xref: /openbmc/linux/net/x25/af_x25.c (revision 0bea2a65)
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 #define pr_fmt(fmt) "X25: " fmt
39 
40 #include <linux/module.h>
41 #include <linux/capability.h>
42 #include <linux/errno.h>
43 #include <linux/kernel.h>
44 #include <linux/sched/signal.h>
45 #include <linux/timer.h>
46 #include <linux/string.h>
47 #include <linux/net.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_arp.h>
50 #include <linux/skbuff.h>
51 #include <linux/slab.h>
52 #include <net/sock.h>
53 #include <net/tcp_states.h>
54 #include <linux/uaccess.h>
55 #include <linux/fcntl.h>
56 #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
57 #include <linux/notifier.h>
58 #include <linux/init.h>
59 #include <linux/compat.h>
60 #include <linux/ctype.h>
61 
62 #include <net/x25.h>
63 #include <net/compat.h>
64 
65 int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
66 int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
67 int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
68 int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
69 int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
70 int sysctl_x25_forward                 = 0;
71 
72 HLIST_HEAD(x25_list);
73 DEFINE_RWLOCK(x25_list_lock);
74 
75 static const struct proto_ops x25_proto_ops;
76 
77 static const struct x25_address null_x25_address = {"               "};
78 
79 #ifdef CONFIG_COMPAT
80 struct compat_x25_subscrip_struct {
81 	char device[200-sizeof(compat_ulong_t)];
82 	compat_ulong_t global_facil_mask;
83 	compat_uint_t extended;
84 };
85 #endif
86 
87 
88 int x25_parse_address_block(struct sk_buff *skb,
89 		struct x25_address *called_addr,
90 		struct x25_address *calling_addr)
91 {
92 	unsigned char len;
93 	int needed;
94 	int rc;
95 
96 	if (!pskb_may_pull(skb, 1)) {
97 		/* packet has no address block */
98 		rc = 0;
99 		goto empty;
100 	}
101 
102 	len = *skb->data;
103 	needed = 1 + (len >> 4) + (len & 0x0f);
104 
105 	if (!pskb_may_pull(skb, needed)) {
106 		/* packet is too short to hold the addresses it claims
107 		   to hold */
108 		rc = -1;
109 		goto empty;
110 	}
111 
112 	return x25_addr_ntoa(skb->data, called_addr, calling_addr);
113 
114 empty:
115 	*called_addr->x25_addr = 0;
116 	*calling_addr->x25_addr = 0;
117 
118 	return rc;
119 }
120 
121 
122 int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
123 		  struct x25_address *calling_addr)
124 {
125 	unsigned int called_len, calling_len;
126 	char *called, *calling;
127 	unsigned int i;
128 
129 	called_len  = (*p >> 0) & 0x0F;
130 	calling_len = (*p >> 4) & 0x0F;
131 
132 	called  = called_addr->x25_addr;
133 	calling = calling_addr->x25_addr;
134 	p++;
135 
136 	for (i = 0; i < (called_len + calling_len); i++) {
137 		if (i < called_len) {
138 			if (i % 2 != 0) {
139 				*called++ = ((*p >> 0) & 0x0F) + '0';
140 				p++;
141 			} else {
142 				*called++ = ((*p >> 4) & 0x0F) + '0';
143 			}
144 		} else {
145 			if (i % 2 != 0) {
146 				*calling++ = ((*p >> 0) & 0x0F) + '0';
147 				p++;
148 			} else {
149 				*calling++ = ((*p >> 4) & 0x0F) + '0';
150 			}
151 		}
152 	}
153 
154 	*called = *calling = '\0';
155 
156 	return 1 + (called_len + calling_len + 1) / 2;
157 }
158 
159 int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
160 		  struct x25_address *calling_addr)
161 {
162 	unsigned int called_len, calling_len;
163 	char *called, *calling;
164 	int i;
165 
166 	called  = called_addr->x25_addr;
167 	calling = calling_addr->x25_addr;
168 
169 	called_len  = strlen(called);
170 	calling_len = strlen(calling);
171 
172 	*p++ = (calling_len << 4) | (called_len << 0);
173 
174 	for (i = 0; i < (called_len + calling_len); i++) {
175 		if (i < called_len) {
176 			if (i % 2 != 0) {
177 				*p |= (*called++ - '0') << 0;
178 				p++;
179 			} else {
180 				*p = 0x00;
181 				*p |= (*called++ - '0') << 4;
182 			}
183 		} else {
184 			if (i % 2 != 0) {
185 				*p |= (*calling++ - '0') << 0;
186 				p++;
187 			} else {
188 				*p = 0x00;
189 				*p |= (*calling++ - '0') << 4;
190 			}
191 		}
192 	}
193 
194 	return 1 + (called_len + calling_len + 1) / 2;
195 }
196 
197 /*
198  *	Socket removal during an interrupt is now safe.
199  */
200 static void x25_remove_socket(struct sock *sk)
201 {
202 	write_lock_bh(&x25_list_lock);
203 	sk_del_node_init(sk);
204 	write_unlock_bh(&x25_list_lock);
205 }
206 
207 /*
208  *	Kill all bound sockets on a dropped device.
209  */
210 static void x25_kill_by_device(struct net_device *dev)
211 {
212 	struct sock *s;
213 
214 	write_lock_bh(&x25_list_lock);
215 
216 	sk_for_each(s, &x25_list)
217 		if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
218 			x25_disconnect(s, ENETUNREACH, 0, 0);
219 
220 	write_unlock_bh(&x25_list_lock);
221 }
222 
223 /*
224  *	Handle device status changes.
225  */
226 static int x25_device_event(struct notifier_block *this, unsigned long event,
227 			    void *ptr)
228 {
229 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
230 	struct x25_neigh *nb;
231 
232 	if (!net_eq(dev_net(dev), &init_net))
233 		return NOTIFY_DONE;
234 
235 	if (dev->type == ARPHRD_X25
236 #if IS_ENABLED(CONFIG_LLC)
237 	 || dev->type == ARPHRD_ETHER
238 #endif
239 	 ) {
240 		switch (event) {
241 		case NETDEV_UP:
242 			x25_link_device_up(dev);
243 			break;
244 		case NETDEV_GOING_DOWN:
245 			nb = x25_get_neigh(dev);
246 			if (nb) {
247 				x25_terminate_link(nb);
248 				x25_neigh_put(nb);
249 			}
250 			break;
251 		case NETDEV_DOWN:
252 			x25_kill_by_device(dev);
253 			x25_route_device_down(dev);
254 			x25_link_device_down(dev);
255 			break;
256 		}
257 	}
258 
259 	return NOTIFY_DONE;
260 }
261 
262 /*
263  *	Add a socket to the bound sockets list.
264  */
265 static void x25_insert_socket(struct sock *sk)
266 {
267 	write_lock_bh(&x25_list_lock);
268 	sk_add_node(sk, &x25_list);
269 	write_unlock_bh(&x25_list_lock);
270 }
271 
272 /*
273  *	Find a socket that wants to accept the Call Request we just
274  *	received. Check the full list for an address/cud match.
275  *	If no cuds match return the next_best thing, an address match.
276  *	Note: if a listening socket has cud set it must only get calls
277  *	with matching cud.
278  */
279 static struct sock *x25_find_listener(struct x25_address *addr,
280 					struct sk_buff *skb)
281 {
282 	struct sock *s;
283 	struct sock *next_best;
284 
285 	read_lock_bh(&x25_list_lock);
286 	next_best = NULL;
287 
288 	sk_for_each(s, &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 
327 	sk_for_each(s, &x25_list)
328 		if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
329 			sock_hold(s);
330 			goto found;
331 		}
332 	s = NULL;
333 found:
334 	return s;
335 }
336 
337 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
338 {
339 	struct sock *s;
340 
341 	read_lock_bh(&x25_list_lock);
342 	s = __x25_find_socket(lci, nb);
343 	read_unlock_bh(&x25_list_lock);
344 	return s;
345 }
346 
347 /*
348  *	Find a unique LCI for a given device.
349  */
350 static unsigned int x25_new_lci(struct x25_neigh *nb)
351 {
352 	unsigned int lci = 1;
353 	struct sock *sk;
354 
355 	read_lock_bh(&x25_list_lock);
356 
357 	while ((sk = __x25_find_socket(lci, nb)) != NULL) {
358 		sock_put(sk);
359 		if (++lci == 4096) {
360 			lci = 0;
361 			break;
362 		}
363 	}
364 
365 	read_unlock_bh(&x25_list_lock);
366 	return lci;
367 }
368 
369 /*
370  *	Deferred destroy.
371  */
372 static void __x25_destroy_socket(struct sock *);
373 
374 /*
375  *	handler for deferred kills.
376  */
377 static void x25_destroy_timer(struct timer_list *t)
378 {
379 	struct sock *sk = from_timer(sk, t, sk_timer);
380 
381 	x25_destroy_socket_from_timer(sk);
382 }
383 
384 /*
385  *	This is called from user mode and the timers. Thus it protects itself
386  *	against interrupt users but doesn't worry about being called during
387  *	work. Once it is removed from the queue no interrupt or bottom half
388  *	will touch it and we are (fairly 8-) ) safe.
389  *	Not static as it's used by the timer
390  */
391 static void __x25_destroy_socket(struct sock *sk)
392 {
393 	struct sk_buff *skb;
394 
395 	x25_stop_heartbeat(sk);
396 	x25_stop_timer(sk);
397 
398 	x25_remove_socket(sk);
399 	x25_clear_queues(sk);		/* Flush the queues */
400 
401 	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
402 		if (skb->sk != sk) {		/* A pending connection */
403 			/*
404 			 * Queue the unaccepted socket for death
405 			 */
406 			skb->sk->sk_state = TCP_LISTEN;
407 			sock_set_flag(skb->sk, SOCK_DEAD);
408 			x25_start_heartbeat(skb->sk);
409 			x25_sk(skb->sk)->state = X25_STATE_0;
410 		}
411 
412 		kfree_skb(skb);
413 	}
414 
415 	if (sk_has_allocations(sk)) {
416 		/* Defer: outstanding buffers */
417 		sk->sk_timer.expires  = jiffies + 10 * HZ;
418 		sk->sk_timer.function = x25_destroy_timer;
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, int kern)
520 {
521 	struct x25_sock *x25;
522 	struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
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, kern)) == 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), 0)) == 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 		      bool kern)
858 {
859 	struct sock *sk = sock->sk;
860 	struct sock *newsk;
861 	struct sk_buff *skb;
862 	int rc = -EINVAL;
863 
864 	if (!sk)
865 		goto out;
866 
867 	rc = -EOPNOTSUPP;
868 	if (sk->sk_type != SOCK_SEQPACKET)
869 		goto out;
870 
871 	lock_sock(sk);
872 	rc = -EINVAL;
873 	if (sk->sk_state != TCP_LISTEN)
874 		goto out2;
875 
876 	rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
877 	if (rc)
878 		goto out2;
879 	skb = skb_dequeue(&sk->sk_receive_queue);
880 	rc = -EINVAL;
881 	if (!skb->sk)
882 		goto out2;
883 	newsk		 = skb->sk;
884 	sock_graft(newsk, newsock);
885 
886 	/* Now attach up the new socket */
887 	skb->sk = NULL;
888 	kfree_skb(skb);
889 	sk->sk_ack_backlog--;
890 	newsock->state = SS_CONNECTED;
891 	rc = 0;
892 out2:
893 	release_sock(sk);
894 out:
895 	return rc;
896 }
897 
898 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
899 		       int *uaddr_len, int peer)
900 {
901 	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
902 	struct sock *sk = sock->sk;
903 	struct x25_sock *x25 = x25_sk(sk);
904 	int rc = 0;
905 
906 	if (peer) {
907 		if (sk->sk_state != TCP_ESTABLISHED) {
908 			rc = -ENOTCONN;
909 			goto out;
910 		}
911 		sx25->sx25_addr = x25->dest_addr;
912 	} else
913 		sx25->sx25_addr = x25->source_addr;
914 
915 	sx25->sx25_family = AF_X25;
916 	*uaddr_len = sizeof(*sx25);
917 
918 out:
919 	return rc;
920 }
921 
922 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
923 			unsigned int lci)
924 {
925 	struct sock *sk;
926 	struct sock *make;
927 	struct x25_sock *makex25;
928 	struct x25_address source_addr, dest_addr;
929 	struct x25_facilities facilities;
930 	struct x25_dte_facilities dte_facilities;
931 	int len, addr_len, rc;
932 
933 	/*
934 	 *	Remove the LCI and frame type.
935 	 */
936 	skb_pull(skb, X25_STD_MIN_LEN);
937 
938 	/*
939 	 *	Extract the X.25 addresses and convert them to ASCII strings,
940 	 *	and remove them.
941 	 *
942 	 *	Address block is mandatory in call request packets
943 	 */
944 	addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
945 	if (addr_len <= 0)
946 		goto out_clear_request;
947 	skb_pull(skb, addr_len);
948 
949 	/*
950 	 *	Get the length of the facilities, skip past them for the moment
951 	 *	get the call user data because this is needed to determine
952 	 *	the correct listener
953 	 *
954 	 *	Facilities length is mandatory in call request packets
955 	 */
956 	if (!pskb_may_pull(skb, 1))
957 		goto out_clear_request;
958 	len = skb->data[0] + 1;
959 	if (!pskb_may_pull(skb, len))
960 		goto out_clear_request;
961 	skb_pull(skb,len);
962 
963 	/*
964 	 *	Ensure that the amount of call user data is valid.
965 	 */
966 	if (skb->len > X25_MAX_CUD_LEN)
967 		goto out_clear_request;
968 
969 	/*
970 	 *	Get all the call user data so it can be used in
971 	 *	x25_find_listener and skb_copy_from_linear_data up ahead.
972 	 */
973 	if (!pskb_may_pull(skb, skb->len))
974 		goto out_clear_request;
975 
976 	/*
977 	 *	Find a listener for the particular address/cud pair.
978 	 */
979 	sk = x25_find_listener(&source_addr,skb);
980 	skb_push(skb,len);
981 
982 	if (sk != NULL && sk_acceptq_is_full(sk)) {
983 		goto out_sock_put;
984 	}
985 
986 	/*
987 	 *	We dont have any listeners for this incoming call.
988 	 *	Try forwarding it.
989 	 */
990 	if (sk == NULL) {
991 		skb_push(skb, addr_len + X25_STD_MIN_LEN);
992 		if (sysctl_x25_forward &&
993 				x25_forward_call(&dest_addr, nb, skb, lci) > 0)
994 		{
995 			/* Call was forwarded, dont process it any more */
996 			kfree_skb(skb);
997 			rc = 1;
998 			goto out;
999 		} else {
1000 			/* No listeners, can't forward, clear the call */
1001 			goto out_clear_request;
1002 		}
1003 	}
1004 
1005 	/*
1006 	 *	Try to reach a compromise on the requested facilities.
1007 	 */
1008 	len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1009 	if (len == -1)
1010 		goto out_sock_put;
1011 
1012 	/*
1013 	 * current neighbour/link might impose additional limits
1014 	 * on certain facilties
1015 	 */
1016 
1017 	x25_limit_facilities(&facilities, nb);
1018 
1019 	/*
1020 	 *	Try to create a new socket.
1021 	 */
1022 	make = x25_make_new(sk);
1023 	if (!make)
1024 		goto out_sock_put;
1025 
1026 	/*
1027 	 *	Remove the facilities
1028 	 */
1029 	skb_pull(skb, len);
1030 
1031 	skb->sk     = make;
1032 	make->sk_state = TCP_ESTABLISHED;
1033 
1034 	makex25 = x25_sk(make);
1035 	makex25->lci           = lci;
1036 	makex25->dest_addr     = dest_addr;
1037 	makex25->source_addr   = source_addr;
1038 	makex25->neighbour     = nb;
1039 	makex25->facilities    = facilities;
1040 	makex25->dte_facilities= dte_facilities;
1041 	makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1042 	/* ensure no reverse facil on accept */
1043 	makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1044 	/* ensure no calling address extension on accept */
1045 	makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1046 	makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1047 
1048 	/* Normally all calls are accepted immediately */
1049 	if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1050 		x25_write_internal(make, X25_CALL_ACCEPTED);
1051 		makex25->state = X25_STATE_3;
1052 	}
1053 
1054 	/*
1055 	 *	Incoming Call User Data.
1056 	 */
1057 	skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1058 	makex25->calluserdata.cudlength = skb->len;
1059 
1060 	sk->sk_ack_backlog++;
1061 
1062 	x25_insert_socket(make);
1063 
1064 	skb_queue_head(&sk->sk_receive_queue, skb);
1065 
1066 	x25_start_heartbeat(make);
1067 
1068 	if (!sock_flag(sk, SOCK_DEAD))
1069 		sk->sk_data_ready(sk);
1070 	rc = 1;
1071 	sock_put(sk);
1072 out:
1073 	return rc;
1074 out_sock_put:
1075 	sock_put(sk);
1076 out_clear_request:
1077 	rc = 0;
1078 	x25_transmit_clear_request(nb, lci, 0x01);
1079 	goto out;
1080 }
1081 
1082 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1083 {
1084 	struct sock *sk = sock->sk;
1085 	struct x25_sock *x25 = x25_sk(sk);
1086 	DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, 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_from_msg(skb_transport_header(skb), msg, 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 socket *sock, struct msghdr *msg, size_t size,
1257 		       int flags)
1258 {
1259 	struct sock *sk = sock->sk;
1260 	struct x25_sock *x25 = x25_sk(sk);
1261 	DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1262 	size_t copied;
1263 	int qbit, header_len;
1264 	struct sk_buff *skb;
1265 	unsigned char *asmptr;
1266 	int rc = -ENOTCONN;
1267 
1268 	lock_sock(sk);
1269 
1270 	if (x25->neighbour == NULL)
1271 		goto out;
1272 
1273 	header_len = x25->neighbour->extended ?
1274 		X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1275 
1276 	/*
1277 	 * This works for seqpacket too. The receiver has ordered the queue for
1278 	 * us! We do one quick check first though
1279 	 */
1280 	if (sk->sk_state != TCP_ESTABLISHED)
1281 		goto out;
1282 
1283 	if (flags & MSG_OOB) {
1284 		rc = -EINVAL;
1285 		if (sock_flag(sk, SOCK_URGINLINE) ||
1286 		    !skb_peek(&x25->interrupt_in_queue))
1287 			goto out;
1288 
1289 		skb = skb_dequeue(&x25->interrupt_in_queue);
1290 
1291 		if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1292 			goto out_free_dgram;
1293 
1294 		skb_pull(skb, X25_STD_MIN_LEN);
1295 
1296 		/*
1297 		 *	No Q bit information on Interrupt data.
1298 		 */
1299 		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1300 			asmptr  = skb_push(skb, 1);
1301 			*asmptr = 0x00;
1302 		}
1303 
1304 		msg->msg_flags |= MSG_OOB;
1305 	} else {
1306 		/* Now we can treat all alike */
1307 		release_sock(sk);
1308 		skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1309 					flags & MSG_DONTWAIT, &rc);
1310 		lock_sock(sk);
1311 		if (!skb)
1312 			goto out;
1313 
1314 		if (!pskb_may_pull(skb, header_len))
1315 			goto out_free_dgram;
1316 
1317 		qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1318 
1319 		skb_pull(skb, header_len);
1320 
1321 		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1322 			asmptr  = skb_push(skb, 1);
1323 			*asmptr = qbit;
1324 		}
1325 	}
1326 
1327 	skb_reset_transport_header(skb);
1328 	copied = skb->len;
1329 
1330 	if (copied > size) {
1331 		copied = size;
1332 		msg->msg_flags |= MSG_TRUNC;
1333 	}
1334 
1335 	/* Currently, each datagram always contains a complete record */
1336 	msg->msg_flags |= MSG_EOR;
1337 
1338 	rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1339 	if (rc)
1340 		goto out_free_dgram;
1341 
1342 	if (sx25) {
1343 		sx25->sx25_family = AF_X25;
1344 		sx25->sx25_addr   = x25->dest_addr;
1345 		msg->msg_namelen = sizeof(*sx25);
1346 	}
1347 
1348 	x25_check_rbuf(sk);
1349 	rc = copied;
1350 out_free_dgram:
1351 	skb_free_datagram(sk, skb);
1352 out:
1353 	release_sock(sk);
1354 	return rc;
1355 }
1356 
1357 
1358 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1359 {
1360 	struct sock *sk = sock->sk;
1361 	struct x25_sock *x25 = x25_sk(sk);
1362 	void __user *argp = (void __user *)arg;
1363 	int rc;
1364 
1365 	switch (cmd) {
1366 	case TIOCOUTQ: {
1367 		int amount;
1368 
1369 		amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1370 		if (amount < 0)
1371 			amount = 0;
1372 		rc = put_user(amount, (unsigned int __user *)argp);
1373 		break;
1374 	}
1375 
1376 	case TIOCINQ: {
1377 		struct sk_buff *skb;
1378 		int amount = 0;
1379 		/*
1380 		 * These two are safe on a single CPU system as
1381 		 * only user tasks fiddle here
1382 		 */
1383 		lock_sock(sk);
1384 		if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1385 			amount = skb->len;
1386 		release_sock(sk);
1387 		rc = put_user(amount, (unsigned int __user *)argp);
1388 		break;
1389 	}
1390 
1391 	case SIOCGSTAMP:
1392 		rc = -EINVAL;
1393 		if (sk)
1394 			rc = sock_get_timestamp(sk,
1395 						(struct timeval __user *)argp);
1396 		break;
1397 	case SIOCGSTAMPNS:
1398 		rc = -EINVAL;
1399 		if (sk)
1400 			rc = sock_get_timestampns(sk,
1401 					(struct timespec __user *)argp);
1402 		break;
1403 	case SIOCGIFADDR:
1404 	case SIOCSIFADDR:
1405 	case SIOCGIFDSTADDR:
1406 	case SIOCSIFDSTADDR:
1407 	case SIOCGIFBRDADDR:
1408 	case SIOCSIFBRDADDR:
1409 	case SIOCGIFNETMASK:
1410 	case SIOCSIFNETMASK:
1411 	case SIOCGIFMETRIC:
1412 	case SIOCSIFMETRIC:
1413 		rc = -EINVAL;
1414 		break;
1415 	case SIOCADDRT:
1416 	case SIOCDELRT:
1417 		rc = -EPERM;
1418 		if (!capable(CAP_NET_ADMIN))
1419 			break;
1420 		rc = x25_route_ioctl(cmd, argp);
1421 		break;
1422 	case SIOCX25GSUBSCRIP:
1423 		rc = x25_subscr_ioctl(cmd, argp);
1424 		break;
1425 	case SIOCX25SSUBSCRIP:
1426 		rc = -EPERM;
1427 		if (!capable(CAP_NET_ADMIN))
1428 			break;
1429 		rc = x25_subscr_ioctl(cmd, argp);
1430 		break;
1431 	case SIOCX25GFACILITIES: {
1432 		lock_sock(sk);
1433 		rc = copy_to_user(argp, &x25->facilities,
1434 				  sizeof(x25->facilities))
1435 			? -EFAULT : 0;
1436 		release_sock(sk);
1437 		break;
1438 	}
1439 
1440 	case SIOCX25SFACILITIES: {
1441 		struct x25_facilities facilities;
1442 		rc = -EFAULT;
1443 		if (copy_from_user(&facilities, argp, sizeof(facilities)))
1444 			break;
1445 		rc = -EINVAL;
1446 		lock_sock(sk);
1447 		if (sk->sk_state != TCP_LISTEN &&
1448 		    sk->sk_state != TCP_CLOSE)
1449 			goto out_fac_release;
1450 		if (facilities.pacsize_in < X25_PS16 ||
1451 		    facilities.pacsize_in > X25_PS4096)
1452 			goto out_fac_release;
1453 		if (facilities.pacsize_out < X25_PS16 ||
1454 		    facilities.pacsize_out > X25_PS4096)
1455 			goto out_fac_release;
1456 		if (facilities.winsize_in < 1 ||
1457 		    facilities.winsize_in > 127)
1458 			goto out_fac_release;
1459 		if (facilities.throughput) {
1460 			int out = facilities.throughput & 0xf0;
1461 			int in  = facilities.throughput & 0x0f;
1462 			if (!out)
1463 				facilities.throughput |=
1464 					X25_DEFAULT_THROUGHPUT << 4;
1465 			else if (out < 0x30 || out > 0xD0)
1466 				goto out_fac_release;
1467 			if (!in)
1468 				facilities.throughput |=
1469 					X25_DEFAULT_THROUGHPUT;
1470 			else if (in < 0x03 || in > 0x0D)
1471 				goto out_fac_release;
1472 		}
1473 		if (facilities.reverse &&
1474 		    (facilities.reverse & 0x81) != 0x81)
1475 			goto out_fac_release;
1476 		x25->facilities = facilities;
1477 		rc = 0;
1478 out_fac_release:
1479 		release_sock(sk);
1480 		break;
1481 	}
1482 
1483 	case SIOCX25GDTEFACILITIES: {
1484 		lock_sock(sk);
1485 		rc = copy_to_user(argp, &x25->dte_facilities,
1486 				  sizeof(x25->dte_facilities));
1487 		release_sock(sk);
1488 		if (rc)
1489 			rc = -EFAULT;
1490 		break;
1491 	}
1492 
1493 	case SIOCX25SDTEFACILITIES: {
1494 		struct x25_dte_facilities dtefacs;
1495 		rc = -EFAULT;
1496 		if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1497 			break;
1498 		rc = -EINVAL;
1499 		lock_sock(sk);
1500 		if (sk->sk_state != TCP_LISTEN &&
1501 		    sk->sk_state != TCP_CLOSE)
1502 			goto out_dtefac_release;
1503 		if (dtefacs.calling_len > X25_MAX_AE_LEN)
1504 			goto out_dtefac_release;
1505 		if (dtefacs.called_len > X25_MAX_AE_LEN)
1506 			goto out_dtefac_release;
1507 		x25->dte_facilities = dtefacs;
1508 		rc = 0;
1509 out_dtefac_release:
1510 		release_sock(sk);
1511 		break;
1512 	}
1513 
1514 	case SIOCX25GCALLUSERDATA: {
1515 		lock_sock(sk);
1516 		rc = copy_to_user(argp, &x25->calluserdata,
1517 				  sizeof(x25->calluserdata))
1518 			? -EFAULT : 0;
1519 		release_sock(sk);
1520 		break;
1521 	}
1522 
1523 	case SIOCX25SCALLUSERDATA: {
1524 		struct x25_calluserdata calluserdata;
1525 
1526 		rc = -EFAULT;
1527 		if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1528 			break;
1529 		rc = -EINVAL;
1530 		if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1531 			break;
1532 		lock_sock(sk);
1533 		x25->calluserdata = calluserdata;
1534 		release_sock(sk);
1535 		rc = 0;
1536 		break;
1537 	}
1538 
1539 	case SIOCX25GCAUSEDIAG: {
1540 		lock_sock(sk);
1541 		rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1542 			? -EFAULT : 0;
1543 		release_sock(sk);
1544 		break;
1545 	}
1546 
1547 	case SIOCX25SCAUSEDIAG: {
1548 		struct x25_causediag causediag;
1549 		rc = -EFAULT;
1550 		if (copy_from_user(&causediag, argp, sizeof(causediag)))
1551 			break;
1552 		lock_sock(sk);
1553 		x25->causediag = causediag;
1554 		release_sock(sk);
1555 		rc = 0;
1556 		break;
1557 
1558 	}
1559 
1560 	case SIOCX25SCUDMATCHLEN: {
1561 		struct x25_subaddr sub_addr;
1562 		rc = -EINVAL;
1563 		lock_sock(sk);
1564 		if(sk->sk_state != TCP_CLOSE)
1565 			goto out_cud_release;
1566 		rc = -EFAULT;
1567 		if (copy_from_user(&sub_addr, argp,
1568 				   sizeof(sub_addr)))
1569 			goto out_cud_release;
1570 		rc = -EINVAL;
1571 		if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1572 			goto out_cud_release;
1573 		x25->cudmatchlength = sub_addr.cudmatchlength;
1574 		rc = 0;
1575 out_cud_release:
1576 		release_sock(sk);
1577 		break;
1578 	}
1579 
1580 	case SIOCX25CALLACCPTAPPRV: {
1581 		rc = -EINVAL;
1582 		lock_sock(sk);
1583 		if (sk->sk_state == TCP_CLOSE) {
1584 			clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1585 			rc = 0;
1586 		}
1587 		release_sock(sk);
1588 		break;
1589 	}
1590 
1591 	case SIOCX25SENDCALLACCPT:  {
1592 		rc = -EINVAL;
1593 		lock_sock(sk);
1594 		if (sk->sk_state != TCP_ESTABLISHED)
1595 			goto out_sendcallaccpt_release;
1596 		/* must call accptapprv above */
1597 		if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1598 			goto out_sendcallaccpt_release;
1599 		x25_write_internal(sk, X25_CALL_ACCEPTED);
1600 		x25->state = X25_STATE_3;
1601 		rc = 0;
1602 out_sendcallaccpt_release:
1603 		release_sock(sk);
1604 		break;
1605 	}
1606 
1607 	default:
1608 		rc = -ENOIOCTLCMD;
1609 		break;
1610 	}
1611 
1612 	return rc;
1613 }
1614 
1615 static const struct net_proto_family x25_family_ops = {
1616 	.family =	AF_X25,
1617 	.create =	x25_create,
1618 	.owner	=	THIS_MODULE,
1619 };
1620 
1621 #ifdef CONFIG_COMPAT
1622 static int compat_x25_subscr_ioctl(unsigned int cmd,
1623 		struct compat_x25_subscrip_struct __user *x25_subscr32)
1624 {
1625 	struct compat_x25_subscrip_struct x25_subscr;
1626 	struct x25_neigh *nb;
1627 	struct net_device *dev;
1628 	int rc = -EINVAL;
1629 
1630 	rc = -EFAULT;
1631 	if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1632 		goto out;
1633 
1634 	rc = -EINVAL;
1635 	dev = x25_dev_get(x25_subscr.device);
1636 	if (dev == NULL)
1637 		goto out;
1638 
1639 	nb = x25_get_neigh(dev);
1640 	if (nb == NULL)
1641 		goto out_dev_put;
1642 
1643 	dev_put(dev);
1644 
1645 	if (cmd == SIOCX25GSUBSCRIP) {
1646 		read_lock_bh(&x25_neigh_list_lock);
1647 		x25_subscr.extended = nb->extended;
1648 		x25_subscr.global_facil_mask = nb->global_facil_mask;
1649 		read_unlock_bh(&x25_neigh_list_lock);
1650 		rc = copy_to_user(x25_subscr32, &x25_subscr,
1651 				sizeof(*x25_subscr32)) ? -EFAULT : 0;
1652 	} else {
1653 		rc = -EINVAL;
1654 		if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1655 			rc = 0;
1656 			write_lock_bh(&x25_neigh_list_lock);
1657 			nb->extended = x25_subscr.extended;
1658 			nb->global_facil_mask = x25_subscr.global_facil_mask;
1659 			write_unlock_bh(&x25_neigh_list_lock);
1660 		}
1661 	}
1662 	x25_neigh_put(nb);
1663 out:
1664 	return rc;
1665 out_dev_put:
1666 	dev_put(dev);
1667 	goto out;
1668 }
1669 
1670 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1671 				unsigned long arg)
1672 {
1673 	void __user *argp = compat_ptr(arg);
1674 	struct sock *sk = sock->sk;
1675 
1676 	int rc = -ENOIOCTLCMD;
1677 
1678 	switch(cmd) {
1679 	case TIOCOUTQ:
1680 	case TIOCINQ:
1681 		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1682 		break;
1683 	case SIOCGSTAMP:
1684 		rc = -EINVAL;
1685 		if (sk)
1686 			rc = compat_sock_get_timestamp(sk,
1687 					(struct timeval __user*)argp);
1688 		break;
1689 	case SIOCGSTAMPNS:
1690 		rc = -EINVAL;
1691 		if (sk)
1692 			rc = compat_sock_get_timestampns(sk,
1693 					(struct timespec __user*)argp);
1694 		break;
1695 	case SIOCGIFADDR:
1696 	case SIOCSIFADDR:
1697 	case SIOCGIFDSTADDR:
1698 	case SIOCSIFDSTADDR:
1699 	case SIOCGIFBRDADDR:
1700 	case SIOCSIFBRDADDR:
1701 	case SIOCGIFNETMASK:
1702 	case SIOCSIFNETMASK:
1703 	case SIOCGIFMETRIC:
1704 	case SIOCSIFMETRIC:
1705 		rc = -EINVAL;
1706 		break;
1707 	case SIOCADDRT:
1708 	case SIOCDELRT:
1709 		rc = -EPERM;
1710 		if (!capable(CAP_NET_ADMIN))
1711 			break;
1712 		rc = x25_route_ioctl(cmd, argp);
1713 		break;
1714 	case SIOCX25GSUBSCRIP:
1715 		rc = compat_x25_subscr_ioctl(cmd, argp);
1716 		break;
1717 	case SIOCX25SSUBSCRIP:
1718 		rc = -EPERM;
1719 		if (!capable(CAP_NET_ADMIN))
1720 			break;
1721 		rc = compat_x25_subscr_ioctl(cmd, argp);
1722 		break;
1723 	case SIOCX25GFACILITIES:
1724 	case SIOCX25SFACILITIES:
1725 	case SIOCX25GDTEFACILITIES:
1726 	case SIOCX25SDTEFACILITIES:
1727 	case SIOCX25GCALLUSERDATA:
1728 	case SIOCX25SCALLUSERDATA:
1729 	case SIOCX25GCAUSEDIAG:
1730 	case SIOCX25SCAUSEDIAG:
1731 	case SIOCX25SCUDMATCHLEN:
1732 	case SIOCX25CALLACCPTAPPRV:
1733 	case SIOCX25SENDCALLACCPT:
1734 		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1735 		break;
1736 	default:
1737 		rc = -ENOIOCTLCMD;
1738 		break;
1739 	}
1740 	return rc;
1741 }
1742 #endif
1743 
1744 static const struct proto_ops x25_proto_ops = {
1745 	.family =	AF_X25,
1746 	.owner =	THIS_MODULE,
1747 	.release =	x25_release,
1748 	.bind =		x25_bind,
1749 	.connect =	x25_connect,
1750 	.socketpair =	sock_no_socketpair,
1751 	.accept =	x25_accept,
1752 	.getname =	x25_getname,
1753 	.poll =		datagram_poll,
1754 	.ioctl =	x25_ioctl,
1755 #ifdef CONFIG_COMPAT
1756 	.compat_ioctl = compat_x25_ioctl,
1757 #endif
1758 	.listen =	x25_listen,
1759 	.shutdown =	sock_no_shutdown,
1760 	.setsockopt =	x25_setsockopt,
1761 	.getsockopt =	x25_getsockopt,
1762 	.sendmsg =	x25_sendmsg,
1763 	.recvmsg =	x25_recvmsg,
1764 	.mmap =		sock_no_mmap,
1765 	.sendpage =	sock_no_sendpage,
1766 };
1767 
1768 static struct packet_type x25_packet_type __read_mostly = {
1769 	.type =	cpu_to_be16(ETH_P_X25),
1770 	.func =	x25_lapb_receive_frame,
1771 };
1772 
1773 static struct notifier_block x25_dev_notifier = {
1774 	.notifier_call = x25_device_event,
1775 };
1776 
1777 void x25_kill_by_neigh(struct x25_neigh *nb)
1778 {
1779 	struct sock *s;
1780 
1781 	write_lock_bh(&x25_list_lock);
1782 
1783 	sk_for_each(s, &x25_list)
1784 		if (x25_sk(s)->neighbour == nb)
1785 			x25_disconnect(s, ENETUNREACH, 0, 0);
1786 
1787 	write_unlock_bh(&x25_list_lock);
1788 
1789 	/* Remove any related forwards */
1790 	x25_clear_forward_by_dev(nb->dev);
1791 }
1792 
1793 static int __init x25_init(void)
1794 {
1795 	int rc;
1796 
1797 	rc = proto_register(&x25_proto, 0);
1798 	if (rc)
1799 		goto out;
1800 
1801 	rc = sock_register(&x25_family_ops);
1802 	if (rc)
1803 		goto out_proto;
1804 
1805 	dev_add_pack(&x25_packet_type);
1806 
1807 	rc = register_netdevice_notifier(&x25_dev_notifier);
1808 	if (rc)
1809 		goto out_sock;
1810 
1811 	rc = x25_register_sysctl();
1812 	if (rc)
1813 		goto out_dev;
1814 
1815 	rc = x25_proc_init();
1816 	if (rc)
1817 		goto out_sysctl;
1818 
1819 	pr_info("Linux Version 0.2\n");
1820 
1821 out:
1822 	return rc;
1823 out_sysctl:
1824 	x25_unregister_sysctl();
1825 out_dev:
1826 	unregister_netdevice_notifier(&x25_dev_notifier);
1827 out_sock:
1828 	dev_remove_pack(&x25_packet_type);
1829 	sock_unregister(AF_X25);
1830 out_proto:
1831 	proto_unregister(&x25_proto);
1832 	goto out;
1833 }
1834 module_init(x25_init);
1835 
1836 static void __exit x25_exit(void)
1837 {
1838 	x25_proc_exit();
1839 	x25_link_free();
1840 	x25_route_free();
1841 
1842 	x25_unregister_sysctl();
1843 
1844 	unregister_netdevice_notifier(&x25_dev_notifier);
1845 
1846 	dev_remove_pack(&x25_packet_type);
1847 
1848 	sock_unregister(AF_X25);
1849 	proto_unregister(&x25_proto);
1850 }
1851 module_exit(x25_exit);
1852 
1853 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1854 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1855 MODULE_LICENSE("GPL");
1856 MODULE_ALIAS_NETPROTO(PF_X25);
1857