fromHex validated only that the string was even-length, then used
parseInt(pair, 16) per byte. parseInt returns NaN for a non-hex pair, and a
Uint8Array stores NaN as 0 — so fromHex('zzzz') silently returned [0, 0]
instead of failing. Add a hex-charset check (allowing empty input) so bad
input throws. Add bytes.test.ts covering valid decode, round-trip, odd-length
and non-hex cases.
M1 of the ANS SDK (docs/ans-sdk.md):
- name: parse/format ans://v<semver>.<agent>.<domain>
- cbor: minimal RFC 8949 codec for the COSE_Sign1 subset
- verify/merkle: RFC 6962 leaf/node hashing, tree build, inclusion-proof
generation + verification
- verify/es256 + cose: COSE_Sign1 build/parse, Sig_structure, ES256 (WebCrypto)
- verify/rootkeys: kid -> verifier key (JWKS entries; sumdb-note is M2)
- verify: verifyReceipt() + verifyResolution() (signature + inclusion proof +
name binding), pure and offline
- client: AnsClient resolve/rootKeys/register/status over injectable fetch,
with a DnsApplier hook for verify-dns
Tests (24) cover name parsing, CBOR round-trips/vectors, RFC 6962 proofs, a full
ES256+Merkle receipt round-trip with positive/negative cases, and the client
against mocked fetch. Wired into the root build script.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>