Fully Homomorphic Encryption (Toy Example)

This project demonstrates a simple, toy implementation of fully homomorphic encryption (FHE) in C++. It supports encryption, decryption, homomorphic addition, multiplication, and simulated bootstrapping (noise reset).

Features

• Toy FHE scheme (not secure for real use)
• Arbitrary integer message support (within modulus limits)
• Homomorphic addition and multiplication
• Bootstrapping (noise reset by decrypting and re-encrypting)
• Large random prime modulus for improved demonstration security

Build

cmake -S . -B build
cmake --build build

Run

./build/fhe_app.exe
./build/fhe_test.exe

Files

• src/fhe.hpp, src/fhe.cpp: FHE implementation.

• src/main.cpp: Example usage

• tests/test.cpp: Sample tests

Note

This code is for educational purposes only. For real FHE, use libraries like Microsoft SEAL or HElib e.t.c.