private ClientCertificateValidationResult ValidateCertificate(IDictionary <string, object> owinEnvironment) { if (owinEnvironment.ContainsKey(_owinClientCertKey)) { X509Certificate2 clientCert = Context.Get <X509Certificate2>(_owinClientCertKey); return(_clientCertificateValidator.Validate(clientCert)); } ClientCertificateValidationResult invalid = new ClientCertificateValidationResult(false); invalid.AddValidationException("There's no client certificate attached to the request."); return(invalid); }