Re: [openpgp] Disadvantages of Salted Signatures

Andrew Gallagher <andrewg@andrewg.com> Sat, 09 December 2023 10:48 UTC

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From: Andrew Gallagher <andrewg@andrewg.com>
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Date: Sat, 09 Dec 2023 10:47:44 +0000
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To: Stephan Verbücheln <verbuecheln@posteo.de>, openpgp@ietf.org
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Subject: Re: [openpgp] Disadvantages of Salted Signatures
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I’m not going to contest the central argument here as I don’t have the background knowledge, but on one minor point, I have a niggle:

On 9 Dec 2023, at 09:05, Stephan Verbücheln <verbuecheln@posteo.de> wrote:
> 
> It further requires the victim to sign the same data over and over
> again, which is not realistic in a practical scenario on the PGP layer
> because the timestamp will be different for each signature. There is no
> point in signing the same data with the same timestamp over and over
> again because it will always have the same result.

Strictly speaking, an action being pointless does not mean that it will not happen. One could imagine an automated system, say a notary service, being coerced into making a large number of identical signatures, even down to the timestamp.

A