Convert CIDR networks into string glob (like what ssh_config expects)

cidr2glob.py

#!/usr/bin/env python2.7
from netaddr import *
import re
import pprint

def cidr2glob(cidr):
    network = IPNetwork(cidr)

    if network.prefixlen <= 16:
        return map(lambda subnet: re.sub(r'\.0\.0$', '.*', str(subnet.ip)), network.subnet(16))
    elif network.prefixlen <= 24:
        return map(lambda subnet: re.sub(r'\.0$', '.*', str(subnet.ip)), network.subnet(24))
    else:
        return map(lambda ip: str(ip), list(network))



for net in ['10.255.0.0/11', '10.255.102.0/22', '10.255.103.0/24', '10.255.102.2/28']:
    print net
    pprint.pprint(cidr2glob(net))
    print "\n\n"

Output

10.255.0.0/11
['10.224.*',
 '10.225.*',
 '10.226.*',
 '10.227.*',
 '10.228.*',
 '10.229.*',
 '10.230.*',
 '10.231.*',
 '10.232.*',
 '10.233.*',
 '10.234.*',
 '10.235.*',
 '10.236.*',
 '10.237.*',
 '10.238.*',
 '10.239.*',
 '10.240.*',
 '10.241.*',
 '10.242.*',
 '10.243.*',
 '10.244.*',
 '10.245.*',
 '10.246.*',
 '10.247.*',
 '10.248.*',
 '10.249.*',
 '10.250.*',
 '10.251.*',
 '10.252.*',
 '10.253.*',
 '10.254.*',
 '10.255.*']



10.255.102.0/22
['10.255.100.*', '10.255.101.*', '10.255.102.*', '10.255.103.*']



10.255.103.0/24
['10.255.103.*']



10.255.102.2/28
['10.255.102.0',
 '10.255.102.1',
 '10.255.102.2',
 '10.255.102.3',
 '10.255.102.4',
 '10.255.102.5',
 '10.255.102.6',
 '10.255.102.7',
 '10.255.102.8',
 '10.255.102.9',
 '10.255.102.10',
 '10.255.102.11',
 '10.255.102.12',
 '10.255.102.13',
 '10.255.102.14',
 '10.255.102.15']