api: add auto_sni flag on CDS API (#8889)

Description: add auto_sni flag on cluster that executes to change sni field on sni field automatically.
Risk Level: Low
Testing: Unit Test
Docs Changes: Added
Release Notes: Added

Signed-off-by: shikugawa <rei@tetrate.io>

Mirrored from https://github.com/envoyproxy/envoy @ 18ec59136e7a265556ca1d660dd7eb103182ea3a

envoy/api/v2/cluster.proto

@@ -30,7 +30,7 @@ option (udpa.annotations.file_migrate).move_to_package = "envoy.config.cluster.v
 // [#protodoc-title: Cluster configuration]
 
 // Configuration for a single upstream cluster.
-// [#next-free-field: 46]
+// [#next-free-field: 47]
 message Cluster {
   // Refer to :ref:`service discovery type <arch_overview_service_discovery_types>`
   // for an explanation on each type.
@@ -592,6 +592,10 @@ message Cluster {
   //   set, `transport_socket` takes priority.
   auth.UpstreamTlsContext tls_context = 11 [deprecated = true];
 
+  // HTTP protocol options that are applied only to upstream HTTP connections.
+  // These options apply to all HTTP versions.
+  core.UpstreamHttpProtocolOptions upstream_http_protocol_options = 46;
+
   // Additional options when handling HTTP requests upstream. These options will be applicable to
   // both HTTP1 and HTTP2 requests.
   core.HttpProtocolOptions common_http_protocol_options = 29;

envoy/api/v2/core/protocol.proto

@@ -19,6 +19,13 @@ option (udpa.annotations.file_migrate).move_to_package = "envoy.config.core.v3al
 message TcpProtocolOptions {
 }
 
+message UpstreamHttpProtocolOptions {
+  // Set transport socket `SNI <https://en.wikipedia.org/wiki/Server_Name_Indication>`_ for new
+  // upstream connections based on the downstream HTTP host/authority header, as seen by the
+  // :ref:`router filter <config_http_filters_router>`.
+  bool auto_sni = 1;
+}
+
 message HttpProtocolOptions {
   // The idle timeout for connections. The idle timeout is defined as the
   // period in which there are no active requests. If not set, there is no idle timeout. When the

envoy/config/cluster/v3alpha/cluster.proto

@@ -29,7 +29,7 @@ option java_multiple_files = true;
 // [#protodoc-title: Cluster configuration]
 
 // Configuration for a single upstream cluster.
-// [#next-free-field: 46]
+// [#next-free-field: 47]
 message Cluster {
   option (udpa.annotations.versioning).previous_message_type = "envoy.api.v2.Cluster";
 
@@ -627,6 +627,10 @@ message Cluster {
   // Optional :ref:`circuit breaking <arch_overview_circuit_break>` for the cluster.
   CircuitBreakers circuit_breakers = 10;
 
+  // HTTP protocol options that are applied only to upstream HTTP connections.
+  // These options apply to all HTTP versions.
+  core.v3alpha.UpstreamHttpProtocolOptions upstream_http_protocol_options = 46;
+
   // Additional options when handling HTTP requests upstream. These options will be applicable to
   // both HTTP1 and HTTP2 requests.
   core.v3alpha.HttpProtocolOptions common_http_protocol_options = 29;

envoy/config/core/v3alpha/protocol.proto

@@ -21,6 +21,16 @@ message TcpProtocolOptions {
       "envoy.api.v2.core.TcpProtocolOptions";
 }
 
+message UpstreamHttpProtocolOptions {
+  option (udpa.annotations.versioning).previous_message_type =
+      "envoy.api.v2.core.UpstreamHttpProtocolOptions";
+
+  // Set transport socket `SNI <https://en.wikipedia.org/wiki/Server_Name_Indication>`_ for new
+  // upstream connections based on the downstream HTTP host/authority header, as seen by the
+  // :ref:`router filter <config_http_filters_router>`.
+  bool auto_sni = 1;
+}
+
 message HttpProtocolOptions {
   option (udpa.annotations.versioning).previous_message_type =
       "envoy.api.v2.core.HttpProtocolOptions";