# Changelog All notable changes to this module are documented here. The project follows semantic versioning; `v0.x` versions make no API stability promise. ## Unreleased — specification v0.8.2 Moves the module to the DateKeys Protocol Specification v0.8.2, whose normative change closes the extension format (spec §76), refined, amended and corrected before release (see "Specification refinements", "Specification amendment: point canonicality" and "Specification corrections: formal review"). Framing and schema versions do not change. The CBOR library is replaced by a codec of the module's own, without reflection or dependencies. Every valid object encodes to the same bytes as before: the official vectors and fixtures are unchanged, and every error code and inspection step of the test suite and the mutation corpus is the same. ### Specification refinements v0.8.2 is unreleased, so these refinements amend it without a version change; spec §76 records each with its reproducible cases. No valid object changes, nor the verdict of any existing official vector or fixture; `dk1.json` gains four vectors for the reading rules of §19. - Layered error precedence (spec §69.1, with §57 and §63): within one object the code of the first failing layer is reported: frame, then type tag and schema version (keys 0 and 1), then the CBOR profile and the CDDL, then the fields with codes of their own in ascending key order; the rules with codes of their own belong to the last layer, not to the CDDL layer. Across objects and steps, the step order of §63 decides; step 9 now spells out its order (the `.dkk` as an object, then its binding to the capsule, then credentials, then the round time, then the request), and the errors of a `.dkk` come at step 9.a even when it is decoded earlier, and never under `time_only`. The optional inspection of steps 5, 6 and 8 and the `capsule_digest` check can change the code, and so could, until the corrections of the formal review, whether a network source verified the release. Steps 10, 11, 13 and 17 give the codes of the release verification (round, then signature) and of each identity. - Trust model (spec §55.1): who can write PUBLIC_HEADER, CONTROL_CBOR, PAYLOAD_AGE and the `.dkk` body, from which step each is bound and by what, and what none of them proves. Spec §72: an extension with security-relevant claims lives in CONTROL_CBOR or is signed by a signature extension; the data of `.dkk` extensions is advisory for its holder only. - One ordering rule for extension arrays (spec §31, §54, CDDL): strictly ascending unsigned bytewise order of the UTF-8 bytes of `extension_id`, a proper prefix first, never UTF-16 code units or a locale collation. - Rules that only `testdata/README.md` stated are now normative text: the age header grammar of C2SP and its codes (§28.1, §36), the round-time bound of 9999-12-31T23:59:59Z and pre-genesis instants (§15), the reading rules of `dk1_` (§19: either Base64 alphabet but no CR or LF, one JSON object in valid UTF-8 without a byte order mark, numbers by their exact decimal value), lengths of at least 1 (§22, §23, §40, §57), the comparison of the tlock stanza arguments (§35, §63 step 8), the Provider Profile rules and the chain-hash formula (§12.1, with `period` at most 2^32 − 1 and the name alphabets normative; the name lengths stay implementation limits), `extension_id` of at least one byte (§31), a repeated X25519 ephemeral share in INNER_ACCESS_AGE (§36), and the implementation limits of the reference (§74). These error codes of the reference change, for inputs that no existing official vector holds: - `capsule.Open` checks an offered `.dkk` as an object before binding it to the capsule: `access_type` and `access_material`, then its critical extensions, then `capsule_id`, then `capsule_digest`. A `.dkk` for another capsule with an unknown critical extension is now `ERR_EXTENSION_CRITICAL_UNKNOWN` (was `ERR_ACCESS_INVALID`), and one with an unsupported `access_type` and an unknown critical extension is `ERR_ACCESS_INVALID` (was `ERR_EXTENSION_CRITICAL_UNKNOWN`). - `accesskey.Decode` rejects a `BODY_LEN` of 0 with `ERR_INTEGRITY`, like a `PUBLIC_HEADER_LEN` of 0; it was `ERR_NON_CANONICAL_CBOR`, the empty body failing to decode. - `datekey.Parse` rejects CR and LF in a `dk1_` string with `ERR_DATEKEY_INVALID`; the Go Base64 decoders skipped them, and the result was `ERR_DATEKEY_NON_CANONICAL`. It also rejects invalid UTF-8 in the JSON at step 2 (see "Fixed"). - `datekeys decrypt -dkk` hands the `.dkk` to `capsule.Open` still encoded, through the new `OpenOptions.AccessKeyFile`, so its decoding errors come at step 9 of a `time_and_key` capsule, after any failure of steps 1 to 8, and a `time_only` capsule ignores it; the CLI used to fail on it before reading the capsule. - `capsule.Open` ignores nil entries of `OpenOptions.Identities`: with no other credential, the result is `ERR_ACCESS_REQUIRED` at step 9, before the clock is consulted, instead of `ERR_RELEASE_UNAVAILABLE` or a release request. - `agewrap.AccessIdentity` tries every identity on every stanza: an identity that unwraps two INNER_ACCESS_AGE stanzas is `ERR_POLICY_STRUCTURE_MISMATCH` even when another identity unwraps exactly one, whatever their order; the file used to open when the other came first. - `profile.NewRegistry` encodes and decodes each profile before comparing its `profile_hash`, so a profile gets the code `profile.Decode` reports: a `period` of 86401 s is `ERR_NON_CANONICAL_CBOR`, as in `Decode`, not `ERR_UNKNOWN_PROFILE`. `Profile.Validate` checks the schema rules a value can break (a period that is not a whole number of seconds in 1..86400, a genesis time outside 0..2^53−1, a name that is not valid UTF-8) first, with `ERR_NON_CANONICAL_CBOR`. Tests: `capsule.TestPrecedenceWithinPublicHeader`, `TestPrecedenceAcrossSteps`, `TestFrameLengthLowerBounds`, `TestMalformedAgeHeaders`, `TestTlockStanzaArgumentComparison`, `TestAccessKeyCheckOrder`, `TestAccessKeyFileAtStep9`, `TestControlCriticalBeforeHeaderBinding` and `TestTrustModel`; `accesskey.TestDecodePrecedence`; `agewrap.TestAccessIdentityStrictness`; `datekey.TestReadingRules`; `profile.TestDecodePrecedence` (a G1 point outside the prime-order subgroup), `TestPinPathMatchesDecode` and `TestChainHashFormula`; `provider.TestVerifyRejects`; `extension.TestOrderIsUnsignedBytewise`; `cmd/datekeys.TestDecryptAccessKeyOrder`. ### Specification amendment: point canonicality An amendment of the unreleased v0.8.2, recorded with its case in spec §76. The new §12.2 defines the canonical encoding of a BLS12-381 point, the compressed form of drand: the compression flag set, the infinity flag only for the point at infinity with every other bit zero, the sort flag for the lexicographically largest y, big-endian coordinates below p (c1 then c0 in G2) and a point of the prime-order subgroup. A decoder rejects every other string, among them x + p and an identity with a payload. The Provider Profile public key (§12.1), the release signature (§63 step 10) and the U of the tlock stanza (§63 step 11) are canonical and never the point at infinity, and step 11 defines the stanza body, `U || V || W` with |V| = |W| = 16 (128 bytes for Quicknet), and the IBE check r·G == U. The case, from the second implementation: `tlock-js` on `@noble/curves` 1.9.7 accepted U re-encoded as c0 + p and a signature re-encoded as x + p and returned the same file key, where the reference rejects both. No error code or step of the reference changes: its decoder, `kilic/bls12-381` through drand, already rejected those encodings. A U at infinity, which only the IBE check used to reject, is refused before decryption, with the same `ERR_INTEGRITY`. Spec §64 gains ten mutations, exported in `mutations.json`: U with c0 + p, U at infinity, U with the infinity flag and a payload, and tlock stanza bodies of 127 and 129 bytes, each with a valid header MAC (`ERR_INTEGRITY`, step 11); a release signature with x + p, at infinity, with the infinity flag and a payload, negated, and negated together with U with c0 + p (`ERR_RELEASE_INVALID`, step 10). The x + p case is a capsule for round 1004, whose published signature `testkit` now knows (`testkit.XPlusPRound`): no fixture round has an x below 2^381 − p. No fixture and no other vector changes. Tests: `profile.TestDrandPointDecodersAreCanonical`, which fails if a dependency update makes the decoders of drand lenient, and `TestPublicKeyEncodingIsCanonical`; new cases in `provider.TestVerifyRejects`, `agewrap.TestTimeIdentityStrictness` and `TestTimeIdentityRelease`; `capsule.TestPointMutationsChangeOnlyTheEncoding`, which checks that each point mutation differs from a capsule that opens only in one encoding; `internal/testkit.TestPointReencodings`. ### Specification corrections: formal review Corrections of the unreleased v0.8.2 from the formal review of the specification, recorded with their cases in spec §76 ("Correcciones de la revisión formal"). Three change normative rules: - A source that fetches releases over a network (a relay, the Release API or a cache) must verify every response with the rules of step 10 and discard the one that fails; when none passes, the code is `ERR_RELEASE_UNAVAILABLE` at step 9 (spec §63). The codes of step 10 are those of a release supplied directly, as in the official vectors. `provider/drand.Client` already did this; the contract of `provider.ReleaseSource` and the documentation of `capsule.OpenOptions.Source` now say so. - Each registered extension declares the objects (PUBLIC_HEADER, CONTROL_CBOR, `.dkk`) and the arrays where it may appear, and a known extension elsewhere is treated as unknown there (spec §31, §54, §72): a critical one is `ERR_EXTENSION_CRITICAL_UNKNOWN`, a noncritical one is ignored. The new optional interface `extension.Placement` of a `Registry` tells where each extension is registered; `capsule.Inspect` and `capsule.Open` check the arrays of PUBLIC_HEADER (step 4), of the `.dkk` (step 9.a) and of CONTROL_CBOR (step 14) with the new `extension.CheckCriticalIn` and `extension.CheckNoncriticalIn`. A `Registry` that does not implement it behaves as before. - H2, H3 and H4 of step 11 are those of drand/kyber `encrypt/ibe`, and H2 hashes the element of GT in the order of `kilic/bls12-381`: c1 before c0 at every level of the tower, each coordinate of Fp in 48 bytes big-endian. The new vector file `testdata/vectors/tlock_ibe.json` freezes H2(e(G1, G2)) = `cb87319f24560b5231579a09ad79f12e`; the order of `Fp12.toBytes` of noble, c0 first, gives `0118eea9d5971745f71e3c94926f1717` and another file key. The other findings are editorial: §27 defers the authenticity of PUBLIC_HEADER to the trust model (§55.1) and says that the age header MAC protects only against whoever does not know the file key; step 5 separates the mandatory read of SEALED_CONTROL from the optional inspection of its age header; step 15 names `ERR_HEADER_BINDING`; §21 makes the 16 CSPRNG bytes of `capsule_id` a MUST; §77 gains drand/kyber, RFC 8259, RFC 8610 and RFC 4648; §76 retitles its section "Cambios normativos de la v0.8.2" and corrects its record: `dk1.json` gained four vectors, not three, and two cases of the refinements quoted texts that no earlier version contained. No error code of the reference changes, nor any fixture or existing vector. `github.com/drand/kyber-bls12381`, already an indirect dependency through drand and tlock, becomes a direct requirement: `internal/testkit` and a test compute the pairing with it. Tests: `capsule.TestReleaseFromANetworkSource` (a relay whose only answer is a release of another round, or a negated signature, gives `ERR_RELEASE_UNAVAILABLE` at step 9 through `provider/drand.Client`, and the same release supplied directly the code of step 10); `capsule.TestExtensionPlacement` (an extension registered for CONTROL_CBOR only is unknown in PUBLIC_HEADER and in a `.dkk`, one registered as noncritical only is unknown in a critical array, and a noncritical copy outside its registration is ignored); `extension.TestPlacement`; `agewrap.TestTlockH2Vector` (the frozen vector, and step 11 recomputed with H2 and H4 against the file key that tlock unwraps). A second round of the same review confirmed these corrections and asked for three more, recorded in spec §76 as corrections 4 to 6: - An encoder must not write a registered extension in an object or array it is not registered for, and a reader that ignores a noncritical one for that reason must not interpret its data (spec §54, §72). A writer could seal in the critical extensions of CONTROL_CBOR one registered there as noncritical only, which a reader that knows the registration rejects at step 14, after the unlock. `capsule.Encrypt` and `accesskey.Encode` take no `Registry`: they write the extensions they are given, and the application, which knows the registration, applies the rule. - §17 and §51 give the codes of step 10 only for a release supplied directly, as step 10 does; one that a network source fetches and that breaks those rules is discarded at step 9. - Whatever the failure of the release source, step 9 reports `ERR_RELEASE_UNAVAILABLE` and no other code (spec §63). The other findings are editorial: §28.1 says that steps 5 and 6 parse only the age header, since step 5 reads all of SEALED_CONTROL; step 9 has a single arrow to `ERR_RELEASE_UNAVAILABLE`; §76 rewords two introductions. `testdata/README.md` says where the extensions of the mutation corpus are registered: in both arrays of every object. These error results of the reference change, for inputs that no official vector holds: - `capsule.Open` reports any error of `OpenOptions.Source` at step 9 with `ERR_RELEASE_UNAVAILABLE` as its only code. An error that carries another normative code, or none, keeps only its text: a caller's source that failed with `ERR_RELEASE_INVALID` gave `ERR_RELEASE_INVALID` at step 9. An error that wraps `ERR_RELEASE_UNAVAILABLE` alone is returned as it is, with its other causes, such as a context error. - The error of `provider/drand.Client.Fetch` wraps `ERR_RELEASE_UNAVAILABLE` and no other normative error, as `errors.go` promises for every error of the module. The failure of each relay is kept in its text only, where `errors.Join` wrapped it: a relay that answered with a release of another round also made the error match `ERR_ROUND_MISMATCH`. A context that ended is still wrapped, whether `Fetch` sees it end before or after the relays fail because of it. Tests: `capsule.TestReleaseSourceErrorsAtStep9` (a source error with another code, two codes or none gives `ERR_RELEASE_UNAVAILABLE` alone at step 9 and keeps its text); `capsule.TestExtensionPlacement`, which now also covers the noncritical array of a `.dkk`, so that checking it with the object-blind `extension.CheckNoncritical` fails; `provider/drand.TestFetchErrorHasOneCode` and `TestUnavailabilityAndCancellation` (a canceled context and a deadline during the request); `datekeys.TestCode`. ### Breaking changes - `extension.New(id, version, data []byte)` takes the opaque data bytes instead of a value that it encoded as CBOR, and rejects nil or empty data. An extension without data is the literal `extension.Extension{ID, Version}`, which omits key 2. - Extension data (key 2) must be a byte string of at least one byte. Any other CBOR type, `null` or `h''` at key 2 is now `ERR_NON_CANONICAL_CBOR`, so a v0.8.1 object with such data no longer decodes. The base protocol never decodes the content (§54). - `codec.Valid` and its fuzz target `codec.FuzzValid` are removed: nothing decodes extension data any more. - Package `codec` is rewritten without reflection, struct tags or dependencies (§58). Removed: `Marshal`, the reflection-based `Unmarshal(data, v)` and `Peek(data, v)`, and `MaxNestedLevels`, `MaxArrayElements` and `MaxMapPairs`. Each schema now writes its encoding with a `codec.Encoder` (`Map`, `Array`, `Uint`, `Bstr`, `Text`, `Out`, with a sticky first error, and `Fail`, which records an error of the schema so that `Out` never returns bytes its decoder rejects) and reads it with a strict `codec.Decoder` (`NewDecoder`, `Map`, `Key`, `EndMap`, `Array`, `Uint`, `Bstr`, `Text`, `Done`). `codec.Unmarshal(in, decode, encode)` runs the decoder of a schema and requires that its re-encoding reproduces the input; `codec.Peek(in)` returns the type tag, of at most `codec.MaxTypeTagLen` (64) bytes, and the schema version; `codec.Walk(in, maxDepth, maxLen)` checks that bytes are one item of the §58 profile, for vectors, fuzzing and diagnostics. `CheckSchema` and `MaxSafeUint` keep their names. - `extension.Wire` and its `UnmarshalCBOR` are removed. `extension.Encode` becomes `extension.Canonical`, which returns the validated array in canonical order as `[]Extension`; `extension.Decode([]Wire)` becomes `extension.DecodeArray(*codec.Decoder)`, which reads and validates one array and rejects more than 64 entries from the array head, before reading any; `extension.EncodeArray(*codec.Encoder, []Extension)` writes one, and records in the Encoder, instead of writing it, an array that `DecodeArray` would reject. - `codec.CheckSchema` reads keys 0 and 1 only, and nothing after them (§70): the map head, key 0, a type tag of at most 64 bytes, key 1 and the version must be in the profile, each head in its shortest form, and the version at most 2^53−1. A schema version other than the expected one read that way is `ERR_UNSUPPORTED_VERSION` whatever follows it; it was `ERR_NON_CANONICAL_CBOR` when the rest of the object was malformed. Every other form of the version is now `ERR_NON_CANONICAL_CBOR`, where it was `ERR_UNSUPPORTED_VERSION` whenever the value read was not the expected one: a missing version, `null` or `undefined`, a version not in its shortest form, a version above 2^53−1 (up to 2^64−1), a version that is not the second key (placed before key 0 or after another key), and a version behind a map head or a type tag head not in its shortest form. `true` and `false` were already `ERR_NON_CANONICAL_CBOR`. - `capsule.DecodeHeader` checks every CDDL rule of PUBLIC_HEADER, including `access_policy`, the extension arrays and the cross-array rule, before it parses the DateKey (§57, §63 step 4). A header that breaks both reports `ERR_NON_CANONICAL_CBOR` where it reported `ERR_DATEKEY_INVALID` or `ERR_DATEKEY_NON_CANONICAL`; a header with one fault keeps its code. - `profile.Profile.CanonicalCBOR` and `Hash` refuse a `profile_id`, `provider`, `network` or `scheme` that is not valid UTF-8, with `ERR_NON_CANONICAL_CBOR`: they wrote it as an invalid text string. Every encoder refuses such text. - At most 64 extensions per array and `extension_version` at most 2^32−1, on encode and decode (`ERR_NON_CANONICAL_CBOR`). An `extension_id` appears at most once per object, and arrays are ordered by `extension_id` only. - Provider Profile: `genesis_time` is an unsigned integer, and `period` and `genesis_time` are at most 2^53−1; a negative or larger value is `ERR_NON_CANONICAL_CBOR`. - `null` in a byte-string field is `ERR_NON_CANONICAL_CBOR` (for example a `null` `access_material` was `ERR_ACCESS_INVALID`): nil byte strings, arrays and maps now encode as empty ones, never as `null`. - `capsule.EncodeHeader` and `capsule.DecodeHeader` enforce the 1 MiB PUBLIC_HEADER limit and `accesskey.DecodeBody` the 16 MiB BODY limit. Every frame-limit refusal, including those of `accesskey.MarshalBody` and of `capsule.Encrypt` for SEALED_CONTROL, now wraps `ERR_INTEGRITY` (§57). - `profile.Profile.CanonicalCBOR` refuses a `period` or `genesis_time` outside the schema with `ERR_NON_CANONICAL_CBOR`, as `profile.Decode` does. - The official fixture `time_only_extensions` is regenerated: its header data is the raw UTF-8 bytes of "public label" and its control data is `{0: 7, 1: "sealed"}` (`a2000701667365616c6564`). Every other `.dkc` and `.dkk` keeps its bytes; the fixture and vector metadata name spec 0.8.2. ### Added - `capsule.OpenOptions.AccessKeyFile`, a `.dkk` still encoded, which `Open` decodes at step 9.a and only for a `time_and_key` capsule (§63, §69.1). - `ErrExtensionDataInvalid` (`ERR_EXTENSION_DATA_INVALID`, §69). - `extension.Placement`, an optional interface of a `Registry` that tells in which objects and arrays each extension is registered, with `extension.Object` (`PublicHeader`, `Control`, `AccessKey`), `extension.Array` (`Critical`, `Noncritical`), `extension.KnownIn`, `extension.CheckCriticalIn` and `extension.CheckNoncriticalIn` (§54, §72). `CheckCritical` and `CheckNoncritical`, which do not know the object, keep their behaviour and consult no `Placement`. - `testdata/vectors/tlock_ibe.json`, the H2 vector of §63 step 11, generated by `internal/testkit.IBEVectors` and documented in `testdata/README.md`. - `extension.DataValidator`, an optional interface of a `Registry` that validates the data of the extensions it knows: a known critical extension with invalid data fails with `ErrExtensionDataInvalid` (§63 steps 4 and 14, and the `.dkk` check); a known noncritical one is reported in `capsule.Inspection.UnusableExtensions`, `capsule.Opened.UnusableControlExtensions` or `capsule.Opened.UnusableAccessKeyExtensions` (`extension.CheckNoncritical`, `extension.Unusable`) and does not fail. - Encoder self-checks: `capsule.Encrypt` decodes its PUBLIC_HEADER and CONTROL_CBOR, and `accesskey.MarshalBody` its body, with the readers' decoders before sealing or writing (§72). - `extension.MaxExtensions`, `MaxVersion`, `MaxDataLen`, `codec.MaxSafeUint` and `codec.MaxTypeTagLen`. - The `.dkk` fixture `time_and_key_portable_extension`, which carries a noncritical extension with data (§68). - `genfixtures -only NAME[,NAME...]` regenerates the named fixtures only. - Tests: the three new §64 mutations (data that is not a byte string, `h''` data, 65 extensions), regression tests for the cases of §76, conformance checks on the exact data bytes, and the fuzz target `capsule.FuzzEncodeImpliesDecode` (header, control and `.dkk`). - The mutation corpus moves from `capsule/mutation_test.go` to `internal/testkit.Mutations`, shared by the test and by `genfixtures`. Its third-party X25519 identity is now fixed (`testkit.Stranger`), and every release source answers with one recorded release, as the exported corpus describes it. The CLI's inspect view moves to `internal/inspectview`, which `genfixtures` uses to freeze the outputs. - `internal/cbortest`, an encoder and decoder of generic CBOR values written independently of `codec`: tests build with it inputs outside the profile and check `codec` against it. - Tests of the map structure of every schema (key order, required and unknown keys, entry counts) and of the codec, whose statement coverage is 100 %. - `access_policy` values whose low byte is 0 or 1 (256, 257, 65536, 2^32, 2^53−256…) are tested as undefined, as `FuzzDecodeHeader` seeds and as two mutations with a consistent `header_binding` (`testkit.Build.RawPolicy`). - Tests `extension.TestEncodeArrayRejects`, `accesskey.TestEncodeAndDecodeLeaveNoStaleMaterial`, `accesskey.TestDecodeShortBodyAllocatesLittle` and `capsule.TestDecryptAll`. - Shared test data for a second implementation, generated by `genfixtures`, regenerated by the gate and documented in `testdata/README.md`: - `testdata/vectors/cbor.json`: 36 accepted and 67 rejected items of the §58 profile, walked with `codec.Walk` (integers above 2^53−1 as decimal strings), and 135 schema vectors: minimal valid object, unknown key, missing key, wrong type, size and range for the Provider Profile, PUBLIC_HEADER, CONTROL_CBOR, the `.dkk` body, `verification_metadata` and extensions (data `40` and `5801xx`, data of every other type, 64 and 65 extensions, a leading BOM, the U+FF61/U+10000 order, `extension_version` 2^32−1 and 2^32); schema versions 2^53 and 2^64−1 and the order of type tag and version; and the Provider Profile validation (names, public key, `genesis_time`, drand scheme, the chain-hash self-check with its formula, the `period` limit), each vector keeping the chain hash consistent unless it tests the self-check. - `testdata/vectors/mutations.json`: the mutation corpus as frozen data, 65 cases (the 33 of §64 first), each a `.dkc` given as edits of a fixture and what the reader is given (`.dkk`, identities, the recorded release, clock, registry, known extensions), with the expected error and step. The 17 capsules built with age randomness are kept from the committed file; `genfixtures -only mutations` rebuilds them. - `testdata/vectors/inspect_differential.json`: 1825 deterministic mutations of the five `.dkc` fixtures (bit flips, byte changes, truncations, insertions, deletions, length fields, CBOR-aware header edits, DateKey edits, age header edits) with the verdict of steps 1 to 8. - `testdata/fixtures/.inspect.json`: the exact output of `datekeys inspect -json -in .dkc` for each official capsule. - `testdata/README.md` points to the sections of the specification that decide each verdict (§12.1, §15, §19, §22, §23, §28.1, §63, §69.1, §74), which the refinements above moved into normative text. - `spec/datekeys.cddl` marks the one-day `period` limit of the Provider Profile, which `profile.Decode` already applied, as an implementation limit of the reference (§57, §74); spec §11 allows up to 2^53−1. - Tests that replay them: `codec.TestSharedVectors`, `internal/testkit.TestSchemaVectors`, `capsule.TestExportedMutationCorpus`, `capsule.TestInspectDifferentialCorpus` and `cmd/datekeys.TestInspectJSONGoldens`. - Fuzz targets `codec.FuzzDecoder` (the Decoder primitives), `codec.FuzzWalk` (against the independent decoder), `codec.FuzzPeek`, `codec.FuzzEncodeImpliesWalk` and `extension.FuzzDecodeArray`, run by `scripts/fuzz.sh`; `codec.FuzzUnmarshal` now fuzzes a hand-written schema. ### Removed - The dependencies `github.com/fxamacker/cbor/v2` and `github.com/x448/float16`. `go.mod` requires nothing new. ### Fixed - Error messages no longer copy the text of an error of age, tlock, kyber, drand or kyber-bls12381. When the IBE check of a tlock stanza failed, kyber's error carried the candidate plaintext and r, and `agewrap.TimeIdentity` copied it into its error, and so into the error of `capsule.Open` and the details of `Inspection.Checks`: a third party who edited W learned FK_TIME from the message. Each such failure now has a fixed message with its normative error and a reason of its own: the length of the tlock stanza body, the encoding of U, U at infinity or the IBE check; the header or the STREAM of an age file; a malformed X25519 stanza. A failure of the writer of the plaintext at step 17 keeps its own text. `capsule.TestTlockFailureDiagnosticsCarryNoSecrets`, `TestPlaintextWriterFailureKeepsItsText`. - `datekey.Parse` rejects invalid UTF-8 in the `dk1_` JSON at step 2, as §19 requires. `encoding/json` replaced it with U+FFFD, so a member that a repeated name overwrites passed steps 2 and 3 and ended as `ERR_DATEKEY_NON_CANONICAL` instead of `ERR_DATEKEY_INVALID`. Found by the second implementation's differential; new `dk1.json` vector. - `extension.CheckDisjoint` is a linear merge of the two sorted arrays; a PUBLIC_HEADER with 40 000 + 40 000 extensions took 8.3 s in the pairwise check (§76, case 6). - Control data made of 14 or 15 nested arrays was sealed by `Encrypt` and rejected by `Open` at step 14, after the unlock (§76, case 5). - Header data `{NaN: 0, NaN: 1}` gave a nondeterministic verdict (§76, case 3). - `extension.New(id, v, nil)` wrote `null` as data (§76, case 2). - `codec.Unmarshal` wipes its re-encoding, which after the new self-checks held a copy of I_PAYLOAD or `access_material`, and `accesskey.DecodeBody` wipes the material on its error paths. The `codec.Encoder` also wipes every buffer it outgrows, and `codec.Unmarshal` sizes its re-encoding for the input; the former library's internal buffers could keep a copy. - `accesskey.Encode` wipes the body it wrote, and `accesskey.Decode` reads the body into a buffer that grows with the data read, wiping every buffer it outgrows, and wipes the body once decoded or on error: both left copies of `access_material` behind. The in-memory age decryption of SEALED_CONTROL and INNER_ACCESS_AGE in `capsule.Open` reads the plaintext into one buffer of the ciphertext's size instead of a growing one, so that no outgrown buffer keeps a copy of I_PAYLOAD. Buffers internal to `filippo.io/age` and copies made by the Go runtime stay out of reach (SECURITY.md). ## Unreleased — v0.1.0 First implementation of the DateKeys Protocol Specification v0.8.1. ### Added - `datekey`: local date → round resolution at full precision (§15), canonical `dk1_` encoding and strict parsing (§18, §19). - `profile`: Provider Profile Deterministic CBOR and `profile_hash` (§11), the pinned Quicknet profile with its chain-hash self-check (§12), and pinned registries (§13). - `provider`: release sources and local BLS verification (§51); `provider/drand`: racing public relays, verifying every answer (§48, §49, §52). - `codec`: Deterministic CBOR with a re-encoding canonicality check (§58, §58.1). - `extension`: the generic extension mechanism (§54). - `agewrap`: strict tlock and X25519 age identities that enforce the stanza rules (§27, §29, §32, §33, §35), and a secret-free header probe. - `capsule`: `.dkc` framing, `Encrypt` for `time_only` and `time_and_key` (§61, §62), `Inspect` (§63 steps 1–8) and `Open` (§63 steps 9–18). - `accesskey`: `.dkk` encoding and decoding (§40–§44). - `cmd/datekeys`: `encrypt`, `decrypt`, `inspect`, `datekey resolve`, `profile hash`, with atomic, non-overwriting outputs. - Official vectors (§65, §66), `.dkc`/`.dkk` fixtures (§67, §68), the mutation corpus (§64), fuzz targets for every parser, interoperability tests with the official `age` and `tle` CLIs, and live Quicknet integration tests. - `spec/datekeys.cddl` and `docs/traceability.md`.