fix: limit size to max pairing input size given 20M gas

Author: refcell

Cargo.lock

@@ -19,6 +19,9 @@ use revm::{
     primitives::PrecompileOutput,
 };
 
+/// The max pairing size for BLS12-381 input given a 20M gas limit.
+const BLS12_MAX_PAIRING_SIZE_ISTHMUS: usize = 235_008;
+
 /// The address of the BLS12-381 pairing check precompile.
 const BLS12_PAIRING_CHECK: Address = address!("0x000000000000000000000000000000000000000f");
 
@@ -32,8 +35,8 @@ const PAIRING_MULTIPLIER_BASE: u64 = 32600;
 const PAIRING_OFFSET_BASE: u64 = 37700;
 
 /// The address of the BLS12-381 pairing precompile.
-pub(crate) const FPVM_BLS12_PAIRING: PrecompileWithAddress =
-    PrecompileWithAddress(BLS12_PAIRING_CHECK, Precompile::Standard(fpvm_bls12_pairing));
+pub(crate) const FPVM_BLS12_PAIRING_ISTHMUS: PrecompileWithAddress =
+    PrecompileWithAddress(BLS12_PAIRING_CHECK, Precompile::Standard(fpvm_bls12_pairing_isthmus));
 
 /// Performs an FPVM-accelerated BLS12-381 pairing check.
 fn fpvm_bls12_pairing(input: &Bytes, gas_limit: u64) -> PrecompileResult {
@@ -91,11 +94,33 @@ fn fpvm_bls12_pairing(input: &Bytes, gas_limit: u64) -> PrecompileResult {
     Ok(PrecompileOutput::new(required_gas, result_data.into()))
 }
 
+/// Performs an FPVM-accelerated `bls12` pairing check precompile call
+/// after the Isthmus Hardfork.
+fn fpvm_bls12_pairing_isthmus(input: &Bytes, gas_limit: u64) -> PrecompileResult {
+    if input.len() > BLS12_MAX_PAIRING_SIZE_ISTHMUS {
+        return Err(PrecompileError::Other(alloc::format!(
+            "Pairing input length must be at most {}",
+            BLS12_MAX_PAIRING_SIZE_ISTHMUS
+        ))
+        .into());
+    }
+
+    fpvm_bls12_pairing(input, gas_limit)
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
     use alloc::vec;
 
+    #[test]
+    fn test_fpvm_bls12_pairing_isthmus_max_bytes() {
+        let input = Bytes::from(vec![0u8; BLS12_MAX_PAIRING_SIZE_ISTHMUS + 1]);
+        let gas_limit = PAIRING_MULTIPLIER_BASE;
+        let err = PrecompileError::Other("Pairing input length must be at most 235008".to_string());
+        assert_eq!(fpvm_bls12_pairing_isthmus(&input, gas_limit), Err(err.into()));
+    }
+
     #[test]
     fn test_fpvm_bls12_offset() {
         let input = Bytes::from(vec![0u8; INPUT_LENGTH + 1]);

bin/client/src/precompiles/bls12.rs

@@ -34,7 +34,6 @@ pub(crate) fn fpvm_handle_register<F, H>(
 
         // Extend with FPVM-accelerated precompiles
         let override_precompiles = [
-            bls12::FPVM_BLS12_PAIRING,
             ecrecover::FPVM_ECRECOVER,
             bn128_pair::FPVM_ECPAIRING,
             kzg_point_eval::FPVM_KZG_POINT_EVAL,
@@ -45,6 +44,10 @@ pub(crate) fn fpvm_handle_register<F, H>(
             ctx_precompiles.extend([bn128_pair::FPVM_ECPAIRING_GRANITE]);
         }
 
+        if spec_id.is_enabled_in(SpecId::ISTANBUL) {
+            ctx_precompiles.extend([bls12::FPVM_BLS12_PAIRING_ISTHMUS]);
+        }
+
         ctx_precompiles
     });
 }