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Re: [TLS] Why are the brainpool curves not allowed in TLS 1.3?

"Blumenthal, Uri - 0553 - MITLL" <uri@ll.mit.edu> Tue, 17 July 2018 17:28 UTC

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From: "Blumenthal, Uri - 0553 - MITLL" <uri@ll.mit.edu>
To: Eric Rescorla <ekr@rtfm.com>, Johannes Merkle <johannes.merkle@secunet.com>
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Thread-Topic: [TLS] Why are the brainpool curves not allowed in TLS 1.3?
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Date: Tue, 17 Jul 2018 17:28:44 +0000
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Subject: Re: [TLS] Why are the brainpool curves not allowed in TLS 1.3?
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> We've
> generally decided to limit the number of algorithms we recommend (the
> Recommended) column in the registry. I have trouble seeing any situation in
> which we would have these curves as Recommended. And so "at hand" really
> means (1) code points assigned and (2) some small number of people who
> don't follow our Recommended advice do them

But the draft states
   Values within "obsolete_RESERVED" ranges are used in previous
   versions of TLS and MUST NOT be offered or negotiated by TLS 1..3

So its not merely a recommendation.

 

Yes, what I am saying is that even if we were to remove that text it would not significantly change matters.

 

I think “MUST NOT” is way too strong in this context, and “must” be softened.

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