c# - 在 C# 中创建的 Web 代理需要提示进行身份验证

Question

我编写了一个使用 TcpListener 的小型 Web 代理程序，它在特定端口上监听 Web 调用。一旦收到调用，它就会创建一个套接字，获取调用的 header ，将其转发到请求的网页上，读取响应并将其返回给执行请求的客户端。代理很好用，但现在我想通过隐含用户名来限制谁可以通过代理访问网络。我如何将身份验证合并到我的代理上？

这是我的代码:

使用系统；
使用 System.Net；
使用 System.Net.Sockets；
使用 System.Text；
使用 System.IO；
使用 System.Threading；
使用 System.Windows.Forms；
使用 System.Collections.Generic；
使用 System.ComponentModel；
使用 System.Data；
使用 System.Drawing；

命名空间 WebProxy2
{
公共(public)部分类Form1:表格
{
公共(public) bool 代理=假；

    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_Load(object sender, EventArgs e)
    {

    }

    public void log(string logText)
    {
        Application.DoEvents();
        textBox1.Text += logText + "\r\n";
        StreamWriter sw = new StreamWriter(@"c:\proxyLog.txt",true);
        sw.WriteLine(logText);
        sw.Close();
        Application.DoEvents();
    }

    class WebProxy2
    {
        Socket clientSocket;
        Form1 proxyGui;
        Byte[] read = new byte[1024];
        Byte[] Buffer = null;
        Encoding ASCII = Encoding.ASCII;
        const string HTTP_VERSION = "HTTP/1.0";
        const string CRLF = "\r\n";
        Byte[] RecvBytes = new Byte[4096];

        public WebProxy2(Socket socket, Form1 form)
        {
            this.clientSocket = socket;
            this.proxyGui = form;
        }

        public void run()
        {
            Application.DoEvents();
            String clientmessage = " ", sURL = " ";

            int bytes = readmessage(read, ref clientSocket, ref clientmessage);
            if (bytes == 0)
            {
                return;
            }
            int index1 = clientmessage.IndexOf(' ');
            int index2 = clientmessage.IndexOf(' ', index1 + 1);
            if ((index1 == -1) || (index2 == -1))
            {
                throw new IOException();
            }
            proxyGui.log("Connecting to Site: " + clientmessage.Substring(index1 + 1, index2 - index1));
            proxyGui.log("Connection from " + clientSocket.RemoteEndPoint);
            string part1 = clientmessage.Substring(index1 + 1, index2 - index1);
            int index3 = part1.IndexOf('/', index1 + 8);
            int index4 = part1.IndexOf(' ', index1 + 8);
            int index5 = index4 - index3;
            sURL = part1.Substring(index1 + 4, (part1.Length - index5) - 8);
            try
            {


                IPHostEntry IPHost = Dns.Resolve(sURL);
                proxyGui.log("Request resolved: " + IPHost.HostName);
                string[] aliases = IPHost.Aliases;
                IPAddress[] address = IPHost.AddressList;
                proxyGui.log(address[0].ToString());
                IPEndPoint sEndpoint = new IPEndPoint(address[0], 80);
                Socket IPsocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

                IPsocket.Connect(sEndpoint);
                if (IPsocket.Connected)
                    proxyGui.log("Socket connect OK");
                string GET = clientmessage;
                Byte[] ByteGet = ASCII.GetBytes(GET);
                IPsocket.Send(ByteGet, ByteGet.Length, 0);
                Int32 rBytes = IPsocket.Receive(RecvBytes, RecvBytes.Length, 0);
                proxyGui.log("Recieved " + rBytes);
                //Buffer = RecvBytes;
                String strRetPage = null;
                strRetPage = strRetPage + ASCII.GetString(RecvBytes, 0, rBytes);
                while (rBytes > 0)
                {
                    rBytes = IPsocket.Receive(RecvBytes, RecvBytes.Length, 0);
                    strRetPage = strRetPage + ASCII.GetString(RecvBytes, 0, rBytes);
                }
                IPsocket.Shutdown(SocketShutdown.Both);
                IPsocket.Close();
                sendmessage(clientSocket, strRetPage);
            }
            catch (Exception exc2)
            {
                proxyGui.log(exc2.ToString());
            }
        }

        private int readmessage(byte[] ByteArray, ref Socket s, ref String clientmessage)
        {

            int bytes = s.Receive(ByteArray, 1024, 0);
            string messagefromclient = Encoding.ASCII.GetString(ByteArray);
            clientmessage = (String)messagefromclient;
            return bytes;
        }
        private void sendmessage(Socket s, string message)
        {
            Buffer = new Byte[message.Length + 1];
            int length = ASCII.GetBytes(message, 0, message.Length, Buffer, 0);
            s.Send(Buffer, length, 0);
        }

    }

    const int port = 8080;
    TcpListener tcplistener = new TcpListener(port);
    private void btnProxy_Click_1(object sender, EventArgs e)
    {
        proxyOn = true;
        log("Listening on port " + port + " " + DateTime.Now.ToString());

        tcplistener.Start();
        while (proxyOn)
        {
            Application.DoEvents();
            if (tcplistener.Pending())
            {
                Socket socket = tcplistener.AcceptSocket();
                WebProxy2 webproxy = new WebProxy2(socket, this);
                webproxy.run();
            }
         Application.DoEvents();
        }
    }

    private void btnStop_Click_1(object sender, EventArgs e)
    {
        Application.DoEvents();
        proxyOn = false;
        tcplistener.Stop();
        log("Proxy stopped !!! " + DateTime.Now.ToString());
        Application.DoEvents();
    }

}

}

Answer 1

不清楚您是实现了自己的 HTTP 代理协议(protocol)(或多或少是基于 Host header 的简单 TCP 重定向)还是使用标准 HTTP 代理协议(protocol)。

如果您选择标准代理(这可能更好，除非您有充分的理由不这样做)，您应该可以使用 Proxy-Authenticate , Proxy-Authorization和 Proxy-Authentication-Info标题而不是 WWW-Authenticate , Authorization和 Authentication-Info (分别)例如用于 HTTP Basic 或 Digest 身份验证。