Brian:

S/MIME does not use the signing time attribute as an input to certificate path 
validation.  It is not expected to come from a trusted time source.

Russ

> On Mar 27, 2024, at 5:16 PM, Sipos, Brian J. <[email protected]> wrote:
> 
> All,
> I’m working an application of COSE [1] with the expectation of using X509 
> certificates for data signing, so using the “x5…” header parameters [2] for 
> cert identification. This application is for store-and-forward data that may 
> have a lifetime of days, weeks, or longer so similar to S/MIME in some 
> aspects.
>  
> The issue I’m running into is how to handle the validity time period of a 
> certificate chain. Although S/MIME includes a “signing time” attribute [3] 
> there is no guidance in that spec about if, or how, it would be used as part 
> of PKIX validation or how to interpret or process certificate validity time 
> intervals differently than in RFC 5280 [4], which mandates validation based 
> on the current time. Using the current time doesn’t seem appropriate for 
> S/MIME either, but I don’t see any alternative documented.
>  
> Does anyone on the COSE mailing list have any thoughts or references to help 
> me out?
> Or maybe this is a better question for LAMPS WG directly?
> Since COSE is intended for the store-and-forward use case, it might be a good 
> errata to include a statement in the security considerations section..?
>  
> Thanks,
> Brian S.
>  
> [1] https://www.ietf.org/archive/id/draft-ietf-dtn-bpsec-cose-03.html
> [2] https://www.rfc-editor.org/rfc/rfc9360.html
> [3] https://datatracker.ietf.org/doc/html/rfc8551#section-2.5.1
> [4] https://www.rfc-editor.org/rfc/rfc5280#section-6.1.3
>  
> _______________________________________________
> COSE mailing list
> [email protected] <mailto:[email protected]>
> https://www.ietf.org/mailman/listinfo/cose

_______________________________________________
COSE mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/cose

Reply via email to