Thanks Chris and David,

Those sound like great changes that will help this document pass through
ACME WG review!



This comment caught my eye:
> the server only needs to verify that the value in the token matches the
value in the order.

I'm assuming that's referring to Section 6, Step 5?

"Verify Constraints Match: Verify that the "atc" claim "tkvalue" identifier
contains the equivalent base64url encoded JWTClaimConstraints or
EnhancedJWTClaimConstraints certificate extension string value as the
Identifier specified in the original challenge."
?
I've been recently re-familiarized with RFC6943 which details all the ways
that CVEs hide in the gaps of under-specified equality checking
procedures for identifiers, so I want to poke at whether "equivalent
base64url ... string value" is tightly-specified enough to prevent a ...
umm ... clever implementer from "clever'ing" themselves into a
vulnerability, or if the equality check algorithm could be spelled out more
explicitly? When talking about comparing two identifiers, I generally
expect to see some variant of the text: "Do blah blah to put both
identifiers into their canonical form, then perform a byte-by-byte
comparison".

On Thu, 26 Mar 2026 at 07:48, Chris Wendt <chris=
[email protected]> wrote:

> Hi ACME WG,
>
> We were unfortunately unable to attend IETF 125 and wanted to follow up on
> list with an update to the document following the discussion at IETF 124
> and subsequent editorial review.
>
> The updated draft addresses the feedback from the meeting, particularly
> Aaron's observation that the ACME wire protocol sections are clear but the
> validation description was difficult to review without STIR ecosystem
> background. The changes are summarized below.
>
> Substantive changes:
>
> The Introduction now includes a short paragraph orienting ACME reviewers
> to the STI ecosystem context — noting that this document follows the same
> pattern as the TNAuthList profile (RFC 9448) and that the Token Authority
> is responsible for the domain-specific semantic validation of
> JWTClaimConstraints content governed by RFC 8226 and RFC 9118.
>
> Section 6 now includes a framing note that explicitly identifies which
> validation steps are generic ACME authority token steps and which two steps
> are specific to this profile. This should allow ACME reviewers to scope
> their review without needing deep familiarity with the STIR certificate
> extensions.
>
> The ASN.1 examples of JWTClaimConstraints structures that were previously
> in the normative body of Section 5.5 have been moved to an informative
> Appendix A. Section 5.5 now includes a brief paragraph clarifying that the
> identifier value is opaque from the ACME server's perspective — the server
> only needs to verify that the value in the token matches the value in the
> order. The appendix retains the full ASN.1 examples including DER encodings
> and base64url values for STI Token Authority and certificate requestor
> implementers.
>
> Editorial changes:
>
> Fixed broken normative references in the Introduction, corrected a JSON
> syntax error in the authorization object example, normalized JSON/JWT
> indentation and colon spacing consistently across all code blocks, fixed
> the challenge response URL in the protected header example, and added
> clarifying notes around the Token Authority account identifier and the flow
> back to the ACME challenge URL after token acquisition.
>
> We believe the document is in good shape for review. Feedback welcome on
> list.
>
> Thanks,
> Chris & David
>
>
> > On Mar 26, 2026, at 8:45 AM, [email protected] wrote:
> >
> > Internet-Draft draft-ietf-acme-authority-token-jwtclaimcon-01.txt is now
> > available. It is a work item of the Automated Certificate Management
> > Environment (ACME) WG of the IETF.
> >
> >   Title:   JWTClaimConstraints profile of ACME Authority Token
> >   Authors: Chris Wendt
> >            David Hancock
> >   Name:    draft-ietf-acme-authority-token-jwtclaimcon-01.txt
> >   Pages:   21
> >   Dates:   2026-03-26
> >
> > Abstract:
> >
> >   This document defines an authority token profile for the validation
> >   of JWTClaimConstraints and EnhancedJWTClaimConstraints certificate
> >   extensions within the Automated Certificate Management Environment
> >   (ACME) protocol.  This profile is based on the Authority Token
> >   framework and establishes the specific ACME identifier type,
> >   challenge mechanism, and token format necessary to authorize a client
> >   to request a certificate containing these constraints.
> >
> > The IETF datatracker status page for this Internet-Draft is:
> >
> https://datatracker.ietf.org/doc/draft-ietf-acme-authority-token-jwtclaimcon/
> >
> > There is also an HTMLized version available at:
> >
> https://datatracker.ietf.org/doc/html/draft-ietf-acme-authority-token-jwtclaimcon-01
> >
> > A diff from the previous version is available at:
> >
> https://author-tools.ietf.org/iddiff?url2=draft-ietf-acme-authority-token-jwtclaimcon-01
> >
> > Internet-Drafts are also available by rsync at:
> > rsync.ietf.org::internet-drafts
> >
> >
> > _______________________________________________
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> > To unsubscribe send an email to [email protected]
>
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