includes/UploadBase.php

   1 <?php
   2
   3 class UploadBase {
   4         var $mTempPath;
   5         var $mDesiredDestName, $mDestName, $mRemoveTempFile, $mSourceType;
   6         var $mTitle = false, $mTitleError = 0;
   7         var $mFilteredName, $mFinalExtension;
   8
   9         const SUCCESS = 0;
  10         const OK = 0;
  11         const BEFORE_PROCESSING = 1;
  12         const LARGE_FILE_SERVER = 2;
  13         const EMPTY_FILE = 3;
  14         const MIN_LENGTH_PARTNAME = 4;
  15         const ILLEGAL_FILENAME = 5;
  16         const PROTECTED_PAGE = 6;
  17         const OVERWRITE_EXISTING_FILE = 7;
  18         const FILETYPE_MISSING = 8;
  19         const FILETYPE_BADTYPE = 9;
  20         const VERIFICATION_ERROR = 10;
  21         const UPLOAD_VERIFICATION_ERROR = 11;
  22         const UPLOAD_WARNING = 12;
  23         const INTERNAL_ERROR = 13;
  24
  25         const SESSION_VERSION = 2;
  26
  27         /**
  28          * Returns true if uploads are enabled.
  29          * Can be overriden by subclasses.
  30          */
  31         static function isEnabled() {
  32                 global $wgEnableUploads;
  33                 return $wgEnableUploads;
  34         }
  35         /**
  36          * Returns true if the user can use this upload module or else a string
  37          * identifying the missing permission.
  38          * Can be overriden by subclasses.
  39          */
  40         static function isAllowed( $user ) {
  41                 if( !$user->isAllowed( 'upload' ) )
  42                         return 'upload';
  43                 return true;
  44         }
  45
  46         // Upload handlers. Should probably just be a global
  47         static $uploadHandlers = array( 'Stash', 'Upload', 'Url' );
  48         /**
  49          * Create a form of UploadBase depending on wpSourceType and initializes it
  50          */
  51         static function createFromRequest( &$request, $type = null ) {
  52                 $type = $type ? $type : $request->getVal( 'wpSourceType' );
  53                 if( !$type )
  54                         return null;
  55                 $type = ucfirst($type);
  56                 $className = 'UploadFrom'.$type;
  57                 if( !in_array( $type, self::$uploadHandlers ) )
  58                         return null;
  59                 if( !call_user_func( array( $className, 'isEnabled' ) ) )
  60                         return null;
  61                 if( !call_user_func( array( $className, 'isValidRequest' ), $request ) )
  62                         return null;
  63
  64                 $handler = new $className;
  65                 $handler->initializeFromRequest( $request );
  66                 return $handler;
  67         }
  68
  69         /**
  70          * Check whether a request if valid for this handler
  71          */
  72         static function isValidRequest( $request ) {
  73                 return false;
  74         }
  75
  76         function __construct() {}
  77
  78         /**
  79          * Do the real variable initialization
  80          */
  81         function initialize( $name, $tempPath, $fileSize, $removeTempFile = false ) {
  82                 $this->mDesiredDestName = $name;
  83                 $this->mTempPath = $tempPath;
  84                 $this->mFileSize = $fileSize;
  85                 $this->mRemoveTempFile = $removeTempFile;
  86         }
  87
  88         /**
  89          * Fetch the file. Usually a no-op
  90          */
  91         function fetchFile() {
  92                 return self::OK;
  93         }
  94
  95         /**
  96          * Verify whether the upload is sane.
  97          * Returns self::OK or else an array with error information
  98          */
  99         function verifyUpload() {
 100                 global $wgUser;
 101
 102                 /**
 103                  * If there was no filename or a zero size given, give up quick.
 104                  */
 105                 if( empty( $this->mFileSize ) )
 106                         return array( 'status' => self::EMPTY_FILE );
 107
 108                 $nt = $this->getTitle();
 109                 if( is_null( $nt ) ) {
 110                         $result = array( 'status' => $this->mTitleError );
 111                         if( $this->mTitleError == self::ILLEGAL_FILENAME )
 112                                 $resul['filtered'] = $this->mFilteredName;
 113                         if ( $this->mTitleError == self::FILETYPE_BADTYPE )
 114                                 $result['finalExt'] = $this->mFinalExtension;
 115                         return $result;
 116                 }
 117                 $this->mLocalFile = wfLocalFile( $nt );
 118                 $this->mDestName = $this->mLocalFile->getName();
 119
 120                 /**
 121                  * In some cases we may forbid overwriting of existing files.
 122                  */
 123                 $overwrite = $this->checkOverwrite( $this->mDestName );
 124                 if( $overwrite !== true )
 125                         return array( 'status' => self::OVERWRITE_EXISTING_FILE, 'overwrite' => $overwrite );
 126
 127                 /**
 128                  * Look at the contents of the file; if we can recognize the
 129                  * type but it's corrupt or data of the wrong type, we should
 130                  * probably not accept it.
 131                  */
 132                 $verification = $this->verifyFile( $this->mTempPath );
 133
 134                 if( $verification !== true ) {
 135                         if( !is_array( $verification ) )
 136                                 $verification = array( $verification );
 137                         $verification['status'] = self::VERIFICATION_ERROR;
 138                         return $verification;
 139                 }
 140
 141                 $error = '';
 142                 if( !wfRunHooks( 'UploadVerification',
 143                                 array( $this->mDestName, $this->mTempPath, &$error ) ) ) {
 144                         return array( 'status' => self::UPLOAD_VERIFICATION_ERROR, 'error' => $error );
 145                 }
 146
 147                 return self::OK;
 148         }
 149
 150         /**
 151          * Verifies that it's ok to include the uploaded file
 152          *
 153          * @param string $tmpfile the full path of the temporary file to verify
 154          * @return mixed true of the file is verified, a string or array otherwise.
 155          */
 156         protected function verifyFile( $tmpfile ) {
 157                 $this->mFileProps = File::getPropsFromPath( $this->mTempPath,
 158                 $this->mFinalExtension );
 159                 $this->checkMacBinary();
 160
 161                 #magically determine mime type
 162                 $magic = MimeMagic::singleton();
 163                 $mime = $magic->guessMimeType( $tmpfile, false );
 164
 165                 #check mime type, if desired
 166                 global $wgVerifyMimeType;
 167                 if ( $wgVerifyMimeType ) {
 168
 169                   wfDebug ( "\n\nmime: <$mime> extension: <{$this->mFinalExtension}>\n\n");
 170                         #check mime type against file extension
 171                         if( !self::verifyExtension( $mime, $this->mFinalExtension ) ) {
 172                                 return 'uploadcorrupt';
 173                         }
 174
 175                         #check mime type blacklist
 176                         global $wgMimeTypeBlacklist;
 177                         if( isset($wgMimeTypeBlacklist) && !is_null($wgMimeTypeBlacklist)
 178                                 && $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 179                                 return array( 'filetype-badmime', $mime );
 180                         }
 181                 }
 182
 183                 #check for htmlish code and javascript
 184                 if( $this->detectScript ( $tmpfile, $mime, $this->mFinalExtension ) ) {
 185                         return 'uploadscripted';
 186                 }
 187
 188                 /**
 189                 * Scan the uploaded file for viruses
 190                 */
 191                 $virus = $this->detectVirus($tmpfile);
 192                 if ( $virus ) {
 193                         return array( 'uploadvirus', $virus );
 194                 }
 195
 196                 wfDebug( __METHOD__.": all clear; passing.\n" );
 197                 return true;
 198         }
 199
 200         /**
 201          * Check whether the user can edit, upload and create the image
 202          */
 203         function verifyPermissions( $user ) {
 204                 /**
 205                  * If the image is protected, non-sysop users won't be able
 206                  * to modify it by uploading a new revision.
 207                  */
 208                 $nt = $this->getTitle();
 209                 if( is_null( $nt ) )
 210                         return true;
 211                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 212                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 213                 $permErrorsCreate = ( $nt->exists() ? array() : $nt->getUserPermissionsErrors( 'create', $user ) );
 214                 if( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 215                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 216                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 217                         return $permErrors;
 218                 }
 219                 return true;
 220         }
 221
 222         /**
 223          * Check for non fatal problems with the file
 224          */
 225         function checkWarnings() {
 226                 $warning = array();
 227
 228                 $filename = $this->mLocalFile->getName();
 229                 $n = strrpos( $filename, '.' );
 230                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
 231
 232                 // Check whether the resulting filename is different from the desired one
 233                 if( $this->mDesiredDestName != $filename )
 234                         $warning['badfilename'] = $filename;
 235
 236                 // Check whether the file extension is on the unwanted list
 237                 global $wgCheckFileExtensions, $wgFileExtensions;
 238                 if ( $wgCheckFileExtensions ) {
 239                         if ( !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) )
 240                                 $warning['filetype-unwanted-type'] = $this->mFinalExtension;
 241                 }
 242
 243                 global $wgUploadSizeWarning;
 244                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) )
 245                         $warning['large-file'] = $wgUploadSizeWarning;
 246
 247                 if ( $this->mFileSize == 0 )
 248                         $warning['emptyfile'] = true;
 249
 250                 $exists = self::getExistsWarning( $this->mLocalFile );
 251                 if( $exists !== false )
 252                         $warning['exists'] = $exists;
 253
 254                 // Check whether this may be a thumbnail
 255                 if( $exists !== false && $exists[0] != 'thumb'
 256                                 && self::isThumbName( $this->mLocalFile->getName() ) )
 257                         $warning['file-thumbnail-no'] = substr( $filename , 0,
 258                                 strpos( $nt->getText() , '-' ) +1 );
 259
 260                 $hash = File::sha1Base36( $this->mTempPath );
 261                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 262                 if( $dupes )
 263                         $warning['duplicate'] = $dupes;
 264
 265                 $filenamePrefixBlacklist = self::getFilenamePrefixBlacklist();
 266                 foreach( $filenamePrefixBlacklist as $prefix ) {
 267                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
 268                                 $warning['filename-bad-prefix'] = $prefix;
 269                                 break;
 270                         }
 271                 }
 272
 273                 # If the file existed before and was deleted, warn the user of this
 274                 # Don't bother doing so if the file exists now, however
 275                 if( $this->mLocalFile->wasDeleted() && !$this->mLocalFile->exists() )
 276                         $warning['filewasdeleted'] = $this->mLocalFile->getTitle();
 277
 278                 return $warning;
 279         }
 280
 281         /**
 282          * Really perform the upload.
 283          */
 284         function performUpload( $comment, $pageText, $watch, $user ) {
 285                 $status = $this->mLocalFile->upload( $this->mTempPath, $comment, $pageText,
 286                         File::DELETE_SOURCE, $this->mFileProps, false, $user );
 287
 288                 if( $status->isGood() && $watch ) {
 289                         $user->addWatch( $this->mLocalFile->getTitle() );
 290                 }
 291
 292                 if( $status->isGood() )
 293                         wfRunHooks( 'UploadComplete', array( &$this ) );
 294
 295                 return $status;
 296         }
 297
 298         /**
 299          * Returns a title or null
 300          */
 301         function getTitle() {
 302                 if ( $this->mTitle !== false )
 303                         return $this->mTitle;
 304
 305                 /**
 306                  * Chop off any directories in the given filename. Then
 307                  * filter out illegal characters, and try to make a legible name
 308                  * out of it. We'll strip some silently that Title would die on.
 309                  */
 310
 311                 $basename = $this->mDesiredDestName;
 312
 313                 $this->mFilteredName = wfStripIllegalFilenameChars( $basename );
 314
 315                 /**
 316                  * We'll want to blacklist against *any* 'extension', and use
 317                  * only the final one for the whitelist.
 318                  */
 319                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 320
 321                 if( count( $ext ) ) {
 322                         $this->mFinalExtension = $ext[count( $ext ) - 1];
 323                 } else {
 324                         $this->mFinalExtension = '';
 325                 }
 326
 327                 /* Don't allow users to override the blacklist (check file extension) */
 328                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 329                 global $wgFileExtensions, $wgFileBlacklist;
 330                 if ( $this->mFinalExtension == '' ) {
 331                         $this->mTitleError = self::FILETYPE_MISSING;
 332                         return $this->mTitle = null;
 333                 } elseif ( $this->checkFileExtensionList( $ext, $wgFileBlacklist ) ||
 334                                 ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 335                                         !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) ) {
 336                         $this->mTitleError = self::FILETYPE_BADTYPE;
 337                         return $this->mTitle = null;
 338                 }
 339
 340                 # If there was more than one "extension", reassemble the base
 341                 # filename to prevent bogus complaints about length
 342                 if( count( $ext ) > 1 ) {
 343                         for( $i = 0; $i < count( $ext ) - 1; $i++ )
 344                                 $partname .= '.' . $ext[$i];
 345                 }
 346
 347                 if( strlen( $partname ) < 1 ) {
 348                         $this->mTitleError =  self::MIN_LENGTH_PARTNAME;
 349                         return $this->mTitle = null;
 350                 }
 351
 352                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 353                 if( is_null( $nt ) ) {
 354                         $this->mTitleError = self::ILLEGAL_FILENAME;
 355                         return $this->mTitle = null;
 356                 }
 357                 return $this->mTitle = $nt;
 358         }
 359
 360         function getLocalFile() {
 361                 if( is_null( $this->mLocalFile ) ) {
 362                         $nt = $this->getTitle();
 363                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 364                 }
 365                 return $this->mLocalFile;
 366         }
 367
 368         /**
 369          * Stash a file in a temporary directory for later processing
 370          * after the user has confirmed it.
 371          *
 372          * If the user doesn't explicitly cancel or accept, these files
 373          * can accumulate in the temp directory.
 374          *
 375          * @param string $saveName - the destination filename
 376          * @param string $tempName - the source temporary file to save
 377          * @return string - full path the stashed file, or false on failure
 378          * @access private
 379          */
 380         function saveTempUploadedFile( $saveName, $tempName ) {
 381                 global $wgOut;
 382                 $repo = RepoGroup::singleton()->getLocalRepo();
 383                 $status = $repo->storeTemp( $saveName, $tempName );
 384                 return $status;
 385         }
 386
 387         /**
 388          * Stash a file in a temporary directory for later processing,
 389          * and save the necessary descriptive info into the session.
 390          * Returns a key value which will be passed through a form
 391          * to pick up the path info on a later invocation.
 392          *
 393          * @return int
 394          * @access private
 395          */
 396         function stashSession() {
 397                 $status = $this->saveTempUploadedFile( $this->mDestName, $this->mTempPath );
 398
 399                 if( !$status->isGood() ) {
 400                         # Couldn't save the file.
 401                         return false;
 402                 }
 403
 404                 return array(
 405                         'mTempPath'       => $status->value,
 406                         'mFileSize'       => $this->mFileSize,
 407                         'mFileProps'      => $this->mFileProps,
 408                         'version'         => self::SESSION_VERSION,
 409                 );
 410         }
 411
 412         /**
 413          * Remove a temporarily kept file stashed by saveTempUploadedFile().
 414          * @return success
 415          */
 416         function unsaveUploadedFile() {
 417                 $repo = RepoGroup::singleton()->getLocalRepo();
 418                 $success = $repo->freeTemp( $this->mTempPath );
 419                 return $success;
 420         }
 421
 422         /**
 423          * If we've modified the upload file we need to manually remove it
 424          * on exit to clean up.
 425          * @access private
 426          */
 427         function cleanupTempFile() {
 428                 if ( $this->mRemoveTempFile && file_exists( $this->mTempPath ) ) {
 429                         wfDebug( __METHOD__.": Removing temporary file {$this->mTempPath}\n" );
 430                         unlink( $this->mTempPath );
 431                 }
 432         }
 433
 434         function getTempPath() {
 435                 return $this->mTempPath;
 436         }
 437
 438
 439                 /**
 440          * Split a file into a base name and all dot-delimited 'extensions'
 441          * on the end. Some web server configurations will fall back to
 442          * earlier pseudo-'extensions' to determine type and execute
 443          * scripts, so the blacklist needs to check them all.
 444          *
 445          * @return array
 446          */
 447         function splitExtensions( $filename ) {
 448                 $bits = explode( '.', $filename );
 449                 $basename = array_shift( $bits );
 450                 return array( $basename, $bits );
 451         }
 452
 453         /**
 454          * Perform case-insensitive match against a list of file extensions.
 455          * Returns true if the extension is in the list.
 456          *
 457          * @param string $ext
 458          * @param array $list
 459          * @return bool
 460          */
 461         function checkFileExtension( $ext, $list ) {
 462                 return in_array( strtolower( $ext ), $list );
 463         }
 464
 465         /**
 466          * Perform case-insensitive match against a list of file extensions.
 467          * Returns true if any of the extensions are in the list.
 468          *
 469          * @param array $ext
 470          * @param array $list
 471          * @return bool
 472          */
 473         function checkFileExtensionList( $ext, $list ) {
 474                 foreach( $ext as $e ) {
 475                         if( in_array( strtolower( $e ), $list ) ) {
 476                                 return true;
 477                         }
 478                 }
 479                 return false;
 480         }
 481
 482
 483         /**
 484          * Checks if the mime type of the uploaded file matches the file extension.
 485          *
 486          * @param string $mime the mime type of the uploaded file
 487          * @param string $extension The filename extension that the file is to be served with
 488          * @return bool
 489          */
 490         public static function verifyExtension( $mime, $extension ) {
 491                 $magic = MimeMagic::singleton();
 492
 493                 if ( ! $mime || $mime == 'unknown' || $mime == 'unknown/unknown' )
 494                         if ( ! $magic->isRecognizableExtension( $extension ) ) {
 495                                 wfDebug( __METHOD__.": passing file with unknown detected mime type; " .
 496                                         "unrecognized extension '$extension', can't verify\n" );
 497                                 return true;
 498                         } else {
 499                                 wfDebug( __METHOD__.": rejecting file with unknown detected mime type; ".
 500                                         "recognized extension '$extension', so probably invalid file\n" );
 501                                 return false;
 502                         }
 503
 504                 $match= $magic->isMatchingExtension($extension,$mime);
 505
 506                 if ($match===NULL) {
 507                         wfDebug( __METHOD__.": no file extension known for mime type $mime, passing file\n" );
 508                         return true;
 509                 } elseif ($match===true) {
 510                         wfDebug( __METHOD__.": mime type $mime matches extension $extension, passing file\n" );
 511
 512                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 513                         return true;
 514
 515                 } else {
 516                         wfDebug( __METHOD__.": mime type $mime mismatches file extension $extension, rejecting file\n" );
 517                         return false;
 518                 }
 519         }
 520
 521         /**
 522          * Heuristic for detecting files that *could* contain JavaScript instructions or
 523          * things that may look like HTML to a browser and are thus
 524          * potentially harmful. The present implementation will produce false positives in some situations.
 525          *
 526          * @param string $file Pathname to the temporary upload file
 527          * @param string $mime The mime type of the file
 528          * @param string $extension The extension of the file
 529          * @return bool true if the file contains something looking like embedded scripts
 530          */
 531         function detectScript($file, $mime, $extension) {
 532                 global $wgAllowTitlesInSVG;
 533
 534                 #ugly hack: for text files, always look at the entire file.
 535                 #For binary field, just check the first K.
 536
 537                 if (strpos($mime,'text/')===0) $chunk = file_get_contents( $file );
 538                 else {
 539                         $fp = fopen( $file, 'rb' );
 540                         $chunk = fread( $fp, 1024 );
 541                         fclose( $fp );
 542                 }
 543
 544                 $chunk= strtolower( $chunk );
 545
 546                 if (!$chunk) return false;
 547
 548                 #decode from UTF-16 if needed (could be used for obfuscation).
 549                 if (substr($chunk,0,2)=="\xfe\xff") $enc= "UTF-16BE";
 550                 elseif (substr($chunk,0,2)=="\xff\xfe") $enc= "UTF-16LE";
 551                 else $enc= NULL;
 552
 553                 if ($enc) $chunk= iconv($enc,"ASCII//IGNORE",$chunk);
 554
 555                 $chunk= trim($chunk);
 556
 557                 #FIXME: convert from UTF-16 if necessarry!
 558
 559                 wfDebug("SpecialUpload::detectScript: checking for embedded scripts and HTML stuff\n");
 560
 561                 #check for HTML doctype
 562                 if (eregi("<!DOCTYPE *X?HTML",$chunk)) return true;
 563
 564                 /**
 565                 * Internet Explorer for Windows performs some really stupid file type
 566                 * autodetection which can cause it to interpret valid image files as HTML
 567                 * and potentially execute JavaScript, creating a cross-site scripting
 568                 * attack vectors.
 569                 *
 570                 * Apple's Safari browser also performs some unsafe file type autodetection
 571                 * which can cause legitimate files to be interpreted as HTML if the
 572                 * web server is not correctly configured to send the right content-type
 573                 * (or if you're really uploading plain text and octet streams!)
 574                 *
 575                 * Returns true if IE is likely to mistake the given file for HTML.
 576                 * Also returns true if Safari would mistake the given file for HTML
 577                 * when served with a generic content-type.
 578                 */
 579
 580                 $tags = array(
 581                         '<body',
 582                         '<head',
 583                         '<html',   #also in safari
 584                         '<img',
 585                         '<pre',
 586                         '<script', #also in safari
 587                         '<table'
 588                         );
 589                 if( ! $wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
 590                         $tags[] = '<title';
 591                 }
 592
 593                 foreach( $tags as $tag ) {
 594                         if( false !== strpos( $chunk, $tag ) ) {
 595                                 return true;
 596                         }
 597                 }
 598
 599                 /*
 600                 * look for javascript
 601                 */
 602
 603                 #resolve entity-refs to look at attributes. may be harsh on big files... cache result?
 604                 $chunk = Sanitizer::decodeCharReferences( $chunk );
 605
 606                 #look for script-types
 607                 if (preg_match('!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim',$chunk)) return true;
 608
 609                 #look for html-style script-urls
 610                 if (preg_match('!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim',$chunk)) return true;
 611
 612                 #look for css-style script-urls
 613                 if (preg_match('!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim',$chunk)) return true;
 614
 615                 wfDebug("SpecialUpload::detectScript: no scripts found\n");
 616                 return false;
 617         }
 618
 619         /**
 620          * Generic wrapper function for a virus scanner program.
 621          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
 622          * $wgAntivirusRequired may be used to deny upload if the scan fails.
 623          *
 624          * @param string $file Pathname to the temporary upload file
 625          * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
 626          *         or a string containing feedback from the virus scanner if a virus was found.
 627          *         If textual feedback is missing but a virus was found, this function returns true.
 628          */
 629         function detectVirus($file) {
 630                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
 631
 632                 if ( !$wgAntivirus ) {
 633                         wfDebug( __METHOD__.": virus scanner disabled\n");
 634                         return NULL;
 635                 }
 636
 637                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
 638                         wfDebug( __METHOD__.": unknown virus scanner: $wgAntivirus\n" );
 639                         $wgOut->wrapWikiMsg( '<div class="error">$1</div>', array( 'virus-badscanner', $wgAntivirus ) );
 640                         return wfMsg('virus-unknownscanner') . " $wgAntivirus";
 641                 }
 642
 643                 # look up scanner configuration
 644                 $command = $wgAntivirusSetup[$wgAntivirus]["command"];
 645                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]["codemap"];
 646                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]["messagepattern"] ) ?
 647                         $wgAntivirusSetup[$wgAntivirus]["messagepattern"] : null;
 648
 649                 if ( strpos( $command,"%f" ) === false ) {
 650                         # simple pattern: append file to scan
 651                         $command .= " " . wfEscapeShellArg( $file );
 652                 } else {
 653                         # complex pattern: replace "%f" with file to scan
 654                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
 655                 }
 656
 657                 wfDebug( __METHOD__.": running virus scan: $command \n" );
 658
 659                 # execute virus scanner
 660                 $exitCode = false;
 661
 662                 #NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
 663                 #      that does not seem to be worth the pain.
 664                 #      Ask me (Duesentrieb) about it if it's ever needed.
 665                 $output = array();
 666                 if ( wfIsWindows() ) {
 667                         exec( "$command", $output, $exitCode );
 668                 } else {
 669                         exec( "$command 2>&1", $output, $exitCode );
 670                 }
 671
 672                 # map exit code to AV_xxx constants.
 673                 $mappedCode = $exitCode;
 674                 if ( $exitCodeMap ) {
 675                         if ( isset( $exitCodeMap[$exitCode] ) ) {
 676                                 $mappedCode = $exitCodeMap[$exitCode];
 677                         } elseif ( isset( $exitCodeMap["*"] ) ) {
 678                                 $mappedCode = $exitCodeMap["*"];
 679                         }
 680                 }
 681
 682                 if ( $mappedCode === AV_SCAN_FAILED ) {
 683                         # scan failed (code was mapped to false by $exitCodeMap)
 684                         wfDebug( __METHOD__.": failed to scan $file (code $exitCode).\n" );
 685
 686                         if ( $wgAntivirusRequired ) {
 687                                 return wfMsg('virus-scanfailed', array( $exitCode ) );
 688                         } else {
 689                                 return NULL;
 690                         }
 691                 } else if ( $mappedCode === AV_SCAN_ABORTED ) {
 692                         # scan failed because filetype is unknown (probably imune)
 693                         wfDebug( __METHOD__.": unsupported file type $file (code $exitCode).\n" );
 694                         return NULL;
 695                 } else if ( $mappedCode === AV_NO_VIRUS ) {
 696                         # no virus found
 697                         wfDebug( __METHOD__.": file passed virus scan.\n" );
 698                         return false;
 699                 } else {
 700                         $output = join( "\n", $output );
 701                         $output = trim( $output );
 702
 703                         if ( !$output ) {
 704                                 $output = true; #if there's no output, return true
 705                         } elseif ( $msgPattern ) {
 706                                 $groups = array();
 707                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
 708                                         if ( $groups[1] ) {
 709                                                 $output = $groups[1];
 710                                         }
 711                                 }
 712                         }
 713
 714                         wfDebug( __METHOD__.": FOUND VIRUS! scanner feedback: $output" );
 715                         return $output;
 716                 }
 717         }
 718
 719         /**
 720          * Check if the temporary file is MacBinary-encoded, as some uploads
 721          * from Internet Explorer on Mac OS Classic and Mac OS X will be.
 722          * If so, the data fork will be extracted to a second temporary file,
 723          * which will then be checked for validity and either kept or discarded.
 724          *
 725          * @access private
 726          */
 727         function checkMacBinary() {
 728                 $macbin = new MacBinary( $this->mTempPath );
 729                 if( $macbin->isValid() ) {
 730                         $dataFile = tempnam( wfTempDir(), "WikiMacBinary" );
 731                         $dataHandle = fopen( $dataFile, 'wb' );
 732
 733                         wfDebug( "SpecialUpload::checkMacBinary: Extracting MacBinary data fork to $dataFile\n" );
 734                         $macbin->extractData( $dataHandle );
 735
 736                         $this->mTempPath = $dataFile;
 737                         $this->mFileSize = $macbin->dataForkLength();
 738
 739                         // We'll have to manually remove the new file if it's not kept.
 740                         $this->mRemoveTempFile = true;
 741                 }
 742                 $macbin->close();
 743         }
 744
 745         /**
 746          * Check if there's an overwrite conflict and, if so, if restrictions
 747          * forbid this user from performing the upload.
 748          *
 749          * @return mixed true on success, WikiError on failure
 750          * @access private
 751          */
 752         function checkOverwrite() {
 753                 global $wgUser;
 754                 // First check whether the local file can be overwritten
 755                 if( $this->mLocalFile->exists() )
 756                         if( !self::userCanReUpload( $wgUser, $this->mLocalFile ) )
 757                                 return 'fileexists-forbidden';
 758
 759                 // Check shared conflicts
 760                 $file = wfFindFile( $this->mLocalFile->getName() );
 761                 if ( $file && ( !$wgUser->isAllowed( 'reupload' ) ||
 762                                 !$wgUser->isAllowed( 'reupload-shared' ) ) )
 763                         return 'fileexists-shared-forbidden';
 764
 765                 return true;
 766
 767         }
 768
 769         /**
 770          * Check if a user is the last uploader
 771          *
 772          * @param User $user
 773          * @param string $img, image name
 774          * @return bool
 775          */
 776         public static function userCanReUpload( User $user, $img ) {
 777                 if( $user->isAllowed( 'reupload' ) )
 778                         return true; // non-conditional
 779                 if( !$user->isAllowed( 'reupload-own' ) )
 780                         return false;
 781                 if( is_string( $img ) )
 782                         $img = wfLocalFile( $img );
 783                 if ( !( $img instanceof LocalFile ) )
 784                         return false;
 785
 786                 return $user->getId() == $img->getUser( 'id' );
 787         }
 788
 789         public static function getExistsWarning( $file ) {
 790                 if( $file->exists() )
 791                         return array( 'exists', $file );
 792
 793                 if( $file->getTitle()->getArticleID() )
 794                         return array( 'page-exists', $file );
 795
 796                 if( strpos( $file->getName(), '.' ) == false ) {
 797                         $partname = $file->getName();
 798                         $rawExtension = '';
 799                 } else {
 800                         $n = strrpos( $file->getName(), '.' );
 801                         $rawExtension = substr( $file->getName(), $n + 1 );
 802                         $partname = substr( $file->getName(), 0, $n );
 803                 }
 804
 805                 if ( $rawExtension != $file->getExtension() ) {
 806                         // We're not using the normalized form of the extension.
 807                         // Normal form is lowercase, using most common of alternate
 808                         // extensions (eg 'jpg' rather than 'JPEG').
 809                         //
 810                         // Check for another file using the normalized form...
 811                         $nt_lc = Title::makeTitle( NS_FILE, $partname . '.' . $file->getExtension() );
 812                         $file_lc = wfLocalFile( $nt_lc );
 813
 814                         if( $file_lc->exists() )
 815                                 return array( 'exists-normalized', $file_lc );
 816                 }
 817
 818                 if ( self::isThumbName( $file->getName() ) ) {
 819                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
 820                         $nt_thb = Title::newFromText( substr( $partname , strpos( $partname , '-' ) +1 ) . '.' . $rawExtension );
 821                         $file_thb = wfLocalFile( $nt_thb );
 822                         if( $file_thb->exists() )
 823                                 return array( 'thumb', $file_thb );
 824                 }
 825
 826                 return false;
 827         }
 828
 829         public static function isThumbName( $filename ) {
 830                 $n = strrpos( $filename, '.' );
 831                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
 832                 return (
 833                                         substr( $partname , 3, 3 ) == 'px-' ||
 834                                         substr( $partname , 2, 3 ) == 'px-'
 835                                 ) &&
 836                                 ereg( "[0-9]{2}" , substr( $partname , 0, 2) );
 837         }
 838
 839         /**
 840          * Get a list of blacklisted filename prefixes from [[MediaWiki:filename-prefix-blacklist]]
 841          *
 842          * @return array list of prefixes
 843          */
 844         public static function getFilenamePrefixBlacklist() {
 845                 $blacklist = array();
 846                 $message = wfMsgForContent( 'filename-prefix-blacklist' );
 847                 if( $message && !( wfEmptyMsg( 'filename-prefix-blacklist', $message ) || $message == '-' ) ) {
 848                         $lines = explode( "\n", $message );
 849                         foreach( $lines as $line ) {
 850                                 // Remove comment lines
 851                                 $comment = substr( trim( $line ), 0, 1 );
 852                                 if ( $comment == '#' || $comment == '' ) {
 853                                         continue;
 854                                 }
 855                                 // Remove additional comments after a prefix
 856                                 $comment = strpos( $line, '#' );
 857                                 if ( $comment > 0 ) {
 858                                         $line = substr( $line, 0, $comment-1 );
 859                                 }
 860                                 $blacklist[] = trim( $line );
 861                         }
 862                 }
 863                 return $blacklist;
 864         }
 865
 866
 867 }