On Tue, Dec 02, 2025 at 01:45:46PM -0600, Orie wrote:
> Hi,
> 
> I'm supportive of not giving JOSE / COSE implementers 2 PQ
> migration strategies to consider.
> 
> The design goals I had in mind were (still are):
> 
> - Crypto libraries that power JOSE, should be able to power COSE.
> - Algorithms and Key Formats should be aligned between JOSE and COSE for
> PQC.

Note that in COSE, any Integrated Encryption can be used as Key
Encryption (RFC 9052 Section 5.3). Thus, there is only one algorithm
per HPKE cipher suite, not two.


> - The same PQ and PQ/T options should be available for both.
> - Minimal changes to both JOSE and COSE to support KEMs, where changes are
> required, have them be consistent.

While JOSE needed changes for Integrated Encryption, COSE needs no
changes.


> In short, I hope we could modernize both JOSE and COSE while deferring
> significant cryptographic responsibility to HPKE.
> 
> I'm supportive of doing that, and I would prefer if there was not a similar
> but slightly different way of doing PQ, that would require different
> security analysis, and lead to different classes of attack.

ECDH-ES in COSE and JOSE is rather hair-raising cryptographically
(fortunately without any major attacks). KEMs would already avoid the
most major issues.




-Ilari

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

Reply via email to