System.Net.Security.SslStream.AuthenticateAsServerAsync C# (CSharp) Method

        public virtual System.Threading.Tasks.Task AuthenticateAsServerAsync(System.Security.Cryptography.X509Certificates.X509Certificate serverCertificate) { throw null; }
        public virtual System.Threading.Tasks.Task AuthenticateAsServerAsync(System.Security.Cryptography.X509Certificates.X509Certificate serverCertificate, bool clientCertificateRequired, System.Security.Authentication.SslProtocols enabledSslProtocols, bool checkCertificateRevocation) { throw null; }

        public static void Main(string[] args)
        {
            Console.WriteLine("Starting...");
            X509Certificate2 serverCertificate = new X509Certificate2("certificate.pfx"); // Any valid certificate with private key will work fine.
            TcpListener listener = new TcpListener(IPAddress.Any, 4567);
            TcpClient client = new TcpClient();
            listener.Start();

            Task clientConnectTask = client.ConnectAsync(IPAddress.Loopback, 4567);
            Task<TcpClient> listenerAcceptTask = listener.AcceptTcpClientAsync();
            Task.WaitAll(clientConnectTask, listenerAcceptTask);

            TcpClient server = listenerAcceptTask.Result;
            SslStream clientStream = new SslStream(client.GetStream(), false, new RemoteCertificateValidationCallback(ValidateServerCertificate), null, EncryptionPolicy.RequireEncryption);
            SslStream serverStream = new SslStream(server.GetStream(), false, null, null, EncryptionPolicy.RequireEncryption);

            Task clientAuthenticationTask = clientStream.AuthenticateAsClientAsync(serverCertificate.GetNameInfo(X509NameType.SimpleName, false), null, SslProtocols.Tls12, false);
            Task serverAuthenticationTask = serverStream.AuthenticateAsServerAsync(serverCertificate, false, SslProtocols.Tls12, false);
            Task.WaitAll(clientAuthenticationTask, serverAuthenticationTask);
            
            byte[] readBuffer = new byte[256];
            Task<int> readTask = clientStream.ReadAsync(readBuffer, 0, readBuffer.Length); // Create a pending ReadAsync, which will wait for data that will never come (for testing purposes).
            byte[] writeBuffer = new byte[256];
            Task writeTask = clientStream.WriteAsync(writeBuffer, 0, writeBuffer.Length); // The main thread actually blocks here (not asychronously waits) on .NET Core making this call.
            bool result = Task.WaitAll(new Task[1] { writeTask }, 5000); // This code won't even be reached on .NET Core. Works fine on .NET Framework.

            if (result)
            {
                Console.WriteLine("WriteAsync completed successfully while ReadAsync was pending... nothing locked up.");
            }
            else
            {
                Console.WriteLine("WriteAsync failed to complete after 5 seconds.");
            }
        }