phasing out SHA1 for digest creation

[Heiko Schäfer]

On 12/7/24 2:42 AM, Jacob Bachmeyer via Gnupg-devel wrote:
> Alternately, for the next PGP protocol version, including a nonce N in 
> the calculation of the digest H and also signing {N,H} instead of just 
> H should allow longer nonces without risking the signature integrity.  
> (I wonder if the SSH developers were thinking along those lines...) 

FWIW, OpenPGP version 6 signatures, specified in RFC 9580, do contain a 
salt (https://www.rfc-editor.org/rfc/rfc9580.html#section-5.2.3-2.10.1).

The signature hashing process starts with that salt 
(https://www.rfc-editor.org/rfc/rfc9580.html#section-5.2.4-2).