how to find all ip addresses between 2 ip addresses

Question

Can anyone think of an algorithm to put all of the addresses between two others and put them in a list (using python)? For example:

findIPs('111.111.111.0', '111.111.111.3')

Should return ('111.111.111.0', '111.111.111.1', '111.111.111.2', '111.111.111.3'). My main problem arises from when corresponding blocks are identical otherwise I could just use nested for loops with the range function.

Can you post the code you have so far? – debianplebian Jun 20 '13 at 17:46 — debianplebian, Jun 20 '13 at 17:46

falsetru · Accepted Answer · 2013-06-20T17:53:10.590

12

Python 3.3 with standard library ipaddress module / Python 3.2-, Python 2.x with ipaddr

try:
    from ipaddress import ip_address
except ImportError:
    from ipaddr import IPAddress as ip_address

def findIPs(start, end):
    start = ip_address(start)
    end = ip_address(end)
    result = []
    while start <= end:
        result.append(str(start))
        start += 1
    return result

print(findIPs('111.111.111.0', '111.111.111.3'))

Python 3.2-, Python 2.x

import struct
import socket

def findIPs(start, end):
    ipstruct = struct.Struct('>I')
    start, = ipstruct.unpack(socket.inet_aton(start))
    end, = ipstruct.unpack(socket.inet_aton(end))
    return [socket.inet_ntoa(ipstruct.pack(i)) for i in range(start, end+1)]

print(findIPs('111.111.111.0', '111.111.111.3'))

edited Jun 20 '13 at 17:53

answered Jun 20 '13 at 17:47

falsetru

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how do i get the ipaddress module? it is not in the standard library and the docs says that it is in the provisional package. – avorum Jun 20 '13 at 17:53
Updated code. See ipaddr link. – falsetru Jun 20 '13 at 17:54
alright got this to work, thanks for your help. – avorum Jun 20 '13 at 18:23

score 1 · Answer 2 · answered Jun 20 '13 at 17:53

Here is one pretty straightforward approach:

def ip_to_int(ip):
    val = 0
    for i, s in enumerate(ip.split('.')):
        val += int(s) * 256 ** (3 - i)
    return val

def int_to_ip(val):
    octets = []
    for i in range(4):
        octets.append(str(val % 256))
        val = val >> 8
    return '.'.join(reversed(octets))

def findIPs(start, end):
    for i in range(ip_to_int(start), ip_to_int(end) + 1):
        yield int_to_ip(i)

Examples:

>>> list(findIPs('111.111.111.0', '111.111.111.3'))
['111.111.111.0', '111.111.111.1', '111.111.111.2', '111.111.111.3']
>>> list(findIPs('111.111.111.254', '111.111.112.1'))
['111.111.111.254', '111.111.111.255', '111.111.112.0', '111.111.112.1']

@avorum I only answered this way because I didn't realize there was a module for this, I would recommend using falsetru's answer. — Andrew Clark, Jun 20 '13 at 18:08

score 0 · Answer 3 · answered Jun 20 '13 at 17:53

A little searching would have probably found the answer as well, but this should work:

import socket
import struct

ip_to_number = lambda ip: struct.unpack('!I', socket.inet_aton(ip))[0]
number_to_ip = lambda num: socket.inet_ntoa(struct.pack('!I', num))

def ip_range(a, b):
    a = ip_to_number(a)
    b = ip_to_number(b)

   for i in range(a, b+1):
     yield number_to_ip(i)

how to find all ip addresses between 2 ip addresses

3 Answers3

Python 3.3 with standard library ipaddress module / Python 3.2-, Python 2.x with ipaddr

Python 3.2-, Python 2.x