Refuse Emergency Calls by IMEI with proper CM SERVICE REJECT Cause
OsmoMSC rejects an Emergency Call with IMEI as mobile identity with
"semantically incorrect message" which is clearly wrong. According to TS
24.008 4.5.1.5 we should reject with cause 5 "IMEI not accepted"
Found with TTCN-3 test case MSC_Tests.TC_emerg_call_imei
Change-Id: I2f7ab0e32b914a112c0b17c523d149ccd0299099
Closes: #2866
diff --git a/src/libmsc/gsm_04_08.c b/src/libmsc/gsm_04_08.c
index 54e8bee..90669e1 100644
--- a/src/libmsc/gsm_04_08.c
+++ b/src/libmsc/gsm_04_08.c
@@ -672,16 +672,22 @@
gsm48_mi_to_string(mi_string, sizeof(mi_string), mi, mi_len);
mi_type = mi[0] & GSM_MI_TYPE_MASK;
+ DEBUGPC(DMM, "serv_type=0x%02x MI(%s)=%s\n",
+ req->cm_service_type, gsm48_mi_type_name(mi_type), mi_string);
- if (mi_type == GSM_MI_TYPE_IMSI) {
- DEBUGPC(DMM, "serv_type=0x%02x MI(%s)=%s\n",
- req->cm_service_type, gsm48_mi_type_name(mi_type),
- mi_string);
- } else if (mi_type == GSM_MI_TYPE_TMSI) {
- DEBUGPC(DMM, "serv_type=0x%02x MI(%s)=%s\n",
- req->cm_service_type, gsm48_mi_type_name(mi_type),
- mi_string);
- } else {
+ switch (mi_type) {
+ case GSM_MI_TYPE_IMSI:
+ case GSM_MI_TYPE_TMSI:
+ /* continue below */
+ break;
+ case GSM_MI_TYPE_IMEI:
+ if (req->cm_service_type == GSM48_CMSERV_EMERGENCY) {
+ /* We don't do emergency calls by IMEI */
+ LOGP(DMM, LOGL_NOTICE, "<- CM SERVICE REQUEST(IMEI=%s) rejected\n", mi_string);
+ return msc_gsm48_tx_mm_serv_rej(conn, GSM48_REJECT_IMEI_NOT_ACCEPTED);
+ }
+ /* fall-through for non-emergency setup */
+ default:
DEBUGPC(DMM, "mi_type is not expected: %d\n", mi_type);
return msc_gsm48_tx_mm_serv_rej(conn,
GSM48_REJECT_INCORRECT_MESSAGE);