MKCKKS_Go2Py Python Wrapper

Python wrapper for Golang-based Homomorphic Encryption library that performs Multi-key CKKS.

Introduction

This library implements a Multi-key CKKS (MKCKKS) library for Multi-key Homomorphic Encryption (MK-HE) in Python.

It provides a wrapper for the Golang-based MKCKKS library MKHE-KKLSS (https://github.com/SNUCP/MKHE-KKLSS), which is from the paper "Asymptotically Faster Multi-Key Homomorphic Encryption from Homomorphic Gadget Decomposition" (https://eprint.iacr.org/2022/347), published in ACM CCS'23.

This library will build a C-style dynamic link library (dll) from the Golang code using cgo, allowing calling go functions from Python programs using ctypes.

We implement this library to perform MK-HE in the context of Federated Learning (FL), currently this library supports:

• Public & private key generation
• Encoding & encryption on a list of double data using public key
• Homomorphic addition between 2 ciphertexts
• Homomorphic multiplication between a ciphertext and a constant value
• Partial decryption
• Aggregating the partial decryption results and decoding

Note: Our implementation considers encrypting double data type, you will need to make your own changes to encrypt compelx data type.

Prerequisites

• Go and cgo
• Python and ctypes

How to Use

The C-style dll needs to be generated for different platforms, to generate your own dll, open a terminal at the root directory of this project and enter:

go build -o mkckks.so -buildmode=c-shared export.go

This generates a dll named mkckks.so (for Linux & macOS, change into mkckks.dll for Windows) from the export.go file. Please refer to the jupyter notebook tutorials.ipynb for details of how to import this dll in Python and perform HE operations.

Acknowledgement

MKHE-KKLSS: https://github.com/SNUCP/MKHE-KKLSS

Python Wrapper for Lattigo: https://github.com/chandra-gummaluru/FL-Development/tree/MPHE

Instructions for the Golang Code Base:

Source: MKHE-KKLSS

This repository provides an implementation of the Multi-key Homomorphic Encryption scheme in (https://eprint.iacr.org/2022/347). This project was supported by Samsung Research, Samsung Electronics Co., Ltd.

HOW TO INSTALL

use "go mod vendor"

HOW TO RUN UNITTEST

1. go to target folder (e.g for mkckks "cd mkckks")
2. run go test command "go test -args -n=x" (x is the number of parties e.g for 2 parites set x to 2)

HOW TO RUN BENCHMARK

1. go to target folder (e.g for mkckks "cd mkckks")
2. run go benchmark command "go test -bench=. -benchtime=10x -timeout=0 -args -n=4" (This runs 10 repetition of benchmark for the 4 party case)