/**
* Verify IPN by sending it back to PayPal for confirmation
*/
function ipn_postback($mode = 'IPN', $pdtTX = '')
{
$postdata = '';
$postback = '';
$postback_array = array();
// build postback string
if ($mode == 'PDT') {
if ($pdtTX == '') {
return FALSE;
}
// TX value not supplied, therefore PDT is disabled on merchant's PayPal profile.
ipn_debug_email('PDT PROCESSING INITIATED.' . "\n" . 'Preparing to verify transaction via PDT.' . "\n\n" . 'The TX token for verification is: ' . print_r($_GET, TRUE));
$postback .= "cmd=_notify-synch";
$postback .= "&tx=" . $_GET['tx'];
$postback .= "&at=" . trim(MODULE_PAYMENT_PAYPAL_PDTTOKEN);
$postback .= "&";
$postback_array['cmd'] = "_notify-sync";
$postback_array['tx'] = $_GET['tx'];
$postback_array['at'] = substr(MODULE_PAYMENT_PAYPAL_PDTTOKEN, 0, 5) . '**********' . substr(MODULE_PAYMENT_PAYPAL_PDTTOKEN, -5);
} elseif ($mode == 'IPN') {
$postback .= "cmd=_notify-validate";
$postback .= "&";
$postback_array['cmd'] = "_notify-validate";
}
foreach ($_POST as $key => $value) {
$postdata .= $key . "=" . urlencode(stripslashes($value)) . "&";
$postback .= $key . "=" . urlencode(stripslashes($value)) . "&";
$postback_array[$key] = $value;
}
if (substr($postdata, -2) == '=&') {
ipn_debug_email('IPN NOTICE :: No POST data to process -- Bad IPN data');
return $postdata;
}
$postback = rtrim($postback, '&');
$postdata = rtrim($postdata, '&');
$postdata_array = $_POST;
ksort($postdata_array);
if ($mode == 'IPN') {
ipn_debug_email('IPN INFO - POST VARS received (sorted):' . "\n" . stripslashes(urldecode(print_r($postdata_array, true))));
if (sizeof($postdata_array) == 0) {
die('Nothing to process. Please return to home page.');
}
}
// send received data back to PayPal for validation
$scheme = 'http://';
// Parse url
$web = parse_url($scheme . (defined('MODULE_PAYMENT_PAYPAL_HANDLER') ? MODULE_PAYMENT_PAYPAL_HANDLER : 'www.paypal.com/cgi-bin/webscr'));
if (isset($_POST['test_ipn']) && $_POST['test_ipn'] == 1) {
$web = parse_url($scheme . 'www.sandbox.paypal.com/cgi-bin/webscr');
}
// Set the port number
if ($web['scheme'] == "https") {
$web['port'] = "443";
$ssl = "ssl://";
} else {
$web['port'] = "80";
$ssl = "";
}
$result = '';
if (function_exists('curl_init')) {
$result = doPayPalIPNCurlPostback($web, $postback, $postback_array, $mode);
}
if ($mode == 'PDT') {
$info = $result['info'];
$result = $result['status'];
}
// DEBUG ONLY: ipn_debug_email('After CURL: $result='.$result);
if (!in_array(trim($result), array('VERIFIED', 'SUCCESS', 'INVALID', 'FAIL'))) {
ipn_debug_email('IPN NOTICE: Could not get usable response via CURL. Trying fsockopen() as fallback.' . ($result != '' ? ' [' . $result . ']' : ''));
$result = doPayPalIPNFsockopenPostback($web, $postback, $postback_array, $ssl, $mode);
if ($mode == 'PDT') {
$info = $result['info'];
$result = $result['status'];
}
}
return $mode == 'PDT' ? array('status' => $result, 'info' => $info) : trim($result);
}
}
if (isset($_POST['test_ipn']) && $_POST['test_ipn'] == 1) {
$web = parse_url($scheme . 'www.sandbox.paypal.com/cgi-bin/webscr');
}
//Set the port number
if ($web['scheme'] == "https") {
$web['port'] = "443";
$web['protocol'] = "ssl://";
} else {
$web['port'] = "80";
$web['protocol'] = "";
}
$result = '';
$data = '';
if (function_exists('curl_init')) {
$result = doPayPalIPNCurlPostback($web, $postback, $verboseMode, $headerMode);
if (in_array($result, array('VERIFIED', 'SUCCESS', 'INVALID'))) {
echo nl2br('IPN TESTING - Response Received via CURL -- <strong>COMMUNICATIONS OKAY</strong>' . "\n<!--" . $data . '-->');
$defaultMethod = 'CURL';
$altMethod = 'FSOCKOPEN';
}
} else {
echo nl2br('CURL not available. Will attempt to connect using fsockopen() instead.' . "\n");
}
if (!in_array($result, array('VERIFIED', 'SUCCESS', 'INVALID')) || $testBoth === TRUE) {
$result = doPayPalIPNFsockopenPostback($web, $postback);
echo nl2br('IPN TESTING - Confirmation/Validation response with fsockopen(): <strong>' . $result . "</strong>\n<!--" . $info . '-->');
if ($defaultMethod == '' && $result != 'FAILED') {
$defaultMethod = 'FSOCKOPEN';
$altMethod = 'CURL';
}