Sharkey/packages/backend/src/misc/secure-rndstr.ts
Shun Sakai c2370a1be6
chore: 著作権とライセンスについての情報を各ファイルに追加する (#11348)
* chore: Add the SPDX information to each file

Add copyright and licensing information as defined in version 3.0 of
the REUSE Specification.

* tweak format

---------

Co-authored-by: syuilo <Syuilotan@yahoo.co.jp>
2023-07-27 14:31:52 +09:00

25 lines
654 B
TypeScript

/*
* SPDX-FileCopyrightText: syuilo and other misskey contributors
* SPDX-License-Identifier: AGPL-3.0-only
*/
import * as crypto from 'node:crypto';
export const L_CHARS = '0123456789abcdefghijklmnopqrstuvwxyz';
const LU_CHARS = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
export function secureRndstr(length = 32, { chars = LU_CHARS } = {}): string {
const chars_len = chars.length;
let str = '';
for (let i = 0; i < length; i++) {
let rand = Math.floor((crypto.randomBytes(1).readUInt8(0) / 0xFF) * chars_len);
if (rand === chars_len) {
rand = chars_len - 1;
}
str += chars.charAt(rand);
}
return str;
}