TCP TLS communication in Xamarin Forms Application

Question

I want to establish connection between the client and server over TCP using TLS in my Xamarin forms Application. I am facing issues making a successful connection using certificate. Please guide me.

Answer 1

I would say you could do it using MQTTnet but I am having similar issues connecting to aws.

private async Task OnConnectToIoTHubCommandAsync()
{
const string server = "sample.amazonaws.com";
const string clientId = "XXXXXXXXXXKELYG82g";
const string machineId = "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXX";
const string topic = "helloServer" + machineId;

            byte[] caCertRawBytes;
            byte[] clientCertRawBytes;

            using (var stream = await FileSystem.OpenAppPackageFileAsync("AmazonRootCA1.crt"))
            {
                using (var memoryStream = new MemoryStream())
                {
                    stream.CopyTo(memoryStream);
                    caCertRawBytes = memoryStream.ToArray();
                }
            }

            using (var stream = await FileSystem.OpenAppPackageFileAsync("Private.pfx"))
            {
                using (var memoryStream = new MemoryStream())
                {
                    stream.CopyTo(memoryStream);
                    clientCertRawBytes = memoryStream.ToArray();
                }
            }

            var caCert = new X509Certificate(caCertRawBytes);
            var clientCert = new X509Certificate2(clientCertRawBytes, "PfxPassword"); 

            var source = new CancellationTokenSource();
            var token = source.Token;

            var mqttOptions = new MqttClientOptionsBuilder()
                                  .WithTcpServer(server, 8883)
                                  .WithTls(new MqttClientOptionsBuilderTlsParameters
                                  {
                                      UseTls = true,
                                      Certificates = new List<X509Certificate> { caCert, clientCert },
                                      AllowUntrustedCertificates = false,
                                      IgnoreCertificateChainErrors = false,
                                      IgnoreCertificateRevocationErrors = false,
                                  })
                                  .Build();

            // Create a new MQTT client.
            var mqttClient = new MqttFactory().CreateMqttClient();
            await mqttClient.ConnectAsync(mqttOptions, token);
            await Task.CompletedTask.ConfigureAwait(false);
        }

The output is an authentication failed see inner exception but the only thing in there is a System Exception exception and a timeout. I'm posting because my problem seems to be closely related to yours. The pfx file is a combination of the thing cert and the private key.