includes/upload/UploadBase.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup upload
   5  *
   6  * UploadBase and subclasses are the backend of MediaWiki's file uploads.
   7  * The frontends are formed by ApiUpload and SpecialUpload.
   8  *
   9  * See also includes/docs/upload.txt
  10  *
  11  * @author Brion Vibber
  12  * @author Bryan Tong Minh
  13  * @author Michael Dale
  14  */
  15
  16 abstract class UploadBase {
  17         protected $mTempPath;
  18         protected $mDesiredDestName, $mDestName, $mRemoveTempFile, $mSourceType;
  19         protected $mTitle = false, $mTitleError = 0;
  20         protected $mFilteredName, $mFinalExtension;
  21         protected $mLocalFile;
  22
  23         const SUCCESS = 0;
  24         const OK = 0;
  25         const EMPTY_FILE = 3;
  26         const MIN_LENGTH_PARTNAME = 4;
  27         const ILLEGAL_FILENAME = 5;
  28         const OVERWRITE_EXISTING_FILE = 7;
  29         const FILETYPE_MISSING = 8;
  30         const FILETYPE_BADTYPE = 9;
  31         const VERIFICATION_ERROR = 10;
  32
  33         # HOOK_ABORTED is the new name of UPLOAD_VERIFICATION_ERROR
  34         const UPLOAD_VERIFICATION_ERROR = 11;
  35         const HOOK_ABORTED = 11;
  36         const FILE_TOO_LARGE = 12;
  37
  38         const SESSION_VERSION = 2;
  39         const SESSION_KEYNAME = 'wsUploadData';
  40
  41         static public function getSessionKeyname() {
  42                 return self::SESSION_KEYNAME;
  43         }
  44
  45         public function getVerificationErrorCode( $error ) {
  46                 $code_to_status = array(self::EMPTY_FILE => 'empty-file',
  47                                                                 self::FILE_TOO_LARGE => 'file-too-large',
  48                                                                 self::FILETYPE_MISSING => 'filetype-missing',
  49                                                                 self::FILETYPE_BADTYPE => 'filetype-banned',
  50                                                                 self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
  51                                                                 self::ILLEGAL_FILENAME => 'illegal-filename',
  52                                                                 self::OVERWRITE_EXISTING_FILE => 'overwrite',
  53                                                                 self::VERIFICATION_ERROR => 'verification-error',
  54                                                                 self::HOOK_ABORTED =>  'hookaborted',
  55                 );
  56                 if( isset( $code_to_status[$error] ) ) {
  57                         return $code_to_status[$error];
  58                 }
  59
  60                 return 'unknown-error';
  61         }
  62
  63         /**
  64          * Returns true if uploads are enabled.
  65          * Can be override by subclasses.
  66          */
  67         public static function isEnabled() {
  68                 global $wgEnableUploads;
  69                 if ( !$wgEnableUploads ) {
  70                         return false;
  71                 }
  72
  73                 # Check php's file_uploads setting
  74                 if( !wfIniGetBool( 'file_uploads' ) ) {
  75                         return false;
  76                 }
  77                 return true;
  78         }
  79
  80         /**
  81          * Returns true if the user can use this upload module or else a string
  82          * identifying the missing permission.
  83          * Can be overriden by subclasses.
  84          */
  85         public static function isAllowed( $user ) {
  86                 if( !$user->isAllowed( 'upload' ) ) {
  87                         return 'upload';
  88                 }
  89                 return true;
  90         }
  91
  92         // Upload handlers. Should probably just be a global.
  93         static $uploadHandlers = array( 'Stash', 'File', 'Url' );
  94
  95         /**
  96          * Create a form of UploadBase depending on wpSourceType and initializes it
  97          */
  98         public static function createFromRequest( &$request, $type = null ) {
  99                 $type = $type ? $type : $request->getVal( 'wpSourceType', 'File' );
 100
 101                 if( !$type ) {
 102                         return null;
 103                 }
 104
 105                 // Get the upload class
 106                 $type = ucfirst( $type );
 107
 108                 // Give hooks the chance to handle this request
 109                 $className = null;
 110                 wfRunHooks( 'UploadCreateFromRequest', array( $type, &$className ) );
 111                 if ( is_null( $className ) ) {
 112                         $className = 'UploadFrom' . $type;
 113                         wfDebug( __METHOD__ . ": class name: $className\n" );
 114                         if( !in_array( $type, self::$uploadHandlers ) ) {
 115                                 return null;
 116                         }
 117                 }
 118
 119                 // Check whether this upload class is enabled
 120                 if( !call_user_func( array( $className, 'isEnabled' ) ) ) {
 121                         return null;
 122                 }
 123
 124                 // Check whether the request is valid
 125                 if( !call_user_func( array( $className, 'isValidRequest' ), $request ) ) {
 126                         return null;
 127                 }
 128
 129                 $handler = new $className;
 130
 131                 $handler->initializeFromRequest( $request );
 132                 return $handler;
 133         }
 134
 135         /**
 136          * Check whether a request if valid for this handler
 137          */
 138         public static function isValidRequest( $request ) {
 139                 return false;
 140         }
 141
 142         public function __construct() {}
 143
 144         /**
 145          * Initialize the path information
 146          * @param $name string the desired destination name
 147          * @param $tempPath string the temporary path
 148          * @param $fileSize int the file size
 149          * @param $removeTempFile bool (false) remove the temporary file?
 150          * @return null
 151          */
 152         public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
 153                 $this->mDesiredDestName = $name;
 154                 $this->mTempPath = $tempPath;
 155                 $this->mFileSize = $fileSize;
 156                 $this->mRemoveTempFile = $removeTempFile;
 157         }
 158
 159         /**
 160          * Initialize from a WebRequest. Override this in a subclass.
 161          */
 162         public abstract function initializeFromRequest( &$request );
 163
 164         /**
 165          * Fetch the file. Usually a no-op
 166          */
 167         public function fetchFile() {
 168                 return Status::newGood();
 169         }
 170
 171         /**
 172          * Return true if the file is empty
 173          * @return bool
 174          */
 175         public function isEmptyFile() {
 176                 return empty( $this->mFileSize );
 177         }
 178
 179         /**
 180          * Return the file size
 181          * @return integer
 182          */
 183         public function getFileSize() {
 184                 return $this->mFileSize;
 185         }
 186
 187         /**
 188          * Append a file to the Repo file
 189          *
 190          * @param $srcPath String: path to source file
 191          * @param $toAppendPath String: path to the Repo file that will be appended to.
 192          * @return Status Status
 193          */
 194         protected function appendToUploadFile( $srcPath, $toAppendPath ) {
 195                 $repo = RepoGroup::singleton()->getLocalRepo();
 196                 $status = $repo->append( $srcPath, $toAppendPath );
 197                 return $status;
 198         }
 199
 200         /**
 201          * @param $srcPath String: the source path
 202          * @return the real path if it was a virtual URL
 203          */
 204         function getRealPath( $srcPath ) {
 205                 $repo = RepoGroup::singleton()->getLocalRepo();
 206                 if ( $repo->isVirtualUrl( $srcPath ) ) {
 207                         return $repo->resolveVirtualUrl( $srcPath );
 208                 }
 209                 return $srcPath;
 210         }
 211
 212         /**
 213          * Verify whether the upload is sane.
 214          * @return mixed self::OK or else an array with error information
 215          */
 216         public function verifyUpload( ) {
 217                 /**
 218                  * If there was no filename or a zero size given, give up quick.
 219                  */
 220                 if( $this->isEmptyFile() ) {
 221                         return array( 'status' => self::EMPTY_FILE );
 222                 }
 223
 224                 /**
 225                  * Honor $wgMaxUploadSize
 226                  */
 227                 global $wgMaxUploadSize;
 228                 if( $this->mFileSize > $wgMaxUploadSize ) {
 229                         return array( 'status' => self::FILE_TOO_LARGE );
 230                 }
 231
 232                 /**
 233                  * Look at the contents of the file; if we can recognize the
 234                  * type but it's corrupt or data of the wrong type, we should
 235                  * probably not accept it.
 236                  */
 237                 $verification = $this->verifyFile();
 238                 if( $verification !== true ) {
 239                         return array(
 240                                 'status' => self::VERIFICATION_ERROR,
 241                                 'details' => $verification
 242                         );
 243                 }
 244
 245                 /**
 246                  * Make sure this file can be created
 247                  */
 248                 $result = $this->validateNameAndOverwrite();
 249                 if( $result !== true ) {
 250                         return $result;
 251                 }
 252
 253                 $error = '';
 254                 if( !wfRunHooks( 'UploadVerification',
 255                                 array( $this->mDestName, $this->mTempPath, &$error ) ) ) {
 256                         // @fixme This status needs another name...
 257                         return array( 'status' => self::HOOK_ABORTED, 'error' => $error );
 258                 }
 259
 260                 return array( 'status' => self::OK );
 261         }
 262
 263         /**
 264          * Verify that the name is valid and, if necessary, that we can overwrite
 265          *
 266          * @return mixed true if valid, otherwise and array with 'status'
 267          * and other keys
 268          **/
 269         public function validateNameAndOverwrite() {
 270                 $nt = $this->getTitle();
 271                 if( is_null( $nt ) ) {
 272                         $result = array( 'status' => $this->mTitleError );
 273                         if( $this->mTitleError == self::ILLEGAL_FILENAME ) {
 274                                 $result['filtered'] = $this->mFilteredName;
 275                         }
 276                         if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
 277                                 $result['finalExt'] = $this->mFinalExtension;
 278                         }
 279                         return $result;
 280                 }
 281                 $this->mDestName = $this->getLocalFile()->getName();
 282
 283                 /**
 284                  * In some cases we may forbid overwriting of existing files.
 285                  */
 286                 $overwrite = $this->checkOverwrite();
 287                 if( $overwrite !== true ) {
 288                         return array(
 289                                 'status' => self::OVERWRITE_EXISTING_FILE,
 290                                 'overwrite' => $overwrite
 291                         );
 292                 }
 293                 return true;
 294         }
 295
 296         /**
 297          * Verify the mime type
 298          * @param $magic MagicMime object
 299          * @param $mime string representing the mime
 300          * @return mixed true if the file is verified, an array otherwise
 301          */
 302         protected function verifyMimeType( $magic, $mime ) {
 303                 global $wgVerifyMimeType;
 304                 if ( $wgVerifyMimeType ) {
 305                         wfDebug ( "\n\nmime: <$mime> extension: <{$this->mFinalExtension}>\n\n");
 306                         if ( !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 307                                 return array( 'filetype-mime-mismatch' );
 308                         }
 309
 310                         global $wgMimeTypeBlacklist;
 311                         if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 312                                 return array( 'filetype-badmime', $mime );
 313                         }
 314
 315                         # Check IE type
 316                         $fp = fopen( $this->mTempPath, 'rb' );
 317                         $chunk = fread( $fp, 256 );
 318                         fclose( $fp );
 319                         $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 320                         $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 321                         foreach ( $ieTypes as $ieType ) {
 322                                 if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 323                                         return array( 'filetype-bad-ie-mime', $ieType );
 324                                 }
 325                         }
 326                 }
 327
 328                 return true;
 329         }
 330
 331         /**
 332          * Verifies that it's ok to include the uploaded file
 333          *
 334          * @return mixed true of the file is verified, array otherwise.
 335          */
 336         protected function verifyFile() {
 337                 $this->mFileProps = File::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 338                 $this->checkMacBinary();
 339
 340                 # magically determine mime type
 341                 $magic = MimeMagic::singleton();
 342                 $mime = $magic->guessMimeType( $this->mTempPath, false );
 343
 344                 # check mime type, if desired
 345                 $status = $this->verifyMimeType( $magic, $mime );
 346                 if ( $status !== true ) {
 347                         return $status;
 348                 }
 349
 350                 # check for htmlish code and javascript
 351                 if( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 352                         return array( 'uploadscripted' );
 353                 }
 354                 if( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 355                         if( self::detectScriptInSvg( $this->mTempPath ) ) {
 356                                 return array( 'uploadscripted' );
 357                         }
 358                 }
 359
 360                 /**
 361                 * Scan the uploaded file for viruses
 362                 */
 363                 $virus = $this->detectVirus( $this->mTempPath );
 364                 if ( $virus ) {
 365                         return array( 'uploadvirus', $virus );
 366                 }
 367                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 368                 return true;
 369         }
 370
 371         /**
 372          * Check whether the user can edit, upload and create the image.
 373          *
 374          * @param $user the User object to verify the permissions against
 375          * @return mixed An array as returned by getUserPermissionsErrors or true
 376          *               in case the user has proper permissions.
 377          */
 378         public function verifyPermissions( $user ) {
 379                 /**
 380                  * If the image is protected, non-sysop users won't be able
 381                  * to modify it by uploading a new revision.
 382                  */
 383                 $nt = $this->getTitle();
 384                 if( is_null( $nt ) ) {
 385                         return true;
 386                 }
 387                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 388                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 389                 $permErrorsCreate = ( $nt->exists() ? array() : $nt->getUserPermissionsErrors( 'create', $user ) );
 390                 if( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 391                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 392                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 393                         return $permErrors;
 394                 }
 395                 return true;
 396         }
 397
 398         /**
 399          * Check for non fatal problems with the file
 400          *
 401          * @return Array of warnings
 402          */
 403         public function checkWarnings() {
 404                 $warnings = array();
 405
 406                 $localFile = $this->getLocalFile();
 407                 $filename = $localFile->getName();
 408                 $n = strrpos( $filename, '.' );
 409                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
 410
 411                 /**
 412                  * Check whether the resulting filename is different from the desired one,
 413                  * but ignore things like ucfirst() and spaces/underscore things
 414                  */
 415                 $comparableName = str_replace( ' ', '_', $this->mDesiredDestName );
 416                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 417
 418                 if( $this->mDesiredDestName != $filename && $comparableName != $filename ) {
 419                         $warnings['badfilename'] = $filename;
 420                 }
 421
 422                 // Check whether the file extension is on the unwanted list
 423                 global $wgCheckFileExtensions, $wgFileExtensions;
 424                 if ( $wgCheckFileExtensions ) {
 425                         if ( !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) {
 426                                 $warnings['filetype-unwanted-type'] = $this->mFinalExtension;
 427                         }
 428                 }
 429
 430                 global $wgUploadSizeWarning;
 431                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) ) {
 432                         $warnings['large-file'] = $wgUploadSizeWarning;
 433                 }
 434
 435                 if ( $this->mFileSize == 0 ) {
 436                         $warnings['emptyfile'] = true;
 437                 }
 438
 439                 $exists = self::getExistsWarning( $localFile );
 440                 if( $exists !== false ) {
 441                         $warnings['exists'] = $exists;
 442                 }
 443
 444                 // Check dupes against existing files
 445                 $hash = File::sha1Base36( $this->mTempPath );
 446                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 447                 $title = $this->getTitle();
 448                 // Remove all matches against self
 449                 foreach ( $dupes as $key => $dupe ) {
 450                         if( $title->equals( $dupe->getTitle() ) ) {
 451                                 unset( $dupes[$key] );
 452                         }
 453                 }
 454                 if( $dupes ) {
 455                         $warnings['duplicate'] = $dupes;
 456                 }
 457
 458                 // Check dupes against archives
 459                 $archivedImage = new ArchivedFile( null, 0, "{$hash}.{$this->mFinalExtension}" );
 460                 if ( $archivedImage->getID() > 0 ) {
 461                         $warnings['duplicate-archive'] = $archivedImage->getName();
 462                 }
 463
 464                 return $warnings;
 465         }
 466
 467         /**
 468          * Really perform the upload. Stores the file in the local repo, watches
 469          * if necessary and runs the UploadComplete hook.
 470          *
 471          * @return mixed Status indicating the whether the upload succeeded.
 472          */
 473         public function performUpload( $comment, $pageText, $watch, $user ) {
 474                 wfDebug( "\n\n\performUpload: sum: " . $comment . ' c: ' . $pageText .
 475                         ' w: ' . $watch );
 476                 $status = $this->getLocalFile()->upload( $this->mTempPath, $comment, $pageText,
 477                         File::DELETE_SOURCE, $this->mFileProps, false, $user );
 478
 479                 if( $status->isGood() ) {
 480                         if ( $watch ) {
 481                                 $user->addWatch( $this->getLocalFile()->getTitle() );
 482                         }
 483
 484                         wfRunHooks( 'UploadComplete', array( &$this ) );
 485                 }
 486
 487                 return $status;
 488         }
 489
 490         /**
 491          * Returns the title of the file to be uploaded. Sets mTitleError in case
 492          * the name was illegal.
 493          *
 494          * @return Title The title of the file or null in case the name was illegal
 495          */
 496         public function getTitle() {
 497                 if ( $this->mTitle !== false ) {
 498                         return $this->mTitle;
 499                 }
 500
 501                 /**
 502                  * Chop off any directories in the given filename. Then
 503                  * filter out illegal characters, and try to make a legible name
 504                  * out of it. We'll strip some silently that Title would die on.
 505                  */
 506                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mDesiredDestName );
 507                 /* Normalize to title form before we do any further processing */
 508                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 509                 if( is_null( $nt ) ) {
 510                         $this->mTitleError = self::ILLEGAL_FILENAME;
 511                         return $this->mTitle = null;
 512                 }
 513                 $this->mFilteredName = $nt->getDBkey();
 514
 515                 /**
 516                  * We'll want to blacklist against *any* 'extension', and use
 517                  * only the final one for the whitelist.
 518                  */
 519                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 520
 521                 if( count( $ext ) ) {
 522                         $this->mFinalExtension = trim( $ext[count( $ext ) - 1] );
 523                 } else {
 524                         $this->mFinalExtension = '';
 525                 }
 526
 527                 /* Don't allow users to override the blacklist (check file extension) */
 528                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 529                 global $wgFileExtensions, $wgFileBlacklist;
 530                 if ( $this->mFinalExtension == '' ) {
 531                         $this->mTitleError = self::FILETYPE_MISSING;
 532                         return $this->mTitle = null;
 533                 } elseif ( $this->checkFileExtensionList( $ext, $wgFileBlacklist ) ||
 534                                 ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 535                                         !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) ) {
 536                         $this->mTitleError = self::FILETYPE_BADTYPE;
 537                         return $this->mTitle = null;
 538                 }
 539
 540                 # If there was more than one "extension", reassemble the base
 541                 # filename to prevent bogus complaints about length
 542                 if( count( $ext ) > 1 ) {
 543                         for( $i = 0; $i < count( $ext ) - 1; $i++ ) {
 544                                 $partname .= '.' . $ext[$i];
 545                         }
 546                 }
 547
 548                 if( strlen( $partname ) < 1 ) {
 549                         $this->mTitleError =  self::MIN_LENGTH_PARTNAME;
 550                         return $this->mTitle = null;
 551                 }
 552
 553                 return $this->mTitle = $nt;
 554         }
 555
 556         /**
 557          * Return the local file and initializes if necessary.
 558          */
 559         public function getLocalFile() {
 560                 if( is_null( $this->mLocalFile ) ) {
 561                         $nt = $this->getTitle();
 562                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 563                 }
 564                 return $this->mLocalFile;
 565         }
 566
 567         /**
 568          * Stash a file in a temporary directory for later processing
 569          * after the user has confirmed it.
 570          *
 571          * If the user doesn't explicitly cancel or accept, these files
 572          * can accumulate in the temp directory.
 573          *
 574          * @param $saveName String: the destination filename
 575          * @param $tempSrc String: the source temporary file to save
 576          * @return String: full path the stashed file, or false on failure
 577          */
 578         protected function saveTempUploadedFile( $saveName, $tempSrc ) {
 579                 $repo = RepoGroup::singleton()->getLocalRepo();
 580                 $status = $repo->storeTemp( $saveName, $tempSrc );
 581                 return $status;
 582         }
 583
 584         /**
 585          * Stash a file in a temporary directory for later processing,
 586          * and save the necessary descriptive info into the session.
 587          * Returns a key value which will be passed through a form
 588          * to pick up the path info on a later invocation.
 589          *
 590          * @return Integer: session key
 591          */
 592         public function stashSession() {
 593                 $status = $this->saveTempUploadedFile( $this->mDestName, $this->mTempPath );
 594                 if( !$status->isOK() ) {
 595                         # Couldn't save the file.
 596                         return false;
 597                 }
 598
 599                 $key = $this->getSessionKey();
 600                 $_SESSION[self::SESSION_KEYNAME][$key] = array(
 601                         'mTempPath'       => $status->value,
 602                         'mFileSize'       => $this->mFileSize,
 603                         'mFileProps'      => $this->mFileProps,
 604                         'version'         => self::SESSION_VERSION,
 605                 );
 606                 return $key;
 607         }
 608
 609         /**
 610          * Generate a random session key from stash in cases where we want
 611          * to start an upload without much information
 612          */
 613         protected function getSessionKey() {
 614                 $key = mt_rand( 0, 0x7fffffff );
 615                 $_SESSION[self::SESSION_KEYNAME][$key] = array();
 616                 return $key;
 617         }
 618
 619         /**
 620          * If we've modified the upload file we need to manually remove it
 621          * on exit to clean up.
 622          */
 623         public function cleanupTempFile() {
 624                 if ( $this->mRemoveTempFile && $this->mTempPath && file_exists( $this->mTempPath ) ) {
 625                         wfDebug( __METHOD__ . ": Removing temporary file {$this->mTempPath}\n" );
 626                         unlink( $this->mTempPath );
 627                 }
 628         }
 629
 630         public function getTempPath() {
 631                 return $this->mTempPath;
 632         }
 633
 634         /**
 635          * Split a file into a base name and all dot-delimited 'extensions'
 636          * on the end. Some web server configurations will fall back to
 637          * earlier pseudo-'extensions' to determine type and execute
 638          * scripts, so the blacklist needs to check them all.
 639          *
 640          * @return array
 641          */
 642         public static function splitExtensions( $filename ) {
 643                 $bits = explode( '.', $filename );
 644                 $basename = array_shift( $bits );
 645                 return array( $basename, $bits );
 646         }
 647
 648         /**
 649          * Perform case-insensitive match against a list of file extensions.
 650          * Returns true if the extension is in the list.
 651          *
 652          * @param $ext String
 653          * @param $list Array
 654          * @return Boolean
 655          */
 656         public static function checkFileExtension( $ext, $list ) {
 657                 return in_array( strtolower( $ext ), $list );
 658         }
 659
 660         /**
 661          * Perform case-insensitive match against a list of file extensions.
 662          * Returns true if any of the extensions are in the list.
 663          *
 664          * @param $ext Array
 665          * @param $list Array
 666          * @return Boolean
 667          */
 668         public static function checkFileExtensionList( $ext, $list ) {
 669                 foreach( $ext as $e ) {
 670                         if( in_array( strtolower( $e ), $list ) ) {
 671                                 return true;
 672                         }
 673                 }
 674                 return false;
 675         }
 676
 677         /**
 678          * Checks if the mime type of the uploaded file matches the file extension.
 679          *
 680          * @param $mime String: the mime type of the uploaded file
 681          * @param $extension String: the filename extension that the file is to be served with
 682          * @return Boolean
 683          */
 684         public static function verifyExtension( $mime, $extension ) {
 685                 $magic = MimeMagic::singleton();
 686
 687                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' )
 688                         if ( !$magic->isRecognizableExtension( $extension ) ) {
 689                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
 690                                         "unrecognized extension '$extension', can't verify\n" );
 691                                 return true;
 692                         } else {
 693                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; ".
 694                                         "recognized extension '$extension', so probably invalid file\n" );
 695                                 return false;
 696                         }
 697
 698                 $match = $magic->isMatchingExtension( $extension, $mime );
 699
 700                 if ( $match === null ) {
 701                         wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
 702                         return true;
 703                 } elseif( $match === true ) {
 704                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
 705
 706                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 707                         return true;
 708
 709                 } else {
 710                         wfDebug( __METHOD__ . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
 711                         return false;
 712                 }
 713         }
 714
 715         /**
 716          * Heuristic for detecting files that *could* contain JavaScript instructions or
 717          * things that may look like HTML to a browser and are thus
 718          * potentially harmful. The present implementation will produce false
 719          * positives in some situations.
 720          *
 721          * @param $file String: pathname to the temporary upload file
 722          * @param $mime String: the mime type of the file
 723          * @param $extension String: the extension of the file
 724          * @return Boolean: true if the file contains something looking like embedded scripts
 725          */
 726         public static function detectScript( $file, $mime, $extension ) {
 727                 global $wgAllowTitlesInSVG;
 728
 729                 # ugly hack: for text files, always look at the entire file.
 730                 # For binary field, just check the first K.
 731
 732                 if( strpos( $mime,'text/' ) === 0 ) {
 733                         $chunk = file_get_contents( $file );
 734                 } else {
 735                         $fp = fopen( $file, 'rb' );
 736                         $chunk = fread( $fp, 1024 );
 737                         fclose( $fp );
 738                 }
 739
 740                 $chunk = strtolower( $chunk );
 741
 742                 if( !$chunk ) {
 743                         return false;
 744                 }
 745
 746                 # decode from UTF-16 if needed (could be used for obfuscation).
 747                 if( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
 748                         $enc = 'UTF-16BE';
 749                 } elseif( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
 750                         $enc = 'UTF-16LE';
 751                 } else {
 752                         $enc = null;
 753                 }
 754
 755                 if( $enc ) {
 756                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
 757                 }
 758
 759                 $chunk = trim( $chunk );
 760
 761                 # FIXME: convert from UTF-16 if necessarry!
 762                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
 763
 764                 # check for HTML doctype
 765                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
 766                         return true;
 767                 }
 768
 769                 /**
 770                  * Internet Explorer for Windows performs some really stupid file type
 771                  * autodetection which can cause it to interpret valid image files as HTML
 772                  * and potentially execute JavaScript, creating a cross-site scripting
 773                  * attack vectors.
 774                  *
 775                  * Apple's Safari browser also performs some unsafe file type autodetection
 776                  * which can cause legitimate files to be interpreted as HTML if the
 777                  * web server is not correctly configured to send the right content-type
 778                  * (or if you're really uploading plain text and octet streams!)
 779                  *
 780                  * Returns true if IE is likely to mistake the given file for HTML.
 781                  * Also returns true if Safari would mistake the given file for HTML
 782                  * when served with a generic content-type.
 783                  */
 784                 $tags = array(
 785                         '<a href',
 786                         '<body',
 787                         '<head',
 788                         '<html',   #also in safari
 789                         '<img',
 790                         '<pre',
 791                         '<script', #also in safari
 792                         '<table'
 793                 );
 794
 795                 if( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
 796                         $tags[] = '<title';
 797                 }
 798
 799                 foreach( $tags as $tag ) {
 800                         if( false !== strpos( $chunk, $tag ) ) {
 801                                 return true;
 802                         }
 803                 }
 804
 805                 /*
 806                  * look for JavaScript
 807                  */
 808
 809                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
 810                 $chunk = Sanitizer::decodeCharReferences( $chunk );
 811
 812                 # look for script-types
 813                 if( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
 814                         return true;
 815                 }
 816
 817                 # look for html-style script-urls
 818                 if( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
 819                         return true;
 820                 }
 821
 822                 # look for css-style script-urls
 823                 if( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
 824                         return true;
 825                 }
 826
 827                 wfDebug( __METHOD__ . ": no scripts found\n" );
 828                 return false;
 829         }
 830
 831         protected function detectScriptInSvg( $filename ) {
 832                 $check = new XmlTypeCheck( $filename, array( $this, 'checkSvgScriptCallback' ) );
 833                 return $check->filterMatch;
 834         }
 835
 836         /**
 837          * @todo Replace this with a whitelist filter!
 838          */
 839         public function checkSvgScriptCallback( $element, $attribs ) {
 840                 $stripped = $this->stripXmlNamespace( $element );
 841
 842                 if( $stripped == 'script' ) {
 843                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
 844                         return true;
 845                 }
 846
 847                 foreach( $attribs as $attrib => $value ) {
 848                         $stripped = $this->stripXmlNamespace( $attrib );
 849                         if( substr( $stripped, 0, 2 ) == 'on' ) {
 850                                 wfDebug( __METHOD__ . ": Found script attribute '$attrib'='value' in uploaded file.\n" );
 851                                 return true;
 852                         }
 853                         if( $stripped == 'href' && strpos( strtolower( $value ), 'javascript:' ) !== false ) {
 854                                 wfDebug( __METHOD__ . ": Found script href attribute '$attrib'='$value' in uploaded file.\n" );
 855                                 return true;
 856                         }
 857                 }
 858         }
 859
 860         private function stripXmlNamespace( $name ) {
 861                 // 'http://www.w3.org/2000/svg:script' -> 'script'
 862                 $parts = explode( ':', strtolower( $name ) );
 863                 return array_pop( $parts );
 864         }
 865
 866         /**
 867          * Generic wrapper function for a virus scanner program.
 868          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
 869          * $wgAntivirusRequired may be used to deny upload if the scan fails.
 870          *
 871          * @param $file String: pathname to the temporary upload file
 872          * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
 873          *         or a string containing feedback from the virus scanner if a virus was found.
 874          *         If textual feedback is missing but a virus was found, this function returns true.
 875          */
 876         public static function detectVirus( $file ) {
 877                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
 878
 879                 if ( !$wgAntivirus ) {
 880                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
 881                         return null;
 882                 }
 883
 884                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
 885                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
 886                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1</div>",
 887                                 array( 'virus-badscanner', $wgAntivirus ) );
 888                         return wfMsg( 'virus-unknownscanner' ) . " $wgAntivirus";
 889                 }
 890
 891                 # look up scanner configuration
 892                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
 893                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
 894                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ) ?
 895                         $wgAntivirusSetup[$wgAntivirus]['messagepattern'] : null;
 896
 897                 if ( strpos( $command, "%f" ) === false ) {
 898                         # simple pattern: append file to scan
 899                         $command .= " " . wfEscapeShellArg( $file );
 900                 } else {
 901                         # complex pattern: replace "%f" with file to scan
 902                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
 903                 }
 904
 905                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
 906
 907                 # execute virus scanner
 908                 $exitCode = false;
 909
 910                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
 911                 #      that does not seem to be worth the pain.
 912                 #      Ask me (Duesentrieb) about it if it's ever needed.
 913                 $output = wfShellExec( "$command 2>&1", $exitCode );
 914
 915                 # map exit code to AV_xxx constants.
 916                 $mappedCode = $exitCode;
 917                 if ( $exitCodeMap ) {
 918                         if ( isset( $exitCodeMap[$exitCode] ) ) {
 919                                 $mappedCode = $exitCodeMap[$exitCode];
 920                         } elseif ( isset( $exitCodeMap["*"] ) ) {
 921                                 $mappedCode = $exitCodeMap["*"];
 922                         }
 923                 }
 924
 925                 if ( $mappedCode === AV_SCAN_FAILED ) {
 926                         # scan failed (code was mapped to false by $exitCodeMap)
 927                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
 928
 929                         if ( $wgAntivirusRequired ) {
 930                                 return wfMsg( 'virus-scanfailed', array( $exitCode ) );
 931                         } else {
 932                                 return null;
 933                         }
 934                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
 935                         # scan failed because filetype is unknown (probably imune)
 936                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
 937                         return null;
 938                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
 939                         # no virus found
 940                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
 941                         return false;
 942                 } else {
 943                         $output = trim( $output );
 944
 945                         if ( !$output ) {
 946                                 $output = true; #if there's no output, return true
 947                         } elseif ( $msgPattern ) {
 948                                 $groups = array();
 949                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
 950                                         if ( $groups[1] ) {
 951                                                 $output = $groups[1];
 952                                         }
 953                                 }
 954                         }
 955
 956                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
 957                         return $output;
 958                 }
 959         }
 960
 961         /**
 962          * Check if the temporary file is MacBinary-encoded, as some uploads
 963          * from Internet Explorer on Mac OS Classic and Mac OS X will be.
 964          * If so, the data fork will be extracted to a second temporary file,
 965          * which will then be checked for validity and either kept or discarded.
 966          */
 967         private function checkMacBinary() {
 968                 $macbin = new MacBinary( $this->mTempPath );
 969                 if( $macbin->isValid() ) {
 970                         $dataFile = tempnam( wfTempDir(), 'WikiMacBinary' );
 971                         $dataHandle = fopen( $dataFile, 'wb' );
 972
 973                         wfDebug( __METHOD__ . ": Extracting MacBinary data fork to $dataFile\n" );
 974                         $macbin->extractData( $dataHandle );
 975
 976                         $this->mTempPath = $dataFile;
 977                         $this->mFileSize = $macbin->dataForkLength();
 978
 979                         // We'll have to manually remove the new file if it's not kept.
 980                         $this->mRemoveTempFile = true;
 981                 }
 982                 $macbin->close();
 983         }
 984
 985         /**
 986          * Check if there's an overwrite conflict and, if so, if restrictions
 987          * forbid this user from performing the upload.
 988          *
 989          * @return mixed true on success, error string on failure
 990          */
 991         private function checkOverwrite() {
 992                 global $wgUser;
 993                 // First check whether the local file can be overwritten
 994                 $file = $this->getLocalFile();
 995                 if( $file->exists() ) {
 996                         if( !self::userCanReUpload( $wgUser, $file ) ) {
 997                                 return 'fileexists-forbidden';
 998                         } else {
 999                                 return true;
1000                         }
1001                 }
1002
1003                 /* Check shared conflicts: if the local file does not exist, but
1004                  * wfFindFile finds a file, it exists in a shared repository.
1005                  */
1006                 $file = wfFindFile( $this->getTitle() );
1007                 if ( $file && !$wgUser->isAllowed( 'reupload-shared' ) ) {
1008                         return 'fileexists-shared-forbidden';
1009                 }
1010
1011                 return true;
1012         }
1013
1014         /**
1015          * Check if a user is the last uploader
1016          *
1017          * @param $user User object
1018          * @param $img String: image name
1019          * @return Boolean
1020          */
1021         public static function userCanReUpload( User $user, $img ) {
1022                 if( $user->isAllowed( 'reupload' ) ) {
1023                         return true; // non-conditional
1024                 }
1025                 if( !$user->isAllowed( 'reupload-own' ) ) {
1026                         return false;
1027                 }
1028                 if( is_string( $img ) ) {
1029                         $img = wfLocalFile( $img );
1030                 }
1031                 if ( !( $img instanceof LocalFile ) ) {
1032                         return false;
1033                 }
1034
1035                 return $user->getId() == $img->getUser( 'id' );
1036         }
1037
1038         /**
1039          * Helper function that does various existence checks for a file.
1040          * The following checks are performed:
1041          * - The file exists
1042          * - Article with the same name as the file exists
1043          * - File exists with normalized extension
1044          * - The file looks like a thumbnail and the original exists
1045          *
1046          * @param $file The File object to check
1047          * @return mixed False if the file does not exists, else an array
1048          */
1049         public static function getExistsWarning( $file ) {
1050                 if( $file->exists() ) {
1051                         return array( 'warning' => 'exists', 'file' => $file );
1052                 }
1053
1054                 if( $file->getTitle()->getArticleID() ) {
1055                         return array( 'warning' => 'page-exists', 'file' => $file );
1056                 }
1057
1058                 if ( $file->wasDeleted() && !$file->exists() ) {
1059                         return array( 'warning' => 'was-deleted', 'file' => $file );
1060                 }
1061
1062                 if( strpos( $file->getName(), '.' ) == false ) {
1063                         $partname = $file->getName();
1064                         $extension = '';
1065                 } else {
1066                         $n = strrpos( $file->getName(), '.' );
1067                         $extension = substr( $file->getName(), $n + 1 );
1068                         $partname = substr( $file->getName(), 0, $n );
1069                 }
1070                 $normalizedExtension = File::normalizeExtension( $extension );
1071
1072                 if ( $normalizedExtension != $extension ) {
1073                         // We're not using the normalized form of the extension.
1074                         // Normal form is lowercase, using most common of alternate
1075                         // extensions (eg 'jpg' rather than 'JPEG').
1076                         //
1077                         // Check for another file using the normalized form...
1078                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
1079                         $file_lc = wfLocalFile( $nt_lc );
1080
1081                         if( $file_lc->exists() ) {
1082                                 return array(
1083                                         'warning' => 'exists-normalized',
1084                                         'file' => $file,
1085                                         'normalizedFile' => $file_lc
1086                                 );
1087                         }
1088                 }
1089
1090                 if ( self::isThumbName( $file->getName() ) ) {
1091                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
1092                         $nt_thb = Title::newFromText( substr( $partname , strpos( $partname , '-' ) +1 ) . '.' . $extension, NS_FILE );
1093                         $file_thb = wfLocalFile( $nt_thb );
1094                         if( $file_thb->exists() ) {
1095                                 return array(
1096                                         'warning' => 'thumb',
1097                                         'file' => $file,
1098                                         'thumbFile' => $file_thb
1099                                 );
1100                         } else {
1101                                 // File does not exist, but we just don't like the name
1102                                 return array(
1103                                         'warning' => 'thumb-name',
1104                                         'file' => $file,
1105                                         'thumbFile' => $file_thb
1106                                 );
1107                         }
1108                 }
1109
1110
1111                 foreach( self::getFilenamePrefixBlacklist() as $prefix ) {
1112                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
1113                                 return array(
1114                                         'warning' => 'bad-prefix',
1115                                         'file' => $file,
1116                                         'prefix' => $prefix
1117                                 );
1118                         }
1119                 }
1120
1121                 return false;
1122         }
1123
1124         /**
1125          * Helper function that checks whether the filename looks like a thumbnail
1126          */
1127         public static function isThumbName( $filename ) {
1128                 $n = strrpos( $filename, '.' );
1129                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
1130                 return (
1131                                         substr( $partname , 3, 3 ) == 'px-' ||
1132                                         substr( $partname , 2, 3 ) == 'px-'
1133                                 ) &&
1134                                 preg_match( "/[0-9]{2}/" , substr( $partname , 0, 2 ) );
1135         }
1136
1137         /**
1138          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
1139          *
1140          * @return array list of prefixes
1141          */
1142         public static function getFilenamePrefixBlacklist() {
1143                 $blacklist = array();
1144                 $message = wfMsgForContent( 'filename-prefix-blacklist' );
1145                 if( $message && !( wfEmptyMsg( 'filename-prefix-blacklist', $message ) || $message == '-' ) ) {
1146                         $lines = explode( "\n", $message );
1147                         foreach( $lines as $line ) {
1148                                 // Remove comment lines
1149                                 $comment = substr( trim( $line ), 0, 1 );
1150                                 if ( $comment == '#' || $comment == '' ) {
1151                                         continue;
1152                                 }
1153                                 // Remove additional comments after a prefix
1154                                 $comment = strpos( $line, '#' );
1155                                 if ( $comment > 0 ) {
1156                                         $line = substr( $line, 0, $comment-1 );
1157                                 }
1158                                 $blacklist[] = trim( $line );
1159                         }
1160                 }
1161                 return $blacklist;
1162         }
1163
1164         public function getImageInfo( $result ) {
1165                 $file = $this->getLocalFile();
1166                 $imParam = ApiQueryImageInfo::getPropertyNames();
1167                 return ApiQueryImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1168         }
1169
1170         public function convertVerifyErrorToStatus( $error ) {
1171                 $args = func_get_args();
1172                 array_shift($args);
1173                 return Status::newFatal( $this->getVerificationErrorCode( $error ), $args );
1174         }
1175 }