Subject: Note on AuthEnvelopedData

From: [email-masked] (Peter Gutmann)
Date: Fri, 15 Jun 2007 23:58:02 +1200

Late last year, in my "Strawman for adding a MDC to encrypted data", I
proposed, well, pretty much what the subject line said.  When Russ published
his AuthEnvelopedData draft, we had an off-list discussion about making it
part of the draft (or at least doing it in a manner that's compatible with the
draft) to make things a bit more uniform.  The idea is to use the standard
encrypt+HMAC mechanism already available in IPsec, SSL/TLS, SSH, and others,
and apply it to CMS as well.  Since this mechanism has been heavily analysed
and is already supported in many crypto libraries, as well as being a standard
mechanism for PKCS #11 (so it's supported in crypto hardware as well), this
seemed an obvious capability to include alongside CCM and GCM (it's also a
demontration that AuthEnvelopedData is flexible enough to handle different
auth+encrypt mechanisms :-).  Anyway, I was asked to mention this on the list
prior to AuthEnvelopedData going to last call, in case anyone was interested.

Peter.

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From: [email-masked] (Peter Gutmann)
Date: Sun, 17 Jun 2007 23:54:50 +1200

And a further comment, just to clarify the previous one: I'm happy with
AuthEnvelopedData going to last call in its current form.

Peter.