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Date: Thu, 31 Aug 2006 18:13:55 +0200
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: 1.5.21: Win 2003 R2 domain user ssh shows whoami sshd_server (password  auth)
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On Aug 30 14:05, Serban Simu wrote:
> So my questions would be:
> 
> (1) I did find a work around, but what is the explanation of this 
> problem and what is a good, solid work around?

After some debugging I found that the explanation is that sshd drops
all supplementary groups from the otherwise privileged user token. 
This results in a minimized user token when calling initgroups, which
in turn calls NetUserGetGroups, which in turn returns "Access denied".
The solution is to drop back to the original process token before
calling NetUserGetGroups from initgroups.  I've checked in a patch
which should be available in the next developers snapshot from
http://cygwin.com/snapshots/

A solid workaround if you're trying to get the same with the current
Cygwin:  Add all users which want to log in this way to the gr_mem
field of the approrpiate groups in /etc/group.  In your example case,
it would look like this:

Test Users:S-1-5-21-4293257363-1756470469-1603820055-1123:11123:test1


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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