[Docs] [txt|pdf|xml|html] [Tracker] [Email] [Diff1] [Diff2] [Nits]

Versions: 00 01 02 03 draft-ietf-dime-local-keytran

Network Working Group                                         Q. Wu, Ed.
Internet-Draft                                                    Huawei
Intended status: Standards Track                            G. Zorn, Ed.
Expires: June 7, 2010                                        Network Zen
                                                        December 4, 2009


     Diameter Attribute-Value Pairs for Cryptographic Key Transport
                     draft-wu-dime-local-keytran-03

Abstract

   Some Authentication, Authorization, and Accounting (AAA) applications
   require the transport of cryptographic keying material; this document
   specifies a set of Attribute-Value Pairs (AVPs) providing native
   Diameter support of cryptographic key delivery.

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
   provisions of BCP 78 and BCP 79.  This document may not be modified,
   and derivative works of it may not be created, except to format it
   for publication as an RFC or to translate it into languages other
   than English.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on June 7, 2010.

Copyright Notice

   Copyright (c) 2009 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




Wu & Zorn                 Expires June 7, 2010                  [Page 1]

Internet-Draft         Diameter Key Transport AVPs         December 2009


   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 BSD License.


Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . 3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3
     2.1.  Standards Language  . . . . . . . . . . . . . . . . . . . . 3
     2.2.  Technical Terms and Acronyms  . . . . . . . . . . . . . . . 3
   3.  Attribute-Value Pair Definitions  . . . . . . . . . . . . . . . 4
     3.1.  Key AVP . . . . . . . . . . . . . . . . . . . . . . . . . . 4
       3.1.1.  Key-Type AVP  . . . . . . . . . . . . . . . . . . . . . 4
       3.1.2.  Key-Name AVP  . . . . . . . . . . . . . . . . . . . . . 5
       3.1.3.  Keying-Material AVP . . . . . . . . . . . . . . . . . . 5
       3.1.4.  Key-Lifetime AVP  . . . . . . . . . . . . . . . . . . . 5
   4.  AVP Occurrence Table  . . . . . . . . . . . . . . . . . . . . . 6
   5.  Security Considerations . . . . . . . . . . . . . . . . . . . . 6
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6
     6.1.  AVP Codes . . . . . . . . . . . . . . . . . . . . . . . . . 6
     6.2.  AVP Values  . . . . . . . . . . . . . . . . . . . . . . . . 6
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . 7
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . . . 7
     8.1.  Normative References  . . . . . . . . . . . . . . . . . . . 7
     8.2.  Informative References  . . . . . . . . . . . . . . . . . . 7
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . . 8


















Wu & Zorn                 Expires June 7, 2010                  [Page 2]

Internet-Draft         Diameter Key Transport AVPs         December 2009


1.  Introduction

   The Diameter EAP application [RFC4072] defines the EAP-Master-
   Session-Key and EAP-Key-Name AVPs for the purpose of transporting
   cryptographic keying material derived during the execution of certain
   EAP [RFC3748] methods (for example, EAP-TLS [RFC5216]).  At most one
   instance of either of these AVPs is allowed in any Diameter message.

   However, recent work [RFC5295] has specified methods to derive other
   keys from the keying material created during EAP method execution
   that may require transport in addition to the MSK.  In addition, ERP
   [RFC5296] specifies new keys that may need to be transported between
   Diameter nodes.

   This note specifies a set of AVPs allowing the transport of multiple
   cryptographic keys in a single Diameter message.


2.  Terminology

2.1.  Standards Language

   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 RFC 2119 [RFC2119].

2.2.  Technical Terms and Acronyms

   DER
      Diameter EAP request [RFC4072].

   DEA
      Diameter EAP Answer [RFC4072].

   DSRK
      Domain-Specific Root Key [RFC5295].

   DSUSRK  Domain-Specific Usage-Specific Root Key. This is a Usage-
      Specific Root Key derived from a DSRK [RFC5295].

   EAP
      Extensible Authentication Protocol [RFC3748].

   EMSK
      Extended Master Session Key [RFC3748].






Wu & Zorn                 Expires June 7, 2010                  [Page 3]

Internet-Draft         Diameter Key Transport AVPs         December 2009


   ERP
      EAP Re-authentication Protocol [RFC5296].

   MSK
      Master Session Key [RFC3748].

   rMSK
      reauthentication MSK [RFC5296].  This is a per-authenticator key,
      derived from the rRK (see below).

   rRK
      reauthentication Root Key, derived from the EMSK or DSRK
      [RFC5296].

   USRK
      Usage-Specific Root Key [RFC5295]


3.  Attribute-Value Pair Definitions

   This section defines new AVPs for the transport of cryptographic keys
   in the Diameter EAP application [RFC4072], as well as other Diameter
   applications.

3.1.  Key AVP

   The Key AVP (AVP Code <AC1>) is of type Grouped [RFC3588] It contains
   the name, type and optionally, the usable lifetime of the key, as
   well as the keying material itself.

   Key ::= < AVP Header: AC1 >
             { Key-Type }
             { Keying-Material }
             [ Key-Lifetime ]
             [ Key-Name ]
           * [ AVP ]

3.1.1.  Key-Type AVP

   The Key-Type AVP (AVP Code <AC2>) is of type Enumerated and signifies
   the type of the key being sent.  The Key-Type AVP MAY be included in
   a DER command as a signal that a certain type of key is required in
   the response (e.g., to support ERP).  The following values are
   defined in this document:







Wu & Zorn                 Expires June 7, 2010                  [Page 4]

Internet-Draft         Diameter Key Transport AVPs         December 2009


   MSK (0)
      The EAP Master Session Key [RFC3748]

   DSRK (1)
      A Domain-Specific Root Key [RFC5295].

   USRK (2)
      A Usage Specific Root Key [RFC5295].

   rRK (3)
      A reauthentication Root Key [RFC5296].

   rMSK (4)
      A reauthentication Master Session Key [RFC5296].

   DSUSRK (5)  A Domain-Specific Usage-Specific Root Key [RFC5295].

   If additional values are needed, they are to be assigned by IANA
   according to the policy stated in Section 6.2

3.1.2.  Key-Name AVP

   The Key-Name AVP is of type OctetString.  It contains an opaque key
   identifier.  Exactly how this name is generated and used depends on
   the key type and link layer in question, and is beyond the scope of
   this document (see [RFC5247] and [RFC5295] for discussions of key
   name generation in the context of EAP).

3.1.3.  Keying-Material AVP

   The Keying-Material AVP (AVP Code <AC3>) is of type OctetString.  The
   exact usage of this keying material depends upon several factors,
   including the link layer in use and the type of the key; it is beyond
   the scope of this document.

3.1.4.  Key-Lifetime AVP

   The Key-Lifetime AVP (AVP Code <AC4>) is of type Integer64 [RFC3588]
   and represents the period of time (in seconds) for which the contents
   of the Keying-Material AVP Section 3.1.3 is valid.

   NOTE:
      Applications using this value SHOULD consider the beginning of the
      lifetime to be the point in time when the keying material is first
      used.






Wu & Zorn                 Expires June 7, 2010                  [Page 5]

Internet-Draft         Diameter Key Transport AVPs         December 2009


4.  AVP Occurrence Table

   The following table lists the AVPs that MAY be present in the DER and
   DEA commands [RFC4072].

                                            +---------------+
                                            |  Command-Code |
                                            +-+-----+-----+-+
               AVP Name                       | DER | DEA |
               -------------------------------|-----+-----+
               Key                            |  0  |  0+ |
               Key-Type                       |  0+ |  0  |
               Key-Name                       | 0-1 | 0-1 |
                                              +-----+-----+

                      DER and DEA Commands AVP Table


5.  Security Considerations

   The security considerations applicable to the Diameter Base Protocol
   [RFC3588] are also applicable to this document.


6.  IANA Considerations

   Upon publication of this memo as an RFC, IANA is requested to assign
   values as described in the following sections.

6.1.  AVP Codes

   Codes must be assigned for the following AVPs using the policy
   specified in RFC 3588, Section 11.1.1:

   o  Key (<AC1>, Section 3.1)

   o  Key-Type (<AC2>, Section 3.1.1)

   o  Keying-Material (<AC3>, Section 3.1.3

   o  Key-Lifetime (<AC4>, Section 3.1.4

6.2.  AVP Values

   New values may be assigned for the Key-Type AVP (Section 3.1.1) using
   the "First Come First Served" policy [RFC5226].





Wu & Zorn                 Expires June 7, 2010                  [Page 6]

Internet-Draft         Diameter Key Transport AVPs         December 2009


7.  Acknowledgements

   Thanks to Semyon Mizikovsky and Sebastien Decugis for useful
   comments.

   Section 3.1.2 is largely derived from Section 4.1.4 of RFC 4072
   [RFC4072].


8.  References

8.1.  Normative References

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

   [RFC3588]  Calhoun, P., Loughney, J., Guttman, E., Zorn, G., and J.
              Arkko, "Diameter Base Protocol", RFC 3588, September 2003.

   [RFC3748]  Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H.
              Levkowetz, "Extensible Authentication Protocol (EAP)",
              RFC 3748, June 2004.

   [RFC4072]  Eronen, P., Hiller, T., and G. Zorn, "Diameter Extensible
              Authentication Protocol (EAP) Application", RFC 4072,
              August 2005.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

8.2.  Informative References

   [RFC5216]  Simon, D., Aboba, B., and R. Hurst, "The EAP-TLS
              Authentication Protocol", RFC 5216, March 2008.

   [RFC5247]  Aboba, B., Simon, D., and P. Eronen, "Extensible
              Authentication Protocol (EAP) Key Management Framework",
              RFC 5247, August 2008.

   [RFC5295]  Salowey, J., Dondeti, L., Narayanan, V., and M. Nakhjiri,
              "Specification for the Derivation of Root Keys from an
              Extended Master Session Key (EMSK)", RFC 5295,
              August 2008.

   [RFC5296]  Narayanan, V. and L. Dondeti, "EAP Extensions for EAP Re-
              authentication Protocol (ERP)", RFC 5296, August 2008.




Wu & Zorn                 Expires June 7, 2010                  [Page 7]

Internet-Draft         Diameter Key Transport AVPs         December 2009


Authors' Addresses

   Qin Wu (editor)
   Huawei Technologies Co., Ltd.
   Site B, Floor 12F, Huihong Mansion, No.91 Baixia Rd.
   Nanjing, JiangSu  210001
   China

   Phone: +86-25-84565892
   Email: Sunseawq@huawei.com


   Glen Zorn (editor)
   Network Zen
   1310 East Thomas Street
   Seattle, Washington  98102
   +1 (206) 377-9035

   Email: gwz@net-zen.net
































Wu & Zorn                 Expires June 7, 2010                  [Page 8]


Html markup produced by rfcmarkup 1.107, available from http://tools.ietf.org/tools/rfcmarkup/