IPv6 UDP Sockets with Python 3

1-minute read
quick-tip
python • networking

Today I wanted to trace the syscalls that are made when using an IPv6 UDP socket. This is one of the reasons I love Python because it enables me to quickly write and test code.

I thought this might be useful for some of you:

udp_ipv6_client.py

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#!/usr/bin/env python3

import socket

UDP_IP = "::1"  # localhost
UDP_PORT = 5005
MESSAGE = "Hello, World!"

print("UDP target IP:", UDP_IP)
print("UDP target port:", UDP_PORT)
print("message:", MESSAGE)

sock = socket.socket(socket.AF_INET6, # Internet
                        socket.SOCK_DGRAM) # UDP
sock.sendto(MESSAGE.encode("UTF-8"), (UDP_IP, UDP_PORT))

udp_ipv6_server.py

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#!/usr/bin/env python3

import socket

UDP_IP = "::" # = 0.0.0.0 u IPv4
UDP_PORT = 5005

sock = socket.socket(socket.AF_INET6, # Internet
                        socket.SOCK_DGRAM) # UDP
sock.bind((UDP_IP, UDP_PORT))

while True:
    data, addr = sock.recvfrom(1024) # buffer size is 1024 bytes
	print("received message:", data.decode("UTF-8"))

The code is based on this GitHub gist by tuxmartin. I just made some changes to run it with Python 3.