Re: [Cfrg] Deterministic signatures, revisit?

Tony Arcieri <> Mon, 09 October 2017 17:30 UTC

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From: Tony Arcieri <>
Date: Mon, 09 Oct 2017 10:30:19 -0700
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To: Dan Brown <>
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Subject: Re: [Cfrg] Deterministic signatures, revisit?
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This certainly keeps coming up. Beyond those papers see the previous "Side
channel attack and Edwards curves" thread on this list:

I think it's definitely a problem that needs to be addressed. I've seen
various proposals to do so as well, i.e. synthesizing "r" as a combination
of a random nonce and the message, so that fault attacks would, at the very
least, require an RNG failure as opposed to always being possible, due to
repeated "r" values for the same message. This should retain the extant
defense against RNG failures in general as we saw with ECDSA "k" values,
since it would still include hashing the message as part of the calculation.

Tony Arcieri