Kitten T. Hansen Internet-Draft AT&T Laboratories Updates: 5802 (if approved) October 27, 2014 Intended status: Informational Expires: April 30, 2015 SCRAM-SHA-256 and SCRAM-SHA-256-PLUS SASL Mechanisms draft-hansen-scram-sha256-02 Abstract This document registers the SASL mechanisms SCRAM-SHA-256 and SCRAM- SHA-256-PLUS. It also updates RFC 5802 in minor ways. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on April 30, 2015. Copyright Notice Copyright (c) 2014 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. Hansen Expires April 30, 2015 [Page 1]
Internet-Draft SASL SCRAM-SHA-256/SCRAM-SHA-256-PLUS October 2014 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. SCRAM-SHA-256 and SCRAM-SHA-256-PLUS . . . . . . . . . . . . 2 3. Security Considerations . . . . . . . . . . . . . . . . . . . 3 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 6.1. Normative References . . . . . . . . . . . . . . . . . . 5 6.2. Informative References . . . . . . . . . . . . . . . . . 5 6.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction This document registers the SASL mechanisms SCRAM-SHA-256 and SCRAM- SHA-256-PLUS. The registration form for the SCRAM family of algorithms is also updated. Note: this paragraph may be removed before publication. This document was written because [RFC5802] requires that new SASL mechanisms in the SCRAM family be subject to IETF review. This document is being discussed in the KITTEN working group (see the kitten@ietf.org [1] mailing list). It was pursued further because of a desire for its use within a document being discussed in the HTTP- AUTH working group (see the httpauth@ietf.org [2] mailing list). 2. SCRAM-SHA-256 and SCRAM-SHA-256-PLUS The SCRAM-SHA-256 and SCRAM-SHA-256-PLUS SASL mechanism are defined in the same way that SCRAM-SHA-1 and SCRAM-SHA-1-PLUS are defined in [RFC5802], except that the hash function for HMAC() and H() uses SHA-256 instead of SHA-1 [RFC6234]. For the SCRAM-SHA-256/SCRAM-SHA-256-PLUS SASL mechanisms, servers SHOULD announce a hash iteration-count of at least 4096. The GSS-API mechanism OID for SCRAM-SHA-256 is TBD1 (see Section 4). This is a simple example of a SCRAM-SHA-256 authentication exchange when the client doesn't support channel bindings (username 'user' and password 'pencil' are used): C: n,,n=user,r=rOprNGfwEbeRWgbNEkqO S: r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0, Hansen Expires April 30, 2015 [Page 2]
Internet-Draft SASL SCRAM-SHA-256/SCRAM-SHA-256-PLUS October 2014 s=W22ZaJ0SNY7soEsUEjb6gQ==,i=4096 C: c=biws,r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0, p=dHzbZapWIk4jUhN+Ute9ytag9zjfMHgsqmmiz7AndVQ= S: v=6rriTRBi23WpRR/wtup+mMhUZUn/dB5nLTJRsjl95G4= 3. Security Considerations The security considerations from [RFC5802] still apply. 4. IANA Considerations The IANA registry for the SCRAM family of SASL mechanisms is updated as follows. This revised form adds two new fields: Minimum iteration-count and Associated OID. In addition, the email address for reviews has been updated. To: iana@iana.org Subject: Registration of a new SASL family SCRAM SASL mechanism name (or prefix for the family): SCRAM-* Security considerations: Section 7 of [RFC5802] Published specification (optional, recommended): RFCXXXX Minimum iteration-count: The minimum iteration-count that servers SHOULD announce Associated OID: IANA SHOULD assign a GSS-API mechanism OID for this mechanism from the iso.org.dod.internet.security.mechanisms prefix (see the "SMI Security for Mechanism Codes" registry). Only one OID needs to be assigned for a SCRAM-* and SCRAM-*-PLUS pair. The same OID should be assigned to both entries in the registry. Person & email address to contact for further information: IETF KITTEN WG kitten@ietf.org Intended usage: COMMON Owner/Change controller: IESG iesg@ietf.org Note: Members of this family MUST be explicitly registered using the "IETF Review" [RFC5226] registration procedure. Reviews MUST be requested on the KITTEN mailing list kitten@ietf.org (or a successor designated by the responsible Security AD). Note to future SCRAM-mechanism designers: each new SCRAM-SASL mechanism MUST be explicitly registered with IANA and MUST comply with SCRAM-mechanism naming convention defined in Section 4 of [RFC5802]. The following values are to be added to the existing registries for SASL SCRAM-SHA-1 and SCRAM-SHA-1-PLUS: Hansen Expires April 30, 2015 [Page 3]
Internet-Draft SASL SCRAM-SHA-256/SCRAM-SHA-256-PLUS October 2014 Minimum iteration-count: 4096 OID: 1.3.6.1.5.5.14 (from [RFC5802]) The following new SASL SCRAM mechanisms are added: IANA has added the following entries to the SASL Mechanism registry established by [RFC4422]: To: iana@iana.org Subject: Registration of a new SASL mechanism SCRAM-SHA-256 SASL mechanism name (or prefix for the family): SCRAM-SHA-256 Security considerations: Section Section 3 of RFCXXXX Published specification (optional, recommended): RFCXXXX Minimum iteration-count: 4096 OID: TBD1 Person & email address to contact for further information: IETF KITTEN WG kitten@ietf.org Intended usage: COMMON Owner/Change controller: IESG iesg@ietf.org Note: To: iana@iana.org Subject: Registration of a new SASL mechanism SCRAM-SHA-256-PLUS SASL mechanism name (or prefix for the family): SCRAM-SHA-256-PLUS Security considerations: Section Section 3 of RFCXXXX Published specification (optional, recommended): RFCXXXX Minimum iteration-count: 4096 OID: TBD1 Person & email address to contact for further information: IETF KITTEN WG kitten@ietf.org Intended usage: COMMON Owner/Change controller: IESG iesg@ietf.org Note: [This note may be removed on publication.] IANA needs to assign the GSS-API mechanism OID TBD1 listed above from the iso.org.dod.internet.security.mechanisms prefix (see the "SMI Security for Mechanism Codes" registry). 5. Acknowledgements This document benefited from discussions on the KITTEN WG mailing list. The author would like to specially thank Russ Albery, Dave Cridland, Shawn Emery, Simon Josefsson, and Alexey Melnikov for their comments on this topic. Hansen Expires April 30, 2015 [Page 4]
Internet-Draft SASL SCRAM-SHA-256/SCRAM-SHA-256-PLUS October 2014 6. References 6.1. Normative References [RFC5802] Newman, C., Menon-Sen, A., Melnikov, A., and N. Williams, "Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API Mechanisms", RFC 5802, July 2010. [RFC6234] Eastlake, D. and T. Hansen, "US Secure Hash Algorithms (SHA and SHA-based HMAC and HKDF)", RFC 6234, May 2011. 6.2. Informative References [RFC4422] Melnikov, A. and K. Zeilenga, "Simple Authentication and Security Layer (SASL)", RFC 4422, June 2006. [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008. 6.3. URIs [1] mailto:kitten@ietf.org [2] mailto:httpauth@ietf.org Author's Address Tony Hansen AT&T Laboratories 200 Laurel Ave. South Middletown, NJ 07748 USA Email: tony+scramsha256@maillennium.att.com Hansen Expires April 30, 2015 [Page 5]
