eap_example/README

EAP peer/server library and example program
Copyright (c) 2007, Jouni Malinen <j@w1.fi>

This software may be distributed under the terms of the BSD license.
See the parent directory README for more details.


The interfaces of the EAP server/peer implementation are based on RFC
4137 (EAP State Machines). This RFC is coordinated with the state
machines defined in IEEE 802.1X-2004. hostapd and wpa_supplicant
include implementation of the IEEE 802.1X EAPOL state machines and the
interface between them and EAP. However, the EAP implementation can be
used with other protocols, too, by providing a compatible interface
which maps the EAPOL<->EAP variables to another protocol.

This directory contains an example showing how EAP peer and server
code from wpa_supplicant and hostapd can be used as a library. The
example program initializes both an EAP server and an EAP peer
entities and then runs through an EAP-PEAP/MSCHAPv2 authentication.

eap_example_peer.c shows the initialization and glue code needed to
control the EAP peer implementation. eap_example_server.c does the
same for EAP server. eap_example.c is an example that ties in both the
EAP server and client parts to allow an EAP authentication to be
shown.

In this example, the EAP messages are passed between the server and
the peer are passed by direct function calls within the same process.
In practice, server and peer functionalities would likely reside in
separate devices and the EAP messages would be transmitted between the
devices based on an external protocol. For example, in IEEE 802.11
uses IEEE 802.1X EAPOL state machines to control the transmission of
EAP messages and WiMax supports optional PMK EAP authentication
mechanism that transmits EAP messages as defined in IEEE 802.16e.


The EAP library links in number of helper functions from src/utils and
src/crypto directories. Most of these are suitable as-is, but it may
be desirable to replace the debug output code in src/utils/wpa_debug.c
by dropping this file from the library and re-implementing the
functions there in a way that better fits in with the main
application.