[OAUTH-WG] Re: I-D Action: draft-ietf-oauth-status-list-11.txt

[Paul Bastian <[e-mail]>]

Hi Denis,

I've responded to your issues in detail in this Github issue: 
https://github.com/oauth-wg/draft-ietf-oauth-status-list/issues/294

I also copied my answers inline as well.

A PR will follow later today.

Best regards, Paul

On 6/9/25 09:06, Denis wrote:
> Hi Rifaat,
>
> I have 10 comments.
>
> 1) There are still a few vocabulary issues that relate to confusion 
> between "Token Status Lists" and "Status List Tokens".
>    This is addressed in subsequent comments.
>
>
> 2) The title of the document is "Token Status List". There is no 
> single "Token Status List".
>     The goal of this document is to allow the retrieval of Status List 
> Tokens, where each Status List Token (SLT)
>     contains a Token Status List that provides up-to-date status 
> information on several Referenced Tokens.
>
>    The acronym "SLT" should be introduced in the document, in the same 
> way as the acronym "CRL"
>     has been introduced for "Certificate Revocation List" (RFC 5280).
>
>    The title of this document should rather be: Status List Tokens (SLTs)

The name "Token Status List" of the draft makes sense:

  * the naming is similar to Certificate Revocation List - read:
    Revocation List for Certificates, here the same: Status List for Token
  * Token is a very common term in the OAuth ecosystem, similar to
    "Certificate", so the naming sequence is exactly the same as CRL
  * the Status List Token is still its own thing, it's defined in the
    section 5 and covers how a Status List structure from Section 4 is
    integrty/authenticity-protected, however a Status List Token is
    usually not relevant from the high-level outside look

Conclusion:

  * I agree that it makes sense to establish an official abbreviation
    like CRL
      o I think that TSL makes more sense
  * Status List Token should remain as an internal terminology apart
    from TSL

>
>
> 3) The current text in section 6.1 (Status Claim) is:
>
>        By including a "status" claim in a Referenced Token, the Issuer is
>        referencing a mechanism to retrieve status information about this
>        Referenced Token.  The claim contains members used to reference a
>        Status List Token as defined in this specification.  Other
>     members of
>        the "status" object may be defined by other specifications.
>
>    In this specification, only one member of the "status" object is 
> defined.
>    Taking into account the previous comment, I propose to rephrase 
> these sentences as follows:
>
>        By including a "status" claim in a Referenced Token, the Issuer
>     can
>        indicate in a "status" object, how status information about a
>        Referenced Token can be obtained.  This specification defines one
>        member of the "status" object, called "status_list".  Other
>     members of
>        the "status" object may be defined by other specifications.
>
Partly accepted
> 4) The examples in sections 6.2 and 6.1 are confusing "status lists" 
> with "status list tokens".
>
> The current text in section 6.2 ( Referenced Token in JOSE) is:
>
>        The following is a non-normative example of a decoded header and
>        payload of a Referenced Token:
>
>        {
>          "alg": "ES256",
>          "kid": "11"
>        }
>        .
>        {
>          "status": {
>            "status_list": {
>              "idx": 0,
>              "uri": "https://example.com/statuslists/1"
>            }
>          }
>        }
>
>
>    The uri does not contain "statuslists" (status lists) but "slts" 
> (Status List Tokens).
>    The uri should be changed into the following way:
>
>          "uri": "https://example.com/slts/1"
>
>    The same comment applies to the example on page 22 within section 
> 6.3 (Referenced Token in COSE).
The URI is a non-normative example, so I don't believe it is relevant. 
If other group members think this is important, we may change this.
>
>
> 5) The current text in section 9 (Status List Aggregation) is:
>
>     9.  Status List Aggregation
>
>        Status List Aggregation is an optional mechanism to retrieve a
>     list
>        of URIs to all Status List Tokens, allowing a Relying Party to
>     fetch
>        all relevant Status List Tokens for a specific type of Referenced
>     Token or Issuer.  This mechanism is intended to support fetching and
>        caching mechanisms and allow offline validation of the status of a
>        reference token for a period of time.
>
>     The wording "for a specific type of Referenced Token or Issuer" 
> should be avoided because the retriever of the SLTs
>     has no way to know whether the retrieved SLTs will be about a 
> "specific type of Referenced Token", about "all the Referenced Tokens
>     issued by that Issuer" or about anything else. Depending upon 
> choices made by the Issuer, the retrieved SLTs may help or
>     *may not help* the Relying Party, depending upon the context and 
> the choices made by the Issuer.
>
> The following rewording is proposed:
>
>     9.  Status List Aggregation
>
>     Status List Aggregation is an optional mechanism that allows to
>     take advantage of an access to a given Status List Token
>     referenced in a Referenced Token to retrieve other Status List
>     Tokens published by the same Issuer.
>     This feature is intended to support pre-fetching and caching of
>     Status List Tokens and allows offline validation of the status
>     of further received Reference Tokens for a period of time.
>

The Section 9 on Status List Aggregation lists two mechanisms:

    There are two options for a Relying Party to retrieve the Status
    List Aggregation. An Issuer MAY support any of these mechanisms:

    Issuer metadata: The Issuer of the Referenced Token publishes an URI
    which links to Status List Aggregation, e.g. in publicly available
    metadata of an issuance protocol

    Status List Parameter: The Status Issuer includes an additional
    claim in the Status List Token that contains the Status List
    Aggregation URI.

So while the Relying Party may not know whether an Issuer uses a 
particular Status List Aggregation to link /all/ Status Lists or only 
for a specific type of Referenced Token, an Issuer has still the choice 
to do so, therefore the text is correct in my opinion. Your proposed 
text removes functionality that does not match the rest of Section 9.

>
> 6) The text continues with:
>
>        "If a Relying Party encounters an invalid Status List
>     referenced in
>        the response from the Status List Aggregation endpoint, it SHOULD
>        continue processing the other valid Status Lists referenced in the
>        response instead of fully aborting processing and retrying later".
>
>    This sentence is misleading: the Status List Aggregation endpoint 
> does not contain "Status Lists" but contains "Status List Tokens".
>    If corrected the quoted sentence, the sentence would become:
>
>        If a Relying Party encounters an invalid Status List Token
>     referenced
>        in the response from the Status List Aggregation endpoint, it
>     SHOULD
>        continue processing the other valid Status List Tokens
>     referenced in
>        the response instead of fully aborting processing and retrying
>     later.
>
>    However, when fetching the Status List Tokens, the pre-fetching and 
> caching mechanism does not *mandate* any "validation mechanism",
>    hence the concept of an " invalid Status List" or of an " invalid 
> Status List Token" is irrelevant. The goal of this mechanism is to allow
>    fetching SLTs and to place them into a cache without *necessarily* 
> verifying their "validity" at the moment of the retrieval.
>    I propose to remove that sentence.
You are correct that it is slightly better to say Status List Token 
here. Apart from this, I believe that validation at caching time makes 
sense. There are multiple options ins COSE and JOSE that require 
fetching additional resources, like |kid| for |x5u|, that wouldn't work 
if you only pre-fetch Status List Tokens without validation?
>
>
> 7) Section 9.3 (Status List Aggregation in JSON Format) states:
>
>     9.3.  Status List Aggregation in JSON Format
>
>        This section defines the structure for a JSON-encoded Status List
>        Aggregation:
>
>        *  status_lists: REQUIRED.  JSON array of strings that contains
>     URIs
>           linking to Status List Tokens.
>
>        The Status List Aggregation URI provides a list of Status List
>     URIs.
>
>        (...)
>
>        The following is a non-normative example for media type
>     application/
>        json:
>
>        {
>           "status_lists" : [
>              "https://example.com/statuslists/1",
>              "https://example.com/statuslists/2",
>              "https://example.com/statuslists/3"
>           ]
>        }
>
>
>    Given the confusion between "Status Lists" and "Status List 
> Tokens", the text from this section should be modified.
>    Below is a proposal:
>
>     9.3.  Status List Aggregation in JSON Format
>
>        This section defines the structure for a JSON-encoded Status List
>        Aggregation:
>
>        *  status_lists: REQUIRED.  JSON array of strings that contains
>     URIs
>           linking to Status List Tokens.
>
>        The Status List Aggregation URI provides a list of Status List
>     *Token* URIs.
>
>        (...)
>
>        The following is a non-normative example for media type
>     application/
>        json:
>
>        {
>           "status_lists" : [
>              "https://example.com/slts/1",
>              "https://example.com/slts/2",
>              "https://example.com/slts/3"
>           ]
>        }
>
Accepted
>
> 8) Section 13.1 (Token Lifecycle) states:
>
>     13.1.  Token Lifecycle
>
>        The lifetime of a Status List Token depends on the lifetime of its
>        Referenced Tokens.  Once all Referenced Tokens are expired, the
>        Issuer may stop serving the Status List Token.
>
>        Referenced Tokens may be regularly re-issued to mitigate the
>        linkability of presentations to Relying Parties.  In this case,
>     every
>        re-issued Referenced Token MUST have a fresh Status List entry in
>        order to prevent this from becoming a possible source of
>     correlation.
>
>        Referenced Tokens may also be issued in batches and be
>     presented by
>        Holders in a one-time-use policy to avoid linkability.  In this
>     case,
>        every Referenced Token MUST have a dedicated Status List entry and
>        MAY be spread across multiple Status List Tokens.  Revoking batch-
>        issued Referenced Tokens might reveal this correlation later on.
>
>    The use of the sub-title 13.1 "Token Lifecycle " is confusing as it 
> can apply either to "Referenced Tokens" or to "Status List Tokens".
>    The first sentence applies to "Status List Token Lifecycle" but the 
> next sentences apply to linkability issues using indexes contained
>    in Status List Tokens. I propose to separate these two cases.
>
> The following text is proposed:
>
>     13.1.  Status List Token Lifecycle
>
>        The lifetime of a Status List Token depends on the lifetime of its
>        Referenced Tokens.  Once all Referenced Tokens from a Status
>     List Token
>        are expired, the Issuer may stop issuing the Status List Token.
>
>     13.2.  Linkability issues using indexes contained in Status List
>     Tokens
>
>        To mitigate the linkability of presentations of Referenced
>     Tokens to
>        Relying Parties using the index contained in a Status List Token,
>        batches of one-time-use Referenced Tokens should be issued by the
>        Issuer and each Referenced Tokens from the batch should only be
>     used
>        once by the Holder.
>
>        For each Referenced Token belonging to a batch of one-time-use
>        Referenced Tokens, the indexes in the Status List should not be
>        placed into the same Status List and hence into the same Status
>     List
>        Token, but spread among different Token Status Tokens.  In this
>     way,
>        if the status of a batch of one-time-use Referenced Token changes
>        simultaneously, it will be difficult to know whether the
>     Referenced
>        Tokens belongs to a batch of one-time-use Referenced Tokens and to
>        which one.
>
Accepted to split the sections.
>
> 9) There is also an issue about the new IANA entries where the 
> "status" claim is defined
>     and where it is possible to place underneath the "status_list" entry.
>
>    The definition of the Claim Name "status" in section 14.1.1 
> includes the following sentence:
>
>        *  Claim Description: Reference to a status or validity mechanism
>           containing up-to-date status information on the JWT.
>
>    A status or a validity mechanism does not *contain* up-to-date 
> status information.
>    It *describes* how status information is provided for a given 
> Referenced Token.
>
>    I suggest to change this sentence into:
>
>        *  Claim Description: Reference to a status or validity mechanism
>           describing how status information about a Referenced Token can
>           be obtained.
>
Indeed the existing text is not ideal. I propose: "A JSON object 
containing a reference to a status mechanism from the JWT Status 
Mechanisms Registry."
> 10) Section 14.1.2 defines the Claim Name "status_list"
>
>     Claim Name: status_list
>
>        *  Claim Description: A status list containing up-to-date status
>           information on multiple tokens.
>
>    I propose to rephrase it in this way:
>
>     Claim Name: status_list
>
>        *  Claim Description: A status list contained in a Status List
>     Token
>           providing up-to-date status information on several Referenced
>           Tokens.
>
Indeed the existing text is not ideal. I propose: "A JSON object 
containing up-to-date status information on multiple tokens using the 
Token Status List mechanism."
>
> Denis
>
>> All,
>>
>> Please, review this version of the document and make sure that your 
>> comments, if you had any, were addressed.
>> I will start working on the shepherd write-up in a week or two.
>>
>> Regards,
>>  Rifaat
>>
>>
>> On Fri, May 23, 2025 at 5:05 AM <[e-mail]> wrote:
>>
>>     Internet-Draft draft-ietf-oauth-status-list-11.txt is now
>>     available. It is a
>>     work item of the Web Authorization Protocol (OAUTH) WG of the IETF.
>>
>>        Title:   Token Status List
>>        Authors: Tobias Looker
>>                 Paul Bastian
>>                 Christian Bormann
>>        Name:    draft-ietf-oauth-status-list-11.txt
>>        Pages:   72
>>        Dates:   2025-05-23
>>
>>     Abstract:
>>
>>        This specification defines a mechanism, data structures and
>>        processing rules for representing the status of tokens secured by
>>        JSON Object Signing and Encryption (JOSE) or CBOR Object
>>     Signing and
>>        Encryption (COSE), such as JWT, SD-JWT VC, CBOR Web Token and ISO
>>        mdoc.  It also defines an extension point and a registry for
>>     future
>>        status mechanisms.
>>
>>     The IETF datatracker status page for this Internet-Draft is:
>>     https://datatracker.ietf.org/doc/draft-ietf-oauth-status-list/
>>
>>     There is also an HTML version available at:
>>     https://www.ietf.org/archive/id/draft-ietf-oauth-status-list-11.html
>>
>>     A diff from the previous version is available at:
>>     https://author-tools.ietf.org/iddiff?url2=draft-ietf-oauth-status-list-11
>>
>>     Internet-Drafts are also available by rsync at:
>>     rsync.ietf.org::internet-drafts
>>
>>
>>     _______________________________________________
>>     OAuth mailing list -- [e-mail]
>>     To unsubscribe send an email to [e-mail]
>>
>>
>> _______________________________________________
>> OAuth mailing list [e-mail]
>> To unsubscribe send an email [e-mail]
>
>
>
> _______________________________________________
> OAuth mailing list [e-mail]
> To unsubscribe send an email [e-mail]