 1/draftietfsmimecmsrsakem01.txt 20060324 01:12:39.000000000 +0100
+++ 2/draftietfsmimecmsrsakem02.txt 20060324 01:12:39.000000000 +0100
@@ 1,52 +1,70 @@
S/MIME Working Group B. Kaliski
+S/MIME Working Group B.Kaliski/J.Randall
Internet Draft RSA Laboratories
Document: draftietfsmimecmsrsakem01.txt October 2003
+Document: draftietfsmimecmsrsakem02.txt March 2006
Category: Standards
Use of the RSAKEM Key Transport Algorithm in CMS

+
Status of this Memo
 This document is an InternetDraft and is subject to all provisions
 of Section 10 of RFC2026.

InternetDrafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet
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 InternetDrafts are draft documents valid for a maximum of six
 months and may be updated, replaced, or obsoleted by other documents
 at any time. It is inappropriate to use InternetDrafts as
 reference material or to cite them other than as "work in progress."
+ By submitting this InternetDraft, each author represents that any
+ applicable patent or other IPR claims of which he or she is aware
+ have been or will be disclosed, and any of which he or she becomes
+ aware will be disclosed, in accordance with Section 6 of BCP 79.
 The list of current InternetDrafts can be accessed at
+ Copyright (C) The Internet Society (2006).
+
+ This document is subject to the rights, licenses and restrictions
+ contained in BCP 78, and except as set forth therein, the authors
+ retain all their rights.
+
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+
+ InternetDrafts are working documents of the Internet Engineering Task
+ Force (IETF), its areas, and its working groups. Note that other
+ groups may also distribute working documents as InternetDrafts.
+ InternetDrafts are draft documents valid for a maximum of six months
+ and may be updated, replaced, or obsoleted by other documents at any
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Comments or suggestions for improvement may be made on the "ietf
smime" mailing list, or directly to the author.
Abstract
The RSAKEM Key Transport Algorithm is a onepass (storeandforward)
mechanism for transporting keying data to a recipient using the
recipient's RSA public key. This document specifies the conventions
for using the RSAKEM Key Transport Algorithm with the Cryptographic
 Message Syntax (CMS). This version (01) updates the ASN.1 syntax to
 align with the latest drafts of ANS X9.44 and ISO/IEC 180332, and
 adds material on certificate conventions and S/MIME capabilities.
+ Message Syntax (CMS). This version (02) updates the ASN.1 syntax to
+ align with the latest draft of ANS X9.44 and ISO/IEC 180332, and
+ adds material on Camillia algorirthm.
Conventions Used in This Document
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 RFC 2119
[STDWORDS].
1. Introduction
@@ 89,25 +107,24 @@
of the message, and the keyencrypting key KEK is derived from it in
a strong way. As a result, the algorithm enjoys a "tight" security
proof in the random oracle model. It is also architecturally
convenient because the publickey operations are separate from the
symmetric operations on the keying data. One benefit is that the
length of the keying data is bounded only by the symmetric key
wrapping scheme, not the size of the RSA modulus.
The RSAKEM Key Transport Algorithm in various forms is being adopted
in several draft standards including the draft ANS X9.44 [ANSX9.44]
 and the draft ISO/IEC 180332 [ISOIEC180332]. It has also been
 recommended by the NESSIE project [NESSIE]. Although the other
 standards are still in development, the algorithm is stable across
 the drafts. For completeness, a specification of the algorithm is
 given in Appendix A of this document; ASN.1 syntax is given in
+ and ISO/IEC 180332. It has also been recommended by the NESSIE
+ project [NESSIE]. For completeness, a specification of the algorithm
+
+ is given in Appendix A of this document; ASN.1 syntax is given in
Appendix B.
NOTE: The term KEM stands for "key encapsulation mechanism" and
refers to the first three steps of the process above. The
formalization of key transport algorithms (or more generally,
asymmetric encryption schemes) in terms of key encapsulation
mechanisms is described further in research by Victor Shoup leading
to the development of the ISO/IEC 180332 standard [SHOUP].
2. Use in CMS
@@ 125,46 +142,52 @@
has also been proposed as a replacement (see [PKCS1] and [CMS
OAEP]). RSAKEM has the advantage over RSAESOAEP of a tighter
security proof, but the disadvantage of slightly longer encrypted
keying data.
2.1 Underlying Components
A CMS implementation that supports the RSAKEM Key Transport
Algorithm MUST support at least the following underlying components:
 * For the key derivation function, KDF2 (see [ANSX9.44][IEEE
 P1363a]) based on SHA1 (see [FIPS1802]) (this function is
 also specified as the key derivation function in [ANSX9.63])
+ * For the key derivation function, KDF2 or KDF3 (see [ANSX9.44]
+ [IEEEP1363a]) based on SHA1 (see [FIPS1802]) (this function
+ is also specified as the key derivation function in [ANSX9.63])
* For the keywrapping scheme, AESWrap128, i.e., the AES Key
Wrap with a 128bit key encrypting key (see [AESWRAP])
 An implementation SHOULD also support KDF2 based on SHA256 (see
 [FIPS1802]), and the TripleDES Key Wrap (see [3DESWRAP]). It MAY
 support other underlying components.
+ An implementation SHOULD also support KDF2 and KDF3 based on SHA256
+ (see [FIPS1802]), the TripleDES Key Wrap (see [3DESWRAP]) and the
+ Camillia key wrap algorithm (see [Camillia]). It MAY support other
+ underlying components. When AES or Camilla are used the data block
+ size is 128 bits while the key size can be 128, 192, or 256 bits
+ while Triple DES requires a data block size of 64 bits and a key size
+ of 112 or 168 bits.
2.2 RecipientInfo Conventions
When the RSAKEM Key Transport Algorithm is employed for a recipient,
 recipient, the RecipientInfo alternative for that recipient MUST be
+ the RecipientInfo alternative for that recipient MUST be
KeyTransRecipientInfo. The algorithmspecific fields of the
KeyTransRecipientInfo value MUST have the following values:
* keyEncryptionAlgorithm.algorithm MUST be idacgenerichybrid
(see Appendix B)
+
* keyEncryptionAlgorithm.parameters MUST be a value of type
GenericHybridParameters, identifying the RSAKEM key
encapsulation mechanism (see Appendix B)
* encryptedKey MUST be the encrypted keying data output by the
 algorithm (see Appendix A)
+ algorithm, where the keying data is the contentencryption key.
+ (see Appendix A)
2.3 Certificate Conventions
The conventions specified in this section augment RFC 3280 [PROFILE].
A recipient who employs the RSAKEM Key Transport Algorithm MAY
identify the public key in a certificate by the same
AlgorithmIdentifier as for the PKCS #1 v1.5 algorithm, i.e., using
the rsaEncryption object identifier [PKCS1].
@@ 195,21 +218,25 @@
usage certificate extension (see [PROFILE], Section 4.2.1.3). If the
keyUsage extension is present in a certificate that conveys an RSA
public key with the idacgenerichybrid object identifier as
discussed above, then the key usage extension MUST contain the
following value:
keyEncipherment.
dataEncipherment SHOULD NOT be present. That is, a key intended to be
employed only with the RSAKEM Key Transport Algorithm SHOULD NOT
 also be employed for data encryption.
+ also be employed for data encryption or for authentication such as in
+ signatures. Good cryptographic practice employs a given RSA key pair
+ in only one scheme. This practice avoids the risk that vulnerability
+ in one scheme may compromise the security of the other, and may be
+ essential to maintain provable security.
2.4 SMIMECapabilities Attribute Conventions
RFC 2633 [MSG], Section 2.5.2 defines the SMIMECapabilities signed
attribute (defined as a SEQUENCE of SMIMECapability SEQUENCEs) to be
used to specify a partial list of algorithms that the software
announcing the SMIMECapabilities can support. When constructing a
signedData object, compliant software MAY include the
SMIMECapabilities signed attribute announcing that it supports the
RSAKEM Key Transport algorithm.
@@ 235,40 +262,41 @@
encapsulation mechanism [SHOUP]. While in practice a randomoracle
result does not provide an actual security proof for any particular
key derivation function, the result does provide assurance that the
general construction is reasonable; a key derivation function would
need to be particularly weak to lead to an attack that is not
possible in the random oracle model.
The RSA key size and the underlying components should be selected
consistent with the desired symmetric security level for an
application. Several security levels have been identified in [NIST
 GUIDELINE]. For brevity, the first three levels are mentioned here:
+ FIPS PUB 80057]. For brevity, the first three levels are mentioned
+ here:
* 80bit security. The RSA key size SHOULD be at least 1024 bits,
 the hash function underlying KDF2 SHOULD be SHA1 or above, and
 the symmetric keywrapping scheme SHOULD be AES Key Wrap or
 TripleDES Key Wrap.
+ the hash function underlying the KDF SHOULD be SHA1 or above,
+ and the symmetric keywrapping scheme SHOULD be AES Key Wrap,
+ TripleDES Key Wrap, or Camillia Key Wrap.
* 112bit security. The RSA key size SHOULD be at least 2048
 bits, the hash function underlying KDF2 SHOULD be SHA224 or
+ bits, the hash function underlying the KDF SHOULD be SHA224 or
above, and the symmetric keywrapping scheme SHOULD be AES Key
 Wrap or TripleDES Key Wrap.
+ Wrap, TripleDES Key Wrap, or Camillia Key Wrap.
* 128bit security. The RSA key size SHOULD be at least 3072
 bits, the hash function underlying KDF2 SHOULD be SHA256 or
+ bits, the hash function underlying the KDF SHOULD be SHA256 or
above, and the symmetric keywrapping scheme SHOULD be AES Key
 Wrap.
+ Wrap or Camillia Key Wrap.
 Note that the AES Key Wrap MAY be used at all three of these levels;
 the use of AES does not require a 128bit security level for other
 components.
+ Note that the AES Key Wrap or Camillia Key Wrap MAY be used at all
+ three of these levels; the use of AES or Camillia does not require a
+ 128bit security level for other components.
Implementations MUST protect the RSA private key and the content
encryption key. Compromise of the RSA private key may result in the
disclosure of all messages protected with that key. Compromise of the
contentencryption key may result in disclosure of the associated
encrypted content.
Additional considerations related to key management may be found in
[NISTGUIDELINE].
@@ 298,40 +326,43 @@
Accordingly, an RSA key pair used for the RSAKEM Key Transport
Algorithm SHOULD NOT also be used for digital signatures. (Indeed,
ASC X9 requires such a separation between key establishment key pairs
and digital signature key pairs.) Continuing this principle of key
separation, a key pair used for the RSAKEM Key Transport Algorithm
SHOULD NOT be used with other key establishment schemes, or for data
encryption, or with more than one set of underlying algorithm
components.
 Parties MAY wish to formalize the assurance that one another's
+ Parties MAY formalize the assurance that one another's
implementations are correct through implementation validation, e.g.
NIST's Cryptographic Module Validation Program (CMVP).
4. References
4.1 Normative References
3DESWRAP Housley, R. TripleDES and RC2 Key Wrapping. RFC
3217. December 2001.
AESWRAP Schaad, J. and R. Housley. Advanced Encryption
Standard (AES) Key Wrap Algorithm. RFC 3394.
September 2002.
ANSX9.63 American National Standard X9.632002: Public Key
Cryptography for the Financial Services Industry:
Key Agreement and Key Transport Using Elliptic
Curve Cryptography.
+ CAMILLIA Kato, A., Moriai, S., and Kanda, M.: The Camellia
+ Cipher Algorithm and Its Use With IPsec. RFC 4312.
+ December 2005
CMS Housley, R. Cryptographic Message Syntax. RFC
3369. August 2002.
CMSALGS Housley, R. Cryptographic Message Syntax (CMS)
Algorithms. RFC 3370. August 2002.
FIPS1802 National Institute of Standards and Technology
(NIST). FIPS 1802: Secure Hash Standard. August
2002.
@@ 344,46 +375,43 @@
Profile. RFC 3280. April 2002.
STDWORDS Bradner, S. Key Words for Use in RFCs to Indicate
Requirement Levels. RFC 2119. March 1997.
4.2 Informative References
ANSX9.44 ASC X9F1 Working Group. Draft American National
Standard X9.44: Public Key Cryptography for the
Financial Services Industry  Key Establishment
 Using Integer Factorization Cryptography. Draft D6,
 October 15, 2003.
+ Using Integer Factorization Cryptography. Draft
+ D11, January 2006.
CMSOAEP Housley, R. Use of the RSAESOAEP Key Transport
Algorithm in the Cryptographic Message Syntax
(CMS). RFC 3560. July 2003.
 IEEEP1363a IEEE P1363 Working Group. IEEE P1363a: Standard
 Specifications for Public Key Cryptography:
 Additional Techniques. Draft D12, May 12, 2003.
 Available via http://grouper.ieee.org/groups/1363.
+ IEEEP1363a IEEE Std 1363a2004: Standard Specifications for
+ Public Key Cryptography: Additional Techniques.
+ IEEE, 2004.
 ISOIEC180332 ISO/IEC 180332: Information technology  Security
 techniques  Encryption algorithms – Part 2:
 Asymmetric Ciphers. 2nd Committee Draft, July 10,
 2003.
+ ISOIEC180332 ISO/IEC 180332:2005 Information technology 
+ Security techniques  Encryption algorithms –
+ Part 2: Asymmetric Ciphers. ISO/IEC, 2005.
NESSIE NESSIE Consortium. Portfolio of Recommended
Cryptographic Primitives. February 27, 2003.
Available via http://www.cryptonessie.org/.
NISTGUIDELINE National Institute of Standards and Technology.
Special Publication 80057: Recommendation for Key
 Management. Part 1: General Guideline. Draft,
 January 2003. Available via
 http://csrc.nist.gov/CryptoToolkit/tkkeymgmt.html.
+ Management. Part 1: General Guideline. August 2005.
+ Available via http://csrc.nist.gov/publications/index.html.
PKCS1 Jonsson, J. and B. Kaliski. PKCS #1: RSA
Cryptography Specifications Version 2.1. RFC 3447.
February 2003.
RANDOM Eastlake, D., S. Crocker, and J. Schiller.
Randomness Recommendations for Security. RFC 1750.
December 1994.
SHOUP Shoup, V. A Proposal for an ISO Standard for
@@ 397,36 +425,37 @@
were assigned in other IETF documents, in ISO/IEC standards
documents, by the National Institute of Standards and Technology
(NIST), and in PublicKey Cryptography Standards (PKCS) documents.
The one exception is that the ASN.1 module's identifier (see Appendix
B.3) is assigned in this document. No further action by the IANA is
necessary for this document or any anticipated updates.
6. Acknowledgments
This document is one part of a strategy to align algorithm standards
 produced by ASC X9, ISO/IEC JTC1 SC27, NIST, and the IETF. I would
+ produced by ASC X9, ISO/IEC JTC1 SC27, NIST, and the IETF. We would
like to thank the members of the ASC X9F1 working group for their
contributions to drafts of ANS X9.44 which led to this specification.
 My thanks as well to Russ Housley as well for his guidance and
 encouragement. I also appreciate the helpful direction I've received
 from Blake Ramsdell and Jim Schaad in bringing this document to
 fruition.
+ Our thanks to Russ Housley as well for his guidance and
+ encouragement. We also appreciate the helpful direction we've
+ received from Blake Ramsdell and Jim Schaad in bringing this document
+ to fruition.
7. Author's Address
+7. Authors' Addresses
+ James Randall
Burt Kaliski
RSA Laboratories
174 Middlesex Turnpike
Bedford, MA 01730
USA
 bkaliski@rsasecurity.com
+ {jrandall, bkaliski}@rsasecurity.com
Appendix A. RSAKEM Key Transport Algorithm
The RSAKEM Key Transport Algorithm is a onepass (storeandforward)
mechanism for transporting keying data to a recipient using the
recipient's RSA public key.
With this type of algorithm, a sender encrypts the keying data using
the recipient's public key to obtain encrypted keying data. The
recipient decrypts the encrypted keying data using the recipient's
@@ 440,32 +469,30 @@
specified length from a shared secret value
* Wrap, a symmetric keywrapping scheme, which encrypts keying
data using a keyencrypting key
In the following, kekLen denotes the length in bytes of the key
encrypting key for the underlying symmetric keywrapping scheme.
In this scheme, the length of the keying data to be transported MUST
be among the lengths supported by the underlying symmetric key
 wrapping scheme. (The AES Key Wrap, for instance, requires the length
 of the keying data to be a multiple of 8 bytes, and at least 16
 bytes.) Usage and formatting of the keying data (e.g., parity
 adjustment for TripleDES keys) is outside the scope of this
 algorithm.

 With some key derivation functions, it is possible to include other
 information besides the shared secret value in the input to the
 function. Also, with some symmetric keywrapping schemes, it is
 possible to associate a label with the keying data. Such uses are
 outside the scope of this document, as they are not directly
 supported by CMS.
+ wrapping scheme. (Bothe the AES and Camillia Key Wraps, for instance,
+ require the length of the keying data to be a multiple of 8 bytes,
+ and at least 16 bytes.) Usage and formatting of the keying data
+ (e.g., parity adjustment for TripleDES keys) is outside the scope of
+ this algorithm. With some key derivation functions, it is possible to
+ include other information besides the shared secret value in the
+ input to the function. Also, with some symmetric keywrapping
+ schemes, it is possible to associate a label with the keying data.
+ Such uses are outside the scope of this document, as they are not
+ directly supported by CMS.
A.2 Sender's Operations
Let (n,e) be the recipient's RSA public key (see [PKCS1] for details)
and let K be the keying data to be transported.
Let nLen denote the length in bytes of the modulus n, i.e., the least
integer such that 2^{8*nLen} > n.
The sender performs the following operations:
@@ 563,25 +588,25 @@
of the implementation SHOULD be the same at these steps for all
ciphertexts C that are in range. (For example, IntegerToString
conversion should take the same amount of time regardless of the
actual value of the integer z.) The integer z, the string Z and other
intermediate results MUST be securely deleted when they are no longer
needed.
Appendix B. ASN.1 Syntax
The ASN.1 syntax for identifying the RSAKEM Key Transport Algorithm
 is an extension of the syntax for the "generic hybrid cipher" in the
 draft ISO/IEC 180332 [ISOIEC180332], and is the same as employed
 in the draft ANS X9.44 [ANSX9.44]. The syntax for the scheme is
 given in Section B.1. The syntax for selected underlying components
 including those mentioned above is given in B.2.
+ is an extension of the syntax for the "generic hybrid cipher" in
+ ISO/IEC 180332 [ISOIEC180332], and is the same as employed in the
+ draft ANS X9.44 [ANSX9.44]. The syntax for the scheme is given in
+ Section B.1. The syntax for selected underlying components including
+ those mentioned above is given in B.2.
The following object identifier prefixes are used in the definitions
below:
is180332 OID ::= { iso(1) standard(0) is18033(18033) part2(2) }
nistAlgorithm OID ::= {
jointisoitut(2) country(16) us(840) organization(1)
gov(101) csor(3) nistAlgorithm(4)
}
@@ 578,32 +603,31 @@
The following object identifier prefixes are used in the definitions
below:
is180332 OID ::= { iso(1) standard(0) is18033(18033) part2(2) }
nistAlgorithm OID ::= {
jointisoitut(2) country(16) us(840) organization(1)
gov(101) csor(3) nistAlgorithm(4)
}

pkcs1 OID ::= {
iso(1) memberbody(2) us(840) rsadsi(113549) pkcs(1) pkcs1(1)
}
NullParms is a more descriptive synonym for NULL when an algorithm
identifier has null parameters:
NullParms ::= NULL
 The material in this Appendix is based on a draft standard and is
 SUBJECT TO CHANGE as that standard is developed.
+ The material in this Appendix is based on a draft standard, ANS
+ X9.44, and is SUBJECT TO CHANGE as that standard is developed.
B.1 RSAKEM Key Transport Algorithm
The object identifier for the RSAKEM Key Transport Algorithm is the
same as for the "generic hybrid cipher" in the draft ANS ISO/IEC
180332, idacgenerichybrid, which is defined in the draft as
idacgenerichybrid OID ::= {
is180332 asymmetriccipher(1) generichybrid(2)
}
@@ 614,103 +638,103 @@
GenericHybridParameters ::= {
kem KeyEncapsulationMechanism,
dem DataEncapsulationMechanism
}
The fields of type GenericHybridParameters have the following
meanings:
* kem identifies the underlying key encapsulation mechanism. For
the RSAKEM Key Transport Algorithm, the scheme is RSAKEM from
 the draft ISO/IEC 180332.
+ ISO/IEC 180332.
The object identifier for RSAKEM (as a key encapsulation
 mechanism) is idkemrsa, which is defined in the draft ISO/IEC
 180332 as
+ mechanism) is idkemrsa, which is defined in ISO/IEC 180332
+ as
idkemrsa OID ::= {
is180332 keyencapsulationmechanism(2) rsa(4)
}
The associated parameters for idkemrsa have type
RsaKemParameters:
RsaKemParameters ::= {
keyDerivationFunction KeyDerivationFunction,
keyLength KeyLength
}
The fields of type RsaKemParameters have the following
meanings:
* keyDerivationFunction identifies the underlying key
derivation function. For alignment with the draft ANS
 X9.44, it MUST be KDF2. However, other key derivation
 functions MAY be used with CMS. Please see B.2.1 for the
 syntax for KDF2.
+ X9.44, it MUST be KDF2 or KDF3. However, other key
+ derivation functions MAY be used with CMS. Please see
+ B.2.1 for the syntax for KDF2 and KDF3.
KeyDerivationFunction ::=
AlgorithmIdentifier {{KDFAlgorithms}}
 KDFAlgorithms ALGORITHMS ::= {
 kdf2,
+ KDFAlgorithms ALGORITHM ::= {
+ kdf2  kdf3,
...  implementations may define other methods
}
* keyLength is the length in bytes of the keyencrypting
key, which depends on the underlying symmetric key
wrapping scheme.

KeyLength ::= INTEGER (1..MAX)
* dem identifies the underlying data encapsulation mechanism.
For alignment with the draft ANS X9.44, it MUST be an X9
approved symmetric keywrapping scheme. (See Note.) However,
other symmetric keywrapping schemes MAY be used with CMS.
 Please see B.2.2 for the syntax for the AES and TripleDES Key
 Wraps.
+ Please see B.2.2 for the syntax for the AES, TripleDES, and
+ Camillia Key Wraps.
DataEncapsulationMechanism ::=
AlgorithmIdentifier {{DEMAlgorithms}}
DEMAlgorithms ALGORITHM ::= {
X9SymmetricKeyWrappingSchemes,
+ CamilliaKeyWrappingSchemes,
...  implementations may define other methods
}
+
X9SymmetricKeyWrappingSchemes ALGORITHM ::= {
aes128Wrap  aes192Wrap  aes256Wrap  tdesWrap,
...  allows for future expansion
}
+ CamilliaKeyWrappingSchemes ALGORITHM ::= {
+ camillia128Wrap  camillia192Wrap  camillia256Wrap
+ }
 NOTE: The generic hybrid cipher in the draft ISO/IEC 180332 can
 encrypt arbitrary data, hence the term "data encapsulation
 mechanism". The symmetric keywrapping schemes take the role of data
 encapsulation mechanisms in the RSAKEM Key Transport Algorithm. The
 draft ISO/IEC 180332 currently allows only three particular data
 encapsulation mechanisms, not including any of these symmetric key
 wrapping schemes. However, the ASN.1 syntax in that document expects
 that additional algorithms will be allowed.
+ NOTE: The generic hybrid cipher in ISO/IEC 180332 can encrypt
+ arbitrary data, hence the term "data encapsulation mechanism". The
+ symmetric keywrapping schemes take the role of data encapsulation
+ mechanisms in the RSAKEM Key Transport Algorithm. ISO/IEC 180332
+ allows only three specific data encapsulation mechanisms, not
+ including any of these symmetric keywrapping schemes. However, the
+ ASN.1 syntax in that document expects that additional algorithms will
+ be allowed.
B.2 Selected Underlying Components
B.2.1 Key Derivation Functions
The object identifier for KDF2 (see [ISOIEC180332]) is
 idkdfkdf2 OID ::= {
 is180332 keyderivationfunctions(5) kdf2(2)
 }

The associated parameters identify the underlying hash function. For
alignment with the draft ANS X9.44, the hash function MUST be an ASC
 X9approved hash function. (See Note.) However, other hash functions
 MAY be used with CMS.
+ X9approved hash function. However, other hash functions MAY be used
+ with CMS.
kdf2 ALGORITHM ::= {{ OID idkdfkdf2 PARMS KDF2HashFunction }}
KDF2HashFunction ::= AlgorithmIdentifier {{KDF2HashFunctions}}
KDF2HashFunctions ALGORITHM ::= {
X9HashFunctions,
...  implementations may define other methods
}
@@ 718,42 +742,58 @@
sha1  sha224  sha256  sha384  sha512,
...  allows for future expansion
}
The object identifier for SHA1 is
idsha1 OID ::= {
iso(1) identifiedorganization(3) oiw(14) secsig(3)
algorithms(2) sha1(26)
}
+ The object identifiers for SHA224, SHA256, SHA384 and SHA512 are
 The object identifiers for SHA256, SHA384 and SHA512 are

+ idsha224 OID ::= { nistAlgorithm hashAlgs(2) sha224(4) }
idsha256 OID ::= { nistAlgorithm hashAlgs(2) sha256(1) }
idsha384 OID ::= { nistAlgorithm hashAlgs(2) sha384(2) }
idsha512 OID ::= { nistAlgorithm hashAlgs(2) sha512(3) }
There has been some confusion over whether the various SHA object
identifiers have a NULL parameter, or no associated parameters. As
also discussed in [PKCS1], implementations SHOULD generate algorithm
identifiers without parameters, and MUST accept algorithm identifiers
either without parameters, or with NULL parameters.
sha1 ALGORITHM ::= {{ OID idsha1 }}  NULLParms MUST be
sha224 ALGORITHM ::= {{ OID idsha224 }}  accepted for these
sha256 ALGORITHM ::= {{ OID idsha256 }}  OIDs
sha384 ALGORITHM ::= {{ OID idsha384 }} – ""
sha512 ALGORITHM ::= {{ OID idsha512 }} – ""
 NOTE: As of this writing, only SHA1 is an ASC X9approved hash
 function; SHA224 and above are in the process of being approved. The
 object identifier for SHA224 has not yet been assigned.
+ The object identifier for KDF3 is:
+
+ idkdfkdf3 OID ::= {
+ to be assigned
+ }
+
+ The associated parameters identify the underlying hash function. For
+ alignment with the draft ANS X9.44, the hash function MUST be an ASC
+ X9approved hash function. (See Note.) However, other hash functions
+ MAY be used with CMS.
+
+ kdf3 ALGORITHM ::= {{ OID idkdfkdf3 PARMS KDF3HashFunction }}
+
+ KDF3HashFunction ::= AlgorithmIdentifier {{KDF3HashFunctions}}
+
+ KDF3HashFunctions ALGORITHM ::= {
+ X9HashFunctions,
+ ...  implementations may define other methods
+ }
B.2.2 Symmetric KeyWrapping Schemes
The object identifiers for the AES Key Wrap depends on the size of
the key encrypting key. There are three object identifiers (see
[AESWRAP]):
idaes128Wrap OID ::= { nistAlgorithm aes(1) aes128Wrap(5) }
idaes192Wrap OID ::= { nistAlgorithm aes(1) aes192Wrap(25) }
idaes256Wrap OID ::= { nistAlgorithm aes(1) aes256Wrap(45) }
@@ 773,20 +812,44 @@
}
This object identifier has a NULL parameter.
tdesWrap ALGORITHM ::=
{{ OID idalgCMS3DESwrap PARMS NullParms }}
NOTE: As of this writing, the AES Key Wrap and the TripleDES Key
Wrap are in the process of being approved by ASC X9.
+ The object identifiers for the Camillia Key Wrap depends on the size of
+ the key encrypting key. There are three object identifiers:
+
+ idcamellia128Wrap OBJECT IDENTIFIER ::=
+ { iso(1) memberbody(2) 392 200011 61 security(1)
+ algorithm(1) keywrapalgorithm(3)
+ camellia128wrap(2) }
+
+ idcamellia192Wrap OBJECT IDENTIFIER ::=
+ { iso(1) memberbody(2) 392 200011 61 security(1)
+ algorithm(1) keywrapalgorithm(3)
+ camellia192wrap(3) }
+
+ idcamellia256Wrap OBJECT IDENTIFIER ::=
+ { iso(1) memberbody(2) 392 200011 61 security(1)
+ algorithm(1) keywrapalgorithm(3)
+ camellia256wrap(4) }
+
+ These object identifiers have no associated parameters.
+
+ camellia128Wrap ALGORITHM ::= {{ OID idcamellia128wrap }}
+ camellia192Wrap ALGORITHM ::= {{ OID idcamellia192wrap }}
+ camellia256Wrap ALGORITHM ::= {{ OID idcamellia256wrap }}
+
B.3 ASN.1 module
CMSRSAKEM
{ iso(1) memberbody(2) us(840) rsadsi(113549) pkcs(1)
pkcs9(9) smime(16) modules(0) cmsrsakem(21) } [[check]]
BEGIN
 EXPORTS ALL
@@ 848,62 +911,79 @@
}
RsaKemParameters ::= {
keyDerivationFunction KeyDerivationFunction,
keyLength KeyLength
}
KeyDerivationFunction ::= AlgorithmIdentifier {{KDFAlgorithms}}
KDFAlgorithms ALGORITHMS ::= {
 kdf2,
+ kdf2  kdf3,
...  implementations may define other methods
}
KeyLength ::= INTEGER (1..MAX)
DataEncapsulationMechanism ::= AlgorithmIdentifier {{DEMAlgorithms}}
DEMAlgorithms ALGORITHM ::= {
X9SymmetricKeyWrappingSchemes,
+ CamilliaKeyWrappingSchemes,
...  implementations may define other methods
}
X9SymmetricKeyWrappingSchemes ALGORITHM ::= {
aes128Wrap  aes192Wrap  aes256Wrap  tdesWrap,
...  allows for future expansion
}
+CamilliaKeyWrappingSchemes ALGORITHM ::= {
+ camillia128Wrap  camillia192Wrap  camillia128Wrap
+ }
 Key Derivation Functions
idkdfkdf2 OID ::= { is180332 keyderivationfunctions(5) kdf2(2) }
kdf2 ALGORITHM ::= {{ OID idkdfkdf2 PARMS KDF2HashFunction }}
KDF2HashFunction ::= AlgorithmIdentifier {{KDF2HashFunctions}}
KDF2HashFunctions ALGORITHM ::= {
X9HashFunctions,
...  implementations may define other methods
}
+
+  idkdfkdf3 OID ::= (to be assigned)
+
+ kdf3 ALGORITHM ::= {{ OID idkdfkdf2 PARMS KDF3HashFunction }}
+
+ KDF3HashFunction ::= AlgorithmIdentifier {{KDF3HashFunctions}}
+
+ KDF3HashFunctions ALGORITHM ::= {
+ X9HashFunctions,
+ ...  implementations may define other methods
+ }
+
 Hash Functions
X9HashFunctions ALGORITHM ::= {
sha1  sha224  sha256  sha384  sha512,
...  allows for future expansion
}
idsha1 OID ::= {
iso(1) identifiedorganization(3) oiw(14) secsig(3)
algorithms(2) sha1(26)
}
+ idsha224 OID ::= { nistAlgorithm hashAlgs(2) sha256(4) }
idsha256 OID ::= { nistAlgorithm hashAlgs(2) sha256(1) }
idsha384 OID ::= { nistAlgorithm hashAlgs(2) sha384(2) }
idsha512 OID ::= { nistAlgorithm hashAlgs(2) sha512(3) }
sha1 ALGORITHM ::= {{ OID idsha1 }}  NullParms MUST be
sha224 ALGORITHM ::= {{ OID idsha224 }}  accepted for these
sha256 ALGORITHM ::= {{ OID idsha256 }}  OIDs
sha384 ALGORITHM ::= {{ OID idsha384 }} – ""
sha512 ALGORITHM ::= {{ OID idsha512 }} – ""
@@ 917,20 +996,39 @@
aes192Wrap ALGORITHM ::= {{ OID idaes192wrap }}
aes256Wrap ALGORITHM ::= {{ OID idaes256wrap }}
idalgCMS3DESwrap OBJECT IDENTIFIER ::= {
iso(1) memberbody(2) us(840) rsadsi(113549) pkcs(1) pkcs9(9)
smime(16) alg(3) 6
}
tdesWrap ALGORITHM ::= {{ OID idalgCMS3DESwrap PARMS NullParms }}
+ idcamellia128Wrap OBJECT IDENTIFIER ::=
+ { iso(1) memberbody(2) 392 200011 61 security(1)
+ algorithm(1) keywrapalgorithm(3)
+ camellia128wrap(2) }
+
+ idcamellia192Wrap OBJECT IDENTIFIER ::=
+ { iso(1) memberbody(2) 392 200011 61 security(1)
+ algorithm(1) keywrapalgorithm(3)
+ camellia192wrap(3) }
+
+ idcamellia256Wrap OBJECT IDENTIFIER ::=
+ { iso(1) memberbody(2) 392 200011 61 security(1)
+ algorithm(1) keywrapalgorithm(3)
+ camellia256wrap(4) }
+
+ camellia128Wrap ALGORITHM ::= {{ OID idcamellia128wrap }}
+ camellia192Wrap ALGORITHM ::= {{ OID idcamellia192wrap }}
+ camellia256Wrap ALGORITHM ::= {{ OID idcamellia256wrap }}
+
B.4 Examples
As an example, if the key derivation function is KDF2 based on
SHA256 and the symmetric keywrapping scheme is the AES Key Wrap
with a 128bit KEK, the AlgorithmIdentifier for the RSAKEM Key
Transport Algorithm will have the following value:
SEQUENCE {
idacgenerichybrid,  generic cipher
SEQUENCE {  GenericHybridParameters
@@ 990,21 +1088,21 @@
30 4f 06 07 28 81 8c 71 02 01 02 30 44 30 21 06
07 28 81 8c 71 02 02 04 30 16 30 12 06 07 28 81
8c 71 02 05 02 30 07 06 05 2b 0e 03 02 1a 02 10
30 0f 06 0b 2a 86 48 86 f7 0d 01 09 10 03 06 05
00
* KDF2 based on SHA224, TripleDES Key Wrap with a 192bit
KEK (threekey tripleDES)
 [[to be defined, awaiting OID for SHA224]]
+ [[to be defined]]
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