1 /*
2  *	Declarations of AX.25 type objects.
3  *
4  *	Alan Cox (GW4PTS) 	10/11/93
5  */
6 #ifndef _AX25_H
7 #define _AX25_H
8 
9 #include <linux/ax25.h>
10 #include <linux/spinlock.h>
11 #include <linux/timer.h>
12 #include <linux/list.h>
13 #include <linux/slab.h>
14 #include <linux/atomic.h>
15 
16 #define	AX25_T1CLAMPLO  		1
17 #define	AX25_T1CLAMPHI 			(30 * HZ)
18 
19 #define	AX25_BPQ_HEADER_LEN		16
20 #define	AX25_KISS_HEADER_LEN		1
21 
22 #define	AX25_HEADER_LEN			17
23 #define	AX25_ADDR_LEN			7
24 #define	AX25_DIGI_HEADER_LEN		(AX25_MAX_DIGIS * AX25_ADDR_LEN)
25 #define	AX25_MAX_HEADER_LEN		(AX25_HEADER_LEN + AX25_DIGI_HEADER_LEN)
26 
27 /* AX.25 Protocol IDs */
28 #define AX25_P_ROSE			0x01
29 #define AX25_P_VJCOMP			0x06	/* Compressed TCP/IP packet   */
30 						/* Van Jacobsen (RFC 1144)    */
31 #define AX25_P_VJUNCOMP			0x07	/* Uncompressed TCP/IP packet */
32 						/* Van Jacobsen (RFC 1144)    */
33 #define	AX25_P_SEGMENT			0x08	/* Segmentation fragment      */
34 #define AX25_P_TEXNET			0xc3	/* TEXTNET datagram protocol  */
35 #define AX25_P_LQ			0xc4	/* Link Quality Protocol      */
36 #define AX25_P_ATALK			0xca	/* Appletalk                  */
37 #define AX25_P_ATALK_ARP		0xcb	/* Appletalk ARP              */
38 #define AX25_P_IP			0xcc	/* ARPA Internet Protocol     */
39 #define AX25_P_ARP			0xcd	/* ARPA Address Resolution    */
40 #define AX25_P_FLEXNET			0xce	/* FlexNet                    */
41 #define AX25_P_NETROM 			0xcf	/* NET/ROM                    */
42 #define AX25_P_TEXT 			0xF0	/* No layer 3 protocol impl.  */
43 
44 /* AX.25 Segment control values */
45 #define	AX25_SEG_REM			0x7F
46 #define	AX25_SEG_FIRST			0x80
47 
48 #define AX25_CBIT			0x80	/* Command/Response bit */
49 #define AX25_EBIT			0x01	/* HDLC Address Extension bit */
50 #define AX25_HBIT			0x80	/* Has been repeated bit */
51 
52 #define AX25_SSSID_SPARE		0x60	/* Unused bits in SSID for standard AX.25 */
53 #define AX25_ESSID_SPARE		0x20	/* Unused bits in SSID for extended AX.25 */
54 #define AX25_DAMA_FLAG			0x20	/* Well, it is *NOT* unused! (dl1bke 951121 */
55 
56 #define	AX25_COND_ACK_PENDING		0x01
57 #define	AX25_COND_REJECT		0x02
58 #define	AX25_COND_PEER_RX_BUSY		0x04
59 #define	AX25_COND_OWN_RX_BUSY		0x08
60 #define	AX25_COND_DAMA_MODE		0x10
61 
62 #ifndef _LINUX_NETDEVICE_H
63 #include <linux/netdevice.h>
64 #endif
65 
66 /* Upper sub-layer (LAPB) definitions */
67 
68 /* Control field templates */
69 #define	AX25_I			0x00	/* Information frames */
70 #define	AX25_S			0x01	/* Supervisory frames */
71 #define	AX25_RR			0x01	/* Receiver ready */
72 #define	AX25_RNR		0x05	/* Receiver not ready */
73 #define	AX25_REJ		0x09	/* Reject */
74 #define	AX25_U			0x03	/* Unnumbered frames */
75 #define	AX25_SABM		0x2f	/* Set Asynchronous Balanced Mode */
76 #define	AX25_SABME		0x6f	/* Set Asynchronous Balanced Mode Extended */
77 #define	AX25_DISC		0x43	/* Disconnect */
78 #define	AX25_DM			0x0f	/* Disconnected mode */
79 #define	AX25_UA			0x63	/* Unnumbered acknowledge */
80 #define	AX25_FRMR		0x87	/* Frame reject */
81 #define	AX25_UI			0x03	/* Unnumbered information */
82 #define	AX25_XID		0xaf	/* Exchange information */
83 #define	AX25_TEST		0xe3	/* Test */
84 
85 #define	AX25_PF			0x10	/* Poll/final bit for standard AX.25 */
86 #define	AX25_EPF		0x01	/* Poll/final bit for extended AX.25 */
87 
88 #define AX25_ILLEGAL		0x100	/* Impossible to be a real frame type */
89 
90 #define	AX25_POLLOFF		0
91 #define	AX25_POLLON		1
92 
93 /* AX25 L2 C-bit */
94 #define AX25_COMMAND		1
95 #define AX25_RESPONSE		2
96 
97 /* Define Link State constants. */
98 
99 enum {
100 	AX25_STATE_0,			/* Listening */
101 	AX25_STATE_1,			/* SABM sent */
102 	AX25_STATE_2,			/* DISC sent */
103 	AX25_STATE_3,			/* Established */
104 	AX25_STATE_4			/* Recovery */
105 };
106 
107 #define AX25_MODULUS 		8	/*  Standard AX.25 modulus */
108 #define	AX25_EMODULUS		128	/*  Extended AX.25 modulus */
109 
110 enum {
111 	AX25_PROTO_STD_SIMPLEX,
112 	AX25_PROTO_STD_DUPLEX,
113 #ifdef CONFIG_AX25_DAMA_SLAVE
114 	AX25_PROTO_DAMA_SLAVE,
115 #ifdef CONFIG_AX25_DAMA_MASTER
116 	AX25_PROTO_DAMA_MASTER,
117 #define AX25_PROTO_MAX AX25_PROTO_DAMA_MASTER
118 #endif
119 #endif
120 	__AX25_PROTO_MAX,
121 	AX25_PROTO_MAX = __AX25_PROTO_MAX -1
122 };
123 
124 enum {
125 	AX25_VALUES_IPDEFMODE,	/* 0=DG 1=VC */
126 	AX25_VALUES_AXDEFMODE,	/* 0=Normal 1=Extended Seq Nos */
127 	AX25_VALUES_BACKOFF,	/* 0=None 1=Linear 2=Exponential */
128 	AX25_VALUES_CONMODE,	/* Allow connected modes - 0=No 1=no "PID text" 2=all PIDs */
129 	AX25_VALUES_WINDOW,	/* Default window size for standard AX.25 */
130 	AX25_VALUES_EWINDOW,	/* Default window size for extended AX.25 */
131 	AX25_VALUES_T1,		/* Default T1 timeout value */
132 	AX25_VALUES_T2,		/* Default T2 timeout value */
133 	AX25_VALUES_T3,		/* Default T3 timeout value */
134 	AX25_VALUES_IDLE,	/* Connected mode idle timer */
135 	AX25_VALUES_N2,		/* Default N2 value */
136 	AX25_VALUES_PACLEN,	/* AX.25 MTU */
137 	AX25_VALUES_PROTOCOL,	/* Std AX.25, DAMA Slave, DAMA Master */
138 	AX25_VALUES_DS_TIMEOUT,	/* DAMA Slave timeout */
139 	AX25_MAX_VALUES		/* THIS MUST REMAIN THE LAST ENTRY OF THIS LIST */
140 };
141 
142 #define	AX25_DEF_IPDEFMODE	0			/* Datagram */
143 #define	AX25_DEF_AXDEFMODE	0			/* Normal */
144 #define	AX25_DEF_BACKOFF	1			/* Linear backoff */
145 #define	AX25_DEF_CONMODE	2			/* Connected mode allowed */
146 #define	AX25_DEF_WINDOW		2			/* Window=2 */
147 #define	AX25_DEF_EWINDOW	32			/* Module-128 Window=32 */
148 #define	AX25_DEF_T1		10000			/* T1=10s */
149 #define	AX25_DEF_T2		3000			/* T2=3s  */
150 #define	AX25_DEF_T3		300000			/* T3=300s */
151 #define	AX25_DEF_N2		10			/* N2=10 */
152 #define AX25_DEF_IDLE		0			/* Idle=None */
153 #define AX25_DEF_PACLEN		256			/* Paclen=256 */
154 #define	AX25_DEF_PROTOCOL	AX25_PROTO_STD_SIMPLEX	/* Standard AX.25 */
155 #define AX25_DEF_DS_TIMEOUT	180000			/* DAMA timeout 3 minutes */
156 
157 typedef struct ax25_uid_assoc {
158 	struct hlist_node	uid_node;
159 	atomic_t		refcount;
160 	uid_t			uid;
161 	ax25_address		call;
162 } ax25_uid_assoc;
163 
164 #define ax25_uid_for_each(__ax25, node, list) \
165 	hlist_for_each_entry(__ax25, node, list, uid_node)
166 
167 #define ax25_uid_hold(ax25) \
168 	atomic_inc(&((ax25)->refcount))
169 
ax25_uid_put(ax25_uid_assoc * assoc)170 static inline void ax25_uid_put(ax25_uid_assoc *assoc)
171 {
172 	if (atomic_dec_and_test(&assoc->refcount)) {
173 		kfree(assoc);
174 	}
175 }
176 
177 typedef struct {
178 	ax25_address		calls[AX25_MAX_DIGIS];
179 	unsigned char		repeated[AX25_MAX_DIGIS];
180 	unsigned char		ndigi;
181 	signed char		lastrepeat;
182 } ax25_digi;
183 
184 typedef struct ax25_route {
185 	struct ax25_route	*next;
186 	atomic_t		refcount;
187 	ax25_address		callsign;
188 	struct net_device	*dev;
189 	ax25_digi		*digipeat;
190 	char			ip_mode;
191 } ax25_route;
192 
ax25_hold_route(ax25_route * ax25_rt)193 static inline void ax25_hold_route(ax25_route *ax25_rt)
194 {
195 	atomic_inc(&ax25_rt->refcount);
196 }
197 
198 extern void __ax25_put_route(ax25_route *ax25_rt);
199 
ax25_put_route(ax25_route * ax25_rt)200 static inline void ax25_put_route(ax25_route *ax25_rt)
201 {
202 	if (atomic_dec_and_test(&ax25_rt->refcount))
203 		__ax25_put_route(ax25_rt);
204 }
205 
206 typedef struct {
207 	char			slave;			/* slave_mode?   */
208 	struct timer_list	slave_timer;		/* timeout timer */
209 	unsigned short		slave_timeout;		/* when? */
210 } ax25_dama_info;
211 
212 struct ctl_table;
213 
214 typedef struct ax25_dev {
215 	struct ax25_dev		*next;
216 	struct net_device	*dev;
217 	struct net_device	*forward;
218 	struct ctl_table	*systable;
219 	int			values[AX25_MAX_VALUES];
220 #if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER)
221 	ax25_dama_info		dama;
222 #endif
223 } ax25_dev;
224 
225 typedef struct ax25_cb {
226 	struct hlist_node	ax25_node;
227 	ax25_address		source_addr, dest_addr;
228 	ax25_digi		*digipeat;
229 	ax25_dev		*ax25_dev;
230 	unsigned char		iamdigi;
231 	unsigned char		state, modulus, pidincl;
232 	unsigned short		vs, vr, va;
233 	unsigned char		condition, backoff;
234 	unsigned char		n2, n2count;
235 	struct timer_list	t1timer, t2timer, t3timer, idletimer;
236 	unsigned long		t1, t2, t3, idle, rtt;
237 	unsigned short		paclen, fragno, fraglen;
238 	struct sk_buff_head	write_queue;
239 	struct sk_buff_head	reseq_queue;
240 	struct sk_buff_head	ack_queue;
241 	struct sk_buff_head	frag_queue;
242 	unsigned char		window;
243 	struct timer_list	timer, dtimer;
244 	struct sock		*sk;		/* Backlink to socket */
245 	atomic_t		refcount;
246 } ax25_cb;
247 
248 #define ax25_sk(__sk) ((ax25_cb *)(__sk)->sk_protinfo)
249 
250 #define ax25_for_each(__ax25, node, list) \
251 	hlist_for_each_entry(__ax25, node, list, ax25_node)
252 
253 #define ax25_cb_hold(__ax25) \
254 	atomic_inc(&((__ax25)->refcount))
255 
ax25_cb_put(ax25_cb * ax25)256 static __inline__ void ax25_cb_put(ax25_cb *ax25)
257 {
258 	if (atomic_dec_and_test(&ax25->refcount)) {
259 		kfree(ax25->digipeat);
260 		kfree(ax25);
261 	}
262 }
263 
ax25_type_trans(struct sk_buff * skb,struct net_device * dev)264 static inline __be16 ax25_type_trans(struct sk_buff *skb, struct net_device *dev)
265 {
266 	skb->dev      = dev;
267 	skb_reset_mac_header(skb);
268 	skb->pkt_type = PACKET_HOST;
269 	return htons(ETH_P_AX25);
270 }
271 
272 /* af_ax25.c */
273 extern struct hlist_head ax25_list;
274 extern spinlock_t ax25_list_lock;
275 extern void ax25_cb_add(ax25_cb *);
276 struct sock *ax25_find_listener(ax25_address *, int, struct net_device *, int);
277 struct sock *ax25_get_socket(ax25_address *, ax25_address *, int);
278 extern ax25_cb *ax25_find_cb(ax25_address *, ax25_address *, ax25_digi *, struct net_device *);
279 extern void ax25_send_to_raw(ax25_address *, struct sk_buff *, int);
280 extern void ax25_destroy_socket(ax25_cb *);
281 extern ax25_cb * __must_check ax25_create_cb(void);
282 extern void ax25_fillin_cb(ax25_cb *, ax25_dev *);
283 extern struct sock *ax25_make_new(struct sock *, struct ax25_dev *);
284 
285 /* ax25_addr.c */
286 extern const ax25_address ax25_bcast;
287 extern const ax25_address ax25_defaddr;
288 extern const ax25_address null_ax25_address;
289 extern char *ax2asc(char *buf, const ax25_address *);
290 extern void asc2ax(ax25_address *addr, const char *callsign);
291 extern int ax25cmp(const ax25_address *, const ax25_address *);
292 extern int ax25digicmp(const ax25_digi *, const ax25_digi *);
293 extern const unsigned char *ax25_addr_parse(const unsigned char *, int,
294 	ax25_address *, ax25_address *, ax25_digi *, int *, int *);
295 extern int  ax25_addr_build(unsigned char *, const ax25_address *,
296 	const ax25_address *, const ax25_digi *, int, int);
297 extern int  ax25_addr_size(const ax25_digi *);
298 extern void ax25_digi_invert(const ax25_digi *, ax25_digi *);
299 
300 /* ax25_dev.c */
301 extern ax25_dev *ax25_dev_list;
302 extern spinlock_t ax25_dev_lock;
303 
ax25_dev_ax25dev(struct net_device * dev)304 static inline ax25_dev *ax25_dev_ax25dev(struct net_device *dev)
305 {
306 	return dev->ax25_ptr;
307 }
308 
309 extern ax25_dev *ax25_addr_ax25dev(ax25_address *);
310 extern void ax25_dev_device_up(struct net_device *);
311 extern void ax25_dev_device_down(struct net_device *);
312 extern int  ax25_fwd_ioctl(unsigned int, struct ax25_fwd_struct *);
313 extern struct net_device *ax25_fwd_dev(struct net_device *);
314 extern void ax25_dev_free(void);
315 
316 /* ax25_ds_in.c */
317 extern int  ax25_ds_frame_in(ax25_cb *, struct sk_buff *, int);
318 
319 /* ax25_ds_subr.c */
320 extern void ax25_ds_nr_error_recovery(ax25_cb *);
321 extern void ax25_ds_enquiry_response(ax25_cb *);
322 extern void ax25_ds_establish_data_link(ax25_cb *);
323 extern void ax25_dev_dama_off(ax25_dev *);
324 extern void ax25_dama_on(ax25_cb *);
325 extern void ax25_dama_off(ax25_cb *);
326 
327 /* ax25_ds_timer.c */
328 extern void ax25_ds_setup_timer(ax25_dev *);
329 extern void ax25_ds_set_timer(ax25_dev *);
330 extern void ax25_ds_del_timer(ax25_dev *);
331 extern void ax25_ds_timer(ax25_cb *);
332 extern void ax25_ds_t1_timeout(ax25_cb *);
333 extern void ax25_ds_heartbeat_expiry(ax25_cb *);
334 extern void ax25_ds_t3timer_expiry(ax25_cb *);
335 extern void ax25_ds_idletimer_expiry(ax25_cb *);
336 
337 /* ax25_iface.c */
338 
339 struct ax25_protocol {
340 	struct ax25_protocol *next;
341 	unsigned int pid;
342 	int (*func)(struct sk_buff *, ax25_cb *);
343 };
344 
345 extern void ax25_register_pid(struct ax25_protocol *ap);
346 extern void ax25_protocol_release(unsigned int);
347 
348 struct ax25_linkfail {
349 	struct hlist_node lf_node;
350 	void (*func)(ax25_cb *, int);
351 };
352 
353 extern void ax25_linkfail_register(struct ax25_linkfail *lf);
354 extern void ax25_linkfail_release(struct ax25_linkfail *lf);
355 extern int __must_check ax25_listen_register(ax25_address *,
356 	struct net_device *);
357 extern void ax25_listen_release(ax25_address *, struct net_device *);
358 extern int  (*ax25_protocol_function(unsigned int))(struct sk_buff *, ax25_cb *);
359 extern int  ax25_listen_mine(ax25_address *, struct net_device *);
360 extern void ax25_link_failed(ax25_cb *, int);
361 extern int  ax25_protocol_is_registered(unsigned int);
362 
363 /* ax25_in.c */
364 extern int  ax25_rx_iframe(ax25_cb *, struct sk_buff *);
365 extern int  ax25_kiss_rcv(struct sk_buff *, struct net_device *, struct packet_type *, struct net_device *);
366 
367 /* ax25_ip.c */
368 extern int ax25_hard_header(struct sk_buff *, struct net_device *,
369 			    unsigned short, const void *,
370 			    const void *, unsigned int);
371 extern int  ax25_rebuild_header(struct sk_buff *);
372 extern const struct header_ops ax25_header_ops;
373 
374 /* ax25_out.c */
375 extern ax25_cb *ax25_send_frame(struct sk_buff *, int, ax25_address *, ax25_address *, ax25_digi *, struct net_device *);
376 extern void ax25_output(ax25_cb *, int, struct sk_buff *);
377 extern void ax25_kick(ax25_cb *);
378 extern void ax25_transmit_buffer(ax25_cb *, struct sk_buff *, int);
379 extern void ax25_queue_xmit(struct sk_buff *skb, struct net_device *dev);
380 extern int  ax25_check_iframes_acked(ax25_cb *, unsigned short);
381 
382 /* ax25_route.c */
383 extern void ax25_rt_device_down(struct net_device *);
384 extern int  ax25_rt_ioctl(unsigned int, void __user *);
385 extern const struct file_operations ax25_route_fops;
386 extern ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev);
387 extern int  ax25_rt_autobind(ax25_cb *, ax25_address *);
388 extern struct sk_buff *ax25_rt_build_path(struct sk_buff *, ax25_address *, ax25_address *, ax25_digi *);
389 extern void ax25_rt_free(void);
390 
391 /* ax25_std_in.c */
392 extern int  ax25_std_frame_in(ax25_cb *, struct sk_buff *, int);
393 
394 /* ax25_std_subr.c */
395 extern void ax25_std_nr_error_recovery(ax25_cb *);
396 extern void ax25_std_establish_data_link(ax25_cb *);
397 extern void ax25_std_transmit_enquiry(ax25_cb *);
398 extern void ax25_std_enquiry_response(ax25_cb *);
399 extern void ax25_std_timeout_response(ax25_cb *);
400 
401 /* ax25_std_timer.c */
402 extern void ax25_std_heartbeat_expiry(ax25_cb *);
403 extern void ax25_std_t1timer_expiry(ax25_cb *);
404 extern void ax25_std_t2timer_expiry(ax25_cb *);
405 extern void ax25_std_t3timer_expiry(ax25_cb *);
406 extern void ax25_std_idletimer_expiry(ax25_cb *);
407 
408 /* ax25_subr.c */
409 extern void ax25_clear_queues(ax25_cb *);
410 extern void ax25_frames_acked(ax25_cb *, unsigned short);
411 extern void ax25_requeue_frames(ax25_cb *);
412 extern int  ax25_validate_nr(ax25_cb *, unsigned short);
413 extern int  ax25_decode(ax25_cb *, struct sk_buff *, int *, int *, int *);
414 extern void ax25_send_control(ax25_cb *, int, int, int);
415 extern void ax25_return_dm(struct net_device *, ax25_address *, ax25_address *, ax25_digi *);
416 extern void ax25_calculate_t1(ax25_cb *);
417 extern void ax25_calculate_rtt(ax25_cb *);
418 extern void ax25_disconnect(ax25_cb *, int);
419 
420 /* ax25_timer.c */
421 extern void ax25_setup_timers(ax25_cb *);
422 extern void ax25_start_heartbeat(ax25_cb *);
423 extern void ax25_start_t1timer(ax25_cb *);
424 extern void ax25_start_t2timer(ax25_cb *);
425 extern void ax25_start_t3timer(ax25_cb *);
426 extern void ax25_start_idletimer(ax25_cb *);
427 extern void ax25_stop_heartbeat(ax25_cb *);
428 extern void ax25_stop_t1timer(ax25_cb *);
429 extern void ax25_stop_t2timer(ax25_cb *);
430 extern void ax25_stop_t3timer(ax25_cb *);
431 extern void ax25_stop_idletimer(ax25_cb *);
432 extern int  ax25_t1timer_running(ax25_cb *);
433 extern unsigned long ax25_display_timer(struct timer_list *);
434 
435 /* ax25_uid.c */
436 extern int  ax25_uid_policy;
437 extern ax25_uid_assoc *ax25_findbyuid(uid_t);
438 extern int __must_check ax25_uid_ioctl(int, struct sockaddr_ax25 *);
439 extern const struct file_operations ax25_uid_fops;
440 extern void ax25_uid_free(void);
441 
442 /* sysctl_net_ax25.c */
443 #ifdef CONFIG_SYSCTL
444 extern void ax25_register_sysctl(void);
445 extern void ax25_unregister_sysctl(void);
446 #else
ax25_register_sysctl(void)447 static inline void ax25_register_sysctl(void) {};
ax25_unregister_sysctl(void)448 static inline void ax25_unregister_sysctl(void) {};
449 #endif /* CONFIG_SYSCTL */
450 
451 #endif
452