xref: /linux/include/net/lapb.h (revision 182c2909e22d8a3ec39f8a4530fa19867cbd989b)
1 #ifndef _LAPB_H
2 #define _LAPB_H
3 #include <linux/lapb.h>
4 
5 #define	LAPB_HEADER_LEN	20		/* LAPB over Ethernet + a bit more */
6 
7 #define	LAPB_ACK_PENDING_CONDITION	0x01
8 #define	LAPB_REJECT_CONDITION		0x02
9 #define	LAPB_PEER_RX_BUSY_CONDITION	0x04
10 
11 /* Control field templates */
12 #define	LAPB_I		0x00	/* Information frames */
13 #define	LAPB_S		0x01	/* Supervisory frames */
14 #define	LAPB_U		0x03	/* Unnumbered frames */
15 
16 #define	LAPB_RR		0x01	/* Receiver ready */
17 #define	LAPB_RNR	0x05	/* Receiver not ready */
18 #define	LAPB_REJ	0x09	/* Reject */
19 
20 #define	LAPB_SABM	0x2F	/* Set Asynchronous Balanced Mode */
21 #define	LAPB_SABME	0x6F	/* Set Asynchronous Balanced Mode Extended */
22 #define	LAPB_DISC	0x43	/* Disconnect */
23 #define	LAPB_DM		0x0F	/* Disconnected mode */
24 #define	LAPB_UA		0x63	/* Unnumbered acknowledge */
25 #define	LAPB_FRMR	0x87	/* Frame reject */
26 
27 #define LAPB_ILLEGAL	0x100	/* Impossible to be a real frame type */
28 
29 #define	LAPB_SPF	0x10	/* Poll/final bit for standard LAPB */
30 #define	LAPB_EPF	0x01	/* Poll/final bit for extended LAPB */
31 
32 #define	LAPB_FRMR_W	0x01	/* Control field invalid	*/
33 #define	LAPB_FRMR_X	0x02	/* I field invalid		*/
34 #define	LAPB_FRMR_Y	0x04	/* I field too long		*/
35 #define	LAPB_FRMR_Z	0x08	/* Invalid N(R)			*/
36 
37 #define	LAPB_POLLOFF	0
38 #define	LAPB_POLLON	1
39 
40 /* LAPB C-bit */
41 #define LAPB_COMMAND	1
42 #define LAPB_RESPONSE	2
43 
44 #define	LAPB_ADDR_A	0x03
45 #define	LAPB_ADDR_B	0x01
46 #define	LAPB_ADDR_C	0x0F
47 #define	LAPB_ADDR_D	0x07
48 
49 /* Define Link State constants. */
50 enum {
51 	LAPB_STATE_0,	/* Disconnected State		*/
52 	LAPB_STATE_1,	/* Awaiting Connection State	*/
53 	LAPB_STATE_2,	/* Awaiting Disconnection State	*/
54 	LAPB_STATE_3,	/* Data Transfer State		*/
55 	LAPB_STATE_4	/* Frame Reject State		*/
56 };
57 
58 #define	LAPB_DEFAULT_MODE		(LAPB_STANDARD | LAPB_SLP | LAPB_DTE)
59 #define	LAPB_DEFAULT_WINDOW		7		/* Window=7 */
60 #define	LAPB_DEFAULT_T1			(5 * HZ)	/* T1=5s    */
61 #define	LAPB_DEFAULT_T2			(1 * HZ)	/* T2=1s    */
62 #define	LAPB_DEFAULT_N2			20		/* N2=20    */
63 
64 #define	LAPB_SMODULUS	8
65 #define	LAPB_EMODULUS	128
66 
67 /*
68  *	Information about the current frame.
69  */
70 struct lapb_frame {
71 	unsigned short		type;		/* Parsed type		*/
72 	unsigned short		nr, ns;		/* N(R), N(S)		*/
73 	unsigned char		cr;		/* Command/Response	*/
74 	unsigned char		pf;		/* Poll/Final		*/
75 	unsigned char		control[2];	/* Original control data*/
76 };
77 
78 /*
79  *	The per LAPB connection control structure.
80  */
81 struct lapb_cb {
82 	struct list_head	node;
83 	struct net_device	*dev;
84 
85 	/* Link status fields */
86 	unsigned int		mode;
87 	unsigned char		state;
88 	unsigned short		vs, vr, va;
89 	unsigned char		condition;
90 	unsigned short		n2, n2count;
91 	unsigned short		t1, t2;
92 	struct timer_list	t1timer, t2timer;
93 
94 	/* Internal control information */
95 	struct sk_buff_head	write_queue;
96 	struct sk_buff_head	ack_queue;
97 	unsigned char		window;
98 	const struct lapb_register_struct *callbacks;
99 
100 	/* FRMR control information */
101 	struct lapb_frame	frmr_data;
102 	unsigned char		frmr_type;
103 
104 	atomic_t		refcnt;
105 };
106 
107 /* lapb_iface.c */
108 void lapb_connect_confirmation(struct lapb_cb *lapb, int);
109 void lapb_connect_indication(struct lapb_cb *lapb, int);
110 void lapb_disconnect_confirmation(struct lapb_cb *lapb, int);
111 void lapb_disconnect_indication(struct lapb_cb *lapb, int);
112 int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *);
113 int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *);
114 
115 /* lapb_in.c */
116 void lapb_data_input(struct lapb_cb *lapb, struct sk_buff *);
117 
118 /* lapb_out.c */
119 void lapb_kick(struct lapb_cb *lapb);
120 void lapb_transmit_buffer(struct lapb_cb *lapb, struct sk_buff *, int);
121 void lapb_establish_data_link(struct lapb_cb *lapb);
122 void lapb_enquiry_response(struct lapb_cb *lapb);
123 void lapb_timeout_response(struct lapb_cb *lapb);
124 void lapb_check_iframes_acked(struct lapb_cb *lapb, unsigned short);
125 void lapb_check_need_response(struct lapb_cb *lapb, int, int);
126 
127 /* lapb_subr.c */
128 void lapb_clear_queues(struct lapb_cb *lapb);
129 void lapb_frames_acked(struct lapb_cb *lapb, unsigned short);
130 void lapb_requeue_frames(struct lapb_cb *lapb);
131 int lapb_validate_nr(struct lapb_cb *lapb, unsigned short);
132 int lapb_decode(struct lapb_cb *lapb, struct sk_buff *, struct lapb_frame *);
133 void lapb_send_control(struct lapb_cb *lapb, int, int, int);
134 void lapb_transmit_frmr(struct lapb_cb *lapb);
135 
136 /* lapb_timer.c */
137 void lapb_start_t1timer(struct lapb_cb *lapb);
138 void lapb_start_t2timer(struct lapb_cb *lapb);
139 void lapb_stop_t1timer(struct lapb_cb *lapb);
140 void lapb_stop_t2timer(struct lapb_cb *lapb);
141 int lapb_t1timer_running(struct lapb_cb *lapb);
142 
143 /*
144  * Debug levels.
145  *	0 = Off
146  *	1 = State Changes
147  *	2 = Packets I/O and State Changes
148  *	3 = Hex dumps, Packets I/O and State Changes.
149  */
150 #define	LAPB_DEBUG	0
151 
152 #define lapb_dbg(level, fmt, ...)			\
153 do {							\
154 	if (level < LAPB_DEBUG)				\
155 		pr_debug(fmt, ##__VA_ARGS__);		\
156 } while (0)
157 
158 #endif
159