[script]send fake gateway arp probe response to node

[san3xian]

[script]send fake gateway arp probe response to node

[san3Xian]

极速面向搜索引擎改良，自动识别source mac address
没有检查有没有bug
慎用

# !/usr/bin/python
# -*- coding: UTF-8 -*-

import os
import sys
import signal
from scapy.all import (
    get_if_hwaddr,   # 获取本机网络接口的函数
    getmacbyip,      # 通过IP地址获取其Mac地址的函数
    ARP,             # 构造ARP数据包
    Ether,           # 构造以太网数据包
    sendp,           # 在第二层发送数据包
    sniff            # capture network traffic
)

from optparse import OptionParser     #格式化用户输入的参数

# build arp response package
def build_rep(src_ipaddr, src_mac, dst_ipaddr, dst_mac ):
   pkt = Ether(src=src_mac, dst=dst_mac) / ARP(hwsrc=src_mac, psrc=src_ipaddr, hwdst=dst_mac, pdst=dst_ipaddr, op=2)
   return pkt

def sniff_callback(package):
    global gw_mac
    print("get a arp probe package from {}".format(package.src))
    pkt = build_rep(src_ipaddr=package.pdst, src_mac=gw_mac, dst_ipaddr=package.psrc, dst_mac=package.hwsrc)
    sendp(pkt, inter=0, iface=options.interface)

def quit(signum, frame):
        print('\nYou choose to stop me.')
        exit()

def main():
 
    #自定义程序使用方法，当中的 %prog，optparse会以当前程序名的字符串来替代
    usage = 'Usage: %prog [-i interface] [--gateway gateway_ip]'
 
    #创建一个 OptionParser 对象
    parser = OptionParser(usage)
    #add_option 来定义命令行参数
    parser.add_option('-i', dest='interface', default="dce-br", help='Specify the interface to use')
    parser.add_option('--gateway',dest="gatewayip",help="gateway ip address")
 
    global options
    (options, args) = parser.parse_args()

    signal.signal(signal.SIGINT, quit)
 
    if options.interface is None or options.gatewayip is None:
        parser.print_help()
        print("[debug]interface value is  ",options.interface)
        print("[debug]gateway ip value is ",options.gatewayip)
        sys.exit(1)

    # get gateway mac address
    global gw_mac
    gw_mac = getmacbyip(options.gatewayip)
    print("gateway ip address is:{}, mac address is: {}".format(options.gatewayip, gw_mac)) 

    sniff_filter = "arp and src 0.0.0.0 and dst " + options.gatewayip
    sniff(iface=options.interface, filter=sniff_filter, prn=sniff_callback)
     
if __name__ == '__main__':
    main()