phpの認証クラス

/*
*       ，     
*/
class Suf_For3rd{
    private static $strBefore = '     ';


    public static function check($timestamp, $sign){

        $timenow = time();
        if(        ){

        }

        $timePart = $timestamp ; （         ）
        $originStr = self::$strBefore+...(          )
        $signLocal = md5($originStr);
        if($signLocal != $sign){
            //      
            return false;
        }

        return true;
    }
}