Internet Engineering Task Force (IETF)                         S. Turner
Request for Comments: 5753                                          IECA
Obsoletes: 3278                                                 D. Brown
Category: Informational                                         Certicom
ISSN: 2070-1721                                             January 2010


         Use of Elliptic Curve Cryptography (ECC) Algorithms
                in Cryptographic Message Syntax (CMS)

Abstract

  This document describes how to use Elliptic Curve Cryptography (ECC)
  public key algorithms in the Cryptographic Message Syntax (CMS).  The
  ECC algorithms support the creation of digital signatures and the
  exchange of keys to encrypt or authenticate content.  The definition
  of the algorithm processing is based on the NIST FIPS 186-3 for
  digital signature, NIST SP800-56A and SEC1 for key agreement, RFC
  3370 and RFC 3565 for key wrap and content encryption, NIST FIPS
  180-3 for message digest, SEC1 for key derivation, and RFC 2104 and
  RFC 4231 for message authentication code standards.  This document
  obsoletes RFC 3278.

Status of This Memo

  This document is not an Internet Standards Track specification; it is
  published for informational purposes.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Not all documents
  approved by the IESG are a candidate for any level of Internet
  Standard; see Section 2 of RFC 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc5753.

Copyright Notice

  Copyright (c) 2010 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
  (http://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents



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  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.

  This document may contain material from IETF Documents or IETF
  Contributions published or made publicly available before November
  10, 2008.  The person(s) controlling the copyright in some of this
  material may not have granted the IETF Trust the right to allow
  modifications of such material outside the IETF Standards Process.
  Without obtaining an adequate license from the person(s) controlling
  the copyright in such materials, this document may not be modified
  outside the IETF Standards Process, and derivative works of it may
  not be created outside the IETF Standards Process, except to format
  it for publication as an RFC or to translate it into languages other
  than English.

Table of Contents

  1. Introduction ....................................................3
     1.1. Requirements Terminology ...................................3
  2. SignedData Using ECC ............................................3
     2.1. SignedData Using ECDSA .....................................4
  3. EnvelopedData Using ECC Algorithms ..............................5
     3.1. EnvelopedData Using (ephemeral-static) ECDH ................5
     3.2. EnvelopedData Using 1-Pass ECMQV ...........................8
  4. AuthenticatedData and AuthEnvelopedData Using ECC ..............11
     4.1. AuthenticatedData Using 1-Pass ECMQV ......................11
     4.2. AuthEnvelopedData Using 1-Pass ECMQV ......................12
  5. Certificates Using ECC .........................................13
  6. SMIMECapabilities Attribute and ECC ............................13
  7. ASN.1 Syntax ...................................................21
     7.1. Algorithm Identifiers .....................................21
     7.2. Other Syntax ..............................................24
  8. Recommended Algorithms and Elliptic Curves .....................26
  9. Security Considerations ........................................28
  10. IANA Considerations ...........................................33
  11. References ....................................................33
     11.1. Normative References .....................................33
     11.2. Informative References ...................................35
  Appendix A.  ASN.1 Modules.........................................37
     A.1.  1988 ASN.1 Module.........................................37
     A.2.  2004 ASN.1 Module.........................................45
  Appendix B. Changes since RFC 3278.................................59
  Acknowledgements...................................................61





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1.  Introduction

  The Cryptographic Message Syntax (CMS) is cryptographic algorithm
  independent.  This specification defines a profile for the use of
  Elliptic Curve Cryptography (ECC) public key algorithms in the CMS.
  The ECC algorithms are incorporated into the following CMS content
  types:

  -  'SignedData' to support ECC-based digital signature methods
     (ECDSA) to sign content;

  -  'EnvelopedData' to support ECC-based public key agreement methods
     (ECDH and ECMQV) to generate pairwise key-encryption keys to
     encrypt content-encryption keys used for content encryption;

  -  'AuthenticatedData' to support ECC-based public key agreement
     methods (ECMQV) to generate pairwise key-encryption keys to
     encrypt message-authentication keys used for content
     authentication and integrity; and

  -  'AuthEnvelopedData' to support ECC-based public key agreement
     methods (ECMQV) to generate pairwise key-encryption keys to
     encrypt message-authentication and content-encryption keys used
     for content authentication, integrity, and encryption.

  Certification of EC public keys is also described to provide public
  key distribution in support of the specified techniques.

  The document will obsolete [CMS-ECC].  The technical changes
  performed since RFC 3278 are detailed in Appendix B.

1.1.  Requirements Terminology

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
  document are to be interpreted as described in [MUST].

2.  SignedData Using ECC

  This section describes how to use ECC algorithms with the CMS
  SignedData format to sign data.










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2.1.  SignedData Using ECDSA

  This section describes how to use the Elliptic Curve Digital
  Signature Algorithm (ECDSA) with SignedData.  ECDSA is specified in
  [FIPS186-3].  The method is the elliptic curve analog of the Digital
  Signature Algorithm (DSA) [FIPS186-3].  ECDSA is used with the Secure
  Hash Algorithm (SHA) [FIPS180-3].

  In an implementation that uses ECDSA with CMS SignedData, the
  following techniques and formats MUST be used.

2.1.1.  Fields of the SignedData

  When using ECDSA with SignedData, the fields of SignerInfo are as in
  [CMS], but with the following restrictions:

  -  digestAlgorithm MUST contain the algorithm identifier of the hash
     algorithm (see Section 7.1.1), which MUST be one of the following:
     id-sha1, id-sha224, id-sha256, id-sha384, or id-sha512.

  -  signatureAlgorithm contains the signature algorithm identifier
     (see Section 7.1.3): ecdsa-with-SHA1, ecdsa-with-SHA224, ecdsa-
     with-SHA256, ecdsa-with-SHA384, or ecdsa-with-SHA512.  The hash
     algorithm identified in the name of the signature algorithm MUST
     be the same as the digestAlgorithm (e.g., digestAlgorithm is id-
     sha256 therefore signatureAlgorithm is ecdsa-with-SHA256).

  -  signature MUST contain the DER encoding (as an octet string) of a
     value of the ASN.1 type ECDSA-Sig-Value (see Section 7.2).

  When using ECDSA, the SignedData certificates field MAY include the
  certificate(s) for the EC public key(s) used in the generation of the
  ECDSA signatures in SignedData.  ECC certificates are discussed in
  Section 5.

2.1.2.  Actions of the Sending Agent

  When using ECDSA with SignedData, the sending agent uses the message
  digest calculation process and signature generation process for
  SignedData that are specified in [CMS].  To sign data, the sending
  agent uses the signature method specified in [FIPS186-3].

  The sending agent encodes the resulting signature using the ECDSA-
  Sig-Value syntax (see Section 7.2) and places it in the SignerInfo
  signature field.






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2.1.3.  Actions of the Receiving Agent

  When using ECDSA with SignedData, the receiving agent uses the
  message digest calculation process and signature verification process
  for SignedData that are specified in [CMS].  To verify SignedData,
  the receiving agent uses the signature verification method specified
  in [FIPS186-3].

  In order to verify the signature, the receiving agent retrieves the
  integers r and s from the SignerInfo signature field of the received
  message.

3.  EnvelopedData Using ECC Algorithms

  This section describes how to use ECC algorithms with the CMS
  EnvelopedData format.

  This document does not specify the static-static ECDH, method C(0,2,
  ECC CDH) from [SP800-56A].  Static-static ECDH is analogous to
  static-static DH, which is specified in [CMS-ALG].  Ephemeral-static
  ECDH and 1-Pass ECMQV were specified because they provide better
  security due to the originator's ephemeral contribution to the key
  agreement scheme.

3.1.  EnvelopedData Using (ephemeral-static) ECDH

  This section describes how to use the ephemeral-static Elliptic Curve
  Diffie-Hellman (ECDH) key agreement algorithm with EnvelopedData.
  This algorithm has two variations:

  - 'Standard' ECDH, described as the 'Elliptic Curve Diffie-Hellman
    Scheme' with the 'Elliptic Curve Diffie-Hellman Primitive' in
    [SEC1], and

  - 'Co-factor' ECDH, described as the 'One-Pass Diffie-Hellman scheme'
    (method C(1, 1, ECC CDH)) in [SP800-56A].

  Both variations of ephemeral-static ECDH are elliptic curve analogs
  of the ephemeral-static Diffie-Hellman key agreement algorithm
  specified jointly in the documents [CMS-ALG] and [CMS-DH].

  If an implementation uses ECDH with CMS EnvelopedData, then the
  following techniques and formats MUST be used.

  The fields of EnvelopedData are as in [CMS]; as ECDH is a key
  agreement algorithm, the RecipientInfo kari choice is used.





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3.1.1.  Fields of KeyAgreeRecipientInfo

  When using ephemeral-static ECDH with EnvelopedData, the fields of
  KeyAgreeRecipientInfo are as follows:

  -  version MUST be 3.

  -  originator MUST be the alternative originatorKey.  The
     originatorKey algorithm field MUST contain the id-ecPublicKey
     object identifier (see Section 7.1.2).  The parameters associated
     with id-ecPublicKey MUST be absent, ECParameters, or NULL.  The
     parameters associated with id-ecPublicKey SHOULD be absent or
     ECParameters, and NULL is allowed to support legacy
     implementations.  The previous version of this document required
     NULL to be present.  If the parameters are ECParameters, then they
     MUST be namedCurve.  The originatorKey publicKey field MUST
     contain the DER encoding of the value of the ASN.1 type ECPoint
     (see Section 7.2), which represents the sending agent's ephemeral
     EC public key.  The ECPoint in uncompressed form MUST be
     supported.

  -  ukm MAY be present or absent.  However, message originators SHOULD
     include the ukm.  As specified in RFC 3852 [CMS], implementations
     MUST support ukm message recipient processing, so interoperability
     is not a concern if the ukm is present or absent.  The ukm is
     placed in the entityUInfo field of the ECC-CMS-SharedInfo
     structure.  When present, the ukm is used to ensure that a
     different key-encryption key is generated, even when the ephemeral
     private key is improperly used more than once, by using the ECC-
     CMS-SharedInfo as an input to the key derivation function (see
     Section 7.2).

  -  keyEncryptionAlgorithm MUST contain the object identifier of the
     key-encryption algorithm, which in this case is a key agreement
     algorithm (see Section 7.1.4).  The parameters field contains
     KeyWrapAlgorithm.  The KeyWrapAlgorithm is the algorithm
     identifier that indicates the symmetric encryption algorithm used
     to encrypt the content-encryption key (CEK) with the key-
     encryption key (KEK) and any associated parameters (see Section
     7.1.5).  Algorithm requirements are found in Section 8.

  -  recipientEncryptedKeys contains an identifier and an encrypted key
     for each recipient.  The RecipientEncryptedKey
     KeyAgreeRecipientIdentifier MUST contain either the
     issuerAndSerialNumber identifying the recipient's certificate or
     the RecipientKeyIdentifier containing the subject key identifier
     from the recipient's certificate.  In both cases, the recipient's
     certificate contains the recipient's static ECDH public key.



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     RecipientEncryptedKey EncryptedKey MUST contain the content-
     encryption key encrypted with the ephemeral-static, ECDH-generated
     pairwise key-encryption key using the algorithm specified by the
     KeyWrapAlgorithm.

3.1.2.  Actions of the Sending Agent

  When using ephemeral-static ECDH with EnvelopedData, the sending
  agent first obtains the recipient's EC public key and domain
  parameters (e.g., from the recipient's certificate).  The sending
  agent then performs one of the two ECDH variations mentioned above:

  - If the value of keyEncryptionAlgorithm indicates the use of
    'standard' Diffie-Hellman, then the sending agent performs the
    'Elliptic Curve Diffie-Hellman Scheme' with the 'Elliptic Curve
    Diffie-Hellman Primitive' in [SEC1].

  - If the value of keyEncryptionAlgorithm indicates the use of 'co-
    factor' Diffie-Hellman, then the sending agent performs the 'One-
    Pass Diffie-Hellman scheme' (method C(1, 1, ECC CDH)) in
    [SP800-56A].

  In both of these cases, the sending agent uses the KDF defined in
  Section 3.6.1 of [SEC1] with the hash algorithm identified by the
  value of keyEncryptionAlgorithm.  As a result, the sending agent
  obtains:

  -  an ephemeral public key, which is represented as a value of the
     type ECPoint (see Section 7.2), encapsulated in a bit string and
     placed in the KeyAgreeRecipientInfo originator originatorKey
     publicKey field, and

  -  a shared secret bit string "K", which is used as the pairwise key-
     encryption key for that recipient, as specified in [CMS].

  In a single message, if there are multiple layers for a recipient,
  then the ephemeral public key can be reused by the originator for
  that recipient in each of the different layers.

3.1.3.  Actions of the Receiving Agent

  When using ephemeral-static ECDH with EnvelopedData, the receiving
  agent determines the bit string "SharedInfo", which is the DER
  encoding of ECC-CMS-SharedInfo (see Section 7.2), and the integer
  "keydatalen" from the key size, in bits, of the KeyWrapAlgorithm.
  The receiving agent retrieves the ephemeral EC public key from the
  bit string KeyAgreeRecipientInfo originator, with a value of the type
  ECPoint (see Section 7.2) encapsulated as a bit string, and if



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  present, originally supplied additional user key material from the
  ukm field.  The receiving agent then performs one of the two ECDH
  variations mentioned above:

  - If the value of keyEncryptionAlgorithm indicates the use of
    'standard' Diffie-Hellman, then the receiving agent performs the
    'Elliptic Curve Diffie-Hellman Scheme' with the 'Elliptic Curve
    Diffie-Hellman Primitive' in [SEC1].

  - If the value of keyEncryptionAlgorithm indicates the use of 'co-
    factor' Diffie-Hellman, then the receiving agent performs the 'One-
    Pass Diffie-Hellman scheme' (method C(1, 1, ECC CDH)) in
    [SP800-56A].

  In both of these cases, the receiving agent uses the KDF defined in
  Section 3.6.1 of [SEC1] with the hash algorithm identified by the
  value of keyEncryptionAlgorithm.  As a result, the receiving agent
  obtains a shared secret bit string "K", which is used as the pairwise
  key-encryption key to unwrap the CEK.

3.2.  EnvelopedData Using 1-Pass ECMQV

  This section describes how to use the 1-Pass Elliptic Curve Menezes-
  Qu-Vanstone (ECMQV) key agreement algorithm with EnvelopedData,
  method C(1, 2, ECC MQV) from [SP800-56A].  Like the KEA algorithm
  [CMS-KEA], 1-Pass ECMQV uses three key pairs: an ephemeral key pair,
  a static key pair of the sending agent, and a static key pair of the
  receiving agent.  Using an algorithm with the sender static key pair
  allows for knowledge of the message creator; this means that
  authentication can, in some circumstances, be obtained for
  AuthEnvelopedData and AuthenticatedData.  This means that 1-Pass
  ECMQV can be a common algorithm for EnvelopedData, AuthenticatedData,
  and AuthEnvelopedData, while ECDH can only be used in EnvelopedData.

  If an implementation uses 1-Pass ECMQV with CMS EnvelopedData, then
  the following techniques and formats MUST be used.

  The fields of EnvelopedData are as in [CMS]; as 1-Pass ECMQV is a key
  agreement algorithm, the RecipientInfo kari choice is used.  When
  using 1-Pass ECMQV, the EnvelopedData originatorInfo field MAY
  include the certificate(s) for the EC public key(s) used in the
  formation of the pairwise key.  ECC certificates are discussed in
  Section 5.








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3.2.1.  Fields of KeyAgreeRecipientInfo

  When using 1-Pass ECMQV with EnvelopedData, the fields of
  KeyAgreeRecipientInfo are as follows:

  -  version MUST be 3.

  -  originator identifies the static EC public key of the sender.  It
     SHOULD be one of the alternatives, issuerAndSerialNumber or
     subjectKeyIdentifier, and point to one of the sending agent's
     certificates.

  -  ukm MUST be present.  The ukm field is an octet string that MUST
     contain the DER encoding of the type MQVuserKeyingMaterial (see
     Section 7.2).  The MQVuserKeyingMaterial ephemeralPublicKey
     algorithm field MUST contain the id-ecPublicKey object identifier
     (see Section 7.1.2).  The parameters associated with id-
     ecPublicKey MUST be absent, ECParameters, or NULL.  The parameters
     associated with id-ecPublicKey SHOULD be absent or ECParameters,
     as NULL is allowed to support legacy implementations.  The
     previous version of this document required NULL to be present.  If
     the parameters are ECParameters, then they MUST be namedCurve.
     The MQVuserKeyingMaterial ephemeralPublicKey publicKey field MUST
     contain the DER encoding of the ASN.1 type ECPoint (see Section
     7.2) representing the sending agent's ephemeral EC public key.
     The MQVuserKeyingMaterial addedukm field, if present, contains
     additional user keying material from the sending agent.

  -  keyEncryptionAlgorithm MUST contain the object identifier of the
     key-encryption algorithm, which in this case is a key agreement
     algorithm (see Section 7.1.4).  The parameters field contains
     KeyWrapAlgorithm.  The KeyWrapAlgorithm indicates the symmetric
     encryption algorithm used to encrypt the CEK with the KEK
     generated using the 1-Pass ECMQV algorithm and any associated
     parameters (see Section 7.1.5).  Algorithm requirements are found
     in Section 8.

  -  recipientEncryptedKeys contains an identifier and an encrypted key
     for each recipient.  The RecipientEncryptedKey
     KeyAgreeRecipientIdentifier MUST contain either the
     issuerAndSerialNumber identifying the recipient's certificate or
     the RecipientKeyIdentifier containing the subject key identifier
     from the recipient's certificate.  In both cases, the recipient's
     certificate contains the recipient's static ECMQV public key.
     RecipientEncryptedKey EncryptedKey MUST contain the content-
     encryption key encrypted with the 1-Pass ECMQV-generated pairwise
     key-encryption key using the algorithm specified by the
     KeyWrapAlgorithm.



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3.2.2.  Actions of the Sending Agent

  When using 1-Pass ECMQV with EnvelopedData, the sending agent first
  obtains the recipient's EC public key and domain parameters (e.g.,
  from the recipient's certificate), and checks that the domain
  parameters are the same as the sender's domain parameters.  The
  sending agent then determines an integer "keydatalen", which is the
  KeyWrapAlgorithm symmetric key size in bits, and also a bit string
  "SharedInfo", which is the DER encoding of ECC-CMS-SharedInfo (see
  Section 7.2).  The sending agent then performs the key deployment and
  key agreement operations of the Elliptic Curve MQV Scheme specified
  in [SP800-56A], but uses the KDF defined in Section 3.6.1 of [SEC1].
  As a result, the sending agent obtains:

  - an ephemeral public key, which is represented as a value of type
    ECPoint (see Section 7.2), encapsulated in a bit string, placed in
    an MQVuserKeyingMaterial ephemeralPublicKey publicKey field (see
    Section 7.2), and

  - a shared secret bit string "K", which is used as the pairwise key-
    encryption key for that recipient, as specified in [CMS].

  In a single message, if there are multiple layers for a recipient,
  then the ephemeral public key can be reused by the originator for
  that recipient in each of the different layers.

3.2.3.  Actions of the Receiving Agent

  When using 1-Pass ECMQV with EnvelopedData, the receiving agent
  determines the bit string "SharedInfo", which is the DER encoding of
  ECC-CMS-SharedInfo (see Section 7.2), and the integer "keydatalen"
  from the key size, in bits, of the KeyWrapAlgorithm.  The receiving
  agent then retrieves the static and ephemeral EC public keys of the
  originator, from the originator and ukm fields as described in
  Section 3.2.1, and its static EC public key identified in the rid
  field and checks that the originator's domain parameters are the same
  as the recipient's domain parameters.  The receiving agent then
  performs the key agreement operation of the Elliptic Curve MQV Scheme
  [SP800-56A], but uses the KDF defined in Section 3.6.1 of [SEC1].  As
  a result, the receiving agent obtains a shared secret bit string "K",
  which is used as the pairwise key-encryption key to unwrap the CEK.










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4.  AuthenticatedData and AuthEnvelopedData Using ECC

  This section describes how to use ECC algorithms with the CMS
  AuthenticatedData format.  AuthenticatedData lacks non-repudiation,
  and so in some instances is preferable to SignedData.  (For example,
  the sending agent might not want the message to be authenticated when
  forwarded.)

  This section also describes how to use ECC algorithms with the CMS
  AuthEnvelopedData format [CMS-AUTHENV].  AuthEnvelopedData supports
  authentication and encryption, and in some instances is preferable to
  signing and then encrypting data.

  For both AuthenticatedData and AuthEnvelopedData, data origin
  authentication with 1-Pass ECMQV can only be provided when there is
  one and only one recipient.  When there are multiple recipients, an
  attack is possible where one recipient modifies the content without
  other recipients noticing [BON].  A sending agent who is concerned
  with such an attack SHOULD use a separate AuthenticatedData or
  AuthEnvelopedData for each recipient.

  Using an algorithm with the sender static key pair allows for
  knowledge of the message creator; this means that authentication can,
  in some circumstances, be obtained for AuthEnvelopedData and
  AuthenticatedData.  This means that 1-Pass ECMQV can be a common
  algorithm for EnvelopedData, AuthenticatedData, and AuthEnvelopedData
  while ECDH can only be used in EnvelopedData.

4.1.  AuthenticatedData Using 1-Pass ECMQV

  This section describes how to use the 1-Pass ECMQV key agreement
  algorithm with AuthenticatedData.  ECMQV is method C(1, 2, ECC MQV)
  from [SP800-56A].

  When using ECMQV with AuthenticatedData, the fields of
  AuthenticatedData are as in [CMS], but with the following
  restrictions:

  - macAlgorithm MUST contain the algorithm identifier of the message
    authentication code (MAC) algorithm (see Section 7.1.7), which MUST
    be one of the following: hmac-SHA1, id-hmacWITHSHA224, id-
    hmacWITHSHA256, id-hmacWITHSHA384, or id-hmacWITHSHA512.

  - digestAlgorithm MUST contain the algorithm identifier of the hash
    algorithm (see Section 7.1.1), which MUST be one of the following:
    id-sha1, id-sha224, id-sha256, id-sha384, or id-sha512.





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  As 1-Pass ECMQV is a key agreement algorithm, the RecipientInfo kari
  choice is used in the AuthenticatedData.  When using 1-Pass ECMQV,
  the AuthenticatedData originatorInfo field MAY include the
  certificate(s) for the EC public key(s) used in the formation of the
  pairwise key.  ECC certificates are discussed in Section 5.

4.1.1.  Fields of the KeyAgreeRecipientInfo

  The AuthenticatedData KeyAgreeRecipientInfo fields are used in the
  same manner as the fields for the corresponding EnvelopedData
  KeyAgreeRecipientInfo fields of Section 3.2.1 of this document.

4.1.2.  Actions of the Sending Agent

  The sending agent uses the same actions as for EnvelopedData with
  1-Pass ECMQV, as specified in Section 3.2.2 of this document.

  In a single message, if there are multiple layers for a recipient,
  then the ephemeral public key can be reused by the originator for
  that recipient in each of the different layers.

4.1.3.  Actions of the Receiving Agent

  The receiving agent uses the same actions as for EnvelopedData with
  1-Pass ECMQV, as specified in Section 3.2.3 of this document.

4.2.  AuthEnvelopedData Using 1-Pass ECMQV

  This section describes how to use the 1-Pass ECMQV key agreement
  algorithm with AuthEnvelopedData.  ECMQV is method C(1, 2, ECC MQV)
  from [SP800-56A].

  When using ECMQV with AuthEnvelopedData, the fields of
  AuthEnvelopedData are as in [CMS-AUTHENV].

  As 1-Pass ECMQV is a key agreement algorithm, the RecipientInfo kari
  choice is used.  When using 1-Pass ECMQV, the AuthEnvelopedData
  originatorInfo field MAY include the certificate(s) for the EC public
  key used in the formation of the pairwise key.  ECC certificates are
  discussed in Section 5.

4.2.1.  Fields of the KeyAgreeRecipientInfo

  The AuthEnvelopedData KeyAgreeRecipientInfo fields are used in the
  same manner as the fields for the corresponding EnvelopedData
  KeyAgreeRecipientInfo fields of Section 3.2.1 of this document.





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4.2.2.  Actions of the Sending Agent

  The sending agent uses the same actions as for EnvelopedData with
  1-Pass ECMQV, as specified in Section 3.2.2 of this document.

  In a single message, if there are multiple layers for a recipient,
  then the ephemeral public key can be reused by the originator for
  that recipient in each of the different layers.

4.2.3.  Actions of the Receiving Agent

  The receiving agent uses the same actions as for EnvelopedData with
  1-Pass ECMQV, as specified in Section 3.2.3 of this document.

5.  Certificates Using ECC

  Internet X.509 certificates [PKI] can be used in conjunction with
  this specification to distribute agents' public keys.  The use of ECC
  algorithms and keys within X.509 certificates is specified in
  [PKI-ALG].

6.  SMIMECapabilities Attribute and ECC

  A sending agent MAY announce to receiving agents that it supports one
  or more of the ECC algorithms specified in this document by using the
  SMIMECapabilities signed attribute [MSG] in either a signed message
  or a certificate [CERTCAP].

  The SMIMECapabilities attribute value indicates support for one of
  the ECDSA signature algorithms in a SEQUENCE with the capabilityID
  field containing the object identifier ecdsa-with-SHA1 with NULL
  parameters and ecdsa-with-SHA* (where * is 224, 256, 384, or 512)
  with absent parameters.  The DER encodings are:

     ecdsa-with-SHA1:   30 0b 06 07 2a 86 48 ce 3d 04 01 05 00

     ecdsa-with-SHA224: 30 0a 06 08 2a 86 48 ce 3d 04 03 01

     ecdsa-with-SHA256: 30 0a 06 08 2a 86 48 ce 3d 04 03 02

     ecdsa-with-SHA384: 30 0a 06 08 2a 86 48 ce 3d 04 03 03

     ecdsa-with-SHA512: 30 0a 06 08 2a 86 48 ce 3d 04 03 04

  NOTE: The SMIMECapabilities attribute indicates that parameters for
  ECDSA with SHA-1 are NULL; however, the parameters are absent when
  used to generate a digital signature.




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  The SMIMECapabilities attribute value indicates support for

     a)  the standard ECDH key agreement algorithm,
     b)  the cofactor ECDH key agreement algorithm, or
     c)  the 1-Pass ECMQV key agreement algorithm and

  is a SEQUENCE with the capabilityID field containing the object
  identifier

     a)  dhSinglePass-stdDH-sha*kdf-scheme,
     b)  dhSinglePass-cofactorDH-sha*kdf-scheme, or
     c)  mqvSinglePass-sha*kdf-scheme

  respectively (where * is 1, 224, 256, 384, or 512) with the
  parameters present.  The parameters indicate the supported key-
  encryption algorithm with the KeyWrapAlgorithm algorithm identifier.

  The DER encodings that indicate capabilities are as follows (KA is
  key agreement, KDF is key derivation function, and Wrap is key wrap
  algorithm):

     KA=ECDH standard KDF=SHA-1 Wrap=Triple-DES

       30 1c 06 09 2b 81 05 10 86 48 3f 00 02 30 0f 06 0b 2a 86 48 86
       f7 0d 01 09 10 03 06 05 00

     KA=ECDH standard KDF=SHA-224 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0B 00 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECDH standard KDF=SHA-256 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0B 01 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECDH standard KDF=SHA-384 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0B 02 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECDH standard KDF=SHA-512 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0B 03 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06






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     KA=ECDH standard KDF=SHA-1 Wrap=AES-128

       30 18 06 09 2b 81 05 10 86 48 3f 00 02 30 0b 06 09 60 86 48 01
       65 03 04 01 05

     KA=ECDH standard KDF=SHA-224 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0B 00 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECDH standard KDF=SHA-256 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0B 01 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECDH standard KDF=SHA-384 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0B 02 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECDH standard KDF=SHA-512 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0B 03 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECDH standard KDF=SHA-1 Wrap=AES-192

       30 18 06 09 2b 81 05 10 86 48 3f 00 02 30 0b 06 09 60 86 48 01
       65 03 04 01 19

     KA=ECDH standard KDF=SHA-224 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0B 00 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECDH standard KDF=SHA-256 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0B 01 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECDH standard KDF=SHA-384 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0B 02 30 0b 06 09 60 86 48 01 65 03 04
       01 19







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     KA=ECDH standard KDF=SHA-512 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0B 03 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECDH standard KDF=SHA-1 Wrap=AES-256

       30 18 06 09 2b 81 05 10 86 48 3f 00 02 30 0b 06 09 60 86 48 01
       65 03 04 01 2D

     KA=ECDH standard KDF=SHA-224 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0B 00 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECDH standard KDF=SHA-256 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0B 01 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECDH standard KDF=SHA-384 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0B 02 30 0b 06 09 60 86 48 01 65 03 04
       01 2D 05 00

     KA=ECDH standard KDF=SHA-512 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0B 03 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECDH cofactor KDF=SHA-1 Wrap=Triple-DES

       30 1c 06 09 2b 81 05 10 86 48 3f 00 03 30 0f 06 0b 2a 86 48 86
       f7 0d 01 09 10 03 06 05 00

     KA=ECDH cofactor KDF=SHA-224 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0E 00 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECDH cofactor KDF=SHA-256 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0E 01 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06







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     KA=ECDH cofactor KDF=SHA-384 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0E 02 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECDH cofactor KDF=SHA-512 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0E 03 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECDH cofactor KDF=SHA-1 Wrap=AES-128

       30 18 06 09 2b 81 05 10 86 48 3f 00 03 30 0b 06 09 60 86 48 01
       65 03 04 01 05

     KA=ECDH cofactor KDF=SHA-224 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0E 00 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECDH cofactor KDF=SHA-256 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0E 01 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECDH cofactor KDF=SHA-384 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0E 02 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECDH cofactor KDF=SHA-512 Wrap=AES-128

       30 17 06 06 2b 81 04 01 0E 03 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECDH cofactor KDF=SHA-1 Wrap=AES-192

       30 18 06 09 2b 81 05 10 86 48 3f 00 03 30 0b 06 09 60 86 48 01
       65 03 04 01 19

     KA=ECDH cofactor KDF=SHA-224 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0E 00 30 0b 06 09 60 86 48 01 65 03 04
       01 19







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     KA=ECDH cofactor KDF=SHA-256 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0E 01 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECDH cofactor KDF=SHA-384 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0E 02 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECDH cofactor KDF=SHA-512 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0E 03 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECDH cofactor KDF=SHA-1 Wrap=AES-256

       30 15 06 09 2b 81 05 10 86 48 3f 00 03 30 0b 06 09 60 86 48 01
       65 03 04 01 2D

     KA=ECDH cofactor KDF=SHA-224 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0E 00 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECDH cofactor KDF=SHA-256 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0E 01 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECDH cofactor KDF=SHA-384 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0E 02 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECDH cofactor KDF=SHA-512 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0E 03 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECMQV 1-Pass KDF=SHA-1 Wrap=Triple-DES

       30 1c 06 09 2b 81 05 10 86 48 3f 00 10 30 0f 06 0b 2a 86 48 86
       f7 0d 01 09 10 03 06 05 00







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     KA=ECMQV 1-Pass KDF=SHA-224 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0F 00 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECMQV 1-Pass KDF=SHA-256 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0F 01 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECMQV 1-Pass KDF=SHA-384 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0F 02 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECMQV 1-Pass KDF=SHA-512 Wrap=Triple-DES

       30 17 06 06 2b 81 04 01 0F 03 30 0d 06 0b 2a 86 48 86 f7 0d 01
       09 10 03 06

     KA=ECMQV 1-Pass KDF=SHA-1 Wrap=AES-128

       30 18 06 09 2b 81 05 10 86 48 3f 00 10 30 0b 06 09 60 86 48 01
       65 03 04 01 05

     KA=ECMQV 1-Pass KDF=SHA-224 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0F 00 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECMQV 1-Pass KDF=SHA-256 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0F 01 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECMQV 1-Pass KDF=SHA-384 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0F 02 30 0b 06 09 60 86 48 01 65 03 04
       01 05

     KA=ECMQV 1-Pass KDF=SHA-512 Wrap=AES-128

       30 15 06 06 2b 81 04 01 0F 03 30 0b 06 09 60 86 48 01 65 03 04
       01 05







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     KA=ECMQV 1-Pass KDF=SHA-1 Wrap=AES-192

       30 18 06 09 2b 81 05 10 86 48 3f 00 10 30 0b 06 09 60 86 48 01
       65 03 04 01 19

     KA=ECMQV 1-Pass KDF=SHA-224 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0F 00 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECMQV 1-Pass KDF=SHA-256 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0F 01 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECMQV 1-Pass KDF=SHA-384 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0F 02 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECMQV 1-Pass KDF=SHA-512 Wrap=AES-192

       30 15 06 06 2b 81 04 01 0F 03 30 0b 06 09 60 86 48 01 65 03 04
       01 19

     KA=ECMQV 1-Pass KDF=SHA-1 Wrap=AES-256

       30 18 06 09 2b 81 05 10 86 48 3f 00 10 30 0b 06 09 60 86 48 01
       65 03 04 01 2D

     KA=ECMQV 1-Pass KDF=SHA-224 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0F 00 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECMQV 1-Pass KDF=SHA-256 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0F 01 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

     KA=ECMQV 1-Pass KDF=SHA-384 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0F 02 30 0b 06 09 60 86 48 01 65 03 04
       01 2D







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     KA=ECMQV 1-Pass KDF=SHA-512 Wrap=AES-256

       30 15 06 06 2b 81 04 01 0F 03 30 0b 06 09 60 86 48 01 65 03 04
       01 2D

  NOTE: The S/MIME Capabilities for the supported AES content-
  encryption key sizes are defined in [CMS-AES].

  NOTE: The S/MIME Capabilities for the supported MAC algorithms are
  defined in [CMS-ASN].

7.  ASN.1 Syntax

  The ASN.1 syntax [X.680], [X.681], [X.682], [X.683] used in this
  document is gathered in this section for reference purposes.

7.1.  Algorithm Identifiers

  This section provides the object identifiers for the algorithms used
  in this document along with any associated parameters.

7.1.1.  Digest Algorithms

  Digest algorithm object identifiers are used in the SignedData
  digestAlgorithms and digestAlgorithm fields and the AuthenticatedData
  digestAlgorithm field.  The digest algorithms used in this document
  are SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512.  The object
  identifiers and parameters associated with these algorithms are found
  in [CMS-ALG] and [CMS-SHA2].

7.1.2.  Originator Public Key

  The KeyAgreeRecipientInfo originator field uses the following object
  identifier to indicate an elliptic curve public key:

     id-ecPublicKey OBJECT IDENTIFIER ::= {
       ansi-x9-62 keyType(2) 1 }

  where

     ansi-x9-62 OBJECT IDENTIFIER ::= {
       iso(1) member-body(2) us(840) 10045 }

  When the object identifier id-ecPublicKey is used here with an
  algorithm identifier, the associated parameters MUST be either absent
  or ECParameters.  Implementations MUST accept id-ecPublicKey with
  absent and ECParameters parameters.  If ECParameters is present, its




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  value MUST match the recipient's ECParameters.  Implementations
  SHOULD generate absent parameters for the id-ecPublicKey object
  identifier in the KeyAgreeRecipientInfo originator field.

  [CMS-ECC] indicated the parameters were NULL.  Support for this
  legacy form is OPTIONAL.

7.1.3.  Signature Algorithms

  Signature algorithm identifiers are used in the SignedData
  signatureAlgorithm and signature fields.  The signature algorithms
  used in this document are ECDSA with SHA-1, ECDSA with SHA-224, ECDSA
  with SHA-256, ECDSA with SHA-384, and ECDSA with SHA-512.  The object
  identifiers and parameters associated with these algorithms are found
  in [PKI-ALG].

  [CMS-ECC] indicated the parameters were NULL.  Support for this
  legacy form is OPTIONAL.

7.1.4.  Key Agreement Algorithms

  Key agreement algorithms are used in EnvelopedData,
  AuthenticatedData, and AuthEnvelopedData in the KeyAgreeRecipientInfo
  keyEncryptionAlgorithm field.  The following object identifiers
  indicate the key agreement algorithms used in this document
  [SP800-56A], [SEC1]:

     dhSinglePass-stdDH-sha1kdf-scheme OBJECT IDENTIFIER ::= {
       x9-63-scheme 2 }

     dhSinglePass-stdDH-sha224kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 11 0 }

     dhSinglePass-stdDH-sha256kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 11 1 }

     dhSinglePass-stdDH-sha384kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 11 2 }

     dhSinglePass-stdDH-sha512kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 11 3 }

     dhSinglePass-cofactorDH-sha1kdf-scheme OBJECT IDENTIFIER ::= {
       x9-63-scheme 3 }

     dhSinglePass-cofactorDH-sha224kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 14 0 }




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     dhSinglePass-cofactorDH-sha256kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 14 1 }

     dhSinglePass-cofactorDH-sha384kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 14 2 }

     dhSinglePass-cofactorDH-sha512kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 14 3 }

     mqvSinglePass-sha1kdf-scheme OBJECT IDENTIFIER ::= {
       x9-63-scheme 16 }

     mqvSinglePass-sha224kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 15 0 }

     mqvSinglePass-sha256kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 15 1 }

     mqvSinglePass-sha384kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 15 2 }

     mqvSinglePass-sha512kdf-scheme OBJECT IDENTIFIER ::= {
       secg-scheme 15 3 }

  where

     x9-63-scheme OBJECT IDENTIFIER ::= {
       iso(1) identified-organization(3) tc68(133) country(16)
       x9(840) x9-63(63) schemes(0) }

  and

     secg-scheme OBJECT IDENTIFIER ::= {
       iso(1) identified-organization(3) certicom(132) schemes(1) }

  When the object identifiers are used here within an algorithm
  identifier, the associated parameters field contains KeyWrapAlgorithm
  to indicate the key wrap algorithm and any associated parameters.

7.1.5.  Key Wrap Algorithms

  Key wrap algorithms are used as part of the parameters in the key
  agreement algorithm.  The key wrap algorithms used in this document
  are Triple-DES, AES-128, AES-192, and AES-256.  The object
  identifiers and parameters for these algorithms are found in
  [CMS-ALG] and [CMS-AES].





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7.1.6.  Content Encryption Algorithms

  Content encryption algorithms are used in EnvelopedData and
  AuthEnvelopedData in the EncryptedContentInfo
  contentEncryptionAlgorithm field.  The content encryption algorithms
  used with EnvelopedData in this document are 3-Key Triple DES in CBC
  mode, AES-128 in CBC mode, AES-192 in CBC mode, and AES-256 in CBC
  mode.  The object identifiers and parameters associated with these
  algorithms are found in [CMS-ALG] and [CMS-AES].  The content
  encryption algorithms used with AuthEnvelopedData in this document
  are AES-128 in CCM mode, AES-192 in CCM mode, AES-256 in CCM mode,
  AES-128 in GCM mode, AES-192 in GCM mode, and AES-256 in GCM mode.
  The object identifiers and parameters associated with these
  algorithms are found in [CMS-AESCG].

7.1.7.  Message Authentication Code Algorithms

  Message authentication code algorithms are used in AuthenticatedData
  in the macAlgorithm field.  The message authentication code
  algorithms used in this document are HMAC with SHA-1, HMAC with
  SHA-224, HMAC with SHA-256, HMAC with SHA-384, and HMAC with SHA-512.
  The object identifiers and parameters associated with these
  algorithms are found in [CMS-ALG] and [HMAC-SHA2].

  NOTE: [HMAC-SHA2] defines the object identifiers for HMAC with
  SHA-224, HMAC with SHA-256, HMAC with SHA-384, and HMAC with SHA-512,
  but there is no ASN.1 module from which to import these object
  identifiers.  Therefore, the object identifiers for these algorithms
  are included in the ASN.1 modules defined in Appendix A.

7.1.8.  Key Derivation Algorithm

  The KDF used in this document is as specified in Section 3.6.1 of
  [SEC1].  The hash algorithm is identified in the key agreement
  algorithm.  For example, dhSinglePass-stdDH-sha256kdf-scheme uses the
  KDF from [SEC1] but uses SHA-256 instead of SHA-1.

7.2.  Other Syntax

  The following additional syntax is used here.

  When using ECDSA with SignedData, ECDSA signatures are encoded using
  the type:

     ECDSA-Sig-Value ::= SEQUENCE {
       r INTEGER,
       s INTEGER }




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  ECDSA-Sig-Value is specified in [PKI-ALG].  Within CMS, ECDSA-Sig-
  Value is DER-encoded and placed within a signature field of
  SignedData.

  When using ECDH and ECMQV with EnvelopedData, AuthenticatedData, and
  AuthEnvelopedData, ephemeral and static public keys are encoded using
  the type ECPoint.  Implementations MUST support uncompressed keys,
  MAY support compressed keys, and MUST NOT support hybrid keys.

     ECPoint ::= OCTET STRING

  When using ECMQV with EnvelopedData, AuthenticatedData, and
  AuthEnvelopedData, the sending agent's ephemeral public key and
  additional keying material are encoded using the type:

     MQVuserKeyingMaterial ::= SEQUENCE {
       ephemeralPublicKey      OriginatorPublicKey,
       addedukm            [0] EXPLICIT UserKeyingMaterial OPTIONAL  }

  The ECPoint syntax is used to represent the ephemeral public key and
  is placed in the ephemeralPublicKey publicKey field.  The additional
  user keying material is placed in the addedukm field.  Then the
  MQVuserKeyingMaterial value is DER-encoded and placed within the ukm
  field of EnvelopedData, AuthenticatedData, or AuthEnvelopedData.

  When using ECDH or ECMQV with EnvelopedData, AuthenticatedData, or
  AuthEnvelopedData, the key-encryption keys are derived by using the
  type:

     ECC-CMS-SharedInfo ::= SEQUENCE {
       keyInfo         AlgorithmIdentifier,
       entityUInfo [0] EXPLICIT OCTET STRING OPTIONAL,
       suppPubInfo [2] EXPLICIT OCTET STRING  }

  The fields of ECC-CMS-SharedInfo are as follows:

     keyInfo contains the object identifier of the key-encryption
     algorithm (used to wrap the CEK) and associated parameters.  In
     this specification, 3DES wrap has NULL parameters while the AES
     wraps have absent parameters.

     entityUInfo optionally contains additional keying material
     supplied by the sending agent.  When used with ECDH and CMS, the
     entityUInfo field contains the octet string ukm.  When used with
     ECMQV and CMS, the entityUInfo contains the octet string addedukm
     (encoded in MQVuserKeyingMaterial).





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     suppPubInfo contains the length of the generated KEK, in bits,
     represented as a 32-bit number, as in [CMS-DH] and [CMS-AES].
     (For example, for AES-256 it would be 00 00 01 00.)

  Within CMS, ECC-CMS-SharedInfo is DER-encoded and used as input to
  the key derivation function, as specified in Section 3.6.1 of [SEC1].

  NOTE: ECC-CMS-SharedInfo differs from the OtherInfo specified in
  [CMS-DH].  Here, a counter value is not included in the keyInfo field
  because the key derivation function specified in Section 3.6.1 of
  [SEC1] ensures that sufficient keying data is provided.

8.  Recommended Algorithms and Elliptic Curves

  It is RECOMMENDED that implementations of this specification support
  SignedData and EnvelopedData.  Support for AuthenticatedData and
  AuthEnvelopedData is OPTIONAL.

  In order to encourage interoperability, implementations SHOULD use
  the elliptic curve domain parameters specified by [PKI-ALG].

  Implementations that support SignedData with ECDSA:

     - MUST support ECDSA with SHA-256; and

     - MAY support ECDSA with SHA-1, ECDSA with SHA-224, ECDSA with
       SHA-384, and ECDSA with SHA-512; other digital signature
       algorithms MAY also be supported.

  When using ECDSA, to promote interoperability it is RECOMMENDED that
  the P-192, P-224, and P-256 curves be used with SHA-256; the P-384
  curve be used with SHA-384; and the P-521 curve be used with SHA-512.

  If EnvelopedData is supported, then ephemeral-static ECDH standard
  primitive MUST be supported.  Support for ephemeral-static ECDH co-
  factor is OPTIONAL, and support for 1-Pass ECMQV is also OPTIONAL.

  Implementations that support EnvelopedData with the ephemeral-static
  ECDH standard primitive:

     - MUST support the dhSinglePass-stdDH-sha256kdf-scheme key
       agreement algorithm, the id-aes128-wrap key wrap algorithm, and
       the id-aes128-cbc content encryption algorithm; and








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     - MAY support the dhSinglePass-stdDH-sha1kdf-scheme, dhSinglePass-
       stdDH-sha224kdf-scheme, dhSinglePass-stdDH-sha384kdf-scheme, and
       dhSinglePass-stdDH-sha512kdf-scheme key agreement algorithms;
       the id-alg-CMS3DESwrap, id-aes192-wrap, and id-aes256-wrap key
       wrap algorithms; and the des-ede3-cbc, id-aes192-cbc, and id-
       aes256-cbc content encryption algorithms; other algorithms MAY
       also be supported.

  Implementations that support EnvelopedData with the ephemeral-static
  ECDH cofactor primitive:

     - MUST support the dhSinglePass-cofactorDH-sha256kdf-scheme key
       agreement algorithm, the id-aes128-wrap key wrap algorithm, and
       the id-aes128-cbc content encryption algorithm; and

     - MAY support the dhSinglePass-cofactorDH-sha1kdf-scheme,
       dhSinglePass-cofactorDH-sha224kdf-scheme, dhSinglePass-
       cofactorDH-sha384kdf-scheme, and dhSinglePass-cofactorDH-
       sha512kdf-scheme key agreement; the id-alg-CMS3DESwrap, id-
       aes192-wrap, and id-aes256-wrap key wrap algorithms; and the
       des-ede3-cbc, id-aes192-cbc, and id-aes256-cbc content
       encryption algorithms; other algorithms MAY also be supported.

  Implementations that support EnvelopedData with 1-Pass ECMQV:

     - MUST support the mqvSinglePass-sha256kdf-scheme key agreement
       algorithm, the id-aes128-wrap key wrap algorithm, and the id-
       aes128-cbc content encryption algorithm; and

     - MAY support the mqvSinglePass-sha1kdf-scheme, mqvSinglePass-
       sha224kdf-scheme, mqvSinglePass-sha384kdf-scheme, and
       mqvSinglePass-sha512kdf-scheme key agreement algorithms; the id-
       alg-CMS3DESwrap, id-aes192-wrap, and id-aes256-wrap key wrap
       algorithms; and the des-ede3-cbc, id-aes192-cbc, and id-
       aes256-cbc content encryption algorithms; other algorithms MAY
       also be supported.

  Implementations that support AuthenticatedData with 1-Pass ECMQV:

     - MUST support the mqvSinglePass-sha256kdf-scheme key agreement,
       the id-aes128-wrap key wrap, the id-sha256 message digest, and
       id-hmacWithSHA256 message authentication code algorithms; and

     - MAY support the mqvSinglePass-sha1kdf-scheme, mqvSinglePass-
       sha224kdf-scheme, mqvSinglePass-sha384kdf-scheme, mqvSinglePass-
       sha512kdf-scheme key agreement algorithms; the id-alg-
       CMS3DESwrap, id-aes192-wrap, and id-aes256-wrap key wrap
       algorithms; the id-sha1, id-sha224, id-sha384, and id-sha512,



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       message digest algorithms; and the hmac-SHA1, id-hmacWithSHA224,
       id-hmacWithSHA384, and id-hmacWithSHA512 message authentication
       code algorithms; other algorithms MAY also be supported.

  Implementations that support AuthEnvelopedData with 1-Pass ECMQV:

     - MUST support the mqvSinglePass-sha256kdf-scheme key agreement,
       the id-aes128-wrap key wrap, and the id-aes128-ccm
       authenticated-content encryption; and

     - MAY support the mqvSinglePass-sha1kdf-scheme, mqvSinglePass-
       sha224kdf-scheme, mqvSinglePass-sha384kdf-scheme, and
       mqvSinglePass-sha512kdf-scheme key agreement algorithms; the id-
       alg-CMS3DESwrap, id-aes192-wrap, and id-aes256-wrap key wrap
       algorithms; and the id-aes192-ccm, id-aes256-ccm, id-aes128-gcm,
       id-aes192-gcm, and id-aes256-ccm authenticated-content
       encryption algorithms; other algorithms MAY also be supported.

9.  Security Considerations

  Cryptographic algorithms will be broken or weakened over time.
  Implementers and users need to check that the cryptographic
  algorithms listed in this document continue to provide the expected
  level of security.  The IETF from time to time may issue documents
  dealing with the current state of the art.

  Cryptographic algorithms rely on random numbers.  See [RANDOM] for
  guidance on generation of random numbers.

  Receiving agents that validate signatures and sending agents that
  encrypt messages need to be cautious of cryptographic processing
  usage when validating signatures and encrypting messages using keys
  larger than those mandated in this specification.  An attacker could
  send keys and/or certificates with keys that would result in
  excessive cryptographic processing, for example, keys larger than
  those mandated in this specification, which could swamp the
  processing element.  Agents that use such keys without first
  validating the certificate to a trust anchor are advised to have some
  sort of cryptographic resource management system to prevent such
  attacks.

  Using secret keys of an appropriate size is crucial to the security
  of a Diffie-Hellman exchange.  For elliptic curve groups, the size of
  the secret key must be equal to the size of n (the order of the group
  generated by the point g).  Using larger secret keys provides
  absolutely no additional security, and using smaller secret keys is
  likely to result in dramatically less security.  (See [SP800-56A] for
  more information on selecting secret keys.)



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  This specification is based on [CMS], [CMS-AES], [CMS-AESCG],
  [CMS-ALG], [CMS-AUTHENV], [CMS-DH], [CMS-SHA2], [FIPS180-3],
  [FIPS186-3], and [HMAC-SHA2], and the appropriate security
  considerations of those documents apply.

  In addition, implementers of AuthenticatedData and AuthEnvelopedData
  should be aware of the concerns expressed in [BON] when using
  AuthenticatedData and AuthEnvelopedData to send messages to more than
  one recipient.  Also, users of MQV should be aware of the
  vulnerability described in [K].

  When implementing EnvelopedData, AuthenticatedData, and
  AuthEnvelopedData, there are five algorithm-related choices that need
  to be made:

     1) What is the public key size?
     2) What is the KDF?
     3) What is the key wrap algorithm?
     4) What is the content encryption algorithm?
     5) What is the curve?

  Consideration must be given to the strength of the security provided
  by each of these choices.  Security algorithm strength is measured in
  bits, where bits is measured in equivalence to a symmetric cipher
  algorithm.  Thus, a strong symmetric cipher algorithm with a key of X
  bits is said to provide X bits of security.  For other algorithms,
  the key size is mapped to an equivalent symmetric cipher strength.
  It is recommended that the bits of security provided by each are
  roughly equivalent.  The following table provides comparable minimum
  bits of security [SP800-57] for the ECDH/ECMQV key sizes, KDFs, key
  wrapping algorithms, and content encryption algorithms.  It also
  lists curves [PKI-ALG] for the key sizes.



















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  Minimum  | ECDH or  | Key        | Key      | Content     | Curves
  Bits of  | ECMQV    | Derivation | Wrap     | Encryption  |
  Security | Key Size | Function   | Alg.     | Alg.        |
  ---------+----------+------------+----------+-------------+----------
  80       | 160-223  | SHA-1      | 3DES     | 3DES CBC    | sect163k1
           |          | SHA-224    | AES-128  | AES-128 CBC | secp163r2
           |          | SHA-256    | AES-192  | AES-192 CBC | secp192r1
           |          | SHA-384    | AES-256  | AES-256 CBC |
           |          | SHA-512    |          |             |
  ---------+----------+------------+----------+-------------+---------
  112      | 224-255  | SHA-1      | 3DES     | 3DES CBC    | secp224r1
           |          | SHA-224    | AES-128  | AES-128 CBC | sect233k1
           |          | SHA-256    | AES-192  | AES-192 CBC | sect233r1
           |          | SHA-384    | AES-256  | AES-256 CBC |
           |          | SHA-512    |          |             |
  ---------+----------+------------+----------+-------------+---------
  128      | 256-383  | SHA-1      | AES-128  | AES-128 CBC | secp256r1
           |          | SHA-224    | AES-192  | AES-192 CBC | sect283k1
           |          | SHA-256    | AES-256  | AES-256 CBC | sect283r1
           |          | SHA-384    |          |             |
           |          | SHA-512    |          |             |
  ---------+----------+------------+----------+-------------+---------
  192      | 384-511  | SHA-224    | AES-192  | AES-192 CBC | secp384r1
           |          | SHA-256    | AES-256  | AES-256 CBC | sect409k1
           |          | SHA-384    |          |             | sect409r1
           |          | SHA-512    |          |             |
  ---------+----------+------------+----------+-------------+---------
  256      | 512+     | SHA-256    | AES-256  | AES-256 CBC | secp521r1
           |          | SHA-384    |          |             | sect571k1
           |          | SHA-512    |          |             | sect571r1
  ---------+----------+------------+----------+-------------+---------




















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  To promote interoperability, the following choices are RECOMMENDED:

  Minimum  | ECDH or  | Key        | Key      | Content     | Curve
  Bits of  | ECMQV    | Derivation | Wrap     | Encryption  |
  Security | Key Size | Function   | Alg.     | Alg.        |
  ---------+----------+------------+----------+-------------+----------
  80       | 192      | SHA-256    | 3DES     | 3DES CBC    | secp192r1
  ---------+----------+------------+----------+-------------+----------
  112      | 224      | SHA-256    | 3DES     | 3DES CBC    | secp224r1
  ---------+----------+------------+----------+-------------+----------
  128      | 256      | SHA-256    | AES-128  | AES-128 CBC | secp256r1
  ---------+----------+------------+----------+-------------+----------
  192      | 384      | SHA-384    | AES-256  | AES-256 CBC | secp384r1
  ---------+----------+------------+----------+-------------+----------
  256      | 512+     | SHA-512    | AES-256  | AES-256 CBC | secp521r1
  ---------+----------+------------+----------+-------------+----------

  When implementing SignedData, there are three algorithm-related
  choices that need to be made:

     1) What is the public key size?
     2) What is the hash algorithm?
     3) What is the curve?

  Consideration must be given to the bits of security provided by each
  of these choices.  Security is measured in bits, where a strong
  symmetric cipher with a key of X bits is said to provide X bits of
  security.  It is recommended that the bits of security provided by
  each choice are roughly equivalent.  The following table provides
  comparable minimum bits of security [SP800-57] for the ECDSA key
  sizes and message digest algorithms.  It also lists curves [PKI-ALG]
  for the key sizes.



















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  Minimum  | ECDSA    | Message   | Curve
  Bits of  | Key Size | Digest    |
  Security |          | Algorithm |
  ---------+----------+-----------+-----------
  80       | 160-223  | SHA-1     | sect163k1
           |          | SHA-224   | secp163r2
           |          | SHA-256   | secp192r1
           |          | SHA-384   |
           |          | SHA-512   |
  ---------+----------+-----------+-----------
  112      | 224-255  | SHA-224   | secp224r1
           |          | SHA-256   | sect233k1
           |          | SHA-384   | sect233r1
           |          | SHA-512   |
  ---------+----------+-----------+-----------
  128      | 256-383  | SHA-256   | secp256r1
           |          | SHA-384   | sect283k1
           |          | SHA-512   | sect283r1
  ---------+----------+-----------+-----------
  192      | 384-511  | SHA-384   | secp384r1
           |          | SHA-512   | sect409k1
           |          |           | sect409r1
  ---------+----------+-----------+-----------
  256      | 512+     | SHA-512   | secp521r1
           |          |           | sect571k1
           |          |           | sect571r1
  ---------+----------+-----------+-----------

  To promote interoperability, the following choices are RECOMMENDED:

  Minimum  | ECDSA    | Message   | Curve
  Bits of  | Key Size | Digest    |
  Security |          | Algorithm |
  ---------+----------+-----------+-----------
  80       | 192      | SHA-256   | sect192r1
  ---------+----------+-----------+-----------
  112      | 224      | SHA-256   | secp224r1
  ---------+----------+-----------+-----------
  128      | 256      | SHA-256   | secp256r1
  ---------+----------+-----------+-----------
  192      | 384      | SHA-384   | secp384r1
  ---------+----------+-----------+-----------
  256      | 512+     | SHA-512   | secp521r1
  ---------+----------+-----------+-----------







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RFC 5753              Use of ECC Algorithms in CMS          January 2010


10.  IANA Considerations

  This document makes extensive use of object identifiers to register
  originator public key types and algorithms.  The algorithm object
  identifiers are registered in the ANSI X9.62, ANSI X9.63, NIST, RSA,
  and SECG arcs.  Additionally, object identifiers are used to identify
  the ASN.1 modules found in Appendix A (there are two).  These are
  defined by the SMIME WG Registrar in an arc delegated by RSA to the
  SMIME Working Group: iso(1) member-body(2) us(840) rsadsi(113549)
  pkcs(1) pkcs-9(9) smime(16) modules(0).  No action by IANA is
  necessary for this document or any anticipated updates.

11.  References

11.1.  Normative References

  [CMS]          Housley, R., "Cryptographic Message Syntax (CMS)", RFC
                 5652, September 2009.

  [CMS-AES]      Schaad, J., "Use of the Advanced Encryption Standard
                 (AES) Encryption Algorithm in Cryptographic Message
                 Syntax (CMS)", RFC 3565, July 2003.

  [CMS-AESCG]    Housley, R., "Using AES-CCM and AES-GCM Authenticated
                 Encryption in the Cryptographic Message Syntax (CMS)",
                 RFC 5084, December 2007.

  [CMS-ALG]      Housley, R., "Cryptographic Message Syntax (CMS)
                 Algorithms", RFC 3370, August 2002.

  [CMS-AUTHENV]  Housley, R., "Cryptographic Message Syntax (CMS)
                 Authenticated-Enveloped-Data Content Type", RFC 5083,
                 November 2007.

  [CMS-DH]       Rescorla, E., "Diffie-Hellman Key Agreement Method",
                 RFC 2631, June 1999.

  [CMS-SHA2]     Turner, S., "Using SHA2 Algorithms with Cryptographic
                 Message Syntax", RFC 5754, January 2010.

  [FIPS180-3]    National Institute of Standards and Technology (NIST),
                 FIPS Publication 180-3: Secure Hash Standard, October
                 2008.

  [FIPS186-3]    National Institute of Standards and Technology (NIST),
                 FIPS Publication 186-3: Digital Signature Standard,
                 June 2009.




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RFC 5753              Use of ECC Algorithms in CMS          January 2010


  [HMAC-SHA2]    Nystrom, M., "Identifiers and Test Vectors for HMAC-
                 SHA-224, HMAC-SHA-256, HMAC-SHA-384, and HMAC-
                 SHA-512", RFC 4231, December 2005.

  [MUST]         Bradner, S., "Key words for use in RFCs to Indicate
                 Requirement Levels", BCP 14, RFC 2119, March 1997.

  [MSG]          Ramsdell, B. and S. Turner, "Secure/Multipurpose
                 Internet Mail Extensions (S/MIME) Version 3.2 Message
                 Specification", RFC 5751, January 2010.

  [PKI]          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, May 2008.

  [PKI-ALG]      Turner, S., Brown, D., Yiu, K., Housley, R., and T.
                 Polk, "Elliptic Curve Cryptography Subject Public Key
                 Information", RFC 5480, March 2009.

  [RANDOM]       Eastlake, D., 3rd, Schiller, J., and S. Crocker,
                 "Randomness Requirements for Security", BCP 106, RFC
                 4086, June 2005.

  [RSAOAEP]      Schaad, J., Kaliski, B., and R. Housley, "Additional
                 Algorithms and Identifiers for RSA Cryptography for
                 use in the Internet X.509 Public Key Infrastructure
                 Certificate and Certificate Revocation List (CRL)
                 Profile", RFC 4055, June 2005.

  [SEC1]         Standards for Efficient Cryptography Group, "SEC 1:
                 Elliptic Curve Cryptography", version 2.0, May 2009,
                 available from www.secg.org.

  [SP800-56A]    National Institute of Standards and Technology (NIST),
                 Special Publication 800-56A: Recommendation Pair-Wise
                 Key Establishment Schemes Using Discrete Logarithm
                 Cryptography (Revised), March 2007.

  [X.680]        ITU-T Recommendation X.680 (2002) | ISO/IEC
                 8824-1:2002. Information Technology - Abstract Syntax
                 Notation One.









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RFC 5753              Use of ECC Algorithms in CMS          January 2010


11.2.  Informative References

  [BON]          D. Boneh, "The Security of Multicast MAC",
                 Presentation at Selected Areas of Cryptography 2000,
                 Center for Applied Cryptographic Research, University
                 of Waterloo, 2000.  Paper version available from
                 http://crypto.stanford.edu/~dabo/papers/mmac.ps

  [CERTCAP]      Santesson, S., "X.509 Certificate Extension for
                 Secure/Multipurpose Internet Mail Extensions (S/MIME)
                 Capabilities", RFC 4262, December 2005.

  [CMS-ASN]      Hoffman, P. and J. Schaad, "New ASN.1 Modules for CMS
                 and S/MIME", Work in Progress, August 2009.

  [CMS-ECC]      Blake-Wilson, S., Brown, D., and P. Lambert, "Use of
                 Elliptic Curve Cryptography (ECC) Algorithms in
                 Cryptographic Message Syntax (CMS)", RFC 3278, April
                 2002.

  [CMS-KEA]      Pawling, J., "Use of the KEA and SKIPJACK Algorithms
                 in CMS", RFC 2876, July 2000.

  [K]            B. Kaliski, "MQV Vulnerability", Posting to ANSI X9F1
                 and IEEE P1363 newsgroups, 1998.

  [PKI-ASN]      Hoffman, P. and J. Schaad, "New ASN.1 Modules for
                 PKIX", Work in Progress, August 2009.

  [SP800-57]     National Institute of Standards and Technology (NIST),
                 Special Publication 800-57: Recommendation for Key
                 Management - Part 1 (Revised), March 2007.

  [X.681]        ITU-T Recommendation X.681 (2002) | ISO/IEC
                 8824-2:2002. Information Technology - Abstract Syntax
                 Notation One: Information Object Specification.

  [X.682]        ITU-T Recommendation X.682 (2002) | ISO/IEC
                 8824-3:2002. Information Technology - Abstract Syntax
                 Notation One: Constraint Specification.

  [X.683]        ITU-T Recommendation X.683 (2002) | ISO/IEC
                 8824-4:2002. Information Technology - Abstract Syntax
                 Notation One: Parameterization of ASN.1
                 Specifications, 2002.






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  [X9.62]        X9.62-2005, "Public Key Cryptography for the Financial
                 Services Industry: The Elliptic Curve Digital
                 Signature Standard (ECDSA)", November, 2005.
















































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Appendix A.   ASN.1 Modules

  Appendix A.1 provides the normative ASN.1 definitions for the
  structures described in this specification using ASN.1 as defined in
  [X.680] for compilers that support the 1988 ASN.1.

  Appendix A.2 provides informative ASN.1 definitions for the
  structures described in this specification using ASN.1 as defined in
  [X.680], [X.681], [X.682], and [X.683] for compilers that support the
  2002 ASN.1.  This appendix contains the same information as Appendix
  A.1 in a more recent (and precise) ASN.1 notation; however, Appendix
  A.1 takes precedence in case of conflict.

A.1.  1988 ASN.1 Module

  CMSECCAlgs-2009-88
    { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
      smime(16) modules(0) id-mod-cms-ecc-alg-2009-88(45) }

  DEFINITIONS IMPLICIT TAGS ::=

  BEGIN

  -- EXPORTS ALL

  IMPORTS

  -- From [PKI]

  AlgorithmIdentifier
    FROM PKIX1Explicit88
      { iso(1) identified-organization(3) dod(6)
        internet(1) security(5) mechanisms(5) pkix(7) mod(0)
        pkix1-explicit(18) }

  -- From [RSAOAEP]

  id-sha224, id-sha256, id-sha384, id-sha512
    FROM PKIX1-PSS-OAEP-Algorithms
      { iso(1) identified-organization(3) dod(6) internet(1)
        security(5) mechanisms(5) pkix(7) id-mod(0)
        id-mod-pkix1-rsa-pkalgs(33) }









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  -- From [PKI-ALG]

  id-sha1, ecdsa-with-SHA1, ecdsa-with-SHA224,
  ecdsa-with-SHA256, ecdsa-with-SHA384, ecdsa-with-SHA512,
  id-ecPublicKey, ECDSA-Sig-Value, ECPoint, ECParameters
    FROM PKIX1Algorithms2008
      { iso(1) identified-organization(3) dod(6) internet(1)
        security(5) mechanisms(5) pkix(7) id-mod(0) 45 }

  -- From [CMS]

  OriginatorPublicKey, UserKeyingMaterial
    FROM CryptographicMessageSyntax2004
      { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
        smime(16) modules(0) cms-2004(24) }

  -- From [CMS-ALG]

  hMAC-SHA1, des-ede3-cbc, id-alg-CMS3DESwrap, CBCParameter
    FROM CryptographicMessageSyntaxAlgorithms
      { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
        smime(16) modules(0) cmsalg-2001(16) }

  -- From [CMS-AES]

  id-aes128-CBC, id-aes192-CBC, id-aes256-CBC, AES-IV,
  id-aes128-wrap, id-aes192-wrap, id-aes256-wrap
    FROM CMSAesRsaesOaep
      { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
        smime(16) modules(0) id-mod-cms-aes(19) }

  -- From [CMS-AESCG]

  id-aes128-CCM, id-aes192-CCM, id-aes256-CCM, CCMParameters
  id-aes128-GCM, id-aes192-GCM, id-aes256-GCM, GCMParameters
    FROM CMS-AES-CCM-and-AES-GCM
      { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
        smime(16) modules(0) id-mod-cms-aes(32) }

  ;

  --
  -- Message Digest Algorithms: Imported from [PKI-ALG] and [RSAOAEP]
  --

  -- id-sha1 Parameters are preferred absent
  -- id-sha224 Parameters are preferred absent
  -- id-sha256 Parameters are preferred absent



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  -- id-sha384 Parameters are preferred absent
  -- id-sha512 Parameters are preferred absent

  --
  -- Signature Algorithms: Imported from [PKI-ALG]
  --

  -- ecdsa-with-SHA1 Parameters are NULL
  -- ecdsa-with-SHA224 Parameters are absent
  -- ecdsa-with-SHA256 Parameters are absent
  -- ecdsa-with-SHA384 Parameters are absent
  -- ecdsa-with-SHA512 Parameters are absent

  -- ECDSA Signature Value
  -- Contents of SignatureValue OCTET STRING

  -- ECDSA-Sig-Value ::= SEQUENCE {
  --   r  INTEGER,
  --   s  INTEGER
  -- }

  --
  -- Key Agreement Algorithms
  --

  x9-63-scheme OBJECT IDENTIFIER ::= {
    iso(1) identified-organization(3) tc68(133) country(16) x9(840)
    x9-63(63) schemes(0) }
  secg-scheme OBJECT IDENTIFIER ::= {
    iso(1) identified-organization(3) certicom(132) schemes(1) }

  --
  -- Diffie-Hellman Single Pass, Standard, with KDFs
  --

  -- Parameters are always present and indicate the key wrap algorithm
  -- with KeyWrapAlgorithm.

  dhSinglePass-stdDH-sha1kdf-scheme OBJECT IDENTIFIER ::= {
    x9-63-scheme 2 }

  dhSinglePass-stdDH-sha224kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 11 0 }

  dhSinglePass-stdDH-sha256kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 11 1 }





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RFC 5753              Use of ECC Algorithms in CMS          January 2010


  dhSinglePass-stdDH-sha384kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 11 2 }

  dhSinglePass-stdDH-sha512kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 11 3 }

  --
  -- Diffie-Hellman Single Pass, Cofactor, with KDFs
  --

  dhSinglePass-cofactorDH-sha1kdf-scheme OBJECT IDENTIFIER ::= {
    x9-63-scheme 3 }

  dhSinglePass-cofactorDH-sha224kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 14 0 }

  dhSinglePass-cofactorDH-sha256kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 14 1 }

  dhSinglePass-cofactorDH-sha384kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 14 2 }

  dhSinglePass-cofactorDH-sha512kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 14 3 }

  --
  -- MQV Single Pass, Cofactor, with KDFs
  --

  mqvSinglePass-sha1kdf-scheme OBJECT IDENTIFIER ::= {
    x9-63-scheme 16 }

  mqvSinglePass-sha224kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 15 0 }

  mqvSinglePass-sha256kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 15 1 }

  mqvSinglePass-sha384kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 15 2 }

  mqvSinglePass-sha512kdf-scheme OBJECT IDENTIFIER ::= {
    secg-scheme 15 3 }

  --
  -- Key Wrap Algorithms: Imported from [CMS-ALG] and [CMS-AES]
  --




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  KeyWrapAlgorithm ::= AlgorithmIdentifier

  -- id-alg-CMS3DESwrap Parameters are NULL
  -- id-aes128-wrap Parameters are absent
  -- id-aes192-wrap Parameters are absent
  -- id-aes256-wrap Parameters are absent

  --
  -- Content Encryption Algorithms: Imported from [CMS-ALG]
  -- and [CMS-AES]
  --

  -- des-ede3-cbc Parameters are CBCParameter
  -- id-aes128-CBC Parameters are AES-IV
  -- id-aes192-CBC Parameters are AES-IV
  -- id-aes256-CBC Parameters are AES-IV
  -- id-aes128-CCM Parameters are CCMParameters
  -- id-aes192-CCM Parameters are CCMParameters
  -- id-aes256-CCM Parameters are CCMParameters
  -- id-aes128-GCM Parameters are GCMParameters
  -- id-aes192-GCM Parameters are GCMParameters
  -- id-aes256-GCM Parameters are GCMParameters

  --
  -- Message Authentication Code Algorithms
  --

  -- hMAC-SHA1 Parameters are preferred absent

  -- HMAC with SHA-224, SHA-256, SHA_384, and SHA-512 Parameters are
  -- absent

  id-hmacWithSHA224 OBJECT IDENTIFIER ::= {
    iso(1) member-body(2) us(840) rsadsi(113549)
    digestAlgorithm(2) 8 }

  id-hmacWithSHA256 OBJECT IDENTIFIER ::= {
    iso(1) member-body(2) us(840) rsadsi(113549)
    digestAlgorithm(2) 9 }

  id-hmacWithSHA384 OBJECT IDENTIFIER ::= {
    iso(1) member-body(2) us(840) rsadsi(113549)
    digestAlgorithm(2) 10 }

  id-hmacWithSHA512 OBJECT IDENTIFIER ::= {
    iso(1) member-body(2) us(840) rsadsi(113549)
    digestAlgorithm(2) 11 }




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  --
  -- Originator Public Key Algorithms: Imported from [PKI-ALG]
  --

  -- id-ecPublicKey Parameters are absent, NULL, or ECParameters

  -- Format for both ephemeral and static public keys: Imported from
  -- [PKI-ALG]

  -- ECPoint ::= OCTET STRING

  -- ECParameters ::= CHOICE {
  --   namedCurve      OBJECT IDENTIFIER
  --   commented out in [PKI-ALG]  implicitCurve   NULL
  --   commented out in [PKI-ALG]  specifiedCurve  SpecifiedECDomain
  --   commented out in [PKI-ALG]  ...
  -- }
      -- implicitCurve and specifiedCurve MUST NOT be used in PKIX.
      -- Details for SpecifiedECDomain can be found in [X9.62].
      -- Any future additions to this CHOICE should be coordinated
      -- with ANSI X9.

  -- Format of KeyAgreeRecipientInfo ukm field when used with
  -- ECMQV

  MQVuserKeyingMaterial ::= SEQUENCE {
    ephemeralPublicKey       OriginatorPublicKey,
    addedukm             [0] EXPLICIT UserKeyingMaterial OPTIONAL
  }

  -- 'SharedInfo' for input to KDF when using ECDH and ECMQV with
  -- EnvelopedData, AuthenticatedData, or AuthEnvelopedData

  ECC-CMS-SharedInfo ::= SEQUENCE {
    keyInfo         AlgorithmIdentifier,
    entityUInfo [0] EXPLICIT OCTET STRING OPTIONAL,
    suppPubInfo [2] EXPLICIT OCTET STRING
  }

  --
  -- S/MIME Capabilities
  -- An identifier followed by type.
  --








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  --
  -- S/MIME Capabilities: Message Digest Algorithms
  --

  -- Found in [CMS-SHA2].

  --
  -- S/MIME Capabilities: Signature Algorithms
  --

  -- ecdsa-with-SHA1 Type NULL
  -- ecdsa-with-SHA224 Type absent
  -- ecdsa-with-SHA256 Type absent
  -- ecdsa-with-SHA384 Type absent
  -- ecdsa-with-SHA512 Type absent

  --
  -- S/MIME Capabilities: ECDH, Single Pass, Standard
  --

  -- dhSinglePass-stdDH-sha1kdf Type is the KeyWrapAlgorithm
  -- dhSinglePass-stdDH-sha224kdf Type is the KeyWrapAlgorithm
  -- dhSinglePass-stdDH-sha256kdf Type is the KeyWrapAlgorithm
  -- dhSinglePass-stdDH-sha384kdf Type is the KeyWrapAlgorithm
  -- dhSinglePass-stdDH-sha512kdf Type is the KeyWrapAlgorithm


  --
  -- S/MIME Capabilities: ECDH, Single Pass, Cofactor
  --

  -- dhSinglePass-cofactorDH-sha1kdf Type is the KeyWrapAlgorithm
  -- dhSinglePass-cofactorDH-sha224kdf Type is the KeyWrapAlgorithm
  -- dhSinglePass-cofactorDH-sha256kdf Type is the KeyWrapAlgorithm
  -- dhSinglePass-cofactorDH-sha384kdf Type is the KeyWrapAlgorithm
  -- dhSinglePass-cofactorDH-sha512kdf Type is the KeyWrapAlgorithm

  --
  -- S/MIME Capabilities: ECMQV, Single Pass, Standard
  --

  -- mqvSinglePass-sha1kdf Type is the KeyWrapAlgorithm
  -- mqvSinglePass-sha224kdf Type is the KeyWrapAlgorithm
  -- mqvSinglePass-sha256kdf Type is the KeyWrapAlgorithm
  -- mqvSinglePass-sha384kdf Type is the KeyWrapAlgorithm
  -- mqvSinglePass-sha512kdf Type is the KeyWrapAlgorithm





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  --
  -- S/MIME Capabilities: Message Authentication Code Algorithms
  --

  -- hMACSHA1 Type is preferred absent
  -- id-hmacWithSHA224 Type is absent
  -- if-hmacWithSHA256 Type is absent
  -- id-hmacWithSHA384 Type is absent
  -- id-hmacWithSHA512 Type is absent

  END








































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RFC 5753              Use of ECC Algorithms in CMS          January 2010


A.2.  2004 ASN.1 Module

CMSECCAlgs-2009-02
 { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
   smime(16) modules(0) id-mod-cms-ecc-alg-2009-02(46) }

DEFINITIONS IMPLICIT TAGS ::=

BEGIN

-- EXPORTS ALL

IMPORTS

-- From [PKI-ASN]

mda-sha1, sa-ecdsaWithSHA1, sa-ecdsaWithSHA224, sa-ecdsaWithSHA256,
sa-ecdsaWithSHA384, sa-ecdsaWithSHA512, id-ecPublicKey,
ECDSA-Sig-Value, ECPoint, ECParameters
 FROM PKIXAlgs-2009
   { iso(1) identified-organization(3) dod(6) internet(1)
     security(5) mechanisms(5) pkix(7) id-mod(0)
     id-mod-pkix1-algorithms2008-02(56) }

-- From [PKI-ASN]

mda-sha224, mda-sha256, mda-sha384, mda-sha512
 FROM PKIX1-PSS-OAEP-Algorithms-2009
   { iso(1) identified-organization(3) dod(6) internet(1)
     security(5) mechanisms(5) pkix(7) id-mod(0)
     id-mod-pkix1-rsa-pkalgs-02(54) }

-- FROM [CMS-ASN]

KEY-WRAP, SIGNATURE-ALGORITHM, DIGEST-ALGORITHM, ALGORITHM,
PUBLIC-KEY, MAC-ALGORITHM, CONTENT-ENCRYPTION, KEY-AGREE, SMIME-CAPS,
AlgorithmIdentifier{}
 FROM AlgorithmInformation-2009
   { iso(1) identified-organization(3) dod(6) internet(1)
     security(5) mechanisms(5) pkix(7) id-mod(0)
     id-mod-algorithmInformation-02(58) }

-- From [CMS-ASN]

OriginatorPublicKey, UserKeyingMaterial
 FROM CryptographicMessageSyntax-2009
   { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
     smime(16) modules(0) id-mod-cms-2004-02(41) }



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RFC 5753              Use of ECC Algorithms in CMS          January 2010


-- From [CMS-ASN]

maca-hMAC-SHA1, cea-3DES-cbc, kwa-3DESWrap, CBCParameter
 FROM CryptographicMessageSyntaxAlgorithms-2009
   { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
     smime(16) modules(0) id-mod-cmsalg-2001-02(37) }

-- From [CMS-ASN]

cea-aes128-cbc, cea-aes192-cbc, cea-aes256-cbc, kwa-aes128-wrap,
kwa-aes192-wrap, kwa-aes256-wrap
 FROM CMSAesRsaesOaep-2009
   { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
     smime(16) modules(0) id-mod-cms-aes-02(38) }

-- From [CMS-ASN]

cea-aes128-CCM, cea-aes192-CCM, cea-aes256-CCM, cea-aes128-GCM,
cea-aes192-GCM, cea-aes256-GCM
 FROM CMS-AES-CCM-and-AES-GCM-2009
   { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
     smime(16) modules(0) id-mod-cms-aes-ccm-gcm-02(44) }

;

-- Constrains the SignedData digestAlgorithms field
-- Constrains the SignedData SignerInfo digestAlgorithm field
-- Constrains the AuthenticatedData digestAlgorithm field

-- Message Digest Algorithms: Imported from [PKI-ASN]

-- MessageDigestAlgs DIGEST-ALGORITHM ::= {
--  mda-sha1   |
--  mda-sha224 |
--  mda-sha256 |
--  mda-sha384 |
--  mda-sha512,
--  ...
-- }

-- Constrains the SignedData SignerInfo signatureAlgorithm field

-- Signature Algorithms: Imported from [PKI-ASN]

-- SignatureAlgs SIGNATURE-ALGORITHM ::= {
--  sa-ecdsaWithSHA1   |
--  sa-ecdsaWithSHA224 |
--  sa-ecdsaWithSHA256 |



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RFC 5753              Use of ECC Algorithms in CMS          January 2010


--  sa-ecdsaWithSHA384 |
--  sa-ecdsaWithSHA512,
--  ...
-- }

-- ECDSA Signature Value: Imported from [PKI-ALG]
-- Contents of SignatureValue OCTET STRING

-- ECDSA-Sig-Value ::= SEQUENCE {
--   r  INTEGER,
--   s  INTEGER
-- }

--
-- Key Agreement Algorithms
--

-- Constrains the EnvelopedData RecipientInfo KeyAgreeRecipientInfo
--   keyEncryption Algorithm field
-- Constrains the AuthenticatedData RecipientInfo
--   KeyAgreeRecipientInfo keyEncryption Algorithm field
-- Constrains the AuthEnvelopedData RecipientInfo
--   KeyAgreeRecipientInfo keyEncryption Algorithm field

-- DH variants are not used with AuthenticatedData or
-- AuthEnvelopedData

KeyAgreementAlgs KEY-AGREE ::= {
 kaa-dhSinglePass-stdDH-sha1kdf-scheme        |
 kaa-dhSinglePass-stdDH-sha224kdf-scheme      |
 kaa-dhSinglePass-stdDH-sha256kdf-scheme      |
 kaa-dhSinglePass-stdDH-sha384kdf-scheme      |
 kaa-dhSinglePass-stdDH-sha512kdf-scheme      |
 kaa-dhSinglePass-cofactorDH-sha1kdf-scheme   |
 kaa-dhSinglePass-cofactorDH-sha224kdf-scheme |
 kaa-dhSinglePass-cofactorDH-sha256kdf-scheme |
 kaa-dhSinglePass-cofactorDH-sha384kdf-scheme |
 kaa-dhSinglePass-cofactorDH-sha512kdf-scheme |
 kaa-mqvSinglePass-sha1kdf-scheme             |
 kaa-mqvSinglePass-sha224kdf-scheme           |
 kaa-mqvSinglePass-sha256kdf-scheme           |
 kaa-mqvSinglePass-sha384kdf-scheme           |
 kaa-mqvSinglePass-sha512kdf-scheme,
 ...
}






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x9-63-scheme OBJECT IDENTIFIER ::= {
 iso(1) identified-organization(3) tc68(133) country(16) x9(840)
 x9-63(63) schemes(0) }

secg-scheme OBJECT IDENTIFIER ::= {
 iso(1) identified-organization(3) certicom(132) schemes(1) }

--
-- Diffie-Hellman Single Pass, Standard, with KDFs
--

-- Parameters are always present and indicate the Key Wrap Algorithm

kaa-dhSinglePass-stdDH-sha1kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-stdDH-sha1kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-stdDH-sha1kdf-scheme
}

dhSinglePass-stdDH-sha1kdf-scheme OBJECT IDENTIFIER ::= {
 x9-63-scheme 2 }

kaa-dhSinglePass-stdDH-sha224kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-stdDH-sha224kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-stdDH-sha224kdf-scheme
}

dhSinglePass-stdDH-sha224kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 11 0 }

kaa-dhSinglePass-stdDH-sha256kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-stdDH-sha256kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-stdDH-sha256kdf-scheme
}

dhSinglePass-stdDH-sha256kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 11 1 }









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kaa-dhSinglePass-stdDH-sha384kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-stdDH-sha384kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-stdDH-sha384kdf-scheme
}

dhSinglePass-stdDH-sha384kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 11 2 }

kaa-dhSinglePass-stdDH-sha512kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-stdDH-sha512kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-stdDH-sha512kdf-scheme
}

dhSinglePass-stdDH-sha512kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 11 3 }

--
-- Diffie-Hellman Single Pass, Cofactor, with KDFs
--

kaa-dhSinglePass-cofactorDH-sha1kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-cofactorDH-sha1kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-cofactorDH-sha1kdf-scheme
}

dhSinglePass-cofactorDH-sha1kdf-scheme OBJECT IDENTIFIER ::= {
 x9-63-scheme 3 }

kaa-dhSinglePass-cofactorDH-sha224kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-cofactorDH-sha224kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-cofactorDH-sha224kdf-scheme
}

dhSinglePass-cofactorDH-sha224kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 14 0 }








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kaa-dhSinglePass-cofactorDH-sha256kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-cofactorDH-sha256kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-cofactorDH-sha256kdf-scheme
}

dhSinglePass-cofactorDH-sha256kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 14 1 }

kaa-dhSinglePass-cofactorDH-sha384kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-cofactorDH-sha384kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-cofactorDH-sha384kdf-scheme
}

dhSinglePass-cofactorDH-sha384kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 14 2 }

kaa-dhSinglePass-cofactorDH-sha512kdf-scheme KEY-AGREE ::= {
 IDENTIFIER dhSinglePass-cofactorDH-sha512kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-dhSinglePass-cofactorDH-sha512kdf-scheme
}

dhSinglePass-cofactorDH-sha512kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 14 3 }

--
-- MQV Single Pass, Cofactor, with KDFs
--

kaa-mqvSinglePass-sha1kdf-scheme KEY-AGREE ::= {
 IDENTIFIER mqvSinglePass-sha1kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-mqvSinglePass-sha1kdf-scheme
}

mqvSinglePass-sha1kdf-scheme OBJECT IDENTIFIER ::= {
 x9-63-scheme 16 }








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kaa-mqvSinglePass-sha224kdf-scheme KEY-AGREE ::= {
 IDENTIFIER mqvSinglePass-sha224kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-mqvSinglePass-sha224kdf-scheme
}

mqvSinglePass-sha224kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 15 0 }

kaa-mqvSinglePass-sha256kdf-scheme KEY-AGREE ::= {
 IDENTIFIER mqvSinglePass-sha256kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-mqvSinglePass-sha256kdf-scheme
}

mqvSinglePass-sha256kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 15 1 }

kaa-mqvSinglePass-sha384kdf-scheme KEY-AGREE ::= {
 IDENTIFIER mqvSinglePass-sha384kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-mqvSinglePass-sha384kdf-scheme
}

mqvSinglePass-sha384kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 15 2 }

kaa-mqvSinglePass-sha512kdf-scheme KEY-AGREE ::= {
 IDENTIFIER mqvSinglePass-sha512kdf-scheme
 PARAMS TYPE KeyWrapAlgorithm ARE required
 UKM -- TYPE unencoded data -- ARE preferredPresent
 SMIME-CAPS cap-kaa-mqvSinglePass-sha512kdf-scheme
}

mqvSinglePass-sha512kdf-scheme OBJECT IDENTIFIER ::= {
 secg-scheme 15 3 }

--
-- Key Wrap Algorithms: Imported from [CMS-ASN]
--








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KeyWrapAlgorithm ::= AlgorithmIdentifier { KEY-WRAP, { KeyWrapAlgs } }

KeyWrapAlgs KEY-WRAP ::= {
 kwa-3DESWrap    |
 kwa-aes128-wrap |
 kwa-aes192-wrap |
 kwa-aes256-wrap,
 ...
}

--
-- Content Encryption Algorithms: Imported from [CMS-ASN]
--

-- Constrains the EnvelopedData EncryptedContentInfo encryptedContent
-- field and the AuthEnvelopedData EncryptedContentInfo
-- contentEncryptionAlgorithm field

-- ContentEncryptionAlgs CONTENT-ENCRYPTION ::= {
--   cea-3DES-cbc |
--   cea-aes128-cbc   |
--   cea-aes192-cbc   |
--   cea-aes256-cbc   |
--   cea-aes128-ccm   |
--   cea-aes192-ccm   |
--   cea-aes256-ccm   |
--   cea-aes128-gcm   |
--   cea-aes192-gcm   |
--   cea-aes256-gcm,
--   ...
--   }

-- des-ede3-cbc and aes*-cbc are used with EnvelopedData and
-- EncryptedData
-- aes*-ccm are used with AuthEnvelopedData
-- aes*-gcm are used with AuthEnvelopedData
-- (where * is 128, 192, and 256)

--
-- Message Authentication Code Algorithms
--

-- Constrains the AuthenticatedData
-- MessageAuthenticationCodeAlgorithm field
--






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MessageAuthAlgs MAC-ALGORITHM ::= {
--  maca-hMAC-SHA1 |
 maca-hMAC-SHA224 |
 maca-hMAC-SHA256 |
 maca-hMAC-SHA384 |
 maca-hMAC-SHA512,
 ...
}

maca-hMAC-SHA224 MAC-ALGORITHM ::= {
 IDENTIFIER id-hmacWithSHA224
 PARAMS ARE absent
 IS-KEYED-MAC TRUE
 SMIME-CAPS cap-hMAC-SHA224
}

id-hmacWithSHA224 OBJECT IDENTIFIER ::= {
 iso(1) member-body(2) us(840) rsadsi(113549)
 digestAlgorithm(2) 8 }

maca-hMAC-SHA256 MAC-ALGORITHM ::= {
 IDENTIFIER id-hmacWithSHA256
 PARAMS ARE absent
 IS-KEYED-MAC TRUE
 SMIME-CAPS cap-hMAC-SHA256
}

id-hmacWithSHA256 OBJECT IDENTIFIER ::= {
 iso(1) member-body(2) us(840) rsadsi(113549)
 digestAlgorithm(2) 9 }

maca-hMAC-SHA384 MAC-ALGORITHM ::= {
 IDENTIFIER id-hmacWithSHA384
 PARAMS ARE absent
 IS-KEYED-MAC TRUE
 SMIME-CAPS cap-hMAC-SHA384
}

id-hmacWithSHA384 OBJECT IDENTIFIER ::= {
 iso(1) member-body(2) us(840) rsadsi(113549)
 digestAlgorithm(2) 10 }

maca-hMAC-SHA512 MAC-ALGORITHM ::= {
 IDENTIFIER id-hmacWithSHA512
 PARAMS ARE absent
 IS-KEYED-MAC TRUE
 SMIME-CAPS cap-hMAC-SHA512
}



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id-hmacWithSHA512 OBJECT IDENTIFIER ::= {
 iso(1) member-body(2) us(840) rsadsi(113549)
 digestAlgorithm(2) 11 }

--
-- Originator Public Key Algorithms
--

-- Constraints on KeyAgreeRecipientInfo OriginatorIdentifierOrKey
-- OriginatorPublicKey algorithm field

OriginatorPKAlgorithms PUBLIC-KEY ::= {
 opka-ec,
 ...
}

opka-ec PUBLIC-KEY ::={
 IDENTIFIER id-ecPublicKey
 KEY ECPoint
 PARAMS TYPE CHOICE { n NULL, p ECParameters } ARE preferredAbsent
}

-- Format for both ephemeral and static public keys: Imported from
-- [PKI-ALG]

-- ECPoint ::= OCTET STRING

-- ECParameters ::= CHOICE {
--   namedCurve      CURVE.&id({NamedCurve})
--   commented out in [PKI-ALG] implicitCurve   NULL
--   commented out in [PKI-ALG] specifiedCurve  SpecifiedECDomain
--   commented out in [PKI-ALG] ...
-- }
 -- implicitCurve and specifiedCurve MUST NOT be used in PKIX.
 -- Details for SpecifiedECDomain can be found in [X9.62].
 -- Any future additions to this CHOICE should be coordinated
 -- with ANSI X.9.

-- Format of KeyAgreeRecipientInfo ukm field when used with
-- ECMQV

MQVuserKeyingMaterial ::= SEQUENCE {
 ephemeralPublicKey       OriginatorPublicKey,
 addedukm             [0] EXPLICIT UserKeyingMaterial OPTIONAL
}






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-- 'SharedInfo' for input to KDF when using ECDH and ECMQV with
-- EnvelopedData, AuthenticatedData, or AuthEnvelopedData

ECC-CMS-SharedInfo ::= SEQUENCE {
 keyInfo         KeyWrapAlgorithm,
 entityUInfo [0] EXPLICIT OCTET STRING OPTIONAL,
 suppPubInfo [2] EXPLICIT OCTET STRING
}

--
-- S/MIME CAPS for algorithms in this document
--







































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SMimeCAPS SMIME-CAPS ::= {
--  mda-sha1.&smimeCaps                                   |
--  mda-sha224.&smimeCaps                                 |
--  mda-sha256.&smimeCaps                                 |
--  mda-sha384.&smimeCaps                                 |
--  mda-sha512.&smimeCaps                                 |
--  sa-ecdsaWithSHA1.&smimeCaps                           |
--  sa-ecdsaWithSHA224.&smimeCaps                         |
--  sa-ecdsaWithSHA256.&smimeCaps                         |
--  sa-ecdsaWithSHA384.&smimeCaps                         |
--  sa-ecdsaWithSHA512.&smimeCaps                         |
 kaa-dhSinglePass-stdDH-sha1kdf-scheme.&smimeCaps        |
 kaa-dhSinglePass-stdDH-sha224kdf-scheme.&smimeCaps      |
 kaa-dhSinglePass-stdDH-sha256kdf-scheme.&smimeCaps      |
 kaa-dhSinglePass-stdDH-sha384kdf-scheme.&smimeCaps      |
 kaa-dhSinglePass-stdDH-sha512kdf-scheme.&smimeCaps      |
 kaa-dhSinglePass-cofactorDH-sha1kdf-scheme.&smimeCaps   |
 kaa-dhSinglePass-cofactorDH-sha224kdf-scheme.&smimeCaps |
 kaa-dhSinglePass-cofactorDH-sha256kdf-scheme.&smimeCaps |
 kaa-dhSinglePass-cofactorDH-sha384kdf-scheme.&smimeCaps |
 kaa-dhSinglePass-cofactorDH-sha512kdf-scheme.&smimeCaps |
 kaa-mqvSinglePass-sha1kdf-scheme.&smimeCaps             |
 kaa-mqvSinglePass-sha224kdf-scheme.&smimeCaps           |
 kaa-mqvSinglePass-sha256kdf-scheme.&smimeCaps           |
 kaa-mqvSinglePass-sha384kdf-scheme.&smimeCaps           |
 kaa-mqvSinglePass-sha512kdf-scheme.&smimeCaps           |
--  kwa-3des.&smimeCaps                                   |
--  kwa-aes128.&smimeCaps                                 |
--  kwa-aes192.&smimeCaps                                 |
--  kwa-aes256.&smimeCaps                                 |
--  cea-3DES-cbc.&smimeCaps                               |
--  cea-aes128-cbc.&smimeCaps                             |
--  cea-aes192-cbc.&smimeCaps                             |
--  cea-aes256-cbc.&smimeCaps                             |
--  cea-aes128-ccm.&smimeCaps                             |
--  cea-aes192-ccm.&smimeCaps                             |
--  cea-aes256-ccm.&smimeCaps                             |
--  cea-aes128-gcm.&smimeCaps                             |
--  cea-aes192-gcm.&smimeCaps                             |
--  cea-aes256-gcm.&smimeCaps                             |
--  maca-hMAC-SHA1.&smimeCaps                             |
 maca-hMAC-SHA224.&smimeCaps                             |
 maca-hMAC-SHA256.&smimeCaps                             |
 maca-hMAC-SHA384.&smimeCaps                             |
 maca-hMAC-SHA512.&smimeCaps,
 ...
}




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cap-kaa-dhSinglePass-stdDH-sha1kdf-scheme SMIME-CAPS ::= {
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-stdDH-sha1kdf-scheme
}

cap-kaa-dhSinglePass-stdDH-sha224kdf-scheme SMIME-CAPS ::= {
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-stdDH-sha224kdf-scheme
}

cap-kaa-dhSinglePass-stdDH-sha256kdf-scheme SMIME-CAPS ::= {
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-stdDH-sha256kdf-scheme
}

cap-kaa-dhSinglePass-stdDH-sha384kdf-scheme SMIME-CAPS ::= {
  TYPE KeyWrapAlgorithm
  IDENTIFIED BY dhSinglePass-stdDH-sha384kdf-scheme
}

cap-kaa-dhSinglePass-stdDH-sha512kdf-scheme SMIME-CAPS ::= {
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-stdDH-sha512kdf-scheme
}

cap-kaa-dhSinglePass-cofactorDH-sha1kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-cofactorDH-sha1kdf-scheme
}

cap-kaa-dhSinglePass-cofactorDH-sha224kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-cofactorDH-sha224kdf-scheme
}

cap-kaa-dhSinglePass-cofactorDH-sha256kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-cofactorDH-sha256kdf-scheme
}

cap-kaa-dhSinglePass-cofactorDH-sha384kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-cofactorDH-sha384kdf-scheme
}







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cap-kaa-dhSinglePass-cofactorDH-sha512kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY dhSinglePass-cofactorDH-sha512kdf-scheme
}

cap-kaa-mqvSinglePass-sha1kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY mqvSinglePass-sha1kdf-scheme
}

cap-kaa-mqvSinglePass-sha224kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY mqvSinglePass-sha224kdf-scheme
}

cap-kaa-mqvSinglePass-sha256kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY mqvSinglePass-sha256kdf-scheme
}

cap-kaa-mqvSinglePass-sha384kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY mqvSinglePass-sha384kdf-scheme
}

cap-kaa-mqvSinglePass-sha512kdf-scheme SMIME-CAPS ::={
 TYPE KeyWrapAlgorithm
 IDENTIFIED BY mqvSinglePass-sha512kdf-scheme
}

cap-hMAC-SHA224 SMIME-CAPS ::={ IDENTIFIED BY id-hmacWithSHA224 }

cap-hMAC-SHA256 SMIME-CAPS ::={ IDENTIFIED BY id-hmacWithSHA256 }

cap-hMAC-SHA384 SMIME-CAPS ::={ IDENTIFIED BY id-hmacWithSHA384 }

cap-hMAC-SHA512 SMIME-CAPS ::={ IDENTIFIED BY id-hmacWithSHA512 }

END












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Appendix B.  Changes since RFC 3278

  The following summarizes the changes:

  - Abstract: The basis of the document was changed to refer to NIST
    FIPS 186-3 and SP800-56A.  However, to maintain backwards
    compatibility the Key Derivation Function from ANSI/SEC1 is
    retained.

  - Section 1: A bullet was added to address AuthEnvelopedData.

  - Section 2.1: A sentence was added to indicate FIPS180-3 is used
    with ECDSA.  Replaced reference to ANSI X9.62 with FIPS186-3.

  - Section 2.1.1: The permitted digest algorithms were expanded from
    SHA-1 to SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512.

  - Section 2.1.2 and 2.1.3: The bullet addressing integer "e" was
    deleted.

  - Section 3: Added explanation of why static-static ECDH is not
    included.

  - Section 3.1: The reference for DH was changed from RFC 3852 to RFC
    3370.  Provided text to indicate fields of EnvelopedData are as in
    CMS.

  - Section 3.1.1: The text was updated to include description of all
    KeyAgreeRecipientInfo fields.  Parameters for id-ecPublicKey field
    changed from NULL to absent or ECParameter.  Additional information
    about ukm was added.

  - Section 3.2: The sentence describing the advantages of 1-Pass ECMQV
    was rewritten.

  - Section 3.2.1: The text was updated to include description of all
    fields.  Parameters for id-ecPublicKey field changed from NULL to
    absent or ECParameters.

  - Sections 3.2.2 and 4.1.2: The re-use of ephemeral keys paragraph
    was reworded.

  - Section 4.1:  The sentences describing the advantages of 1-Pass
    ECMQV was moved to Section 4.

  - Section 4.1.2: The note about the attack was moved to Section 4.





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  - Section 4.2: This section was added to address AuthEnvelopedData
    with ECMQV.

  - Section 5: This section was moved to Section 8.  The 1st paragraph
    was modified to recommend both SignedData and EnvelopedData.  The
    requirements were updated for hash algorithms and recommendations
    for matching curves and hash algorithms.  Also, the requirements
    were expanded to indicate which ECDH and ECMQV variants, key wrap
    algorithms, and content encryption algorithms are required for each
    of the content types used in this document.  The permitted digest
    algorithms used in KDFs were expanded from SHA-1 to SHA-1, SHA-224,
    SHA-256, SHA-384, and SHA-512.

  - Section 6 (formerly 7): This section was updated to allow for
    SMIMECapabilities to be present in certificates.  The S/MIME
    capabilities for ECDSA with SHA-224, SHA-256, SHA-384, and SHA-512
    were added to the list of S/MIME Capabilities.  Also, updated to
    include S/MIME capabilities for ECDH and ECMQV using the SHA-224,
    SHA-256, SHA-384, and SHA-512 algorithms as the KDF.

  - Section 7.1 (formerly 8.1): Added sub-sections for digest,
    signature, originator public key, key agreement, content
    encryption, key wrap, and message authentication code algorithms.
    Pointed to algorithms and parameters in appropriate documents for:
    SHA-224, SHA-256, SHA-384, and SHA-512 as well as SHA-224, SHA-256,
    SHA-384, and SHA-512 with ECDSA.  Also, added algorithm identifiers
    for ECDH std, ECDH cofactor, and ECMQV with SHA-224, SHA-256,
    SHA-384, and SHA-512 algorithms as the KDF.  Changed id-ecPublicKey
    parameters to be absent, NULL, or ECParameters, and if present the
    originator's ECParameters must match the recipient's ECParameters.

  - Section 7.2 (formerly 8.2): Updated to include AuthEnvelopedData.
    Also, added text to address support requirement for compressed,
    uncompressed, and hybrid keys; changed pointers from ANSI X9.61 to
    PKIX (where ECDSA-Sig-Value is imported); changed pointers from
    SECG to NIST specs; and updated example of suppPubInfo to be
    AES-256.  keyInfo's parameters changed from NULL to any associated
    parameters (AES wraps have absent parameters).

  - Section 9: Replaced text, which was a summary paragraph, with an
    updated security considerations section.  Paragraph referring to
    definitions of SHA-224, SHA-256, SHA-384, and SHA-512 is deleted.

  - Updated references.

  - Added ASN.1 modules.

  - Updated acknowledgements section.



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RFC 5753              Use of ECC Algorithms in CMS          January 2010


Acknowledgements

  The methods described in this document are based on work done by the
  ANSI X9F1 working group.  The authors wish to extend their thanks to
  ANSI X9F1 for their assistance.  The authors also wish to thank Peter
  de Rooij for his patient assistance.  The technical comments of
  Francois Rousseau were valuable contributions.

  Many thanks go out to the other authors of RFC 3278: Simon Blake-
  Wilson and Paul Lambert.  Without RFC 3278, this version wouldn't
  exist.

  The authors also wish to thank Alfred Hoenes, Jonathan Herzog, Paul
  Hoffman, Russ Housley, and Jim Schaad for their valuable input.

Authors' Addresses

  Sean Turner
  IECA, Inc.
  3057 Nutley Street, Suite 106
  Fairfax, VA 22031
  USA

  EMail: [email protected]


  Daniel R. L. Brown
  Certicom Corp
  5520 Explorer Drive #400
  Mississauga, ON L4W 5L1
  Canada

  EMail: [email protected]


















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