netfilter-devel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Florian Westphal <fw@strlen.de>
To: "Stéphane Veyret" <sveyret@gmail.com>
Cc: Florian Westphal <fw@strlen.de>, netfilter-devel@vger.kernel.org
Subject: Re: Expectations
Date: Wed, 22 May 2019 08:42:13 +0200	[thread overview]
Message-ID: <20190522064213.sh54v25tazvofewz@breakpoint.cc> (raw)
In-Reply-To: <CAFs+hh6D5nj7UNBfXt+KPO4vOsWOZHkRY1Lpd1UxwiQJ=5Y-dA@mail.gmail.com>

Stéphane Veyret <sveyret@gmail.com> wrote:
> Le dim. 19 mai 2019 à 22:14, Florian Westphal <fw@strlen.de> a écrit :
> > RTSP looks rather complex, wouldn't it be better/simpler to use
> > a proxy?
> 
> RTSP does not seem that complex to me.

Oh?  It looked complex to me:
https://www.rfc-editor.org/rfc/rfc7826.txt

but perhaps you only need a subset of this..?

> It is a bit like FTP: the
> client sends a first connection in order to define the ports to use,
> then the server initiates the connection on those ports.
> I saw some examples of RTSP helper libraries written for old versions
> of the kernel (focused on iptables), so I think it would not be very
> complicated to port to newest versions.

> > We have TPROXY so we can intercept udp and tcp connections; we have
> > ctnetlink so the proxy could even inject expectations to keep the real
> > data in the kernel forwarding plane.
> 
> It would mean we would need to open/expect a very wide range of ports,
> if we don't look into the first message to grab the real used port…

No, the idea is to parse the RTSP data in the proxy, then inject the
expectations based on the exchanged/requested information.

No functional change wrt. a kernel based helper, except that the RTSP
data is parsed in userspace.

> By the way, as I had no feedback for the moment regarding expectation
> patch I sent (yes, I know it needs time to code review), I just

see
https://patchwork.ozlabs.org/patch/1101154/

nf-next is closed at this time, I expect that it will open in the next
few days and that your patch will be accepted or given feedback by then.

  reply	other threads:[~2019-05-22  6:42 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-18 13:53 Expectations Stéphane Veyret
2019-05-19 20:14 ` Expectations Florian Westphal
2019-05-22  6:36   ` Expectations Stéphane Veyret
2019-05-22  6:42     ` Florian Westphal [this message]
2019-05-22  8:34       ` Expectations Stéphane Veyret

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=20190522064213.sh54v25tazvofewz@breakpoint.cc \
    --to=fw@strlen.de \
    --cc=netfilter-devel@vger.kernel.org \
    --cc=sveyret@gmail.com \
    /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).