Groth16 Implementation in Rust

An implementation of the Groth16 zk-SNARK protocol in Rust.
This project follows the algorithm end-to-end: from R1CS constraints, to QAP construction, to trusted setup, proof generation, and verification.

The implementation is intentionally explicit and low-level. Nothing is hidden behind DSLs or circuit compilers. If you want to understand how Groth16 actually works under the hood, this code is meant to be read.

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Cryptographic Stack

This implementation uses the following arkworks libraries:

• ark-ff — finite field arithmetic
• ark-ec — elliptic curve and pairing abstractions
• arkworks curve libraries

All group operations, pairings, and field arithmetic are handled explicitly through these libraries.

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Curves Supported

This implementation is curve-agnostic, meaning it is not limited to just one curve. You can use any of the following curves to verify your proof:

• BN254
• BLS12-381
• BLS12-377
• BW-767

You can also modify Cargo.toml and use any other curve of your choice (as long as they are pairing-friendly).

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Features

• Proper Groth16 implementation

  • Produces a valid proof for a correct witness
  • Rejects proofs generated from an invalid witness

• Full pipeline

  • R1CS (matrix representation of constraints)
  • QAP construction
  • Polynomial evaluations
  • Encoding into elliptic curve group elements
  • Proof generation and verification

• Proper trusted setup

  • Includes toxic waste parameters
  • Uses structured reference strings derived from a secret τ

• Soundness and zero-knowledge

  • α, β: prevent forged proofs
  • γ, δ: enforce public input consistency
  • r, s: proof randomization for true zero-knowledge

• Flexible R1CS

  • Manually define any valid R1CS matrix of arbitrary size
  • Control:
    • N → number of rows
    • M → number of columns
    • L → number of public inputs

• Minimal interface

  • Define Curve to be used in types.rs
  • Define constraints in r1cs.rs
  • Define witness values in witness.rs
  • Run with cargo run

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