coin 0.2.0

Cross-platform multi-coin cryptocurrency toolkit: Monero, Bitcoin, EVM. BIP-32/39/44 HD keys, Schnorr/ECDSA signing, PSBT, BIP-47, MuSig2, ABI codec, native secp256k1 FFI with pure-Dart fallback.

Changelog

0.2.0

Fixed: taproot output keys and addresses were wrong for odd-Y internal keys

Taproot.tweakedKey tweaked the internal key as derived instead of its BIP-341 lift_x (even-Y) form. Roughly half of all internal keys have an odd Y, and for every one of those the computed output key, and therefore the P2TR address, was wrong. Taproot.tweakSecretKey had the mirror defect, so a key-path spend signed with the wrong tweaked key.

Who is affected: anyone using 0.1.0 to derive, display or store P2TR addresses, or to sign key-path spends. Funds sent to an affected address are not spendable by the key the caller believes owns them; they are recoverable only with the correct internal key and external tooling.

What to do: upgrade, then re-derive any P2TR address produced by 0.1.0 and compare. Addresses that change were wrong. Treat any 0.1.0-derived P2TR address already given out as suspect until re-derived.

The fix normalises the internal key to its even-Y form before tweaking, in tweakedKey, in tweakSecretKey (by negating the secret key when the public Y is odd) and in the control-block parity bit. Regression coverage uses the BIP-86 address vectors, including an odd-Y case, and the BIP-341 key-path vectors. 0.1.0 shipped this defect because the suite had no assertion on a taproot tweak at all.

Also in this release

• Crypto primitives: X25519 (RFC 7748), ChaCha20-Poly1305 (RFC 8439), Ed25519 (RFC 8032), AES-256-CBC, HKDF (RFC 5869), SHA-256/512, HMAC (RFC 4231), RIPEMD-160; NIST P-256 ES256 verify + JWK decode.
• BIP-327 MuSig2 noncecoef fix; off-curve public-key rejection. secp256k1 ECDSA, Schnorr (BIP-340), BIP-32/39, Base58Check, bech32/bech32m, RLP.
• Firo/Dash special transactions (DIP-2 / ExTx); MWEB (Litecoin) parse/txid
  • ltcmweb address parsing; taproot BIP-341 key-path fix; PSBT BIP-174; TxAssembler BIP-143 witness + BIP-69 ordering.
• EVM: EIP-1014 CREATE2; EIP-55/155/2930/1559/191/712/137, RLP, ABI, ERC-4337 userOpHash, EIP-7702, ERC-1271.
• WalletConnect transport crypto only (no Sign/Auth engine): v2 envelopes, SHA-256 topic, EdDSA relay-auth JWT, wc: URI, v1 AES-CBC+HMAC cipher; Verify API attestation via the in-house P-256.
• HD account address derivation (BIP-44/49/84/86).

0.1.0

• Initial release.
• Bitcoin: P2PKH, P2SH, P2WPKH, P2WSH, P2TR address types and signing.
• BIP-32 HD key derivation (DerivedKey, DerivedSecretKey, DerivedPublicKey).
• BIP-39 mnemonic generation and BIP-39 seed derivation (PBKDF2-HMAC-SHA512).
• BIP-340 Schnorr signing and verification (SchnorrSig).
• BIP-143 witness sighash (WitnessSigHasher) and legacy sighash (LegacySigHasher).
• BIP-174 PSBT builder.
• BIP-47 payment codes and shared address derivation.
• BIP-327 MuSig2 key aggregation and partial signing.
• UTXO chain support: BCH (SIGHASH_FORKID), Litecoin, Dogecoin.
• Ethereum / EVM: EIP-55 addresses, EIP-1559 and legacy transactions, ABI codec.
• Monero: Ed25519 keys, primary and subaddresses, ring signature primitives.
• secp256k1 via native FFI (libsecp256k1) on native targets; pure-Dart fallback for web.
• Ed25519 via native FFI on native targets; pure-Dart fallback.
• Bech32 and Bech32m encode/decode (BIP-173, BIP-350).
• Base58Check encode/decode.
• Hash functions: SHA-256, SHA-512, RIPEMD-160, HMAC-SHA-256/512, PBKDF2.