Disclosure with OpenID4VP

Generic disclosure

This diagram shows how OpenID4VP is implemented within the NL Wallet Solution.

OpenID for Verifiable Presentations - draft 20 is used as basis for the implementation.

Client authentication is done using the x509_san_dns Client Identifier Scheme. Other Client Identifier Schemes are currently not supported.

The reponse mode is direct_post.jwt. Other response modes are currently not supported.

In more detail, the protocol works as follows:

        sequenceDiagram
    autonumber

    actor User
    participant RP as Verifier
    participant WalletServer as Verifier Endpoint ('OV')
    participant Wallet
    User->>RP: Start action to disclose attributes
    RP->>WalletServer: initiate transaction
    WalletServer ->>RP: return session_token    
    RP ->>+ Wallet: authorization request (request_uri) (open wallet through universal link or scan QR on another device)
    Wallet ->> WalletServer: request Request Object (using request_uri)
    note over WalletServer: Request Object (signed) also contains 'client_metadata',<Br/> including jwks with an ephemeral key for encrypting the authorization response
    WalletServer ->> Wallet: response with (signed) Request Object
    Wallet ->>+ User: request user consent for disclosure
    User ->> Wallet: provide consent for disclosure of attributes (using PIN)
    Wallet->> WalletServer: authorization response (VP Token) (JWE using ephemeral key)
    WalletServer ->>WalletServer: Validate VP Token
    WalletServer ->> Wallet: authorization response (redirect_uri with session_token)
    Wallet ->> RP: redirect to the redirect URI (session_token)
    RP ->> WalletServer: fetch response data (session_token)
    WalletServer ->> RP: response data (verified attributes)

From Verifier’s website or app, user decides to start an action that requires disclosed attributes
A request goes from Verifier App to OV to start a disclosure session
OV returns session_token created for this session
The OpenID4VP Authorization Request request_uri parameter is put in a UL or QR code, which is either opened or scanned by the Wallet.
Wallet requests the request object from the given request_uri. The request object contains the response_uri
Verifier returns request object (signed)
The requested attributes and the identity of the verifier are presented to the user for consent
User provides consent (using PIN)
Response is posted back to Verifier Endpoint (‘OV’) (endpoint address is supplied in response_uri within the Request Object)
‘OV’ verifies the received VP Token
Verifier endpoint returns a redirect_uri back into the verfier’s website or app
Redirect to verifier using redirect_uri.
Verifier’s website or app requests session results from ‘OV’ using session_token
‘OV’ returns session results