add rua_helper.[ch] missing from previous commit
diff --git a/src/tests/rua_helper.h b/src/tests/rua_helper.h
new file mode 100644
index 0000000..ca2f4e8
--- /dev/null
+++ b/src/tests/rua_helper.h
@@ -0,0 +1,9 @@
+#pragma once
+
+#include <stdint.h>
+#include <osmocom/core/msgb.h>
+
+struct msgb *rua_new_udt(struct msgb *inmsg);
+struct msgb *rua_new_conn(int is_ps, uint32_t context_id, struct msgb *inmsg);
+struct msgb *rua_new_dt(int is_ps, uint32_t context_id, struct msgb *inmsg);
+struct msgb *rua_new_disc(int is_ps, uint32_t context_id, struct msgb *inmsg);