multichain-address-validator
Version:
Multichain address validator for Bitcoin and other blockchains.
50 lines (49 loc) • 2.44 kB
JavaScript
import cryptoUtils from '../crypto/utils.js';
import { getAddress } from '../helpers.js';
// from https://github.com/paritytech/substrate/wiki/External-Address-Format-(SS58)
const addressFormats = [
{ addressLength: 3, accountIndexLength: 1, checkSumLength: 1 },
{ addressLength: 4, accountIndexLength: 2, checkSumLength: 1 },
{ addressLength: 5, accountIndexLength: 2, checkSumLength: 2 },
{ addressLength: 6, accountIndexLength: 4, checkSumLength: 1 },
{ addressLength: 7, accountIndexLength: 4, checkSumLength: 2 },
{ addressLength: 8, accountIndexLength: 4, checkSumLength: 3 },
{ addressLength: 9, accountIndexLength: 4, checkSumLength: 4 },
{ addressLength: 10, accountIndexLength: 8, checkSumLength: 1 },
{ addressLength: 11, accountIndexLength: 8, checkSumLength: 2 },
{ addressLength: 12, accountIndexLength: 8, checkSumLength: 3 },
{ addressLength: 13, accountIndexLength: 8, checkSumLength: 4 },
{ addressLength: 14, accountIndexLength: 8, checkSumLength: 5 },
{ addressLength: 15, accountIndexLength: 8, checkSumLength: 6 },
{ addressLength: 16, accountIndexLength: 8, checkSumLength: 7 },
{ addressLength: 17, accountIndexLength: 8, checkSumLength: 8 },
{ addressLength: 34, accountIndexLength: 32, checkSumLength: 2 },
];
function verifyChecksum(address) {
try {
const preImage = '53533538505245';
const decoded = cryptoUtils.base58(address);
const addressType = cryptoUtils.byteArray2hexStr(decoded.slice(0, 1));
const addressAndChecksum = decoded.slice(1);
// get the address format
const addressFormat = addressFormats.find(af => af.addressLength === addressAndChecksum.length);
if (!addressFormat) {
throw new Error('Invalid address length');
}
const decodedAddress = cryptoUtils.byteArray2hexStr(addressAndChecksum.slice(0, addressFormat.accountIndexLength));
const checksum = cryptoUtils.byteArray2hexStr(addressAndChecksum.slice(-addressFormat.checkSumLength));
const calculatedHash = cryptoUtils
.blake2b(preImage + addressType + decodedAddress, 64)
.substr(0, addressFormat.checkSumLength * 2)
.toUpperCase();
return calculatedHash == checksum;
}
catch (err) {
return false;
}
}
export default {
isValidAddress(address) {
return verifyChecksum(getAddress(address));
},
};