security/tomoyo/util.c

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

DEFINITIONS
