--- 1/draft-ietf-lamps-ocsp-nonce-01.txt 2020-05-15 01:13:25.650482243 -0700 +++ 2/draft-ietf-lamps-ocsp-nonce-02.txt 2020-05-15 01:13:25.666482649 -0700 @@ -1,18 +1,19 @@ LAMPS M. Sahni, Ed. Internet-Draft Palo Alto Networks -Intended status: Standards Track April 26, 2020 -Expires: October 28, 2020 +Updates: 6960 (if approved) May 15, 2020 +Intended status: Standards Track +Expires: November 16, 2020 OCSP Nonce Extension - draft-ietf-lamps-ocsp-nonce-01 + draft-ietf-lamps-ocsp-nonce-02 Abstract This document specifies the updated format of the Nonce extension in Online Certificate Status Protocol (OCSP) request and response messages. OCSP is used to check the status of a certificate and the Nonce extension is used in the OCSP request and response messages to avoid replay attacks. This document updates the RFC 6960 Status of This Memo @@ -23,54 +24,53 @@ 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 October 28, 2020. + This Internet-Draft will expire on November 16, 2020. 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 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 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 2 - 2. OCSP Extensions . . . . . . . . . . . . . . . . . . . . . . . 2 + 2. OCSP Extensions . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Nonce Extension . . . . . . . . . . . . . . . . . . . . . 3 - 3. Security Considerations . . . . . . . . . . . . . . . . . . . 3 + 3. Security Considerations . . . . . . . . . . . . . . . . . . . 4 3.1. Replay Attack . . . . . . . . . . . . . . . . . . . . . . 4 3.2. Nonce Collision . . . . . . . . . . . . . . . . . . . . . 4 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 5. Changes to Appendix B. of RFC 6960 . . . . . . . . . . . . . 4 5.1. Changes to Appendix B.1. OCSP in ASN.1 - 1998 Syntax . . 4 5.2. Changes to Appendix B.2 OCSP in ASN.1 - 2008 Syntax . . . 5 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 6.1. Normative References . . . . . . . . . . . . . . . . . . 5 6.2. Informative References . . . . . . . . . . . . . . . . . 5 - 6.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction This document updates the usage and format of the Nonce extension used in OCSP request and response messages. This extension was previously defined in section 4.1.1 of [RFC6960]. The [RFC6960] does not mention any minimum and maximum length of the nonce extension. Due to not having an upper or lower limit of the length of the Nonce extension, the OCSP responders that follow [RFC6960] may be @@ -106,22 +106,22 @@ * Service Locator * Preferred Signature Algorithms * Extended Response Definition This document only specifies the new format for Nonce extension and does not change the specification of any of the other standard extensions. 2.1. Nonce Extension - This section updates the Section 4.4.1 [1] of [RFC6960] which - describes the OCSP Nonce extension. + This section updates the Section 4.4.1 of [RFC6960] which describes + the OCSP Nonce extension. The nonce cryptographically binds a request and a response to prevent replay attacks. The nonce is included as one of the requestExtensions in requests, while in responses it would be included as one of the responseExtensions. In both the request and the response, the nonce will be identified by the object identifier id-pkix-ocsp-nonce, while the extnValue is the value of the nonce. If Nonce extension is present then the length of nonce MUST be at least 1 octet and can be up to 32 octets. @@ -163,22 +163,21 @@ an attacker may prefetch responses with the predicted nonce and can replay them, thus defeating the purpose of using nonce. Therefore the client MUST use a nonce value that contains cryptographically strong randomness and is freshly generated. Also if the length of the nonce is very small e.g. 1 octet then an attacker can prefetch responses with all the possible values of the nonce and replay a matching nonce. A client SHOULD use 32 octets for the nonce length. 4. IANA Considerations - This document does not include any new media type registrations - for OCSP. + This document does not call for any IANA actions. 5. Changes to Appendix B. of RFC 6960 This section updates the ASN.1 definitions of the OCSP Nonce extension in the Appendix B.1 and Appendix B.2 of the [RFC6960] The Appendix B.1 defines OCSP using ASN.1 - 1998 Syntax and Appendix B.2 defines OCSP using ASN.1 - 2008 Syntax 5.1. Changes to Appendix B.1. OCSP in ASN.1 - 1998 Syntax @@ -233,23 +232,19 @@ [RFC4732] Handley, M., Ed., Rescorla, E., Ed., and IAB, "Internet Denial-of-Service Considerations", RFC 4732, DOI 10.17487/RFC4732, December 2006, . [RFC5019] Deacon, A. and R. Hurst, "The Lightweight Online Certificate Status Protocol (OCSP) Profile for High-Volume Environments", RFC 5019, DOI 10.17487/RFC5019, September 2007, . -6.3. URIs - - [1] https://tools.ietf.org/html/rfc6960#section-4.4.1 - Author's Address Mohit Sahni (editor) Palo Alto Networks 3000 Tannery Way Santa Clara, CA 95054 US Email: msahni@paloaltonetworks.com