This document lists required steps to start build your own OpenSK.
OpenSK supports different ways to flash your board:
- Segger J-Link (default method).
- OpenOCD.
- pyOCD.
- nrfutil for the USB dongle boards that support it, which allows you to directly flash a working board over USB without additional hardware.
In order to compile and flash a working OpenSK firmware, you will need the following:
- rustup (can be installed with Rustup)
- python3 and pip (can be installed with the
python3-pip
package on Debian) - the OpenSSL command line tool (can be installed and configured with the
libssl-dev
andpkg-config
packages on Debian) nrfutil
(can be installed usingpip3 install nrfutil
) if you want to flash a device with DFUuuid-runtime
if you are missing theuuidgen
command.
The proprietary software to use the default programmer can be found on the Segger website. Please follow their instructions to appropriate binaries for your system.
The scripts provided in this project have been tested under Linux and OS X. We haven't tested them on Windows and other platforms.
If you are switching branches or used an old version of OpenSK before, we have tools to help you migrate to our develop branch. You find more information on how to update your setup or reset your storage in its install instructions.
To clone and setup the repository for the stable branch, run the following commands:
git clone https://github.com/google/OpenSK.git
cd OpenSK
./setup.sh
The setup script performs the following steps:
-
Make sure that the git submodules are checked out.
-
Apply our patches that haven't yet been merged upstream to both Tock and libtock-rs.
-
Generate crypto material, see Customization for details.
-
Install the correct Rust toolchain for ARM devices.
-
Install tockloader.
Additionally on Linux, you need to install a udev
rule file to allow non-root
users to interact with OpenSK devices. To install it, execute:
sudo cp rules.d/55-opensk.rules /etc/udev/rules.d/
sudo udevadm control --reload
Then, you need and replug the device for the rule to trigger.
Last, if you want to use U2F or attestation, configure the certificate. If your client does not support FIDO2 yet, this step is mandatory for your OpenSK to work. OpenSK is incompatible with some browsers without a certificate. Please read the certificate section in Customization for understand privacy tradeoffs.
./tools/configure.py \
--certificate=crypto_data/opensk_cert.pem \
--private-key=crypto_data/opensk.key
From here on, please follow the instructions for your hardware:
We recommend that you flash your development board with JTAG and dongles with DFU, as described in the board documentation linked above. However, we support other programmers:
- OpenOCD:
./deploy.py --board=nrf52840_dongle --opensk --programmer=openocd
- pyOCD:
./deploy.py --board=nrf52840_dongle --opensk --programmer=pyocd
- Custom:
./deploy.py --board=nrf52840_dongle --opensk --programmer=none
. In this case, an IntelHex file will be created and how to program a board is left to the user.
If your board is already flashed with Tock OS, you may skip installing it:
./deploy.py --board=nrf52840dk --opensk --no-tockos
For more options, we invite you to read the help of our deploy.py
script by
running ./deploy.py --help
.