deno/cli/js/get_random_values.ts
2020-01-02 15:13:47 -05:00

31 lines
936 B
TypeScript

// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
import * as dispatch from "./dispatch.ts";
import { sendSync } from "./dispatch_json.ts";
import { assert } from "./util.ts";
/** Synchronously collects cryptographically secure random values. The
* underlying CSPRNG in use is Rust's `rand::rngs::ThreadRng`.
*
* const arr = new Uint8Array(32);
* crypto.getRandomValues(arr);
*/
export function getRandomValues<
T extends
| Int8Array
| Uint8Array
| Uint8ClampedArray
| Int16Array
| Uint16Array
| Int32Array
| Uint32Array
>(typedArray: T): T {
assert(typedArray !== null, "Input must not be null");
assert(typedArray.length <= 65536, "Input must not be longer than 65536");
const ui8 = new Uint8Array(
typedArray.buffer,
typedArray.byteOffset,
typedArray.byteLength
);
sendSync(dispatch.OP_GET_RANDOM_VALUES, {}, ui8);
return typedArray;
}