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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
6 * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk)
7 */
8#include <linux/module.h>
9#include <linux/moduleparam.h>
10#include <linux/capability.h>
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/socket.h>
14#include <linux/in.h>
15#include <linux/slab.h>
16#include <linux/kernel.h>
17#include <linux/sched/signal.h>
18#include <linux/timer.h>
19#include <linux/string.h>
20#include <linux/sockios.h>
21#include <linux/net.h>
22#include <linux/stat.h>
23#include <net/ax25.h>
24#include <linux/inet.h>
25#include <linux/netdevice.h>
26#include <linux/if_arp.h>
27#include <linux/skbuff.h>
28#include <net/net_namespace.h>
29#include <net/sock.h>
30#include <linux/uaccess.h>
31#include <linux/fcntl.h>
32#include <linux/termios.h> /* For TIOCINQ/OUTQ */
33#include <linux/mm.h>
34#include <linux/interrupt.h>
35#include <linux/notifier.h>
36#include <net/netrom.h>
37#include <linux/proc_fs.h>
38#include <linux/seq_file.h>
39#include <net/ip.h>
40#include <net/tcp_states.h>
41#include <net/arp.h>
42#include <linux/init.h>
43
44static int nr_ndevs = 4;
45
46int sysctl_netrom_default_path_quality = NR_DEFAULT_QUAL;
47int sysctl_netrom_obsolescence_count_initialiser = NR_DEFAULT_OBS;
48int sysctl_netrom_network_ttl_initialiser = NR_DEFAULT_TTL;
49int sysctl_netrom_transport_timeout = NR_DEFAULT_T1;
50int sysctl_netrom_transport_maximum_tries = NR_DEFAULT_N2;
51int sysctl_netrom_transport_acknowledge_delay = NR_DEFAULT_T2;
52int sysctl_netrom_transport_busy_delay = NR_DEFAULT_T4;
53int sysctl_netrom_transport_requested_window_size = NR_DEFAULT_WINDOW;
54int sysctl_netrom_transport_no_activity_timeout = NR_DEFAULT_IDLE;
55int sysctl_netrom_routing_control = NR_DEFAULT_ROUTING;
56int sysctl_netrom_link_fails_count = NR_DEFAULT_FAILS;
57int sysctl_netrom_reset_circuit = NR_DEFAULT_RESET;
58
59static unsigned short circuit = 0x101;
60
61static HLIST_HEAD(nr_list);
62static DEFINE_SPINLOCK(nr_list_lock);
63
64static const struct proto_ops nr_proto_ops;
65
66/*
67 * Socket removal during an interrupt is now safe.
68 */
69static void nr_remove_socket(struct sock *sk)
70{
71 spin_lock_bh(&nr_list_lock);
72 sk_del_node_init(sk);
73 spin_unlock_bh(&nr_list_lock);
74}
75
76/*
77 * Kill all bound sockets on a dropped device.
78 */
79static void nr_kill_by_device(struct net_device *dev)
80{
81 struct sock *s;
82
83 spin_lock_bh(&nr_list_lock);
84 sk_for_each(s, &nr_list)
85 if (nr_sk(s)->device == dev)
86 nr_disconnect(s, ENETUNREACH);
87 spin_unlock_bh(&nr_list_lock);
88}
89
90/*
91 * Handle device status changes.
92 */
93static int nr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
94{
95 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
96
97 if (!net_eq(dev_net(dev), &init_net))
98 return NOTIFY_DONE;
99
100 if (event != NETDEV_DOWN)
101 return NOTIFY_DONE;
102
103 nr_kill_by_device(dev);
104 nr_rt_device_down(dev);
105
106 return NOTIFY_DONE;
107}
108
109/*
110 * Add a socket to the bound sockets list.
111 */
112static void nr_insert_socket(struct sock *sk)
113{
114 spin_lock_bh(&nr_list_lock);
115 sk_add_node(sk, &nr_list);
116 spin_unlock_bh(&nr_list_lock);
117}
118
119/*
120 * Find a socket that wants to accept the Connect Request we just
121 * received.
122 */
123static struct sock *nr_find_listener(ax25_address *addr)
124{
125 struct sock *s;
126
127 spin_lock_bh(&nr_list_lock);
128 sk_for_each(s, &nr_list)
129 if (!ax25cmp(&nr_sk(s)->source_addr, addr) &&
130 s->sk_state == TCP_LISTEN) {
131 sock_hold(s);
132 goto found;
133 }
134 s = NULL;
135found:
136 spin_unlock_bh(&nr_list_lock);
137 return s;
138}
139
140/*
141 * Find a connected NET/ROM socket given my circuit IDs.
142 */
143static struct sock *nr_find_socket(unsigned char index, unsigned char id)
144{
145 struct sock *s;
146
147 spin_lock_bh(&nr_list_lock);
148 sk_for_each(s, &nr_list) {
149 struct nr_sock *nr = nr_sk(s);
150
151 if (nr->my_index == index && nr->my_id == id) {
152 sock_hold(s);
153 goto found;
154 }
155 }
156 s = NULL;
157found:
158 spin_unlock_bh(&nr_list_lock);
159 return s;
160}
161
162/*
163 * Find a connected NET/ROM socket given their circuit IDs.
164 */
165static struct sock *nr_find_peer(unsigned char index, unsigned char id,
166 ax25_address *dest)
167{
168 struct sock *s;
169
170 spin_lock_bh(&nr_list_lock);
171 sk_for_each(s, &nr_list) {
172 struct nr_sock *nr = nr_sk(s);
173
174 if (nr->your_index == index && nr->your_id == id &&
175 !ax25cmp(&nr->dest_addr, dest)) {
176 sock_hold(s);
177 goto found;
178 }
179 }
180 s = NULL;
181found:
182 spin_unlock_bh(&nr_list_lock);
183 return s;
184}
185
186/*
187 * Find next free circuit ID.
188 */
189static unsigned short nr_find_next_circuit(void)
190{
191 unsigned short id = circuit;
192 unsigned char i, j;
193 struct sock *sk;
194
195 for (;;) {
196 i = id / 256;
197 j = id % 256;
198
199 if (i != 0 && j != 0) {
200 if ((sk=nr_find_socket(i, j)) == NULL)
201 break;
202 sock_put(sk);
203 }
204
205 id++;
206 }
207
208 return id;
209}
210
211/*
212 * Deferred destroy.
213 */
214void nr_destroy_socket(struct sock *);
215
216/*
217 * Handler for deferred kills.
218 */
219static void nr_destroy_timer(struct timer_list *t)
220{
221 struct sock *sk = from_timer(sk, t, sk_timer);
222 bh_lock_sock(sk);
223 sock_hold(sk);
224 nr_destroy_socket(sk);
225 bh_unlock_sock(sk);
226 sock_put(sk);
227}
228
229/*
230 * This is called from user mode and the timers. Thus it protects itself
231 * against interrupt users but doesn't worry about being called during
232 * work. Once it is removed from the queue no interrupt or bottom half
233 * will touch it and we are (fairly 8-) ) safe.
234 */
235void nr_destroy_socket(struct sock *sk)
236{
237 struct sk_buff *skb;
238
239 nr_remove_socket(sk);
240
241 nr_stop_heartbeat(sk);
242 nr_stop_t1timer(sk);
243 nr_stop_t2timer(sk);
244 nr_stop_t4timer(sk);
245 nr_stop_idletimer(sk);
246
247 nr_clear_queues(sk); /* Flush the queues */
248
249 while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
250 if (skb->sk != sk) { /* A pending connection */
251 /* Queue the unaccepted socket for death */
252 sock_set_flag(skb->sk, SOCK_DEAD);
253 nr_start_heartbeat(skb->sk);
254 nr_sk(skb->sk)->state = NR_STATE_0;
255 }
256
257 kfree_skb(skb);
258 }
259
260 if (sk_has_allocations(sk)) {
261 /* Defer: outstanding buffers */
262 sk->sk_timer.function = nr_destroy_timer;
263 sk->sk_timer.expires = jiffies + 2 * HZ;
264 add_timer(&sk->sk_timer);
265 } else
266 sock_put(sk);
267}
268
269/*
270 * Handling for system calls applied via the various interfaces to a
271 * NET/ROM socket object.
272 */
273
274static int nr_setsockopt(struct socket *sock, int level, int optname,
275 char __user *optval, unsigned int optlen)
276{
277 struct sock *sk = sock->sk;
278 struct nr_sock *nr = nr_sk(sk);
279 unsigned long opt;
280
281 if (level != SOL_NETROM)
282 return -ENOPROTOOPT;
283
284 if (optlen < sizeof(unsigned int))
285 return -EINVAL;
286
287 if (get_user(opt, (unsigned int __user *)optval))
288 return -EFAULT;
289
290 switch (optname) {
291 case NETROM_T1:
292 if (opt < 1 || opt > ULONG_MAX / HZ)
293 return -EINVAL;
294 nr->t1 = opt * HZ;
295 return 0;
296
297 case NETROM_T2:
298 if (opt < 1 || opt > ULONG_MAX / HZ)
299 return -EINVAL;
300 nr->t2 = opt * HZ;
301 return 0;
302
303 case NETROM_N2:
304 if (opt < 1 || opt > 31)
305 return -EINVAL;
306 nr->n2 = opt;
307 return 0;
308
309 case NETROM_T4:
310 if (opt < 1 || opt > ULONG_MAX / HZ)
311 return -EINVAL;
312 nr->t4 = opt * HZ;
313 return 0;
314
315 case NETROM_IDLE:
316 if (opt > ULONG_MAX / (60 * HZ))
317 return -EINVAL;
318 nr->idle = opt * 60 * HZ;
319 return 0;
320
321 default:
322 return -ENOPROTOOPT;
323 }
324}
325
326static int nr_getsockopt(struct socket *sock, int level, int optname,
327 char __user *optval, int __user *optlen)
328{
329 struct sock *sk = sock->sk;
330 struct nr_sock *nr = nr_sk(sk);
331 int val = 0;
332 int len;
333
334 if (level != SOL_NETROM)
335 return -ENOPROTOOPT;
336
337 if (get_user(len, optlen))
338 return -EFAULT;
339
340 if (len < 0)
341 return -EINVAL;
342
343 switch (optname) {
344 case NETROM_T1:
345 val = nr->t1 / HZ;
346 break;
347
348 case NETROM_T2:
349 val = nr->t2 / HZ;
350 break;
351
352 case NETROM_N2:
353 val = nr->n2;
354 break;
355
356 case NETROM_T4:
357 val = nr->t4 / HZ;
358 break;
359
360 case NETROM_IDLE:
361 val = nr->idle / (60 * HZ);
362 break;
363
364 default:
365 return -ENOPROTOOPT;
366 }
367
368 len = min_t(unsigned int, len, sizeof(int));
369
370 if (put_user(len, optlen))
371 return -EFAULT;
372
373 return copy_to_user(optval, &val, len) ? -EFAULT : 0;
374}
375
376static int nr_listen(struct socket *sock, int backlog)
377{
378 struct sock *sk = sock->sk;
379
380 lock_sock(sk);
381 if (sk->sk_state != TCP_LISTEN) {
382 memset(&nr_sk(sk)->user_addr, 0, AX25_ADDR_LEN);
383 sk->sk_max_ack_backlog = backlog;
384 sk->sk_state = TCP_LISTEN;
385 release_sock(sk);
386 return 0;
387 }
388 release_sock(sk);
389
390 return -EOPNOTSUPP;
391}
392
393static struct proto nr_proto = {
394 .name = "NETROM",
395 .owner = THIS_MODULE,
396 .obj_size = sizeof(struct nr_sock),
397};
398
399static int nr_create(struct net *net, struct socket *sock, int protocol,
400 int kern)
401{
402 struct sock *sk;
403 struct nr_sock *nr;
404
405 if (!net_eq(net, &init_net))
406 return -EAFNOSUPPORT;
407
408 if (sock->type != SOCK_SEQPACKET || protocol != 0)
409 return -ESOCKTNOSUPPORT;
410
411 sk = sk_alloc(net, PF_NETROM, GFP_ATOMIC, &nr_proto, kern);
412 if (sk == NULL)
413 return -ENOMEM;
414
415 nr = nr_sk(sk);
416
417 sock_init_data(sock, sk);
418
419 sock->ops = &nr_proto_ops;
420 sk->sk_protocol = protocol;
421
422 skb_queue_head_init(&nr->ack_queue);
423 skb_queue_head_init(&nr->reseq_queue);
424 skb_queue_head_init(&nr->frag_queue);
425
426 nr_init_timers(sk);
427
428 nr->t1 =
429 msecs_to_jiffies(sysctl_netrom_transport_timeout);
430 nr->t2 =
431 msecs_to_jiffies(sysctl_netrom_transport_acknowledge_delay);
432 nr->n2 =
433 msecs_to_jiffies(sysctl_netrom_transport_maximum_tries);
434 nr->t4 =
435 msecs_to_jiffies(sysctl_netrom_transport_busy_delay);
436 nr->idle =
437 msecs_to_jiffies(sysctl_netrom_transport_no_activity_timeout);
438 nr->window = sysctl_netrom_transport_requested_window_size;
439
440 nr->bpqext = 1;
441 nr->state = NR_STATE_0;
442
443 return 0;
444}
445
446static struct sock *nr_make_new(struct sock *osk)
447{
448 struct sock *sk;
449 struct nr_sock *nr, *onr;
450
451 if (osk->sk_type != SOCK_SEQPACKET)
452 return NULL;
453
454 sk = sk_alloc(sock_net(osk), PF_NETROM, GFP_ATOMIC, osk->sk_prot, 0);
455 if (sk == NULL)
456 return NULL;
457
458 nr = nr_sk(sk);
459
460 sock_init_data(NULL, sk);
461
462 sk->sk_type = osk->sk_type;
463 sk->sk_priority = osk->sk_priority;
464 sk->sk_protocol = osk->sk_protocol;
465 sk->sk_rcvbuf = osk->sk_rcvbuf;
466 sk->sk_sndbuf = osk->sk_sndbuf;
467 sk->sk_state = TCP_ESTABLISHED;
468 sock_copy_flags(sk, osk);
469
470 skb_queue_head_init(&nr->ack_queue);
471 skb_queue_head_init(&nr->reseq_queue);
472 skb_queue_head_init(&nr->frag_queue);
473
474 nr_init_timers(sk);
475
476 onr = nr_sk(osk);
477
478 nr->t1 = onr->t1;
479 nr->t2 = onr->t2;
480 nr->n2 = onr->n2;
481 nr->t4 = onr->t4;
482 nr->idle = onr->idle;
483 nr->window = onr->window;
484
485 nr->device = onr->device;
486 nr->bpqext = onr->bpqext;
487
488 return sk;
489}
490
491static int nr_release(struct socket *sock)
492{
493 struct sock *sk = sock->sk;
494 struct nr_sock *nr;
495
496 if (sk == NULL) return 0;
497
498 sock_hold(sk);
499 sock_orphan(sk);
500 lock_sock(sk);
501 nr = nr_sk(sk);
502
503 switch (nr->state) {
504 case NR_STATE_0:
505 case NR_STATE_1:
506 case NR_STATE_2:
507 nr_disconnect(sk, 0);
508 nr_destroy_socket(sk);
509 break;
510
511 case NR_STATE_3:
512 nr_clear_queues(sk);
513 nr->n2count = 0;
514 nr_write_internal(sk, NR_DISCREQ);
515 nr_start_t1timer(sk);
516 nr_stop_t2timer(sk);
517 nr_stop_t4timer(sk);
518 nr_stop_idletimer(sk);
519 nr->state = NR_STATE_2;
520 sk->sk_state = TCP_CLOSE;
521 sk->sk_shutdown |= SEND_SHUTDOWN;
522 sk->sk_state_change(sk);
523 sock_set_flag(sk, SOCK_DESTROY);
524 break;
525
526 default:
527 break;
528 }
529
530 sock->sk = NULL;
531 release_sock(sk);
532 sock_put(sk);
533
534 return 0;
535}
536
537static int nr_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
538{
539 struct sock *sk = sock->sk;
540 struct nr_sock *nr = nr_sk(sk);
541 struct full_sockaddr_ax25 *addr = (struct full_sockaddr_ax25 *)uaddr;
542 struct net_device *dev;
543 ax25_uid_assoc *user;
544 ax25_address *source;
545
546 lock_sock(sk);
547 if (!sock_flag(sk, SOCK_ZAPPED)) {
548 release_sock(sk);
549 return -EINVAL;
550 }
551 if (addr_len < sizeof(struct sockaddr_ax25) || addr_len > sizeof(struct full_sockaddr_ax25)) {
552 release_sock(sk);
553 return -EINVAL;
554 }
555 if (addr_len < (addr->fsa_ax25.sax25_ndigis * sizeof(ax25_address) + sizeof(struct sockaddr_ax25))) {
556 release_sock(sk);
557 return -EINVAL;
558 }
559 if (addr->fsa_ax25.sax25_family != AF_NETROM) {
560 release_sock(sk);
561 return -EINVAL;
562 }
563 if ((dev = nr_dev_get(&addr->fsa_ax25.sax25_call)) == NULL) {
564 release_sock(sk);
565 return -EADDRNOTAVAIL;
566 }
567
568 /*
569 * Only the super user can set an arbitrary user callsign.
570 */
571 if (addr->fsa_ax25.sax25_ndigis == 1) {
572 if (!capable(CAP_NET_BIND_SERVICE)) {
573 dev_put(dev);
574 release_sock(sk);
575 return -EPERM;
576 }
577 nr->user_addr = addr->fsa_digipeater[0];
578 nr->source_addr = addr->fsa_ax25.sax25_call;
579 } else {
580 source = &addr->fsa_ax25.sax25_call;
581
582 user = ax25_findbyuid(current_euid());
583 if (user) {
584 nr->user_addr = user->call;
585 ax25_uid_put(user);
586 } else {
587 if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE)) {
588 release_sock(sk);
589 dev_put(dev);
590 return -EPERM;
591 }
592 nr->user_addr = *source;
593 }
594
595 nr->source_addr = *source;
596 }
597
598 nr->device = dev;
599 nr_insert_socket(sk);
600
601 sock_reset_flag(sk, SOCK_ZAPPED);
602 dev_put(dev);
603 release_sock(sk);
604
605 return 0;
606}
607
608static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
609 int addr_len, int flags)
610{
611 struct sock *sk = sock->sk;
612 struct nr_sock *nr = nr_sk(sk);
613 struct sockaddr_ax25 *addr = (struct sockaddr_ax25 *)uaddr;
614 ax25_address *source = NULL;
615 ax25_uid_assoc *user;
616 struct net_device *dev;
617 int err = 0;
618
619 lock_sock(sk);
620 if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
621 sock->state = SS_CONNECTED;
622 goto out_release; /* Connect completed during a ERESTARTSYS event */
623 }
624
625 if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
626 sock->state = SS_UNCONNECTED;
627 err = -ECONNREFUSED;
628 goto out_release;
629 }
630
631 if (sk->sk_state == TCP_ESTABLISHED) {
632 err = -EISCONN; /* No reconnect on a seqpacket socket */
633 goto out_release;
634 }
635
636 sk->sk_state = TCP_CLOSE;
637 sock->state = SS_UNCONNECTED;
638
639 if (addr_len != sizeof(struct sockaddr_ax25) && addr_len != sizeof(struct full_sockaddr_ax25)) {
640 err = -EINVAL;
641 goto out_release;
642 }
643 if (addr->sax25_family != AF_NETROM) {
644 err = -EINVAL;
645 goto out_release;
646 }
647 if (sock_flag(sk, SOCK_ZAPPED)) { /* Must bind first - autobinding in this may or may not work */
648 sock_reset_flag(sk, SOCK_ZAPPED);
649
650 if ((dev = nr_dev_first()) == NULL) {
651 err = -ENETUNREACH;
652 goto out_release;
653 }
654 source = (ax25_address *)dev->dev_addr;
655
656 user = ax25_findbyuid(current_euid());
657 if (user) {
658 nr->user_addr = user->call;
659 ax25_uid_put(user);
660 } else {
661 if (ax25_uid_policy && !capable(CAP_NET_ADMIN)) {
662 dev_put(dev);
663 err = -EPERM;
664 goto out_release;
665 }
666 nr->user_addr = *source;
667 }
668
669 nr->source_addr = *source;
670 nr->device = dev;
671
672 dev_put(dev);
673 nr_insert_socket(sk); /* Finish the bind */
674 }
675
676 nr->dest_addr = addr->sax25_call;
677
678 release_sock(sk);
679 circuit = nr_find_next_circuit();
680 lock_sock(sk);
681
682 nr->my_index = circuit / 256;
683 nr->my_id = circuit % 256;
684
685 circuit++;
686
687 /* Move to connecting socket, start sending Connect Requests */
688 sock->state = SS_CONNECTING;
689 sk->sk_state = TCP_SYN_SENT;
690
691 nr_establish_data_link(sk);
692
693 nr->state = NR_STATE_1;
694
695 nr_start_heartbeat(sk);
696
697 /* Now the loop */
698 if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
699 err = -EINPROGRESS;
700 goto out_release;
701 }
702
703 /*
704 * A Connect Ack with Choke or timeout or failed routing will go to
705 * closed.
706 */
707 if (sk->sk_state == TCP_SYN_SENT) {
708 DEFINE_WAIT(wait);
709
710 for (;;) {
711 prepare_to_wait(sk_sleep(sk), &wait,
712 TASK_INTERRUPTIBLE);
713 if (sk->sk_state != TCP_SYN_SENT)
714 break;
715 if (!signal_pending(current)) {
716 release_sock(sk);
717 schedule();
718 lock_sock(sk);
719 continue;
720 }
721 err = -ERESTARTSYS;
722 break;
723 }
724 finish_wait(sk_sleep(sk), &wait);
725 if (err)
726 goto out_release;
727 }
728
729 if (sk->sk_state != TCP_ESTABLISHED) {
730 sock->state = SS_UNCONNECTED;
731 err = sock_error(sk); /* Always set at this point */
732 goto out_release;
733 }
734
735 sock->state = SS_CONNECTED;
736
737out_release:
738 release_sock(sk);
739
740 return err;
741}
742
743static int nr_accept(struct socket *sock, struct socket *newsock, int flags,
744 bool kern)
745{
746 struct sk_buff *skb;
747 struct sock *newsk;
748 DEFINE_WAIT(wait);
749 struct sock *sk;
750 int err = 0;
751
752 if ((sk = sock->sk) == NULL)
753 return -EINVAL;
754
755 lock_sock(sk);
756 if (sk->sk_type != SOCK_SEQPACKET) {
757 err = -EOPNOTSUPP;
758 goto out_release;
759 }
760
761 if (sk->sk_state != TCP_LISTEN) {
762 err = -EINVAL;
763 goto out_release;
764 }
765
766 /*
767 * The write queue this time is holding sockets ready to use
768 * hooked into the SABM we saved
769 */
770 for (;;) {
771 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
772 skb = skb_dequeue(&sk->sk_receive_queue);
773 if (skb)
774 break;
775
776 if (flags & O_NONBLOCK) {
777 err = -EWOULDBLOCK;
778 break;
779 }
780 if (!signal_pending(current)) {
781 release_sock(sk);
782 schedule();
783 lock_sock(sk);
784 continue;
785 }
786 err = -ERESTARTSYS;
787 break;
788 }
789 finish_wait(sk_sleep(sk), &wait);
790 if (err)
791 goto out_release;
792
793 newsk = skb->sk;
794 sock_graft(newsk, newsock);
795
796 /* Now attach up the new socket */
797 kfree_skb(skb);
798 sk_acceptq_removed(sk);
799
800out_release:
801 release_sock(sk);
802
803 return err;
804}
805
806static int nr_getname(struct socket *sock, struct sockaddr *uaddr,
807 int peer)
808{
809 struct full_sockaddr_ax25 *sax = (struct full_sockaddr_ax25 *)uaddr;
810 struct sock *sk = sock->sk;
811 struct nr_sock *nr = nr_sk(sk);
812 int uaddr_len;
813
814 memset(&sax->fsa_ax25, 0, sizeof(struct sockaddr_ax25));
815
816 lock_sock(sk);
817 if (peer != 0) {
818 if (sk->sk_state != TCP_ESTABLISHED) {
819 release_sock(sk);
820 return -ENOTCONN;
821 }
822 sax->fsa_ax25.sax25_family = AF_NETROM;
823 sax->fsa_ax25.sax25_ndigis = 1;
824 sax->fsa_ax25.sax25_call = nr->user_addr;
825 memset(sax->fsa_digipeater, 0, sizeof(sax->fsa_digipeater));
826 sax->fsa_digipeater[0] = nr->dest_addr;
827 uaddr_len = sizeof(struct full_sockaddr_ax25);
828 } else {
829 sax->fsa_ax25.sax25_family = AF_NETROM;
830 sax->fsa_ax25.sax25_ndigis = 0;
831 sax->fsa_ax25.sax25_call = nr->source_addr;
832 uaddr_len = sizeof(struct sockaddr_ax25);
833 }
834 release_sock(sk);
835
836 return uaddr_len;
837}
838
839int nr_rx_frame(struct sk_buff *skb, struct net_device *dev)
840{
841 struct sock *sk;
842 struct sock *make;
843 struct nr_sock *nr_make;
844 ax25_address *src, *dest, *user;
845 unsigned short circuit_index, circuit_id;
846 unsigned short peer_circuit_index, peer_circuit_id;
847 unsigned short frametype, flags, window, timeout;
848 int ret;
849
850 skb_orphan(skb);
851
852 /*
853 * skb->data points to the netrom frame start
854 */
855
856 src = (ax25_address *)(skb->data + 0);
857 dest = (ax25_address *)(skb->data + 7);
858
859 circuit_index = skb->data[15];
860 circuit_id = skb->data[16];
861 peer_circuit_index = skb->data[17];
862 peer_circuit_id = skb->data[18];
863 frametype = skb->data[19] & 0x0F;
864 flags = skb->data[19] & 0xF0;
865
866 /*
867 * Check for an incoming IP over NET/ROM frame.
868 */
869 if (frametype == NR_PROTOEXT &&
870 circuit_index == NR_PROTO_IP && circuit_id == NR_PROTO_IP) {
871 skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
872 skb_reset_transport_header(skb);
873
874 return nr_rx_ip(skb, dev);
875 }
876
877 /*
878 * Find an existing socket connection, based on circuit ID, if it's
879 * a Connect Request base it on their circuit ID.
880 *
881 * Circuit ID 0/0 is not valid but it could still be a "reset" for a
882 * circuit that no longer exists at the other end ...
883 */
884
885 sk = NULL;
886
887 if (circuit_index == 0 && circuit_id == 0) {
888 if (frametype == NR_CONNACK && flags == NR_CHOKE_FLAG)
889 sk = nr_find_peer(peer_circuit_index, peer_circuit_id, src);
890 } else {
891 if (frametype == NR_CONNREQ)
892 sk = nr_find_peer(circuit_index, circuit_id, src);
893 else
894 sk = nr_find_socket(circuit_index, circuit_id);
895 }
896
897 if (sk != NULL) {
898 bh_lock_sock(sk);
899 skb_reset_transport_header(skb);
900
901 if (frametype == NR_CONNACK && skb->len == 22)
902 nr_sk(sk)->bpqext = 1;
903 else
904 nr_sk(sk)->bpqext = 0;
905
906 ret = nr_process_rx_frame(sk, skb);
907 bh_unlock_sock(sk);
908 sock_put(sk);
909 return ret;
910 }
911
912 /*
913 * Now it should be a CONNREQ.
914 */
915 if (frametype != NR_CONNREQ) {
916 /*
917 * Here it would be nice to be able to send a reset but
918 * NET/ROM doesn't have one. We've tried to extend the protocol
919 * by sending NR_CONNACK | NR_CHOKE_FLAGS replies but that
920 * apparently kills BPQ boxes... :-(
921 * So now we try to follow the established behaviour of
922 * G8PZT's Xrouter which is sending packets with command type 7
923 * as an extension of the protocol.
924 */
925 if (sysctl_netrom_reset_circuit &&
926 (frametype != NR_RESET || flags != 0))
927 nr_transmit_reset(skb, 1);
928
929 return 0;
930 }
931
932 sk = nr_find_listener(dest);
933
934 user = (ax25_address *)(skb->data + 21);
935
936 if (sk == NULL || sk_acceptq_is_full(sk) ||
937 (make = nr_make_new(sk)) == NULL) {
938 nr_transmit_refusal(skb, 0);
939 if (sk)
940 sock_put(sk);
941 return 0;
942 }
943
944 bh_lock_sock(sk);
945
946 window = skb->data[20];
947
948 sock_hold(make);
949 skb->sk = make;
950 skb->destructor = sock_efree;
951 make->sk_state = TCP_ESTABLISHED;
952
953 /* Fill in his circuit details */
954 nr_make = nr_sk(make);
955 nr_make->source_addr = *dest;
956 nr_make->dest_addr = *src;
957 nr_make->user_addr = *user;
958
959 nr_make->your_index = circuit_index;
960 nr_make->your_id = circuit_id;
961
962 bh_unlock_sock(sk);
963 circuit = nr_find_next_circuit();
964 bh_lock_sock(sk);
965
966 nr_make->my_index = circuit / 256;
967 nr_make->my_id = circuit % 256;
968
969 circuit++;
970
971 /* Window negotiation */
972 if (window < nr_make->window)
973 nr_make->window = window;
974
975 /* L4 timeout negotiation */
976 if (skb->len == 37) {
977 timeout = skb->data[36] * 256 + skb->data[35];
978 if (timeout * HZ < nr_make->t1)
979 nr_make->t1 = timeout * HZ;
980 nr_make->bpqext = 1;
981 } else {
982 nr_make->bpqext = 0;
983 }
984
985 nr_write_internal(make, NR_CONNACK);
986
987 nr_make->condition = 0x00;
988 nr_make->vs = 0;
989 nr_make->va = 0;
990 nr_make->vr = 0;
991 nr_make->vl = 0;
992 nr_make->state = NR_STATE_3;
993 sk_acceptq_added(sk);
994 skb_queue_head(&sk->sk_receive_queue, skb);
995
996 if (!sock_flag(sk, SOCK_DEAD))
997 sk->sk_data_ready(sk);
998
999 bh_unlock_sock(sk);
1000 sock_put(sk);
1001
1002 nr_insert_socket(make);
1003
1004 nr_start_heartbeat(make);
1005 nr_start_idletimer(make);
1006
1007 return 1;
1008}
1009
1010static int nr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1011{
1012 struct sock *sk = sock->sk;
1013 struct nr_sock *nr = nr_sk(sk);
1014 DECLARE_SOCKADDR(struct sockaddr_ax25 *, usax, msg->msg_name);
1015 int err;
1016 struct sockaddr_ax25 sax;
1017 struct sk_buff *skb;
1018 unsigned char *asmptr;
1019 int size;
1020
1021 if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_CMSG_COMPAT))
1022 return -EINVAL;
1023
1024 lock_sock(sk);
1025 if (sock_flag(sk, SOCK_ZAPPED)) {
1026 err = -EADDRNOTAVAIL;
1027 goto out;
1028 }
1029
1030 if (sk->sk_shutdown & SEND_SHUTDOWN) {
1031 send_sig(SIGPIPE, current, 0);
1032 err = -EPIPE;
1033 goto out;
1034 }
1035
1036 if (nr->device == NULL) {
1037 err = -ENETUNREACH;
1038 goto out;
1039 }
1040
1041 if (usax) {
1042 if (msg->msg_namelen < sizeof(sax)) {
1043 err = -EINVAL;
1044 goto out;
1045 }
1046 sax = *usax;
1047 if (ax25cmp(&nr->dest_addr, &sax.sax25_call) != 0) {
1048 err = -EISCONN;
1049 goto out;
1050 }
1051 if (sax.sax25_family != AF_NETROM) {
1052 err = -EINVAL;
1053 goto out;
1054 }
1055 } else {
1056 if (sk->sk_state != TCP_ESTABLISHED) {
1057 err = -ENOTCONN;
1058 goto out;
1059 }
1060 sax.sax25_family = AF_NETROM;
1061 sax.sax25_call = nr->dest_addr;
1062 }
1063
1064 /* Build a packet - the conventional user limit is 236 bytes. We can
1065 do ludicrously large NetROM frames but must not overflow */
1066 if (len > 65536) {
1067 err = -EMSGSIZE;
1068 goto out;
1069 }
1070
1071 size = len + NR_NETWORK_LEN + NR_TRANSPORT_LEN;
1072
1073 if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
1074 goto out;
1075
1076 skb_reserve(skb, size - len);
1077 skb_reset_transport_header(skb);
1078
1079 /*
1080 * Push down the NET/ROM header
1081 */
1082
1083 asmptr = skb_push(skb, NR_TRANSPORT_LEN);
1084
1085 /* Build a NET/ROM Transport header */
1086
1087 *asmptr++ = nr->your_index;
1088 *asmptr++ = nr->your_id;
1089 *asmptr++ = 0; /* To be filled in later */
1090 *asmptr++ = 0; /* Ditto */
1091 *asmptr++ = NR_INFO;
1092
1093 /*
1094 * Put the data on the end
1095 */
1096 skb_put(skb, len);
1097
1098 /* User data follows immediately after the NET/ROM transport header */
1099 if (memcpy_from_msg(skb_transport_header(skb), msg, len)) {
1100 kfree_skb(skb);
1101 err = -EFAULT;
1102 goto out;
1103 }
1104
1105 if (sk->sk_state != TCP_ESTABLISHED) {
1106 kfree_skb(skb);
1107 err = -ENOTCONN;
1108 goto out;
1109 }
1110
1111 nr_output(sk, skb); /* Shove it onto the queue */
1112
1113 err = len;
1114out:
1115 release_sock(sk);
1116 return err;
1117}
1118
1119static int nr_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1120 int flags)
1121{
1122 struct sock *sk = sock->sk;
1123 DECLARE_SOCKADDR(struct sockaddr_ax25 *, sax, msg->msg_name);
1124 size_t copied;
1125 struct sk_buff *skb;
1126 int er;
1127
1128 /*
1129 * This works for seqpacket too. The receiver has ordered the queue for
1130 * us! We do one quick check first though
1131 */
1132
1133 lock_sock(sk);
1134 if (sk->sk_state != TCP_ESTABLISHED) {
1135 release_sock(sk);
1136 return -ENOTCONN;
1137 }
1138
1139 /* Now we can treat all alike */
1140 if ((skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &er)) == NULL) {
1141 release_sock(sk);
1142 return er;
1143 }
1144
1145 skb_reset_transport_header(skb);
1146 copied = skb->len;
1147
1148 if (copied > size) {
1149 copied = size;
1150 msg->msg_flags |= MSG_TRUNC;
1151 }
1152
1153 er = skb_copy_datagram_msg(skb, 0, msg, copied);
1154 if (er < 0) {
1155 skb_free_datagram(sk, skb);
1156 release_sock(sk);
1157 return er;
1158 }
1159
1160 if (sax != NULL) {
1161 memset(sax, 0, sizeof(*sax));
1162 sax->sax25_family = AF_NETROM;
1163 skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
1164 AX25_ADDR_LEN);
1165 msg->msg_namelen = sizeof(*sax);
1166 }
1167
1168 skb_free_datagram(sk, skb);
1169
1170 release_sock(sk);
1171 return copied;
1172}
1173
1174
1175static int nr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1176{
1177 struct sock *sk = sock->sk;
1178 void __user *argp = (void __user *)arg;
1179
1180 switch (cmd) {
1181 case TIOCOUTQ: {
1182 long amount;
1183
1184 lock_sock(sk);
1185 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1186 if (amount < 0)
1187 amount = 0;
1188 release_sock(sk);
1189 return put_user(amount, (int __user *)argp);
1190 }
1191
1192 case TIOCINQ: {
1193 struct sk_buff *skb;
1194 long amount = 0L;
1195
1196 lock_sock(sk);
1197 /* These two are safe on a single CPU system as only user tasks fiddle here */
1198 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1199 amount = skb->len;
1200 release_sock(sk);
1201 return put_user(amount, (int __user *)argp);
1202 }
1203
1204 case SIOCGIFADDR:
1205 case SIOCSIFADDR:
1206 case SIOCGIFDSTADDR:
1207 case SIOCSIFDSTADDR:
1208 case SIOCGIFBRDADDR:
1209 case SIOCSIFBRDADDR:
1210 case SIOCGIFNETMASK:
1211 case SIOCSIFNETMASK:
1212 case SIOCGIFMETRIC:
1213 case SIOCSIFMETRIC:
1214 return -EINVAL;
1215
1216 case SIOCADDRT:
1217 case SIOCDELRT:
1218 case SIOCNRDECOBS:
1219 if (!capable(CAP_NET_ADMIN))
1220 return -EPERM;
1221 return nr_rt_ioctl(cmd, argp);
1222
1223 default:
1224 return -ENOIOCTLCMD;
1225 }
1226
1227 return 0;
1228}
1229
1230#ifdef CONFIG_PROC_FS
1231
1232static void *nr_info_start(struct seq_file *seq, loff_t *pos)
1233{
1234 spin_lock_bh(&nr_list_lock);
1235 return seq_hlist_start_head(&nr_list, *pos);
1236}
1237
1238static void *nr_info_next(struct seq_file *seq, void *v, loff_t *pos)
1239{
1240 return seq_hlist_next(v, &nr_list, pos);
1241}
1242
1243static void nr_info_stop(struct seq_file *seq, void *v)
1244{
1245 spin_unlock_bh(&nr_list_lock);
1246}
1247
1248static int nr_info_show(struct seq_file *seq, void *v)
1249{
1250 struct sock *s = sk_entry(v);
1251 struct net_device *dev;
1252 struct nr_sock *nr;
1253 const char *devname;
1254 char buf[11];
1255
1256 if (v == SEQ_START_TOKEN)
1257 seq_puts(seq,
1258"user_addr dest_node src_node dev my your st vs vr va t1 t2 t4 idle n2 wnd Snd-Q Rcv-Q inode\n");
1259
1260 else {
1261
1262 bh_lock_sock(s);
1263 nr = nr_sk(s);
1264
1265 if ((dev = nr->device) == NULL)
1266 devname = "???";
1267 else
1268 devname = dev->name;
1269
1270 seq_printf(seq, "%-9s ", ax2asc(buf, &nr->user_addr));
1271 seq_printf(seq, "%-9s ", ax2asc(buf, &nr->dest_addr));
1272 seq_printf(seq,
1273"%-9s %-3s %02X/%02X %02X/%02X %2d %3d %3d %3d %3lu/%03lu %2lu/%02lu %3lu/%03lu %3lu/%03lu %2d/%02d %3d %5d %5d %ld\n",
1274 ax2asc(buf, &nr->source_addr),
1275 devname,
1276 nr->my_index,
1277 nr->my_id,
1278 nr->your_index,
1279 nr->your_id,
1280 nr->state,
1281 nr->vs,
1282 nr->vr,
1283 nr->va,
1284 ax25_display_timer(&nr->t1timer) / HZ,
1285 nr->t1 / HZ,
1286 ax25_display_timer(&nr->t2timer) / HZ,
1287 nr->t2 / HZ,
1288 ax25_display_timer(&nr->t4timer) / HZ,
1289 nr->t4 / HZ,
1290 ax25_display_timer(&nr->idletimer) / (60 * HZ),
1291 nr->idle / (60 * HZ),
1292 nr->n2count,
1293 nr->n2,
1294 nr->window,
1295 sk_wmem_alloc_get(s),
1296 sk_rmem_alloc_get(s),
1297 s->sk_socket ? SOCK_INODE(s->sk_socket)->i_ino : 0L);
1298
1299 bh_unlock_sock(s);
1300 }
1301 return 0;
1302}
1303
1304static const struct seq_operations nr_info_seqops = {
1305 .start = nr_info_start,
1306 .next = nr_info_next,
1307 .stop = nr_info_stop,
1308 .show = nr_info_show,
1309};
1310#endif /* CONFIG_PROC_FS */
1311
1312static const struct net_proto_family nr_family_ops = {
1313 .family = PF_NETROM,
1314 .create = nr_create,
1315 .owner = THIS_MODULE,
1316};
1317
1318static const struct proto_ops nr_proto_ops = {
1319 .family = PF_NETROM,
1320 .owner = THIS_MODULE,
1321 .release = nr_release,
1322 .bind = nr_bind,
1323 .connect = nr_connect,
1324 .socketpair = sock_no_socketpair,
1325 .accept = nr_accept,
1326 .getname = nr_getname,
1327 .poll = datagram_poll,
1328 .ioctl = nr_ioctl,
1329 .gettstamp = sock_gettstamp,
1330 .listen = nr_listen,
1331 .shutdown = sock_no_shutdown,
1332 .setsockopt = nr_setsockopt,
1333 .getsockopt = nr_getsockopt,
1334 .sendmsg = nr_sendmsg,
1335 .recvmsg = nr_recvmsg,
1336 .mmap = sock_no_mmap,
1337 .sendpage = sock_no_sendpage,
1338};
1339
1340static struct notifier_block nr_dev_notifier = {
1341 .notifier_call = nr_device_event,
1342};
1343
1344static struct net_device **dev_nr;
1345
1346static struct ax25_protocol nr_pid = {
1347 .pid = AX25_P_NETROM,
1348 .func = nr_route_frame
1349};
1350
1351static struct ax25_linkfail nr_linkfail_notifier = {
1352 .func = nr_link_failed,
1353};
1354
1355static int __init nr_proto_init(void)
1356{
1357 int i;
1358 int rc = proto_register(&nr_proto, 0);
1359
1360 if (rc)
1361 return rc;
1362
1363 if (nr_ndevs > 0x7fffffff/sizeof(struct net_device *)) {
1364 pr_err("NET/ROM: %s - nr_ndevs parameter too large\n",
1365 __func__);
1366 rc = -EINVAL;
1367 goto unregister_proto;
1368 }
1369
1370 dev_nr = kcalloc(nr_ndevs, sizeof(struct net_device *), GFP_KERNEL);
1371 if (!dev_nr) {
1372 pr_err("NET/ROM: %s - unable to allocate device array\n",
1373 __func__);
1374 rc = -ENOMEM;
1375 goto unregister_proto;
1376 }
1377
1378 for (i = 0; i < nr_ndevs; i++) {
1379 char name[IFNAMSIZ];
1380 struct net_device *dev;
1381
1382 sprintf(name, "nr%d", i);
1383 dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, nr_setup);
1384 if (!dev) {
1385 rc = -ENOMEM;
1386 goto fail;
1387 }
1388
1389 dev->base_addr = i;
1390 rc = register_netdev(dev);
1391 if (rc) {
1392 free_netdev(dev);
1393 goto fail;
1394 }
1395 dev_nr[i] = dev;
1396 }
1397
1398 rc = sock_register(&nr_family_ops);
1399 if (rc)
1400 goto fail;
1401
1402 rc = register_netdevice_notifier(&nr_dev_notifier);
1403 if (rc)
1404 goto out_sock;
1405
1406 ax25_register_pid(&nr_pid);
1407 ax25_linkfail_register(&nr_linkfail_notifier);
1408
1409#ifdef CONFIG_SYSCTL
1410 rc = nr_register_sysctl();
1411 if (rc)
1412 goto out_sysctl;
1413#endif
1414
1415 nr_loopback_init();
1416
1417 rc = -ENOMEM;
1418 if (!proc_create_seq("nr", 0444, init_net.proc_net, &nr_info_seqops))
1419 goto proc_remove1;
1420 if (!proc_create_seq("nr_neigh", 0444, init_net.proc_net,
1421 &nr_neigh_seqops))
1422 goto proc_remove2;
1423 if (!proc_create_seq("nr_nodes", 0444, init_net.proc_net,
1424 &nr_node_seqops))
1425 goto proc_remove3;
1426
1427 return 0;
1428
1429proc_remove3:
1430 remove_proc_entry("nr_neigh", init_net.proc_net);
1431proc_remove2:
1432 remove_proc_entry("nr", init_net.proc_net);
1433proc_remove1:
1434
1435 nr_loopback_clear();
1436 nr_rt_free();
1437
1438#ifdef CONFIG_SYSCTL
1439 nr_unregister_sysctl();
1440out_sysctl:
1441#endif
1442 ax25_linkfail_release(&nr_linkfail_notifier);
1443 ax25_protocol_release(AX25_P_NETROM);
1444 unregister_netdevice_notifier(&nr_dev_notifier);
1445out_sock:
1446 sock_unregister(PF_NETROM);
1447fail:
1448 while (--i >= 0) {
1449 unregister_netdev(dev_nr[i]);
1450 free_netdev(dev_nr[i]);
1451 }
1452 kfree(dev_nr);
1453unregister_proto:
1454 proto_unregister(&nr_proto);
1455 return rc;
1456}
1457
1458module_init(nr_proto_init);
1459
1460module_param(nr_ndevs, int, 0);
1461MODULE_PARM_DESC(nr_ndevs, "number of NET/ROM devices");
1462
1463MODULE_AUTHOR("Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>");
1464MODULE_DESCRIPTION("The amateur radio NET/ROM network and transport layer protocol");
1465MODULE_LICENSE("GPL");
1466MODULE_ALIAS_NETPROTO(PF_NETROM);
1467
1468static void __exit nr_exit(void)
1469{
1470 int i;
1471
1472 remove_proc_entry("nr", init_net.proc_net);
1473 remove_proc_entry("nr_neigh", init_net.proc_net);
1474 remove_proc_entry("nr_nodes", init_net.proc_net);
1475 nr_loopback_clear();
1476
1477 nr_rt_free();
1478
1479#ifdef CONFIG_SYSCTL
1480 nr_unregister_sysctl();
1481#endif
1482
1483 ax25_linkfail_release(&nr_linkfail_notifier);
1484 ax25_protocol_release(AX25_P_NETROM);
1485
1486 unregister_netdevice_notifier(&nr_dev_notifier);
1487
1488 sock_unregister(PF_NETROM);
1489
1490 for (i = 0; i < nr_ndevs; i++) {
1491 struct net_device *dev = dev_nr[i];
1492 if (dev) {
1493 unregister_netdev(dev);
1494 free_netdev(dev);
1495 }
1496 }
1497
1498 kfree(dev_nr);
1499 proto_unregister(&nr_proto);
1500}
1501module_exit(nr_exit);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
6 * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk)
7 */
8#include <linux/module.h>
9#include <linux/moduleparam.h>
10#include <linux/capability.h>
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/socket.h>
14#include <linux/in.h>
15#include <linux/slab.h>
16#include <linux/kernel.h>
17#include <linux/sched/signal.h>
18#include <linux/timer.h>
19#include <linux/string.h>
20#include <linux/sockios.h>
21#include <linux/net.h>
22#include <linux/stat.h>
23#include <net/ax25.h>
24#include <linux/inet.h>
25#include <linux/netdevice.h>
26#include <linux/if_arp.h>
27#include <linux/skbuff.h>
28#include <net/net_namespace.h>
29#include <net/sock.h>
30#include <linux/uaccess.h>
31#include <linux/fcntl.h>
32#include <linux/termios.h> /* For TIOCINQ/OUTQ */
33#include <linux/mm.h>
34#include <linux/interrupt.h>
35#include <linux/notifier.h>
36#include <net/netrom.h>
37#include <linux/proc_fs.h>
38#include <linux/seq_file.h>
39#include <net/ip.h>
40#include <net/tcp_states.h>
41#include <net/arp.h>
42#include <linux/init.h>
43
44static int nr_ndevs = 4;
45
46int sysctl_netrom_default_path_quality = NR_DEFAULT_QUAL;
47int sysctl_netrom_obsolescence_count_initialiser = NR_DEFAULT_OBS;
48int sysctl_netrom_network_ttl_initialiser = NR_DEFAULT_TTL;
49int sysctl_netrom_transport_timeout = NR_DEFAULT_T1;
50int sysctl_netrom_transport_maximum_tries = NR_DEFAULT_N2;
51int sysctl_netrom_transport_acknowledge_delay = NR_DEFAULT_T2;
52int sysctl_netrom_transport_busy_delay = NR_DEFAULT_T4;
53int sysctl_netrom_transport_requested_window_size = NR_DEFAULT_WINDOW;
54int sysctl_netrom_transport_no_activity_timeout = NR_DEFAULT_IDLE;
55int sysctl_netrom_routing_control = NR_DEFAULT_ROUTING;
56int sysctl_netrom_link_fails_count = NR_DEFAULT_FAILS;
57int sysctl_netrom_reset_circuit = NR_DEFAULT_RESET;
58
59static unsigned short circuit = 0x101;
60
61static HLIST_HEAD(nr_list);
62static DEFINE_SPINLOCK(nr_list_lock);
63
64static const struct proto_ops nr_proto_ops;
65
66/*
67 * NETROM network devices are virtual network devices encapsulating NETROM
68 * frames into AX.25 which will be sent through an AX.25 device, so form a
69 * special "super class" of normal net devices; split their locks off into a
70 * separate class since they always nest.
71 */
72static struct lock_class_key nr_netdev_xmit_lock_key;
73static struct lock_class_key nr_netdev_addr_lock_key;
74
75static void nr_set_lockdep_one(struct net_device *dev,
76 struct netdev_queue *txq,
77 void *_unused)
78{
79 lockdep_set_class(&txq->_xmit_lock, &nr_netdev_xmit_lock_key);
80}
81
82static void nr_set_lockdep_key(struct net_device *dev)
83{
84 lockdep_set_class(&dev->addr_list_lock, &nr_netdev_addr_lock_key);
85 netdev_for_each_tx_queue(dev, nr_set_lockdep_one, NULL);
86}
87
88/*
89 * Socket removal during an interrupt is now safe.
90 */
91static void nr_remove_socket(struct sock *sk)
92{
93 spin_lock_bh(&nr_list_lock);
94 sk_del_node_init(sk);
95 spin_unlock_bh(&nr_list_lock);
96}
97
98/*
99 * Kill all bound sockets on a dropped device.
100 */
101static void nr_kill_by_device(struct net_device *dev)
102{
103 struct sock *s;
104
105 spin_lock_bh(&nr_list_lock);
106 sk_for_each(s, &nr_list)
107 if (nr_sk(s)->device == dev)
108 nr_disconnect(s, ENETUNREACH);
109 spin_unlock_bh(&nr_list_lock);
110}
111
112/*
113 * Handle device status changes.
114 */
115static int nr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
116{
117 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
118
119 if (!net_eq(dev_net(dev), &init_net))
120 return NOTIFY_DONE;
121
122 if (event != NETDEV_DOWN)
123 return NOTIFY_DONE;
124
125 nr_kill_by_device(dev);
126 nr_rt_device_down(dev);
127
128 return NOTIFY_DONE;
129}
130
131/*
132 * Add a socket to the bound sockets list.
133 */
134static void nr_insert_socket(struct sock *sk)
135{
136 spin_lock_bh(&nr_list_lock);
137 sk_add_node(sk, &nr_list);
138 spin_unlock_bh(&nr_list_lock);
139}
140
141/*
142 * Find a socket that wants to accept the Connect Request we just
143 * received.
144 */
145static struct sock *nr_find_listener(ax25_address *addr)
146{
147 struct sock *s;
148
149 spin_lock_bh(&nr_list_lock);
150 sk_for_each(s, &nr_list)
151 if (!ax25cmp(&nr_sk(s)->source_addr, addr) &&
152 s->sk_state == TCP_LISTEN) {
153 sock_hold(s);
154 goto found;
155 }
156 s = NULL;
157found:
158 spin_unlock_bh(&nr_list_lock);
159 return s;
160}
161
162/*
163 * Find a connected NET/ROM socket given my circuit IDs.
164 */
165static struct sock *nr_find_socket(unsigned char index, unsigned char id)
166{
167 struct sock *s;
168
169 spin_lock_bh(&nr_list_lock);
170 sk_for_each(s, &nr_list) {
171 struct nr_sock *nr = nr_sk(s);
172
173 if (nr->my_index == index && nr->my_id == id) {
174 sock_hold(s);
175 goto found;
176 }
177 }
178 s = NULL;
179found:
180 spin_unlock_bh(&nr_list_lock);
181 return s;
182}
183
184/*
185 * Find a connected NET/ROM socket given their circuit IDs.
186 */
187static struct sock *nr_find_peer(unsigned char index, unsigned char id,
188 ax25_address *dest)
189{
190 struct sock *s;
191
192 spin_lock_bh(&nr_list_lock);
193 sk_for_each(s, &nr_list) {
194 struct nr_sock *nr = nr_sk(s);
195
196 if (nr->your_index == index && nr->your_id == id &&
197 !ax25cmp(&nr->dest_addr, dest)) {
198 sock_hold(s);
199 goto found;
200 }
201 }
202 s = NULL;
203found:
204 spin_unlock_bh(&nr_list_lock);
205 return s;
206}
207
208/*
209 * Find next free circuit ID.
210 */
211static unsigned short nr_find_next_circuit(void)
212{
213 unsigned short id = circuit;
214 unsigned char i, j;
215 struct sock *sk;
216
217 for (;;) {
218 i = id / 256;
219 j = id % 256;
220
221 if (i != 0 && j != 0) {
222 if ((sk=nr_find_socket(i, j)) == NULL)
223 break;
224 sock_put(sk);
225 }
226
227 id++;
228 }
229
230 return id;
231}
232
233/*
234 * Deferred destroy.
235 */
236void nr_destroy_socket(struct sock *);
237
238/*
239 * Handler for deferred kills.
240 */
241static void nr_destroy_timer(struct timer_list *t)
242{
243 struct sock *sk = from_timer(sk, t, sk_timer);
244 bh_lock_sock(sk);
245 sock_hold(sk);
246 nr_destroy_socket(sk);
247 bh_unlock_sock(sk);
248 sock_put(sk);
249}
250
251/*
252 * This is called from user mode and the timers. Thus it protects itself
253 * against interrupt users but doesn't worry about being called during
254 * work. Once it is removed from the queue no interrupt or bottom half
255 * will touch it and we are (fairly 8-) ) safe.
256 */
257void nr_destroy_socket(struct sock *sk)
258{
259 struct sk_buff *skb;
260
261 nr_remove_socket(sk);
262
263 nr_stop_heartbeat(sk);
264 nr_stop_t1timer(sk);
265 nr_stop_t2timer(sk);
266 nr_stop_t4timer(sk);
267 nr_stop_idletimer(sk);
268
269 nr_clear_queues(sk); /* Flush the queues */
270
271 while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
272 if (skb->sk != sk) { /* A pending connection */
273 /* Queue the unaccepted socket for death */
274 sock_set_flag(skb->sk, SOCK_DEAD);
275 nr_start_heartbeat(skb->sk);
276 nr_sk(skb->sk)->state = NR_STATE_0;
277 }
278
279 kfree_skb(skb);
280 }
281
282 if (sk_has_allocations(sk)) {
283 /* Defer: outstanding buffers */
284 sk->sk_timer.function = nr_destroy_timer;
285 sk->sk_timer.expires = jiffies + 2 * HZ;
286 add_timer(&sk->sk_timer);
287 } else
288 sock_put(sk);
289}
290
291/*
292 * Handling for system calls applied via the various interfaces to a
293 * NET/ROM socket object.
294 */
295
296static int nr_setsockopt(struct socket *sock, int level, int optname,
297 sockptr_t optval, unsigned int optlen)
298{
299 struct sock *sk = sock->sk;
300 struct nr_sock *nr = nr_sk(sk);
301 unsigned long opt;
302
303 if (level != SOL_NETROM)
304 return -ENOPROTOOPT;
305
306 if (optlen < sizeof(unsigned int))
307 return -EINVAL;
308
309 if (copy_from_sockptr(&opt, optval, sizeof(unsigned int)))
310 return -EFAULT;
311
312 switch (optname) {
313 case NETROM_T1:
314 if (opt < 1 || opt > ULONG_MAX / HZ)
315 return -EINVAL;
316 nr->t1 = opt * HZ;
317 return 0;
318
319 case NETROM_T2:
320 if (opt < 1 || opt > ULONG_MAX / HZ)
321 return -EINVAL;
322 nr->t2 = opt * HZ;
323 return 0;
324
325 case NETROM_N2:
326 if (opt < 1 || opt > 31)
327 return -EINVAL;
328 nr->n2 = opt;
329 return 0;
330
331 case NETROM_T4:
332 if (opt < 1 || opt > ULONG_MAX / HZ)
333 return -EINVAL;
334 nr->t4 = opt * HZ;
335 return 0;
336
337 case NETROM_IDLE:
338 if (opt > ULONG_MAX / (60 * HZ))
339 return -EINVAL;
340 nr->idle = opt * 60 * HZ;
341 return 0;
342
343 default:
344 return -ENOPROTOOPT;
345 }
346}
347
348static int nr_getsockopt(struct socket *sock, int level, int optname,
349 char __user *optval, int __user *optlen)
350{
351 struct sock *sk = sock->sk;
352 struct nr_sock *nr = nr_sk(sk);
353 int val = 0;
354 int len;
355
356 if (level != SOL_NETROM)
357 return -ENOPROTOOPT;
358
359 if (get_user(len, optlen))
360 return -EFAULT;
361
362 if (len < 0)
363 return -EINVAL;
364
365 switch (optname) {
366 case NETROM_T1:
367 val = nr->t1 / HZ;
368 break;
369
370 case NETROM_T2:
371 val = nr->t2 / HZ;
372 break;
373
374 case NETROM_N2:
375 val = nr->n2;
376 break;
377
378 case NETROM_T4:
379 val = nr->t4 / HZ;
380 break;
381
382 case NETROM_IDLE:
383 val = nr->idle / (60 * HZ);
384 break;
385
386 default:
387 return -ENOPROTOOPT;
388 }
389
390 len = min_t(unsigned int, len, sizeof(int));
391
392 if (put_user(len, optlen))
393 return -EFAULT;
394
395 return copy_to_user(optval, &val, len) ? -EFAULT : 0;
396}
397
398static int nr_listen(struct socket *sock, int backlog)
399{
400 struct sock *sk = sock->sk;
401
402 lock_sock(sk);
403 if (sk->sk_state != TCP_LISTEN) {
404 memset(&nr_sk(sk)->user_addr, 0, AX25_ADDR_LEN);
405 sk->sk_max_ack_backlog = backlog;
406 sk->sk_state = TCP_LISTEN;
407 release_sock(sk);
408 return 0;
409 }
410 release_sock(sk);
411
412 return -EOPNOTSUPP;
413}
414
415static struct proto nr_proto = {
416 .name = "NETROM",
417 .owner = THIS_MODULE,
418 .obj_size = sizeof(struct nr_sock),
419};
420
421static int nr_create(struct net *net, struct socket *sock, int protocol,
422 int kern)
423{
424 struct sock *sk;
425 struct nr_sock *nr;
426
427 if (!net_eq(net, &init_net))
428 return -EAFNOSUPPORT;
429
430 if (sock->type != SOCK_SEQPACKET || protocol != 0)
431 return -ESOCKTNOSUPPORT;
432
433 sk = sk_alloc(net, PF_NETROM, GFP_ATOMIC, &nr_proto, kern);
434 if (sk == NULL)
435 return -ENOMEM;
436
437 nr = nr_sk(sk);
438
439 sock_init_data(sock, sk);
440
441 sock->ops = &nr_proto_ops;
442 sk->sk_protocol = protocol;
443
444 skb_queue_head_init(&nr->ack_queue);
445 skb_queue_head_init(&nr->reseq_queue);
446 skb_queue_head_init(&nr->frag_queue);
447
448 nr_init_timers(sk);
449
450 nr->t1 =
451 msecs_to_jiffies(sysctl_netrom_transport_timeout);
452 nr->t2 =
453 msecs_to_jiffies(sysctl_netrom_transport_acknowledge_delay);
454 nr->n2 =
455 msecs_to_jiffies(sysctl_netrom_transport_maximum_tries);
456 nr->t4 =
457 msecs_to_jiffies(sysctl_netrom_transport_busy_delay);
458 nr->idle =
459 msecs_to_jiffies(sysctl_netrom_transport_no_activity_timeout);
460 nr->window = sysctl_netrom_transport_requested_window_size;
461
462 nr->bpqext = 1;
463 nr->state = NR_STATE_0;
464
465 return 0;
466}
467
468static struct sock *nr_make_new(struct sock *osk)
469{
470 struct sock *sk;
471 struct nr_sock *nr, *onr;
472
473 if (osk->sk_type != SOCK_SEQPACKET)
474 return NULL;
475
476 sk = sk_alloc(sock_net(osk), PF_NETROM, GFP_ATOMIC, osk->sk_prot, 0);
477 if (sk == NULL)
478 return NULL;
479
480 nr = nr_sk(sk);
481
482 sock_init_data(NULL, sk);
483
484 sk->sk_type = osk->sk_type;
485 sk->sk_priority = osk->sk_priority;
486 sk->sk_protocol = osk->sk_protocol;
487 sk->sk_rcvbuf = osk->sk_rcvbuf;
488 sk->sk_sndbuf = osk->sk_sndbuf;
489 sk->sk_state = TCP_ESTABLISHED;
490 sock_copy_flags(sk, osk);
491
492 skb_queue_head_init(&nr->ack_queue);
493 skb_queue_head_init(&nr->reseq_queue);
494 skb_queue_head_init(&nr->frag_queue);
495
496 nr_init_timers(sk);
497
498 onr = nr_sk(osk);
499
500 nr->t1 = onr->t1;
501 nr->t2 = onr->t2;
502 nr->n2 = onr->n2;
503 nr->t4 = onr->t4;
504 nr->idle = onr->idle;
505 nr->window = onr->window;
506
507 nr->device = onr->device;
508 nr->bpqext = onr->bpqext;
509
510 return sk;
511}
512
513static int nr_release(struct socket *sock)
514{
515 struct sock *sk = sock->sk;
516 struct nr_sock *nr;
517
518 if (sk == NULL) return 0;
519
520 sock_hold(sk);
521 sock_orphan(sk);
522 lock_sock(sk);
523 nr = nr_sk(sk);
524
525 switch (nr->state) {
526 case NR_STATE_0:
527 case NR_STATE_1:
528 case NR_STATE_2:
529 nr_disconnect(sk, 0);
530 nr_destroy_socket(sk);
531 break;
532
533 case NR_STATE_3:
534 nr_clear_queues(sk);
535 nr->n2count = 0;
536 nr_write_internal(sk, NR_DISCREQ);
537 nr_start_t1timer(sk);
538 nr_stop_t2timer(sk);
539 nr_stop_t4timer(sk);
540 nr_stop_idletimer(sk);
541 nr->state = NR_STATE_2;
542 sk->sk_state = TCP_CLOSE;
543 sk->sk_shutdown |= SEND_SHUTDOWN;
544 sk->sk_state_change(sk);
545 sock_set_flag(sk, SOCK_DESTROY);
546 break;
547
548 default:
549 break;
550 }
551
552 sock->sk = NULL;
553 release_sock(sk);
554 sock_put(sk);
555
556 return 0;
557}
558
559static int nr_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
560{
561 struct sock *sk = sock->sk;
562 struct nr_sock *nr = nr_sk(sk);
563 struct full_sockaddr_ax25 *addr = (struct full_sockaddr_ax25 *)uaddr;
564 struct net_device *dev;
565 ax25_uid_assoc *user;
566 ax25_address *source;
567
568 lock_sock(sk);
569 if (!sock_flag(sk, SOCK_ZAPPED)) {
570 release_sock(sk);
571 return -EINVAL;
572 }
573 if (addr_len < sizeof(struct sockaddr_ax25) || addr_len > sizeof(struct full_sockaddr_ax25)) {
574 release_sock(sk);
575 return -EINVAL;
576 }
577 if (addr_len < (addr->fsa_ax25.sax25_ndigis * sizeof(ax25_address) + sizeof(struct sockaddr_ax25))) {
578 release_sock(sk);
579 return -EINVAL;
580 }
581 if (addr->fsa_ax25.sax25_family != AF_NETROM) {
582 release_sock(sk);
583 return -EINVAL;
584 }
585 if ((dev = nr_dev_get(&addr->fsa_ax25.sax25_call)) == NULL) {
586 release_sock(sk);
587 return -EADDRNOTAVAIL;
588 }
589
590 /*
591 * Only the super user can set an arbitrary user callsign.
592 */
593 if (addr->fsa_ax25.sax25_ndigis == 1) {
594 if (!capable(CAP_NET_BIND_SERVICE)) {
595 dev_put(dev);
596 release_sock(sk);
597 return -EPERM;
598 }
599 nr->user_addr = addr->fsa_digipeater[0];
600 nr->source_addr = addr->fsa_ax25.sax25_call;
601 } else {
602 source = &addr->fsa_ax25.sax25_call;
603
604 user = ax25_findbyuid(current_euid());
605 if (user) {
606 nr->user_addr = user->call;
607 ax25_uid_put(user);
608 } else {
609 if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE)) {
610 release_sock(sk);
611 dev_put(dev);
612 return -EPERM;
613 }
614 nr->user_addr = *source;
615 }
616
617 nr->source_addr = *source;
618 }
619
620 nr->device = dev;
621 nr_insert_socket(sk);
622
623 sock_reset_flag(sk, SOCK_ZAPPED);
624 dev_put(dev);
625 release_sock(sk);
626
627 return 0;
628}
629
630static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
631 int addr_len, int flags)
632{
633 struct sock *sk = sock->sk;
634 struct nr_sock *nr = nr_sk(sk);
635 struct sockaddr_ax25 *addr = (struct sockaddr_ax25 *)uaddr;
636 ax25_address *source = NULL;
637 ax25_uid_assoc *user;
638 struct net_device *dev;
639 int err = 0;
640
641 lock_sock(sk);
642 if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
643 sock->state = SS_CONNECTED;
644 goto out_release; /* Connect completed during a ERESTARTSYS event */
645 }
646
647 if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
648 sock->state = SS_UNCONNECTED;
649 err = -ECONNREFUSED;
650 goto out_release;
651 }
652
653 if (sk->sk_state == TCP_ESTABLISHED) {
654 err = -EISCONN; /* No reconnect on a seqpacket socket */
655 goto out_release;
656 }
657
658 sk->sk_state = TCP_CLOSE;
659 sock->state = SS_UNCONNECTED;
660
661 if (addr_len != sizeof(struct sockaddr_ax25) && addr_len != sizeof(struct full_sockaddr_ax25)) {
662 err = -EINVAL;
663 goto out_release;
664 }
665 if (addr->sax25_family != AF_NETROM) {
666 err = -EINVAL;
667 goto out_release;
668 }
669 if (sock_flag(sk, SOCK_ZAPPED)) { /* Must bind first - autobinding in this may or may not work */
670 sock_reset_flag(sk, SOCK_ZAPPED);
671
672 if ((dev = nr_dev_first()) == NULL) {
673 err = -ENETUNREACH;
674 goto out_release;
675 }
676 source = (ax25_address *)dev->dev_addr;
677
678 user = ax25_findbyuid(current_euid());
679 if (user) {
680 nr->user_addr = user->call;
681 ax25_uid_put(user);
682 } else {
683 if (ax25_uid_policy && !capable(CAP_NET_ADMIN)) {
684 dev_put(dev);
685 err = -EPERM;
686 goto out_release;
687 }
688 nr->user_addr = *source;
689 }
690
691 nr->source_addr = *source;
692 nr->device = dev;
693
694 dev_put(dev);
695 nr_insert_socket(sk); /* Finish the bind */
696 }
697
698 nr->dest_addr = addr->sax25_call;
699
700 release_sock(sk);
701 circuit = nr_find_next_circuit();
702 lock_sock(sk);
703
704 nr->my_index = circuit / 256;
705 nr->my_id = circuit % 256;
706
707 circuit++;
708
709 /* Move to connecting socket, start sending Connect Requests */
710 sock->state = SS_CONNECTING;
711 sk->sk_state = TCP_SYN_SENT;
712
713 nr_establish_data_link(sk);
714
715 nr->state = NR_STATE_1;
716
717 nr_start_heartbeat(sk);
718
719 /* Now the loop */
720 if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
721 err = -EINPROGRESS;
722 goto out_release;
723 }
724
725 /*
726 * A Connect Ack with Choke or timeout or failed routing will go to
727 * closed.
728 */
729 if (sk->sk_state == TCP_SYN_SENT) {
730 DEFINE_WAIT(wait);
731
732 for (;;) {
733 prepare_to_wait(sk_sleep(sk), &wait,
734 TASK_INTERRUPTIBLE);
735 if (sk->sk_state != TCP_SYN_SENT)
736 break;
737 if (!signal_pending(current)) {
738 release_sock(sk);
739 schedule();
740 lock_sock(sk);
741 continue;
742 }
743 err = -ERESTARTSYS;
744 break;
745 }
746 finish_wait(sk_sleep(sk), &wait);
747 if (err)
748 goto out_release;
749 }
750
751 if (sk->sk_state != TCP_ESTABLISHED) {
752 sock->state = SS_UNCONNECTED;
753 err = sock_error(sk); /* Always set at this point */
754 goto out_release;
755 }
756
757 sock->state = SS_CONNECTED;
758
759out_release:
760 release_sock(sk);
761
762 return err;
763}
764
765static int nr_accept(struct socket *sock, struct socket *newsock, int flags,
766 bool kern)
767{
768 struct sk_buff *skb;
769 struct sock *newsk;
770 DEFINE_WAIT(wait);
771 struct sock *sk;
772 int err = 0;
773
774 if ((sk = sock->sk) == NULL)
775 return -EINVAL;
776
777 lock_sock(sk);
778 if (sk->sk_type != SOCK_SEQPACKET) {
779 err = -EOPNOTSUPP;
780 goto out_release;
781 }
782
783 if (sk->sk_state != TCP_LISTEN) {
784 err = -EINVAL;
785 goto out_release;
786 }
787
788 /*
789 * The write queue this time is holding sockets ready to use
790 * hooked into the SABM we saved
791 */
792 for (;;) {
793 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
794 skb = skb_dequeue(&sk->sk_receive_queue);
795 if (skb)
796 break;
797
798 if (flags & O_NONBLOCK) {
799 err = -EWOULDBLOCK;
800 break;
801 }
802 if (!signal_pending(current)) {
803 release_sock(sk);
804 schedule();
805 lock_sock(sk);
806 continue;
807 }
808 err = -ERESTARTSYS;
809 break;
810 }
811 finish_wait(sk_sleep(sk), &wait);
812 if (err)
813 goto out_release;
814
815 newsk = skb->sk;
816 sock_graft(newsk, newsock);
817
818 /* Now attach up the new socket */
819 kfree_skb(skb);
820 sk_acceptq_removed(sk);
821
822out_release:
823 release_sock(sk);
824
825 return err;
826}
827
828static int nr_getname(struct socket *sock, struct sockaddr *uaddr,
829 int peer)
830{
831 struct full_sockaddr_ax25 *sax = (struct full_sockaddr_ax25 *)uaddr;
832 struct sock *sk = sock->sk;
833 struct nr_sock *nr = nr_sk(sk);
834 int uaddr_len;
835
836 memset(&sax->fsa_ax25, 0, sizeof(struct sockaddr_ax25));
837
838 lock_sock(sk);
839 if (peer != 0) {
840 if (sk->sk_state != TCP_ESTABLISHED) {
841 release_sock(sk);
842 return -ENOTCONN;
843 }
844 sax->fsa_ax25.sax25_family = AF_NETROM;
845 sax->fsa_ax25.sax25_ndigis = 1;
846 sax->fsa_ax25.sax25_call = nr->user_addr;
847 memset(sax->fsa_digipeater, 0, sizeof(sax->fsa_digipeater));
848 sax->fsa_digipeater[0] = nr->dest_addr;
849 uaddr_len = sizeof(struct full_sockaddr_ax25);
850 } else {
851 sax->fsa_ax25.sax25_family = AF_NETROM;
852 sax->fsa_ax25.sax25_ndigis = 0;
853 sax->fsa_ax25.sax25_call = nr->source_addr;
854 uaddr_len = sizeof(struct sockaddr_ax25);
855 }
856 release_sock(sk);
857
858 return uaddr_len;
859}
860
861int nr_rx_frame(struct sk_buff *skb, struct net_device *dev)
862{
863 struct sock *sk;
864 struct sock *make;
865 struct nr_sock *nr_make;
866 ax25_address *src, *dest, *user;
867 unsigned short circuit_index, circuit_id;
868 unsigned short peer_circuit_index, peer_circuit_id;
869 unsigned short frametype, flags, window, timeout;
870 int ret;
871
872 skb_orphan(skb);
873
874 /*
875 * skb->data points to the netrom frame start
876 */
877
878 src = (ax25_address *)(skb->data + 0);
879 dest = (ax25_address *)(skb->data + 7);
880
881 circuit_index = skb->data[15];
882 circuit_id = skb->data[16];
883 peer_circuit_index = skb->data[17];
884 peer_circuit_id = skb->data[18];
885 frametype = skb->data[19] & 0x0F;
886 flags = skb->data[19] & 0xF0;
887
888 /*
889 * Check for an incoming IP over NET/ROM frame.
890 */
891 if (frametype == NR_PROTOEXT &&
892 circuit_index == NR_PROTO_IP && circuit_id == NR_PROTO_IP) {
893 skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
894 skb_reset_transport_header(skb);
895
896 return nr_rx_ip(skb, dev);
897 }
898
899 /*
900 * Find an existing socket connection, based on circuit ID, if it's
901 * a Connect Request base it on their circuit ID.
902 *
903 * Circuit ID 0/0 is not valid but it could still be a "reset" for a
904 * circuit that no longer exists at the other end ...
905 */
906
907 sk = NULL;
908
909 if (circuit_index == 0 && circuit_id == 0) {
910 if (frametype == NR_CONNACK && flags == NR_CHOKE_FLAG)
911 sk = nr_find_peer(peer_circuit_index, peer_circuit_id, src);
912 } else {
913 if (frametype == NR_CONNREQ)
914 sk = nr_find_peer(circuit_index, circuit_id, src);
915 else
916 sk = nr_find_socket(circuit_index, circuit_id);
917 }
918
919 if (sk != NULL) {
920 bh_lock_sock(sk);
921 skb_reset_transport_header(skb);
922
923 if (frametype == NR_CONNACK && skb->len == 22)
924 nr_sk(sk)->bpqext = 1;
925 else
926 nr_sk(sk)->bpqext = 0;
927
928 ret = nr_process_rx_frame(sk, skb);
929 bh_unlock_sock(sk);
930 sock_put(sk);
931 return ret;
932 }
933
934 /*
935 * Now it should be a CONNREQ.
936 */
937 if (frametype != NR_CONNREQ) {
938 /*
939 * Here it would be nice to be able to send a reset but
940 * NET/ROM doesn't have one. We've tried to extend the protocol
941 * by sending NR_CONNACK | NR_CHOKE_FLAGS replies but that
942 * apparently kills BPQ boxes... :-(
943 * So now we try to follow the established behaviour of
944 * G8PZT's Xrouter which is sending packets with command type 7
945 * as an extension of the protocol.
946 */
947 if (sysctl_netrom_reset_circuit &&
948 (frametype != NR_RESET || flags != 0))
949 nr_transmit_reset(skb, 1);
950
951 return 0;
952 }
953
954 sk = nr_find_listener(dest);
955
956 user = (ax25_address *)(skb->data + 21);
957
958 if (sk == NULL || sk_acceptq_is_full(sk) ||
959 (make = nr_make_new(sk)) == NULL) {
960 nr_transmit_refusal(skb, 0);
961 if (sk)
962 sock_put(sk);
963 return 0;
964 }
965
966 bh_lock_sock(sk);
967
968 window = skb->data[20];
969
970 sock_hold(make);
971 skb->sk = make;
972 skb->destructor = sock_efree;
973 make->sk_state = TCP_ESTABLISHED;
974
975 /* Fill in his circuit details */
976 nr_make = nr_sk(make);
977 nr_make->source_addr = *dest;
978 nr_make->dest_addr = *src;
979 nr_make->user_addr = *user;
980
981 nr_make->your_index = circuit_index;
982 nr_make->your_id = circuit_id;
983
984 bh_unlock_sock(sk);
985 circuit = nr_find_next_circuit();
986 bh_lock_sock(sk);
987
988 nr_make->my_index = circuit / 256;
989 nr_make->my_id = circuit % 256;
990
991 circuit++;
992
993 /* Window negotiation */
994 if (window < nr_make->window)
995 nr_make->window = window;
996
997 /* L4 timeout negotiation */
998 if (skb->len == 37) {
999 timeout = skb->data[36] * 256 + skb->data[35];
1000 if (timeout * HZ < nr_make->t1)
1001 nr_make->t1 = timeout * HZ;
1002 nr_make->bpqext = 1;
1003 } else {
1004 nr_make->bpqext = 0;
1005 }
1006
1007 nr_write_internal(make, NR_CONNACK);
1008
1009 nr_make->condition = 0x00;
1010 nr_make->vs = 0;
1011 nr_make->va = 0;
1012 nr_make->vr = 0;
1013 nr_make->vl = 0;
1014 nr_make->state = NR_STATE_3;
1015 sk_acceptq_added(sk);
1016 skb_queue_head(&sk->sk_receive_queue, skb);
1017
1018 if (!sock_flag(sk, SOCK_DEAD))
1019 sk->sk_data_ready(sk);
1020
1021 bh_unlock_sock(sk);
1022 sock_put(sk);
1023
1024 nr_insert_socket(make);
1025
1026 nr_start_heartbeat(make);
1027 nr_start_idletimer(make);
1028
1029 return 1;
1030}
1031
1032static int nr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1033{
1034 struct sock *sk = sock->sk;
1035 struct nr_sock *nr = nr_sk(sk);
1036 DECLARE_SOCKADDR(struct sockaddr_ax25 *, usax, msg->msg_name);
1037 int err;
1038 struct sockaddr_ax25 sax;
1039 struct sk_buff *skb;
1040 unsigned char *asmptr;
1041 int size;
1042
1043 if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_CMSG_COMPAT))
1044 return -EINVAL;
1045
1046 lock_sock(sk);
1047 if (sock_flag(sk, SOCK_ZAPPED)) {
1048 err = -EADDRNOTAVAIL;
1049 goto out;
1050 }
1051
1052 if (sk->sk_shutdown & SEND_SHUTDOWN) {
1053 send_sig(SIGPIPE, current, 0);
1054 err = -EPIPE;
1055 goto out;
1056 }
1057
1058 if (nr->device == NULL) {
1059 err = -ENETUNREACH;
1060 goto out;
1061 }
1062
1063 if (usax) {
1064 if (msg->msg_namelen < sizeof(sax)) {
1065 err = -EINVAL;
1066 goto out;
1067 }
1068 sax = *usax;
1069 if (ax25cmp(&nr->dest_addr, &sax.sax25_call) != 0) {
1070 err = -EISCONN;
1071 goto out;
1072 }
1073 if (sax.sax25_family != AF_NETROM) {
1074 err = -EINVAL;
1075 goto out;
1076 }
1077 } else {
1078 if (sk->sk_state != TCP_ESTABLISHED) {
1079 err = -ENOTCONN;
1080 goto out;
1081 }
1082 sax.sax25_family = AF_NETROM;
1083 sax.sax25_call = nr->dest_addr;
1084 }
1085
1086 /* Build a packet - the conventional user limit is 236 bytes. We can
1087 do ludicrously large NetROM frames but must not overflow */
1088 if (len > 65536) {
1089 err = -EMSGSIZE;
1090 goto out;
1091 }
1092
1093 size = len + NR_NETWORK_LEN + NR_TRANSPORT_LEN;
1094
1095 if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
1096 goto out;
1097
1098 skb_reserve(skb, size - len);
1099 skb_reset_transport_header(skb);
1100
1101 /*
1102 * Push down the NET/ROM header
1103 */
1104
1105 asmptr = skb_push(skb, NR_TRANSPORT_LEN);
1106
1107 /* Build a NET/ROM Transport header */
1108
1109 *asmptr++ = nr->your_index;
1110 *asmptr++ = nr->your_id;
1111 *asmptr++ = 0; /* To be filled in later */
1112 *asmptr++ = 0; /* Ditto */
1113 *asmptr++ = NR_INFO;
1114
1115 /*
1116 * Put the data on the end
1117 */
1118 skb_put(skb, len);
1119
1120 /* User data follows immediately after the NET/ROM transport header */
1121 if (memcpy_from_msg(skb_transport_header(skb), msg, len)) {
1122 kfree_skb(skb);
1123 err = -EFAULT;
1124 goto out;
1125 }
1126
1127 if (sk->sk_state != TCP_ESTABLISHED) {
1128 kfree_skb(skb);
1129 err = -ENOTCONN;
1130 goto out;
1131 }
1132
1133 nr_output(sk, skb); /* Shove it onto the queue */
1134
1135 err = len;
1136out:
1137 release_sock(sk);
1138 return err;
1139}
1140
1141static int nr_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1142 int flags)
1143{
1144 struct sock *sk = sock->sk;
1145 DECLARE_SOCKADDR(struct sockaddr_ax25 *, sax, msg->msg_name);
1146 size_t copied;
1147 struct sk_buff *skb;
1148 int er;
1149
1150 /*
1151 * This works for seqpacket too. The receiver has ordered the queue for
1152 * us! We do one quick check first though
1153 */
1154
1155 lock_sock(sk);
1156 if (sk->sk_state != TCP_ESTABLISHED) {
1157 release_sock(sk);
1158 return -ENOTCONN;
1159 }
1160
1161 /* Now we can treat all alike */
1162 if ((skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &er)) == NULL) {
1163 release_sock(sk);
1164 return er;
1165 }
1166
1167 skb_reset_transport_header(skb);
1168 copied = skb->len;
1169
1170 if (copied > size) {
1171 copied = size;
1172 msg->msg_flags |= MSG_TRUNC;
1173 }
1174
1175 er = skb_copy_datagram_msg(skb, 0, msg, copied);
1176 if (er < 0) {
1177 skb_free_datagram(sk, skb);
1178 release_sock(sk);
1179 return er;
1180 }
1181
1182 if (sax != NULL) {
1183 memset(sax, 0, sizeof(*sax));
1184 sax->sax25_family = AF_NETROM;
1185 skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
1186 AX25_ADDR_LEN);
1187 msg->msg_namelen = sizeof(*sax);
1188 }
1189
1190 skb_free_datagram(sk, skb);
1191
1192 release_sock(sk);
1193 return copied;
1194}
1195
1196
1197static int nr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1198{
1199 struct sock *sk = sock->sk;
1200 void __user *argp = (void __user *)arg;
1201
1202 switch (cmd) {
1203 case TIOCOUTQ: {
1204 long amount;
1205
1206 lock_sock(sk);
1207 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1208 if (amount < 0)
1209 amount = 0;
1210 release_sock(sk);
1211 return put_user(amount, (int __user *)argp);
1212 }
1213
1214 case TIOCINQ: {
1215 struct sk_buff *skb;
1216 long amount = 0L;
1217
1218 lock_sock(sk);
1219 /* These two are safe on a single CPU system as only user tasks fiddle here */
1220 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1221 amount = skb->len;
1222 release_sock(sk);
1223 return put_user(amount, (int __user *)argp);
1224 }
1225
1226 case SIOCGIFADDR:
1227 case SIOCSIFADDR:
1228 case SIOCGIFDSTADDR:
1229 case SIOCSIFDSTADDR:
1230 case SIOCGIFBRDADDR:
1231 case SIOCSIFBRDADDR:
1232 case SIOCGIFNETMASK:
1233 case SIOCSIFNETMASK:
1234 case SIOCGIFMETRIC:
1235 case SIOCSIFMETRIC:
1236 return -EINVAL;
1237
1238 case SIOCADDRT:
1239 case SIOCDELRT:
1240 case SIOCNRDECOBS:
1241 if (!capable(CAP_NET_ADMIN))
1242 return -EPERM;
1243 return nr_rt_ioctl(cmd, argp);
1244
1245 default:
1246 return -ENOIOCTLCMD;
1247 }
1248
1249 return 0;
1250}
1251
1252#ifdef CONFIG_PROC_FS
1253
1254static void *nr_info_start(struct seq_file *seq, loff_t *pos)
1255 __acquires(&nr_list_lock)
1256{
1257 spin_lock_bh(&nr_list_lock);
1258 return seq_hlist_start_head(&nr_list, *pos);
1259}
1260
1261static void *nr_info_next(struct seq_file *seq, void *v, loff_t *pos)
1262{
1263 return seq_hlist_next(v, &nr_list, pos);
1264}
1265
1266static void nr_info_stop(struct seq_file *seq, void *v)
1267 __releases(&nr_list_lock)
1268{
1269 spin_unlock_bh(&nr_list_lock);
1270}
1271
1272static int nr_info_show(struct seq_file *seq, void *v)
1273{
1274 struct sock *s = sk_entry(v);
1275 struct net_device *dev;
1276 struct nr_sock *nr;
1277 const char *devname;
1278 char buf[11];
1279
1280 if (v == SEQ_START_TOKEN)
1281 seq_puts(seq,
1282"user_addr dest_node src_node dev my your st vs vr va t1 t2 t4 idle n2 wnd Snd-Q Rcv-Q inode\n");
1283
1284 else {
1285
1286 bh_lock_sock(s);
1287 nr = nr_sk(s);
1288
1289 if ((dev = nr->device) == NULL)
1290 devname = "???";
1291 else
1292 devname = dev->name;
1293
1294 seq_printf(seq, "%-9s ", ax2asc(buf, &nr->user_addr));
1295 seq_printf(seq, "%-9s ", ax2asc(buf, &nr->dest_addr));
1296 seq_printf(seq,
1297"%-9s %-3s %02X/%02X %02X/%02X %2d %3d %3d %3d %3lu/%03lu %2lu/%02lu %3lu/%03lu %3lu/%03lu %2d/%02d %3d %5d %5d %ld\n",
1298 ax2asc(buf, &nr->source_addr),
1299 devname,
1300 nr->my_index,
1301 nr->my_id,
1302 nr->your_index,
1303 nr->your_id,
1304 nr->state,
1305 nr->vs,
1306 nr->vr,
1307 nr->va,
1308 ax25_display_timer(&nr->t1timer) / HZ,
1309 nr->t1 / HZ,
1310 ax25_display_timer(&nr->t2timer) / HZ,
1311 nr->t2 / HZ,
1312 ax25_display_timer(&nr->t4timer) / HZ,
1313 nr->t4 / HZ,
1314 ax25_display_timer(&nr->idletimer) / (60 * HZ),
1315 nr->idle / (60 * HZ),
1316 nr->n2count,
1317 nr->n2,
1318 nr->window,
1319 sk_wmem_alloc_get(s),
1320 sk_rmem_alloc_get(s),
1321 s->sk_socket ? SOCK_INODE(s->sk_socket)->i_ino : 0L);
1322
1323 bh_unlock_sock(s);
1324 }
1325 return 0;
1326}
1327
1328static const struct seq_operations nr_info_seqops = {
1329 .start = nr_info_start,
1330 .next = nr_info_next,
1331 .stop = nr_info_stop,
1332 .show = nr_info_show,
1333};
1334#endif /* CONFIG_PROC_FS */
1335
1336static const struct net_proto_family nr_family_ops = {
1337 .family = PF_NETROM,
1338 .create = nr_create,
1339 .owner = THIS_MODULE,
1340};
1341
1342static const struct proto_ops nr_proto_ops = {
1343 .family = PF_NETROM,
1344 .owner = THIS_MODULE,
1345 .release = nr_release,
1346 .bind = nr_bind,
1347 .connect = nr_connect,
1348 .socketpair = sock_no_socketpair,
1349 .accept = nr_accept,
1350 .getname = nr_getname,
1351 .poll = datagram_poll,
1352 .ioctl = nr_ioctl,
1353 .gettstamp = sock_gettstamp,
1354 .listen = nr_listen,
1355 .shutdown = sock_no_shutdown,
1356 .setsockopt = nr_setsockopt,
1357 .getsockopt = nr_getsockopt,
1358 .sendmsg = nr_sendmsg,
1359 .recvmsg = nr_recvmsg,
1360 .mmap = sock_no_mmap,
1361 .sendpage = sock_no_sendpage,
1362};
1363
1364static struct notifier_block nr_dev_notifier = {
1365 .notifier_call = nr_device_event,
1366};
1367
1368static struct net_device **dev_nr;
1369
1370static struct ax25_protocol nr_pid = {
1371 .pid = AX25_P_NETROM,
1372 .func = nr_route_frame
1373};
1374
1375static struct ax25_linkfail nr_linkfail_notifier = {
1376 .func = nr_link_failed,
1377};
1378
1379static int __init nr_proto_init(void)
1380{
1381 int i;
1382 int rc = proto_register(&nr_proto, 0);
1383
1384 if (rc)
1385 return rc;
1386
1387 if (nr_ndevs > 0x7fffffff/sizeof(struct net_device *)) {
1388 pr_err("NET/ROM: %s - nr_ndevs parameter too large\n",
1389 __func__);
1390 rc = -EINVAL;
1391 goto unregister_proto;
1392 }
1393
1394 dev_nr = kcalloc(nr_ndevs, sizeof(struct net_device *), GFP_KERNEL);
1395 if (!dev_nr) {
1396 pr_err("NET/ROM: %s - unable to allocate device array\n",
1397 __func__);
1398 rc = -ENOMEM;
1399 goto unregister_proto;
1400 }
1401
1402 for (i = 0; i < nr_ndevs; i++) {
1403 char name[IFNAMSIZ];
1404 struct net_device *dev;
1405
1406 sprintf(name, "nr%d", i);
1407 dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, nr_setup);
1408 if (!dev) {
1409 rc = -ENOMEM;
1410 goto fail;
1411 }
1412
1413 dev->base_addr = i;
1414 rc = register_netdev(dev);
1415 if (rc) {
1416 free_netdev(dev);
1417 goto fail;
1418 }
1419 nr_set_lockdep_key(dev);
1420 dev_nr[i] = dev;
1421 }
1422
1423 rc = sock_register(&nr_family_ops);
1424 if (rc)
1425 goto fail;
1426
1427 rc = register_netdevice_notifier(&nr_dev_notifier);
1428 if (rc)
1429 goto out_sock;
1430
1431 ax25_register_pid(&nr_pid);
1432 ax25_linkfail_register(&nr_linkfail_notifier);
1433
1434#ifdef CONFIG_SYSCTL
1435 rc = nr_register_sysctl();
1436 if (rc)
1437 goto out_sysctl;
1438#endif
1439
1440 nr_loopback_init();
1441
1442 rc = -ENOMEM;
1443 if (!proc_create_seq("nr", 0444, init_net.proc_net, &nr_info_seqops))
1444 goto proc_remove1;
1445 if (!proc_create_seq("nr_neigh", 0444, init_net.proc_net,
1446 &nr_neigh_seqops))
1447 goto proc_remove2;
1448 if (!proc_create_seq("nr_nodes", 0444, init_net.proc_net,
1449 &nr_node_seqops))
1450 goto proc_remove3;
1451
1452 return 0;
1453
1454proc_remove3:
1455 remove_proc_entry("nr_neigh", init_net.proc_net);
1456proc_remove2:
1457 remove_proc_entry("nr", init_net.proc_net);
1458proc_remove1:
1459
1460 nr_loopback_clear();
1461 nr_rt_free();
1462
1463#ifdef CONFIG_SYSCTL
1464 nr_unregister_sysctl();
1465out_sysctl:
1466#endif
1467 ax25_linkfail_release(&nr_linkfail_notifier);
1468 ax25_protocol_release(AX25_P_NETROM);
1469 unregister_netdevice_notifier(&nr_dev_notifier);
1470out_sock:
1471 sock_unregister(PF_NETROM);
1472fail:
1473 while (--i >= 0) {
1474 unregister_netdev(dev_nr[i]);
1475 free_netdev(dev_nr[i]);
1476 }
1477 kfree(dev_nr);
1478unregister_proto:
1479 proto_unregister(&nr_proto);
1480 return rc;
1481}
1482
1483module_init(nr_proto_init);
1484
1485module_param(nr_ndevs, int, 0);
1486MODULE_PARM_DESC(nr_ndevs, "number of NET/ROM devices");
1487
1488MODULE_AUTHOR("Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>");
1489MODULE_DESCRIPTION("The amateur radio NET/ROM network and transport layer protocol");
1490MODULE_LICENSE("GPL");
1491MODULE_ALIAS_NETPROTO(PF_NETROM);
1492
1493static void __exit nr_exit(void)
1494{
1495 int i;
1496
1497 remove_proc_entry("nr", init_net.proc_net);
1498 remove_proc_entry("nr_neigh", init_net.proc_net);
1499 remove_proc_entry("nr_nodes", init_net.proc_net);
1500 nr_loopback_clear();
1501
1502 nr_rt_free();
1503
1504#ifdef CONFIG_SYSCTL
1505 nr_unregister_sysctl();
1506#endif
1507
1508 ax25_linkfail_release(&nr_linkfail_notifier);
1509 ax25_protocol_release(AX25_P_NETROM);
1510
1511 unregister_netdevice_notifier(&nr_dev_notifier);
1512
1513 sock_unregister(PF_NETROM);
1514
1515 for (i = 0; i < nr_ndevs; i++) {
1516 struct net_device *dev = dev_nr[i];
1517 if (dev) {
1518 unregister_netdev(dev);
1519 free_netdev(dev);
1520 }
1521 }
1522
1523 kfree(dev_nr);
1524 proto_unregister(&nr_proto);
1525}
1526module_exit(nr_exit);