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PHP Extension

Use HTTPS Client Certificate from .cer and .key Files

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Demonstrates how to load a cert + private key from .cer and .key (base64) files and use it for mutual TLS authentication (client-side certificate).

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

$http = new CkHttp();

$cert = new CkCert();
$privKey = new CkPrivateKey();

// Load any type of certificate (.cer, .p7b, .pem, etc.) by calling LoadFromFile.
$success = $cert->LoadFromFile('qa_data/certs/sample_cert_a.cer');
if ($success != true) {
    print $cert->lastErrorText() . "\n";
    exit;
}

// Load the private key.
$bd = new CkBinData();
$success = $bd->LoadFile('qa_data/certs/sample_key_a.key');
$success = $privKey->LoadAnyFormat($bd,'privateKeyPasswordIfNecessary');
if ($success != true) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

// Associate the private key with the cert.
$success = $cert->SetPrivateKey($privKey);
if ($success != true) {
    print $cert->lastErrorText() . "\n";
    exit;
}

// Set the certificate to be used for mutual TLS authentication
// (i.e. sets the client-side certificate for two-way TLS authentication)
$success = $http->SetSslClientCert($cert);
if ($success != true) {
    print $http->lastErrorText() . "\n";
    exit;
}

// At this point, the HTTP object instance is setup with the client-side cert, and any SSL/TLS
// connection will automatically use it if the server demands a client-side cert.

?>