gsm48: Separate CM Service Reject sending and creation.

Split out the msg generation from the sending, this will
be used by the nat to send a refusal message.

3 files changed, 25 insertions, 9 deletions

diff --git a/openbsc/include/openbsc/gsm_04_08.h b/openbsc/include/openbsc/gsm_04_08.h
index 1d363d1e1..c5c1f91eb 100644
--- a/openbsc/include/openbsc/gsm_04_08.h
+++ b/openbsc/include/openbsc/gsm_04_08.h
@@ -53,5 +53,6 @@ int gsm48_lchan_modify(struct gsm_lchan *lchan, u_int8_t lchan_mode);
 int gsm48_rx_rr_modif_ack(struct msgb *msg);
 int gsm48_parse_meas_rep(struct gsm_meas_rep *rep, struct msgb *msg);
 
+struct msgb *gsm48_create_mm_serv_rej(enum gsm48_reject_value value);
 
 #endif
diff --git a/openbsc/src/gsm_04_08.c b/openbsc/src/gsm_04_08.c
index c98643883..005ee1cae 100644
--- a/openbsc/src/gsm_04_08.c
+++ b/openbsc/src/gsm_04_08.c
@@ -574,19 +574,17 @@ static int gsm48_tx_mm_serv_ack(struct gsm_lchan *lchan)
 static int gsm48_tx_mm_serv_rej(struct gsm_subscriber_connection *conn,
 				enum gsm48_reject_value value)
 {
-	struct msgb *msg = gsm48_msgb_alloc();
-	struct gsm48_hdr *gh;
+	struct msgb *msg;
 
-	gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
+	msg = gsm48_create_mm_serv_rej(value);
+	if (!msg) {
+		LOGP(DMM, LOGL_ERROR, "Failed to allocate CM Service Reject.\n");
+		return -1;
+	}
 
+	DEBUGP(DMM, "-> CM SERVICE Reject cause: %d\n", value);
 	msg->lchan = conn->lchan;
 	use_subscr_con(conn);
-
-	gh->proto_discr = GSM48_PDISC_MM;
-	gh->msg_type = GSM48_MT_MM_CM_SERV_REJ;
-	gh->data[0] = value;
-	DEBUGP(DMM, "-> CM SERVICE Reject cause: %d\n", value);
-
 	return gsm48_sendmsg(msg, NULL);
 }
 
diff --git a/openbsc/src/gsm_04_08_utils.c b/openbsc/src/gsm_04_08_utils.c
index c54bdd310..af100f799 100644
--- a/openbsc/src/gsm_04_08_utils.c
+++ b/openbsc/src/gsm_04_08_utils.c
@@ -629,3 +629,20 @@ int gsm48_parse_meas_rep(struct gsm_meas_rep *rep, struct msgb *msg)
 
 	return 0;
 }
+
+struct msgb *gsm48_create_mm_serv_rej(enum gsm48_reject_value value)
+{
+	struct msgb *msg;
+	struct gsm48_hdr *gh;
+
+	msg = gsm48_msgb_alloc();
+	if (!msg)
+		return NULL;
+
+	gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
+	gh->proto_discr = GSM48_PDISC_MM;
+	gh->msg_type = GSM48_MT_MM_CM_SERV_REJ;
+	gh->data[0] = value;
+
+	return msg;
+}