struct tomoyo_mount_acl *p2 = container_of(b, typeof(*p2), head);
925         return tomoyo_same_name_union(&p1->dev_name, &p2->dev_name) &&
926                 tomoyo_same_name_union(&p1->dir_name, &p2->dir_name) &&
927                 tomoyo_same_name_union(&p1->fs_type, &p2->fs_type) &&
928                 tomoyo_same_number_union(&p1->flags, &p2->flags);
929 }
930
931 /**
932  * tomoyo_update_mount_acl - Write "struct tomoyo_mount_acl" list.
933  *
934  * @param: Pointer to "struct tomoyo_acl_param".
935  *
936  * Returns 0 on success, negative value otherwise.
937  *
938  * Caller holds tomoyo_read_lock().
939  */
940 static int tomoyo_update_mount_acl(struct tomoyo_acl_param *param)
941 {
942         struct tomoyo_mount_acl e = { .head.type = TOMOYO_TYPE_MOUNT_ACL };
943         int error;
944         if (!tomoyo_parse_name_union(param, &e.dev_name) ||
945             !tomoyo_parse_name_union(param, &e.dir_name) ||
946             !tomoyo_parse_name_union(param, &e.fs_type) ||
947             !tomoyo_parse_number_union(param, &e.flags))
948                 error = -EINVAL;
949         else
950                 error = tomoyo_update_domain(&e.head, sizeof(e), param,
951                                              tomoyo_same_mount_acl, NULL);
952         tomoyo_put_name_union(&e.dev_name);
953         tomoyo_put_name_union(&e.dir_name);
954         tomoyo_put_name_union(&e.fs_type);
955         tomoyo_put_number_union(&e.flags);
956         return error;
957 }
958
959 /**
960  * tomoyo_write_file - Update file related list.
961  *
962  * @param: Pointer to "struct tomoyo_acl_param".
963  *
964  * Returns 0 on success, negative value otherwise.
965  *
966  * Caller holds tomoyo_read_lock().
967  */
968 int tomoyo_write_file(struct tomoyo_acl_param *param)
969 {
970         u16 perm = 0;
971         u8 type;
972         const char *operation = tomoyo_read_token(param);
973         for (type = 0; type < TOMOYO_MAX_PATH_OPERATION; type++)
974                 if (tomoyo_permstr(operation, tomoyo_path_keyword[type]))
975                         perm |= 1 << type;
976         if (perm)
977                 return tomoyo_update_path_acl(perm, param);
978         for (type = 0; type < TOMOYO_MAX_PATH2_OPERATION; type++)
979                 if (tomoyo_permstr(operation,
980                                    tomoyo_mac_keywords[tomoyo_pp2mac[type]]))
981                         perm |= 1 << type;
982         if (perm)
983                 return tomoyo_update_path2_acl(perm, param);
984         for (type = 0; type < TOMOYO_MAX_PATH_NUMBER_OPERATION; type++)
985                 if (tomoyo_permstr(operation,
986                                    tomoyo_mac_keywords[tomoyo_pn2mac[type]]))
987                         perm |= 1 << type;
988         if (perm)
989                 return tomoyo_update_path_number_acl(perm, param);
990         for (type = 0; type < TOMOYO_MAX_MKDEV_OPERATION; type++)
991                 if (tomoyo_permstr(operation,
992                                    tomoyo_mac_keywords[tomoyo_pnnn2mac[type]]))
993                         perm |= 1 << type;
994         if (perm)
995                 return tomoyo_update_mkdev_acl(perm, param);
996         if (tomoyo_permstr(operation,
997                            tomoyo_mac_keywords[TOMOYO_MAC_FILE_MOUNT]))
998                 return tomoyo_update_mount_acl(param);
999         return -EINVAL;
1000 }