Untitled

<?php
session_start();
if (isset($_SESSION['u'])){
?>
<html>
<body>
<h1>Welcome to admin panel</h1>
<h2>Please provide XML file to interpret command</h2>
<form method="POST">
<textarea name="t" rows="25" cols="40">
<?xml version="1.0" encoding="UTF-8"?>
<commands>
    <command>ping</command>
</commands>

</textarea>
<input type="submit" name="submit">
<?php
}else{

?>
<html>
<body>
<h1> Admin panel v.0.1 </h1>
<form method="POST">
<p>User: <input type="name" name="login"></p>
<p>Password: <input type="password" name="pass"></p>
<input type="submit" name="Submit">
</form>
<a href="register.php">Register</a>
</body>
</html>


<?php
}

if (isset($_POST['t'])){
    if (strlen($_POST['t']) > 100){
        echo "You naughty haxxxor";
        session_unset();
        header("refresh:5;url=https://google.com");

    }
    libxml_disable_entity_loader (false);
    $dom = new DOMDocument();
    $dom->loadXML($_POST['t'], LIBXML_NOENT | LIBXML_DTDLOAD);
    $creds = simplexml_import_dom($dom);
    #$sites = new SimpleXMLElement($_POST['t']);
echo '<pre>';
    foreach ($creds->command as $c){
        echo($c);
    }
    echo "\n Command not implemented";
}
 login.php