ethers.js/utils/address.js

116 lines
3.6 KiB
JavaScript

var BN = require('bn.js');
var convert = require('./convert');
var throwError = require('./throw-error');
var keccak256 = require('./keccak256');
function getChecksumAddress(address) {
if (typeof(address) !== 'string' || !address.match(/^0x[0-9A-Fa-f]{40}$/)) {
throwError('invalid address', {input: address});
}
address = address.toLowerCase();
var hashed = address.substring(2).split('');
for (var i = 0; i < hashed.length; i++) {
hashed[i] = hashed[i].charCodeAt(0);
}
hashed = convert.arrayify(keccak256(hashed));
address = address.substring(2).split('');
for (var i = 0; i < 40; i += 2) {
if ((hashed[i >> 1] >> 4) >= 8) {
address[i] = address[i].toUpperCase();
}
if ((hashed[i >> 1] & 0x0f) >= 8) {
address[i + 1] = address[i + 1].toUpperCase();
}
}
return '0x' + address.join('');
}
// See: https://en.wikipedia.org/wiki/International_Bank_Account_Number
var ibanChecksum = (function() {
// Create lookup table
var ibanLookup = {};
for (var i = 0; i < 10; i++) { ibanLookup[String(i)] = String(i); }
for (var i = 0; i < 26; i++) { ibanLookup[String.fromCharCode(65 + i)] = String(10 + i); }
// How many decimal digits can we process? (for 64-bit float, this is 15)
var safeDigits = Math.floor(Math.log10(Number.MAX_SAFE_INTEGER));
return function(address) {
address = address.toUpperCase();
address = address.substring(4) + address.substring(0, 2) + '00';
var expanded = address.split('');
for (var i = 0; i < expanded.length; i++) {
expanded[i] = ibanLookup[expanded[i]];
}
expanded = expanded.join('');
// Javascript can handle integers safely up to 15 (decimal) digits
while (expanded.length >= safeDigits){
var block = expanded.substring(0, safeDigits);
expanded = parseInt(block, 10) % 97 + expanded.substring(block.length);
}
var checksum = String(98 - (parseInt(expanded, 10) % 97));
while (checksum.length < 2) { checksum = '0' + checksum; }
return checksum;
};
})();
function getAddress(address, icapFormat) {
var result = null;
if (typeof(address) !== 'string') {
throwError('invalid address', {input: address});
}
if (address.match(/^(0x)?[0-9a-fA-F]{40}$/)) {
// Missing the 0x prefix
if (address.substring(0, 2) !== '0x') { address = '0x' + address; }
result = getChecksumAddress(address);
// It is a checksummed address with a bad checksum
if (address.match(/([A-F].*[a-f])|([a-f].*[A-F])/) && result !== address) {
throwError('invalid address checksum', { input: address, expected: result });
}
// Maybe ICAP? (we only support direct mode)
} else if (address.match(/^XE[0-9]{2}[0-9A-Za-z]{30,31}$/)) {
// It is an ICAP address with a bad checksum
if (address.substring(2, 4) !== ibanChecksum(address)) {
throwError('invalid address icap checksum', { input: address });
}
result = (new BN(address.substring(4), 36)).toString(16);
while (result.length < 40) { result = '0' + result; }
result = getChecksumAddress('0x' + result);
} else {
throwError('invalid address', { input: address });
}
if (icapFormat) {
var base36 = (new BN(result.substring(2), 16)).toString(36).toUpperCase();
while (base36.length < 30) { base36 = '0' + base36; }
return 'XE' + ibanChecksum('XE00' + base36) + base36;
}
return result;
}
module.exports = {
getAddress: getAddress,
}