able to decrypt it.</li>
<li>Check if the string is long enough, separate the HMAC out of
it and validate if it is correct (this is done in a way that
prevents timing attacks against it). Return FALSE if either of
the checks fails.</li>
<li>Base64-decode the string.</li>
<li>Separate the IV out of the cipher-text and decrypt the said
cipher-text using that IV and the derived encryption key.</li>
</ol>
</li>
</ul>
</div>
<div class="section" id="using-custom-parameters">
<span id="custom-parameters"></span><