Transaction data authorization support with Verifiable Presentation

[frederikn-onespan]

I would like to integrate the support for transaction data authorization as defined in the OpenID for Verifiable Presentation v1 (definition in https://openid.net/specs/openid-4-verifiable-presentations-1_0.html#name-new-parameters). I had a look at the Verifier API swagger pages but could not find an example with transaction data in POST /openid4vc/verify. I had a look into the code base and found transaction data definitions in https://github.com/walt-id/waltid-identity/blob/main/waltid-libraries/protocols/waltid-openid4vp/src/commonMain/kotlin/id/walt/verifier/openid/models/authorization/AuthorizationRequest.kt but not further linked through in the protocol implementation. Did I miss something in my analysis? Is this still to be supported and if so is this planned? Thanks!

[linear]

WAL-741

[JakeFernandes98]

Thanks for raising this issue! We have started tracking this on our internal task board and an engineer will pick this up soon. We have taken this on lower priority, but if you have a project that relies on this please reach out to discuss options for support contracts for dedicated support via https://walt.id/contact

[waltkb]

Feature will be implemented in two halves:

1. Display transaction data to the wallet (implemented in Annex C Extensions #1597)
2. Verify transaction data hashes the wallet responds with: Will require saving the data, looking it up again at presentation, implement a VerificationPolicy to match the hashes against what hash we create on the backend for the inputted data (which is specific to the presentation format, e.g. for mdocs the transaction data is embedded in the device signed namespace of the document response)

[JakeFernandes98]

@frederikn-onespan Due to priorities, we will likely complete the second half at a later time. Please let us know if the fix so far is sufficient for your use case. We will merge this in soon but feel free to use the branch in the meantime. This is expected to be released as part of our 0.19.0 release in early April. Please let us know if you have any feedback based on trying it out for your use case!