Python - Generate a list of IP addresses from user input

Question

I am trying to create a script that generates a list of IP addresses based on a users input for a start and end IP range. For example, they could enter 192.168.1.25 & 1

Answer 1

It'd be easier to use a format like nmap's:

192.168.1.1-255

As now, you can do:

octets = '192.168.1.1-255'.split('.')
parsed_ranges = [map(int, octet.split('-')) for octet in octets]

parsed_ranges will look like [[192], [168], [1], [1, 255]]. From there, generating the addresses is simple with itertools:

import itertools

ranges = [range(r[0], r[1] + 1) if len(r) == 2 else r for r in parsed_ranges]
addresses = itertools.product(*ranges)

Here's a simple implementation:

import itertools

def ip_range(input_string):
    octets = input_string.split('.')
    chunks = [map(int, octet.split('-')) for octet in octets]
    ranges = [range(c[0], c[1] + 1) if len(c) == 2 else c for c in chunks]

    for address in itertools.product(*ranges):
        yield '.'.join(map(str, address))

And the result:

>>> for address in ip_range('192.168.1-2.1-12'):  print(address)
192.168.1.1
192.168.1.2
192.168.1.3
192.168.1.4
192.168.1.5
192.168.1.6
192.168.1.7
192.168.1.8
192.168.1.9
192.168.1.10
192.168.1.11
192.168.1.12
192.168.2.1
192.168.2.2
192.168.2.3
192.168.2.4
192.168.2.5
192.168.2.6
192.168.2.7
192.168.2.8
192.168.2.9
192.168.2.10
192.168.2.11
192.168.2.12

Answer 2

Remember that a dotted IPv4-address "x.x.x.x" is nothing more than a human-readable representation of a 32-bit integer. Using this, you can generate the ranges like this:

def undotIPv4 (dotted):
    return sum (int (octet) << ( (3 - i) << 3) for i, octet in enumerate (dotted.split ('.') ) )

def dotIPv4 (addr):
    return '.'.join (str (addr >> off & 0xff) for off in (24, 16, 8, 0) )

def rangeIPv4 (start, stop):
    for addr in range (undotIPv4 (start), undotIPv4 (stop) ):
        yield dotIPv4 (addr)

for x in rangeIPv4 ('1.2.3.4', '1.2.4.22'):
    print (x)