includes/SpecialUpload.php

   1 <?php
   2 /**
   3  *
   4  * @package MediaWiki
   5  * @subpackage SpecialPage
   6  */
   7
   8 /**
   9  *
  10  */
  11 require_once( 'Image.php' );
  12 require_once( 'MacBinary.php' );
  13
  14 /**
  15  * Entry point
  16  */
  17 function wfSpecialUpload() {
  18         global $wgRequest;
  19         $form = new UploadForm( $wgRequest );
  20         $form->execute();
  21 }
  22
  23 /**
  24  *
  25  * @package MediaWiki
  26  * @subpackage SpecialPage
  27  */
  28 class UploadForm {
  29         /**#@+
  30          * @access private
  31          */
  32         var $mUploadFile, $mUploadDescription, $mIgnoreWarning;
  33         var $mUploadSaveName, $mUploadTempName, $mUploadSize, $mUploadOldVersion;
  34         var $mUploadCopyStatus, $mUploadSource, $mReUpload, $mAction, $mUpload;
  35         var $mOname, $mSessionKey, $mStashed, $mDestFile, $mRemoveTempFile;
  36         /**#@-*/
  37
  38         /**
  39          * Constructor : initialise object
  40          * Get data POSTed through the form and assign them to the object
  41          * @param $request Data posted.
  42          */
  43         function UploadForm( &$request ) {
  44                 $this->mDestFile          = $request->getText( 'wpDestFile' );
  45
  46                 if( !$request->wasPosted() ) {
  47                         # GET requests just give the main form; no data except wpDestfile.
  48                         return;
  49                 }
  50
  51                 $this->mIgnoreWarning     = $request->getCheck( 'wpIgnoreWarning');
  52                 $this->mReUpload          = $request->getCheck( 'wpReUpload' );
  53                 $this->mUpload            = $request->getCheck( 'wpUpload' );
  54
  55                 $this->mUploadDescription = $request->getText( 'wpUploadDescription' );
  56                 $this->mUploadCopyStatus  = $request->getText( 'wpUploadCopyStatus' );
  57                 $this->mUploadSource      = $request->getText( 'wpUploadSource');
  58
  59                 $this->mAction            = $request->getVal( 'action' );
  60
  61                 $this->mSessionKey        = $request->getInt( 'wpSessionKey' );
  62                 if( !empty( $this->mSessionKey ) &&
  63                         isset( $_SESSION['wsUploadData'][$this->mSessionKey] ) ) {
  64                         /**
  65                          * Confirming a temporarily stashed upload.
  66                          * We don't want path names to be forged, so we keep
  67                          * them in the session on the server and just give
  68                          * an opaque key to the user agent.
  69                          */
  70                         $data = $_SESSION['wsUploadData'][$this->mSessionKey];
  71                         $this->mUploadTempName   = $data['mUploadTempName'];
  72                         $this->mUploadSize       = $data['mUploadSize'];
  73                         $this->mOname            = $data['mOname'];
  74                         $this->mStashed          = true;
  75                         $this->mRemoveTempFile   = false;
  76                 } else {
  77                         /**
  78                          *Check for a newly uploaded file.
  79                          */
  80                         $this->mUploadTempName = $request->getFileTempName( 'wpUploadFile' );
  81                         $this->mUploadSize     = $request->getFileSize( 'wpUploadFile' );
  82                         $this->mOname          = $request->getFileName( 'wpUploadFile' );
  83                         $this->mSessionKey     = false;
  84                         $this->mStashed        = false;
  85                         $this->mRemoveTempFile = false; // PHP will handle this
  86                 }
  87         }
  88
  89         /**
  90          * Start doing stuff
  91          * @access public
  92          */
  93         function execute() {
  94                 global $wgUser, $wgOut;
  95                 global $wgEnableUploads, $wgUploadDirectory;
  96
  97                 /** Show an error message if file upload is disabled */
  98                 if( ! $wgEnableUploads ) {
  99                         $wgOut->addWikiText( wfMsg( 'uploaddisabled' ) );
 100                         return;
 101                 }
 102
 103                 /** Various rights checks */
 104                 if( !$wgUser->isAllowed( 'upload' ) || $wgUser->isBlocked() ) {
 105                         $wgOut->errorpage( 'uploadnologin', 'uploadnologintext' );
 106                         return;
 107                 }
 108                 if( wfReadOnly() ) {
 109                         $wgOut->readOnlyPage();
 110                         return;
 111                 }
 112
 113                 /** Check if the image directory is writeable, this is a common mistake */
 114                 if ( !is_writeable( $wgUploadDirectory ) ) {
 115                         $wgOut->addWikiText( wfMsg( 'upload_directory_read_only', $wgUploadDirectory ) );
 116                         return;
 117                 }
 118
 119                 if( $this->mReUpload ) {
 120                         $this->unsaveUploadedFile();
 121                         $this->mainUploadForm();
 122                 } else if ( 'submit' == $this->mAction || $this->mUpload ) {
 123                         $this->processUpload();
 124                 } else {
 125                         $this->mainUploadForm();
 126                 }
 127
 128                 $this->cleanupTempFile();
 129         }
 130
 131         /* -------------------------------------------------------------- */
 132
 133         /**
 134          * Really do the upload
 135          * Checks are made in SpecialUpload::execute()
 136          * @access private
 137          */
 138         function processUpload() {
 139                 global $wgUser, $wgOut, $wgLang, $wgContLang;
 140                 global $wgUploadDirectory;
 141                 global $wgUseCopyrightUpload, $wgCheckCopyrightUpload;
 142
 143                 /**
 144                  * If there was no filename or a zero size given, give up quick.
 145                  */
 146                 if( trim( $this->mOname ) == '' || empty( $this->mUploadSize ) ) {
 147                         return $this->mainUploadForm('<li>'.wfMsg( 'emptyfile' ).'</li>');
 148                 }
 149
 150                 # Chop off any directories in the given filename
 151                 if ( $this->mDestFile ) {
 152                         $basename = basename( $this->mDestFile );
 153                 } else {
 154                         $basename = basename( $this->mOname );
 155                 }
 156
 157                 /**
 158                  * We'll want to blacklist against *any* 'extension', and use
 159                  * only the final one for the whitelist.
 160                  */
 161                 list( $partname, $ext ) = $this->splitExtensions( $basename );
 162                 if( count( $ext ) ) {
 163                         $finalExt = $ext[count( $ext ) - 1];
 164                 } else {
 165                         $finalExt = '';
 166                 }
 167                 $fullExt = implode( '.', $ext );
 168
 169                 if ( strlen( $partname ) < 3 ) {
 170                         $this->mainUploadForm( wfMsg( 'minlength' ) );
 171                         return;
 172                 }
 173
 174                 /**
 175                  * Filter out illegal characters, and try to make a legible name
 176                  * out of it. We'll strip some silently that Title would die on.
 177                  */
 178                 $filtered = preg_replace ( "/[^".Title::legalChars()."]|:/", '-', $basename );
 179                 $nt = Title::newFromText( $filtered );
 180                 if( is_null( $nt ) ) {
 181                         return $this->uploadError( wfMsg( 'illegalfilename', htmlspecialchars( $filtered ) ) );
 182                 }
 183                 $nt =& Title::makeTitle( NS_IMAGE, $nt->getDBkey() );
 184                 $this->mUploadSaveName = $nt->getDBkey();
 185
 186                 /**
 187                  * If the image is protected, non-sysop users won't be able
 188                  * to modify it by uploading a new revision.
 189                  */
 190                 if( !$nt->userCanEdit() ) {
 191                         return $this->uploadError( wfMsg( 'protectedpage' ) );
 192                 }
 193
 194                 /* Don't allow users to override the blacklist (check file extension) */
 195                 global $wgStrictFileExtensions;
 196                 global $wgFileExtensions, $wgFileBlacklist;
 197                 if( $this->checkFileExtensionList( $ext, $wgFileBlacklist ) ||
 198                         ($wgStrictFileExtensions &&
 199                                 !$this->checkFileExtension( $finalExt, $wgFileExtensions ) ) ) {
 200                         return $this->uploadError( wfMsg( 'badfiletype', htmlspecialchars( $fullExt ) ) );
 201                 }
 202
 203                 /**
 204                  * Look at the contents of the file; if we can recognize the
 205                  * type but it's corrupt or data of the wrong type, we should
 206                  * probably not accept it.
 207                  */
 208                 if( !$this->mStashed ) {
 209                         $this->checkMacBinary();
 210                         $veri = $this->verify( $this->mUploadTempName, $finalExt );
 211
 212                         if( $veri !== true ) { //it's a wiki error...
 213                                 return $this->uploadError( $veri->toString() );
 214                         }
 215                 }
 216
 217                 /**
 218                  * Check for non-fatal conditions
 219                  */
 220                 if ( ! $this->mIgnoreWarning ) {
 221                         $warning = '';
 222                         if( $this->mUploadSaveName != ucfirst( $filtered ) ) {
 223                                 $warning .=  '<li>'.wfMsg( 'badfilename', htmlspecialchars( $this->mUploadSaveName ) ).'</li>';
 224                         }
 225
 226                         global $wgCheckFileExtensions;
 227                         if ( $wgCheckFileExtensions ) {
 228                                 if ( ! $this->checkFileExtension( $finalExt, $wgFileExtensions ) ) {
 229                                         $warning .= '<li>'.wfMsg( 'badfiletype', htmlspecialchars( $fullExt ) ).'</li>';
 230                                 }
 231                         }
 232
 233                         global $wgUploadSizeWarning;
 234                         if ( $wgUploadSizeWarning && ( $this->mUploadSize > $wgUploadSizeWarning ) ) {
 235                                 # TODO: Format $wgUploadSizeWarning to something that looks better than the raw byte
 236                                 # value, perhaps add GB,MB and KB suffixes?
 237                                 $warning .= '<li>'.wfMsg( 'largefile', $wgUploadSizeWarning, $this->mUploadSize ).'</li>';
 238                         }
 239                         if ( $this->mUploadSize == 0 ) {
 240                                 $warning .= '<li>'.wfMsg( 'emptyfile' ).'</li>';
 241                         }
 242
 243                         if( $nt->getArticleID() ) {
 244                                 global $wgUser;
 245                                 $sk = $wgUser->getSkin();
 246                                 $dlink = $sk->makeKnownLinkObj( $nt );
 247                                 $warning .= '<li>'.wfMsg( 'fileexists', $dlink ).'</li>';
 248                         }
 249
 250                         if( $warning != '' ) {
 251                                 /**
 252                                  * Stash the file in a temporary location; the user can choose
 253                                  * to let it through and we'll complete the upload then.
 254                                  */
 255                                 return $this->uploadWarning($warning);
 256                         }
 257                 }
 258
 259                 /**
 260                  * Try actually saving the thing...
 261                  * It will show an error form on failure.
 262                  */
 263                 $hasBeenMunged = !empty( $this->mSessionKey ) || $this->mRemoveTempFile;
 264                 if( $this->saveUploadedFile( $this->mUploadSaveName,
 265                                              $this->mUploadTempName,
 266                                              $hasBeenMunged ) ) {
 267                         /**
 268                          * Update the upload log and create the description page
 269                          * if it's a new file.
 270                          */
 271                         $img = Image::newFromName( $this->mUploadSaveName );
 272                         $success = $img->recordUpload( $this->mUploadOldVersion,
 273                                                         $this->mUploadDescription,
 274                                                         $this->mUploadCopyStatus,
 275                                                         $this->mUploadSource );
 276
 277                         if ( $success ) {
 278                                 $this->showSuccess();
 279                         } else {
 280                                 // Image::recordUpload() fails if the image went missing, which is
 281                                 // unlikely, hence the lack of a specialised message
 282                                 $wgOut->fileNotFoundError( $this->mUploadSaveName );
 283                         }
 284                 }
 285         }
 286
 287         /**
 288          * Move the uploaded file from its temporary location to the final
 289          * destination. If a previous version of the file exists, move
 290          * it into the archive subdirectory.
 291          *
 292          * @todo If the later save fails, we may have disappeared the original file.
 293          *
 294          * @param string $saveName
 295          * @param string $tempName full path to the temporary file
 296          * @param bool $useRename if true, doesn't check that the source file
 297          *                        is a PHP-managed upload temporary
 298          */
 299         function saveUploadedFile( $saveName, $tempName, $useRename = false ) {
 300                 global $wgUploadDirectory, $wgOut;
 301
 302                 $fname= "SpecialUpload::saveUploadedFile";
 303
 304                 $dest = wfImageDir( $saveName );
 305                 $archive = wfImageArchiveDir( $saveName );
 306                 $this->mSavedFile = "{$dest}/{$saveName}";
 307
 308                 if( is_file( $this->mSavedFile ) ) {
 309                         $this->mUploadOldVersion = gmdate( 'YmdHis' ) . "!{$saveName}";
 310                         wfSuppressWarnings();
 311                         $success = rename( $this->mSavedFile, "${archive}/{$this->mUploadOldVersion}" );
 312                         wfRestoreWarnings();
 313
 314                         if( ! $success ) {
 315                                 $wgOut->fileRenameError( $this->mSavedFile,
 316                                   "${archive}/{$this->mUploadOldVersion}" );
 317                                 return false;
 318                         }
 319                         else wfDebug("$fname: moved file ".$this->mSavedFile." to ${archive}/{$this->mUploadOldVersion}\n");
 320                 }
 321                 else {
 322                         $this->mUploadOldVersion = '';
 323                 }
 324
 325                 wfSuppressWarnings();
 326                 $success = $useRename
 327                         ? rename( $tempName, $this->mSavedFile )
 328                         : move_uploaded_file( $tempName, $this->mSavedFile );
 329                 wfRestoreWarnings();
 330
 331                 if( ! $success ) {
 332                         $wgOut->fileCopyError( $tempName, $this->mSavedFile );
 333                         return false;
 334                 } else {
 335                         wfDebug("$fname: wrote tempfile $tempName to ".$this->mSavedFile."\n");
 336                 }
 337
 338                 chmod( $this->mSavedFile, 0644 );
 339                 return true;
 340         }
 341
 342         /**
 343          * Stash a file in a temporary directory for later processing
 344          * after the user has confirmed it.
 345          *
 346          * If the user doesn't explicitly cancel or accept, these files
 347          * can accumulate in the temp directory.
 348          *
 349          * @param string $saveName - the destination filename
 350          * @param string $tempName - the source temporary file to save
 351          * @return string - full path the stashed file, or false on failure
 352          * @access private
 353          */
 354         function saveTempUploadedFile( $saveName, $tempName ) {
 355                 global $wgOut;
 356                 $archive = wfImageArchiveDir( $saveName, 'temp' );
 357                 $stash = $archive . '/' . gmdate( "YmdHis" ) . '!' . $saveName;
 358
 359                 $success = $this->mRemoveTempFile
 360                         ? rename( $tempName, $stash )
 361                         : move_uploaded_file( $tempName, $stash );
 362                 if ( !$success ) {
 363                         $wgOut->fileCopyError( $tempName, $stash );
 364                         return false;
 365                 }
 366
 367                 return $stash;
 368         }
 369
 370         /**
 371          * Stash a file in a temporary directory for later processing,
 372          * and save the necessary descriptive info into the session.
 373          * Returns a key value which will be passed through a form
 374          * to pick up the path info on a later invocation.
 375          *
 376          * @return int
 377          * @access private
 378          */
 379         function stashSession() {
 380                 $stash = $this->saveTempUploadedFile(
 381                         $this->mUploadSaveName, $this->mUploadTempName );
 382
 383                 if( !$stash ) {
 384                         # Couldn't save the file.
 385                         return false;
 386                 }
 387
 388                 $key = mt_rand( 0, 0x7fffffff );
 389                 $_SESSION['wsUploadData'][$key] = array(
 390                         'mUploadTempName' => $stash,
 391                         'mUploadSize'     => $this->mUploadSize,
 392                         'mOname'          => $this->mOname );
 393                 return $key;
 394         }
 395
 396         /**
 397          * Remove a temporarily kept file stashed by saveTempUploadedFile().
 398          * @access private
 399          */
 400         function unsaveUploadedFile() {
 401                 wfSuppressWarnings();
 402                 $success = unlink( $this->mUploadTempName );
 403                 wfRestoreWarnings();
 404                 if ( ! $success ) {
 405                         $wgOut->fileDeleteError( $this->mUploadTempName );
 406                 }
 407         }
 408
 409         /* -------------------------------------------------------------- */
 410
 411         /**
 412          * Show some text and linkage on successful upload.
 413          * @access private
 414          */
 415         function showSuccess() {
 416                 global $wgUser, $wgOut, $wgContLang;
 417
 418                 $sk = $wgUser->getSkin();
 419                 $ilink = $sk->makeMediaLink( $this->mUploadSaveName, Image::imageUrl( $this->mUploadSaveName ) );
 420                 $dname = $wgContLang->getNsText( NS_IMAGE ) . ':'.$this->mUploadSaveName;
 421                 $dlink = $sk->makeKnownLink( $dname, $dname );
 422
 423                 $wgOut->addHTML( '<h2>' . wfMsg( 'successfulupload' ) . "</h2>\n" );
 424                 $text = wfMsg( 'fileuploaded', $ilink, $dlink );
 425                 $wgOut->addHTML( $text );
 426                 $wgOut->returnToMain( false );
 427         }
 428
 429         /**
 430          * @param string $error as HTML
 431          * @access private
 432          */
 433         function uploadError( $error ) {
 434                 global $wgOut;
 435                 $sub = wfMsg( 'uploadwarning' );
 436                 $wgOut->addHTML( "<h2>{$sub}</h2>\n" );
 437                 $wgOut->addHTML( "<h4 class='error'>{$error}</h4>\n" );
 438         }
 439
 440         /**
 441          * There's something wrong with this file, not enough to reject it
 442          * totally but we require manual intervention to save it for real.
 443          * Stash it away, then present a form asking to confirm or cancel.
 444          *
 445          * @param string $warning as HTML
 446          * @access private
 447          */
 448         function uploadWarning( $warning ) {
 449                 global $wgOut, $wgUser, $wgLang, $wgUploadDirectory, $wgRequest;
 450                 global $wgUseCopyrightUpload;
 451
 452                 $this->mSessionKey = $this->stashSession();
 453                 if( !$this->mSessionKey ) {
 454                         # Couldn't save file; an error has been displayed so let's go.
 455                         return;
 456                 }
 457
 458                 $sub = wfMsg( 'uploadwarning' );
 459                 $wgOut->addHTML( "<h2>{$sub}</h2>\n" );
 460                 $wgOut->addHTML( "<ul class='warning'>{$warning}</ul><br />\n" );
 461
 462                 $save = wfMsg( 'savefile' );
 463                 $reupload = wfMsg( 'reupload' );
 464                 $iw = wfMsg( 'ignorewarning' );
 465                 $reup = wfMsg( 'reuploaddesc' );
 466                 $titleObj = Title::makeTitle( NS_SPECIAL, 'Upload' );
 467                 $action = $titleObj->escapeLocalURL( 'action=submit' );
 468
 469                 if ( $wgUseCopyrightUpload )
 470                 {
 471                         $copyright =  "
 472         <input type='hidden' name='wpUploadCopyStatus' value=\"" . htmlspecialchars( $this->mUploadCopyStatus ) . "\" />
 473         <input type='hidden' name='wpUploadSource' value=\"" . htmlspecialchars( $this->mUploadSource ) . "\" />
 474         ";
 475                 } else {
 476                         $copyright = "";
 477                 }
 478
 479                 $wgOut->addHTML( "
 480         <form id='uploadwarning' method='post' enctype='multipart/form-data' action='$action'>
 481                 <input type='hidden' name='wpIgnoreWarning' value='1' />
 482                 <input type='hidden' name='wpSessionKey' value=\"" . htmlspecialchars( $this->mSessionKey ) . "\" />
 483                 <input type='hidden' name='wpUploadDescription' value=\"" . htmlspecialchars( $this->mUploadDescription ) . "\" />
 484                 <input type='hidden' name='wpDestFile' value=\"" . htmlspecialchars( $this->mDestFile ) . "\" />
 485         {$copyright}
 486         <table border='0'>
 487                 <tr>
 488                         <tr>
 489                                 <td align='right'>
 490                                         <input tabindex='2' type='submit' name='wpUpload' value='$save' />
 491                                 </td>
 492                                 <td align='left'>$iw</td>
 493                         </tr>
 494                         <tr>
 495                                 <td align='right'>
 496                                         <input tabindex='2' type='submit' name='wpReUpload' value='{$reupload}' />
 497                                 </td>
 498                                 <td align='left'>$reup</td>
 499                         </tr>
 500                 </tr>
 501         </table></form>\n" );
 502         }
 503
 504         /**
 505          * Displays the main upload form, optionally with a highlighted
 506          * error message up at the top.
 507          *
 508          * @param string $msg as HTML
 509          * @access private
 510          */
 511         function mainUploadForm( $msg='' ) {
 512                 global $wgOut, $wgUser, $wgLang, $wgUploadDirectory, $wgRequest;
 513                 global $wgUseCopyrightUpload;
 514
 515                 $cols = intval($wgUser->getOption( 'cols' ));
 516                 $ew = $wgUser->getOption( 'editwidth' );
 517                 if ( $ew ) $ew = " style=\"width:100%\"";
 518                 else $ew = '';
 519
 520                 if ( '' != $msg ) {
 521                         $sub = wfMsg( 'uploaderror' );
 522                         $wgOut->addHTML( "<h2>{$sub}</h2>\n" .
 523                           "<h4 class='error'>{$msg}</h4>\n" );
 524                 }
 525                 $wgOut->addWikiText( wfMsg( 'uploadtext' ) );
 526                 $sk = $wgUser->getSkin();
 527
 528
 529                 $sourcefilename = wfMsg( 'sourcefilename' );
 530                 $destfilename = wfMsg( 'destfilename' );
 531
 532                 $fd = wfMsg( 'filedesc' );
 533                 $ulb = wfMsg( 'uploadbtn' );
 534
 535                 $iw = wfMsg( 'ignorewarning' );
 536
 537                 $titleObj = Title::makeTitle( NS_SPECIAL, 'Upload' );
 538                 $action = $titleObj->escapeLocalURL();
 539
 540                 $encDestFile = htmlspecialchars( $this->mDestFile );
 541                 $source = null;
 542
 543                 if ( $wgUseCopyrightUpload )
 544                   {
 545                         $source = "
 546         <td align='right' nowrap='nowrap'>" . wfMsg ( 'filestatus' ) . ":</td>
 547         <td><input tabindex='3' type='text' name=\"wpUploadCopyStatus\" value=\"" .
 548         htmlspecialchars($this->mUploadCopyStatus). "\" size='40' /></td>
 549         </tr><tr>
 550         <td align='right'>". wfMsg ( 'filesource' ) . ":</td>
 551         <td><input tabindex='4' type='text' name='wpUploadSource' value=\"" .
 552         htmlspecialchars($this->mUploadSource). "\" size='40' /></td>
 553         " ;
 554                   }
 555
 556                 $wgOut->addHTML( "
 557         <form id='upload' method='post' enctype='multipart/form-data' action=\"$action\">
 558         <table border='0'><tr>
 559
 560         <td align='right'>{$sourcefilename}:</td><td align='left'>
 561         <input tabindex='1' type='file' name='wpUploadFile' id='wpUploadFile' onchange='fillDestFilename()' size='40' />
 562         </td></tr><tr>
 563
 564         <td align='right'>{$destfilename}:</td><td align='left'>
 565         <input tabindex='1' type='text' name='wpDestFile' id='wpDestFile' size='40' value=\"$encDestFile\" />
 566         </td></tr><tr>
 567
 568         <td align='right'>{$fd}:</td><td align='left'>
 569         <textarea tabindex='2' name='wpUploadDescription' rows='6' cols='{$cols}'{$ew}>"
 570           . htmlspecialchars( $this->mUploadDescription ) .
 571         "</textarea>
 572         </td></tr><tr>
 573         {$source}
 574         </tr>
 575         <tr><td></td><td align='left'>
 576         <input tabindex='5' type='submit' name='wpUpload' value=\"{$ulb}\" />
 577         </td></tr></table></form>\n" );
 578         }
 579
 580         /* -------------------------------------------------------------- */
 581
 582         /**
 583          * Split a file into a base name and all dot-delimited 'extensions'
 584          * on the end. Some web server configurations will fall back to
 585          * earlier pseudo-'extensions' to determine type and execute
 586          * scripts, so the blacklist needs to check them all.
 587          *
 588          * @return array
 589          */
 590         function splitExtensions( $filename ) {
 591                 $bits = explode( '.', $filename );
 592                 $basename = array_shift( $bits );
 593                 return array( $basename, $bits );
 594         }
 595
 596         /**
 597          * Perform case-insensitive match against a list of file extensions.
 598          * Returns true if the extension is in the list.
 599          *
 600          * @param string $ext
 601          * @param array $list
 602          * @return bool
 603          */
 604         function checkFileExtension( $ext, $list ) {
 605                 return in_array( strtolower( $ext ), $list );
 606         }
 607
 608         /**
 609          * Perform case-insensitive match against a list of file extensions.
 610          * Returns true if any of the extensions are in the list.
 611          *
 612          * @param array $ext
 613          * @param array $list
 614          * @return bool
 615          */
 616         function checkFileExtensionList( $ext, $list ) {
 617                 foreach( $ext as $e ) {
 618                         if( in_array( strtolower( $e ), $list ) ) {
 619                                 return true;
 620                         }
 621                 }
 622                 return false;
 623         }
 624
 625         /**
 626          * Verifies that it's ok to include the uploaded file
 627          *
 628          * @param string $tmpfile the full path of the temporary file to verify
 629          * @param string $extension The filename extension that the file is to be served with
 630          * @return mixed true of the file is verified, a WikiError object otherwise.
 631          */
 632         function verify( $tmpfile, $extension ) {
 633                 #magically determine mime type
 634                 $magic=& wfGetMimeMagic();
 635                 $mime= $magic->guessMimeType($tmpfile,false);
 636
 637                 $fname= "SpecialUpload::verify";
 638
 639                 #check mime type, if desired
 640                 global $wgVerifyMimeType;
 641                 if ($wgVerifyMimeType) {
 642
 643                         #check mime type against file extension
 644                         if( !$this->verifyExtension( $mime, $extension ) ) {
 645                                 return new WikiErrorMsg( 'uploadcorrupt' );
 646                         }
 647
 648                         #check mime type blacklist
 649                         global $wgMimeTypeBlacklist;
 650                         if( isset($wgMimeTypeBlacklist) && !is_null($wgMimeTypeBlacklist)
 651                                 && $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 652                                 return new WikiErrorMsg( 'badfiletype', htmlspecialchars( $mime ) );
 653                         }
 654                 }
 655
 656                 #check for htmlish code and javascript
 657                 if( $this->detectScript ( $tmpfile, $mime ) ) {
 658                         return new WikiErrorMsg( 'uploadscripted' );
 659                 }
 660
 661                 /**
 662                 * Scan the uploaded file for viruses
 663                 */
 664                 $virus= $this->detectVirus($tmpfile);
 665                 if ( $virus ) {
 666                         return new WikiErrorMsg( 'uploadvirus', htmlspecialchars($virus) );
 667                 }
 668
 669                 wfDebug( "$fname: all clear; passing.\n" );
 670                 return true;
 671         }
 672
 673         /**
 674          * Checks if the mime type of the uploaded file matches the file extension.
 675          *
 676          * @param string $mime the mime type of the uploaded file
 677          * @param string $extension The filename extension that the file is to be served with
 678          * @return bool
 679          */
 680         function verifyExtension( $mime, $extension ) {
 681                 $fname = 'SpecialUpload::verifyExtension';
 682
 683                 if (!$mime || $mime=="unknown" || $mime=="unknown/unknown") {
 684                         wfDebug( "$fname: passing file with unknown mime type\n" );
 685                         return true;
 686                 }
 687
 688                 $magic=& wfGetMimeMagic();
 689
 690                 $match= $magic->isMatchingExtension($extension,$mime);
 691
 692                 if ($match===NULL) {
 693                         wfDebug( "$fname: no file extension known for mime type $mime, passing file\n" );
 694                         return true;
 695                 } elseif ($match===true) {
 696                         wfDebug( "$fname: mime type $mime matches extension $extension, passing file\n" );
 697
 698                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 699                         return true;
 700
 701                 } else {
 702                         wfDebug( "$fname: mime type $mime mismatches file extension $extension, rejecting file\n" );
 703                         return false;
 704                 }
 705         }
 706
 707         /** Heuristig for detecting files that *could* contain JavaScript instructions or
 708         * things that may look like HTML to a browser and are thus
 709         * potentially harmful. The present implementation will produce false positives in some situations.
 710         *
 711         * @param string $file Pathname to the temporary upload file
 712         * @param string $mime The mime type of the file
 713         * @return bool true if the file contains something looking like embedded scripts
 714         */
 715         function detectScript($file,$mime) {
 716
 717                 #ugly hack: for text files, always look at the entire file.
 718                 #For binarie field, just check the first K.
 719
 720                 if (strpos($mime,'text/')===0) $chunk = file_get_contents( $file );
 721                 else {
 722                         $fp = fopen( $file, 'rb' );
 723                         $chunk = fread( $fp, 1024 );
 724                         fclose( $fp );
 725                 }
 726
 727                 $chunk= strtolower( $chunk );
 728
 729                 if (!$chunk) return false;
 730
 731                 #decode from UTF-16 if needed (could be used for obfuscation).
 732                 if (substr($chunk,0,2)=="\xfe\xff") $enc= "UTF-16BE";
 733                 elseif (substr($chunk,0,2)=="\xff\xfe") $enc= "UTF-16LE";
 734                 else $enc= NULL;
 735
 736                 if ($enc) $chunk= iconv($enc,"ASCII//IGNORE",$chunk);
 737
 738                 $chunk= trim($chunk);
 739
 740                 #FIXME: convert from UTF-16 if necessarry!
 741
 742                 wfDebug("SpecialUpload::detectScript: checking for embedded scripts and HTML stuff\n");
 743
 744                 #check for HTML doctype
 745                 if (eregi("<!DOCTYPE *X?HTML",$chunk)) return true;
 746
 747                 /**
 748                 * Internet Explorer for Windows performs some really stupid file type
 749                 * autodetection which can cause it to interpret valid image files as HTML
 750                 * and potentially execute JavaScript, creating a cross-site scripting
 751                 * attack vectors.
 752                 *
 753                 * Apple's Safari browser also performs some unsafe file type autodetection
 754                 * which can cause legitimate files to be interpreted as HTML if the
 755                 * web server is not correctly configured to send the right content-type
 756                 * (or if you're really uploading plain text and octet streams!)
 757                 *
 758                 * Returns true if IE is likely to mistake the given file for HTML.
 759                 * Also returns true if Safari would mistake the given file for HTML
 760                 * when served with a generic content-type.
 761                 */
 762
 763                 $tags = array(
 764                         '<body',
 765                         '<head',
 766                         '<html',   #also in safari
 767                         '<img',
 768                         '<pre',
 769                         '<script', #also in safari
 770                         '<table',
 771                         '<title'   #also in safari
 772                         );
 773
 774                 foreach( $tags as $tag ) {
 775                         if( false !== strpos( $chunk, $tag ) ) {
 776                                 return true;
 777                         }
 778                 }
 779
 780                 /*
 781                 * look for javascript
 782                 */
 783
 784                 #resolve entity-refs to look at attributes. may be harsh on big files... cache result?
 785                 $chunk = Sanitizer::decodeCharReferences( $chunk );
 786
 787                 #look for script-types
 788                 if (preg_match("!type\s*=\s*['\"]?\s*(\w*/)?(ecma|java)!sim",$chunk)) return true;
 789
 790                 #look for html-style script-urls
 791                 if (preg_match("!(href|src|data)\s*=\s*['\"]?\s*(ecma|java)script:!sim",$chunk)) return true;
 792
 793                 #look for css-style script-urls
 794                 if (preg_match("!url\s*\(\s*['\"]?\s*(ecma|java)script:!sim",$chunk)) return true;
 795
 796                 wfDebug("SpecialUpload::detectScript: no scripts found\n");
 797                 return false;
 798         }
 799
 800         /** Generic wrapper function for a virus scanner program.
 801         * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
 802         * $wgAntivirusRequired may be used to deny upload if the scan fails.
 803         *
 804         * @param string $file Pathname to the temporary upload file
 805         * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
 806         *         or a string containing feedback from the virus scanner if a virus was found.
 807         *         If textual feedback is missing but a virus was found, this function returns true.
 808         */
 809         function detectVirus($file) {
 810                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired;
 811
 812                 $fname= "SpecialUpload::detectVirus";
 813
 814                 if (!$wgAntivirus) { #disabled?
 815                         wfDebug("$fname: virus scanner disabled\n");
 816
 817                         return NULL;
 818                 }
 819
 820                 if (!$wgAntivirusSetup[$wgAntivirus]) {
 821                         wfDebug("$fname: unknown virus scanner: $wgAntivirus\n");
 822
 823                         $wgOut->addHTML( "<div class='error'>Bad configuration: unknown virus scanner: <i>$wgAntivirus</i></div>\n" ); #LOCALIZE
 824
 825                         return "unknown antivirus: $wgAntivirus";
 826                 }
 827
 828                 #look up scanner configuration
 829                 $virus_scanner= $wgAntivirusSetup[$wgAntivirus]["command"]; #command pattern
 830                 $virus_scanner_codes= $wgAntivirusSetup[$wgAntivirus]["codemap"]; #exit-code map
 831                 $msg_pattern= $wgAntivirusSetup[$wgAntivirus]["messagepattern"]; #message pattern
 832
 833                 $scanner= $virus_scanner; #copy, so we can resolve the pattern
 834
 835                 if (strpos($scanner,"%f")===false) $scanner.= " ".wfEscapeShellArg($file); #simple pattern: append file to scan
 836                 else $scanner= str_replace("%f",wfEscapeShellArg($file),$scanner); #complex pattern: replace "%f" with file to scan
 837
 838                 wfDebug("$fname: running virus scan: $scanner \n");
 839
 840                 #execute virus scanner
 841                 $code= false;
 842
 843                 #NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
 844                 #      that does not seem to be worth the pain.
 845                 #      Ask me (Duesentrieb) about it if it's ever needed.
 846                 if (wfIsWindows()) exec("$scanner",$output,$code);
 847                 else exec("$scanner 2>&1",$output,$code);
 848
 849                 $exit_code= $code; #remeber for user feedback
 850
 851                 if ($virus_scanner_codes) { #map exit code to AV_xxx constants.
 852                         if (isset($virus_scanner_codes[$code])) $code= $virus_scanner_codes[$code]; #explicite mapping
 853                         else if (isset($virus_scanner_codes["*"])) $code= $virus_scanner_codes["*"]; #fallback mapping
 854                 }
 855
 856                 if ($code===AV_SCAN_FAILED) { #scan failed (code was mapped to false by $virus_scanner_codes)
 857                         wfDebug("$fname: failed to scan $file (code $exit_code).\n");
 858
 859                         if ($wgAntivirusRequired) return "scan failed (code $exit_code)";
 860                         else return NULL;
 861                 }
 862                 else if ($code===AV_SCAN_ABORTED) { #scan failed because filetype is unknown (probably imune)
 863                         wfDebug("$fname: unsupported file type $file (code $exit_code).\n");
 864                         return NULL;
 865                 }
 866                 else if ($code===AV_NO_VIRUS) {
 867                         wfDebug("$fname: file passed virus scan.\n");
 868                         return false; #no virus found
 869                 }
 870                 else {
 871                         $output= join("\n",$output);
 872                         $output= trim($output);
 873
 874                         if (!$output) $output= true; #if ther's no output, return true
 875                         else if ($msg_pattern) {
 876                                 $groups= array();
 877                                 if (preg_match($msg_pattern,$output,$groups)) {
 878                                         if ($groups[1]) $output= $groups[1];
 879                                 }
 880                         }
 881
 882                         wfDebug("$fname: FOUND VIRUS! scanner feedback: $output");
 883                         return $output;
 884                 }
 885         }
 886
 887         /**
 888          * Check if the temporary file is MacBinary-encoded, as some uploads
 889          * from Internet Explorer on Mac OS Classic and Mac OS X will be.
 890          * If so, the data fork will be extracted to a second temporary file,
 891          * which will then be checked for validity and either kept or discarded.
 892          *
 893          * @access private
 894          */
 895         function checkMacBinary() {
 896                 $macbin = new MacBinary( $this->mUploadTempName );
 897                 if( $macbin->isValid() ) {
 898                         $dataFile = tempnam( wfTempDir(), "WikiMacBinary" );
 899                         $dataHandle = fopen( $dataFile, 'wb' );
 900
 901                         wfDebug( "SpecialUpload::checkMacBinary: Extracting MacBinary data fork to $dataFile\n" );
 902                         $macbin->extractData( $dataHandle );
 903
 904                         $this->mUploadTempName = $dataFile;
 905                         $this->mUploadSize = $macbin->dataForkLength();
 906
 907                         // We'll have to manually remove the new file if it's not kept.
 908                         $this->mRemoveTempFile = true;
 909                 }
 910                 $macbin->close();
 911         }
 912
 913         /**
 914          * If we've modified the upload file we need to manually remove it
 915          * on exit to clean up.
 916          * @access private
 917          */
 918         function cleanupTempFile() {
 919                 if( $this->mRemoveTempFile && file_exists( $this->mUploadTempName ) ) {
 920                         wfDebug( "SpecialUpload::cleanupTempFile: Removing temporary file $this->mUploadTempName\n" );
 921                         unlink( $this->mUploadTempName );
 922                 }
 923         }
 924
 925 }
 926 ?>