Releasing Claims - OpenID Connect Authentication

Defined scopes for a given service definition control and build attribute release policies internally. Such attribute release policies allow one to release standard claims, remap attributes to standard claims, or define custom claims and scopes altogether.

It is also possible to define and use free-form attribute release policies outside the confines of a scope to freely build and release claims/attributes.

:warning: ID Token Claims

Per OpenID Connect specification, individual claims requested by OpenID scopes, such as profile, email, etc. are only put into the OpenID Connect ID token when the response type is set to id_token. To assist with backward compatibility and non-complying application integrations, CAS provides options to force-include claims in the ID token, though please note that this should be a last workaround as doing so most likely is in violation of the OpenID Connect specification. Claims should be requested from the userinfo/profile endpoints in exchange for an access token as indicated by the appropriate response type.

  • The following service definition will decide on relevant attribute release policies based on the semantics of the scopes profile and email. There is no need to design or list individual claims as CAS will auto-configure the relevant attribute release policies:

    

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    {
  "@class" : "org.apereo.cas.services.OidcRegisteredService",
  "clientId": "client",
  "clientSecret": "secret",
  "serviceId" : "...",
  "name": "OIDC",
  "id": 1,
  "scopes" : [ "java.util.HashSet",
    [ "openid", "profile", "email" ]
  ]
}

  • A scope-free attribute release policy may just as equally apply, allowing one in the following example to release userX as a claim:

    

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    {
  "@class" : "org.apereo.cas.services.OidcRegisteredService",
  "clientId": "client",
  "clientSecret": "secret",
  "serviceId" : "...",
  "name": "OIDC",
  "id": 1,
  "attributeReleasePolicy" : {
    "@class" : "org.apereo.cas.services.ReturnMappedAttributeReleasePolicy",
    "allowedAttributes" : {
      "@class" : "java.util.TreeMap",
      "userX" : "groovy { return attributes['uid'].get(0) + '-X' }"
    }
  }
}

    A scope-free attribute release policy is activated when the service definition does not specify any scopes, or the only scope that the service definition contains is the openid scope. A scope-free attribute release policy has the ability to process release claims regardless of the requested scopes, which may prove useful in scenarios where a relying party needs to receive claims and yet does not correctly or sufficiently specify a scope in authorization requests.

    :information_source: Usage

    You should consider using a scope-free attribute release policy only in very advanced and challenging use cases, typically to make a rather difficult client application integration work.

  • It is also possible to mix free-form release policies with those that operate based on a scope by chaining such policies together. For example, the below policy allows the release of user-x as a claim, as well as all claims assigned and internally defined for the standard email scope.

    

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    {
  "@class": "org.apereo.cas.services.OidcRegisteredService",
  "clientId": "client",
  "clientSecret": "secret",
  "serviceId": "...",
  "name": "OIDC",
  "id": 10,
  "attributeReleasePolicy": {
    "@class": "org.apereo.cas.services.ChainingAttributeReleasePolicy",
    "policies": [
      "java.util.ArrayList",
      [
        {
          "@class" : "org.apereo.cas.services.ReturnAllowedAttributeReleasePolicy",
          "allowedAttributes" : [ "java.util.ArrayList", [ "cn", "uid", "givenName" ] ],
          "order": 0  
        },
        {
          "@class": "org.apereo.cas.services.ReturnMappedAttributeReleasePolicy",
          "allowedAttributes": {
            "@class": "java.util.TreeMap",
            "user-x": "groovy { return attributes['uid'].get(0) + '-X' }"
          },
          "order": 1
        },
        {
          "@class": "org.apereo.cas.oidc.claims.OidcEmailScopeAttributeReleasePolicy",
          "order": 2
        }
      ]
    ]
  }
}

    To prepare CAS to support and integrate with Apache Groovy, please review this guide.

    It is also possible to mix scopes and free-form policies together using the following short-hand:

    

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    {
  "@class": "org.apereo.cas.services.OidcRegisteredService",
  "clientId": "client",
  "clientSecret": "secret",
  "serviceId": "^https://.+",
  "name": "Sample",
  "id": 1,
  "scopes" : [ "java.util.HashSet", [ "email", "profile", "openid" ] ],
  "supportedGrantTypes": [ "java.util.HashSet", [ "authorization_code" ] ],
  "supportedResponseTypes": [ "java.util.HashSet", [ "code" ] ],
  "attributeReleasePolicy": {
    "@class": "org.apereo.cas.oidc.claims.OidcScopeFreeAttributeReleasePolicy",
    "allowedAttributes" : [ "java.util.ArrayList", [ "system_type", "user_type" ] ]
  }
}

    The above application definition is instructed to process claims assigned to standard scopes email, profile and openid, and will also release system_type and user_type as claims regardless of the scopes requested by the relying party.

  • It is possible to control the release of standard claims, i.e. name, that are connect to a standard scope, such as profile. Typically when the release policy references a standard scope, all claims available and resolved that belong to that scope are then released to the relying party. The configuration below allows direct and fine-tuned control over the set of claims that could be released as part of the larger claim bundle that is tied to a standard scope.

    

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    {
  "@class": "org.apereo.cas.services.OidcRegisteredService",
  "clientId": "client",
  "clientSecret": "secret",
  "serviceId": "...",
  "name": "Sample",
  "id": 1,
  "supportedGrantTypes": [ "java.util.HashSet", [ "authorization_code" ]],
  "supportedResponseTypes": [ "java.util.HashSet", [ "code" ]],
  "attributeReleasePolicy": {
    "@class": "org.apereo.cas.services.ChainingAttributeReleasePolicy",
    "policies": [ "java.util.ArrayList",
      [
        {
          "@class": "org.apereo.cas.oidc.claims.OidcProfileScopeAttributeReleasePolicy",
          "allowedAttributes" : [ "java.util.ArrayList", [ "locale", "name" ] ]
        },
        {
          "@class": "org.apereo.cas.oidc.claims.OidcEmailScopeAttributeReleasePolicy",
          "allowedAttributes" : [ "java.util.ArrayList", [ "email" ] ]
        }
      ]
    ]
  }
}

    If all claims available to the profile and email scopes are resolved and available to CAS for attribute release, the configuration above will only authorize the release of locale, name and email out of the entire set of available claims.

To learn more about attribute release policies and the chain of command, please see this guide.