(DataFlex) 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.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    Handle hoListenSslSocket
    Variant vCert
    Handle hoCert
    Boolean iSuccess
    Integer iMyPort
    Integer iBackLog
    Integer iMaxWaitMillisec
    Variant vClientSock
    Handle hoClientSock
    Integer iNumClientCerts
    Integer i
    Variant vClientCert
    Handle hoClientCert
    String sTemp1
    Boolean bTemp1

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

    Get Create (RefClass(cComChilkatSocket)) To hoListenSslSocket
    If (Not(IsComObjectCreated(hoListenSslSocket))) Begin
        Send CreateComObject of hoListenSslSocket
    End

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

    Get Create (RefClass(cComChilkatCert)) To hoCert
    If (Not(IsComObjectCreated(hoCert))) Begin
        Send CreateComObject of hoCert
    End
    Get ComLoadPfxFile Of hoCert "qa_data/serverCert/myServerCert.pfx" "pfx_password" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoCert To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // 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.
    Get ComAddSslAcceptableClientCaDn Of hoListenSslSocket "C=SE, O=AddTrust AB, OU=AddTrust External TTP Network, CN=AddTrust External CA Root" To iSuccess
    Get ComAddSslAcceptableClientCaDn Of hoListenSslSocket "O=Digital Signature Trust Co., CN=DST Root CA X3" To iSuccess

    // Initialize with our server's TLS certificate.
    Get pvComObject of hoCert to vCert
    Get ComInitSslServer Of hoListenSslSocket vCert To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoListenSslSocket To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Bind and listen on a port:
    Move 8123 To iMyPort
    // Allow for a max of 5 queued connect requests.
    Move 5 To iBackLog
    Get ComBindAndListen Of hoListenSslSocket iMyPort iBackLog To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoListenSslSocket To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Accept the next incoming connection.
    Move 20000 To iMaxWaitMillisec
    Get ComAcceptNextConnection Of hoListenSslSocket iMaxWaitMillisec To vClientSock
    If (IsComObject(vClientSock)) Begin
        Get Create (RefClass(cComChilkatSocket)) To hoClientSock
        Set pvComObject Of hoClientSock To vClientSock
    End
    Get ComLastMethodSuccess Of hoListenSslSocket To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoListenSslSocket To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // 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.
    Get ComNumReceivedClientCerts Of hoClientSock To iNumClientCerts
    Showln "numClientCerts = " iNumClientCerts

    Move 0 To i
    While (i < iNumClientCerts)
        Get ComGetReceivedClientCert Of hoClientSock i To vClientCert
        If (IsComObject(vClientCert)) Begin
            Get Create (RefClass(cComChilkatCert)) To hoClientCert
            Set pvComObject Of hoClientCert To vClientCert
        End
        Get ComSubjectDN Of hoClientCert To sTemp1
        Showln sTemp1
        Send Destroy of hoClientCert
        Move i + 1 To i
    Loop

    // Close the connection with the client
    Get ComClose Of hoClientSock 1000 To iSuccess

    Send Destroy of hoClientSock


End_Procedure