1 /*
2 * security/tomoyo/util.c
3 *
4 * Copyright (C) 2005-2011 NTT DATA CORPORATION
5 */
6
7 #include <linux/slab.h>
8 #include "common.h"
9
10 /* Lock for protecting policy. */
11 DEFINE_MUTEX(tomoyo_policy_lock);
12
13 /* Has /sbin/init started? */
14 bool tomoyo_policy_loaded;
15
16 /*
17 * Mapping table from "enum tomoyo_mac_index" to
18 * "enum tomoyo_mac_category_index".
19 */
20 const u8 tomoyo_index2category[TOMOYO_MAX_MAC_INDEX] = {
21 /* CONFIG::file group */
22 [TOMOYO_MAC_FILE_EXECUTE] = TOMOYO_MAC_CATEGORY_FILE,
23 [TOMOYO_MAC_FILE_OPEN] = TOMOYO_MAC_CATEGORY_FILE,
24 [TOMOYO_MAC_FILE_CREATE] = TOMOYO_MAC_CATEGORY_FILE,
25 [TOMOYO_MAC_FILE_UNLINK] = TOMOYO_MAC_CATEGORY_FILE,
26 [TOMOYO_MAC_FILE_GETATTR] = TOMOYO_MAC_CATEGORY_FILE,
27 [TOMOYO_MAC_FILE_MKDIR] = TOMOYO_MAC_CATEGORY_FILE,
28 [TOMOYO_MAC_FILE_RMDIR] = TOMOYO_MAC_CATEGORY_FILE,
29 [TOMOYO_MAC_FILE_MKFIFO] = TOMOYO_MAC_CATEGORY_FILE,
30 [TOMOYO_MAC_FILE_MKSOCK] = TOMOYO_MAC_CATEGORY_FILE,
31 [TOMOYO_MAC_FILE_TRUNCATE] = TOMOYO_MAC_CATEGORY_FILE,
32 [TOMOYO_MAC_FILE_SYMLINK] = TOMOYO_MAC_CATEGORY_FILE,
33 [TOMOYO_MAC_FILE_MKBLOCK] = TOMOYO_MAC_CATEGORY_FILE,
34 [TOMOYO_MAC_FILE_MKCHAR] = TOMOYO_MAC_CATEGORY_FILE,
35 [TOMOYO_MAC_FILE_LINK] = TOMOYO_MAC_CATEGORY_FILE,
36 [TOMOYO_MAC_FILE_RENAME] = TOMOYO_MAC_CATEGORY_FILE,
37 [TOMOYO_MAC_FILE_CHMOD] = TOMOYO_MAC_CATEGORY_FILE,
38 [TOMOYO_MAC_FILE_CHOWN] = TOMOYO_MAC_CATEGORY_FILE,
39 [TOMOYO_MAC_FILE_CHGRP] = TOMOYO_MAC_CATEGORY_FILE,
40 [TOMOYO_MAC_FILE_IOCTL] = TOMOYO_MAC_CATEGORY_FILE,
41 [TOMOYO_MAC_FILE_CHROOT] = TOMOYO_MAC_CATEGORY_FILE,
42 [TOMOYO_MAC_FILE_MOUNT] = TOMOYO_MAC_CATEGORY_FILE,
43 [TOMOYO_MAC_FILE_UMOUNT] = TOMOYO_MAC_CATEGORY_FILE,
44 [TOMOYO_MAC_FILE_PIVOT_ROOT] = TOMOYO_MAC_CATEGORY_FILE,
45 /* CONFIG::network group */
46 [TOMOYO_MAC_NETWORK_INET_STREAM_BIND] =
47 TOMOYO_MAC_CATEGORY_NETWORK,
48 [TOMOYO_MAC_NETWORK_INET_STREAM_LISTEN] =
49 TOMOYO_MAC_CATEGORY_NETWORK,
50 [TOMOYO_MAC_NETWORK_INET_STREAM_CONNECT] =
51 TOMOYO_MAC_CATEGORY_NETWORK,
52 [TOMOYO_MAC_NETWORK_INET_DGRAM_BIND] =
53 TOMOYO_MAC_CATEGORY_NETWORK,
54 [TOMOYO_MAC_NETWORK_INET_DGRAM_SEND] =
55 TOMOYO_MAC_CATEGORY_NETWORK,
56 [TOMOYO_MAC_NETWORK_INET_RAW_BIND] =
57 TOMOYO_MAC_CATEGORY_NETWORK,
58 [TOMOYO_MAC_NETWORK_INET_RAW_SEND] =
59 TOMOYO_MAC_CATEGORY_NETWORK,
60 [TOMOYO_MAC_NETWORK_UNIX_STREAM_BIND] =
61 TOMOYO_MAC_CATEGORY_NETWORK,
62 [TOMOYO_MAC_NETWORK_UNIX_STREAM_LISTEN] =
63 TOMOYO_MAC_CATEGORY_NETWORK,
64 [TOMOYO_MAC_NETWORK_UNIX_STREAM_CONNECT] =
65 TOMOYO_MAC_CATEGORY_NETWORK,
66 [TOMOYO_MAC_NETWORK_UNIX_DGRAM_BIND] =
67 TOMOYO_MAC_CATEGORY_NETWORK,
68 [TOMOYO_MAC_NETWORK_UNIX_DGRAM_SEND] =
69 TOMOYO_MAC_CATEGORY_NETWORK,
70 [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_BIND] =
71 TOMOYO_MAC_CATEGORY_NETWORK,
72 [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_LISTEN] =
73 TOMOYO_MAC_CATEGORY_NETWORK,
74 [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_CONNECT] =
75 TOMOYO_MAC_CATEGORY_NETWORK,
76 /* CONFIG::misc group */
77 [TOMOYO_MAC_ENVIRON] = TOMOYO_MAC_CATEGORY_MISC,
78 };
79
80 /**
81 * tomoyo_convert_time - Convert time_t to YYYY/MM/DD hh/mm/ss.
82 *
83 * @time: Seconds since 1970/01/01 00:00:00.
84 * @stamp: Pointer to "struct tomoyo_time".
85 *
86 * Returns nothing.
87 *
88 * This function does not handle Y2038 problem.
89 */
tomoyo_convert_time(time_t time,struct tomoyo_time * stamp)90 void tomoyo_convert_time(time_t time, struct tomoyo_time *stamp)
91 {
92 static const u16 tomoyo_eom[2][12] = {
93 { 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
94 { 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
95 };
96 u16 y;
97 u8 m;
98 bool r;
99 stamp->sec = time % 60;
100 time /= 60;
101 stamp->min = time % 60;
102 time /= 60;
103 stamp->hour = time % 24;
104 time /= 24;
105 for (y = 1970; ; y++) {
106 const unsigned short days = (y & 3) ? 365 : 366;
107 if (time < days)
108 break;
109 time -= days;
110 }
111 r = (y & 3) == 0;
112 for (m = 0; m < 11 && time >= tomoyo_eom[r][m]; m++)
113 ;
114 if (m)
115 time -= tomoyo_eom[r][m - 1];
116 stamp->year = y;
117 stamp->month = ++m;
118 stamp->day = ++time;
119 }
120
121 /**
122 * tomoyo_permstr - Find permission keywords.
123 *
124 * @string: String representation for permissions in foo/bar/buz format.
125 * @keyword: Keyword to find from @string/
126 *
127 * Returns ture if @keyword was found in @string, false otherwise.
128 *
129 * This function assumes that strncmp(w1, w2, strlen(w1)) != 0 if w1 != w2.
130 */
tomoyo_permstr(const char * string,const char * keyword)131 bool tomoyo_permstr(const char *string, const char *keyword)
132 {
133 const char *cp = strstr(string, keyword);
134 if (cp)
135 return cp == string || *(cp - 1) == '/';
136 return false;
137 }
138
139 /**
140 * tomoyo_read_token - Read a word from a line.
141 *
142 * @param: Pointer to "struct tomoyo_acl_param".
143 *
144 * Returns a word on success, "" otherwise.
145 *
146 * To allow the caller to skip NULL check, this function returns "" rather than
147 * NULL if there is no more words to read.
148 */
tomoyo_read_token(struct tomoyo_acl_param * param)149 char *tomoyo_read_token(struct tomoyo_acl_param *param)
150 {
151 char *pos = param->data;
152 char *del = strchr(pos, ' ');
153 if (del)
154 *del++ = '\0';
155 else
156 del = pos + strlen(pos);
157 param->data = del;
158 return pos;
159 }
160
161 /**
162 * tomoyo_get_domainname - Read a domainname from a line.
163 *
164 * @param: Pointer to "struct tomoyo_acl_param".
165 *
166 * Returns a domainname on success, NULL otherwise.
167 */
tomoyo_get_domainname(struct tomoyo_acl_param * param)168 const struct tomoyo_path_info *tomoyo_get_domainname
169 (struct tomoyo_acl_param *param)
170 {
171 char *start = param->data;
172 char *pos = start;
173 while (*pos) {
174 if (*pos++ != ' ' || *pos++ == '/')
175 continue;
176 pos -= 2;
177 *pos++ = '\0';
178 break;
179 }
180 param->data = pos;
181 if (tomoyo_correct_domain(start))
182 return tomoyo_get_name(start);
183 return NULL;
184 }
185
186 /**
187 * tomoyo_parse_ulong - Parse an "unsigned long" value.
188 *
189 * @result: Pointer to "unsigned long".
190 * @str: Pointer to string to parse.
191 *
192 * Returns one of values in "enum tomoyo_value_type".
193 *
194 * The @src is updated to point the first character after the value
195 * on success.
196 */
tomoyo_parse_ulong(unsigned long * result,char ** str)197 u8 tomoyo_parse_ulong(unsigned long *result, char **str)
198 {
199 const char *cp = *str;
200 char *ep;
201 int base = 10;
202 if (*cp == '0') {
203 char c = *(cp + 1);
204 if (c == 'x' || c == 'X') {
205 base = 16;
206 cp += 2;
207 } else if (c >= '0' && c <= '7') {
208 base = 8;
209 cp++;
210 }
211 }
212 *result = simple_strtoul(cp, &ep, base);
213 if (cp == ep)
214 return TOMOYO_VALUE_TYPE_INVALID;
215 *str = ep;
216 switch (base) {
217 case 16:
218 return TOMOYO_VALUE_TYPE_HEXADECIMAL;
219 case 8:
220 return TOMOYO_VALUE_TYPE_OCTAL;
221 default:
222 return TOMOYO_VALUE_TYPE_DECIMAL;
223 }
224 }
225
226 /**
227 * tomoyo_print_ulong - Print an "unsigned long" value.
228 *
229 * @buffer: Pointer to buffer.
230 * @buffer_len: Size of @buffer.
231 * @value: An "unsigned long" value.
232 * @type: Type of @value.
233 *
234 * Returns nothing.
235 */
tomoyo_print_ulong(char * buffer,const int buffer_len,const unsigned long value,const u8 type)236 void tomoyo_print_ulong(char *buffer, const int buffer_len,
237 const unsigned long value, const u8 type)
238 {
239 if (type == TOMOYO_VALUE_TYPE_DECIMAL)
240 snprintf(buffer, buffer_len, "%lu", value);
241 else if (type == TOMOYO_VALUE_TYPE_OCTAL)
242 snprintf(buffer, buffer_len, "0%lo", value);
243 else if (type == TOMOYO_VALUE_TYPE_HEXADECIMAL)
244 snprintf(buffer, buffer_len, "0x%lX", value);
245 else
246 snprintf(buffer, buffer_len, "type(%u)", type);
247 }
248
249 /**
250 * tomoyo_parse_name_union - Parse a tomoyo_name_union.
251 *
252 * @param: Pointer to "struct tomoyo_acl_param".
253 * @ptr: Pointer to "struct tomoyo_name_union".
254 *
255 * Returns true on success, false otherwise.
256 */
tomoyo_parse_name_union(struct tomoyo_acl_param * param,struct tomoyo_name_union * ptr)257 bool tomoyo_parse_name_union(struct tomoyo_acl_param *param,
258 struct tomoyo_name_union *ptr)
259 {
260 char *filename;
261 if (param->data[0] == '@') {
262 param->data++;
263 ptr->group = tomoyo_get_group(param, TOMOYO_PATH_GROUP);
264 return ptr->group != NULL;
265 }
266 filename = tomoyo_read_token(param);
267 if (!tomoyo_correct_word(filename))
268 return false;
269 ptr->filename = tomoyo_get_name(filename);
270 return ptr->filename != NULL;
271 }
272
273 /**
274 * tomoyo_parse_number_union - Parse a tomoyo_number_union.
275 *
276 * @param: Pointer to "struct tomoyo_acl_param".
277 * @ptr: Pointer to "struct tomoyo_number_union".
278 *
279 * Returns true on success, false otherwise.
280 */
tomoyo_parse_number_union(struct tomoyo_acl_param * param,struct tomoyo_number_union * ptr)281 bool tomoyo_parse_number_union(struct tomoyo_acl_param *param,
282 struct tomoyo_number_union *ptr)
283 {
284 char *data;
285 u8 type;
286 unsigned long v;
287 memset(ptr, 0, sizeof(*ptr));
288 if (param->data[0] == '@') {
289 param->data++;
290 ptr->group = tomoyo_get_group(param, TOMOYO_NUMBER_GROUP);
291 return ptr->group != NULL;
292 }
293 data = tomoyo_read_token(param);
294 type = tomoyo_parse_ulong(&v, &data);
295 if (type == TOMOYO_VALUE_TYPE_INVALID)
296 return false;
297 ptr->values[0] = v;
298 ptr->value_type[0] = type;
299 if (!*data) {
300 ptr->values[1] = v;
301 ptr->value_type[1] = type;
302 return true;
303 }
304 if (*data++ != '-')
305 return false;
306 type = tomoyo_parse_ulong(&v, &data);
307 if (type == TOMOYO_VALUE_TYPE_INVALID || *data || ptr->values[0] > v)
308 return false;
309 ptr->values[1] = v;
310 ptr->value_type[1] = type;
311 return true;
312 }
313
314 /**
315 * tomoyo_byte_range - Check whether the string is a \ooo style octal value.
316 *
317 * @str: Pointer to the string.
318 *
319 * Returns true if @str is a \ooo style octal value, false otherwise.
320 *
321 * TOMOYO uses \ooo style representation for 0x01 - 0x20 and 0x7F - 0xFF.
322 * This function verifies that \ooo is in valid range.
323 */
tomoyo_byte_range(const char * str)324 static inline bool tomoyo_byte_range(const char *str)
325 {
326 return *str >= '0' && *str++ <= '3' &&
327 *str >= '0' && *str++ <= '7' &&
328 *str >= '0' && *str <= '7';
329 }
330
331 /**
332 * tomoyo_alphabet_char - Check whether the character is an alphabet.
333 *
334 * @c: The character to check.
335 *
336 * Returns true if @c is an alphabet character, false otherwise.
337 */
tomoyo_alphabet_char(const char c)338 static inline bool tomoyo_alphabet_char(const char c)
339 {
340 return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
341 }
342
343 /**
344 * tomoyo_make_byte - Make byte value from three octal characters.
345 *
346 * @c1: The first character.
347 * @c2: The second character.
348 * @c3: The third character.
349 *
350 * Returns byte value.
351 */
tomoyo_make_byte(const u8 c1,const u8 c2,const u8 c3)352 static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
353 {
354 return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
355 }
356
357 /**
358 * tomoyo_valid - Check whether the character is a valid char.
359 *
360 * @c: The character to check.
361 *
362 * Returns true if @c is a valid character, false otherwise.
363 */
tomoyo_valid(const unsigned char c)364 static inline bool tomoyo_valid(const unsigned char c)
365 {
366 return c > ' ' && c < 127;
367 }
368
369 /**
370 * tomoyo_invalid - Check whether the character is an invalid char.
371 *
372 * @c: The character to check.
373 *
374 * Returns true if @c is an invalid character, false otherwise.
375 */
tomoyo_invalid(const unsigned char c)376 static inline bool tomoyo_invalid(const unsigned char c)
377 {
378 return c && (c <= ' ' || c >= 127);
379 }
380
381 /**
382 * tomoyo_str_starts - Check whether the given string starts with the given keyword.
383 *
384 * @src: Pointer to pointer to the string.
385 * @find: Pointer to the keyword.
386 *
387 * Returns true if @src starts with @find, false otherwise.
388 *
389 * The @src is updated to point the first character after the @find
390 * if @src starts with @find.
391 */
tomoyo_str_starts(char ** src,const char * find)392 bool tomoyo_str_starts(char **src, const char *find)
393 {
394 const int len = strlen(find);
395 char *tmp = *src;
396
397 if (strncmp(tmp, find, len))
398 return false;
399 tmp += len;
400 *src = tmp;
401 return true;
402 }
403
404 /**
405 * tomoyo_normalize_line - Format string.
406 *
407 * @buffer: The line to normalize.
408 *
409 * Leading and trailing whitespaces are removed.
410 * Multiple whitespaces are packed into single space.
411 *
412 * Returns nothing.
413 */
tomoyo_normalize_line(unsigned char * buffer)414 void tomoyo_normalize_line(unsigned char *buffer)
415 {
416 unsigned char *sp = buffer;
417 unsigned char *dp = buffer;
418 bool first = true;
419
420 while (tomoyo_invalid(*sp))
421 sp++;
422 while (*sp) {
423 if (!first)
424 *dp++ = ' ';
425 first = false;
426 while (tomoyo_valid(*sp))
427 *dp++ = *sp++;
428 while (tomoyo_invalid(*sp))
429 sp++;
430 }
431 *dp = '\0';
432 }
433
434 /**
435 * tomoyo_correct_word2 - Validate a string.
436 *
437 * @string: The string to check. Maybe non-'\0'-terminated.
438 * @len: Length of @string.
439 *
440 * Check whether the given string follows the naming rules.
441 * Returns true if @string follows the naming rules, false otherwise.
442 */
tomoyo_correct_word2(const char * string,size_t len)443 static bool tomoyo_correct_word2(const char *string, size_t len)
444 {
445 const char *const start = string;
446 bool in_repetition = false;
447 unsigned char c;
448 unsigned char d;
449 unsigned char e;
450 if (!len)
451 goto out;
452 while (len--) {
453 c = *string++;
454 if (c == '\\') {
455 if (!len--)
456 goto out;
457 c = *string++;
458 switch (c) {
459 case '\\': /* "\\" */
460 continue;
461 case '$': /* "\$" */
462 case '+': /* "\+" */
463 case '?': /* "\?" */
464 case '*': /* "\*" */
465 case '@': /* "\@" */
466 case 'x': /* "\x" */
467 case 'X': /* "\X" */
468 case 'a': /* "\a" */
469 case 'A': /* "\A" */
470 case '-': /* "\-" */
471 continue;
472 case '{': /* "/\{" */
473 if (string - 3 < start || *(string - 3) != '/')
474 break;
475 in_repetition = true;
476 continue;
477 case '}': /* "\}/" */
478 if (*string != '/')
479 break;
480 if (!in_repetition)
481 break;
482 in_repetition = false;
483 continue;
484 case '0': /* "\ooo" */
485 case '1':
486 case '2':
487 case '3':
488 if (!len-- || !len--)
489 break;
490 d = *string++;
491 e = *string++;
492 if (d < '0' || d > '7' || e < '0' || e > '7')
493 break;
494 c = tomoyo_make_byte(c, d, e);
495 if (c <= ' ' || c >= 127)
496 continue;
497 }
498 goto out;
499 } else if (in_repetition && c == '/') {
500 goto out;
501 } else if (c <= ' ' || c >= 127) {
502 goto out;
503 }
504 }
505 if (in_repetition)
506 goto out;
507 return true;
508 out:
509 return false;
510 }
511
512 /**
513 * tomoyo_correct_word - Validate a string.
514 *
515 * @string: The string to check.
516 *
517 * Check whether the given string follows the naming rules.
518 * Returns true if @string follows the naming rules, false otherwise.
519 */
tomoyo_correct_word(const char * string)520 bool tomoyo_correct_word(const char *string)
521 {
522 return tomoyo_correct_word2(string, strlen(string));
523 }
524
525 /**
526 * tomoyo_correct_path - Validate a pathname.
527 *
528 * @filename: The pathname to check.
529 *
530 * Check whether the given pathname follows the naming rules.
531 * Returns true if @filename follows the naming rules, false otherwise.
532 */
tomoyo_correct_path(const char * filename)533 bool tomoyo_correct_path(const char *filename)
534 {
535 return *filename == '/' && tomoyo_correct_word(filename);
536 }
537
538 /**
539 * tomoyo_correct_domain - Check whether the given domainname follows the naming rules.
540 *
541 * @domainname: The domainname to check.
542 *
543 * Returns true if @domainname follows the naming rules, false otherwise.
544 */
tomoyo_correct_domain(const unsigned char * domainname)545 bool tomoyo_correct_domain(const unsigned char *domainname)
546 {
547 if (!domainname || !tomoyo_domain_def(domainname))
548 return false;
549 domainname = strchr(domainname, ' ');
550 if (!domainname++)
551 return true;
552 while (1) {
553 const unsigned char *cp = strchr(domainname, ' ');
554 if (!cp)
555 break;
556 if (*domainname != '/' ||
557 !tomoyo_correct_word2(domainname, cp - domainname))
558 return false;
559 domainname = cp + 1;
560 }
561 return tomoyo_correct_path(domainname);
562 }
563
564 /**
565 * tomoyo_domain_def - Check whether the given token can be a domainname.
566 *
567 * @buffer: The token to check.
568 *
569 * Returns true if @buffer possibly be a domainname, false otherwise.
570 */
tomoyo_domain_def(const unsigned char * buffer)571 bool tomoyo_domain_def(const unsigned char *buffer)
572 {
573 const unsigned char *cp;
574 int len;
575 if (*buffer != '<')
576 return false;
577 cp = strchr(buffer, ' ');
578 if (!cp)
579 len = strlen(buffer);
580 else
581 len = cp - buffer;
582 if (buffer[len - 1] != '>' ||
583 !tomoyo_correct_word2(buffer + 1, len - 2))
584 return false;
585 return true;
586 }
587
588 /**
589 * tomoyo_find_domain - Find a domain by the given name.
590 *
591 * @domainname: The domainname to find.
592 *
593 * Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise.
594 *
595 * Caller holds tomoyo_read_lock().
596 */
tomoyo_find_domain(const char * domainname)597 struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname)
598 {
599 struct tomoyo_domain_info *domain;
600 struct tomoyo_path_info name;
601
602 name.name = domainname;
603 tomoyo_fill_path_info(&name);
604 list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
605 if (!domain->is_deleted &&
606 !tomoyo_pathcmp(&name, domain->domainname))
607 return domain;
608 }
609 return NULL;
610 }
611
612 /**
613 * tomoyo_const_part_length - Evaluate the initial length without a pattern in a token.
614 *
615 * @filename: The string to evaluate.
616 *
617 * Returns the initial length without a pattern in @filename.
618 */
tomoyo_const_part_length(const char * filename)619 static int tomoyo_const_part_length(const char *filename)
620 {
621 char c;
622 int len = 0;
623
624 if (!filename)
625 return 0;
626 while ((c = *filename++) != '\0') {
627 if (c != '\\') {
628 len++;
629 continue;
630 }
631 c = *filename++;
632 switch (c) {
633 case '\\': /* "\\" */
634 len += 2;
635 continue;
636 case '0': /* "\ooo" */
637 case '1':
638 case '2':
639 case '3':
640 c = *filename++;
641 if (c < '0' || c > '7')
642 break;
643 c = *filename++;
644 if (c < '0' || c > '7')
645 break;
646 len += 4;
647 continue;
648 }
649 break;
650 }
651 return len;
652 }
653
654 /**
655 * tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members.
656 *
657 * @ptr: Pointer to "struct tomoyo_path_info" to fill in.
658 *
659 * The caller sets "struct tomoyo_path_info"->name.
660 */
tomoyo_fill_path_info(struct tomoyo_path_info * ptr)661 void tomoyo_fill_path_info(struct tomoyo_path_info *ptr)
662 {
663 const char *name = ptr->name;
664 const int len = strlen(name);
665
666 ptr->const_len = tomoyo_const_part_length(name);
667 ptr->is_dir = len && (name[len - 1] == '/');
668 ptr->is_patterned = (ptr->const_len < len);
669 ptr->hash = full_name_hash(name, len);
670 }
671
672 /**
673 * tomoyo_file_matches_pattern2 - Pattern matching without '/' character and "\-" pattern.
674 *
675 * @filename: The start of string to check.
676 * @filename_end: The end of string to check.
677 * @pattern: The start of pattern to compare.
678 * @pattern_end: The end of pattern to compare.
679 *
680 * Returns true if @filename matches @pattern, false otherwise.
681 */
tomoyo_file_matches_pattern2(const char * filename,const char * filename_end,const char * pattern,const char * pattern_end)682 static bool tomoyo_file_matches_pattern2(const char *filename,
683 const char *filename_end,
684 const char *pattern,
685 const char *pattern_end)
686 {
687 while (filename < filename_end && pattern < pattern_end) {
688 char c;
689 if (*pattern != '\\') {
690 if (*filename++ != *pattern++)
691 return false;
692 continue;
693 }
694 c = *filename;
695 pattern++;
696 switch (*pattern) {
697 int i;
698 int j;
699 case '?':
700 if (c == '/') {
701 return false;
702 } else if (c == '\\') {
703 if (filename[1] == '\\')
704 filename++;
705 else if (tomoyo_byte_range(filename + 1))
706 filename += 3;
707 else
708 return false;
709 }
710 break;
711 case '\\':
712 if (c != '\\')
713 return false;
714 if (*++filename != '\\')
715 return false;
716 break;
717 case '+':
718 if (!isdigit(c))
719 return false;
720 break;
721 case 'x':
722 if (!isxdigit(c))
723 return false;
724 break;
725 case 'a':
726 if (!tomoyo_alphabet_char(c))
727 return false;
728 break;
729 case '0':
730 case '1':
731 case '2':
732 case '3':
733 if (c == '\\' && tomoyo_byte_range(filename + 1)
734 && strncmp(filename + 1, pattern, 3) == 0) {
735 filename += 3;
736 pattern += 2;
737 break;
738 }
739 return false; /* Not matched. */
740 case '*':
741 case '@':
742 for (i = 0; i <= filename_end - filename; i++) {
743 if (tomoyo_file_matches_pattern2(
744 filename + i, filename_end,
745 pattern + 1, pattern_end))
746 return true;
747 c = filename[i];
748 if (c == '.' && *pattern == '@')
749 break;
750 if (c != '\\')
751 continue;
752 if (filename[i + 1] == '\\')
753 i++;
754 else if (tomoyo_byte_range(filename + i + 1))
755 i += 3;
756 else
757 break; /* Bad pattern. */
758 }
759 return false; /* Not matched. */
760 default:
761 j = 0;
762 c = *pattern;
763 if (c == '$') {
764 while (isdigit(filename[j]))
765 j++;
766 } else if (c == 'X') {
767 while (isxdigit(filename[j]))
768 j++;
769 } else if (c == 'A') {
770 while (tomoyo_alphabet_char(filename[j]))
771 j++;
772 }
773 for (i = 1; i <= j; i++) {
774 if (tomoyo_file_matches_pattern2(
775 filename + i, filename_end,
776 pattern + 1, pattern_end))
777 return true;
778 }
779 return false; /* Not matched or bad pattern. */
780 }
781 filename++;
782 pattern++;
783 }
784 while (*pattern == '\\' &&
785 (*(pattern + 1) == '*' || *(pattern + 1) == '@'))
786 pattern += 2;
787 return filename == filename_end && pattern == pattern_end;
788 }
789
790 /**
791 * tomoyo_file_matches_pattern - Pattern matching without '/' character.
792 *
793 * @filename: The start of string to check.
794 * @filename_end: The end of string to check.
795 * @pattern: The start of pattern to compare.
796 * @pattern_end: The end of pattern to compare.
797 *
798 * Returns true if @filename matches @pattern, false otherwise.
799 */
tomoyo_file_matches_pattern(const char * filename,const char * filename_end,const char * pattern,const char * pattern_end)800 static bool tomoyo_file_matches_pattern(const char *filename,
801 const char *filename_end,
802 const char *pattern,
803 const char *pattern_end)
804 {
805 const char *pattern_start = pattern;
806 bool first = true;
807 bool result;
808
809 while (pattern < pattern_end - 1) {
810 /* Split at "\-" pattern. */
811 if (*pattern++ != '\\' || *pattern++ != '-')
812 continue;
813 result = tomoyo_file_matches_pattern2(filename,
814 filename_end,
815 pattern_start,
816 pattern - 2);
817 if (first)
818 result = !result;
819 if (result)
820 return false;
821 first = false;
822 pattern_start = pattern;
823 }
824 result = tomoyo_file_matches_pattern2(filename, filename_end,
825 pattern_start, pattern_end);
826 return first ? result : !result;
827 }
828
829 /**
830 * tomoyo_path_matches_pattern2 - Do pathname pattern matching.
831 *
832 * @f: The start of string to check.
833 * @p: The start of pattern to compare.
834 *
835 * Returns true if @f matches @p, false otherwise.
836 */
tomoyo_path_matches_pattern2(const char * f,const char * p)837 static bool tomoyo_path_matches_pattern2(const char *f, const char *p)
838 {
839 const char *f_delimiter;
840 const char *p_delimiter;
841
842 while (*f && *p) {
843 f_delimiter = strchr(f, '/');
844 if (!f_delimiter)
845 f_delimiter = f + strlen(f);
846 p_delimiter = strchr(p, '/');
847 if (!p_delimiter)
848 p_delimiter = p + strlen(p);
849 if (*p == '\\' && *(p + 1) == '{')
850 goto recursive;
851 if (!tomoyo_file_matches_pattern(f, f_delimiter, p,
852 p_delimiter))
853 return false;
854 f = f_delimiter;
855 if (*f)
856 f++;
857 p = p_delimiter;
858 if (*p)
859 p++;
860 }
861 /* Ignore trailing "\*" and "\@" in @pattern. */
862 while (*p == '\\' &&
863 (*(p + 1) == '*' || *(p + 1) == '@'))
864 p += 2;
865 return !*f && !*p;
866 recursive:
867 /*
868 * The "\{" pattern is permitted only after '/' character.
869 * This guarantees that below "*(p - 1)" is safe.
870 * Also, the "\}" pattern is permitted only before '/' character
871 * so that "\{" + "\}" pair will not break the "\-" operator.
872 */
873 if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' ||
874 *(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\')
875 return false; /* Bad pattern. */
876 do {
877 /* Compare current component with pattern. */
878 if (!tomoyo_file_matches_pattern(f, f_delimiter, p + 2,
879 p_delimiter - 2))
880 break;
881 /* Proceed to next component. */
882 f = f_delimiter;
883 if (!*f)
884 break;
885 f++;
886 /* Continue comparison. */
887 if (tomoyo_path_matches_pattern2(f, p_delimiter + 1))
888 return true;
889 f_delimiter = strchr(f, '/');
890 } while (f_delimiter);
891 return false; /* Not matched. */
892 }
893
894 /**
895 * tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern.
896 *
897 * @filename: The filename to check.
898 * @pattern: The pattern to compare.
899 *
900 * Returns true if matches, false otherwise.
901 *
902 * The following patterns are available.
903 * \\ \ itself.
904 * \ooo Octal representation of a byte.
905 * \* Zero or more repetitions of characters other than '/'.
906 * \@ Zero or more repetitions of characters other than '/' or '.'.
907 * \? 1 byte character other than '/'.
908 * \$ One or more repetitions of decimal digits.
909 * \+ 1 decimal digit.
910 * \X One or more repetitions of hexadecimal digits.
911 * \x 1 hexadecimal digit.
912 * \A One or more repetitions of alphabet characters.
913 * \a 1 alphabet character.
914 *
915 * \- Subtraction operator.
916 *
917 * /\{dir\}/ '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/
918 * /dir/dir/dir/ ).
919 */
tomoyo_path_matches_pattern(const struct tomoyo_path_info * filename,const struct tomoyo_path_info * pattern)920 bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
921 const struct tomoyo_path_info *pattern)
922 {
923 const char *f = filename->name;
924 const char *p = pattern->name;
925 const int len = pattern->const_len;
926
927 /* If @pattern doesn't contain pattern, I can use strcmp(). */
928 if (!pattern->is_patterned)
929 return !tomoyo_pathcmp(filename, pattern);
930 /* Don't compare directory and non-directory. */
931 if (filename->is_dir != pattern->is_dir)
932 return false;
933 /* Compare the initial length without patterns. */
934 if (strncmp(f, p, len))
935 return false;
936 f += len;
937 p += len;
938 return tomoyo_path_matches_pattern2(f, p);
939 }
940
941 /**
942 * tomoyo_get_exe - Get tomoyo_realpath() of current process.
943 *
944 * Returns the tomoyo_realpath() of current process on success, NULL otherwise.
945 *
946 * This function uses kzalloc(), so the caller must call kfree()
947 * if this function didn't return NULL.
948 */
tomoyo_get_exe(void)949 const char *tomoyo_get_exe(void)
950 {
951 struct mm_struct *mm = current->mm;
952 const char *cp = NULL;
953
954 if (!mm)
955 return NULL;
956 down_read(&mm->mmap_sem);
957 if (mm->exe_file)
958 cp = tomoyo_realpath_from_path(&mm->exe_file->f_path);
959 up_read(&mm->mmap_sem);
960 return cp;
961 }
962
963 /**
964 * tomoyo_get_mode - Get MAC mode.
965 *
966 * @ns: Pointer to "struct tomoyo_policy_namespace".
967 * @profile: Profile number.
968 * @index: Index number of functionality.
969 *
970 * Returns mode.
971 */
tomoyo_get_mode(const struct tomoyo_policy_namespace * ns,const u8 profile,const u8 index)972 int tomoyo_get_mode(const struct tomoyo_policy_namespace *ns, const u8 profile,
973 const u8 index)
974 {
975 u8 mode;
976 struct tomoyo_profile *p;
977
978 if (!tomoyo_policy_loaded)
979 return TOMOYO_CONFIG_DISABLED;
980 p = tomoyo_profile(ns, profile);
981 mode = p->config[index];
982 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
983 mode = p->config[tomoyo_index2category[index]
984 + TOMOYO_MAX_MAC_INDEX];
985 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
986 mode = p->default_config;
987 return mode & 3;
988 }
989
990 /**
991 * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members.
992 *
993 * @r: Pointer to "struct tomoyo_request_info" to initialize.
994 * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain().
995 * @index: Index number of functionality.
996 *
997 * Returns mode.
998 */
tomoyo_init_request_info(struct tomoyo_request_info * r,struct tomoyo_domain_info * domain,const u8 index)999 int tomoyo_init_request_info(struct tomoyo_request_info *r,
1000 struct tomoyo_domain_info *domain, const u8 index)
1001 {
1002 u8 profile;
1003 memset(r, 0, sizeof(*r));
1004 if (!domain)
1005 domain = tomoyo_domain();
1006 r->domain = domain;
1007 profile = domain->profile;
1008 r->profile = profile;
1009 r->type = index;
1010 r->mode = tomoyo_get_mode(domain->ns, profile, index);
1011 return r->mode;
1012 }
1013
1014 /**
1015 * tomoyo_domain_quota_is_ok - Check for domain's quota.
1016 *
1017 * @r: Pointer to "struct tomoyo_request_info".
1018 *
1019 * Returns true if the domain is not exceeded quota, false otherwise.
1020 *
1021 * Caller holds tomoyo_read_lock().
1022 */
tomoyo_domain_quota_is_ok(struct tomoyo_request_info * r)1023 bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
1024 {
1025 unsigned int count = 0;
1026 struct tomoyo_domain_info *domain = r->domain;
1027 struct tomoyo_acl_info *ptr;
1028
1029 if (r->mode != TOMOYO_CONFIG_LEARNING)
1030 return false;
1031 if (!domain)
1032 return true;
1033 list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
1034 u16 perm;
1035 u8 i;
1036 if (ptr->is_deleted)
1037 continue;
1038 switch (ptr->type) {
1039 case TOMOYO_TYPE_PATH_ACL:
1040 perm = container_of(ptr, struct tomoyo_path_acl, head)
1041 ->perm;
1042 break;
1043 case TOMOYO_TYPE_PATH2_ACL:
1044 perm = container_of(ptr, struct tomoyo_path2_acl, head)
1045 ->perm;
1046 break;
1047 case TOMOYO_TYPE_PATH_NUMBER_ACL:
1048 perm = container_of(ptr, struct tomoyo_path_number_acl,
1049 head)->perm;
1050 break;
1051 case TOMOYO_TYPE_MKDEV_ACL:
1052 perm = container_of(ptr, struct tomoyo_mkdev_acl,
1053 head)->perm;
1054 break;
1055 case TOMOYO_TYPE_INET_ACL:
1056 perm = container_of(ptr, struct tomoyo_inet_acl,
1057 head)->perm;
1058 break;
1059 case TOMOYO_TYPE_UNIX_ACL:
1060 perm = container_of(ptr, struct tomoyo_unix_acl,
1061 head)->perm;
1062 break;
1063 case TOMOYO_TYPE_MANUAL_TASK_ACL:
1064 perm = 0;
1065 break;
1066 default:
1067 perm = 1;
1068 }
1069 for (i = 0; i < 16; i++)
1070 if (perm & (1 << i))
1071 count++;
1072 }
1073 if (count < tomoyo_profile(domain->ns, domain->profile)->
1074 pref[TOMOYO_PREF_MAX_LEARNING_ENTRY])
1075 return true;
1076 if (!domain->flags[TOMOYO_DIF_QUOTA_WARNED]) {
1077 domain->flags[TOMOYO_DIF_QUOTA_WARNED] = true;
1078 /* r->granted = false; */
1079 tomoyo_write_log(r, "%s", tomoyo_dif[TOMOYO_DIF_QUOTA_WARNED]);
1080 printk(KERN_WARNING "WARNING: "
1081 "Domain '%s' has too many ACLs to hold. "
1082 "Stopped learning mode.\n", domain->domainname->name);
1083 }
1084 return false;
1085 }
1086