Official Python wrapper for OpenFHE

Table of Contents

• Running from Docker
• Building from Source
  • Prerequisites
  • Linux Install
    • Installing directly on your system
    • Using Conda environments
• Running Examples
• OpenFHE Python Wrapper Documentation
• Contributing Guide

Running from Docker

Please see Instructions for the Docker setup

Building from Source

Requirements

Before building, make sure you have the following dependencies installed:

• OpenFHE 1.1.3+ by following the instructions in OpenFHE Documentation
• Python 3.6+
• pybind11

We recommend following OpenFHE C++ installation instructions first (which covers Linux, Windows and MacOS) and then getting back to this repo. See notes on installing pybind11 below

Linux

System-level installation

To install OpenFHE-python directly to your system, ensure the dependencies are set up. Then clone the repository, open a terminal in the repo folder and run the following commands:

pip install "pybind11[global]" 
mkdir build
cd build
cmake ..  # Alternatively, cmake .. -DCMAKE_PREFIX_PATH=/path/to/installed/openfhe if you installed OpenFHE elsewhere
make
make install  # You may have to run sudo make install

At this point the .so file has been built. Your exact installation process will depend on your virtual environment. Cmake will automatically find the python installation path, if unwanted, you can specify the python path by adding -DPYTHON_EXECUTABLE_PATH=/path/to/python to the cmake command.

If you see an error saying that one of OpenFHE .so files cannot be found when running a Python example (occurs only for some environments), add the path where the .so files reside to the PYTHONPATH environment variable:

export PYTHONPATH=(/path/to/installed/openfhe):$PYTHONPATH

In some environments (this happens rarely), it may also be necessary to add the OpenFHE libraries path to LD_LIBRARY_PATH.

If OpenFHE is not installed in the default location, then both PYTHONPATH and LD_LIBRARY_PATH must be set before running any Python example.

Conda

Alternatively you can install the library and handle the linking via Conda. Clone the repository, open a terminal in the repo folder and run the following commands:

conda create -n ${ENV_NAME} python=3.{X} anaconda

where ${ENV_NAME} should be replaced with the name of your environment, and {X} should be replaced with your desired python version. For example you might have conda create -n openfhe_python python=3.9 anaconda. Now, you would install pybind11 either via:

pip install "pybind11[global]" or via conda install -c conda-forge pybind11, but for now we recommend using the first method, with pip. Some users have reported issues when using the conda pybind11

Now, you would clone the repository, and run the following commands to install :

mkdir build
cd build
cmake .. # Add in -DCMAKE_PREFIX_PATH=/path/to/installed/openfhe if you installed OpenFHE elsewhere
make
make install  # You may have to run sudo make install

Then, you can develop the library to link

cd ..
mkdir lib
mv *.so lib
conda develop lib

which creates a lib folder, moves the built .so file into that lib folder, and tells conda where to look for external libraries.

Note You may wish to copy the .so file to any projects of your own, or add it to your system path to source from.

Running Tests

Run tests with pytest, which may be called pytest-3 on your system. See the testing readme for more information.

pytest [--run-long]

Code Examples

To get familiar with the OpenFHE Python API, check out the examples:

• FHE for arithmetic over integers (BFV):
  • Simple Code Example
• FHE for arithmetic over integers (BGV):
  • Simple Code Example
• FHE for arithmetic over real numbers (CKKS):
  • Simple Code Example
  • Advanced Code Example
  • Advanced Code Example for High-Precision CKKS
  • Arbitrary Smooth Function Evaluation
  • Simple CKKS Bootstrapping Example
  • Advanced CKKS Bootstrapping Example
  • Double-Precision (Iterative) Bootstrapping Example
• FHE for Boolean circuits and larger plaintext spaces (FHEW/TFHE):
  • Simple Code Example with Symmetric Encryption
  • Truth Table Example
• Scheme Switching:
  • Examples with Scheme Switching between CKKS and FHEW/TFHE
• Threshold FHE:
  • Code Example for BGV, BFV, and CKKS
  • Simple Interactive Bootstrapping Example
  • Interactive Bootstrapping after Chebyshev Approximation
  • Code Example for BFV with 5 parties

OpenFHE Python Wrapper Documentation

OpenFHE Python Wrapper API Reference

Contributing Guide

OpenFHE Development - Contributing Guide