OC4J, JavaSSO and standard Linux authentication

Question

Having "fixed" my earlier "problem" (<Problems using JavaSSO in simple scenario I've now been able to get JavaSSO working as expected using the default file-based security provider.
What I would really like to do, however, is have the authentication performed against the users and groups known to the Linux O/S on which OC4J is running - i.e. by having the user provide their standard Linux username/password.
I had initially thought that I could achieve this through use of com.sun.security.auth.module.UnixLoginModule - but soon(ish) realised that this was actually carrying out authentication of the user running the application server, rather than the user trying to log in.
It looks like ShadowJAAS (<http://freshmeat.net/projects/shadowjaas/>) might be what I'm after... Does anybody have any experience of using this with OC4J? Or can anybody recommend any alternatives?
Cheers,
Alistair.

Answer 1

Having not had much luck with ShadowJAAS, I thought I'd try a PAM based authentication module called JAAS-PAM:
<http://jaas-pam.sourceforge.net/index.html>
This took considerably more effort to get up and running than ShadowJAAS, but I seem to be suffering from essentially the same problem. Adding some debug output into the JAAS-PAM source provided me with the following, when I attempt to log in via JavaSSO:
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 INITIALIZE method has been invoked
07/05/23 13:52:32 subject is Subject:
07/05/23 13:52:32 options is {service=login}
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 LOGIN method has been invoked
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 HANDLE method has been invoked
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 HANDLE method has been invoked
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 Got a passwordcallback
07/05/23 13:52:32 Password is supplied as [C@c7539
07/05/23 13:52:32 Prompt is supplied as Password:
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 status is 0 which is Success
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 COMMIT method has been invoked
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 FREEPAM method has been invoked
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 INITIALIZE method has been invoked
07/05/23 13:52:32 subject is Subject:
07/05/23 13:52:32 options is {service=login}
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 LOGIN method has been invoked
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 HANDLE method has been invoked
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 HANDLE method has been invoked
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 Got a passwordcallback
07/05/23 13:52:32 Password is supplied as null
07/05/23 13:52:32 Prompt is supplied as Password:
07/05/23 13:52:32 ******************************************************************
07/05/23 13:52:32 java.lang.NullPointerException
07/05/23 13:52:32       at java.lang.String.<init>(String.java:173)
07/05/23 13:52:32       at java.lang.String.valueOf(String.java:2591)
07/05/23 13:52:32       at ch.odi.jaaspam.PamLoginModule$JaasPamCallback.answer(PamLoginModule.java:300)
   :As with ShadowJAAS before it, it looks as though authentication is taking place twice: once with the password I've supplied, and then again with a null password.
It's worth noting that the sample (Java SE) applications provided with both authentication modules work as expected - it's only when I try to use them with JavaSSO that I see these problems.
This leads me to believe that the problem lies with JavaSSO (or, at least, the way I'm configuring it), rather than in the authentication modules themselves.
I'm running out of ideas here, so if anybody has a nugget of useful information, please share!
Many thanks,
Alistair.