http2: support custom SETTINGS parameters (#9964)

Signed-off-by: Andres Guedez <aguedez@google.com>

Mirrored from https://github.com/envoyproxy/envoy @ 56e5b84f4730d124d5080bbb72f88b70d02b99eb

envoy/api/v2/core/protocol.proto

@@ -112,8 +112,21 @@ message Http1ProtocolOptions {
   bool enable_trailers = 5;
 }
 
-// [#next-free-field: 13]
+// [#next-free-field: 14]
 message Http2ProtocolOptions {
+  // Defines a parameter to be sent in the SETTINGS frame.
+  // See `RFC7540, sec. 6.5.1 <https://tools.ietf.org/html/rfc7540#section-6.5.1>`_ for details.
+  message SettingsParameter {
+    // The 16 bit parameter identifier.
+    google.protobuf.UInt32Value identifier = 1 [
+      (validate.rules).uint32 = {lte: 65536 gte: 1},
+      (validate.rules).message = {required: true}
+    ];
+
+    // The 32 bit parameter value.
+    google.protobuf.UInt32Value value = 2 [(validate.rules).message = {required: true}];
+  }
+
   // `Maximum table size <https://httpwg.org/specs/rfc7541.html#rfc.section.4.2>`_
   // (in octets) that the encoder is permitted to use for the dynamic HPACK table. Valid values
   // range from 0 to 4294967295 (2^32 - 1) and defaults to 4096. 0 effectively disables header
@@ -216,6 +229,34 @@ message Http2ProtocolOptions {
   //
   // See `RFC7540, sec. 8.1 <https://tools.ietf.org/html/rfc7540#section-8.1>`_ for details.
   bool stream_error_on_invalid_http_messaging = 12;
+
+  // [#not-implemented-hide:]
+  // Specifies SETTINGS frame parameters to be sent to the peer, with two exceptions:
+  //
+  // 1. SETTINGS_ENABLE_PUSH (0x2) is not configurable as HTTP/2 server push is not supported by
+  // Envoy.
+  //
+  // 2. SETTINGS_ENABLE_CONNECT_PROTOCOL (0x8) is only configurable through the named field
+  // 'allow_connect'.
+  //
+  // Note that custom parameters specified through this field can not also be set in the
+  // corresponding named parameters:
+  //
+  // .. code-block:: text
+  //
+  //   ID    Field Name
+  //   ----------------
+  //   0x1   hpack_table_size
+  //   0x3   max_concurrent_streams
+  //   0x4   initial_stream_window_size
+  //
+  // Collisions will trigger config validation failure on load/update. Likewise, inconsistencies
+  // between custom parameters with the same identifier will trigger a failure.
+  //
+  // See `IANA HTTP/2 Settings
+  // <https://www.iana.org/assignments/http2-parameters/http2-parameters.xhtml#settings>`_ for
+  // standardized identifiers.
+  repeated SettingsParameter custom_settings_parameters = 13;
 }
 
 // [#not-implemented-hide:]

envoy/config/core/v3/protocol.proto

@@ -128,11 +128,27 @@ message Http1ProtocolOptions {
   bool enable_trailers = 5;
 }
 
-// [#next-free-field: 13]
+// [#next-free-field: 14]
 message Http2ProtocolOptions {
   option (udpa.annotations.versioning).previous_message_type =
       "envoy.api.v2.core.Http2ProtocolOptions";
 
+  // Defines a parameter to be sent in the SETTINGS frame.
+  // See `RFC7540, sec. 6.5.1 <https://tools.ietf.org/html/rfc7540#section-6.5.1>`_ for details.
+  message SettingsParameter {
+    option (udpa.annotations.versioning).previous_message_type =
+        "envoy.api.v2.core.Http2ProtocolOptions.SettingsParameter";
+
+    // The 16 bit parameter identifier.
+    google.protobuf.UInt32Value identifier = 1 [
+      (validate.rules).uint32 = {lte: 65536 gte: 1},
+      (validate.rules).message = {required: true}
+    ];
+
+    // The 32 bit parameter value.
+    google.protobuf.UInt32Value value = 2 [(validate.rules).message = {required: true}];
+  }
+
   // `Maximum table size <https://httpwg.org/specs/rfc7541.html#rfc.section.4.2>`_
   // (in octets) that the encoder is permitted to use for the dynamic HPACK table. Valid values
   // range from 0 to 4294967295 (2^32 - 1) and defaults to 4096. 0 effectively disables header
@@ -235,6 +251,34 @@ message Http2ProtocolOptions {
   //
   // See `RFC7540, sec. 8.1 <https://tools.ietf.org/html/rfc7540#section-8.1>`_ for details.
   bool stream_error_on_invalid_http_messaging = 12;
+
+  // [#not-implemented-hide:]
+  // Specifies SETTINGS frame parameters to be sent to the peer, with two exceptions:
+  //
+  // 1. SETTINGS_ENABLE_PUSH (0x2) is not configurable as HTTP/2 server push is not supported by
+  // Envoy.
+  //
+  // 2. SETTINGS_ENABLE_CONNECT_PROTOCOL (0x8) is only configurable through the named field
+  // 'allow_connect'.
+  //
+  // Note that custom parameters specified through this field can not also be set in the
+  // corresponding named parameters:
+  //
+  // .. code-block:: text
+  //
+  //   ID    Field Name
+  //   ----------------
+  //   0x1   hpack_table_size
+  //   0x3   max_concurrent_streams
+  //   0x4   initial_stream_window_size
+  //
+  // Collisions will trigger config validation failure on load/update. Likewise, inconsistencies
+  // between custom parameters with the same identifier will trigger a failure.
+  //
+  // See `IANA HTTP/2 Settings
+  // <https://www.iana.org/assignments/http2-parameters/http2-parameters.xhtml#settings>`_ for
+  // standardized identifiers.
+  repeated SettingsParameter custom_settings_parameters = 13;
 }
 
 // [#not-implemented-hide:]