xref: /openbmc/linux/net/x25/af_x25.c (revision 95e9fd10)
1 /*
2  *	X.25 Packet Layer release 002
3  *
4  *	This is ALPHA test software. This code may break your machine,
5  *	randomly fail to work with new releases, misbehave and/or generally
6  *	screw up. It might even work.
7  *
8  *	This code REQUIRES 2.1.15 or higher
9  *
10  *	This module:
11  *		This module is free software; you can redistribute it and/or
12  *		modify it under the terms of the GNU General Public License
13  *		as published by the Free Software Foundation; either version
14  *		2 of the License, or (at your option) any later version.
15  *
16  *	History
17  *	X.25 001	Jonathan Naylor	Started coding.
18  *	X.25 002	Jonathan Naylor	Centralised disconnect handling.
19  *					New timer architecture.
20  *	2000-03-11	Henner Eisen	MSG_EOR handling more POSIX compliant.
21  *	2000-03-22	Daniela Squassoni Allowed disabling/enabling of
22  *					  facilities negotiation and increased
23  *					  the throughput upper limit.
24  *	2000-08-27	Arnaldo C. Melo s/suser/capable/ + micro cleanups
25  *	2000-09-04	Henner Eisen	Set sock->state in x25_accept().
26  *					Fixed x25_output() related skb leakage.
27  *	2000-10-02	Henner Eisen	Made x25_kick() single threaded per socket.
28  *	2000-10-27	Henner Eisen    MSG_DONTWAIT for fragment allocation.
29  *	2000-11-14	Henner Eisen    Closing datalink from NETDEV_GOING_DOWN
30  *	2002-10-06	Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
31  *					x25_proc.c, using seq_file
32  *	2005-04-02	Shaun Pereira	Selective sub address matching
33  *					with call user data
34  *	2005-04-15	Shaun Pereira	Fast select with no restriction on
35  *					response
36  */
37 
38 #include <linux/module.h>
39 #include <linux/capability.h>
40 #include <linux/errno.h>
41 #include <linux/kernel.h>
42 #include <linux/sched.h>
43 #include <linux/timer.h>
44 #include <linux/string.h>
45 #include <linux/net.h>
46 #include <linux/netdevice.h>
47 #include <linux/if_arp.h>
48 #include <linux/skbuff.h>
49 #include <linux/slab.h>
50 #include <net/sock.h>
51 #include <net/tcp_states.h>
52 #include <asm/uaccess.h>
53 #include <linux/fcntl.h>
54 #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
55 #include <linux/notifier.h>
56 #include <linux/init.h>
57 #include <linux/compat.h>
58 #include <linux/ctype.h>
59 
60 #include <net/x25.h>
61 #include <net/compat.h>
62 
63 int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
64 int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
65 int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
66 int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
67 int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
68 int sysctl_x25_forward                 = 0;
69 
70 HLIST_HEAD(x25_list);
71 DEFINE_RWLOCK(x25_list_lock);
72 
73 static const struct proto_ops x25_proto_ops;
74 
75 static struct x25_address null_x25_address = {"               "};
76 
77 #ifdef CONFIG_COMPAT
78 struct compat_x25_subscrip_struct {
79 	char device[200-sizeof(compat_ulong_t)];
80 	compat_ulong_t global_facil_mask;
81 	compat_uint_t extended;
82 };
83 #endif
84 
85 
86 int x25_parse_address_block(struct sk_buff *skb,
87 		struct x25_address *called_addr,
88 		struct x25_address *calling_addr)
89 {
90 	unsigned char len;
91 	int needed;
92 	int rc;
93 
94 	if (!pskb_may_pull(skb, 1)) {
95 		/* packet has no address block */
96 		rc = 0;
97 		goto empty;
98 	}
99 
100 	len = *skb->data;
101 	needed = 1 + (len >> 4) + (len & 0x0f);
102 
103 	if (!pskb_may_pull(skb, needed)) {
104 		/* packet is too short to hold the addresses it claims
105 		   to hold */
106 		rc = -1;
107 		goto empty;
108 	}
109 
110 	return x25_addr_ntoa(skb->data, called_addr, calling_addr);
111 
112 empty:
113 	*called_addr->x25_addr = 0;
114 	*calling_addr->x25_addr = 0;
115 
116 	return rc;
117 }
118 
119 
120 int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
121 		  struct x25_address *calling_addr)
122 {
123 	unsigned int called_len, calling_len;
124 	char *called, *calling;
125 	unsigned int i;
126 
127 	called_len  = (*p >> 0) & 0x0F;
128 	calling_len = (*p >> 4) & 0x0F;
129 
130 	called  = called_addr->x25_addr;
131 	calling = calling_addr->x25_addr;
132 	p++;
133 
134 	for (i = 0; i < (called_len + calling_len); i++) {
135 		if (i < called_len) {
136 			if (i % 2 != 0) {
137 				*called++ = ((*p >> 0) & 0x0F) + '0';
138 				p++;
139 			} else {
140 				*called++ = ((*p >> 4) & 0x0F) + '0';
141 			}
142 		} else {
143 			if (i % 2 != 0) {
144 				*calling++ = ((*p >> 0) & 0x0F) + '0';
145 				p++;
146 			} else {
147 				*calling++ = ((*p >> 4) & 0x0F) + '0';
148 			}
149 		}
150 	}
151 
152 	*called = *calling = '\0';
153 
154 	return 1 + (called_len + calling_len + 1) / 2;
155 }
156 
157 int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
158 		  struct x25_address *calling_addr)
159 {
160 	unsigned int called_len, calling_len;
161 	char *called, *calling;
162 	int i;
163 
164 	called  = called_addr->x25_addr;
165 	calling = calling_addr->x25_addr;
166 
167 	called_len  = strlen(called);
168 	calling_len = strlen(calling);
169 
170 	*p++ = (calling_len << 4) | (called_len << 0);
171 
172 	for (i = 0; i < (called_len + calling_len); i++) {
173 		if (i < called_len) {
174 			if (i % 2 != 0) {
175 				*p |= (*called++ - '0') << 0;
176 				p++;
177 			} else {
178 				*p = 0x00;
179 				*p |= (*called++ - '0') << 4;
180 			}
181 		} else {
182 			if (i % 2 != 0) {
183 				*p |= (*calling++ - '0') << 0;
184 				p++;
185 			} else {
186 				*p = 0x00;
187 				*p |= (*calling++ - '0') << 4;
188 			}
189 		}
190 	}
191 
192 	return 1 + (called_len + calling_len + 1) / 2;
193 }
194 
195 /*
196  *	Socket removal during an interrupt is now safe.
197  */
198 static void x25_remove_socket(struct sock *sk)
199 {
200 	write_lock_bh(&x25_list_lock);
201 	sk_del_node_init(sk);
202 	write_unlock_bh(&x25_list_lock);
203 }
204 
205 /*
206  *	Kill all bound sockets on a dropped device.
207  */
208 static void x25_kill_by_device(struct net_device *dev)
209 {
210 	struct sock *s;
211 	struct hlist_node *node;
212 
213 	write_lock_bh(&x25_list_lock);
214 
215 	sk_for_each(s, node, &x25_list)
216 		if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
217 			x25_disconnect(s, ENETUNREACH, 0, 0);
218 
219 	write_unlock_bh(&x25_list_lock);
220 }
221 
222 /*
223  *	Handle device status changes.
224  */
225 static int x25_device_event(struct notifier_block *this, unsigned long event,
226 			    void *ptr)
227 {
228 	struct net_device *dev = ptr;
229 	struct x25_neigh *nb;
230 
231 	if (!net_eq(dev_net(dev), &init_net))
232 		return NOTIFY_DONE;
233 
234 	if (dev->type == ARPHRD_X25
235 #if IS_ENABLED(CONFIG_LLC)
236 	 || dev->type == ARPHRD_ETHER
237 #endif
238 	 ) {
239 		switch (event) {
240 		case NETDEV_UP:
241 			x25_link_device_up(dev);
242 			break;
243 		case NETDEV_GOING_DOWN:
244 			nb = x25_get_neigh(dev);
245 			if (nb) {
246 				x25_terminate_link(nb);
247 				x25_neigh_put(nb);
248 			}
249 			break;
250 		case NETDEV_DOWN:
251 			x25_kill_by_device(dev);
252 			x25_route_device_down(dev);
253 			x25_link_device_down(dev);
254 			break;
255 		}
256 	}
257 
258 	return NOTIFY_DONE;
259 }
260 
261 /*
262  *	Add a socket to the bound sockets list.
263  */
264 static void x25_insert_socket(struct sock *sk)
265 {
266 	write_lock_bh(&x25_list_lock);
267 	sk_add_node(sk, &x25_list);
268 	write_unlock_bh(&x25_list_lock);
269 }
270 
271 /*
272  *	Find a socket that wants to accept the Call Request we just
273  *	received. Check the full list for an address/cud match.
274  *	If no cuds match return the next_best thing, an address match.
275  *	Note: if a listening socket has cud set it must only get calls
276  *	with matching cud.
277  */
278 static struct sock *x25_find_listener(struct x25_address *addr,
279 					struct sk_buff *skb)
280 {
281 	struct sock *s;
282 	struct sock *next_best;
283 	struct hlist_node *node;
284 
285 	read_lock_bh(&x25_list_lock);
286 	next_best = NULL;
287 
288 	sk_for_each(s, node, &x25_list)
289 		if ((!strcmp(addr->x25_addr,
290 			x25_sk(s)->source_addr.x25_addr) ||
291 				!strcmp(addr->x25_addr,
292 					null_x25_address.x25_addr)) &&
293 					s->sk_state == TCP_LISTEN) {
294 			/*
295 			 * Found a listening socket, now check the incoming
296 			 * call user data vs this sockets call user data
297 			 */
298 			if (x25_sk(s)->cudmatchlength > 0 &&
299 				skb->len >= x25_sk(s)->cudmatchlength) {
300 				if((memcmp(x25_sk(s)->calluserdata.cuddata,
301 					skb->data,
302 					x25_sk(s)->cudmatchlength)) == 0) {
303 					sock_hold(s);
304 					goto found;
305 				 }
306 			} else
307 				next_best = s;
308 		}
309 	if (next_best) {
310 		s = next_best;
311 		sock_hold(s);
312 		goto found;
313 	}
314 	s = NULL;
315 found:
316 	read_unlock_bh(&x25_list_lock);
317 	return s;
318 }
319 
320 /*
321  *	Find a connected X.25 socket given my LCI and neighbour.
322  */
323 static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
324 {
325 	struct sock *s;
326 	struct hlist_node *node;
327 
328 	sk_for_each(s, node, &x25_list)
329 		if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
330 			sock_hold(s);
331 			goto found;
332 		}
333 	s = NULL;
334 found:
335 	return s;
336 }
337 
338 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
339 {
340 	struct sock *s;
341 
342 	read_lock_bh(&x25_list_lock);
343 	s = __x25_find_socket(lci, nb);
344 	read_unlock_bh(&x25_list_lock);
345 	return s;
346 }
347 
348 /*
349  *	Find a unique LCI for a given device.
350  */
351 static unsigned int x25_new_lci(struct x25_neigh *nb)
352 {
353 	unsigned int lci = 1;
354 	struct sock *sk;
355 
356 	read_lock_bh(&x25_list_lock);
357 
358 	while ((sk = __x25_find_socket(lci, nb)) != NULL) {
359 		sock_put(sk);
360 		if (++lci == 4096) {
361 			lci = 0;
362 			break;
363 		}
364 	}
365 
366 	read_unlock_bh(&x25_list_lock);
367 	return lci;
368 }
369 
370 /*
371  *	Deferred destroy.
372  */
373 static void __x25_destroy_socket(struct sock *);
374 
375 /*
376  *	handler for deferred kills.
377  */
378 static void x25_destroy_timer(unsigned long data)
379 {
380 	x25_destroy_socket_from_timer((struct sock *)data);
381 }
382 
383 /*
384  *	This is called from user mode and the timers. Thus it protects itself
385  *	against interrupt users but doesn't worry about being called during
386  *	work. Once it is removed from the queue no interrupt or bottom half
387  *	will touch it and we are (fairly 8-) ) safe.
388  *	Not static as it's used by the timer
389  */
390 static void __x25_destroy_socket(struct sock *sk)
391 {
392 	struct sk_buff *skb;
393 
394 	x25_stop_heartbeat(sk);
395 	x25_stop_timer(sk);
396 
397 	x25_remove_socket(sk);
398 	x25_clear_queues(sk);		/* Flush the queues */
399 
400 	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
401 		if (skb->sk != sk) {		/* A pending connection */
402 			/*
403 			 * Queue the unaccepted socket for death
404 			 */
405 			skb->sk->sk_state = TCP_LISTEN;
406 			sock_set_flag(skb->sk, SOCK_DEAD);
407 			x25_start_heartbeat(skb->sk);
408 			x25_sk(skb->sk)->state = X25_STATE_0;
409 		}
410 
411 		kfree_skb(skb);
412 	}
413 
414 	if (sk_has_allocations(sk)) {
415 		/* Defer: outstanding buffers */
416 		sk->sk_timer.expires  = jiffies + 10 * HZ;
417 		sk->sk_timer.function = x25_destroy_timer;
418 		sk->sk_timer.data = (unsigned long)sk;
419 		add_timer(&sk->sk_timer);
420 	} else {
421 		/* drop last reference so sock_put will free */
422 		__sock_put(sk);
423 	}
424 }
425 
426 void x25_destroy_socket_from_timer(struct sock *sk)
427 {
428 	sock_hold(sk);
429 	bh_lock_sock(sk);
430 	__x25_destroy_socket(sk);
431 	bh_unlock_sock(sk);
432 	sock_put(sk);
433 }
434 
435 /*
436  *	Handling for system calls applied via the various interfaces to a
437  *	X.25 socket object.
438  */
439 
440 static int x25_setsockopt(struct socket *sock, int level, int optname,
441 			  char __user *optval, unsigned int optlen)
442 {
443 	int opt;
444 	struct sock *sk = sock->sk;
445 	int rc = -ENOPROTOOPT;
446 
447 	if (level != SOL_X25 || optname != X25_QBITINCL)
448 		goto out;
449 
450 	rc = -EINVAL;
451 	if (optlen < sizeof(int))
452 		goto out;
453 
454 	rc = -EFAULT;
455 	if (get_user(opt, (int __user *)optval))
456 		goto out;
457 
458 	if (opt)
459 		set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
460 	else
461 		clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
462 	rc = 0;
463 out:
464 	return rc;
465 }
466 
467 static int x25_getsockopt(struct socket *sock, int level, int optname,
468 			  char __user *optval, int __user *optlen)
469 {
470 	struct sock *sk = sock->sk;
471 	int val, len, rc = -ENOPROTOOPT;
472 
473 	if (level != SOL_X25 || optname != X25_QBITINCL)
474 		goto out;
475 
476 	rc = -EFAULT;
477 	if (get_user(len, optlen))
478 		goto out;
479 
480 	len = min_t(unsigned int, len, sizeof(int));
481 
482 	rc = -EINVAL;
483 	if (len < 0)
484 		goto out;
485 
486 	rc = -EFAULT;
487 	if (put_user(len, optlen))
488 		goto out;
489 
490 	val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
491 	rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
492 out:
493 	return rc;
494 }
495 
496 static int x25_listen(struct socket *sock, int backlog)
497 {
498 	struct sock *sk = sock->sk;
499 	int rc = -EOPNOTSUPP;
500 
501 	lock_sock(sk);
502 	if (sk->sk_state != TCP_LISTEN) {
503 		memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
504 		sk->sk_max_ack_backlog = backlog;
505 		sk->sk_state           = TCP_LISTEN;
506 		rc = 0;
507 	}
508 	release_sock(sk);
509 
510 	return rc;
511 }
512 
513 static struct proto x25_proto = {
514 	.name	  = "X25",
515 	.owner	  = THIS_MODULE,
516 	.obj_size = sizeof(struct x25_sock),
517 };
518 
519 static struct sock *x25_alloc_socket(struct net *net)
520 {
521 	struct x25_sock *x25;
522 	struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto);
523 
524 	if (!sk)
525 		goto out;
526 
527 	sock_init_data(NULL, sk);
528 
529 	x25 = x25_sk(sk);
530 	skb_queue_head_init(&x25->ack_queue);
531 	skb_queue_head_init(&x25->fragment_queue);
532 	skb_queue_head_init(&x25->interrupt_in_queue);
533 	skb_queue_head_init(&x25->interrupt_out_queue);
534 out:
535 	return sk;
536 }
537 
538 static int x25_create(struct net *net, struct socket *sock, int protocol,
539 		      int kern)
540 {
541 	struct sock *sk;
542 	struct x25_sock *x25;
543 	int rc = -EAFNOSUPPORT;
544 
545 	if (!net_eq(net, &init_net))
546 		goto out;
547 
548 	rc = -ESOCKTNOSUPPORT;
549 	if (sock->type != SOCK_SEQPACKET)
550 		goto out;
551 
552 	rc = -EINVAL;
553 	if (protocol)
554 		goto out;
555 
556 	rc = -ENOBUFS;
557 	if ((sk = x25_alloc_socket(net)) == NULL)
558 		goto out;
559 
560 	x25 = x25_sk(sk);
561 
562 	sock_init_data(sock, sk);
563 
564 	x25_init_timers(sk);
565 
566 	sock->ops    = &x25_proto_ops;
567 	sk->sk_protocol = protocol;
568 	sk->sk_backlog_rcv = x25_backlog_rcv;
569 
570 	x25->t21   = sysctl_x25_call_request_timeout;
571 	x25->t22   = sysctl_x25_reset_request_timeout;
572 	x25->t23   = sysctl_x25_clear_request_timeout;
573 	x25->t2    = sysctl_x25_ack_holdback_timeout;
574 	x25->state = X25_STATE_0;
575 	x25->cudmatchlength = 0;
576 	set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);	/* normally no cud  */
577 							/* on call accept   */
578 
579 	x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
580 	x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
581 	x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
582 	x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
583 	x25->facilities.throughput  = 0;	/* by default don't negotiate
584 						   throughput */
585 	x25->facilities.reverse     = X25_DEFAULT_REVERSE;
586 	x25->dte_facilities.calling_len = 0;
587 	x25->dte_facilities.called_len = 0;
588 	memset(x25->dte_facilities.called_ae, '\0',
589 			sizeof(x25->dte_facilities.called_ae));
590 	memset(x25->dte_facilities.calling_ae, '\0',
591 			sizeof(x25->dte_facilities.calling_ae));
592 
593 	rc = 0;
594 out:
595 	return rc;
596 }
597 
598 static struct sock *x25_make_new(struct sock *osk)
599 {
600 	struct sock *sk = NULL;
601 	struct x25_sock *x25, *ox25;
602 
603 	if (osk->sk_type != SOCK_SEQPACKET)
604 		goto out;
605 
606 	if ((sk = x25_alloc_socket(sock_net(osk))) == NULL)
607 		goto out;
608 
609 	x25 = x25_sk(sk);
610 
611 	sk->sk_type        = osk->sk_type;
612 	sk->sk_priority    = osk->sk_priority;
613 	sk->sk_protocol    = osk->sk_protocol;
614 	sk->sk_rcvbuf      = osk->sk_rcvbuf;
615 	sk->sk_sndbuf      = osk->sk_sndbuf;
616 	sk->sk_state       = TCP_ESTABLISHED;
617 	sk->sk_backlog_rcv = osk->sk_backlog_rcv;
618 	sock_copy_flags(sk, osk);
619 
620 	ox25 = x25_sk(osk);
621 	x25->t21        = ox25->t21;
622 	x25->t22        = ox25->t22;
623 	x25->t23        = ox25->t23;
624 	x25->t2         = ox25->t2;
625 	x25->flags	= ox25->flags;
626 	x25->facilities = ox25->facilities;
627 	x25->dte_facilities = ox25->dte_facilities;
628 	x25->cudmatchlength = ox25->cudmatchlength;
629 
630 	clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
631 	x25_init_timers(sk);
632 out:
633 	return sk;
634 }
635 
636 static int x25_release(struct socket *sock)
637 {
638 	struct sock *sk = sock->sk;
639 	struct x25_sock *x25;
640 
641 	if (!sk)
642 		return 0;
643 
644 	x25 = x25_sk(sk);
645 
646 	sock_hold(sk);
647 	lock_sock(sk);
648 	switch (x25->state) {
649 
650 		case X25_STATE_0:
651 		case X25_STATE_2:
652 			x25_disconnect(sk, 0, 0, 0);
653 			__x25_destroy_socket(sk);
654 			goto out;
655 
656 		case X25_STATE_1:
657 		case X25_STATE_3:
658 		case X25_STATE_4:
659 			x25_clear_queues(sk);
660 			x25_write_internal(sk, X25_CLEAR_REQUEST);
661 			x25_start_t23timer(sk);
662 			x25->state = X25_STATE_2;
663 			sk->sk_state	= TCP_CLOSE;
664 			sk->sk_shutdown	|= SEND_SHUTDOWN;
665 			sk->sk_state_change(sk);
666 			sock_set_flag(sk, SOCK_DEAD);
667 			sock_set_flag(sk, SOCK_DESTROY);
668 			break;
669 	}
670 
671 	sock_orphan(sk);
672 out:
673 	release_sock(sk);
674 	sock_put(sk);
675 	return 0;
676 }
677 
678 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
679 {
680 	struct sock *sk = sock->sk;
681 	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
682 	int len, i, rc = 0;
683 
684 	if (!sock_flag(sk, SOCK_ZAPPED) ||
685 	    addr_len != sizeof(struct sockaddr_x25) ||
686 	    addr->sx25_family != AF_X25) {
687 		rc = -EINVAL;
688 		goto out;
689 	}
690 
691 	len = strlen(addr->sx25_addr.x25_addr);
692 	for (i = 0; i < len; i++) {
693 		if (!isdigit(addr->sx25_addr.x25_addr[i])) {
694 			rc = -EINVAL;
695 			goto out;
696 		}
697 	}
698 
699 	lock_sock(sk);
700 	x25_sk(sk)->source_addr = addr->sx25_addr;
701 	x25_insert_socket(sk);
702 	sock_reset_flag(sk, SOCK_ZAPPED);
703 	release_sock(sk);
704 	SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
705 out:
706 	return rc;
707 }
708 
709 static int x25_wait_for_connection_establishment(struct sock *sk)
710 {
711 	DECLARE_WAITQUEUE(wait, current);
712 	int rc;
713 
714 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
715 	for (;;) {
716 		__set_current_state(TASK_INTERRUPTIBLE);
717 		rc = -ERESTARTSYS;
718 		if (signal_pending(current))
719 			break;
720 		rc = sock_error(sk);
721 		if (rc) {
722 			sk->sk_socket->state = SS_UNCONNECTED;
723 			break;
724 		}
725 		rc = 0;
726 		if (sk->sk_state != TCP_ESTABLISHED) {
727 			release_sock(sk);
728 			schedule();
729 			lock_sock(sk);
730 		} else
731 			break;
732 	}
733 	__set_current_state(TASK_RUNNING);
734 	remove_wait_queue(sk_sleep(sk), &wait);
735 	return rc;
736 }
737 
738 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
739 		       int addr_len, int flags)
740 {
741 	struct sock *sk = sock->sk;
742 	struct x25_sock *x25 = x25_sk(sk);
743 	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
744 	struct x25_route *rt;
745 	int rc = 0;
746 
747 	lock_sock(sk);
748 	if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
749 		sock->state = SS_CONNECTED;
750 		goto out; /* Connect completed during a ERESTARTSYS event */
751 	}
752 
753 	rc = -ECONNREFUSED;
754 	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
755 		sock->state = SS_UNCONNECTED;
756 		goto out;
757 	}
758 
759 	rc = -EISCONN;	/* No reconnect on a seqpacket socket */
760 	if (sk->sk_state == TCP_ESTABLISHED)
761 		goto out;
762 
763 	sk->sk_state   = TCP_CLOSE;
764 	sock->state = SS_UNCONNECTED;
765 
766 	rc = -EINVAL;
767 	if (addr_len != sizeof(struct sockaddr_x25) ||
768 	    addr->sx25_family != AF_X25)
769 		goto out;
770 
771 	rc = -ENETUNREACH;
772 	rt = x25_get_route(&addr->sx25_addr);
773 	if (!rt)
774 		goto out;
775 
776 	x25->neighbour = x25_get_neigh(rt->dev);
777 	if (!x25->neighbour)
778 		goto out_put_route;
779 
780 	x25_limit_facilities(&x25->facilities, x25->neighbour);
781 
782 	x25->lci = x25_new_lci(x25->neighbour);
783 	if (!x25->lci)
784 		goto out_put_neigh;
785 
786 	rc = -EINVAL;
787 	if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
788 		goto out_put_neigh;
789 
790 	if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
791 		memset(&x25->source_addr, '\0', X25_ADDR_LEN);
792 
793 	x25->dest_addr = addr->sx25_addr;
794 
795 	/* Move to connecting socket, start sending Connect Requests */
796 	sock->state   = SS_CONNECTING;
797 	sk->sk_state  = TCP_SYN_SENT;
798 
799 	x25->state = X25_STATE_1;
800 
801 	x25_write_internal(sk, X25_CALL_REQUEST);
802 
803 	x25_start_heartbeat(sk);
804 	x25_start_t21timer(sk);
805 
806 	/* Now the loop */
807 	rc = -EINPROGRESS;
808 	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
809 		goto out_put_neigh;
810 
811 	rc = x25_wait_for_connection_establishment(sk);
812 	if (rc)
813 		goto out_put_neigh;
814 
815 	sock->state = SS_CONNECTED;
816 	rc = 0;
817 out_put_neigh:
818 	if (rc)
819 		x25_neigh_put(x25->neighbour);
820 out_put_route:
821 	x25_route_put(rt);
822 out:
823 	release_sock(sk);
824 	return rc;
825 }
826 
827 static int x25_wait_for_data(struct sock *sk, long timeout)
828 {
829 	DECLARE_WAITQUEUE(wait, current);
830 	int rc = 0;
831 
832 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
833 	for (;;) {
834 		__set_current_state(TASK_INTERRUPTIBLE);
835 		if (sk->sk_shutdown & RCV_SHUTDOWN)
836 			break;
837 		rc = -ERESTARTSYS;
838 		if (signal_pending(current))
839 			break;
840 		rc = -EAGAIN;
841 		if (!timeout)
842 			break;
843 		rc = 0;
844 		if (skb_queue_empty(&sk->sk_receive_queue)) {
845 			release_sock(sk);
846 			timeout = schedule_timeout(timeout);
847 			lock_sock(sk);
848 		} else
849 			break;
850 	}
851 	__set_current_state(TASK_RUNNING);
852 	remove_wait_queue(sk_sleep(sk), &wait);
853 	return rc;
854 }
855 
856 static int x25_accept(struct socket *sock, struct socket *newsock, int flags)
857 {
858 	struct sock *sk = sock->sk;
859 	struct sock *newsk;
860 	struct sk_buff *skb;
861 	int rc = -EINVAL;
862 
863 	if (!sk)
864 		goto out;
865 
866 	rc = -EOPNOTSUPP;
867 	if (sk->sk_type != SOCK_SEQPACKET)
868 		goto out;
869 
870 	lock_sock(sk);
871 	rc = -EINVAL;
872 	if (sk->sk_state != TCP_LISTEN)
873 		goto out2;
874 
875 	rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
876 	if (rc)
877 		goto out2;
878 	skb = skb_dequeue(&sk->sk_receive_queue);
879 	rc = -EINVAL;
880 	if (!skb->sk)
881 		goto out2;
882 	newsk		 = skb->sk;
883 	sock_graft(newsk, newsock);
884 
885 	/* Now attach up the new socket */
886 	skb->sk = NULL;
887 	kfree_skb(skb);
888 	sk->sk_ack_backlog--;
889 	newsock->state = SS_CONNECTED;
890 	rc = 0;
891 out2:
892 	release_sock(sk);
893 out:
894 	return rc;
895 }
896 
897 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
898 		       int *uaddr_len, int peer)
899 {
900 	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
901 	struct sock *sk = sock->sk;
902 	struct x25_sock *x25 = x25_sk(sk);
903 	int rc = 0;
904 
905 	if (peer) {
906 		if (sk->sk_state != TCP_ESTABLISHED) {
907 			rc = -ENOTCONN;
908 			goto out;
909 		}
910 		sx25->sx25_addr = x25->dest_addr;
911 	} else
912 		sx25->sx25_addr = x25->source_addr;
913 
914 	sx25->sx25_family = AF_X25;
915 	*uaddr_len = sizeof(*sx25);
916 
917 out:
918 	return rc;
919 }
920 
921 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
922 			unsigned int lci)
923 {
924 	struct sock *sk;
925 	struct sock *make;
926 	struct x25_sock *makex25;
927 	struct x25_address source_addr, dest_addr;
928 	struct x25_facilities facilities;
929 	struct x25_dte_facilities dte_facilities;
930 	int len, addr_len, rc;
931 
932 	/*
933 	 *	Remove the LCI and frame type.
934 	 */
935 	skb_pull(skb, X25_STD_MIN_LEN);
936 
937 	/*
938 	 *	Extract the X.25 addresses and convert them to ASCII strings,
939 	 *	and remove them.
940 	 *
941 	 *	Address block is mandatory in call request packets
942 	 */
943 	addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
944 	if (addr_len <= 0)
945 		goto out_clear_request;
946 	skb_pull(skb, addr_len);
947 
948 	/*
949 	 *	Get the length of the facilities, skip past them for the moment
950 	 *	get the call user data because this is needed to determine
951 	 *	the correct listener
952 	 *
953 	 *	Facilities length is mandatory in call request packets
954 	 */
955 	if (!pskb_may_pull(skb, 1))
956 		goto out_clear_request;
957 	len = skb->data[0] + 1;
958 	if (!pskb_may_pull(skb, len))
959 		goto out_clear_request;
960 	skb_pull(skb,len);
961 
962 	/*
963 	 *	Ensure that the amount of call user data is valid.
964 	 */
965 	if (skb->len > X25_MAX_CUD_LEN)
966 		goto out_clear_request;
967 
968 	/*
969 	 *	Get all the call user data so it can be used in
970 	 *	x25_find_listener and skb_copy_from_linear_data up ahead.
971 	 */
972 	if (!pskb_may_pull(skb, skb->len))
973 		goto out_clear_request;
974 
975 	/*
976 	 *	Find a listener for the particular address/cud pair.
977 	 */
978 	sk = x25_find_listener(&source_addr,skb);
979 	skb_push(skb,len);
980 
981 	if (sk != NULL && sk_acceptq_is_full(sk)) {
982 		goto out_sock_put;
983 	}
984 
985 	/*
986 	 *	We dont have any listeners for this incoming call.
987 	 *	Try forwarding it.
988 	 */
989 	if (sk == NULL) {
990 		skb_push(skb, addr_len + X25_STD_MIN_LEN);
991 		if (sysctl_x25_forward &&
992 				x25_forward_call(&dest_addr, nb, skb, lci) > 0)
993 		{
994 			/* Call was forwarded, dont process it any more */
995 			kfree_skb(skb);
996 			rc = 1;
997 			goto out;
998 		} else {
999 			/* No listeners, can't forward, clear the call */
1000 			goto out_clear_request;
1001 		}
1002 	}
1003 
1004 	/*
1005 	 *	Try to reach a compromise on the requested facilities.
1006 	 */
1007 	len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1008 	if (len == -1)
1009 		goto out_sock_put;
1010 
1011 	/*
1012 	 * current neighbour/link might impose additional limits
1013 	 * on certain facilties
1014 	 */
1015 
1016 	x25_limit_facilities(&facilities, nb);
1017 
1018 	/*
1019 	 *	Try to create a new socket.
1020 	 */
1021 	make = x25_make_new(sk);
1022 	if (!make)
1023 		goto out_sock_put;
1024 
1025 	/*
1026 	 *	Remove the facilities
1027 	 */
1028 	skb_pull(skb, len);
1029 
1030 	skb->sk     = make;
1031 	make->sk_state = TCP_ESTABLISHED;
1032 
1033 	makex25 = x25_sk(make);
1034 	makex25->lci           = lci;
1035 	makex25->dest_addr     = dest_addr;
1036 	makex25->source_addr   = source_addr;
1037 	makex25->neighbour     = nb;
1038 	makex25->facilities    = facilities;
1039 	makex25->dte_facilities= dte_facilities;
1040 	makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1041 	/* ensure no reverse facil on accept */
1042 	makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1043 	/* ensure no calling address extension on accept */
1044 	makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1045 	makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1046 
1047 	/* Normally all calls are accepted immediately */
1048 	if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1049 		x25_write_internal(make, X25_CALL_ACCEPTED);
1050 		makex25->state = X25_STATE_3;
1051 	}
1052 
1053 	/*
1054 	 *	Incoming Call User Data.
1055 	 */
1056 	skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1057 	makex25->calluserdata.cudlength = skb->len;
1058 
1059 	sk->sk_ack_backlog++;
1060 
1061 	x25_insert_socket(make);
1062 
1063 	skb_queue_head(&sk->sk_receive_queue, skb);
1064 
1065 	x25_start_heartbeat(make);
1066 
1067 	if (!sock_flag(sk, SOCK_DEAD))
1068 		sk->sk_data_ready(sk, skb->len);
1069 	rc = 1;
1070 	sock_put(sk);
1071 out:
1072 	return rc;
1073 out_sock_put:
1074 	sock_put(sk);
1075 out_clear_request:
1076 	rc = 0;
1077 	x25_transmit_clear_request(nb, lci, 0x01);
1078 	goto out;
1079 }
1080 
1081 static int x25_sendmsg(struct kiocb *iocb, struct socket *sock,
1082 		       struct msghdr *msg, size_t len)
1083 {
1084 	struct sock *sk = sock->sk;
1085 	struct x25_sock *x25 = x25_sk(sk);
1086 	struct sockaddr_x25 *usx25 = (struct sockaddr_x25 *)msg->msg_name;
1087 	struct sockaddr_x25 sx25;
1088 	struct sk_buff *skb;
1089 	unsigned char *asmptr;
1090 	int noblock = msg->msg_flags & MSG_DONTWAIT;
1091 	size_t size;
1092 	int qbit = 0, rc = -EINVAL;
1093 
1094 	lock_sock(sk);
1095 	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1096 		goto out;
1097 
1098 	/* we currently don't support segmented records at the user interface */
1099 	if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1100 		goto out;
1101 
1102 	rc = -EADDRNOTAVAIL;
1103 	if (sock_flag(sk, SOCK_ZAPPED))
1104 		goto out;
1105 
1106 	rc = -EPIPE;
1107 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1108 		send_sig(SIGPIPE, current, 0);
1109 		goto out;
1110 	}
1111 
1112 	rc = -ENETUNREACH;
1113 	if (!x25->neighbour)
1114 		goto out;
1115 
1116 	if (usx25) {
1117 		rc = -EINVAL;
1118 		if (msg->msg_namelen < sizeof(sx25))
1119 			goto out;
1120 		memcpy(&sx25, usx25, sizeof(sx25));
1121 		rc = -EISCONN;
1122 		if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1123 			goto out;
1124 		rc = -EINVAL;
1125 		if (sx25.sx25_family != AF_X25)
1126 			goto out;
1127 	} else {
1128 		/*
1129 		 *	FIXME 1003.1g - if the socket is like this because
1130 		 *	it has become closed (not started closed) we ought
1131 		 *	to SIGPIPE, EPIPE;
1132 		 */
1133 		rc = -ENOTCONN;
1134 		if (sk->sk_state != TCP_ESTABLISHED)
1135 			goto out;
1136 
1137 		sx25.sx25_family = AF_X25;
1138 		sx25.sx25_addr   = x25->dest_addr;
1139 	}
1140 
1141 	/* Sanity check the packet size */
1142 	if (len > 65535) {
1143 		rc = -EMSGSIZE;
1144 		goto out;
1145 	}
1146 
1147 	SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1148 
1149 	/* Build a packet */
1150 	SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1151 
1152 	if ((msg->msg_flags & MSG_OOB) && len > 32)
1153 		len = 32;
1154 
1155 	size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1156 
1157 	release_sock(sk);
1158 	skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1159 	lock_sock(sk);
1160 	if (!skb)
1161 		goto out;
1162 	X25_SKB_CB(skb)->flags = msg->msg_flags;
1163 
1164 	skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1165 
1166 	/*
1167 	 *	Put the data on the end
1168 	 */
1169 	SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1170 
1171 	skb_reset_transport_header(skb);
1172 	skb_put(skb, len);
1173 
1174 	rc = memcpy_fromiovec(skb_transport_header(skb), msg->msg_iov, len);
1175 	if (rc)
1176 		goto out_kfree_skb;
1177 
1178 	/*
1179 	 *	If the Q BIT Include socket option is in force, the first
1180 	 *	byte of the user data is the logical value of the Q Bit.
1181 	 */
1182 	if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1183 		if (!pskb_may_pull(skb, 1))
1184 			goto out_kfree_skb;
1185 
1186 		qbit = skb->data[0];
1187 		skb_pull(skb, 1);
1188 	}
1189 
1190 	/*
1191 	 *	Push down the X.25 header
1192 	 */
1193 	SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1194 
1195 	if (msg->msg_flags & MSG_OOB) {
1196 		if (x25->neighbour->extended) {
1197 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1198 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1199 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1200 			*asmptr++ = X25_INTERRUPT;
1201 		} else {
1202 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1203 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1204 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1205 			*asmptr++ = X25_INTERRUPT;
1206 		}
1207 	} else {
1208 		if (x25->neighbour->extended) {
1209 			/* Build an Extended X.25 header */
1210 			asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1211 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1212 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1213 			*asmptr++ = X25_DATA;
1214 			*asmptr++ = X25_DATA;
1215 		} else {
1216 			/* Build an Standard X.25 header */
1217 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1218 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1219 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1220 			*asmptr++ = X25_DATA;
1221 		}
1222 
1223 		if (qbit)
1224 			skb->data[0] |= X25_Q_BIT;
1225 	}
1226 
1227 	SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1228 	SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1229 
1230 	rc = -ENOTCONN;
1231 	if (sk->sk_state != TCP_ESTABLISHED)
1232 		goto out_kfree_skb;
1233 
1234 	if (msg->msg_flags & MSG_OOB)
1235 		skb_queue_tail(&x25->interrupt_out_queue, skb);
1236 	else {
1237 		rc = x25_output(sk, skb);
1238 		len = rc;
1239 		if (rc < 0)
1240 			kfree_skb(skb);
1241 		else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1242 			len++;
1243 	}
1244 
1245 	x25_kick(sk);
1246 	rc = len;
1247 out:
1248 	release_sock(sk);
1249 	return rc;
1250 out_kfree_skb:
1251 	kfree_skb(skb);
1252 	goto out;
1253 }
1254 
1255 
1256 static int x25_recvmsg(struct kiocb *iocb, struct socket *sock,
1257 		       struct msghdr *msg, size_t size,
1258 		       int flags)
1259 {
1260 	struct sock *sk = sock->sk;
1261 	struct x25_sock *x25 = x25_sk(sk);
1262 	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)msg->msg_name;
1263 	size_t copied;
1264 	int qbit, header_len;
1265 	struct sk_buff *skb;
1266 	unsigned char *asmptr;
1267 	int rc = -ENOTCONN;
1268 
1269 	lock_sock(sk);
1270 
1271 	if (x25->neighbour == NULL)
1272 		goto out;
1273 
1274 	header_len = x25->neighbour->extended ?
1275 		X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1276 
1277 	/*
1278 	 * This works for seqpacket too. The receiver has ordered the queue for
1279 	 * us! We do one quick check first though
1280 	 */
1281 	if (sk->sk_state != TCP_ESTABLISHED)
1282 		goto out;
1283 
1284 	if (flags & MSG_OOB) {
1285 		rc = -EINVAL;
1286 		if (sock_flag(sk, SOCK_URGINLINE) ||
1287 		    !skb_peek(&x25->interrupt_in_queue))
1288 			goto out;
1289 
1290 		skb = skb_dequeue(&x25->interrupt_in_queue);
1291 
1292 		if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1293 			goto out_free_dgram;
1294 
1295 		skb_pull(skb, X25_STD_MIN_LEN);
1296 
1297 		/*
1298 		 *	No Q bit information on Interrupt data.
1299 		 */
1300 		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1301 			asmptr  = skb_push(skb, 1);
1302 			*asmptr = 0x00;
1303 		}
1304 
1305 		msg->msg_flags |= MSG_OOB;
1306 	} else {
1307 		/* Now we can treat all alike */
1308 		release_sock(sk);
1309 		skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1310 					flags & MSG_DONTWAIT, &rc);
1311 		lock_sock(sk);
1312 		if (!skb)
1313 			goto out;
1314 
1315 		if (!pskb_may_pull(skb, header_len))
1316 			goto out_free_dgram;
1317 
1318 		qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1319 
1320 		skb_pull(skb, header_len);
1321 
1322 		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1323 			asmptr  = skb_push(skb, 1);
1324 			*asmptr = qbit;
1325 		}
1326 	}
1327 
1328 	skb_reset_transport_header(skb);
1329 	copied = skb->len;
1330 
1331 	if (copied > size) {
1332 		copied = size;
1333 		msg->msg_flags |= MSG_TRUNC;
1334 	}
1335 
1336 	/* Currently, each datagram always contains a complete record */
1337 	msg->msg_flags |= MSG_EOR;
1338 
1339 	rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1340 	if (rc)
1341 		goto out_free_dgram;
1342 
1343 	if (sx25) {
1344 		sx25->sx25_family = AF_X25;
1345 		sx25->sx25_addr   = x25->dest_addr;
1346 	}
1347 
1348 	msg->msg_namelen = sizeof(struct sockaddr_x25);
1349 
1350 	x25_check_rbuf(sk);
1351 	rc = copied;
1352 out_free_dgram:
1353 	skb_free_datagram(sk, skb);
1354 out:
1355 	release_sock(sk);
1356 	return rc;
1357 }
1358 
1359 
1360 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1361 {
1362 	struct sock *sk = sock->sk;
1363 	struct x25_sock *x25 = x25_sk(sk);
1364 	void __user *argp = (void __user *)arg;
1365 	int rc;
1366 
1367 	switch (cmd) {
1368 	case TIOCOUTQ: {
1369 		int amount;
1370 
1371 		amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1372 		if (amount < 0)
1373 			amount = 0;
1374 		rc = put_user(amount, (unsigned int __user *)argp);
1375 		break;
1376 	}
1377 
1378 	case TIOCINQ: {
1379 		struct sk_buff *skb;
1380 		int amount = 0;
1381 		/*
1382 		 * These two are safe on a single CPU system as
1383 		 * only user tasks fiddle here
1384 		 */
1385 		lock_sock(sk);
1386 		if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1387 			amount = skb->len;
1388 		release_sock(sk);
1389 		rc = put_user(amount, (unsigned int __user *)argp);
1390 		break;
1391 	}
1392 
1393 	case SIOCGSTAMP:
1394 		rc = -EINVAL;
1395 		if (sk)
1396 			rc = sock_get_timestamp(sk,
1397 						(struct timeval __user *)argp);
1398 		break;
1399 	case SIOCGSTAMPNS:
1400 		rc = -EINVAL;
1401 		if (sk)
1402 			rc = sock_get_timestampns(sk,
1403 					(struct timespec __user *)argp);
1404 		break;
1405 	case SIOCGIFADDR:
1406 	case SIOCSIFADDR:
1407 	case SIOCGIFDSTADDR:
1408 	case SIOCSIFDSTADDR:
1409 	case SIOCGIFBRDADDR:
1410 	case SIOCSIFBRDADDR:
1411 	case SIOCGIFNETMASK:
1412 	case SIOCSIFNETMASK:
1413 	case SIOCGIFMETRIC:
1414 	case SIOCSIFMETRIC:
1415 		rc = -EINVAL;
1416 		break;
1417 	case SIOCADDRT:
1418 	case SIOCDELRT:
1419 		rc = -EPERM;
1420 		if (!capable(CAP_NET_ADMIN))
1421 			break;
1422 		rc = x25_route_ioctl(cmd, argp);
1423 		break;
1424 	case SIOCX25GSUBSCRIP:
1425 		rc = x25_subscr_ioctl(cmd, argp);
1426 		break;
1427 	case SIOCX25SSUBSCRIP:
1428 		rc = -EPERM;
1429 		if (!capable(CAP_NET_ADMIN))
1430 			break;
1431 		rc = x25_subscr_ioctl(cmd, argp);
1432 		break;
1433 	case SIOCX25GFACILITIES: {
1434 		lock_sock(sk);
1435 		rc = copy_to_user(argp, &x25->facilities,
1436 				  sizeof(x25->facilities))
1437 			? -EFAULT : 0;
1438 		release_sock(sk);
1439 		break;
1440 	}
1441 
1442 	case SIOCX25SFACILITIES: {
1443 		struct x25_facilities facilities;
1444 		rc = -EFAULT;
1445 		if (copy_from_user(&facilities, argp, sizeof(facilities)))
1446 			break;
1447 		rc = -EINVAL;
1448 		lock_sock(sk);
1449 		if (sk->sk_state != TCP_LISTEN &&
1450 		    sk->sk_state != TCP_CLOSE)
1451 			goto out_fac_release;
1452 		if (facilities.pacsize_in < X25_PS16 ||
1453 		    facilities.pacsize_in > X25_PS4096)
1454 			goto out_fac_release;
1455 		if (facilities.pacsize_out < X25_PS16 ||
1456 		    facilities.pacsize_out > X25_PS4096)
1457 			goto out_fac_release;
1458 		if (facilities.winsize_in < 1 ||
1459 		    facilities.winsize_in > 127)
1460 			goto out_fac_release;
1461 		if (facilities.throughput) {
1462 			int out = facilities.throughput & 0xf0;
1463 			int in  = facilities.throughput & 0x0f;
1464 			if (!out)
1465 				facilities.throughput |=
1466 					X25_DEFAULT_THROUGHPUT << 4;
1467 			else if (out < 0x30 || out > 0xD0)
1468 				goto out_fac_release;
1469 			if (!in)
1470 				facilities.throughput |=
1471 					X25_DEFAULT_THROUGHPUT;
1472 			else if (in < 0x03 || in > 0x0D)
1473 				goto out_fac_release;
1474 		}
1475 		if (facilities.reverse &&
1476 		    (facilities.reverse & 0x81) != 0x81)
1477 			goto out_fac_release;
1478 		x25->facilities = facilities;
1479 		rc = 0;
1480 out_fac_release:
1481 		release_sock(sk);
1482 		break;
1483 	}
1484 
1485 	case SIOCX25GDTEFACILITIES: {
1486 		lock_sock(sk);
1487 		rc = copy_to_user(argp, &x25->dte_facilities,
1488 				  sizeof(x25->dte_facilities));
1489 		release_sock(sk);
1490 		if (rc)
1491 			rc = -EFAULT;
1492 		break;
1493 	}
1494 
1495 	case SIOCX25SDTEFACILITIES: {
1496 		struct x25_dte_facilities dtefacs;
1497 		rc = -EFAULT;
1498 		if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1499 			break;
1500 		rc = -EINVAL;
1501 		lock_sock(sk);
1502 		if (sk->sk_state != TCP_LISTEN &&
1503 		    sk->sk_state != TCP_CLOSE)
1504 			goto out_dtefac_release;
1505 		if (dtefacs.calling_len > X25_MAX_AE_LEN)
1506 			goto out_dtefac_release;
1507 		if (dtefacs.calling_ae == NULL)
1508 			goto out_dtefac_release;
1509 		if (dtefacs.called_len > X25_MAX_AE_LEN)
1510 			goto out_dtefac_release;
1511 		if (dtefacs.called_ae == NULL)
1512 			goto out_dtefac_release;
1513 		x25->dte_facilities = dtefacs;
1514 		rc = 0;
1515 out_dtefac_release:
1516 		release_sock(sk);
1517 		break;
1518 	}
1519 
1520 	case SIOCX25GCALLUSERDATA: {
1521 		lock_sock(sk);
1522 		rc = copy_to_user(argp, &x25->calluserdata,
1523 				  sizeof(x25->calluserdata))
1524 			? -EFAULT : 0;
1525 		release_sock(sk);
1526 		break;
1527 	}
1528 
1529 	case SIOCX25SCALLUSERDATA: {
1530 		struct x25_calluserdata calluserdata;
1531 
1532 		rc = -EFAULT;
1533 		if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1534 			break;
1535 		rc = -EINVAL;
1536 		if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1537 			break;
1538 		lock_sock(sk);
1539 		x25->calluserdata = calluserdata;
1540 		release_sock(sk);
1541 		rc = 0;
1542 		break;
1543 	}
1544 
1545 	case SIOCX25GCAUSEDIAG: {
1546 		lock_sock(sk);
1547 		rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1548 			? -EFAULT : 0;
1549 		release_sock(sk);
1550 		break;
1551 	}
1552 
1553 	case SIOCX25SCAUSEDIAG: {
1554 		struct x25_causediag causediag;
1555 		rc = -EFAULT;
1556 		if (copy_from_user(&causediag, argp, sizeof(causediag)))
1557 			break;
1558 		lock_sock(sk);
1559 		x25->causediag = causediag;
1560 		release_sock(sk);
1561 		rc = 0;
1562 		break;
1563 
1564 	}
1565 
1566 	case SIOCX25SCUDMATCHLEN: {
1567 		struct x25_subaddr sub_addr;
1568 		rc = -EINVAL;
1569 		lock_sock(sk);
1570 		if(sk->sk_state != TCP_CLOSE)
1571 			goto out_cud_release;
1572 		rc = -EFAULT;
1573 		if (copy_from_user(&sub_addr, argp,
1574 				   sizeof(sub_addr)))
1575 			goto out_cud_release;
1576 		rc = -EINVAL;
1577 		if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1578 			goto out_cud_release;
1579 		x25->cudmatchlength = sub_addr.cudmatchlength;
1580 		rc = 0;
1581 out_cud_release:
1582 		release_sock(sk);
1583 		break;
1584 	}
1585 
1586 	case SIOCX25CALLACCPTAPPRV: {
1587 		rc = -EINVAL;
1588 		lock_sock(sk);
1589 		if (sk->sk_state != TCP_CLOSE)
1590 			break;
1591 		clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1592 		release_sock(sk);
1593 		rc = 0;
1594 		break;
1595 	}
1596 
1597 	case SIOCX25SENDCALLACCPT:  {
1598 		rc = -EINVAL;
1599 		lock_sock(sk);
1600 		if (sk->sk_state != TCP_ESTABLISHED)
1601 			break;
1602 		/* must call accptapprv above */
1603 		if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1604 			break;
1605 		x25_write_internal(sk, X25_CALL_ACCEPTED);
1606 		x25->state = X25_STATE_3;
1607 		release_sock(sk);
1608 		rc = 0;
1609 		break;
1610 	}
1611 
1612 	default:
1613 		rc = -ENOIOCTLCMD;
1614 		break;
1615 	}
1616 
1617 	return rc;
1618 }
1619 
1620 static const struct net_proto_family x25_family_ops = {
1621 	.family =	AF_X25,
1622 	.create =	x25_create,
1623 	.owner	=	THIS_MODULE,
1624 };
1625 
1626 #ifdef CONFIG_COMPAT
1627 static int compat_x25_subscr_ioctl(unsigned int cmd,
1628 		struct compat_x25_subscrip_struct __user *x25_subscr32)
1629 {
1630 	struct compat_x25_subscrip_struct x25_subscr;
1631 	struct x25_neigh *nb;
1632 	struct net_device *dev;
1633 	int rc = -EINVAL;
1634 
1635 	rc = -EFAULT;
1636 	if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1637 		goto out;
1638 
1639 	rc = -EINVAL;
1640 	dev = x25_dev_get(x25_subscr.device);
1641 	if (dev == NULL)
1642 		goto out;
1643 
1644 	nb = x25_get_neigh(dev);
1645 	if (nb == NULL)
1646 		goto out_dev_put;
1647 
1648 	dev_put(dev);
1649 
1650 	if (cmd == SIOCX25GSUBSCRIP) {
1651 		read_lock_bh(&x25_neigh_list_lock);
1652 		x25_subscr.extended = nb->extended;
1653 		x25_subscr.global_facil_mask = nb->global_facil_mask;
1654 		read_unlock_bh(&x25_neigh_list_lock);
1655 		rc = copy_to_user(x25_subscr32, &x25_subscr,
1656 				sizeof(*x25_subscr32)) ? -EFAULT : 0;
1657 	} else {
1658 		rc = -EINVAL;
1659 		if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1660 			rc = 0;
1661 			write_lock_bh(&x25_neigh_list_lock);
1662 			nb->extended = x25_subscr.extended;
1663 			nb->global_facil_mask = x25_subscr.global_facil_mask;
1664 			write_unlock_bh(&x25_neigh_list_lock);
1665 		}
1666 	}
1667 	x25_neigh_put(nb);
1668 out:
1669 	return rc;
1670 out_dev_put:
1671 	dev_put(dev);
1672 	goto out;
1673 }
1674 
1675 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1676 				unsigned long arg)
1677 {
1678 	void __user *argp = compat_ptr(arg);
1679 	struct sock *sk = sock->sk;
1680 
1681 	int rc = -ENOIOCTLCMD;
1682 
1683 	switch(cmd) {
1684 	case TIOCOUTQ:
1685 	case TIOCINQ:
1686 		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1687 		break;
1688 	case SIOCGSTAMP:
1689 		rc = -EINVAL;
1690 		if (sk)
1691 			rc = compat_sock_get_timestamp(sk,
1692 					(struct timeval __user*)argp);
1693 		break;
1694 	case SIOCGSTAMPNS:
1695 		rc = -EINVAL;
1696 		if (sk)
1697 			rc = compat_sock_get_timestampns(sk,
1698 					(struct timespec __user*)argp);
1699 		break;
1700 	case SIOCGIFADDR:
1701 	case SIOCSIFADDR:
1702 	case SIOCGIFDSTADDR:
1703 	case SIOCSIFDSTADDR:
1704 	case SIOCGIFBRDADDR:
1705 	case SIOCSIFBRDADDR:
1706 	case SIOCGIFNETMASK:
1707 	case SIOCSIFNETMASK:
1708 	case SIOCGIFMETRIC:
1709 	case SIOCSIFMETRIC:
1710 		rc = -EINVAL;
1711 		break;
1712 	case SIOCADDRT:
1713 	case SIOCDELRT:
1714 		rc = -EPERM;
1715 		if (!capable(CAP_NET_ADMIN))
1716 			break;
1717 		rc = x25_route_ioctl(cmd, argp);
1718 		break;
1719 	case SIOCX25GSUBSCRIP:
1720 		rc = compat_x25_subscr_ioctl(cmd, argp);
1721 		break;
1722 	case SIOCX25SSUBSCRIP:
1723 		rc = -EPERM;
1724 		if (!capable(CAP_NET_ADMIN))
1725 			break;
1726 		rc = compat_x25_subscr_ioctl(cmd, argp);
1727 		break;
1728 	case SIOCX25GFACILITIES:
1729 	case SIOCX25SFACILITIES:
1730 	case SIOCX25GDTEFACILITIES:
1731 	case SIOCX25SDTEFACILITIES:
1732 	case SIOCX25GCALLUSERDATA:
1733 	case SIOCX25SCALLUSERDATA:
1734 	case SIOCX25GCAUSEDIAG:
1735 	case SIOCX25SCAUSEDIAG:
1736 	case SIOCX25SCUDMATCHLEN:
1737 	case SIOCX25CALLACCPTAPPRV:
1738 	case SIOCX25SENDCALLACCPT:
1739 		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1740 		break;
1741 	default:
1742 		rc = -ENOIOCTLCMD;
1743 		break;
1744 	}
1745 	return rc;
1746 }
1747 #endif
1748 
1749 static const struct proto_ops x25_proto_ops = {
1750 	.family =	AF_X25,
1751 	.owner =	THIS_MODULE,
1752 	.release =	x25_release,
1753 	.bind =		x25_bind,
1754 	.connect =	x25_connect,
1755 	.socketpair =	sock_no_socketpair,
1756 	.accept =	x25_accept,
1757 	.getname =	x25_getname,
1758 	.poll =		datagram_poll,
1759 	.ioctl =	x25_ioctl,
1760 #ifdef CONFIG_COMPAT
1761 	.compat_ioctl = compat_x25_ioctl,
1762 #endif
1763 	.listen =	x25_listen,
1764 	.shutdown =	sock_no_shutdown,
1765 	.setsockopt =	x25_setsockopt,
1766 	.getsockopt =	x25_getsockopt,
1767 	.sendmsg =	x25_sendmsg,
1768 	.recvmsg =	x25_recvmsg,
1769 	.mmap =		sock_no_mmap,
1770 	.sendpage =	sock_no_sendpage,
1771 };
1772 
1773 static struct packet_type x25_packet_type __read_mostly = {
1774 	.type =	cpu_to_be16(ETH_P_X25),
1775 	.func =	x25_lapb_receive_frame,
1776 };
1777 
1778 static struct notifier_block x25_dev_notifier = {
1779 	.notifier_call = x25_device_event,
1780 };
1781 
1782 void x25_kill_by_neigh(struct x25_neigh *nb)
1783 {
1784 	struct sock *s;
1785 	struct hlist_node *node;
1786 
1787 	write_lock_bh(&x25_list_lock);
1788 
1789 	sk_for_each(s, node, &x25_list)
1790 		if (x25_sk(s)->neighbour == nb)
1791 			x25_disconnect(s, ENETUNREACH, 0, 0);
1792 
1793 	write_unlock_bh(&x25_list_lock);
1794 
1795 	/* Remove any related forwards */
1796 	x25_clear_forward_by_dev(nb->dev);
1797 }
1798 
1799 static int __init x25_init(void)
1800 {
1801 	int rc = proto_register(&x25_proto, 0);
1802 
1803 	if (rc != 0)
1804 		goto out;
1805 
1806 	rc = sock_register(&x25_family_ops);
1807 	if (rc != 0)
1808 		goto out_proto;
1809 
1810 	dev_add_pack(&x25_packet_type);
1811 
1812 	rc = register_netdevice_notifier(&x25_dev_notifier);
1813 	if (rc != 0)
1814 		goto out_sock;
1815 
1816 	printk(KERN_INFO "X.25 for Linux Version 0.2\n");
1817 
1818 	x25_register_sysctl();
1819 	rc = x25_proc_init();
1820 	if (rc != 0)
1821 		goto out_dev;
1822 out:
1823 	return rc;
1824 out_dev:
1825 	unregister_netdevice_notifier(&x25_dev_notifier);
1826 out_sock:
1827 	sock_unregister(AF_X25);
1828 out_proto:
1829 	proto_unregister(&x25_proto);
1830 	goto out;
1831 }
1832 module_init(x25_init);
1833 
1834 static void __exit x25_exit(void)
1835 {
1836 	x25_proc_exit();
1837 	x25_link_free();
1838 	x25_route_free();
1839 
1840 	x25_unregister_sysctl();
1841 
1842 	unregister_netdevice_notifier(&x25_dev_notifier);
1843 
1844 	dev_remove_pack(&x25_packet_type);
1845 
1846 	sock_unregister(AF_X25);
1847 	proto_unregister(&x25_proto);
1848 }
1849 module_exit(x25_exit);
1850 
1851 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1852 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1853 MODULE_LICENSE("GPL");
1854 MODULE_ALIAS_NETPROTO(PF_X25);
1855