diff --git a/server/tools/protobuild/cs_proto.proto b/server/tools/protobuild/cs_proto.proto
index 5c93373d..40ac386c 100755
--- a/server/tools/protobuild/cs_proto.proto
+++ b/server/tools/protobuild/cs_proto.proto
@@ -70,6 +70,7 @@ message CMKcpHandshake
     optional string account_id = 2; //账号id
     optional string session_id = 3; //session id
     optional string team_uuid = 4; //保留
+    optional int32 secret_key_place = 5; //私钥存放位置 0：存在用户协议前(老) 1：存在kcp底层协议头之后(新)
 }
 
 message SMKcpHandshake