coSNARKs

coCircom and coNoir are tools for building coSNARKs, a new technology that enables multiple distrusting parties to collaboratively compute a zero-knowledge proof (ZKP). They leverage the existing domain-specific languages circom and Noir to define arithmetic circuits. With coCircom, all existing circom circuits can be promoted to coSNARKs without any modification to the original circuit.

Additionally, coCircom is fully compatible with the Groth16 and Plonk backends of snarkjs, the native proving systems for circom. Proofs generated with coCircom can be verified using snarkjs, and vice versa. The same applies to coNoir, generated proofs can be verified with Barretenberg, and vice versa.

The project is built with pure Rust and consists of multiple libraries:

• coCircom:
• co-circom: The main library that exposes the functionality of coCircom.
• circom-mpc-vm: A MPC-VM that executes the circom file in a distributed manner (building the extended witness).
• circom-mpc-compiler: A compiler that generates the MPC-VM code from the circom file.
• circom-types: A library for serialization and deserialization of snarkjs artifacts, such as ZKeys and R1CS files.
• co-groth16: A library for verifying and proving a Groth16 coSNARK, verifiable by snarkjs.
• co-plonk: A library for verifying and proving a Plonk coSNARK, verifiable by snarkjs.

• co-circom-types: A library for the shared types and code of co-plonk and co-groth16.

• coNoir:

• co-noir: The main library that exposes the functionality of coNoir.
• co-acvm: A MPC version of Noir's ACVM that executes ACIR.
• co-brillig: A MPC version of Noir's Brillig VM that executes unconstrained functions.
• co-builder: A library that transforms the generated shared witness into a shared proving key.
• co-ultrahonk: A MPC version of Aztec's UltraHonk prover, compatible with Barretenberg.
• ultrahonk: A a Rust rewrite of Aztec's UltraHonk prover, compatible with Barretenberg.

The following libraries are agnostic to coCircom/coNoir and will be used in the future for other coSNARKs:

• mpc-core: Implementation of MPC protocols.
• mpc-net: Network library for MPC protocols.

The co-circom and co-noir binaries are CLI tools that use these libraries to build a coSNARK. Both libraries also expose all functionality used by the binaries, so that you can integrate them into you projects. Checkout the coCircom examples and coNoir examples to see more.

Installation

Prerequisites

1. Install Rust. You can find the instructions here.
2. Install the circom ecosystem. You can find the instructions here.

Install from Source

• coCircom

cargo install --git https://github.com/TaceoLabs/co-snarks --branch main co-circom

• coNoir

cargo install --git https://github.com/TaceoLabs/co-snarks --branch main co-noir

Download Binary from Release

1. You can find the latest release here.

2. Download the binary for your operating system.

3. Extract the binary from the archive

tar xf co-circom-YOUR_ARCHITECTURE.tar.gz

1. Make the binary executable (if necessary):

chmod +x co-circom

Documentation

You can find the documentation of coCircom here.

Contributing

If you would like to contribute to the project, please refer to the contribution page.

License

This project is licensed under either the MIT License or the Apache, at your choice.

SPDX-License-Identifier: Apache-2.0 OR MIT

Select sub-libraries within this project have different licenses, reflecting their dependencies on circom.

• co-circom: Licensed under GPL-3.0 SPDX-License-Identifier: GPL-3.0-only.
• circom-mpc-compiler: Licensed under GPL-3.0 SPDX-License-Identifier: GPL-3.0-only.

Disclaimer

This software is experimental and un-audited, provided on an "as is" and "as available" basis. We do not provide any warranties, express or implied, including but not limited to warranties of merchantability or fitness for a particular purpose. We will not be liable for any losses, damages, or issues arising from the use of this software, whether direct or indirect.

Users are encouraged to exercise caution and conduct their own independent assessments and testing. By using this software, you acknowledge and accept the risks associated with its experimental nature and agree that the developers and contributors are not responsible for any consequences resulting from its use.