Intro
Previously I wrote a Python script that allows you to change the MAC address of an interface on a linux machine.
Improvements
Create a function that can read and print the MAC address of the interface.
Create an IF statement that compares the previous MAC address and then compares it to the changed address to determine if it has changed.
What Was Learnt?
- Using re.search to search for patterns and strings.
This was used to search for the MAC Address within the ifconfig command and passes to a variable.
To better work out what regex (regular expression) is needed use the following website
Proof of Concept
Initial Code
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#!/usr/bin/env python
import subprocess
import optparse
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 address, use --help for more info.")
return options
def change_mac(interface, new_mac):
print("[+] Changing MAC Address for " + interface + " to " + new_mac)
subprocess.call(["ifconfig", interface, "down"])
subprocess.call(["ifconfig", interface, "hw", "ether", new_mac])
subprocess.call(["ifconfig", interface, "up"])
options = get_arguments()
change_mac(options.interface, options.new_mac)
Revised Code
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#!/usr/bin/env python
import re
import subprocess
import optparse
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 address, use --help for more info.")
return options
def change_mac(interface, new_mac):
print("[+] Changing MAC Address for " + interface + " to " + new_mac)
subprocess.call(["ifconfig", interface, "down"])
subprocess.call(["ifconfig", interface, "hw", "ether", new_mac])
subprocess.call(["ifconfig", interface, "up"])
def get_current_mac(interface):
ifconfig_result = subprocess.check_output(["ifconfig", interface])
mac_address_search_result = re.search(r"\w\w:\w\w:\w\w:\w\w:\w\w:\w\w", str(ifconfig_result))
if mac_address_search_result:
return mac_address_search_result.group(0)
else:
print("[-] Could not read MAC address")
options = get_arguments()
current_mac = get_current_mac(options.interface)
print("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("[+] MAC address was successfully changed to " + current_mac)
else:
print("[-] MAC address did not get changed.")
Testing Code
