Network Subnet Tool

import sys
import socket
from socket import inet_aton
from netaddr import *

class SubnetTools:
    def __init__(self):
        self.INVALID = -1

    def getBitMask(self,netmask):
        b = ''
        for octal in netmask:
            b += bin(int(octal))[2:].zfill(8)
        return str(len(b.rstrip('0')))

    def validateIP(self,ip):
        try:
            inet_aton(ip)
        except:
            return False

        return True

    def createCIDR(self,ipaddr,netmask):
        if(self.validateIP(ipaddr) and self.validateIP(netmask) ):
            ipArray = ipaddr.split('.')
            netArray = netmask.split('.')

            # calculate network start
            net_start = [str(int(ipArray[x]) & int(netArray[x])) for x in range(0,4)]

            # print CIDR notation
            CIDR_address = '.'.join(net_start) + '/' + self.getBitMask(netArray)
            return (CIDR_address)
        else:
            return(self.INVALID)

    def isIPinNetwork(self,ip,cidr):
        set = IPSet([cidr])
        return (ip in set)

    def ipListMatchNetwork(self,iplist,network):
        match_list = []
        for ip in iplist:
            if(self.isIPinNetwork(ip,network)):
                match_list.append(ip)
        return match_list

    '''
    convertCIDRtoNetmask() and CIDR2MASK() do the exact same thing -- just two examples
    '''
    def convertCIDRtoNetmask(self,CIDR_address):
        mask = IPNetwork(CIDR_address)
        return mask.netmask

    def CIDR2MASK(self,CIDR_address):
        (ip,bits) = CIDR_address.split('/')
        cbits = int(bits)
        mask = []
        if (not isinstance(cbits, int) or cbits < 0 or cbits > 32):
            print ("Error: %s (which is a %s)" % (str(cbits), type(cbits).__name__))
            return None

        for t in range(4):
            if cbits > 7:
                mask.append('255')
            else:
                dec = 255 - (2**(8 - cbits) - 1)
                mask.append(str(dec))

            cbits -= 8
            if cbits < 0:
                cbits = 0

        return '.'.join(mask)

stool = SubnetTools()
ipV4Address = "10.2.10.14"
ipV4Netmask = "255.255.255.248"

cidr = stool.createCIDR(ipV4Address,ipV4Netmask)

print("IP: %s" % ipV4Address)
print("MASK: %s" % ipV4Netmask)
print("CIDR: %s" % cidr)

print("CIDR: %s is MASK: %s" % (cidr,stool.convertCIDRtoNetmask(cidr) ))
print("CIDR: %s is MASK: %s [longhand]" % (cidr,stool.CIDR2MASK(cidr) ))

'''
Basic use of isIPinNetwork()

'''
FirstIPToCheck = "10.2.10.15"
print("%s is in %s: %s" % (FirstIPToCheck,cidr,stool.isIPinNetwork(FirstIPToCheck,cidr)))

SecondIPToCheck = "10.2.10.22"
print("%s is in %s: %s" % (SecondIPToCheck,cidr,stool.isIPinNetwork(SecondIPToCheck,cidr)))

'''
Advanced use of isIPinNetwork()using ipListMatchNetwork()

Pass an array of IP addresses to test and get back a list of only
the IP addresses that are in the requested network subnet
'''
testIPs = ['10.2.10.15','10.2.10.14','10.2.10.11','10.2.10.22']
subnetIPs = stool.ipListMatchNetwork(testIPs,cidr)
print("Check the following list of IPs: %s" % testIPs)
print("These IPs were in %s:\n\t%s" % (cidr,subnetIPs))

# Example of all masks with a dummy ip
#for len in range(32,-1,-1):
#   checkcidr = ("%s/%s") % ("0.0.0.0",len)
#   print ("/%d = %s" % (len, stool.CIDR2MASK(checkcidr)))