[Openid-specs-digital-credentials-protocols] Minutes from 16th May 2024 DCP WG call

[Brian Campbell]

On Fri, May 17, 2024 at 6:49 AM Orie Steele via
Openid-specs-digital-credentials-protocols <
openid-specs-digital-credentials-protocols at lists.openid.net> wrote:

> You can use sd-jwt to produce the W3C Verifiable Presentation object:
>
>
> https://www.w3.org/TR/vc-jose-cose/#securing-json-ld-verifiable-presentations-with-sd-jwt
>

What is/was the rationale for using sd-jwt to produce the W3C Verifiable
Presentation object? As I said over in this PR
<https://github.com/w3c/vc-jose-cose/pull/270#issuecomment-2108832855>
(which I'm now regretting having gotten involved in),maybe I'm not seeing
the grand vision or something but securing a VP with SD-JWT doesn't really
make sense to me.


However this requires you to present a presentation as if it were a
> credential.
>
> And it creates a situation where you can have key binding in the
> credentials and for the presentation layer.
>
> Our implementation supports this, but it's awkward.
>
> This stems from W3C defining a protocol message without having a concrete
> protocol that is also defined, as opposed to just a data format.
>
> As far as I know protocols decide if they want to support W3C
> presentations or just W3C credentials... And oidc has so far, never
> supported W3C presentations.
>

Again, maybe I'm not seeing the grand vision or something but that doesn't
sound right to me*. I would agree though that the protocol and message
layering in all this is sometimes confused and often confusing.

*  these seem like they are W3C Verifiable Presentations...
https://openid.net/specs/openid-4-verifiable-presentations-1_0-20.html#appendix-A.1.1.3-5
https://openid.net/specs/openid-4-verifiable-presentations-1_0-20.html#appendix-A.1.2.3-5





>
> On Fri, May 17, 2024, 2:20 AM Jan Vereecken via
> Openid-specs-digital-credentials-protocols <
> openid-specs-digital-credentials-protocols at lists.openid.net> wrote:
>
>> Hi Joseph and other members,
>>
>>
>>
>> Regarding
>>
>>
>>
>> > Two people asked about how to return multiple credentials fulfilling
>> the same single requirement; that hadn’t come up before and we probably
>> need a way to express if the verifier wants all the matches or just one -
>> new issue to be opened for that.
>>
>>
>>
>> I just want to qualify my question further.
>>
>>
>>
>> I was thinking more of the case where a single presentation is answering
>> multiple credentials requests.
>>
>>
>>
>> Specifically W3C VCDM enables presentation of multiple credentials, bound
>> to the same identifier, in a single presentation object. In contrast, to my
>> knowledge,  SD-JWT VC does not have this.
>>
>>
>>
>> For the example, let’s conceptually represent this as jwt_vp_json_a =
>> [jwt_vc_json_1, jwt_vc_json_2], where jwt_vc_json_1 answers my_cred_1 and
>> jwt_vc_json_2 answers my_cred_2.
>>
>>
>>
>> Does the solution envisaged then repeat the presentation object and
>> figure out in the submission how to reference the correct credential
>>
>>
>>
>> {
>>
>>   “my_cred_1”: “jwt_vp_json_a”,
>>
>>   “my_cred_2”: “jwt_vp_json_a”
>>
>> }
>>
>>
>>
>> Or, do we require multiple presentation object, each one replying to
>> exactly one of the request
>>
>>
>>
>> jwt_vp_json_b = [jwt_vc_json_1]
>>
>> jwt_vp_json_c = [jwt_vc_json_2]
>>
>>
>>
>> {
>>
>>   “my_cred_1”: “jwt_vp_json_b”,
>>
>>   “my_cred_2”: “jwt_vp_json_c”
>>
>> }
>>
>>
>>
>> Or, do we allow more flexibility, but increasing complexity in response
>> structure.
>>
>>
>>
>> [
>>
>>   {
>>
>>     “request”: [“my_cred_1”, “my_cred_1”],
>>
>>     “response”: “jwt_vp_json_a”
>>
>>   }
>>
>> ]
>>
>>
>>
>> Regards,
>>
>> Jan
>>
>>
>>
>> *From: *Openid-specs-digital-credentials-protocols <
>> openid-specs-digital-credentials-protocols-bounces at lists.openid.net> on
>> behalf of Joseph Heenan via Openid-specs-digital-credentials-protocols <
>> openid-specs-digital-credentials-protocols at lists.openid.net>
>> *Date: *Thursday, 16 May 2024 at 18:34
>> *To: *Digital Credentials Protocols List <
>> openid-specs-digital-credentials-protocols at lists.openid.net>
>> *Cc: *Joseph Heenan <joseph at authlete.com>
>> *Subject: *[Openid-specs-digital-credentials-protocols] Minutes from
>> 16th May 2024 DCP WG call
>>
>>
>>
>> Participants:
>>
>>
>>
>> Joseph Heenan
>>
>> Kristina Yasuda
>>
>> Daniel Fett
>>
>> Andreea Prian
>>
>> Arjen van Veen
>>
>> Bjorn Hjelm
>>
>> Brian Campbell
>>
>> gabe
>>
>> Jan Vereecken
>>
>> Jin Wen
>>
>> Juba Saadi
>>
>> Michael Jones
>>
>> Oliver Terbu
>>
>> Pedro Felix
>>
>> Rajvardhan Deshmukh
>>
>> Ryan Galluzzo
>>
>> Sebastian Birckerle
>>
>> Sebastian Bahloul
>>
>> Sudesh Shetty
>>
>> Lukasz Jaromin
>>
>>
>>
>>
>>
>> *Events:*
>>
>>
>>
>> There will be a hybrid meeting with in-person participation for those at
>> Identiverse; if you would like to attend in person please register on
>> eventbrite:
>>
>>
>>
>>
>> https://www.eventbrite.com/e/openid-foundation-dcp-wg-hybrid-meeting-at-identiverse-tickets-902324616217
>>
>>
>>
>> It was proposed to cancel the normal working group meetings during
>> Identiverse & EIC and no one objected.
>>
>>
>>
>>
>>
>>
>>
>> *VP Query Language Proposal:*
>>
>>
>>
>> Daniel shared the latest thoughts on the query language, presenting an
>> evolution of the proposal created during IIW that meets the various
>> requirements that were agreed by the working group, that includes some
>> feedback from implementers that looked at the previous proposal:
>> https://hackmd.io/1siVhjzOTWOE9ppdF_t57A?view
>>
>>
>>
>> There was some discussion over the how the logic of “and/or” requests is
>> expressed; Daniel said the current proposal is the simplest they could come
>> up with.
>>
>>
>>
>> Two people asked about how to return multiple credentials fulfilling the
>> same single requirement; that hadn’t come up before and we probably need a
>> way to express if the verifier wants all the matches or just one - new
>> issue to be opened for that.
>>
>>
>>
>> Jan asked where both ‘format’ and the name of the format specific
>> parameters object (e.g. “vc+sd-jwt”) are required. Daniel said that
>> ‘format' is necessary so there is a clear place for the verifier to figure
>> out if it supports the requested format, and then there’s also a desire to
>> collect the format specific keys into a sub-object.
>>
>>
>>
>> Jan asked about implementations. There aren’t any yet that we’re aware of.
>>
>>
>>
>> Kristina asked if we wanted to proceed with a new query language format
>> and if this proposal was a good way to proceed.
>>
>>
>>
>> Jan, Arjen, Brian, Michael J, Oliver, Gabe agreed it was a useful
>> starting point. No one raised objections to using it as a starting point.
>> Oliver wasn’t sure about the advances syntax features in example 7.
>>
>>
>>
>> Next step is to open an issue.
>>
>>
>>
>>
>>
>> *VP Transaction Data:*
>>
>>
>>
>> Kristina has opened 4 new issues for 4 specific points that need
>> discussion, all tagged with the ’transaction data’ label.
>>
>>
>>
>> Issue 173: The verifier needs an easy way to check the wallet is approve
>> what it’s requested; given the difficulties of comparing json objects
>> having the transaction request base64url encoded in the request & response
>> seems like the best solution right now.
>>
>>
>>
>>
>>
>> *VP PRs:*
>>
>>
>>
>> #175 Add text/diagram for siopv2 conditional cred req flow
>>
>> https://github.com/openid/OpenID4VP/pull/175 to solve
>> https://github.com/openid/OpenID4VP/issues/86
>>
>>
>>
>> Please read and give feedback.
>>
>>
>>
>>
>>
>> *VCI PRs/issues:*
>>
>>
>>
>> https://github.com/openid/OpenID4VCI/pull/314
>>
>>
>>
>> Removed authorization_pending as discussed in previous meetings and
>> notified to mailing list. No objections raised.
>>
>>
>>
>>
>>
>> https://github.com/openid/OpenID4VCI/pull/319
>>
>>
>>
>> As per previous working group discussions, clarify how encryption works
>> on batch endpoint - please review.
>>
>>
>>
>>
>>
>>
>>
>> https://github.com/openid/OpenID4VCI/pull/321 - adds a new error code to
>> credential endpoint for the issuer to indicate it’s denying the request -
>> please review.
>>
>>
>>
>>
>>
>>
>>
>> https://github.com/openid/OpenID4VP/issues/171 - “nonce” handling should
>> be more explicit.
>>
>>
>>
>> Kristina pointed out that SD-JWT & W3C LDP sections do contain wording;
>> Oliver will review it and raise a PR if it can be improved.
>>
>>
>>
>>
>>
>>
>>
>> https://github.com/openid/OpenID4VP/issues/124 - client_id_scheme
>> security considerations
>>
>>
>>
>> We need to come to a decision on this. The feeling when discussed at OSW
>> seemed to be folding the client_id_scheme into the client_id in some way so
>> the existing iss/aud fields in JWTs can be used etc. To be discussed on
>> next week’s WG calls.
>>
>>
>>
>>
>> --
>> Openid-specs-digital-credentials-protocols mailing list
>> Openid-specs-digital-credentials-protocols at lists.openid.net
>>
>> https://lists.openid.net/mailman/listinfo/openid-specs-digital-credentials-protocols
>>
> --
> Openid-specs-digital-credentials-protocols mailing list
> Openid-specs-digital-credentials-protocols at lists.openid.net
>
> https://lists.openid.net/mailman/listinfo/openid-specs-digital-credentials-protocols
>

-- 
_CONFIDENTIALITY NOTICE: This email may contain confidential and privileged 
material for the sole use of the intended recipient(s). Any review, use, 
distribution or disclosure by others is strictly prohibited.  If you have 
received this communication in error, please notify the sender immediately 
by e-mail and delete the message and any file attachments from your 
computer. Thank you._
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openid.net/pipermail/openid-specs-digital-credentials-protocols/attachments/20240517/0c6f6080/attachment-0001.html>