Creation of a Registry for smime-type Parameter Values

Abstract

Secure/Multipurpose Internet Mail Extensions (S/MIME) defined the Content-Type parameter "smime-type". As the list of defined values for that parameter has increased, it has become clear that a registry is needed to document these values. This document creates the registry, registers the current values, and specifies the policies for registration of new values.

Status of This Memo

This is an Internet Standards Track document.

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). Further information on Internet Standards is available in 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/rfc7114.

Copyright Notice

Copyright © 2014 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 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.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   3
   3.  Security Considerations . . . . . . . . . . . . . . . . . . .   3
   4.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   4
     4.1.  Normative References  . . . . . . . . . . . . . . . . . .   4
     4.2.  Informative References  . . . . . . . . . . . . . . . . .   4

1. Introduction

Secure/Multipurpose Internet Mail Extensions (S/MIME) defined the Content-Type "application/pkcs7-mime" and the parameter "smime-type", along with four valid values for the parameter [RFC3851]. Certificate Management over CMS (CMC) added two new parameter values [RFC5273]. [RFC5751] replaced RFC 3851 and registered the application/pkcs7-mime media type, but did not create a registry for the smime-type values.

Enhanced Security Services for S/MIME [RFC2634] and Securing X.400 Content with S/MIME [RFC3854] also add smime-type values.

When Enrollment over Secure Transport [RFC7030] added another parameter value, it became clear that a registry for smime-type parameter values is necessary. Section 2 creates this registry, registers the current values that are defined in previously published documents, and specifies the policies for registration of new values.

2. IANA Considerations

IANA has changed the reference field for the media type application/ pkcs7-mime to refer to [RFC5751] and this document. This document replaces the references to RFC 5273 and RFC 7030, which are no longer needed.

IANA has created a new sub-registry under the "MIME Media Type Sub- Parameter Registries" top-level registry. The new registry is "Parameter Values for the smime-type Parameter", and it references this document and [RFC5751]. The initial values for the registry are as follows:

      +----------------------+-----------------------------------+
      |  smime-type value    |  Reference                        |
      +----------------------+-----------------------------------+
      | certs-only           | [RFC5751], Section 3.2.2          |
      | CMC-Request          | [RFC5273], Section 3              |
      | CMC-Response         | [RFC5273], Section 3              |
      | compressed-data      | [RFC5751], Section 3.2.2          |
      | enveloped-data       | [RFC5751], Section 3.2.2          |
      | enveloped-x400       | [RFC3854], Section 3.3.1          |
      | server-generated-key | [RFC7030], Section 4.4.2          |
      | signed-data          | [RFC5751], Section 3.2.2          |
      | signed-receipt       | [RFC2634], Section 2.4, bullet 10 |
      | signed-x400          | [RFC3854], Section 3.2.1          |
      +----------------------+-----------------------------------+

New values can be registered using the Specification Required policy, as defined in [RFC5226]. The S/MIME Message Specification [RFC5751], Section 3.2.2, specifies guidelines for assigning new smime-type parameter values, and those guidelines apply to the assignment of values in this registry.

3. Security Considerations

This document is purely administrative and presents no security issues.

4. References

4.1. Normative References

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.
   
   [RFC5751]  Ramsdell, B. and S. Turner, "Secure/Multipurpose Internet
              Mail Extensions (S/MIME) Version 3.2 Message
              Specification", RFC 5751, January 2010.

4.2. Informative References

   [RFC2634]  Hoffman, P., "Enhanced Security Services for S/MIME", RFC
              2634, June 1999.
   
   [RFC3851]  Ramsdell, B., "Secure/Multipurpose Internet Mail
              Extensions (S/MIME) Version 3.1 Message Specification",
              RFC 3851, July 2004.
   
   [RFC3854]  Hoffman, P., Bonatti, C., and A. Eggen, "Securing X.400
              Content with Secure/Multipurpose Internet Mail Extensions
              (S/MIME)", RFC 3854, July 2004.
   
   [RFC5273]  Schaad, J. and M. Myers, "Certificate Management over CMS
              (CMC): Transport Protocols", RFC 5273, June 2008.
   
   [RFC7030]  Pritikin, M., Yee, P., and D. Harkins, "Enrollment over
              Secure Transport", RFC 7030, October 2013.

Author's Address

Barry Leiba
Huawei Technologies

   Phone: +1 646 827 0648
   EMail: barryleiba@computer.org
   URI:   http://internetmessagingtechnology.org/