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, $mUploadError;
  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->mUploadError      = 0/*UPLOAD_ERR_OK*/;
  75                         $this->mStashed          = true;
  76                         $this->mRemoveTempFile   = false;
  77                 } else {
  78                         /**
  79                          *Check for a newly uploaded file.
  80                          */
  81                         $this->mUploadTempName = $request->getFileTempName( 'wpUploadFile' );
  82                         $this->mUploadSize     = $request->getFileSize( 'wpUploadFile' );
  83                         $this->mOname          = $request->getFileName( 'wpUploadFile' );
  84                         $this->mUploadError    = $request->getUploadError( 'wpUploadFile' );
  85                         $this->mSessionKey     = false;
  86                         $this->mStashed        = false;
  87                         $this->mRemoveTempFile = false; // PHP will handle this
  88                 }
  89         }
  90
  91         /**
  92          * Start doing stuff
  93          * @access public
  94          */
  95         function execute() {
  96                 global $wgUser, $wgOut;
  97                 global $wgEnableUploads, $wgUploadDirectory;
  98
  99                 /** Show an error message if file upload is disabled */
 100                 if( ! $wgEnableUploads ) {
 101                         $wgOut->addWikiText( wfMsg( 'uploaddisabled' ) );
 102                         return;
 103                 }
 104
 105                 /** Various rights checks */
 106                 if( !$wgUser->isAllowed( 'upload' ) || $wgUser->isBlocked() ) {
 107                         $wgOut->errorpage( 'uploadnologin', 'uploadnologintext' );
 108                         return;
 109                 }
 110                 if( wfReadOnly() ) {
 111                         $wgOut->readOnlyPage();
 112                         return;
 113                 }
 114
 115                 /** Check if the image directory is writeable, this is a common mistake */
 116                 if ( !is_writeable( $wgUploadDirectory ) ) {
 117                         $wgOut->addWikiText( wfMsg( 'upload_directory_read_only', $wgUploadDirectory ) );
 118                         return;
 119                 }
 120
 121                 if( $this->mReUpload ) {
 122                         $this->unsaveUploadedFile();
 123                         $this->mainUploadForm();
 124                 } else if ( 'submit' == $this->mAction || $this->mUpload ) {
 125                         $this->processUpload();
 126                 } else {
 127                         $this->mainUploadForm();
 128                 }
 129
 130                 $this->cleanupTempFile();
 131         }
 132
 133         /* -------------------------------------------------------------- */
 134
 135         /**
 136          * Really do the upload
 137          * Checks are made in SpecialUpload::execute()
 138          * @access private
 139          */
 140         function processUpload() {
 141                 global $wgUser, $wgOut, $wgLang, $wgContLang;
 142                 global $wgUploadDirectory;
 143                 global $wgUseCopyrightUpload, $wgCheckCopyrightUpload;
 144
 145                 /* Check for PHP error if any, requires php 4.2 or newer */
 146                 if ( $this->mUploadError == 1/*UPLOAD_ERR_INI_SIZE*/ ) {
 147                         $this->mainUploadForm( wfMsgHtml( 'largefileserver' ) );
 148                         return;
 149                 }
 150
 151                 /**
 152                  * If there was no filename or a zero size given, give up quick.
 153                  */
 154                 if( trim( $this->mOname ) == '' || empty( $this->mUploadSize ) ) {
 155                         $this->mainUploadForm( wfMsgHtml( 'emptyfile' ) );
 156                         return;
 157                 }
 158
 159                 # Chop off any directories in the given filename
 160                 if ( $this->mDestFile ) {
 161                         $basename = basename( $this->mDestFile );
 162                 } else {
 163                         $basename = basename( $this->mOname );
 164                 }
 165
 166                 /**
 167                  * We'll want to blacklist against *any* 'extension', and use
 168                  * only the final one for the whitelist.
 169                  */
 170                 list( $partname, $ext ) = $this->splitExtensions( $basename );
 171                 if( count( $ext ) ) {
 172                         $finalExt = $ext[count( $ext ) - 1];
 173                 } else {
 174                         $finalExt = '';
 175                 }
 176                 $fullExt = implode( '.', $ext );
 177
 178                 if ( strlen( $partname ) < 3 ) {
 179                         $this->mainUploadForm( wfMsgHtml( 'minlength' ) );
 180                         return;
 181                 }
 182
 183                 /**
 184                  * Filter out illegal characters, and try to make a legible name
 185                  * out of it. We'll strip some silently that Title would die on.
 186                  */
 187                 $filtered = preg_replace ( "/[^".Title::legalChars()."]|:/", '-', $basename );
 188                 $nt = Title::newFromText( $filtered );
 189                 if( is_null( $nt ) ) {
 190                         $this->uploadError( wfMsgWikiHtml( 'illegalfilename', htmlspecialchars( $filtered ) ) );
 191                         return;
 192                 }
 193                 $nt =& Title::makeTitle( NS_IMAGE, $nt->getDBkey() );
 194                 $this->mUploadSaveName = $nt->getDBkey();
 195
 196                 /**
 197                  * If the image is protected, non-sysop users won't be able
 198                  * to modify it by uploading a new revision.
 199                  */
 200                 if( !$nt->userCanEdit() ) {
 201                         return $this->uploadError( wfMsgWikiHtml( 'protectedpage' ) );
 202                 }
 203
 204                 /* Don't allow users to override the blacklist (check file extension) */
 205                 global $wgStrictFileExtensions;
 206                 global $wgFileExtensions, $wgFileBlacklist;
 207                 if( $this->checkFileExtensionList( $ext, $wgFileBlacklist ) ||
 208                         ($wgStrictFileExtensions &&
 209                                 !$this->checkFileExtension( $finalExt, $wgFileExtensions ) ) ) {
 210                         return $this->uploadError( wfMsgHtml( 'badfiletype', htmlspecialchars( $fullExt ) ) );
 211                 }
 212
 213                 /**
 214                  * Look at the contents of the file; if we can recognize the
 215                  * type but it's corrupt or data of the wrong type, we should
 216                  * probably not accept it.
 217                  */
 218                 if( !$this->mStashed ) {
 219                         $this->checkMacBinary();
 220                         $veri = $this->verify( $this->mUploadTempName, $finalExt );
 221
 222                         if( $veri !== true ) { //it's a wiki error...
 223                                 return $this->uploadError( $veri->toString() );
 224                         }
 225                 }
 226
 227                 /**
 228                  * Check for non-fatal conditions
 229                  */
 230                 if ( ! $this->mIgnoreWarning ) {
 231                         $warning = '';
 232                         if( $this->mUploadSaveName != ucfirst( $filtered ) ) {
 233                                 $warning .=  '<li>'.wfMsgHtml( 'badfilename', htmlspecialchars( $this->mUploadSaveName ) ).'</li>';
 234                         }
 235
 236                         global $wgCheckFileExtensions;
 237                         if ( $wgCheckFileExtensions ) {
 238                                 if ( ! $this->checkFileExtension( $finalExt, $wgFileExtensions ) ) {
 239                                         $warning .= '<li>'.wfMsgHtml( 'badfiletype', htmlspecialchars( $fullExt ) ).'</li>';
 240                                 }
 241                         }
 242
 243                         global $wgUploadSizeWarning;
 244                         if ( $wgUploadSizeWarning && ( $this->mUploadSize > $wgUploadSizeWarning ) ) {
 245                                 # TODO: Format $wgUploadSizeWarning to something that looks better than the raw byte
 246                                 # value, perhaps add GB,MB and KB suffixes?
 247                                 $warning .= '<li>'.wfMsgHtml( 'largefile', $wgUploadSizeWarning, $this->mUploadSize ).'</li>';
 248                         }
 249                         if ( $this->mUploadSize == 0 ) {
 250                                 $warning .= '<li>'.wfMsgHtml( 'emptyfile' ).'</li>';
 251                         }
 252
 253                         if( $nt->getArticleID() ) {
 254                                 global $wgUser;
 255                                 $sk = $wgUser->getSkin();
 256                                 $dlink = $sk->makeKnownLinkObj( $nt );
 257                                 $warning .= '<li>'.wfMsgHtml( 'fileexists', $dlink ).'</li>';
 258                         }
 259
 260                         if( $warning != '' ) {
 261                                 /**
 262                                  * Stash the file in a temporary location; the user can choose
 263                                  * to let it through and we'll complete the upload then.
 264                                  */
 265                                 return $this->uploadWarning( $warning );
 266                         }
 267                 }
 268
 269                 /**
 270                  * Try actually saving the thing...
 271                  * It will show an error form on failure.
 272                  */
 273                 $hasBeenMunged = !empty( $this->mSessionKey ) || $this->mRemoveTempFile;
 274                 if( $this->saveUploadedFile( $this->mUploadSaveName,
 275                                              $this->mUploadTempName,
 276                                              $hasBeenMunged ) ) {
 277                         /**
 278                          * Update the upload log and create the description page
 279                          * if it's a new file.
 280                          */
 281                         $img = Image::newFromName( $this->mUploadSaveName );
 282                         $success = $img->recordUpload( $this->mUploadOldVersion,
 283                                                         $this->mUploadDescription,
 284                                                         $this->mUploadCopyStatus,
 285                                                         $this->mUploadSource );
 286
 287                         if ( $success ) {
 288                                 $this->showSuccess();
 289                         } else {
 290                                 // Image::recordUpload() fails if the image went missing, which is
 291                                 // unlikely, hence the lack of a specialised message
 292                                 $wgOut->fileNotFoundError( $this->mUploadSaveName );
 293                         }
 294                 }
 295         }
 296
 297         /**
 298          * Move the uploaded file from its temporary location to the final
 299          * destination. If a previous version of the file exists, move
 300          * it into the archive subdirectory.
 301          *
 302          * @todo If the later save fails, we may have disappeared the original file.
 303          *
 304          * @param string $saveName
 305          * @param string $tempName full path to the temporary file
 306          * @param bool $useRename if true, doesn't check that the source file
 307          *                        is a PHP-managed upload temporary
 308          */
 309         function saveUploadedFile( $saveName, $tempName, $useRename = false ) {
 310                 global $wgUploadDirectory, $wgOut;
 311
 312                 $fname= "SpecialUpload::saveUploadedFile";
 313
 314                 $dest = wfImageDir( $saveName );
 315                 $archive = wfImageArchiveDir( $saveName );
 316                 $this->mSavedFile = "{$dest}/{$saveName}";
 317
 318                 if( is_file( $this->mSavedFile ) ) {
 319                         $this->mUploadOldVersion = gmdate( 'YmdHis' ) . "!{$saveName}";
 320                         wfSuppressWarnings();
 321                         $success = rename( $this->mSavedFile, "${archive}/{$this->mUploadOldVersion}" );
 322                         wfRestoreWarnings();
 323
 324                         if( ! $success ) {
 325                                 $wgOut->fileRenameError( $this->mSavedFile,
 326                                   "${archive}/{$this->mUploadOldVersion}" );
 327                                 return false;
 328                         }
 329                         else wfDebug("$fname: moved file ".$this->mSavedFile." to ${archive}/{$this->mUploadOldVersion}\n");
 330                 }
 331                 else {
 332                         $this->mUploadOldVersion = '';
 333                 }
 334
 335                 wfSuppressWarnings();
 336                 $success = $useRename
 337                         ? rename( $tempName, $this->mSavedFile )
 338                         : move_uploaded_file( $tempName, $this->mSavedFile );
 339                 wfRestoreWarnings();
 340
 341                 if( ! $success ) {
 342                         $wgOut->fileCopyError( $tempName, $this->mSavedFile );
 343                         return false;
 344                 } else {
 345                         wfDebug("$fname: wrote tempfile $tempName to ".$this->mSavedFile."\n");
 346                 }
 347
 348                 chmod( $this->mSavedFile, 0644 );
 349                 return true;
 350         }
 351
 352         /**
 353          * Stash a file in a temporary directory for later processing
 354          * after the user has confirmed it.
 355          *
 356          * If the user doesn't explicitly cancel or accept, these files
 357          * can accumulate in the temp directory.
 358          *
 359          * @param string $saveName - the destination filename
 360          * @param string $tempName - the source temporary file to save
 361          * @return string - full path the stashed file, or false on failure
 362          * @access private
 363          */
 364         function saveTempUploadedFile( $saveName, $tempName ) {
 365                 global $wgOut;
 366                 $archive = wfImageArchiveDir( $saveName, 'temp' );
 367                 $stash = $archive . '/' . gmdate( "YmdHis" ) . '!' . $saveName;
 368
 369                 $success = $this->mRemoveTempFile
 370                         ? rename( $tempName, $stash )
 371                         : move_uploaded_file( $tempName, $stash );
 372                 if ( !$success ) {
 373                         $wgOut->fileCopyError( $tempName, $stash );
 374                         return false;
 375                 }
 376
 377                 return $stash;
 378         }
 379
 380         /**
 381          * Stash a file in a temporary directory for later processing,
 382          * and save the necessary descriptive info into the session.
 383          * Returns a key value which will be passed through a form
 384          * to pick up the path info on a later invocation.
 385          *
 386          * @return int
 387          * @access private
 388          */
 389         function stashSession() {
 390                 $stash = $this->saveTempUploadedFile(
 391                         $this->mUploadSaveName, $this->mUploadTempName );
 392
 393                 if( !$stash ) {
 394                         # Couldn't save the file.
 395                         return false;
 396                 }
 397
 398                 $key = mt_rand( 0, 0x7fffffff );
 399                 $_SESSION['wsUploadData'][$key] = array(
 400                         'mUploadTempName' => $stash,
 401                         'mUploadSize'     => $this->mUploadSize,
 402                         'mOname'          => $this->mOname );
 403                 return $key;
 404         }
 405
 406         /**
 407          * Remove a temporarily kept file stashed by saveTempUploadedFile().
 408          * @access private
 409          */
 410         function unsaveUploadedFile() {
 411                 global $wgOut;
 412                 wfSuppressWarnings();
 413                 $success = unlink( $this->mUploadTempName );
 414                 wfRestoreWarnings();
 415                 if ( ! $success ) {
 416                         $wgOut->fileDeleteError( $this->mUploadTempName );
 417                 }
 418         }
 419
 420         /* -------------------------------------------------------------- */
 421
 422         /**
 423          * Show some text and linkage on successful upload.
 424          * @access private
 425          */
 426         function showSuccess() {
 427                 global $wgUser, $wgOut, $wgContLang;
 428
 429                 $sk = $wgUser->getSkin();
 430                 $ilink = $sk->makeMediaLink( $this->mUploadSaveName, Image::imageUrl( $this->mUploadSaveName ) );
 431                 $dname = $wgContLang->getNsText( NS_IMAGE ) . ':'.$this->mUploadSaveName;
 432                 $dlink = $sk->makeKnownLink( $dname, $dname );
 433
 434                 $wgOut->addHTML( '<h2>' . wfMsgHtml( 'successfulupload' ) . "</h2>\n" );
 435                 $text = wfMsgWikiHtml( 'fileuploaded', $ilink, $dlink );
 436                 $wgOut->addHTML( $text );
 437                 $wgOut->returnToMain( false );
 438         }
 439
 440         /**
 441          * @param string $error as HTML
 442          * @access private
 443          */
 444         function uploadError( $error ) {
 445                 global $wgOut;
 446                 $wgOut->addHTML( "<h2>" . wfMsgHtml( 'uploadwarning' ) . "</h2>\n" );
 447                 $wgOut->addHTML( "<span class='error'>{$error}</span>\n" );
 448         }
 449
 450         /**
 451          * There's something wrong with this file, not enough to reject it
 452          * totally but we require manual intervention to save it for real.
 453          * Stash it away, then present a form asking to confirm or cancel.
 454          *
 455          * @param string $warning as HTML
 456          * @access private
 457          */
 458         function uploadWarning( $warning ) {
 459                 global $wgOut, $wgUser, $wgLang, $wgUploadDirectory, $wgRequest;
 460                 global $wgUseCopyrightUpload;
 461
 462                 $this->mSessionKey = $this->stashSession();
 463                 if( !$this->mSessionKey ) {
 464                         # Couldn't save file; an error has been displayed so let's go.
 465                         return;
 466                 }
 467
 468                 $wgOut->addHTML( "<h2>" . wfMsgHtml( 'uploadwarning' ) . "</h2>\n" );
 469                 $wgOut->addHTML( "<ul class='warning'>{$warning}</ul><br />\n" );
 470
 471                 $save = wfMsgHtml( 'savefile' );
 472                 $reupload = wfMsgHtml( 'reupload' );
 473                 $iw = wfMsgWikiHtml( 'ignorewarning' );
 474                 $reup = wfMsgWikiHtml( 'reuploaddesc' );
 475                 $titleObj = Title::makeTitle( NS_SPECIAL, 'Upload' );
 476                 $action = $titleObj->escapeLocalURL( 'action=submit' );
 477
 478                 if ( $wgUseCopyrightUpload )
 479                 {
 480                         $copyright =  "
 481         <input type='hidden' name='wpUploadCopyStatus' value=\"" . htmlspecialchars( $this->mUploadCopyStatus ) . "\" />
 482         <input type='hidden' name='wpUploadSource' value=\"" . htmlspecialchars( $this->mUploadSource ) . "\" />
 483         ";
 484                 } else {
 485                         $copyright = "";
 486                 }
 487
 488                 $wgOut->addHTML( "
 489         <form id='uploadwarning' method='post' enctype='multipart/form-data' action='$action'>
 490                 <input type='hidden' name='wpIgnoreWarning' value='1' />
 491                 <input type='hidden' name='wpSessionKey' value=\"" . htmlspecialchars( $this->mSessionKey ) . "\" />
 492                 <input type='hidden' name='wpUploadDescription' value=\"" . htmlspecialchars( $this->mUploadDescription ) . "\" />
 493                 <input type='hidden' name='wpDestFile' value=\"" . htmlspecialchars( $this->mDestFile ) . "\" />
 494         {$copyright}
 495         <table border='0'>
 496                 <tr>
 497                         <tr>
 498                                 <td align='right'>
 499                                         <input tabindex='2' type='submit' name='wpUpload' value='$save' />
 500                                 </td>
 501                                 <td align='left'>$iw</td>
 502                         </tr>
 503                         <tr>
 504                                 <td align='right'>
 505                                         <input tabindex='2' type='submit' name='wpReUpload' value='{$reupload}' />
 506                                 </td>
 507                                 <td align='left'>$reup</td>
 508                         </tr>
 509                 </tr>
 510         </table></form>\n" );
 511         }
 512
 513         /**
 514          * Displays the main upload form, optionally with a highlighted
 515          * error message up at the top.
 516          *
 517          * @param string $msg as HTML
 518          * @access private
 519          */
 520         function mainUploadForm( $msg='' ) {
 521                 global $wgOut, $wgUser, $wgLang, $wgUploadDirectory, $wgRequest;
 522                 global $wgUseCopyrightUpload;
 523
 524                 $cols = intval($wgUser->getOption( 'cols' ));
 525                 $ew = $wgUser->getOption( 'editwidth' );
 526                 if ( $ew ) $ew = " style=\"width:100%\"";
 527                 else $ew = '';
 528
 529                 if ( '' != $msg ) {
 530                         $sub = wfMsgHtml( 'uploaderror' );
 531                         $wgOut->addHTML( "<h2>{$sub}</h2>\n" .
 532                           "<span class='error'>{$msg}</span>\n" );
 533                 }
 534                 $wgOut->addWikiText( wfMsg( 'uploadtext' ) );
 535                 $sk = $wgUser->getSkin();
 536
 537
 538                 $sourcefilename = wfMsgHtml( 'sourcefilename' );
 539                 $destfilename = wfMsgHtml( 'destfilename' );
 540                 $summary = wfMsgWikiHtml( 'fileuploadsummary' );
 541                 $ulb = wfMsgHtml( 'uploadbtn' );
 542
 543
 544                 $titleObj = Title::makeTitle( NS_SPECIAL, 'Upload' );
 545                 $action = $titleObj->escapeLocalURL();
 546
 547                 $encDestFile = htmlspecialchars( $this->mDestFile );
 548                 $source = null;
 549
 550                 if ( $wgUseCopyrightUpload )
 551                   {
 552                         $source = "
 553         <td align='right' nowrap='nowrap'>" . wfMsg ( 'filestatus' ) . ":</td>
 554         <td><input tabindex='3' type='text' name=\"wpUploadCopyStatus\" value=\"" .
 555         htmlspecialchars($this->mUploadCopyStatus). "\" size='40' /></td>
 556         </tr><tr>
 557         <td align='right'>". wfMsg ( 'filesource' ) . ":</td>
 558         <td><input tabindex='4' type='text' name='wpUploadSource' value=\"" .
 559         htmlspecialchars($this->mUploadSource). "\" size='40' /></td>
 560         " ;
 561                   }
 562
 563                 $wgOut->addHTML( "
 564         <form id='upload' method='post' enctype='multipart/form-data' action=\"$action\">
 565         <table border='0'><tr>
 566
 567         <td align='right'>{$sourcefilename}:</td><td align='left'>
 568         <input tabindex='1' type='file' name='wpUploadFile' id='wpUploadFile' onchange='fillDestFilename()' size='40' />
 569         </td></tr><tr>
 570
 571         <td align='right'>{$destfilename}:</td><td align='left'>
 572         <input tabindex='1' type='text' name='wpDestFile' id='wpDestFile' size='40' value=\"$encDestFile\" />
 573         </td></tr><tr>
 574
 575         <td align='right'>{$summary}</td><td align='left'>
 576         <textarea tabindex='2' name='wpUploadDescription' rows='6' cols='{$cols}'{$ew}>"
 577           . htmlspecialchars( $this->mUploadDescription ) .
 578         "</textarea>
 579         </td></tr><tr>
 580         {$source}
 581         </tr>
 582         <tr><td></td><td align='left'>
 583         <input tabindex='5' type='submit' name='wpUpload' value=\"{$ulb}\" />
 584         </td></tr></table></form>\n" );
 585         }
 586
 587         /* -------------------------------------------------------------- */
 588
 589         /**
 590          * Split a file into a base name and all dot-delimited 'extensions'
 591          * on the end. Some web server configurations will fall back to
 592          * earlier pseudo-'extensions' to determine type and execute
 593          * scripts, so the blacklist needs to check them all.
 594          *
 595          * @return array
 596          */
 597         function splitExtensions( $filename ) {
 598                 $bits = explode( '.', $filename );
 599                 $basename = array_shift( $bits );
 600                 return array( $basename, $bits );
 601         }
 602
 603         /**
 604          * Perform case-insensitive match against a list of file extensions.
 605          * Returns true if the extension is in the list.
 606          *
 607          * @param string $ext
 608          * @param array $list
 609          * @return bool
 610          */
 611         function checkFileExtension( $ext, $list ) {
 612                 return in_array( strtolower( $ext ), $list );
 613         }
 614
 615         /**
 616          * Perform case-insensitive match against a list of file extensions.
 617          * Returns true if any of the extensions are in the list.
 618          *
 619          * @param array $ext
 620          * @param array $list
 621          * @return bool
 622          */
 623         function checkFileExtensionList( $ext, $list ) {
 624                 foreach( $ext as $e ) {
 625                         if( in_array( strtolower( $e ), $list ) ) {
 626                                 return true;
 627                         }
 628                 }
 629                 return false;
 630         }
 631
 632         /**
 633          * Verifies that it's ok to include the uploaded file
 634          *
 635          * @param string $tmpfile the full path of the temporary file to verify
 636          * @param string $extension The filename extension that the file is to be served with
 637          * @return mixed true of the file is verified, a WikiError object otherwise.
 638          */
 639         function verify( $tmpfile, $extension ) {
 640                 #magically determine mime type
 641                 $magic=& wfGetMimeMagic();
 642                 $mime= $magic->guessMimeType($tmpfile,false);
 643
 644                 $fname= "SpecialUpload::verify";
 645
 646                 #check mime type, if desired
 647                 global $wgVerifyMimeType;
 648                 if ($wgVerifyMimeType) {
 649
 650                         #check mime type against file extension
 651                         if( !$this->verifyExtension( $mime, $extension ) ) {
 652                                 return new WikiErrorMsg( 'uploadcorrupt' );
 653                         }
 654
 655                         #check mime type blacklist
 656                         global $wgMimeTypeBlacklist;
 657                         if( isset($wgMimeTypeBlacklist) && !is_null($wgMimeTypeBlacklist)
 658                                 && $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 659                                 return new WikiErrorMsg( 'badfiletype', htmlspecialchars( $mime ) );
 660                         }
 661                 }
 662
 663                 #check for htmlish code and javascript
 664                 if( $this->detectScript ( $tmpfile, $mime ) ) {
 665                         return new WikiErrorMsg( 'uploadscripted' );
 666                 }
 667
 668                 /**
 669                 * Scan the uploaded file for viruses
 670                 */
 671                 $virus= $this->detectVirus($tmpfile);
 672                 if ( $virus ) {
 673                         return new WikiErrorMsg( 'uploadvirus', htmlspecialchars($virus) );
 674                 }
 675
 676                 wfDebug( "$fname: all clear; passing.\n" );
 677                 return true;
 678         }
 679
 680         /**
 681          * Checks if the mime type of the uploaded file matches the file extension.
 682          *
 683          * @param string $mime the mime type of the uploaded file
 684          * @param string $extension The filename extension that the file is to be served with
 685          * @return bool
 686          */
 687         function verifyExtension( $mime, $extension ) {
 688                 $fname = 'SpecialUpload::verifyExtension';
 689
 690                 if (!$mime || $mime=="unknown" || $mime=="unknown/unknown") {
 691                         wfDebug( "$fname: passing file with unknown mime type\n" );
 692                         return true;
 693                 }
 694
 695                 $magic=& wfGetMimeMagic();
 696
 697                 $match= $magic->isMatchingExtension($extension,$mime);
 698
 699                 if ($match===NULL) {
 700                         wfDebug( "$fname: no file extension known for mime type $mime, passing file\n" );
 701                         return true;
 702                 } elseif ($match===true) {
 703                         wfDebug( "$fname: mime type $mime matches extension $extension, passing file\n" );
 704
 705                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 706                         return true;
 707
 708                 } else {
 709                         wfDebug( "$fname: mime type $mime mismatches file extension $extension, rejecting file\n" );
 710                         return false;
 711                 }
 712         }
 713
 714         /** Heuristig for detecting files that *could* contain JavaScript instructions or
 715         * things that may look like HTML to a browser and are thus
 716         * potentially harmful. The present implementation will produce false positives in some situations.
 717         *
 718         * @param string $file Pathname to the temporary upload file
 719         * @param string $mime The mime type of the file
 720         * @return bool true if the file contains something looking like embedded scripts
 721         */
 722         function detectScript($file,$mime) {
 723
 724                 #ugly hack: for text files, always look at the entire file.
 725                 #For binarie field, just check the first K.
 726
 727                 if (strpos($mime,'text/')===0) $chunk = file_get_contents( $file );
 728                 else {
 729                         $fp = fopen( $file, 'rb' );
 730                         $chunk = fread( $fp, 1024 );
 731                         fclose( $fp );
 732                 }
 733
 734                 $chunk= strtolower( $chunk );
 735
 736                 if (!$chunk) return false;
 737
 738                 #decode from UTF-16 if needed (could be used for obfuscation).
 739                 if (substr($chunk,0,2)=="\xfe\xff") $enc= "UTF-16BE";
 740                 elseif (substr($chunk,0,2)=="\xff\xfe") $enc= "UTF-16LE";
 741                 else $enc= NULL;
 742
 743                 if ($enc) $chunk= iconv($enc,"ASCII//IGNORE",$chunk);
 744
 745                 $chunk= trim($chunk);
 746
 747                 #FIXME: convert from UTF-16 if necessarry!
 748
 749                 wfDebug("SpecialUpload::detectScript: checking for embedded scripts and HTML stuff\n");
 750
 751                 #check for HTML doctype
 752                 if (eregi("<!DOCTYPE *X?HTML",$chunk)) return true;
 753
 754                 /**
 755                 * Internet Explorer for Windows performs some really stupid file type
 756                 * autodetection which can cause it to interpret valid image files as HTML
 757                 * and potentially execute JavaScript, creating a cross-site scripting
 758                 * attack vectors.
 759                 *
 760                 * Apple's Safari browser also performs some unsafe file type autodetection
 761                 * which can cause legitimate files to be interpreted as HTML if the
 762                 * web server is not correctly configured to send the right content-type
 763                 * (or if you're really uploading plain text and octet streams!)
 764                 *
 765                 * Returns true if IE is likely to mistake the given file for HTML.
 766                 * Also returns true if Safari would mistake the given file for HTML
 767                 * when served with a generic content-type.
 768                 */
 769
 770                 $tags = array(
 771                         '<body',
 772                         '<head',
 773                         '<html',   #also in safari
 774                         '<img',
 775                         '<pre',
 776                         '<script', #also in safari
 777                         '<table',
 778                         '<title'   #also in safari
 779                         );
 780
 781                 foreach( $tags as $tag ) {
 782                         if( false !== strpos( $chunk, $tag ) ) {
 783                                 return true;
 784                         }
 785                 }
 786
 787                 /*
 788                 * look for javascript
 789                 */
 790
 791                 #resolve entity-refs to look at attributes. may be harsh on big files... cache result?
 792                 $chunk = Sanitizer::decodeCharReferences( $chunk );
 793
 794                 #look for script-types
 795                 if (preg_match("!type\s*=\s*['\"]?\s*(\w*/)?(ecma|java)!sim",$chunk)) return true;
 796
 797                 #look for html-style script-urls
 798                 if (preg_match("!(href|src|data)\s*=\s*['\"]?\s*(ecma|java)script:!sim",$chunk)) return true;
 799
 800                 #look for css-style script-urls
 801                 if (preg_match("!url\s*\(\s*['\"]?\s*(ecma|java)script:!sim",$chunk)) return true;
 802
 803                 wfDebug("SpecialUpload::detectScript: no scripts found\n");
 804                 return false;
 805         }
 806
 807         /** Generic wrapper function for a virus scanner program.
 808         * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
 809         * $wgAntivirusRequired may be used to deny upload if the scan fails.
 810         *
 811         * @param string $file Pathname to the temporary upload file
 812         * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
 813         *         or a string containing feedback from the virus scanner if a virus was found.
 814         *         If textual feedback is missing but a virus was found, this function returns true.
 815         */
 816         function detectVirus($file) {
 817                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired;
 818
 819                 $fname= "SpecialUpload::detectVirus";
 820
 821                 if (!$wgAntivirus) { #disabled?
 822                         wfDebug("$fname: virus scanner disabled\n");
 823
 824                         return NULL;
 825                 }
 826
 827                 if (!$wgAntivirusSetup[$wgAntivirus]) {
 828                         wfDebug("$fname: unknown virus scanner: $wgAntivirus\n");
 829
 830                         $wgOut->addHTML( "<div class='error'>Bad configuration: unknown virus scanner: <i>$wgAntivirus</i></div>\n" ); #LOCALIZE
 831
 832                         return "unknown antivirus: $wgAntivirus";
 833                 }
 834
 835                 #look up scanner configuration
 836                 $virus_scanner= $wgAntivirusSetup[$wgAntivirus]["command"]; #command pattern
 837                 $virus_scanner_codes= $wgAntivirusSetup[$wgAntivirus]["codemap"]; #exit-code map
 838                 $msg_pattern= $wgAntivirusSetup[$wgAntivirus]["messagepattern"]; #message pattern
 839
 840                 $scanner= $virus_scanner; #copy, so we can resolve the pattern
 841
 842                 if (strpos($scanner,"%f")===false) $scanner.= " ".wfEscapeShellArg($file); #simple pattern: append file to scan
 843                 else $scanner= str_replace("%f",wfEscapeShellArg($file),$scanner); #complex pattern: replace "%f" with file to scan
 844
 845                 wfDebug("$fname: running virus scan: $scanner \n");
 846
 847                 #execute virus scanner
 848                 $code= false;
 849
 850                 #NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
 851                 #      that does not seem to be worth the pain.
 852                 #      Ask me (Duesentrieb) about it if it's ever needed.
 853                 if (wfIsWindows()) exec("$scanner",$output,$code);
 854                 else exec("$scanner 2>&1",$output,$code);
 855
 856                 $exit_code= $code; #remeber for user feedback
 857
 858                 if ($virus_scanner_codes) { #map exit code to AV_xxx constants.
 859                         if (isset($virus_scanner_codes[$code])) $code= $virus_scanner_codes[$code]; #explicite mapping
 860                         else if (isset($virus_scanner_codes["*"])) $code= $virus_scanner_codes["*"]; #fallback mapping
 861                 }
 862
 863                 if ($code===AV_SCAN_FAILED) { #scan failed (code was mapped to false by $virus_scanner_codes)
 864                         wfDebug("$fname: failed to scan $file (code $exit_code).\n");
 865
 866                         if ($wgAntivirusRequired) return "scan failed (code $exit_code)";
 867                         else return NULL;
 868                 }
 869                 else if ($code===AV_SCAN_ABORTED) { #scan failed because filetype is unknown (probably imune)
 870                         wfDebug("$fname: unsupported file type $file (code $exit_code).\n");
 871                         return NULL;
 872                 }
 873                 else if ($code===AV_NO_VIRUS) {
 874                         wfDebug("$fname: file passed virus scan.\n");
 875                         return false; #no virus found
 876                 }
 877                 else {
 878                         $output= join("\n",$output);
 879                         $output= trim($output);
 880
 881                         if (!$output) $output= true; #if ther's no output, return true
 882                         else if ($msg_pattern) {
 883                                 $groups= array();
 884                                 if (preg_match($msg_pattern,$output,$groups)) {
 885                                         if ($groups[1]) $output= $groups[1];
 886                                 }
 887                         }
 888
 889                         wfDebug("$fname: FOUND VIRUS! scanner feedback: $output");
 890                         return $output;
 891                 }
 892         }
 893
 894         /**
 895          * Check if the temporary file is MacBinary-encoded, as some uploads
 896          * from Internet Explorer on Mac OS Classic and Mac OS X will be.
 897          * If so, the data fork will be extracted to a second temporary file,
 898          * which will then be checked for validity and either kept or discarded.
 899          *
 900          * @access private
 901          */
 902         function checkMacBinary() {
 903                 $macbin = new MacBinary( $this->mUploadTempName );
 904                 if( $macbin->isValid() ) {
 905                         $dataFile = tempnam( wfTempDir(), "WikiMacBinary" );
 906                         $dataHandle = fopen( $dataFile, 'wb' );
 907
 908                         wfDebug( "SpecialUpload::checkMacBinary: Extracting MacBinary data fork to $dataFile\n" );
 909                         $macbin->extractData( $dataHandle );
 910
 911                         $this->mUploadTempName = $dataFile;
 912                         $this->mUploadSize = $macbin->dataForkLength();
 913
 914                         // We'll have to manually remove the new file if it's not kept.
 915                         $this->mRemoveTempFile = true;
 916                 }
 917                 $macbin->close();
 918         }
 919
 920         /**
 921          * If we've modified the upload file we need to manually remove it
 922          * on exit to clean up.
 923          * @access private
 924          */
 925         function cleanupTempFile() {
 926                 if( $this->mRemoveTempFile && file_exists( $this->mUploadTempName ) ) {
 927                         wfDebug( "SpecialUpload::cleanupTempFile: Removing temporary file $this->mUploadTempName\n" );
 928                         unlink( $this->mUploadTempName );
 929                 }
 930         }
 931
 932 }
 933 ?>