keygen.php

<?php

/*
Objetivo criar uma chave serial para cada dominio. O script pega a chave gerada e compara com o $_SERVER['HTTP_HOST']
*/

//link do demo do gen: http://onestepcheckout.com.br/LojaModelo/keygen/

//linha para ser add nas paginas que serao bloqueadas

/*
<?=(unserialize(rtrim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, md5(base64_decode('b25lc3RlcGNoZWNrb3V0NDA=')), base64_decode(strtr(Mage::getStoreConfig('onepagecheckout/general/keygen'), '-_,', '+/=')), MCRYPT_MODE_CBC, md5(md5(base64_decode('b25lc3RlcGNoZWNrb3V0NDA=')))), "\0")) == $_SERVER['HTTP_HOST'] ? "" : base64_decode("PGRpdiBjbGFzcz0nZXJyb2tleScgc3R5bGU9J3dpZHRoOiAxMDAlOyBsaW5lLWhlaWdodDogMjVweDsgYmFja2dyb3VuZC1jb2xvcjogI0ZGNjI4MjsgY29sb3I6ICNmZmY7IHRleHQtYWxpZ246IGNlbnRlcjsgcGFkZGluZzogM3B4OyBtYXJnaW4tYm90dG9tOiAxNXB4OyBmb250LXdlaWdodDogYm9sZDsnPlBvciBmYXZvciwgdmVyaWZpcXVlIG8gc2VyaWFsIGRpZ2l0YWRvIG5hIGFkbWluaXN0cmEmY2NlZGlsOyZhdGlsZGU7byBkbyBtJm9hY3V0ZTtkdWxvITwvZGl2Pg==") )?>
*/




define('SALT', 'frasepassedosalt'); //com isso da para se ter um key para cada versao, bastando trocar o salt na proxima versao

function encrypt ($stringArray, $key = SALT) {
 $s = strtr(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, md5($key), serialize($stringArray), MCRYPT_MODE_CBC, md5(md5($key)))), '+/=', '-_,');
 return $s;
}

function decrypt ($stringArray, $key = SALT) {
 $s = unserialize(rtrim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, md5($key), base64_decode(strtr($stringArray, '-_,', '+/=')), MCRYPT_MODE_CBC, md5(md5($key))), "\0"));
 return $s;
}
?>

<script type="text/javascript" src="http://davidwalsh.name/demo/mootools.1.2.3.js"></script>
<script type="text/javascript" src="http://davidwalsh.name/demo/ZeroClipboard.js"></script>



<script type="text/javascript">
window.addEvent("load",function() {

	setTimeout(function() {
		//set path
		ZeroClipboard.setMoviePath('http://davidwalsh.name/dw-content/ZeroClipboard.swf');
		//create client
		var clip = new ZeroClipboard.Client();
		//event
		clip.addEventListener('mousedown',function() {
			clip.setText(document.getElementById('serial').value);
		});
		clip.addEventListener('complete',function(client,text) {
			alert('serial copiado para seu clipboard: ' + text);
		});
		//glue it to the button
		clip.glue('copy');
	}, 2000);

});

</script>

<?php

if( isset($_POST['dominio']) ){

  $_POST['dominio'] = str_replace("http://", "", $_POST['dominio']);
  $_POST['dominio'] = str_replace("https://", "", $_POST['dominio']);

  $_POST['dominio'] = preg_replace('/^(www\.)/i', '', $_POST['dominio']);



  $f=fopen("dominios.txt","a+",0);
  $linha= "(".encrypt( $_POST['dominio'] )."):".$_POST['dominio']."\n";
  fwrite($f,$linha,strlen($linha));
  fclose($f);

}
?>

<center>
<h1>Gere seu serial do OSC PRO 4.0</h1>
<form method="post" name="Form1">
    Insire o dominio: <strong>www.</strong><input type="text" name="dominio" value="<?=$_POST['dominio']?>"/>
    <br />
    <input type="submit" value="Gerar Serial" />
</form>



<?

if (isset( $_POST['dominio'] ) ){
    echo "<br />";
    echo "<br />";

    $encryptedmessage = encrypt( $_POST['dominio'] );
    echo "<form method='post' name='Form2'>";
    echo "Serial Number: <br /><input type='text' id='serial' value='".$encryptedmessage."'  onclick='this.select(); ' style='width: 450px; padding: 10px; padding-left: 20px; padding-right: 20px; text-align: center;'>";
    echo "</form>";
?>

	<div style="position:relative; height: 25px; line-height: normal; cursor: pointer">
		<div href="javascript:;" id="copy" style="display:block; cursor: pointer">Copy to Clipboard</div>
	</div>
		<input type="button" id="copy" name="copy" value="Copy to Clipboard" style="margin-top:-10px; height: 25px; background: #CC0033; display: none" />


<?

    echo "<br />";
    echo "<br />";
    echo "Desbloqueio feito para o dominio: <br /><h1><strong>".decrypt($encryptedmessage)."</strong></h1>";
}

?>
</center>

ola eu vi como gerar o serial mais como vou fazer a verificação quando vou usar o seu script da erro
Fatal error: Class 'Mage' not found in /home/u850121487/public_html/verifica.php on line 1