Re: [TLS] TLS 1.2 Long-term Support Profile draft posted

Peter Gutmann <> Sun, 20 March 2016 06:36 UTC

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From: Peter Gutmann <>
To: Dave Garrett <>, "" <>
Thread-Topic: [TLS] TLS 1.2 Long-term Support Profile draft posted
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Date: Sun, 20 Mar 2016 06:36:09 +0000
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Subject: Re: [TLS] TLS 1.2 Long-term Support Profile draft posted
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Dave Garrett <> writes:

>It would be a lot simpler, safer, and interoperable to just mandate use of
>the Extended Master Secret Extension [RFC 7627].

Yeah, in hindsight it makes more sense, I'll update the draft, although the
update may not get in before the IETF freeze.  I was trying to avoid having to
run two parallel hashing operations throughout the handshake (the other one
being for the Finished message), but EMS is just a much more comprehensive
solution (like EtM, it's one of those things where you think "why wasn't this
added to TLS years ago") even if it means running two lots of hashing.

The other update is to clean up the wording around which extensions TLS-LTS
implies, replacing the current wording scattered all over the draft.