From 9d1ede111bdc297ccc43870b417d7a4805a20522 Mon Sep 17 00:00:00 2001
From: "a.stevan" <antoine.stevan@isae-supaero.fr>
Date: Fri, 19 Jan 2024 11:28:42 +0100
Subject: [PATCH 1/8] global vector
---
src/lib.rs | 48 +++++++++++++++++++++++++-----------------------
1 file changed, 25 insertions(+), 23 deletions(-)
diff --git a/src/lib.rs b/src/lib.rs
index 7e416931..f36f6865 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -112,31 +112,33 @@ where
{
let k = polynomials[0].coeffs().len();
- let evaluations = points
+ Ok(points
.iter()
- .map(|point| polynomials.iter().map(|p| p.evaluate(point)).collect())
- .collect::<Vec<Vec<E::ScalarField>>>();
-
- let mut proofs = Vec::new();
- for (i, row) in evaluations.iter().enumerate() {
- let mut linear_combination = Vec::new();
- linear_combination.resize(i + 1, E::ScalarField::zero());
- linear_combination[i] = E::ScalarField::one();
-
- proofs.push(Block {
- shard: fec::Shard {
- k: k as u32,
- linear_combination,
- hash: hash.to_vec(),
- bytes: row.clone(),
- size: nb_bytes,
- },
- commit: commits.clone(),
- m: polynomials.len(),
- })
- }
+ .map(|point| {
+ let eval = polynomials
+ .iter()
+ .map(|p| p.evaluate(point))
+ .collect::<Vec<_>>();
- Ok(proofs)
+ let mut linear_combination = Vec::new();
+ linear_combination.push(E::ScalarField::one());
+ for i in 1..k {
+ linear_combination.push(linear_combination[i - 1].mul(point));
+ }
+
+ Block {
+ shard: fec::Shard {
+ k: k as u32,
+ linear_combination,
+ hash: hash.to_vec(),
+ bytes: eval.clone(),
+ size: nb_bytes,
+ },
+ commit: commits.clone(),
+ m: polynomials.len(),
+ }
+ })
+ .collect::<Vec<_>>())
}
pub fn encode<E, P>(
--
GitLab
From 48706cf16fa2557485ca4bcf844103fcfb96155e Mon Sep 17 00:00:00 2001
From: "a.stevan" <antoine.stevan@isae-supaero.fr>
Date: Fri, 19 Jan 2024 11:31:46 +0100
Subject: [PATCH 2/8] fix verify
---
src/lib.rs | 18 +-----------------
1 file changed, 1 insertion(+), 17 deletions(-)
diff --git a/src/lib.rs b/src/lib.rs
index f36f6865..563cb987 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -260,23 +260,7 @@ where
.linear_combination
.iter()
.enumerate()
- .map(|(i, w)| {
- // NOTE: this is where we implicitely compute the Vandermonde matrix
- // hence, the sum of commits is indeed the sum of the encoded n shards
- // and not the original k source shards.
- let alpha = E::ScalarField::from_le_bytes_mod_order(&i.to_le_bytes());
-
- let f: E::G1 = block
- .commit
- .iter()
- .enumerate()
- .map(|(j, c)| {
- let commit: E::G1 = c.0.into();
- commit.mul(alpha.pow([j as u64]))
- })
- .sum();
- f * w
- })
+ .map(|(i, w)| Into::<E::G1>::into(block.commit[i].0) * w)
.sum();
Ok(Into::<E::G1>::into(commit.0) == rhs)
}
--
GitLab
From 88bee6530da127d9b682a9ad22e3c015bb5fd4f5 Mon Sep 17 00:00:00 2001
From: "a.stevan" <antoine.stevan@isae-supaero.fr>
Date: Fri, 19 Jan 2024 11:32:05 +0100
Subject: [PATCH 3/8] remove unused imports
---
src/lib.rs | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/src/lib.rs b/src/lib.rs
index 563cb987..837d2a90 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,7 +1,7 @@
use std::ops::{Div, Mul};
use ark_ec::pairing::Pairing;
-use ark_ff::{Field, PrimeField};
+use ark_ff::PrimeField;
use ark_poly::DenseUVPolynomial;
use ark_poly_commit::kzg10::{Commitment, Powers, Randomness, KZG10};
use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
--
GitLab
From 6c61e86614fa67f1bbbcade07115ec2cd428f305 Mon Sep 17 00:00:00 2001
From: "a.stevan" <antoine.stevan@isae-supaero.fr>
Date: Fri, 19 Jan 2024 11:36:30 +0100
Subject: [PATCH 4/8] fix fec::decode
---
src/fec.rs | 35 ++++++-----------------------------
1 file changed, 6 insertions(+), 29 deletions(-)
diff --git a/src/fec.rs b/src/fec.rs
index 3c231564..122dfa7a 100644
--- a/src/fec.rs
+++ b/src/fec.rs
@@ -65,33 +65,14 @@ pub fn decode<E: Pairing>(blocks: Vec<Shard<E>>, transpose: bool) -> Result<Vec<
return Err(KomodoError::TooFewShards(np, k as usize));
}
- let n = 1 + blocks
- .iter()
- .flat_map(|b| {
- b.linear_combination
- .iter()
- .enumerate()
- .filter(|(_, l)| !l.is_zero())
- .map(|(i, _)| i)
- .collect::<Vec<_>>()
- })
- .max()
- .unwrap_or_default();
- let points: Vec<E::ScalarField> = (0..n)
- .map(|i| E::ScalarField::from_le_bytes_mod_order(&i.to_le_bytes()))
- .collect();
- let encoding_mat = Matrix::vandermonde(&points, k as usize);
-
- let lin_comb_mat = Matrix::from_vec_vec(
+ let encoding_mat = Matrix::from_vec_vec(
blocks
.iter()
- .map(|b| {
- let mut comb = b.linear_combination.clone();
- comb.resize(n, E::ScalarField::zero());
- comb
- })
+ .map(|b| b.linear_combination.clone())
.collect(),
- )?;
+ )?
+ .transpose()
+ .truncate(None, Some(np - k as usize));
let shards = Matrix::from_vec_vec(
blocks
@@ -102,11 +83,7 @@ pub fn decode<E: Pairing>(blocks: Vec<Shard<E>>, transpose: bool) -> Result<Vec<
)?
.transpose();
- let ra = encoding_mat
- .mul(&lin_comb_mat.transpose())?
- .truncate(None, Some(np - k as usize));
-
- let source_shards = shards.mul(&ra.invert()?)?;
+ let source_shards = shards.mul(&encoding_mat.invert()?)?;
let source_shards = if transpose {
source_shards.transpose().elements
} else {
--
GitLab
From 16e5765b3b2b35cf08c398fae99e4d8712c2583d Mon Sep 17 00:00:00 2001
From: "a.stevan" <antoine.stevan@isae-supaero.fr>
Date: Fri, 19 Jan 2024 11:39:35 +0100
Subject: [PATCH 5/8] fix FEC decoding tests
---
src/fec.rs | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/src/fec.rs b/src/fec.rs
index 122dfa7a..be205ca5 100644
--- a/src/fec.rs
+++ b/src/fec.rs
@@ -2,7 +2,6 @@ use std::cmp::max;
use std::ops::{Add, Mul};
use ark_ec::pairing::Pairing;
-use ark_ff::PrimeField;
use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
use ark_std::Zero;
@@ -97,6 +96,8 @@ pub fn decode<E: Pairing>(blocks: Vec<Shard<E>>, transpose: bool) -> Result<Vec<
#[cfg(test)]
mod tests {
+ use std::ops::Mul;
+
use ark_bls12_381::Bls12_381;
use ark_ec::pairing::Pairing;
use ark_ff::PrimeField;
@@ -140,9 +141,12 @@ mod tests {
.chunks(source_shards.height)
.enumerate()
.map(|(i, s)| {
+ let alpha = E::ScalarField::from_le_bytes_mod_order(&i.to_le_bytes());
let mut linear_combination = Vec::new();
- linear_combination.resize(i + 1, E::ScalarField::zero());
- linear_combination[i] = E::ScalarField::one();
+ linear_combination.push(E::ScalarField::one());
+ for i in 1..k {
+ linear_combination.push(linear_combination[i - 1].mul(alpha));
+ }
Shard {
k: k as u32,
--
GitLab
From 4c3f851f9bf5d0ec01abb6bbbaea52cc797c18d6 Mon Sep 17 00:00:00 2001
From: "a.stevan" <antoine.stevan@isae-supaero.fr>
Date: Fri, 19 Jan 2024 13:32:02 +0100
Subject: [PATCH 6/8] mark `Matrix::vandermonde` as "dead code"
---
src/linalg.rs | 1 +
1 file changed, 1 insertion(+)
diff --git a/src/linalg.rs b/src/linalg.rs
index 8a0c527d..222b1baa 100644
--- a/src/linalg.rs
+++ b/src/linalg.rs
@@ -30,6 +30,7 @@ impl<T: Field> Matrix<T> {
Self::from_diagonal(vec![T::one(); size])
}
+ #[allow(dead_code)]
pub(super) fn vandermonde(points: &[T], height: usize) -> Self {
let width = points.len();
--
GitLab
From 01dd77d89b157966574e9a25cbf8f9977d0da720 Mon Sep 17 00:00:00 2001
From: "a.stevan" <antoine.stevan@isae-supaero.fr>
Date: Fri, 19 Jan 2024 15:02:34 +0100
Subject: [PATCH 7/8] combine shards with length k
---
src/fec.rs | 26 +++++++++++---------------
1 file changed, 11 insertions(+), 15 deletions(-)
diff --git a/src/fec.rs b/src/fec.rs
index be205ca5..2ae67e23 100644
--- a/src/fec.rs
+++ b/src/fec.rs
@@ -1,4 +1,3 @@
-use std::cmp::max;
use std::ops::{Add, Mul};
use ark_ec::pairing::Pairing;
@@ -27,18 +26,14 @@ impl<E: Pairing> Shard<E> {
}
let mut linear_combination = Vec::new();
- linear_combination.resize(
- max(
- self.linear_combination.len(),
- other.linear_combination.len(),
- ),
- E::ScalarField::zero(),
- );
- for (i, l) in self.linear_combination.iter().enumerate() {
- linear_combination[i] += l.mul(alpha);
- }
- for (i, l) in other.linear_combination.iter().enumerate() {
- linear_combination[i] += l.mul(beta);
+ linear_combination.resize(self.k as usize, E::ScalarField::zero());
+ for (i, (l, r)) in self
+ .linear_combination
+ .iter()
+ .zip(other.linear_combination.iter())
+ .enumerate()
+ {
+ linear_combination[i] = l.mul(alpha) + r.mul(beta);
}
Shard {
@@ -212,7 +207,7 @@ mod tests {
) -> Shard<E> {
let bytes = field::split_data_into_field_elements::<E>(bytes, 1);
Shard {
- k: 0,
+ k: 2,
linear_combination: linear_combination.to_vec(),
hash: vec![],
bytes,
@@ -221,7 +216,8 @@ mod tests {
}
fn recoding_template<E: Pairing>() {
- let a: Shard<E> = create_fake_shard(&[E::ScalarField::one()], &[1, 2, 3]);
+ let a: Shard<E> =
+ create_fake_shard(&[E::ScalarField::one(), E::ScalarField::zero()], &[1, 2, 3]);
let b: Shard<E> =
create_fake_shard(&[E::ScalarField::zero(), E::ScalarField::one()], &[4, 5, 6]);
--
GitLab
From 61a19739f76c95137ec951fe66099ad5eaccd797 Mon Sep 17 00:00:00 2001
From: "a.stevan" <antoine.stevan@isae-supaero.fr>
Date: Fri, 19 Jan 2024 15:15:54 +0100
Subject: [PATCH 8/8] compute the linear combination directly
---
src/fec.rs | 18 ++++++------------
1 file changed, 6 insertions(+), 12 deletions(-)
diff --git a/src/fec.rs b/src/fec.rs
index 2ae67e23..20129c98 100644
--- a/src/fec.rs
+++ b/src/fec.rs
@@ -25,20 +25,14 @@ impl<E: Pairing> Shard<E> {
return self.clone();
}
- let mut linear_combination = Vec::new();
- linear_combination.resize(self.k as usize, E::ScalarField::zero());
- for (i, (l, r)) in self
- .linear_combination
- .iter()
- .zip(other.linear_combination.iter())
- .enumerate()
- {
- linear_combination[i] = l.mul(alpha) + r.mul(beta);
- }
-
Shard {
k: self.k,
- linear_combination,
+ linear_combination: self
+ .linear_combination
+ .iter()
+ .zip(other.linear_combination.iter())
+ .map(|(l, r)| l.mul(alpha) + r.mul(beta))
+ .collect(),
hash: self.hash.clone(),
bytes: self
.bytes
--
GitLab