Takes a list of CIDR formatted IP's and outputs the network & broadcast address in decimal format - handy to do arithmetic based queries in a database.

ip_decimal.py

#!/usr/bin/env python2

import sys
import csv
import ipaddr # via code.google.com/p/ipaddr-py/

# Reads a file of ip's and spits out decimal start/end points
#     http://ipinfodb.com/ip_database.php
# Then load into mysql and select the country you fancy into a file:
# SELECT ip_cidr, country_code FROM ip_group_country WHERE country_code IN ("IT", "DE") INTO OUTFILE '/tmp/eu-ips.txt';

# The output can go into a table like this:
#
# CREATE TABLE iplookup (
#    id MEDIUMINT NOT NULL AUTO_INCREMENT,
#    network_address VARCHAR(15) NOT NULL,
#    broadcast_address VARCHAR(15) NOT NULL,
#    network_decimal INTEGER NOT NULL,
#    broadcast_decimal INTEGER NOT NULL,
#    country_code VARCHAR(2) NOT NULL,
#    PRIMARY KEY(id)
# ) ENGINE MyISAM;
#
# Then you need to load it in via your output csv:
#
# LOAD DATA INFILE '/tmp/out.csv' INTO TABLE iplookup FIELDS TERMINATED BY ','
# ENCLOSED BY '"' LINES TERMINATED BY '\r\n'
# (network_address, broadcast_address, network_decimal, broadcast_decimal, country_code);
#
# Now query!

MULTS = [256**3, 256**2, 256, 1] # For decimal conversion - each chunk of the ip4 addy

def to_decimal(addr):
    """ Converts an input (string) ipv address to decimal equivilant for
        easier arthemtic in the database """
    decimal_ip = 0
    parts = enumerate(str(addr).split('.'))
    for (index, part) in parts:
        decimal_ip += int(part)*MULTS[index]
    return decimal_ip

def processInput():
    """ Read in and process our list of ips """
    input_file = open(sys.argv[1])
    output_file = csv.writer(open(sys.argv[2], 'w+'), quotechar='"', \
        quoting=csv.QUOTE_ALL)
    for line in input_file:
        line = line.split('\t')
        network = ipaddr.IPNetwork(line[0])
        c_code = line[1].strip()
        network_iter = network.iterhosts()
        output_file.writerow([str(network.network), str(network.broadcast), \
            to_decimal(network.network), to_decimal(network.broadcast), c_code])
        
if __name__ == '__main__':
    processInput()