Paypal IPN CURL returns "SSL connect error" - paypal

Question

I am trying to implement ipn in my system but shows error
SSL connect error
TLS version shows TLS 1.0
It is a client's system. I downloaded the code from paypal website. I am currently testing it.
but it throws error
<?php
ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);
session_start();
$ch = curl_init('https://www.howsmyssl.com/a/check');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$data = curl_exec($ch);
curl_close($ch);
$json = json_decode($data);
echo $json->tls_version;
file_put_contents('NAB/paypal-ipn.txt', var_export($_POST, true));
echo "ipn processing";
// STEP 1: read POST data
// Reading POSTed data directly from $_POST causes serialization issues with array data in the POST.
// Instead, read raw POST data from the input stream.
$raw_post_data = file_get_contents('php://input');
$raw_post_array = explode('&', $raw_post_data);
$myPost = array();
foreach ($raw_post_array as $keyval) {
$keyval = explode ('=', $keyval);
if (count($keyval) == 2)
$myPost[$keyval[0]] = urldecode($keyval[1]);
}
echo "<br>1";
// read the IPN message sent from PayPal and prepend 'cmd=_notify-validate'
$req = 'cmd=_notify-validate';
if (function_exists('get_magic_quotes_gpc')) {
$get_magic_quotes_exists = true;
}
echo "<br>2";
foreach ($myPost as $key => $value) {
if ($get_magic_quotes_exists == true && get_magic_quotes_gpc() == 1) {
$value = urlencode(stripslashes($value));
} else {
$value = urlencode($value);
}
$req .= "&$key=$value";
}
echo "<br>3";
// Step 2: POST IPN data back to PayPal to validate
$ch = curl_init('https://www.sandbox.paypal.com/cgi-bin/webscr');
//$ch = curl_init('https://www.paypal.com/cgi-bin/webscr');
curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $req);
curl_setopt($ch, CURLOPT_SSLVERSION, 6);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Connection: Close'));
// In wamp-like environments that do not come bundled with root authority certificates,
// please download 'cacert.pem' from "http://curl.haxx.se/docs/caextract.html" and set
// the directory path of the certificate as shown below:
// curl_setopt($ch, CURLOPT_CAINFO, dirname(__FILE__) . '/cacert.pem');
echo "<br>3";
if ( !($res = curl_exec($ch)) ) {
error_log("Got " . curl_error($ch) . " when processing IPN data");
echo curl_error($ch);
curl_close($ch);
//exit;
}

Answer 1

If 'howsmyssl' is reporting that the systems supports only TLS v 1.0, it is likely that an upgrade is necessary to support TLS v 1.2. The curl_setopt($ch, CURLOPT_SSLVERSION, 6); is requesting TLS v 1.2 (see list in PHP Curl (with NSS) is probably using SSLv3 insted of TLS when connecting to https).
Also, as of June 30,2017, PayPal will be requiring TLS v 1.2 (see https://www.paypal-knowledge.com/infocenter/index?page=content&widgetview=true&id=FAQ1914&viewlocale=en_US and Php curl set ssl version).
You may be able to test your integration using TLS v 1.0 (until 6/30/2017) by changing to curl_setopt($ch, CURLOPT_SSLVERSION, 4);.

Answer 2

I had a similar problem problem when implementing the paypal ipn listener code. The script would stop executing where step 2 starts in the code you've provided. I solved it by downloading cacert.pem from http://curl.haxx.se/docs/caextract.html. Then I copied the downloaded file to the same folder as paypalipnlistener.php and then uncommented the following code in paypalipnlistener.php // curl_setopt($ch, CURLOPT_CAINFO, dirname(__FILE__) . '/cacert.pem'); to curl_setopt($ch, CURLOPT_CAINFO, dirname(__FILE__) . '/cacert.pem'); and the script executed successfully.