Re: [DNSOP] RFC 8482 (the ANY -> HINFO hack) and DNAME

Viktor Dukhovni <ietf-dane@dukhovni.org> Thu, 14 November 2019 19:31 UTC

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From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [DNSOP] RFC 8482 (the ANY -> HINFO hack) and DNAME
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> On Nov 14, 2019, at 9:40 AM, Shane Kerr <shane@time-travellers.org>; wrote:
> 
> We have chosen to perform CNAME synthesis for ANY queries that match a DNAME subtree, based on the logic that if CNAME is special when added by hand then it is probably also special when synthesized.
> 
> I'm interested in what the DNSOP group thinks the correct behavior is, and also if it makes sense to update RFC 8482 to clarify the expected behavior for DNAME.

With a signed zone, you have no choice but to provide the DNAME,
the closest encloser is the DNAME owner which has "DNAME" in its
type bitmask.

Thus the correct response is:

	example.net. IN DNAME example.org.
	example.net. IN RRSIG DNAME ...
	sub.example.net. IN CNAME sub.example.org. ; synthesized

This can be the entire response with NOERROR as the RCODE.
For a recursive resolver can chase the CNAME as appropriate.

-- 
-- 
	Viktor.