lua: Expose stream info downstreamLocalAddress and downstreamDirectRemoteAddress for Lua filter

docs/root/configuration/http/http_filters/lua_filter.rst

@@ -643,6 +643,26 @@ protocol()
 Returns the string representation of :repo:`HTTP protocol <include/envoy/http/protocol.h>`
 used by the current request. The possible values are: *HTTP/1.0*, *HTTP/1.1*, and *HTTP/2*.
 
+downstreamLocalAddress()
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. code-block:: lua
+
+  streamInfo:downstreamLocalAddress()
+
+Returns the string representation of :repo:`downstream remote address <include/envoy/stream_info/stream_info.h>`
+used by the current request.
+
+downstreamDirectRemoteAddress()
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. code-block:: lua
+
+  streamInfo:downstreamDirectRemoteAddress()
+
+Returns the string representation of :repo:`downstream directly connected address <include/envoy/stream_info/stream_info.h>`
+used by the current request. This is equivalent to the address of the physical connection.
+
 dynamicMetadata()
 ^^^^^^^^^^^^^^^^^
 

docs/root/version_history/current.rst

@@ -34,6 +34,7 @@ New Features
 * hds: added support for delta updates in the :ref:`HealthCheckSpecifier <envoy_v3_api_msg_service.health.v3.HealthCheckSpecifier>`, making only the Endpoints and Health Checkers that changed be reconstructed on receiving a new message, rather than the entire HDS.
 * health_check: added option to use :ref:`no_traffic_healthy_interval <envoy_v3_api_field_config.core.v3.HealthCheck.no_traffic_healthy_interval>` which allows a different no traffic interval when the host is healthy.
 * listener: added an optional :ref:`default filter chain <envoy_v3_api_field_config.listener.v3.Listener.default_filter_chain>`. If this field is supplied, and none of the :ref:`filter_chains <envoy_v3_api_field_config.listener.v3.Listener.filter_chains>` matches, this default filter chain is used to serve the connection.
+* lua: added `downstreamDirectRemoteAddress()` and `downstreamLocalAddress()` APIs to :ref:`streamInfo() <config_http_filters_lua_stream_info_wrapper>`.
 * mongo_proxy: the list of commands to produce metrics for is now :ref:`configurable <envoy_v3_api_field_extensions.filters.network.mongo_proxy.v3.MongoProxy.commands>`.
 * ratelimit: added support for use of various :ref:`metadata <envoy_v3_api_field_config.route.v3.RateLimit.Action.metadata>` as a ratelimit action.
 * ratelimit: added :ref:`disable_x_envoy_ratelimited_header <envoy_v3_api_msg_extensions.filters.http.ratelimit.v3.RateLimit>` option to disable `X-Envoy-RateLimited` header.

source/extensions/filters/http/lua/wrappers.cc

@@ -129,6 +129,16 @@ int StreamInfoWrapper::luaDownstreamSslConnection(lua_State* state) {
   return 1;
 }
 
+int StreamInfoWrapper::luaDownstreamLocalAddress(lua_State* state) {
+  lua_pushstring(state, stream_info_.downstreamLocalAddress()->asString().c_str());
+  return 1;
+}
+
+int StreamInfoWrapper::luaDownstreamDirectRemoteAddress(lua_State* state) {
+  lua_pushstring(state, stream_info_.downstreamDirectRemoteAddress()->asString().c_str());
+  return 1;
+}
+
 DynamicMetadataMapIterator::DynamicMetadataMapIterator(DynamicMetadataMapWrapper& parent)
     : parent_{parent}, current_{parent_.streamInfo().dynamicMetadata().filter_metadata().begin()} {}
 

source/extensions/filters/http/lua/wrappers.h

@@ -184,6 +184,8 @@ class StreamInfoWrapper : public Filters::Common::Lua::BaseLuaObject<StreamInfoW
   static ExportedFunctions exportedFunctions() {
     return {{"protocol", static_luaProtocol},
             {"dynamicMetadata", static_luaDynamicMetadata},
+            {"downstreamLocalAddress", static_luaDownstreamLocalAddress},
+            {"downstreamDirectRemoteAddress", static_luaDownstreamDirectRemoteAddress},
             {"downstreamSslConnection", static_luaDownstreamSslConnection}};
   }
 
@@ -206,6 +208,19 @@ class StreamInfoWrapper : public Filters::Common::Lua::BaseLuaObject<StreamInfoW
    */
   DECLARE_LUA_FUNCTION(StreamInfoWrapper, luaDownstreamSslConnection);
 
+  /**
+   * Get current downstream local address
+   * @return string representation of downstream local address.
+   */
+  DECLARE_LUA_FUNCTION(StreamInfoWrapper, luaDownstreamLocalAddress);
+
+  /**
+   * Get current downstream local address
+   * @return string representation of downstream directly connected address.
+   * This is equivalent to the address of the physical connection.
+   */
+  DECLARE_LUA_FUNCTION(StreamInfoWrapper, luaDownstreamDirectRemoteAddress);
+
   // Envoy::Lua::BaseLuaObject
   void onMarkDead() override { dynamic_metadata_wrapper_.reset(); }
 

test/extensions/filters/http/lua/BUILD

@@ -38,6 +38,7 @@ envoy_extension_cc_test(
     srcs = ["wrappers_test.cc"],
     extension_name = "envoy.filters.http.lua",
     deps = [
+        "//source/common/network:address_lib",
         "//source/common/stream_info:stream_info_lib",
         "//source/extensions/filters/http/lua:wrappers_lib",
         "//test/extensions/filters/common/lua:lua_wrappers_lib",

test/extensions/filters/http/lua/lua_integration_test.cc

@@ -266,6 +266,10 @@ name: lua
       end
       request_handle:headers():add("request_protocol", request_handle:streamInfo():protocol())
       request_handle:headers():add("request_dynamic_metadata_value", dynamic_metadata_value)
+      request_handle:headers():add("request_downstream_local_address_value", 
+        request_handle:streamInfo():downstreamLocalAddress())
+      request_handle:headers():add("request_downstream_directremote_address_value", 
+        request_handle:streamInfo():downstreamDirectRemoteAddress())
     end
 
     function envoy_on_response(response_handle)
@@ -325,6 +329,20 @@ name: lua
                        ->value()
                        .getStringView());
 
+  EXPECT_TRUE(
+      absl::StrContains(upstream_request_->headers()
+                            .get(Http::LowerCaseString("request_downstream_local_address_value"))[0]
+                            ->value()
+                            .getStringView(),
+                        GetParam() == Network::Address::IpVersion::v4 ? "127.0.0.1:" : "[::1]:"));
+
+  EXPECT_TRUE(absl::StrContains(
+      upstream_request_->headers()
+          .get(Http::LowerCaseString("request_downstream_directremote_address_value"))[0]
+          ->value()
+          .getStringView(),
+      GetParam() == Network::Address::IpVersion::v4 ? "127.0.0.1:" : "[::1]:"));
+
   Http::TestResponseHeaderMapImpl response_headers{{":status", "200"}, {"foo", "bar"}};
   upstream_request_->encodeHeaders(response_headers, false);
   Buffer::OwnedImpl response_data1("good");

test/extensions/filters/http/lua/wrappers_test.cc

@@ -1,6 +1,7 @@
 #include "envoy/config/core/v3/base.pb.h"
 
 #include "common/http/utility.h"
+#include "common/network/address_impl.h"
 #include "common/stream_info/stream_info_impl.h"
 
 #include "extensions/filters/http/lua/wrappers.h"
@@ -11,6 +12,7 @@
 
 using testing::InSequence;
 using testing::ReturnPointee;
+using testing::ReturnRef;
 
 namespace Envoy {
 namespace Extensions {
@@ -269,6 +271,35 @@ TEST_F(LuaStreamInfoWrapperTest, ReturnCurrentProtocol) {
   expectToPrintCurrentProtocol(Http::Protocol::Http2);
 }
 
+// Verify downstream local addresses and downstream direct remote addresses are available from
+// stream info wrapper.
+TEST_F(LuaStreamInfoWrapperTest, ReturnCurrentDownstreamAddresses) {
+  const std::string SCRIPT{R"EOF(
+      function callMe(object)
+        testPrint(object:downstreamLocalAddress())
+        testPrint(object:downstreamDirectRemoteAddress())
+      end
+    )EOF"};
+
+  InSequence s;
+  setup(SCRIPT);
+
+  NiceMock<Envoy::StreamInfo::MockStreamInfo> stream_info;
+  auto address = Network::Address::InstanceConstSharedPtr{
+      new Network::Address::Ipv4Instance("127.0.0.1", 8000)};
+  auto downstream_direct_remote =
+      Network::Address::InstanceConstSharedPtr{new Network::Address::Ipv4Instance("8.8.8.8", 3000)};
+  ON_CALL(stream_info, downstreamLocalAddress()).WillByDefault(ReturnRef(address));
+  ON_CALL(stream_info, downstreamDirectRemoteAddress())
+      .WillByDefault(ReturnRef(downstream_direct_remote));
+  Filters::Common::Lua::LuaDeathRef<StreamInfoWrapper> wrapper(
+      StreamInfoWrapper::create(coroutine_->luaState(), stream_info), true);
+  EXPECT_CALL(printer_, testPrint(address->asString()));
+  EXPECT_CALL(printer_, testPrint(downstream_direct_remote->asString()));
+  start("callMe");
+  wrapper.reset();
+}
+
 // Set, get and iterate stream info dynamic metadata.
 TEST_F(LuaStreamInfoWrapperTest, SetGetAndIterateDynamicMetadata) {
   const std::string SCRIPT{R"EOF(