Subject: [dnsext] [Technical Errata Reported] RFC5155 (4622)

From: RFC Errata System <[email-masked]>
Date: Wed, 17 Feb 2016 17:36:20 -0800 (PST)

The following errata report has been submitted for RFC5155,
"DNS Security (DNSSEC) Hashed Authenticated Denial of Existence".

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You may review the report below and at:
http://www.rfc-editor.org/errata_search.php?rfc=5155&eid=4622

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Type: Technical
Reported by: Robert Edmonds <[email-masked]>

Section: 7.2.8

Original Text
-------------
7.2.8.  Responding to Queries for NSEC3 Owner Names

   The owner names of NSEC3 RRs are not represented in the NSEC3 RR
   chain like other owner names.  As a result, each NSEC3 owner name is
   covered by another NSEC3 RR, effectively negating the existence of
   the NSEC3 RR.  This is a paradox, since the existence of an NSEC3 RR
   can be proven by its RRSIG RRSet.

   If the following conditions are all true:

   o  the QNAME equals the owner name of an existing NSEC3 RR, and

   o  no RR types exist at the QNAME, nor at any descendant of QNAME,

   then the response MUST be constructed as a Name Error response
   (Section 7.2.2).  Or, in other words, the authoritative name server
   will act as if the owner name of the NSEC3 RR did not exist.

Corrected Text
--------------
7.2.8.  Responding to Queries for NSEC3 Owner Names

   The owner names of NSEC3 RRs are not represented in the NSEC3 RR
   chain like other owner names.  As a result, each NSEC3 owner name is
   covered by another NSEC3 RR, effectively negating the existence of
   the NSEC3 RR.  This is a paradox, since the existence of an NSEC3 RR
   can be proven by its RRSIG RRSet.

   If the following conditions are all true:

   o  the QNAME equals the owner name of an existing NSEC3 RR, and

   o  no RR types exist at the QNAME besides NSEC3, nor at any
      descendant of QNAME,

   then the response MUST be constructed as a Name Error response
   (Section 7.2.2).  Or, in other words, the authoritative name server
   will act as if the owner name of the NSEC3 RR did not exist.

Notes
-----
If the QNAME is equal to the owner name of an existing NSEC3 RR, then the NSEC3 RR type itself will exist at the QNAME, and the second condition will always be false.

Instructions:
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RFC5155 (draft-ietf-dnsext-nsec3-13)
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Title               : DNS Security (DNSSEC) Hashed Authenticated Denial of Existence
Publication Date    : March 2008
Author(s)           : B. Laurie, G. Sisson, R. Arends, D. Blacka
Category            : PROPOSED STANDARD
Source              : DNS Extensions
Area                : Internet
Stream              : IETF
Verifying Party     : IESG

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From: Brian Haberman <[email-masked]>
Date: Fri, 19 Feb 2016 10:11:25 -0500

Does anyone have an opinion on the validity of this erratum? It seems
like a reasonable clarification in my reading.

Brian

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From: "Blacka, David" <[email-masked]>
Date: Fri, 19 Feb 2016 16:37:47 +0000

> On Feb 19, 2016, at 10:11 AM, Brian Haberman <[email-masked]> wrote:
> 

The clarification looks correct and reasonable to me.

--
David Blacka                          <[email-masked]> 
Distinguished Engineer                Verisign Product Engineering

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From: "Paul Hoffman" <[email-masked]>
Date: Fri, 19 Feb 2016 07:44:47 -0800

> like a reasonable clarification in my reading.

This was discussed on the DNSOP mailing list and folks agreed with the 
clarification.

--Paul Hoffman

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From: Ben Laurie <[email-masked]>
Date: Sat, 20 Feb 2016 20:43:04 +0000

Me, too, though it could be more economically expressed as "no _other_ RR
types exist...".

On 19 February 2016 at 16:37, Blacka, David <[email-masked]> wrote:

> >> If the QNAME is equal to the owner name of an existing NSEC3 RR, then
> the NSEC3 RR type itself will exist at the QNAME, and the second condition
> will always be false.
> >>
> >> Instructions:
> >> -------------