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Date: Thu, 22 Sep 2005 18:09:59 +0200
From: Jeremie Le Hen <jeremie@le-hen.org>
To: markzero <mark@darklogik.org>
Message-ID: <20050922160959.GQ24643@obiwan.tataz.chchile.org>
References: <20050922152718.GB91509@logik.internal.network>
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Cc: freebsd-security@freebsd.org
Subject: Re: Tunnel-only SSH keys
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Hi,

> I once read somewhere that it's possible to limit SSH pubkeys to
> 'tunnel-only'. I can't seem to find any information about this
> in any of the usual places.
> 
> I'm going to be deploying a few servers in a couple of days and
> I'd like them to log to a central server over an SSH tunnel (using
> syslog-ng) however I'd like to prevent actual logins (hence
> 'tunnel-only').
> 
> Can this be done with OpenSSH? I'd like to try and stay away from
> the complexities of a chrooted-stunnel for now...

I think you can use /bin/false as shell, and then use ``ssh -nN''
from the client.  I've not tested this, but I guess this should
work.

Regards,
-- 
Jeremie Le Hen
< jeremie at le-hen dot org >< ttz at chchile dot org >