Storing validation parameters in PKCS#8

Document Type Active Internet-Draft (individual)
Last updated 2018-03-30 (latest revision 2018-03-29)
Stream ISE
Intended RFC status Informational
Formats plain text xml pdf html bibtex
IETF conflict review conflict-review-mavrogiannopoulos-pkcs8-validated-parameters
Stream ISE state In IESG Review
Consensus Boilerplate Unknown
Document shepherd Adrian Farrel
Shepherd write-up Show (last changed 2018-03-29)
IESG IESG state I-D Exists
Telechat date
Responsible AD (None)
Send notices to Adrian Farrel <>
IANA IANA review state IANA OK - No Actions Needed
IANA action state None
Network Working Group                               N. Mavrogiannopoulos
Internet-Draft                                                   Red Hat
Intended status: Informational                            March 29, 2018
Expires: September 30, 2018

                Storing validation parameters in PKCS#8


   This memo describes a method of storing parameters needed for private
   key validation in the Private-Key Information Syntax Specification as
   defined in RFC5208 (PKCS#8) format.  It is equally applicable the
   alternative implementation of the Private-Key Information Syntax
   Specification as defined in RFC 5958.

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

   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 September 30, 2018.

Copyright Notice

   Copyright (c) 2018 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
   ( 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.

Mavrogiannopoulos      Expires September 30, 2018               [Page 1]
Internet-Draft   Storing validation parameters in PKCS#8      March 2018

1.  Introduction

   RSA or DSA private keys generated using the Shawe-Taylor prime
   generation algorithm describled in [FIPS186-4] allow for parameter
   validation, i.e., verify whether the primes are actually prime, and
   were correctly generated.  That is done by generating the parameters
   from a known seed and a selected hash algorithm.

   Storing these parameters in a private key format such as the RSA
   Private Key Syntax from PKCS#1 [RFC8017], or common representations
   for DSA private keys, does not allow attaching information on the
   parameters needed for validation.  The purpose of the document is to
   describe such a method using the Private-Key Information Syntax
   Specification as defined in [RFC5208], as well as on the alternative
   specification on [RFC5958].

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "OPTIONAL" in this document are to be interpreted as described in
   BCP14 [RFC2119][RFC8174] when, and only when, they appear in all
   capitals, as shown here.

3.  ValidationParams attribute

   The information related to the validation parameters is stored as an
   attribute in the PrivateKeyInfo structure.  The attribute is
   identified by the id-attr-validation-parameters object identifier and
   contains as AttributeValue a single ValidationParams structure.

     id-attr-validation-parameters OBJECT IDENTIFIER ::=
                                              {1 3 6 1 4 1 2312 18 8 1}

     ValidationParams ::= SEQUENCE {
         hashAlgo OBJECT IDENTIFIER,
         seed OCTET STRING

   The algorithm identifier in the ValidationParams should be a hash
   algorithm identifier for the [FIPS186-4] methods.  The
   ValidationParams sequence must be DER encoded [CCITT.X690.2002].

4.  Example Structure

   The following structure contains an RSA key generated using the
   [FIPS186-4] section B.3.3 algorithm with SHA2-384 hash.  The seed
   used is

Mavrogiannopoulos      Expires September 30, 2018               [Page 2]
Internet-Draft   Storing validation parameters in PKCS#8      March 2018

   (hex encoded).

   -----BEGIN PRIVATE KEY-----
Show full document text