
           	SIM Triplets 

INTRODUCTION

  The module rlm_sim_files reads challenges/responses for use by the
EAP-SIM method. This module is a reference implementation for what someone
might do via a database or other system.
  It provides for authorization only.

RADIUSD.CONF

  To configure this module, list is in modules.
  An optional option to set the file name exists, it otherwise defaults to
${raddbdir}/simtriplets.dat.

  e.g: in radiusd.conf, modules {},

     sim_files {
  	     simtriplets = "/some/file"
     }


  in radiusd.conf, authorize {}, add:
     sim_files 

  before eap.

SIMTRIPLETS.DAT:

  The format of the file is one triplet per line, with the userid, aka
"imsi" first. Lines starting with # are considered comments.
 
  imsi,challenge,kc,sres

  for example:

232420100000015,34000000000000000000000000000000,34112233,445566778899AABB

  Types

	imsi		- just a string
	challenge	- 16-byte value in hex.
	kc		- 4-byte value in hex, the client key (Kc)
	sres		- 8-byte value in hex, the secure response

  Note that EAP-SIM requires *three* sets of triplets, so there must be
three challenges found in the file. The first three challenges are used.
  Also note that the "0x" for hex is not required, and is illegal.
  Space and tabs are not permitted.

AUTHORIZATION
 
  Note, if the NAS continues to send the User-Name attribute in subsequent
access-requests (such as continuations of the EAP-sim protocol), then the
authorization process will be repeated.
  EAP-sim will capture the first set of attributes, so if they change, that
is okay.

  A future version of this module may look at the presence of the EAP-Identity
attribute to determine if attributes must be retrieved.
  However, in the general case, one might not know one wants to even do the
EAP-Start to ask for the identity, until one has seen the username.

  If this module is successful at retrieving three sets of triplets, then
the EAP-Type: attribute will be set to SIM. The EAP module itself will set
the Auth-Type to EAP when it sees the EAP-Message attribute.

  See rlm_eap for details about the attributes used in EAP-sim.

$Id: rlm_sim_triplets,v 1.3 2004/01/30 20:39:58 mcr Exp $





