@unstoppabledomains/resolution
Version:
Domain Resolution for blockchain domains
52 lines (51 loc) • 2.13 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.recover = exports.hashMessage = void 0;
var js_sha3_1 = require("js-sha3");
var index_1 = require("./index");
var elliptic_1 = require("elliptic");
var secp256k1 = new elliptic_1.ec('secp256k1');
var bytesLength = function (a) { return (a.length - 2) / 2; };
var bytesSlice = function (i, j, bs) {
return '0x' + bs.slice(i * 2 + 2, j * 2 + 2);
};
var bytesToNumber = function (hex) { return parseInt(hex.slice(2), 16); };
var decodeSignature = function (hex) { return [
bytesSlice(64, bytesLength(hex), hex),
bytesSlice(0, 32, hex),
bytesSlice(32, 64, hex),
]; };
var toChecksum = function (address) {
var addressHash = (0, js_sha3_1.keccak256)(address.slice(2));
var checksumAddress = '0x';
for (var i = 0; i < 40; i++) {
checksumAddress +=
parseInt(addressHash[i + 2], 16) > 7
? address[i + 2].toUpperCase()
: address[i + 2];
}
return checksumAddress;
};
var hashMessage = function (message) {
var messageBytes = (0, index_1.hexToBytes)(Buffer.from(message, 'utf8').toString('hex'));
var messageBuffer = Buffer.from(messageBytes);
var preamble = '\x19Ethereum Signed Message:\n' + messageBytes.length;
var preambleBuffer = Buffer.from(preamble);
var ethMessage = Buffer.concat([preambleBuffer, messageBuffer]);
return '0x' + (0, js_sha3_1.keccak256)(ethMessage.toString());
};
exports.hashMessage = hashMessage;
var recover = function (message, signature) {
var hash = (0, exports.hashMessage)(message);
var vals = decodeSignature(signature);
var vrs = {
v: bytesToNumber(vals[0]),
r: vals[1].slice(2),
s: vals[2].slice(2),
};
var ecPublicKey = secp256k1.recoverPubKey(Buffer.from(hash.slice(2), 'hex'), vrs, vrs.v < 2 ? vrs.v : 1 - (vrs.v % 2));
var publicKey = '0x' + ecPublicKey.encode('hex', false).slice(2);
var publicHash = '0x' + (0, js_sha3_1.keccak256)((0, index_1.hexToBytes)(publicKey));
return toChecksum('0x' + publicHash.slice(-40));
};
exports.recover = recover;