(DataFlex) Get Certificate CRL Distribution Points

Demonstrates how to get a certificate's CRL Distribution Points extension data (assuming it exists). In the vast majority of cases, there will be one CRL Distribution Point.

Note: This example requires Chilkat v9.5.0.76 or greater.

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

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoCert
    Boolean iSuccess
    String sExtensionXmlStr
    Handle hoXml
    Variant vSbDistPoint
    Handle hoSbDistPoint
    String sTemp1
    Boolean bTemp1

    Get Create (RefClass(cComChilkatCert)) To hoCert
    If (Not(IsComObjectCreated(hoCert))) Begin
        Send CreateComObject of hoCert
    End

    Get ComLoadFromFile Of hoCert "qa_data/certs/test_haswdt.cer" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoCert To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Get the CRL Distribution Points extension, which is at OID 2.5.29.31
    Get ComGetExtensionAsXml Of hoCert "2.5.29.31" To sExtensionXmlStr
    Get ComLastMethodSuccess Of hoCert To bTemp1
    If (bTemp1 = False) Begin
        Showln "Certificate does not have the CDP extension."
        Procedure_Return
    End

    Get Create (RefClass(cComChilkatXml)) To hoXml
    If (Not(IsComObjectCreated(hoXml))) Begin
        Send CreateComObject of hoXml
    End
    Get ComLoadXml Of hoXml sExtensionXmlStr To iSuccess

    // See what we have..
    Get ComGetXml Of hoXml To sTemp1
    Showln sTemp1

    // We should get XML like this:

    // <?xml version="1.0" encoding="utf-8" ?>
    // <sequence>
    //     <sequence>
    //         <contextSpecific tag="0" constructed="1">
    //             <contextSpecific tag="0" constructed="1">
    //                 <contextSpecific tag="6" constructed="0">aHR0cDovL2NybC5jb21vZG9jYS5jb20vQ09NT0RPUlNBQ2xpZW50QXV0aGVudGljYXRpb25hbmRTZWN1
    // cmVFbWFpbENBLmNybA==</contextSpecific>
    //             </contextSpecific>
    //         </contextSpecific>
    //     </sequence>
    // </sequence>
    // 

    // Assuming there is one CRL Distribution Point...
    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbDistPoint
    If (Not(IsComObjectCreated(hoSbDistPoint))) Begin
        Send CreateComObject of hoSbDistPoint
    End
    Get pvComObject of hoSbDistPoint to vSbDistPoint
    Get ComGetChildContentSb Of hoXml "sequence|contextSpecific|contextSpecific|contextSpecific" vSbDistPoint To iSuccess
    If (iSuccess = True) Begin
        Get ComDecode Of hoSbDistPoint "base64" "utf-8" To iSuccess
        Get ComGetAsString Of hoSbDistPoint To sTemp1
        Showln "CRL Distribution Point:  " sTemp1
    End

    // Sample output:
    // CRL Distribution Point:  http://crl.comodoca.com/COMODORSAClientAuthenticationandSecureEmailCA.crl


End_Procedure