wiki.techinc.nl/img_auth.php
Jack D. Pond 81fad6027c bug 19646 Localization of img_auth.php - with enhancements
https://bugzilla.wikimedia.org/show_bug.cgi?id=19646

1. Localize img_auth.php using core messages
2. Reorder checks to make sense (and eliminate redundancy)n
3. Add hook 'ImgAuthBeforeStream' to allow custom checking
4. Add globals wgImgAuthDetails, 
5. Move all "wfDebugLog" into the rejection functions
2009-09-04 02:44:05 +00:00

114 lines
4.1 KiB
PHP

<?php
/**
* Image authorisation script
*
* To use this, see http://www.mediawiki.org/wiki/Manual:Image_Authorization
*
* - Set $wgUploadDirectory to a non-public directory (not web accessible)
* - Set $wgUploadPath to point to this file
*
* Optional Parameters
*
* - Set $wgImgAuthDetails = true if you want the reason the access was denied messages to be displayed
* instead of just the 403 error (doesn't work on IE anyway), otherwise will only appear in error logs
* - Set $wgImgAuthPublicTest false if you don't want to just check and see if all are public
* must be set to false if using specific restrictions such as LockDown or NSFileRepo
*
* For security reasons, you usually don't want your user to know *why* access was denied, just that it was.
* If you want to change this, you can set $wgImgAuthDetails to 'true' in localsettings.php and it will give the user the reason
* why access was denied.
*
* Your server needs to support PATH_INFO; CGI-based configurations usually don't.
*
* @file
*
**/
define( 'MW_NO_OUTPUT_COMPRESSION', 1 );
require_once( dirname( __FILE__ ) . '/includes/WebStart.php' );
wfProfileIn( 'img_auth.php' );
require_once( dirname( __FILE__ ) . '/includes/StreamFile.php' );
$perms = User::getGroupPermissions( array( '*' ) );
// See if this is a public Wiki (no protections)
if ( $wgImgAuthPublicTest && in_array( 'read', $perms, true ) )
wfForbidden('img-auth-accessdenied','img-auth-public');
// Extract path and image information
if( !isset( $_SERVER['PATH_INFO'] ) )
wfForbidden('img-auth-accessdenied','img-auth-nopathinfo');
$path = $_SERVER['PATH_INFO'];
$filename = realpath( $wgUploadDirectory . $_SERVER['PATH_INFO'] );
$realUpload = realpath( $wgUploadDirectory );
// Basic directory traversal check
if( substr( $filename, 0, strlen( $realUpload ) ) != $realUpload )
wfForbidden('img-auth-accessdenied','img-auth-notindir');
// Extract the file name and chop off the size specifier
// (e.g. 120px-Foo.png => Foo.png)
$name = wfBaseName( $path );
if( preg_match( '!\d+px-(.*)!i', $name, $m ) )
$name = $m[1];
// Check to see if the file exists
if( !file_exists( $filename ) )
wfForbidden('img-auth-accessdenied','img-auth-nofile',htmlspecialchars($filename));
// Check to see if tried to access a directory
if( is_dir( $filename ) )
wfForbidden('img-auth-accessdenied','img-auth-isdir',htmlspecialchars($filename));
$title = Title::makeTitleSafe( NS_FILE, $name );
// See if could create the title object
if( !$title instanceof Title )
wfForbidden('img-auth-accessdenied','img-auth-badtitle',htmlspecialchars($name));
// Run hook
if (!wfRunHooks( 'ImgAuthBeforeStream', array( &$title, &$path, &$name, &$result ) ) )
call_user_func_array('wfForbidden',merge_array(array($result[0],$result[1]),array_slice($result,2)));
// Check user authorization for this title
// UserCanRead Checks Whitelist too
if( !$title->userCanRead() )
wfForbidden('img-auth-accessdenied','img-auth-noread',htmlspecialchars($name));
// Stream the requested file
wfDebugLog( 'img_auth', "Streaming `".htmlspecialchars($filename)."`." );
wfStreamFile( $filename, array( 'Cache-Control: private', 'Vary: Cookie' ) );
wfLogProfilingData();
/**
* Issue a standard HTTP 403 Forbidden header ($msg1-a message index, not a message) and an
* error message ($msg2, also a message index), (both required) then end the script
* subsequent arguments to $msg2 will be passed as parameters only for replacing in $msg2
*/
function wfForbidden($msg1,$msg2) {
global $wgImgAuthDetails;
$args = func_get_args();
array_shift( $args );
array_shift( $args );
$MsgHdr = wfMsgHTML($msg1);
$detailMsg = call_user_func_array('wfMsgHTML',array_merge(array($wgImgAuthDetails ? $msg2 : 'badaccess-group0'),$args));
wfDebugLog('img_auth', "wfForbidden Hdr:".wfMsgExt( $msg1, array('language' => 'en'))." Msg: ".
call_user_func_array('wfMsgExt',array_merge( array($msg2, array('language' => 'en')),$args)));
header( 'HTTP/1.0 403 Forbidden' );
header( 'Cache-Control: no-cache' );
header( 'Content-Type: text/html; charset=utf-8' );
echo <<<ENDS
<html>
<body>
<h1>$MsgHdr</h1>
<p>$detailMsg</p>
</body>
</html>
ENDS;
wfLogProfilingData();
exit();
}