[openpgp] Re: I-D Action: draft-ietf-openpgp-persistent-sy mmetric-keys-02.txt

On 05/11/2025 11:33, Daniel Huigens wrote:
> On Wednesday, November 5th, 2025 at 11:54, Andrew Gallagher <[email protected]> wrote:
> 
> If we ever come up with something that
> requires a completely different API, I think defining a new packet
> version could also be warranted (as we'd also need an SEIPDv3).
...
> Personally I think that in the public key algorithms registry,
> saying 0 = no public key algorithm, use symmetric crypto instead,
> makes sense. How we want to spell that in the registry is of course
> up for debate, but I think it also makes sense that symmetric crypto
> means AEAD.
...
> Having 0 point to a registry with a single entry ("AEAD") which in
> turn points to another registry (AEAD algorithms) seems like overkill
> that we'll never need, IMHO.
OK, I think we're closer to agreement than it may seem then. ;-) If we 
think AEAD is sufficiently flexible for the foreseeable future, and we 
will have to bump packet version numbers anyway if/when we deprecate it, 
then it might be reasonable to register "0 means PSK" without any 
further explanation in the asymmetric algorithms registry, and hardcode 
AEAD in the specification of "PSK version 6", without a new registry.

I think the only other major concern would be whether there is 
sufficient protection against cross-algorithm attacks in signatures, 
given that there is no field for the AEAD algorithm code point (unlike 
SEIPDv2). Would it be sufficient to encrypt an algorithm-dependent 
constant string instead of a null string?

A

_______________________________________________
openpgp mailing list -- [email protected]
To unsubscribe send an email to [email protected]