Added use of async

Author: papafe

src/MongoDB.Driver/Core/Connections/Socks5Helper.cs

@@ -134,6 +134,7 @@ public static async Task PerformSocks5HandshakeAsync(Stream stream, EndPoint end
                 var greetingRequestLength = CreateGreetingRequest(buffer, useAuth);
                 await stream.WriteAsync(buffer, 0, greetingRequestLength, cancellationToken).ConfigureAwait(false);
 
+                await stream.ReadBytesAsync(buffer, 0, 2, cancellationToken).ConfigureAwait(false);
                 var acceptsUsernamePasswordAuth = ProcessGreetingResponse(buffer, useAuth);
 
                 if (useAuth && acceptsUsernamePasswordAuth)

src/MongoDB.Driver/Core/Connections/TcpStreamFactory.cs

@@ -72,7 +72,6 @@ public Stream CreateStream(EndPoint endPoint, CancellationToken cancellationToke
                     Connect(socket, resolved[i], cancellationToken);
                     var stream = CreateNetworkStream(socket);
 
-                    //TODO Need to do the same for the async version and for net472
                     if (useProxy)
                     {
                         Socks5Helper.PerformSocks5Handshake(stream, endPoint, socks5ProxySettings.Authentication, cancellationToken);
@@ -108,7 +107,7 @@ public async Task<Stream> CreateStreamAsync(EndPoint endPoint, CancellationToken
             var stream = CreateNetworkStream(socket);
             if (useProxy)
             {
-                Socks5Helper.PerformSocks5Handshake(stream, endPoint, socks5ProxySettings.Authentication, cancellationToken);
+                await Socks5Helper.PerformSocks5HandshakeAsync(stream, endPoint, socks5ProxySettings.Authentication, cancellationToken).ConfigureAwait(false);
             }
 
             return stream;
@@ -124,7 +123,7 @@ public async Task<Stream> CreateStreamAsync(EndPoint endPoint, CancellationToken
 
                     if (useProxy)
                     {
-                        Socks5Helper.PerformSocks5Handshake(stream, endPoint, socks5ProxySettings.Authentication, cancellationToken);
+                        await Socks5Helper.PerformSocks5HandshakeAsync(stream, endPoint, socks5ProxySettings.Authentication, cancellationToken).ConfigureAwait(false);
                     }
 
                     return stream;