ntopng/src/IEC104Stats.cpp
2026-03-15 10:50:50 +01:00

528 lines
16 KiB
C++

/*
*
* (C) 2013-26 - 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"
#include "flow_alerts_includes.h"
/*
#define DEBUG_IEC60870
#define IEC60870_TRACE
*/
#define CLIENT_ALERT_SCORE 90
#define SERVER_ALERT_SCORE 10
/* *************************************** */
IEC104Stats::IEC104Stats() {
if (trace_new_delete)
ntop->getTrace()->traceEvent(TRACE_NORMAL, "[new] %s", __FILE__);
memset(&pkt_lost, 0, sizeof(pkt_lost));
last_type_i = 0;
memset(&last_i_apdu, 0, sizeof(last_i_apdu));
memset(&stats, 0, sizeof(stats));
memset(&transitions, 0, sizeof(transitions));
i_s_apdu = ndpi_alloc_data_analysis(32 /* sliding window side */);
tx_seq_num = rx_seq_num = 0, infobuf[0] = '\0';
invalid_command_transition_detected = false;
}
/* *************************************** */
IEC104Stats::~IEC104Stats() {
if (trace_new_delete)
ntop->getTrace()->traceEvent(TRACE_NORMAL, "[new] %s", __FILE__);
ndpi_free_data_analysis(i_s_apdu, 1);
}
/* *************************************** */
void IEC104Stats::processPacket(Flow* f, bool tx_direction,
const u_char* payload, u_int16_t payload_len,
const struct pcap_pkthdr* h) {
if ((payload_len >= 6) && (payload[0] == 0x68 /* IEC magic byte */)) {
u_int offset = 1 /* Skip magic byte */;
u_int64_t* allowedTypeIDs = ntop->getPrefs()->getIEC104AllowedTypeIDs();
std::unordered_map<u_int16_t, u_int32_t>::iterator it;
lock.wrlock(__FILE__, __LINE__);
if (tx_direction)
stats.forward_msgs++;
else
stats.reverse_msgs++;
while ((offset + 1) /* Skip START byte */ < payload_len) {
/* https://infosys.beckhoff.com/english.php?content=../content/1033/tcplclibiec870_5_104/html/tcplclibiec870_5_104_objref_overview.htm&id
*/
u_int8_t len = payload[offset];
u_int8_t pdu_type = ((payload[offset + 1] & 0x01) == 0)
? 0
: (payload[offset + 1] & 0x03);
#ifdef DEBUG_IEC60870
ntop->getTrace()->traceEvent(TRACE_WARNING, "[%s] %02X %02X %02X %02X",
__FUNCTION__, payload[offset - 1],
payload[offset], payload[offset + 1],
payload[offset + 2]);
#endif
#ifdef DEBUG_IEC60870
ntop->getTrace()->traceEvent(
TRACE_WARNING, "[%s] A-PDU Len %u/%u [pdu_type: %u][magic: %02X]",
__FUNCTION__, len, payload_len, pdu_type, payload[offset - 1]);
#endif
if (len == 0) break; /* Something went wrong */
switch (pdu_type) {
case 0x03: /* U */
{
u_int8_t u_type = (payload[offset + 1] & 0xFC) >> 2;
const char* u_type_str;
#ifdef IEC60870_TRACE
ntop->getTrace()->traceEvent(TRACE_NORMAL, "A-PDU U-%u",
(payload[offset + 1] & 0xFC) >> 2);
#endif
/* No rx and tx to be updated */
stats.type_u++;
switch (u_type) {
case 0x01:
u_type_str = "STARTDT act";
break;
case 0x02:
u_type_str = "STARTDT con";
break;
case 0x04:
u_type_str = "STOPDT act";
break;
case 0x08:
u_type_str = "STOPDT con";
break;
case 0x10:
u_type_str = "TESTFR act";
break;
case 0x20:
u_type_str = "TESTFR con";
break;
default:
u_type_str = "???";
break;
}
snprintf(infobuf, sizeof(infobuf) - 1, "%s U (%s)",
tx_direction ? "->" : "<-", u_type_str);
} break;
case 0x01: /* S */
if ((offset + 4) < payload_len) {
if (len >= 4) {
u_int16_t rx = ((((u_int16_t)payload[offset + 4]) << 8) +
payload[offset + 3]) >>
1;
if (last_i_apdu.tv_sec != 0) {
float ms = Utils::msTimevalDiff(&h->ts, &last_i_apdu);
#ifdef IEC60870_TRACE
ntop->getTrace()->traceEvent(
TRACE_NORMAL,
"A-PDU S [last I-TX: %u][S RX ack: %u][tdiff: %.2f msec]",
tx_seq_num, rx, ms);
#endif
/*
In theory if all is in good shape
(rx + 1) == tx_seq_num
*/
ndpi_data_add_value(i_s_apdu, ms);
}
/* No rx and tx to be updated */
snprintf(infobuf, sizeof(infobuf) - 1, "%s S, RX %u",
tx_direction ? "->" : "<-", rx);
}
stats.type_s++;
}
break;
}
if (pdu_type != 0x0 /* Type I */) {
offset += len + 2;
stats.type_other++;
continue;
}
/* From now on, only Type I packets are processed */
memcpy(&last_i_apdu, &h->ts, sizeof(struct timeval));
stats.type_i++;
if (((offset + 6) < payload_len) &&
(len >= 6 /* Ignore 4 bytes APDUs */)) {
u_int16_t rx_value, tx_value;
bool initial_run =
((rx_seq_num == 0) && (tx_seq_num == 0)) ? true : false;
tx_value =
((((u_int16_t)payload[offset + 2]) << 8) + payload[offset + 1]) >>
1;
rx_value =
((((u_int16_t)payload[offset + 4]) << 8) + payload[offset + 3]) >>
1;
if (!tx_direction) {
/* Counters are swapped */
u_int16_t v = rx_value;
rx_value = tx_value;
tx_value = v;
}
if ((tx_value == tx_seq_num) && (rx_value == rx_seq_num)) {
stats.retransmitted_msgs++;
lock.unlock(__FILE__, __LINE__);
return;
}
if (!initial_run) {
u_int32_t diff = abs(tx_value - (tx_seq_num + 1));
/* Check for id reset (16 bit only) */
if (diff != 32768) pkt_lost.tx += diff;
}
tx_seq_num = tx_value;
if (!tx_direction) {
if (!initial_run) {
u_int32_t diff = abs(rx_value - rx_seq_num);
/* Check for id reset (16 bit only) */
if (diff != 32768) pkt_lost.rx += diff;
}
rx_value++; /* The next RX will be increased by 1 */
} else {
if (!initial_run) {
u_int32_t diff = abs(rx_value - rx_seq_num);
/* Check for id reset (16 bit only) */
if (diff != 32768) pkt_lost.rx += diff;
}
}
rx_seq_num = rx_value;
/* Skip magic(1), len(1), type/TX(2), RX(2) = 6 */
len -= 6 /* Skip magic and len */,
offset += 5 /* magic already skept */;
if (payload_len >= (offset + len)) {
u_int8_t type_id = payload[offset];
u_int8_t cause_tx = payload[offset + 1] & 0x3F;
u_int8_t negative =
((payload[offset + 1] & 0x40) == 0x40) ? true : false;
u_int16_t asdu;
u_int64_t bit;
bool unexpected_typeid_alerted = false;
offset += len + 2 /* magic and len */;
if ((len >= 6) && ((offset + 6) <= payload_len))
asdu = /* ntohs */ (*((u_int16_t*)&payload[4 + offset]));
else
asdu = 0;
#ifdef DEBUG_IEC60870
ntop->getTrace()->traceEvent(
TRACE_WARNING, "[%s] TypeId %u [offset %u/%u]", __FUNCTION__,
type_id, offset, payload_len);
#endif
#ifdef IEC60870_TRACE
ntop->getTrace()->traceEvent(
TRACE_NORMAL,
"[%s] A-PDU I-%-3u [rx: %u][tx: %u][lost rx/tx: %u/%u]",
tx_direction ? "->" : "<-", type_id, rx_seq_num, tx_seq_num,
pkt_lost.rx, pkt_lost.tx);
#endif
snprintf(infobuf, sizeof(infobuf) - 1, "%s I, RX %u, TX %u",
tx_direction ? "->" : "<-", rx_seq_num, tx_seq_num);
if (!initial_run) {
u_int32_t transition = (last_type_i << 8) + type_id;
it = type_i_transitions.find(transition);
if (it == type_i_transitions.end()) {
if (f->get_duration() >
ntop->getPrefs()->getIEC60870LearingPeriod()) {
FlowAlert* alert = NULL;
u_int16_t c_score = 50, s_score = 10;
#ifdef IEC60870_TRACE
ntop->getTrace()->traceEvent(TRACE_NORMAL,
"Found new transition %u -> %u",
last_type_i, type_id);
#endif
char key[128], rsp[64];
snprintf(key, sizeof(key), CHECKS_IEC_INVALID_TRANSITION);
if ((!ntop->getRedis()->get(key, rsp, sizeof(rsp))) &&
((rsp[0] != '\0') && (!strcmp(rsp, "1"))))
alert = new IECInvalidTransitionAlert(
NULL, f, (struct timeval*)&h->ts, last_type_i, type_id);
if (alert) {
alert->setCliSrvScores(c_score, s_score);
f->triggerAlert(alert, true);
}
type_i_transitions[transition] = 2; /* Post Learning */
} else
type_i_transitions[transition] = 1; /* During Learning */
} else
type_i_transitions[transition] = it->second + 1;
}
if (!initial_run) {
if (isMonitoringTypeId(last_type_i) && isMonitoringTypeId(type_id))
transitions.m_to_m++;
else if (isMonitoringTypeId(last_type_i) &&
isCommandTypeId(type_id))
transitions.m_to_c++;
else if (isCommandTypeId(last_type_i) &&
isMonitoringTypeId(type_id))
transitions.c_to_m++;
else if (isCommandTypeId(last_type_i) && isCommandTypeId(type_id))
transitions.c_to_c++;
if ((invalid_command_transition_detected == false) &&
((transitions.m_to_c > 20) || (transitions.c_to_m > 20) ||
(transitions.c_to_c > 5))) {
/* https://github.com/ntop/ntopng/issues/6598 */
FlowAlert* alert = NULL;
u_int16_t c_score = CLIENT_ALERT_SCORE,
s_score = SERVER_ALERT_SCORE;
char key[128], rsp[64];
snprintf(key, sizeof(key), CHECKS_IEC_INVALID_COMMAND_TRANSITION);
if ((!ntop->getRedis()->get(key, rsp, sizeof(rsp))) &&
((rsp[0] != '\0') && (!strcmp(rsp, "1"))))
alert = new IECInvalidCommandTransitionAlert(
NULL, f, (struct timeval*)&h->ts, transitions.m_to_c,
transitions.c_to_m, transitions.c_to_c);
if (alert) {
alert->setCliSrvScores(c_score, s_score);
f->triggerAlert(alert, true);
}
// ntop->getTrace()->traceEvent(TRACE_WARNING, "*** INVALID
// TRANSITION %u -> %u", last_type_i, type_id);
invalid_command_transition_detected = true;
}
}
last_type_i = type_id;
it = typeid_uses.find(type_id);
if (it == typeid_uses.end())
typeid_uses[type_id] = 1;
else
typeid_uses[type_id] = it->second + 1;
if (type_id < 64) {
bit = ((u_int64_t)1) << type_id;
if ((allowedTypeIDs[0] & bit) == 0)
unexpected_typeid_alerted = true;
} else if (type_id < 128) {
bit = ((u_int64_t)1) << (type_id - 64);
if ((allowedTypeIDs[1] & bit) == 0)
unexpected_typeid_alerted = true;
}
if (unexpected_typeid_alerted) {
FlowAlert* alert = NULL;
u_int16_t c_score = CLIENT_ALERT_SCORE,
s_score = SERVER_ALERT_SCORE;
char key[128], rsp[64];
snprintf(key, sizeof(key), CHECKS_IEC_UNEXPECTED_TYPE_ID);
if ((!ntop->getRedis()->get(key, rsp, sizeof(rsp))) &&
((rsp[0] != '\0') && (!strcmp(rsp, "1"))))
alert = new IECUnexpectedTypeIdAlert(NULL, f, type_id, asdu,
cause_tx, negative);
if (alert) {
alert->setCliSrvScores(c_score, s_score);
f->triggerAlert(alert, true);
}
} /* unexpected_typeid_alerted */
/* Discard typeIds 127..255 */
} else /* payload_len < len */
break;
} else {
// ntop->getTrace()->traceEvent(TRACE_WARNING, "*** short APDUs");
break;
}
if ((offset < payload_len) &&
(payload[offset] == 0x68 /* IEC magic byte */))
offset += 1; /* We skip the initial magic byte */
else {
#ifdef DEBUG_IEC60870
ntop->getTrace()->traceEvent(
TRACE_WARNING, "Skipping IEC entry: no magic byte @ offset %u",
offset);
#endif
break;
}
} /* while */
lock.unlock(__FILE__, __LINE__);
}
}
/* *************************************** */
void IEC104Stats::lua(lua_State* vm) {
lua_newtable(vm);
lock.rdlock(__FILE__, __LINE__);
/* *************************** */
lua_newtable(vm);
for (std::unordered_map<u_int16_t, u_int32_t>::iterator it =
typeid_uses.begin();
it != typeid_uses.end(); ++it) {
char buf[8];
snprintf(buf, sizeof(buf), "%u", it->first);
lua_push_int32_table_entry(vm, buf, it->second);
}
lua_pushstring(vm, "typeid");
lua_insert(vm, -2);
lua_settable(vm, -3);
/* *************************** */
lua_newtable(vm);
for (std::unordered_map<u_int16_t, u_int32_t>::iterator it =
type_i_transitions.begin();
it != type_i_transitions.end(); ++it) {
char buf[8];
snprintf(buf, sizeof(buf), "%u,%u", (it->first >> 8), it->first & 0xFF);
lua_push_int32_table_entry(vm, buf, it->second);
}
lua_pushstring(vm, "typeid_transitions");
lua_insert(vm, -2);
lua_settable(vm, -3);
lock.unlock(__FILE__, __LINE__);
/* *************************** */
lua_newtable(vm);
lua_push_int32_table_entry(vm, "type_i", stats.type_i);
lua_push_int32_table_entry(vm, "type_s", stats.type_s);
lua_push_int32_table_entry(vm, "type_u", stats.type_u);
lua_push_int32_table_entry(vm, "type_other", stats.type_other);
lua_push_int32_table_entry(vm, "forward_msgs", stats.forward_msgs);
lua_push_int32_table_entry(vm, "reverse_msgs", stats.reverse_msgs);
lua_push_int32_table_entry(vm, "retransmitted_msgs",
stats.retransmitted_msgs);
lua_pushstring(vm, "stats");
lua_insert(vm, -2);
lua_settable(vm, -3);
/* *************************** */
lua_newtable(vm);
lua_push_int32_table_entry(vm, "rx", pkt_lost.rx);
lua_push_int32_table_entry(vm, "tx", pkt_lost.tx);
lua_pushstring(vm, "pkt_lost");
lua_insert(vm, -2);
lua_settable(vm, -3);
/* *************************** */
lua_newtable(vm);
lua_push_float_table_entry(vm, "average", ndpi_data_average(i_s_apdu));
lua_push_float_table_entry(vm, "stddev", ndpi_data_stddev(i_s_apdu));
lua_pushstring(vm, "ack_time");
lua_insert(vm, -2);
lua_settable(vm, -3);
/* *************************** */
lua_pushstring(vm, "iec104");
lua_insert(vm, -2);
lua_settable(vm, -3);
}
/* *************************************** */
std::string IEC104Stats::getFlowInfo() {
lock.rdlock(__FILE__, __LINE__);
std::string info_field = std::string(infobuf);
lock.unlock(__FILE__, __LINE__);
return info_field;
}
/* *************************************** */
bool IEC104Stats::isMonitoringTypeId(u_int16_t tid) {
return (((tid <= 40) || (tid == 70)) ? true : false);
}
/* *************************************** */
bool IEC104Stats::isCommandTypeId(u_int16_t tid) {
if (((tid >= 45) && (tid <= 64)) || ((tid >= 100) && (tid <= 107)))
return (true);
else
return (false);
}
/* *************************************** */