@stars-labs/yubiwallet-wasm

WASM bindings for YubiWallet's chain-independent logic — address derivation and EVM signature recovery — for wallet integrators (browser extensions and web apps).

⚠️ This package cannot sign. A browser/WASM context cannot reach the YubiKey's PIV/OpenPGP (CCID) interface. Signing must go through the native messaging host (yubiwallet-host). What you get here are the pure pieces that don't need the card: turning a public key into an address, and turning the card's raw R‖S output into an EIP-155 (r, s, v) signature.

Install

npm install @stars-labs/yubiwallet-wasm

Usage

The package ships a web target (ES module + init()). Initialize the wasm module once, then call the functions.

import init, {
  solana_address,
  eth_address,
  eth_signature,
} from "@stars-labs/yubiwallet-wasm";

await init(); // load the .wasm (once)

// Solana address (base58) from a 32-byte Ed25519 public key (hex)
const sol = solana_address("e3b0c44298fc1c149afbf4c8996fb924...");

// Ethereum address (0x…) from a 65-byte uncompressed secp256k1 key (hex)
const addr = eth_address("04a1b2c3...");

// Recover an EIP-155 signature from the card's raw R‖S (64-byte hex)
const sig = eth_signature(
  pubkeyHex, // 65-byte uncompressed signer key (hex)
  hashHex,   // 32-byte message hash the card signed (hex)
  rsHex,     // 64-byte R‖S from the card (hex)
  1n,        // chain id (bigint)
);
console.log(sig.r, sig.s, sig.v);

All hex arguments accept an optional 0x prefix.

API

| Function | Returns | Description | | --- | --- | --- | | solana_address(pubkey_hex) | string | Base58 Solana address from a 32-byte Ed25519 key. | | eth_address(pubkey_hex) | string | 0x… Ethereum address from a 65-byte uncompressed secp256k1 key. | | eth_signature(pubkey_hex, hash_hex, rs_hex, chain_id) | EvmSignature | EIP-155 (r, s, v) recovered from the card's raw R‖S. |

EvmSignature exposes .r (hex string), .s (hex string), and .v (bigint).

Where signing happens

 browser extension / web app
        │  address derivation, (r,s,v) recovery
        ▼
 @stars-labs/yubiwallet-wasm        ← this package (no card access)
        │  sign request (raw hash)
        ▼
 yubiwallet-host  ──APDU──▶  YubiKey (PIV / OpenPGP)

See the main repository and docs/dapp-bridge-design.md for the native-host bridge that performs the actual signing.

License

MIT OR Apache-2.0