draft-ietf-cose-webauthn-algorithms-01.txt   draft-ietf-cose-webauthn-algorithms-02.txt 
COSE Working Group M. Jones COSE Working Group M. Jones
Internet-Draft Microsoft Internet-Draft Microsoft
Intended status: Standards Track July 8, 2019 Intended status: Standards Track October 24, 2019
Expires: January 9, 2020 Expires: April 26, 2020
COSE and JOSE Registrations for WebAuthn Algorithms COSE and JOSE Registrations for WebAuthn Algorithms
draft-ietf-cose-webauthn-algorithms-01 draft-ietf-cose-webauthn-algorithms-02
Abstract Abstract
The W3C Web Authentication (WebAuthn) specification and the FIDO2 The W3C Web Authentication (WebAuthn) specification and the FIDO
Client to Authenticator Protocol (CTAP) specification use COSE Alliance FIDO2 Client to Authenticator Protocol (CTAP) specification
algorithm identifiers. This specification registers algorithms in use CBOR Object Signing and Encryption (COSE) algorithm identifiers.
the IANA "COSE Algorithms" registry that are used by WebAuthn and This specification registers the following algorithms in the IANA
CTAP implementations that are not already registered. Also, they are "COSE Algorithms" registry, which are used by WebAuthn and CTAP
registered in the IANA "JSON Web Signature and Encryption Algorithms" implementations: RSASSA-PKCS1-v1_5 using SHA-256, SHA-384, SHA-512,
registry, when not already registered there. and SHA-1, and ECDSA using the secp256k1 curve and SHA-256. It
registers the secp256k1 elliptic curve in the IANA "COSE Elliptic
Curves" registry. Also, for use with JSON Object Signing and
Encryption (JOSE), it registers the algorithm ECDSA using the
secp256k1 curve and SHA-256 in the IANA "JSON Web Signature and
Encryption Algorithms" registry and the secp256k1 elliptic curve in
the IANA "JSON Web Key Elliptic Curve" registry.
Status of This Memo Status of This Memo
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provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on January 9, 2020. This Internet-Draft will expire on April 26, 2020.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
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carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Notation and Conventions . . . . . . . . . . 2 1.1. Requirements Notation and Conventions . . . . . . . . . . 3
2. RSASSA-PKCS1-v1_5 Signature Algorithm . . . . . . . . . . . . 3 2. RSASSA-PKCS1-v1_5 Signature Algorithm . . . . . . . . . . . . 3
3. Using secp256k1 with JOSE and COSE . . . . . . . . . . . . . 3 3. Using secp256k1 with JOSE and COSE . . . . . . . . . . . . . 4
3.1. JOSE and COSE secp256k1 Curve Key Representations . . . . 3 3.1. JOSE and COSE secp256k1 Curve Key Representations . . . . 4
3.2. ECDSA Signature with secp256k1 Curve . . . . . . . . . . 4 3.2. ECDSA Signature with secp256k1 Curve . . . . . . . . . . 5
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 3.3. Other Uses of the secp256k1 Elliptic Curve . . . . . . . 7
4.1. COSE Algorithms Registrations . . . . . . . . . . . . . . 5 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
4.2. COSE Elliptic Curves Registrations . . . . . . . . . . . 6 4.1. COSE Algorithms Registrations . . . . . . . . . . . . . . 7
4.3. JOSE Algorithms Registrations . . . . . . . . . . . . . . 6 4.2. COSE Elliptic Curves Registrations . . . . . . . . . . . 8
4.4. JSON Web Key Elliptic Curves Registrations . . . . . . . 6 4.3. JOSE Algorithms Registrations . . . . . . . . . . . . . . 8
5. Security Considerations . . . . . . . . . . . . . . . . . . . 6 4.4. JSON Web Key Elliptic Curves Registrations . . . . . . . 8
5.1. RSA Key Size Security Considerations . . . . . . . . . . 6 5. Security Considerations . . . . . . . . . . . . . . . . . . . 9
5.2. RSASSA-PKCS1-v1_5 with SHA-2 Security Considerations . . 7 5.1. RSA Key Size Security Considerations . . . . . . . . . . 9
5.3. RSASSA-PKCS1-v1_5 with SHA-1 Security Considerations . . 7 5.2. RSASSA-PKCS1-v1_5 with SHA-2 Security Considerations . . 9
5.4. secp256k1 Security Considerations . . . . . . . . . . . . 7 5.3. RSASSA-PKCS1-v1_5 with SHA-1 Security Considerations . . 9
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 5.4. secp256k1 Security Considerations . . . . . . . . . . . . 9
6.1. Normative References . . . . . . . . . . . . . . . . . . 7 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
6.2. Informative References . . . . . . . . . . . . . . . . . 8 6.1. Normative References . . . . . . . . . . . . . . . . . . 9
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 9 6.2. Informative References . . . . . . . . . . . . . . . . . 11
Document History . . . . . . . . . . . . . . . . . . . . . . . . 9 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 12
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 10 Document History . . . . . . . . . . . . . . . . . . . . . . . . 12
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction 1. Introduction
This specification defines how to use several algorithms with COSE This specification defines how to use several algorithms with CBOR
[RFC8152] that are used by implementations of the W3C Web Object Signing and Encryption (COSE) [RFC8152] that are used by
Authentication (WebAuthn) [WebAuthn] and FIDO2 Client to implementations of the W3C Web Authentication (WebAuthn) [WebAuthn]
Authenticator Protocol (CTAP) [CTAP] specifications. These and FIDO Alliance FIDO2 Client to Authenticator Protocol (CTAP)
algorithms are registered in the IANA "COSE Algorithms" registry [CTAP] specifications. These specification registers these
[IANA.COSE.Algorithms] and also in the IANA "JSON Web Signature and algorithms in the IANA "COSE Algorithms" registry
Encryption Algorithms" registry [IANA.JOSE.Algorithms], when not [IANA.COSE.Algorithms] and registers a related elliptic curve in the
already registered there. IANA "COSE Elliptic Curves" registry [IANA.COSE.Curves]. This
specification also registers a corresponding algorithm for use with
JSON Object Signing and Encryption (JOSE) [RFC7515] in the IANA "JSON
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
Web Signature and Encryption Algorithms" registry
[IANA.JOSE.Algorithms] and registers a related elliptic curve in the
IANA "JSON Web Key Elliptic Curve" registry [IANA.JOSE.Curves].
1.1. Requirements Notation and Conventions 1.1. Requirements Notation and Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
2. RSASSA-PKCS1-v1_5 Signature Algorithm 2. RSASSA-PKCS1-v1_5 Signature Algorithm
skipping to change at page 3, line 18 skipping to change at page 4, line 5
The RSASSA-PKCS1-v1_5 signature algorithm is parameterized with a The RSASSA-PKCS1-v1_5 signature algorithm is parameterized with a
hash function (h). hash function (h).
A key of size 2048 bits or larger MUST be used with these algorithms. A key of size 2048 bits or larger MUST be used with these algorithms.
Implementations need to check that the key type is 'RSA' when Implementations need to check that the key type is 'RSA' when
creating or verifying a signature. creating or verifying a signature.
The RSASSA-PKCS1-v1_5 algorithms specified in this document are in The RSASSA-PKCS1-v1_5 algorithms specified in this document are in
the following table. the following table.
+-------+-----------------------------+---------+-------------------+ Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
| Name | Value | Hash | Description |
+-------+-----------------------------+---------+-------------------+ +-------+---------------+---------+-------------------+-------------+
| RS256 | TBD (temporary assignment | SHA-256 | RSASSA-PKCS1-v1_5 | | Name | Value | Hash | Description | Recommended |
| | -257 already in place) | | using SHA-256 | +-------+---------------+---------+-------------------+-------------+
| RS384 | TBD (temporary assignment | SHA-384 | RSASSA-PKCS1-v1_5 | | RS256 | TBD | SHA-256 | RSASSA-PKCS1-v1_5 | No |
| | -258 already in place) | | using SHA-384 | | | (temporary | | using SHA-256 | |
| RS512 | TBD (temporary assignment | SHA-512 | RSASSA-PKCS1-v1_5 | | | assignment | | | |
| | -259 already in place) | | using SHA-512 | | | -257 already | | | |
| RS1 | TBD (temporary assignment | SHA-1 | RSASSA-PKCS1-v1_5 | | | in place) | | | |
| | -65535 already in place) | | using SHA-1 | | RS384 | TBD | SHA-384 | RSASSA-PKCS1-v1_5 | No |
+-------+-----------------------------+---------+-------------------+ | | (temporary | | using SHA-384 | |
| | assignment | | | |
| | -258 already | | | |
| | in place) | | | |
| RS512 | TBD | SHA-512 | RSASSA-PKCS1-v1_5 | No |
| | (temporary | | using SHA-512 | |
| | assignment | | | |
| | -259 already | | | |
| | in place) | | | |
| RS1 | TBD | SHA-1 | RSASSA-PKCS1-v1_5 | Deprecated |
| | (temporary | | using SHA-1 | |
| | assignment | | | |
| | -65535 | | | |
| | already in | | | |
| | place) | | | |
+-------+---------------+---------+-------------------+-------------+
Table 1: RSASSA-PKCS1-v1_5 Algorithm Values Table 1: RSASSA-PKCS1-v1_5 Algorithm Values
Note that these algorithms are already present in the IANA "JSON Web
Signature and Encryption Algorithms" registry [IANA.JOSE.Algorithms],
and so these registrations are only for the IANA "COSE Algorithms"
registry [IANA.COSE.Algorithms].
3. Using secp256k1 with JOSE and COSE 3. Using secp256k1 with JOSE and COSE
This section defines algorithm encodings and representations enabling This section defines algorithm encodings and representations enabling
the Standards for Efficient Cryptography Group (SECG) elliptic curve the Standards for Efficient Cryptography Group (SECG) elliptic curve
secp256k1 [SEC2] to be used for JSON Object Signing and Encryption secp256k1 [SEC2] to be used for JOSE [RFC7515] and COSE [RFC8152]
(JOSE) [RFC7515] and CBOR Object Signing and Encryption (COSE) messages.
[RFC8152] messages.
3.1. JOSE and COSE secp256k1 Curve Key Representations 3.1. JOSE and COSE secp256k1 Curve Key Representations
The Standards for Efficient Cryptography Group (SECG) elliptic curve The Standards for Efficient Cryptography Group (SECG) elliptic curve
secp256k1 [SEC2] is represented in a JSON Web Key (JWK) [RFC7517] secp256k1 [SEC2] is represented in a JSON Web Key (JWK) [RFC7517]
using these values: using these values:
o "kty": "EC" o "kty": "EC"
o "crv": "secp256k1" o "crv": "secp256k1"
plus "x" and "y" values to represent the curve point for the key. Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
Other optional values such as "alg" MAY also be present.
plus the values needed to represent the curve point, as defined in
Section 6.2.1 of [RFC7518]. As a compressed point encoding
representation is not defined for JWK elliptic curve points, the
uncompressed point encoding defined there MUST be used. The "x" and
"y" values represented MUST both be exactly 256 bits, with any
leading zeros preserved. Other optional values such as "alg" MAY
also be present.
It is represented in a COSE_Key [RFC8152] using these values: It is represented in a COSE_Key [RFC8152] using these values:
o "kty" (1): "EC2" (2) o "kty" (1): "EC2" (2)
o "crv" (-1): "secp256k1" (TBD - requested assignment 8) o "crv" (-1): "secp256k1" (TBD - requested assignment 8)
plus "x" (-2) and "y" (-3) values to represent the curve point for plus the values needed to represent the curve point, as defined in
the key. Other optional values such as "alg" (3) MAY also be Section 13.1.1 of [RFC8152]. Either the uncompressed or compressed
present. point encoding representations defined there can be used. The "x"
value represented MUST be exactly 256 bits, with any leading zeros
preserved. If the uncompressed representation is used, the "y" value
represented MUST likewise be exactly 256 bits, with any leading zeros
preserved; if the compressed representation is used, the "y" value
MUST be a boolean value, as specified in Section 13.1.1 of [RFC8152].
Other optional values such as "alg" (3) MAY also be present.
3.2. ECDSA Signature with secp256k1 Curve 3.2. ECDSA Signature with secp256k1 Curve
The ECDSA signature algorithm is defined in [DSS]. This The ECDSA signature algorithm is defined in [DSS]. This
specification defines the use of ECDSA with the secp256k1 curve and specification defines the "ES256K" algorithm identifier, which is
the SHA-256 [DSS] cryptographic hash function. Implementations need used to specify the use of ECDSA with the secp256k1 curve and the
to check that the key type is "EC" for JOSE or "EC2" (2) for COSE SHA-256 [DSS] cryptographic hash function. Implementations need to
when creating or verifying a signature. check that the key type is "EC" for JOSE or "EC2" (2) for COSE and
that the curve of the key is secp256k1 when creating or verifying a
signature.
The ECDSA secp256k1 SHA-256 digital signature is generated as The ECDSA secp256k1 SHA-256 digital signature is generated as
follows: follows:
1. Generate a digital signature of the JWS Signing Input or the COSE 1. Generate a digital signature of the JWS Signing Input or the COSE
payload using ECDSA secp256k1 SHA-256 with the desired private Sig_structure using ECDSA secp256k1 SHA-256 with the desired
key. The output will be the pair (R, S), where R and S are private key. The output will be the pair (R, S), where R and S
256-bit unsigned integers. are 256-bit unsigned integers.
2. Turn R and S into octet sequences in big-endian order, with each 2. Turn R and S into octet sequences in big-endian order, with each
array being be 32 octets long. The octet sequence array being be 32 octets long. The octet sequence
representations MUST NOT be shortened to omit any leading zero representations MUST NOT be shortened to omit any leading zero
octets contained in the values. octets contained in the values.
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
3. Concatenate the two octet sequences in the order R and then S. 3. Concatenate the two octet sequences in the order R and then S.
(Note that many ECDSA implementations will directly produce this (Note that many ECDSA implementations will directly produce this
concatenation as their output.) concatenation as their output.)
4. The resulting 64-octet sequence is the JWS Signature or COSE 4. The resulting 64-octet sequence is the JWS Signature or COSE
signature value. signature value.
Implementations SHOULD use a deterministic algorithm to generate the
ECDSA nonce, k, such as [RFC6979]. However, in situations where
devices are vulnerable to physical attacks, deterministic ECDSA has
been shown to be susceptible to fault injection attacks [Kudelski17]
[EuroSP18]. Where this is a possibility, implementations SHOULD
implement appropriate countermeasures. Where there are specific
certification requirements (such as FIPS approval), implementors
should check whether deterministic ECDSA is an approved nonce
generation method.
The ECDSA secp256k1 SHA-256 algorithm specified in this document uses The ECDSA secp256k1 SHA-256 algorithm specified in this document uses
these identifiers: these identifiers:
+------------+------------------------+-----------------------------+ +----------+-------------------+----------------------+-------------+
| JOSE Alg | COSE Alg Value | Description | | JOSE Alg | COSE Alg Value | Description | Recommended |
| Name | | | | Name | | | |
+------------+------------------------+-----------------------------+ +----------+-------------------+----------------------+-------------+
| ES256K | TBD (requested | ECDSA using secp256k1 curve | | ES256K | TBD (requested | ECDSA using | Yes |
| | assignment -43) | and SHA-256 | | | assignment -46) | secp256k1 curve and | |
+------------+------------------------+-----------------------------+ | | | SHA-256 | |
+----------+-------------------+----------------------+-------------+
Table 2: ECDSA Algorithm Values Table 2: ECDSA Algorithm Values
Implementation of this algorithm is RECOMMENDED because of its
widespread use in decentralized systems and those that chose it over
the NIST curves.
When using a JWK or COSE_Key for this algorithm, the following checks
are made:
o The "kty" field MUST be present and it MUST be "EC" for JOSE or
"EC2" for COSE.
o The "crv" field MUST be present and it MUST represent the
"secp256k1" elliptic curve.
o If the "alg" field is present, it MUST represent the "ES256K"
algorithm.
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
o If the "key_ops" field is present, it MUST include "sign" when
creating an ECDSA signature.
o If the "key_ops" field is present, it MUST include "verify" when
verifying an ECDSA signature.
o If the JWK _use_ field is present, its value MUST be "sig".
3.3. Other Uses of the secp256k1 Elliptic Curve
This specification defines how to use the secp256k1 curve for ECDSA
signatures for both JOSE and COSE implementations. While in theory,
the curve could also be used for ECDH-ES key agreement, it is beyond
the scope of this specification to state whether this is or is not
advisable. Thus, whether to recommend its use with ECDH-ES is left
for experts to decide in future specifications.
When used for ECDSA, the secp256k1 curve MUST be used only with the
"ES256K" algorithm identifier and not any others, including not with
"ES256".
4. IANA Considerations 4. IANA Considerations
4.1. COSE Algorithms Registrations 4.1. COSE Algorithms Registrations
This section registers the following values in the IANA "COSE This section registers the following values in the IANA "COSE
Algorithms" registry [IANA.COSE.Algorithms]. Algorithms" registry [IANA.COSE.Algorithms].
o Name: RS256 o Name: RS256
o Value: TBD (temporary assignment -257 already in place) o Value: TBD (temporary assignment -257 already in place)
o Description: RSASSA-PKCS1-v1_5 using SHA-256 o Description: RSASSA-PKCS1-v1_5 using SHA-256
skipping to change at page 5, line 42 skipping to change at page 8, line 4
o Recommended: No o Recommended: No
o Name: RS512 o Name: RS512
o Value: TBD (temporary assignment -259 already in place) o Value: TBD (temporary assignment -259 already in place)
o Description: RSASSA-PKCS1-v1_5 using SHA-512 o Description: RSASSA-PKCS1-v1_5 using SHA-512
o Reference: Section 2 of this document o Reference: Section 2 of this document
o Recommended: No o Recommended: No
o Name: RS1 o Name: RS1
o Value: TBD (temporary assignment -65535 already in place) o Value: TBD (temporary assignment -65535 already in place)
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
o Description: RSASSA-PKCS1-v1_5 using SHA-1 o Description: RSASSA-PKCS1-v1_5 using SHA-1
o Reference: Section 2 of this document o Reference: Section 2 of this document
o Recommended: Deprecated o Recommended: Deprecated
o Name: ES256K o Name: ES256K
o Value: TBD (requested assignment -43) o Value: TBD (requested assignment -46)
o Description: ECDSA using secp256k1 curve and SHA-256 o Description: ECDSA using secp256k1 curve and SHA-256
o Reference: Section 3.2 of this document o Reference: Section 3.2 of this document
o Recommended: Yes o Recommended: Yes
4.2. COSE Elliptic Curves Registrations 4.2. COSE Elliptic Curves Registrations
This section registers the following value in the IANA "COSE Elliptic This section registers the following value in the IANA "COSE Elliptic
Curves" registry [IANA.COSE.Curves]. Curves" registry [IANA.COSE.Curves].
o Name: secp256k1 o Name: secp256k1
skipping to change at page 6, line 42 skipping to change at page 9, line 5
This section registers the following value in the IANA "JSON Web Key This section registers the following value in the IANA "JSON Web Key
Elliptic Curve" registry [IANA.JOSE.Curves]. Elliptic Curve" registry [IANA.JOSE.Curves].
o Curve Name: secp256k1 o Curve Name: secp256k1
o Curve Description: SECG secp256k1 curve o Curve Description: SECG secp256k1 curve
o JOSE Implementation Requirements: Optional o JOSE Implementation Requirements: Optional
o Change Controller: IESG o Change Controller: IESG
o Specification Document(s): Section 3.1 of [[ this specification ]] o Specification Document(s): Section 3.1 of [[ this specification ]]
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
5. Security Considerations 5. Security Considerations
5.1. RSA Key Size Security Considerations 5.1. RSA Key Size Security Considerations
The security considerations on key sizes for RSA algorithms from The security considerations on key sizes for RSA algorithms from
Section 6.1 of [RFC8230] also apply to the RSA algorithms in this Section 6.1 of [RFC8230] also apply to the RSA algorithms in this
specification. specification.
5.2. RSASSA-PKCS1-v1_5 with SHA-2 Security Considerations 5.2. RSASSA-PKCS1-v1_5 with SHA-2 Security Considerations
The security considerations on the use of RSASSA-PKCS1-v1_5 with The security considerations on the use of RSASSA-PKCS1-v1_5 with
SHA-2 hash functions from Section 8.3 of [RFC7518] also apply to SHA-2 hash functions from Section 8.3 of [RFC7518] also apply to
their use in this specification. For that reason, these algorithms their use in this specification. For that reason, these algorithms
are registered as being "Not Recommended". are registered as being "Not Recommended".
5.3. RSASSA-PKCS1-v1_5 with SHA-1 Security Considerations 5.3. RSASSA-PKCS1-v1_5 with SHA-1 Security Considerations
The security considerations on the use of the SHA-1 hash function The security considerations on the use of the SHA-1 hash function
from [RFC6194] apply in this specification. For that reason, the from [RFC6194] apply in this specification. For that reason, the
"RS1" algorithm is registered as "Deprecated". It MUST NOT be used "RS1" algorithm is registered as "Deprecated". Likewise, the
by COSE implementations. exponent restrictions described in Section 8.3 of [RFC7518] also
apply.
A COSE algorithm identifier for this algorithm is nonetheless being A COSE algorithm identifier for this algorithm is nonetheless being
registered because deployed TPMs continue to use it, and therefore registered because deployed TPMs continue to use it, and therefore
WebAuthn implementations need a COSE algorithm identifier for "RS1" WebAuthn implementations need a COSE algorithm identifier for "RS1"
when TPM attestations using this algorithm are being represented. when TPM attestations using this algorithm are being represented.
New COSE applications MUST NOT use this algorithm.
5.4. secp256k1 Security Considerations 5.4. secp256k1 Security Considerations
Care should be taken that a secp256k1 key is not mistaken for a P-256 Care should be taken that a secp256k1 key is not mistaken for a P-256
key, given that their representations are the same except for the [RFC7518] key, given that their representations are the same except
"crv" value. for the "crv" value.
The procedures and security considerations described in the [SEC1], The procedures and security considerations described in the [SEC1],
[SEC2], and [DSS] specifications apply to implementations of this [SEC2], and [DSS] specifications apply to implementations of this
specification. specification.
6. References 6. References
6.1. Normative References 6.1. Normative References
[DSS] National Institute of Standards and Technology (NIST), [DSS] National Institute of Standards and Technology (NIST),
"Digital Signature Standard (DSS)", FIPS PUB 186-4, July "Digital Signature Standard (DSS)", FIPS PUB 186-4, July
2013, <http://nvlpubs.nist.gov/nistpubs/FIPS/ 2013, <http://nvlpubs.nist.gov/nistpubs/FIPS/
NIST.FIPS.186-4.pdf>. NIST.FIPS.186-4.pdf>.
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC6194] Polk, T., Chen, L., Turner, S., and P. Hoffman, "Security [RFC6194] Polk, T., Chen, L., Turner, S., and P. Hoffman, "Security
Considerations for the SHA-0 and SHA-1 Message-Digest Considerations for the SHA-0 and SHA-1 Message-Digest
Algorithms", RFC 6194, DOI 10.17487/RFC6194, March 2011, Algorithms", RFC 6194, DOI 10.17487/RFC6194, March 2011,
<https://www.rfc-editor.org/info/rfc6194>. <https://www.rfc-editor.org/info/rfc6194>.
skipping to change at page 8, line 43 skipping to change at page 11, line 5
[RFC8230] Jones, M., "Using RSA Algorithms with CBOR Object Signing [RFC8230] Jones, M., "Using RSA Algorithms with CBOR Object Signing
and Encryption (COSE) Messages", RFC 8230, and Encryption (COSE) Messages", RFC 8230,
DOI 10.17487/RFC8230, September 2017, DOI 10.17487/RFC8230, September 2017,
<https://www.rfc-editor.org/info/rfc8230>. <https://www.rfc-editor.org/info/rfc8230>.
[SEC1] Standards for Efficient Cryptography Group, "SEC 1: [SEC1] Standards for Efficient Cryptography Group, "SEC 1:
Elliptic Curve Cryptography", Version 2.0, May 2009, Elliptic Curve Cryptography", Version 2.0, May 2009,
<http://www.secg.org/sec1-v2.pdf>. <http://www.secg.org/sec1-v2.pdf>.
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
[SEC2] Standards for Efficient Cryptography Group, "SEC 2: [SEC2] Standards for Efficient Cryptography Group, "SEC 2:
Recommended Elliptic Curve Domain Parameters", Recommended Elliptic Curve Domain Parameters",
Version 2.0, January 2010, Version 2.0, January 2010,
<http://www.secg.org/sec2-v2.pdf>. <http://www.secg.org/sec2-v2.pdf>.
6.2. Informative References 6.2. Informative References
[CTAP] Brand, C., Czeskis, A., Ehrensvaerd, J., Jones, M., Kumar, [CTAP] Brand, C., Czeskis, A., Ehrensvaerd, J., Jones, M., Kumar,
A., Lindemann, R., Powers, A., and J. Verrept, "Client to A., Lindemann, R., Powers, A., and J. Verrept, "Client to
Authenticator Protocol (CTAP)", FIDO Alliance Proposed Authenticator Protocol (CTAP)", FIDO Alliance Proposed
Standard, January 2019, <https://fidoalliance.org/specs/ Standard, January 2019, <https://fidoalliance.org/specs/
fido-v2.0-ps-20190130/fido-client-to-authenticator- fido-v2.0-ps-20190130/fido-client-to-authenticator-
protocol-v2.0-ps-20190130.html>. protocol-v2.0-ps-20190130.html>.
[EuroSP18]
Poddebniak, D., Somorovsky, J., Schinzel, S., Lochter, M.,
and P. Roesler, "Attacking Deterministic Signature Schemes
using Fault Attacks", IEEE European Symposium on Security
and Privacy (EuroS&P) 2018, April 2018,
<https://eprint.iacr.org/2017/1014.pdf>.
[IANA.COSE.Algorithms] [IANA.COSE.Algorithms]
IANA, "COSE Algorithms", IANA, "COSE Algorithms",
<https://www.iana.org/assignments/cose/ <https://www.iana.org/assignments/cose/
cose.xhtml#algorithms>. cose.xhtml#algorithms>.
[IANA.COSE.Curves] [IANA.COSE.Curves]
IANA, "COSE Elliptic Curves", IANA, "COSE Elliptic Curves",
<https://www.iana.org/assignments/cose/ <https://www.iana.org/assignments/cose/
cose.xhtml#elliptic-curves>. cose.xhtml#elliptic-curves>.
[IANA.JOSE.Algorithms] [IANA.JOSE.Algorithms]
IANA, "JSON Web Signature and Encryption Algorithms", IANA, "JSON Web Signature and Encryption Algorithms",
<https://www.iana.org/assignments/jose/ <https://www.iana.org/assignments/jose/jose.xhtml#web-
jose.xhtml#web-signature-encryption-algorithms>. signature-encryption-algorithms>.
[IANA.JOSE.Curves] [IANA.JOSE.Curves]
IANA, "JSON Web Key Elliptic Curve", IANA, "JSON Web Key Elliptic Curve",
<https://www.iana.org/assignments/jose/ <https://www.iana.org/assignments/jose/jose.xhtml#web-key-
jose.xhtml#web-key-elliptic-curve>. elliptic-curve>.
[Kudelski17]
Romailler, Y., "How to defeat Ed25519 and EdDSA using
faults", October 2017,
<https://research.kudelskisecurity.com/2017/10/04/
defeating-eddsa-with-faults/>.
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
[RFC6979] Pornin, T., "Deterministic Usage of the Digital Signature
Algorithm (DSA) and Elliptic Curve Digital Signature
Algorithm (ECDSA)", RFC 6979, DOI 10.17487/RFC6979, August
2013, <https://www.rfc-editor.org/info/rfc6979>.
[WebAuthn] [WebAuthn]
Balfanz, D., Czeskis, A., Hodges, J., Jones, J., Jones, Balfanz, D., Czeskis, A., Hodges, J., Jones, J., Jones,
M., Kumar, A., Liao, A., Lindemann, R., and E. Lundberg, M., Kumar, A., Liao, A., Lindemann, R., and E. Lundberg,
"Web Authentication: An API for accessing Public Key "Web Authentication: An API for accessing Public Key
Credentials - Level 1", World Wide Web Consortium Credentials - Level 1", World Wide Web Consortium
(W3C) Recommendation, March 2019, (W3C) Recommendation, March 2019,
<https://www.w3.org/TR/2019/REC-webauthn-1-20190304/>. <https://www.w3.org/TR/2019/REC-webauthn-1-20190304/>.
Acknowledgements Acknowledgements
Thanks to Stephen Farrell, John Fontana, Jeff Hodges, John Mattsson, Thanks to Stephen Farrell, John Fontana, Jeff Hodges, Kevin Jacobs,
Tony Nadalin, Matt Palmer, Jim Schaad, Goeran Selander, Wendy J.C. Jones, Benjamin Kaduk, Neil Madden, John Mattsson, Tony
Seltzer, Sean Turner, and Samuel Weiler for their roles in Nadalin, Matt Palmer, Jim Schaad, Goeran Selander, Wendy Seltzer,
registering these algorithm identifiers. Sean Turner, and Samuel Weiler for their roles in registering these
algorithm identifiers.
Document History Document History
[[ to be removed by the RFC Editor before publication as an RFC ]] [[ to be removed by the RFC Editor before publication as an RFC ]]
-02
o Addressed working group last call comments. Thanks to J.C.
Jones, Kevin Jacobs, Jim Schaad, Neil Madden, and Benjamin Kaduk
for their useful feedback.
-01 -01
o Changed the JOSE curve identifier from "P-256K" to "secp256k1". o Changed the JOSE curve identifier from "P-256K" to "secp256k1".
o Specified that secp256k1 signing is done using the SHA-256 hash o Specified that secp256k1 signing is done using the SHA-256 hash
function. function.
-00 -00
o Created the initial working group draft from draft-jones-cose- o Created the initial working group draft from draft-jones-cose-
additional-algorithms-00, changing only the title, date, and additional-algorithms-00, changing only the title, date, and
history entry. history entry.
skipping to change at page 10, line 15 skipping to change at page 13, line 5
o Specified that secp256k1 signing is done using the SHA-256 hash o Specified that secp256k1 signing is done using the SHA-256 hash
function. function.
-00 -00
o Created the initial working group draft from draft-jones-cose- o Created the initial working group draft from draft-jones-cose-
additional-algorithms-00, changing only the title, date, and additional-algorithms-00, changing only the title, date, and
history entry. history entry.
Internet-DrafCOSE and JOSE Registrations for WebAuthn Algor October 2019
Author's Address Author's Address
Michael B. Jones Michael B. Jones
Microsoft Microsoft
Email: mbj@microsoft.com Email: mbj@microsoft.com
URI: http://self-issued.info/ URI: http://self-issued.info/
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