Alternative Approach for Mixing Preshared Keys in IKEv2 for Post-quantum Security
draft-smyslov-ipsecme-ikev2-qr-alt-02

Document Type Active Internet-Draft (individual)
Last updated 2020-08-03
Stream (None)
Intended RFC status (None)
Formats plain text pdf htmlized (tools) htmlized bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date
Responsible AD (None)
Send notices to (None)
Network Working Group                                         V. Smyslov
Internet-Draft                                                ELVIS-PLUS
Intended status: Standards Track                          August 3, 2020
Expires: February 4, 2021

Alternative Approach for Mixing Preshared Keys in IKEv2 for Post-quantum
                                Security
                 draft-smyslov-ipsecme-ikev2-qr-alt-02

Abstract

   An IKEv2 extension defined in [RFC8784] allows IPsec traffic to be
   protected against someone storing VPN communications today and
   decrypting it later, when (and if) quantum computers are available.
   However, this protection doesn't cover an initial IKEv2 SA, which
   might be unacceptable in some scenarios.  This specification defines
   an alternative way get the same protection against quantum computers,
   which allows to extend it on the initial IKEv2 SA.

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 February 4, 2021.

Copyright Notice

   Copyright (c) 2020 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

Smyslov                 Expires February 4, 2021                [Page 1]
Internet-Draft          Alternative PPK for IKEv2            August 2020

   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.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology and Notation  . . . . . . . . . . . . . . . . . .   3
   3.  Alternative Approach Description  . . . . . . . . . . . . . .   3
   4.  Computing IKE SA Keys . . . . . . . . . . . . . . . . . . . .   5
   5.  Comparison of the Conventional and the Alternative Approaches   6
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   6
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   6
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   6
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   7
     9.2.  Informative References  . . . . . . . . . . . . . . . . .   7
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   7

1.  Introduction

   The Internet Key Exchange Protocol version 2, defined in [RFC7296],
   is used in the IPsec architecture to perform authenticated key
   exchange.  [RFC8784] defines an extension of IKEv2 for protecting
   today's VPN traffic against future quantum computers.  At the time
   this extension was being developed, it was a consensus in the IPSECME
   WG that only IPsec traffic needs to have such a protection.  It was
   believed that no sensitive information is transferred over IKE SA and
   extending the protection to also cover IKE SA traffic would require
   serious modifications to core IKEv2 protocol, that contradicted to
   one of the goals to minimize such changes.  For the cases when this
   protection is needed it was suggested to immediately rekey IKE SA
   once it is created.

   In some situations it is desirable to have this protection for IKE SA
   from the very beginning, when an initial IKE SA is created.  An
   example of such situation is Group Key Management protocol using
   IKEv2, defined in [I-D.ietf-ipsecme-g-ikev2].  In this protocol
   session keys are transferred from Group Controller / Key Server
   (GCKS) to Group Members (GM) immediately once an initial IKE SA is
   created.  While it is possible to postpone transfer of the keys until
   the IKE SA is rekeyed (and [I-D.ietf-ipsecme-g-ikev2] specifies how
   to do it), the needed sequence of actions introduces an additional
   delay and adds unnecessary complexity to the protocol.

   Since [RFC8784] was written, a new IKE_INTERMEDIATE exchange for
Show full document text