Python原始套接字编程

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

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

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

下面开始构造HTTP数据包，

IP层和TCP层使用python的Impacket库，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:       <your licence>#-------------------------------------------------------------------------------import sysimport socketfrom impacket import ImpactDecoder, ImpactPacketdef main():	if len(sys.argv) < 3:		PRint "Use: %s <src ip> <dst ip>" % sys.argv[0]		print "Use: %s <src ip> <dst ip> <cnt>" % sys.argv[0]		sys.exit(1)	elif len(sys.argv) == 3:		src = sys.argv[1]		dst = sys.argv[2]		cnt = 1	elif len(sys.argv) ==4:		src = sys.argv[1]		dst = sys.argv[2]		cnt = sys.argv[3]	else:		print "Input error!"		sys.exit(1)#print src, dst	ip = ImpactPacket.IP()	ip.set_ip_src(src)	ip.set_ip_dst(dst)	# Create a new ICMP packet of type ECHO.	icmp = ImpactPacket.ICMP()	tcp = 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 = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_TCP)	s.setsockopt(socket.IPPROTO_IP, socket.IP_HDRINCL, 1)	seq_id = 0	while cnt >= 1:		# Calculate its checksum.		seq_id = seq_id + 1		tcp.set_th_seq(seq_id)		tcp.calculate_checksum()		# Send it to the target host.		s.sendto(ip.get_packet(), (dst,80))		cnt= cnt -1if __name__ == '__main__':	main()

运行后抓包如下：