EAP peer implementation from wpa_supplicant as a library

[Jouni Malinen]

On Wed, Oct 17, 2007 at 08:53:00AM +0200, Stjepan Gros wrote:

> This is a good question. I was planning to raise similar question also,
> but due to the lack of time wasn't able to do so. So, I'll do that now.

Sorry about this taking a while, but I finally had chance to take a
closer look at this thread..

> We use supplicant part as a library in IKEv2 protocol implementation.
> More specifically, version 0.4.7. Makefiles that produce dynamic
> libraries can be found in the contrib/ subdirectory of the ikev2
> (ikev2.sourceforge.net) source as well as README file that details how
> to build libraries.

To be more exact, you are using EAP peer functionality, not the IEEE
802.1X/EAPOL supplicant, from wpa_supplicant.

> The exact content of the Makefiles was trial and error process. But
> eventually, it worked. The main problem are some auxiliary functions,
> e.g. logging, that are mixed with other functions and so are not easily
> replaceable with ikev2's equivalents. This is necessary in order to
> better integrate the supplicant code into ikev2 implementation.

Even though there are still quite many areas that can be improved, this
should be much better in the current wpa_supplicant 0.6.x code base. The
logging functions that you may want to replace are in their own file
(src/utils/wpa_debug.c) and you can link in other files without having
to replace some of the common helper functions.

In addition, I just added a simple example program that shows how to
interact with the EAP peer and EAP server code. The Makefile for this
program shows how to build a library with EAP functionality and the
example program is linked against that library. I would expect this to
be quite close to the needs of your IKEv2 implementation.

The example code is available from my Git repository at http://w1.fi/ in
a new top level directory, eap_example. This makes it easier for me to
find areas in the interface between EAP and EAPOL (or other protocol
using EAP) and I would expect that some of the interfaces will change
during 0.6.x development to clear these, so please do not expect the
interfaces to be fixed at this point.

-- 
Jouni Malinen                                            PGP id EFC895FA