IPCamp Competition - Signal Simulator

A solution by Szabó Gergely.

Build, test, setup

• Show in the IDE: You need to have Lombok installed.
• Requirements: Java 8+, Maven
• Build: $ mvn clean install
• Test: $ mvn test
• Setup: The compiled jar file is executable. (Thanks to spring-boot) It can also be used as a web archive (.war file).

$ java -Xmx<memory>M -Dspring.profiles.active=<mode> -jar simulator-<version>.jar

Configuration

Config files

Custom config files are available for every profiles.

• src/main/resources/application.properties : Global settings
• src/main/resources/application-<mode>.properties : Settings for the specified mode

Any configuration property can be set using the -D<property.name>= command line argument.

All of the custom properties are documented. See src/main/resources/META-INF/additional-spring-configuration-metadata.json file for more.

NOTE: Slave nodes must be configured with the same input source, protocol JSON and transporter properties as the master to work properly.

Protocol JSON

- (Optional) Array of VehicleTypes
	- VehicleType: class
		- vehicleType: String
		- frames: array of Frame
			- name: String
			- frameID: number
			- period: number
			- signals: array of Signal
				- name: String
				- position: number
				- length: number

• VehicleType, Frame and Signal is located in the hu.gerviba.simulator.model package.
• Numbers are integers (max 8 byte)
• Examples: test/configs/ folder
• Use simulator.config-file property in the properties file or the -Dsimulator.config-file= command line argument to specify the protocol json.

Profiles (Modes)

Profile name	Description
standalone	Simple behaviour.
master	Accepts and discovers slaves. Manages the slave nodes.
slave	Works as a slave node.

How to set profiles?

Edit the application.properties file or use the -Dspring.profiles.active= command line argument.

Input Sources

RandomFlowInputGenerator

Class name: hu.gerviba.simulator.input.RandomFlowInputGenerator

Generates smooth signal data.

The algorithm is as follows:

• Generate random starting values for every signal per vehicle instance.
• Sets the delta values to 0 for every signal per vehicle instance.
• Every time the scheduler runs the update task: The delta value will be randomly modified and added (or subtracted if it's negative) to the value.

Inspired by 2nd derivatives.

RandomInputGenerator

It generates random data using a simple random generator and masks the generated numbers to match the signal length.

LogBasedInputSource

Class name: hu.gerviba.simulator.input.LogBasedInputSource

This is an example of how can it be used for sending recorded data.

Transporters

HTTP Transporter

Class name: hu.gerviba.simulator.transport.HTTPTransporter

Settings are the following:

simulator.http.host=127.0.0.1
simulator.http.port=80
simulator.http.method=POST
simulator.http.action=cloud/
simulator.http.basic-enabled=false
simulator.http.basic-username=username
simulator.http.basic-password=password

Both HTTP and HTTPS are supported.

I wrote a simple PHP script to test the class:

<?php //name: /var/www/html/cloud/index.php
	$data = file_get_contents("php://input");
	foreach (str_split($data) as $part)
		echo ord($part) . " ";
	echo "\n";

MQTT Transporter

Class name: hu.gerviba.simulator.transport.MQTTTransporter

Settings are the following:

simulator.mqtt.host=127.0.0.1
simulator.mqtt.port=1883
simulator.mqtt.keep-alive=60
simulator.mqtt.id=simulator
simulator.mqtt.topic=simulator
simulator.mqtt.username=testu
simulator.mqtt.password=testp

• If you leave the username empty, authentication will be disabled.
• Currently only QoS=0 supported.
• I found mosquitto very useful for testing.
• MQTT documentation

Debugging

There are three debugging transporter:

• DebugTransporter : Prints packets to standard out
• MockTransporter : Can be used for testing
• NullTransporter : Will ignore any data

RestAPI

Master

To enable: use profile master

Method	Path	Arguments	Description
GET	/api/slaves	none	Returns the list of all slaves

Master and Standalone

Method	Path	Arguments	Description
GET	/api/status/server	none	Returns server status. Used in WebUI dashboard.
GET	/api/inputgenerator/start	none	Starts the input generator.
GET	/api/inputgenerator/stop	none	Stops the input generator.
GET	/api/cluster/start	none	Sends start signals to slaves.
GET	/api/cluster/stop	none	Sends stop signals to slaves.

Slave

To enable: use profile slave

Method	Path	Arguments	Description
GET	/api/slave/status	apiKey:String	Results statistic from this node
POST	/api/slave/start	command:CommandDao	Send command to node
POST	/api/slave/stop	none	Send stop signal

WebUI

To enable: use profile standalone or master.
NOTE: Config property simulator.enable-webui must be true.

Dependencies

• JavaScript, JQuery : Client side
• Google fonts, Google material icons : Client side
• Spring MVC, Thymeleaf : Server side

Endpoints

Method	Path	Description
GET	/	Redirection to /webui
GET	/webui/	WebUI dashboard, realtime statistics
GET	/webui/controls	Input generator (ON/OFF)
GET	/webui/settings	Vehicle count
GET	/webui/cluster	List of slave nodes

Form actions

Method	Path	Arguments	Description
POST	/webui/range	name:String, count:Long	Set the count of the selected vehicle
POST	/webui/controls/start	none	InputSource instance - start() method.
POST	/webui/controls/stop	none	InputSource instance - stop() method.
POST	/webui/cluster/start	none	ClusterService instance - start() method.
POST	/webui/cluster/stop	none	ClusterService instance - stop() method.

Security

Known security issues

• Using transporters (HTTPTransporter, MQTTTransporter) without ssl is dangerous.
• The WebUI and a RestAPI (in standalone and master instances) can be used without authentication.
• The slave apiKey can be easily stolen via man-in-the-middle attacks.

Solutions

• Use HTTPS whenever it's possible.
• Block unnecessary port traffic.
• Use VPNs for remote hosts.

Screenshots