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 /**
  14  * Entry point
  15  */
  16 function wfSpecialUpload() {
  17         global $wgRequest;
  18         $form = new UploadForm( $wgRequest );
  19         $form->execute();
  20 }
  21
  22 /**
  23  *
  24  * @package MediaWiki
  25  * @subpackage SpecialPage
  26  */
  27 class UploadForm {
  28         /**#@+
  29          * @access private
  30          */
  31         var $mUploadAffirm, $mUploadFile, $mUploadDescription, $mIgnoreWarning;
  32         var $mUploadSaveName, $mUploadTempName, $mUploadSize, $mUploadOldVersion;
  33         var $mUploadCopyStatus, $mUploadSource, $mReUpload, $mAction, $mUpload;
  34         var $mOname, $mSessionKey, $mStashed;
  35         /**#@-*/
  36
  37         /**
  38          * Constructor : initialise object
  39          * Get data POSTed through the form and assign them to the object
  40          * @param $request Data posted.
  41          */
  42         function UploadForm( &$request ) {
  43                 if( !$request->wasPosted() ) {
  44                         # GET requests just give the main form; no data.
  45                         return;
  46                 }
  47
  48                 $this->mUploadAffirm      = $request->getCheck( 'wpUploadAffirm' );
  49                 $this->mIgnoreWarning     = $request->getCheck( 'wpIgnoreWarning');
  50                 $this->mReUpload          = $request->getCheck( 'wpReUpload' );
  51                 $this->mUpload            = $request->getCheck( 'wpUpload' );
  52
  53                 $this->mUploadDescription = $request->getText( 'wpUploadDescription' );
  54                 $this->mUploadCopyStatus  = $request->getText( 'wpUploadCopyStatus' );
  55                 $this->mUploadSource      = $request->getText( 'wpUploadSource');
  56
  57                 $this->mAction            = $request->getVal( 'action' );
  58
  59                 $this->mSessionKey        = $request->getInt( 'wpSessionKey' );
  60                 if( !empty( $this->mSessionKey ) &&
  61                         isset( $_SESSION['wsUploadData'][$this->mSessionKey] ) ) {
  62                         /**
  63                          * Confirming a temporarily stashed upload.
  64                          * We don't want path names to be forged, so we keep
  65                          * them in the session on the server and just give
  66                          * an opaque key to the user agent.
  67                          */
  68                         $data = $_SESSION['wsUploadData'][$this->mSessionKey];
  69                         $this->mUploadTempName   = $data['mUploadTempName'];
  70                         $this->mUploadSize       = $data['mUploadSize'];
  71                         $this->mOname            = $data['mOname'];
  72                         $this->mStashed          = true;
  73                 } else {
  74                         /**
  75                          *Check for a newly uploaded file.
  76                          */
  77                         $this->mUploadTempName = $request->getFileTempName( 'wpUploadFile' );
  78                         $this->mUploadSize     = $request->getFileSize( 'wpUploadFile' );
  79                         $this->mOname          = $request->getFileName( 'wpUploadFile' );
  80                         $this->mSessionKey     = false;
  81                         $this->mStashed        = false;
  82                 }
  83         }
  84
  85         /**
  86          * Start doing stuff
  87          * @access public
  88          */
  89         function execute() {
  90                 global $wgUser, $wgOut;
  91                 global $wgEnableUploads;
  92
  93                 /** Show an error message if file upload is disabled */
  94                 if( ! $wgEnableUploads ) {
  95                         $wgOut->addWikiText( wfMsg( 'uploaddisabled' ) );
  96                         return;
  97                 }
  98
  99                 /** Various rights checks */
 100                 if( ( $wgUser->isAnon() )
 101                          OR $wgUser->isBlocked() ) {
 102                         $wgOut->errorpage( 'uploadnologin', 'uploadnologintext' );
 103                         return;
 104                 }
 105                 if( wfReadOnly() ) {
 106                         $wgOut->readOnlyPage();
 107                         return;
 108                 }
 109
 110                 if( $this->mReUpload ) {
 111                         $this->unsaveUploadedFile();
 112                         $this->mainUploadForm();
 113                 } else if ( 'submit' == $this->mAction || $this->mUpload ) {
 114                         $this->processUpload();
 115                 } else {
 116                         $this->mainUploadForm();
 117                 }
 118         }
 119
 120         /* -------------------------------------------------------------- */
 121
 122         /**
 123          * Really do the upload
 124          * Checks are made in SpecialUpload::execute()
 125          * @access private
 126          */
 127         function processUpload() {
 128                 global $wgUser, $wgOut, $wgLang, $wgContLang;
 129                 global $wgUploadDirectory;
 130                 global $wgUseCopyrightUpload, $wgCheckCopyrightUpload;
 131
 132                 /**
 133                  * If there was no filename or a zero size given, give up quick.
 134                  */
 135                 if( ( trim( $this->mOname ) == '' ) || empty( $this->mUploadSize ) ) {
 136                         return $this->mainUploadForm('<li>'.wfMsg( 'emptyfile' ).'</li>');
 137                 }
 138
 139                 /**
 140                  * When using detailed copyright, if user filled field, assume he
 141                  * confirmed the upload
 142                  */
 143                 if ( $wgUseCopyrightUpload ) {
 144                         $this->mUploadAffirm = true;
 145                         if( $wgCheckCopyrightUpload &&
 146                             ( trim( $this->mUploadCopyStatus ) == '' ||
 147                               trim( $this->mUploadSource     ) == '' ) ) {
 148                                 $this->mUploadAffirm = false;
 149                         }
 150                 }
 151
 152                 /** User need to confirm his upload */
 153                 if( !$this->mUploadAffirm ) {
 154                         $this->mainUploadForm( wfMsg( 'noaffirmation' ) );
 155                         return;
 156                 }
 157
 158                 # Chop off any directories in the given filename
 159                 $basename = basename( $this->mOname );
 160
 161                 /**
 162                  * We'll want to blacklist against *any* 'extension', and use
 163                  * only the final one for the whitelist.
 164                  */
 165                 list( $partname, $ext ) = $this->splitExtensions( $basename );
 166                 if( count( $ext ) ) {
 167                         $finalExt = $ext[count( $ext ) - 1];
 168                 } else {
 169                         $finalExt = '';
 170                 }
 171                 $fullExt = implode( '.', $ext );
 172
 173                 if ( strlen( $partname ) < 3 ) {
 174                         $this->mainUploadForm( wfMsg( 'minlength' ) );
 175                         return;
 176                 }
 177
 178                 /**
 179                  * Filter out illegal characters, and try to make a legible name
 180                  * out of it. We'll strip some silently that Title would die on.
 181                  */
 182                 $filtered = preg_replace ( "/[^".Title::legalChars()."]|:/", '-', $basename );
 183                 $nt = Title::newFromText( $filtered );
 184                 if( is_null( $nt ) ) {
 185                         return $this->uploadError( wfMsg( 'illegalfilename', htmlspecialchars( $filtered ) ) );
 186                 }
 187                 $nt =& Title::makeTitle( NS_IMAGE, $nt->getDBkey() );
 188                 $this->mUploadSaveName = $nt->getDBkey();
 189
 190                 /**
 191                  * If the image is protected, non-sysop users won't be able
 192                  * to modify it by uploading a new revision.
 193                  */
 194                 if( !$nt->userCanEdit() ) {
 195                         return $this->uploadError( wfMsg( 'protectedpage' ) );
 196                 }
 197
 198                 /* Don't allow users to override the blacklist */
 199                 global $wgStrictFileExtensions;
 200                 global $wgFileExtensions, $wgFileBlacklist;
 201                 if( $this->checkFileExtensionList( $ext, $wgFileBlacklist ) ||
 202                         ($wgStrictFileExtensions &&
 203                                 !$this->checkFileExtension( $finalExt, $wgFileExtensions ) ) ) {
 204                         return $this->uploadError( wfMsg( 'badfiletype', htmlspecialchars( $fullExt ) ) );
 205                 }
 206
 207                 /**
 208                  * Look at the contents of the file; if we can recognize the
 209                  * type but it's corrupt or data of the wrong type, we should
 210                  * probably not accept it.
 211                  */
 212                 if( !$this->mStashed && !$this->verify( $this->mUploadTempName, $finalExt ) ) {
 213                         return $this->uploadError( wfMsg( 'uploadcorrupt' ) );
 214                 }
 215
 216                 /**
 217                  * Check for non-fatal conditions
 218                  */
 219                 if ( ! $this->mIgnoreWarning ) {
 220                         $warning = '';
 221                         if( $this->mUploadSaveName != ucfirst( $filtered ) ) {
 222                                 $warning .=  '<li>'.wfMsg( 'badfilename', htmlspecialchars( $this->mUploadSaveName ) ).'</li>';
 223                         }
 224
 225                         global $wgCheckFileExtensions;
 226                         if ( $wgCheckFileExtensions ) {
 227                                 if ( ! $this->checkFileExtension( $finalExt, $wgFileExtensions ) ) {
 228                                         $warning .= '<li>'.wfMsg( 'badfiletype', htmlspecialchars( $fullExt ) ).'</li>';
 229                                 }
 230                         }
 231
 232                         global $wgUploadSizeWarning;
 233                         if ( $wgUploadSizeWarning && ( $this->mUploadSize > $wgUploadSizeWarning ) ) {
 234                                 # TODO: Format $wgUploadSizeWarning to something that looks better than the raw byte
 235                                 # value, perhaps add GB,MB and KB suffixes?
 236                                 $warning .= '<li>'.wfMsg( 'largefile', $wgUploadSizeWarning, $this->mUploadSize ).'</li>';
 237                         }
 238                         if ( $this->mUploadSize == 0 ) {
 239                                 $warning .= '<li>'.wfMsg( 'emptyfile' ).'</li>';
 240                         }
 241
 242                         if( $nt->getArticleID() ) {
 243                                 global $wgUser;
 244                                 $sk = $wgUser->getSkin();
 245                                 $dlink = $sk->makeKnownLinkObj( $nt );
 246                                 $warning .= '<li>'.wfMsg( 'fileexists', $dlink ).'</li>';
 247                         }
 248
 249                         if( $warning != '' ) {
 250                                 /**
 251                                  * Stash the file in a temporary location; the user can choose
 252                                  * to let it through and we'll complete the upload then.
 253                                  */
 254                                 return $this->uploadWarning($warning);
 255                         }
 256                 }
 257
 258                 /**
 259                  * Try actually saving the thing...
 260                  * It will show an error form on failure.
 261                  */
 262                 if( $this->saveUploadedFile( $this->mUploadSaveName,
 263                                              $this->mUploadTempName,
 264                                              !empty( $this->mSessionKey ) ) ) {
 265                         /**
 266                          * Update the upload log and create the description page
 267                          * if it's a new file.
 268                          */
 269                         wfRecordUpload( $this->mUploadSaveName,
 270                                         $this->mUploadOldVersion,
 271                                         $this->mUploadSize,
 272                                         $this->mUploadDescription,
 273                                         $this->mUploadCopyStatus,
 274                                         $this->mUploadSource );
 275
 276                         /* refresh image metadata cache */
 277                         new Image( $this->mUploadSaveName, true );
 278
 279                         $this->showSuccess();
 280                 }
 281         }
 282
 283         /**
 284          * Move the uploaded file from its temporary location to the final
 285          * destination. If a previous version of the file exists, move
 286          * it into the archive subdirectory.
 287          *
 288          * @todo If the later save fails, we may have disappeared the original file.
 289          *
 290          * @param string $saveName
 291          * @param string $tempName full path to the temporary file
 292          * @param bool $useRename if true, doesn't check that the source file
 293          *                        is a PHP-managed upload temporary
 294          */
 295         function saveUploadedFile( $saveName, $tempName, $useRename = false ) {
 296                 global $wgUploadDirectory, $wgOut;
 297
 298                 $dest = wfImageDir( $saveName );
 299                 $archive = wfImageArchiveDir( $saveName );
 300                 $this->mSavedFile = "{$dest}/{$saveName}";
 301
 302                 if( is_file( $this->mSavedFile ) ) {
 303                         $this->mUploadOldVersion = gmdate( 'YmdHis' ) . "!{$saveName}";
 304                         wfSuppressWarnings();
 305                         $success = rename( $this->mSavedFile, "${archive}/{$this->mUploadOldVersion}" );
 306                         wfRestoreWarnings();
 307
 308                         if( ! $success ) {
 309                                 $wgOut->fileRenameError( $this->mSavedFile,
 310                                   "${archive}/{$this->mUploadOldVersion}" );
 311                                 return false;
 312                         }
 313                 } else {
 314                         $this->mUploadOldVersion = '';
 315                 }
 316
 317                 if( $useRename ) {
 318                         wfSuppressWarnings();
 319                         $success = rename( $tempName, $this->mSavedFile );
 320                         wfRestoreWarnings();
 321
 322                         if( ! $success ) {
 323                                 $wgOut->fileCopyError( $tempName, $this->mSavedFile );
 324                                 return false;
 325                         }
 326                 } else {
 327                         wfSuppressWarnings();
 328                         $success = move_uploaded_file( $tempName, $this->mSavedFile );
 329                         wfRestoreWarnings();
 330
 331                         if( ! $success ) {
 332                                 $wgOut->fileCopyError( $tempName, $this->mSavedFile );
 333                                 return false;
 334                         }
 335                 }
 336                 chmod( $this->mSavedFile, 0644 );
 337                 return true;
 338         }
 339
 340         /**
 341          * Stash a file in a temporary directory for later processing
 342          * after the user has confirmed it.
 343          *
 344          * If the user doesn't explicitly cancel or accept, these files
 345          * can accumulate in the temp directory.
 346          *
 347          * @param string $saveName - the destination filename
 348          * @param string $tempName - the source temporary file to save
 349          * @return string - full path the stashed file, or false on failure
 350          * @access private
 351          */
 352         function saveTempUploadedFile( $saveName, $tempName ) {
 353                 global $wgOut;
 354                 $archive = wfImageArchiveDir( $saveName, 'temp' );
 355                 $stash = $archive . '/' . gmdate( "YmdHis" ) . '!' . $saveName;
 356
 357                 if ( !move_uploaded_file( $tempName, $stash ) ) {
 358                         $wgOut->fileCopyError( $tempName, $stash );
 359                         return false;
 360                 }
 361
 362                 return $stash;
 363         }
 364
 365         /**
 366          * Stash a file in a temporary directory for later processing,
 367          * and save the necessary descriptive info into the session.
 368          * Returns a key value which will be passed through a form
 369          * to pick up the path info on a later invocation.
 370          *
 371          * @return int
 372          * @access private
 373          */
 374         function stashSession() {
 375                 $stash = $this->saveTempUploadedFile(
 376                         $this->mUploadSaveName, $this->mUploadTempName );
 377
 378                 if( !$stash ) {
 379                         # Couldn't save the file.
 380                         return false;
 381                 }
 382
 383                 $key = mt_rand( 0, 0x7fffffff );
 384                 $_SESSION['wsUploadData'][$key] = array(
 385                         'mUploadTempName' => $stash,
 386                         'mUploadSize'     => $this->mUploadSize,
 387                         'mOname'          => $this->mOname );
 388                 return $key;
 389         }
 390
 391         /**
 392          * Remove a temporarily kept file stashed by saveTempUploadedFile().
 393          * @access private
 394          */
 395         function unsaveUploadedFile() {
 396                 wfSuppressWarnings();
 397                 $success = unlink( $this->mUploadTempName );
 398                 wfRestoreWarnings();
 399                 if ( ! $success ) {
 400                         $wgOut->fileDeleteError( $this->mUploadTempName );
 401                 }
 402         }
 403
 404         /* -------------------------------------------------------------- */
 405
 406         /**
 407          * Show some text and linkage on successful upload.
 408          * @access private
 409          */
 410         function showSuccess() {
 411                 global $wgUser, $wgOut, $wgContLang;
 412
 413                 $sk = $wgUser->getSkin();
 414                 $ilink = $sk->makeMediaLink( $this->mUploadSaveName, Image::wfImageUrl( $this->mUploadSaveName ) );
 415                 $dname = $wgContLang->getNsText( NS_IMAGE ) . ':'.$this->mUploadSaveName;
 416                 $dlink = $sk->makeKnownLink( $dname, $dname );
 417
 418                 $wgOut->addHTML( '<h2>' . wfMsg( 'successfulupload' ) . "</h2>\n" );
 419                 $text = wfMsg( 'fileuploaded', $ilink, $dlink );
 420                 $wgOut->addHTML( '<p>'.$text."\n" );
 421                 $wgOut->returnToMain( false );
 422         }
 423
 424         /**
 425          * @param string $error as HTML
 426          * @access private
 427          */
 428         function uploadError( $error ) {
 429                 global $wgOut;
 430                 $sub = wfMsg( 'uploadwarning' );
 431                 $wgOut->addHTML( "<h2>{$sub}</h2>\n" );
 432                 $wgOut->addHTML( "<h4 class='error'>{$error}</h4>\n" );
 433         }
 434
 435         /**
 436          * There's something wrong with this file, not enough to reject it
 437          * totally but we require manual intervention to save it for real.
 438          * Stash it away, then present a form asking to confirm or cancel.
 439          *
 440          * @param string $warning as HTML
 441          * @access private
 442          */
 443         function uploadWarning( $warning ) {
 444                 global $wgOut, $wgUser, $wgLang, $wgUploadDirectory, $wgRequest;
 445                 global $wgUseCopyrightUpload;
 446
 447                 $this->mSessionKey = $this->stashSession();
 448                 if( !$this->mSessionKey ) {
 449                         # Couldn't save file; an error has been displayed so let's go.
 450                         return;
 451                 }
 452
 453                 $sub = wfMsg( 'uploadwarning' );
 454                 $wgOut->addHTML( "<h2>{$sub}</h2>\n" );
 455                 $wgOut->addHTML( "<ul class='warning'>{$warning}</ul><br />\n" );
 456
 457                 $save = wfMsg( 'savefile' );
 458                 $reupload = wfMsg( 'reupload' );
 459                 $iw = wfMsg( 'ignorewarning' );
 460                 $reup = wfMsg( 'reuploaddesc' );
 461                 $titleObj = Title::makeTitle( NS_SPECIAL, 'Upload' );
 462                 $action = $titleObj->escapeLocalURL( 'action=submit' );
 463
 464                 if ( $wgUseCopyrightUpload )
 465                 {
 466                         $copyright =  "
 467         <input type='hidden' name='wpUploadCopyStatus' value=\"" . htmlspecialchars( $this->mUploadCopyStatus ) . "\" />
 468         <input type='hidden' name='wpUploadSource' value=\"" . htmlspecialchars( $this->mUploadSource ) . "\" />
 469         ";
 470                 } else {
 471                         $copyright = "";
 472                 }
 473
 474                 $wgOut->addHTML( "
 475         <form id='uploadwarning' method='post' enctype='multipart/form-data' action='$action'>
 476                 <input type='hidden' name='wpUploadAffirm' value='1' />
 477                 <input type='hidden' name='wpIgnoreWarning' value='1' />
 478                 <input type='hidden' name='wpSessionKey' value=\"" . htmlspecialchars( $this->mSessionKey ) . "\" />
 479                 <input type='hidden' name='wpUploadDescription' value=\"" . htmlspecialchars( $this->mUploadDescription ) . "\" />
 480         {$copyright}
 481         <table border='0'>
 482                 <tr>
 483                         <tr>
 484                                 <td align='right'>
 485                                         <input tabindex='2' type='submit' name='wpUpload' value='$save' />
 486                                 </td>
 487                                 <td align='left'>$iw</td>
 488                         </tr>
 489                         <tr>
 490                                 <td align='right'>
 491                                         <input tabindex='2' type='submit' name='wpReUpload' value='{$reupload}' />
 492                                 </td>
 493                                 <td align='left'>$reup</td>
 494                         </tr>
 495                 </tr>
 496         </table></form>\n" );
 497         }
 498
 499         /**
 500          * Displays the main upload form, optionally with a highlighted
 501          * error message up at the top.
 502          *
 503          * @param string $msg as HTML
 504          * @access private
 505          */
 506         function mainUploadForm( $msg='' ) {
 507                 global $wgOut, $wgUser, $wgLang, $wgUploadDirectory, $wgRequest;
 508                 global $wgUseCopyrightUpload;
 509
 510                 $cols = intval($wgUser->getOption( 'cols' ));
 511                 $ew = $wgUser->getOption( 'editwidth' );
 512                 if ( $ew ) $ew = " style=\"width:100%\"";
 513                 else $ew = '';
 514
 515                 if ( '' != $msg ) {
 516                         $sub = wfMsg( 'uploaderror' );
 517                         $wgOut->addHTML( "<h2>{$sub}</h2>\n" .
 518                           "<h4 class='error'>{$msg}</h4>\n" );
 519                 } else {
 520                         $sub = wfMsg( 'uploadfile' );
 521                         $wgOut->addHTML( "<h2>{$sub}</h2>\n" );
 522                 }
 523                 $wgOut->addWikiText( wfMsg( 'uploadtext' ) );
 524                 $sk = $wgUser->getSkin();
 525
 526                 $fn = wfMsg( 'filename' );
 527                 $fd = wfMsg( 'filedesc' );
 528                 $ulb = wfMsg( 'uploadbtn' );
 529
 530                 $clink = $sk->makeKnownLink( wfMsgForContent( 'copyrightpage' ),
 531                   wfMsg( 'copyrightpagename' ) );
 532                 $ca = wfMsg( 'affirmation', $clink );
 533                 $iw = wfMsg( 'ignorewarning' );
 534
 535                 $titleObj = Title::makeTitle( NS_SPECIAL, 'Upload' );
 536                 $action = $titleObj->escapeLocalURL();
 537
 538                 $source = "
 539         <td align='right'>
 540         <input tabindex='3' type='checkbox' name='wpUploadAffirm' value='1' id='wpUploadAffirm' />
 541         </td><td align='left'><label for='wpUploadAffirm'>{$ca}</label></td>
 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         <td align='right'>{$fn}:</td><td align='left'>
 560         <input tabindex='1' type='file' name='wpUploadFile' size='40' />
 561         </td></tr><tr>
 562         <td align='right'>{$fd}:</td><td align='left'>
 563         <textarea tabindex='2' name='wpUploadDescription' rows='6' cols='{$cols}'{$ew}>"
 564           . htmlspecialchars( $this->mUploadDescription ) .
 565         "</textarea>
 566         </td></tr><tr>
 567         {$source}
 568         </tr>
 569         <tr><td></td><td align='left'>
 570         <input tabindex='5' type='submit' name='wpUpload' value=\"{$ulb}\" />
 571         </td></tr></table></form>\n" );
 572         }
 573
 574         /* -------------------------------------------------------------- */
 575
 576         /**
 577          * Split a file into a base name and all dot-delimited 'extensions'
 578          * on the end. Some web server configurations will fall back to
 579          * earlier pseudo-'extensions' to determine type and execute
 580          * scripts, so the blacklist needs to check them all.
 581          *
 582          * @return array
 583          */
 584         function splitExtensions( $filename ) {
 585                 $bits = explode( '.', $filename );
 586                 $basename = array_shift( $bits );
 587                 return array( $basename, $bits );
 588         }
 589
 590         /**
 591          * Perform case-insensitive match against a list of file extensions.
 592          * Returns true if the extension is in the list.
 593          *
 594          * @param string $ext
 595          * @param array $list
 596          * @return bool
 597          */
 598         function checkFileExtension( $ext, $list ) {
 599                 return in_array( strtolower( $ext ), $list );
 600         }
 601
 602         /**
 603          * Perform case-insensitive match against a list of file extensions.
 604          * Returns true if any of the extensions are in the list.
 605          *
 606          * @param array $ext
 607          * @param array $list
 608          * @return bool
 609          */
 610         function checkFileExtensionList( $ext, $list ) {
 611                 foreach( $ext as $e ) {
 612                         if( in_array( strtolower( $e ), $list ) ) {
 613                                 return true;
 614                         }
 615                 }
 616                 return false;
 617         }
 618
 619         /**
 620          * Returns false if the file is of a known type but can't be recognized,
 621          * indicating a corrupt file.
 622          * Returns true otherwise; unknown file types are not checked if given
 623          * with an unrecognized extension.
 624          *
 625          * @param string $tmpfile Pathname to the temporary upload file
 626          * @param string $extension The filename extension that the file is to be served with
 627          * @return bool
 628          */
 629         function verify( $tmpfile, $extension ) {
 630                 if( $this->triggersIEbug( $tmpfile ) ||
 631                     $this->triggersSafariBug( $tmpfile ) ) {
 632                         return false;
 633                 }
 634
 635                 $fname = 'SpecialUpload::verify';
 636                 $mergeExtensions = array(
 637                         'jpg' => 'jpeg',
 638                         'tif' => 'tiff' );
 639                 $extensionTypes = array(
 640                         # See http://www.php.net/getimagesize
 641                         1 => 'gif',
 642                         2 => 'jpeg',
 643                         3 => 'png',
 644                         4 => 'swf',
 645                         5 => 'psd',
 646                         6 => 'bmp',
 647                         7 => 'tiff',
 648                         8 => 'tiff',
 649                         9 => 'jpc',
 650                         10 => 'jp2',
 651                         11 => 'jpx',
 652                         12 => 'jb2',
 653                         13 => 'swc',
 654                         14 => 'iff',
 655                         15 => 'wbmp',
 656                         16 => 'xbm' );
 657
 658                 $extension = strtolower( $extension );
 659                 if( isset( $mergeExtensions[$extension] ) ) {
 660                         $extension = $mergeExtensions[$extension];
 661                 }
 662                 wfDebug( "$fname: Testing file '$tmpfile' with given extension '$extension'\n" );
 663
 664                 if( !in_array( $extension, $extensionTypes ) ) {
 665                         # Not a recognized image type. We don't know how to verify these.
 666                         # They're allowed by policy or they wouldn't get this far, so we'll
 667                         # let them slide for now.
 668                         wfDebug( "$fname: Unknown extension; passing.\n" );
 669                         return true;
 670                 }
 671
 672                 wfSuppressWarnings();
 673                 $data = getimagesize( $tmpfile );
 674                 wfRestoreWarnings();
 675                 if( false === $data ) {
 676                         # Didn't recognize the image type.
 677                         # Either the image is corrupt or someone's slipping us some
 678                         # bogus data such as HTML+JavaScript trying to take advantage
 679                         # of an Internet Explorer security flaw.
 680                         wfDebug( "$fname: getimagesize() doesn't recognize the file; rejecting.\n" );
 681                         return false;
 682                 }
 683
 684                 $imageType = $data[2];
 685                 if( !isset( $extensionTypes[$imageType] ) ) {
 686                         # Now we're kind of confused. Perhaps new image types added
 687                         # to PHP's support that we don't know about.
 688                         # We'll let these slide for now.
 689                         wfDebug( "$fname: getimagesize() knows the file, but we don't recognize the type; passing.\n" );
 690                         return true;
 691                 }
 692
 693                 $ext = strtolower( $extension );
 694                 if( $extension != $extensionTypes[$imageType] ) {
 695                         # The given filename extension doesn't match the
 696                         # file type. Probably just a mistake, but it's a stupid
 697                         # one and we shouldn't let it pass. KILL THEM!
 698                         wfDebug( "$fname: file extension does not match recognized type; rejecting.\n" );
 699                         return false;
 700                 }
 701
 702                 wfDebug( "$fname: all clear; passing.\n" );
 703                 return true;
 704         }
 705
 706         /**
 707          * Internet Explorer for Windows performs some really stupid file type
 708          * autodetection which can cause it to interpret valid image files as HTML
 709          * and potentially execute JavaScript, creating a cross-site scripting
 710          * attack vectors.
 711          *
 712          * Returns true if IE is likely to mistake the given file for HTML.
 713          *
 714          * @param string $filename
 715          * @return bool
 716          */
 717         function triggersIEbug( $filename ) {
 718                 $file = fopen( $filename, 'rb' );
 719                 $chunk = strtolower( fread( $file, 256 ) );
 720                 fclose( $file );
 721
 722                 $tags = array(
 723                         '<body',
 724                         '<head',
 725                         '<html',
 726                         '<img',
 727                         '<pre',
 728                         '<script',
 729                         '<table',
 730                         '<title' );
 731                 foreach( $tags as $tag ) {
 732                         if( false !== strpos( $chunk, $tag ) ) {
 733                                 return true;
 734                         }
 735                 }
 736                 return false;
 737         }
 738
 739         /**
 740          * Apple's Safari browser performs some unsafe file type autodetection
 741          * which can cause legitimate files to be interpreted as HTML if the
 742          * web server is not correctly configured to send the right content-type
 743          * (or if you're really uploading plain text and octet streams!)
 744          *
 745          * Returns true if Safari would mistake the given file for HTML
 746          * when served with a generic content-type.
 747          *
 748          * @param string $filename
 749          * @return bool
 750          */
 751         function triggersSafariBug( $filename ) {
 752                 $file = fopen( $filename, 'rb' );
 753                 $chunk = strtolower( fread( $file, 1024 ) );
 754                 fclose( $file );
 755
 756                 $tags = array(
 757                         '<html',
 758                         '<script',
 759                         '<title' );
 760                 foreach( $tags as $tag ) {
 761                         if( false !== strpos( $chunk, $tag ) ) {
 762                                 return true;
 763                         }
 764                 }
 765                 return false;
 766         }
 767
 768 }
 769 ?>