linux/security/tomoyo/util.c
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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. */
  11DEFINE_MUTEX(tomoyo_policy_lock);
  12
  13/* Has /sbin/init started? */
  14bool tomoyo_policy_loaded;
  15
  16/*
  17 * Mapping table from "enum tomoyo_mac_index" to
  18 * "enum tomoyo_mac_category_index".
  19 */
  20const 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 */
  90void 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 */
 131bool 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 */
 149char *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 */
 168const 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 */
 197u8 tomoyo_parse_ulong(unsigned long *result, char **str)
 198{
 199        const char *cp = *str;
 200        char *ep;
 201        int base = 10;
 202        if (*cp == '0') {
 203                char c = *(cp + 1);
 204                if (c == 'x' || c == 'X') {
 205                        base = 16;
 206                        cp += 2;
 207                } else if (c >= '0' && c <= '7') {
 208                        base = 8;
 209                        cp++;
 210                }
 211        }
 212        *result = simple_strtoul(cp, &ep, base);
 213        if (cp == ep)
 214                return TOMOYO_VALUE_TYPE_INVALID;
 215        *str = ep;
 216        switch (base) {
 217        case 16:
 218                return TOMOYO_VALUE_TYPE_HEXADECIMAL;
 219        case 8:
 220                return TOMOYO_VALUE_TYPE_OCTAL;
 221        default:
 222                return TOMOYO_VALUE_TYPE_DECIMAL;
 223        }
 224}
 225
 226/**
 227 * tomoyo_print_ulong - Print an "unsigned long" value.
 228 *
 229 * @buffer:     Pointer to buffer.
 230 * @buffer_len: Size of @buffer.
 231 * @value:      An "unsigned long" value.
 232 * @type:       Type of @value.
 233 *
 234 * Returns nothing.
 235 */
 236void 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 */
 257bool 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 */
 281bool 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 */
 324static inline bool tomoyo_byte_range(const char *str)
 325{
 326        return *str >= '0' && *str++ <= '3' &&
 327                *str >= '0' && *str++ <= '7' &&
 328                *str >= '0' && *str <= '7';
 329}
 330
 331/**
 332 * tomoyo_alphabet_char - Check whether the character is an alphabet.
 333 *
 334 * @c: The character to check.
 335 *
 336 * Returns true if @c is an alphabet character, false otherwise.
 337 */
 338static 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 */
 352static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
 353{
 354        return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
 355}
 356
 357/**
 358 * tomoyo_valid - Check whether the character is a valid char.
 359 *
 360 * @c: The character to check.
 361 *
 362 * Returns true if @c is a valid character, false otherwise.
 363 */
 364static 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 */
 376static 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 */
 392bool 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 */
 414void 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 */
 443static bool tomoyo_correct_word2(const char *string, size_t len)
 444{
 445        const char *const start = string;
 446        bool in_repetition = false;
 447        unsigned char c;
 448        unsigned char d;
 449        unsigned char e;
 450        if (!len)
 451                goto out;
 452        while (len--) {
 453                c = *string++;
 454                if (c == '\\') {
 455                        if (!len--)
 456                                goto out;
 457                        c = *string++;
 458                        switch (c) {
 459                        case '\\':  /* "\\" */
 460                                continue;
 461                        case '$':   /* "\$" */
 462                        case '+':   /* "\+" */
 463                        case '?':   /* "\?" */
 464                        case '*':   /* "\*" */
 465                        case '@':   /* "\@" */
 466                        case 'x':   /* "\x" */
 467                        case 'X':   /* "\X" */
 468                        case 'a':   /* "\a" */
 469                        case 'A':   /* "\A" */
 470                        case '-':   /* "\-" */
 471                                continue;
 472                        case '{':   /* "/\{" */
 473                                if (string - 3 < start || *(string - 3) != '/')
 474                                        break;
 475                                in_repetition = true;
 476                                continue;
 477                        case '}':   /* "\}/" */
 478                                if (*string != '/')
 479                                        break;
 480                                if (!in_repetition)
 481                                        break;
 482                                in_repetition = false;
 483                                continue;
 484                        case '0':   /* "\ooo" */
 485                        case '1':
 486                        case '2':
 487                        case '3':
 488                                if (!len-- || !len--)
 489                                        break;
 490                                d = *string++;
 491                                e = *string++;
 492                                if (d < '0' || d > '7' || e < '0' || e > '7')
 493                                        break;
 494                                c = tomoyo_make_byte(c, d, e);
 495                                if (c <= ' ' || c >= 127)
 496                                        continue;
 497                        }
 498                        goto out;
 499                } else if (in_repetition && c == '/') {
 500                        goto out;
 501                } else if (c <= ' ' || c >= 127) {
 502                        goto out;
 503                }
 504        }
 505        if (in_repetition)
 506                goto out;
 507        return true;
 508 out:
 509        return false;
 510}
 511
 512/**
 513 * tomoyo_correct_word - Validate a string.
 514 *
 515 * @string: The string to check.
 516 *
 517 * Check whether the given string follows the naming rules.
 518 * Returns true if @string follows the naming rules, false otherwise.
 519 */
 520bool 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 */
 533bool 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 */
 545bool 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 */
 571bool 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 */
 597struct 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 */
 619static int tomoyo_const_part_length(const char *filename)
 620{
 621        char c;
 622        int len = 0;
 623
 624        if (!filename)
 625                return 0;
 626        while ((c = *filename++) != '\0') {
 627                if (c != '\\') {
 628                        len++;
 629                        continue;
 630                }
 631                c = *filename++;
 632                switch (c) {
 633                case '\\':  /* "\\" */
 634                        len += 2;
 635                        continue;
 636                case '0':   /* "\ooo" */
 637                case '1':
 638                case '2':
 639                case '3':
 640                        c = *filename++;
 641                        if (c < '0' || c > '7')
 642                                break;
 643                        c = *filename++;
 644                        if (c < '0' || c > '7')
 645                                break;
 646                        len += 4;
 647                        continue;
 648                }
 649                break;
 650        }
 651        return len;
 652}
 653
 654/**
 655 * tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members.
 656 *
 657 * @ptr: Pointer to "struct tomoyo_path_info" to fill in.
 658 *
 659 * The caller sets "struct tomoyo_path_info"->name.
 660 */
 661void 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 */
 682static bool tomoyo_file_matches_pattern2(const char *filename,
 683                                         const char *filename_end,
 684                                         const char *pattern,
 685                                         const char *pattern_end)
 686{
 687        while (filename < filename_end && pattern < pattern_end) {
 688                char c;
 689                if (*pattern != '\\') {
 690                        if (*filename++ != *pattern++)
 691                                return false;
 692                        continue;
 693                }
 694                c = *filename;
 695                pattern++;
 696                switch (*pattern) {
 697                        int i;
 698                        int j;
 699                case '?':
 700                        if (c == '/') {
 701                                return false;
 702                        } else if (c == '\\') {
 703                                if (filename[1] == '\\')
 704                                        filename++;
 705                                else if (tomoyo_byte_range(filename + 1))
 706                                        filename += 3;
 707                                else
 708                                        return false;
 709                        }
 710                        break;
 711                case '\\':
 712                        if (c != '\\')
 713                                return false;
 714                        if (*++filename != '\\')
 715                                return false;
 716                        break;
 717                case '+':
 718                        if (!isdigit(c))
 719                                return false;
 720                        break;
 721                case 'x':
 722                        if (!isxdigit(c))
 723                                return false;
 724                        break;
 725                case 'a':
 726                        if (!tomoyo_alphabet_char(c))
 727                                return false;
 728                        break;
 729                case '0':
 730                case '1':
 731                case '2':
 732                case '3':
 733                        if (c == '\\' && tomoyo_byte_range(filename + 1)
 734                            && strncmp(filename + 1, pattern, 3) == 0) {
 735                                filename += 3;
 736                                pattern += 2;
 737                                break;
 738                        }
 739                        return false; /* Not matched. */
 740                case '*':
 741                case '@':
 742                        for (i = 0; i <= filename_end - filename; i++) {
 743                                if (tomoyo_file_matches_pattern2(
 744                                                    filename + i, filename_end,
 745                                                    pattern + 1, pattern_end))
 746                                        return true;
 747                                c = filename[i];
 748                                if (c == '.' && *pattern == '@')
 749                                        break;
 750                                if (c != '\\')
 751                                        continue;
 752                                if (filename[i + 1] == '\\')
 753                                        i++;
 754                                else if (tomoyo_byte_range(filename + i + 1))
 755                                        i += 3;
 756                                else
 757                                        break; /* Bad pattern. */
 758                        }
 759                        return false; /* Not matched. */
 760                default:
 761                        j = 0;
 762                        c = *pattern;
 763                        if (c == '$') {
 764                                while (isdigit(filename[j]))
 765                                        j++;
 766                        } else if (c == 'X') {
 767                                while (isxdigit(filename[j]))
 768                                        j++;
 769                        } else if (c == 'A') {
 770                                while (tomoyo_alphabet_char(filename[j]))
 771                                        j++;
 772                        }
 773                        for (i = 1; i <= j; i++) {
 774                                if (tomoyo_file_matches_pattern2(
 775                                                    filename + i, filename_end,
 776                                                    pattern + 1, pattern_end))
 777                                        return true;
 778                        }
 779                        return false; /* Not matched or bad pattern. */
 780                }
 781                filename++;
 782                pattern++;
 783        }
 784        while (*pattern == '\\' &&
 785               (*(pattern + 1) == '*' || *(pattern + 1) == '@'))
 786                pattern += 2;
 787        return filename == filename_end && pattern == pattern_end;
 788}
 789
 790/**
 791 * tomoyo_file_matches_pattern - Pattern matching without '/' character.
 792 *
 793 * @filename:     The start of string to check.
 794 * @filename_end: The end of string to check.
 795 * @pattern:      The start of pattern to compare.
 796 * @pattern_end:  The end of pattern to compare.
 797 *
 798 * Returns true if @filename matches @pattern, false otherwise.
 799 */
 800static 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 */
 837static 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 */
 920bool 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 */
 949const char *tomoyo_get_exe(void)
 950{
 951        struct mm_struct *mm = current->mm;
 952        const char *cp = NULL;
 953
 954        if (!mm)
 955                return NULL;
 956        down_read(&mm->mmap_sem);
 957        if (mm->exe_file)
 958                cp = tomoyo_realpath_from_path(&mm->exe_file->f_path);
 959        up_read(&mm->mmap_sem);
 960        return cp;
 961}
 962
 963/**
 964 * tomoyo_get_mode - Get MAC mode.
 965 *
 966 * @ns:      Pointer to "struct tomoyo_policy_namespace".
 967 * @profile: Profile number.
 968 * @index:   Index number of functionality.
 969 *
 970 * Returns mode.
 971 */
 972int tomoyo_get_mode(const struct tomoyo_policy_namespace *ns, const u8 profile,
 973                    const u8 index)
 974{
 975        u8 mode;
 976        struct tomoyo_profile *p;
 977
 978        if (!tomoyo_policy_loaded)
 979                return TOMOYO_CONFIG_DISABLED;
 980        p = tomoyo_profile(ns, profile);
 981        mode = p->config[index];
 982        if (mode == TOMOYO_CONFIG_USE_DEFAULT)
 983                mode = p->config[tomoyo_index2category[index]
 984                                 + TOMOYO_MAX_MAC_INDEX];
 985        if (mode == TOMOYO_CONFIG_USE_DEFAULT)
 986                mode = p->default_config;
 987        return mode & 3;
 988}
 989
 990/**
 991 * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members.
 992 *
 993 * @r:      Pointer to "struct tomoyo_request_info" to initialize.
 994 * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain().
 995 * @index:  Index number of functionality.
 996 *
 997 * Returns mode.
 998 */
 999int tomoyo_init_request_info(struct tomoyo_request_info *r,
1000                             struct tomoyo_domain_info *domain, const u8 index)
1001{
1002        u8 profile;
1003        memset(r, 0, sizeof(*r));
1004        if (!domain)
1005                domain = tomoyo_domain();
1006        r->domain = domain;
1007        profile = domain->profile;
1008        r->profile = profile;
1009        r->type = index;
1010        r->mode = tomoyo_get_mode(domain->ns, profile, index);
1011        return r->mode;
1012}
1013
1014/**
1015 * tomoyo_domain_quota_is_ok - Check for domain's quota.
1016 *
1017 * @r: Pointer to "struct tomoyo_request_info".
1018 *
1019 * Returns true if the domain is not exceeded quota, false otherwise.
1020 *
1021 * Caller holds tomoyo_read_lock().
1022 */
1023bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
1024{
1025        unsigned int count = 0;
1026        struct tomoyo_domain_info *domain = r->domain;
1027        struct tomoyo_acl_info *ptr;
1028
1029        if (r->mode != TOMOYO_CONFIG_LEARNING)
1030                return false;
1031        if (!domain)
1032                return true;
1033        list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
1034                u16 perm;
1035                u8 i;
1036                if (ptr->is_deleted)
1037                        continue;
1038                switch (ptr->type) {
1039                case TOMOYO_TYPE_PATH_ACL:
1040                        perm = container_of(ptr, struct tomoyo_path_acl, head)
1041                                ->perm;
1042                        break;
1043                case TOMOYO_TYPE_PATH2_ACL:
1044                        perm = container_of(ptr, struct tomoyo_path2_acl, head)
1045                                ->perm;
1046                        break;
1047                case TOMOYO_TYPE_PATH_NUMBER_ACL:
1048                        perm = container_of(ptr, struct tomoyo_path_number_acl,
1049                                            head)->perm;
1050                        break;
1051                case TOMOYO_TYPE_MKDEV_ACL:
1052                        perm = container_of(ptr, struct tomoyo_mkdev_acl,
1053                                            head)->perm;
1054                        break;
1055                case TOMOYO_TYPE_INET_ACL:
1056                        perm = container_of(ptr, struct tomoyo_inet_acl,
1057                                            head)->perm;
1058                        break;
1059                case TOMOYO_TYPE_UNIX_ACL:
1060                        perm = container_of(ptr, struct tomoyo_unix_acl,
1061                                            head)->perm;
1062                        break;
1063                case TOMOYO_TYPE_MANUAL_TASK_ACL:
1064                        perm = 0;
1065                        break;
1066                default:
1067                        perm = 1;
1068                }
1069                for (i = 0; i < 16; i++)
1070                        if (perm & (1 << i))
1071                                count++;
1072        }
1073        if (count < tomoyo_profile(domain->ns, domain->profile)->
1074            pref[TOMOYO_PREF_MAX_LEARNING_ENTRY])
1075                return true;
1076        if (!domain->flags[TOMOYO_DIF_QUOTA_WARNED]) {
1077                domain->flags[TOMOYO_DIF_QUOTA_WARNED] = true;
1078                /* r->granted = false; */
1079                tomoyo_write_log(r, "%s", tomoyo_dif[TOMOYO_DIF_QUOTA_WARNED]);
1080                printk(KERN_WARNING "WARNING: "
1081                       "Domain '%s' has too many ACLs to hold. "
1082                       "Stopped learning mode.\n", domain->domainname->name);
1083        }
1084        return false;
1085}
1086
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