Smash out monero-bulletproofs

Removes usage of dalek-ff-group/multiexp for curve25519-dalek.

Makes compiling in the generators an optional feature.

Adds a structured batch verifier which should be notably more performant.

Documentation and clean up still necessary.

coins/monero/ringct/bulletproofs/src/batch_verifier.rs

@@ -0,0 +1,94 @@
+use curve25519_dalek::{
+  constants::ED25519_BASEPOINT_POINT,
+  traits::{IsIdentity, VartimeMultiscalarMul},
+  scalar::Scalar,
+  edwards::EdwardsPoint,
+};
+
+use monero_generators::{H, Generators};
+
+use crate::{original, plus};
+
+#[derive(Default)]
+pub(crate) struct InternalBatchVerifier {
+  pub(crate) g: Scalar,
+  pub(crate) h: Scalar,
+  pub(crate) g_bold: Vec<Scalar>,
+  pub(crate) h_bold: Vec<Scalar>,
+  pub(crate) other: Vec<(Scalar, EdwardsPoint)>,
+}
+
+impl InternalBatchVerifier {
+  pub fn new() -> Self {
+    Self { g: Scalar::ZERO, h: Scalar::ZERO, g_bold: vec![], h_bold: vec![], other: vec![] }
+  }
+
+  #[must_use]
+  pub fn verify(self, G: EdwardsPoint, H: EdwardsPoint, generators: &Generators) -> bool {
+    let capacity = 2 + self.g_bold.len() + self.h_bold.len() + self.other.len();
+    let mut scalars = Vec::with_capacity(capacity);
+    let mut points = Vec::with_capacity(capacity);
+
+    scalars.push(self.g);
+    points.push(G);
+
+    scalars.push(self.h);
+    points.push(H);
+
+    for (i, g_bold) in self.g_bold.into_iter().enumerate() {
+      scalars.push(g_bold);
+      points.push(generators.G[i]);
+    }
+
+    for (i, h_bold) in self.h_bold.into_iter().enumerate() {
+      scalars.push(h_bold);
+      points.push(generators.H[i]);
+    }
+
+    for (scalar, point) in self.other {
+      scalars.push(scalar);
+      points.push(point);
+    }
+
+    EdwardsPoint::vartime_multiscalar_mul(scalars, points).is_identity()
+  }
+}
+
+#[derive(Default)]
+pub(crate) struct BulletproofsBatchVerifier(pub(crate) InternalBatchVerifier);
+impl BulletproofsBatchVerifier {
+  #[must_use]
+  pub fn verify(self) -> bool {
+    self.0.verify(ED25519_BASEPOINT_POINT, H(), original::GENERATORS())
+  }
+}
+
+#[derive(Default)]
+pub(crate) struct BulletproofsPlusBatchVerifier(pub(crate) InternalBatchVerifier);
+impl BulletproofsPlusBatchVerifier {
+  #[must_use]
+  pub fn verify(self) -> bool {
+    // Bulletproofs+ is written as per the paper, with G for the value and H for the mask
+    // Monero uses H for the value and G for the mask
+    self.0.verify(H(), ED25519_BASEPOINT_POINT, plus::GENERATORS())
+  }
+}
+
+#[derive(Default)]
+pub struct BatchVerifier {
+  pub(crate) original: BulletproofsBatchVerifier,
+  pub(crate) plus: BulletproofsPlusBatchVerifier,
+}
+impl BatchVerifier {
+  pub fn new() -> Self {
+    Self {
+      original: BulletproofsBatchVerifier(InternalBatchVerifier::new()),
+      plus: BulletproofsPlusBatchVerifier(InternalBatchVerifier::new()),
+    }
+  }
+
+  #[must_use]
+  pub fn verify(self) -> bool {
+    self.original.verify() && self.plus.verify()
+  }
+}

coins/monero/ringct/bulletproofs/src/core.rs

@@ -0,0 +1,153 @@
+use std_shims::{vec::Vec, sync::OnceLock};
+
+use rand_core::{RngCore, CryptoRng};
+use subtle::{Choice, ConditionallySelectable};
+
+use curve25519_dalek::{
+  constants::ED25519_BASEPOINT_TABLE,
+  traits::{MultiscalarMul, VartimeMultiscalarMul},
+  scalar::Scalar,
+  edwards::EdwardsPoint,
+};
+
+pub(crate) use monero_generators::Generators;
+use monero_primitives::{INV_EIGHT, Commitment, keccak256_to_scalar};
+
+pub(crate) use crate::scalar_vector::*;
+
+// Components common between variants
+// TODO: Move to generators? primitives?
+pub(crate) const MAX_M: usize = 16;
+pub(crate) const LOG_N: usize = 6; // 2 << 6 == N
+pub(crate) const N: usize = 64;
+
+pub(crate) fn multiexp(pairs: &[(Scalar, EdwardsPoint)]) -> EdwardsPoint {
+  let mut buf_scalars = Vec::with_capacity(pairs.len());
+  let mut buf_points = Vec::with_capacity(pairs.len());
+  for (scalar, point) in pairs {
+    buf_scalars.push(scalar);
+    buf_points.push(point);
+  }
+  EdwardsPoint::multiscalar_mul(buf_scalars, buf_points)
+}
+
+pub(crate) fn multiexp_vartime(pairs: &[(Scalar, EdwardsPoint)]) -> EdwardsPoint {
+  let mut buf_scalars = Vec::with_capacity(pairs.len());
+  let mut buf_points = Vec::with_capacity(pairs.len());
+  for (scalar, point) in pairs {
+    buf_scalars.push(scalar);
+    buf_points.push(point);
+  }
+  EdwardsPoint::vartime_multiscalar_mul(buf_scalars, buf_points)
+}
+
+pub(crate) fn vector_exponent(
+  generators: &Generators,
+  a: &ScalarVector,
+  b: &ScalarVector,
+) -> EdwardsPoint {
+  debug_assert_eq!(a.len(), b.len());
+  (a * &generators.G[.. a.len()]) + (b * &generators.H[.. b.len()])
+}
+
+pub(crate) fn hash_cache(cache: &mut Scalar, mash: &[[u8; 32]]) -> Scalar {
+  let slice =
+    &[cache.to_bytes().as_ref(), mash.iter().copied().flatten().collect::<Vec<_>>().as_ref()]
+      .concat();
+  *cache = keccak256_to_scalar(slice);
+  *cache
+}
+
+pub(crate) fn MN(outputs: usize) -> (usize, usize, usize) {
+  let mut logM = 0;
+  let mut M;
+  while {
+    M = 1 << logM;
+    (M <= MAX_M) && (M < outputs)
+  } {
+    logM += 1;
+  }
+
+  (logM + LOG_N, M, M * N)
+}
+
+pub(crate) fn bit_decompose(commitments: &[Commitment]) -> (ScalarVector, ScalarVector) {
+  let (_, M, MN) = MN(commitments.len());
+
+  let sv = commitments.iter().map(|c| Scalar::from(c.amount)).collect::<Vec<_>>();
+  let mut aL = ScalarVector::new(MN);
+  let mut aR = ScalarVector::new(MN);
+
+  for j in 0 .. M {
+    for i in (0 .. N).rev() {
+      let bit =
+        if j < sv.len() { Choice::from((sv[j][i / 8] >> (i % 8)) & 1) } else { Choice::from(0) };
+      aL.0[(j * N) + i] = Scalar::conditional_select(&Scalar::ZERO, &Scalar::ONE, bit);
+      aR.0[(j * N) + i] = Scalar::conditional_select(&-Scalar::ONE, &Scalar::ZERO, bit);
+    }
+  }
+
+  (aL, aR)
+}
+
+pub(crate) fn hash_commitments<C: IntoIterator<Item = EdwardsPoint>>(
+  commitments: C,
+) -> (Scalar, Vec<EdwardsPoint>) {
+  let V = commitments.into_iter().map(|c| c * INV_EIGHT()).collect::<Vec<_>>();
+  (keccak256_to_scalar(V.iter().flat_map(|V| V.compress().to_bytes()).collect::<Vec<_>>()), V)
+}
+
+pub(crate) fn alpha_rho<R: RngCore + CryptoRng>(
+  rng: &mut R,
+  generators: &Generators,
+  aL: &ScalarVector,
+  aR: &ScalarVector,
+) -> (Scalar, EdwardsPoint) {
+  let ar = Scalar::random(rng);
+  (ar, (vector_exponent(generators, aL, aR) + (ED25519_BASEPOINT_TABLE * &ar)) * INV_EIGHT())
+}
+
+pub(crate) fn LR_statements(
+  a: &ScalarVector,
+  G_i: &[EdwardsPoint],
+  b: &ScalarVector,
+  H_i: &[EdwardsPoint],
+  cL: Scalar,
+  U: EdwardsPoint,
+) -> Vec<(Scalar, EdwardsPoint)> {
+  let mut res = a
+    .0
+    .iter()
+    .copied()
+    .zip(G_i.iter().copied())
+    .chain(b.0.iter().copied().zip(H_i.iter().copied()))
+    .collect::<Vec<_>>();
+  res.push((cL, U));
+  res
+}
+
+static TWO_N_CELL: OnceLock<ScalarVector> = OnceLock::new();
+pub(crate) fn TWO_N() -> &'static ScalarVector {
+  TWO_N_CELL.get_or_init(|| ScalarVector::powers(Scalar::from(2u8), N))
+}
+
+pub(crate) fn challenge_products(w: &[Scalar], winv: &[Scalar]) -> Vec<Scalar> {
+  let mut products = vec![Scalar::ZERO; 1 << w.len()];
+  products[0] = winv[0];
+  products[1] = w[0];
+  for j in 1 .. w.len() {
+    let mut slots = (1 << (j + 1)) - 1;
+    while slots > 0 {
+      products[slots] = products[slots / 2] * w[j];
+      products[slots - 1] = products[slots / 2] * winv[j];
+      slots = slots.saturating_sub(2);
+    }
+  }
+
+  // Sanity check as if the above failed to populate, it'd be critical
+  for w in &products {
+    debug_assert!(*w != Scalar::ZERO);
+  }
+
+  products
+}

coins/monero/ringct/bulletproofs/src/lib.rs

@@ -0,0 +1,247 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+#![cfg_attr(not(feature = "std"), no_std)]
+#![allow(non_snake_case)]
+
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
+};
+
+use rand_core::{RngCore, CryptoRng};
+use zeroize::Zeroizing;
+
+use curve25519_dalek::edwards::EdwardsPoint;
+
+use monero_io::*;
+use monero_primitives::Commitment;
+
+pub(crate) mod scalar_vector;
+pub(crate) mod core;
+use crate::core::LOG_N;
+
+pub mod batch_verifier;
+use batch_verifier::{InternalBatchVerifier, BulletproofsPlusBatchVerifier, BatchVerifier};
+
+pub(crate) mod original;
+use crate::original::OriginalStruct;
+
+pub(crate) mod plus;
+use crate::plus::*;
+
+#[cfg(test)]
+mod tests;
+
+pub const MAX_COMMITMENTS: usize = crate::core::MAX_M;
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+#[cfg_attr(feature = "std", derive(thiserror::Error))]
+pub enum BulletproofError {
+  #[cfg_attr(feature = "std", error("no commitments to prove the range for"))]
+  NoCommitments,
+  #[cfg_attr(feature = "std", error("too many commitments to prove the range for"))]
+  TooManyCommitments,
+}
+
+/// Bulletproof enum, encapsulating both Bulletproofs and Bulletproofs+.
+#[allow(clippy::large_enum_variant)]
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub enum Bulletproof {
+  Original(OriginalStruct),
+  Plus(AggregateRangeProof),
+}
+
+impl Bulletproof {
+  fn bp_fields(plus: bool) -> usize {
+    if plus {
+      6
+    } else {
+      9
+    }
+  }
+
+  // https://github.com/monero-project/monero/blob/94e67bf96bbc010241f29ada6abc89f49a81759c/
+  //   src/cryptonote_basic/cryptonote_format_utils.cpp#L106-L124
+  pub fn calculate_bp_clawback(plus: bool, n_outputs: usize) -> (usize, usize) {
+    #[allow(non_snake_case)]
+    let mut LR_len = 0;
+    let mut n_padded_outputs = 1;
+    while n_padded_outputs < n_outputs {
+      LR_len += 1;
+      n_padded_outputs = 1 << LR_len;
+    }
+    LR_len += LOG_N;
+
+    let mut bp_clawback = 0;
+    if n_padded_outputs > 2 {
+      let fields = Bulletproof::bp_fields(plus);
+      let base = ((fields + (2 * (LOG_N + 1))) * 32) / 2;
+      let size = (fields + (2 * LR_len)) * 32;
+      bp_clawback = ((base * n_padded_outputs) - size) * 4 / 5;
+    }
+
+    (bp_clawback, LR_len)
+  }
+
+  pub fn fee_weight(plus: bool, outputs: usize) -> usize {
+    #[allow(non_snake_case)]
+    let (bp_clawback, LR_len) = Bulletproof::calculate_bp_clawback(plus, outputs);
+    32 * (Bulletproof::bp_fields(plus) + (2 * LR_len)) + 2 + bp_clawback
+  }
+
+  /// Prove the list of commitments are within [0 .. 2^64) with an aggregate Bulletproof.
+  pub fn prove<R: RngCore + CryptoRng>(
+    rng: &mut R,
+    outputs: &[Commitment],
+  ) -> Result<Bulletproof, BulletproofError> {
+    if outputs.is_empty() {
+      Err(BulletproofError::NoCommitments)?;
+    }
+    if outputs.len() > MAX_COMMITMENTS {
+      Err(BulletproofError::TooManyCommitments)?;
+    }
+    Ok(Bulletproof::Original(OriginalStruct::prove(rng, outputs)))
+  }
+
+  /// Prove the list of commitments are within [0 .. 2^64) with an aggregate Bulletproof+.
+  pub fn prove_plus<R: RngCore + CryptoRng>(
+    rng: &mut R,
+    outputs: Vec<Commitment>,
+  ) -> Result<Bulletproof, BulletproofError> {
+    if outputs.is_empty() {
+      Err(BulletproofError::NoCommitments)?;
+    }
+    if outputs.len() > MAX_COMMITMENTS {
+      Err(BulletproofError::TooManyCommitments)?;
+    }
+    Ok(Bulletproof::Plus(
+      AggregateRangeStatement::new(outputs.iter().map(Commitment::calculate).collect())
+        .unwrap()
+        .prove(rng, &Zeroizing::new(AggregateRangeWitness::new(outputs).unwrap()))
+        .unwrap(),
+    ))
+  }
+
+  /// Verify the given Bulletproof(+).
+  #[must_use]
+  pub fn verify<R: RngCore + CryptoRng>(&self, rng: &mut R, commitments: &[EdwardsPoint]) -> bool {
+    match self {
+      Bulletproof::Original(bp) => bp.verify(rng, commitments),
+      Bulletproof::Plus(bp) => {
+        let mut verifier = BulletproofsPlusBatchVerifier(InternalBatchVerifier::new());
+        let Some(statement) = AggregateRangeStatement::new(commitments.to_vec()) else {
+          return false;
+        };
+        if !statement.verify(rng, &mut verifier, bp.clone()) {
+          return false;
+        }
+        verifier.verify()
+      }
+    }
+  }
+
+  /// Accumulate the verification for the given Bulletproof into the specified BatchVerifier.
+  ///
+  /// Returns false if the Bulletproof isn't sane, leaving the BatchVerifier in an undefined
+  /// state.
+  /// Returns true if the Bulletproof is sane, regardless of their validity.
+  #[must_use]
+  pub fn batch_verify<R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    verifier: &mut BatchVerifier,
+    commitments: &[EdwardsPoint],
+  ) -> bool {
+    match self {
+      Bulletproof::Original(bp) => bp.batch_verify(rng, &mut verifier.original, commitments),
+      Bulletproof::Plus(bp) => {
+        let Some(statement) = AggregateRangeStatement::new(commitments.to_vec()) else {
+          return false;
+        };
+        statement.verify(rng, &mut verifier.plus, bp.clone())
+      }
+    }
+  }
+
+  fn write_core<W: Write, F: Fn(&[EdwardsPoint], &mut W) -> io::Result<()>>(
+    &self,
+    w: &mut W,
+    specific_write_vec: F,
+  ) -> io::Result<()> {
+    match self {
+      Bulletproof::Original(bp) => {
+        write_point(&bp.A, w)?;
+        write_point(&bp.S, w)?;
+        write_point(&bp.T1, w)?;
+        write_point(&bp.T2, w)?;
+        write_scalar(&bp.tau_x, w)?;
+        write_scalar(&bp.mu, w)?;
+        specific_write_vec(&bp.L, w)?;
+        specific_write_vec(&bp.R, w)?;
+        write_scalar(&bp.a, w)?;
+        write_scalar(&bp.b, w)?;
+        write_scalar(&bp.t, w)
+      }
+
+      Bulletproof::Plus(bp) => {
+        write_point(&bp.A, w)?;
+        write_point(&bp.wip.A, w)?;
+        write_point(&bp.wip.B, w)?;
+        write_scalar(&bp.wip.r_answer, w)?;
+        write_scalar(&bp.wip.s_answer, w)?;
+        write_scalar(&bp.wip.delta_answer, w)?;
+        specific_write_vec(&bp.wip.L, w)?;
+        specific_write_vec(&bp.wip.R, w)
+      }
+    }
+  }
+
+  pub fn signature_write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.write_core(w, |points, w| write_raw_vec(write_point, points, w))
+  }
+
+  /// Write the Bulletproof(+) to a writer.
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.write_core(w, |points, w| write_vec(write_point, points, w))
+  }
+
+  /// Serialize the Bulletproof(+) to a `Vec<u8>`.
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = vec![];
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  /// Read a Bulletproof.
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Bulletproof> {
+    Ok(Bulletproof::Original(OriginalStruct {
+      A: read_point(r)?,
+      S: read_point(r)?,
+      T1: read_point(r)?,
+      T2: read_point(r)?,
+      tau_x: read_scalar(r)?,
+      mu: read_scalar(r)?,
+      L: read_vec(read_point, r)?,
+      R: read_vec(read_point, r)?,
+      a: read_scalar(r)?,
+      b: read_scalar(r)?,
+      t: read_scalar(r)?,
+    }))
+  }
+
+  /// Read a Bulletproof+.
+  pub fn read_plus<R: Read>(r: &mut R) -> io::Result<Bulletproof> {
+    Ok(Bulletproof::Plus(AggregateRangeProof {
+      A: read_point(r)?,
+      wip: WipProof {
+        A: read_point(r)?,
+        B: read_point(r)?,
+        r_answer: read_scalar(r)?,
+        s_answer: read_scalar(r)?,
+        delta_answer: read_scalar(r)?,
+        L: read_vec(read_point, r)?.into_iter().collect(),
+        R: read_vec(read_point, r)?.into_iter().collect(),
+      },
+    }))
+  }
+}

coins/monero/ringct/bulletproofs/src/original.rs

@@ -0,0 +1,320 @@
+use std_shims::{vec::Vec, sync::OnceLock};
+
+use rand_core::{RngCore, CryptoRng};
+use zeroize::Zeroize;
+
+use curve25519_dalek::{constants::ED25519_BASEPOINT_POINT, scalar::Scalar, edwards::EdwardsPoint};
+
+use monero_generators::H;
+use monero_primitives::{INV_EIGHT, Commitment, keccak256_to_scalar};
+
+use crate::{
+  core::*,
+  batch_verifier::{InternalBatchVerifier, BulletproofsBatchVerifier},
+};
+
+include!(concat!(env!("OUT_DIR"), "/generators.rs"));
+
+static IP12_CELL: OnceLock<Scalar> = OnceLock::new();
+pub(crate) fn IP12() -> Scalar {
+  *IP12_CELL.get_or_init(|| ScalarVector(vec![Scalar::ONE; N]).inner_product(TWO_N()))
+}
+
+pub(crate) fn hadamard_fold(
+  l: &[EdwardsPoint],
+  r: &[EdwardsPoint],
+  a: Scalar,
+  b: Scalar,
+) -> Vec<EdwardsPoint> {
+  let mut res = Vec::with_capacity(l.len() / 2);
+  for i in 0 .. l.len() {
+    res.push(multiexp(&[(a, l[i]), (b, r[i])]));
+  }
+  res
+}
+
+/// Internal structure representing a Bulletproof.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct OriginalStruct {
+  pub(crate) A: EdwardsPoint,
+  pub(crate) S: EdwardsPoint,
+  pub(crate) T1: EdwardsPoint,
+  pub(crate) T2: EdwardsPoint,
+  pub(crate) tau_x: Scalar,
+  pub(crate) mu: Scalar,
+  pub(crate) L: Vec<EdwardsPoint>,
+  pub(crate) R: Vec<EdwardsPoint>,
+  pub(crate) a: Scalar,
+  pub(crate) b: Scalar,
+  pub(crate) t: Scalar,
+}
+
+impl OriginalStruct {
+  pub(crate) fn prove<R: RngCore + CryptoRng>(
+    rng: &mut R,
+    commitments: &[Commitment],
+  ) -> OriginalStruct {
+    let (logMN, M, MN) = MN(commitments.len());
+
+    let (aL, aR) = bit_decompose(commitments);
+    let commitments_points = commitments.iter().map(Commitment::calculate).collect::<Vec<_>>();
+    let (mut cache, _) = hash_commitments(commitments_points.clone());
+
+    let (sL, sR) =
+      ScalarVector((0 .. (MN * 2)).map(|_| Scalar::random(&mut *rng)).collect::<Vec<_>>()).split();
+
+    let generators = GENERATORS();
+    let (mut alpha, A) = alpha_rho(&mut *rng, generators, &aL, &aR);
+    let (mut rho, S) = alpha_rho(&mut *rng, generators, &sL, &sR);
+
+    let y = hash_cache(&mut cache, &[A.compress().to_bytes(), S.compress().to_bytes()]);
+    let mut cache = keccak256_to_scalar(y.to_bytes());
+    let z = cache;
+
+    let l0 = aL - z;
+    let l1 = sL;
+
+    let mut zero_twos = Vec::with_capacity(MN);
+    let zpow = ScalarVector::powers(z, M + 2);
+    for j in 0 .. M {
+      for i in 0 .. N {
+        zero_twos.push(zpow[j + 2] * TWO_N()[i]);
+      }
+    }
+
+    let yMN = ScalarVector::powers(y, MN);
+    let r0 = ((aR + z) * &yMN) + &ScalarVector(zero_twos);
+    let r1 = yMN * &sR;
+
+    let (T1, T2, x, mut tau_x) = {
+      let t1 = l0.clone().inner_product(&r1) + r0.clone().inner_product(&l1);
+      let t2 = l1.clone().inner_product(&r1);
+
+      let mut tau1 = Scalar::random(&mut *rng);
+      let mut tau2 = Scalar::random(&mut *rng);
+
+      let T1 = multiexp(&[(t1, H()), (tau1, ED25519_BASEPOINT_POINT)]) * INV_EIGHT();
+      let T2 = multiexp(&[(t2, H()), (tau2, ED25519_BASEPOINT_POINT)]) * INV_EIGHT();
+
+      let x =
+        hash_cache(&mut cache, &[z.to_bytes(), T1.compress().to_bytes(), T2.compress().to_bytes()]);
+
+      let tau_x = (tau2 * (x * x)) + (tau1 * x);
+
+      tau1.zeroize();
+      tau2.zeroize();
+      (T1, T2, x, tau_x)
+    };
+
+    let mu = (x * rho) + alpha;
+    alpha.zeroize();
+    rho.zeroize();
+
+    for (i, gamma) in commitments.iter().map(|c| c.mask).enumerate() {
+      tau_x += zpow[i + 2] * gamma;
+    }
+
+    let l = l0 + &(l1 * x);
+    let r = r0 + &(r1 * x);
+
+    let t = l.clone().inner_product(&r);
+
+    let x_ip =
+      hash_cache(&mut cache, &[x.to_bytes(), tau_x.to_bytes(), mu.to_bytes(), t.to_bytes()]);
+
+    let mut a = l;
+    let mut b = r;
+
+    let yinv = y.invert();
+    let yinvpow = ScalarVector::powers(yinv, MN);
+
+    let mut G_proof = generators.G[.. a.len()].to_vec();
+    let mut H_proof = generators.H[.. a.len()].to_vec();
+    H_proof.iter_mut().zip(yinvpow.0.iter()).for_each(|(this_H, yinvpow)| *this_H *= yinvpow);
+    let U = H() * x_ip;
+
+    let mut L = Vec::with_capacity(logMN);
+    let mut R = Vec::with_capacity(logMN);
+
+    while a.len() != 1 {
+      let (aL, aR) = a.split();
+      let (bL, bR) = b.split();
+
+      let cL = aL.clone().inner_product(&bR);
+      let cR = aR.clone().inner_product(&bL);
+
+      let (G_L, G_R) = G_proof.split_at(aL.len());
+      let (H_L, H_R) = H_proof.split_at(aL.len());
+
+      let L_i = multiexp(&LR_statements(&aL, G_R, &bR, H_L, cL, U)) * INV_EIGHT();
+      let R_i = multiexp(&LR_statements(&aR, G_L, &bL, H_R, cR, U)) * INV_EIGHT();
+      L.push(L_i);
+      R.push(R_i);
+
+      let w = hash_cache(&mut cache, &[L_i.compress().to_bytes(), R_i.compress().to_bytes()]);
+      let winv = w.invert();
+
+      a = (aL * w) + &(aR * winv);
+      b = (bL * winv) + &(bR * w);
+
+      if a.len() != 1 {
+        G_proof = hadamard_fold(G_L, G_R, winv, w);
+        H_proof = hadamard_fold(H_L, H_R, w, winv);
+      }
+    }
+
+    let res = OriginalStruct { A, S, T1, T2, tau_x, mu, L, R, a: a[0], b: b[0], t };
+    debug_assert!(res.verify(rng, &commitments_points));
+    res
+  }
+
+  #[must_use]
+  fn verify_core<R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    verifier: &mut BulletproofsBatchVerifier,
+    commitments: &[EdwardsPoint],
+  ) -> bool {
+    // Verify commitments are valid
+    if commitments.is_empty() || (commitments.len() > MAX_M) {
+      return false;
+    }
+
+    // Verify L and R are properly sized
+    if self.L.len() != self.R.len() {
+      return false;
+    }
+
+    let (logMN, M, MN) = MN(commitments.len());
+    if self.L.len() != logMN {
+      return false;
+    }
+
+    // Rebuild all challenges
+    let (mut cache, commitments) = hash_commitments(commitments.iter().copied());
+    let y = hash_cache(&mut cache, &[self.A.compress().to_bytes(), self.S.compress().to_bytes()]);
+
+    let z = keccak256_to_scalar(y.to_bytes());
+    cache = z;
+
+    let x = hash_cache(
+      &mut cache,
+      &[z.to_bytes(), self.T1.compress().to_bytes(), self.T2.compress().to_bytes()],
+    );
+
+    let x_ip = hash_cache(
+      &mut cache,
+      &[x.to_bytes(), self.tau_x.to_bytes(), self.mu.to_bytes(), self.t.to_bytes()],
+    );
+
+    let mut w = Vec::with_capacity(logMN);
+    let mut winv = Vec::with_capacity(logMN);
+    for (L, R) in self.L.iter().zip(&self.R) {
+      w.push(hash_cache(&mut cache, &[L.compress().to_bytes(), R.compress().to_bytes()]));
+      winv.push(cache.invert());
+    }
+
+    // Convert the proof from * INV_EIGHT to its actual form
+    let normalize = |point: &EdwardsPoint| point.mul_by_cofactor();
+
+    let L = self.L.iter().map(normalize).collect::<Vec<_>>();
+    let R = self.R.iter().map(normalize).collect::<Vec<_>>();
+    let T1 = normalize(&self.T1);
+    let T2 = normalize(&self.T2);
+    let A = normalize(&self.A);
+    let S = normalize(&self.S);
+
+    let commitments = commitments.iter().map(EdwardsPoint::mul_by_cofactor).collect::<Vec<_>>();
+
+    // Verify it
+    let zpow = ScalarVector::powers(z, M + 3);
+
+    // First multiexp
+    {
+      let verifier_weight = Scalar::random(rng);
+
+      let ip1y = ScalarVector::powers(y, M * N).sum();
+      let mut k = -(zpow[2] * ip1y);
+      for j in 1 ..= M {
+        k -= zpow[j + 2] * IP12();
+      }
+      let y1 = self.t - ((z * ip1y) + k);
+      verifier.0.h -= verifier_weight * y1;
+
+      verifier.0.g -= verifier_weight * self.tau_x;
+
+      for (j, commitment) in commitments.iter().enumerate() {
+        verifier.0.other.push((verifier_weight * zpow[j + 2], *commitment));
+      }
+
+      verifier.0.other.push((verifier_weight * x, T1));
+      verifier.0.other.push((verifier_weight * (x * x), T2));
+    }
+
+    // Second multiexp
+    {
+      let verifier_weight = Scalar::random(rng);
+      let z3 = (self.t - (self.a * self.b)) * x_ip;
+      verifier.0.h += verifier_weight * z3;
+      verifier.0.g -= verifier_weight * self.mu;
+
+      verifier.0.other.push((verifier_weight, A));
+      verifier.0.other.push((verifier_weight * x, S));
+
+      {
+        let ypow = ScalarVector::powers(y, MN);
+        let yinv = y.invert();
+        let yinvpow = ScalarVector::powers(yinv, MN);
+
+        let w_cache = challenge_products(&w, &winv);
+
+        while verifier.0.g_bold.len() < MN {
+          verifier.0.g_bold.push(Scalar::ZERO);
+        }
+        while verifier.0.h_bold.len() < MN {
+          verifier.0.h_bold.push(Scalar::ZERO);
+        }
+
+        for i in 0 .. MN {
+          let g = (self.a * w_cache[i]) + z;
+          verifier.0.g_bold[i] -= verifier_weight * g;
+
+          let mut h = self.b * yinvpow[i] * w_cache[(!i) & (MN - 1)];
+          h -= ((zpow[(i / N) + 2] * TWO_N()[i % N]) + (z * ypow[i])) * yinvpow[i];
+          verifier.0.h_bold[i] -= verifier_weight * h;
+        }
+      }
+
+      for i in 0 .. logMN {
+        verifier.0.other.push((verifier_weight * (w[i] * w[i]), L[i]));
+        verifier.0.other.push((verifier_weight * (winv[i] * winv[i]), R[i]));
+      }
+    }
+
+    true
+  }
+
+  #[must_use]
+  pub(crate) fn verify<R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    commitments: &[EdwardsPoint],
+  ) -> bool {
+    let mut verifier = BulletproofsBatchVerifier(InternalBatchVerifier::new());
+    if self.verify_core(rng, &mut verifier, commitments) {
+      verifier.verify()
+    } else {
+      false
+    }
+  }
+
+  #[must_use]
+  pub(crate) fn batch_verify<R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    verifier: &mut BulletproofsBatchVerifier,
+    commitments: &[EdwardsPoint],
+  ) -> bool {
+    self.verify_core(rng, verifier, commitments)
+  }
+}

coins/monero/ringct/bulletproofs/src/plus/aggregate_range_proof.rs

@@ -0,0 +1,260 @@
+use std_shims::vec::Vec;
+
+use rand_core::{RngCore, CryptoRng};
+use zeroize::{Zeroize, ZeroizeOnDrop, Zeroizing};
+
+use curve25519_dalek::{traits::Identity, scalar::Scalar, edwards::EdwardsPoint};
+
+use monero_primitives::{INV_EIGHT, Commitment, keccak256_to_scalar};
+
+use crate::{
+  batch_verifier::BulletproofsPlusBatchVerifier,
+  core::{MAX_M, N, multiexp, multiexp_vartime},
+  plus::{
+    ScalarVector, PointVector, GeneratorsList, BpPlusGenerators,
+    transcript::*,
+    weighted_inner_product::{WipStatement, WipWitness, WipProof},
+    padded_pow_of_2, u64_decompose,
+  },
+};
+
+// Figure 3 of the Bulletproofs+ Paper
+#[derive(Clone, Debug)]
+pub(crate) struct AggregateRangeStatement {
+  generators: BpPlusGenerators,
+  V: Vec<EdwardsPoint>,
+}
+
+impl Zeroize for AggregateRangeStatement {
+  fn zeroize(&mut self) {
+    self.V.zeroize();
+  }
+}
+
+#[derive(Clone, Debug, Zeroize, ZeroizeOnDrop)]
+pub(crate) struct AggregateRangeWitness(Vec<Commitment>);
+
+impl AggregateRangeWitness {
+  pub(crate) fn new(commitments: Vec<Commitment>) -> Option<Self> {
+    if commitments.is_empty() || (commitments.len() > MAX_M) {
+      return None;
+    }
+
+    Some(AggregateRangeWitness(commitments))
+  }
+}
+
+/// Internal structure representing a Bulletproof+, as used in Monero.
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize)]
+pub struct AggregateRangeProof {
+  pub(crate) A: EdwardsPoint,
+  pub(crate) wip: WipProof,
+}
+
+struct AHatComputation {
+  y: Scalar,
+  d_descending_y_plus_z: ScalarVector,
+  y_mn_plus_one: Scalar,
+  z: Scalar,
+  z_pow: ScalarVector,
+  A_hat: EdwardsPoint,
+}
+
+impl AggregateRangeStatement {
+  pub(crate) fn new(V: Vec<EdwardsPoint>) -> Option<Self> {
+    if V.is_empty() || (V.len() > MAX_M) {
+      return None;
+    }
+
+    Some(Self { generators: BpPlusGenerators::new(), V })
+  }
+
+  fn transcript_A(transcript: &mut Scalar, A: EdwardsPoint) -> (Scalar, Scalar) {
+    let y = keccak256_to_scalar(
+      [transcript.to_bytes().as_ref(), A.compress().to_bytes().as_ref()].concat(),
+    );
+    let z = keccak256_to_scalar(y.to_bytes().as_ref());
+    *transcript = z;
+    (y, z)
+  }
+
+  fn d_j(j: usize, m: usize) -> ScalarVector {
+    let mut d_j = Vec::with_capacity(m * N);
+    for _ in 0 .. (j - 1) * N {
+      d_j.push(Scalar::ZERO);
+    }
+    d_j.append(&mut ScalarVector::powers(Scalar::from(2u8), N).0);
+    for _ in 0 .. (m - j) * N {
+      d_j.push(Scalar::ZERO);
+    }
+    ScalarVector(d_j)
+  }
+
+  fn compute_A_hat(
+    mut V: PointVector,
+    generators: &BpPlusGenerators,
+    transcript: &mut Scalar,
+    mut A: EdwardsPoint,
+  ) -> AHatComputation {
+    let (y, z) = Self::transcript_A(transcript, A);
+    A = A.mul_by_cofactor();
+
+    while V.len() < padded_pow_of_2(V.len()) {
+      V.0.push(EdwardsPoint::identity());
+    }
+    let mn = V.len() * N;
+
+    // 2, 4, 6, 8... powers of z, of length equivalent to the amount of commitments
+    let mut z_pow = Vec::with_capacity(V.len());
+    // z**2
+    z_pow.push(z * z);
+
+    let mut d = ScalarVector::new(mn);
+    for j in 1 ..= V.len() {
+      z_pow.push(*z_pow.last().unwrap() * z_pow[0]);
+      d = d + &(Self::d_j(j, V.len()) * (z_pow[j - 1]));
+    }
+
+    let mut ascending_y = ScalarVector(vec![y]);
+    for i in 1 .. d.len() {
+      ascending_y.0.push(ascending_y[i - 1] * y);
+    }
+    let y_pows = ascending_y.clone().sum();
+
+    let mut descending_y = ascending_y.clone();
+    descending_y.0.reverse();
+
+    let d_descending_y = d.clone() * &descending_y;
+    let d_descending_y_plus_z = d_descending_y + z;
+
+    let y_mn_plus_one = descending_y[0] * y;
+
+    let mut commitment_accum = EdwardsPoint::identity();
+    for (j, commitment) in V.0.iter().enumerate() {
+      commitment_accum += *commitment * z_pow[j];
+    }
+
+    let neg_z = -z;
+    let mut A_terms = Vec::with_capacity((generators.len() * 2) + 2);
+    for (i, d_y_z) in d_descending_y_plus_z.0.iter().enumerate() {
+      A_terms.push((neg_z, generators.generator(GeneratorsList::GBold, i)));
+      A_terms.push((*d_y_z, generators.generator(GeneratorsList::HBold, i)));
+    }
+    A_terms.push((y_mn_plus_one, commitment_accum));
+    A_terms.push((
+      ((y_pows * z) - (d.sum() * y_mn_plus_one * z) - (y_pows * (z * z))),
+      BpPlusGenerators::g(),
+    ));
+
+    AHatComputation {
+      y,
+      d_descending_y_plus_z,
+      y_mn_plus_one,
+      z,
+      z_pow: ScalarVector(z_pow),
+      A_hat: A + multiexp_vartime(&A_terms),
+    }
+  }
+
+  pub(crate) fn prove<R: RngCore + CryptoRng>(
+    self,
+    rng: &mut R,
+    witness: &AggregateRangeWitness,
+  ) -> Option<AggregateRangeProof> {
+    // Check for consistency with the witness
+    if self.V.len() != witness.0.len() {
+      return None;
+    }
+    for (commitment, witness) in self.V.iter().zip(witness.0.iter()) {
+      if witness.calculate() != *commitment {
+        return None;
+      }
+    }
+
+    let Self { generators, V } = self;
+    // Monero expects all of these points to be torsion-free
+    // Generally, for Bulletproofs, it sends points * INV_EIGHT and then performs a torsion clear
+    // by multiplying by 8
+    // This also restores the original value due to the preprocessing
+    // Commitments aren't transmitted INV_EIGHT though, so this multiplies by INV_EIGHT to enable
+    // clearing its cofactor without mutating the value
+    // For some reason, these values are transcripted * INV_EIGHT, not as transmitted
+    let V = V.into_iter().map(|V| V * INV_EIGHT()).collect::<Vec<_>>();
+    let mut transcript = initial_transcript(V.iter());
+    let mut V = V.iter().map(EdwardsPoint::mul_by_cofactor).collect::<Vec<_>>();
+
+    // Pad V
+    while V.len() < padded_pow_of_2(V.len()) {
+      V.push(EdwardsPoint::identity());
+    }
+
+    let generators = generators.reduce(V.len() * N);
+
+    let mut d_js = Vec::with_capacity(V.len());
+    let mut a_l = ScalarVector(Vec::with_capacity(V.len() * N));
+    for j in 1 ..= V.len() {
+      d_js.push(Self::d_j(j, V.len()));
+      #[allow(clippy::map_unwrap_or)]
+      a_l.0.append(
+        &mut u64_decompose(
+          *witness.0.get(j - 1).map(|commitment| &commitment.amount).unwrap_or(&0),
+        )
+        .0,
+      );
+    }
+
+    let a_r = a_l.clone() - Scalar::ONE;
+
+    let alpha = Scalar::random(&mut *rng);
+
+    let mut A_terms = Vec::with_capacity((generators.len() * 2) + 1);
+    for (i, a_l) in a_l.0.iter().enumerate() {
+      A_terms.push((*a_l, generators.generator(GeneratorsList::GBold, i)));
+    }
+    for (i, a_r) in a_r.0.iter().enumerate() {
+      A_terms.push((*a_r, generators.generator(GeneratorsList::HBold, i)));
+    }
+    A_terms.push((alpha, BpPlusGenerators::h()));
+    let mut A = multiexp(&A_terms);
+    A_terms.zeroize();
+
+    // Multiply by INV_EIGHT per earlier commentary
+    A *= INV_EIGHT();
+
+    let AHatComputation { y, d_descending_y_plus_z, y_mn_plus_one, z, z_pow, A_hat } =
+      Self::compute_A_hat(PointVector(V), &generators, &mut transcript, A);
+
+    let a_l = a_l - z;
+    let a_r = a_r + &d_descending_y_plus_z;
+    let mut alpha = alpha;
+    for j in 1 ..= witness.0.len() {
+      alpha += z_pow[j - 1] * witness.0[j - 1].mask * y_mn_plus_one;
+    }
+
+    Some(AggregateRangeProof {
+      A,
+      wip: WipStatement::new(generators, A_hat, y)
+        .prove(rng, transcript, &Zeroizing::new(WipWitness::new(a_l, a_r, alpha).unwrap()))
+        .unwrap(),
+    })
+  }
+
+  pub(crate) fn verify<R: RngCore + CryptoRng>(
+    self,
+    rng: &mut R,
+    verifier: &mut BulletproofsPlusBatchVerifier,
+    proof: AggregateRangeProof,
+  ) -> bool {
+    let Self { generators, V } = self;
+
+    let V = V.into_iter().map(|V| V * INV_EIGHT()).collect::<Vec<_>>();
+    let mut transcript = initial_transcript(V.iter());
+    let V = V.iter().map(EdwardsPoint::mul_by_cofactor).collect::<Vec<_>>();
+
+    let generators = generators.reduce(V.len() * N);
+
+    let AHatComputation { y, A_hat, .. } =
+      Self::compute_A_hat(PointVector(V), &generators, &mut transcript, proof.A);
+    WipStatement::new(generators, A_hat, y).verify(rng, verifier, transcript, proof.wip)
+  }
+}

coins/monero/ringct/bulletproofs/src/plus/mod.rs

@@ -0,0 +1,85 @@
+#![allow(non_snake_case)]
+
+use std_shims::sync::OnceLock;
+
+use curve25519_dalek::{constants::ED25519_BASEPOINT_POINT, scalar::Scalar, edwards::EdwardsPoint};
+
+use monero_generators::{H, Generators};
+
+pub(crate) use crate::scalar_vector::ScalarVector;
+
+mod point_vector;
+pub(crate) use point_vector::PointVector;
+
+pub(crate) mod transcript;
+pub(crate) mod weighted_inner_product;
+pub(crate) use weighted_inner_product::*;
+pub(crate) mod aggregate_range_proof;
+pub(crate) use aggregate_range_proof::*;
+
+pub(crate) fn padded_pow_of_2(i: usize) -> usize {
+  let mut next_pow_of_2 = 1;
+  while next_pow_of_2 < i {
+    next_pow_of_2 <<= 1;
+  }
+  next_pow_of_2
+}
+
+#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum GeneratorsList {
+  GBold,
+  HBold,
+}
+
+// TODO: Table these
+#[derive(Clone, Debug)]
+pub(crate) struct BpPlusGenerators {
+  g_bold: &'static [EdwardsPoint],
+  h_bold: &'static [EdwardsPoint],
+}
+
+include!(concat!(env!("OUT_DIR"), "/generators_plus.rs"));
+
+impl BpPlusGenerators {
+  #[allow(clippy::new_without_default)]
+  pub(crate) fn new() -> Self {
+    let gens = GENERATORS();
+    BpPlusGenerators { g_bold: &gens.G, h_bold: &gens.H }
+  }
+
+  pub(crate) fn len(&self) -> usize {
+    self.g_bold.len()
+  }
+
+  pub(crate) fn g() -> EdwardsPoint {
+    H()
+  }
+
+  pub(crate) fn h() -> EdwardsPoint {
+    ED25519_BASEPOINT_POINT
+  }
+
+  pub(crate) fn generator(&self, list: GeneratorsList, i: usize) -> EdwardsPoint {
+    match list {
+      GeneratorsList::GBold => self.g_bold[i],
+      GeneratorsList::HBold => self.h_bold[i],
+    }
+  }
+
+  pub(crate) fn reduce(&self, generators: usize) -> Self {
+    // Round to the nearest power of 2
+    let generators = padded_pow_of_2(generators);
+    assert!(generators <= self.g_bold.len());
+
+    BpPlusGenerators { g_bold: &self.g_bold[.. generators], h_bold: &self.h_bold[.. generators] }
+  }
+}
+
+// Returns the little-endian decomposition.
+fn u64_decompose(value: u64) -> ScalarVector {
+  let mut bits = ScalarVector::new(64);
+  for bit in 0 .. 64 {
+    bits[bit] = Scalar::from((value >> bit) & 1);
+  }
+  bits
+}

coins/monero/ringct/bulletproofs/src/plus/point_vector.rs

@@ -0,0 +1,48 @@
+use core::ops::{Index, IndexMut};
+use std_shims::vec::Vec;
+
+use zeroize::{Zeroize, ZeroizeOnDrop};
+
+use curve25519_dalek::edwards::EdwardsPoint;
+
+#[cfg(test)]
+use crate::{core::multiexp, plus::ScalarVector};
+
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
+pub(crate) struct PointVector(pub(crate) Vec<EdwardsPoint>);
+
+impl Index<usize> for PointVector {
+  type Output = EdwardsPoint;
+  fn index(&self, index: usize) -> &EdwardsPoint {
+    &self.0[index]
+  }
+}
+
+impl IndexMut<usize> for PointVector {
+  fn index_mut(&mut self, index: usize) -> &mut EdwardsPoint {
+    &mut self.0[index]
+  }
+}
+
+impl PointVector {
+  #[cfg(test)]
+  pub(crate) fn multiexp(&self, vector: &ScalarVector) -> EdwardsPoint {
+    debug_assert_eq!(self.len(), vector.len());
+    let mut res = Vec::with_capacity(self.len());
+    for (point, scalar) in self.0.iter().copied().zip(vector.0.iter().copied()) {
+      res.push((scalar, point));
+    }
+    multiexp(&res)
+  }
+
+  pub(crate) fn len(&self) -> usize {
+    self.0.len()
+  }
+
+  pub(crate) fn split(mut self) -> (Self, Self) {
+    debug_assert!(self.len() > 1);
+    let r = self.0.split_off(self.0.len() / 2);
+    debug_assert_eq!(self.len(), r.len());
+    (self, PointVector(r))
+  }
+}

coins/monero/ringct/bulletproofs/src/plus/transcript.rs

@@ -0,0 +1,20 @@
+use std_shims::{sync::OnceLock, vec::Vec};
+
+use curve25519_dalek::{scalar::Scalar, edwards::EdwardsPoint};
+
+use monero_generators::hash_to_point;
+use monero_primitives::{keccak256, keccak256_to_scalar};
+
+// Monero starts BP+ transcripts with the following constant.
+static TRANSCRIPT_CELL: OnceLock<[u8; 32]> = OnceLock::new();
+pub(crate) fn TRANSCRIPT() -> [u8; 32] {
+  // Why this uses a hash_to_point is completely unknown.
+  *TRANSCRIPT_CELL
+    .get_or_init(|| hash_to_point(keccak256(b"bulletproof_plus_transcript")).compress().to_bytes())
+}
+
+pub(crate) fn initial_transcript(commitments: core::slice::Iter<'_, EdwardsPoint>) -> Scalar {
+  let commitments_hash =
+    keccak256_to_scalar(commitments.flat_map(|V| V.compress().to_bytes()).collect::<Vec<_>>());
+  keccak256_to_scalar([TRANSCRIPT().as_ref(), &commitments_hash.to_bytes()].concat())
+}

coins/monero/ringct/bulletproofs/src/plus/weighted_inner_product.rs

@@ -0,0 +1,443 @@
+use std_shims::vec::Vec;
+
+use rand_core::{RngCore, CryptoRng};
+use zeroize::{Zeroize, ZeroizeOnDrop};
+
+use curve25519_dalek::{scalar::Scalar, edwards::EdwardsPoint};
+
+use monero_primitives::{INV_EIGHT, keccak256_to_scalar};
+use crate::{
+  core::{multiexp, multiexp_vartime},
+  batch_verifier::BulletproofsPlusBatchVerifier,
+  plus::{ScalarVector, PointVector, GeneratorsList, BpPlusGenerators, padded_pow_of_2},
+};
+
+// Figure 1 of the Bulletproofs+ paper
+#[derive(Clone, Debug)]
+pub(crate) struct WipStatement {
+  generators: BpPlusGenerators,
+  P: EdwardsPoint,
+  y: ScalarVector,
+}
+
+impl Zeroize for WipStatement {
+  fn zeroize(&mut self) {
+    self.P.zeroize();
+    self.y.zeroize();
+  }
+}
+
+#[derive(Clone, Debug, Zeroize, ZeroizeOnDrop)]
+pub(crate) struct WipWitness {
+  a: ScalarVector,
+  b: ScalarVector,
+  alpha: Scalar,
+}
+
+impl WipWitness {
+  pub(crate) fn new(mut a: ScalarVector, mut b: ScalarVector, alpha: Scalar) -> Option<Self> {
+    if a.0.is_empty() || (a.len() != b.len()) {
+      return None;
+    }
+
+    // Pad to the nearest power of 2
+    let missing = padded_pow_of_2(a.len()) - a.len();
+    a.0.reserve(missing);
+    b.0.reserve(missing);
+    for _ in 0 .. missing {
+      a.0.push(Scalar::ZERO);
+      b.0.push(Scalar::ZERO);
+    }
+
+    Some(Self { a, b, alpha })
+  }
+}
+
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize)]
+pub(crate) struct WipProof {
+  pub(crate) L: Vec<EdwardsPoint>,
+  pub(crate) R: Vec<EdwardsPoint>,
+  pub(crate) A: EdwardsPoint,
+  pub(crate) B: EdwardsPoint,
+  pub(crate) r_answer: Scalar,
+  pub(crate) s_answer: Scalar,
+  pub(crate) delta_answer: Scalar,
+}
+
+impl WipStatement {
+  pub(crate) fn new(generators: BpPlusGenerators, P: EdwardsPoint, y: Scalar) -> Self {
+    debug_assert_eq!(generators.len(), padded_pow_of_2(generators.len()));
+
+    // y ** n
+    let mut y_vec = ScalarVector::new(generators.len());
+    y_vec[0] = y;
+    for i in 1 .. y_vec.len() {
+      y_vec[i] = y_vec[i - 1] * y;
+    }
+
+    Self { generators, P, y: y_vec }
+  }
+
+  fn transcript_L_R(transcript: &mut Scalar, L: EdwardsPoint, R: EdwardsPoint) -> Scalar {
+    let e = keccak256_to_scalar(
+      [
+        transcript.to_bytes().as_ref(),
+        L.compress().to_bytes().as_ref(),
+        R.compress().to_bytes().as_ref(),
+      ]
+      .concat(),
+    );
+    *transcript = e;
+    e
+  }
+
+  fn transcript_A_B(transcript: &mut Scalar, A: EdwardsPoint, B: EdwardsPoint) -> Scalar {
+    let e = keccak256_to_scalar(
+      [
+        transcript.to_bytes().as_ref(),
+        A.compress().to_bytes().as_ref(),
+        B.compress().to_bytes().as_ref(),
+      ]
+      .concat(),
+    );
+    *transcript = e;
+    e
+  }
+
+  // Prover's variant of the shared code block to calculate G/H/P when n > 1
+  // Returns each permutation of G/H since the prover needs to do operation on each permutation
+  // P is dropped as it's unused in the prover's path
+  // TODO: It'd still probably be faster to keep in terms of the original generators, both between
+  // the reduced amount of group operations and the potential tabling of the generators under
+  // multiexp
+  #[allow(clippy::too_many_arguments)]
+  fn next_G_H(
+    transcript: &mut Scalar,
+    mut g_bold1: PointVector,
+    mut g_bold2: PointVector,
+    mut h_bold1: PointVector,
+    mut h_bold2: PointVector,
+    L: EdwardsPoint,
+    R: EdwardsPoint,
+    y_inv_n_hat: Scalar,
+  ) -> (Scalar, Scalar, Scalar, Scalar, PointVector, PointVector) {
+    debug_assert_eq!(g_bold1.len(), g_bold2.len());
+    debug_assert_eq!(h_bold1.len(), h_bold2.len());
+    debug_assert_eq!(g_bold1.len(), h_bold1.len());
+
+    let e = Self::transcript_L_R(transcript, L, R);
+    let inv_e = e.invert();
+
+    // This vartime is safe as all of these arguments are public
+    let mut new_g_bold = Vec::with_capacity(g_bold1.len());
+    let e_y_inv = e * y_inv_n_hat;
+    for g_bold in g_bold1.0.drain(..).zip(g_bold2.0.drain(..)) {
+      new_g_bold.push(multiexp_vartime(&[(inv_e, g_bold.0), (e_y_inv, g_bold.1)]));
+    }
+
+    let mut new_h_bold = Vec::with_capacity(h_bold1.len());
+    for h_bold in h_bold1.0.drain(..).zip(h_bold2.0.drain(..)) {
+      new_h_bold.push(multiexp_vartime(&[(e, h_bold.0), (inv_e, h_bold.1)]));
+    }
+
+    let e_square = e * e;
+    let inv_e_square = inv_e * inv_e;
+
+    (e, inv_e, e_square, inv_e_square, PointVector(new_g_bold), PointVector(new_h_bold))
+  }
+
+  /*
+  This has room for optimization worth investigating further. It currently takes
+  an iterative approach. It can be optimized further via divide and conquer.
+
+  Assume there are 4 challenges.
+
+  Iterative approach (current):
+    1. Do the optimal multiplications across challenge column 0 and 1.
+    2. Do the optimal multiplications across that result and column 2.
+    3. Do the optimal multiplications across that result and column 3.
+
+  Divide and conquer (worth investigating further):
+    1. Do the optimal multiplications across challenge column 0 and 1.
+    2. Do the optimal multiplications across challenge column 2 and 3.
+    3. Multiply both results together.
+
+  When there are 4 challenges (n=16), the iterative approach does 28 multiplications
+  versus divide and conquer's 24.
+  */
+  fn challenge_products(challenges: &[(Scalar, Scalar)]) -> Vec<Scalar> {
+    let mut products = vec![Scalar::ONE; 1 << challenges.len()];
+
+    if !challenges.is_empty() {
+      products[0] = challenges[0].1;
+      products[1] = challenges[0].0;
+
+      for (j, challenge) in challenges.iter().enumerate().skip(1) {
+        let mut slots = (1 << (j + 1)) - 1;
+        while slots > 0 {
+          products[slots] = products[slots / 2] * challenge.0;
+          products[slots - 1] = products[slots / 2] * challenge.1;
+
+          slots = slots.saturating_sub(2);
+        }
+      }
+
+      // Sanity check since if the above failed to populate, it'd be critical
+      for product in &products {
+        debug_assert!(*product != Scalar::ZERO);
+      }
+    }
+
+    products
+  }
+
+  pub(crate) fn prove<R: RngCore + CryptoRng>(
+    self,
+    rng: &mut R,
+    mut transcript: Scalar,
+    witness: &WipWitness,
+  ) -> Option<WipProof> {
+    let WipStatement { generators, P, mut y } = self;
+    #[cfg(not(debug_assertions))]
+    let _ = P;
+
+    if generators.len() != witness.a.len() {
+      return None;
+    }
+    let (g, h) = (BpPlusGenerators::g(), BpPlusGenerators::h());
+    let mut g_bold = vec![];
+    let mut h_bold = vec![];
+    for i in 0 .. generators.len() {
+      g_bold.push(generators.generator(GeneratorsList::GBold, i));
+      h_bold.push(generators.generator(GeneratorsList::HBold, i));
+    }
+    let mut g_bold = PointVector(g_bold);
+    let mut h_bold = PointVector(h_bold);
+
+    // Check P has the expected relationship
+    #[cfg(debug_assertions)]
+    {
+      let mut P_terms = witness
+        .a
+        .0
+        .iter()
+        .copied()
+        .zip(g_bold.0.iter().copied())
+        .chain(witness.b.0.iter().copied().zip(h_bold.0.iter().copied()))
+        .collect::<Vec<_>>();
+      P_terms.push((witness.a.clone().weighted_inner_product(&witness.b, &y), g));
+      P_terms.push((witness.alpha, h));
+      debug_assert_eq!(multiexp(&P_terms), P);
+      P_terms.zeroize();
+    }
+
+    let mut a = witness.a.clone();
+    let mut b = witness.b.clone();
+    let mut alpha = witness.alpha;
+
+    // From here on, g_bold.len() is used as n
+    debug_assert_eq!(g_bold.len(), a.len());
+
+    let mut L_vec = vec![];
+    let mut R_vec = vec![];
+
+    // else n > 1 case from figure 1
+    while g_bold.len() > 1 {
+      let (a1, a2) = a.clone().split();
+      let (b1, b2) = b.clone().split();
+      let (g_bold1, g_bold2) = g_bold.split();
+      let (h_bold1, h_bold2) = h_bold.split();
+
+      let n_hat = g_bold1.len();
+      debug_assert_eq!(a1.len(), n_hat);
+      debug_assert_eq!(a2.len(), n_hat);
+      debug_assert_eq!(b1.len(), n_hat);
+      debug_assert_eq!(b2.len(), n_hat);
+      debug_assert_eq!(g_bold1.len(), n_hat);
+      debug_assert_eq!(g_bold2.len(), n_hat);
+      debug_assert_eq!(h_bold1.len(), n_hat);
+      debug_assert_eq!(h_bold2.len(), n_hat);
+
+      let y_n_hat = y[n_hat - 1];
+      y.0.truncate(n_hat);
+
+      let d_l = Scalar::random(&mut *rng);
+      let d_r = Scalar::random(&mut *rng);
+
+      let c_l = a1.clone().weighted_inner_product(&b2, &y);
+      let c_r = (a2.clone() * y_n_hat).weighted_inner_product(&b1, &y);
+
+      // TODO: Calculate these with a batch inversion
+      let y_inv_n_hat = y_n_hat.invert();
+
+      let mut L_terms = (a1.clone() * y_inv_n_hat)
+        .0
+        .drain(..)
+        .zip(g_bold2.0.iter().copied())
+        .chain(b2.0.iter().copied().zip(h_bold1.0.iter().copied()))
+        .collect::<Vec<_>>();
+      L_terms.push((c_l, g));
+      L_terms.push((d_l, h));
+      let L = multiexp(&L_terms) * INV_EIGHT();
+      L_vec.push(L);
+      L_terms.zeroize();
+
+      let mut R_terms = (a2.clone() * y_n_hat)
+        .0
+        .drain(..)
+        .zip(g_bold1.0.iter().copied())
+        .chain(b1.0.iter().copied().zip(h_bold2.0.iter().copied()))
+        .collect::<Vec<_>>();
+      R_terms.push((c_r, g));
+      R_terms.push((d_r, h));
+      let R = multiexp(&R_terms) * INV_EIGHT();
+      R_vec.push(R);
+      R_terms.zeroize();
+
+      let (e, inv_e, e_square, inv_e_square);
+      (e, inv_e, e_square, inv_e_square, g_bold, h_bold) =
+        Self::next_G_H(&mut transcript, g_bold1, g_bold2, h_bold1, h_bold2, L, R, y_inv_n_hat);
+
+      a = (a1 * e) + &(a2 * (y_n_hat * inv_e));
+      b = (b1 * inv_e) + &(b2 * e);
+      alpha += (d_l * e_square) + (d_r * inv_e_square);
+
+      debug_assert_eq!(g_bold.len(), a.len());
+      debug_assert_eq!(g_bold.len(), h_bold.len());
+      debug_assert_eq!(g_bold.len(), b.len());
+    }
+
+    // n == 1 case from figure 1
+    debug_assert_eq!(g_bold.len(), 1);
+    debug_assert_eq!(h_bold.len(), 1);
+
+    debug_assert_eq!(a.len(), 1);
+    debug_assert_eq!(b.len(), 1);
+
+    let r = Scalar::random(&mut *rng);
+    let s = Scalar::random(&mut *rng);
+    let delta = Scalar::random(&mut *rng);
+    let eta = Scalar::random(&mut *rng);
+
+    let ry = r * y[0];
+
+    let mut A_terms =
+      vec![(r, g_bold[0]), (s, h_bold[0]), ((ry * b[0]) + (s * y[0] * a[0]), g), (delta, h)];
+    let A = multiexp(&A_terms) * INV_EIGHT();
+    A_terms.zeroize();
+
+    let mut B_terms = vec![(ry * s, g), (eta, h)];
+    let B = multiexp(&B_terms) * INV_EIGHT();
+    B_terms.zeroize();
+
+    let e = Self::transcript_A_B(&mut transcript, A, B);
+
+    let r_answer = r + (a[0] * e);
+    let s_answer = s + (b[0] * e);
+    let delta_answer = eta + (delta * e) + (alpha * (e * e));
+
+    Some(WipProof { L: L_vec, R: R_vec, A, B, r_answer, s_answer, delta_answer })
+  }
+
+  pub(crate) fn verify<R: RngCore + CryptoRng>(
+    self,
+    rng: &mut R,
+    verifier: &mut BulletproofsPlusBatchVerifier,
+    mut transcript: Scalar,
+    mut proof: WipProof,
+  ) -> bool {
+    let verifier_weight = Scalar::random(rng);
+
+    let WipStatement { generators, P, y } = self;
+
+    // Verify the L/R lengths
+    {
+      let mut lr_len = 0;
+      while (1 << lr_len) < generators.len() {
+        lr_len += 1;
+      }
+      if (proof.L.len() != lr_len) ||
+        (proof.R.len() != lr_len) ||
+        (generators.len() != (1 << lr_len))
+      {
+        return false;
+      }
+    }
+
+    let inv_y = {
+      let inv_y = y[0].invert();
+      let mut res = Vec::with_capacity(y.len());
+      res.push(inv_y);
+      while res.len() < y.len() {
+        res.push(inv_y * res.last().unwrap());
+      }
+      res
+    };
+
+    let mut e_is = Vec::with_capacity(proof.L.len());
+    for (L, R) in proof.L.iter_mut().zip(proof.R.iter_mut()) {
+      e_is.push(Self::transcript_L_R(&mut transcript, *L, *R));
+      *L = L.mul_by_cofactor();
+      *R = R.mul_by_cofactor();
+    }
+
+    let e = Self::transcript_A_B(&mut transcript, proof.A, proof.B);
+    proof.A = proof.A.mul_by_cofactor();
+    proof.B = proof.B.mul_by_cofactor();
+    let neg_e_square = verifier_weight * -(e * e);
+
+    verifier.0.other.push((neg_e_square, P));
+
+    let mut challenges = Vec::with_capacity(proof.L.len());
+    let product_cache = {
+      let mut inv_e_is = e_is.clone();
+      Scalar::batch_invert(&mut inv_e_is);
+
+      debug_assert_eq!(e_is.len(), inv_e_is.len());
+      debug_assert_eq!(e_is.len(), proof.L.len());
+      debug_assert_eq!(e_is.len(), proof.R.len());
+      for ((e_i, inv_e_i), (L, R)) in
+        e_is.drain(..).zip(inv_e_is.drain(..)).zip(proof.L.iter().zip(proof.R.iter()))
+      {
+        debug_assert_eq!(e_i.invert(), inv_e_i);
+
+        challenges.push((e_i, inv_e_i));
+
+        let e_i_square = e_i * e_i;
+        let inv_e_i_square = inv_e_i * inv_e_i;
+        verifier.0.other.push((neg_e_square * e_i_square, *L));
+        verifier.0.other.push((neg_e_square * inv_e_i_square, *R));
+      }
+
+      Self::challenge_products(&challenges)
+    };
+
+    while verifier.0.g_bold.len() < generators.len() {
+      verifier.0.g_bold.push(Scalar::ZERO);
+    }
+    while verifier.0.h_bold.len() < generators.len() {
+      verifier.0.h_bold.push(Scalar::ZERO);
+    }
+
+    let re = proof.r_answer * e;
+    for i in 0 .. generators.len() {
+      let mut scalar = product_cache[i] * re;
+      if i > 0 {
+        scalar *= inv_y[i - 1];
+      }
+      verifier.0.g_bold[i] += verifier_weight * scalar;
+    }
+
+    let se = proof.s_answer * e;
+    for i in 0 .. generators.len() {
+      verifier.0.h_bold[i] += verifier_weight * (se * product_cache[product_cache.len() - 1 - i]);
+    }
+
+    verifier.0.other.push((verifier_weight * -e, proof.A));
+    verifier.0.g += verifier_weight * (proof.r_answer * y[0] * proof.s_answer);
+    verifier.0.h += verifier_weight * proof.delta_answer;
+    verifier.0.other.push((-verifier_weight, proof.B));
+
+    true
+  }
+}

coins/monero/ringct/bulletproofs/src/scalar_vector.rs

@@ -0,0 +1,138 @@
+use core::{
+  borrow::Borrow,
+  ops::{Index, IndexMut, Add, Sub, Mul},
+};
+use std_shims::vec::Vec;
+
+use zeroize::{Zeroize, ZeroizeOnDrop};
+
+use curve25519_dalek::{scalar::Scalar, edwards::EdwardsPoint};
+
+use crate::core::multiexp;
+
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
+pub(crate) struct ScalarVector(pub(crate) Vec<Scalar>);
+
+impl Index<usize> for ScalarVector {
+  type Output = Scalar;
+  fn index(&self, index: usize) -> &Scalar {
+    &self.0[index]
+  }
+}
+impl IndexMut<usize> for ScalarVector {
+  fn index_mut(&mut self, index: usize) -> &mut Scalar {
+    &mut self.0[index]
+  }
+}
+
+impl<S: Borrow<Scalar>> Add<S> for ScalarVector {
+  type Output = ScalarVector;
+  fn add(mut self, scalar: S) -> ScalarVector {
+    for s in &mut self.0 {
+      *s += scalar.borrow();
+    }
+    self
+  }
+}
+impl<S: Borrow<Scalar>> Sub<S> for ScalarVector {
+  type Output = ScalarVector;
+  fn sub(mut self, scalar: S) -> ScalarVector {
+    for s in &mut self.0 {
+      *s -= scalar.borrow();
+    }
+    self
+  }
+}
+impl<S: Borrow<Scalar>> Mul<S> for ScalarVector {
+  type Output = ScalarVector;
+  fn mul(mut self, scalar: S) -> ScalarVector {
+    for s in &mut self.0 {
+      *s *= scalar.borrow();
+    }
+    self
+  }
+}
+
+impl Add<&ScalarVector> for ScalarVector {
+  type Output = ScalarVector;
+  fn add(mut self, other: &ScalarVector) -> ScalarVector {
+    debug_assert_eq!(self.len(), other.len());
+    for (s, o) in self.0.iter_mut().zip(other.0.iter()) {
+      *s += o;
+    }
+    self
+  }
+}
+impl Sub<&ScalarVector> for ScalarVector {
+  type Output = ScalarVector;
+  fn sub(mut self, other: &ScalarVector) -> ScalarVector {
+    debug_assert_eq!(self.len(), other.len());
+    for (s, o) in self.0.iter_mut().zip(other.0.iter()) {
+      *s -= o;
+    }
+    self
+  }
+}
+impl Mul<&ScalarVector> for ScalarVector {
+  type Output = ScalarVector;
+  fn mul(mut self, other: &ScalarVector) -> ScalarVector {
+    debug_assert_eq!(self.len(), other.len());
+    for (s, o) in self.0.iter_mut().zip(other.0.iter()) {
+      *s *= o;
+    }
+    self
+  }
+}
+
+impl Mul<&[EdwardsPoint]> for &ScalarVector {
+  type Output = EdwardsPoint;
+  fn mul(self, b: &[EdwardsPoint]) -> EdwardsPoint {
+    debug_assert_eq!(self.len(), b.len());
+    let mut multiexp_args = self.0.iter().copied().zip(b.iter().copied()).collect::<Vec<_>>();
+    let res = multiexp(&multiexp_args);
+    multiexp_args.zeroize();
+    res
+  }
+}
+
+impl ScalarVector {
+  pub(crate) fn new(len: usize) -> Self {
+    ScalarVector(vec![Scalar::ZERO; len])
+  }
+
+  pub(crate) fn powers(x: Scalar, len: usize) -> Self {
+    debug_assert!(len != 0);
+
+    let mut res = Vec::with_capacity(len);
+    res.push(Scalar::ONE);
+    res.push(x);
+    for i in 2 .. len {
+      res.push(res[i - 1] * x);
+    }
+    res.truncate(len);
+    ScalarVector(res)
+  }
+
+  pub(crate) fn len(&self) -> usize {
+    self.0.len()
+  }
+
+  pub(crate) fn sum(mut self) -> Scalar {
+    self.0.drain(..).sum()
+  }
+
+  pub(crate) fn inner_product(self, vector: &Self) -> Scalar {
+    (self * vector).sum()
+  }
+
+  pub(crate) fn weighted_inner_product(self, vector: &Self, y: &Self) -> Scalar {
+    (self * vector * y).sum()
+  }
+
+  pub(crate) fn split(mut self) -> (Self, Self) {
+    debug_assert!(self.len() > 1);
+    let r = self.0.split_off(self.0.len() / 2);
+    debug_assert_eq!(self.len(), r.len());
+    (self, ScalarVector(r))
+  }
+}

coins/monero/ringct/bulletproofs/src/tests/mod.rs

@@ -0,0 +1,105 @@
+use hex_literal::hex;
+use rand_core::OsRng;
+
+use curve25519_dalek::scalar::Scalar;
+
+use monero_io::decompress_point;
+use monero_primitives::Commitment;
+
+use crate::{batch_verifier::BatchVerifier, original::OriginalStruct, Bulletproof, BulletproofError};
+
+mod plus;
+
+#[test]
+fn bulletproofs_vector() {
+  let scalar = |scalar| Scalar::from_canonical_bytes(scalar).unwrap();
+  let point = |point| decompress_point(point).unwrap();
+
+  // Generated from Monero
+  assert!(Bulletproof::Original(OriginalStruct {
+    A: point(hex!("ef32c0b9551b804decdcb107eb22aa715b7ce259bf3c5cac20e24dfa6b28ac71")),
+    S: point(hex!("e1285960861783574ee2b689ae53622834eb0b035d6943103f960cd23e063fa0")),
+    T1: point(hex!("4ea07735f184ba159d0e0eb662bac8cde3eb7d39f31e567b0fbda3aa23fe5620")),
+    T2: point(hex!("b8390aa4b60b255630d40e592f55ec6b7ab5e3a96bfcdcd6f1cd1d2fc95f441e")),
+    tau_x: scalar(hex!("5957dba8ea9afb23d6e81cc048a92f2d502c10c749dc1b2bd148ae8d41ec7107")),
+    mu: scalar(hex!("923023b234c2e64774b820b4961f7181f6c1dc152c438643e5a25b0bf271bc02")),
+    L: vec![
+      point(hex!("c45f656316b9ebf9d357fb6a9f85b5f09e0b991dd50a6e0ae9b02de3946c9d99")),
+      point(hex!("9304d2bf0f27183a2acc58cc755a0348da11bd345485fda41b872fee89e72aac")),
+      point(hex!("1bb8b71925d155dd9569f64129ea049d6149fdc4e7a42a86d9478801d922129b")),
+      point(hex!("5756a7bf887aa72b9a952f92f47182122e7b19d89e5dd434c747492b00e1c6b7")),
+      point(hex!("6e497c910d102592830555356af5ff8340e8d141e3fb60ea24cfa587e964f07d")),
+      point(hex!("f4fa3898e7b08e039183d444f3d55040f3c790ed806cb314de49f3068bdbb218")),
+      point(hex!("0bbc37597c3ead517a3841e159c8b7b79a5ceaee24b2a9a20350127aab428713")),
+    ],
+    R: vec![
+      point(hex!("609420ba1702781692e84accfd225adb3d077aedc3cf8125563400466b52dbd9")),
+      point(hex!("fb4e1d079e7a2b0ec14f7e2a3943bf50b6d60bc346a54fcf562fb234b342abf8")),
+      point(hex!("6ae3ac97289c48ce95b9c557289e82a34932055f7f5e32720139824fe81b12e5")),
+      point(hex!("d071cc2ffbdab2d840326ad15f68c01da6482271cae3cf644670d1632f29a15c")),
+      point(hex!("e52a1754b95e1060589ba7ce0c43d0060820ebfc0d49dc52884bc3c65ad18af5")),
+      point(hex!("41573b06140108539957df71aceb4b1816d2409ce896659aa5c86f037ca5e851")),
+      point(hex!("a65970b2cc3c7b08b2b5b739dbc8e71e646783c41c625e2a5b1535e3d2e0f742")),
+    ],
+    a: scalar(hex!("0077c5383dea44d3cd1bc74849376bd60679612dc4b945255822457fa0c0a209")),
+    b: scalar(hex!("fe80cf5756473482581e1d38644007793ddc66fdeb9404ec1689a907e4863302")),
+    t: scalar(hex!("40dfb08e09249040df997851db311bd6827c26e87d6f0f332c55be8eef10e603"))
+  })
+  .verify(
+    &mut OsRng,
+    &[
+      // For some reason, these vectors are * INV_EIGHT
+      point(hex!("8e8f23f315edae4f6c2f948d9a861e0ae32d356b933cd11d2f0e031ac744c41f"))
+        .mul_by_cofactor(),
+      point(hex!("2829cbd025aa54cd6e1b59a032564f22f0b2e5627f7f2c4297f90da438b5510f"))
+        .mul_by_cofactor(),
+    ]
+  ));
+}
+
+macro_rules! bulletproofs_tests {
+  ($name: ident, $max: ident, $plus: literal) => {
+    #[test]
+    fn $name() {
+      // Create Bulletproofs for all possible output quantities
+      let mut verifier = BatchVerifier::new();
+      for i in 1 ..= 16 {
+        let commitments = (1 ..= i)
+          .map(|i| Commitment::new(Scalar::random(&mut OsRng), u64::try_from(i).unwrap()))
+          .collect::<Vec<_>>();
+
+        let bp = if $plus {
+          Bulletproof::prove_plus(&mut OsRng, commitments.clone()).unwrap()
+        } else {
+          Bulletproof::prove(&mut OsRng, &commitments).unwrap()
+        };
+
+        let commitments = commitments.iter().map(Commitment::calculate).collect::<Vec<_>>();
+        assert!(bp.verify(&mut OsRng, &commitments));
+        assert!(bp.batch_verify(&mut OsRng, &mut verifier, &commitments));
+      }
+      assert!(verifier.verify());
+    }
+
+    #[test]
+    fn $max() {
+      // Check Bulletproofs errors if we try to prove for too many outputs
+      let mut commitments = vec![];
+      for _ in 0 .. 17 {
+        commitments.push(Commitment::new(Scalar::ZERO, 0));
+      }
+      assert_eq!(
+        (if $plus {
+          Bulletproof::prove_plus(&mut OsRng, commitments)
+        } else {
+          Bulletproof::prove(&mut OsRng, &commitments)
+        })
+        .unwrap_err(),
+        BulletproofError::TooManyCommitments,
+      );
+    }
+  };
+}
+
+bulletproofs_tests!(bulletproofs, bulletproofs_max, false);
+bulletproofs_tests!(bulletproofs_plus, bulletproofs_plus_max, true);

coins/monero/ringct/bulletproofs/src/tests/plus/aggregate_range_proof.rs

@@ -0,0 +1,28 @@
+use rand_core::{RngCore, OsRng};
+
+use curve25519_dalek::Scalar;
+
+use monero_primitives::Commitment;
+
+use crate::{
+  batch_verifier::BulletproofsPlusBatchVerifier,
+  plus::aggregate_range_proof::{AggregateRangeStatement, AggregateRangeWitness},
+};
+
+#[test]
+fn test_aggregate_range_proof() {
+  let mut verifier = BulletproofsPlusBatchVerifier::default();
+  for m in 1 ..= 16 {
+    let mut commitments = vec![];
+    for _ in 0 .. m {
+      commitments.push(Commitment::new(Scalar::random(&mut OsRng), OsRng.next_u64()));
+    }
+    let commitment_points = commitments.iter().map(Commitment::calculate).collect();
+    let statement = AggregateRangeStatement::new(commitment_points).unwrap();
+    let witness = AggregateRangeWitness::new(commitments).unwrap();
+
+    let proof = statement.clone().prove(&mut OsRng, &witness).unwrap();
+    statement.verify(&mut OsRng, &mut verifier, proof);
+  }
+  assert!(verifier.verify());
+}

coins/monero/ringct/bulletproofs/src/tests/plus/mod.rs

@@ -0,0 +1,4 @@
+#[cfg(test)]
+mod weighted_inner_product;
+#[cfg(test)]
+mod aggregate_range_proof;

coins/monero/ringct/bulletproofs/src/tests/plus/weighted_inner_product.rs

@@ -0,0 +1,82 @@
+// The inner product relation is P = sum(g_bold * a, h_bold * b, g * (a * y * b), h * alpha)
+
+use rand_core::OsRng;
+
+use curve25519_dalek::{traits::Identity, scalar::Scalar, edwards::EdwardsPoint};
+
+use crate::{
+  batch_verifier::BulletproofsPlusBatchVerifier,
+  plus::{
+    ScalarVector, PointVector, GeneratorsList, BpPlusGenerators,
+    weighted_inner_product::{WipStatement, WipWitness},
+  },
+};
+
+#[test]
+fn test_zero_weighted_inner_product() {
+  #[allow(non_snake_case)]
+  let P = EdwardsPoint::identity();
+  let y = Scalar::random(&mut OsRng);
+
+  let generators = BpPlusGenerators::new().reduce(1);
+  let statement = WipStatement::new(generators, P, y);
+  let witness = WipWitness::new(ScalarVector::new(1), ScalarVector::new(1), Scalar::ZERO).unwrap();
+
+  let transcript = Scalar::random(&mut OsRng);
+  let proof = statement.clone().prove(&mut OsRng, transcript, &witness).unwrap();
+
+  let mut verifier = BulletproofsPlusBatchVerifier::default();
+  statement.verify(&mut OsRng, &mut verifier, transcript, proof);
+  assert!(verifier.verify());
+}
+
+#[test]
+fn test_weighted_inner_product() {
+  // P = sum(g_bold * a, h_bold * b, g * (a * y * b), h * alpha)
+  let mut verifier = BulletproofsPlusBatchVerifier::default();
+  let generators = BpPlusGenerators::new();
+  for i in [1, 2, 4, 8, 16, 32] {
+    let generators = generators.reduce(i);
+    let g = BpPlusGenerators::g();
+    let h = BpPlusGenerators::h();
+    assert_eq!(generators.len(), i);
+    let mut g_bold = vec![];
+    let mut h_bold = vec![];
+    for i in 0 .. i {
+      g_bold.push(generators.generator(GeneratorsList::GBold, i));
+      h_bold.push(generators.generator(GeneratorsList::HBold, i));
+    }
+    let g_bold = PointVector(g_bold);
+    let h_bold = PointVector(h_bold);
+
+    let mut a = ScalarVector::new(i);
+    let mut b = ScalarVector::new(i);
+    let alpha = Scalar::random(&mut OsRng);
+
+    let y = Scalar::random(&mut OsRng);
+    let mut y_vec = ScalarVector::new(g_bold.len());
+    y_vec[0] = y;
+    for i in 1 .. y_vec.len() {
+      y_vec[i] = y_vec[i - 1] * y;
+    }
+
+    for i in 0 .. i {
+      a[i] = Scalar::random(&mut OsRng);
+      b[i] = Scalar::random(&mut OsRng);
+    }
+
+    #[allow(non_snake_case)]
+    let P = g_bold.multiexp(&a) +
+      h_bold.multiexp(&b) +
+      (g * a.clone().weighted_inner_product(&b, &y_vec)) +
+      (h * alpha);
+
+    let statement = WipStatement::new(generators, P, y);
+    let witness = WipWitness::new(a, b, alpha).unwrap();
+
+    let transcript = Scalar::random(&mut OsRng);
+    let proof = statement.clone().prove(&mut OsRng, transcript, &witness).unwrap();
+    statement.verify(&mut OsRng, &mut verifier, transcript, proof);
+  }
+  assert!(verifier.verify());
+}