SCRAM-SHA-256 and SCRAM-SHA-256-PLUS SASL Mechanisms

This document registers the SASL mechanisms SCRAM-SHA-256 and SCRAM-SHA-256-PLUS. The registration form for the SCRAM is also updated. Note: this paragraph may be removed before publication. This document was written because requires that new SASL mechanisms in the SCRAM family be subject to IETF review. This document is being discussed on the kitten@ietf.org mailing list.

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 , except that the hash function for HMAC() and H() uses SHA-256 instead of SHA-1 . For the SCRAM-SHA-256/SCRAM-SHA-256-PLUS SASL mechanisms, servers SHOULD announce a hash iteration-count of at least 4096. !!!!!!!!!!!!!!!! Note that the appropriate value to specify here is being actively discussed. !!!!!!!!!!!!!!!! The GSS-API mechanism OID for SCRAM-SHA-256 is [to be assigned by IANA] (see ). 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): n,,n=user,r=rOprNGfwEbeRWgbNEkqO r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0, s=W22ZaJ0SNY7soEsUEjb6gQ==,i=4096 c=biws,r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0, p=dHzbZapWIk4jUhN+Ute9ytag9zjfMHgsqmmiz7AndVQ= v=6rriTRBi23WpRR/wtup+mMhUZUn/dB5nLTJRsjl95G4=

The IANA registry for the SCRAM family of SASL mechanisms is updated as follows: 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 Published specification (optional, recommended): 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" 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 . IANA has added the following entries to the SASL Mechanism registry established by : 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 7 of Published specification (optional, recommended): 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 7 of Published specification (optional, recommended): 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: IANA needs to assign a GSS-API mechanism OID for SCRAM-SHA-256 from the iso.org.dod.internet.security.mechanisms prefix (see the "SMI Security for Mechanism Codes" registry).

This document benefited from discussions on the KITTEN WG mailing list. The author would like to specially thank ...