lanscan_arp.py

# Import scapy
import scapy.all as scapy
# We need to create regular expressions to ensure that the input is correctly formatted.
import re

# Basic user interface header
print(r"""______            _     _  ______                 _           _ 
|  _  \          (_)   | | | ___ \               | |         | |
| | | |__ ___   ___  __| | | |_/ / ___  _ __ ___ | |__   __ _| |
| | | / _` \ \ / / |/ _` | | ___ \/ _ \| '_ ` _ \| '_ \ / _` | |
| |/ / (_| |\ V /| | (_| | | |_/ / (_) | | | | | | |_) | (_| | |
|___/ \__,_| \_/ |_|\__,_| \____/ \___/|_| |_| |_|_.__/ \__,_|_|""")
print("\n****************************************************************")
print("\n* Copyright of David Bombal, 2021                              *")
print("\n* https://www.davidbombal.com                                  *")
print("\n* https://www.youtube.com/davidbombal                          *")
print("\n****************************************************************")

# Regular Expression Pattern to recognise IPv4 addresses.
ip_add_range_pattern = re.compile("^(?:[0-9]{1,3}\.){3}[0-9]{1,3}/[0-9]*$")

# Get the address range to ARP
while True:
    ip_add_range_entered = input("\nPlease enter the ip address and range that you want to send the ARP request to (ex 192.168.1.0/24): ")
    if ip_add_range_pattern.search(ip_add_range_entered):
        print(f"{ip_add_range_entered} is a valid ip address range")
        break


# Try ARPing the ip address range supplied by the user. 
# The arping() method in scapy creates a pakcet with an ARP message 
# and sends it to the broadcast mac address ff:ff:ff:ff:ff:ff.
# If a valid ip address range was supplied the program will return 
# the list of all results.
arp_result = scapy.arping(ip_add_range_entered)