gdm needing yet another user

[Robert Bihlmeyer <robbe orcus priv at>]

Hi,

>>>>> On 15 Feb 1999 21:05:42 +0100
>>>>> Martin Kasper Petersen <mkp@socsci.auc.dk> said:

 Martin> Because the gdmgreeter is linked to several unaudited
 Martin> libraries. And you really don't want a program with root
 Martin> priviledges snooping around and reading files in user
 Martin> directories. Or accepting arbitrary input from users at the
 Martin> login prompt.

I can see your reasoning. But a separate gdm account doesn't give much 
more security. Once an attacker owns this account, he can snoop
everybody's password, including root's if she ever authenticates to
gdm.

 Martin> Initially gdmgreeter ran as nobody because this user exists
 Martin> on most systems. However, access to the X server is
 Martin> controlled using cookie files and gdmgreeter (and only
 Martin> gdmgreeter) needs to be able to read these to open its
 Martin> window.

Why not let it run as nobody and pass an open filedescriptor
pointing to the cookie file from gdm to gdmgreeter?

Just my 2 e-cent,

	Robbe

-- 
Robert Bihlmeyer	reads: Deutsch, English, MIME, Latin-1, NO SPAM!
<robbe@orcus.priv.at>	<http://stud2.tuwien.ac.at/~e9426626/sig.html>