7218
PROPOSED STANDARD

Adding Acronyms to Simplify Conversations about DNS-Based Authentication of Named Entities (DANE)

Authors: O. Gudmundsson
Date: April 2014
Area: sec
Working Group: dane
Stream: IETF
Updates: RFC 6698

Abstract

Experience has shown that people get confused when discussing the three numeric fields of the TLSA record. This document specifies descriptive acronyms for the three numeric fields in TLSA records. This document updates the format of the IANA registry created by RFC 6698.

RFC 7218: Adding Acronyms to Simplify Conversations about DNS-Based Authentication of Named Entities (DANE) [RFC Home] [TEXT|PDF|HTML] [Tracker] [IPR] [Info page]

PROPOSED STANDARD
Internet Engineering Task Force (IETF)                    O. Gudmundsson
Request for Comments: 7218                                 Shinkuro Inc.
Updates: <a href="./rfc6698">6698</a>                                                 April 2014
Category: Standards Track
ISSN: 2070-1721


            <span class="h1">Adding Acronyms to Simplify Conversations about</span>
           <span class="h1">DNS-Based Authentication of Named Entities (DANE)</span>

Abstract

   Experience has shown that people get confused when discussing the
   three numeric fields of the TLSA record.  This document specifies
   descriptive acronyms for the three numeric fields in TLSA records.
   This document updates the format of the IANA registry created by <a href="./rfc6698">RFC</a>
   <a href="./rfc6698">6698</a>.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in <a href="./rfc5741#section-2">Section 2 of RFC 5741</a>.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   <a href="https://www.rfc-editor.org/info/rfc7218">http://www.rfc-editor.org/info/rfc7218</a>.

Copyright Notice

   Copyright (c) 2014 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to <a href="https://www.rfc-editor.org/bcp/bcp78">BCP 78</a> and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (<a href="http://trustee.ietf.org/license-info">http://trustee.ietf.org/license-info</a>) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.





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Table of Contents

   <a href="#section-1">1</a>.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   <a href="#page-2">2</a>
   <a href="#section-2">2</a>.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   <a href="#page-2">2</a>
     <a href="#section-2.1">2.1</a>.  TLSA Certificate Usages Registry  . . . . . . . . . . . .   <a href="#page-3">3</a>
     <a href="#section-2.2">2.2</a>.  TLSA Selectors  . . . . . . . . . . . . . . . . . . . . .   <a href="#page-3">3</a>
     <a href="#section-2.3">2.3</a>.  TLSA Matching Types . . . . . . . . . . . . . . . . . . .   <a href="#page-4">4</a>
   <a href="#section-3">3</a>.  Examples of Usage . . . . . . . . . . . . . . . . . . . . . .   <a href="#page-4">4</a>
     <a href="#section-3.1">3.1</a>.  TLSA Records Using/Displaying the Acronyms  . . . . . . .   <a href="#page-4">4</a>
     <a href="#section-3.2">3.2</a>.  Acronym Use in a Specification Example  . . . . . . . . .   <a href="#page-4">4</a>
   <a href="#section-4">4</a>.  Security Considerations . . . . . . . . . . . . . . . . . . .   <a href="#page-4">4</a>
   <a href="#section-5">5</a>.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   <a href="#page-4">4</a>
   <a href="#section-6">6</a>.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   <a href="#page-5">5</a>
     <a href="#section-6.1">6.1</a>.  Normative References  . . . . . . . . . . . . . . . . . .   <a href="#page-5">5</a>
     <a href="#section-6.2">6.2</a>.  Informative References  . . . . . . . . . . . . . . . . .   <a href="#page-5">5</a>

<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>.  Introduction</span>

   During discussions on how to add DNS-Based Authentication of Named
   Entities (DANE) [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>] technology to new protocols and services,
   people were repeatedly confused as to what the numeric values stood
   for and even the order of the fields of a TLSA record (note that TLSA
   is not an acronym but a name).  This document updates the IANA
   registry definition for the TLSA record to add a column containing an
   acronym for each specified field, in order to reduce confusion.  This
   document does not change the DANE protocol in any way.

   It is expected that DANE parsers in applications and DNS software can
   adopt parsing the acronyms for each field.

<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>.  IANA Considerations</span>

   This document applies to the "DNS-Based Authentication of Named
   Entities (DANE) Parameters" registry located at <<a href="http://www.iana.org/assignments/dane-parameters">http://www.iana.org/</a>
   <a href="http://www.iana.org/assignments/dane-parameters">assignments/dane-parameters</a>>.  IANA has added a column with an
   acronym to each of the sub-registries.

   [<a id="ref-RFC6698">RFC6698</a>] and this document are the referenced documents for the
   three sub-registries.

   As these acronyms are offered for human consumption, case does not
   matter; it is expected that software that parses TLSA records will
   handle upper-, mixed-, or lower-case characters as input.








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<span class="h3"><a class="selflink" id="section-2.1" href="#section-2.1">2.1</a>.  TLSA Certificate Usages Registry</span>

   The reference for this registry has been updated to include both
   [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>] and this document.

    +-------+----------+--------------------------------+-------------+
    | Value | Acronym  | Short Description              | Reference   |
    +-------+----------+--------------------------------+-------------+
    |   0   | PKIX-TA  | CA constraint                  | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
    |   1   | PKIX-EE  | Service certificate constraint | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
    |   2   | DANE-TA  | Trust anchor assertion         | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
    |   3   | DANE-EE  | Domain-issued certificate      | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
    | 4-254 |          | Unassigned                     |             |
    |  255  | PrivCert | Reserved for Private Use       | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
    +-------+----------+--------------------------------+-------------+

                     Table 1: TLSA Certificate Usages

<span class="h3"><a class="selflink" id="section-2.2" href="#section-2.2">2.2</a>.  TLSA Selectors</span>

   The reference for this registry has been updated to include both
   [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>] and this document.

       +-------+---------+--------------------------+-------------+
       | Value | Acronym | Short Description        | Reference   |
       +-------+---------+--------------------------+-------------+
       |   0   | Cert    | Full certificate         | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
       |   1   | SPKI    | SubjectPublicKeyInfo     | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
       | 2-254 |         | Unassigned               |             |
       |  255  | PrivSel | Reserved for Private Use | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
       +-------+---------+--------------------------+-------------+

                          Table 2: TLSA Selectors


















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<span class="h3"><a class="selflink" id="section-2.3" href="#section-2.3">2.3</a>.  TLSA Matching Types</span>

   The reference for this registry has been updated to include both
   [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>] and this document.

      +-------+-----------+--------------------------+-------------+
      | Value | Acronym   | Short Description        | Reference   |
      +-------+-----------+--------------------------+-------------+
      |   0   | Full      | No hash used             | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
      |   1   | SHA2-256  | 256 bit hash by SHA2     | [<a href="./rfc6234" title=""US Secure Hash Algorithms (SHA and SHA-based HMAC and HKDF)"">RFC6234</a>]   |
      |   2   | SHA2-512  | 512 bit hash by SHA2     | [<a href="./rfc6234" title=""US Secure Hash Algorithms (SHA and SHA-based HMAC and HKDF)"">RFC6234</a>]   |
      | 3-254 |           | Unassigned               |             |
      |  255  | PrivMatch | Reserved for Private Use | [<a href="./rfc6698" title=""The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA"">RFC6698</a>]   |
      +-------+-----------+--------------------------+-------------+

                       Table 3: TLSA Matching Types

<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>.  Examples of Usage</span>

   Two examples are described below.

<span class="h3"><a class="selflink" id="section-3.1" href="#section-3.1">3.1</a>.  TLSA Records Using/Displaying the Acronyms</span>

   _666._tcp.first.example.  TLSA PKIX-TA CERT SHA2-512 {blob}
   _666._tcp.second.example.  TLSA DANE-TA SPKI SHA2-256 {blob}

<span class="h3"><a class="selflink" id="section-3.2" href="#section-3.2">3.2</a>.  Acronym Use in a Specification Example</span>

   Protocol FOO only allows TLSA records using PKIX-EE and DANE-EE, with
   selector SPKI, and using SHA2-512.

<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>.  Security Considerations</span>

   This document only changes registry fields and does not change the
   behavior of any protocol.  The hope is to reduce confusion, which
   would lead to better specification and operations.

<span class="h2"><a class="selflink" id="section-5" href="#section-5">5</a>.  Acknowledgements</span>

   Scott Schmit offered really good suggestions to decrease the
   possibility of confusion.  Viktor Dukhovni provided comments from the
   expert point of view.  Jim Schaad, Wes Hardaker, and Paul Hoffman
   provided feedback during WGLC.  Dan Romascanu and Tobias Gondrom
   pointed out a few defects during the IESG last call.







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<span class="h2"><a class="selflink" id="section-6" href="#section-6">6</a>.  References</span>

<span class="h3"><a class="selflink" id="section-6.1" href="#section-6.1">6.1</a>.  Normative References</span>

   [<a id="ref-RFC6698">RFC6698</a>]  Hoffman, P. and J. Schlyter, "The DNS-Based Authentication
              of Named Entities (DANE) Transport Layer Security (TLS)
              Protocol: TLSA", <a href="./rfc6698">RFC 6698</a>, August 2012.

<span class="h3"><a class="selflink" id="section-6.2" href="#section-6.2">6.2</a>.  Informative References</span>

   [<a id="ref-RFC6234">RFC6234</a>]  Eastlake, D. and T. Hansen, "US Secure Hash Algorithms
              (SHA and SHA-based HMAC and HKDF)", <a href="./rfc6234">RFC 6234</a>, May 2011.

Author's Address

   Olafur Gudmundsson
   Shinkuro Inc.
   4922 Fairmont Av, Suite 250
   Bethesda, MD  20814
   USA

   EMail: [email protected]





























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