1 /*
2 * security/tomoyo/util.c
3 *
4 * Utility functions for TOMOYO.
5 *
6 * Copyright (C) 2005-2010 NTT DATA CORPORATION
7 */
8
9 #include <linux/slab.h>
10 #include "common.h"
11
12 /* Lock for protecting policy. */
13 DEFINE_MUTEX(tomoyo_policy_lock);
14
15 /* Has /sbin/init started? */
16 bool tomoyo_policy_loaded;
17
18 /**
19 * tomoyo_parse_ulong - Parse an "unsigned long" value.
20 *
21 * @result: Pointer to "unsigned long".
22 * @str: Pointer to string to parse.
23 *
24 * Returns value type on success, 0 otherwise.
25 *
26 * The @src is updated to point the first character after the value
27 * on success.
28 */
tomoyo_parse_ulong(unsigned long * result,char ** str)29 static u8 tomoyo_parse_ulong(unsigned long *result, char **str)
30 {
31 const char *cp = *str;
32 char *ep;
33 int base = 10;
34 if (*cp == '0') {
35 char c = *(cp + 1);
36 if (c == 'x' || c == 'X') {
37 base = 16;
38 cp += 2;
39 } else if (c >= '0' && c <= '7') {
40 base = 8;
41 cp++;
42 }
43 }
44 *result = simple_strtoul(cp, &ep, base);
45 if (cp == ep)
46 return 0;
47 *str = ep;
48 switch (base) {
49 case 16:
50 return TOMOYO_VALUE_TYPE_HEXADECIMAL;
51 case 8:
52 return TOMOYO_VALUE_TYPE_OCTAL;
53 default:
54 return TOMOYO_VALUE_TYPE_DECIMAL;
55 }
56 }
57
58 /**
59 * tomoyo_print_ulong - Print an "unsigned long" value.
60 *
61 * @buffer: Pointer to buffer.
62 * @buffer_len: Size of @buffer.
63 * @value: An "unsigned long" value.
64 * @type: Type of @value.
65 *
66 * Returns nothing.
67 */
tomoyo_print_ulong(char * buffer,const int buffer_len,const unsigned long value,const u8 type)68 void tomoyo_print_ulong(char *buffer, const int buffer_len,
69 const unsigned long value, const u8 type)
70 {
71 if (type == TOMOYO_VALUE_TYPE_DECIMAL)
72 snprintf(buffer, buffer_len, "%lu", value);
73 else if (type == TOMOYO_VALUE_TYPE_OCTAL)
74 snprintf(buffer, buffer_len, "0%lo", value);
75 else if (type == TOMOYO_VALUE_TYPE_HEXADECIMAL)
76 snprintf(buffer, buffer_len, "0x%lX", value);
77 else
78 snprintf(buffer, buffer_len, "type(%u)", type);
79 }
80
81 /**
82 * tomoyo_parse_name_union - Parse a tomoyo_name_union.
83 *
84 * @filename: Name or name group.
85 * @ptr: Pointer to "struct tomoyo_name_union".
86 *
87 * Returns true on success, false otherwise.
88 */
tomoyo_parse_name_union(const char * filename,struct tomoyo_name_union * ptr)89 bool tomoyo_parse_name_union(const char *filename,
90 struct tomoyo_name_union *ptr)
91 {
92 if (!tomoyo_correct_word(filename))
93 return false;
94 if (filename[0] == '@') {
95 ptr->group = tomoyo_get_group(filename + 1, TOMOYO_PATH_GROUP);
96 ptr->is_group = true;
97 return ptr->group != NULL;
98 }
99 ptr->filename = tomoyo_get_name(filename);
100 ptr->is_group = false;
101 return ptr->filename != NULL;
102 }
103
104 /**
105 * tomoyo_parse_number_union - Parse a tomoyo_number_union.
106 *
107 * @data: Number or number range or number group.
108 * @ptr: Pointer to "struct tomoyo_number_union".
109 *
110 * Returns true on success, false otherwise.
111 */
tomoyo_parse_number_union(char * data,struct tomoyo_number_union * num)112 bool tomoyo_parse_number_union(char *data, struct tomoyo_number_union *num)
113 {
114 u8 type;
115 unsigned long v;
116 memset(num, 0, sizeof(*num));
117 if (data[0] == '@') {
118 if (!tomoyo_correct_word(data))
119 return false;
120 num->group = tomoyo_get_group(data + 1, TOMOYO_NUMBER_GROUP);
121 num->is_group = true;
122 return num->group != NULL;
123 }
124 type = tomoyo_parse_ulong(&v, &data);
125 if (!type)
126 return false;
127 num->values[0] = v;
128 num->min_type = type;
129 if (!*data) {
130 num->values[1] = v;
131 num->max_type = type;
132 return true;
133 }
134 if (*data++ != '-')
135 return false;
136 type = tomoyo_parse_ulong(&v, &data);
137 if (!type || *data)
138 return false;
139 num->values[1] = v;
140 num->max_type = type;
141 return true;
142 }
143
144 /**
145 * tomoyo_byte_range - Check whether the string is a \ooo style octal value.
146 *
147 * @str: Pointer to the string.
148 *
149 * Returns true if @str is a \ooo style octal value, false otherwise.
150 *
151 * TOMOYO uses \ooo style representation for 0x01 - 0x20 and 0x7F - 0xFF.
152 * This function verifies that \ooo is in valid range.
153 */
tomoyo_byte_range(const char * str)154 static inline bool tomoyo_byte_range(const char *str)
155 {
156 return *str >= '0' && *str++ <= '3' &&
157 *str >= '0' && *str++ <= '7' &&
158 *str >= '0' && *str <= '7';
159 }
160
161 /**
162 * tomoyo_alphabet_char - Check whether the character is an alphabet.
163 *
164 * @c: The character to check.
165 *
166 * Returns true if @c is an alphabet character, false otherwise.
167 */
tomoyo_alphabet_char(const char c)168 static inline bool tomoyo_alphabet_char(const char c)
169 {
170 return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
171 }
172
173 /**
174 * tomoyo_make_byte - Make byte value from three octal characters.
175 *
176 * @c1: The first character.
177 * @c2: The second character.
178 * @c3: The third character.
179 *
180 * Returns byte value.
181 */
tomoyo_make_byte(const u8 c1,const u8 c2,const u8 c3)182 static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
183 {
184 return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
185 }
186
187 /**
188 * tomoyo_str_starts - Check whether the given string starts with the given keyword.
189 *
190 * @src: Pointer to pointer to the string.
191 * @find: Pointer to the keyword.
192 *
193 * Returns true if @src starts with @find, false otherwise.
194 *
195 * The @src is updated to point the first character after the @find
196 * if @src starts with @find.
197 */
tomoyo_str_starts(char ** src,const char * find)198 bool tomoyo_str_starts(char **src, const char *find)
199 {
200 const int len = strlen(find);
201 char *tmp = *src;
202
203 if (strncmp(tmp, find, len))
204 return false;
205 tmp += len;
206 *src = tmp;
207 return true;
208 }
209
210 /**
211 * tomoyo_normalize_line - Format string.
212 *
213 * @buffer: The line to normalize.
214 *
215 * Leading and trailing whitespaces are removed.
216 * Multiple whitespaces are packed into single space.
217 *
218 * Returns nothing.
219 */
tomoyo_normalize_line(unsigned char * buffer)220 void tomoyo_normalize_line(unsigned char *buffer)
221 {
222 unsigned char *sp = buffer;
223 unsigned char *dp = buffer;
224 bool first = true;
225
226 while (tomoyo_invalid(*sp))
227 sp++;
228 while (*sp) {
229 if (!first)
230 *dp++ = ' ';
231 first = false;
232 while (tomoyo_valid(*sp))
233 *dp++ = *sp++;
234 while (tomoyo_invalid(*sp))
235 sp++;
236 }
237 *dp = '\0';
238 }
239
240 /**
241 * tomoyo_tokenize - Tokenize string.
242 *
243 * @buffer: The line to tokenize.
244 * @w: Pointer to "char *".
245 * @size: Sizeof @w .
246 *
247 * Returns true on success, false otherwise.
248 */
tomoyo_tokenize(char * buffer,char * w[],size_t size)249 bool tomoyo_tokenize(char *buffer, char *w[], size_t size)
250 {
251 int count = size / sizeof(char *);
252 int i;
253 for (i = 0; i < count; i++)
254 w[i] = "";
255 for (i = 0; i < count; i++) {
256 char *cp = strchr(buffer, ' ');
257 if (cp)
258 *cp = '\0';
259 w[i] = buffer;
260 if (!cp)
261 break;
262 buffer = cp + 1;
263 }
264 return i < count || !*buffer;
265 }
266
267 /**
268 * tomoyo_correct_word2 - Validate a string.
269 *
270 * @string: The string to check. May be non-'\0'-terminated.
271 * @len: Length of @string.
272 *
273 * Check whether the given string follows the naming rules.
274 * Returns true if @string follows the naming rules, false otherwise.
275 */
tomoyo_correct_word2(const char * string,size_t len)276 static bool tomoyo_correct_word2(const char *string, size_t len)
277 {
278 const char *const start = string;
279 bool in_repetition = false;
280 unsigned char c;
281 unsigned char d;
282 unsigned char e;
283 if (!len)
284 goto out;
285 while (len--) {
286 c = *string++;
287 if (c == '\\') {
288 if (!len--)
289 goto out;
290 c = *string++;
291 switch (c) {
292 case '\\': /* "\\" */
293 continue;
294 case '$': /* "\$" */
295 case '+': /* "\+" */
296 case '?': /* "\?" */
297 case '*': /* "\*" */
298 case '@': /* "\@" */
299 case 'x': /* "\x" */
300 case 'X': /* "\X" */
301 case 'a': /* "\a" */
302 case 'A': /* "\A" */
303 case '-': /* "\-" */
304 continue;
305 case '{': /* "/\{" */
306 if (string - 3 < start || *(string - 3) != '/')
307 break;
308 in_repetition = true;
309 continue;
310 case '}': /* "\}/" */
311 if (*string != '/')
312 break;
313 if (!in_repetition)
314 break;
315 in_repetition = false;
316 continue;
317 case '0': /* "\ooo" */
318 case '1':
319 case '2':
320 case '3':
321 if (!len-- || !len--)
322 break;
323 d = *string++;
324 e = *string++;
325 if (d < '0' || d > '7' || e < '0' || e > '7')
326 break;
327 c = tomoyo_make_byte(c, d, e);
328 if (tomoyo_invalid(c))
329 continue; /* pattern is not \000 */
330 }
331 goto out;
332 } else if (in_repetition && c == '/') {
333 goto out;
334 } else if (tomoyo_invalid(c)) {
335 goto out;
336 }
337 }
338 if (in_repetition)
339 goto out;
340 return true;
341 out:
342 return false;
343 }
344
345 /**
346 * tomoyo_correct_word - Validate a string.
347 *
348 * @string: The string to check.
349 *
350 * Check whether the given string follows the naming rules.
351 * Returns true if @string follows the naming rules, false otherwise.
352 */
tomoyo_correct_word(const char * string)353 bool tomoyo_correct_word(const char *string)
354 {
355 return tomoyo_correct_word2(string, strlen(string));
356 }
357
358 /**
359 * tomoyo_correct_path - Validate a pathname.
360 *
361 * @filename: The pathname to check.
362 *
363 * Check whether the given pathname follows the naming rules.
364 * Returns true if @filename follows the naming rules, false otherwise.
365 */
tomoyo_correct_path(const char * filename)366 bool tomoyo_correct_path(const char *filename)
367 {
368 return *filename == '/' && tomoyo_correct_word(filename);
369 }
370
371 /**
372 * tomoyo_correct_domain - Check whether the given domainname follows the naming rules.
373 *
374 * @domainname: The domainname to check.
375 *
376 * Returns true if @domainname follows the naming rules, false otherwise.
377 */
tomoyo_correct_domain(const unsigned char * domainname)378 bool tomoyo_correct_domain(const unsigned char *domainname)
379 {
380 if (!domainname || strncmp(domainname, TOMOYO_ROOT_NAME,
381 TOMOYO_ROOT_NAME_LEN))
382 goto out;
383 domainname += TOMOYO_ROOT_NAME_LEN;
384 if (!*domainname)
385 return true;
386 if (*domainname++ != ' ')
387 goto out;
388 while (1) {
389 const unsigned char *cp = strchr(domainname, ' ');
390 if (!cp)
391 break;
392 if (*domainname != '/' ||
393 !tomoyo_correct_word2(domainname, cp - domainname - 1))
394 goto out;
395 domainname = cp + 1;
396 }
397 return tomoyo_correct_path(domainname);
398 out:
399 return false;
400 }
401
402 /**
403 * tomoyo_domain_def - Check whether the given token can be a domainname.
404 *
405 * @buffer: The token to check.
406 *
407 * Returns true if @buffer possibly be a domainname, false otherwise.
408 */
tomoyo_domain_def(const unsigned char * buffer)409 bool tomoyo_domain_def(const unsigned char *buffer)
410 {
411 return !strncmp(buffer, TOMOYO_ROOT_NAME, TOMOYO_ROOT_NAME_LEN);
412 }
413
414 /**
415 * tomoyo_find_domain - Find a domain by the given name.
416 *
417 * @domainname: The domainname to find.
418 *
419 * Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise.
420 *
421 * Caller holds tomoyo_read_lock().
422 */
tomoyo_find_domain(const char * domainname)423 struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname)
424 {
425 struct tomoyo_domain_info *domain;
426 struct tomoyo_path_info name;
427
428 name.name = domainname;
429 tomoyo_fill_path_info(&name);
430 list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
431 if (!domain->is_deleted &&
432 !tomoyo_pathcmp(&name, domain->domainname))
433 return domain;
434 }
435 return NULL;
436 }
437
438 /**
439 * tomoyo_const_part_length - Evaluate the initial length without a pattern in a token.
440 *
441 * @filename: The string to evaluate.
442 *
443 * Returns the initial length without a pattern in @filename.
444 */
tomoyo_const_part_length(const char * filename)445 static int tomoyo_const_part_length(const char *filename)
446 {
447 char c;
448 int len = 0;
449
450 if (!filename)
451 return 0;
452 while ((c = *filename++) != '\0') {
453 if (c != '\\') {
454 len++;
455 continue;
456 }
457 c = *filename++;
458 switch (c) {
459 case '\\': /* "\\" */
460 len += 2;
461 continue;
462 case '0': /* "\ooo" */
463 case '1':
464 case '2':
465 case '3':
466 c = *filename++;
467 if (c < '0' || c > '7')
468 break;
469 c = *filename++;
470 if (c < '0' || c > '7')
471 break;
472 len += 4;
473 continue;
474 }
475 break;
476 }
477 return len;
478 }
479
480 /**
481 * tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members.
482 *
483 * @ptr: Pointer to "struct tomoyo_path_info" to fill in.
484 *
485 * The caller sets "struct tomoyo_path_info"->name.
486 */
tomoyo_fill_path_info(struct tomoyo_path_info * ptr)487 void tomoyo_fill_path_info(struct tomoyo_path_info *ptr)
488 {
489 const char *name = ptr->name;
490 const int len = strlen(name);
491
492 ptr->const_len = tomoyo_const_part_length(name);
493 ptr->is_dir = len && (name[len - 1] == '/');
494 ptr->is_patterned = (ptr->const_len < len);
495 ptr->hash = full_name_hash(name, len);
496 }
497
498 /**
499 * tomoyo_file_matches_pattern2 - Pattern matching without '/' character and "\-" pattern.
500 *
501 * @filename: The start of string to check.
502 * @filename_end: The end of string to check.
503 * @pattern: The start of pattern to compare.
504 * @pattern_end: The end of pattern to compare.
505 *
506 * Returns true if @filename matches @pattern, false otherwise.
507 */
tomoyo_file_matches_pattern2(const char * filename,const char * filename_end,const char * pattern,const char * pattern_end)508 static bool tomoyo_file_matches_pattern2(const char *filename,
509 const char *filename_end,
510 const char *pattern,
511 const char *pattern_end)
512 {
513 while (filename < filename_end && pattern < pattern_end) {
514 char c;
515 if (*pattern != '\\') {
516 if (*filename++ != *pattern++)
517 return false;
518 continue;
519 }
520 c = *filename;
521 pattern++;
522 switch (*pattern) {
523 int i;
524 int j;
525 case '?':
526 if (c == '/') {
527 return false;
528 } else if (c == '\\') {
529 if (filename[1] == '\\')
530 filename++;
531 else if (tomoyo_byte_range(filename + 1))
532 filename += 3;
533 else
534 return false;
535 }
536 break;
537 case '\\':
538 if (c != '\\')
539 return false;
540 if (*++filename != '\\')
541 return false;
542 break;
543 case '+':
544 if (!isdigit(c))
545 return false;
546 break;
547 case 'x':
548 if (!isxdigit(c))
549 return false;
550 break;
551 case 'a':
552 if (!tomoyo_alphabet_char(c))
553 return false;
554 break;
555 case '0':
556 case '1':
557 case '2':
558 case '3':
559 if (c == '\\' && tomoyo_byte_range(filename + 1)
560 && strncmp(filename + 1, pattern, 3) == 0) {
561 filename += 3;
562 pattern += 2;
563 break;
564 }
565 return false; /* Not matched. */
566 case '*':
567 case '@':
568 for (i = 0; i <= filename_end - filename; i++) {
569 if (tomoyo_file_matches_pattern2(
570 filename + i, filename_end,
571 pattern + 1, pattern_end))
572 return true;
573 c = filename[i];
574 if (c == '.' && *pattern == '@')
575 break;
576 if (c != '\\')
577 continue;
578 if (filename[i + 1] == '\\')
579 i++;
580 else if (tomoyo_byte_range(filename + i + 1))
581 i += 3;
582 else
583 break; /* Bad pattern. */
584 }
585 return false; /* Not matched. */
586 default:
587 j = 0;
588 c = *pattern;
589 if (c == '$') {
590 while (isdigit(filename[j]))
591 j++;
592 } else if (c == 'X') {
593 while (isxdigit(filename[j]))
594 j++;
595 } else if (c == 'A') {
596 while (tomoyo_alphabet_char(filename[j]))
597 j++;
598 }
599 for (i = 1; i <= j; i++) {
600 if (tomoyo_file_matches_pattern2(
601 filename + i, filename_end,
602 pattern + 1, pattern_end))
603 return true;
604 }
605 return false; /* Not matched or bad pattern. */
606 }
607 filename++;
608 pattern++;
609 }
610 while (*pattern == '\\' &&
611 (*(pattern + 1) == '*' || *(pattern + 1) == '@'))
612 pattern += 2;
613 return filename == filename_end && pattern == pattern_end;
614 }
615
616 /**
617 * tomoyo_file_matches_pattern - Pattern matching without '/' character.
618 *
619 * @filename: The start of string to check.
620 * @filename_end: The end of string to check.
621 * @pattern: The start of pattern to compare.
622 * @pattern_end: The end of pattern to compare.
623 *
624 * Returns true if @filename matches @pattern, false otherwise.
625 */
tomoyo_file_matches_pattern(const char * filename,const char * filename_end,const char * pattern,const char * pattern_end)626 static bool tomoyo_file_matches_pattern(const char *filename,
627 const char *filename_end,
628 const char *pattern,
629 const char *pattern_end)
630 {
631 const char *pattern_start = pattern;
632 bool first = true;
633 bool result;
634
635 while (pattern < pattern_end - 1) {
636 /* Split at "\-" pattern. */
637 if (*pattern++ != '\\' || *pattern++ != '-')
638 continue;
639 result = tomoyo_file_matches_pattern2(filename,
640 filename_end,
641 pattern_start,
642 pattern - 2);
643 if (first)
644 result = !result;
645 if (result)
646 return false;
647 first = false;
648 pattern_start = pattern;
649 }
650 result = tomoyo_file_matches_pattern2(filename, filename_end,
651 pattern_start, pattern_end);
652 return first ? result : !result;
653 }
654
655 /**
656 * tomoyo_path_matches_pattern2 - Do pathname pattern matching.
657 *
658 * @f: The start of string to check.
659 * @p: The start of pattern to compare.
660 *
661 * Returns true if @f matches @p, false otherwise.
662 */
tomoyo_path_matches_pattern2(const char * f,const char * p)663 static bool tomoyo_path_matches_pattern2(const char *f, const char *p)
664 {
665 const char *f_delimiter;
666 const char *p_delimiter;
667
668 while (*f && *p) {
669 f_delimiter = strchr(f, '/');
670 if (!f_delimiter)
671 f_delimiter = f + strlen(f);
672 p_delimiter = strchr(p, '/');
673 if (!p_delimiter)
674 p_delimiter = p + strlen(p);
675 if (*p == '\\' && *(p + 1) == '{')
676 goto recursive;
677 if (!tomoyo_file_matches_pattern(f, f_delimiter, p,
678 p_delimiter))
679 return false;
680 f = f_delimiter;
681 if (*f)
682 f++;
683 p = p_delimiter;
684 if (*p)
685 p++;
686 }
687 /* Ignore trailing "\*" and "\@" in @pattern. */
688 while (*p == '\\' &&
689 (*(p + 1) == '*' || *(p + 1) == '@'))
690 p += 2;
691 return !*f && !*p;
692 recursive:
693 /*
694 * The "\{" pattern is permitted only after '/' character.
695 * This guarantees that below "*(p - 1)" is safe.
696 * Also, the "\}" pattern is permitted only before '/' character
697 * so that "\{" + "\}" pair will not break the "\-" operator.
698 */
699 if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' ||
700 *(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\')
701 return false; /* Bad pattern. */
702 do {
703 /* Compare current component with pattern. */
704 if (!tomoyo_file_matches_pattern(f, f_delimiter, p + 2,
705 p_delimiter - 2))
706 break;
707 /* Proceed to next component. */
708 f = f_delimiter;
709 if (!*f)
710 break;
711 f++;
712 /* Continue comparison. */
713 if (tomoyo_path_matches_pattern2(f, p_delimiter + 1))
714 return true;
715 f_delimiter = strchr(f, '/');
716 } while (f_delimiter);
717 return false; /* Not matched. */
718 }
719
720 /**
721 * tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern.
722 *
723 * @filename: The filename to check.
724 * @pattern: The pattern to compare.
725 *
726 * Returns true if matches, false otherwise.
727 *
728 * The following patterns are available.
729 * \\ \ itself.
730 * \ooo Octal representation of a byte.
731 * \* Zero or more repetitions of characters other than '/'.
732 * \@ Zero or more repetitions of characters other than '/' or '.'.
733 * \? 1 byte character other than '/'.
734 * \$ One or more repetitions of decimal digits.
735 * \+ 1 decimal digit.
736 * \X One or more repetitions of hexadecimal digits.
737 * \x 1 hexadecimal digit.
738 * \A One or more repetitions of alphabet characters.
739 * \a 1 alphabet character.
740 *
741 * \- Subtraction operator.
742 *
743 * /\{dir\}/ '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/
744 * /dir/dir/dir/ ).
745 */
tomoyo_path_matches_pattern(const struct tomoyo_path_info * filename,const struct tomoyo_path_info * pattern)746 bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
747 const struct tomoyo_path_info *pattern)
748 {
749 const char *f = filename->name;
750 const char *p = pattern->name;
751 const int len = pattern->const_len;
752
753 /* If @pattern doesn't contain pattern, I can use strcmp(). */
754 if (!pattern->is_patterned)
755 return !tomoyo_pathcmp(filename, pattern);
756 /* Don't compare directory and non-directory. */
757 if (filename->is_dir != pattern->is_dir)
758 return false;
759 /* Compare the initial length without patterns. */
760 if (strncmp(f, p, len))
761 return false;
762 f += len;
763 p += len;
764 return tomoyo_path_matches_pattern2(f, p);
765 }
766
767 /**
768 * tomoyo_get_exe - Get tomoyo_realpath() of current process.
769 *
770 * Returns the tomoyo_realpath() of current process on success, NULL otherwise.
771 *
772 * This function uses kzalloc(), so the caller must call kfree()
773 * if this function didn't return NULL.
774 */
tomoyo_get_exe(void)775 const char *tomoyo_get_exe(void)
776 {
777 struct mm_struct *mm = current->mm;
778 struct vm_area_struct *vma;
779 const char *cp = NULL;
780
781 if (!mm)
782 return NULL;
783 down_read(&mm->mmap_sem);
784 for (vma = mm->mmap; vma; vma = vma->vm_next) {
785 if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file) {
786 cp = tomoyo_realpath_from_path(&vma->vm_file->f_path);
787 break;
788 }
789 }
790 up_read(&mm->mmap_sem);
791 return cp;
792 }
793
794 /**
795 * tomoyo_get_mode - Get MAC mode.
796 *
797 * @profile: Profile number.
798 * @index: Index number of functionality.
799 *
800 * Returns mode.
801 */
tomoyo_get_mode(const u8 profile,const u8 index)802 int tomoyo_get_mode(const u8 profile, const u8 index)
803 {
804 u8 mode;
805 const u8 category = TOMOYO_MAC_CATEGORY_FILE;
806 if (!tomoyo_policy_loaded)
807 return TOMOYO_CONFIG_DISABLED;
808 mode = tomoyo_profile(profile)->config[index];
809 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
810 mode = tomoyo_profile(profile)->config[category];
811 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
812 mode = tomoyo_profile(profile)->default_config;
813 return mode & 3;
814 }
815
816 /**
817 * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members.
818 *
819 * @r: Pointer to "struct tomoyo_request_info" to initialize.
820 * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain().
821 * @index: Index number of functionality.
822 *
823 * Returns mode.
824 */
tomoyo_init_request_info(struct tomoyo_request_info * r,struct tomoyo_domain_info * domain,const u8 index)825 int tomoyo_init_request_info(struct tomoyo_request_info *r,
826 struct tomoyo_domain_info *domain, const u8 index)
827 {
828 u8 profile;
829 memset(r, 0, sizeof(*r));
830 if (!domain)
831 domain = tomoyo_domain();
832 r->domain = domain;
833 profile = domain->profile;
834 r->profile = profile;
835 r->type = index;
836 r->mode = tomoyo_get_mode(profile, index);
837 return r->mode;
838 }
839
840 /**
841 * tomoyo_last_word - Get last component of a line.
842 *
843 * @line: A line.
844 *
845 * Returns the last word of a line.
846 */
tomoyo_last_word(const char * name)847 const char *tomoyo_last_word(const char *name)
848 {
849 const char *cp = strrchr(name, ' ');
850 if (cp)
851 return cp + 1;
852 return name;
853 }
854
855 /**
856 * tomoyo_warn_log - Print warning or error message on console.
857 *
858 * @r: Pointer to "struct tomoyo_request_info".
859 * @fmt: The printf()'s format string, followed by parameters.
860 */
tomoyo_warn_log(struct tomoyo_request_info * r,const char * fmt,...)861 void tomoyo_warn_log(struct tomoyo_request_info *r, const char *fmt, ...)
862 {
863 va_list args;
864 char *buffer;
865 const struct tomoyo_domain_info * const domain = r->domain;
866 const struct tomoyo_profile *profile = tomoyo_profile(domain->profile);
867 switch (r->mode) {
868 case TOMOYO_CONFIG_ENFORCING:
869 if (!profile->enforcing->enforcing_verbose)
870 return;
871 break;
872 case TOMOYO_CONFIG_PERMISSIVE:
873 if (!profile->permissive->permissive_verbose)
874 return;
875 break;
876 case TOMOYO_CONFIG_LEARNING:
877 if (!profile->learning->learning_verbose)
878 return;
879 break;
880 }
881 buffer = kmalloc(4096, GFP_NOFS);
882 if (!buffer)
883 return;
884 va_start(args, fmt);
885 vsnprintf(buffer, 4095, fmt, args);
886 va_end(args);
887 buffer[4095] = '\0';
888 printk(KERN_WARNING "%s: Access %s denied for %s\n",
889 r->mode == TOMOYO_CONFIG_ENFORCING ? "ERROR" : "WARNING", buffer,
890 tomoyo_last_word(domain->domainname->name));
891 kfree(buffer);
892 }
893
894 /**
895 * tomoyo_domain_quota_is_ok - Check for domain's quota.
896 *
897 * @r: Pointer to "struct tomoyo_request_info".
898 *
899 * Returns true if the domain is not exceeded quota, false otherwise.
900 *
901 * Caller holds tomoyo_read_lock().
902 */
tomoyo_domain_quota_is_ok(struct tomoyo_request_info * r)903 bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
904 {
905 unsigned int count = 0;
906 struct tomoyo_domain_info *domain = r->domain;
907 struct tomoyo_acl_info *ptr;
908
909 if (r->mode != TOMOYO_CONFIG_LEARNING)
910 return false;
911 if (!domain)
912 return true;
913 list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
914 if (ptr->is_deleted)
915 continue;
916 switch (ptr->type) {
917 u16 perm;
918 u8 i;
919 case TOMOYO_TYPE_PATH_ACL:
920 perm = container_of(ptr, struct tomoyo_path_acl, head)
921 ->perm;
922 for (i = 0; i < TOMOYO_MAX_PATH_OPERATION; i++)
923 if (perm & (1 << i))
924 count++;
925 if (perm & (1 << TOMOYO_TYPE_READ_WRITE))
926 count -= 2;
927 break;
928 case TOMOYO_TYPE_PATH2_ACL:
929 perm = container_of(ptr, struct tomoyo_path2_acl, head)
930 ->perm;
931 for (i = 0; i < TOMOYO_MAX_PATH2_OPERATION; i++)
932 if (perm & (1 << i))
933 count++;
934 break;
935 case TOMOYO_TYPE_PATH_NUMBER_ACL:
936 perm = container_of(ptr, struct tomoyo_path_number_acl,
937 head)->perm;
938 for (i = 0; i < TOMOYO_MAX_PATH_NUMBER_OPERATION; i++)
939 if (perm & (1 << i))
940 count++;
941 break;
942 case TOMOYO_TYPE_MKDEV_ACL:
943 perm = container_of(ptr, struct tomoyo_mkdev_acl,
944 head)->perm;
945 for (i = 0; i < TOMOYO_MAX_MKDEV_OPERATION; i++)
946 if (perm & (1 << i))
947 count++;
948 break;
949 default:
950 count++;
951 }
952 }
953 if (count < tomoyo_profile(domain->profile)->learning->
954 learning_max_entry)
955 return true;
956 if (!domain->quota_warned) {
957 domain->quota_warned = true;
958 printk(KERN_WARNING "TOMOYO-WARNING: "
959 "Domain '%s' has so many ACLs to hold. "
960 "Stopped learning mode.\n", domain->domainname->name);
961 }
962 return false;
963 }
964