diff --git a/protocol/detect.go b/protocol/detect.go
index b05179b..de9fd2e 100644
--- a/protocol/detect.go
+++ b/protocol/detect.go
@@ -45,7 +45,7 @@ func (dir Direction) Contains(other Direction) bool {
 	case Server:
 		return other == Server || other == Both
 	case Both:
-		return other == Client || other == Server
+		return other == Client || other == Server || other == Both
 	default:
 		return false
 	}