Advertise Acceptable Client CA Names for Mutual TLS

See more Socket/SSL/TLS Examples

Demonstrates Socket.AddSslAcceptableClientCaDn, which adds a certificate-authority distinguished name to the list a TLS server advertises when requesting a client certificate for mutual TLS.

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

Dim success As Long
success = 0

Dim socket As New ChilkatSocket

'  For mutual TLS, advertise the acceptable client-certificate CA distinguished names BEFORE
'  initializing server-side TLS.  Call once for each acceptable CA distinguished name.
success = socket.AddSslAcceptableClientCaDn("CN=Example Root CA, O=Example, C=US")
If (success = 0) Then
    Debug.Print socket.LastErrorText
    Exit Sub
End If

success = socket.AddSslAcceptableClientCaDn("CN=Example Intermediate CA, O=Example, C=US")
If (success = 0) Then
    Debug.Print socket.LastErrorText
    Exit Sub
End If

'  The file path is relative to the application's current working directory.  An absolute path
'  may also be used.  Supply the path appropriate to your own environment.
'  The PFX password should come from a secure source rather than being hard-coded.
Dim pfxPassword As String
pfxPassword = "myPfxPassword"
Dim cert As New ChilkatCert
success = cert.LoadPfxFile("qa_data/server.pfx",pfxPassword)
If (success = 0) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

'  Initialize server-side TLS.  The server will now request a client certificate and advertise the
'  acceptable CA distinguished names added above.
success = socket.InitSslServer(cert)
If (success = 0) Then
    Debug.Print socket.LastErrorText
    Exit Sub
End If

Debug.Print "Server-side TLS configured to request client certificates."