Does anyone know how to use m2mqtt on Unity3D (with Tls1.2)?

I am developing an AR app in Unity and I need to connect to an MQTT broker with TLS protocol enabled.

I am able to connect to non-TLS enabled MQTT brokers successfully(In unity), and I can use the certificate the admin gave me with the MQTT explorer application to connect to the TLS enabled broker successfully. (the broker is using TLS 1.2)

But when I attempt to connect to the TLS enabled server with the paho-m2mqtt library for c# in Unity (https://github.com/eclipse/paho.mqtt.m2mqtt), I get the following exception:

Connection error: uPLibrary.Networking.M2Mqtt.Exceptions.MqttConnectionException: Exception connecting to the broker

---> System.ArgumentException: SSL/TLS protocol version not supported

This is the code I am using to test the connection (I have the server certificate, client certificate, and client key stored at Assets/StreamingAssests, and I could be using the certs wrong when making the MqttClient, but this is how most people were connecting):

Code (CSharp):

1. public void connect(broker, port)
2. {
3.     string caCertLoc = Application.streamingAssetsPath + "/ca.crt";
4.     string clientCertLoc = Application.streamingAssetsPath + "/clientCert.crt";
5.  
6.     X509Certificate2 caCert = new X509Certificate2(caCertLoc);
7.  
8.     X509Certificate2 clientCert = new X509Certificate2(clientCertLoc);
9.  
10.     MqttClient client = new MqttClient(broker, port, true,
11.                                        X509Certificate.CreateFromCertFile(caCertLoc),
12.                                        X509Certificate2.CreateFromCertFile(clientCertLoc),
13.                                        MqttSslProtocols.TLSv1_2,
14.                                        MyRemoteCertificateValidationCallback);
15.  
16.     string clientId = Guid.NewGuid().ToString();
17.  
18.     try
19.     {
20.         client.Connect(clientId);
21.     }
22.     catch (Exception e)
23.     {
24.         UnityEngine.Debug.LogError("Connection error: " + e);
25.     }
26. }

I would appreciate any help as I am completely stuck on this.

 

Did you find any solution to this problem? Facing the same issue