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

Russ Housley <housley@vigilsec.com> Wed, 20 April 2016 18:07 UTC

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From: Russ Housley <housley@vigilsec.com>
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Date: Wed, 20 Apr 2016 14:07:32 -0400
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To: "Salz, Rich" <rsalz@akamai.com>, Daniel Kahn Gillmor <dkg@fifthhorseman.net>
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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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On Apr 20, 2016, at 7:27 AM, Salz, Rich <rsalz@akamai.com> wrote:

> This is okay with me, except for one pedantic clarification.  "Empty string" has a specific meaning in C, it's a single NUL byte.  Since our other uses of context including the NUL terminator, to avoid prefix attacks, then I think the wording needs some editing.

+1

It would be better to say that an “empty context” consists of zero bytes (or octets if you prefer).

Russ