Tetsuo Handa | c3ef150 | 2010-05-17 10:12:46 +0900 | [diff] [blame^] | 1 | /* |
| 2 | * security/tomoyo/util.c |
| 3 | * |
| 4 | * Utility functions for TOMOYO. |
| 5 | * |
| 6 | * Copyright (C) 2005-2010 NTT DATA CORPORATION |
| 7 | */ |
| 8 | |
| 9 | #include <linux/slab.h> |
| 10 | #include "common.h" |
| 11 | |
| 12 | /* Lock for protecting policy. */ |
| 13 | DEFINE_MUTEX(tomoyo_policy_lock); |
| 14 | |
| 15 | /* Has /sbin/init started? */ |
| 16 | bool tomoyo_policy_loaded; |
| 17 | |
| 18 | /** |
| 19 | * tomoyo_parse_ulong - Parse an "unsigned long" value. |
| 20 | * |
| 21 | * @result: Pointer to "unsigned long". |
| 22 | * @str: Pointer to string to parse. |
| 23 | * |
| 24 | * Returns value type on success, 0 otherwise. |
| 25 | * |
| 26 | * The @src is updated to point the first character after the value |
| 27 | * on success. |
| 28 | */ |
| 29 | u8 tomoyo_parse_ulong(unsigned long *result, char **str) |
| 30 | { |
| 31 | const char *cp = *str; |
| 32 | char *ep; |
| 33 | int base = 10; |
| 34 | if (*cp == '0') { |
| 35 | char c = *(cp + 1); |
| 36 | if (c == 'x' || c == 'X') { |
| 37 | base = 16; |
| 38 | cp += 2; |
| 39 | } else if (c >= '0' && c <= '7') { |
| 40 | base = 8; |
| 41 | cp++; |
| 42 | } |
| 43 | } |
| 44 | *result = simple_strtoul(cp, &ep, base); |
| 45 | if (cp == ep) |
| 46 | return 0; |
| 47 | *str = ep; |
| 48 | switch (base) { |
| 49 | case 16: |
| 50 | return TOMOYO_VALUE_TYPE_HEXADECIMAL; |
| 51 | case 8: |
| 52 | return TOMOYO_VALUE_TYPE_OCTAL; |
| 53 | default: |
| 54 | return TOMOYO_VALUE_TYPE_DECIMAL; |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | /** |
| 59 | * tomoyo_print_ulong - Print an "unsigned long" value. |
| 60 | * |
| 61 | * @buffer: Pointer to buffer. |
| 62 | * @buffer_len: Size of @buffer. |
| 63 | * @value: An "unsigned long" value. |
| 64 | * @type: Type of @value. |
| 65 | * |
| 66 | * Returns nothing. |
| 67 | */ |
| 68 | void tomoyo_print_ulong(char *buffer, const int buffer_len, |
| 69 | const unsigned long value, const u8 type) |
| 70 | { |
| 71 | if (type == TOMOYO_VALUE_TYPE_DECIMAL) |
| 72 | snprintf(buffer, buffer_len, "%lu", value); |
| 73 | else if (type == TOMOYO_VALUE_TYPE_OCTAL) |
| 74 | snprintf(buffer, buffer_len, "0%lo", value); |
| 75 | else if (type == TOMOYO_VALUE_TYPE_HEXADECIMAL) |
| 76 | snprintf(buffer, buffer_len, "0x%lX", value); |
| 77 | else |
| 78 | snprintf(buffer, buffer_len, "type(%u)", type); |
| 79 | } |
| 80 | |
| 81 | /** |
| 82 | * tomoyo_parse_name_union - Parse a tomoyo_name_union. |
| 83 | * |
| 84 | * @filename: Name or name group. |
| 85 | * @ptr: Pointer to "struct tomoyo_name_union". |
| 86 | * |
| 87 | * Returns true on success, false otherwise. |
| 88 | */ |
| 89 | bool tomoyo_parse_name_union(const char *filename, |
| 90 | struct tomoyo_name_union *ptr) |
| 91 | { |
| 92 | if (!tomoyo_is_correct_path(filename, 0, 0, 0)) |
| 93 | return false; |
| 94 | if (filename[0] == '@') { |
| 95 | ptr->group = tomoyo_get_path_group(filename + 1); |
| 96 | ptr->is_group = true; |
| 97 | return ptr->group != NULL; |
| 98 | } |
| 99 | ptr->filename = tomoyo_get_name(filename); |
| 100 | ptr->is_group = false; |
| 101 | return ptr->filename != NULL; |
| 102 | } |
| 103 | |
| 104 | /** |
| 105 | * tomoyo_parse_number_union - Parse a tomoyo_number_union. |
| 106 | * |
| 107 | * @data: Number or number range or number group. |
| 108 | * @ptr: Pointer to "struct tomoyo_number_union". |
| 109 | * |
| 110 | * Returns true on success, false otherwise. |
| 111 | */ |
| 112 | bool tomoyo_parse_number_union(char *data, struct tomoyo_number_union *num) |
| 113 | { |
| 114 | u8 type; |
| 115 | unsigned long v; |
| 116 | memset(num, 0, sizeof(*num)); |
| 117 | if (data[0] == '@') { |
| 118 | if (!tomoyo_is_correct_path(data, 0, 0, 0)) |
| 119 | return false; |
| 120 | num->group = tomoyo_get_number_group(data + 1); |
| 121 | num->is_group = true; |
| 122 | return num->group != NULL; |
| 123 | } |
| 124 | type = tomoyo_parse_ulong(&v, &data); |
| 125 | if (!type) |
| 126 | return false; |
| 127 | num->values[0] = v; |
| 128 | num->min_type = type; |
| 129 | if (!*data) { |
| 130 | num->values[1] = v; |
| 131 | num->max_type = type; |
| 132 | return true; |
| 133 | } |
| 134 | if (*data++ != '-') |
| 135 | return false; |
| 136 | type = tomoyo_parse_ulong(&v, &data); |
| 137 | if (!type || *data) |
| 138 | return false; |
| 139 | num->values[1] = v; |
| 140 | num->max_type = type; |
| 141 | return true; |
| 142 | } |
| 143 | |
| 144 | /** |
| 145 | * tomoyo_is_byte_range - Check whether the string is a \ooo style octal value. |
| 146 | * |
| 147 | * @str: Pointer to the string. |
| 148 | * |
| 149 | * Returns true if @str is a \ooo style octal value, false otherwise. |
| 150 | * |
| 151 | * TOMOYO uses \ooo style representation for 0x01 - 0x20 and 0x7F - 0xFF. |
| 152 | * This function verifies that \ooo is in valid range. |
| 153 | */ |
| 154 | static inline bool tomoyo_is_byte_range(const char *str) |
| 155 | { |
| 156 | return *str >= '0' && *str++ <= '3' && |
| 157 | *str >= '0' && *str++ <= '7' && |
| 158 | *str >= '0' && *str <= '7'; |
| 159 | } |
| 160 | |
| 161 | /** |
| 162 | * tomoyo_is_alphabet_char - Check whether the character is an alphabet. |
| 163 | * |
| 164 | * @c: The character to check. |
| 165 | * |
| 166 | * Returns true if @c is an alphabet character, false otherwise. |
| 167 | */ |
| 168 | static inline bool tomoyo_is_alphabet_char(const char c) |
| 169 | { |
| 170 | return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z'); |
| 171 | } |
| 172 | |
| 173 | /** |
| 174 | * tomoyo_make_byte - Make byte value from three octal characters. |
| 175 | * |
| 176 | * @c1: The first character. |
| 177 | * @c2: The second character. |
| 178 | * @c3: The third character. |
| 179 | * |
| 180 | * Returns byte value. |
| 181 | */ |
| 182 | static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3) |
| 183 | { |
| 184 | return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0'); |
| 185 | } |
| 186 | |
| 187 | /** |
| 188 | * tomoyo_str_starts - Check whether the given string starts with the given keyword. |
| 189 | * |
| 190 | * @src: Pointer to pointer to the string. |
| 191 | * @find: Pointer to the keyword. |
| 192 | * |
| 193 | * Returns true if @src starts with @find, false otherwise. |
| 194 | * |
| 195 | * The @src is updated to point the first character after the @find |
| 196 | * if @src starts with @find. |
| 197 | */ |
| 198 | bool tomoyo_str_starts(char **src, const char *find) |
| 199 | { |
| 200 | const int len = strlen(find); |
| 201 | char *tmp = *src; |
| 202 | |
| 203 | if (strncmp(tmp, find, len)) |
| 204 | return false; |
| 205 | tmp += len; |
| 206 | *src = tmp; |
| 207 | return true; |
| 208 | } |
| 209 | |
| 210 | /** |
| 211 | * tomoyo_normalize_line - Format string. |
| 212 | * |
| 213 | * @buffer: The line to normalize. |
| 214 | * |
| 215 | * Leading and trailing whitespaces are removed. |
| 216 | * Multiple whitespaces are packed into single space. |
| 217 | * |
| 218 | * Returns nothing. |
| 219 | */ |
| 220 | void tomoyo_normalize_line(unsigned char *buffer) |
| 221 | { |
| 222 | unsigned char *sp = buffer; |
| 223 | unsigned char *dp = buffer; |
| 224 | bool first = true; |
| 225 | |
| 226 | while (tomoyo_is_invalid(*sp)) |
| 227 | sp++; |
| 228 | while (*sp) { |
| 229 | if (!first) |
| 230 | *dp++ = ' '; |
| 231 | first = false; |
| 232 | while (tomoyo_is_valid(*sp)) |
| 233 | *dp++ = *sp++; |
| 234 | while (tomoyo_is_invalid(*sp)) |
| 235 | sp++; |
| 236 | } |
| 237 | *dp = '\0'; |
| 238 | } |
| 239 | |
| 240 | /** |
| 241 | * tomoyo_tokenize - Tokenize string. |
| 242 | * |
| 243 | * @buffer: The line to tokenize. |
| 244 | * @w: Pointer to "char *". |
| 245 | * @size: Sizeof @w . |
| 246 | * |
| 247 | * Returns true on success, false otherwise. |
| 248 | */ |
| 249 | bool tomoyo_tokenize(char *buffer, char *w[], size_t size) |
| 250 | { |
| 251 | int count = size / sizeof(char *); |
| 252 | int i; |
| 253 | for (i = 0; i < count; i++) |
| 254 | w[i] = ""; |
| 255 | for (i = 0; i < count; i++) { |
| 256 | char *cp = strchr(buffer, ' '); |
| 257 | if (cp) |
| 258 | *cp = '\0'; |
| 259 | w[i] = buffer; |
| 260 | if (!cp) |
| 261 | break; |
| 262 | buffer = cp + 1; |
| 263 | } |
| 264 | return i < count || !*buffer; |
| 265 | } |
| 266 | |
| 267 | /** |
| 268 | * tomoyo_is_correct_path - Validate a pathname. |
| 269 | * |
| 270 | * @filename: The pathname to check. |
| 271 | * @start_type: Should the pathname start with '/'? |
| 272 | * 1 = must / -1 = must not / 0 = don't care |
| 273 | * @pattern_type: Can the pathname contain a wildcard? |
| 274 | * 1 = must / -1 = must not / 0 = don't care |
| 275 | * @end_type: Should the pathname end with '/'? |
| 276 | * 1 = must / -1 = must not / 0 = don't care |
| 277 | * |
| 278 | * Check whether the given filename follows the naming rules. |
| 279 | * Returns true if @filename follows the naming rules, false otherwise. |
| 280 | */ |
| 281 | bool tomoyo_is_correct_path(const char *filename, const s8 start_type, |
| 282 | const s8 pattern_type, const s8 end_type) |
| 283 | { |
| 284 | const char *const start = filename; |
| 285 | bool in_repetition = false; |
| 286 | bool contains_pattern = false; |
| 287 | unsigned char c; |
| 288 | unsigned char d; |
| 289 | unsigned char e; |
| 290 | |
| 291 | if (!filename) |
| 292 | goto out; |
| 293 | c = *filename; |
| 294 | if (start_type == 1) { /* Must start with '/' */ |
| 295 | if (c != '/') |
| 296 | goto out; |
| 297 | } else if (start_type == -1) { /* Must not start with '/' */ |
| 298 | if (c == '/') |
| 299 | goto out; |
| 300 | } |
| 301 | if (c) |
| 302 | c = *(filename + strlen(filename) - 1); |
| 303 | if (end_type == 1) { /* Must end with '/' */ |
| 304 | if (c != '/') |
| 305 | goto out; |
| 306 | } else if (end_type == -1) { /* Must not end with '/' */ |
| 307 | if (c == '/') |
| 308 | goto out; |
| 309 | } |
| 310 | while (1) { |
| 311 | c = *filename++; |
| 312 | if (!c) |
| 313 | break; |
| 314 | if (c == '\\') { |
| 315 | c = *filename++; |
| 316 | switch (c) { |
| 317 | case '\\': /* "\\" */ |
| 318 | continue; |
| 319 | case '$': /* "\$" */ |
| 320 | case '+': /* "\+" */ |
| 321 | case '?': /* "\?" */ |
| 322 | case '*': /* "\*" */ |
| 323 | case '@': /* "\@" */ |
| 324 | case 'x': /* "\x" */ |
| 325 | case 'X': /* "\X" */ |
| 326 | case 'a': /* "\a" */ |
| 327 | case 'A': /* "\A" */ |
| 328 | case '-': /* "\-" */ |
| 329 | if (pattern_type == -1) |
| 330 | break; /* Must not contain pattern */ |
| 331 | contains_pattern = true; |
| 332 | continue; |
| 333 | case '{': /* "/\{" */ |
| 334 | if (filename - 3 < start || |
| 335 | *(filename - 3) != '/') |
| 336 | break; |
| 337 | if (pattern_type == -1) |
| 338 | break; /* Must not contain pattern */ |
| 339 | contains_pattern = true; |
| 340 | in_repetition = true; |
| 341 | continue; |
| 342 | case '}': /* "\}/" */ |
| 343 | if (*filename != '/') |
| 344 | break; |
| 345 | if (!in_repetition) |
| 346 | break; |
| 347 | in_repetition = false; |
| 348 | continue; |
| 349 | case '0': /* "\ooo" */ |
| 350 | case '1': |
| 351 | case '2': |
| 352 | case '3': |
| 353 | d = *filename++; |
| 354 | if (d < '0' || d > '7') |
| 355 | break; |
| 356 | e = *filename++; |
| 357 | if (e < '0' || e > '7') |
| 358 | break; |
| 359 | c = tomoyo_make_byte(c, d, e); |
| 360 | if (tomoyo_is_invalid(c)) |
| 361 | continue; /* pattern is not \000 */ |
| 362 | } |
| 363 | goto out; |
| 364 | } else if (in_repetition && c == '/') { |
| 365 | goto out; |
| 366 | } else if (tomoyo_is_invalid(c)) { |
| 367 | goto out; |
| 368 | } |
| 369 | } |
| 370 | if (pattern_type == 1) { /* Must contain pattern */ |
| 371 | if (!contains_pattern) |
| 372 | goto out; |
| 373 | } |
| 374 | if (in_repetition) |
| 375 | goto out; |
| 376 | return true; |
| 377 | out: |
| 378 | return false; |
| 379 | } |
| 380 | |
| 381 | /** |
| 382 | * tomoyo_is_correct_domain - Check whether the given domainname follows the naming rules. |
| 383 | * |
| 384 | * @domainname: The domainname to check. |
| 385 | * |
| 386 | * Returns true if @domainname follows the naming rules, false otherwise. |
| 387 | */ |
| 388 | bool tomoyo_is_correct_domain(const unsigned char *domainname) |
| 389 | { |
| 390 | unsigned char c; |
| 391 | unsigned char d; |
| 392 | unsigned char e; |
| 393 | |
| 394 | if (!domainname || strncmp(domainname, TOMOYO_ROOT_NAME, |
| 395 | TOMOYO_ROOT_NAME_LEN)) |
| 396 | goto out; |
| 397 | domainname += TOMOYO_ROOT_NAME_LEN; |
| 398 | if (!*domainname) |
| 399 | return true; |
| 400 | do { |
| 401 | if (*domainname++ != ' ') |
| 402 | goto out; |
| 403 | if (*domainname++ != '/') |
| 404 | goto out; |
| 405 | while ((c = *domainname) != '\0' && c != ' ') { |
| 406 | domainname++; |
| 407 | if (c == '\\') { |
| 408 | c = *domainname++; |
| 409 | switch ((c)) { |
| 410 | case '\\': /* "\\" */ |
| 411 | continue; |
| 412 | case '0': /* "\ooo" */ |
| 413 | case '1': |
| 414 | case '2': |
| 415 | case '3': |
| 416 | d = *domainname++; |
| 417 | if (d < '0' || d > '7') |
| 418 | break; |
| 419 | e = *domainname++; |
| 420 | if (e < '0' || e > '7') |
| 421 | break; |
| 422 | c = tomoyo_make_byte(c, d, e); |
| 423 | if (tomoyo_is_invalid(c)) |
| 424 | /* pattern is not \000 */ |
| 425 | continue; |
| 426 | } |
| 427 | goto out; |
| 428 | } else if (tomoyo_is_invalid(c)) { |
| 429 | goto out; |
| 430 | } |
| 431 | } |
| 432 | } while (*domainname); |
| 433 | return true; |
| 434 | out: |
| 435 | return false; |
| 436 | } |
| 437 | |
| 438 | /** |
| 439 | * tomoyo_is_domain_def - Check whether the given token can be a domainname. |
| 440 | * |
| 441 | * @buffer: The token to check. |
| 442 | * |
| 443 | * Returns true if @buffer possibly be a domainname, false otherwise. |
| 444 | */ |
| 445 | bool tomoyo_is_domain_def(const unsigned char *buffer) |
| 446 | { |
| 447 | return !strncmp(buffer, TOMOYO_ROOT_NAME, TOMOYO_ROOT_NAME_LEN); |
| 448 | } |
| 449 | |
| 450 | /** |
| 451 | * tomoyo_find_domain - Find a domain by the given name. |
| 452 | * |
| 453 | * @domainname: The domainname to find. |
| 454 | * |
| 455 | * Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise. |
| 456 | * |
| 457 | * Caller holds tomoyo_read_lock(). |
| 458 | */ |
| 459 | struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname) |
| 460 | { |
| 461 | struct tomoyo_domain_info *domain; |
| 462 | struct tomoyo_path_info name; |
| 463 | |
| 464 | name.name = domainname; |
| 465 | tomoyo_fill_path_info(&name); |
| 466 | list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) { |
| 467 | if (!domain->is_deleted && |
| 468 | !tomoyo_pathcmp(&name, domain->domainname)) |
| 469 | return domain; |
| 470 | } |
| 471 | return NULL; |
| 472 | } |
| 473 | |
| 474 | /** |
| 475 | * tomoyo_const_part_length - Evaluate the initial length without a pattern in a token. |
| 476 | * |
| 477 | * @filename: The string to evaluate. |
| 478 | * |
| 479 | * Returns the initial length without a pattern in @filename. |
| 480 | */ |
| 481 | static int tomoyo_const_part_length(const char *filename) |
| 482 | { |
| 483 | char c; |
| 484 | int len = 0; |
| 485 | |
| 486 | if (!filename) |
| 487 | return 0; |
| 488 | while ((c = *filename++) != '\0') { |
| 489 | if (c != '\\') { |
| 490 | len++; |
| 491 | continue; |
| 492 | } |
| 493 | c = *filename++; |
| 494 | switch (c) { |
| 495 | case '\\': /* "\\" */ |
| 496 | len += 2; |
| 497 | continue; |
| 498 | case '0': /* "\ooo" */ |
| 499 | case '1': |
| 500 | case '2': |
| 501 | case '3': |
| 502 | c = *filename++; |
| 503 | if (c < '0' || c > '7') |
| 504 | break; |
| 505 | c = *filename++; |
| 506 | if (c < '0' || c > '7') |
| 507 | break; |
| 508 | len += 4; |
| 509 | continue; |
| 510 | } |
| 511 | break; |
| 512 | } |
| 513 | return len; |
| 514 | } |
| 515 | |
| 516 | /** |
| 517 | * tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members. |
| 518 | * |
| 519 | * @ptr: Pointer to "struct tomoyo_path_info" to fill in. |
| 520 | * |
| 521 | * The caller sets "struct tomoyo_path_info"->name. |
| 522 | */ |
| 523 | void tomoyo_fill_path_info(struct tomoyo_path_info *ptr) |
| 524 | { |
| 525 | const char *name = ptr->name; |
| 526 | const int len = strlen(name); |
| 527 | |
| 528 | ptr->const_len = tomoyo_const_part_length(name); |
| 529 | ptr->is_dir = len && (name[len - 1] == '/'); |
| 530 | ptr->is_patterned = (ptr->const_len < len); |
| 531 | ptr->hash = full_name_hash(name, len); |
| 532 | } |
| 533 | |
| 534 | /** |
| 535 | * tomoyo_file_matches_pattern2 - Pattern matching without '/' character and "\-" pattern. |
| 536 | * |
| 537 | * @filename: The start of string to check. |
| 538 | * @filename_end: The end of string to check. |
| 539 | * @pattern: The start of pattern to compare. |
| 540 | * @pattern_end: The end of pattern to compare. |
| 541 | * |
| 542 | * Returns true if @filename matches @pattern, false otherwise. |
| 543 | */ |
| 544 | static bool tomoyo_file_matches_pattern2(const char *filename, |
| 545 | const char *filename_end, |
| 546 | const char *pattern, |
| 547 | const char *pattern_end) |
| 548 | { |
| 549 | while (filename < filename_end && pattern < pattern_end) { |
| 550 | char c; |
| 551 | if (*pattern != '\\') { |
| 552 | if (*filename++ != *pattern++) |
| 553 | return false; |
| 554 | continue; |
| 555 | } |
| 556 | c = *filename; |
| 557 | pattern++; |
| 558 | switch (*pattern) { |
| 559 | int i; |
| 560 | int j; |
| 561 | case '?': |
| 562 | if (c == '/') { |
| 563 | return false; |
| 564 | } else if (c == '\\') { |
| 565 | if (filename[1] == '\\') |
| 566 | filename++; |
| 567 | else if (tomoyo_is_byte_range(filename + 1)) |
| 568 | filename += 3; |
| 569 | else |
| 570 | return false; |
| 571 | } |
| 572 | break; |
| 573 | case '\\': |
| 574 | if (c != '\\') |
| 575 | return false; |
| 576 | if (*++filename != '\\') |
| 577 | return false; |
| 578 | break; |
| 579 | case '+': |
| 580 | if (!isdigit(c)) |
| 581 | return false; |
| 582 | break; |
| 583 | case 'x': |
| 584 | if (!isxdigit(c)) |
| 585 | return false; |
| 586 | break; |
| 587 | case 'a': |
| 588 | if (!tomoyo_is_alphabet_char(c)) |
| 589 | return false; |
| 590 | break; |
| 591 | case '0': |
| 592 | case '1': |
| 593 | case '2': |
| 594 | case '3': |
| 595 | if (c == '\\' && tomoyo_is_byte_range(filename + 1) |
| 596 | && strncmp(filename + 1, pattern, 3) == 0) { |
| 597 | filename += 3; |
| 598 | pattern += 2; |
| 599 | break; |
| 600 | } |
| 601 | return false; /* Not matched. */ |
| 602 | case '*': |
| 603 | case '@': |
| 604 | for (i = 0; i <= filename_end - filename; i++) { |
| 605 | if (tomoyo_file_matches_pattern2( |
| 606 | filename + i, filename_end, |
| 607 | pattern + 1, pattern_end)) |
| 608 | return true; |
| 609 | c = filename[i]; |
| 610 | if (c == '.' && *pattern == '@') |
| 611 | break; |
| 612 | if (c != '\\') |
| 613 | continue; |
| 614 | if (filename[i + 1] == '\\') |
| 615 | i++; |
| 616 | else if (tomoyo_is_byte_range(filename + i + 1)) |
| 617 | i += 3; |
| 618 | else |
| 619 | break; /* Bad pattern. */ |
| 620 | } |
| 621 | return false; /* Not matched. */ |
| 622 | default: |
| 623 | j = 0; |
| 624 | c = *pattern; |
| 625 | if (c == '$') { |
| 626 | while (isdigit(filename[j])) |
| 627 | j++; |
| 628 | } else if (c == 'X') { |
| 629 | while (isxdigit(filename[j])) |
| 630 | j++; |
| 631 | } else if (c == 'A') { |
| 632 | while (tomoyo_is_alphabet_char(filename[j])) |
| 633 | j++; |
| 634 | } |
| 635 | for (i = 1; i <= j; i++) { |
| 636 | if (tomoyo_file_matches_pattern2( |
| 637 | filename + i, filename_end, |
| 638 | pattern + 1, pattern_end)) |
| 639 | return true; |
| 640 | } |
| 641 | return false; /* Not matched or bad pattern. */ |
| 642 | } |
| 643 | filename++; |
| 644 | pattern++; |
| 645 | } |
| 646 | while (*pattern == '\\' && |
| 647 | (*(pattern + 1) == '*' || *(pattern + 1) == '@')) |
| 648 | pattern += 2; |
| 649 | return filename == filename_end && pattern == pattern_end; |
| 650 | } |
| 651 | |
| 652 | /** |
| 653 | * tomoyo_file_matches_pattern - Pattern matching without '/' character. |
| 654 | * |
| 655 | * @filename: The start of string to check. |
| 656 | * @filename_end: The end of string to check. |
| 657 | * @pattern: The start of pattern to compare. |
| 658 | * @pattern_end: The end of pattern to compare. |
| 659 | * |
| 660 | * Returns true if @filename matches @pattern, false otherwise. |
| 661 | */ |
| 662 | static bool tomoyo_file_matches_pattern(const char *filename, |
| 663 | const char *filename_end, |
| 664 | const char *pattern, |
| 665 | const char *pattern_end) |
| 666 | { |
| 667 | const char *pattern_start = pattern; |
| 668 | bool first = true; |
| 669 | bool result; |
| 670 | |
| 671 | while (pattern < pattern_end - 1) { |
| 672 | /* Split at "\-" pattern. */ |
| 673 | if (*pattern++ != '\\' || *pattern++ != '-') |
| 674 | continue; |
| 675 | result = tomoyo_file_matches_pattern2(filename, |
| 676 | filename_end, |
| 677 | pattern_start, |
| 678 | pattern - 2); |
| 679 | if (first) |
| 680 | result = !result; |
| 681 | if (result) |
| 682 | return false; |
| 683 | first = false; |
| 684 | pattern_start = pattern; |
| 685 | } |
| 686 | result = tomoyo_file_matches_pattern2(filename, filename_end, |
| 687 | pattern_start, pattern_end); |
| 688 | return first ? result : !result; |
| 689 | } |
| 690 | |
| 691 | /** |
| 692 | * tomoyo_path_matches_pattern2 - Do pathname pattern matching. |
| 693 | * |
| 694 | * @f: The start of string to check. |
| 695 | * @p: The start of pattern to compare. |
| 696 | * |
| 697 | * Returns true if @f matches @p, false otherwise. |
| 698 | */ |
| 699 | static bool tomoyo_path_matches_pattern2(const char *f, const char *p) |
| 700 | { |
| 701 | const char *f_delimiter; |
| 702 | const char *p_delimiter; |
| 703 | |
| 704 | while (*f && *p) { |
| 705 | f_delimiter = strchr(f, '/'); |
| 706 | if (!f_delimiter) |
| 707 | f_delimiter = f + strlen(f); |
| 708 | p_delimiter = strchr(p, '/'); |
| 709 | if (!p_delimiter) |
| 710 | p_delimiter = p + strlen(p); |
| 711 | if (*p == '\\' && *(p + 1) == '{') |
| 712 | goto recursive; |
| 713 | if (!tomoyo_file_matches_pattern(f, f_delimiter, p, |
| 714 | p_delimiter)) |
| 715 | return false; |
| 716 | f = f_delimiter; |
| 717 | if (*f) |
| 718 | f++; |
| 719 | p = p_delimiter; |
| 720 | if (*p) |
| 721 | p++; |
| 722 | } |
| 723 | /* Ignore trailing "\*" and "\@" in @pattern. */ |
| 724 | while (*p == '\\' && |
| 725 | (*(p + 1) == '*' || *(p + 1) == '@')) |
| 726 | p += 2; |
| 727 | return !*f && !*p; |
| 728 | recursive: |
| 729 | /* |
| 730 | * The "\{" pattern is permitted only after '/' character. |
| 731 | * This guarantees that below "*(p - 1)" is safe. |
| 732 | * Also, the "\}" pattern is permitted only before '/' character |
| 733 | * so that "\{" + "\}" pair will not break the "\-" operator. |
| 734 | */ |
| 735 | if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' || |
| 736 | *(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\') |
| 737 | return false; /* Bad pattern. */ |
| 738 | do { |
| 739 | /* Compare current component with pattern. */ |
| 740 | if (!tomoyo_file_matches_pattern(f, f_delimiter, p + 2, |
| 741 | p_delimiter - 2)) |
| 742 | break; |
| 743 | /* Proceed to next component. */ |
| 744 | f = f_delimiter; |
| 745 | if (!*f) |
| 746 | break; |
| 747 | f++; |
| 748 | /* Continue comparison. */ |
| 749 | if (tomoyo_path_matches_pattern2(f, p_delimiter + 1)) |
| 750 | return true; |
| 751 | f_delimiter = strchr(f, '/'); |
| 752 | } while (f_delimiter); |
| 753 | return false; /* Not matched. */ |
| 754 | } |
| 755 | |
| 756 | /** |
| 757 | * tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern. |
| 758 | * |
| 759 | * @filename: The filename to check. |
| 760 | * @pattern: The pattern to compare. |
| 761 | * |
| 762 | * Returns true if matches, false otherwise. |
| 763 | * |
| 764 | * The following patterns are available. |
| 765 | * \\ \ itself. |
| 766 | * \ooo Octal representation of a byte. |
| 767 | * \* Zero or more repetitions of characters other than '/'. |
| 768 | * \@ Zero or more repetitions of characters other than '/' or '.'. |
| 769 | * \? 1 byte character other than '/'. |
| 770 | * \$ One or more repetitions of decimal digits. |
| 771 | * \+ 1 decimal digit. |
| 772 | * \X One or more repetitions of hexadecimal digits. |
| 773 | * \x 1 hexadecimal digit. |
| 774 | * \A One or more repetitions of alphabet characters. |
| 775 | * \a 1 alphabet character. |
| 776 | * |
| 777 | * \- Subtraction operator. |
| 778 | * |
| 779 | * /\{dir\}/ '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/ |
| 780 | * /dir/dir/dir/ ). |
| 781 | */ |
| 782 | bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename, |
| 783 | const struct tomoyo_path_info *pattern) |
| 784 | { |
| 785 | const char *f = filename->name; |
| 786 | const char *p = pattern->name; |
| 787 | const int len = pattern->const_len; |
| 788 | |
| 789 | /* If @pattern doesn't contain pattern, I can use strcmp(). */ |
| 790 | if (!pattern->is_patterned) |
| 791 | return !tomoyo_pathcmp(filename, pattern); |
| 792 | /* Don't compare directory and non-directory. */ |
| 793 | if (filename->is_dir != pattern->is_dir) |
| 794 | return false; |
| 795 | /* Compare the initial length without patterns. */ |
| 796 | if (strncmp(f, p, len)) |
| 797 | return false; |
| 798 | f += len; |
| 799 | p += len; |
| 800 | return tomoyo_path_matches_pattern2(f, p); |
| 801 | } |
| 802 | |
| 803 | /** |
| 804 | * tomoyo_get_exe - Get tomoyo_realpath() of current process. |
| 805 | * |
| 806 | * Returns the tomoyo_realpath() of current process on success, NULL otherwise. |
| 807 | * |
| 808 | * This function uses kzalloc(), so the caller must call kfree() |
| 809 | * if this function didn't return NULL. |
| 810 | */ |
| 811 | const char *tomoyo_get_exe(void) |
| 812 | { |
| 813 | struct mm_struct *mm = current->mm; |
| 814 | struct vm_area_struct *vma; |
| 815 | const char *cp = NULL; |
| 816 | |
| 817 | if (!mm) |
| 818 | return NULL; |
| 819 | down_read(&mm->mmap_sem); |
| 820 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
| 821 | if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file) { |
| 822 | cp = tomoyo_realpath_from_path(&vma->vm_file->f_path); |
| 823 | break; |
| 824 | } |
| 825 | } |
| 826 | up_read(&mm->mmap_sem); |
| 827 | return cp; |
| 828 | } |
| 829 | |
| 830 | /** |
| 831 | * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members. |
| 832 | * |
| 833 | * @r: Pointer to "struct tomoyo_request_info" to initialize. |
| 834 | * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain(). |
| 835 | * |
| 836 | * Returns mode. |
| 837 | */ |
| 838 | int tomoyo_init_request_info(struct tomoyo_request_info *r, |
| 839 | struct tomoyo_domain_info *domain) |
| 840 | { |
| 841 | memset(r, 0, sizeof(*r)); |
| 842 | if (!domain) |
| 843 | domain = tomoyo_domain(); |
| 844 | r->domain = domain; |
| 845 | r->mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE); |
| 846 | return r->mode; |
| 847 | } |
| 848 | |
| 849 | /** |
| 850 | * tomoyo_warn_log - Print warning or error message on console. |
| 851 | * |
| 852 | * @r: Pointer to "struct tomoyo_request_info". |
| 853 | * @fmt: The printf()'s format string, followed by parameters. |
| 854 | */ |
| 855 | void tomoyo_warn_log(struct tomoyo_request_info *r, const char *fmt, ...) |
| 856 | { |
| 857 | int len = PAGE_SIZE; |
| 858 | va_list args; |
| 859 | char *buffer; |
| 860 | if (!tomoyo_verbose_mode(r->domain)) |
| 861 | return; |
| 862 | while (1) { |
| 863 | int len2; |
| 864 | buffer = kmalloc(len, GFP_NOFS); |
| 865 | if (!buffer) |
| 866 | return; |
| 867 | va_start(args, fmt); |
| 868 | len2 = vsnprintf(buffer, len - 1, fmt, args); |
| 869 | va_end(args); |
| 870 | if (len2 <= len - 1) { |
| 871 | buffer[len2] = '\0'; |
| 872 | break; |
| 873 | } |
| 874 | len = len2 + 1; |
| 875 | kfree(buffer); |
| 876 | } |
| 877 | printk(KERN_WARNING "TOMOYO-%s: Access %s denied for %s\n", |
| 878 | r->mode == TOMOYO_CONFIG_ENFORCING ? "ERROR" : "WARNING", |
| 879 | buffer, tomoyo_get_last_name(r->domain)); |
| 880 | kfree(buffer); |
| 881 | } |
| 882 | |
| 883 | /** |
| 884 | * tomoyo_domain_quota_is_ok - Check for domain's quota. |
| 885 | * |
| 886 | * @r: Pointer to "struct tomoyo_request_info". |
| 887 | * |
| 888 | * Returns true if the domain is not exceeded quota, false otherwise. |
| 889 | * |
| 890 | * Caller holds tomoyo_read_lock(). |
| 891 | */ |
| 892 | bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r) |
| 893 | { |
| 894 | unsigned int count = 0; |
| 895 | struct tomoyo_domain_info *domain = r->domain; |
| 896 | struct tomoyo_acl_info *ptr; |
| 897 | |
| 898 | if (r->mode != TOMOYO_CONFIG_LEARNING) |
| 899 | return false; |
| 900 | if (!domain) |
| 901 | return true; |
| 902 | list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) { |
| 903 | switch (ptr->type) { |
| 904 | u16 perm; |
| 905 | u8 i; |
| 906 | case TOMOYO_TYPE_PATH_ACL: |
| 907 | perm = container_of(ptr, struct tomoyo_path_acl, head) |
| 908 | ->perm; |
| 909 | for (i = 0; i < TOMOYO_MAX_PATH_OPERATION; i++) |
| 910 | if (perm & (1 << i)) |
| 911 | count++; |
| 912 | if (perm & (1 << TOMOYO_TYPE_READ_WRITE)) |
| 913 | count -= 2; |
| 914 | break; |
| 915 | case TOMOYO_TYPE_PATH2_ACL: |
| 916 | perm = container_of(ptr, struct tomoyo_path2_acl, head) |
| 917 | ->perm; |
| 918 | for (i = 0; i < TOMOYO_MAX_PATH2_OPERATION; i++) |
| 919 | if (perm & (1 << i)) |
| 920 | count++; |
| 921 | break; |
| 922 | case TOMOYO_TYPE_PATH_NUMBER_ACL: |
| 923 | perm = container_of(ptr, struct tomoyo_path_number_acl, |
| 924 | head)->perm; |
| 925 | for (i = 0; i < TOMOYO_MAX_PATH_NUMBER_OPERATION; i++) |
| 926 | if (perm & (1 << i)) |
| 927 | count++; |
| 928 | break; |
| 929 | case TOMOYO_TYPE_PATH_NUMBER3_ACL: |
| 930 | perm = container_of(ptr, struct tomoyo_path_number3_acl, |
| 931 | head)->perm; |
| 932 | for (i = 0; i < TOMOYO_MAX_PATH_NUMBER3_OPERATION; i++) |
| 933 | if (perm & (1 << i)) |
| 934 | count++; |
| 935 | break; |
| 936 | case TOMOYO_TYPE_MOUNT_ACL: |
| 937 | if (!container_of(ptr, struct tomoyo_mount_acl, head)-> |
| 938 | is_deleted) |
| 939 | count++; |
| 940 | } |
| 941 | } |
| 942 | if (count < tomoyo_check_flags(domain, TOMOYO_MAX_ACCEPT_ENTRY)) |
| 943 | return true; |
| 944 | if (!domain->quota_warned) { |
| 945 | domain->quota_warned = true; |
| 946 | printk(KERN_WARNING "TOMOYO-WARNING: " |
| 947 | "Domain '%s' has so many ACLs to hold. " |
| 948 | "Stopped learning mode.\n", domain->domainname->name); |
| 949 | } |
| 950 | return false; |
| 951 | } |