Re: [openpgp] Disadvantages of Salted Signatures

Vincent Breitmoser <look@my.amazin.horse> Sat, 09 December 2023 15:50 UTC

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From: Vincent Breitmoser <look@my.amazin.horse>
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Subject: Re: [openpgp] Disadvantages of Salted Signatures
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Hey Stephan,

On 09.12.23 16:30, Stephan Verbücheln wrote:
> Then I copy the file and create a new signature with a matching
> timestamp, using the trusted PGP implementation.

This seems like a case where the salt would be handed in explicitly then 
as a fixture to reproduce an identical signature, same as the timestamp.

Relatedly, it is not unlikely that subpackets will vary slightly between 
implementations and versions for various reasons, and more differences 
will likely have to be controlled for the use case you describe. For 
instance, some implementations started including an issuer fingerprint 
subpacket in recent years.

I don't have an opinion on salted vs unsalted. Point is, the use case 
you describe is neither trivial without salted signatures, nor 
impossible with them.

Cheers

  - V