mirror of
https://github.com/arnaucube/hyperplonk.git
synced 2026-01-10 16:11:29 +01:00
Prod check (#61)
This commit is contained in:
@@ -52,7 +52,7 @@ pub struct VirtualPolynomial<F: PrimeField> {
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raw_pointers_lookup_table: HashMap<*const DenseMultilinearExtension<F>, usize>,
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}
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#[derive(Clone, Debug, Default, PartialEq, CanonicalSerialize)]
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#[derive(Clone, Debug, Default, PartialEq, Eq, CanonicalSerialize)]
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/// Auxiliary information about the multilinear polynomial
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pub struct VPAuxInfo<F: PrimeField> {
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/// max number of multiplicands in each product
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@@ -165,7 +165,7 @@ pub struct HyperPlonkVerifyingKey<E: PairingEngine, PCS: PolynomialCommitmentSch
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/// id_w2 = 1 // second witness
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///
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/// NOTE: here coeff is a signed integer, instead of a field element
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#[derive(Clone, Debug, Default, PartialEq)]
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#[derive(Clone, Debug, Default, PartialEq, Eq)]
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pub struct CustomizedGates {
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pub(crate) gates: Vec<(i64, Option<usize>, Vec<usize>)>,
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}
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@@ -1,7 +1,7 @@
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use ark_ec::PairingEngine;
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use ark_serialize::{CanonicalDeserialize, CanonicalSerialize, Read, SerializationError, Write};
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#[derive(CanonicalSerialize, CanonicalDeserialize, Clone, Debug, Default, PartialEq)]
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#[derive(CanonicalSerialize, CanonicalDeserialize, Clone, Debug, Default, PartialEq, Eq)]
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/// A commitment is an Affine point.
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pub struct Commitment<E: PairingEngine> {
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/// the actual commitment is an affine point.
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@@ -6,12 +6,14 @@ edition = "2021"
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# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
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[dependencies]
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pcs = { path = "../pcs" }
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ark-ff = { version = "^0.3.0", default-features = false }
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ark-std = { version = "^0.3.0", default-features = false }
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ark-poly = { version = "^0.3.0", default-features = false }
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ark-serialize = { version = "^0.3.0", default-features = false }
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ark-bls12-381 = { version = "0.3.0", default-features = false, features = [ "curve" ] }
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ark-ec = { version = "^0.3.0", default-features = false }
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rand_chacha = { version = "0.3.0", default-features = false }
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displaydoc = { version = "0.2.3", default-features = false }
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@@ -37,7 +39,8 @@ parallel = [
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"arithmetic/parallel",
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"ark-std/parallel",
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"ark-ff/parallel",
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"ark-poly/parallel"
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"ark-poly/parallel",
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"pcs/parallel",
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]
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print-trace = [
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"arithmetic/print-trace",
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@@ -3,6 +3,7 @@
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use arithmetic::ArithErrors;
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use ark_std::string::String;
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use displaydoc::Display;
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use pcs::prelude::PCSErrors;
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use transcript::TranscriptErrors;
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/// A `enum` specifying the possible failure modes of the PolyIOP.
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@@ -26,6 +27,8 @@ pub enum PolyIOPErrors {
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TranscriptErrors(TranscriptErrors),
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/// Arithmetic Error: {0}
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ArithmeticErrors(ArithErrors),
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/// PCS error {0}
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PCSErrors(PCSErrors),
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}
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impl From<ark_serialize::SerializationError> for PolyIOPErrors {
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@@ -45,3 +48,9 @@ impl From<ArithErrors> for PolyIOPErrors {
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Self::ArithmeticErrors(e)
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}
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}
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impl From<PCSErrors> for PolyIOPErrors {
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fn from(e: PCSErrors) -> Self {
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Self::PCSErrors(e)
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}
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}
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@@ -1,37 +1,49 @@
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//! Main module for the Permutation Check protocol
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//! Main module for the Product Check protocol
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use crate::{errors::PolyIOPErrors, ZeroCheck};
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use arithmetic::VirtualPolynomial;
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use ark_ff::PrimeField;
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use crate::{
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errors::PolyIOPErrors,
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prod_check::util::{compute_product_poly, prove_zero_check},
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PolyIOP, ZeroCheck,
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};
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use arithmetic::VPAuxInfo;
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use ark_ec::PairingEngine;
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use ark_ff::{One, PrimeField, Zero};
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use ark_poly::DenseMultilinearExtension;
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use ark_std::{end_timer, start_timer};
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use pcs::prelude::PolynomialCommitmentScheme;
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use std::{marker::PhantomData, rc::Rc};
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use transcript::IOPTranscript;
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mod util;
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/// A product-check proves that two n-variate multilinear polynomials `f(x),
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/// g(x)` satisfy:
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/// \prod_{x \in {0,1}^n} f(x) = \prod_{x \in {0,1}^n} g(x)
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///
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/// A ProductCheck is derived from ZeroCheck.
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///
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/// A ProductCheck IOP takes the following steps:
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///
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/// Inputs:
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/// - f(x)
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///
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/// Prover steps:
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/// 1. `compute_product_poly` to build `prod(x0, ..., x_n)` from virtual
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/// polynomial f
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/// 2. push commitments of `f(x)`, `prod(x)` to the transcript
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/// (done by the snark caller)
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/// 3. `generate_challenge` from current transcript (generate alpha)
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/// 4. `prove` to generate the zerocheck proof for the virtual polynomial
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/// prod(1, x) - prod(x, 0) * prod(x, 1) + alpha * (f(x) - prod(0, x))
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/// 1. build `prod(x0, ..., x_n)` from f and g,
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/// such that `prod(0, x1, ..., xn)` equals `f/g` over domain {0,1}^n
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/// 2. push commitments of `prod(x)` to the transcript,
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/// and `generate_challenge` from current transcript (generate alpha)
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/// 3. generate the zerocheck proof for the virtual polynomial
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/// prod(1, x) - prod(x, 0) * prod(x, 1) + alpha * (f(x) - prod(0, x) * g(x))
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///
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/// Verifier steps:
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/// 1. Extract commitments of `f(x)`, `prod(x)` from the proof, push them to the
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/// transcript (done by the snark caller)
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/// 1. Extract commitments of `prod(x)` from the proof, push
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/// them to the transcript
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/// 2. `generate_challenge` from current transcript (generate alpha)
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/// 3. `verify` to verify the zerocheck proof and generate the subclaim for
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/// polynomial evaluations
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pub trait ProductCheck<F: PrimeField>: ZeroCheck<F> {
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pub trait ProductCheck<E, PCS>: ZeroCheck<E::Fr>
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where
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E: PairingEngine,
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PCS: PolynomialCommitmentScheme<E>,
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{
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type ProductCheckSubClaim;
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type ProductCheckChallenge;
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type ProductProof;
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type Polynomial;
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/// Initialize the system with a transcript
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///
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@@ -41,58 +53,44 @@ pub trait ProductCheck<F: PrimeField>: ZeroCheck<F> {
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/// ProductCheck prover/verifier.
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fn init_transcript() -> Self::Transcript;
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/// Generate random challenge `alpha` from a transcript.
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fn generate_challenge(
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transcript: &mut Self::Transcript,
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) -> Result<Self::ProductCheckChallenge, PolyIOPErrors>;
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/// Compute the product polynomial `prod(x)` where
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///
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/// - `prod(0,x) := prod(0, x1, …, xn)` is the MLE over the
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/// evaluations of `f(x)` on the boolean hypercube {0,1}^n
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///
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/// - `prod(1,x)` is a MLE over the evaluations of `prod(x, 0) * prod(x, 1)`
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/// on the boolean hypercube {0,1}^n
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///
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/// The caller needs to check num_vars matches in f
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/// Cost: linear in N.
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fn compute_product_poly(
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fx: &VirtualPolynomial<F>,
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) -> Result<DenseMultilinearExtension<F>, PolyIOPErrors>;
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/// Initialize the prover to argue that for a virtual polynomial f(x),
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/// it holds that `s = \prod_{x \in {0,1}^n} f(x)`
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/// Generate a proof for product check, showing that witness multilinear
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/// polynomials f(x), g(x) satisfy `\prod_{x \in {0,1}^n} f(x) =
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/// \prod_{x \in {0,1}^n} g(x)`
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///
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/// Inputs:
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/// - fx: the virtual polynomial
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/// - prod_x: the product polynomial
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/// - transcript: a transcript that is used to generate the challenges alpha
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/// - claimed_product: the claimed product value
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/// - fx: the numerator multilinear polynomial
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/// - gx: the denominator multilinear polynomial
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/// - transcript: the IOP transcript
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/// - pk: PCS committing key
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///
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/// Outputs
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/// - the product check proof
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/// - the product polynomial (used for testing)
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///
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/// Cost: O(N)
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fn prove(
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fx: &VirtualPolynomial<F>,
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prod_x: &DenseMultilinearExtension<F>,
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transcript: &mut IOPTranscript<F>,
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claimed_product: F,
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) -> Result<Self::ProductProof, PolyIOPErrors>;
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fx: &Self::Polynomial,
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gx: &Self::Polynomial,
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transcript: &mut IOPTranscript<E::Fr>,
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pk: &PCS::ProverParam,
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) -> Result<(Self::ProductProof, Self::Polynomial), PolyIOPErrors>;
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/// Verify that for a witness virtual polynomial f(x),
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/// it holds that `s = \prod_{x \in {0,1}^n} f(x)`
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/// Verify that for witness multilinear polynomials f(x), g(x)
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/// it holds that `\prod_{x \in {0,1}^n} f(x) = \prod_{x \in {0,1}^n} g(x)`
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fn verify(
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proof: &Self::ProductProof,
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aux_info: &Self::VPAuxInfo,
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num_vars: usize,
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transcript: &mut Self::Transcript,
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claimed_product: F,
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) -> Result<Self::ProductCheckSubClaim, PolyIOPErrors>;
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}
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/// A product check subclaim consists of
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/// - A zero check IOP subclaim for
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/// `Q(x) = prod(1, x) - prod(x, 0) * prod(x, 1) + alpha * (f(x) - prod(0, x)`
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/// is 0, consists of the following:
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/// `Q(x) = prod(1, x) - prod(x, 0) * prod(x, 1) + challenge * (f(x) - prod(0,
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/// x) * g(x))` is 0, consists of the following:
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/// - the SubClaim from the SumCheck
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/// - the initial challenge r which is used to build eq(x, r) in ZeroCheck
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/// - The challenge `challenge`
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/// - A final query for `prod(1, ..., 1, 0) = claimed_product`.
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// Note that this final query is in fact a constant that
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// is independent from the proof. So we should avoid
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@@ -102,16 +100,200 @@ pub struct ProductCheckSubClaim<F: PrimeField, ZC: ZeroCheck<F>> {
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// the SubClaim from the ZeroCheck
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zero_check_sub_claim: ZC::ZeroCheckSubClaim,
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// final query which consists of
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// - the vector `(1, ..., 1, 0)`
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// - the evaluation `claimed_product`
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// - the vector `(1, ..., 1, 0)` (needs to be reversed because Arkwork's MLE uses big-endian
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// format for points)
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// The expected final query evaluation is 1
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final_query: (Vec<F>, F),
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challenge: F,
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}
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/// The random challenges in a product check protocol
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#[allow(dead_code)]
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pub struct ProductCheckChallenge<F: PrimeField> {
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alpha: F,
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/// A product check proof consists of
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/// - a zerocheck proof
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/// - a product polynomial commitment
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#[derive(Clone, Debug, Default, PartialEq)]
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pub struct ProductProof<E: PairingEngine, PCS: PolynomialCommitmentScheme<E>, ZC: ZeroCheck<E::Fr>>
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{
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zero_check_proof: ZC::ZeroCheckProof,
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prod_x_comm: PCS::Commitment,
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}
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impl<E, PCS> ProductCheck<E, PCS> for PolyIOP<E::Fr>
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where
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E: PairingEngine,
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PCS: PolynomialCommitmentScheme<E, Polynomial = Rc<DenseMultilinearExtension<E::Fr>>>,
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{
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type ProductCheckSubClaim = ProductCheckSubClaim<E::Fr, Self>;
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type ProductProof = ProductProof<E, PCS, Self>;
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type Polynomial = Rc<DenseMultilinearExtension<E::Fr>>;
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fn init_transcript() -> Self::Transcript {
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IOPTranscript::<E::Fr>::new(b"Initializing ProductCheck transcript")
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}
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fn prove(
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fx: &Self::Polynomial,
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gx: &Self::Polynomial,
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transcript: &mut IOPTranscript<E::Fr>,
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pk: &PCS::ProverParam,
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) -> Result<(Self::ProductProof, Self::Polynomial), PolyIOPErrors> {
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let start = start_timer!(|| "prod_check prove");
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if fx.num_vars != gx.num_vars {
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return Err(PolyIOPErrors::InvalidParameters(
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"fx and gx have different number of variables".to_string(),
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));
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}
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// compute the product polynomial
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let prod_x = compute_product_poly(fx, gx)?;
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// generate challenge
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let prod_x_comm = PCS::commit(pk, &Rc::new(prod_x.clone()))?;
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transcript.append_serializable_element(b"prod(x)", &prod_x_comm)?;
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let alpha = transcript.get_and_append_challenge(b"alpha")?;
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// build the zero-check proof
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let (zero_check_proof, _) = prove_zero_check(fx, gx, &prod_x, &alpha, transcript)?;
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end_timer!(start);
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Ok((
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ProductProof {
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zero_check_proof,
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prod_x_comm,
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},
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Rc::new(prod_x.clone()),
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))
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}
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fn verify(
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proof: &Self::ProductProof,
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num_vars: usize,
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transcript: &mut Self::Transcript,
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) -> Result<Self::ProductCheckSubClaim, PolyIOPErrors> {
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let start = start_timer!(|| "prod_check verify");
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// update transcript and generate challenge
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transcript.append_serializable_element(b"prod(x)", &proof.prod_x_comm)?;
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let alpha = transcript.get_and_append_challenge(b"alpha")?;
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// invoke the zero check on the iop_proof
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// the virtual poly info for Q(x)
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let aux_info = VPAuxInfo {
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max_degree: 2,
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num_variables: num_vars,
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phantom: PhantomData::default(),
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};
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let zero_check_sub_claim =
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<Self as ZeroCheck<E::Fr>>::verify(&proof.zero_check_proof, &aux_info, transcript)?;
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// the final query is on prod_x, hence has length `num_vars` + 1
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let mut final_query = vec![E::Fr::one(); aux_info.num_variables + 1];
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// the point has to be reversed because Arkworks uses big-endian.
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final_query[0] = E::Fr::zero();
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let final_eval = E::Fr::one();
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end_timer!(start);
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Ok(ProductCheckSubClaim {
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zero_check_sub_claim,
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final_query: (final_query, final_eval),
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challenge: alpha,
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})
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}
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}
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#[cfg(test)]
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mod test {}
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mod test {
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use super::ProductCheck;
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use crate::{errors::PolyIOPErrors, PolyIOP};
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use ark_bls12_381::{Bls12_381, Fr};
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use ark_ec::PairingEngine;
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use ark_poly::{DenseMultilinearExtension, MultilinearExtension};
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use ark_std::test_rng;
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use pcs::{prelude::KZGMultilinearPCS, PolynomialCommitmentScheme};
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use std::rc::Rc;
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// f and g are guaranteed to have the same product
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fn test_product_check_helper<E, PCS>(
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f: &DenseMultilinearExtension<E::Fr>,
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g: &DenseMultilinearExtension<E::Fr>,
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pk: &PCS::ProverParam,
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) -> Result<(), PolyIOPErrors>
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where
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E: PairingEngine,
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PCS: PolynomialCommitmentScheme<E, Polynomial = Rc<DenseMultilinearExtension<E::Fr>>>,
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{
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let mut transcript = <PolyIOP<E::Fr> as ProductCheck<E, PCS>>::init_transcript();
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transcript.append_message(b"testing", b"initializing transcript for testing")?;
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let (proof, prod_x) = <PolyIOP<E::Fr> as ProductCheck<E, PCS>>::prove(
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&Rc::new(f.clone()),
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&Rc::new(g.clone()),
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&mut transcript,
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pk,
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)?;
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let mut transcript = <PolyIOP<E::Fr> as ProductCheck<E, PCS>>::init_transcript();
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transcript.append_message(b"testing", b"initializing transcript for testing")?;
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let subclaim =
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<PolyIOP<E::Fr> as ProductCheck<E, PCS>>::verify(&proof, f.num_vars, &mut transcript)?;
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assert_eq!(
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prod_x.evaluate(&subclaim.final_query.0).unwrap(),
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subclaim.final_query.1,
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"different product"
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);
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// bad path
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let mut transcript = <PolyIOP<E::Fr> as ProductCheck<E, PCS>>::init_transcript();
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transcript.append_message(b"testing", b"initializing transcript for testing")?;
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let h = f + g;
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let (bad_proof, prod_x_bad) = <PolyIOP<E::Fr> as ProductCheck<E, PCS>>::prove(
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&Rc::new(f.clone()),
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&Rc::new(h.clone()),
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&mut transcript,
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pk,
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)?;
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let mut transcript = <PolyIOP<E::Fr> as ProductCheck<E, PCS>>::init_transcript();
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transcript.append_message(b"testing", b"initializing transcript for testing")?;
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let bad_subclaim = <PolyIOP<E::Fr> as ProductCheck<E, PCS>>::verify(
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&bad_proof,
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f.num_vars,
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&mut transcript,
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)?;
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assert_ne!(
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prod_x_bad.evaluate(&bad_subclaim.final_query.0).unwrap(),
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bad_subclaim.final_query.1,
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"can't detect wrong proof"
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);
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Ok(())
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}
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fn test_product_check(nv: usize) -> Result<(), PolyIOPErrors> {
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let mut rng = test_rng();
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let f: DenseMultilinearExtension<Fr> = DenseMultilinearExtension::rand(nv, &mut rng);
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let mut g = f.clone();
|
||||
g.evaluations.reverse();
|
||||
|
||||
let srs = KZGMultilinearPCS::<Bls12_381>::gen_srs_for_testing(&mut rng, nv + 1)?;
|
||||
let (pk, _) = KZGMultilinearPCS::<Bls12_381>::trim(&srs, nv + 1, Some(nv + 1))?;
|
||||
|
||||
test_product_check_helper::<Bls12_381, KZGMultilinearPCS<Bls12_381>>(&f, &g, &pk)?;
|
||||
|
||||
Ok(())
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn test_trivial_polynomial() -> Result<(), PolyIOPErrors> {
|
||||
test_product_check(1)
|
||||
}
|
||||
#[test]
|
||||
fn test_normal_polynomial() -> Result<(), PolyIOPErrors> {
|
||||
test_product_check(10)
|
||||
}
|
||||
}
|
||||
|
||||
192
poly-iop/src/prod_check/util.rs
Normal file
192
poly-iop/src/prod_check/util.rs
Normal file
@@ -0,0 +1,192 @@
|
||||
//! This module implements useful functions for the product check protocol.
|
||||
|
||||
use crate::{errors::PolyIOPErrors, structs::IOPProof, utils::get_index, PolyIOP, ZeroCheck};
|
||||
use arithmetic::VirtualPolynomial;
|
||||
use ark_ff::PrimeField;
|
||||
use ark_poly::DenseMultilinearExtension;
|
||||
use ark_std::{end_timer, start_timer};
|
||||
use std::rc::Rc;
|
||||
use transcript::IOPTranscript;
|
||||
|
||||
/// Compute the product polynomial `prod(x)` where
|
||||
///
|
||||
/// - `prod(0,x) := prod(0, x1, …, xn)` is the MLE over the
|
||||
/// evaluations of `f(x)/g(x)` on the boolean hypercube {0,1}^n
|
||||
///
|
||||
/// - `prod(1,x)` is a MLE over the evaluations of `prod(x, 0) * prod(x, 1)`
|
||||
/// on the boolean hypercube {0,1}^n
|
||||
///
|
||||
/// The caller needs to check num_vars matches in f and g
|
||||
/// Cost: linear in N.
|
||||
pub(super) fn compute_product_poly<F: PrimeField>(
|
||||
fx: &DenseMultilinearExtension<F>,
|
||||
gx: &DenseMultilinearExtension<F>,
|
||||
) -> Result<DenseMultilinearExtension<F>, PolyIOPErrors> {
|
||||
let start = start_timer!(|| "compute evaluations of prod polynomial");
|
||||
let num_vars = fx.num_vars;
|
||||
|
||||
// ===================================
|
||||
// prod(0, x)
|
||||
// ===================================
|
||||
let prod_0x_eval = compute_prod_0(fx, gx)?;
|
||||
|
||||
// ===================================
|
||||
// prod(1, x)
|
||||
// ===================================
|
||||
//
|
||||
// `prod(1, x)` can be computed via recursing the following formula for 2^n-1
|
||||
// times
|
||||
//
|
||||
// `prod(1, x_1, ..., x_n) :=
|
||||
// prod(x_1, x_2, ..., x_n, 0) * prod(x_1, x_2, ..., x_n, 1)`
|
||||
//
|
||||
// At any given step, the right hand side of the equation
|
||||
// is available via either eval_0x or the current view of eval_1x
|
||||
let mut prod_1x_eval = vec![];
|
||||
for x in 0..(1 << num_vars) - 1 {
|
||||
// sign will decide if the evaluation should be looked up from eval_0x or
|
||||
// eval_1x; x_zero_index is the index for the evaluation (x_2, ..., x_n,
|
||||
// 0); x_one_index is the index for the evaluation (x_2, ..., x_n, 1);
|
||||
let (x_zero_index, x_one_index, sign) = get_index(x, num_vars);
|
||||
if !sign {
|
||||
prod_1x_eval.push(prod_0x_eval[x_zero_index] * prod_0x_eval[x_one_index]);
|
||||
} else {
|
||||
// sanity check: if we are trying to look up from the eval_1x table,
|
||||
// then the target index must already exist
|
||||
if x_zero_index >= prod_1x_eval.len() || x_one_index >= prod_1x_eval.len() {
|
||||
return Err(PolyIOPErrors::ShouldNotArrive);
|
||||
}
|
||||
prod_1x_eval.push(prod_1x_eval[x_zero_index] * prod_1x_eval[x_one_index]);
|
||||
}
|
||||
}
|
||||
|
||||
// prod(1, 1, ..., 1) := 0
|
||||
prod_1x_eval.push(F::zero());
|
||||
|
||||
// ===================================
|
||||
// prod(x)
|
||||
// ===================================
|
||||
// prod(x)'s evaluation is indeed `e := [eval_0x[..], eval_1x[..]].concat()`
|
||||
let eval = [prod_0x_eval.as_slice(), prod_1x_eval.as_slice()].concat();
|
||||
|
||||
let prod_x = DenseMultilinearExtension::from_evaluations_vec(num_vars + 1, eval);
|
||||
|
||||
end_timer!(start);
|
||||
Ok(prod_x)
|
||||
}
|
||||
|
||||
/// generate the zerocheck proof for the virtual polynomial
|
||||
/// prod(1, x) - prod(x, 0) * prod(x, 1) + alpha * (f(x) - prod(0, x) * g(x))
|
||||
///
|
||||
/// Returns proof and Q(x) for testing purpose.
|
||||
///
|
||||
/// Cost: O(N)
|
||||
pub(super) fn prove_zero_check<F: PrimeField>(
|
||||
fx: &DenseMultilinearExtension<F>,
|
||||
gx: &DenseMultilinearExtension<F>,
|
||||
prod_x: &DenseMultilinearExtension<F>,
|
||||
alpha: &F,
|
||||
transcript: &mut IOPTranscript<F>,
|
||||
) -> Result<(IOPProof<F>, VirtualPolynomial<F>), PolyIOPErrors> {
|
||||
let start = start_timer!(|| "zerocheck in product check");
|
||||
|
||||
let prod_partial_evals = build_prod_partial_eval(prod_x)?;
|
||||
let prod_0x = Rc::new(prod_partial_evals[0].clone());
|
||||
let prod_1x = Rc::new(prod_partial_evals[1].clone());
|
||||
let prod_x0 = Rc::new(prod_partial_evals[2].clone());
|
||||
let prod_x1 = Rc::new(prod_partial_evals[3].clone());
|
||||
let fx = Rc::new(fx.clone());
|
||||
let gx = Rc::new(gx.clone());
|
||||
|
||||
// compute g(x) * prod(0, x) * alpha
|
||||
let mut q_x = VirtualPolynomial::new_from_mle(gx, F::one());
|
||||
q_x.mul_by_mle(prod_0x, *alpha)?;
|
||||
|
||||
// g(x) * prod(0, x) * alpha
|
||||
// - f(x) * alpha
|
||||
q_x.add_mle_list([fx], -*alpha)?;
|
||||
|
||||
// Q(x) := prod(1,x) - prod(x, 0) * prod(x, 1)
|
||||
// + alpha * (
|
||||
// g(x) * prod(0, x)
|
||||
// - f(x))
|
||||
q_x.add_mle_list([prod_x0, prod_x1], -F::one())?;
|
||||
q_x.add_mle_list([prod_1x], F::one())?;
|
||||
|
||||
let iop_proof = <PolyIOP<F> as ZeroCheck<F>>::prove(&q_x, transcript)?;
|
||||
|
||||
end_timer!(start);
|
||||
Ok((iop_proof, q_x))
|
||||
}
|
||||
|
||||
/// Helper function of the IOP.
|
||||
///
|
||||
/// Input:
|
||||
/// - prod(x)
|
||||
///
|
||||
/// Output: the following 4 polynomials
|
||||
/// - prod(0, x)
|
||||
/// - prod(1, x)
|
||||
/// - prod(x, 0)
|
||||
/// - prod(x, 1)
|
||||
fn build_prod_partial_eval<F: PrimeField>(
|
||||
prod_x: &DenseMultilinearExtension<F>,
|
||||
) -> Result<[DenseMultilinearExtension<F>; 4], PolyIOPErrors> {
|
||||
let start = start_timer!(|| "build partial prod polynomial");
|
||||
|
||||
let prod_x_eval = &prod_x.evaluations;
|
||||
let num_vars = prod_x.num_vars - 1;
|
||||
|
||||
// prod(0, x)
|
||||
let prod_0_x =
|
||||
DenseMultilinearExtension::from_evaluations_slice(num_vars, &prod_x_eval[0..1 << num_vars]);
|
||||
// prod(1, x)
|
||||
let prod_1_x = DenseMultilinearExtension::from_evaluations_slice(
|
||||
num_vars,
|
||||
&prod_x_eval[1 << num_vars..1 << (num_vars + 1)],
|
||||
);
|
||||
|
||||
// ===================================
|
||||
// prod(x, 0) and prod(x, 1)
|
||||
// ===================================
|
||||
//
|
||||
// now we compute eval_x0 and eval_x1
|
||||
// eval_0x will be the odd coefficients of eval
|
||||
// and eval_1x will be the even coefficients of eval
|
||||
let mut eval_x0 = vec![];
|
||||
let mut eval_x1 = vec![];
|
||||
for (x, &prod_x) in prod_x_eval.iter().enumerate() {
|
||||
if x & 1 == 0 {
|
||||
eval_x0.push(prod_x);
|
||||
} else {
|
||||
eval_x1.push(prod_x);
|
||||
}
|
||||
}
|
||||
let prod_x_0 = DenseMultilinearExtension::from_evaluations_vec(num_vars, eval_x0);
|
||||
let prod_x_1 = DenseMultilinearExtension::from_evaluations_vec(num_vars, eval_x1);
|
||||
|
||||
end_timer!(start);
|
||||
|
||||
Ok([prod_0_x, prod_1_x, prod_x_0, prod_x_1])
|
||||
}
|
||||
|
||||
/// Returns the evaluations of
|
||||
/// - `prod(0,x) := prod(0, x1, …, xn)` which is the MLE over the
|
||||
/// evaluations of f(x)/g(x) on the boolean hypercube {0,1}^n:
|
||||
///
|
||||
/// The caller needs to check num_vars matches in f/g
|
||||
/// Cost: linear in N.
|
||||
fn compute_prod_0<F: PrimeField>(
|
||||
fx: &DenseMultilinearExtension<F>,
|
||||
gx: &DenseMultilinearExtension<F>,
|
||||
) -> Result<Vec<F>, PolyIOPErrors> {
|
||||
let start = start_timer!(|| "compute prod(0,x)");
|
||||
|
||||
let mut prod_0x_evals = vec![];
|
||||
for (&fi, &gi) in fx.iter().zip(gx.iter()) {
|
||||
prod_0x_evals.push(fi / gi);
|
||||
}
|
||||
|
||||
end_timer!(start);
|
||||
Ok(prod_0x_evals)
|
||||
}
|
||||
@@ -16,7 +16,7 @@ pub struct IOPProof<F: PrimeField> {
|
||||
|
||||
/// A message from the prover to the verifier at a given round
|
||||
/// is a list of evaluations.
|
||||
#[derive(Clone, Debug, Default, PartialEq, CanonicalSerialize)]
|
||||
#[derive(Clone, Debug, Default, PartialEq, Eq, CanonicalSerialize)]
|
||||
pub struct IOPProverMessage<F: PrimeField> {
|
||||
pub(crate) evaluations: Vec<F>,
|
||||
}
|
||||
|
||||
@@ -113,7 +113,7 @@ pub trait SumCheckVerifier<F: PrimeField> {
|
||||
|
||||
/// A SumCheckSubClaim is a claim generated by the verifier at the end of
|
||||
/// verification when it is convinced.
|
||||
#[derive(Clone, Debug, Default, PartialEq)]
|
||||
#[derive(Clone, Debug, Default, PartialEq, Eq)]
|
||||
pub struct SumCheckSubClaim<F: PrimeField> {
|
||||
/// the multi-dimensional point that this multilinear extension is evaluated
|
||||
/// to
|
||||
|
||||
Reference in New Issue
Block a user