xk2600 / ipampy

ipam python module to make easy work of IP address management to include subnetting, supernetting, tracking usage, and things of the like.

IPAMpy

ipam python module to make easy work of IP address management to include subnetting, supernetting, tracking usage, and things of the like.

This is an amalgomation of a various functions I've written, rewritten, chagned, and tweaked over the years. I finally ran into a usecase where I needed to do some fairly complex things and hence condensed the working bits into this library/module. It is not complete, and should be used with that understanding.

WHY IPAMpy?

Lots of other libraries exist. But I have yet to find one that I can use arithmetic to manipulate address space. IPAMpy does just that. The following is a synopsis of how it works:

IPAM.py exports the following:

• Prefix
• IPAM

Prefix

Prefix is the base class which holds and hosts the primary functionality on which IPAMpy operates. Prefix instances really just represnt two elements at their core:

• netid-- an address-family representing a unique internetwork source or destination. (IPv4 or IPv6 address).
• masklen-- a number representing the bit boundary where the network ends and the subnetworks or hosts are allocated from.

Other attributes are tracked to enable in higher-level functions, for example:

• net-- a representation

IPAM

IPAM is a namespace containing the CidrAllocation class as well as various constants documenting address allocations and delegations to registration authorities.

• CidrAllocation-- a subclass of Prefix which implements the ability to includes a descr property allowing notation of the CidrAlloication as its created or upon creation of subnets derived from a given CidrAllocation.

• Whois-- a whois client which can lookup delegations and automatically create dependancy based CidrAllocation instances in the appropriate namespace for NET-BLOCKS assigned by the various delegated registration authorities.

• Constants:

  • CLASS-- Prefix representation of classful addressing: A, B, C, D, and E.

  • IANA-- Reservations held and managed by the Internet-Assigned Numbering Authority.

    • SPECIAL_USE-- IANA Special Use Assignments containing IETF RFC allocations such as LOCAL_IDENT, SHARED, LOOPBACK, LINK_LOCAL, TEST-NET, and BENCHMARK.

  • ARIN-- Delegated networks allocated and distributed by ARIN.

  • RIPE-- Delegated networks allocated and distributed by RIPE.

  • APNIC-- Delegated networks allocated and distributed by APNIC.

NOTES ON NET BLOCKS

NET blocks are representations of allocations within the whois database. They are formed from the name field in the output of the whois information by replacing hyphens (-) with underscores and capitalizing the text.

Blocks with a masklen set are supernets of various subnets within the originating parent supernet. Most class B and C addresing has been rulled up int supernets as /8s. This means in most cases, you use/allocate a NET-BLOCK allocation first with the correct subnetlen applied. Then when you assign segments out of this block, they'll be indexed as seen in modern whois implementations. The CLASSFUL allocations are purely here for the edge use-case that requires them.

TODO

• Change the .net proeprty from representing the ip component of the prefix to return an instance of --a subclass of Prefix. extends the functionality of for delegating iteration, subnet indexes, and arithmetic functions for interacting with prefixes (subnetting, supernetting, etc.)

• Create a .host property to delegate host based allocation (effectively an alias which makes all subnet allocations /32s)

  NOTE The above two items could possibly be written as descriptors.

• Implement Whois, replacing shell script and exec.