Auth_radius Module

Jan Janak

   FhG Fokus

Juha Heinanen

   Song Networks

Stelios Sidiroglou-Douskos

Edited by

Jan Janak

   Copyright © 2002, 2003 FhG FOKUS
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   Table of Contents
   1. User's Guide

        1.1. Overview
        1.2. Dependencies
        1.3. Exported Parameters

              1.3.1. radius_config (string)
              1.3.2. service_type (integer)

        1.4. Exported Functions

              1.4.1. radius_www_authorize(realm)
              1.4.2. radius_proxy_authorize(realm)

   2. Developer's Guide
   3. Frequently Asked Questions

   List of Examples
   1-1. radius_config parameter usage
   1-2. radius_config usage
   1-3. radius_www_authorize usage
   1-4. proxy_authorize usage
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Chapter 1. User's Guide

1.1. Overview

   This module contains functions that are used to perform
   authentication using a Radius server. Basically the proxy will
   pass along the credentials to the radius server which will in
   turn send a reply containing result of the authentication. So
   basically the whole authentication is done in the Radius
   server. Before sending the request to the radius server we
   perform some sanity checks over the credentials to make sure
   that only well formed credentials will get to the server. We
   have implemented radius authentication according to
   draft-sterman-aaa-sip-00. This module requires radiusclient
   library version 0.4.1 or higher which is available from
   http://developer.berlios.de/projects/radiusclient-ng/.

   How to configure radius server -- more detailed description --
   TBD.

   Warning

   The detailed description of radius authentication setup is
   important since many people will use it and we want to make
   the setup painless.
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1.2. Dependencies

   The module depends on the following modules (in the other
   words the listed modules must be loaded before this module):

     * auth -- Generic authentication functions
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1.3. Exported Parameters

1.3.1. radius_config (string)

   This is the location of the configuration file of radius
   client libraries.

   Default value is
   "/usr/local/etc/radiusclient/radiusclient.conf".

   Example 1-1. radius_config parameter usage
modparam("auth_radius", "radius_config", "/etc/radiusclient.conf")
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1.3.2. service_type (integer)

   This is the value of the Service-Type radius attribute to be
   used. The default should be fine for most people. See your
   radius client include files for numbers to be put in this
   parameter if you need to change it.

   Default value is "15".

   Example 1-2. radius_config usage
modparam("auth_radius", "service_type", 15)
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1.4. Exported Functions

1.4.1. radius_www_authorize(realm)

   The function verifies credencials according to RFC2617. If the
   credentials are verified sucessfully then the function will
   succeed and mark the credentials as authorized (marked
   credentials can be later used by some other functions). If the
   function was unable to verify the credentials for some reason
   then it will fail and the script should call www_challenge
   which will challenge the user again.

   This function will, in fact, perform sanity checks over the
   received credentials and then pass them along to the radius
   server which will verify the credentials and return whether
   they are valid or not.

   Meaning of the parameter is as follows:

     * realm - Realm is a opaque string that the user agent
       should present to the user so he can decide what username
       and password to use. Usualy this is domain of the host the
       server is running on.
       If an empty string "" is used then the server will
       generate it from the request. In case of REGISTER requests
       To header field domain will be used (because this header
       field represents a user being registered), for all other
       messages From header field domain will be used.

   Example 1-3. radius_www_authorize usage
...
if (radius_www_authorize("iptel.org")) {
    www_challenge("iptel.org", "1");
};
...
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1.4.2. radius_proxy_authorize(realm)

   The function verifies credencials according to RFC2617. If the
   credentials are verified sucessfully then the function will
   succeed and mark the credentials as authorized (marked
   credentials can be later used by some other functions). If the
   function was unable to verify the credentials for some reason
   then it will fail and the script should call proxy_challenge
   which will challenge the user again.

   This function will, in fact, perform sanity checks over the
   received credentials and then pass them along to the radius
   server which will verify the credentials and return whether
   they are valid or not.

   Meaning of the parameter is as follows:

     * realm - Realm is a opaque string that the user agent
       should present to the user so he can decide what username
       and password to use. Usualy this is domain of the host the
       server is running on.
       If an empty string "" is used then the server will
       generate it from the request. From header field domain
       will be used as realm.

   Example 1-4. proxy_authorize usage
...
if (!radius_proxy_authorize("")) {
    proxy_challenge("", "1");  # Realm will be autogenerated
};
...
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Chapter 2. Developer's Guide

   To be done.
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Chapter 3. Frequently Asked Questions

   3.1. What is the meaning of life ?

   3.1. What is the meaning of life ?

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