A basic random number generator that generates numbers from the onboard DAC of the Raspberry Pi Pico. The project used the Raspberry Pi Pico USB dev_lowlevel as a starting point. The RNG is not meant to be FIPS 140-2 compliant by a long shot. This is not meant to by used in a production system as a TRNG. Maybe one day the next gen Pico's will include an onboard crypto module.

Project Goals

Raspberry Pi Pico firmware generates random numbers as a USB Endpoint
Linux Kernel Module (aka driver) provides random numbers to the Kernel
Driver can transmit random numbers on demand to the system and/or user processes via a character device

Prerequisites

Raspberry Pi Pico development environment. See Raspberry Pi Pico Getting Started Documentation
Linux Kernel development headers

Building

The entire project uses CMake to keep with Rasberry Pi Pico's development environment and project setup instructions.

# Create build directory
mkdir build

# Change to the build directory
cd build

# Run cmake
cmake ..

# Run make
make

Install

# Assumes CWD is 'build/'
# debug will enable debug log level
# timeout will set the usb endpoint timeout. Currently defaults to 100 msecs
sudo insmod driver/pico_rng.ko [debug=1] [timeout=<msec timeout>]

Testing

You can test Pico RNG firmware with the pico_rng_test.py script.

# Running with --performance will measure the devices' KB/s.
# if the kernel module is inserted, then the test tool will use /dev/pico_rng otherwise python's libusb implementation will be used.
sudo firmware/pico_rng_test.py [--performance]

Remove

sudo rmmod pico_rng

License

This project is licensed under the MIT License - see the LICENSE.md file for details

References

https://github.com/raspberrypi/pico-examples/tree/master/usb/device/dev_lowlevel