test: creating a test listener filter and moving the xds test over to it (envoyproxy#20571)

Part of envoyproxy#9953

Signed-off-by: Alyssa Wilk <alyssar@chromium.org>

Author: alyssawilk

test/config/utility.cc

@@ -145,6 +145,14 @@ std::string ConfigHelper::startTlsConfig() {
                   TestEnvironment::runfilesPath("test/config/integration/certs/serverkey.pem")));
 }
 
+std::string ConfigHelper::testInspectorFilter() {
+  return R"EOF(
+name: "envoy.filters.listener.test"
+typed_config:
+  "@type": type.googleapis.com/google.protobuf.Struct
+)EOF";
+}
+
 std::string ConfigHelper::tlsInspectorFilter(bool enable_ja3_fingerprinting) {
   if (!enable_ja3_fingerprinting) {
     return R"EOF(

test/config/utility.h

@@ -147,6 +147,9 @@ class ConfigHelper {
   // A string for a tls inspector listener filter which can be used with addListenerFilter()
   static std::string tlsInspectorFilter(bool enable_ja3_fingerprinting = false);
 
+  // A string for the test inspector filter.
+  static std::string testInspectorFilter();
+
   // A basic configuration for L4 proxying.
   static std::string tcpProxyConfig();
   // A basic configuration for L7 proxying.

test/integration/BUILD

@@ -1433,11 +1433,11 @@ envoy_cc_test(
         ":http_integration_lib",
         ":http_protocol_integration_lib",
         "//source/extensions/filters/listener/tls_inspector:config",
-        "//source/extensions/filters/listener/tls_inspector:tls_inspector_lib",
         "//source/extensions/filters/network/tcp_proxy:config",
         "//source/extensions/transport_sockets/tls:config",
         "//source/extensions/transport_sockets/tls:context_config_lib",
         "//source/extensions/transport_sockets/tls:context_lib",
+        "//test/integration/filters:test_listener_filter_lib",
         "//test/test_common:environment_lib",
         "//test/test_common:utility_lib",
         "@envoy_api//envoy/config/bootstrap/v3:pkg_cc_proto",

test/integration/filters/BUILD

@@ -14,6 +14,21 @@ envoy_proto_library(
     srcs = ["add_body_filter.proto"],
 )
 
+envoy_cc_test_library(
+    name = "test_listener_filter_lib",
+    srcs = [
+        "test_listener_filter.cc",
+    ],
+    hdrs = [
+        "test_listener_filter.h",
+    ],
+    deps = [
+        "//envoy/network:filter_interface",
+        "//envoy/registry",
+        "//envoy/server:filter_config_interface",
+    ],
+)
+
 envoy_cc_test_library(
     name = "add_body_filter_config_lib",
     srcs = [

test/integration/filters/test_listener_filter.cc

@@ -0,0 +1,34 @@
+#include "test/integration/filters/test_listener_filter.h"
+
+namespace Envoy {
+
+/**
+ * Config registration for the test filter.
+ */
+class TestInspectorConfigFactory : public Server::Configuration::NamedListenerFilterConfigFactory {
+public:
+  // NamedListenerFilterConfigFactory
+  Network::ListenerFilterFactoryCb createListenerFilterFactoryFromProto(
+      const Protobuf::Message& /*message*/,
+      const Network::ListenerFilterMatcherSharedPtr& listener_filter_matcher,
+      Server::Configuration::ListenerFactoryContext& /*context*/) override {
+    return [listener_filter_matcher](Network::ListenerFilterManager& filter_manager) -> void {
+      filter_manager.addAcceptFilter(listener_filter_matcher,
+                                     std::make_unique<TestListenerFilter>());
+    };
+  }
+
+  ProtobufTypes::MessagePtr createEmptyConfigProto() override {
+    return ProtobufTypes::MessagePtr{new Envoy::ProtobufWkt::Struct()};
+  }
+
+  std::string name() const override { return "envoy.filters.listener.test"; }
+};
+
+absl::Mutex TestListenerFilter::alpn_lock_;
+std::string TestListenerFilter::alpn_;
+
+REGISTER_FACTORY(TestInspectorConfigFactory,
+                 Server::Configuration::NamedListenerFilterConfigFactory){"envoy.listener.test"};
+
+} // namespace Envoy

test/integration/filters/test_listener_filter.h

@@ -0,0 +1,35 @@
+#include "envoy/registry/registry.h"
+#include "envoy/server/filter_config.h"
+
+namespace Envoy {
+/**
+ * Test listener filter which sets the ALPN to a manually configured string.
+ */
+class TestListenerFilter : public Network::ListenerFilter {
+public:
+  TestListenerFilter() = default;
+
+  // Network::ListenerFilter
+  Network::FilterStatus onAccept(Network::ListenerFilterCallbacks& cb) override {
+    absl::MutexLock m(&alpn_lock_);
+    ASSERT(!alpn_.empty());
+    cb.socket().setRequestedApplicationProtocols({alpn_});
+    alpn_.clear();
+    return Network::FilterStatus::Continue;
+  }
+  Network::FilterStatus onData(Network::ListenerFilterBuffer&) override {
+    return Network::FilterStatus::Continue;
+  }
+  size_t maxReadBytes() const override { return 0; }
+
+  static void setAlpn(std::string alpn) {
+    absl::MutexLock m(&alpn_lock_);
+    alpn_ = alpn;
+  }
+
+private:
+  static absl::Mutex alpn_lock_;
+  static std::string alpn_;
+};
+
+} // namespace Envoy

test/integration/xds_integration_test.cc

@@ -3,6 +3,7 @@
 
 #include "source/common/buffer/buffer_impl.h"
 
+#include "test/integration/filters/test_listener_filter.h"
 #include "test/integration/http_integration.h"
 #include "test/integration/http_protocol_integration.h"
 #include "test/integration/ssl_utility.h"
@@ -140,8 +141,7 @@ class LdsInplaceUpdateTcpProxyIntegrationTest
 
   void initialize() override {
     config_helper_.renameListener("tcp");
-    std::string tls_inspector_config = ConfigHelper::tlsInspectorFilter();
-    config_helper_.addListenerFilter(tls_inspector_config);
+    config_helper_.addListenerFilter(ConfigHelper::testInspectorFilter());
 
     config_helper_.addSslConfig();
     config_helper_.addConfigModifier([](envoy::config::bootstrap::v3::Bootstrap& bootstrap) {
@@ -168,6 +168,7 @@ class LdsInplaceUpdateTcpProxyIntegrationTest
                                                                 const std::string& request,
                                                                 std::string& response) {
     Buffer::OwnedImpl buffer(request);
+    TestListenerFilter::setAlpn(alpn);
     return std::make_unique<RawConnectionDriver>(
         lookupPort("tcp"), buffer,
         [&response](Network::ClientConnection&, const Buffer::Instance& data) -> void {
@@ -298,8 +299,7 @@ class LdsInplaceUpdateHttpIntegrationTest
     setUpstreamCount(2);
 
     config_helper_.renameListener("http");
-    std::string tls_inspector_config = ConfigHelper::tlsInspectorFilter();
-    config_helper_.addListenerFilter(tls_inspector_config);
+    config_helper_.addListenerFilter(ConfigHelper::testInspectorFilter());
     config_helper_.addSslConfig();
     config_helper_.addConfigModifier(
         [&](envoy::extensions::filters::network::http_connection_manager::v3::HttpConnectionManager&
@@ -361,6 +361,7 @@ class LdsInplaceUpdateHttpIntegrationTest
   }
 
   IntegrationCodecClientPtr createHttpCodec(const std::string& alpn) {
+    TestListenerFilter::setAlpn(alpn);
     auto ssl_conn = dispatcher_->createClientConnection(
         address_, Network::Address::InstanceConstSharedPtr(),
         context_->createTransportSocket(std::make_shared<Network::TransportSocketOptionsImpl>(