change-mac.py

import subprocess
import optparse 
import re

# get arguments from user input
def get_arguments():
    parser = optparse.OptionParser()

    parser.add_option("-i", "--interface", dest="interface", help="Interface to change its MAC address")
    parser.add_option("-m", "--mac", dest="new_mac", help="New MAC address")
    (options, arguments) = parser.parse_args()
    
    if not options.interface:
        parser.error("[-] Please specify an interface, use --help for more info.")
    elif not options.new_mac:
        parser.error("[-] Please specify a new mac, use --help for more info.")
    return options 

# function need an interface and a mac address as arguments
def change_mac(interface, new_mac):
    print(f"\n[+] Changing MAC address for {interface}...")
    subprocess.call(["ifconfig", interface, "down"])
    subprocess.call(["ifconfig", interface, "hw", "ether", new_mac])
    subprocess.call(["ifconfig", interface, "up"])

# get current mac from ifconfig output
def get_current_mac(interface):
    ifconfig_result = subprocess.check_output(["ifconfig", interface]).decode('utf-8')

    mac_result = re.search(r"\w\w:\w\w:\w\w:\w\w:\w\w:\w\w", ifconfig_result)

    if mac_result:
        return mac_result.group(0)
    else:
        print("[-] Error. Could not read mac address.")


options = get_arguments()
current_mac = get_current_mac(options.interface)
print(f"Current MAC = {str(current_mac)}")

change_mac(options.interface, options.new_mac)

current_mac = get_current_mac(options.interface)
if current_mac == options.new_mac:
    print(f"MAC address was successfully changed to {options.new_mac}")
else:
    print("MAC address did not get changed!")