Make extending subscriber creation easier

* rename variable controlling subscriber creation
* use enum for subscriber creation policy
* move check for subscriber creation policy into separate static
  function

Related: OS#1658, OS#1647
Change-Id: I3b10a9a764fd3a7bb96717a990e52caae16266da
Reviewed-on: https://gerrit.osmocom.org/42
Tested-by: Jenkins Builder
Reviewed-by: Holger Freyther <holger@freyther.de>

3 files changed, 17 insertions, 11 deletions

diff --git a/openbsc/src/libbsc/net_init.c b/openbsc/src/libbsc/net_init.c
index 568a0b85e..afcaaf33c 100644
--- a/openbsc/src/libbsc/net_init.c
+++ b/openbsc/src/libbsc/net_init.c
@@ -48,7 +48,7 @@ struct gsm_network *gsm_network_init(uint16_t country_code, uint16_t network_cod
 	INIT_LLIST_HEAD(&net->bsc_data->mscs);
 
 	net->subscr_group->net = net;
-	net->create_subscriber = 1;
+	net->subscr_creation_mode = GSM_SUBSCR_CREAT_W_RAND_EXT;
 
 	net->country_code = country_code;
 	net->network_code = network_code;
diff --git a/openbsc/src/libmsc/gsm_04_08.c b/openbsc/src/libmsc/gsm_04_08.c
index f02f784fe..0f00db151 100644
--- a/openbsc/src/libmsc/gsm_04_08.c
+++ b/openbsc/src/libmsc/gsm_04_08.c
@@ -507,6 +507,14 @@ static int mm_tx_identity_req(struct gsm_subscriber_connection *conn, uint8_t id
 	return gsm48_conn_sendmsg(msg, conn, NULL);
 }
 
+static struct gsm_subscriber *subscr_create(const struct gsm_network *net,
+					    const char *imsi)
+{
+	if (net->subscr_creation_mode != GSM_SUBSCR_DONT_CREATE)
+		return subscr_create_subscriber(net->subscr_group, imsi);
+
+	return NULL;
+}
 
 /* Parse Chapter 9.2.11 Identity Response */
 static int mm_rx_id_resp(struct gsm_subscriber_connection *conn, struct msgb *msg)
@@ -530,9 +538,8 @@ static int mm_rx_id_resp(struct gsm_subscriber_connection *conn, struct msgb *ms
 		if (!conn->subscr) {
 			conn->subscr = subscr_get_by_imsi(net->subscr_group,
 							  mi_string);
-			if (!conn->subscr && net->create_subscriber)
-				conn->subscr = subscr_create_subscriber(
-					net->subscr_group, mi_string);
+			if (!conn->subscr)
+				conn->subscr = subscr_create(net, mi_string);
 		}
 		if (!conn->subscr && conn->loc_operation) {
 			gsm0408_loc_upd_rej(conn, bts->network->reject_cause);
@@ -641,10 +648,9 @@ static int mm_rx_loc_upd_req(struct gsm_subscriber_connection *conn, struct msgb
 
 		/* look up subscriber based on IMSI, create if not found */
 		subscr = subscr_get_by_imsi(bts->network->subscr_group, mi_string);
-		if (!subscr && bts->network->create_subscriber) {
-			subscr = subscr_create_subscriber(
-				bts->network->subscr_group, mi_string);
-		}
+		if (!subscr)
+			subscr = subscr_create(bts->network, mi_string);
+
 		if (!subscr) {
 			gsm0408_loc_upd_rej(conn, bts->network->reject_cause);
 			release_loc_updating_req(conn, 0);
diff --git a/openbsc/src/libmsc/vty_interface_layer3.c b/openbsc/src/libmsc/vty_interface_layer3.c
index 4c2088a0f..5d74e04fa 100644
--- a/openbsc/src/libmsc/vty_interface_layer3.c
+++ b/openbsc/src/libmsc/vty_interface_layer3.c
@@ -1036,7 +1036,7 @@ DEFUN(cfg_nitb_subscr_create, cfg_nitb_subscr_create_cmd,
       "Make a new record when a subscriber is first seen.\n")
 {
 	struct gsm_network *gsmnet = gsmnet_from_vty(vty);
-	gsmnet->create_subscriber = 1;
+	gsmnet->subscr_creation_mode = GSM_SUBSCR_CREAT_W_RAND_EXT;
 	return CMD_SUCCESS;
 }
 
@@ -1045,7 +1045,7 @@ DEFUN(cfg_nitb_no_subscr_create, cfg_nitb_no_subscr_create_cmd,
       NO_STR "Make a new record when a subscriber is first seen.\n")
 {
 	struct gsm_network *gsmnet = gsmnet_from_vty(vty);
-	gsmnet->create_subscriber = 0;
+	gsmnet->subscr_creation_mode = GSM_SUBSCR_DONT_CREATE;
 	return CMD_SUCCESS;
 }
 
@@ -1072,7 +1072,7 @@ static int config_write_nitb(struct vty *vty)
 	struct gsm_network *gsmnet = gsmnet_from_vty(vty);
 	vty_out(vty, "nitb%s", VTY_NEWLINE);
 	vty_out(vty, " %ssubscriber-create-on-demand%s",
-		gsmnet->create_subscriber ? "" : "no ", VTY_NEWLINE);
+		gsmnet->subscr_creation_mode ? "" : "no ", VTY_NEWLINE);
 	vty_out(vty, " %sassign-tmsi%s",
 		gsmnet->avoid_tmsi ? "no " : "", VTY_NEWLINE);
 	return CMD_SUCCESS;