Internet Engineering Task Force (IETF) H. Sharma, Ed.Internet-DraftRequest for Comments: 9654 Netskope Inc Obsoletes: 8954(if approved) 22 MayAugust 2024 Updates: 6960(if approved) Intended status:Category: Standards TrackExpires: 23 November 2024ISSN: 2070-1721 Online Certificate Status Protocol (OCSP) Nonce Extensiondraft-ietf-lamps-ocsp-nonce-update-11Abstract RFC 8954 imposedthesize constraints on the optional Nonce extension for the Online Certificate Status Protocol (OCSP). OCSP is usedfor checkingto check the status of a certificate, and the Nonce extension is used to cryptographically bind an OCSP response message to a particular OCSP request message. Some environments use cryptographic algorithms that generate a Nonce value that is longer than 32 octets. This documentupdates the maximum allowed length of Nonce to 128 octets. This documentalso modifiesNoncethe "Nonce" section of RFC 6960 to clearly define and differentiate the encoding format and valuesdistinctivelyforaneasier implementation and understanding. This document obsoletes RFC8954 and provides8954, which includes updated ASN.1 modules for OCSP, and updates RFC 6960. Status of This Memo ThisInternet-Draftissubmitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documentsan Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF).Note that other groups may also distribute working documents as Internet-Drafts. The listIt represents the consensus ofcurrent Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents validthe IETF community. It has received public review and has been approved fora maximumpublication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841. Information about the current status ofsix monthsthis document, any errata, and how to provide feedback on it may beupdated, replaced, or obsoleted by other documentsobtained atany 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 23 November 2024.https://www.rfc-editor.org/info/rfc9654. Copyright Notice Copyright (c) 2024 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)(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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . 21.1. Requirements Language. . . . . . . . . . . . . . . . . . 22. OCSP Extensions. . . . . . . . . . . . . . . . . . . . . . . 32.1. Nonce Extension. . . . . . . . . . . . . . . . . . . . . 33. Security Considerations. . . . . . . . . . . . . . . . . . . 43.1. Replay Attack. . . . . . . . . . . . . . . . . . . . . . 44. IANA Considerations. . . . . . . . . . . . . . . . . . . . . 5 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 55. References. . . . . . . . . . . . . . . . . . . . . . . . . . . 55.1. Normative References. . . . . . . . . . . . . . . . . . . . . 55.2. Informative References. . . . . . . . . . . . . . . . . . . . 6Appendix A. ASN.1 Modules. . . . . . . . . . . . . . . . . . . 6A.1. OCSP in ASN.1 - 1998 Syntax. . . . . . . . . . . . . . . 6A.2. OCSP in ASN.1 - 2008 Syntax. . . . . . . . . . . . . . . 10Acknowledgements Author's Address. . . . . . . . . . . . . . . . . . . . . . . . 141. Introduction The Nonce extension was previously defined in Section 4.4.1 of [RFC6960]. The Nonce cryptographically binds an OCSP request and a response. It guarantees the freshness of an OCSP response andto avoidavoids replay attacks. This extension was updated in [RFC8954]. [RFC8954] limits the maximum Nonce length to 32 octets. To support cryptographic algorithms that generate a Nonce that is longer than 32 octets, this document updates the maximum allowed size of the Nonce to 128 octets. In addition, this document recommends that the OCSP requester and responder use a Nonce with a minimum length of 32 octets. 1.1. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 2. OCSP Extensions The message formats for OCSP requests and responses are defined in [RFC6960] and the Nonce extension was updated in [RFC8954]. [RFC6960] also defines the standard extensions for OCSP messages based on the extension model employed in X.509 version 3 certificates (see [RFC5280]). [RFC8954] replacesthis sectionSection 4.4.1 of [RFC6960] to limit the minimum and maximum length for the Nonce value. This document extends the maximum allowed nonce length to 128 octets and does not change the specifications of any of the otherstandardextensions defined in [RFC6960]. 2.1. 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; in responses, itwould beis included as one of the responseExtensions. In both the request and the response, the Noncewill beis identified by the object identifierid-pkix-ocsp- nonce,id-pkix-ocsp-nonce, while the extnValue is the encoded value of Nonce. If the Nonce extension is present, then the length of the Nonce MUST be at least 1 octet and can be up to 128 octets.[RFC8954]Implementations compliantimplementationswith [RFC8954] will not beunableable to process nonces generated per the new specification with sizes in excess of the limitof 32 octets that was(32 octets) specified in [RFC8954]. An OCSP requester that implements the extension in this document MUST use a minimum length of 32 octets for Nonce in the Nonce extension. An OCSP responder, supportingthat supports the Nonceextension,extension MUST accept Nonce lengths of at least 16 octets and up to and including 32 octets.ResponderA responder MAY choose to respond without the Nonce extension for requestswherein which the length of the Nonce is in between 1 octet and 15 octets or 33 octets and 128 octets.Responders,Responders thatimplementsimplement the extension in this document MUST reject any OCSP request that has a Nonce with a length of either 0 octets ormoregreater than 128 octets, with the malformedRequest OCSPResponseStatus as described in Section 4.2.1 of [RFC6960]. The value of the Nonce MUST be generated using a cryptographically strong pseudorandom number generator (see [RFC4086]). The minimum Nonce length of 1 octet is defined to provide backward compatibility with older OCSPrequesterrequesters that follow [RFC6960]. id-pkix-ocsp OBJECT IDENTIFIER ::= { id-ad-ocsp } id-pkix-ocsp-nonce OBJECT IDENTIFIER ::= { id-pkix-ocsp 2 } Nonce ::= OCTET STRING(SIZE(1..128))ExampleThe following is an example of an encoded OCSP Nonce extension with32 octeta 32-octet Nonce in hexadecimal format. 30 2f 06 09 2b 06 01 05 05 07 30 01 02 04 22 04 20 dd 49 d4 07 2c 44 9d a1 c3 17 bd 1c 1b df fe db e1 50 31 2e c4 cd 0a dd 18 e5 bd 6f 84 bf 14 c8 Here is the decoded version of the above example. Offset,LengthLength, and Object Identifier are in decimal. Offset Length 0 47 : SEQUENCE { 2 9 : OBJECT IDENTIFIER ocspNonce : (1 3 6 1 5 5 7 48 1 2) 13 34 : OCTET STRING, encapsulates { 15 32 : OCTET STRING : DD 49 D4 07 2C 44 9D A1 C3 17 BD 1C 1B DF FE DB : E1 50 31 2E C4 CD 0A DD 18 E5 BD 6F 84 BF 14 C8 : } : } 3. Security Considerations The security considerations of OCSP, in general, are described in [RFC6960]. During the interval in which the previous OCSP response for a certificate is not expired but the responder has a changed status for that certificate, a copy of that OCSP response can be used to indicate that the status of the certificate is still valid. Including a requester's nonce value in the OCSP responsemakes sureensures that the response is thelatestmost recent response from the server and not an old copy. 3.1. Replay Attack The Nonce extension is used to avoid replay attacks. Since the OCSP responder may choose not to send the Nonce extension in the OCSP response even if the requester has sent the Nonce extension in the request [RFC5019], an on-path attacker can intercept the OCSP request and respond with an earlier response from the server without the Nonce extension. This can be mitigated by configuring the server to use a short time interval between the thisUpdate and nextUpdate fields in the OCSP response. 4. IANA Considerations For the ASN.1Module in Appendix A.1, IANA is requested to assign an object identifier (OID) for the module identifier to replace TBD1. The OID for the module should be allocatedmodules inthe "SMI Security for PKIX Module Identifier" registry (1.3.6.1.5.5.7.0),Appendixes A.1 andthe Description for the new OID should be set to "id-mod-ocsp-2024-88". For the ASN.1 Module in AppendixA.2, IANAis requested to assign an object identifier (OID) for the module identifier to replace TBD2. The OID forhas assigned themodule should be allocatedfollowing object identifiers (OIDs) in the "SMI Security for PKIX Module Identifier" registry(1.3.6.1.5.5.7.0), and the(1.3.6.1.5.5.7.0): +=======+=====================+ | Value | Descriptionfor the new OID should be set to "id-mod-ocsp-2024-08". Acknowledgements The authors of this document wish to thank Mohit Sahni for his work to produce [RFC8954]. The authors wish to thank Russ Housley, Corey Bonnell, Michael StJohns and Carl Wallace for the feedback and suggestions.| +=======+=====================+ | 111 | id-mod-ocsp-2024-88 | +-------+---------------------+ | 112 | id-mod-ocsp-2024-08 | +-------+---------------------+ Table 1 5. References 5.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <https://www.rfc-editor.org/info/rfc2119>. [RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, "Randomness Requirements for Security", BCP 106, RFC 4086, DOI 10.17487/RFC4086, June 2005, <https://www.rfc-editor.org/info/rfc4086>. [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, <https://www.rfc-editor.org/info/rfc5019>. [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, DOI 10.17487/RFC5280, May 2008, <https://www.rfc-editor.org/info/rfc5280>. [RFC6960] Santesson, S., Myers, M., Ankney, R., Malpani, A., Galperin, S., and C. Adams, "X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSP", RFC 6960, DOI 10.17487/RFC6960, June 2013, <https://www.rfc-editor.org/info/rfc6960>. [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, <https://www.rfc-editor.org/info/rfc8174>. [RFC8954] Sahni, M., Ed., "Online Certificate Status Protocol (OCSP) Nonce Extension", RFC 8954, DOI 10.17487/RFC8954, November 2020, <https://www.rfc-editor.org/info/rfc8954>. 5.2. Informative References [Err5891] RFC Errata, Erratum ID 5891, RFC 6960, <https://www.rfc-editor.org/errata/eid5891>. [RFC5912] Hoffman, P. and J. Schaad, "New ASN.1 Modules for the Public Key Infrastructure Using X.509 (PKIX)", RFC 5912, DOI 10.17487/RFC5912, June 2010, <https://www.rfc-editor.org/info/rfc5912>.[Errata5891] RFC Errata, Erratum ID 5891, RFC 6960, <https://www.rfc-editor.org/errata/eid5891>.Appendix A. ASN.1 Modules This section includes the ASN.1 modules for OCSP and replaces theentirityentirety of Section 5 of [RFC8954]. It addresses ErrataidID 5891[Errata5891][Err5891] as well. Appendix A.1 includes an ASN.1 module that conforms to the 1998 version of ASN.1 for all syntax elements of OCSP. This module replaces themodulesmodule in Appendix B.1 of [RFC6960]. Appendix A.2 includes an ASN.1 module, corresponding to the module present in Appendix A.1, that conforms to the 2008 version of ASN.1. This module replaces the modules in Section 4 of [RFC5912] and Appendix B.2 of [RFC6960]. Although a 2008 ASN.1 module is provided, the module in Appendix A.1 remains the normative moduleasper the policy of the PKIXworking group.Working Group. A.1. OCSP in ASN.1 - 1998 Syntax <CODE BEGINS> OCSP-2024-88{iso(1){ iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)id-mod-ocsp-2024-88(TBD1)}id-mod-ocsp-2024-88(111) } DEFINITIONS EXPLICIT TAGS ::= BEGIN IMPORTS-- PKIX Certificate ExtensionsAuthorityInfoAccessSyntax, CRLReason, GeneralName FROM PKIX1Implicit88 -- From [RFC5280] { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0) id-pkix1-implicit(19) } Name, CertificateSerialNumber, Extensions, id-kp, id-ad-ocsp, Certificate, AlgorithmIdentifier FROM PKIX1Explicit88 -- From [RFC5280] { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0) id-pkix1-explicit(18)};} ; OCSPRequest ::= SEQUENCE { tbsRequest TBSRequest, optionalSignature [0] EXPLICIT Signature OPTIONAL } TBSRequest ::= SEQUENCE { version [0] EXPLICIT Version DEFAULT v1, requestorName [1] EXPLICIT GeneralName OPTIONAL, requestList SEQUENCE OF Request, requestExtensions [2] EXPLICIT Extensions OPTIONAL } Signature ::= SEQUENCE { signatureAlgorithm AlgorithmIdentifier, signature BIT STRING, certs [0] EXPLICIT SEQUENCE OF Certificate OPTIONAL } Version ::= INTEGER { v1(0) } Nonce ::= OCTETSTRING(SIZE(1..128))STRING (SIZE(1..128)) Request ::= SEQUENCE { reqCert CertID, singleRequestExtensions [0] EXPLICIT Extensions OPTIONAL } CertID ::= SEQUENCE { hashAlgorithm AlgorithmIdentifier, issuerNameHash OCTET STRING, -- Hash of issuer's DN issuerKeyHash OCTET STRING, -- Hash of issuer's public key serialNumber CertificateSerialNumber } OCSPResponse ::= SEQUENCE { responseStatus OCSPResponseStatus, responseBytes [0] EXPLICIT ResponseBytes OPTIONAL } OCSPResponseStatus ::= ENUMERATED { successful (0), -- Response has valid confirmations malformedRequest (1), -- Illegal confirmation request internalError (2), -- Internal error in issuer tryLater (3), -- Try again later -- (4) is not used sigRequired (5), -- Must sign the request unauthorized (6) -- Request unauthorized } ResponseBytes ::= SEQUENCE { responseType OBJECT IDENTIFIER, response OCTET STRING } BasicOCSPResponse ::= SEQUENCE { tbsResponseData ResponseData, signatureAlgorithm AlgorithmIdentifier, signature BIT STRING, certs [0] EXPLICIT SEQUENCE OF Certificate OPTIONAL } ResponseData ::= SEQUENCE { version [0] EXPLICIT Version DEFAULT v1, responderID ResponderID, producedAt GeneralizedTime, -- The format for--GeneralizedTime isas-- as specified in Section--4.1.2.5.2of-- [RFC5280] responses SEQUENCE OF SingleResponse, responseExtensions [1] EXPLICIT Extensions OPTIONAL } ResponderID ::= CHOICE { byName [1] Name, byKey [2] KeyHash } KeyHash ::= OCTET STRING -- SHA-1 hash of responder's public key--(i.e., the -- SHA-1 hash of the value of the--BIT STRING -- subjectPublicKey [excluding--the tag, length, and -- number of unused--bits] in the responder's -- certificate) SingleResponse ::= SEQUENCE { certID CertID, certStatus CertStatus, thisUpdate GeneralizedTime, nextUpdate [0] EXPLICIT GeneralizedTime OPTIONAL, singleExtensions [1] EXPLICIT Extensions OPTIONAL } CertStatus ::= CHOICE { good [0] IMPLICIT NULL, revoked [1] IMPLICIT RevokedInfo, unknown [2] IMPLICIT UnknownInfo } RevokedInfo ::= SEQUENCE { revocationTime GeneralizedTime, revocationReason [0] EXPLICIT CRLReason OPTIONAL } UnknownInfo ::= NULL ArchiveCutoff ::= GeneralizedTime AcceptableResponses ::= SEQUENCE OF OBJECT IDENTIFIER ServiceLocator ::= SEQUENCE { issuer Name, locator AuthorityInfoAccessSyntax } CrlID ::= SEQUENCE { crlUrl [0] EXPLICIT IA5String OPTIONAL, crlNum [1] EXPLICIT INTEGER OPTIONAL, crlTime [2] EXPLICIT GeneralizedTime OPTIONAL } PreferredSignatureAlgorithms ::= SEQUENCE OF PreferredSignatureAlgorithm PreferredSignatureAlgorithm ::= SEQUENCE { sigIdentifier AlgorithmIdentifier, certIdentifier AlgorithmIdentifier OPTIONAL } -- Object Identifiers id-kp-OCSPSigning OBJECT IDENTIFIER ::= { id-kp 9 } id-pkix-ocsp OBJECT IDENTIFIER ::= { id-ad-ocsp } id-pkix-ocsp-basic OBJECT IDENTIFIER ::= { id-pkix-ocsp 1 } id-pkix-ocsp-nonce OBJECT IDENTIFIER ::= { id-pkix-ocsp 2 } id-pkix-ocsp-crl OBJECT IDENTIFIER ::= { id-pkix-ocsp 3 } id-pkix-ocsp-response OBJECT IDENTIFIER ::= { id-pkix-ocsp 4 } id-pkix-ocsp-nocheck OBJECT IDENTIFIER ::= { id-pkix-ocsp 5 } id-pkix-ocsp-archive-cutoff OBJECT IDENTIFIER ::= { id-pkix-ocsp 6 } id-pkix-ocsp-service-locator OBJECT IDENTIFIER ::= { id-pkix-ocsp 7 } id-pkix-ocsp-pref-sig-algs OBJECT IDENTIFIER ::= { id-pkix-ocsp 8 } id-pkix-ocsp-extended-revoke OBJECT IDENTIFIER ::= { id-pkix-ocsp 9 } END <CODE ENDS> A.2. OCSP in ASN.1 - 2008 Syntax <CODE BEGINS> OCSP-2024-08{iso(1){ iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)id-mod-ocsp-2024-08(TBD2)}id-mod-ocsp-2024-08(112) } DEFINITIONS EXPLICIT TAGS ::= BEGIN IMPORTS Extensions{}, EXTENSION FROM PKIX-CommonTypes-2009 -- From [RFC5912]{iso(1){ iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)id-mod-pkixCommon-02(57)}id-mod-pkixCommon-02(57) } AlgorithmIdentifier{}, DIGEST-ALGORITHM, SIGNATURE-ALGORITHM, PUBLIC-KEY FROM AlgorithmInformation-2009 -- From [RFC5912]{iso(1){ iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)id-mod-algorithmInformation-02(58)}id-mod-algorithmInformation-02(58) } AuthorityInfoAccessSyntax, GeneralName, CrlEntryExtensions, CRLReason FROM PKIX1Implicit-2009 -- From [RFC5912]{iso(1){ iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)id-mod-pkix1-implicit-02(59)}id-mod-pkix1-implicit-02(59) } Name, Certificate, CertificateSerialNumber, id-kp,id-ad-ocsp, Certificateid-ad-ocsp FROM PKIX1Explicit-2009 -- From [RFC5912]{iso(1){ iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)id-mod-pkix1-explicit-02(51)}id-mod-pkix1-explicit-02(51) } sa-dsaWithSHA1, sa-rsaWithMD2, sa-rsaWithMD5, sa-rsaWithSHA1 FROM PKIXAlgs-2009 -- From [RFC5912]{iso(1){ iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)id-mod-pkix1-algorithms2008-02(56)};id-mod-pkix1-algorithms2008-02(56) } ; OCSPRequest ::= SEQUENCE { tbsRequest TBSRequest, optionalSignature [0] EXPLICIT Signature OPTIONAL } TBSRequest ::= SEQUENCE { version [0] EXPLICIT Version DEFAULT v1, requestorName [1] EXPLICIT GeneralName OPTIONAL, requestList SEQUENCE OF Request, requestExtensions [2] EXPLICIT Extensions{{re-ocsp-nonce{{ re-ocsp-nonce |re-ocsp-response, ..., re-ocsp-preferred-signature-algorithms}}re-ocsp-response | re-ocsp-preferred-signature-algorithms, ... }} OPTIONAL } Signature ::= SEQUENCE { signatureAlgorithm AlgorithmIdentifier { SIGNATURE-ALGORITHM, {...}}, signature BIT STRING, certs [0] EXPLICIT SEQUENCE OF Certificate OPTIONAL } Version ::= INTEGER { v1(0) } Nonce ::= OCTETSTRING(SIZE(1..128))STRING (SIZE(1..128)) Request ::= SEQUENCE { reqCert CertID, singleRequestExtensions [0] EXPLICIT Extensions{ {re-ocsp-service-locator, ...}}{{ re-ocsp-service-locator, ... }} OPTIONAL } CertID ::= SEQUENCE { hashAlgorithm AlgorithmIdentifier{DIGEST-ALGORITHM,{ DIGEST-ALGORITHM, {...}}, issuerNameHash OCTET STRING, -- Hash of issuer's DN issuerKeyHash OCTET STRING, -- Hash of issuer's public key serialNumber CertificateSerialNumber } OCSPResponse ::= SEQUENCE { responseStatus OCSPResponseStatus, responseBytes [0] EXPLICIT ResponseBytes OPTIONAL } OCSPResponseStatus ::= ENUMERATED { successful (0), -- Response has valid confirmations malformedRequest (1), -- Illegal confirmation request internalError (2), -- Internal error in issuer tryLater (3), -- Try again later -- (4) is not used sigRequired (5), -- Must sign the request unauthorized (6) -- Request unauthorized } RESPONSE ::= TYPE-IDENTIFIER ResponseSet RESPONSE ::={basicResponse, ...}{ basicResponse, ... } ResponseBytes ::= SEQUENCE { responseTypeRESPONSE. &idRESPONSE.&id ({ResponseSet}), response OCTET STRING (CONTAINING RESPONSE. &Type({ResponseSet}{@responseType}))} basicResponse RESPONSE ::= { BasicOCSPResponse IDENTIFIED BY id-pkix-ocsp-basic } BasicOCSPResponse ::= SEQUENCE { tbsResponseData ResponseData, signatureAlgorithmAlgorithmIdentifier{SIGNATURE-ALGORITHM, {sa-dsaWithSHA1AlgorithmIdentifier { SIGNATURE-ALGORITHM, { sa-dsaWithSHA1 | sa-rsaWithSHA1 | sa-rsaWithMD5 | sa-rsaWithMD2,...}},... }}, signature BIT STRING, certs [0] EXPLICIT SEQUENCE OF Certificate OPTIONAL } ResponseData ::= SEQUENCE { version [0] EXPLICIT Version DEFAULT v1, responderID ResponderID, producedAt GeneralizedTime, responses SEQUENCE OF SingleResponse, responseExtensions [1] EXPLICIT Extensions{{re-ocsp-nonce, ..., re-ocsp-extended-revoke}}{{ re-ocsp-nonce | re-ocsp-extended-revoke, ... }} OPTIONAL } ResponderID ::= CHOICE { byName [1] Name, byKey [2] KeyHash } KeyHash ::= OCTET STRING -- SHA-1 hash of responder's public key -- (excluding the tag and lengthfields)and number -- of unused bits) SingleResponse ::= SEQUENCE { certID CertID, certStatus CertStatus, thisUpdate GeneralizedTime, nextUpdate [0] EXPLICIT GeneralizedTime OPTIONAL, singleExtensions [1] EXPLICITExtensions{{re-ocsp-crlExtensions {{ re-ocsp-crl | re-ocsp-archive-cutoff | CrlEntryExtensions,...} }... }} OPTIONAL } CertStatus ::= CHOICE { good [0] IMPLICIT NULL, revoked [1] IMPLICIT RevokedInfo, unknown [2] IMPLICIT UnknownInfo } RevokedInfo ::= SEQUENCE { revocationTime GeneralizedTime, revocationReason [0] EXPLICIT CRLReason OPTIONAL } UnknownInfo ::= NULL ArchiveCutoff ::= GeneralizedTime AcceptableResponses ::= SEQUENCE OF RESPONSE.&id({ResponseSet}) ServiceLocator ::= SEQUENCE { issuer Name, locator AuthorityInfoAccessSyntax } CrlID ::= SEQUENCE { crlUrl [0] EXPLICIT IA5String OPTIONAL, crlNum [1] EXPLICIT INTEGER OPTIONAL, crlTime [2] EXPLICIT GeneralizedTime OPTIONAL } PreferredSignatureAlgorithms ::= SEQUENCE OF PreferredSignatureAlgorithm PreferredSignatureAlgorithm ::= SEQUENCE { sigIdentifierAlgorithmIdentifier{SIGNATURE-ALGORITHM, {...}},AlgorithmIdentifier { SIGNATURE-ALGORITHM, {...} }, certIdentifierAlgorithmIdentifier{PUBLIC-KEY,AlgorithmIdentifier {PUBLIC-KEY, {...}} OPTIONAL } -- Certificate Extensions ext-ocsp-nocheck EXTENSION ::= { SYNTAX NULL IDENTIFIED BY id-pkix-ocsp-nocheck } -- Request Extensions re-ocsp-nonce EXTENSION ::= { SYNTAX Nonce IDENTIFIED BY id-pkix-ocsp-nonce } re-ocsp-response EXTENSION ::= { SYNTAX AcceptableResponses IDENTIFIED BY id-pkix-ocsp-response } re-ocsp-service-locator EXTENSION ::= { SYNTAX ServiceLocator IDENTIFIED BY id-pkix-ocsp-service-locator } re-ocsp-preferred-signature-algorithms EXTENSION ::= { SYNTAX PreferredSignatureAlgorithms IDENTIFIED BY id-pkix-ocsp-pref-sig-algs } -- Response Extensions re-ocsp-crl EXTENSION ::= { SYNTAX CrlID IDENTIFIED BY id-pkix-ocsp-crl } re-ocsp-archive-cutoff EXTENSION ::= { SYNTAX ArchiveCutoff IDENTIFIED BY id-pkix-ocsp-archive-cutoff } re-ocsp-extended-revoke EXTENSION ::= { SYNTAX NULL IDENTIFIED BY id-pkix-ocsp-extended-revoke } -- Object Identifiers id-kp-OCSPSigning OBJECT IDENTIFIER ::= { id-kp 9 } id-pkix-ocsp OBJECT IDENTIFIER ::= id-ad-ocsp id-pkix-ocsp-basic OBJECT IDENTIFIER ::= { id-pkix-ocsp 1 } id-pkix-ocsp-nonce OBJECT IDENTIFIER ::= { id-pkix-ocsp 2 } id-pkix-ocsp-crl OBJECT IDENTIFIER ::= { id-pkix-ocsp 3 } id-pkix-ocsp-response OBJECT IDENTIFIER ::= { id-pkix-ocsp 4 } id-pkix-ocsp-nocheck OBJECT IDENTIFIER ::= { id-pkix-ocsp 5 } id-pkix-ocsp-archive-cutoff OBJECT IDENTIFIER ::= { id-pkix-ocsp 6 } id-pkix-ocsp-service-locator OBJECT IDENTIFIER ::= { id-pkix-ocsp 7 } id-pkix-ocsp-pref-sig-algs OBJECT IDENTIFIER ::= { id-pkix-ocsp 8 } id-pkix-ocsp-extended-revoke OBJECT IDENTIFIER ::= { id-pkix-ocsp 9 } END <CODE ENDS> Acknowledgements The authors of this document thank Mohit Sahni for his work to produce [RFC8954]. The authors also thank Russ Housley, Corey Bonnell, Michael StJohns, Tomas Gustavsson, and Carl Wallace for their feedback and suggestions. Author's Address Himanshu Sharma (editor) Netskope Inc 2445 Augustine Dr 3rd floor Santa Clara, California 95054 United States of America Email: himanshu@netskope.com URI: www.netskope.com