spoofmac.py

#!/usr/bin/env python3

"""Spoof MAC

Spoofing a MAC address with Python

Usage: $ python3 spoofmac.py
"""

import argparse
import os
import random
import re
import subprocess
import sys
import time


def is_root() -> bool:
    """Checks if root user

    Returns:
        bool: True if root else False
    """
    return os.geteuid() == 0


def get_rand() -> str:
    """Gets random valid MAC char

    Returns:
        str: A single char
    """
    return random.choice("abcdef0123456789")


def new_mac() -> str:
    """Creates a new MAC address

    Returns:
        str: A complete valid MAC string
    """
    return ":".join(get_rand() + get_rand() for _ in range(6))


def get_mac(interface: str) -> str:
    """Gets the MAC address

    Args:
        interface (str): The ethernet interface to get

    Returns:
        str: A complete valid MAC string
    """
    output = subprocess.check_output(["ifconfig", interface])
    mac = re.findall("([0-9a-f]{2}(?::[0-9a-f]{2}){5})", str(output))[0]
    return mac


def change_mac(mac: str, interface: str) -> None:
    """Creates a new MAC address and changes it using subprocess

    Args:
        mac (str): A provided MAC address
        interface (str): The ethernet interface to change
    """
    subprocess.call(["sudo", "ifconfig", interface, "down"])
    subprocess.call(["sudo", "ifconfig", interface, "hw", "ether", mac])
    subprocess.call(["sudo", "ifconfig", interface, "up"])


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Create a new MAC address")
    parser.add_argument("-i", "--interface", help="name of the interface")
    args = parser.parse_args()
    if not is_root():
        print('Must be <root> to run, please try using "sudo python3"...')
        sys.exit(1)
    interface = args.interface if args.interface else "eth0"
    current_mac = get_mac(interface)
    print(f"Current MAC: {current_mac}")
    try:
        while True:
            mac = new_mac()
            change_mac(mac, interface)
            summary = subprocess.check_output(["ifconfig", interface])
            if mac in str(summary):
                print(f"New MAC: {get_mac(interface)}")
                break
            time.sleep(10)
    except KeyboardInterrupt:
        change_mac("00:0c:29:8d:a2:64", interface)
        print("Interrupt detected, exiting...")
        print(f"Changing to original MAC: {get_mac(interface)}")