yumechi-no-kuni/src/misc/secure-rndstr.ts

21 lines
557 B
TypeScript

import * as crypto from 'crypto';
const L_CHARS = '0123456789abcdefghijklmnopqrstuvwxyz';
const LU_CHARS = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
export function secureRndstr(length = 32, useLU = true): string {
const chars = useLU ? LU_CHARS : L_CHARS;
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;
}