How to capture user identityId from original IdP using OpenID Connect (preview)

Question

I'm using an App Service with EasyAuth, integrated with B2C. Within B2C I've configured the OpenID Connect provider to point back to our corporate AAD tenant. The user journey and authentication are working as desired, however the user's sub and oid that are returned to EasyAuth contain the id of the user's B2C object, not from originating AAD tenant as I'd hoped. Anyway around this? Are custom policies needed?

Also referenced here on the B2C docs site: https://github.com/MicrosoftDocs/azure-docs/issues/14209#issuecomment-459063758

Thanks

Answer 1

Yes, you will need to use a custom policy to pass the oid of the AAD user (from the AAD token) as an additional claim in the B2C token.