(MFC) 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 C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkCert.h>
#include <CkXml.h>
#include <CkStringBuilder.h>

void ChilkatSample(void)
    {
    CkString strOut;

    CkCert cert;

    bool success = cert.LoadFromFile("qa_data/certs/test_haswdt.cer");
    if (success != true) {
        strOut.append(cert.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    //  Get the CRL Distribution Points extension, which is at OID 2.5.29.31
    const char *extensionXmlStr = cert.getExtensionAsXml("2.5.29.31");
    if (cert.get_LastMethodSuccess() == false) {
        strOut.append("Certificate does not have the CDP extension.");
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkXml xml;
    xml.LoadXml(extensionXmlStr);

    //  See what we have..
    strOut.append(xml.getXml());
    strOut.append("\r\n");

    //  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...
    CkStringBuilder sbDistPoint;
    success = xml.GetChildContentSb("sequence|contextSpecific|contextSpecific|contextSpecific",sbDistPoint);
    if (success == true) {
        sbDistPoint.Decode("base64","utf-8");
        strOut.append("CRL Distribution Point:  ");
        strOut.append(sbDistPoint.getAsString());
        strOut.append("\r\n");
    }

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


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }