CBOR Encoded X.509 Certificates (C509 Certificates)
draft-ietf-cose-cbor-encoded-cert-18
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Active".
|
|
|---|---|---|---|
| Authors | John Preuß Mattsson , Göran Selander , Shahid Raza , Joel Höglund , Martin Furuhed , Lijun Liao | ||
| Last updated | 2026-04-30 (Latest revision 2026-04-22) | ||
| Replaces | draft-mattsson-cose-cbor-cert-compress | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Reviews | |||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | Submitted to IESG for Publication | |
| Associated WG milestone |
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||
| Document shepherd | Ivaylo Petrov | ||
| Shepherd write-up | Show Last changed 2025-09-22 | ||
| IESG | IESG state | IESG Evaluation::AD Followup | |
| Consensus boilerplate | Yes | ||
| Telechat date |
(None)
Has enough positions to pass. |
||
| Responsible AD | Christopher Inacio | ||
| Send notices to | ivaylopetrov@google.com | ||
| IANA | IANA review state | IANA OK - Actions Needed | |
| IANA expert review state | Expert Reviews OK | ||
| IANA expert review comments | All expert approvals have been received. |
draft-ietf-cose-cbor-encoded-cert-18
Network Working Group J. Preuß Mattsson
Internet-Draft G. Selander
Updates: 6698 (if approved) Ericsson AB
Intended status: Standards Track S. Raza
Expires: 24 October 2026 University of Glasgow
J. Höglund
RISE AB
M. Furuhed
IN Groupe
L. Liao
NIO
22 April 2026
CBOR Encoded X.509 Certificates (C509 Certificates)
draft-ietf-cose-cbor-encoded-cert-18
Abstract
This document specifies a CBOR encoding of X.509 certificates. The
resulting certificates are called C509 certificates. The CBOR
encoding supports a large subset of RFC 5280, common certificate
profiles and is extensible.
Two types of C509 certificates are defined. One type is an
invertible CBOR re-encoding of DER-encoded X.509 certificates with
the signature field copied from the DER encoding. The other type is
identical except that the signature is over the CBOR encoding instead
of the DER encoding, avoiding the use of ASN.1. Both types of
certificates have the same semantics as X.509 and the same reduced
size compared to X.509.
The document also specifies CBOR encoded data structures for
certificate (signing) requests and certification request templates,
new COSE headers, as well as a TLS certificate type and a file format
for C509. This document updates RFC 6698; the TLSA selectors
registry is extended to include C509 certificates.
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-ietf-cose-cbor-encoded-cert/.
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Discussion of this document takes place on the CBOR Object Signing
and Encryption 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/.
Source for this draft and an issue tracker can be found at
https://github.com/cose-wg/CBOR-certificates.
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
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Internet-Drafts are draft documents valid for a maximum of six months
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This Internet-Draft will expire on 24 October 2026.
Copyright Notice
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document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Notational Conventions . . . . . . . . . . . . . . . . . . . 6
3. C509 Certificate . . . . . . . . . . . . . . . . . . . . . . 6
3.1. Message Fields . . . . . . . . . . . . . . . . . . . . . 7
3.2. Encoding of subjectPublicKey and issuerSignatureValue . . 12
3.3. Encoding of Extensions . . . . . . . . . . . . . . . . . 13
3.4. C509 COSE Header Parameters . . . . . . . . . . . . . . . 20
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3.5. C509 COSE Header Algorithm Parameters . . . . . . . . . . 21
3.6. Private Key Structures . . . . . . . . . . . . . . . . . 22
3.7. Deterministic Encoding . . . . . . . . . . . . . . . . . 23
3.8. C509 Name in TLS and DTLS . . . . . . . . . . . . . . . . 24
4. C509 Certification Request . . . . . . . . . . . . . . . . . 24
4.1. Certification Request Types . . . . . . . . . . . . . . . 25
4.2. Subject Signature Algorithm . . . . . . . . . . . . . . . 26
4.3. Certification Request Attributes . . . . . . . . . . . . 27
4.4. Certification Request Template . . . . . . . . . . . . . 27
5. C509 Processing and Certificate Issuance . . . . . . . . . . 29
6. Operational Considerations . . . . . . . . . . . . . . . . . 30
6.1. Legacy Considerations . . . . . . . . . . . . . . . . . . 30
6.2. Expected Certificate Sizes . . . . . . . . . . . . . . . 31
7. Security Considerations . . . . . . . . . . . . . . . . . . . 32
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 33
8.1. Designated Expert Guidance . . . . . . . . . . . . . . . 33
8.2. C509 Certificate Types Registry . . . . . . . . . . . . . 34
8.3. C509 Certification Request Types Registry . . . . . . . . 34
8.4. C509 Private Key Types Registry . . . . . . . . . . . . . 35
8.5. C509 Certification Request Templates Types Registry . . . 35
8.6. C509 RDN Attributes Registry . . . . . . . . . . . . . . 36
8.7. C509 CR Attributes Registry . . . . . . . . . . . . . . . 40
8.8. C509 Extensions Registry . . . . . . . . . . . . . . . . 41
8.9. C509 Certificate Policies Registry . . . . . . . . . . . 45
8.10. C509 Policies Qualifiers Registry . . . . . . . . . . . . 49
8.11. C509 Information Access Registry . . . . . . . . . . . . 49
8.12. C509 Extended Key Usages Registry . . . . . . . . . . . . 51
8.13. C509 General Names Registry . . . . . . . . . . . . . . . 53
8.14. C509 Signature Algorithms Registry . . . . . . . . . . . 55
8.15. C509 Public Key Algorithms Registry . . . . . . . . . . . 59
8.16. COSE Header Parameters Registry . . . . . . . . . . . . . 62
8.17. COSE Header Algorithm Parameters Registry . . . . . . . . 62
8.18. Media Type Application Registry . . . . . . . . . . . . . 62
8.19. CoAP Content-Formats Registry . . . . . . . . . . . . . . 69
8.20. TLS Certificate Types Registry . . . . . . . . . . . . . 70
8.21. TLSA Selectors Registry . . . . . . . . . . . . . . . . . 71
8.22. EDHOC Authentication Credential Types Registry . . . . . 71
8.23. Relative Distinguished Name Attribute . . . . . . . . . . 71
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 72
9.1. Normative References . . . . . . . . . . . . . . . . . . 72
9.2. Informative References . . . . . . . . . . . . . . . . . 76
Appendix A. C509 Certificate Examples . . . . . . . . . . . . . 79
A.1. Example: RFC 7925 profiled X.509 Certificate . . . . . . 79
A.2. Example: IEEE 802.1AR profiled X.509 Certificate . . . . 85
A.3. Example: CAB Baseline ECDSA HTTPS X.509 Certificate . . . 89
A.4. Example: CAB Baseline RSA HTTPS X.509 Certificate . . . . 91
A.5. Example: Certificate with Extensions IPAddrBlocks and
IPAddrBlocksV2 . . . . . . . . . . . . . . . . . . . . . 94
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Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 98
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 98
1. Introduction
One of the challenges with deploying a Public Key Infrastructure
(PKI) for the Internet of Things (IoT) is the size and parsing of
X.509 public key certificates [RFC5280], since those are not
optimized for constrained environments [RFC7228]. Large certificate
chains are also problematic in non-constrained protocols such as EAP-
TLS [RFC9190] [RFC9191] where authenticators typically drop an EAP
session after only 40–50 round-trips, QUIC [RFC9000] where the
latency increases significantly unless the server sends less than
three times as many bytes as received prior to validating the client
address, and Resource Public Key Infrastructure (RPKI) [RFC6487]
where a single certificate can be very large. More compact
certificate representations are, therefore, desirable in many use
cases.
X.509 certificates are defined with Abstract Syntax Notation One
(ASN.1) and encoded using the Distinguished Encoding Rules (DER)
[X.690]. This document specifies an alternative encoding of X.509
certificates, using the Concise Binary Object Representation (CBOR)
[RFC8949], initially proposed in [X.509-IoT]. The use of a more
compact encoding reduces the certificate size, which has known
performance benefits in terms of decreased communication overhead,
power consumption, latency, storage, etc. The re-encoding of X.509
is called C509 and the resulting certificates are termed C509
certificates. C509 is not a general CBOR encoding for ASN.1 data
structures.
CBOR is a data format designed for small code size and small message
size to support systems with very limited memory, processor power,
and instruction sets. CBOR builds on the JSON data model but extends
it by, e.g., encoding binary data directly without base64 conversion.
In addition to the binary CBOR encoding, CBOR also has a diagnostic
notation that is readable and editable by humans, simplifying
development and debugging. The Concise Data Definition Language
(CDDL) [RFC8610] provides a way to express structures for protocol
messages and APIs that use CBOR. [RFC8610] also extends the
diagnostic notation. For a complete specification and examples, see
[RFC8949], [RFC8610], and [RFC8742]. Implementors can get familiar
with CBOR by using the CBOR playground [CborMe].
The C509 encoding supports a large subset of [RFC5280] and all
certificates compatible with the [RFC7925], IEEE 802.1AR (DevID)
[IEEE-802.1AR], CAB Baseline [CAB-TLS], [CAB-Code], RPKI [RFC6487],
Wi-SUN [Wi-SUN], and eUICC [GSMA-eUICC] profiled X.509 certificates,
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and is designed to render a compact encoding of certificates used in
constrained environments. This document does not specify a
certificate profile.
CAB Baseline Requirements [CAB-TLS], [RFC7925], [IEEE-802.1AR], and
CNSA 1.0 [RFC8603] specify certificate profiles which can be applied
to certificate-based authentication with, e.g., TLS [RFC8446], QUIC
[RFC9000], DTLS [RFC9147], COSE [RFC9052], EDHOC [RFC9528], or
Compact TLS 1.3 [I-D.ietf-tls-ctls]. [RFC7925], RFC7925bis
[I-D.ietf-uta-tls13-iot-profile], and IEEE 802.1AR [IEEE-802.1AR]
specifically target IoT deployments.
At the time of publishing there are several implementations of C509
targeting, e.g., in-vehicle and vehicle-to-cloud communication,
Uncrewed Aircraft Systems (UAS), and Global Navigation Satellite
System (GNSS). When used to re-encode DER-encoded X.509
certificates, the CBOR encoding can reduce the size of [RFC7925]-
profiled certificates by over 50%, see Appendix A.
C509 is designed to be extensible to additional features of X.509,
for example, support for new algorithms, including new Post-Quantum
(PQ) algorithms, which can be registered in the IANA registry as they
become specified, see Section 8.14.
This document defines two types of C509 using the same CBOR encoding
and differing only in what is being signed:
1. An invertible CBOR re-encoding of DER-encoded X.509 certificates
[RFC5280], which can be reversed to obtain the original DER-
encoded X.509 certificate. Due to the widespread deployment of
X.509, it is necessary to allow backward compatibility.
2. Natively signed C509 certificates, where the signature is
calculated over the CBOR encoding instead of over the DER
encoding. This removes the need for ASN.1 and DER parsing and
the associated complexity but they are not backwards compatible
with implementations requiring DER-encoded X.509.
Natively signed C509 certificates can be applied in devices that are
only required to authenticate to natively signed C509 certificate
compatible servers, which is not a major restriction for many IoT
deployments where the parties issuing and verifying certificates can
be a restricted ecosystem.
This document also specifies C509 Certification Requests, see
Section 4; COSE headers for use of the C509 certificates with COSE,
see Section 8.16; a TLS certificate type for use of the C509
certificates with TLS and QUIC (with or without additional TLS
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certificate compression), see Section 8.20; and a C509 file format.
The TLSA selectors registry is extended to include C509 certificates,
thus this document updates [RFC6698].
2. Notational Conventions
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 specification makes use of the terminology in [RFC2986],
[RFC5280], [RFC7228], [RFC8610], and [RFC8949]. When referring to
CBOR, this specification always refers to Deterministically Encoded
CBOR as specified in Sections 4.2.1 and 4.2.2 of [RFC8949].
3. C509 Certificate
This section specifies the content and encoding for C509
certificates, with the overall objective to produce a very compact
representation supporting large parts of [RFC5280], and everything in
[RFC7925], [IEEE-802.1AR], RPKI [RFC6487], GSMA eUICC [GSMA-eUICC],
and CAB Baseline [CAB-TLS] [CAB-Code].
In the CBOR encoding, static fields are elided, elliptic curve points
and time values are compressed, OID are replaced with short integers
or complemented with CBOR OID encoding [RFC9090], and redundant
encoding is removed. Combining these different components reduces
the certificate size significantly, which is not possible with
general purpose compression algorithms, see Figure 5.
The C509 certificate can be either a CBOR re-encoding of a DER-
encoded X.509 certificate, in which case the signature is calculated
on the DER-encoded ASN.1 data in the X.509 certificate, or a natively
signed C509 certificate, in which case the signature is calculated
directly on the CBOR encoded data. In both cases the certificate
content is adhering to the restrictions given by [RFC5280]. The re-
encoding is known to work with DER-encoded certificates but might
work with other canonical encodings. The re-encoding does not work
for BER encoded certificates.
In the encoding described below, the elements in arrays are always
encoded in the same order as elements of the corresponding SEQUENCE
or SET in the DER encoding.
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3.1. Message Fields
The X.509 fields and their CBOR encodings are described in this
section, and used in the definition of C509 certificates, see
Figure 1. While much of [RFC5280] encodings used in practice is
supported, there are a few instances indicated with "not supported"
where no alternative is provided and hence no C509 encoding can be
generated.
The following Concise Data Definition Language (CDDL) defines the
CBOR array C509Certificate and the CBOR Sequence [RFC8742]
TBSCertificate. The member names therefore only have documentary
value. Applications not requiring a CBOR item MAY represent C509
certificates with the CBOR sequence ~C509Certificate (unwrapped
C509Certificate). Examples are given in the appendices, e.g.,
Appendix A.1.
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C509Certificate = [
TBSCertificate,
issuerSignatureValue : any,
]
; The elements of the following group are used in a CBOR Sequence:
TBSCertificate = (
c509CertificateType: int,
certificateSerialNumber: CertificateSerialNumber,
issuerSignatureAlgorithm: AlgorithmIdentifier,
issuer: Name / null,
validityNotBefore: ~time,
validityNotAfter: ~time / null,
subject: Name,
subjectPublicKeyAlgorithm: AlgorithmIdentifier,
subjectPublicKey: Defined,
extensions: Extensions,
)
CertificateSerialNumber = ~biguint
Name = [ * RDNAttribute ] / SpecialText
RDNAttribute = (
( attributeType: int, attributeValue: SpecialText ) //
( attributeType: ~oid, attributeValue: bytes )
)
AlgorithmIdentifier = int / ~oid /
[ algorithm: ~oid, parameters: bytes ]
Extensions = [ * Extension ] / int
Extension = (
( extensionID: int, extensionValue: Defined ) //
( extensionID: ~oid, extensionValue: bytes / [ bytes ] )
)
SpecialText = text / bytes / tag
Defined = any .ne undefined
tag = #6
Figure 1: CDDL for C509Certificate.
C509 certificates are defined in terms of DER-encoded X.509
certificates [RFC5280] as detailed in the following subsections.
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3.1.1. version
The 'version' field is encoded in the 'c509CertificateType' CBOR int.
The field 'c509CertificateType' also indicates the type of the C509
certificate. Two types are defined in this document: natively signed
C509 certificates, following X.509 v3 (c509CertificateType = 2); and
CBOR re-encoded X.509 v3 DER certificate (c509CertificateType = 3),
see Section 8.2. The number of elements in TBSCertificate is fixed
and determined by the type. Additional types may be added in the
future.
3.1.2. serialNumber
The 'serialNumber' INTEGER value field is encoded as the unwrapped
CBOR unsigned bignum (~biguint) 'certificateSerialNumber'. Any
leading 0x00 byte (to indicate that the number is not negative) is
therefore omitted.
3.1.3. signature
The 'signature' field, containing the signature algorithm including
parameters, is encoded as a CBOR int (see Section 8.14) or as an
array with an unwrapped CBOR OID tag [RFC9090] optionally followed by
the parameters encoded as a CBOR byte string.
3.1.4. issuer
In the general case, the sequence of 'RDNAttribute' is encoded as a
CBOR array consisting of RDNAttribute elements.
RelativeDistinguishedName with more than one AttributeTypeAndValue is
not supported. Each RDNAttribute is CBOR encoded as (type, value)
either as a (int, SpecialText) pair, or a (~oid, bytes) tuple.
In the former case, the absolute value of the int encodes the
attribute type (see Figure 11) and the sign is used to represent the
character string type in the X.509 certificate; positive for
utf8String, negative for printableString. Attribute values which are
always of type IA5String are unambiguously represented using a non-
negative int. Examples include emailAddress and domainComponent (see
[RFC5280]). In CBOR, all text strings are UTF-8 encoded and in
natively signed C509 certificates all CBOR ints SHALL be non-
negative. Text strings SHALL still adhere to any [RFC5280]
restrictions. serialNumber SHALL only contain the 74-character subset
of ASCII allowed by printableString and countryName SHALL have length
2. CBOR encoding is allowed for IA5String (if this is the only
allowed type, e.g., emailAddress), printableString and utf8String,
whereas the string types teletexString, universalString, and
bmpString are not supported.
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The text strings are further optimized as follows:
* If the text string has an even length ≥ 2 and contains only the
symbols '0'–'9' or 'a'–'f', it is encoded as a CBOR byte string.
* If the text string contains an EUI-64 of the form "HH-HH-HH-HH-HH-
HH-HH-HH" where each 'H' is one of the symbols '0'-'9' or 'A'-'F',
it is encoded as a CBOR tagged MAC address using the CBOR tag 48,
see Section 2.4 of [RFC9542]. If of the form "HH-HH-HH-FF-FE-HH-
HH-HH", it is encoded as a 48-bit MAC address, otherwise as a
64-bit MAC address. See example in Appendix A.1.
* Otherwise, it is encoded as a CBOR text string.
The final encoding of the extension value may therefore be text,
bytes, or tag, i.e., SpecialText. If Name contains a single 'common
name' attribute with attributeType = +1, it is for compactness
encoded as just the SpecialText containing the single attribute
value.
In natively signed C509 certificates, bytes and tag 48 do not
correspond to any predefined text string encoding and may also be
used for other attribute types.
If the 'issuer' field is identical to the 'subject' field, e.g., in
case of self-signed certificates, then the 'issuer' field MUST be
encoded as the CBOR simple value null (0xf6).
3.1.5. validity
The 'notBefore' and 'notAfter' fields are encoded as unwrapped CBOR
epoch-based date/time (~time) where the tag content is an unsigned
integer. In POSIX time, leap seconds are ignored, with a leap second
having the same POSIX time as the second before it. Compression of
X.509 certificates with the time 23:59:60 UTC is therefore not
supported. Note that RFC 5280 mandates encoding of dates through the
year 2049 as UTCTime, and later dates as GeneralizedTime. The value
"99991231235959Z" (no expiration date) is encoded as the CBOR simple
value null.
3.1.6. subject
The 'subject' field is encoded exactly like issuer, except that the
CBOR simple value is not a valid value.
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3.1.7. subjectPublicKeyInfo
The 'AlgorithmIdentifier' field including parameters is encoded as
the CBOR int 'subjectPublicKeyAlgorithm' (see Section 8.15) or as an
array with an unwrapped CBOR OID tag [RFC9090] optionally followed by
the parameters encoded as a CBOR byte string.
In general, the 'subjectPublicKey' BIT STRING value field is encoded
as a CBOR byte string, but may be encoded as a CBOR item of any type
except undefined (see Section 4.4). This specification assumes the
BIT STRING has zero unused bits, and the unused bits byte is omitted.
For rsaEncryption and id-ecPublicKey, the encoding of
subjectPublicKey is further optimized as described in Section 3.2.
3.1.8. issuerUniqueID
Not supported.
3.1.9. subjectUniqueID
Not supported.
3.1.10. extensions
The 'extensions' field is encoded either as a CBOR array or as a CBOR
int. An omitted 'extensions' field is encoded as an empty CBOR
array.
Each 'extensionID' in the CBOR array is encoded either as a CBOR int
(see Section 8.8) or as an unwrapped CBOR OID tag [RFC9090].
* If 'extensionID' is encoded as a CBOR int, it is followed by a
CBOR item of any type except undefined (see Section 4.4), and the
sign of the int is used to encode if the extension is critical:
Critical extensions are encoded with a negative sign and non-
critical extensions are encoded with a positive sign. If the CBOR
array contains exactly two ints and the absolute value of the
first int is 2 (corresponding to keyUsage, see Section 3.3), the
CBOR array is omitted and the extensions is encoded as a single
CBOR int with the absolute value of the second int and the sign of
the first int.
* If extensionID is encoded as an unwrapped CBOR OID tag, it is
followed by the DER-encoded extnValue encoded in the following
way:
- if the extension is non-critical, the extnValue OCTET STRING
value field is encoded as a CBOR byte string;
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- if the extension is critical, the extnValue OCTET STRING value
field is encoded as a CBOR byte string and further wrapped in a
CBOR array consisting of only this element.
The processing of critical and non-critical extensions is specified
in Section 4.2 of [RFC5280].
The currently defined extension values for which there is CBOR int
encoded 'extensionID' are specified in Section 3.3. The extensions
mandated to be supported by [RFC7925] and [IEEE-802.1AR] are given
special treatment.
More details about extensions in Section 3.3.
3.1.11. signatureAlgorithm
The 'signatureAlgorithm' field is always the same as the 'signature'
field and therefore omitted from the CBOR encoding.
3.1.12. signatureValue
In general, the 'signatureValue' BIT STRING value field is encoded as
the CBOR byte string issuerSignatureValue. This specification
assumes that the BIT STRING has zero unused bits, and the unused bits
byte is omitted. For natively signed C509 certificates, the
signatureValue is calculated over the CBOR sequence TBSCertificate.
For ECDSA, the encoding of issuerSignatureValue is further optimized
as described in Section 3.2
3.2. Encoding of subjectPublicKey and issuerSignatureValue
3.2.1. Encoding of subjectPublicKey
For RSA public keys (rsaEncryption), the SEQUENCE and INTEGER type
and length fields are omitted, and the two INTEGER value fields
(modulus, exponent) are encoded as an array of two unwrapped CBOR
unsigned bignum (~biguint), i.e., [ modulus : ~biguint, exponent :
~biguint ]. If the exponent is 65537, the array and the exponent are
omitted and subjectPublicKey consists of only the modulus encoded as
an unwrapped CBOR unsigned bignum (~biguint).
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For elliptic curve public keys in Weierstrass form (id-ecPublicKey),
keys may be point compressed as defined in Section 2.3.3 of [SECG].
Native C509 certificates with Weierstrass form keys use the octets
0x02, 0x03, and 0x04 as defined in [SECG]. If a DER-encoded
certificate with an uncompressed public key of type id-ecPublicKey is
CBOR encoded with point compression, then the octet 0xfe is used
instead of 0x02 to represent an even y-coordinate, and the octet 0xfd
is used instead of 0x03 to represent an odd y-coordinate.
3.2.2. Encoding of issuerSignatureValue
For ECDSA signatures, the SEQUENCE and INTEGER type and length fields
as well as any leading 0x00 byte (to indicate that the number is not
negative) are omitted. Each of the two INTEGER value fields are then
padded with leading zeroes to the same fixed length, given by the
number of bytes needed to represent the order n of the cyclic
subgroup used with the algorithm. For example, for P-256, the number
of bytes for each integer is 32. The resulting byte string is
encoded as a CBOR byte string.
3.3. Encoding of Extensions
The 'extensions' field is encoded as specified in Section 3.1.10 with
further details provided in this section.
For some extensions, the CBOR int encoded extensionID is only
supported for commonly used values of the extension. In case of
extension values for which the CBOR int encoded extensionID is not
supported, the extension MUST be encoded using the unwrapped CBOR OID
tag encoded extensionID.
A note on extensionID naming: in existing OID databases, most IDs can
be found in versions with and without an 'id-pe' or 'id-ce' prefix.
We have excluded the prefix for the commonly used extensions defined
in [RFC5280] and included them for extensions defined elsewhere.
CBOR encoding of the following extension values is fully supported:
* Subject Key Identifier (subjectKeyIdentifier). In natively signed
certificates, KeyIdentifier can, for example, be composed of the
leftmost 160-bits of the SHA-256 hash of the CBOR encoded
subjectPublicKey. Other methods of generating unique numbers can
be used. The extensionValue is encoded as follows:
KeyIdentifier = bytes
SubjectKeyIdentifier = KeyIdentifier
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* Key Usage (keyUsage). The 'KeyUsage' BIT STRING is interpreted as
an unsigned integer in network byte order and encoded as a CBOR
int. See Section 3.1.10 for special encoding in case keyUsage is
the only extension present.
KeyUsage = uint
* Policy Mappings (policyMappings). extensionValue is encoded as
follows:
PolicyMappings = [
+ (issuerDomainPolicy: int/~oid, subjectDomainPolicy: int/~oid)
]
* Basic Constraints (basicConstraints). If 'cA' = false then
extensionValue = -2, if 'cA' = true and 'pathLenConstraint' is not
present then extensionValue = -1, and if 'cA' = true and
'pathLenConstraint' is present then extensionValue =
pathLenConstraint.
BasicConstraints = int
* Policy Constraints (policyConstraints). extensionValue is encoded
as follows:
PolicyConstraints = [
requireExplicitPolicy: uint / null,
inhibitPolicyMapping: uint / null,
]
* Extended Key Usage (extKeyUsage). extensionValue is encoded as an
array of CBOR ints (see Section 8.12), or unwrapped CBOR OID tags
[RFC9090], where each int or OID encodes a key usage purpose. If
the array contains a single KeyPurposeId, the array is omitted.
KeyPurposeId = int / ~oid
ExtKeyUsageSyntax = [ 2* KeyPurposeId ] / KeyPurposeId
* Inhibit anyPolicy (inhibitAnyPolicy). extensionValue is encoded as
follows:
InhibitAnyPolicy = uint
CBOR encoding of the following extension values are partly supported:
* Subject Alternative Name (subjectAltName). If the subject
alternative name only contains general names registered in
Section 8.13 the extension value can be CBOR encoded.
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extensionValue is encoded as an array of (int, any) pairs where
each pair encodes a general name (see Section 8.13). If
subjectAltName contains exactly one dNSName, the array and the int
are omitted and extensionValue is the dNSName encoded as a CBOR
text string. In addition to the general names defined in
[RFC5280], the otherName with type-id id-on-hardwareModuleName,
id-on-SmtpUTF8Mailbox and id-on-MACAddress have been given their
own ints; such otherName are encoded as follows:
- For id-on-hardwareModuleName, the value is a CBOR array [
hwType: ~oid, hwSerialNum: bytes ] as specified in [RFC4108].
- For id-on-SmtpUTF8Mailbox, the value is a CBOR text as
specified in [RFC8398].
- For id-on-MACAddress, the value is a CBOR byte string
containing 6 octets for EUI-48 and 8 octets for EUI-64 as
specified in [I-D.ietf-lamps-macaddress-on].
GeneralName = ( GeneralNameType : int, GeneralNameValue : any )
GeneralNames = [ + GeneralName ]
SubjectAltName = GeneralNames / text
* Issuer Alternative Name (issuerAltName). extensionValue is encoded
exactly like subjectAltName.
IssuerAltName = GeneralNames / text
* CRL Distribution Points (cRLDistributionPoints). If all
DistributionPoint elements contain the distributionPoint with
fullName choice of uniformResourceIdentifier, optional reasons,
and optional cRLIssuer with one directoryName, the extension value
can be CBOR encoded. The 'reasons' BIT STRING is interpreted as
an unsigned integer in network byte order and encoded as a CBOR
uint. If the CRLDistributionPoints consists of only one
DistributionPointName, which in turn has only the fullName field
of type CBOR text, it shall be encoded as CBOR text, otherwise as
CBOR array.
DistributionPointName = [
fullName [ 2 * text ] / text,
reasons uint / null,
cRLIssuer Name / null,
]
CRLDistributionPoints = [ + DistributionPointName ] / text
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* Freshest CRL (freshestCRL). extensionValue is encoded exactly like
cRLDistributionPoints.
FreshestCRL = CRLDistributionPoints
* Authority Information Access (authorityInfoAccess). If all the
GeneralNames in authorityInfoAccess are of type
uniformResourceIdentifier, the extension value can be CBOR
encoded. Each accessMethod is encoded as a CBOR int (see
Section 8.11) or an unwrapped CBOR OID tag [RFC9090]. The
uniformResourceIdentifiers are encoded as CBOR text strings.
AccessDescription = ( accessMethod: int / ~oid , uri: text )
AuthorityInfoAccessSyntax = [ + AccessDescription ]
* Subject Information Access (subjectInfoAccess). Encoded exactly
like authorityInfoAccess.
SubjectInfoAccessSyntax = AuthorityInfoAccessSyntax
* Authority Key Identifier (authorityKeyIdentifier). If the
authority key identifier contains all of keyIdentifier,
certIssuer, and certSerialNumber or if only keyIdentifier is
present the extension value can be CBOR encoded. If all three are
present a CBOR array is used, if only keyIdentifier is present,
the array is omitted:
KeyIdentifierArray = [
keyIdentifier: KeyIdentifier,
authorityCertIssuer: GeneralNames,
authorityCertSerialNumber: CertificateSerialNumber
]
AuthorityKeyIdentifier = KeyIdentifierArray / KeyIdentifier
* Certificate Policies (certificatePolicies). If noticeRef is not
used and any explicitText are encoded as UTF8String, the extension
value can be CBOR encoded. OIDs registered in Section 8.9 are
encoded as an int. The policyQualifierId is encoded as an CBOR
int (see Section 8.10) or an unwrapped CBOR OID tag [RFC9090].
PolicyIdentifier = int / ~oid
PolicyQualifierInfo = (
policyQualifierId: int / ~oid,
qualifier: text,
)
CertificatePolicies = [
+ ( PolicyIdentifier, [ * PolicyQualifierInfo ] )
]
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* Name Constraints (nameConstraints). If the name constraints only
contain general names registered in Section 8.13 the extension
value can be CBOR encoded. C509 uses the same additions and
restrictions as defined in Section 2.2 of [RFC9549]. Note that
the minimum and maximum fields are not used and therefore omitted.
For IPv4 addresses, the iPAddress field MUST contain five octets
and for IPv6 addresses, the field MUST contain 17 octets, where
the last octet indicates the number of bits in the prefix. As an
example, the address block 192.0.2.0/24 is encoded as C0 00 02 00
18 instead of C0 00 02 00 FF FF FF 00 as in the DER encoding.
GeneralSubtrees = [ + GeneralName ]
NameConstraints = [
permittedSubtrees: GeneralSubtrees / null,
excludedSubtrees: GeneralSubtrees / null,
]
* Subject Directory Attributes (subjectDirectoryAttributes).
Encoded as attributes in issuer and subject with the difference
that there can be more than one attributeValue.
RDNAttributes = (
( attributeType: int, attributeValue: [ + SpecialText] ) //
( attributeType: ~oid, attributeValue: [+ bytes] )
)
SubjectDirectoryAttributes = [ + RDNAttributes ]
* AS Identifiers (id-pe-autonomousSysIds). The X.509 extension AS
Identifiers is specified in [RFC3779]. If rdi is not present, the
extension value can be CBOR encoded. Each ASId is encoded as a
CBOR uint. With the exception of the first ASId, the ASid is
encoded as the difference to the previous ASid.
ASIdOrRange = uint / [min:uint, max:uint]
ASIdentifiers = [ + ASIdOrRange ] / null
* AS Identifiers v2 (id-pe-autonomousSysIds-v2). The X.509
extension AS Identifiers v2 is specified in [RFC8360]. The
extension value is encoded exactly like in the extension "AS
Identifiers".
* IPAddrBlocks (id-pe-ipAddrBlocks). The X.509 extension
IPAddrBlocks is specified in [RFC3779]. The ASN.1 BIT STRING
value of IPAddress is converted to a byte sequence defined as:
unusedBits || value
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where unusedBits is a single octet indicating the number of unused
bits in the final octet of the BIT STRING, and value is the
sequence of octets containing the BIT STRING value. This byte
sequence preserves the exact information contained in the ASN.1
BIT STRING.
For each IPAddressFamily, the representation is selected as
follows:
- If inherit is present, null SHALL be used.
- Otherwise, if the byte sequence of any IPAddress (including
addressPrefix, and the min and max fields of addressRange)
exceeds 8 octets in length, the IPAddressChoice representation
SHALL be used.
- Otherwise, the IntIPAddressChoice representation SHALL be used.
For IntIPAddressChoice, IntAddressPrefix and the min and max
values of IntAddressRange SHALL be encoded as big-endian integers
representing the following byte sequence:
(unusedBits + 1) || value
The first byte is encoded as (unusedBits + 1) instead of
unusedBits in order to guarantee a non-zero value. With the
exception of the first IPAddress, each subsequent IPAddress SHALL
be encoded as a CBOR integer representing the difference from the
previous IPAddress.
As specified in [RFC3779], the IPAddressFamily element contains an
Address Family Identifier (AFI) and, optionally, a Subsequent
Address Family Identifier (SAFI). AFIs and SAFIs are defined in
[IANA-AFI] and [IANA-SAFI], respectively. The limitations
specified in [RFC3779] apply here as well.
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IntAddressPrefix = int
IntAddressRange = [ min: int, max: int ]
IntIPAddressOrRange = IntAddressPrefix / IntAddressRange
IntIPAddressChoice = [ + IntIPAddressOrRange ]
AddressPrefix = bytes
AddressRange = [ min: bytes, max: bytes ]
IPAddressOrRange = AddressPrefix / AddressRange
IPAddressChoice = [ + IPAddressOrRange ]
IPAddressFamily = (AFI: uint, SAFI: uint / null,
IntIPAddressChoice / IPAddressChoice / null)
IPAddrBlocks = [ + IPAddressFamily ]
* IPAddrBlocks v2 (id-pe-ipAddrBlocks-v2). The X.509 extension
IPAddrBlocks v2 is specified in [RFC8360]. The extension value is
encoded exactly like in the extension "IPAddrBlocks".
* OCSP No Check (id-pkix-ocsp-nocheck). If the extension value is
NULL, it can be CBOR encoded. The CBOR encoded extensionValue is
the value null.
* Precertificate Signing Certificate. The CBOR encoded
extensionValue is the value null.
* TLS Features (id-pe-tlsfeature). The extensionValue is encoded as
an array of integers, where each integer represents a TLS
extension.
TLSFeatures = [* feature: uint]
3.3.1. Example Encoding of Extensions
The examples below use values from Section 8.8, Section 8.12, and
Section 8.13:
* A critical basicConstraints ('cA' = true) without
pathLenConstraint is encoded as the two CBOR ints -4, -1.
* A non-critical keyUsage with digitalSignature (0), nonRepudiation
(1), keyEncipherment (2) and keyAgreement (4) asserted is encoded
as the two CBOR ints 2, 23 (2^0 + 2^1 + 2^2 + 2^4 = 23).
* A non-critical extKeyUsage containing id-kp-codeSigning and id-kp-
OCSPSigning is encoded as the CBOR int 8 followed by the CBOR
array [ 3, 9 ].
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* A non-critical subjectAltName containing only the dNSName
example.com is encoded as the CBOR int 3 followed by the CBOR text
string "example.com".
Thus, the extension field of a certificate containing all of the
above extensions in the given order would be encoded as the CBOR
array [ -4, -1, 2, 23, 8, [ 3, 9 ], 3, "example.com" ].
3.4. C509 COSE Header Parameters
The formatting and processing for c5b, c5c, c5t, and c5u, defined in
Table 1 below, are similar to x5bag, x5chain, x5t, x5u defined in
[RFC9360] except that the certificates are C509 instead of DER-
encoded X.509 and use a COSE_C509 structure instead of COSE_X509.
The COSE_C509 structure used in c5b, c5c, and c5u is defined as:
COSE_C509 = C509CertData / [ 2* C509CertData ]
C509CertData = bytes .cborseq C509Certificate
C509CertData thus includes the unwrapped CBOR sequence,
~C509Certificate. The byte string encoding includes the length of
each certificate which simplifies parsing. See Appendix A.1.5 for an
example.
The COSE_C509 item has media type application/cose-c509-cert, see
Section 8.18.1. Different CoAP Content-Formats are defined depending
on "usage" = "chain" or not, see Section 8.19. Stored file formats
are defined for the cases with/without ("usage" = "chain") with
"magic numbers" TBD8/TBD6 using the reserved CBOR tag 55799 and the
corresponding Content-Formats TBD15/TBD3, enveloped as described in
Section 2.2 of [RFC9277].
The value type of c5t is the COSE_CertHash structure defined in
[RFC9360], which contains the hash value of the C509 certificate
calculated over ~C509Certificate. Thus C509CertData contains all
data necessary to calculate the thumbprint c5t.
c5u provides an alternative way to identify an untrusted certificate
chain by reference with a URI [RFC3986], encoded as a CBOR text
string (media type application/cbor and CoAP Content-Format 60). The
referenced resource is a COSE_C509 item served with the application/
cose-c509-cert media type ("usage" = "chain"), as described above.
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As the contents of c5b, c5c, c5t, and c5u are untrusted input, the
header parameters can be in either the protected or unprotected
header bucket. The trust mechanism MUST process any certificates in
the c5b, c5c, and c5u parameters as untrusted input. The presence of
a self-signed certificate in the parameter MUST NOT cause the update
of the set of trust anchors without appropriate authorization.
+======+=======+===============+=============================+
| Name | Label | Value Type | Description |
+======+=======+===============+=============================+
| c5b | 24 | COSE_C509 | An unordered bag of C509 |
| | | | certificates |
+------+-------+---------------+-----------------------------+
| c5c | 25 | COSE_C509 | An ordered chain of C509 |
| | | | certificates |
+------+-------+---------------+-----------------------------+
| c5t | 22 | COSE_CertHash | Hash of a ~C509Certificate |
+------+-------+---------------+-----------------------------+
| c5u | 23 | uri | URI pointing to a COSE_C509 |
| | | | containing an ordered chain |
| | | | of certificates |
+------+-------+---------------+-----------------------------+
Table 1: C509 COSE Header Parameters
Note that certificates can also be identified with a 'kid' header
parameter by storing 'kid' and the associated bag or chain in a
dictionary.
3.5. C509 COSE Header Algorithm Parameters
This section defines the COSE header parameters used for identifying
or transporting the sender's key for static-static key agreement
algorithms corresponding to Section 3 of [RFC9360], see Table 2.
* c5c-sender contains the chain of certificates starting with the
sender's key exchange certificate. The structure is the same as
'c5c'.
* c5t-sender contains the hash value for the sender's key exchange
certificate. The structure is the same as 'c5t'.
* c5u-sender contains a URI for the sender's key exchange
certificate. The structure and processing are the same as 'c5u'.
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+======+==========+=============+===============+==================+
| Name|Algorithm | Label | Type | Description |
+======+==========+=============+===============+==================+
| c5c-|ECDH- | -30 | COSE_C509 | An ordered chain |
|sender|SS+HKDF- | (suggested) | | of C509 |
| |256, ECDH-| | | certificates |
| |SS+HKDF- | | | |
| |512, ECDH-| | | |
| |SS+A128KW,| | | |
| |ECDH- | | | |
| |SS+A192KW,| | | |
| |ECDH- | | | |
| |SS+A256KW | | | |
+------+----------+-------------+---------------+------------------+
| c5t-|ECDH- | -31 | COSE_CertHash | Hash of a |
|sender|SS+HKDF- | (suggested) | | ~C509Certificate |
| |256, ECDH-| | | |
| |SS+HKDF- | | | |
| |512, ECDH-| | | |
| |SS+A128KW,| | | |
| |ECDH- | | | |
| |SS+A192KW,| | | |
| |ECDH- | | | |
| |SS+A256KW | | | |
+------+----------+-------------+---------------+------------------+
| c5u-|ECDH- | -32 | uri | URI pointing to |
|sender|SS+HKDF- | (suggested) | | a COSE_C509 |
| |256, ECDH-| | | containing an |
| |SS+HKDF- | | | ordered chain of |
| |512, ECDH-| | | certificates |
| |SS+A128KW,| | | |
| |ECDH- | | | |
| |SS+A192KW,| | | |
| |ECDH- | | | |
| |SS+A256KW | | | |
+------+----------+-------------+---------------+------------------+
Table 2: Static ECDH Algorithm Values
3.6. Private Key Structures
Certificate management also makes use of data structures including
private keys, see, e.g., [RFC7468]. This section defines the
following CBOR encoded structures:
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C509PrivateKey = [
C509PrivateKeyType: int,
subjectPrivateKeyAlgorithm: AlgorithmIdentifier,
subjectPrivateKey: any,
]
The field 'C509PrivateKeyType' indicates the type of the C509 private
key. Different types of C509 Private Key Structures can be defined,
see Section 8.4. Currently, two types are defined. When
C509PrivateKeyType = 0, the subjectPrivateKey is the CBOR byte string
encoding of the PrivateKey OCTET STRING value field defined in
[RFC5958]. When C509PrivateKeyType = 1, the subjectPrivateKey is a
COSE_KEY structure containing a private key as defined in [RFC9052].
Note that COSE_KEY might not be possible to use with all algorithms
that have a C509 AlgorithmIdentifier defined.
The C509PrivateKey item is served with the application/cose-
c509-privkey media type, see Section 8.18.4, with corresponding CoAP
Content-Format defined in Section 8.19. A stored file format is
defined with "magic number" TBD12 using the reserved CBOR tag 55799
and the Content-Format TBD10, enveloped as described in Section 2.2
of [RFC9277].
C509PEM = [
C509PrivateKey,
COSE_C509 / null,
]
The C509PEM item is served with the application/cose-c509-pem media
type, see Section 8.18.5, with corresponding CoAP Content-Format
defined in Section 8.19. A stored file format is defined with "magic
number" TBD13 using the reserved CBOR tag 55799 and the Content-
Format TBD11, enveloped as described in Section 2.2 of [RFC9277].
3.7. Deterministic Encoding
In some use cases it is desirable to be able to specify a unique C509
representation of a given X.509 certificate.
While this specification requires the use of Deterministically
Encoded CBOR (see Section 2), it is still possible to represent
certain X.509 certificate fields in different ways. This is a
consequence of the extensibility of the C509 format where new
encodings can be defined, for example to optimize extensions for
which no special CBOR encoding have been previously defined.
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Where there is support for a specific and a generic CBOR encoding,
the specific CBOR encoding MUST be used. For example, when there is
support for specific CBOR encoding of an extension, as specified in
Section 3.3 and the C509 Extensions Registry, it MUST be used. In
particular, when there is support for a specific otherName encoding
(negative integer value in C509 General Names Registry) it MUST be
used.
Native C509 certificates MUST only use specific CBOR encoded fields.
However, when decoding a non-native C509 certificates, the decoder
may need to support, for example, (extensionID: ~oid, extensionValue:
bytes / [bytes])-encoding of an extension for which there is an
(extensionID:int, extensionValue:Defined)-encoding. One reason is
that the certificate was issued before the specific CBOR extension
was registered.
3.8. C509 Name in TLS and DTLS
In TLS and DTLS, the subject of trusted authory may be sent to the
peer to help it selecting the certificate chain, as in the
CertificateAuthoritiesExtension in [RFC8446], in the
certificate_authorities field of CertificateRequest in [RFC5246], or
in the TrustedAuthorities in [RFC6066]. For such usage in the TLS
and DTLS, the C509 name is wrapped in a distinguished name [X.501]
with exactly one RelativeDistinguishedName, which in turn contains
exactly one AttributeTypeAndValue with the attribute C509Name. The
attribute value is the raw byte string of the encoded C509 Name as in
Section 3.1.6.
The attribute for C509 Name has the following structure:
id-rdna-c509Name OBJECT IDENTIFIER ::= { 1 3 6 1 5 5 7 25 TBD30 }
c509Name ATTRIBUTE ::= {
WITH SYNTAX C509Name
SINGLE VALUE TRUE
ID id-rdna-c509Name }
C509Name ::= OCTET STRING
4. C509 Certification Request
This section defines the format of a C509 Certification Request based
on [RFC2986]. It reuses the formatting of C509 certificates defined
in Section 3. A Certification Request is commonly referred to as a
Certificate Signing Request (CSR).
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The CDDL for the C509 Certification Request is shown in Figure 2.
The fields have the same encoding as the corresponding fields of the
C509 Certificate, see Section 3.1.
C509CertificationRequest = [
TBSCertificationRequest,
subjectSignatureValue: any,
]
; The elements of the following group are used in a CBOR Sequence:
TBSCertificationRequest = (
c509CertificationRequestType: int,
subjectSignatureAlgorithm: AlgorithmIdentifier,
subject: Name,
subjectPublicKeyAlgorithm: AlgorithmIdentifier,
subjectPublicKey: Defined,
attributes: CRAttributes,
)
CRAttributes = [ * CRAttribute ]
CRAttribute = (( attributeType: int, attributeValue: Defined ) //
( attributeType: ~oid, attributeValue: bytes ))
Figure 2: CDDL for C509CertificationRequest.
After verifying the subjectSignatureValue, the Certification
Authority (CA) MAY transform the C509CertificationRequest into a
[RFC2986] CertificationRequestInfo for compatibility with existing
procedures and code.
The media type of C509CertificationRequest is application/cose-
c509-pkcs10, see Section 8.18.2, with corresponding CoAP Content-
Format defined in Section 8.19. The "magic number" TBD9 is defined
using the reserved CBOR tag 55799 and the Content-Format TBD4,
enveloped as described in Section 2.2 of [RFC9277].
4.1. Certification Request Types
Two types of C509 Certification Requests are defined, both using the
same CBOR encoding and differing only in what is being signed, see
Section 8.3. The C509 Certification Request can either be an
invertible CBOR re-encoding of a DER-encoded certification request
[RFC2986], or it can be natively signed where the signature is
calculated over the CBOR encoding instead of the DER encoding.
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* c509CertificationRequestType = 2. This type indicates that the
C509 Certification Request is natively signed, i.e., that
subjectSignatureValue contains the signature over the CBOR
Sequence TBSCertificationRequest, see Figure 2. This encoding
removes the need for ASN.1 and DER parsing, and re-encoding in the
requesting party.
* c509CertificationRequestType = 3. This type indicates that the
C509 Certification Request is a CBOR re-encoded [RFC2986]
certification request, as defined in Section 4. This encoding is
backwards compatible with legacy RFC 2986 certification requests,
and enables a reduced transport overhead.
The type of certificate issued after the request is decided by the
application. The default type of issued certificate in case of C509
is that c509CertificateType = c509CertificationRequestType.
An implementation MAY only support certain values of
c509CertificationRequestType.
4.2. Subject Signature Algorithm
subjectSignatureAlgorithm can be a signature algorithm or a non-
signature proof-of-possession algorithm, e.g., as defined in
[RFC6955]. In the case of [RFC6955], the signature is replaced by a
MAC and requires a public Diffie-Hellman key of the verifier
distributed out-of-band. Both signature algorithms and non-signature
proof-of-possession algorithms are listed in the C509 Signature
Algorithms Registry, see Section 8.14. The non-signature proof-of-
possession algorithms with SHA-2 and HMAC-SHA2 (see values 14-16 in
Section 8.14) require a signature value with syntax DhSigStatic
defined as follows:
DhSigStatic = MessageDigest / DhSigStaticType
MessageDigest = bytes
DhSigStaticType = [
issuer: Name,
serialNumber: CertificateSerialNumber
hashValue: MessageDigest
]
Note that a key agreement key pair may be used with a signature
algorithm in a certification request, see Appendix A.1.3.
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4.3. Certification Request Attributes
The 'attributes' field specifies the attributes contained in a
certification request. The 'attributes' field with no
GeneralAttribute SHALL be encoded as an empty CBOR array.
The remainder of this section specifies CBOR encoded attributes for
Certification Requests.
4.3.1. Extension Request
The X.509 attribute "Extension Request" is defined in [RFC2985]. The
'attributeValue' field has type Extensions as in Section 3.1. An
empty CBOR array indicates no extensions.
4.3.2. Challenge Password
The X.509 attribute "Challenge Password" is defined in [RFC2985].
The 'attributeValue' field has type ChallengePassword. A UTF8 String
is encoded as CBOR text, and a Printable String is tagged with number
121 (alternative 0 as defined in [IANA-CBOR-TAGS]). All other string
types are not supported. For certification request type 2, only UTF8
String is allowed.
ChallengePassword = text / #6.121(text)
4.3.3. Private Key Possession Statement
The X.509 attribute "Statement of Possession of a Private Key" is
defined in [RFC9883]. The 'attributeValue' field has type
PrivateKeyPossessionStatement.
PrivateKeyPossessionStatement = [
issuer: Name,
serialNumber: CertificateSerialNumber,
cert: C509Certificate / null,
]
4.4. Certification Request Template
Enrollment over Secure Transport (EST, [RFC7030]) defines, and
[I-D.ietf-lamps-rfc7030-csrattrs] clarifies, how an EST server can
specify what it expects the EST client to include in a subsequent
Certification Request. Alternatively to the unstructured mechanism
specified in [RFC7030], Appendix B of [RFC8295] describes an approach
using a Certification Request Template in response to a GET /csrattrs
request by the EST client. The EST server thus returns a
Certification Request-like object with various fields filled out, and
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other fields waiting to be filled in and a signature to be added by
the EST client.
The approach of [RFC8295] is also followed for C509. The
C509CertificationRequestTemplate is based on TBSCertificationRequest
of the C509CertificationRequest, see Figure 2, but excludes the
subjectSignatureValue field from the template since that needs no
further specification.
The C509 Certification Request Template is shown in Figure 3.
C509CertificationRequestTemplate = [
c509CertificationRequestTemplateType: int,
c509CertificationRequestType: [+ int] / undefined,
subjectSignatureAlgorithm: [+ AlgorithmIdentifier] / undefined,
subject: NameTemplate / undefined,
subjectPublicKeyAlgorithm: [+ AlgorithmIdentifier] / undefined,
subjectPublicKey: undefined,
extensionsRequest: ExtensionsTemplate / undefined,
]
NameTemplate = [ * RDNAttributeTemplate ]
RDNAttributeTemplate = (
( attributeType: uint, minOccurs: uint, maxOccurs: uint,
attributeValue: SpecialText / undefined ) //
( attributeType: ~oid, minOccurs: uint, maxOccurs: uint,
attributeValue: bytes / undefined )
)
ExtensionsTemplate = [ * ExtensionTemplate ]
ExtensionTemplate = (
( extensionID: uint, optional: bool, extensionValue: any ) //
( extensionID: ~oid, optional: bool,
extensionValue: bytes / undefined )
)
Figure 3: CDDL for C509CertificationRequestTemplate.
Except as specified in this section, the fields have the same
encoding as the corresponding fields of the TBSCertificationRequest,
see Figure 2. The specification of the template makes use of the
CBOR simple value undefined (0xf7) to indicate fields to fill in.
Consistent with this rule, note that the subjectPublicKey field
always has the value undefined in the template.
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Different types of Certification Request Templates can be defined
(see Section 8.5), distinguished by the
c509CertificationRequestTemplateType integer. Each type may have its
own CDDL structure.
The presence of a Defined (non-undefined) value in a
C509CertificationRequestTemplate indicates that the server expects
the client to use that value in the certification request. If
multiple AlgorithmIdentifier or c509CertificationRequestType values
are present, the server expects the client to select one of them for
use in the Certification Request. The presence of an undefined value
indicates that the client is expected to provide an appropriate value
for that field. For example, if the server includes a subjectAltName
with a GeneralNameType iPAddress and a GeneralNameValue empty byte
string, this means that the client SHOULD fill in a corresponding
GeneralNameValue.
For AttributeTemplate, the minOccurs and maxOccurs fields specify the
minimal and maximal occurrences of attributes of the given
attributeType; maximal shall not be less than minimal, and maximal
shall be positive. Negative attributeType is not allowed.
For ExtensionTemplate, the field "optional" specifies whether an
extension of the given extensionID is optional. Negative extensionID
is not allowed.
The media type of C509CertificationRequestTemplate is application/
cose-c509-crtemplate, see Section 8.18.3, with corresponding CoAP
Content-Format defined in Section 8.19. The "magic number" TBD18 is
defined using the reserved CBOR tag 55799 and the Content-Format
TBD19, enveloped as described in Section 2.2 of [RFC9277].
5. C509 Processing and Certificate Issuance
It is straightforward to integrate the C509 format into legacy X.509
processing during certificate issuance. C509 processing can be
performed as an isolated function of the CA, or as a separate
function trusted by the CA.
The Certification Request format defined in Section 4 follows the
PKCS#10 format to enable a direct mapping to the certification
request information, see Section 4.1 of [RFC2986]. The CA can make
use of a Certification Request Template defined in Section 4.4, for
simplified configuration.
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When a certification request is received, the CA, or function trusted
by the CA, needs to perform some limited C509 processing and verify
the proof-of-possession corresponding to the public key, before
normal certificate generation can take place.
In the reverse direction, in case c509CertificateType = 3 was
requested, a separate C509 processing function can perform the
conversion from a generated X.509 certificate to C509 as a bump-in-
the-wire. In case c509CertificateType = 2 was requested, the C509
processing needs to be performed before signing the certificate, in
which case a tighter integration with the CA may be needed.
6. Operational Considerations
6.1. Legacy Considerations
C509 certificates can be deployed with legacy X.509 certificates and
CA infrastructure. An existing CA can continue to use its existing
procedures and code for PKCS#10, and DER-encoded X.509 and only
implement C509 as a thin processing layer on top. When receiving a
C509 Certification Request, the CA transforms it into a DER-encoded
CertificationRequestInfo [RFC2986] and uses that with existing
processes and code to produce an RFC 5280 DER-encoded X.509
certificate. The DER-encoded X.509 is then transformed into a C509
certificate. At any later point, the C509 certificate can be used to
recreate the original X.509 data structure needed to verify the
signature.
For protocols like TLS/DTLS 1.2, where certificates are sent
unencrypted, the actual encoding and compression can be done at
different locations depending on the deployment setting. For
example, the mapping between C509 certificate and standard X.509
certificate can take place in a 6LoWPAN border gateway, which allows
the server side to stay unmodified. This case gives the advantage of
the low overhead of a C509 certificate over constrained wireless
links. The conversion to X.509 within a constrained IoT device will
incur a computational overhead. However, measured in energy, this is
likely to be negligible compared to the reduced communication
overhead.
For the setting with constrained server and server-only
authentication, the server only needs to be provisioned with the C509
certificate and does not perform the conversion to X.509. This
option is viable when client authentication can be asserted by other
means.
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For protocols like IKEv2, TLS/DTLS 1.3, and EDHOC, where certificates
are encrypted, the proposed encoding needs to be done fully end-to-
end, through adding the encoding/decoding functionality to the
server.
6.2. Expected Certificate Sizes
The CBOR encoding of the sample certificate chains given in
Appendix A results in the numbers shown in Figures 4 and 5.
COSE_X509 is defined in [RFC9360] and COSE_C509 is defined in
Section 8.16. After [RFC7925] profiling, most duplicated information
has been removed, and the remaining text strings are minimal in size.
Therefore, the further size reduction reached with general
compression mechanisms such as Brotli [RFC7932] will be small, mainly
corresponding to making the ASN.1 encoding more compact. CBOR
encoding can however significantly compress RFC 7925 profiled
certificates. In the examples with HTTPS certificate chains
(www.ietf.org (ECDSA) and cabforum.org (RSA)) both C509 and Brotli
perform well complementing each other. C509 uses dedicated
information to compress individual certificates, while Brotli can
compress duplicate information in the entire chain. Note that C509
certificates of type 2 and 3 have the same size. For Brotli, the
Rust crate Brotli 3.3.0 was used with compression level 11 and window
size 22.
In the examples using FN-DSA and ML-DSA certificate chains, the
largest portion of the certificate size consists of the public keys
and signatures, which are essentially random. As a result, both
Brotli and C509 achieve only very limited size reduction. However,
C509 still performs slightly better.
+----------------------------------------+-----------+-----------+
| Description (number of certs) | COSE_X509 | COSE_C509 |
+----------------------------------------+-----------+-----------+
| RFC 7925 profiled IoT Certificate (1) | 319 | 142 |
+----------------------------------------+-----------+-----------+
| RPKI Certificate (1) | 20981 | 11523 |
+----------------------------------------+-----------+-----------+
| ECDSA HTTPS Certificate Chain (2) | 1644 | 1012 |
+----------------------------------------+-----------+-----------+
| RSA HTTPS Certificate Chain (2) | 2909 | 2240 |
+----------------------------------------+-----------+-----------+
| FN-DSA-512 HTTPS Certificate Chain (2) | 4417 | 3897 |
+----------------------------------------+-----------+-----------+
| ML-DSA-65 HTTPS Certificate Chain (2) | 11863 | 11318 |
+----------------------------------------+-----------+-----------+
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Figure 4: Comparing Sizes of Certificate Chains in COSE. Number
of bytes (length of certificate chain).
+-----------------------+-------+---------+-------+--------+
| Description | X.509 | X.509 + | C509 | C509 + |
| (number of certs) | | Brotli | | Brotli |
+-----------------------+-------+---------+-------+--------+
| RFC 7925 profiled | 325 | 317 | 149 | 158 |
| IoT Certificate (1) | | | | |
+-----------------------+-------+---------+-------+--------+
| RPKI Certificate (1) | 20987 | 9109 | 11529 | 7020 |
+-----------------------+-------+---------+-------+--------+
| ECDSA HTTPS | 1651 | 1181 | 1019 | 930 |
| Certificate Chain (2) | | | | |
+-----------------------+-------+---------+-------+--------+
| RSA HTTPS | 2656 | 2195 | 2071 | 1913 |
| Certificate Chain (2) | | | | |
+-----------------------+-------+---------+-------+--------+
| FN-DSA-512 HTTPS | 4437 | 4026 | 3917 | 3776 |
| Certificate Chain (2) | | | | |
+-----------------------+-------+---------+-------+--------+
| ML-DSA-65 HTTPS | 11869 | 11420 | 11325 | 11148 |
| Certificate Chain (2) | | | | |
+-----------------------+-------+---------+-------+--------+
Figure 5: Comparing Sizes of Certificate Chains with TLS 1.3.
Number of bytes (length of certificate chain). X.509 and C509
are Certificate messages. X.509 + Brotli and C509 + Brotli are
CompressedCertificate messages.
7. Security Considerations
The CBOR encoding of X.509 certificates does not change the security
assumptions needed when deploying standard X.509 certificates but
decreases the number of fields transmitted, which reduces the risk
for implementation errors. The security considerations of [RFC5280]
apply.
The use of natively signed C509 certificates removes the need for
ASN.1 encoding, which is a rich source of security vulnerabilities.
Conversion between the certificate formats can be made in constant
time to reduce risk of information leakage through side channels.
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The mechanism in this document does not reveal any additional
information compared to X.509. Because of the difference in size, it
will be possible to detect that this profile is used. The gateway
solution described in Section 6.1 requires unencrypted certificates
and is not recommended.
Any issues with decoding or parsing a C509 certificate should be
handled exactly as how such errors would be handled for the
corresponding X.509 certificate. For example, a non-critical
extension MAY be ignored if it is not recognized, see Section 4.2 of
[RFC5280].
As stated in Section 3.4, the contents of the COSE Header Parameters
c5b, c5c, c5t, c5u is untrusted input that potentially may be
verified using existing trust anchors or other trust establishment
mechanism out of scope of this document. Similar security
considerations as x5bag, x5chain, x5t and x5u applies, see [RFC9360].
Security considerations of the COSE protected and unprotected headers
is discussed in [RFC9052].
8. IANA Considerations
This document creates several new registries in the new registry
group "CBOR Encoded X.509 (C509) Parameters". For all items, the
'Reference' field points to this document.
Editor's note: Add informative reference to the newly created IANA
registries and updated existing registries.
8.1. Designated Expert Guidance
The expert reviewers for the registries defined in this document are
expected to ensure that the usage solves a valid use case that could
not be solved better in a different way, that it is not going to
duplicate an entry that is already registered, and that the
registered point is likely to be used in deployments. They are
furthermore expected to check the clarity of purpose and use of the
requested code points. Experts should take into account the expected
usage of entries when approving point assignment, and the length of
the encoded value should be weighed against the number of code points
left that encode to that size and how constrained the systems it will
be used on are. Values in the interval [-24, 23] have a 1-byte
encoding, other values in the interval [-256, 255] have a 2-byte
encoding, and the remaining values in the interval [-65536, 65535]
have a 3-byte encoding.
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All assignments according to "IETF Review with Expert Review" are
made on a "IETF Review" basis per Section 4.8 of [RFC8126] with
"Expert Review" additionally required per Section 4.5 of [RFC8126].
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, working group chairs
are encouraged to consult the expert(s) early during the process
outlined in Section 3.1 of [RFC7120].
8.2. C509 Certificate Types Registry
IANA has created a new registry titled "C509 Certificate Types" under
the registry group "CBOR Encoded X.509 (C509) Parameters". The
fields of the registry are Value, Description, and Reference, where
Value is an integer, and the other columns are text strings. It is
mandatory to specify content in all columns. For values in the
interval [-24, 23], the registration procedure is "IETF Review with
Expert Review". For all other values, the registration procedure is
"Expert Review". The initial contents of the registry are (see
Section 3.1.1):
+-------+-------------------------------------------+
| Value | Description |
+=======+===========================================+
| 0 | Reserved |
+-------+-------------------------------------------+
| 1 | Reserved |
+-------+-------------------------------------------+
| 2 | Natively Signed C509 Certificate |
+-------+-------------------------------------------+
| 3 | CBOR Re-encoded X.509 v3 Certificate |
+-------+-------------------------------------------+
Figure 6: C509 Certificate Types
8.3. C509 Certification Request Types Registry
IANA has created a new registry titled "C509 Certification Request
Types" under the new registry group "CBOR Encoded X.509 (C509)
Parameters". The fields of the registry are Value, Description, and
Reference, where Value is an integer, and the other columns are text
strings. All columns are mandatory. For values in the interval
[-24, 23] the registration procedure is "IETF Review with Expert
Review". For all other values the registration procedure is "Expert
Review". The initial contents of the registry are:
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+-------+-----------------------------------------------------------+
| Value | Description |
+=======+===========================================================+
| 0 | Reserved |
+-------+-----------------------------------------------------------+
| 1 | Reserved |
+-------+-----------------------------------------------------------+
| 2 | Natively Signed C509 Certification Request. |
+-------+-----------------------------------------------------------+
| 3 | CBOR re-encoding of RFC 2986 certification request. |
+-------+-----------------------------------------------------------+
Figure 7: C509 Certification Request Types
8.4. C509 Private Key Types Registry
IANA has created a new registry titled "C509 Private Key Types" in
the new registry group "CBOR Encoded X.509 (C509) Parameters". The
fields of the registry are Value, Comments, and subjectPrivateKey,
and Reference, where Value is an integer, and the other columns are
text strings. All columns are mandatory. For values in the interval
[-24, 23] the registration procedure is "IETF Review with Expert
Review". For all other values the registration procedure is "Expert
Review". The initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | Private Key Types |
+=======+===========================================================+
| 0 | Comments: Asymmetric Key Package (RFC 5958) |
| | subjectPrivateKey: bytes |
+-------+-----------------------------------------------------------+
| 1 | Comments: COSE Key Object (RFC 9052) |
| | subjectPrivateKey: COSE_Key |
+-------+-----------------------------------------------------------+
Figure 8: C509 Private Key Types
8.5. C509 Certification Request Templates Types Registry
IANA has created a new registry titled "C509 Certification Request
Templates Types" under the new registry group "CBOR Encoded X.509
(C509) Parameters". The columns of the registry are Value,
Description, and Reference, where Value is an integer, and the other
columns are text strings. All columns are mandatory. For values in
the interval [-24, 23] the registration procedure is "IETF Review"
and "Expert Review". For all other values the registration procedure
is "Expert Review". The initial contents of the registry are:
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+-------+-----------------------------------------------------------+
| Value | Description |
+=======+===========================================================+
| 0 | Simple C509 Certification Request Template |
+-------+-----------------------------------------------------------+
Figure 9: C509 Certification Request Templates Types
8.6. C509 RDN Attributes Registry
IANA has created a new registry titled "C509 RDN Attributes" in the
new registry group "CBOR Encoded X.509 (C509) Parameters". The
fields of the registry are Value, Name, Identifiers, OID, DER,
Comments and Reference, where Value is a non-negative integer, and
the other columns are text strings. Name and Identifiers are
informal descriptions. The fields Name, OID, and DER are mandatory.
For values in the interval [0, 23] the registration procedure is
"IETF Review with Expert Review". Values ≥ 32768 are reserved for
Private Use. For all other values the registration procedure is
"Expert Review". Name and Identifiers are informal descriptions. If
OID is present, the OID is given in dotted decimal representation,
and the DER column contains the hex string of the DER-encoded OID
[X.690].
The initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | RDN Attribute |
+=======+===========================================================+
| 0 | Name: Email Address |
| | Identifiers: emailAddress, e-mailAddress |
| | OID: 1.2.840.113549.1.9.1 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 01 |
| | Comments: RFC 2985 |
+-------+-----------------------------------------------------------+
| 1 | Name: Common Name |
| | Identifiers: commonName, cn |
| | OID: 2.5.4.3 |
| | DER: 06 03 55 04 03 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 2 | Name: Surname |
| | Identifiers: surname, sn |
| | OID: 2.5.4.4 |
| | DER: 06 03 55 04 04 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 3 | Name: Serial Number |
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| | Identifiers: serialNumber |
| | OID: 2.5.4.5 |
| | DER: 06 03 55 04 05 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 4 | Name: Country |
| | Identifiers: countryName, c |
| | OID: 2.5.4.6 |
| | DER: 06 03 55 04 06 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 5 | Name: Locality |
| | Identifiers: localityName, locality, l |
| | OID: 2.5.4.7 |
| | DER: 06 03 55 04 07 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 6 | Name: State or Province |
| | Identifiers: stateOrProvinceName, st |
| | OID: 2.5.4.8 |
| | DER: 06 03 55 04 08 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 7 | Name: Street Address |
| | Identifiers: streetAddress, street |
| | OID: 2.5.4.9 |
| | DER: 06 03 55 04 09 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 8 | Name: Organization |
| | Identifiers: organizationName, o |
| | OID: 2.5.4.10 |
| | DER: 06 03 55 04 0A |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 9 | Name: Organizational Unit |
| | Identifiers: organizationalUnitName, ou |
| | OID: 2.5.4.11 |
| | DER: 06 03 55 04 0B |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 10 | Name: Title |
| | Identifiers: title |
| | OID: 2.5.4.12 |
| | DER: 06 03 55 04 0C |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 11 | Name: Business Category |
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| | Identifiers: businessCategory |
| | OID: 2.5.4.15 |
| | DER: 06 03 55 04 0F |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 12 | Name: Postal Code |
| | Identifiers: postalCode |
| | OID: 2.5.4.17 |
| | DER: 06 03 55 04 11 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 13 | Name: Given Name |
| | Identifiers: givenName |
| | OID: 2.5.4.42 |
| | DER: 06 03 55 04 2A |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 14 | Name: Initials |
| | Identifiers: initials |
| | OID: 2.5.4.43 |
| | DER: 06 03 55 04 2B |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 15 | Name: Generation Qualifier |
| | Identifiers: generationQualifier |
| | OID: 2.5.4.44 |
| | DER: 06 03 55 04 2C |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 16 | Name: DN Qualifier |
| | Identifiers: dnQualifier |
| | OID: 2.5.4.46 |
| | DER: 06 03 55 04 2E |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 17 | Name: Pseudonym |
| | Identifiers: pseudonym |
| | OID: 2.5.4.65 |
| | DER: 06 03 55 04 41 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 18 | Name: Organization Identifier |
| | Identifiers: organizationIdentifier |
| | OID: 2.5.4.97 |
| | DER: 06 03 55 04 61 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 19 | Name: Jurisdiction Locality Name |
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| | Identifiers: jurisdictionLocalityName |
| | OID: 1.3.6.1.4.1.311.60.2.1.1 |
| | DER: 06 0B 2B 06 01 04 01 82 37 3C 02 01 01 |
| | Comments: Proprietary Microsoft Attribute |
+-------+-----------------------------------------------------------+
| 20 | Name: Jurisdiction State or Province |
| | Identifiers: jurisdictionStateOrProvinceName |
| | OID: 1.3.6.1.4.1.311.60.2.1.2 |
| | DER: 06 0B 2B 06 01 04 01 82 37 3C 02 01 02 |
| | Comments: Proprietary Microsoft Attribute |
+-------+-----------------------------------------------------------+
| 21 | Name: Jurisdiction Country Name |
| | Identifiers: jurisdictionCountryName |
| | OID: 1.3.6.1.4.1.311.60.2.1.3 |
| | DER: 06 0B 2B 06 01 04 01 82 37 3C 02 01 03 |
| | Comments: Proprietary Microsoft Attribute |
+-------+-----------------------------------------------------------+
| 22 | Name: Domain Component |
| | Identifiers: domainComponent, dc |
| | OID: 0.9.2342.19200300.100.1.25 |
| | DER: 06 0A 09 92 26 89 93 F2 2C 64 01 19 |
| | Comments: RFC 1274 |
+-------+-----------------------------------------------------------+
| 25 | Name: Name |
| | Identifiers: name |
| | OID: 2.5.4.41 |
| | DER: 06 03 55 04 29 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 26 | Name: Telephone Number |
| | Identifiers: telephoneNumber |
| | OID: 2.5.4.20 |
| | DER: 06 03 55 04 14 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 27 | Name: Directory Management Domain Name |
| | Identifiers: dmdName |
| | OID: 2.5.4.54 |
| | DER: 06 03 55 04 36 |
| | Comments: X.520 |
+-------+-----------------------------------------------------------+
| 28 | Name: userid |
| | Identifiers: uid |
| | OID: 0.9.2342.19200300.100.1.1 |
| | DER: 06 0A 09 92 26 89 93 F2 2C 64 01 01 |
| | Comments: RFC 1274 |
+-------+-----------------------------------------------------------+
| 29 | Name: Unstructured Name |
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| | Identifiers: unstructuredName |
| | OID: 1.2.840.113549.1.9.2 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 02 |
| | Comments: RFC 2985 |
+-------+-----------------------------------------------------------+
| 30 | Name: Unstructured Address |
| | Identifiers: unstructuredAddress |
| | OID: 1.2.840.113549.1.9.8 |
| | DER: 06 0A 2A 86 48 86 F7 0D 01 09 08 00 |
| | Comments: RFC 2985 |
+-------+-----------------------------------------------------------+
Figure 10: C509 RDN Attributes
8.7. C509 CR Attributes Registry
IANA has created a new registry titled "C509 CR Attributes" under the
registry group "CBOR Encoded X.509 (C509) Parameters". The fields of
the registry are Value, Name, Identifiers, OID, DER, Comments,
attributeValue, and Reference, where Value is an integer, and the
other columns are text strings. Name and Identifiers are informal
descriptions. The fields Name, OID, and DER are mandatory. For
values in the interval [-24, 23] the registration procedure is "IETF
Review with Expert Review". Values ≥ 32768 are reserved for Private
Use. For all other values the registration procedure is "Expert
Review". Name and Identifiers are informal descriptions. If OID is
present, the OID is given in dotted decimal representation, and the
DER column contains the hex string of the DER-encoded OID [X.690].
The initial contents of the registry are:
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+-------+-----------------------------------------------------------+
| Value | CR Attribute |
+=======+===========================================================+
| 0 | Name: Extension Request |
| | Identifiers: extensionRequest |
| | OID: 1.2.840.113549.1.9.14 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 0E |
| | Comments: RFC 2985 |
| | attributeValue: Extensions |
+-------+-----------------------------------------------------------+
| 1 | Name: Challenge Password |
| | Identifiers: challengePassword |
| | OID: 1.2.840.113549.1.9.7 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 07 |
| | Comments: RFC 2985 |
| | attributeValue: ChallengePassword |
+-------+-----------------------------------------------------------+
| 2 | Name: Private Key Possession Statement |
| | Identifiers: privateKeyPossessionStatement |
| | OID: 1.3.6.1.4.1.22112.2.1 |
| | DER: 06 0A 2B 06 01 04 01 81 AC 60 02 01 |
| | Comments: RFC 9883 |
| | attributeValue: PrivateKeyPossessionStatement |
+-------+-----------------------------------------------------------+
Figure 11: C509 CRAttributes
8.8. C509 Extensions Registry
IANA has created a new registry titled "C509 Extensions Registry"
under the new registry group "CBOR Encoded X.509 (C509) Parameters".
The fields of the registry are Value, Name, Identifiers, OID, DER,
Comments, extensionValue, and Reference, where Value is a positive
integer, and the other columns are text strings. The fields Name,
OID, DER, and extensionValue are mandatory. For values in the
interval [1, 23] the registration procedure is "IETF Review with
Expert Review". Values ≥ 32768 are reserved for Private Use. For all
other values the registration procedure is "Expert Review". The
initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | Extension |
+=======+===========================================================+
| 1 | Name: Subject Key Identifier |
| | Identifiers: subjectKeyIdentifier |
| | OID: 2.5.29.14 |
| | DER: 06 03 55 1D 0E |
| | Comments: RFC 5280 |
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| | extensionValue: SubjectKeyIdentifier |
+-------+-----------------------------------------------------------+
| 2 | Name: Key Usage |
| | Identifiers: keyUsage |
| | OID: 2.5.29.15 |
| | DER: 06 03 55 1D 0F |
| | Comments: RFC 5280 |
| | AttributeValue: KeyUsage |
+-------+-----------------------------------------------------------+
| 3 | Name: Subject Alternative Name |
| | Identifiers: subjectAltName |
| | OID: 2.5.29.17 |
| | DER: 06 03 55 1D 11 |
| | Comments: RFC 5280 |
| | extensionValue: SubjectAltName |
+-------+-----------------------------------------------------------+
| 4 | Name: Basic Constraints |
| | Identifiers: basicConstraints |
| | OID: 2.5.29.19 |
| | DER: 06 03 55 1D 13 |
| | Comments: RFC 5280 |
| | extensionValue: BasicConstraints |
+-------+-----------------------------------------------------------+
| 5 | Name: CRL Distribution Points |
| | Identifiers: cRLDistributionPoints |
| | OID: 2.5.29.31 |
| | DER: 06 03 55 1D 1F |
| | Comments: RFC 5280 |
| | extensionValue: CRLDistributionPoints |
+-------+-----------------------------------------------------------+
| 6 | Name: Certificate Policies |
| | Identifiers: certificatePolicies |
| | OID: 2.5.29.32 |
| | DER: 06 03 55 1D 20 |
| | Comments: RFC 5280 |
| | extensionValue: CertificatePolicies |
+-------+-----------------------------------------------------------+
| 7 | Name: Authority Key Identifier |
| | Identifiers: authorityKeyIdentifier |
| | OID: 2.5.29.35 |
| | DER: 06 03 55 1D 23 |
| | Comments: RFC 5280 |
| | extensionValue: AuthorityKeyIdentifier |
+-------+-----------------------------------------------------------+
| 8 | Name: Extended Key Usage |
| | Identifiers: extKeyUsage |
| | OID: 2.5.29.37 |
| | DER: 06 03 55 1D 25 |
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| | Comments: RFC 5280 |
| | extensionValue: ExtKeyUsageSyntax |
+-------+-----------------------------------------------------------+
| 9 | Name: Authority Information Access |
| | Identifiers: authorityInfoAccess |
| | OID: 1.3.6.1.5.5.7.1.1 |
| | DER: 06 08 2B 06 01 05 05 07 01 01 |
| | Comments: RFC 5280 |
| | extensionValue: AuthorityInfoAccessSyntax |
+-------+-----------------------------------------------------------+
| 24 | Name: Subject Directory Attributes |
| | Identifiers: subjectDirectoryAttributes |
| | OID: 2.5.29.9 |
| | DER: 06 03 55 1D 09 |
| | Comments: RFC 5280 |
| | extensionValue: SubjectDirectoryAttributes |
+-------+-----------------------------------------------------------+
| 25 | Name: Issuer Alternative Name |
| | Identifiers: issuerAltName |
| | OID: 2.5.29.18 |
| | DER: 06 03 55 1D 12 |
| | Comments: RFC 5280 |
| | extensionValue: IssuerAltName |
+-------+-----------------------------------------------------------+
| 26 | Name: Name Constraints |
| | Identifiers: nameConstraints |
| | OID: 2.5.29.30 |
| | DER: 06 03 55 1D 1E |
| | Comments: RFC 9549 |
| | extensionValue: NameConstraints |
+-------+-----------------------------------------------------------+
| 27 | Name: Policy Mappings |
| | Identifiers: policyMappings |
| | OID: 2.5.29.33 |
| | DER: 06 03 55 1D 21 |
| | Comments: RFC 5280 |
| | extensionValue: PolicyMappings |
+-------+-----------------------------------------------------------+
| 28 | Name: Policy Constraints |
| | Identifiers: policyConstraints |
| | OID: 2.5.29.36 |
| | DER: 06 03 55 1D 24 |
| | Comments: RFC 5280 |
| | extensionValue: PolicyConstraints |
+-------+-----------------------------------------------------------+
| 29 | Name: Freshest CRL |
| | Identifiers: freshestCRL |
| | OID: 2.5.29.46 |
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| | DER: 06 03 55 1D 2E |
| | Comments: RFC 5280 |
| | extensionValue: FreshestCRL |
+-------+-----------------------------------------------------------+
| 30 | Name: Inhibit anyPolicy |
| | Identifiers: inhibitAnyPolicy |
| | OID: 2.5.29.54 |
| | DER: 06 03 55 1D 36 |
| | Comments: RFC 5280 |
| | extensionValue: InhibitAnyPolicy |
+-------+-----------------------------------------------------------+
| 31 | Name: Subject Information Access |
| | Identifiers: subjectInfoAccess |
| | OID: 1.3.6.1.5.5.7.1.11 |
| | DER: 06 08 2B 06 01 05 05 07 01 0B |
| | Comments: RFC 5280 |
| | extensionValue: SubjectInfoAccessSyntax |
+-------+-----------------------------------------------------------+
| 32 | Name: IPAddrBlocks |
| | Identifiers: id-pe-ipAddrBlocks |
| | OID: 1.3.6.1.5.5.7.1.7 |
| | DER: 06 08 2B 06 01 05 05 07 01 07 |
| | Comments: RFC 3779 |
| | extensionValue: IPAddrBlocks |
+-------+-----------------------------------------------------------+
| 33 | Name: AS Identifiers |
| | Identifiers: id-pe-autonomousSysIds |
| | OID: 1.3.6.1.5.5.7.1.8 |
| | DER: 06 08 2B 06 01 05 05 07 01 08 |
| | Comments: RFC 3779 |
| | extensionValue: ASIdentifiers |
+-------+-----------------------------------------------------------+
| 34 | Name: IPAddrBlocks v2 |
| | Identifiers: id-pe-ipAddrBlocks-v2 |
| | OID: 1.3.6.1.5.5.7.1.28 |
| | DER: 06 08 2B 06 01 05 05 07 01 1C |
| | Comments: RFC 8360 |
| | extensionValue: IPAddrBlocks |
+-------+-----------------------------------------------------------+
| 35 | Name: AS Identifiers v2 |
| | Identifiers: id-pe-autonomousSysIds-v2 |
| | OID: 1.3.6.1.5.5.7.1.29 |
| | DER: 06 08 2B 06 01 05 05 07 01 1D |
| | Comments: RFC 8360 |
| | extensionValue: ASIdentifiers |
+-------+-----------------------------------------------------------+
| 36 | Name: OCSP No Check |
| | Identifiers: id-pkix-ocsp-nocheck |
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| | OID: 1.3.6.1.5.5.7.48.1.5 |
| | DER: 06 09 2B 06 01 05 05 07 30 01 05 |
| | Comments: RFC 6960 |
| | extensionValue: null |
+-------+-----------------------------------------------------------+
| 37 | Name: Precertificate Signing Certificate |
| | Identifiers: |
| | OID: 1.3.6.1.4.1.11129.2.4.3 |
| | DER: 06 0A 2B 06 01 04 01 D6 79 02 04 03 |
| | Comments: RFC 6962 |
| | extensionValue: null |
+-------+-----------------------------------------------------------+
| 38 | Name: TLS Features |
| | Identifiers: id-pe-tlsfeature |
| | OID: 1.3.6.1.5.5.7.1.24 |
| | DER: 06 08 2B 06 01 05 05 07 01 18 |
| | Comments: RFC 7633 |
| | extensionValue: TLSFeatures |
+-------+-----------------------------------------------------------+
Figure 12: C509 Extensions
8.9. C509 Certificate Policies Registry
IANA has created a new registry titled "C509 Certificate Policies
Registry" under the registry group "CBOR Encoded X.509 (C509)
Parameters". The fields of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. The fields Name,
OID, and DER are mandatory. For values in the interval [-24, 23] the
registration procedure is "IETF Review with Expert Review". Values ≥
32768 are reserved for Private Use. For all other values the
registration procedure is "Expert Review". The initial contents of
the registry are:
+-------+-----------------------------------------------------------+
| Value | Certificate Policy |
+=======+===========================================================+
| 0 | Name: Any Policy |
| | Identifiers: anyPolicy |
| | OID: 2.5.29.32.0 |
| | DER: 06 04 55 1D 20 00 |
| | Comments: RFC 5280 |
+-------+-----------------------------------------------------------+
| 1 | Name: Domain Validation (DV) |
| | Identifiers: domain-validated |
| | OID: 2.23.140.1.2.1 |
| | DER: 06 06 67 81 0C 01 02 01 |
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| | Comments: CA/Browser Forum |
+-------+-----------------------------------------------------------+
| 2 | Name: Organization Validation (OV) |
| | Identifiers: organization-validated |
| | OID: 2.23.140.1.2.2 |
| | DER: 06 06 67 81 0C 01 02 02 |
| | Comments: CA/Browser Forum |
+-------+-----------------------------------------------------------+
| 3 | Name: Individual Validation (IV) |
| | Identifiers: individual-validated |
| | OID: 2.23.140.1.2.3 |
| | DER: 06 06 67 81 0C 01 02 03 |
| | Comments: CA/Browser Forum |
+-------+-----------------------------------------------------------+
| 4 | Name: Extended Validation (EV) |
| | Identifiers: ev-guidelines |
| | OID: 2.23.140.1.1 |
| | DER: 06 05 67 81 0C 01 01 |
| | Comments: CA/Browser Forum |
+-------+-----------------------------------------------------------+
| 7 | Name: Resource PKI (RPKI) |
| | Identifiers: id-cp-ipAddr-asNumber |
| | OID: 1.3.6.1.5.5.7.14.2 |
| | DER: 06 08 2B 06 01 05 05 07 0E 02 |
| | Comments: RFC 3779 |
+-------+-----------------------------------------------------------+
| 8 | Name: Resource PKI (RPKI) (Alternative) |
| | Identifiers: id-cp-ipAddr-asNumber-v2 |
| | OID: 1.3.6.1.5.5.7.14.3 |
| | DER: 06 08 2B 06 01 05 05 07 0E 03 |
| | Comments: RFC 8360 |
+-------+-----------------------------------------------------------+
| 24 | Name: Remote SIM Provisioning Role |
| | Certificate Issuer |
| | Identifiers: id-rspRole-ci |
| | OID: 2.23.146.1.2.1.0 |
| | DER: 06 07 67 81 12 01 02 01 00 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 25 | Name: Remote SIM Provisioning Role |
| | eUICC v2 |
| | Identifiers: id-rspRole-euicc-v2 |
| | OID: 2.23.146.1.2.1.1 |
| | DER: 06 07 67 81 12 01 02 01 01 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 26 | Name: Remote SIM Provisioning Role |
| | eUICC |
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| | Identifiers: id-rspRole-euicc |
| | OID: 2.23.146.1.2.1.0.0.0.0.0 |
| | DER: 06 0B 67 81 12 01 02 01 00 00 00 00 00 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 27 | Name: Remote SIM Provisioning Role |
| | eUICC Manufacturer v2 |
| | Identifiers: id-rspRole-eum-v2 |
| | OID: 2.23.146.1.2.1.2 |
| | DER: 06 07 67 81 12 01 02 01 02 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 28 | Name: Remote SIM Provisioning Role |
| | eUICC Manufacturer |
| | Identifiers: id-rspRole-eum |
| | OID: 2.23.146.1.2.1.0.0.0 |
| | DER: 06 09 67 81 12 01 02 01 00 00 00 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 29 | Name: Remote SIM Provisioning Role |
| | SM-DP+ TLS v2 |
| | Identifiers: id-rspRole-dp-tls-v2 |
| | OID: 2.23.146.1.2.1.3 |
| | DER: 06 07 67 81 12 01 02 01 03 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 30 | Name: Remote SIM Provisioning Role |
| | SM-DP+ TLS |
| | Identifiers: id-rspRole-dp-tls |
| | OID: 2.23.146.1.2.1.0.0.1.0 |
| | DER: 06 0A 67 81 12 01 02 01 00 00 01 00 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 31 | Name: Remote SIM Provisioning Role |
| | SM-DP+ Authentication v2 |
| | Identifiers: id-rspRole-dp-auth-v2 |
| | OID: 2.23.146.1.2.1.4 |
| | DER: 06 07 67 81 12 01 02 01 04 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 32 | Name: Remote SIM Provisioning Role |
| | SM-DP+ Authentication |
| | Identifiers: id-rspRole-dp-auth |
| | OID: 2.23.146.1.2.1.0.0.1.1 |
| | DER: 06 0A 67 81 12 01 02 01 00 00 01 01 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 33 | Name: Remote SIM Provisioning Role |
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| | SM-DP+ Profile Binding v2 |
| | Identifiers: id-rspRole-dp-pb-v2 |
| | OID: 2.23.146.1.2.1.5 |
| | DER: 06 07 67 81 12 01 02 01 05 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 34 | Name: Remote SIM Provisioning Role |
| | SM-DP+ Profile Binding |
| | Identifiers: id-rspRole-dp-pb |
| | OID: 2.23.146.1.2.1.0.0.1.2 |
| | DER: 06 0A 67 81 12 01 02 01 00 00 01 02 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 35 | Name: Remote SIM Provisioning Role |
| | SM-DS TLS v2 |
| | Identifiers: id-rspRole-ds-tls-v2 |
| | OID: 2.23.146.1.2.1.6 |
| | DER: 06 07 67 81 12 01 02 01 06 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 36 | Name: Remote SIM Provisioning Role |
| | SM-DS TLS |
| | Identifiers: id-rspRole-ds-tls |
| | OID: 2.23.146.1.2.1.0.0.2.0 |
| | DER: 06 0A 67 81 12 01 02 01 00 00 02 00 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 37 | Name: Remote SIM Provisioning Role |
| | SM-DS Authentication v2 |
| | Identifiers: id-rspRole-ds-auth-v2 |
| | OID: 2.23.146.1.2.1.7 |
| | DER: 06 07 67 81 12 01 02 01 07 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
| 38 | Name: Remote SIM Provisioning Role |
| | SM-DS Authentication |
| | Identifiers: id-rspRole-ds-auth |
| | OID: 2.23.146.1.2.1.0.0.2.1 |
| | DER: 06 0A 67 81 12 01 02 01 00 00 02 01 |
| | Comments: GSMA SGP.22 |
+-------+-----------------------------------------------------------+
Figure 13: C509 Certificate Policies
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8.10. C509 Policies Qualifiers Registry
IANA has created a new registry titled "C509 Policies Qualifiers
Registry" under the registry group "CBOR Encoded X.509 (C509)
Parameters". The fields of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. The fields Name,
OID, and DER are mandatory. For values in the interval [-24, 23] the
registration procedure is "IETF Review with Expert Review". Values ≥
32768 are reserved for Private Use. For all other values the
registration procedure is "Expert Review". The initial contents of
the registry are:
+-------+-----------------------------------------------------------+
| Value | Certificate Policy |
+=======+===========================================================+
| 1 | Name: Certification Practice Statement |
| | Identifiers: id-qt-cps, cps |
| | OID: 1.3.6.1.5.5.7.2.1 |
| | DER: 06 08 2B 06 01 05 05 07 02 01 |
| | Comments: RFC 5280 |
+-------+-----------------------------------------------------------+
| 2 | Name: User Notice |
| | Identifiers: id-qt-unotice, unotice |
| | OID: 1.3.6.1.5.5.7.2.2 |
| | DER: 06 08 2B 06 01 05 05 07 02 02 |
| | Comments: RFC 5280 |
+-------+-----------------------------------------------------------+
Figure 14: C509 Policies Qualifiers
8.11. C509 Information Access Registry
IANA has created a new registry titled "C509 Information Access
Registry" under the registry group "CBOR Encoded X.509 (C509)
Parameters". The fields of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. The fields Name,
OID, and DER are mandatory. For values in the interval [-24, 23] the
registration procedure is "IETF Review with Expert Review". For all
other values the registration procedure is "Expert Review". The
initial contents of the registry are:
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+-------+-----------------------------------------------------------+
| Value | Information Access |
+=======+===========================================================+
| 1 | Name: OCSP |
| | Identifiers: id-ad-ocsp, id-pkix-ocsp |
| | OID: 1.3.6.1.5.5.7.48.1 |
| | DER: 06 08 2B 06 01 05 05 07 30 01 |
| | Comments: RFC 5280 |
+-------+-----------------------------------------------------------+
| 2 | Name: CA Issuers |
| | Identifiers: id-ad-caIssuers, caIssuers |
| | OID: 1.3.6.1.5.5.7.48.2 |
| | DER: 06 08 2B 06 01 05 05 07 30 02 |
| | Comments: RFC 5280 |
+-------+-----------------------------------------------------------+
| 3 | Name: Time Stamping |
| | Identifiers: id-ad-timeStamping, timeStamping |
| | OID: 1.3.6.1.5.5.7.48.3 |
| | DER: 06 08 2B 06 01 05 05 07 30 03 |
| | Comments: RFC 3161 |
+-------+-----------------------------------------------------------+
| 5 | Name: CA Repository |
| | Identifiers: id-ad-caRepository |
| | OID: 1.3.6.1.5.5.7.48.5 |
| | DER: 06 08 2B 06 01 05 05 07 30 05 |
| | Comments: RFC 5280 |
+-------+-----------------------------------------------------------+
| 10 | Name: RPKI Manifest |
| | Identifiers: id-ad-rpkiManifest |
| | OID: 1.3.6.1.5.5.7.48.10 |
| | DER: 06 08 2B 06 01 05 05 07 30 0A |
| | Comments: RFC 6487 |
+-------+-----------------------------------------------------------+
| 11 | Name: Signed Object |
| | Identifiers: id-ad-signedObject |
| | OID: 1.3.6.1.5.5.7.48.11 |
| | DER: 06 08 2B 06 01 05 05 07 30 0B |
| | Comments: RFC 6487 |
+-------+-----------------------------------------------------------+
| 13 | Name: RPKI Notify |
| | Identifiers: id-ad-rpkiNotify |
| | OID: 1.3.6.1.5.5.7.48.13 |
| | DER: 06 08 2B 06 01 05 05 07 30 0D |
| | Comments: RFC 8182 |
+-------+-----------------------------------------------------------+
Figure 15: C509 Information Accesses
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8.12. C509 Extended Key Usages Registry
IANA has created a new registry titled "C509 Extended Key Usages
Registry" under the registry group "CBOR Encoded X.509 (C509)
Parameters". The fields of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. The fields Name,
OID, and DER are mandatory. For values in the interval [-24, 23] the
registration procedure is "IETF Review with Expert Review". Values ≥
32768 are reserved for Private Use. For all other values the
registration procedure is "Expert Review". The initial contents of
the registry are:
+-------+---------------------------------------------------------+
| Value | Extended Key Usage |
+=======+=========================================================+
| 0 | Name: Any Extended Key Usage |
| | Identifiers: anyExtendedKeyUsage |
| | OID: 2.5.29.37.0 |
| | DER: 06 04 55 1D 25 00 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 1 | Name: TLS Server authentication |
| | Identifiers: id-kp-serverAuth |
| | OID: 1.3.6.1.5.5.7.3.1 |
| | DER: 06 08 2B 06 01 05 05 07 03 01 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 2 | Name: TLS Client Authentication |
| | Identifiers: id-kp-clientAuth |
| | OID: 1.3.6.1.5.5.7.3.2 |
| | DER: 06 08 2B 06 01 05 05 07 03 02 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 3 | Name: Code Signing |
| | Identifiers: id-kp-codeSigning |
| | OID: 1.3.6.1.5.5.7.3.3 |
| | DER: 06 08 2B 06 01 05 05 07 03 03 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 4 | Name: Email protection (S/MIME) |
| | Identifiers: id-kp-emailProtection |
| | OID: 1.3.6.1.5.5.7.3.4 |
| | DER: 06 08 2B 06 01 05 05 07 03 04 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 8 | Name: Time Stamping |
| | Identifiers: id-kp-timeStamping, timestamping |
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| | OID: 1.3.6.1.5.5.7.3.8 |
| | DER: 06 08 2B 06 01 05 05 07 03 08 |
| | Comments: RFC 3161 |
+-------+---------------------------------------------------------+
| 9 | Name: OCSP Signing |
| | Identifiers: id-kp-OCSPSigning |
| | OID: 1.3.6.1.5.5.7.3.9 |
| | DER: 06 08 2B 06 01 05 05 07 03 09 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 10 | Name: Kerberos PKINIT Client Auth |
| | Identifiers: id-pkinit-KPClientAuth |
| | OID: 1.3.6.1.5.2.3.4 |
| | DER: 06 07 2B 06 01 05 02 03 04 |
| | Comments: RFC 4556 |
+-------+---------------------------------------------------------+
| 11 | Name: Kerberos PKINIT KDC |
| | Identifiers: id-pkinit-KPKdc |
| | OID: 1.3.6.1.5.2.3.5 |
| | DER: 06 07 2B 06 01 05 02 03 05 |
| | Comments: RFC 4556 |
+-------+---------------------------------------------------------+
| 12 | Name: SSH Client |
| | Identifiers: id-kp-secureShellClient |
| | OID: 1.3.6.1.5.5.7.3.21 |
| | DER: 06 08 2B 06 01 05 05 07 03 15 |
| | Comments: RFC 6187 |
+-------+---------------------------------------------------------+
| 13 | Name: SSH Server |
| | Identifiers: id-kp-secureShellServer |
| | OID: 1.3.6.1.5.5.7.3.22 |
| | DER: 06 08 2B 06 01 05 05 07 03 16 |
| | Comments: RFC 6187 |
+-------+---------------------------------------------------------+
| 14 | Name: Bundle Security |
| | Identifiers: id-kp-bundleSecurity |
| | OID: 1.3.6.1.5.5.7.3.35 |
| | DER: 06 08 2B 06 01 05 05 07 03 23 |
| | Comments: RFC 9174 |
+-------+---------------------------------------------------------+
| 15 | Name: CMC Certification Authority |
| | Identifiers: id-kp-cmcCA |
| | OID: 1.3.6.1.5.5.7.3.27 |
| | DER: 06 08 2B 06 01 05 05 07 03 1B |
| | Comments: RFC 6402 |
+-------+---------------------------------------------------------+
| 16 | Name: CMC Registration Authority |
| | Identifiers: id-kp-cmcRA |
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| | OID: 1.3.6.1.5.5.7.3.28 |
| | DER: 06 08 2B 06 01 05 05 07 03 1C |
| | Comments: RFC 6402 |
+-------+---------------------------------------------------------+
| 17 | Name: CMC Archive Server |
| | Identifiers: id-kp-cmcArchive |
| | OID: 1.3.6.1.5.5.7.3.29 |
| | DER: 06 08 2B 06 01 05 05 07 03 1D |
| | Comments: RFC 6402 |
+-------+---------------------------------------------------------+
| 18 | Name: CMC Key Generation Authority |
| | Identifiers: id-kp-cmKGA |
| | OID: 1.3.6.1.5.5.7.3.32 |
| | DER: 06 08 2B 06 01 05 05 07 03 20 |
| | Comments: RFC 9480 |
+-------+---------------------------------------------------------+
| 19 | Name: Certificate Transparency |
| | Identifiers: |
| | OID: 1.3.6.1.4.1.11129.2.4.4 |
| | DER: 06 0A 2B 06 01 04 01 D6 79 02 04 04 |
| | Comments: RFC 6962 |
+-------+---------------------------------------------------------+
| 20 | Name: Wi-SUN FAN Device |
| | Identifiers: id-kp-wisun-fan-device |
| | OID: 1.3.6.1.4.1.45605.1 |
| | DER: 06 09 2B 06 01 04 01 82 E4 25 01 |
| | Comments: |
+-------+---------------------------------------------------------+
Figure 16: C509 Extended Key Usages
8.13. C509 General Names Registry
IANA has created a new registry titled "C509 General Names Registry"
under the registry group "CBOR Encoded X.509 (C509) Parameters". The
fields of the registry are Value, Name, Comments, GeneralNameValue,
and Reference, where Value is an integer, and the other columns are
text strings. The fields Name and GeneralNameValue are mandatory.
For values in the interval [-24, 23] the registration procedure is
"IETF Review with Expert Review". For all other values the
registration procedure is "Expert Review". The initial contents of
the registry are:
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+-------+-----------------------------------------------------------+
| Value | General Names |
+=======+===========================================================+
| -3 | Name: otherName with MACAddress |
| | Comments: TBD92(Use RFC I-D-lamps-macaddress-on) |
| | id-on-MACAddress |
| | (1.3.6.1.5.5.7.8.12) |
| | 06 08 2B 06 01 05 05 07 08 0C |
| | GeneralNameValue: bytes |
+-------+-----------------------------------------------------------+
| -2 | Name: otherName with SmtpUTF8Mailbox |
| | Comments: RFC 8398 |
| | id-on-SmtpUTF8Mailbox |
| | (1.3.6.1.5.5.7.8.9) |
| | 06 08 2B 06 01 05 05 07 08 09 |
| | GeneralNameValue: text |
+-------+-----------------------------------------------------------+
| -1 | Name: otherName with hardwareModuleName |
| | Comments: RFC 4108 |
| | id-on-hardwareModuleName |
| | (1.3.6.1.5.5.7.8.4) |
| | 06 08 2B 06 01 05 05 07 08 04 |
| | GeneralNameValue: [ ~oid, bytes ] |
+-------+-----------------------------------------------------------+
| 0 | Name: otherName |
| | Comments: RFC 5280 |
| | GeneralNameValue: [ ~oid, bytes ] |
+-------+-----------------------------------------------------------+
| 1 | Name: rfc822Name |
| | Comments: RFC 5280 |
| | GeneralNameValue: text |
+-------+-----------------------------------------------------------+
| 2 | Name: dNSName |
| | Comments: RFC 5280 |
| | GeneralNameValue: text |
+-------+-----------------------------------------------------------+
| 4 | Name: directoryName |
| | Comments: RFC 5280 |
| | GeneralNameValue: Name |
+-------+-----------------------------------------------------------+
| 6 | Name: uniformResourceIdentifier |
| | Comments: RFC 5280 |
| | GeneralNameValue: text |
+-------+-----------------------------------------------------------+
| 7 | Name: iPAddress |
| | Comments: RFC 5280 |
| | GeneralNameValue: bytes |
+-------+-----------------------------------------------------------+
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| 8 | Name: registeredID |
| | Comments RFC 5280 |
| | GeneralNameValue: ~oid |
+-------+-----------------------------------------------------------+
Figure 17: C509 General Names
8.14. C509 Signature Algorithms Registry
IANA has created a new registry titled "C509 Signature Algorithms"
under the registry group "CBOR Encoded X.509 (C509) Parameters". The
registry includes both signature algorithms and non-signature proof-
of-possession algorithms. The fields of the registry are Value,
Name, Identifiers, OID, Parameters, DER, Comments, and Reference,
where Value is an integer, and the other columns are text strings.
The fields Name, OID, Parameters, and DER are mandatory. Alignment
with the value of public key algorithm MUST be considered, see
instruction in Section 8.15. For values in the interval [-24, 23]
the registration procedure is "IETF Review with Expert Review". For
all other values the registration procedure is "Expert Review". The
initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | X.509 Signature Algorithms |
+=======+===========================================================+
| -256 | Name: RSASSA-PKCS1-v1_5 with SHA-1 |
| | Identifiers: sha1-with-rsa-signature, |
| | sha1WithRSAEncryption, |
| | sha-1WithRSAEncryption |
| | OID: 1.2.840.113549.1.1.5 |
| | Parameters: NULL |
| | DER: 30 0D 06 09 2A 86 48 86 F7 0D 01 01 05 05 00 |
| | Comments: Don't use |
+-------+-----------------------------------------------------------+
| -255 | Name: ECDSA with SHA-1 |
| | Identifiers: ecdsa-with-SHA1 |
| | OID: 1.2.840.10045.4.1 |
| | Parameters: Absent |
| | DER: 30 09 06 07 2A 86 48 CE 3D 04 01 |
| | Comments: Don't use. See Section 3.2.2. |
+-------+-----------------------------------------------------------+
| 0 | Name: ECDSA with SHA-256 |
| | Identifiers: ecdsa-with-SHA256 |
| | OID: 1.2.840.10045.4.3.2 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 86 48 CE 3D 04 03 02 |
| | Comments: See Section 3.2.2. |
+-------+-----------------------------------------------------------+
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| 1 | Name: ECDSA with SHA-384 |
| | Identifiers: ecdsa-with-SHA384 |
| | OID: 1.2.840.10045.4.3.3 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 86 48 CE 3D 04 03 03 |
| | Comments: See Section 3.2.2. |
+-------+-----------------------------------------------------------+
| 2 | Name: ECDSA with SHA-512 |
| | Identifiers: ecdsa-with-SHA512 |
| | OID: 1.2.840.10045.4.3.4 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 86 48 CE 3D 04 03 04 |
| | Comments: See Section 3.2.2. |
+-------+-----------------------------------------------------------+
| 3 | Name: ECDSA with SHAKE128 |
| | Identifiers: id-ecdsa-with-shake128 |
| | OID: 1.3.6.1.5.5.7.6.32 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 20 |
| | Comments: See Section 3.2.2. |
+-------+-----------------------------------------------------------+
| 4 | Name: ECDSA with SHAKE256 |
| | Identifiers: id-ecdsa-with-shake256 |
| | OID: 1.3.6.1.5.5.7.6.33 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 21 |
| | Comments: See Section 3.2.2. |
+-------+-----------------------------------------------------------+
| 5 | Name: Unsigned |
| | Identifiers: id-alg-unsigned |
| | OID: 1.3.6.1.5.5.7.6.36 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 24 |
| | Comments: bytes of size 0 |
+-------+-----------------------------------------------------------+
| 8 | Name: SM2 with SM3 |
| | Identifiers: sm2-with-sm3 |
| | OID: 1.2.156.10197.1.501 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 81 1C CF 55 01 83 75 |
| | Comments: See Section 3.2.2. |
+-------+-----------------------------------------------------------+
| 12 | Name: Ed25519 |
| | Identifiers: id-Ed25519, id-EdDSA25519 |
| | OID: 1.3.101.112 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 70 |
| | Comments: |
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+-------+-----------------------------------------------------------+
| 13 | Name: Ed448 |
| | Identifiers: id-Ed448, id-EdDSA448 |
| | OID: 1.3.101.113 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 71 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 14 | Name: PoP with SHA-256 and HMAC-SHA256 |
| | Identifiers: sa-ecdhPop-sha256-hmac-sha256 |
| | OID: 1.3.6.1.5.5.7.6.26 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1A |
| | Comments: Proof-of-possession algorithm, indexed with |
| | KDF and MAC, see RFC 6955. Requires |
| | recipient's public static Diffie-Hellman key |
+-------+-----------------------------------------------------------+
| 15 | Name: PoP with SHA-384 and HMAC-SHA384 |
| | Identifiers: sa-ecdhPop-sha384-hmac-sha384 |
| | OID: 1.3.6.1.5.5.7.6.27 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1B |
| | Comments: Proof-of-possession algorithm, indexed with |
| | KDF and MAC, see RFC 6955. Requires |
| | recipient's public static Diffie-Hellman key |
+-------+-----------------------------------------------------------+
| 16 | Name: PoP with SHA-512 and HMAC-SHA512 |
| | Identifiers: sa-ecdhPop-sha512-hmac-sha512 |
| | OID: 1.3.6.1.5.5.7.6.28 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1C |
| | Comments: Proof-of-possession algorithm, indexed with |
| | KDF and MAC, see RFC 6955. Requires |
| | recipient's public static Diffie-Hellman key |
+-------+-----------------------------------------------------------+
| 23 | Name: RSASSA-PKCS1-v1_5 with SHA-256 |
| | Identifiers: sha256WithRSAEncryption |
| | OID: 1.2.840.113549.1.1.11 |
| | Parameters: NULL |
| | DER: 30 0B 06 09 2A 86 48 86 F7 0D 01 01 0B 05 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 24 | Name: RSASSA-PKCS1-v1_5 with SHA-384 |
| | Identifiers: sha384WithRSAEncryption |
| | OID: 1.2.840.113549.1.1.12 |
| | Parameters: NULL |
| | DER: 30 0B 06 09 2A 86 48 86 F7 0D 01 01 0C 05 00 |
| | Comments: |
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+-------+-----------------------------------------------------------+
| 25 | Name: RSASSA-PKCS1-v1_5 with SHA-512 |
| | Identifiers: sha512WithRSAEncryption |
| | OID: 1.2.840.113549.1.1.13 |
| | Parameters: NULL |
| | DER: 30 0B 06 09 2A 86 48 86 F7 0D 01 01 0D 05 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 26 | Name: RSASSA-PSS with SHA-256 |
| | Identifiers: rsassa-pss, id-RSASSA-PSS |
| | OID: 1.2.840.113549.1.1.10 |
| | Parameters: SHA-256, MGF-1 with SHA-256, saltLength = 32 |
| | DER: 30 41 06 09 2A 86 48 86 F7 0D 01 01 0A 30 34 |
| | A0 0F 30 0D 06 09 60 86 48 01 65 03 04 02 01 |
| | 05 00 A1 1C 30 1A 06 09 2A 86 48 86 F7 0D 01 |
| | 01 08 30 0D 06 09 60 86 48 01 65 03 04 02 01 |
| | 05 00 a2 03 02 01 20 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 27 | Name: RSASSA-PSS with SHA-384 |
| | Identifiers: rsassa-pss, id-RSASSA-PSS |
| | OID: 1.2.840.113549.1.1.10 |
| | Parameters: SHA-384, MGF-1 with SHA-384, saltLength = 48 |
| | DER: 30 41 06 09 2A 86 48 86 F7 0D 01 01 0A 30 34 |
| | A0 0F 30 0D 06 09 60 86 48 01 65 03 04 02 02 |
| | 05 00 A1 1C 30 1A 06 09 2A 86 48 86 F7 0D 01 |
| | 01 08 30 0D 06 09 60 86 48 01 65 03 04 02 02 |
| | 05 00 A2 03 02 01 30 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 28 | Name: RSASSA-PSS with SHA-512 |
| | Identifiers: rsassa-pss, id-RSASSA-PSS |
| | OID: 1.2.840.113549.1.1.10 |
| | Parameters: SHA-512, MGF-1 with SHA-512, saltLength = 64 |
| | DER: 30 41 06 09 2A 86 48 86 F7 0D 01 01 0A 30 34 |
| | A0 0F 30 0D 06 09 60 86 48 01 65 03 04 02 03 |
| | 05 00 A1 1C 30 1A 06 09 2A 86 48 86 F7 0D 01 |
| | 01 08 30 0D 06 09 60 86 48 01 65 03 04 02 03 |
| | 05 00 A2 03 02 01 40 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 29 | Name: RSASSA-PSS with SHAKE128 |
| | Identifiers: id-RSASSA-PSS-SHAKE128 |
| | OID: 1.3.6.1.5.5.7.6.30 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1E |
| | Comments: |
+-------+-----------------------------------------------------------+
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| 30 | Name: RSASSA-PSS with SHAKE256 |
| | Identifiers: id-RSASSA-PSS-SHAKE256 |
| | OID: 1.3.6.1.5.5.7.6.31 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1F |
| | Comments: |
+-------+-----------------------------------------------------------+
Figure 18: C509 Signature Algorithms
8.15. C509 Public Key Algorithms Registry
IANA has created a new registry titled "C509 Public Key Algorithms"
under the registry group "CBOR Encoded X.509 (C509) Parameters". The
fields of the registry are Value, Name, Identifiers, OID, Parameters,
DER, Comments, and Reference, where Value is an integer, and the
other columns are text strings. The fields Name, OID, Parameters,
and DER are mandatory. If the public key can only be used with one
signature algorithm and the OID of the public key algorithm is the
same as the signature algorithm, then the value MUST be chosen equal
to the value of signature algorithm, see Section 8.14. For values in
the interval [-24, 23] the registration procedure is "IETF Review
with Expert Review". For all other values the registration procedure
is "Expert Review". The initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | X.509 Public Key Algorithms |
+=======+===========================================================+
| 0 | Name: RSA |
| | Identifiers: rsaEncryption |
| | OID: 1.2.840.113549.1.1.1 |
| | Parameters: NULL |
| | DER: 30 0d 06 09 2a 86 48 86 f7 0d 01 01 01 05 00 |
| | Comments: Compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 1 | Name: EC Public Key (Weierstrass) with secp256r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = secp256r1 (1.2.840.10045.3.1.7) |
| | DER: 30 13 06 07 2A 86 48 CE 3D 02 01 06 08 2A 86 |
| | 48 CE 3D 03 01 07 |
| | Comments: Compressed subjectPublicKey |
| | Also known as P-256, ansip256r1, prime256v1 |
+-------+-----------------------------------------------------------+
| 2 | Name: EC Public Key (Weierstrass) with secp384r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = secp384r1 (1.3.132.0.34) |
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| | DER: 30 10 06 07 2A 86 48 CE 3D 02 01 06 05 2B 81 |
| | 04 00 22 |
| | Comments: Compressed subjectPublicKey |
| | Also known as P-384, ansip384r1 |
+-------+-----------------------------------------------------------+
| 3 | Name: EC Public Key (Weierstrass) with secp521r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = secp521r1 (1.3.132.0.35) |
| | DER: 30 10 06 07 2A 86 48 CE 3D 02 01 06 05 2B 81 |
| | 04 00 23 |
| | Comments: Compressed subjectPublicKey |
| | Also known as P-521, ansip521r1 |
+-------+-----------------------------------------------------------+
| 6 | Name: EC Public Key (Weierstrass) with |
| | sm2p256v1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = sm2p256v1 |
| | (1.2.156.10197.1.301) |
| | DER: 30 13 06 07 2A 86 48 CE 3D 02 01 06 08 2A 81 |
| | 1C CF 55 01 82 2D |
| | Comments: Compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 8 | Name: X25519 (Montgomery) |
| | Identifiers: id-X25519 |
| | OID: 1.3.101.110 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 6E |
| | Comments: |
+-------+-----------------------------------------------------------+
| 9 | Name: X448 (Montgomery) |
| | Identifiers: id-X448 |
| | OID: 1.3.101.111 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 6F |
| | Comments: |
+-------+-----------------------------------------------------------+
| 12 | Name: Ed25519 (Twisted Edwards) |
| | Identifiers: id-Ed25519, id-EdDSA25519 |
| | OID: 1.3.101.112 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 70 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 13 | Name: Ed448 (Edwards) |
| | Identifiers: id-Ed448, id-EdDSA448 |
| | OID: 1.3.101.113 |
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| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 71 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 24 | Name: EC Public Key (Weierstrass) with |
| | brainpoolP256r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = brainpoolP256r1 |
| | (1.3.36.3.3.2.8.1.1.7) |
| | DER: 30 14 06 07 2A 86 48 CE 3D 02 01 06 09 2B 24 |
| | 03 03 02 08 01 01 07 |
| | Comments: Compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 25 | Name: EC Public Key (Weierstrass) with |
| | brainpoolP384r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = brainpoolP384r1 |
| | (1.3.36.3.3.2.8.1.1.11) |
| | DER: 30 14 06 07 2A 86 48 CE 3D 02 01 06 09 2B 24 |
| | 03 03 02 08 01 01 0B |
| | Comments: Compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 26 | Name: EC Public Key (Weierstrass) with |
| | brainpoolP512r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = brainpoolP512r1 |
| | (1.3.36.3.3.2.8.1.1.13) |
| | DER: 30 14 06 07 2A 86 48 CE 3D 02 01 06 09 2B 24 |
| | 03 03 02 08 01 01 0D |
| | Comments: Compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 27 | Name: EC Public Key (Weierstrass) with |
| | FRP256v1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = FRP256v1 |
| | (1.2.250.1.223.101.256.1) |
| | DER: 30 15 06 07 2A 86 48 CE 3D 02 01 06 0A 2A 81 |
| | 7A 01 81 5F 65 82 00 01 |
| | Comments: Compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
Figure 19: C509 Public Key Algorithms
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8.15.1. Suitability of different public key algorithms for use within
IoT scenarios
The public key algorithms registry Section 8.15 specifies a number of
algorithms, not all which are suitable for usage with constrained
devices. RSA requires large keys and large signature sizes compared
to elliptic curve cryptography (ECC), which together with resource-
efficient implementations of named elliptic curves (Montgomery,
Edwards and Weierstrass curves) make them suitable candidates for IoT
public key usage.
8.16. COSE Header Parameters Registry
IANA is requested to assign the entries in Table 1 to the "COSE
Header Parameters" registry in the registry group "CBOR Object
Signing and Encryption (COSE)" with this document as reference.
8.17. COSE Header Algorithm Parameters Registry
IANA is requested to assign the entries in Table 2 to the "COSE
Header Algorithm Parameters" registry in the registry group "CBOR
Object Signing and Encryption (COSE)" with this document as
reference.
8.18. Media Type Application Registry
IANA is requested to assign the following entries in to the
"application" registry in the registry group "Media Types" with this
document as reference.
8.18.1. Media Type application/cose-c509-cert
When the application/cose-c509-cert media type is used, the data is a
COSE_C509 structure. If the parameter "usage" is set to "chain",
this sequence indicates a certificate chain.
Type name: application
Subtype name: cose-c509-cert
Required parameters: N/A
Optional parameters: usage
* Can be absent to provide no further information about the intended
meaning of the order in the CBOR sequence of certificates.
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* Can be set to "chain" to indicate that the sequence of data items
is to be interpreted as a certificate chain.
Encoding considerations: binary
Security considerations: See the Security Considerations section of
[[this document]].
Interoperability considerations: N/A
Published specification: [[this document]]
Applications that use this media type: Applications that employ COSE
and use C509 as a certificate type.
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): TBD8, TBD6
* 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
8.18.2. Media Type application/cose-c509-pkcs10
When the application/cose-c509-pkcs10 media type is used, the data is
a C509CertificationRequest structure.
Type name: application
Subtype name: cose-c509-pkcs10
Required parameters: N/A
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Optional parameters: N/A
Encoding considerations: binary
Security considerations: See the Security Considerations section of
[[this document]].
Interoperability considerations: N/A
Published specification: [[this document]]
Applications that use this media type: Applications that employ COSE
and C509 Certification Request.
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): TBD9
* 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
8.18.3. Media Type application/cose-c509-crtemplate
When the application/cose-c509-crtemplate media type is used, the
data is a C509CertificationRequestTemplate structure.
Type name: application
Subtype name: cose-c509-crtemplate
Required parameters: N/A
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Optional parameters: N/A
Encoding considerations: binary
Security considerations: See the Security Considerations section of
[[this document]].
Interoperability considerations: N/A
Published specification: [[this document]]
Applications that use this media type: Applications that employ COSE
and C509 Certification Request.
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): TBD18
* 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
8.18.4. Media Type application/cose-c509-privkey
When the application/cose-c509-privkey media type is used, the data
is a C509PrivateKey structure.
Type name: application
Subtype name: cose-c509-privkey
Required parameters: N/A
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Optional parameters: usage
Encoding considerations: binary
Security considerations: See the Security Considerations section of
[[this document]].
Interoperability considerations: N/A
Published specification: [[this document]]
Applications that use this media type: Applications that employ COSE
and use C509 as a certificate type.
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): TBD12
* 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
8.18.5. Media Type application/cose-c509-pem
When the application/cose-c509-pem media type is used, the data is a
C509PEM structure.
Type name: application
Subtype name: cose-c509-pem
Required parameters: N/A
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Optional parameters: usage
Encoding considerations: binary
Security considerations: See the Security Considerations section of
[[this document]].
Interoperability considerations: N/A
Published specification: [[this document]]
Applications that use this media type: Applications that employ COSE
and use C509 as a certificate type.
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): TBD13
* 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
8.18.6. Media Type application/cose-certhash
When the application/cose-certhash media type is used, the data is a
COSE_CertHash structure, see [RFC9360].
Type name: application
Subtype name: cose-certhash
Required parameters: N/A
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Optional parameters: usage
* Can be absent to provide no further information about what the
hash value is calculated over.
* Can be set to "c509" to indicate that the hash value is calculated
over a C509 certificate, see Section 3.4.
Encoding considerations: binary
Security considerations: See the Security Considerations section of
[RFC9360].
Interoperability considerations: N/A
Published specification: [[this document]]
Applications that use this media type: Applications that employ COSE
and use X.509 or C509 as certificate type.
Fragment identifier considerations: N/A
Additional information:
* Deprecated alias names for this type: N/A
* Magic number(s): N/A
* File extension(s): N/A
* 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
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8.19. CoAP Content-Formats Registry
IANA is requested to add entries for "application/cose-c509-cert",
"application/cose-c509-pkcs10", "application/cose-c509-crtemplate",
"application/cose-c509-privkey" and "application/cose-c509-pem" to
the "CoAP Content-Formats" registry in the registry group
"Constrained RESTful Environments (CoRE) Parameters". A dedicated
Content-Format ID is requested for the "application/cose-c509-cert"
media type in the case when the parameter "usage" is set to "chain",
see Section 8.18.1.
IANA is requested to add entries for "application/cose-certhash" to
the "CoAP Content-Formats" registry in the registry group
"Constrained RESTful Environments (CoRE) Parameters". A dedicated
Content-Format ID is requested in the case when the parameter "usage"
is set to "c509", see Section 8.18.6.
IANA is requested to add entries for "application/cbor" to the "CoAP
Content-Formats" registry in the registry group "Constrained RESTful
Environments (CoRE) Parameters", in the case when the encoding is a
CBOR text string containing a URI, see [RFC3986].
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+----------------------+---------+-----------+-------+------------+
| Content | Content | Media | ID | Reference |
| Format | Coding | Type | | |
+======================+=========+===========+=======+============+
| application/ | - | [[link | TBD3 | [[this |
| cose-c509-cert | | to 8.18]] | | document]] |
+----------------------+---------+-----------+-------+------------+
| application/ | | [[link | | [[this |
| cose-c509-cert; | - | to 8.18]] | TBD15 | document]] |
| usage = chain | | | | |
+----------------------+---------+-----------+-------+------------+
| application/ | - | [[link | TBD4 | [[this |
| cose-c509-pkcs10 | | to 8.18]] | | document]] |
+----------------------+---------+-----------+-------+------------+
| application/ | - | [[link | TBD19 | [[this |
| cose-c509-crtemplate | | to 8.18]] | | document]] |
+----------------------+---------+-----------+-------+------------+
| application/ | - | [[link | TBD10 | [[this |
| cose-c509-privkey | | to 8.18]] | | document]] |
+----------------------+---------+-----------+-------+------------+
| application/ | - | [[link | TBD11 | [[this |
| cose-c509-pem | | to 8.18]] | | document]] |
+----------------------+---------+-----------+-------+------------+
| application/ | - | [[link | TBD16 | [[this |
| cose-certhash | | to 8.18]] | | document]] |
+----------------------+---------+-----------+-------+------------+
| application/ | | [[link | | [[this |
| cose-certhash; | - | to 8.18]] | TBD17 | document]] |
| usage = c509 | | | | |
+----------------------+---------+-----------+-------+------------+
Figure 20: CoAP Content-Format IDs
8.20. TLS Certificate Types Registry
This document registers the following entry in the "TLS Certificate
Types" registry in the registry group "Transport Layer Security (TLS)
Extensions". The new certificate type can be used with additional
TLS certificate compression [RFC8879]. For TLS 1.3, the C509
certificate type is defined as a new case in the CertificateEntry
struct specified in Section 4.4.2 of [RFC8446]:
case C509:
opaque c509_data<1..2^24-1>;
where c509_data is the CBOR sequence ~C509Certificate (an unwrapped
C509Certificate). For TLS 1.2 the same construction is applied with
a similar union type defined for the Certificate struct in
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Section 7.4.2 of [RFC5246]. Note that, similar to COSE_C509, the TLS
handshake contains the length of each certificate. The TLS
extensions client_certificate_type and server_certificate_type
[RFC7250] are used to negotiate the use of C509.
+-------+------------------+-------------+--------------------------+
| Value | Name | Recommended | Comment |
+=======+==================+=============+==========================+
| TBD5 | C509 Certificate | N | |
+-------+------------------+-------------+--------------------------+
8.21. TLSA Selectors Registry
This document registers the following entry in the "TLSA Selectors"
registry in the registry group "DNS-Based Authentication of Named
Entities (DANE) Parameters". The C509 certificate data,
C509CertData, is defined in Section 3.4.
+-------+---------+------------------------+-------------------+
| Value | Acronym | Short Description | Reference |
+=======+=========+========================+===================+
| TBD7 | C509 | C509 certificate data | [[this document]] |
+-------+---------+------------------------+-------------------+
The TLSA selectors registry defined in [RFC6698] originally only
applied to PKIX [RFC5280] certificates in DER encoding. This
specification updates [RFC6698] to accept the use of C509
certificates.
8.22. EDHOC Authentication Credential Types Registry
This document registers the following entry in the "EDHOC
Authentication Credential Types" registry in the registry group
"Ephemeral Diffie-Hellman Over COSE (EDHOC)". This is useful to
identify C509 certificates as a supported authentication credential
type to use with EDHOC [RFC9528], for example, during discovery of
EDHOC resources, see [RFC9668].
+-------+----------------------+-------------------+
| Value | Description | Reference |
+=======+======================+===================+
| 3 | C509 certificate | [[this document]] |
+-------+----------------------+-------------------+
8.23. Relative Distinguished Name Attribute
This document regists the following entry in the "SMI Security for
PKIX Relative Distinguished Name Attribute" registry [RFC7299]:
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+---------+----------------------+-------------------+
| Decimal | Description | Reference |
+=========+======================+===================+
| TBD30 | id-rdna-c509Name | [[this document]] |
+---------+----------------------+-------------------+
9. References
9.1. Normative References
[I-D.ietf-lamps-macaddress-on]
Housley, R., Bonnell, C., Mandel, J., Okubo, T., and M.
StJohns, "Media Access Control (MAC) Addresses in X.509
Certificates", Work in Progress, Internet-Draft, draft-
ietf-lamps-macaddress-on-07, 12 March 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
macaddress-on-07>.
[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>.
[RFC2985] Nystrom, M. and B. Kaliski, "PKCS #9: Selected Object
Classes and Attribute Types Version 2.0", RFC 2985,
DOI 10.17487/RFC2985, November 2000,
<https://www.rfc-editor.org/rfc/rfc2985>.
[RFC2986] Nystrom, M. and B. Kaliski, "PKCS #10: Certification
Request Syntax Specification Version 1.7", RFC 2986,
DOI 10.17487/RFC2986, November 2000,
<https://www.rfc-editor.org/rfc/rfc2986>.
[RFC3779] Lynn, C., Kent, S., and K. Seo, "X.509 Extensions for IP
Addresses and AS Identifiers", RFC 3779,
DOI 10.17487/RFC3779, June 2004,
<https://www.rfc-editor.org/rfc/rfc3779>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, DOI 10.17487/RFC3986, January 2005,
<https://www.rfc-editor.org/rfc/rfc3986>.
[RFC4108] Housley, R., "Using Cryptographic Message Syntax (CMS) to
Protect Firmware Packages", RFC 4108,
DOI 10.17487/RFC4108, August 2005,
<https://www.rfc-editor.org/rfc/rfc4108>.
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[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/rfc/rfc5246>.
[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>.
[RFC5958] Turner, S., "Asymmetric Key Packages", RFC 5958,
DOI 10.17487/RFC5958, August 2010,
<https://www.rfc-editor.org/rfc/rfc5958>.
[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>.
[RFC6698] Hoffman, P. and J. Schlyter, "The DNS-Based Authentication
of Named Entities (DANE) Transport Layer Security (TLS)
Protocol: TLSA", RFC 6698, DOI 10.17487/RFC6698, August
2012, <https://www.rfc-editor.org/rfc/rfc6698>.
[RFC6962] Laurie, B., Langley, A., and E. Kasper, "Certificate
Transparency", RFC 6962, DOI 10.17487/RFC6962, June 2013,
<https://www.rfc-editor.org/rfc/rfc6962>.
[RFC7030] Pritikin, M., Ed., Yee, P., Ed., and D. Harkins, Ed.,
"Enrollment over Secure Transport", RFC 7030,
DOI 10.17487/RFC7030, October 2013,
<https://www.rfc-editor.org/rfc/rfc7030>.
[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>.
[RFC7250] Wouters, P., Ed., Tschofenig, H., Ed., Gilmore, J.,
Weiler, S., and T. Kivinen, "Using Raw Public Keys in
Transport Layer Security (TLS) and Datagram Transport
Layer Security (DTLS)", RFC 7250, DOI 10.17487/RFC7250,
June 2014, <https://www.rfc-editor.org/rfc/rfc7250>.
[RFC7299] Housley, R., "Object Identifier Registry for the PKIX
Working Group", RFC 7299, DOI 10.17487/RFC7299, July 2014,
<https://www.rfc-editor.org/rfc/rfc7299>.
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[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>.
[RFC8295] Turner, S., "EST (Enrollment over Secure Transport)
Extensions", RFC 8295, DOI 10.17487/RFC8295, January 2018,
<https://www.rfc-editor.org/rfc/rfc8295>.
[RFC8360] Huston, G., Michaelson, G., Martinez, C., Bruijnzeels, T.,
Newton, A., and D. Shaw, "Resource Public Key
Infrastructure (RPKI) Validation Reconsidered", RFC 8360,
DOI 10.17487/RFC8360, April 2018,
<https://www.rfc-editor.org/rfc/rfc8360>.
[RFC8398] Melnikov, A., Ed. and W. Chuang, Ed., "Internationalized
Email Addresses in X.509 Certificates", RFC 8398,
DOI 10.17487/RFC8398, May 2018,
<https://www.rfc-editor.org/rfc/rfc8398>.
[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>.
[RFC9052] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Structures and Process", STD 96, RFC 9052,
DOI 10.17487/RFC9052, August 2022,
<https://www.rfc-editor.org/rfc/rfc9052>.
[RFC9090] Bormann, C., "Concise Binary Object Representation (CBOR)
Tags for Object Identifiers", RFC 9090,
DOI 10.17487/RFC9090, July 2021,
<https://www.rfc-editor.org/rfc/rfc9090>.
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[RFC9277] Richardson, M. and C. Bormann, "On Stable Storage for
Items in Concise Binary Object Representation (CBOR)",
RFC 9277, DOI 10.17487/RFC9277, August 2022,
<https://www.rfc-editor.org/rfc/rfc9277>.
[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>.
[RFC9542] Eastlake 3rd, D., Abley, J., and Y. Li, "IANA
Considerations and IETF Protocol and Documentation Usage
for IEEE 802 Parameters", BCP 141, RFC 9542,
DOI 10.17487/RFC9542, April 2024,
<https://www.rfc-editor.org/rfc/rfc9542>.
[RFC9549] Housley, R., "Internationalization Updates to RFC 5280",
RFC 9549, DOI 10.17487/RFC9549, March 2024,
<https://www.rfc-editor.org/rfc/rfc9549>.
[RFC9668] Palombini, F., Tiloca, M., Höglund, R., Hristozov, S., and
G. Selander, "Using Ephemeral Diffie-Hellman Over COSE
(EDHOC) with the Constrained Application Protocol (CoAP)
and Object Security for Constrained RESTful Environments
(OSCORE)", RFC 9668, DOI 10.17487/RFC9668, November 2024,
<https://www.rfc-editor.org/rfc/rfc9668>.
[RFC9883] Housley, R., "An Attribute for Statement of Possession of
a Private Key", RFC 9883, DOI 10.17487/RFC9883, October
2025, <https://www.rfc-editor.org/rfc/rfc9883>.
[SECG] "Elliptic Curve Cryptography, Standards for Efficient
Cryptography Group, ver. 2", 2009,
<https://secg.org/sec1-v2.pdf>.
[Wi-SUN] "Wi-SUN Alliance", n.d., <https://wi-sun.org>.
[X.501] "Information Technology - Open Systems Interconnection -
The Directory: Models, ITU-T X.501", December 2019,
<https://www.itu.int/rec/T-REC-X.501/en>.
[X.520] "Information Technology - Open Systems Interconnection -
The Directory: Selected attribute types", October 2019,
<https://www.itu.int/rec/T-REC-X.520/en>.
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[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>.
9.2. Informative References
[CAB-Code] CA/Browser Forum, "CA/Browser Forum, "Baseline
Requirements for the Issuance and Management of Publicly-
Trusted Code Signing Certificates Version 3.8.0"", August
2024, <https://cabforum.org/baseline-requirements-code-
signing/>.
[CAB-TLS] CA/Browser Forum, "CA/Browser Forum, "Baseline
Requirements for the Issuance and Management of Publicly-
Trusted Certificates Version 2.1.4"", March 2025,
<https://cabforum.org/baseline-requirements-documents/>.
[CborMe] Bormann, C., "CBOR Playground", May 2018,
<https://cbor.me/>.
[GSMA-eUICC]
GSMA, "GSMA eUICC PKI Certificate Policy Version 2.2",
January 2025, <https://www.gsma.com/solutions-and-
impact/technologies/esim/wp-content/uploads/2025/01/
SGP.14-v2.2.pdf>.
[GSMA-SGP.22]
"GSMA RSP Technial Specification Version 3.1 Final",
December 2023, <https://www.gsma.com/solutions-and-
impact/technologies/esim/wp-content/uploads/2023/12/
SGP.22-v3.1.pdf>.
[I-D.ietf-lamps-rfc7030-csrattrs]
Richardson, M., Friel, O., von Oheimb, D., and D. Harkins,
"Clarification and enhancement of RFC7030 CSR Attributes
definition", Work in Progress, Internet-Draft, draft-ietf-
lamps-rfc7030-csrattrs-23, 28 June 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
rfc7030-csrattrs-23>.
[I-D.ietf-tls-ctls]
Rescorla, E., Barnes, R., Tschofenig, H., and B. M.
Schwartz, "Compact TLS 1.3", Work in Progress, Internet-
Draft, draft-ietf-tls-ctls-10, 17 April 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-tls-
ctls-10>.
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[I-D.ietf-uta-tls13-iot-profile]
Tschofenig, H., Fossati, T., Richardson, M., and D.
Migault, "TLS/DTLS 1.3 Profiles for the Internet of
Things", Work in Progress, Internet-Draft, draft-ietf-uta-
tls13-iot-profile-19, 20 February 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-uta-
tls13-iot-profile-19>.
[IANA-AFI] "Address Family Numbers", n.d.,
<https://www.iana.org/assignments/address-family-numbers/
address-family-numbers.xhtml>.
[IANA-CBOR-TAGS]
IANA, "Concise Binary Object Representation (CBOR) Tags",
n.d., <https://www.iana.org/assignments/cbor-tags/cbor-
tags.xhtml>.
[IANA-SAFI]
"Subsequent Address Family Identifiers (SAFI) Parameters",
n.d., <https://www.iana.org/assignments/safi-namespace/
safi-namespace.xhtml>.
[IEEE-802.1AR]
Institute of Electrical and Electronics Engineers, "IEEE
Standard for Local and metropolitan area networks–Secure
Device Identity", IEEE Standard 802.1AR-2018 , August
2018,
<https://standards.ieee.org/standard/802_1AR-2018.html>.
[RFC1274] Barker, P. and S. Kille, "The COSINE and Internet X.500
Schema", RFC 1274, DOI 10.17487/RFC1274, November 1991,
<https://www.rfc-editor.org/rfc/rfc1274>.
[RFC2247] Kille, S., Wahl, M., Grimstad, A., Huber, R., and S.
Sataluri, "Using Domains in LDAP/X.500 Distinguished
Names", RFC 2247, DOI 10.17487/RFC2247, January 1998,
<https://www.rfc-editor.org/rfc/rfc2247>.
[RFC3161] Adams, C., Cain, P., Pinkas, D., and R. Zuccherato,
"Internet X.509 Public Key Infrastructure Time-Stamp
Protocol (TSP)", RFC 3161, DOI 10.17487/RFC3161, August
2001, <https://www.rfc-editor.org/rfc/rfc3161>.
[RFC6487] Huston, G., Michaelson, G., and R. Loomans, "A Profile for
X.509 PKIX Resource Certificates", RFC 6487,
DOI 10.17487/RFC6487, February 2012,
<https://www.rfc-editor.org/rfc/rfc6487>.
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[RFC6955] Schaad, J. and H. Prafullchandra, "Diffie-Hellman Proof-
of-Possession Algorithms", RFC 6955, DOI 10.17487/RFC6955,
May 2013, <https://www.rfc-editor.org/rfc/rfc6955>.
[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>.
[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>.
[RFC7468] Josefsson, S. and S. Leonard, "Textual Encodings of PKIX,
PKCS, and CMS Structures", RFC 7468, DOI 10.17487/RFC7468,
April 2015, <https://www.rfc-editor.org/rfc/rfc7468>.
[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>.
[RFC7932] Alakuijala, J. and Z. Szabadka, "Brotli Compressed Data
Format", RFC 7932, DOI 10.17487/RFC7932, July 2016,
<https://www.rfc-editor.org/rfc/rfc7932>.
[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>.
[RFC8603] Jenkins, M. and L. Zieglar, "Commercial National Security
Algorithm (CNSA) Suite Certificate and Certificate
Revocation List (CRL) Profile", RFC 8603,
DOI 10.17487/RFC8603, May 2019,
<https://www.rfc-editor.org/rfc/rfc8603>.
[RFC8879] Ghedini, A. and V. Vasiliev, "TLS Certificate
Compression", RFC 8879, DOI 10.17487/RFC8879, December
2020, <https://www.rfc-editor.org/rfc/rfc8879>.
[RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
Multiplexed and Secure Transport", RFC 9000,
DOI 10.17487/RFC9000, May 2021,
<https://www.rfc-editor.org/rfc/rfc9000>.
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[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>.
[RFC9148] van der Stok, P., Kampanakis, P., Richardson, M., and S.
Raza, "EST-coaps: Enrollment over Secure Transport with
the Secure Constrained Application Protocol", RFC 9148,
DOI 10.17487/RFC9148, April 2022,
<https://www.rfc-editor.org/rfc/rfc9148>.
[RFC9190] Preuß Mattsson, J. and M. Sethi, "EAP-TLS 1.3: Using the
Extensible Authentication Protocol with TLS 1.3",
RFC 9190, DOI 10.17487/RFC9190, February 2022,
<https://www.rfc-editor.org/rfc/rfc9190>.
[RFC9191] Sethi, M., Preuß Mattsson, J., and S. Turner, "Handling
Large Certificates and Long Certificate Chains in TLS-
Based EAP Methods", RFC 9191, DOI 10.17487/RFC9191,
February 2022, <https://www.rfc-editor.org/rfc/rfc9191>.
[RFC9528] Selander, G., Preuß Mattsson, J., and F. Palombini,
"Ephemeral Diffie-Hellman Over COSE (EDHOC)", RFC 9528,
DOI 10.17487/RFC9528, March 2024,
<https://www.rfc-editor.org/rfc/rfc9528>.
[SP-800-56A]
Barker, E., Chen, L., Roginsky, A., Vassilev, A., and R.
Davis, "Recommendation for Pair-Wise Key-Establishment
Schemes Using Discrete Logarithm Cryptography",
NIST Special Publication 800-56A Revision 3, April 2018,
<https://doi.org/10.6028/NIST.SP.800-56Ar3>.
[X.509-IoT]
Forsby, F., Furuhed, M., Papadimitratos, P., and S. Raza,
"Lightweight X.509 Digital Certificates for the Internet
of Things.", Springer, Cham. Lecture Notes of the
Institute for Computer Sciences, Social Informatics and
Telecommunications Engineering, vol 242., July 2018,
<https://doi.org/10.1007/978-3-319-93797-7_14>.
Appendix A. C509 Certificate Examples
A.1. Example: RFC 7925 profiled X.509 Certificate
Example of [RFC7925] profiled X.509 certificate parsed with OpenSSL.
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Certificate:
Data:
Version: 3 (0x2)
Serial Number: 128269 (0x1f50d)
Signature Algorithm: ecdsa-with-SHA256
Issuer: CN=RFC test CA
Validity
Not Before: Jan 1 00:00:00 2023 GMT
Not After : Jan 1 00:00:00 2026 GMT
Subject: CN=01-23-45-FF-FE-67-89-AB
Subject Public Key Info:
Public Key Algorithm: id-ecPublicKey
Public-Key: (256 bit)
pub:
04:b1:21:6a:b9:6e:5b:3b:33:40:f5:bd:f0:2e:69:
3f:16:21:3a:04:52:5e:d4:44:50:b1:01:9c:2d:fd:
38:38:ab:ac:4e:14:d8:6c:09:83:ed:5e:9e:ef:24:
48:c6:86:1c:c4:06:54:71:77:e6:02:60:30:d0:51:
f7:79:2a:c2:06
ASN1 OID: prime256v1
NIST CURVE: P-256
X509v3 extensions:
X509v3 Key Usage:
Digital Signature
Signature Algorithm: ecdsa-with-SHA256
30:46:02:21:00:d4:32:0b:1d:68:49:e3:09:21:9d:30:03:7e:
13:81:66:f2:50:82:47:dd:da:e7:6c:ce:ea:55:05:3c:10:8e:
90:02:21:00:d5:51:f6:d6:01:06:f1:ab:b4:84:cf:be:62:56:
c1:78:e4:ac:33:14:ea:19:19:1e:8b:60:7d:a5:ae:3b:da:16
The DER encoding of the above certificate is 316 bytes.
30 82 01 38 30 81 de a0 03 02 01 02 02 03 01 f5 0d 30 0a 06 08 2a 86
48 ce 3d 04 03 02 30 16 31 14 30 12 06 03 55 04 03 0c 0b 52 46 43 20
74 65 73 74 20 43 41 30 1e 17 0d 32 33 30 31 30 31 30 30 30 30 30 30
5a 17 0d 32 36 30 31 30 31 30 30 30 30 30 30 5a 30 22 31 20 30 1e 06
03 55 04 03 0c 17 30 31 2d 32 33 2d 34 35 2d 46 46 2d 46 45 2d 36 37
2d 38 39 2d 41 42 30 59 30 13 06 07 2a 86 48 ce 3d 02 01 06 08 2a 86
48 ce 3d 03 01 07 03 42 00 04 b1 21 6a b9 6e 5b 3b 33 40 f5 bd f0 2e
69 3f 16 21 3a 04 52 5e d4 44 50 b1 01 9c 2d fd 38 38 ab ac 4e 14 d8
6c 09 83 ed 5e 9e ef 24 48 c6 86 1c c4 06 54 71 77 e6 02 60 30 d0 51
f7 79 2a c2 06 a3 0f 30 0d 30 0b 06 03 55 1d 0f 04 04 03 02 07 80 30
0a 06 08 2a 86 48 ce 3d 04 03 02 03 49 00 30 46 02 21 00 d4 32 0b 1d
68 49 e3 09 21 9d 30 03 7e 13 81 66 f2 50 82 47 dd da e7 6c ce ea 55
05 3c 10 8e 90 02 21 00 d5 51 f6 d6 01 06 f1 ab b4 84 cf be 62 56 c1
78 e4 ac 33 14 ea 19 19 1e 8b 60 7d a5 ae 3b da 16
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A.1.1. Example: C509 Certificate Encoding
This section shows the C509 encoding of the X.509 certificate in the
previous section. The point compressed public key is represented as
described in Section 3.2.1.
Figure 21 shows the diagnostic notation of the unwrapped CBOR
sequence, ~C509Certificate, see Section 3.1.
/This defines a CBOR Sequence (RFC 8742):/
3, / version and certificate type /
h'01f50d', / serialNumber /
0, / signatureAlgorithm /
"RFC test CA", / issuer /
1672531200, / notBefore /
1767225600, / notAfter /
48(h'0123456789AB'), / subject, EUI-64 /
1, / subjectPublicKeyAlgorithm /
h'FEB1216AB96E5B3B3340F5BDF02E693F16213A04525ED44450
B1019C2DFD3838AB',
1, / single extension:
non-critical keyUsage
digitalSignature /
h'D4320B1D6849E309219D30037E138166F2508247DDDAE76CCE
EA55053C108E90D551F6D60106F1ABB484CFBE6256C178E4AC
3314EA19191E8B607DA5AE3BDA16'
Figure 21: CBOR diagnostic notation of ~C509Certificate
Figure 22 shows the plain hex format of the unwrapped CBOR sequence,
the size is 140 bytes.
03
43 01 F5 0D
00
6B 52 46 43 20 74 65 73 74 20 43 41
1A 63 B0 CD 00
1A 69 55 B9 00
D8 30 46 01 23 45 67 89 AB
01
58 21 FE B1 21 6A B9 6E 5B 3B 33 40 F5 BD F0 2E 69 3F 16 21 3A 04 52
5E D4 44 50 B1 01 9C 2D FD 38 38 AB
01
58 40 D4 32 0B 1D 68 49 E3 09 21 9D 30 03 7E 13 81 66 F2 50 82 47 DD
DA E7 6C CE EA 55 05 3C 10 8E 90 D5 51 F6 D6 01 06 F1 AB B4 84 CF BE
62 56 C1 78 E4 AC 33 14 EA 19 19 1E 8B 60 7D A5 AE 3B DA 16
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Figure 22: CBOR plain hex format of ~C509Certificate.
A.1.2. Example: Natively Signed C509 Certificate
This section shows the natively signed C509 certificate corresponding
to that of the previous section, which is identical except for
c509CertificateType, encoding of point compression (see
Section 3.2.1), and signatureValue.
Figure 23 shows the diagnostic notation of the natively signed
unwrapped CBOR sequence, ~C509Certificate.
/This defines a CBOR Sequence (RFC 8742):/
2,
h'01f50d',
0,
"RFC test CA",
1672531200,
1767225600,
48(h'0123456789AB'),
1,
h'02B1216AB96E5B3B3340F5BDF02E693F16213A04525ED44450
B1019C2DFD3838AB',
1,
h'EB0D472731F689BC00F5880B12C68B3F9FD38B23FADFCA2095
0F3F241B60A202579CAC28CD3B7494D5FA5D8BBAB4600357E5
50AB9FA9A65D9BA2B3B82E668CC6'
Figure 23: CBOR diagnostic notation of ~C509Certificate
Figure 24 shows the plain hex format of the natively signed unwrapped
CBOR sequence, the size is 140 bytes.
02
43 01 F5 0D
00
6B 52 46 43 20 74 65 73 74 20 43 41
1A 63 B0 CD 00
1A 69 55 B9 00
D8 30 46 01 23 45 67 89 AB
01
58 21 02 B1 21 6A B9 6E 5B 3B 33 40 F5 BD F0 2E 69 3F 16 21 3A 04 52
5E D4 44 50 B1 01 9C 2D FD 38 38 AB
01
58 40 EB 0D 47 27 31 F6 89 BC 00 F5 88 0B 12 C6 8B 3F 9F D3 8B 23 FA
DF CA 20 95 0F 3F 24 1B 60 A2 02 57 9C AC 28 CD 3B 74 94 D5 FA 5D 8B
BA B4 60 03 57 E5 50 AB 9F A9 A6 5D 9B A2 B3 B8 2E 66 8C C6
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Figure 24: CBOR plain hex format of ~C509Certificate.
A.1.3. C509 for Diffie-Hellman keys
The two previous examples illustrate keyUsage digitalSignature. A
C509 certificate for a public Diffie-Hellman key would instead have
key usage keyAgreement encoded according to Section 3.3 (in this case
of single extension encoded as integer 16 instead of 1 for digital
signature) but otherwise identical in format. Note that
Section 5.6.3.2 of [SP-800-56A] allows a key agreement key pair to be
used to sign a certification request.
A.1.4. Example: Additional Keys for the Example Certificates
Below are the issuer key pair and the subject private key belonging
to the above example certificates. The private keys are encoded as
in COSE [RFC9052]. These issuer key pair can be used to sign or
verify the example certificates and the subject private key allows
the example certificates to be used in test vectors for other
protocols like EDHOC.
issuerPublicKeyAlgorithm :
1 (EC Public Key (Weierstrass) with secp256r1)
issuerPublicKey :
h'02AE4CDB01F614DEFC7121285FDC7F5C6D1D42C95647F061BA0080DF678867845E'
issuerPrivateKey :
h'DC66B3415456D649429B53223DF7532B942D6B0E0842C30BCA4C0ACF91547BB2'
subjectPrivateKey :
h'D718111F3F9BD91B92FF6877F386BDBFCEA7154268FD7F2FB56EE17D99EA16D4'
A.1.5. Examples: C509Certificate and C509CertData
This section examplifies other CBOR objects defined in this
specification, based on the natively signed C509 certificate in
Appendix A.1.2.
Figure 25 shows the encoding of the corresponding C509Certificate,
i.e., the CBOR array wrapping of the CBOR sequence ~C509Certificate,
see Section 3.1.
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8B
02
43 01 F5 0D
00
6B 52 46 43 20 74 65 73 74 20 43 41
1A 63 B0 CD 00
1A 69 55 B9 00
D8 30 46 01 23 45 67 89 AB
01
58 21 02 B1 21 6A B9 6E 5B 3B 33 40 F5 BD F0 2E 69 3F 16 21 3A 04 52
5E D4 44 50 B1 01 9C 2D FD 38 38 AB
01
58 40 EB 0D 47 27 31 F6 89 BC 00 F5 88 0B 12 C6 8B 3F 9F D3 8B 23 FA
DF CA 20 95 0F 3F 24 1B 60 A2 02 57 9C AC 28 CD 3B 74 94 D5 FA 5D 8B
BA B4 60 03 57 E5 50 AB 9F A9 A6 5D 9B A2 B3 B8 2E 66 8C C6
Figure 25: C509Certificate: The CBOR array wrapping of
~C509Certificate
Note that C509Certificate is identical to ~C509Certificate in
Appendix A.1.2 except for the prefix 8B (which indicates that it is a
CBOR array with 11 elements).
Figure 26 shows the encoding of the corresponding C509CertData, i.e.,
the CBOR byte string wrapping of the CBOR sequence ~C509Certificate,
see Section 3.4.
58 8C
02
43 01 F5 0D
00
6B 52 46 43 20 74 65 73 74 20 43 41
1A 63 B0 CD 00
1A 69 55 B9 00
D8 30 46 01 23 45 67 89 AB
01
58 21 02 B1 21 6A B9 6E 5B 3B 33 40 F5 BD F0 2E 69 3F 16 21 3A 04 52
5E D4 44 50 B1 01 9C 2D FD 38 38 AB
01
58 40 EB 0D 47 27 31 F6 89 BC 00 F5 88 0B 12 C6 8B 3F 9F D3 8B 23 FA
DF CA 20 95 0F 3F 24 1B 60 A2 02 57 9C AC 28 CD 3B 74 94 D5 FA 5D 8B
BA B4 60 03 57 E5 50 AB 9F A9 A6 5D 9B A2 B3 B8 2E 66 8C C6
Figure 26: C509CertData: CBOR byte string wrapping of
~C509Certificate.
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Note that C509CertData is identical to ~C509Certificate in
Appendix A.1.2 except for the prefix 58 8C (which indicates that it
is a CBOR byte string of 140 bytes).
A.2. Example: IEEE 802.1AR profiled X.509 Certificate
An example of an IEEE 802.1AR profiled X.509 certificate (Secure
Device Identifier, DevID) is provided in Appendix C.2 of [RFC9148].
The certificate is shown below including details of the
hardwareModuleName type of otherName in subjectAltName, see
Section 3.3.
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Certificate:
Data:
Version: 3 (0x2)
Serial Number: 9112578475118446130 (0x7e7661d7b54e4632)
Signature Algorithm: ecdsa-with-SHA256
Issuer: C=US, ST=CA, O=Example Inc, OU=certification,
CN=802.1AR CA
Validity
Not Before: Jan 31 11:29:16 2019 GMT
Not After : Dec 31 23:59:59 9999 GMT
Subject: C=US, ST=CA, L=LA, O=example Inc,
OU=IoT/serialNumber=Wt1234
Subject Public Key Info:
Public Key Algorithm: id-ecPublicKey
Public-Key: (256 bit)
pub:
04:c8:b4:21:f1:1c:25:e4:7e:3a:c5:71:23:bf:2d:
9f:dc:49:4f:02:8b:c3:51:cc:80:c0:3f:15:0b:f5:
0c:ff:95:8d:75:41:9d:81:a6:a2:45:df:fa:e7:90:
be:95:cf:75:f6:02:f9:15:26:18:f8:16:a2:b2:3b:
56:38:e5:9f:d9
ASN1 OID: prime256v1
NIST CURVE: P-256
X509v3 extensions:
X509v3 Basic Constraints:
CA:FALSE
X509v3 Subject Key Identifier:
96:60:0D:87:16:BF:7F:D0:E7:52:D0:AC:76:07:77:AD:66:5D:02:A0
X509v3 Authority Key Identifier:
68:D1:65:51:F9:51:BF:C8:2A:43:1D:0D:9F:08:BC:2D:20:5B:11:60
X509v3 Key Usage: critical
Digital Signature, Key Encipherment
X509v3 Subject Alternative Name:
otherName:
type-id: 1.3.6.1.5.5.7.8.4 (id-on-hardwareModuleName)
value:
hwType: 1.3.6.1.4.1.6715.10.1
hwSerialNum: 01:02:03:04
Signature Algorithm: ecdsa-with-SHA256
Signature Value:
30:46:02:21:00:c0:d8:19:96:d2:50:7d:69:3f:3c:48:ea:a5:
ee:94:91:bd:a6:db:21:40:99:d9:81:17:c6:3b:36:13:74:cd:
86:02:21:00:a7:74:98:9f:4c:32:1a:5c:f2:5d:83:2a:4d:33:
6a:08:ad:67:df:20:f1:50:64:21:18:8a:0a:de:6d:34:92:36
The DER encoding of the certificate is 577 bytes:
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30 82 02 3D 30 82 01 E2 A0 03 02 01 02 02 08 7E 76 61 D7 B5 4E 46 32
30 0A 06 08 2A 86 48 CE 3D 04 03 02 30 5D 31 0B 30 09 06 03 55 04 06
13 02 55 53 31 0B 30 09 06 03 55 04 08 0C 02 43 41 31 14 30 12 06 03
55 04 0A 0C 0B 45 78 61 6D 70 6C 65 20 49 6E 63 31 16 30 14 06 03 55
04 0B 0C 0D 63 65 72 74 69 66 69 63 61 74 69 6F 6E 31 13 30 11 06 03
55 04 03 0C 0A 38 30 32 2E 31 41 52 20 43 41 30 20 17 0D 31 39 30 31
33 31 31 31 32 39 31 36 5A 18 0F 39 39 39 39 31 32 33 31 32 33 35 39
35 39 5A 30 5C 31 0B 30 09 06 03 55 04 06 13 02 55 53 31 0B 30 09 06
03 55 04 08 0C 02 43 41 31 0B 30 09 06 03 55 04 07 0C 02 4C 41 31 14
30 12 06 03 55 04 0A 0C 0B 65 78 61 6D 70 6C 65 20 49 6E 63 31 0C 30
0A 06 03 55 04 0B 0C 03 49 6F 54 31 0F 30 0D 06 03 55 04 05 13 06 57
74 31 32 33 34 30 59 30 13 06 07 2A 86 48 CE 3D 02 01 06 08 2A 86 48
CE 3D 03 01 07 03 42 00 04 C8 B4 21 F1 1C 25 E4 7E 3A C5 71 23 BF 2D
9F DC 49 4F 02 8B C3 51 CC 80 C0 3F 15 0B F5 0C FF 95 8D 75 41 9D 81
A6 A2 45 DF FA E7 90 BE 95 CF 75 F6 02 F9 15 26 18 F8 16 A2 B2 3B 56
38 E5 9F D9 A3 81 8A 30 81 87 30 09 06 03 55 1D 13 04 02 30 00 30 1D
06 03 55 1D 0E 04 16 04 14 96 60 0D 87 16 BF 7F D0 E7 52 D0 AC 76 07
77 AD 66 5D 02 A0 30 1F 06 03 55 1D 23 04 18 30 16 80 14 68 D1 65 51
F9 51 BF C8 2A 43 1D 0D 9F 08 BC 2D 20 5B 11 60 30 0E 06 03 55 1D 0F
01 01 FF 04 04 03 02 05 A0 30 2A 06 03 55 1D 11 04 23 30 21 A0 1F 06
08 2B 06 01 05 05 07 08 04 A0 13 30 11 06 09 2B 06 01 04 01 B4 3B 0A
01 04 04 01 02 03 04 30 0A 06 08 2A 86 48 CE 3D 04 03 02 03 49 00 30
46 02 21 00 C0 D8 19 96 D2 50 7D 69 3F 3C 48 EA A5 EE 94 91 BD A6 DB
21 40 99 D9 81 17 C6 3B 36 13 74 CD 86 02 21 00 A7 74 98 9F 4C 32 1A
5C F2 5D 83 2A 4D 33 6A 08 AD 67 DF 20 F1 50 64 21 18 8A 0A DE 6D 34
92 36
A.2.1. Example: C509 Certificate Encoding
The CBOR encoding (~C509Certificate) of the same X.509 certificate is
shown below in CBOR diagnostic format.
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/This defines a CBOR Sequence (RFC 8742):/
3,
h'7E7661D7B54E4632',
0,
[
-4, "US",
6, "CA",
8, "Example Inc",
9, "certification",
1, "802.1AR CA"
],
1548934156,
null,
[
-4, "US",
6, "CA",
5, "LA",
8, "example Inc",
9, "IoT",
-3, "Wt1234"
],
1,
h'FDC8B421F11C25E47E3AC57123BF2D9FDC494F028BC351CC80C03F150BF50CFF
95',
[
4, -2,
1, h'96600D8716BF7FD0E752D0AC760777AD665D02A0',
7, h'68D16551F951BFC82A431D0D9F08BC2D205B1160',
-2, 5,
3, [-1, [h'2B06010401B43B0A01', h'01020304']]
/ subjectAltName with hardwareModuleName /
],
h'C0D81996D2507D693F3C48EAA5EE9491BDA6DB214099D98117C63B361374CD86
A774989F4C321A5CF25D832A4D336A08AD67DF20F1506421188A0ADE6D349236'
The size of the CBOR encoding (CBOR sequence) is 275 bytes:
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03 48 7E 76 61 D7 B5 4E 46 32 00 8A 23 62 55 53 06 62 43 41 08 6B 45
78 61 6D 70 6C 65 20 49 6E 63 09 6D 63 65 72 74 69 66 69 63 61 74 69
6F 6E 01 6A 38 30 32 2E 31 41 52 20 43 41 1A 5C 52 DC 0C F6 8C 23 62
55 53 06 62 43 41 05 62 4C 41 08 6B 65 78 61 6D 70 6C 65 20 49 6E 63
09 63 49 6F 54 22 66 57 74 31 32 33 34 01 58 21 FD C8 B4 21 F1 1C 25
E4 7E 3A C5 71 23 BF 2D 9F DC 49 4F 02 8B C3 51 CC 80 C0 3F 15 0B F5
0C FF 95 8A 04 21 01 54 96 60 0D 87 16 BF 7F D0 E7 52 D0 AC 76 07 77
AD 66 5D 02 A0 07 54 68 D1 65 51 F9 51 BF C8 2A 43 1D 0D 9F 08 BC 2D
20 5B 11 60 21 05 03 82 20 82 49 2B 06 01 04 01 B4 3B 0A 01 44 01 02
03 04 58 40 C0 D8 19 96 D2 50 7D 69 3F 3C 48 EA A5 EE 94 91 BD A6 DB
21 40 99 D9 81 17 C6 3B 36 13 74 CD 86 A7 74 98 9F 4C 32 1A 5C F2 5D
83 2A 4D 33 6A 08 AD 67 DF 20 F1 50 64 21 18 8A 0A DE 6D 34 92 36
A.3. Example: CAB Baseline ECDSA HTTPS X.509 Certificate
The www.ietf.org HTTPS server replies with a certificate message with
2 certificates. The DER encoding of the first certificate is 1209
bytes.
30 82 04 b5 30 82 04 5a a0 03 02 01 02 02 10 04 7f a1 e3 19 28 ee 40
3b a0 b8 3a 39 56 73 fc 30 0a 06 08 2a 86 48 ce 3d 04 03 02 30 4a 31
0b 30 09 06 03 55 04 06 13 02 55 53 31 19 30 17 06 03 55 04 0a 13 10
43 6c 6f 75 64 66 6c 61 72 65 2c 20 49 6e 63 2e 31 20 30 1e 06 03 55
04 03 13 17 43 6c 6f 75 64 66 6c 61 72 65 20 49 6e 63 20 45 43 43 20
43 41 2d 33 30 1e 17 0d 32 30 30 37 32 39 30 30 30 30 30 30 5a 17 0d
32 31 30 37 32 39 31 32 30 30 30 30 5a 30 6d 31 0b 30 09 06 03 55 04
06 13 02 55 53 31 0b 30 09 06 03 55 04 08 13 02 43 41 31 16 30 14 06
03 55 04 07 13 0d 53 61 6e 20 46 72 61 6e 63 69 73 63 6f 31 19 30 17
06 03 55 04 0a 13 10 43 6c 6f 75 64 66 6c 61 72 65 2c 20 49 6e 63 2e
31 1e 30 1c 06 03 55 04 03 13 15 73 6e 69 2e 63 6c 6f 75 64 66 6c 61
72 65 73 73 6c 2e 63 6f 6d 30 59 30 13 06 07 2a 86 48 ce 3d 02 01 06
08 2a 86 48 ce 3d 03 01 07 03 42 00 04 96 3e cd d8 4d cd 1b 93 a1 cf
43 2d 1a 72 17 d6 c6 3b de 33 55 a0 2f 8c fb 5a d8 99 4c d4 4e 20 5f
15 f6 e3 d2 3b 38 2b a6 49 9b b1 7f 34 1f a5 92 fa 21 86 1f 16 d3 12
06 63 24 05 fd 70 42 bd a3 82 02 fd 30 82 02 f9 30 1f 06 03 55 1d 23
04 18 30 16 80 14 a5 ce 37 ea eb b0 75 0e 94 67 88 b4 45 fa d9 24 10
87 96 1f 30 1d 06 03 55 1d 0e 04 16 04 14 cc 0b 50 e7 d8 37 db f2 43
f3 85 3d 48 60 f5 3b 39 be 9b 2a 30 2e 06 03 55 1d 11 04 27 30 25 82
15 73 6e 69 2e 63 6c 6f 75 64 66 6c 61 72 65 73 73 6c 2e 63 6f 6d 82
0c 77 77 77 2e 69 65 74 66 2e 6f 72 67 30 0e 06 03 55 1d 0f 01 01 ff
04 04 03 02 07 80 30 1d 06 03 55 1d 25 04 16 30 14 06 08 2b 06 01 05
05 07 03 01 06 08 2b 06 01 05 05 07 03 02 30 7b 06 03 55 1d 1f 04 74
30 72 30 37 a0 35 a0 33 86 31 68 74 74 70 3a 2f 2f 63 72 6c 33 2e 64
69 67 69 63 65 72 74 2e 63 6f 6d 2f 43 6c 6f 75 64 66 6c 61 72 65 49
6e 63 45 43 43 43 41 2d 33 2e 63 72 6c 30 37 a0 35 a0 33 86 31 68 74
74 70 3a 2f 2f 63 72 6c 34 2e 64 69 67 69 63 65 72 74 2e 63 6f 6d 2f
43 6c 6f 75 64 66 6c 61 72 65 49 6e 63 45 43 43 43 41 2d 33 2e 63 72
6c 30 4c 06 03 55 1d 20 04 45 30 43 30 37 06 09 60 86 48 01 86 fd 6c
Preuß Mattsson, et al. Expires 24 October 2026 [Page 89]
Internet-Draft C509 Certificates April 2026
01 01 30 2a 30 28 06 08 2b 06 01 05 05 07 02 01 16 1c 68 74 74 70 73
3a 2f 2f 77 77 77 2e 64 69 67 69 63 65 72 74 2e 63 6f 6d 2f 43 50 53
30 08 06 06 67 81 0c 01 02 02 30 76 06 08 2b 06 01 05 05 07 01 01 04
6a 30 68 30 24 06 08 2b 06 01 05 05 07 30 01 86 18 68 74 74 70 3a 2f
2f 6f 63 73 70 2e 64 69 67 69 63 65 72 74 2e 63 6f 6d 30 40 06 08 2b
06 01 05 05 07 30 02 86 34 68 74 74 70 3a 2f 2f 63 61 63 65 72 74 73
2e 64 69 67 69 63 65 72 74 2e 63 6f 6d 2f 43 6c 6f 75 64 66 6c 61 72
65 49 6e 63 45 43 43 43 41 2d 33 2e 63 72 74 30 0c 06 03 55 1d 13 01
01 ff 04 02 30 00 30 82 01 05 06 0a 2b 06 01 04 01 d6 79 02 04 02 04
81 f6 04 81 f3 00 f1 00 76 00 f6 5c 94 2f d1 77 30 22 14 54 18 08 30
94 56 8e e3 4d 13 19 33 bf df 0c 2f 20 0b cc 4e f1 64 e3 00 00 01 73
9c 83 5f 8e 00 00 04 03 00 47 30 45 02 21 00 f8 d1 b4 a9 3d 2f 0d 4c
41 76 df b4 88 bc c7 3b 86 44 3d 7d e0 0e 6a c8 17 4d 89 48 a8 84 36
68 02 20 29 ff 5a 34 06 8a 24 0c 69 50 27 88 e8 ee 25 ab 7e d2 cb cf
68 6e ce 7b 5f 96 b4 31 a9 07 02 fa 00 77 00 5c dc 43 92 fe e6 ab 45
44 b1 5e 9a d4 56 e6 10 37 fb d5 fa 47 dc a1 73 94 b2 5e e6 f6 c7 0e
ca 00 00 01 73 9c 83 5f be 00 00 04 03 00 48 30 46 02 21 00 e8 91 c1
97 bf b0 e3 d3 0c b6 ce e6 0d 94 c3 c7 5f d1 17 53 36 93 11 08 d8 98
12 d4 d2 9d 81 d0 02 21 00 a1 59 d1 6c 46 47 d1 48 37 57 fc d6 ce 4e
75 ec 7b 5e f6 57 ef e0 28 f8 e5 cc 47 92 68 2d ac 43 30 0a 06 08 2a
86 48 ce 3d 04 03 02 03 49 00 30 46 02 21 00 bd 63 cf 4f 7e 5c fe 6c
29 38 5e a7 1c fb fc 1e 3f 7b 1c d0 72 51 a2 21 f7 77 69 c0 f4 71 df
ea 02 21 00 b5 c0 6c c4 58 54 fa 30 b2 82 88 b1 d3 bb 9a 66 61 ed 50
31 72 5b 1a 82 02 e0 da 5b 59 f9 54 02
A.3.1. Example: C509 Certificate Encoding
The CBOR encoding (~C509Certificate) of the first X.509 certificate
is shown below in CBOR diagnostic format.
/This defines a CBOR Sequence (RFC 8742):/
3,
h'047FA1E31928EE403BA0B83A395673FC',
0,
[
-4, "US",
-8, "Cloudflare, Inc.",
-1, "Cloudflare Inc ECC CA-3"
],
1595980800,
1627560000,
[
-4, "US",
-6, "CA",
-5, "San Francisco",
-8, "Cloudflare, Inc.",
-1, "sni.cloudflaressl.com"
Preuß Mattsson, et al. Expires 24 October 2026 [Page 90]
Internet-Draft C509 Certificates April 2026
],
1,
h'FD963ECDD84DCD1B93A1CF432D1A7217D6C63BDE3355A02F8CFB5AD8994CD44E
20',
[
7, h'A5CE37EAEBB0750E946788B445FAD9241087961F',
1, h'CC0B50E7D837DBF243F3853D4860F53B39BE9B2A',
3, [2, "sni.cloudflaressl.com", 2, "www.ietf.org"],
-2, 1,
8, [1, 2],
5, [
["http://crl3.digicert.com/CloudflareIncECCCA-3.crl",
null, null],
["http://crl4.digicert.com/CloudflareIncECCCA-3.crl",
null, null]
],
6, [h'6086480186FD6C0101', [1, "https://www.digicert.com/CPS"],
2, []],
9, [1, "http://ocsp.digicert.com",
2, "http://cacerts.digicert.com/CloudflareIncECCCA-3.crt"],
-4, -2,
h'2B06010401D679020402',
h'0481F300F1007600F65C942FD1773022145418083094568EE34D131933BFDF0C
2F200BCC4EF164E3000001739C835F8E0000040300473045022100F8D1B4A93D
2F0D4C4176DFB488BCC73B86443D7DE00E6AC8174D8948A8843668022029FF5A
34068A240C69502788E8EE25AB7ED2CBCF686ECE7B5F96B431A90702FA007700
5CDC4392FEE6AB4544B15E9AD456E61037FBD5FA47DCA17394B25EE6F6C70ECA
000001739C835FBE0000040300483046022100E891C197BFB0E3D30CB6CEE60D
94C3C75FD1175336931108D89812D4D29D81D0022100A159D16C4647D1483757
FCD6CE4E75EC7B5EF657EFE028F8E5CC4792682DAC43'
],
h'BD63CF4F7E5CFE6C29385EA71CFBFC1E3F7B1CD07251A221F77769C0F471DFEA
B5C06CC45854FA30B28288B1D3BB9A6661ED5031725B1A8202E0DA5B59F95402'
The size of the CBOR encoding (CBOR sequence) is 835 bytes.
A.4. Example: CAB Baseline RSA HTTPS X.509 Certificate
The tools.ietf.org HTTPS server replies with a certificate message
with 4 certificates. The DER encoding of the first certificate is
1647 bytes.
30 82 06 6b 30 82 05 53 a0 03 02 01 02 02 09 00 a6 a5 5c 87 0e 39 b4
0e 30 0d 06 09 2a 86 48 86 f7 0d 01 01 0b 05 00 30 81 c6 31 0b 30 09
06 03 55 04 06 13 02 55 53 31 10 30 0e 06 03 55 04 08 13 07 41 72 69
7a 6f 6e 61 31 13 30 11 06 03 55 04 07 13 0a 53 63 6f 74 74 73 64 61
6c 65 31 25 30 23 06 03 55 04 0a 13 1c 53 74 61 72 66 69 65 6c 64 20
54 65 63 68 6e 6f 6c 6f 67 69 65 73 2c 20 49 6e 63 2e 31 33 30 31 06
Preuß Mattsson, et al. Expires 24 October 2026 [Page 91]
Internet-Draft C509 Certificates April 2026
03 55 04 0b 13 2a 68 74 74 70 3a 2f 2f 63 65 72 74 73 2e 73 74 61 72
66 69 65 6c 64 74 65 63 68 2e 63 6f 6d 2f 72 65 70 6f 73 69 74 6f 72
79 2f 31 34 30 32 06 03 55 04 03 13 2b 53 74 61 72 66 69 65 6c 64 20
53 65 63 75 72 65 20 43 65 72 74 69 66 69 63 61 74 65 20 41 75 74 68
6f 72 69 74 79 20 2d 20 47 32 30 1e 17 0d 32 30 31 30 30 31 31 39 33
38 33 36 5a 17 0d 32 31 31 31 30 32 31 39 33 38 33 36 5a 30 3e 31 21
30 1f 06 03 55 04 0b 13 18 44 6f 6d 61 69 6e 20 43 6f 6e 74 72 6f 6c
20 56 61 6c 69 64 61 74 65 64 31 19 30 17 06 03 55 04 03 0c 10 2a 2e
74 6f 6f 6c 73 2e 69 65 74 66 2e 6f 72 67 30 82 01 22 30 0d 06 09 2a
86 48 86 f7 0d 01 01 01 05 00 03 82 01 0f 00 30 82 01 0a 02 82 01 01
00 b1 e1 37 e8 eb 82 d6 89 fa db f5 c2 4b 77 f0 2c 4a de 72 6e 3e 13
60 d1 a8 66 1e c4 ad 3d 32 60 e5 f0 99 b5 f4 7a 7a 48 55 21 ee 0e 39
12 f9 ce 0d ca f5 69 61 c7 04 ed 6e 0f 1d 3b 1e 50 88 79 3a 0e 31 41
16 f1 b1 02 64 68 a5 cd f5 4a 0a ca 99 96 35 08 c3 7e 27 5d d0 a9 cf
f3 e7 28 af 37 d8 b6 7b dd f3 7e ae 6e 97 7f f7 ca 69 4e cc d0 06 df
5d 27 9b 3b 12 e7 e6 fe 08 6b 52 7b 82 11 7c 72 b3 46 eb c1 e8 78 b8
0f cb e1 eb bd 06 44 58 dc 83 50 b2 a0 62 5b dc 81 b8 36 e3 9e 7c 79
b2 a9 53 8a e0 0b c9 4a 2a 13 39 31 13 bd 2c cf a8 70 cf 8c 8d 3d 01
a3 88 ae 12 00 36 1d 1e 24 2b dd 79 d8 53 01 26 ed 28 4f c9 86 94 83
4e c8 e1 14 2e 85 b3 af d4 6e dd 69 46 af 41 25 0e 7a ad 8b f2 92 ca
79 d9 7b 32 4f f7 77 e8 f9 b4 4f 23 5c d4 5c 03 ae d8 ab 3a ca 13 5f
5d 5d 5d a1 02 03 01 00 01 a3 82 02 e1 30 82 02 dd 30 0c 06 03 55 1d
13 01 01 ff 04 02 30 00 30 1d 06 03 55 1d 25 04 16 30 14 06 08 2b 06
01 05 05 07 03 01 06 08 2b 06 01 05 05 07 03 02 30 0e 06 03 55 1d 0f
01 01 ff 04 04 03 02 05 a0 30 3d 06 03 55 1d 1f 04 36 30 34 30 32 a0
30 a0 2e 86 2c 68 74 74 70 3a 2f 2f 63 72 6c 2e 73 74 61 72 66 69 65
6c 64 74 65 63 68 2e 63 6f 6d 2f 73 66 69 67 32 73 31 2d 32 34 32 2e
63 72 6c 30 63 06 03 55 1d 20 04 5c 30 5a 30 4e 06 0b 60 86 48 01 86
fd 6e 01 07 17 01 30 3f 30 3d 06 08 2b 06 01 05 05 07 02 01 16 31 68
74 74 70 3a 2f 2f 63 65 72 74 69 66 69 63 61 74 65 73 2e 73 74 61 72
66 69 65 6c 64 74 65 63 68 2e 63 6f 6d 2f 72 65 70 6f 73 69 74 6f 72
79 2f 30 08 06 06 67 81 0c 01 02 01 30 81 82 06 08 2b 06 01 05 05 07
01 01 04 76 30 74 30 2a 06 08 2b 06 01 05 05 07 30 01 86 1e 68 74 74
70 3a 2f 2f 6f 63 73 70 2e 73 74 61 72 66 69 65 6c 64 74 65 63 68 2e
63 6f 6d 2f 30 46 06 08 2b 06 01 05 05 07 30 02 86 3a 68 74 74 70 3a
2f 2f 63 65 72 74 69 66 69 63 61 74 65 73 2e 73 74 61 72 66 69 65 6c
64 74 65 63 68 2e 63 6f 6d 2f 72 65 70 6f 73 69 74 6f 72 79 2f 73 66
69 67 32 2e 63 72 74 30 1f 06 03 55 1d 23 04 18 30 16 80 14 25 45 81
68 50 26 38 3d 3b 2d 2c be cd 6a d9 b6 3d b3 66 63 30 2b 06 03 55 1d
11 04 24 30 22 82 10 2a 2e 74 6f 6f 6c 73 2e 69 65 74 66 2e 6f 72 67
82 0e 74 6f 6f 6c 73 2e 69 65 74 66 2e 6f 72 67 30 1d 06 03 55 1d 0e
04 16 04 14 ad 8a b4 1c 07 51 d7 92 89 07 b0 b7 84 62 2f 36 55 7a 5f
4d 30 82 01 06 06 0a 2b 06 01 04 01 d6 79 02 04 02 04 81 f7 04 81 f4
00 f2 00 77 00 f6 5c 94 2f d1 77 30 22 14 54 18 08 30 94 56 8e e3 4d
13 19 33 bf df 0c 2f 20 0b cc 4e f1 64 e3 00 00 01 74 e5 ac 71 13 00
00 04 03 00 48 30 46 02 21 00 8c f5 48 52 ce 56 35 43 39 11 cf 10 cd
b9 1f 52 b3 36 39 22 3a d1 38 a4 1d ec a6 fe de 1f e9 0f 02 21 00 bc
a2 25 43 66 c1 9a 26 91 c4 7a 00 b5 b6 53 ab bd 44 c2 f8 ba ae f4 d2
Preuß Mattsson, et al. Expires 24 October 2026 [Page 92]
Internet-Draft C509 Certificates April 2026
da f2 52 7c e6 45 49 95 00 77 00 5c dc 43 92 fe e6 ab 45 44 b1 5e 9a
d4 56 e6 10 37 fb d5 fa 47 dc a1 73 94 b2 5e e6 f6 c7 0e ca 00 00 01
74 e5 ac 72 3c 00 00 04 03 00 48 30 46 02 21 00 a5 e0 90 6e 63 e9 1d
4f dd ef ff 03 52 b9 1e 50 89 60 07 56 4b 44 8a 38 28 f5 96 dc 6b 28
72 6d 02 21 00 fc 91 ea ed 02 16 88 66 05 4e e1 8a 2e 53 46 c4 cc 51
fe b3 fa 10 a9 1d 2e db f9 91 25 f8 6c e6 30 0d 06 09 2a 86 48 86 f7
0d 01 01 0b 05 00 03 82 01 01 00 14 04 3f a0 be d2 ee 3f a8 6e 3a 1f
78 8e a0 4c 35 53 0f 11 06 1f ff 60 a1 6d 0b 83 e9 d9 2a db b3 3f 9d
b3 d7 e0 59 4c 19 a8 e4 19 a5 0c a7 70 72 77 63 d5 fe 64 51 0a d2 7a
d6 50 a5 8a 92 38 ec cb 2f 0f 5a c0 64 58 4d 5c 06 b9 73 63 68 27 8b
89 34 dc 79 c7 1d 3a fd 34 5f 83 14 41 58 49 80 68 29 80 39 8a 86 72
69 cc 79 37 ce e3 97 f7 dc f3 95 88 ed 81 03 29 00 d2 a2 c7 ba ab d6
3a 8e ca 09 0b d9 fb 39 26 4b ff 03 d8 8e 2d 3f 6b 21 ca 8a 7d d8 5f
fb 94 ba 83 de 9c fc 15 8d 61 fa 67 2d b0 c7 db 3d 25 0a 41 4a 85 d3
7f 49 46 37 3c f4 b1 75 d0 52 f3 dd c7 66 f1 4b fd aa 00 ed bf e4 7e
ed 01 ec 7b e4 f6 46 fc 31 fd 72 fe 03 d2 f2 65 af 4d 7e e2 81 9b 7a
fd 30 3c f5 52 f4 05 34 a0 8a 3e 19 41 58 c8 a8 e0 51 71 84 09 15 ae
ec a5 77 75 fa 18 f7 d5 77 d5 31 cc c7 2d
A.4.1. Example: C509 Certificate Encoding
The CBOR encoding (~C509Certificate) of the first X.509 certificate
is shown below in CBOR diagnostic format.
/This defines a CBOR Sequence (RFC 8742):/
3,
h'A6A55C870E39B40E',
23,
[
-4, "US",
-6, "Arizona",
-5, "Scottsdale",
-8, "Starfield Technologies, Inc.",
-9, "http://certs.starfieldtech.com/repository/",
-1, "Starfield Secure Certificate Authority - G2"
],
1601581116,
1635881916,
[
-9, "Domain Control Validated",
1, "*.tools.ietf.org"
],
0,
h'B1E137E8EB82D689FADBF5C24B77F02C4ADE726E3E1360D1A8661EC4AD3D3260
E5F099B5F47A7A485521EE0E3912F9CE0DCAF56961C704ED6E0F1D3B1E508879
3A0E314116F1B1026468A5CDF54A0ACA99963508C37E275DD0A9CFF3E728AF37
D8B67BDDF37EAE6E977FF7CA694ECCD006DF5D279B3B12E7E6FE086B527B8211
Preuß Mattsson, et al. Expires 24 October 2026 [Page 93]
Internet-Draft C509 Certificates April 2026
7C72B346EBC1E878B80FCBE1EBBD064458DC8350B2A0625BDC81B836E39E7C79
B2A9538AE00BC94A2A13393113BD2CCFA870CF8C8D3D01A388AE1200361D1E24
2BDD79D8530126ED284FC98694834EC8E1142E85B3AFD46EDD6946AF41250E7A
AD8BF292CA79D97B324FF777E8F9B44F235CD45C03AED8AB3ACA135F5D5D5DA1',
[
-4, -2,
8, [ 1, 2 ],
-2, 5,
5, "http://crl.starfieldtech.com/sfig2s1-242.crl",
6, [ h'6086480186FD6E01071701',
[1, "http://certificates.starfieldtech.com/repository/"],
1,
[]
],
9, [ 1, "http://ocsp.starfieldtech.com/", 2,
"http://certificates.starfieldtech.com/repository/sfig2.crt"],
7, h'254581685026383D3B2D2CBECD6AD9B63DB36663',
3, [ 2, "*.tools.ietf.org", 2, "tools.ietf.org" ],
1, h'AD8AB41C0751D7928907B0B784622F36557A5F4D',
h'2B06010401D679020402',
h'0481F400F2007700F65C942FD1773022145418083094568EE34D131933BFDF0C
2F200BCC4EF164E300000174E5AC711300000403004830460221008CF54852CE
5635433911CF10CDB91F52B33639223AD138A41DECA6FEDE1FE90F022100BCA2
254366C19A2691C47A00B5B653ABBD44C2F8BAAEF4D2DAF2527CE64549950077
005CDC4392FEE6AB4544B15E9AD456E61037FBD5FA47DCA17394B25EE6F6C70E
CA00000174E5AC723C0000040300483046022100A5E0906E63E91D4FDDEFFF03
52B91E50896007564B448A3828F596DC6B28726D022100FC91EAED0216886605
4EE18A2E5346C4CC51FEB3FA10A91D2EDBF99125F86CE6'
],
h'14043FA0BED2EE3FA86E3A1F788EA04C35530F11061FFF60A16D0B83E9D92ADB
B33F9DB3D7E0594C19A8E419A50CA770727763D5FE64510AD27AD650A58A9238
ECCB2F0F5AC064584D5C06B9736368278B8934DC79C71D3AFD345F8314415849
80682980398A867269CC7937CEE397F7DCF39588ED81032900D2A2C7BAABD63A
8ECA090BD9FB39264BFF03D88E2D3F6B21CA8A7DD85FFB94BA83DE9CFC158D61
FA672DB0C7DB3D250A414A85D37F4946373CF4B175D052F3DDC766F14BFDAA00
EDBFE47EED01EC7BE4F646FC31FD72FE03D2F265AF4D7EE2819B7AFD303CF552
F40534A08A3E194158C8A8E05171840915AEECA57775FA18F7D577D531CCC72D'
The size of the CBOR encoding (CBOR sequence) is 1295 bytes.
A.5. Example: Certificate with Extensions IPAddrBlocks and
IPAddrBlocksV2
An example X.509 certificate with extensions IPAddrBlocks and
IPAddrBlocksV2.
Preuß Mattsson, et al. Expires 24 October 2026 [Page 94]
Internet-Draft C509 Certificates April 2026
Certificate:
SHA256 Fingerprint:
c4917e6e4be1fe23eea1862fb57061aecead12b30db8f536cfe0da4a899bec75
Data:
Version: v3 (2)
Serial Number:
12:34
Issuer: CN=selfsign-brainpoolp384r1,SURNAME=my surname,
T=my title, GIVENNAME=my givenName,Name=my name
Validity:
Not Before: Thu Jan 02 01:00:00 CET 2025
Not After : Fri Jan 02 01:00:00 CET 2026
Subject: CN=selfsign-brainpoolp384r1,SURNAME=my surname,
T=my title ,GIVENNAME=my givenName,Name=my name
Subject Public Key Info:
Public Key Algorithm: EC/BRAINPOOLP384R1
Pub:
04:67:09:c9:92:91:9b:49:c4:8f:d9:31:d0:5c:49:7d:38:65:
e6:08:4c:91:df:3a:4c:7e:78:1f:41:85:43:b0:23:d5:9e:8b:
f2:5d:13:3f:b1:a0:94:e9:d4:2c:8f:a6:ed:3b:46:e9:88:3a:
35:ab:d4:b0:a9:d3:0a:ae:fd:9b:7e:88:ed:38:00:56:5d:1e:
7f:06:33:13:4d:65:19:29:2d:49:bd:55:ec:30:a1:67:19:7f:
ec:0f:74:29:82:2b:95
X509v3 extensions:
X509v3 keyUsage:
digitalSignature
X509v3 sbgp-ipAddrBlock:
IPv4:
22.82.0.0/16
23.83.112.0/20
23.106.104.0 - 23.106.119.255
23.109.0.0/16
23.111.16.0 - 23.111.63.255
IPv6:
2001:5::/32
2001:600:: - 2001:7f9:ffff:ffff:ffff:ffff:ffff:ffff
2001:7fb:: - 2001:bff:ffff:ffff:ffff:ffff:ffff:ffff
2001:1400::/22
X509v3 sbgp-ipAddrBlockV2:
IPv4 unicast:
22.82.0.0/16
23.83.112.0/20
23.106.104.0 - 23.106.119.255
23.109.0.0/16
23.111.16.0 - 23.111.63.255
IPv6 unicast:
2001:5::/32
2002:2::/72
Preuß Mattsson, et al. Expires 24 October 2026 [Page 95]
Internet-Draft C509 Certificates April 2026
2002:3:: - 2002:8:0:ffff:ffff:ffff:ffff:ffff
Signature Algorithm: SHA384WITHECDSA
Signature Value:
30:64:02:30:67:09:c9:92:91:9b:49:c4:8f:d9:31:d0:5c:49:
7d:38:65:e6:08:4c:91:df:3a:4c:7e:78:1f:41:85:43:b0:23:
d5:9e:8b:f2:5d:13:3f:b1:a0:94:e9:d4:2c:8f:a6:ed:02:30:
3f:7d:d0:c9:cf:50:86:29:85:29:f0:22:b8:2b:f6:32:f4:9d:
40:9a:2f:2e:70:0e:c2:b0:bd:24:a3:bb:09:41:85:da:7c:21:
af:47:9f:10:81:9a:41:04:c1:a4:b3:76
The DER encoding of the certificate is 791 bytes:
30 82 03 13 30 82 02 9a a0 03 02 01 02 02 02 12 34 30 0a 06 08 2a 86
48 ce 3d 04 03 03 30 74 31 21 30 1f 06 03 55 04 03 0c 18 73 65 6c 66
73 69 67 6e 2d 62 72 61 69 6e 70 6f 6f 6c 70 33 38 34 72 31 31 13 30
11 06 03 55 04 04 0c 0a 6d 79 20 73 75 72 6e 61 6d 65 31 11 30 0f 06
03 55 04 0c 0c 08 6d 79 20 74 69 74 6c 65 31 15 30 13 06 03 55 04 2a
0c 0c 6d 79 20 67 69 76 65 6e 4e 61 6d 65 31 10 30 0e 06 03 55 04 29
0c 07 6d 79 20 6e 61 6d 65 30 1e 17 0d 32 35 30 31 30 32 30 30 30 30
30 30 5a 17 0d 32 36 30 31 30 32 30 30 30 30 30 30 5a 30 74 31 21 30
1f 06 03 55 04 03 0c 18 73 65 6c 66 73 69 67 6e 2d 62 72 61 69 6e 70
6f 6f 6c 70 33 38 34 72 31 31 13 30 11 06 03 55 04 04 0c 0a 6d 79 20
73 75 72 6e 61 6d 65 31 11 30 0f 06 03 55 04 0c 0c 08 6d 79 20 74 69
74 6c 65 31 15 30 13 06 03 55 04 2a 0c 0c 6d 79 20 67 69 76 65 6e 4e
61 6d 65 31 10 30 0e 06 03 55 04 29 0c 07 6d 79 20 6e 61 6d 65 30 7a
30 14 06 07 2a 86 48 ce 3d 02 01 06 09 2b 24 03 03 02 08 01 01 0b 03
62 00 04 67 09 c9 92 91 9b 49 c4 8f d9 31 d0 5c 49 7d 38 65 e6 08 4c
91 df 3a 4c 7e 78 1f 41 85 43 b0 23 d5 9e 8b f2 5d 13 3f b1 a0 94 e9
d4 2c 8f a6 ed 3b 46 e9 88 3a 35 ab d4 b0 a9 d3 0a ae fd 9b 7e 88 ed
38 00 56 5d 1e 7f 06 33 13 4d 65 19 29 2d 49 bd 55 ec 30 a1 67 19 7f
ec 0f 74 29 82 2b 95 a3 81 fa 30 81 f7 30 0b 06 03 55 1d 0f 04 04 03
02 07 80 30 75 06 08 2b 06 01 05 05 07 01 07 04 69 30 67 30 32 04 02
00 01 30 2c 03 03 00 16 52 03 04 04 17 53 70 30 0c 03 04 00 17 6a 68
03 04 00 17 6a 77 03 03 00 17 6d 30 0c 03 04 00 17 6f 10 03 04 00 17
6f 3f 30 31 04 02 00 02 30 2b 03 05 00 20 01 00 05 30 0d 03 04 00 20
01 06 03 05 00 20 01 07 f9 30 0d 03 05 00 20 01 07 fb 03 04 00 20 01
0b 03 04 02 20 01 14 30 71 06 08 2b 06 01 05 05 07 01 1c 04 65 30 63
30 33 04 03 00 01 01 30 2c 03 03 00 16 52 03 04 04 17 53 70 30 0c 03
04 00 17 6a 68 03 04 00 17 6a 77 03 03 00 17 6d 30 0c 03 04 00 17 6f
10 03 04 00 17 6f 3f 30 2c 04 03 00 02 01 30 25 03 05 00 20 01 00 05
03 0a 00 20 02 00 02 00 00 00 00 00 30 10 03 05 00 20 02 00 03 03 07
00 20 02 00 08 00 00 30 0a 06 08 2a 86 48 ce 3d 04 03 03 03 67 00 30
64 02 30 67 09 c9 92 91 9b 49 c4 8f d9 31 d0 5c 49 7d 38 65 e6 08 4c
91 df 3a 4c 7e 78 1f 41 85 43 b0 23 d5 9e 8b f2 5d 13 3f b1 a0 94 e9
d4 2c 8f a6 ed 02 30 3f 7d d0 c9 cf 50 86 29 85 29 f0 22 b8 2b f6 32
f4 9d 40 9a 2f 2e 70 0e c2 b0 bd 24 a3 bb 09 41 85 da 7c 21 af 47 9f
10 81 9a 41 04 c1 a4 b3 76
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A.5.1. Example: C509 Certificate Encoding
The CBOR encoding (~C509Certificate) of the X.509 certificate is
shown below in CBOR diagnostic format.
/This defines a CBOR Sequence (RFC 8742):/
3,
h'1234',
1,
null,
1735776000,
1767312000,
[
1, "selfsign-brainpoolp384r1", 2, "my surname", 10, "my title",
13, "my givenName", 25, "my name"
],
25,
h'046709C992919B49C48FD931D05C497D3865E6084C91DF3A4C7E781F418543B0
23D59E8BF25D133FB1A094E9D42C8FA6ED3B46E9883A35ABD4B0A9D30AAEFD9B
7E88ED3800565D1E7F0633134D6519292D49BD55EC30A167197FEC0F7429822B
95',
[
2, 1,
32, [ 1, null,
[
71250, 85343518, [-67102984, 15], -18240266,
[18241443, 47]
],
2, null,
[
4831903749, [-4813029119, 4813031155], [2, -4813031152],
33554441]
],
34, [ 1, 1,
[
71250, 85343518, [-67102984, 15], -18240266, [18241443, 47]
],
2, 1,
[
h'0020010005', h'00200200020000000000',
[h'0020020003', h'00200200080000']
]
]
],
h'6709C992919B49C48FD931D05C497D3865E6084C91DF3A4C7E781F418543B023
D59E8BF25D133FB1A094E9D42C8FA6ED3F7DD0C9CF5086298529F022B82BF632
F49D409A2F2E700EC2B0BD24A3BB094185DA7C21AF479F10819A4104C1A4B376'
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Acknowledgments
The authors want to thank Henk Birkholz, Mohamed Boucadair, Corey
Bonnell, Carsten Bormann, Viktor Dukhovni, Russ Housley, Paul
Hoffmann, Christopher Inacio, Olle Johansson, Benjamin Kaduk, Ted
Lemon, Ilari Liusvaara, Laurence Lundblade, Francesca Palombini,
Thomas Peterson, Michael Richardson, Stefan Santesson, Jim Schaad,
Brian Sipos, Rene Struik, Fraser Tweedale, Gunter Van de Velde, Éric
Vyncke, and Paul Wouters for reviewing and commenting on intermediate
versions of the draft.
Authors' Addresses
John Preuß Mattsson
Ericsson AB
Email: john.mattsson@ericsson.com
Göran Selander
Ericsson AB
Email: goran.selander@ericsson.com
Shahid Raza
University of Glasgow
Email: shahid.raza@glasgow.ac.uk
Joel Höglund
RISE AB
Email: joel.hoglund@ri.se
Martin Furuhed
IN Groupe
Email: martin.furuhed@ingroupe.com
Lijun Liao
NIO
Email: lijun.liao@nio.io
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