Subject: [Jmap] Robert Wilton's No Objection on draft-ietf-jmap-smime-09: (with COMMENT)

From: Robert Wilton via Datatracker <[email-masked]>
Date: Wed, 20 Oct 2021 02:36:07 -0700

Robert Wilton has entered the following ballot position for
draft-ietf-jmap-smime-09: No Objection

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COMMENT:
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Hi,

I have to confess that I don't know IMAP, and hence my question may have an
obvious answer, but it is unclear to me whether a server supporting the
smimeverify capability implies that it SHOULD also support checking the S/MIME
signature at delivery time?  If this is the case, should this be clarified,
perhaps in section 3?

I.e., section 3 states:
   Servers supporting
   _this_ specification MUST add a property called
   "urn:ietf:params:jmap:smimeverify" to the capabilities object.

E.g., section 4.1 states:

   signed:  S/MIME signed message, but the signature was not yet
      verified.  Some servers might not attempt to verify a signature
      until a particular message is requested by the client.  JMAP
      servers compliant with this document SHOULD return "signed/
      verified" or "signed/failed" instead of this signature status.

These two statements seem to imply that a server returning the smimeverify
capability SHOULD also support checking the S/MIME signature at delivery
because they SHOULD either return signed/verified or signed/failed for a
request for smimeStatusAtDelivery, which at least implies that they have
previously checked the signature when it was delivered.  Is that was is
intended?

Thanks,
Rob

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From: Alexey Melnikov <[email-masked]>
Date: Thu, 21 Oct 2021 15:13:59 +0100

Hi Robert,

The intent was to require support of all attributes specified in the draft.
> previously checked the signature when it was delivered.  Is that was is
I think you are saying that bare "signed" will never be returned if the 
server also supports smimeStatusAtDelivery.

Good question, let me think about it and I will come back to you.

Best Regards,

Alexey