python网络套接字_Python中利用原始套接字进行网络编程的示例

在实验中需要自己构造单独的HTTP数据报文&＃xff0c;而使用SOCK_STREAM进行发送数据包&＃xff0c;需要进行完整的TCP交互。

因此想使用原始套接字进行编程&＃xff0c;直接构造数据包&＃xff0c;并在IP层进行发送&＃xff0c;即采用SOCK_RAW进行数据发送。

使用SOCK_RAW的优势是&＃xff0c;可以对数据包进行完整的修改&＃xff0c;可以处理IP层上的所有数据包&＃xff0c;对各字段进行修改&＃xff0c;而不受UDP和TCP的限制。

下面开始构造HTTP数据包&＃xff0c;

IP层和TCP层使用python的Impacket库&＃xff0c;http内容自行填写。

#!/usr/bin/env python

#-------------------------------------------------------------------------------

# Name: raw_http.py

# Purpose: construct a raw http get packet

#

# Author: Yangjun

#

# Created: 08/02/2014

# Copyright: (c) Yangjun 2014

# Licence:

#-------------------------------------------------------------------------------

import sys

import socket

from impacket import ImpactDecoder, ImpactPacket

def main():

if len(sys.argv) <3:

print "Use: %s " % sys.argv[0]

print "Use: %s " % sys.argv[0]

sys.exit(1)

elif len(sys.argv) &＃61;&＃61; 3:

src &＃61; sys.argv[1]

dst &＃61; sys.argv[2]

cnt &＃61; 1

elif len(sys.argv) &＃61;&＃61;4:

src &＃61; sys.argv[1]

dst &＃61; sys.argv[2]

cnt &＃61; sys.argv[3]

else:

print "Input error!"

sys.exit(1)

#print src, dst

ip &＃61; ImpactPacket.IP()

ip.set_ip_src(src)

ip.set_ip_dst(dst)

# Create a new ICMP packet of type ECHO.

icmp &＃61; ImpactPacket.ICMP()

tcp &＃61; ImpactPacket.TCP()

tcp.set_th_sport(55968)

tcp.set_th_dport(80)

tcp.set_th_seq(1)

tcp.set_th_ack(1)

tcp.set_th_flags(0x18)

tcp.set_th_win(64)

tcp.contains( ImpactPacket.Data("GET /att/DIYLife/41264/528 HTTP/1.1\r\nHost: 192.168.111.1\r\nAccept-Encoding: identity\r\n\r\n"))

ip.contains(tcp)

# Open a raw socket. Special permissions are usually required.

s &＃61; socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_TCP)

s.setsockopt(socket.IPPROTO_IP, socket.IP_HDRINCL, 1)

seq_id &＃61; 0

while cnt >&＃61; 1:

# Calculate its checksum.

seq_id &＃61; seq_id &＃43; 1

tcp.set_th_seq(seq_id)

tcp.calculate_checksum()

# Send it to the target host.

s.sendto(ip.get_packet(), (dst,80))

cnt&＃61; cnt -1

if __name__ &＃61;&＃61; &＃39;__main__&＃39;:

main()