sonobe/examples/full_flow.rs

#![allow(non_snake_case)]
#![allow(non_camel_case_types)]
#![allow(clippy::upper_case_acronyms)]
///
/// This example performs the full flow:
/// - define the circuit to be folded
/// - fold the circuit with Nova+CycleFold's IVC
/// - generate a DeciderEthCircuit final proof
/// - generate the Solidity contract that verifies the proof
/// - verify the proof in the EVM
///
use ark_bn254::{constraints::GVar, Bn254, Fr, G1Projective as G1};
use ark_crypto_primitives::snark::SNARK;
use ark_ff::PrimeField;
use ark_groth16::VerifyingKey as G16VerifierKey;
use ark_groth16::{Groth16, ProvingKey};
use ark_grumpkin::{constraints::GVar as GVar2, Projective as G2};
use ark_poly_commit::kzg10::VerifierKey as KZGVerifierKey;
use ark_r1cs_std::alloc::AllocVar;
use ark_r1cs_std::fields::fp::FpVar;
use ark_relations::r1cs::{ConstraintSystemRef, SynthesisError};
use ark_std::Zero;
use std::marker::PhantomData;
use std::time::Instant;

use folding_schemes::{
    commitment::{
        kzg::{ProverKey as KZGProverKey, KZG},
        pedersen::Pedersen,
        CommitmentScheme,
    },
    folding::nova::{
        decider_eth::{prepare_calldata, Decider as DeciderEth},
        decider_eth_circuit::DeciderEthCircuit,
        get_cs_params_len, Nova, ProverParams,
    },
    frontend::FCircuit,
    transcript::poseidon::poseidon_test_config,
    Decider, Error, FoldingScheme,
};
use solidity_verifiers::{
    evm::{compile_solidity, Evm},
    utils::get_function_selector_for_nova_cyclefold_verifier,
    verifiers::nova_cyclefold::get_decider_template_for_cyclefold_decider,
    NovaCycleFoldVerifierKey,
};

/// Test circuit to be folded
#[derive(Clone, Copy, Debug)]
pub struct CubicFCircuit<F: PrimeField> {
    _f: PhantomData<F>,
}
impl<F: PrimeField> FCircuit<F> for CubicFCircuit<F> {
    type Params = ();
    fn new(_params: Self::Params) -> Self {
        Self { _f: PhantomData }
    }
    fn state_len(&self) -> usize {
        1
    }
    fn step_native(&self, _i: usize, z_i: Vec<F>) -> Result<Vec<F>, Error> {
        Ok(vec![z_i[0] * z_i[0] * z_i[0] + z_i[0] + F::from(5_u32)])
    }
    fn generate_step_constraints(
        &self,
        cs: ConstraintSystemRef<F>,
        _i: usize,
        z_i: Vec<FpVar<F>>,
    ) -> Result<Vec<FpVar<F>>, SynthesisError> {
        let five = FpVar::<F>::new_constant(cs.clone(), F::from(5u32))?;
        let z_i = z_i[0].clone();

        Ok(vec![&z_i * &z_i * &z_i + &z_i + &five])
    }
}

#[allow(clippy::type_complexity)]
fn init_test_prover_params<FC: FCircuit<Fr, Params = ()>>() -> (
    ProverParams<G1, G2, KZG<'static, Bn254>, Pedersen<G2>>,
    KZGVerifierKey<Bn254>,
) {
    let mut rng = ark_std::test_rng();
    let poseidon_config = poseidon_test_config::<Fr>();
    let f_circuit = FC::new(());
    let (cs_len, cf_cs_len) =
        get_cs_params_len::<G1, GVar, G2, GVar2, FC>(&poseidon_config, f_circuit).unwrap();
    let (kzg_pk, kzg_vk): (KZGProverKey<G1>, KZGVerifierKey<Bn254>) =
        KZG::<Bn254>::setup(&mut rng, cs_len).unwrap();
    let (cf_pedersen_params, _) = Pedersen::<G2>::setup(&mut rng, cf_cs_len).unwrap();
    let fs_prover_params = ProverParams::<G1, G2, KZG<Bn254>, Pedersen<G2>> {
        poseidon_config: poseidon_config.clone(),
        cs_params: kzg_pk.clone(),
        cf_cs_params: cf_pedersen_params,
    };
    (fs_prover_params, kzg_vk)
}
/// Initializes Nova parameters and DeciderEth parameters. Only for test purposes.
#[allow(clippy::type_complexity)]
fn init_params<FC: FCircuit<Fr, Params = ()>>() -> (
    ProverParams<G1, G2, KZG<'static, Bn254>, Pedersen<G2>>,
    KZGVerifierKey<Bn254>,
    ProvingKey<Bn254>,
    G16VerifierKey<Bn254>,
) {
    let mut rng = rand::rngs::OsRng;
    let start = Instant::now();
    let (fs_prover_params, kzg_vk) = init_test_prover_params::<FC>();
    println!("generated Nova folding params: {:?}", start.elapsed());
    let f_circuit = FC::new(());

    pub type NOVA<FC> = Nova<G1, GVar, G2, GVar2, FC, KZG<'static, Bn254>, Pedersen<G2>>;
    let z_0 = vec![Fr::zero(); f_circuit.state_len()];
    let nova = NOVA::init(&fs_prover_params, f_circuit, z_0.clone()).unwrap();

    let decider_circuit =
        DeciderEthCircuit::<G1, GVar, G2, GVar2, KZG<Bn254>, Pedersen<G2>>::from_nova::<FC>(
            nova.clone(),
        )
        .unwrap();
    let start = Instant::now();
    let (g16_pk, g16_vk) =
        Groth16::<Bn254>::circuit_specific_setup(decider_circuit.clone(), &mut rng).unwrap();
    println!(
        "generated G16 (Decider circuit) params: {:?}",
        start.elapsed()
    );
    (fs_prover_params, kzg_vk, g16_pk, g16_vk)
}

fn main() {
    let n_steps = 10;
    // set the initial state
    let z_0 = vec![Fr::from(3_u32)];

    let (fs_prover_params, kzg_vk, g16_pk, g16_vk) = init_params::<CubicFCircuit<Fr>>();

    pub type NOVA = Nova<G1, GVar, G2, GVar2, CubicFCircuit<Fr>, KZG<'static, Bn254>, Pedersen<G2>>;
    pub type DECIDERETH_FCircuit = DeciderEth<
        G1,
        GVar,
        G2,
        GVar2,
        CubicFCircuit<Fr>,
        KZG<'static, Bn254>,
        Pedersen<G2>,
        Groth16<Bn254>,
        NOVA,
    >;
    let f_circuit = CubicFCircuit::<Fr>::new(());

    // initialize the folding scheme engine, in our case we use Nova
    let mut nova = NOVA::init(&fs_prover_params, f_circuit, z_0).unwrap();
    // run n steps of the folding iteration
    for i in 0..n_steps {
        let start = Instant::now();
        nova.prove_step().unwrap();
        println!("Nova::prove_step {}: {:?}", i, start.elapsed());
    }

    let rng = rand::rngs::OsRng;
    let start = Instant::now();
    let proof = DECIDERETH_FCircuit::prove(
        (g16_pk, fs_prover_params.cs_params.clone()),
        rng,
        nova.clone(),
    )
    .unwrap();
    println!("generated Decider proof: {:?}", start.elapsed());

    let verified = DECIDERETH_FCircuit::verify(
        (g16_vk.clone(), kzg_vk.clone()),
        nova.i,
        nova.z_0.clone(),
        nova.z_i.clone(),
        &nova.U_i,
        &nova.u_i,
        &proof,
    )
    .unwrap();
    assert!(verified);
    println!("Decider proof verification: {}", verified);

    // Now, let's generate the Solidity code that verifies this Decider final proof
    let function_selector =
        get_function_selector_for_nova_cyclefold_verifier(nova.z_0.len() * 2 + 1);

    let calldata: Vec<u8> = prepare_calldata(
        function_selector,
        nova.i,
        nova.z_0,
        nova.z_i,
        &nova.U_i,
        &nova.u_i,
        proof,
    )
    .unwrap();

    // prepare the setup params for the solidity verifier
    let nova_cyclefold_vk = NovaCycleFoldVerifierKey::from((g16_vk, kzg_vk, f_circuit.state_len()));

    // generate the solidity code
    let decider_solidity_code = get_decider_template_for_cyclefold_decider(nova_cyclefold_vk);

    // verify the proof against the solidity code in the EVM
    let nova_cyclefold_verifier_bytecode = compile_solidity(&decider_solidity_code, "NovaDecider");
    let mut evm = Evm::default();
    let verifier_address = evm.create(nova_cyclefold_verifier_bytecode);
    let (_, output) = evm.call(verifier_address, calldata.clone());
    assert_eq!(*output.last().unwrap(), 1);

    // save smart contract and the calldata
    println!("storing nova-verifier.sol and the calldata into files");
    use std::fs;
    fs::write(
        "./examples/nova-verifier.sol",
        decider_solidity_code.clone(),
    )
    .unwrap();
    fs::write("./examples/solidity-calldata.calldata", calldata.clone()).unwrap();
    let s = solidity_verifiers::utils::get_formatted_calldata(calldata.clone());
    fs::write("./examples/solidity-calldata.inputs", s.join(",\n")).expect("");
}