Re: [Cfrg] draft-irtf-cfrg-eddsa -- one final proposal for domain separation (context labels) for ed25519

"D. J. Bernstein" <djb@cr.yp.to> Wed, 20 April 2016 20:51 UTC

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From: "D. J. Bernstein" <djb@cr.yp.to>
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Subject: Re: [Cfrg] draft-irtf-cfrg-eddsa -- one final proposal for domain separation (context labels) for ed25519
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Paterson, Kenny writes:
> We are quite keen to get draft-irtf-cfrg-eddsa "shipped", as it's needed
> elsewhere in IETF and dependencies are building up.

Do any of those dependencies rely on having the signed object be
something other than a message?

I sent CFRG a message "Side inputs to signature systems" back in
September that raises several different objections to the "context"
concept. I believe that all of the objections remain valid. I didn't
notice until now that the concept was still under consideration; sorry!

---Dan