Re: [DNSOP] Where in a CNAME chain is the QNAME?

"Paul Hoffman" <paul.hoffman@vpnc.org> Thu, 29 September 2016 14:36 UTC

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From: "Paul Hoffman" <paul.hoffman@vpnc.org>
To: "Robert Edmonds" <edmonds@mycre.ws>
Date: Thu, 29 Sep 2016 07:36:16 -0700
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Subject: Re: [DNSOP] Where in a CNAME chain is the QNAME?
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On 28 Sep 2016, at 22:50, Robert Edmonds wrote:

> Stephane Bortzmeyer wrote:
>> On Mon, Sep 26, 2016 at 09:04:54AM -0400,
>>  Matt Larson <matt@kahlerlarson.org> wrote
>>  a message of 41 lines which said:
>>
>>> I'd venture that more people familiar with the subject matter would
>>> define QNAME as the name in the question section of a DNS message.
>>> (That's my sense of the definition, FWIW.)
>>
>> What about adding this text to the Terminology section of the draft?
>>
>>    <t>"QNAME": it is defined in <xref target="RFC1034"/> and
>>    in <xref target="RFC1035"/>, section 4.1.2, but, because <xref
>>    target="RFC2308"/> provides a different definition, we repeat the
>>    original one here: the QNAME is the owner name of the record in 
>> the
>>    Question section.</t>
>
> The QNAME is a domain name, but is it an owner name? There is no owned
> record data in the question section (and the entries in the question
> section are not RRs).

Oddly, "owner name" is correct here. From RFC 1035, Section 3.2.1 which 
describes the format of resource records:

All RRs have the same top level format shown below:

                                     1  1  1  1  1  1
       0  1  2  3  4  5  6  7  8  9  0  1  2  3  4  5
     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
     |                                               |
     /                                               /
     /                      NAME                     /
     |                                               |
     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
     |                      TYPE                     |
     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
. . .

where:

NAME            an owner name, i.e., the name of the node to which this
                 resource record pertains.
. . .

And I think that Stephane's new definition text is a good addition to 
the draft.

--Paul Hoffman