Subject: [smime] New ID of possible interest

From: "Herzog, Jonathan - 0668 - MITLL" <[email-masked]>
Date: Thu, 21 Apr 2011 10:09:21 -0400

I would like to inform the SMIME working group of a newly-submitted
Internet Draft that may be of interest:

 The With-MAC key-wrapping algorithm for Cryptographic Message Syntax

  draft-herzog-withmac-keywrap-00

Abstract:

   This document describes a new key-wrapping algorithm to be used in
   the EnvelopedData, AuthenticatedData and AuthEnvelopedData structures
   of the Cryptographic Message Syntax.  Because these structures do not
   provide data-origin authentication, a recipient cannot
   cryptographically verify that the plaintext received was the
   plaintext encapsulated by the message's original sender.  The With-
   MAC key-wrapping algorithm allows an EncryptedKey value to hold both
   a wrapped symmetric key and a MAC value on the data to be
   authenticated.  When used in EnvelopedData, AuthenticatedData and
   AuthEnvelopedData structures, therefore, these structures can achieve
   data-origin authentication (in some circumstances) using only
   symmetric-key algorithms.

https://datatracker.ietf.org/doc/draft-herzog-withmac-keywrap/

A side note: this draft should probably be read in combination with our previous draft on static-static ECDH (https://datatracker.ietf.org/doc/draft-herzog-static-ecdh/). That draft described how a sender might use a certified ECDH key to create an EnvelopedData structure (for example). It is unclear, however, how such a sender could also provide data-origin authentication without using digital signatures. However, that requires a certified signature-capable key, something they may not have. This draft provides an alternate approach-- the sender provides a MAC value for each recipient.

We welcome all comments and reviews.

Thank you.

-- 
Jonathan Herzog							voice:  (781) 981-2356
Technical Staff							fax:    (781) 981-7687
Cyber Systems and Technology Group		email:  [email-masked]
MIT Lincoln Laboratory               			www:    http://www.ll.mit.edu/CST/
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