From 6d8f297f116e1b367d57cc7eb1cf1a5a72eec505 Mon Sep 17 00:00:00 2001 From: Nick Dimitriou <81875532+NiDimi@users.noreply.github.com> Date: Wed, 23 Oct 2024 09:42:34 +0100 Subject: [PATCH] Implemented Mova folding scheme (#161) * Adding Mova Co-Authored-By: Togzhan Barakbayeva <45527668+btogzhan2000@users.noreply.github.com> Co-Authored-By: Ilia Vlasov <5365540+elijahvlasov@users.noreply.github.com> Co-Authored-By: matthew-a-klein <96837318+matthew-a-klein@users.noreply.github.com> * Fix CLI * Updated from main * Solution to stop the CLI from complaining about deadcode PR comment Co-authored-by: arnaucube * Requested changes and update from main * Refactor NIFSTrait & port Mova impl to it * refactor NIFSTrait interface to fit Nova variants (Nova,Mova,Ova) Refactor NIFSTrait interface to fit Nova variants (Nova,Mova,Ova). The relevant change is instead of passing the challenge as input, now it passes the transcript and computes the challenges internally (Nova & Ova still compute a single challenge, but Mova computes multiple while absorbing at different steps). * port Mova impl to the NIFSTrait * remove unnecessary wrappers in the nova/zk.rs * remove Nova NIFS methods that are no longer needed after the refactor * put together the different NIFS implementations (Nova, Mova, Ova) so that they can interchanged at usage. The idea is that Nova and its variants (Ova & Mova) share most of the logic for the circuits & IVC & Deciders, so with the abstracted NIFS interface we will be able to reuse most of the already existing Nova code for having the Mova & Ova circuits, IVC, and Decider. * adapt Nova's DeciderEth prepare_calldata & update examples to it * small update to fix solidity tests --------- Co-authored-by: Togzhan Barakbayeva <45527668+btogzhan2000@users.noreply.github.com> Co-authored-by: Ilia Vlasov <5365540+elijahvlasov@users.noreply.github.com> Co-authored-by: matthew-a-klein <96837318+matthew-a-klein@users.noreply.github.com> Co-authored-by: arnaucube Co-authored-by: arnaucube --- examples/circom_full_flow.rs | 2 + examples/full_flow.rs | 2 + examples/noir_full_flow.rs | 2 + examples/noname_full_flow.rs | 2 + .../src/folding/circuits/cyclefold.rs | 114 ++++- folding-schemes/src/folding/nova/circuits.rs | 17 +- folding-schemes/src/folding/nova/decider.rs | 25 +- .../src/folding/nova/decider_circuits.rs | 20 +- .../src/folding/nova/decider_eth.rs | 47 +- .../src/folding/nova/decider_eth_circuit.rs | 20 +- folding-schemes/src/folding/nova/mod.rs | 82 ++-- folding-schemes/src/folding/nova/nifs/mod.rs | 152 +++++++ folding-schemes/src/folding/nova/nifs/mova.rs | 411 ++++++++++++++++++ .../folding/nova/{nifs.rs => nifs/nova.rs} | 252 ++++------- .../src/folding/nova/{ => nifs}/ova.rs | 95 ++-- .../src/folding/nova/nifs/pointvsline.rs | 282 ++++++++++++ folding-schemes/src/folding/nova/traits.rs | 73 ---- folding-schemes/src/folding/nova/zk.rs | 124 ++---- .../src/verifiers/nova_cyclefold.rs | 2 + 19 files changed, 1239 insertions(+), 485 deletions(-) create mode 100644 folding-schemes/src/folding/nova/nifs/mod.rs create mode 100644 folding-schemes/src/folding/nova/nifs/mova.rs rename folding-schemes/src/folding/nova/{nifs.rs => nifs/nova.rs} (50%) rename folding-schemes/src/folding/nova/{ => nifs}/ova.rs (79%) create mode 100644 folding-schemes/src/folding/nova/nifs/pointvsline.rs diff --git a/examples/circom_full_flow.rs b/examples/circom_full_flow.rs index 66eefe0..fa74a3b 100644 --- a/examples/circom_full_flow.rs +++ b/examples/circom_full_flow.rs @@ -83,6 +83,7 @@ fn main() { // prepare the Nova prover & verifier params let nova_preprocess_params = PreprocessorParam::new(poseidon_config, f_circuit.clone()); let nova_params = N::preprocess(&mut rng, &nova_preprocess_params).unwrap(); + let pp_hash = nova_params.1.pp_hash().unwrap(); // initialize the folding scheme engine, in our case we use Nova let mut nova = N::init(&nova_params, f_circuit.clone(), z_0).unwrap(); @@ -130,6 +131,7 @@ fn main() { let calldata: Vec = prepare_calldata( function_selector, + pp_hash, nova.i, nova.z_0, nova.z_i, diff --git a/examples/full_flow.rs b/examples/full_flow.rs index bf1f28f..7b586ea 100644 --- a/examples/full_flow.rs +++ b/examples/full_flow.rs @@ -101,6 +101,7 @@ fn main() { // prepare the Nova prover & verifier params let nova_preprocess_params = PreprocessorParam::new(poseidon_config.clone(), f_circuit); let nova_params = N::preprocess(&mut rng, &nova_preprocess_params).unwrap(); + let pp_hash = nova_params.1.pp_hash().unwrap(); // initialize the folding scheme engine, in our case we use Nova let mut nova = N::init(&nova_params, f_circuit, z_0).unwrap(); @@ -138,6 +139,7 @@ fn main() { let calldata: Vec = prepare_calldata( function_selector, + pp_hash, nova.i, nova.z_0, nova.z_i, diff --git a/examples/noir_full_flow.rs b/examples/noir_full_flow.rs index 9d153be..6e70873 100644 --- a/examples/noir_full_flow.rs +++ b/examples/noir_full_flow.rs @@ -72,6 +72,7 @@ fn main() { // prepare the Nova prover & verifier params let nova_preprocess_params = PreprocessorParam::new(poseidon_config, f_circuit.clone()); let nova_params = N::preprocess(&mut rng, &nova_preprocess_params).unwrap(); + let pp_hash = nova_params.1.pp_hash().unwrap(); // initialize the folding scheme engine, in our case we use Nova let mut nova = N::init(&nova_params, f_circuit.clone(), z_0).unwrap(); @@ -117,6 +118,7 @@ fn main() { let calldata: Vec = prepare_calldata( function_selector, + pp_hash, nova.i, nova.z_0, nova.z_i, diff --git a/examples/noname_full_flow.rs b/examples/noname_full_flow.rs index 6831a2e..d64493a 100644 --- a/examples/noname_full_flow.rs +++ b/examples/noname_full_flow.rs @@ -85,6 +85,7 @@ fn main() { // prepare the Nova prover & verifier params let nova_preprocess_params = PreprocessorParam::new(poseidon_config, f_circuit.clone()); let nova_params = N::preprocess(&mut rng, &nova_preprocess_params).unwrap(); + let pp_hash = nova_params.1.pp_hash().unwrap(); // initialize the folding scheme engine, in our case we use Nova let mut nova = N::init(&nova_params, f_circuit.clone(), z_0).unwrap(); @@ -132,6 +133,7 @@ fn main() { let calldata: Vec = prepare_calldata( function_selector, + pp_hash, nova.i, nova.z_0, nova.z_i, diff --git a/folding-schemes/src/folding/circuits/cyclefold.rs b/folding-schemes/src/folding/circuits/cyclefold.rs index 91a8787..a663287 100644 --- a/folding-schemes/src/folding/circuits/cyclefold.rs +++ b/folding-schemes/src/folding/circuits/cyclefold.rs @@ -24,9 +24,10 @@ use super::{nonnative::uint::NonNativeUintVar, CF1, CF2}; use crate::arith::r1cs::{extract_w_x, R1CS}; use crate::commitment::CommitmentScheme; use crate::constants::NOVA_N_BITS_RO; -use crate::folding::nova::{nifs::NIFS, traits::NIFSTrait}; +use crate::folding::nova::nifs::{nova::NIFS, NIFSTrait}; use crate::transcript::{AbsorbNonNative, AbsorbNonNativeGadget, Transcript, TranscriptVar}; use crate::Error; +use ark_crypto_primitives::sponge::poseidon::PoseidonSponge; /// Re-export the Nova committed instance as `CycleFoldCommittedInstance` and /// witness as `CycleFoldWitness`, for clarity and consistency @@ -493,6 +494,72 @@ where } } +/// CycleFoldNIFS is a wrapper on top of Nova's NIFS, which just replaces the `prove` and `verify` +/// methods to use a different ChallengeGadget, but internally reuses the other Nova's NIFS +/// methods. +/// It is a custom implementation that does not follow the NIFSTrait because it needs to work over +/// different fields than the main NIFS impls (Nova, Mova, Ova). Could be abstracted, but it's a +/// tradeoff between overcomplexity at the NIFSTrait and the (not much) need of generalization at +/// the CycleFoldNIFS. +pub struct CycleFoldNIFS< + C1: CurveGroup, + C2: CurveGroup, + GC2: CurveVar> + ToConstraintFieldGadget>, + CS2: CommitmentScheme, + const H: bool = false, +> where + ::BaseField: PrimeField, + ::BaseField: PrimeField, + for<'a> &'a GC2: GroupOpsBounds<'a, C2, GC2>, +{ + _c1: PhantomData, + _c2: PhantomData, + _gc2: PhantomData, + _cs: PhantomData, +} +impl, const H: bool> + CycleFoldNIFS +where + ::BaseField: PrimeField, + ::BaseField: PrimeField, + ::ScalarField: Absorb, + ::ScalarField: Absorb, + C1: CurveGroup, + GC2: CurveVar> + ToConstraintFieldGadget>, + for<'a> &'a GC2: GroupOpsBounds<'a, C2, GC2>, +{ + fn prove( + cf_r_Fq: C2::ScalarField, // C2::Fr==C1::Fq + cf_W_i: &CycleFoldWitness, + cf_U_i: &CycleFoldCommittedInstance, + cf_w_i: &CycleFoldWitness, + cf_u_i: &CycleFoldCommittedInstance, + aux_p: &[C2::ScalarField], // = cf_T + aux_v: C2, // = cf_cmT + ) -> Result<(CycleFoldWitness, CycleFoldCommittedInstance), Error> { + let w = NIFS::, H>::fold_witness( + cf_r_Fq, + cf_W_i, + cf_w_i, + &aux_p.to_vec(), + )?; + let ci = Self::verify(cf_r_Fq, cf_U_i, cf_u_i, &aux_v)?; + Ok((w, ci)) + } + fn verify( + r: C2::ScalarField, + U_i: &CycleFoldCommittedInstance, + u_i: &CycleFoldCommittedInstance, + cmT: &C2, // VerifierAux + ) -> Result, Error> { + Ok( + NIFS::, H>::fold_committed_instances( + r, U_i, u_i, cmT, + ), + ) + } +} + /// Folds the given cyclefold circuit and its instances. This method is abstracted from any folding /// scheme struct because it is used both by Nova & HyperNova's CycleFold. #[allow(clippy::type_complexity)] @@ -551,14 +618,15 @@ where cf_w_i.commit::(&cf_cs_params, cf_x_i.clone())?; // compute T* and cmT* for CycleFoldCircuit - let (cf_T, cf_cmT) = NIFS::::compute_cyclefold_cmT( - &cf_cs_params, - &cf_r1cs, - &cf_w_i, - &cf_u_i, - &cf_W_i, - &cf_U_i, - )?; + let (cf_T, cf_cmT) = + NIFS::, H>::compute_cyclefold_cmT( + &cf_cs_params, + &cf_r1cs, + &cf_w_i, + &cf_u_i, + &cf_W_i, + &cf_U_i, + )?; let cf_r_bits = CycleFoldChallengeGadget::::get_challenge_native( transcript, @@ -570,8 +638,11 @@ where let cf_r_Fq = C1::BaseField::from_bigint(BigInteger::from_bits_le(&cf_r_bits)) .expect("cf_r_bits out of bounds"); - let (cf_W_i1, cf_U_i1) = - NIFS::::prove(cf_r_Fq, &cf_W_i, &cf_U_i, &cf_w_i, &cf_u_i, &cf_T, &cf_cmT)?; + let (cf_W_i1, cf_U_i1) = CycleFoldNIFS::::prove( + cf_r_Fq, &cf_W_i, &cf_U_i, &cf_w_i, &cf_u_i, &cf_T, cf_cmT, + )?; + let cf_r_Fq = C1::BaseField::from_bigint(BigInteger::from_bits_le(&cf_r_bits)) + .expect("cf_r_bits out of bounds"); Ok((cf_w_i, cf_u_i, cf_W_i1, cf_U_i1, cf_cmT, cf_r_Fq)) } @@ -671,6 +742,10 @@ pub mod tests { fn test_nifs_full_gadget() { let mut rng = ark_std::test_rng(); + let poseidon_config = poseidon_canonical_config::(); + let mut transcript_v = PoseidonSponge::::new(&poseidon_config); + let pp_hash = Fr::rand(&mut rng); + // prepare the committed instances to test in-circuit let ci: Vec> = (0..2) .into_iter() @@ -685,11 +760,16 @@ pub mod tests { // make the 2nd instance a 'fresh' instance (ie. cmE=0, u=1) ci2.cmE = Projective::zero(); ci2.u = Fr::one(); - let r_bits: Vec = - Fr::rand(&mut rng).into_bigint().to_bits_le()[..NOVA_N_BITS_RO].to_vec(); - let r_Fr = Fr::from_bigint(BigInteger::from_bits_le(&r_bits)).unwrap(); - let cmT = Projective::rand(&mut rng); - let ci3 = NIFS::>::verify(r_Fr, &ci1, &ci2, &cmT); + + let cmT = Projective::rand(&mut rng); // random only for testing + let (ci3, r_bits) = NIFS::, PoseidonSponge>::verify( + &mut transcript_v, + pp_hash, + &ci1, + &ci2, + &cmT, + ) + .unwrap(); let cs = ConstraintSystem::::new_ref(); let r_bitsVar = Vec::>::new_witness(cs.clone(), || Ok(r_bits)).unwrap(); @@ -737,7 +817,7 @@ pub mod tests { .take(TestCycleFoldConfig::::IO_LEN) .collect(), }; - let cmT = Projective::rand(&mut rng); + let cmT = Projective::rand(&mut rng); // random only for testing // compute the challenge natively let pp_hash = Fq::from(42u32); // only for test diff --git a/folding-schemes/src/folding/nova/circuits.rs b/folding-schemes/src/folding/nova/circuits.rs index b657b61..b5803a2 100644 --- a/folding-schemes/src/folding/nova/circuits.rs +++ b/folding-schemes/src/folding/nova/circuits.rs @@ -529,8 +529,7 @@ pub mod tests { use ark_std::UniformRand; use crate::commitment::pedersen::Pedersen; - use crate::folding::nova::nifs::NIFS; - use crate::folding::nova::traits::NIFSTrait; + use crate::folding::nova::nifs::{nova::NIFS, NIFSTrait}; use crate::folding::traits::CommittedInstanceOps; use crate::transcript::poseidon::poseidon_canonical_config; @@ -570,9 +569,19 @@ pub mod tests { }) .collect(); let (ci1, ci2) = (ci[0].clone(), ci[1].clone()); - let r_Fr = Fr::rand(&mut rng); + let pp_hash = Fr::rand(&mut rng); let cmT = Projective::rand(&mut rng); - let ci3 = NIFS::>::verify(r_Fr, &ci1, &ci2, &cmT); + let poseidon_config = poseidon_canonical_config::(); + let mut transcript = PoseidonSponge::::new(&poseidon_config); + let (ci3, r_bits) = NIFS::, PoseidonSponge>::verify( + &mut transcript, + pp_hash, + &ci1, + &ci2, + &cmT, + ) + .unwrap(); + let r_Fr = Fr::from_bigint(BigInteger::from_bits_le(&r_bits)).unwrap(); let cs = ConstraintSystem::::new_ref(); diff --git a/folding-schemes/src/folding/nova/decider.rs b/folding-schemes/src/folding/nova/decider.rs index 901f152..e11757c 100644 --- a/folding-schemes/src/folding/nova/decider.rs +++ b/folding-schemes/src/folding/nova/decider.rs @@ -2,7 +2,7 @@ /// DeciderEth from decider_eth.rs file. /// More details can be found at the documentation page: /// https://privacy-scaling-explorations.github.io/sonobe-docs/design/nova-decider-offchain.html -use ark_crypto_primitives::sponge::Absorb; +use ark_crypto_primitives::sponge::{poseidon::PoseidonSponge, Absorb, CryptographicSponge}; use ark_ec::{AffineRepr, CurveGroup, Group}; use ark_ff::{BigInteger, PrimeField}; use ark_r1cs_std::{groups::GroupOpsBounds, prelude::CurveVar, ToConstraintFieldGadget}; @@ -13,7 +13,10 @@ use ark_std::{One, Zero}; use core::marker::PhantomData; use super::decider_circuits::{DeciderCircuit1, DeciderCircuit2}; -use super::{nifs::NIFS, traits::NIFSTrait, CommittedInstance, Nova}; +use super::{ + nifs::{nova::NIFS, NIFSTrait}, + CommittedInstance, Nova, +}; use crate::commitment::CommitmentScheme; use crate::folding::circuits::{ cyclefold::CycleFoldCommittedInstance, @@ -21,6 +24,7 @@ use crate::folding::circuits::{ CF2, }; use crate::frontend::FCircuit; +use crate::transcript::poseidon::poseidon_canonical_config; use crate::Error; use crate::{Decider as DeciderTrait, FoldingScheme}; @@ -41,7 +45,6 @@ where // cmT and r are values for the last fold, U_{i+1}=NIFS.V(r, U_i, u_i, cmT), and they are // checked in-circuit cmT: C1, - r: C1::ScalarField, // cyclefold committed instance cf_U_i: CycleFoldCommittedInstance, // the CS challenges are provided by the prover, but in-circuit they are checked to match the @@ -209,7 +212,6 @@ where .map_err(|e| Error::Other(e.to_string()))?; let cmT = circuit1.cmT.unwrap(); - let r_Fr = circuit1.r.unwrap(); let W_i1 = circuit1.W_i1.unwrap(); let cf_W_i = circuit2.cf_W_i.unwrap(); @@ -265,7 +267,6 @@ where cs1_proofs: [U_cmW_proof, U_cmE_proof], cs2_proofs: [cf_cmW_proof, cf_cmE_proof], cmT, - r: r_Fr, cf_U_i: circuit1.cf_U_i.unwrap(), cs1_challenges: [challenge_W, challenge_E], cs2_challenges: [c2_challenge_W, c2_challenge_E], @@ -286,7 +287,17 @@ where } // compute U = U_{d+1}= NIFS.V(U_d, u_d, cmT) - let U = NIFS::::verify(proof.r, running_instance, incoming_instance, &proof.cmT); + let poseidon_config = poseidon_canonical_config::(); + let mut transcript = PoseidonSponge::::new(&poseidon_config); + let (U, r_bits) = NIFS::>::verify( + &mut transcript, + vp.pp_hash, + running_instance, + incoming_instance, + &proof.cmT, + )?; + let r = C1::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) + .ok_or(Error::OutOfBounds)?; let (cmE_x, cmE_y) = NonNativeAffineVar::inputize(U.cmE)?; let (cmW_x, cmW_y) = NonNativeAffineVar::inputize(U.cmW)?; @@ -332,7 +343,7 @@ where // NIFS values: cmT_x, cmT_y, - vec![proof.r], + vec![r], ] .concat(); diff --git a/folding-schemes/src/folding/nova/decider_circuits.rs b/folding-schemes/src/folding/nova/decider_circuits.rs index cfd56c1..d15ccf0 100644 --- a/folding-schemes/src/folding/nova/decider_circuits.rs +++ b/folding-schemes/src/folding/nova/decider_circuits.rs @@ -28,8 +28,7 @@ use super::{ decider_eth_circuit::{ evaluate_gadget, KZGChallengesGadget, R1CSVar, RelaxedR1CSGadget, WitnessVar, }, - nifs::NIFS, - traits::NIFSTrait, + nifs::{nova::NIFS, NIFSTrait}, CommittedInstance, Nova, Witness, }; use crate::arith::r1cs::R1CS; @@ -114,28 +113,21 @@ where CS2: CommitmentScheme, { let mut transcript = PoseidonSponge::::new(&nova.poseidon_config); - // pp_hash is absorbed to transcript at the ChallengeGadget::get_challenge_native call + // pp_hash is absorbed to transcript at the NIFS::prove call // compute the U_{i+1}, W_{i+1} - let (T, cmT) = NIFS::::compute_cmT( + let (W_i1, U_i1, cmT, r_bits) = NIFS::, H>::prove( &nova.cs_pp, &nova.r1cs.clone(), - &nova.w_i.clone(), - &nova.u_i.clone(), - &nova.W_i.clone(), - &nova.U_i.clone(), - )?; - let r_bits = NIFS::::get_challenge( &mut transcript, nova.pp_hash, + &nova.W_i, &nova.U_i, + &nova.w_i, &nova.u_i, - &cmT, - ); + )?; let r_Fr = C1::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) .ok_or(Error::OutOfBounds)?; - let (W_i1, U_i1) = - NIFS::::prove(r_Fr, &nova.W_i, &nova.U_i, &nova.w_i, &nova.u_i, &T, &cmT)?; // compute the commitment scheme challenges used as inputs in the circuit let (cs_challenge_W, cs_challenge_E) = diff --git a/folding-schemes/src/folding/nova/decider_eth.rs b/folding-schemes/src/folding/nova/decider_eth.rs index 24d27ed..d17b3fe 100644 --- a/folding-schemes/src/folding/nova/decider_eth.rs +++ b/folding-schemes/src/folding/nova/decider_eth.rs @@ -3,7 +3,7 @@ /// More details can be found at the documentation page: /// https://privacy-scaling-explorations.github.io/sonobe-docs/design/nova-decider-onchain.html use ark_bn254::Bn254; -use ark_crypto_primitives::sponge::Absorb; +use ark_crypto_primitives::sponge::{poseidon::PoseidonSponge, Absorb, CryptographicSponge}; use ark_ec::{AffineRepr, CurveGroup, Group}; use ark_ff::{BigInteger, PrimeField}; use ark_groth16::Groth16; @@ -15,15 +15,19 @@ use ark_std::{One, Zero}; use core::marker::PhantomData; pub use super::decider_eth_circuit::DeciderEthCircuit; -use super::traits::NIFSTrait; -use super::{nifs::NIFS, CommittedInstance, Nova}; +use super::{ + nifs::{nova::NIFS, NIFSTrait}, + CommittedInstance, Nova, +}; use crate::commitment::{ kzg::{Proof as KZGProof, KZG}, pedersen::Params as PedersenParams, CommitmentScheme, }; use crate::folding::circuits::{nonnative::affine::NonNativeAffineVar, CF2}; +use crate::folding::nova::circuits::ChallengeGadget; use crate::frontend::FCircuit; +use crate::transcript::poseidon::poseidon_canonical_config; use crate::Error; use crate::{Decider as DeciderTrait, FoldingScheme}; @@ -39,7 +43,6 @@ where // cmT and r are values for the last fold, U_{i+1}=NIFS.V(r, U_i, u_i, cmT), and they are // checked in-circuit cmT: C1, - r: C1::ScalarField, // the KZG challenges are provided by the prover, but in-circuit they are checked to match // the in-circuit computed computed ones. kzg_challenges: [C1::ScalarField; 2], @@ -161,7 +164,6 @@ where .map_err(|e| Error::Other(e.to_string()))?; let cmT = circuit.cmT.unwrap(); - let r_Fr = circuit.r.unwrap(); let W_i1 = circuit.W_i1.unwrap(); // get the challenges that have been already computed when preparing the circuit inputs in @@ -193,7 +195,6 @@ where snark_proof, kzg_proofs: [U_cmW_proof, U_cmE_proof], cmT, - r: r_Fr, kzg_challenges: [challenge_W, challenge_E], }) } @@ -212,7 +213,17 @@ where } // compute U = U_{d+1}= NIFS.V(U_d, u_d, cmT) - let U = NIFS::::verify(proof.r, running_instance, incoming_instance, &proof.cmT); + let poseidon_config = poseidon_canonical_config::(); + let mut transcript = PoseidonSponge::::new(&poseidon_config); + let (U, r_bits) = NIFS::>::verify( + &mut transcript, + vp.pp_hash, + running_instance, + incoming_instance, + &proof.cmT, + )?; + let r = C1::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) + .ok_or(Error::OutOfBounds)?; let (cmE_x, cmE_y) = NonNativeAffineVar::inputize(U.cmE)?; let (cmW_x, cmW_y) = NonNativeAffineVar::inputize(U.cmW)?; @@ -235,7 +246,7 @@ where ], cmT_x, cmT_y, - vec![proof.r], + vec![r], ] .concat(); @@ -264,8 +275,10 @@ where } /// Prepares solidity calldata for calling the NovaDecider contract +#[allow(clippy::too_many_arguments)] pub fn prepare_calldata( function_signature_check: [u8; 4], + pp_hash: ark_bn254::Fr, i: ark_bn254::Fr, z_0: Vec, z_i: Vec, @@ -273,6 +286,22 @@ pub fn prepare_calldata( incoming_instance: &CommittedInstance, proof: Proof, Groth16>, ) -> Result, Error> { + // compute the challenge r + let poseidon_config = poseidon_canonical_config::(); + let mut transcript = PoseidonSponge::::new(&poseidon_config); + let r_bits = ChallengeGadget::< + ark_bn254::G1Projective, + CommittedInstance, + >::get_challenge_native( + &mut transcript, + pp_hash, + running_instance, + incoming_instance, + Some(&proof.cmT), + ); + let r = + ark_bn254::Fr::from_bigint(BigInteger::from_bits_le(&r_bits)).ok_or(Error::OutOfBounds)?; + Ok(vec![ function_signature_check.to_vec(), i.into_bigint().to_bytes_be(), // i @@ -286,7 +315,7 @@ pub fn prepare_calldata( point_to_eth_format(running_instance.cmE.into_affine())?, // U_i_cmE running_instance.u.into_bigint().to_bytes_be(), // U_i_u incoming_instance.u.into_bigint().to_bytes_be(), // u_i_u - proof.r.into_bigint().to_bytes_be(), // r + r.into_bigint().to_bytes_be(), // r running_instance .x .iter() diff --git a/folding-schemes/src/folding/nova/decider_eth_circuit.rs b/folding-schemes/src/folding/nova/decider_eth_circuit.rs index a1dd809..a8ae675 100644 --- a/folding-schemes/src/folding/nova/decider_eth_circuit.rs +++ b/folding-schemes/src/folding/nova/decider_eth_circuit.rs @@ -26,8 +26,7 @@ use core::{borrow::Borrow, marker::PhantomData}; use super::{ circuits::{ChallengeGadget, CommittedInstanceVar}, - nifs::NIFS, - traits::NIFSTrait, + nifs::{nova::NIFS, NIFSTrait}, CommittedInstance, Nova, Witness, }; use crate::commitment::{pedersen::Params as PedersenParams, CommitmentScheme}; @@ -246,27 +245,18 @@ where let mut transcript = PoseidonSponge::::new(&nova.poseidon_config); // compute the U_{i+1}, W_{i+1} - let (aux_p, aux_v) = NIFS::::compute_aux( + let (W_i1, U_i1, cmT, r_bits) = NIFS::, H>::prove( &nova.cs_pp, &nova.r1cs.clone(), - &nova.w_i.clone(), - &nova.u_i.clone(), - &nova.W_i.clone(), - &nova.U_i.clone(), - )?; - let cmT = aux_v; - let r_bits = ChallengeGadget::>::get_challenge_native( &mut transcript, nova.pp_hash, + &nova.W_i, &nova.U_i, + &nova.w_i, &nova.u_i, - Some(&cmT), - ); + )?; let r_Fr = C1::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) .ok_or(Error::OutOfBounds)?; - let (W_i1, U_i1) = NIFS::::prove( - r_Fr, &nova.W_i, &nova.U_i, &nova.w_i, &nova.u_i, &aux_p, &aux_v, - )?; // compute the KZG challenges used as inputs in the circuit let (kzg_challenge_W, kzg_challenge_E) = diff --git a/folding-schemes/src/folding/nova/mod.rs b/folding-schemes/src/folding/nova/mod.rs index d67c33b..5e701cd 100644 --- a/folding-schemes/src/folding/nova/mod.rs +++ b/folding-schemes/src/folding/nova/mod.rs @@ -1,5 +1,9 @@ /// Implements the scheme described in [Nova](https://eprint.iacr.org/2021/370.pdf) and /// [CycleFold](https://eprint.iacr.org/2023/1192.pdf). +/// +/// The structure of the Nova code is the following: +/// - NIFS implementation for Nova (nifs.rs), Mova (mova.rs), Ova (ova.rs) +/// - IVC and the Decider (offchain Decider & onchain Decider) implementations for Nova use ark_crypto_primitives::sponge::{ poseidon::{PoseidonConfig, PoseidonSponge}, Absorb, CryptographicSponge, @@ -36,14 +40,14 @@ use crate::{ use crate::{arith::Arith, commitment::CommitmentScheme}; pub mod circuits; -pub mod nifs; -pub mod ova; pub mod traits; pub mod zk; -use circuits::{AugmentedFCircuit, ChallengeGadget, CommittedInstanceVar}; -use nifs::NIFS; -use traits::NIFSTrait; +// NIFS related: +pub mod nifs; + +use circuits::{AugmentedFCircuit, CommittedInstanceVar}; +use nifs::{nova::NIFS, NIFSTrait}; // offchain decider pub mod decider; @@ -714,28 +718,21 @@ where .F .step_native(i_usize, self.z_i.clone(), external_inputs.clone())?; - // compute T and cmT for AugmentedFCircuit - let (aux_p, aux_v) = self.compute_cmT()?; - let cmT = aux_v; - - // r_bits is the r used to the RLC of the F' instances - let r_bits = ChallengeGadget::>::get_challenge_native( - &mut transcript, - self.pp_hash, - &self.U_i, - &self.u_i, - Some(&cmT), - ); - let r_Fr = C1::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) - .ok_or(Error::OutOfBounds)?; + // fold Nova instances + let (W_i1, U_i1, cmT, r_bits): (Witness, CommittedInstance, C1, Vec) = + NIFS::, H>::prove( + &self.cs_pp, + &self.r1cs, + &mut transcript, + self.pp_hash, + &self.W_i, + &self.U_i, + &self.w_i, + &self.u_i, + )?; let r_Fq = C1::BaseField::from_bigint(BigInteger::from_bits_le(&r_bits)) .ok_or(Error::OutOfBounds)?; - // fold Nova instances - let (W_i1, U_i1): (Witness, CommittedInstance) = NIFS::::prove( - r_Fr, &self.W_i, &self.U_i, &self.w_i, &self.u_i, &aux_p, &aux_v, - )?; - // folded instance output (public input, x) // u_{i+1}.x[0] = H(i+1, z_0, z_{i+1}, U_{i+1}) let u_i1_x = U_i1.hash( @@ -776,7 +773,15 @@ where }; #[cfg(test)] - NIFS::::verify_folded_instance(r_Fr, &self.U_i, &self.u_i, &U_i1, &cmT)?; + { + let r_Fr = C1::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) + .ok_or(Error::OutOfBounds)?; + let expected = + NIFS::, H>::fold_committed_instances( + r_Fr, &self.U_i, &self.u_i, &cmT, + ); + assert_eq!(U_i1, expected); + } } else { // CycleFold part: // get the vector used as public inputs 'x' in the CycleFold circuit @@ -1037,33 +1042,6 @@ where } } -impl Nova -where - C1: CurveGroup, - GC1: CurveVar> + ToConstraintFieldGadget>, - C2: CurveGroup, - GC2: CurveVar>, - FC: FCircuit, - CS1: CommitmentScheme, - CS2: CommitmentScheme, - ::BaseField: PrimeField, - ::ScalarField: Absorb, - ::ScalarField: Absorb, - C1: CurveGroup, -{ - // computes T and cmT for the AugmentedFCircuit - fn compute_cmT(&self) -> Result<(Vec, C1), Error> { - NIFS::::compute_aux( - &self.cs_pp, - &self.r1cs, - &self.w_i, - &self.u_i, - &self.W_i, - &self.U_i, - ) - } -} - impl Nova where C1: CurveGroup, diff --git a/folding-schemes/src/folding/nova/nifs/mod.rs b/folding-schemes/src/folding/nova/nifs/mod.rs new file mode 100644 index 0000000..98e40cf --- /dev/null +++ b/folding-schemes/src/folding/nova/nifs/mod.rs @@ -0,0 +1,152 @@ +/// This module defines the NIFSTrait, which is set to implement the NIFS (Non-Interactive Folding +/// Scheme) by the various schemes (Nova, Mova, Ova). +use ark_crypto_primitives::sponge::Absorb; +use ark_ec::CurveGroup; +use ark_std::fmt::Debug; +use ark_std::rand::RngCore; + +use crate::arith::r1cs::R1CS; +use crate::commitment::CommitmentScheme; +use crate::transcript::Transcript; +use crate::Error; + +pub mod mova; +pub mod nova; +pub mod ova; +pub mod pointvsline; + +/// Defines the NIFS (Non-Interactive Folding Scheme) trait, initially defined in +/// [Nova](https://eprint.iacr.org/2021/370.pdf), and it's variants +/// [Ova](https://hackmd.io/V4838nnlRKal9ZiTHiGYzw) and +/// [Mova](https://eprint.iacr.org/2024/1220.pdf). +/// `H` specifies whether the NIFS will use a blinding factor. +pub trait NIFSTrait< + C: CurveGroup, + CS: CommitmentScheme, + T: Transcript, + const H: bool = false, +> +{ + type CommittedInstance: Debug + Clone + Absorb; + type Witness: Debug + Clone; + type ProverAux: Debug + Clone; // Prover's aux params. eg. in Nova is T + type Proof: Debug + Clone; // proof. eg. in Nova is cmT + + fn new_witness(w: Vec, e_len: usize, rng: impl RngCore) -> Self::Witness; + + fn new_instance( + rng: impl RngCore, + params: &CS::ProverParams, + w: &Self::Witness, + x: Vec, + aux: Vec, // t_or_e in Ova, empty for Nova + ) -> Result; + + fn fold_witness( + r: C::ScalarField, + W: &Self::Witness, // running witness + w: &Self::Witness, // incoming witness + aux: &Self::ProverAux, + ) -> Result; + + /// NIFS.P. Returns a tuple containing the folded Witness, the folded CommittedInstance, and + /// the used challenge `r` as a vector of bits, so that it can be reused in other methods. + #[allow(clippy::type_complexity)] + #[allow(clippy::too_many_arguments)] + fn prove( + cs_prover_params: &CS::ProverParams, + r1cs: &R1CS, + transcript: &mut T, + pp_hash: C::ScalarField, + W_i: &Self::Witness, // running witness + U_i: &Self::CommittedInstance, // running committed instance + w_i: &Self::Witness, // incoming witness + u_i: &Self::CommittedInstance, // incoming committed instance + ) -> Result< + ( + Self::Witness, + Self::CommittedInstance, + Self::Proof, + Vec, + ), + Error, + >; + + /// NIFS.V. Returns the folded CommittedInstance and the used challenge `r` as a vector of + /// bits, so that it can be reused in other methods. + fn verify( + transcript: &mut T, + pp_hash: C::ScalarField, + U_i: &Self::CommittedInstance, + u_i: &Self::CommittedInstance, + proof: &Self::Proof, + ) -> Result<(Self::CommittedInstance, Vec), Error>; +} + +#[cfg(test)] +pub mod tests { + use super::*; + use crate::transcript::poseidon::poseidon_canonical_config; + use ark_crypto_primitives::sponge::{poseidon::PoseidonSponge, CryptographicSponge}; + use ark_pallas::{Fr, Projective}; + use ark_std::{test_rng, UniformRand}; + + use super::NIFSTrait; + use crate::arith::r1cs::tests::{get_test_r1cs, get_test_z}; + use crate::commitment::pedersen::Pedersen; + + /// Test method used to test the different implementations of the NIFSTrait (ie. Nova, Mova, + /// Ova). Runs a loop using the NIFS trait, and returns the last Witness and CommittedInstance + /// so that their relation can be checked. + pub(crate) fn test_nifs_opt< + N: NIFSTrait, PoseidonSponge>, + >() -> (N::Witness, N::CommittedInstance) { + let r1cs = get_test_r1cs(); + let z = get_test_z(3); + let (w, x) = r1cs.split_z(&z); + + let mut rng = ark_std::test_rng(); + let (pedersen_params, _) = Pedersen::::setup(&mut rng, r1cs.A.n_cols).unwrap(); + + let poseidon_config = poseidon_canonical_config::(); + let mut transcript_p = PoseidonSponge::::new(&poseidon_config); + let mut transcript_v = PoseidonSponge::::new(&poseidon_config); + let pp_hash = Fr::rand(&mut rng); + + // prepare the running instance + let mut W_i = N::new_witness(w.clone(), r1cs.A.n_rows, test_rng()); + let mut U_i = N::new_instance(&mut rng, &pedersen_params, &W_i, x, vec![]).unwrap(); + + let num_iters = 10; + for i in 0..num_iters { + // prepare the incoming instance + let incoming_instance_z = get_test_z(i + 4); + let (w, x) = r1cs.split_z(&incoming_instance_z); + let w_i = N::new_witness(w.clone(), r1cs.A.n_rows, test_rng()); + let u_i = N::new_instance(&mut rng, &pedersen_params, &w_i, x, vec![]).unwrap(); + + // NIFS.P + let (folded_witness, _, proof, _) = N::prove( + &pedersen_params, + &r1cs, + &mut transcript_p, + pp_hash, + &W_i, + &U_i, + &w_i, + &u_i, + ) + .unwrap(); + + // NIFS.V + let (folded_committed_instance, _) = + N::verify(&mut transcript_v, pp_hash, &U_i, &u_i, &proof).unwrap(); + + // set running_instance for next loop iteration + W_i = folded_witness; + U_i = folded_committed_instance; + } + + (W_i, U_i) + } +} diff --git a/folding-schemes/src/folding/nova/nifs/mova.rs b/folding-schemes/src/folding/nova/nifs/mova.rs new file mode 100644 index 0000000..6f3353b --- /dev/null +++ b/folding-schemes/src/folding/nova/nifs/mova.rs @@ -0,0 +1,411 @@ +/// This module contains the implementation the NIFSTrait for the +/// [Mova](https://eprint.iacr.org/2024/1220.pdf) NIFS (Non-Interactive Folding Scheme). +use ark_crypto_primitives::sponge::Absorb; +use ark_ec::{CurveGroup, Group}; +use ark_ff::PrimeField; +use ark_poly::MultilinearExtension; +use ark_serialize::{CanonicalDeserialize, CanonicalSerialize}; +use ark_std::log2; +use ark_std::rand::RngCore; +use ark_std::{One, UniformRand, Zero}; +use std::marker::PhantomData; + +use super::{ + nova::NIFS as NovaNIFS, + pointvsline::{PointVsLine, PointVsLineProof, PointvsLineEvaluationClaim}, + NIFSTrait, +}; +use crate::arith::{r1cs::R1CS, Arith}; +use crate::commitment::CommitmentScheme; +use crate::folding::circuits::CF1; +use crate::folding::traits::Dummy; +use crate::transcript::AbsorbNonNative; +use crate::transcript::Transcript; +use crate::utils::{ + mle::dense_vec_to_dense_mle, + vec::{is_zero_vec, vec_add, vec_scalar_mul}, +}; +use crate::Error; + +#[derive(Debug, Clone, Eq, PartialEq, CanonicalSerialize, CanonicalDeserialize)] +pub struct CommittedInstance { + // Random evaluation point for the E + pub rE: Vec, + // mleE is the evaluation of the MLE of E at r_E + pub mleE: C::ScalarField, + pub u: C::ScalarField, + pub cmW: C, + pub x: Vec, +} + +impl Absorb for CommittedInstance +where + C::ScalarField: Absorb, +{ + fn to_sponge_bytes(&self, _dest: &mut Vec) { + // This is never called + unimplemented!() + } + + fn to_sponge_field_elements(&self, dest: &mut Vec) { + self.u.to_sponge_field_elements(dest); + self.x.to_sponge_field_elements(dest); + self.rE.to_sponge_field_elements(dest); + self.mleE.to_sponge_field_elements(dest); + // We cannot call `to_native_sponge_field_elements(dest)` directly, as + // `to_native_sponge_field_elements` needs `F` to be `C::ScalarField`, + // but here `F` is a generic `PrimeField`. + self.cmW + .to_native_sponge_field_elements_as_vec() + .to_sponge_field_elements(dest); + } +} + +impl Dummy for CommittedInstance { + fn dummy(io_len: usize) -> Self { + Self { + rE: vec![C::ScalarField::zero(); io_len], + mleE: C::ScalarField::zero(), + u: C::ScalarField::zero(), + cmW: C::zero(), + x: vec![C::ScalarField::zero(); io_len], + } + } +} + +#[derive(Debug, Clone, Eq, PartialEq, CanonicalSerialize, CanonicalDeserialize)] +pub struct Witness { + pub E: Vec, + pub W: Vec, + pub rW: C::ScalarField, +} + +impl Dummy<&R1CS> for Witness { + fn dummy(r1cs: &R1CS) -> Self { + Self { + E: vec![C::ScalarField::zero(); r1cs.A.n_rows], + W: vec![C::ScalarField::zero(); r1cs.A.n_cols - 1 - r1cs.l], + rW: C::ScalarField::zero(), + } + } +} + +impl Witness { + pub fn new(w: Vec, e_len: usize, mut rng: impl RngCore) -> Self { + let rW = if H { + C::ScalarField::rand(&mut rng) + } else { + C::ScalarField::zero() + }; + + Self { + E: vec![C::ScalarField::zero(); e_len], + W: w, + rW, + } + } + + pub fn commit, const H: bool>( + &self, + params: &CS::ProverParams, + x: Vec, + rE: Vec, + ) -> Result, Error> { + let mut mleE = C::ScalarField::zero(); + if !is_zero_vec::(&self.E) { + let E = dense_vec_to_dense_mle(log2(self.E.len()) as usize, &self.E); + mleE = E.evaluate(&rE).ok_or(Error::NotExpectedLength( + rE.len(), + log2(self.E.len()) as usize, + ))?; + } + let cmW = CS::commit(params, &self.W, &self.rW)?; + Ok(CommittedInstance { + rE, + mleE, + u: C::ScalarField::one(), + cmW, + x, + }) + } +} + +#[derive(Debug, Clone, Eq, PartialEq, CanonicalSerialize, CanonicalDeserialize)] +pub struct Proof { + pub h_proof: PointVsLineProof, + pub mleE1_prime: C::ScalarField, + pub mleE2_prime: C::ScalarField, + pub mleT: C::ScalarField, +} + +/// Implements the Non-Interactive Folding Scheme described in section 4 of +/// [Mova](https://eprint.iacr.org/2024/1220.pdf). +/// `H` specifies whether the NIFS will use a blinding factor +pub struct NIFS< + C: CurveGroup, + CS: CommitmentScheme, + T: Transcript, + const H: bool = false, +> { + _c: PhantomData, + _cp: PhantomData, + _ct: PhantomData, +} + +impl, T: Transcript, const H: bool> + NIFSTrait for NIFS +where + ::ScalarField: Absorb, + ::BaseField: PrimeField, +{ + type CommittedInstance = CommittedInstance; + type Witness = Witness; + type ProverAux = Vec; // T in Mova's notation + type Proof = Proof; + + fn new_witness(w: Vec, e_len: usize, rng: impl RngCore) -> Self::Witness { + Witness::new::(w, e_len, rng) + } + + fn new_instance( + mut rng: impl RngCore, + params: &CS::ProverParams, + W: &Self::Witness, + x: Vec, + aux: Vec, // = r_E + ) -> Result { + let mut rE = aux.clone(); + if is_zero_vec(&rE) { + // means that we're in a fresh instance, so generate random value + rE = (0..log2(W.E.len())) + .map(|_| C::ScalarField::rand(&mut rng)) + .collect(); + } + + W.commit::(params, x, rE) + } + + // Protocol 7 - point 3 (16) + fn fold_witness( + a: C::ScalarField, + W_i: &Witness, + w_i: &Witness, + aux: &Vec, // T in Mova's notation + ) -> Result, Error> { + let a2 = a * a; + let E: Vec = vec_add( + &vec_add(&W_i.E, &vec_scalar_mul(aux, &a))?, + &vec_scalar_mul(&w_i.E, &a2), + )?; + let W: Vec = W_i + .W + .iter() + .zip(&w_i.W) + .map(|(i1, i2)| *i1 + (a * i2)) + .collect(); + + let rW = W_i.rW + a * w_i.rW; + Ok(Witness:: { E, W, rW }) + } + + /// [Mova](https://eprint.iacr.org/2024/1220.pdf)'s section 4. Protocol 8 + /// Returns a proof for the pt-vs-line operations along with the folded committed instance + /// instances and witness + #[allow(clippy::type_complexity)] + fn prove( + _cs_prover_params: &CS::ProverParams, // not used in Mova since we don't commit to T + r1cs: &R1CS, + transcript: &mut T, + pp_hash: C::ScalarField, + W_i: &Witness, + U_i: &CommittedInstance, + w_i: &Witness, + u_i: &CommittedInstance, + ) -> Result< + ( + Self::Witness, + Self::CommittedInstance, + Self::Proof, + Vec, + ), + Error, + > { + transcript.absorb(&pp_hash); + // Protocol 5 is pre-processing + transcript.absorb(U_i); + transcript.absorb(u_i); + + // Protocol 6 + let ( + h_proof, + PointvsLineEvaluationClaim { + mleE1_prime, + mleE2_prime, + rE_prime, + }, + ) = PointVsLine::::prove(transcript, U_i, u_i, W_i, w_i)?; + + // Protocol 7 + + transcript.absorb(&mleE1_prime); + transcript.absorb(&mleE2_prime); + + // compute the cross terms + let z1: Vec = [vec![U_i.u], U_i.x.to_vec(), W_i.W.to_vec()].concat(); + let z2: Vec = [vec![u_i.u], u_i.x.to_vec(), w_i.W.to_vec()].concat(); + let T = NovaNIFS::::compute_T(r1cs, U_i.u, u_i.u, &z1, &z2)?; + + let n_vars: usize = log2(W_i.E.len()) as usize; + if log2(T.len()) as usize != n_vars { + return Err(Error::NotExpectedLength(T.len(), n_vars)); + } + + let mleT = dense_vec_to_dense_mle(n_vars, &T); + let mleT_evaluated = mleT.evaluate(&rE_prime).ok_or(Error::EvaluationFail)?; + + transcript.absorb(&mleT_evaluated); + + let alpha: C::ScalarField = transcript.get_challenge(); + + let ci = Self::fold_committed_instance( + alpha, + U_i, + u_i, + &rE_prime, + &mleE1_prime, + &mleE2_prime, + &mleT_evaluated, + )?; + let w = Self::fold_witness(alpha, W_i, w_i, &T)?; + + let proof = Self::Proof { + h_proof, + mleE1_prime, + mleE2_prime, + mleT: mleT_evaluated, + }; + Ok(( + w, + ci, + proof, + vec![], // r_bits, returned to be passed as inputs to the circuit, not used at the + // current impl status + )) + } + + /// [Mova](https://eprint.iacr.org/2024/1220.pdf)'s section 4. It verifies the results from the proof + /// Both the folding and the pt-vs-line proof + /// returns the folded committed instance + fn verify( + transcript: &mut T, + pp_hash: C::ScalarField, + U_i: &CommittedInstance, + u_i: &CommittedInstance, + proof: &Proof, + ) -> Result<(Self::CommittedInstance, Vec), Error> { + transcript.absorb(&pp_hash); + transcript.absorb(U_i); + transcript.absorb(u_i); + let rE_prime = PointVsLine::::verify( + transcript, + U_i, + u_i, + &proof.h_proof, + &proof.mleE1_prime, + &proof.mleE2_prime, + )?; + + transcript.absorb(&proof.mleE1_prime); + transcript.absorb(&proof.mleE2_prime); + transcript.absorb(&proof.mleT); + + let alpha: C::ScalarField = transcript.get_challenge(); + + Ok(( + Self::fold_committed_instance( + alpha, + U_i, + u_i, + &rE_prime, + &proof.mleE1_prime, + &proof.mleE2_prime, + &proof.mleT, + )?, + vec![], + )) + } +} + +impl, T: Transcript, const H: bool> + NIFS +{ + // Protocol 7 - point 3 (15) + fn fold_committed_instance( + a: C::ScalarField, + U_i: &CommittedInstance, + u_i: &CommittedInstance, + rE_prime: &[C::ScalarField], + mleE1_prime: &C::ScalarField, + mleE2_prime: &C::ScalarField, + mleT: &C::ScalarField, + ) -> Result, Error> { + let a2 = a * a; + let mleE = *mleE1_prime + a * mleT + a2 * mleE2_prime; + let u = U_i.u + a * u_i.u; + let cmW = U_i.cmW + u_i.cmW.mul(a); + let x = U_i + .x + .iter() + .zip(&u_i.x) + .map(|(i1, i2)| *i1 + (a * i2)) + .collect::>(); + + Ok(CommittedInstance:: { + rE: rE_prime.to_vec(), + mleE, + u, + cmW, + x, + }) + } +} + +impl Arith, CommittedInstance> for R1CS> { + type Evaluation = Vec>; + + fn eval_relation( + &self, + w: &Witness, + u: &CommittedInstance, + ) -> Result { + self.eval_at_z(&[&[u.u][..], &u.x, &w.W].concat()) + } + + fn check_evaluation( + w: &Witness, + _u: &CommittedInstance, + e: Self::Evaluation, + ) -> Result<(), Error> { + (w.E == e).then_some(()).ok_or(Error::NotSatisfied) + } +} + +#[cfg(test)] +pub mod tests { + use super::*; + use ark_crypto_primitives::sponge::poseidon::PoseidonSponge; + use ark_pallas::{Fr, Projective}; + + use crate::arith::{r1cs::tests::get_test_r1cs, Arith}; + use crate::commitment::pedersen::Pedersen; + use crate::folding::nova::nifs::tests::test_nifs_opt; + + #[test] + fn test_nifs_mova() { + let (W, U) = test_nifs_opt::, PoseidonSponge>>(); + + // check the last folded instance relation + let r1cs = get_test_r1cs(); + r1cs.check_relation(&W, &U).unwrap(); + } +} diff --git a/folding-schemes/src/folding/nova/nifs.rs b/folding-schemes/src/folding/nova/nifs/nova.rs similarity index 50% rename from folding-schemes/src/folding/nova/nifs.rs rename to folding-schemes/src/folding/nova/nifs/nova.rs index 0a2d807..0323b50 100644 --- a/folding-schemes/src/folding/nova/nifs.rs +++ b/folding-schemes/src/folding/nova/nifs/nova.rs @@ -1,46 +1,56 @@ +/// This module contains the implementation the NIFSTrait for the +/// [Nova](https://eprint.iacr.org/2021/370.pdf) NIFS (Non-Interactive Folding Scheme). use ark_crypto_primitives::sponge::Absorb; use ark_ec::{CurveGroup, Group}; -use ark_ff::PrimeField; +use ark_ff::{BigInteger, PrimeField}; use ark_std::rand::RngCore; use ark_std::Zero; use std::marker::PhantomData; -use super::circuits::ChallengeGadget; -use super::traits::NIFSTrait; -use super::{CommittedInstance, Witness}; +use super::NIFSTrait; use crate::arith::r1cs::R1CS; use crate::commitment::CommitmentScheme; use crate::folding::circuits::cyclefold::{CycleFoldCommittedInstance, CycleFoldWitness}; +use crate::folding::nova::circuits::ChallengeGadget; +use crate::folding::nova::{CommittedInstance, Witness}; use crate::transcript::Transcript; use crate::utils::vec::{hadamard, mat_vec_mul, vec_add, vec_scalar_mul, vec_sub}; use crate::Error; /// Implements the Non-Interactive Folding Scheme described in section 4 of -/// [Nova](https://eprint.iacr.org/2021/370.pdf) +/// [Nova](https://eprint.iacr.org/2021/370.pdf). /// `H` specifies whether the NIFS will use a blinding factor -pub struct NIFS, const H: bool = false> { +pub struct NIFS< + C: CurveGroup, + CS: CommitmentScheme, + T: Transcript, + const H: bool = false, +> { _c: PhantomData, _cp: PhantomData, + _t: PhantomData, } -impl, const H: bool> NIFSTrait - for NIFS +impl, T: Transcript, const H: bool> + NIFSTrait for NIFS where ::ScalarField: Absorb, ::BaseField: PrimeField, + ::ScalarField: PrimeField, { type CommittedInstance = CommittedInstance; type Witness = Witness; type ProverAux = Vec; - type VerifierAux = C; + type Proof = C; fn new_witness(w: Vec, e_len: usize, rng: impl RngCore) -> Self::Witness { Witness::new::(w, e_len, rng) } fn new_instance( - W: &Self::Witness, + _rng: impl RngCore, params: &CS::ProverParams, + W: &Self::Witness, x: Vec, _aux: Vec, ) -> Result { @@ -51,7 +61,7 @@ where r: C::ScalarField, W_i: &Self::Witness, w_i: &Self::Witness, - aux: &Self::ProverAux, + aux: &Self::ProverAux, // T in Nova's notation ) -> Result { let r2 = r * r; let E: Vec = vec_add( @@ -72,65 +82,72 @@ where Ok(Self::Witness { E, rE, W, rW }) } - fn compute_aux( + fn prove( cs_prover_params: &CS::ProverParams, r1cs: &R1CS, + transcript: &mut T, + pp_hash: C::ScalarField, W_i: &Self::Witness, U_i: &Self::CommittedInstance, w_i: &Self::Witness, u_i: &Self::CommittedInstance, - ) -> Result<(Self::ProverAux, Self::VerifierAux), Error> { + ) -> Result< + ( + Self::Witness, + Self::CommittedInstance, + Self::Proof, + Vec, + ), + Error, + > { + // compute the cross terms let z1: Vec = [vec![U_i.u], U_i.x.to_vec(), W_i.W.to_vec()].concat(); let z2: Vec = [vec![u_i.u], u_i.x.to_vec(), w_i.W.to_vec()].concat(); - - // compute cross terms let T = Self::compute_T(r1cs, U_i.u, u_i.u, &z1, &z2)?; + // use r_T=0 since we don't need hiding property for cm(T) let cmT = CS::commit(cs_prover_params, &T, &C::ScalarField::zero())?; - Ok((T, cmT)) - } - fn get_challenge>( - transcript: &mut T, - pp_hash: C::ScalarField, // public params hash - U_i: &Self::CommittedInstance, - u_i: &Self::CommittedInstance, - aux: &Self::VerifierAux, // cmT - ) -> Vec { - ChallengeGadget::::get_challenge_native( + let r_bits = ChallengeGadget::::get_challenge_native( transcript, pp_hash, U_i, u_i, - Some(aux), - ) - } + Some(&cmT), + ); + let r_Fr = C::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) + .ok_or(Error::OutOfBounds)?; + + let w = Self::fold_witness(r_Fr, W_i, w_i, &T)?; - // Notice: `prove` method is implemented at the trait level. + let ci = Self::fold_committed_instances(r_Fr, U_i, u_i, &cmT); + + Ok((w, ci, cmT, r_bits)) + } fn verify( - // r comes from the transcript, and is a n-bit (N_BITS_CHALLENGE) element - r: C::ScalarField, + transcript: &mut T, + pp_hash: C::ScalarField, U_i: &Self::CommittedInstance, u_i: &Self::CommittedInstance, - cmT: &C, // VerifierAux - ) -> Self::CommittedInstance { - let r2 = r * r; - let cmE = U_i.cmE + cmT.mul(r) + u_i.cmE.mul(r2); - let u = U_i.u + r * u_i.u; - let cmW = U_i.cmW + u_i.cmW.mul(r); - let x = U_i - .x - .iter() - .zip(&u_i.x) - .map(|(a, b)| *a + (r * b)) - .collect::>(); + cmT: &C, // Proof + ) -> Result<(Self::CommittedInstance, Vec), Error> { + let r_bits = ChallengeGadget::::get_challenge_native( + transcript, + pp_hash, + U_i, + u_i, + Some(cmT), + ); + let r = C::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) + .ok_or(Error::OutOfBounds)?; - Self::CommittedInstance { cmE, u, cmW, x } + Ok((Self::fold_committed_instances(r, U_i, u_i, cmT), r_bits)) } } -impl, const H: bool> NIFS +impl, T: Transcript, const H: bool> + NIFS where ::ScalarField: Absorb, ::BaseField: PrimeField, @@ -161,26 +178,6 @@ where vec_sub(&vec_sub(&vec_add(&Az1_Bz2, &Az2_Bz1)?, &u1Cz2)?, &u2Cz1) } - /// In Nova, NIFS.P is the consecutive combination of compute_cmT with fold_instances, - /// ie. compute_cmT is part of the NIFS.P logic. - pub fn compute_cmT( - cs_prover_params: &CS::ProverParams, - r1cs: &R1CS, - w1: &Witness, - ci1: &CommittedInstance, - w2: &Witness, - ci2: &CommittedInstance, - ) -> Result<(Vec, C), Error> { - let z1: Vec = [vec![ci1.u], ci1.x.to_vec(), w1.W.to_vec()].concat(); - let z2: Vec = [vec![ci2.u], ci2.x.to_vec(), w2.W.to_vec()].concat(); - - // compute cross terms - let T = Self::compute_T(r1cs, ci1.u, ci2.u, &z1, &z2)?; - // use r_T=0 since we don't need hiding property for cm(T) - let cmT = CS::commit(cs_prover_params, &T, &C::ScalarField::zero())?; - Ok((T, cmT)) - } - pub fn compute_cyclefold_cmT( cs_prover_params: &CS::ProverParams, r1cs: &R1CS, // R1CS over C2.Fr=C1.Fq (here C=C2) @@ -202,25 +199,26 @@ where Ok((T, cmT)) } - /// Verify committed folded instance (ci) relations. Notice that this method does not open the - /// commitments, but just checks that the given committed instances (ci1, ci2) when folded - /// result in the folded committed instance (ci3) values. - pub fn verify_folded_instance( + /// folds two committed instances with the given r and cmT. This method is used by + /// Nova::verify, but also by Nova::prove and the CycleFoldNIFS::verify. + pub fn fold_committed_instances( r: C::ScalarField, - ci1: &CommittedInstance, - ci2: &CommittedInstance, - ci3: &CommittedInstance, + U_i: &CommittedInstance, + u_i: &CommittedInstance, cmT: &C, - ) -> Result<(), Error> { - let expected = Self::verify(r, ci1, ci2, cmT); - if ci3.cmE != expected.cmE - || ci3.u != expected.u - || ci3.cmW != expected.cmW - || ci3.x != expected.x - { - return Err(Error::NotSatisfied); - } - Ok(()) + ) -> CommittedInstance { + let r2 = r * r; + let cmE = U_i.cmE + cmT.mul(r) + u_i.cmE.mul(r2); + let u = U_i.u + r * u_i.u; + let cmW = U_i.cmW + u_i.cmW.mul(r); + let x = U_i + .x + .iter() + .zip(&u_i.x) + .map(|(a, b)| *a + (r * b)) + .collect::>(); + + CommittedInstance { cmE, u, cmW, x } } pub fn prove_commitments( @@ -241,101 +239,19 @@ where #[cfg(test)] pub mod tests { use super::*; - use crate::transcript::poseidon::poseidon_canonical_config; - use ark_crypto_primitives::sponge::{poseidon::PoseidonSponge, CryptographicSponge}; - use ark_ff::{BigInteger, PrimeField}; + use ark_crypto_primitives::sponge::poseidon::PoseidonSponge; use ark_pallas::{Fr, Projective}; - use ark_std::{test_rng, UniformRand}; - use crate::arith::{ - r1cs::tests::{get_test_r1cs, get_test_z}, - Arith, - }; + use crate::arith::{r1cs::tests::get_test_r1cs, Arith}; use crate::commitment::pedersen::Pedersen; - use crate::folding::nova::traits::NIFSTrait; + use crate::folding::nova::nifs::tests::test_nifs_opt; #[test] fn test_nifs_nova() { - let (W, U) = test_nifs_opt::>>(); + let (W, U) = test_nifs_opt::, PoseidonSponge>>(); // check the last folded instance relation let r1cs = get_test_r1cs(); r1cs.check_relation(&W, &U).unwrap(); } - - /// runs a loop using the NIFS trait, and returns the last Witness and CommittedInstance so - /// that their relation can be checked. - pub(crate) fn test_nifs_opt>>( - ) -> (N::Witness, N::CommittedInstance) { - let r1cs = get_test_r1cs(); - let z = get_test_z(3); - let (w, x) = r1cs.split_z(&z); - - let mut rng = ark_std::test_rng(); - let (pedersen_params, _) = Pedersen::::setup(&mut rng, r1cs.A.n_cols).unwrap(); - - let poseidon_config = poseidon_canonical_config::(); - let mut transcript = PoseidonSponge::::new(&poseidon_config); - let pp_hash = Fr::rand(&mut rng); - - // prepare the running instance - let mut running_witness = N::new_witness(w.clone(), r1cs.A.n_rows, test_rng()); - let mut running_committed_instance = - N::new_instance(&running_witness, &pedersen_params, x, vec![]).unwrap(); - - let num_iters = 10; - for i in 0..num_iters { - // prepare the incoming instance - let incoming_instance_z = get_test_z(i + 4); - let (w, x) = r1cs.split_z(&incoming_instance_z); - let incoming_witness = N::new_witness(w.clone(), r1cs.A.n_rows, test_rng()); - let incoming_committed_instance = - N::new_instance(&incoming_witness, &pedersen_params, x, vec![]).unwrap(); - - let (aux_p, aux_v) = N::compute_aux( - &pedersen_params, - &r1cs, - &running_witness, - &running_committed_instance, - &incoming_witness, - &incoming_committed_instance, - ) - .unwrap(); - - let r_bits = N::get_challenge( - &mut transcript, - pp_hash, - &running_committed_instance, - &incoming_committed_instance, - &aux_v, - ); - let r = Fr::from_bigint(BigInteger::from_bits_le(&r_bits)).unwrap(); - - // NIFS.P - let (folded_witness, _) = N::prove( - r, - &running_witness, - &running_committed_instance, - &incoming_witness, - &incoming_committed_instance, - &aux_p, - &aux_v, - ) - .unwrap(); - - // NIFS.V - let folded_committed_instance = N::verify( - r, - &running_committed_instance, - &incoming_committed_instance, - &aux_v, - ); - - // set running_instance for next loop iteration - running_witness = folded_witness; - running_committed_instance = folded_committed_instance; - } - - (running_witness, running_committed_instance) - } } diff --git a/folding-schemes/src/folding/nova/ova.rs b/folding-schemes/src/folding/nova/nifs/ova.rs similarity index 79% rename from folding-schemes/src/folding/nova/ova.rs rename to folding-schemes/src/folding/nova/nifs/ova.rs index 95bd91a..f45df1c 100644 --- a/folding-schemes/src/folding/nova/ova.rs +++ b/folding-schemes/src/folding/nova/nifs/ova.rs @@ -1,19 +1,18 @@ /// This module contains the implementation the NIFSTrait for the -/// [Ova](https://hackmd.io/V4838nnlRKal9ZiTHiGYzw) NIFS (Non-Interactive Folding Scheme) as -/// outlined in the protocol description doc: -/// authored by Benedikt Bünz. +/// [Ova](https://hackmd.io/V4838nnlRKal9ZiTHiGYzw) NIFS (Non-Interactive Folding Scheme). use ark_crypto_primitives::sponge::Absorb; use ark_ec::{CurveGroup, Group}; -use ark_ff::PrimeField; +use ark_ff::{BigInteger, PrimeField}; use ark_serialize::{CanonicalDeserialize, CanonicalSerialize}; use ark_std::fmt::Debug; use ark_std::rand::RngCore; use ark_std::{One, UniformRand, Zero}; use std::marker::PhantomData; -use super::{circuits::ChallengeGadget, traits::NIFSTrait}; +use super::NIFSTrait; use crate::arith::r1cs::R1CS; use crate::commitment::CommitmentScheme; +use crate::folding::nova::circuits::ChallengeGadget; use crate::folding::{circuits::CF1, traits::Dummy}; use crate::transcript::{AbsorbNonNative, Transcript}; use crate::utils::vec::{hadamard, mat_vec_mul, vec_scalar_mul, vec_sub}; @@ -51,7 +50,6 @@ where } } -// #[allow(dead_code)] // Clippy flag needed for now. /// A Witness in Ova is represented by `w`. It also contains a blinder which can or not be used /// when committing to the witness itself. #[derive(Debug, Clone, Eq, PartialEq, CanonicalSerialize, CanonicalDeserialize)] @@ -103,13 +101,19 @@ impl Dummy<&R1CS>> for Witness { } /// Implements the NIFS (Non-Interactive Folding Scheme) trait for Ova. -pub struct NIFS, const H: bool = false> { +pub struct NIFS< + C: CurveGroup, + CS: CommitmentScheme, + T: Transcript, + const H: bool = false, +> { _c: PhantomData, _cp: PhantomData, + _t: PhantomData, } -impl, const H: bool> NIFSTrait - for NIFS +impl, T: Transcript, const H: bool> + NIFSTrait for NIFS where ::ScalarField: Absorb, ::BaseField: PrimeField, @@ -117,15 +121,16 @@ where type CommittedInstance = CommittedInstance; type Witness = Witness; type ProverAux = (); - type VerifierAux = (); + type Proof = (); fn new_witness(w: Vec, _e_len: usize, rng: impl RngCore) -> Self::Witness { Witness::new::(w, rng) } fn new_instance( - W: &Self::Witness, + _rng: impl RngCore, params: &CS::ProverParams, + W: &Self::Witness, x: Vec, aux: Vec, // t_or_e ) -> Result { @@ -149,40 +154,55 @@ where Ok(Self::Witness { w, rW }) } - fn compute_aux( + fn prove( _cs_prover_params: &CS::ProverParams, _r1cs: &R1CS, - _W_i: &Self::Witness, - _U_i: &Self::CommittedInstance, - _w_i: &Self::Witness, - _u_i: &Self::CommittedInstance, - ) -> Result<(Self::ProverAux, Self::VerifierAux), Error> { - Ok(((), ())) - } - - fn get_challenge>( transcript: &mut T, - pp_hash: C::ScalarField, // public params hash + pp_hash: C::ScalarField, + W_i: &Self::Witness, U_i: &Self::CommittedInstance, + w_i: &Self::Witness, u_i: &Self::CommittedInstance, - _aux: &Self::VerifierAux, - ) -> Vec { - // reuse Nova's get_challenge method - ChallengeGadget::::get_challenge_native( - transcript, pp_hash, U_i, u_i, None, // empty in Ova's case - ) - } + ) -> Result< + ( + Self::Witness, + Self::CommittedInstance, + Self::Proof, + Vec, + ), + Error, + > { + let mut transcript_v = transcript.clone(); - // Notice: `prove` method is implemented at the trait level. + let r_bits = ChallengeGadget::::get_challenge_native( + transcript, pp_hash, U_i, u_i, None, // cmT not used in Ova + ); + let r_Fr = C::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) + .ok_or(Error::OutOfBounds)?; + + let w = Self::fold_witness(r_Fr, W_i, w_i, &())?; + + let (ci, _r_bits_v) = Self::verify(&mut transcript_v, pp_hash, U_i, u_i, &())?; + #[cfg(test)] + assert_eq!(_r_bits_v, r_bits); + + Ok((w, ci, (), r_bits)) + } fn verify( - // r comes from the transcript, and is a n-bit (N_BITS_CHALLENGE) element - r: C::ScalarField, + transcript: &mut T, + pp_hash: C::ScalarField, U_i: &Self::CommittedInstance, u_i: &Self::CommittedInstance, - _aux: &Self::VerifierAux, - ) -> Self::CommittedInstance { - // recall that r <==> alpha, and u <==> mu between Nova and Ova respectively + _proof: &Self::Proof, // unused in Ova + ) -> Result<(Self::CommittedInstance, Vec), Error> { + let r_bits = ChallengeGadget::::get_challenge_native( + transcript, pp_hash, U_i, u_i, None, // cmT not used in Ova + ); + let r = C::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)) + .ok_or(Error::OutOfBounds)?; + + // recall that r=alpha, and u=mu between Nova and Ova respectively let u = U_i.u + r; // u_i.u is always 1 IN ova as we just can do sequential IVC. let cmWE = U_i.cmWE + u_i.cmWE.mul(r); let x = U_i @@ -192,7 +212,7 @@ where .map(|(a, b)| *a + (r * b)) .collect::>(); - Self::CommittedInstance { cmWE, u, x } + Ok((Self::CommittedInstance { cmWE, u, x }, r_bits)) } } @@ -224,6 +244,7 @@ pub mod tests { use crate::arith::{r1cs::tests::get_test_r1cs, Arith}; use crate::commitment::pedersen::Pedersen; use crate::folding::nova::nifs::tests::test_nifs_opt; + use ark_crypto_primitives::sponge::poseidon::PoseidonSponge; // Simple auxiliary structure mainly used to help pass a witness for which we can check // easily an R1CS relation. @@ -257,7 +278,7 @@ pub mod tests { #[test] fn test_nifs_ova() { - let (W, U) = test_nifs_opt::>>(); + let (W, U) = test_nifs_opt::, PoseidonSponge>>(); // check the last folded instance relation let r1cs = get_test_r1cs(); diff --git a/folding-schemes/src/folding/nova/nifs/pointvsline.rs b/folding-schemes/src/folding/nova/nifs/pointvsline.rs new file mode 100644 index 0000000..a41c7f6 --- /dev/null +++ b/folding-schemes/src/folding/nova/nifs/pointvsline.rs @@ -0,0 +1,282 @@ +use ark_crypto_primitives::sponge::Absorb; +use ark_ec::{CurveGroup, Group}; +use ark_ff::{One, PrimeField}; +use ark_poly::univariate::DensePolynomial; +use ark_poly::{DenseMultilinearExtension, DenseUVPolynomial, Polynomial}; +use ark_serialize::{CanonicalDeserialize, CanonicalSerialize}; +use ark_std::{log2, Zero}; + +use super::mova::{CommittedInstance, Witness}; +use crate::transcript::Transcript; +use crate::utils::mle::dense_vec_to_dense_mle; +use crate::Error; + +/// Implements the Points vs Line as described in +/// [Mova](https://eprint.iacr.org/2024/1220.pdf) and Section 4.5.2 from Thaler’s book + +/// Claim from step 3 protocol 6 +pub struct PointvsLineEvaluationClaim { + pub mleE1_prime: C::ScalarField, + pub mleE2_prime: C::ScalarField, + pub rE_prime: Vec, +} +/// Proof from step 1 protocol 6 +#[derive(Debug, Clone, Eq, PartialEq, CanonicalSerialize, CanonicalDeserialize)] +pub struct PointVsLineProof { + pub h1: DensePolynomial, + pub h2: DensePolynomial, +} + +#[derive(Clone, Debug, Default)] +pub struct PointVsLine> { + _phantom_C: std::marker::PhantomData, + _phantom_T: std::marker::PhantomData, +} + +/// Protocol 6 from Mova +impl> PointVsLine +where + ::ScalarField: Absorb, +{ + pub fn prove( + transcript: &mut T, + ci1: &CommittedInstance, + ci2: &CommittedInstance, + w1: &Witness, + w2: &Witness, + ) -> Result<(PointVsLineProof, PointvsLineEvaluationClaim), Error> { + let n_vars: usize = log2(w1.E.len()) as usize; + + let mleE1 = dense_vec_to_dense_mle(n_vars, &w1.E); + let mleE2 = dense_vec_to_dense_mle(n_vars, &w2.E); + + // We have l(0) = r1, l(1) = r2 so we know that l(x) = r1 + x(r2-r1) thats why we need r2-r1 + let r1_sub_r2: Vec<::ScalarField> = ci1 + .rE + .iter() + .zip(&ci2.rE) + .map(|(&r1, r2)| r1 - r2) + .collect(); + + let h1 = compute_h(&mleE1, &ci1.rE, &r1_sub_r2)?; + let h2 = compute_h(&mleE2, &ci1.rE, &r1_sub_r2)?; + + transcript.absorb(&h1.coeffs()); + transcript.absorb(&h2.coeffs()); + + let beta_scalar = C::ScalarField::from_le_bytes_mod_order(b"beta"); + transcript.absorb(&beta_scalar); + let beta = transcript.get_challenge(); + + let mleE1_prime = h1.evaluate(&beta); + let mleE2_prime = h2.evaluate(&beta); + + let rE_prime = compute_l(&ci1.rE, &r1_sub_r2, beta)?; + + Ok(( + PointVsLineProof { h1, h2 }, + PointvsLineEvaluationClaim { + mleE1_prime, + mleE2_prime, + rE_prime, + }, + )) + } + + pub fn verify( + transcript: &mut T, + ci1: &CommittedInstance, + ci2: &CommittedInstance, + proof: &PointVsLineProof, + mleE1_prime: &::ScalarField, + mleE2_prime: &::ScalarField, + ) -> Result< + Vec<::ScalarField>, // rE=rE1'=rE2'. + Error, + > { + if proof.h1.evaluate(&C::ScalarField::zero()) != ci1.mleE { + return Err(Error::NotEqual); + } + + if proof.h2.evaluate(&C::ScalarField::one()) != ci2.mleE { + return Err(Error::NotEqual); + } + + transcript.absorb(&proof.h1.coeffs()); + transcript.absorb(&proof.h2.coeffs()); + + let beta_scalar = C::ScalarField::from_le_bytes_mod_order(b"beta"); + transcript.absorb(&beta_scalar); + let beta = transcript.get_challenge(); + + if *mleE1_prime != proof.h1.evaluate(&beta) { + return Err(Error::NotEqual); + } + + if *mleE2_prime != proof.h2.evaluate(&beta) { + return Err(Error::NotEqual); + } + + let r1_sub_r2: Vec<::ScalarField> = ci1 + .rE + .iter() + .zip(&ci2.rE) + .map(|(&r1, r2)| r1 - r2) + .collect(); + let rE_prime = compute_l(&ci1.rE, &r1_sub_r2, beta)?; + + Ok(rE_prime) + } +} + +fn compute_h( + mle: &DenseMultilinearExtension, + r1: &[F], + r1_sub_r2: &[F], +) -> Result, Error> { + let n_vars: usize = mle.num_vars; + if r1.len() != r1_sub_r2.len() || r1.len() != n_vars { + return Err(Error::NotEqual); + } + + // Initialize the polynomial vector from the evaluations in the multilinear extension. + // Each evaluation is turned into a constant polynomial. + let mut poly: Vec> = mle + .evaluations + .iter() + .map(|&x| DensePolynomial::from_coefficients_slice(&[x])) + .collect(); + + for (i, (&r1_i, &r1_sub_r2_i)) in r1.iter().zip(r1_sub_r2.iter()).enumerate().take(n_vars) { + // Create a linear polynomial r(X) = r1_i + (r1_sub_r2_i) * X (basically l) + let r = DensePolynomial::from_coefficients_slice(&[r1_i, r1_sub_r2_i]); + let half_len = 1 << (n_vars - i - 1); + + for b in 0..half_len { + let left = &poly[b << 1]; + let right = &poly[(b << 1) + 1]; + poly[b] = left + &(&r * &(right - left)); + } + } + + // After the loop, we should be left with a single polynomial, so return it. + Ok(poly.swap_remove(0)) +} + +fn compute_l(r1: &[F], r1_sub_r2: &[F], x: F) -> Result, Error> { + if r1.len() != r1_sub_r2.len() { + return Err(Error::NotEqual); + } + + // we have l(x) = r1 + x(r2-r1) so return the result + Ok(r1 + .iter() + .zip(r1_sub_r2) + .map(|(&r1, &r1_sub_r0)| r1 + x * r1_sub_r0) + .collect()) +} + +#[cfg(test)] +mod tests { + use super::{compute_h, compute_l}; + use ark_pallas::Fq; + use ark_poly::{DenseMultilinearExtension, DenseUVPolynomial}; + + #[test] + fn test_compute_h() { + let mle = DenseMultilinearExtension::from_evaluations_slice(1, &[Fq::from(1), Fq::from(2)]); + let r0 = [Fq::from(5)]; + let r1 = [Fq::from(6)]; + let r1_sub_r0: Vec = r1.iter().zip(&r0).map(|(&x, y)| x - y).collect(); + + let result = compute_h(&mle, &r0, &r1_sub_r0).unwrap(); + assert_eq!( + result, + DenseUVPolynomial::from_coefficients_slice(&[Fq::from(6), Fq::from(1)]) + ); + + let mle = DenseMultilinearExtension::from_evaluations_slice(1, &[Fq::from(1), Fq::from(2)]); + let r0 = [Fq::from(4)]; + let r1 = [Fq::from(7)]; + let r1_sub_r0: Vec = r1.iter().zip(&r0).map(|(&x, y)| x - y).collect(); + + let result = compute_h(&mle, &r0, &r1_sub_r0).unwrap(); + assert_eq!( + result, + DenseUVPolynomial::from_coefficients_slice(&[Fq::from(5), Fq::from(3)]) + ); + + let mle = DenseMultilinearExtension::from_evaluations_slice( + 2, + &[Fq::from(1), Fq::from(2), Fq::from(3), Fq::from(4)], + ); + let r0 = [Fq::from(5), Fq::from(4)]; + let r1 = [Fq::from(2), Fq::from(7)]; + let r1_sub_r0: Vec = r1.iter().zip(&r0).map(|(&x, y)| x - y).collect(); + + let result = compute_h(&mle, &r0, &r1_sub_r0).unwrap(); + assert_eq!( + result, + DenseUVPolynomial::from_coefficients_slice(&[Fq::from(14), Fq::from(3)]) + ); + let mle = DenseMultilinearExtension::from_evaluations_slice( + 3, + &[ + Fq::from(1), + Fq::from(2), + Fq::from(3), + Fq::from(4), + Fq::from(5), + Fq::from(6), + Fq::from(7), + Fq::from(8), + ], + ); + let r0 = [Fq::from(1), Fq::from(2), Fq::from(3)]; + let r1 = [Fq::from(5), Fq::from(6), Fq::from(7)]; + let r1_sub_r0: Vec = r1.iter().zip(&r0).map(|(&x, y)| x - y).collect(); + + let result = compute_h(&mle, &r0, &r1_sub_r0).unwrap(); + assert_eq!( + result, + DenseUVPolynomial::from_coefficients_slice(&[Fq::from(18), Fq::from(28)]) + ); + } + + #[test] + fn test_compute_h_errors() { + let mle = DenseMultilinearExtension::from_evaluations_slice(1, &[Fq::from(1), Fq::from(2)]); + let r0 = [Fq::from(5)]; + let r1_sub_r0 = []; + let result = compute_h(&mle, &r0, &r1_sub_r0); + assert!(result.is_err()); + + let mle = DenseMultilinearExtension::from_evaluations_slice( + 2, + &[Fq::from(1), Fq::from(2), Fq::from(1), Fq::from(2)], + ); + let r0 = [Fq::from(4)]; + let r1 = [Fq::from(7)]; + let r1_sub_r0: Vec = r1.iter().zip(&r0).map(|(&x, y)| x - y).collect(); + + let result = compute_h(&mle, &r0, &r1_sub_r0); + assert!(result.is_err()) + } + + #[test] + fn test_compute_l() { + // Test with simple non-zero values + let r1 = vec![Fq::from(1), Fq::from(2), Fq::from(3)]; + let r1_sub_r2 = vec![Fq::from(4), Fq::from(5), Fq::from(6)]; + let x = Fq::from(2); + + let expected = vec![ + Fq::from(1) + Fq::from(2) * Fq::from(4), + Fq::from(2) + Fq::from(2) * Fq::from(5), + Fq::from(3) + Fq::from(2) * Fq::from(6), + ]; + + let result = compute_l(&r1, &r1_sub_r2, x).unwrap(); + assert_eq!(result, expected); + } +} diff --git a/folding-schemes/src/folding/nova/traits.rs b/folding-schemes/src/folding/nova/traits.rs index ce325f1..8bf336a 100644 --- a/folding-schemes/src/folding/nova/traits.rs +++ b/folding-schemes/src/folding/nova/traits.rs @@ -1,6 +1,4 @@ -use ark_crypto_primitives::sponge::Absorb; use ark_ec::CurveGroup; -use ark_std::fmt::Debug; use ark_std::{rand::RngCore, UniformRand}; use super::{CommittedInstance, Witness}; @@ -8,79 +6,8 @@ use crate::arith::ArithSampler; use crate::arith::{r1cs::R1CS, Arith}; use crate::commitment::CommitmentScheme; use crate::folding::circuits::CF1; -use crate::transcript::Transcript; use crate::Error; -/// Defines the NIFS (Non-Interactive Folding Scheme) trait, initially defined in -/// [Nova](https://eprint.iacr.org/2021/370.pdf), and it's variants -/// [Ova](https://hackmd.io/V4838nnlRKal9ZiTHiGYzw) and -/// [Mova](https://eprint.iacr.org/2024/1220.pdf). -/// `H` specifies whether the NIFS will use a blinding factor. -pub trait NIFSTrait, const H: bool = false> { - type CommittedInstance: Debug + Clone + Absorb; - type Witness: Debug + Clone; - type ProverAux: Debug + Clone; // Prover's aux params - type VerifierAux: Debug + Clone; // Verifier's aux params - - fn new_witness(w: Vec, e_len: usize, rng: impl RngCore) -> Self::Witness; - fn new_instance( - w: &Self::Witness, - params: &CS::ProverParams, - x: Vec, - aux: Vec, // t_or_e in Ova, empty for Nova - ) -> Result; - - fn fold_witness( - r: C::ScalarField, - W: &Self::Witness, // running witness - w: &Self::Witness, // incoming witness - aux: &Self::ProverAux, - ) -> Result; - - /// computes the auxiliary parameters, eg. in Nova: (T, cmT), in Ova: T - fn compute_aux( - cs_prover_params: &CS::ProverParams, - r1cs: &R1CS, - W_i: &Self::Witness, - U_i: &Self::CommittedInstance, - w_i: &Self::Witness, - u_i: &Self::CommittedInstance, - ) -> Result<(Self::ProverAux, Self::VerifierAux), Error>; - - fn get_challenge>( - transcript: &mut T, - pp_hash: C::ScalarField, // public params hash - U_i: &Self::CommittedInstance, - u_i: &Self::CommittedInstance, - aux: &Self::VerifierAux, // ie. in Nova wouild be cmT, in Ova it's empty - ) -> Vec; - - /// NIFS.P. Notice that this method is implemented at the trait level, and depends on the other - /// two methods `fold_witness` and `verify`. - fn prove( - r: C::ScalarField, - W_i: &Self::Witness, // running witness - U_i: &Self::CommittedInstance, // running committed instance - w_i: &Self::Witness, // incoming witness - u_i: &Self::CommittedInstance, // incoming committed instance - aux_p: &Self::ProverAux, - aux_v: &Self::VerifierAux, - ) -> Result<(Self::Witness, Self::CommittedInstance), Error> { - let w = Self::fold_witness(r, W_i, w_i, aux_p)?; - let ci = Self::verify(r, U_i, u_i, aux_v); - Ok((w, ci)) - } - - /// NIFS.V - fn verify( - // r comes from the transcript, and is a n-bit (N_BITS_CHALLENGE) element - r: C::ScalarField, - U_i: &Self::CommittedInstance, - u_i: &Self::CommittedInstance, - aux: &Self::VerifierAux, - ) -> Self::CommittedInstance; -} - /// Implements `Arith` for R1CS, where the witness is of type [`Witness`], and /// the committed instance is of type [`CommittedInstance`]. /// diff --git a/folding-schemes/src/folding/nova/zk.rs b/folding-schemes/src/folding/nova/zk.rs index cdfbc1c..9160c71 100644 --- a/folding-schemes/src/folding/nova/zk.rs +++ b/folding-schemes/src/folding/nova/zk.rs @@ -30,8 +30,7 @@ /// paper). /// And the Use-case-2 would require a modified version of the Decider circuits. /// -use ark_crypto_primitives::sponge::CryptographicSponge; -use ark_ff::{BigInteger, PrimeField}; +use ark_ff::PrimeField; use ark_std::{One, Zero}; use crate::{ @@ -41,7 +40,7 @@ use crate::{ }; use ark_crypto_primitives::sponge::{ poseidon::{PoseidonConfig, PoseidonSponge}, - Absorb, + Absorb, CryptographicSponge, }; use ark_ec::{CurveGroup, Group}; use ark_r1cs_std::{ @@ -52,21 +51,16 @@ use ark_r1cs_std::{ use crate::{commitment::CommitmentScheme, folding::circuits::CF2, frontend::FCircuit, Error}; use super::{ - circuits::ChallengeGadget, nifs::NIFS, traits::NIFSTrait, CommittedInstance, Nova, Witness, + nifs::{nova::NIFS, NIFSTrait}, + CommittedInstance, Nova, Witness, }; -// We use the same definition of a folding proof as in https://eprint.iacr.org/2023/969.pdf -// It consists in the commitment to the T term -pub struct FoldingProof { - cmT: C, -} - pub struct RandomizedIVCProof { pub U_i: CommittedInstance, pub u_i: CommittedInstance, pub U_r: CommittedInstance, - pub pi: FoldingProof, - pub pi_prime: FoldingProof, + pub pi: C1, // proof = cmT + pub pi_prime: C1, // proof' = cmT' pub W_i_prime: Witness, pub cf_U_i: CommittedInstance, pub cf_W_i: Witness, @@ -77,24 +71,6 @@ where ::ScalarField: Absorb, ::BaseField: PrimeField, { - /// Computes challenge required before folding instances - fn get_folding_challenge( - sponge: &mut PoseidonSponge, - pp_hash: C1::ScalarField, - U_i: CommittedInstance, - u_i: CommittedInstance, - cmT: C1, - ) -> Result { - let r_bits = ChallengeGadget::>::get_challenge_native( - sponge, - pp_hash, - &U_i, - &u_i, - Some(&cmT), - ); - C1::ScalarField::from_bigint(BigInteger::from_bits_le(&r_bits)).ok_or(Error::OutOfBounds) - } - /// Compute a zero-knowledge proof of a Nova IVC proof /// It implements the prover of appendix D.4.in https://eprint.iacr.org/2023/573.pdf /// For further details on why folding is hiding, see lemma 9 @@ -118,68 +94,45 @@ where GC2: ToConstraintFieldGadget<::BaseField>, C1: CurveGroup, { - let mut challenges_sponge = PoseidonSponge::::new(&nova.poseidon_config); + let mut transcript = PoseidonSponge::::new(&nova.poseidon_config); // I. Compute proof for 'regular' instances // 1. Fold the instance-witness pairs (U_i, W_i) with (u_i, w_i) - // a. Compute T - let (T, cmT) = NIFS::::compute_cmT( + let (W_f, U_f, cmT, _) = NIFS::, true>::prove( &nova.cs_pp, &nova.r1cs, + &mut transcript, + nova.pp_hash, &nova.w_i, &nova.u_i, &nova.W_i, &nova.U_i, )?; - // b. Compute folding challenge - let r = RandomizedIVCProof::::get_folding_challenge( - &mut challenges_sponge, - nova.pp_hash, - nova.U_i.clone(), - nova.u_i.clone(), - cmT, - )?; - - // c. Compute fold - let (W_f, U_f) = - NIFS::::prove(r, &nova.w_i, &nova.u_i, &nova.W_i, &nova.U_i, &T, &cmT)?; - - // d. Store folding proof - let pi = FoldingProof { cmT }; - // 2. Sample a satisfying relaxed R1CS instance-witness pair (W_r, U_r) let (W_r, U_r) = nova .r1cs .sample_witness_instance::(&nova.cs_pp, &mut rng)?; // 3. Fold the instance-witness pair (U_f, W_f) with (U_r, W_r) - // a. Compute T - let (T_i_prime, cmT_i_prime) = - NIFS::::compute_cmT(&nova.cs_pp, &nova.r1cs, &W_f, &U_f, &W_r, &U_r)?; - - // b. Compute folding challenge - let r_2 = RandomizedIVCProof::::get_folding_challenge( - &mut challenges_sponge, - nova.pp_hash, - U_f.clone(), - U_r.clone(), - cmT_i_prime, - )?; - - // c. Compute fold - let (W_i_prime, _) = - NIFS::::prove(r_2, &W_f, &U_f, &W_r, &U_r, &T_i_prime, &cmT_i_prime)?; - - // d. Store folding proof - let pi_prime = FoldingProof { cmT: cmT_i_prime }; + let (W_i_prime, _, cmT_i_prime, _) = + NIFS::, true>::prove( + &nova.cs_pp, + &nova.r1cs, + &mut transcript, + nova.pp_hash, + &W_f, + &U_f, + &W_r, + &U_r, + )?; Ok(RandomizedIVCProof { U_i: nova.U_i.clone(), u_i: nova.u_i.clone(), U_r, - pi, - pi_prime, + pi: cmT, + pi_prime: cmT_i_prime, W_i_prime, cf_U_i: nova.cf_U_i.clone(), cf_W_i: nova.cf_W_i.clone(), @@ -228,7 +181,7 @@ where } // b. Check computed hashes are correct - let mut sponge = PoseidonSponge::::new(poseidon_config); + let sponge = PoseidonSponge::::new(poseidon_config); let expected_u_i_x = proof.U_i.hash(&sponge, pp_hash, i, &z_0, &z_i); if expected_u_i_x != proof.u_i.x[0] { return Err(Error::zkIVCVerificationFail); @@ -244,32 +197,25 @@ where return Err(Error::zkIVCVerificationFail); } + let mut transcript = PoseidonSponge::::new(poseidon_config); // 3. Obtain the U_f folded instance - // a. Compute folding challenge - let r = RandomizedIVCProof::::get_folding_challenge( - &mut sponge, + let (U_f, _) = NIFS::, true>::verify( + &mut transcript, pp_hash, - proof.U_i.clone(), - proof.u_i.clone(), - proof.pi.cmT, + &proof.u_i, + &proof.U_i, + &proof.pi, )?; - // b. Get the U_f instance - let U_f = NIFS::::verify(r, &proof.u_i, &proof.U_i, &proof.pi.cmT); - // 4. Obtain the U^{\prime}_i folded instance - // a. Compute folding challenge - let r_2 = RandomizedIVCProof::::get_folding_challenge( - &mut sponge, + let (U_i_prime, _) = NIFS::, true>::verify( + &mut transcript, pp_hash, - U_f.clone(), - proof.U_r.clone(), - proof.pi_prime.cmT, + &U_f, + &proof.U_r, + &proof.pi_prime, )?; - // b. Compute fold - let U_i_prime = NIFS::::verify(r_2, &U_f, &proof.U_r, &proof.pi_prime.cmT); - // 5. Check that W^{\prime}_i is a satisfying witness r1cs.check_relation(&proof.W_i_prime, &U_i_prime)?; diff --git a/solidity-verifiers/src/verifiers/nova_cyclefold.rs b/solidity-verifiers/src/verifiers/nova_cyclefold.rs index e82bd1f..86e7098 100644 --- a/solidity-verifiers/src/verifiers/nova_cyclefold.rs +++ b/solidity-verifiers/src/verifiers/nova_cyclefold.rs @@ -366,6 +366,7 @@ mod tests { n_steps: usize, ) { let (decider_pp, decider_vp) = decider_params; + let pp_hash = fs_params.1.pp_hash().unwrap(); let f_circuit = FC::new(()).unwrap(); @@ -400,6 +401,7 @@ mod tests { let calldata: Vec = prepare_calldata( function_selector, + pp_hash, nova.i, nova.z_0, nova.z_i,