Variable-length data?

Variable-length data?

[Bruce Guenter]

Greetings.

I have written a simple filter for matching multiple network masks in a
list.  From what I can see, the actual netfilter data has to be constant
sized.  Is this true, or is there an easy way to have a non-fixed size
list of addresses (for example)?  It seems rather wasteful to allocate a
large array when only a small one is needed.

Thanks.
-- 
Bruce Guenter <bruceg@em.ca> http://em.ca/~bruceg/ http://untroubled.org/
OpenPGP key: 699980E8 / D0B7 C8DD 365D A395 29DA  2E2A E96F B2DC 6999 80E8

Re: Variable-length data?

[Henrik Nordstrom]

On Wed, 15 Sep 2004, Bruce Guenter wrote:

> I have written a simple filter for matching multiple network masks in a
> list.  From what I can see, the actual netfilter data has to be constant
> sized.  Is this true, or is there an easy way to have a non-fixed size
> list of addresses (for example)?

iptables matches (and targets) must use a static size matchdata structure 
per match (or target).

> It seems rather wasteful to allocate a large array when only a small one 
> is needed.

It is.

Regards
Henrik