public async Task SignaturesMatchKnownGood() {
			Protocol protocol = Protocol.V20;
			var settings = new ProviderSecuritySettings();
			var cryptoStore = new MemoryCryptoKeyStore();
			byte[] associationSecret = Convert.FromBase64String("rsSwv1zPWfjPRQU80hciu8FPDC+GONAMJQ/AvSo1a2M=");
			string handle = "mock";
			cryptoStore.StoreKey(ProviderAssociationKeyStorage.SharedAssociationBucket, handle, new CryptoKey(associationSecret, DateTime.UtcNow.AddDays(1)));

			var store = new ProviderAssociationKeyStorage(cryptoStore);
			SigningBindingElement signer = new ProviderSigningBindingElement(store, settings);
			signer.Channel = new TestChannel(this.MessageDescriptions);

			IndirectSignedResponse message = new IndirectSignedResponse(protocol.Version, new Uri("http://rp"));
			ITamperResistantOpenIdMessage signedMessage = message;
			message.ProviderEndpoint = new Uri("http://provider");
			signedMessage.UtcCreationDate = DateTime.Parse("1/1/2009");
			signedMessage.AssociationHandle = handle;
			Assert.IsNotNull(await signer.ProcessOutgoingMessageAsync(message, CancellationToken.None));
			Assert.AreEqual("o9+uN7qTaUS9v0otbHTuNAtbkpBm14+es9QnNo6IHD4=", signedMessage.Signature);
		}
		public async Task SignedResponsesIncludeExtraDataInSignature() {
			Protocol protocol = Protocol.Default;
			SigningBindingElement sbe = new ProviderSigningBindingElement(new ProviderAssociationHandleEncoder(new MemoryCryptoKeyStore()), new ProviderSecuritySettings());
			sbe.Channel = new TestChannel(this.MessageDescriptions);
			IndirectSignedResponse response = new IndirectSignedResponse(protocol.Version, RPUri);
			response.ReturnTo = RPUri;
			response.ProviderEndpoint = OPUri;

			response.ExtraData["someunsigned"] = "value";
			response.ExtraData["openid.somesigned"] = "value";

			Assert.IsNotNull(await sbe.ProcessOutgoingMessageAsync(response, CancellationToken.None));
			ITamperResistantOpenIdMessage signedResponse = (ITamperResistantOpenIdMessage)response;

			// Make sure that the extra parameters are signed.
			// Since the signing algorithm only allows for signing parameters that start with
			// 'openid.', other parameters should not be signed.
			Assert.IsNotNull(signedResponse.SignedParameterOrder);
			string[] signedParameters = signedResponse.SignedParameterOrder.Split(',');
			Assert.IsTrue(signedParameters.Contains("somesigned"));
			Assert.IsFalse(signedParameters.Contains("someunsigned"));
		}