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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LAPB_H
#define _LAPB_H
#include <linux/lapb.h>
#include <linux/refcount.h>
#define LAPB_HEADER_LEN 20 /* LAPB over Ethernet + a bit more */
#define LAPB_ACK_PENDING_CONDITION 0x01
#define LAPB_REJECT_CONDITION 0x02
#define LAPB_PEER_RX_BUSY_CONDITION 0x04
/* Control field templates */
#define LAPB_I 0x00 /* Information frames */
#define LAPB_S 0x01 /* Supervisory frames */
#define LAPB_U 0x03 /* Unnumbered frames */
#define LAPB_RR 0x01 /* Receiver ready */
#define LAPB_RNR 0x05 /* Receiver not ready */
#define LAPB_REJ 0x09 /* Reject */
#define LAPB_SABM 0x2F /* Set Asynchronous Balanced Mode */
#define LAPB_SABME 0x6F /* Set Asynchronous Balanced Mode Extended */
#define LAPB_DISC 0x43 /* Disconnect */
#define LAPB_DM 0x0F /* Disconnected mode */
#define LAPB_UA 0x63 /* Unnumbered acknowledge */
#define LAPB_FRMR 0x87 /* Frame reject */
#define LAPB_ILLEGAL 0x100 /* Impossible to be a real frame type */
#define LAPB_SPF 0x10 /* Poll/final bit for standard LAPB */
#define LAPB_EPF 0x01 /* Poll/final bit for extended LAPB */
#define LAPB_FRMR_W 0x01 /* Control field invalid */
#define LAPB_FRMR_X 0x02 /* I field invalid */
#define LAPB_FRMR_Y 0x04 /* I field too long */
#define LAPB_FRMR_Z 0x08 /* Invalid N(R) */
#define LAPB_POLLOFF 0
#define LAPB_POLLON 1
/* LAPB C-bit */
#define LAPB_COMMAND 1
#define LAPB_RESPONSE 2
#define LAPB_ADDR_A 0x03
#define LAPB_ADDR_B 0x01
#define LAPB_ADDR_C 0x0F
#define LAPB_ADDR_D 0x07
/* Define Link State constants. */
enum {
LAPB_STATE_0, /* Disconnected State */
LAPB_STATE_1, /* Awaiting Connection State */
LAPB_STATE_2, /* Awaiting Disconnection State */
LAPB_STATE_3, /* Data Transfer State */
LAPB_STATE_4 /* Frame Reject State */
};
#define LAPB_DEFAULT_MODE (LAPB_STANDARD | LAPB_SLP | LAPB_DTE)
#define LAPB_DEFAULT_WINDOW 7 /* Window=7 */
#define LAPB_DEFAULT_T1 (5 * HZ) /* T1=5s */
#define LAPB_DEFAULT_T2 (1 * HZ) /* T2=1s */
#define LAPB_DEFAULT_N2 20 /* N2=20 */
#define LAPB_SMODULUS 8
#define LAPB_EMODULUS 128
/*
* Information about the current frame.
*/
struct lapb_frame {
unsigned short type; /* Parsed type */
unsigned short nr, ns; /* N(R), N(S) */
unsigned char cr; /* Command/Response */
unsigned char pf; /* Poll/Final */
unsigned char control[2]; /* Original control data*/
};
/*
* The per LAPB connection control structure.
*/
struct lapb_cb {
struct list_head node;
struct net_device *dev;
/* Link status fields */
unsigned int mode;
unsigned char state;
unsigned short vs, vr, va;
unsigned char condition;
unsigned short n2, n2count;
unsigned short t1, t2;
struct timer_list t1timer, t2timer;
bool t1timer_stop, t2timer_stop;
/* Internal control information */
struct sk_buff_head write_queue;
struct sk_buff_head ack_queue;
unsigned char window;
const struct lapb_register_struct *callbacks;
/* FRMR control information */
struct lapb_frame frmr_data;
unsigned char frmr_type;
spinlock_t lock;
refcount_t refcnt;
};
/* lapb_iface.c */
void lapb_connect_confirmation(struct lapb_cb *lapb, int);
void lapb_connect_indication(struct lapb_cb *lapb, int);
void lapb_disconnect_confirmation(struct lapb_cb *lapb, int);
void lapb_disconnect_indication(struct lapb_cb *lapb, int);
int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *);
int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *);
/* lapb_in.c */
void lapb_data_input(struct lapb_cb *lapb, struct sk_buff *);
/* lapb_out.c */
void lapb_kick(struct lapb_cb *lapb);
void lapb_transmit_buffer(struct lapb_cb *lapb, struct sk_buff *, int);
void lapb_establish_data_link(struct lapb_cb *lapb);
void lapb_enquiry_response(struct lapb_cb *lapb);
void lapb_timeout_response(struct lapb_cb *lapb);
void lapb_check_iframes_acked(struct lapb_cb *lapb, unsigned short);
void lapb_check_need_response(struct lapb_cb *lapb, int, int);
/* lapb_subr.c */
void lapb_clear_queues(struct lapb_cb *lapb);
void lapb_frames_acked(struct lapb_cb *lapb, unsigned short);
void lapb_requeue_frames(struct lapb_cb *lapb);
int lapb_validate_nr(struct lapb_cb *lapb, unsigned short);
int lapb_decode(struct lapb_cb *lapb, struct sk_buff *, struct lapb_frame *);
void lapb_send_control(struct lapb_cb *lapb, int, int, int);
void lapb_transmit_frmr(struct lapb_cb *lapb);
/* lapb_timer.c */
void lapb_start_t1timer(struct lapb_cb *lapb);
void lapb_start_t2timer(struct lapb_cb *lapb);
void lapb_stop_t1timer(struct lapb_cb *lapb);
void lapb_stop_t2timer(struct lapb_cb *lapb);
int lapb_t1timer_running(struct lapb_cb *lapb);
/*
* Debug levels.
* 0 = Off
* 1 = State Changes
* 2 = Packets I/O and State Changes
* 3 = Hex dumps, Packets I/O and State Changes.
*/
#define LAPB_DEBUG 0
#define lapb_dbg(level, fmt, ...) \
do { \
if (level < LAPB_DEBUG) \
pr_debug(fmt, ##__VA_ARGS__); \
} while (0)
#endif
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