The reference moves to the DateKeys Protocol Specification v0.9, approved
by its author on 29 September 2026. Encrypt writes capsule format 2 only;
Open and Inspect read formats 1 and 2, and a format 1 capsule keeps the
verdict v0.8.2 gave it.
Format 2 (spec §22, §29.1, §31, §39):
- VERSION in the PRELUDE is the capsule format, capsule.Format; any other
value is ERR_UNSUPPORTED_VERSION at step 2.
- CONTROL_CBOR has the schema version of its format. Version 2 adds key 6,
payload_length (8 bytes, big-endian, at most L_MAX = 2^53 - 2^46), and
key 7, padding (1 bloque256, 2 reforzado); it is 103 bytes without
extensions, whatever L.
- The payload is the content padded with zeros to P = rule(L). Step 17
checks the length and the zeros, and Open writes only the first L bytes.
- INNER_ACCESS_AGE holds exactly 16 X25519 stanzas: 1 to 16 credentials,
and a dummy in each slot left, in a uniformly random order.
Writer rules (spec §62.1): EncryptOptions.Length is required and the
source must deliver exactly that many bytes; recipients that are not
canonical or of low order are rejected (agewrap.CheckX25519Recipient);
self-checks of the header, the control, INNER_ACCESS_AGE and PAYLOAD_AGE.
The CLI measures its input, takes -padding and reports the format.
Test data: seven format 2 fixtures, padding vectors checked against
math/big, format 2 CBOR vectors, and the mutation corpus in both formats
with the 22 cases of the third list of spec §64, built without randomness
by sealing the fixtures again with their known keys and nonces. The
format 1 fixtures are kept byte for byte and never regenerated; the
differential corpus keeps its 1825 cases and adds a block per format 2
fixture. The spec copy loses its "to be implemented" markers, and the
READMEs, CHANGELOG, traceability and testdata/README.md follow v0.9.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- extension: data is an opaque []byte; New takes []byte and rejects empty
data; key 2 must be a non-empty shortest-form bstr; at most 64 extensions
per array; extension_version <= 2^32-1; CheckDisjoint is a linear merge;
optional DataValidator with ERR_EXTENSION_DATA_INVALID for known critical
extensions and Unusable reports for known noncritical ones.
- capsule, accesskey: frame limits on encode and decode with ERR_INTEGRITY;
Encrypt and MarshalBody decode their own output before sealing or
returning it; unusable extensions are reported.
- profile: period and genesis_time bounded to 2^53-1, genesis decoded as
unsigned.
- codec: Valid removed; empty values never encode as null.
- Regression tests for the nested-data seal/open asymmetry, the
nondeterministic verdict on NaN-keyed data and the quadratic disjointness
check; three new §64 mutations and five more.
- Fixtures: time_only_extensions regenerated with opaque data, new
time_and_key_portable_extension.dkk; genfixtures gains -only.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Reference implementation in Go, built from the implementation plan
(milestones M0 to M5): datekey, profile, provider, codec, agewrap,
extension, capsule, accesskey, the datekeys CLI, official vectors and
fixtures, the mutation corpus, fuzz targets, interop and live tests,
CI workflows, traceability and policy documents.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
dev