W3C home > Mailing lists > Public > ietf-http-wg@w3.org > April to June 2017

Re: [dns-privacy] Demultiplexing HTTP and DNS on the same listener [New Version Notification for draft-dkg-dprive-demux-dns-http-02]

From: Roy T. Fielding <fielding@gbiv.com>
Date: Wed, 3 May 2017 12:35:52 -0700
Cc: HTTP Working Group <ietf-http-wg@w3.org>, DNS Privacy Working Group <dns-privacy@ietf.org>
Message-Id: <B0511F40-AA89-47C3-93F2-7A5121F842AA@gbiv.com>
To: Daniel Kahn Gillmor <dkg@fifthhorseman.net>, Joe Touch <touch@ISI.EDU>
> On May 3, 2017, at 11:33 AM, Joe Touch <touch@ISI.EDU> wrote:
> 
> Hi, all,
> 
> FWIW...speaking from the experience I have leading the IANA ports expert
> review team and developing BCP165 (RFCs 6335 and RFC7605):
> 
> On 5/3/2017 11:15 AM, Daniel Kahn Gillmor wrote:
>> And Joe Touch pointed out that the draft should explicitly update the
>> HTTP as well as DNS specifications, so i've marked the latest revision
>> of the draft that way.  If you think that's OK (or if you think it's
>> unnecessary), please let me know!
>> 
>> Assumptions about HTTP
>> ----------------------
> I would characterize this as redefining ports 80 and 443 to include DNS
> as part of the HTTP specification.
> 
> That has some very important ramifications, indicated here as
> "assumptions", that limit the future development of HTTP (notably
> reserving certain prefixes and patterns to differentiate DNS requests
> from HTTP). That could constrain all current and future uses of ports 80
> and 443, and could potentially affect any other service that uses HTTP
> as a framing layer.
> 
> Joe

I agree with Joe.  My answer would be "no".  It certainly isn't an Update
for the HTTP specs.

I see no reason to suggest that spraying DNS on an HTTP connection would
be interoperable.  HTTP/1.x has a tradition (good or bad) of allowing
robust parsing of bad messages, which means no analysis of DNS uniqueness
can guard against the potential variance of a thousand or so independent
implementations of servers and intermediaries (there are at least four
figures of independent server development in the craft-your-own-microserver
category).

In contrast, it is trivial to transform a DNS query into a GET request
which can be handled by any current or future version of HTTP.
All you need is the absolute URI, which is already defined, and a
media type for the response payload.  That would just be using HTTP,
so no need to call that an update either.

....Roy
Received on Wednesday, 3 May 2017 19:36:21 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 17:15:03 UTC