diff --git a/os/libs/common.lua b/os/libs/common.lua
index 23a27ec..bb3f031 100644
--- a/os/libs/common.lua
+++ b/os/libs/common.lua
@@ -52,6 +52,7 @@ function is_auth()
 	local f = io.open(TUNNEL_KEYCHAIN, "w")
 	if f then
 		f:write(sessionid)
+		f:close()
 	end
 	return true
 end
@@ -60,4 +61,4 @@ function auth_or_die(msg)
 	if(is_auth() == false) then
 		die(msg)
 	end
-end
\ No newline at end of file
+end