Re: [dane] An AD bit discussion

Viktor Dukhovni <viktor1dane@dukhovni.org> Wed, 26 February 2014 17:50 UTC

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Date: Wed, 26 Feb 2014 17:50:12 +0000
From: Viktor Dukhovni <viktor1dane@dukhovni.org>
To: dane@ietf.org
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References: <alpine.LFD.2.10.1402260845520.3528@bofh.nohats.ca> <alpine.LSU.2.00.1402261638490.13302@hermes-1.csi.cam.ac.uk> <530E274D.6030500@redhat.com>
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Subject: Re: [dane] An AD bit discussion
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On Wed, Feb 26, 2014 at 06:41:33PM +0100, Petr Spacek wrote:

> Could you elaborate on reasons for setting AD=1, please?

With "DO=1", applications that only care about the AD bit in the
reply also receive unwanted "RRSIG" records.

Setting "AD=1" may however require a new request option bit, since
RES_USE_DNSSEC sets "DO=1".  I am not sure whether it would be
right to always send "AD=1" when all the nameservers are trusted
and believed to support validation.  Perhaps that's OK, but it may
be prudent to only do this when specifically requested.

-- 
	Viktor.