Re: [openpgp] Ed25519 and digest choices (issue 31)

Wiktor Kwapisiewicz <> Tue, 25 May 2021 07:37 UTC

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From: Wiktor Kwapisiewicz <>
To: Daniel Kahn Gillmor <>
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Date: Tue, 25 May 2021 09:37:22 +0200
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Subject: Re: [openpgp] Ed25519 and digest choices (issue 31)
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Hi Daniel,
> Either way, it seems that we need to clarify the standard.

I agree. I've been working on a specific use case (decryption and
validation of messages when public parts of the key are unavailable) and
the amount of cryptographic agility here is, in my opinion, unwarranted.

>From what I can see SHA-256 is the most prevalent hash for ed25519
signed messages now but I see no problem in SHOULD'ing SHA-512 to align
with existing standards.

Kind regards,