ext_authz: do the authentication even the direct response is set

docs/root/version_history/current.rst

@@ -42,6 +42,7 @@ Bug Fixes
 * access log: fix ``%UPSTREAM_CLUSTER%`` when used in http upstream access logs. Previously, it was always logging as an unset value.
 * aws request signer: fix the AWS Request Signer extension to correctly normalize the path and query string to be signed according to AWS' guidelines, so that the hash on the server side matches. See `AWS SigV4 documentaion <https://docs.aws.amazon.com/general/latest/gr/sigv4-create-canonical-request.html>`_.
 * cluster: delete pools when they're idle to fix unbounded memory use when using PROXY protocol upstream with tcp_proxy. This behavior can be temporarily reverted by setting the ``envoy.reloadable_features.conn_pool_delete_when_idle`` runtime guard to false.
+* ext_authz: fixed skipping authentication when returning either a direct response or a redirect. This behavior can be temporarily reverted by setting the ``envoy.reloadable_features.http_ext_authz_do_not_skip_direct_response_and_redirect`` runtime guard to false.
 * hcm: remove deprecation for :ref:`xff_num_trusted_hops <envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.xff_num_trusted_hops>` and forbid mixing ip detection extensions with old related knobs.
 * listener: fixed an issue on Windows where connections are not handled by all worker threads.
 * xray: fix the AWS X-Ray tracer bug where span's error, fault and throttle information was not reported properly as per the `AWS X-Ray documentation <https://docs.aws.amazon.com/xray/latest/devguide/xray-api-segmentdocuments.html>`_. Before this fix, server error was reported under 'annotations' section of the segment data.

source/common/router/config_impl.cc

@@ -1012,15 +1012,9 @@ void RouteEntryImplBase::validateClusters(
 void RouteEntryImplBase::traversePerFilterConfig(
     const std::string& filter_name,
     std::function<void(const Router::RouteSpecificFilterConfig&)> cb) const {
-  const Router::RouteEntry* route_entry = routeEntry();
-
-  // TODO(soulxu): This has similar bug with https://github.com/envoyproxy/envoy/issues/17377
-  // it should be fixed.
-  if (route_entry != nullptr) {
-    auto maybe_vhost_config = vhost_.perFilterConfig(filter_name);
-    if (maybe_vhost_config != nullptr) {
-      cb(*maybe_vhost_config);
-    }
+  auto maybe_vhost_config = vhost_.perFilterConfig(filter_name);
+  if (maybe_vhost_config != nullptr) {
+    cb(*maybe_vhost_config);
   }
 
   auto maybe_route_config = per_filter_configs_.get(filter_name);

source/common/runtime/runtime_features.cc

@@ -72,6 +72,7 @@ constexpr const char* runtime_features[] = {
     "envoy.reloadable_features.health_check.immediate_failure_exclude_from_cluster",
     "envoy.reloadable_features.http2_consume_stream_refused_errors",
     "envoy.reloadable_features.http2_skip_encoding_empty_trailers",
+    "envoy.reloadable_features.http_ext_authz_do_not_skip_direct_response_and_redirect",
     "envoy.reloadable_features.http_transport_failure_reason_in_body",
     "envoy.reloadable_features.improved_stream_limit_handling",
     "envoy.reloadable_features.internal_redirects_with_body",

source/extensions/filters/http/ext_authz/ext_authz.cc

@@ -374,7 +374,10 @@ void Filter::continueDecoding() {
 }
 
 Filter::PerRouteFlags Filter::getPerRouteFlags(const Router::RouteConstSharedPtr& route) const {
-  if (route == nullptr || route->routeEntry() == nullptr) {
+  if (route == nullptr ||
+      (!Runtime::runtimeFeatureEnabled(
+           "envoy.reloadable_features.http_ext_authz_do_not_skip_direct_response_and_redirect") &&
+       route->routeEntry() == nullptr)) {
     return PerRouteFlags{true /*skip_check_*/, false /*skip_request_body_buffering_*/};
   }
 

test/common/router/config_impl_test.cc

@@ -7988,6 +7988,32 @@ TEST_F(PerFilterConfigsTest, RouteLocalTypedConfig) {
   checkEach(yaml, 123, expected_traveled_config);
 }
 
+TEST_F(PerFilterConfigsTest, RouteLocalTypedConfigWithDirectResponse) {
+  const std::string yaml = R"EOF(
+virtual_hosts:
+  - name: bar
+    domains: ["*"]
+    routes:
+      - match: { prefix: "/" }
+        direct_response:
+          status: 200
+        typed_per_filter_config:
+          test.filter:
+            "@type": type.googleapis.com/google.protobuf.Timestamp
+            value:
+              seconds: 123
+    typed_per_filter_config:
+      test.filter:
+        "@type": type.googleapis.com/google.protobuf.Struct
+        value:
+          seconds: 456
+)EOF";
+
+  factory_context_.cluster_manager_.initializeClusters({"baz"}, {});
+  absl::InlinedVector<uint32_t, 3> expected_traveled_config({456, 123});
+  checkEach(yaml, 123, expected_traveled_config);
+}
+
 TEST_F(PerFilterConfigsTest, DEPRECATED_FEATURE_TEST(WeightedClusterConfig)) {
   TestDeprecatedV2Api _deprecated_v2_api;
   const std::string yaml = R"EOF(

test/extensions/filters/http/ext_authz/BUILD

@@ -32,6 +32,7 @@ envoy_extension_cc_test(
         "//test/mocks/runtime:runtime_mocks",
         "//test/mocks/tracing:tracing_mocks",
         "//test/mocks/upstream:cluster_manager_mocks",
+        "//test/test_common:test_runtime_lib",
         "//test/test_common:utility_lib",
         "@envoy_api//envoy/config/core/v3:pkg_cc_proto",
         "@envoy_api//envoy/extensions/filters/http/ext_authz/v3:pkg_cc_proto",

test/extensions/filters/http/ext_authz/ext_authz_integration_test.cc

@@ -700,6 +700,47 @@ TEST_P(ExtAuthzHttpIntegrationTest, DefaultCaseSensitiveStringMatcher) {
   ASSERT_TRUE(header_entry.empty());
 }
 
+TEST_P(ExtAuthzHttpIntegrationTest, DirectReponse) {
+  config_helper_.addConfigModifier(
+      [](envoy::extensions::filters::network::http_connection_manager::v3::HttpConnectionManager&
+             hcm) {
+        auto* virtual_hosts = hcm.mutable_route_config()->mutable_virtual_hosts(0);
+        virtual_hosts->mutable_routes(0)->clear_route();
+        envoy::config::route::v3::Route* route = virtual_hosts->mutable_routes(0);
+        route->mutable_direct_response()->set_status(204);
+      });
+
+  initializeConfig();
+  HttpIntegrationTest::initialize();
+  initiateClientConnection();
+  waitForExtAuthzRequest();
+
+  ASSERT_TRUE(response_->waitForEndStream());
+  EXPECT_TRUE(response_->complete());
+  EXPECT_EQ("204", response_->headers().Status()->value().getStringView());
+}
+
+TEST_P(ExtAuthzHttpIntegrationTest, RedirectResponse) {
+  config_helper_.addConfigModifier(
+      [](envoy::extensions::filters::network::http_connection_manager::v3::HttpConnectionManager&
+             hcm) {
+        auto* virtual_hosts = hcm.mutable_route_config()->mutable_virtual_hosts(0);
+        virtual_hosts->mutable_routes(0)->clear_route();
+        envoy::config::route::v3::Route* route = virtual_hosts->mutable_routes(0);
+        route->mutable_redirect()->set_path_redirect("/redirect");
+      });
+
+  initializeConfig();
+  HttpIntegrationTest::initialize();
+  initiateClientConnection();
+  waitForExtAuthzRequest();
+
+  ASSERT_TRUE(response_->waitForEndStream());
+  EXPECT_TRUE(response_->complete());
+  EXPECT_EQ("301", response_->headers().Status()->value().getStringView());
+  EXPECT_EQ("http://host/redirect", response_->headers().getLocationValue());
+}
+
 class ExtAuthzLocalReplyIntegrationTest : public HttpIntegrationTest,
                                           public TestWithParam<Network::Address::IpVersion> {
 public:

test/extensions/filters/http/ext_authz/ext_authz_test.cc

@@ -26,6 +26,7 @@
 #include "test/mocks/tracing/mocks.h"
 #include "test/mocks/upstream/cluster_manager.h"
 #include "test/test_common/printers.h"
+#include "test/test_common/test_runtime.h"
 #include "test/test_common/utility.h"
 
 #include "gmock/gmock.h"
@@ -1603,14 +1604,30 @@ TEST_P(HttpFilterTestParam, DisabledOnRouteWithRequestBody) {
   EXPECT_EQ(Http::FilterTrailersStatus::Continue, filter_->decodeTrailers(request_trailers_));
 }
 
-// Test that the request continues when the filter_callbacks has no route.
+// Test that authentication will do when the filter_callbacks has no route.(both
+// direct response and redirect have no route)
 TEST_P(HttpFilterTestParam, NoRoute) {
-  EXPECT_CALL(*filter_callbacks_.route_, routeEntry()).WillOnce(Return(nullptr));
-  EXPECT_EQ(Http::FilterHeadersStatus::Continue, filter_->decodeHeaders(request_headers_, false));
+  EXPECT_CALL(*filter_callbacks_.route_, routeEntry()).WillRepeatedly(Return(nullptr));
+  prepareCheck();
+  EXPECT_CALL(*client_, check(_, _, _, _));
+  EXPECT_EQ(Http::FilterHeadersStatus::StopAllIterationAndWatermark,
+            filter_->decodeHeaders(request_headers_, false));
   EXPECT_EQ(Http::FilterDataStatus::Continue, filter_->decodeData(data_, false));
   EXPECT_EQ(Http::FilterTrailersStatus::Continue, filter_->decodeTrailers(request_trailers_));
 }
 
+// Test that the authentication will be skipped when the filter_callbacks has no route(both
+// direct response and redirect have no route) when the runtime flag
+// `envoy.reloadable_features.http_ext_authz_do_not_skip_direct_response_and_redirect` is false.
+TEST_P(HttpFilterTestParam, NoRouteWithSkipAuth) {
+  TestScopedRuntime scoped_runtime;
+  Runtime::LoaderSingleton::getExisting()->mergeValues(
+      {{"envoy.reloadable_features.http_ext_authz_do_not_skip_direct_response_and_redirect",
+        "false"}});
+  EXPECT_CALL(*filter_callbacks_.route_, routeEntry()).WillOnce(Return(nullptr));
+  EXPECT_EQ(Http::FilterHeadersStatus::Continue, filter_->decodeHeaders(request_headers_, false));
+}
+
 // Test that the request is stopped till there is an OK response back after which it continues on.
 TEST_P(HttpFilterTestParam, OkResponse) {
   InSequence s;