msc: inter-MSC HO test: use CGI cell ID, not LAI

Fixes inter-MSC handover tests: in the inter-MSC 'Handover Required', do
not send a LAI cell identifier, but a CGI one.

This is analogous to the fix applied to inter-BSC HO in
I48276acf923626db171683dfa03ef43614a71380.

Rationale:

As explained in OS#5188, 3GPP TS 48.008 allows a LAI identification only
in the Cell Identifier List IE, but not in the single Cell Identifier
IE.

In the inter-MSC HO test's Handover Required message, we so far send a
LAI identifier in a List IE to osmo-msc. And so far, osmo-msc simply
echos that in the Handover Request message's single Cell Id IE.

The LAI is, as actually defined in the spec, omitted from the single IE
in deps/titan.ProtocolModules.BSSMAP/src/BSSAP_Types.ttcn, and when
osmo-msc sends the non-standard LAI Id, ttcn3 fails to parse the BSSMAP
Handover Request message: the Cell Identifier IE gets wrong values, and
all remaining IEs are parsed as 'omit' even though they are present on
the wire. So as long as osmo-msc sends back a LAI Id, we cannot sanely
verify the Handover Request received from the MSC.

The CGI identifier type is supported in both IEs. So when the test sends
a CGI identifier in the Handover Required, osmo-msc will also reflect a
CGI identifier in the Handover Request, and ttcn3 parsing works.

Related: OS#5188 SYS#5324
Change-Id: I525b5deaa9634fcdb63fbd2c97c767aff045767c

1 files changed, 1 insertions, 1 deletions

diff --git a/msc/MSC_Tests.ttcn b/msc/MSC_Tests.ttcn
index e548c5c5..a165d5cc 100644
--- a/msc/MSC_Tests.ttcn
+++ b/msc/MSC_Tests.ttcn
@@ -5985,7 +5985,7 @@ private function f_tc_ho_inter_msc_out(charstring id, BSC_ConnHdlrPars pars) run
 	var BssmapCause cause := enum2int(cause_val);
 
 	var template BSSMAP_FIELD_CellIdentificationList cil;
-	cil := { cIl_LAI := { ts_BSSMAP_CI_LAI('017'H, '017'H, 1) } };
+	cil := { cIl_CGI := { ts_BSSMAP_CI_CGI('017'H, '017'H, 1, 1) } };
 
 	/* old BSS sends Handover Required */
 	BSSAP.send(ts_BSSMAP_HandoverRequired(cause, cil));