Skip to main content

Shepherd writeup

# Document Shepherd Write-Up for Group Documents

*This version is dated 4 July 2022.*

Thank you for your service as a document shepherd. Among the responsibilities is
answering the questions in this write-up to give helpful context to Last Call
and Internet Engineering Steering Group ([IESG][1]) reviewers, and your
diligence in completing it is appreciated. The full role of the shepherd is
further described in [RFC 4858][2]. You will need the cooperation of the authors
and editors to complete these checks.

Note that some numbered items contain multiple related questions; please be sure
to answer all of them.

## Document History

1. Does the working group (WG) consensus represent the strong concurrence of a
   few individuals, with others being silent, or did it reach broad agreement?

This document spent a couple years in the working group, and got feedback from many
contributors, both from people specifically interested in signatures, as well as
the people involved in generic HTTP. It received quite careful review and I sense
it has broad agreement. The WGLC didn't receive many specific email responses, but
there was sufficient discussion on GitHub and in the meeting to confirm consensus.

2. Was there controversy about particular points, or were there decisions where
   the consensus was particularly rough?

At IETF 114, there was concern raised (by Chris Wood) that there should be more formal
analysis performed, akin to the process normally used in CFRG. This document was then
presented at IETF 115 in SAAG for broad discussion of formal analysis as well as to
get specific feedback on this document. The sense of that room was that formal
analysis was not a gating factor that is present for security documents, and the comments
about this document were positive. Separately, an academic formal analysis is ongoing,
but the chairs have decided to progress this document to the IETF and IESG in parallel
with that work.

3. Has anyone threatened an appeal or otherwise indicated extreme discontent? If
   so, please summarize the areas of conflict in separate email messages to the
   responsible Area Director. (It should be in a separate email because this
   questionnaire is publicly available.)

No appeals or extreme discontent expressed.

4. For protocol documents, are there existing implementations of the contents of
   the document? Have a significant number of potential implementers indicated
   plans to implement? Are any existing implementations reported somewhere,
   either in the document itself (as [RFC 7942][3] recommends) or elsewhere

There are many implementations of earlier versions of signatures, and this version
has also received implementation and interop testing, which has been discussed and presented
to the working group. (Note that this is not documented in the document itself.)

## Additional Reviews

5. Do the contents of this document closely interact with technologies in other
   IETF working groups or external organizations, and would it therefore benefit
   from their review? Have those reviews occurred? If yes, describe which
   reviews took place.

This document mainly overlaps with security area. It received an early SecDir
review last year, as well as extra reviews in the past month by security area
reviewers (such as Kyle Rose).

6. Describe how the document meets any required formal expert review criteria,
   such as the MIB Doctor, YANG Doctor, media type, and URI type reviews.

None of the above apply. The document does add HTTP field registrations, but this
working group is appropriate to review those.

7. If the document contains a YANG module, has the final version of the module
   been checked with any of the [recommended validation tools][4] for syntax and
   formatting validation? If there are any resulting errors or warnings, what is
   the justification for not fixing them at this time? Does the YANG module
   comply with the Network Management Datastore Architecture (NMDA) as specified
   in [RFC 8342][5]?


8. Describe reviews and automated checks performed to validate sections of the
   final version of the document written in a formal language, such as XML code,
   BNF rules, MIB definitions, CBOR's CDDL, etc.

This document does use ABNF, which has been checked and validated.

## Document Shepherd Checks

9. Based on the shepherd's review of the document, is it their opinion that this
   document is needed, clearly written, complete, correctly designed, and ready
   to be handed off to the responsible Area Director?

The document is clearly written in my opinion, and ready for hand-off.

10. Several IETF Areas have assembled [lists of common issues that their
    reviewers encounter][6]. For which areas have such issues been identified
    and addressed? For which does this still need to happen in subsequent

SecDir review has been conducted, as earlier noted.

11. What type of RFC publication is being requested on the IETF stream ([Best
    Current Practice][12], [Proposed Standard, Internet Standard][13],
    [Informational, Experimental or Historic][14])? Why is this the proper type
    of RFC? Do all Datatracker state attributes correctly reflect this intent?

Proposed Standard, as this specifies a standard version of HTTP message signatures
(distinct from previous non-standard versions). The datatracker state and document
state are consistent.

12. Have reasonable efforts been made to remind all authors of the intellectual
    property rights (IPR) disclosure obligations described in [BCP 79][7]? To
    the best of your knowledge, have all required disclosures been filed? If
    not, explain why. If yes, summarize any relevant discussion, including links
    to publicly-available messages when applicable.

Authors and others have not disclosed any relevant IPR.

13. Has each author, editor, and contributor shown their willingness to be
    listed as such? If the total number of authors and editors on the front page
    is greater than five, please provide a justification.

Yes, the authors (3) are active in participation.

14. Document any remaining I-D nits in this document. Simply running the [idnits
    tool][8] is not enough; please review the ["Content Guidelines" on][15]. (Also note that the current idnits tool generates
    some incorrect warnings; a rewrite is underway.)

Current nits are only around normative downrefs, see below.

15. Should any informative references be normative or vice-versa? See the [IESG
    Statement on Normative and Informative References][16].


The following are listed as downrefs, but are part of the downref registry
( and should be thus accepted.

  ** Downref: Normative reference to an Informational RFC: RFC 2104
  ** Downref: Normative reference to an Informational RFC: RFC 6234
  ** Downref: Normative reference to an Informational RFC: RFC 8017
  ** Downref: Normative reference to an Informational RFC: RFC 8032

The following is a downref to a document also normatively referenced
in RFC 8292 and should be accepted:

  -- Possible downref: Non-RFC (?) normative reference: ref. 'FIPS186-4'

The following is a downref that may not have other examples, but the
authors and chairs believe is an acceptable downref:

  -- Possible downref: Non-RFC (?) normative reference: ref. 'HTMLURL'

16. List any normative references that are not freely available to anyone. Did
    the community have sufficient access to review any such normative

The normative references are available publicly.

17. Are there any normative downward references (see [RFC 3967][9] and [BCP
    97][10]) that are not already listed in the [DOWNREF registry][17]? If so,
    list them.

If the registry can contain non-RFC documents, we should consider adding
the FIPS186-4 and HTMLURL references.

18. Are there normative references to documents that are not ready to be
    submitted to the IESG for publication or are otherwise in an unclear state?
    If so, what is the plan for their completion?

No normative references to Internet Drafts.

19. Will publication of this document change the status of any existing RFCs? If
    so, does the Datatracker metadata correctly reflect this and are those RFCs
    listed on the title page, in the abstract, and discussed in the
    introduction? If not, explain why and point to the part of the document
    where the relationship of this document to these other RFCs is discussed.

No, this document does not change any RFC status.

20. Describe the document shepherd's review of the IANA considerations section,
    especially with regard to its consistency with the body of the document.
    Confirm that all aspects of the document requiring IANA assignments are
    associated with the appropriate reservations in IANA registries. Confirm
    that any referenced IANA registries have been clearly identified. Confirm
    that each newly created IANA registry specifies its initial contents,
    allocations procedures, and a reasonable name (see [RFC 8126][11]).

The IANA registry changes look correct.

21. List any new IANA registries that require Designated Expert Review for
    future allocations. Are the instructions to the Designated Expert clear?
    Please include suggestions of designated experts, if appropriate.

This creates the following new registries:
HTTP Signature Algorithms Registry
HTTP Signature Metadata Parameters Registry
HTTP Signature Derived Component Names Registry
HTTP Signature Component Parameters Registry

All use Expert Review as their process. The authors or other HTTPbis WG contributors
would be good candidates for acting as the experts.