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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 int 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(opt)))
310 return -EFAULT;
311
312 switch (optname) {
313 case NETROM_T1:
314 if (opt < 1 || opt > UINT_MAX / HZ)
315 return -EINVAL;
316 nr->t1 = opt * HZ;
317 return 0;
318
319 case NETROM_T2:
320 if (opt < 1 || opt > UINT_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 > UINT_MAX / HZ)
333 return -EINVAL;
334 nr->t4 = opt * HZ;
335 return 0;
336
337 case NETROM_IDLE:
338 if (opt > UINT_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 (sock->state != SS_UNCONNECTED) {
404 release_sock(sk);
405 return -EINVAL;
406 }
407
408 if (sk->sk_state != TCP_LISTEN) {
409 memset(&nr_sk(sk)->user_addr, 0, AX25_ADDR_LEN);
410 sk->sk_max_ack_backlog = backlog;
411 sk->sk_state = TCP_LISTEN;
412 release_sock(sk);
413 return 0;
414 }
415 release_sock(sk);
416
417 return -EOPNOTSUPP;
418}
419
420static struct proto nr_proto = {
421 .name = "NETROM",
422 .owner = THIS_MODULE,
423 .obj_size = sizeof(struct nr_sock),
424};
425
426static int nr_create(struct net *net, struct socket *sock, int protocol,
427 int kern)
428{
429 struct sock *sk;
430 struct nr_sock *nr;
431
432 if (!net_eq(net, &init_net))
433 return -EAFNOSUPPORT;
434
435 if (sock->type != SOCK_SEQPACKET || protocol != 0)
436 return -ESOCKTNOSUPPORT;
437
438 sk = sk_alloc(net, PF_NETROM, GFP_ATOMIC, &nr_proto, kern);
439 if (sk == NULL)
440 return -ENOMEM;
441
442 nr = nr_sk(sk);
443
444 sock_init_data(sock, sk);
445
446 sock->ops = &nr_proto_ops;
447 sk->sk_protocol = protocol;
448
449 skb_queue_head_init(&nr->ack_queue);
450 skb_queue_head_init(&nr->reseq_queue);
451 skb_queue_head_init(&nr->frag_queue);
452
453 nr_init_timers(sk);
454
455 nr->t1 =
456 msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_timeout));
457 nr->t2 =
458 msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_acknowledge_delay));
459 nr->n2 =
460 msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_maximum_tries));
461 nr->t4 =
462 msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_busy_delay));
463 nr->idle =
464 msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_no_activity_timeout));
465 nr->window = READ_ONCE(sysctl_netrom_transport_requested_window_size);
466
467 nr->bpqext = 1;
468 nr->state = NR_STATE_0;
469
470 return 0;
471}
472
473static struct sock *nr_make_new(struct sock *osk)
474{
475 struct sock *sk;
476 struct nr_sock *nr, *onr;
477
478 if (osk->sk_type != SOCK_SEQPACKET)
479 return NULL;
480
481 sk = sk_alloc(sock_net(osk), PF_NETROM, GFP_ATOMIC, osk->sk_prot, 0);
482 if (sk == NULL)
483 return NULL;
484
485 nr = nr_sk(sk);
486
487 sock_init_data(NULL, sk);
488
489 sk->sk_type = osk->sk_type;
490 sk->sk_priority = READ_ONCE(osk->sk_priority);
491 sk->sk_protocol = osk->sk_protocol;
492 sk->sk_rcvbuf = osk->sk_rcvbuf;
493 sk->sk_sndbuf = osk->sk_sndbuf;
494 sk->sk_state = TCP_ESTABLISHED;
495 sock_copy_flags(sk, osk);
496
497 skb_queue_head_init(&nr->ack_queue);
498 skb_queue_head_init(&nr->reseq_queue);
499 skb_queue_head_init(&nr->frag_queue);
500
501 nr_init_timers(sk);
502
503 onr = nr_sk(osk);
504
505 nr->t1 = onr->t1;
506 nr->t2 = onr->t2;
507 nr->n2 = onr->n2;
508 nr->t4 = onr->t4;
509 nr->idle = onr->idle;
510 nr->window = onr->window;
511
512 nr->device = onr->device;
513 nr->bpqext = onr->bpqext;
514
515 return sk;
516}
517
518static int nr_release(struct socket *sock)
519{
520 struct sock *sk = sock->sk;
521 struct nr_sock *nr;
522
523 if (sk == NULL) return 0;
524
525 sock_hold(sk);
526 sock_orphan(sk);
527 lock_sock(sk);
528 nr = nr_sk(sk);
529
530 switch (nr->state) {
531 case NR_STATE_0:
532 case NR_STATE_1:
533 case NR_STATE_2:
534 nr_disconnect(sk, 0);
535 nr_destroy_socket(sk);
536 break;
537
538 case NR_STATE_3:
539 nr_clear_queues(sk);
540 nr->n2count = 0;
541 nr_write_internal(sk, NR_DISCREQ);
542 nr_start_t1timer(sk);
543 nr_stop_t2timer(sk);
544 nr_stop_t4timer(sk);
545 nr_stop_idletimer(sk);
546 nr->state = NR_STATE_2;
547 sk->sk_state = TCP_CLOSE;
548 sk->sk_shutdown |= SEND_SHUTDOWN;
549 sk->sk_state_change(sk);
550 sock_set_flag(sk, SOCK_DESTROY);
551 break;
552
553 default:
554 break;
555 }
556
557 sock->sk = NULL;
558 release_sock(sk);
559 sock_put(sk);
560
561 return 0;
562}
563
564static int nr_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
565{
566 struct sock *sk = sock->sk;
567 struct nr_sock *nr = nr_sk(sk);
568 struct full_sockaddr_ax25 *addr = (struct full_sockaddr_ax25 *)uaddr;
569 struct net_device *dev;
570 ax25_uid_assoc *user;
571 ax25_address *source;
572
573 lock_sock(sk);
574 if (!sock_flag(sk, SOCK_ZAPPED)) {
575 release_sock(sk);
576 return -EINVAL;
577 }
578 if (addr_len < sizeof(struct sockaddr_ax25) || addr_len > sizeof(struct full_sockaddr_ax25)) {
579 release_sock(sk);
580 return -EINVAL;
581 }
582 if (addr_len < (addr->fsa_ax25.sax25_ndigis * sizeof(ax25_address) + sizeof(struct sockaddr_ax25))) {
583 release_sock(sk);
584 return -EINVAL;
585 }
586 if (addr->fsa_ax25.sax25_family != AF_NETROM) {
587 release_sock(sk);
588 return -EINVAL;
589 }
590 if ((dev = nr_dev_get(&addr->fsa_ax25.sax25_call)) == NULL) {
591 release_sock(sk);
592 return -EADDRNOTAVAIL;
593 }
594
595 /*
596 * Only the super user can set an arbitrary user callsign.
597 */
598 if (addr->fsa_ax25.sax25_ndigis == 1) {
599 if (!capable(CAP_NET_BIND_SERVICE)) {
600 dev_put(dev);
601 release_sock(sk);
602 return -EPERM;
603 }
604 nr->user_addr = addr->fsa_digipeater[0];
605 nr->source_addr = addr->fsa_ax25.sax25_call;
606 } else {
607 source = &addr->fsa_ax25.sax25_call;
608
609 user = ax25_findbyuid(current_euid());
610 if (user) {
611 nr->user_addr = user->call;
612 ax25_uid_put(user);
613 } else {
614 if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE)) {
615 release_sock(sk);
616 dev_put(dev);
617 return -EPERM;
618 }
619 nr->user_addr = *source;
620 }
621
622 nr->source_addr = *source;
623 }
624
625 nr->device = dev;
626 nr_insert_socket(sk);
627
628 sock_reset_flag(sk, SOCK_ZAPPED);
629 dev_put(dev);
630 release_sock(sk);
631
632 return 0;
633}
634
635static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
636 int addr_len, int flags)
637{
638 struct sock *sk = sock->sk;
639 struct nr_sock *nr = nr_sk(sk);
640 struct sockaddr_ax25 *addr = (struct sockaddr_ax25 *)uaddr;
641 const ax25_address *source = NULL;
642 ax25_uid_assoc *user;
643 struct net_device *dev;
644 int err = 0;
645
646 lock_sock(sk);
647 if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
648 sock->state = SS_CONNECTED;
649 goto out_release; /* Connect completed during a ERESTARTSYS event */
650 }
651
652 if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
653 sock->state = SS_UNCONNECTED;
654 err = -ECONNREFUSED;
655 goto out_release;
656 }
657
658 if (sk->sk_state == TCP_ESTABLISHED) {
659 err = -EISCONN; /* No reconnect on a seqpacket socket */
660 goto out_release;
661 }
662
663 if (sock->state == SS_CONNECTING) {
664 err = -EALREADY;
665 goto out_release;
666 }
667
668 sk->sk_state = TCP_CLOSE;
669 sock->state = SS_UNCONNECTED;
670
671 if (addr_len != sizeof(struct sockaddr_ax25) && addr_len != sizeof(struct full_sockaddr_ax25)) {
672 err = -EINVAL;
673 goto out_release;
674 }
675 if (addr->sax25_family != AF_NETROM) {
676 err = -EINVAL;
677 goto out_release;
678 }
679 if (sock_flag(sk, SOCK_ZAPPED)) { /* Must bind first - autobinding in this may or may not work */
680 sock_reset_flag(sk, SOCK_ZAPPED);
681
682 if ((dev = nr_dev_first()) == NULL) {
683 err = -ENETUNREACH;
684 goto out_release;
685 }
686 source = (const ax25_address *)dev->dev_addr;
687
688 user = ax25_findbyuid(current_euid());
689 if (user) {
690 nr->user_addr = user->call;
691 ax25_uid_put(user);
692 } else {
693 if (ax25_uid_policy && !capable(CAP_NET_ADMIN)) {
694 dev_put(dev);
695 err = -EPERM;
696 goto out_release;
697 }
698 nr->user_addr = *source;
699 }
700
701 nr->source_addr = *source;
702 nr->device = dev;
703
704 dev_put(dev);
705 nr_insert_socket(sk); /* Finish the bind */
706 }
707
708 nr->dest_addr = addr->sax25_call;
709
710 release_sock(sk);
711 circuit = nr_find_next_circuit();
712 lock_sock(sk);
713
714 nr->my_index = circuit / 256;
715 nr->my_id = circuit % 256;
716
717 circuit++;
718
719 /* Move to connecting socket, start sending Connect Requests */
720 sock->state = SS_CONNECTING;
721 sk->sk_state = TCP_SYN_SENT;
722
723 nr_establish_data_link(sk);
724
725 nr->state = NR_STATE_1;
726
727 nr_start_heartbeat(sk);
728
729 /* Now the loop */
730 if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
731 err = -EINPROGRESS;
732 goto out_release;
733 }
734
735 /*
736 * A Connect Ack with Choke or timeout or failed routing will go to
737 * closed.
738 */
739 if (sk->sk_state == TCP_SYN_SENT) {
740 DEFINE_WAIT(wait);
741
742 for (;;) {
743 prepare_to_wait(sk_sleep(sk), &wait,
744 TASK_INTERRUPTIBLE);
745 if (sk->sk_state != TCP_SYN_SENT)
746 break;
747 if (!signal_pending(current)) {
748 release_sock(sk);
749 schedule();
750 lock_sock(sk);
751 continue;
752 }
753 err = -ERESTARTSYS;
754 break;
755 }
756 finish_wait(sk_sleep(sk), &wait);
757 if (err)
758 goto out_release;
759 }
760
761 if (sk->sk_state != TCP_ESTABLISHED) {
762 sock->state = SS_UNCONNECTED;
763 err = sock_error(sk); /* Always set at this point */
764 goto out_release;
765 }
766
767 sock->state = SS_CONNECTED;
768
769out_release:
770 release_sock(sk);
771
772 return err;
773}
774
775static int nr_accept(struct socket *sock, struct socket *newsock,
776 struct proto_accept_arg *arg)
777{
778 struct sk_buff *skb;
779 struct sock *newsk;
780 DEFINE_WAIT(wait);
781 struct sock *sk;
782 int err = 0;
783
784 if ((sk = sock->sk) == NULL)
785 return -EINVAL;
786
787 lock_sock(sk);
788 if (sk->sk_type != SOCK_SEQPACKET) {
789 err = -EOPNOTSUPP;
790 goto out_release;
791 }
792
793 if (sk->sk_state != TCP_LISTEN) {
794 err = -EINVAL;
795 goto out_release;
796 }
797
798 /*
799 * The write queue this time is holding sockets ready to use
800 * hooked into the SABM we saved
801 */
802 for (;;) {
803 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
804 skb = skb_dequeue(&sk->sk_receive_queue);
805 if (skb)
806 break;
807
808 if (arg->flags & O_NONBLOCK) {
809 err = -EWOULDBLOCK;
810 break;
811 }
812 if (!signal_pending(current)) {
813 release_sock(sk);
814 schedule();
815 lock_sock(sk);
816 continue;
817 }
818 err = -ERESTARTSYS;
819 break;
820 }
821 finish_wait(sk_sleep(sk), &wait);
822 if (err)
823 goto out_release;
824
825 newsk = skb->sk;
826 sock_graft(newsk, newsock);
827
828 /* Now attach up the new socket */
829 kfree_skb(skb);
830 sk_acceptq_removed(sk);
831
832out_release:
833 release_sock(sk);
834
835 return err;
836}
837
838static int nr_getname(struct socket *sock, struct sockaddr *uaddr,
839 int peer)
840{
841 struct full_sockaddr_ax25 *sax = (struct full_sockaddr_ax25 *)uaddr;
842 struct sock *sk = sock->sk;
843 struct nr_sock *nr = nr_sk(sk);
844 int uaddr_len;
845
846 memset(&sax->fsa_ax25, 0, sizeof(struct sockaddr_ax25));
847
848 lock_sock(sk);
849 if (peer != 0) {
850 if (sk->sk_state != TCP_ESTABLISHED) {
851 release_sock(sk);
852 return -ENOTCONN;
853 }
854 sax->fsa_ax25.sax25_family = AF_NETROM;
855 sax->fsa_ax25.sax25_ndigis = 1;
856 sax->fsa_ax25.sax25_call = nr->user_addr;
857 memset(sax->fsa_digipeater, 0, sizeof(sax->fsa_digipeater));
858 sax->fsa_digipeater[0] = nr->dest_addr;
859 uaddr_len = sizeof(struct full_sockaddr_ax25);
860 } else {
861 sax->fsa_ax25.sax25_family = AF_NETROM;
862 sax->fsa_ax25.sax25_ndigis = 0;
863 sax->fsa_ax25.sax25_call = nr->source_addr;
864 uaddr_len = sizeof(struct sockaddr_ax25);
865 }
866 release_sock(sk);
867
868 return uaddr_len;
869}
870
871int nr_rx_frame(struct sk_buff *skb, struct net_device *dev)
872{
873 struct sock *sk;
874 struct sock *make;
875 struct nr_sock *nr_make;
876 ax25_address *src, *dest, *user;
877 unsigned short circuit_index, circuit_id;
878 unsigned short peer_circuit_index, peer_circuit_id;
879 unsigned short frametype, flags, window, timeout;
880 int ret;
881
882 skb_orphan(skb);
883
884 /*
885 * skb->data points to the netrom frame start
886 */
887
888 src = (ax25_address *)(skb->data + 0);
889 dest = (ax25_address *)(skb->data + 7);
890
891 circuit_index = skb->data[15];
892 circuit_id = skb->data[16];
893 peer_circuit_index = skb->data[17];
894 peer_circuit_id = skb->data[18];
895 frametype = skb->data[19] & 0x0F;
896 flags = skb->data[19] & 0xF0;
897
898 /*
899 * Check for an incoming IP over NET/ROM frame.
900 */
901 if (frametype == NR_PROTOEXT &&
902 circuit_index == NR_PROTO_IP && circuit_id == NR_PROTO_IP) {
903 skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
904 skb_reset_transport_header(skb);
905
906 return nr_rx_ip(skb, dev);
907 }
908
909 /*
910 * Find an existing socket connection, based on circuit ID, if it's
911 * a Connect Request base it on their circuit ID.
912 *
913 * Circuit ID 0/0 is not valid but it could still be a "reset" for a
914 * circuit that no longer exists at the other end ...
915 */
916
917 sk = NULL;
918
919 if (circuit_index == 0 && circuit_id == 0) {
920 if (frametype == NR_CONNACK && flags == NR_CHOKE_FLAG)
921 sk = nr_find_peer(peer_circuit_index, peer_circuit_id, src);
922 } else {
923 if (frametype == NR_CONNREQ)
924 sk = nr_find_peer(circuit_index, circuit_id, src);
925 else
926 sk = nr_find_socket(circuit_index, circuit_id);
927 }
928
929 if (sk != NULL) {
930 bh_lock_sock(sk);
931 skb_reset_transport_header(skb);
932
933 if (frametype == NR_CONNACK && skb->len == 22)
934 nr_sk(sk)->bpqext = 1;
935 else
936 nr_sk(sk)->bpqext = 0;
937
938 ret = nr_process_rx_frame(sk, skb);
939 bh_unlock_sock(sk);
940 sock_put(sk);
941 return ret;
942 }
943
944 /*
945 * Now it should be a CONNREQ.
946 */
947 if (frametype != NR_CONNREQ) {
948 /*
949 * Here it would be nice to be able to send a reset but
950 * NET/ROM doesn't have one. We've tried to extend the protocol
951 * by sending NR_CONNACK | NR_CHOKE_FLAGS replies but that
952 * apparently kills BPQ boxes... :-(
953 * So now we try to follow the established behaviour of
954 * G8PZT's Xrouter which is sending packets with command type 7
955 * as an extension of the protocol.
956 */
957 if (READ_ONCE(sysctl_netrom_reset_circuit) &&
958 (frametype != NR_RESET || flags != 0))
959 nr_transmit_reset(skb, 1);
960
961 return 0;
962 }
963
964 sk = nr_find_listener(dest);
965
966 user = (ax25_address *)(skb->data + 21);
967
968 if (sk == NULL || sk_acceptq_is_full(sk) ||
969 (make = nr_make_new(sk)) == NULL) {
970 nr_transmit_refusal(skb, 0);
971 if (sk)
972 sock_put(sk);
973 return 0;
974 }
975
976 bh_lock_sock(sk);
977
978 window = skb->data[20];
979
980 sock_hold(make);
981 skb->sk = make;
982 skb->destructor = sock_efree;
983 make->sk_state = TCP_ESTABLISHED;
984
985 /* Fill in his circuit details */
986 nr_make = nr_sk(make);
987 nr_make->source_addr = *dest;
988 nr_make->dest_addr = *src;
989 nr_make->user_addr = *user;
990
991 nr_make->your_index = circuit_index;
992 nr_make->your_id = circuit_id;
993
994 bh_unlock_sock(sk);
995 circuit = nr_find_next_circuit();
996 bh_lock_sock(sk);
997
998 nr_make->my_index = circuit / 256;
999 nr_make->my_id = circuit % 256;
1000
1001 circuit++;
1002
1003 /* Window negotiation */
1004 if (window < nr_make->window)
1005 nr_make->window = window;
1006
1007 /* L4 timeout negotiation */
1008 if (skb->len == 37) {
1009 timeout = skb->data[36] * 256 + skb->data[35];
1010 if (timeout * HZ < nr_make->t1)
1011 nr_make->t1 = timeout * HZ;
1012 nr_make->bpqext = 1;
1013 } else {
1014 nr_make->bpqext = 0;
1015 }
1016
1017 nr_write_internal(make, NR_CONNACK);
1018
1019 nr_make->condition = 0x00;
1020 nr_make->vs = 0;
1021 nr_make->va = 0;
1022 nr_make->vr = 0;
1023 nr_make->vl = 0;
1024 nr_make->state = NR_STATE_3;
1025 sk_acceptq_added(sk);
1026 skb_queue_head(&sk->sk_receive_queue, skb);
1027
1028 if (!sock_flag(sk, SOCK_DEAD))
1029 sk->sk_data_ready(sk);
1030
1031 bh_unlock_sock(sk);
1032 sock_put(sk);
1033
1034 nr_insert_socket(make);
1035
1036 nr_start_heartbeat(make);
1037 nr_start_idletimer(make);
1038
1039 return 1;
1040}
1041
1042static int nr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1043{
1044 struct sock *sk = sock->sk;
1045 struct nr_sock *nr = nr_sk(sk);
1046 DECLARE_SOCKADDR(struct sockaddr_ax25 *, usax, msg->msg_name);
1047 int err;
1048 struct sockaddr_ax25 sax;
1049 struct sk_buff *skb;
1050 unsigned char *asmptr;
1051 int size;
1052
1053 if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_CMSG_COMPAT))
1054 return -EINVAL;
1055
1056 lock_sock(sk);
1057 if (sock_flag(sk, SOCK_ZAPPED)) {
1058 err = -EADDRNOTAVAIL;
1059 goto out;
1060 }
1061
1062 if (sk->sk_shutdown & SEND_SHUTDOWN) {
1063 send_sig(SIGPIPE, current, 0);
1064 err = -EPIPE;
1065 goto out;
1066 }
1067
1068 if (nr->device == NULL) {
1069 err = -ENETUNREACH;
1070 goto out;
1071 }
1072
1073 if (usax) {
1074 if (msg->msg_namelen < sizeof(sax)) {
1075 err = -EINVAL;
1076 goto out;
1077 }
1078 sax = *usax;
1079 if (ax25cmp(&nr->dest_addr, &sax.sax25_call) != 0) {
1080 err = -EISCONN;
1081 goto out;
1082 }
1083 if (sax.sax25_family != AF_NETROM) {
1084 err = -EINVAL;
1085 goto out;
1086 }
1087 } else {
1088 if (sk->sk_state != TCP_ESTABLISHED) {
1089 err = -ENOTCONN;
1090 goto out;
1091 }
1092 sax.sax25_family = AF_NETROM;
1093 sax.sax25_call = nr->dest_addr;
1094 }
1095
1096 /* Build a packet - the conventional user limit is 236 bytes. We can
1097 do ludicrously large NetROM frames but must not overflow */
1098 if (len > 65536) {
1099 err = -EMSGSIZE;
1100 goto out;
1101 }
1102
1103 size = len + NR_NETWORK_LEN + NR_TRANSPORT_LEN;
1104
1105 if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
1106 goto out;
1107
1108 skb_reserve(skb, size - len);
1109 skb_reset_transport_header(skb);
1110
1111 /*
1112 * Push down the NET/ROM header
1113 */
1114
1115 asmptr = skb_push(skb, NR_TRANSPORT_LEN);
1116
1117 /* Build a NET/ROM Transport header */
1118
1119 *asmptr++ = nr->your_index;
1120 *asmptr++ = nr->your_id;
1121 *asmptr++ = 0; /* To be filled in later */
1122 *asmptr++ = 0; /* Ditto */
1123 *asmptr++ = NR_INFO;
1124
1125 /*
1126 * Put the data on the end
1127 */
1128 skb_put(skb, len);
1129
1130 /* User data follows immediately after the NET/ROM transport header */
1131 if (memcpy_from_msg(skb_transport_header(skb), msg, len)) {
1132 kfree_skb(skb);
1133 err = -EFAULT;
1134 goto out;
1135 }
1136
1137 if (sk->sk_state != TCP_ESTABLISHED) {
1138 kfree_skb(skb);
1139 err = -ENOTCONN;
1140 goto out;
1141 }
1142
1143 nr_output(sk, skb); /* Shove it onto the queue */
1144
1145 err = len;
1146out:
1147 release_sock(sk);
1148 return err;
1149}
1150
1151static int nr_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1152 int flags)
1153{
1154 struct sock *sk = sock->sk;
1155 DECLARE_SOCKADDR(struct sockaddr_ax25 *, sax, msg->msg_name);
1156 size_t copied;
1157 struct sk_buff *skb;
1158 int er;
1159
1160 /*
1161 * This works for seqpacket too. The receiver has ordered the queue for
1162 * us! We do one quick check first though
1163 */
1164
1165 lock_sock(sk);
1166 if (sk->sk_state != TCP_ESTABLISHED) {
1167 release_sock(sk);
1168 return -ENOTCONN;
1169 }
1170
1171 /* Now we can treat all alike */
1172 skb = skb_recv_datagram(sk, flags, &er);
1173 if (!skb) {
1174 release_sock(sk);
1175 return er;
1176 }
1177
1178 skb_reset_transport_header(skb);
1179 copied = skb->len;
1180
1181 if (copied > size) {
1182 copied = size;
1183 msg->msg_flags |= MSG_TRUNC;
1184 }
1185
1186 er = skb_copy_datagram_msg(skb, 0, msg, copied);
1187 if (er < 0) {
1188 skb_free_datagram(sk, skb);
1189 release_sock(sk);
1190 return er;
1191 }
1192
1193 if (sax != NULL) {
1194 memset(sax, 0, sizeof(*sax));
1195 sax->sax25_family = AF_NETROM;
1196 skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
1197 AX25_ADDR_LEN);
1198 msg->msg_namelen = sizeof(*sax);
1199 }
1200
1201 skb_free_datagram(sk, skb);
1202
1203 release_sock(sk);
1204 return copied;
1205}
1206
1207
1208static int nr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1209{
1210 struct sock *sk = sock->sk;
1211 void __user *argp = (void __user *)arg;
1212
1213 switch (cmd) {
1214 case TIOCOUTQ: {
1215 long amount;
1216
1217 lock_sock(sk);
1218 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1219 if (amount < 0)
1220 amount = 0;
1221 release_sock(sk);
1222 return put_user(amount, (int __user *)argp);
1223 }
1224
1225 case TIOCINQ: {
1226 struct sk_buff *skb;
1227 long amount = 0L;
1228
1229 lock_sock(sk);
1230 /* These two are safe on a single CPU system as only user tasks fiddle here */
1231 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1232 amount = skb->len;
1233 release_sock(sk);
1234 return put_user(amount, (int __user *)argp);
1235 }
1236
1237 case SIOCGIFADDR:
1238 case SIOCSIFADDR:
1239 case SIOCGIFDSTADDR:
1240 case SIOCSIFDSTADDR:
1241 case SIOCGIFBRDADDR:
1242 case SIOCSIFBRDADDR:
1243 case SIOCGIFNETMASK:
1244 case SIOCSIFNETMASK:
1245 case SIOCGIFMETRIC:
1246 case SIOCSIFMETRIC:
1247 return -EINVAL;
1248
1249 case SIOCADDRT:
1250 case SIOCDELRT:
1251 case SIOCNRDECOBS:
1252 if (!capable(CAP_NET_ADMIN))
1253 return -EPERM;
1254 return nr_rt_ioctl(cmd, argp);
1255
1256 default:
1257 return -ENOIOCTLCMD;
1258 }
1259
1260 return 0;
1261}
1262
1263#ifdef CONFIG_PROC_FS
1264
1265static void *nr_info_start(struct seq_file *seq, loff_t *pos)
1266 __acquires(&nr_list_lock)
1267{
1268 spin_lock_bh(&nr_list_lock);
1269 return seq_hlist_start_head(&nr_list, *pos);
1270}
1271
1272static void *nr_info_next(struct seq_file *seq, void *v, loff_t *pos)
1273{
1274 return seq_hlist_next(v, &nr_list, pos);
1275}
1276
1277static void nr_info_stop(struct seq_file *seq, void *v)
1278 __releases(&nr_list_lock)
1279{
1280 spin_unlock_bh(&nr_list_lock);
1281}
1282
1283static int nr_info_show(struct seq_file *seq, void *v)
1284{
1285 struct sock *s = sk_entry(v);
1286 struct net_device *dev;
1287 struct nr_sock *nr;
1288 const char *devname;
1289 char buf[11];
1290
1291 if (v == SEQ_START_TOKEN)
1292 seq_puts(seq,
1293"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");
1294
1295 else {
1296
1297 bh_lock_sock(s);
1298 nr = nr_sk(s);
1299
1300 if ((dev = nr->device) == NULL)
1301 devname = "???";
1302 else
1303 devname = dev->name;
1304
1305 seq_printf(seq, "%-9s ", ax2asc(buf, &nr->user_addr));
1306 seq_printf(seq, "%-9s ", ax2asc(buf, &nr->dest_addr));
1307 seq_printf(seq,
1308"%-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",
1309 ax2asc(buf, &nr->source_addr),
1310 devname,
1311 nr->my_index,
1312 nr->my_id,
1313 nr->your_index,
1314 nr->your_id,
1315 nr->state,
1316 nr->vs,
1317 nr->vr,
1318 nr->va,
1319 ax25_display_timer(&nr->t1timer) / HZ,
1320 nr->t1 / HZ,
1321 ax25_display_timer(&nr->t2timer) / HZ,
1322 nr->t2 / HZ,
1323 ax25_display_timer(&nr->t4timer) / HZ,
1324 nr->t4 / HZ,
1325 ax25_display_timer(&nr->idletimer) / (60 * HZ),
1326 nr->idle / (60 * HZ),
1327 nr->n2count,
1328 nr->n2,
1329 nr->window,
1330 sk_wmem_alloc_get(s),
1331 sk_rmem_alloc_get(s),
1332 s->sk_socket ? SOCK_INODE(s->sk_socket)->i_ino : 0L);
1333
1334 bh_unlock_sock(s);
1335 }
1336 return 0;
1337}
1338
1339static const struct seq_operations nr_info_seqops = {
1340 .start = nr_info_start,
1341 .next = nr_info_next,
1342 .stop = nr_info_stop,
1343 .show = nr_info_show,
1344};
1345#endif /* CONFIG_PROC_FS */
1346
1347static const struct net_proto_family nr_family_ops = {
1348 .family = PF_NETROM,
1349 .create = nr_create,
1350 .owner = THIS_MODULE,
1351};
1352
1353static const struct proto_ops nr_proto_ops = {
1354 .family = PF_NETROM,
1355 .owner = THIS_MODULE,
1356 .release = nr_release,
1357 .bind = nr_bind,
1358 .connect = nr_connect,
1359 .socketpair = sock_no_socketpair,
1360 .accept = nr_accept,
1361 .getname = nr_getname,
1362 .poll = datagram_poll,
1363 .ioctl = nr_ioctl,
1364 .gettstamp = sock_gettstamp,
1365 .listen = nr_listen,
1366 .shutdown = sock_no_shutdown,
1367 .setsockopt = nr_setsockopt,
1368 .getsockopt = nr_getsockopt,
1369 .sendmsg = nr_sendmsg,
1370 .recvmsg = nr_recvmsg,
1371 .mmap = sock_no_mmap,
1372};
1373
1374static struct notifier_block nr_dev_notifier = {
1375 .notifier_call = nr_device_event,
1376};
1377
1378static struct net_device **dev_nr;
1379
1380static struct ax25_protocol nr_pid = {
1381 .pid = AX25_P_NETROM,
1382 .func = nr_route_frame
1383};
1384
1385static struct ax25_linkfail nr_linkfail_notifier = {
1386 .func = nr_link_failed,
1387};
1388
1389static int __init nr_proto_init(void)
1390{
1391 int i;
1392 int rc = proto_register(&nr_proto, 0);
1393
1394 if (rc)
1395 return rc;
1396
1397 if (nr_ndevs > 0x7fffffff/sizeof(struct net_device *)) {
1398 pr_err("NET/ROM: %s - nr_ndevs parameter too large\n",
1399 __func__);
1400 rc = -EINVAL;
1401 goto unregister_proto;
1402 }
1403
1404 dev_nr = kcalloc(nr_ndevs, sizeof(struct net_device *), GFP_KERNEL);
1405 if (!dev_nr) {
1406 pr_err("NET/ROM: %s - unable to allocate device array\n",
1407 __func__);
1408 rc = -ENOMEM;
1409 goto unregister_proto;
1410 }
1411
1412 for (i = 0; i < nr_ndevs; i++) {
1413 char name[IFNAMSIZ];
1414 struct net_device *dev;
1415
1416 sprintf(name, "nr%d", i);
1417 dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, nr_setup);
1418 if (!dev) {
1419 rc = -ENOMEM;
1420 goto fail;
1421 }
1422
1423 dev->base_addr = i;
1424 rc = register_netdev(dev);
1425 if (rc) {
1426 free_netdev(dev);
1427 goto fail;
1428 }
1429 nr_set_lockdep_key(dev);
1430 dev_nr[i] = dev;
1431 }
1432
1433 rc = sock_register(&nr_family_ops);
1434 if (rc)
1435 goto fail;
1436
1437 rc = register_netdevice_notifier(&nr_dev_notifier);
1438 if (rc)
1439 goto out_sock;
1440
1441 ax25_register_pid(&nr_pid);
1442 ax25_linkfail_register(&nr_linkfail_notifier);
1443
1444#ifdef CONFIG_SYSCTL
1445 rc = nr_register_sysctl();
1446 if (rc)
1447 goto out_sysctl;
1448#endif
1449
1450 nr_loopback_init();
1451
1452 rc = -ENOMEM;
1453 if (!proc_create_seq("nr", 0444, init_net.proc_net, &nr_info_seqops))
1454 goto proc_remove1;
1455 if (!proc_create_seq("nr_neigh", 0444, init_net.proc_net,
1456 &nr_neigh_seqops))
1457 goto proc_remove2;
1458 if (!proc_create_seq("nr_nodes", 0444, init_net.proc_net,
1459 &nr_node_seqops))
1460 goto proc_remove3;
1461
1462 return 0;
1463
1464proc_remove3:
1465 remove_proc_entry("nr_neigh", init_net.proc_net);
1466proc_remove2:
1467 remove_proc_entry("nr", init_net.proc_net);
1468proc_remove1:
1469
1470 nr_loopback_clear();
1471 nr_rt_free();
1472
1473#ifdef CONFIG_SYSCTL
1474 nr_unregister_sysctl();
1475out_sysctl:
1476#endif
1477 ax25_linkfail_release(&nr_linkfail_notifier);
1478 ax25_protocol_release(AX25_P_NETROM);
1479 unregister_netdevice_notifier(&nr_dev_notifier);
1480out_sock:
1481 sock_unregister(PF_NETROM);
1482fail:
1483 while (--i >= 0) {
1484 unregister_netdev(dev_nr[i]);
1485 free_netdev(dev_nr[i]);
1486 }
1487 kfree(dev_nr);
1488unregister_proto:
1489 proto_unregister(&nr_proto);
1490 return rc;
1491}
1492
1493module_init(nr_proto_init);
1494
1495module_param(nr_ndevs, int, 0);
1496MODULE_PARM_DESC(nr_ndevs, "number of NET/ROM devices");
1497
1498MODULE_AUTHOR("Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>");
1499MODULE_DESCRIPTION("The amateur radio NET/ROM network and transport layer protocol");
1500MODULE_LICENSE("GPL");
1501MODULE_ALIAS_NETPROTO(PF_NETROM);
1502
1503static void __exit nr_exit(void)
1504{
1505 int i;
1506
1507 remove_proc_entry("nr", init_net.proc_net);
1508 remove_proc_entry("nr_neigh", init_net.proc_net);
1509 remove_proc_entry("nr_nodes", init_net.proc_net);
1510 nr_loopback_clear();
1511
1512 nr_rt_free();
1513
1514#ifdef CONFIG_SYSCTL
1515 nr_unregister_sysctl();
1516#endif
1517
1518 ax25_linkfail_release(&nr_linkfail_notifier);
1519 ax25_protocol_release(AX25_P_NETROM);
1520
1521 unregister_netdevice_notifier(&nr_dev_notifier);
1522
1523 sock_unregister(PF_NETROM);
1524
1525 for (i = 0; i < nr_ndevs; i++) {
1526 struct net_device *dev = dev_nr[i];
1527 if (dev) {
1528 unregister_netdev(dev);
1529 free_netdev(dev);
1530 }
1531 }
1532
1533 kfree(dev_nr);
1534 proto_unregister(&nr_proto);
1535}
1536module_exit(nr_exit);