Re: [Resolverless-dns] Paper on Resolver-less DNS

Joe Abley <jabley@hopcount.ca> Thu, 15 August 2019 22:11 UTC

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From: Joe Abley <jabley@hopcount.ca>
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Date: Thu, 15 Aug 2019 18:11:02 -0400
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Cc: Eric Orth <ericorth=40google.com@dmarc.ietf.org>, Ben Schwartz <bemasc@google.com>, resolverless-dns@ietf.org, John Levine <johnl@taugh.com>
To: Fred Baker <fredbaker.ietf@gmail.com>
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Subject: Re: [Resolverless-dns] Paper on Resolver-less DNS
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On 15 Aug 2019, at 18:01, Fred Baker <fredbaker.ietf@gmail.com> wrote:

> One thing I would want to be certain of is that the host did DNSSEC validation. It’s the only way I know of to verify the validity of the RR.

In the case of a client doing resolverless DNS with a server, presumably it has already

 - looked up the name using a resolver
 - established a TCP connection
 - completed a TLS handshake with some degree of certificate validation
 - potentially supplied acceptable credentials for HTTP authentication, if the server needs them

before it is in a position to do name resolution within the resulting HTTPS bundle. What is the reasoning to require that additional precautions be taken at this point, compared to the conventional behaviour where the client continues to get fake results from the cache of the poisoned resolver?

I agree the DNSSEC validation at the client would be nice to see, but I think that's a more general statement than one that is specific to this case.


Joe