private boolean isKnownPlugin(String url) {
        for (String pluginName : availablePlugins.keySet()) {
            if (availablePlugins.get(pluginName).getDownloadURL().toString().equals(url)) {
                return true;
            }
        }
        
        return false;
    }
Check if the plugin URL is in the known list of available plugins.

i.e. that it's an approved download source.

@param url The URL of the plugin to download.
@return true if the URL is in the list. Otherwise false.
xmppserver/src/main/java/org/jivesoftware/openfire/update/UpdateManager.java