paypal

<?php/* Script de récupération et de vérification des données IPN de Paypal
        Avi here:  https://cms.paypal.com/cms_content/US/en_US/files/developer/IPN_PHP_41.txt */

// read the post from PayPal system and add 'cmd'
$req = 'cmd=_notify-validate';

foreach ($_POST as $cle => $valeur)
{
    $valeur = urlencode(stripslashes($valeur));
    $req .= "&$cle=$valeur";
}

// post back to PayPal system to validate
$header .= "POST /cgi-bin/webscr HTTP/1.0\r\n";
$header .= "Content-Type: application/x-www-form-urlencoded\r\n";
$header .= "Content-Length: " . strlen($req) . "\r\n\r\n";
$fp = fsockopen ('ssl://www.paypal.com', 443, $errno, $errstr, 30);// Connect via SSL.

// assign posted variables to local variables
$item_name = $_POST['item_name'];
$item_number = $_POST['item_number'];
$payment_status = $_POST['payment_status'];
$payment_amount = $_POST['mc_gross'];
$payment_currency = $_POST['mc_currency'];
$txn_id = $_POST['txn_id'];
$receiver_email = $_POST['receiver_email'];
$payer_email = $_POST['payer_email'];

if (!$fp) // If we cannot connect to paypal, we display an error
{
    echo "Error, cannot connect to paypal, IPN datas haven't been reposted";
}
else
{
    fputs ($fp, $header . $req);// fputs=fwrite | We throw back $req via the previous connexion (called $fp)
    while (!feof($fp))// Until it's not done : $fp
    {
        $res = fgets ($fp, 1024);
        if (strcmp ($res, "VERIFIED") == 0)// If we find the word VERIFIED (if datas received match with data from transaction)
        {
            if ($payment_status=="Completed" AND $receiver_email=="adresse@domaine.com" AND $payment_amount==5 AND $payment_currency=="EUR")// If every parameters are good, we can process the order
            {
                // What to do after the order (update database,...)
            }
        }
        else if (strcmp ($res, "INVALID") == 0) // If we find the word INVALID (datas received != datas from transaction)
        {
            echo "Error with IPN datas";
        }
    }
fclose ($fp);
}
?>