CkPython Requires Chilkat v11.0.0+

Accept TLS Connection with Client Authentication

See more Socket/SSL/TLS Examples

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". CkPython

import sys
import chilkat

success = False

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

listenSslSocket = chilkat.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 = chilkat.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 == False):
    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")

#  Use the certificate:
success = listenSslSocket.InitSslServer(cert)
if (success == False):
    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 == False):
    print(listenSslSocket.lastErrorText())
    sys.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 
#  AcceptNext can hang indefinitely during the SSL handshake process. 
#  Make sure these properties are set to appropriate values before calling AcceptNext.

#  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 = chilkat.CkSocket()
success = listenSslSocket.AcceptNext(maxWaitMillisec,clientSock)
if (success == False):
    print(listenSslSocket.lastErrorText())
    sys.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() == False):
    print(clientSock.lastErrorText())
    sys.exit()

print(receivedMsg)

#  Send a "Hello Client! -EOM-" message:
success = clientSock.SendString("Hello Client! -EOM-")
if (success == False):
    print(clientSock.lastErrorText())
    sys.exit()

#  Close the connection with the client
#  Wait a max of 20 seconds (20000 millsec)
success = clientSock.Close(20000)