(Chilkat2-Python) Examine Client Certificates for an Accepted TLS Connection

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

Chilkat2 Python Downloads install with pip pip3 install chilkat2 or download... Python Module for Windows, Linux, Alpine Linux, MacOS, Solaris

import sys
import chilkat2

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

listenSslSocket = chilkat2.Socket()

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

cert = chilkat2.Cert()
success = cert.LoadPfxFile("qa_data/serverCert/myServerCert.pfx","pfx_password")
if (success != True):
    print(cert.LastErrorText)
    sys.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 != True):
    print(listenSslSocket.LastErrorText)
    sys.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)
    sys.exit()

# Accept the next incoming connection.
maxWaitMillisec = 20000
# clientSock is a CkSocket
clientSock = listenSslSocket.AcceptNextConnection(maxWaitMillisec)
if (listenSslSocket.LastMethodSuccess == False):
    print(listenSslSocket.LastErrorText)
    sys.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.NumReceivedClientCerts
print("numClientCerts = " + str(numClientCerts))

i = 0
while i < numClientCerts :
    # clientCert is a CkCert
    clientCert = clientSock.GetReceivedClientCert(i)
    print(clientCert.SubjectDN)

    i = i + 1

# Close the connection with the client
success = clientSock.Close(1000)