Internet DRAFT - draft-schaad-cose-alg
draft-schaad-cose-alg
COSE Working Group J. Schaad
Internet-Draft August Cellars
Intended status: Informational March 21, 2016
Expires: September 22, 2016
CBOR Encoded Message Syntax: Additional Algorithms
draft-schaad-cose-alg-01
Abstract
This document defines the identifiers and usage for a set of
additional cryptographic algorithms in the CBOR Encoded Message
(COSE) Syntax.
The algorithms setup in this docment are: RSA-PSS, RSA-OAEP, ....
!!TBD!!
Contributing to this document
The source for this draft is being maintained in GitHub. Suggested
changes should be submitted as pull requests at <https://github.com/
cose-wg/cose-algs>. Instructions are on that page as well.
Editorial changes can be managed in GitHub, but any substantial
issues need to be discussed on the COSE mailing list.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 22, 2016.
Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Terminology . . . . . . . . . . . . . . . . 3
1.2. Document Terminology . . . . . . . . . . . . . . . . . . 3
2. Signature Algorithms . . . . . . . . . . . . . . . . . . . . 3
2.1. RSASSA-PSS . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.1. Security Considerations . . . . . . . . . . . . . . . 4
2.2. Edwards-curve Digital Signature Algorithms (EdDSA) . . . 4
3. Message Authentication (MAC) Algorithms . . . . . . . . . . . 6
4. Content Encryption Algorithms . . . . . . . . . . . . . . . . 6
5. Key Derivation Functions (KDF) . . . . . . . . . . . . . . . 6
6. Recipient Algorithms . . . . . . . . . . . . . . . . . . . . 6
6.1. RSAES-OAEP . . . . . . . . . . . . . . . . . . . . . . . 6
6.1.1. Security Considerations for RSAES-OAEP . . . . . . . 6
6.2. ECDH . . . . . . . . . . . . . . . . . . . . . . . . . . 7
7. Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
7.1. Octet Key Pair . . . . . . . . . . . . . . . . . . . . . 8
7.2. RSA Keys . . . . . . . . . . . . . . . . . . . . . . . . 9
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
8.1. COSE Header Parameter Registry . . . . . . . . . . . . . 10
8.2. COSE Header Algorithm Label Table . . . . . . . . . . . . 11
8.3. COSE Algorithm Registry . . . . . . . . . . . . . . . . . 11
8.4. COSE Key Common Parameter Registry . . . . . . . . . . . 11
8.5. COSE Key Type Parameter Registry . . . . . . . . . . . . 11
8.6. COSE Elliptic Curve Registry . . . . . . . . . . . . . . 11
9. Security Considerations . . . . . . . . . . . . . . . . . . . 12
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
10.1. Normative References . . . . . . . . . . . . . . . . . . 13
10.2. Informative References . . . . . . . . . . . . . . . . . 13
Appendix A. Document Updates . . . . . . . . . . . . . . . . . . 16
A.1. Version -00 . . . . . . . . . . . . . . . . . . . . . . . 16
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Introduction
In the process of writing RFCXXXX [I-D.ietf-cose-msg] several
algorithms were removed from that document to be addressed at a later
date. This document deals with a large set of the cryptographic
algorithms which were removed at that time.
This document provides the necessary conventions needed to use the
algorithms defined in this document. This document additionally
provides the necessary registration in the appropriate IANA registry
tables.
1.1. Requirements Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
[RFC2119].
When the words appear in lower case, their natural language meaning
is used.
1.2. Document Terminology
In this document we use the following terminology: [CREF1]
2. Signature Algorithms
This document defines two new signature algorithms: RSA-PSS and
Edwards Curve Digital Signature Algorithm (EdDSA). Both of these
signature algorithms are Signature Scheme with Appendix algorithms.
(For a discussion on the difference between signature scheme with
appendix and signature scheme with message recovery algorithms, see
[I-D.ietf-cose-msg].)
2.1. RSASSA-PSS
The RSASSA-PSS signature algorithm is defined in [RFC3447].
The RSASSA-PSS signature algorithm is parametized with a hash
function (h), a mask generation function (mgf) and a salt length
(sLen). For this specification, the mask generation function is
fixed to be MGF1 as defined in [RFC3447]. It has been recommended
that the same hash function be used for hashing the data as well as
in the mask generation function, for this specification we following
this recommendation. The salt length is the same length as the hash
function output.
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Implementations need to check that the key type is 'RSA' when
creating or verifying a signature.
The algorithms defined in this document can be found in Table 1.
+-------+-------+---------+-------------+-----------------------+
| name | value | hash | salt length | description |
+-------+-------+---------+-------------+-----------------------+
| PS256 | TBD1 | SHA-256 | 32 | RSASSA-PSS w/ SHA-256 |
| | | | | |
| PS384 | TBD2 | SHA-384 | 48 | RSASSA-PSS w/ SHA-384 |
| | | | | |
| PS512 | TBD3 | SHA-512 | 64 | RSASSA-PSS w/ SHA-512 |
+-------+-------+---------+-------------+-----------------------+
Table 1: RSASSA-PSS Algorithm Values
2.1.1. Security Considerations
In addition to needing to worry about keys that are too small to
provide the required security, there are issues with keys that are
too large. Denial of service attacks have been mounted with overly
large keys. This has the potential to consume resources with
potentially bad keys. There are two reasonable ways to address this
attack. First, a key should not be used for a cryptographic
operation until it has been matched back to an authorized user. This
approach means that no cryptography would be done except for
authorized users. Second, applications can impose maximum as well as
minimum length requirements on keys. This limits the resources
consumed even if the matching is not performed until the cryptography
has been done.
There is a theoretical hash substitution attack that can be mounted
against RSASSA-PSS. However, the requirement that the same hash
function be used consistently for all operations is an effective
mitigation against it. Unlike ECDSA, hash functions are not
truncated so that the full hash value is always signed. The internal
padding structure of RSASSA-PSS means that one needs to have multiple
collisions between the two hash functions in order to be successful
in producing a forgery based on changing the hash function. This is
highly unlikely.
2.2. Edwards-curve Digital Signature Algorithms (EdDSA)
[I-D.irtf-cfrg-eddsa] describes the elliptic curve signature scheme
Edwards-curve Digital Signature Algorithm (EdDSA). In that document,
the signature algorithm is instantiated using parameters for
edwards25519 and edwards448 curves. The document additionally
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describes two variants of the EdDSA algorithm: Pure EdDSA, where no
hash function is applied to the content before signing and, HashEdDSA
where a hash function is applied to the content before signing and
the result of that hash function is signed. For use with COSE, on
the pure EdDSA version is used. This is because it is not expected
that extremely large contents are going to be needed and, based on
the arrangement of the message structure, the entire message is going
to need to be held in memory in order to create or verify a
signature. Thus, the use of an incremental update process would not
be useful. Applications can provide the same features by defining
the content of the message as a hash value and transporting the COSE
message and the content as separate items.
The algorithms defined in this document can be found in Table 2. A
single signature algorithm is defined which can be used for multiple
curves.
+-------+-------+-------------+
| name | value | description |
+-------+-------+-------------+
| EdDSA | * | EdDSA |
+-------+-------+-------------+
Table 2: EdDSA Algorithm Values
[I-D.irtf-cfrg-eddsa] describes the method of encoding the signature
value.
When using a COSE key for this algorithm the following checks are
made:
o The 'kty' field MUST be present and it MUST be 'OKP'.
o The 'crv' field MUST be present, and it MUST be a curve defined
for this signature algorithm.
o If the 'alg' field is present, it MUST match 'EdDSA'.
o If the 'key_ops' field is present, it MUST include 'sign' when
creating an EdDSA signature.
o If the 'key_ops' field is present, it MUST include 'verify' when
verifying an EdDSA signature.
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3. Message Authentication (MAC) Algorithms
This document defines no new Message Authentication Code algorithms.
4. Content Encryption Algorithms
This document defines no new content inception algorithms.
5. Key Derivation Functions (KDF)
This document defines new new key derivation functions.
6. Recipient Algorithms
6.1. RSAES-OAEP
RSAES-OAEP is an asymmetric key encryption algorithm. The defintion
of RSAEA-OAEP can be find in Section 7.1 of [RFC3447]. The algorithm
is parameterized using a masking generation function (mgf), a hash
function (h) and encoding parameters (P). For the algorithm
identifiers defined in this section:
o mgf is always set to MFG1 from [RFC3447] and uses the same hash
function as h.
o P is always set to the empty octet string.
Table 3 summarizes the rest of the values.
+----------------------+-------+---------+-----------------------+
| name | value | hash | description |
+----------------------+-------+---------+-----------------------+
| RSAES-OAEP w/SHA-256 | -25 | SHA-256 | RSAES OAEP w/ SHA-256 |
| | | | |
| RSAES-OAEP w/SHA-512 | -26 | SHA-512 | RSAES OAEP w/ SHA-512 |
+----------------------+-------+---------+-----------------------+
Table 3: RSAES-OAEP Algorithm Values
The key type MUST be 'RSA'.
6.1.1. Security Considerations for RSAES-OAEP
A key size of 2048 bits or larger MUST be used with these algorithms.
This key size corresponds roughly to the same strength as provided by
a 128-bit symmetric encryption algorithm.
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It is highly recommended that checks on the key length be done before
starting a decryption operation. One potential denial of service
operation is to provide encrypted objects using either abnormally
long or oddly sized RSA modulus values. Implementations SHOULD be
able to encrypt and decrypt with modulus between 2048 and 16K bits in
length. Applications can impose additional restrictions on the
length of the modulus.
6.2. ECDH
The algorithm ECDH is defined for use in COSE in [I-D.ietf-cose-msg].
In this document the algorithm is extended to be used with the two
curves defined in [I-D.irtf-cfrg-curves].
The following updates [I-D.ietf-cose-msg] sections 12.4.1 and 12.5.1.
o OLD: The 'kty' field MUST be present and it MUST be 'EC2'.
o NEW: The 'kty' field MUST be present and it MUST be 'EC2' or
'OKP'.
All the rest of the checks remain the same.
7. Keys
The COSE_Key object defines a way to hold a single key object, it is
still required that the members of individual key types be defined.
This section of the document is where we define an initial set of
members for specific key types.
For each of the key types, we define both public and private members.
The public members are what is transmitted to others for their usage.
We define private members mainly for the purpose of archival of keys
by individuals. However, there are some circumstances where private
keys may be distributed by various entities in a protocol. Examples
include: Entities which have poor random number generation.
Centralized key creation for multi-cast type operations. Protocols
where a shared secret is used as a bearer token for authorization
purposes.
Key types are identified by the 'kty' member of the COSE_Key object.
In this document we define four values for the member.
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+------+--------+----------------+
| name | value | description |
+------+--------+----------------+
| OPK | TBDXX | Octet Key Pair |
| | | |
| RSA | TBDXX1 | RSA Keys |
+------+--------+----------------+
Table 4: Key Type Values
7.1. Octet Key Pair
A new key type is defined for Octet Key Pairs (OKP). Do not assume
that keys using this type are elliptic curves. This key type could
be used for other curve types (for example mathematics based on
hyper-elliptic surfaces).
The key parameters defined in this section are summarized in Table 5.
The members that are defined for this key type are:
crv contains an identifier of the curve to be used with the key.
[CREF2] The curves defined in this document for this key type can
be found in Table 6. Other curves may be registered in the future
and private curves can be used as well.
x contains the x coordinate for the EC point. The octet string
represents a little-endian encoding of x.
d contains the private key.
For public keys, it is REQUIRED that 'crv' and 'x' be present in the
structure. For private keys, it is REQUIRED that 'crv' and 'd' be
present in the structure. For private keys, it is RECOMMENDED that
'x' also be present, but it can be recomputed from the required
elements and omitting it saves on space.
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+------+-------+-------+--------+-----------------------------------+
| name | key | value | type | description |
| | type | | | |
+------+-------+-------+--------+-----------------------------------+
| crv | 1 | -1 | int / | EC Curve identifier - Taken from |
| | | | tstr | the COSE General Registry |
| | | | | |
| x | 1 | -2 | bstr | X Coordinate |
| | | | | |
| d | 1 | -4 | bstr | Private key |
+------+-------+-------+--------+-----------------------------------+
Table 5: EC Key Parameters
+------------+----------+--------+-------------+
| name | key type | value | description |
+------------+----------+--------+-------------+
| Curve25519 | EC1 | TBDYY1 | Curve 25519 |
| | | | |
| Curve448 | EC1 | TBDYY2 | Curve 448 |
+------------+----------+--------+-------------+
Table 6: EC Curves
7.2. RSA Keys
This document defines a key structure for both the public and private
halves of RSA keys. Together, an RSA public key and an RSA private
key form an RSA key pair. [CREF3]
The document also provides support for the so-called "multi-prime"
RSA where the modulus may have more than two prime factors. The
benefit of multi-prime RSA is lower computational cost for the
decryption and signature primitives. For a discussion on how multi-
prime affects the security of RSA crypto-systems, the reader is
referred to [MultiPrimeRSA].
This document follows the naming convention of [RFC3447] for the
naming of the fields of an RSA public or private key. The table
Table 7 provides a summary of the label values and the types
associated with each of those labels. The requirements for fields
for RSA keys are as follows:
o For all keys, 'kty' MUST be present and MUST have a value of 3.
o For public keys, the fields 'n' and 'e' MUST be present. All
other fields defined in Table 7 MUST be absent.
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o For private keys with two primes, the fields 'other', 'r_i', 'd_i'
and 't_i' MUST be absent, all other fields MUST be present.
o For private keys with more than two primes, all fields MUST be
present. For the third to nth primes, each of the primes is
represented as a map containing the fields 'r_i', 'd_i' and 't_i'.
The field 'other' is an array of those maps.
+-------+----------+-------+-------+--------------------------------+
| name | key type | value | type | description |
+-------+----------+-------+-------+--------------------------------+
| n | 3 | -1 | bstr | Modulus Parameter |
| | | | | |
| e | 3 | -2 | int | Exponent Parameter |
| | | | | |
| d | 3 | -3 | bstr | Private Exponent Parameter |
| | | | | |
| p | 3 | -4 | bstr | First Prime Factor |
| | | | | |
| q | 3 | -5 | bstr | Second Prime Factor |
| | | | | |
| dP | 3 | -6 | bstr | First Factor CRT Exponent |
| | | | | |
| dQ | 3 | -7 | bstr | Second Factor CRT Exponent |
| | | | | |
| qInv | 3 | -8 | bstr | First CRT Coefficient |
| | | | | |
| other | 3 | -9 | array | Other Primes Info |
| | | | | |
| r_i | 3 | -10 | bstr | i-th factor, Prime Factor |
| | | | | |
| d_i | 3 | -11 | bstr | i-th factor, Factor CRT |
| | | | | Exponent |
| | | | | |
| t_i | 3 | -12 | bstr | i-th factor, Factor CRT |
| | | | | Coefficient |
+-------+----------+-------+-------+--------------------------------+
Table 7: RSA Key Parameters
8. IANA Considerations
8.1. COSE Header Parameter Registry
There are currently no registration requests here
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8.2. COSE Header Algorithm Label Table
TBD
8.3. COSE Algorithm Registry
TBD
8.4. COSE Key Common Parameter Registry
There are currently no registration tasks inthis section.
8.5. COSE Key Type Parameter Registry
It is requested that IANA create a new registry "COSE Key Type
Parameters".
The columns of the table are:
key type This field contains a descriptive string of a key type.
This should be a value that is in the COSE General Values table
and is placed in the 'kty' field of a COSE Key structure.
name This is a descriptive name that enables easier reference to the
item. It is not used in the encoding.
label The label is to be unique for every value of key type. The
range of values is from -256 to -1. Labels are expected to be
reused for different keys.
CBOR type This field contains the CBOR type for the field
description This field contains a brief description for the field
specification This contains a pointer to the public specification
for the field if one exists
This registry will be initially populated by the values in Table 5,
and Table 7. The specification column for all of these entries will
be this document.
8.6. COSE Elliptic Curve Registry
It is requested that IANA create a new registry "COSE Elliptic Curve
Parameters".
The columns of the table are:
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name This is a descriptive name that enables easier reference to the
item. It is not used in the encoding.
value This is the value used to identify the curve. These values
MUST be unique. The integer values from -256 to 255 are
designated as Standards Track Document Required. The the integer
values from 256 to 65535 and -65536 to -257 are designated as
Specification Required. Integer values over 65535 are designated
as first come first serve. Integer values less than -65536 are
marked as private use.
key type This designates the key type(s) that can be used with this
curve.
description This field contains a brief description of the curve.
specification This contains a pointer to the public specification
for the curve if one exists.
This registry will be initially populated by the values in Table 4.
The specification column for all of these entries will be this
document.
9. Security Considerations
There are security considerations:
1. Protect private keys
2. MAC messages with more than one recipient means one cannot figure
out who sent the message
3. Use of direct key with other recipient structures hands the key
to other recipients.
4. Use of direct ECDH direct encryption is easy for people to leak
information on if there are other recipients in the message.
5. Considerations about protected vs unprotected header fields.
6. Need to verify that: 1) the kty field of the key matches the key
and algorithm being used. 2) that the kty field needs to be
included in the trust decision as well as the other key fields.
3) that the algorithm be included in the trust decision.
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10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC7049] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049,
October 2013, <http://www.rfc-editor.org/info/rfc7049>.
10.2. Informative References
[AES-GCM] Dworkin, M., "NIST Special Publication 800-38D:
Recommendation for Block Cipher Modes of Operation:
Galois/Counter Mode (GCM) and GMAC.", Nov 2007.
[DSS] U.S. National Institute of Standards and Technology,
"Digital Signature Standard (DSS)", July 2013.
[I-D.greevenbosch-appsawg-cbor-cddl]
Vigano, C. and H. Birkholz, "CBOR data definition language
(CDDL): a notational convention to express CBOR data
structures", draft-greevenbosch-appsawg-cbor-cddl-07 (work
in progress), October 2015.
[I-D.ietf-cose-msg]
Schaad, J., "CBOR Encoded Message Syntax", draft-ietf-
cose-msg-10 (work in progress), February 2016.
[I-D.irtf-cfrg-curves]
Langley, A. and M. Hamburg, "Elliptic Curves for
Security", draft-irtf-cfrg-curves-11 (work in progress),
October 2015.
[I-D.irtf-cfrg-eddsa]
Josefsson, S. and I. Liusvaara, "Edwards-curve Digital
Signature Algorithm (EdDSA)", draft-irtf-cfrg-eddsa-05
(work in progress), March 2016.
[MAC] NiST, N., "FIPS PUB 113: Computer Data Authentication",
May 1985.
[MultiPrimeRSA]
Hinek, M. and D. Cheriton, "On the Security of Multi-prime
RSA", June 2006.
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[PVSig] Brown, D. and D. Johnson, "Formal Security Proofs for a
Signature Scheme with Partial Message Recover", February
2000.
[RFC2104] Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed-
Hashing for Message Authentication", RFC 2104,
DOI 10.17487/RFC2104, February 1997,
<http://www.rfc-editor.org/info/rfc2104>.
[RFC2633] Ramsdell, B., Ed., "S/MIME Version 3 Message
Specification", RFC 2633, DOI 10.17487/RFC2633, June 1999,
<http://www.rfc-editor.org/info/rfc2633>.
[RFC2898] Kaliski, B., "PKCS #5: Password-Based Cryptography
Specification Version 2.0", RFC 2898,
DOI 10.17487/RFC2898, September 2000,
<http://www.rfc-editor.org/info/rfc2898>.
[RFC3394] Schaad, J. and R. Housley, "Advanced Encryption Standard
(AES) Key Wrap Algorithm", RFC 3394, DOI 10.17487/RFC3394,
September 2002, <http://www.rfc-editor.org/info/rfc3394>.
[RFC3447] Jonsson, J. and B. Kaliski, "Public-Key Cryptography
Standards (PKCS) #1: RSA Cryptography Specifications
Version 2.1", RFC 3447, DOI 10.17487/RFC3447, February
2003, <http://www.rfc-editor.org/info/rfc3447>.
[RFC3610] Whiting, D., Housley, R., and N. Ferguson, "Counter with
CBC-MAC (CCM)", RFC 3610, DOI 10.17487/RFC3610, September
2003, <http://www.rfc-editor.org/info/rfc3610>.
[RFC4231] Nystrom, M., "Identifiers and Test Vectors for HMAC-SHA-
224, HMAC-SHA-256, HMAC-SHA-384, and HMAC-SHA-512",
RFC 4231, DOI 10.17487/RFC4231, December 2005,
<http://www.rfc-editor.org/info/rfc4231>.
[RFC4262] Santesson, S., "X.509 Certificate Extension for Secure/
Multipurpose Internet Mail Extensions (S/MIME)
Capabilities", RFC 4262, DOI 10.17487/RFC4262, December
2005, <http://www.rfc-editor.org/info/rfc4262>.
[RFC5480] Turner, S., Brown, D., Yiu, K., Housley, R., and T. Polk,
"Elliptic Curve Cryptography Subject Public Key
Information", RFC 5480, DOI 10.17487/RFC5480, March 2009,
<http://www.rfc-editor.org/info/rfc5480>.
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[RFC5652] Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
RFC 5652, DOI 10.17487/RFC5652, September 2009,
<http://www.rfc-editor.org/info/rfc5652>.
[RFC5751] Ramsdell, B. and S. Turner, "Secure/Multipurpose Internet
Mail Extensions (S/MIME) Version 3.2 Message
Specification", RFC 5751, DOI 10.17487/RFC5751, January
2010, <http://www.rfc-editor.org/info/rfc5751>.
[RFC5752] Turner, S. and J. Schaad, "Multiple Signatures in
Cryptographic Message Syntax (CMS)", RFC 5752,
DOI 10.17487/RFC5752, January 2010,
<http://www.rfc-editor.org/info/rfc5752>.
[RFC5869] Krawczyk, H. and P. Eronen, "HMAC-based Extract-and-Expand
Key Derivation Function (HKDF)", RFC 5869,
DOI 10.17487/RFC5869, May 2010,
<http://www.rfc-editor.org/info/rfc5869>.
[RFC5990] Randall, J., Kaliski, B., Brainard, J., and S. Turner,
"Use of the RSA-KEM Key Transport Algorithm in the
Cryptographic Message Syntax (CMS)", RFC 5990,
DOI 10.17487/RFC5990, September 2010,
<http://www.rfc-editor.org/info/rfc5990>.
[RFC6090] McGrew, D., Igoe, K., and M. Salter, "Fundamental Elliptic
Curve Cryptography Algorithms", RFC 6090,
DOI 10.17487/RFC6090, February 2011,
<http://www.rfc-editor.org/info/rfc6090>.
[RFC6151] Turner, S. and L. Chen, "Updated Security Considerations
for the MD5 Message-Digest and the HMAC-MD5 Algorithms",
RFC 6151, DOI 10.17487/RFC6151, March 2011,
<http://www.rfc-editor.org/info/rfc6151>.
[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, <http://www.rfc-editor.org/info/rfc6979>.
[RFC7159] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March
2014, <http://www.rfc-editor.org/info/rfc7159>.
[RFC7252] Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
Application Protocol (CoAP)", RFC 7252,
DOI 10.17487/RFC7252, June 2014,
<http://www.rfc-editor.org/info/rfc7252>.
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Internet-DraCBOR Encoded Message Syntax: Additional Algorith March 2016
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
2015, <http://www.rfc-editor.org/info/rfc7515>.
[RFC7516] Jones, M. and J. Hildebrand, "JSON Web Encryption (JWE)",
RFC 7516, DOI 10.17487/RFC7516, May 2015,
<http://www.rfc-editor.org/info/rfc7516>.
[RFC7517] Jones, M., "JSON Web Key (JWK)", RFC 7517,
DOI 10.17487/RFC7517, May 2015,
<http://www.rfc-editor.org/info/rfc7517>.
[RFC7518] Jones, M., "JSON Web Algorithms (JWA)", RFC 7518,
DOI 10.17487/RFC7518, May 2015,
<http://www.rfc-editor.org/info/rfc7518>.
[RFC7539] Nir, Y. and A. Langley, "ChaCha20 and Poly1305 for IETF
Protocols", RFC 7539, DOI 10.17487/RFC7539, May 2015,
<http://www.rfc-editor.org/info/rfc7539>.
[SEC1] Standards for Efficient Cryptography Group, "SEC 1:
Elliptic Curve Cryptography", May 2009.
[SP800-56A]
Barker, E., Chen, L., Roginsky, A., and M. Smid, "NIST
Special Publication 800-56A: Recommendation for Pair-Wise
Key Establishment Schemes Using Discrete Logarithm
Cryptography", May 2013.
Appendix A. Document Updates
A.1. Version -00
o TBD
Editorial Comments
[CREF1] JLS: I have not gone through the document to determine what
needs to be here yet. We mostly want to grab terms which are
used in unusual ways or are not generally understood.
[CREF2] JLS: Is is the same registry for both OKP and EC2?
[CREF3] JLS: Looking at the CBOR specification, the bstr that we are
looking in our table below should most likely be specified as
big numbers rather than as binary strings. This means that we
would use the tag 6.2 instead. From my reading of the
specification, there is no difference in the encoded size of the
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resulting output. The specification of bignum does explicitly
allow for integers encoded with leading zeros.
Author's Address
Jim Schaad
August Cellars
Email: ietf@augustcellars.com
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