ns2: add support for frame relay
Add support for frame relay over dahdi hdlc device.
It's supporting lmi by q933 and supports both
SGSN and BSS.
Change-Id: Id3b49f93d33c271f77cd9c9db03cde6b727a4d30
diff --git a/include/osmocom/gprs/frame_relay.h b/include/osmocom/gprs/frame_relay.h
new file mode 100644
index 0000000..b382ea8
--- /dev/null
+++ b/include/osmocom/gprs/frame_relay.h
@@ -0,0 +1,136 @@
+/*! \file frame_relay.h */
+
+/* (C) 2020 Harald Welte <laforge@gnumonks.org>
+ * (C) 2020 sysmocom - s.f.m.c. GmbH
+ * Author: Alexander Couzens <lynxis@fe80.eu>
+ *
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#pragma once
+
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/timer.h>
+#include <osmocom/core/utils.h>
+
+#include <stdint.h>
+
+struct osmo_tdef;
+struct msgb;
+
+enum osmo_fr_role {
+ FR_ROLE_USER_EQUIPMENT,
+ FR_ROLE_NETWORK_EQUIPMENT,
+};
+
+extern const struct value_string osmo_fr_role_names[];
+
+static inline const char *osmo_fr_role_str(enum osmo_fr_role role) {
+ return get_value_string(osmo_fr_role_names, role);
+}
+
+struct osmo_fr_network {
+ struct llist_head links;
+
+ unsigned int n391; /* full status polling counter */
+ unsigned int n392; /* error threshold */
+ unsigned int n393; /* monitored events count */
+
+ struct osmo_tdef *T_defs; /* T391, T392 */
+};
+
+struct osmo_fr_dlc;
+
+/* Frame Relay Link */
+struct osmo_fr_link {
+ /* list in osmo_fr_network.links */
+ struct llist_head list;
+ struct osmo_fr_network *net;
+ enum osmo_fr_role role;
+ /* human-readable name */
+ const char *name;
+
+ /* value of the last received send sequence number field in the
+ * link integrity verification information element */
+ uint8_t last_rx_seq;
+
+ /* value of the send sequence number field of the last link
+ * integrity verification information element sent */
+ uint8_t last_tx_seq;
+
+ struct osmo_timer_list t391;
+ struct osmo_timer_list t392;
+
+ unsigned int polling_count;
+ unsigned int err_count;
+ unsigned int succeed;
+ /* the type of the last status enquiry */
+ uint8_t expected_rep;
+ bool state;
+
+ /* list of data link connections at this link */
+ struct llist_head dlc_list;
+
+ int (*unknown_dlc_rx_cb)(void *cb_data, struct msgb *msg);
+ void *unknown_dlc_rx_cb_data;
+
+ int (*tx_cb)(void *data, struct msgb *msg);
+ void *tx_cb_data;
+};
+
+/* Frame Relay Data Link Connection */
+struct osmo_fr_dlc {
+ /* entry in fr_link.dlc_list */
+ struct llist_head list;
+ struct osmo_fr_link *link;
+
+ uint16_t dlci;
+
+ /* is this DLC marked active for traffic? */
+ bool active;
+ /* was this DLC newly added? */
+ bool add;
+ /* is this DLC about to be destroyed */
+ bool del;
+
+ /* the local state needs to be transfered to the
+ * UE. The NET must wait until the UE confirms it implicited by a seq number check */
+ bool state_send;
+
+ int (*rx_cb)(void *cb_data, struct msgb *msg);
+ void *rx_cb_data;
+};
+
+/* allocate a frame relay network */
+struct osmo_fr_network *osmo_fr_network_alloc(void *ctx);
+
+/* allocate a frame relay link in a given network */
+struct osmo_fr_link *osmo_fr_link_alloc(struct osmo_fr_network *net, enum osmo_fr_role role, const char *name);
+
+/* free a frame link in a given network */
+void osmo_fr_link_free(struct osmo_fr_link *link);
+
+/* allocate a data link connectoin on a given framerelay link */
+struct osmo_fr_dlc *osmo_fr_dlc_alloc(struct osmo_fr_link *link, uint16_t dlci);
+void osmo_fr_dlc_free(struct osmo_fr_dlc *dlc);
+
+struct osmo_fr_dlc *osmo_fr_dlc_by_dlci(struct osmo_fr_link *link, uint16_t dlci);
+
+int osmo_fr_rx(struct msgb *msg);
+int osmo_fr_tx_dlc(struct msgb *msg);