browser-authenticator.js/authenticator.js

100 lines
2.9 KiB
JavaScript

(function (exports) {
'use strict';
var Authenticator = exports.Authenticator || exports;
var Unibabel = window.Unibabel; // || require('unibabel');
var totp = window.totp; // || require('notp').totp;
if (!window.crypto) {
document.addEventListener('mousemove', function (event) {
var ev = event || window.event;
window.forge.random.collectInt(ev.pageX, 16);
window.forge.random.collectInt(ev.pageY, 16);
});
}
// Generate a key
function generateOtpKey() {
// 20 cryptographically random binary bytes (160-bit key)
try {
var key = window.crypto.getRandomValues(new Uint8Array(20));
return Promise.resolve(key);
} catch(e) {
// Promises are supported even in Microsoft Edge
// only old IE and old android need shims
return new Promise(function (resolve, reject) {
window.forge.random.getBytes(20, function (err, bytes) {
if (err) {
reject(err);
return;
}
resolve(Unibabel.binaryStringToBuffer(bytes));
});
});
}
}
// Text-encode the key as base32 (in the style of Google Authenticator - same as Facebook, Microsoft, etc)
function encodeGoogleAuthKey(bin) {
// 32 ascii characters without trailing '='s
var base32 = (Unibabel||window).bufferToBase32(bin).replace(/=/g, '');
// lowercase with a space every 4 characters
var key = base32.toLowerCase().replace(/(\w{4})/g, "$1 ").trim();
return key;
}
function generateGoogleAuthKey() {
return generateOtpKey().then(encodeGoogleAuthKey);
}
// Binary-decode the key from base32 (Google Authenticator, FB, M$, etc)
function decodeGoogleAuthKey(key) {
// decode base32 google auth key to binary
var unformatted = key.replace(/\W+/g, '').toUpperCase();
var bin = (Unibabel||window).base32ToBuffer(unformatted);
return bin;
}
// Generate a Google Auth Token
function generateGoogleAuthToken(key) {
var bin = decodeGoogleAuthKey(key);
return totp.gen(bin);
}
// Verify a Google Auth Token
function verifyGoogleAuthToken(key, token) {
var bin = decodeGoogleAuthKey(key);
token = token.replace(/\W+/g, '');
// window is +/- 1 period of 30 seconds
return totp.verify(token, bin, { window: 1, time: 30 });
}
Authenticator.generateKey = generateGoogleAuthKey;
Authenticator.generateToken = generateGoogleAuthToken;
Authenticator.verifyToken = verifyGoogleAuthToken;
Authenticator.generateTotpUri = function (secret, accountName, issuer, algo, digits, period) {
// Full OTPAUTH URI spec as explained at
// https://github.com/google/google-authenticator/wiki/Key-Uri-Format
return 'otpauth://totp/'
+ encodeURI(issuer || '') + ':' + encodeURI(accountName || '')
+ '?secret=' + secret.replace(/[\s\.\_\-]+/g, '').toUpperCase()
+ '&issuer=' + encodeURIComponent(issuer || '')
+ '&algorithm=' + (algo || 'SHA1')
+ '&digits=' + (digits || 6)
+ '&period=' + (period || 30)
;
};
}(
'undefined' !== typeof window ? (window.Authenticator = {}) : module.exports
));