includes/UploadFromBase.php

   1 <?php
   2
   3 class UploadFromBase {
   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_LENGHT_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         static function isEnabled() {
  28                 global $wgEnableUploads;
  29                 return $wgEnableUploads;
  30         }
  31
  32         function __construct( $name ) {
  33                 $this->mDesiredDestName = $name;
  34         }
  35
  36
  37         function verifyUpload( &$resultDetails ) {
  38                 global $wgUser;
  39
  40                 /**
  41                  * If there was no filename or a zero size given, give up quick.
  42                  */
  43                 if( empty( $this->mFileSize ) ) {
  44                         return self::EMPTY_FILE;
  45                 }
  46
  47                 $nt = $this->getTitle();
  48                 if( is_null( $nt ) ) {
  49                         if( $this->mTitleError == self::ILLEGAL_FILENAME )
  50                                 $resultDetails = array( 'filtered' => $this->mFilteredName );
  51                         if ( $this->mTitleError == self::FILETYPE_BADTYPE )
  52                                 $resultDetails = array( 'finalExt' => $this->mFinalExtension );
  53                         return $this->mTitleError;
  54                 }
  55                 $this->mLocalFile = wfLocalFile( $nt );
  56                 $this->mDestName = $this->mLocalFile->getName();
  57
  58                 /**
  59                  * In some cases we may forbid overwriting of existing files.
  60                  */
  61                 $overwrite = $this->checkOverwrite( $this->mDestName );
  62                 if( $overwrite !== true ) {
  63                         $resultDetails = array( 'overwrite' => $overwrite );
  64                         return self::OVERWRITE_EXISTING_FILE;
  65                 }
  66
  67                 /**
  68                  * Look at the contents of the file; if we can recognize the
  69                  * type but it's corrupt or data of the wrong type, we should
  70                  * probably not accept it.
  71                  */
  72                 $veri = $this->verifyFile( $this->mTempPath );
  73
  74                 if( $veri !== true ) {
  75                         if( !is_array( $veri ) )
  76                                 $veri = array( $veri );
  77                         $resultDetails = array( 'veri' => $veri );
  78                         return self::VERIFICATION_ERROR;
  79                 }
  80
  81                 $error = '';
  82                 if( !wfRunHooks( 'UploadVerification',
  83                                 array( $this->mDestName, $this->mTempPath, &$error ) ) ) {
  84                         $resultDetails = array( 'error' => $error );
  85                         return self::UPLOAD_VERIFICATION_ERROR;
  86                 }
  87
  88                 return self::OK;
  89         }
  90
  91         /**
  92          * Verifies that it's ok to include the uploaded file
  93          *
  94          * @param string $tmpfile the full path of the temporary file to verify
  95          * @param string $extension The filename extension that the file is to be served with
  96          * @return mixed true of the file is verified, a WikiError object otherwise.
  97          */
  98         protected function verifyFile( $tmpfile ) {
  99                 $this->mFileProps = File::getPropsFromPath( $this->mTempPath,
 100                 $this->mFinalExtension );
 101                 $this->checkMacBinary();
 102
 103                 #magically determine mime type
 104                 $magic = MimeMagic::singleton();
 105                 $mime = $magic->guessMimeType( $tmpfile, false );
 106
 107                 #check mime type, if desired
 108                 global $wgVerifyMimeType;
 109                 if ( $wgVerifyMimeType ) {
 110
 111                   wfDebug ( "\n\nmime: <$mime> extension: <{$this->mFinalExtension}>\n\n");
 112                         #check mime type against file extension
 113                         if( !self::verifyExtension( $mime, $this->mFinalExtension ) ) {
 114                                 return 'uploadcorrupt';
 115                         }
 116
 117                         #check mime type blacklist
 118                         global $wgMimeTypeBlacklist;
 119                         if( isset($wgMimeTypeBlacklist) && !is_null($wgMimeTypeBlacklist)
 120                                 && $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 121                                 return array( 'filetype-badmime', $mime );
 122                         }
 123                 }
 124
 125                 #check for htmlish code and javascript
 126                 if( $this->detectScript ( $tmpfile, $mime, $this->mFinalExtension ) ) {
 127                         return 'uploadscripted';
 128                 }
 129
 130                 /**
 131                 * Scan the uploaded file for viruses
 132                 */
 133                 $virus = $this->detectVirus($tmpfile);
 134                 if ( $virus ) {
 135                         return array( 'uploadvirus', $virus );
 136                 }
 137
 138                 wfDebug( __METHOD__.": all clear; passing.\n" );
 139                 return true;
 140         }
 141
 142         function verifyPermissions( $user ) {
 143                 /**
 144                  * If the image is protected, non-sysop users won't be able
 145                  * to modify it by uploading a new revision.
 146                  */
 147                 $nt = $this->getTitle();
 148                 if( is_null( $nt ) )
 149                         return true;
 150                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 151                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 152                 $permErrorsCreate = ( $nt->exists() ? array() : $nt->getUserPermissionsErrors( 'create', $user ) );
 153                 if( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 154                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 155                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 156                         return $permErrors;
 157                 }
 158                 return true;
 159         }
 160
 161         function checkWarnings() {
 162                 $warning = array();
 163
 164                 $filename = $this->mLocalFile->getName();
 165                 $n = strrpos( $filename, '.' );
 166                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
 167
 168                 global $wgCapitalLinks;
 169                 if( $this->mDesiredDestName != $filename )
 170                         // Use mFilteredName so that we don't have to bother about spaces
 171                         $warning['badfilename'] = $filename;
 172
 173                 global $wgCheckFileExtensions, $wgFileExtensions;
 174                 if ( $wgCheckFileExtensions ) {
 175                         if ( !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) )
 176                                 $warning['filetype-unwanted-type'] = $this->mFinalExtension;
 177                 }
 178
 179                 global $wgUploadSizeWarning;
 180                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) )
 181                         $warning['large-file'] = $wgUploadSizeWarning;
 182
 183                 if ( $this->mFileSize == 0 )
 184                         $warning['emptyfile'] = true;
 185
 186                 $exists = self::getExistsWarning( $this->mLocalFile );
 187                 if( $exists !== false )
 188                         $warning['exists'] = $exists;
 189
 190
 191                 if( $exists !== false && $exists[0] != 'thumb'
 192                                 && self::isThumbName( $this->mLocalFile->getName() ) )
 193                         $warning['file-thumbnail-no'] = substr( $filename , 0,
 194                                 strpos( $nt->getText() , '-' ) +1 );
 195
 196                 $hash = File::sha1Base36( $this->mTempPath );
 197                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 198                 if( $dupes )
 199                         $warning['duplicate'] = $dupes;
 200
 201                 $filenamePrefixBlacklist = self::getFilenamePrefixBlacklist();
 202                 foreach( $filenamePrefixBlacklist as $prefix ) {
 203                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
 204                                 $warning['filename-bad-prefix'] = $prefix;
 205                                 break;
 206                         }
 207                 }
 208
 209                 # If the file existed before and was deleted, warn the user of this
 210                 # Don't bother doing so if the file exists now, however
 211                 if( $this->mLocalFile->wasDeleted() && !$file->exists() )
 212                         $warning['filewasdeleted'] = true;
 213
 214                 return $warning;
 215         }
 216
 217         function performUpload( $comment, $pageText, $watch, $user ) {
 218                 $status = $this->mLocalFile->upload( $this->mTempPath, $comment, $pageText,
 219                         File::DELETE_SOURCE, $this->mFileProps, false, $user );
 220
 221                 if( $status->isGood() && $watch ) {
 222                         $user->addWatch( $this->mLocalFile->getTitle() );
 223                 }
 224
 225                 if( $status->isGood() )
 226                         wfRunHooks( 'UploadComplete', array( &$this ) );
 227
 228                 return $status;
 229         }
 230
 231         /**
 232          * Returns a title or null
 233          */
 234         function getTitle() {
 235                 if ( $this->mTitle !== false )
 236                         return $this->mTitle;
 237
 238                 /**
 239                  * Chop off any directories in the given filename. Then
 240                  * filter out illegal characters, and try to make a legible name
 241                  * out of it. We'll strip some silently that Title would die on.
 242                  */
 243
 244                 $basename = $this->mDesiredDestName;
 245
 246                 $this->mFilteredName = wfStripIllegalFilenameChars( $basename );
 247
 248                 /**
 249                  * We'll want to blacklist against *any* 'extension', and use
 250                  * only the final one for the whitelist.
 251                  */
 252                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 253
 254                 if( count( $ext ) ) {
 255                         $this->mFinalExtension = $ext[count( $ext ) - 1];
 256                 } else {
 257                         $this->mFinalExtension = '';
 258                 }
 259
 260                 /* Don't allow users to override the blacklist (check file extension) */
 261                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 262                 global $wgFileExtensions, $wgFileBlacklist;
 263                 if ( $this->mFinalExtension == '' ) {
 264                         $this->mTitleError = self::FILETYPE_MISSING;
 265                         return $this->mTitle = null;
 266                 } elseif ( $this->checkFileExtensionList( $ext, $wgFileBlacklist ) ||
 267                                 ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 268                                         !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) ) {
 269                         $this->mTitleError = self::FILETYPE_BADTYPE;
 270                         return $this->mTitle = null;
 271                 }
 272
 273                 # If there was more than one "extension", reassemble the base
 274                 # filename to prevent bogus complaints about length
 275                 if( count( $ext ) > 1 ) {
 276                         for( $i = 0; $i < count( $ext ) - 1; $i++ )
 277                                 $partname .= '.' . $ext[$i];
 278                 }
 279
 280                 if( strlen( $partname ) < 1 ) {
 281                         $this->mTitleError =  self::MIN_LENGHT_PARTNAME;
 282                         return $this->mTitle = null;
 283                 }
 284
 285                 $nt = Title::makeTitleSafe( NS_IMAGE, $this->mFilteredName );
 286                 if( is_null( $nt ) ) {
 287                         $this->mTitleError = self::ILLEGAL_FILENAME;
 288                         return $this->mTitle = null;
 289                 }
 290                 return $this->mTitle = $nt;
 291         }
 292
 293         function getLocalFile() {
 294                 if( is_null( $this->mLocalFile ) ) {
 295                         $nt = $this->getTitle();
 296                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 297                 }
 298                 return $this->mLocalFile;
 299         }
 300
 301         /**
 302          * Stash a file in a temporary directory for later processing
 303          * after the user has confirmed it.
 304          *
 305          * If the user doesn't explicitly cancel or accept, these files
 306          * can accumulate in the temp directory.
 307          *
 308          * @param string $saveName - the destination filename
 309          * @param string $tempName - the source temporary file to save
 310          * @return string - full path the stashed file, or false on failure
 311          * @access private
 312          */
 313         function saveTempUploadedFile( $saveName, $tempName ) {
 314                 global $wgOut;
 315                 $repo = RepoGroup::singleton()->getLocalRepo();
 316                 $status = $repo->storeTemp( $saveName, $tempName );
 317                 if ( !$status->isGood() ) {
 318                         $this->showError( $status->getWikiText() );
 319                         return false;
 320                 } else {
 321                         return $status->value;
 322                 }
 323         }
 324
 325         /**
 326          * Stash a file in a temporary directory for later processing,
 327          * and save the necessary descriptive info into the session.
 328          * Returns a key value which will be passed through a form
 329          * to pick up the path info on a later invocation.
 330          *
 331          * @return int
 332          * @access private
 333          */
 334         function stashSession() {
 335                 $stash = $this->saveTempUploadedFile( $this->mDestName, $this->mTempPath );
 336
 337                 if( !$stash ) {
 338                         # Couldn't save the file.
 339                         return false;
 340                 }
 341
 342                 $key = mt_rand( 0, 0x7fffffff );
 343                 $_SESSION['wsUploadData'][$key] = array(
 344                         'mTempPath'       => $stash,
 345                         'mFileSize'       => $this->mFileSize,
 346                         'mSrcName'        => $this->mSrcName,
 347                         'mFileProps'      => $this->mFileProps,
 348                         'version'         => self::SESSION_VERSION,
 349                 );
 350                 return $key;
 351         }
 352
 353         /**
 354          * Remove a temporarily kept file stashed by saveTempUploadedFile().
 355          * @return success
 356          */
 357         function unsaveUploadedFile() {
 358                 $repo = RepoGroup::singleton()->getLocalRepo();
 359                 $success = $repo->freeTemp( $this->mTempPath );
 360                 return $success;
 361         }
 362
 363         /**
 364          * If we've modified the upload file we need to manually remove it
 365          * on exit to clean up.
 366          * @access private
 367          */
 368         function cleanupTempFile() {
 369                 if ( $this->mRemoveTempFile && file_exists( $this->mTempPath ) ) {
 370                         wfDebug( __METHOD__.": Removing temporary file {$this->mTempPath}\n" );
 371                         unlink( $this->mTempPath );
 372                 }
 373         }
 374
 375         function getTempPath() {
 376                 return $this->mTempPath;
 377         }
 378
 379
 380                 /**
 381          * Split a file into a base name and all dot-delimited 'extensions'
 382          * on the end. Some web server configurations will fall back to
 383          * earlier pseudo-'extensions' to determine type and execute
 384          * scripts, so the blacklist needs to check them all.
 385          *
 386          * @return array
 387          */
 388         function splitExtensions( $filename ) {
 389                 $bits = explode( '.', $filename );
 390                 $basename = array_shift( $bits );
 391                 return array( $basename, $bits );
 392         }
 393
 394         /**
 395          * Perform case-insensitive match against a list of file extensions.
 396          * Returns true if the extension is in the list.
 397          *
 398          * @param string $ext
 399          * @param array $list
 400          * @return bool
 401          */
 402         function checkFileExtension( $ext, $list ) {
 403                 return in_array( strtolower( $ext ), $list );
 404         }
 405
 406         /**
 407          * Perform case-insensitive match against a list of file extensions.
 408          * Returns true if any of the extensions are in the list.
 409          *
 410          * @param array $ext
 411          * @param array $list
 412          * @return bool
 413          */
 414         function checkFileExtensionList( $ext, $list ) {
 415                 foreach( $ext as $e ) {
 416                         if( in_array( strtolower( $e ), $list ) ) {
 417                                 return true;
 418                         }
 419                 }
 420                 return false;
 421         }
 422
 423
 424         /**
 425          * Checks if the mime type of the uploaded file matches the file extension.
 426          *
 427          * @param string $mime the mime type of the uploaded file
 428          * @param string $extension The filename extension that the file is to be served with
 429          * @return bool
 430          */
 431         public static function verifyExtension( $mime, $extension ) {
 432                 $magic = MimeMagic::singleton();
 433
 434                 if ( ! $mime || $mime == 'unknown' || $mime == 'unknown/unknown' )
 435                         if ( ! $magic->isRecognizableExtension( $extension ) ) {
 436                                 wfDebug( __METHOD__.": passing file with unknown detected mime type; " .
 437                                         "unrecognized extension '$extension', can't verify\n" );
 438                                 return true;
 439                         } else {
 440                                 wfDebug( __METHOD__.": rejecting file with unknown detected mime type; ".
 441                                         "recognized extension '$extension', so probably invalid file\n" );
 442                                 return false;
 443                         }
 444
 445                 $match= $magic->isMatchingExtension($extension,$mime);
 446
 447                 if ($match===NULL) {
 448                         wfDebug( __METHOD__.": no file extension known for mime type $mime, passing file\n" );
 449                         return true;
 450                 } elseif ($match===true) {
 451                         wfDebug( __METHOD__.": mime type $mime matches extension $extension, passing file\n" );
 452
 453                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 454                         return true;
 455
 456                 } else {
 457                         wfDebug( __METHOD__.": mime type $mime mismatches file extension $extension, rejecting file\n" );
 458                         return false;
 459                 }
 460         }
 461
 462         /**
 463          * Heuristic for detecting files that *could* contain JavaScript instructions or
 464          * things that may look like HTML to a browser and are thus
 465          * potentially harmful. The present implementation will produce false positives in some situations.
 466          *
 467          * @param string $file Pathname to the temporary upload file
 468          * @param string $mime The mime type of the file
 469          * @param string $extension The extension of the file
 470          * @return bool true if the file contains something looking like embedded scripts
 471          */
 472         function detectScript($file, $mime, $extension) {
 473                 global $wgAllowTitlesInSVG;
 474
 475                 #ugly hack: for text files, always look at the entire file.
 476                 #For binary field, just check the first K.
 477
 478                 if (strpos($mime,'text/')===0) $chunk = file_get_contents( $file );
 479                 else {
 480                         $fp = fopen( $file, 'rb' );
 481                         $chunk = fread( $fp, 1024 );
 482                         fclose( $fp );
 483                 }
 484
 485                 $chunk= strtolower( $chunk );
 486
 487                 if (!$chunk) return false;
 488
 489                 #decode from UTF-16 if needed (could be used for obfuscation).
 490                 if (substr($chunk,0,2)=="\xfe\xff") $enc= "UTF-16BE";
 491                 elseif (substr($chunk,0,2)=="\xff\xfe") $enc= "UTF-16LE";
 492                 else $enc= NULL;
 493
 494                 if ($enc) $chunk= iconv($enc,"ASCII//IGNORE",$chunk);
 495
 496                 $chunk= trim($chunk);
 497
 498                 #FIXME: convert from UTF-16 if necessarry!
 499
 500                 wfDebug("SpecialUpload::detectScript: checking for embedded scripts and HTML stuff\n");
 501
 502                 #check for HTML doctype
 503                 if (eregi("<!DOCTYPE *X?HTML",$chunk)) return true;
 504
 505                 /**
 506                 * Internet Explorer for Windows performs some really stupid file type
 507                 * autodetection which can cause it to interpret valid image files as HTML
 508                 * and potentially execute JavaScript, creating a cross-site scripting
 509                 * attack vectors.
 510                 *
 511                 * Apple's Safari browser also performs some unsafe file type autodetection
 512                 * which can cause legitimate files to be interpreted as HTML if the
 513                 * web server is not correctly configured to send the right content-type
 514                 * (or if you're really uploading plain text and octet streams!)
 515                 *
 516                 * Returns true if IE is likely to mistake the given file for HTML.
 517                 * Also returns true if Safari would mistake the given file for HTML
 518                 * when served with a generic content-type.
 519                 */
 520
 521                 $tags = array(
 522                         '<body',
 523                         '<head',
 524                         '<html',   #also in safari
 525                         '<img',
 526                         '<pre',
 527                         '<script', #also in safari
 528                         '<table'
 529                         );
 530                 if( ! $wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
 531                         $tags[] = '<title';
 532                 }
 533
 534                 foreach( $tags as $tag ) {
 535                         if( false !== strpos( $chunk, $tag ) ) {
 536                                 return true;
 537                         }
 538                 }
 539
 540                 /*
 541                 * look for javascript
 542                 */
 543
 544                 #resolve entity-refs to look at attributes. may be harsh on big files... cache result?
 545                 $chunk = Sanitizer::decodeCharReferences( $chunk );
 546
 547                 #look for script-types
 548                 if (preg_match('!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim',$chunk)) return true;
 549
 550                 #look for html-style script-urls
 551                 if (preg_match('!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim',$chunk)) return true;
 552
 553                 #look for css-style script-urls
 554                 if (preg_match('!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim',$chunk)) return true;
 555
 556                 wfDebug("SpecialUpload::detectScript: no scripts found\n");
 557                 return false;
 558         }
 559
 560         /**
 561          * Generic wrapper function for a virus scanner program.
 562          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
 563          * $wgAntivirusRequired may be used to deny upload if the scan fails.
 564          *
 565          * @param string $file Pathname to the temporary upload file
 566          * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
 567          *         or a string containing feedback from the virus scanner if a virus was found.
 568          *         If textual feedback is missing but a virus was found, this function returns true.
 569          */
 570         function detectVirus($file) {
 571                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
 572
 573                 if ( !$wgAntivirus ) {
 574                         wfDebug( __METHOD__.": virus scanner disabled\n");
 575                         return NULL;
 576                 }
 577
 578                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
 579                         wfDebug( __METHOD__.": unknown virus scanner: $wgAntivirus\n" );
 580                         $wgOut->wrapWikiMsg( '<div class="error">$1</div>', array( 'virus-badscanner', $wgAntivirus ) );
 581                         return wfMsg('virus-unknownscanner') . " $wgAntivirus";
 582                 }
 583
 584                 # look up scanner configuration
 585                 $command = $wgAntivirusSetup[$wgAntivirus]["command"];
 586                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]["codemap"];
 587                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]["messagepattern"] ) ?
 588                         $wgAntivirusSetup[$wgAntivirus]["messagepattern"] : null;
 589
 590                 if ( strpos( $command,"%f" ) === false ) {
 591                         # simple pattern: append file to scan
 592                         $command .= " " . wfEscapeShellArg( $file );
 593                 } else {
 594                         # complex pattern: replace "%f" with file to scan
 595                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
 596                 }
 597
 598                 wfDebug( __METHOD__.": running virus scan: $command \n" );
 599
 600                 # execute virus scanner
 601                 $exitCode = false;
 602
 603                 #NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
 604                 #      that does not seem to be worth the pain.
 605                 #      Ask me (Duesentrieb) about it if it's ever needed.
 606                 $output = array();
 607                 if ( wfIsWindows() ) {
 608                         exec( "$command", $output, $exitCode );
 609                 } else {
 610                         exec( "$command 2>&1", $output, $exitCode );
 611                 }
 612
 613                 # map exit code to AV_xxx constants.
 614                 $mappedCode = $exitCode;
 615                 if ( $exitCodeMap ) {
 616                         if ( isset( $exitCodeMap[$exitCode] ) ) {
 617                                 $mappedCode = $exitCodeMap[$exitCode];
 618                         } elseif ( isset( $exitCodeMap["*"] ) ) {
 619                                 $mappedCode = $exitCodeMap["*"];
 620                         }
 621                 }
 622
 623                 if ( $mappedCode === AV_SCAN_FAILED ) {
 624                         # scan failed (code was mapped to false by $exitCodeMap)
 625                         wfDebug( __METHOD__.": failed to scan $file (code $exitCode).\n" );
 626
 627                         if ( $wgAntivirusRequired ) {
 628                                 return wfMsg('virus-scanfailed', array( $exitCode ) );
 629                         } else {
 630                                 return NULL;
 631                         }
 632                 } else if ( $mappedCode === AV_SCAN_ABORTED ) {
 633                         # scan failed because filetype is unknown (probably imune)
 634                         wfDebug( __METHOD__.": unsupported file type $file (code $exitCode).\n" );
 635                         return NULL;
 636                 } else if ( $mappedCode === AV_NO_VIRUS ) {
 637                         # no virus found
 638                         wfDebug( __METHOD__.": file passed virus scan.\n" );
 639                         return false;
 640                 } else {
 641                         $output = join( "\n", $output );
 642                         $output = trim( $output );
 643
 644                         if ( !$output ) {
 645                                 $output = true; #if there's no output, return true
 646                         } elseif ( $msgPattern ) {
 647                                 $groups = array();
 648                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
 649                                         if ( $groups[1] ) {
 650                                                 $output = $groups[1];
 651                                         }
 652                                 }
 653                         }
 654
 655                         wfDebug( __METHOD__.": FOUND VIRUS! scanner feedback: $output" );
 656                         return $output;
 657                 }
 658         }
 659
 660         /**
 661          * Check if the temporary file is MacBinary-encoded, as some uploads
 662          * from Internet Explorer on Mac OS Classic and Mac OS X will be.
 663          * If so, the data fork will be extracted to a second temporary file,
 664          * which will then be checked for validity and either kept or discarded.
 665          *
 666          * @access private
 667          */
 668         function checkMacBinary() {
 669                 $macbin = new MacBinary( $this->mTempPath );
 670                 if( $macbin->isValid() ) {
 671                         $dataFile = tempnam( wfTempDir(), "WikiMacBinary" );
 672                         $dataHandle = fopen( $dataFile, 'wb' );
 673
 674                         wfDebug( "SpecialUpload::checkMacBinary: Extracting MacBinary data fork to $dataFile\n" );
 675                         $macbin->extractData( $dataHandle );
 676
 677                         $this->mTempPath = $dataFile;
 678                         $this->mFileSize = $macbin->dataForkLength();
 679
 680                         // We'll have to manually remove the new file if it's not kept.
 681                         $this->mRemoveTempFile = true;
 682                 }
 683                 $macbin->close();
 684         }
 685
 686         /**
 687          * Check if there's an overwrite conflict and, if so, if restrictions
 688          * forbid this user from performing the upload.
 689          *
 690          * @return mixed true on success, WikiError on failure
 691          * @access private
 692          */
 693         function checkOverwrite() {
 694                 global $wgUser;
 695                 // First check whether the local file can be overwritten
 696                 if( $this->mLocalFile->exists() )
 697                         if( !self::userCanReUpload( $wgUser, $this->mLocalFile ) )
 698                                 return 'fileexists-forbidden';
 699
 700                 // Check shared conflicts
 701                 $file = wfFindFile( $this->mLocalFile->getName() );
 702                 if ( $file && ( !$wgUser->isAllowed( 'reupload' ) ||
 703                                 !$wgUser->isAllowed( 'reupload-shared' ) ) )
 704                         return 'fileexists-shared-forbidden';
 705
 706                 return true;
 707
 708         }
 709
 710         /**
 711          * Check if a user is the last uploader
 712          *
 713          * @param User $user
 714          * @param string $img, image name
 715          * @return bool
 716          */
 717         public static function userCanReUpload( User $user, $img ) {
 718                 if( $user->isAllowed( 'reupload' ) )
 719                         return true; // non-conditional
 720                 if( !$user->isAllowed( 'reupload-own' ) )
 721                         return false;
 722                 if( is_string( $img ) )
 723                         $img = wfLocalFile( $img );
 724                 if ( !( $img instanceof LocalFile ) )
 725                         return false;
 726
 727                 return $user->getId() == $img->getUser( 'id' );
 728         }
 729
 730         public static function getExistsWarning( $file ) {
 731                 if( $file->exists() )
 732                         return array( 'exists', $file );
 733
 734                 if( $file->getTitle()->getArticleID() )
 735                         return array( 'page-exists', false );
 736
 737                 if( strpos( $file->getName(), '.' ) == false ) {
 738                         $partname = $file->getName();
 739                         $rawExtension = '';
 740                 } else {
 741                         $n = strrpos( $file->getName(), '.' );
 742                         $rawExtension = substr( $file->getName(), $n + 1 );
 743                         $partname = substr( $file->getName(), 0, $n );
 744                 }
 745
 746                 if ( $rawExtension != $file->getExtension() ) {
 747                         // We're not using the normalized form of the extension.
 748                         // Normal form is lowercase, using most common of alternate
 749                         // extensions (eg 'jpg' rather than 'JPEG').
 750                         //
 751                         // Check for another file using the normalized form...
 752                         $nt_lc = Title::makeTitle( NS_IMAGE, $partname . '.' . $file->getExtension() );
 753                         $file_lc = wfLocalFile( $nt_lc );
 754
 755                         if( $file_lc->exists() )
 756                                 return array( 'exists-normalized', $file_lc );
 757                 }
 758
 759                 if ( self::isThumbName( $file->getName() ) ) {
 760                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
 761                         $nt_thb = Title::newFromText( substr( $partname , strpos( $partname , '-' ) +1 ) . '.' . $rawExtension );
 762                         $file_thb = wfLocalFile( $nt_thb );
 763                         if( $file_thb->exists() )
 764                                 return array( 'thumb', $file_thb );
 765                 }
 766
 767                 return false;
 768         }
 769
 770         public static function isThumbName( $filename ) {
 771                 $n = strrpos( $filename, '.' );
 772                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
 773                 return (
 774                                         substr( $partname , 3, 3 ) == 'px-' ||
 775                                         substr( $partname , 2, 3 ) == 'px-'
 776                                 ) &&
 777                                 ereg( "[0-9]{2}" , substr( $partname , 0, 2) );
 778         }
 779
 780         /**
 781          * Get a list of blacklisted filename prefixes from [[MediaWiki:filename-prefix-blacklist]]
 782          *
 783          * @return array list of prefixes
 784          */
 785         public static function getFilenamePrefixBlacklist() {
 786                 $blacklist = array();
 787                 $message = wfMsgForContent( 'filename-prefix-blacklist' );
 788                 if( $message && !( wfEmptyMsg( 'filename-prefix-blacklist', $message ) || $message == '-' ) ) {
 789                         $lines = explode( "\n", $message );
 790                         foreach( $lines as $line ) {
 791                                 // Remove comment lines
 792                                 $comment = substr( trim( $line ), 0, 1 );
 793                                 if ( $comment == '#' || $comment == '' ) {
 794                                         continue;
 795                                 }
 796                                 // Remove additional comments after a prefix
 797                                 $comment = strpos( $line, '#' );
 798                                 if ( $comment > 0 ) {
 799                                         $line = substr( $line, 0, $comment-1 );
 800                                 }
 801                                 $blacklist[] = trim( $line );
 802                         }
 803                 }
 804                 return $blacklist;
 805         }
 806
 807
 808 }