FW: Ack/Fin packets dropped.

[Harald Welte]

On Thu, Aug 23, 2001 at 08:28:46AM +0100, Nigel Morse wrote:
> Harald,
> Sorry to send this to you direct, but as the list asked for some Logfiles of
> this stuff, and has then ignored them twice!  Probably due to the fact that
> the traffic on it has grown massively even in just the few months I've been
> on it.

yes, sorry.  And then there is lots of other stuff. I'm travelling, so I
don't have a permantent internet connection as well as not that much time
for staying up-to-date with all netfilter issues.  There are kernel bugs to
be fixed, patches to be tested and forwarded to the kernel, etc, etc.

so a delay of one week or something is nothing special, unfortunately.

> Do you know if anyone is going to look at this issue - I would do myself,
> except that I would be starting from the ground up having never done any
> linux kernel coding.

You don't actually need to do coding.  I'd be happy if you could try to
investigate further.

All you need to know (and understand) is how the TCP protocol works, how
the statemachine looks like, and how the linux netfilter tcp connection
tracking works (sort of).

If you can read C code and have prior knowledge about TCP, it shouldn't 
be too difficult.

The most important file is
/usr/src/linux/net/ipv4/netfilter/ip_conntrack_proto_tcp.c

Once you have figured out how the state transition table is to be read, 
you can think about all possible combinations of packets / events which
might happen in which order at which time.  It's more a mind game than
something related to coding.

It is going to be time-consuming, however.

> Cheers
> Nigel

-- 
Live long and prosper
- Harald Welte / laforge@gnumonks.org                http://www.gnumonks.org
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