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/*
*
* (C) 2013-14 - ntop.org
*
*
* 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 3 of the License, 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; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#include "ntop_includes.h"
// #define ALERT_DEBUG 1
/* *************************************** */
AlertCounter::AlertCounter(u_int16_t _max_num_hits_sec,
u_int8_t _over_threshold_duration_sec) {
max_num_hits_sec = _max_num_hits_sec;
over_threshold_duration_sec = _over_threshold_duration_sec;
if(over_threshold_duration_sec < 1) over_threshold_duration_sec = 1;
init();
}
/* *************************************** */
void AlertCounter::init() {
time_last_hit = time_last_alert_reported = 0;
num_hits_rcvd_last_second = 0;
last_trepassed_threshold = 0, num_trepassed_threshold = 0;
num_hits_since_first_alert = 0;
}
/* *************************************** */
bool AlertCounter::incHits(time_t when) {
if(time_last_hit < (when-1))
init(); /* Only consecutive alerts matter */
else if(time_last_hit == (when-1))
num_hits_rcvd_last_second = 0;
num_hits_rcvd_last_second++, num_hits_since_first_alert++, time_last_hit = when;
if((num_hits_rcvd_last_second > max_num_hits_sec)
&& (last_trepassed_threshold != when)) {
num_trepassed_threshold++, last_trepassed_threshold = when;
#ifdef ALERT_DEBUG
ntop->getTrace()->traceEvent(TRACE_NORMAL,
"Trepass [num: %u][last: %u][now: %u][duration: %u]",
num_trepassed_threshold, last_trepassed_threshold, when,
over_threshold_duration_sec);
#endif
if(num_trepassed_threshold > over_threshold_duration_sec) {
#ifdef ALERT_DEBUG
ntop->getTrace()->traceEvent(TRACE_NORMAL,
"Alarm triggered [num: %u][last: %u][now: %u][duration: %u]",
num_trepassed_threshold, last_trepassed_threshold, when,
over_threshold_duration_sec);
#endif
if(when > (time_last_alert_reported+CONST_ALERT_GRACE_PERIOD)) {
#ifdef ALERT_DEBUG
ntop->getTrace()->traceEvent(TRACE_NORMAL,
"Alert emitted [num: %u][now: %u][duration: %u][tot_hits: %u]",
num_trepassed_threshold, when,
over_threshold_duration_sec, num_hits_since_first_alert);
#endif
time_last_alert_reported = when;
return(true);
}
}
}
return(false);
}
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