@Override
    protected void processMessage(Message packet) throws UnauthorizedException {
        // Overwrite the FROM attribute to avoid spoofing
        packet.setFrom(session.getAddress());
        super.processMessage(packet);
    }
Handler of XML stanzas sent by clients connected directly to the server. Received packet will
have their FROM attribute overridden to avoid spoofing.<p>

By default, the hostname specified in the stream header sent by clients will not be validated.
When validated the TO attribute of the stream header has to match the server name or a valid
subdomain. If the value of the 'to' attribute is not valid then a host-unknown error
will be returned. To enable the validation set the system property
<b>xmpp.client.validate.host</b> to true.

@author Gaston Dombiak
xmppserver/src/main/java/org/jivesoftware/openfire/net/ClientStanzaHandler.java