The author approved the draft with its recommendations, decision 8 among
them: section 12.1 admits only the scheme whose verification and tlock
decryption the text now writes byte for byte. profile.Validate refuses the
other two unchained schemes of drand with ERR_UNKNOWN_PROFILE. No pinned
profile and no vector changes; section 76 records it as change 7.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Amendment of the unreleased v0.8.2, recorded in §76 with its case: the
second implementation's phase-2 research found that tlock-js over
@noble/curves 1.9.7 accepts U re-encoded as c0 + p and a signature
x + p and returns the same file key, while the reference rejects both
(noble 1.9.7 differed from kilic on 5,615 of 41,686 encodings), and the
spec did not say which encodings are valid.
- §12.2 defines the canonical encoding of a BLS12-381 point (drand's
compressed ZCash form) and requires decoders to reject every other
byte string; §12.1 applies it to public_key.
- §63 step 10 applies it to the release signature (ERR_RELEASE_INVALID)
and step 11 defines the tlock stanza body U || V || W (96 + 16 + 16
bytes for Quicknet) with a canonical, non-infinity U (ERR_INTEGRITY).
- §64 gains ten mutations, exported to mutations.json (65 cases). The
signature x + p case uses published Quicknet round 1004, the first
after 1000 whose x allows x + p < 2^381. The reference already gave
every stated code and step.
Errors no longer copy text from tlock, kyber, age, drand or
kyber-bls12381. kyber's IBE error carried the candidate plaintext and r,
and with one bit of W flipped the message disclosed the real tlock file
key with that bit flipped. Every such place now uses a fixed reason with
its normative sentinel; TestTlockFailureDiagnosticsCarryNoSecrets fails
with the old wrapping.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Approved refinements, each recorded with its reproducible case in the
§76 v0.8.2 subsection:
- §69.1: layered error model with normative precedence (frame, type tag
and version, CBOR profile and CDDL, then fields with their own code in
ascending key order; across steps the §63 order decides), with a scope
paragraph for the optional steps 5, 6 and 8.
- §55.1: normative trust table per section (who can write it, from which
step it is bound, what it never proves); §72: security-relevant claims
go in CONTROL_CBOR or under a signature, .dkk data is advisory.
- §31/§54: extension arrays in strictly ascending unsigned byte order of
extension_id (one rule for order and uniqueness).
- Gaps a second implementation needed: §28.1 malformed age headers,
§15/§19 latest unlock time and dk1_ reading rules, §22/§23/§57 length
lower bounds, §63 step 8 tlock argument comparison and step 9 order,
§12.1 profile validation with the drand chain-hash formula, §74 table
of implementation limits.
Reference alignment: .dkk errors only at step 9.a (new
OpenOptions.AccessKeyFile, used by the CLI), CR/LF in dk1_ is
ERR_DATEKEY_INVALID, BODY_LEN 0 is ERR_INTEGRITY, nil identities are not
credentials, and AccessIdentity tries every identity on every stanza so
its verdict does not depend on their order. dk1.json gains three
vectors; every other testdata file is byte-identical.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>