Stéphane Veyret <sveyret@xxxxxxxxx> wrote: > Le dim. 19 mai 2019 à 22:14, Florian Westphal <fw@xxxxxxxxx> 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.
