(PHP Extension) Accept TLS Connection with Client Authentication

Demonstrates how to accept a TLS connection requiring client authentication. This is the case where the TLS client sends a certificate. It is also known as "Two-Way SSL".

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<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

// 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.
// Note: This is the server's certificate.

$cert = new CkCert();
// The 1st argument is the file path, the 2nd arg is the 
// PFX file's password:
$success = $cert->LoadPfxFile('chilkat.pfx','test');
if ($success != true) {
    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');

// Use the certificate:
$success = $listenSslSocket->InitSslServer($cert);
if ($success != true) {
    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 != true) {
    print $listenSslSocket->lastErrorText() . "\n";
    exit;
}

// If accepting an SSL/TLS connection, the SSL handshake is part of the connection
// establishment process. This involves a few back-and-forth messages between the 
// client and server to establish algorithms and a shared key to create the secure 
// channel. The sending and receiving of these messages are governed by the 
// MaxReadIdleMs and MaxSendIdleMs properties. If these properties are set to 0 
// (and this is the default unless changed by your application), then the 
// AcceptNextConnection can hang indefinitely during the SSL handshake process. 
// Make sure these properties are set to appropriate values before calling AcceptNextConnection.

// Set a 10 second max for waiting to read/write.  This is for the SSL/TLS handshake establishment.
$listenSslSocket->put_MaxReadIdleMs(10000);
$listenSslSocket->put_MaxSendIdleMs(10000);

// Accept a single client connection and establish the secure SSL/TLS channel:

$maxWaitMillisec = 20000;
// clientSock is a CkSocket
$clientSock = $listenSslSocket->AcceptNextConnection($maxWaitMillisec);
if ($listenSslSocket->get_LastMethodSuccess() == false) {
    print $listenSslSocket->lastErrorText() . "\n";
    exit;
}

// The client (in this example) is going to send a "Hello Server! -EOM-" 
// message.  Read it:
$receivedMsg = $clientSock->receiveUntilMatch('-EOM-');
if ($clientSock->get_LastMethodSuccess() != true) {
    print $clientSock->lastErrorText() . "\n";
    exit;
}

print $receivedMsg . "\n";

// Send a "Hello Client! -EOM-" message:
$success = $clientSock->SendString('Hello Client! -EOM-');
if ($success != true) {
    print $clientSock->lastErrorText() . "\n";
    exit;
}

// Close the connection with the client
// Wait a max of 20 seconds (20000 millsec)
$success = $clientSock->Close(20000);


?>