Python script to change MAC address of Linux machine

What is MAC Address: In a computer network, the MAC Address is used at the lowest networking level, where network interfaces communicate with one another. See details here.

Need of changing MAC Address:

• To bypass MAC Address filtering
• To bypass certain kind of MITM spoofing attack
• To avoid device tracking in a public network

There are many other tasks like becoming anonymous in a network and to avoid some network attacks where changing MAC Address becomes useful.

Changing MAC Address in Linux Machine: In Linux, a simple way to change MAC address is by using ifconfig command.
If it is not already installed, we can install it using:

sudo apt-get update
sudo apt-get install ifconfig

After installing this package, we can change the MAC Address using:

sudo ifconfig <interface-name> down
sudo ifconfig <interface-name> hw ether <new-mac-address> 
sudo ifconfig <interface-name> up

We can see the list of interfaces using:

ifconfig

Automation using Python: Since it is not possible for us to manually change the MAC Address every time, we can automate the process of changing the MAC Address using Python. This script will keep changing the MAC Address in a constant period of time.
Below is the implementation of above idea.

# Python Script to change MAC Address

# Import Useful modules
import sys
import subprocess
import argparse
import random
import time
import re


# Function to get the interface name
def get_arguments():
    # This will give user a neat CLI
    parser = argparse.ArgumentParser()
    # We need the interface name
    parser.add_argument("-i", "--interface",
                dest="interface",
                help="Name of the interface. "
                "Type ifconfig for more details.")
    options = parser.parse_args()
    # Check if interface was given
    if options.interface:
        return options.interface
    else:
        parser.error("[!] Invalid Syntax. "
                     "Use --help for more details.")


# Function to change the MAC Address
def change_mac(interface, new_mac_address):
    # As explained above, these lines will
    # execute these commands for us
    subprocess.call(["sudo", "ifconfig", interface,
                     "down"])
    subprocess.call(["sudo", "ifconfig", interface,
                     "hw", "ether", new_mac_address])
    subprocess.call(["sudo", "ifconfig", interface,
                     "up"])

# Function to generate a random MAC Address
def get_random_mac_address():
    characters = "0123456789abcdef"
    random_mac_address = "00"
    for i in range(5):
        random_mac_address += ":" + \
                        random.choice(characters) \
                        + random.choice(characters)
    return random_mac_address

# Function to get the current MAC Address
# We will use it restore MAC address
# in case something goes wrong.
def get_current_mac(interface):
    output = subprocess.check_output(["ifconfig",
                                      interface])
    return re.search("\w\w:\w\w:\w\w:\w\w:\w\w:\w\w",
                  str(output)).group(0)

# Driver Program
if __name__ == "__main__":
    print("[* Welcome to MAC ADDRESS Changer *]")
    print("[*] Press CTRL-C to QUIT")
    # Change it to required value(in sec)
    TIME_TO_WAIT = 60
    interface = get_arguments()
    current_mac = get_current_mac(interface)
    try:
        while True:
            random_mac = get_random_mac_address()
            change_mac(interface, random_mac)
            new_mac_summary = subprocess.check_output(
                ["ifconfig", interface])
            if random_mac in str(new_mac_summary):
                print("\r[*] MAC Address Changed to",
                      random_mac,
                      end=" ")
                sys.stdout.flush()
            # Wait for a constant period of time
            time.sleep(TIME_TO_WAIT)

    except KeyboardInterrupt:
        # Restore the MAC before quitting.
        change_mac(interface, current_mac)
        print("\n[+] Quitting Program...")

Output: