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TOMOYO Linux Cross Reference
Linux/security/tomoyo/util.c

Version: ~ [ linux-5.2 ] ~ [ linux-5.1.16 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.57 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.132 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.184 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.184 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.69 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
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  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  */
 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  */
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  */
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  */
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  */
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 == '') {
203                 char c = *(cp + 1);
204                 if (c == 'x' || c == 'X') {
205                         base = 16;
206                         cp += 2;
207                 } else if (c >= '' && 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  */
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  */
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  */
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  */
324 static inline bool tomoyo_byte_range(const char *str)
325 {
326         return *str >= '' && *str++ <= '3' &&
327                 *str >= '' && *str++ <= '7' &&
328                 *str >= '' && *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  */
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  */
352 static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
353 {
354         return ((c1 - '') << 6) + ((c2 - '') << 3) + (c3 - '');
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  */
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  */
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  */
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  */
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  */
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 '':   /* "\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 < '' || d > '7' || e < '' || 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  */
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  */
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  */
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  */
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  */
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  */
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 '':   /* "\ooo" */
637                 case '1':
638                 case '2':
639                 case '3':
640                         c = *filename++;
641                         if (c < '' || c > '7')
642                                 break;
643                         c = *filename++;
644                         if (c < '' || 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  */
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  */
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 '':
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  */
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  */
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  */
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  */
949 const char *tomoyo_get_exe(void)
950 {
951         struct file *exe_file;
952         const char *cp;
953         struct mm_struct *mm = current->mm;
954 
955         if (!mm)
956                 return NULL;
957         exe_file = get_mm_exe_file(mm);
958         if (!exe_file)
959                 return NULL;
960 
961         cp = tomoyo_realpath_from_path(&exe_file->f_path);
962         fput(exe_file);
963         return cp;
964 }
965 
966 /**
967  * tomoyo_get_mode - Get MAC mode.
968  *
969  * @ns:      Pointer to "struct tomoyo_policy_namespace".
970  * @profile: Profile number.
971  * @index:   Index number of functionality.
972  *
973  * Returns mode.
974  */
975 int tomoyo_get_mode(const struct tomoyo_policy_namespace *ns, const u8 profile,
976                     const u8 index)
977 {
978         u8 mode;
979         struct tomoyo_profile *p;
980 
981         if (!tomoyo_policy_loaded)
982                 return TOMOYO_CONFIG_DISABLED;
983         p = tomoyo_profile(ns, profile);
984         mode = p->config[index];
985         if (mode == TOMOYO_CONFIG_USE_DEFAULT)
986                 mode = p->config[tomoyo_index2category[index]
987                                  + TOMOYO_MAX_MAC_INDEX];
988         if (mode == TOMOYO_CONFIG_USE_DEFAULT)
989                 mode = p->default_config;
990         return mode & 3;
991 }
992 
993 /**
994  * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members.
995  *
996  * @r:      Pointer to "struct tomoyo_request_info" to initialize.
997  * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain().
998  * @index:  Index number of functionality.
999  *
1000  * Returns mode.
1001  */
1002 int tomoyo_init_request_info(struct tomoyo_request_info *r,
1003                              struct tomoyo_domain_info *domain, const u8 index)
1004 {
1005         u8 profile;
1006         memset(r, 0, sizeof(*r));
1007         if (!domain)
1008                 domain = tomoyo_domain();
1009         r->domain = domain;
1010         profile = domain->profile;
1011         r->profile = profile;
1012         r->type = index;
1013         r->mode = tomoyo_get_mode(domain->ns, profile, index);
1014         return r->mode;
1015 }
1016 
1017 /**
1018  * tomoyo_domain_quota_is_ok - Check for domain's quota.
1019  *
1020  * @r: Pointer to "struct tomoyo_request_info".
1021  *
1022  * Returns true if the domain is not exceeded quota, false otherwise.
1023  *
1024  * Caller holds tomoyo_read_lock().
1025  */
1026 bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
1027 {
1028         unsigned int count = 0;
1029         struct tomoyo_domain_info *domain = r->domain;
1030         struct tomoyo_acl_info *ptr;
1031 
1032         if (r->mode != TOMOYO_CONFIG_LEARNING)
1033                 return false;
1034         if (!domain)
1035                 return true;
1036         list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
1037                 u16 perm;
1038                 u8 i;
1039                 if (ptr->is_deleted)
1040                         continue;
1041                 switch (ptr->type) {
1042                 case TOMOYO_TYPE_PATH_ACL:
1043                         perm = container_of(ptr, struct tomoyo_path_acl, head)
1044                                 ->perm;
1045                         break;
1046                 case TOMOYO_TYPE_PATH2_ACL:
1047                         perm = container_of(ptr, struct tomoyo_path2_acl, head)
1048                                 ->perm;
1049                         break;
1050                 case TOMOYO_TYPE_PATH_NUMBER_ACL:
1051                         perm = container_of(ptr, struct tomoyo_path_number_acl,
1052                                             head)->perm;
1053                         break;
1054                 case TOMOYO_TYPE_MKDEV_ACL:
1055                         perm = container_of(ptr, struct tomoyo_mkdev_acl,
1056                                             head)->perm;
1057                         break;
1058                 case TOMOYO_TYPE_INET_ACL:
1059                         perm = container_of(ptr, struct tomoyo_inet_acl,
1060                                             head)->perm;
1061                         break;
1062                 case TOMOYO_TYPE_UNIX_ACL:
1063                         perm = container_of(ptr, struct tomoyo_unix_acl,
1064                                             head)->perm;
1065                         break;
1066                 case TOMOYO_TYPE_MANUAL_TASK_ACL:
1067                         perm = 0;
1068                         break;
1069                 default:
1070                         perm = 1;
1071                 }
1072                 for (i = 0; i < 16; i++)
1073                         if (perm & (1 << i))
1074                                 count++;
1075         }
1076         if (count < tomoyo_profile(domain->ns, domain->profile)->
1077             pref[TOMOYO_PREF_MAX_LEARNING_ENTRY])
1078                 return true;
1079         if (!domain->flags[TOMOYO_DIF_QUOTA_WARNED]) {
1080                 domain->flags[TOMOYO_DIF_QUOTA_WARNED] = true;
1081                 /* r->granted = false; */
1082                 tomoyo_write_log(r, "%s", tomoyo_dif[TOMOYO_DIF_QUOTA_WARNED]);
1083                 printk(KERN_WARNING "WARNING: "
1084                        "Domain '%s' has too many ACLs to hold. "
1085                        "Stopped learning mode.\n", domain->domainname->name);
1086         }
1087         return false;
1088 }
1089 

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