import { createHmac } from 'node:crypto'; import { concat, uint64be } from '../lib/buffer_utils.js'; export default function cbcTag(aad, iv, ciphertext, macSize, macKey, keySize) { const macData = concat(aad, iv, ciphertext, uint64be(aad.length << 3)); const hmac = createHmac(`sha${macSize}`, macKey); hmac.update(macData); return hmac.digest().slice(0, keySize >> 3); }