Re: [dane] AD bit handling in stub-resolvers: conclusions and compromises

Paul Wouters <paul@nohats.ca> Wed, 09 April 2014 01:42 UTC

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Date: Tue, 8 Apr 2014 21:42:33 -0400 (EDT)
From: Paul Wouters <paul@nohats.ca>
To: Nico Williams <nico@cryptonector.com>
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Subject: Re: [dane] AD bit handling in stub-resolvers: conclusions and compromises
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On Tue, 8 Apr 2014, Nico Williams wrote:

> We should want fail-closed semantics.  I very much prefer having a
> caching validating local server.  I don't mind making people (and
> configuration apps) explicitly set a global in /etc/resolv.conf to
> disable AD stripping.

>> After further discussion, it seems that pwouters is okay with AD bit
>> stripping in stub resolver if it is explicitly requested by a calling
>> application. (E.g. by special resolver initialization.)
>
> Again, we need fail-closed semantics.

You do if you are _asking_ for it. But you need to ask or else you break
backwards compatibility with a rack of servers using a nearby trusted
resolver.

Paul