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
60	int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
61	int sysctl_x25_call_request_timeout = X25_DEFAULT_T21;
62	int sysctl_x25_reset_request_timeout = X25_DEFAULT_T22;
63	int sysctl_x25_clear_request_timeout = X25_DEFAULT_T23;
64	int sysctl_x25_ack_holdback_timeout = X25_DEFAULT_T2;
65	int sysctl_x25_forward = 0;
66
67	HLIST_HEAD(x25_list);
68	DEFINE_RWLOCK(x25_list_lock);
69
70	static const struct proto_ops x25_proto_ops;
71
72	static const struct x25_address null_x25_address = {" "};
73
74	#ifdef CONFIG_COMPAT
75	struct 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
83	int 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, len: 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, len: 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
109	empty:
110	*called_addr->x25_addr = 0;
111	*calling_addr->x25_addr = 0;
112
113	return rc;
114	}
115
116
117	int 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
154	int 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	*/
195	static 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	* Handle device status changes.
204	*/
205	static int x25_device_event(struct notifier_block *this, unsigned long event,
206	void *ptr)
207	{
208	struct net_device *dev = netdev_notifier_info_to_dev(info: ptr);
209	struct x25_neigh *nb;
210
211	if (!net_eq(net1: dev_net(dev), net2: &init_net))
212	return NOTIFY_DONE;
213
214	if (dev->type == ARPHRD_X25) {
215	switch (event) {
216	case NETDEV_REGISTER:
217	case NETDEV_POST_TYPE_CHANGE:
218	x25_link_device_up(dev);
219	break;
220	case NETDEV_DOWN:
221	nb = x25_get_neigh(dev);
222	if (nb) {
223	x25_link_terminated(nb);
224	x25_neigh_put(nb);
225	}
226	x25_route_device_down(dev);
227	break;
228	case NETDEV_PRE_TYPE_CHANGE:
229	case NETDEV_UNREGISTER:
230	x25_link_device_down(dev);
231	break;
232	case NETDEV_CHANGE:
233	if (!netif_carrier_ok(dev)) {
234	nb = x25_get_neigh(dev);
235	if (nb) {
236	x25_link_terminated(nb);
237	x25_neigh_put(nb);
238	}
239	}
240	break;
241	}
242	}
243
244	return NOTIFY_DONE;
245	}
246
247	/*
248	* Add a socket to the bound sockets list.
249	*/
250	static void x25_insert_socket(struct sock *sk)
251	{
252	write_lock_bh(&x25_list_lock);
253	sk_add_node(sk, list: &x25_list);
254	write_unlock_bh(&x25_list_lock);
255	}
256
257	/*
258	* Find a socket that wants to accept the Call Request we just
259	* received. Check the full list for an address/cud match.
260	* If no cuds match return the next_best thing, an address match.
261	* Note: if a listening socket has cud set it must only get calls
262	* with matching cud.
263	*/
264	static struct sock *x25_find_listener(struct x25_address *addr,
265	struct sk_buff *skb)
266	{
267	struct sock *s;
268	struct sock *next_best;
269
270	read_lock_bh(&x25_list_lock);
271	next_best = NULL;
272
273	sk_for_each(s, &x25_list)
274	if ((!strcmp(addr->x25_addr,
275	x25_sk(s)->source_addr.x25_addr) ||
276	!strcmp(x25_sk(s)->source_addr.x25_addr,
277	null_x25_address.x25_addr)) &&
278	s->sk_state == TCP_LISTEN) {
279	/*
280	* Found a listening socket, now check the incoming
281	* call user data vs this sockets call user data
282	*/
283	if (x25_sk(s)->cudmatchlength > 0 &&
284	skb->len >= x25_sk(s)->cudmatchlength) {
285	if((memcmp(x25_sk(s)->calluserdata.cuddata,
286	q: skb->data,
287	x25_sk(s)->cudmatchlength)) == 0) {
288	sock_hold(sk: s);
289	goto found;
290	}
291	} else
292	next_best = s;
293	}
294	if (next_best) {
295	s = next_best;
296	sock_hold(sk: s);
297	goto found;
298	}
299	s = NULL;
300	found:
301	read_unlock_bh(&x25_list_lock);
302	return s;
303	}
304
305	/*
306	* Find a connected X.25 socket given my LCI and neighbour.
307	*/
308	static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
309	{
310	struct sock *s;
311
312	sk_for_each(s, &x25_list)
313	if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
314	sock_hold(sk: s);
315	goto found;
316	}
317	s = NULL;
318	found:
319	return s;
320	}
321
322	struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
323	{
324	struct sock *s;
325
326	read_lock_bh(&x25_list_lock);
327	s = __x25_find_socket(lci, nb);
328	read_unlock_bh(&x25_list_lock);
329	return s;
330	}
331
332	/*
333	* Find a unique LCI for a given device.
334	*/
335	static unsigned int x25_new_lci(struct x25_neigh *nb)
336	{
337	unsigned int lci = 1;
338	struct sock *sk;
339
340	while ((sk = x25_find_socket(lci, nb)) != NULL) {
341	sock_put(sk);
342	if (++lci == 4096) {
343	lci = 0;
344	break;
345	}
346	cond_resched();
347	}
348
349	return lci;
350	}
351
352	/*
353	* Deferred destroy.
354	*/
355	static void __x25_destroy_socket(struct sock *);
356
357	/*
358	* handler for deferred kills.
359	*/
360	static void x25_destroy_timer(struct timer_list *t)
361	{
362	struct sock *sk = from_timer(sk, t, sk_timer);
363
364	x25_destroy_socket_from_timer(sk);
365	}
366
367	/*
368	* This is called from user mode and the timers. Thus it protects itself
369	* against interrupting users but doesn't worry about being called during
370	* work. Once it is removed from the queue no interrupt or bottom half
371	* will touch it and we are (fairly 8-) ) safe.
372	* Not static as it's used by the timer
373	*/
374	static void __x25_destroy_socket(struct sock *sk)
375	{
376	struct sk_buff *skb;
377
378	x25_stop_heartbeat(sk);
379	x25_stop_timer(sk);
380
381	x25_remove_socket(sk);
382	x25_clear_queues(sk); /* Flush the queues */
383
384	while ((skb = skb_dequeue(list: &sk->sk_receive_queue)) != NULL) {
385	if (skb->sk != sk) { /* A pending connection */
386	/*
387	* Queue the unaccepted socket for death
388	*/
389	skb->sk->sk_state = TCP_LISTEN;
390	sock_set_flag(sk: skb->sk, flag: SOCK_DEAD);
391	x25_start_heartbeat(skb->sk);
392	x25_sk(skb->sk)->state = X25_STATE_0;
393	}
394
395	kfree_skb(skb);
396	}
397
398	if (sk_has_allocations(sk)) {
399	/* Defer: outstanding buffers */
400	sk->sk_timer.expires = jiffies + 10 * HZ;
401	sk->sk_timer.function = x25_destroy_timer;
402	add_timer(timer: &sk->sk_timer);
403	} else {
404	/* drop last reference so sock_put will free */
405	__sock_put(sk);
406	}
407	}
408
409	void x25_destroy_socket_from_timer(struct sock *sk)
410	{
411	sock_hold(sk);
412	bh_lock_sock(sk);
413	__x25_destroy_socket(sk);
414	bh_unlock_sock(sk);
415	sock_put(sk);
416	}
417
418	/*
419	* Handling for system calls applied via the various interfaces to a
420	* X.25 socket object.
421	*/
422
423	static int x25_setsockopt(struct socket *sock, int level, int optname,
424	sockptr_t optval, unsigned int optlen)
425	{
426	int opt;
427	struct sock *sk = sock->sk;
428	int rc = -ENOPROTOOPT;
429
430	if (level != SOL_X25 || optname != X25_QBITINCL)
431	goto out;
432
433	rc = -EINVAL;
434	if (optlen < sizeof(int))
435	goto out;
436
437	rc = -EFAULT;
438	if (copy_from_sockptr(dst: &opt, src: optval, size: sizeof(int)))
439	goto out;
440
441	if (opt)
442	set_bit(X25_Q_BIT_FLAG, addr: &x25_sk(sk)->flags);
443	else
444	clear_bit(X25_Q_BIT_FLAG, addr: &x25_sk(sk)->flags);
445	rc = 0;
446	out:
447	return rc;
448	}
449
450	static int x25_getsockopt(struct socket *sock, int level, int optname,
451	char __user *optval, int __user *optlen)
452	{
453	struct sock *sk = sock->sk;
454	int val, len, rc = -ENOPROTOOPT;
455
456	if (level != SOL_X25 || optname != X25_QBITINCL)
457	goto out;
458
459	rc = -EFAULT;
460	if (get_user(len, optlen))
461	goto out;
462
463	len = min_t(unsigned int, len, sizeof(int));
464
465	rc = -EINVAL;
466	if (len < 0)
467	goto out;
468
469	rc = -EFAULT;
470	if (put_user(len, optlen))
471	goto out;
472
473	val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
474	rc = copy_to_user(to: optval, from: &val, n: len) ? -EFAULT : 0;
475	out:
476	return rc;
477	}
478
479	static int x25_listen(struct socket *sock, int backlog)
480	{
481	struct sock *sk = sock->sk;
482	int rc = -EOPNOTSUPP;
483
484	lock_sock(sk);
485	if (sock->state != SS_UNCONNECTED) {
486	rc = -EINVAL;
487	release_sock(sk);
488	return rc;
489	}
490
491	if (sk->sk_state != TCP_LISTEN) {
492	memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
493	sk->sk_max_ack_backlog = backlog;
494	sk->sk_state = TCP_LISTEN;
495	rc = 0;
496	}
497	release_sock(sk);
498
499	return rc;
500	}
501
502	static struct proto x25_proto = {
503	.name = "X25",
504	.owner = THIS_MODULE,
505	.obj_size = sizeof(struct x25_sock),
506	};
507
508	static struct sock *x25_alloc_socket(struct net *net, int kern)
509	{
510	struct x25_sock *x25;
511	struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, prot: &x25_proto, kern);
512
513	if (!sk)
514	goto out;
515
516	sock_init_data(NULL, sk);
517
518	x25 = x25_sk(sk);
519	skb_queue_head_init(list: &x25->ack_queue);
520	skb_queue_head_init(list: &x25->fragment_queue);
521	skb_queue_head_init(list: &x25->interrupt_in_queue);
522	skb_queue_head_init(list: &x25->interrupt_out_queue);
523	out:
524	return sk;
525	}
526
527	static int x25_create(struct net *net, struct socket *sock, int protocol,
528	int kern)
529	{
530	struct sock *sk;
531	struct x25_sock *x25;
532	int rc = -EAFNOSUPPORT;
533
534	if (!net_eq(net1: net, net2: &init_net))
535	goto out;
536
537	rc = -ESOCKTNOSUPPORT;
538	if (sock->type != SOCK_SEQPACKET)
539	goto out;
540
541	rc = -EINVAL;
542	if (protocol)
543	goto out;
544
545	rc = -ENOMEM;
546	if ((sk = x25_alloc_socket(net, kern)) == NULL)
547	goto out;
548
549	x25 = x25_sk(sk);
550
551	sock_init_data(sock, sk);
552
553	x25_init_timers(sk);
554
555	sock->ops = &x25_proto_ops;
556	sk->sk_protocol = protocol;
557	sk->sk_backlog_rcv = x25_backlog_rcv;
558
559	x25->t21 = sysctl_x25_call_request_timeout;
560	x25->t22 = sysctl_x25_reset_request_timeout;
561	x25->t23 = sysctl_x25_clear_request_timeout;
562	x25->t2 = sysctl_x25_ack_holdback_timeout;
563	x25->state = X25_STATE_0;
564	x25->cudmatchlength = 0;
565	set_bit(X25_ACCPT_APPRV_FLAG, addr: &x25->flags); /* normally no cud */
566	/* on call accept */
567
568	x25->facilities.winsize_in = X25_DEFAULT_WINDOW_SIZE;
569	x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
570	x25->facilities.pacsize_in = X25_DEFAULT_PACKET_SIZE;
571	x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
572	x25->facilities.throughput = 0; /* by default don't negotiate
573	throughput */
574	x25->facilities.reverse = X25_DEFAULT_REVERSE;
575	x25->dte_facilities.calling_len = 0;
576	x25->dte_facilities.called_len = 0;
577	memset(x25->dte_facilities.called_ae, '\0',
578	sizeof(x25->dte_facilities.called_ae));
579	memset(x25->dte_facilities.calling_ae, '\0',
580	sizeof(x25->dte_facilities.calling_ae));
581
582	rc = 0;
583	out:
584	return rc;
585	}
586
587	static struct sock *x25_make_new(struct sock *osk)
588	{
589	struct sock *sk = NULL;
590	struct x25_sock *x25, *ox25;
591
592	if (osk->sk_type != SOCK_SEQPACKET)
593	goto out;
594
595	if ((sk = x25_alloc_socket(net: sock_net(sk: osk), kern: 0)) == NULL)
596	goto out;
597
598	x25 = x25_sk(sk);
599
600	sk->sk_type = osk->sk_type;
601	sk->sk_priority = READ_ONCE(osk->sk_priority);
602	sk->sk_protocol = osk->sk_protocol;
603	sk->sk_rcvbuf = osk->sk_rcvbuf;
604	sk->sk_sndbuf = osk->sk_sndbuf;
605	sk->sk_state = TCP_ESTABLISHED;
606	sk->sk_backlog_rcv = osk->sk_backlog_rcv;
607	sock_copy_flags(nsk: sk, osk);
608
609	ox25 = x25_sk(osk);
610	x25->t21 = ox25->t21;
611	x25->t22 = ox25->t22;
612	x25->t23 = ox25->t23;
613	x25->t2 = ox25->t2;
614	x25->flags = ox25->flags;
615	x25->facilities = ox25->facilities;
616	x25->dte_facilities = ox25->dte_facilities;
617	x25->cudmatchlength = ox25->cudmatchlength;
618
619	clear_bit(X25_INTERRUPT_FLAG, addr: &x25->flags);
620	x25_init_timers(sk);
621	out:
622	return sk;
623	}
624
625	static int x25_release(struct socket *sock)
626	{
627	struct sock *sk = sock->sk;
628	struct x25_sock *x25;
629
630	if (!sk)
631	return 0;
632
633	x25 = x25_sk(sk);
634
635	sock_hold(sk);
636	lock_sock(sk);
637	switch (x25->state) {
638
639	case X25_STATE_0:
640	case X25_STATE_2:
641	x25_disconnect(sk, 0, 0, 0);
642	__x25_destroy_socket(sk);
643	goto out;
644
645	case X25_STATE_1:
646	case X25_STATE_3:
647	case X25_STATE_4:
648	x25_clear_queues(sk);
649	x25_write_internal(sk, X25_CLEAR_REQUEST);
650	x25_start_t23timer(sk);
651	x25->state = X25_STATE_2;
652	sk->sk_state = TCP_CLOSE;
653	sk->sk_shutdown |= SEND_SHUTDOWN;
654	sk->sk_state_change(sk);
655	sock_set_flag(sk, flag: SOCK_DEAD);
656	sock_set_flag(sk, flag: SOCK_DESTROY);
657	break;
658
659	case X25_STATE_5:
660	x25_write_internal(sk, X25_CLEAR_REQUEST);
661	x25_disconnect(sk, 0, 0, 0);
662	__x25_destroy_socket(sk);
663	goto out;
664	}
665
666	sock_orphan(sk);
667	out:
668	release_sock(sk);
669	sock_put(sk);
670	return 0;
671	}
672
673	static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
674	{
675	struct sock *sk = sock->sk;
676	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
677	int len, i, rc = 0;
678
679	if (addr_len != sizeof(struct sockaddr_x25) ||
680	addr->sx25_family != AF_X25 ||
681	strnlen(p: addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) {
682	rc = -EINVAL;
683	goto out;
684	}
685
686	/* check for the null_x25_address */
687	if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
688
689	len = strlen(addr->sx25_addr.x25_addr);
690	for (i = 0; i < len; i++) {
691	if (!isdigit(c: addr->sx25_addr.x25_addr[i])) {
692	rc = -EINVAL;
693	goto out;
694	}
695	}
696	}
697
698	lock_sock(sk);
699	if (sock_flag(sk, flag: SOCK_ZAPPED)) {
700	x25_sk(sk)->source_addr = addr->sx25_addr;
701	x25_insert_socket(sk);
702	sock_reset_flag(sk, flag: SOCK_ZAPPED);
703	} else {
704	rc = -EINVAL;
705	}
706	release_sock(sk);
707	SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
708	out:
709	return rc;
710	}
711
712	static int x25_wait_for_connection_establishment(struct sock *sk)
713	{
714	DECLARE_WAITQUEUE(wait, current);
715	int rc;
716
717	add_wait_queue_exclusive(wq_head: sk_sleep(sk), wq_entry: &wait);
718	for (;;) {
719	__set_current_state(TASK_INTERRUPTIBLE);
720	rc = -ERESTARTSYS;
721	if (signal_pending(current))
722	break;
723	rc = sock_error(sk);
724	if (rc) {
725	sk->sk_socket->state = SS_UNCONNECTED;
726	break;
727	}
728	rc = -ENOTCONN;
729	if (sk->sk_state == TCP_CLOSE) {
730	sk->sk_socket->state = SS_UNCONNECTED;
731	break;
732	}
733	rc = 0;
734	if (sk->sk_state != TCP_ESTABLISHED) {
735	release_sock(sk);
736	schedule();
737	lock_sock(sk);
738	} else
739	break;
740	}
741	__set_current_state(TASK_RUNNING);
742	remove_wait_queue(wq_head: sk_sleep(sk), wq_entry: &wait);
743	return rc;
744	}
745
746	static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
747	int addr_len, int flags)
748	{
749	struct sock *sk = sock->sk;
750	struct x25_sock *x25 = x25_sk(sk);
751	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
752	struct x25_route *rt;
753	int rc = 0;
754
755	lock_sock(sk);
756	if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
757	sock->state = SS_CONNECTED;
758	goto out; /* Connect completed during a ERESTARTSYS event */
759	}
760
761	rc = -ECONNREFUSED;
762	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
763	sock->state = SS_UNCONNECTED;
764	goto out;
765	}
766
767	rc = -EISCONN; /* No reconnect on a seqpacket socket */
768	if (sk->sk_state == TCP_ESTABLISHED)
769	goto out;
770
771	rc = -EALREADY; /* Do nothing if call is already in progress */
772	if (sk->sk_state == TCP_SYN_SENT)
773	goto out;
774
775	sk->sk_state = TCP_CLOSE;
776	sock->state = SS_UNCONNECTED;
777
778	rc = -EINVAL;
779	if (addr_len != sizeof(struct sockaddr_x25) ||
780	addr->sx25_family != AF_X25 ||
781	strnlen(p: addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN)
782	goto out;
783
784	rc = -ENETUNREACH;
785	rt = x25_get_route(addr: &addr->sx25_addr);
786	if (!rt)
787	goto out;
788
789	x25->neighbour = x25_get_neigh(rt->dev);
790	if (!x25->neighbour)
791	goto out_put_route;
792
793	x25_limit_facilities(&x25->facilities, x25->neighbour);
794
795	x25->lci = x25_new_lci(nb: x25->neighbour);
796	if (!x25->lci)
797	goto out_put_neigh;
798
799	rc = -EINVAL;
800	if (sock_flag(sk, flag: SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
801	goto out_put_neigh;
802
803	if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
804	memset(&x25->source_addr, '\0', X25_ADDR_LEN);
805
806	x25->dest_addr = addr->sx25_addr;
807
808	/* Move to connecting socket, start sending Connect Requests */
809	sock->state = SS_CONNECTING;
810	sk->sk_state = TCP_SYN_SENT;
811
812	x25->state = X25_STATE_1;
813
814	x25_write_internal(sk, X25_CALL_REQUEST);
815
816	x25_start_heartbeat(sk);
817	x25_start_t21timer(sk);
818
819	/* Now the loop */
820	rc = -EINPROGRESS;
821	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
822	goto out;
823
824	rc = x25_wait_for_connection_establishment(sk);
825	if (rc)
826	goto out_put_neigh;
827
828	sock->state = SS_CONNECTED;
829	rc = 0;
830	out_put_neigh:
831	if (rc && x25->neighbour) {
832	read_lock_bh(&x25_list_lock);
833	x25_neigh_put(nb: x25->neighbour);
834	x25->neighbour = NULL;
835	read_unlock_bh(&x25_list_lock);
836	x25->state = X25_STATE_0;
837	}
838	out_put_route:
839	x25_route_put(rt);
840	out:
841	release_sock(sk);
842	return rc;
843	}
844
845	static int x25_wait_for_data(struct sock *sk, long timeout)
846	{
847	DECLARE_WAITQUEUE(wait, current);
848	int rc = 0;
849
850	add_wait_queue_exclusive(wq_head: sk_sleep(sk), wq_entry: &wait);
851	for (;;) {
852	__set_current_state(TASK_INTERRUPTIBLE);
853	if (sk->sk_shutdown & RCV_SHUTDOWN)
854	break;
855	rc = -ERESTARTSYS;
856	if (signal_pending(current))
857	break;
858	rc = -EAGAIN;
859	if (!timeout)
860	break;
861	rc = 0;
862	if (skb_queue_empty(list: &sk->sk_receive_queue)) {
863	release_sock(sk);
864	timeout = schedule_timeout(timeout);
865	lock_sock(sk);
866	} else
867	break;
868	}
869	__set_current_state(TASK_RUNNING);
870	remove_wait_queue(wq_head: sk_sleep(sk), wq_entry: &wait);
871	return rc;
872	}
873
874	static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
875	bool kern)
876	{
877	struct sock *sk = sock->sk;
878	struct sock *newsk;
879	struct sk_buff *skb;
880	int rc = -EINVAL;
881
882	if (!sk)
883	goto out;
884
885	rc = -EOPNOTSUPP;
886	if (sk->sk_type != SOCK_SEQPACKET)
887	goto out;
888
889	lock_sock(sk);
890	rc = -EINVAL;
891	if (sk->sk_state != TCP_LISTEN)
892	goto out2;
893
894	rc = x25_wait_for_data(sk, timeout: sk->sk_rcvtimeo);
895	if (rc)
896	goto out2;
897	skb = skb_dequeue(list: &sk->sk_receive_queue);
898	rc = -EINVAL;
899	if (!skb->sk)
900	goto out2;
901	newsk = skb->sk;
902	sock_graft(sk: newsk, parent: newsock);
903
904	/* Now attach up the new socket */
905	skb->sk = NULL;
906	kfree_skb(skb);
907	sk_acceptq_removed(sk);
908	newsock->state = SS_CONNECTED;
909	rc = 0;
910	out2:
911	release_sock(sk);
912	out:
913	return rc;
914	}
915
916	static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
917	int peer)
918	{
919	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
920	struct sock *sk = sock->sk;
921	struct x25_sock *x25 = x25_sk(sk);
922	int rc = 0;
923
924	if (peer) {
925	if (sk->sk_state != TCP_ESTABLISHED) {
926	rc = -ENOTCONN;
927	goto out;
928	}
929	sx25->sx25_addr = x25->dest_addr;
930	} else
931	sx25->sx25_addr = x25->source_addr;
932
933	sx25->sx25_family = AF_X25;
934	rc = sizeof(*sx25);
935
936	out:
937	return rc;
938	}
939
940	int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
941	unsigned int lci)
942	{
943	struct sock *sk;
944	struct sock *make;
945	struct x25_sock *makex25;
946	struct x25_address source_addr, dest_addr;
947	struct x25_facilities facilities;
948	struct x25_dte_facilities dte_facilities;
949	int len, addr_len, rc;
950
951	/*
952	* Remove the LCI and frame type.
953	*/
954	skb_pull(skb, X25_STD_MIN_LEN);
955
956	/*
957	* Extract the X.25 addresses and convert them to ASCII strings,
958	* and remove them.
959	*
960	* Address block is mandatory in call request packets
961	*/
962	addr_len = x25_parse_address_block(skb, called_addr: &source_addr, calling_addr: &dest_addr);
963	if (addr_len <= 0)
964	goto out_clear_request;
965	skb_pull(skb, len: addr_len);
966
967	/*
968	* Get the length of the facilities, skip past them for the moment
969	* get the call user data because this is needed to determine
970	* the correct listener
971	*
972	* Facilities length is mandatory in call request packets
973	*/
974	if (!pskb_may_pull(skb, len: 1))
975	goto out_clear_request;
976	len = skb->data[0] + 1;
977	if (!pskb_may_pull(skb, len))
978	goto out_clear_request;
979	skb_pull(skb,len);
980
981	/*
982	* Ensure that the amount of call user data is valid.
983	*/
984	if (skb->len > X25_MAX_CUD_LEN)
985	goto out_clear_request;
986
987	/*
988	* Get all the call user data so it can be used in
989	* x25_find_listener and skb_copy_from_linear_data up ahead.
990	*/
991	if (!pskb_may_pull(skb, len: skb->len))
992	goto out_clear_request;
993
994	/*
995	* Find a listener for the particular address/cud pair.
996	*/
997	sk = x25_find_listener(addr: &source_addr,skb);
998	skb_push(skb,len);
999
1000	if (sk != NULL && sk_acceptq_is_full(sk)) {
1001	goto out_sock_put;
1002	}
1003
1004	/*
1005	* We dont have any listeners for this incoming call.
1006	* Try forwarding it.
1007	*/
1008	if (sk == NULL) {
1009	skb_push(skb, len: addr_len + X25_STD_MIN_LEN);
1010	if (sysctl_x25_forward &&
1011	x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1012	{
1013	/* Call was forwarded, dont process it any more */
1014	kfree_skb(skb);
1015	rc = 1;
1016	goto out;
1017	} else {
1018	/* No listeners, can't forward, clear the call */
1019	goto out_clear_request;
1020	}
1021	}
1022
1023	/*
1024	* Try to reach a compromise on the requested facilities.
1025	*/
1026	len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1027	if (len == -1)
1028	goto out_sock_put;
1029
1030	/*
1031	* current neighbour/link might impose additional limits
1032	* on certain facilities
1033	*/
1034
1035	x25_limit_facilities(&facilities, nb);
1036
1037	/*
1038	* Try to create a new socket.
1039	*/
1040	make = x25_make_new(osk: sk);
1041	if (!make)
1042	goto out_sock_put;
1043
1044	/*
1045	* Remove the facilities
1046	*/
1047	skb_pull(skb, len);
1048
1049	skb->sk = make;
1050	make->sk_state = TCP_ESTABLISHED;
1051
1052	makex25 = x25_sk(make);
1053	makex25->lci = lci;
1054	makex25->dest_addr = dest_addr;
1055	makex25->source_addr = source_addr;
1056	x25_neigh_hold(nb);
1057	makex25->neighbour = nb;
1058	makex25->facilities = facilities;
1059	makex25->dte_facilities= dte_facilities;
1060	makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1061	/* ensure no reverse facil on accept */
1062	makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1063	/* ensure no calling address extension on accept */
1064	makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1065	makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1066
1067	/* Normally all calls are accepted immediately */
1068	if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1069	x25_write_internal(make, X25_CALL_ACCEPTED);
1070	makex25->state = X25_STATE_3;
1071	} else {
1072	makex25->state = X25_STATE_5;
1073	}
1074
1075	/*
1076	* Incoming Call User Data.
1077	*/
1078	skb_copy_from_linear_data(skb, to: makex25->calluserdata.cuddata, len: skb->len);
1079	makex25->calluserdata.cudlength = skb->len;
1080
1081	sk_acceptq_added(sk);
1082
1083	x25_insert_socket(sk: make);
1084
1085	skb_queue_head(list: &sk->sk_receive_queue, newsk: skb);
1086
1087	x25_start_heartbeat(make);
1088
1089	if (!sock_flag(sk, flag: SOCK_DEAD))
1090	sk->sk_data_ready(sk);
1091	rc = 1;
1092	sock_put(sk);
1093	out:
1094	return rc;
1095	out_sock_put:
1096	sock_put(sk);
1097	out_clear_request:
1098	rc = 0;
1099	x25_transmit_clear_request(nb, lci, 0x01);
1100	goto out;
1101	}
1102
1103	static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1104	{
1105	struct sock *sk = sock->sk;
1106	struct x25_sock *x25 = x25_sk(sk);
1107	DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1108	struct sockaddr_x25 sx25;
1109	struct sk_buff *skb;
1110	unsigned char *asmptr;
1111	int noblock = msg->msg_flags & MSG_DONTWAIT;
1112	size_t size;
1113	int qbit = 0, rc = -EINVAL;
1114
1115	lock_sock(sk);
1116	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1117	goto out;
1118
1119	/* we currently don't support segmented records at the user interface */
1120	if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1121	goto out;
1122
1123	rc = -EADDRNOTAVAIL;
1124	if (sock_flag(sk, flag: SOCK_ZAPPED))
1125	goto out;
1126
1127	rc = -EPIPE;
1128	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1129	send_sig(SIGPIPE, current, 0);
1130	goto out;
1131	}
1132
1133	rc = -ENETUNREACH;
1134	if (!x25->neighbour)
1135	goto out;
1136
1137	if (usx25) {
1138	rc = -EINVAL;
1139	if (msg->msg_namelen < sizeof(sx25))
1140	goto out;
1141	memcpy(&sx25, usx25, sizeof(sx25));
1142	rc = -EISCONN;
1143	if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1144	goto out;
1145	rc = -EINVAL;
1146	if (sx25.sx25_family != AF_X25)
1147	goto out;
1148	} else {
1149	/*
1150	* FIXME 1003.1g - if the socket is like this because
1151	* it has become closed (not started closed) we ought
1152	* to SIGPIPE, EPIPE;
1153	*/
1154	rc = -ENOTCONN;
1155	if (sk->sk_state != TCP_ESTABLISHED)
1156	goto out;
1157
1158	sx25.sx25_family = AF_X25;
1159	sx25.sx25_addr = x25->dest_addr;
1160	}
1161
1162	/* Sanity check the packet size */
1163	if (len > 65535) {
1164	rc = -EMSGSIZE;
1165	goto out;
1166	}
1167
1168	SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1169
1170	/* Build a packet */
1171	SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1172
1173	if ((msg->msg_flags & MSG_OOB) && len > 32)
1174	len = 32;
1175
1176	size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1177
1178	release_sock(sk);
1179	skb = sock_alloc_send_skb(sk, size, noblock, errcode: &rc);
1180	lock_sock(sk);
1181	if (!skb)
1182	goto out;
1183	X25_SKB_CB(skb)->flags = msg->msg_flags;
1184
1185	skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1186
1187	/*
1188	* Put the data on the end
1189	*/
1190	SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1191
1192	skb_reset_transport_header(skb);
1193	skb_put(skb, len);
1194
1195	rc = memcpy_from_msg(data: skb_transport_header(skb), msg, len);
1196	if (rc)
1197	goto out_kfree_skb;
1198
1199	/*
1200	* If the Q BIT Include socket option is in force, the first
1201	* byte of the user data is the logical value of the Q Bit.
1202	*/
1203	if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1204	if (!pskb_may_pull(skb, len: 1))
1205	goto out_kfree_skb;
1206
1207	qbit = skb->data[0];
1208	skb_pull(skb, len: 1);
1209	}
1210
1211	/*
1212	* Push down the X.25 header
1213	*/
1214	SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1215
1216	if (msg->msg_flags & MSG_OOB) {
1217	if (x25->neighbour->extended) {
1218	asmptr = skb_push(skb, X25_STD_MIN_LEN);
1219	*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1220	*asmptr++ = (x25->lci >> 0) & 0xFF;
1221	*asmptr++ = X25_INTERRUPT;
1222	} else {
1223	asmptr = skb_push(skb, X25_STD_MIN_LEN);
1224	*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1225	*asmptr++ = (x25->lci >> 0) & 0xFF;
1226	*asmptr++ = X25_INTERRUPT;
1227	}
1228	} else {
1229	if (x25->neighbour->extended) {
1230	/* Build an Extended X.25 header */
1231	asmptr = skb_push(skb, X25_EXT_MIN_LEN);
1232	*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1233	*asmptr++ = (x25->lci >> 0) & 0xFF;
1234	*asmptr++ = X25_DATA;
1235	*asmptr++ = X25_DATA;
1236	} else {
1237	/* Build an Standard X.25 header */
1238	asmptr = skb_push(skb, X25_STD_MIN_LEN);
1239	*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1240	*asmptr++ = (x25->lci >> 0) & 0xFF;
1241	*asmptr++ = X25_DATA;
1242	}
1243
1244	if (qbit)
1245	skb->data[0] |= X25_Q_BIT;
1246	}
1247
1248	SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1249	SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1250
1251	rc = -ENOTCONN;
1252	if (sk->sk_state != TCP_ESTABLISHED)
1253	goto out_kfree_skb;
1254
1255	if (msg->msg_flags & MSG_OOB)
1256	skb_queue_tail(list: &x25->interrupt_out_queue, newsk: skb);
1257	else {
1258	rc = x25_output(sk, skb);
1259	len = rc;
1260	if (rc < 0)
1261	kfree_skb(skb);
1262	else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1263	len++;
1264	}
1265
1266	x25_kick(sk);
1267	rc = len;
1268	out:
1269	release_sock(sk);
1270	return rc;
1271	out_kfree_skb:
1272	kfree_skb(skb);
1273	goto out;
1274	}
1275
1276
1277	static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1278	int flags)
1279	{
1280	struct sock *sk = sock->sk;
1281	struct x25_sock *x25 = x25_sk(sk);
1282	DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1283	size_t copied;
1284	int qbit, header_len;
1285	struct sk_buff *skb;
1286	unsigned char *asmptr;
1287	int rc = -ENOTCONN;
1288
1289	lock_sock(sk);
1290
1291	if (x25->neighbour == NULL)
1292	goto out;
1293
1294	header_len = x25->neighbour->extended ?
1295	X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1296
1297	/*
1298	* This works for seqpacket too. The receiver has ordered the queue for
1299	* us! We do one quick check first though
1300	*/
1301	if (sk->sk_state != TCP_ESTABLISHED)
1302	goto out;
1303
1304	if (flags & MSG_OOB) {
1305	rc = -EINVAL;
1306	if (sock_flag(sk, flag: SOCK_URGINLINE) ||
1307	!skb_peek(list_: &x25->interrupt_in_queue))
1308	goto out;
1309
1310	skb = skb_dequeue(list: &x25->interrupt_in_queue);
1311
1312	if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1313	goto out_free_dgram;
1314
1315	skb_pull(skb, X25_STD_MIN_LEN);
1316
1317	/*
1318	* No Q bit information on Interrupt data.
1319	*/
1320	if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1321	asmptr = skb_push(skb, len: 1);
1322	*asmptr = 0x00;
1323	}
1324
1325	msg->msg_flags |= MSG_OOB;
1326	} else {
1327	/* Now we can treat all alike */
1328	release_sock(sk);
1329	skb = skb_recv_datagram(sk, flags, err: &rc);
1330	lock_sock(sk);
1331	if (!skb)
1332	goto out;
1333
1334	if (!pskb_may_pull(skb, len: header_len))
1335	goto out_free_dgram;
1336
1337	qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1338
1339	skb_pull(skb, len: header_len);
1340
1341	if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1342	asmptr = skb_push(skb, len: 1);
1343	*asmptr = qbit;
1344	}
1345	}
1346
1347	skb_reset_transport_header(skb);
1348	copied = skb->len;
1349
1350	if (copied > size) {
1351	copied = size;
1352	msg->msg_flags |= MSG_TRUNC;
1353	}
1354
1355	/* Currently, each datagram always contains a complete record */
1356	msg->msg_flags |= MSG_EOR;
1357
1358	rc = skb_copy_datagram_msg(from: skb, offset: 0, msg, size: copied);
1359	if (rc)
1360	goto out_free_dgram;
1361
1362	if (sx25) {
1363	sx25->sx25_family = AF_X25;
1364	sx25->sx25_addr = x25->dest_addr;
1365	msg->msg_namelen = sizeof(*sx25);
1366	}
1367
1368	x25_check_rbuf(sk);
1369	rc = copied;
1370	out_free_dgram:
1371	skb_free_datagram(sk, skb);
1372	out:
1373	release_sock(sk);
1374	return rc;
1375	}
1376
1377
1378	static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1379	{
1380	struct sock *sk = sock->sk;
1381	struct x25_sock *x25 = x25_sk(sk);
1382	void __user *argp = (void __user *)arg;
1383	int rc;
1384
1385	switch (cmd) {
1386	case TIOCOUTQ: {
1387	int amount;
1388
1389	amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1390	if (amount < 0)
1391	amount = 0;
1392	rc = put_user(amount, (unsigned int __user *)argp);
1393	break;
1394	}
1395
1396	case TIOCINQ: {
1397	struct sk_buff *skb;
1398	int amount = 0;
1399	/*
1400	* These two are safe on a single CPU system as
1401	* only user tasks fiddle here
1402	*/
1403	lock_sock(sk);
1404	if ((skb = skb_peek(list_: &sk->sk_receive_queue)) != NULL)
1405	amount = skb->len;
1406	release_sock(sk);
1407	rc = put_user(amount, (unsigned int __user *)argp);
1408	break;
1409	}
1410
1411	case SIOCGIFADDR:
1412	case SIOCSIFADDR:
1413	case SIOCGIFDSTADDR:
1414	case SIOCSIFDSTADDR:
1415	case SIOCGIFBRDADDR:
1416	case SIOCSIFBRDADDR:
1417	case SIOCGIFNETMASK:
1418	case SIOCSIFNETMASK:
1419	case SIOCGIFMETRIC:
1420	case SIOCSIFMETRIC:
1421	rc = -EINVAL;
1422	break;
1423	case SIOCADDRT:
1424	case SIOCDELRT:
1425	rc = -EPERM;
1426	if (!capable(CAP_NET_ADMIN))
1427	break;
1428	rc = x25_route_ioctl(cmd, argp);
1429	break;
1430	case SIOCX25GSUBSCRIP:
1431	rc = x25_subscr_ioctl(cmd, argp);
1432	break;
1433	case SIOCX25SSUBSCRIP:
1434	rc = -EPERM;
1435	if (!capable(CAP_NET_ADMIN))
1436	break;
1437	rc = x25_subscr_ioctl(cmd, argp);
1438	break;
1439	case SIOCX25GFACILITIES: {
1440	lock_sock(sk);
1441	rc = copy_to_user(to: argp, from: &x25->facilities,
1442	n: sizeof(x25->facilities))
1443	? -EFAULT : 0;
1444	release_sock(sk);
1445	break;
1446	}
1447
1448	case SIOCX25SFACILITIES: {
1449	struct x25_facilities facilities;
1450	rc = -EFAULT;
1451	if (copy_from_user(to: &facilities, from: argp, n: sizeof(facilities)))
1452	break;
1453	rc = -EINVAL;
1454	lock_sock(sk);
1455	if (sk->sk_state != TCP_LISTEN &&
1456	sk->sk_state != TCP_CLOSE)
1457	goto out_fac_release;
1458	if (facilities.pacsize_in < X25_PS16 ||
1459	facilities.pacsize_in > X25_PS4096)
1460	goto out_fac_release;
1461	if (facilities.pacsize_out < X25_PS16 ||
1462	facilities.pacsize_out > X25_PS4096)
1463	goto out_fac_release;
1464	if (facilities.winsize_in < 1 ||
1465	facilities.winsize_in > 127)
1466	goto out_fac_release;
1467	if (facilities.throughput) {
1468	int out = facilities.throughput & 0xf0;
1469	int in = facilities.throughput & 0x0f;
1470	if (!out)
1471	facilities.throughput |=
1472	X25_DEFAULT_THROUGHPUT << 4;
1473	else if (out < 0x30 || out > 0xD0)
1474	goto out_fac_release;
1475	if (!in)
1476	facilities.throughput |=
1477	X25_DEFAULT_THROUGHPUT;
1478	else if (in < 0x03 || in > 0x0D)
1479	goto out_fac_release;
1480	}
1481	if (facilities.reverse &&
1482	(facilities.reverse & 0x81) != 0x81)
1483	goto out_fac_release;
1484	x25->facilities = facilities;
1485	rc = 0;
1486	out_fac_release:
1487	release_sock(sk);
1488	break;
1489	}
1490
1491	case SIOCX25GDTEFACILITIES: {
1492	lock_sock(sk);
1493	rc = copy_to_user(to: argp, from: &x25->dte_facilities,
1494	n: sizeof(x25->dte_facilities));
1495	release_sock(sk);
1496	if (rc)
1497	rc = -EFAULT;
1498	break;
1499	}
1500
1501	case SIOCX25SDTEFACILITIES: {
1502	struct x25_dte_facilities dtefacs;
1503	rc = -EFAULT;
1504	if (copy_from_user(to: &dtefacs, from: argp, n: sizeof(dtefacs)))
1505	break;
1506	rc = -EINVAL;
1507	lock_sock(sk);
1508	if (sk->sk_state != TCP_LISTEN &&
1509	sk->sk_state != TCP_CLOSE)
1510	goto out_dtefac_release;
1511	if (dtefacs.calling_len > X25_MAX_AE_LEN)
1512	goto out_dtefac_release;
1513	if (dtefacs.called_len > X25_MAX_AE_LEN)
1514	goto out_dtefac_release;
1515	x25->dte_facilities = dtefacs;
1516	rc = 0;
1517	out_dtefac_release:
1518	release_sock(sk);
1519	break;
1520	}
1521
1522	case SIOCX25GCALLUSERDATA: {
1523	lock_sock(sk);
1524	rc = copy_to_user(to: argp, from: &x25->calluserdata,
1525	n: sizeof(x25->calluserdata))
1526	? -EFAULT : 0;
1527	release_sock(sk);
1528	break;
1529	}
1530
1531	case SIOCX25SCALLUSERDATA: {
1532	struct x25_calluserdata calluserdata;
1533
1534	rc = -EFAULT;
1535	if (copy_from_user(to: &calluserdata, from: argp, n: sizeof(calluserdata)))
1536	break;
1537	rc = -EINVAL;
1538	if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1539	break;
1540	lock_sock(sk);
1541	x25->calluserdata = calluserdata;
1542	release_sock(sk);
1543	rc = 0;
1544	break;
1545	}
1546
1547	case SIOCX25GCAUSEDIAG: {
1548	lock_sock(sk);
1549	rc = copy_to_user(to: argp, from: &x25->causediag, n: sizeof(x25->causediag))
1550	? -EFAULT : 0;
1551	release_sock(sk);
1552	break;
1553	}
1554
1555	case SIOCX25SCAUSEDIAG: {
1556	struct x25_causediag causediag;
1557	rc = -EFAULT;
1558	if (copy_from_user(to: &causediag, from: argp, n: sizeof(causediag)))
1559	break;
1560	lock_sock(sk);
1561	x25->causediag = causediag;
1562	release_sock(sk);
1563	rc = 0;
1564	break;
1565
1566	}
1567
1568	case SIOCX25SCUDMATCHLEN: {
1569	struct x25_subaddr sub_addr;
1570	rc = -EINVAL;
1571	lock_sock(sk);
1572	if(sk->sk_state != TCP_CLOSE)
1573	goto out_cud_release;
1574	rc = -EFAULT;
1575	if (copy_from_user(to: &sub_addr, from: argp,
1576	n: sizeof(sub_addr)))
1577	goto out_cud_release;
1578	rc = -EINVAL;
1579	if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1580	goto out_cud_release;
1581	x25->cudmatchlength = sub_addr.cudmatchlength;
1582	rc = 0;
1583	out_cud_release:
1584	release_sock(sk);
1585	break;
1586	}
1587
1588	case SIOCX25CALLACCPTAPPRV: {
1589	rc = -EINVAL;
1590	lock_sock(sk);
1591	if (sk->sk_state == TCP_CLOSE) {
1592	clear_bit(X25_ACCPT_APPRV_FLAG, addr: &x25->flags);
1593	rc = 0;
1594	}
1595	release_sock(sk);
1596	break;
1597	}
1598
1599	case SIOCX25SENDCALLACCPT: {
1600	rc = -EINVAL;
1601	lock_sock(sk);
1602	if (sk->sk_state != TCP_ESTABLISHED)
1603	goto out_sendcallaccpt_release;
1604	/* must call accptapprv above */
1605	if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1606	goto out_sendcallaccpt_release;
1607	x25_write_internal(sk, X25_CALL_ACCEPTED);
1608	x25->state = X25_STATE_3;
1609	rc = 0;
1610	out_sendcallaccpt_release:
1611	release_sock(sk);
1612	break;
1613	}
1614
1615	default:
1616	rc = -ENOIOCTLCMD;
1617	break;
1618	}
1619
1620	return rc;
1621	}
1622
1623	static const struct net_proto_family x25_family_ops = {
1624	.family = AF_X25,
1625	.create = x25_create,
1626	.owner = THIS_MODULE,
1627	};
1628
1629	#ifdef CONFIG_COMPAT
1630	static int compat_x25_subscr_ioctl(unsigned int cmd,
1631	struct compat_x25_subscrip_struct __user *x25_subscr32)
1632	{
1633	struct compat_x25_subscrip_struct x25_subscr;
1634	struct x25_neigh *nb;
1635	struct net_device *dev;
1636	int rc = -EINVAL;
1637
1638	rc = -EFAULT;
1639	if (copy_from_user(to: &x25_subscr, from: x25_subscr32, n: sizeof(*x25_subscr32)))
1640	goto out;
1641
1642	rc = -EINVAL;
1643	dev = x25_dev_get(x25_subscr.device);
1644	if (dev == NULL)
1645	goto out;
1646
1647	nb = x25_get_neigh(dev);
1648	if (nb == NULL)
1649	goto out_dev_put;
1650
1651	dev_put(dev);
1652
1653	if (cmd == SIOCX25GSUBSCRIP) {
1654	read_lock_bh(&x25_neigh_list_lock);
1655	x25_subscr.extended = nb->extended;
1656	x25_subscr.global_facil_mask = nb->global_facil_mask;
1657	read_unlock_bh(&x25_neigh_list_lock);
1658	rc = copy_to_user(to: x25_subscr32, from: &x25_subscr,
1659	n: sizeof(*x25_subscr32)) ? -EFAULT : 0;
1660	} else {
1661	rc = -EINVAL;
1662	if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1663	rc = 0;
1664	write_lock_bh(&x25_neigh_list_lock);
1665	nb->extended = x25_subscr.extended;
1666	nb->global_facil_mask = x25_subscr.global_facil_mask;
1667	write_unlock_bh(&x25_neigh_list_lock);
1668	}
1669	}
1670	x25_neigh_put(nb);
1671	out:
1672	return rc;
1673	out_dev_put:
1674	dev_put(dev);
1675	goto out;
1676	}
1677
1678	static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1679	unsigned long arg)
1680	{
1681	void __user *argp = compat_ptr(uptr: arg);
1682	int rc = -ENOIOCTLCMD;
1683
1684	switch(cmd) {
1685	case TIOCOUTQ:
1686	case TIOCINQ:
1687	rc = x25_ioctl(sock, cmd, arg: (unsigned long)argp);
1688	break;
1689	case SIOCGIFADDR:
1690	case SIOCSIFADDR:
1691	case SIOCGIFDSTADDR:
1692	case SIOCSIFDSTADDR:
1693	case SIOCGIFBRDADDR:
1694	case SIOCSIFBRDADDR:
1695	case SIOCGIFNETMASK:
1696	case SIOCSIFNETMASK:
1697	case SIOCGIFMETRIC:
1698	case SIOCSIFMETRIC:
1699	rc = -EINVAL;
1700	break;
1701	case SIOCADDRT:
1702	case SIOCDELRT:
1703	rc = -EPERM;
1704	if (!capable(CAP_NET_ADMIN))
1705	break;
1706	rc = x25_route_ioctl(cmd, argp);
1707	break;
1708	case SIOCX25GSUBSCRIP:
1709	rc = compat_x25_subscr_ioctl(cmd, x25_subscr32: argp);
1710	break;
1711	case SIOCX25SSUBSCRIP:
1712	rc = -EPERM;
1713	if (!capable(CAP_NET_ADMIN))
1714	break;
1715	rc = compat_x25_subscr_ioctl(cmd, x25_subscr32: argp);
1716	break;
1717	case SIOCX25GFACILITIES:
1718	case SIOCX25SFACILITIES:
1719	case SIOCX25GDTEFACILITIES:
1720	case SIOCX25SDTEFACILITIES:
1721	case SIOCX25GCALLUSERDATA:
1722	case SIOCX25SCALLUSERDATA:
1723	case SIOCX25GCAUSEDIAG:
1724	case SIOCX25SCAUSEDIAG:
1725	case SIOCX25SCUDMATCHLEN:
1726	case SIOCX25CALLACCPTAPPRV:
1727	case SIOCX25SENDCALLACCPT:
1728	rc = x25_ioctl(sock, cmd, arg: (unsigned long)argp);
1729	break;
1730	default:
1731	rc = -ENOIOCTLCMD;
1732	break;
1733	}
1734	return rc;
1735	}
1736	#endif
1737
1738	static const struct proto_ops x25_proto_ops = {
1739	.family = AF_X25,
1740	.owner = THIS_MODULE,
1741	.release = x25_release,
1742	.bind = x25_bind,
1743	.connect = x25_connect,
1744	.socketpair = sock_no_socketpair,
1745	.accept = x25_accept,
1746	.getname = x25_getname,
1747	.poll = datagram_poll,
1748	.ioctl = x25_ioctl,
1749	#ifdef CONFIG_COMPAT
1750	.compat_ioctl = compat_x25_ioctl,
1751	#endif
1752	.gettstamp = sock_gettstamp,
1753	.listen = x25_listen,
1754	.shutdown = sock_no_shutdown,
1755	.setsockopt = x25_setsockopt,
1756	.getsockopt = x25_getsockopt,
1757	.sendmsg = x25_sendmsg,
1758	.recvmsg = x25_recvmsg,
1759	.mmap = sock_no_mmap,
1760	};
1761
1762	static struct packet_type x25_packet_type __read_mostly = {
1763	.type = cpu_to_be16(ETH_P_X25),
1764	.func = x25_lapb_receive_frame,
1765	};
1766
1767	static struct notifier_block x25_dev_notifier = {
1768	.notifier_call = x25_device_event,
1769	};
1770
1771	void x25_kill_by_neigh(struct x25_neigh *nb)
1772	{
1773	struct sock *s;
1774
1775	write_lock_bh(&x25_list_lock);
1776
1777	sk_for_each(s, &x25_list) {
1778	if (x25_sk(s)->neighbour == nb) {
1779	write_unlock_bh(&x25_list_lock);
1780	lock_sock(sk: s);
1781	x25_disconnect(s, ENETUNREACH, 0, 0);
1782	release_sock(sk: s);
1783	write_lock_bh(&x25_list_lock);
1784	}
1785	}
1786	write_unlock_bh(&x25_list_lock);
1787
1788	/* Remove any related forwards */
1789	x25_clear_forward_by_dev(nb->dev);
1790	}
1791
1792	static int __init x25_init(void)
1793	{
1794	int rc;
1795
1796	rc = proto_register(prot: &x25_proto, alloc_slab: 0);
1797	if (rc)
1798	goto out;
1799
1800	rc = sock_register(fam: &x25_family_ops);
1801	if (rc)
1802	goto out_proto;
1803
1804	dev_add_pack(pt: &x25_packet_type);
1805
1806	rc = register_netdevice_notifier(nb: &x25_dev_notifier);
1807	if (rc)
1808	goto out_sock;
1809
1810	rc = x25_register_sysctl();
1811	if (rc)
1812	goto out_dev;
1813
1814	rc = x25_proc_init();
1815	if (rc)
1816	goto out_sysctl;
1817
1818	pr_info("Linux Version 0.2\n");
1819
1820	out:
1821	return rc;
1822	out_sysctl:
1823	x25_unregister_sysctl();
1824	out_dev:
1825	unregister_netdevice_notifier(nb: &x25_dev_notifier);
1826	out_sock:
1827	dev_remove_pack(pt: &x25_packet_type);
1828	sock_unregister(AF_X25);
1829	out_proto:
1830	proto_unregister(prot: &x25_proto);
1831	goto out;
1832	}
1833	module_init(x25_init);
1834
1835	static void __exit x25_exit(void)
1836	{
1837	x25_proc_exit();
1838	x25_link_free();
1839	x25_route_free();
1840
1841	x25_unregister_sysctl();
1842
1843	unregister_netdevice_notifier(nb: &x25_dev_notifier);
1844
1845	dev_remove_pack(pt: &x25_packet_type);
1846
1847	sock_unregister(AF_X25);
1848	proto_unregister(prot: &x25_proto);
1849	}
1850	module_exit(x25_exit);
1851
1852	MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1853	MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1854	MODULE_LICENSE("GPL");
1855	MODULE_ALIAS_NETPROTO(PF_X25);
1856