GSS-API Key Exchange with SHA2
draft-ietf-curdle-gss-keyex-sha2-10

Document Type Active Internet-Draft (curdle WG)
Last updated 2019-09-09 (latest revision 2019-07-23)
Replaces draft-ssorce-gss-keyex-sha2
Stream IETF
Intended RFC status Proposed Standard
Formats plain text xml pdf htmlized bibtex
Reviews
Stream WG state Submitted to IESG for Publication
Document shepherd Daniel Migault
Shepherd write-up Show (last changed 2018-02-23)
IESG IESG state RFC Ed Queue
Consensus Boilerplate Yes
Telechat date
Responsible AD Benjamin Kaduk
Send notices to Daniel Migault <daniel.migault@ericsson.com>
IANA IANA review state Version Changed - Review Needed
IANA action state RFC-Ed-Ack
RFC Editor RFC Editor state EDIT
Internet Engineering Task Force                                 S. Sorce
Internet-Draft                                                  H. Kario
Updates: 4462 (if approved)                                Red Hat, Inc.
Intended status: Standards Track                            Jul 22, 2019
Expires: January 23, 2020

                     GSS-API Key Exchange with SHA2
                  draft-ietf-curdle-gss-keyex-sha2-10

Abstract

   This document specifies additions and amendments to RFC4462.  It
   defines a new key exchange method that uses SHA-2 for integrity and
   deprecates weak DH groups.  The purpose of this specification is to
   modernize the cryptographic primitives used by GSS Key Exchanges.

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 https://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 January 23, 2020.

Copyright Notice

   Copyright (c) 2019 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
   (https://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.

Sorce & Kario           Expires January 23, 2020                [Page 1]
Internet-Draft               GSS Keyex SHA2                     Jul 2019

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Rationale . . . . . . . . . . . . . . . . . . . . . . . . . .   2
   3.  Document Conventions  . . . . . . . . . . . . . . . . . . . .   2
   4.  New Diffie-Hellman Key Exchange methods . . . . . . . . . . .   3
   5.  New Elliptic Curve Diffie-Hellman Key Exchange methods  . . .   4
     5.1.  Generic GSS-API Key Exchange with ECDH  . . . . . . . . .   4
     5.2.  ECDH Key Exchange Methods . . . . . . . . . . . . . . . .   8
   6.  Deprecated Algorithms . . . . . . . . . . . . . . . . . . . .   9
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
     8.1.  New Finite Field DH mechanisms  . . . . . . . . . . . . .  10
     8.2.  New Elliptic Curve DH mechanisms  . . . . . . . . . . . .  10
     8.3.  GSSAPI Delegation . . . . . . . . . . . . . . . . . . . .  10
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  11
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   SSH GSS-API Methods [RFC4462] allows the use of GSSAPI [RFC2743] for
   authentication and key exchange in SSH.  It defines three exchange
   methods all based on DH groups and SHA-1.  This document updates
   RFC4462 with new methods intended to support environments that desire
   to use the SHA-2 cryptographic hash functions.

2.  Rationale

   Due to security concerns with SHA-1 [RFC6194] and with MODP groups
   with less than 2048 bits [NIST-SP-800-131Ar1] we propose the use of
   hashes based on SHA-2 [RFC6234] with DH group14, group15, group16,
   group17 and group18 [RFC3526].  Additionally we add support for key
   exchange based on Elliptic Curve Diffie Hellman with the NIST P-256,
   P-384 and P-521 [SEC2v2] as well as the X25519 and X448 [RFC7748]
   curves.  Following the practice of [RFC8268] only SHA-256 and SHA-512
   hashes are used for DH groups.  For NIST curves the same curve-to-
   hashing algorithm pairing used in [RFC5656] is adopted for
   consistency.

3.  Document Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 RFC2119 [RFC2119] RFC8174 [RFC8174] when, and only when, they
   appear in all capitals, as shown here.

Sorce & Kario           Expires January 23, 2020                [Page 2]
Internet-Draft               GSS Keyex SHA2                     Jul 2019
Show full document text