1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LAPB_H
3#define _LAPB_H
4#include <linux/lapb.h>
5#include <linux/refcount.h>
6
7#define LAPB_HEADER_LEN 20 /* LAPB over Ethernet + a bit more */
8
9#define LAPB_ACK_PENDING_CONDITION 0x01
10#define LAPB_REJECT_CONDITION 0x02
11#define LAPB_PEER_RX_BUSY_CONDITION 0x04
12
13/* Control field templates */
14#define LAPB_I 0x00 /* Information frames */
15#define LAPB_S 0x01 /* Supervisory frames */
16#define LAPB_U 0x03 /* Unnumbered frames */
17
18#define LAPB_RR 0x01 /* Receiver ready */
19#define LAPB_RNR 0x05 /* Receiver not ready */
20#define LAPB_REJ 0x09 /* Reject */
21
22#define LAPB_SABM 0x2F /* Set Asynchronous Balanced Mode */
23#define LAPB_SABME 0x6F /* Set Asynchronous Balanced Mode Extended */
24#define LAPB_DISC 0x43 /* Disconnect */
25#define LAPB_DM 0x0F /* Disconnected mode */
26#define LAPB_UA 0x63 /* Unnumbered acknowledge */
27#define LAPB_FRMR 0x87 /* Frame reject */
28
29#define LAPB_ILLEGAL 0x100 /* Impossible to be a real frame type */
30
31#define LAPB_SPF 0x10 /* Poll/final bit for standard LAPB */
32#define LAPB_EPF 0x01 /* Poll/final bit for extended LAPB */
33
34#define LAPB_FRMR_W 0x01 /* Control field invalid */
35#define LAPB_FRMR_X 0x02 /* I field invalid */
36#define LAPB_FRMR_Y 0x04 /* I field too long */
37#define LAPB_FRMR_Z 0x08 /* Invalid N(R) */
38
39#define LAPB_POLLOFF 0
40#define LAPB_POLLON 1
41
42/* LAPB C-bit */
43#define LAPB_COMMAND 1
44#define LAPB_RESPONSE 2
45
46#define LAPB_ADDR_A 0x03
47#define LAPB_ADDR_B 0x01
48#define LAPB_ADDR_C 0x0F
49#define LAPB_ADDR_D 0x07
50
51/* Define Link State constants. */
52enum {
53 LAPB_STATE_0, /* Disconnected State */
54 LAPB_STATE_1, /* Awaiting Connection State */
55 LAPB_STATE_2, /* Awaiting Disconnection State */
56 LAPB_STATE_3, /* Data Transfer State */
57 LAPB_STATE_4 /* Frame Reject State */
58};
59
60#define LAPB_DEFAULT_MODE (LAPB_STANDARD | LAPB_SLP | LAPB_DTE)
61#define LAPB_DEFAULT_WINDOW 7 /* Window=7 */
62#define LAPB_DEFAULT_T1 (5 * HZ) /* T1=5s */
63#define LAPB_DEFAULT_T2 (1 * HZ) /* T2=1s */
64#define LAPB_DEFAULT_N2 20 /* N2=20 */
65
66#define LAPB_SMODULUS 8
67#define LAPB_EMODULUS 128
68
69/*
70 * Information about the current frame.
71 */
72struct lapb_frame {
73 unsigned short type; /* Parsed type */
74 unsigned short nr, ns; /* N(R), N(S) */
75 unsigned char cr; /* Command/Response */
76 unsigned char pf; /* Poll/Final */
77 unsigned char control[2]; /* Original control data*/
78};
79
80/*
81 * The per LAPB connection control structure.
82 */
83struct lapb_cb {
84 struct list_head node;
85 struct net_device *dev;
86
87 /* Link status fields */
88 unsigned int mode;
89 unsigned char state;
90 unsigned short vs, vr, va;
91 unsigned char condition;
92 unsigned short n2, n2count;
93 unsigned short t1, t2;
94 struct timer_list t1timer, t2timer;
95
96 /* Internal control information */
97 struct sk_buff_head write_queue;
98 struct sk_buff_head ack_queue;
99 unsigned char window;
100 const struct lapb_register_struct *callbacks;
101
102 /* FRMR control information */
103 struct lapb_frame frmr_data;
104 unsigned char frmr_type;
105
106 refcount_t refcnt;
107};
108
109/* lapb_iface.c */
110void lapb_connect_confirmation(struct lapb_cb *lapb, int);
111void lapb_connect_indication(struct lapb_cb *lapb, int);
112void lapb_disconnect_confirmation(struct lapb_cb *lapb, int);
113void lapb_disconnect_indication(struct lapb_cb *lapb, int);
114int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *);
115int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *);
116
117/* lapb_in.c */
118void lapb_data_input(struct lapb_cb *lapb, struct sk_buff *);
119
120/* lapb_out.c */
121void lapb_kick(struct lapb_cb *lapb);
122void lapb_transmit_buffer(struct lapb_cb *lapb, struct sk_buff *, int);
123void lapb_establish_data_link(struct lapb_cb *lapb);
124void lapb_enquiry_response(struct lapb_cb *lapb);
125void lapb_timeout_response(struct lapb_cb *lapb);
126void lapb_check_iframes_acked(struct lapb_cb *lapb, unsigned short);
127void lapb_check_need_response(struct lapb_cb *lapb, int, int);
128
129/* lapb_subr.c */
130void lapb_clear_queues(struct lapb_cb *lapb);
131void lapb_frames_acked(struct lapb_cb *lapb, unsigned short);
132void lapb_requeue_frames(struct lapb_cb *lapb);
133int lapb_validate_nr(struct lapb_cb *lapb, unsigned short);
134int lapb_decode(struct lapb_cb *lapb, struct sk_buff *, struct lapb_frame *);
135void lapb_send_control(struct lapb_cb *lapb, int, int, int);
136void lapb_transmit_frmr(struct lapb_cb *lapb);
137
138/* lapb_timer.c */
139void lapb_start_t1timer(struct lapb_cb *lapb);
140void lapb_start_t2timer(struct lapb_cb *lapb);
141void lapb_stop_t1timer(struct lapb_cb *lapb);
142void lapb_stop_t2timer(struct lapb_cb *lapb);
143int lapb_t1timer_running(struct lapb_cb *lapb);
144
145/*
146 * Debug levels.
147 * 0 = Off
148 * 1 = State Changes
149 * 2 = Packets I/O and State Changes
150 * 3 = Hex dumps, Packets I/O and State Changes.
151 */
152#define LAPB_DEBUG 0
153
154#define lapb_dbg(level, fmt, ...) \
155do { \
156 if (level < LAPB_DEBUG) \
157 pr_debug(fmt, ##__VA_ARGS__); \
158} while (0)
159
160#endif
161