CBOR Encoded Certificate Revocation Management
draft-liao-cose-c509-revocation-00
This document is an Internet-Draft (I-D).
Anyone may submit an I-D to the IETF.
This I-D is not endorsed by the IETF and has no formal standing in the
IETF standards process.
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Lijun Liao , Marco Tiloca , Joel Höglund , Rikard Höglund , Shahid Raza | ||
| Last updated | 2026-07-24 (Latest revision 2026-07-06) | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Additional resources |
GitHub Repository
|
||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-liao-cose-c509-revocation-00
COSE Working Group L. Liao
Internet-Draft NIO
Intended status: Standards Track M. Tiloca
Expires: 7 January 2027 J. Höglund
R. Höglund
RISE AB
S. Raza
University of Glasgow
6 July 2026
CBOR Encoded Certificate Revocation Management
draft-liao-cose-c509-revocation-00
Abstract
This document specifies CBOR-encoded PKI structures for use with C509
certificates (draft-ietf-cose-cbor-encoded-cert), X.509 certificates
(RFC 5280), and future certificate types. It defines C509 CRL and
C509 OCSP, compact CBOR encodings of X.509 Certificate Revocation
Lists (RFC 5280) and OCSP messages (RFC 6960), respectively. The
structures defined in this document are certificate-type agnostic and
can be used with C509 certificates, X.509 certificates, or future
certificate types without modification. C509 OCSP improves on RFC
6960 by signing a wider set of fields to prevent algorithm-
substitution and certificate-chain substitution attacks, replacing
plaintext serial numbers with hashes to preserve requestor privacy,
replacing the two-hash issuer identity with a single certificate
hash, and identifying all participants (requestor, responder, issuer)
by a uniform certificate hash rather than type-specific fields. C509
CRL and C509 OCSP are not wire-format-compatible with their DER-
encoded X.509 counterparts and cannot be converted to or from them
without semantic interpretation.
About This Document
This note is to be removed before publishing as an RFC.
Status information for this document may be found at
https://datatracker.ietf.org/doc/draft-liao-cose-c509-revocation/.
Discussion of this document takes place on the CBOR Object Signing
and Encryption (cose) Working Group mailing list
(mailto:cose@ietf.org), which is archived at
https://mailarchive.ietf.org/arch/browse/cose/. Subscribe at
https://www.ietf.org/mailman/listinfo/cose/.
Liao, et al. Expires 7 January 2027 [Page 1]
Internet-Draft C509 Revocation July 2026
Source for this draft and an issue tracker can be found at
https://github.com/lijun-nio/idc509rev.
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 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 7 January 2027.
Copyright Notice
Copyright (c) 2026 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 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 . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 7
3. Imported Definitions . . . . . . . . . . . . . . . . . . . . 7
4. Encoding of Time Fields . . . . . . . . . . . . . . . . . . . 8
5. C509 CRL . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 8
5.2. C509 CRL CDDL . . . . . . . . . . . . . . . . . . . . . . 8
5.3. Field Encodings . . . . . . . . . . . . . . . . . . . . . 9
5.3.1. CRLInfoData and C509CRLInfo . . . . . . . . . . . . . 10
5.3.2. crlType . . . . . . . . . . . . . . . . . . . . . . . 10
5.3.3. signatureAlgorithm . . . . . . . . . . . . . . . . . 10
5.3.4. authoritySubject and authorityKeyIdentifier . . . . . 10
Liao, et al. Expires 7 January 2027 [Page 2]
Internet-Draft C509 Revocation July 2026
5.3.5. crlNumber . . . . . . . . . . . . . . . . . . . . . . 11
5.3.6. thisUpdate and nextUpdate . . . . . . . . . . . . . . 11
5.3.7. baseCrlNumber . . . . . . . . . . . . . . . . . . . . 11
5.3.8. reasonCode Encoding . . . . . . . . . . . . . . . . . 11
5.3.9. revokedCertsList and PerIssuerRevokedCerts . . . . . 12
5.3.9.1. Design Considerations . . . . . . . . . . . . . . 12
5.3.9.2. Fields . . . . . . . . . . . . . . . . . . . . . 13
5.3.10. CRL Extensions . . . . . . . . . . . . . . . . . . . 16
5.3.11. Per-Issuer Extensions . . . . . . . . . . . . . . . . 17
5.3.11.1. expiredCertsOnCRL . . . . . . . . . . . . . . . 18
5.3.12. CRL Entry Extensions . . . . . . . . . . . . . . . . 18
5.3.13. signatureValue . . . . . . . . . . . . . . . . . . . 19
6. C509 OCSP . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 20
6.2. Identification of Certificates . . . . . . . . . . . . . 20
6.3. C509 OCSP Request . . . . . . . . . . . . . . . . . . . . 21
6.3.1. CDDL . . . . . . . . . . . . . . . . . . . . . . . . 21
6.3.2. Field Encodings . . . . . . . . . . . . . . . . . . . 22
6.3.2.1. ocspRequestType . . . . . . . . . . . . . . . . . 22
6.3.2.2. issuerCertHash . . . . . . . . . . . . . . . . . 22
6.3.2.3. PerIssuerOCSPRequests, PerIssuerOCSPRequest,
SingleCertRequests and SingleCertRequest . . . . . 23
6.3.2.4. C509UnsignedOCSPRequest . . . . . . . . . . . . . 24
6.3.2.5. C509SignedOCSPRequest . . . . . . . . . . . . . . 24
6.3.2.6. C509SimpleOCSPRequest . . . . . . . . . . . . . . 25
6.4. C509 OCSP Response . . . . . . . . . . . . . . . . . . . 25
6.4.1. CDDL . . . . . . . . . . . . . . . . . . . . . . . . 25
6.4.2. Field Encodings . . . . . . . . . . . . . . . . . . . 27
6.4.2.1. C509ErrorOCSPResponse . . . . . . . . . . . . . . 27
6.4.2.2. C509BasicOCSPResponse . . . . . . . . . . . . . . 28
6.4.2.3. C509SimpleOCSPResponse . . . . . . . . . . . . . 28
6.4.2.4. nonce . . . . . . . . . . . . . . . . . . . . . . 30
6.4.2.5. responderCertHash . . . . . . . . . . . . . . . . 30
6.4.2.6. responderCerts . . . . . . . . . . . . . . . . . 30
6.4.2.7. signatureAlgorithm and signatureValue . . . . . . 30
6.4.2.8. producedAt, thisUpdate, nextUpdate . . . . . . . 31
6.4.2.9. extensions . . . . . . . . . . . . . . . . . . . 31
6.4.2.10. PerIssuerOCSPResponses and
PerIssuerOCSPResponse . . . . . . . . . . . . . . . 31
6.4.2.11. SingleCertResponse . . . . . . . . . . . . . . . 31
6.4.2.12. Per-Issuer OCSP Extensions . . . . . . . . . . . 32
6.4.2.13. OCSP Extensions . . . . . . . . . . . . . . . . . 33
6.5. Certificate Type Interoperability . . . . . . . . . . . . 36
6.6. OCSP Stapling in TLS . . . . . . . . . . . . . . . . . . 37
7. C509 Hash Algorithms . . . . . . . . . . . . . . . . . . . . 38
8. Security Considerations . . . . . . . . . . . . . . . . . . . 39
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 39
9.1. Extension Identifiers Registry . . . . . . . . . . . . . 40
Liao, et al. Expires 7 January 2027 [Page 3]
Internet-Draft C509 Revocation July 2026
9.2. C509 Hash Algorithms Registry . . . . . . . . . . . . . . 40
9.3. TLS CertificateStatusType Registry . . . . . . . . . . . 42
9.4. Media Type Application Registry . . . . . . . . . . . . . 42
9.4.1. Media Type application/c509-crl+cbor . . . . . . . . 42
9.4.2. Media Type application/c509-crlinfo+cbor . . . . . . 43
9.4.3. Media Type application/c509-ocspreq+cbor . . . . . . 44
9.4.4. Media Type application/c509-ocspresp+cbor . . . . . . 45
9.5. CoAP Content-Formats Registry . . . . . . . . . . . . . . 46
9.6. Expert Review Guidelines . . . . . . . . . . . . . . . . 46
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 46
10.1. Normative References . . . . . . . . . . . . . . . . . . 46
10.2. Informative References . . . . . . . . . . . . . . . . . 48
Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 49
A.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 49
A.2. Helper Keys and Certificates . . . . . . . . . . . . . . 50
A.2.1. CA Private Key and Certificate . . . . . . . . . . . 50
A.2.1.1. CA Private Key . . . . . . . . . . . . . . . . . 50
A.2.1.2. CA Certificate . . . . . . . . . . . . . . . . . 51
A.2.2. CRL Signer Private Key and Certificate . . . . . . . 52
A.2.2.1. CRL Signer Private Key . . . . . . . . . . . . . 52
A.2.2.2. CRL Signer Certificate . . . . . . . . . . . . . 52
A.2.3. OCSP Requestor Private Key and Certificate . . . . . 53
A.2.3.1. OCSP Requestor Private Key . . . . . . . . . . . 53
A.2.3.2. OCSP Requestor Certificate . . . . . . . . . . . 53
A.2.4. OCSP Responder Private Key and Certificate . . . . . 54
A.2.4.1. OCSP Responder Private Key . . . . . . . . . . . 54
A.2.4.2. OCSP Responder Certificate . . . . . . . . . . . 55
A.3. CRL Examples . . . . . . . . . . . . . . . . . . . . . . 56
A.3.1. CRL Example Without Revoked Certificates . . . . . . 56
A.3.1.1. X.509 CRL . . . . . . . . . . . . . . . . . . . . 56
A.3.1.2. C509 CRL . . . . . . . . . . . . . . . . . . . . 56
A.3.2. CRL Example With Revoked Certificates . . . . . . . . 57
A.3.2.1. X.509 CRL . . . . . . . . . . . . . . . . . . . . 58
A.3.2.2. C509 CRL . . . . . . . . . . . . . . . . . . . . 58
A.3.3. Delta CRL Example With Revoked Certificates . . . . . 61
A.3.3.1. X.509 CRL . . . . . . . . . . . . . . . . . . . . 61
A.3.3.2. C509 CRL . . . . . . . . . . . . . . . . . . . . 61
A.3.4. Indirect CRL Example With Revoked Certificates . . . 63
A.3.4.1. X.509 CRL . . . . . . . . . . . . . . . . . . . . 64
A.3.4.2. C509 CRL . . . . . . . . . . . . . . . . . . . . 64
A.4. OCSP Request Examples . . . . . . . . . . . . . . . . . . 67
A.4.1. Simple OCSP Request Example . . . . . . . . . . . . . 67
A.4.1.1. X.509 OCSP Request . . . . . . . . . . . . . . . 67
A.4.1.2. C509 OCSP Request . . . . . . . . . . . . . . . . 67
A.4.2. Unsigned OCSP Request Example . . . . . . . . . . . . 68
A.4.2.1. X.509 OCSP Request . . . . . . . . . . . . . . . 68
A.4.2.2. C509 OCSP Request . . . . . . . . . . . . . . . . 69
Liao, et al. Expires 7 January 2027 [Page 4]
Internet-Draft C509 Revocation July 2026
A.4.3. Signed OCSP Request Example Without Requestor's
Certificate . . . . . . . . . . . . . . . . . . . . . 71
A.4.3.1. X.509 OCSP Request . . . . . . . . . . . . . . . 72
A.4.3.2. C509 OCSP Request . . . . . . . . . . . . . . . . 72
A.4.4. Signed OCSP Request Example With Requestor's
Certificate . . . . . . . . . . . . . . . . . . . . . 75
A.4.4.1. X.509 OCSP Request . . . . . . . . . . . . . . . 75
A.4.4.2. C509 OCSP Request . . . . . . . . . . . . . . . . 75
A.4.5. Signed OCSP Request Example With Requestor's
Certificate Chain . . . . . . . . . . . . . . . . . . 79
A.4.5.1. X.509 OCSP Request . . . . . . . . . . . . . . . 79
A.4.5.2. C509 OCSP Request . . . . . . . . . . . . . . . . 80
A.5. OCSP Response Examples . . . . . . . . . . . . . . . . . 84
A.5.1. Error OCSP Response Example . . . . . . . . . . . . . 85
A.5.1.1. X.509 OCSP Response . . . . . . . . . . . . . . . 85
A.5.1.2. C509 OCSP Response . . . . . . . . . . . . . . . 85
A.5.2. Simple OCSP Response Example . . . . . . . . . . . . 85
A.5.2.1. X.509 OCSP Response . . . . . . . . . . . . . . . 86
A.5.2.2. C509 OCSP Response . . . . . . . . . . . . . . . 86
A.5.3. Basic OCSP Response Example Without Responder's
Certificate . . . . . . . . . . . . . . . . . . . . . 88
A.5.3.1. X.509 OCSP Response . . . . . . . . . . . . . . . 88
A.5.3.2. C509 OCSP Response . . . . . . . . . . . . . . . 89
A.5.4. Basic OCSP Response Example With Responder's
Certificate . . . . . . . . . . . . . . . . . . . . . 92
A.5.4.1. X.509 OCSP Response . . . . . . . . . . . . . . . 92
A.5.4.2. C509 OCSP Response . . . . . . . . . . . . . . . 93
A.5.5. Basic OCSP Response Example With Responder's
Certificate Chain . . . . . . . . . . . . . . . . . . 97
A.5.5.1. X.509 OCSP Response . . . . . . . . . . . . . . . 97
A.5.5.2. C509 OCSP Response . . . . . . . . . . . . . . . 98
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 103
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 103
1. Introduction
Public Key Infrastructure (PKI) for constrained environments
[RFC7228] requires compact certificate representations and compact
revocation information. [I-D.ietf-cose-cbor-encoded-cert] defines
C509 certificates, a CBOR encoding of X.509 certificates [RFC5280]
that reduces certificate size by over 50% for typical constrained-
device profiles. However, revocation mechanisms -- Certificate
Revocation Lists (CRLs) and Online Certificate Status Protocol (OCSP)
messages -- have not yet received the same treatment.
CRLs as defined in [RFC5280] can be large, especially when many
certificates have been revoked or when CRL extensions add overhead.
OCSP responses as defined in [RFC6960] carry per-certificate status
Liao, et al. Expires 7 January 2027 [Page 5]
Internet-Draft C509 Revocation July 2026
information and may be exchanged during TLS [RFC8446] and DTLS
[RFC9147] handshakes via OCSP stapling [RFC6066], directly affecting
handshake latency.
Note on terminology: The label "C509" is used for consistency with
the C509 certificate encoding and to promote a cohesive C509 PKI
ecosystem (C509 certificates, CRLs, OCSP, and related tooling).
Although this document uses "C509" in its names, the encodings and
protocols defined here are certificate-type agnostic and apply
equally to X.509 certificates and other certificate types; see
Section 6.5.
This document specifies:
* *C509 CRL* -- a natively signed CBOR [RFC8949] encoding of X.509
CRLs ([RFC5280], Section 5). The signature is computed over the
CBOR Sequence [RFC8742] TBSCertList; no ASN.1 encoding is
involved.
* *C509 OCSP* -- a CBOR encoding of OCSP requests and responses
([RFC6960]). The encoding compresses common fields while
preserving semantic equivalence. Four key improvements are made
over [RFC6960]:
- The signature in signed requests and responses is computed over
a wider set of fields than in [RFC6960], including the
signature algorithm and the certificate chain, preventing
algorithm-substitution and certificate-chain substitution
attacks.
- Certificate serial numbers in requests and responses are
replaced by hashes (serialNumberHash), providing privacy
against passive observers who do not already know the queried
serial numbers.
- The issuer is identified by a single hash over the issuer
certificate (issuerCertHash) rather than by the two-hash
CertID, reducing per-issuer overhead.
- All participants -- requestor, responder, and issuer -- are
identified by a hash over their certificate (requestorCertHash,
responderCertHash, issuerCertHash) rather than by a plaintext
Subject distinguished name or SubjectKeyIdentifier, avoiding
structural CHOICE types such as the X.509 ResponderID (byName
or byKey) and simplifying support for different certificate
types (e.g., C509, X.509, or future types) because the same
hash applies regardless of the certificate encoding.
Liao, et al. Expires 7 January 2027 [Page 6]
Internet-Draft C509 Revocation July 2026
See the field encoding sections of this document for details.
The request and response structures defined in this document are
certificate-type agnostic: they can be used with C509
certificates, X.509 certificates, or any future certificate type
without modification; see Section 6.5.
C509 CRL and C509 OCSP apply the same compression techniques as C509
certificates: static fields are elided, OIDs are replaced with short
integers, time values are compressed to POSIX timestamps, and
redundant encoding is removed. Implementers may use the CBOR
playground [CborMe] to inspect encoded examples.
C509 CRL and C509 OCSP are not wire-format-compatible with their DER-
encoded counterparts defined in [RFC5280] and [RFC6960]. Systems
that use C509 CRL or C509 OCSP must explicitly support these CBOR-
encoded formats; they cannot be transparently substituted for or
derived from the corresponding DER-encoded structures.
C509 CRL and C509 OCSP are designed to be compatible with certificate
profiles for constrained deployments, such as [RFC7925].
2. Terminology
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.
This document uses the terminology from [RFC5280], [RFC6960],
[RFC7228], [RFC8610], [RFC8742], [RFC8949], and [RFC9682]. Unless
otherwise stated, "CBOR" refers to deterministically encoded CBOR as
specified in Sections 4.2.1 and 4.2.2 of [RFC8949].
3. Imported Definitions
The following types are imported from
[I-D.ietf-cose-cbor-encoded-cert]:
* Name: no limitation.
* Extensions: only the ( extensionID: int, extensionValue: Defined )
choice of Extension is permitted.
* COSE_C509: no limitation.
* AlgorithmIdentifier: no limitation.
Liao, et al. Expires 7 January 2027 [Page 7]
Internet-Draft C509 Revocation July 2026
The following type is imported from [RFC9360]:
* COSE_X509: no limitation.
This document further defines the following constrained alias for use
in all CDDL definitions:
IntAlgorithmIdentifier = int
IntAlgorithmIdentifier is the int-only instantiation of
AlgorithmIdentifier from [I-D.ietf-cose-cbor-encoded-cert]. It is
used throughout this document wherever an algorithm identifier
appears in the wire encoding.
4. Encoding of Time Fields
Time fields are encoded as unwrapped CBOR epoch-based date/time
(~time). The tag content MUST be a non-negative integer. In POSIX
time [POSIX], leap seconds are ignored; a leap second has the same
POSIX time as the second before it.
5. C509 CRL
5.1. Overview
A C509 CRL is a natively signed CBOR [RFC8949] encoding of an X.509
v2 CRL as defined in [RFC5280], Section 5. The signature is computed
over the CBOR Sequence [RFC8742] TBSCertList; no ASN.1 encoding is
involved. A C509 CRL preserves the semantics of the corresponding
DER-encoded X.509 CRL for the subset of RFC 5280 structures supported
by this document.
A C509 CRL is not wire-format-compatible with a DER-encoded X.509
CRL. The two formats cannot be mechanically converted to or from
each other without semantic interpretation of the contained data.
5.2. C509 CRL CDDL
The following CDDL defines the top-level C509CRL structure and the
TBSCertList sequence:
Liao, et al. Expires 7 January 2027 [Page 8]
Internet-Draft C509 Revocation July 2026
C509CRL = [
TBSCertList,
signatureValue : any,
]
TBSCertList = (
CRLInfoData,
revokedCertsList : [+ PerIssuerRevokedCerts] / null
)
C509CRLInfo = [ CRLInfoData ]
CRLInfoData = (
crlType : uint, ; 0 = C509CRL
signatureAlgorithm : IntAlgorithmIdentifier,
authoritySubject : Name / #6.121(bytes),
authorityKeyIdentifier : bytes / null,
crlNumber : uint,
thisUpdate : ~time,
nextUpdate : uint / null,
baseCrlNumber : uint / null,
crlExtensions : Extensions,
)
PerIssuerRevokedCerts = (
issuer : Name / #6.121(bytes) / null,
revokedCertsControl : RevokedCertsControl / null,
extensions : Extensions,
revokedCerts : bytes / null,
removedFromCRLCerts : bytes / null,
)
RevokedCertsControl = [
flags : uint,
serialNumberLength : uint,
dateLength : uint,
baseDate : ~time,
]
Figure 1: CDDL for C509CRL
5.3. Field Encodings
Liao, et al. Expires 7 January 2027 [Page 9]
Internet-Draft C509 Revocation July 2026
5.3.1. CRLInfoData and C509CRLInfo
CRLInfoData is a CDDL group that carries all CRL fields except
revokedCertsList. C509CRLInfo is the standalone CBOR array form of
CRLInfoData; it can be used to convey CRL freshness information
(crlType, signature algorithm, issuer identity, CRL number, validity
window, extensions) without the potentially large revocation list.
TBSCertList embeds CRLInfoData and adds revokedCertsList.
5.3.2. crlType
The crlType field serves as the type discriminator for C509CRL,
following the same extensibility pattern as ocspRequestType and
ocspResponseType. This document defines only type 0, corresponding
to the C509CRL structure. Future specifications may define
additional types by assigning new integer values.
5.3.3. signatureAlgorithm
Encoded identically to the int choice of issuerSignatureAlgorithm in
C509 certificates (see [I-D.ietf-cose-cbor-encoded-cert],
Section 3.1.11). Algorithm integer values are from the same registry
used for C509 certificates.
Unlike in [RFC5280], where the signature algorithm appears outside
the TBSCertList and is therefore not covered by the CRL signature,
signatureAlgorithm is part of CRLInfoData within TBSCertList and is
therefore covered by the signature. This prevents algorithm-
substitution attacks on the CRL.
5.3.4. authoritySubject and authorityKeyIdentifier
The authoritySubject and authorityKeyIdentifier fields identify the
CRL authority.
The authoritySubject field identifies the subject of the CRL issuer.
When the CRL is issued by a C509 CA, authoritySubject is a Name value
identical to the subject field of the authority C509 certificate.
When the CRL is issued by an X.509 CA (e.g., in a hybrid deployment
where a legacy CA issues a C509-format CRL), authoritySubject is
encoded as #6.121(bytes), where the byte string contains the DER-
encoded Name from the subject field of the issuing X.509 CA
certificate ([X.690]).
The authorityKeyIdentifier field is identical to the value of the
authority's subjectKeyIdentifier extension. This field corresponds
to the X.509 CRL extension authorityKeyIdentifier ([RFC5280],
Section 5.2.1). It is promoted to a dedicated field because it MUST
Liao, et al. Expires 7 January 2027 [Page 10]
Internet-Draft C509 Revocation July 2026
be present in conforming X.509 CRLs and because making it explicit
simplifies the structure and reduces encoded size compared to
representing it as a generic extension.
5.3.5. crlNumber
The crlNumber field is encoded as an unsigned integer (uint). It
corresponds to the cRLNumber extension in [RFC5280], Section 5.2.3,
which this document replaces with a dedicated field. The value is
monotonically increasing for both full and delta CRLs.
5.3.6. thisUpdate and nextUpdate
The thisUpdate field is encoded as described in Section 4. The
nextUpdate field is encoded as a uint representing the number of
seconds from thisUpdate until the next CRL is expected to be issued.
It is encoded as null when no next update time is known.
5.3.7. baseCrlNumber
The baseCrlNumber field is encoded as null for a full CRL. For a
delta CRL, it contains the CRL number of the corresponding base full
CRL.
5.3.8. reasonCode Encoding
The reasonCode ENUMERATED value is encoded as one unsigned byte. The
byte values are aligned with the ENUMERATED values of the CRLReason
type defined in [RFC5280], Section 5.3.1; a C509 revocationReason
byte value equals the corresponding ASN.1 ENUMERATED integer value
for the same reason code.
Liao, et al. Expires 7 January 2027 [Page 11]
Internet-Draft C509 Revocation July 2026
+======+======================+
| Byte | reasonCode |
+======+======================+
| 0x00 | unspecified |
+------+----------------------+
| 0x01 | keyCompromise |
+------+----------------------+
| 0x02 | cACompromise |
+------+----------------------+
| 0x03 | affiliationChanged |
+------+----------------------+
| 0x04 | superseded |
+------+----------------------+
| 0x05 | cessationOfOperation |
+------+----------------------+
| 0x06 | certificateHold |
+------+----------------------+
| - | removeFromCRL |
+------+----------------------+
| 0x09 | privilegeWithdrawn |
+------+----------------------+
| 0x0A | aACompromise |
+------+----------------------+
Table 1: reasonCode encoding
removeFromCRL (enumeration value 0x08) is not encoded in
revokedCerts. Certificates removed from the CRL are instead
indicated in the removedFromCRLCerts field of PerIssuerRevokedCerts.
5.3.9. revokedCertsList and PerIssuerRevokedCerts
5.3.9.1. Design Considerations
In X.509 CRLs ([RFC5280], Section 5.3.3), an indirect CRL uses the
certificateIssuer CRL entry extension to indicate that a revocation
entry — and all subsequent entries — belong to a different issuer.
This mechanism has two significant drawbacks: (1) it is implicit and
positional, making it difficult to parse correctly and error-prone to
implement; and (2) it is impossible to represent an issuer that has
no currently revoked certificates (e.g., to carry per-issuer
extensions or to explicitly indicate that the issuer is known but has
an empty revocation list), because there is no entry to attach the
certificateIssuer extension to.
PerIssuerRevokedCerts solves both problems by introducing an explicit
intermediate structure that groups all revocation information for one
issuer. The issuer is identified directly in the issuer field of the
Liao, et al. Expires 7 January 2027 [Page 12]
Internet-Draft C509 Revocation July 2026
structure rather than being inferred from the position of a CRL entry
extension. This makes the grouping unambiguous and easy to parse,
and it allows an issuer to appear in the list even when it has no
revoked certificates.
A second design problem in X.509 CRLs is that each revocation entry
has variable length: the serial number length differs between
certificates, the revocation date uses different encodings depending
on whether the date falls before or after 2050, and optional per-
entry extensions (e.g., reason code) may or may not be present. This
variable-length layout makes it impossible to determine whether a
given serial number is present in the list without scanning every
entry sequentially, resulting in O(n) lookup time. In this document,
the revokedCertsControl structure introduces fixed parameters
(serialNumberLength, dateLength) that make every entry within
revokedCerts exactly of the same size. The flags field can
additionally indicate that entries are sorted in ascending order by
serial number, enabling binary search and reducing lookup time to
O(log(n)). Using a compact byte-string concatenation rather than a
CBOR array of structured items further reduces encoded size and
accelerates parsing. Furthermore, certificates removed from the CRL
(delta CRL removeFromCRL entries in X.509) are kept in a dedicated
removedFromCRLCerts field rather than mixed into revokedCerts. This
keeps revokedCerts free of removal noise, reducing its size and
allowing implementations to process currently-revoked and removed
entries independently.
5.3.9.2. Fields
The revokedCertsList field is either a CBOR array of one or more
PerIssuerRevokedCerts entries, each describing the revocation state
for certificates issued by one issuer, or CBOR null.
revokedCertsList MUST be encoded as CBOR null when all of the
following conditions hold: no certificates are currently revoked, no
certificates have been removed from the CRL, the only issuer that
would appear is the CRL's own authoritySubject (i.e., the issuer
field is null), and there are no non-empty per-issuer extensions.
Each PerIssuerRevokedCerts entry describes revoked certificates for
one issuer using the following fields:
Liao, et al. Expires 7 January 2027 [Page 13]
Internet-Draft C509 Revocation July 2026
* The issuer field identifies the issuer of the certificates covered
by this PerIssuerRevokedCerts entry. When the issuer is a C509
CA, it is encoded as a Name value identical to the issuer field of
the covered C509 certificates. When the issuer is an X.509 CA, it
is encoded as #6.121(bytes) (tag 121 is alternative 0), where the
byte string contains the DER-encoded Name from the issuer field of
the covered X.509 certificates ([X.690]). If the issuer is
identical to the CRL's authoritySubject field, it MUST be encoded
as CBOR null.
* The revokedCertsControl field defines the controls for
interpreting removedFromCRLCerts and revokedCerts. If either
removedFromCRLCerts or revokedCerts is non-null,
revokedCertsControl MUST NOT be null. If both removedFromCRLCerts
and revokedCerts are null, revokedCertsControl MUST be null to
reduce CRL size.
- The flags field is an unsigned integer encoding boolean control
bits for crlType = 0: bit 0 (value 0x01) indicates whether
entries in revokedCerts are sorted in ascending order by the
integer value of the certificate serial number; bit 1 (value
0x02) indicates whether each entry contains a reason code.
Bits greater than 1 are reserved for crlType = 0 and MUST be
zero and MUST be ignored by receivers. Future crlType values
defined in successor documents may assign additional bit
meanings.
- The serialNumberLength field defines the length, in bytes, of a
certificate serial number. It MUST be greater than 0. It
SHOULD be the smallest value that can encode all certificate
serial numbers without leading zeros.
Each certificate serial number is encoded as a fixed-length big-
endian integer of length serialNumberLength. If the encoded value
is shorter than serialNumberLength, it is left-padded with zeros.
- The dateLength field defines the length, in bytes, of the big-
endian encoded revocation-date offset relative to baseDate. A
value of 0 means that no revocation date is included in
revokedCerts entries. This is permitted in C509-native
deployments where the revocation date is not required -- for
example, when minimizing revocation data is more important than
recording the revocation time. Implementations that need to
convert a C509 CRL to an RFC 5280 DER-encoded CRL MUST set
dateLength to a non-zero value, since [RFC5280], Section 5.1
requires a revocationDate in every CRL entry. When dateLength
is non-zero, the offset MUST fit within the specified byte
length without leading zero bytes.
Liao, et al. Expires 7 January 2027 [Page 14]
Internet-Draft C509 Revocation July 2026
- The baseDate field is a reference time used to compute
revocation and removal dates, encoded as described in
Section 4. It MUST be greater than or equal to the issuer
certificate's notBefore, which ensures that all stored offsets
are non-negative. It is RECOMMENDED to set baseDate to the
earliest revocation date or removal-from-CRL date among all
entries in this CRL, as this minimizes the magnitude of stored
offsets and reduces encoding size. Any time between the issuer
certificate's notBefore (inclusive) and that earliest date
(inclusive) is a conformant value. Revocation dates in
revokedCerts and removal dates in removedFromCRLCerts are
stored as non-negative offsets, in seconds, from baseDate.
* The extensions field contains per-issuer extensions. Only the
(extensionID: int, extensionValue: Defined) choice is permitted.
If no per-issuer extensions are present, this field MUST be
encoded as an empty CBOR array.
* The revokedCerts field is a CBOR byte string containing the
concatenated byte sequence of revoked-certificate entries. Each
entry is the concatenation of:
- a big-endian encoded certificate serial number of length
serialNumberLength;
- a big-endian encoded revocation-date offset from baseDate, in
seconds, of length dateLength (absent when dateLength is 0);
and
- an optional reason code (1 byte if bit 1 of flags is set,
absent otherwise).
If there are no entries, this field MUST be encoded as CBOR null
instead of a zero-length byte string.
The revocation date for a given entry is recovered by adding the
stored offset to baseDate. When dateLength is 0, no revocation
date is stored and no date recovery is possible.
Revoked-certificate entries have fixed length. If bit 0 of flags
is set, entries are sorted in ascending order, enabling binary
search for a given serial number in O(log(n)) time.
* The removedFromCRLCerts field contains a concatenated byte
sequence of entries for certificates removed from the CRL since
publication of the CRL with crlNumber = baseCrlNumber. Each entry
is the concatenation of:
Liao, et al. Expires 7 January 2027 [Page 15]
Internet-Draft C509 Revocation July 2026
- a big-endian encoded certificate serial number of length
serialNumberLength; and
- a big-endian encoded removal-date offset from baseDate, in
seconds, of length dateLength (absent when dateLength is 0).
If there are no entries, this field MUST be encoded as CBOR null
instead of a zero-length byte string.
The removal date for a given entry is recovered by adding the
stored offset to baseDate. When dateLength is 0, no removal date
is stored and no date recovery is possible.
Removed-certificate entries have fixed length. If bit 0 of flags
is set, entries are sorted in ascending order, enabling binary
search for a given serial number in O(log(n)) time.
5.3.10. CRL Extensions
The crlExtensions field contains extensions for the CRL. Only the
(extensionID: int, extensionValue: Defined) choice is permitted.
This document does not define any new CRL-level extensions.
Table 2 lists X.509 CRL extensions and their equivalents.
+====+==========================+==========+======================+
|Code| Extension |Reference |Equivalent |
+====+==========================+==========+======================+
|- | authorityKeyIdentifier |[RFC5280],|field |
| | |Section |authorityKeyIdentifier|
| | |5.2.1 | |
+----+--------------------------+----------+----------------------+
|- | issuerAltName |[RFC5280],|- |
| | |Section | |
| | |5.2.2 | |
+----+--------------------------+----------+----------------------+
|- | cRLNumber |[RFC5280],|field crlNumber |
| | |Section | |
| | |5.2.3 | |
+----+--------------------------+----------+----------------------+
|- | deltaCRLIndicator |[RFC5280],|field baseCrlNumber |
| | |Section | |
| | |5.2.4 | |
+----+--------------------------+----------+----------------------+
|- | issuingDistributionPoint |[RFC5280],|- |
| | |Section | |
| | |5.2.5 | |
+----+--------------------------+----------+----------------------+
Liao, et al. Expires 7 January 2027 [Page 16]
Internet-Draft C509 Revocation July 2026
|- | freshestCRL |[RFC5280],|- |
| | |Section | |
| | |5.2.6 | |
+----+--------------------------+----------+----------------------+
|- | authorityInfoAccess |[RFC5280],|- |
| | |Section | |
| | |5.2.7 | |
+----+--------------------------+----------+----------------------+
|- | orderedList |OID |field sorted |
| | |2.5.29.56 |(ascSerialNum); - |
| | |(ITU-T |(ascRevDate) |
| | |X.509, | |
| | |Section | |
| | |9.5.2.5) | |
+----+--------------------------+----------+----------------------+
|- | toBeRevoked |OID |- |
| | |2.5.29.58 | |
| | |(ITU-T | |
| | |X.509, | |
| | |Section | |
| | |9.5.2.6) | |
+----+--------------------------+----------+----------------------+
|- | revokedGroups |OID |- |
| | |2.5.29.59 | |
| | |(ITU-T | |
| | |X.509, | |
| | |Section | |
| | |9.5.2.7) | |
+----+--------------------------+----------+----------------------+
Table 2: CRL extensions and their equivalents
5.3.11. Per-Issuer Extensions
The extensions field of PerIssuerRevokedCerts contains per-issuer
extensions. Only the (extensionID: int, extensionValue: Defined)
choice is permitted. This document defines one per-issuer extension
(expiredCertsOnCRL, see Section 5.3.11.1).
Table 3 lists per-issuer extensions defined in this document.
Liao, et al. Expires 7 January 2027 [Page 17]
Internet-Draft C509 Revocation July 2026
+======+===================+=========================+============+
| Code | Extension | Reference | Equivalent |
+======+===================+=========================+============+
| TBD4 | expiredCertsOnCRL | OID 2.5.29.60 (ITU-T | - |
| | | X.509, Section 9.5.2.8) | |
+------+-------------------+-------------------------+------------+
Table 3: Per-issuer extensions and their equivalents
5.3.11.1. expiredCertsOnCRL
The expiredCertsOnCRL extension indicates that this CRL includes
revocation information for certificates that have already expired.
The extension value is a time value indicating the earliest
expiration date of certificates included on the CRL; certificates
that expired on or after this date are listed even if they are now
expired.
The extension value MUST be encoded as follows.
ExpiredCertsOnCRL = ~time
The value is encoded as described in Section 4. When this extension
is present, a relying party processing expired certificates (for
example, for audit or archiving purposes) SHOULD use the indicated
date to determine the extent of historical revocation coverage.
5.3.12. CRL Entry Extensions
Table 4 lists X.509 CRL entry extensions. No corresponding extension
is defined in this document.
Liao, et al. Expires 7 January 2027 [Page 18]
Internet-Draft C509 Revocation July 2026
+======+=====================+==============+=======================+
| Code | Extension | Reference | Equivalent |
+======+=====================+==============+=======================+
| - | reasonCode | [RFC5280], | field |
| | | Section | removedFromCRLCerts |
| | | 5.3.1 / | and revokedCerts |
| | | ITU-T | |
| | | X.509, | |
| | | Section | |
| | | 9.6.2.1 | |
+------+---------------------+--------------+-----------------------+
| - | holdInstructionCode | [RFC5280], | - |
| | | Section | |
| | | 5.3.2 / | |
| | | ITU-T | |
| | | X.509, | |
| | | Section | |
| | | 9.6.2.2 | |
+------+---------------------+--------------+-----------------------+
| - | invalidityDate | [RFC5280], | - |
| | | Section | |
| | | 5.3.2 / | |
| | | ITU-T | |
| | | X.509, | |
| | | Section | |
| | | 9.6.2.3 | |
+------+---------------------+--------------+-----------------------+
| - | certificateIssuer | [RFC5280], | field issuer within |
| | | Section | PerIssuerRevokedCerts |
| | | 5.3.3 / | |
| | | ITU-T | |
| | | X.509, | |
| | | Section | |
| | | 9.6.2.4 | |
+------+---------------------+--------------+-----------------------+
Table 4: CRL entry extensions defined for X.509 CRLs
5.3.13. signatureValue
Encoded identically to signatureValue in C509 certificates (see
[I-D.ietf-cose-cbor-encoded-cert], Section 3.1.12).
6. C509 OCSP
Liao, et al. Expires 7 January 2027 [Page 19]
Internet-Draft C509 Revocation July 2026
6.1. Overview
C509 OCSP defines CBOR encodings for OCSP requests and OCSP responses
as defined in [RFC6960]. The encoding follows the same compression
principles as C509 CRL and C509 certificates.
C509 OCSP requests and responses are not wire-format-compatible with
DER-encoded OCSP messages as defined in [RFC6960]. The two formats
cannot be mechanically converted to or from each other without
semantic interpretation of the contained data.
C509OCSPRequest and C509OCSPResponse are designed to be extensible.
The first field of every message is ocspRequestType or
ocspResponseType, an unsigned integer that identifies the structure
type. This document defines types 0, 1, and 2. Future
specifications may define additional types by assigning new integer
values, enabling new request or response structures to be introduced
without modifying the existing types.
6.2. Identification of Certificates
To reduce OCSP message size, this document defines two truncated-hash
identifier types used to refer to certificates compactly:
* HashId8 — the leading 8 bytes of the hash value computed using the
enclosing hashAlgorithm. HashId8 is used to identify issuer
certificates and the certificates of OCSP requestors and
responders in request and response structures where a short
identifier provides sufficient uniqueness in the deployment
context.
* HashId20 — the leading 20 bytes of the hash value computed using
the enclosing hashAlgorithm. HashId20 is intended for identifying
certificate serial numbers (the serialNumberHash field) when
higher uniqueness is required to minimize collision risk. When
derived from a secure hash (e.g., SHA-256 or SHA-3-256) and
treated as a random output, it gives ~2^160 preimage work and
~2^80 collision resistance (birthday bound) for the truncated
value. Since the relying party verifies a certificate's signature
before querying OCSP, an adversary needs to construct a different
certificate that (a) validates under the same issuer chain and (b)
has a serial number whose hash truncation equals an existing
certificate's HashId20. Such a construction is practically
infeasible.
HashId8 = bytes .size 8
HashId20 = bytes .size 20
Liao, et al. Expires 7 January 2027 [Page 20]
Internet-Draft C509 Revocation July 2026
6.3. C509 OCSP Request
6.3.1. CDDL
C509OCSPRequest = C509UnsignedOCSPRequest /
C509SignedOCSPRequest /
C509SimpleOCSPRequest
C509UnsignedOCSPRequest = [
ocspRequestType : 0,
hashAlgorithm : IntAlgorithmIdentifier,
nonce : bytes / null,
extensions : Extensions,
requests : PerIssuerOCSPRequests
]
TBSOCSPRequest = (
ocspRequestType : 1,
signatureAlgorithm : IntAlgorithmIdentifier,
hashAlgorithm : IntAlgorithmIdentifier,
nonce : bytes / null,
requestorCertHash : HashId8,
extensions : Extensions,
requests : PerIssuerOCSPRequests,
requestorCerts : COSE_C509 / #6.121(COSE_X509) / null,
)
C509SignedOCSPRequest = [
TBSOCSPRequest,
signatureValue : any,
]
C509SimpleOCSPRequest = [
ocspRequestType : 2,
hashAlgorithm : IntAlgorithmIdentifier,
nonce : bytes / null,
issuerCertHash : HashId8,
serialNumberHash : HashId20,
extensions : Extensions
]
PerIssuerOCSPRequests = [ + PerIssuerOCSPRequest ]
PerIssuerOCSPRequest = (
issuerCertHash : HashId8,
extensions : Extensions,
singleRequests : SingleCertRequests,
)
Liao, et al. Expires 7 January 2027 [Page 21]
Internet-Draft C509 Revocation July 2026
SingleCertRequests = [ + SingleCertRequest ]
SingleCertRequest = (
serialNumberHash : HashId20,
extensions : Extensions,
)
Figure 2: CDDL for C509OCSPRequest
6.3.2. Field Encodings
6.3.2.1. ocspRequestType
The ocspRequestType field serves as the discriminator for
C509OCSPRequest:
+=======+=========================+
| Value | Type |
+=======+=========================+
| 0 | C509UnsignedOCSPRequest |
+-------+-------------------------+
| 1 | C509SignedOCSPRequest |
+-------+-------------------------+
| 2 | C509SimpleOCSPRequest |
+-------+-------------------------+
Table 5
6.3.2.2. issuerCertHash
The issuerCertHash field appears in PerIssuerOCSPRequest,
PerIssuerOCSPResponse, C509SimpleOCSPRequest, and
TBSSimpleOCSPResponse. It contains a hash of the issuer certificate:
* issuerCertHash: hash computed over the CBOR-encoded issuer C509
certificate, or over the DER-encoded issuer X.509 certificate
([X.690]). The hash algorithm is specified by the hashAlgorithm
field of the enclosing request or response structure.
Liao, et al. Expires 7 January 2027 [Page 22]
Internet-Draft C509 Revocation July 2026
In X.509 OCSP ([RFC6960], Section 4.1.1), the CertID structure
identifies the issuer using two separate hashes: issuerNameHash (a
hash of the DER-encoded issuer name) and issuerKeyHash (a hash of the
issuer's public key bit string). This two-hash approach was designed
for interoperability with DER-encoded X.509 structures, but it
doubles the per-issuer overhead in the message. In C509 OCSP, the
issuer is identified by a single hash of the issuer certificate
(issuerCertHash), which is simpler, smaller, and unambiguous.
Implementations that need to cross-reference a C509 issuerCertHash
with an RFC 6960 DER-encoded CertID must recompute the respective
hash inputs; the values are not directly comparable.
6.3.2.3. PerIssuerOCSPRequests, PerIssuerOCSPRequest,
SingleCertRequests and SingleCertRequest
PerIssuerOCSPRequests is a list of PerIssuerOCSPRequest entries. In
X.509 OCSP ([RFC6960], Section 4.1.1), every Request entry embeds a
full CertID containing the issuer identity fields (hashAlgorithm,
issuerNameHash, issuerKeyHash) alongside the serialNumber. When
multiple certificates from the same issuer are queried in a single
request, these issuer fields are repeated verbatim for every entry,
wasting space. PerIssuerOCSPRequest solves this by grouping all
single-certificate requests for the same issuer under one entry: the
issuerCertHash field is encoded once and shared across all
SingleCertRequest entries in the singleRequests list, eliminating the
per-entry duplication.
* The extensions field contains per-issuer extensions that apply to
all single-certificate requests in this PerIssuerOCSPRequest
entry; see Section 6.4.2.12. If no per-issuer extensions are
present, this field MUST be encoded as an empty CBOR array.
* The singleRequests field is a list of SingleCertRequest entries
for certificates from this issuer.
Each SingleCertRequest contains:
* The serialNumberHash field is the truncated hash of the
certificate serial number of the target certificate, computed
using the hashAlgorithm of the enclosing request structure. The
serial number is encoded in big-endian byte order without a
leading zero byte (as in C509 certificates) before hashing. Using
a hash rather than the plain serial number preserves the privacy
of the requestor: an observer cannot determine which certificate
is being queried without already knowing the serial number.
* The extensions field contains extensions for the single request;
see Section 6.4.2.13.
Liao, et al. Expires 7 January 2027 [Page 23]
Internet-Draft C509 Revocation July 2026
6.3.2.4. C509UnsignedOCSPRequest
* The ocspRequestType field MUST be 0, which discriminates
C509UnsignedOCSPRequest from C509SignedOCSPRequest.
* The hashAlgorithm field specifies the hash algorithm used to
compute issuerCertHash and serialNumberHash. The algorithm is
encoded as an integer from the "C509 Hash Algorithms" registry
defined in Section 7.
* The nonce field contains the request nonce, or MUST be null when
no nonce is present.
* The extensions field contains request-level extensions; see
Section 6.4.2.13.
* The requests field is a list of PerIssuerOCSPRequest entries, each
grouping target certificates by issuer; see Section 6.3.2.3.
6.3.2.5. C509SignedOCSPRequest
* The ocspRequestType field MUST be 1, which discriminates
C509SignedOCSPRequest from C509UnsignedOCSPRequest.
* The signatureAlgorithm field specifies the signature algorithm, as
defined in [I-D.ietf-cose-cbor-encoded-cert], Section 3.1.11.
* The hashAlgorithm field specifies the hash algorithm used to
compute requestorCertHash, issuerCertHash, and serialNumberHash.
The algorithm is encoded as an integer from the "C509 Hash
Algorithms" registry defined in Section 7.
* The nonce field is as defined for C509UnsignedOCSPRequest
(Section 6.3.2.4).
* The requestorCertHash field is a hash of the signer's certificate,
computed using hashAlgorithm. requestorCerts MUST carry the
corresponding certificate chain so that the receiver can verify
the identity of the requestor.
* The extensions field contains request-level extensions; see
Section 6.4.2.13.
* The requests field is as defined for C509UnsignedOCSPRequest
(Section 6.3.2.4).
Liao, et al. Expires 7 January 2027 [Page 24]
Internet-Draft C509 Revocation July 2026
* The requestorCerts field contains a sorted certificate chain
starting with the signer's certificate, or MUST be null if no
certificates are transported. When the signer holds a C509
certificate chain, the value is COSE_C509. When the signer holds
an X.509 certificate chain, the value is #6.121(COSE_X509),
wrapping a COSE_X509 chain with CBOR tag 121 (alternative 0).
* The signatureValue field is the signature computed over the CBOR
Sequence of the TBSOCSPRequest group.
6.3.2.6. C509SimpleOCSPRequest
C509SimpleOCSPRequest is a compact request format for querying the
status of a single certificate. Unlike C509UnsignedOCSPRequest,
which uses a two-level PerIssuerOCSPRequests / SingleCertRequest
grouping to batch multiple serial numbers across one or more issuers,
C509SimpleOCSPRequest flattens the structure into a single CBOR array
for the common case of a one-certificate query.
* The ocspRequestType field MUST be 2, which discriminates
C509SimpleOCSPRequest from C509UnsignedOCSPRequest and
C509SignedOCSPRequest.
* The nonce field contains the request nonce, or MUST be null when
no nonce is present.
* The issuerCertHash field identifies the issuer of the target
certificate; see Section 6.3.2.2.
* The serialNumberHash field is the hash of the certificate serial
number of the target certificate, computed using the hashAlgorithm
from C509SimpleOCSPRequest. The serial number is encoded in big-
endian byte order without a leading zero byte before hashing.
Using a hash rather than the plain serial number preserves the
privacy of the requestor: an observer cannot determine which
certificate is being queried without already knowing the serial
number.
* The extensions field contains request-level extensions; see
Section 6.4.2.13. If no extensions are present, this field MUST
be encoded as an empty CBOR array.
6.4. C509 OCSP Response
6.4.1. CDDL
Liao, et al. Expires 7 January 2027 [Page 25]
Internet-Draft C509 Revocation July 2026
C509OCSPResponse = C509ErrorOCSPResponse /
C509BasicOCSPResponse /
C509SimpleOCSPResponse
C509ErrorOCSPResponse = [
ocspResponseType : 0,
responseStatus : int
]
TBSBasicOCSPResponse = (
ocspResponseType : 1,
signatureAlgorithm : IntAlgorithmIdentifier,
hashAlgorithm : IntAlgorithmIdentifier,
nonce : bytes / null,
responderCertHash : HashId8,
producedAt : ~time,
extensions : Extensions,
responses : PerIssuerOCSPResponses,
responderCerts : COSE_C509 / #6.121(COSE_X509) / null,
)
C509BasicOCSPResponse = [
TBSBasicOCSPResponse,
signatureValue : any
]
TBSSimpleOCSPResponse = (
ocspResponseType : 2,
signatureAlgorithm : IntAlgorithmIdentifier,
hashAlgorithm : IntAlgorithmIdentifier,
nonce : bytes / null,
responderCertHash : HashId8,
issuerCertHash : HashId8,
serialNumberHash : HashId20,
certStatus : CertStatus,
producedAt : ~time,
thisUpdate : nint / 0,
nextUpdate : uint / null,
extensions : Extensions,
responderCerts : COSE_C509 / #6.121(COSE_X509) / null,
)
C509SimpleOCSPResponse = [
TBSSimpleOCSPResponse,
signatureValue : any
]
PerIssuerOCSPResponses = [ + PerIssuerOCSPResponse ]
Liao, et al. Expires 7 January 2027 [Page 26]
Internet-Draft C509 Revocation July 2026
PerIssuerOCSPResponse = (
issuerCertHash : HashId8,
extensions : Extensions,
singleResponses : SingleCertResponses,
)
SingleCertResponses = [ + SingleCertResponse ]
SingleCertResponse = (
serialNumberHash : HashId20,
certStatus : CertStatus,
thisUpdate : nint / 0,
nextUpdate : uint / null,
extensions : Extensions,
)
CertStatus = 0 ; good
/ 1 ; not-issued (issuer recognized,
; serial number not issued)
/ 2 ; unknown (issuer not recognized)
/ RevokedInfo
RevokedInfo = [
revocationTime : ~time,
revocationReason : int,
]
Figure 3: CDDL for C509OCSPResponse
6.4.2. Field Encodings
6.4.2.1. C509ErrorOCSPResponse
If the OCSP server cannot process the OCSP query, it returns a
C509ErrorOCSPResponse. The ocspResponseType value MUST be 0, and
responseStatus has the following enumerated values:
Liao, et al. Expires 7 January 2027 [Page 27]
Internet-Draft C509 Revocation July 2026
+=====+==================+
| int | responseStatus |
+=====+==================+
| - | successful |
+-----+------------------+
| 1 | malformedRequest |
+-----+------------------+
| 2 | internalError |
+-----+------------------+
| 3 | tryLater |
+-----+------------------+
| 5 | sigRequired |
+-----+------------------+
| 6 | unauthorized |
+-----+------------------+
Table 6:
responseStatus values
6.4.2.2. C509BasicOCSPResponse
The ocspResponseType field of C509BasicOCSPResponse is 1,
distinguishing it from C509ErrorOCSPResponse. It corresponds to
BasicOCSPResponse in [RFC6960].
TBSBasicOCSPResponse is the group of fields to be signed. The
signatureValue field is the only field outside the signed group.
Covering signatureAlgorithm and responderCerts within the signed
content prevents algorithm-substitution and certificate-chain
substitution attacks; this design goes beyond the protections offered
by the DER-encoded BasicOCSPResponse defined in [RFC6960].
6.4.2.3. C509SimpleOCSPResponse
C509SimpleOCSPResponse is a compact signed response for a single-
certificate status query. It is the response counterpart to
C509SimpleOCSPRequest (see Section 6.3.2.6). Unlike
C509BasicOCSPResponse, which uses a two-level PerIssuerOCSPResponses
/ SingleCertResponse grouping to carry status for multiple
certificates across one or more issuers, C509SimpleOCSPResponse
flattens the structure into a single signed CBOR array for the common
case of a one-certificate response.
TBSSimpleOCSPResponse is the group of fields to be signed. The
signatureValue field is the only field outside the signed group.
Covering signatureAlgorithm, responderCertHash, and responderCerts
within the signed content prevents algorithm-substitution and
certificate-chain substitution attacks.
Liao, et al. Expires 7 January 2027 [Page 28]
Internet-Draft C509 Revocation July 2026
* The ocspResponseType field MUST be 2, which discriminates
C509SimpleOCSPResponse from C509ErrorOCSPResponse and
C509BasicOCSPResponse.
* The signatureAlgorithm field specifies the signature algorithm, as
defined in [I-D.ietf-cose-cbor-encoded-cert], Section 3.1.11. It
is part of TBSSimpleOCSPResponse and is therefore covered by the
signature.
* The hashAlgorithm field specifies the hash algorithm used to
compute responderCertHash, issuerCertHash, and serialNumberHash.
The algorithm is encoded as an integer from the "C509 Hash
Algorithms" registry defined in Section 7.
* The responderCertHash field identifies the OCSP responder; see
Section 6.4.2.5.
* The nonce field contains the request nonce, or MUST be null when
no nonce is present. If present, it MUST have the same value as
the nonce in the corresponding C509SimpleOCSPRequest.
* The issuerCertHash field identifies the issuer of the queried
certificate; see Section 6.3.2.2.
* The serialNumberHash field is the hash of the certificate serial
number of the queried certificate, computed using hashAlgorithm.
The serial number is encoded in big-endian byte order without a
leading zero byte before hashing; see Section 6.4.2.11.1.
* The producedAt field is the time at which this response was
produced, encoded as described in Section 4.
* The thisUpdate field is encoded as a non-positive integer (nint /
0) representing the number of seconds from producedAt at which the
indicated status is known to be correct. It MUST be 0 or
negative, since the status cannot be known at a time in the future
relative to the time the response was produced.
* The nextUpdate field is encoded as a uint representing the number
of seconds from producedAt until the next response update is
expected, or null if the update time is unknown.
* The certStatus field encodes the revocation status; see
Section 6.4.2.11.
* The extensions field contains response-level extensions; see
Section 6.4.2.13. If no extensions are present, this field MUST
be encoded as an empty CBOR array.
Liao, et al. Expires 7 January 2027 [Page 29]
Internet-Draft C509 Revocation July 2026
* The responderCerts field carries the certificate chain starting
with the responder certificate identified by responderCertHash;
see Section 6.4.2.6.
* The signatureValue field is the signature computed over the CBOR
Sequence of the TBSSimpleOCSPResponse group.
6.4.2.4. nonce
If present, this field MUST have the same value as the nonce in the
corresponding request.
6.4.2.5. responderCertHash
responderCertHash is a truncated hash over the responder's
certificate, computed using the same hashAlgorithm as issuerCertHash.
In X.509 OCSP ([RFC6960]), the responder is identified by a
ResponderID CHOICE that carries either a distinguished name or a
public-key hash. C509 OCSP replaces this with a single hash over the
entire responder certificate, which is consistent with the
issuerCertHash design for issuer identification.
6.4.2.6. responderCerts
When present, the responderCerts field carries the certificate chain
starting with the responder certificate identified by
responderCertHash. When the responder holds a C509 certificate
chain, the value is COSE_C509. When the responder holds an X.509
certificate chain, the value is #6.121(COSE_X509), wrapping a
COSE_X509 chain with CBOR tag 121 (alternative 0). The field is part
of TBSBasicOCSPResponse and is therefore covered by the signature,
which prevents certificate-chain substitution attacks.
6.4.2.7. signatureAlgorithm and signatureValue
* signatureAlgorithm: the signature algorithm used to compute
signatureValue, as defined in [I-D.ietf-cose-cbor-encoded-cert],
Section 3.1.11. It is part of the TBSBasicOCSPResponse group and
is therefore covered by the signature.
* signatureValue: the signature computed over the CBOR Sequence of
the TBSBasicOCSPResponse group.
Liao, et al. Expires 7 January 2027 [Page 30]
Internet-Draft C509 Revocation July 2026
6.4.2.8. producedAt, thisUpdate, nextUpdate
The producedAt field is encoded as described in Section 4. The
thisUpdate field is encoded as a non-positive integer (nint / 0)
representing the number of seconds from producedAt at which the
indicated status is known to be correct; it MUST be 0 or negative,
since the status cannot be known at a time in the future relative to
when the response was produced. The nextUpdate field is encoded as a
uint representing the number of seconds from producedAt until the
next update is expected to be available. nextUpdate may be null,
which indicates an unknown update time.
6.4.2.9. extensions
See Section 6.4.2.13.
6.4.2.10. PerIssuerOCSPResponses and PerIssuerOCSPResponse
PerIssuerOCSPResponses is a list of PerIssuerOCSPResponse entries.
For the same reason as on the request side (see Section 6.3.2.3), the
issuerCertHash field is encoded once per issuer and shared across all
SingleCertResponse entries in the singleResponses list, avoiding the
per-entry repetition that would occur if the issuer identity were
embedded in every individual response entry. PerIssuerOCSPResponse
groups single responses for certificates issued by the same issuer;
the issuer is identified by issuerCertHash (see Section 6.3.2.2).
* The extensions field contains per-issuer extensions that apply to
all single-certificate responses in this PerIssuerOCSPResponse
entry; see Section 6.4.2.12. If no per-issuer extensions are
present, this field MUST be encoded as an empty CBOR array.
* The singleResponses field contains one SingleCertResponse for each
queried certificate issued by that issuer.
6.4.2.11. SingleCertResponse
6.4.2.11.1. serialNumberHash
This field contains the truncated hash of the serial number of the
certificate being queried. It is computed using the hashAlgorithm
from the enclosing TBSBasicOCSPResponse and contains the first 20
bytes. The serial number is encoded in big-endian byte order without
a leading zero byte before hashing. In X.509, a
CertificateSerialNumber INTEGER is DER-encoded with a leading zero
byte when the most-significant bit is set; that leading zero MUST be
stripped before computing the hash. In X.509 OCSP ([RFC6960],
Section 4.1.1), the CertID structure carries the plain serialNumber
Liao, et al. Expires 7 January 2027 [Page 31]
Internet-Draft C509 Revocation July 2026
directly. C509 OCSP replaces this with a hash to preserve privacy:
an observer cannot determine which certificate was queried without
already knowing the serial number.
6.4.2.11.2. extensions
See Section 6.4.2.13.
6.4.2.11.3. certStatus
CertStatus is encoded either as an integer (for good, not-issued, and
unknown) or as a RevokedInfo array:
* 0: good -- the certificate is not revoked.
* 1: not-issued -- the issuer is recognized but the serial number is
unknown.
* 2: unknown -- the responder does not recognize the issuer
identified by issuerCertHash.
* RevokedInfo: revoked -- a fixed-length 2-element array carrying
revocationTime and revocationReason. The revocationReason field
is encoded as specified in Section 5.3.8. When the revocation
reason is not known, revocationReason MUST be set to 0
(unspecified).
The integer values are chosen to align with the ASN.1 IMPLICIT tag
numbers of CertStatus in [RFC6960]: good uses [0] (value 0) and
unknown uses [2] (value 2). The ASN.1 revoked alternative uses [1];
since C509 represents the revoked status as the explicit RevokedInfo
array, the integer value 1 becomes available. It is assigned to the
not-issued status, which was introduced in [RFC6960], Section 4.4.8
to distinguish unrecognized serial numbers from unrecognized issuers,
thereby maintaining a contiguous integer range for the non-revoked
statuses.
6.4.2.12. Per-Issuer OCSP Extensions
PerIssuerOCSPRequest.extensions and PerIssuerOCSPResponse.extensions
carry per-issuer extensions. Only the (extensionID: int,
extensionValue: Defined) choice of Extensions is permitted. If no
per-issuer extensions are present, the field MUST be encoded as an
empty CBOR array [].
Table 7 lists the per-issuer extensions defined in this document.
Liao, et al. Expires 7 January 2027 [Page 32]
Internet-Draft C509 Revocation July 2026
+================+===========+============+==========+
| Code | Extension | Applied in | Comments |
+================+===========+============+==========+
| (none defined) | | | |
+----------------+-----------+------------+----------+
Table 7: Per-issuer OCSP extensions
6.4.2.13. OCSP Extensions
Table 8 describes the OCSP extensions defined in [RFC6960] and their
mapping in this document.
Liao, et al. Expires 7 January 2027 [Page 33]
Internet-Draft C509 Revocation July 2026
+====+==========+=================================+==========+============+
|Code|Extension |RFC Reference |Applied in|Replaced in |
| | | | |this |
| | | | |document |
+====+==========+=================================+==========+============+
| - |nonce |[RFC6960], Section 4.4.1 |Request |field nonce |
| | | |Extension,| |
| | | |Response | |
| | | |Extension | |
+----+----------+---------------------------------+----------+------------+
| - |CRL |[RFC6960], Section 4.4.2 |Single |- |
| |References| |Response | |
| | | |Extension | |
+----+----------+---------------------------------+----------+------------+
|TBD2|Acceptable|[RFC6960], Section 4.4.3 |Request |- |
| |Response | |Extension | |
| |Types | | | |
+----+----------+---------------------------------+----------+------------+
| - |Archive |[RFC6960], Section 4.4.4 |Response |- |
| |Cutoff | |Extension | |
+----+----------+---------------------------------+----------+------------+
| - |Service |[RFC6960], Section 4.4.5 |Request |- |
| |Locator | |Extension | |
+----+----------+---------------------------------+----------+------------+
|TBD3|Preferred |[RFC6960], Section 4.4.7 |Request |- |
| |Signature | |Extension | |
| |Algorithms| | | |
+----+----------+---------------------------------+----------+------------+
| - |Extended |[RFC6960], Section 4.4.8 |Response |cert status |
| |Revoked | |Extension |not-issued |
| |Definition| | |(for serial |
| | | | |numbers not |
| | | | |issued by a |
| | | | |recognized |
| | | | |issuer) and |
| | | | |unknown (for|
| | | | |unrecognized|
| | | | |issuers) |
+----+----------+---------------------------------+----------+------------+
|TBD6|TN Query |[I-D.ietf-stir-certificates-ocsp]|Single |- |
| | | |Request | |
| | | |Extension | |
+----+----------+---------------------------------+----------+------------+
Table 8: OCSP extensions defined in RFC 6960
This document defines the following extension values:
Liao, et al. Expires 7 January 2027 [Page 34]
Internet-Draft C509 Revocation July 2026
* Acceptable Response Types: The extension value MUST be encoded as
follows.
AcceptableResponseTypes = [ + int]
The integers in AcceptableResponseTypes form a sorted list of
preferred C509OCSPResponse types, in descending order of preference,
that the requestor is willing to accept. This document defines types
0 (C509ErrorOCSPResponse), 1 (C509BasicOCSPResponse), and 2
(C509SimpleOCSPResponse). Type 0 (C509ErrorOCSPResponse) is always
implicitly supported and does not need to be listed. When this
extension is absent, an OCSP server responding to a
C509UnsignedOCSPRequest or C509SignedOCSPRequest MUST reply with a
C509BasicOCSPResponse (type 1); an OCSP server responding to a
C509SimpleOCSPRequest MUST reply with a C509SimpleOCSPResponse (type
2). If AcceptableResponseTypes contains type 2 but not type 1, and
the corresponding request contains entries for two or more
certificates, the server SHALL return a C509ErrorOCSPResponse with
responseStatus set to malformedRequest (1), since
C509SimpleOCSPResponse can only carry status for a single
certificate.
* Preferred Signature Algorithms: The extension value MUST be
encoded as follows.
PreferredSignatureAlgorithm = (
sigIdentifier : IntAlgorithmIdentifier,
pubKeyAlgIdentifiers : [ 2* IntAlgorithmIdentifier ]
/ IntAlgorithmIdentifier
/ null,
)
IntAlgorithmIdentifier = int
PreferredSignatureAlgorithms = [ + PreferredSignatureAlgorithm ]
The sigIdentifier field carries the signature algorithm identifier.
The pubKeyAlgIdentifiers field carries the public key algorithm
identifier and MUST be one of:
* a CBOR array of two or more IntAlgorithmIdentifier values, sorted
in descending order of preference, when the responder is willing
to accept any of the listed public key algorithms as a match for
this signature algorithm preference (e.g., to express hybrid or
multi-algorithm key policies); the first entry in the array
represents the most preferred public key algorithm,
Liao, et al. Expires 7 January 2027 [Page 35]
Internet-Draft C509 Revocation July 2026
* a single IntAlgorithmIdentifier value, when exactly one public key
algorithm is acceptable, or
* null, when the public key algorithm is unconstrained or implied by
sigIdentifier.
PreferredSignatureAlgorithms MUST be sorted in descending order of
preference; the first entry represents the most preferred algorithm
combination.
* TN Query: The extension value MUST be encoded as follows.
TNQuery = text .size (1..15)
The TNQuery extension carries a telephone number string conforming to
the TelephoneNumber ASN.1 type ([RFC8226], Section 3). When included
in single request extensions, it specifies the telephone number for
which the OCSP query is being performed (typically the number from
the "orig" field of a PASSporT being validated).
Clients MUST include this extension in the single-request extensions
per [I-D.ietf-stir-certificates-ocsp].
6.5. Certificate Type Interoperability
C509 OCSP uses a single set of request and response structures that
handles both C509 and X.509 certificates without modification. All
participants -- requestor, responder, and issuer -- are identified by
a hash over their certificate rather than by type-specific fields
such as a Subject distinguished name, SubjectKeyIdentifier, or the
X.509 ResponderID CHOICE (byName or byKey). Because a hash applies
uniformly regardless of the certificate encoding, the same OCSP
structures accommodate C509 certificates (CBOR-encoded), X.509
certificates (DER-encoded), and any future certificate types.
The only per-type differences are in how identity hashes are computed
and how certificate chains are carried:
Liao, et al. Expires 7 January 2027 [Page 36]
Internet-Draft C509 Revocation July 2026
+===================+======================+=====================+
| Field | C509 certificate | X.509 certificate |
+===================+======================+=====================+
| issuerCertHash | Hash of CBOR-encoded | Hash of DER-encoded |
| | C509Certificate | X.509 certificate |
+-------------------+----------------------+---------------------+
| requestorCertHash | Hash of CBOR-encoded | Hash of DER-encoded |
| | C509Certificate | X.509 certificate |
+-------------------+----------------------+---------------------+
| responderCertHash | Hash of CBOR-encoded | Hash of DER-encoded |
| | C509Certificate | X.509 certificate |
+-------------------+----------------------+---------------------+
| requestorCerts / | COSE_C509 | #6.121(COSE_X509) |
| responderCerts | | |
+-------------------+----------------------+---------------------+
Table 9: Per-type differences in C509 OCSP identity fields
In a hybrid deployment where the responder holds an X.509
certificate, responderCertHash contains the hash of the DER-encoded
X.509 certificate and responderCerts carries a #6.121(COSE_X509)
chain. In a deployment using C509 certificates throughout, all
identity hashes are computed over CBOR-encoded certificates and
certificate chains are carried as COSE_C509. The hashAlgorithm field
at the top level of each request or response structure governs all
hashes within that structure.
6.6. OCSP Stapling in TLS
In standard TLS certificate status stapling (see the status_request
extension, [RFC8446], Section 4.4.2.1), the stapled OCSP response is
a DER-encoded OCSPResponse. To allow C509 OCSP stapling, this
document defines a new TLS CertificateStatusType value [RFC6066],
Section 8:
+=======+===========+===============+
| Value | Name | Reference |
+=======+===========+===============+
| TBD1 | c509_ocsp | This document |
+-------+-----------+---------------+
Table 10: TLS
CertificateStatusType for C509
OCSP
When CertificateStatusType is c509_ocsp, the status field contains a
CBOR-encoded C509OCSPResponse instead of a DER-encoded OCSPResponse.
Liao, et al. Expires 7 January 2027 [Page 37]
Internet-Draft C509 Revocation July 2026
7. C509 Hash Algorithms
This document defines the following hash algorithms.
+-------+----------------------------------------------------------+
| Value | Hash Algorithm |
+=======+==========================================================+
| 0 | Name: SHA-256 |
| | Identifiers: id-sha256 |
| | OID: 2.16.840.1.101.3.4.2.1 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 01 |
| | Comments: |
+-------+----------------------------------------------------------+
| 1 | Name: SHA-384 |
| | Identifiers: id-sha384 |
| | OID: 2.16.840.1.101.3.4.2.2 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 02 |
| | Comments: |
+-------+----------------------------------------------------------+
| 2 | Name: SHA-512 |
| | Identifiers: id-sha512 |
| | OID: 2.16.840.1.101.3.4.2.3 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 03 |
| | Comments: |
+-------+----------------------------------------------------------+
| 3 | Name: SHA-224 |
| | Identifiers: id-sha224 |
| | OID: 2.16.840.1.101.3.4.2.4 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 04 |
| | Comments: |
+-------+----------------------------------------------------------+
| 4 | Name: SM3 |
| | Identifiers: id-sm3 |
| | OID: 1.2.156.10197.1.401 |
| | Parameters: absent |
| | DER: 06 08 2A 81 1C 84 8E 35 01 04 01 |
| | Comments: |
+-------+----------------------------------------------------------+
| 5 | Name: SHA3-256 |
| | Identifiers: id-sha3-256 |
| | OID: 2.16.840.1.101.3.4.2.8 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 08 |
| | Comments: |
Liao, et al. Expires 7 January 2027 [Page 38]
Internet-Draft C509 Revocation July 2026
+-------+----------------------------------------------------------+
| 6 | Name: SHA3-384 |
| | Identifiers: id-sha3-384 |
| | OID: 2.16.840.1.101.3.4.2.9 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 09 |
| | Comments: |
+-------+----------------------------------------------------------+
| 7 | Name: SHA3-512 |
| | Identifiers: id-sha3-512 |
| | OID: 2.16.840.1.101.3.4.2.10 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 0A |
| | Comments: |
+-------+----------------------------------------------------------+
| 8 | Name: SHA3-224 |
| | Identifiers: id-sha3-224 |
| | OID: 2.16.840.1.101.3.4.2.7 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 07 |
| | Comments: |
+-------+----------------------------------------------------------+
| 9 | Name: SHAKE128 |
| | Identifiers: id-shake128 |
| | OID: 2.16.840.1.101.3.4.2.11 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 0B |
| | Comments: |
+-------+----------------------------------------------------------+
| 10 | Name: SHAKE256 |
| | Identifiers: id-shake256 |
| | OID: 2.16.840.1.101.3.4.2.12 |
| | Parameters: absent |
| | DER: 60 86 48 01 65 03 04 02 0C |
| | Comments: |
+-------+----------------------------------------------------------+
Figure 4: C509 Hash Algorithms
8. Security Considerations
TODO
9. IANA Considerations
This document has the following actions for IANA.
Liao, et al. Expires 7 January 2027 [Page 39]
Internet-Draft C509 Revocation July 2026
Note to RFC Editor: Please replace all occurrences of "[RFC-XXXX]"
with the RFC number of this specification and delete this paragraph.
9.1. Extension Identifiers Registry
IANA is requested to assign the new values shown in Figure 5 in the
"C509 Extensions" registry under the new registry group "CBOR Encoded
X.509 (C509)" defined in [I-D.ietf-cose-cbor-encoded-cert].
+-------+----------------------------------------------------------+
| Value | Extension |
+=======+==========================================================+
| TBD2 | Name: Acceptable Response Types |
| | Identifiers: id-pkix-ocsp-response |
| | OID: 1.3.6.1.5.5.7.48.1.4 |
| | DER: 06 09 2B 06 01 05 05 07 30 01 04 |
| | Comments: RFC 6960 |
| | extensionValue: AcceptableResponseTypes |
+-------+----------------------------------------------------------+
| TBD3 | Name: Preferred Signature Algorithms |
| | Identifiers: id-pkix-ocsp-pref-sig-algs |
| | OID: 1.3.6.1.5.5.7.48.1.8 |
| | DER: 06 09 2B 06 01 05 05 07 30 01 08 |
| | Comments: RFC 6960 |
| | extensionValue: PreferredSignatureAlgorithms |
+-------+----------------------------------------------------------+
| TBD4 | Name: Expired Certificates on CRL |
| | Identifiers: id-ce-expiredCertsOnCRL |
| | OID: 2.5.29.60 |
| | DER: 06 03 55 1D 3C |
| | Comments: ITU-T X.509, Section 9.5.2.8 |
| | extensionValue: ExpiredCertsOnCRL |
+-------+----------------------------------------------------------+
| TBD6 | Name: TN Query |
| | Identifiers: id-pkix-ocsp-stir-tn |
| | OID: 1.3.6.1.5.5.7.48.1.10 |
| | DER: 06 09 2B 06 01 05 05 07 30 01 0A |
| | Comments: draft-ietf-stir-certificates-ocsp |
| | extensionValue: TNQuery |
+-------+----------------------------------------------------------+
Figure 5: C509 extension identifier allocation requests
9.2. C509 Hash Algorithms Registry
IANA is requested to create a new registry "C509 Hash Algorithms"
under the registry group "CBOR Encoded X.509 (C509)" defined in
[I-D.ietf-cose-cbor-encoded-cert].
Liao, et al. Expires 7 January 2027 [Page 40]
Internet-Draft C509 Revocation July 2026
The registration policy is either "Private Use", "IETF Review with
Expert Review", or "Expert Review" per [RFC8126], Section 4.5.
"Expert Review" guidelines are provided in Section 9.6.
All assignments according to "IETF Review with Expert Review" are
made on an "IETF Review" basis per [RFC8126], Section 4.8, with
Expert Review additionally required per [RFC8126], Section 4.5. The
procedure for early IANA allocation of Standards Track code points
defined in [RFC7120] also applies. When such a procedure is used,
IANA will ask the designated expert(s) to approve the early
allocation before registration. In addition, WG chairs are
encouraged to consult the expert(s) early during the process outlined
in [RFC7120], Section 3.1.
The columns of this registry are:
* Value: This field contains the value used to identify the C509
hash algorithm. These values MUST be unique. The value can be a
positive integer or a negative integer. Different ranges of
values use different registration policies [RFC8126]. Integer
values from -24 to 23 are designated as "IETF Review with Expert
Review". Integer values greater than 32767 are marked as "Private
Use". All other integer values are designated as "Expert Review".
This field MUST NOT be empty.
* Name: This field contains the name of the C509 hash algorithm.
This field MUST NOT be empty.
* Identifiers: This field contains additional identifiers of the
C509 hash algorithm, if any is available.
* OID: This field contains the OID corresponding to the C509 hash
algorithm. This field MUST NOT be empty.
* Parameters: This field contains the parameters of the C509 hash
algorithm. This field MUST NOT be empty. If the C509 hash
algorithm has no parameters, this field contains the string
"absent".
* DER: This field contains the DER encoding of the ASN.1 value of
type DigestInfo for the C509 hash algorithm. This field MUST NOT
be empty.
* Comments: This field contains any optional comment about the C509
hash algorithm.
* Reference: This field contains a pointer to the public
specification for the C509 hash algorithm, if one is available.
Liao, et al. Expires 7 January 2027 [Page 41]
Internet-Draft C509 Revocation July 2026
This registry has been initially populated with the entries defined
in Section 7.
9.3. TLS CertificateStatusType Registry
IANA is requested to assign the value shown in Table 11 in the "TLS
Certificate Status Types" registry under "Transport Layer Security
(TLS) Extensions":
+=======+=============+===============+=========+
| Value | Description | Reference | Comment |
+=======+=============+===============+=========+
| TBD1 | c509_ocsp | This document | N/A |
+-------+-------------+---------------+---------+
Table 11: TLS CertificateStatusType
allocation request
9.4. Media Type Application Registry
IANA is requested to assign the following entries into the
"application" registry in the registry group "Media Types" with this
document as reference.
9.4.1. Media Type application/c509-crl+cbor
When the application/c509-crl+cbor media type is used, the data is a
C509CRL structure.
Subtype name: c509-crl+cbor
Required parameters: N/A
Encoding considerations: binary
Security considerations: See Section 8 of [RFC-XXXX].
Interoperability considerations: N/A
Published specification: [RFC-XXXX]
Applications that use this media type: Any MIME-compliant transport
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
Liao, et al. Expires 7 January 2027 [Page 42]
Internet-Draft C509 Revocation July 2026
* Magic number(s): N/A
* File extension(s): .c509
* Macintosh file type code(s): N/A
Person & email address to contact for further information:
iesg@ietf.org
Intended usage: COMMON
Restrictions on usage: N/A
Author: COSE WG
Change controller: IETF
9.4.2. Media Type application/c509-crlinfo+cbor
When the application/c509-crlinfo+cbor media type is used, the data
is a C509CRLInfo structure.
Subtype name: c509-crlinfo+cbor
Required parameters: N/A
Encoding considerations: binary
Security considerations: See Section 8 of [RFC-XXXX].
Interoperability considerations: N/A
Published specification: [RFC-XXXX]
Applications that use this media type: Any MIME-compliant transport
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): N/A
* File extension(s): .c509
* Macintosh file type code(s): N/A
Liao, et al. Expires 7 January 2027 [Page 43]
Internet-Draft C509 Revocation July 2026
Person & email address to contact for further information:
iesg@ietf.org
Intended usage: COMMON
Restrictions on usage: N/A
Author: COSE WG
Change controller: IETF
9.4.3. Media Type application/c509-ocspreq+cbor
When the application/c509-ocspreq+cbor media type is used, the data
is a C509OCSPRequest structure.
Subtype name: c509-ocspreq+cbor
Required parameters: N/A
Encoding considerations: binary
Security considerations: See Section 8 of [RFC-XXXX].
Interoperability considerations: N/A
Published specification: [RFC-XXXX]
Applications that use this media type: OCSP clients
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): N/A
* File extension(s): .c509
* Macintosh file type code(s): N/A
Person & email address to contact for further information:
iesg@ietf.org
Intended usage: COMMON
Restrictions on usage: N/A
Liao, et al. Expires 7 January 2027 [Page 44]
Internet-Draft C509 Revocation July 2026
Author: COSE WG
Change controller: IETF
9.4.4. Media Type application/c509-ocspresp+cbor
When the application/c509-ocspresp+cbor media type is used, the data
is a C509OCSPResponse structure.
Subtype name: c509-ocspresp+cbor
Required parameters: N/A
Encoding considerations: binary
Security considerations: See Section 8 of [RFC-XXXX].
Interoperability considerations: N/A
Published specification: [RFC-XXXX]
Applications that use this media type: OCSP servers
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): N/A
* File extension(s): .c509
* Macintosh file type code(s): N/A
Person & email address to contact for further information:
iesg@ietf.org
Intended usage: COMMON
Restrictions on usage: N/A
Author: COSE WG
Change controller: IETF
Liao, et al. Expires 7 January 2027 [Page 45]
Internet-Draft C509 Revocation July 2026
9.5. CoAP Content-Formats Registry
IANA is requested to add entries for "application/c509-crl+cbor",
"application/c509-crlinfo+cbor", "application/c509-ocspreq+cbor" and
"application/c509-ocspresp+cbor" to the "CoAP Content-Formats"
registry in the registry group "Constrained RESTful Environments
(CoRE) Parameters".
+-------------------------+---------+-------+------------+
| Content | Content | ID | Reference |
| Type | Coding | | |
+=========================+=========+=======+============+
| application/ | - | TBD7 | [[this |
| c509-crl+cbor | | | document]] |
+-------------------------+---------+-------+------------+
| application/ | | | [[this |
| c509-crlinfo+cbor | - | TBD8 | document]] |
+-------------------------+---------+-------+------------+
| application/ | - | TBD9 | [[this |
| c509-ocspreq+cbor | | | document]] |
+-------------------------+---------+-------+------------+
| application/ | - | TBD10 | [[this |
| c509-ocspresp+cbor | | | document]] |
+-------------------------+---------+-------+------------+
9.6. Expert Review Guidelines
TODO
10. References
10.1. Normative References
[I-D.ietf-cose-cbor-encoded-cert]
Mattsson, J. P., Selander, G., Raza, S., Höglund, J.,
Furuhed, M., and L. Liao, "CBOR Encoded X.509 Certificates
(C509 Certificates)", Work in Progress, Internet-Draft,
draft-ietf-cose-cbor-encoded-cert-20, 30 June 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-cose-
cbor-encoded-cert-20>.
[I-D.ietf-stir-certificates-ocsp]
Peterson, J. and S. Turner, "OCSP Usage for Secure
Telephone Identity Certificates", Work in Progress,
Internet-Draft, draft-ietf-stir-certificates-ocsp-14, 10
June 2026, <https://datatracker.ietf.org/doc/html/draft-
ietf-stir-certificates-ocsp-14>.
Liao, et al. Expires 7 January 2027 [Page 46]
Internet-Draft C509 Revocation July 2026
[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/rfc/rfc2119>.
[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/rfc/rfc5280>.
[RFC6066] Eastlake 3rd, D., "Transport Layer Security (TLS)
Extensions: Extension Definitions", RFC 6066,
DOI 10.17487/RFC6066, January 2011,
<https://www.rfc-editor.org/rfc/rfc6066>.
[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/rfc/rfc6960>.
[RFC7120] Cotton, M., "Early IANA Allocation of Standards Track Code
Points", BCP 100, RFC 7120, DOI 10.17487/RFC7120, January
2014, <https://www.rfc-editor.org/rfc/rfc7120>.
[RFC7925] Tschofenig, H., Ed. and T. Fossati, "Transport Layer
Security (TLS) / Datagram Transport Layer Security (DTLS)
Profiles for the Internet of Things", RFC 7925,
DOI 10.17487/RFC7925, July 2016,
<https://www.rfc-editor.org/rfc/rfc7925>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/rfc/rfc8126>.
[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/rfc/rfc8174>.
[RFC8226] Peterson, J. and S. Turner, "Secure Telephone Identity
Credentials: Certificates", RFC 8226,
DOI 10.17487/RFC8226, February 2018,
<https://www.rfc-editor.org/rfc/rfc8226>.
Liao, et al. Expires 7 January 2027 [Page 47]
Internet-Draft C509 Revocation July 2026
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/rfc/rfc8446>.
[RFC8610] Birkholz, H., Vigano, C., and C. Bormann, "Concise Data
Definition Language (CDDL): A Notational Convention to
Express Concise Binary Object Representation (CBOR) and
JSON Data Structures", RFC 8610, DOI 10.17487/RFC8610,
June 2019, <https://www.rfc-editor.org/rfc/rfc8610>.
[RFC8742] Bormann, C., "Concise Binary Object Representation (CBOR)
Sequences", RFC 8742, DOI 10.17487/RFC8742, February 2020,
<https://www.rfc-editor.org/rfc/rfc8742>.
[RFC8949] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", STD 94, RFC 8949,
DOI 10.17487/RFC8949, December 2020,
<https://www.rfc-editor.org/rfc/rfc8949>.
[RFC9147] Rescorla, E., Tschofenig, H., and N. Modadugu, "The
Datagram Transport Layer Security (DTLS) Protocol Version
1.3", RFC 9147, DOI 10.17487/RFC9147, April 2022,
<https://www.rfc-editor.org/rfc/rfc9147>.
[RFC9360] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Header Parameters for Carrying and Referencing X.509
Certificates", RFC 9360, DOI 10.17487/RFC9360, February
2023, <https://www.rfc-editor.org/rfc/rfc9360>.
[RFC9682] Bormann, C., "Updates to the Concise Data Definition
Language (CDDL) Grammar", RFC 9682, DOI 10.17487/RFC9682,
November 2024, <https://www.rfc-editor.org/rfc/rfc9682>.
10.2. Informative References
[CborMe] Bormann, C., "CBOR Playground", May 2018,
<https://cbor.me/>.
[POSIX] "IEEE Standard for Information Technology--Portable
Operating System Interface (POSIX(TM)) Base
Specifications, Issue 7", January 2018,
<https://pubs.opengroup.org/onlinepubs/9699919799/>.
[RFC7228] Bormann, C., Ersue, M., and A. Keranen, "Terminology for
Constrained-Node Networks", RFC 7228,
DOI 10.17487/RFC7228, May 2014,
<https://www.rfc-editor.org/rfc/rfc7228>.
Liao, et al. Expires 7 January 2027 [Page 48]
Internet-Draft C509 Revocation July 2026
[X.690] "ASN.1 encoding rules: Specification of Basic Encoding
Rules (BER), Canonical Encoding Rules (CER) and
Distinguished Encoding Rules (DER)", n.d.,
<https://www.itu.int/rec/T-REC-X.690>.
Appendix A. Examples
A.1. Overview
+==========+==================+============+============+===========+
| Section | Description | size(C509) | size(X509) | Size |
| | | | | Reduction |
+==========+==================+============+============+===========+
| Appendix | CRL Example | 147 | 120 | 18% |
| A.3.1 | Without Revoked | | | |
| | Certificates | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | CRL Example | 335 | 177 | 47% |
| A.3.2 | With Revoked | | | |
| | Certificates | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Delta CRL | 335 | 160 | 52% |
| A.3.3 | Example With | | | |
| | Revoked | | | |
| | Certificates | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Indirect CRL | 409 | 202 | 51% |
| A.3.4 | Example With | | | |
| | Revoked | | | |
| | Certificates | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Simple OCSP | 152 | 51 | 66% |
| A.4.1 | Request Example | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Unsigned OCSP | 483 | 132 | 73% |
| A.4.2 | Request Example | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Signed OCSP | 592 | 209 | 65% |
| A.4.3 | Request Example | | | |
| | Without | | | |
| | Requestor's | | | |
| | Certificate | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Signed OCSP | 1043 | 420 | 60% |
| A.4.4 | Request Example | | | |
| | With | | | |
| | Requestor's | | | |
| | Certificate | | | |
Liao, et al. Expires 7 January 2027 [Page 49]
Internet-Draft C509 Revocation July 2026
+----------+------------------+------------+------------+-----------+
| Appendix | Signed OCSP | 1379 | 625 | 55% |
| A.4.5 | Request Example | | | |
| | With | | | |
| | Requestor's | | | |
| | Certificate | | | |
| | Chain | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Error OCSP | 5 | 3 | 40% |
| A.5.1 | Response | | | |
| | Example | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Simple OCSP | 338 | 140 | 59% |
| A.5.2 | Response | | | |
| | Example | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Basic OCSP | 845 | 248 | 71% |
| A.5.3 | Response | | | |
| | Example Without | | | |
| | Responder's | | | |
| | Certificate | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Basic OCSP | 1189 | 446 | 62% |
| A.5.4 | Response | | | |
| | Example With | | | |
| | Responder's | | | |
| | Certificate | | | |
+----------+------------------+------------+------------+-----------+
| Appendix | Basic OCSP | 1525 | 651 | 57% |
| A.5.5 | Response | | | |
| | Example With | | | |
| | Responder's | | | |
| | Certificate | | | |
| | Chain | | | |
+----------+------------------+------------+------------+-----------+
Table 12: Size comparison in examples (TODO: update the percent data)
A.2. Helper Keys and Certificates
A.2.1. CA Private Key and Certificate
A.2.1.1. CA Private Key
-----BEGIN PRIVATE KEY-----
MC4CAQAwBQYDK2VwBCIEIDP+AdMbqXudBAN3YNAwoR0i3nl4IuoSSA6Hazy2oAKc
-----END PRIVATE KEY-----
Liao, et al. Expires 7 January 2027 [Page 50]
Internet-Draft C509 Revocation July 2026
A.2.1.2. CA Certificate
A.2.1.2.1. Plain Hex
8B0241010C73746573742063726C6F6373702D726F6F7463611A677485801A6B36EC
7F6F746573742063726C6F6373702D63610C58205EF8A355A001A7C50D2349470120
8131A4BB2AB920D40BFB0EE1F6AB28FF74008801542F45E78D2CAEDF368CDF53C390
05D492450E1056211860230107542DA3A403F7D2F4E0B3D8031A73BA8A839F557F0F
5840E50465D60C02A2111EF3FC6E44F2A36008765B552351F9A3F5B2AA7C76F1F05D
259847A4F4250B2E4B0AE2099762A2596D3CC1DB2CCD180AA0A2D0E191310B0F
A.2.1.2.2. Textual Representation
Certificate
TBSCertificate
Certificate Type: 2
Serial Number
01
Signature Algorithm: Ed25519 (12)
Issuer : CN=test crlocsp-rootca
Subject: CN=test crlocsp-ca
Validity
Not Before: 2025-01-01T00:00:00Z
Not After : 2026-12-31T23:59:59Z
Subject Public Key Info:
algorithm: Ed25519 (12)
Raw public key
5e:f8:a3:55:a0:01:a7:c5:0d:23:49:47:01:20:81:31:
a4:bb:2a:b9:20:d4:0b:fb:0e:e1:f6:ab:28:ff:74:00
Extensions
SubjectKeyIdentifier (1)
2f:45:e7:8d:2c:ae:df:36:8c:df:53:c3:90:05:d4:92:
45:0e:10:56
KeyUsage (2), critical
0x60: [keyCertSign, cRLSign]
BasicConstraints (4), critical
CA: true, pathLenConstraint: 1
AuthorityKeyIdentifier (7)
Key Identifier
2d:a3:a4:03:f7:d2:f4:e0:b3:d8:03:1a:73:ba:8a:83:
9f:55:7f:0f
Signature Value
e5:04:65:d6:0c:02:a2:11:1e:f3:fc:6e:44:f2:a3:60:
08:76:5b:55:23:51:f9:a3:f5:b2:aa:7c:76:f1:f0:5d:
25:98:47:a4:f4:25:0b:2e:4b:0a:e2:09:97:62:a2:59:
6d:3c:c1:db:2c:cd:18:0a:a0:a2:d0:e1:91:31:0b:0f
Liao, et al. Expires 7 January 2027 [Page 51]
Internet-Draft C509 Revocation July 2026
A.2.2. CRL Signer Private Key and Certificate
A.2.2.1. CRL Signer Private Key
-----BEGIN PRIVATE KEY-----
MC4CAQAwBQYDK2VwBCIEIOJ3HnsrBJ5g5Pb5oy7qlvijr3Wfx3ywAUvnmRV4354s
-----END PRIVATE KEY-----
A.2.2.2. CRL Signer Certificate
A.2.2.2.1. Plain Hex
8B024212340C6F746573742063726C6F6373702D63611A6775D7001A69570A806A63
726C2D7369676E65720C5820C9BA1EC496DACB97AED087ADE390F398FBD477871EE9
203817EC0E31902789FF86015409E433582556550A27DB4A19BCE2D660884722B621
184007542F45E78D2CAEDF368CDF53C39005D492450E10565840D46E6A8F9FD53417
F36DFE56CBB8CACE0FC3E59ACBE72CD9916B3E4C5022D06D16CC9BF9AC54394037C9
5433644194FAE18FF783381959584A21BDC0E1C6CB0B
A.2.2.2.2. Textual Representation
Liao, et al. Expires 7 January 2027 [Page 52]
Internet-Draft C509 Revocation July 2026
Certificate
TBSCertificate
Certificate Type: 2
Serial Number
12:34
Signature Algorithm: Ed25519 (12)
Issuer : CN=test crlocsp-ca
Subject: CN=crl-signer
Validity
Not Before: 2025-01-02T00:00:00Z
Not After : 2026-01-02T00:00:00Z
Subject Public Key Info:
algorithm: Ed25519 (12)
Raw public key
c9:ba:1e:c4:96:da:cb:97:ae:d0:87:ad:e3:90:f3:98:
fb:d4:77:87:1e:e9:20:38:17:ec:0e:31:90:27:89:ff
Extensions
SubjectKeyIdentifier (1)
09:e4:33:58:25:56:55:0a:27:db:4a:19:bc:e2:d6:60:
88:47:22:b6
KeyUsage (2), critical
0x40: [cRLSign]
AuthorityKeyIdentifier (7)
Key Identifier
2f:45:e7:8d:2c:ae:df:36:8c:df:53:c3:90:05:d4:92:
45:0e:10:56
Signature Value
d4:6e:6a:8f:9f:d5:34:17:f3:6d:fe:56:cb:b8:ca:ce:
0f:c3:e5:9a:cb:e7:2c:d9:91:6b:3e:4c:50:22:d0:6d:
16:cc:9b:f9:ac:54:39:40:37:c9:54:33:64:41:94:fa:
e1:8f:f7:83:38:19:59:58:4a:21:bd:c0:e1:c6:cb:0b
A.2.3. OCSP Requestor Private Key and Certificate
A.2.3.1. OCSP Requestor Private Key
-----BEGIN PRIVATE KEY-----
MC4CAQAwBQYDK2VwBCIEIDoXZF67Rh+ENmXzefN4vLk/o2fK5q/otI2G1xQYtThH
-----END PRIVATE KEY-----
A.2.3.2. OCSP Requestor Certificate
A.2.3.2.1. Plain Hex
Liao, et al. Expires 7 January 2027 [Page 53]
Internet-Draft C509 Revocation July 2026
8B024212360C6F746573742063726C6F6373702D63611A6775D7001A69570A806E6F
6373702D726571756573746F720C582004530B1764EDD4B4E33AB44AF0F838961C00
7176D74B6A3546ECB7FD57320DD3860154DD51BDB2A2C791C062D4027856DBACF526
07F0BE210107542F45E78D2CAEDF368CDF53C39005D492450E10565840F8C6183ECF
8C3EFD50DD4942D172814C46EC0FC01DD586A597178DF864A0D9DA86B7CA17FC9F77
2FF04C80E98B60D5B4B62408A277A5B70D0D2A3F5ED5442D07
A.2.3.2.2. Textual Representation
Certificate
TBSCertificate
Certificate Type: 2
Serial Number
12:36
Signature Algorithm: Ed25519 (12)
Issuer : CN=test crlocsp-ca
Subject: CN=ocsp-requestor
Validity
Not Before: 2025-01-02T00:00:00Z
Not After : 2026-01-02T00:00:00Z
Subject Public Key Info:
algorithm: Ed25519 (12)
Raw public key
04:53:0b:17:64:ed:d4:b4:e3:3a:b4:4a:f0:f8:38:96:
1c:00:71:76:d7:4b:6a:35:46:ec:b7:fd:57:32:0d:d3
Extensions
SubjectKeyIdentifier (1)
dd:51:bd:b2:a2:c7:91:c0:62:d4:02:78:56:db:ac:f5:
26:07:f0:be
KeyUsage (2), critical
0x1: [digitalSignature]
AuthorityKeyIdentifier (7)
Key Identifier
2f:45:e7:8d:2c:ae:df:36:8c:df:53:c3:90:05:d4:92:
45:0e:10:56
Signature Value
f8:c6:18:3e:cf:8c:3e:fd:50:dd:49:42:d1:72:81:4c:
46:ec:0f:c0:1d:d5:86:a5:97:17:8d:f8:64:a0:d9:da:
86:b7:ca:17:fc:9f:77:2f:f0:4c:80:e9:8b:60:d5:b4:
b6:24:08:a2:77:a5:b7:0d:0d:2a:3f:5e:d5:44:2d:07
A.2.4. OCSP Responder Private Key and Certificate
A.2.4.1. OCSP Responder Private Key
-----BEGIN PRIVATE KEY-----
MC4CAQAwBQYDK2VwBCIEII5swSxWTjlZinUj+5kie//qjgBbzupdc0lmaHF9NkXl
-----END PRIVATE KEY-----
Liao, et al. Expires 7 January 2027 [Page 54]
Internet-Draft C509 Revocation July 2026
A.2.4.2. OCSP Responder Certificate
A.2.4.2.1. Plain Hex
8B024212350C6F746573742063726C6F6373702D63611A6775D7001A69570A806E6F
6373702D726573706F6E6465720C582081947BBC248AAC79738211A8D75BF92CB777
D994073DF23AE06380EF2C573976880154B5B4CAF35401D06151DF9629DB579DC8CC
A453A8210107542F45E78D2CAEDF368CDF53C39005D492450E105627095840A01B0C
BF3E34A4762D05404FD08A7AEC103035358314686D72B6159078C76E1D88597F3753
1886A3F52F256FD722192B289D6844014467F1F17F05ACBB7B660A
A.2.4.2.2. Textual Representation
Certificate
TBSCertificate
Certificate Type: 2
Serial Number
12:35
Signature Algorithm: Ed25519 (12)
Issuer : CN=test crlocsp-ca
Subject: CN=ocsp-responder
Validity
Not Before: 2025-01-02T00:00:00Z
Not After : 2026-01-02T00:00:00Z
Subject Public Key Info:
algorithm: Ed25519 (12)
Raw public key
81:94:7b:bc:24:8a:ac:79:73:82:11:a8:d7:5b:f9:2c:
b7:77:d9:94:07:3d:f2:3a:e0:63:80:ef:2c:57:39:76
Extensions
SubjectKeyIdentifier (1)
b5:b4:ca:f3:54:01:d0:61:51:df:96:29:db:57:9d:c8:
cc:a4:53:a8
KeyUsage (2), critical
0x1: [digitalSignature]
AuthorityKeyIdentifier (7)
Key Identifier
2f:45:e7:8d:2c:ae:df:36:8c:df:53:c3:90:05:d4:92:
45:0e:10:56
ExtendedKeyUsage (8), critical
OCSPSigning (9)
Signature Value
a0:1b:0c:bf:3e:34:a4:76:2d:05:40:4f:d0:8a:7a:ec:
10:30:35:35:83:14:68:6d:72:b6:15:90:78:c7:6e:1d:
88:59:7f:37:53:18:86:a3:f5:2f:25:6f:d7:22:19:2b:
28:9d:68:44:01:44:67:f1:f1:7f:05:ac:bb:7b:66:0a
Liao, et al. Expires 7 January 2027 [Page 55]
Internet-Draft C509 Revocation July 2026
A.3. CRL Examples
A.3.1. CRL Example Without Revoked Certificates
* Size reduction: 18%
* Verifiable with certificate in Appendix A.2.1.2
* Direct CRL
* Full CRL
* No revoked certificates
* Note that the X.509 CRL and the C509 CRL are not convertible.
A.3.1.1. X.509 CRL
PEM content (147 bytes):
-----BEGIN X509 CRL-----
MIGQMEQCAQEwBQYDK2VwMBoxGDAWBgNVBAMMD3Rlc3QgY3Jsb2NzcC1jYRcNMjUw
MTAyMDAwMDAwWhcNMjUwMTA5MDAwMDAwWjAFBgMrZXADQQBeSb215S+/7HT9HjQN
zeuuETZAjRIwCLxCIZatpkiov3ndsI7fjXcabny/kx9d5Ce39o3RcDG3QiDDdWOi
R5UK
-----END X509 CRL-----
A.3.1.2. C509 CRL
Plain Hex (120 bytes):
8B000C6F746573742063726C6F6373702D6361542F45E78D2CAEDF368CDF53C39005
D492450E1056011A6775D7001A00093A80F680F6584013834F4E38AA9F0DC5B8D21C
8650C776A6D961C31C894C36A71A6433F5ED7D30E67F787F13C7E4C349B2848A181F
DBBCE361A14C220021C4A267367AD5F1D90D
Textual Representation
Liao, et al. Expires 7 January 2027 [Page 56]
Internet-Draft C509 Revocation July 2026
C509CRL
TBSCertList
CRL Type: C509CRL (0)
Signature Algorithm: Ed25519 (12)
Authority Subject: CN=test crlocsp-ca
Authority Key Identifier:
2F:45:E7:8D:2C:AE:DF:36:8C:DF:53:C3:90:05:D4:92:
45:0E:10:56
CRL Number: 1
This Update: 2025-01-02T00:00:00Z
Next Update: 2025-01-09T00:00:00Z
Base CRL Number: <null>
Extensions: <empty>
revokedCertsList: <null>
Signature Value
13:83:4f:4e:38:aa:9f:0d:c5:b8:d2:1c:86:50:c7:76:
a6:d9:61:c3:1c:89:4c:36:a7:1a:64:33:f5:ed:7d:30:
e6:7f:78:7f:13:c7:e4:c3:49:b2:84:8a:18:1f:db:bc:
e3:61:a1:4c:22:00:21:c4:a2:67:36:7a:d5:f1:d9:0d
Annotated hex
0: 8B # C509CRL=array[11]
1: 00 # [0]. crlType=0
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 6F # [2]. authoritySubject=char[15]
4: 746573742063726C6F6373702D6361 # "test crlocsp-ca"
19: 54 # [3]. authorityKeyIdentifier=byte[20]
20: 2F45E78D2CAEDF368CDF53C39005D492450E1056
40: 01 # [4]. crlNumber=1
41: 1A 6775D700 # [5]. thisUpdate=1735776000:
# 2025-01-02T00:00:00Z
46: 1A 00093A80 # [6]. nextUpdate=604800: 2025-01-09T00:00:00Z
51: F6 # [7]. baseCrlNumber=<null>
52: 80 # [8]. crlExtensions=array[0]
53: F6 # [9]. revokedCertsList: <null>
54: 58 40 # [10]. signature value=byte[64]
56: 13834F4E38AA9F0DC5B8D21C8650C776A6D961C31C894C36A71A6433F5
85: ED7D30E67F787F13C7E4C349B2848A181FDBBCE361A14C220021C4A267
114: 367AD5F1D90D
A.3.2. CRL Example With Revoked Certificates
* Size reduction: 47%
* Verifiable with certificate in Appendix A.2.1.2
* Direct CRL
Liao, et al. Expires 7 January 2027 [Page 57]
Internet-Draft C509 Revocation July 2026
* Full CRL
* With revoked certificates
* With Per-Issuer Extension ExpiredCertsOnCRL
* Note that the X.509 CRL and the C509 CRL are not convertible.
A.3.2.1. X.509 CRL
PEM content (335 bytes):
-----BEGIN X509 CRL-----
MIIBSzCB/gIBATAFBgMrZXAwGjEYMBYGA1UEAwwPdGVzdCBjcmxvY3NwLWNhFw0y
NTAxMDcwMDEyMzRaFw0yNTAxMTQwMDEyMzRaMIG3MCECAhEiFw0yNTAxMDYwMDEy
MzRaMAwwCgYDVR0VBAMKAQYwIQICEjQXDTI1MDEwMTAwMTIzNFowDDAKBgNVHRUE
AwoBATAhAgIzRBcNMjUwMTA0MDAxMjM0WjAMMAoGA1UdFQQDCgEGMCECAlVmFw0y
NTAxMDIwMDEyMzRaMAwwCgYDVR0VBAMKAQYwEwICVngXDTI1MDEwNTAwMTIzNFow
FAIDAJq8Fw0yNTAxMDMwMDEyMzRaMAUGAytlcANBAAK0jdEbZtlvJDmhKAJQTklZ
WqS7xaN9gHvLC/8lvmqsSdY8T/1YbdkVGCyKsWuDSBGVFtrM2DrBzSDarRKctwY=
-----END X509 CRL-----
A.3.2.2. C509 CRL
Plain Hex (177 bytes):
8B000C6F746573742063726C6F6373702D6361542F45E78D2CAEDF368CDF53C39005
D492450E1056021A677C71721A00093A80F68085F6840302031A677488728218571A
677485805824112206978006123400000001334403F4800655660151800656780546
00009ABC02A30000F6584070BB7A38065FBCABFE615170F05A9A9FE83DC892D5F735
812B2A053AF4B300EB466BABB4F1A387CDCE90D8302C680B77AA61566423D7C235F7
BD31344CF7F405
Textual Representation
Liao, et al. Expires 7 January 2027 [Page 58]
Internet-Draft C509 Revocation July 2026
C509CRL
TBSCertList
CRL Type: C509CRL (0)
Signature Algorithm: Ed25519 (12)
Authority Subject: CN=test crlocsp-ca
Authority Key Identifier:
2F:45:E7:8D:2C:AE:DF:36:8C:DF:53:C3:90:05:D4:92:
45:0E:10:56
CRL Number: 2
This Update: 2025-01-07T00:12:34Z
Next Update: 2025-01-14T00:12:34Z
Base CRL Number: <null>
Extensions: <empty>
revokedCertsList:
PerIssuerRevokedCerts[0]
Issuer: <null>
RevokedCertsControl
Flags: sorted, with reason (0x3)
Serial number length: 2
Date length: 3
Base date: 2025-01-01T00:12:34Z
Extensions
ExpiredCertsOnCRL (87)
2025-01-01T00:00:00Z
RevokedCerts:
0x1122, 2025-01-06T00:12:34Z, certificateHold
0x1234, 2025-01-01T00:12:34Z, keyCompromise
0x3344, 2025-01-04T00:12:34Z, certificateHold
0x5566, 2025-01-02T00:12:34Z, certificateHold
0x5678, 2025-01-05T00:12:34Z, unspecified
0x9ABC, 2025-01-03T00:12:34Z, unspecified
RemovedFromCRLCerts: <null>
Signature Value
70:bb:7a:38:06:5f:bc:ab:fe:61:51:70:f0:5a:9a:9f:
e8:3d:c8:92:d5:f7:35:81:2b:2a:05:3a:f4:b3:00:eb:
46:6b:ab:b4:f1:a3:87:cd:ce:90:d8:30:2c:68:0b:77:
aa:61:56:64:23:d7:c2:35:f7:bd:31:34:4c:f7:f4:05
Annotated hex
0: 8B # C509CRL=array[11]
1: 00 # [0]. crlType=0
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 6F # [2]. authoritySubject=char[15]
4: 746573742063726C6F6373702D6361 # "test crlocsp-ca"
19: 54 # [3]. authorityKeyIdentifier=byte[20]
20: 2F45E78D2CAEDF368CDF53C39005D492450E1056
40: 02 # [4]. crlNumber=2
Liao, et al. Expires 7 January 2027 [Page 59]
Internet-Draft C509 Revocation July 2026
41: 1A 677C7172 # [5]. thisUpdate=1736208754:
# 2025-01-07T00:12:34Z
46: 1A 00093A80 # [6]. nextUpdate=604800: 2025-01-14T00:12:34Z
51: F6 # [7]. baseCrlNumber=<null>
52: 80 # [8]. crlExtensions=array[0]
53: 85 # [9]. revokedCertsList=array[5]
#---PerIssuedRevokedCerts[0]---
54: F6 # [0]. issuer=<null>
55: 84 # [1]. revokedCertsControl=array[4]
56: 03 # [0]. flags: sorted, with reason (0x3)
57: 02 # [1]. serialNumberLength=2
58: 03 # [2]. dateLength=3
59: 1A 67748872 # [3]. baseDate=1735690354:
# 2025-01-01T00:12:34Z
64: 82 # [2]. extensions=array[2]
#---extension[0]---
65: 18 57 # [0]. type=ExpiredCertsOnCRL (87)
67: 1A 67748580 # [1]. value=1735689600:
# 2025-01-01T00:00:00Z
72: 58 24 # [3]. revokedCerts=byte[36], 6 entries
#---entries[0]---
74: 1122 # CSN=1122
76: 069780 # date=069780: 2025-01-06T00:12:34Z
79: 06 # reason=6: certificateHold
#---entries[1]---
80: 1234 # CSN=1234
82: 000000 # date=000000: 2025-01-01T00:12:34Z
85: 01 # reason=1: keyCompromise
#---entries[2]---
86: 3344 # CSN=3344
88: 03F480 # date=03F480: 2025-01-04T00:12:34Z
91: 06 # reason=6: certificateHold
#---entries[3]---
92: 5566 # CSN=5566
94: 015180 # date=015180: 2025-01-02T00:12:34Z
97: 06 # reason=6: certificateHold
#---entries[4]---
98: 5678 # CSN=5678
100: 054600 # date=054600: 2025-01-05T00:12:34Z
103: 00 # reason=0: unspecified
#---entries[5]---
104: 9ABC # CSN=9ABC
106: 02A300 # date=02A300: 2025-01-03T00:12:34Z
109: 00 # reason=0: unspecified
110: F6 # [4]. removedFromCRLCerts=<null>
111: 58 40 # [10]. signature value=byte[64]
113: 70BB7A38065FBCABFE615170F05A9A9FE83DC892D5F735812B2A053AF4
142: B300EB466BABB4F1A387CDCE90D8302C680B77AA61566423D7C235F7BD
Liao, et al. Expires 7 January 2027 [Page 60]
Internet-Draft C509 Revocation July 2026
171: 31344CF7F405
A.3.3. Delta CRL Example With Revoked Certificates
* Size reduction: 52%
* Verifiable with certificate in Appendix A.2.1.2
* Direct CRL
* Delta CRL
* With revoked certificates
* With entries removed from CRL since last full CRL
* Note that the X.509 CRL and the C509 CRL are not convertible.
A.3.3.1. X.509 CRL
PEM content (335 bytes):
-----BEGIN X509 CRL-----
MIIBSzCB/gIBATAFBgMrZXAwGjEYMBYGA1UEAwwPdGVzdCBjcmxvY3NwLWNhFw0y
NTAxMDgwMDEyMzRaFw0yNTAxMTAwMDEyMzRaMIG3MCECAjQSFw0yNTAxMDcxMjEy
MzRaMAwwCgYDVR0VBAMKAQEwEwICeFYXDTI1MDEwODAwMTAzNFowFAIDALyaFw0y
NTAxMDgwMDA4MzRaMCECAhEiFw0yNTAxMDcxMzEyMzRaMAwwCgYDVR0VBAMKAQgw
IQICM0QXDTI1MDEwNzE0MTIzNFowDDAKBgNVHRUEAwoBCDAhAgJVZhcNMjUwMTA3
MTUxMjM0WjAMMAoGA1UdFQQDCgEIMAUGAytlcANBAKxSjqeefzjGdniA3bQCg3rL
d7rrJnfh8GfsWdawC9BHjK1G336hRYaxwLOtyQS4Mn80jjSwrN+bXg10spSA4gA=
-----END X509 CRL-----
A.3.3.2. C509 CRL
Plain Hex (160 bytes):
8B000C6F746573742063726C6F6373702D6361542F45E78D2CAEDF368CDF53C39005
D492450E1056031A677DC2F21A0002A300028085F6840302021A677D1A32804F3412
0000017856A84800BC9AA7D0004C11220E1033441C2055662A305840369C3E6412E9
D0537CD39EA1DA40C68C32B4EC0E5678650D6AF73677A5A0CF37F1CDE75D663DE374
9101F4354CCD6D8D05773887650046932B583C5365D7EB0B
Textual Representation
Liao, et al. Expires 7 January 2027 [Page 61]
Internet-Draft C509 Revocation July 2026
C509CRL
TBSCertList
CRL Type: C509CRL (0)
Signature Algorithm: Ed25519 (12)
Authority Subject: CN=test crlocsp-ca
Authority Key Identifier:
2F:45:E7:8D:2C:AE:DF:36:8C:DF:53:C3:90:05:D4:92:
45:0E:10:56
CRL Number: 3
This Update: 2025-01-08T00:12:34Z
Next Update: 2025-01-10T00:12:34Z
Base CRL Number: 2
Extensions: <empty>
revokedCertsList:
PerIssuerRevokedCerts[0]
Issuer: <null>
RevokedCertsControl
Flags: sorted, with reason (0x3)
Serial number length: 2
Date length: 2
Base date: 2025-01-07T12:12:34Z
Extensions: <empty>
RevokedCerts:
0x3412, 2025-01-07T12:12:34Z, keyCompromise
0x7856, 2025-01-08T00:10:34Z, unspecified
0xBC9A, 2025-01-08T00:08:34Z, unspecified
RemovedFromCRLCerts:
0x1122, 2025-01-07T13:12:34Z
0x3344, 2025-01-07T14:12:34Z
0x5566, 2025-01-07T15:12:34Z
Signature Value
36:9c:3e:64:12:e9:d0:53:7c:d3:9e:a1:da:40:c6:8c:
32:b4:ec:0e:56:78:65:0d:6a:f7:36:77:a5:a0:cf:37:
f1:cd:e7:5d:66:3d:e3:74:91:01:f4:35:4c:cd:6d:8d:
05:77:38:87:65:00:46:93:2b:58:3c:53:65:d7:eb:0b
Annotated hex
0: 8B # C509CRL=array[11]
1: 00 # [0]. crlType=0
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 6F # [2]. authoritySubject=char[15]
4: 746573742063726C6F6373702D6361 # "test crlocsp-ca"
19: 54 # [3]. authorityKeyIdentifier=byte[20]
20: 2F45E78D2CAEDF368CDF53C39005D492450E1056
40: 03 # [4]. crlNumber=3
41: 1A 677DC2F2 # [5]. thisUpdate=1736295154:
# 2025-01-08T00:12:34Z
Liao, et al. Expires 7 January 2027 [Page 62]
Internet-Draft C509 Revocation July 2026
46: 1A 0002A300 # [6]. nextUpdate=172800: 2025-01-10T00:12:34Z
51: 02 # [7]. baseCrlNumber=2
52: 80 # [8]. crlExtensions=array[0]
53: 85 # [9]. revokedCertsList=array[5]
#---PerIssuedRevokedCerts[0]---
54: F6 # [0]. issuer=<null>
55: 84 # [1]. revokedCertsControl=array[4]
56: 03 # [0]. flags: sorted, with reason (0x3)
57: 02 # [1]. serialNumberLength=2
58: 02 # [2]. dateLength=2
59: 1A 677D1A32 # [3]. baseDate=1736251954:
# 2025-01-07T12:12:34Z
64: 80 # [2]. extensions=array[0]
65: 4F # [3]. revokedCerts=byte[15], 3 entries
#---entries[0]---
66: 3412 # CSN=3412
68: 0000 # date=0000: 2025-01-07T12:12:34Z
70: 01 # reason=1: keyCompromise
#---entries[1]---
71: 7856 # CSN=7856
73: A848 # date=A848: 2025-01-08T00:10:34Z
75: 00 # reason=0: unspecified
#---entries[2]---
76: BC9A # CSN=BC9A
78: A7D0 # date=A7D0: 2025-01-08T00:08:34Z
80: 00 # reason=0: unspecified
81: 4C # [4]. removedFromCRLCerts=byte[12], 3
# entries
#---entries[0]---
82: 1122 # CSN=1122
84: 0E10 # date=0E10: 2025-01-07T13:12:34Z
#---entries[1]---
86: 3344 # CSN=3344
88: 1C20 # date=1C20: 2025-01-07T14:12:34Z
#---entries[2]---
90: 5566 # CSN=5566
92: 2A30 # date=2A30: 2025-01-07T15:12:34Z
94: 58 40 # [10]. signature value=byte[64]
96: 369C3E6412E9D0537CD39EA1DA40C68C32B4EC0E5678650D6AF73677A5
125: A0CF37F1CDE75D663DE3749101F4354CCD6D8D05773887650046932B58
154: 3C5365D7EB0B
A.3.4. Indirect CRL Example With Revoked Certificates
* Size reduction: 51%
* Verifiable with certificate in Appendix A.2.2.2
Liao, et al. Expires 7 January 2027 [Page 63]
Internet-Draft C509 Revocation July 2026
* Indirect CRL
* Full CRL
* With revoked certificates
* With two issuers
* Note that the X.509 CRL and the C509 CRL are not convertible.
A.3.4.1. X.509 CRL
PEM content (409 bytes):
-----BEGIN X509 CRL-----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-----END X509 CRL-----
A.3.4.2. C509 CRL
Plain Hex (202 bytes):
8B000C6A63726C2D7369676E65725409E433582556550A27DB4A19BCE2D660884722
B6041A677C71721A00093A80F6808A6F746573742063726C6F6373702D6361840302
031A6774887280521234000000015678054600009ABC02A30000F66A6578616D706C
65204341840302031A6775D9F28052112205460006334402A30006556600000006F6
5840F00D6270F91486A7F378D06F01A807E64E086BB366BE3A1592CE4A64BFFD621F
30E2AB93766B4F8818116AB7DA7BEDF7C3EBCBDEAC6D0455F5F5669712006205
Textual Representation
Liao, et al. Expires 7 January 2027 [Page 64]
Internet-Draft C509 Revocation July 2026
C509CRL
TBSCertList
CRL Type: C509CRL (0)
Signature Algorithm: Ed25519 (12)
Authority Subject: CN=crl-signer
Authority Key Identifier:
09:E4:33:58:25:56:55:0A:27:DB:4A:19:BC:E2:D6:60:
88:47:22:B6
CRL Number: 4
This Update: 2025-01-07T00:12:34Z
Next Update: 2025-01-14T00:12:34Z
Base CRL Number: <null>
Extensions: <empty>
revokedCertsList:
PerIssuerRevokedCerts[0]
Issuer: CN=test crlocsp-ca
RevokedCertsControl
Flags: sorted, with reason (0x3)
Serial number length: 2
Date length: 3
Base date: 2025-01-01T00:12:34Z
Extensions: <empty>
RevokedCerts:
0x1234, 2025-01-01T00:12:34Z, keyCompromise
0x5678, 2025-01-05T00:12:34Z, unspecified
0x9ABC, 2025-01-03T00:12:34Z, unspecified
RemovedFromCRLCerts: <null>
PerIssuerRevokedCerts[1]
Issuer: CN=example CA
RevokedCertsControl
Flags: sorted, with reason (0x3)
Serial number length: 2
Date length: 3
Base date: 2025-01-02T00:12:34Z
Extensions: <empty>
RevokedCerts:
0x1122, 2025-01-06T00:12:34Z, certificateHold
0x3344, 2025-01-04T00:12:34Z, certificateHold
0x5566, 2025-01-02T00:12:34Z, certificateHold
RemovedFromCRLCerts: <null>
Signature Value
f0:0d:62:70:f9:14:86:a7:f3:78:d0:6f:01:a8:07:e6:
4e:08:6b:b3:66:be:3a:15:92:ce:4a:64:bf:fd:62:1f:
30:e2:ab:93:76:6b:4f:88:18:11:6a:b7:da:7b:ed:f7:
c3:eb:cb:de:ac:6d:04:55:f5:f5:66:97:12:00:62:05
Annotated hex
Liao, et al. Expires 7 January 2027 [Page 65]
Internet-Draft C509 Revocation July 2026
0: 8B # C509CRL=array[11]
1: 00 # [0]. crlType=0
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 6A # [2]. authoritySubject=char[10]
4: 63726C2D7369676E6572 # "crl-signer"
14: 54 # [3]. authorityKeyIdentifier=byte[20]
15: 09E433582556550A27DB4A19BCE2D660884722B6
35: 04 # [4]. crlNumber=4
36: 1A 677C7172 # [5]. thisUpdate=1736208754:
# 2025-01-07T00:12:34Z
41: 1A 00093A80 # [6]. nextUpdate=604800: 2025-01-14T00:12:34Z
46: F6 # [7]. baseCrlNumber=<null>
47: 80 # [8]. crlExtensions=array[0]
48: 8A # [9]. revokedCertsList=array[10]
#---PerIssuedRevokedCerts[0]---
49: 6F # [0]. issuer=char[15]
50: 746573742063726C6F6373702D6361 # "test crlocsp-ca"
65: 84 # [1]. revokedCertsControl=array[4]
66: 03 # [0]. flags: sorted, with reason (0x3)
67: 02 # [1]. serialNumberLength=2
68: 03 # [2]. dateLength=3
69: 1A 67748872 # [3]. baseDate=1735690354:
# 2025-01-01T00:12:34Z
74: 80 # [2]. extensions=array[0]
75: 52 # [3]. revokedCerts=byte[18], 3 entries
#---entries[0]---
76: 1234 # CSN=1234
78: 000000 # date=000000: 2025-01-01T00:12:34Z
81: 01 # reason=1: keyCompromise
#---entries[1]---
82: 5678 # CSN=5678
84: 054600 # date=054600: 2025-01-05T00:12:34Z
87: 00 # reason=0: unspecified
#---entries[2]---
88: 9ABC # CSN=9ABC
90: 02A300 # date=02A300: 2025-01-03T00:12:34Z
93: 00 # reason=0: unspecified
94: F6 # [4]. removedFromCRLCerts=<null>
#---PerIssuedRevokedCerts[1]---
95: 6A # [5]. issuer=char[10]
96: 6578616D706C65204341 # "example CA"
106: 84 # [6]. revokedCertsControl=array[4]
107: 03 # [0]. flags: sorted, with reason (0x3)
108: 02 # [1]. serialNumberLength=2
109: 03 # [2]. dateLength=3
110: 1A 6775D9F2 # [3]. baseDate=1735776754:
# 2025-01-02T00:12:34Z
115: 80 # [7]. extensions=array[0]
Liao, et al. Expires 7 January 2027 [Page 66]
Internet-Draft C509 Revocation July 2026
116: 52 # [8]. revokedCerts=byte[18], 3 entries
#---entries[0]---
117: 1122 # CSN=1122
119: 054600 # date=054600: 2025-01-06T00:12:34Z
122: 06 # reason=6: certificateHold
#---entries[1]---
123: 3344 # CSN=3344
125: 02A300 # date=02A300: 2025-01-04T00:12:34Z
128: 06 # reason=6: certificateHold
#---entries[2]---
129: 5566 # CSN=5566
131: 000000 # date=000000: 2025-01-02T00:12:34Z
134: 06 # reason=6: certificateHold
135: F6 # [9]. removedFromCRLCerts=<null>
136: 58 40 # [10]. signature value=byte[64]
138: F00D6270F91486A7F378D06F01A807E64E086BB366BE3A1592CE4A64BF
167: FD621F30E2AB93766B4F8818116AB7DA7BEDF7C3EBCBDEAC6D0455F5F5
196: 669712006205
A.4. OCSP Request Examples
A.4.1. Simple OCSP Request Example
* Size reduction: 66%
* Simple OCSP Request (C509SimpleOCSPRequest)
* Note that the X.509 OCSP Request and the C509 OCSP Request are not
convertible.
A.4.1.1. X.509 OCSP Request
PEM content (152 bytes):
-----BEGIN OCSP REQUEST-----
MIGVMIGSMG0wazBpMA0GCWCGSAFlAwQCAQUABCAyU450hb03rkVPHw0rl1XXWLkf
bo46evOXoPQAYFxv+AQgzBHIdAoFCexNoUzliG5yNkwPY7YO1jR/E8Fu5yW3ZqIC
FBI0EjQSNBI0EjQSNBI0EjQSNBI0oiEwHzAdBgkrBgEFBQcwAQIEEBERERERERER
ERERERERERE=
-----END OCSP REQUEST-----
A.4.1.2. C509 OCSP Request
Plain Hex (51 bytes):
860200501111111111111111111111111111111148A01C73A5F3B063345410652787
FA0527BC2449A1BFC5AB31AA5A6F0D8D80
Liao, et al. Expires 7 January 2027 [Page 67]
Internet-Draft C509 Revocation July 2026
Textual Representation
C509SimpleOCSPRequest
Type: C509SimpleOCSPRequest (2)
Hash Algorithm: SHA256 (0)
IssuerCertHash:
a0:1c:73:a5:f3:b0:63:34
SerialNumberHash:
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
Extensions: <empty>
Annotated hex
0: 86 # C509OCSPRequest=array[6]
1: 02 # [0]. ocspRequestType=C509SimpleOCSPRequest
# (2)
2: 00 # [1]. hashAlgorithm=SHA256 (0)
3: 50 # [2]. nonce=byte[16]
4: 11111111111111111111111111111111
20: 48 # [3]. issuerCertHash=byte[8]
21: A01C73A5F3B06334
29: 54 # [4]. serialNumberHash=byte[20]
30: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
50: 80 # [5]. extensions=array[0]
A.4.2. Unsigned OCSP Request Example
* Size reduction: 73%
* Unsigned OCSP Request (C509UnsignedOCSPRequest)
* Note that the X.509 OCSP Request and the C509 OCSP Request are not
convertible.
A.4.2.1. X.509 OCSP Request
PEM content (483 bytes):
Liao, et al. Expires 7 January 2027 [Page 68]
Internet-Draft C509 Revocation July 2026
-----BEGIN OCSP REQUEST-----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-----END OCSP REQUEST-----
A.4.2.2. C509 OCSP Request
Plain Hex (132 bytes):
8500005011111111111111111111111111111111808648A01C73A5F3B06334808654
10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D805475D8BC4FBAFC6694467641E7
48DFD53A8B9D176D8054D1AC135D7DA29BDCF4DCA0D5281A51605B67840080482222
222222222222808254D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B80
Textual Representation
Liao, et al. Expires 7 January 2027 [Page 69]
Internet-Draft C509 Revocation July 2026
C509UnsignedOCSPRequest
Type: C509UnsignedOCSPRequest (0)
Hash Algorithm: SHA256 (0)
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
Requests
OcspPerIssuerRequest
issuerCertHash
a0:1c:73:a5:f3:b0:63:34
extensions: <empty>
singleRequests
SingleCertRequest
SerialNumberHash:
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Extensions: <empty>
SingleCertRequest
SerialNumberHash:
75:d8:bc:4f:ba:fc:66:94:46:76:41:e7:48:df:d5:3a:
8b:9d:17:6d
Extensions: <empty>
SingleCertRequest
SerialNumberHash:
d1:ac:13:5d:7d:a2:9b:dc:f4:dc:a0:d5:28:1a:51:60:
5b:67:84:00
Extensions: <empty>
OcspPerIssuerRequest
issuerCertHash
22:22:22:22:22:22:22:22
extensions: <empty>
singleRequests
SingleCertRequest
SerialNumberHash:
d3:a0:c1:e3:db:92:e8:f6:81:05:37:d4:5c:fa:ec:f6:
ce:41:7e:3b
Extensions: <empty>
Extensions: <empty>
Annotated hex
Liao, et al. Expires 7 January 2027 [Page 70]
Internet-Draft C509 Revocation July 2026
0: 85 # C509OCSPRequest=array[5]
1: 00 # [0]. ocspRequestType=C509UnsignedOCSPRequest
# (0)
2: 00 # [1]. hashAlgorithm=SHA256 (0)
3: 50 # [2]. nonce=byte[16]
4: 11111111111111111111111111111111
20: 80 # [3]. extensions=array[0]
21: 86 # [4]. requests=array[6]
#---PerIssuerRequests[0]---
22: 48 # [0]. issuerCertHash=byte[8]
23: A01C73A5F3B06334
31: 80 # [1]. extensions=array[0]
32: 86 # [2]. singleRequests=array[6]
#---SingleCertRequests[0]---
33: 54 # [0]. serialNumberHash=byte[20]
34: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
54: 80 # [1]. extensions=array[0]
#---SingleCertRequests[1]---
55: 54 # [2]. serialNumberHash=byte[20]
56: 75D8BC4FBAFC6694467641E748DFD53A8B9D176D
76: 80 # [3]. extensions=array[0]
#---SingleCertRequests[2]---
77: 54 # [4]. serialNumberHash=byte[20]
78: D1AC135D7DA29BDCF4DCA0D5281A51605B678400
98: 80 # [5]. extensions=array[0]
#---PerIssuerRequests[1]---
99: 48 # [3]. issuerCertHash=byte[8]
100: 2222222222222222
108: 80 # [4]. extensions=array[0]
109: 82 # [5]. singleRequests=array[2]
#---SingleCertRequests[0]---
110: 54 # [0]. serialNumberHash=byte[20]
111: D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B
131: 80 # [1]. extensions=array[0]
A.4.3. Signed OCSP Request Example Without Requestor's Certificate
* Size reduction: 65%
* Verifiable with certificate in Appendix A.2.3.2
* Signed OCSP Request (C509UnsignedOCSPRequest) without requestor's
certificate
* Note that the X.509 OCSP Request and the C509 OCSP Request are not
convertible.
Liao, et al. Expires 7 January 2027 [Page 71]
Internet-Draft C509 Revocation July 2026
A.4.3.1. X.509 OCSP Request
PEM content (592 bytes):
-----BEGIN OCSP REQUEST-----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-----END OCSP REQUEST-----
A.4.3.2. C509 OCSP Request
Plain Hex (209 bytes):
89010C0050111111111111111111111111111111114844F0528B56F35AD9808648A0
1C73A5F3B0633480865410652787FA0527BC2449A1BFC5AB31AA5A6F0D8D805475D8
BC4FBAFC6694467641E748DFD53A8B9D176D8054D1AC135D7DA29BDCF4DCA0D5281A
51605B67840080482222222222222222808254D3A0C1E3DB92E8F6810537D45CFAEC
F6CE417E3B80F658407DA70BE70D8C88F5150218B2F60A21320D26FAF8DC198F1665
4D54CB617A1C3C3F420B3F2FBF74C9B107D81D1815C2CE09B22EAF491313003C49D4
3AAB8D970B
Textual Representation
Liao, et al. Expires 7 January 2027 [Page 72]
Internet-Draft C509 Revocation July 2026
C509SignedOCSPRequest
TBSOCSPRequest
Type: C509SignedOCSPRequest (1)
Signature Algorithm: Ed25519 (12)
Hash Algorithm: SHA256 (0)
RequestorCertHash
44:f0:52:8b:56:f3:5a:d9
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
Extensions: <empty>
Requests
OcspPerIssuerRequest
issuerCertHash
a0:1c:73:a5:f3:b0:63:34
extensions: <empty>
singleRequests
SingleCertRequest
SerialNumberHash:
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Extensions: <empty>
SingleCertRequest
SerialNumberHash:
75:d8:bc:4f:ba:fc:66:94:46:76:41:e7:48:df:d5:3a:
8b:9d:17:6d
Extensions: <empty>
SingleCertRequest
SerialNumberHash:
d1:ac:13:5d:7d:a2:9b:dc:f4:dc:a0:d5:28:1a:51:60:
5b:67:84:00
Extensions: <empty>
OcspPerIssuerRequest
issuerCertHash
22:22:22:22:22:22:22:22
extensions: <empty>
singleRequests
SingleCertRequest
SerialNumberHash:
d3:a0:c1:e3:db:92:e8:f6:81:05:37:d4:5c:fa:ec:f6:
ce:41:7e:3b
Extensions: <empty>
Requestor Certs: null
Signature Value
7d:a7:0b:e7:0d:8c:88:f5:15:02:18:b2:f6:0a:21:32:
0d:26:fa:f8:dc:19:8f:16:65:4d:54:cb:61:7a:1c:3c:
3f:42:0b:3f:2f:bf:74:c9:b1:07:d8:1d:18:15:c2:ce:
09:b2:2e:af:49:13:13:00:3c:49:d4:3a:ab:8d:97:0b
Liao, et al. Expires 7 January 2027 [Page 73]
Internet-Draft C509 Revocation July 2026
Annotated hex
0: 89 # C509OCSPRequest=array[9]
1: 01 # [0]. ocspRequestType=C509SignedOCSPRequest
# (1)
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 00 # [2]. hashAlgorithm=SHA256 (0)
4: 50 # [3]. nonce=byte[16]
5: 11111111111111111111111111111111
21: 48 # [4]. requestorCertHash=byte[8]
22: 44F0528B56F35AD9
30: 80 # [5]. extensions=array[0]
31: 86 # [6]. requests=array[6]
#---PerIssuerRequests[0]---
32: 48 # [0]. issuerCertHash=byte[8]
33: A01C73A5F3B06334
41: 80 # [1]. extensions=array[0]
42: 86 # [2]. singleRequests=array[6]
#---SingleCertRequests[0]---
43: 54 # [0]. serialNumberHash=byte[20]
44: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
64: 80 # [1]. extensions=array[0]
#---SingleCertRequests[1]---
65: 54 # [2]. serialNumberHash=byte[20]
66: 75D8BC4FBAFC6694467641E748DFD53A8B9D176D
86: 80 # [3]. extensions=array[0]
#---SingleCertRequests[2]---
87: 54 # [4]. serialNumberHash=byte[20]
88: D1AC135D7DA29BDCF4DCA0D5281A51605B678400
108: 80 # [5]. extensions=array[0]
#---PerIssuerRequests[1]---
109: 48 # [3]. issuerCertHash=byte[8]
110: 2222222222222222
118: 80 # [4]. extensions=array[0]
119: 82 # [5]. singleRequests=array[2]
#---SingleCertRequests[0]---
120: 54 # [0]. serialNumberHash=byte[20]
121: D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B
141: 80 # [1]. extensions=array[0]
142: F6 # [7]. requestorCerts=<null>
143: 58 40 # [8]. signatureValue=byte[64]
145: 7DA70BE70D8C88F5150218B2F60A21320D26FAF8DC198F16654D54CB61
174: 7A1C3C3F420B3F2FBF74C9B107D81D1815C2CE09B22EAF491313003C49
203: D43AAB8D970B
Liao, et al. Expires 7 January 2027 [Page 74]
Internet-Draft C509 Revocation July 2026
A.4.4. Signed OCSP Request Example With Requestor's Certificate
* Size reduction: 60%
* Verifiable with certificate in Appendix A.2.3.2
* Signed OCSP Request (C509UnsignedOCSPRequest) with embedded
requestor's certificate
* Note that the X.509 OCSP Request and the C509 OCSP Request are not
convertible.
A.4.4.1. X.509 OCSP Request
PEM content (1043 bytes):
-----BEGIN OCSP REQUEST-----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-----END OCSP REQUEST-----
A.4.4.2. C509 OCSP Request
Plain Hex (420 bytes):
Liao, et al. Expires 7 January 2027 [Page 75]
Internet-Draft C509 Revocation July 2026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Textual Representation
C509SignedOCSPRequest
TBSOCSPRequest
Type: C509SignedOCSPRequest (1)
Signature Algorithm: Ed25519 (12)
Hash Algorithm: SHA256 (0)
RequestorCertHash
44:f0:52:8b:56:f3:5a:d9
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
Extensions
AcceptOCSPResponseTypes (93)
C509ErrorOCSPResponse (0)
C509BasicOCSPResponse (1)
preferredSignatureAlgorithms (94)
Preferred Signature Algorithm:
Signature Algorithm: Ed25519 (12)
Preferred Signature Algorithm:
Signature Algorithm: ecdsa-with-sha256 (0)
Public Key Algorithms:
EC public key on curve secp256r1 (1)
EC public key on curve brainpoolp256r1 (24)
Requests
OcspPerIssuerRequest
issuerCertHash
a0:1c:73:a5:f3:b0:63:34
extensions: <empty>
singleRequests
SingleCertRequest
SerialNumberHash:
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Extensions: <empty>
Liao, et al. Expires 7 January 2027 [Page 76]
Internet-Draft C509 Revocation July 2026
SingleCertRequest
SerialNumberHash:
75:d8:bc:4f:ba:fc:66:94:46:76:41:e7:48:df:d5:3a:
8b:9d:17:6d
Extensions: <empty>
SingleCertRequest
SerialNumberHash:
d1:ac:13:5d:7d:a2:9b:dc:f4:dc:a0:d5:28:1a:51:60:
5b:67:84:00
Extensions: <empty>
OcspPerIssuerRequest
issuerCertHash
22:22:22:22:22:22:22:22
extensions: <empty>
singleRequests
SingleCertRequest
SerialNumberHash:
d3:a0:c1:e3:db:92:e8:f6:81:05:37:d4:5c:fa:ec:f6:
ce:41:7e:3b
Extensions: <empty>
Requestor Certs
C509Certificate
8b:02:42:12:36:0c:6f:74:65:73:74:20:63:72:6c:6f:
63:73:70:2d:63:61:1a:67:75:d7:00:1a:69:57:0a:80:
6e:6f:63:73:70:2d:72:65:71:75:65:73:74:6f:72:0c:
58:20:04:53:0b:17:64:ed:d4:b4:e3:3a:b4:4a:f0:f8:
38:96:1c:00:71:76:d7:4b:6a:35:46:ec:b7:fd:57:32:
0d:d3:86:01:54:dd:51:bd:b2:a2:c7:91:c0:62:d4:02:
78:56:db:ac:f5:26:07:f0:be:21:01:07:54:2f:45:e7:
8d:2c:ae:df:36:8c:df:53:c3:90:05:d4:92:45:0e:10:
56:58:40:f8:c6:18:3e:cf:8c:3e:fd:50:dd:49:42:d1:
72:81:4c:46:ec:0f:c0:1d:d5:86:a5:97:17:8d:f8:64:
a0:d9:da:86:b7:ca:17:fc:9f:77:2f:f0:4c:80:e9:8b:
60:d5:b4:b6:24:08:a2:77:a5:b7:0d:0d:2a:3f:5e:d5:
44:2d:07
Signature Value
eb:f9:5f:92:81:2c:9d:f3:db:c7:c1:96:99:d5:25:44:
85:ad:dc:93:06:95:23:9d:1d:68:bf:79:88:f3:f1:b0:
c7:6a:58:8b:f4:2f:4f:cf:f3:73:c3:70:5a:eb:56:fc:
3b:6c:de:aa:f6:6d:a0:f5:bb:b7:35:f4:a1:cd:b0:04
Annotated hex
Liao, et al. Expires 7 January 2027 [Page 77]
Internet-Draft C509 Revocation July 2026
0: 89 # C509OCSPRequest=array[9]
1: 01 # [0]. ocspRequestType=C509SignedOCSPRequest
# (1)
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 00 # [2]. hashAlgorithm=SHA256 (0)
4: 50 # [3]. nonce=byte[16]
5: 11111111111111111111111111111111
21: 48 # [4]. requestorCertHash=byte[8]
22: 44F0528B56F35AD9
30: 84 # [5]. extensions=array[4]
#---extension[0]---
31: 18 5D # [0]. type=AcceptOCSPResponseTypes (93)
33: 82 # [1]. value=array[2]
34: 00 # [0]. C509ErrorOCSPResponse (0)
35: 01 # [1]. C509BasicOCSPResponse (1)
#---extension[1]---
36: 18 5E # [2]. type=preferredSignatureAlgorithms
# (94)
38: 84 # [3]. value=array[4]
#---preferredSignatureAlgorithms[0]---
39: 0C # [0]. sigIdentifier=Ed25519 (12)
40: F6 # [1]. pubKeyAlgIdentifiers=<null>
#---preferredSignatureAlgorithms[1]---
41: 00 # [2]. sigIdentifier=ecdsa-with-sha256 (0)
42: 82 # [3]. pubKeyAlgIdentifiers=array[2]
43: 01 # [0]. pubKeyAlgIdentifier=EC public key
# on curve secp256r1 (1)
44: 18 18 # [1]. pubKeyAlgIdentifier=EC public key
# on curve brainpoolp256r1 (24)
46: 86 # [6]. requests=array[6]
#---PerIssuerRequests[0]---
47: 48 # [0]. issuerCertHash=byte[8]
48: A01C73A5F3B06334
56: 80 # [1]. extensions=array[0]
57: 86 # [2]. singleRequests=array[6]
#---SingleCertRequests[0]---
58: 54 # [0]. serialNumberHash=byte[20]
59: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
79: 80 # [1]. extensions=array[0]
#---SingleCertRequests[1]---
80: 54 # [2]. serialNumberHash=byte[20]
81: 75D8BC4FBAFC6694467641E748DFD53A8B9D176D
101: 80 # [3]. extensions=array[0]
#---SingleCertRequests[2]---
102: 54 # [4]. serialNumberHash=byte[20]
103: D1AC135D7DA29BDCF4DCA0D5281A51605B678400
123: 80 # [5]. extensions=array[0]
#---PerIssuerRequests[1]---
Liao, et al. Expires 7 January 2027 [Page 78]
Internet-Draft C509 Revocation July 2026
124: 48 # [3]. issuerCertHash=byte[8]
125: 2222222222222222
133: 80 # [4]. extensions=array[0]
134: 82 # [5]. singleRequests=array[2]
#---SingleCertRequests[0]---
135: 54 # [0]. serialNumberHash=byte[20]
136: D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B
156: 80 # [1]. extensions=array[0]
157: 58 C3 # [7]. requestorCerts(COSE_C509)=byte[195]
159: 8B024212360C6F746573742063726C6F6373702D63611A6775D7001A69
188: 570A806E6F6373702D726571756573746F720C582004530B1764EDD4B4
217: E33AB44AF0F838961C007176D74B6A3546ECB7FD57320DD3860154DD51
246: BDB2A2C791C062D4027856DBACF52607F0BE210107542F45E78D2CAEDF
275: 368CDF53C39005D492450E10565840F8C6183ECF8C3EFD50DD4942D172
304: 814C46EC0FC01DD586A597178DF864A0D9DA86B7CA17FC9F772FF04C80
333: E98B60D5B4B62408A277A5B70D0D2A3F5ED5442D07
354: 58 40 # [8]. signatureValue=byte[64]
356: EBF95F92812C9DF3DBC7C19699D5254485ADDC930695239D1D68BF7988
385: F3F1B0C76A588BF42F4FCFF373C3705AEB56FC3B6CDEAAF66DA0F5BBB7
414: 35F4A1CDB004
A.4.5. Signed OCSP Request Example With Requestor's Certificate Chain
* Size reduction: 55%
* Verifiable with certificate in Appendix A.2.3.2
* Signed OCSP Request (C509UnsignedOCSPRequest) with embedded
requestor's certificate chain (2 certificates)
* Note that the X.509 OCSP Request and the C509 OCSP Request are not
convertible.
A.4.5.1. X.509 OCSP Request
PEM content (1379 bytes):
Liao, et al. Expires 7 January 2027 [Page 79]
Internet-Draft C509 Revocation July 2026
-----BEGIN OCSP REQUEST-----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-----END OCSP REQUEST-----
A.4.5.2. C509 OCSP Request
Plain Hex (625 bytes):
Liao, et al. Expires 7 January 2027 [Page 80]
Internet-Draft C509 Revocation July 2026
89010C0050111111111111111111111111111111114844F0528B56F35AD984185D82
0001185E840CF600820118188648A01C73A5F3B0633480865410652787FA0527BC24
49A1BFC5AB31AA5A6F0D8D805475D8BC4FBAFC6694467641E748DFD53A8B9D176D80
54D1AC135D7DA29BDCF4DCA0D5281A51605B67840080482222222222222222808254
D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B808258C38B024212360C6F746573
742063726C6F6373702D63611A6775D7001A69570A806E6F6373702D726571756573
746F720C582004530B1764EDD4B4E33AB44AF0F838961C007176D74B6A3546ECB7FD
57320DD3860154DD51BDB2A2C791C062D4027856DBACF52607F0BE210107542F45E7
8D2CAEDF368CDF53C39005D492450E10565840F8C6183ECF8C3EFD50DD4942D17281
4C46EC0FC01DD586A597178DF864A0D9DA86B7CA17FC9F772FF04C80E98B60D5B4B6
2408A277A5B70D0D2A3F5ED5442D0758CA8B0241010C73746573742063726C6F6373
702D726F6F7463611A677485801A6B36EC7F6F746573742063726C6F6373702D6361
0C58205EF8A355A001A7C50D23494701208131A4BB2AB920D40BFB0EE1F6AB28FF74
008801542F45E78D2CAEDF368CDF53C39005D492450E1056211860230107542DA3A4
03F7D2F4E0B3D8031A73BA8A839F557F0F5840E50465D60C02A2111EF3FC6E44F2A3
6008765B552351F9A3F5B2AA7C76F1F05D259847A4F4250B2E4B0AE2099762A2596D
3CC1DB2CCD180AA0A2D0E191310B0F584071D39CBD6611FD5B0C3092FCE58016B966
232851AC3167CD0CDEF47DF0F0BC738616EB65BB2BA509C8CF45EDBC9B784A4A7092
5E97AE152871E9D665C477500E
Textual Representation
C509SignedOCSPRequest
TBSOCSPRequest
Type: C509SignedOCSPRequest (1)
Signature Algorithm: Ed25519 (12)
Hash Algorithm: SHA256 (0)
RequestorCertHash
44:f0:52:8b:56:f3:5a:d9
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
Extensions
AcceptOCSPResponseTypes (93)
C509ErrorOCSPResponse (0)
C509BasicOCSPResponse (1)
preferredSignatureAlgorithms (94)
Preferred Signature Algorithm:
Signature Algorithm: Ed25519 (12)
Preferred Signature Algorithm:
Signature Algorithm: ecdsa-with-sha256 (0)
Public Key Algorithms:
EC public key on curve secp256r1 (1)
EC public key on curve brainpoolp256r1 (24)
Requests
OcspPerIssuerRequest
issuerCertHash
a0:1c:73:a5:f3:b0:63:34
extensions: <empty>
Liao, et al. Expires 7 January 2027 [Page 81]
Internet-Draft C509 Revocation July 2026
singleRequests
SingleCertRequest
SerialNumberHash:
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Extensions: <empty>
SingleCertRequest
SerialNumberHash:
75:d8:bc:4f:ba:fc:66:94:46:76:41:e7:48:df:d5:3a:
8b:9d:17:6d
Extensions: <empty>
SingleCertRequest
SerialNumberHash:
d1:ac:13:5d:7d:a2:9b:dc:f4:dc:a0:d5:28:1a:51:60:
5b:67:84:00
Extensions: <empty>
OcspPerIssuerRequest
issuerCertHash
22:22:22:22:22:22:22:22
extensions: <empty>
singleRequests
SingleCertRequest
SerialNumberHash:
d3:a0:c1:e3:db:92:e8:f6:81:05:37:d4:5c:fa:ec:f6:
ce:41:7e:3b
Extensions: <empty>
Requestor Certs
C509Certificate
8b:02:42:12:36:0c:6f:74:65:73:74:20:63:72:6c:6f:
63:73:70:2d:63:61:1a:67:75:d7:00:1a:69:57:0a:80:
6e:6f:63:73:70:2d:72:65:71:75:65:73:74:6f:72:0c:
58:20:04:53:0b:17:64:ed:d4:b4:e3:3a:b4:4a:f0:f8:
38:96:1c:00:71:76:d7:4b:6a:35:46:ec:b7:fd:57:32:
0d:d3:86:01:54:dd:51:bd:b2:a2:c7:91:c0:62:d4:02:
78:56:db:ac:f5:26:07:f0:be:21:01:07:54:2f:45:e7:
8d:2c:ae:df:36:8c:df:53:c3:90:05:d4:92:45:0e:10:
56:58:40:f8:c6:18:3e:cf:8c:3e:fd:50:dd:49:42:d1:
72:81:4c:46:ec:0f:c0:1d:d5:86:a5:97:17:8d:f8:64:
a0:d9:da:86:b7:ca:17:fc:9f:77:2f:f0:4c:80:e9:8b:
60:d5:b4:b6:24:08:a2:77:a5:b7:0d:0d:2a:3f:5e:d5:
44:2d:07
C509Certificate
8b:02:41:01:0c:73:74:65:73:74:20:63:72:6c:6f:63:
73:70:2d:72:6f:6f:74:63:61:1a:67:74:85:80:1a:6b:
36:ec:7f:6f:74:65:73:74:20:63:72:6c:6f:63:73:70:
2d:63:61:0c:58:20:5e:f8:a3:55:a0:01:a7:c5:0d:23:
49:47:01:20:81:31:a4:bb:2a:b9:20:d4:0b:fb:0e:e1:
f6:ab:28:ff:74:00:88:01:54:2f:45:e7:8d:2c:ae:df:
Liao, et al. Expires 7 January 2027 [Page 82]
Internet-Draft C509 Revocation July 2026
36:8c:df:53:c3:90:05:d4:92:45:0e:10:56:21:18:60:
23:01:07:54:2d:a3:a4:03:f7:d2:f4:e0:b3:d8:03:1a:
73:ba:8a:83:9f:55:7f:0f:58:40:e5:04:65:d6:0c:02:
a2:11:1e:f3:fc:6e:44:f2:a3:60:08:76:5b:55:23:51:
f9:a3:f5:b2:aa:7c:76:f1:f0:5d:25:98:47:a4:f4:25:
0b:2e:4b:0a:e2:09:97:62:a2:59:6d:3c:c1:db:2c:cd:
18:0a:a0:a2:d0:e1:91:31:0b:0f
Signature Value
71:d3:9c:bd:66:11:fd:5b:0c:30:92:fc:e5:80:16:b9:
66:23:28:51:ac:31:67:cd:0c:de:f4:7d:f0:f0:bc:73:
86:16:eb:65:bb:2b:a5:09:c8:cf:45:ed:bc:9b:78:4a:
4a:70:92:5e:97:ae:15:28:71:e9:d6:65:c4:77:50:0e
Annotated hex
0: 89 # C509OCSPRequest=array[9]
1: 01 # [0]. ocspRequestType=C509SignedOCSPRequest
# (1)
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 00 # [2]. hashAlgorithm=SHA256 (0)
4: 50 # [3]. nonce=byte[16]
5: 11111111111111111111111111111111
21: 48 # [4]. requestorCertHash=byte[8]
22: 44F0528B56F35AD9
30: 84 # [5]. extensions=array[4]
#---extension[0]---
31: 18 5D # [0]. type=AcceptOCSPResponseTypes (93)
33: 82 # [1]. value=array[2]
34: 00 # [0]. C509ErrorOCSPResponse (0)
35: 01 # [1]. C509BasicOCSPResponse (1)
#---extension[1]---
36: 18 5E # [2]. type=preferredSignatureAlgorithms
# (94)
38: 84 # [3]. value=array[4]
#---preferredSignatureAlgorithms[0]---
39: 0C # [0]. sigIdentifier=Ed25519 (12)
40: F6 # [1]. pubKeyAlgIdentifiers=<null>
#---preferredSignatureAlgorithms[1]---
41: 00 # [2]. sigIdentifier=ecdsa-with-sha256 (0)
42: 82 # [3]. pubKeyAlgIdentifiers=array[2]
43: 01 # [0]. pubKeyAlgIdentifier=EC public key
# on curve secp256r1 (1)
44: 18 18 # [1]. pubKeyAlgIdentifier=EC public key
# on curve brainpoolp256r1 (24)
46: 86 # [6]. requests=array[6]
#---PerIssuerRequests[0]---
47: 48 # [0]. issuerCertHash=byte[8]
48: A01C73A5F3B06334
Liao, et al. Expires 7 January 2027 [Page 83]
Internet-Draft C509 Revocation July 2026
56: 80 # [1]. extensions=array[0]
57: 86 # [2]. singleRequests=array[6]
#---SingleCertRequests[0]---
58: 54 # [0]. serialNumberHash=byte[20]
59: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
79: 80 # [1]. extensions=array[0]
#---SingleCertRequests[1]---
80: 54 # [2]. serialNumberHash=byte[20]
81: 75D8BC4FBAFC6694467641E748DFD53A8B9D176D
101: 80 # [3]. extensions=array[0]
#---SingleCertRequests[2]---
102: 54 # [4]. serialNumberHash=byte[20]
103: D1AC135D7DA29BDCF4DCA0D5281A51605B678400
123: 80 # [5]. extensions=array[0]
#---PerIssuerRequests[1]---
124: 48 # [3]. issuerCertHash=byte[8]
125: 2222222222222222
133: 80 # [4]. extensions=array[0]
134: 82 # [5]. singleRequests=array[2]
#---SingleCertRequests[0]---
135: 54 # [0]. serialNumberHash=byte[20]
136: D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B
156: 80 # [1]. extensions=array[0]
157: 82 # [7]. requestorCerts(COSE_C509)=array[2]
158: 58 C3 # [0]. C509CertData=byte[195]
160: 8B024212360C6F746573742063726C6F6373702D63611A6775D7001A
188: 69570A806E6F6373702D726571756573746F720C582004530B1764ED
216: D4B4E33AB44AF0F838961C007176D74B6A3546ECB7FD57320DD38601
244: 54DD51BDB2A2C791C062D4027856DBACF52607F0BE210107542F45E7
272: 8D2CAEDF368CDF53C39005D492450E10565840F8C6183ECF8C3EFD50
300: DD4942D172814C46EC0FC01DD586A597178DF864A0D9DA86B7CA17FC
328: 9F772FF04C80E98B60D5B4B62408A277A5B70D0D2A3F5ED5442D07
355: 58 CA # [1]. C509CertData=byte[202]
357: 8B0241010C73746573742063726C6F6373702D726F6F7463611A6774
385: 85801A6B36EC7F6F746573742063726C6F6373702D63610C58205EF8
413: A355A001A7C50D23494701208131A4BB2AB920D40BFB0EE1F6AB28FF
441: 74008801542F45E78D2CAEDF368CDF53C39005D492450E1056211860
469: 230107542DA3A403F7D2F4E0B3D8031A73BA8A839F557F0F5840E504
497: 65D60C02A2111EF3FC6E44F2A36008765B552351F9A3F5B2AA7C76F1
525: F05D259847A4F4250B2E4B0AE2099762A2596D3CC1DB2CCD180AA0A2
553: D0E191310B0F
559: 58 40 # [8]. signatureValue=byte[64]
561: 71D39CBD6611FD5B0C3092FCE58016B966232851AC3167CD0CDEF47DF0
590: F0BC738616EB65BB2BA509C8CF45EDBC9B784A4A70925E97AE152871E9
619: D665C477500E
A.5. OCSP Response Examples
Liao, et al. Expires 7 January 2027 [Page 84]
Internet-Draft C509 Revocation July 2026
A.5.1. Error OCSP Response Example
* Size reduction: 40%
* Error Response (C509ErrorOCSPResponse)
A.5.1.1. X.509 OCSP Response
PEM content (5 bytes):
-----BEGIN OCSP RESPONSE-----
MAMKAQY=
-----END OCSP RESPONSE-----
A.5.1.2. C509 OCSP Response
Plain Hex (3 bytes):
820006
Textual Representation
C509ErrorResponse
Type: C509ErrorOCSPResponse (0)
Status: unauthorized (6)
Annotated hex
0: 82 # C509OCSPResponse=array[2]
1: 00 # [0]. ocspResponseType=C509ErrorOCSPResponse
# (0)
2: 06 # [1]. responseStatus=unauthorized (6)
A.5.2. Simple OCSP Response Example
* Size reduction: 59%
* Verifiable with certificate in Appendix A.2.4.2
* Simple OCSP Response (C509SimpleOCSPResponse) without responder's
certificate
* Note that the X.509 OCSP response and the C509 OCSP response are
not convertible.
Liao, et al. Expires 7 January 2027 [Page 85]
Internet-Draft C509 Revocation July 2026
A.5.2.1. X.509 OCSP Response
PEM content (338 bytes):
-----BEGIN OCSP RESPONSE-----
MIIBTgoBAKCCAUcwggFDBgkrBgEFBQcwAQEEggE0MIIBMDCB46IWBBTq5ZqK6ar0
EEsV5Q6O4BcVF3QYrxgPMjAyNTAzMDMwMDAwMDBaMIGUMIGRMGkwDQYJYIZIAWUD
BAIBBQAEIDJTjnSFvTeuRU8fDSuXVddYuR9ujjp685eg9ABgXG/4BCDMEch0CgUJ
7E2hTOWIbnI2TA9jtg7WNH8TwW7nJbdmogIUEjQSNBI0EjQSNBI0EjQSNBI0EjSA
ABgPMjAyNTAzMDIxNjAwMDBaoBEYDzIwMjUwMzAzMDcwMDAwWqEhMB8wHQYJKwYB
BQUHMAECBBARERERERERERERERERERERMAUGAytlcANBAGEzM3X9KkpZLfpEMRoz
3TwWMLEfWkJkVHA++53Yj9QrrI6Sqry4t9AouNcGLORbv42mroG3GkYESuMSK3uG
Wgg=
-----END OCSP RESPONSE-----
A.5.2.2. C509 OCSP Response
Plain Hex (140 bytes):
8E020C005011111111111111111111111111111111480600867838E3311A48A01C73
A5F3B063345410652787FA0527BC2449A1BFC5AB31AA5A6F0D8D001A67C4F1003970
7F19627080F65840E3419955AEB3D74AD5BC7D32264E8976C3AB6F68643C6BF66CC2
F9352FF3E861A0BD1506C78B09D3FAE869D1FD3C87EF461CF6D2096EA0AC11FCFF5E
BC0FA70C
Textual Representation
Liao, et al. Expires 7 January 2027 [Page 86]
Internet-Draft C509 Revocation July 2026
C509SimpleOCSPResponse
TBSSimpleOCSPResponse
Type: C509SimpleOCSPResponse (2)
Signature Algorithm: Ed25519 (12)
Hash Algorithm: SHA256 (0)
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
ResponderCertHash
06:00:86:78:38:e3:31:1a
IssuerCertHash
a0:1c:73:a5:f3:b0:63:34
SerialNumberHash
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Cert Status: good
ProducedAt: 2025-03-03T00:00:00Z
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
Responder Certs: null
Signature Value
e3:41:99:55:ae:b3:d7:4a:d5:bc:7d:32:26:4e:89:76:
c3:ab:6f:68:64:3c:6b:f6:6c:c2:f9:35:2f:f3:e8:61:
a0:bd:15:06:c7:8b:09:d3:fa:e8:69:d1:fd:3c:87:ef:
46:1c:f6:d2:09:6e:a0:ac:11:fc:ff:5e:bc:0f:a7:0c
Annotated hex
Liao, et al. Expires 7 January 2027 [Page 87]
Internet-Draft C509 Revocation July 2026
0: 8E # C509OCSPResponse=array[14]
1: 02 # [0]. ocspResponseType=C509SimpleOCSPResponse
# (2)
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 00 # [2]. hashAlgorithm=SHA256 (0)
4: 50 # [3]. nonce=byte[16]
5: 11111111111111111111111111111111
21: 48 # [4]. responderCertHash=byte[8]
22: 0600867838E3311A
30: 48 # [5]. issuerCertHash=byte[8]
31: A01C73A5F3B06334
39: 54 # [6]. serialNumberHash=byte[20]
40: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
60: 00 # [7]. certStatus=good (0)
61: 1A 67C4F100 # [8]. producedAt=1740960000:
# 2025-03-03T00:00:00Z
66: 39 707F # [9]. thisUpdate=-28800: 2025-03-02T16:00:00Z
69: 19 6270 # [10]. nextUpdate=25200: 2025-03-03T07:00:00Z
72: 80 # [11]. extensions=array[0]
73: F6 # [12]. responderCerts=<null>
74: 58 40 # [13]. signatureValue=byte[64]
76: E3419955AEB3D74AD5BC7D32264E8976C3AB6F68643C6BF66CC2F9352F
105: F3E861A0BD1506C78B09D3FAE869D1FD3C87EF461CF6D2096EA0AC11FC
134: FF5EBC0FA70C
A.5.3. Basic OCSP Response Example Without Responder's Certificate
* Size reduction: 71%
* Verifiable with certificate in Appendix A.2.4.2
* Basic OCSP Response (C509BasicOCSPResponse) without responder's
certificate
* Note that the X.509 OCSP response and the C509 OCSP response are
not convertible.
A.5.3.1. X.509 OCSP Response
PEM content (845 bytes):
Liao, et al. Expires 7 January 2027 [Page 88]
Internet-Draft C509 Revocation July 2026
-----BEGIN OCSP RESPONSE-----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-----END OCSP RESPONSE-----
A.5.3.2. C509 OCSP Response
Plain Hex (248 bytes):
8A010C005011111111111111111111111111111111480600867838E3311A1A67C4F1
00808648A01C73A5F3B06334808F5410652787FA0527BC2449A1BFC5AB31AA5A6F0D
8D0039707F196270805475D8BC4FBAFC6694467641E748DFD53A8B9D176D0139707F
1962708054D1AC135D7DA29BDCF4DCA0D5281A51605B678400821A67C32F00043970
7F19627080482222222222222222808554D3A0C1E3DB92E8F6810537D45CFAECF6CE
417E3B0239707F19627080F65840E4869C57A66BAB501ACAEB7E5024105253D72F45
D349AE21FB941ABE4435F8A6C9D1CA5D2784AB30CF177FF075B5502AEAEE09C1146C
F490663EAED9243A760D
Textual Representation
C509BasicOCSPResponse
TBSBasicOCSPResponse
Type: C509BasicOCSPResponse (1)
Signature Algorithm: Ed25519 (12)
Hash Algorithm: SHA256 (0)
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
ResponderCertHash
06:00:86:78:38:e3:31:1a
ProducedAt: 2025-03-03T00:00:00Z
Extensions: <empty>
Responses
Liao, et al. Expires 7 January 2027 [Page 89]
Internet-Draft C509 Revocation July 2026
OcspPerIssuerResponse
IssuerCertHash
a0:1c:73:a5:f3:b0:63:34
Extensions: <empty>
SingleResponses
SingleCertResponse
SerialNumberHash:
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Cert Status: good
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
SingleCertResponse
SerialNumberHash:
75:d8:bc:4f:ba:fc:66:94:46:76:41:e7:48:df:d5:3a:
8b:9d:17:6d
Cert Status: not-issued
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
SingleCertResponse
SerialNumberHash:
d1:ac:13:5d:7d:a2:9b:dc:f4:dc:a0:d5:28:1a:51:60:
5b:67:84:00
Cert Status: revoked (superseded)
Revoked at 2025-03-01T16:00:00Z
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
OcspPerIssuerResponse
IssuerCertHash
22:22:22:22:22:22:22:22
Extensions: <empty>
SingleResponses
SingleCertResponse
SerialNumberHash:
d3:a0:c1:e3:db:92:e8:f6:81:05:37:d4:5c:fa:ec:f6:
ce:41:7e:3b
Cert Status: unknown
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
Responder Certs: null
Signature Value
e4:86:9c:57:a6:6b:ab:50:1a:ca:eb:7e:50:24:10:52:
53:d7:2f:45:d3:49:ae:21:fb:94:1a:be:44:35:f8:a6:
c9:d1:ca:5d:27:84:ab:30:cf:17:7f:f0:75:b5:50:2a:
Liao, et al. Expires 7 January 2027 [Page 90]
Internet-Draft C509 Revocation July 2026
ea:ee:09:c1:14:6c:f4:90:66:3e:ae:d9:24:3a:76:0d
Annotated hex
0: 8A # C509OCSPResponse=array[10]
1: 01 # [0]. ocspResponseType=C509BasicOCSPResponse
# (1)
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 00 # [2]. hashAlgorithm=SHA256 (0)
4: 50 # [3]. nonce=byte[16]
5: 11111111111111111111111111111111
21: 48 # [4]. responderCertHash=byte[8]
22: 0600867838E3311A
30: 1A 67C4F100 # [5]. producedAt=1740960000:
# 2025-03-03T00:00:00Z
35: 80 # [6]. extensions=array[0]
36: 86 # [7]. responses=array[6]
#---PerIssuerResponses[0]---
37: 48 # [0]. issuerCertHash=byte[8]
38: A01C73A5F3B06334
46: 80 # [1]. extensions=array[0]
47: 8F # [2]. singleResponses=array[15]
#---SingleCertResponses[0]---
48: 54 # [0]. serialNumberHash=byte[20]
49: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
69: 00 # [1]. certStatus=good (0)
70: 39 707F # [2]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
73: 19 6270 # [3]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
76: 80 # [4]. extensions=array[0]
#---SingleCertResponses[1]---
77: 54 # [5]. serialNumberHash=byte[20]
78: 75D8BC4FBAFC6694467641E748DFD53A8B9D176D
98: 01 # [6]. certStatus=not-issued (1)
99: 39 707F # [7]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
102: 19 6270 # [8]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
105: 80 # [9]. extensions=array[0]
#---SingleCertResponses[2]---
106: 54 # [10]. serialNumberHash=byte[20]
107: D1AC135D7DA29BDCF4DCA0D5281A51605B678400
127: 82 # [11]. certStatus=array[2]
128: 1A 67C32F00 # [0]. revocationTime=1740844800:
# 2025-03-01T16:00:00Z
133: 04 # [1]. revocationReason=superseded (4)
134: 39 707F # [12]. thisUpdate=-28800:
Liao, et al. Expires 7 January 2027 [Page 91]
Internet-Draft C509 Revocation July 2026
# 2025-03-02T16:00:00Z
137: 19 6270 # [13]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
140: 80 # [14]. extensions=array[0]
#---PerIssuerResponses[1]---
141: 48 # [3]. issuerCertHash=byte[8]
142: 2222222222222222
150: 80 # [4]. extensions=array[0]
151: 85 # [5]. singleResponses=array[5]
#---SingleCertResponses[0]---
152: 54 # [0]. serialNumberHash=byte[20]
153: D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B
173: 02 # [1]. certStatus=unknown (2)
174: 39 707F # [2]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
177: 19 6270 # [3]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
180: 80 # [4]. extensions=array[0]
181: F6 # [8]. responderCerts=<null>
182: 58 40 # [9]. signature value=byte[64]
184: E4869C57A66BAB501ACAEB7E5024105253D72F45D349AE21FB941ABE44
213: 35F8A6C9D1CA5D2784AB30CF177FF075B5502AEAEE09C1146CF490663E
242: AED9243A760D
A.5.4. Basic OCSP Response Example With Responder's Certificate
* Size reduction: 62%
* Verifiable with certificate in Appendix A.2.4.2
* Basic OCSP Response (C509BasicOCSPResponse) with embedded
responder's certificate
* Note that the X.509 OCSP response and the C509 OCSP response are
not convertible.
A.5.4.1. X.509 OCSP Response
PEM content (1189 bytes):
Liao, et al. Expires 7 January 2027 [Page 92]
Internet-Draft C509 Revocation July 2026
-----BEGIN OCSP RESPONSE-----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-----END OCSP RESPONSE-----
A.5.4.2. C509 OCSP Response
Plain Hex (446 bytes):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Textual Representation
Liao, et al. Expires 7 January 2027 [Page 93]
Internet-Draft C509 Revocation July 2026
C509BasicOCSPResponse
TBSBasicOCSPResponse
Type: C509BasicOCSPResponse (1)
Signature Algorithm: Ed25519 (12)
Hash Algorithm: SHA256 (0)
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
ResponderCertHash
06:00:86:78:38:e3:31:1a
ProducedAt: 2025-03-03T00:00:00Z
Extensions: <empty>
Responses
OcspPerIssuerResponse
IssuerCertHash
a0:1c:73:a5:f3:b0:63:34
Extensions: <empty>
SingleResponses
SingleCertResponse
SerialNumberHash:
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Cert Status: good
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
SingleCertResponse
SerialNumberHash:
75:d8:bc:4f:ba:fc:66:94:46:76:41:e7:48:df:d5:3a:
8b:9d:17:6d
Cert Status: not-issued
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
SingleCertResponse
SerialNumberHash:
d1:ac:13:5d:7d:a2:9b:dc:f4:dc:a0:d5:28:1a:51:60:
5b:67:84:00
Cert Status: revoked (superseded)
Revoked at 2025-03-01T16:00:00Z
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
OcspPerIssuerResponse
IssuerCertHash
22:22:22:22:22:22:22:22
Extensions: <empty>
SingleResponses
SingleCertResponse
Liao, et al. Expires 7 January 2027 [Page 94]
Internet-Draft C509 Revocation July 2026
SerialNumberHash:
d3:a0:c1:e3:db:92:e8:f6:81:05:37:d4:5c:fa:ec:f6:
ce:41:7e:3b
Cert Status: unknown
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
Responder Certs
C509Certificate
8b:02:42:12:35:0c:6f:74:65:73:74:20:63:72:6c:6f:
63:73:70:2d:63:61:1a:67:75:d7:00:1a:69:57:0a:80:
6e:6f:63:73:70:2d:72:65:73:70:6f:6e:64:65:72:0c:
58:20:81:94:7b:bc:24:8a:ac:79:73:82:11:a8:d7:5b:
f9:2c:b7:77:d9:94:07:3d:f2:3a:e0:63:80:ef:2c:57:
39:76:88:01:54:b5:b4:ca:f3:54:01:d0:61:51:df:96:
29:db:57:9d:c8:cc:a4:53:a8:21:01:07:54:2f:45:e7:
8d:2c:ae:df:36:8c:df:53:c3:90:05:d4:92:45:0e:10:
56:27:09:58:40:a0:1b:0c:bf:3e:34:a4:76:2d:05:40:
4f:d0:8a:7a:ec:10:30:35:35:83:14:68:6d:72:b6:15:
90:78:c7:6e:1d:88:59:7f:37:53:18:86:a3:f5:2f:25:
6f:d7:22:19:2b:28:9d:68:44:01:44:67:f1:f1:7f:05:
ac:bb:7b:66:0a
Signature Value
00:85:ea:27:96:9e:5a:16:2e:a3:1d:37:15:22:f6:2f:
0d:f2:78:27:22:25:de:ad:6f:17:3c:42:d5:48:21:42:
a3:f0:32:87:28:50:a4:e2:c2:d9:a7:59:a0:f4:60:e1:
25:0b:6f:de:bb:66:36:b3:67:2c:a0:2e:fb:88:0a:04
Annotated hex
0: 8A # C509OCSPResponse=array[10]
1: 01 # [0]. ocspResponseType=C509BasicOCSPResponse
# (1)
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 00 # [2]. hashAlgorithm=SHA256 (0)
4: 50 # [3]. nonce=byte[16]
5: 11111111111111111111111111111111
21: 48 # [4]. responderCertHash=byte[8]
22: 0600867838E3311A
30: 1A 67C4F100 # [5]. producedAt=1740960000:
# 2025-03-03T00:00:00Z
35: 80 # [6]. extensions=array[0]
36: 86 # [7]. responses=array[6]
#---PerIssuerResponses[0]---
37: 48 # [0]. issuerCertHash=byte[8]
38: A01C73A5F3B06334
46: 80 # [1]. extensions=array[0]
47: 8F # [2]. singleResponses=array[15]
Liao, et al. Expires 7 January 2027 [Page 95]
Internet-Draft C509 Revocation July 2026
#---SingleCertResponses[0]---
48: 54 # [0]. serialNumberHash=byte[20]
49: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
69: 00 # [1]. certStatus=good (0)
70: 39 707F # [2]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
73: 19 6270 # [3]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
76: 80 # [4]. extensions=array[0]
#---SingleCertResponses[1]---
77: 54 # [5]. serialNumberHash=byte[20]
78: 75D8BC4FBAFC6694467641E748DFD53A8B9D176D
98: 01 # [6]. certStatus=not-issued (1)
99: 39 707F # [7]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
102: 19 6270 # [8]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
105: 80 # [9]. extensions=array[0]
#---SingleCertResponses[2]---
106: 54 # [10]. serialNumberHash=byte[20]
107: D1AC135D7DA29BDCF4DCA0D5281A51605B678400
127: 82 # [11]. certStatus=array[2]
128: 1A 67C32F00 # [0]. revocationTime=1740844800:
# 2025-03-01T16:00:00Z
133: 04 # [1]. revocationReason=superseded (4)
134: 39 707F # [12]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
137: 19 6270 # [13]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
140: 80 # [14]. extensions=array[0]
#---PerIssuerResponses[1]---
141: 48 # [3]. issuerCertHash=byte[8]
142: 2222222222222222
150: 80 # [4]. extensions=array[0]
151: 85 # [5]. singleResponses=array[5]
#---SingleCertResponses[0]---
152: 54 # [0]. serialNumberHash=byte[20]
153: D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B
173: 02 # [1]. certStatus=unknown (2)
174: 39 707F # [2]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
177: 19 6270 # [3]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
180: 80 # [4]. extensions=array[0]
181: 58 C5 # [8]. responderCerts(COSE_C509)=byte[197]
183: 8B024212350C6F746573742063726C6F6373702D63611A6775D7001A69
212: 570A806E6F6373702D726573706F6E6465720C582081947BBC248AAC79
241: 738211A8D75BF92CB777D994073DF23AE06380EF2C573976880154B5B4
Liao, et al. Expires 7 January 2027 [Page 96]
Internet-Draft C509 Revocation July 2026
270: CAF35401D06151DF9629DB579DC8CCA453A8210107542F45E78D2CAEDF
299: 368CDF53C39005D492450E105627095840A01B0CBF3E34A4762D05404F
328: D08A7AEC103035358314686D72B6159078C76E1D88597F37531886A3F5
357: 2F256FD722192B289D6844014467F1F17F05ACBB7B660A
380: 58 40 # [9]. signature value=byte[64]
382: 0085EA27969E5A162EA31D371522F62F0DF278272225DEAD6F173C42D5
411: 482142A3F032872850A4E2C2D9A759A0F460E1250B6FDEBB6636B3672C
440: A02EFB880A04
A.5.5. Basic OCSP Response Example With Responder's Certificate Chain
* Size reduction: 57%
* Verifiable with certificate in Appendix A.2.4.2
* Basic OCSP Response (C509BasicOCSPResponse) with embedded
responder's certificate chain (2 certificates)
* Note that the X.509 OCSP response and the C509 OCSP response are
not convertible.
A.5.5.1. X.509 OCSP Response
PEM content (1525 bytes):
Liao, et al. Expires 7 January 2027 [Page 97]
Internet-Draft C509 Revocation July 2026
-----BEGIN OCSP RESPONSE-----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-----END OCSP RESPONSE-----
A.5.5.2. C509 OCSP Response
Plain Hex (651 bytes):
Liao, et al. Expires 7 January 2027 [Page 98]
Internet-Draft C509 Revocation July 2026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Textual Representation
C509BasicOCSPResponse
TBSBasicOCSPResponse
Type: C509BasicOCSPResponse (1)
Signature Algorithm: Ed25519 (12)
Hash Algorithm: SHA256 (0)
Nonce
11:11:11:11:11:11:11:11:11:11:11:11:11:11:11:11
ResponderCertHash
06:00:86:78:38:e3:31:1a
ProducedAt: 2025-03-03T00:00:00Z
Extensions: <empty>
Responses
OcspPerIssuerResponse
IssuerCertHash
a0:1c:73:a5:f3:b0:63:34
Extensions: <empty>
SingleResponses
SingleCertResponse
SerialNumberHash:
10:65:27:87:fa:05:27:bc:24:49:a1:bf:c5:ab:31:aa:
5a:6f:0d:8d
Cert Status: good
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
Liao, et al. Expires 7 January 2027 [Page 99]
Internet-Draft C509 Revocation July 2026
SingleCertResponse
SerialNumberHash:
75:d8:bc:4f:ba:fc:66:94:46:76:41:e7:48:df:d5:3a:
8b:9d:17:6d
Cert Status: not-issued
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
SingleCertResponse
SerialNumberHash:
d1:ac:13:5d:7d:a2:9b:dc:f4:dc:a0:d5:28:1a:51:60:
5b:67:84:00
Cert Status: revoked (superseded)
Revoked at 2025-03-01T16:00:00Z
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
OcspPerIssuerResponse
IssuerCertHash
22:22:22:22:22:22:22:22
Extensions: <empty>
SingleResponses
SingleCertResponse
SerialNumberHash:
d3:a0:c1:e3:db:92:e8:f6:81:05:37:d4:5c:fa:ec:f6:
ce:41:7e:3b
Cert Status: unknown
This Update: -28800, 2025-03-02T16:00:00Z
Next Update: 25200, 2025-03-03T07:00:00Z
Extensions: <empty>
Responder Certs
C509Certificate
8b:02:42:12:35:0c:6f:74:65:73:74:20:63:72:6c:6f:
63:73:70:2d:63:61:1a:67:75:d7:00:1a:69:57:0a:80:
6e:6f:63:73:70:2d:72:65:73:70:6f:6e:64:65:72:0c:
58:20:81:94:7b:bc:24:8a:ac:79:73:82:11:a8:d7:5b:
f9:2c:b7:77:d9:94:07:3d:f2:3a:e0:63:80:ef:2c:57:
39:76:88:01:54:b5:b4:ca:f3:54:01:d0:61:51:df:96:
29:db:57:9d:c8:cc:a4:53:a8:21:01:07:54:2f:45:e7:
8d:2c:ae:df:36:8c:df:53:c3:90:05:d4:92:45:0e:10:
56:27:09:58:40:a0:1b:0c:bf:3e:34:a4:76:2d:05:40:
4f:d0:8a:7a:ec:10:30:35:35:83:14:68:6d:72:b6:15:
90:78:c7:6e:1d:88:59:7f:37:53:18:86:a3:f5:2f:25:
6f:d7:22:19:2b:28:9d:68:44:01:44:67:f1:f1:7f:05:
ac:bb:7b:66:0a
C509Certificate
8b:02:41:01:0c:73:74:65:73:74:20:63:72:6c:6f:63:
73:70:2d:72:6f:6f:74:63:61:1a:67:74:85:80:1a:6b:
Liao, et al. Expires 7 January 2027 [Page 100]
Internet-Draft C509 Revocation July 2026
36:ec:7f:6f:74:65:73:74:20:63:72:6c:6f:63:73:70:
2d:63:61:0c:58:20:5e:f8:a3:55:a0:01:a7:c5:0d:23:
49:47:01:20:81:31:a4:bb:2a:b9:20:d4:0b:fb:0e:e1:
f6:ab:28:ff:74:00:88:01:54:2f:45:e7:8d:2c:ae:df:
36:8c:df:53:c3:90:05:d4:92:45:0e:10:56:21:18:60:
23:01:07:54:2d:a3:a4:03:f7:d2:f4:e0:b3:d8:03:1a:
73:ba:8a:83:9f:55:7f:0f:58:40:e5:04:65:d6:0c:02:
a2:11:1e:f3:fc:6e:44:f2:a3:60:08:76:5b:55:23:51:
f9:a3:f5:b2:aa:7c:76:f1:f0:5d:25:98:47:a4:f4:25:
0b:2e:4b:0a:e2:09:97:62:a2:59:6d:3c:c1:db:2c:cd:
18:0a:a0:a2:d0:e1:91:31:0b:0f
Signature Value
b6:33:c9:59:80:73:e3:92:08:76:fe:12:b8:6a:d3:24:
22:e7:f2:c2:36:11:77:a6:d5:90:f2:0b:eb:ba:a1:ef:
df:94:a0:a9:44:ac:8c:a6:76:79:ca:04:ce:af:32:7c:
12:cb:9f:1c:2d:ca:ca:9d:2e:94:9b:fe:a7:55:c4:05
Annotated hex
0: 8A # C509OCSPResponse=array[10]
1: 01 # [0]. ocspResponseType=C509BasicOCSPResponse
# (1)
2: 0C # [1]. signatureAlgorithm=Ed25519 (12)
3: 00 # [2]. hashAlgorithm=SHA256 (0)
4: 50 # [3]. nonce=byte[16]
5: 11111111111111111111111111111111
21: 48 # [4]. responderCertHash=byte[8]
22: 0600867838E3311A
30: 1A 67C4F100 # [5]. producedAt=1740960000:
# 2025-03-03T00:00:00Z
35: 80 # [6]. extensions=array[0]
36: 86 # [7]. responses=array[6]
#---PerIssuerResponses[0]---
37: 48 # [0]. issuerCertHash=byte[8]
38: A01C73A5F3B06334
46: 80 # [1]. extensions=array[0]
47: 8F # [2]. singleResponses=array[15]
#---SingleCertResponses[0]---
48: 54 # [0]. serialNumberHash=byte[20]
49: 10652787FA0527BC2449A1BFC5AB31AA5A6F0D8D
69: 00 # [1]. certStatus=good (0)
70: 39 707F # [2]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
73: 19 6270 # [3]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
76: 80 # [4]. extensions=array[0]
#---SingleCertResponses[1]---
77: 54 # [5]. serialNumberHash=byte[20]
Liao, et al. Expires 7 January 2027 [Page 101]
Internet-Draft C509 Revocation July 2026
78: 75D8BC4FBAFC6694467641E748DFD53A8B9D176D
98: 01 # [6]. certStatus=not-issued (1)
99: 39 707F # [7]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
102: 19 6270 # [8]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
105: 80 # [9]. extensions=array[0]
#---SingleCertResponses[2]---
106: 54 # [10]. serialNumberHash=byte[20]
107: D1AC135D7DA29BDCF4DCA0D5281A51605B678400
127: 82 # [11]. certStatus=array[2]
128: 1A 67C32F00 # [0]. revocationTime=1740844800:
# 2025-03-01T16:00:00Z
133: 04 # [1]. revocationReason=superseded (4)
134: 39 707F # [12]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
137: 19 6270 # [13]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
140: 80 # [14]. extensions=array[0]
#---PerIssuerResponses[1]---
141: 48 # [3]. issuerCertHash=byte[8]
142: 2222222222222222
150: 80 # [4]. extensions=array[0]
151: 85 # [5]. singleResponses=array[5]
#---SingleCertResponses[0]---
152: 54 # [0]. serialNumberHash=byte[20]
153: D3A0C1E3DB92E8F6810537D45CFAECF6CE417E3B
173: 02 # [1]. certStatus=unknown (2)
174: 39 707F # [2]. thisUpdate=-28800:
# 2025-03-02T16:00:00Z
177: 19 6270 # [3]. nextUpdate=25200:
# 2025-03-03T07:00:00Z
180: 80 # [4]. extensions=array[0]
181: 82 # [8]. responderCerts(COSE_C509)=array[2]
182: 58 C5 # [0]. C509CertData=byte[197]
184: 8B024212350C6F746573742063726C6F6373702D63611A6775D7001A
212: 69570A806E6F6373702D726573706F6E6465720C582081947BBC248A
240: AC79738211A8D75BF92CB777D994073DF23AE06380EF2C5739768801
268: 54B5B4CAF35401D06151DF9629DB579DC8CCA453A8210107542F45E7
296: 8D2CAEDF368CDF53C39005D492450E105627095840A01B0CBF3E34A4
324: 762D05404FD08A7AEC103035358314686D72B6159078C76E1D88597F
352: 37531886A3F52F256FD722192B289D6844014467F1F17F05ACBB7B66
380: 0A
381: 58 CA # [1]. C509CertData=byte[202]
383: 8B0241010C73746573742063726C6F6373702D726F6F7463611A6774
411: 85801A6B36EC7F6F746573742063726C6F6373702D63610C58205EF8
439: A355A001A7C50D23494701208131A4BB2AB920D40BFB0EE1F6AB28FF
467: 74008801542F45E78D2CAEDF368CDF53C39005D492450E1056211860
Liao, et al. Expires 7 January 2027 [Page 102]
Internet-Draft C509 Revocation July 2026
495: 230107542DA3A403F7D2F4E0B3D8031A73BA8A839F557F0F5840E504
523: 65D60C02A2111EF3FC6E44F2A36008765B552351F9A3F5B2AA7C76F1
551: F05D259847A4F4250B2E4B0AE2099762A2596D3CC1DB2CCD180AA0A2
579: D0E191310B0F
585: 58 40 # [9]. signature value=byte[64]
587: B633C9598073E3920876FE12B86AD32422E7F2C2361177A6D590F20BEB
616: BAA1EFDF94A0A944AC8CA67679CA04CEAF327C12CB9F1C2DCACA9D2E94
645: 9BFEA755C405
Acknowledgments
The authors thank xxx for reviewing and commenting on intermediate
versions of the draft.
Authors' Addresses
Lijun Liao
NIO
Email: lijun.liao@nio.io
Marco Tiloca
RISE AB
Email: marco.tiloca@ri.se
Joel Höglund
RISE AB
Email: joel.hoglund@ri.se
Rikard Höglund
RISE AB
Email: rikard.hoglund@ri.se
Shahid Raza
University of Glasgow
Email: shahid.raza@glasgow.ac.uk
Liao, et al. Expires 7 January 2027 [Page 103]