Add verifications in getHeader handler (#182)

* Add parent hash verification in getHeader Signed-off-by: Luca Georges Francois <[email protected]> * Remove unnecessary nil check Co-authored-by: Chris Hager <[email protected]> * Update error log in getHeader handler Signed-off-by: Luca Georges Francois <[email protected]> Co-authored-by: Chris Hager <[email protected]>
flashbots · Jul 4, 2022 · 3721723 · 3721723
1 parent 64edd7c
commit 3721723
Show file tree

Hide file tree

Showing 3 changed files with 22 additions and 1 deletion.
diff --git a/server/mock_relay.go b/server/mock_relay.go
@@ -144,7 +144,8 @@ func (m *mockRelay) MakeGetHeaderResponse(value uint64, hash, publicKey string)
 	// Fill the payload with custom values.
 	message := &types.BuilderBid{
 		Header: &types.ExecutionPayloadHeader{
-			BlockHash: _HexToHash(hash),
+			BlockHash:  _HexToHash(hash),
+			ParentHash: _HexToHash("0xe28385e7bd68df656cd0042b74b69c3104b5356ed1f20eb69f1f925df47a3ab7"),
 		},
 		Value:  types.IntToU256(value),
 		Pubkey: _HexToPubkey(publicKey),

diff --git a/server/service.go b/server/service.go
@@ -279,6 +279,16 @@ func (m *BoostService) handleGetHeader(w http.ResponseWriter, req *http.Request)
 				return
 			}
 
+			// Verify response coherence with proposer's input data
+			responseParentHash := responsePayload.Data.Message.Header.ParentHash.String()
+			if responseParentHash != parentHashHex {
+				log.WithFields(logrus.Fields{
+					"originalParentHash": parentHashHex,
+					"responseParentHash": responseParentHash,
+				}).Error("proposer and relay parent hashes are not the same")
+				return
+			}
+
 			// Compare value of header, skip processing this result if lower fee than current
 			mu.Lock()
 			defer mu.Unlock()

diff --git a/server/service_test.go b/server/service_test.go
@@ -366,6 +366,16 @@ func TestGetHeader(t *testing.T) {
 		require.Equal(t, http.StatusBadRequest, rr.Code, rr.Body.String())
 		require.Equal(t, 0, backend.relays[0].GetRequestCount(path))
 	})
+
+	t.Run("Invalid parent hash", func(t *testing.T) {
+		backend := newTestBackend(t, 1, time.Second)
+
+		invalidParentHashPath := getPath(1, types.Hash{}, pubkey)
+		rr := backend.request(t, http.MethodGet, invalidParentHashPath, nil)
+
+		require.Equal(t, `{"code":502,"message":"no successful relay response"}`+"\n", rr.Body.String())
+		require.Equal(t, 0, backend.relays[0].GetRequestCount(path))
+	})
 }
 
 func TestGetPayload(t *testing.T) {