File Content: rng-browser.js // Unique ID creation requires a high quality random # generator. In the // browser this is a little complicated due to unknown quality of Math.random() // and inconsistent support for the `crypto` API. We do the best we can via // feature-detection // getRandomValues needs to be invoked in a context where "this" is a Crypto // implementation. Also, find the complete implementation of crypto on IE11. var getRandomValues = (typeof(crypto) != 'undefined' && crypto.getRandomValues && crypto.getRandomValues.bind(crypto)) || (typeof(msCrypto) != 'undefined' && typeof window.msCrypto.getRandomValues == 'function' && msCrypto.getRandomValues.bind(msCrypto)); if (getRandomValues) { // WHATWG crypto RNG - http://wiki.whatwg.org/wiki/Crypto var rnds8 = new Uint8Array(16); // eslint-disable-line no-undef module.exports = function whatwgRNG() { getRandomValues(rnds8); return rnds8; }; } else { // Math.random()-based (RNG) // // If all else fails, use Math.random(). It's fast, but is of unspecified // quality. var rnds = new Array(16); module.exports = function mathRNG() { for (var i = 0, r; i < 16; i++) { if ((i & 0x03) === 0) r = Math.random() * 0x100000000; rnds[i] = r >>> ((i & 0x03) << 3) & 0xff; } return rnds; }; } Submit