vlr: optionally send IMEI early to HLR
When 'check-imei-rqd 1 early' is set in the config, send the IMEI to
the HLR before doing the location update with the HLR.
The OsmoHLR documentation referenced in the code will be added in
osmo-hlr.git's Change-Id I2dd4a56f7b8be8b5d0e6fc32e04459e5e278d0a9.
Related: OS#2542
Change-Id: I88283cad23793b475445d814ff49db534cb41244
diff --git a/src/libvlr/vlr.c b/src/libvlr/vlr.c
index f76a7ee..b156b43 100644
--- a/src/libvlr/vlr.c
+++ b/src/libvlr/vlr.c
@@ -1043,6 +1043,8 @@
return -ENODEV;
}
+ /* Dispatch result to vsub->lu_fsm, which will either handle the result by itself (Check IMEI early) or dispatch
+ * it further to lu_compl_vlr_fsm (Check IMEI after LU). */
if (gsup->message_type == OSMO_GSUP_MSGT_CHECK_IMEI_RESULT) {
if (gsup->imei_result == OSMO_GSUP_IMEI_RESULT_ACK)
osmo_fsm_inst_dispatch(vsub->lu_fsm, VLR_ULA_E_HLR_IMEI_ACK, NULL);
diff --git a/src/libvlr/vlr_lu_fsm.c b/src/libvlr/vlr_lu_fsm.c
index 15ab88c..9dff4aa 100644
--- a/src/libvlr/vlr_lu_fsm.c
+++ b/src/libvlr/vlr_lu_fsm.c
@@ -460,7 +460,8 @@
/* TODO: Trace_Subscriber_Activity_VLR */
- if (vlr->cfg.check_imei_rqd) {
+ /* If imeisv_early is enabled: IMEI already retrieved and checked (vlr_loc_upd_node1_pre), don't do it again. */
+ if (vlr->cfg.check_imei_rqd && !vlr->cfg.retrieve_imeisv_early) {
/* Check IMEI VLR */
osmo_fsm_inst_state_chg(fi,
lcvp->assign_tmsi ?
@@ -924,6 +925,39 @@
}
}
+static void vlr_loc_upd_node1_pre(struct osmo_fsm_inst *fi)
+{
+ struct lu_fsm_priv *lfp = lu_fsm_fi_priv(fi);
+ struct vlr_instance *vlr = lfp->vlr;
+
+ LOGPFSM(fi, "%s()\n", __func__);
+
+ if (vlr->cfg.check_imei_rqd && vlr->cfg.retrieve_imeisv_early) {
+ osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_HLR_CHECK_IMEI_EARLY, vlr_timer(lfp->vlr, 3270), 3270);
+ vlr_subscr_tx_req_check_imei(lfp->vsub);
+ } else {
+ vlr_loc_upd_node1(fi);
+ }
+}
+
+/* End of Check_IMEI Procedure. Executed early (before the location update), so we can send the IMEI to the HLR even if
+ * the MS would be rejected in LU. See the "Configuring the Subscribers Create on Demand Feature" section of the OsmoHLR
+ * user manual for a detailed explanation of the use case. */
+static void lu_fsm_wait_hlr_check_imei_early(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+ switch (event) {
+ case VLR_ULA_E_HLR_IMEI_ACK:
+ vlr_loc_upd_node1(fi);
+ break;
+ case VLR_ULA_E_HLR_IMEI_NACK:
+ lu_fsm_failure(fi, GSM48_REJECT_ILLEGAL_ME);
+ break;
+ default:
+ OSMO_ASSERT(0);
+ break;
+ }
+}
+
static void vlr_loc_upd_want_imsi(struct osmo_fsm_inst *fi)
{
struct lu_fsm_priv *lfp = lu_fsm_fi_priv(fi);
@@ -937,7 +971,7 @@
osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_IMSI,
vlr_timer(vlr, 3270), 3270);
vlr->ops.tx_id_req(lfp->msc_conn_ref, GSM_MI_TYPE_IMSI);
- /* will continue at vlr_loc_upd_node1() once IMSI arrives */
+ /* will continue at vlr_loc_upd_node1_pre() once IMSI arrives */
}
static int assoc_lfp_with_sub(struct osmo_fsm_inst *fi, struct vlr_subscr *vsub)
@@ -1043,7 +1077,7 @@
if (!lfp->vsub->imsi[0])
vlr_loc_upd_want_imsi(fi);
else
- vlr_loc_upd_node1(fi);
+ vlr_loc_upd_node1_pre(fi);
}
static void lu_fsm_idle(struct osmo_fsm_inst *fi, uint32_t event,
@@ -1097,7 +1131,7 @@
{
switch (event) {
case VLR_ULA_E_SEND_ID_ACK:
- vlr_loc_upd_node1(fi);
+ vlr_loc_upd_node1_pre(fi);
break;
case VLR_ULA_E_SEND_ID_NACK:
vlr_loc_upd_want_imsi(fi);
@@ -1165,7 +1199,7 @@
switch (event) {
case VLR_ULA_E_ID_IMSI:
vlr_subscr_set_imsi(vsub, mi_string);
- vlr_loc_upd_node1(fi);
+ vlr_loc_upd_node1_pre(fi);
break;
default:
OSMO_ASSERT(0);
@@ -1305,6 +1339,7 @@
S(VLR_ULA_S_WAIT_IMSI) |
S(VLR_ULA_S_WAIT_AUTH) |
S(VLR_ULA_S_WAIT_CIPH) |
+ S(VLR_ULA_S_WAIT_HLR_CHECK_IMEI_EARLY) |
S(VLR_ULA_S_WAIT_HLR_UPD) |
S(VLR_ULA_S_DONE),
.name = OSMO_STRINGIFY(VLR_ULA_S_IDLE),
@@ -1316,6 +1351,7 @@
S(VLR_ULA_S_WAIT_IMSI) |
S(VLR_ULA_S_WAIT_AUTH) |
S(VLR_ULA_S_WAIT_CIPH) |
+ S(VLR_ULA_S_WAIT_HLR_CHECK_IMEI_EARLY) |
S(VLR_ULA_S_WAIT_HLR_UPD) |
S(VLR_ULA_S_DONE),
.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_IMEISV),
@@ -1327,6 +1363,7 @@
.out_state_mask = S(VLR_ULA_S_WAIT_IMSI) |
S(VLR_ULA_S_WAIT_AUTH) |
S(VLR_ULA_S_WAIT_CIPH) |
+ S(VLR_ULA_S_WAIT_HLR_CHECK_IMEI_EARLY) |
S(VLR_ULA_S_DONE),
.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_PVLR),
.action = lu_fsm_wait_pvlr,
@@ -1352,11 +1389,23 @@
.in_event_mask = S(VLR_ULA_E_ID_IMSI),
.out_state_mask = S(VLR_ULA_S_WAIT_AUTH) |
S(VLR_ULA_S_WAIT_CIPH) |
+ S(VLR_ULA_S_WAIT_HLR_CHECK_IMEI_EARLY) |
S(VLR_ULA_S_WAIT_HLR_UPD) |
S(VLR_ULA_S_DONE),
.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_IMSI),
.action = lu_fsm_wait_imsi,
},
+ [VLR_ULA_S_WAIT_HLR_CHECK_IMEI_EARLY] = {
+ .in_event_mask = S(VLR_ULA_E_HLR_IMEI_ACK) |
+ S(VLR_ULA_E_HLR_IMEI_NACK),
+ .out_state_mask = S(VLR_ULA_S_WAIT_AUTH) |
+ S(VLR_ULA_S_WAIT_CIPH) |
+ S(VLR_ULA_S_WAIT_HLR_UPD) |
+ S(VLR_ULA_S_WAIT_LU_COMPL) |
+ S(VLR_ULA_S_DONE),
+ .name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_HLR_CHECK_IMEI_EARLY),
+ .action = lu_fsm_wait_hlr_check_imei_early,
+ },
[VLR_ULA_S_WAIT_HLR_UPD] = {
.in_event_mask = S(VLR_ULA_E_HLR_LU_RES) |
S(VLR_ULA_E_UPD_HLR_COMPL),
diff --git a/src/libvlr/vlr_lu_fsm.h b/src/libvlr/vlr_lu_fsm.h
index 5cf13c7..b5c4a5e 100644
--- a/src/libvlr/vlr_lu_fsm.h
+++ b/src/libvlr/vlr_lu_fsm.h
@@ -9,6 +9,7 @@
VLR_ULA_S_WAIT_AUTH, /* Waiting for Authentication */
VLR_ULA_S_WAIT_CIPH, /* Waiting for Ciphering Complete */
VLR_ULA_S_WAIT_IMSI, /* Waiting for IMSI from MS */
+ VLR_ULA_S_WAIT_HLR_CHECK_IMEI_EARLY, /* Waiting for Check IMEI result from HLR */
VLR_ULA_S_WAIT_HLR_UPD, /* Waiting for end of HLR update */
VLR_ULA_S_WAIT_LU_COMPL,/* Waiting for LU complete */
VLR_ULA_S_WAIT_LU_COMPL_STANDALONE, /* Standalone VLR */