Internet Engineering Task Force (IETF)                           S. Rose
Request for Comments: 6725                                          NIST
Category: Standards Track                                    August 2012
ISSN: 2070-1721

      DNS Security (DNSSEC) DNSKEY Algorithm IANA Registry Updates

Abstract

   The DNS Security Extensions (DNSSEC) require the use of cryptographic
   algorithm suites for generating digital signatures over DNS data.
   The algorithms specified for use with DNSSEC are reflected in an
   IANA-maintained registry.  This document presents a set of changes
   for some entries of the registry.

Status of This Memo

   This is an Internet Standards Track document.

Table of Contents

   1. Introduction ....................................................2
   2. The DNS Security Algorithm Numbers Sub-Registry .................2
      2.1. Updates and Additions ......................................2
      2.2. DNS Security Algorithm Numbers Sub-Registry Table ..........3
   3. IANA Considerations .............................................4
   4. Security Considerations .........................................4
   5. Informative References ..........................................4

1.  Introduction

   The Domain Name System (DNS) Security Extensions (DNSSEC, defined by
   [RFC4033], [RFC4034], [RFC4035], [RFC4509], [RFC5155], and [RFC5702])
   use digital signatures over DNS data to provide source authentication
   and integrity protection.  DNSSEC uses an IANA registry to list codes
   for digital signature algorithms (consisting of an asymmetric
   cryptographic algorithm and a one-way hash function).

   This document updates a set of entries in the IANA registry titled
   "DNS Security (DNSSEC) Algorithm Numbers".  These updated entries are
   given in Section 2.2 below.  This list includes changes to selected
   entries originally set aside for future algorithm specification that
   did not occur.  These three entries are changed to "Reserved" to
   avoid potential conflicts with older implementations.  This document
   also brings the list of references for entries up to date.

   There are auxiliary sub-registries related to the DNS Security
   (DNSSEC) Algorithm Numbers registry that deal with various Diffie-
   Hellman parameters used with DNSSEC.  These registry tables are not
   altered by this document.

2.  The DNS Security Algorithm Numbers Sub-Registry

   The DNS Security Algorithm Numbers sub-registry (part of the Domain
   Name System Security (DNSSEC) Algorithm Numbers registry) contains a
   set of entries that contain errors.  There are additional differences
   to entries that are described in Section 2.1, and the complete list
   of changed registry entries is in Section 2.2.

2.1.  Updates and Additions

   This document updates three entries in the Domain Name System
   Security (DNSSEC) Algorithm Numbers registry:

   The description for assignment number 4 is changed to "Reserved".

   The description for assignment number 9 is changed to "Reserved".

   The description for assignment number 11 is changed to "Reserved".

   The above entries are changed to "Reserved" because they were
   placeholders for algorithms that were not fully specified for use
   with DNSSEC.  Older implementations may still have these algorithm
   codes assigned, so these codes are reserved to prevent potential
   incompatibilities.

2.2.  DNS Security Algorithm Numbers Sub-Registry Table

   The list of DNS Security Algorithm Numbers sub-registry entry changes
   is given below.  All other existing entries in the sub-registry table
   are unchanged by this document and are not shown.  The other two
   sub-registries in the Domain Name System Security (DNSSEC) Algorithm
   Numbers registry (DNS KEY Record Diffie-Hellman Prime Lengths and DNS
   KEY Record Diffie-Hellman Well-Known Prime/Generator Pairs) are not
   changed in any way by this document.

                                          Zone     Trans.
    Number  Description       Mnemonic   Signing   Sec.       Reference
    ------  -----------       --------   -------   ---------  ---------
      0      Reserved                                         [RFC4034],
                                                              [RFC4398]

      1      RSA/MD5          RSAMD5        N         Y       [RFC3110],
             (deprecated;                                     [RFC4034]
             see 5)

      4      Reserved                                         [RFC6725]

      5      RSA/SHA-1        RSASHA1       Y         Y       [RFC3110],
                                                              [RFC4034]

      9      Reserved                                         [RFC6725]

     11      Reserved                                         [RFC6725]

   15-122    Unassigned

   123-251   Reserved                                         [RFC4034],
                                                              [RFC6014]

     253     private          PRIVATEDNS    Y         Y       [RFC4034]
             algorithm

     254     private          PRIVATEOID    Y         Y       [RFC4034]
             algorithm OID

3.  IANA Considerations

   This document updates a set of DNS Security Algorithm Numbers
   sub-registry entries as given in Section 2.2.  The changes include
   moving three registry entries to "Reserved" and updating the
   reference list for entries.

4.  Security Considerations

   This document updates the Domain Name System Security (DNSSEC)
   Algorithm Numbers registry.  It is not meant to be a discussion on
   algorithm superiority.  No new security considerations are raised in
   this document.

5.  Informative References

   [RFC3110]  Eastlake, D., "RSA/SHA-1 SIGs and RSA KEYs in the Domain
              Name System (DNS)", RFC 3110, May 2001.

   [RFC4033]  Arends, R., Austein, R., Larson, M., Massey, D., and S.
              Rose, "DNS Security Introduction and Requirements",
              RFC 4033, March 2005.

   [RFC4034]  Arends, R., Austein, R., Larson, M., Massey, D., and S.
              Rose, "Resource Records for the DNS Security Extensions",
              RFC 4034, March 2005.

   [RFC4035]  Arends, R., Austein, R., Larson, M., Massey, D., and S.
              Rose, "Protocol Modifications for the DNS Security
              Extensions", RFC 4035, March 2005.

   [RFC4398]  Josefsson, S., "Storing Certificates in the Domain Name
              System (DNS)", RFC 4398, March 2006.

   [RFC4509]  Hardaker, W., "Use of SHA-256 in DNSSEC Delegation Signer
              (DS) Resource Records (RRs)", RFC 4509, May 2006.

   [RFC5155]  Laurie, B., Sisson, G., Arends, R., and D. Blacka, "DNS
              Security (DNSSEC) Hashed Authenticated Denial of
              Existence", RFC 5155, March 2008.

   [RFC5702]  Jansen, J., "Use of SHA-2 Algorithms with RSA in DNSKEY
              and RRSIG Resource Records for DNSSEC", RFC 5702,
              October 2009.

   [RFC6014]  Hoffman, P., "Cryptographic Algorithm Identifier
              Allocation for DNSSEC", RFC 6014, November 2010.

Author's Address

   Scott Rose
   NIST
   100 Bureau Dr.
   Gaithersburg, MD  20899
   USA

   Phone: +1-301-975-8439
   EMail: scottr.nist@gmail.com