/*****
*
* Copyright (C) 2002 Vincent Glaume <glaume@enseirb.fr>, Baptiste Malguy <baptiste@malguy.net>
* All Rights Reserved
*
* This file is part of the Prelude program.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by 
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING.  If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*
*****/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>
#include <dlfcn.h>
#include <errno.h>
#include <sys/time.h>
#include <inttypes.h>

#include <libprelude/list.h>
#include <libprelude/prelude-io.h>
#include <libprelude/prelude-message.h>
#include <libprelude/prelude-log.h>
#include <libprelude/plugin-common.h>
#include <libprelude/plugin-common-prv.h>
#include <libprelude/idmef-tree.h>

#include "plugin-cm-trigger.h"


static LIST_HEAD(cm_trigger_plugins_list);

/*
 * We may have several CM triggering plugins subscribed but only one must be used for a given alert
 * we call it the valid plugin, and it is stored in the following var:
 */
static plugin_container_t *valid_cm_trigger_plugin = NULL;


/*
 *
 */
static int subscribe(plugin_container_t *pc) 
{
        if ( !valid_cm_trigger_plugin ) {
                valid_cm_trigger_plugin = pc;
                log(LOG_INFO, "- Subscribing and selecting %s to activate counter-measure triggering plugins.\n", 
                    pc->plugin->name);
        } else
                log(LOG_INFO, "- Subscribing %s to activate counter-measure triggering plugins.\n", pc->plugin->name);
        return plugin_add(pc, &cm_trigger_plugins_list, NULL);
}


static void unsubscribe(plugin_container_t *pc) 
{
        log(LOG_INFO, "- Un-subscribing %s from active counter-measure plugins.\n", pc->plugin->name);
        plugin_del(pc);
        if ( !list_empty(&cm_trigger_plugins_list) ) {
                valid_cm_trigger_plugin = list_entry(&cm_trigger_plugins_list, plugin_container_t, ext_list);
                log(LOG_INFO, "\tNew selected counter-measure triggering plugin is %s.\n", 
                    valid_cm_trigger_plugin->plugin->name);
        } else
                valid_cm_trigger_plugin = NULL;
        
}




int cm_trigger_plugin_run(idmef_alert_t *msg)
{
        int ret;
        plugin_run_with_return_value(valid_cm_trigger_plugin, plugin_cm_trigger_t, run, ret, msg);
        return ret;
}



/*
 * Open the plugin directory (dirname),
 * and try to load all plugins located in it.
 */
int cm_trigger_plugins_init(const char *dirname, int argc, char **argv)
{
        int ret;
        
        ret = plugin_load_from_dir(dirname, argc, argv, subscribe, unsubscribe);

        /*
         * don't return an error if the report directory doesn't exist.
         * this could happen as it's normal to not use report plugins on
         * certain system.
         */
        if ( ret < 0 && errno != ENOENT ) {
                log(LOG_ERR, "couldn't load plugin subsystem.\n");
                return -1;
        }
        
        return ret;
}




/*
 * report_plugins_available:
 *
 * Returns: 0 if there is active REPORT plugins, -1 otherwise.
 */
int cm_trigger_plugin_available(void) 
{
        return ( list_empty(&cm_trigger_plugins_list) || !valid_cm_trigger_plugin) ? -1 : 0;
}