[WIP] Add the connection.requested_server_name attribute to the TCP read filter

include/istio/control/http/check_data.h

@@ -48,7 +48,7 @@ class CheckData {
   virtual bool IsMutualTLS() const = 0;
 
   // Get requested server name, SNI in case of TLS
-  virtual std::string GetRequestedServerName() const = 0;
+  virtual bool GetRequestedServerName(std::string *name) const = 0;
 
   // These headers are extracted into top level attributes.
   // This is for standard HTTP headers.  It supports both HTTP/1.1 and HTTP2

include/istio/control/tcp/check_data.h

@@ -38,7 +38,7 @@ class CheckData {
   virtual bool IsMutualTLS() const = 0;
 
   // Get requested server name, SNI in case of TLS
-  virtual std::string GetRequestedServerName() const = 0;
+  virtual bool GetRequestedServerName(std::string* name) const = 0;
 
   // Get downstream tcp connection id.
   virtual std::string GetConnectionId() const = 0;

src/envoy/http/mixer/check_data.cc

@@ -77,12 +77,8 @@ std::map<std::string, std::string> CheckData::GetRequestHeaders() const {
 
 bool CheckData::IsMutualTLS() const { return Utils::IsMutualTLS(connection_); }
 
-std::string CheckData::GetRequestedServerName() const {
-  if (connection_) {
-    return std::string(connection_->requestedServerName());
-  }
-
-  return "";
+bool CheckData::GetRequestedServerName(std::string* name) const {
+  return Utils::GetRequestedServerName(connection_, name);
 }
 
 bool CheckData::FindHeaderByType(HttpCheckData::HeaderType header_type,

src/envoy/tcp/mixer/filter.cc

@@ -158,7 +158,7 @@ bool Filter::IsMutualTLS() const {
 }
 
 std::string Filter::GetRequestedServerName() const {
-  return std::string(filter_callbacks_->connection().requestedServerName());
+  return Utils::GetRequestedServerName(&filter_callbacks_->connection(), name);
 }
 
 bool Filter::GetDestinationIpPort(std::string* str_ip, int* port) const {

src/envoy/utils/utils.cc

@@ -116,6 +116,16 @@ bool IsMutualTLS(const Network::Connection* connection) {
          connection->ssl()->peerCertificatePresented();
 }
 
+bool GetRequestedServerName(const Network::Connection* connection,
+                            std::string* name) {
+  if (connection) {
+    *name = std::string(connection->requestedServerName());
+    return true;
+  }
+
+  return false;
+}
+
 Status ParseJsonMessage(const std::string& json, Message* output) {
   ::google::protobuf::util::JsonParseOptions options;
   options.ignore_unknown_fields = true;

src/envoy/utils/utils.h

@@ -43,6 +43,10 @@ bool GetSourceUser(const Network::Connection* connection, std::string* user);
 // Returns true if connection is mutual TLS enabled.
 bool IsMutualTLS(const Network::Connection* connection);
 
+// Get requested server name, SNI in case of TLS
+bool GetRequestedServerName(const Network::Connection* connection,
+                            std::string* name);
+
 // Parse JSON string into message.
 ::google::protobuf::util::Status ParseJsonMessage(
     const std::string& json, ::google::protobuf::Message* output);

src/istio/control/http/attributes_builder.cc

@@ -157,8 +157,8 @@ void AttributesBuilder::ExtractCheckAttributes(CheckData *check_data) {
   builder.AddBool(utils::AttributeName::kConnectionMtls,
                   check_data->IsMutualTLS());
 
-  std::string requested_server_name = check_data->GetRequestedServerName();
-  if (!requested_server_name.empty()) {
+  std::string requested_server_name;
+  if (check_data->GetRequestedServerName(&requested_server_name) {
     builder.AddString(utils::AttributeName::kConnectionRequestedServerName,
                       requested_server_name);
   }

src/istio/control/http/attributes_builder_test.cc

@@ -292,8 +292,11 @@ TEST(AttributesBuilderTest, TestCheckAttributes) {
   EXPECT_CALL(mock_data, IsMutualTLS()).WillOnce(Invoke([]() -> bool {
     return true;
   }));
-  EXPECT_CALL(mock_data, GetRequestedServerName())
-      .WillOnce(testing::Return("www.google.com"));
+  EXPECT_CALL(mock_data, GetRequestedServerName(_))
+      .WillOnce(Invoke([](std::string *name) -> bool {
+        *name = "www.google.com";
+        return true;
+      }));
   EXPECT_CALL(mock_data, GetRequestHeaders())
       .WillOnce(Invoke([]() -> std::map<std::string, std::string> {
         std::map<std::string, std::string> map;
@@ -349,8 +352,11 @@ TEST(AttributesBuilderTest, TestCheckAttributesWithAuthNResult) {
   EXPECT_CALL(mock_data, IsMutualTLS()).WillOnce(Invoke([]() -> bool {
     return true;
   }));
-  EXPECT_CALL(mock_data, GetRequestedServerName())
-      .WillOnce(testing::Return("www.google.com"));
+  EXPECT_CALL(mock_data, GetRequestedServerName(_))
+      .WillOnce(Invoke([](std::string *name) -> bool {
+        *name = "www.google.com";
+        return true;
+      }));
   EXPECT_CALL(mock_data, GetRequestHeaders())
       .WillOnce(Invoke([]() -> std::map<std::string, std::string> {
         std::map<std::string, std::string> map;

src/istio/control/http/mock_check_data.h

@@ -44,7 +44,7 @@ class MockCheckData : public CheckData {
   MOCK_CONST_METHOD1(GetAuthenticationResult,
                      bool(istio::authn::Result *result));
   MOCK_CONST_METHOD0(IsMutualTLS, bool());
-  MOCK_CONST_METHOD0(GetRequestedServerName, std::string());
+  MOCK_CONST_METHOD0(GetRequestedServerName, bool(std::string *name));
 };
 
 // The mock object for HeaderUpdate interface.

src/istio/control/tcp/attributes_builder.cc

@@ -51,8 +51,8 @@ void AttributesBuilder::ExtractCheckAttributes(CheckData* check_data) {
   builder.AddBool(utils::AttributeName::kConnectionMtls,
                   check_data->IsMutualTLS());
 
-  std::string requested_server_name = check_data->GetRequestedServerName();
-  if (!requested_server_name.empty()) {
+  std::string requested_server_name;
+  if (check_data->GetRequestedServerName(&requested_server_name) {
     builder.AddString(utils::AttributeName::kConnectionRequestedServerName,
                       requested_server_name);
   }

src/istio/control/tcp/attributes_builder_test.cc

@@ -311,9 +311,11 @@ TEST(AttributesBuilderTest, TestCheckAttributes) {
         return true;
       }));
   EXPECT_CALL(mock_data, GetConnectionId()).WillOnce(Return("1234-5"));
-  EXPECT_CALL(mock_data, GetRequestedServerName())
-      .WillOnce(Return("www.google.com"));
-
+  EXPECT_CALL(mock_data, GetRequestedServerName(_))
+      .WillOnce(Invoke([](std::string* name) -> bool {
+        *name = "www.google.com";
+        return true;
+      }));
   RequestContext request;
   AttributesBuilder builder(&request);
   builder.ExtractCheckAttributes(&mock_data);

src/istio/control/tcp/mock_check_data.h

@@ -29,7 +29,7 @@ class MockCheckData : public CheckData {
   MOCK_CONST_METHOD2(GetSourceIpPort, bool(std::string* ip, int* port));
   MOCK_CONST_METHOD1(GetSourceUser, bool(std::string* user));
   MOCK_CONST_METHOD0(IsMutualTLS, bool());
-  MOCK_CONST_METHOD0(GetRequestedServerName, std::string());
+  MOCK_CONST_METHOD0(GetRequestedServerName, bool(std::string* name));
   MOCK_CONST_METHOD0(GetConnectionId, std::string());
 };