Understanding freeradius

[RODOLPHE ANTONIO DE ARAUJO MARQUES]

Hi,
I'm currently developing a new 802.11 authentication and 
association
protocol to achieve fast handovers in 802.11 
infrastructured networks.
I need to add a new module to freeradius to manage new 
keys that will be
derived during the initial 802.1X authentication.

What I need from freeradius is to add new attributes in 
the
Access-Request and Access-Accept messages and save some 
data in a new
structure for each user.

I've been looking at the code, and reading the wiki trying 
to understand
how freeradius work, but  with no success.

Can anyone help me getting started by pointing some 
functions where the
freeradius reads and constructs messages, sends and 
receive and how it
choses the authentication method, or any other useful 
information that
may help me achieve my goal?

I'm currently using freeradius-server-2.1.1

Thank you
Rodolphe Marques