update to MediaWiki 1.16.0

1 files changed, 1091 insertions, 0 deletions

diff --git a/includes/upload/UploadBase.php b/includes/upload/UploadBase.php
new file mode 100644
index 00000000..5d955b36
--- /dev/null
+++ b/includes/upload/UploadBase.php
@@ -0,0 +1,1091 @@
+<?php
+/**
+ * @file
+ * @ingroup upload
+ *
+ * UploadBase and subclasses are the backend of MediaWiki's file uploads.
+ * The frontends are formed by ApiUpload and SpecialUpload.
+ *
+ * See also includes/docs/upload.txt
+ *
+ * @author Brion Vibber
+ * @author Bryan Tong Minh
+ * @author Michael Dale
+ */
+
+abstract class UploadBase {
+	protected $mTempPath;
+	protected $mDesiredDestName, $mDestName, $mRemoveTempFile, $mSourceType;
+	protected $mTitle = false, $mTitleError = 0;
+	protected $mFilteredName, $mFinalExtension;
+	protected $mLocalFile;
+
+	const SUCCESS = 0;
+	const OK = 0;
+	const EMPTY_FILE = 3;
+	const MIN_LENGTH_PARTNAME = 4;
+	const ILLEGAL_FILENAME = 5;
+	const OVERWRITE_EXISTING_FILE = 7;
+	const FILETYPE_MISSING = 8;
+	const FILETYPE_BADTYPE = 9;
+	const VERIFICATION_ERROR = 10;
+	const UPLOAD_VERIFICATION_ERROR = 11;
+	const HOOK_ABORTED = 11;
+
+	const SESSION_VERSION = 2;
+
+	/**
+	 * Returns true if uploads are enabled.
+	 * Can be override by subclasses.
+	 */
+	public static function isEnabled() {
+		global $wgEnableUploads;
+		if ( !$wgEnableUploads ) {
+			return false;
+		}
+
+		# Check php's file_uploads setting
+		if( !wfIniGetBool( 'file_uploads' ) ) {
+			return false;
+		}
+		return true;
+	}
+
+	/**
+	 * Returns true if the user can use this upload module or else a string
+	 * identifying the missing permission.
+	 * Can be overriden by subclasses.
+	 */
+	public static function isAllowed( $user ) {
+		if( !$user->isAllowed( 'upload' ) ) {
+			return 'upload';
+		}
+		return true;
+	}
+
+	// Upload handlers. Should probably just be a global.
+	static $uploadHandlers = array( 'Stash', 'File', 'Url' );
+
+	/**
+	 * Create a form of UploadBase depending on wpSourceType and initializes it
+	 */
+	public static function createFromRequest( &$request, $type = null ) {
+		$type = $type ? $type : $request->getVal( 'wpSourceType', 'File' );
+
+		if( !$type ) {
+			return null;
+		}
+
+		// Get the upload class
+		$type = ucfirst( $type );
+
+		// Give hooks the chance to handle this request
+		$className = null;
+		wfRunHooks( 'UploadCreateFromRequest', array( $type, &$className ) );
+		if ( is_null( $className ) ) {
+			$className = 'UploadFrom' . $type;
+			wfDebug( __METHOD__ . ": class name: $className\n" );
+			if( !in_array( $type, self::$uploadHandlers ) ) {
+				return null;
+			}
+		}
+
+		// Check whether this upload class is enabled
+		if( !call_user_func( array( $className, 'isEnabled' ) ) ) {
+			return null;
+		}
+
+		// Check whether the request is valid
+		if( !call_user_func( array( $className, 'isValidRequest' ), $request ) ) {
+			return null;
+		}
+
+		$handler = new $className;
+
+		$handler->initializeFromRequest( $request );
+		return $handler;
+	}
+
+	/**
+	 * Check whether a request if valid for this handler
+	 */
+	public static function isValidRequest( $request ) {
+		return false;
+	}
+
+	public function __construct() {}
+
+	/**
+	 * Initialize the path information
+	 * @param $name string the desired destination name
+	 * @param $tempPath string the temporary path
+	 * @param $fileSize int the file size
+	 * @param $removeTempFile bool (false) remove the temporary file?
+	 * @return null
+	 */
+	public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
+		$this->mDesiredDestName = $name;
+		$this->mTempPath = $tempPath;
+		$this->mFileSize = $fileSize;
+		$this->mRemoveTempFile = $removeTempFile;
+	}
+
+	/**
+	 * Initialize from a WebRequest. Override this in a subclass.
+	 */
+	public abstract function initializeFromRequest( &$request );
+
+	/**
+	 * Fetch the file. Usually a no-op
+	 */
+	public function fetchFile() {
+		return Status::newGood();
+	}
+
+	/**
+	 * Return the file size
+	 */
+	public function isEmptyFile() {
+		return empty( $this->mFileSize );
+	}
+
+	/**
+	 * @param string $srcPath the source path
+	 * @returns the real path if it was a virtual URL
+	 */
+	function getRealPath( $srcPath ) {
+		$repo = RepoGroup::singleton()->getLocalRepo();
+		if ( $repo->isVirtualUrl( $srcPath ) ) {
+			return $repo->resolveVirtualUrl( $srcPath );
+		}
+		return $srcPath;
+	}
+
+	/**
+	 * Verify whether the upload is sane.
+	 * Returns self::OK or else an array with error information
+	 */
+	public function verifyUpload() {
+		/**
+		 * If there was no filename or a zero size given, give up quick.
+		 */
+		if( $this->isEmptyFile() ) {
+			return array( 'status' => self::EMPTY_FILE );
+		}
+
+		/**
+		 * Look at the contents of the file; if we can recognize the
+		 * type but it's corrupt or data of the wrong type, we should
+		 * probably not accept it.
+		 */
+		$verification = $this->verifyFile();
+		if( $verification !== true ) {
+			if( !is_array( $verification ) ) {
+				$verification = array( $verification );
+			}
+			return array(
+				'status' => self::VERIFICATION_ERROR,
+				'details' => $verification
+			);
+		}
+
+		$nt = $this->getTitle();
+		if( is_null( $nt ) ) {
+			$result = array( 'status' => $this->mTitleError );
+			if( $this->mTitleError == self::ILLEGAL_FILENAME ) {
+				$result['filtered'] = $this->mFilteredName;
+			}
+			if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
+				$result['finalExt'] = $this->mFinalExtension;
+			}
+			return $result;
+		}
+		$this->mDestName = $this->getLocalFile()->getName();
+
+		/**
+		 * In some cases we may forbid overwriting of existing files.
+		 */
+		$overwrite = $this->checkOverwrite();
+		if( $overwrite !== true ) {
+			return array(
+				'status' => self::OVERWRITE_EXISTING_FILE,
+				'overwrite' => $overwrite
+			);
+		}
+
+		$error = '';
+		if( !wfRunHooks( 'UploadVerification',
+				array( $this->mDestName, $this->mTempPath, &$error ) ) ) {
+			// This status needs another name...
+			return array( 'status' => self::HOOK_ABORTED, 'error' => $error );
+		}
+
+		return array( 'status' => self::OK );
+	}
+
+	/**
+	 * Verifies that it's ok to include the uploaded file
+	 *
+	 * @return mixed true of the file is verified, a string or array otherwise.
+	 */
+	protected function verifyFile() {
+		$this->mFileProps = File::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
+		$this->checkMacBinary();
+
+		# magically determine mime type
+		$magic = MimeMagic::singleton();
+		$mime = $magic->guessMimeType( $this->mTempPath, false );
+
+		# check mime type, if desired
+		global $wgVerifyMimeType;
+		if ( $wgVerifyMimeType ) {
+			wfDebug ( "\n\nmime: <$mime> extension: <{$this->mFinalExtension}>\n\n");
+			if ( !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
+				return array( 'filetype-mime-mismatch' );
+			}
+
+			global $wgMimeTypeBlacklist;
+			if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
+				return array( 'filetype-badmime', $mime );
+			}
+
+			# Check IE type
+			$fp = fopen( $this->mTempPath, 'rb' );
+			$chunk = fread( $fp, 256 );
+			fclose( $fp );
+			$extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
+			$ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
+			foreach ( $ieTypes as $ieType ) {
+				if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
+					return array( 'filetype-bad-ie-mime', $ieType );
+				}
+			}
+		}
+
+		# check for htmlish code and javascript
+		if( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
+			return 'uploadscripted';
+		}
+		if( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
+			if( self::detectScriptInSvg( $this->mTempPath ) ) {
+				return 'uploadscripted';
+			}
+		}
+
+		/**
+		* Scan the uploaded file for viruses
+		*/
+		$virus = $this->detectVirus( $this->mTempPath );
+		if ( $virus ) {
+			return array( 'uploadvirus', $virus );
+		}
+		wfDebug( __METHOD__ . ": all clear; passing.\n" );
+		return true;
+	}
+
+	/**
+	 * Check whether the user can edit, upload and create the image.
+	 *
+	 * @param User $user the user to verify the permissions against
+	 * @return mixed An array as returned by getUserPermissionsErrors or true
+	 *               in case the user has proper permissions.
+	 */
+	public function verifyPermissions( $user ) {
+		/**
+		 * If the image is protected, non-sysop users won't be able
+		 * to modify it by uploading a new revision.
+		 */
+		$nt = $this->getTitle();
+		if( is_null( $nt ) ) {
+			return true;
+		}
+		$permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
+		$permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
+		$permErrorsCreate = ( $nt->exists() ? array() : $nt->getUserPermissionsErrors( 'create', $user ) );
+		if( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
+			$permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
+			$permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
+			return $permErrors;
+		}
+		return true;
+	}
+
+	/**
+	 * Check for non fatal problems with the file
+	 *
+	 * @return array Array of warnings
+	 */
+	public function checkWarnings() {
+		$warnings = array();
+
+		$localFile = $this->getLocalFile();
+		$filename = $localFile->getName();
+		$n = strrpos( $filename, '.' );
+		$partname = $n ? substr( $filename, 0, $n ) : $filename;
+
+		/**
+		 * Check whether the resulting filename is different from the desired one,
+		 * but ignore things like ucfirst() and spaces/underscore things
+		 */
+		$comparableName = str_replace( ' ', '_', $this->mDesiredDestName );
+		$comparableName = Title::capitalize( $comparableName, NS_FILE );
+
+		if( $this->mDesiredDestName != $filename && $comparableName != $filename ) {
+			$warnings['badfilename'] = $filename;
+		}
+
+		// Check whether the file extension is on the unwanted list
+		global $wgCheckFileExtensions, $wgFileExtensions;
+		if ( $wgCheckFileExtensions ) {
+			if ( !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) {
+				$warnings['filetype-unwanted-type'] = $this->mFinalExtension;
+			}
+		}
+
+		global $wgUploadSizeWarning;
+		if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) ) {
+			$warnings['large-file'] = $wgUploadSizeWarning;
+		}
+
+		if ( $this->mFileSize == 0 ) {
+			$warnings['emptyfile'] = true;
+		}
+
+		$exists = self::getExistsWarning( $localFile );
+		if( $exists !== false ) {
+			$warnings['exists'] = $exists;
+		}
+
+		// Check dupes against existing files
+		$hash = File::sha1Base36( $this->mTempPath );
+		$dupes = RepoGroup::singleton()->findBySha1( $hash );
+		$title = $this->getTitle();
+		// Remove all matches against self
+		foreach ( $dupes as $key => $dupe ) {
+			if( $title->equals( $dupe->getTitle() ) ) {
+				unset( $dupes[$key] );
+			}
+		}
+		if( $dupes ) {
+			$warnings['duplicate'] = $dupes;
+		}
+
+		// Check dupes against archives
+		$archivedImage = new ArchivedFile( null, 0, "{$hash}.{$this->mFinalExtension}" );
+		if ( $archivedImage->getID() > 0 ) {
+			$warnings['duplicate-archive'] = $archivedImage->getName();
+		}
+
+		return $warnings;
+	}
+
+	/**
+	 * Really perform the upload. Stores the file in the local repo, watches
+	 * if necessary and runs the UploadComplete hook.
+	 *
+	 * @return mixed Status indicating the whether the upload succeeded.
+	 */
+	public function performUpload( $comment, $pageText, $watch, $user ) {
+		wfDebug( "\n\n\performUpload: sum:" . $comment . ' c: ' . $pageText . ' w:' . $watch );
+		$status = $this->getLocalFile()->upload( $this->mTempPath, $comment, $pageText,
+			File::DELETE_SOURCE, $this->mFileProps, false, $user );
+
+		if( $status->isGood() && $watch ) {
+			$user->addWatch( $this->getLocalFile()->getTitle() );
+		}
+
+		if( $status->isGood() ) {
+			wfRunHooks( 'UploadComplete', array( &$this ) );
+		}
+
+		return $status;
+	}
+
+	/**
+	 * Returns the title of the file to be uploaded. Sets mTitleError in case
+	 * the name was illegal.
+	 *
+	 * @return Title The title of the file or null in case the name was illegal
+	 */
+	public function getTitle() {
+		if ( $this->mTitle !== false ) {
+			return $this->mTitle;
+		}
+
+		/**
+		 * Chop off any directories in the given filename. Then
+		 * filter out illegal characters, and try to make a legible name
+		 * out of it. We'll strip some silently that Title would die on.
+		 */
+		$basename = $this->mDesiredDestName;
+
+		$this->mFilteredName = wfStripIllegalFilenameChars( $basename );
+		/* Normalize to title form before we do any further processing */
+		$nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
+		if( is_null( $nt ) ) {
+			$this->mTitleError = self::ILLEGAL_FILENAME;
+			return $this->mTitle = null;
+		}
+		$this->mFilteredName = $nt->getDBkey();
+
+		/**
+		 * We'll want to blacklist against *any* 'extension', and use
+		 * only the final one for the whitelist.
+		 */
+		list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
+
+		if( count( $ext ) ) {
+			$this->mFinalExtension = trim( $ext[count( $ext ) - 1] );
+		} else {
+			$this->mFinalExtension = '';
+		}
+
+		/* Don't allow users to override the blacklist (check file extension) */
+		global $wgCheckFileExtensions, $wgStrictFileExtensions;
+		global $wgFileExtensions, $wgFileBlacklist;
+		if ( $this->mFinalExtension == '' ) {
+			$this->mTitleError = self::FILETYPE_MISSING;
+			return $this->mTitle = null;
+		} elseif ( $this->checkFileExtensionList( $ext, $wgFileBlacklist ) ||
+				( $wgCheckFileExtensions && $wgStrictFileExtensions &&
+					!$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) ) {
+			$this->mTitleError = self::FILETYPE_BADTYPE;
+			return $this->mTitle = null;
+		}
+
+		# If there was more than one "extension", reassemble the base
+		# filename to prevent bogus complaints about length
+		if( count( $ext ) > 1 ) {
+			for( $i = 0; $i < count( $ext ) - 1; $i++ ) {
+				$partname .= '.' . $ext[$i];
+			}
+		}
+
+		if( strlen( $partname ) < 1 ) {
+			$this->mTitleError =  self::MIN_LENGTH_PARTNAME;
+			return $this->mTitle = null;
+		}
+
+		$nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
+		if( is_null( $nt ) ) {
+			$this->mTitleError = self::ILLEGAL_FILENAME;
+			return $this->mTitle = null;
+		}
+		return $this->mTitle = $nt;
+	}
+
+	/**
+	 * Return the local file and initializes if necessary.
+	 */
+	public function getLocalFile() {
+		if( is_null( $this->mLocalFile ) ) {
+			$nt = $this->getTitle();
+			$this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
+		}
+		return $this->mLocalFile;
+	}
+
+	/**
+	 * Stash a file in a temporary directory for later processing
+	 * after the user has confirmed it.
+	 *
+	 * If the user doesn't explicitly cancel or accept, these files
+	 * can accumulate in the temp directory.
+	 *
+	 * @param string $saveName - the destination filename
+	 * @param string $tempSrc - the source temporary file to save
+	 * @return string - full path the stashed file, or false on failure
+	 */
+	protected function saveTempUploadedFile( $saveName, $tempSrc ) {
+		$repo = RepoGroup::singleton()->getLocalRepo();
+		$status = $repo->storeTemp( $saveName, $tempSrc );
+		return $status;
+	}
+
+	/**
+	 * Stash a file in a temporary directory for later processing,
+	 * and save the necessary descriptive info into the session.
+	 * Returns a key value which will be passed through a form
+	 * to pick up the path info on a later invocation.
+	 *
+	 * @return int Session key
+	 */
+	public function stashSession() {
+		$status = $this->saveTempUploadedFile( $this->mDestName, $this->mTempPath );
+		if( !$status->isOK() ) {
+			# Couldn't save the file.
+			return false;
+		}
+		if( !isset( $_SESSION ) ) {
+			session_start(); // start up the session (might have been previously closed to prevent php session locking)
+		}
+		$key = $this->getSessionKey();
+		$_SESSION['wsUploadData'][$key] = array(
+			'mTempPath'       => $status->value,
+			'mFileSize'       => $this->mFileSize,
+			'mFileProps'      => $this->mFileProps,
+			'version'         => self::SESSION_VERSION,
+		);
+		return $key;
+	}
+
+	/**
+	 * Generate a random session key from stash in cases where we want to start an upload without much information
+	 */
+	protected function getSessionKey() {
+		$key = mt_rand( 0, 0x7fffffff );
+		$_SESSION['wsUploadData'][$key] = array();
+		return $key;
+	}
+
+	/**
+	 * If we've modified the upload file we need to manually remove it
+	 * on exit to clean up.
+	 */
+	public function cleanupTempFile() {
+		if ( $this->mRemoveTempFile && $this->mTempPath && file_exists( $this->mTempPath ) ) {
+			wfDebug( __METHOD__ . ": Removing temporary file {$this->mTempPath}\n" );
+			unlink( $this->mTempPath );
+		}
+	}
+
+	public function getTempPath() {
+		return $this->mTempPath;
+	}
+
+	/**
+	 * Split a file into a base name and all dot-delimited 'extensions'
+	 * on the end. Some web server configurations will fall back to
+	 * earlier pseudo-'extensions' to determine type and execute
+	 * scripts, so the blacklist needs to check them all.
+	 *
+	 * @return array
+	 */
+	public static function splitExtensions( $filename ) {
+		$bits = explode( '.', $filename );
+		$basename = array_shift( $bits );
+		return array( $basename, $bits );
+	}
+
+	/**
+	 * Perform case-insensitive match against a list of file extensions.
+	 * Returns true if the extension is in the list.
+	 *
+	 * @param string $ext
+	 * @param array $list
+	 * @return bool
+	 */
+	public static function checkFileExtension( $ext, $list ) {
+		return in_array( strtolower( $ext ), $list );
+	}
+
+	/**
+	 * Perform case-insensitive match against a list of file extensions.
+	 * Returns true if any of the extensions are in the list.
+	 *
+	 * @param array $ext
+	 * @param array $list
+	 * @return bool
+	 */
+	public static function checkFileExtensionList( $ext, $list ) {
+		foreach( $ext as $e ) {
+			if( in_array( strtolower( $e ), $list ) ) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	/**
+	 * Checks if the mime type of the uploaded file matches the file extension.
+	 *
+	 * @param string $mime the mime type of the uploaded file
+	 * @param string $extension The filename extension that the file is to be served with
+	 * @return bool
+	 */
+	public static function verifyExtension( $mime, $extension ) {
+		$magic = MimeMagic::singleton();
+
+		if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' )
+			if ( !$magic->isRecognizableExtension( $extension ) ) {
+				wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
+					"unrecognized extension '$extension', can't verify\n" );
+				return true;
+			} else {
+				wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; ".
+					"recognized extension '$extension', so probably invalid file\n" );
+				return false;
+			}
+
+		$match = $magic->isMatchingExtension( $extension, $mime );
+
+		if ( $match === null ) {
+			wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
+			return true;
+		} elseif( $match === true ) {
+			wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
+
+			#TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
+			return true;
+
+		} else {
+			wfDebug( __METHOD__ . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
+			return false;
+		}
+	}
+
+	/**
+	 * Heuristic for detecting files that *could* contain JavaScript instructions or
+	 * things that may look like HTML to a browser and are thus
+	 * potentially harmful. The present implementation will produce false
+	 * positives in some situations.
+	 *
+	 * @param string $file Pathname to the temporary upload file
+	 * @param string $mime The mime type of the file
+	 * @param string $extension The extension of the file
+	 * @return bool true if the file contains something looking like embedded scripts
+	 */
+	public static function detectScript( $file, $mime, $extension ) {
+		global $wgAllowTitlesInSVG;
+
+		# ugly hack: for text files, always look at the entire file.
+		# For binary field, just check the first K.
+
+		if( strpos( $mime,'text/' ) === 0 ) {
+			$chunk = file_get_contents( $file );
+		} else {
+			$fp = fopen( $file, 'rb' );
+			$chunk = fread( $fp, 1024 );
+			fclose( $fp );
+		}
+
+		$chunk = strtolower( $chunk );
+
+		if( !$chunk ) {
+			return false;
+		}
+
+		# decode from UTF-16 if needed (could be used for obfuscation).
+		if( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
+			$enc = 'UTF-16BE';
+		} elseif( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
+			$enc = 'UTF-16LE';
+		} else {
+			$enc = null;
+		}
+
+		if( $enc ) {
+			$chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
+		}
+
+		$chunk = trim( $chunk );
+
+		# FIXME: convert from UTF-16 if necessarry!
+		wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
+
+		# check for HTML doctype
+		if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
+			return true;
+		}
+
+		/**
+		 * Internet Explorer for Windows performs some really stupid file type
+		 * autodetection which can cause it to interpret valid image files as HTML
+		 * and potentially execute JavaScript, creating a cross-site scripting
+		 * attack vectors.
+		 *
+		 * Apple's Safari browser also performs some unsafe file type autodetection
+		 * which can cause legitimate files to be interpreted as HTML if the
+		 * web server is not correctly configured to send the right content-type
+		 * (or if you're really uploading plain text and octet streams!)
+		 *
+		 * Returns true if IE is likely to mistake the given file for HTML.
+		 * Also returns true if Safari would mistake the given file for HTML
+		 * when served with a generic content-type.
+		 */
+		$tags = array(
+			'<a href',
+			'<body',
+			'<head',
+			'<html',   #also in safari
+			'<img',
+			'<pre',
+			'<script', #also in safari
+			'<table'
+		);
+
+		if( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
+			$tags[] = '<title';
+		}
+
+		foreach( $tags as $tag ) {
+			if( false !== strpos( $chunk, $tag ) ) {
+				return true;
+			}
+		}
+
+		/*
+		 * look for JavaScript
+		 */
+
+		# resolve entity-refs to look at attributes. may be harsh on big files... cache result?
+		$chunk = Sanitizer::decodeCharReferences( $chunk );
+
+		# look for script-types
+		if( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
+			return true;
+		}
+
+		# look for html-style script-urls
+		if( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
+			return true;
+		}
+
+		# look for css-style script-urls
+		if( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
+			return true;
+		}
+
+		wfDebug( __METHOD__ . ": no scripts found\n" );
+		return false;
+	}
+
+	protected function detectScriptInSvg( $filename ) {
+		$check = new XmlTypeCheck( $filename, array( $this, 'checkSvgScriptCallback' ) );
+		return $check->filterMatch;
+	}
+
+	/**
+	 * @todo Replace this with a whitelist filter!
+	 */
+	public function checkSvgScriptCallback( $element, $attribs ) {
+		$stripped = $this->stripXmlNamespace( $element );
+
+		if( $stripped == 'script' ) {
+			wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
+			return true;
+		}
+
+		foreach( $attribs as $attrib => $value ) {
+			$stripped = $this->stripXmlNamespace( $attrib );
+			if( substr( $stripped, 0, 2 ) == 'on' ) {
+				wfDebug( __METHOD__ . ": Found script attribute '$attrib'='value' in uploaded file.\n" );
+				return true;
+			}
+			if( $stripped == 'href' && strpos( strtolower( $value ), 'javascript:' ) !== false ) {
+				wfDebug( __METHOD__ . ": Found script href attribute '$attrib'='$value' in uploaded file.\n" );
+				return true;
+			}
+		}
+	}
+
+	private function stripXmlNamespace( $name ) {
+		// 'http://www.w3.org/2000/svg:script' -> 'script'
+		$parts = explode( ':', strtolower( $name ) );
+		return array_pop( $parts );
+	}
+
+	/**
+	 * Generic wrapper function for a virus scanner program.
+	 * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
+	 * $wgAntivirusRequired may be used to deny upload if the scan fails.
+	 *
+	 * @param string $file Pathname to the temporary upload file
+	 * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
+	 *         or a string containing feedback from the virus scanner if a virus was found.
+	 *         If textual feedback is missing but a virus was found, this function returns true.
+	 */
+	public static function detectVirus( $file ) {
+		global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
+
+		if ( !$wgAntivirus ) {
+			wfDebug( __METHOD__ . ": virus scanner disabled\n" );
+			return null;
+		}
+
+		if ( !$wgAntivirusSetup[$wgAntivirus] ) {
+			wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
+			$wgOut->wrapWikiMsg( "<div class=\"error\">\n$1</div>", array( 'virus-badscanner', $wgAntivirus ) );
+			return wfMsg( 'virus-unknownscanner' ) . " $wgAntivirus";
+		}
+
+		# look up scanner configuration
+		$command = $wgAntivirusSetup[$wgAntivirus]['command'];
+		$exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
+		$msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ) ?
+			$wgAntivirusSetup[$wgAntivirus]['messagepattern'] : null;
+
+		if ( strpos( $command, "%f" ) === false ) {
+			# simple pattern: append file to scan
+			$command .= " " . wfEscapeShellArg( $file );
+		} else {
+			# complex pattern: replace "%f" with file to scan
+			$command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
+		}
+
+		wfDebug( __METHOD__ . ": running virus scan: $command \n" );
+
+		# execute virus scanner
+		$exitCode = false;
+
+		# NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
+		#      that does not seem to be worth the pain.
+		#      Ask me (Duesentrieb) about it if it's ever needed.
+		$output = wfShellExec( "$command 2>&1", $exitCode );
+
+		# map exit code to AV_xxx constants.
+		$mappedCode = $exitCode;
+		if ( $exitCodeMap ) {
+			if ( isset( $exitCodeMap[$exitCode] ) ) {
+				$mappedCode = $exitCodeMap[$exitCode];
+			} elseif ( isset( $exitCodeMap["*"] ) ) {
+				$mappedCode = $exitCodeMap["*"];
+			}
+		}
+
+		if ( $mappedCode === AV_SCAN_FAILED ) {
+			# scan failed (code was mapped to false by $exitCodeMap)
+			wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
+
+			if ( $wgAntivirusRequired ) {
+				return wfMsg( 'virus-scanfailed', array( $exitCode ) );
+			} else {
+				return null;
+			}
+		} elseif ( $mappedCode === AV_SCAN_ABORTED ) {
+			# scan failed because filetype is unknown (probably imune)
+			wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
+			return null;
+		} elseif ( $mappedCode === AV_NO_VIRUS ) {
+			# no virus found
+			wfDebug( __METHOD__ . ": file passed virus scan.\n" );
+			return false;
+		} else {
+			$output = trim( $output );
+
+			if ( !$output ) {
+				$output = true; #if there's no output, return true
+			} elseif ( $msgPattern ) {
+				$groups = array();
+				if ( preg_match( $msgPattern, $output, $groups ) ) {
+					if ( $groups[1] ) {
+						$output = $groups[1];
+					}
+				}
+			}
+
+			wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
+			return $output;
+		}
+	}
+
+	/**
+	 * Check if the temporary file is MacBinary-encoded, as some uploads
+	 * from Internet Explorer on Mac OS Classic and Mac OS X will be.
+	 * If so, the data fork will be extracted to a second temporary file,
+	 * which will then be checked for validity and either kept or discarded.
+	 */
+	private function checkMacBinary() {
+		$macbin = new MacBinary( $this->mTempPath );
+		if( $macbin->isValid() ) {
+			$dataFile = tempnam( wfTempDir(), 'WikiMacBinary' );
+			$dataHandle = fopen( $dataFile, 'wb' );
+
+			wfDebug( __METHOD__ . ": Extracting MacBinary data fork to $dataFile\n" );
+			$macbin->extractData( $dataHandle );
+
+			$this->mTempPath = $dataFile;
+			$this->mFileSize = $macbin->dataForkLength();
+
+			// We'll have to manually remove the new file if it's not kept.
+			$this->mRemoveTempFile = true;
+		}
+		$macbin->close();
+	}
+
+	/**
+	 * Check if there's an overwrite conflict and, if so, if restrictions
+	 * forbid this user from performing the upload.
+	 *
+	 * @return mixed true on success, error string on failure
+	 */
+	private function checkOverwrite() {
+		global $wgUser;
+		// First check whether the local file can be overwritten
+		$file = $this->getLocalFile();
+		if( $file->exists() ) {
+			if( !self::userCanReUpload( $wgUser, $file ) ) {
+				return 'fileexists-forbidden';
+			} else {
+				return true;
+			}
+		}
+
+		/* Check shared conflicts: if the local file does not exist, but
+		 * wfFindFile finds a file, it exists in a shared repository.
+		 */
+		$file = wfFindFile( $this->getTitle() );
+		if ( $file && !$wgUser->isAllowed( 'reupload-shared' ) ) {
+			return 'fileexists-shared-forbidden';
+		}
+
+		return true;
+	}
+
+	/**
+	 * Check if a user is the last uploader
+	 *
+	 * @param User $user
+	 * @param string $img, image name
+	 * @return bool
+	 */
+	public static function userCanReUpload( User $user, $img ) {
+		if( $user->isAllowed( 'reupload' ) ) {
+			return true; // non-conditional
+		}
+		if( !$user->isAllowed( 'reupload-own' ) ) {
+			return false;
+		}
+		if( is_string( $img ) ) {
+			$img = wfLocalFile( $img );
+		}
+		if ( !( $img instanceof LocalFile ) ) {
+			return false;
+		}
+
+		return $user->getId() == $img->getUser( 'id' );
+	}
+
+	/**
+	 * Helper function that does various existence checks for a file.
+	 * The following checks are performed:
+	 * - The file exists
+	 * - Article with the same name as the file exists
+	 * - File exists with normalized extension
+	 * - The file looks like a thumbnail and the original exists
+	 *
+	 * @param File $file The file to check
+	 * @return mixed False if the file does not exists, else an array
+	 */
+	public static function getExistsWarning( $file ) {
+		if( $file->exists() ) {
+			return array( 'warning' => 'exists', 'file' => $file );
+		}
+
+		if( $file->getTitle()->getArticleID() ) {
+			return array( 'warning' => 'page-exists', 'file' => $file );
+		}
+
+		if ( $file->wasDeleted() && !$file->exists() ) {
+			return array( 'warning' => 'was-deleted', 'file' => $file );
+		}
+
+		if( strpos( $file->getName(), '.' ) == false ) {
+			$partname = $file->getName();
+			$extension = '';
+		} else {
+			$n = strrpos( $file->getName(), '.' );
+			$extension = substr( $file->getName(), $n + 1 );
+			$partname = substr( $file->getName(), 0, $n );
+		}
+		$normalizedExtension = File::normalizeExtension( $extension );
+
+		if ( $normalizedExtension != $extension ) {
+			// We're not using the normalized form of the extension.
+			// Normal form is lowercase, using most common of alternate
+			// extensions (eg 'jpg' rather than 'JPEG').
+			//
+			// Check for another file using the normalized form...
+			$nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
+			$file_lc = wfLocalFile( $nt_lc );
+
+			if( $file_lc->exists() ) {
+				return array(
+					'warning' => 'exists-normalized',
+					'file' => $file,
+					'normalizedFile' => $file_lc
+				);
+			}
+		}
+
+		if ( self::isThumbName( $file->getName() ) ) {
+			# Check for filenames like 50px- or 180px-, these are mostly thumbnails
+			$nt_thb = Title::newFromText( substr( $partname , strpos( $partname , '-' ) +1 ) . '.' . $extension, NS_FILE );
+			$file_thb = wfLocalFile( $nt_thb );
+			if( $file_thb->exists() ) {
+				return array(
+					'warning' => 'thumb',
+					'file' => $file,
+					'thumbFile' => $file_thb
+				);
+			} else {
+				// File does not exist, but we just don't like the name
+				return array(
+					'warning' => 'thumb-name',
+					'file' => $file,
+					'thumbFile' => $file_thb
+				);
+			}
+		}
+
+
+		foreach( self::getFilenamePrefixBlacklist() as $prefix ) {
+			if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
+				return array(
+					'warning' => 'bad-prefix',
+					'file' => $file,
+					'prefix' => $prefix
+				);
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Helper function that checks whether the filename looks like a thumbnail
+	 */
+	public static function isThumbName( $filename ) {
+		$n = strrpos( $filename, '.' );
+		$partname = $n ? substr( $filename, 0, $n ) : $filename;
+		return (
+					substr( $partname , 3, 3 ) == 'px-' ||
+					substr( $partname , 2, 3 ) == 'px-'
+				) &&
+				preg_match( "/[0-9]{2}/" , substr( $partname , 0, 2 ) );
+	}
+
+	/**
+	 * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
+	 *
+	 * @return array list of prefixes
+	 */
+	public static function getFilenamePrefixBlacklist() {
+		$blacklist = array();
+		$message = wfMsgForContent( 'filename-prefix-blacklist' );
+		if( $message && !( wfEmptyMsg( 'filename-prefix-blacklist', $message ) || $message == '-' ) ) {
+			$lines = explode( "\n", $message );
+			foreach( $lines as $line ) {
+				// Remove comment lines
+				$comment = substr( trim( $line ), 0, 1 );
+				if ( $comment == '#' || $comment == '' ) {
+					continue;
+				}
+				// Remove additional comments after a prefix
+				$comment = strpos( $line, '#' );
+				if ( $comment > 0 ) {
+					$line = substr( $line, 0, $comment-1 );
+				}
+				$blacklist[] = trim( $line );
+			}
+		}
+		return $blacklist;
+	}
+
+	public function getImageInfo( $result ) {
+		$file = $this->getLocalFile();
+		$imParam = ApiQueryImageInfo::getPropertyNames();
+		return ApiQueryImageInfo::getInfo( $file, array_flip( $imParam ), $result );
+	}
+
+}