前言：
有些公司不让员工上Q或封掉某些网站，这时候，干着急没办法，只能鄱墙。
如果上网搜代理IP，很少能用，用HTTP-Tunnel Client代理软件，免费的也是经常性的掉线。
正好手头上有N台服务器，如果直接在上面装个CCProxy，也显的太明显了。
于是自己写个代理软件放上去，一来包装一下好伪装，二来又有代理功能，看着挺好。
原理解说：
1：创建一个Socket进行本地端口监听-》一个死循环while语句
2：收到消息时，产生一个线程处理->多线程处理并发请求
3：产生一个新的Socket负责转发和接收
4：原来的Socket负责把新接收的消息发送回客户端
代码细说
说明：本次示例在控制台程序里运行。
一：Program.cs
1：简单函数原型
using System;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;
using System.Net.Sockets;
using System.Threading;
namespace TcpProxy
{
/// <summary>
/// by 路过秋天
/// http://www.cnblogs.com/cyq1162
/// </summary>
class Program
{
static void Main(string[] args)
{
Listen(808);//起始监听808和CCProxy一样。
}
static void Write(string msg)//简化消息输出
{
Console.WriteLine(msg);
}
static void Listen(int port)//开始监听
{
}
static void ReListen(TcpListener listener)//监听失败，需要重新换端口监听
{
}
}
}
2：开始监听
static void Listen(int port)//开始监听
{
Write("准备监听端口:" + port);
System.Net.IPAddress ipp = System.Net.IPAddress.Parse("0.0.0.0");//监听本地任意IP
TcpListener tcplistener = new TcpListener(ipp, port);
//端口复用，xp下可以复用[可抢占IIS80端口],win2003下无效。
tcplistener.Server.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
try
{
tcplistener.Start();
}
catch (Exception err)
{
Write(err.Message);
Write("该端口已被占用,请更换端口号!!!");
ReListen(tcplistener);//监听失败，切换端口监听
}
//下面还有代码，暂时省略
}
3：监听失败，切换端口监听
static void ReListen(TcpListener listener)//监听失败，需要重新换端口监听
{
if (listener != null)
{
listener.Stop();
listener = null;
}
Write("请输入监听端口号:");
string newPort = Console.ReadLine();
int port;
if (int.TryParse(newPort, out port))
{
Listen(port);
}
else
{
ReListen(listener);
}
}
4：开始监听，进入死循环
static void Listen(int port)//开始监听
{
//上面代码省略......
Write("成功监听端口:" + port);
Socket socket;
while (true)
{
socket = tcplistener.AcceptSocket();//获取传送和接收数据的Scoket实例
Proxy proxy = new Proxy(socket);//Proxy类实例化
Thread thread = new Thread(new ThreadStart(proxy.Run));//创建线程
thread.Start();//启动线程
}
}
作者：路过秋天
博客：http://cyq1162.cnblogs.com/
二：Proxy.cs
Proxy简单函数原型：
using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.IO;
namespace TcpProxy
{
/// <summary>
/// by 路过秋天
/// http://www.cnblogs.com/cyq1162
/// </summary>
public class Proxy
{
Socket clientSocket;//接收和返回
byte[] read = null;//存储来自客户端请求数据包
byte[] sendBytes = null;//存储中转请求发送的数据
byte[] recvBytes = null;//存储中转请求返回的数据
bool isConnect = false;
byte[] qqSendBytes=new byte[4096];//QQ发送缓冲
byte[] qqRecvBytes = new byte[4096];//QQ接收缓冲
int sendLength = 0, recvLength = 0;//实际发送和接收长度
public Proxy(Socket socket)//初始化
{
clientSocket = socket;
recvBytes = new Byte[1024 * 1024];
clientSocket.ReceiveBufferSize = recvBytes.Length;
clientSocket.SendBufferSize = recvBytes.Length;
}
public void Run(){}//主运行代码
//从请求头里解析出url和端口号
private string GetUrl(string clientmessage, ref int port){}
//接收客户端的HTTP请求数据
private int ReadMessage(byte[] readByte, ref Socket s, ref IPAddress ipAddress, ref string host, ref int port){}
//关闭socket
private void CloseSocket(Socket socket){}
private void CloseSocket(Socket socket, bool shutdown){}
//QQ代理测试返回
private byte[] QQokProxyData(){}
//firfox默认会发送一些请求，很烦，所以加过滤
private bool Filter(string url){ }
private void Write(string msg)
{
System.Console.WriteLine(msg);
}
}
}
Run主函数
A：分解请求头，获取要请求的IP，端口
#region 获取客户端请求数据
Write("-----------------------------请求开始---------------------------");
read = new byte[clientSocket.Available];
IPAddress ipAddress = IPAddress.Any;
string host = "";//主机
int port = 80;//端口
int bytes = ReadMessage(read, ref clientSocket, ref ipAddress, ref host, ref port);
if (bytes == 0)
{
Write("读取不到数据!");
CloseSocket(clientSocket);
return;
}
#endregion
Run函数分解：ReadMessage函数
//接收客户端的HTTP请求数据
private int ReadMessage(byte[] readByte, ref Socket s, ref IPAddress ipAddress, ref string host, ref int port)
{
try
{
int bytes = s.Receive(readByte, readByte.Length, 0);
Write("收到原始请求数据：" + readByte.Length);
string header = Encoding.ASCII.GetString(readByte);
host = GetUrl(header, ref port);
if (Filter(host))
{
Write("系统过滤:" + host);
return 0;
}
Write(header);
ipAddress = Dns.GetHostAddresses(host)[0];
if (!isConnect)
{
header = header.Replace("http://" + host, "");
}
sendBytes = Encoding.ASCII.GetBytes(header);
System.Threading.Thread.Sleep(50);
Write("转发请求数据：" + sendBytes.Length);
Write(Encoding.ASCII.GetString(sendBytes));
return bytes;
}
catch
{
System.Threading.Thread.Sleep(300);
return 0;
}
}
ReadMessage函数分解：GetUrl
//从请求头里解析出url和端口号
private string GetUrl(string clientmessage, ref int port)
{
if (clientmessage.IndexOf("CONNECT") != -1)
{
isConnect = true;
}
int index1 = clientmessage.IndexOf(' ');
int index2 = clientmessage.IndexOf(' ', index1 + 1);
if ((index1 == -1) || (index2 == -1))
{
return "";
}
string part1 = clientmessage.Substring(index1 + 1, index2 - index1).Trim();
string url = string.Empty;
if (!part1.Contains("http://"))
{
if (part1.Substring(0, 1) == "/")
{
part1 = "127.0.0.1" + part1;
}
part1 = "http://" + part1;
}
Uri uri = null;
try
{
uri = new Uri(part1);
}
catch
{
return "";
}
url = uri.Host;
port = uri.Port;
return url;
}
ReadMessage函数分解：Filter
private bool Filter(string url)
{
switch (url.ToLower())
{
case "fffocus.cn":
return true;
}
return false;
}
Run函数分解：CloseSocket函数
private void CloseSocket(Socket socket)
{
CloseSocket(socket, true);
}
private void CloseSocket(Socket socket, bool shutdown)
{
if (socket != null)
{
if (shutdown)
{
socket.Shutdown(SocketShutdown.Both);
}
socket.Close();
}
}
B：创建中转Socket及建立连接
#region 创建中转Socket及建立连接
IPEndPoint ipEndpoint = new IPEndPoint(ipAddress, port);
Socket IPsocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
try
{
IPsocket.Connect(ipEndpoint); Write("-----Socket 建立连接！ IP地址：" + ipAddress + "网址：http://" + host);
}
catch (Exception err)
{
Write("连接失败 ：" + err.Message);
Write("退出请求!!!");
CloseSocket(IPsocket, false);
return;
}
#endregion
C：QQ代理测试及网页转发
if (isConnect)//QQ链接方式
{
byte[] qqOkData = QQokProxyData();
clientSocket.Send(qqOkData, 0, qqOkData.Length, 0);
}
else//正常网页，直接转发
{
IPsocket.Send(sendBytes, 0);
}
函数分解：QQokProxyData
private byte[] QQokProxyData()
{
string data = "HTTP/1.0 200 Connection established";//返回建立成功";
return System.Text.Encoding.ASCII.GetBytes(data);
}
D：针对QQ需要进行重复来回的发送与接收
#region QQ发送/接收中转请求
int length = 0, count = 0;
if (isConnect)
{
System.Threading.Thread.Sleep(400);//关键时延
//循环发送客户端请求,接收服务器返回
DateTime start = DateTime.Now;
while (true)
{
if (IPsocket.Available == 0 && clientSocket.Available == 0)
{
if (((TimeSpan)(DateTime.Now - start)).TotalMinutes > 15)
{
break;//掉线重拔处理
}
}
else
{
start = DateTime.Now;
}
try
{
while (clientSocket.Available != 0)
{
sendLength = clientSocket.Receive(qqSendBytes, qqSendBytes.Length, 0);
IPsocket.Send(qqSendBytes, sendLength, 0);
Write("发送字节数: " + sendLength.ToString());
}
System.Threading.Thread.Sleep(500);
while (IPsocket.Available != 0)
{
recvLength = IPsocket.Receive(qqRecvBytes, qqRecvBytes.Length, 0);
clientSocket.Send(qqRecvBytes, recvLength, 0);
Write("接收字节数: " + recvLength.ToString());
}
}
catch
{
}
}
}
else
{
try
{
do
{
length = IPsocket.Receive(recvBytes, count, IPsocket.Available, 0);
count = count + length;
Write("接收转发请求返回的数据中..." + length);
System.Threading.Thread.Sleep(200);//关键点,请求太快数据接收不全
}
while (IPsocket.Available > 0);
clientSocket.Send(recvBytes, 0, count, 0);
}
catch(Exception err)
{
Write(err.Message);
}
}
#endregion
E：结束请求,关闭客户端Socket
#region 结束请求,关闭客户端Socket
Write("接收完成。返回客户端数据..." + count);
CloseSocket(IPsocket);
CloseSocket(clientSocket);
recvBytes = null;
Write("本次请求完成,已关闭连接...");
Write("-----------------------------请求结束---------------------------");
#endregion
结言：
本QQ代理软件在服务器上运行长达三个多月,使用过程未发现异常退出情况。当然前提就我一个人在用了~哈哈~