* Jason McIntyre <j...@kerhand.co.uk> [2011-01-30 09:13]:
> On Sat, Jan 29, 2011 at 06:26:29PM +0100, Henning Brauer wrote:
> > * Ted Unangst <ted.unan...@gmail.com> [2011-01-29 17:36]:
> > > On Sat, Jan 29, 2011 at 5:37 AM, Henning Brauer <lists-open...@bsws.de>
> > > wrote:
> > > > no, that's wrong. match rules that matched during evaluation get their
> > > > counters updated. aka, your rule did not match.
> > > 
> > > ok, that's wrong. :)
> > > 
> > > Somebody else told me to add a "pass all" rule at the top of the rule
> > > set.  Then it did work.  But pass all is the default.  Somehow adding
> > > it explicitly changes the behavior of match rules.  I know the rule
> > > matches because it does so after adding pass all.
> > 
> > ok, we get into semantic nitpicking...
> > there is no default "pass all" rule.
> > packets are being passed by default.
> > that is an important difference - no state is ever created for those
> > packets being passed since they didn't match a pass rule.
> > now i wonder wether we fail to update the counters on match rules for
> > the !state case... and the more i think about it the more i think that
> > is the case.
> > yup, indeed.
> > not trivial to fix. the state is the link to the match rules.
> > 
> > a change on one of my laptops (now if i knew which...) is likely to
> > fix that as a side effect, but it has some bad bugs. no way it makes
> > 4.9. and a fix for this issue would be either intrusive or very ugly
> > (and still not trivial), thus not a viable option either. live with it
> > for now.
> > 
> > did i mention that stateless is pretty dumb anyway? :)
> > 
> 
> is this correct:
> 
> - match rules will not work if "no state" is also used on the rule (not
>   sure that would make sense anyway)

well, they do "work".

> - all packets are passed by default, but effectively with "no state"

correct.

> - "no state" is incompatible with counters

no, that's wrong. there is a bug with counters on match rules in the
no state case, that's gonna be fixed somewhen.

> - any packets passed without matching any rules (i.e. are not
>   specifically blocked) are not accounted for (statistically)

well, they still update the global counters. 

> that seems like a whole heap of gotchas that we don;t talk about. i
> think we should try and document this stuff.

hmm. it really comes down to the no state for packets not matching any
pass rules.

-- 
Henning Brauer, h...@bsws.de, henn...@openbsd.org
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