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 #ifdef CONFIG_AX25_DAMA_SLAVE
143 AX25_VALUES_DS_TIMEOUT, /* DAMA Slave timeout */
144 #endif
145 AX25_MAX_VALUES /* THIS MUST REMAIN THE LAST ENTRY OF THIS LIST */
146 };
147
148 #define AX25_DEF_IPDEFMODE 0 /* Datagram */
149 #define AX25_DEF_AXDEFMODE 0 /* Normal */
150 #define AX25_DEF_BACKOFF 1 /* Linear backoff */
151 #define AX25_DEF_CONMODE 2 /* Connected mode allowed */
152 #define AX25_DEF_WINDOW 2 /* Window=2 */
153 #define AX25_DEF_EWINDOW 32 /* Module-128 Window=32 */
154 #define AX25_DEF_T1 10000 /* T1=10s */
155 #define AX25_DEF_T2 3000 /* T2=3s */
156 #define AX25_DEF_T3 300000 /* T3=300s */
157 #define AX25_DEF_N2 10 /* N2=10 */
158 #define AX25_DEF_IDLE 0 /* Idle=None */
159 #define AX25_DEF_PACLEN 256 /* Paclen=256 */
160 #define AX25_DEF_PROTOCOL AX25_PROTO_STD_SIMPLEX /* Standard AX.25 */
161 #define AX25_DEF_DS_TIMEOUT 180000 /* DAMA timeout 3 minutes */
162
163 typedef struct ax25_uid_assoc {
164 struct hlist_node uid_node;
165 refcount_t refcount;
166 kuid_t uid;
167 ax25_address call;
168 } ax25_uid_assoc;
169
170 #define ax25_uid_for_each(__ax25, list) \
171 hlist_for_each_entry(__ax25, list, uid_node)
172
173 #define ax25_uid_hold(ax25) \
174 refcount_inc(&((ax25)->refcount))
175
ax25_uid_put(ax25_uid_assoc * assoc)176 static inline void ax25_uid_put(ax25_uid_assoc *assoc)
177 {
178 if (refcount_dec_and_test(&assoc->refcount)) {
179 kfree(assoc);
180 }
181 }
182
183 typedef struct {
184 ax25_address calls[AX25_MAX_DIGIS];
185 unsigned char repeated[AX25_MAX_DIGIS];
186 unsigned char ndigi;
187 signed char lastrepeat;
188 } ax25_digi;
189
190 typedef struct ax25_route {
191 struct ax25_route *next;
192 ax25_address callsign;
193 struct net_device *dev;
194 ax25_digi *digipeat;
195 char ip_mode;
196 } ax25_route;
197
198 void __ax25_put_route(ax25_route *ax25_rt);
199
200 extern rwlock_t ax25_route_lock;
201
ax25_route_lock_use(void)202 static inline void ax25_route_lock_use(void)
203 {
204 read_lock(&ax25_route_lock);
205 }
206
ax25_route_lock_unuse(void)207 static inline void ax25_route_lock_unuse(void)
208 {
209 read_unlock(&ax25_route_lock);
210 }
211
212 typedef struct {
213 char slave; /* slave_mode? */
214 struct timer_list slave_timer; /* timeout timer */
215 unsigned short slave_timeout; /* when? */
216 } ax25_dama_info;
217
218 struct ctl_table;
219
220 typedef struct ax25_dev {
221 struct list_head list;
222
223 struct net_device *dev;
224 netdevice_tracker dev_tracker;
225
226 struct net_device *forward;
227 struct ctl_table_header *sysheader;
228 int values[AX25_MAX_VALUES];
229 #if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER)
230 ax25_dama_info dama;
231 #endif
232 refcount_t refcount;
233 bool device_up;
234 struct rcu_head rcu;
235 } ax25_dev;
236
237 typedef struct ax25_cb {
238 struct hlist_node ax25_node;
239 ax25_address source_addr, dest_addr;
240 ax25_digi *digipeat;
241 ax25_dev *ax25_dev;
242 netdevice_tracker dev_tracker;
243 unsigned char iamdigi;
244 unsigned char state, modulus, pidincl;
245 unsigned short vs, vr, va;
246 unsigned char condition, backoff;
247 unsigned char n2, n2count;
248 struct timer_list t1timer, t2timer, t3timer, idletimer;
249 unsigned long t1, t2, t3, idle, rtt;
250 unsigned short paclen, fragno, fraglen;
251 struct sk_buff_head write_queue;
252 struct sk_buff_head reseq_queue;
253 struct sk_buff_head ack_queue;
254 struct sk_buff_head frag_queue;
255 unsigned char window;
256 struct timer_list timer, dtimer;
257 struct sock *sk; /* Backlink to socket */
258 refcount_t refcount;
259 } ax25_cb;
260
261 struct ax25_sock {
262 struct sock sk;
263 struct ax25_cb *cb;
264 };
265
266 #define ax25_sk(ptr) container_of_const(ptr, struct ax25_sock, sk)
267
sk_to_ax25(const struct sock * sk)268 static inline struct ax25_cb *sk_to_ax25(const struct sock *sk)
269 {
270 return ax25_sk(sk)->cb;
271 }
272
273 #define ax25_for_each(__ax25, list) \
274 hlist_for_each_entry(__ax25, list, ax25_node)
275
276 #define ax25_cb_hold(__ax25) \
277 refcount_inc(&((__ax25)->refcount))
278
ax25_cb_put(ax25_cb * ax25)279 static __inline__ void ax25_cb_put(ax25_cb *ax25)
280 {
281 if (refcount_dec_and_test(&ax25->refcount)) {
282 kfree(ax25->digipeat);
283 kfree(ax25);
284 }
285 }
286
ax25_dev_hold(ax25_dev * ax25_dev)287 static inline void ax25_dev_hold(ax25_dev *ax25_dev)
288 {
289 refcount_inc(&ax25_dev->refcount);
290 }
291
ax25_dev_put(ax25_dev * ax25_dev)292 static inline void ax25_dev_put(ax25_dev *ax25_dev)
293 {
294 if (refcount_dec_and_test(&ax25_dev->refcount))
295 kfree_rcu(ax25_dev, rcu);
296 }
ax25_type_trans(struct sk_buff * skb,struct net_device * dev)297 static inline __be16 ax25_type_trans(struct sk_buff *skb, struct net_device *dev)
298 {
299 skb->dev = dev;
300 skb_reset_mac_header(skb);
301 skb->pkt_type = PACKET_HOST;
302 return htons(ETH_P_AX25);
303 }
304
305 /* af_ax25.c */
306 extern struct hlist_head ax25_list;
307 extern spinlock_t ax25_list_lock;
308 void ax25_cb_add(ax25_cb *);
309 struct sock *ax25_find_listener(ax25_address *, int, struct net_device *, int);
310 struct sock *ax25_get_socket(ax25_address *, ax25_address *, int);
311 ax25_cb *ax25_find_cb(const ax25_address *, ax25_address *, ax25_digi *,
312 struct net_device *);
313 void ax25_send_to_raw(ax25_address *, struct sk_buff *, int);
314 void ax25_destroy_socket(ax25_cb *);
315 ax25_cb * __must_check ax25_create_cb(void);
316 void ax25_fillin_cb(ax25_cb *, ax25_dev *);
317 struct sock *ax25_make_new(struct sock *, struct ax25_dev *);
318
319 /* ax25_addr.c */
320 extern const ax25_address ax25_bcast;
321 extern const ax25_address ax25_defaddr;
322 extern const ax25_address null_ax25_address;
323 char *ax2asc(char *buf, const ax25_address *);
324 void asc2ax(ax25_address *addr, const char *callsign);
325 int ax25cmp(const ax25_address *, const ax25_address *);
326 int ax25digicmp(const ax25_digi *, const ax25_digi *);
327 const unsigned char *ax25_addr_parse(const unsigned char *, int,
328 ax25_address *, ax25_address *, ax25_digi *, int *, int *);
329 int ax25_addr_build(unsigned char *, const ax25_address *,
330 const ax25_address *, const ax25_digi *, int, int);
331 int ax25_addr_size(const ax25_digi *);
332 void ax25_digi_invert(const ax25_digi *, ax25_digi *);
333
334 /* ax25_dev.c */
335 extern spinlock_t ax25_dev_lock;
336
337 #if IS_ENABLED(CONFIG_AX25)
ax25_dev_ax25dev(const struct net_device * dev)338 static inline ax25_dev *ax25_dev_ax25dev(const struct net_device *dev)
339 {
340 return rcu_dereference_rtnl(dev->ax25_ptr);
341 }
342 #endif
343
344 ax25_dev *ax25_addr_ax25dev(ax25_address *);
345 void ax25_dev_device_up(struct net_device *);
346 void ax25_dev_device_down(struct net_device *);
347 int ax25_fwd_ioctl(unsigned int, struct ax25_fwd_struct *);
348 struct net_device *ax25_fwd_dev(struct net_device *);
349 void ax25_dev_free(void);
350
351 /* ax25_ds_in.c */
352 int ax25_ds_frame_in(ax25_cb *, struct sk_buff *, int);
353
354 /* ax25_ds_subr.c */
355 void ax25_ds_nr_error_recovery(ax25_cb *);
356 void ax25_ds_enquiry_response(ax25_cb *);
357 void ax25_ds_establish_data_link(ax25_cb *);
358 void ax25_dev_dama_off(ax25_dev *);
359 void ax25_dama_on(ax25_cb *);
360 void ax25_dama_off(ax25_cb *);
361
362 /* ax25_ds_timer.c */
363 void ax25_ds_setup_timer(ax25_dev *);
364 void ax25_ds_set_timer(ax25_dev *);
365 void ax25_ds_del_timer(ax25_dev *);
366 void ax25_ds_timer(ax25_cb *);
367 void ax25_ds_t1_timeout(ax25_cb *);
368 void ax25_ds_heartbeat_expiry(ax25_cb *);
369 void ax25_ds_t3timer_expiry(ax25_cb *);
370 void ax25_ds_idletimer_expiry(ax25_cb *);
371
372 /* ax25_iface.c */
373
374 struct ax25_protocol {
375 struct ax25_protocol *next;
376 unsigned int pid;
377 int (*func)(struct sk_buff *, ax25_cb *);
378 };
379
380 void ax25_register_pid(struct ax25_protocol *ap);
381 void ax25_protocol_release(unsigned int);
382
383 struct ax25_linkfail {
384 struct hlist_node lf_node;
385 void (*func)(ax25_cb *, int);
386 };
387
388 void ax25_linkfail_register(struct ax25_linkfail *lf);
389 void ax25_linkfail_release(struct ax25_linkfail *lf);
390 int __must_check ax25_listen_register(const ax25_address *,
391 struct net_device *);
392 void ax25_listen_release(const ax25_address *, struct net_device *);
393 int(*ax25_protocol_function(unsigned int))(struct sk_buff *, ax25_cb *);
394 int ax25_listen_mine(const ax25_address *, struct net_device *);
395 void ax25_link_failed(ax25_cb *, int);
396 int ax25_protocol_is_registered(unsigned int);
397
398 /* ax25_in.c */
399 int ax25_rx_iframe(ax25_cb *, struct sk_buff *);
400 int ax25_kiss_rcv(struct sk_buff *, struct net_device *, struct packet_type *,
401 struct net_device *);
402
403 /* ax25_ip.c */
404 netdev_tx_t ax25_ip_xmit(struct sk_buff *skb);
405 extern const struct header_ops ax25_header_ops;
406
407 /* ax25_out.c */
408 ax25_cb *ax25_send_frame(struct sk_buff *, int, const ax25_address *,
409 ax25_address *, ax25_digi *, struct net_device *);
410 void ax25_output(ax25_cb *, int, struct sk_buff *);
411 void ax25_kick(ax25_cb *);
412 void ax25_transmit_buffer(ax25_cb *, struct sk_buff *, int);
413 void ax25_queue_xmit(struct sk_buff *skb, struct net_device *dev);
414 int ax25_check_iframes_acked(ax25_cb *, unsigned short);
415
416 /* ax25_route.c */
417 void ax25_rt_device_down(struct net_device *);
418 int ax25_rt_ioctl(unsigned int, void __user *);
419 extern const struct seq_operations ax25_rt_seqops;
420 ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev);
421 struct sk_buff *ax25_rt_build_path(struct sk_buff *, ax25_address *,
422 ax25_address *, ax25_digi *);
423 void ax25_rt_free(void);
424
425 /* ax25_std_in.c */
426 int ax25_std_frame_in(ax25_cb *, struct sk_buff *, int);
427
428 /* ax25_std_subr.c */
429 void ax25_std_nr_error_recovery(ax25_cb *);
430 void ax25_std_establish_data_link(ax25_cb *);
431 void ax25_std_transmit_enquiry(ax25_cb *);
432 void ax25_std_enquiry_response(ax25_cb *);
433 void ax25_std_timeout_response(ax25_cb *);
434
435 /* ax25_std_timer.c */
436 void ax25_std_heartbeat_expiry(ax25_cb *);
437 void ax25_std_t1timer_expiry(ax25_cb *);
438 void ax25_std_t2timer_expiry(ax25_cb *);
439 void ax25_std_t3timer_expiry(ax25_cb *);
440 void ax25_std_idletimer_expiry(ax25_cb *);
441
442 /* ax25_subr.c */
443 void ax25_clear_queues(ax25_cb *);
444 void ax25_frames_acked(ax25_cb *, unsigned short);
445 void ax25_requeue_frames(ax25_cb *);
446 int ax25_validate_nr(ax25_cb *, unsigned short);
447 int ax25_decode(ax25_cb *, struct sk_buff *, int *, int *, int *);
448 void ax25_send_control(ax25_cb *, int, int, int);
449 void ax25_return_dm(struct net_device *, ax25_address *, ax25_address *,
450 ax25_digi *);
451 void ax25_calculate_t1(ax25_cb *);
452 void ax25_calculate_rtt(ax25_cb *);
453 void ax25_disconnect(ax25_cb *, int);
454
455 /* ax25_timer.c */
456 void ax25_setup_timers(ax25_cb *);
457 void ax25_start_heartbeat(ax25_cb *);
458 void ax25_start_t1timer(ax25_cb *);
459 void ax25_start_t2timer(ax25_cb *);
460 void ax25_start_t3timer(ax25_cb *);
461 void ax25_start_idletimer(ax25_cb *);
462 void ax25_stop_heartbeat(ax25_cb *);
463 void ax25_stop_t1timer(ax25_cb *);
464 void ax25_stop_t2timer(ax25_cb *);
465 void ax25_stop_t3timer(ax25_cb *);
466 void ax25_stop_idletimer(ax25_cb *);
467 int ax25_t1timer_running(ax25_cb *);
468 unsigned long ax25_display_timer(struct timer_list *);
469
470 /* ax25_uid.c */
471 extern int ax25_uid_policy;
472 ax25_uid_assoc *ax25_findbyuid(kuid_t);
473 int __must_check ax25_uid_ioctl(int, struct sockaddr_ax25 *);
474 extern const struct seq_operations ax25_uid_seqops;
475 void ax25_uid_free(void);
476
477 /* sysctl_net_ax25.c */
478 #ifdef CONFIG_SYSCTL
479 int ax25_register_dev_sysctl(ax25_dev *ax25_dev);
480 void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev);
481 #else
ax25_register_dev_sysctl(ax25_dev * ax25_dev)482 static inline int ax25_register_dev_sysctl(ax25_dev *ax25_dev) { return 0; }
ax25_unregister_dev_sysctl(ax25_dev * ax25_dev)483 static inline void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev) {}
484 #endif /* CONFIG_SYSCTL */
485
486 #endif
487