SAGE/Python functions useful for studying S-boxes and Boolean functions such as computing the DDT, computing the Walsh spectrum, affine equivalence testing... Some of them are implemented in C++ and/or in parallel to improve their performances.
WARNING there are some issues with the latest versions of SAGE pertaining to finite fields arithmetic (methods changed names). We are working on it, bear with us for a bit!
Most functions in sboxU only depend on a recent version of SAGE (it was tested with
version 9.0). Some use openmp for multithreading, and you may need to install it in order to successfully compile.
UPDATE (v1.2): fftw is no longer required. It was replaced with pocketfft, which is contained entirely within pocketfft_hdronly.h.
Installing openmp can be done with:
sudo apt-get install libomp-dev
or, on macOS:
brew install libomp
To use this module, use the following command:
sage --pip install git+https://github.com/lpp-crypto/sboxU
This compiles the C++ part of sboxU and installs the full sboxU module
in your SAGE's python environment. You can then import sboxU like
any other python module.
To create a development shell that contains SAGE with sboxU installed, use the following command:
nix develop github:lpp-crypto/sboxU
The nix package and development shell are currently only implemented for x86_64-linux systems.
As an example of the functions provided by sboxU, you can download and run the SAGE script example.py.
There sboxU generates random permutations and tests their affine
equivalence.
On a unix based system (e.g. Linux or macOS), use the following commands:
wget https://raw.githubusercontent.com/lpp-crypto/sboxU/refs/heads/master/example.py
sage example.py
To write your own script using sboxU, this file should contain from sboxU import *.
You can also import sboxU in a sage notebook session.
undefined symbol: _Py_ZeroStructIf you get such an error, there are probably mismatches between the python versions used. This typically happens if you have 2 versions of SAGE installed, used the most recent one to compilesboxU, but then use an older one in your scripts.
When operating over fields of odd characteristic, we use the [pocketfft] (https://gitlab.mpcdf.mpg.de/mtr/pocketfft) library (pocketfft_hdronly.h was taken from the cpp branch) and we would like to thank their authors.