From owner-freebsd-questions Fri May 7 1:52: 9 1999 Delivered-To: freebsd-questions@freebsd.org Received: from mel.alcatel.fr (mel.alcatel.fr [212.208.74.132]) by hub.freebsd.org (Postfix) with ESMTP id 9216C14E88 for ; Fri, 7 May 1999 01:52:01 -0700 (PDT) (envelope-from Thierry.Herbelot@alcatel.fr) Received: from aifhs2.alcatel.fr (mailhub.alcatel.fr [155.132.180.80]) by mel.alcatel.fr (ALCANET/SMTP) with ESMTP id JAA20116 for ; Fri, 7 May 1999 09:48:23 +0200 Received: from lune.telspace.alcatel.fr (lune.telspace.alcatel.fr [155.132.144.65]) by aifhs2.alcatel.fr (ALCANET/SMTP2) with ESMTP id KAA01229 for ; Fri, 7 May 1999 10:47:03 +0200 (MET DST) Received: from telss1 (telss1.telspace.alcatel.fr [155.132.51.4]) by lune.telspace.alcatel.fr (8.9.1a/8.9.1) with ESMTP id KAA10867 for ; Fri, 7 May 1999 10:36:58 +0200 (MEST) Received: from telspace.alcatel.fr by telss1 (8.8.8+Sun/SMI-SVR4) id KAA08773; Fri, 7 May 1999 10:39:19 +0200 (MET DST) Message-ID: <3732A811.7F51584B@telspace.alcatel.fr> Date: Fri, 07 May 1999 10:45:05 +0200 From: Thierry Herbelot Reply-To: thierry.herbelot@alcatel.fr Organization: Alcatel CIT Nanterre X-Mailer: Mozilla 4.5 [en] (X11; I; SunOS 5.5.1 sun4m) X-Accept-Language: en MIME-Version: 1.0 To: questions Subject: Passive FTP with natd ? Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Hello, I've set up a small home network with two 3.1-Stable machines, one being the gateway to the Internet via a TV cable connection (ethernet connection to the cable modeme and DHCP negociation for the external IP address - the two machines were CVSupped and "make world"-ed during this week). This seteup works quite well (and with very little load on the gateway - I'm even contemplating changing the gateway : I've got an oldish 386sx which is presently idle). But one thing is still annoying : I must use a passive connection with FTP when I connect from the internal machine to an outside server (case in point : I was trying to download RedHat 6.0 from cdrom.com). When I read the lialias(3) man page, it seems that the aliasing code can cope with ftp transfers and modifies on-the-fly FTP packets so that you don't have to use the "passive" option (this is essentially intyeresting for graphical ftp clients where it is not obvious to know how to switch to passive mode). Thus : is it possible to setup natd so as to modify FTP packets ? (is there a specific rule to insert into rc.firewall ?) TIA TfH PS : extract from libalias(3) int PacketAliasOut(char *buffer, int maxpacketsize) An outgoing packet coming from the local network to a remote machine is aliased by this function. The IP packet is pointed to by buffer r, and maxpacketsize indicates the maximum packet size permissible should the packet length be changed. IP encoding protocols place address and port information in the encapsulated data stream which have to be modified and can account for changes in packet length. Well known examples of such protocols are FTP and IRC DCC. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message