1 files changed, 57 insertions, 0 deletions
diff --git a/src/core/lib/security/transport/lb_targets_info.cc b/src/core/lib/security/transport/lb_targets_info.cc
new file mode 100644
index 0000000000..947fc1addf
--- /dev/null
+++ b/src/core/lib/security/transport/lb_targets_info.cc
@@ -0,0 +1,57 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/support/log.h>
+
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/security/transport/lb_targets_info.h"
+
+/* Channel arg key for the mapping of LB server addresses to their names for
+ * secure naming purposes. */
+#define GRPC_ARG_LB_SECURE_NAMING_MAP "grpc.lb_secure_naming_map"
+
+static void *targets_info_copy(void *p) {
+  return grpc_slice_hash_table_ref((grpc_slice_hash_table *)p);
+}
+static void targets_info_destroy(grpc_exec_ctx *exec_ctx, void *p) {
+  grpc_slice_hash_table_unref(exec_ctx, (grpc_slice_hash_table *)p);
+}
+static int targets_info_cmp(void *a, void *b) {
+  return grpc_slice_hash_table_cmp((const grpc_slice_hash_table *)a,
+                                   (const grpc_slice_hash_table *)b);
+}
+static const grpc_arg_pointer_vtable server_to_balancer_names_vtable = {
+    targets_info_copy, targets_info_destroy, targets_info_cmp};
+
+grpc_arg grpc_lb_targets_info_create_channel_arg(
+    grpc_slice_hash_table *targets_info) {
+  return grpc_channel_arg_pointer_create((char *)GRPC_ARG_LB_SECURE_NAMING_MAP,
+                                         targets_info,
+                                         &server_to_balancer_names_vtable);
+}
+
+grpc_slice_hash_table *grpc_lb_targets_info_find_in_args(
+    const grpc_channel_args *args) {
+  const grpc_arg *targets_info_arg =
+      grpc_channel_args_find(args, GRPC_ARG_LB_SECURE_NAMING_MAP);
+  if (targets_info_arg != NULL) {
+    GPR_ASSERT(targets_info_arg->type == GRPC_ARG_POINTER);
+    return (grpc_slice_hash_table *)targets_info_arg->value.pointer.p;
+  }
+  return NULL;
+}