linux/security/tomoyo/condition.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * security/tomoyo/condition.c
   4 *
   5 * Copyright (C) 2005-2011  NTT DATA CORPORATION
   6 */
   7
   8#include "common.h"
   9#include <linux/slab.h>
  10
  11/* List of "struct tomoyo_condition". */
  12LIST_HEAD(tomoyo_condition_list);
  13
  14/**
  15 * tomoyo_argv - Check argv[] in "struct linux_binbrm".
  16 *
  17 * @index:   Index number of @arg_ptr.
  18 * @arg_ptr: Contents of argv[@index].
  19 * @argc:    Length of @argv.
  20 * @argv:    Pointer to "struct tomoyo_argv".
  21 * @checked: Set to true if @argv[@index] was found.
  22 *
  23 * Returns true on success, false otherwise.
  24 */
  25static bool tomoyo_argv(const unsigned int index, const char *arg_ptr,
  26                        const int argc, const struct tomoyo_argv *argv,
  27                        u8 *checked)
  28{
  29        int i;
  30        struct tomoyo_path_info arg;
  31
  32        arg.name = arg_ptr;
  33        for (i = 0; i < argc; argv++, checked++, i++) {
  34                bool result;
  35
  36                if (index != argv->index)
  37                        continue;
  38                *checked = 1;
  39                tomoyo_fill_path_info(&arg);
  40                result = tomoyo_path_matches_pattern(&arg, argv->value);
  41                if (argv->is_not)
  42                        result = !result;
  43                if (!result)
  44                        return false;
  45        }
  46        return true;
  47}
  48
  49/**
  50 * tomoyo_envp - Check envp[] in "struct linux_binbrm".
  51 *
  52 * @env_name:  The name of environment variable.
  53 * @env_value: The value of environment variable.
  54 * @envc:      Length of @envp.
  55 * @envp:      Pointer to "struct tomoyo_envp".
  56 * @checked:   Set to true if @envp[@env_name] was found.
  57 *
  58 * Returns true on success, false otherwise.
  59 */
  60static bool tomoyo_envp(const char *env_name, const char *env_value,
  61                        const int envc, const struct tomoyo_envp *envp,
  62                        u8 *checked)
  63{
  64        int i;
  65        struct tomoyo_path_info name;
  66        struct tomoyo_path_info value;
  67
  68        name.name = env_name;
  69        tomoyo_fill_path_info(&name);
  70        value.name = env_value;
  71        tomoyo_fill_path_info(&value);
  72        for (i = 0; i < envc; envp++, checked++, i++) {
  73                bool result;
  74
  75                if (!tomoyo_path_matches_pattern(&name, envp->name))
  76                        continue;
  77                *checked = 1;
  78                if (envp->value) {
  79                        result = tomoyo_path_matches_pattern(&value,
  80                                                             envp->value);
  81                        if (envp->is_not)
  82                                result = !result;
  83                } else {
  84                        result = true;
  85                        if (!envp->is_not)
  86                                result = !result;
  87                }
  88                if (!result)
  89                        return false;
  90        }
  91        return true;
  92}
  93
  94/**
  95 * tomoyo_scan_bprm - Scan "struct linux_binprm".
  96 *
  97 * @ee:   Pointer to "struct tomoyo_execve".
  98 * @argc: Length of @argc.
  99 * @argv: Pointer to "struct tomoyo_argv".
 100 * @envc: Length of @envp.
 101 * @envp: Poiner to "struct tomoyo_envp".
 102 *
 103 * Returns true on success, false otherwise.
 104 */
 105static bool tomoyo_scan_bprm(struct tomoyo_execve *ee,
 106                             const u16 argc, const struct tomoyo_argv *argv,
 107                             const u16 envc, const struct tomoyo_envp *envp)
 108{
 109        struct linux_binprm *bprm = ee->bprm;
 110        struct tomoyo_page_dump *dump = &ee->dump;
 111        char *arg_ptr = ee->tmp;
 112        int arg_len = 0;
 113        unsigned long pos = bprm->p;
 114        int offset = pos % PAGE_SIZE;
 115        int argv_count = bprm->argc;
 116        int envp_count = bprm->envc;
 117        bool result = true;
 118        u8 local_checked[32];
 119        u8 *checked;
 120
 121        if (argc + envc <= sizeof(local_checked)) {
 122                checked = local_checked;
 123                memset(local_checked, 0, sizeof(local_checked));
 124        } else {
 125                checked = kzalloc(argc + envc, GFP_NOFS);
 126                if (!checked)
 127                        return false;
 128        }
 129        while (argv_count || envp_count) {
 130                if (!tomoyo_dump_page(bprm, pos, dump)) {
 131                        result = false;
 132                        goto out;
 133                }
 134                pos += PAGE_SIZE - offset;
 135                while (offset < PAGE_SIZE) {
 136                        /* Read. */
 137                        const char *kaddr = dump->data;
 138                        const unsigned char c = kaddr[offset++];
 139
 140                        if (c && arg_len < TOMOYO_EXEC_TMPSIZE - 10) {
 141                                if (c == '\\') {
 142                                        arg_ptr[arg_len++] = '\\';
 143                                        arg_ptr[arg_len++] = '\\';
 144                                } else if (c > ' ' && c < 127) {
 145                                        arg_ptr[arg_len++] = c;
 146                                } else {
 147                                        arg_ptr[arg_len++] = '\\';
 148                                        arg_ptr[arg_len++] = (c >> 6) + '0';
 149                                        arg_ptr[arg_len++] =
 150                                                ((c >> 3) & 7) + '0';
 151                                        arg_ptr[arg_len++] = (c & 7) + '0';
 152                                }
 153                        } else {
 154                                arg_ptr[arg_len] = '\0';
 155                        }
 156                        if (c)
 157                                continue;
 158                        /* Check. */
 159                        if (argv_count) {
 160                                if (!tomoyo_argv(bprm->argc - argv_count,
 161                                                 arg_ptr, argc, argv,
 162                                                 checked)) {
 163                                        result = false;
 164                                        break;
 165                                }
 166                                argv_count--;
 167                        } else if (envp_count) {
 168                                char *cp = strchr(arg_ptr, '=');
 169
 170                                if (cp) {
 171                                        *cp = '\0';
 172                                        if (!tomoyo_envp(arg_ptr, cp + 1,
 173                                                         envc, envp,
 174                                                         checked + argc)) {
 175                                                result = false;
 176                                                break;
 177                                        }
 178                                }
 179                                envp_count--;
 180                        } else {
 181                                break;
 182                        }
 183                        arg_len = 0;
 184                }
 185                offset = 0;
 186                if (!result)
 187                        break;
 188        }
 189out:
 190        if (result) {
 191                int i;
 192
 193                /* Check not-yet-checked entries. */
 194                for (i = 0; i < argc; i++) {
 195                        if (checked[i])
 196                                continue;
 197                        /*
 198                         * Return true only if all unchecked indexes in
 199                         * bprm->argv[] are not matched.
 200                         */
 201                        if (argv[i].is_not)
 202                                continue;
 203                        result = false;
 204                        break;
 205                }
 206                for (i = 0; i < envc; envp++, i++) {
 207                        if (checked[argc + i])
 208                                continue;
 209                        /*
 210                         * Return true only if all unchecked environ variables
 211                         * in bprm->envp[] are either undefined or not matched.
 212                         */
 213                        if ((!envp->value && !envp->is_not) ||
 214                            (envp->value && envp->is_not))
 215                                continue;
 216                        result = false;
 217                        break;
 218                }
 219        }
 220        if (checked != local_checked)
 221                kfree(checked);
 222        return result;
 223}
 224
 225/**
 226 * tomoyo_scan_exec_realpath - Check "exec.realpath" parameter of "struct tomoyo_condition".
 227 *
 228 * @file:  Pointer to "struct file".
 229 * @ptr:   Pointer to "struct tomoyo_name_union".
 230 * @match: True if "exec.realpath=", false if "exec.realpath!=".
 231 *
 232 * Returns true on success, false otherwise.
 233 */
 234static bool tomoyo_scan_exec_realpath(struct file *file,
 235                                      const struct tomoyo_name_union *ptr,
 236                                      const bool match)
 237{
 238        bool result;
 239        struct tomoyo_path_info exe;
 240
 241        if (!file)
 242                return false;
 243        exe.name = tomoyo_realpath_from_path(&file->f_path);
 244        if (!exe.name)
 245                return false;
 246        tomoyo_fill_path_info(&exe);
 247        result = tomoyo_compare_name_union(&exe, ptr);
 248        kfree(exe.name);
 249        return result == match;
 250}
 251
 252/**
 253 * tomoyo_get_dqword - tomoyo_get_name() for a quoted string.
 254 *
 255 * @start: String to save.
 256 *
 257 * Returns pointer to "struct tomoyo_path_info" on success, NULL otherwise.
 258 */
 259static const struct tomoyo_path_info *tomoyo_get_dqword(char *start)
 260{
 261        char *cp = start + strlen(start) - 1;
 262
 263        if (cp == start || *start++ != '"' || *cp != '"')
 264                return NULL;
 265        *cp = '\0';
 266        if (*start && !tomoyo_correct_word(start))
 267                return NULL;
 268        return tomoyo_get_name(start);
 269}
 270
 271/**
 272 * tomoyo_parse_name_union_quoted - Parse a quoted word.
 273 *
 274 * @param: Pointer to "struct tomoyo_acl_param".
 275 * @ptr:   Pointer to "struct tomoyo_name_union".
 276 *
 277 * Returns true on success, false otherwise.
 278 */
 279static bool tomoyo_parse_name_union_quoted(struct tomoyo_acl_param *param,
 280                                           struct tomoyo_name_union *ptr)
 281{
 282        char *filename = param->data;
 283
 284        if (*filename == '@')
 285                return tomoyo_parse_name_union(param, ptr);
 286        ptr->filename = tomoyo_get_dqword(filename);
 287        return ptr->filename != NULL;
 288}
 289
 290/**
 291 * tomoyo_parse_argv - Parse an argv[] condition part.
 292 *
 293 * @left:  Lefthand value.
 294 * @right: Righthand value.
 295 * @argv:  Pointer to "struct tomoyo_argv".
 296 *
 297 * Returns true on success, false otherwise.
 298 */
 299static bool tomoyo_parse_argv(char *left, char *right,
 300                              struct tomoyo_argv *argv)
 301{
 302        if (tomoyo_parse_ulong(&argv->index, &left) !=
 303            TOMOYO_VALUE_TYPE_DECIMAL || *left++ != ']' || *left)
 304                return false;
 305        argv->value = tomoyo_get_dqword(right);
 306        return argv->value != NULL;
 307}
 308
 309/**
 310 * tomoyo_parse_envp - Parse an envp[] condition part.
 311 *
 312 * @left:  Lefthand value.
 313 * @right: Righthand value.
 314 * @envp:  Pointer to "struct tomoyo_envp".
 315 *
 316 * Returns true on success, false otherwise.
 317 */
 318static bool tomoyo_parse_envp(char *left, char *right,
 319                              struct tomoyo_envp *envp)
 320{
 321        const struct tomoyo_path_info *name;
 322        const struct tomoyo_path_info *value;
 323        char *cp = left + strlen(left) - 1;
 324
 325        if (*cp-- != ']' || *cp != '"')
 326                goto out;
 327        *cp = '\0';
 328        if (!tomoyo_correct_word(left))
 329                goto out;
 330        name = tomoyo_get_name(left);
 331        if (!name)
 332                goto out;
 333        if (!strcmp(right, "NULL")) {
 334                value = NULL;
 335        } else {
 336                value = tomoyo_get_dqword(right);
 337                if (!value) {
 338                        tomoyo_put_name(name);
 339                        goto out;
 340                }
 341        }
 342        envp->name = name;
 343        envp->value = value;
 344        return true;
 345out:
 346        return false;
 347}
 348
 349/**
 350 * tomoyo_same_condition - Check for duplicated "struct tomoyo_condition" entry.
 351 *
 352 * @a: Pointer to "struct tomoyo_condition".
 353 * @b: Pointer to "struct tomoyo_condition".
 354 *
 355 * Returns true if @a == @b, false otherwise.
 356 */
 357static inline bool tomoyo_same_condition(const struct tomoyo_condition *a,
 358                                         const struct tomoyo_condition *b)
 359{
 360        return a->size == b->size && a->condc == b->condc &&
 361                a->numbers_count == b->numbers_count &&
 362                a->names_count == b->names_count &&
 363                a->argc == b->argc && a->envc == b->envc &&
 364                a->grant_log == b->grant_log && a->transit == b->transit &&
 365                !memcmp(a + 1, b + 1, a->size - sizeof(*a));
 366}
 367
 368/**
 369 * tomoyo_condition_type - Get condition type.
 370 *
 371 * @word: Keyword string.
 372 *
 373 * Returns one of values in "enum tomoyo_conditions_index" on success,
 374 * TOMOYO_MAX_CONDITION_KEYWORD otherwise.
 375 */
 376static u8 tomoyo_condition_type(const char *word)
 377{
 378        u8 i;
 379
 380        for (i = 0; i < TOMOYO_MAX_CONDITION_KEYWORD; i++) {
 381                if (!strcmp(word, tomoyo_condition_keyword[i]))
 382                        break;
 383        }
 384        return i;
 385}
 386
 387/* Define this to enable debug mode. */
 388/* #define DEBUG_CONDITION */
 389
 390#ifdef DEBUG_CONDITION
 391#define dprintk printk
 392#else
 393#define dprintk(...) do { } while (0)
 394#endif
 395
 396/**
 397 * tomoyo_commit_condition - Commit "struct tomoyo_condition".
 398 *
 399 * @entry: Pointer to "struct tomoyo_condition".
 400 *
 401 * Returns pointer to "struct tomoyo_condition" on success, NULL otherwise.
 402 *
 403 * This function merges duplicated entries. This function returns NULL if
 404 * @entry is not duplicated but memory quota for policy has exceeded.
 405 */
 406static struct tomoyo_condition *tomoyo_commit_condition
 407(struct tomoyo_condition *entry)
 408{
 409        struct tomoyo_condition *ptr;
 410        bool found = false;
 411
 412        if (mutex_lock_interruptible(&tomoyo_policy_lock)) {
 413                dprintk(KERN_WARNING "%u: %s failed\n", __LINE__, __func__);
 414                ptr = NULL;
 415                found = true;
 416                goto out;
 417        }
 418        list_for_each_entry(ptr, &tomoyo_condition_list, head.list) {
 419                if (!tomoyo_same_condition(ptr, entry) ||
 420                    atomic_read(&ptr->head.users) == TOMOYO_GC_IN_PROGRESS)
 421                        continue;
 422                /* Same entry found. Share this entry. */
 423                atomic_inc(&ptr->head.users);
 424                found = true;
 425                break;
 426        }
 427        if (!found) {
 428                if (tomoyo_memory_ok(entry)) {
 429                        atomic_set(&entry->head.users, 1);
 430                        list_add(&entry->head.list, &tomoyo_condition_list);
 431                } else {
 432                        found = true;
 433                        ptr = NULL;
 434                }
 435        }
 436        mutex_unlock(&tomoyo_policy_lock);
 437out:
 438        if (found) {
 439                tomoyo_del_condition(&entry->head.list);
 440                kfree(entry);
 441                entry = ptr;
 442        }
 443        return entry;
 444}
 445
 446/**
 447 * tomoyo_get_transit_preference - Parse domain transition preference for execve().
 448 *
 449 * @param: Pointer to "struct tomoyo_acl_param".
 450 * @e:     Pointer to "struct tomoyo_condition".
 451 *
 452 * Returns the condition string part.
 453 */
 454static char *tomoyo_get_transit_preference(struct tomoyo_acl_param *param,
 455                                           struct tomoyo_condition *e)
 456{
 457        char * const pos = param->data;
 458        bool flag;
 459
 460        if (*pos == '<') {
 461                e->transit = tomoyo_get_domainname(param);
 462                goto done;
 463        }
 464        {
 465                char *cp = strchr(pos, ' ');
 466
 467                if (cp)
 468                        *cp = '\0';
 469                flag = tomoyo_correct_path(pos) || !strcmp(pos, "keep") ||
 470                        !strcmp(pos, "initialize") || !strcmp(pos, "reset") ||
 471                        !strcmp(pos, "child") || !strcmp(pos, "parent");
 472                if (cp)
 473                        *cp = ' ';
 474        }
 475        if (!flag)
 476                return pos;
 477        e->transit = tomoyo_get_name(tomoyo_read_token(param));
 478done:
 479        if (e->transit)
 480                return param->data;
 481        /*
 482         * Return a bad read-only condition string that will let
 483         * tomoyo_get_condition() return NULL.
 484         */
 485        return "/";
 486}
 487
 488/**
 489 * tomoyo_get_condition - Parse condition part.
 490 *
 491 * @param: Pointer to "struct tomoyo_acl_param".
 492 *
 493 * Returns pointer to "struct tomoyo_condition" on success, NULL otherwise.
 494 */
 495struct tomoyo_condition *tomoyo_get_condition(struct tomoyo_acl_param *param)
 496{
 497        struct tomoyo_condition *entry = NULL;
 498        struct tomoyo_condition_element *condp = NULL;
 499        struct tomoyo_number_union *numbers_p = NULL;
 500        struct tomoyo_name_union *names_p = NULL;
 501        struct tomoyo_argv *argv = NULL;
 502        struct tomoyo_envp *envp = NULL;
 503        struct tomoyo_condition e = { };
 504        char * const start_of_string =
 505                tomoyo_get_transit_preference(param, &e);
 506        char * const end_of_string = start_of_string + strlen(start_of_string);
 507        char *pos;
 508
 509rerun:
 510        pos = start_of_string;
 511        while (1) {
 512                u8 left = -1;
 513                u8 right = -1;
 514                char *left_word = pos;
 515                char *cp;
 516                char *right_word;
 517                bool is_not;
 518
 519                if (!*left_word)
 520                        break;
 521                /*
 522                 * Since left-hand condition does not allow use of "path_group"
 523                 * or "number_group" and environment variable's names do not
 524                 * accept '=', it is guaranteed that the original line consists
 525                 * of one or more repetition of $left$operator$right blocks
 526                 * where "$left is free from '=' and ' '" and "$operator is
 527                 * either '=' or '!='" and "$right is free from ' '".
 528                 * Therefore, we can reconstruct the original line at the end
 529                 * of dry run even if we overwrite $operator with '\0'.
 530                 */
 531                cp = strchr(pos, ' ');
 532                if (cp) {
 533                        *cp = '\0'; /* Will restore later. */
 534                        pos = cp + 1;
 535                } else {
 536                        pos = "";
 537                }
 538                right_word = strchr(left_word, '=');
 539                if (!right_word || right_word == left_word)
 540                        goto out;
 541                is_not = *(right_word - 1) == '!';
 542                if (is_not)
 543                        *(right_word++ - 1) = '\0'; /* Will restore later. */
 544                else if (*(right_word + 1) != '=')
 545                        *right_word++ = '\0'; /* Will restore later. */
 546                else
 547                        goto out;
 548                dprintk(KERN_WARNING "%u: <%s>%s=<%s>\n", __LINE__, left_word,
 549                        is_not ? "!" : "", right_word);
 550                if (!strcmp(left_word, "grant_log")) {
 551                        if (entry) {
 552                                if (is_not ||
 553                                    entry->grant_log != TOMOYO_GRANTLOG_AUTO)
 554                                        goto out;
 555                                else if (!strcmp(right_word, "yes"))
 556                                        entry->grant_log = TOMOYO_GRANTLOG_YES;
 557                                else if (!strcmp(right_word, "no"))
 558                                        entry->grant_log = TOMOYO_GRANTLOG_NO;
 559                                else
 560                                        goto out;
 561                        }
 562                        continue;
 563                }
 564                if (!strncmp(left_word, "exec.argv[", 10)) {
 565                        if (!argv) {
 566                                e.argc++;
 567                                e.condc++;
 568                        } else {
 569                                e.argc--;
 570                                e.condc--;
 571                                left = TOMOYO_ARGV_ENTRY;
 572                                argv->is_not = is_not;
 573                                if (!tomoyo_parse_argv(left_word + 10,
 574                                                       right_word, argv++))
 575                                        goto out;
 576                        }
 577                        goto store_value;
 578                }
 579                if (!strncmp(left_word, "exec.envp[\"", 11)) {
 580                        if (!envp) {
 581                                e.envc++;
 582                                e.condc++;
 583                        } else {
 584                                e.envc--;
 585                                e.condc--;
 586                                left = TOMOYO_ENVP_ENTRY;
 587                                envp->is_not = is_not;
 588                                if (!tomoyo_parse_envp(left_word + 11,
 589                                                       right_word, envp++))
 590                                        goto out;
 591                        }
 592                        goto store_value;
 593                }
 594                left = tomoyo_condition_type(left_word);
 595                dprintk(KERN_WARNING "%u: <%s> left=%u\n", __LINE__, left_word,
 596                        left);
 597                if (left == TOMOYO_MAX_CONDITION_KEYWORD) {
 598                        if (!numbers_p) {
 599                                e.numbers_count++;
 600                        } else {
 601                                e.numbers_count--;
 602                                left = TOMOYO_NUMBER_UNION;
 603                                param->data = left_word;
 604                                if (*left_word == '@' ||
 605                                    !tomoyo_parse_number_union(param,
 606                                                               numbers_p++))
 607                                        goto out;
 608                        }
 609                }
 610                if (!condp)
 611                        e.condc++;
 612                else
 613                        e.condc--;
 614                if (left == TOMOYO_EXEC_REALPATH ||
 615                    left == TOMOYO_SYMLINK_TARGET) {
 616                        if (!names_p) {
 617                                e.names_count++;
 618                        } else {
 619                                e.names_count--;
 620                                right = TOMOYO_NAME_UNION;
 621                                param->data = right_word;
 622                                if (!tomoyo_parse_name_union_quoted(param,
 623                                                                    names_p++))
 624                                        goto out;
 625                        }
 626                        goto store_value;
 627                }
 628                right = tomoyo_condition_type(right_word);
 629                if (right == TOMOYO_MAX_CONDITION_KEYWORD) {
 630                        if (!numbers_p) {
 631                                e.numbers_count++;
 632                        } else {
 633                                e.numbers_count--;
 634                                right = TOMOYO_NUMBER_UNION;
 635                                param->data = right_word;
 636                                if (!tomoyo_parse_number_union(param,
 637                                                               numbers_p++))
 638                                        goto out;
 639                        }
 640                }
 641store_value:
 642                if (!condp) {
 643                        dprintk(KERN_WARNING "%u: dry_run left=%u right=%u match=%u\n",
 644                                __LINE__, left, right, !is_not);
 645                        continue;
 646                }
 647                condp->left = left;
 648                condp->right = right;
 649                condp->equals = !is_not;
 650                dprintk(KERN_WARNING "%u: left=%u right=%u match=%u\n",
 651                        __LINE__, condp->left, condp->right,
 652                        condp->equals);
 653                condp++;
 654        }
 655        dprintk(KERN_INFO "%u: cond=%u numbers=%u names=%u ac=%u ec=%u\n",
 656                __LINE__, e.condc, e.numbers_count, e.names_count, e.argc,
 657                e.envc);
 658        if (entry) {
 659                BUG_ON(e.names_count | e.numbers_count | e.argc | e.envc |
 660                       e.condc);
 661                return tomoyo_commit_condition(entry);
 662        }
 663        e.size = sizeof(*entry)
 664                + e.condc * sizeof(struct tomoyo_condition_element)
 665                + e.numbers_count * sizeof(struct tomoyo_number_union)
 666                + e.names_count * sizeof(struct tomoyo_name_union)
 667                + e.argc * sizeof(struct tomoyo_argv)
 668                + e.envc * sizeof(struct tomoyo_envp);
 669        entry = kzalloc(e.size, GFP_NOFS);
 670        if (!entry)
 671                goto out2;
 672        *entry = e;
 673        e.transit = NULL;
 674        condp = (struct tomoyo_condition_element *) (entry + 1);
 675        numbers_p = (struct tomoyo_number_union *) (condp + e.condc);
 676        names_p = (struct tomoyo_name_union *) (numbers_p + e.numbers_count);
 677        argv = (struct tomoyo_argv *) (names_p + e.names_count);
 678        envp = (struct tomoyo_envp *) (argv + e.argc);
 679        {
 680                bool flag = false;
 681
 682                for (pos = start_of_string; pos < end_of_string; pos++) {
 683                        if (*pos)
 684                                continue;
 685                        if (flag) /* Restore " ". */
 686                                *pos = ' ';
 687                        else if (*(pos + 1) == '=') /* Restore "!=". */
 688                                *pos = '!';
 689                        else /* Restore "=". */
 690                                *pos = '=';
 691                        flag = !flag;
 692                }
 693        }
 694        goto rerun;
 695out:
 696        dprintk(KERN_WARNING "%u: %s failed\n", __LINE__, __func__);
 697        if (entry) {
 698                tomoyo_del_condition(&entry->head.list);
 699                kfree(entry);
 700        }
 701out2:
 702        tomoyo_put_name(e.transit);
 703        return NULL;
 704}
 705
 706/**
 707 * tomoyo_get_attributes - Revalidate "struct inode".
 708 *
 709 * @obj: Pointer to "struct tomoyo_obj_info".
 710 *
 711 * Returns nothing.
 712 */
 713void tomoyo_get_attributes(struct tomoyo_obj_info *obj)
 714{
 715        u8 i;
 716        struct dentry *dentry = NULL;
 717
 718        for (i = 0; i < TOMOYO_MAX_PATH_STAT; i++) {
 719                struct inode *inode;
 720
 721                switch (i) {
 722                case TOMOYO_PATH1:
 723                        dentry = obj->path1.dentry;
 724                        if (!dentry)
 725                                continue;
 726                        break;
 727                case TOMOYO_PATH2:
 728                        dentry = obj->path2.dentry;
 729                        if (!dentry)
 730                                continue;
 731                        break;
 732                default:
 733                        if (!dentry)
 734                                continue;
 735                        dentry = dget_parent(dentry);
 736                        break;
 737                }
 738                inode = d_backing_inode(dentry);
 739                if (inode) {
 740                        struct tomoyo_mini_stat *stat = &obj->stat[i];
 741
 742                        stat->uid  = inode->i_uid;
 743                        stat->gid  = inode->i_gid;
 744                        stat->ino  = inode->i_ino;
 745                        stat->mode = inode->i_mode;
 746                        stat->dev  = inode->i_sb->s_dev;
 747                        stat->rdev = inode->i_rdev;
 748                        obj->stat_valid[i] = true;
 749                }
 750                if (i & 1) /* TOMOYO_PATH1_PARENT or TOMOYO_PATH2_PARENT */
 751                        dput(dentry);
 752        }
 753}
 754
 755/**
 756 * tomoyo_condition - Check condition part.
 757 *
 758 * @r:    Pointer to "struct tomoyo_request_info".
 759 * @cond: Pointer to "struct tomoyo_condition". Maybe NULL.
 760 *
 761 * Returns true on success, false otherwise.
 762 *
 763 * Caller holds tomoyo_read_lock().
 764 */
 765bool tomoyo_condition(struct tomoyo_request_info *r,
 766                      const struct tomoyo_condition *cond)
 767{
 768        u32 i;
 769        unsigned long min_v[2] = { 0, 0 };
 770        unsigned long max_v[2] = { 0, 0 };
 771        const struct tomoyo_condition_element *condp;
 772        const struct tomoyo_number_union *numbers_p;
 773        const struct tomoyo_name_union *names_p;
 774        const struct tomoyo_argv *argv;
 775        const struct tomoyo_envp *envp;
 776        struct tomoyo_obj_info *obj;
 777        u16 condc;
 778        u16 argc;
 779        u16 envc;
 780        struct linux_binprm *bprm = NULL;
 781
 782        if (!cond)
 783                return true;
 784        condc = cond->condc;
 785        argc = cond->argc;
 786        envc = cond->envc;
 787        obj = r->obj;
 788        if (r->ee)
 789                bprm = r->ee->bprm;
 790        if (!bprm && (argc || envc))
 791                return false;
 792        condp = (struct tomoyo_condition_element *) (cond + 1);
 793        numbers_p = (const struct tomoyo_number_union *) (condp + condc);
 794        names_p = (const struct tomoyo_name_union *)
 795                (numbers_p + cond->numbers_count);
 796        argv = (const struct tomoyo_argv *) (names_p + cond->names_count);
 797        envp = (const struct tomoyo_envp *) (argv + argc);
 798        for (i = 0; i < condc; i++) {
 799                const bool match = condp->equals;
 800                const u8 left = condp->left;
 801                const u8 right = condp->right;
 802                bool is_bitop[2] = { false, false };
 803                u8 j;
 804
 805                condp++;
 806                /* Check argv[] and envp[] later. */
 807                if (left == TOMOYO_ARGV_ENTRY || left == TOMOYO_ENVP_ENTRY)
 808                        continue;
 809                /* Check string expressions. */
 810                if (right == TOMOYO_NAME_UNION) {
 811                        const struct tomoyo_name_union *ptr = names_p++;
 812                        struct tomoyo_path_info *symlink;
 813                        struct tomoyo_execve *ee;
 814                        struct file *file;
 815
 816                        switch (left) {
 817                        case TOMOYO_SYMLINK_TARGET:
 818                                symlink = obj ? obj->symlink_target : NULL;
 819                                if (!symlink ||
 820                                    !tomoyo_compare_name_union(symlink, ptr)
 821                                    == match)
 822                                        goto out;
 823                                break;
 824                        case TOMOYO_EXEC_REALPATH:
 825                                ee = r->ee;
 826                                file = ee ? ee->bprm->file : NULL;
 827                                if (!tomoyo_scan_exec_realpath(file, ptr,
 828                                                               match))
 829                                        goto out;
 830                                break;
 831                        }
 832                        continue;
 833                }
 834                /* Check numeric or bit-op expressions. */
 835                for (j = 0; j < 2; j++) {
 836                        const u8 index = j ? right : left;
 837                        unsigned long value = 0;
 838
 839                        switch (index) {
 840                        case TOMOYO_TASK_UID:
 841                                value = from_kuid(&init_user_ns, current_uid());
 842                                break;
 843                        case TOMOYO_TASK_EUID:
 844                                value = from_kuid(&init_user_ns, current_euid());
 845                                break;
 846                        case TOMOYO_TASK_SUID:
 847                                value = from_kuid(&init_user_ns, current_suid());
 848                                break;
 849                        case TOMOYO_TASK_FSUID:
 850                                value = from_kuid(&init_user_ns, current_fsuid());
 851                                break;
 852                        case TOMOYO_TASK_GID:
 853                                value = from_kgid(&init_user_ns, current_gid());
 854                                break;
 855                        case TOMOYO_TASK_EGID:
 856                                value = from_kgid(&init_user_ns, current_egid());
 857                                break;
 858                        case TOMOYO_TASK_SGID:
 859                                value = from_kgid(&init_user_ns, current_sgid());
 860                                break;
 861                        case TOMOYO_TASK_FSGID:
 862                                value = from_kgid(&init_user_ns, current_fsgid());
 863                                break;
 864                        case TOMOYO_TASK_PID:
 865                                value = tomoyo_sys_getpid();
 866                                break;
 867                        case TOMOYO_TASK_PPID:
 868                                value = tomoyo_sys_getppid();
 869                                break;
 870                        case TOMOYO_TYPE_IS_SOCKET:
 871                                value = S_IFSOCK;
 872                                break;
 873                        case TOMOYO_TYPE_IS_SYMLINK:
 874                                value = S_IFLNK;
 875                                break;
 876                        case TOMOYO_TYPE_IS_FILE:
 877                                value = S_IFREG;
 878                                break;
 879                        case TOMOYO_TYPE_IS_BLOCK_DEV:
 880                                value = S_IFBLK;
 881                                break;
 882                        case TOMOYO_TYPE_IS_DIRECTORY:
 883                                value = S_IFDIR;
 884                                break;
 885                        case TOMOYO_TYPE_IS_CHAR_DEV:
 886                                value = S_IFCHR;
 887                                break;
 888                        case TOMOYO_TYPE_IS_FIFO:
 889                                value = S_IFIFO;
 890                                break;
 891                        case TOMOYO_MODE_SETUID:
 892                                value = S_ISUID;
 893                                break;
 894                        case TOMOYO_MODE_SETGID:
 895                                value = S_ISGID;
 896                                break;
 897                        case TOMOYO_MODE_STICKY:
 898                                value = S_ISVTX;
 899                                break;
 900                        case TOMOYO_MODE_OWNER_READ:
 901                                value = 0400;
 902                                break;
 903                        case TOMOYO_MODE_OWNER_WRITE:
 904                                value = 0200;
 905                                break;
 906                        case TOMOYO_MODE_OWNER_EXECUTE:
 907                                value = 0100;
 908                                break;
 909                        case TOMOYO_MODE_GROUP_READ:
 910                                value = 0040;
 911                                break;
 912                        case TOMOYO_MODE_GROUP_WRITE:
 913                                value = 0020;
 914                                break;
 915                        case TOMOYO_MODE_GROUP_EXECUTE:
 916                                value = 0010;
 917                                break;
 918                        case TOMOYO_MODE_OTHERS_READ:
 919                                value = 0004;
 920                                break;
 921                        case TOMOYO_MODE_OTHERS_WRITE:
 922                                value = 0002;
 923                                break;
 924                        case TOMOYO_MODE_OTHERS_EXECUTE:
 925                                value = 0001;
 926                                break;
 927                        case TOMOYO_EXEC_ARGC:
 928                                if (!bprm)
 929                                        goto out;
 930                                value = bprm->argc;
 931                                break;
 932                        case TOMOYO_EXEC_ENVC:
 933                                if (!bprm)
 934                                        goto out;
 935                                value = bprm->envc;
 936                                break;
 937                        case TOMOYO_NUMBER_UNION:
 938                                /* Fetch values later. */
 939                                break;
 940                        default:
 941                                if (!obj)
 942                                        goto out;
 943                                if (!obj->validate_done) {
 944                                        tomoyo_get_attributes(obj);
 945                                        obj->validate_done = true;
 946                                }
 947                                {
 948                                        u8 stat_index;
 949                                        struct tomoyo_mini_stat *stat;
 950
 951                                        switch (index) {
 952                                        case TOMOYO_PATH1_UID:
 953                                        case TOMOYO_PATH1_GID:
 954                                        case TOMOYO_PATH1_INO:
 955                                        case TOMOYO_PATH1_MAJOR:
 956                                        case TOMOYO_PATH1_MINOR:
 957                                        case TOMOYO_PATH1_TYPE:
 958                                        case TOMOYO_PATH1_DEV_MAJOR:
 959                                        case TOMOYO_PATH1_DEV_MINOR:
 960                                        case TOMOYO_PATH1_PERM:
 961                                                stat_index = TOMOYO_PATH1;
 962                                                break;
 963                                        case TOMOYO_PATH2_UID:
 964                                        case TOMOYO_PATH2_GID:
 965                                        case TOMOYO_PATH2_INO:
 966                                        case TOMOYO_PATH2_MAJOR:
 967                                        case TOMOYO_PATH2_MINOR:
 968                                        case TOMOYO_PATH2_TYPE:
 969                                        case TOMOYO_PATH2_DEV_MAJOR:
 970                                        case TOMOYO_PATH2_DEV_MINOR:
 971                                        case TOMOYO_PATH2_PERM:
 972                                                stat_index = TOMOYO_PATH2;
 973                                                break;
 974                                        case TOMOYO_PATH1_PARENT_UID:
 975                                        case TOMOYO_PATH1_PARENT_GID:
 976                                        case TOMOYO_PATH1_PARENT_INO:
 977                                        case TOMOYO_PATH1_PARENT_PERM:
 978                                                stat_index =
 979                                                        TOMOYO_PATH1_PARENT;
 980                                                break;
 981                                        case TOMOYO_PATH2_PARENT_UID:
 982                                        case TOMOYO_PATH2_PARENT_GID:
 983                                        case TOMOYO_PATH2_PARENT_INO:
 984                                        case TOMOYO_PATH2_PARENT_PERM:
 985                                                stat_index =
 986                                                        TOMOYO_PATH2_PARENT;
 987                                                break;
 988                                        default:
 989                                                goto out;
 990                                        }
 991                                        if (!obj->stat_valid[stat_index])
 992                                                goto out;
 993                                        stat = &obj->stat[stat_index];
 994                                        switch (index) {
 995                                        case TOMOYO_PATH1_UID:
 996                                        case TOMOYO_PATH2_UID:
 997                                        case TOMOYO_PATH1_PARENT_UID:
 998                                        case TOMOYO_PATH2_PARENT_UID:
 999                                                value = from_kuid(&init_user_ns, stat->uid);
1000                                                break;
1001                                        case TOMOYO_PATH1_GID:
1002                                        case TOMOYO_PATH2_GID:
1003                                        case TOMOYO_PATH1_PARENT_GID:
1004                                        case TOMOYO_PATH2_PARENT_GID:
1005                                                value = from_kgid(&init_user_ns, stat->gid);
1006                                                break;
1007                                        case TOMOYO_PATH1_INO:
1008                                        case TOMOYO_PATH2_INO:
1009                                        case TOMOYO_PATH1_PARENT_INO:
1010                                        case TOMOYO_PATH2_PARENT_INO:
1011                                                value = stat->ino;
1012                                                break;
1013                                        case TOMOYO_PATH1_MAJOR:
1014                                        case TOMOYO_PATH2_MAJOR:
1015                                                value = MAJOR(stat->dev);
1016                                                break;
1017                                        case TOMOYO_PATH1_MINOR:
1018                                        case TOMOYO_PATH2_MINOR:
1019                                                value = MINOR(stat->dev);
1020                                                break;
1021                                        case TOMOYO_PATH1_TYPE:
1022                                        case TOMOYO_PATH2_TYPE:
1023                                                value = stat->mode & S_IFMT;
1024                                                break;
1025                                        case TOMOYO_PATH1_DEV_MAJOR:
1026                                        case TOMOYO_PATH2_DEV_MAJOR:
1027                                                value = MAJOR(stat->rdev);
1028                                                break;
1029                                        case TOMOYO_PATH1_DEV_MINOR:
1030                                        case TOMOYO_PATH2_DEV_MINOR:
1031                                                value = MINOR(stat->rdev);
1032                                                break;
1033                                        case TOMOYO_PATH1_PERM:
1034                                        case TOMOYO_PATH2_PERM:
1035                                        case TOMOYO_PATH1_PARENT_PERM:
1036                                        case TOMOYO_PATH2_PARENT_PERM:
1037                                                value = stat->mode & S_IALLUGO;
1038                                                break;
1039                                        }
1040                                }
1041                                break;
1042                        }
1043                        max_v[j] = value;
1044                        min_v[j] = value;
1045                        switch (index) {
1046                        case TOMOYO_MODE_SETUID:
1047                        case TOMOYO_MODE_SETGID:
1048                        case TOMOYO_MODE_STICKY:
1049                        case TOMOYO_MODE_OWNER_READ:
1050                        case TOMOYO_MODE_OWNER_WRITE:
1051                        case TOMOYO_MODE_OWNER_EXECUTE:
1052                        case TOMOYO_MODE_GROUP_READ:
1053                        case TOMOYO_MODE_GROUP_WRITE:
1054                        case TOMOYO_MODE_GROUP_EXECUTE:
1055                        case TOMOYO_MODE_OTHERS_READ:
1056                        case TOMOYO_MODE_OTHERS_WRITE:
1057                        case TOMOYO_MODE_OTHERS_EXECUTE:
1058                                is_bitop[j] = true;
1059                        }
1060                }
1061                if (left == TOMOYO_NUMBER_UNION) {
1062                        /* Fetch values now. */
1063                        const struct tomoyo_number_union *ptr = numbers_p++;
1064
1065                        min_v[0] = ptr->values[0];
1066                        max_v[0] = ptr->values[1];
1067                }
1068                if (right == TOMOYO_NUMBER_UNION) {
1069                        /* Fetch values now. */
1070                        const struct tomoyo_number_union *ptr = numbers_p++;
1071
1072                        if (ptr->group) {
1073                                if (tomoyo_number_matches_group(min_v[0],
1074                                                                max_v[0],
1075                                                                ptr->group)
1076                                    == match)
1077                                        continue;
1078                        } else {
1079                                if ((min_v[0] <= ptr->values[1] &&
1080                                     max_v[0] >= ptr->values[0]) == match)
1081                                        continue;
1082                        }
1083                        goto out;
1084                }
1085                /*
1086                 * Bit operation is valid only when counterpart value
1087                 * represents permission.
1088                 */
1089                if (is_bitop[0] && is_bitop[1]) {
1090                        goto out;
1091                } else if (is_bitop[0]) {
1092                        switch (right) {
1093                        case TOMOYO_PATH1_PERM:
1094                        case TOMOYO_PATH1_PARENT_PERM:
1095                        case TOMOYO_PATH2_PERM:
1096                        case TOMOYO_PATH2_PARENT_PERM:
1097                                if (!(max_v[0] & max_v[1]) == !match)
1098                                        continue;
1099                        }
1100                        goto out;
1101                } else if (is_bitop[1]) {
1102                        switch (left) {
1103                        case TOMOYO_PATH1_PERM:
1104                        case TOMOYO_PATH1_PARENT_PERM:
1105                        case TOMOYO_PATH2_PERM:
1106                        case TOMOYO_PATH2_PARENT_PERM:
1107                                if (!(max_v[0] & max_v[1]) == !match)
1108                                        continue;
1109                        }
1110                        goto out;
1111                }
1112                /* Normal value range comparison. */
1113                if ((min_v[0] <= max_v[1] && max_v[0] >= min_v[1]) == match)
1114                        continue;
1115out:
1116                return false;
1117        }
1118        /* Check argv[] and envp[] now. */
1119        if (r->ee && (argc || envc))
1120                return tomoyo_scan_bprm(r->ee, argc, argv, envc, envp);
1121        return true;
1122}
1123