Am Dienstag, 8. Mai 2007 schrieb Franck Joncourt: > On Tue, May 08, 2007 at 01:14:18PM +0200, Lutz Feldgen wrote: > > On Tue, May 08, 2007 at 07:47:48AM +0200, Lutz Feldgen wrote: > > >>I try to get the following working with iptables: > > >> > > >>incoming ftp (passive or active) > > >>outgoing ftp (to single special ftp-server) > > >>apt-get > > >> > > >>Can anybody help me with this, its driving me mad... > > > > > >First of all, what do you really want ? Running a ftp server on your own > > >computer or being able to access external ftp server, or perhaps both. > > > > > >Have a look at those two pictures in order to see the differences > > > between active and passive mode (french link but it does not matter) : > > > > > >http://smhteam.info/wiki/index.linux.php5?wiki=DiagrammesFtp > > > > > >What rules have you tried to run by now ? > > > > thanks for the quick answer and sorry for the incomplete description. > > Right now I cannot fetch the used ruleset from the server but my > > intention is to keep it as secure for my server as possible. > > I want to run an ftp-server to give the possibility to upload something > > but also need access to an external ftp-server for backups. At least > > apt-get should find a way to fetch packets through the firewall. The > > decision whether to run active or passive on my own ftp-server depends > > on the security level of the underlying ruleset. > > About your ftp-server, I would choose passive mode as you do not > initiate data connexion, the client do it on an unprivileged port. > > Anyway here is some piece of code (just an example): > > I assume your default policy is DROP for INPUT and OUTPUT chains. > > iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT > iptables -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT > > # Deal with your own ftp server > You have to allow NEW incoming connexions from the client on port 21: > iptables -A INPUT -p tcp --syn --dport 21 -m state --state NEW -j ACCEPT > > # Deal with external ftp servers > About apt you have to allow outgoing connexions to the external servers > on port 21 > iptables -A OUTPUT -p tcp --syn --dport 21 -m state --state NEW -j ACCEPT > > And do not forget to make sure ip_conntrack_ftp module is loaded. > > It should work ! I did not give it a try. > > Once it works, you can start thinking about security.
maybe you should add --dest <serveraddress> to the output rules to access only the wanted ftp server(s) for apt-get you can use ftp or http so it should work as easy as the rest -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]