ntopng/src/AlertCounter.cpp

110 lines
3.6 KiB
C++

/*
*
* (C) 2013-19 - 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() {
trailing_window_max_since_hits_reset = 0;
hits_reset_req = false;
reset_window();
}
/* *************************************** */
void AlertCounter::reset_window(time_t when) {
memset(&trailing_window, 0, sizeof(trailing_window));
trailing_window_min = 0;
trailing_index = 0;
time_last_hit = when;
}
/* *************************************** */
void AlertCounter::inc(time_t when, AlertableEntity *alertable) {
if(hits_reset_req) { /* Reset the maximum as requested and start over */
trailing_window_max_since_hits_reset = 0;
hits_reset_req = false;
reset_window(when);
}
if(when - time_last_hit > 1) /* Only consecutive hits matter */
reset_window(when);
if(when - time_last_hit) { /* If true, difference must be 1 as reset_window(when) is called if > 1 */
u_int16_t tmp_min = trailing_window[0]; /* Update the minimum value to make sure all the elements in the window are >= */
for(u_int8_t i = 1; i < ALERT_COUNTER_WINDOW_SECS; i++) {
if(trailing_window[i] < tmp_min /* New minimum detected */)
tmp_min = trailing_window[i];
}
trailing_window_min = tmp_min;
/* Update the overall maximum of minima since reset */
if(trailing_window_min > trailing_window_max_since_hits_reset)
trailing_window_max_since_hits_reset = trailing_window_min;
trailing_index = (trailing_index + 1) % ALERT_COUNTER_WINDOW_SECS; /* Move to the next element in the array */
trailing_window[trailing_index] = 0; /* Reset as it could contain old values */
time_last_hit = when; /* Update the last hit */
}
if(trailing_window[trailing_index] < (u_int16_t)-1) /* Protect against wraps */
trailing_window[trailing_index]++;
#if 0
char buf[256];
ntop->getTrace()->traceEvent(TRACE_NORMAL,
"stats [host: %s][when: %u][time_last_hit: %u][trailing_window_max_since_hits_reset: %u][trailing_window_min: %u]"
"[trailing_window[cur]: %u][trailing_window[cur-1]: %u][trailing_window[cur-2]: %u]",
h->get_ip()->print(buf, sizeof(buf)),
alertable->getEntityValue()->c_str(),
when,
time_last_hit,
trailing_window_max_since_hits_reset,
trailing_window_min,
trailing_window[trailing_index],
trailing_window[(trailing_index + 2) % ALERT_COUNTER_WINDOW_SECS],
trailing_window[(trailing_index + 1) % ALERT_COUNTER_WINDOW_SECS]
);
#endif
}
/* *************************************** */
u_int16_t AlertCounter::hits() const {
if(hits_reset_req) /* Requested, but not yet reset */
return 0;
return trailing_window_max_since_hits_reset;
}
/* *************************************** */
void AlertCounter::reset_hits() {
hits_reset_req = true;
}