1// SPDX-License-Identifier: GPL-2.0
2/*
3 * security/tomoyo/util.c
4 *
5 * Copyright (C) 2005-2011 NTT DATA CORPORATION
6 */
7
8#include <linux/slab.h>
9#include <linux/rculist.h>
10
11#include "common.h"
12
13/* Lock for protecting policy. */
14DEFINE_MUTEX(tomoyo_policy_lock);
15
16/* Has /sbin/init started? */
17bool tomoyo_policy_loaded;
18
19/*
20 * Mapping table from "enum tomoyo_mac_index" to
21 * "enum tomoyo_mac_category_index".
22 */
23const u8 tomoyo_index2category[TOMOYO_MAX_MAC_INDEX] = {
24 /* CONFIG::file group */
25 [TOMOYO_MAC_FILE_EXECUTE] = TOMOYO_MAC_CATEGORY_FILE,
26 [TOMOYO_MAC_FILE_OPEN] = TOMOYO_MAC_CATEGORY_FILE,
27 [TOMOYO_MAC_FILE_CREATE] = TOMOYO_MAC_CATEGORY_FILE,
28 [TOMOYO_MAC_FILE_UNLINK] = TOMOYO_MAC_CATEGORY_FILE,
29 [TOMOYO_MAC_FILE_GETATTR] = TOMOYO_MAC_CATEGORY_FILE,
30 [TOMOYO_MAC_FILE_MKDIR] = TOMOYO_MAC_CATEGORY_FILE,
31 [TOMOYO_MAC_FILE_RMDIR] = TOMOYO_MAC_CATEGORY_FILE,
32 [TOMOYO_MAC_FILE_MKFIFO] = TOMOYO_MAC_CATEGORY_FILE,
33 [TOMOYO_MAC_FILE_MKSOCK] = TOMOYO_MAC_CATEGORY_FILE,
34 [TOMOYO_MAC_FILE_TRUNCATE] = TOMOYO_MAC_CATEGORY_FILE,
35 [TOMOYO_MAC_FILE_SYMLINK] = TOMOYO_MAC_CATEGORY_FILE,
36 [TOMOYO_MAC_FILE_MKBLOCK] = TOMOYO_MAC_CATEGORY_FILE,
37 [TOMOYO_MAC_FILE_MKCHAR] = TOMOYO_MAC_CATEGORY_FILE,
38 [TOMOYO_MAC_FILE_LINK] = TOMOYO_MAC_CATEGORY_FILE,
39 [TOMOYO_MAC_FILE_RENAME] = TOMOYO_MAC_CATEGORY_FILE,
40 [TOMOYO_MAC_FILE_CHMOD] = TOMOYO_MAC_CATEGORY_FILE,
41 [TOMOYO_MAC_FILE_CHOWN] = TOMOYO_MAC_CATEGORY_FILE,
42 [TOMOYO_MAC_FILE_CHGRP] = TOMOYO_MAC_CATEGORY_FILE,
43 [TOMOYO_MAC_FILE_IOCTL] = TOMOYO_MAC_CATEGORY_FILE,
44 [TOMOYO_MAC_FILE_CHROOT] = TOMOYO_MAC_CATEGORY_FILE,
45 [TOMOYO_MAC_FILE_MOUNT] = TOMOYO_MAC_CATEGORY_FILE,
46 [TOMOYO_MAC_FILE_UMOUNT] = TOMOYO_MAC_CATEGORY_FILE,
47 [TOMOYO_MAC_FILE_PIVOT_ROOT] = TOMOYO_MAC_CATEGORY_FILE,
48 /* CONFIG::network group */
49 [TOMOYO_MAC_NETWORK_INET_STREAM_BIND] =
50 TOMOYO_MAC_CATEGORY_NETWORK,
51 [TOMOYO_MAC_NETWORK_INET_STREAM_LISTEN] =
52 TOMOYO_MAC_CATEGORY_NETWORK,
53 [TOMOYO_MAC_NETWORK_INET_STREAM_CONNECT] =
54 TOMOYO_MAC_CATEGORY_NETWORK,
55 [TOMOYO_MAC_NETWORK_INET_DGRAM_BIND] =
56 TOMOYO_MAC_CATEGORY_NETWORK,
57 [TOMOYO_MAC_NETWORK_INET_DGRAM_SEND] =
58 TOMOYO_MAC_CATEGORY_NETWORK,
59 [TOMOYO_MAC_NETWORK_INET_RAW_BIND] =
60 TOMOYO_MAC_CATEGORY_NETWORK,
61 [TOMOYO_MAC_NETWORK_INET_RAW_SEND] =
62 TOMOYO_MAC_CATEGORY_NETWORK,
63 [TOMOYO_MAC_NETWORK_UNIX_STREAM_BIND] =
64 TOMOYO_MAC_CATEGORY_NETWORK,
65 [TOMOYO_MAC_NETWORK_UNIX_STREAM_LISTEN] =
66 TOMOYO_MAC_CATEGORY_NETWORK,
67 [TOMOYO_MAC_NETWORK_UNIX_STREAM_CONNECT] =
68 TOMOYO_MAC_CATEGORY_NETWORK,
69 [TOMOYO_MAC_NETWORK_UNIX_DGRAM_BIND] =
70 TOMOYO_MAC_CATEGORY_NETWORK,
71 [TOMOYO_MAC_NETWORK_UNIX_DGRAM_SEND] =
72 TOMOYO_MAC_CATEGORY_NETWORK,
73 [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_BIND] =
74 TOMOYO_MAC_CATEGORY_NETWORK,
75 [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_LISTEN] =
76 TOMOYO_MAC_CATEGORY_NETWORK,
77 [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_CONNECT] =
78 TOMOYO_MAC_CATEGORY_NETWORK,
79 /* CONFIG::misc group */
80 [TOMOYO_MAC_ENVIRON] = TOMOYO_MAC_CATEGORY_MISC,
81};
82
83/**
84 * tomoyo_convert_time - Convert time_t to YYYY/MM/DD hh/mm/ss.
85 *
86 * @time64: Seconds since 1970/01/01 00:00:00.
87 * @stamp: Pointer to "struct tomoyo_time".
88 *
89 * Returns nothing.
90 */
91void tomoyo_convert_time(time64_t time64, struct tomoyo_time *stamp)
92{
93 struct tm tm;
94
95 time64_to_tm(totalsecs: time64, offset: 0, result: &tm);
96 stamp->sec = tm.tm_sec;
97 stamp->min = tm.tm_min;
98 stamp->hour = tm.tm_hour;
99 stamp->day = tm.tm_mday;
100 stamp->month = tm.tm_mon + 1;
101 stamp->year = tm.tm_year + 1900;
102}
103
104/**
105 * tomoyo_permstr - Find permission keywords.
106 *
107 * @string: String representation for permissions in foo/bar/buz format.
108 * @keyword: Keyword to find from @string/
109 *
110 * Returns true if @keyword was found in @string, false otherwise.
111 *
112 * This function assumes that strncmp(w1, w2, strlen(w1)) != 0 if w1 != w2.
113 */
114bool tomoyo_permstr(const char *string, const char *keyword)
115{
116 const char *cp = strstr(string, keyword);
117
118 if (cp)
119 return cp == string || *(cp - 1) == '/';
120 return false;
121}
122
123/**
124 * tomoyo_read_token - Read a word from a line.
125 *
126 * @param: Pointer to "struct tomoyo_acl_param".
127 *
128 * Returns a word on success, "" otherwise.
129 *
130 * To allow the caller to skip NULL check, this function returns "" rather than
131 * NULL if there is no more words to read.
132 */
133char *tomoyo_read_token(struct tomoyo_acl_param *param)
134{
135 char *pos = param->data;
136 char *del = strchr(pos, ' ');
137
138 if (del)
139 *del++ = '\0';
140 else
141 del = pos + strlen(pos);
142 param->data = del;
143 return pos;
144}
145
146static bool tomoyo_correct_path2(const char *filename, const size_t len);
147
148/**
149 * tomoyo_get_domainname - Read a domainname from a line.
150 *
151 * @param: Pointer to "struct tomoyo_acl_param".
152 *
153 * Returns a domainname on success, NULL otherwise.
154 */
155const struct tomoyo_path_info *tomoyo_get_domainname
156(struct tomoyo_acl_param *param)
157{
158 char *start = param->data;
159 char *pos = start;
160
161 while (*pos) {
162 if (*pos++ != ' ' ||
163 tomoyo_correct_path2(filename: pos, len: strchrnul(pos, ' ') - pos))
164 continue;
165 *(pos - 1) = '\0';
166 break;
167 }
168 param->data = pos;
169 if (tomoyo_correct_domain(domainname: start))
170 return tomoyo_get_name(name: start);
171 return NULL;
172}
173
174/**
175 * tomoyo_parse_ulong - Parse an "unsigned long" value.
176 *
177 * @result: Pointer to "unsigned long".
178 * @str: Pointer to string to parse.
179 *
180 * Returns one of values in "enum tomoyo_value_type".
181 *
182 * The @src is updated to point the first character after the value
183 * on success.
184 */
185u8 tomoyo_parse_ulong(unsigned long *result, char **str)
186{
187 const char *cp = *str;
188 char *ep;
189 int base = 10;
190
191 if (*cp == '0') {
192 char c = *(cp + 1);
193
194 if (c == 'x' || c == 'X') {
195 base = 16;
196 cp += 2;
197 } else if (c >= '0' && c <= '7') {
198 base = 8;
199 cp++;
200 }
201 }
202 *result = simple_strtoul(cp, &ep, base);
203 if (cp == ep)
204 return TOMOYO_VALUE_TYPE_INVALID;
205 *str = ep;
206 switch (base) {
207 case 16:
208 return TOMOYO_VALUE_TYPE_HEXADECIMAL;
209 case 8:
210 return TOMOYO_VALUE_TYPE_OCTAL;
211 default:
212 return TOMOYO_VALUE_TYPE_DECIMAL;
213 }
214}
215
216/**
217 * tomoyo_print_ulong - Print an "unsigned long" value.
218 *
219 * @buffer: Pointer to buffer.
220 * @buffer_len: Size of @buffer.
221 * @value: An "unsigned long" value.
222 * @type: Type of @value.
223 *
224 * Returns nothing.
225 */
226void tomoyo_print_ulong(char *buffer, const int buffer_len,
227 const unsigned long value, const u8 type)
228{
229 if (type == TOMOYO_VALUE_TYPE_DECIMAL)
230 snprintf(buf: buffer, size: buffer_len, fmt: "%lu", value);
231 else if (type == TOMOYO_VALUE_TYPE_OCTAL)
232 snprintf(buf: buffer, size: buffer_len, fmt: "0%lo", value);
233 else if (type == TOMOYO_VALUE_TYPE_HEXADECIMAL)
234 snprintf(buf: buffer, size: buffer_len, fmt: "0x%lX", value);
235 else
236 snprintf(buf: buffer, size: buffer_len, fmt: "type(%u)", type);
237}
238
239/**
240 * tomoyo_parse_name_union - Parse a tomoyo_name_union.
241 *
242 * @param: Pointer to "struct tomoyo_acl_param".
243 * @ptr: Pointer to "struct tomoyo_name_union".
244 *
245 * Returns true on success, false otherwise.
246 */
247bool tomoyo_parse_name_union(struct tomoyo_acl_param *param,
248 struct tomoyo_name_union *ptr)
249{
250 char *filename;
251
252 if (param->data[0] == '@') {
253 param->data++;
254 ptr->group = tomoyo_get_group(param, idx: TOMOYO_PATH_GROUP);
255 return ptr->group != NULL;
256 }
257 filename = tomoyo_read_token(param);
258 if (!tomoyo_correct_word(string: filename))
259 return false;
260 ptr->filename = tomoyo_get_name(name: filename);
261 return ptr->filename != NULL;
262}
263
264/**
265 * tomoyo_parse_number_union - Parse a tomoyo_number_union.
266 *
267 * @param: Pointer to "struct tomoyo_acl_param".
268 * @ptr: Pointer to "struct tomoyo_number_union".
269 *
270 * Returns true on success, false otherwise.
271 */
272bool tomoyo_parse_number_union(struct tomoyo_acl_param *param,
273 struct tomoyo_number_union *ptr)
274{
275 char *data;
276 u8 type;
277 unsigned long v;
278
279 memset(ptr, 0, sizeof(*ptr));
280 if (param->data[0] == '@') {
281 param->data++;
282 ptr->group = tomoyo_get_group(param, idx: TOMOYO_NUMBER_GROUP);
283 return ptr->group != NULL;
284 }
285 data = tomoyo_read_token(param);
286 type = tomoyo_parse_ulong(result: &v, str: &data);
287 if (type == TOMOYO_VALUE_TYPE_INVALID)
288 return false;
289 ptr->values[0] = v;
290 ptr->value_type[0] = type;
291 if (!*data) {
292 ptr->values[1] = v;
293 ptr->value_type[1] = type;
294 return true;
295 }
296 if (*data++ != '-')
297 return false;
298 type = tomoyo_parse_ulong(result: &v, str: &data);
299 if (type == TOMOYO_VALUE_TYPE_INVALID || *data || ptr->values[0] > v)
300 return false;
301 ptr->values[1] = v;
302 ptr->value_type[1] = type;
303 return true;
304}
305
306/**
307 * tomoyo_byte_range - Check whether the string is a \ooo style octal value.
308 *
309 * @str: Pointer to the string.
310 *
311 * Returns true if @str is a \ooo style octal value, false otherwise.
312 *
313 * TOMOYO uses \ooo style representation for 0x01 - 0x20 and 0x7F - 0xFF.
314 * This function verifies that \ooo is in valid range.
315 */
316static inline bool tomoyo_byte_range(const char *str)
317{
318 return *str >= '0' && *str++ <= '3' &&
319 *str >= '0' && *str++ <= '7' &&
320 *str >= '0' && *str <= '7';
321}
322
323/**
324 * tomoyo_alphabet_char - Check whether the character is an alphabet.
325 *
326 * @c: The character to check.
327 *
328 * Returns true if @c is an alphabet character, false otherwise.
329 */
330static inline bool tomoyo_alphabet_char(const char c)
331{
332 return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
333}
334
335/**
336 * tomoyo_make_byte - Make byte value from three octal characters.
337 *
338 * @c1: The first character.
339 * @c2: The second character.
340 * @c3: The third character.
341 *
342 * Returns byte value.
343 */
344static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
345{
346 return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
347}
348
349/**
350 * tomoyo_valid - Check whether the character is a valid char.
351 *
352 * @c: The character to check.
353 *
354 * Returns true if @c is a valid character, false otherwise.
355 */
356static inline bool tomoyo_valid(const unsigned char c)
357{
358 return c > ' ' && c < 127;
359}
360
361/**
362 * tomoyo_invalid - Check whether the character is an invalid char.
363 *
364 * @c: The character to check.
365 *
366 * Returns true if @c is an invalid character, false otherwise.
367 */
368static inline bool tomoyo_invalid(const unsigned char c)
369{
370 return c && (c <= ' ' || c >= 127);
371}
372
373/**
374 * tomoyo_str_starts - Check whether the given string starts with the given keyword.
375 *
376 * @src: Pointer to pointer to the string.
377 * @find: Pointer to the keyword.
378 *
379 * Returns true if @src starts with @find, false otherwise.
380 *
381 * The @src is updated to point the first character after the @find
382 * if @src starts with @find.
383 */
384bool tomoyo_str_starts(char **src, const char *find)
385{
386 const int len = strlen(find);
387 char *tmp = *src;
388
389 if (strncmp(tmp, find, len))
390 return false;
391 tmp += len;
392 *src = tmp;
393 return true;
394}
395
396/**
397 * tomoyo_normalize_line - Format string.
398 *
399 * @buffer: The line to normalize.
400 *
401 * Leading and trailing whitespaces are removed.
402 * Multiple whitespaces are packed into single space.
403 *
404 * Returns nothing.
405 */
406void tomoyo_normalize_line(unsigned char *buffer)
407{
408 unsigned char *sp = buffer;
409 unsigned char *dp = buffer;
410 bool first = true;
411
412 while (tomoyo_invalid(c: *sp))
413 sp++;
414 while (*sp) {
415 if (!first)
416 *dp++ = ' ';
417 first = false;
418 while (tomoyo_valid(c: *sp))
419 *dp++ = *sp++;
420 while (tomoyo_invalid(c: *sp))
421 sp++;
422 }
423 *dp = '\0';
424}
425
426/**
427 * tomoyo_correct_word2 - Validate a string.
428 *
429 * @string: The string to check. Maybe non-'\0'-terminated.
430 * @len: Length of @string.
431 *
432 * Check whether the given string follows the naming rules.
433 * Returns true if @string follows the naming rules, false otherwise.
434 */
435static bool tomoyo_correct_word2(const char *string, size_t len)
436{
437 u8 recursion = 20;
438 const char *const start = string;
439 bool in_repetition = false;
440
441 if (!len)
442 goto out;
443 while (len--) {
444 unsigned char c = *string++;
445
446 if (c == '\\') {
447 if (!len--)
448 goto out;
449 c = *string++;
450 if (c >= '0' && c <= '3') {
451 unsigned char d;
452 unsigned char e;
453
454 if (!len-- || !len--)
455 goto out;
456 d = *string++;
457 e = *string++;
458 if (d < '0' || d > '7' || e < '0' || e > '7')
459 goto out;
460 c = tomoyo_make_byte(c1: c, c2: d, c3: e);
461 if (c <= ' ' || c >= 127)
462 continue;
463 goto out;
464 }
465 switch (c) {
466 case '\\': /* "\\" */
467 case '+': /* "\+" */
468 case '?': /* "\?" */
469 case 'x': /* "\x" */
470 case 'a': /* "\a" */
471 case '-': /* "\-" */
472 continue;
473 }
474 if (!recursion--)
475 goto out;
476 switch (c) {
477 case '*': /* "\*" */
478 case '@': /* "\@" */
479 case '$': /* "\$" */
480 case 'X': /* "\X" */
481 case 'A': /* "\A" */
482 continue;
483 case '{': /* "/\{" */
484 if (string - 3 < start || *(string - 3) != '/')
485 goto out;
486 in_repetition = true;
487 continue;
488 case '}': /* "\}/" */
489 if (*string != '/')
490 goto out;
491 if (!in_repetition)
492 goto out;
493 in_repetition = false;
494 continue;
495 }
496 goto out;
497 } else if (in_repetition && c == '/') {
498 goto out;
499 } else if (c <= ' ' || c >= 127) {
500 goto out;
501 }
502 }
503 if (in_repetition)
504 goto out;
505 return true;
506 out:
507 return false;
508}
509
510/**
511 * tomoyo_correct_word - Validate a string.
512 *
513 * @string: The string to check.
514 *
515 * Check whether the given string follows the naming rules.
516 * Returns true if @string follows the naming rules, false otherwise.
517 */
518bool tomoyo_correct_word(const char *string)
519{
520 return tomoyo_correct_word2(string, strlen(string));
521}
522
523/**
524 * tomoyo_correct_path2 - Check whether the given pathname follows the naming rules.
525 *
526 * @filename: The pathname to check.
527 * @len: Length of @filename.
528 *
529 * Returns true if @filename follows the naming rules, false otherwise.
530 */
531static bool tomoyo_correct_path2(const char *filename, const size_t len)
532{
533 const char *cp1 = memchr(p: filename, c: '/', size: len);
534 const char *cp2 = memchr(p: filename, c: '.', size: len);
535
536 return cp1 && (!cp2 || (cp1 < cp2)) && tomoyo_correct_word2(string: filename, len);
537}
538
539/**
540 * tomoyo_correct_path - Validate a pathname.
541 *
542 * @filename: The pathname to check.
543 *
544 * Check whether the given pathname follows the naming rules.
545 * Returns true if @filename follows the naming rules, false otherwise.
546 */
547bool tomoyo_correct_path(const char *filename)
548{
549 return tomoyo_correct_path2(filename, strlen(filename));
550}
551
552/**
553 * tomoyo_correct_domain - Check whether the given domainname follows the naming rules.
554 *
555 * @domainname: The domainname to check.
556 *
557 * Returns true if @domainname follows the naming rules, false otherwise.
558 */
559bool tomoyo_correct_domain(const unsigned char *domainname)
560{
561 if (!domainname || !tomoyo_domain_def(buffer: domainname))
562 return false;
563 domainname = strchr(domainname, ' ');
564 if (!domainname++)
565 return true;
566 while (1) {
567 const unsigned char *cp = strchr(domainname, ' ');
568
569 if (!cp)
570 break;
571 if (!tomoyo_correct_path2(filename: domainname, len: cp - domainname))
572 return false;
573 domainname = cp + 1;
574 }
575 return tomoyo_correct_path(filename: domainname);
576}
577
578/**
579 * tomoyo_domain_def - Check whether the given token can be a domainname.
580 *
581 * @buffer: The token to check.
582 *
583 * Returns true if @buffer possibly be a domainname, false otherwise.
584 */
585bool tomoyo_domain_def(const unsigned char *buffer)
586{
587 const unsigned char *cp;
588 int len;
589
590 if (*buffer != '<')
591 return false;
592 cp = strchr(buffer, ' ');
593 if (!cp)
594 len = strlen(buffer);
595 else
596 len = cp - buffer;
597 if (buffer[len - 1] != '>' ||
598 !tomoyo_correct_word2(string: buffer + 1, len: len - 2))
599 return false;
600 return true;
601}
602
603/**
604 * tomoyo_find_domain - Find a domain by the given name.
605 *
606 * @domainname: The domainname to find.
607 *
608 * Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise.
609 *
610 * Caller holds tomoyo_read_lock().
611 */
612struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname)
613{
614 struct tomoyo_domain_info *domain;
615 struct tomoyo_path_info name;
616
617 name.name = domainname;
618 tomoyo_fill_path_info(ptr: &name);
619 list_for_each_entry_rcu(domain, &tomoyo_domain_list, list,
620 srcu_read_lock_held(&tomoyo_ss)) {
621 if (!domain->is_deleted &&
622 !tomoyo_pathcmp(a: &name, b: domain->domainname))
623 return domain;
624 }
625 return NULL;
626}
627
628/**
629 * tomoyo_const_part_length - Evaluate the initial length without a pattern in a token.
630 *
631 * @filename: The string to evaluate.
632 *
633 * Returns the initial length without a pattern in @filename.
634 */
635static int tomoyo_const_part_length(const char *filename)
636{
637 char c;
638 int len = 0;
639
640 if (!filename)
641 return 0;
642 while ((c = *filename++) != '\0') {
643 if (c != '\\') {
644 len++;
645 continue;
646 }
647 c = *filename++;
648 switch (c) {
649 case '\\': /* "\\" */
650 len += 2;
651 continue;
652 case '0': /* "\ooo" */
653 case '1':
654 case '2':
655 case '3':
656 c = *filename++;
657 if (c < '0' || c > '7')
658 break;
659 c = *filename++;
660 if (c < '0' || c > '7')
661 break;
662 len += 4;
663 continue;
664 }
665 break;
666 }
667 return len;
668}
669
670/**
671 * tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members.
672 *
673 * @ptr: Pointer to "struct tomoyo_path_info" to fill in.
674 *
675 * The caller sets "struct tomoyo_path_info"->name.
676 */
677void tomoyo_fill_path_info(struct tomoyo_path_info *ptr)
678{
679 const char *name = ptr->name;
680 const int len = strlen(name);
681
682 ptr->const_len = tomoyo_const_part_length(filename: name);
683 ptr->is_dir = len && (name[len - 1] == '/');
684 ptr->is_patterned = (ptr->const_len < len);
685 ptr->hash = full_name_hash(NULL, name, len);
686}
687
688/**
689 * tomoyo_file_matches_pattern2 - Pattern matching without '/' character and "\-" pattern.
690 *
691 * @filename: The start of string to check.
692 * @filename_end: The end of string to check.
693 * @pattern: The start of pattern to compare.
694 * @pattern_end: The end of pattern to compare.
695 *
696 * Returns true if @filename matches @pattern, false otherwise.
697 */
698static bool tomoyo_file_matches_pattern2(const char *filename,
699 const char *filename_end,
700 const char *pattern,
701 const char *pattern_end)
702{
703 while (filename < filename_end && pattern < pattern_end) {
704 char c;
705 int i;
706 int j;
707
708 if (*pattern != '\\') {
709 if (*filename++ != *pattern++)
710 return false;
711 continue;
712 }
713 c = *filename;
714 pattern++;
715 switch (*pattern) {
716 case '?':
717 if (c == '/') {
718 return false;
719 } else if (c == '\\') {
720 if (filename[1] == '\\')
721 filename++;
722 else if (tomoyo_byte_range(str: filename + 1))
723 filename += 3;
724 else
725 return false;
726 }
727 break;
728 case '\\':
729 if (c != '\\')
730 return false;
731 if (*++filename != '\\')
732 return false;
733 break;
734 case '+':
735 if (!isdigit(c))
736 return false;
737 break;
738 case 'x':
739 if (!isxdigit(c))
740 return false;
741 break;
742 case 'a':
743 if (!tomoyo_alphabet_char(c))
744 return false;
745 break;
746 case '0':
747 case '1':
748 case '2':
749 case '3':
750 if (c == '\\' && tomoyo_byte_range(str: filename + 1)
751 && strncmp(filename + 1, pattern, 3) == 0) {
752 filename += 3;
753 pattern += 2;
754 break;
755 }
756 return false; /* Not matched. */
757 case '*':
758 case '@':
759 for (i = 0; i <= filename_end - filename; i++) {
760 if (tomoyo_file_matches_pattern2(
761 filename: filename + i, filename_end,
762 pattern: pattern + 1, pattern_end))
763 return true;
764 c = filename[i];
765 if (c == '.' && *pattern == '@')
766 break;
767 if (c != '\\')
768 continue;
769 if (filename[i + 1] == '\\')
770 i++;
771 else if (tomoyo_byte_range(str: filename + i + 1))
772 i += 3;
773 else
774 break; /* Bad pattern. */
775 }
776 return false; /* Not matched. */
777 default:
778 j = 0;
779 c = *pattern;
780 if (c == '$') {
781 while (isdigit(c: filename[j]))
782 j++;
783 } else if (c == 'X') {
784 while (isxdigit(filename[j]))
785 j++;
786 } else if (c == 'A') {
787 while (tomoyo_alphabet_char(c: filename[j]))
788 j++;
789 }
790 for (i = 1; i <= j; i++) {
791 if (tomoyo_file_matches_pattern2(
792 filename: filename + i, filename_end,
793 pattern: pattern + 1, pattern_end))
794 return true;
795 }
796 return false; /* Not matched or bad pattern. */
797 }
798 filename++;
799 pattern++;
800 }
801 while (*pattern == '\\' &&
802 (*(pattern + 1) == '*' || *(pattern + 1) == '@'))
803 pattern += 2;
804 return filename == filename_end && pattern == pattern_end;
805}
806
807/**
808 * tomoyo_file_matches_pattern - Pattern matching without '/' character.
809 *
810 * @filename: The start of string to check.
811 * @filename_end: The end of string to check.
812 * @pattern: The start of pattern to compare.
813 * @pattern_end: The end of pattern to compare.
814 *
815 * Returns true if @filename matches @pattern, false otherwise.
816 */
817static bool tomoyo_file_matches_pattern(const char *filename,
818 const char *filename_end,
819 const char *pattern,
820 const char *pattern_end)
821{
822 const char *pattern_start = pattern;
823 bool first = true;
824 bool result;
825
826 while (pattern < pattern_end - 1) {
827 /* Split at "\-" pattern. */
828 if (*pattern++ != '\\' || *pattern++ != '-')
829 continue;
830 result = tomoyo_file_matches_pattern2(filename,
831 filename_end,
832 pattern: pattern_start,
833 pattern_end: pattern - 2);
834 if (first)
835 result = !result;
836 if (result)
837 return false;
838 first = false;
839 pattern_start = pattern;
840 }
841 result = tomoyo_file_matches_pattern2(filename, filename_end,
842 pattern: pattern_start, pattern_end);
843 return first ? result : !result;
844}
845
846/**
847 * tomoyo_path_matches_pattern2 - Do pathname pattern matching.
848 *
849 * @f: The start of string to check.
850 * @p: The start of pattern to compare.
851 *
852 * Returns true if @f matches @p, false otherwise.
853 */
854static bool tomoyo_path_matches_pattern2(const char *f, const char *p)
855{
856 const char *f_delimiter;
857 const char *p_delimiter;
858
859 while (*f && *p) {
860 f_delimiter = strchr(f, '/');
861 if (!f_delimiter)
862 f_delimiter = f + strlen(f);
863 p_delimiter = strchr(p, '/');
864 if (!p_delimiter)
865 p_delimiter = p + strlen(p);
866 if (*p == '\\' && *(p + 1) == '{')
867 goto recursive;
868 if (!tomoyo_file_matches_pattern(filename: f, filename_end: f_delimiter, pattern: p,
869 pattern_end: p_delimiter))
870 return false;
871 f = f_delimiter;
872 if (*f)
873 f++;
874 p = p_delimiter;
875 if (*p)
876 p++;
877 }
878 /* Ignore trailing "\*" and "\@" in @pattern. */
879 while (*p == '\\' &&
880 (*(p + 1) == '*' || *(p + 1) == '@'))
881 p += 2;
882 return !*f && !*p;
883 recursive:
884 /*
885 * The "\{" pattern is permitted only after '/' character.
886 * This guarantees that below "*(p - 1)" is safe.
887 * Also, the "\}" pattern is permitted only before '/' character
888 * so that "\{" + "\}" pair will not break the "\-" operator.
889 */
890 if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' ||
891 *(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\')
892 return false; /* Bad pattern. */
893 do {
894 /* Compare current component with pattern. */
895 if (!tomoyo_file_matches_pattern(filename: f, filename_end: f_delimiter, pattern: p + 2,
896 pattern_end: p_delimiter - 2))
897 break;
898 /* Proceed to next component. */
899 f = f_delimiter;
900 if (!*f)
901 break;
902 f++;
903 /* Continue comparison. */
904 if (tomoyo_path_matches_pattern2(f, p: p_delimiter + 1))
905 return true;
906 f_delimiter = strchr(f, '/');
907 } while (f_delimiter);
908 return false; /* Not matched. */
909}
910
911/**
912 * tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern.
913 *
914 * @filename: The filename to check.
915 * @pattern: The pattern to compare.
916 *
917 * Returns true if matches, false otherwise.
918 *
919 * The following patterns are available.
920 * \\ \ itself.
921 * \ooo Octal representation of a byte.
922 * \* Zero or more repetitions of characters other than '/'.
923 * \@ Zero or more repetitions of characters other than '/' or '.'.
924 * \? 1 byte character other than '/'.
925 * \$ One or more repetitions of decimal digits.
926 * \+ 1 decimal digit.
927 * \X One or more repetitions of hexadecimal digits.
928 * \x 1 hexadecimal digit.
929 * \A One or more repetitions of alphabet characters.
930 * \a 1 alphabet character.
931 *
932 * \- Subtraction operator.
933 *
934 * /\{dir\}/ '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/
935 * /dir/dir/dir/ ).
936 */
937bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
938 const struct tomoyo_path_info *pattern)
939{
940 const char *f = filename->name;
941 const char *p = pattern->name;
942 const int len = pattern->const_len;
943
944 /* If @pattern doesn't contain pattern, I can use strcmp(). */
945 if (!pattern->is_patterned)
946 return !tomoyo_pathcmp(a: filename, b: pattern);
947 /* Don't compare directory and non-directory. */
948 if (filename->is_dir != pattern->is_dir)
949 return false;
950 /* Compare the initial length without patterns. */
951 if (strncmp(f, p, len))
952 return false;
953 f += len;
954 p += len;
955 return tomoyo_path_matches_pattern2(f, p);
956}
957
958/**
959 * tomoyo_get_exe - Get tomoyo_realpath() of current process.
960 *
961 * Returns the tomoyo_realpath() of current process on success, NULL otherwise.
962 *
963 * This function uses kzalloc(), so the caller must call kfree()
964 * if this function didn't return NULL.
965 */
966const char *tomoyo_get_exe(void)
967{
968 struct file *exe_file;
969 const char *cp;
970 struct mm_struct *mm = current->mm;
971
972 if (!mm)
973 return NULL;
974 exe_file = get_mm_exe_file(mm);
975 if (!exe_file)
976 return NULL;
977
978 cp = tomoyo_realpath_from_path(path: &exe_file->f_path);
979 fput(exe_file);
980 return cp;
981}
982
983/**
984 * tomoyo_get_mode - Get MAC mode.
985 *
986 * @ns: Pointer to "struct tomoyo_policy_namespace".
987 * @profile: Profile number.
988 * @index: Index number of functionality.
989 *
990 * Returns mode.
991 */
992int tomoyo_get_mode(const struct tomoyo_policy_namespace *ns, const u8 profile,
993 const u8 index)
994{
995 u8 mode;
996 struct tomoyo_profile *p;
997
998 if (!tomoyo_policy_loaded)
999 return TOMOYO_CONFIG_DISABLED;
1000 p = tomoyo_profile(ns, profile);
1001 mode = p->config[index];
1002 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
1003 mode = p->config[tomoyo_index2category[index]
1004 + TOMOYO_MAX_MAC_INDEX];
1005 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
1006 mode = p->default_config;
1007 return mode & 3;
1008}
1009
1010/**
1011 * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members.
1012 *
1013 * @r: Pointer to "struct tomoyo_request_info" to initialize.
1014 * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain().
1015 * @index: Index number of functionality.
1016 *
1017 * Returns mode.
1018 */
1019int tomoyo_init_request_info(struct tomoyo_request_info *r,
1020 struct tomoyo_domain_info *domain, const u8 index)
1021{
1022 u8 profile;
1023
1024 memset(r, 0, sizeof(*r));
1025 if (!domain)
1026 domain = tomoyo_domain();
1027 r->domain = domain;
1028 profile = domain->profile;
1029 r->profile = profile;
1030 r->type = index;
1031 r->mode = tomoyo_get_mode(ns: domain->ns, profile, index);
1032 return r->mode;
1033}
1034
1035/**
1036 * tomoyo_domain_quota_is_ok - Check for domain's quota.
1037 *
1038 * @r: Pointer to "struct tomoyo_request_info".
1039 *
1040 * Returns true if the domain is not exceeded quota, false otherwise.
1041 *
1042 * Caller holds tomoyo_read_lock().
1043 */
1044bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
1045{
1046 unsigned int count = 0;
1047 struct tomoyo_domain_info *domain = r->domain;
1048 struct tomoyo_acl_info *ptr;
1049
1050 if (r->mode != TOMOYO_CONFIG_LEARNING)
1051 return false;
1052 if (!domain)
1053 return true;
1054 if (READ_ONCE(domain->flags[TOMOYO_DIF_QUOTA_WARNED]))
1055 return false;
1056 list_for_each_entry_rcu(ptr, &domain->acl_info_list, list,
1057 srcu_read_lock_held(&tomoyo_ss)) {
1058 u16 perm;
1059
1060 if (ptr->is_deleted)
1061 continue;
1062 /*
1063 * Reading perm bitmap might race with tomoyo_merge_*() because
1064 * caller does not hold tomoyo_policy_lock mutex. But exceeding
1065 * max_learning_entry parameter by a few entries does not harm.
1066 */
1067 switch (ptr->type) {
1068 case TOMOYO_TYPE_PATH_ACL:
1069 perm = data_race(container_of(ptr, struct tomoyo_path_acl, head)->perm);
1070 break;
1071 case TOMOYO_TYPE_PATH2_ACL:
1072 perm = data_race(container_of(ptr, struct tomoyo_path2_acl, head)->perm);
1073 break;
1074 case TOMOYO_TYPE_PATH_NUMBER_ACL:
1075 perm = data_race(container_of(ptr, struct tomoyo_path_number_acl, head)
1076 ->perm);
1077 break;
1078 case TOMOYO_TYPE_MKDEV_ACL:
1079 perm = data_race(container_of(ptr, struct tomoyo_mkdev_acl, head)->perm);
1080 break;
1081 case TOMOYO_TYPE_INET_ACL:
1082 perm = data_race(container_of(ptr, struct tomoyo_inet_acl, head)->perm);
1083 break;
1084 case TOMOYO_TYPE_UNIX_ACL:
1085 perm = data_race(container_of(ptr, struct tomoyo_unix_acl, head)->perm);
1086 break;
1087 case TOMOYO_TYPE_MANUAL_TASK_ACL:
1088 perm = 0;
1089 break;
1090 default:
1091 perm = 1;
1092 }
1093 count += hweight16(perm);
1094 }
1095 if (count < tomoyo_profile(ns: domain->ns, profile: domain->profile)->
1096 pref[TOMOYO_PREF_MAX_LEARNING_ENTRY])
1097 return true;
1098 WRITE_ONCE(domain->flags[TOMOYO_DIF_QUOTA_WARNED], true);
1099 /* r->granted = false; */
1100 tomoyo_write_log(r, fmt: "%s", tomoyo_dif[TOMOYO_DIF_QUOTA_WARNED]);
1101#ifndef CONFIG_SECURITY_TOMOYO_INSECURE_BUILTIN_SETTING
1102 pr_warn("WARNING: Domain '%s' has too many ACLs to hold. Stopped learning mode.\n",
1103 domain->domainname->name);
1104#endif
1105 return false;
1106}
1107

source code of linux/security/tomoyo/util.c