crypto.subtle only implemented digest. sign returned a fixed 32-byte
buffer, verify always returned true, encrypt and decrypt threw, and
generateKey, importKey and deriveBits handed back placeholder data.
Pages that use WebCrypto (anti-bot probes, PKCE and other auth flows,
client-side crypto) silently got wrong results.
Implement the secret-key half of WebCrypto on RustCrypto, following the
existing op_subtle_digest pattern:
- HMAC sign and verify (SHA-1/256/384/512)
- AES-GCM, AES-CBC and AES-CTR encrypt and decrypt
- PBKDF2 and HKDF deriveBits and deriveKey
- raw and symmetric JWK (oct) importKey and exportKey, generateKey,
wrapKey and unwrapKey
- getRandomValues and randomUUID now draw from the OS CSPRNG instead of
Math.random, so they are uniform across typed-array widths and no
longer a fingerprinting tell
Unsupported algorithms (RSA, ECDSA, ECDH) and key formats (pkcs8, spki)
throw NotSupportedError instead of returning fake data. The crypto runs
in stateless Rust ops; the bootstrap.js shim only marshals bytes and
normalizes algorithm parameters, so the native fast paths are untouched
and there is no cost unless a page calls crypto.
Verified against RFC 4231 (HMAC), the NIST GCM vectors, NIST SP800-38A
(AES-CTR), RFC 6070 (PBKDF2) and RFC 5869 (HKDF), plus roundtrip and
tag/padding tamper-rejection checks.
MrBeanDev
ed75730e2d