ent socket information and the quadruple are saved in <code>sock_pair_map</code>. At the same time, the same quadruple and its corresponding original destination address will be written to <code>pair_original_dest</code>. (Cookie is not used here because it cannot be obtained in the <code>get_sockopt</code> program).</li><li>After Envoy receives the connection, it will call the <code>get_sockopt</code> function to read the destination address of the current connection. <code>get_sockopt</code> will extract 