1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Declarations of AX.25 type objects.
4 *
5 * Alan Cox (GW4PTS) 10/11/93
6 */
7 #ifndef _AX25_H
8 #define _AX25_H
9
10 #include <linux/ax25.h>
11 #include <linux/spinlock.h>
12 #include <linux/timer.h>
13 #include <linux/list.h>
14 #include <linux/slab.h>
15 #include <linux/refcount.h>
16 #include <net/neighbour.h>
17 #include <net/sock.h>
18 #include <linux/seq_file.h>
19
20 #define AX25_T1CLAMPLO 1
21 #define AX25_T1CLAMPHI (30 * HZ)
22
23 #define AX25_BPQ_HEADER_LEN 16
24 #define AX25_KISS_HEADER_LEN 1
25
26 #define AX25_HEADER_LEN 17
27 #define AX25_ADDR_LEN 7
28 #define AX25_DIGI_HEADER_LEN (AX25_MAX_DIGIS * AX25_ADDR_LEN)
29 #define AX25_MAX_HEADER_LEN (AX25_HEADER_LEN + AX25_DIGI_HEADER_LEN)
30
31 /* AX.25 Protocol IDs */
32 #define AX25_P_ROSE 0x01
33 #define AX25_P_VJCOMP 0x06 /* Compressed TCP/IP packet */
34 /* Van Jacobsen (RFC 1144) */
35 #define AX25_P_VJUNCOMP 0x07 /* Uncompressed TCP/IP packet */
36 /* Van Jacobsen (RFC 1144) */
37 #define AX25_P_SEGMENT 0x08 /* Segmentation fragment */
38 #define AX25_P_TEXNET 0xc3 /* TEXTNET datagram protocol */
39 #define AX25_P_LQ 0xc4 /* Link Quality Protocol */
40 #define AX25_P_ATALK 0xca /* Appletalk */
41 #define AX25_P_ATALK_ARP 0xcb /* Appletalk ARP */
42 #define AX25_P_IP 0xcc /* ARPA Internet Protocol */
43 #define AX25_P_ARP 0xcd /* ARPA Address Resolution */
44 #define AX25_P_FLEXNET 0xce /* FlexNet */
45 #define AX25_P_NETROM 0xcf /* NET/ROM */
46 #define AX25_P_TEXT 0xF0 /* No layer 3 protocol impl. */
47
48 /* AX.25 Segment control values */
49 #define AX25_SEG_REM 0x7F
50 #define AX25_SEG_FIRST 0x80
51
52 #define AX25_CBIT 0x80 /* Command/Response bit */
53 #define AX25_EBIT 0x01 /* HDLC Address Extension bit */
54 #define AX25_HBIT 0x80 /* Has been repeated bit */
55
56 #define AX25_SSSID_SPARE 0x60 /* Unused bits in SSID for standard AX.25 */
57 #define AX25_ESSID_SPARE 0x20 /* Unused bits in SSID for extended AX.25 */
58 #define AX25_DAMA_FLAG 0x20 /* Well, it is *NOT* unused! (dl1bke 951121 */
59
60 #define AX25_COND_ACK_PENDING 0x01
61 #define AX25_COND_REJECT 0x02
62 #define AX25_COND_PEER_RX_BUSY 0x04
63 #define AX25_COND_OWN_RX_BUSY 0x08
64 #define AX25_COND_DAMA_MODE 0x10
65
66 #ifndef _LINUX_NETDEVICE_H
67 #include <linux/netdevice.h>
68 #endif
69
70 /* Upper sub-layer (LAPB) definitions */
71
72 /* Control field templates */
73 #define AX25_I 0x00 /* Information frames */
74 #define AX25_S 0x01 /* Supervisory frames */
75 #define AX25_RR 0x01 /* Receiver ready */
76 #define AX25_RNR 0x05 /* Receiver not ready */
77 #define AX25_REJ 0x09 /* Reject */
78 #define AX25_U 0x03 /* Unnumbered frames */
79 #define AX25_SABM 0x2f /* Set Asynchronous Balanced Mode */
80 #define AX25_SABME 0x6f /* Set Asynchronous Balanced Mode Extended */
81 #define AX25_DISC 0x43 /* Disconnect */
82 #define AX25_DM 0x0f /* Disconnected mode */
83 #define AX25_UA 0x63 /* Unnumbered acknowledge */
84 #define AX25_FRMR 0x87 /* Frame reject */
85 #define AX25_UI 0x03 /* Unnumbered information */
86 #define AX25_XID 0xaf /* Exchange information */
87 #define AX25_TEST 0xe3 /* Test */
88
89 #define AX25_PF 0x10 /* Poll/final bit for standard AX.25 */
90 #define AX25_EPF 0x01 /* Poll/final bit for extended AX.25 */
91
92 #define AX25_ILLEGAL 0x100 /* Impossible to be a real frame type */
93
94 #define AX25_POLLOFF 0
95 #define AX25_POLLON 1
96
97 /* AX25 L2 C-bit */
98 #define AX25_COMMAND 1
99 #define AX25_RESPONSE 2
100
101 /* Define Link State constants. */
102
103 enum {
104 AX25_STATE_0, /* Listening */
105 AX25_STATE_1, /* SABM sent */
106 AX25_STATE_2, /* DISC sent */
107 AX25_STATE_3, /* Established */
108 AX25_STATE_4 /* Recovery */
109 };
110
111 #define AX25_MODULUS 8 /* Standard AX.25 modulus */
112 #define AX25_EMODULUS 128 /* Extended AX.25 modulus */
113
114 enum {
115 AX25_PROTO_STD_SIMPLEX,
116 AX25_PROTO_STD_DUPLEX,
117 #ifdef CONFIG_AX25_DAMA_SLAVE
118 AX25_PROTO_DAMA_SLAVE,
119 #ifdef CONFIG_AX25_DAMA_MASTER
120 AX25_PROTO_DAMA_MASTER,
121 #define AX25_PROTO_MAX AX25_PROTO_DAMA_MASTER
122 #endif
123 #endif
124 __AX25_PROTO_MAX,
125 AX25_PROTO_MAX = __AX25_PROTO_MAX -1
126 };
127
128 enum {
129 AX25_VALUES_IPDEFMODE, /* 0=DG 1=VC */
130 AX25_VALUES_AXDEFMODE, /* 0=Normal 1=Extended Seq Nos */
131 AX25_VALUES_BACKOFF, /* 0=None 1=Linear 2=Exponential */
132 AX25_VALUES_CONMODE, /* Allow connected modes - 0=No 1=no "PID text" 2=all PIDs */
133 AX25_VALUES_WINDOW, /* Default window size for standard AX.25 */
134 AX25_VALUES_EWINDOW, /* Default window size for extended AX.25 */
135 AX25_VALUES_T1, /* Default T1 timeout value */
136 AX25_VALUES_T2, /* Default T2 timeout value */
137 AX25_VALUES_T3, /* Default T3 timeout value */
138 AX25_VALUES_IDLE, /* Connected mode idle timer */
139 AX25_VALUES_N2, /* Default N2 value */
140 AX25_VALUES_PACLEN, /* AX.25 MTU */
141 AX25_VALUES_PROTOCOL, /* Std AX.25, DAMA Slave, DAMA Master */
142 AX25_VALUES_DS_TIMEOUT, /* DAMA Slave timeout */
143 AX25_MAX_VALUES /* THIS MUST REMAIN THE LAST ENTRY OF THIS LIST */
144 };
145
146 #define AX25_DEF_IPDEFMODE 0 /* Datagram */
147 #define AX25_DEF_AXDEFMODE 0 /* Normal */
148 #define AX25_DEF_BACKOFF 1 /* Linear backoff */
149 #define AX25_DEF_CONMODE 2 /* Connected mode allowed */
150 #define AX25_DEF_WINDOW 2 /* Window=2 */
151 #define AX25_DEF_EWINDOW 32 /* Module-128 Window=32 */
152 #define AX25_DEF_T1 10000 /* T1=10s */
153 #define AX25_DEF_T2 3000 /* T2=3s */
154 #define AX25_DEF_T3 300000 /* T3=300s */
155 #define AX25_DEF_N2 10 /* N2=10 */
156 #define AX25_DEF_IDLE 0 /* Idle=None */
157 #define AX25_DEF_PACLEN 256 /* Paclen=256 */
158 #define AX25_DEF_PROTOCOL AX25_PROTO_STD_SIMPLEX /* Standard AX.25 */
159 #define AX25_DEF_DS_TIMEOUT 180000 /* DAMA timeout 3 minutes */
160
161 typedef struct ax25_uid_assoc {
162 struct hlist_node uid_node;
163 refcount_t refcount;
164 kuid_t uid;
165 ax25_address call;
166 } ax25_uid_assoc;
167
168 #define ax25_uid_for_each(__ax25, list) \
169 hlist_for_each_entry(__ax25, list, uid_node)
170
171 #define ax25_uid_hold(ax25) \
172 refcount_inc(&((ax25)->refcount))
173
ax25_uid_put(ax25_uid_assoc * assoc)174 static inline void ax25_uid_put(ax25_uid_assoc *assoc)
175 {
176 if (refcount_dec_and_test(&assoc->refcount)) {
177 kfree(assoc);
178 }
179 }
180
181 typedef struct {
182 ax25_address calls[AX25_MAX_DIGIS];
183 unsigned char repeated[AX25_MAX_DIGIS];
184 unsigned char ndigi;
185 signed char lastrepeat;
186 } ax25_digi;
187
188 typedef struct ax25_route {
189 struct ax25_route *next;
190 ax25_address callsign;
191 struct net_device *dev;
192 ax25_digi *digipeat;
193 char ip_mode;
194 } ax25_route;
195
196 void __ax25_put_route(ax25_route *ax25_rt);
197
198 extern rwlock_t ax25_route_lock;
199
ax25_route_lock_use(void)200 static inline void ax25_route_lock_use(void)
201 {
202 read_lock(&ax25_route_lock);
203 }
204
ax25_route_lock_unuse(void)205 static inline void ax25_route_lock_unuse(void)
206 {
207 read_unlock(&ax25_route_lock);
208 }
209
210 typedef struct {
211 char slave; /* slave_mode? */
212 struct timer_list slave_timer; /* timeout timer */
213 unsigned short slave_timeout; /* when? */
214 } ax25_dama_info;
215
216 struct ctl_table;
217
218 typedef struct ax25_dev {
219 struct list_head list;
220
221 struct net_device *dev;
222 netdevice_tracker dev_tracker;
223
224 struct net_device *forward;
225 struct ctl_table_header *sysheader;
226 int values[AX25_MAX_VALUES];
227 #if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER)
228 ax25_dama_info dama;
229 #endif
230 refcount_t refcount;
231 bool device_up;
232 } ax25_dev;
233
234 typedef struct ax25_cb {
235 struct hlist_node ax25_node;
236 ax25_address source_addr, dest_addr;
237 ax25_digi *digipeat;
238 ax25_dev *ax25_dev;
239 netdevice_tracker dev_tracker;
240 unsigned char iamdigi;
241 unsigned char state, modulus, pidincl;
242 unsigned short vs, vr, va;
243 unsigned char condition, backoff;
244 unsigned char n2, n2count;
245 struct timer_list t1timer, t2timer, t3timer, idletimer;
246 unsigned long t1, t2, t3, idle, rtt;
247 unsigned short paclen, fragno, fraglen;
248 struct sk_buff_head write_queue;
249 struct sk_buff_head reseq_queue;
250 struct sk_buff_head ack_queue;
251 struct sk_buff_head frag_queue;
252 unsigned char window;
253 struct timer_list timer, dtimer;
254 struct sock *sk; /* Backlink to socket */
255 refcount_t refcount;
256 } ax25_cb;
257
258 struct ax25_sock {
259 struct sock sk;
260 struct ax25_cb *cb;
261 };
262
263 #define ax25_sk(ptr) container_of_const(ptr, struct ax25_sock, sk)
264
sk_to_ax25(const struct sock * sk)265 static inline struct ax25_cb *sk_to_ax25(const struct sock *sk)
266 {
267 return ax25_sk(sk)->cb;
268 }
269
270 #define ax25_for_each(__ax25, list) \
271 hlist_for_each_entry(__ax25, list, ax25_node)
272
273 #define ax25_cb_hold(__ax25) \
274 refcount_inc(&((__ax25)->refcount))
275
ax25_cb_put(ax25_cb * ax25)276 static __inline__ void ax25_cb_put(ax25_cb *ax25)
277 {
278 if (refcount_dec_and_test(&ax25->refcount)) {
279 kfree(ax25->digipeat);
280 kfree(ax25);
281 }
282 }
283
ax25_dev_hold(ax25_dev * ax25_dev)284 static inline void ax25_dev_hold(ax25_dev *ax25_dev)
285 {
286 refcount_inc(&ax25_dev->refcount);
287 }
288
ax25_dev_put(ax25_dev * ax25_dev)289 static inline void ax25_dev_put(ax25_dev *ax25_dev)
290 {
291 if (refcount_dec_and_test(&ax25_dev->refcount)) {
292 kfree(ax25_dev);
293 }
294 }
ax25_type_trans(struct sk_buff * skb,struct net_device * dev)295 static inline __be16 ax25_type_trans(struct sk_buff *skb, struct net_device *dev)
296 {
297 skb->dev = dev;
298 skb_reset_mac_header(skb);
299 skb->pkt_type = PACKET_HOST;
300 return htons(ETH_P_AX25);
301 }
302
303 /* af_ax25.c */
304 extern struct hlist_head ax25_list;
305 extern spinlock_t ax25_list_lock;
306 void ax25_cb_add(ax25_cb *);
307 struct sock *ax25_find_listener(ax25_address *, int, struct net_device *, int);
308 struct sock *ax25_get_socket(ax25_address *, ax25_address *, int);
309 ax25_cb *ax25_find_cb(const ax25_address *, ax25_address *, ax25_digi *,
310 struct net_device *);
311 void ax25_send_to_raw(ax25_address *, struct sk_buff *, int);
312 void ax25_destroy_socket(ax25_cb *);
313 ax25_cb * __must_check ax25_create_cb(void);
314 void ax25_fillin_cb(ax25_cb *, ax25_dev *);
315 struct sock *ax25_make_new(struct sock *, struct ax25_dev *);
316
317 /* ax25_addr.c */
318 extern const ax25_address ax25_bcast;
319 extern const ax25_address ax25_defaddr;
320 extern const ax25_address null_ax25_address;
321 char *ax2asc(char *buf, const ax25_address *);
322 void asc2ax(ax25_address *addr, const char *callsign);
323 int ax25cmp(const ax25_address *, const ax25_address *);
324 int ax25digicmp(const ax25_digi *, const ax25_digi *);
325 const unsigned char *ax25_addr_parse(const unsigned char *, int,
326 ax25_address *, ax25_address *, ax25_digi *, int *, int *);
327 int ax25_addr_build(unsigned char *, const ax25_address *,
328 const ax25_address *, const ax25_digi *, int, int);
329 int ax25_addr_size(const ax25_digi *);
330 void ax25_digi_invert(const ax25_digi *, ax25_digi *);
331
332 /* ax25_dev.c */
333 extern spinlock_t ax25_dev_lock;
334
335 #if IS_ENABLED(CONFIG_AX25)
ax25_dev_ax25dev(struct net_device * dev)336 static inline ax25_dev *ax25_dev_ax25dev(struct net_device *dev)
337 {
338 return dev->ax25_ptr;
339 }
340 #endif
341
342 ax25_dev *ax25_addr_ax25dev(ax25_address *);
343 void ax25_dev_device_up(struct net_device *);
344 void ax25_dev_device_down(struct net_device *);
345 int ax25_fwd_ioctl(unsigned int, struct ax25_fwd_struct *);
346 struct net_device *ax25_fwd_dev(struct net_device *);
347 void ax25_dev_free(void);
348
349 /* ax25_ds_in.c */
350 int ax25_ds_frame_in(ax25_cb *, struct sk_buff *, int);
351
352 /* ax25_ds_subr.c */
353 void ax25_ds_nr_error_recovery(ax25_cb *);
354 void ax25_ds_enquiry_response(ax25_cb *);
355 void ax25_ds_establish_data_link(ax25_cb *);
356 void ax25_dev_dama_off(ax25_dev *);
357 void ax25_dama_on(ax25_cb *);
358 void ax25_dama_off(ax25_cb *);
359
360 /* ax25_ds_timer.c */
361 void ax25_ds_setup_timer(ax25_dev *);
362 void ax25_ds_set_timer(ax25_dev *);
363 void ax25_ds_del_timer(ax25_dev *);
364 void ax25_ds_timer(ax25_cb *);
365 void ax25_ds_t1_timeout(ax25_cb *);
366 void ax25_ds_heartbeat_expiry(ax25_cb *);
367 void ax25_ds_t3timer_expiry(ax25_cb *);
368 void ax25_ds_idletimer_expiry(ax25_cb *);
369
370 /* ax25_iface.c */
371
372 struct ax25_protocol {
373 struct ax25_protocol *next;
374 unsigned int pid;
375 int (*func)(struct sk_buff *, ax25_cb *);
376 };
377
378 void ax25_register_pid(struct ax25_protocol *ap);
379 void ax25_protocol_release(unsigned int);
380
381 struct ax25_linkfail {
382 struct hlist_node lf_node;
383 void (*func)(ax25_cb *, int);
384 };
385
386 void ax25_linkfail_register(struct ax25_linkfail *lf);
387 void ax25_linkfail_release(struct ax25_linkfail *lf);
388 int __must_check ax25_listen_register(const ax25_address *,
389 struct net_device *);
390 void ax25_listen_release(const ax25_address *, struct net_device *);
391 int(*ax25_protocol_function(unsigned int))(struct sk_buff *, ax25_cb *);
392 int ax25_listen_mine(const ax25_address *, struct net_device *);
393 void ax25_link_failed(ax25_cb *, int);
394 int ax25_protocol_is_registered(unsigned int);
395
396 /* ax25_in.c */
397 int ax25_rx_iframe(ax25_cb *, struct sk_buff *);
398 int ax25_kiss_rcv(struct sk_buff *, struct net_device *, struct packet_type *,
399 struct net_device *);
400
401 /* ax25_ip.c */
402 netdev_tx_t ax25_ip_xmit(struct sk_buff *skb);
403 extern const struct header_ops ax25_header_ops;
404
405 /* ax25_out.c */
406 ax25_cb *ax25_send_frame(struct sk_buff *, int, const ax25_address *,
407 ax25_address *, ax25_digi *, struct net_device *);
408 void ax25_output(ax25_cb *, int, struct sk_buff *);
409 void ax25_kick(ax25_cb *);
410 void ax25_transmit_buffer(ax25_cb *, struct sk_buff *, int);
411 void ax25_queue_xmit(struct sk_buff *skb, struct net_device *dev);
412 int ax25_check_iframes_acked(ax25_cb *, unsigned short);
413
414 /* ax25_route.c */
415 void ax25_rt_device_down(struct net_device *);
416 int ax25_rt_ioctl(unsigned int, void __user *);
417 extern const struct seq_operations ax25_rt_seqops;
418 ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev);
419 int ax25_rt_autobind(ax25_cb *, ax25_address *);
420 struct sk_buff *ax25_rt_build_path(struct sk_buff *, ax25_address *,
421 ax25_address *, ax25_digi *);
422 void ax25_rt_free(void);
423
424 /* ax25_std_in.c */
425 int ax25_std_frame_in(ax25_cb *, struct sk_buff *, int);
426
427 /* ax25_std_subr.c */
428 void ax25_std_nr_error_recovery(ax25_cb *);
429 void ax25_std_establish_data_link(ax25_cb *);
430 void ax25_std_transmit_enquiry(ax25_cb *);
431 void ax25_std_enquiry_response(ax25_cb *);
432 void ax25_std_timeout_response(ax25_cb *);
433
434 /* ax25_std_timer.c */
435 void ax25_std_heartbeat_expiry(ax25_cb *);
436 void ax25_std_t1timer_expiry(ax25_cb *);
437 void ax25_std_t2timer_expiry(ax25_cb *);
438 void ax25_std_t3timer_expiry(ax25_cb *);
439 void ax25_std_idletimer_expiry(ax25_cb *);
440
441 /* ax25_subr.c */
442 void ax25_clear_queues(ax25_cb *);
443 void ax25_frames_acked(ax25_cb *, unsigned short);
444 void ax25_requeue_frames(ax25_cb *);
445 int ax25_validate_nr(ax25_cb *, unsigned short);
446 int ax25_decode(ax25_cb *, struct sk_buff *, int *, int *, int *);
447 void ax25_send_control(ax25_cb *, int, int, int);
448 void ax25_return_dm(struct net_device *, ax25_address *, ax25_address *,
449 ax25_digi *);
450 void ax25_calculate_t1(ax25_cb *);
451 void ax25_calculate_rtt(ax25_cb *);
452 void ax25_disconnect(ax25_cb *, int);
453
454 /* ax25_timer.c */
455 void ax25_setup_timers(ax25_cb *);
456 void ax25_start_heartbeat(ax25_cb *);
457 void ax25_start_t1timer(ax25_cb *);
458 void ax25_start_t2timer(ax25_cb *);
459 void ax25_start_t3timer(ax25_cb *);
460 void ax25_start_idletimer(ax25_cb *);
461 void ax25_stop_heartbeat(ax25_cb *);
462 void ax25_stop_t1timer(ax25_cb *);
463 void ax25_stop_t2timer(ax25_cb *);
464 void ax25_stop_t3timer(ax25_cb *);
465 void ax25_stop_idletimer(ax25_cb *);
466 int ax25_t1timer_running(ax25_cb *);
467 unsigned long ax25_display_timer(struct timer_list *);
468
469 /* ax25_uid.c */
470 extern int ax25_uid_policy;
471 ax25_uid_assoc *ax25_findbyuid(kuid_t);
472 int __must_check ax25_uid_ioctl(int, struct sockaddr_ax25 *);
473 extern const struct seq_operations ax25_uid_seqops;
474 void ax25_uid_free(void);
475
476 /* sysctl_net_ax25.c */
477 #ifdef CONFIG_SYSCTL
478 int ax25_register_dev_sysctl(ax25_dev *ax25_dev);
479 void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev);
480 #else
ax25_register_dev_sysctl(ax25_dev * ax25_dev)481 static inline int ax25_register_dev_sysctl(ax25_dev *ax25_dev) { return 0; }
ax25_unregister_dev_sysctl(ax25_dev * ax25_dev)482 static inline void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev) {}
483 #endif /* CONFIG_SYSCTL */
484
485 #endif
486