Re: [DNSOP] draft-ietf-dnsop-extended-error code options

Ray Bellis <ray@bellis.me.uk> Mon, 13 November 2017 13:17 UTC

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To: Tony Finch <dot@dotat.at>
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From: Ray Bellis <ray@bellis.me.uk>
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Date: Mon, 13 Nov 2017 21:16:57 +0800
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Subject: Re: [DNSOP] draft-ietf-dnsop-extended-error code options
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On 13/11/2017 21:13, Tony Finch wrote:
> Ray Bellis <ray@bellis.me.uk> wrote:
>> 
>> Would it be feasible to reserve a standard RCODE value in the
>> header that just means "see extended error"?
> 
> That would require client-to-server signalling,

It would.  Perhaps the *request* RCODE could contain the same value to
signal acceptance of the extended version in the response ?

> and the server would be unable to simply unconditionally include the
> extended error in the OPT record.
> 
> There can only be an EDNS RCODE if the client sent an EDNS OPT; if
> the client forgot it sent the OPT then it's too broken to worry
> about.

Indeed - unsolicited EDNS OPT RRs aren't legal in responses.

Ray