Socket抓包实例(using wireshark)

转自：http://hi.baidu.com/lewutian/blog/item/594e9ff414de1965ddc47408.html

本文使用ServerSocket编写服务端，Socket编写客户端，或者使用NIO也行。然后使用Wireshark抓包。

所有程序在Eclipse测试通过，不过服务器和客户端要在不同的机器上运行，这是因为Wireshark不抓loopback包的问题。

我是在虚拟机中Run的，并且把虚拟机的网络连接设置成“桥”。

如下所示1-3步为程序，4步为抓包结果。

1.Server

package net;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;

class ThreadedServer {

public static void main(String args[]) throws Exception {
    int port = 52333;
    ServerSocket ss = new ServerSocket(port);
    System.out.println("Server started");
    while (true) {
      Socket s = ss.accept();
      System.out.println("accept client");
      ServerThread st = new ServerThread(s);     
      st.start();
      System.out.println("start thread");
    }
}
}

class ServerThread extends Thread {

DataInputStream dis;

DataOutputStream dos;

public ServerThread(Socket s) throws Exception {
    InputStream is = s.getInputStream();
    dis = new DataInputStream(is);
    OutputStream os = s.getOutputStream();
    dos = new DataOutputStream(os);
}

public void run() {
    try {
      while (true) {
        byte[] bytes = new byte[20];
        dis.read(bytes);
        System.out.println("read bytes is " + new String(bytes));

        dos.write(bytes);
        System.out.println("write return value " + new String(bytes));
      }
    } catch (Exception e) {
    }
}
}

2.Client

package net;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;

class Client
{

    public static void main(String args[])
        throws Exception
    {
        int c;
        Socket s = new Socket("192.158.126.136", 52333);
        System.out.println("connect to 192.158.126.136:52333");
        InputStream in = s.getInputStream();
        OutputStream out = s.getOutputStream();

        DataOutputStream dos = new DataOutputStream(out);
        DataInputStream dis = new DataInputStream(in);

        dos.write("maxlisa0102221122001212122121252".getBytes());
        // dos.writeInt(12);
        System.out.println("write maxlisa");

        System.out.print("return value: ");
        byte bytes[] = new byte[3];
        while((c = in.read(bytes)) != -1)
        {
            System.out.print(new String(bytes));
        }
        s.close();
        System.out.println("close connection");
    }
}

3.or using NIO Client

package net;

import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.util.Set;

public class NIOClient
{

    public static void main(String[] args)
        throws Exception
    {
        SocketChannel sc = SocketChannel.open();
        ByteBuffer buffer = ByteBuffer.allocate(1024);
        Selector selector = Selector.open();
        buffer.put("maxlisa test".getBytes());
        buffer.flip();

        sc.configureBlocking(false);
        sc.register(selector, SelectionKey.OP_READ );
       
        sc.connect(new InetSocketAddress("192.158.126.136", 52333));
        while(!sc.finishConnect());
       
        sc.write(buffer);
       
        System.out.println("select operate");
        Thread.sleep(10000);
        int sum = selector.select();
        while(selector.select() > 0)
        {
            Thread.sleep(100);

            Set set = selector.selectedKeys();

            for(SelectionKey key : set)
            {
                int ops = key.readyOps();

                if((ops & SelectionKey.OP_READ) == SelectionKey.OP_READ)
                {
                    sc.read(buffer);
                    buffer.flip();
                }
            }
            selector.selectedKeys().clear();
        }
    }

}

4.TCP PDU LIST

No.     Time        Source                Destination           Protocol Info
1 0.000000    192.158.125.222       192.158.126.136       TCP      38702 > 52333 [SYN] Seq=0 Win=5840 Len=0 MSS=1460 TSV=30156603 TSER=0 WS=7
2 0.000053    192.158.126.136       192.158.125.222       TCP      52333 > 38702 [SYN, ACK] Seq=0 Ack=1 Win=64240 Len=0 MSS=1460 WS=0 TSV=0 TSER=0
3 0.000136    192.158.125.222       192.158.126.136       TCP      38702 > 52333 [ACK] Seq=1 Ack=1 Win=5888 Len=0 TSV=30156603 TSER=0
4 0.001433    192.158.125.222       192.158.126.136       TCP      38702 > 52333 [PSH, ACK] Seq=1 Ack=1 Win=5888 Len=32 TSV=30156604 TSER=0
5 0.001775    192.158.126.136       192.158.125.222       TCP      52333 > 38702 [PSH, ACK] Seq=1 Ack=33 Win=64208 Len=20 TSV=296107 TSER=30156604
6 0.001827    192.158.125.222       192.158.126.136       TCP      38702 > 52333 [ACK] Seq=33 Ack=21 Win=5888 Len=0 TSV=30156605 TSER=296107
7 0.002141    192.158.126.136       192.158.125.222       TCP      52333 > 38702 [PSH, ACK] Seq=21 Ack=33 Win=64208 Len=20 TSV=296107 TSER=30156604
8 0.002191    192.158.125.222       192.158.126.136       TCP      38702 > 52333 [ACK] Seq=33 Ack=41 Win=5888 Len=0 TSV=30156605 TSER=296107
9 7.844516    192.158.125.222       192.158.126.136       TCP      38702 > 52333 [FIN, ACK] Seq=33 Ack=41 Win=5888 Len=0 TSV=30164412 TSER=296107
10 7.844576    192.158.126.136       192.158.125.222       TCP      52333 > 38702 [ACK] Seq=41 Ack=34 Win=64208 Len=0 TSV=296186 TSER=30164412
11 7.844894    192.158.126.136       192.158.125.222       TCP      52333 > 38702 [PSH, ACK] Seq=41 Ack=34 Win=64208 Len=20 TSV=296186 TSER=30164412
12 7.844934    192.158.125.222       192.158.126.136       TCP      38702 > 52333 [RST] Seq=34 Win=0 Len=0