Re: [Doh] WG Review: DNS Over HTTPS (doh)

Adam Roach <adam@nostrum.com> Wed, 20 September 2017 22:54 UTC

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To: Toerless Eckert <tte@cs.fau.de>, ietf@ietf.org
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References: <150549029332.2975.12341647131707994474.idtracker@ietfa.amsl.com> <20170920151458.GA22670@faui40p.informatik.uni-erlangen.de>
From: Adam Roach <adam@nostrum.com>
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Date: Wed, 20 Sep 2017 17:54:09 -0500
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Subject: Re: [Doh] WG Review: DNS Over HTTPS (doh)
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The dichotomy you lay out doesn't make sense because HTTP already has a 
well-defined security model. As it stands, HTTPS  implies the use of 
trusted public roots, and CAB Forum Baseline Requirements section 9.2.1 
forbids the issuance of a cert for IP addresses. One of the things that 
is appealing about HTTPS as a substrate (for better or worse) is that it 
has a well-defined and proven scalable system for the kind of security 
issues you describe below.

The issue with putting discovery in this charter is that it's the wrong 
community of interest and expertise for what you propose. I would 
imagine that this is the same reason that RFC3315bis is being done in 
DHC rather than V6OPS (although -- full disclosure -- that decision is a 
bit outside of what I tend to track).

/a

On 9/20/17 10:14 AM, Toerless Eckert wrote:
> On Fri, Sep 15, 2017 at 08:44:53AM -0700, The IESG wrote:
> [...]
>> Specification of how the DNS data may be used for new use cases, and
>> the discovery of the DOH servers, are out of scope for the working group.
> I disagree on this becoming a working group unless the charter says either:
>
> a) Discovery is in scope
>
> I have no specific preferences of what discovery is done, i just
> think that the security discussion needs to take the discovery being used
> into account. I can already see how DoH clients will just use some
> configured IP address for the DoH server and accept whatever self-signed
> TLS certs are being offered. And the industry thinks its great security
> improvement because it uses TLS. I am sure there are enough people willing
> to work on DoH that would be able to write down how to do that discovery piece
> more securely, so why stop them doing it by writing "out of charter".
>
> or
>
> b) Security is optional. The documents will sprinkle some security fairy
> dust in by mandating simple buzzwords like TLS Vmax so we can escape further
> security discussions.
>
> ;-)
>
> Cheers
>      Toerless
>