Re: NFNL_NFA_NEST

[Patrick McHardy <kaber@trash.net>]

Pablo Neira Ayuso wrote:
> Patrick McHardy wrote:
> 
>>One of the worst mistakes in nfnetlink in my opinion was the
>>introduction of the NFNL_NFA_NEST bit. It prevents us from
>>using a large part of the generic netlink stuff, since that
>>just interprets it as a really huge attribute type. Since
>>its not used even for anything, this is really annoying.
> 
> 
> I'm using this bit to convert attribute headers from host byte order to
> network byte order in conntrackd. I'm unsure about how I would do the
> conversion if we remove such bit.


That was the original idea behind it. But where do we use host byte
order?

>>Unfortunately there is no easy way to get rid of it, current
>>userspace code sends it to the kernel, so even if we stop
>>including it in the kernel, we need to deal with it for
>>compatibilty.
> 
> 
> We have a field in the nfnetlink that contains the protocol version that
> we can use for this kind of changes without breaking backward.


If we still support the old stuff we can't get rid of it.
I would really like to remove all the duplicated code and
use the much nicer netlink infrastructure we have today.