Add support for claims request parameter

[nanderstabel]

Description

The library should be able to add the request for claims in the SIOP Requests and the Provider should be able to handle those claims accordingly. As specified in the OICD-core standard, claims can be requested by the Relying Party using the claims request parameter.

There are two types of claims:

• 'self-attested' claims, as specified in the SIOPv2 standard
• cryptographically verifiable claims issued by trusted third-party sources as described in OpenID4VP

Both of them need to be implemented.

Motivation

In OpenID Connect, a claim is a piece of information about the user, such as their name or email address, that the Relying Party can request from the OpenID Provider. The claims request parameter is used by the Relying Party to specify which claims it wants to receive in the ID token or UserInfo response.

The claims parameter value is a JSON object that describes the set of requested claims, including the name of the claim and any additional parameters needed to process the claim. The OpenID Provider may or may not provide the requested claims based on the user's consent and the authorization policies of the Provider.

By adding support for the claims request parameter, our library will allow Relying Parties to request specific claims about the user and receive them in a standardized way, making it easier for them to integrate with our library and comply with OpenID Connect standards.

Resources

OICD-core claims specification
SIOP-v2
OpenID4VP

To-do List

• feat: add claims and scope support #18
• feat: add claims and scope support #18
• Support aggregated and distributed claims
• Add initial support for verifiable presentations #9