--- /dev/null
+/*
+ *
+ * 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.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_SECURITY_TRANSPORT_TARGET_AUTHORITY_TABLE_H
+#define GRPC_CORE_LIB_SECURITY_TRANSPORT_TARGET_AUTHORITY_TABLE_H
+
+#include <grpc/support/port_platform.h>
+
+#include "src/core/lib/slice/slice_hash_table.h"
+
+namespace grpc_core {
+
+/// A hash table mapping target addresses to authorities.
+typedef SliceHashTable<UniquePtr<char>> TargetAuthorityTable;
+
+/// Returns a channel argument containing \a table.
+grpc_arg CreateTargetAuthorityTableChannelArg(TargetAuthorityTable* table);
+
+/// Returns the target authority table from \a args or nullptr.
+TargetAuthorityTable* FindTargetAuthorityTableInArgs(
+ const grpc_channel_args* args);
+
+} // namespace grpc_core
+
+#endif /* GRPC_CORE_LIB_SECURITY_TRANSPORT_TARGET_AUTHORITY_TABLE_H */