Re: [OAUTH-WG] JWT Response for OAuth Token Introspection and types of tokens

[Torsten Lodderstedt <[e-mail]>]

Hi Andrii,

> Am 07.02.2021 um 21:30 schrieb Andrii Deinega <[e-mail]>:
> 
> 
> Hi Torsten,
> 
> thank you for your response.
> 
> My use case is pretty straight forward
> 
> An OAuth client queries the AS to determine the active state of an access token and gets the introspection response which indicates that this access token is active (using RFC7662).
> 
> An OAuth client queries the AS to determine the active state of a refresh token and gets the introspection response which indicates that this refresh token is active (using RFC7662).
> 
> An OAuth client queries the AS to determine the active state of an access token and gets the introspection response (JWT) which indicates that this access token is active (using this draft).
> 
> Now, an OAuth client queries the AS to determine the active state of a refresh token (using this draft)... How will the introspection response look like assuming that the client provides the valid refresh token and technically, nothing stops it from doing so.

why should the state be provided as JWT?I think the plain JSON response is sufficient in that case.  I also think using token introspection for checking the state of a token from the client side has limited utility. The definitive decision is always made when the client tries to access a resource. 

I‘m therefore leaning towards explicitly stating in our draft that it is not intended to be used with refresh tokens.

best regards,
Torsten.

> 
> Regards,
> Andrii
> 
> 
>> On Sun, Feb 7, 2021 at 4:14 AM Torsten Lodderstedt <[e-mail]> wrote:
>> Hi Andrii,
>> 
>> thanks for your post. 
>> 
>> The draft is intended to provide AS and RS with a solution to exchange signed (and optionally encrypted) token introspection responses in order to provide stronger assurance among those parties. This is important in use cases where the RS acts upon the introspection response data and wants the AS to take liability re the data quality. 
>> 
>> I’m not sure whether there are similar use cases if a client introspects a refresh token. What is your use case?
>> 
>> best regards,
>> Torsten.  
>> 
>> > Am 07.02.2021 um 08:41 schrieb Andrii Deinega <[e-mail]>:
>> > 
>> > Hi WG,
>> > 
>> > draft-ietf-oauth-jwt-introspection-response-10 states that "OAuth 2.0 Token Introspection [RFC7662] specifies a method for a protected resource to query an OAuth 2.0 authorization server to determine the state of an access token and obtain data associated with the access token." which is true. Although, according to RFC7662, the introspection endpoint allows to introspect a refresh token as well. Hence, the question I have is how will a token introspection response look like when the caller provides a refresh token and sets the "Accept" HTTP header to "application/token-introspection+jwt"?
>> > 
>> > I expect there will be no differences, right?
>> > 
>> > If so, I suggest to
>> >       • replace "a resource server" by "the caller" in section 4 (Requesting a JWT Response)
>> >       • change "If the access token is invalid, expired, revoked" by "If a given token is invalid, expired, revoked" in section 5 (JWT Response)
>> > If not, my suggestion would be to clarify what the AS should do when it asked to introspect the refresh token in general and additionally, what should happen in the same case based on the type of the caller from the AS's point of view.
>> > 
>> > Regards,
>> > Andrii
>> > 
>>