Re-keying Mechanisms for Symmetric Keys
draft-irtf-cfrg-re-keying-08

Document Type Active Internet-Draft (cfrg RG)
Last updated 2017-10-30 (latest revision 2017-10-09)
Replaces draft-cfrg-re-keying
Stream IRTF
Intended RFC status Informational
Formats plain text pdf xml html bibtex
Stream IRTF state Active RG Document
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date
Responsible AD (None)
Send notices to (None)
CFRG                                                  S. Smyshlyaev, Ed.
Internet-Draft                                                 CryptoPro
Intended status: Informational                           October 9, 2017
Expires: April 12, 2018

                Re-keying Mechanisms for Symmetric Keys
                      draft-irtf-cfrg-re-keying-08

Abstract

   A certain maximum amount of data can be safely encrypted when
   encryption is performed under a single key.  This amount is called
   "key lifetime".  This specification describes a variety of methods to
   increase the lifetime of symmetric keys.  It provides external and
   internal re-keying mechanisms based on hash functions and on block
   ciphers, that can be used with modes of operations such as CTR, GCM,
   CBC, CFB and OMAC.

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 April 12, 2018.

Copyright Notice

   Copyright (c) 2017 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

Smyshlyaev               Expires April 12, 2018                 [Page 1]
Internet-Draft   Re-keying Mechanisms for Symmetric Keys    October 2017

   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions Used in This Document . . . . . . . . . . . . . .   5
   3.  Basic Terms and Definitions . . . . . . . . . . . . . . . . .   5
   4.  Choosing Constructions and Security Parameters  . . . . . . .   6
   5.  External Re-keying Mechanisms . . . . . . . . . . . . . . . .   9
     5.1.  Methods of Key Lifetime Control . . . . . . . . . . . . .  12
     5.2.  Parallel Constructions  . . . . . . . . . . . . . . . . .  12
       5.2.1.  Parallel Construction Based on a KDF on a Block
               Cipher  . . . . . . . . . . . . . . . . . . . . . . .  13
       5.2.2.  Parallel Construction Based on HKDF . . . . . . . . .  13
       5.2.3.  Tree-based Construction . . . . . . . . . . . . . . .  14
     5.3.  Serial Constructions  . . . . . . . . . . . . . . . . . .  15
       5.3.1.  Serial Construction Based on a KDF on a Block Cipher   16
       5.3.2.  Serial Construction Based on HKDF . . . . . . . . . .  17
   6.  Internal Re-keying Mechanisms . . . . . . . . . . . . . . . .  17
     6.1.  Methods of Key Lifetime Control . . . . . . . . . . . . .  20
     6.2.  Constructions that Do Not Require Master Key  . . . . . .  20
       6.2.1.  ACPKM Re-keying Mechanisms  . . . . . . . . . . . . .  20
       6.2.2.  CTR-ACPKM Encryption Mode . . . . . . . . . . . . . .  22
       6.2.3.  GCM-ACPKM Authenticated Encryption Mode . . . . . . .  23
     6.3.  Constructions that Require Master Key . . . . . . . . . .  26
       6.3.1.  ACPKM-Master Key Derivation from the Master Key . . .  26
       6.3.2.  CTR-ACPKM-Master Encryption Mode  . . . . . . . . . .  28
       6.3.3.  GCM-ACPKM-Master Authenticated Encryption Mode  . . .  30
       6.3.4.  CBC-ACPKM-Master Encryption Mode  . . . . . . . . . .  32
       6.3.5.  CFB-ACPKM-Master Encryption Mode  . . . . . . . . . .  35
       6.3.6.  OMAC-ACPKM-Master Authentication Mode . . . . . . . .  37
   7.  Joint Usage of External and Internal Re-keying  . . . . . . .  38
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  38
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  39
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  39
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  40
   Appendix A.  Test examples  . . . . . . . . . . . . . . . . . . .  41
   Appendix B.  Contributors . . . . . . . . . . . . . . . . . . . .  49
   Appendix C.  Acknowledgments  . . . . . . . . . . . . . . . . . .  49
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  49
Show full document text