fix: re-add validate_against_parent_4844 to optimism header validation (#8835)

Author: joshieDo

crates/consensus/common/src/validation.rs

@@ -6,6 +6,7 @@ use reth_primitives::{
         eip4844::{DATA_GAS_PER_BLOB, MAX_DATA_GAS_PER_BLOCK},
         MAXIMUM_EXTRA_DATA_SIZE,
     },
+    eip4844::calculate_excess_blob_gas,
     ChainSpec, GotExpected, Hardfork, Header, SealedBlock, SealedHeader,
 };
 
@@ -229,6 +230,41 @@ pub fn validate_against_parent_timestamp(
     Ok(())
 }
 
+/// Validates that the EIP-4844 header fields are correct with respect to the parent block. This
+/// ensures that the `blob_gas_used` and `excess_blob_gas` fields exist in the child header, and
+/// that the `excess_blob_gas` field matches the expected `excess_blob_gas` calculated from the
+/// parent header fields.
+pub fn validate_against_parent_4844(
+    header: &SealedHeader,
+    parent: &SealedHeader,
+) -> Result<(), ConsensusError> {
+    // From [EIP-4844](https://eips.ethereum.org/EIPS/eip-4844#header-extension):
+    //
+    // > For the first post-fork block, both parent.blob_gas_used and parent.excess_blob_gas
+    // > are evaluated as 0.
+    //
+    // This means in the first post-fork block, calculate_excess_blob_gas will return 0.
+    let parent_blob_gas_used = parent.blob_gas_used.unwrap_or(0);
+    let parent_excess_blob_gas = parent.excess_blob_gas.unwrap_or(0);
+
+    if header.blob_gas_used.is_none() {
+        return Err(ConsensusError::BlobGasUsedMissing)
+    }
+    let excess_blob_gas = header.excess_blob_gas.ok_or(ConsensusError::ExcessBlobGasMissing)?;
+
+    let expected_excess_blob_gas =
+        calculate_excess_blob_gas(parent_excess_blob_gas, parent_blob_gas_used);
+    if expected_excess_blob_gas != excess_blob_gas {
+        return Err(ConsensusError::ExcessBlobGasDiff {
+            diff: GotExpected { got: excess_blob_gas, expected: expected_excess_blob_gas },
+            parent_excess_blob_gas,
+            parent_blob_gas_used,
+        })
+    }
+
+    Ok(())
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

crates/ethereum/consensus/src/lib.rs

@@ -10,15 +10,14 @@
 
 use reth_consensus::{Consensus, ConsensusError, PostExecutionInput};
 use reth_consensus_common::validation::{
-    validate_4844_header_standalone, validate_against_parent_eip1559_base_fee,
-    validate_against_parent_hash_number, validate_against_parent_timestamp,
-    validate_block_pre_execution, validate_header_base_fee, validate_header_extradata,
-    validate_header_gas,
+    validate_4844_header_standalone, validate_against_parent_4844,
+    validate_against_parent_eip1559_base_fee, validate_against_parent_hash_number,
+    validate_against_parent_timestamp, validate_block_pre_execution, validate_header_base_fee,
+    validate_header_extradata, validate_header_gas,
 };
 use reth_primitives::{
-    constants::MINIMUM_GAS_LIMIT, eip4844::calculate_excess_blob_gas, BlockWithSenders, Chain,
-    ChainSpec, GotExpected, Hardfork, Header, SealedBlock, SealedHeader, EMPTY_OMMER_ROOT_HASH,
-    U256,
+    constants::MINIMUM_GAS_LIMIT, BlockWithSenders, Chain, ChainSpec, Hardfork, Header,
+    SealedBlock, SealedHeader, EMPTY_OMMER_ROOT_HASH, U256,
 };
 use std::{sync::Arc, time::SystemTime};
 
@@ -40,41 +39,6 @@ impl EthBeaconConsensus {
         Self { chain_spec }
     }
 
-    /// Validates that the EIP-4844 header fields are correct with respect to the parent block. This
-    /// ensures that the `blob_gas_used` and `excess_blob_gas` fields exist in the child header, and
-    /// that the `excess_blob_gas` field matches the expected `excess_blob_gas` calculated from the
-    /// parent header fields.
-    pub fn validate_against_parent_4844(
-        header: &SealedHeader,
-        parent: &SealedHeader,
-    ) -> Result<(), ConsensusError> {
-        // From [EIP-4844](https://eips.ethereum.org/EIPS/eip-4844#header-extension):
-        //
-        // > For the first post-fork block, both parent.blob_gas_used and parent.excess_blob_gas
-        // > are evaluated as 0.
-        //
-        // This means in the first post-fork block, calculate_excess_blob_gas will return 0.
-        let parent_blob_gas_used = parent.blob_gas_used.unwrap_or(0);
-        let parent_excess_blob_gas = parent.excess_blob_gas.unwrap_or(0);
-
-        if header.blob_gas_used.is_none() {
-            return Err(ConsensusError::BlobGasUsedMissing)
-        }
-        let excess_blob_gas = header.excess_blob_gas.ok_or(ConsensusError::ExcessBlobGasMissing)?;
-
-        let expected_excess_blob_gas =
-            calculate_excess_blob_gas(parent_excess_blob_gas, parent_blob_gas_used);
-        if expected_excess_blob_gas != excess_blob_gas {
-            return Err(ConsensusError::ExcessBlobGasDiff {
-                diff: GotExpected { got: excess_blob_gas, expected: expected_excess_blob_gas },
-                parent_excess_blob_gas,
-                parent_blob_gas_used,
-            })
-        }
-
-        Ok(())
-    }
-
     /// Checks the gas limit for consistency between parent and self headers.
     ///
     /// The maximum allowable difference between self and parent gas limits is determined by the
@@ -175,7 +139,7 @@ impl Consensus for EthBeaconConsensus {
 
         // ensure that the blob gas fields for this block
         if self.chain_spec.is_cancun_active_at_timestamp(header.timestamp) {
-            Self::validate_against_parent_4844(header, parent)?;
+            validate_against_parent_4844(header, parent)?;
         }
 
         Ok(())

crates/optimism/consensus/src/lib.rs

@@ -11,9 +11,10 @@
 
 use reth_consensus::{Consensus, ConsensusError, PostExecutionInput};
 use reth_consensus_common::validation::{
-    validate_against_parent_eip1559_base_fee, validate_against_parent_hash_number,
-    validate_against_parent_timestamp, validate_block_pre_execution, validate_header_base_fee,
-    validate_header_extradata, validate_header_gas,
+    validate_against_parent_4844, validate_against_parent_eip1559_base_fee,
+    validate_against_parent_hash_number, validate_against_parent_timestamp,
+    validate_block_pre_execution, validate_header_base_fee, validate_header_extradata,
+    validate_header_gas,
 };
 use reth_primitives::{
     BlockWithSenders, ChainSpec, Header, SealedBlock, SealedHeader, EMPTY_OMMER_ROOT_HASH, U256,
@@ -63,6 +64,11 @@ impl Consensus for OptimismBeaconConsensus {
 
         validate_against_parent_eip1559_base_fee(header, parent, &self.chain_spec)?;
 
+        // ensure that the blob gas fields for this block
+        if self.chain_spec.is_cancun_active_at_timestamp(header.timestamp) {
+            validate_against_parent_4844(header, parent)?;
+        }
+
         Ok(())
     }