This software allows you to find the key for Motorola/Hytera/Anytone ARC4-40 EP DMR Encryption.

It works with a Raspberry Pi.

Tests in real conditions:

The software works with a Raspberry pi 1/2/3/4/5

The 64-bit arm software works with an Odroid N2/N2+ (with Armbian, Debian or Ubuntu OS)

Time to find a key:

Option 1, 64-bit OS (A fan is mandatory for the processor, otherwise the speed drops):
Raspberry Pi 3B+: 12 days (average) to 24 days (max)
Raspberry Pi 4 : 6.5 days (average) to 13 days (max)
Odroid N2+ : 5 days (average) to 10 days (max)
Raspberry Pi 5 : 3 days (average) to 6 days (max)

The number of days shown depends on the number of keys searched per second.

With a Raspberry Pi 3B+ the program should search for around 500,000 keys per second.
With a Raspberry Pi 4 the program should search for around 1,000,000 keys per second.
With a Raspberry Pi 5 the program should search for around 2,000,000 keys per second.

These speeds are for option 1 on a 64-bit Raspberry Pi OS with a fan.

If you don't have these speeds, then your Raspberry Pi is misconfigured.

Check that you are with option 1 with a 64-bit Raspberry Pi OS (32-bit is slower) and use a new system because if you have a lot of programs installed on your Rapsberry Pi, it may slow down the search.

The mathematical formula for the maximum number of days is as follows: (^ = power)

(2^40/keys per second for your raspberry pi)/86400

example:

Raspberry Pi 5 : (2^40/2000000)/86400=6.3 days

How to start this program:

1-Extract the pdf manual file from the zip file and read it

2-Boot your Raspberry Pi with Raspberry Pi OS desktop version 32-bit or 64-bit

3-Extract the arc4keyfinder 32bit or 64bit program (depending on your version of Pi OS) from the zip file and paste it to the desktop of your raspberry pi

4-Open a terminal console and type this:

cd Desktop

sudo chmod 777 arc4keyfinder

./arc4keyfinder

Want to quickly test your own key with your Motorola radio?

Don't go wrong with the start block and the end block.

You must use the last byte of the key for the block:

If your key is: 11 22 33 44 55

Start Block: 55
End Block: 55