How to use Proxy with TcpClient.ConnectAsync()?

Question

HTTP proxy support in .NET does not actually support the lower level classes like TcpClient or Socket. But I want to connect a TCPServer (ip, port) through HTTP proxy that s

Answer 1

I find a solution base on .NET: Connecting a TcpClient through an HTTP proxy with authentication and Bypass the proxy using TcpClient

TcpClient _client;
NetworkStream _stream;

public TcpClient ProxyTcpClient(string targetHost, int targetPort, string httpProxyHost, int httpProxyPort, string proxyUserName, string proxyPassword)
{
        const BindingFlags Flags = BindingFlags.NonPublic | BindingFlags.Instance;
        Uri proxyUri = new UriBuilder
        {
            Scheme = Uri.UriSchemeHttp,
            Host = httpProxyHost,
            Port = httpProxyPort
        }.Uri;
        Uri targetUri = new UriBuilder
        {
             Scheme = Uri.UriSchemeHttp,
             Host = targetHost,
             Port = targetPort
        }.Uri;

        WebProxy webProxy = new WebProxy(proxyUri, true);
        webProxy.Credentials = new NetworkCredential(proxyUserName, proxyPassword);
        WebRequest request = WebRequest.Create(targetUri);
        request.Proxy = webProxy;
        request.Method = "CONNECT";
        HttpWebResponse response = (HttpWebResponse)request.GetResponse();
        Stream responseStream = response.GetResponseStream();
        Type responseType = responseStream.GetType();
        PropertyInfo connectionProperty = responseType.GetProperty("Connection", Flags);
        var connection = connectionProperty.GetValue(responseStream, null);
        Type connectionType = connection.GetType();
        PropertyInfo networkStreamProperty = connectionType.GetProperty("NetworkStream", Flags);
        NetworkStream networkStream = (NetworkStream)networkStreamProperty.GetValue(connection, null);
        Type nsType = networkStream.GetType();
        PropertyInfo socketProperty = nsType.GetProperty("Socket", Flags);
        Socket socket = (Socket)socketProperty.GetValue(networkStream, null);

        return new TcpClient { Client = socket };
}

public static async Task ConnectAsync(string hostname, int port)
{
        _client = ProxyTcpClient("IPTargetHost", 1234, "IPProxyHost", 5678, "Userproxy", "Userppwd");
        _stream = conn._client.GetStream();

        ..... Do some stuff

        // Connexion OK
        return true;
}