4.13 Login Menus — ‘raddb/menus’

The menus is a way to allow user the choice between various services he could be provided. The menu functionality is enabled when Radius is compiled with ‘--enable-livingston-menus’ option.

A user is presented a menu after it is authenticated if the RHS of his profile record consists of a single A/V pair in the form:

Menu = <menu-name>

The menu files are stored in directory ‘raddb/menus’.

4.13.1 A menu file syntax.

A menu file is a text file containing a menu declaration and any number of choice descriptions. The menus can be nested to an arbitrary depth.

A comment is introduced by a ‘#’ character. All characters from this one up to the end of line are discarded.

The menu declaration is contained between the words ‘menu’ and ‘end’. Each of these must be the only word on a line and must start in column 1.

Choice descriptions follow the menu declaration. Each description starts with a line containing choice identifier. A choice identifier is an arbitrary word identifying this choice, or a word ‘DEFAULT’. It is followed by comma-separated list of A/V pairs which will be returned to the server when a user selects this choice.

4.13.2 An example of menu files

Single-Level Menu

Suppose the following file is stored under ‘raddb/menus/menu1’:

menu
        *** Welcome EEE user! ***
Please select an option:

        1. Start CSLIP session
        2. Start PPP session
        3. Quit

        Option:
end
# CSLIP choice
# Framed-IP-Address of 255.255.255.254 indicates that the NAS should
# select an address for the user from its own IP pool.
1
        Service-Type = Framed-User,
        Framed-Protocol = SLIP,
        Framed-IP-Address = 255.255.255.254,
        Termination-Menu = "menu1"
# PPP choice
2
        Service-Type = Framed-User,
        Framed-Protocol = PPP,
        Framed-IP-Address = 255.255.255.254,
        Termination-Menu = "menu1"
# A special menu EXIT means abort the session
3
        Menu = "EXIT"
# Return to this menu if no valid choice have been entered 
DEFAULT
        Menu = "menu1"

Now, suppose the ‘raddb/users’ contains the following profile entry:

DEFAULT Auth-Type = System
        Menu = "menu1"

and user ‘jsmith’ has a valid system account and tries to log in from some NAS. Upon authenticating the user, the Radius server sees that his reply pairs contain the Menu attribute. Radius then sends Access-Challenge packet to the NAS with the text of the menu in it. The ‘jsmith’ then sees on his terminal:

        *** Welcome EEE user! ***
Please select an option:

        1. Start CSLIP session
        2. Start PPP session
        3. Quit

        Option:

He then enters ‘2’. The NAS sends the Access-Request packet to the server, which sees that user wishes to use option 2 and replies to the NAS with an Access-Accept packet containing the following attributes:

        Service-Type = Framed-User,
        Framed-Protocol = PPP,
        Framed-IP-Address = 255.255.255.254,
        Termination-Menu = "menu1"

The Termination-Menu in this list makes sure the same process will continue when ‘jsmith’ logs out, i.e. he will be presented the same menu again until he enters choice ‘3’ which will disconnect him.

Nested menus

In this example, the ‘other’ choice refers to the menu above.

menu
        *** Welcome here! ***
Please enter an option:
        ppp     ---     Start PPP session
        telnet  ---     Begin guest login session
        other   ---     Select other option

        Enter your choice:
end
ppp
        Service-Type = Framed-User,
        Framed-Protocol = PPP
telnet
        Service-Type = Login-User,
        Login-IP-Host = 10.11.11.7,
        Login-Service = Telnet,
        Login-TCP-Port = 23
other
        Menu = "menu1"
DEFAULT
        menu = "menu2"

This document was generated by Sergey Poznyakoff on December, 6 2008 using texi2html 1.78.