security/tomoyo/file.c

   1 /*
   2  * security/tomoyo/file.c
   3  *
   4  * Pathname restriction functions.
   5  *
   6  * Copyright (C) 2005-2010  NTT DATA CORPORATION
   7  */
   8
   9 #include "common.h"
  10 #include <linux/slab.h>
  11
  12 /* Keyword array for operations with one pathname. */
  13 static const char *tomoyo_path_keyword[TOMOYO_MAX_PATH_OPERATION] = {
  14         [TOMOYO_TYPE_READ_WRITE] = "read/write",
  15         [TOMOYO_TYPE_EXECUTE]    = "execute",
  16         [TOMOYO_TYPE_READ]       = "read",
  17         [TOMOYO_TYPE_WRITE]      = "write",
  18         [TOMOYO_TYPE_UNLINK]     = "unlink",
  19         [TOMOYO_TYPE_RMDIR]      = "rmdir",
  20         [TOMOYO_TYPE_TRUNCATE]   = "truncate",
  21         [TOMOYO_TYPE_SYMLINK]    = "symlink",
  22         [TOMOYO_TYPE_REWRITE]    = "rewrite",
  23         [TOMOYO_TYPE_CHROOT]     = "chroot",
  24         [TOMOYO_TYPE_UMOUNT]     = "unmount",
  25 };
  26
  27 /* Keyword array for operations with one pathname and three numbers. */
  28 static const char *tomoyo_path_number3_keyword
  29 [TOMOYO_MAX_PATH_NUMBER3_OPERATION] = {
  30         [TOMOYO_TYPE_MKBLOCK]    = "mkblock",
  31         [TOMOYO_TYPE_MKCHAR]     = "mkchar",
  32 };
  33
  34 /* Keyword array for operations with two pathnames. */
  35 static const char *tomoyo_path2_keyword[TOMOYO_MAX_PATH2_OPERATION] = {
  36         [TOMOYO_TYPE_LINK]       = "link",
  37         [TOMOYO_TYPE_RENAME]     = "rename",
  38         [TOMOYO_TYPE_PIVOT_ROOT] = "pivot_root",
  39 };
  40
  41 /* Keyword array for operations with one pathname and one number. */
  42 static const char *tomoyo_path_number_keyword
  43 [TOMOYO_MAX_PATH_NUMBER_OPERATION] = {
  44         [TOMOYO_TYPE_CREATE]     = "create",
  45         [TOMOYO_TYPE_MKDIR]      = "mkdir",
  46         [TOMOYO_TYPE_MKFIFO]     = "mkfifo",
  47         [TOMOYO_TYPE_MKSOCK]     = "mksock",
  48         [TOMOYO_TYPE_IOCTL]      = "ioctl",
  49         [TOMOYO_TYPE_CHMOD]      = "chmod",
  50         [TOMOYO_TYPE_CHOWN]      = "chown",
  51         [TOMOYO_TYPE_CHGRP]      = "chgrp",
  52 };
  53
  54 static const u8 tomoyo_p2mac[TOMOYO_MAX_PATH_OPERATION] = {
  55         [TOMOYO_TYPE_READ_WRITE] = TOMOYO_MAC_FILE_OPEN,
  56         [TOMOYO_TYPE_EXECUTE]    = TOMOYO_MAC_FILE_EXECUTE,
  57         [TOMOYO_TYPE_READ]       = TOMOYO_MAC_FILE_OPEN,
  58         [TOMOYO_TYPE_WRITE]      = TOMOYO_MAC_FILE_OPEN,
  59         [TOMOYO_TYPE_UNLINK]     = TOMOYO_MAC_FILE_UNLINK,
  60         [TOMOYO_TYPE_RMDIR]      = TOMOYO_MAC_FILE_RMDIR,
  61         [TOMOYO_TYPE_TRUNCATE]   = TOMOYO_MAC_FILE_TRUNCATE,
  62         [TOMOYO_TYPE_SYMLINK]    = TOMOYO_MAC_FILE_SYMLINK,
  63         [TOMOYO_TYPE_REWRITE]    = TOMOYO_MAC_FILE_REWRITE,
  64         [TOMOYO_TYPE_CHROOT]     = TOMOYO_MAC_FILE_CHROOT,
  65         [TOMOYO_TYPE_UMOUNT]     = TOMOYO_MAC_FILE_UMOUNT,
  66 };
  67
  68 static const u8 tomoyo_pnnn2mac[TOMOYO_MAX_PATH_NUMBER3_OPERATION] = {
  69         [TOMOYO_TYPE_MKBLOCK] = TOMOYO_MAC_FILE_MKBLOCK,
  70         [TOMOYO_TYPE_MKCHAR]  = TOMOYO_MAC_FILE_MKCHAR,
  71 };
  72
  73 static const u8 tomoyo_pp2mac[TOMOYO_MAX_PATH2_OPERATION] = {
  74         [TOMOYO_TYPE_LINK]       = TOMOYO_MAC_FILE_LINK,
  75         [TOMOYO_TYPE_RENAME]     = TOMOYO_MAC_FILE_RENAME,
  76         [TOMOYO_TYPE_PIVOT_ROOT] = TOMOYO_MAC_FILE_PIVOT_ROOT,
  77 };
  78
  79 static const u8 tomoyo_pn2mac[TOMOYO_MAX_PATH_NUMBER_OPERATION] = {
  80         [TOMOYO_TYPE_CREATE] = TOMOYO_MAC_FILE_CREATE,
  81         [TOMOYO_TYPE_MKDIR]  = TOMOYO_MAC_FILE_MKDIR,
  82         [TOMOYO_TYPE_MKFIFO] = TOMOYO_MAC_FILE_MKFIFO,
  83         [TOMOYO_TYPE_MKSOCK] = TOMOYO_MAC_FILE_MKSOCK,
  84         [TOMOYO_TYPE_IOCTL]  = TOMOYO_MAC_FILE_IOCTL,
  85         [TOMOYO_TYPE_CHMOD]  = TOMOYO_MAC_FILE_CHMOD,
  86         [TOMOYO_TYPE_CHOWN]  = TOMOYO_MAC_FILE_CHOWN,
  87         [TOMOYO_TYPE_CHGRP]  = TOMOYO_MAC_FILE_CHGRP,
  88 };
  89
  90 void tomoyo_put_name_union(struct tomoyo_name_union *ptr)
  91 {
  92         if (!ptr)
  93                 return;
  94         if (ptr->is_group)
  95                 tomoyo_put_path_group(ptr->group);
  96         else
  97                 tomoyo_put_name(ptr->filename);
  98 }
  99
 100 bool tomoyo_compare_name_union(const struct tomoyo_path_info *name,
 101                                const struct tomoyo_name_union *ptr)
 102 {
 103         if (ptr->is_group)
 104                 return tomoyo_path_matches_group(name, ptr->group);
 105         return tomoyo_path_matches_pattern(name, ptr->filename);
 106 }
 107
 108 void tomoyo_put_number_union(struct tomoyo_number_union *ptr)
 109 {
 110         if (ptr && ptr->is_group)
 111                 tomoyo_put_number_group(ptr->group);
 112 }
 113
 114 bool tomoyo_compare_number_union(const unsigned long value,
 115                                  const struct tomoyo_number_union *ptr)
 116 {
 117         if (ptr->is_group)
 118                 return tomoyo_number_matches_group(value, value, ptr->group);
 119         return value >= ptr->values[0] && value <= ptr->values[1];
 120 }
 121
 122 /**
 123  * tomoyo_path2keyword - Get the name of single path operation.
 124  *
 125  * @operation: Type of operation.
 126  *
 127  * Returns the name of single path operation.
 128  */
 129 const char *tomoyo_path2keyword(const u8 operation)
 130 {
 131         return (operation < TOMOYO_MAX_PATH_OPERATION)
 132                 ? tomoyo_path_keyword[operation] : NULL;
 133 }
 134
 135 /**
 136  * tomoyo_path_number32keyword - Get the name of path/number/number/number operations.
 137  *
 138  * @operation: Type of operation.
 139  *
 140  * Returns the name of path/number/number/number operation.
 141  */
 142 const char *tomoyo_path_number32keyword(const u8 operation)
 143 {
 144         return (operation < TOMOYO_MAX_PATH_NUMBER3_OPERATION)
 145                 ? tomoyo_path_number3_keyword[operation] : NULL;
 146 }
 147
 148 /**
 149  * tomoyo_path22keyword - Get the name of double path operation.
 150  *
 151  * @operation: Type of operation.
 152  *
 153  * Returns the name of double path operation.
 154  */
 155 const char *tomoyo_path22keyword(const u8 operation)
 156 {
 157         return (operation < TOMOYO_MAX_PATH2_OPERATION)
 158                 ? tomoyo_path2_keyword[operation] : NULL;
 159 }
 160
 161 /**
 162  * tomoyo_path_number2keyword - Get the name of path/number operations.
 163  *
 164  * @operation: Type of operation.
 165  *
 166  * Returns the name of path/number operation.
 167  */
 168 const char *tomoyo_path_number2keyword(const u8 operation)
 169 {
 170         return (operation < TOMOYO_MAX_PATH_NUMBER_OPERATION)
 171                 ? tomoyo_path_number_keyword[operation] : NULL;
 172 }
 173
 174 static void tomoyo_add_slash(struct tomoyo_path_info *buf)
 175 {
 176         if (buf->is_dir)
 177                 return;
 178         /*
 179          * This is OK because tomoyo_encode() reserves space for appending "/".
 180          */
 181         strcat((char *) buf->name, "/");
 182         tomoyo_fill_path_info(buf);
 183 }
 184
 185 /**
 186  * tomoyo_strendswith - Check whether the token ends with the given token.
 187  *
 188  * @name: The token to check.
 189  * @tail: The token to find.
 190  *
 191  * Returns true if @name ends with @tail, false otherwise.
 192  */
 193 static bool tomoyo_strendswith(const char *name, const char *tail)
 194 {
 195         int len;
 196
 197         if (!name || !tail)
 198                 return false;
 199         len = strlen(name) - strlen(tail);
 200         return len >= 0 && !strcmp(name + len, tail);
 201 }
 202
 203 /**
 204  * tomoyo_get_realpath - Get realpath.
 205  *
 206  * @buf:  Pointer to "struct tomoyo_path_info".
 207  * @path: Pointer to "struct path".
 208  *
 209  * Returns true on success, false otherwise.
 210  */
 211 static bool tomoyo_get_realpath(struct tomoyo_path_info *buf, struct path *path)
 212 {
 213         buf->name = tomoyo_realpath_from_path(path);
 214         if (buf->name) {
 215                 tomoyo_fill_path_info(buf);
 216                 return true;
 217         }
 218         return false;
 219 }
 220
 221 static int tomoyo_update_path2_acl(const u8 type, const char *filename1,
 222                                    const char *filename2,
 223                                    struct tomoyo_domain_info *const domain,
 224                                    const bool is_delete);
 225 static int tomoyo_update_path_acl(const u8 type, const char *filename,
 226                                   struct tomoyo_domain_info *const domain,
 227                                   const bool is_delete);
 228
 229 /*
 230  * tomoyo_globally_readable_list is used for holding list of pathnames which
 231  * are by default allowed to be open()ed for reading by any process.
 232  *
 233  * An entry is added by
 234  *
 235  * # echo 'allow_read /lib/libc-2.5.so' > \
 236  *                               /sys/kernel/security/tomoyo/exception_policy
 237  *
 238  * and is deleted by
 239  *
 240  * # echo 'delete allow_read /lib/libc-2.5.so' > \
 241  *                               /sys/kernel/security/tomoyo/exception_policy
 242  *
 243  * and all entries are retrieved by
 244  *
 245  * # grep ^allow_read /sys/kernel/security/tomoyo/exception_policy
 246  *
 247  * In the example above, any process is allowed to
 248  * open("/lib/libc-2.5.so", O_RDONLY).
 249  * One exception is, if the domain which current process belongs to is marked
 250  * as "ignore_global_allow_read", current process can't do so unless explicitly
 251  * given "allow_read /lib/libc-2.5.so" to the domain which current process
 252  * belongs to.
 253  */
 254 LIST_HEAD(tomoyo_globally_readable_list);
 255
 256 static bool tomoyo_same_globally_readable(const struct tomoyo_acl_head *a,
 257                                           const struct tomoyo_acl_head *b)
 258 {
 259         return container_of(a, struct tomoyo_globally_readable_file_entry,
 260                             head)->filename ==
 261                 container_of(b, struct tomoyo_globally_readable_file_entry,
 262                              head)->filename;
 263 }
 264
 265 /**
 266  * tomoyo_update_globally_readable_entry - Update "struct tomoyo_globally_readable_file_entry" list.
 267  *
 268  * @filename:  Filename unconditionally permitted to open() for reading.
 269  * @is_delete: True if it is a delete request.
 270  *
 271  * Returns 0 on success, negative value otherwise.
 272  *
 273  * Caller holds tomoyo_read_lock().
 274  */
 275 static int tomoyo_update_globally_readable_entry(const char *filename,
 276                                                  const bool is_delete)
 277 {
 278         struct tomoyo_globally_readable_file_entry e = { };
 279         int error;
 280
 281         if (!tomoyo_is_correct_word(filename))
 282                 return -EINVAL;
 283         e.filename = tomoyo_get_name(filename);
 284         if (!e.filename)
 285                 return -ENOMEM;
 286         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
 287                                      &tomoyo_globally_readable_list,
 288                                      tomoyo_same_globally_readable);
 289         tomoyo_put_name(e.filename);
 290         return error;
 291 }
 292
 293 /**
 294  * tomoyo_is_globally_readable_file - Check if the file is unconditionnaly permitted to be open()ed for reading.
 295  *
 296  * @filename: The filename to check.
 297  *
 298  * Returns true if any domain can open @filename for reading, false otherwise.
 299  *
 300  * Caller holds tomoyo_read_lock().
 301  */
 302 static bool tomoyo_is_globally_readable_file(const struct tomoyo_path_info *
 303                                              filename)
 304 {
 305         struct tomoyo_globally_readable_file_entry *ptr;
 306         bool found = false;
 307
 308         list_for_each_entry_rcu(ptr, &tomoyo_globally_readable_list,
 309                                 head.list) {
 310                 if (!ptr->head.is_deleted &&
 311                     tomoyo_path_matches_pattern(filename, ptr->filename)) {
 312                         found = true;
 313                         break;
 314                 }
 315         }
 316         return found;
 317 }
 318
 319 /**
 320  * tomoyo_write_globally_readable_policy - Write "struct tomoyo_globally_readable_file_entry" list.
 321  *
 322  * @data:      String to parse.
 323  * @is_delete: True if it is a delete request.
 324  *
 325  * Returns 0 on success, negative value otherwise.
 326  *
 327  * Caller holds tomoyo_read_lock().
 328  */
 329 int tomoyo_write_globally_readable_policy(char *data, const bool is_delete)
 330 {
 331         return tomoyo_update_globally_readable_entry(data, is_delete);
 332 }
 333
 334 /**
 335  * tomoyo_read_globally_readable_policy - Read "struct tomoyo_globally_readable_file_entry" list.
 336  *
 337  * @head: Pointer to "struct tomoyo_io_buffer".
 338  *
 339  * Returns true on success, false otherwise.
 340  *
 341  * Caller holds tomoyo_read_lock().
 342  */
 343 bool tomoyo_read_globally_readable_policy(struct tomoyo_io_buffer *head)
 344 {
 345         struct list_head *pos;
 346         bool done = true;
 347
 348         list_for_each_cookie(pos, head->read_var2,
 349                              &tomoyo_globally_readable_list) {
 350                 struct tomoyo_globally_readable_file_entry *ptr;
 351                 ptr = list_entry(pos,
 352                                  struct tomoyo_globally_readable_file_entry,
 353                                  head.list);
 354                 if (ptr->head.is_deleted)
 355                         continue;
 356                 done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_READ "%s\n",
 357                                         ptr->filename->name);
 358                 if (!done)
 359                         break;
 360         }
 361         return done;
 362 }
 363
 364 /* tomoyo_pattern_list is used for holding list of pathnames which are used for
 365  * converting pathnames to pathname patterns during learning mode.
 366  *
 367  * An entry is added by
 368  *
 369  * # echo 'file_pattern /proc/\$/mounts' > \
 370  *                             /sys/kernel/security/tomoyo/exception_policy
 371  *
 372  * and is deleted by
 373  *
 374  * # echo 'delete file_pattern /proc/\$/mounts' > \
 375  *                             /sys/kernel/security/tomoyo/exception_policy
 376  *
 377  * and all entries are retrieved by
 378  *
 379  * # grep ^file_pattern /sys/kernel/security/tomoyo/exception_policy
 380  *
 381  * In the example above, if a process which belongs to a domain which is in
 382  * learning mode requested open("/proc/1/mounts", O_RDONLY),
 383  * "allow_read /proc/\$/mounts" is automatically added to the domain which that
 384  * process belongs to.
 385  *
 386  * It is not a desirable behavior that we have to use /proc/\$/ instead of
 387  * /proc/self/ when current process needs to access only current process's
 388  * information. As of now, LSM version of TOMOYO is using __d_path() for
 389  * calculating pathname. Non LSM version of TOMOYO is using its own function
 390  * which pretends as if /proc/self/ is not a symlink; so that we can forbid
 391  * current process from accessing other process's information.
 392  */
 393 LIST_HEAD(tomoyo_pattern_list);
 394
 395 static bool tomoyo_same_pattern(const struct tomoyo_acl_head *a,
 396                                 const struct tomoyo_acl_head *b)
 397 {
 398         return container_of(a, struct tomoyo_pattern_entry, head)->pattern ==
 399                 container_of(b, struct tomoyo_pattern_entry, head)->pattern;
 400 }
 401
 402 /**
 403  * tomoyo_update_file_pattern_entry - Update "struct tomoyo_pattern_entry" list.
 404  *
 405  * @pattern:   Pathname pattern.
 406  * @is_delete: True if it is a delete request.
 407  *
 408  * Returns 0 on success, negative value otherwise.
 409  *
 410  * Caller holds tomoyo_read_lock().
 411  */
 412 static int tomoyo_update_file_pattern_entry(const char *pattern,
 413                                             const bool is_delete)
 414 {
 415         struct tomoyo_pattern_entry e = { };
 416         int error;
 417
 418         if (!tomoyo_is_correct_word(pattern))
 419                 return -EINVAL;
 420         e.pattern = tomoyo_get_name(pattern);
 421         if (!e.pattern)
 422                 return -ENOMEM;
 423         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
 424                                      &tomoyo_pattern_list,
 425                                      tomoyo_same_pattern);
 426         tomoyo_put_name(e.pattern);
 427         return error;
 428 }
 429
 430 /**
 431  * tomoyo_file_pattern - Get patterned pathname.
 432  *
 433  * @filename: The filename to find patterned pathname.
 434  *
 435  * Returns pointer to pathname pattern if matched, @filename otherwise.
 436  *
 437  * Caller holds tomoyo_read_lock().
 438  */
 439 const char *tomoyo_file_pattern(const struct tomoyo_path_info *filename)
 440 {
 441         struct tomoyo_pattern_entry *ptr;
 442         const struct tomoyo_path_info *pattern = NULL;
 443
 444         list_for_each_entry_rcu(ptr, &tomoyo_pattern_list, head.list) {
 445                 if (ptr->head.is_deleted)
 446                         continue;
 447                 if (!tomoyo_path_matches_pattern(filename, ptr->pattern))
 448                         continue;
 449                 pattern = ptr->pattern;
 450                 if (tomoyo_strendswith(pattern->name, "/\\*")) {
 451                         /* Do nothing. Try to find the better match. */
 452                 } else {
 453                         /* This would be the better match. Use this. */
 454                         break;
 455                 }
 456         }
 457         if (pattern)
 458                 filename = pattern;
 459         return filename->name;
 460 }
 461
 462 /**
 463  * tomoyo_write_pattern_policy - Write "struct tomoyo_pattern_entry" list.
 464  *
 465  * @data:      String to parse.
 466  * @is_delete: True if it is a delete request.
 467  *
 468  * Returns 0 on success, negative value otherwise.
 469  *
 470  * Caller holds tomoyo_read_lock().
 471  */
 472 int tomoyo_write_pattern_policy(char *data, const bool is_delete)
 473 {
 474         return tomoyo_update_file_pattern_entry(data, is_delete);
 475 }
 476
 477 /**
 478  * tomoyo_read_file_pattern - Read "struct tomoyo_pattern_entry" list.
 479  *
 480  * @head: Pointer to "struct tomoyo_io_buffer".
 481  *
 482  * Returns true on success, false otherwise.
 483  *
 484  * Caller holds tomoyo_read_lock().
 485  */
 486 bool tomoyo_read_file_pattern(struct tomoyo_io_buffer *head)
 487 {
 488         struct list_head *pos;
 489         bool done = true;
 490
 491         list_for_each_cookie(pos, head->read_var2, &tomoyo_pattern_list) {
 492                 struct tomoyo_pattern_entry *ptr;
 493                 ptr = list_entry(pos, struct tomoyo_pattern_entry, head.list);
 494                 if (ptr->head.is_deleted)
 495                         continue;
 496                 done = tomoyo_io_printf(head, TOMOYO_KEYWORD_FILE_PATTERN
 497                                         "%s\n", ptr->pattern->name);
 498                 if (!done)
 499                         break;
 500         }
 501         return done;
 502 }
 503
 504 /*
 505  * tomoyo_no_rewrite_list is used for holding list of pathnames which are by
 506  * default forbidden to modify already written content of a file.
 507  *
 508  * An entry is added by
 509  *
 510  * # echo 'deny_rewrite /var/log/messages' > \
 511  *                              /sys/kernel/security/tomoyo/exception_policy
 512  *
 513  * and is deleted by
 514  *
 515  * # echo 'delete deny_rewrite /var/log/messages' > \
 516  *                              /sys/kernel/security/tomoyo/exception_policy
 517  *
 518  * and all entries are retrieved by
 519  *
 520  * # grep ^deny_rewrite /sys/kernel/security/tomoyo/exception_policy
 521  *
 522  * In the example above, if a process requested to rewrite /var/log/messages ,
 523  * the process can't rewrite unless the domain which that process belongs to
 524  * has "allow_rewrite /var/log/messages" entry.
 525  *
 526  * It is not a desirable behavior that we have to add "\040(deleted)" suffix
 527  * when we want to allow rewriting already unlink()ed file. As of now,
 528  * LSM version of TOMOYO is using __d_path() for calculating pathname.
 529  * Non LSM version of TOMOYO is using its own function which doesn't append
 530  * " (deleted)" suffix if the file is already unlink()ed; so that we don't
 531  * need to worry whether the file is already unlink()ed or not.
 532  */
 533 LIST_HEAD(tomoyo_no_rewrite_list);
 534
 535 static bool tomoyo_same_no_rewrite(const struct tomoyo_acl_head *a,
 536                                    const struct tomoyo_acl_head *b)
 537 {
 538         return container_of(a, struct tomoyo_no_rewrite_entry, head)->pattern
 539                 == container_of(b, struct tomoyo_no_rewrite_entry, head)
 540                 ->pattern;
 541 }
 542
 543 /**
 544  * tomoyo_update_no_rewrite_entry - Update "struct tomoyo_no_rewrite_entry" list.
 545  *
 546  * @pattern:   Pathname pattern that are not rewritable by default.
 547  * @is_delete: True if it is a delete request.
 548  *
 549  * Returns 0 on success, negative value otherwise.
 550  *
 551  * Caller holds tomoyo_read_lock().
 552  */
 553 static int tomoyo_update_no_rewrite_entry(const char *pattern,
 554                                           const bool is_delete)
 555 {
 556         struct tomoyo_no_rewrite_entry e = { };
 557         int error;
 558
 559         if (!tomoyo_is_correct_word(pattern))
 560                 return -EINVAL;
 561         e.pattern = tomoyo_get_name(pattern);
 562         if (!e.pattern)
 563                 return -ENOMEM;
 564         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
 565                                      &tomoyo_no_rewrite_list,
 566                                      tomoyo_same_no_rewrite);
 567         tomoyo_put_name(e.pattern);
 568         return error;
 569 }
 570
 571 /**
 572  * tomoyo_is_no_rewrite_file - Check if the given pathname is not permitted to be rewrited.
 573  *
 574  * @filename: Filename to check.
 575  *
 576  * Returns true if @filename is specified by "deny_rewrite" directive,
 577  * false otherwise.
 578  *
 579  * Caller holds tomoyo_read_lock().
 580  */
 581 static bool tomoyo_is_no_rewrite_file(const struct tomoyo_path_info *filename)
 582 {
 583         struct tomoyo_no_rewrite_entry *ptr;
 584         bool found = false;
 585
 586         list_for_each_entry_rcu(ptr, &tomoyo_no_rewrite_list, head.list) {
 587                 if (ptr->head.is_deleted)
 588                         continue;
 589                 if (!tomoyo_path_matches_pattern(filename, ptr->pattern))
 590                         continue;
 591                 found = true;
 592                 break;
 593         }
 594         return found;
 595 }
 596
 597 /**
 598  * tomoyo_write_no_rewrite_policy - Write "struct tomoyo_no_rewrite_entry" list.
 599  *
 600  * @data:      String to parse.
 601  * @is_delete: True if it is a delete request.
 602  *
 603  * Returns 0 on success, negative value otherwise.
 604  *
 605  * Caller holds tomoyo_read_lock().
 606  */
 607 int tomoyo_write_no_rewrite_policy(char *data, const bool is_delete)
 608 {
 609         return tomoyo_update_no_rewrite_entry(data, is_delete);
 610 }
 611
 612 /**
 613  * tomoyo_read_no_rewrite_policy - Read "struct tomoyo_no_rewrite_entry" list.
 614  *
 615  * @head: Pointer to "struct tomoyo_io_buffer".
 616  *
 617  * Returns true on success, false otherwise.
 618  *
 619  * Caller holds tomoyo_read_lock().
 620  */
 621 bool tomoyo_read_no_rewrite_policy(struct tomoyo_io_buffer *head)
 622 {
 623         struct list_head *pos;
 624         bool done = true;
 625
 626         list_for_each_cookie(pos, head->read_var2, &tomoyo_no_rewrite_list) {
 627                 struct tomoyo_no_rewrite_entry *ptr;
 628                 ptr = list_entry(pos, struct tomoyo_no_rewrite_entry,
 629                                  head.list);
 630                 if (ptr->head.is_deleted)
 631                         continue;
 632                 done = tomoyo_io_printf(head, TOMOYO_KEYWORD_DENY_REWRITE
 633                                         "%s\n", ptr->pattern->name);
 634                 if (!done)
 635                         break;
 636         }
 637         return done;
 638 }
 639
 640 /**
 641  * tomoyo_path_acl - Check permission for single path operation.
 642  *
 643  * @r:               Pointer to "struct tomoyo_request_info".
 644  * @filename:        Filename to check.
 645  * @perm:            Permission.
 646  *
 647  * Returns 0 on success, -EPERM otherwise.
 648  *
 649  * Caller holds tomoyo_read_lock().
 650  */
 651 static int tomoyo_path_acl(const struct tomoyo_request_info *r,
 652                            const struct tomoyo_path_info *filename,
 653                            const u32 perm)
 654 {
 655         struct tomoyo_domain_info *domain = r->domain;
 656         struct tomoyo_acl_info *ptr;
 657         int error = -EPERM;
 658
 659         list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
 660                 struct tomoyo_path_acl *acl;
 661                 if (ptr->type != TOMOYO_TYPE_PATH_ACL)
 662                         continue;
 663                 acl = container_of(ptr, struct tomoyo_path_acl, head);
 664                 if (!(acl->perm & perm) ||
 665                     !tomoyo_compare_name_union(filename, &acl->name))
 666                         continue;
 667                 error = 0;
 668                 break;
 669         }
 670         return error;
 671 }
 672
 673 static bool tomoyo_same_path_acl(const struct tomoyo_acl_info *a,
 674                                  const struct tomoyo_acl_info *b)
 675 {
 676         const struct tomoyo_path_acl *p1 = container_of(a, typeof(*p1), head);
 677         const struct tomoyo_path_acl *p2 = container_of(b, typeof(*p2), head);
 678         return tomoyo_is_same_acl_head(&p1->head, &p2->head) &&
 679                 tomoyo_is_same_name_union(&p1->name, &p2->name);
 680 }
 681
 682 static bool tomoyo_merge_path_acl(struct tomoyo_acl_info *a,
 683                                   struct tomoyo_acl_info *b,
 684                                   const bool is_delete)
 685 {
 686         u16 * const a_perm = &container_of(a, struct tomoyo_path_acl, head)
 687                 ->perm;
 688         u16 perm = *a_perm;
 689         const u16 b_perm = container_of(b, struct tomoyo_path_acl, head)->perm;
 690         if (is_delete) {
 691                 perm &= ~b_perm;
 692                 if ((perm & TOMOYO_RW_MASK) != TOMOYO_RW_MASK)
 693                         perm &= ~(1 << TOMOYO_TYPE_READ_WRITE);
 694                 else if (!(perm & (1 << TOMOYO_TYPE_READ_WRITE)))
 695                         perm &= ~TOMOYO_RW_MASK;
 696         } else {
 697                 perm |= b_perm;
 698                 if ((perm & TOMOYO_RW_MASK) == TOMOYO_RW_MASK)
 699                         perm |= (1 << TOMOYO_TYPE_READ_WRITE);
 700                 else if (perm & (1 << TOMOYO_TYPE_READ_WRITE))
 701                         perm |= TOMOYO_RW_MASK;
 702         }
 703         *a_perm = perm;
 704         return !perm;
 705 }
 706
 707 /**
 708  * tomoyo_update_path_acl - Update "struct tomoyo_path_acl" list.
 709  *
 710  * @type:      Type of operation.
 711  * @filename:  Filename.
 712  * @domain:    Pointer to "struct tomoyo_domain_info".
 713  * @is_delete: True if it is a delete request.
 714  *
 715  * Returns 0 on success, negative value otherwise.
 716  *
 717  * Caller holds tomoyo_read_lock().
 718  */
 719 static int tomoyo_update_path_acl(const u8 type, const char *filename,
 720                                   struct tomoyo_domain_info * const domain,
 721                                   const bool is_delete)
 722 {
 723         struct tomoyo_path_acl e = {
 724                 .head.type = TOMOYO_TYPE_PATH_ACL,
 725                 .perm = 1 << type
 726         };
 727         int error;
 728         if (e.perm == (1 << TOMOYO_TYPE_READ_WRITE))
 729                 e.perm |= TOMOYO_RW_MASK;
 730         if (!tomoyo_parse_name_union(filename, &e.name))
 731                 return -EINVAL;
 732         error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
 733                                      tomoyo_same_path_acl,
 734                                      tomoyo_merge_path_acl);
 735         tomoyo_put_name_union(&e.name);
 736         return error;
 737 }
 738
 739 static bool tomoyo_same_path_number3_acl(const struct tomoyo_acl_info *a,
 740                                          const struct tomoyo_acl_info *b)
 741 {
 742         const struct tomoyo_path_number3_acl *p1 = container_of(a, typeof(*p1),
 743                                                                 head);
 744         const struct tomoyo_path_number3_acl *p2 = container_of(b, typeof(*p2),
 745                                                                 head);
 746         return tomoyo_is_same_acl_head(&p1->head, &p2->head)
 747                 && tomoyo_is_same_name_union(&p1->name, &p2->name)
 748                 && tomoyo_is_same_number_union(&p1->mode, &p2->mode)
 749                 && tomoyo_is_same_number_union(&p1->major, &p2->major)
 750                 && tomoyo_is_same_number_union(&p1->minor, &p2->minor);
 751 }
 752
 753 static bool tomoyo_merge_path_number3_acl(struct tomoyo_acl_info *a,
 754                                           struct tomoyo_acl_info *b,
 755                                           const bool is_delete)
 756 {
 757         u8 *const a_perm = &container_of(a, struct tomoyo_path_number3_acl,
 758                                          head)->perm;
 759         u8 perm = *a_perm;
 760         const u8 b_perm = container_of(b, struct tomoyo_path_number3_acl, head)
 761                 ->perm;
 762         if (is_delete)
 763                 perm &= ~b_perm;
 764         else
 765                 perm |= b_perm;
 766         *a_perm = perm;
 767         return !perm;
 768 }
 769
 770 /**
 771  * tomoyo_update_path_number3_acl - Update "struct tomoyo_path_number3_acl" list.
 772  *
 773  * @type:      Type of operation.
 774  * @filename:  Filename.
 775  * @mode:      Create mode.
 776  * @major:     Device major number.
 777  * @minor:     Device minor number.
 778  * @domain:    Pointer to "struct tomoyo_domain_info".
 779  * @is_delete: True if it is a delete request.
 780  *
 781  * Returns 0 on success, negative value otherwise.
 782  *
 783  * Caller holds tomoyo_read_lock().
 784  */
 785 static int tomoyo_update_path_number3_acl(const u8 type, const char *filename,
 786                                           char *mode, char *major, char *minor,
 787                                           struct tomoyo_domain_info * const
 788                                           domain, const bool is_delete)
 789 {
 790         struct tomoyo_path_number3_acl e = {
 791                 .head.type = TOMOYO_TYPE_PATH_NUMBER3_ACL,
 792                 .perm = 1 << type
 793         };
 794         int error = is_delete ? -ENOENT : -ENOMEM;
 795         if (!tomoyo_parse_name_union(filename, &e.name) ||
 796             !tomoyo_parse_number_union(mode, &e.mode) ||
 797             !tomoyo_parse_number_union(major, &e.major) ||
 798             !tomoyo_parse_number_union(minor, &e.minor))
 799                 goto out;
 800         error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
 801                                      tomoyo_same_path_number3_acl,
 802                                      tomoyo_merge_path_number3_acl);
 803  out:
 804         tomoyo_put_name_union(&e.name);
 805         tomoyo_put_number_union(&e.mode);
 806         tomoyo_put_number_union(&e.major);
 807         tomoyo_put_number_union(&e.minor);
 808         return error;
 809 }
 810
 811 static bool tomoyo_same_path2_acl(const struct tomoyo_acl_info *a,
 812                                   const struct tomoyo_acl_info *b)
 813 {
 814         const struct tomoyo_path2_acl *p1 = container_of(a, typeof(*p1), head);
 815         const struct tomoyo_path2_acl *p2 = container_of(b, typeof(*p2), head);
 816         return tomoyo_is_same_acl_head(&p1->head, &p2->head)
 817                 && tomoyo_is_same_name_union(&p1->name1, &p2->name1)
 818                 && tomoyo_is_same_name_union(&p1->name2, &p2->name2);
 819 }
 820
 821 static bool tomoyo_merge_path2_acl(struct tomoyo_acl_info *a,
 822                                    struct tomoyo_acl_info *b,
 823                                    const bool is_delete)
 824 {
 825         u8 * const a_perm = &container_of(a, struct tomoyo_path2_acl, head)
 826                 ->perm;
 827         u8 perm = *a_perm;
 828         const u8 b_perm = container_of(b, struct tomoyo_path2_acl, head)->perm;
 829         if (is_delete)
 830                 perm &= ~b_perm;
 831         else
 832                 perm |= b_perm;
 833         *a_perm = perm;
 834         return !perm;
 835 }
 836
 837 /**
 838  * tomoyo_update_path2_acl - Update "struct tomoyo_path2_acl" list.
 839  *
 840  * @type:      Type of operation.
 841  * @filename1: First filename.
 842  * @filename2: Second filename.
 843  * @domain:    Pointer to "struct tomoyo_domain_info".
 844  * @is_delete: True if it is a delete request.
 845  *
 846  * Returns 0 on success, negative value otherwise.
 847  *
 848  * Caller holds tomoyo_read_lock().
 849  */
 850 static int tomoyo_update_path2_acl(const u8 type, const char *filename1,
 851                                    const char *filename2,
 852                                    struct tomoyo_domain_info * const domain,
 853                                    const bool is_delete)
 854 {
 855         struct tomoyo_path2_acl e = {
 856                 .head.type = TOMOYO_TYPE_PATH2_ACL,
 857                 .perm = 1 << type
 858         };
 859         int error = is_delete ? -ENOENT : -ENOMEM;
 860         if (!tomoyo_parse_name_union(filename1, &e.name1) ||
 861             !tomoyo_parse_name_union(filename2, &e.name2))
 862                 goto out;
 863         error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
 864                                      tomoyo_same_path2_acl,
 865                                      tomoyo_merge_path2_acl);
 866  out:
 867         tomoyo_put_name_union(&e.name1);
 868         tomoyo_put_name_union(&e.name2);
 869         return error;
 870 }
 871
 872 /**
 873  * tomoyo_path_number3_acl - Check permission for path/number/number/number operation.
 874  *
 875  * @r:        Pointer to "struct tomoyo_request_info".
 876  * @filename: Filename to check.
 877  * @perm:     Permission.
 878  * @mode:     Create mode.
 879  * @major:    Device major number.
 880  * @minor:    Device minor number.
 881  *
 882  * Returns 0 on success, -EPERM otherwise.
 883  *
 884  * Caller holds tomoyo_read_lock().
 885  */
 886 static int tomoyo_path_number3_acl(struct tomoyo_request_info *r,
 887                                    const struct tomoyo_path_info *filename,
 888                                    const u16 perm, const unsigned int mode,
 889                                    const unsigned int major,
 890                                    const unsigned int minor)
 891 {
 892         struct tomoyo_domain_info *domain = r->domain;
 893         struct tomoyo_acl_info *ptr;
 894         int error = -EPERM;
 895         list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
 896                 struct tomoyo_path_number3_acl *acl;
 897                 if (ptr->type != TOMOYO_TYPE_PATH_NUMBER3_ACL)
 898                         continue;
 899                 acl = container_of(ptr, struct tomoyo_path_number3_acl, head);
 900                 if (!tomoyo_compare_number_union(mode, &acl->mode))
 901                         continue;
 902                 if (!tomoyo_compare_number_union(major, &acl->major))
 903                         continue;
 904                 if (!tomoyo_compare_number_union(minor, &acl->minor))
 905                         continue;
 906                 if (!(acl->perm & perm))
 907                         continue;
 908                 if (!tomoyo_compare_name_union(filename, &acl->name))
 909                         continue;
 910                 error = 0;
 911                 break;
 912         }
 913         return error;
 914 }
 915
 916 /**
 917  * tomoyo_path2_acl - Check permission for double path operation.
 918  *
 919  * @r:         Pointer to "struct tomoyo_request_info".
 920  * @type:      Type of operation.
 921  * @filename1: First filename to check.
 922  * @filename2: Second filename to check.
 923  *
 924  * Returns 0 on success, -EPERM otherwise.
 925  *
 926  * Caller holds tomoyo_read_lock().
 927  */
 928 static int tomoyo_path2_acl(const struct tomoyo_request_info *r, const u8 type,
 929                             const struct tomoyo_path_info *filename1,
 930                             const struct tomoyo_path_info *filename2)
 931 {
 932         const struct tomoyo_domain_info *domain = r->domain;
 933         struct tomoyo_acl_info *ptr;
 934         const u8 perm = 1 << type;
 935         int error = -EPERM;
 936
 937         list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
 938                 struct tomoyo_path2_acl *acl;
 939                 if (ptr->type != TOMOYO_TYPE_PATH2_ACL)
 940                         continue;
 941                 acl = container_of(ptr, struct tomoyo_path2_acl, head);
 942                 if (!(acl->perm & perm))
 943                         continue;
 944                 if (!tomoyo_compare_name_union(filename1, &acl->name1))
 945                         continue;
 946                 if (!tomoyo_compare_name_union(filename2, &acl->name2))
 947                         continue;
 948                 error = 0;
 949                 break;
 950         }
 951         return error;
 952 }
 953
 954 /**
 955  * tomoyo_path_permission - Check permission for single path operation.
 956  *
 957  * @r:         Pointer to "struct tomoyo_request_info".
 958  * @operation: Type of operation.
 959  * @filename:  Filename to check.
 960  *
 961  * Returns 0 on success, negative value otherwise.
 962  *
 963  * Caller holds tomoyo_read_lock().
 964  */
 965 int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
 966                            const struct tomoyo_path_info *filename)
 967 {
 968         const char *msg;
 969         int error;
 970
 971  next:
 972         r->type = tomoyo_p2mac[operation];
 973         r->mode = tomoyo_get_mode(r->profile, r->type);
 974         if (r->mode == TOMOYO_CONFIG_DISABLED)
 975                 return 0;
 976         r->param_type = TOMOYO_TYPE_PATH_ACL;
 977         r->param.path.filename = filename;
 978         r->param.path.operation = operation;
 979         do {
 980                 error = tomoyo_path_acl(r, filename, 1 << operation);
 981                 if (error && operation == TOMOYO_TYPE_READ &&
 982                     !r->domain->ignore_global_allow_read &&
 983                     tomoyo_is_globally_readable_file(filename))
 984                         error = 0;
 985                 if (!error)
 986                         break;
 987                 msg = tomoyo_path2keyword(operation);
 988                 tomoyo_warn_log(r, "%s %s", msg, filename->name);
 989                 error = tomoyo_supervisor(r, "allow_%s %s\n", msg,
 990                                           tomoyo_file_pattern(filename));
 991                 /*
 992                  * Do not retry for execute request, for alias may have
 993                  * changed.
 994                  */
 995         } while (error == TOMOYO_RETRY_REQUEST &&
 996                  operation != TOMOYO_TYPE_EXECUTE);
 997         /*
 998          * Since "allow_truncate" doesn't imply "allow_rewrite" permission,
 999          * we need to check "allow_rewrite" permission if the filename is
1000          * specified by "deny_rewrite" keyword.
1001          */
1002         if (!error && operation == TOMOYO_TYPE_TRUNCATE &&
1003             tomoyo_is_no_rewrite_file(filename)) {
1004                 operation = TOMOYO_TYPE_REWRITE;
1005                 goto next;
1006         }
1007         return error;
1008 }
1009
1010 /**
1011  * tomoyo_path_number_acl - Check permission for ioctl/chmod/chown/chgrp operation.
1012  *
1013  * @r:        Pointer to "struct tomoyo_request_info".
1014  * @type:     Operation.
1015  * @filename: Filename to check.
1016  * @number:   Number.
1017  *
1018  * Returns 0 on success, -EPERM otherwise.
1019  *
1020  * Caller holds tomoyo_read_lock().
1021  */
1022 static int tomoyo_path_number_acl(struct tomoyo_request_info *r, const u8 type,
1023                                   const struct tomoyo_path_info *filename,
1024                                   const unsigned long number)
1025 {
1026         struct tomoyo_domain_info *domain = r->domain;
1027         struct tomoyo_acl_info *ptr;
1028         const u8 perm = 1 << type;
1029         int error = -EPERM;
1030         list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
1031                 struct tomoyo_path_number_acl *acl;
1032                 if (ptr->type != TOMOYO_TYPE_PATH_NUMBER_ACL)
1033                         continue;
1034                 acl = container_of(ptr, struct tomoyo_path_number_acl,
1035                                    head);
1036                 if (!(acl->perm & perm) ||
1037                     !tomoyo_compare_number_union(number, &acl->number) ||
1038                     !tomoyo_compare_name_union(filename, &acl->name))
1039                         continue;
1040                 error = 0;
1041                 break;
1042         }
1043         return error;
1044 }
1045
1046 static bool tomoyo_same_path_number_acl(const struct tomoyo_acl_info *a,
1047                                         const struct tomoyo_acl_info *b)
1048 {
1049         const struct tomoyo_path_number_acl *p1 = container_of(a, typeof(*p1),
1050                                                                head);
1051         const struct tomoyo_path_number_acl *p2 = container_of(b, typeof(*p2),
1052                                                                head);
1053         return tomoyo_is_same_acl_head(&p1->head, &p2->head)
1054                 && tomoyo_is_same_name_union(&p1->name, &p2->name)
1055                 && tomoyo_is_same_number_union(&p1->number, &p2->number);
1056 }
1057
1058 static bool tomoyo_merge_path_number_acl(struct tomoyo_acl_info *a,
1059                                          struct tomoyo_acl_info *b,
1060                                          const bool is_delete)
1061 {
1062         u8 * const a_perm = &container_of(a, struct tomoyo_path_number_acl,
1063                                           head)->perm;
1064         u8 perm = *a_perm;
1065         const u8 b_perm = container_of(b, struct tomoyo_path_number_acl, head)
1066                 ->perm;
1067         if (is_delete)
1068                 perm &= ~b_perm;
1069         else
1070                 perm |= b_perm;
1071         *a_perm = perm;
1072         return !perm;
1073 }
1074
1075 /**
1076  * tomoyo_update_path_number_acl - Update ioctl/chmod/chown/chgrp ACL.
1077  *
1078  * @type:      Type of operation.
1079  * @filename:  Filename.
1080  * @number:    Number.
1081  * @domain:    Pointer to "struct tomoyo_domain_info".
1082  * @is_delete: True if it is a delete request.
1083  *
1084  * Returns 0 on success, negative value otherwise.
1085  */
1086 static int tomoyo_update_path_number_acl(const u8 type, const char *filename,
1087                                          char *number,
1088                                          struct tomoyo_domain_info * const
1089                                          domain,
1090                                          const bool is_delete)
1091 {
1092         struct tomoyo_path_number_acl e = {
1093                 .head.type = TOMOYO_TYPE_PATH_NUMBER_ACL,
1094                 .perm = 1 << type
1095         };
1096         int error = is_delete ? -ENOENT : -ENOMEM;
1097         if (!tomoyo_parse_name_union(filename, &e.name))
1098                 return -EINVAL;
1099         if (!tomoyo_parse_number_union(number, &e.number))
1100                 goto out;
1101         error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
1102                                      tomoyo_same_path_number_acl,
1103                                      tomoyo_merge_path_number_acl);
1104  out:
1105         tomoyo_put_name_union(&e.name);
1106         tomoyo_put_number_union(&e.number);
1107         return error;
1108 }
1109
1110 /**
1111  * tomoyo_path_number_perm2 - Check permission for "create", "mkdir", "mkfifo", "mksock", "ioctl", "chmod", "chown", "chgrp".
1112  *
1113  * @r:        Pointer to "strct tomoyo_request_info".
1114  * @filename: Filename to check.
1115  * @number:   Number.
1116  *
1117  * Returns 0 on success, negative value otherwise.
1118  *
1119  * Caller holds tomoyo_read_lock().
1120  */
1121 static int tomoyo_path_number_perm2(struct tomoyo_request_info *r,
1122                                     const u8 type,
1123                                     const struct tomoyo_path_info *filename,
1124                                     const unsigned long number)
1125 {
1126         char buffer[64];
1127         int error;
1128         u8 radix;
1129         const char *msg;
1130
1131         if (!filename)
1132                 return 0;
1133         switch (type) {
1134         case TOMOYO_TYPE_CREATE:
1135         case TOMOYO_TYPE_MKDIR:
1136         case TOMOYO_TYPE_MKFIFO:
1137         case TOMOYO_TYPE_MKSOCK:
1138         case TOMOYO_TYPE_CHMOD:
1139                 radix = TOMOYO_VALUE_TYPE_OCTAL;
1140                 break;
1141         case TOMOYO_TYPE_IOCTL:
1142                 radix = TOMOYO_VALUE_TYPE_HEXADECIMAL;
1143                 break;
1144         default:
1145                 radix = TOMOYO_VALUE_TYPE_DECIMAL;
1146                 break;
1147         }
1148         tomoyo_print_ulong(buffer, sizeof(buffer), number, radix);
1149         r->param_type = TOMOYO_TYPE_PATH_NUMBER_ACL;
1150         r->param.path_number.operation = type;
1151         r->param.path_number.filename = filename;
1152         r->param.path_number.number = number;
1153         do {
1154                 error = tomoyo_path_number_acl(r, type, filename, number);
1155                 if (!error)
1156                         break;
1157                 msg = tomoyo_path_number2keyword(type);
1158                 tomoyo_warn_log(r, "%s %s %s", msg, filename->name, buffer);
1159                 error = tomoyo_supervisor(r, "allow_%s %s %s\n", msg,
1160                                           tomoyo_file_pattern(filename),
1161                                           buffer);
1162         } while (error == TOMOYO_RETRY_REQUEST);
1163         return error;
1164 }
1165
1166 /**
1167  * tomoyo_path_number_perm - Check permission for "create", "mkdir", "mkfifo", "mksock", "ioctl", "chmod", "chown", "chgrp".
1168  *
1169  * @type:   Type of operation.
1170  * @path:   Pointer to "struct path".
1171  * @number: Number.
1172  *
1173  * Returns 0 on success, negative value otherwise.
1174  */
1175 int tomoyo_path_number_perm(const u8 type, struct path *path,
1176                             unsigned long number)
1177 {
1178         struct tomoyo_request_info r;
1179         int error = -ENOMEM;
1180         struct tomoyo_path_info buf;
1181         int idx;
1182
1183         if (tomoyo_init_request_info(&r, NULL, tomoyo_pn2mac[type])
1184             == TOMOYO_CONFIG_DISABLED || !path->mnt || !path->dentry)
1185                 return 0;
1186         idx = tomoyo_read_lock();
1187         if (!tomoyo_get_realpath(&buf, path))
1188                 goto out;
1189         if (type == TOMOYO_TYPE_MKDIR)
1190                 tomoyo_add_slash(&buf);
1191         error = tomoyo_path_number_perm2(&r, type, &buf, number);
1192  out:
1193         kfree(buf.name);
1194         tomoyo_read_unlock(idx);
1195         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1196                 error = 0;
1197         return error;
1198 }
1199
1200 /**
1201  * tomoyo_check_open_permission - Check permission for "read" and "write".
1202  *
1203  * @domain: Pointer to "struct tomoyo_domain_info".
1204  * @path:   Pointer to "struct path".
1205  * @flag:   Flags for open().
1206  *
1207  * Returns 0 on success, negative value otherwise.
1208  */
1209 int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
1210                                  struct path *path, const int flag)
1211 {
1212         const u8 acc_mode = ACC_MODE(flag);
1213         int error = -ENOMEM;
1214         struct tomoyo_path_info buf;
1215         struct tomoyo_request_info r;
1216         int idx;
1217
1218         if (!path->mnt ||
1219             (path->dentry->d_inode && S_ISDIR(path->dentry->d_inode->i_mode)))
1220                 return 0;
1221         buf.name = NULL;
1222         r.mode = TOMOYO_CONFIG_DISABLED;
1223         idx = tomoyo_read_lock();
1224         if (!tomoyo_get_realpath(&buf, path))
1225                 goto out;
1226         error = 0;
1227         /*
1228          * If the filename is specified by "deny_rewrite" keyword,
1229          * we need to check "allow_rewrite" permission when the filename is not
1230          * opened for append mode or the filename is truncated at open time.
1231          */
1232         if ((acc_mode & MAY_WRITE) && !(flag & O_APPEND)
1233             && tomoyo_init_request_info(&r, domain, TOMOYO_MAC_FILE_REWRITE)
1234             != TOMOYO_CONFIG_DISABLED) {
1235                 if (!tomoyo_get_realpath(&buf, path)) {
1236                         error = -ENOMEM;
1237                         goto out;
1238                 }
1239                 if (tomoyo_is_no_rewrite_file(&buf))
1240                         error = tomoyo_path_permission(&r, TOMOYO_TYPE_REWRITE,
1241                                                        &buf);
1242         }
1243         if (!error && acc_mode &&
1244             tomoyo_init_request_info(&r, domain, TOMOYO_MAC_FILE_OPEN)
1245             != TOMOYO_CONFIG_DISABLED) {
1246                 u8 operation;
1247                 if (!buf.name && !tomoyo_get_realpath(&buf, path)) {
1248                         error = -ENOMEM;
1249                         goto out;
1250                 }
1251                 if (acc_mode == (MAY_READ | MAY_WRITE))
1252                         operation = TOMOYO_TYPE_READ_WRITE;
1253                 else if (acc_mode == MAY_READ)
1254                         operation = TOMOYO_TYPE_READ;
1255                 else
1256                         operation = TOMOYO_TYPE_WRITE;
1257                 error = tomoyo_path_permission(&r, operation, &buf);
1258         }
1259  out:
1260         kfree(buf.name);
1261         tomoyo_read_unlock(idx);
1262         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1263                 error = 0;
1264         return error;
1265 }
1266
1267 /**
1268  * tomoyo_path_perm - Check permission for "unlink", "rmdir", "truncate", "symlink", "rewrite", "chroot" and "unmount".
1269  *
1270  * @operation: Type of operation.
1271  * @path:      Pointer to "struct path".
1272  *
1273  * Returns 0 on success, negative value otherwise.
1274  */
1275 int tomoyo_path_perm(const u8 operation, struct path *path)
1276 {
1277         int error = -ENOMEM;
1278         struct tomoyo_path_info buf;
1279         struct tomoyo_request_info r;
1280         int idx;
1281
1282         if (!path->mnt)
1283                 return 0;
1284         if (tomoyo_init_request_info(&r, NULL, tomoyo_p2mac[operation])
1285             == TOMOYO_CONFIG_DISABLED)
1286                 return 0;
1287         buf.name = NULL;
1288         idx = tomoyo_read_lock();
1289         if (!tomoyo_get_realpath(&buf, path))
1290                 goto out;
1291         switch (operation) {
1292         case TOMOYO_TYPE_REWRITE:
1293                 if (!tomoyo_is_no_rewrite_file(&buf)) {
1294                         error = 0;
1295                         goto out;
1296                 }
1297                 break;
1298         case TOMOYO_TYPE_RMDIR:
1299         case TOMOYO_TYPE_CHROOT:
1300         case TOMOYO_TYPE_UMOUNT:
1301                 tomoyo_add_slash(&buf);
1302                 break;
1303         }
1304         error = tomoyo_path_permission(&r, operation, &buf);
1305  out:
1306         kfree(buf.name);
1307         tomoyo_read_unlock(idx);
1308         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1309                 error = 0;
1310         return error;
1311 }
1312
1313 /**
1314  * tomoyo_path_number3_perm2 - Check permission for path/number/number/number operation.
1315  *
1316  * @r:         Pointer to "struct tomoyo_request_info".
1317  * @operation: Type of operation.
1318  * @filename:  Filename to check.
1319  * @mode:      Create mode.
1320  * @dev:       Device number.
1321  *
1322  * Returns 0 on success, negative value otherwise.
1323  *
1324  * Caller holds tomoyo_read_lock().
1325  */
1326 static int tomoyo_path_number3_perm2(struct tomoyo_request_info *r,
1327                                      const u8 operation,
1328                                      const struct tomoyo_path_info *filename,
1329                                      const unsigned int mode,
1330                                      const unsigned int dev)
1331 {
1332         int error;
1333         const char *msg;
1334         const unsigned int major = MAJOR(dev);
1335         const unsigned int minor = MINOR(dev);
1336
1337         do {
1338                 error = tomoyo_path_number3_acl(r, filename, 1 << operation,
1339                                                 mode, major, minor);
1340                 if (!error)
1341                         break;
1342                 msg = tomoyo_path_number32keyword(operation);
1343                 tomoyo_warn_log(r, "%s %s 0%o %u %u", msg, filename->name,
1344                                 mode, major, minor);
1345                 error = tomoyo_supervisor(r, "allow_%s %s 0%o %u %u\n", msg,
1346                                           tomoyo_file_pattern(filename), mode,
1347                                           major, minor);
1348         } while (error == TOMOYO_RETRY_REQUEST);
1349         if (r->mode != TOMOYO_CONFIG_ENFORCING)
1350                 error = 0;
1351         return error;
1352 }
1353
1354 /**
1355  * tomoyo_path_number3_perm - Check permission for "mkblock" and "mkchar".
1356  *
1357  * @operation: Type of operation. (TOMOYO_TYPE_MKCHAR or TOMOYO_TYPE_MKBLOCK)
1358  * @path:      Pointer to "struct path".
1359  * @mode:      Create mode.
1360  * @dev:       Device number.
1361  *
1362  * Returns 0 on success, negative value otherwise.
1363  */
1364 int tomoyo_path_number3_perm(const u8 operation, struct path *path,
1365                              const unsigned int mode, unsigned int dev)
1366 {
1367         struct tomoyo_request_info r;
1368         int error = -ENOMEM;
1369         struct tomoyo_path_info buf;
1370         int idx;
1371
1372         if (!path->mnt ||
1373             tomoyo_init_request_info(&r, NULL, tomoyo_pnnn2mac[operation])
1374             == TOMOYO_CONFIG_DISABLED)
1375                 return 0;
1376         idx = tomoyo_read_lock();
1377         error = -ENOMEM;
1378         if (tomoyo_get_realpath(&buf, path)) {
1379                 dev = new_decode_dev(dev);
1380                 r.param_type = TOMOYO_TYPE_PATH_NUMBER3_ACL;
1381                 r.param.mkdev.filename = &buf;
1382                 r.param.mkdev.operation = operation;
1383                 r.param.mkdev.mode = mode;
1384                 r.param.mkdev.major = MAJOR(dev);
1385                 r.param.mkdev.minor = MINOR(dev);
1386                 error = tomoyo_path_number3_perm2(&r, operation, &buf, mode,
1387                                                   dev);
1388                 kfree(buf.name);
1389         }
1390         tomoyo_read_unlock(idx);
1391         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1392                 error = 0;
1393         return error;
1394 }
1395
1396 /**
1397  * tomoyo_path2_perm - Check permission for "rename", "link" and "pivot_root".
1398  *
1399  * @operation: Type of operation.
1400  * @path1:      Pointer to "struct path".
1401  * @path2:      Pointer to "struct path".
1402  *
1403  * Returns 0 on success, negative value otherwise.
1404  */
1405 int tomoyo_path2_perm(const u8 operation, struct path *path1,
1406                       struct path *path2)
1407 {
1408         int error = -ENOMEM;
1409         const char *msg;
1410         struct tomoyo_path_info buf1;
1411         struct tomoyo_path_info buf2;
1412         struct tomoyo_request_info r;
1413         int idx;
1414
1415         if (!path1->mnt || !path2->mnt ||
1416             tomoyo_init_request_info(&r, NULL, tomoyo_pp2mac[operation])
1417             == TOMOYO_CONFIG_DISABLED)
1418                 return 0;
1419         buf1.name = NULL;
1420         buf2.name = NULL;
1421         idx = tomoyo_read_lock();
1422         if (!tomoyo_get_realpath(&buf1, path1) ||
1423             !tomoyo_get_realpath(&buf2, path2))
1424                 goto out;
1425         switch (operation) {
1426                 struct dentry *dentry;
1427         case TOMOYO_TYPE_RENAME:
1428         case TOMOYO_TYPE_LINK:
1429                 dentry = path1->dentry;
1430                 if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
1431                         break;
1432                 /* fall through */
1433         case TOMOYO_TYPE_PIVOT_ROOT:
1434                 tomoyo_add_slash(&buf1);
1435                 tomoyo_add_slash(&buf2);
1436                 break;
1437         }
1438         r.param_type = TOMOYO_TYPE_PATH2_ACL;
1439         r.param.path2.operation = operation;
1440         r.param.path2.filename1 = &buf1;
1441         r.param.path2.filename2 = &buf2;
1442         do {
1443                 error = tomoyo_path2_acl(&r, operation, &buf1, &buf2);
1444                 if (!error)
1445                         break;
1446                 msg = tomoyo_path22keyword(operation);
1447                 tomoyo_warn_log(&r, "%s %s %s", msg, buf1.name, buf2.name);
1448                 error = tomoyo_supervisor(&r, "allow_%s %s %s\n", msg,
1449                                           tomoyo_file_pattern(&buf1),
1450                                           tomoyo_file_pattern(&buf2));
1451         } while (error == TOMOYO_RETRY_REQUEST);
1452  out:
1453         kfree(buf1.name);
1454         kfree(buf2.name);
1455         tomoyo_read_unlock(idx);
1456         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1457                 error = 0;
1458         return error;
1459 }
1460
1461 /**
1462  * tomoyo_write_file_policy - Update file related list.
1463  *
1464  * @data:      String to parse.
1465  * @domain:    Pointer to "struct tomoyo_domain_info".
1466  * @is_delete: True if it is a delete request.
1467  *
1468  * Returns 0 on success, negative value otherwise.
1469  *
1470  * Caller holds tomoyo_read_lock().
1471  */
1472 int tomoyo_write_file_policy(char *data, struct tomoyo_domain_info *domain,
1473                              const bool is_delete)
1474 {
1475         char *w[5];
1476         u8 type;
1477         if (!tomoyo_tokenize(data, w, sizeof(w)) || !w[1][0])
1478                 return -EINVAL;
1479         if (strncmp(w[0], "allow_", 6))
1480                 goto out;
1481         w[0] += 6;
1482         for (type = 0; type < TOMOYO_MAX_PATH_OPERATION; type++) {
1483                 if (strcmp(w[0], tomoyo_path_keyword[type]))
1484                         continue;
1485                 return tomoyo_update_path_acl(type, w[1], domain, is_delete);
1486         }
1487         if (!w[2][0])
1488                 goto out;
1489         for (type = 0; type < TOMOYO_MAX_PATH2_OPERATION; type++) {
1490                 if (strcmp(w[0], tomoyo_path2_keyword[type]))
1491                         continue;
1492                 return tomoyo_update_path2_acl(type, w[1], w[2], domain,
1493                                                is_delete);
1494         }
1495         for (type = 0; type < TOMOYO_MAX_PATH_NUMBER_OPERATION; type++) {
1496                 if (strcmp(w[0], tomoyo_path_number_keyword[type]))
1497                         continue;
1498                 return tomoyo_update_path_number_acl(type, w[1], w[2], domain,
1499                                                      is_delete);
1500         }
1501         if (!w[3][0] || !w[4][0])
1502                 goto out;
1503         for (type = 0; type < TOMOYO_MAX_PATH_NUMBER3_OPERATION; type++) {
1504                 if (strcmp(w[0], tomoyo_path_number3_keyword[type]))
1505                         continue;
1506                 return tomoyo_update_path_number3_acl(type, w[1], w[2], w[3],
1507                                                       w[4], domain, is_delete);
1508         }
1509  out:
1510         return -EINVAL;
1511 }