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PHP Extension

Examine Client Certificates for an Accepted TLS Connection

See more Socket/SSL/TLS Examples

Demonstrates how to access the client certificates for a TLS connection accepted by your application acting as the server.

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.

$listenSslSocket = new CkSocket();

// An SSL/TLS server needs a digital certificate.  This example loads it from a PFX file.
// This is the server's certificate.

$cert = new CkCert();
$success = $cert->LoadPfxFile('qa_data/serverCert/myServerCert.pfx','pfx_password');
if ($success == false) {
    print $cert->lastErrorText() . "\n";
    exit;
}

// To accept client client certificates in the TLS handshake,
// we must indicate a list of acceptable client certificate root CA DN's
// that are allowed.  (DN is an acronym for Distinguished Name.)
// Call AddSslAcceptableClientCaDn once for each acceptable CA DN.
// Here are a few examples so you can see the general format of a DN.
$listenSslSocket->AddSslAcceptableClientCaDn('C=SE, O=AddTrust AB, OU=AddTrust External TTP Network, CN=AddTrust External CA Root');
$listenSslSocket->AddSslAcceptableClientCaDn('O=Digital Signature Trust Co., CN=DST Root CA X3');

// Initialize with our server's TLS certificate.
$success = $listenSslSocket->InitSslServer($cert);
if ($success == false) {
    print $listenSslSocket->lastErrorText() . "\n";
    exit;
}

// Bind and listen on a port:
$myPort = 8123;
// Allow for a max of 5 queued connect requests.
$backLog = 5;
$success = $listenSslSocket->BindAndListen($myPort,$backLog);
if ($success == false) {
    print $listenSslSocket->lastErrorText() . "\n";
    exit;
}

// Accept the next incoming connection.
$maxWaitMillisec = 20000;

$clientSock = new CkSocket();
$success = $listenSslSocket->AcceptNext($maxWaitMillisec,$clientSock);
if ($success == false) {
    print $listenSslSocket->lastErrorText() . "\n";
    exit;
}

// Examine the client certs chain.  The 1st cert will be the client certificate, and
// the subsequent certs will be the certs in the chain of authentication.
$numClientCerts = $clientSock->get_NumReceivedClientCerts();
print 'numClientCerts = ' . $numClientCerts . "\n";

$clientCert = new CkCert();
$i = 0;
while ($i < $numClientCerts) {
    $clientSock->GetRcvdClientCert($i,$clientCert);
    print $clientCert->subjectDN() . "\n";
    $i = $i + 1;
}

// Close the connection with the client
$success = $clientSock->Close(1000);

?>