Re: [Doh] [Ext] A question on the mix of DNS and HTTP semantics

Stephane Bortzmeyer <bortzmeyer@nic.fr> Mon, 19 March 2018 15:40 UTC

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Date: Mon, 19 Mar 2018 15:39:58 +0000
From: Stephane Bortzmeyer <bortzmeyer@nic.fr>
To: Andrew Sullivan <ajs@anvilwalrusden.com>
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Subject: Re: [Doh] [Ext] A question on the mix of DNS and HTTP semantics
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On Mon, Mar 19, 2018 at 11:21:27AM -0400,
 Andrew Sullivan <ajs@anvilwalrusden.com> wrote 
 a message of 29 lines which said:

> If it were actually truncated, wouldn't the message have a TC bit
> set?

Truncated for HTTP reasons (error 500 : the server crashed), not for
DNS reasons.

If the DNS answer is truncated for DNS reasons (EDNS buffer size too
small), I would expect the HTTP status code to be 200.