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
103enum {
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
114enum {
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
128enum {
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
163typedef 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
176static inline void ax25_uid_put(ax25_uid_assoc *assoc)
177{
178 if (refcount_dec_and_test(r: &assoc->refcount)) {
179 kfree(objp: assoc);
180 }
181}
182
183typedef 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
190typedef 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
198void __ax25_put_route(ax25_route *ax25_rt);
199
200extern rwlock_t ax25_route_lock;
201
202static inline void ax25_route_lock_use(void)
203{
204 read_lock(&ax25_route_lock);
205}
206
207static inline void ax25_route_lock_unuse(void)
208{
209 read_unlock(&ax25_route_lock);
210}
211
212typedef 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
218struct ctl_table;
219
220typedef 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
237typedef 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
261struct 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
268static 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
279static __inline__ void ax25_cb_put(ax25_cb *ax25)
280{
281 if (refcount_dec_and_test(r: &ax25->refcount)) {
282 kfree(objp: ax25->digipeat);
283 kfree(objp: ax25);
284 }
285}
286
287static inline void ax25_dev_hold(ax25_dev *ax25_dev)
288{
289 refcount_inc(r: &ax25_dev->refcount);
290}
291
292static inline void ax25_dev_put(ax25_dev *ax25_dev)
293{
294 if (refcount_dec_and_test(r: &ax25_dev->refcount))
295 kfree_rcu(ax25_dev, rcu);
296}
297static 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 */
306extern struct hlist_head ax25_list;
307extern spinlock_t ax25_list_lock;
308void ax25_cb_add(ax25_cb *);
309struct sock *ax25_find_listener(ax25_address *, int, struct net_device *, int);
310struct sock *ax25_get_socket(ax25_address *, ax25_address *, int);
311ax25_cb *ax25_find_cb(const ax25_address *, ax25_address *, ax25_digi *,
312 struct net_device *);
313void ax25_send_to_raw(ax25_address *, struct sk_buff *, int);
314void ax25_destroy_socket(ax25_cb *);
315ax25_cb * __must_check ax25_create_cb(void);
316void ax25_fillin_cb(ax25_cb *, ax25_dev *);
317struct sock *ax25_make_new(struct sock *, struct ax25_dev *);
318
319/* ax25_addr.c */
320extern const ax25_address ax25_bcast;
321extern const ax25_address ax25_defaddr;
322extern const ax25_address null_ax25_address;
323char *ax2asc(char *buf, const ax25_address *);
324void asc2ax(ax25_address *addr, const char *callsign);
325int ax25cmp(const ax25_address *, const ax25_address *);
326int ax25digicmp(const ax25_digi *, const ax25_digi *);
327const unsigned char *ax25_addr_parse(const unsigned char *, int,
328 ax25_address *, ax25_address *, ax25_digi *, int *, int *);
329int ax25_addr_build(unsigned char *, const ax25_address *,
330 const ax25_address *, const ax25_digi *, int, int);
331int ax25_addr_size(const ax25_digi *);
332void ax25_digi_invert(const ax25_digi *, ax25_digi *);
333
334/* ax25_dev.c */
335extern spinlock_t ax25_dev_lock;
336
337#if IS_ENABLED(CONFIG_AX25)
338static inline ax25_dev *ax25_dev_ax25dev(const struct net_device *dev)
339{
340 return rcu_dereference_rtnl(dev->ax25_ptr);
341}
342#endif
343
344ax25_dev *ax25_addr_ax25dev(ax25_address *);
345void ax25_dev_device_up(struct net_device *);
346void ax25_dev_device_down(struct net_device *);
347int ax25_fwd_ioctl(unsigned int, struct ax25_fwd_struct *);
348struct net_device *ax25_fwd_dev(struct net_device *);
349void ax25_dev_free(void);
350
351/* ax25_ds_in.c */
352int ax25_ds_frame_in(ax25_cb *, struct sk_buff *, int);
353
354/* ax25_ds_subr.c */
355void ax25_ds_nr_error_recovery(ax25_cb *);
356void ax25_ds_enquiry_response(ax25_cb *);
357void ax25_ds_establish_data_link(ax25_cb *);
358void ax25_dev_dama_off(ax25_dev *);
359void ax25_dama_on(ax25_cb *);
360void ax25_dama_off(ax25_cb *);
361
362/* ax25_ds_timer.c */
363void ax25_ds_setup_timer(ax25_dev *);
364void ax25_ds_set_timer(ax25_dev *);
365void ax25_ds_del_timer(ax25_dev *);
366void ax25_ds_timer(ax25_cb *);
367void ax25_ds_t1_timeout(ax25_cb *);
368void ax25_ds_heartbeat_expiry(ax25_cb *);
369void ax25_ds_t3timer_expiry(ax25_cb *);
370void ax25_ds_idletimer_expiry(ax25_cb *);
371
372/* ax25_iface.c */
373
374struct ax25_protocol {
375 struct ax25_protocol *next;
376 unsigned int pid;
377 int (*func)(struct sk_buff *, ax25_cb *);
378};
379
380void ax25_register_pid(struct ax25_protocol *ap);
381void ax25_protocol_release(unsigned int);
382
383struct ax25_linkfail {
384 struct hlist_node lf_node;
385 void (*func)(ax25_cb *, int);
386};
387
388void ax25_linkfail_register(struct ax25_linkfail *lf);
389void ax25_linkfail_release(struct ax25_linkfail *lf);
390int __must_check ax25_listen_register(const ax25_address *,
391 struct net_device *);
392void ax25_listen_release(const ax25_address *, struct net_device *);
393int(*ax25_protocol_function(unsigned int))(struct sk_buff *, ax25_cb *);
394int ax25_listen_mine(const ax25_address *, struct net_device *);
395void ax25_link_failed(ax25_cb *, int);
396int ax25_protocol_is_registered(unsigned int);
397
398/* ax25_in.c */
399int ax25_rx_iframe(ax25_cb *, struct sk_buff *);
400int ax25_kiss_rcv(struct sk_buff *, struct net_device *, struct packet_type *,
401 struct net_device *);
402
403/* ax25_ip.c */
404netdev_tx_t ax25_ip_xmit(struct sk_buff *skb);
405extern const struct header_ops ax25_header_ops;
406
407/* ax25_out.c */
408ax25_cb *ax25_send_frame(struct sk_buff *, int, const ax25_address *,
409 ax25_address *, ax25_digi *, struct net_device *);
410void ax25_output(ax25_cb *, int, struct sk_buff *);
411void ax25_kick(ax25_cb *);
412void ax25_transmit_buffer(ax25_cb *, struct sk_buff *, int);
413void ax25_queue_xmit(struct sk_buff *skb, struct net_device *dev);
414int ax25_check_iframes_acked(ax25_cb *, unsigned short);
415
416/* ax25_route.c */
417void ax25_rt_device_down(struct net_device *);
418int ax25_rt_ioctl(unsigned int, void __user *);
419extern const struct seq_operations ax25_rt_seqops;
420ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev);
421struct sk_buff *ax25_rt_build_path(struct sk_buff *, ax25_address *,
422 ax25_address *, ax25_digi *);
423void ax25_rt_free(void);
424
425/* ax25_std_in.c */
426int ax25_std_frame_in(ax25_cb *, struct sk_buff *, int);
427
428/* ax25_std_subr.c */
429void ax25_std_nr_error_recovery(ax25_cb *);
430void ax25_std_establish_data_link(ax25_cb *);
431void ax25_std_transmit_enquiry(ax25_cb *);
432void ax25_std_enquiry_response(ax25_cb *);
433void ax25_std_timeout_response(ax25_cb *);
434
435/* ax25_std_timer.c */
436void ax25_std_heartbeat_expiry(ax25_cb *);
437void ax25_std_t1timer_expiry(ax25_cb *);
438void ax25_std_t2timer_expiry(ax25_cb *);
439void ax25_std_t3timer_expiry(ax25_cb *);
440void ax25_std_idletimer_expiry(ax25_cb *);
441
442/* ax25_subr.c */
443void ax25_clear_queues(ax25_cb *);
444void ax25_frames_acked(ax25_cb *, unsigned short);
445void ax25_requeue_frames(ax25_cb *);
446int ax25_validate_nr(ax25_cb *, unsigned short);
447int ax25_decode(ax25_cb *, struct sk_buff *, int *, int *, int *);
448void ax25_send_control(ax25_cb *, int, int, int);
449void ax25_return_dm(struct net_device *, ax25_address *, ax25_address *,
450 ax25_digi *);
451void ax25_calculate_t1(ax25_cb *);
452void ax25_calculate_rtt(ax25_cb *);
453void ax25_disconnect(ax25_cb *, int);
454
455/* ax25_timer.c */
456void ax25_setup_timers(ax25_cb *);
457void ax25_start_heartbeat(ax25_cb *);
458void ax25_start_t1timer(ax25_cb *);
459void ax25_start_t2timer(ax25_cb *);
460void ax25_start_t3timer(ax25_cb *);
461void ax25_start_idletimer(ax25_cb *);
462void ax25_stop_heartbeat(ax25_cb *);
463void ax25_stop_t1timer(ax25_cb *);
464void ax25_stop_t2timer(ax25_cb *);
465void ax25_stop_t3timer(ax25_cb *);
466void ax25_stop_idletimer(ax25_cb *);
467int ax25_t1timer_running(ax25_cb *);
468unsigned long ax25_display_timer(struct timer_list *);
469
470/* ax25_uid.c */
471extern int ax25_uid_policy;
472ax25_uid_assoc *ax25_findbyuid(kuid_t);
473int __must_check ax25_uid_ioctl(int, struct sockaddr_ax25 *);
474extern const struct seq_operations ax25_uid_seqops;
475void ax25_uid_free(void);
476
477/* sysctl_net_ax25.c */
478#ifdef CONFIG_SYSCTL
479int ax25_register_dev_sysctl(ax25_dev *ax25_dev);
480void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev);
481#else
482static inline int ax25_register_dev_sysctl(ax25_dev *ax25_dev) { return 0; }
483static inline void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev) {}
484#endif /* CONFIG_SYSCTL */
485
486#endif
487