How to use X509Certificate2 as the credentials for a SharePointService request

Question

I have a MOSS 2007 farm that requires a client certificate to access. I have written several methods that use the built in SharePoint services to retrieve data from the site. However, outside of my local test environment everything requires a client cert to access the services.

My method for retrieving the cert is:

private static X509Certificate2 GetCertCreds()
{
     X509Store store = new X509Store(StoreName.My, StoreLocation.LocalMachine);
     try
     {
         store.Open(OpenFlags.ReadOnly);
                X509Certificate2Collection certs = store.Certificates.Find(X509FindType.FindBySubjectKeyIdentifier, "SiteIdentityCertificateSerialNumber", true);

         Assert.IsNotNull(certs);

         return certs[0];
     }
     finally
     {
          store.Close();
     }
}

Then in use I have to have something LIKE:

using (ListsServiceProxy.Lists service = new ListsServiceProxy.Lists())
{
    service.Crendentials = GetCredentials();
    XmlNode idResultsNode = service.GetListItems(documentLibraryName, null, queryNode, viewNode, "1", optionNode, null);
}

This is not compiling because of the type mismatch. Am I going about this the wrong way? If not is there a way to use the certificate as the services credentials? I think in end what I'm trying to do is convert an X509Certificate2 to ICredentials. Any help or advice would be greatly appreciated.

Answer 1

It turns out I had it all wrong. To correctly do this I replaced:

service.Credentials = GetCertCreds()

with

service.ClientCertificates.Add(GetCretCreds());

Adding the certificate into the service's client certificates collection is all that needed to happen.