Internet Engineering Task Force (IETF)                            W. Kim
Request for Comments: 6209                                        J. Lee
Category: Informational                                          J. Park
ISSN: 2070-1721                                                  D. Kwon
                                                                    NSRI
                                                              April 2011


  Addition of the ARIA Cipher Suites to Transport Layer Security (TLS)

Abstract

   This document specifies a set of cipher suites for the Transport
   Layer Security (TLS) protocol to support the ARIA encryption
   algorithm as a block cipher.

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/rfc6209.

Copyright Notice

   Copyright (c) 2011 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
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   publication of this document.  Please review these documents
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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . 2
     1.1.  ARIA  . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
     1.2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3
   2.  Proposed Cipher Suites  . . . . . . . . . . . . . . . . . . . . 3
     2.1.  HMAC-Based Cipher Suites  . . . . . . . . . . . . . . . . . 3
     2.2.  GCM-Based Cipher Suites . . . . . . . . . . . . . . . . . . 3
     2.3.  PSK Cipher Suites . . . . . . . . . . . . . . . . . . . . . 4
   3.  Cipher Suite Definitions  . . . . . . . . . . . . . . . . . . . 5
     3.1.  Key Exchange  . . . . . . . . . . . . . . . . . . . . . . . 5
     3.2.  Cipher  . . . . . . . . . . . . . . . . . . . . . . . . . . 5
     3.3.  PRFs  . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
     3.4.  PSK Cipher Suites . . . . . . . . . . . . . . . . . . . . . 5
   4.  Security Considerations . . . . . . . . . . . . . . . . . . . . 5
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . . . 7
     6.1.  Normative References  . . . . . . . . . . . . . . . . . . . 7
     6.2.  Informative References  . . . . . . . . . . . . . . . . . . 8

1.  Introduction

   This document specifies cipher suites for the Transport Layer
   Security (TLS) [RFC5246] protocol to support the ARIA [RFC5794]
   encryption algorithm as a block cipher algorithm.  The cipher suites
   include variants using the SHA-2 family of cryptographic hash
   functions and ARIA Galois counter mode.  Elliptic curve cipher suites
   and pre-shared key (PSK) cipher suites are also defined.

   The cipher suites with SHA-1 are not included in this document.  Due
   to recent analytic work on SHA-1 [Wang05], the IETF is gradually
   moving away from SHA-1 and towards stronger hash algorithms.

1.1.  ARIA

   ARIA is a general-purpose block cipher algorithm developed by Korean
   cryptographers in 2003.  It is an iterated block cipher with 128-,
   192-, and 256-bit keys and encrypts 128-bit blocks in 12, 14, and 16
   rounds, depending on the key size.  It is secure and suitable for
   most software and hardware implementations on 32-bit and 8-bit
   processors.  It was established as a Korean standard block cipher
   algorithm in 2004 [ARIAKS] and has been widely used in Korea,
   especially for government-to-public services.  It was included in
   PKCS #11 in 2007 [ARIAPKCS].  The algorithm specification and object
   identifiers are described in [RFC5794].

1.2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.  Proposed Cipher Suites

2.1.  HMAC-Based Cipher Suites

   The first twenty cipher suites use ARIA [RFC5794] in Cipher Block
   Chaining (CBC) mode with a SHA-2 family Hashed Message Authentication
   Code (HMAC).  Eight out of twenty use elliptic curves.

   CipherSuite TLS_RSA_WITH_ARIA_128_CBC_SHA256         = { 0xC0,0x3C };
   CipherSuite TLS_RSA_WITH_ARIA_256_CBC_SHA384         = { 0xC0,0x3D };
   CipherSuite TLS_DH_DSS_WITH_ARIA_128_CBC_SHA256      = { 0xC0,0x3E };
   CipherSuite TLS_DH_DSS_WITH_ARIA_256_CBC_SHA384      = { 0xC0,0x3F };
   CipherSuite TLS_DH_RSA_WITH_ARIA_128_CBC_SHA256      = { 0xC0,0x40 };
   CipherSuite TLS_DH_RSA_WITH_ARIA_256_CBC_SHA384      = { 0xC0,0x41 };
   CipherSuite TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x42 };
   CipherSuite TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x43 };
   CipherSuite TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x44 };
   CipherSuite TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x45 };
   CipherSuite TLS_DH_anon_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x46 };
   CipherSuite TLS_DH_anon_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x47 };

   CipherSuite TLS_ECDHE_ECDSA_WITH_ARIA_128_CBC_SHA256 = { 0xC0,0x48 };
   CipherSuite TLS_ECDHE_ECDSA_WITH_ARIA_256_CBC_SHA384 = { 0xC0,0x49 };
   CipherSuite TLS_ECDH_ECDSA_WITH_ARIA_128_CBC_SHA256  = { 0xC0,0x4A };
   CipherSuite TLS_ECDH_ECDSA_WITH_ARIA_256_CBC_SHA384  = { 0xC0,0x4B };
   CipherSuite TLS_ECDHE_RSA_WITH_ARIA_128_CBC_SHA256   = { 0xC0,0x4C };
   CipherSuite TLS_ECDHE_RSA_WITH_ARIA_256_CBC_SHA384   = { 0xC0,0x4D };
   CipherSuite TLS_ECDH_RSA_WITH_ARIA_128_CBC_SHA256    = { 0xC0,0x4E };
   CipherSuite TLS_ECDH_RSA_WITH_ARIA_256_CBC_SHA384    = { 0xC0,0x4F };

2.2.  GCM-Based Cipher Suites

   The next twenty cipher suites use the same asymmetric algorithms as
   those in the previous section but use the authenticated encryption
   modes defined in TLS 1.2 with the ARIA in Galois Counter Mode (GCM)
   [GCM].

   CipherSuite TLS_RSA_WITH_ARIA_128_GCM_SHA256         = { 0xC0,0x50 };
   CipherSuite TLS_RSA_WITH_ARIA_256_GCM_SHA384         = { 0xC0,0x51 };
   CipherSuite TLS_DHE_RSA_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x52 };
   CipherSuite TLS_DHE_RSA_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x53 };
   CipherSuite TLS_DH_RSA_WITH_ARIA_128_GCM_SHA256      = { 0xC0,0x54 };
   CipherSuite TLS_DH_RSA_WITH_ARIA_256_GCM_SHA384      = { 0xC0,0x55 };
   CipherSuite TLS_DHE_DSS_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x56 };
   CipherSuite TLS_DHE_DSS_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x57 };
   CipherSuite TLS_DH_DSS_WITH_ARIA_128_GCM_SHA256      = { 0xC0,0x58 };
   CipherSuite TLS_DH_DSS_WITH_ARIA_256_GCM_SHA384      = { 0xC0,0x59 };
   CipherSuite TLS_DH_anon_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x5A };
   CipherSuite TLS_DH_anon_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x5B };

   CipherSuite TLS_ECDHE_ECDSA_WITH_ARIA_128_GCM_SHA256 = { 0xC0,0x5C };
   CipherSuite TLS_ECDHE_ECDSA_WITH_ARIA_256_GCM_SHA384 = { 0xC0,0x5D };
   CipherSuite TLS_ECDH_ECDSA_WITH_ARIA_128_GCM_SHA256  = { 0xC0,0x5E };
   CipherSuite TLS_ECDH_ECDSA_WITH_ARIA_256_GCM_SHA384  = { 0xC0,0x5F };
   CipherSuite TLS_ECDHE_RSA_WITH_ARIA_128_GCM_SHA256   = { 0xC0,0x60 };
   CipherSuite TLS_ECDHE_RSA_WITH_ARIA_256_GCM_SHA384   = { 0xC0,0x61 };
   CipherSuite TLS_ECDH_RSA_WITH_ARIA_128_GCM_SHA256    = { 0xC0,0x62 };
   CipherSuite TLS_ECDH_RSA_WITH_ARIA_256_GCM_SHA384    = { 0xC0,0x63 };

2.3.  PSK Cipher Suites

   The next fourteen cipher suites describe PSK cipher suites.  Eight
   cipher suites use an HMAC and six cipher suites use the ARIA Galois
   Counter Mode.

   CipherSuite TLS_PSK_WITH_ARIA_128_CBC_SHA256         = { 0xC0,0x64 };
   CipherSuite TLS_PSK_WITH_ARIA_256_CBC_SHA384         = { 0xC0,0x65 };
   CipherSuite TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x66 };
   CipherSuite TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x67 };
   CipherSuite TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x68 };
   CipherSuite TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x69 };
   CipherSuite TLS_PSK_WITH_ARIA_128_GCM_SHA256         = { 0xC0,0x6A };
   CipherSuite TLS_PSK_WITH_ARIA_256_GCM_SHA384         = { 0xC0,0x6B };
   CipherSuite TLS_DHE_PSK_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x6C };
   CipherSuite TLS_DHE_PSK_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x6D };
   CipherSuite TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x6E };
   CipherSuite TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x6F };
   CipherSuite TLS_ECDHE_PSK_WITH_ARIA_128_CBC_SHA256   = { 0xC0,0x70 };
   CipherSuite TLS_ECDHE_PSK_WITH_ARIA_256_CBC_SHA384   = { 0xC0,0x71 };

3.  Cipher Suite Definitions

3.1.  Key Exchange

   The RSA, DHE_RSA, DH_RSA, DHE_DSS, DH_DSS, DH_anon, ECDH, and ECDHE
   key exchanges are performed as defined in [RFC5246].

3.2.  Cipher

   The ARIA_128_CBC cipher suites use ARIA [RFC5794] in CBC mode with a
   128-bit key and 128-bit Initialization Vector (IV); the ARIA_256_CBC
   cipher suites use a 256-bit key and 128-bit IV.

   AES-authenticated encryption with additional data algorithms,
   AEAD_AES_128_GCM, and AEAD_AES_256_GCM are described in [RFC5116].
   AES GCM cipher suites for TLS are described in [RFC5288].  AES and
   ARIA share common characteristics, including key sizes and block
   length.  ARIA_128_GCM and ARIA_256_GCM are defined according to those
   characteristics of AES.

3.3.  PRFs

   The pseudorandom functions (PRFs) SHALL be as follows:

   a.  For cipher suites ending with _SHA256, the PRF is the TLS PRF
       [RFC5246] using SHA-256 as the hash function.

   b.  For cipher suites ending with _SHA384, the PRF is the TLS PRF
       [RFC5246] using SHA-384 as the hash function.

3.4.  PSK Cipher Suites

   Pre-shared key cipher suites for TLS are described in [RFC4279],
   [RFC4785], [RFC5487], and [RFC5489].

4.  Security Considerations

   At the time of writing this document, no security problems have been
   found on ARIA (see [YWL]).

   The security considerations in the following RFCs apply to this
   document as well: [RFC4279] [RFC4785] [RFC5116] [RFC5288] [RFC5289]
   [RFC5487] and [GCM].

5.  IANA Considerations

   IANA has allocated the following numbers in the TLS Cipher Suite
   Registry:

   CipherSuite TLS_RSA_WITH_ARIA_128_CBC_SHA256         = { 0xC0,0x3C };
   CipherSuite TLS_RSA_WITH_ARIA_256_CBC_SHA384         = { 0xC0,0x3D };
   CipherSuite TLS_DH_DSS_WITH_ARIA_128_CBC_SHA256      = { 0xC0,0x3E };
   CipherSuite TLS_DH_DSS_WITH_ARIA_256_CBC_SHA384      = { 0xC0,0x3F };
   CipherSuite TLS_DH_RSA_WITH_ARIA_128_CBC_SHA256      = { 0xC0,0x40 };
   CipherSuite TLS_DH_RSA_WITH_ARIA_256_CBC_SHA384      = { 0xC0,0x41 };
   CipherSuite TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x42 };
   CipherSuite TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x43 };
   CipherSuite TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x44 };
   CipherSuite TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x45 };
   CipherSuite TLS_DH_anon_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x46 };
   CipherSuite TLS_DH_anon_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x47 };

   CipherSuite TLS_ECDHE_ECDSA_WITH_ARIA_128_CBC_SHA256 = { 0xC0,0x48 };
   CipherSuite TLS_ECDHE_ECDSA_WITH_ARIA_256_CBC_SHA384 = { 0xC0,0x49 };
   CipherSuite TLS_ECDH_ECDSA_WITH_ARIA_128_CBC_SHA256  = { 0xC0,0x4A };
   CipherSuite TLS_ECDH_ECDSA_WITH_ARIA_256_CBC_SHA384  = { 0xC0,0x4B };
   CipherSuite TLS_ECDHE_RSA_WITH_ARIA_128_CBC_SHA256   = { 0xC0,0x4C };
   CipherSuite TLS_ECDHE_RSA_WITH_ARIA_256_CBC_SHA384   = { 0xC0,0x4D };
   CipherSuite TLS_ECDH_RSA_WITH_ARIA_128_CBC_SHA256    = { 0xC0,0x4E };
   CipherSuite TLS_ECDH_RSA_WITH_ARIA_256_CBC_SHA384    = { 0xC0,0x4F };

   CipherSuite TLS_RSA_WITH_ARIA_128_GCM_SHA256         = { 0xC0,0x50 };
   CipherSuite TLS_RSA_WITH_ARIA_256_GCM_SHA384         = { 0xC0,0x51 };
   CipherSuite TLS_DHE_RSA_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x52 };
   CipherSuite TLS_DHE_RSA_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x53 };
   CipherSuite TLS_DH_RSA_WITH_ARIA_128_GCM_SHA256      = { 0xC0,0x54 };
   CipherSuite TLS_DH_RSA_WITH_ARIA_256_GCM_SHA384      = { 0xC0,0x55 };
   CipherSuite TLS_DHE_DSS_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x56 };
   CipherSuite TLS_DHE_DSS_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x57 };
   CipherSuite TLS_DH_DSS_WITH_ARIA_128_GCM_SHA256      = { 0xC0,0x58 };
   CipherSuite TLS_DH_DSS_WITH_ARIA_256_GCM_SHA384      = { 0xC0,0x59 };
   CipherSuite TLS_DH_anon_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x5A };
   CipherSuite TLS_DH_anon_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x5B };

   CipherSuite TLS_ECDHE_ECDSA_WITH_ARIA_128_GCM_SHA256 = { 0xC0,0x5C };
   CipherSuite TLS_ECDHE_ECDSA_WITH_ARIA_256_GCM_SHA384 = { 0xC0,0x5D };
   CipherSuite TLS_ECDH_ECDSA_WITH_ARIA_128_GCM_SHA256  = { 0xC0,0x5E };
   CipherSuite TLS_ECDH_ECDSA_WITH_ARIA_256_GCM_SHA384  = { 0xC0,0x5F };
   CipherSuite TLS_ECDHE_RSA_WITH_ARIA_128_GCM_SHA256   = { 0xC0,0x60 };
   CipherSuite TLS_ECDHE_RSA_WITH_ARIA_256_GCM_SHA384   = { 0xC0,0x61 };
   CipherSuite TLS_ECDH_RSA_WITH_ARIA_128_GCM_SHA256    = { 0xC0,0x62 };
   CipherSuite TLS_ECDH_RSA_WITH_ARIA_256_GCM_SHA384    = { 0xC0,0x63 };

   CipherSuite TLS_PSK_WITH_ARIA_128_CBC_SHA256         = { 0xC0,0x64 };
   CipherSuite TLS_PSK_WITH_ARIA_256_CBC_SHA384         = { 0xC0,0x65 };
   CipherSuite TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x66 };
   CipherSuite TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x67 };
   CipherSuite TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256     = { 0xC0,0x68 };
   CipherSuite TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384     = { 0xC0,0x69 };
   CipherSuite TLS_PSK_WITH_ARIA_128_GCM_SHA256         = { 0xC0,0x6A };
   CipherSuite TLS_PSK_WITH_ARIA_256_GCM_SHA384         = { 0xC0,0x6B };
   CipherSuite TLS_DHE_PSK_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x6C };
   CipherSuite TLS_DHE_PSK_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x6D };
   CipherSuite TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256     = { 0xC0,0x6E };
   CipherSuite TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384     = { 0xC0,0x6F };
   CipherSuite TLS_ECDHE_PSK_WITH_ARIA_128_CBC_SHA256   = { 0xC0,0x70 };
   CipherSuite TLS_ECDHE_PSK_WITH_ARIA_256_CBC_SHA384   = { 0xC0,0x71 };

6.  References

6.1.  Normative References

   [GCM]       Dworkin, M., "Recommendation for Block Cipher Modes of
               Operation: Galois/Counter Mode (GCM) and GMAC", NIST
               SP 800-38D, November 2007.

   [RFC2119]   Bradner, S., "Key words for use in RFCs to Indicate
               Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4279]   Eronen, P. and H. Tschofenig, "Pre-Shared Key
               Ciphersuites for Transport Layer Security (TLS)",
               RFC 4279, December 2005.

   [RFC4785]   Blumenthal, U. and P. Goel, "Pre-Shared Key (PSK)
               Ciphersuites with NULL Encryption for Transport Layer
               Security (TLS)", RFC 4785, January 2007.

   [RFC5116]   McGrew, D., "An Interface and Algorithms for
               Authenticated Encryption", RFC 5116, January 2008.

   [RFC5246]   Dierks, T. and E. Rescorla, "The Transport Layer Security
               (TLS) Protocol Version 1.2", RFC 5246, August 2008.

   [RFC5288]   Salowey, J., Choudhury, A., and D. McGrew, "AES Galois
               Counter Mode (GCM) Cipher Suites for TLS", RFC 5288,
               August 2008.

   [RFC5289]   Rescorla, E., "TLS Elliptic Curve Cipher Suites with SHA-
               256/384 and AES Galois Counter Mode (GCM)", RFC 5289,
               August 2008.

   [RFC5487]   Badra, M., "Pre-Shared Key Cipher Suites for TLS with
               SHA-256/384 and AES Galois Counter Mode", RFC 5487,
               March 2009.

   [RFC5489]   Badra, M. and I. Hajjeh, "ECDHE_PSK Cipher Suites for
               Transport Layer Security (TLS)", RFC 5489, March 2009.

   [RFC5794]   Lee, J., Lee, J., Kim, J., Kwon, D., and C. Kim, "A
               Description of the ARIA Encryption Algorithm", RFC 5794,
               March 2010.

6.2.  Informative References

   [ARIAKS]    Korean Agency for Technology and Standards, "128 bit
               block encryption algorithm ARIA - Part 1: General (in
               Korean)", KS X 1213-1:2009, December 2009.

   [ARIAPKCS]  RSA Laboratories, "Additional PKCS #11 Mechanisms",
               PKCS #11 v2.20 Amendment 3 Revision 1, January 2007.

   [Wang05]    Wang, X., Yin, Y., and H. Yu, "Finding Collisions in the
               Full SHA-1", CRYPTO 2005, LNCS vol.3621, pp.17-36,
               August 2005.

   [YWL]       Li, Y., Wu, W., and L. Zhang, "Integral attacks on
               reduced-round ARIA block cipher", ISPEC 2010,
               LNCS Vol.6047, pp. 19-29, May 2010.

Authors' Addresses

   Woo-Hwan Kim
   National Security Research Institute
   P.O.Box 1, Yuseong
   Daejeon  305-350
   Korea

   EMail: whkim5@ensec.re.kr


   Jungkeun Lee
   National Security Research Institute
   P.O.Box 1, Yuseong
   Daejeon  305-350
   Korea

   EMail: jklee@ensec.re.kr


   Je-Hong Park
   National Security Research Institute
   P.O.Box 1, Yuseong
   Daejeon  305-350
   Korea

   EMail: jhpark@ensec.re.kr


   Daesung Kwon
   National Security Research Institute
   P.O.Box 1, Yuseong
   Daejeon  305-350
   Korea

   EMail: ds_kwon@ensec.re.kr