42 lines
1.2 KiB
TypeScript
42 lines
1.2 KiB
TypeScript
'use strict';
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import { arrayify } from '../utils/bytes';
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import { defineReadOnly } from '../utils/properties';
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let crypto: any = (<any>global).crypto || (<any>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: Uint8Array): Uint8Array {
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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] ^= Math.trunc(256 * Math.random());
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} else {
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buffer[i] = Math.trunc(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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export function randomBytes(length: number): Uint8Array {
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if (length <= 0 || length > 1024 || parseInt(String(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 arrayify(result);
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};
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if (crypto._weakCrypto === true) {
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defineReadOnly(randomBytes, '_weakCrypto', true);
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}
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