LWP::Authen::Negotiate - GSSAPI based Authentication Plugin for LWP


   #! /usr/bin/perl -w

   use strict;
   require LWP::UserAgent;

   # uncomment if you want see what is going wrong messages
   #use LWP::Debug qw(+);

   my $ua = LWP::UserAgent->new;
   my $response = $ua->get('http://testwurst.grolmsnet.lan:8090/geheim/');
   if ($response->is_success) {
      print $response->content;  # or whatever
   else {
       die $response->status_line;

just install LWP::Authen::Negotiate, LWP uses it as authentication plugin. Use your LWP::UserAgent Scripts as usual. Authentication is done transparent based on your GSSAPI installation (MIT Kerberos or Heimdal)

WWW-Negotiate Webservers are IIS or Apache with mod_auth_kerb for example.


To see what ist going on add

   use LWP::Debug qw(+);

to yor LWP using Scripts.

(e.g. too see what is going wrong with GSSAPI...)


To see what ist going on (and going wrong) add

   use LWP::Debug qw(+);

to yor LWP using Scripts.

(e.g. too see what is going wrong with GSSAPI...)

the output will look like this:

   LWP::UserAgent::new: ()
   LWP::UserAgent::request: ()
   LWP::UserAgent::send_request: GET http://testwurst.grolmsnet.lan:8090/geheim/
   LWP::UserAgent::_need_proxy: Not proxied
   LWP::Protocol::http::request: ()
   LWP::Protocol::collect: read 478 bytes
   LWP::UserAgent::request: Simple response: Unauthorized
   LWP::Authen::Negotiate::authenticate: authenticate() called
   LWP::Authen::Negotiate::authenticate: target hostname testwurst.grolmsnet.lan
   LWP::Authen::Negotiate::authenticate: GSSAPI servicename     HTTP/moerbsen.grolmsnet.lan@GROLMSNET.LAN
   LWP::Authen::Negotiate::authenticate:  Miscellaneous failure (see text)
   LWP::Authen::Negotiate::authenticate: open(/tmp/krb5cc_1000): file not found

In this case the credentials cache was empty. Run kinit first ;-)



Define to enable ticket forwarding to webserver.


Description of WWW-Negotiate protol

the Kerberos and SPNEGO Authentication module for Apache mod_auth_kerb

Module Homepage

Sofware and APIs related to WWW-Negotiate

describes how to let mod_auth_kerb play together with Internet Explorer and Windows2003 Server


As default Kerberos 5 is selected as GSSAPI mechanism. a later veriosn will make that configureable.


Achim Grolms, <>

Thanks to

Leif Johansson

who has conributed a lot of code from his implementation of the module and send a lot of input, ideas and feedback

Harald Joerg

helped with Kerberos knowledge and does testing on cygwin against IIS and mod_auth_kerb

Christopher Odenbach

does a lot of testing on Linux and Solaris

Dax Kelson

does a lot of testing on Linux

Karsten Kuenne

helped with advice


Copyright (C) 2006 by Achim Grolms <>

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.4 or, at your option, any later version of Perl 5 you may have available.