libmsc/gsm_04_11.c: properly handle MMTS indication
According to 3GPP TS 29.002, section 7.6.8.7, MMS (More Messages to Send)
is an optional IE of MT-ForwardSM-Req message which is used by SMSC to
indicate that there are more (multi-part) MT SMS messages to be sent.
The MSC needs to use this indication in order to decide whether to
keep the RAN connection with a given subscriber open.
Related Change-Id: (TTCN) I6308586a70c4fb3254c519330a61a9667372149f
Change-Id: Ic46b04913b2e8cc5d11a39426dcc1bfe11f1d31e
Related: OS#3587
diff --git a/src/libmsc/gsm_04_11.c b/src/libmsc/gsm_04_11.c
index a3b3830..3a3ec8c 100644
--- a/src/libmsc/gsm_04_11.c
+++ b/src/libmsc/gsm_04_11.c
@@ -129,6 +129,28 @@
return msc_a_tx_dtap_to_i(trans->msc_a, msg);
}
+/* Handle MMTS (More Messages to Send) indication */
+static void gsm411_handle_mmts_ind(const struct gsm_trans *trans)
+{
+ int32_t use_count;
+
+ OSMO_ASSERT(trans);
+ OSMO_ASSERT(trans->msc_a);
+
+ use_count = osmo_use_count_by(&trans->msc_a->use_count, MSC_A_USE_SMS_MMTS);
+ OSMO_ASSERT(use_count >= 0); /* Shall not be negative */
+
+ if (trans->sms.sm_rp_mmts_ind && use_count == 0) {
+ LOG_TRANS(trans, LOGL_INFO, "Multi-part SMS delivery is initiated\n");
+ msc_a_get(trans->msc_a, MSC_A_USE_SMS_MMTS);
+ } else if (trans->sms.sm_rp_mmts_ind && use_count > 0) {
+ LOG_TRANS(trans, LOGL_INFO, "Continuing multi-part SMS delivery\n");
+ } else if (!trans->sms.sm_rp_mmts_ind && use_count > 0) {
+ LOG_TRANS(trans, LOGL_INFO, "Multi-part SMS delivery has been completed\n");
+ msc_a_put(trans->msc_a, MSC_A_USE_SMS_MMTS);
+ }
+}
+
/* Paging callback for MT SMS (Paging is triggered by SMC) */
static void mmsms_paging_cb(struct msc_a *msc_a, struct gsm_trans *trans)
{
@@ -141,6 +163,10 @@
/* Associate transaction with established connection */
msc_a_get(msc_a, MSC_A_USE_SMS);
trans->msc_a = msc_a;
+
+ /* Multi-part SMS: handle MMTS (More Messages to Send) indication */
+ gsm411_handle_mmts_ind(trans);
+
/* Confirm successful connection establishment */
gsm411_smc_recv(&trans->sms.smc_inst, GSM411_MMSMS_EST_CNF, NULL, 0);
} else {
@@ -1180,7 +1206,8 @@
/* Low-level function to send raw RP-DATA to a given subscriber */
int gsm411_send_rp_data(struct gsm_network *net, struct vlr_subscr *vsub,
size_t sm_rp_oa_len, const uint8_t *sm_rp_oa,
- size_t sm_rp_ud_len, const uint8_t *sm_rp_ud)
+ size_t sm_rp_ud_len, const uint8_t *sm_rp_ud,
+ bool sm_rp_mmts_ind)
{
struct gsm_trans *trans;
struct msgb *msg;
@@ -1190,6 +1217,11 @@
if (!trans)
return -ENOMEM;
+ /* Multi-part SMS: handle MMTS (More Messages to Send) indication */
+ trans->sms.sm_rp_mmts_ind = sm_rp_mmts_ind;
+ if (trans->msc_a != NULL)
+ gsm411_handle_mmts_ind(trans);
+
/* Allocate a message buffer for to be encoded SMS */
msg = gsm411_msgb_alloc();
if (!msg) {