INTERNET-DRAFT                                                 L. Camara
Network Working Group                                      June 13, 2017
Updates: 5280 (if approved)
Intended Status: Standards Track
Expires: December 15, 2017


     Update to RFC5280 to allow SHA-256 hashes in the Authority Key
            Identifier and Subject Key Identifier extensions
                draft-luis140219-curdle-sha256keyident-00

Abstract

  This document updates RFC 5280, the "Internet X.509 Public Key
  Infrastructure Certificate and Certificate Revocation List (CRL)
  Profile", to allow SHA-256 hashes in the Authority Key Identifier
  and Subject Key Identifier extensions.

Status of This Memo

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   This Internet-Draft will expire on December 15, 2017.

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Table of Contents

  1. Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .   2
  2. Updates to RFC 5280 . . . . . . . . . . . . . . . . . . . . . .   2
  3. Security Considerations . . . . . . . . . . . . . . . . . . . .   2

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  4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . .   2
  5. References  . . . . . . . . . . . . . . . . . . . . . . . . . .   2
  5.1. Normative References  . . . . . . . . . . . . . . . . . . . .   2
  5.2. Informative References  . . . . . . . . . . . . . . . . . . .   2

1. Introduction

   This document updates the "Internet X.509 Public Key Infrastructure
   Certificate and Certificate Revocation List (CRL) Profile" [RFC5280].

   After the first SHA-1 collision in 2017-02-23 [SHATTERED], hash
   collisions are expected to get more efficient and affordable. In the
   near future, SHA-1 may not suffice for identification of keys as keys
   with colliding hashes may be generated.

2. Updates to RFC 5280

   In addition to the two methods defined in Section 4.2.1.2 of RFC 5280,
   a third method is defined below that generates the value of the
   keyIdentifier from the public key:

   The keyIdentifier is composed of the 256-bit SHA-256 hash of the value
   of the BIT STRING subjectPublicKey (excluding the tag, length and
   number of unused bits).

3. Security Considerations

   This document adds capabilities for using more secure technology with
   pre-existent standards, and therefore has no security implications.

4. IANA Considerations

   This document has no actions for IANA.

5. References

5.1. Normative References

   [RFC5280]   Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
               Housley, R., and W. Polk, "Internet X.509 Public Key
               Infrastructure Certificate and Certificate Revocation
               List (CRL) Profile", RFC 5280, May 2008.

5.2. Informative References

   [SHATTERED] Stevens, M., Bursztein, E., Karpman, P., Albertini, A.,
               Markov, Y., Petit-Bianco, A., Invernizzi, L., and C.
               Blaisse, "SHAttered", https://shattered.io, 23 February
               2017.



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Author's Address

Luis Camara (@luis140219 on GitHub)

EMail: luis.camara@live.com.pt

















































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