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authorPierre Schmitz <pierre@archlinux.de>2010-07-28 11:52:48 +0200
committerPierre Schmitz <pierre@archlinux.de>2010-07-28 11:52:48 +0200
commit222b01f5169f1c7e69762e0e8904c24f78f71882 (patch)
tree8e932e12546bb991357ec48eb1638d1770be7a35 /includes/upload/UploadBase.php
parent00ab76a6b686e98a914afc1975812d2b1aaa7016 (diff)
update to MediaWiki 1.16.0
Diffstat (limited to 'includes/upload/UploadBase.php')
-rw-r--r--includes/upload/UploadBase.php1091
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 );
+ }
+
+}