includes/filerepo/backend/FSFileBackend.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup FileBackend
   5  * @author Aaron Schulz
   6  */
   7
   8 /**
   9  * Class for a file system (FS) based file backend.
  10  *
  11  * All "containers" each map to a directory under the backend's base directory.
  12  * For backwards-compatibility, some container paths can be set to custom paths.
  13  * The wiki ID will not be used in any custom paths, so this should be avoided.
  14  * Sharding can be accomplished by using FileRepo-style hash paths.
  15  *
  16  * Status messages should avoid mentioning the internal FS paths.
  17  * Likewise, error suppression should be used to avoid path disclosure.
  18  *
  19  * @ingroup FileBackend
  20  */
  21 class FSFileBackend extends FileBackend {
  22         protected $basePath; // string; directory holding the container directories
  23         /** @var Array Map of container names to root paths */
  24         protected $containerPaths = array(); // for custom container paths
  25         protected $fileMode; // integer; file permission mode
  26
  27         /**
  28          * @see FileBackend::__construct()
  29          * Additional $config params include:
  30          *    basePath       : File system directory that holds containers.
  31          *    containerPaths : Map of container names to custom file system directories.
  32          *                     This should only be used for backwards-compatibility.
  33          *    fileMode       : Octal UNIX file permissions to use on files stored.
  34          */
  35         public function __construct( array $config ) {
  36                 parent::__construct( $config );
  37                 if ( isset( $config['basePath'] ) ) {
  38                         if ( substr( $this->basePath, -1 ) === '/' ) {
  39                                 $this->basePath = substr( $this->basePath, 0, -1 ); // remove trailing slash
  40                         }
  41                 } else {
  42                         $this->basePath = null; // none; containers must have explicit paths
  43                 }
  44                 $this->containerPaths = (array)$config['containerPaths'];
  45                 foreach ( $this->containerPaths as &$path ) {
  46                         if ( substr( $path, -1 ) === '/' ) {
  47                                 $path = substr( $path, 0, -1 ); // remove trailing slash
  48                         }
  49                 }
  50                 $this->fileMode = isset( $config['fileMode'] )
  51                         ? $config['fileMode']
  52                         : 0644;
  53         }
  54
  55         /**
  56          * @see FileBackend::resolveContainerPath()
  57          */
  58         protected function resolveContainerPath( $container, $relStoragePath ) {
  59                 if ( isset( $this->containerPaths[$container] ) || isset( $this->basePath ) ) {
  60                         return $relStoragePath; // container has a root directory
  61                 }
  62                 return null;
  63         }
  64
  65         /**
  66          * Given the short (unresolved) and full (resolved) name of
  67          * a container, return the file system path of the container.
  68          *
  69          * @param $shortCont string
  70          * @param $fullCont string
  71          * @return string|null
  72          */
  73         protected function containerFSRoot( $shortCont, $fullCont ) {
  74                 if ( isset( $this->containerPaths[$shortCont] ) ) {
  75                         return $this->containerPaths[$shortCont];
  76                 } elseif ( isset( $this->basePath ) ) {
  77                         return "{$this->basePath}/{$fullCont}";
  78                 }
  79                 return null; // no container base path defined
  80         }
  81
  82         /**
  83          * Get the absolute file system path for a storage path
  84          *
  85          * @param $storagePath string Storage path
  86          * @return string|null
  87          */
  88         protected function resolveToFSPath( $storagePath ) {
  89                 list( $fullCont, $relPath ) = $this->resolveStoragePathReal( $storagePath );
  90                 if ( $relPath === null ) {
  91                         return null; // invalid
  92                 }
  93                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $storagePath );
  94                 $fsPath = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
  95                 if ( $relPath != '' ) {
  96                         $fsPath .= "/{$relPath}";
  97                 }
  98                 return $fsPath;
  99         }
 100
 101         /**
 102          * @see FileBackend::doStoreInternal()
 103          */
 104         protected function doStoreInternal( array $params ) {
 105                 $status = Status::newGood();
 106
 107                 $dest = $this->resolveToFSPath( $params['dst'] );
 108                 if ( $dest === null ) {
 109                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 110                         return $status;
 111                 }
 112
 113                 if ( file_exists( $dest ) ) {
 114                         if ( !empty( $params['overwriteDest'] ) ) {
 115                                 wfSuppressWarnings();
 116                                 $ok = unlink( $dest );
 117                                 wfRestoreWarnings();
 118                                 if ( !$ok ) {
 119                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 120                                         return $status;
 121                                 }
 122                         } else {
 123                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 124                                 return $status;
 125                         }
 126                 } else {
 127                         if ( !wfMkdirParents( dirname( $dest ) ) ) {
 128                                 $status->fatal( 'directorycreateerror', $params['dst'] );
 129                                 return $status;
 130                         }
 131                 }
 132
 133                 wfSuppressWarnings();
 134                 $ok = copy( $params['src'], $dest );
 135                 wfRestoreWarnings();
 136                 if ( !$ok ) {
 137                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 138                         return $status;
 139                 }
 140
 141                 $this->chmod( $dest );
 142
 143                 return $status;
 144         }
 145
 146         /**
 147          * @see FileBackend::doCopyInternal()
 148          */
 149         protected function doCopyInternal( array $params ) {
 150                 $status = Status::newGood();
 151
 152                 $source = $this->resolveToFSPath( $params['src'] );
 153                 if ( $source === null ) {
 154                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 155                         return $status;
 156                 }
 157
 158                 $dest = $this->resolveToFSPath( $params['dst'] );
 159                 if ( $dest === null ) {
 160                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 161                         return $status;
 162                 }
 163
 164                 if ( file_exists( $dest ) ) {
 165                         if ( !empty( $params['overwriteDest'] ) ) {
 166                                 wfSuppressWarnings();
 167                                 $ok = unlink( $dest );
 168                                 wfRestoreWarnings();
 169                                 if ( !$ok ) {
 170                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 171                                         return $status;
 172                                 }
 173                         } else {
 174                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 175                                 return $status;
 176                         }
 177                 } else {
 178                         if ( !wfMkdirParents( dirname( $dest ) ) ) {
 179                                 $status->fatal( 'directorycreateerror', $params['dst'] );
 180                                 return $status;
 181                         }
 182                 }
 183
 184                 wfSuppressWarnings();
 185                 $ok = copy( $source, $dest );
 186                 wfRestoreWarnings();
 187                 if ( !$ok ) {
 188                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 189                         return $status;
 190                 }
 191
 192                 $this->chmod( $dest );
 193
 194                 return $status;
 195         }
 196
 197         /**
 198          * @see FileBackend::doMoveInternal()
 199          */
 200         protected function doMoveInternal( array $params ) {
 201                 $status = Status::newGood();
 202
 203                 $source = $this->resolveToFSPath( $params['src'] );
 204                 if ( $source === null ) {
 205                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 206                         return $status;
 207                 }
 208
 209                 $dest = $this->resolveToFSPath( $params['dst'] );
 210                 if ( $dest === null ) {
 211                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 212                         return $status;
 213                 }
 214
 215                 if ( file_exists( $dest ) ) {
 216                         if ( !empty( $params['overwriteDest'] ) ) {
 217                                 // Windows does not support moving over existing files
 218                                 if ( wfIsWindows() ) {
 219                                         wfSuppressWarnings();
 220                                         $ok = unlink( $dest );
 221                                         wfRestoreWarnings();
 222                                         if ( !$ok ) {
 223                                                 $status->fatal( 'backend-fail-delete', $params['dst'] );
 224                                                 return $status;
 225                                         }
 226                                 }
 227                         } else {
 228                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 229                                 return $status;
 230                         }
 231                 } else {
 232                         if ( !wfMkdirParents( dirname( $dest ) ) ) {
 233                                 $status->fatal( 'directorycreateerror', $params['dst'] );
 234                                 return $status;
 235                         }
 236                 }
 237
 238                 wfSuppressWarnings();
 239                 $ok = rename( $source, $dest );
 240                 clearstatcache(); // file no longer at source
 241                 wfRestoreWarnings();
 242                 if ( !$ok ) {
 243                         $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 244                         return $status;
 245                 }
 246
 247                 return $status;
 248         }
 249
 250         /**
 251          * @see FileBackend::doDeleteInternal()
 252          */
 253         protected function doDeleteInternal( array $params ) {
 254                 $status = Status::newGood();
 255
 256                 $source = $this->resolveToFSPath( $params['src'] );
 257                 if ( $source === null ) {
 258                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 259                         return $status;
 260                 }
 261
 262                 if ( !is_file( $source ) ) {
 263                         if ( empty( $params['ignoreMissingSource'] ) ) {
 264                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 265                         }
 266                         return $status; // do nothing; either OK or bad status
 267                 }
 268
 269                 wfSuppressWarnings();
 270                 $ok = unlink( $source );
 271                 wfRestoreWarnings();
 272                 if ( !$ok ) {
 273                         $status->fatal( 'backend-fail-delete', $params['src'] );
 274                         return $status;
 275                 }
 276
 277                 return $status;
 278         }
 279
 280         /**
 281          * @see FileBackend::doCreateInternal()
 282          */
 283         protected function doCreateInternal( array $params ) {
 284                 $status = Status::newGood();
 285
 286                 $dest = $this->resolveToFSPath( $params['dst'] );
 287                 if ( $dest === null ) {
 288                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 289                         return $status;
 290                 }
 291
 292                 if ( file_exists( $dest ) ) {
 293                         if ( !empty( $params['overwriteDest'] ) ) {
 294                                 wfSuppressWarnings();
 295                                 $ok = unlink( $dest );
 296                                 wfRestoreWarnings();
 297                                 if ( !$ok ) {
 298                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 299                                         return $status;
 300                                 }
 301                         } else {
 302                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 303                                 return $status;
 304                         }
 305                 } else {
 306                         if ( !wfMkdirParents( dirname( $dest ) ) ) {
 307                                 $status->fatal( 'directorycreateerror', $params['dst'] );
 308                                 return $status;
 309                         }
 310                 }
 311
 312                 wfSuppressWarnings();
 313                 $ok = file_put_contents( $dest, $params['content'] );
 314                 wfRestoreWarnings();
 315                 if ( !$ok ) {
 316                         $status->fatal( 'backend-fail-create', $params['dst'] );
 317                         return $status;
 318                 }
 319
 320                 $this->chmod( $dest );
 321
 322                 return $status;
 323         }
 324
 325         /**
 326          * @see FileBackend::doPrepareInternal()
 327          */
 328         protected function doPrepareInternal( $fullCont, $dirRel, array $params ) {
 329                 $status = Status::newGood();
 330                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 331                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 332                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 333                 if ( !wfMkdirParents( $dir ) ) {
 334                         $status->fatal( 'directorycreateerror', $params['dir'] );
 335                 } elseif ( !is_writable( $dir ) ) {
 336                         $status->fatal( 'directoryreadonlyerror', $params['dir'] );
 337                 } elseif ( !is_readable( $dir ) ) {
 338                         $status->fatal( 'directorynotreadableerror', $params['dir'] );
 339                 }
 340                 return $status;
 341         }
 342
 343         /**
 344          * @see FileBackend::doSecureInternal()
 345          */
 346         protected function doSecureInternal( $fullCont, $dirRel, array $params ) {
 347                 $status = Status::newGood();
 348                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 349                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 350                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 351                 if ( !wfMkdirParents( $dir ) ) {
 352                         $status->fatal( 'directorycreateerror', $params['dir'] );
 353                         return $status;
 354                 }
 355                 // Seed new directories with a blank index.html, to prevent crawling...
 356                 if ( !empty( $params['noListing'] ) && !file_exists( "{$dir}/index.html" ) ) {
 357                         wfSuppressWarnings();
 358                         $ok = file_put_contents( "{$dir}/index.html", '' );
 359                         wfRestoreWarnings();
 360                         if ( !$ok ) {
 361                                 $status->fatal( 'backend-fail-create', $params['dir'] . '/index.html' );
 362                                 return $status;
 363                         }
 364                 }
 365                 // Add a .htaccess file to the root of the container...
 366                 if ( !empty( $params['noAccess'] ) ) {
 367                         $dirRoot = $this->resolveToFSPath( $params['dir'], '' );
 368                         if ( !file_exists( "{$dirRoot}/.htaccess" ) ) {
 369                                 wfSuppressWarnings();
 370                                 $ok = file_put_contents( "{$dirRoot}/.htaccess", "Deny from all\n" );
 371                                 wfRestoreWarnings();
 372                                 if ( !$ok ) {
 373                                         $storeDir = "mwstore://{$this->name}/{$shortCont}";
 374                                         $status->fatal( 'backend-fail-create', "$storeDir/.htaccess" );
 375                                         return $status;
 376                                 }
 377                         }
 378                 }
 379                 return $status;
 380         }
 381
 382         /**
 383          * @see FileBackend::doCleanInternal()
 384          */
 385         protected function doCleanInternal( $fullCont, $dirRel, array $params ) {
 386                 $status = Status::newGood();
 387                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 388                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 389                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 390                 wfSuppressWarnings();
 391                 if ( is_dir( $dir ) ) {
 392                         rmdir( $dir ); // remove directory if empty
 393                 }
 394                 wfRestoreWarnings();
 395                 return $status;
 396         }
 397
 398         /**
 399          * @see FileBackend::doFileExists()
 400          */
 401         protected function doGetFileStat( array $params ) {
 402                 $source = $this->resolveToFSPath( $params['src'] );
 403                 if ( $source === null ) {
 404                         return false; // invalid storage path
 405                 }
 406
 407                 wfSuppressWarnings();
 408                 $stat = is_file( $source ) ? stat( $source ) : false; // regular files only
 409                 wfRestoreWarnings();
 410
 411                 if ( $stat ) {
 412                         return array(
 413                                 'mtime' => wfTimestamp( TS_MW, $stat['mtime'] ),
 414                                 'size'  => $stat['size']
 415                         );
 416                 } else {
 417                         return false;
 418                 }
 419         }
 420
 421         /**
 422          * @see FileBackend::getFileListInternal()
 423          */
 424         public function getFileListInternal( $fullCont, $dirRel, array $params ) {
 425                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 426                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 427                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 428                 wfSuppressWarnings();
 429                 $exists = is_dir( $dir );
 430                 wfRestoreWarnings();
 431                 if ( !$exists ) {
 432                         return array(); // nothing under this dir
 433                 }
 434                 wfSuppressWarnings();
 435                 $readable = is_readable( $dir );
 436                 wfRestoreWarnings();
 437                 if ( !$readable ) {
 438                         return null; // bad permissions?
 439                 }
 440                 return new FSFileIterator( $dir );
 441         }
 442
 443         /**
 444          * @see FileBackend::getLocalReference()
 445          */
 446         public function getLocalReference( array $params ) {
 447                 $source = $this->resolveToFSPath( $params['src'] );
 448                 if ( $source === null ) {
 449                         return null;
 450                 }
 451                 return new FSFile( $source );
 452         }
 453
 454         /**
 455          * @see FileBackend::getLocalCopy()
 456          */
 457         public function getLocalCopy( array $params ) {
 458                 $source = $this->resolveToFSPath( $params['src'] );
 459                 if ( $source === null ) {
 460                         return null;
 461                 }
 462
 463                 // Create a new temporary file with the same extension...
 464                 $ext = FileBackend::extensionFromPath( $params['src'] );
 465                 $tmpFile = TempFSFile::factory( wfBaseName( $source ) . '_', $ext );
 466                 if ( !$tmpFile ) {
 467                         return null;
 468                 }
 469                 $tmpPath = $tmpFile->getPath();
 470
 471                 // Copy the source file over the temp file
 472                 wfSuppressWarnings();
 473                 $ok = copy( $source, $tmpPath );
 474                 wfRestoreWarnings();
 475                 if ( !$ok ) {
 476                         return null;
 477                 }
 478
 479                 $this->chmod( $tmpPath );
 480
 481                 return $tmpFile;
 482         }
 483
 484         /**
 485          * Chmod a file, suppressing the warnings
 486          *
 487          * @param $path string Absolute file system path
 488          * @return bool Success
 489          */
 490         protected function chmod( $path ) {
 491                 wfSuppressWarnings();
 492                 $ok = chmod( $path, $this->fileMode );
 493                 wfRestoreWarnings();
 494
 495                 return $ok;
 496         }
 497 }
 498
 499 /**
 500  * Wrapper around RecursiveDirectoryIterator that catches
 501  * exception or does any custom behavoir that we may want.
 502  *
 503  * @ingroup FileBackend
 504  */
 505 class FSFileIterator implements Iterator {
 506         /** @var RecursiveIteratorIterator */
 507         protected $iter;
 508         protected $suffixStart; // integer
 509
 510         /**
 511          * Get an FSFileIterator from a file system directory
 512          *
 513          * @param $dir string
 514          */
 515         public function __construct( $dir ) {
 516                 $this->suffixStart = strlen( realpath( $dir ) ) + 1; // size of "path/to/dir/"
 517                 try {
 518                         $flags = FilesystemIterator::CURRENT_AS_FILEINFO | FilesystemIterator::SKIP_DOTS;
 519                         $this->iter = new RecursiveIteratorIterator(
 520                                 new RecursiveDirectoryIterator( $dir, $flags ) );
 521                 } catch ( UnexpectedValueException $e ) {
 522                         $this->iter = null; // bad permissions? deleted?
 523                 }
 524         }
 525
 526         public function current() {
 527                 // Return only the relative path and normalize slashes to FileBackend-style
 528                 // Make sure to use the realpath since the suffix is based upon that
 529                 return str_replace( '\\', '/',
 530                         substr( realpath( $this->iter->current() ), $this->suffixStart ) );
 531         }
 532
 533         public function key() {
 534                 return $this->iter->key();
 535         }
 536
 537         public function next() {
 538                 try {
 539                         $this->iter->next();
 540                 } catch ( UnexpectedValueException $e ) {
 541                         $this->iter = null;
 542                 }
 543         }
 544
 545         public function rewind() {
 546                 try {
 547                         $this->iter->rewind();
 548                 } catch ( UnexpectedValueException $e ) {
 549                         $this->iter = null;
 550                 }
 551         }
 552
 553         public function valid() {
 554                 return $this->iter && $this->iter->valid();
 555         }
 556 }