libmsc/gsm_04_11.c: accept MT SMS messages over GSUP

Change-Id: I57357982ca0e51f6722c24a4aa1d0fb3e6caef88
Depends-on: (core) Ibe325c64ae2d6c626b232533bb4cbc65fc2b5d71
Depends-on: (OsmoHLR) I0589ff27933e9bca2bcf93b8259004935778db8f
Related Change-Id: (TTCN) I63a25c8366cce0852df6b628365151661a22a25f
Related: OS#3587

1 files changed, 96 insertions, 0 deletions

diff --git a/src/libmsc/gsm_04_11_gsup.c b/src/libmsc/gsm_04_11_gsup.c
index 5c0107245..f2de95f70 100644
--- a/src/libmsc/gsm_04_11_gsup.c
+++ b/src/libmsc/gsm_04_11_gsup.c
@@ -201,3 +201,99 @@ msg_error:
 		msg_name, msg_is_err ? "Err" : "Res");
 	return -EINVAL;
 }
+
+int gsm411_gsup_mt_fwd_sm_res(struct gsm_trans *trans, uint8_t sm_rp_mr)
+{
+	struct osmo_gsup_message gsup_msg;
+
+	/* Associate logging messages with this subscriber */
+	log_set_context(LOG_CTX_VLR_SUBSCR, trans->vsub);
+
+	LOGP(DLSMS, LOGL_DEBUG, "TX MT-forwardSM-Res\n");
+
+	/* Initialize a new GSUP message */
+	gsup_sm_msg_init(&gsup_msg, OSMO_GSUP_MSGT_MT_FORWARD_SM_RESULT,
+		trans->vsub->imsi, &sm_rp_mr);
+
+	return osmo_gsup_client_enc_send(trans->net->vlr->gsup_client, &gsup_msg);
+}
+
+int gsm411_gsup_mt_fwd_sm_err(struct gsm_trans *trans,
+	uint8_t sm_rp_mr, uint8_t cause)
+{
+	struct osmo_gsup_message gsup_msg;
+
+	/* Associate logging messages with this subscriber */
+	log_set_context(LOG_CTX_VLR_SUBSCR, trans->vsub);
+
+	LOGP(DLSMS, LOGL_DEBUG, "TX MT-forwardSM-Err\n");
+
+	/* Initialize a new GSUP message */
+	gsup_sm_msg_init(&gsup_msg, OSMO_GSUP_MSGT_MT_FORWARD_SM_ERROR,
+		trans->vsub->imsi, &sm_rp_mr);
+
+	/* SM-RP-Cause value */
+	gsup_msg.sm_rp_cause = &cause;
+
+	/* TODO: include optional SM-RP-UI field if present */
+	return osmo_gsup_client_enc_send(trans->net->vlr->gsup_client, &gsup_msg);
+}
+
+/* Handles MT SMS (and triggers Paging Request if required) */
+int gsm411_gsup_mt_handler(struct vlr_subscr *vsub,
+	struct osmo_gsup_message *gsup_msg)
+{
+	struct vlr_instance *vlr;
+	struct gsm_network *net;
+	int rc;
+
+	/* Obtain required pointers */
+	vlr = vsub->vlr;
+	net = (struct gsm_network *) vlr->user_ctx;
+
+	/* Associate logging messages with this subscriber */
+	log_set_context(LOG_CTX_VLR_SUBSCR, vsub);
+
+	LOGP(DLSMS, LOGL_DEBUG, "RX MT-forwardSM-Req\n");
+
+	/* Make sure that 'SMS over GSUP' is expected */
+	if (!net->sms_over_gsup) {
+		LOGP(DLSMS, LOGL_NOTICE, "Unexpected MT SMS over GSUP, "
+			"ignoring message...\n");
+		/* TODO: notify sender about that? */
+		return -EIO;
+	}
+
+	/**
+	 * Verify GSUP message
+	 *
+	 * FIXME: SM-RP-MR is not known yet (to be assigned by MSC)
+	 * NOTE: SM-RP-DA is out of our interest
+	 */
+	if (!gsup_msg->sm_rp_mr)
+		goto msg_error;
+	if (!gsup_msg->sm_rp_ui)
+		goto msg_error;
+
+	/* SM-RP-OA shall contain SMSC address */
+	if (gsup_msg->sm_rp_oa_type != OSMO_GSUP_SMS_SM_RP_ODA_SMSC_ADDR)
+		goto msg_error;
+
+	/* Send RP-DATA */
+	rc = gsm411_send_rp_data(net, vsub,
+		gsup_msg->sm_rp_oa_len, gsup_msg->sm_rp_oa,
+		gsup_msg->sm_rp_ui_len, gsup_msg->sm_rp_ui);
+	if (rc) {
+		LOGP(DLSMS, LOGL_NOTICE, "Failed to send MT SMS, "
+			"ignoring MT-forwardSM-Req message...\n");
+		/* TODO: notify sender about that? */
+		return rc;
+	}
+
+	return 0;
+
+msg_error:
+	/* TODO: notify sender about that? */
+	LOGP(DLSMS, LOGL_NOTICE, "RX malformed MT-forwardSM-Req\n");
+	return -EINVAL;
+}