(Perl) 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".

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

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

$listenSslSocket = chilkat::CkSocket->new();

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

$cert = chilkat::CkCert->new();
# The 1st argument is the file path, the 2nd arg is the 
# PFX file's password:
$success = $cert->LoadPfxFile("chilkat.pfx","test");
if ($success != 1) {
    print $cert->lastErrorText() . "\r\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 != 1) {
    print $listenSslSocket->lastErrorText() . "\r\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 != 1) {
    print $listenSslSocket->lastErrorText() . "\r\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 Socket
$clientSock = $listenSslSocket->AcceptNextConnection($maxWaitMillisec);
if ($listenSslSocket->get_LastMethodSuccess() == 0) {
    print $listenSslSocket->lastErrorText() . "\r\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() != 1) {
    print $clientSock->lastErrorText() . "\r\n";
    exit;
}

print $receivedMsg . "\r\n";

# Send a "Hello Client! -EOM-" message:
$success = $clientSock->SendString("Hello Client! -EOM-");
if ($success != 1) {
    print $clientSock->lastErrorText() . "\r\n";
    exit;
}

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