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adds removes the unnessecary v commitment and opening
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@aleph-v
aleph-v committed Jun 17, 2024
1 parent fd567c1 commit 9e7be09
Showing 1 changed file with 2 additions and 37 deletions.
39 changes: 2 additions & 37 deletions jolt-core/src/subprotocols/grand_product_quarks.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -17,12 +17,10 @@ use thiserror::Error;
#[derive(CanonicalSerialize, CanonicalDeserialize)]
pub struct QuarkGrandProductProof<C: CommitmentScheme> {
sumcheck_proof: SumcheckInstanceProof<C::Field>,
v_commitment: Vec<C::Commitment>,
f_commitment: Vec<C::Commitment>,
claimed_eval_f_x_r: (Vec<C::Field>, Vec<C::Field>, C::BatchedProof),
claimed_eval_f_r_x: (Vec<C::Field>, Vec<C::Field>, C::BatchedProof),
sum_openings: C::BatchedProof,
v_opening_proof: C::BatchedProof,
num_vars: usize,
}
pub struct QuarkGrandProduct<F: JoltField> {
Expand Down Expand Up @@ -208,7 +206,6 @@ impl<C: CommitmentScheme> QuarkGrandProductProof<C> {
let mut f_polys = Vec::<DensePolynomial<C::Field>>::new();
let mut sumcheck_polys = Vec::<DensePolynomial<C::Field>>::new();
let mut products = Vec::<C::Field>::new();
let mut v_polys = Vec::<DensePolynomial<C::Field>>::new();

for v in leaves {
let v_polynomial = DensePolynomial::<C::Field>::new(v.to_vec());
Expand All @@ -218,16 +215,11 @@ impl<C: CommitmentScheme> QuarkGrandProductProof<C> {
sumcheck_polys.push(f_r_0);
sumcheck_polys.push(f_r_1);
products.push(p);
v_polys.push(v_polynomial);
}

// We bind to these polynomials
transcript.append_scalars(b"grand product claim", &products);
let v_commitment = C::batch_commit_polys(&v_polys, setup, BatchType::Big);
let f_commitment = C::batch_commit_polys(&f_polys, setup, BatchType::Big);
for v in v_commitment.iter() {
v.append_to_transcript(b"v commitment", transcript);
}
for f in f_commitment.iter() {
f.append_to_transcript(b"f commitment", transcript);
}
Expand All @@ -241,7 +233,7 @@ impl<C: CommitmentScheme> QuarkGrandProductProof<C> {

// Sample a constant to do a random linear combination to combine the sumchecks
let r_combination: Vec<C::Field> =
transcript.challenge_vector(b"for the random linear comb", v_polys.len());
transcript.challenge_vector(b"for the random linear comb", f_polys.len());

// We define a closure using vals[0] = eq(tau, x), vals[1] = f(1, x), vals[1] = f(x, 0), vals[2] = f(x, 1)
let output_check_fn = |vals: &[C::Field]| -> C::Field {
Expand All @@ -268,7 +260,6 @@ impl<C: CommitmentScheme> QuarkGrandProductProof<C> {

// Interface for the batch proof is &[&Poly] but we have &[Poly]
let borrowed_f: Vec<&DensePolynomial<C::Field>> = f_polys.iter().collect();
let borrowed_v: Vec<&DensePolynomial<C::Field>> = v_polys.iter().collect();

// Do the line reduction open and prove on r
let claimed_eval_f_x_r = open_and_prove::<C>(&x, false, &f_polys, setup, transcript);
Expand All @@ -286,26 +277,15 @@ impl<C: CommitmentScheme> QuarkGrandProductProof<C> {
transcript,
);

// Here we don't calculate an eval because it should be equal to f(0, x) which is the first point we open
let v_opening_proof = C::batch_prove(
setup,
&borrowed_v,
&x,
&claimed_eval_f_x_r.0,
BatchType::Big,
transcript,
);
let num_vars = v_variables;

(
Self {
sumcheck_proof,
v_commitment,
f_commitment,
claimed_eval_f_x_r,
claimed_eval_f_r_x,
sum_openings,
v_opening_proof,
num_vars,
},
x.clone(),
Expand All @@ -323,17 +303,14 @@ impl<C: CommitmentScheme> QuarkGrandProductProof<C> {
) -> Result<(Vec<C::Field>, Vec<C::Field>), QuarkError> {
// First we append the claimed values for the commitment and the product
transcript.append_scalars(b"grand product claim", claims);
for v in self.v_commitment.iter() {
v.append_to_transcript(b"v commitment", transcript);
}
for f in self.f_commitment.iter() {
f.append_to_transcript(b"f commitment", transcript);
}

//Next sample the tau and construct the evals poly
let tau: Vec<C::Field> = transcript.challenge_vector(b"element for eval poly", n_rounds);
let r_combination: Vec<C::Field> =
transcript.challenge_vector(b"for the random linear comb", self.v_commitment.len());
transcript.challenge_vector(b"for the random linear comb", self.f_commitment.len());

// To complete the sumcheck proof we have to validate that our polynomial openings match and are right.
let (expected, r) = self
Expand All @@ -343,7 +320,6 @@ impl<C: CommitmentScheme> QuarkGrandProductProof<C> {

// Again the batch verify expects we have a slice of borrows but we have a slice of Commitments
let borrowed_f: Vec<&C::Commitment> = self.f_commitment.iter().collect();
let borrowed_v: Vec<&C::Commitment> = self.v_commitment.iter().collect();

// We apply the protocol for line reduced openings to prove f(0r) f(1r) and f(r1) f(r0)
line_reduce_opening_verify::<C>(
Expand Down Expand Up @@ -380,17 +356,6 @@ impl<C: CommitmentScheme> QuarkGrandProductProof<C> {
)
.map_err(|_| QuarkError::InvalidOpeningProof)?;

// Now we enforce that f(0, r) = v(r) via an opening proof on v
C::batch_verify(
&self.v_opening_proof,
setup,
&r,
&self.claimed_eval_f_x_r.0,
&borrowed_v,
transcript,
)
.map_err(|_| QuarkError::InvalidOpeningProof)?;

// Use the log(n) form to calculate eq(tau, r)
let eq_eval: C::Field = r
.iter()
Expand Down

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