This library is basically an alternative to pyroute2, only much more rudimentary, but also significantly faster.
The problem with pure Python impementation of netlink "dump" operations is that on a system with many kernel objects in the dump (such as routes, or neighbour cache elements), parsing all the messages in the dump becomes quite expensive.
Our answer to this challenge is to not parse elements of the messages that we don't need.
The high level, user visible, API should be considered a work in progress. Just the functions that were needed for a particular bigger project are implemented. Whereas the low level API is where the speed magic comes to life.
The idea is to allow a user-supplied collector function run over each of the TLAs of the message and update an accumulator object on the way. TLAs that the user don't need will be jumped over without parsing them. Nested TLAs will be descended into only if the collector function decides that it is necessary (and supplies a new collector function for the nested elements).
User visible API and examples of "collector functions" reside in the "glue"
module, __init__.py. Low level parser infrastructure - in the core.py
module.
This package includes a builder helper in mknetlinkdefs: a program that
partially parses netlink related header files from Linux kernel and coverts
structs, enums and defines into variable and class definitions in a
generated Python module. This allows us to use the same names that are used
in the C code that deals with netlink objects. The process is somewhat flaky,
but mostly works.
The program is usually run by setup.py but can be manually initiated via
the Makefile in mknetlinkdefs.
Unfortunately, kernel code does not contain information about the type of NLA values of netlink messages. Dealing with the interpretation of the byte values of NLAs has to be left to be hardcoded in the high level API functions (or suppled by the end user).
TBD. Refer to the code in the __init__.py module in the meantime.