libosmocore/include/osmocom/gprs/frame_relay.h

152 lines
4.5 KiB
C

/*! \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;
struct vty;
enum osmo_fr_role {
FR_ROLE_USER_EQUIPMENT,
FR_ROLE_NETWORK_EQUIPMENT,
};
/* 48.016 § 6.1.4.2 default maximum information field size of 1600 octets */
#define FRAME_RELAY_MTU 1600
/* FR DLC header is 2 byte */
#define FRAME_RELAY_SDU (FRAME_RELAY_MTU - 2)
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;
/* optional call-back to be called for each PDU received on an unknown DLC */
int (*unknown_dlc_rx_cb)(void *cb_data, struct msgb *msg);
void *unknown_dlc_rx_cb_data;
/* call-back to be called for transmitting on the underlying hardware */
int (*tx_cb)(void *data, struct msgb *msg);
/* optional call-back to be called each time the status changes active/inactive */
void (*status_cb)(struct osmo_fr_link *link, void *cb_data, bool active);
void *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 transferred to the USER;
* NET must wait until USER confirms it implicitly by a seq number check */
bool state_send;
/* call-back to be called for each PDU received on this DLC */
int (*rx_cb)(void *cb_data, struct msgb *msg);
/* optional call-back to be called each time the status changes active/inactive */
void (*status_cb)(struct osmo_fr_dlc *dlc, void *cb_data, bool active);
void *cb_data;
};
/* allocate a frame relay network */
struct osmo_fr_network *osmo_fr_network_alloc(void *ctx);
void osmo_fr_network_free(struct osmo_fr_network *net);
void osmo_fr_network_dump_vty(struct vty *vty, const struct osmo_fr_network *net);
/* 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);