PX4 Log Encryption Tools

Tools for generating encryption keys, building PX4 firmware with encrypted logs, downloading logs, and decrypting them.

For more information see: https://docs.px4.io/main/en/dev_log/log_encryption.html

Usage

Get the board file: In order to use these tools you need to create an encrypted_logs target in your target board directory. For example:
```
encrypted_logs.px4board
```
Using make menuconfig you should enable these settings: Blake2s hash algorithm, entropy pool and strong random number generator and select use interrupts to feed timing randomness to the entropy pool. Once you have generated the keys make sure you add them to the boardconfig.
```
make <your_board_name>_encrypted_logs menuconfig
```
Generate Keys:
```
cd PX4-Autopilot/Tools/log_encryption
python3 generate_keys.py
```
Make sure you have the right key in your board file CONFIG_PUBLIC_KEY1="../../../keys/public/public_key.pub"

Build Firmware:

cd PX4-Autopilot

AND

make <your_board_name>_encrypted_logs

FOR INSTANCE
make_ark_fpv_encrypted_logs

Upload the custom firmware on your flight controller and record some logs

Download Logs:

cd PX4-Autopilot/Tools/log_encryption

python3 download_logs.py /dev/ttyACM0 --baudrate 57600

OR

python3 download_logs.py udp:0.0.0.0:14550

Addresses might need to be adjusted

Decrypt Logs: The easiest way to run this is to have your private key and encrypted logs in the following folders respectively:

PX4-Autopilot/keys/private
PX4-Autopilot/logs/encrypted

Then run:

cd PX4-Autopilot/Tools/log_encryption

AND
# Uses default key + default folder
python3 decrypt_logs.py

OR
# Use --help to get all the options
python3 decrypt_logs.py --help

Your decrypted logs can be found in:

PX4-Autopilot/logs/decrypted

Otherwise

Directory Structure

keys/: Encryption keys.
logs/encrypted/: Downloaded encrypted logs.
logs/decrypted/: Decrypted logs.