The variables defined by the server are:

     %{Attribute-Name}               Corresponding value for Attribute-Name
                                     in request
     %{request:Attribute-Name}       Corresponding value for Attribute-Name
                                     in request
     %{reply:Attribute-Name}         Corresponding value for Attribute-Name
                                     in reply
     %{proxy-reply:Attribute-Name}   Corresponding value for Attribute-Name
                                     in the proxy reply (if it exists)

     %{config:section.subsection.item} Corresponding value in 'radiusd.conf'
                                       for the string value of that item.

  The %{config:...} variables should be used VERY carefully, as they
may leak secret information from your RADIUS server, if you use them
in reply attributes to the NAS!

  e.g.

  %{User-Name}			 The string value of the User-Name attribute.
  %{proxy-reply:Framed-Protocol} The string value of the Framed-Protocol
				 attribute, from the proxy reply.
  %{config:modules.unix.passwd}  The string value of the 'passwd' configuration
				 item in the 'unix' module, in the 'modules'
				 section of radiusd.conf.

Additionally, you can use conditional syntax similar to ${foo:-bar} as
defined in 'sh'.  For example:

  1.  %{Foo:-bar}
    When attribute Foo is set:  returns value of Foo
    When attribute Foo unset:   returns literal string 'bar'

  2.  %{Foo:-%{Bar}}
    When attribute Foo is set:  returns value of attribute Foo
    When attribute Foo unset:   returns value of attribute Bar (if any)

  3.  %{Foo:-%{bar:-baz}}
    When attribute Foo is set:  returns value of attribute Foo
    When attribute Foo unset:   returns value of attribute Bar (if any)
    When attribute Bar unset:   returns literal string 'baz'


When calling an external program (e.g. from Exec-Program-Wait), these
variables can be passed on the command line to the program.  In
addition, the server places all of the attributes in the RADIUS
request into environment variables for the external program.  The
variables are renamed under the following rules:

  1.  All letters are made upper-case.

  2.  All hyphens '-' are turned into underscores '_'

so the attribute User-Name can be passed on the command line to the
program as %{User-Name}, or used inside the program as the environment
variable USER_NAME (or $USER_NAME for shell scripts).

If you want to see the list of all of the variables, try adding a line
'printenv > /tmp/exec-program-wait' to the script.  Then look in the
file for a complete list of variables.

The following one-character variables are also defined.  However, they
are duplicates of the previous general cases, and are only provided
for backwards compatibility.  They WILL BE removed in a future
release.  They also do NOT permit the use of conditional syntax
(':-'), as described above.


    Variable  Description		  Proper Equivalent
    --------  -----------		  ----------------
     %a       Protocol (SLIP/PPP)	  %{Framed-Protocol}
     %c       Callback-Number		  %{Callback-Number}
     %d       request day (DD)
     %f       Framed IP address		  %{Framed-IP-Address}
     %i       Calling Station ID	  %{Calling-Station-Id}
     %l       request timestamp
     %m       request month (MM)
     %n       NAS IP address		  %{NAS-IP-Address}
     %p       Port number		  %{NAS-Port-Id}
     %s       Speed (PW_CONNECT_INFO)	  %{Connect-Info}
     %t       request in ctime format
     %u       User name			  %{User-Name}
     %A       radacct_dir		  %{config:radacctdir}
     %C       clientname
     %D       request date (YYYYMMDD)
     %H	      request hour
     %L       radlog_dir		  %{config:logdir}
     %M       MTU			  %{Framed-MTU}
     %R       radius_dir		  %{config:raddbdir}
     %S       request timestamp
                in SQL format
     %T       request timestamp
                in database format
     %U       Stripped User name	  %{Stripped-User-Name}
     %V       Request-Authenticator
                (Verified/None)
     %Y       request year (YYYY)
     %Z       All request attributes
               except password
               (must have a big buffer)