CBOR Encoded X.509 Certificates (C509 Certificates)
draft-ietf-cose-cbor-encoded-cert-13
The information below is for an old version of the document.
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| Authors | John Preuß Mattsson , Göran Selander , Shahid Raza , Joel Höglund , Martin Furuhed | ||
| Last updated | 2025-03-03 (Latest revision 2025-01-08) | ||
| Replaces | draft-mattsson-cose-cbor-cert-compress | ||
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draft-ietf-cose-cbor-encoded-cert-13
Network Working Group J. Preuß Mattsson
Internet-Draft G. Selander
Updates: 6698 (if approved) Ericsson AB
Intended status: Standards Track S. Raza
Expires: 4 September 2025 J. Höglund
RISE AB
M. Furuhed
Nexus Group
3 March 2025
CBOR Encoded X.509 Certificates (C509 Certificates)
draft-ietf-cose-cbor-encoded-cert-13
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 and all certificates
compatible with the RFC 7925, IEEE 802.1AR (DevID), CNSA, RPKI, GSMA
eUICC, and CA/Browser Forum Baseline Requirements profiles. When
used to re-encode DER encoded X.509 certificates, the CBOR encoding
can in many cases reduce the size of RFC 7925 profiled certificates
with over 50% while also significantly reducing memory and code size
compared to ASN.1. The CBOR encoded structure can alternatively be
signed directly ("natively signed"), which does not require re-
encoding for the signature to be verified. The TLSA selectors
registry defined in RFC 6698 is extended to include CBOR
certificates. The document also specifies C509 Certificate Signing
Requests, C509 COSE headers, a C509 TLS certificate type, and a C509
file format.
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/.
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.
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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 4 September 2025.
Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
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Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Notational Conventions . . . . . . . . . . . . . . . . . . . 5
3. C509 Certificate . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Message Fields . . . . . . . . . . . . . . . . . . . . . 6
3.2. Encoding of subjectPublicKey and issuerSignatureValue . . 10
3.3. Encoding of Extensions . . . . . . . . . . . . . . . . . 11
3.4. COSE Header Parameters . . . . . . . . . . . . . . . . . 17
3.5. Private Key Structures . . . . . . . . . . . . . . . . . 18
3.6. Deterministic Encoding . . . . . . . . . . . . . . . . . 18
4. C509 Certificate Signing Request . . . . . . . . . . . . . . 19
5. C509 Processing and Certificate Issuance . . . . . . . . . . 21
6. Legacy Considerations . . . . . . . . . . . . . . . . . . . . 22
7. Expected Certificate Sizes . . . . . . . . . . . . . . . . . 23
8. Security Considerations . . . . . . . . . . . . . . . . . . . 24
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24
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9.1. C509 Certificate Types Registry . . . . . . . . . . . . . 25
9.2. C509 Certificate Request Types Registry . . . . . . . . . 25
9.3. C509 Attributes Registry . . . . . . . . . . . . . . . . 26
9.4. C509 Extensions Registry . . . . . . . . . . . . . . . . 30
9.5. C509 Certificate Policies Registry . . . . . . . . . . . 35
9.6. C509 Policies Qualifiers Registry . . . . . . . . . . . . 37
9.7. C509 Information Access Registry . . . . . . . . . . . . 38
9.8. C509 Extended Key Usages Registry . . . . . . . . . . . . 40
9.9. C509 General Names Registry . . . . . . . . . . . . . . . 42
9.10. C509 Signature Algorithms Registry . . . . . . . . . . . 44
9.11. C509 Public Key Algorithms Registry . . . . . . . . . . . 48
9.12. COSE Header Parameters Registry . . . . . . . . . . . . . 51
9.13. Media Type application/cose-c509-cert . . . . . . . . . . 51
9.14. Media Type application/cose-c509-pkcs10 . . . . . . . . . 53
9.15. Media Type application/cose-c509-privkey . . . . . . . . 54
9.16. Media Type application/cose-c509-pem . . . . . . . . . . 55
9.17. CoAP Content-Formats Registry . . . . . . . . . . . . . . 56
9.18. TLS Certificate Types Registry . . . . . . . . . . . . . 56
9.19. CBOR Tags Registry . . . . . . . . . . . . . . . . . . . 57
9.20. TLSA Selectors Registry . . . . . . . . . . . . . . . . . 57
9.21. EDHOC Authentication Credential Types Registry . . . . . 57
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 57
10.1. Normative References . . . . . . . . . . . . . . . . . . 57
10.2. Informative References . . . . . . . . . . . . . . . . . 60
Appendix A. Example C509 Certificates . . . . . . . . . . . . . 62
A.1. Example RFC 7925 profiled X.509 Certificate . . . . . . . 63
A.2. Example IEEE 802.1AR profiled X.509 Certificate . . . . . 67
A.3. Example CAB Baseline ECDSA HTTPS X.509 Certificate . . . 71
A.4. Example CAB Baseline RSA HTTPS X.509 Certificate . . . . 73
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 76
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 77
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 RPKI [RFC6487] where a single certificate can be very
large. More compact certificate representations are therefore
desirable in many use cases. Due to the current PKI usage of DER
encoded X.509 certificates, keeping compatibility with DER encoded
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X.509 is necessary at least for a transition period. However, the
use of a more compact encoding with the Concise Binary Object
Representation (CBOR) [RFC8949] reduces the certificate size
significantly which has known performance benefits in terms of
decreased communication overhead, power consumption, latency,
storage, etc. The use of CBOR also reduces code complexity, code
size, memory usage, and CPU usage.
CBOR is a data format designed for small code size and small message
size. 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. The Concise Data Definition
Language (CDDL) [RFC8610] provides a way to express structures for
protocol messages and APIs that use CBOR. RFC 8610 also extends the
diagnostic notation.
CBOR data items are encoded to or decoded from byte strings using a
type-length-value encoding scheme, where the three highest order bits
of the initial byte contain information about the major type. CBOR
supports several different types of data items, in addition to
integers (int, uint), simple values (e.g. null), byte strings (bstr),
and text strings (tstr), CBOR also supports arrays [] of data items,
maps {} of pairs of data items, and sequences of data items. For a
complete specification and examples, see [RFC8949], [RFC8610], and
[RFC8742]. We recommend implementors to get used to CBOR by using
the CBOR playground [CborMe].
CAB Baseline Requirements [CAB-TLS], RFC 7925 [RFC7925], IEEE 802.1AR
[IEEE-802.1AR], and CNSA [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]. RFC 7925
[RFC7925], RFC7925bis [I-D.ietf-uta-tls13-iot-profile], and IEEE
802.1AR [IEEE-802.1AR] specifically target Internet of Things
deployments. This document specifies a CBOR encoding based on
[X.509-IoT], which can support large parts of RFC 5280. The encoding
supports all RFC 7925, IEEE 802.1AR, CAB Baseline [CAB-TLS],
[CAB-Code], RPKI [RFC6487], eUICC [GSMA-eUICC] profiled X.509
certificates, and is designed to render a compact encoding of
certificates used in constrained environments.
The resulting certificates are called C509 Certificates. This
document does not specify a certificate profile. Two variants are
defined using the same CBOR encoding and differing only in what is
being signed:
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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.
2. Natively signed C509 certificates, where the signature is
calculated over the CBOR encoding instead of over the DER
encoding as in 1. 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 Certificate Signing Requests, see
Section 4; COSE headers for use of the C509 certificates with COSE,
see Section 9.12; and a TLS certificate type for use of the C509
certificates with TLS and QUIC (with or without additional TLS
certificate compression), see Section 9.18.
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.
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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 order of elements in arrays are
always encoded in the same order as the elements or the corresponding
SEQUENCE or SET in the DER encoding.
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.
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).
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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: any,
extensions: Extensions,
)
CertificateSerialNumber = ~biguint
Name = [ * Attribute ] / text / bytes
Attribute = (( attributeType: int, attributeValue: text ) //
( attributeType: ~oid, attributeValue: bytes ))
AlgorithmIdentifier = int / ~oid /
[ algorithm: ~oid, parameters: bytes ]
Extensions = [ * Extension ] / int
Extension = (( extensionID: int, extensionValue: any ) //
( extensionID: ~oid, ? critical: true,
extensionValue: bytes ))
Figure 1: CDDL for C509Certificate.
C509 certificates are defined in terms of DER encoded [RFC5280] X.509
certificates as detailed in the following subsections.
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. Currently, the type can be a natively signed C509
certificate following X.509 v3 (c509CertificateType = 2) or a CBOR
re-encoded X.509 v3 DER certificate (c509CertificateType = 3), see
Section 9.1.
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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 9.10) 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 'Attribute' is encoded as a CBOR
array of Attributes. RelativeDistinguishedName with more than one
AttributeTypeAndValue is not supported. Each Attribute is encoded as
either
* a (CBOR int, CBOR text string) pair, or
* a (unwrapped CBOR OID, CBOR bytes) pair.
The absolute value of the CBOR int (see Figure 8) encodes the
attribute type and the sign is used to represent the character string
type; positive for utf8String, negative for printableString. The
attribute value for emailAddress and domainComponent are always of
type IA5String (see [RFC5280]).In natively signed C509 certificates
all text strings are UTF-8 encoded and all attributeType SHALL be
non-negative. Text strings SHALL still adhere to any X.509
restrictions, i.e., serialNumber SHALL only contain the 74 character
subset of ASCII allowed by printableString and countryName SHALL have
length 2. In re-encoded C509 certificates, attribute values of types
ia5String (if this is the only allowed type, e.g. emailAddress),
printableString and utf8String are allowed, and the string types
teletexString, universalString, and bmpString are not supported.
If Name contains a single Attribute containing an utf8String encoded
'common name' it is encoded 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,
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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.
If the 'issuer' field is identical to the 'subject' field, e.g. in
case of self-signed certificates, then it MUST be encoded as CBOR
null.
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 CBOR null.
3.1.6. subject
The 'subject' field is encoded exactly like issuer, except that CBOR
null is not a valid value.
3.1.7. subjectPublicKeyInfo
The 'AlgorithmIdentifier' field including parameters is encoded as
the CBOR int 'subjectPublicKeyAlgorithm' (see Section 9.11) 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. 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.
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3.1.10. extensions
The 'extensions' field is encoded as a CBOR array where each
extension is encoded as either:
* a CBOR int (see Section 9.4) followed by a CBOR item of any type,
or
* an unwrapped CBOR OID tag [RFC9090] followed by an optional CBOR
bool encoding 'critical' and the DER encoded value of the
'extnValue' encoded as a CBOR byte string.
If the array contains exactly two ints and the absolute value of the
first int is 2 (corresponding to keyUsage), the 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. Extensions
are encoded as specified in Section 3.3. The extensions mandated to
be supported by [RFC7925] and [IEEE-802.1AR] are given special
treatment. An omitted 'extensions' field is encoded as an empty CBOR
array.
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 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 is
omitted and subjectPublicKey consist of only the modulus encoded as
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an unwrapped CBOR unsigned bignum (~biguint).
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, the octets 0xfe and 0xfd are
used instead of 0x02 and 0x03 in the CBOR encoding to represent even
and odd y-coordinate, respectively.
3.2.2. Encoding of issuerSignatureValue
For ECDSA signatures, the SEQUENCE and INTEGER type and length fields
as well as the any leading 0x00 byte (to indicate that the number is
not negative) are omitted. If the two INTEGER value fields have
different lengths, the shorter INTEGER value field is padded with
zeroes so that the two fields have the same length. 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.
The 'extensions' field is encoded as a CBOR array where each
extensionID is encoded either as a CBOR int (see Section 9.4) or as
an unwrapped CBOR OID tag [RFC9090]. If 'extensionID' is encoded an
int, the sign is used to encode that the extension is critical.
Critical extensions are encoded with a negative sign and non-critical
extensions are encoded with a positive sign. If 'extensionID' is
encoded as an unwrapped CBOR OID tag, then an optional boolean
element in the array is used to indicate that the extension is
critical, see Figure 1.
The 'extnValue' OCTET STRING value field is encoded as the CBOR byte
string 'extensionValue' except for the extensions specified below.
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.
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CBOR encoding of the following extension values is fully supported:
* Subject Key Identifier (subjectKeyIdentifier). In natively signed
certificates, KeyIdentifier SHOULD 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
* 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 = int
* Policy Mappings (policyMappings). extensionValue is encoded as
follows:
PolicyMappings = [
+ (issuerDomainPolicy: ~oid, subjectDomainPolicy: ~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 9.8), 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
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* 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 9.9 the extension value can be CBOR encoded.
extensionValue is encoded as an array of (int, any) pairs where
each pair encodes a general name (see Section 9.9). 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 hardwareModuleName type of otherName has been given
its own int due to its mandatory use in IEEE 802.1AR. When
'otherName + hardwareModuleName' is used, then [ ~oid, bytes ] is
used to contain the pair ( hwType, hwSerialNum ) directly as
specified in [RFC4108]. Only the general names in Section 9.9 are
supported.
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 the CRL
Distribution Points is a sequence of DistributionPointName, where
each DistributionPointName only contains
uniformResourceIdentifiers, the extension value can be CBOR
encoded. extensionValue is encoded as follows:
DistributionPointName = [ 2* text ] / text
CRLDistributionPoints = [ + DistributionPointName ]
* 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
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encoded. Each accessMethod is encoded as a CBOR int (see
Section 9.7) 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 certSerialNumberm 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 9.5 are
encoded as an int. The policyQualifierId is encoded as an CBOR
int (see Section 9.6) or an unwrapped CBOR OID tag [RFC9090].
PolicyIdentifier = int / ~oid
PolicyQualifierInfo = (
policyQualifierId: int / ~oid,
qualifier: text,
)
CertificatePolicies = [
+ ( PolicyIdentifier, ? [ + PolicyQualifierInfo ] )
]
* Name Constraints (nameConstraints). If the name constraints only
contain general names registered in Section 9.9 the extension
value can be CBOR encoded. C509 uses the same additions and
restrictions as defined in Section 4.2.1.10 of [RFC5280]. Note
that the minimum and maximum fields are not used and therefore
omitted.
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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.
Attributes = (( attributeType: int, attributeValue: [+text] ) //
( attributeType: ~oid, attributeValue: [+bytes] ))
SubjectDirectoryAttributes = [+Attributes]
* AS Resources (id-pe-autonomousSysIds). If rdi is not present, the
extension value can be CBOR encoded. Each ASId is encoded as an
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 Resources v2 (id-pe-autonomousSysIds-v2). Encoded exactly like
autonomousSysIds.
* IP Resources (id-pe-ipAddrBlocks). If rdi and SAFI is not
present, the extension value can be CBOR encoded. Each
AddressPrefix is encoded as a CBOR bytes string (without the
unused bits octet) followed by the number of unused bits encoded
as a CBOR uint. Each AddressRange is encoded as an array of two
CBOR byte strings. The unused bits for min and max are omitted,
but the unused bits in max IPAddress is set to ones. With the
exception of the first Address, if the byte string has the same
length as the previous Address, the Address is encoded as an uint
with the the difference to the previous Address. It should be
noted that using address differences for compactness prevents
encoding an address range larger than 2^64 - 1 corresponding to
the CBOR integer max value.
Address = bytes
AddressPrefix = (Address, unusedBits: uint)
AddressRange = [min: Address, max: Address]
IPAddressOrRange = AddressPrefix / AddressRange
IPAddressChoice = [ + IPAddressOrRange ] / null
IPAddressFamily = (AFI: uint, IPAddressChoice)
IPAddrBlocks = [ + IPAddressFamily ]
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* IP Resources v2 (id-pe-ipAddrBlocks-v2). Encoded exactly like id-
pe-ipAddrBlocks.
* Signed Certificate Timestamp. If all the SCTs are version v1
[RFC6962], and there are no SCT extensions, the extension value
can be CBOR encoded. LogIDs are encoded as CBOR byte strings, the
timestamp is encoded as a CBOR int (milliseconds since
validityNotBefore), and the signature is encoded with an
(AlgorithmIdentifier, any) pair in the same way as
issuerSignatureAlgorithm and issuerSignatureValue.
SignedCertificateTimestamp = (
logID: bytes,
timestamp: int,
sigAlg: AlgorithmIdentifier,
sigValue: any,
)
SignedCertificateTimestamps = [ + SignedCertificateTimestamp ]
3.3.1. Example Encoding of Extensions
The examples below use values from Section 9.4, Section 9.8, and
Section 9.9:
* 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 ].
* 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" ].
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3.4. COSE Header Parameters
The formatting and processing for c5b, c5c, and c5t, and c5u, defined
in Table 1 are similar to x5bag, x5chain, x5t, x5u defined in
[RFC9360] except that the certificates are C509 instead of DER
encoded X.509 and uses a COSE_C509 structure instead of COSE_X509.
c5u provides an alternative way to identify an untrusted certificate
bag/chain by reference with a URI. The content is a COSE_C509 item
served with the application/cose-c509-cert media type, see
Section 9.13, with corresponding CoAP Content-Format defined in
Section 9.17. A stored file format is defined in [RFC9277], with
"magic number" TBD8 composed of the reserved CBOR tag 55799
concatenated with the CBOR tag calculated from the CoAP Content-
Format value.
The COSE_C509 structure used in c5b, c5c, and c5u is defined as:
COSE_C509 = C509Certificate / [ 2* C509Certificate ]
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 some out-of-band confirmation.
+======+=======+===============+=============================+
| Name | Label | Value Type | Description |
+======+=======+===============+=============================+
| c5b | TBD1 | COSE_C509 | An unordered bag of C509 |
| | | | certificates |
+------+-------+---------------+-----------------------------+
| c5c | TBD2 | COSE_C509 | An ordered chain of C509 |
| | | | certificates |
+------+-------+---------------+-----------------------------+
| c5t | TBD3 | COSE_CertHash | Hash of a C509Certificate |
+------+-------+---------------+-----------------------------+
| c5u | TBD4 | uri | URI pointing to a COSE_C509 |
| | | | containing a ordered chain |
| | | | of certificates |
+------+-------+---------------+-----------------------------+
Table 1: 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.
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3.5. 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:
C509PrivateKey = [
subjectPrivateKeyAlgorithm: AlgorithmIdentifier,
subjectPrivateKey: any,
]
The C509PrivateKey item is served with the application/cose-
c509-privkey media type, see Section 9.15, with corresponding CoAP
Content-Format defined in Section 9.17. A stored file format is
defined in [RFC9277], with "magic number" TBD12 composed of the
reserved CBOR tag 55799 concatenated with the CBOR tag calculated
from the CoAP Content-Format value.
C509PEM = [
C509PrivateKey,
COSE_C509 / null,
]
The C509PEM item is served with the application/cose-c509-pem media
type, see Section 9.16, with corresponding CoAP Content-Format
defined in Section 9.17. A stored file format is defined in
[RFC9277], with "magic number" TBD13 composed of the reserved CBOR
tag 55799 concatenated with the CBOR tag calculated from the CoAP
Content-Format value.
Editor's note: Include further details for encoding of
subjectPrivateKey.
3.6. 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.
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
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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:bstr)-encoding of an extension for which there is an
(extensionID:int, extensionValue:any)-encoding. One reason being
that the certificate was issued before the specific CBOR extension
was registered.
4. C509 Certificate Signing Request
This section defines the format of a C509 Certificate Signing Request
(CSR), also known as a C509 Certificate Request, based on and
compatible with RFC 2986 [RFC2986], and reusing the formatting of
C509 certificates defined in Section 3. The media type is
application/cose-c509-pkcs10, see Section 9.14, with corresponding
CoAP Content-Format defined in Section 9.17. The "magic number" TBD9
is composed of the reserved CBOR tag 55799 concatenated with the CBOR
tag calculated from the CoAP Content-Format value, see [RFC9277].
Different types of C509 Certificate Requests are defined, see
Section 9.2, all using the same CBOR encoding and differing only in
what is being signed and what type of C509 certificate is being
requested:
* The C509 Certificate Request can either be an invertible CBOR re-
encoding of a DER encoded RFC 2986 certification request, or it
can be natively signed where the signature is calculated over the
CBOR encoding instead of the DER encoding.
* The requested C509 certificate in the C509 Certificate Request can
either be of type 2 or of type 3, see Section 9.1.
Combining these options enables the four instances of
c509CertificateRequestType defined in Section 9.2 and illustrated in
Figure 2.
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+------------------+---------------------------------------------------+
| | Requested certificate |
+------------------+=========================+=========================+
| Signed object | c509CertificateType = 2 | c509CertificateType = 3 |
+==================+-------------------------+-------------------------+
| | | |
| CBOR encoded CSR | 0 | 2 |
| | | |
+------------------+-------------------------+-------------------------+
| | | |
| DER encoded CSR | 1 | 3 |
| | | |
+------------------+-------------------------+-------------------------+
Figure 2: C509 Certificate Request Types 0, 1, 2 and 3.
An implementation MAY only support c509CertificateRequestType = 0.
The most common variants are expected to be:
* c509CertificateRequestType = 0. This type indicates that the C509
Certificate Request is natively signed, and that the requested
certificate format has c509CertificateType = 2. This encoding
removes the need for ASN.1 and DER parsing and re-encoding in the
requesting party.
* c509CertificateRequestType = 3. This type indicates that the C509
Certificate Request is CBOR re-encoded RFC 2986 certification
requests, and that the requested certificate formate has
c509CertificateType = 3. This encoding is backwards compatible
with legacy RFC 2986 certification requests and X.509
certificates, but enables a reduced transport overhead.
subjectSignatureAlgorithm can be a signature algorithm or a non-
signature proof-of-possession algorithm, e.g., as defined in
[RFC6955]. In the latter case, the signature is replaced by a MAC
and requires a public Diffie-Hellman key of the verifier distributed
out-of-band. Both kinds are listed in the C509 Signature Algorithms
Registry, see Section 9.10. Note that a key agreement key pair may
be used with a signature algorithm in a certificate request, see
Appendix A.1.3.
Certificate request attributes, i.e. attributes for use with
certificate requests providing additional information about the
subject of the certificate, are defined in Section 5.4 of [RFC2985].
The attribute extensionRequest is supported with a dedicated element.
Other certificate request attributes are included using the same
Extensions structure as in extensionsRequest, both extensions and
attributes are listed in the C509 Extensions Registry, see Figure 9.
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The only other certificate request attribute specified in this
document is challengePassword which is defined for printableString or
utf8String values and encoded as CBOR text string, except if the text
string has an even length ≥ 2 and contains only the symbols '0'–'9'
or 'a'–'f', in which case it is encoded as a CBOR byte string. The
sign of extensionID of challengePassword indicates the string type
(instead the criticalness in other extensions): positive for
utf8String and negative for printableString. In the native
certificate request (types 0 and 2), only utf8String is allowed.
C509CertificateRequest = [
TBSCertificateRequest,
subjectSignatureValue: any,
]
; The elements of the following group are used in a CBOR Sequence:
TBSCertificateRequest = (
c509CertificateRequestType: int,
subjectSignatureAlgorithm: AlgorithmIdentifier,
subject: Name,
subjectPublicKeyAlgorithm: AlgorithmIdentifier,
subjectPublicKey: any,
extensionsRequest: Extensions,
)
challengePassword = tstr / bstr
Figure 3: CDDL for C509CertificateRequest.
After verifying the subjectSignatureValue, the CA MAY transform the
C509CertificateRequest into a [RFC2986] CertificationRequestInfo for
compatibility with existing procedures and code.
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 Certificate Signing Request (CSR) 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].
When a certificate 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.
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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. 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 CSR, the CA transforms it into a DER encoded RFC 2986
CertificationRequestInfo and use 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 the handshake is 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 a constrained wireless
links. The conversion to X.509 within an 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.
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.
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7. Expected Certificate Sizes
The CBOR encoding of the sample certificate chains given in
Appendix A results in the numbers shown in Figure 4 and Figure 5.
COSE_X509 is defined in [RFC9360] and COSE_C509 is defined in
Section 9.12. After RFC 7925 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 will be small, mainly
corresponding to making the ASN.1 encoding more compact. CBOR
encoding can however significantly compress RFC 7925 profiled
certificates. For the example HTTPS certificate chains (www.ietf.org
and tools.ietf.org) both C509 and Brotli perform well complementing
each other. C509 use 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 [RFC7932], the Rust crate Brotli 3.3.0 was
used with compression level 11 and window size 22.
+---------------------------------------+-----------+-----------+
| | COSE_X509 | COSE_C509 |
+---------------------------------------+-----------+-----------+
| RFC 7925 profiled IoT Certificate (1) | 317 | 140 |
+---------------------------------------+-----------+-----------+
| ECDSA HTTPS Certificate Chain (2) | 2193 | 1394 |
+---------------------------------------+-----------+-----------+
| RSA HTTPS Certificate Chain (4) | 5175 | 3934 |
+---------------------------------------+-----------+-----------+
Figure 4: Comparing Sizes of Certificate Chains in COSE. Number
of bytes (length of certificate chain).
+-------------------+-------+----------------+------+---------------+
| | X.509 | X.509 + Brotli | C509 | C509 + Brotli |
+-------------------+-------+----------------+------+---------------+
| RFC 7925 Cert (1) | 327 | 324 | 151 | 167 |
+-------------------+-------+----------------+------+---------------+
| RPKI Cert (1) | 20991 | 9134 | 8660 | 5668 |
+-------------------+-------+----------------+------+---------------+
| HTTPS Chain (2) | 2204 | 1455 | 1414 | 1063 |
+-------------------+-------+----------------+------+---------------+
| HTTPS Chain (4) | 5190 | 3244 | 3958 | 2845 |
+-------------------+-------+----------------+------+---------------+
| HTTPS Bag (8) | 11578 | 3979 | 8882 | 3519 |
+-------------------+-------+----------------+------+---------------+
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Figure 5: Comparing Sizes of Certificate Chains with TLS. Number
of bytes (length of certificate chain). X.509 and C509 are
Certificate messages. X.509 + Brotli and C509 + Brotli are
CompressedCertificate messages.
8. Security Considerations
The CBOR profiling 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 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.
The mechanism in this draft does not reveal any additional
information compared to X.509. Because of difference in size, it
will be possible to detect that this profile is used. The gateway
solution described in Section 6 requires unencrypted certificates and
is not recommended.
9. IANA Considerations
This document creates several new registries under the new heading
"CBOR Encoded X.509 (C509) Parameters". For all items, the
'Reference' field points to this document.
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 one 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
encodings, other values in the interval [-256, 255] have a 2 byte
encodings, and the remaining values in the interval [-65536, 65535]
have 3 byte encodings.
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9.1. C509 Certificate Types Registry
IANA has created a new registry titled "C509 Certificate Types" under
the new heading "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. 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:
+-------+-----------------------------------------------------------+
| Value | Description |
+=======+===========================================================+
| 0 | Reserved |
+-------+-----------------------------------------------------------+
| 1 | Reserved |
+-------+-----------------------------------------------------------+
| 2 | Natively Signed C509 Certificate following X.509 v3 |
+-------+-----------------------------------------------------------+
| 3 | CBOR re-encoding of X.509 v3 Certificate |
+-------+-----------------------------------------------------------+
Figure 6: C509 Certificate Types
9.2. C509 Certificate Request Types Registry
IANA has created a new registry titled "C509 Certificate Request
Types" under the new heading "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.
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 | Requested certificate is C509 Type 2. |
| | Natively Signed C509 Certificate Request. |
+-------+-----------------------------------------------------------+
| 1 | Requested certificate is C509 Type 2. |
| | CBOR re-encoding of RFC 2986 certification request. |
+-------+-----------------------------------------------------------+
| 2 | Requested certificate is C509 Type 3. |
| | Natively Signed C509 Certificate Request. |
+-------+-----------------------------------------------------------+
| 3 | Requested certificate is C509 Type 3. |
| | CBOR re-encoding of RFC 2986 certification request. |
+-------+-----------------------------------------------------------+
Figure 7: C509 Certificate Request Types
9.3. C509 Attributes Registry
IANA has created a new registry titled "C509 Attributes" under the
new heading "CBOR Encoded X.509 (C509) Parameters". The columns 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. For values in the interval [0, 23] the
registration procedure is "IETF Review" and "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. The OID is given in dotted decimal
representation. The DER column contains the hex string of the DER-
encoded OID [X.690].
The initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | 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: |
+-------+-----------------------------------------------------------+
| 1 | Name: Common Name |
| | Identifiers: commonName, cn |
| | OID: 2.5.4.3 |
| | DER: 06 03 55 04 03 |
| | Comments: |
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+-------+-----------------------------------------------------------+
| 2 | Name: Surname |
| | Identifiers: surname, sn |
| | OID: 2.5.4.4 |
| | DER: 06 03 55 04 04 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 3 | Name: Serial Number |
| | Identifiers: serialNumber |
| | OID: 2.5.4.5 |
| | DER: 06 03 55 04 05 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 4 | Name: Country |
| | Identifiers: countryName, c |
| | OID: 2.5.4.6 |
| | DER: 06 03 55 04 06 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 5 | Name: Locality |
| | Identifiers: localityName, locality, l |
| | OID: 2.5.4.7 |
| | DER: 06 03 55 04 07 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 6 | Name: State or Province |
| | Identifiers: stateOrProvinceName, st |
| | OID: 2.5.4.8 |
| | DER: 06 03 55 04 08 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 7 | Name: Street Address |
| | Identifiers: streetAddress, street |
| | OID: 2.5.4.9 |
| | DER: 06 03 55 04 09 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 8 | Name: Organization |
| | Identifiers: organizationName, o |
| | OID: 2.5.4.10 |
| | DER: 06 03 55 04 0A |
| | Comments: |
+-------+-----------------------------------------------------------+
| 9 | Name: Organizational Unit |
| | Identifiers: organizationalUnitName, ou |
| | OID: 2.5.4.11 |
| | DER: 06 03 55 04 0B |
| | Comments: |
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+-------+-----------------------------------------------------------+
| 10 | Name: Title |
| | Identifiers: title |
| | OID: 2.5.4.12 |
| | DER: 06 03 55 04 0C |
| | Comments: |
+-------+-----------------------------------------------------------+
| 11 | Name: Business Category |
| | Identifiers: businessCategory |
| | OID: 2.5.4.15 |
| | DER: 06 03 55 04 0F |
| | Comments: |
+-------+-----------------------------------------------------------+
| 12 | Name: Postal Code |
| | Identifiers: postalCode |
| | OID: 2.5.4.17 |
| | DER: 06 03 55 04 11 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 13 | Name: Given Name |
| | Identifiers: givenName |
| | OID: 2.5.4.42 |
| | DER: 06 03 55 04 2A |
| | Comments: |
+-------+-----------------------------------------------------------+
| 14 | Name: Initials |
| | Identifiers: initials |
| | OID: 2.5.4.43 |
| | DER: 06 03 55 04 2B |
| | Comments: |
+-------+-----------------------------------------------------------+
| 15 | Name: Generation Qualifier |
| | Identifiers: generationQualifier |
| | OID: 2.5.4.44 |
| | DER: 06 03 55 04 2C |
| | Comments: |
+-------+-----------------------------------------------------------+
| 16 | Name: DN Qualifier |
| | Identifiers: dnQualifier |
| | OID: 2.5.4.46 |
| | DER: 06 03 55 04 2E |
| | Comments: |
+-------+-----------------------------------------------------------+
| 17 | Name: Pseudonym |
| | Identifiers: pseudonym |
| | OID: 2.5.4.65 |
| | DER: 06 03 55 04 41 |
| | Comments: |
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+-------+-----------------------------------------------------------+
| 18 | Name: Organization Identifier |
| | Identifiers: organizationIdentifier |
| | OID: 2.5.4.97 |
| | DER: 06 03 55 04 61 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 19 | Name: Inc. Locality |
| | Identifiers: jurisdictionOfIncorporationLocalityName |
| | 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: |
+-------+-----------------------------------------------------------+
| 20 | Name: Inc. State or Province |
| | Identifiers: jurisdictionOfIncorporation |
| | StateOrProvinceName |
| | 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: |
+-------+-----------------------------------------------------------+
| 21 | Name: Inc. Country |
| | Identifiers: jurisdictionOfIncorporationCountryName |
| | 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: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 24 | Name: Postal Address |
| | Identifiers: postalAddress |
| | OID: 2.5.4.16 |
| | DER: 06 03 55 04 10 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 25 | Name: Name |
| | Identifiers: name |
| | OID: 2.5.4.41 |
| | DER: 06 03 55 04 29 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 26 | Name: Telephone Number |
| | Identifiers: telephoneNumber |
| | OID: 2.5.4.20 |
| | DER: 06 03 55 04 14 |
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| | Comments: |
+-------+-----------------------------------------------------------+
| 27 | Name: Directory Management Domain Name |
| | Identifiers: dmdName |
| | OID: 2.5.4.54 |
| | DER: 06 03 55 04 36 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 29 | Name: Unstructured Name |
| | Identifiers: unstructuredName |
| | OID: 1.2.840.113549.1.9.2 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
Figure 8: C509 Attributes
9.4. C509 Extensions Registry
IANA has created a new registry titled "C509 Extensions Registry"
under the new heading "CBOR Encoded X.509 (C509) Parameters". The
columns of the registry are Value, Name, Identifiers, OID, DER,
Comments, extensionValue, and Reference, where Value is an positive
integer, and the other columns are text strings. The registry also
contains CSR attributes for use in Certificate Requests, see
Section 4. For values in the interval [1, 23] the registration
procedure is "IETF Review" and "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:
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+-------+-----------------------------------------------------------+
| Value | Extension |
+=======+===========================================================+
| 1 | Name: Subject Key Identifier |
| | Identifiers: subjectKeyIdentifier |
| | OID: 2.5.29.14 |
| | DER: 06 03 55 1D 0E |
| | Comments: |
| | extensionValue: SubjectKeyIdentifier |
+-------+-----------------------------------------------------------+
| 2 | Name: Key Usage |
| | Identifiers: keyUsage |
| | OID: 2.5.29.15 |
| | DER: 06 03 55 1D 0F |
| | Comments: |
| | AttributeValue: KeyUsage |
+-------+-----------------------------------------------------------+
| 3 | Name: Subject Alternative Name |
| | Identifiers: subjectAltName |
| | OID: 2.5.29.17 |
| | DER: 06 03 55 1D 11 |
| | Comments: |
| | extensionValue: SubjectAltName |
+-------+-----------------------------------------------------------+
| 4 | Name: Basic Constraints |
| | Identifiers: basicConstraints |
| | OID: 2.5.29.19 |
| | DER: 06 03 55 1D 13 |
| | Comments: |
| | extensionValue: BasicConstraints |
+-------+-----------------------------------------------------------+
| 5 | Name: CRL Distribution Points |
| | Identifiers: cRLDistributionPoints |
| | OID: 2.5.29.31 |
| | DER: 06 03 55 1D 1F |
| | Comments: |
| | extensionValue: CRLDistributionPoints |
+-------+-----------------------------------------------------------+
| 6 | Name: Certificate Policies |
| | Identifiers: certificatePolicies |
| | OID: 2.5.29.32 |
| | DER: 06 03 55 1D 20 |
| | Comments: |
| | extensionValue: CertificatePolicies |
+-------+-----------------------------------------------------------+
| 7 | Name: Authority Key Identifier |
| | Identifiers: authorityKeyIdentifier |
| | OID: 2.5.29.35 |
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| | DER: 06 03 55 1D 23 |
| | Comments: |
| | extensionValue: AuthorityKeyIdentifier |
+-------+-----------------------------------------------------------+
| 8 | Name: Extended Key Usage |
| | Identifiers: extKeyUsage |
| | OID: 2.5.29.37 |
| | DER: 06 03 55 1D 25 |
| | Comments: |
| | 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: |
| | extensionValue: AuthorityInfoAccessSyntax |
+-------+-----------------------------------------------------------+
| 10 | Name: Signed Certificate Timestamp List |
| | Identifiers: |
| | OID: 1.3.6.1.4.1.11129.2.4.2 |
| | DER: 06 0A 2B 06 01 04 01 D6 79 02 04 02 |
| | Comments: |
| | extensionValue: SignedCertificateTimestamps |
+-------+-----------------------------------------------------------+
| 24 | Name: Subject Directory Attributes |
| | Identifiers: subjectDirectoryAttributes |
| | OID: 2.5.29.9 |
| | DER: 06 03 55 1D 09 |
| | Comments: |
| | extensionValue: SubjectDirectoryAttributes |
+-------+-----------------------------------------------------------+
| 25 | Name: Issuer Alternative Name |
| | Identifiers: issuerAltName |
| | OID: 2.5.29.18 |
| | DER: 06 03 55 1D 12 |
| | Comments: |
| | extensionValue: IssuerAltName |
+-------+-----------------------------------------------------------+
| 26 | Name: Name Constraints |
| | Identifiers: nameConstraints |
| | OID: 2.5.29.30 |
| | DER: 06 03 55 1D 1E |
| | Comments: |
| | extensionValue: NameConstraints |
+-------+-----------------------------------------------------------+
| 27 | Name: Policy Mappings |
| | Identifiers: policyMappings |
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| | OID: 2.5.29.33 |
| | DER: 06 03 55 1D 21 |
| | Comments: |
| | extensionValue: PolicyMappings |
+-------+-----------------------------------------------------------+
| 28 | Name: Policy Constraints |
| | Identifiers: policyConstraints |
| | OID: 2.5.29.36 |
| | DER: 06 03 55 1D 24 |
| | Comments: |
| | extensionValue: PolicyConstraints |
+-------+-----------------------------------------------------------+
| 29 | Name: Freshest CRL |
| | Identifiers: freshestCRL |
| | OID: 2.5.29.46 |
| | DER: 06 03 55 1D 2E |
| | Comments: |
| | extensionValue: FreshestCRL |
+-------+-----------------------------------------------------------+
| 30 | Name: Inhibit anyPolicy |
| | Identifiers: inhibitAnyPolicy |
| | OID: 2.5.29.54 |
| | DER: 06 03 55 1D 36 |
| | Comments: |
| | 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: |
| | extensionValue: SubjectInfoAccessSyntax |
+-------+-----------------------------------------------------------+
| 32 | Name: IP Resources |
| | 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: |
| | extensionValue: IPAddrBlocks |
+-------+-----------------------------------------------------------+
| 33 | Name: AS Resources |
| | 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: |
| | extensionValue: ASIdentifiers |
+-------+-----------------------------------------------------------+
| 34 | Name: IP Resources v2 |
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| | 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: |
| | extensionValue: IPAddrBlocks |
+-------+-----------------------------------------------------------+
| 35 | Name: AS Resources 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: |
| | extensionValue: ASIdentifiers |
+-------+-----------------------------------------------------------+
| 36 | Name: Biometric Information |
| | Identifiers: id-pe-biometricInfo |
| | OID: 1.3.6.1.5.5.7.1.2 |
| | DER: 06 08 2B 06 01 05 05 07 01 02 |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 37 | Name: Precertificate Signing Certificate |
| | 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: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 38 | Name: OCSP No Check |
| | Identifiers: id-pkix-ocsp-nocheck |
| | OID: 1.3.6.1.5.5.7.48.1.5 |
| | DER: 06 09 2B 06 01 05 05 07 30 01 05 |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 39 | Name: Qualified Certificate Statements |
| | Identifiers: id-pe-qcStatements |
| | OID: 1.3.6.1.5.5.7.1.3 |
| | DER: 06 08 2B 06 01 05 05 07 01 03 |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 40 | Name: S/MIME Capabilities |
| | Identifiers: smimeCapabilities |
| | OID: 1.2.840.113549.1.9.15 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 0F |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
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| 41 | 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: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 255 | 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: CSR Attribute |
| | extensionValue: ChallengePassword |
+-------+-----------------------------------------------------------+
Figure 9: C509 Extensions and CSR Attributes
9.5. C509 Certificate Policies Registry
IANA has created a new registry titled "C509 Certificate Policies
Registry" under the new heading "CBOR Encoded X.509 (C509)
Parameters". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. For values in the
interval [-24, 23] the registration procedure is "IETF Review" and
"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: |
+-------+-----------------------------------------------------------+
| 1 | Name: Domain Validation (DV) |
| | Identifiers: domain-validated |
| | OID: 2.23.140.1.2.1 |
| | DER: 06 06 67 81 0C 01 02 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 2 | Name: Organization Validation (OV) |
| | Identifiers: organization-validated |
| | OID: 2.23.140.1.2.2 |
| | DER: 06 06 67 81 0C 01 02 02 |
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| | Comments: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 4 | Name: Extended Validation (EV) |
| | Identifiers: ev-guidelines |
| | OID: 2.23.140.1.1 |
| | DER: 06 05 67 81 0C 01 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 10 | 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: |
+-------+-----------------------------------------------------------+
| 11 | Name: Remote SIM Provisioning Role |
| | eUICC |
| | Identifiers: id-rspRole-euicc |
| | OID: 2.23.146.1.2.1.1 |
| | DER: 06 07 67 81 12 01 02 01 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 12 | Name: Remote SIM Provisioning Role |
| | eUICC Manufacturer |
| | Identifiers: id-rspRole-eum |
| | OID: 2.23.146.1.2.1.2 |
| | DER: 06 07 67 81 12 01 02 01 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 13 | Name: Remote SIM Provisioning Role |
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| | SM-DP+ TLS |
| | Identifiers: id-rspRole-dp-tls |
| | OID: 2.23.146.1.2.1.3 |
| | DER: 06 07 67 81 12 01 02 01 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 14 | Name: Remote SIM Provisioning Role |
| | SM-DP+ Authentication |
| | Identifiers: id-rspRole-dp-auth |
| | OID: 2.23.146.1.2.1.4 |
| | DER: 06 07 67 81 12 01 02 01 04 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 15 | Name: Remote SIM Provisioning Role |
| | SM-DP+ Profile Binding |
| | Identifiers: id-rspRole-dp-pb |
| | OID: 2.23.146.1.2.1.5 |
| | DER: 06 07 67 81 12 01 02 01 05 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 16 | Name: Remote SIM Provisioning Role |
| | SM-DS TLS |
| | Identifiers: id-rspRole-ds-tls |
| | OID: 2.23.146.1.2.1.6 |
| | DER: 06 07 67 81 12 01 02 01 06 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 17 | Name: Remote SIM Provisioning Role |
| | SM-DS Authentication |
| | Identifiers: id-rspRole-ds-auth |
| | OID: 2.23.146.1.2.1.7 |
| | DER: 06 07 67 81 12 01 02 01 07 |
| | Comments: |
+-------+-----------------------------------------------------------+
Figure 10: C509 Certificate Policies
9.6. C509 Policies Qualifiers Registry
IANA has created a new registry titled "C509 Policies Qualifiers
Registry" under the new heading "CBOR Encoded X.509 (C509)
Parameters". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. For values in the
interval [-24, 23] the registration procedure is "IETF Review" and
"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:
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+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
Figure 11: C509 Policies Qualifiers
9.7. C509 Information Access Registry
IANA has created a new registry titled "C509 Information Access
Registry" under the new heading "CBOR Encoded X.509 (C509)
Parameters". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. 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 | 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: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 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 12: C509 Information Accesses
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9.8. C509 Extended Key Usages Registry
IANA has created a new registry titled "C509 Extended Key Usages
Registry" under the new heading "CBOR Encoded X.509 (C509)
Parameters". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. For values in the
interval [-24, 23] the registration procedure is "IETF Review" and
"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 |
| | OID: 1.3.6.1.5.5.7.3.8 |
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| | DER: 06 08 2B 06 01 05 05 07 03 08 |
| | Comments: |
+-------+---------------------------------------------------------+
| 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 |
| | OID: 1.3.6.1.5.5.7.3.28 |
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| | 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 |
+-------+---------------------------------------------------------+
Figure 13: C509 Extended Key Usages
9.9. C509 General Names Registry
IANA has created a new registry titled "C509 General Names Registry"
under the new heading "CBOR Encoded X.509 (C509) Parameters". The
columns of the registry are Value, General Name, and Reference, where
Value is an integer, and the other columns are text strings. 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 | General Names |
+=======+===========================================================+
| -2 | Name: otherName with SmtpUTF8Mailbox |
| | Comments: id-on-SmtpUTF8Mailbox |
| | (1.3.6.1.5.5.7.8.9) |
| | 06 08 2B 06 01 05 05 07 08 09 |
| | Value: text |
+-------+-----------------------------------------------------------+
| -1 | Name: otherName with hardwareModuleName |
| | Comments: id-on-hardwareModuleName |
| | (1.3.6.1.5.5.7.8.4) |
| | 06 08 2B 06 01 05 05 07 08 04 |
| | Value: [ ~oid, bytes ] |
+-------+-----------------------------------------------------------+
| 0 | Name: otherName |
| | Comments: |
| | Value: [ ~oid, bytes ] |
+-------+-----------------------------------------------------------+
| 1 | Name: rfc822Name |
| | Comments: |
| | Value: text |
+-------+-----------------------------------------------------------+
| 2 | Name: dNSName |
| | Comments: |
| | Value: text |
+-------+-----------------------------------------------------------+
| 4 | Name: directoryName |
| | Comments: |
| | Value: Name |
+-------+-----------------------------------------------------------+
| 6 | Name: uniformResourceIdentifier |
| | Comments: |
| | Value: text |
+-------+-----------------------------------------------------------+
| 7 | Name: iPAddress |
| | Comments: |
| | Value: bytes |
+-------+-----------------------------------------------------------+
| 8 | Name: registeredID |
| | Comments: |
| | Value: ~oid |
+-------+-----------------------------------------------------------+
Figure 14: C509 General Names
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9.10. C509 Signature Algorithms Registry
IANA has created a new registry titled "C509 Signature Algorithms"
under the new heading "CBOR Encoded X.509 (C509) Parameters". The
registry includes both signature algorithms and non-signature proof-
of-possession algorithms. The columns 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.
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:
+-------+-----------------------------------------------------------+
| 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. Compressed signature value |
+-------+-----------------------------------------------------------+
| 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: Compressed signature value |
+-------+-----------------------------------------------------------+
| 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: Compressed signature value |
+-------+-----------------------------------------------------------+
| 2 | Name: ECDSA with SHA-512 |
| | Identifiers: ecdsa-with-SHA512 |
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| | OID: 1.2.840.10045.4.3.4 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 86 48 CE 3D 04 03 04 |
| | Comments: Compressed signature value |
+-------+-----------------------------------------------------------+
| 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: Compressed signature value |
+-------+-----------------------------------------------------------+
| 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: Compressed signature value |
+-------+-----------------------------------------------------------+
| 12 | Name: Ed25519 |
| | Identifiers: id-Ed25519, id-EdDSA25519 |
| | OID: 1.3.101.112 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 70 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 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: SHA-256 with 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 public static Diffie-Hellman key. |
+-------+-----------------------------------------------------------+
| 15 | Name: SHA-384 with 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 |
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| | KDF and MAC, see RFC 6955. Requires |
| | recipient public static Diffie-Hellman key. |
+-------+-----------------------------------------------------------+
| 16 | Name: SHA-512 with 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 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: |
+-------+-----------------------------------------------------------+
| 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 |
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| | 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: |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 42 | Name: HSS / LMS |
| | Identifiers: id-alg-hss-lms-hashsig, id-alg-mts-hashsig |
| | OID: 1.2.840.113549.1.9.16.3.17 |
| | Parameters: Absent |
| | DER: 30 0D 06 0B 2A 86 48 86 F7 0D 01 09 10 03 11 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 43 | Name: XMSS |
| | Identifiers: id_alg_xmss |
| | OID: 0.4.0.127.0.15.1.1.13.0 |
| | Parameters: Absent |
| | DER: 30 0B 06 09 04 00 7F 00 0F 01 01 0D 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 44 | Name: XMSS^MT |
| | Identifiers: id_alg_xmssmt |
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| | OID: 0.4.0.127.0.15.1.1.14.0 |
| | Parameters: Absent |
| | DER: 30 0B 06 09 04 00 7F 00 0F 01 01 0E 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 45 | 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: Compressed signature value |
+-------+-----------------------------------------------------------+
Figure 15: C509 Signature Algorithms
9.11. C509 Public Key Algorithms Registry
IANA has created a new registry titled "C509 Public Key Algorithms"
under the new heading "CBOR Encoded X.509 (C509) Parameters". The
columns 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. 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". T 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: Point 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 |
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| | Parameters: namedCurve = secp384r1 (1.3.132.0.34) |
| | DER: 30 10 06 07 2A 86 48 CE 3D 02 01 06 05 2B 81 |
| | 04 00 22 |
| | Comments: Point 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: Point compressed subjectPublicKey |
| | Also known as P-521, ansip521r1 |
+-------+-----------------------------------------------------------+
| 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: |
+-------+-----------------------------------------------------------+
| 10 | 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: |
+-------+-----------------------------------------------------------+
| 11 | Name: Ed448 (Edwards) |
| | Identifiers: id-Ed448, id-EdDSA448 |
| | OID: 1.3.101.113 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 71 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 16 | Name: HSS / LMS |
| | Identifiers: id-alg-hss-lms-hashsig, id-alg-mts-hashsig |
| | OID: 1.2.840.113549.1.9.16.3.17 |
| | Parameters: Absent |
| | DER: 30 0D 06 0B 2A 86 48 86 F7 0D 01 09 10 03 11 |
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| | Comments: |
+-------+-----------------------------------------------------------+
| 17 | Name: XMSS |
| | Identifiers: id_alg_xmss |
| | OID: 0.4.0.127.0.15.1.1.13.0 |
| | Parameters: Absent |
| | DER: 30 0B 06 09 04 00 7F 00 0F 01 01 0D 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 18 | Name: XMSS^MT |
| | Identifiers: id_alg_xmssmt |
| | OID: 0.4.0.127.0.15.1.1.14.0 |
| | Parameters: Absent |
| | DER: 30 0B 06 09 04 00 7F 00 0F 01 01 0E 00 |
| | 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: Point 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: Point 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: Point compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 27 | Name: EC Public Key (Weierstraß) with |
| | FRP256v1 |
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| | 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: Point compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 28 | 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: Point compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
Figure 16: C509 Public Key Algorithms
9.11.1. Suitability of different public key algorithms for use within
IoT scenarios
The public key algorithms registry Section 9.11 specify 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. These curves are represented by ids 1–11 and 24–28
in Section 9.11.
9.12. COSE Header Parameters Registry
IANA is requested to assign the entries in Table 1 to the "COSE
Header Parameters" registry under the "CBOR Object Signing and
Encryption (COSE)" heading with this document as reference.
9.13. 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.
IANA has registered the following media type [RFC6838]:
Type name: application
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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.
* 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
* 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: IESG
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9.14. Media Type application/cose-c509-pkcs10
When the application/cose-c509-pkcs10 media type is used, the data is
a C509CertificateRequest structure.
IANA has registered the following media type [RFC6838]:
Type name: application
Subtype name: cose-c509-pkcs10
Required parameters: N/A
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 Certificate 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
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9.15. Media Type application/cose-c509-privkey
When the application/cose-c509-privkey media type is used, the data
is a C509PrivateKey structure.
IANA has registered the following media type [RFC6838]:
Type name: application
Subtype name: cose-c509-privkey
Required parameters: N/A
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
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9.16. Media Type application/cose-c509-pem
When the application/cose-c509-pem media type is used, the data is a
C509PEM structure.
IANA has registered the following media type [RFC6838]:
Type name: application
Subtype name: cose-c509-pem
Required parameters: N/A
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
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9.17. CoAP Content-Formats Registry
IANA is requested to add the media types "application/cose-
c509-cert", "application/cose-c509-pkcs10", "application/cose-
c509-privkey" and "application/cose-c509-pem" to the "CoAP Content-
Formats" registry under the registry group "Constrained RESTful
Environments (CoRE) Parameters".
+--------------------------------+----------+-------+-------------------+
| Media Type | Encoding | ID | Reference |
+================================+==========+=======+===================+
| application/cose-c509-cert | - | TBD6 | [[this document]] |
| application/cose-c509-pkcs10 | - | TBD7 | [[this document]] |
| application/cose-c509-privkey | - | TBD10 | [[this document]] |
| application/cose-c509-pem | - | TBD11 | [[this document]] |
+--------------------------------+----------+-------+-------------------+
Figure 17: CoAP Content-Format IDs
9.18. TLS Certificate Types Registry
This document registers the following entry in the "TLS Certificate
Types" registry under the "Transport Layer Security (TLS) Extensions"
heading. The new certificate type can be used with additional TLS
certificate compression [RFC8879]. C509 is defined in the same way
as as X.509, but uses a different value and instead of DER-encoded
X.509 certificate, opaque cert_data<1..2^24-1> contains a the CBOR
sequence ~C509Certificate (an unwrapped C509Certificate).
Editor's Note: The TLS registrations should be discussed and approved
by the TLS WG at a later stage. The TLS WG might e.g. want a
separate draft in the TLS WG.
+-------+------------------+-------------+--------------------------+
| Value | Name | Recommended | Comment |
+=======+==================+=============+==========================+
| TBD5 | C509 Certificate | Y | |
+-------+------------------+-------------+--------------------------+
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9.19. CBOR Tags Registry
This document registers the following entries in the "CBOR Tags"
registry under the "Concise Binary Object Representation (CBOR) Tags"
heading.
+------+------------------------------------------------------------+
| Tag | X.509 Public Key Algorithms |
+======+============================================================+
| TBD6 | Data Item: COSE_C509 |
| | Semantics: An ordered chain of C509 certificates |
| | Reference: This document |
+------+------------------------------------------------------------+
9.20. TLSA Selectors Registry
This document registers the following entries in the "TLSA Selectors"
registry under the "DNS-Based Authentication of Named Entities (DANE)
Parameters" heading.
+-------+---------+--------------------------------+-------------------+
| Value | Acronym | Short Description | Reference |
+=======+=========+================================+===================+
| TBD7 | C509 | CBOR encoded PKIX certificates | [[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, which are essentially CBOR encoded PKIX certificates.
9.21. EDHOC Authentication Credential Types Registry
This document registers the following entry in the "EDHOC
Authentication Credential Types" registry under the "Ephemeral
Diffie-Hellman Over COSE (EDHOC)" heading. This is used to identify
supported authentication credential type, for example, during
discovery of EDHOC resources, see [RFC9668].
+-------+----------------------+-------------------+
| Value | Description | Reference |
+=======+======================+===================+
| TBD14 | C509 certificate | [[this document]] |
+-------+----------------------+-------------------+
10. References
10.1. Normative References
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[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>.
[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>.
[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>.
[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>.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13,
RFC 6838, DOI 10.17487/RFC6838, January 2013,
<https://www.rfc-editor.org/rfc/rfc6838>.
[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>.
[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>.
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[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>.
[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>.
[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>.
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[SECG] "Elliptic Curve Cryptography, Standards for Efficient
Cryptography Group, ver. 2", 2009,
<https://secg.org/sec1-v2.pdf>.
[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>.
10.2. Informative References
[CAB-Code] CA/Browser Forum, "CA/Browser Forum, "Baseline
Requirements for the Issuance and Management of Publicly-
Trusted Code Signing Certificates Version 2.3"", May 2021,
<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 1.7.6"", June 2021,
<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 2.1",
February 2021, <https://www.gsma.com/esim/wp-
content/uploads/2021/02/SGP.14-v2.1.pdf>.
[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>.
[I-D.ietf-uta-tls13-iot-profile]
Tschofenig, H., Fossati, T., and M. Richardson, "TLS/DTLS
1.3 Profiles for the Internet of Things", Work in
Progress, Internet-Draft, draft-ietf-uta-tls13-iot-
profile-13, 3 March 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-uta-
tls13-iot-profile-13>.
[IEEE-802.1AR]
Institute of Electrical and Electronics Engineers, "IEEE
Standard for Local and metropolitan area networks–Secure
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Device Identity", IEEE Standard 802.1AR-2018 , August
2018,
<https://standards.ieee.org/standard/802_1AR-2018.html>.
[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>.
[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>.
[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>.
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[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>.
[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. Example C509 Certificates
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A.1. Example RFC 7925 profiled X.509 Certificate
Example of [RFC7925] profiled X.509 certificate parsed with OpenSSL.
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.
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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
A.1.1. Example C509 Certificate Encoding
The CBOR encoding (~C509Certificate) of the same X.509 certificate is
shown below in CBOR diagnostic format.
/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'
The size of the CBOR encoding (CBOR sequence) is 140 bytes. The
point compressed public key is represented as described in
Section 3.2.1.
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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
A.1.2. Example: Natively Signed C509 Certificate
The corresponding natively signed C509 certificate in CBOR diagnostic
format is identical, except for c509CertificateType, encoding of
point compression (see Section 3.2.1), and signatureValue.
/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'
The size of the CBOR encoding (CBOR sequence) is 140 bytes.
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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
A.1.3. C509 for Diffie-Hellman keys
The two previous examples illustrate the common key usage
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 certificate 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'
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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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Internet-Draft C509 Certificates March 2025
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.
Preuß Mattsson, et al. Expires 4 September 2025 [Page 69]
Internet-Draft C509 Certificates March 2025
/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'FDC8B421F11C25E47E3AC57123BF2D9FDC494F028BC351CC80C03F150BF50CFF95',
[
4, -2,
1, h'96600D8716BF7FD0E752D0AC760777AD665D02A0',
7, h'68D16551F951BFC82A431D0D9F08BC2D205B1160',
-2, 5,
3, [-1, [h'2B06010401B43B0A01', h'01020304']]
/ subjectAltName with hardwareModuleName /
],
h'C0D81996D2507D693F3C48EAA5EE9491BDA6DB214099D98117C63B361374CD86A7
74989F4C321A5CF25D832A4D336A08AD67DF20F1506421188A0ADE6D349236'
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 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 00 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
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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"
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],
1,
h'FD963ECDD84DCD1B93A1CF432D1A7217D6C63BDE3355A02F8CFB5AD8994CD44E20',
[
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",
"http://crl4.digicert.com/CloudflareIncECCCA-3.crl"],
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,
10, [
h'F65C942FD1773022145418083094568EE34D131933BFDF0C2F200BCC4EF164E3',
77922190,
0,
h'F8D1B4A93D2F0D4C4176DFB488BCC73B86443D7DE00E6AC8174D8948A8843668
29FF5A34068A240C69502788E8EE25AB7ED2CBCF686ECE7B5F96B431A90702FA',
h'5CDC4392FEE6AB4544B15E9AD456E61037FBD5FA47DCA17394B25EE6F6C70ECA',
77922238,
0,
h'E891C197BFB0E3D30CB6CEE60D94C3C75FD1175336931108D89812D4D29D81D0
A159D16C4647D1483757FCD6CE4E75EC7B5EF657EFE028F8E5CC4792682DAC43'
]
],
h'BD63CF4F7E5CFE6C29385EA71CFBFC1E3F7B1CD07251A221F77769C0F471DFEA
B5C06CC45854FA30B28288B1D3BB9A6661ED5031725B1A8202E0DA5B59F95402'
The size of the CBOR encoding (CBOR sequence) is 783 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
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
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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
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
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Internet-Draft C509 Certificates March 2025
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
7C72B346EBC1E878B80FCBE1EBBD064458DC8350B2A0625BDC81B836E39E7C79
B2A9538AE00BC94A2A13393113BD2CCFA870CF8C8D3D01A388AE1200361D1E24
2BDD79D8530126ED284FC98694834EC8E1142E85B3AFD46EDD6946AF41250E7A
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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',
10, [
h'F65C942FD1773022145418083094568EE34D131933BFDF0C2F200BCC4EF164E3',
1715,
0,
h'8CF54852CE5635433911CF10CDB91F52B33639223AD138A41DECA6FEDE1FE90F
BCA2254366C19A2691C47A00B5B653ABBD44C2F8BAAEF4D2DAF2527CE6454995',
h'5CDC4392FEE6AB4544B15E9AD456E61037FBD5FA47DCA17394B25EE6F6C70ECA',
2012,
0,
h'A5E0906E63E91D4FDDEFFF0352B91E50896007564B448A3828F596DC6B28726D
FC91EAED02168866054EE18A2E5346C4CC51FEB3FA10A91D2EDBF99125F86CE6'
]
],
h'14043FA0BED2EE3FA86E3A1F788EA04C35530F11061FFF60A16D0B83E9D92ADB
B33F9DB3D7E0594C19A8E419A50CA770727763D5FE64510AD27AD650A58A9238
ECCB2F0F5AC064584D5C06B9736368278B8934DC79C71D3AFD345F8314415849
80682980398A867269CC7937CEE397F7DCF39588ED81032900D2A2C7BAABD63A
8ECA090BD9FB39264BFF03D88E2D3F6B21CA8A7DD85FFB94BA83DE9CFC158D61
FA672DB0C7DB3D250A414A85D37F4946373CF4B175D052F3DDC766F14BFDAA00
EDBFE47EED01EC7BE4F646FC31FD72FE03D2F265AF4D7EE2819B7AFD303CF552
F40534A08A3E194158C8A8E05171840915AEECA57775FA18F7D577D531CCC72D'
The size of the CBOR encoding (CBOR sequence) is 1245 bytes.
Acknowledgments
The authors want to thank Henk Birkholz, Carsten Bormann, Russ
Housley, Olle Johansson, Benjamin Kaduk, Ilari Liusvaara, Laurence
Lundblade, Francesca Palombini, Thomas Peterson, Michael Richardson,
Stefan Santesson, Jim Schaad, Brian Sipos, Fraser Tweedale, and Rene
Struik for reviewing and commenting on intermediate versions of the
draft and help with GitHub.
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Contributors
Special acknowledgement goes to Lijun Liao for his careful review and
many detailed improvement proposals.
Authors' Addresses
John Preuß Mattsson
Ericsson AB
Email: john.mattsson@ericsson.com
Göran Selander
Ericsson AB
Email: goran.selander@ericsson.com
Shahid Raza
RISE AB
Email: shahid.raza@ri.se
Joel Höglund
RISE AB
Email: joel.hoglund@ri.se
Martin Furuhed
Nexus Group
Email: martin.furuhed@nexusgroup.com
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