Diffie-Hellman Proof-of-Possession Algorithms
RFC 6955

Internet Engineering Task Force (IETF)                         J. Schaad
Request for Comments: 6955                       Soaring Hawk Consulting
Obsoletes: 2875                                        H. Prafullchandra
Category: Standards Track                                  HyTrust, Inc.
ISSN: 2070-1721                                                 May 2013

             Diffie-Hellman Proof-of-Possession Algorithms

Abstract

   This document describes two methods for producing an integrity check
   value from a Diffie-Hellman key pair and one method for producing an
   integrity check value from an Elliptic Curve key pair.  This behavior
   is needed for such operations as creating the signature of a Public-
   Key Cryptography Standards (PKCS) #10 Certification Request.  These
   algorithms are designed to provide a Proof-of-Possession of the
   private key and not to be a general purpose signing algorithm.

   This document obsoletes RFC 2875.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6955.

Schaad & Prafullchandra      Standards Track                    [Page 1]
RFC 6955                    DH POP Algorithms                   May 2013

Copyright Notice

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Schaad & Prafullchandra      Standards Track                    [Page 2]
RFC 6955                    DH POP Algorithms                   May 2013

Table of Contents

   1. Introduction ....................................................3
      1.1. Changes since RFC 2875 .....................................4
      1.2. Requirements Terminology ...................................5
   2. Terminology .....................................................5
   3. Notation ........................................................5
   4. Static DH Proof-of-Possession Process ...........................6
      4.1. ASN.1 Encoding .............................................8
   5. Discrete Logarithm Signature ...................................11
      5.1. Expanding the Digest Value ................................11
      5.2. Signature Computation Algorithm ...........................12
      5.3. Signature Verification Algorithm ..........................13
      5.4. ASN.1 Encoding ............................................14
   6. Static ECDH Proof-of-Possession Process ........................16
      6.1. ASN.1 Encoding ............................................18
   7. Security Considerations ........................................20
   8. References .....................................................21
      8.1. Normative References ......................................21
      8.2. Informative References ....................................21
   Appendix A. ASN.1 Modules .........................................23
     A.1. 2008 ASN.1 Module ..........................................23
     A.2. 1988 ASN.1 Module ..........................................28