Protecting the car's CAN bus from theft - advantages and disadvantages
Content
In almost any modern car, electronic units “communicate” with each other via the digital CAN bus. Motor, steering wheel, brakes and other electronic components can be connected to this module. An attacker can register a key, connect a "starter" (a device for starting the engine without a key), bypass the CAN lock - calmly start the car and drive away. Protecting the car's CAN bus from theft is one of the actions aimed at preserving your property. The blocking of the module does not affect the operation of the vehicle, it is “invisible” (the hijacker is not able to determine the cause of the blocking visually), it can only be removed using a pin code or a key fob.
In almost any modern car, electronic units “communicate” with each other via the digital CAN bus. Motor, steering wheel, brakes and other electronic components can be connected to this module. An attacker can register a key, connect a "starter" (a device for starting the engine without a key), bypass the CAN lock - calmly start the car and drive away. Protecting the car's CAN bus from theft is one of the actions aimed at preserving your property. The blocking of the module does not affect the operation of the vehicle, it is “invisible” (the hijacker is not able to determine the cause of the blocking visually), it can only be removed using a pin code or a key fob.
What is a CAN module
To understand what a CAN bus is and how it provides car theft protection, it is worth studying the principle of the module and its settings. Let's figure out why attackers can't use the vehicle.
The principle of operation of the CAN module
The bus is an interface unit that interacts with the car's security system and allows you to control the vehicle using specified programs. All nodes of the machine obey the established rules transmitted through the firmware.
CAN system device
When an alarm is activated, a corresponding command is sent to the bus. What happens next is written in the software of this module. Information is entered there using the firmware.
Configuring the CAN module
The principles of setting up the module on the machine depend on the installed alarm. Starline needs to interact with the service button, but before that, the programming mode is activated. Information about sound signals is specified in the instructions for the security system.
How to configure module parameters:
- Press the service button to start programming.
- Open the desired section, the selection will be confirmed with a beep.
- Select an option in the same way.
- Wait for the sound informing you that the state of the selected partition can change.
- If one beep sounds, then the parameter is activated, two - it is deactivated.
If the motorist decides to change other parameters, then he will have to repeat step 2 and the next.
How cars are hacked via CAN bus
The first way to hack a car is to attach a "bug" to the vehicle's wiring. The place is not so important, the main thing is to get to it. It can be a headlight, tail lights, turn signals. This is only necessary for powering and transmitting commands to the general network. After that, one or more nodes execute the command specified in the new network element.
Breaking into a car for theft
Another option is external networks. Sometimes even a smartphone is used if the same car multimedia system does not have Internet access. It is enough to communicate with the radio via Bluetooth. The only drawback of this method is the lack of a mobile device in the car when there is no driver in it.
The last option used is flashing the standard alarm unit. This is the most time-consuming method, but the malicious code will definitely be transmitted over the bus to the desired node, and it will execute the command of the hijackers. So it is prescribed to open the doors, start the engine, turn on the headlights. The strings from the software are removed when the attackers complete their work. No expert will find them when checking the car, when it will be sold on the secondary market with fake documents.
Engine blocking via CAN bus
Protecting the CAN bus of a car for insurance against theft is one way to secure your property. But some drivers limit themselves to blocking the power unit, hoping that the hijackers will not reflash the alarm, but simply try to connect to it and send the desired signal.
How to connect an alarm via CAN bus
Protecting the car's CAN bus from theft involves connecting it to an alarm. Instruction:
- Install an alarm and connect it to all nodes.
- Find the orange cable, it is the largest, it detects the CAN bus.
- Attach the protection system adapter to it.
- Install the device so that it is isolated and fixed.
- Set up communication channels with nodes to fully protect the car.
If the motorist does not have sufficient knowledge for this, then it is better to contact a specialized service.
Benefits of signaling with CAN bus
The main "pluses" of installing a bus for signaling:
- Any motorist who has read the instructions from the alarm manufacturer will be able to cope with the installation and programming.
- The nodes communicate with each other so quickly that intruders cannot take possession of the car.
- External interference does not affect the performance of the system.
- Multilevel monitoring and control systems are available. This will protect the signaling from errors during data transmission.
- Efficient operation of the module is ensured by its ability to distribute the speed over all installed channels.
- Big choice. A car enthusiast will be able to choose any security system with a bus and install it on his car. On sale there are auto protection elements even for old domestic cars.
Layout of CAN elements
There are many “pluses” for such an alarm, but the main one is countering hijackers.
Disadvantages of signaling with CAN bus
With all the positive aspects of such security systems, there are also negative ones:
- Data transfer restrictions. The number of nodes and devices in modern cars is only increasing. And all this is connected to the bus, which seriously increases the load on this element. As a result of such an impact, the response time changes significantly.
- Not all data on the bus is useful. Some of them have only one value, which does not increase the security of movable property.
- There is no standardization. Manufacturers produce different products and the complexity of its configuration depends on this.
There are significantly fewer "minuses", which explains the high demand for such systems.
CAN bus protection
Protecting the car's CAN bus from theft involves the installation of diode assemblies. They prevent the effects of electrostatic discharges and voltage surges. With them, overvoltage during the operation of certain processes is also excluded.
CAN bus hack
One of these assemblies is SM24 CANA. Its main purpose is to dissipate repetitive electrostatic discharges, if their level is higher than recorded in the international standard.
Such assemblies are produced by different manufacturers, but the main requirement for them is certification. The reason for this rigor is the ability to connect to the controls of the "box", engine and security systems.
The main advantages of the described protection:
- high-level electrostatic discharge protection - up to 30 kV;
- reduced dynamic resistance - up to 0,7 OM;
- minimized risk of data loss;
- reduced leakage current;
- the possibility of installation even on old domestic cars.
CAN bus protection is not mandatory, but it allows you to exclude third-party influence on the system, which means it increases the safety of movable property. Therefore, its installation is still recommended.
