Conversion from IP string to integer, and backward in Python

Question

i have a little problem with my script, where i need to convert ip in form \'xxx.xxx.xxx.xxx\' to integer representation and go back from this form.

def ipto         


        

Answer 1

Python 3 has ipaddress module which features very simple conversion:

int(ipaddress.IPv4Address("192.168.0.1"))
str(ipaddress.IPv4Address(3232235521))

Answer 2

Below are the fastest and most straightforward (to the best of my knowledge) convertors for IPv4 and IPv6:

    try:
        _str = socket.inet_pton(socket.AF_INET, val)
    except socket.error:
        raise ValueError
    return struct.unpack('!I', _str)[0]
    -------------------------------------------------
    return socket.inet_ntop(socket.AF_INET, struct.pack('!I', n))
    -------------------------------------------------
    try:
        _str = socket.inet_pton(socket.AF_INET6, val)
    except socket.error:
        raise ValueError
    a, b = struct.unpack('!2Q', _str)
    return (a << 64) | b
    -------------------------------------------------
    a = n >> 64
    b = n & ((1 << 64) - 1)
    return socket.inet_ntop(socket.AF_INET6, struct.pack('!2Q', a, b))

Python code not using inet_ntop() and struct module is like order of magnitude slower than this regardless of what it is doing.

Answer 3

One line

reduce(lambda out, x: (out << 8) + int(x), '127.0.0.1'.split('.'), 0)

Answer 4

#!/usr/bin/env python
import socket
import struct


def ip2int(addr):
    return struct.unpack("!I", socket.inet_aton(addr))[0]


def int2ip(addr):
    return socket.inet_ntoa(struct.pack("!I", addr))


print(int2ip(0xc0a80164)) # 192.168.1.100
print(ip2int('10.0.0.1')) # 167772161

Answer 5

You lose the left-zero-padding which breaks decoding of your string.

Here's a working function:

def inttoip(ip):
    return socket.inet_ntoa(hex(ip)[2:].zfill(8).decode('hex'))