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::{
 21        nova::{
 22            decider_eth::{prepare_calldata, Decider as DeciderEth},
 23            Nova, PreprocessorParam,
 24        },
 25        traits::CommittedInstanceOps,
 26    },
 27    frontend::FCircuit,
 28    transcript::poseidon::poseidon_canonical_config,
 29    Decider, FoldingScheme,
 30};
 31use frontends::noname::NonameFCircuit;
 32use std::time::Instant;
 33
 34use solidity_verifiers::{
 35    evm::{compile_solidity, Evm},
 36    utils::get_function_selector_for_nova_cyclefold_verifier,
 37    verifiers::nova_cyclefold::get_decider_template_for_cyclefold_decider,
 38    NovaCycleFoldVerifierKey,
 39};
 40
 41fn main() {
 42    const NONAME_CIRCUIT_EXTERNAL_INPUTS: &str =
 43        "fn main(pub ivc_inputs: [Field; 2], external_inputs: [Field; 2]) -> [Field; 2] {
 44    let xx = external_inputs[0] + ivc_inputs[0];
 45    let yy = external_inputs[1] * ivc_inputs[1];
 46    assert_eq(yy, xx);
 47    return [xx, yy];
 48}";
 49
 50    // set the initial state
 51    let z_0 = vec![Fr::from(2), Fr::from(5)];
 52
 53    // set the external inputs to be used at each step of the IVC, it has length of 10 since this
 54    // is the number of steps that we will do
 55    let external_inputs = vec![
 56        vec![Fr::from(8u32), Fr::from(2u32)],
 57        vec![Fr::from(40), Fr::from(5)],
 58    ];
 59
 60    // initialize the noname circuit
 61    let f_circuit_params = (NONAME_CIRCUIT_EXTERNAL_INPUTS.to_owned(), 2, 2);
 62    let f_circuit = NonameFCircuit::<Fr, R1csBn254Field>::new(f_circuit_params).unwrap();
 63
 64    pub type N = Nova<
 65        G1,
 66        GVar,
 67        G2,
 68        GVar2,
 69        NonameFCircuit<Fr, R1csBn254Field>,
 70        KZG<'static, Bn254>,
 71        Pedersen<G2>,
 72    >;
 73    pub type D = DeciderEth<
 74        G1,
 75        GVar,
 76        G2,
 77        GVar2,
 78        NonameFCircuit<Fr, R1csBn254Field>,
 79        KZG<'static, Bn254>,
 80        Pedersen<G2>,
 81        Groth16<Bn254>,
 82        N,
 83    >;
 84
 85    let poseidon_config = poseidon_canonical_config::<Fr>();
 86    let mut rng = rand::rngs::OsRng;
 87
 88    // prepare the Nova prover & verifier params
 89    let nova_preprocess_params = PreprocessorParam::new(poseidon_config, f_circuit.clone());
 90    let nova_params = N::preprocess(&mut rng, &nova_preprocess_params).unwrap();
 91
 92    // initialize the folding scheme engine, in our case we use Nova
 93    let mut nova = N::init(&nova_params, f_circuit.clone(), z_0).unwrap();
 94
 95    // prepare the Decider prover & verifier params
 96    let (decider_pp, decider_vp) =
 97        D::preprocess(&mut rng, nova_params.clone(), nova.clone()).unwrap();
 98
 99    // run n steps of the folding iteration
100    for (i, external_inputs_at_step) in external_inputs.iter().enumerate() {
101        let start = Instant::now();
102        nova.prove_step(rng, external_inputs_at_step.clone(), None)
103            .unwrap();
104        println!("Nova::prove_step {}: {:?}", i, start.elapsed());
105    }
106
107    // verify the last IVC proof
108    let ivc_proof = nova.ivc_proof();
109    N::verify(
110        nova_params.1, // Nova's verifier params
111        ivc_proof,
112    )
113    .unwrap();
114
115    let start = Instant::now();
116    let proof = D::prove(rng, decider_pp, nova.clone()).unwrap();
117    println!("generated Decider proof: {:?}", start.elapsed());
118
119    let verified = D::verify(
120        decider_vp.clone(),
121        nova.i,
122        nova.z_0.clone(),
123        nova.z_i.clone(),
124        &nova.U_i.get_commitments(),
125        &nova.u_i.get_commitments(),
126        &proof,
127    )
128    .unwrap();
129    assert!(verified);
130    println!("Decider proof verification: {}", verified);
131
132    // Now, let's generate the Solidity code that verifies this Decider final proof
133    let function_selector =
134        get_function_selector_for_nova_cyclefold_verifier(nova.z_0.len() * 2 + 1);
135
136    let calldata: Vec<u8> = prepare_calldata(
137        function_selector,
138        nova.i,
139        nova.z_0,
140        nova.z_i,
141        &nova.U_i,
142        &nova.u_i,
143        proof,
144    )
145    .unwrap();
146
147    // prepare the setup params for the solidity verifier
148    let nova_cyclefold_vk = NovaCycleFoldVerifierKey::from((decider_vp, f_circuit.state_len()));
149
150    // generate the solidity code
151    let decider_solidity_code = get_decider_template_for_cyclefold_decider(nova_cyclefold_vk);
152
153    // verify the proof against the solidity code in the EVM
154    let nova_cyclefold_verifier_bytecode = compile_solidity(&decider_solidity_code, "NovaDecider");
155    let mut evm = Evm::default();
156    let verifier_address = evm.create(nova_cyclefold_verifier_bytecode);
157    let (_, output) = evm.call(verifier_address, calldata.clone());
158    assert_eq!(*output.last().unwrap(), 1);
159
160    // save smart contract and the calldata
161    println!("storing nova-verifier.sol and the calldata into files");
162    use std::fs;
163    fs::write(
164        "./examples/nova-verifier.sol",
165        decider_solidity_code.clone(),
166    )
167    .unwrap();
168    fs::write("./examples/solidity-calldata.calldata", calldata.clone()).unwrap();
169    let s = solidity_verifiers::utils::get_formatted_calldata(calldata.clone());
170    fs::write("./examples/solidity-calldata.inputs", s.join(",\n")).expect("");
171}