How to return the appropriate Attributes with CAS acting as SAML IdP and SAML SP in the same instance

[JON]

Hi there, here is my challenge

We can work in two SAML integration ways, by means of CAS.5.2 in the same instance of CAS over Tomcat.

• In one way (A), our Identity Provider launches a SSO SAML Request, delegating Authentication in CAS. CAS, in turn, delegates Authentication to a third party SAML Identity Provider. At the end, in the return way, a User Session in created in our Identity Provider, with diverse Identity Attributes.

Our IdP => [in SAML SP role] SSO SAML Request => CAS SAML IdP => [in SAML SP role] SSO SAML Request => Third Party SAML IdP

• In another way (B), CAS receives SSO SAML Requests made by third party SAML Service Providers, where CAS delegates authentication in our proprietary Trusted Identity Provider (with which, CAS has a Trusted Authentication defined). In that way, our Identity Provider creates a User Session, with diverse Identity Attributes, which returns to CAS, and this propagates to the third party SAML Service Provider.

Third Party SAML SP => SSO SAML Request => CAS IdP => Trusted Authentication => Our Proprietary IdP

 

Putting it all together, we have a mixed stage in which:

1.- User is authenticated by a third party SAML Identity Provider, by means of the (A) way

After that, in the next instant

2.- User accesses a third party SAML Service Provider, trying to obtain our Identity Provider’s User Session Identity Attributes in (B) way

Instead, CAS returns, to the third party SAML Service Provider, the User Attributes obtained in (A) from the third party SAML Identity Provider.

What we need is to propagate, in (B) way, our Identity Provider’s User Session Identity Attributes, obtained at the end of the (A) way flow.

I think that separating the two flows in two separate CAS instances, all would start to work, but that’s not the challenge.

Thanks for your time and interest

Jon

[Ray Bon]

Jon,

You could get all attributes from your IdP and third party IdP on first login.

Once cas has established a session (TGC) it no longer attempts to create new user attributes.

Two cas servers would mean no sso.

Can you remove your IdP and let cas to its work?

Ray

On Thu, 2021-07-08 at 00:43 -0700, JON wrote:

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[JON]

Thank you very much Ray

On first Login, CAS obtains the attributes from the third party SAML IdP, not from our IdP. As you say, after that, it does’nt try to add new attributes.

I’ve tried to use the following in SamlRegisteredService’s, but doesn’t resolve the problem

"attributeReleasePolicy" : {

    "@class" : "org.apereo.cas.services.ReturnAllAttributeReleasePolicy",

    "principalIdAttribute": "id",

    "authorizedToReleaseAuthenticationAttributes": true,

    "excludeDefaultAttributes": false,

    "principalAttributesRepository" : {

      "@class" : "org.apereo.cas.authentication.principal.cache.CachingPrincipalAttributesRepository",

      "duration" : {

        "@class" : "javax.cache.expiry.Duration",

        "timeUnit" : [ "java.util.concurrent.TimeUnit", "MILLISECONDS" ],

        "expiration" : 100

      },

      "mergingStrategy" : "ADD"

    }

  }

 

The SSO is maintained in our IdP. CAS help us to Trust/Federate/Integrate with third party Identity & Service Providers by means of standards like SAML. Remove our IdP is not an option.

May be what I need is exactly the opposite, forgetting the result of the first SAML SSO Delegation, it would act as if the Trusted Integration is the first Integration act.

But don’t know how to do it.

 

Thanks

            Jon

[Ray Bon]

Jon,

You can disable sso, globally or per service, https://apereo.github.io/cas/6.3.x/installation/Configuring-SSO.html#disable-sso-globally

Ray