chore: add eip4844 nonce gap error (#4414)

crates/rpc/rpc/src/eth/error.rs

@@ -520,6 +520,9 @@ impl From<InvalidPoolTransactionError> for RpcPoolError {
             InvalidPoolTransactionError::InvalidEip4844Blob(err) => {
                 RpcPoolError::InvalidEip4844Blob(err)
             }
+            InvalidPoolTransactionError::Eip4844NonceGap => {
+                RpcPoolError::Invalid(RpcInvalidTransactionError::NonceTooHigh)
+            }
         }
     }
 }

crates/transaction-pool/src/error.rs

@@ -144,6 +144,14 @@ pub enum InvalidPoolTransactionError {
     /// Thrown if validating the blob sidecar for the transaction failed.
     #[error(transparent)]
     InvalidEip4844Blob(BlobTransactionValidationError),
+    /// EIP-4844 transactions are only accepted if they're gapless, meaning the previous nonce of
+    /// the transaction (`tx.nonce -1`) must either be in the pool or match the on chain nonce of
+    /// the sender.
+    ///
+    /// This error is thrown on validation if a valid blob transaction arrives with a nonce that
+    /// would introduce gap in the nonce sequence.
+    #[error("Nonce too high.")]
+    Eip4844NonceGap,
     /// Any other error that occurred while inserting/validating that is transaction specific
     #[error("{0:?}")]
     Other(Box<dyn PoolTransactionError>),
@@ -210,6 +218,11 @@ impl InvalidPoolTransactionError {
                 // This is only reachable when the blob is invalid
                 true
             }
+            InvalidPoolTransactionError::Eip4844NonceGap => {
+                // it is possible that the pool sees `nonce n` before `nonce n-1` and this is only
+                // thrown for valid(good) blob transactions
+                false
+            }
         }
     }
 }

crates/transaction-pool/src/pool/txpool.rs

@@ -1085,7 +1085,7 @@ impl<T: PoolTransaction> AllTransactions<T> {
         false
     }
 
-    /// Inserts a new transaction into the pool.
+    /// Inserts a new _valid_ transaction into the pool.
     ///
     /// If the transaction already exists, it will be replaced if not underpriced.
     /// Returns info to which sub-pool the transaction should be moved.
@@ -1104,13 +1104,16 @@ impl<T: PoolTransaction> AllTransactions<T> {
         assert!(on_chain_nonce <= transaction.nonce(), "Invalid transaction");
 
         let transaction = Arc::new(self.ensure_valid(transaction)?);
-        let tx_id = *transaction.id();
+        let inserted_tx_id = *transaction.id();
         let mut state = TxState::default();
         let mut cumulative_cost = U256::ZERO;
         let mut updates = Vec::new();
 
-        let ancestor =
-            TransactionId::ancestor(transaction.transaction.nonce(), on_chain_nonce, tx_id.sender);
+        let ancestor = TransactionId::ancestor(
+            transaction.transaction.nonce(),
+            on_chain_nonce,
+            inserted_tx_id.sender,
+        );
 
         // If there's no ancestor tx then this is the next transaction.
         if ancestor.is_none() {
@@ -1133,6 +1136,7 @@ impl<T: PoolTransaction> AllTransactions<T> {
             state.insert(TxState::NOT_TOO_MUCH_GAS);
         }
 
+        // placeholder for the replaced transaction, if any
         let mut replaced_tx = None;
 
         let pool_tx = PoolInternalTransaction {
@@ -1175,6 +1179,7 @@ impl<T: PoolTransaction> AllTransactions<T> {
         // The next transaction of this sender
         let on_chain_id = TransactionId::new(transaction.sender_id(), on_chain_nonce);
         {
+            // get all transactions of the sender's account
             let mut descendants = self.descendant_txs_mut(&on_chain_id).peekable();
 
             // Tracks the next nonce we expect if the transactions are gapless
@@ -1189,7 +1194,7 @@ impl<T: PoolTransaction> AllTransactions<T> {
                 // SAFETY: the transaction was added above so the _inclusive_ descendants iterator
                 // returns at least 1 tx.
                 let (id, tx) = descendants.peek().expect("Includes >= 1; qed.");
-                if id.nonce < tx_id.nonce {
+                if id.nonce < inserted_tx_id.nonce {
                     !tx.state.is_pending()
                 } else {
                     true
@@ -1232,7 +1237,7 @@ impl<T: PoolTransaction> AllTransactions<T> {
                 // update the pool based on the state
                 tx.subpool = tx.state.into();
 
-                if tx_id.eq(id) {
+                if inserted_tx_id.eq(id) {
                     // if it is the new transaction, track the state
                     state = tx.state;
                 } else {
@@ -1254,7 +1259,7 @@ impl<T: PoolTransaction> AllTransactions<T> {
 
         // If this wasn't a replacement transaction we need to update the counter.
         if replaced_tx.is_none() {
-            self.tx_inc(tx_id.sender);
+            self.tx_inc(inserted_tx_id.sender);
         }
 
         Ok(InsertOk { transaction, move_to: state.into(), state, replaced_tx, updates })