How to mark RTSP child connections with different value.

How to mark RTSP child connections with different value.

[Thierry Du Tre]

Hi,

I am trying to apply some QoS for RTSP traffic forwarded by an OpenWRT
gateway (Attitude Adjustment + patches).

The RTSP helper is loaded and succesfully expects the incoming
streams, which arrive at the client in the NAT'ed lan.
Multiwan is also active, this is using part of the marking bits (i.e.
0xF0000000 ) to select the appropriate routing table.

In this product, interface drivers sort outgoing frames in different
queues based on part of the marking bits (i.e. 0x0F000000).
Netfilter rules are present in the forwarding chain to mark streams
destined at tcp port 554 with specific qos value (i.e 0x08000000).
This mark is saved as connmark at the end of the forwarding chain, and
restored at the start. If after restore, the mark is still 0, only
then all qos rules are being evaluated.

When RTSP helper succesfully predicts incoming streams, these childs
automatically inherit the connection mark, and as such will be marked
with the same mwan and qos bits as the parent connection. For mwan
this is ok, but for qos a different (higher) value would be prefered
(i.e. 0x0A000000).
Ideally, the child streams should be assigned a specified connmark
value when RTSP helper is predicting them.
A generic solution that would be applicable to parent-child
connections handled by other helpers would be nice :-)

So ... what are my options ?

--
Thierry

Re: How to mark RTSP child connections with different value.

[Pascal Hambourg]

Hello,

Thierry Du Tre a écrit :
> 
> I am trying to apply some QoS for RTSP traffic forwarded by an OpenWRT
> gateway (Attitude Adjustment + patches).
> 
> The RTSP helper is loaded and succesfully expects the incoming
> streams, which arrive at the client in the NAT'ed lan.
> Multiwan is also active, this is using part of the marking bits (i.e.
> 0xF0000000 ) to select the appropriate routing table.
[...]
> When RTSP helper succesfully predicts incoming streams, these childs
> automatically inherit the connection mark, and as such will be marked
> with the same mwan and qos bits as the parent connection. For mwan
> this is ok, but for qos a different (higher) value would be prefered
> (i.e. 0x0A000000).
> Ideally, the child streams should be assigned a specified connmark
> value when RTSP helper is predicting them.
> A generic solution that would be applicable to parent-child
> connections handled by other helpers would be nice :-)

What about matching the packets of the RTSP streams and MARK/CONNMARK
them when they arrive ?

-m state --state RELATED : match the first packet of related streams
-m conntrack --ctstatus EXPECTED : match all packets of expected streams
-m helper --helper "rtsp" : match all packets related to the RTSP helper