netlink: traffic control and NETLINK_FIREWALL sockets

hi, i have recently been doing a lot of research and hacking around with
netlink. i say "research" b/c there seems to be little or no
documentation or examples of netlink use. i have of course studied the
kernel source and the GNU zebra program and libnetlink. with the help
of them and alot of trial and error i have learned alot of cool stuff i
must say. currently im working a thorough tutorial so that others might
find it easier to learn this stuff. anyways, my problem now is this:
i am very interested in learning about the traffic control portion of
netlink as well as the use of _FIREWALL sockets. i have of course read
the new RFC(3549) published in july, but as it says "this is not
intended to be a tutorial on netlink." from the rfc i have gotten the
general idea of the traffic control commands, but nowhere near enuf info
to understand how they work. i figure there MUST be some person who has
already gone down this path, but for the life of me i can find NO code
anywhere using traffic control messages or a NETLINK_FIREWALL type
socket with the exception of ip-route program which uses traffic control.

i am reading the ip-route2 source code to try and figure out the traffic
control stuff, but i still can't find anything for FIREWALL sockets.
any ideas?

-sean