function verify(string $key, string $nonce, string $aad, string $ciphertext, string $tag) : bool
{
$cipher = new Cipher();
$context = $cipher->init($key, $nonce);
$cipher->aad($context, $aad);
$cipher->verify($context, $ciphertext);
try {
$cipher->finish($context, $tag);
return true;
} catch (AuthenticationException $e) {
return false;
}
}
