IPy 1.01

Presentation of the API

The IP class allows a comfortable parsing and handling for most notations in use for IPv4 and IPv6 addresses and networks. It was greatly inspired by RIPE’s Perl module NET::IP’s interface but doesn’t share the implementation. It doesn’t share non-CIDR netmasks, so funky stuff like a netmask of 0xffffff0f can’t be done here.

>>> from IPy import IP
>>> ip = IP('127.0.0.0/30')
>>> for x in ip:
...  print(x)
...
127.0.0.0
127.0.0.1
127.0.0.2
127.0.0.3
>>> ip2 = IP('0x7f000000/30')
>>> ip == ip2
1
>>> ip.reverseNames()
['0.0.0.127.in-addr.arpa.', '1.0.0.127.in-addr.arpa.', '2.0.0.127.in-addr.arpa.', '3.0.0.127.in-addr.arpa.']
>>> ip.reverseName()
'0-3.0.0.127.in-addr.arpa.'
>>> ip.iptype()
'LOOPBACK'

Supports most IP address formats

It can detect about a dozen different ways of expressing IP addresses and networks, parse them and distinguish between IPv4 and IPv6 addresses:

>>> IP('10.0.0.0/8').version()
4
>>> IP('::1').version()
6

>>> print(IP(0x7f000001))
127.0.0.1
>>> print(IP('0x7f000001'))
127.0.0.1
>>> print(IP('127.0.0.1'))
127.0.0.1
>>> print(IP('10'))
10.0.0.0

>>> print(IP('1080:0:0:0:8:800:200C:417A'))
1080::8:800:200c:417a
>>> print(IP('1080::8:800:200C:417A'))
1080::8:800:200c:417a
>>> print(IP('::1'))
::1
>>> print(IP('::13.1.68.3'))
::d01:4403

>>> print(IP('127.0.0.0/8'))
127.0.0.0/8
>>> print(IP('127.0.0.0/255.0.0.0'))
127.0.0.0/8
>>> print(IP('127.0.0.0-127.255.255.255'))
127.0.0.0/8

Derive network address

IPy can transform an IP address into a network address by applying the given netmask:

>>> print(IP('127.0.0.1/255.0.0.0', make_net=True))
127.0.0.0/8

This can also be done for existing IP instances:

>>> print(IP('127.0.0.1').make_net('255.0.0.0'))
127.0.0.0/8

Convert address to string

Nearly all class methods which return a string have an optional parameter ‘wantprefixlen’ which controls if the prefixlen or netmask is printed. Per default the prefilen is always shown if the network contains more than one address:

wantprefixlen == 0 / None     don't return anything   1.2.3.0
wantprefixlen == 1            /prefix                 1.2.3.0/24
wantprefixlen == 2            /netmask                1.2.3.0/255.255.255.0
wantprefixlen == 3            -lastip                 1.2.3.0-1.2.3.255

You can also change the defaults on an per-object basis by fiddling with the class members:

• NoPrefixForSingleIp

• WantPrefixLen

Examples of string conversions:

>>> IP('10.0.0.0/32').strNormal()
'10.0.0.0'
>>> IP('10.0.0.0/24').strNormal()
'10.0.0.0/24'
>>> IP('10.0.0.0/24').strNormal(0)
'10.0.0.0'
>>> IP('10.0.0.0/24').strNormal(1)
'10.0.0.0/24'
>>> IP('10.0.0.0/24').strNormal(2)
'10.0.0.0/255.255.255.0'
>>> IP('10.0.0.0/24').strNormal(3)
'10.0.0.0-10.0.0.255'
>>> ip = IP('10.0.0.0')
>>> print(ip)
10.0.0.0
>>> ip.NoPrefixForSingleIp = None
>>> print(ip)
10.0.0.0/32
>>> ip.WantPrefixLen = 3
>>> print(ip)
10.0.0.0-10.0.0.0

Work with multiple networks

Simple addition of neighboring netblocks that can be aggregated will yield a parent network of both, but more complex range mapping and aggregation requires is available with the IPSet class which will hold any number of unique address ranges and will aggregate overlapping ranges.

>>> from IPy import IP, IPSet
>>> IP('10.0.0.0/22') - IP('10.0.2.0/24')
IPSet([IP('10.0.0.0/23'), IP('10.0.3.0/24')])
>>> IPSet([IP('10.0.0.0/23'), IP('10.0.3.0/24'), IP('10.0.2.0/24')])
IPSet([IP('10.0.0.0/22')])
>>> s = IPSet([IP('10.0.0.0/22')])
>>> s.add(IP('192.168.1.0/29'))
>>> s
IPSet([IP('10.0.0.0/22'), IP('192.168.1.0/29')])
>>> s.discard(IP('192.168.1.2'))
>>> s
IPSet([IP('10.0.0.0/22'), IP('192.168.1.0/31'), IP('192.168.1.3'), IP('192.168.1.4/30')])

IPSet supports the set method isdisjoint:

>>> s.isdisjoint(IPSet([IP('192.168.0.0/16')]))
False
>>> s.isdisjoint(IPSet([IP('172.16.0.0/12')]))
True

IPSet supports intersection:

>>> s & IPSet([IP('10.0.0.0/8')])
IPSet([IP('10.0.0.0/22')])

Compatibility and links

IPy 1.01 works on Python version 2.6 - 3.7.

The IP module should work in Python 2.5 as long as the subtraction operation is not used. IPSet requires features of the collecitons class which appear in Python 2.6, though they can be backported.

Eratta

When using IPv6 addresses, it is best to compare using IP().len() instead of len(IP). Addresses with an integer value > 64 bits can break the 2nd method. See http://stackoverflow.com/questions/15650878 for more info.

Fuzz testing for IPSet will throw spurious errors when the IPSet module combines two smaller prefixes into a larger prefix that matches the random prefix tested against.

This Python module is under BSD license: see COPYING file.

Further Information might be available at: https://github.com/autocracy/python-ipy