Re: [Txauth] Claims [was: - Dictionary]

[Justin Richer <[e-mail]>]

Since we’re already talking about returning claims as direct data as well as a part of the resource API being protected, so we already need a way to differentiate the two kinds of items. Just calling it “claims” doesn’t help, because as you’ve pointed out they could show up in both places. So yes, defining that difference is something we should worry about now, even if the core protocol only uses it for claims.

The two forms of direct data that XYZ returns are subject identifiers (a subset of identity claims) and assertions — the latter being a container not just for identity claims but also authentication information and other elements. Assertions are not claims themselves. 

Other use cases that have been brought up include verifiable credentials and proofs, user-bound keys, payment processing information, and distributed network storage locations. I’m sure there are a lot more. To me, these are subsets of the “direct data” but not subsets of “claims”. GNAP shouldn’t be defining what all of these look like, but it should define a way to talk about them.

I think different top-level request objects are better suited for different query semantics. Like, for example, the OIDC “claims” request, which allows targeting of its claims information into different return buckets. This overlaps with the “resources” request at the very least. I don’t think GNAP should define how to do this specific combination, that should be for OIDF to debate and apply. The same with a DID service based query, or Presentation Exchange [1], or anything else that people want to come up with.

In my view, GNAP should define query structures for two things: rights that get tied to an access token and data that comes back directly to the client. For the latter, I think we can do some very limited and very useful specific items, which is what I’ve put into XYZ.

 — Justin

[1] https://identity.foundation/presentation-exchange/

> On Jul 24, 2020, at 3:58 PM, Dick Hardt <[e-mail]> wrote:
> 
> I agree we want GNAP to be a strong foundation. 
> 
> Do you have an example of other "direct data"? If so, do you expect it to be defined in the core protocol?
> 
> I would expect an extension for other "direct data" to define top level objects, and an appropriate definition for that "direct data".
> 
> My "do we need to worry about it now" comment was on creating a generic term for "direct data". Unless we are solving those now, we can let further work define that "direct data" explicitly.
> 
> 
> 
> 
> ᐧ
> 
> On Fri, Jul 24, 2020 at 12:42 PM Justin Richer <[e-mail] <mailto:[e-mail]>> wrote:
> Yes, I do think we need to worry about it to the extent that we are not creating something that is over-fit to a limited set of use cases. 
> 
> GNAP should be a foundation that many amazing new things can be built on top of.
> 
>  — Justin
> 
>> On Jul 24, 2020, at 3:06 PM, Dick Hardt <[e-mail] <mailto:[e-mail]>> wrote:
>> 
>> Justin, thanks for clarifying.
>> 
>> What are some examples of other "direct data" that the GS may return? If it is not in core GNAP, do we need to worry about now? We can then give the direct data from the GS that is not a claim, an appropriate name in that document.
>> 
>> 
>> 
>> On Fri, Jul 24, 2020 at 11:46 AM Justin Richer <[e-mail] <mailto:[e-mail]>> wrote:
>> Dick: No, I think you’re misunderstanding what I’m saying. I agree that “claims” are about the user, in this context*. But the AS could return other data directly to the client that isn’t about the user. Those aren’t “claims” by the classical definition. Also since “claims” can come back from places other than directly, then we shouldn’t call everything that comes back a “claim”.
>> 
>> I’m arguing that we keep “claims” to mean what it already means and come up with a new word to mean “things that come back directly from the AS”. These aren’t meant to replace Francis’s more complete definitions, but to simplify:
>> 
>> Claims:
>> 	- information about the user
>> 	- can come back directly from the AS
>> 	- can come back in a resource from the RS
>> 
>> Resource:
>> 	- Returned from an RS
>> 	- Protected by access token
>> 	- Could contain claims about the user
>> 
>> Direct data (or some better name):
>> 	- Returned directly from AS
>> 	- Could contain claims about the user
>> 
>> I think the problem is that some people are using “claims” to mean #1 and some to mean #3. It’s clearly #1 in OIDC. But: It’s important to remember, when talking about OIDC, that an IdP in OIDC combines an AS and an RS into one entity for identity information. There can be other RS’s as well, and there usually are in the wild, but the one defined by OIDC is the UserInfo Endpoint. The fact that it returns user data doesn’t make it any less of an RS.
>> 
>>  — Justin
>> 
>> * In the wider context of things like the information claims inside a JWT, the claims could be about literally anything, but that’s not what we’re discussing here and it’s not how it’s being used.
>> 
>> 
>>> On Jul 24, 2020, at 1:24 PM, Dick Hardt <[e-mail] <mailto:[e-mail]>> wrote:
>>> 
>>> In OpenID Connect (OIDC), the Client can obtain Claims directly from the OP in an ID Token, or the Client can obtain Claims using an access token to call the UserInfo endpoint, a Protected Resource[1].
>>> 
>>> The Claims are about the User (not a RO).
>>> 
>>> In XAuth, I'm proposing the Client may obtain bare claims from the GS directly in addition to the mechanisms in ODIC.
>>> 
>>> So I don't think we are changing the definition of Claim from how it has been used in OIDC, and I fail to see any reason to NOT use Claim.
>>> 
>>> Justin: you allude to Claims being about a party other than the User. Would you provide an example?
>>> 
>>> /Dick
>>> 
>>> [1]
>>> UserInfo Endpoint
>>> Protected Resource that, when presented with an Access Token by the Client, returns authorized information about the End-User represented by the corresponding Authorization Grant. The UserInfo Endpoint URL MUST use the https scheme and MAY contain port, path, and query parameter components.
>>> 
>>> 
>>> 
>>> ᐧ
>>> 
>>> On Fri, Jul 24, 2020 at 5:58 AM Justin Richer <[e-mail] <mailto:[e-mail]>> wrote:
>>> I want to focus on one aspect here:
>>> 
>>>> 
>>>> A Claim is a well understood term in the field. We should use it. It is still a Claim if it comes directly from the GS or from an RS. 
>>>> I do not understand why a Resource release by an RS shall be h to as a claim, even if the content of the Resource is an assertion. It will lead to confusion. If we limit claims to information GS releases into Token, User Info, and other objects it returns, this will help separate responsibilities between GS and RS. As soon as RS services and information, this is called a Resource, no matter the nature of the content of that information.
>>> 
>>> This is exactly why I don’t think we should use “claim” in the way that we’re using it. Yes, a “claim” could come back through an RS — but in the context of GNAP, that makes it a resource. So we need a different word for data coming back directly from the AS to the client. Sometimes it’s going to be about the user, and that’s what we’re going to focus on here, but since you can also get information about the user from a resource we can’t just call it a “claim”. I think this has been at the heart of a lot of confusion in recent threads, as well as confusion about the scope of the inclusion of identity in the GNAP protocol.
>>> 
>>> So let’s let “claim” mean what it already does, and let’s find a way to differentiate between when an item, claim or otherwise,  comes as part of a resource and when it comes back directly. This is an important differentiating feature for GNAP.
>>> 
>>> Some straw man ideas, none of which I’m particularly in love with:
>>> 
>>>  - direct data
>>>  - properties
>>>  - details
>>>  - statements
>>> 
>>> The important thing here is that it’s not necessarily :about: the RO, and that it is :not: in a resource.
>>> 
>>> Any other thoughts?
>>> 
>>>  — Justin
>> 
>