bip322-js
Version:
A Javascript library that provides utility functions related to the BIP-322 signature scheme
87 lines • 3.66 kB
JavaScript
;
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
var desc = Object.getOwnPropertyDescriptor(m, k);
if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
desc = { enumerable: true, get: function() { return m[k]; } };
}
Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
o["default"] = v;
});
var __importStar = (this && this.__importStar) || function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
__setModuleDefault(result, mod);
return result;
};
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
// Import dependencies
const secp256k1_1 = __importDefault(require("secp256k1"));
const BufferUtil_1 = __importDefault(require("./BufferUtil"));
const bitcoinMessage = __importStar(require("bitcoinjs-message"));
/**
* Class that implement BIP137-related utility functions.
*/
class BIP137 {
/**
* Check if a given signature satisified the format of a BIP-137 signature.
* @param signature Base64-encoded signature to be checked
* @returns True if the provided signature correspond to a valid BIP-137 signature, false if otherwise
*/
static isBIP137Signature(signature) {
// Check if the provided signature satisified the format of a BIP-137 signature
const signatureBuffer = Buffer.from(signature, 'base64');
if (signatureBuffer.byteLength === 65) {
return true;
}
else {
return false;
}
}
/**
* Derive the public key that signed a valid BIP-137 signature.
* @param message Message signed by the signature
* @param signature Base-64 encoded signature to be decoded
* @returns Public key that signs the provided signature
*/
static derivePubKey(message, signature) {
// Compute the hash signed by the signer
const messageHash = bitcoinMessage.magicHash(message);
// Decode the provided BIP-137 signature
const signatureDecoded = this.decodeSignature(Buffer.from(signature, 'base64'));
// Recover the public key
return Buffer.from(secp256k1_1.default.ecdsaRecover(signatureDecoded.signature, signatureDecoded.recovery, messageHash, signatureDecoded.compressed));
}
/**
* Decode a BIP-137 signature.
* Function copied from bitcoinjs-message library.
* @param signature BIP-137 signature to be decoded
* @returns Decoded BIP-137 signature
*/
static decodeSignature(signature) {
if (signature.length !== 65)
throw new Error('Invalid signature length');
const flagByte = signature.readUInt8(0) - 27;
if (flagByte > 19 || flagByte < 0) {
throw new Error('Invalid signature parameter');
}
return {
compressed: !!(flagByte & 12),
recovery: flagByte & 3,
signature: BufferUtil_1.default.ensureBuffer(signature.subarray(1))
};
}
}
exports.default = BIP137;
//# sourceMappingURL=BIP137.js.map