How to Implement SCADA Network Security in OMNeT++
To implement the SCADA (Supervisory Control and Data Acquisition) network security in OMNeT++ contains making a simulation of a SCADA network, executing security mechanisms to protect it, and analysis it against potential threats. Given below is a procedure with examples on how to set up and implement SCADA network security in OMNeT++.
Step-by-Step Implementations:
- Define the SCADA Network Topology
Initially, describe a network topology that signifies a usual SCADA system. It might contain components like the HMI (Human-Machine Interface), the SCADA server, RTUs (Remote Terminal Units), and PLCs (Programmable Logic Controllers).
network SCADASecurityNetwork
{
submodules:
rtu1: StandardHost {
@display(“p=100,100”);
}
rtu2: StandardHost {
@display(“p=100,200”);
}
plc1: StandardHost {
@display(“p=300,100”);
}
plc2: StandardHost {
@display(“p=300,200”);
}
scadaServer: StandardHost {
@display(“p=500,150”);
}
hmi: StandardHost {
@display(“p=700,150”);
}
firewall: Router {
@display(“p=400,250”);
}
connections:
rtu1.ethg++ <–> Eth100M <–> plc1.ethg++;
rtu2.ethg++ <–> Eth100M <–> plc2.ethg++;
plc1.ethg++ <–> Eth100M <–> scadaServer.ethg++;
plc2.ethg++ <–> Eth100M <–> scadaServer.ethg++;
scadaServer.ethg++ <–> Eth100M <–> firewall.ethg++;
firewall.ethg++ <–> Eth100M <–> hmi.ethg++;
}
- Implement SCADA Communication Protocol
In SCADA networks, usual communication protocols contain Modbus, DNP3, or custom industrial protocols. For simplicity, let’s make a simple custom protocol to mimic communication among the SCADA server, PLCs, and RTUs.
// SCADAProtocolApp.cc
#include <omnetpp.h>
#include “inet/applications/tcpapp/TcpAppBase.h”
using namespace omnetpp;
using namespace inet;
class SCADAProtocolApp : public TcpAppBase
{
protected:
virtual void initialize(int stage) override;
virtual void handleMessageWhenUp(cMessage *msg) override;
void sendRTUData();
void controlPLC();
};
Define_Module(SCADAProtocolApp);
void SCADAProtocolApp::initialize(int stage)
{
TcpAppBase::initialize(stage);
if (stage == inet::INITSTAGE_APPLICATION_LAYER) {
if (strcmp(getParentModule()->getName(), “rtu1”) == 0 || strcmp(getParentModule()->getName(), “rtu2”) == 0) {
scheduleAt(simTime() + 1, new cMessage(“sendRTUData”));
} else if (strcmp(getParentModule()->getName(), “scadaServer”) == 0) {
scheduleAt(simTime() + 2, new cMessage(“controlPLC”));
}
}
}
void SCADAProtocolApp::handleMessageWhenUp(cMessage *msg)
{
if (strcmp(msg->getName(), “sendRTUData”) == 0) {
sendRTUData();
delete msg;
} else if (strcmp(msg->getName(), “controlPLC”) == 0) {
controlPLC();
delete msg;
} else {
TcpAppBase::handleMessageWhenUp(msg);
}
}
void SCADAProtocolApp::sendRTUData()
{
EV << “Sending RTU data to PLC…” << endl;
sendRequest(“RTUData: Value=456\r\n”);
}
void SCADAProtocolApp::controlPLC()
{
EV << “Sending control command to PLC…” << endl;
sendRequest(“ControlCommand: OpenValve\r\n”);
}
- Implement Security Measures
Familiarize security mechanisms like intrusion detection systems (IDS), firewalls, and secure communication protocols to defend the SCADA network.
Firewall Implementation
Execute a simple firewall that clarifies traffic depends on predefined rules.
// SCADAFirewall.cc
#include <omnetpp.h>
#include “inet/common/INETDefs.h”
#include “inet/common/packet/Packet.h”
#include “inet/networklayer/ipv4/Ipv4Header_m.h”
using namespace omnetpp;
using namespace inet;
class SCADAFirewall : public cSimpleModule
{
protected:
virtual void initialize() override;
virtual void handleMessage(cMessage *msg) override;
bool isAllowed(Packet *packet);
};
Define_Module(SCADAFirewall);
void SCADAFirewall::initialize()
{
EV << “SCADA Firewall Initialized” << endl;
}
void SCADAFirewall::handleMessage(cMessage *msg)
{
if (Packet *packet = dynamic_cast<Packet *>(msg)) {
if (isAllowed(packet)) {
send(packet, “out”);
} else {
EV << “Packet dropped by firewall.” << endl;
delete packet;
}
}
}
bool SCADAFirewall::isAllowed(Packet *packet)
{
const auto& networkHeader = packet->peekAtFront<Ipv4Header>();
std::string source = networkHeader->getSrcAddress().str();
std::string destination = networkHeader->getDestAddress().str();
// Example: Block traffic from certain sources or to specific ports
if (source == “192.168.1.100” || destination == “192.168.1.200”) {
return false; // Block traffic
}
return true; // Allow all other traffic
}
Intrusion Detection System (IDS)
Execute an IDS to observe traffic for suspicious activities, like unauthorized access or anomalous behaviour.
// SCADAIDS.cc
#include <omnetpp.h>
#include “inet/common/INETDefs.h”
#include “inet/common/packet/Packet.h”
#include “inet/networklayer/ipv4/Ipv4Header_m.h”
using namespace omnetpp;
using namespace inet;
class SCADAIDS : public cSimpleModule
{
protected:
virtual void initialize() override;
virtual void handleMessage(cMessage *msg) override;
void detectIntrusion(Packet *packet);
void logSecurityEvent(const std::string &event);
};
Define_Module(SCADAIDS);
void SCADAIDS::initialize()
{
EV << “SCADA IDS Initialized” << endl;
}
void SCADAIDS::handleMessage(cMessage *msg)
{
if (Packet *packet = dynamic_cast<Packet *>(msg)) {
detectIntrusion(packet);
}
send(msg, “out”);
}
void SCADAIDS::detectIntrusion(Packet *packet)
{
const auto& networkHeader = packet->peekAtFront<Ipv4Header>();
std::string source = networkHeader->getSrcAddress().str();
std::string destination = networkHeader->getDestAddress().str();
// Example: Detect unauthorized access attempts
if (source == “10.0.0.100” && destination == “192.168.1.200”) {
logSecurityEvent(“Unauthorized access attempt detected from ” + source + ” to ” + destination);
}
}
void SCADAIDS::logSecurityEvent(const std::string &event)
{
EV << “SCADA Security Event: ” << event << endl;
// Additional logging to files or alerts can be implemented here
}
- Integrate Security Measures into the SCADA Network
Incorporate the SCADAFirewall and SCADAIDS modules into the SCADA network to defend and watch the traffic.
network SCADASecurityNetwork
{
submodules:
rtu1: StandardHost {
@display(“p=100,100”);
}
rtu2: StandardHost {
@display(“p=100,200”);
}
plc1: StandardHost {
@display(“p=300,100”);
}
plc2: StandardHost {
@display(“p=300,200”);
}
scadaServer: StandardHost {
@display(“p=500,150”);
}
hmi: StandardHost {
@display(“p=700,150”);
}
firewall: SCADAFirewall {
@display(“p=400,250”);
}
ids: SCADAIDS {
@display(“p=600,250”);
}
connections:
rtu1.ethg++ <–> Eth100M <–> plc1.ethg++;
rtu2.ethg++ <–> Eth100M <–> plc2.ethg++;
plc1.ethg++ <–> Eth100M <–> scadaServer.ethg++;
plc2.ethg++ <–> Eth100M <–> scadaServer.ethg++;
scadaServer.ethg++ <–> Eth100M <–> firewall.ethg++;
firewall.ethg++ <–> Eth100M <–> hmi.ethg++;
ids.in++ <–> hmi.ethg++;
ids.out++ <–> scadaServer.ethg++;
}
- Simulate Security Threats
Mimic a range of security threats to check the SCADA network’s security mechanisms, like command injection, or replay attacks, unauthorized access.
// SCADAThreatSimulation.cc
#include <omnetpp.h>
#include “inet/applications/tcpapp/TcpAppBase.h”
using namespace omnetpp;
using namespace inet;
class SCADAThreatSimulation : public TcpAppBase
{
protected:
virtual void initialize(int stage) override;
virtual void handleMessageWhenUp(cMessage *msg) override;
void simulateUnauthorizedAccess();
void simulateCommandInjection();
};
Define_Module(SCADAThreatSimulation);
void SCADAThreatSimulation::initialize(int stage)
{
TcpAppBase::initialize(stage);
if (stage == inet::INITSTAGE_APPLICATION_LAYER) {
scheduleAt(simTime() + 3, new cMessage(“unauthorizedAccess”));
scheduleAt(simTime() + 5, new cMessage(“commandInjection”));
}
}
void SCADAThreatSimulation::handleMessageWhenUp(cMessage *msg)
{
if (strcmp(msg->getName(), “unauthorizedAccess”) == 0) {
simulateUnauthorizedAccess();
delete msg;
} else if (strcmp(msg->getName(), “commandInjection”) == 0) {
simulateCommandInjection();
delete msg;
} else {
TcpAppBase::handleMessageWhenUp(msg);
}
}
void SCADAThreatSimulation::simulateUnauthorizedAccess()
{
EV << “Simulating unauthorized access attempt…” << endl;
sendRequest(“GET /admin HTTP/1.1\r\nHost: scadaServer\r\n\r\n”);
}
void SCADAThreatSimulation::simulateCommandInjection()
{
EV << “Simulating command injection attack on PLC…” << endl;
sendRequest(“ControlCommand: ShutdownSystem\r\n”);
}
- Run the Simulation
In OMNeT++, compile and run the simulation. The SCADA firewall and IDS will observe the network traffic, log security events, and detect anomalies. We can observe how the system responds to the simulated security threats.
- Analyse the Results
Verify the OMNeT++ simulation log to view the security events detected by the SCADAFirewall and SCADAIDS modules. Watch for logs associated to command injection attacks and unauthorized access attempts, and assess the efficiency of the security mechanisms in detecting and mitigating these threats.
- Extend the SCADA Security Features
We can extend this simple SCADA security setup by:
- Implementing advanced detection algorithms: It is used to machine learning or signature-based detection for further sophisticated threat detection.
- Simulating more complex attack scenarios: Contain other general SCADA attacks such as DDoS, or insider threats, MITM (Man-In-The-Middle) attacks.
- Automating response mechanisms: Automatically block malicious IPs, separate compromised devices, or alert operators when a security event is identified.
- Integrating with external security systems: Mimic connections to SIEM (Security Information and Event Management) systems or incorporate with incident response platforms.
This page had given more comprehensive informations about the procedure on how to execute and setup the SCADA Network Security in OMNeT++. We will provide more valuable details concerning this topic in various tools. omnet-manual.com provides great tips for simulating SCADA Network Security using the OMNeT++ tool. If you need quick help understanding your network performance, feel free to contact the omnet-manual.com team.