Re: libpcap patches for DLT_SITA support

["Fulko Hew" <fulko.hew () gmail com>]

On 8/21/07, Guy Harris <guy () alum mit edu> wrote:
> Fulko Hew wrote:
> > Attached is the file that contains the patches to libpcap to support
> > DLT_SITA.
>
> 1) Files added to INSTALL.txt also need to be added to FILES.

Opps, sorry, I forgot about that file (I thought I caught them all).
Do you want me to submit a new patch file with that added?


> 2) the pcap-sita.html file says
>
>         Note: This document was derived from 'pcap.3' and is revision
> controlled as part of the libpcap CVS.
>
> It's derived from the *current* version of pcap.3;


I suppose thats more accurately stated.
If I'm re-submit the patch, I can enhance that too.

I don't think we can
> commit to keeping it up-to-date with respect to the pcap man page, e.g.
> if we add new APIs, without an automatic way of generating
> pcap-sita.html from pcap.3.


No.  I wouldn't expect _you_to keep my file modified with any new APIs,
I would be doing that 'as required'.  My intent with that statement was to
indicate that our coporate copy of the file is not the master copy, but this
copy from the CVS distribution _is_... go and update/patch the CVS copy!

Perhaps there should be a separate document that describes how the ACN
> version of libpcap differs from the standard one.

Thats what that document does.

3) is it intended that the ACN version of libpcap be able to capture
> *only* on ACN devices, not on the regular devices on the machine on
> which it's installed?

Yes

It sounds as if IOP-type devices have names with
> a particular format that isn't likely to match the name of a regular
> Linux networking device, so it should, I think, be possible to support
> both.


You are correct, I intentionally tried to ensure that my naming
convention was different than that of the other OS I was aware of...

Technically I could have made a version that was smart enough to perform
'my' protocol for the ACN remote ports and the generic code for the 'local'
ports, but I didn't do that.  It was my intent to have two different
versions
of wireshark on the machine that was the 'acn' version, and also a std
version.

So the usual time/budget constraints made me separate the two
functionalities as much as possible.  And... I didn't want to 'polute' the
pcap-linux.c  file any more than  I had to, so I would not confuse people
that followed me in non-ACN-land with un-related code.

4) Is the expectation that people not working for SITA (such as SITA's
> customers) will build and install this?


Absolutely.
So since Wireshark was GPL'ed and I'm adding dissectors as part of
the project... and although libpcap is BSD licenced,
I wanted to put 'both' code sets out there to a) do the right thing, and b)
to force our customer to also 'do the right thing', c) get us more out
of the support loop, d) allow others to use the WAN support I've put in
(even though they won't be using the remote device detection portion
of the software).

It is my hope that they would also add more dissectors to Wireshark,
such as for multi-link LAPB and MATIP (rfc2351).
-
This is the tcpdump-workers list.
Visit https://cod.sandelman.ca/ to unsubscribe.