From a4f020f30d99da42c5e2a418cbf6a864251b2962 Mon Sep 17 00:00:00 2001
From: DaniPopes <57450786+DaniPopes@users.noreply.github.com>
Date: Fri, 10 May 2024 10:27:27 +0200
Subject: [PATCH 1/2] fix(precompile): blst dangling pointers, cleanup

---
 crates/precompile/src/bls12_381/g1.rs         | 13 ++----
 crates/precompile/src/bls12_381/g1_add.rs     | 22 +++------
 crates/precompile/src/bls12_381/g1_msm.rs     | 19 +++-----
 crates/precompile/src/bls12_381/g1_mul.rs     | 22 +++------
 crates/precompile/src/bls12_381/g2.rs         | 46 ++++++++-----------
 crates/precompile/src/bls12_381/g2_add.rs     | 22 +++------
 crates/precompile/src/bls12_381/g2_msm.rs     | 18 +++-----
 crates/precompile/src/bls12_381/g2_mul.rs     | 22 +++------
 .../precompile/src/bls12_381/map_fp2_to_g2.rs | 30 ++++--------
 .../precompile/src/bls12_381/map_fp_to_g1.rs  | 26 ++++-------
 crates/precompile/src/bls12_381/msm.rs        | 10 ++--
 crates/precompile/src/bls12_381/pairing.rs    | 12 ++---
 crates/precompile/src/bls12_381/utils.rs      | 22 ++++-----
 13 files changed, 101 insertions(+), 183 deletions(-)

diff --git a/crates/precompile/src/bls12_381/g1.rs b/crates/precompile/src/bls12_381/g1.rs
index 28e5a845d4..ca0b067047 100644
--- a/crates/precompile/src/bls12_381/g1.rs
+++ b/crates/precompile/src/bls12_381/g1.rs
@@ -1,8 +1,7 @@
+use super::utils::{fp_to_bytes, remove_padding, PADDED_FP_LENGTH};
 use blst::{blst_fp_from_bendian, blst_p1_affine, blst_p1_affine_in_g1};
 use revm_primitives::{Bytes, PrecompileError};
 
-use super::utils::{fp_to_bytes, remove_padding, PADDED_FP_LENGTH};
-
 /// Length of each of the elements in a g1 operation input.
 pub(super) const G1_INPUT_ITEM_LENGTH: usize = 128;
 /// Output length of a g1 operation.
@@ -20,7 +19,7 @@ pub(super) fn encode_g1_point(input: *const blst_p1_affine) -> Bytes {
 }
 
 /// Extracts a G1 point in Affine format from a 128 byte slice representation.
-pub(super) fn extract_g1_input(input: &[u8]) -> Result<*const blst_p1_affine, PrecompileError> {
+pub(super) fn extract_g1_input(input: &[u8]) -> Result<blst_p1_affine, PrecompileError> {
     if input.len() != G1_INPUT_ITEM_LENGTH {
         return Err(PrecompileError::Other(format!(
             "Input should be {G1_INPUT_ITEM_LENGTH} bits, was {}",
@@ -39,10 +38,8 @@ pub(super) fn extract_g1_input(input: &[u8]) -> Result<*const blst_p1_affine, Pr
     }
 
     // SAFETY: out is a blst value.
-    unsafe {
-        if !blst_p1_affine_in_g1(&out) {
-            return Err(PrecompileError::Other("Element not in G1".to_string()));
-        }
+    if unsafe { !blst_p1_affine_in_g1(&out) } {
+        return Err(PrecompileError::Other("Element not in G1".to_string()));
     }
-    Ok(&mut out as *const _)
+    Ok(out)
 }
diff --git a/crates/precompile/src/bls12_381/g1_add.rs b/crates/precompile/src/bls12_381/g1_add.rs
index e3adba016a..ee3d308e81 100644
--- a/crates/precompile/src/bls12_381/g1_add.rs
+++ b/crates/precompile/src/bls12_381/g1_add.rs
@@ -1,12 +1,10 @@
+use super::g1::{encode_g1_point, extract_g1_input, G1_INPUT_ITEM_LENGTH};
+use crate::{u64_to_address, PrecompileWithAddress};
 use blst::{
     blst_p1, blst_p1_add_or_double_affine, blst_p1_affine, blst_p1_from_affine, blst_p1_to_affine,
 };
 use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
 
-use crate::{u64_to_address, PrecompileWithAddress};
-
-use super::g1::{encode_g1_point, extract_g1_input, G1_INPUT_ITEM_LENGTH};
-
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_G1ADD precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
     PrecompileWithAddress(u64_to_address(ADDRESS), Precompile::Standard(g1_add));
@@ -35,26 +33,20 @@ fn g1_add(input: &Bytes, gas_limit: u64) -> PrecompileResult {
         )));
     }
 
-    let a_aff = extract_g1_input(&input[..G1_INPUT_ITEM_LENGTH])?;
-    let b_aff = extract_g1_input(&input[G1_INPUT_ITEM_LENGTH..])?;
+    let a_aff = &extract_g1_input(&input[..G1_INPUT_ITEM_LENGTH])?;
+    let b_aff = &extract_g1_input(&input[G1_INPUT_ITEM_LENGTH..])?;
 
     let mut b = blst_p1::default();
     // SAFETY: b and b_aff are blst values.
-    unsafe {
-        blst_p1_from_affine(&mut b, b_aff);
-    }
+    unsafe { blst_p1_from_affine(&mut b, b_aff) };
 
     let mut p = blst_p1::default();
     // SAFETY: p, b and a_aff are blst values.
-    unsafe {
-        blst_p1_add_or_double_affine(&mut p, &b, a_aff);
-    }
+    unsafe { blst_p1_add_or_double_affine(&mut p, &b, a_aff) };
 
     let mut p_aff = blst_p1_affine::default();
     // SAFETY: p_aff and p are blst values.
-    unsafe {
-        blst_p1_to_affine(&mut p_aff, &p);
-    }
+    unsafe { blst_p1_to_affine(&mut p_aff, &p) };
 
     let out = encode_g1_point(&p_aff);
     Ok((BASE_GAS_FEE, out))
diff --git a/crates/precompile/src/bls12_381/g1_msm.rs b/crates/precompile/src/bls12_381/g1_msm.rs
index a339d86039..c02f055bb2 100644
--- a/crates/precompile/src/bls12_381/g1_msm.rs
+++ b/crates/precompile/src/bls12_381/g1_msm.rs
@@ -1,14 +1,12 @@
-use blst::{blst_p1, blst_p1_affine, blst_p1_from_affine, blst_p1_to_affine, p1_affines};
-use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
-
-use crate::{u64_to_address, PrecompileWithAddress};
-
 use super::{
     g1::{encode_g1_point, extract_g1_input, G1_INPUT_ITEM_LENGTH},
     g1_mul,
     msm::msm_required_gas,
     utils::{extract_scalar_input, NBITS, SCALAR_LENGTH},
 };
+use crate::{u64_to_address, PrecompileWithAddress};
+use blst::{blst_p1, blst_p1_affine, blst_p1_from_affine, blst_p1_to_affine, p1_affines};
+use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
 
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_G1MSM precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
@@ -43,15 +41,12 @@ fn g1_msm(input: &Bytes, gas_limit: u64) -> PrecompileResult {
     let mut g1_points: Vec<blst_p1> = Vec::with_capacity(k);
     let mut scalars: Vec<u8> = Vec::with_capacity(k * SCALAR_LENGTH);
     for i in 0..k {
-        let p0_aff = extract_g1_input(
+        let p0_aff = &extract_g1_input(
             &input[i * g1_mul::INPUT_LENGTH..i * g1_mul::INPUT_LENGTH + G1_INPUT_ITEM_LENGTH],
         )?;
         let mut p0 = blst_p1::default();
         // SAFETY: p0 and p0_aff are blst values.
-        unsafe {
-            blst_p1_from_affine(&mut p0, p0_aff);
-        }
-
+        unsafe { blst_p1_from_affine(&mut p0, p0_aff) };
         g1_points.push(p0);
 
         scalars.extend_from_slice(
@@ -68,9 +63,7 @@ fn g1_msm(input: &Bytes, gas_limit: u64) -> PrecompileResult {
 
     let mut multiexp_aff = blst_p1_affine::default();
     // SAFETY: multiexp_aff and multiexp are blst values.
-    unsafe {
-        blst_p1_to_affine(&mut multiexp_aff, &multiexp);
-    }
+    unsafe { blst_p1_to_affine(&mut multiexp_aff, &multiexp) };
 
     let out = encode_g1_point(&multiexp_aff);
     Ok((required_gas, out))
diff --git a/crates/precompile/src/bls12_381/g1_mul.rs b/crates/precompile/src/bls12_381/g1_mul.rs
index 171de875c8..d8d5e10bf3 100644
--- a/crates/precompile/src/bls12_381/g1_mul.rs
+++ b/crates/precompile/src/bls12_381/g1_mul.rs
@@ -1,12 +1,10 @@
-use blst::{blst_p1, blst_p1_affine, blst_p1_from_affine, blst_p1_mult, blst_p1_to_affine};
-use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
-
-use crate::{u64_to_address, PrecompileWithAddress};
-
 use super::{
     g1::{encode_g1_point, extract_g1_input, G1_INPUT_ITEM_LENGTH},
     utils::{extract_scalar_input, NBITS},
 };
+use crate::{u64_to_address, PrecompileWithAddress};
+use blst::{blst_p1, blst_p1_affine, blst_p1_from_affine, blst_p1_mult, blst_p1_to_affine};
+use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
 
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_G1MUL precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
@@ -36,25 +34,19 @@ pub fn g1_mul(input: &Bytes, gas_limit: u64) -> PrecompileResult {
         )));
     }
 
-    let p0_aff = extract_g1_input(&input[..G1_INPUT_ITEM_LENGTH])?;
+    let p0_aff = &extract_g1_input(&input[..G1_INPUT_ITEM_LENGTH])?;
     let mut p0 = blst_p1::default();
     // SAFETY: p0 and p0_aff are blst values.
-    unsafe {
-        blst_p1_from_affine(&mut p0, p0_aff);
-    }
+    unsafe { blst_p1_from_affine(&mut p0, p0_aff) };
 
     let input_scalar0 = extract_scalar_input(&input[G1_INPUT_ITEM_LENGTH..])?;
 
     let mut p = blst_p1::default();
     // SAFETY: input_scalar0.b has fixed size, p and p0 are blst values.
-    unsafe {
-        blst_p1_mult(&mut p, &p0, input_scalar0.b.as_ptr(), NBITS);
-    }
+    unsafe { blst_p1_mult(&mut p, &p0, input_scalar0.b.as_ptr(), NBITS) };
     let mut p_aff = blst_p1_affine::default();
     // SAFETY: p_aff and p are blst values.
-    unsafe {
-        blst_p1_to_affine(&mut p_aff, &p);
-    }
+    unsafe { blst_p1_to_affine(&mut p_aff, &p) };
 
     let out = encode_g1_point(&p_aff);
     Ok((BASE_GAS_FEE, out))
diff --git a/crates/precompile/src/bls12_381/g2.rs b/crates/precompile/src/bls12_381/g2.rs
index 0c861e7f7d..43386d90aa 100644
--- a/crates/precompile/src/bls12_381/g2.rs
+++ b/crates/precompile/src/bls12_381/g2.rs
@@ -1,37 +1,33 @@
+use super::utils::{fp_to_bytes, remove_padding, FP_LENGTH, PADDED_FP_LENGTH};
 use blst::{blst_fp_from_bendian, blst_p2_affine, blst_p2_affine_in_g2};
 use revm_primitives::{Bytes, PrecompileError};
 
-use super::utils::{fp_to_bytes, remove_padding, FP_LENGTH, PADDED_FP_LENGTH};
-
 /// Length of each of the elements in a g2 operation input.
 pub(super) const G2_INPUT_ITEM_LENGTH: usize = 256;
 /// Output length of a g2 operation.
 const G2_OUTPUT_LENGTH: usize = 256;
 
 /// Encodes a G2 point in affine format into a byte slice with padded elements.
-pub(super) fn encode_g2_point(input: *const blst_p2_affine) -> Bytes {
+pub(super) fn encode_g2_point(input: &blst_p2_affine) -> Bytes {
     let mut out = vec![0u8; G2_OUTPUT_LENGTH];
-    // SAFETY: out comes from fixed length array, input is a blst value.
-    unsafe {
-        fp_to_bytes(&mut out[..PADDED_FP_LENGTH], &(*input).x.fp[0]);
-        fp_to_bytes(
-            &mut out[PADDED_FP_LENGTH..2 * PADDED_FP_LENGTH],
-            &(*input).x.fp[1],
-        );
-        fp_to_bytes(
-            &mut out[2 * PADDED_FP_LENGTH..3 * PADDED_FP_LENGTH],
-            &(*input).y.fp[0],
-        );
-        fp_to_bytes(
-            &mut out[3 * PADDED_FP_LENGTH..4 * PADDED_FP_LENGTH],
-            &(*input).y.fp[1],
-        );
-    }
+    fp_to_bytes(&mut out[..PADDED_FP_LENGTH], &input.x.fp[0]);
+    fp_to_bytes(
+        &mut out[PADDED_FP_LENGTH..2 * PADDED_FP_LENGTH],
+        &input.x.fp[1],
+    );
+    fp_to_bytes(
+        &mut out[2 * PADDED_FP_LENGTH..3 * PADDED_FP_LENGTH],
+        &input.y.fp[0],
+    );
+    fp_to_bytes(
+        &mut out[3 * PADDED_FP_LENGTH..4 * PADDED_FP_LENGTH],
+        &input.y.fp[1],
+    );
     out.into()
 }
 
 /// Extracts a G2 point in Affine format from a 256 byte slice representation.
-pub(super) fn extract_g2_input(input: &[u8]) -> Result<*const blst_p2_affine, PrecompileError> {
+pub(super) fn extract_g2_input(input: &[u8]) -> Result<blst_p2_affine, PrecompileError> {
     if input.len() != G2_INPUT_ITEM_LENGTH {
         return Err(PrecompileError::Other(format!(
             "Input should be {G2_INPUT_ITEM_LENGTH} bits, was {}",
@@ -39,7 +35,7 @@ pub(super) fn extract_g2_input(input: &[u8]) -> Result<*const blst_p2_affine, Pr
         )));
     }
 
-    let mut input_fps: [[u8; FP_LENGTH]; 4] = [[0; FP_LENGTH]; 4];
+    let mut input_fps: [&[u8; FP_LENGTH]; 4] = [&[0; FP_LENGTH]; 4];
     for i in 0..4 {
         input_fps[i] = remove_padding(&input[i * PADDED_FP_LENGTH..(i + 1) * PADDED_FP_LENGTH])?;
     }
@@ -54,11 +50,9 @@ pub(super) fn extract_g2_input(input: &[u8]) -> Result<*const blst_p2_affine, Pr
     }
 
     // SAFETY: out is a blst value.
-    unsafe {
-        if !blst_p2_affine_in_g2(&out) {
-            return Err(PrecompileError::Other("Element not in G2".to_string()));
-        }
+    if unsafe { !blst_p2_affine_in_g2(&out) } {
+        return Err(PrecompileError::Other("Element not in G2".to_string()));
     }
 
-    Ok(&mut out as *const _)
+    Ok(out)
 }
diff --git a/crates/precompile/src/bls12_381/g2_add.rs b/crates/precompile/src/bls12_381/g2_add.rs
index 2d7e95edf6..1a67597efb 100644
--- a/crates/precompile/src/bls12_381/g2_add.rs
+++ b/crates/precompile/src/bls12_381/g2_add.rs
@@ -1,12 +1,10 @@
+use super::g2::{encode_g2_point, extract_g2_input, G2_INPUT_ITEM_LENGTH};
+use crate::{u64_to_address, PrecompileWithAddress};
 use blst::{
     blst_p2, blst_p2_add_or_double_affine, blst_p2_affine, blst_p2_from_affine, blst_p2_to_affine,
 };
 use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
 
-use crate::{u64_to_address, PrecompileWithAddress};
-
-use super::g2::{encode_g2_point, extract_g2_input, G2_INPUT_ITEM_LENGTH};
-
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_G2ADD precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
     PrecompileWithAddress(u64_to_address(ADDRESS), Precompile::Standard(g2_add));
@@ -36,26 +34,20 @@ fn g2_add(input: &Bytes, gas_limit: u64) -> PrecompileResult {
         )));
     }
 
-    let a_aff = extract_g2_input(&input[..G2_INPUT_ITEM_LENGTH])?;
-    let b_aff = extract_g2_input(&input[G2_INPUT_ITEM_LENGTH..])?;
+    let a_aff = &extract_g2_input(&input[..G2_INPUT_ITEM_LENGTH])?;
+    let b_aff = &extract_g2_input(&input[G2_INPUT_ITEM_LENGTH..])?;
 
     let mut b = blst_p2::default();
     // SAFETY: b and b_aff are blst values.
-    unsafe {
-        blst_p2_from_affine(&mut b, b_aff);
-    }
+    unsafe { blst_p2_from_affine(&mut b, b_aff) };
 
     let mut p = blst_p2::default();
     // SAFETY: p, b and a_aff are blst values.
-    unsafe {
-        blst_p2_add_or_double_affine(&mut p, &b, a_aff);
-    }
+    unsafe { blst_p2_add_or_double_affine(&mut p, &b, a_aff) };
 
     let mut p_aff = blst_p2_affine::default();
     // SAFETY: p_aff and p are blst values.
-    unsafe {
-        blst_p2_to_affine(&mut p_aff, &p);
-    }
+    unsafe { blst_p2_to_affine(&mut p_aff, &p) };
 
     let out = encode_g2_point(&p_aff);
     Ok((BASE_GAS_FEE, out))
diff --git a/crates/precompile/src/bls12_381/g2_msm.rs b/crates/precompile/src/bls12_381/g2_msm.rs
index 8ea82c2024..a17c5c47de 100644
--- a/crates/precompile/src/bls12_381/g2_msm.rs
+++ b/crates/precompile/src/bls12_381/g2_msm.rs
@@ -1,14 +1,12 @@
-use blst::{blst_p2, blst_p2_affine, blst_p2_from_affine, blst_p2_to_affine, p2_affines};
-use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
-
-use crate::{u64_to_address, PrecompileWithAddress};
-
 use super::{
     g2::{encode_g2_point, extract_g2_input, G2_INPUT_ITEM_LENGTH},
     g2_mul,
     msm::msm_required_gas,
     utils::{extract_scalar_input, NBITS, SCALAR_LENGTH},
 };
+use crate::{u64_to_address, PrecompileWithAddress};
+use blst::{blst_p2, blst_p2_affine, blst_p2_from_affine, blst_p2_to_affine, p2_affines};
+use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
 
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_G2MSM precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
@@ -43,14 +41,12 @@ fn g2_msm(input: &Bytes, gas_limit: u64) -> PrecompileResult {
     let mut g2_points: Vec<blst_p2> = Vec::with_capacity(k);
     let mut scalars: Vec<u8> = Vec::with_capacity(k * SCALAR_LENGTH);
     for i in 0..k {
-        let p0_aff = extract_g2_input(
+        let p0_aff = &extract_g2_input(
             &input[i * g2_mul::INPUT_LENGTH..i * g2_mul::INPUT_LENGTH + G2_INPUT_ITEM_LENGTH],
         )?;
         let mut p0 = blst_p2::default();
         // SAFETY: p0 and p0_aff are blst values.
-        unsafe {
-            blst_p2_from_affine(&mut p0, p0_aff);
-        }
+        unsafe { blst_p2_from_affine(&mut p0, p0_aff) };
 
         g2_points.push(p0);
 
@@ -68,9 +64,7 @@ fn g2_msm(input: &Bytes, gas_limit: u64) -> PrecompileResult {
 
     let mut multiexp_aff = blst_p2_affine::default();
     // SAFETY: multiexp_aff and multiexp are blst values.
-    unsafe {
-        blst_p2_to_affine(&mut multiexp_aff, &multiexp);
-    }
+    unsafe { blst_p2_to_affine(&mut multiexp_aff, &multiexp) };
 
     let out = encode_g2_point(&multiexp_aff);
     Ok((required_gas, out))
diff --git a/crates/precompile/src/bls12_381/g2_mul.rs b/crates/precompile/src/bls12_381/g2_mul.rs
index be3f4f9f14..0efd3595e7 100644
--- a/crates/precompile/src/bls12_381/g2_mul.rs
+++ b/crates/precompile/src/bls12_381/g2_mul.rs
@@ -1,12 +1,10 @@
-use blst::{blst_p2, blst_p2_affine, blst_p2_from_affine, blst_p2_mult, blst_p2_to_affine};
-use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
-
-use crate::{u64_to_address, PrecompileWithAddress};
-
 use super::{
     g2::{encode_g2_point, extract_g2_input, G2_INPUT_ITEM_LENGTH},
     utils::{extract_scalar_input, NBITS},
 };
+use crate::{u64_to_address, PrecompileWithAddress};
+use blst::{blst_p2, blst_p2_affine, blst_p2_from_affine, blst_p2_mult, blst_p2_to_affine};
+use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
 
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_G2MUL precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
@@ -36,25 +34,19 @@ fn g2_mul(input: &Bytes, gas_limit: u64) -> PrecompileResult {
         )));
     }
 
-    let p0_aff = extract_g2_input(&input[..G2_INPUT_ITEM_LENGTH])?;
+    let p0_aff = &extract_g2_input(&input[..G2_INPUT_ITEM_LENGTH])?;
     let mut p0 = blst_p2::default();
     // SAFETY: p0 and p0_aff are blst values.
-    unsafe {
-        blst_p2_from_affine(&mut p0, p0_aff);
-    }
+    unsafe { blst_p2_from_affine(&mut p0, p0_aff) };
 
     let input_scalar0 = extract_scalar_input(&input[G2_INPUT_ITEM_LENGTH..])?;
 
     let mut p = blst_p2::default();
     // SAFETY: input_scalar0.b has fixed size, p and p0 are blst values.
-    unsafe {
-        blst_p2_mult(&mut p, &p0, input_scalar0.b.as_ptr(), NBITS);
-    }
+    unsafe { blst_p2_mult(&mut p, &p0, input_scalar0.b.as_ptr(), NBITS) };
     let mut p_aff = blst_p2_affine::default();
     // SAFETY: p_aff and p are blst values.
-    unsafe {
-        blst_p2_to_affine(&mut p_aff, &p);
-    }
+    unsafe { blst_p2_to_affine(&mut p_aff, &p) };
 
     let out = encode_g2_point(&p_aff);
     Ok((BASE_GAS_FEE, out))
diff --git a/crates/precompile/src/bls12_381/map_fp2_to_g2.rs b/crates/precompile/src/bls12_381/map_fp2_to_g2.rs
index 6448dda6f6..fffe73ba83 100644
--- a/crates/precompile/src/bls12_381/map_fp2_to_g2.rs
+++ b/crates/precompile/src/bls12_381/map_fp2_to_g2.rs
@@ -1,16 +1,14 @@
+use super::{
+    g2::encode_g2_point,
+    utils::{remove_padding, PADDED_FP2_LENGTH, PADDED_FP_LENGTH},
+};
+use crate::{u64_to_address, PrecompileWithAddress};
 use blst::{
     blst_fp, blst_fp2, blst_fp_from_bendian, blst_map_to_g2, blst_p2, blst_p2_affine,
     blst_p2_to_affine,
 };
 use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
 
-use crate::{u64_to_address, PrecompileWithAddress};
-
-use super::{
-    g2::encode_g2_point,
-    utils::{remove_padding, PADDED_FP2_LENGTH, PADDED_FP_LENGTH},
-};
-
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_MAP_FP2_TO_G2 precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
     PrecompileWithAddress(u64_to_address(ADDRESS), Precompile::Standard(map_fp2_to_g2));
@@ -42,28 +40,20 @@ fn map_fp2_to_g2(input: &Bytes, gas_limit: u64) -> PrecompileResult {
     let mut fp_x = blst_fp::default();
     let mut fp_y = blst_fp::default();
     // SAFETY: input_p0_x has fixed length, fp_x is a blst value.
-    unsafe {
-        blst_fp_from_bendian(&mut fp_x, input_p0_x.as_ptr());
-    }
+    unsafe { blst_fp_from_bendian(&mut fp_x, input_p0_x.as_ptr()) };
     // SAFETY: input_p0_y has fixed length, fp_y is a blst value.
-    unsafe {
-        blst_fp_from_bendian(&mut fp_y, input_p0_y.as_ptr());
-    }
+    unsafe { blst_fp_from_bendian(&mut fp_y, input_p0_y.as_ptr()) };
     fp2.fp[0] = fp_x;
     fp2.fp[1] = fp_y;
 
     let mut p = blst_p2::default();
     // SAFETY: p and fp2 are blst values.
-    unsafe {
-        // third argument is unused if null.
-        blst_map_to_g2(&mut p, &fp2, std::ptr::null());
-    }
+    // third argument is unused if null.
+    unsafe { blst_map_to_g2(&mut p, &fp2, core::ptr::null()) };
 
     let mut p_aff = blst_p2_affine::default();
     // SAFETY: p_aff and p are blst values.
-    unsafe {
-        blst_p2_to_affine(&mut p_aff, &p);
-    }
+    unsafe { blst_p2_to_affine(&mut p_aff, &p) };
 
     let out = encode_g2_point(&p_aff);
     Ok((BASE_GAS_FEE, out))
diff --git a/crates/precompile/src/bls12_381/map_fp_to_g1.rs b/crates/precompile/src/bls12_381/map_fp_to_g1.rs
index f0d273f3bf..795402a518 100644
--- a/crates/precompile/src/bls12_381/map_fp_to_g1.rs
+++ b/crates/precompile/src/bls12_381/map_fp_to_g1.rs
@@ -1,14 +1,12 @@
-use blst::{
-    blst_fp, blst_fp_from_bendian, blst_map_to_g1, blst_p1, blst_p1_affine, blst_p1_to_affine,
-};
-use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
-
-use crate::{u64_to_address, PrecompileWithAddress};
-
 use super::{
     g1::encode_g1_point,
     utils::{remove_padding, PADDED_FP_LENGTH},
 };
+use crate::{u64_to_address, PrecompileWithAddress};
+use blst::{
+    blst_fp, blst_fp_from_bendian, blst_map_to_g1, blst_p1, blst_p1_affine, blst_p1_to_affine,
+};
+use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult};
 
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_MAP_FP_TO_G1 precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
@@ -38,22 +36,16 @@ fn map_fp_to_g1(input: &Bytes, gas_limit: u64) -> PrecompileResult {
     let mut fp = blst_fp::default();
 
     // SAFETY: input_p0 has fixed length, fp is a blst value.
-    unsafe {
-        blst_fp_from_bendian(&mut fp, input_p0.as_ptr());
-    }
+    unsafe { blst_fp_from_bendian(&mut fp, input_p0.as_ptr()) };
 
     let mut p = blst_p1::default();
     // SAFETY: p and fp are blst values.
-    unsafe {
-        // third argument is unused if null.
-        blst_map_to_g1(&mut p, &fp, std::ptr::null());
-    }
+    // third argument is unused if null.
+    unsafe { blst_map_to_g1(&mut p, &fp, core::ptr::null()) };
 
     let mut p_aff = blst_p1_affine::default();
     // SAFETY: p_aff and p are blst values.
-    unsafe {
-        blst_p1_to_affine(&mut p_aff, &p);
-    }
+    unsafe { blst_p1_to_affine(&mut p_aff, &p) };
 
     let out = encode_g1_point(&p_aff);
     Ok((MAP_FP_TO_G1_BASE, out))
diff --git a/crates/precompile/src/bls12_381/msm.rs b/crates/precompile/src/bls12_381/msm.rs
index e26ea3ebb2..9ddeedc015 100644
--- a/crates/precompile/src/bls12_381/msm.rs
+++ b/crates/precompile/src/bls12_381/msm.rs
@@ -1,7 +1,8 @@
 /// Amount used to calculate the multi-scalar-multiplication discount.
 const MSM_MULTIPLIER: u64 = 1000;
+
 /// Table of gas discounts for multi-scalar-multiplication operations.
-const MSM_DISCOUNT_TABLE: [u64; 128] = [
+static MSM_DISCOUNT_TABLE: [u16; 128] = [
     1200, 888, 764, 641, 594, 547, 500, 453, 438, 423, 408, 394, 379, 364, 349, 334, 330, 326, 322,
     318, 314, 310, 306, 302, 298, 294, 289, 285, 281, 277, 273, 269, 268, 266, 265, 263, 262, 260,
     259, 257, 256, 254, 253, 251, 250, 248, 247, 245, 244, 242, 241, 239, 238, 236, 235, 233, 232,
@@ -18,11 +19,8 @@ pub(super) fn msm_required_gas(k: usize, multiplication_cost: u64) -> u64 {
         return 0;
     }
 
-    let discount = if k < MSM_DISCOUNT_TABLE.len() {
-        MSM_DISCOUNT_TABLE[k - 1]
-    } else {
-        MSM_DISCOUNT_TABLE[MSM_DISCOUNT_TABLE.len() - 1]
-    };
+    let index = core::cmp::min(k - 1, MSM_DISCOUNT_TABLE.len() - 1);
+    let discount = MSM_DISCOUNT_TABLE[index] as u64;
 
     (k as u64 * discount * multiplication_cost) / MSM_MULTIPLIER
 }
diff --git a/crates/precompile/src/bls12_381/pairing.rs b/crates/precompile/src/bls12_381/pairing.rs
index 2cd5cf9a6d..fb83e44807 100644
--- a/crates/precompile/src/bls12_381/pairing.rs
+++ b/crates/precompile/src/bls12_381/pairing.rs
@@ -1,12 +1,10 @@
-use blst::{blst_final_exp, blst_fp12, blst_fp12_is_one, blst_fp12_mul, blst_miller_loop};
-use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult, B256};
-
-use crate::{u64_to_address, PrecompileWithAddress};
-
 use super::{
     g1::{extract_g1_input, G1_INPUT_ITEM_LENGTH},
     g2::{extract_g2_input, G2_INPUT_ITEM_LENGTH},
 };
+use crate::{u64_to_address, PrecompileWithAddress};
+use blst::{blst_final_exp, blst_fp12, blst_fp12_is_one, blst_fp12_mul, blst_miller_loop};
+use revm_primitives::{Bytes, Precompile, PrecompileError, PrecompileResult, B256};
 
 /// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_PAIRING precompile.
 pub const PRECOMPILE: PrecompileWithAddress =
@@ -49,9 +47,9 @@ fn pairing(input: &Bytes, gas_limit: u64) -> PrecompileResult {
     let mut acc = blst_fp12::default();
     for i in 0..k {
         let p1_aff =
-            extract_g1_input(&input[i * INPUT_LENGTH..i * INPUT_LENGTH + G1_INPUT_ITEM_LENGTH])?;
+            &extract_g1_input(&input[i * INPUT_LENGTH..i * INPUT_LENGTH + G1_INPUT_ITEM_LENGTH])?;
 
-        let p2_aff = extract_g2_input(
+        let p2_aff = &extract_g2_input(
             &input[i * INPUT_LENGTH + G1_INPUT_ITEM_LENGTH
                 ..i * INPUT_LENGTH + G1_INPUT_ITEM_LENGTH + G2_INPUT_ITEM_LENGTH],
         )?;
diff --git a/crates/precompile/src/bls12_381/utils.rs b/crates/precompile/src/bls12_381/utils.rs
index 38673d66b7..26ec457eb4 100644
--- a/crates/precompile/src/bls12_381/utils.rs
+++ b/crates/precompile/src/bls12_381/utils.rs
@@ -19,31 +19,27 @@ pub(super) fn fp_to_bytes(out: &mut [u8], input: *const blst_fp) {
     if out.len() != PADDED_FP_LENGTH {
         return;
     }
-    for item in out.iter_mut().take(PADDING_LENGTH) {
-        *item = 0;
-    }
+    let (padding, rest) = out.split_at_mut(PADDING_LENGTH);
+    padding.fill(0);
     // SAFETY: out length is checked previously, input is a blst value.
-    unsafe {
-        blst_bendian_from_fp(out[PADDING_LENGTH..].as_mut_ptr(), input);
-    }
+    unsafe { blst_bendian_from_fp(rest.as_mut_ptr(), input) };
 }
 
 /// Removes zeros with which the precompile inputs are left padded to 64 bytes.
-pub(super) fn remove_padding(input: &[u8]) -> Result<[u8; FP_LENGTH], PrecompileError> {
+pub(super) fn remove_padding(input: &[u8]) -> Result<&[u8; FP_LENGTH], PrecompileError> {
     if input.len() != PADDED_FP_LENGTH {
         return Err(PrecompileError::Other(format!(
             "Padded Input should be {PADDED_FP_LENGTH} bits, was {}",
             input.len()
         )));
     }
-    if !input.iter().take(PADDING_LENGTH).all(|&x| x == 0) {
+    let (padding, unpadded) = input.split_at(PADDING_LENGTH);
+    if !padding.iter().all(|&x| x == 0) {
         return Err(PrecompileError::Other(format!(
             "{PADDING_LENGTH} top bytes of input are not zero",
         )));
     }
-
-    let sliced = &input[PADDING_LENGTH..PADDED_FP_LENGTH];
-    <[u8; FP_LENGTH]>::try_from(sliced).map_err(|e| PrecompileError::Other(format!("{e}")))
+    Ok(unpadded.try_into().unwrap())
 }
 
 /// Extracts an Scalar from a 32 byte slice representation.
@@ -57,9 +53,7 @@ pub(super) fn extract_scalar_input(input: &[u8]) -> Result<blst_scalar, Precompi
 
     let mut out = blst_scalar::default();
     // SAFETY: input length is checked previously, out is a blst value.
-    unsafe {
-        blst_scalar_from_bendian(&mut out, input.as_ptr());
-    }
+    unsafe { blst_scalar_from_bendian(&mut out, input.as_ptr()) };
 
     Ok(out)
 }

From 826cfced9d54ee8855a6c6e178a1c6604da5c22f Mon Sep 17 00:00:00 2001
From: DaniPopes <57450786+DaniPopes@users.noreply.github.com>
Date: Fri, 10 May 2024 11:05:31 +0200
Subject: [PATCH 2/2] chore: correct error message

---
 crates/precompile/src/bls12_381/g1.rs            | 2 +-
 crates/precompile/src/bls12_381/g1_add.rs        | 2 +-
 crates/precompile/src/bls12_381/g1_mul.rs        | 2 +-
 crates/precompile/src/bls12_381/g2.rs            | 2 +-
 crates/precompile/src/bls12_381/g2_add.rs        | 2 +-
 crates/precompile/src/bls12_381/g2_mul.rs        | 2 +-
 crates/precompile/src/bls12_381/map_fp2_to_g2.rs | 2 +-
 crates/precompile/src/bls12_381/map_fp_to_g1.rs  | 2 +-
 crates/precompile/src/bls12_381/utils.rs         | 4 ++--
 9 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/crates/precompile/src/bls12_381/g1.rs b/crates/precompile/src/bls12_381/g1.rs
index ca0b067047..163afb3e5b 100644
--- a/crates/precompile/src/bls12_381/g1.rs
+++ b/crates/precompile/src/bls12_381/g1.rs
@@ -22,7 +22,7 @@ pub(super) fn encode_g1_point(input: *const blst_p1_affine) -> Bytes {
 pub(super) fn extract_g1_input(input: &[u8]) -> Result<blst_p1_affine, PrecompileError> {
     if input.len() != G1_INPUT_ITEM_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "Input should be {G1_INPUT_ITEM_LENGTH} bits, was {}",
+            "Input should be {G1_INPUT_ITEM_LENGTH} bytes, was {}",
             input.len()
         )));
     }
diff --git a/crates/precompile/src/bls12_381/g1_add.rs b/crates/precompile/src/bls12_381/g1_add.rs
index ee3d308e81..358ab0cc0b 100644
--- a/crates/precompile/src/bls12_381/g1_add.rs
+++ b/crates/precompile/src/bls12_381/g1_add.rs
@@ -28,7 +28,7 @@ fn g1_add(input: &Bytes, gas_limit: u64) -> PrecompileResult {
 
     if input.len() != INPUT_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "G1ADD Input should be {INPUT_LENGTH} bits, was {}",
+            "G1ADD input should be {INPUT_LENGTH} bytes, was {}",
             input.len()
         )));
     }
diff --git a/crates/precompile/src/bls12_381/g1_mul.rs b/crates/precompile/src/bls12_381/g1_mul.rs
index d8d5e10bf3..8982cb5896 100644
--- a/crates/precompile/src/bls12_381/g1_mul.rs
+++ b/crates/precompile/src/bls12_381/g1_mul.rs
@@ -29,7 +29,7 @@ pub fn g1_mul(input: &Bytes, gas_limit: u64) -> PrecompileResult {
     }
     if input.len() != INPUT_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "G1MUL Input should be {INPUT_LENGTH} bits, was {}",
+            "G1MUL input should be {INPUT_LENGTH} bytes, was {}",
             input.len()
         )));
     }
diff --git a/crates/precompile/src/bls12_381/g2.rs b/crates/precompile/src/bls12_381/g2.rs
index 43386d90aa..538bc5beec 100644
--- a/crates/precompile/src/bls12_381/g2.rs
+++ b/crates/precompile/src/bls12_381/g2.rs
@@ -30,7 +30,7 @@ pub(super) fn encode_g2_point(input: &blst_p2_affine) -> Bytes {
 pub(super) fn extract_g2_input(input: &[u8]) -> Result<blst_p2_affine, PrecompileError> {
     if input.len() != G2_INPUT_ITEM_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "Input should be {G2_INPUT_ITEM_LENGTH} bits, was {}",
+            "Input should be {G2_INPUT_ITEM_LENGTH} bytes, was {}",
             input.len()
         )));
     }
diff --git a/crates/precompile/src/bls12_381/g2_add.rs b/crates/precompile/src/bls12_381/g2_add.rs
index 1a67597efb..28ca3f819f 100644
--- a/crates/precompile/src/bls12_381/g2_add.rs
+++ b/crates/precompile/src/bls12_381/g2_add.rs
@@ -29,7 +29,7 @@ fn g2_add(input: &Bytes, gas_limit: u64) -> PrecompileResult {
 
     if input.len() != INPUT_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "G2ADD Input should be {INPUT_LENGTH} bits, was {}",
+            "G2ADD input should be {INPUT_LENGTH} bytes, was {}",
             input.len()
         )));
     }
diff --git a/crates/precompile/src/bls12_381/g2_mul.rs b/crates/precompile/src/bls12_381/g2_mul.rs
index 0efd3595e7..d7d6883b23 100644
--- a/crates/precompile/src/bls12_381/g2_mul.rs
+++ b/crates/precompile/src/bls12_381/g2_mul.rs
@@ -29,7 +29,7 @@ fn g2_mul(input: &Bytes, gas_limit: u64) -> PrecompileResult {
     }
     if input.len() != INPUT_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "G2MUL Input should be {INPUT_LENGTH} bits, was {}",
+            "G2MUL input should be {INPUT_LENGTH} bytes, was {}",
             input.len()
         )));
     }
diff --git a/crates/precompile/src/bls12_381/map_fp2_to_g2.rs b/crates/precompile/src/bls12_381/map_fp2_to_g2.rs
index fffe73ba83..4615ffd862 100644
--- a/crates/precompile/src/bls12_381/map_fp2_to_g2.rs
+++ b/crates/precompile/src/bls12_381/map_fp2_to_g2.rs
@@ -28,7 +28,7 @@ fn map_fp2_to_g2(input: &Bytes, gas_limit: u64) -> PrecompileResult {
 
     if input.len() != PADDED_FP2_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "MAP_FP2_TO_G2 Input should be {PADDED_FP2_LENGTH} bits, was {}",
+            "MAP_FP2_TO_G2 input should be {PADDED_FP2_LENGTH} bytes, was {}",
             input.len()
         )));
     }
diff --git a/crates/precompile/src/bls12_381/map_fp_to_g1.rs b/crates/precompile/src/bls12_381/map_fp_to_g1.rs
index 795402a518..b161f7d397 100644
--- a/crates/precompile/src/bls12_381/map_fp_to_g1.rs
+++ b/crates/precompile/src/bls12_381/map_fp_to_g1.rs
@@ -26,7 +26,7 @@ fn map_fp_to_g1(input: &Bytes, gas_limit: u64) -> PrecompileResult {
 
     if input.len() != PADDED_FP_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "MAP_FP_TO_G1 Input should be {PADDED_FP_LENGTH} bits, was {}",
+            "MAP_FP_TO_G1 input should be {PADDED_FP_LENGTH} bytes, was {}",
             input.len()
         )));
     }
diff --git a/crates/precompile/src/bls12_381/utils.rs b/crates/precompile/src/bls12_381/utils.rs
index 26ec457eb4..3617a752c3 100644
--- a/crates/precompile/src/bls12_381/utils.rs
+++ b/crates/precompile/src/bls12_381/utils.rs
@@ -29,7 +29,7 @@ pub(super) fn fp_to_bytes(out: &mut [u8], input: *const blst_fp) {
 pub(super) fn remove_padding(input: &[u8]) -> Result<&[u8; FP_LENGTH], PrecompileError> {
     if input.len() != PADDED_FP_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "Padded Input should be {PADDED_FP_LENGTH} bits, was {}",
+            "Padded input should be {PADDED_FP_LENGTH} bytes, was {}",
             input.len()
         )));
     }
@@ -46,7 +46,7 @@ pub(super) fn remove_padding(input: &[u8]) -> Result<&[u8; FP_LENGTH], Precompil
 pub(super) fn extract_scalar_input(input: &[u8]) -> Result<blst_scalar, PrecompileError> {
     if input.len() != SCALAR_LENGTH {
         return Err(PrecompileError::Other(format!(
-            "Input should be {SCALAR_LENGTH} bits, was {}",
+            "Input should be {SCALAR_LENGTH} bytes, was {}",
             input.len()
         )));
     }