MSC_Tests.ttcn: introduce TC_proc_ss_for_unknown_session

The idea of this test case is to check that OsmoMSC properly
rejects GSUP PROC_SS messages for unknown sessions.

As it turned out, OsmoMSC doesn't send GSUP PROC_SS ERROR
as expected. The fix has been submitted.

Change-Id: Ie267ee174c5061cd3fc102a2824abe03d73f3aac
Related: OS#2931

1 files changed, 43 insertions, 0 deletions

diff --git a/msc/MSC_Tests.ttcn b/msc/MSC_Tests.ttcn
index b8f9fd7d..f9b2d032 100644
--- a/msc/MSC_Tests.ttcn
+++ b/msc/MSC_Tests.ttcn
@@ -3507,6 +3507,48 @@ testcase TC_mt_ussd_for_unknown_subscr() runs on MTC_CT {
 	vc_conn.done;
 }
 
+/* MT (network-originated) USSD for unknown session */
+friend function f_tc_proc_ss_for_unknown_session(charstring id, BSC_ConnHdlrPars pars)
+runs on BSC_ConnHdlr {
+	var OCT4 sid := '20000333'O;
+
+	f_init_handler(pars);
+
+	/* Perform location update */
+	f_perform_lu();
+
+	f_ran_register_imsi(g_pars.imsi, 'FFFFFFFF'O);
+	f_create_gsup_expect(hex2str(g_pars.imsi));
+
+	/* Request referencing a non-existing SS session */
+	var template (value) GSUP_PDU gsup_req := ts_GSUP_PROC_SS_REQ(
+		imsi := g_pars.imsi,
+		sid := sid,
+		state := OSMO_GSUP_SESSION_STATE_CONTINUE,
+		ss := f_rnd_octstring(23)
+	);
+
+	/* Error with some cause value */
+	var template GSUP_PDU gsup_rsp := tr_GSUP_PROC_SS_ERR(
+		imsi := g_pars.imsi,
+		sid := sid,
+		state := OSMO_GSUP_SESSION_STATE_END,
+		cause := ? /* FIXME: introduce an enumerated type! */
+	);
+
+	/* Initiate a MT USSD notification */
+	GSUP.send(gsup_req);
+
+	/* Expect GSUP PROC_SS_ERROR message */
+	f_expect_gsup_msg(gsup_rsp);
+}
+testcase TC_proc_ss_for_unknown_session() runs on MTC_CT {
+	var BSC_ConnHdlr vc_conn;
+	f_init();
+	vc_conn := f_start_handler(refers(f_tc_proc_ss_for_unknown_session), 110);
+	vc_conn.done;
+}
+
 
 /* A5/1 only permitted on network side; attempt an invalid CIPHER MODE COMPLETE with A5/3 which MSC should reject. */
 private function f_tc_cipher_complete_with_invalid_cipher(charstring id, BSC_ConnHdlrPars pars) runs on BSC_ConnHdlr {
@@ -5356,6 +5398,7 @@ control {
 	execute( TC_lu_and_ss_session_timeout() );
 
 	execute( TC_mt_ussd_for_unknown_subscr() );
+	execute( TC_proc_ss_for_unknown_session() );
 
 	execute( TC_cipher_complete_with_invalid_cipher() );
 	execute( TC_cipher_complete_1_without_cipher() );