(MFC) DKIM Signature using Windows Current User Certificate Store

This is a Windows-specific example to load a certificate from the Current User (registry-based) certificate store, and then use the certificate's associated private key for a DKIM signature.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkCert.h>
#include <CkPrivateKey.h>
#include <CkDkim.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    CkCert cert;

    // The LoadByCommonName method searches the Windows Local Machine and Current User 
    // registry-based certificate stores for a certificate having the common name specified. 
    // If found, the certificate is loaded and ready for use.
    bool success = cert.LoadByCommonName("My Certificate ABC");
    if (success != true) {
        strOut.append(cert.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // The certificate must have an associated private key installed, and it must be a
    // private key that has been marked "exportable" when it was originally installed.
    if (!cert.HasPrivateKey()) {
        strOut.append("This certificate does not have a private key available.");
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkPrivateKey *privKey = 0;

    privKey = cert.ExportPrivateKey();
    if (cert.get_LastMethodSuccess() == false) {
        strOut.append(cert.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkDkim dkim;

    // Load the private key into the DKIM object:
    success = dkim.LoadDkimPk(privKey->getPkcs8Pem(),"");
    if (success != true) {
        strOut.append(dkim.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // The private key has been loaded into the DKIM object.  See the other DKIM
    // examples for guidance on how to create a DKIM signature...

    delete privKey;


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }