cscn: some file moves/renames

1 files changed, 119 insertions, 0 deletions

diff --git a/openbsc/src/libmsc/iu_cs.c b/openbsc/src/libmsc/iu_cs.c
new file mode 100644
index 000000000..e321c15a1
--- /dev/null
+++ b/openbsc/src/libmsc/iu_cs.c
@@ -0,0 +1,119 @@
+#include <inttypes.h>
+
+#include <osmocom/core/logging.h>
+#include <openbsc/debug.h>
+
+#include <openbsc/gsm_data.h>
+#include <openbsc/iu.h>
+
+#include <openbsc/bsc_api.h> /* for BSC_API_CONN_POL_ACCEPT, TODO move that to libmsc */
+
+#include "../libmsc/msc_api.h"
+
+/* For A-interface see libbsc/bsc_api.c subscr_con_allocate() */
+struct gsm_subscriber_connection *subscr_conn_allocate_iu(struct gsm_network *network,
+							  struct ue_conn_ctx *ue)
+{
+	struct gsm_subscriber_connection *conn;
+
+	DEBUGP(DIUCS, "Allocating IuCS subscriber conn: link_id %p, conn_id %" PRIx32 "\n",
+	       ue->link, ue->conn_id);
+
+	conn = talloc_zero(network, struct gsm_subscriber_connection);
+	if (!conn)
+		return NULL;
+
+	conn->network = network;
+	conn->via_iface = IFACE_IUCS;
+	conn->iu.ue_ctx = ue;
+
+	llist_add_tail(&conn->entry, &network->subscr_conns);
+	return conn;
+}
+
+static int same_ue_conn(struct ue_conn_ctx *a, struct ue_conn_ctx *b)
+{
+	if (a == b)
+		return 1;
+	return (a->link == b->link)
+		&& (a->conn_id != b->conn_id);
+}
+
+/* Return an existing IuCS subscriber connection record for the given link and
+ * connection IDs, or return NULL if not found. */
+static struct gsm_subscriber_connection *subscr_conn_lookup_iu(struct gsm_network *network,
+							       struct ue_conn_ctx *ue)
+{
+	struct gsm_subscriber_connection *conn;
+
+	llist_for_each_entry(conn, &network->subscr_conns, entry) {
+		if (conn->via_iface != IFACE_IUCS)
+			continue;
+		if (!same_ue_conn(conn->iu.ue_ctx, ue))
+			continue;
+		DEBUGP(DIUCS, "Found IuCS subscriber for link_id %p, conn_id %" PRIx32 "\n",
+		       ue->link, ue->conn_id);
+		return conn;
+	}
+	DEBUGP(DIUCS, "No IuCS subscriber found for link_id %p, conn_id %" PRIx32 "\n",
+	       ue->link, ue->conn_id);
+	return NULL;
+}
+
+/* Receive MM/CC/... message from IuCS (SCCP user SAP).
+ * msg->dst must reference a struct ue_conn_ctx. link_id identifies the SCTP
+ * peer that sent the msg.
+ *
+ * For A-interface see libbsc/bsc_api.c gsm0408_rcvmsg(). */
+int gsm0408_rcvmsg_iucs(struct gsm_network *network, struct msgb *msg)
+{
+	int rc;
+	struct ue_conn_ctx *ue_ctx;
+	struct gsm_subscriber_connection *conn;
+
+	ue_ctx = (struct ue_conn_ctx*)msg->dst;
+
+	/* TODO: are there message types that could allow us to skip this
+	 * search? */
+	conn = subscr_conn_lookup_iu(network, ue_ctx);
+
+	if (conn) {
+		/* if we already have a connection, handle DTAP.
+		   gsm0408_dispatch() is aka msc_dtap() */
+
+		/* Make sure we don't receive RR over IuCS; otherwise all
+		 * messages handled by gsm0408_dispatch() are of interest (CC,
+		 * MM, SMS, NS_SS, maybe even MM_GPRS and SM_GPRS). */
+		struct gsm48_hdr *gh = msgb_l3(msg);
+		uint8_t pdisc = gh->proto_discr & 0x0f;
+		OSMO_ASSERT(pdisc != GSM48_PDISC_RR);
+
+		rc = gsm0408_dispatch(conn, msg);
+	} else {
+		/* allocate a new connection */
+
+		conn = subscr_conn_allocate_iu(network, ue_ctx);
+		if (!conn)
+			abort();
+
+		rc = msc_compl_l3(conn, msg, 0);
+		if (rc != BSC_API_CONN_POL_ACCEPT) {
+			subscr_con_free(conn);
+			rc = -1;
+		}
+		else
+			rc = 0;
+	}
+
+	return rc;
+}
+
+
+int iucs_submit_dtap(struct gsm_subscriber_connection *conn,
+		     struct msgb *msg)
+{
+	OSMO_ASSERT(conn->via_iface == IFACE_IUCS);
+	msg->dst = conn->iu.ue_ctx;
+	return iu_tx(msg, 0);
+}
+