1#![allow(non_snake_case)]
  2#![allow(non_camel_case_types)]
  3#![allow(clippy::upper_case_acronyms)]
  4///
  5/// This example performs the full flow:
  6/// - define the circuit to be folded
  7/// - fold the circuit with Nova+CycleFold's IVC
  8/// - generate a DeciderEthCircuit final proof
  9/// - generate the Solidity contract that verifies the proof
 10/// - verify the proof in the EVM
 11///
 12use ark_bn254::{constraints::GVar, Bn254, Fr, G1Projective as G1};
 13use noname::backends::r1cs::R1csBn254Field;
 14
 15use ark_groth16::Groth16;
 16use ark_grumpkin::{constraints::GVar as GVar2, Projective as G2};
 17
 18use folding_schemes::{
 19    commitment::{kzg::KZG, pedersen::Pedersen},
 20    folding::nova::{
 21        decider_eth::{prepare_calldata, Decider as DeciderEth},
 22        Nova, PreprocessorParam,
 23    },
 24    frontend::{noname::NonameFCircuit, FCircuit},
 25    transcript::poseidon::poseidon_canonical_config,
 26    Decider, FoldingScheme,
 27};
 28use std::time::Instant;
 29
 30use solidity_verifiers::{
 31    evm::{compile_solidity, Evm},
 32    utils::get_function_selector_for_nova_cyclefold_verifier,
 33    verifiers::nova_cyclefold::get_decider_template_for_cyclefold_decider,
 34    NovaCycleFoldVerifierKey,
 35};
 36
 37fn main() {
 38    const NONAME_CIRCUIT_EXTERNAL_INPUTS: &str =
 39        "fn main(pub ivc_inputs: [Field; 2], external_inputs: [Field; 2]) -> [Field; 2] {
 40    let xx = external_inputs[0] + ivc_inputs[0];
 41    let yy = external_inputs[1] * ivc_inputs[1];
 42    assert_eq(yy, xx);
 43    return [xx, yy];
 44}";
 45
 46    // set the initial state
 47    let z_0 = vec![Fr::from(2), Fr::from(5)];
 48
 49    // set the external inputs to be used at each step of the IVC, it has length of 10 since this
 50    // is the number of steps that we will do
 51    let external_inputs = vec![
 52        vec![Fr::from(8u32), Fr::from(2u32)],
 53        vec![Fr::from(40), Fr::from(5)],
 54    ];
 55
 56    // initialize the noname circuit
 57    let f_circuit_params = (NONAME_CIRCUIT_EXTERNAL_INPUTS.to_owned(), 2, 2);
 58    let f_circuit = NonameFCircuit::<Fr, R1csBn254Field>::new(f_circuit_params).unwrap();
 59
 60    pub type N = Nova<
 61        G1,
 62        GVar,
 63        G2,
 64        GVar2,
 65        NonameFCircuit<Fr, R1csBn254Field>,
 66        KZG<'static, Bn254>,
 67        Pedersen<G2>,
 68    >;
 69    pub type D = DeciderEth<
 70        G1,
 71        GVar,
 72        G2,
 73        GVar2,
 74        NonameFCircuit<Fr, R1csBn254Field>,
 75        KZG<'static, Bn254>,
 76        Pedersen<G2>,
 77        Groth16<Bn254>,
 78        N,
 79    >;
 80
 81    let poseidon_config = poseidon_canonical_config::<Fr>();
 82    let mut rng = rand::rngs::OsRng;
 83
 84    // prepare the Nova prover & verifier params
 85    let nova_preprocess_params = PreprocessorParam::new(poseidon_config, f_circuit.clone());
 86    let nova_params = N::preprocess(&mut rng, &nova_preprocess_params).unwrap();
 87
 88    // initialize the folding scheme engine, in our case we use Nova
 89    let mut nova = N::init(&nova_params, f_circuit.clone(), z_0).unwrap();
 90
 91    // prepare the Decider prover & verifier params
 92    let (decider_pp, decider_vp) =
 93        D::preprocess(&mut rng, nova_params.clone(), nova.clone()).unwrap();
 94
 95    // run n steps of the folding iteration
 96    for (i, external_inputs_at_step) in external_inputs.iter().enumerate() {
 97        let start = Instant::now();
 98        nova.prove_step(rng, external_inputs_at_step.clone(), None)
 99            .unwrap();
100        println!("Nova::prove_step {}: {:?}", i, start.elapsed());
101    }
102
103    // verify the last IVC proof
104    let ivc_proof = nova.ivc_proof();
105    N::verify(
106        nova_params.1, // Nova's verifier params
107        ivc_proof,
108    )
109    .unwrap();
110
111    let start = Instant::now();
112    let proof = D::prove(rng, decider_pp, nova.clone()).unwrap();
113    println!("generated Decider proof: {:?}", start.elapsed());
114
115    let verified = D::verify(
116        decider_vp.clone(),
117        nova.i,
118        nova.z_0.clone(),
119        nova.z_i.clone(),
120        &nova.U_i,
121        &nova.u_i,
122        &proof,
123    )
124    .unwrap();
125    assert!(verified);
126    println!("Decider proof verification: {}", verified);
127
128    // Now, let's generate the Solidity code that verifies this Decider final proof
129    let function_selector =
130        get_function_selector_for_nova_cyclefold_verifier(nova.z_0.len() * 2 + 1);
131
132    let calldata: Vec<u8> = prepare_calldata(
133        function_selector,
134        nova.i,
135        nova.z_0,
136        nova.z_i,
137        &nova.U_i,
138        &nova.u_i,
139        proof,
140    )
141    .unwrap();
142
143    // prepare the setup params for the solidity verifier
144    let nova_cyclefold_vk = NovaCycleFoldVerifierKey::from((decider_vp, f_circuit.state_len()));
145
146    // generate the solidity code
147    let decider_solidity_code = get_decider_template_for_cyclefold_decider(nova_cyclefold_vk);
148
149    // verify the proof against the solidity code in the EVM
150    let nova_cyclefold_verifier_bytecode = compile_solidity(&decider_solidity_code, "NovaDecider");
151    let mut evm = Evm::default();
152    let verifier_address = evm.create(nova_cyclefold_verifier_bytecode);
153    let (_, output) = evm.call(verifier_address, calldata.clone());
154    assert_eq!(*output.last().unwrap(), 1);
155
156    // save smart contract and the calldata
157    println!("storing nova-verifier.sol and the calldata into files");
158    use std::fs;
159    fs::write(
160        "./examples/nova-verifier.sol",
161        decider_solidity_code.clone(),
162    )
163    .unwrap();
164    fs::write("./examples/solidity-calldata.calldata", calldata.clone()).unwrap();
165    let s = solidity_verifiers::utils::get_formatted_calldata(calldata.clone());
166    fs::write("./examples/solidity-calldata.inputs", s.join(",\n")).expect("");
167}