Add TcpClusterRewrite config proto

envoy/config/filter/network/tcp_cluster_rewrite/v2alpha1/config.proto

@@ -0,0 +1,29 @@
+// Copyright 2018 Istio Authors
+//
+//   Licensed under the Apache License, Version 2.0 (the "License");
+//   you may not use this file except in compliance with the License.
+//   You may obtain a copy of the License at
+//
+//       http://www.apache.org/licenses/LICENSE-2.0
+//
+//   Unless required by applicable law or agreed to in writing, software
+//   distributed under the License is distributed on an "AS IS" BASIS,
+//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//   See the License for the specific language governing permissions and
+//   limitations under the License.
+
+syntax = "proto3";
+
+// $title: TCP cluster rewrite filter configuration for Envoy.
+
+package istio.envoy.config.filter.network.tcp_cluster_rewrite.v2alpha1;
+
+option go_package = "istio.io/api/envoy/config/filter/network/tcp_cluster_rewrite/v2alpha1";
+
+// TcpClusterRewrite is the config for the TCP cluster rewrite filter.
+message TcpClusterRewrite {
+  // Specifies the regex pattern to be matched in the cluster name.
+  string cluster_pattern = 1;
+  // Specifies the replacement for the matched cluster pattern.
+  string cluster_replacement = 2;
+}