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 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
161typedef 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
174static inline void ax25_uid_put(ax25_uid_assoc *assoc)
175{
176 if (refcount_dec_and_test(&assoc->refcount)) {
177 kfree(assoc);
178 }
179}
180
181typedef 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
188typedef struct ax25_route {
189 struct ax25_route *next;
190 refcount_t refcount;
191 ax25_address callsign;
192 struct net_device *dev;
193 ax25_digi *digipeat;
194 char ip_mode;
195} ax25_route;
196
197static inline void ax25_hold_route(ax25_route *ax25_rt)
198{
199 refcount_inc(&ax25_rt->refcount);
200}
201
202void __ax25_put_route(ax25_route *ax25_rt);
203
204extern rwlock_t ax25_route_lock;
205
206static inline void ax25_route_lock_use(void)
207{
208 read_lock(&ax25_route_lock);
209}
210
211static inline void ax25_route_lock_unuse(void)
212{
213 read_unlock(&ax25_route_lock);
214}
215
216static inline void ax25_put_route(ax25_route *ax25_rt)
217{
218 if (refcount_dec_and_test(&ax25_rt->refcount))
219 __ax25_put_route(ax25_rt);
220}
221
222typedef struct {
223 char slave; /* slave_mode? */
224 struct timer_list slave_timer; /* timeout timer */
225 unsigned short slave_timeout; /* when? */
226} ax25_dama_info;
227
228struct ctl_table;
229
230typedef struct ax25_dev {
231 struct ax25_dev *next;
232 struct net_device *dev;
233 struct net_device *forward;
234 struct ctl_table_header *sysheader;
235 int values[AX25_MAX_VALUES];
236#if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER)
237 ax25_dama_info dama;
238#endif
239} ax25_dev;
240
241typedef struct ax25_cb {
242 struct hlist_node ax25_node;
243 ax25_address source_addr, dest_addr;
244 ax25_digi *digipeat;
245 ax25_dev *ax25_dev;
246 unsigned char iamdigi;
247 unsigned char state, modulus, pidincl;
248 unsigned short vs, vr, va;
249 unsigned char condition, backoff;
250 unsigned char n2, n2count;
251 struct timer_list t1timer, t2timer, t3timer, idletimer;
252 unsigned long t1, t2, t3, idle, rtt;
253 unsigned short paclen, fragno, fraglen;
254 struct sk_buff_head write_queue;
255 struct sk_buff_head reseq_queue;
256 struct sk_buff_head ack_queue;
257 struct sk_buff_head frag_queue;
258 unsigned char window;
259 struct timer_list timer, dtimer;
260 struct sock *sk; /* Backlink to socket */
261 refcount_t refcount;
262} ax25_cb;
263
264struct ax25_sock {
265 struct sock sk;
266 struct ax25_cb *cb;
267};
268
269static inline struct ax25_sock *ax25_sk(const struct sock *sk)
270{
271 return (struct ax25_sock *) sk;
272}
273
274static inline struct ax25_cb *sk_to_ax25(const struct sock *sk)
275{
276 return ax25_sk(sk)->cb;
277}
278
279#define ax25_for_each(__ax25, list) \
280 hlist_for_each_entry(__ax25, list, ax25_node)
281
282#define ax25_cb_hold(__ax25) \
283 refcount_inc(&((__ax25)->refcount))
284
285static __inline__ void ax25_cb_put(ax25_cb *ax25)
286{
287 if (refcount_dec_and_test(&ax25->refcount)) {
288 kfree(ax25->digipeat);
289 kfree(ax25);
290 }
291}
292
293static inline __be16 ax25_type_trans(struct sk_buff *skb, struct net_device *dev)
294{
295 skb->dev = dev;
296 skb_reset_mac_header(skb);
297 skb->pkt_type = PACKET_HOST;
298 return htons(ETH_P_AX25);
299}
300
301/* af_ax25.c */
302extern struct hlist_head ax25_list;
303extern spinlock_t ax25_list_lock;
304void ax25_cb_add(ax25_cb *);
305struct sock *ax25_find_listener(ax25_address *, int, struct net_device *, int);
306struct sock *ax25_get_socket(ax25_address *, ax25_address *, int);
307ax25_cb *ax25_find_cb(ax25_address *, ax25_address *, ax25_digi *,
308 struct net_device *);
309void ax25_send_to_raw(ax25_address *, struct sk_buff *, int);
310void ax25_destroy_socket(ax25_cb *);
311ax25_cb * __must_check ax25_create_cb(void);
312void ax25_fillin_cb(ax25_cb *, ax25_dev *);
313struct sock *ax25_make_new(struct sock *, struct ax25_dev *);
314
315/* ax25_addr.c */
316extern const ax25_address ax25_bcast;
317extern const ax25_address ax25_defaddr;
318extern const ax25_address null_ax25_address;
319char *ax2asc(char *buf, const ax25_address *);
320void asc2ax(ax25_address *addr, const char *callsign);
321int ax25cmp(const ax25_address *, const ax25_address *);
322int ax25digicmp(const ax25_digi *, const ax25_digi *);
323const unsigned char *ax25_addr_parse(const unsigned char *, int,
324 ax25_address *, ax25_address *, ax25_digi *, int *, int *);
325int ax25_addr_build(unsigned char *, const ax25_address *,
326 const ax25_address *, const ax25_digi *, int, int);
327int ax25_addr_size(const ax25_digi *);
328void ax25_digi_invert(const ax25_digi *, ax25_digi *);
329
330/* ax25_dev.c */
331extern ax25_dev *ax25_dev_list;
332extern spinlock_t ax25_dev_lock;
333
334#if IS_ENABLED(CONFIG_AX25)
335static inline ax25_dev *ax25_dev_ax25dev(struct net_device *dev)
336{
337 return dev->ax25_ptr;
338}
339#endif
340
341ax25_dev *ax25_addr_ax25dev(ax25_address *);
342void ax25_dev_device_up(struct net_device *);
343void ax25_dev_device_down(struct net_device *);
344int ax25_fwd_ioctl(unsigned int, struct ax25_fwd_struct *);
345struct net_device *ax25_fwd_dev(struct net_device *);
346void ax25_dev_free(void);
347
348/* ax25_ds_in.c */
349int ax25_ds_frame_in(ax25_cb *, struct sk_buff *, int);
350
351/* ax25_ds_subr.c */
352void ax25_ds_nr_error_recovery(ax25_cb *);
353void ax25_ds_enquiry_response(ax25_cb *);
354void ax25_ds_establish_data_link(ax25_cb *);
355void ax25_dev_dama_off(ax25_dev *);
356void ax25_dama_on(ax25_cb *);
357void ax25_dama_off(ax25_cb *);
358
359/* ax25_ds_timer.c */
360void ax25_ds_setup_timer(ax25_dev *);
361void ax25_ds_set_timer(ax25_dev *);
362void ax25_ds_del_timer(ax25_dev *);
363void ax25_ds_timer(ax25_cb *);
364void ax25_ds_t1_timeout(ax25_cb *);
365void ax25_ds_heartbeat_expiry(ax25_cb *);
366void ax25_ds_t3timer_expiry(ax25_cb *);
367void ax25_ds_idletimer_expiry(ax25_cb *);
368
369/* ax25_iface.c */
370
371struct ax25_protocol {
372 struct ax25_protocol *next;
373 unsigned int pid;
374 int (*func)(struct sk_buff *, ax25_cb *);
375};
376
377void ax25_register_pid(struct ax25_protocol *ap);
378void ax25_protocol_release(unsigned int);
379
380struct ax25_linkfail {
381 struct hlist_node lf_node;
382 void (*func)(ax25_cb *, int);
383};
384
385void ax25_linkfail_register(struct ax25_linkfail *lf);
386void ax25_linkfail_release(struct ax25_linkfail *lf);
387int __must_check ax25_listen_register(ax25_address *, struct net_device *);
388void ax25_listen_release(ax25_address *, struct net_device *);
389int(*ax25_protocol_function(unsigned int))(struct sk_buff *, ax25_cb *);
390int ax25_listen_mine(ax25_address *, struct net_device *);
391void ax25_link_failed(ax25_cb *, int);
392int ax25_protocol_is_registered(unsigned int);
393
394/* ax25_in.c */
395int ax25_rx_iframe(ax25_cb *, struct sk_buff *);
396int ax25_kiss_rcv(struct sk_buff *, struct net_device *, struct packet_type *,
397 struct net_device *);
398
399/* ax25_ip.c */
400netdev_tx_t ax25_ip_xmit(struct sk_buff *skb);
401extern const struct header_ops ax25_header_ops;
402
403/* ax25_out.c */
404ax25_cb *ax25_send_frame(struct sk_buff *, int, ax25_address *, ax25_address *,
405 ax25_digi *, struct net_device *);
406void ax25_output(ax25_cb *, int, struct sk_buff *);
407void ax25_kick(ax25_cb *);
408void ax25_transmit_buffer(ax25_cb *, struct sk_buff *, int);
409void ax25_queue_xmit(struct sk_buff *skb, struct net_device *dev);
410int ax25_check_iframes_acked(ax25_cb *, unsigned short);
411
412/* ax25_route.c */
413void ax25_rt_device_down(struct net_device *);
414int ax25_rt_ioctl(unsigned int, void __user *);
415extern const struct seq_operations ax25_rt_seqops;
416ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev);
417int ax25_rt_autobind(ax25_cb *, ax25_address *);
418struct sk_buff *ax25_rt_build_path(struct sk_buff *, ax25_address *,
419 ax25_address *, ax25_digi *);
420void ax25_rt_free(void);
421
422/* ax25_std_in.c */
423int ax25_std_frame_in(ax25_cb *, struct sk_buff *, int);
424
425/* ax25_std_subr.c */
426void ax25_std_nr_error_recovery(ax25_cb *);
427void ax25_std_establish_data_link(ax25_cb *);
428void ax25_std_transmit_enquiry(ax25_cb *);
429void ax25_std_enquiry_response(ax25_cb *);
430void ax25_std_timeout_response(ax25_cb *);
431
432/* ax25_std_timer.c */
433void ax25_std_heartbeat_expiry(ax25_cb *);
434void ax25_std_t1timer_expiry(ax25_cb *);
435void ax25_std_t2timer_expiry(ax25_cb *);
436void ax25_std_t3timer_expiry(ax25_cb *);
437void ax25_std_idletimer_expiry(ax25_cb *);
438
439/* ax25_subr.c */
440void ax25_clear_queues(ax25_cb *);
441void ax25_frames_acked(ax25_cb *, unsigned short);
442void ax25_requeue_frames(ax25_cb *);
443int ax25_validate_nr(ax25_cb *, unsigned short);
444int ax25_decode(ax25_cb *, struct sk_buff *, int *, int *, int *);
445void ax25_send_control(ax25_cb *, int, int, int);
446void ax25_return_dm(struct net_device *, ax25_address *, ax25_address *,
447 ax25_digi *);
448void ax25_calculate_t1(ax25_cb *);
449void ax25_calculate_rtt(ax25_cb *);
450void ax25_disconnect(ax25_cb *, int);
451
452/* ax25_timer.c */
453void ax25_setup_timers(ax25_cb *);
454void ax25_start_heartbeat(ax25_cb *);
455void ax25_start_t1timer(ax25_cb *);
456void ax25_start_t2timer(ax25_cb *);
457void ax25_start_t3timer(ax25_cb *);
458void ax25_start_idletimer(ax25_cb *);
459void ax25_stop_heartbeat(ax25_cb *);
460void ax25_stop_t1timer(ax25_cb *);
461void ax25_stop_t2timer(ax25_cb *);
462void ax25_stop_t3timer(ax25_cb *);
463void ax25_stop_idletimer(ax25_cb *);
464int ax25_t1timer_running(ax25_cb *);
465unsigned long ax25_display_timer(struct timer_list *);
466
467/* ax25_uid.c */
468extern int ax25_uid_policy;
469ax25_uid_assoc *ax25_findbyuid(kuid_t);
470int __must_check ax25_uid_ioctl(int, struct sockaddr_ax25 *);
471extern const struct seq_operations ax25_uid_seqops;
472void ax25_uid_free(void);
473
474/* sysctl_net_ax25.c */
475#ifdef CONFIG_SYSCTL
476int ax25_register_dev_sysctl(ax25_dev *ax25_dev);
477void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev);
478#else
479static inline int ax25_register_dev_sysctl(ax25_dev *ax25_dev) { return 0; }
480static inline void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev) {}
481#endif /* CONFIG_SYSCTL */
482
483#endif
484