Re: [openpgp] v5 in the crypto-refresh draft

[Paul Wouters <[e-mail]>]

On Mon, 7 Jun 2021, Peter Gutmann wrote:

>> We are happy to accept such proposed text, please send it to the list :)
>
> Well, if I write it people may be less happy with the text :-).  OK, how
> about, after the paragraph "Note that it is possible for there to be
> collisions of Key IDs", add:

Thanks :)

> -- Snip --
>
> There are no cryptographic issues introduced by this since the fingerprint is
> merely a fixed-length opaque value used to identify the variable-length
> structured data that makes up a public key.  In particular the move to SHA-256
> for V5 fingerprints was made not to address any cryptographic vulnerability
> but to avoid the perception that something insecure might be happening due to
> the use of SHA-1.
>
> -- Snip --

With no hats on, I would probably change the latter bit to:

   In particular the move to SHA-256 for V5 fingerprints was not made to address
   any cryptographic vulnerability, but was made to follow the generic
   guidelines of the cryptograhic community to sunset the use of SHA-1.

This would then also capture other reasons than the one you mention,
such as possible unavailability in crypto libaries or runtime modes
(FIPS) etc etc.

Paul