sgs_iface: detect and react to VLR/HLR failure
The HLR (which is connected via the GSUP interface) may fail and
disconnect. On the next location update the VLR will try to talk to the
HLR and fail. This failure event is not communicated towards the SGs
related code and the SGs-association will remain in the LA-PRESENT state
forever. Lets add code to report the problem to the SGs code and trigger
a RESET an the SGs interface.
- Add a flag to report an HLR problem back to the SGs code
- Fix the FSM that controls the reset
- Make sure the all SGs associations are reset when the failure occurs.
Change-Id: Icc7df92879728bc98c85fc1d5d8b4c6246501b12
Related: OS#3859
diff --git a/src/libmsc/sgs_iface.c b/src/libmsc/sgs_iface.c
index d83a730..53ab853 100644
--- a/src/libmsc/sgs_iface.c
+++ b/src/libmsc/sgs_iface.c
@@ -376,15 +376,26 @@
unsigned int new_id_len = 0;
uint8_t resp_msg_type;
+ /* Determine message type that is sent next (needed for logging) */
if (response->accepted)
resp_msg_type = SGSAP_MSGT_LOC_UPD_ACK;
+ else if (response->error)
+ resp_msg_type = SGSAP_MSGT_RESET_IND;
else
resp_msg_type = SGSAP_MSGT_LOC_UPD_REJ;
+ /* Determine MME */
mme = sgs_mme_ctx_by_vsub(vsub, resp_msg_type);
if (!mme)
return;
+ /* Handle error (HLR failure) */
+ if (response->error) {
+ osmo_fsm_inst_dispatch(mme->fi, SGS_VLRR_E_START_RESET, NULL);
+ return;
+ }
+
+ /* Handle LU accept/reject */
if (response->accepted) {
if (vsub->tmsi_new != GSM_RESERVED_TMSI) {
new_id_len = gsm48_generate_mid_from_tmsi(new_id, vsub->tmsi_new);
@@ -1120,6 +1131,10 @@
reset_params.vlr_name_present = true;
reset_ind = gsm29118_create_reset_ind(&reset_params);
sgs_tx(sgc, reset_ind);
+
+ /* Perform a reset of the SGS FSM of all subscribers that are present in the VLR */
+ vlr_sgs_reset(gsm_network->vlr);
+
osmo_fsm_inst_state_chg(fi, SGS_VLRR_ST_WAIT_ACK, sgs->cfg.timer[SGS_STATE_TS11], 11);
break;
default:
@@ -1187,6 +1202,7 @@
static struct osmo_fsm sgs_vlr_reset_fsm = {
.name = "SGs-VLR-RESET",
.states = sgs_vlr_reset_fsm_states,
+ .num_states = ARRAY_SIZE(sgs_vlr_reset_fsm_states),
.allstate_event_mask = S(SGS_VLRR_E_START_RESET),
.allstate_action = sgs_vlr_reset_fsm_allstate,
.timer_cb = sgs_vlr_reset_fsm_timer_cb,