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