Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 12 Oct 2009 15:42:01 +0200 (CEST)
From:      Oliver Fromme <olli@lurza.secnetix.de>
To:        freebsd-stable@FreeBSD.ORG
Subject:   Re: openssh concerns
Message-ID:  <200910121342.n9CDg19g066566@lurza.secnetix.de>
In-Reply-To: <20091012094519.GA29445@calvin.ustdmz.roe.ch>

next in thread | previous in thread | raw e-mail | index | archive | help
Daniel Roethlisberger <daniel@roe.ch> wrote:
 > If your situation allows running pf, then there's an alternative
 > method: bind sshd normally to port 22, but use pf to deny direct
 > connections to port 22, redirecting connections to some high port
 > X to port 22 using a `rdr pass' rule.  You can even make
 > exceptions for trusted IP address ranges which are then allowed
 > to SSH in directly on port 22.  That way, an unprivileged process
 > will gain nothing by listening on high port X; it won't get to
 > accept() any SSH connections.

Just for completeness sake, the same can be done easily
with IPFW and "fwd" rules, of course.

Best regards
   Oliver

-- 
Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M.
Handelsregister: Registergericht Muenchen, HRA 74606,  Geschäftsfuehrung:
secnetix Verwaltungsgesellsch. mbH, Handelsregister: Registergericht Mün-
chen, HRB 125758,  Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart

FreeBSD-Dienstleistungen, -Produkte und mehr:  http://www.secnetix.de/bsd

"C++ is to C as Lung Cancer is to Lung."
        -- Thomas Funke



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200910121342.n9CDg19g066566>