KISS dns mitm gist which demonstratoes how to relay dns requests (to cloudflare in this case) unsing only a few lines of code

dnsmitm.py

#!/usr/bin/env python3
import socket
import os

# Beware: this is a navive KISS implementation of a DNS MITM relaying server
# It therefor has no timeouts and other safeguards preventing resource exausstion
# and since it forks you can run out of PIDS's pretty fast is a malicious actor can coerce this server to hang on one of the recv calls.
# 
# Another point of notice: this server only works for udp so if a request is to long and a client sends a request via tcp nobody will be listening.

ssock = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM) #Listen on ipv4 and ipv6
ssock.bind(("", 53)) #bind to dns port on all interfaces

while True:
	sdata, saddr = ssock.recvfrom(0xFFFF) #Recv from client calling our dns port
	if not os.fork(): #if client calls us fork and have client process handle the relaying
		sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) #
		sock.sendto(sdata, ("1.1.1.1", 53))
		data, addr = sock.recvfrom(0xFFFF)
		ssock.sendto(data, saddr)