Skip to main content

Use of the RSA-KEM Key Transport Algorithm in the Cryptographic Message Syntax (CMS)
RFC 5990

Revision differences

Document history

Date Rev. By Action
2015-10-14
13 (System) Notify list changed from smime-chairs@ietf.org, draft-ietf-smime-cms-rsa-kem@ietf.org to (None)
2012-08-22
13 (System) post-migration administrative database adjustment to the No Objection position for Lars Eggert
2012-08-22
13 (System) post-migration administrative database adjustment to the No Objection position for Russ Housley
2010-09-23
13 Cindy Morgan State changed to RFC Published from RFC Ed Queue by Cindy Morgan
2010-09-23
13 Cindy Morgan [Note]: changed to 'RFC 5990' by Cindy Morgan
2010-09-23
13 (System) RFC published
2010-06-11
13 Amy Vezza State Changes to RFC Ed Queue from Approved-announcement sent by Amy Vezza
2010-06-10
13 (System) IANA Action state changed to No IC from In Progress
2010-06-10
13 (System) IANA Action state changed to In Progress
2010-06-10
13 Cindy Morgan IESG state changed to Approved-announcement sent
2010-06-10
13 Cindy Morgan IESG has approved the document
2010-06-10
13 Cindy Morgan Closed "Approve" ballot
2010-06-08
13 Peter Saint-Andre [Ballot Position Update] New position, No Objection, has been recorded by Peter Saint-Andre
2010-06-08
13 Peter Saint-Andre
[Ballot comment]
1. In Section 1, the text "specified the of different object identifier" is missing a word (I assume "use" between "the" and "of"). …
[Ballot comment]
1. In Section 1, the text "specified the of different object identifier" is missing a word (I assume "use" between "the" and "of").

2. In Section 2.4, this text is potentially confusing:

  The intended application for the key MAY be indicated in the key
  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 id-rsa-kem object identifier as discussed above,
  then the key usage extension MUST contain the following value:

      keyEncipherment.

Is the indented text meant to be "keyEncipherment" (without the period) instead of "keyEncipherment." (with the period)?
2010-06-07
13 Russ Housley [Ballot Position Update] Position for Russ Housley has been changed to No Objection from Discuss by Russ Housley
2010-06-01
13 (System) Sub state has been changed to AD Follow up from New Id Needed
2010-06-01
13 (System) New version available: draft-ietf-smime-cms-rsa-kem-13.txt
2010-05-29
13 Sean Turner [Ballot Position Update] New position, Recuse, has been recorded by Sean Turner
2010-03-31
13 Russ Housley
[Ballot discuss]
The ASN.1 is not fully aligned with X9.44 (also ISO 18033-2).  X9.44
would use the id-ac-generic-hybrid OID (instead of id-rsa-kem), and
then a …
[Ballot discuss]
The ASN.1 is not fully aligned with X9.44 (also ISO 18033-2).  X9.44
would use the id-ac-generic-hybrid OID (instead of id-rsa-kem), and
then a parameter would indicate that only KEM should be used with
the certified public key.  The approach in this document does not
require parameter parsing, which seems like a good idea to me.

The Chair of X9F1 has been asked if this will be added to a future
update to X9.44, but he has not responded yet.  It would be very good
for X9.44 and an RFC to suggest the same solution going forward.

Section 2.1, "KDF3 (see [IEEE-P1363a])": IEEE 1363a-2004 does not
have KDF3; it does, however, define KDF2. Should this be KDF2, or
should the reference point to X9.44?

It looks like ANS X9.44 needs to be a normative, unless the KDF can be
found some other place.
2010-03-31
13 Russ Housley
[Ballot discuss]
I have reviewed draft-ietf-smime-cms-rsa-kem-12, and have couple of
small concern that I'd like to discuss before recommending approval of
the document:

- …
[Ballot discuss]
I have reviewed draft-ietf-smime-cms-rsa-kem-12, and have couple of
small concern that I'd like to discuss before recommending approval of
the document:

- It looks like the ASN.1 is not fully aligned with 18033-2 and X9.44.
I might be misinterpreting this, but to me it looks like 18033-2 and
X9.44 would use OID "id-ac-generic-hybrid" (instead of id-rsa-kem) as
the "top-level OID", and id-kem-rsa would be found in
GenericHybridParameters.kem structure.

The OID id-rsa-kem is not used in X9.44.  The Chair of X9F1 has been
asked if this will be added to a future update to X9.44, but he has
not responded yet.  It would be bad for X9.44 and an RFC to suggest
different aand incompatible solutions.

Section 2.1, "KDF3 (see [IEEE-P1363a])": IEEE 1363a-2004 does not
have KDF3; it does, however, define KDF2. Should this be KDF2, or
should the reference point to X9.44?

It looks like ANS X9.44 needs to be a normative, unless the KDF can be
found some other place.
2010-03-12
13 (System) Removed from agenda for telechat - 2010-03-11
2010-03-11
13 Cindy Morgan State Changes to IESG Evaluation::Revised ID Needed from IESG Evaluation by Cindy Morgan
2010-03-11
13 Lisa Dusseault [Ballot Position Update] New position, No Objection, has been recorded by Lisa Dusseault
2010-03-11
13 Dan Romascanu [Ballot Position Update] New position, No Objection, has been recorded by Dan Romascanu
2010-03-11
13 Amy Vezza State Changes to IESG Evaluation from Waiting for AD Go-Ahead by Amy Vezza
2010-03-11
13 Adrian Farrel [Ballot Position Update] New position, No Objection, has been recorded by Adrian Farrel
2010-03-11
13 Magnus Westerlund [Ballot Position Update] New position, No Objection, has been recorded by Magnus Westerlund
2010-03-11
13 Ralph Droms [Ballot Position Update] New position, No Objection, has been recorded by Ralph Droms
2010-03-11
13 (System) State has been changed to Waiting for AD Go-Ahead from In Last Call by system
2010-03-10
13 Ross Callon [Ballot Position Update] New position, No Objection, has been recorded by Ross Callon
2010-03-10
13 Robert Sparks [Ballot Position Update] New position, No Objection, has been recorded by Robert Sparks
2010-03-10
13 Cullen Jennings [Ballot comment]
Thanks for the examples in the back. I know they helped at least one implementor.
2010-03-10
13 Cullen Jennings [Ballot Position Update] New position, Yes, has been recorded by Cullen Jennings
2010-03-10
13 Pasi Eronen [Ballot comment]
Typo: A.2, "public key n,e)" -> "public key (n,e)"
2010-03-10
13 Pasi Eronen
[Ballot discuss]
I have reviewed draft-ietf-smime-cms-rsa-kem-12, and have couple of
small concern that I'd like to discuss before recommending approval of
the document:

- …
[Ballot discuss]
I have reviewed draft-ietf-smime-cms-rsa-kem-12, and have couple of
small concern that I'd like to discuss before recommending approval of
the document:

- It looks like the ASN.1 is not fully aligned with 18033-2 and X9.44.
I might be misinterpreting this, but to me it looks like 18033-2 and
X9.44 would use OID "id-ac-generic-hybrid" (instead of id-rsa-kem) as
the "top-level OID", and id-kem-rsa would be found in
GenericHybridParameters.kem structure.

(The OID id-rsa-kem doesn't seem to occur in 18033-2/X9.44 at all?
And BTW, it's *very* confusing to have two different OIDs named
id-rsa-kem and id-kem-rsa.)

- Section 2.1, "KDF3 (see [IEEE-P1363a])": IEEE 1363a-2004 doesn't
have KDF3; it does, however, define KDF2. Should this be KDF2, or
should the reference point to X9.44?

- It looks like ANS-9.44 needs to be normative references, since you
need the KDF to implement this.
2010-03-10
13 Pasi Eronen [Ballot Position Update] New position, Discuss, has been recorded by Pasi Eronen
2010-03-10
13 Ron Bonica [Ballot Position Update] New position, No Objection, has been recorded by Ron Bonica
2010-03-09
13 Russ Housley [Ballot comment]
2010-03-09
13 Russ Housley
[Ballot discuss]
The second Last Call expires 2010-03-11. The IESG should not declare
  that the downrefs called out in that Last Call are acceptiable …
[Ballot discuss]
The second Last Call expires 2010-03-11. The IESG should not declare
  that the downrefs called out in that Last Call are acceptiable to the
  community until the Last Call is actually over.  I do not expect any
  objection, but let's not jump the gun.
2010-03-09
13 Russ Housley [Ballot Position Update] Position for Russ Housley has been changed to Discuss from Yes by Russ Housley
2010-03-09
13 Lars Eggert [Ballot Position Update] Position for Lars Eggert has been changed to No Objection from Discuss by Lars Eggert
2010-03-09
13 Russ Housley [Ballot Position Update] Position for Russ Housley has been changed to Yes from Discuss by Russ Housley
2010-03-09
13 Lars Eggert
[Ballot discuss]
Sorry for playing downref police.

Section 6.1., paragraph 1:
>    [3DES-WRAP]      Housley, R. Triple-DES and RC2 Key Wrapping. RFC
>  …
[Ballot discuss]
Sorry for playing downref police.

Section 6.1., paragraph 1:
>    [3DES-WRAP]      Housley, R. Triple-DES and RC2 Key Wrapping. RFC
>                      3217. December 2001.

  DISCUSS: Downref: Normative reference to an Informational RFC: RFC
  3217
(ref. '3DES-WRAP'). Last-call didn't mention.


Section 6.1., paragraph 2:
>    [AES-WRAP]        Schaad, J. and R. Housley. Advanced Encryption
>                      Standard (AES) Key Wrap Algorithm. RFC 3394.
>                      September 2002.

  DISCUSS:  Downref: Normative reference to an Informational RFC: RFC
  3394
(ref. 'AES-WRAP'). Last-call didn't mention.
2010-03-09
13 Lars Eggert [Ballot Position Update] New position, Discuss, has been recorded by Lars Eggert
2010-03-08
12 (System) New version available: draft-ietf-smime-cms-rsa-kem-12.txt
2010-03-08
13 Russ Housley
[Ballot comment]
Section 2 says:
  >
  > The RSA-KEM Key Transport Algorithm SHOULD be considered for new CMS-
  > based applications as …
[Ballot comment]
Section 2 says:
  >
  > The RSA-KEM Key Transport Algorithm SHOULD be considered for new CMS-
  > based applications as a replacement for the widely implemented RSA
  > encryption algorithm specified originally in PKCS #1 v1.5 (see
  > [PKCS1] and Section 4.2.1 of [CMSALGS]), which is vulnerable to
  > chosen-ciphertext attacks.
  >
  s/SHOULD/should/  (this is not a statement about the protocol)
  Also, I think the discussion of attacks and security proofs in this
  section are better located in the Security Considerations.  There is
  already some discussion there, and these statements would be a good
  introduction to them.
2010-03-08
13 Russ Housley
[Ballot discuss]
Section 2.1 says:
  >
  > The Camellia key wrap algorithm (see [CAMELLIA]) SHOULD be
  > supported, and, if 3DES is …
[Ballot discuss]
Section 2.1 says:
  >
  > The Camellia key wrap algorithm (see [CAMELLIA]) SHOULD be
  > supported, and, if 3DES is supported as a content-encryption cipher,
  > then the Triple-DES Key Wrap (see [3DES-WRAP]) SHOULD also be
  > supported.
  >
  This should be broken into two statements:
  (1) The Camellia key wrap algorithm (see [CAMELLIA]) SHOULD be
      supported if Camellia is supported as a content-encryption
      cipher.
  (2) The Triple-DES Key Wrap algorithm (see [3DES-WRAP]) SHOULD be
      supported if Triple-DES is supported as a content-encryption
      cipher.

  Section 2.3 says:
  >
  > If the recipient wishes only to employ the RSA-KEM Key Transport
  > Algorithm with a given public key, the recipient MUST identify the
  > public key in the certificate using the id-rsa-kem object identifier
  > (see Appendix B). When the id-kta-rsa-kem algorithm identifier
  > appears in the SubjectPublicKeyInfo algorithm field, the encoding
  > SHALL omit the parameters field from AlgorithmIdentifier. That is,
  > the AlgorithmIdentifier SHALL be a SEQUENCE of one component, the
  > object identifier id-rsa-kem.
  >
  s/id-kta-rsa-kem/id-rsa-kem/
2010-03-08
13 Russ Housley [Ballot Position Update] New position, Discuss, has been recorded by Russ Housley
2010-03-08
13 Alexey Melnikov [Ballot Position Update] New position, No Objection, has been recorded by Alexey Melnikov
2010-02-25
13 Cindy Morgan Last call sent
2010-02-25
13 Cindy Morgan State Changes to In Last Call from Last Call Requested by Cindy Morgan
2010-02-25
13 Tim Polk [Ballot Position Update] New position, Yes, has been recorded for Tim Polk
2010-02-25
13 Tim Polk Ballot has been issued by Tim Polk
2010-02-25
13 Tim Polk Created "Approve" ballot
2010-02-25
13 Tim Polk State Changes to Last Call Requested from Waiting for AD Go-Ahead by Tim Polk
2010-02-25
13 Tim Polk Last Call was requested by Tim Polk
2010-02-23
13 Tim Polk Placed on agenda for telechat - 2010-03-11 by Tim Polk
2010-02-19
11 (System) New version available: draft-ietf-smime-cms-rsa-kem-11.txt
2010-01-07
13 (System) State has been changed to Waiting for AD Go-Ahead from In Last Call by system
2009-12-18
13 Samuel Weiler Request for Last Call review by SECDIR Completed. Reviewer: Stephen Kent.
2009-12-18
13 Amanda Baber IANA comments:

As described in the IANA Considerations section, we understand this
document to have NO IANA Actions.
2009-12-11
13 Samuel Weiler Request for Last Call review by SECDIR is assigned to Stephen Kent
2009-12-11
13 Samuel Weiler Request for Last Call review by SECDIR is assigned to Stephen Kent
2009-12-10
13 Amy Vezza State Changes to In Last Call from Last Call Requested by Amy Vezza
2009-12-10
13 Tim Polk Last Call was requested by Tim Polk
2009-12-10
13 Tim Polk State Changes to Last Call Requested from Publication Requested by Tim Polk
2009-12-10
13 Cindy Morgan State Changes to Publication Requested from Waiting for AD Go-Ahead::AD Followup by Cindy Morgan
2009-12-10
13 Cindy Morgan
1.a - Blake Ramsdell is the Shepherd. He's personally reviewed the
document and knows it is ready for IESG publication.
1.b - The document has …
1.a - Blake Ramsdell is the Shepherd. He's personally reviewed the
document and knows it is ready for IESG publication.
1.b - The document has been reviewed by key WG members. There are no
concerns about depth or breadth of the reviews.
1.c - There is no need for wider review.
1.d - There are no specific concerns that the AD and/or IESG should be
aware of.
1.e - The WG consensus is solid.
1.f - There has been no threat of an appeal.
1.g - The Shepherd has personally verified that the document satisfies
all ID nits. There are two normative references to informational RFCs:
RFC 2317 and RFC 3394.
1.h - The document splits it references.
1.i - The document has an IANA consideration and it is consistent with
the main body (there are no IANA considerations).
1.j - The reviewer has personally verified the ASN.1.
1.h - Write-up is as follows:

Technical Summary

The RSA-KEM Key Transport Algorithm is a one-pass (store-and-forward)
mechanism for transporting keying data to a recipient using the
recipient's RSA public key. This document specifies the conventions for
using the RSA-KEM Key Transport Algorithm with the Cryptographic Message
Syntax (CMS).

Working Group Summary

The draft was development in ANSI and ISO/IEC. The CMS part describes
where you put the OIDs is non-controversial. Note that the algorithm in
Appendix A and ASN.1 in Appendix B is aligned with ANS X9.44 and ISO/IEC
18033-2.

This document was scheduled to be on an IESG telechat in 2008-12-11, but
it was sent back to the S/MIME WG after comments were received from
Steve Kent during his SECDIR review on the public key certificate
parameters. This version addresses, Steve's comments as well as other
comments raised by Jim Schaad on the S/MIME mailing list.

Note that there is one remaining OID that to be registered, and this
will occur immediately following IESG approval.

Document Quality

As noted in the draft: The RSA-KEM Key Transport Algorithm in various
forms is being adopted in several draft standards as well as in
ANS-X9.44 and ISO/IEC 18033-2. It has also been recommended by the
NESSIE project [NESSIE].

Personnel

Blake Ramsdell is the document Shepherd. Tim Polk is the responsible
Security Area AD.
2009-12-08
10 (System) New version available: draft-ietf-smime-cms-rsa-kem-10.txt
2009-12-08
09 (System) New version available: draft-ietf-smime-cms-rsa-kem-09.txt
2009-12-07
13 (System) Sub state has been changed to AD Follow up from New Id Needed
2009-12-07
08 (System) New version available: draft-ietf-smime-cms-rsa-kem-08.txt
2009-07-29
13 Tim Polk State Changes to Waiting for AD Go-Ahead::Revised ID Needed from Waiting for AD Go-Ahead::AD Followup by Tim Polk
2009-07-07
13 (System) Sub state has been changed to AD Follow up from New Id Needed
2009-07-07
07 (System) New version available: draft-ietf-smime-cms-rsa-kem-07.txt
2009-07-06
13 Tim Polk Changed proto shepherd, as previous shepherd (Sean Turner) is now co-authoring.
2009-07-06
13 Tim Polk [Note]: 'proto shepherd is Blake Ramsdell <blaker@gmail.com>' added by Tim Polk
2009-07-06
13 Tim Polk
Answering questions 1.a-1.h in RFC 4858:

1.a - Sean Turner is the Shepherd.  He's personally reviewed the document
and knows it is ready for …
Answering questions 1.a-1.h in RFC 4858:

1.a - Sean Turner is the Shepherd.  He's personally reviewed the document
and knows it is ready for IESG publication.
1.b - The document has been reviewed by key WG members.  There are no
concerns about depth or breadth of the reviews.
1.c - There is no need for wider review.
1.d - There are no specific concerns that the AD and/or IESG should be aware
of, but note that the the Shepherd is not a cryptographer.  The Shepherd has
relied on members of the WG, ANSI, and ISO who are cryptographers for
algorithm "correctness."
1.e - The WG consensus is solid as a rock.
1.f - There has been no threat of an appeal.
1.g - The Shepherd has personally verified that the document satisfies all
ID nits.
1.h - The document splits it references.
1.i - The document has an IANA consideration and it is consistent with the
main body (there are no IANA considerations).
1.j - The reviewer has NOT personally verified the ASN.1, but knows Jim S.
has.
1.h - Write-up is as follows:

Technical Summary

The RSA-KEM Key Transport Algorithm is a one-pass (store-and-forward)
mechanism for transporting keying data to a recipient using the recipient's
RSA public key. This document specifies the conventions for using the
RSA-KEM Key Transport Algorithm with the Cryptographic Message Syntax (CMS).

Working Group Summary

The draft was development in ANSI and ISO/IEC.  The CMS part describes where
you put the OIDs is non-controversial.  Note that the algorithm in Appendix
A and ASN.1 in Appendix B is aligned with ANS X9.44 and ISO/IEC 18033-2.

Document Quality

As noted in the draft: The RSA-KEM Key Transport Algorithm in various forms
is being adopted in several draft standards as well as in ANS-X9.44 and
ISO/IEC 18033-2. It has also been recommended by the NESSIE project
[NESSIE].

Personnel

Sean Turner is the document Shepherd.  Tim Polk is the responsible Security
Area AD.
2009-07-06
13 Tim Polk [Note]: 'proto shepherd is Sean Turner <turners@ieca.com>' added by Tim Polk
2009-04-15
13 Tim Polk State Changes to Waiting for AD Go-Ahead::Revised ID Needed from Waiting for AD Go-Ahead by Tim Polk
2009-04-15
13 Tim Polk need a revision to address issues raised by Steve Kent
2008-11-19
13 Tim Polk Removed from agenda for telechat - 2008-12-11 by Tim Polk
2008-11-18
13 Tim Polk Placed on agenda for telechat - 2008-12-11 by Tim Polk
2008-11-10
06 (System) New version available: draft-ietf-smime-cms-rsa-kem-06.txt
2008-07-09
13 Samuel Weiler Request for Last Call review by SECDIR Completed. Reviewer: Stephen Kent.
2008-07-04
13 (System) State has been changed to Waiting for AD Go-Ahead from In Last Call by system
2008-06-30
13 Amanda Baber
IANA Last Call comments:

QUESTION: You reference an ASN.1 module identifier and point to
section B.3, but we cannot find one that should be or …
IANA Last Call comments:

QUESTION: You reference an ASN.1 module identifier and point to
section B.3, but we cannot find one that should be or has been
registered by IANA.

We understand that all IANA Actions have already been processed
and that this document has NO NEW IANA Actions.
2008-06-25
13 Samuel Weiler Request for Last Call review by SECDIR is assigned to Stephen Kent
2008-06-25
13 Samuel Weiler Request for Last Call review by SECDIR is assigned to Stephen Kent
2008-06-20
13 Amy Vezza State Changes to In Last Call from Last Call Requested by Amy Vezza
2008-06-20
13 Tim Polk State Changes to Last Call Requested from Publication Requested::External Party by Tim Polk
2008-06-20
13 Tim Polk Last Call was requested by Tim Polk
2008-06-20
13 (System) Ballot writeup text was added
2008-06-20
13 (System) Last call text was added
2008-06-20
13 (System) Ballot approval text was added
2007-11-06
(System) Posted related IPR disclosure: Sean Turner's Statement about IPR related to draft-ietf-smime-cms-rsa-kem-05 belonging to Various
2007-10-22
13 Tim Polk Needa an IPR disclosure statement.
2007-10-22
13 Tim Polk State Changes to Publication Requested::External Party from Publication Requested by Tim Polk
2007-10-19
13 Tim Polk Draft Added by Tim Polk in state Publication Requested
2007-10-19
05 (System) New version available: draft-ietf-smime-cms-rsa-kem-05.txt
2007-07-25
04 (System) New version available: draft-ietf-smime-cms-rsa-kem-04.txt
2007-05-31
03 (System) New version available: draft-ietf-smime-cms-rsa-kem-03.txt
2006-03-23
02 (System) New version available: draft-ietf-smime-cms-rsa-kem-02.txt
2003-10-24
01 (System) New version available: draft-ietf-smime-cms-rsa-kem-01.txt
2003-05-19
00 (System) New version available: draft-ietf-smime-cms-rsa-kem-00.txt