RFC 5748 INFORMATIONAL SECURITY · REGISTRY · CRYPTOGRAPHY

IANA Registry Update for Support of the SEED Cipher Algorithm in Multimedia Internet KEYing (MIKEY)

Registers code points so the SEED cipher can be negotiated for SRTP and SRTCP in MIKEY.

On rfc-editor.org ↗
PUBLISHED
August 2010
AUTHORS
S. Yoon, J. Jeong, H. Kim, H. Jeong, Y. Won
STREAM
IETF
SEED BLOCK SIZE
128 bits
SEED KEY LENGTH
128 bits
SEED STRUCTURE
16-round Feistel
NEW SRTP ENCRYPTION VALUES
SEED-CTR 3, SEED-CCM 4, SEED-GCM 5
NEW SRTP PRF VALUE
SEED-CTR 1
DOI
10.17487/RFC5748
ERRATA
Reported errata

RFC text

Contents
Original text · RFC Editor View on rfc-editor.org ↗
Internet Engineering Task Force (IETF)                          J. Jeong
Request for Comments: 5748                                        H. Kim
Category: Informational                                         H. Jeong
ISSN: 2070-1721                                                   Y. Won
                                        Korea Internet & Security Agency
                                                             August 2010


    IANA Registry Update for Support of the SEED Cipher Algorithm in
                   Multimedia Internet KEYing (MIKEY)

Abstract

   This document updates IANA registries to support the SEED block
   cipher algorithm for the Secure Real-time Transport Protocol (SRTP)
   and the secure Real-time Transport Control Protocol (SRTCP) in
   Multimedia Internet KEYing (MIKEY).

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   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).  Not all documents
   approved by the IESG are a candidate for any level of Internet
   Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc5748.

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) 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.

Table of Contents

   1. Introduction ....................................................2
      1.1. SEED .......................................................2
   2. Additions to MIKEY Payload ......................................2
      2.1. Modified Table 6.10.1.b from RFC 3830 ......................3
      2.2. Modified Table 6.10.1.d from RFC 3830 ......................3
   3. Security Considerations .........................................3
   4. IANA Considerations .............................................3
   5. Acknowledgements ................................................3
   6. References ......................................................4
      6.1. Normative References .......................................4
      6.2. Informative References .....................................4

1.  Introduction

   This document updates IANA registries to support the SEED [RFC4269]
   block cipher algorithm for the Secure Real-time Transport Protocol
   (SRTP) and the Secure Real-time Transport Control Protocol (SRTCP)
   [RFC3711] in Multimedia Internet KEYing (MIKEY) [RFC3830].

1.1.  SEED

   SEED is a 128-bit symmetric key block cipher that has been developed
   by KISA (Korea Information Security Agency) and a group of experts
   since 1998.  The input/output block size of SEED is 128-bit, and the
   key length is also 128-bit.  SEED has a 16-round Feistel structure.

   SEED is a Korean National Industrial Association standard and is
   widely used in South Korea for electronic commerce and various
   security products such as firewalls, VPNs, and so on.

2.  Additions to MIKEY Payload

   This section specifies new code points for the MIKEY [RFC3830]
   payload to indicate the use of the SEED cipher algorithm for SRTP and
   SRTCP.  There are three applicable modes of running SEED: SEED in
   Counter Mode (SEED-CTR), SEED in Counter with CBC-MAC Mode (SEED-
   CCM), and SEED in Galois/Counter Mode (SEED-GCM) Mode.  These are
   defined in [RFC5669].

2.1.  Modified Table 6.10.1.b from RFC 3830

   IANA has amended the sub-registry derived from Table 6.10.1.b of
   [RFC3830] as follows:

               SRTP encr alg | Value
               ---------------------
               NULL          |     0
               AES-CM        |     1
               AES-F8        |     2
               SEED-CTR      |     3 (NEW)
               SEED-CCM      |     4 (NEW)
               SEED-GCM      |     5 (NEW)

             Figure 1: Table 6.10.1.b from [RFC3830] (Revised)

2.2.  Modified Table 6.10.1.d from RFC 3830

   IANA has amended the sub-registry derived from Table 6.10.1.d of
   [RFC3830] as follows:

               SRTP PRF      | Value
               ---------------------
               AES-CM        |     0
               SEED-CTR      |     1 (NEW)

             Figure 2: Table 6.10.1.d from [RFC3830] (Revised)

3.  Security Considerations

   No security problem has been found on SEED.  SEED is secure against
   all known attacks including differential cryptanalysis, linear
   cryptanalysis, and related key attacks.  The only known attack is an
   exhaustive search for the key.  For further security considerations,
   the reader is encouraged to read [SEED-EVAL].

4.  IANA Considerations

   IANA has amended the indicated sub-registries in Section 2 of the
   MIKEY [RFC3830] Payload Name registry according to Sections 2.1 and
   2.2 above.

5.  Acknowledgements

   The authors would like to thank David McGrew, Spencer Dawkins,
   SangHwan Park, Brian Weis, and Tim Polk for their reviews and
   support.

6.  References

6.1.  Normative References

   [RFC3711]   Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K.
               Norrman, "The Secure Real-time Transport Protocol
               (SRTP)", RFC 3711, March 2004.

   [RFC3830]   Arkko, J., Carrara, E., Lindholm, F., Naslund, M., and K.
               Norrman, "MIKEY: Multimedia Internet KEYing", RFC 3830,
               August 2004.

   [RFC4269]   Lee, H., Lee, S., Yoon, J., Cheon, D., and J. Lee, "The
               SEED Encryption Algorithm", RFC 4269, December 2005.

   [RFC5669]   Yoon, S., Kim, J., Park, H., Jeong, H., and Y. Won, "The
               SEED Cipher Algorithm and Its Use with the Secure Real-
               Time Transport Protocol (SRTP)", RFC 5669, August 2010.

6.2.  Informative References

   [SEED-EVAL] KISA, "Self Evaluation Report",
               http://seed.kisa.or.kr/eng/main.jsp

Authors' Addresses

   Seokung Yoon
   Korea Internet & Security Agency
   IT Venture Tower, Jungdaero 135, Songpa-gu
   Seoul, Korea 138-950
   EMail: seokung@kisa.or.kr

   Jongil Jeong
   Korea Internet & Security Agency
   IT Venture Tower, Jungdaero 135, Songpa-gu
   Seoul, Korea 138-950
   EMail: jijeong@kisa.or.kr

   Hwankuk Kim
   Korea Internet & Security Agency
   IT Venture Tower, Jungdaero 135, Songpa-gu
   Seoul, Korea 138-950
   EMail: rinyfeel@kisa.or.kr

   Hyuncheol Jeong
   Korea Internet & Security Agency
   IT Venture Tower, Jungdaero 135, Songpa-gu
   Seoul, Korea 138-950
   EMail: hcjung@kisa.or.kr

   Yoojae Won
   Korea Internet & Security Agency
   IT Venture Tower, Jungdaero 135, Songpa-gu
   Seoul, Korea 138-950
   EMail: yjwon@kisa.or.kr

AI ELI5

On this page
PROBLEMMIKEY, the key management protocol for SRTP, had no code points to say that the SEED block cipher is in use.
MECHANISMIANA amended two MIKEY sub-registries: three SEED modes (SEED-CTR, SEED-CCM, SEED-GCM) were added as encryption algorithms, and SEED-CTR was added as a pseudo-random function.
WHY IT MATTERSEndpoints can now signal SEED in MIKEY. The document changes registry values only and defines no new protocol.

§1Introduction and the SEED Cipher

RFC 5748 updates IANA registries to support the SEED block cipher for the Secure Real-time Transport Protocol (SRTP) and the Secure Real-time Transport Control Protocol (SRTCP) in Multimedia Internet KEYing (MIKEY, RFC 3830).

SEED is a 128-bit symmetric key block cipher developed by KISA (Korea Information Security Agency) and a group of experts since 1998. Its block size and key length are both 128 bits, and it has a 16-round Feistel structure. The RFC says it is a Korean National Industrial Association standard and is widely used in South Korea for electronic commerce and security products such as firewalls and VPNs.

SEED is a secret-code recipe from Korea. This note tells the key-sharing system that the recipe exists.

§2New MIKEY Payload Code Points

The RFC specifies new code points in the MIKEY payload to indicate SEED for SRTP and SRTCP. There are three modes of running SEED, defined in RFC 5669: SEED-CTR (Counter Mode), SEED-CCM (Counter with CBC-MAC Mode) and SEED-GCM (Galois/Counter Mode).

In the table derived from Table 6.10.1.b of RFC 3830 (SRTP encryption algorithm), the existing values are NULL 0, AES-CM 1 and AES-F8 2. The new values are SEED-CTR 3, SEED-CCM 4 and SEED-GCM 5. In the table derived from Table 6.10.1.d (SRTP PRF), AES-CM is 0 and SEED-CTR is the new value 1.

Each cipher gets a number on a menu. SEED gets three new numbers for its three ways of working, and one more on a second menu.

SRTP ENCRYPTION ALGORITHM VALUES (TABLE 6.10.1.B, REVISED)
  • 0NULL — Existing value.
  • 1AES-CM — Existing value.
  • 2AES-F8 — Existing value.
  • 3SEED-CTR — New: SEED in Counter Mode.
  • 4SEED-CCM — New: SEED in Counter with CBC-MAC Mode.
  • 5SEED-GCM — New: SEED in Galois/Counter Mode.

§3Security and IANA Actions

The security section says no security problem has been found on SEED. It states that SEED is secure against all known attacks including differential cryptanalysis, linear cryptanalysis and related key attacks, and that the only known attack is an exhaustive search for the key. It points readers to the KISA self evaluation report for more.

IANA has amended the indicated sub-registries in the MIKEY Payload Name registry as described above.

The authors say nobody has found a way to break the recipe except by trying every key. The librarians have written the new numbers in the list.

§4References