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 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 const char *tomoyo_mkdev_keyword[TOMOYO_MAX_MKDEV_OPERATION] = {
  29         [TOMOYO_TYPE_MKBLOCK]    = "mkblock",
  30         [TOMOYO_TYPE_MKCHAR]     = "mkchar",
  31 };
  32
  33 /* Keyword array for operations with two pathnames. */
  34 const char *tomoyo_path2_keyword[TOMOYO_MAX_PATH2_OPERATION] = {
  35         [TOMOYO_TYPE_LINK]       = "link",
  36         [TOMOYO_TYPE_RENAME]     = "rename",
  37         [TOMOYO_TYPE_PIVOT_ROOT] = "pivot_root",
  38 };
  39
  40 /* Keyword array for operations with one pathname and one number. */
  41 const char *tomoyo_path_number_keyword[TOMOYO_MAX_PATH_NUMBER_OPERATION] = {
  42         [TOMOYO_TYPE_CREATE]     = "create",
  43         [TOMOYO_TYPE_MKDIR]      = "mkdir",
  44         [TOMOYO_TYPE_MKFIFO]     = "mkfifo",
  45         [TOMOYO_TYPE_MKSOCK]     = "mksock",
  46         [TOMOYO_TYPE_IOCTL]      = "ioctl",
  47         [TOMOYO_TYPE_CHMOD]      = "chmod",
  48         [TOMOYO_TYPE_CHOWN]      = "chown",
  49         [TOMOYO_TYPE_CHGRP]      = "chgrp",
  50 };
  51
  52 static const u8 tomoyo_p2mac[TOMOYO_MAX_PATH_OPERATION] = {
  53         [TOMOYO_TYPE_READ_WRITE] = TOMOYO_MAC_FILE_OPEN,
  54         [TOMOYO_TYPE_EXECUTE]    = TOMOYO_MAC_FILE_EXECUTE,
  55         [TOMOYO_TYPE_READ]       = TOMOYO_MAC_FILE_OPEN,
  56         [TOMOYO_TYPE_WRITE]      = TOMOYO_MAC_FILE_OPEN,
  57         [TOMOYO_TYPE_UNLINK]     = TOMOYO_MAC_FILE_UNLINK,
  58         [TOMOYO_TYPE_RMDIR]      = TOMOYO_MAC_FILE_RMDIR,
  59         [TOMOYO_TYPE_TRUNCATE]   = TOMOYO_MAC_FILE_TRUNCATE,
  60         [TOMOYO_TYPE_SYMLINK]    = TOMOYO_MAC_FILE_SYMLINK,
  61         [TOMOYO_TYPE_REWRITE]    = TOMOYO_MAC_FILE_REWRITE,
  62         [TOMOYO_TYPE_CHROOT]     = TOMOYO_MAC_FILE_CHROOT,
  63         [TOMOYO_TYPE_UMOUNT]     = TOMOYO_MAC_FILE_UMOUNT,
  64 };
  65
  66 static const u8 tomoyo_pnnn2mac[TOMOYO_MAX_MKDEV_OPERATION] = {
  67         [TOMOYO_TYPE_MKBLOCK] = TOMOYO_MAC_FILE_MKBLOCK,
  68         [TOMOYO_TYPE_MKCHAR]  = TOMOYO_MAC_FILE_MKCHAR,
  69 };
  70
  71 static const u8 tomoyo_pp2mac[TOMOYO_MAX_PATH2_OPERATION] = {
  72         [TOMOYO_TYPE_LINK]       = TOMOYO_MAC_FILE_LINK,
  73         [TOMOYO_TYPE_RENAME]     = TOMOYO_MAC_FILE_RENAME,
  74         [TOMOYO_TYPE_PIVOT_ROOT] = TOMOYO_MAC_FILE_PIVOT_ROOT,
  75 };
  76
  77 static const u8 tomoyo_pn2mac[TOMOYO_MAX_PATH_NUMBER_OPERATION] = {
  78         [TOMOYO_TYPE_CREATE] = TOMOYO_MAC_FILE_CREATE,
  79         [TOMOYO_TYPE_MKDIR]  = TOMOYO_MAC_FILE_MKDIR,
  80         [TOMOYO_TYPE_MKFIFO] = TOMOYO_MAC_FILE_MKFIFO,
  81         [TOMOYO_TYPE_MKSOCK] = TOMOYO_MAC_FILE_MKSOCK,
  82         [TOMOYO_TYPE_IOCTL]  = TOMOYO_MAC_FILE_IOCTL,
  83         [TOMOYO_TYPE_CHMOD]  = TOMOYO_MAC_FILE_CHMOD,
  84         [TOMOYO_TYPE_CHOWN]  = TOMOYO_MAC_FILE_CHOWN,
  85         [TOMOYO_TYPE_CHGRP]  = TOMOYO_MAC_FILE_CHGRP,
  86 };
  87
  88 void tomoyo_put_name_union(struct tomoyo_name_union *ptr)
  89 {
  90         if (!ptr)
  91                 return;
  92         if (ptr->is_group)
  93                 tomoyo_put_group(ptr->group);
  94         else
  95                 tomoyo_put_name(ptr->filename);
  96 }
  97
  98 bool tomoyo_compare_name_union(const struct tomoyo_path_info *name,
  99                                const struct tomoyo_name_union *ptr)
 100 {
 101         if (ptr->is_group)
 102                 return tomoyo_path_matches_group(name, ptr->group);
 103         return tomoyo_path_matches_pattern(name, ptr->filename);
 104 }
 105
 106 void tomoyo_put_number_union(struct tomoyo_number_union *ptr)
 107 {
 108         if (ptr && ptr->is_group)
 109                 tomoyo_put_group(ptr->group);
 110 }
 111
 112 bool tomoyo_compare_number_union(const unsigned long value,
 113                                  const struct tomoyo_number_union *ptr)
 114 {
 115         if (ptr->is_group)
 116                 return tomoyo_number_matches_group(value, value, ptr->group);
 117         return value >= ptr->values[0] && value <= ptr->values[1];
 118 }
 119
 120 static void tomoyo_add_slash(struct tomoyo_path_info *buf)
 121 {
 122         if (buf->is_dir)
 123                 return;
 124         /*
 125          * This is OK because tomoyo_encode() reserves space for appending "/".
 126          */
 127         strcat((char *) buf->name, "/");
 128         tomoyo_fill_path_info(buf);
 129 }
 130
 131 /**
 132  * tomoyo_strendswith - Check whether the token ends with the given token.
 133  *
 134  * @name: The token to check.
 135  * @tail: The token to find.
 136  *
 137  * Returns true if @name ends with @tail, false otherwise.
 138  */
 139 static bool tomoyo_strendswith(const char *name, const char *tail)
 140 {
 141         int len;
 142
 143         if (!name || !tail)
 144                 return false;
 145         len = strlen(name) - strlen(tail);
 146         return len >= 0 && !strcmp(name + len, tail);
 147 }
 148
 149 /**
 150  * tomoyo_get_realpath - Get realpath.
 151  *
 152  * @buf:  Pointer to "struct tomoyo_path_info".
 153  * @path: Pointer to "struct path".
 154  *
 155  * Returns true on success, false otherwise.
 156  */
 157 static bool tomoyo_get_realpath(struct tomoyo_path_info *buf, struct path *path)
 158 {
 159         buf->name = tomoyo_realpath_from_path(path);
 160         if (buf->name) {
 161                 tomoyo_fill_path_info(buf);
 162                 return true;
 163         }
 164         return false;
 165 }
 166
 167 /**
 168  * tomoyo_audit_path_log - Audit path request log.
 169  *
 170  * @r: Pointer to "struct tomoyo_request_info".
 171  *
 172  * Returns 0 on success, negative value otherwise.
 173  */
 174 static int tomoyo_audit_path_log(struct tomoyo_request_info *r)
 175 {
 176         const char *operation = tomoyo_path_keyword[r->param.path.operation];
 177         const struct tomoyo_path_info *filename = r->param.path.filename;
 178         if (r->granted)
 179                 return 0;
 180         tomoyo_warn_log(r, "%s %s", operation, filename->name);
 181         return tomoyo_supervisor(r, "allow_%s %s\n", operation,
 182                                  tomoyo_file_pattern(filename));
 183 }
 184
 185 /**
 186  * tomoyo_audit_path2_log - Audit path/path request log.
 187  *
 188  * @r: Pointer to "struct tomoyo_request_info".
 189  *
 190  * Returns 0 on success, negative value otherwise.
 191  */
 192 static int tomoyo_audit_path2_log(struct tomoyo_request_info *r)
 193 {
 194         const char *operation = tomoyo_path2_keyword[r->param.path2.operation];
 195         const struct tomoyo_path_info *filename1 = r->param.path2.filename1;
 196         const struct tomoyo_path_info *filename2 = r->param.path2.filename2;
 197         if (r->granted)
 198                 return 0;
 199         tomoyo_warn_log(r, "%s %s %s", operation, filename1->name,
 200                         filename2->name);
 201         return tomoyo_supervisor(r, "allow_%s %s %s\n", operation,
 202                                  tomoyo_file_pattern(filename1),
 203                                  tomoyo_file_pattern(filename2));
 204 }
 205
 206 /**
 207  * tomoyo_audit_mkdev_log - Audit path/number/number/number request log.
 208  *
 209  * @r: Pointer to "struct tomoyo_request_info".
 210  *
 211  * Returns 0 on success, negative value otherwise.
 212  */
 213 static int tomoyo_audit_mkdev_log(struct tomoyo_request_info *r)
 214 {
 215         const char *operation = tomoyo_mkdev_keyword[r->param.mkdev.operation];
 216         const struct tomoyo_path_info *filename = r->param.mkdev.filename;
 217         const unsigned int major = r->param.mkdev.major;
 218         const unsigned int minor = r->param.mkdev.minor;
 219         const unsigned int mode = r->param.mkdev.mode;
 220         if (r->granted)
 221                 return 0;
 222         tomoyo_warn_log(r, "%s %s 0%o %u %u", operation, filename->name, mode,
 223                         major, minor);
 224         return tomoyo_supervisor(r, "allow_%s %s 0%o %u %u\n", operation,
 225                                  tomoyo_file_pattern(filename), mode, major,
 226                                  minor);
 227 }
 228
 229 /**
 230  * tomoyo_audit_path_number_log - Audit path/number request log.
 231  *
 232  * @r:     Pointer to "struct tomoyo_request_info".
 233  * @error: Error code.
 234  *
 235  * Returns 0 on success, negative value otherwise.
 236  */
 237 static int tomoyo_audit_path_number_log(struct tomoyo_request_info *r)
 238 {
 239         const u8 type = r->param.path_number.operation;
 240         u8 radix;
 241         const struct tomoyo_path_info *filename = r->param.path_number.filename;
 242         const char *operation = tomoyo_path_number_keyword[type];
 243         char buffer[64];
 244         if (r->granted)
 245                 return 0;
 246         switch (type) {
 247         case TOMOYO_TYPE_CREATE:
 248         case TOMOYO_TYPE_MKDIR:
 249         case TOMOYO_TYPE_MKFIFO:
 250         case TOMOYO_TYPE_MKSOCK:
 251         case TOMOYO_TYPE_CHMOD:
 252                 radix = TOMOYO_VALUE_TYPE_OCTAL;
 253                 break;
 254         case TOMOYO_TYPE_IOCTL:
 255                 radix = TOMOYO_VALUE_TYPE_HEXADECIMAL;
 256                 break;
 257         default:
 258                 radix = TOMOYO_VALUE_TYPE_DECIMAL;
 259                 break;
 260         }
 261         tomoyo_print_ulong(buffer, sizeof(buffer), r->param.path_number.number,
 262                            radix);
 263         tomoyo_warn_log(r, "%s %s %s", operation, filename->name, buffer);
 264         return tomoyo_supervisor(r, "allow_%s %s %s\n", operation,
 265                                  tomoyo_file_pattern(filename), buffer);
 266 }
 267
 268 static bool tomoyo_same_globally_readable(const struct tomoyo_acl_head *a,
 269                                           const struct tomoyo_acl_head *b)
 270 {
 271         return container_of(a, struct tomoyo_globally_readable_file_entry,
 272                             head)->filename ==
 273                 container_of(b, struct tomoyo_globally_readable_file_entry,
 274                              head)->filename;
 275 }
 276
 277 /**
 278  * tomoyo_update_globally_readable_entry - Update "struct tomoyo_globally_readable_file_entry" list.
 279  *
 280  * @filename:  Filename unconditionally permitted to open() for reading.
 281  * @is_delete: True if it is a delete request.
 282  *
 283  * Returns 0 on success, negative value otherwise.
 284  *
 285  * Caller holds tomoyo_read_lock().
 286  */
 287 static int tomoyo_update_globally_readable_entry(const char *filename,
 288                                                  const bool is_delete)
 289 {
 290         struct tomoyo_globally_readable_file_entry e = { };
 291         int error;
 292
 293         if (!tomoyo_correct_word(filename))
 294                 return -EINVAL;
 295         e.filename = tomoyo_get_name(filename);
 296         if (!e.filename)
 297                 return -ENOMEM;
 298         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
 299                                      &tomoyo_policy_list
 300                                      [TOMOYO_ID_GLOBALLY_READABLE],
 301                                      tomoyo_same_globally_readable);
 302         tomoyo_put_name(e.filename);
 303         return error;
 304 }
 305
 306 /**
 307  * tomoyo_globally_readable_file - Check if the file is unconditionnaly permitted to be open()ed for reading.
 308  *
 309  * @filename: The filename to check.
 310  *
 311  * Returns true if any domain can open @filename for reading, false otherwise.
 312  *
 313  * Caller holds tomoyo_read_lock().
 314  */
 315 static bool tomoyo_globally_readable_file(const struct tomoyo_path_info *
 316                                              filename)
 317 {
 318         struct tomoyo_globally_readable_file_entry *ptr;
 319         bool found = false;
 320
 321         list_for_each_entry_rcu(ptr, &tomoyo_policy_list
 322                                 [TOMOYO_ID_GLOBALLY_READABLE], head.list) {
 323                 if (!ptr->head.is_deleted &&
 324                     tomoyo_path_matches_pattern(filename, ptr->filename)) {
 325                         found = true;
 326                         break;
 327                 }
 328         }
 329         return found;
 330 }
 331
 332 /**
 333  * tomoyo_write_globally_readable_policy - Write "struct tomoyo_globally_readable_file_entry" list.
 334  *
 335  * @data:      String to parse.
 336  * @is_delete: True if it is a delete request.
 337  *
 338  * Returns 0 on success, negative value otherwise.
 339  *
 340  * Caller holds tomoyo_read_lock().
 341  */
 342 int tomoyo_write_globally_readable_policy(char *data, const bool is_delete)
 343 {
 344         return tomoyo_update_globally_readable_entry(data, is_delete);
 345 }
 346
 347 /**
 348  * tomoyo_read_globally_readable_policy - Read "struct tomoyo_globally_readable_file_entry" list.
 349  *
 350  * @head: Pointer to "struct tomoyo_io_buffer".
 351  *
 352  * Returns true on success, false otherwise.
 353  *
 354  * Caller holds tomoyo_read_lock().
 355  */
 356 bool tomoyo_read_globally_readable_policy(struct tomoyo_io_buffer *head)
 357 {
 358         struct list_head *pos;
 359         bool done = true;
 360
 361         list_for_each_cookie(pos, head->read_var2,
 362                              &tomoyo_policy_list[TOMOYO_ID_GLOBALLY_READABLE]) {
 363                 struct tomoyo_globally_readable_file_entry *ptr;
 364                 ptr = list_entry(pos,
 365                                  struct tomoyo_globally_readable_file_entry,
 366                                  head.list);
 367                 if (ptr->head.is_deleted)
 368                         continue;
 369                 done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_READ "%s\n",
 370                                         ptr->filename->name);
 371                 if (!done)
 372                         break;
 373         }
 374         return done;
 375 }
 376
 377 static bool tomoyo_same_pattern(const struct tomoyo_acl_head *a,
 378                                 const struct tomoyo_acl_head *b)
 379 {
 380         return container_of(a, struct tomoyo_pattern_entry, head)->pattern ==
 381                 container_of(b, struct tomoyo_pattern_entry, head)->pattern;
 382 }
 383
 384 /**
 385  * tomoyo_update_file_pattern_entry - Update "struct tomoyo_pattern_entry" list.
 386  *
 387  * @pattern:   Pathname pattern.
 388  * @is_delete: True if it is a delete request.
 389  *
 390  * Returns 0 on success, negative value otherwise.
 391  *
 392  * Caller holds tomoyo_read_lock().
 393  */
 394 static int tomoyo_update_file_pattern_entry(const char *pattern,
 395                                             const bool is_delete)
 396 {
 397         struct tomoyo_pattern_entry e = { };
 398         int error;
 399
 400         if (!tomoyo_correct_word(pattern))
 401                 return -EINVAL;
 402         e.pattern = tomoyo_get_name(pattern);
 403         if (!e.pattern)
 404                 return -ENOMEM;
 405         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
 406                                      &tomoyo_policy_list[TOMOYO_ID_PATTERN],
 407                                      tomoyo_same_pattern);
 408         tomoyo_put_name(e.pattern);
 409         return error;
 410 }
 411
 412 /**
 413  * tomoyo_file_pattern - Get patterned pathname.
 414  *
 415  * @filename: The filename to find patterned pathname.
 416  *
 417  * Returns pointer to pathname pattern if matched, @filename otherwise.
 418  *
 419  * Caller holds tomoyo_read_lock().
 420  */
 421 const char *tomoyo_file_pattern(const struct tomoyo_path_info *filename)
 422 {
 423         struct tomoyo_pattern_entry *ptr;
 424         const struct tomoyo_path_info *pattern = NULL;
 425
 426         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_PATTERN],
 427                                 head.list) {
 428                 if (ptr->head.is_deleted)
 429                         continue;
 430                 if (!tomoyo_path_matches_pattern(filename, ptr->pattern))
 431                         continue;
 432                 pattern = ptr->pattern;
 433                 if (tomoyo_strendswith(pattern->name, "/\\*")) {
 434                         /* Do nothing. Try to find the better match. */
 435                 } else {
 436                         /* This would be the better match. Use this. */
 437                         break;
 438                 }
 439         }
 440         if (pattern)
 441                 filename = pattern;
 442         return filename->name;
 443 }
 444
 445 /**
 446  * tomoyo_write_pattern_policy - Write "struct tomoyo_pattern_entry" list.
 447  *
 448  * @data:      String to parse.
 449  * @is_delete: True if it is a delete request.
 450  *
 451  * Returns 0 on success, negative value otherwise.
 452  *
 453  * Caller holds tomoyo_read_lock().
 454  */
 455 int tomoyo_write_pattern_policy(char *data, const bool is_delete)
 456 {
 457         return tomoyo_update_file_pattern_entry(data, is_delete);
 458 }
 459
 460 /**
 461  * tomoyo_read_file_pattern - Read "struct tomoyo_pattern_entry" list.
 462  *
 463  * @head: Pointer to "struct tomoyo_io_buffer".
 464  *
 465  * Returns true on success, false otherwise.
 466  *
 467  * Caller holds tomoyo_read_lock().
 468  */
 469 bool tomoyo_read_file_pattern(struct tomoyo_io_buffer *head)
 470 {
 471         struct list_head *pos;
 472         bool done = true;
 473
 474         list_for_each_cookie(pos, head->read_var2,
 475                              &tomoyo_policy_list[TOMOYO_ID_PATTERN]) {
 476                 struct tomoyo_pattern_entry *ptr;
 477                 ptr = list_entry(pos, struct tomoyo_pattern_entry, head.list);
 478                 if (ptr->head.is_deleted)
 479                         continue;
 480                 done = tomoyo_io_printf(head, TOMOYO_KEYWORD_FILE_PATTERN
 481                                         "%s\n", ptr->pattern->name);
 482                 if (!done)
 483                         break;
 484         }
 485         return done;
 486 }
 487
 488 static bool tomoyo_same_no_rewrite(const struct tomoyo_acl_head *a,
 489                                    const struct tomoyo_acl_head *b)
 490 {
 491         return container_of(a, struct tomoyo_no_rewrite_entry, head)->pattern
 492                 == container_of(b, struct tomoyo_no_rewrite_entry, head)
 493                 ->pattern;
 494 }
 495
 496 /**
 497  * tomoyo_update_no_rewrite_entry - Update "struct tomoyo_no_rewrite_entry" list.
 498  *
 499  * @pattern:   Pathname pattern that are not rewritable by default.
 500  * @is_delete: True if it is a delete request.
 501  *
 502  * Returns 0 on success, negative value otherwise.
 503  *
 504  * Caller holds tomoyo_read_lock().
 505  */
 506 static int tomoyo_update_no_rewrite_entry(const char *pattern,
 507                                           const bool is_delete)
 508 {
 509         struct tomoyo_no_rewrite_entry e = { };
 510         int error;
 511
 512         if (!tomoyo_correct_word(pattern))
 513                 return -EINVAL;
 514         e.pattern = tomoyo_get_name(pattern);
 515         if (!e.pattern)
 516                 return -ENOMEM;
 517         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
 518                                      &tomoyo_policy_list[TOMOYO_ID_NO_REWRITE],
 519                                      tomoyo_same_no_rewrite);
 520         tomoyo_put_name(e.pattern);
 521         return error;
 522 }
 523
 524 /**
 525  * tomoyo_no_rewrite_file - Check if the given pathname is not permitted to be rewrited.
 526  *
 527  * @filename: Filename to check.
 528  *
 529  * Returns true if @filename is specified by "deny_rewrite" directive,
 530  * false otherwise.
 531  *
 532  * Caller holds tomoyo_read_lock().
 533  */
 534 static bool tomoyo_no_rewrite_file(const struct tomoyo_path_info *filename)
 535 {
 536         struct tomoyo_no_rewrite_entry *ptr;
 537         bool found = false;
 538
 539         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_NO_REWRITE],
 540                                 head.list) {
 541                 if (ptr->head.is_deleted)
 542                         continue;
 543                 if (!tomoyo_path_matches_pattern(filename, ptr->pattern))
 544                         continue;
 545                 found = true;
 546                 break;
 547         }
 548         return found;
 549 }
 550
 551 /**
 552  * tomoyo_write_no_rewrite_policy - Write "struct tomoyo_no_rewrite_entry" list.
 553  *
 554  * @data:      String to parse.
 555  * @is_delete: True if it is a delete request.
 556  *
 557  * Returns 0 on success, negative value otherwise.
 558  *
 559  * Caller holds tomoyo_read_lock().
 560  */
 561 int tomoyo_write_no_rewrite_policy(char *data, const bool is_delete)
 562 {
 563         return tomoyo_update_no_rewrite_entry(data, is_delete);
 564 }
 565
 566 /**
 567  * tomoyo_read_no_rewrite_policy - Read "struct tomoyo_no_rewrite_entry" list.
 568  *
 569  * @head: Pointer to "struct tomoyo_io_buffer".
 570  *
 571  * Returns true on success, false otherwise.
 572  *
 573  * Caller holds tomoyo_read_lock().
 574  */
 575 bool tomoyo_read_no_rewrite_policy(struct tomoyo_io_buffer *head)
 576 {
 577         struct list_head *pos;
 578         bool done = true;
 579
 580         list_for_each_cookie(pos, head->read_var2,
 581                              &tomoyo_policy_list[TOMOYO_ID_NO_REWRITE]) {
 582                 struct tomoyo_no_rewrite_entry *ptr;
 583                 ptr = list_entry(pos, struct tomoyo_no_rewrite_entry,
 584                                  head.list);
 585                 if (ptr->head.is_deleted)
 586                         continue;
 587                 done = tomoyo_io_printf(head, TOMOYO_KEYWORD_DENY_REWRITE
 588                                         "%s\n", ptr->pattern->name);
 589                 if (!done)
 590                         break;
 591         }
 592         return done;
 593 }
 594
 595 static bool tomoyo_check_path_acl(const struct tomoyo_request_info *r,
 596                                   const struct tomoyo_acl_info *ptr)
 597 {
 598         const struct tomoyo_path_acl *acl = container_of(ptr, typeof(*acl),
 599                                                          head);
 600         return (acl->perm & (1 << r->param.path.operation)) &&
 601                 tomoyo_compare_name_union(r->param.path.filename, &acl->name);
 602 }
 603
 604 static bool tomoyo_check_path_number_acl(const struct tomoyo_request_info *r,
 605                                          const struct tomoyo_acl_info *ptr)
 606 {
 607         const struct tomoyo_path_number_acl *acl =
 608                 container_of(ptr, typeof(*acl), head);
 609         return (acl->perm & (1 << r->param.path_number.operation)) &&
 610                 tomoyo_compare_number_union(r->param.path_number.number,
 611                                             &acl->number) &&
 612                 tomoyo_compare_name_union(r->param.path_number.filename,
 613                                           &acl->name);
 614 }
 615
 616 static bool tomoyo_check_path2_acl(const struct tomoyo_request_info *r,
 617                                    const struct tomoyo_acl_info *ptr)
 618 {
 619         const struct tomoyo_path2_acl *acl =
 620                 container_of(ptr, typeof(*acl), head);
 621         return (acl->perm & (1 << r->param.path2.operation)) &&
 622                 tomoyo_compare_name_union(r->param.path2.filename1, &acl->name1)
 623                 && tomoyo_compare_name_union(r->param.path2.filename2,
 624                                              &acl->name2);
 625 }
 626
 627 static bool tomoyo_check_mkdev_acl(const struct tomoyo_request_info *r,
 628                                 const struct tomoyo_acl_info *ptr)
 629 {
 630         const struct tomoyo_mkdev_acl *acl =
 631                 container_of(ptr, typeof(*acl), head);
 632         return (acl->perm & (1 << r->param.mkdev.operation)) &&
 633                 tomoyo_compare_number_union(r->param.mkdev.mode,
 634                                             &acl->mode) &&
 635                 tomoyo_compare_number_union(r->param.mkdev.major,
 636                                             &acl->major) &&
 637                 tomoyo_compare_number_union(r->param.mkdev.minor,
 638                                             &acl->minor) &&
 639                 tomoyo_compare_name_union(r->param.mkdev.filename,
 640                                           &acl->name);
 641 }
 642
 643 static bool tomoyo_same_path_acl(const struct tomoyo_acl_info *a,
 644                                  const struct tomoyo_acl_info *b)
 645 {
 646         const struct tomoyo_path_acl *p1 = container_of(a, typeof(*p1), head);
 647         const struct tomoyo_path_acl *p2 = container_of(b, typeof(*p2), head);
 648         return tomoyo_same_acl_head(&p1->head, &p2->head) &&
 649                 tomoyo_same_name_union(&p1->name, &p2->name);
 650 }
 651
 652 static bool tomoyo_merge_path_acl(struct tomoyo_acl_info *a,
 653                                   struct tomoyo_acl_info *b,
 654                                   const bool is_delete)
 655 {
 656         u16 * const a_perm = &container_of(a, struct tomoyo_path_acl, head)
 657                 ->perm;
 658         u16 perm = *a_perm;
 659         const u16 b_perm = container_of(b, struct tomoyo_path_acl, head)->perm;
 660         if (is_delete) {
 661                 perm &= ~b_perm;
 662                 if ((perm & TOMOYO_RW_MASK) != TOMOYO_RW_MASK)
 663                         perm &= ~(1 << TOMOYO_TYPE_READ_WRITE);
 664                 else if (!(perm & (1 << TOMOYO_TYPE_READ_WRITE)))
 665                         perm &= ~TOMOYO_RW_MASK;
 666         } else {
 667                 perm |= b_perm;
 668                 if ((perm & TOMOYO_RW_MASK) == TOMOYO_RW_MASK)
 669                         perm |= (1 << TOMOYO_TYPE_READ_WRITE);
 670                 else if (perm & (1 << TOMOYO_TYPE_READ_WRITE))
 671                         perm |= TOMOYO_RW_MASK;
 672         }
 673         *a_perm = perm;
 674         return !perm;
 675 }
 676
 677 /**
 678  * tomoyo_update_path_acl - Update "struct tomoyo_path_acl" list.
 679  *
 680  * @type:      Type of operation.
 681  * @filename:  Filename.
 682  * @domain:    Pointer to "struct tomoyo_domain_info".
 683  * @is_delete: True if it is a delete request.
 684  *
 685  * Returns 0 on success, negative value otherwise.
 686  *
 687  * Caller holds tomoyo_read_lock().
 688  */
 689 static int tomoyo_update_path_acl(const u8 type, const char *filename,
 690                                   struct tomoyo_domain_info * const domain,
 691                                   const bool is_delete)
 692 {
 693         struct tomoyo_path_acl e = {
 694                 .head.type = TOMOYO_TYPE_PATH_ACL,
 695                 .perm = 1 << type
 696         };
 697         int error;
 698         if (e.perm == (1 << TOMOYO_TYPE_READ_WRITE))
 699                 e.perm |= TOMOYO_RW_MASK;
 700         if (!tomoyo_parse_name_union(filename, &e.name))
 701                 return -EINVAL;
 702         error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
 703                                      tomoyo_same_path_acl,
 704                                      tomoyo_merge_path_acl);
 705         tomoyo_put_name_union(&e.name);
 706         return error;
 707 }
 708
 709 static bool tomoyo_same_mkdev_acl(const struct tomoyo_acl_info *a,
 710                                          const struct tomoyo_acl_info *b)
 711 {
 712         const struct tomoyo_mkdev_acl *p1 = container_of(a, typeof(*p1),
 713                                                                 head);
 714         const struct tomoyo_mkdev_acl *p2 = container_of(b, typeof(*p2),
 715                                                                 head);
 716         return tomoyo_same_acl_head(&p1->head, &p2->head)
 717                 && tomoyo_same_name_union(&p1->name, &p2->name)
 718                 && tomoyo_same_number_union(&p1->mode, &p2->mode)
 719                 && tomoyo_same_number_union(&p1->major, &p2->major)
 720                 && tomoyo_same_number_union(&p1->minor, &p2->minor);
 721 }
 722
 723 static bool tomoyo_merge_mkdev_acl(struct tomoyo_acl_info *a,
 724                                           struct tomoyo_acl_info *b,
 725                                           const bool is_delete)
 726 {
 727         u8 *const a_perm = &container_of(a, struct tomoyo_mkdev_acl,
 728                                          head)->perm;
 729         u8 perm = *a_perm;
 730         const u8 b_perm = container_of(b, struct tomoyo_mkdev_acl, head)
 731                 ->perm;
 732         if (is_delete)
 733                 perm &= ~b_perm;
 734         else
 735                 perm |= b_perm;
 736         *a_perm = perm;
 737         return !perm;
 738 }
 739
 740 /**
 741  * tomoyo_update_mkdev_acl - Update "struct tomoyo_mkdev_acl" list.
 742  *
 743  * @type:      Type of operation.
 744  * @filename:  Filename.
 745  * @mode:      Create mode.
 746  * @major:     Device major number.
 747  * @minor:     Device minor number.
 748  * @domain:    Pointer to "struct tomoyo_domain_info".
 749  * @is_delete: True if it is a delete request.
 750  *
 751  * Returns 0 on success, negative value otherwise.
 752  *
 753  * Caller holds tomoyo_read_lock().
 754  */
 755 static int tomoyo_update_mkdev_acl(const u8 type, const char *filename,
 756                                           char *mode, char *major, char *minor,
 757                                           struct tomoyo_domain_info * const
 758                                           domain, const bool is_delete)
 759 {
 760         struct tomoyo_mkdev_acl e = {
 761                 .head.type = TOMOYO_TYPE_MKDEV_ACL,
 762                 .perm = 1 << type
 763         };
 764         int error = is_delete ? -ENOENT : -ENOMEM;
 765         if (!tomoyo_parse_name_union(filename, &e.name) ||
 766             !tomoyo_parse_number_union(mode, &e.mode) ||
 767             !tomoyo_parse_number_union(major, &e.major) ||
 768             !tomoyo_parse_number_union(minor, &e.minor))
 769                 goto out;
 770         error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
 771                                      tomoyo_same_mkdev_acl,
 772                                      tomoyo_merge_mkdev_acl);
 773  out:
 774         tomoyo_put_name_union(&e.name);
 775         tomoyo_put_number_union(&e.mode);
 776         tomoyo_put_number_union(&e.major);
 777         tomoyo_put_number_union(&e.minor);
 778         return error;
 779 }
 780
 781 static bool tomoyo_same_path2_acl(const struct tomoyo_acl_info *a,
 782                                   const struct tomoyo_acl_info *b)
 783 {
 784         const struct tomoyo_path2_acl *p1 = container_of(a, typeof(*p1), head);
 785         const struct tomoyo_path2_acl *p2 = container_of(b, typeof(*p2), head);
 786         return tomoyo_same_acl_head(&p1->head, &p2->head)
 787                 && tomoyo_same_name_union(&p1->name1, &p2->name1)
 788                 && tomoyo_same_name_union(&p1->name2, &p2->name2);
 789 }
 790
 791 static bool tomoyo_merge_path2_acl(struct tomoyo_acl_info *a,
 792                                    struct tomoyo_acl_info *b,
 793                                    const bool is_delete)
 794 {
 795         u8 * const a_perm = &container_of(a, struct tomoyo_path2_acl, head)
 796                 ->perm;
 797         u8 perm = *a_perm;
 798         const u8 b_perm = container_of(b, struct tomoyo_path2_acl, head)->perm;
 799         if (is_delete)
 800                 perm &= ~b_perm;
 801         else
 802                 perm |= b_perm;
 803         *a_perm = perm;
 804         return !perm;
 805 }
 806
 807 /**
 808  * tomoyo_update_path2_acl - Update "struct tomoyo_path2_acl" list.
 809  *
 810  * @type:      Type of operation.
 811  * @filename1: First filename.
 812  * @filename2: Second filename.
 813  * @domain:    Pointer to "struct tomoyo_domain_info".
 814  * @is_delete: True if it is a delete request.
 815  *
 816  * Returns 0 on success, negative value otherwise.
 817  *
 818  * Caller holds tomoyo_read_lock().
 819  */
 820 static int tomoyo_update_path2_acl(const u8 type, const char *filename1,
 821                                    const char *filename2,
 822                                    struct tomoyo_domain_info * const domain,
 823                                    const bool is_delete)
 824 {
 825         struct tomoyo_path2_acl e = {
 826                 .head.type = TOMOYO_TYPE_PATH2_ACL,
 827                 .perm = 1 << type
 828         };
 829         int error = is_delete ? -ENOENT : -ENOMEM;
 830         if (!tomoyo_parse_name_union(filename1, &e.name1) ||
 831             !tomoyo_parse_name_union(filename2, &e.name2))
 832                 goto out;
 833         error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
 834                                      tomoyo_same_path2_acl,
 835                                      tomoyo_merge_path2_acl);
 836  out:
 837         tomoyo_put_name_union(&e.name1);
 838         tomoyo_put_name_union(&e.name2);
 839         return error;
 840 }
 841
 842 /**
 843  * tomoyo_path_permission - Check permission for single path operation.
 844  *
 845  * @r:         Pointer to "struct tomoyo_request_info".
 846  * @operation: Type of operation.
 847  * @filename:  Filename to check.
 848  *
 849  * Returns 0 on success, negative value otherwise.
 850  *
 851  * Caller holds tomoyo_read_lock().
 852  */
 853 int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
 854                            const struct tomoyo_path_info *filename)
 855 {
 856         int error;
 857
 858  next:
 859         r->type = tomoyo_p2mac[operation];
 860         r->mode = tomoyo_get_mode(r->profile, r->type);
 861         if (r->mode == TOMOYO_CONFIG_DISABLED)
 862                 return 0;
 863         r->param_type = TOMOYO_TYPE_PATH_ACL;
 864         r->param.path.filename = filename;
 865         r->param.path.operation = operation;
 866         do {
 867                 tomoyo_check_acl(r, tomoyo_check_path_acl);
 868                 if (!r->granted && operation == TOMOYO_TYPE_READ &&
 869                     !r->domain->ignore_global_allow_read &&
 870                     tomoyo_globally_readable_file(filename))
 871                         r->granted = true;
 872                 error = tomoyo_audit_path_log(r);
 873                 /*
 874                  * Do not retry for execute request, for alias may have
 875                  * changed.
 876                  */
 877         } while (error == TOMOYO_RETRY_REQUEST &&
 878                  operation != TOMOYO_TYPE_EXECUTE);
 879         /*
 880          * Since "allow_truncate" doesn't imply "allow_rewrite" permission,
 881          * we need to check "allow_rewrite" permission if the filename is
 882          * specified by "deny_rewrite" keyword.
 883          */
 884         if (!error && operation == TOMOYO_TYPE_TRUNCATE &&
 885             tomoyo_no_rewrite_file(filename)) {
 886                 operation = TOMOYO_TYPE_REWRITE;
 887                 goto next;
 888         }
 889         return error;
 890 }
 891
 892 static bool tomoyo_same_path_number_acl(const struct tomoyo_acl_info *a,
 893                                         const struct tomoyo_acl_info *b)
 894 {
 895         const struct tomoyo_path_number_acl *p1 = container_of(a, typeof(*p1),
 896                                                                head);
 897         const struct tomoyo_path_number_acl *p2 = container_of(b, typeof(*p2),
 898                                                                head);
 899         return tomoyo_same_acl_head(&p1->head, &p2->head)
 900                 && tomoyo_same_name_union(&p1->name, &p2->name)
 901                 && tomoyo_same_number_union(&p1->number, &p2->number);
 902 }
 903
 904 static bool tomoyo_merge_path_number_acl(struct tomoyo_acl_info *a,
 905                                          struct tomoyo_acl_info *b,
 906                                          const bool is_delete)
 907 {
 908         u8 * const a_perm = &container_of(a, struct tomoyo_path_number_acl,
 909                                           head)->perm;
 910         u8 perm = *a_perm;
 911         const u8 b_perm = container_of(b, struct tomoyo_path_number_acl, head)
 912                 ->perm;
 913         if (is_delete)
 914                 perm &= ~b_perm;
 915         else
 916                 perm |= b_perm;
 917         *a_perm = perm;
 918         return !perm;
 919 }
 920
 921 /**
 922  * tomoyo_update_path_number_acl - Update ioctl/chmod/chown/chgrp ACL.
 923  *
 924  * @type:      Type of operation.
 925  * @filename:  Filename.
 926  * @number:    Number.
 927  * @domain:    Pointer to "struct tomoyo_domain_info".
 928  * @is_delete: True if it is a delete request.
 929  *
 930  * Returns 0 on success, negative value otherwise.
 931  */
 932 static int tomoyo_update_path_number_acl(const u8 type, const char *filename,
 933                                          char *number,
 934                                          struct tomoyo_domain_info * const
 935                                          domain,
 936                                          const bool is_delete)
 937 {
 938         struct tomoyo_path_number_acl e = {
 939                 .head.type = TOMOYO_TYPE_PATH_NUMBER_ACL,
 940                 .perm = 1 << type
 941         };
 942         int error = is_delete ? -ENOENT : -ENOMEM;
 943         if (!tomoyo_parse_name_union(filename, &e.name))
 944                 return -EINVAL;
 945         if (!tomoyo_parse_number_union(number, &e.number))
 946                 goto out;
 947         error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
 948                                      tomoyo_same_path_number_acl,
 949                                      tomoyo_merge_path_number_acl);
 950  out:
 951         tomoyo_put_name_union(&e.name);
 952         tomoyo_put_number_union(&e.number);
 953         return error;
 954 }
 955
 956 /**
 957  * tomoyo_path_number_perm - Check permission for "create", "mkdir", "mkfifo", "mksock", "ioctl", "chmod", "chown", "chgrp".
 958  *
 959  * @type:   Type of operation.
 960  * @path:   Pointer to "struct path".
 961  * @number: Number.
 962  *
 963  * Returns 0 on success, negative value otherwise.
 964  */
 965 int tomoyo_path_number_perm(const u8 type, struct path *path,
 966                             unsigned long number)
 967 {
 968         struct tomoyo_request_info r;
 969         int error = -ENOMEM;
 970         struct tomoyo_path_info buf;
 971         int idx;
 972
 973         if (tomoyo_init_request_info(&r, NULL, tomoyo_pn2mac[type])
 974             == TOMOYO_CONFIG_DISABLED || !path->mnt || !path->dentry)
 975                 return 0;
 976         idx = tomoyo_read_lock();
 977         if (!tomoyo_get_realpath(&buf, path))
 978                 goto out;
 979         if (type == TOMOYO_TYPE_MKDIR)
 980                 tomoyo_add_slash(&buf);
 981         r.param_type = TOMOYO_TYPE_PATH_NUMBER_ACL;
 982         r.param.path_number.operation = type;
 983         r.param.path_number.filename = &buf;
 984         r.param.path_number.number = number;
 985         do {
 986                 tomoyo_check_acl(&r, tomoyo_check_path_number_acl);
 987                 error = tomoyo_audit_path_number_log(&r);
 988         } while (error == TOMOYO_RETRY_REQUEST);
 989         kfree(buf.name);
 990  out:
 991         tomoyo_read_unlock(idx);
 992         if (r.mode != TOMOYO_CONFIG_ENFORCING)
 993                 error = 0;
 994         return error;
 995 }
 996
 997 /**
 998  * tomoyo_check_open_permission - Check permission for "read" and "write".
 999  *
1000  * @domain: Pointer to "struct tomoyo_domain_info".
1001  * @path:   Pointer to "struct path".
1002  * @flag:   Flags for open().
1003  *
1004  * Returns 0 on success, negative value otherwise.
1005  */
1006 int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
1007                                  struct path *path, const int flag)
1008 {
1009         const u8 acc_mode = ACC_MODE(flag);
1010         int error = -ENOMEM;
1011         struct tomoyo_path_info buf;
1012         struct tomoyo_request_info r;
1013         int idx;
1014
1015         if (!path->mnt ||
1016             (path->dentry->d_inode && S_ISDIR(path->dentry->d_inode->i_mode)))
1017                 return 0;
1018         buf.name = NULL;
1019         r.mode = TOMOYO_CONFIG_DISABLED;
1020         idx = tomoyo_read_lock();
1021         if (!tomoyo_get_realpath(&buf, path))
1022                 goto out;
1023         error = 0;
1024         /*
1025          * If the filename is specified by "deny_rewrite" keyword,
1026          * we need to check "allow_rewrite" permission when the filename is not
1027          * opened for append mode or the filename is truncated at open time.
1028          */
1029         if ((acc_mode & MAY_WRITE) && !(flag & O_APPEND)
1030             && tomoyo_init_request_info(&r, domain, TOMOYO_MAC_FILE_REWRITE)
1031             != TOMOYO_CONFIG_DISABLED) {
1032                 if (!tomoyo_get_realpath(&buf, path)) {
1033                         error = -ENOMEM;
1034                         goto out;
1035                 }
1036                 if (tomoyo_no_rewrite_file(&buf))
1037                         error = tomoyo_path_permission(&r, TOMOYO_TYPE_REWRITE,
1038                                                        &buf);
1039         }
1040         if (!error && acc_mode &&
1041             tomoyo_init_request_info(&r, domain, TOMOYO_MAC_FILE_OPEN)
1042             != TOMOYO_CONFIG_DISABLED) {
1043                 u8 operation;
1044                 if (!buf.name && !tomoyo_get_realpath(&buf, path)) {
1045                         error = -ENOMEM;
1046                         goto out;
1047                 }
1048                 if (acc_mode == (MAY_READ | MAY_WRITE))
1049                         operation = TOMOYO_TYPE_READ_WRITE;
1050                 else if (acc_mode == MAY_READ)
1051                         operation = TOMOYO_TYPE_READ;
1052                 else
1053                         operation = TOMOYO_TYPE_WRITE;
1054                 error = tomoyo_path_permission(&r, operation, &buf);
1055         }
1056  out:
1057         kfree(buf.name);
1058         tomoyo_read_unlock(idx);
1059         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1060                 error = 0;
1061         return error;
1062 }
1063
1064 /**
1065  * tomoyo_path_perm - Check permission for "unlink", "rmdir", "truncate", "symlink", "rewrite", "chroot" and "unmount".
1066  *
1067  * @operation: Type of operation.
1068  * @path:      Pointer to "struct path".
1069  *
1070  * Returns 0 on success, negative value otherwise.
1071  */
1072 int tomoyo_path_perm(const u8 operation, struct path *path)
1073 {
1074         int error = -ENOMEM;
1075         struct tomoyo_path_info buf;
1076         struct tomoyo_request_info r;
1077         int idx;
1078
1079         if (!path->mnt)
1080                 return 0;
1081         if (tomoyo_init_request_info(&r, NULL, tomoyo_p2mac[operation])
1082             == TOMOYO_CONFIG_DISABLED)
1083                 return 0;
1084         buf.name = NULL;
1085         idx = tomoyo_read_lock();
1086         if (!tomoyo_get_realpath(&buf, path))
1087                 goto out;
1088         switch (operation) {
1089         case TOMOYO_TYPE_REWRITE:
1090                 if (!tomoyo_no_rewrite_file(&buf)) {
1091                         error = 0;
1092                         goto out;
1093                 }
1094                 break;
1095         case TOMOYO_TYPE_RMDIR:
1096         case TOMOYO_TYPE_CHROOT:
1097         case TOMOYO_TYPE_UMOUNT:
1098                 tomoyo_add_slash(&buf);
1099                 break;
1100         }
1101         error = tomoyo_path_permission(&r, operation, &buf);
1102  out:
1103         kfree(buf.name);
1104         tomoyo_read_unlock(idx);
1105         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1106                 error = 0;
1107         return error;
1108 }
1109
1110 /**
1111  * tomoyo_mkdev_perm - Check permission for "mkblock" and "mkchar".
1112  *
1113  * @operation: Type of operation. (TOMOYO_TYPE_MKCHAR or TOMOYO_TYPE_MKBLOCK)
1114  * @path:      Pointer to "struct path".
1115  * @mode:      Create mode.
1116  * @dev:       Device number.
1117  *
1118  * Returns 0 on success, negative value otherwise.
1119  */
1120 int tomoyo_mkdev_perm(const u8 operation, struct path *path,
1121                              const unsigned int mode, unsigned int dev)
1122 {
1123         struct tomoyo_request_info r;
1124         int error = -ENOMEM;
1125         struct tomoyo_path_info buf;
1126         int idx;
1127
1128         if (!path->mnt ||
1129             tomoyo_init_request_info(&r, NULL, tomoyo_pnnn2mac[operation])
1130             == TOMOYO_CONFIG_DISABLED)
1131                 return 0;
1132         idx = tomoyo_read_lock();
1133         error = -ENOMEM;
1134         if (tomoyo_get_realpath(&buf, path)) {
1135                 dev = new_decode_dev(dev);
1136                 r.param_type = TOMOYO_TYPE_MKDEV_ACL;
1137                 r.param.mkdev.filename = &buf;
1138                 r.param.mkdev.operation = operation;
1139                 r.param.mkdev.mode = mode;
1140                 r.param.mkdev.major = MAJOR(dev);
1141                 r.param.mkdev.minor = MINOR(dev);
1142                 tomoyo_check_acl(&r, tomoyo_check_mkdev_acl);
1143                 error = tomoyo_audit_mkdev_log(&r);
1144                 kfree(buf.name);
1145         }
1146         tomoyo_read_unlock(idx);
1147         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1148                 error = 0;
1149         return error;
1150 }
1151
1152 /**
1153  * tomoyo_path2_perm - Check permission for "rename", "link" and "pivot_root".
1154  *
1155  * @operation: Type of operation.
1156  * @path1:      Pointer to "struct path".
1157  * @path2:      Pointer to "struct path".
1158  *
1159  * Returns 0 on success, negative value otherwise.
1160  */
1161 int tomoyo_path2_perm(const u8 operation, struct path *path1,
1162                       struct path *path2)
1163 {
1164         int error = -ENOMEM;
1165         struct tomoyo_path_info buf1;
1166         struct tomoyo_path_info buf2;
1167         struct tomoyo_request_info r;
1168         int idx;
1169
1170         if (!path1->mnt || !path2->mnt ||
1171             tomoyo_init_request_info(&r, NULL, tomoyo_pp2mac[operation])
1172             == TOMOYO_CONFIG_DISABLED)
1173                 return 0;
1174         buf1.name = NULL;
1175         buf2.name = NULL;
1176         idx = tomoyo_read_lock();
1177         if (!tomoyo_get_realpath(&buf1, path1) ||
1178             !tomoyo_get_realpath(&buf2, path2))
1179                 goto out;
1180         switch (operation) {
1181                 struct dentry *dentry;
1182         case TOMOYO_TYPE_RENAME:
1183         case TOMOYO_TYPE_LINK:
1184                 dentry = path1->dentry;
1185                 if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
1186                         break;
1187                 /* fall through */
1188         case TOMOYO_TYPE_PIVOT_ROOT:
1189                 tomoyo_add_slash(&buf1);
1190                 tomoyo_add_slash(&buf2);
1191                 break;
1192         }
1193         r.param_type = TOMOYO_TYPE_PATH2_ACL;
1194         r.param.path2.operation = operation;
1195         r.param.path2.filename1 = &buf1;
1196         r.param.path2.filename2 = &buf2;
1197         do {
1198                 tomoyo_check_acl(&r, tomoyo_check_path2_acl);
1199                 error = tomoyo_audit_path2_log(&r);
1200         } while (error == TOMOYO_RETRY_REQUEST);
1201  out:
1202         kfree(buf1.name);
1203         kfree(buf2.name);
1204         tomoyo_read_unlock(idx);
1205         if (r.mode != TOMOYO_CONFIG_ENFORCING)
1206                 error = 0;
1207         return error;
1208 }
1209
1210 /**
1211  * tomoyo_write_file_policy - Update file related list.
1212  *
1213  * @data:      String to parse.
1214  * @domain:    Pointer to "struct tomoyo_domain_info".
1215  * @is_delete: True if it is a delete request.
1216  *
1217  * Returns 0 on success, negative value otherwise.
1218  *
1219  * Caller holds tomoyo_read_lock().
1220  */
1221 int tomoyo_write_file_policy(char *data, struct tomoyo_domain_info *domain,
1222                              const bool is_delete)
1223 {
1224         char *w[5];
1225         u8 type;
1226         if (!tomoyo_tokenize(data, w, sizeof(w)) || !w[1][0])
1227                 return -EINVAL;
1228         if (strncmp(w[0], "allow_", 6))
1229                 goto out;
1230         w[0] += 6;
1231         for (type = 0; type < TOMOYO_MAX_PATH_OPERATION; type++) {
1232                 if (strcmp(w[0], tomoyo_path_keyword[type]))
1233                         continue;
1234                 return tomoyo_update_path_acl(type, w[1], domain, is_delete);
1235         }
1236         if (!w[2][0])
1237                 goto out;
1238         for (type = 0; type < TOMOYO_MAX_PATH2_OPERATION; type++) {
1239                 if (strcmp(w[0], tomoyo_path2_keyword[type]))
1240                         continue;
1241                 return tomoyo_update_path2_acl(type, w[1], w[2], domain,
1242                                                is_delete);
1243         }
1244         for (type = 0; type < TOMOYO_MAX_PATH_NUMBER_OPERATION; type++) {
1245                 if (strcmp(w[0], tomoyo_path_number_keyword[type]))
1246                         continue;
1247                 return tomoyo_update_path_number_acl(type, w[1], w[2], domain,
1248                                                      is_delete);
1249         }
1250         if (!w[3][0] || !w[4][0])
1251                 goto out;
1252         for (type = 0; type < TOMOYO_MAX_MKDEV_OPERATION; type++) {
1253                 if (strcmp(w[0], tomoyo_mkdev_keyword[type]))
1254                         continue;
1255                 return tomoyo_update_mkdev_acl(type, w[1], w[2], w[3],
1256                                                w[4], domain, is_delete);
1257         }
1258  out:
1259         return -EINVAL;
1260 }