NIS and NFS

["Jorge R . Csapo" <jorge@completo.com.br>]

Hi all, I've been wrecking my brains over this one but I'm threading water:

I have a Linux-only network with one server and a number of stations. The
server's /home directory is exported and mounted by the stations via NFS. The
server also serves NIS and the setup lets users log onto any one of the
stations and have the same /home/~user everywhere.

My problem is that every user is 'root' at his/her own station. Of course NFS
has been configured not to grant access to remote root users, but there's
nothing to prevent users from 'becoming' someone else with su and then the
NFS/NIS authentication scheme falls flat on its face.

For instance:

. User 'jdoe' logs onto his own station. He's authenticated via NIS and mounts
  /home from the server.
. jdoe then runs 'su' and becomes root.
. root runs 'su - jblow' and becomes jblow.
. jblow cds to /home/jblow...

After going through man docs, howtos and google entries for NIS, NFS and su and
drawing a blank, I'd appreciate any and all insights you people may have on
the subject.

TIA,

-- 
Jorge R. Csapo
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With a PC, I always felt limited
by the software available.
On Unix, I am limited only by my knowledge.
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