KZG Commitment Library

This repository contains a Rust implementation of KZG Commitments, a cryptographic primitive used for polynomial commitments. The library provides functionality to generate, commit, and verify polynomial commitments.

Blog post on implementing KZG commitment scheme You can find the python version of this code here

Features

• Vector to Polynomial: Convert a vector of elements to polynomial form.
• Polynomial Commitment: Commit to a polynomial
• Proof Generation: Generate a proof for a given set of points from the vector.
• Proof Verification: Verify the correctness of the proofs generated.

Installation

To use this library, add the following to your Cargo.toml

kzg_commitment = "0.1.0"

Usage

Here is a basic example of how to use the library:

use kzg_commitment::KZGCommitment;
use ark_bls12_381::{Fr as F};

fn main() {
    let kzg = KZGCommitment::new(50);
    let vector = vec![F::from(120), F::from(-15), F::from(60), F::from(80)];
    let polynomial = KZGCommitment::vector_to_polynomial(&vector);
    let commitment = kzg.commit_polynomial(&polynomial);
    let points = vec![(F::from(0), F::from(120)), (F::from(1), F::from(-15))];
    let proof = kzg.generate_proof(&polynomial, &random_points).unwrap();
    let verification = kzg.verify_proof(&commitment, &random_points, &proof);

    assert!(verification, "Verification failed");
}

Testing

To run the tests, use the following command:

cargo test

Example Tests

• test_vec_to_poly: Tests the conversion of a vector to a polynomial and evaluates it at random points.
• test_verify_proof_valid: Tests the generation and verification of a valid proof.
• test_invalid_proof_generation: Tests the generation of an invalid proof and ensures the correct error is returned.
• test_invalid_proof_verification: Tests the verification of an invalid proof and ensures the correct error is returned.

TODO

• Use BigInt for vectors instead of i32
• Add support for precomputed powers_of_tau (trusted_setup)
• Add more tests for invalid proof verification
• Add benchmarks

Contributing

Contributions are welcome! Please open an issue or submit a pull request.

License

This project is licensed under the MIT License. See the LICENSE file for details.

Acknowledgements

KZG Commitments - More information about KZG Commitments.

This project was inspired by Dankrad Feist's blog post on KZG Commitments.