Function decrypt

app/lib/crypto.ts:26–44

(key: string, payload: string)

}

export async function decrypt(key: string, payload: string) {
  const bundle = encodeBase64(payload);

  const iv = new Uint8Array(bundle.buffer, bundle.byteLength - IV_LENGTH);
  const ciphertext = new Uint8Array(bundle.buffer, 0, bundle.byteLength - IV_LENGTH);

  const cryptoKey = await getKey(key);

  const plaintext = await crypto.subtle.decrypt(
    {
      name: 'AES-CBC',
      iv,
    },
    cryptoKey,
    ciphertext,
  );

  return decoder.decode(plaintext);
}

async function getKey(key: string) {
  return await crypto.subtle.importKey('raw', encodeBase64(key), { name: 'AES-CBC' }, false, ['encrypt', 'decrypt']);