Merge tag 'irqchip-fixes-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git...
[platform/kernel/linux-starfive.git] / security / tomoyo / file.c
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  */
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 *
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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 || !path->dentry)
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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 }