xref: /linux/security/tomoyo/condition.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
1 /*
2  * security/tomoyo/condition.c
3  *
4  * Copyright (C) 2005-2011  NTT DATA CORPORATION
5  */
6 
7 #include "common.h"
8 #include <linux/slab.h>
9 
10 /* List of "struct tomoyo_condition". */
11 LIST_HEAD(tomoyo_condition_list);
12 
13 /**
14  * tomoyo_argv - Check argv[] in "struct linux_binbrm".
15  *
16  * @index:   Index number of @arg_ptr.
17  * @arg_ptr: Contents of argv[@index].
18  * @argc:    Length of @argv.
19  * @argv:    Pointer to "struct tomoyo_argv".
20  * @checked: Set to true if @argv[@index] was found.
21  *
22  * Returns true on success, false otherwise.
23  */
24 static bool tomoyo_argv(const unsigned int index, const char *arg_ptr,
25 			const int argc, const struct tomoyo_argv *argv,
26 			u8 *checked)
27 {
28 	int i;
29 	struct tomoyo_path_info arg;
30 	arg.name = arg_ptr;
31 	for (i = 0; i < argc; argv++, checked++, i++) {
32 		bool result;
33 		if (index != argv->index)
34 			continue;
35 		*checked = 1;
36 		tomoyo_fill_path_info(&arg);
37 		result = tomoyo_path_matches_pattern(&arg, argv->value);
38 		if (argv->is_not)
39 			result = !result;
40 		if (!result)
41 			return false;
42 	}
43 	return true;
44 }
45 
46 /**
47  * tomoyo_envp - Check envp[] in "struct linux_binbrm".
48  *
49  * @env_name:  The name of environment variable.
50  * @env_value: The value of environment variable.
51  * @envc:      Length of @envp.
52  * @envp:      Pointer to "struct tomoyo_envp".
53  * @checked:   Set to true if @envp[@env_name] was found.
54  *
55  * Returns true on success, false otherwise.
56  */
57 static bool tomoyo_envp(const char *env_name, const char *env_value,
58 			const int envc, const struct tomoyo_envp *envp,
59 			u8 *checked)
60 {
61 	int i;
62 	struct tomoyo_path_info name;
63 	struct tomoyo_path_info value;
64 	name.name = env_name;
65 	tomoyo_fill_path_info(&name);
66 	value.name = env_value;
67 	tomoyo_fill_path_info(&value);
68 	for (i = 0; i < envc; envp++, checked++, i++) {
69 		bool result;
70 		if (!tomoyo_path_matches_pattern(&name, envp->name))
71 			continue;
72 		*checked = 1;
73 		if (envp->value) {
74 			result = tomoyo_path_matches_pattern(&value,
75 							     envp->value);
76 			if (envp->is_not)
77 				result = !result;
78 		} else {
79 			result = true;
80 			if (!envp->is_not)
81 				result = !result;
82 		}
83 		if (!result)
84 			return false;
85 	}
86 	return true;
87 }
88 
89 /**
90  * tomoyo_scan_bprm - Scan "struct linux_binprm".
91  *
92  * @ee:   Pointer to "struct tomoyo_execve".
93  * @argc: Length of @argc.
94  * @argv: Pointer to "struct tomoyo_argv".
95  * @envc: Length of @envp.
96  * @envp: Poiner to "struct tomoyo_envp".
97  *
98  * Returns true on success, false otherwise.
99  */
100 static bool tomoyo_scan_bprm(struct tomoyo_execve *ee,
101 			     const u16 argc, const struct tomoyo_argv *argv,
102 			     const u16 envc, const struct tomoyo_envp *envp)
103 {
104 	struct linux_binprm *bprm = ee->bprm;
105 	struct tomoyo_page_dump *dump = &ee->dump;
106 	char *arg_ptr = ee->tmp;
107 	int arg_len = 0;
108 	unsigned long pos = bprm->p;
109 	int offset = pos % PAGE_SIZE;
110 	int argv_count = bprm->argc;
111 	int envp_count = bprm->envc;
112 	bool result = true;
113 	u8 local_checked[32];
114 	u8 *checked;
115 	if (argc + envc <= sizeof(local_checked)) {
116 		checked = local_checked;
117 		memset(local_checked, 0, sizeof(local_checked));
118 	} else {
119 		checked = kzalloc(argc + envc, GFP_NOFS);
120 		if (!checked)
121 			return false;
122 	}
123 	while (argv_count || envp_count) {
124 		if (!tomoyo_dump_page(bprm, pos, dump)) {
125 			result = false;
126 			goto out;
127 		}
128 		pos += PAGE_SIZE - offset;
129 		while (offset < PAGE_SIZE) {
130 			/* Read. */
131 			const char *kaddr = dump->data;
132 			const unsigned char c = kaddr[offset++];
133 			if (c && arg_len < TOMOYO_EXEC_TMPSIZE - 10) {
134 				if (c == '\\') {
135 					arg_ptr[arg_len++] = '\\';
136 					arg_ptr[arg_len++] = '\\';
137 				} else if (c > ' ' && c < 127) {
138 					arg_ptr[arg_len++] = c;
139 				} else {
140 					arg_ptr[arg_len++] = '\\';
141 					arg_ptr[arg_len++] = (c >> 6) + '0';
142 					arg_ptr[arg_len++] =
143 						((c >> 3) & 7) + '0';
144 					arg_ptr[arg_len++] = (c & 7) + '0';
145 				}
146 			} else {
147 				arg_ptr[arg_len] = '\0';
148 			}
149 			if (c)
150 				continue;
151 			/* Check. */
152 			if (argv_count) {
153 				if (!tomoyo_argv(bprm->argc - argv_count,
154 						 arg_ptr, argc, argv,
155 						 checked)) {
156 					result = false;
157 					break;
158 				}
159 				argv_count--;
160 			} else if (envp_count) {
161 				char *cp = strchr(arg_ptr, '=');
162 				if (cp) {
163 					*cp = '\0';
164 					if (!tomoyo_envp(arg_ptr, cp + 1,
165 							 envc, envp,
166 							 checked + argc)) {
167 						result = false;
168 						break;
169 					}
170 				}
171 				envp_count--;
172 			} else {
173 				break;
174 			}
175 			arg_len = 0;
176 		}
177 		offset = 0;
178 		if (!result)
179 			break;
180 	}
181 out:
182 	if (result) {
183 		int i;
184 		/* Check not-yet-checked entries. */
185 		for (i = 0; i < argc; i++) {
186 			if (checked[i])
187 				continue;
188 			/*
189 			 * Return true only if all unchecked indexes in
190 			 * bprm->argv[] are not matched.
191 			 */
192 			if (argv[i].is_not)
193 				continue;
194 			result = false;
195 			break;
196 		}
197 		for (i = 0; i < envc; envp++, i++) {
198 			if (checked[argc + i])
199 				continue;
200 			/*
201 			 * Return true only if all unchecked environ variables
202 			 * in bprm->envp[] are either undefined or not matched.
203 			 */
204 			if ((!envp->value && !envp->is_not) ||
205 			    (envp->value && envp->is_not))
206 				continue;
207 			result = false;
208 			break;
209 		}
210 	}
211 	if (checked != local_checked)
212 		kfree(checked);
213 	return result;
214 }
215 
216 /**
217  * tomoyo_scan_exec_realpath - Check "exec.realpath" parameter of "struct tomoyo_condition".
218  *
219  * @file:  Pointer to "struct file".
220  * @ptr:   Pointer to "struct tomoyo_name_union".
221  * @match: True if "exec.realpath=", false if "exec.realpath!=".
222  *
223  * Returns true on success, false otherwise.
224  */
225 static bool tomoyo_scan_exec_realpath(struct file *file,
226 				      const struct tomoyo_name_union *ptr,
227 				      const bool match)
228 {
229 	bool result;
230 	struct tomoyo_path_info exe;
231 	if (!file)
232 		return false;
233 	exe.name = tomoyo_realpath_from_path(&file->f_path);
234 	if (!exe.name)
235 		return false;
236 	tomoyo_fill_path_info(&exe);
237 	result = tomoyo_compare_name_union(&exe, ptr);
238 	kfree(exe.name);
239 	return result == match;
240 }
241 
242 /**
243  * tomoyo_get_dqword - tomoyo_get_name() for a quoted string.
244  *
245  * @start: String to save.
246  *
247  * Returns pointer to "struct tomoyo_path_info" on success, NULL otherwise.
248  */
249 static const struct tomoyo_path_info *tomoyo_get_dqword(char *start)
250 {
251 	char *cp = start + strlen(start) - 1;
252 	if (cp == start || *start++ != '"' || *cp != '"')
253 		return NULL;
254 	*cp = '\0';
255 	if (*start && !tomoyo_correct_word(start))
256 		return NULL;
257 	return tomoyo_get_name(start);
258 }
259 
260 /**
261  * tomoyo_parse_name_union_quoted - Parse a quoted word.
262  *
263  * @param: Pointer to "struct tomoyo_acl_param".
264  * @ptr:   Pointer to "struct tomoyo_name_union".
265  *
266  * Returns true on success, false otherwise.
267  */
268 static bool tomoyo_parse_name_union_quoted(struct tomoyo_acl_param *param,
269 					   struct tomoyo_name_union *ptr)
270 {
271 	char *filename = param->data;
272 	if (*filename == '@')
273 		return tomoyo_parse_name_union(param, ptr);
274 	ptr->filename = tomoyo_get_dqword(filename);
275 	return ptr->filename != NULL;
276 }
277 
278 /**
279  * tomoyo_parse_argv - Parse an argv[] condition part.
280  *
281  * @left:  Lefthand value.
282  * @right: Righthand value.
283  * @argv:  Pointer to "struct tomoyo_argv".
284  *
285  * Returns true on success, false otherwise.
286  */
287 static bool tomoyo_parse_argv(char *left, char *right,
288 			      struct tomoyo_argv *argv)
289 {
290 	if (tomoyo_parse_ulong(&argv->index, &left) !=
291 	    TOMOYO_VALUE_TYPE_DECIMAL || *left++ != ']' || *left)
292 		return false;
293 	argv->value = tomoyo_get_dqword(right);
294 	return argv->value != NULL;
295 }
296 
297 /**
298  * tomoyo_parse_envp - Parse an envp[] condition part.
299  *
300  * @left:  Lefthand value.
301  * @right: Righthand value.
302  * @envp:  Pointer to "struct tomoyo_envp".
303  *
304  * Returns true on success, false otherwise.
305  */
306 static bool tomoyo_parse_envp(char *left, char *right,
307 			      struct tomoyo_envp *envp)
308 {
309 	const struct tomoyo_path_info *name;
310 	const struct tomoyo_path_info *value;
311 	char *cp = left + strlen(left) - 1;
312 	if (*cp-- != ']' || *cp != '"')
313 		goto out;
314 	*cp = '\0';
315 	if (!tomoyo_correct_word(left))
316 		goto out;
317 	name = tomoyo_get_name(left);
318 	if (!name)
319 		goto out;
320 	if (!strcmp(right, "NULL")) {
321 		value = NULL;
322 	} else {
323 		value = tomoyo_get_dqword(right);
324 		if (!value) {
325 			tomoyo_put_name(name);
326 			goto out;
327 		}
328 	}
329 	envp->name = name;
330 	envp->value = value;
331 	return true;
332 out:
333 	return false;
334 }
335 
336 /**
337  * tomoyo_same_condition - Check for duplicated "struct tomoyo_condition" entry.
338  *
339  * @a: Pointer to "struct tomoyo_condition".
340  * @b: Pointer to "struct tomoyo_condition".
341  *
342  * Returns true if @a == @b, false otherwise.
343  */
344 static inline bool tomoyo_same_condition(const struct tomoyo_condition *a,
345 					 const struct tomoyo_condition *b)
346 {
347 	return a->size == b->size && a->condc == b->condc &&
348 		a->numbers_count == b->numbers_count &&
349 		a->names_count == b->names_count &&
350 		a->argc == b->argc && a->envc == b->envc &&
351 		!memcmp(a + 1, b + 1, a->size - sizeof(*a));
352 }
353 
354 /**
355  * tomoyo_condition_type - Get condition type.
356  *
357  * @word: Keyword string.
358  *
359  * Returns one of values in "enum tomoyo_conditions_index" on success,
360  * TOMOYO_MAX_CONDITION_KEYWORD otherwise.
361  */
362 static u8 tomoyo_condition_type(const char *word)
363 {
364 	u8 i;
365 	for (i = 0; i < TOMOYO_MAX_CONDITION_KEYWORD; i++) {
366 		if (!strcmp(word, tomoyo_condition_keyword[i]))
367 			break;
368 	}
369 	return i;
370 }
371 
372 /* Define this to enable debug mode. */
373 /* #define DEBUG_CONDITION */
374 
375 #ifdef DEBUG_CONDITION
376 #define dprintk printk
377 #else
378 #define dprintk(...) do { } while (0)
379 #endif
380 
381 /**
382  * tomoyo_commit_condition - Commit "struct tomoyo_condition".
383  *
384  * @entry: Pointer to "struct tomoyo_condition".
385  *
386  * Returns pointer to "struct tomoyo_condition" on success, NULL otherwise.
387  *
388  * This function merges duplicated entries. This function returns NULL if
389  * @entry is not duplicated but memory quota for policy has exceeded.
390  */
391 static struct tomoyo_condition *tomoyo_commit_condition
392 (struct tomoyo_condition *entry)
393 {
394 	struct tomoyo_condition *ptr;
395 	bool found = false;
396 	if (mutex_lock_interruptible(&tomoyo_policy_lock)) {
397 		dprintk(KERN_WARNING "%u: %s failed\n", __LINE__, __func__);
398 		ptr = NULL;
399 		found = true;
400 		goto out;
401 	}
402 	list_for_each_entry_rcu(ptr, &tomoyo_condition_list, head.list) {
403 		if (!tomoyo_same_condition(ptr, entry))
404 			continue;
405 		/* Same entry found. Share this entry. */
406 		atomic_inc(&ptr->head.users);
407 		found = true;
408 		break;
409 	}
410 	if (!found) {
411 		if (tomoyo_memory_ok(entry)) {
412 			atomic_set(&entry->head.users, 1);
413 			list_add_rcu(&entry->head.list,
414 				     &tomoyo_condition_list);
415 		} else {
416 			found = true;
417 			ptr = NULL;
418 		}
419 	}
420 	mutex_unlock(&tomoyo_policy_lock);
421 out:
422 	if (found) {
423 		tomoyo_del_condition(&entry->head.list);
424 		kfree(entry);
425 		entry = ptr;
426 	}
427 	return entry;
428 }
429 
430 /**
431  * tomoyo_get_condition - Parse condition part.
432  *
433  * @param: Pointer to "struct tomoyo_acl_param".
434  *
435  * Returns pointer to "struct tomoyo_condition" on success, NULL otherwise.
436  */
437 struct tomoyo_condition *tomoyo_get_condition(struct tomoyo_acl_param *param)
438 {
439 	struct tomoyo_condition *entry = NULL;
440 	struct tomoyo_condition_element *condp = NULL;
441 	struct tomoyo_number_union *numbers_p = NULL;
442 	struct tomoyo_name_union *names_p = NULL;
443 	struct tomoyo_argv *argv = NULL;
444 	struct tomoyo_envp *envp = NULL;
445 	struct tomoyo_condition e = { };
446 	char * const start_of_string = param->data;
447 	char * const end_of_string = start_of_string + strlen(start_of_string);
448 	char *pos;
449 rerun:
450 	pos = start_of_string;
451 	while (1) {
452 		u8 left = -1;
453 		u8 right = -1;
454 		char *left_word = pos;
455 		char *cp;
456 		char *right_word;
457 		bool is_not;
458 		if (!*left_word)
459 			break;
460 		/*
461 		 * Since left-hand condition does not allow use of "path_group"
462 		 * or "number_group" and environment variable's names do not
463 		 * accept '=', it is guaranteed that the original line consists
464 		 * of one or more repetition of $left$operator$right blocks
465 		 * where "$left is free from '=' and ' '" and "$operator is
466 		 * either '=' or '!='" and "$right is free from ' '".
467 		 * Therefore, we can reconstruct the original line at the end
468 		 * of dry run even if we overwrite $operator with '\0'.
469 		 */
470 		cp = strchr(pos, ' ');
471 		if (cp) {
472 			*cp = '\0'; /* Will restore later. */
473 			pos = cp + 1;
474 		} else {
475 			pos = "";
476 		}
477 		right_word = strchr(left_word, '=');
478 		if (!right_word || right_word == left_word)
479 			goto out;
480 		is_not = *(right_word - 1) == '!';
481 		if (is_not)
482 			*(right_word++ - 1) = '\0'; /* Will restore later. */
483 		else if (*(right_word + 1) != '=')
484 			*right_word++ = '\0'; /* Will restore later. */
485 		else
486 			goto out;
487 		dprintk(KERN_WARNING "%u: <%s>%s=<%s>\n", __LINE__, left_word,
488 			is_not ? "!" : "", right_word);
489 		if (!strncmp(left_word, "exec.argv[", 10)) {
490 			if (!argv) {
491 				e.argc++;
492 				e.condc++;
493 			} else {
494 				e.argc--;
495 				e.condc--;
496 				left = TOMOYO_ARGV_ENTRY;
497 				argv->is_not = is_not;
498 				if (!tomoyo_parse_argv(left_word + 10,
499 						       right_word, argv++))
500 					goto out;
501 			}
502 			goto store_value;
503 		}
504 		if (!strncmp(left_word, "exec.envp[\"", 11)) {
505 			if (!envp) {
506 				e.envc++;
507 				e.condc++;
508 			} else {
509 				e.envc--;
510 				e.condc--;
511 				left = TOMOYO_ENVP_ENTRY;
512 				envp->is_not = is_not;
513 				if (!tomoyo_parse_envp(left_word + 11,
514 						       right_word, envp++))
515 					goto out;
516 			}
517 			goto store_value;
518 		}
519 		left = tomoyo_condition_type(left_word);
520 		dprintk(KERN_WARNING "%u: <%s> left=%u\n", __LINE__, left_word,
521 			left);
522 		if (left == TOMOYO_MAX_CONDITION_KEYWORD) {
523 			if (!numbers_p) {
524 				e.numbers_count++;
525 			} else {
526 				e.numbers_count--;
527 				left = TOMOYO_NUMBER_UNION;
528 				param->data = left_word;
529 				if (*left_word == '@' ||
530 				    !tomoyo_parse_number_union(param,
531 							       numbers_p++))
532 					goto out;
533 			}
534 		}
535 		if (!condp)
536 			e.condc++;
537 		else
538 			e.condc--;
539 		if (left == TOMOYO_EXEC_REALPATH ||
540 		    left == TOMOYO_SYMLINK_TARGET) {
541 			if (!names_p) {
542 				e.names_count++;
543 			} else {
544 				e.names_count--;
545 				right = TOMOYO_NAME_UNION;
546 				param->data = right_word;
547 				if (!tomoyo_parse_name_union_quoted(param,
548 								    names_p++))
549 					goto out;
550 			}
551 			goto store_value;
552 		}
553 		right = tomoyo_condition_type(right_word);
554 		if (right == TOMOYO_MAX_CONDITION_KEYWORD) {
555 			if (!numbers_p) {
556 				e.numbers_count++;
557 			} else {
558 				e.numbers_count--;
559 				right = TOMOYO_NUMBER_UNION;
560 				param->data = right_word;
561 				if (!tomoyo_parse_number_union(param,
562 							       numbers_p++))
563 					goto out;
564 			}
565 		}
566 store_value:
567 		if (!condp) {
568 			dprintk(KERN_WARNING "%u: dry_run left=%u right=%u "
569 				"match=%u\n", __LINE__, left, right, !is_not);
570 			continue;
571 		}
572 		condp->left = left;
573 		condp->right = right;
574 		condp->equals = !is_not;
575 		dprintk(KERN_WARNING "%u: left=%u right=%u match=%u\n",
576 			__LINE__, condp->left, condp->right,
577 			condp->equals);
578 		condp++;
579 	}
580 	dprintk(KERN_INFO "%u: cond=%u numbers=%u names=%u ac=%u ec=%u\n",
581 		__LINE__, e.condc, e.numbers_count, e.names_count, e.argc,
582 		e.envc);
583 	if (entry) {
584 		BUG_ON(e.names_count | e.numbers_count | e.argc | e.envc |
585 		       e.condc);
586 		return tomoyo_commit_condition(entry);
587 	}
588 	e.size = sizeof(*entry)
589 		+ e.condc * sizeof(struct tomoyo_condition_element)
590 		+ e.numbers_count * sizeof(struct tomoyo_number_union)
591 		+ e.names_count * sizeof(struct tomoyo_name_union)
592 		+ e.argc * sizeof(struct tomoyo_argv)
593 		+ e.envc * sizeof(struct tomoyo_envp);
594 	entry = kzalloc(e.size, GFP_NOFS);
595 	if (!entry)
596 		return NULL;
597 	*entry = e;
598 	condp = (struct tomoyo_condition_element *) (entry + 1);
599 	numbers_p = (struct tomoyo_number_union *) (condp + e.condc);
600 	names_p = (struct tomoyo_name_union *) (numbers_p + e.numbers_count);
601 	argv = (struct tomoyo_argv *) (names_p + e.names_count);
602 	envp = (struct tomoyo_envp *) (argv + e.argc);
603 	{
604 		bool flag = false;
605 		for (pos = start_of_string; pos < end_of_string; pos++) {
606 			if (*pos)
607 				continue;
608 			if (flag) /* Restore " ". */
609 				*pos = ' ';
610 			else if (*(pos + 1) == '=') /* Restore "!=". */
611 				*pos = '!';
612 			else /* Restore "=". */
613 				*pos = '=';
614 			flag = !flag;
615 		}
616 	}
617 	goto rerun;
618 out:
619 	dprintk(KERN_WARNING "%u: %s failed\n", __LINE__, __func__);
620 	if (entry) {
621 		tomoyo_del_condition(&entry->head.list);
622 		kfree(entry);
623 	}
624 	return NULL;
625 }
626 
627 /**
628  * tomoyo_get_attributes - Revalidate "struct inode".
629  *
630  * @obj: Pointer to "struct tomoyo_obj_info".
631  *
632  * Returns nothing.
633  */
634 void tomoyo_get_attributes(struct tomoyo_obj_info *obj)
635 {
636 	u8 i;
637 	struct dentry *dentry = NULL;
638 
639 	for (i = 0; i < TOMOYO_MAX_PATH_STAT; i++) {
640 		struct inode *inode;
641 		switch (i) {
642 		case TOMOYO_PATH1:
643 			dentry = obj->path1.dentry;
644 			if (!dentry)
645 				continue;
646 			break;
647 		case TOMOYO_PATH2:
648 			dentry = obj->path2.dentry;
649 			if (!dentry)
650 				continue;
651 			break;
652 		default:
653 			if (!dentry)
654 				continue;
655 			dentry = dget_parent(dentry);
656 			break;
657 		}
658 		inode = dentry->d_inode;
659 		if (inode) {
660 			struct tomoyo_mini_stat *stat = &obj->stat[i];
661 			stat->uid  = inode->i_uid;
662 			stat->gid  = inode->i_gid;
663 			stat->ino  = inode->i_ino;
664 			stat->mode = inode->i_mode;
665 			stat->dev  = inode->i_sb->s_dev;
666 			stat->rdev = inode->i_rdev;
667 			obj->stat_valid[i] = true;
668 		}
669 		if (i & 1) /* i == TOMOYO_PATH1_PARENT ||
670 			      i == TOMOYO_PATH2_PARENT */
671 			dput(dentry);
672 	}
673 }
674 
675 /**
676  * tomoyo_condition - Check condition part.
677  *
678  * @r:    Pointer to "struct tomoyo_request_info".
679  * @cond: Pointer to "struct tomoyo_condition". Maybe NULL.
680  *
681  * Returns true on success, false otherwise.
682  *
683  * Caller holds tomoyo_read_lock().
684  */
685 bool tomoyo_condition(struct tomoyo_request_info *r,
686 		      const struct tomoyo_condition *cond)
687 {
688 	u32 i;
689 	unsigned long min_v[2] = { 0, 0 };
690 	unsigned long max_v[2] = { 0, 0 };
691 	const struct tomoyo_condition_element *condp;
692 	const struct tomoyo_number_union *numbers_p;
693 	const struct tomoyo_name_union *names_p;
694 	const struct tomoyo_argv *argv;
695 	const struct tomoyo_envp *envp;
696 	struct tomoyo_obj_info *obj;
697 	u16 condc;
698 	u16 argc;
699 	u16 envc;
700 	struct linux_binprm *bprm = NULL;
701 	if (!cond)
702 		return true;
703 	condc = cond->condc;
704 	argc = cond->argc;
705 	envc = cond->envc;
706 	obj = r->obj;
707 	if (r->ee)
708 		bprm = r->ee->bprm;
709 	if (!bprm && (argc || envc))
710 		return false;
711 	condp = (struct tomoyo_condition_element *) (cond + 1);
712 	numbers_p = (const struct tomoyo_number_union *) (condp + condc);
713 	names_p = (const struct tomoyo_name_union *)
714 		(numbers_p + cond->numbers_count);
715 	argv = (const struct tomoyo_argv *) (names_p + cond->names_count);
716 	envp = (const struct tomoyo_envp *) (argv + argc);
717 	for (i = 0; i < condc; i++) {
718 		const bool match = condp->equals;
719 		const u8 left = condp->left;
720 		const u8 right = condp->right;
721 		bool is_bitop[2] = { false, false };
722 		u8 j;
723 		condp++;
724 		/* Check argv[] and envp[] later. */
725 		if (left == TOMOYO_ARGV_ENTRY || left == TOMOYO_ENVP_ENTRY)
726 			continue;
727 		/* Check string expressions. */
728 		if (right == TOMOYO_NAME_UNION) {
729 			const struct tomoyo_name_union *ptr = names_p++;
730 			switch (left) {
731 				struct tomoyo_path_info *symlink;
732 				struct tomoyo_execve *ee;
733 				struct file *file;
734 			case TOMOYO_SYMLINK_TARGET:
735 				symlink = obj ? obj->symlink_target : NULL;
736 				if (!symlink ||
737 				    !tomoyo_compare_name_union(symlink, ptr)
738 				    == match)
739 					goto out;
740 				break;
741 			case TOMOYO_EXEC_REALPATH:
742 				ee = r->ee;
743 				file = ee ? ee->bprm->file : NULL;
744 				if (!tomoyo_scan_exec_realpath(file, ptr,
745 							       match))
746 					goto out;
747 				break;
748 			}
749 			continue;
750 		}
751 		/* Check numeric or bit-op expressions. */
752 		for (j = 0; j < 2; j++) {
753 			const u8 index = j ? right : left;
754 			unsigned long value = 0;
755 			switch (index) {
756 			case TOMOYO_TASK_UID:
757 				value = current_uid();
758 				break;
759 			case TOMOYO_TASK_EUID:
760 				value = current_euid();
761 				break;
762 			case TOMOYO_TASK_SUID:
763 				value = current_suid();
764 				break;
765 			case TOMOYO_TASK_FSUID:
766 				value = current_fsuid();
767 				break;
768 			case TOMOYO_TASK_GID:
769 				value = current_gid();
770 				break;
771 			case TOMOYO_TASK_EGID:
772 				value = current_egid();
773 				break;
774 			case TOMOYO_TASK_SGID:
775 				value = current_sgid();
776 				break;
777 			case TOMOYO_TASK_FSGID:
778 				value = current_fsgid();
779 				break;
780 			case TOMOYO_TASK_PID:
781 				value = tomoyo_sys_getpid();
782 				break;
783 			case TOMOYO_TASK_PPID:
784 				value = tomoyo_sys_getppid();
785 				break;
786 			case TOMOYO_TYPE_IS_SOCKET:
787 				value = S_IFSOCK;
788 				break;
789 			case TOMOYO_TYPE_IS_SYMLINK:
790 				value = S_IFLNK;
791 				break;
792 			case TOMOYO_TYPE_IS_FILE:
793 				value = S_IFREG;
794 				break;
795 			case TOMOYO_TYPE_IS_BLOCK_DEV:
796 				value = S_IFBLK;
797 				break;
798 			case TOMOYO_TYPE_IS_DIRECTORY:
799 				value = S_IFDIR;
800 				break;
801 			case TOMOYO_TYPE_IS_CHAR_DEV:
802 				value = S_IFCHR;
803 				break;
804 			case TOMOYO_TYPE_IS_FIFO:
805 				value = S_IFIFO;
806 				break;
807 			case TOMOYO_MODE_SETUID:
808 				value = S_ISUID;
809 				break;
810 			case TOMOYO_MODE_SETGID:
811 				value = S_ISGID;
812 				break;
813 			case TOMOYO_MODE_STICKY:
814 				value = S_ISVTX;
815 				break;
816 			case TOMOYO_MODE_OWNER_READ:
817 				value = S_IRUSR;
818 				break;
819 			case TOMOYO_MODE_OWNER_WRITE:
820 				value = S_IWUSR;
821 				break;
822 			case TOMOYO_MODE_OWNER_EXECUTE:
823 				value = S_IXUSR;
824 				break;
825 			case TOMOYO_MODE_GROUP_READ:
826 				value = S_IRGRP;
827 				break;
828 			case TOMOYO_MODE_GROUP_WRITE:
829 				value = S_IWGRP;
830 				break;
831 			case TOMOYO_MODE_GROUP_EXECUTE:
832 				value = S_IXGRP;
833 				break;
834 			case TOMOYO_MODE_OTHERS_READ:
835 				value = S_IROTH;
836 				break;
837 			case TOMOYO_MODE_OTHERS_WRITE:
838 				value = S_IWOTH;
839 				break;
840 			case TOMOYO_MODE_OTHERS_EXECUTE:
841 				value = S_IXOTH;
842 				break;
843 			case TOMOYO_EXEC_ARGC:
844 				if (!bprm)
845 					goto out;
846 				value = bprm->argc;
847 				break;
848 			case TOMOYO_EXEC_ENVC:
849 				if (!bprm)
850 					goto out;
851 				value = bprm->envc;
852 				break;
853 			case TOMOYO_NUMBER_UNION:
854 				/* Fetch values later. */
855 				break;
856 			default:
857 				if (!obj)
858 					goto out;
859 				if (!obj->validate_done) {
860 					tomoyo_get_attributes(obj);
861 					obj->validate_done = true;
862 				}
863 				{
864 					u8 stat_index;
865 					struct tomoyo_mini_stat *stat;
866 					switch (index) {
867 					case TOMOYO_PATH1_UID:
868 					case TOMOYO_PATH1_GID:
869 					case TOMOYO_PATH1_INO:
870 					case TOMOYO_PATH1_MAJOR:
871 					case TOMOYO_PATH1_MINOR:
872 					case TOMOYO_PATH1_TYPE:
873 					case TOMOYO_PATH1_DEV_MAJOR:
874 					case TOMOYO_PATH1_DEV_MINOR:
875 					case TOMOYO_PATH1_PERM:
876 						stat_index = TOMOYO_PATH1;
877 						break;
878 					case TOMOYO_PATH2_UID:
879 					case TOMOYO_PATH2_GID:
880 					case TOMOYO_PATH2_INO:
881 					case TOMOYO_PATH2_MAJOR:
882 					case TOMOYO_PATH2_MINOR:
883 					case TOMOYO_PATH2_TYPE:
884 					case TOMOYO_PATH2_DEV_MAJOR:
885 					case TOMOYO_PATH2_DEV_MINOR:
886 					case TOMOYO_PATH2_PERM:
887 						stat_index = TOMOYO_PATH2;
888 						break;
889 					case TOMOYO_PATH1_PARENT_UID:
890 					case TOMOYO_PATH1_PARENT_GID:
891 					case TOMOYO_PATH1_PARENT_INO:
892 					case TOMOYO_PATH1_PARENT_PERM:
893 						stat_index =
894 							TOMOYO_PATH1_PARENT;
895 						break;
896 					case TOMOYO_PATH2_PARENT_UID:
897 					case TOMOYO_PATH2_PARENT_GID:
898 					case TOMOYO_PATH2_PARENT_INO:
899 					case TOMOYO_PATH2_PARENT_PERM:
900 						stat_index =
901 							TOMOYO_PATH2_PARENT;
902 						break;
903 					default:
904 						goto out;
905 					}
906 					if (!obj->stat_valid[stat_index])
907 						goto out;
908 					stat = &obj->stat[stat_index];
909 					switch (index) {
910 					case TOMOYO_PATH1_UID:
911 					case TOMOYO_PATH2_UID:
912 					case TOMOYO_PATH1_PARENT_UID:
913 					case TOMOYO_PATH2_PARENT_UID:
914 						value = stat->uid;
915 						break;
916 					case TOMOYO_PATH1_GID:
917 					case TOMOYO_PATH2_GID:
918 					case TOMOYO_PATH1_PARENT_GID:
919 					case TOMOYO_PATH2_PARENT_GID:
920 						value = stat->gid;
921 						break;
922 					case TOMOYO_PATH1_INO:
923 					case TOMOYO_PATH2_INO:
924 					case TOMOYO_PATH1_PARENT_INO:
925 					case TOMOYO_PATH2_PARENT_INO:
926 						value = stat->ino;
927 						break;
928 					case TOMOYO_PATH1_MAJOR:
929 					case TOMOYO_PATH2_MAJOR:
930 						value = MAJOR(stat->dev);
931 						break;
932 					case TOMOYO_PATH1_MINOR:
933 					case TOMOYO_PATH2_MINOR:
934 						value = MINOR(stat->dev);
935 						break;
936 					case TOMOYO_PATH1_TYPE:
937 					case TOMOYO_PATH2_TYPE:
938 						value = stat->mode & S_IFMT;
939 						break;
940 					case TOMOYO_PATH1_DEV_MAJOR:
941 					case TOMOYO_PATH2_DEV_MAJOR:
942 						value = MAJOR(stat->rdev);
943 						break;
944 					case TOMOYO_PATH1_DEV_MINOR:
945 					case TOMOYO_PATH2_DEV_MINOR:
946 						value = MINOR(stat->rdev);
947 						break;
948 					case TOMOYO_PATH1_PERM:
949 					case TOMOYO_PATH2_PERM:
950 					case TOMOYO_PATH1_PARENT_PERM:
951 					case TOMOYO_PATH2_PARENT_PERM:
952 						value = stat->mode & S_IALLUGO;
953 						break;
954 					}
955 				}
956 				break;
957 			}
958 			max_v[j] = value;
959 			min_v[j] = value;
960 			switch (index) {
961 			case TOMOYO_MODE_SETUID:
962 			case TOMOYO_MODE_SETGID:
963 			case TOMOYO_MODE_STICKY:
964 			case TOMOYO_MODE_OWNER_READ:
965 			case TOMOYO_MODE_OWNER_WRITE:
966 			case TOMOYO_MODE_OWNER_EXECUTE:
967 			case TOMOYO_MODE_GROUP_READ:
968 			case TOMOYO_MODE_GROUP_WRITE:
969 			case TOMOYO_MODE_GROUP_EXECUTE:
970 			case TOMOYO_MODE_OTHERS_READ:
971 			case TOMOYO_MODE_OTHERS_WRITE:
972 			case TOMOYO_MODE_OTHERS_EXECUTE:
973 				is_bitop[j] = true;
974 			}
975 		}
976 		if (left == TOMOYO_NUMBER_UNION) {
977 			/* Fetch values now. */
978 			const struct tomoyo_number_union *ptr = numbers_p++;
979 			min_v[0] = ptr->values[0];
980 			max_v[0] = ptr->values[1];
981 		}
982 		if (right == TOMOYO_NUMBER_UNION) {
983 			/* Fetch values now. */
984 			const struct tomoyo_number_union *ptr = numbers_p++;
985 			if (ptr->group) {
986 				if (tomoyo_number_matches_group(min_v[0],
987 								max_v[0],
988 								ptr->group)
989 				    == match)
990 					continue;
991 			} else {
992 				if ((min_v[0] <= ptr->values[1] &&
993 				     max_v[0] >= ptr->values[0]) == match)
994 					continue;
995 			}
996 			goto out;
997 		}
998 		/*
999 		 * Bit operation is valid only when counterpart value
1000 		 * represents permission.
1001 		 */
1002 		if (is_bitop[0] && is_bitop[1]) {
1003 			goto out;
1004 		} else if (is_bitop[0]) {
1005 			switch (right) {
1006 			case TOMOYO_PATH1_PERM:
1007 			case TOMOYO_PATH1_PARENT_PERM:
1008 			case TOMOYO_PATH2_PERM:
1009 			case TOMOYO_PATH2_PARENT_PERM:
1010 				if (!(max_v[0] & max_v[1]) == !match)
1011 					continue;
1012 			}
1013 			goto out;
1014 		} else if (is_bitop[1]) {
1015 			switch (left) {
1016 			case TOMOYO_PATH1_PERM:
1017 			case TOMOYO_PATH1_PARENT_PERM:
1018 			case TOMOYO_PATH2_PERM:
1019 			case TOMOYO_PATH2_PARENT_PERM:
1020 				if (!(max_v[0] & max_v[1]) == !match)
1021 					continue;
1022 			}
1023 			goto out;
1024 		}
1025 		/* Normal value range comparison. */
1026 		if ((min_v[0] <= max_v[1] && max_v[0] >= min_v[1]) == match)
1027 			continue;
1028 out:
1029 		return false;
1030 	}
1031 	/* Check argv[] and envp[] now. */
1032 	if (r->ee && (argc || envc))
1033 		return tomoyo_scan_bprm(r->ee, argc, argv, envc, envp);
1034 	return true;
1035 }
1036