Internet DRAFT - draft-mattsson-cose-cbor-cert-compress
draft-mattsson-cose-cbor-cert-compress
Network Working Group S. Raza
Internet-Draft J. Hoeglund
Intended status: Standards Track RISE AB
Expires: August 26, 2021 G. Selander
J. Mattsson
Ericsson AB
M. Furuhed
Nexus Group
February 22, 2021
CBOR Encoded X.509 Certificates (C509 Certificates)
draft-mattsson-cose-cbor-cert-compress-08
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 significantly
reduces the size of certificates compatible with e.g. RFC 7925, IEEE
802.1AR (DevID), CNSA, and CA/Browser Forum Baseline Requirements.
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%. The CBOR encoded structure can
alternatively be signed directly ("natively signed"), which does not
require re-encoding for the signature to be verified. The document
also specifies COSE headers as well as a TLS certificate type for
C509 certificates.
NOTE: "C509" is a placeholder, name to be decided by the COSE WG.
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
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on August 26, 2021.
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Copyright Notice
Copyright (c) 2021 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
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Notational Conventions . . . . . . . . . . . . . . . . . . . 4
3. CBOR Encoding . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Message Fields . . . . . . . . . . . . . . . . . . . . . 5
3.2. Encoding of subjectPublicKey and issuerSingatureValue . . 8
3.3. Encoding of Extensions . . . . . . . . . . . . . . . . . 9
4. Compliance Requirements for Constrained IoT . . . . . . . . . 11
5. Legacy Considerations . . . . . . . . . . . . . . . . . . . . 11
6. Expected Certificate Sizes . . . . . . . . . . . . . . . . . 12
7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
8.1. C509 Certificate Types Registry . . . . . . . . . . . . . 13
8.2. C509 Certificate Attributes Registry . . . . . . . . . . 13
8.3. C509 Certificate Extensions Registry . . . . . . . . . . 16
8.4. C509 Certificate Extended Key Usages Registry . . . . . . 18
8.5. C509 Certificate General Names Registry . . . . . . . . . 19
8.6. C509 Certificate Signature Algorithms Registry . . . . . 20
8.7. C509 Certificate Public Key Algorithms Registry . . . . . 23
8.8. COSE Header Parameters Registry . . . . . . . . . . . . . 25
8.9. TLS Certificate Types Registry . . . . . . . . . . . . . 26
8.10. CBOR Tags Registry . . . . . . . . . . . . . . . . . . . 27
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 27
9.1. Normative References . . . . . . . . . . . . . . . . . . 27
9.2. Informative References . . . . . . . . . . . . . . . . . 28
Appendix A. Example C509 Certificates . . . . . . . . . . . . . 30
A.1. Example RFC 7925 profiled X.509 Certificate . . . . . . . 30
A.2. Example IEEE 802.1AR profiled X.509 Certificate . . . . . 34
A.3. Example CAB Baseline ECDSA HTTPS X.509 Certificate . . . 34
A.4. Example CAB Baseline RSA HTTPS X.509 Certificate . . . . 36
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 40
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 40
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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 [I-D.ietf-emu-eap-tls13] [I-D.ietf-emu-eaptlscert] where
authenticators typically drop an EAP session after only 40 - 50
round-trips and QUIC [I-D.ietf-quic-transport] where the latency
increases significantly unless the server only send less than three
times as many bytes as received prior to validating the client
address. 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
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.
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. [RFC8610] 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].
CAB Baseline Requirements [CAB-Baseline], 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 [I-D.ietf-quic-transport], DTLS
[I-D.ietf-tls-dtls13], COSE [RFC8152], EDHOC [I-D.ietf-lake-edhoc],
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
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[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 [RFC5280]. The encoding support all
[RFC7925] and IEEE 802.1AR [IEEE-802.1AR] and CAB Baseline
[CAB-Baseline] profiled X.509 certificates. The resulting
certificates are called C509 Certificates. Two variants are defined
using the same CBOR encoding and differing only in what is being
signed:
1. An invertible CBOR re-encoding of DER encoded X.509 certificates
[RFC5280], which can be reversed to obtain the original DER
encoded X.509 certificate.
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 specifies COSE headers for use of the C509 certificates
with COSE, see Section 8.8. The document also specifies a TLS
certificate type for use of the C509 certificates with TLS and QUIC
(with or without additional TLS certificate compression), see
Section 8.9.
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 [RFC5280],
[RFC7228], [RFC8610], and [RFC8949].
3. CBOR Encoding
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], and CAB Baseline [CAB-Baseline]. In the
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CBOR encoding, static fields are elided, elliptic curve points and
time values are compressed, OID are replaced with short integers, and
redundant encoding is removed. Combining these different components
reduces the certificate size significantly, which is not possible
with general purpose compressions algorithms, see Figure 2.
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 listed below, and used
in the definition of C509 certificates, see Figure 1.
C509 certificates are defined in terms of DER encoded [RFC5280] X.509
certificates:
o version. The 'version' field is encoded in the
'cborCertificateType' CBOR int. The field 'cborCertificateType'
also indicates the type of the C509 certificate. Currently, the
type can be a natively signed C509 certificate following X.509 v3
(cborCertificateType = 0) or a CBOR re-encoded X.509 v3 DER
certificate (cborCertificateType = 1), see Section 8.1.
o 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.
o signature. The 'signature' field is always the same as the
'signatureAlgorithm' field and therefore omitted from the CBOR
encoding.
o issuer. In the general case, the sequence of
'RelativeDistinguishedName' is encoded as a CBOR array of CBOR
arrays of Attributes. Typically each RelativeDistinguishedName
only contains a single attribute and the sequence is then ecoded
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as a CBOR array of Attributes. Each Attribute is encoded as a
(CBOR int, CBOR text string) pair or as a (unwrapped CBOR OID,
CBOR bytes) pair. The absolute value of the CBOR int (see
Figure 4) encodes the attribute type and the sign is used to
represent the character string type; positive for Utf8String,
negative for PrintableString. In natively signed C509
certificates all text strings are UTF-8 encoded and all attributes
SHALL have a positive sign. 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. 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 a CBOR text string. If the text
string contains an EUI-64 of the form "HH-HH-HH-HH-HH-HH-HH-HH"
where 'H' is one of the symbol '0'-'9' or 'A'-'F' it is encoded as
a CBOR byte string of length 8 instead. EUI-64 mapped from a
48-bit MAC address (i.e. of the form "HH-HH-HH-FF-FE-HH-HH-HH) is
encoded as a CBOR byte string of length 6.
o 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.
o subject. The 'subject' is encoded exactly like issuer.
o subjectPublicKeyInfo. The 'AlgorithmIdentifier' field including
parameters is encoded as the CBOR int 'subjectPublicKeyAlgorithm'
(see Section 8.7) or as an array with an unwrapped CBOR OID tag
[I-D.ietf-cbor-tags-oid] 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.
o issuerUniqueID. Not supported.
o subjectUniqueID. Not supported.
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o extensions. The 'extensions' field is encoded as a CBOR array
where each extension is encoded as either a CBOR int (see
Section 8.3) followed by an optional CBOR item of any type or an
unwrapped CBOR OID tag [I-D.ietf-cbor-tags-oid] followed by a 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, 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.
o signatureAlgorithm. The 'signatureAlgorithm' field including
parameters is encoded as a CBOR int (see Section 8.6) or as an
array with an unwrapped CBOR OID tag [I-D.ietf-cbor-tags-oid]
optionally followed by the parameters encoded as a CBOR byte
string.
o 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
The following Concise Data Definition Language (CDDL) defines
CBORCertificate and TBSCertificate, which are encoded as CBOR
Sequences [RFC8742]. The member names therefore only have
documentary value.
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; The elements of the following group are to be used in a CBOR Sequence:
CBORCertificate = (
TBSCertificate,
issuerSignatureValue : any,
)
TBSCertificate = (
cborCertificateType: int,
certificateSerialNumber: CertificateSerialNumber,
issuer: Name,
validityNotBefore: Time,
validityNotAfter: Time,
subject: Name,
subjectPublicKeyAlgorithm: AlgorithmIdentifier,
subjectPublicKey: any,
extensions: Extensions,
issuerSignatureAlgorithm: AlgorithmIdentifier,
)
CertificateSerialNumber = ~biguint
Name = [ * RelativeDistinguishedName ] / text / bytes
RelativeDistinguishedName = Attribute / [ 2* Attribute ]
Attribute = ( attributeType: int, attributeValue: text ) //
( attributeType: ~oid, attributeValue: bytes )
Time = ~time / null
AlgorithmIdentifier = int / [ algorithm: ~oid, ? parameters: bytes ]
Extensions = [ * Extension ] / int
Extension = ( extensionID: int, extensionValue: any ) //
( extensionID: ~oid, critical: bool, extensionValue: bytes )
Figure 1: CDDL for CBORCertificate.
3.2. Encoding of subjectPublicKey and issuerSingatureValue
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 :
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~biguint ]. If the exponent is 65537, the array and the exponent is
omitted and subjectPublicKey consist of only the modulus encoded as
an unwrapped CBOR unsigned bignum (~biguint).
For elliptic curve public keys in Weirstrass form (id-ecPublicKey),
uncompressed keys are point compressed as defined in Section 2.3.3 of
[SECG]. If a DER encoded certificate with a point compressed public
key of type id-ecPublicKey is CBOR encoded, 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 issuerSingatureValue
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 shortest 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
This section details the encoding of the 'extensions' field. The
'extensions' field is encoded as a CBOR array where each extensionID
is encoded as either a CBOR int or a CBOR OID tag. If 'extensionID'
is encoded an int (see Section 8.3),the sign is used to encode if the
extension is critical and the 'critical' field is omitted. Critical
extensions are encoded with a positive sign and non-critical
extensions are encoded with a negative sign.
The 'extnValue' OCTET STREAM value field is encoded as the CBOR byte
string 'extensionValue' except for the extensions specified below.
The 'extensionValue' for the extensions mandated to be supported by
[RFC7925], [IEEE-802.1AR], and [CAB-Baseline] are encoded as follows:
o keyUsage. The 'KeyUsage' BIT STRING is interpreted as an unsigned
integer n in network byte order and encoded as a CBOR int.
o subjectAltName. extensionValue is encoded as an array of (int,
any) pairs where each pair encodes a general name (see
Section 8.5). 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 identify the pair ( hwType, hwSerialEntries ) directly
as specified in [RFC4108].
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GeneralNames = [ + GeneralName ] / text
GeneralName = ( GeneralNameType : int, GeneralNameValue : any )
o 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.
o extKeyUsage. extensionValue is encoded as an array of CBOR ints
(see Section 8.4) or unwrapped CBOR OID tags
[I-D.ietf-cbor-tags-oid] where each int or OID tag encodes a key
usage purpose. If the array contains a single int, the array is
omitted.
ExtValueEKU = [ + int / ~oid ] / int
o subjectKeyIdentifier. extensionValue is the value of the
'keyIdentifier' field encoded as a CBOR byte string.
o authorityKeyIdentifier. extensionValue is encoded as an array
where the value of the 'keyIdentifier' is encoded as a CBOR byte
string, 'GeneralNames' is encoded like in subjectAltName, and
'AuthorityCertSerialNumber' is encoded as ~biguint exactly like
certificateSerialNumber. Omitted values are encoded as CBOR null.
ExtValueAKI = [ keyIdentifier: bytes / null,
certIssuer: GeneralNames / null,
certSerialNumber: CertificateSerialNumber / null ]
/ bytes
o cRLDistributionPoints. If the cRLDistributionPoints is a sequence
of DistributionPointName, it is encoded like subjectAltName, with
the difference that if cRLDistributionPoints contains exactly one
uniformResourceIdentifier, the array and the int are omitted and
extensionValue is the uniformResourceIdentifier encoded as a CBOR
text string.
o authorityInfoAccess. If authorityInfoAccess consist of only
uniformResourceIdentifiers it is encoded as an array of uris.
ExtValueAIA = [ + ( ocsp : 1 // caIssuers : 2 , uri : text ) ]
3.3.1. Example Encoding of Extensions
The examples below use values from Section 8.3, Section 8.4, and
Section 8.5:
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o A critical basicConstraints ('cA' = true) without
pathLenConstraint is encoded as the two CBOR ints -1, -1.
o A non-critical keyUsage with digitalSignature and keyAgreement
asserted is encoded as the two CBOR ints 2, 17 (2^0 + 2^4 = 17).
o A non-critical extKeyUsage containing id-kp-codeSigning and id-kp-
OCSPSigning is encoded as the CBOR int 3 followed by the CBOR
array [ 3, 6 ].
o A non-critical subjectAltName containing only the dNSName
example.com is encoded as the CBOR int 4 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 [ -1, -1, 2, 17, 3, [ 3, 6 ], 4, "example.com" ].
4. Compliance Requirements for Constrained IoT
For general purpose applications, the normative requirements of
[RFC5280] applies. This section describes the mandatory to implement
algorithms and OIDs for constrained IoT application; the values of
the OIDs including certificate fields and extensions, time format,
attributes in distinguished names, etc.
TODO: Write this section
5. Legacy Considerations
C509 certificates can be deployed with legacy X.509 certificates and
CA infrastructure. In order to verify the signature, the C509
certificate is used to recreate the original X.509 data structure to
be able 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
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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.
6. Expected Certificate Sizes
The CBOR encoding of the sample certificate given in Appendix A
results in the numbers shown in Figure 2. After [RFC7925] profiling,
most duplicated information has been removed, and the remaining text
strings are minimal in size. Therefore, the further size reduction
reached with general compression mechanisms will be small, mainly
corresponding to making the ASN.1 encoding more compact. For Brtoli
[RFC7932], the brotli command line tool 1.09 was used with the
default best compression level.
+------------------+--------------+------------+--------------------+
| | RFC 7925 | Brotli | C509 Certificate |
+------------------+---------------------------+--------------------+
| Certificate Size | 314 | 303 | 138 |
+------------------+--------------+------------+--------------------+
Figure 2: Comparing Sizes of Certificates (bytes)
7. 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 5 requires unencrypted certificates and
is not recommended.
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8. IANA Considerations
This document creates several new registries under the new heading
"C509 Certificate". 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 remaning values in the interval [-65536, 65535]
have 3 byte encodings.
8.1. C509 Certificate Types Registry
IANA has created a new registry titled "C509 Certificate Types" under
the new heading "C509 Certificate". 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 | Natively Signed C509 Certificate following X.509 v3 |
+-------+-----------------------------------------------------------+
| 1 | CBOR re-encoding of X.509 v3 Certificate |
+-------+-----------------------------------------------------------+
Figure 3: C509 Certificate Types
8.2. C509 Certificate Attributes Registry
IANA has created a new registry titled "C509 Certificate Attributes"
under the new heading "C509 Certificate". The columns of the
registry are Value, Name, OID, DER, Comments, and Reference, where
Value is an integer, and the other columns are text strings. Only
non-negative values can be registered. For values in the interval
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[0, 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 | Attribute |
+=======+===========================================================+
| 1 | Name: Common Name |
| | OID: 2.5.4.3 |
| | DER: 06 03 55 04 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 2 | Name: Surname |
| | OID: 2.5.4.4 |
| | DER: 06 03 55 04 04 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 3 | Name: Serial Number |
| | OID: 2.5.4.5 |
| | DER: 06 03 55 04 05 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 4 | Name: Country |
| | OID: 2.5.4.6 |
| | DER: 06 03 55 04 06 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 5 | Name: Locality |
| | OID: 2.5.4.7 |
| | DER: 06 03 55 04 07 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 6 | Name: State or Province |
| | OID: 2.5.4.8 |
| | DER: 06 03 55 04 08 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 7 | Name: Street Address |
| | OID: 2.5.4.9 |
| | DER: 06 03 55 04 09 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 8 | Name: Organization |
| | OID: 2.5.4.10 |
| | DER: 06 03 55 04 0A |
| | Comments: |
+-------+-----------------------------------------------------------+
| 9 | Name: Organizational Unit |
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| | OID: 2.5.4.11 |
| | DER: 06 03 55 04 0B |
| | Comments: |
+-------+-----------------------------------------------------------+
| 10 | Name: Title |
| | OID: 2.5.4.12 |
| | DER: 06 03 55 04 0C |
| | Comments: |
+-------+-----------------------------------------------------------+
| 11 | Name: Postal Code |
| | OID: 2.5.4.17 |
| | DER: 06 03 55 04 11 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 12 | Name: Given Name |
| | OID: 2.5.4.42 |
| | DER: 06 03 55 04 2A |
| | Comments: |
+-------+-----------------------------------------------------------+
| 13 | Name: Initials |
| | OID: 2.5.4.43 |
| | DER: 06 03 55 04 2B |
| | Comments: |
+-------+-----------------------------------------------------------+
| 14 | Name: Generation Qualifier |
| | OID: 2.5.4.44 |
| | DER: 06 03 55 04 2C |
| | Comments: |
+-------+-----------------------------------------------------------+
| 15 | Name: DN Qualifier |
| | OID: 2.5.4.46 |
| | DER: 06 03 55 04 2E |
| | Comments: |
+-------+-----------------------------------------------------------+
| 16 | Name: Pseudonym |
| | OID: 2.5.4.65 |
| | DER: 06 03 55 04 41 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 17 | Name: Organization Identifier |
| | OID: 2.5.4.97 |
| | DER: 06 03 55 04 61 |
| | Comments: |
+-------+-----------------------------------------------------------+
Figure 4: C509 Certificate Attributes
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8.3. C509 Certificate Extensions Registry
IANA has created a new registry titled "C509 Certificate Extensions"
under the new heading "C509 Certificate". The columns of the
registry are Value, Name, OID, DER, Comments, extensionValue, and
Reference, where Value is an integer, and the other columns are text
strings. Only non-negative values can be registered. For values in
the interval [0, 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 | Extension |
+=======+===========================================================+
| 0 | Name: Subject Key Identifier |
| | OID: 2.5.29.14 |
| | DER: 06 03 55 1D 0E |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 1 | Name: Key Usage |
| | OID: 2.5.29.15 |
| | DER: 06 03 55 1D 0F |
| | Comments: |
| | AttributeValue: int |
+-------+-----------------------------------------------------------+
| 2 | Name: Subject Alternative Name |
| | OID: 2.5.29.17 |
| | DER: 06 03 55 1D 11 |
| | Comments: |
| | extensionValue: [ + ( int, any ) ] / text |
+-------+-----------------------------------------------------------+
| 3 | Name: Basic Constraints |
| | OID: 2.5.29.19 |
| | DER: 06 03 55 1D 13 |
| | Comments: |
| | extensionValue: int |
+-------+-----------------------------------------------------------+
| 4 | Name: CRL Distribution Points |
| | OID: 2.5.29.31 |
| | DER: 06 03 55 1D 1F |
| | Comments: |
| | extensionValue: [ + ( int, any ) ] / text |
+-------+-----------------------------------------------------------+
| 5 | Name: Certificate Policies |
| | OID: 2.5.29.32 |
| | DER: 06 03 55 1D 20 |
| | Comments: |
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| | extensionValue: [ + ( oid, ? text ) ] |
+-------+-----------------------------------------------------------+
| 6 | Name: Authority Key Identifier |
| | OID: 2.5.29.35 |
| | DER: 06 03 55 1D 23 |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 7 | Name: Extended Key Usage |
| | OID: 2.5.29.37 |
| | DER: 06 03 55 1D 25 |
| | Comments: |
| | extensionValue: int |
+-------+-----------------------------------------------------------+
| 8 | Name: Authority Information Access |
| | OID: 1.3.6.1.5.5.7.1.1 |
| | DER: 06 08 2B 06 01 05 05 07 01 01 |
| | Comments: |
| | extensionValue: [ + ( 1 / 2 , text ) ] |
+-------+-----------------------------------------------------------+
| 9 | Name: Signed Certificate Timestamp List |
| | 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: [ bytes, ~biguint, |
| | AlgorithmIdentifier, bytes] |
+-------+-----------------------------------------------------------+
| 24 | Name: Subject Directory Attributes |
| | OID: 2.5.29.9 |
| | DER: 06 03 55 1D 09 |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 25 | Name: Issuer Alternative Name |
| | OID: 2.5.29.18 |
| | DER: 06 03 55 1D 12 |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 26 | Name: Name Constraints |
| | OID: 2.5.29.30 |
| | DER: 06 03 55 1D 1E |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 27 | Name: Policy Mappings |
| | OID: 2.5.29.33 |
| | DER: 06 03 55 1D 21 |
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| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 28 | Name: Policy Constraints |
| | OID: 2.5.29.36 |
| | DER: 06 03 55 1D 24 |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 29 | Name: Freshest CRL |
| | OID: 2.5.29.46 |
| | DER: 06 03 55 1D 2E |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 30 | Name: Inhibit anyPolicy |
| | OID: 2.5.29.54 |
| | DER: 06 03 55 1D 36 |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
| 31 | Name: Subject Information Access |
| | OID: 1.3.6.1.5.5.7.1.11 |
| | DER: 06 08 2B 06 01 05 05 07 01 0B |
| | Comments: |
| | extensionValue: bytes |
+-------+-----------------------------------------------------------+
Figure 5: C509 Certificate Extensions
8.4. C509 Certificate Extended Key Usages Registry
IANA has created a new registry titled "C509 Certificate Extended Key
Usages" under the new heading "C509 Certificate". The columns of the
registry are Value, Name, 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 | Extended Key Usage |
+=======+===========================================================+
| 1 | Name: TLS Server authentication |
| | OID: 1.3.6.1.5.5.7.3.1 |
| | DER: 06 08 2B 06 01 05 05 07 03 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 2 | Name: TLS Client Authentication |
| | OID: 1.3.6.1.5.5.7.3.2 |
| | DER: 06 08 2B 06 01 05 05 07 03 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 3 | Name: Code Signing |
| | OID: 1.3.6.1.5.5.7.3.3 |
| | DER: 06 08 2B 06 01 05 05 07 03 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 4 | Name: Email protection (S/MIME) |
| | OID: 1.3.6.1.5.5.7.3.4 |
| | DER: 06 08 2B 06 01 05 05 07 03 04 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 8 | Name: Time Stamping |
| | OID: 1.3.6.1.5.5.7.3.8 |
| | DER: 06 08 2B 06 01 05 05 07 03 08 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 9 | Name: OCSP Signing |
| | OID: 1.3.6.1.5.5.7.3.9 |
| | DER: 06 08 2B 06 01 05 05 07 03 09 |
| | Comments: |
+-------+-----------------------------------------------------------+
Figure 6: C509 Certificate Extended Key Usages
8.5. C509 Certificate General Names Registry
IANA has created a new registry titled "C509 Certificate General
Names" under the new heading "C509 Certificate". 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 |
+=======+===========================================================+
| -1 | Name: otherName with hardwareModuleName |
| | Comments: |
| | 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 7: C509 Certificate General Names
8.6. C509 Certificate Signature Algorithms Registry
IANA has created a new registry titled "C509 Certificate Signature
Algorithms" under the new heading "C509 Certificate". The columns of
the registry are Value, Name, 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:
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+-------+-----------------------------------------------------------+
| Value | X.509 Signature Algorithms |
+=======+===========================================================+
| -256 | Name: RSASSA-PKCS1-v1_5 with SHA-1 |
| | 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 |
| | 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 |
| | 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 |
| | 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 |
| | 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 |
| | 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 |
| | 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 |
| | OID: 1.3.101.112 |
| | Parameters: Absent |
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| | DER: 30 05 06 03 2B 65 70 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 13 | Name: Ed448 |
| | OID: 1.3.101.113 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 71 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 23 | Name: RSASSA-PKCS1-v1_5 with SHA-256 |
| | 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 |
| | 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 |
| | 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 |
| | 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 |
| | OID: 1.2.840.113549.1.1.10 |
| | Parameters: SHA-384, MGF-1 with SHA-384, saltLength = 48 |
| | DER: 30 41 06 09 2A 86 48 86 F7 0D 01 01 0A 30 34 |
| | A0 0F 30 0D 06 09 60 86 48 01 65 03 04 02 02 |
| | 05 00 A1 1C 30 1A 06 09 2A 86 48 86 F7 0D 01 |
| | 01 08 30 0D 06 09 60 86 48 01 65 03 04 02 02 |
| | 05 00 A2 03 02 01 30 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 28 | Name: RSASSA-PSS with SHA-512 |
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| | 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 |
| | 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 |
| | 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 |
| | 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 |
| | 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 |
| | 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: |
+-------+-----------------------------------------------------------+
Figure 8: C509 Certificate Signature Algorithms
8.7. C509 Certificate Public Key Algorithms Registry
IANA has created a new registry titled "C509 Certificate Public Key
Algorithms" under the new heading "C509 Certificate". The columns of
the registry are Value, Name, OID, Parameters, DER, Comments, and
Reference, where Value is an integer, and the other columns are text
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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 |
| | 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 |
| | 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 |
+-------+-----------------------------------------------------------+
| 2 | Name: EC Public Key (Weierstrass) with secp384r1 |
| | OID: 1.2.840.10045.2.1 |
| | 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 |
+-------+-----------------------------------------------------------+
| 3 | Name: EC Public Key (Weierstrass) with secp521r1 |
| | 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 |
+-------+-----------------------------------------------------------+
| 8 | Name: X25519 (Montgomery) |
| | OID: 1.3.101.110 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 6E |
| | Comments: |
+-------+-----------------------------------------------------------+
| 9 | Name: X448 (Montgomery) |
| | OID: 1.3.101.111 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 6F |
| | Comments: |
+-------+-----------------------------------------------------------+
| 10 | Name: Ed25519 (Twisted Edwards) |
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| | OID: 1.3.101.112 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 70 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 11 | Name: Ed448 (Edwards) |
| | OID: 1.3.101.113 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 71 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 16 | Name: HSS / LMS |
| | 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: |
+-------+-----------------------------------------------------------+
| 17 | Name: 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 |
| | 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: |
+-------+-----------------------------------------------------------+
Figure 9: C509 Certificate Public Key Algorithms
8.8. COSE Header Parameters Registry
EDITORS NOTE: Should x5u refer to a bag or a chain? The text should
be moved a section and not be in the IANA Section.
This document registers the following entries in the "COSE Header
Parameters" registry under the "CBOR Object Signing and Encryption
(COSE)" heading. The formatting and processing for c5b, c5c, and
c5t, and c5u are similar to x5bag, x5chain, x5t, x5u defined in
[I-D.ietf-cose-x509] except that the certificates are CBOR encoded
instead of DER encoded, uses a COSE_C5 structure instead of
COSE_X509, and that c5t MUST refer to an end-entity certificate. c5u
provides an alternative way to identify an untrusted certificate bag/
chain by reference with a URI. The content is a COSE_C5 item served
with the application/cbor content format. The COSE_C5 structure used
in c5b, c5c, and c5u is defined as:
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COSE_C5 = [ + CBORCertificate ]
As the contents of c5bag, c5chain, 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.
Note that certificates can also be identified with a 'kid' header
parameter by storing 'kid' and the associated bag or chain in a
dictionary.
+-----------+-------+----------------+------------------------------+
| Name | Label | Value Type | Description |
+===========+=======+================+==============================+
| c5b | TBD1 | COSE_C5 | An unordered bag of C509 |
| | | | certificates |
+-----------+-------+----------------+------------------------------+
| c5c | TBD2 | COSE_C5 | An ordered chain of C509 |
| | | | certificates |
+-----------+-------+----------------+------------------------------+
| c5t | TBD3 | COSE_CertHash | Hash of a C509 certificate |
+-----------+-------+----------------+------------------------------+
| c5u | TBD4 | uri | URI pointing to a COSE_C5 |
| | | | containing a ordered chain |
| | | | of certificates |
+-----------+-------+----------------+------------------------------+
8.9. 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 addtional TLS
certificate compression [RFC8879].
EDITOR'S NOTE: The TLS registrations should be discussed and approved
by the TLS WG at a later stage. When COSE WG has adopted work on
C509 certificates, it could perhaps be presented in the TLS WG. 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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8.10. 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 |
+======+============================================================+
| TDB6 | Data Item: COSE_C5 |
| | Semantics: An ordered chain of C509 certificates |
| | Reference: This document |
+------+------------------------------------------------------------+
9. References
9.1. Normative References
[I-D.ietf-cbor-tags-oid]
Bormann, C. and S. Leonard, "Concise Binary Object
Representation (CBOR) Tags for Object Identifiers", draft-
ietf-cbor-tags-oid-04 (work in progress), January 2021.
[I-D.ietf-cose-x509]
Schaad, J., "CBOR Object Signing and Encryption (COSE):
Header parameters for carrying and referencing X.509
certificates", draft-ietf-cose-x509-08 (work in progress),
December 2020.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[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/info/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/info/rfc5280>.
[RFC8152] Schaad, J., "CBOR Object Signing and Encryption (COSE)",
RFC 8152, DOI 10.17487/RFC8152, July 2017,
<https://www.rfc-editor.org/info/rfc8152>.
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[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[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/info/rfc8610>.
[RFC8742] Bormann, C., "Concise Binary Object Representation (CBOR)
Sequences", RFC 8742, DOI 10.17487/RFC8742, February 2020,
<https://www.rfc-editor.org/info/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/info/rfc8949>.
[SECG] "Elliptic Curve Cryptography, Standards for Efficient
Cryptography Group, ver. 2", 2009,
<https://secg.org/sec1-v2.pdf>.
9.2. Informative References
[CAB-Baseline]
CA/Browser Forum, ., "CA/Browser Forum, "Baseline
Requirements for the Issuance and Management of Publicly-
Trusted Certificates Version 1.7.3", October 2020,
<https://cabforum.org/baseline-requirements-documents/>.
[I-D.ietf-emu-eap-tls13]
Mattsson, J. and M. Sethi, "Using EAP-TLS with TLS 1.3",
draft-ietf-emu-eap-tls13-13 (work in progress), November
2020.
[I-D.ietf-emu-eaptlscert]
Sethi, M., Mattsson, J., and S. Turner, "Handling Large
Certificates and Long Certificate Chains in TLS-based EAP
Methods", draft-ietf-emu-eaptlscert-08 (work in progress),
November 2020.
[I-D.ietf-lake-edhoc]
Selander, G., Mattsson, J., and F. Palombini, "Ephemeral
Diffie-Hellman Over COSE (EDHOC)", draft-ietf-lake-
edhoc-03 (work in progress), December 2020.
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[I-D.ietf-quic-transport]
Iyengar, J. and M. Thomson, "QUIC: A UDP-Based Multiplexed
and Secure Transport", draft-ietf-quic-transport-34 (work
in progress), January 2021.
[I-D.ietf-tls-ctls]
Rescorla, E., Barnes, R., and H. Tschofenig, "Compact TLS
1.3", draft-ietf-tls-ctls-01 (work in progress), November
2020.
[I-D.ietf-tls-dtls13]
Rescorla, E., Tschofenig, H., and N. Modadugu, "The
Datagram Transport Layer Security (DTLS) Protocol Version
1.3", draft-ietf-tls-dtls13-40 (work in progress), January
2021.
[I-D.ietf-uta-tls13-iot-profile]
Tschofenig, H. and T. Fossati, "TLS/DTLS 1.3 Profiles for
the Internet of Things", draft-ietf-uta-tls13-iot-
profile-00 (work in progress), June 2020.
[IEEE-802.1AR]
Institute of Electrical and Electronics Engineers, .,
"IEEE Standard for Local and metropolitan area networks-
Secure Device Identity", IEEE Standard 802.1AR-2018 ,
August 2018,
<https://standards.ieee.org/standard/802_1AR-2018.html>.
[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/info/rfc7228>.
[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/info/rfc7925>.
[RFC7932] Alakuijala, J. and Z. Szabadka, "Brotli Compressed Data
Format", RFC 7932, DOI 10.17487/RFC7932, July 2016,
<https://www.rfc-editor.org/info/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/info/rfc8446>.
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[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/info/rfc8603>.
[RFC8879] Ghedini, A. and V. Vasiliev, "TLS Certificate
Compression", RFC 8879, DOI 10.17487/RFC8879, December
2020, <https://www.rfc-editor.org/info/rfc8879>.
[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
A.1. Example RFC 7925 profiled X.509 Certificate
Example of [RFC7925] profiled X.509 certificate parsed with OpenSSL.
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Certificate:
Data:
Version: 3 (0x2)
Serial Number: 128269 (0x1f50d)
Signature Algorithm: ecdsa-with-SHA256
Issuer: CN=RFC test CA
Validity
Not Before: Jan 1 00:00:00 2020 GMT
Not After : Feb 2 00:00:00 2021 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
30:44:02:20:44:5d:79:8c:90:e7:f5:00:dc:74:7a:65:4c:ec:
6c:fa:6f:03:72:76:e1:4e:52:ed:07:fc:16:29:4c:84:66:0d:
02:20:5a:33:98:5d:fb:d4:bf:dd:6d:4a:cf:38:04:c3:d4:6e:
bf:3b:7f:a6:26:40:67:4f:c0:35:4f:a0:56:db:ae:a6
The DER encoding of the above certificate is 314 bytes.
30 82 01 36 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 30 30 31 30 31 30 30 30 30 30 30
5A 17 0D 32 31 30 32 30 32 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 47 00 30 44 02 20 44 5D 79 8C 90
E7 F5 00 DC 74 7A 65 4C EC 6C FA 6F 03 72 76 E1 4E 52 ED 07 FC 16 29
4C 84 66 0D 02 20 5A 33 98 5D FB D4 BF DD 6D 4A CF 38 04 C3 D4 6E BF
3B 7F A6 26 40 67 4F C0 35 4F A0 56 DB AE A6
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A.1.1. Example C509 Certificate Encoding
The CBOR encoding of the same X.509 certificate is shown below in
CBOR diagnostic format.
/This defines a CBOR Sequence (RFC 8742):/
1,
h'01f50d',
"RFC test CA",
1577836800,
1612224000,
h'0123456789AB',
1,
h'02B1216AB96E5B3B3340F5BDF02E693F16213A04525ED44450
B1019C2DFD3838AB',
1,
0,
h'445D798C90E7F500DC747A654CEC6CFA6F037276E14E52ED07
FC16294C84660D5A33985DFBD4BFDD6D4ACF3804C3D46EBF3B
7FA62640674FC0354FA056DBAEA6
The size of the CBOR encoding (CBOR sequence) is 138 bytes.
01
43 01 F5 0D
6B 52 46 43 20 74 65 73 74 20 43 41
1A 5E 0B E1 00
1A 60 18 96 00
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
00
58 40 44 5D 79 8C 90 E7 F5 00 DC 74 7A 65 4C EC 6C FA 6F 03 72 76 E1
4E 52 ED 07 FC 16 29 4C 84 66 0D 5A 33 98 5D FB D4 BF DD 6D 4A CF 38
04 C3 D4 6E BF 3B 7F A6 26 40 67 4F C0 35 4F A0 56 DB AE A6
A.1.2. Example: Natively Signed C509 Certificate
The corresponding natively signed C509 certificate in CBOR diagnostic
format is identical, except for cborCertificateType and
signatureValue.
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/This defines a CBOR Sequence (RFC 8742):/
0,
h'01f50d',
"RFC test CA",
1577836800,
1612224000,
h'0123456789AB',
1,
h'02B1216AB96E5B3B3340F5BDF02E693F16213A04525ED44450
B1019C2DFD3838AB',
1,
6,
h'B27A0B781455F71B68290F6C2EC9A897F18FDE9B6C59575953
BC67268AB0E4DDE99D273E04E4715383AB2257C6AAA35284E5
ED18BDB91247E9F2C433136480B9'
The size of the CBOR encoding (CBOR sequence) is 138 bytes.
00
43 01 F5 0D
6B 52 46 43 20 74 65 73 74 20 43 41
1A 5E 0B E1 00
1A 60 18 96 00
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
00
58 40 B2 7A 0B 78 14 55 F7 1B 68 29 0F 6C 2E C9 A8 97 F1 8F DE 9B 6C
59 57 59 53 BC 67 26 8A B0 E4 DD E9 9D 27 3E 04 E4 71 53 83 AB 22 57
C6 AA A3 52 84 E5 ED 18 BD B9 12 47 E9 F2 C4 33 13 64 80 B9
A.1.3. Example: Additonal 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 [RFC8152]. 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.
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issuerPublicKeyAlgorithm :
1 (EC Public Key (Weierstrass) with secp256r1)
issuerPublicKey :
h'02AE4CDB01F614DEFC7121285FDC7F5C6D1D42C95647F061BA0080DF678867845E'
issuerPrivateKey :
h'DC66B3415456D649429B53223DF7532B942D6B0E0842C30BCA4C0ACF91547BB2'
subjectPrivateKey :
h'D718111F3F9BD91B92FF6877F386BDBFCEA7154268FD7F2FB56EE17D99EA16D4'
A.2. Example IEEE 802.1AR profiled X.509 Certificate
EDITOR'S NOTE: To do
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
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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
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 of the first X.509 certificate is shown below in
CBOR diagnostic format.
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/This defines a CBOR Sequence (RFC 8742):/
1,
h'047FA1E31928EE403BA0B83A395673FC',
[
-4, "IE",
-8, "Baltimore",
-9, "CyberTrust",
-1, "Baltimore CyberTrust Root"
],
1595980800,
1627560000,
[
-4, "US",
-6, "CA",
-5, "San Francisco",
-8, "Cloudflare, Inc.",
-1, "sni.cloudflaressl.com"
],
1,
h'03963ECDD84DCD1B93A1CF432D1A7217D6C63BDE3355A02F8CFB5AD8994CD44E20',
[
6, h'A5CE37EAEBB0750E946788B445FAD9241087961F',
0, h'CC0B50E7D837DBF243F3853D4860F53B39BE9B2A',
2, [2, "sni.cloudflaressl.com", 2, "www.ietf.org"],
-1, 1,
7, [1, 2],
4, ["http://crl3.digicert.com/CloudflareIncECCCA-3.crl",
"http://crl4.digicert.com/CloudflareIncECCCA-3.crl"],
5, [h'6086480186FD6C0101', "https://www.digicert.com/CPS", 2],
8, [1, "http://ocsp.digicert.com",
2, "http://cacerts.digicert.com/CloudflareIncECCCA-3.crt"],
-3, -2,
9, ...
],
0,
h'BD63CF4F7E5CFE6C29385EA71CFBFC1E3F7B1CD07251A221F77769C0F471DFEA
B5C06CC45854FA30B28288B1D3BB9A6661ED5031725B1A8202E0DA5B59F95402'
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
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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
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
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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
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 of the first X.509 certificate is shown below in
CBOR diagnostic format.
/This defines a CBOR Sequence (RFC 8742):/
1,
h'A6A55C870E39B40E',
[
-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
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3A0E314116F1B1026468A5CDF54A0ACA99963508C37E275DD0A9CFF3E728AF37
D8B67BDDF37EAE6E977FF7CA694ECCD006DF5D279B3B12E7E6FE086B527B8211
7C72B346EBC1E878B80FCBE1EBBD064458DC8350B2A0625BDC81B836E39E7C79
B2A9538AE00BC94A2A13393113BD2CCFA870CF8C8D3D01A388AE1200361D1E24
2BDD79D8530126ED284FC98694834EC8E1142E85B3AFD46EDD6946AF41250E7A
AD8BF292CA79D97B324FF777E8F9B44F235CD45C03AED8AB3ACA135F5D5D5DA1',
[
-3, -2,
7, [ 1, 2 ],
-1, 5,
4, "http://crl.starfieldtech.com/sfig2s1-242.crl",
5, [ h'6086480186fd6e01071701',
"http://certificates.starfieldtech.com/repository/", 1 ],
8, [1, "http://ocsp.starfieldtech.com/",
2, "http://certificates.starfieldtech.com/repository/sfig2.crt"],
6, h'254581685026383D3B2D2CBECD6AD9B63DB36663',
2, [ 2, "*.tools.ietf.org", 2, "tools.ietf.org" ],
0, h'AD8AB41C0751D7928907B0B784622F36557A5F4D',
9, [
h'F65C942FD1773022145418083094568EE34D131933BFDF0C2F200BCC4EF164
E3',
1715,
1,
h'8CF54852CE5635433911CF10CDB91F52B33639223AD138A41DECA6FEDE1FE9
0FBCA2254366C19A2691C47A00B5B653ABBD44C2F8BAAEF4D2DAF2527CE645
4995',
h'5CDC4392FEE6AB4544B15E9AD456E61037FBD5FA47DCA17394B25EE6F6C70E
CA',
2012,
1,
h'A5E0906E63E91D4FDDEFFF0352B91E50896007564B448A3828F596DC6B2872
6DFC91EAED02168866054EE18A2E5346C4CC51FEB3FA10A91D2EDBF99125F8
6CE6'
]
],
23,
h'14043FA0BED2EE3FA86E3A1F788EA04C35530F11061FFF60A16D0B83E9D92ADB
B33F9DB3D7E0594C19A8E419A50CA770727763D5FE64510AD27AD650A58A9238
ECCB2F0F5AC064584D5C06B9736368278B8934DC79C71D3AFD345F8314415849
80682980398A867269CC7937CEE397F7DCF39588ED81032900D2A2C7BAABD63A
8ECA090BD9FB39264BFF03D88E2D3F6B21CA8A7DD85FFB94BA83DE9CFC158D61
FA672DB0C7DB3D250A414A85D37F4946373CF4B175D052F3DDC766F14BFDAA00
EDBFE47EED01EC7BE4F646FC31FD72FE03D2F265AF4D7EE2819B7AFD303CF552
F40534A08A3E194158C8A8E05171840915AEECA57775FA18F7D577D531CCC72D'
The size of the CBOR encoding (CBOR sequence) is 1242 bytes.
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Acknowledgments
The authors want to thank Henk Birkholz, Carsten Bormann, Russ
Housley, Olle Johansson, Benjamin Kaduk, Ilari Liusvaara, Laurence
Lundblade, Thomas Peterson, Michael Richardson, Stefan Santesson, Jim
Schaad, Fraser Tweedale, and Rene Struik for reviewing and commenting
on intermediate versions of the draft.
Authors' Addresses
Shahid Raza
RISE AB
Email: shahid.raza@ri.se
Joel Hoeglund
RISE AB
Email: joel.hoglund@ri.se
Goeran Selander
Ericsson AB
Email: goran.selander@ericsson.com
John Preuss Mattsson
Ericsson AB
Email: john.mattsson@ericsson.com
Martin Furuhed
Nexus Group
Email: martin.furuhed@nexusgroup.com
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