Re: RFC: New BPF 'LOOP' instruction

[Paul LeoNerd Evans <leonerd@leonerd.org.uk>]

[-- Attachment #1: Type: text/plain, Size: 1082 bytes --]

On Tue, Aug 03, 2010 at 04:16:02PM +0200, Rémi Denis-Courmont wrote:
> > Is there any way it could be done lazily, at the moment that filter.c
> > knows it has to provide either SKF_TRANS_OFF or SKF_AD_TRANSPROTO?
> 
> You would essentially need to implement dedicated parsing for each
> protocols family.
> So you might as well add an opcode dedicated to IPv6...

And what happens when IPv8 comes along? Or we want to parse IPX/SPX or
any of those thousands of other network protocols?

I'd prefer to keep the BPF layer (relatively) protocol-neutral. Yes, we
have LDX MSH which with hindsight I'd say looks like a very
protocol-specific instruction. But there's nothing protocol-specific
about asking for where the transport header is and what type it is, no
moreso than asking where the network offset and type are, out of the
link-level header. This just extends that layer model.

How to -implement- it is quite another matter.

-- 
Paul "LeoNerd" Evans

leonerd@leonerd.org.uk
ICQ# 4135350       |  Registered Linux# 179460
http://www.leonerd.org.uk/

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 190 bytes --]