includes/SpecialUpload.php

   1 <?php
   2 /**
   3  *
   4  * @package MediaWiki
   5  * @subpackage SpecialPage
   6  */
   7
   8 /**
   9  *
  10  */
  11 require_once 'Image.php';
  12 /**
  13  * Entry point
  14  */
  15 function wfSpecialUpload() {
  16         global $wgRequest;
  17         $form = new UploadForm( $wgRequest );
  18         $form->execute();
  19 }
  20
  21 /**
  22  *
  23  * @package MediaWiki
  24  * @subpackage SpecialPage
  25  */
  26 class UploadForm {
  27         /**#@+
  28          * @access private
  29          */
  30         var $mUploadFile, $mUploadDescription, $mLicense ,$mIgnoreWarning, $mUploadError;
  31         var $mUploadSaveName, $mUploadTempName, $mUploadSize, $mUploadOldVersion;
  32         var $mUploadCopyStatus, $mUploadSource, $mReUpload, $mAction, $mUpload;
  33         var $mOname, $mSessionKey, $mStashed, $mDestFile, $mRemoveTempFile, $mSourceType;
  34         /**#@-*/
  35
  36         /**
  37          * Constructor : initialise object
  38          * Get data POSTed through the form and assign them to the object
  39          * @param $request Data posted.
  40          */
  41         function UploadForm( &$request ) {
  42                 global $wgAllowCopyUploads;
  43                 $this->mDestFile          = $request->getText( 'wpDestFile' );
  44
  45                 if( !$request->wasPosted() ) {
  46                         # GET requests just give the main form; no data except wpDestfile.
  47                         return;
  48                 }
  49
  50                 $this->mIgnoreWarning     = $request->getCheck( 'wpIgnoreWarning' );
  51                 $this->mReUpload          = $request->getCheck( 'wpReUpload' );
  52                 $this->mUpload            = $request->getCheck( 'wpUpload' );
  53
  54                 $this->mUploadDescription = $request->getText( 'wpUploadDescription' );
  55                 $this->mLicense           = $request->getText( 'wpLicense' );
  56                 $this->mUploadCopyStatus  = $request->getText( 'wpUploadCopyStatus' );
  57                 $this->mUploadSource      = $request->getText( 'wpUploadSource' );
  58                 $this->mWatchthis         = $request->getBool( 'wpWatchthis' );
  59                 $this->mSourceType         = $request->getBool( 'wpSourceType' );
  60                 wfDebug( "UploadForm: watchthis is: '$this->mWatchthis'\n" );
  61
  62                 $this->mAction            = $request->getVal( 'action' );
  63
  64                 $this->mSessionKey        = $request->getInt( 'wpSessionKey' );
  65                 if( !empty( $this->mSessionKey ) &&
  66                         isset( $_SESSION['wsUploadData'][$this->mSessionKey] ) ) {
  67                         /**
  68                          * Confirming a temporarily stashed upload.
  69                          * We don't want path names to be forged, so we keep
  70                          * them in the session on the server and just give
  71                          * an opaque key to the user agent.
  72                          */
  73                         $data = $_SESSION['wsUploadData'][$this->mSessionKey];
  74                         $this->mUploadTempName   = $data['mUploadTempName'];
  75                         $this->mUploadSize       = $data['mUploadSize'];
  76                         $this->mOname            = $data['mOname'];
  77                         $this->mUploadError      = 0/*UPLOAD_ERR_OK*/;
  78                         $this->mStashed          = true;
  79                         $this->mRemoveTempFile   = false;
  80                 } else {
  81                         /**
  82                          *Check for a newly uploaded file.
  83                          */
  84                         if( $wgAllowCopyUploads && $this->mSourceType == 'web' ) {
  85                                 $this->initializeFromUrl( $request );
  86                         } else {
  87                                 $this->initializeFromUpload( $request );
  88                         }
  89                 }
  90         }
  91
  92         /**
  93          * Initialize the uploaded file from PHP data
  94          * @access private
  95          */
  96         function initializeFromUpload( $request ) {
  97                 $this->mUploadTempName = $request->getFileTempName( 'wpUploadFile' );
  98                 $this->mUploadSize     = $request->getFileSize( 'wpUploadFile' );
  99                 $this->mOname          = $request->getFileName( 'wpUploadFile' );
 100                 $this->mUploadError    = $request->getUploadError( 'wpUploadFile' );
 101                 $this->mSessionKey     = false;
 102                 $this->mStashed        = false;
 103                 $this->mRemoveTempFile = false; // PHP will handle this
 104         }
 105
 106         /**
 107          * Copy a web file to a temporary file
 108          * @access private
 109          */
 110         function initializeFromUrl( $request ) {
 111                 global $wgTmpDirectory, $wgMaxUploadSize;
 112                 $url = $request->getText( 'wpUploadFile' );
 113                 $local_file = tempnam( $wgTmpDirectory, 'WEBUPLOAD' );
 114
 115                 $this->mUploadTempName = $local_file;
 116                 $this->mUploadError    = $this->curlCopy( $url, $local_file );
 117                 $this->mUploadSize     = $this->mUploadTempFileSize;
 118                 $this->mOname          = array_pop( explode( '/', $url ) );
 119                 $this->mSessionKey     = false;
 120                 $this->mStashed        = false;
 121
 122                 // PHP won't auto-cleanup the file
 123                 $this->mRemoveTempFile = file_exists( $local_file );
 124         }
 125
 126         /**
 127          * Safe copy from URL
 128          * Returns true if there was an error, false otherwise
 129          */
 130         private function curlCopy( $url, $dest ) {
 131                 global $wgMaxUploadSize, $wgUser;
 132
 133                 if( !$wgUser->isAllowed( 'upload_by_url' ) ) {
 134                         $wgOut->permissionRequired( 'upload_by_url' );
 135                         return true;
 136                 }
 137
 138                 # Maybe remove some pasting blanks :-)
 139                 $url = strtolower( trim( $url ) );
 140                 if( substr( $u, 0, 7 ) != 'http://' && substr( $u, 0, 6 ) != 'ftp://' ) {
 141                         # Only HTTP or FTP URLs
 142                         return true;
 143                 }
 144
 145                 # Open temporary file
 146                 $this->mUploadTempFileSize = 0;
 147                 $this->mUploadTempFile = @fopen( $this->mUploadTempName, "wb" );
 148                 if( $this->mUploadTempFile === false ) {
 149                         # Could not open temporary file to write in
 150                         return true;
 151                 }
 152
 153                 $ch = curl_init();
 154                 curl_setopt( $ch, CURLOPT_HTTP_VERSION, 1.0); # Probably not needed, but apparently can work around some bug
 155                 curl_setopt( $ch, CURLOPT_TIMEOUT, 10); # 10 seconds timeout
 156                 curl_setopt( $ch, CURLOPT_LOW_SPEED_LIMIT, 512); # 0.5KB per second minimum transfer speed
 157                 curl_setopt( $ch, CURLOPT_URL, $url);
 158                 curl_setopt( $ch, CURLOPT_WRITEFUNCTION, array( $this, 'uploadCurlCallback' ) );
 159                 curl_exec( $ch );
 160                 $error = curl_errno( $ch ) ? true : false;
 161 #               if ( $error ) print curl_error ( $ch ) ; # Debugging output
 162                 curl_close( $ch );
 163
 164                 fclose( $this->mUploadTempFile );
 165                 unset( $this->mUploadTempFile );
 166                 if( $error ) {
 167                         unlink( $dest );
 168                 }
 169
 170                 return $error;
 171         }
 172
 173         /**
 174          * Callback function for CURL-based web transfer
 175          * Write data to file unless we've passed the length limit;
 176          * if so, abort immediately.
 177          * @access private
 178          */
 179         function uploadCurlCallback( $ch, $data ) {
 180                 global $wgMaxUploadSize;
 181                 $length = strlen( $data );
 182                 $this->mUploadTempFileSize += $length;
 183                 if( $this->mUploadTempFileSize > $wgMaxUploadSize ) {
 184                         return 0;
 185                 }
 186                 fwrite( $this->mUploadTempFile, $data );
 187                 return $length;
 188         }
 189
 190         /**
 191          * Start doing stuff
 192          * @access public
 193          */
 194         function execute() {
 195                 global $wgUser, $wgOut;
 196                 global $wgEnableUploads, $wgUploadDirectory;
 197
 198                 # Check uploading enabled
 199                 if( !$wgEnableUploads ) {
 200                         $wgOut->showErrorPage( 'uploaddisabled', 'uploaddisabledtext' );
 201                         return;
 202                 }
 203
 204                 # Check permissions
 205                 if( !$wgUser->isAllowed( 'upload' ) ) {
 206                         if( !$wgUser->isLoggedIn() ) {
 207                                 $wgOut->showErrorPage( 'uploadnologin', 'uploadnologintext' );
 208                         } else {
 209                                 $wgOut->permissionRequired( 'upload' );
 210                         }
 211                         return;
 212                 }
 213
 214                 # Check blocks
 215                 if( $wgUser->isBlocked() ) {
 216                         $wgOut->blockedPage();
 217                         return;
 218                 }
 219
 220                 if( wfReadOnly() ) {
 221                         $wgOut->readOnlyPage();
 222                         return;
 223                 }
 224
 225                 /** Check if the image directory is writeable, this is a common mistake */
 226                 if( !is_writeable( $wgUploadDirectory ) ) {
 227                         $wgOut->addWikiText( wfMsg( 'upload_directory_read_only', $wgUploadDirectory ) );
 228                         return;
 229                 }
 230
 231                 if( $this->mReUpload ) {
 232                         if( !$this->unsaveUploadedFile() ) {
 233                                 return;
 234                         }
 235                         $this->mainUploadForm();
 236                 } else if( 'submit' == $this->mAction || $this->mUpload ) {
 237                         $this->processUpload();
 238                 } else {
 239                         $this->mainUploadForm();
 240                 }
 241
 242                 $this->cleanupTempFile();
 243         }
 244
 245         /* -------------------------------------------------------------- */
 246
 247         /**
 248          * Really do the upload
 249          * Checks are made in SpecialUpload::execute()
 250          * @access private
 251          */
 252         function processUpload() {
 253                 global $wgUser, $wgOut;
 254
 255                 /* Check for PHP error if any, requires php 4.2 or newer */
 256                 if( $this->mUploadError == 1/*UPLOAD_ERR_INI_SIZE*/ ) {
 257                         $this->mainUploadForm( wfMsgHtml( 'largefileserver' ) );
 258                         return;
 259                 }
 260
 261                 /**
 262                  * If there was no filename or a zero size given, give up quick.
 263                  */
 264                 if( trim( $this->mOname ) == '' || empty( $this->mUploadSize ) ) {
 265                         $this->mainUploadForm( wfMsgHtml( 'emptyfile' ) );
 266                         return;
 267                 }
 268
 269                 # Chop off any directories in the given filename
 270                 if( $this->mDestFile ) {
 271                         $basename = wfBaseName( $this->mDestFile );
 272                 } else {
 273                         $basename = wfBaseName( $this->mOname );
 274                 }
 275
 276                 /**
 277                  * We'll want to blacklist against *any* 'extension', and use
 278                  * only the final one for the whitelist.
 279                  */
 280                 list( $partname, $ext ) = $this->splitExtensions( $basename );
 281
 282                 if( count( $ext ) ) {
 283                         $finalExt = $ext[count( $ext ) - 1];
 284                 } else {
 285                         $finalExt = '';
 286                 }
 287                 $fullExt = implode( '.', $ext );
 288
 289                 # If there was more than one "extension", reassemble the base
 290                 # filename to prevent bogus complaints about length
 291                 if( count( $ext ) > 1 ) {
 292                         for( $i = 0; $i < count( $ext ) - 1; $i++ )
 293                                 $partname .= '.' . $ext[$i];
 294                 }
 295
 296                 if( strlen( $partname ) < 3 ) {
 297                         $this->mainUploadForm( wfMsgHtml( 'minlength' ) );
 298                         return;
 299                 }
 300
 301                 /**
 302                  * Filter out illegal characters, and try to make a legible name
 303                  * out of it. We'll strip some silently that Title would die on.
 304                  */
 305                 $filtered = preg_replace ( "/[^".Title::legalChars()."]|:/", '-', $basename );
 306                 $nt = Title::newFromText( $filtered );
 307                 if( is_null( $nt ) ) {
 308                         $this->uploadError( wfMsgWikiHtml( 'illegalfilename', htmlspecialchars( $filtered ) ) );
 309                         return;
 310                 }
 311                 $nt =& Title::makeTitle( NS_IMAGE, $nt->getDBkey() );
 312                 $this->mUploadSaveName = $nt->getDBkey();
 313
 314                 /**
 315                  * If the image is protected, non-sysop users won't be able
 316                  * to modify it by uploading a new revision.
 317                  */
 318                 if( !$nt->userCanEdit() ) {
 319                         return $this->uploadError( wfMsgWikiHtml( 'protectedpage' ) );
 320                 }
 321
 322                 /**
 323                  * In some cases we may forbid overwriting of existing files.
 324                  */
 325                 $overwrite = $this->checkOverwrite( $this->mUploadSaveName );
 326                 if( WikiError::isError( $overwrite ) ) {
 327                         return $this->uploadError( $overwrite->toString() );
 328                 }
 329
 330                 /* Don't allow users to override the blacklist (check file extension) */
 331                 global $wgStrictFileExtensions;
 332                 global $wgFileExtensions, $wgFileBlacklist;
 333                 if( $this->checkFileExtensionList( $ext, $wgFileBlacklist ) ||
 334                         ($wgStrictFileExtensions &&
 335                                 !$this->checkFileExtension( $finalExt, $wgFileExtensions ) ) ) {
 336                         return $this->uploadError( wfMsgHtml( 'badfiletype', htmlspecialchars( $fullExt ) ) );
 337                 }
 338
 339                 /**
 340                  * Look at the contents of the file; if we can recognize the
 341                  * type but it's corrupt or data of the wrong type, we should
 342                  * probably not accept it.
 343                  */
 344                 if( !$this->mStashed ) {
 345                         $this->checkMacBinary();
 346                         $veri = $this->verify( $this->mUploadTempName, $finalExt );
 347
 348                         if( $veri !== true ) { //it's a wiki error...
 349                                 return $this->uploadError( $veri->toString() );
 350                         }
 351                 }
 352
 353                 /**
 354                  * Provide an opportunity for extensions to add futher checks
 355                  */
 356                 $error = '';
 357                 if( !wfRunHooks( 'UploadVerification',
 358                                 array( $this->mUploadSaveName, $this->mUploadTempName, &$error ) ) ) {
 359                         return $this->uploadError( $error );
 360                 }
 361
 362                 /**
 363                  * Check for non-fatal conditions
 364                  */
 365                 if ( ! $this->mIgnoreWarning ) {
 366                         $warning = '';
 367
 368                         global $wgCapitalLinks;
 369                         if( $wgCapitalLinks ) {
 370                                 $filtered = ucfirst( $filtered );
 371                         }
 372                         if( $this->mUploadSaveName != $filtered ) {
 373                                 $warning .=  '<li>'.wfMsgHtml( 'badfilename', htmlspecialchars( $this->mUploadSaveName ) ).'</li>';
 374                         }
 375
 376                         global $wgCheckFileExtensions;
 377                         if ( $wgCheckFileExtensions ) {
 378                                 if ( ! $this->checkFileExtension( $finalExt, $wgFileExtensions ) ) {
 379                                         $warning .= '<li>'.wfMsgHtml( 'badfiletype', htmlspecialchars( $fullExt ) ).'</li>';
 380                                 }
 381                         }
 382
 383                         global $wgUploadSizeWarning;
 384                         if ( $wgUploadSizeWarning && ( $this->mUploadSize > $wgUploadSizeWarning ) ) {
 385                                 # TODO: Format $wgUploadSizeWarning to something that looks better than the raw byte
 386                                 # value, perhaps add GB,MB and KB suffixes?
 387                                 $warning .= '<li>'.wfMsgHtml( 'largefile', $wgUploadSizeWarning, $this->mUploadSize ).'</li>';
 388                         }
 389                         if ( $this->mUploadSize == 0 ) {
 390                                 $warning .= '<li>'.wfMsgHtml( 'emptyfile' ).'</li>';
 391                         }
 392
 393                         if( $nt->getArticleID() ) {
 394                                 global $wgUser;
 395                                 $sk = $wgUser->getSkin();
 396                                 $dlink = $sk->makeKnownLinkObj( $nt );
 397                                 $warning .= '<li>'.wfMsgHtml( 'fileexists', $dlink ).'</li>';
 398                         } else {
 399                                 # If the file existed before and was deleted, warn the user of this
 400                                 # Don't bother doing so if the image exists now, however
 401                                 $image = new Image( $nt );
 402                                 if( $image->wasDeleted() ) {
 403                                         $skin = $wgUser->getSkin();
 404                                         $ltitle = Title::makeTitle( NS_SPECIAL, 'Log' );
 405                                         $llink = $skin->makeKnownLinkObj( $ltitle, wfMsgHtml( 'deletionlog' ), 'type=delete&page=' . $nt->getPrefixedUrl() );
 406                                         $warning .= wfOpenElement( 'li' ) . wfMsgWikiHtml( 'filewasdeleted', $llink ) . wfCloseElement( 'li' );
 407                                 }
 408                         }
 409
 410                         if( $warning != '' ) {
 411                                 /**
 412                                  * Stash the file in a temporary location; the user can choose
 413                                  * to let it through and we'll complete the upload then.
 414                                  */
 415                                 return $this->uploadWarning( $warning );
 416                         }
 417                 }
 418
 419                 /**
 420                  * Try actually saving the thing...
 421                  * It will show an error form on failure.
 422                  */
 423                 $hasBeenMunged = !empty( $this->mSessionKey ) || $this->mRemoveTempFile;
 424                 if( $this->saveUploadedFile( $this->mUploadSaveName,
 425                                              $this->mUploadTempName,
 426                                              $hasBeenMunged ) ) {
 427                         /**
 428                          * Update the upload log and create the description page
 429                          * if it's a new file.
 430                          */
 431                         $img = Image::newFromName( $this->mUploadSaveName );
 432                         $success = $img->recordUpload( $this->mUploadOldVersion,
 433                                                         $this->mUploadDescription,
 434                                                         $this->mLicense,
 435                                                         $this->mUploadCopyStatus,
 436                                                         $this->mUploadSource,
 437                                                         $this->mWatchthis );
 438
 439                         if ( $success ) {
 440                                 $this->showSuccess();
 441                                 wfRunHooks( 'UploadComplete', array( &$img ) );
 442                         } else {
 443                                 // Image::recordUpload() fails if the image went missing, which is
 444                                 // unlikely, hence the lack of a specialised message
 445                                 $wgOut->showFileNotFoundError( $this->mUploadSaveName );
 446                         }
 447                 }
 448         }
 449
 450         /**
 451          * Move the uploaded file from its temporary location to the final
 452          * destination. If a previous version of the file exists, move
 453          * it into the archive subdirectory.
 454          *
 455          * @todo If the later save fails, we may have disappeared the original file.
 456          *
 457          * @param string $saveName
 458          * @param string $tempName full path to the temporary file
 459          * @param bool $useRename if true, doesn't check that the source file
 460          *                        is a PHP-managed upload temporary
 461          */
 462         function saveUploadedFile( $saveName, $tempName, $useRename = false ) {
 463                 global $wgOut, $wgAllowCopyUploads;
 464
 465                 if ( !$useRename AND $wgAllowCopyUploads AND $this->mSourceType == 'web' ) $useRename = true;
 466
 467                 $fname= "SpecialUpload::saveUploadedFile";
 468
 469                 $dest = wfImageDir( $saveName );
 470                 $archive = wfImageArchiveDir( $saveName );
 471                 if ( !is_dir( $dest ) ) wfMkdirParents( $dest );
 472                 if ( !is_dir( $archive ) ) wfMkdirParents( $archive );
 473
 474                 $this->mSavedFile = "{$dest}/{$saveName}";
 475
 476                 if( is_file( $this->mSavedFile ) ) {
 477                         $this->mUploadOldVersion = gmdate( 'YmdHis' ) . "!{$saveName}";
 478                         wfSuppressWarnings();
 479                         $success = rename( $this->mSavedFile, "${archive}/{$this->mUploadOldVersion}" );
 480                         wfRestoreWarnings();
 481
 482                         if( ! $success ) {
 483                                 $wgOut->showFileRenameError( $this->mSavedFile,
 484                                   "${archive}/{$this->mUploadOldVersion}" );
 485                                 return false;
 486                         }
 487                         else wfDebug("$fname: moved file ".$this->mSavedFile." to ${archive}/{$this->mUploadOldVersion}\n");
 488                 }
 489                 else {
 490                         $this->mUploadOldVersion = '';
 491                 }
 492
 493                 wfSuppressWarnings();
 494                 $success = $useRename
 495                         ? rename( $tempName, $this->mSavedFile )
 496                         : move_uploaded_file( $tempName, $this->mSavedFile );
 497                 wfRestoreWarnings();
 498
 499                 if( ! $success ) {
 500                         $wgOut->showFileCopyError( $tempName, $this->mSavedFile );
 501                         return false;
 502                 } else {
 503                         wfDebug("$fname: wrote tempfile $tempName to ".$this->mSavedFile."\n");
 504                 }
 505
 506                 chmod( $this->mSavedFile, 0644 );
 507                 return true;
 508         }
 509
 510         /**
 511          * Stash a file in a temporary directory for later processing
 512          * after the user has confirmed it.
 513          *
 514          * If the user doesn't explicitly cancel or accept, these files
 515          * can accumulate in the temp directory.
 516          *
 517          * @param string $saveName - the destination filename
 518          * @param string $tempName - the source temporary file to save
 519          * @return string - full path the stashed file, or false on failure
 520          * @access private
 521          */
 522         function saveTempUploadedFile( $saveName, $tempName ) {
 523                 global $wgOut;
 524                 $archive = wfImageArchiveDir( $saveName, 'temp' );
 525                 if ( !is_dir ( $archive ) ) wfMkdirParents( $archive );
 526                 $stash = $archive . '/' . gmdate( "YmdHis" ) . '!' . $saveName;
 527
 528                 $success = $this->mRemoveTempFile
 529                         ? rename( $tempName, $stash )
 530                         : move_uploaded_file( $tempName, $stash );
 531                 if ( !$success ) {
 532                         $wgOut->showFileCopyError( $tempName, $stash );
 533                         return false;
 534                 }
 535
 536                 return $stash;
 537         }
 538
 539         /**
 540          * Stash a file in a temporary directory for later processing,
 541          * and save the necessary descriptive info into the session.
 542          * Returns a key value which will be passed through a form
 543          * to pick up the path info on a later invocation.
 544          *
 545          * @return int
 546          * @access private
 547          */
 548         function stashSession() {
 549                 $stash = $this->saveTempUploadedFile(
 550                         $this->mUploadSaveName, $this->mUploadTempName );
 551
 552                 if( !$stash ) {
 553                         # Couldn't save the file.
 554                         return false;
 555                 }
 556
 557                 $key = mt_rand( 0, 0x7fffffff );
 558                 $_SESSION['wsUploadData'][$key] = array(
 559                         'mUploadTempName' => $stash,
 560                         'mUploadSize'     => $this->mUploadSize,
 561                         'mOname'          => $this->mOname );
 562                 return $key;
 563         }
 564
 565         /**
 566          * Remove a temporarily kept file stashed by saveTempUploadedFile().
 567          * @access private
 568          * @return success
 569          */
 570         function unsaveUploadedFile() {
 571                 global $wgOut;
 572                 wfSuppressWarnings();
 573                 $success = unlink( $this->mUploadTempName );
 574                 wfRestoreWarnings();
 575                 if ( ! $success ) {
 576                         $wgOut->showFileDeleteError( $this->mUploadTempName );
 577                         return false;
 578                 } else {
 579                         return true;
 580                 }
 581         }
 582
 583         /* -------------------------------------------------------------- */
 584
 585         /**
 586          * Show some text and linkage on successful upload.
 587          * @access private
 588          */
 589         function showSuccess() {
 590                 global $wgUser, $wgOut, $wgContLang;
 591
 592                 $sk = $wgUser->getSkin();
 593                 $ilink = $sk->makeMediaLink( $this->mUploadSaveName, Image::imageUrl( $this->mUploadSaveName ) );
 594                 $dname = $wgContLang->getNsText( NS_IMAGE ) . ':'.$this->mUploadSaveName;
 595                 $dlink = $sk->makeKnownLink( $dname, $dname );
 596
 597                 $wgOut->addHTML( '<h2>' . wfMsgHtml( 'successfulupload' ) . "</h2>\n" );
 598                 $text = wfMsgWikiHtml( 'fileuploaded', $ilink, $dlink );
 599                 $wgOut->addHTML( $text );
 600                 $wgOut->returnToMain( false );
 601         }
 602
 603         /**
 604          * @param string $error as HTML
 605          * @access private
 606          */
 607         function uploadError( $error ) {
 608                 global $wgOut;
 609                 $wgOut->addHTML( "<h2>" . wfMsgHtml( 'uploadwarning' ) . "</h2>\n" );
 610                 $wgOut->addHTML( "<span class='error'>{$error}</span>\n" );
 611         }
 612
 613         /**
 614          * There's something wrong with this file, not enough to reject it
 615          * totally but we require manual intervention to save it for real.
 616          * Stash it away, then present a form asking to confirm or cancel.
 617          *
 618          * @param string $warning as HTML
 619          * @access private
 620          */
 621         function uploadWarning( $warning ) {
 622                 global $wgOut;
 623                 global $wgUseCopyrightUpload;
 624
 625                 $this->mSessionKey = $this->stashSession();
 626                 if( !$this->mSessionKey ) {
 627                         # Couldn't save file; an error has been displayed so let's go.
 628                         return;
 629                 }
 630
 631                 $wgOut->addHTML( "<h2>" . wfMsgHtml( 'uploadwarning' ) . "</h2>\n" );
 632                 $wgOut->addHTML( "<ul class='warning'>{$warning}</ul><br />\n" );
 633
 634                 $save = wfMsgHtml( 'savefile' );
 635                 $reupload = wfMsgHtml( 'reupload' );
 636                 $iw = wfMsgWikiHtml( 'ignorewarning' );
 637                 $reup = wfMsgWikiHtml( 'reuploaddesc' );
 638                 $titleObj = Title::makeTitle( NS_SPECIAL, 'Upload' );
 639                 $action = $titleObj->escapeLocalURL( 'action=submit' );
 640
 641                 if ( $wgUseCopyrightUpload )
 642                 {
 643                         $copyright =  "
 644         <input type='hidden' name='wpUploadCopyStatus' value=\"" . htmlspecialchars( $this->mUploadCopyStatus ) . "\" />
 645         <input type='hidden' name='wpUploadSource' value=\"" . htmlspecialchars( $this->mUploadSource ) . "\" />
 646         ";
 647                 } else {
 648                         $copyright = "";
 649                 }
 650
 651                 $wgOut->addHTML( "
 652         <form id='uploadwarning' method='post' enctype='multipart/form-data' action='$action'>
 653                 <input type='hidden' name='wpIgnoreWarning' value='1' />
 654                 <input type='hidden' name='wpSessionKey' value=\"" . htmlspecialchars( $this->mSessionKey ) . "\" />
 655                 <input type='hidden' name='wpUploadDescription' value=\"" . htmlspecialchars( $this->mUploadDescription ) . "\" />
 656                 <input type='hidden' name='wpLicense' value=\"" . htmlspecialchars( $this->mLicense ) . "\" />
 657                 <input type='hidden' name='wpDestFile' value=\"" . htmlspecialchars( $this->mDestFile ) . "\" />
 658                 <input type='hidden' name='wpWatchthis' value=\"" . htmlspecialchars( intval( $this->mWatchthis ) ) . "\" />
 659         {$copyright}
 660         <table border='0'>
 661                 <tr>
 662                         <tr>
 663                                 <td align='right'>
 664                                         <input tabindex='2' type='submit' name='wpUpload' value=\"$save\" />
 665                                 </td>
 666                                 <td align='left'>$iw</td>
 667                         </tr>
 668                         <tr>
 669                                 <td align='right'>
 670                                         <input tabindex='2' type='submit' name='wpReUpload' value=\"{$reupload}\" />
 671                                 </td>
 672                                 <td align='left'>$reup</td>
 673                         </tr>
 674                 </tr>
 675         </table></form>\n" );
 676         }
 677
 678         /**
 679          * Displays the main upload form, optionally with a highlighted
 680          * error message up at the top.
 681          *
 682          * @param string $msg as HTML
 683          * @access private
 684          */
 685         function mainUploadForm( $msg='' ) {
 686                 global $wgOut, $wgUser;
 687                 global $wgUseCopyrightUpload;
 688                 global $wgRequest, $wgAllowCopyUploads;
 689
 690                 $cols = intval($wgUser->getOption( 'cols' ));
 691                 $ew = $wgUser->getOption( 'editwidth' );
 692                 if ( $ew ) $ew = " style=\"width:100%\"";
 693                 else $ew = '';
 694
 695                 if ( '' != $msg ) {
 696                         $sub = wfMsgHtml( 'uploaderror' );
 697                         $wgOut->addHTML( "<h2>{$sub}</h2>\n" .
 698                           "<span class='error'>{$msg}</span>\n" );
 699                 }
 700                 $wgOut->addHTML( '<div id="uploadtext">' );
 701                 $wgOut->addWikiText( wfMsg( 'uploadtext' ) );
 702                 $wgOut->addHTML( '</div>' );
 703                 $sk = $wgUser->getSkin();
 704
 705
 706                 $sourcefilename = wfMsgHtml( 'sourcefilename' );
 707                 $destfilename = wfMsgHtml( 'destfilename' );
 708                 $summary = wfMsgWikiHtml( 'fileuploadsummary' );
 709
 710                 $licenses = new Licenses();
 711                 $license = wfMsgHtml( 'license' );
 712                 $nolicense = wfMsgHtml( 'nolicense' );
 713                 $licenseshtml = $licenses->getHtml();
 714
 715                 $ulb = wfMsgHtml( 'uploadbtn' );
 716
 717
 718                 $titleObj = Title::makeTitle( NS_SPECIAL, 'Upload' );
 719                 $action = $titleObj->escapeLocalURL();
 720
 721                 $encDestFile = htmlspecialchars( $this->mDestFile );
 722
 723                 $watchChecked = $wgUser->getOption( 'watchdefault' )
 724                         ? 'checked="checked"'
 725                         : '';
 726
 727                 // Fixme: this is a crappy form
 728                 if( $wgAllowCopyUploads && $wgRequest->getVal( 'source' ) == 'web' && $wgUser->isAllowed( 'upload_by_url' ) ) {
 729                         $sourcetype = 'text';
 730                         $source_comment = '<input type="hidden" name="wpSourceType" value="web" />' . wfMsgHtml( 'upload_source_url' );
 731                 } else {
 732                         $sourcetype = 'file';
 733                         $source_comment = '';
 734                 }
 735
 736                 $wgOut->addHTML( "
 737         <form id='upload' method='post' enctype='multipart/form-data' action=\"$action\">
 738                 <table border='0'>
 739                 <tr>
 740                         <td align='right'><label for='wpUploadFile'>{$sourcefilename}:</label></td>
 741                         <td align='left'>
 742                                 <input tabindex='1' type='{$sourcetype}' name='wpUploadFile' id='wpUploadFile' " . ($this->mDestFile?"":"onchange='fillDestFilename()' ") . "size='40' />{$source_comment}
 743                         </td>
 744                 </tr>
 745                 <tr>
 746                         <td align='right'><label for='wpDestFile'>{$destfilename}:</label></td>
 747                         <td align='left'>
 748                                 <input tabindex='2' type='text' name='wpDestFile' id='wpDestFile' size='40' value=\"$encDestFile\" />
 749                         </td>
 750                 </tr>
 751                 <tr>
 752                         <td align='right'><label for='wpUploadDescription'>{$summary}</label></td>
 753                         <td align='left'>
 754                                 <textarea tabindex='3' name='wpUploadDescription' id='wpUploadDescription' rows='6' cols='{$cols}'{$ew}>" . htmlspecialchars( $this->mUploadDescription ) . "</textarea>
 755                         </td>
 756                 </tr>
 757                 <tr>" );
 758
 759                 if ( $licenseshtml != '' ) {
 760                         global $wgStylePath;
 761                         $wgOut->addHTML( "
 762                         <td align='right'><label for='wpLicense'>$license:</label></td>
 763                         <td align='left'>
 764                                 <script type='text/javascript' src=\"$wgStylePath/common/upload.js\"></script>
 765                                 <select name='wpLicense' id='wpLicense' tabindex='4'
 766                                         onchange='licenseSelectorCheck()'>
 767                                         <option value=''>$nolicense</option>
 768                                         $licenseshtml
 769                                 </select>
 770                         </td>
 771                         </tr>
 772                         <tr>
 773                 ");
 774                 }
 775
 776                 if ( $wgUseCopyrightUpload ) {
 777                         $filestatus = wfMsgHtml ( 'filestatus' );
 778                         $copystatus =  htmlspecialchars( $this->mUploadCopyStatus );
 779                         $filesource = wfMsgHtml ( 'filesource' );
 780                         $uploadsource = htmlspecialchars( $this->mUploadSource );
 781
 782                         $wgOut->addHTML( "
 783                                 <td align='right' nowrap='nowrap'><label for='wpUploadCopyStatus'>$filestatus:</label></td>
 784                                 <td><input tabindex='5' type='text' name='wpUploadCopyStatus' id='wpUploadCopyStatus' value=\"$copystatus\" size='40' /></td>
 785                         </tr>
 786                         <tr>
 787                                 <td align='right'><label for='wpUploadCopyStatus'>$filesource:</label></td>
 788                                 <td><input tabindex='6' type='text' name='wpUploadSource' id='wpUploadCopyStatus' value=\"$uploadsource\" size='40' /></td>
 789                         </tr>
 790                         <tr>
 791                 ");
 792                 }
 793
 794
 795                 $wgOut->addHtml( "
 796                 <td></td>
 797                 <td>
 798                         <input tabindex='7' type='checkbox' name='wpWatchthis' id='wpWatchthis' $watchChecked value='true' />
 799                         <label for='wpWatchthis'>" . wfMsgHtml( 'watchthis' ) . "</label>
 800                         <input tabindex='8' type='checkbox' name='wpIgnoreWarning' id='wpIgnoreWarning' value='true' />
 801                         <label for='wpIgnoreWarning'>" . wfMsgHtml( 'ignorewarnings' ) . "</label>
 802                 </td>
 803         </tr>
 804         <tr>
 805
 806         </tr>
 807         <tr>
 808                 <td></td>
 809                 <td align='left'><input tabindex='9' type='submit' name='wpUpload' value=\"{$ulb}\" /></td>
 810         </tr>
 811
 812         <tr>
 813                 <td></td>
 814                 <td align='left'>
 815                 " );
 816                 $wgOut->addWikiText( wfMsgForContent( 'edittools' ) );
 817                 $wgOut->addHTML( "
 818                 </td>
 819         </tr>
 820
 821         </table>
 822         </form>" );
 823         }
 824
 825         /* -------------------------------------------------------------- */
 826
 827         /**
 828          * Split a file into a base name and all dot-delimited 'extensions'
 829          * on the end. Some web server configurations will fall back to
 830          * earlier pseudo-'extensions' to determine type and execute
 831          * scripts, so the blacklist needs to check them all.
 832          *
 833          * @return array
 834          */
 835         function splitExtensions( $filename ) {
 836                 $bits = explode( '.', $filename );
 837                 $basename = array_shift( $bits );
 838                 return array( $basename, $bits );
 839         }
 840
 841         /**
 842          * Perform case-insensitive match against a list of file extensions.
 843          * Returns true if the extension is in the list.
 844          *
 845          * @param string $ext
 846          * @param array $list
 847          * @return bool
 848          */
 849         function checkFileExtension( $ext, $list ) {
 850                 return in_array( strtolower( $ext ), $list );
 851         }
 852
 853         /**
 854          * Perform case-insensitive match against a list of file extensions.
 855          * Returns true if any of the extensions are in the list.
 856          *
 857          * @param array $ext
 858          * @param array $list
 859          * @return bool
 860          */
 861         function checkFileExtensionList( $ext, $list ) {
 862                 foreach( $ext as $e ) {
 863                         if( in_array( strtolower( $e ), $list ) ) {
 864                                 return true;
 865                         }
 866                 }
 867                 return false;
 868         }
 869
 870         /**
 871          * Verifies that it's ok to include the uploaded file
 872          *
 873          * @param string $tmpfile the full path of the temporary file to verify
 874          * @param string $extension The filename extension that the file is to be served with
 875          * @return mixed true of the file is verified, a WikiError object otherwise.
 876          */
 877         function verify( $tmpfile, $extension ) {
 878                 #magically determine mime type
 879                 $magic=& wfGetMimeMagic();
 880                 $mime= $magic->guessMimeType($tmpfile,false);
 881
 882                 $fname= "SpecialUpload::verify";
 883
 884                 #check mime type, if desired
 885                 global $wgVerifyMimeType;
 886                 if ($wgVerifyMimeType) {
 887
 888                         #check mime type against file extension
 889                         if( !$this->verifyExtension( $mime, $extension ) ) {
 890                                 return new WikiErrorMsg( 'uploadcorrupt' );
 891                         }
 892
 893                         #check mime type blacklist
 894                         global $wgMimeTypeBlacklist;
 895                         if( isset($wgMimeTypeBlacklist) && !is_null($wgMimeTypeBlacklist)
 896                                 && $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 897                                 return new WikiErrorMsg( 'badfiletype', htmlspecialchars( $mime ) );
 898                         }
 899                 }
 900
 901                 #check for htmlish code and javascript
 902                 if( $this->detectScript ( $tmpfile, $mime, $extension ) ) {
 903                         return new WikiErrorMsg( 'uploadscripted' );
 904                 }
 905
 906                 /**
 907                 * Scan the uploaded file for viruses
 908                 */
 909                 $virus= $this->detectVirus($tmpfile);
 910                 if ( $virus ) {
 911                         return new WikiErrorMsg( 'uploadvirus', htmlspecialchars($virus) );
 912                 }
 913
 914                 wfDebug( "$fname: all clear; passing.\n" );
 915                 return true;
 916         }
 917
 918         /**
 919          * Checks if the mime type of the uploaded file matches the file extension.
 920          *
 921          * @param string $mime the mime type of the uploaded file
 922          * @param string $extension The filename extension that the file is to be served with
 923          * @return bool
 924          */
 925         function verifyExtension( $mime, $extension ) {
 926                 $fname = 'SpecialUpload::verifyExtension';
 927
 928                 $magic =& wfGetMimeMagic();
 929
 930                 if ( ! $mime || $mime == 'unknown' || $mime == 'unknown/unknown' )
 931                         if ( ! $magic->isRecognizableExtension( $extension ) ) {
 932                                 wfDebug( "$fname: passing file with unknown detected mime type; unrecognized extension '$extension', can't verify\n" );
 933                                 return true;
 934                         } else {
 935                                 wfDebug( "$fname: rejecting file with unknown detected mime type; recognized extension '$extension', so probably invalid file\n" );
 936                                 return false;
 937                         }
 938
 939                 $match= $magic->isMatchingExtension($extension,$mime);
 940
 941                 if ($match===NULL) {
 942                         wfDebug( "$fname: no file extension known for mime type $mime, passing file\n" );
 943                         return true;
 944                 } elseif ($match===true) {
 945                         wfDebug( "$fname: mime type $mime matches extension $extension, passing file\n" );
 946
 947                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 948                         return true;
 949
 950                 } else {
 951                         wfDebug( "$fname: mime type $mime mismatches file extension $extension, rejecting file\n" );
 952                         return false;
 953                 }
 954         }
 955
 956         /** Heuristig for detecting files that *could* contain JavaScript instructions or
 957         * things that may look like HTML to a browser and are thus
 958         * potentially harmful. The present implementation will produce false positives in some situations.
 959         *
 960         * @param string $file Pathname to the temporary upload file
 961         * @param string $mime The mime type of the file
 962         * @param string $extension The extension of the file
 963         * @return bool true if the file contains something looking like embedded scripts
 964         */
 965         function detectScript($file, $mime, $extension) {
 966                 global $wgAllowTitlesInSVG;
 967
 968                 #ugly hack: for text files, always look at the entire file.
 969                 #For binarie field, just check the first K.
 970
 971                 if (strpos($mime,'text/')===0) $chunk = file_get_contents( $file );
 972                 else {
 973                         $fp = fopen( $file, 'rb' );
 974                         $chunk = fread( $fp, 1024 );
 975                         fclose( $fp );
 976                 }
 977
 978                 $chunk= strtolower( $chunk );
 979
 980                 if (!$chunk) return false;
 981
 982                 #decode from UTF-16 if needed (could be used for obfuscation).
 983                 if (substr($chunk,0,2)=="\xfe\xff") $enc= "UTF-16BE";
 984                 elseif (substr($chunk,0,2)=="\xff\xfe") $enc= "UTF-16LE";
 985                 else $enc= NULL;
 986
 987                 if ($enc) $chunk= iconv($enc,"ASCII//IGNORE",$chunk);
 988
 989                 $chunk= trim($chunk);
 990
 991                 #FIXME: convert from UTF-16 if necessarry!
 992
 993                 wfDebug("SpecialUpload::detectScript: checking for embedded scripts and HTML stuff\n");
 994
 995                 #check for HTML doctype
 996                 if (eregi("<!DOCTYPE *X?HTML",$chunk)) return true;
 997
 998                 /**
 999                 * Internet Explorer for Windows performs some really stupid file type
1000                 * autodetection which can cause it to interpret valid image files as HTML
1001                 * and potentially execute JavaScript, creating a cross-site scripting
1002                 * attack vectors.
1003                 *
1004                 * Apple's Safari browser also performs some unsafe file type autodetection
1005                 * which can cause legitimate files to be interpreted as HTML if the
1006                 * web server is not correctly configured to send the right content-type
1007                 * (or if you're really uploading plain text and octet streams!)
1008                 *
1009                 * Returns true if IE is likely to mistake the given file for HTML.
1010                 * Also returns true if Safari would mistake the given file for HTML
1011                 * when served with a generic content-type.
1012                 */
1013
1014                 $tags = array(
1015                         '<body',
1016                         '<head',
1017                         '<html',   #also in safari
1018                         '<img',
1019                         '<pre',
1020                         '<script', #also in safari
1021                         '<table'
1022                         );
1023                 if( ! $wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
1024                         $tags[] = '<title';
1025                 }
1026
1027                 foreach( $tags as $tag ) {
1028                         if( false !== strpos( $chunk, $tag ) ) {
1029                                 return true;
1030                         }
1031                 }
1032
1033                 /*
1034                 * look for javascript
1035                 */
1036
1037                 #resolve entity-refs to look at attributes. may be harsh on big files... cache result?
1038                 $chunk = Sanitizer::decodeCharReferences( $chunk );
1039
1040                 #look for script-types
1041                 if (preg_match("!type\s*=\s*['\"]?\s*(\w*/)?(ecma|java)!sim",$chunk)) return true;
1042
1043                 #look for html-style script-urls
1044                 if (preg_match("!(href|src|data)\s*=\s*['\"]?\s*(ecma|java)script:!sim",$chunk)) return true;
1045
1046                 #look for css-style script-urls
1047                 if (preg_match("!url\s*\(\s*['\"]?\s*(ecma|java)script:!sim",$chunk)) return true;
1048
1049                 wfDebug("SpecialUpload::detectScript: no scripts found\n");
1050                 return false;
1051         }
1052
1053         /** Generic wrapper function for a virus scanner program.
1054         * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1055         * $wgAntivirusRequired may be used to deny upload if the scan fails.
1056         *
1057         * @param string $file Pathname to the temporary upload file
1058         * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
1059         *         or a string containing feedback from the virus scanner if a virus was found.
1060         *         If textual feedback is missing but a virus was found, this function returns true.
1061         */
1062         function detectVirus($file) {
1063                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1064
1065                 $fname= "SpecialUpload::detectVirus";
1066
1067                 if (!$wgAntivirus) { #disabled?
1068                         wfDebug("$fname: virus scanner disabled\n");
1069
1070                         return NULL;
1071                 }
1072
1073                 if (!$wgAntivirusSetup[$wgAntivirus]) {
1074                         wfDebug("$fname: unknown virus scanner: $wgAntivirus\n");
1075
1076                         $wgOut->addHTML( "<div class='error'>Bad configuration: unknown virus scanner: <i>$wgAntivirus</i></div>\n" ); #LOCALIZE
1077
1078                         return "unknown antivirus: $wgAntivirus";
1079                 }
1080
1081                 #look up scanner configuration
1082                 $virus_scanner= $wgAntivirusSetup[$wgAntivirus]["command"]; #command pattern
1083                 $virus_scanner_codes= $wgAntivirusSetup[$wgAntivirus]["codemap"]; #exit-code map
1084                 $msg_pattern= $wgAntivirusSetup[$wgAntivirus]["messagepattern"]; #message pattern
1085
1086                 $scanner= $virus_scanner; #copy, so we can resolve the pattern
1087
1088                 if (strpos($scanner,"%f")===false) $scanner.= " ".wfEscapeShellArg($file); #simple pattern: append file to scan
1089                 else $scanner= str_replace("%f",wfEscapeShellArg($file),$scanner); #complex pattern: replace "%f" with file to scan
1090
1091                 wfDebug("$fname: running virus scan: $scanner \n");
1092
1093                 #execute virus scanner
1094                 $code= false;
1095
1096                 #NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1097                 #      that does not seem to be worth the pain.
1098                 #      Ask me (Duesentrieb) about it if it's ever needed.
1099                 if (wfIsWindows()) exec("$scanner",$output,$code);
1100                 else exec("$scanner 2>&1",$output,$code);
1101
1102                 $exit_code= $code; #remeber for user feedback
1103
1104                 if ($virus_scanner_codes) { #map exit code to AV_xxx constants.
1105                         if (isset($virus_scanner_codes[$code])) $code= $virus_scanner_codes[$code]; #explicite mapping
1106                         else if (isset($virus_scanner_codes["*"])) $code= $virus_scanner_codes["*"]; #fallback mapping
1107                 }
1108
1109                 if ($code===AV_SCAN_FAILED) { #scan failed (code was mapped to false by $virus_scanner_codes)
1110                         wfDebug("$fname: failed to scan $file (code $exit_code).\n");
1111
1112                         if ($wgAntivirusRequired) return "scan failed (code $exit_code)";
1113                         else return NULL;
1114                 }
1115                 else if ($code===AV_SCAN_ABORTED) { #scan failed because filetype is unknown (probably imune)
1116                         wfDebug("$fname: unsupported file type $file (code $exit_code).\n");
1117                         return NULL;
1118                 }
1119                 else if ($code===AV_NO_VIRUS) {
1120                         wfDebug("$fname: file passed virus scan.\n");
1121                         return false; #no virus found
1122                 }
1123                 else {
1124                         $output= join("\n",$output);
1125                         $output= trim($output);
1126
1127                         if (!$output) $output= true; #if ther's no output, return true
1128                         else if ($msg_pattern) {
1129                                 $groups= array();
1130                                 if (preg_match($msg_pattern,$output,$groups)) {
1131                                         if ($groups[1]) $output= $groups[1];
1132                                 }
1133                         }
1134
1135                         wfDebug("$fname: FOUND VIRUS! scanner feedback: $output");
1136                         return $output;
1137                 }
1138         }
1139
1140         /**
1141          * Check if the temporary file is MacBinary-encoded, as some uploads
1142          * from Internet Explorer on Mac OS Classic and Mac OS X will be.
1143          * If so, the data fork will be extracted to a second temporary file,
1144          * which will then be checked for validity and either kept or discarded.
1145          *
1146          * @access private
1147          */
1148         function checkMacBinary() {
1149                 $macbin = new MacBinary( $this->mUploadTempName );
1150                 if( $macbin->isValid() ) {
1151                         $dataFile = tempnam( wfTempDir(), "WikiMacBinary" );
1152                         $dataHandle = fopen( $dataFile, 'wb' );
1153
1154                         wfDebug( "SpecialUpload::checkMacBinary: Extracting MacBinary data fork to $dataFile\n" );
1155                         $macbin->extractData( $dataHandle );
1156
1157                         $this->mUploadTempName = $dataFile;
1158                         $this->mUploadSize = $macbin->dataForkLength();
1159
1160                         // We'll have to manually remove the new file if it's not kept.
1161                         $this->mRemoveTempFile = true;
1162                 }
1163                 $macbin->close();
1164         }
1165
1166         /**
1167          * If we've modified the upload file we need to manually remove it
1168          * on exit to clean up.
1169          * @access private
1170          */
1171         function cleanupTempFile() {
1172                 if( $this->mRemoveTempFile && file_exists( $this->mUploadTempName ) ) {
1173                         wfDebug( "SpecialUpload::cleanupTempFile: Removing temporary file $this->mUploadTempName\n" );
1174                         unlink( $this->mUploadTempName );
1175                 }
1176         }
1177
1178         /**
1179          * Check if there's an overwrite conflict and, if so, if restrictions
1180          * forbid this user from performing the upload.
1181          *
1182          * @return mixed true on success, WikiError on failure
1183          * @access private
1184          */
1185         function checkOverwrite( $name ) {
1186                 $img = Image::newFromName( $name );
1187                 if( is_null( $img ) ) {
1188                         // Uh... this shouldn't happen ;)
1189                         // But if it does, fall through to previous behavior
1190                         return false;
1191                 }
1192
1193                 $error = '';
1194                 if( $img->exists() ) {
1195                         global $wgUser, $wgOut;
1196                         if( $img->isLocal() ) {
1197                                 if( !$wgUser->isAllowed( 'reupload' ) ) {
1198                                         $error = 'fileexists-forbidden';
1199                                 }
1200                         } else {
1201                                 if( !$wgUser->isAllowed( 'reupload' ) ||
1202                                     !$wgUser->isAllowed( 'reupload-shared' ) ) {
1203                                         $error = "fileexists-shared-forbidden";
1204                                 }
1205                         }
1206                 }
1207
1208                 if( $error ) {
1209                         $errorText = wfMsg( $error, wfEscapeWikiText( $img->getName() ) );
1210                         return new WikiError( $wgOut->parse( $errorText ) );
1211                 }
1212
1213                 // Rockin', go ahead and upload
1214                 return true;
1215         }
1216
1217 }
1218
1219
1220 ?>