From: Patrick McHardy <kaber@trash.net>
To: Ron Lai <ronlai@cs.stanford.edu>
Cc: netfilter@vger.kernel.org,
Netfilter Development Mailinglist
<netfilter-devel@vger.kernel.org>
Subject: Re: Problems with nf_nat_ftp.ko and nf_conntrack_ftp.ko in 2.6.22.6
Date: Mon, 29 Oct 2007 13:51:47 +0100 [thread overview]
Message-ID: <4725D763.9080104@trash.net> (raw)
In-Reply-To: <002401c81638$d97f2ff0$050ba8c0@FireEye.com>
Ron Lai wrote:
> The packet dump from the 2.6.22.6 box in the middle is attached. In the
> trace 172.16.119.91 is the original IP address of the FTP client and
> 172.16.255.123 is the NATted address. The FTP server's address is
> 172.16.118.1.
>
> The problem happens between packet 31 and packet 34. Packet 31 indicates
> that the client expects ACK number 0x64b4dda9 for the PORT command it
> sends. However, the ACK number it actually gets is 0x64b4dda8.
Thats really odd. It properly adjusts the sequence number in the
original direction by +1, but incorrectly adjusts the acknowledgement
in the reply direction by -2. I don't see how this could happen with
the vanilla 2.6.22 kernel, are you using any additional patches?
Otherwise please edit net/ipv4/netfilter/nf_nat_helper.c and add
a #define DEBUG at the first line, recompile and post the output
of the failed session (ideally two failed sessions). Thanks.
prev parent reply other threads:[~2007-10-29 12:54 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <001f01c8142e$e6a67960$ea50f53c@FireEye.com>
2007-10-23 13:17 ` Problems with nf_nat_ftp.ko and nf_conntrack_ftp.ko in 2.6.22.6 Patrick McHardy
2007-10-24 12:24 ` Ron Lai
2007-10-29 12:51 ` Patrick McHardy [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4725D763.9080104@trash.net \
--to=kaber@trash.net \
--cc=netfilter-devel@vger.kernel.org \
--cc=netfilter@vger.kernel.org \
--cc=ronlai@cs.stanford.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).