hhego is a monorepo for all Go-based tools used as part of the HHE (Hybrid Homomorphic Encryption) Proof of Concept.

• bfv: lattigo wrapper, designed to create hybrid homomorphic encryption schemes.
• pasta: contains PASTA symmetric cipher.
• js: A script for generating votes in the fhBallot project.
• jni: Java bindings to integrate it with rskj.
• workspace: a place for small tests.

The goal of hhego is to integrate these components with rskj, enabling support for hybrid homomorphic encryption on Rootstock.

The JNI component enables the use of bfv in Java applications, in this PoC we use it to integrate it with rskj and use it as a precompiled contract.

To build this library, use the following command:

make macos

The output should be libbfv_jni.dylib, a dynamic library for mac.

There's also a bash script that builds and copies the output to rskj.

./build_jni_mac.sh

The JS component includes a Go script designed to generate encrypted votes for the fhBallot project. To execute this script, run:

go run votes.go

This script produces a JSON output with the following structure:

{
    "votes": [[1, 0, 0, 0], [0, 1, 0, 0]], // Generated votes
    "votesPasta": [[30447, 62405, 62714, 38763], [30446, 62406, 62714, 38763]], // Encrypted votes using PASTA
    "pastaSK": [1, 1, 1, 1, 1], // BFV-encrypted PASTA secret key
	"rk": [1, 1, 1, 1, 1], // Relinearization key (for converting PASTA votes to BFV votes)
	"bfvSK": [1, 1, 1, 1, 1] // BFV secret key (used for encrypting PASTA SK)
}

There's also a bash script that builds and copies the output to rskj.

./generate_votes.sh