RE: FTP from iptables

From: Nate Pinchot (npinchot@ccservice.cc)
Date: 09/26/01 

Subject: RE: FTP from iptables
Date: Wed, 26 Sep 2001 12:43:19 -0400
Message-ID: <EAEE14ADB771234B879244F1952F35B703C27B@ccs-mail.ccservice.cc>
From: "Nate Pinchot" <npinchot@ccservice.cc>
To: <focus-linux@securityfocus.com>

>ftp> dir
>500 Illegal PORT Command
>425 Can't build data connection: Connection refused.
>ftp> ls -l
>425 Can't build data connection: Connection refused.
>ftp>
>What happen here?
>I think there are something wrong with ftp module for iptables.
>I already used ip_nat_ftp.
The module is probably not the issue, I have a similar setup running
at both my office and home without the module and can connect to
ftp servers from windows machines and get directory listings/files ok.
The problem here is either in your firewall setup itself or it is
possible that the remote host is also using NAT and masquerading
behind a firewall in which case you should try PASV mode. Also, do you
have any kind of firewall software running on the windows machine?

>FYI, this only happen when I use rh 7.1 with iptables. I've tested
>ipchains with ip_masq_ftp, it goes smooth & well..
My guess is that your problem is the 1st one described because you
had it working with ipchains. You probably just need a little more
tweaking to your iptables rules.

Hope that helps,
______________________________
Nate Pinchot
Corporate Computer Services
npinchot@ccservice.cc <mailto:npinchot@ccservice.cc>

"we're only gonna die because of our own arrogance, that's why we might
as well take our time"
-bradley nowell

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