44 lines
1.2 KiB
JavaScript
44 lines
1.2 KiB
JavaScript
'use strict';
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var convert = require('./convert');
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var defineProperty = require('./properties').defineProperty;
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var crypto = global.crypto || global.msCrypto;
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if (!crypto || !crypto.getRandomValues) {
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console.log('WARNING: Missing strong random number source; using weak randomBytes');
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crypto = {
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getRandomValues: function(buffer) {
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for (var round = 0; round < 20; round++) {
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for (var i = 0; i < buffer.length; i++) {
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if (round) {
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buffer[i] ^= parseInt(256 * Math.random());
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} else {
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buffer[i] = parseInt(256 * Math.random());
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}
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}
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}
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return buffer;
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},
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_weakCrypto: true
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};
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}
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function randomBytes(length) {
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if (length <= 0 || length > 1024 || parseInt(length) != length) {
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throw new Error('invalid length');
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}
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var result = new Uint8Array(length);
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crypto.getRandomValues(result);
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return convert.arrayify(result);
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};
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if (crypto._weakCrypto === true) {
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defineProperty(randomBytes, '_weakCrypto', true);
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}
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module.exports = randomBytes;
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