public void TestCertificateExtraction_01()
        {
            XmlDocument doc = new XmlDocument();

            doc.PreserveWhitespace = true;
            doc.Load(@"Saml20\Protocol\MetadataDocs\metadata-ADLER.xml");

            Saml20MetadataDocument metadata = new Saml20MetadataDocument(doc);
            List <KeyDescriptor>   keys     = metadata.Keys;

            Assert.That(keys[0].use == KeyTypes.signing);
            Assert.That(keys[1].use == KeyTypes.encryption);

            Assert.That(metadata.GetKeys(KeyTypes.signing).Count == 1);
            Assert.That(metadata.GetKeys(KeyTypes.encryption).Count == 1);

            // The two certs in the metadata document happen to be identical, and are also
            // used for signing the entire document.
            // Extract the certificate and verify the document.

            KeyInfo keyinfo = (KeyInfo)keys[0].KeyInfo;

            Assert.That(XmlSignatureUtils.CheckSignature(doc, keyinfo));
            Assert.AreEqual("ADLER_SAML20_ID", metadata.EntityId);
        }
示例#2
0
            public void CanExtractCertificates()
            {
                // Arrange
                var doc = new XmlDocument {
                    PreserveWhitespace = true
                };

                doc.Load(@"Protocol\MetadataDocs\metadata-ADLER.xml");

                // Act
                var metadata = new Saml20MetadataDocument(doc);
                var certificateCheckResult = XmlSignatureUtils.CheckSignature(doc, (KeyInfo)metadata.Keys[0].KeyInfo);

                // Assert
                Assert.That(metadata.GetKeys(KeyTypes.Signing).Count == 1);
                Assert.That(metadata.GetKeys(KeyTypes.Encryption).Count == 1);
                Assert.That(metadata.Keys[0].Use == KeyTypes.Signing);
                Assert.That(metadata.Keys[1].Use == KeyTypes.Encryption);

                // The two certs in the metadata document happen to be identical, and are also
                // used for signing the entire document.
                // Extract the certificate and verify the document.
                Assert.That(certificateCheckResult);
                Assert.AreEqual("ADLER_SAML20_ID", metadata.EntityId);
            }
            public void CanExtractCertificatesOnStream()
            {
                Saml20MetadataDocument metadata;
                // Arrange
                using (var ms = new MemoryStream()) {
                    using (var reader = File.OpenText(@"Protocol\MetadataDocs\metadata-ADLER.xml")) {
                        reader.BaseStream.CopyTo(ms);
                        reader.Close();
                    }
                    ms.Seek(0, SeekOrigin.Begin);
                    metadata = new Saml20MetadataDocument(ms, null);
                }

                // Assert
                Assert.That(metadata.GetKeys(KeyTypes.Signing).Count == 1);
                Assert.That(metadata.GetKeys(KeyTypes.Encryption).Count == 1);
                Assert.That(metadata.Keys[0].Use == KeyTypes.Signing);
                Assert.That(metadata.Keys[1].Use == KeyTypes.Encryption);

                Assert.AreEqual("ADLER_SAML20_ID", metadata.EntityId);
            }
            public void CanExtractCertificates()
            {
                // Arrange
                var doc = new XmlDocument { PreserveWhitespace = true };
                doc.Load(@"Protocol\MetadataDocs\metadata-ADLER.xml");

                // Act
                var metadata = new Saml20MetadataDocument(doc);
                var certificateCheckResult = XmlSignatureUtils.CheckSignature(doc, (KeyInfo)metadata.Keys[0].KeyInfo);

                // Assert
                Assert.That(metadata.GetKeys(KeyTypes.Signing).Count == 1);
                Assert.That(metadata.GetKeys(KeyTypes.Encryption).Count == 1);
                Assert.That(metadata.Keys[0].Use == KeyTypes.Signing);
                Assert.That(metadata.Keys[1].Use == KeyTypes.Encryption);

                // The two certs in the metadata document happen to be identical, and are also
                // used for signing the entire document.
                // Extract the certificate and verify the document.
                Assert.That(certificateCheckResult);
                Assert.AreEqual("ADLER_SAML20_ID", metadata.EntityId);
            }
            public void CanExtractCertificatesOnStream()
            {
                Saml20MetadataDocument metadata;

                // Arrange
                using (var ms = new MemoryStream()) {
                    using (var reader = File.OpenText(@"Protocol\MetadataDocs\metadata-ADLER.xml")) {
                        reader.BaseStream.CopyTo(ms);
                        reader.Close();
                    }
                    ms.Seek(0, SeekOrigin.Begin);
                    metadata = new Saml20MetadataDocument(ms, null);
                }

                // Assert
                Assert.That(metadata.GetKeys(KeyTypes.Signing).Count == 1);
                Assert.That(metadata.GetKeys(KeyTypes.Encryption).Count == 1);
                Assert.That(metadata.Keys[0].Use == KeyTypes.Signing);
                Assert.That(metadata.Keys[1].Use == KeyTypes.Encryption);

                Assert.AreEqual("ADLER_SAML20_ID", metadata.EntityId);
            }
示例#6
0
        /// <summary>
        /// Checks the signature of a message received using the redirect binding using the keys found in the
        /// metadata of the federation partner that sent the request.
        /// </summary>
        protected static bool CheckRedirectSignature(HttpRedirectBindingParser parser, Saml20MetadataDocument metadata)
        {
            List <KeyDescriptor> keys = metadata.GetKeys(KeyTypes.signing);

            // Go through the list of signing keys (usually only one) and use it to verify the REDIRECT request.
            foreach (KeyDescriptor key in keys)
            {
                KeyInfo keyinfo = (KeyInfo)key.KeyInfo;
                foreach (KeyInfoClause keyInfoClause in keyinfo)
                {
                    AsymmetricAlgorithm signatureKey = XmlSignatureUtils.ExtractKey(keyInfoClause);
                    if (signatureKey != null && parser.CheckSignature(signatureKey))
                    {
                        return(true);
                    }
                }
            }
            return(false);
        }
示例#7
0
        private void HandleRequest(HttpContext context)
        {
            Trace.TraceMethodCalled(GetType(), "HandleRequest()");

            //Fetch config object
            SAML20FederationConfig config = SAML20FederationConfig.GetConfig();

            LogoutRequest logoutRequest = null;
            IDPEndPoint endpoint = null;
            string message = string.Empty;

            //Build the response object
            var response = new Saml20LogoutResponse();
            response.Issuer = config.ServiceProvider.ID;
            response.StatusCode = Saml20Constants.StatusCodes.Success; // Default success. Is overwritten if something fails.
            
            if(context.Request.RequestType == "GET") // HTTP Redirect binding
            {
                HttpRedirectBindingParser parser = new HttpRedirectBindingParser(context.Request.Url);
                AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST,
                                      string.Format("Binding: redirect, Signature algorithm: {0}  Signature:  {1}, Message: {2}", parser.SignatureAlgorithm, parser.Signature, parser.Message));

                if (!parser.IsSigned)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Signature not present, msg: " + parser.Message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                logoutRequest = parser.LogoutRequest;
                endpoint = config.FindEndPoint(logoutRequest.Issuer.Value);

                if (endpoint.metadata == null)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Cannot find metadata for IdP: " + logoutRequest.Issuer.Value);
                    // Not able to return a response as we do not know the IdP.
                    HandleError(context, "Cannot find metadata for IdP " + logoutRequest.Issuer.Value);
                    return;
                }

                Saml20MetadataDocument metadata = endpoint.metadata;

                if (!parser.VerifySignature(metadata.GetKeys(KeyTypes.signing)))
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Request has been denied. Invalid signature redirect-binding, msg: " + parser.Message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                message = parser.Message;
            }
            else if (context.Request.RequestType == "POST") // HTTP Post binding
            {
                HttpPostBindingParser parser = new HttpPostBindingParser(context);
                AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST,
                                      "Binding: POST, Message: " + parser.Message);

                if (!parser.IsSigned())
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Signature not present, msg: " + parser.Message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                logoutRequest = parser.LogoutRequest;
                endpoint = config.FindEndPoint(logoutRequest.Issuer.Value);
                if (endpoint.metadata == null)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Cannot find metadata for IdP");
                    // Not able to return a response as we do not know the IdP.
                    HandleError(context, "Cannot find metadata for IdP " + logoutRequest.Issuer.Value);
                    return;
                }

                Saml20MetadataDocument metadata = endpoint.metadata;

                // handle a logout-request
                if (!parser.CheckSignature(metadata.GetKeys(KeyTypes.signing)))
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Request has been denied. Invalid signature post-binding, msg: " + parser.Message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                message = parser.Message;
            }else
            {
                //Error: We don't support HEAD, PUT, CONNECT, TRACE, DELETE and OPTIONS
                // Not able to return a response as we do not understand the request.
                HandleError(context, Resources.UnsupportedRequestTypeFormat(context.Request.RequestType));
            }

            AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, message);
            
            // Check that idp in session and request matches.
            string idpRequest = logoutRequest.Issuer.Value;
            if (!context.Session.IsNewSession)
            {
                object idpSession = context.Session[IDPLoginSessionKey];
            
                if (idpSession != null && idpSession.ToString() != idpRequest)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, Resources.IdPMismatchBetweenRequestAndSessionFormat(idpSession, idpRequest), message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }
            }
            else
            {
                // All other status codes than Success results in the IdP throwing an error page. Therefore we return default Success even if we do not have a session.
                AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Session does not exist. Continues the redirect logout procedure with status code success." + idpRequest, message);
            }

            //  Only logout if request is valid and we are working on an existing Session.
            if (Saml20Constants.StatusCodes.Success == response.StatusCode && !context.Session.IsNewSession)
            {
                // Execute all actions that the service provider has configured
                DoLogout(context, true);
            }

            // Update the response object with informations that first is available when request has been parsed.
            IDPEndPointElement destination = DetermineEndpointConfiguration(SAMLBinding.REDIRECT, endpoint.SLOEndpoint, endpoint.metadata.SLOEndpoints());
            response.Destination = destination.Url;
            response.InResponseTo = logoutRequest.ID;

            //Respond using redirect binding
            if(destination.Binding == SAMLBinding.REDIRECT)
            {
                HttpRedirectBindingBuilder builder = new HttpRedirectBindingBuilder();
                builder.RelayState = context.Request.Params["RelayState"];
                builder.Response = response.GetXml().OuterXml;
                builder.signingKey = FederationConfig.GetConfig().SigningCertificate.GetCertificate().PrivateKey;
                string s = destination.Url + "?" + builder.ToQuery();
                context.Response.Redirect(s, true);
                return;
            }

            //Respond using post binding
            if (destination.Binding == SAMLBinding.POST)
            {
                HttpPostBindingBuilder builder = new HttpPostBindingBuilder(destination);
                builder.Action = SAMLAction.SAMLResponse;                                
                XmlDocument responseDocument = response.GetXml();
                XmlSignatureUtils.SignDocument(responseDocument, response.ID);
                builder.Response = responseDocument.OuterXml;
                builder.RelayState = context.Request.Params["RelayState"];
                builder.GetPage().ProcessRequest(context);
                return;
            }
        }
示例#8
0
        private void HandleSOAP(HttpContext context, Stream inputStream)
        {
            Trace.TraceMethodCalled(GetType(), "HandleSOAP");

            HttpArtifactBindingParser  parser  = new HttpArtifactBindingParser(inputStream);
            HttpArtifactBindingBuilder builder = new HttpArtifactBindingBuilder(context);

            SAML20FederationConfig config = SAML20FederationConfig.GetConfig();

            IDPEndPoint idp = RetrieveIDPConfiguration(parser.Issuer);
            var         shaHashingAlgorithm = SignatureProviderFactory.ValidateShaHashingAlgorithm(idp.ShaHashingAlgorithm);

            AuditLogging.IdpId = idp.Id;


            if (parser.IsArtifactResolve())
            {
                Trace.TraceData(TraceEventType.Information, Tracing.ArtifactResolveIn);

                if (!parser.CheckSamlMessageSignature(idp.metadata.Keys))
                {
                    HandleError(context, "Invalid Saml message signature");
                    AuditLogging.logEntry(Direction.UNDEFINED, Operation.ARTIFACTRESOLVE, "Signature could not be verified", parser.SamlMessage);
                }
                AuditLogging.AssertionId = parser.ArtifactResolve.ID;
                AuditLogging.logEntry(Direction.IN, Operation.ARTIFACTRESOLVE, "", parser.SamlMessage);
                builder.RespondToArtifactResolve(idp, parser.ArtifactResolve);
            }
            else if (parser.IsArtifactResponse())
            {
                Trace.TraceData(TraceEventType.Information, Tracing.ArtifactResponseIn);

                Status status = parser.ArtifactResponse.Status;
                if (status.StatusCode.Value != Saml20Constants.StatusCodes.Success)
                {
                    AuditLogging.logEntry(Direction.UNDEFINED, Operation.ARTIFACTRESOLVE, string.Format("Unexpected status code for artifact response: {0}, expected 'Success', msg: {1}", status.StatusCode.Value, parser.SamlMessage));
                    HandleError(context, status);
                    return;
                }

                if (parser.ArtifactResponse.Any.LocalName == LogoutRequest.ELEMENT_NAME)
                {
                    if (Trace.ShouldTrace(TraceEventType.Information))
                    {
                        Trace.TraceData(TraceEventType.Information, string.Format(Tracing.LogoutRequest, parser.ArtifactResponse.Any.OuterXml));
                    }

                    //Send logoutresponse via artifact
                    Saml20LogoutResponse response = new Saml20LogoutResponse();
                    response.Issuer = config.ServiceProvider.ID;
                    LogoutRequest req = Serialization.DeserializeFromXmlString <LogoutRequest>(parser.ArtifactResponse.Any.OuterXml);
                    response.StatusCode   = Saml20Constants.StatusCodes.Success;
                    response.InResponseTo = req.ID;
                    IDPEndPointElement destination =
                        DetermineEndpointConfiguration(SAMLBinding.REDIRECT, idp.SLOEndpoint, idp.metadata.SLOEndpoints());

                    builder.RedirectFromLogout(idp, destination, response);
                }
                else if (parser.ArtifactResponse.Any.LocalName == LogoutResponse.ELEMENT_NAME)
                {
                    DoLogout(context);
                }
                else
                {
                    AuditLogging.logEntry(Direction.UNDEFINED, Operation.ARTIFACTRESOLVE, string.Format("Unsupported payload message in ArtifactResponse: {0}, msg: {1}", parser.ArtifactResponse.Any.LocalName, parser.SamlMessage));
                    HandleError(context,
                                string.Format("Unsupported payload message in ArtifactResponse: {0}",
                                              parser.ArtifactResponse.Any.LocalName));
                }
            }
            else if (parser.IsLogoutReqest())
            {
                if (Trace.ShouldTrace(TraceEventType.Information))
                {
                    Trace.TraceData(TraceEventType.Information, string.Format(Tracing.LogoutRequest, parser.SamlMessage.OuterXml));
                }

                Saml20LogoutResponse response = new Saml20LogoutResponse();

                if (!parser.IsSigned())
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Signature not present in SOAP logout request, msg: " + parser.SamlMessage.OuterXml);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                if (idp.metadata == null)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Cannot find metadata for IdP: " + parser.Issuer);
                    // Not able to process the request as we do not know the IdP.
                    response.StatusCode = Saml20Constants.StatusCodes.NoAvailableIDP;
                }
                else
                {
                    Saml20MetadataDocument metadata = idp.metadata;

                    if (!parser.CheckSignature(metadata.GetKeys(KeyTypes.signing)))
                    {
                        AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Request has been denied. Invalid signature SOAP logout, msg: " + parser.SamlMessage.OuterXml);
                        response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                    }
                }

                if (parser.GetNameID() != null && !string.IsNullOrEmpty(parser.GetNameID().Value))
                {
                    DoSoapLogout(context, parser.GetNameID().Value);
                }
                else
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Request has been denied. No user ID was supplied in SOAP logout request, msg: " + parser.SamlMessage.OuterXml);
                    response.StatusCode = Saml20Constants.StatusCodes.NoAuthnContext;
                }

                LogoutRequest req = parser.LogoutRequest;

                //Build the response object
                response.Issuer       = config.ServiceProvider.ID;
                response.StatusCode   = Saml20Constants.StatusCodes.Success;
                response.InResponseTo = req.ID;
                XmlDocument doc = response.GetXml();
                var         signingCertificate = FederationConfig.GetConfig().SigningCertificate.GetCertificate();
                var         signatureProvider  = SignatureProviderFactory.CreateFromShaHashingAlgorithmName(shaHashingAlgorithm);
                signatureProvider.SignAssertion(doc, response.ID, signingCertificate);
                if (doc.FirstChild is XmlDeclaration)
                {
                    doc.RemoveChild(doc.FirstChild);
                }

                builder.SendResponseMessage(doc.OuterXml);
            }
            else
            {
                Status s = parser.GetStatus();
                if (s != null)
                {
                    HandleError(context, s);
                }
                else
                {
                    AuditLogging.logEntry(Direction.UNDEFINED, Operation.ARTIFACTRESOLVE, string.Format("Unsupported SamlMessage element: {0}, msg: {1}", parser.SamlMessageName, parser.SamlMessage));
                    HandleError(context, string.Format("Unsupported SamlMessage element: {0}", parser.SamlMessageName));
                }
            }
        }
        private void HandleRequest(HttpContext context)
        {
            Trace.TraceMethodCalled(GetType(), "HandleRequest()");

            //Fetch the endpoint configuration
            IDPEndPoint idpEndpoint = RetrieveIDPConfiguration(context.Session[IDPLoginSessionKey].ToString());

            IDPEndPointElement destination =
                DetermineEndpointConfiguration(SAMLBinding.REDIRECT, idpEndpoint.SLOEndpoint, idpEndpoint.metadata.SLOEndpoints());

            //Fetch config object
            SAML20FederationConfig config = ConfigurationReader.GetConfig <SAML20FederationConfig>();

            //Build the response object
            Saml20LogoutResponse response = new Saml20LogoutResponse();

            response.Issuer      = config.ServiceProvider.ID;
            response.Destination = destination.Url;
            response.StatusCode  = Saml20Constants.StatusCodes.Success;

            string message = string.Empty;

            if (context.Request.RequestType == "GET") // HTTP Redirect binding
            {
                HttpRedirectBindingParser parser = new HttpRedirectBindingParser(context.Request.Url);
                IDPEndPoint endpoint             = config.FindEndPoint(idpEndpoint.Id);

                if (endpoint.metadata == null)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Cannot find metadata for IdP");
                    HandleError(context, "Cannot find metadata for IdP " + idpEndpoint.Id);
                    return;
                }

                Saml20MetadataDocument metadata = endpoint.metadata;

                if (!parser.VerifySignature(metadata.GetKeys(KeyTypes.signing)))
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Invalid signature redirect-binding, msg: " + parser.Message);
                    HandleError(context, Resources.SignatureInvalid);
                    return;
                }

                message = parser.Message;
            }
            else if (context.Request.RequestType == "POST") // HTTP Post binding
            {
                HttpPostBindingParser parser = new HttpPostBindingParser(context);

                if (!parser.IsSigned())
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Signature not present, msg: " + parser.Message);
                    HandleError(context, Resources.SignatureNotPresent);
                }

                IDPEndPoint endpoint = config.FindEndPoint(idpEndpoint.Id);
                if (endpoint.metadata == null)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Cannot find metadata for IdP");
                    HandleError(context, "Cannot find metadata for IdP " + idpEndpoint.Id);
                    return;
                }

                Saml20MetadataDocument metadata = endpoint.metadata;

                // handle a logout-request
                if (!parser.CheckSignature(metadata.GetKeys(KeyTypes.signing)))
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Invalid signature post-binding, msg: " + parser.Message);
                    HandleError(context, Resources.SignatureInvalid);
                }

                message = parser.Message;
            }
            else
            {
                //Error: We don't support HEAD, PUT, CONNECT, TRACE, DELETE and OPTIONS
                HandleError(context, Resources.UnsupportedRequestTypeFormat(context.Request.RequestType));
            }

            AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, message);

            //Log the user out locally
            DoLogout(context, true);

            LogoutRequest req = Serialization.DeserializeFromXmlString <LogoutRequest>(message);

            response.InResponseTo = req.ID;

            //Respond using redirect binding
            if (destination.Binding == SAMLBinding.REDIRECT)
            {
                HttpRedirectBindingBuilder builder = new HttpRedirectBindingBuilder();
                builder.RelayState = context.Request.Params["RelayState"];
                builder.Response   = response.GetXml().OuterXml;
                builder.signingKey = FederationConfig.GetConfig().SigningCertificate.GetCertificate().PrivateKey;
                string s = destination.Url + "?" + builder.ToQuery();
                context.Response.Redirect(s, true);
                return;
            }

            //Respond using post binding
            if (destination.Binding == SAMLBinding.POST)
            {
                HttpPostBindingBuilder builder = new HttpPostBindingBuilder(destination);
                builder.Action = SAMLAction.SAMLResponse;
                XmlDocument responseDocument = response.GetXml();
                XmlSignatureUtils.SignDocument(responseDocument, response.ID);
                builder.Response   = responseDocument.OuterXml;
                builder.RelayState = context.Request.Params["RelayState"];
                builder.GetPage().ProcessRequest(context);
                return;
            }
        }
        private void HandleRequest(HttpContext context)
        {
            Trace.TraceMethodCalled(GetType(), "HandleRequest()");

            //Fetch config object
            SAML20FederationConfig config = SAML20FederationConfig.GetConfig();

            LogoutRequest logoutRequest = null;
            IDPEndPoint   endpoint      = null;
            string        message       = string.Empty;

            //Build the response object
            var response = new Saml20LogoutResponse();

            response.Issuer     = config.ServiceProvider.ID;
            response.StatusCode = Saml20Constants.StatusCodes.Success; // Default success. Is overwritten if something fails.

            if (context.Request.RequestType == "GET")                  // HTTP Redirect binding
            {
                HttpRedirectBindingParser parser = new HttpRedirectBindingParser(context.Request.Url);
                AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST,
                                      string.Format("Binding: redirect, Signature algorithm: {0}  Signature:  {1}, Message: {2}", parser.SignatureAlgorithm, parser.Signature, parser.Message));

                if (!parser.IsSigned)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Signature not present, msg: " + parser.Message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                logoutRequest = parser.LogoutRequest;
                endpoint      = config.FindEndPoint(logoutRequest.Issuer.Value);

                if (endpoint.metadata == null)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Cannot find metadata for IdP: " + logoutRequest.Issuer.Value);
                    // Not able to return a response as we do not know the IdP.
                    HandleError(context, "Cannot find metadata for IdP " + logoutRequest.Issuer.Value);
                    return;
                }

                Saml20MetadataDocument metadata = endpoint.metadata;

                if (!parser.VerifySignature(metadata.GetKeys(KeyTypes.signing)))
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Request has been denied. Invalid signature redirect-binding, msg: " + parser.Message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                message = parser.Message;
            }
            else if (context.Request.RequestType == "POST") // HTTP Post binding
            {
                HttpPostBindingParser parser = new HttpPostBindingParser(context);
                AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST,
                                      "Binding: POST, Message: " + parser.Message);

                if (!parser.IsSigned())
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Signature not present, msg: " + parser.Message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                logoutRequest = parser.LogoutRequest;
                endpoint      = config.FindEndPoint(logoutRequest.Issuer.Value);
                if (endpoint.metadata == null)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Cannot find metadata for IdP");
                    // Not able to return a response as we do not know the IdP.
                    HandleError(context, "Cannot find metadata for IdP " + logoutRequest.Issuer.Value);
                    return;
                }

                if (logoutRequest.NotOnOrAfter.HasValue)
                {
                    var allowedClockSkewTime = DateTime.UtcNow.AddMinutes(FederationConfig.GetConfig().AllowedClockSkewMinutes);

                    if (logoutRequest.NotOnOrAfter >= allowedClockSkewTime)
                    {
                        var errormessage =
                            $"Logout request NotOnOrAfter ({logoutRequest.NotOnOrAfter}) is after allowed time ({allowedClockSkewTime})";
                        AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, errormessage);
                        HandleError(context, errormessage);
                        return;
                    }
                }

                Saml20MetadataDocument metadata = endpoint.metadata;

                // handle a logout-request
                if (!parser.CheckSignature(metadata.GetKeys(KeyTypes.signing)))
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Request has been denied. Invalid signature post-binding, msg: " + parser.Message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }

                message = parser.Message;
            }
            else
            {
                //Error: We don't support HEAD, PUT, CONNECT, TRACE, DELETE and OPTIONS
                // Not able to return a response as we do not understand the request.
                HandleError(context, string.Format(Resources.UnsupportedRequestType, context.Request.RequestType));
                return;
            }

            AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, message);

            // Check that idp in session and request matches.
            string idpRequest = logoutRequest.Issuer.Value;

            // SessionFactory.SessionContext.Current.New is never the first call to Current due to the logic in Application_AuthenticateRequest() ... Saml20Identity.IsInitialized()
            // Hence we need to check on Saml20Identity.IsInitialized() instead of using SessionFactory.SessionContext.Current.New.
            bool isOioSamlSessionActive = Saml20Identity.IsInitialized();

            if (isOioSamlSessionActive)
            {
                object idpId = Saml20PrincipalCache.GetSaml20AssertionLite().Issuer;

                if (idpId != null && idpId.ToString() != idpRequest)
                {
                    AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, string.Format(Resources.IdPMismatchBetweenRequestAndSession, idpId, idpRequest), message);
                    response.StatusCode = Saml20Constants.StatusCodes.RequestDenied;
                }
            }
            else
            {
                // All other status codes than Success results in the IdP throwing an error page. Therefore we return default Success even if we do not have a session.
                AuditLogging.logEntry(Direction.IN, Operation.LOGOUTREQUEST, "Session does not exist. Continues the redirect logout procedure with status code success." + idpRequest, message);
            }

            //  Only logout if request is valid and we are working on an existing Session.
            if (Saml20Constants.StatusCodes.Success == response.StatusCode && isOioSamlSessionActive)
            {
                // Execute all actions that the service provider has configured
                DoLogout(context, true);
            }

            // Update the response object with informations that first is available when request has been parsed.
            IDPEndPointElement destination = DetermineEndpointConfiguration(SAMLBinding.REDIRECT, endpoint.SLOEndpoint, endpoint.metadata.SLOEndpoints());

            response.Destination  = destination.Url;
            response.InResponseTo = logoutRequest.ID;

            //Respond using redirect binding
            var shaHashingAlgorithm = SignatureProviderFactory.ValidateShaHashingAlgorithm(endpoint.ShaHashingAlgorithm);

            if (destination.Binding == SAMLBinding.REDIRECT)
            {
                HttpRedirectBindingBuilder builder = new HttpRedirectBindingBuilder();
                builder.RelayState          = context.Request.Params["RelayState"];
                builder.Response            = response.GetXml().OuterXml;
                builder.signingKey          = FederationConfig.GetConfig().SigningCertificate.GetCertificate().PrivateKey;
                builder.ShaHashingAlgorithm = shaHashingAlgorithm;
                string s = destination.Url + "?" + builder.ToQuery();
                context.Response.Redirect(s, true);
                return;
            }

            //Respond using post binding
            if (destination.Binding == SAMLBinding.POST)
            {
                HttpPostBindingBuilder builder = new HttpPostBindingBuilder(destination);
                builder.Action = SAMLAction.SAMLResponse;
                XmlDocument responseDocument   = response.GetXml();
                var         signingCertificate = FederationConfig.GetConfig().SigningCertificate.GetCertificate();
                var         signatureProvider  = SignatureProviderFactory.CreateFromShaHashingAlgorithmName(shaHashingAlgorithm);
                signatureProvider.SignAssertion(responseDocument, response.ID, signingCertificate);
                builder.Response   = responseDocument.OuterXml;
                builder.RelayState = context.Request.Params["RelayState"];
                builder.GetPage().ProcessRequest(context);
                return;
            }
        }