On 2023-03-26, at 22:39:42 +0200, Pablo Neira Ayuso wrote:
> On Fri, Mar 24, 2023 at 11:59:04PM +0100, Florian Westphal wrote:
> > Jeremy Sowden <jeremy@azazel.net> wrote:
> > > +ip daddr 10.0.0.1 tcp dport 55900-55910 dnat ip to 192.168.127.1:5900-5910/55900;ok
> > > +ip6 daddr 10::1 tcp dport 55900-55910 dnat ip6 to [::c0:a8:7f:1]:5900-5910/55900;ok
> > 
> > This syntax is horrible (yes, I know, xtables fault).
> > 
> > Do you think this series could be changed to grab the offset register from the
> > left edge of the range rather than requiring the user to specify it a
> > second time?  Something like:
> > 
> > ip daddr 10.0.0.1 tcp dport 55900-55910 dnat ip to 192.168.127.1:5900-5910
> > 
> > I'm open to other suggestions of course.
> 
> Not only syntax, main problema is that this port shift support has to
> work with NAT maps, otherwise this needs N rules for different
> mappings which takes us back to linear rule inspection.
> 
> Jeremy, may I suggest you pick up on the bitwise _SREG2 support?  I
> will post a v4 with small updates for ("mark statement support for
> non-constant expression") tomorrow. Probably you don't need the new
> AND and OR operations for this? Only the a new _SREG2 to specify that
> input comes from non-constant?

Cool, I will focus on this for the moment.

J.