What is it?

CANalyze is an open source, native CAN interface for Linux. It enables you to monitor and transmit CAN frames using existing Linux tools. It's designed for hacking your car's CAN bus via the OBD-II port and optimized for performance by using a native binary protocol as opposed to an ASCII based serial protocol (slcan). I wrote a quick-start guide to hacking cars.

CANalyze connects to a computer via a USB 2.0 type A male to type B male cable and to the car's OBD-II port via a CiA DS102-2 or standard OBD-II to DB9 cable. These cables are not included. You can set which cable you want to use, as well as a 120 ohm termination resistor via DIP switches.

Why did you make it?

When I started hacking cars, I looked for ways to connect to my car's CAN bus. I often came across ELM327 based devices. While these are good for certain tasks, they are terrible for reversing the CAN bus because they are way too slow. They aren't built for reverse engineering since they use an ASCII based serial protocol which offers lesser performance than native binary protocols. I would constantly get buffer overflows which pretty much rendered them useless for monitoring CAN traffic. Professional devices cost a couple hundred dollars and sometimes require you to also purchase the software, so that wasn't a good option.

Most of the software I used was mediocre at best. ELM327 based devices require a sequence of commands just to monitor or transmit data. Surely this had to be easier... When I stumbled on Linux's can-utils all that changed, the software is great! It uses Linux's native support for CAN (SocketCAN) which makes it very easy to use and offers a lot of functionality. The data is presented in a very clean way and it's super easy to use. Want to send a CAN packet? "cansend can0 123#01020304". Want to dump CAN data? "candump can0".

So then the question became, for which devices does Linux have native support? There are a few but they are generally closed source and/or expensive. So I decided to make CANalyze with the sole focus of offering the best possible integration with existing Linux tools.

What makes it special?

The focus of CANalyze is to offer the best possible integration with existing Linux tools. Since Linux's can-utils is fantastic software, there's no need to reinvent the wheel. All that is needed is good affordable hardware to go with it.