feat: punish malicious peers (#16818)

Co-authored-by: Matthias Seitz <[email protected]>

Author: varun-doshi

crates/net/network/src/transactions/fetcher.rs

@@ -882,15 +882,19 @@ impl<N: NetworkPrimitives> TransactionFetcher<N> {
                 if unsolicited > 0 {
                     self.metrics.unsolicited_transactions.increment(unsolicited as u64);
                 }
-                if verification_outcome == VerificationOutcome::ReportPeer {
-                    // todo: report peer for sending hashes that weren't requested
+
+                let report_peer = if verification_outcome == VerificationOutcome::ReportPeer {
                     trace!(target: "net::tx",
                         peer_id=format!("{peer_id:#}"),
                         unverified_len,
                         verified_payload_len=verified_payload.len(),
                         "received `PooledTransactions` response from peer with entries that didn't verify against request, filtered out transactions"
                     );
-                }
+                    true
+                } else {
+                    false
+                };
+
                 // peer has only sent hashes that we didn't request
                 if verified_payload.is_empty() {
                     return FetchEvent::FetchError { peer_id, error: RequestError::BadResponse }
@@ -952,7 +956,7 @@ impl<N: NetworkPrimitives> TransactionFetcher<N> {
 
                 let transactions = valid_payload.into_data().into_values().collect();
 
-                FetchEvent::TransactionsFetched { peer_id, transactions }
+                FetchEvent::TransactionsFetched { peer_id, transactions, report_peer }
             }
             Ok(Err(req_err)) => {
                 self.try_buffer_hashes_for_retry(requested_hashes, &peer_id);
@@ -1039,6 +1043,9 @@ pub enum FetchEvent<T = PooledTransaction> {
         peer_id: PeerId,
         /// The transactions that were fetched, if available.
         transactions: PooledTransactions<T>,
+        /// Whether the peer should be penalized for sending unsolicited transactions or for
+        /// misbehavior.
+        report_peer: bool,
     },
     /// Triggered when there is an error in fetching transactions.
     FetchError {

crates/net/network/src/transactions/mod.rs

@@ -1456,8 +1456,11 @@ where
     /// Processes a [`FetchEvent`].
     fn on_fetch_event(&mut self, fetch_event: FetchEvent<N::PooledTransaction>) {
         match fetch_event {
-            FetchEvent::TransactionsFetched { peer_id, transactions } => {
+            FetchEvent::TransactionsFetched { peer_id, transactions, report_peer } => {
                 self.import_transactions(peer_id, transactions, TransactionSource::Response);
+                if report_peer {
+                    self.report_peer(peer_id, ReputationChangeKind::BadTransactions);
+                }
             }
             FetchEvent::FetchError { peer_id, error } => {
                 trace!(target: "net::tx", ?peer_id, %error, "requesting transactions from peer failed");