From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Satrapa Subject: Re: Apply rules to 1 UDP port but port used as a socket: possible? Date: Wed, 11 Feb 2004 14:00:16 +1100 Sender: netfilter-admin@lists.netfilter.org Message-ID: <40299AC0.80104@lintelsys.com.au> References: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: Errors-To: netfilter-admin@lists.netfilter.org List-Help: List-Post: List-Subscribe: , List-Id: List-Unsubscribe: , List-Archive: Content-Type: text/plain; charset="windows-1252"; format="flowed" To: zze-Proxy GRALL O ext FTRD/SVA/LAN Cc: netfilter@lists.netfilter.org zze-Proxy GRALL O ext FTRD/SVA/LAN wrote: > I'm trying to use a socket (on port 1727) to decode some proprietary UDP = > packets. When I've decoded them I want to apply a DNAT rule (and then a=20 > SNAT too) to this port using a filter on @IP:port source for all=20 > following packets=85 So do you have Machine F which is the firewall, and machines A, B and C whi= ch are the ultimate destinations, and you want to have UDP packets from mac= hine X (elsewhere) being sent to A, B or C by F based on some information = in the first packet F receives from a new host X? You could write your "mon= itor" to set up new rules based on the first packets that arrive, with the = remainder being "deflected" by the firewall rules.