Re: [dane] An AD bit discussion

Mark Andrews <marka@isc.org> Tue, 11 March 2014 08:09 UTC

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To: Petr Spacek <pspacek@redhat.com>
From: Mark Andrews <marka@isc.org>
References: <alpine.LFD.2.10.1402260845520.3528@bofh.nohats.ca> <20140226155752.GT21390@mournblade.imrryr.org> <alpine.LFD.2.10.1402261114460.3528@bofh.nohats.ca> <87a9d0ei30.fsf@mid.deneb.enyo.de> <20140311064639.C613F10E0717@rock.dv.isc.org> <531EBC13.1060007@redhat.com>
In-reply-to: Your message of "Tue, 11 Mar 2014 08:32:35 +0100." <531EBC13.1060007@redhat.com>
Date: Tue, 11 Mar 2014 19:09:01 +1100
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Archived-At: http://mailarchive.ietf.org/arch/msg/dane/y1UcwtQ6WriNnYrPPFXKpbPI7Pc
Cc: dane@ietf.org
Subject: Re: [dane] An AD bit discussion
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In message <531EBC13.1060007@redhat.com>;, Petr Spacek writes:
> On 11.3.2014 07:46, Mark Andrews wrote:
> >
> > In message <87a9d0ei30.fsf@mid.deneb.enyo.de>;, Florian Weimer writes:
> >> * Paul Wouters:
> >>
> >>> Sorry, I mistook the flags in the struct to be the DNS flags. Let me
> >>> rephrase it as "a DNS API call that returns the presence or lack of
> >>> AD bit"
> >>
> >> I think this focus on the AD bit is a grave mistake.  There are other
> >> technologies for securing DNS data.  At least one of them (installing
> >> an authenticated copy of the zone in the resolver) is superior to
> >> DNSSEC according to various criteria, but full implementation requires
> >> that the resolver clears the AD bit.
> >
> > You can set AD=1 with a local copy of the zone.  I actually run
> > named locally like this with full dnssec validation of results
> > returned from the local zone.  You can also just assert AD=1 without
> > doing validation if that is what your local policy states on secure
> > transfer.
> 
> Maybe it is not a problem but I have to ask:
> 
> What if DS records in parent zone are somehow broken? Validating resolvers 
> will see the child zone as bogus but authoritative server for such zone will 
> happily set AD=1.

Yes.
 
> I'm curious if this conflicts with AD bit definition in RFCs or not.
 
It is permitted.

> -- 
> Petr^2 Spacek
> 
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-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka@isc.org