mobile: Adds an API to set additional socket options (envoyproxy#39360)

Signed-off-by: Ali Beyad <[email protected]>

Author: abeyad

mobile/library/cc/engine_builder.cc

@@ -150,6 +150,12 @@ EngineBuilder& EngineBuilder::addDnsPreresolveHostnames(const std::vector<std::s
   return *this;
 }
 
+EngineBuilder& EngineBuilder::setAdditionalSocketOptions(
+    const std::vector<envoy::config::core::v3::SocketOption>& socket_options) {
+  socket_options_ = socket_options;
+  return *this;
+}
+
 EngineBuilder& EngineBuilder::addMaxConnectionsPerHost(int max_connections_per_host) {
   max_connections_per_host_ = max_connections_per_host;
   return *this;
@@ -823,6 +829,11 @@ std::unique_ptr<envoy::config::bootstrap::v3::Bootstrap> EngineBuilder::generate
           absl::StrCat("SO_NET_SERVICE_TYPE = ", ios_network_service_type_));
     }
 #endif
+    for (const auto& socket_option : socket_options_) {
+      envoy::config::core::v3::SocketOption* sock_opt =
+          base_cluster->mutable_upstream_bind_config()->add_socket_options();
+      sock_opt->CopyFrom(socket_option);
+    }
   }
 
   // Set up stats.

mobile/library/cc/engine_builder.h

@@ -7,6 +7,7 @@
 
 #include "envoy/config/bootstrap/v3/bootstrap.pb.h"
 #include "envoy/config/core/v3/base.pb.h"
+#include "envoy/config/core/v3/socket_option.pb.h"
 
 #include "source/common/protobuf/protobuf.h"
 
@@ -76,6 +77,9 @@ class EngineBuilder {
   EngineBuilder& enablePlatformCertificatesValidation(bool platform_certificates_validation_on);
 
   EngineBuilder& enableDnsCache(bool dns_cache_on, int save_interval_seconds = 1);
+  // Set additional socket options on the upstream cluster outbound sockets.
+  EngineBuilder& setAdditionalSocketOptions(
+      const std::vector<envoy::config::core::v3::SocketOption>& socket_options);
   // Adds the hostnames that should be pre-resolved by DNS prior to the first request issued for
   // that host. When invoked, any previous preresolve hostname entries get cleared and only the ones
   // provided in the hostnames argument get set.
@@ -201,6 +205,7 @@ class EngineBuilder {
 
   std::vector<NativeFilterConfig> native_filter_chain_;
   std::vector<std::pair<std::string /* host */, uint32_t /* port */>> dns_preresolve_hostnames_;
+  std::vector<envoy::config::core::v3::SocketOption> socket_options_;
 
   std::vector<std::pair<std::string, bool>> runtime_guards_;
   std::vector<std::pair<std::string, bool>> restart_runtime_guards_;

mobile/test/cc/unit/envoy_config_test.cc

@@ -386,6 +386,42 @@ TEST(TestConfig, UdpSocketSendBufferSize) {
   EXPECT_EQ(snd_buf_option->int_value(), 1452 * 20);
 }
 
+TEST(TestConfig, AdditionalSocketOptions) {
+  EngineBuilder engine_builder;
+  engine_builder.enableHttp3(true);
+  envoy::config::core::v3::SocketOption socket_opt;
+  socket_opt.set_level(SOL_SOCKET);
+  socket_opt.set_name(123);
+  socket_opt.set_int_value(456);
+  socket_opt.mutable_type()->mutable_datagram();
+  engine_builder.setAdditionalSocketOptions({socket_opt});
+
+  std::unique_ptr<Bootstrap> bootstrap = engine_builder.generateBootstrap();
+  Cluster const* base_cluster = nullptr;
+  for (const Cluster& cluster : bootstrap->static_resources().clusters()) {
+    if (cluster.name() == "base") {
+      base_cluster = &cluster;
+      break;
+    }
+  }
+
+  // The base H3 cluster should always be found.
+  ASSERT_THAT(base_cluster, NotNull());
+
+  SocketOption const* additional_socket_opt = nullptr;
+  for (const auto& sock_opt : base_cluster->upstream_bind_config().socket_options()) {
+    if (sock_opt.name() == 123) {
+      additional_socket_opt = &sock_opt;
+      break;
+    }
+  }
+
+  ASSERT_THAT(additional_socket_opt, NotNull());
+  EXPECT_EQ(additional_socket_opt->level(), SOL_SOCKET);
+  EXPECT_TRUE(additional_socket_opt->type().has_datagram());
+  EXPECT_EQ(additional_socket_opt->int_value(), 456);
+}
+
 TEST(TestConfig, EnablePlatformCertificatesValidation) {
   EngineBuilder engine_builder;
   engine_builder.enablePlatformCertificatesValidation(false);