4
string.</li>
</ol>
</li>
<li><code class="docutils literal"><span class="pre">$this-&gt;encryption-&gt;decrypt($ciphertext)</span></code><ol class="arabic">
<li>Derive an encryption key and a HMAC key from your configured
<em>encryption_key</em> via HKDF, using the SHA-512 digest algorithm.
Because your configured <em>encryption_key</em> is the same, this
will produce the same result as in the <code class="docutils literal"><span class="pre">encrypt()</span></code> method
above - otherwise you won’t be 