xref: /kernel/linux/linux-5.10/net/x25/af_x25.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *	X.25 Packet Layer release 002
4 *
5 *	This is ALPHA test software. This code may break your machine,
6 *	randomly fail to work with new releases, misbehave and/or generally
7 *	screw up. It might even work.
8 *
9 *	This code REQUIRES 2.1.15 or higher
10 *
11 *	History
12 *	X.25 001	Jonathan Naylor	Started coding.
13 *	X.25 002	Jonathan Naylor	Centralised disconnect handling.
14 *					New timer architecture.
15 *	2000-03-11	Henner Eisen	MSG_EOR handling more POSIX compliant.
16 *	2000-03-22	Daniela Squassoni Allowed disabling/enabling of
17 *					  facilities negotiation and increased
18 *					  the throughput upper limit.
19 *	2000-08-27	Arnaldo C. Melo s/suser/capable/ + micro cleanups
20 *	2000-09-04	Henner Eisen	Set sock->state in x25_accept().
21 *					Fixed x25_output() related skb leakage.
22 *	2000-10-02	Henner Eisen	Made x25_kick() single threaded per socket.
23 *	2000-10-27	Henner Eisen    MSG_DONTWAIT for fragment allocation.
24 *	2000-11-14	Henner Eisen    Closing datalink from NETDEV_GOING_DOWN
25 *	2002-10-06	Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
26 *					x25_proc.c, using seq_file
27 *	2005-04-02	Shaun Pereira	Selective sub address matching
28 *					with call user data
29 *	2005-04-15	Shaun Pereira	Fast select with no restriction on
30 *					response
31 */
32
33#define pr_fmt(fmt) "X25: " fmt
34
35#include <linux/module.h>
36#include <linux/capability.h>
37#include <linux/errno.h>
38#include <linux/kernel.h>
39#include <linux/sched/signal.h>
40#include <linux/timer.h>
41#include <linux/string.h>
42#include <linux/net.h>
43#include <linux/netdevice.h>
44#include <linux/if_arp.h>
45#include <linux/skbuff.h>
46#include <linux/slab.h>
47#include <net/sock.h>
48#include <net/tcp_states.h>
49#include <linux/uaccess.h>
50#include <linux/fcntl.h>
51#include <linux/termios.h>	/* For TIOCINQ/OUTQ */
52#include <linux/notifier.h>
53#include <linux/init.h>
54#include <linux/compat.h>
55#include <linux/ctype.h>
56
57#include <net/x25.h>
58#include <net/compat.h>
59
60int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
61int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
62int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
63int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
64int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
65int sysctl_x25_forward                 = 0;
66
67HLIST_HEAD(x25_list);
68DEFINE_RWLOCK(x25_list_lock);
69
70static const struct proto_ops x25_proto_ops;
71
72static const struct x25_address null_x25_address = {"               "};
73
74#ifdef CONFIG_COMPAT
75struct compat_x25_subscrip_struct {
76	char device[200-sizeof(compat_ulong_t)];
77	compat_ulong_t global_facil_mask;
78	compat_uint_t extended;
79};
80#endif
81
82
83int x25_parse_address_block(struct sk_buff *skb,
84		struct x25_address *called_addr,
85		struct x25_address *calling_addr)
86{
87	unsigned char len;
88	int needed;
89	int rc;
90
91	if (!pskb_may_pull(skb, 1)) {
92		/* packet has no address block */
93		rc = 0;
94		goto empty;
95	}
96
97	len = *skb->data;
98	needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2;
99
100	if (!pskb_may_pull(skb, needed)) {
101		/* packet is too short to hold the addresses it claims
102		   to hold */
103		rc = -1;
104		goto empty;
105	}
106
107	return x25_addr_ntoa(skb->data, called_addr, calling_addr);
108
109empty:
110	*called_addr->x25_addr = 0;
111	*calling_addr->x25_addr = 0;
112
113	return rc;
114}
115
116
117int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
118		  struct x25_address *calling_addr)
119{
120	unsigned int called_len, calling_len;
121	char *called, *calling;
122	unsigned int i;
123
124	called_len  = (*p >> 0) & 0x0F;
125	calling_len = (*p >> 4) & 0x0F;
126
127	called  = called_addr->x25_addr;
128	calling = calling_addr->x25_addr;
129	p++;
130
131	for (i = 0; i < (called_len + calling_len); i++) {
132		if (i < called_len) {
133			if (i % 2 != 0) {
134				*called++ = ((*p >> 0) & 0x0F) + '0';
135				p++;
136			} else {
137				*called++ = ((*p >> 4) & 0x0F) + '0';
138			}
139		} else {
140			if (i % 2 != 0) {
141				*calling++ = ((*p >> 0) & 0x0F) + '0';
142				p++;
143			} else {
144				*calling++ = ((*p >> 4) & 0x0F) + '0';
145			}
146		}
147	}
148
149	*called = *calling = '\0';
150
151	return 1 + (called_len + calling_len + 1) / 2;
152}
153
154int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
155		  struct x25_address *calling_addr)
156{
157	unsigned int called_len, calling_len;
158	char *called, *calling;
159	int i;
160
161	called  = called_addr->x25_addr;
162	calling = calling_addr->x25_addr;
163
164	called_len  = strlen(called);
165	calling_len = strlen(calling);
166
167	*p++ = (calling_len << 4) | (called_len << 0);
168
169	for (i = 0; i < (called_len + calling_len); i++) {
170		if (i < called_len) {
171			if (i % 2 != 0) {
172				*p |= (*called++ - '0') << 0;
173				p++;
174			} else {
175				*p = 0x00;
176				*p |= (*called++ - '0') << 4;
177			}
178		} else {
179			if (i % 2 != 0) {
180				*p |= (*calling++ - '0') << 0;
181				p++;
182			} else {
183				*p = 0x00;
184				*p |= (*calling++ - '0') << 4;
185			}
186		}
187	}
188
189	return 1 + (called_len + calling_len + 1) / 2;
190}
191
192/*
193 *	Socket removal during an interrupt is now safe.
194 */
195static void x25_remove_socket(struct sock *sk)
196{
197	write_lock_bh(&x25_list_lock);
198	sk_del_node_init(sk);
199	write_unlock_bh(&x25_list_lock);
200}
201
202/*
203 *	Kill all bound sockets on a dropped device.
204 */
205static void x25_kill_by_device(struct net_device *dev)
206{
207	struct sock *s;
208
209	write_lock_bh(&x25_list_lock);
210
211	sk_for_each(s, &x25_list)
212		if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
213			x25_disconnect(s, ENETUNREACH, 0, 0);
214
215	write_unlock_bh(&x25_list_lock);
216}
217
218/*
219 *	Handle device status changes.
220 */
221static int x25_device_event(struct notifier_block *this, unsigned long event,
222			    void *ptr)
223{
224	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
225	struct x25_neigh *nb;
226
227	if (!net_eq(dev_net(dev), &init_net))
228		return NOTIFY_DONE;
229
230	if (dev->type == ARPHRD_X25
231#if IS_ENABLED(CONFIG_LLC)
232	 || dev->type == ARPHRD_ETHER
233#endif
234	 ) {
235		switch (event) {
236		case NETDEV_UP:
237			x25_link_device_up(dev);
238			break;
239		case NETDEV_GOING_DOWN:
240			nb = x25_get_neigh(dev);
241			if (nb) {
242				x25_terminate_link(nb);
243				x25_neigh_put(nb);
244			}
245			break;
246		case NETDEV_DOWN:
247			x25_kill_by_device(dev);
248			x25_route_device_down(dev);
249			x25_link_device_down(dev);
250			break;
251		}
252	}
253
254	return NOTIFY_DONE;
255}
256
257/*
258 *	Add a socket to the bound sockets list.
259 */
260static void x25_insert_socket(struct sock *sk)
261{
262	write_lock_bh(&x25_list_lock);
263	sk_add_node(sk, &x25_list);
264	write_unlock_bh(&x25_list_lock);
265}
266
267/*
268 *	Find a socket that wants to accept the Call Request we just
269 *	received. Check the full list for an address/cud match.
270 *	If no cuds match return the next_best thing, an address match.
271 *	Note: if a listening socket has cud set it must only get calls
272 *	with matching cud.
273 */
274static struct sock *x25_find_listener(struct x25_address *addr,
275					struct sk_buff *skb)
276{
277	struct sock *s;
278	struct sock *next_best;
279
280	read_lock_bh(&x25_list_lock);
281	next_best = NULL;
282
283	sk_for_each(s, &x25_list)
284		if ((!strcmp(addr->x25_addr,
285			x25_sk(s)->source_addr.x25_addr) ||
286				!strcmp(x25_sk(s)->source_addr.x25_addr,
287					null_x25_address.x25_addr)) &&
288					s->sk_state == TCP_LISTEN) {
289			/*
290			 * Found a listening socket, now check the incoming
291			 * call user data vs this sockets call user data
292			 */
293			if (x25_sk(s)->cudmatchlength > 0 &&
294				skb->len >= x25_sk(s)->cudmatchlength) {
295				if((memcmp(x25_sk(s)->calluserdata.cuddata,
296					skb->data,
297					x25_sk(s)->cudmatchlength)) == 0) {
298					sock_hold(s);
299					goto found;
300				 }
301			} else
302				next_best = s;
303		}
304	if (next_best) {
305		s = next_best;
306		sock_hold(s);
307		goto found;
308	}
309	s = NULL;
310found:
311	read_unlock_bh(&x25_list_lock);
312	return s;
313}
314
315/*
316 *	Find a connected X.25 socket given my LCI and neighbour.
317 */
318static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
319{
320	struct sock *s;
321
322	sk_for_each(s, &x25_list)
323		if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
324			sock_hold(s);
325			goto found;
326		}
327	s = NULL;
328found:
329	return s;
330}
331
332struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
333{
334	struct sock *s;
335
336	read_lock_bh(&x25_list_lock);
337	s = __x25_find_socket(lci, nb);
338	read_unlock_bh(&x25_list_lock);
339	return s;
340}
341
342/*
343 *	Find a unique LCI for a given device.
344 */
345static unsigned int x25_new_lci(struct x25_neigh *nb)
346{
347	unsigned int lci = 1;
348	struct sock *sk;
349
350	while ((sk = x25_find_socket(lci, nb)) != NULL) {
351		sock_put(sk);
352		if (++lci == 4096) {
353			lci = 0;
354			break;
355		}
356		cond_resched();
357	}
358
359	return lci;
360}
361
362/*
363 *	Deferred destroy.
364 */
365static void __x25_destroy_socket(struct sock *);
366
367/*
368 *	handler for deferred kills.
369 */
370static void x25_destroy_timer(struct timer_list *t)
371{
372	struct sock *sk = from_timer(sk, t, sk_timer);
373
374	x25_destroy_socket_from_timer(sk);
375}
376
377/*
378 *	This is called from user mode and the timers. Thus it protects itself
379 *	against interrupt users but doesn't worry about being called during
380 *	work. Once it is removed from the queue no interrupt or bottom half
381 *	will touch it and we are (fairly 8-) ) safe.
382 *	Not static as it's used by the timer
383 */
384static void __x25_destroy_socket(struct sock *sk)
385{
386	struct sk_buff *skb;
387
388	x25_stop_heartbeat(sk);
389	x25_stop_timer(sk);
390
391	x25_remove_socket(sk);
392	x25_clear_queues(sk);		/* Flush the queues */
393
394	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
395		if (skb->sk != sk) {		/* A pending connection */
396			/*
397			 * Queue the unaccepted socket for death
398			 */
399			skb->sk->sk_state = TCP_LISTEN;
400			sock_set_flag(skb->sk, SOCK_DEAD);
401			x25_start_heartbeat(skb->sk);
402			x25_sk(skb->sk)->state = X25_STATE_0;
403		}
404
405		kfree_skb(skb);
406	}
407
408	if (sk_has_allocations(sk)) {
409		/* Defer: outstanding buffers */
410		sk->sk_timer.expires  = jiffies + 10 * HZ;
411		sk->sk_timer.function = x25_destroy_timer;
412		add_timer(&sk->sk_timer);
413	} else {
414		/* drop last reference so sock_put will free */
415		__sock_put(sk);
416	}
417}
418
419void x25_destroy_socket_from_timer(struct sock *sk)
420{
421	sock_hold(sk);
422	bh_lock_sock(sk);
423	__x25_destroy_socket(sk);
424	bh_unlock_sock(sk);
425	sock_put(sk);
426}
427
428/*
429 *	Handling for system calls applied via the various interfaces to a
430 *	X.25 socket object.
431 */
432
433static int x25_setsockopt(struct socket *sock, int level, int optname,
434			  sockptr_t optval, unsigned int optlen)
435{
436	int opt;
437	struct sock *sk = sock->sk;
438	int rc = -ENOPROTOOPT;
439
440	if (level != SOL_X25 || optname != X25_QBITINCL)
441		goto out;
442
443	rc = -EINVAL;
444	if (optlen < sizeof(int))
445		goto out;
446
447	rc = -EFAULT;
448	if (copy_from_sockptr(&opt, optval, sizeof(int)))
449		goto out;
450
451	if (opt)
452		set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
453	else
454		clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
455	rc = 0;
456out:
457	return rc;
458}
459
460static int x25_getsockopt(struct socket *sock, int level, int optname,
461			  char __user *optval, int __user *optlen)
462{
463	struct sock *sk = sock->sk;
464	int val, len, rc = -ENOPROTOOPT;
465
466	if (level != SOL_X25 || optname != X25_QBITINCL)
467		goto out;
468
469	rc = -EFAULT;
470	if (get_user(len, optlen))
471		goto out;
472
473	len = min_t(unsigned int, len, sizeof(int));
474
475	rc = -EINVAL;
476	if (len < 0)
477		goto out;
478
479	rc = -EFAULT;
480	if (put_user(len, optlen))
481		goto out;
482
483	val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
484	rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
485out:
486	return rc;
487}
488
489static int x25_listen(struct socket *sock, int backlog)
490{
491	struct sock *sk = sock->sk;
492	int rc = -EOPNOTSUPP;
493
494	lock_sock(sk);
495	if (sock->state != SS_UNCONNECTED) {
496		rc = -EINVAL;
497		release_sock(sk);
498		return rc;
499	}
500
501	if (sk->sk_state != TCP_LISTEN) {
502		memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
503		sk->sk_max_ack_backlog = backlog;
504		sk->sk_state           = TCP_LISTEN;
505		rc = 0;
506	}
507	release_sock(sk);
508
509	return rc;
510}
511
512static struct proto x25_proto = {
513	.name	  = "X25",
514	.owner	  = THIS_MODULE,
515	.obj_size = sizeof(struct x25_sock),
516};
517
518static struct sock *x25_alloc_socket(struct net *net, int kern)
519{
520	struct x25_sock *x25;
521	struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
522
523	if (!sk)
524		goto out;
525
526	sock_init_data(NULL, sk);
527
528	x25 = x25_sk(sk);
529	skb_queue_head_init(&x25->ack_queue);
530	skb_queue_head_init(&x25->fragment_queue);
531	skb_queue_head_init(&x25->interrupt_in_queue);
532	skb_queue_head_init(&x25->interrupt_out_queue);
533out:
534	return sk;
535}
536
537static int x25_create(struct net *net, struct socket *sock, int protocol,
538		      int kern)
539{
540	struct sock *sk;
541	struct x25_sock *x25;
542	int rc = -EAFNOSUPPORT;
543
544	if (!net_eq(net, &init_net))
545		goto out;
546
547	rc = -ESOCKTNOSUPPORT;
548	if (sock->type != SOCK_SEQPACKET)
549		goto out;
550
551	rc = -EINVAL;
552	if (protocol)
553		goto out;
554
555	rc = -ENOMEM;
556	if ((sk = x25_alloc_socket(net, kern)) == NULL)
557		goto out;
558
559	x25 = x25_sk(sk);
560
561	sock_init_data(sock, sk);
562
563	x25_init_timers(sk);
564
565	sock->ops    = &x25_proto_ops;
566	sk->sk_protocol = protocol;
567	sk->sk_backlog_rcv = x25_backlog_rcv;
568
569	x25->t21   = sysctl_x25_call_request_timeout;
570	x25->t22   = sysctl_x25_reset_request_timeout;
571	x25->t23   = sysctl_x25_clear_request_timeout;
572	x25->t2    = sysctl_x25_ack_holdback_timeout;
573	x25->state = X25_STATE_0;
574	x25->cudmatchlength = 0;
575	set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);	/* normally no cud  */
576							/* on call accept   */
577
578	x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
579	x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
580	x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
581	x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
582	x25->facilities.throughput  = 0;	/* by default don't negotiate
583						   throughput */
584	x25->facilities.reverse     = X25_DEFAULT_REVERSE;
585	x25->dte_facilities.calling_len = 0;
586	x25->dte_facilities.called_len = 0;
587	memset(x25->dte_facilities.called_ae, '\0',
588			sizeof(x25->dte_facilities.called_ae));
589	memset(x25->dte_facilities.calling_ae, '\0',
590			sizeof(x25->dte_facilities.calling_ae));
591
592	rc = 0;
593out:
594	return rc;
595}
596
597static struct sock *x25_make_new(struct sock *osk)
598{
599	struct sock *sk = NULL;
600	struct x25_sock *x25, *ox25;
601
602	if (osk->sk_type != SOCK_SEQPACKET)
603		goto out;
604
605	if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
606		goto out;
607
608	x25 = x25_sk(sk);
609
610	sk->sk_type        = osk->sk_type;
611	sk->sk_priority    = osk->sk_priority;
612	sk->sk_protocol    = osk->sk_protocol;
613	sk->sk_rcvbuf      = osk->sk_rcvbuf;
614	sk->sk_sndbuf      = osk->sk_sndbuf;
615	sk->sk_state       = TCP_ESTABLISHED;
616	sk->sk_backlog_rcv = osk->sk_backlog_rcv;
617	sock_copy_flags(sk, osk);
618
619	ox25 = x25_sk(osk);
620	x25->t21        = ox25->t21;
621	x25->t22        = ox25->t22;
622	x25->t23        = ox25->t23;
623	x25->t2         = ox25->t2;
624	x25->flags	= ox25->flags;
625	x25->facilities = ox25->facilities;
626	x25->dte_facilities = ox25->dte_facilities;
627	x25->cudmatchlength = ox25->cudmatchlength;
628
629	clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
630	x25_init_timers(sk);
631out:
632	return sk;
633}
634
635static int x25_release(struct socket *sock)
636{
637	struct sock *sk = sock->sk;
638	struct x25_sock *x25;
639
640	if (!sk)
641		return 0;
642
643	x25 = x25_sk(sk);
644
645	sock_hold(sk);
646	lock_sock(sk);
647	switch (x25->state) {
648
649		case X25_STATE_0:
650		case X25_STATE_2:
651			x25_disconnect(sk, 0, 0, 0);
652			__x25_destroy_socket(sk);
653			goto out;
654
655		case X25_STATE_1:
656		case X25_STATE_3:
657		case X25_STATE_4:
658			x25_clear_queues(sk);
659			x25_write_internal(sk, X25_CLEAR_REQUEST);
660			x25_start_t23timer(sk);
661			x25->state = X25_STATE_2;
662			sk->sk_state	= TCP_CLOSE;
663			sk->sk_shutdown	|= SEND_SHUTDOWN;
664			sk->sk_state_change(sk);
665			sock_set_flag(sk, SOCK_DEAD);
666			sock_set_flag(sk, SOCK_DESTROY);
667			break;
668
669		case X25_STATE_5:
670			x25_write_internal(sk, X25_CLEAR_REQUEST);
671			x25_disconnect(sk, 0, 0, 0);
672			__x25_destroy_socket(sk);
673			goto out;
674	}
675
676	sock_orphan(sk);
677out:
678	release_sock(sk);
679	sock_put(sk);
680	return 0;
681}
682
683static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
684{
685	struct sock *sk = sock->sk;
686	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
687	int len, i, rc = 0;
688
689	if (addr_len != sizeof(struct sockaddr_x25) ||
690	    addr->sx25_family != AF_X25 ||
691	    strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) {
692		rc = -EINVAL;
693		goto out;
694	}
695
696	/* check for the null_x25_address */
697	if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
698
699		len = strlen(addr->sx25_addr.x25_addr);
700		for (i = 0; i < len; i++) {
701			if (!isdigit(addr->sx25_addr.x25_addr[i])) {
702				rc = -EINVAL;
703				goto out;
704			}
705		}
706	}
707
708	lock_sock(sk);
709	if (sock_flag(sk, SOCK_ZAPPED)) {
710		x25_sk(sk)->source_addr = addr->sx25_addr;
711		x25_insert_socket(sk);
712		sock_reset_flag(sk, SOCK_ZAPPED);
713	} else {
714		rc = -EINVAL;
715	}
716	release_sock(sk);
717	SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
718out:
719	return rc;
720}
721
722static int x25_wait_for_connection_establishment(struct sock *sk)
723{
724	DECLARE_WAITQUEUE(wait, current);
725	int rc;
726
727	add_wait_queue_exclusive(sk_sleep(sk), &wait);
728	for (;;) {
729		__set_current_state(TASK_INTERRUPTIBLE);
730		rc = -ERESTARTSYS;
731		if (signal_pending(current))
732			break;
733		rc = sock_error(sk);
734		if (rc) {
735			sk->sk_socket->state = SS_UNCONNECTED;
736			break;
737		}
738		rc = 0;
739		if (sk->sk_state != TCP_ESTABLISHED) {
740			release_sock(sk);
741			schedule();
742			lock_sock(sk);
743		} else
744			break;
745	}
746	__set_current_state(TASK_RUNNING);
747	remove_wait_queue(sk_sleep(sk), &wait);
748	return rc;
749}
750
751static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
752		       int addr_len, int flags)
753{
754	struct sock *sk = sock->sk;
755	struct x25_sock *x25 = x25_sk(sk);
756	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
757	struct x25_route *rt;
758	int rc = 0;
759
760	lock_sock(sk);
761	if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
762		sock->state = SS_CONNECTED;
763		goto out; /* Connect completed during a ERESTARTSYS event */
764	}
765
766	rc = -ECONNREFUSED;
767	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
768		sock->state = SS_UNCONNECTED;
769		goto out;
770	}
771
772	rc = -EISCONN;	/* No reconnect on a seqpacket socket */
773	if (sk->sk_state == TCP_ESTABLISHED)
774		goto out;
775
776	rc = -EALREADY;	/* Do nothing if call is already in progress */
777	if (sk->sk_state == TCP_SYN_SENT)
778		goto out;
779
780	sk->sk_state   = TCP_CLOSE;
781	sock->state = SS_UNCONNECTED;
782
783	rc = -EINVAL;
784	if (addr_len != sizeof(struct sockaddr_x25) ||
785	    addr->sx25_family != AF_X25 ||
786	    strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN)
787		goto out;
788
789	rc = -ENETUNREACH;
790	rt = x25_get_route(&addr->sx25_addr);
791	if (!rt)
792		goto out;
793
794	x25->neighbour = x25_get_neigh(rt->dev);
795	if (!x25->neighbour)
796		goto out_put_route;
797
798	x25_limit_facilities(&x25->facilities, x25->neighbour);
799
800	x25->lci = x25_new_lci(x25->neighbour);
801	if (!x25->lci)
802		goto out_put_neigh;
803
804	rc = -EINVAL;
805	if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
806		goto out_put_neigh;
807
808	if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
809		memset(&x25->source_addr, '\0', X25_ADDR_LEN);
810
811	x25->dest_addr = addr->sx25_addr;
812
813	/* Move to connecting socket, start sending Connect Requests */
814	sock->state   = SS_CONNECTING;
815	sk->sk_state  = TCP_SYN_SENT;
816
817	x25->state = X25_STATE_1;
818
819	x25_write_internal(sk, X25_CALL_REQUEST);
820
821	x25_start_heartbeat(sk);
822	x25_start_t21timer(sk);
823
824	/* Now the loop */
825	rc = -EINPROGRESS;
826	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
827		goto out;
828
829	rc = x25_wait_for_connection_establishment(sk);
830	if (rc)
831		goto out_put_neigh;
832
833	sock->state = SS_CONNECTED;
834	rc = 0;
835out_put_neigh:
836	if (rc && x25->neighbour) {
837		read_lock_bh(&x25_list_lock);
838		x25_neigh_put(x25->neighbour);
839		x25->neighbour = NULL;
840		read_unlock_bh(&x25_list_lock);
841		x25->state = X25_STATE_0;
842	}
843out_put_route:
844	x25_route_put(rt);
845out:
846	release_sock(sk);
847	return rc;
848}
849
850static int x25_wait_for_data(struct sock *sk, long timeout)
851{
852	DECLARE_WAITQUEUE(wait, current);
853	int rc = 0;
854
855	add_wait_queue_exclusive(sk_sleep(sk), &wait);
856	for (;;) {
857		__set_current_state(TASK_INTERRUPTIBLE);
858		if (sk->sk_shutdown & RCV_SHUTDOWN)
859			break;
860		rc = -ERESTARTSYS;
861		if (signal_pending(current))
862			break;
863		rc = -EAGAIN;
864		if (!timeout)
865			break;
866		rc = 0;
867		if (skb_queue_empty(&sk->sk_receive_queue)) {
868			release_sock(sk);
869			timeout = schedule_timeout(timeout);
870			lock_sock(sk);
871		} else
872			break;
873	}
874	__set_current_state(TASK_RUNNING);
875	remove_wait_queue(sk_sleep(sk), &wait);
876	return rc;
877}
878
879static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
880		      bool kern)
881{
882	struct sock *sk = sock->sk;
883	struct sock *newsk;
884	struct sk_buff *skb;
885	int rc = -EINVAL;
886
887	if (!sk)
888		goto out;
889
890	rc = -EOPNOTSUPP;
891	if (sk->sk_type != SOCK_SEQPACKET)
892		goto out;
893
894	lock_sock(sk);
895	rc = -EINVAL;
896	if (sk->sk_state != TCP_LISTEN)
897		goto out2;
898
899	rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
900	if (rc)
901		goto out2;
902	skb = skb_dequeue(&sk->sk_receive_queue);
903	rc = -EINVAL;
904	if (!skb->sk)
905		goto out2;
906	newsk		 = skb->sk;
907	sock_graft(newsk, newsock);
908
909	/* Now attach up the new socket */
910	skb->sk = NULL;
911	kfree_skb(skb);
912	sk_acceptq_removed(sk);
913	newsock->state = SS_CONNECTED;
914	rc = 0;
915out2:
916	release_sock(sk);
917out:
918	return rc;
919}
920
921static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
922		       int peer)
923{
924	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
925	struct sock *sk = sock->sk;
926	struct x25_sock *x25 = x25_sk(sk);
927	int rc = 0;
928
929	if (peer) {
930		if (sk->sk_state != TCP_ESTABLISHED) {
931			rc = -ENOTCONN;
932			goto out;
933		}
934		sx25->sx25_addr = x25->dest_addr;
935	} else
936		sx25->sx25_addr = x25->source_addr;
937
938	sx25->sx25_family = AF_X25;
939	rc = sizeof(*sx25);
940
941out:
942	return rc;
943}
944
945int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
946			unsigned int lci)
947{
948	struct sock *sk;
949	struct sock *make;
950	struct x25_sock *makex25;
951	struct x25_address source_addr, dest_addr;
952	struct x25_facilities facilities;
953	struct x25_dte_facilities dte_facilities;
954	int len, addr_len, rc;
955
956	/*
957	 *	Remove the LCI and frame type.
958	 */
959	skb_pull(skb, X25_STD_MIN_LEN);
960
961	/*
962	 *	Extract the X.25 addresses and convert them to ASCII strings,
963	 *	and remove them.
964	 *
965	 *	Address block is mandatory in call request packets
966	 */
967	addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
968	if (addr_len <= 0)
969		goto out_clear_request;
970	skb_pull(skb, addr_len);
971
972	/*
973	 *	Get the length of the facilities, skip past them for the moment
974	 *	get the call user data because this is needed to determine
975	 *	the correct listener
976	 *
977	 *	Facilities length is mandatory in call request packets
978	 */
979	if (!pskb_may_pull(skb, 1))
980		goto out_clear_request;
981	len = skb->data[0] + 1;
982	if (!pskb_may_pull(skb, len))
983		goto out_clear_request;
984	skb_pull(skb,len);
985
986	/*
987	 *	Ensure that the amount of call user data is valid.
988	 */
989	if (skb->len > X25_MAX_CUD_LEN)
990		goto out_clear_request;
991
992	/*
993	 *	Get all the call user data so it can be used in
994	 *	x25_find_listener and skb_copy_from_linear_data up ahead.
995	 */
996	if (!pskb_may_pull(skb, skb->len))
997		goto out_clear_request;
998
999	/*
1000	 *	Find a listener for the particular address/cud pair.
1001	 */
1002	sk = x25_find_listener(&source_addr,skb);
1003	skb_push(skb,len);
1004
1005	if (sk != NULL && sk_acceptq_is_full(sk)) {
1006		goto out_sock_put;
1007	}
1008
1009	/*
1010	 *	We dont have any listeners for this incoming call.
1011	 *	Try forwarding it.
1012	 */
1013	if (sk == NULL) {
1014		skb_push(skb, addr_len + X25_STD_MIN_LEN);
1015		if (sysctl_x25_forward &&
1016				x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1017		{
1018			/* Call was forwarded, dont process it any more */
1019			kfree_skb(skb);
1020			rc = 1;
1021			goto out;
1022		} else {
1023			/* No listeners, can't forward, clear the call */
1024			goto out_clear_request;
1025		}
1026	}
1027
1028	/*
1029	 *	Try to reach a compromise on the requested facilities.
1030	 */
1031	len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1032	if (len == -1)
1033		goto out_sock_put;
1034
1035	/*
1036	 * current neighbour/link might impose additional limits
1037	 * on certain facilties
1038	 */
1039
1040	x25_limit_facilities(&facilities, nb);
1041
1042	/*
1043	 *	Try to create a new socket.
1044	 */
1045	make = x25_make_new(sk);
1046	if (!make)
1047		goto out_sock_put;
1048
1049	/*
1050	 *	Remove the facilities
1051	 */
1052	skb_pull(skb, len);
1053
1054	skb->sk     = make;
1055	make->sk_state = TCP_ESTABLISHED;
1056
1057	makex25 = x25_sk(make);
1058	makex25->lci           = lci;
1059	makex25->dest_addr     = dest_addr;
1060	makex25->source_addr   = source_addr;
1061	x25_neigh_hold(nb);
1062	makex25->neighbour     = nb;
1063	makex25->facilities    = facilities;
1064	makex25->dte_facilities= dte_facilities;
1065	makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1066	/* ensure no reverse facil on accept */
1067	makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1068	/* ensure no calling address extension on accept */
1069	makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1070	makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1071
1072	/* Normally all calls are accepted immediately */
1073	if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1074		x25_write_internal(make, X25_CALL_ACCEPTED);
1075		makex25->state = X25_STATE_3;
1076	} else {
1077		makex25->state = X25_STATE_5;
1078	}
1079
1080	/*
1081	 *	Incoming Call User Data.
1082	 */
1083	skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1084	makex25->calluserdata.cudlength = skb->len;
1085
1086	sk_acceptq_added(sk);
1087
1088	x25_insert_socket(make);
1089
1090	skb_queue_head(&sk->sk_receive_queue, skb);
1091
1092	x25_start_heartbeat(make);
1093
1094	if (!sock_flag(sk, SOCK_DEAD))
1095		sk->sk_data_ready(sk);
1096	rc = 1;
1097	sock_put(sk);
1098out:
1099	return rc;
1100out_sock_put:
1101	sock_put(sk);
1102out_clear_request:
1103	rc = 0;
1104	x25_transmit_clear_request(nb, lci, 0x01);
1105	goto out;
1106}
1107
1108static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1109{
1110	struct sock *sk = sock->sk;
1111	struct x25_sock *x25 = x25_sk(sk);
1112	DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1113	struct sockaddr_x25 sx25;
1114	struct sk_buff *skb;
1115	unsigned char *asmptr;
1116	int noblock = msg->msg_flags & MSG_DONTWAIT;
1117	size_t size;
1118	int qbit = 0, rc = -EINVAL;
1119
1120	lock_sock(sk);
1121	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1122		goto out;
1123
1124	/* we currently don't support segmented records at the user interface */
1125	if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1126		goto out;
1127
1128	rc = -EADDRNOTAVAIL;
1129	if (sock_flag(sk, SOCK_ZAPPED))
1130		goto out;
1131
1132	rc = -EPIPE;
1133	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1134		send_sig(SIGPIPE, current, 0);
1135		goto out;
1136	}
1137
1138	rc = -ENETUNREACH;
1139	if (!x25->neighbour)
1140		goto out;
1141
1142	if (usx25) {
1143		rc = -EINVAL;
1144		if (msg->msg_namelen < sizeof(sx25))
1145			goto out;
1146		memcpy(&sx25, usx25, sizeof(sx25));
1147		rc = -EISCONN;
1148		if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1149			goto out;
1150		rc = -EINVAL;
1151		if (sx25.sx25_family != AF_X25)
1152			goto out;
1153	} else {
1154		/*
1155		 *	FIXME 1003.1g - if the socket is like this because
1156		 *	it has become closed (not started closed) we ought
1157		 *	to SIGPIPE, EPIPE;
1158		 */
1159		rc = -ENOTCONN;
1160		if (sk->sk_state != TCP_ESTABLISHED)
1161			goto out;
1162
1163		sx25.sx25_family = AF_X25;
1164		sx25.sx25_addr   = x25->dest_addr;
1165	}
1166
1167	/* Sanity check the packet size */
1168	if (len > 65535) {
1169		rc = -EMSGSIZE;
1170		goto out;
1171	}
1172
1173	SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1174
1175	/* Build a packet */
1176	SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1177
1178	if ((msg->msg_flags & MSG_OOB) && len > 32)
1179		len = 32;
1180
1181	size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1182
1183	release_sock(sk);
1184	skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1185	lock_sock(sk);
1186	if (!skb)
1187		goto out;
1188	X25_SKB_CB(skb)->flags = msg->msg_flags;
1189
1190	skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1191
1192	/*
1193	 *	Put the data on the end
1194	 */
1195	SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1196
1197	skb_reset_transport_header(skb);
1198	skb_put(skb, len);
1199
1200	rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1201	if (rc)
1202		goto out_kfree_skb;
1203
1204	/*
1205	 *	If the Q BIT Include socket option is in force, the first
1206	 *	byte of the user data is the logical value of the Q Bit.
1207	 */
1208	if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1209		if (!pskb_may_pull(skb, 1))
1210			goto out_kfree_skb;
1211
1212		qbit = skb->data[0];
1213		skb_pull(skb, 1);
1214	}
1215
1216	/*
1217	 *	Push down the X.25 header
1218	 */
1219	SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1220
1221	if (msg->msg_flags & MSG_OOB) {
1222		if (x25->neighbour->extended) {
1223			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1224			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1225			*asmptr++ = (x25->lci >> 0) & 0xFF;
1226			*asmptr++ = X25_INTERRUPT;
1227		} else {
1228			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1229			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1230			*asmptr++ = (x25->lci >> 0) & 0xFF;
1231			*asmptr++ = X25_INTERRUPT;
1232		}
1233	} else {
1234		if (x25->neighbour->extended) {
1235			/* Build an Extended X.25 header */
1236			asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1237			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1238			*asmptr++ = (x25->lci >> 0) & 0xFF;
1239			*asmptr++ = X25_DATA;
1240			*asmptr++ = X25_DATA;
1241		} else {
1242			/* Build an Standard X.25 header */
1243			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1244			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1245			*asmptr++ = (x25->lci >> 0) & 0xFF;
1246			*asmptr++ = X25_DATA;
1247		}
1248
1249		if (qbit)
1250			skb->data[0] |= X25_Q_BIT;
1251	}
1252
1253	SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1254	SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1255
1256	rc = -ENOTCONN;
1257	if (sk->sk_state != TCP_ESTABLISHED)
1258		goto out_kfree_skb;
1259
1260	if (msg->msg_flags & MSG_OOB)
1261		skb_queue_tail(&x25->interrupt_out_queue, skb);
1262	else {
1263		rc = x25_output(sk, skb);
1264		len = rc;
1265		if (rc < 0)
1266			kfree_skb(skb);
1267		else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1268			len++;
1269	}
1270
1271	x25_kick(sk);
1272	rc = len;
1273out:
1274	release_sock(sk);
1275	return rc;
1276out_kfree_skb:
1277	kfree_skb(skb);
1278	goto out;
1279}
1280
1281
1282static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1283		       int flags)
1284{
1285	struct sock *sk = sock->sk;
1286	struct x25_sock *x25 = x25_sk(sk);
1287	DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1288	size_t copied;
1289	int qbit, header_len;
1290	struct sk_buff *skb;
1291	unsigned char *asmptr;
1292	int rc = -ENOTCONN;
1293
1294	lock_sock(sk);
1295
1296	if (x25->neighbour == NULL)
1297		goto out;
1298
1299	header_len = x25->neighbour->extended ?
1300		X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1301
1302	/*
1303	 * This works for seqpacket too. The receiver has ordered the queue for
1304	 * us! We do one quick check first though
1305	 */
1306	if (sk->sk_state != TCP_ESTABLISHED)
1307		goto out;
1308
1309	if (flags & MSG_OOB) {
1310		rc = -EINVAL;
1311		if (sock_flag(sk, SOCK_URGINLINE) ||
1312		    !skb_peek(&x25->interrupt_in_queue))
1313			goto out;
1314
1315		skb = skb_dequeue(&x25->interrupt_in_queue);
1316
1317		if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1318			goto out_free_dgram;
1319
1320		skb_pull(skb, X25_STD_MIN_LEN);
1321
1322		/*
1323		 *	No Q bit information on Interrupt data.
1324		 */
1325		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1326			asmptr  = skb_push(skb, 1);
1327			*asmptr = 0x00;
1328		}
1329
1330		msg->msg_flags |= MSG_OOB;
1331	} else {
1332		/* Now we can treat all alike */
1333		release_sock(sk);
1334		skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1335					flags & MSG_DONTWAIT, &rc);
1336		lock_sock(sk);
1337		if (!skb)
1338			goto out;
1339
1340		if (!pskb_may_pull(skb, header_len))
1341			goto out_free_dgram;
1342
1343		qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1344
1345		skb_pull(skb, header_len);
1346
1347		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1348			asmptr  = skb_push(skb, 1);
1349			*asmptr = qbit;
1350		}
1351	}
1352
1353	skb_reset_transport_header(skb);
1354	copied = skb->len;
1355
1356	if (copied > size) {
1357		copied = size;
1358		msg->msg_flags |= MSG_TRUNC;
1359	}
1360
1361	/* Currently, each datagram always contains a complete record */
1362	msg->msg_flags |= MSG_EOR;
1363
1364	rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1365	if (rc)
1366		goto out_free_dgram;
1367
1368	if (sx25) {
1369		sx25->sx25_family = AF_X25;
1370		sx25->sx25_addr   = x25->dest_addr;
1371		msg->msg_namelen = sizeof(*sx25);
1372	}
1373
1374	x25_check_rbuf(sk);
1375	rc = copied;
1376out_free_dgram:
1377	skb_free_datagram(sk, skb);
1378out:
1379	release_sock(sk);
1380	return rc;
1381}
1382
1383
1384static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1385{
1386	struct sock *sk = sock->sk;
1387	struct x25_sock *x25 = x25_sk(sk);
1388	void __user *argp = (void __user *)arg;
1389	int rc;
1390
1391	switch (cmd) {
1392	case TIOCOUTQ: {
1393		int amount;
1394
1395		amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1396		if (amount < 0)
1397			amount = 0;
1398		rc = put_user(amount, (unsigned int __user *)argp);
1399		break;
1400	}
1401
1402	case TIOCINQ: {
1403		struct sk_buff *skb;
1404		int amount = 0;
1405		/*
1406		 * These two are safe on a single CPU system as
1407		 * only user tasks fiddle here
1408		 */
1409		lock_sock(sk);
1410		if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1411			amount = skb->len;
1412		release_sock(sk);
1413		rc = put_user(amount, (unsigned int __user *)argp);
1414		break;
1415	}
1416
1417	case SIOCGIFADDR:
1418	case SIOCSIFADDR:
1419	case SIOCGIFDSTADDR:
1420	case SIOCSIFDSTADDR:
1421	case SIOCGIFBRDADDR:
1422	case SIOCSIFBRDADDR:
1423	case SIOCGIFNETMASK:
1424	case SIOCSIFNETMASK:
1425	case SIOCGIFMETRIC:
1426	case SIOCSIFMETRIC:
1427		rc = -EINVAL;
1428		break;
1429	case SIOCADDRT:
1430	case SIOCDELRT:
1431		rc = -EPERM;
1432		if (!capable(CAP_NET_ADMIN))
1433			break;
1434		rc = x25_route_ioctl(cmd, argp);
1435		break;
1436	case SIOCX25GSUBSCRIP:
1437		rc = x25_subscr_ioctl(cmd, argp);
1438		break;
1439	case SIOCX25SSUBSCRIP:
1440		rc = -EPERM;
1441		if (!capable(CAP_NET_ADMIN))
1442			break;
1443		rc = x25_subscr_ioctl(cmd, argp);
1444		break;
1445	case SIOCX25GFACILITIES: {
1446		lock_sock(sk);
1447		rc = copy_to_user(argp, &x25->facilities,
1448				  sizeof(x25->facilities))
1449			? -EFAULT : 0;
1450		release_sock(sk);
1451		break;
1452	}
1453
1454	case SIOCX25SFACILITIES: {
1455		struct x25_facilities facilities;
1456		rc = -EFAULT;
1457		if (copy_from_user(&facilities, argp, sizeof(facilities)))
1458			break;
1459		rc = -EINVAL;
1460		lock_sock(sk);
1461		if (sk->sk_state != TCP_LISTEN &&
1462		    sk->sk_state != TCP_CLOSE)
1463			goto out_fac_release;
1464		if (facilities.pacsize_in < X25_PS16 ||
1465		    facilities.pacsize_in > X25_PS4096)
1466			goto out_fac_release;
1467		if (facilities.pacsize_out < X25_PS16 ||
1468		    facilities.pacsize_out > X25_PS4096)
1469			goto out_fac_release;
1470		if (facilities.winsize_in < 1 ||
1471		    facilities.winsize_in > 127)
1472			goto out_fac_release;
1473		if (facilities.throughput) {
1474			int out = facilities.throughput & 0xf0;
1475			int in  = facilities.throughput & 0x0f;
1476			if (!out)
1477				facilities.throughput |=
1478					X25_DEFAULT_THROUGHPUT << 4;
1479			else if (out < 0x30 || out > 0xD0)
1480				goto out_fac_release;
1481			if (!in)
1482				facilities.throughput |=
1483					X25_DEFAULT_THROUGHPUT;
1484			else if (in < 0x03 || in > 0x0D)
1485				goto out_fac_release;
1486		}
1487		if (facilities.reverse &&
1488		    (facilities.reverse & 0x81) != 0x81)
1489			goto out_fac_release;
1490		x25->facilities = facilities;
1491		rc = 0;
1492out_fac_release:
1493		release_sock(sk);
1494		break;
1495	}
1496
1497	case SIOCX25GDTEFACILITIES: {
1498		lock_sock(sk);
1499		rc = copy_to_user(argp, &x25->dte_facilities,
1500				  sizeof(x25->dte_facilities));
1501		release_sock(sk);
1502		if (rc)
1503			rc = -EFAULT;
1504		break;
1505	}
1506
1507	case SIOCX25SDTEFACILITIES: {
1508		struct x25_dte_facilities dtefacs;
1509		rc = -EFAULT;
1510		if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1511			break;
1512		rc = -EINVAL;
1513		lock_sock(sk);
1514		if (sk->sk_state != TCP_LISTEN &&
1515		    sk->sk_state != TCP_CLOSE)
1516			goto out_dtefac_release;
1517		if (dtefacs.calling_len > X25_MAX_AE_LEN)
1518			goto out_dtefac_release;
1519		if (dtefacs.called_len > X25_MAX_AE_LEN)
1520			goto out_dtefac_release;
1521		x25->dte_facilities = dtefacs;
1522		rc = 0;
1523out_dtefac_release:
1524		release_sock(sk);
1525		break;
1526	}
1527
1528	case SIOCX25GCALLUSERDATA: {
1529		lock_sock(sk);
1530		rc = copy_to_user(argp, &x25->calluserdata,
1531				  sizeof(x25->calluserdata))
1532			? -EFAULT : 0;
1533		release_sock(sk);
1534		break;
1535	}
1536
1537	case SIOCX25SCALLUSERDATA: {
1538		struct x25_calluserdata calluserdata;
1539
1540		rc = -EFAULT;
1541		if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1542			break;
1543		rc = -EINVAL;
1544		if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1545			break;
1546		lock_sock(sk);
1547		x25->calluserdata = calluserdata;
1548		release_sock(sk);
1549		rc = 0;
1550		break;
1551	}
1552
1553	case SIOCX25GCAUSEDIAG: {
1554		lock_sock(sk);
1555		rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1556			? -EFAULT : 0;
1557		release_sock(sk);
1558		break;
1559	}
1560
1561	case SIOCX25SCAUSEDIAG: {
1562		struct x25_causediag causediag;
1563		rc = -EFAULT;
1564		if (copy_from_user(&causediag, argp, sizeof(causediag)))
1565			break;
1566		lock_sock(sk);
1567		x25->causediag = causediag;
1568		release_sock(sk);
1569		rc = 0;
1570		break;
1571
1572	}
1573
1574	case SIOCX25SCUDMATCHLEN: {
1575		struct x25_subaddr sub_addr;
1576		rc = -EINVAL;
1577		lock_sock(sk);
1578		if(sk->sk_state != TCP_CLOSE)
1579			goto out_cud_release;
1580		rc = -EFAULT;
1581		if (copy_from_user(&sub_addr, argp,
1582				   sizeof(sub_addr)))
1583			goto out_cud_release;
1584		rc = -EINVAL;
1585		if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1586			goto out_cud_release;
1587		x25->cudmatchlength = sub_addr.cudmatchlength;
1588		rc = 0;
1589out_cud_release:
1590		release_sock(sk);
1591		break;
1592	}
1593
1594	case SIOCX25CALLACCPTAPPRV: {
1595		rc = -EINVAL;
1596		lock_sock(sk);
1597		if (sk->sk_state == TCP_CLOSE) {
1598			clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1599			rc = 0;
1600		}
1601		release_sock(sk);
1602		break;
1603	}
1604
1605	case SIOCX25SENDCALLACCPT:  {
1606		rc = -EINVAL;
1607		lock_sock(sk);
1608		if (sk->sk_state != TCP_ESTABLISHED)
1609			goto out_sendcallaccpt_release;
1610		/* must call accptapprv above */
1611		if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1612			goto out_sendcallaccpt_release;
1613		x25_write_internal(sk, X25_CALL_ACCEPTED);
1614		x25->state = X25_STATE_3;
1615		rc = 0;
1616out_sendcallaccpt_release:
1617		release_sock(sk);
1618		break;
1619	}
1620
1621	default:
1622		rc = -ENOIOCTLCMD;
1623		break;
1624	}
1625
1626	return rc;
1627}
1628
1629static const struct net_proto_family x25_family_ops = {
1630	.family =	AF_X25,
1631	.create =	x25_create,
1632	.owner	=	THIS_MODULE,
1633};
1634
1635#ifdef CONFIG_COMPAT
1636static int compat_x25_subscr_ioctl(unsigned int cmd,
1637		struct compat_x25_subscrip_struct __user *x25_subscr32)
1638{
1639	struct compat_x25_subscrip_struct x25_subscr;
1640	struct x25_neigh *nb;
1641	struct net_device *dev;
1642	int rc = -EINVAL;
1643
1644	rc = -EFAULT;
1645	if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1646		goto out;
1647
1648	rc = -EINVAL;
1649	dev = x25_dev_get(x25_subscr.device);
1650	if (dev == NULL)
1651		goto out;
1652
1653	nb = x25_get_neigh(dev);
1654	if (nb == NULL)
1655		goto out_dev_put;
1656
1657	dev_put(dev);
1658
1659	if (cmd == SIOCX25GSUBSCRIP) {
1660		read_lock_bh(&x25_neigh_list_lock);
1661		x25_subscr.extended = nb->extended;
1662		x25_subscr.global_facil_mask = nb->global_facil_mask;
1663		read_unlock_bh(&x25_neigh_list_lock);
1664		rc = copy_to_user(x25_subscr32, &x25_subscr,
1665				sizeof(*x25_subscr32)) ? -EFAULT : 0;
1666	} else {
1667		rc = -EINVAL;
1668		if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1669			rc = 0;
1670			write_lock_bh(&x25_neigh_list_lock);
1671			nb->extended = x25_subscr.extended;
1672			nb->global_facil_mask = x25_subscr.global_facil_mask;
1673			write_unlock_bh(&x25_neigh_list_lock);
1674		}
1675	}
1676	x25_neigh_put(nb);
1677out:
1678	return rc;
1679out_dev_put:
1680	dev_put(dev);
1681	goto out;
1682}
1683
1684static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1685				unsigned long arg)
1686{
1687	void __user *argp = compat_ptr(arg);
1688	int rc = -ENOIOCTLCMD;
1689
1690	switch(cmd) {
1691	case TIOCOUTQ:
1692	case TIOCINQ:
1693		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1694		break;
1695	case SIOCGIFADDR:
1696	case SIOCSIFADDR:
1697	case SIOCGIFDSTADDR:
1698	case SIOCSIFDSTADDR:
1699	case SIOCGIFBRDADDR:
1700	case SIOCSIFBRDADDR:
1701	case SIOCGIFNETMASK:
1702	case SIOCSIFNETMASK:
1703	case SIOCGIFMETRIC:
1704	case SIOCSIFMETRIC:
1705		rc = -EINVAL;
1706		break;
1707	case SIOCADDRT:
1708	case SIOCDELRT:
1709		rc = -EPERM;
1710		if (!capable(CAP_NET_ADMIN))
1711			break;
1712		rc = x25_route_ioctl(cmd, argp);
1713		break;
1714	case SIOCX25GSUBSCRIP:
1715		rc = compat_x25_subscr_ioctl(cmd, argp);
1716		break;
1717	case SIOCX25SSUBSCRIP:
1718		rc = -EPERM;
1719		if (!capable(CAP_NET_ADMIN))
1720			break;
1721		rc = compat_x25_subscr_ioctl(cmd, argp);
1722		break;
1723	case SIOCX25GFACILITIES:
1724	case SIOCX25SFACILITIES:
1725	case SIOCX25GDTEFACILITIES:
1726	case SIOCX25SDTEFACILITIES:
1727	case SIOCX25GCALLUSERDATA:
1728	case SIOCX25SCALLUSERDATA:
1729	case SIOCX25GCAUSEDIAG:
1730	case SIOCX25SCAUSEDIAG:
1731	case SIOCX25SCUDMATCHLEN:
1732	case SIOCX25CALLACCPTAPPRV:
1733	case SIOCX25SENDCALLACCPT:
1734		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1735		break;
1736	default:
1737		rc = -ENOIOCTLCMD;
1738		break;
1739	}
1740	return rc;
1741}
1742#endif
1743
1744static const struct proto_ops x25_proto_ops = {
1745	.family =	AF_X25,
1746	.owner =	THIS_MODULE,
1747	.release =	x25_release,
1748	.bind =		x25_bind,
1749	.connect =	x25_connect,
1750	.socketpair =	sock_no_socketpair,
1751	.accept =	x25_accept,
1752	.getname =	x25_getname,
1753	.poll =		datagram_poll,
1754	.ioctl =	x25_ioctl,
1755#ifdef CONFIG_COMPAT
1756	.compat_ioctl = compat_x25_ioctl,
1757#endif
1758	.gettstamp =	sock_gettstamp,
1759	.listen =	x25_listen,
1760	.shutdown =	sock_no_shutdown,
1761	.setsockopt =	x25_setsockopt,
1762	.getsockopt =	x25_getsockopt,
1763	.sendmsg =	x25_sendmsg,
1764	.recvmsg =	x25_recvmsg,
1765	.mmap =		sock_no_mmap,
1766	.sendpage =	sock_no_sendpage,
1767};
1768
1769static struct packet_type x25_packet_type __read_mostly = {
1770	.type =	cpu_to_be16(ETH_P_X25),
1771	.func =	x25_lapb_receive_frame,
1772};
1773
1774static struct notifier_block x25_dev_notifier = {
1775	.notifier_call = x25_device_event,
1776};
1777
1778void x25_kill_by_neigh(struct x25_neigh *nb)
1779{
1780	struct sock *s;
1781
1782	write_lock_bh(&x25_list_lock);
1783
1784	sk_for_each(s, &x25_list) {
1785		if (x25_sk(s)->neighbour == nb) {
1786			write_unlock_bh(&x25_list_lock);
1787			lock_sock(s);
1788			x25_disconnect(s, ENETUNREACH, 0, 0);
1789			release_sock(s);
1790			write_lock_bh(&x25_list_lock);
1791		}
1792	}
1793	write_unlock_bh(&x25_list_lock);
1794
1795	/* Remove any related forwards */
1796	x25_clear_forward_by_dev(nb->dev);
1797}
1798
1799static int __init x25_init(void)
1800{
1801	int rc;
1802
1803	rc = proto_register(&x25_proto, 0);
1804	if (rc)
1805		goto out;
1806
1807	rc = sock_register(&x25_family_ops);
1808	if (rc)
1809		goto out_proto;
1810
1811	dev_add_pack(&x25_packet_type);
1812
1813	rc = register_netdevice_notifier(&x25_dev_notifier);
1814	if (rc)
1815		goto out_sock;
1816
1817	rc = x25_register_sysctl();
1818	if (rc)
1819		goto out_dev;
1820
1821	rc = x25_proc_init();
1822	if (rc)
1823		goto out_sysctl;
1824
1825	pr_info("Linux Version 0.2\n");
1826
1827out:
1828	return rc;
1829out_sysctl:
1830	x25_unregister_sysctl();
1831out_dev:
1832	unregister_netdevice_notifier(&x25_dev_notifier);
1833out_sock:
1834	dev_remove_pack(&x25_packet_type);
1835	sock_unregister(AF_X25);
1836out_proto:
1837	proto_unregister(&x25_proto);
1838	goto out;
1839}
1840module_init(x25_init);
1841
1842static void __exit x25_exit(void)
1843{
1844	x25_proc_exit();
1845	x25_link_free();
1846	x25_route_free();
1847
1848	x25_unregister_sysctl();
1849
1850	unregister_netdevice_notifier(&x25_dev_notifier);
1851
1852	dev_remove_pack(&x25_packet_type);
1853
1854	sock_unregister(AF_X25);
1855	proto_unregister(&x25_proto);
1856}
1857module_exit(x25_exit);
1858
1859MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1860MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1861MODULE_LICENSE("GPL");
1862MODULE_ALIAS_NETPROTO(PF_X25);
1863