xref: /linux/net/x25/af_x25.c (revision d257f9bf06129613de539ea71ecea60848b662cd)
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 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(unsigned long data)
378 {
379 	x25_destroy_socket_from_timer((struct sock *)data);
380 }
381 
382 /*
383  *	This is called from user mode and the timers. Thus it protects itself
384  *	against interrupt users but doesn't worry about being called during
385  *	work. Once it is removed from the queue no interrupt or bottom half
386  *	will touch it and we are (fairly 8-) ) safe.
387  *	Not static as it's used by the timer
388  */
389 static void __x25_destroy_socket(struct sock *sk)
390 {
391 	struct sk_buff *skb;
392 
393 	x25_stop_heartbeat(sk);
394 	x25_stop_timer(sk);
395 
396 	x25_remove_socket(sk);
397 	x25_clear_queues(sk);		/* Flush the queues */
398 
399 	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
400 		if (skb->sk != sk) {		/* A pending connection */
401 			/*
402 			 * Queue the unaccepted socket for death
403 			 */
404 			skb->sk->sk_state = TCP_LISTEN;
405 			sock_set_flag(skb->sk, SOCK_DEAD);
406 			x25_start_heartbeat(skb->sk);
407 			x25_sk(skb->sk)->state = X25_STATE_0;
408 		}
409 
410 		kfree_skb(skb);
411 	}
412 
413 	if (sk_has_allocations(sk)) {
414 		/* Defer: outstanding buffers */
415 		sk->sk_timer.expires  = jiffies + 10 * HZ;
416 		sk->sk_timer.function = x25_destroy_timer;
417 		sk->sk_timer.data = (unsigned long)sk;
418 		add_timer(&sk->sk_timer);
419 	} else {
420 		/* drop last reference so sock_put will free */
421 		__sock_put(sk);
422 	}
423 }
424 
425 void x25_destroy_socket_from_timer(struct sock *sk)
426 {
427 	sock_hold(sk);
428 	bh_lock_sock(sk);
429 	__x25_destroy_socket(sk);
430 	bh_unlock_sock(sk);
431 	sock_put(sk);
432 }
433 
434 /*
435  *	Handling for system calls applied via the various interfaces to a
436  *	X.25 socket object.
437  */
438 
439 static int x25_setsockopt(struct socket *sock, int level, int optname,
440 			  char __user *optval, unsigned int optlen)
441 {
442 	int opt;
443 	struct sock *sk = sock->sk;
444 	int rc = -ENOPROTOOPT;
445 
446 	if (level != SOL_X25 || optname != X25_QBITINCL)
447 		goto out;
448 
449 	rc = -EINVAL;
450 	if (optlen < sizeof(int))
451 		goto out;
452 
453 	rc = -EFAULT;
454 	if (get_user(opt, (int __user *)optval))
455 		goto out;
456 
457 	if (opt)
458 		set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
459 	else
460 		clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
461 	rc = 0;
462 out:
463 	return rc;
464 }
465 
466 static int x25_getsockopt(struct socket *sock, int level, int optname,
467 			  char __user *optval, int __user *optlen)
468 {
469 	struct sock *sk = sock->sk;
470 	int val, len, rc = -ENOPROTOOPT;
471 
472 	if (level != SOL_X25 || optname != X25_QBITINCL)
473 		goto out;
474 
475 	rc = -EFAULT;
476 	if (get_user(len, optlen))
477 		goto out;
478 
479 	len = min_t(unsigned int, len, sizeof(int));
480 
481 	rc = -EINVAL;
482 	if (len < 0)
483 		goto out;
484 
485 	rc = -EFAULT;
486 	if (put_user(len, optlen))
487 		goto out;
488 
489 	val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
490 	rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
491 out:
492 	return rc;
493 }
494 
495 static int x25_listen(struct socket *sock, int backlog)
496 {
497 	struct sock *sk = sock->sk;
498 	int rc = -EOPNOTSUPP;
499 
500 	lock_sock(sk);
501 	if (sk->sk_state != TCP_LISTEN) {
502 		memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
503 		sk->sk_max_ack_backlog = backlog;
504 		sk->sk_state           = TCP_LISTEN;
505 		rc = 0;
506 	}
507 	release_sock(sk);
508 
509 	return rc;
510 }
511 
512 static struct proto x25_proto = {
513 	.name	  = "X25",
514 	.owner	  = THIS_MODULE,
515 	.obj_size = sizeof(struct x25_sock),
516 };
517 
518 static struct sock *x25_alloc_socket(struct net *net, int kern)
519 {
520 	struct x25_sock *x25;
521 	struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
522 
523 	if (!sk)
524 		goto out;
525 
526 	sock_init_data(NULL, sk);
527 
528 	x25 = x25_sk(sk);
529 	skb_queue_head_init(&x25->ack_queue);
530 	skb_queue_head_init(&x25->fragment_queue);
531 	skb_queue_head_init(&x25->interrupt_in_queue);
532 	skb_queue_head_init(&x25->interrupt_out_queue);
533 out:
534 	return sk;
535 }
536 
537 static int x25_create(struct net *net, struct socket *sock, int protocol,
538 		      int kern)
539 {
540 	struct sock *sk;
541 	struct x25_sock *x25;
542 	int rc = -EAFNOSUPPORT;
543 
544 	if (!net_eq(net, &init_net))
545 		goto out;
546 
547 	rc = -ESOCKTNOSUPPORT;
548 	if (sock->type != SOCK_SEQPACKET)
549 		goto out;
550 
551 	rc = -EINVAL;
552 	if (protocol)
553 		goto out;
554 
555 	rc = -ENOBUFS;
556 	if ((sk = x25_alloc_socket(net, kern)) == NULL)
557 		goto out;
558 
559 	x25 = x25_sk(sk);
560 
561 	sock_init_data(sock, sk);
562 
563 	x25_init_timers(sk);
564 
565 	sock->ops    = &x25_proto_ops;
566 	sk->sk_protocol = protocol;
567 	sk->sk_backlog_rcv = x25_backlog_rcv;
568 
569 	x25->t21   = sysctl_x25_call_request_timeout;
570 	x25->t22   = sysctl_x25_reset_request_timeout;
571 	x25->t23   = sysctl_x25_clear_request_timeout;
572 	x25->t2    = sysctl_x25_ack_holdback_timeout;
573 	x25->state = X25_STATE_0;
574 	x25->cudmatchlength = 0;
575 	set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);	/* normally no cud  */
576 							/* on call accept   */
577 
578 	x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
579 	x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
580 	x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
581 	x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
582 	x25->facilities.throughput  = 0;	/* by default don't negotiate
583 						   throughput */
584 	x25->facilities.reverse     = X25_DEFAULT_REVERSE;
585 	x25->dte_facilities.calling_len = 0;
586 	x25->dte_facilities.called_len = 0;
587 	memset(x25->dte_facilities.called_ae, '\0',
588 			sizeof(x25->dte_facilities.called_ae));
589 	memset(x25->dte_facilities.calling_ae, '\0',
590 			sizeof(x25->dte_facilities.calling_ae));
591 
592 	rc = 0;
593 out:
594 	return rc;
595 }
596 
597 static struct sock *x25_make_new(struct sock *osk)
598 {
599 	struct sock *sk = NULL;
600 	struct x25_sock *x25, *ox25;
601 
602 	if (osk->sk_type != SOCK_SEQPACKET)
603 		goto out;
604 
605 	if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
606 		goto out;
607 
608 	x25 = x25_sk(sk);
609 
610 	sk->sk_type        = osk->sk_type;
611 	sk->sk_priority    = osk->sk_priority;
612 	sk->sk_protocol    = osk->sk_protocol;
613 	sk->sk_rcvbuf      = osk->sk_rcvbuf;
614 	sk->sk_sndbuf      = osk->sk_sndbuf;
615 	sk->sk_state       = TCP_ESTABLISHED;
616 	sk->sk_backlog_rcv = osk->sk_backlog_rcv;
617 	sock_copy_flags(sk, osk);
618 
619 	ox25 = x25_sk(osk);
620 	x25->t21        = ox25->t21;
621 	x25->t22        = ox25->t22;
622 	x25->t23        = ox25->t23;
623 	x25->t2         = ox25->t2;
624 	x25->flags	= ox25->flags;
625 	x25->facilities = ox25->facilities;
626 	x25->dte_facilities = ox25->dte_facilities;
627 	x25->cudmatchlength = ox25->cudmatchlength;
628 
629 	clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
630 	x25_init_timers(sk);
631 out:
632 	return sk;
633 }
634 
635 static int x25_release(struct socket *sock)
636 {
637 	struct sock *sk = sock->sk;
638 	struct x25_sock *x25;
639 
640 	if (!sk)
641 		return 0;
642 
643 	x25 = x25_sk(sk);
644 
645 	sock_hold(sk);
646 	lock_sock(sk);
647 	switch (x25->state) {
648 
649 		case X25_STATE_0:
650 		case X25_STATE_2:
651 			x25_disconnect(sk, 0, 0, 0);
652 			__x25_destroy_socket(sk);
653 			goto out;
654 
655 		case X25_STATE_1:
656 		case X25_STATE_3:
657 		case X25_STATE_4:
658 			x25_clear_queues(sk);
659 			x25_write_internal(sk, X25_CLEAR_REQUEST);
660 			x25_start_t23timer(sk);
661 			x25->state = X25_STATE_2;
662 			sk->sk_state	= TCP_CLOSE;
663 			sk->sk_shutdown	|= SEND_SHUTDOWN;
664 			sk->sk_state_change(sk);
665 			sock_set_flag(sk, SOCK_DEAD);
666 			sock_set_flag(sk, SOCK_DESTROY);
667 			break;
668 	}
669 
670 	sock_orphan(sk);
671 out:
672 	release_sock(sk);
673 	sock_put(sk);
674 	return 0;
675 }
676 
677 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
678 {
679 	struct sock *sk = sock->sk;
680 	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
681 	int len, i, rc = 0;
682 
683 	if (!sock_flag(sk, SOCK_ZAPPED) ||
684 	    addr_len != sizeof(struct sockaddr_x25) ||
685 	    addr->sx25_family != AF_X25) {
686 		rc = -EINVAL;
687 		goto out;
688 	}
689 
690 	len = strlen(addr->sx25_addr.x25_addr);
691 	for (i = 0; i < len; i++) {
692 		if (!isdigit(addr->sx25_addr.x25_addr[i])) {
693 			rc = -EINVAL;
694 			goto out;
695 		}
696 	}
697 
698 	lock_sock(sk);
699 	x25_sk(sk)->source_addr = addr->sx25_addr;
700 	x25_insert_socket(sk);
701 	sock_reset_flag(sk, SOCK_ZAPPED);
702 	release_sock(sk);
703 	SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
704 out:
705 	return rc;
706 }
707 
708 static int x25_wait_for_connection_establishment(struct sock *sk)
709 {
710 	DECLARE_WAITQUEUE(wait, current);
711 	int rc;
712 
713 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
714 	for (;;) {
715 		__set_current_state(TASK_INTERRUPTIBLE);
716 		rc = -ERESTARTSYS;
717 		if (signal_pending(current))
718 			break;
719 		rc = sock_error(sk);
720 		if (rc) {
721 			sk->sk_socket->state = SS_UNCONNECTED;
722 			break;
723 		}
724 		rc = 0;
725 		if (sk->sk_state != TCP_ESTABLISHED) {
726 			release_sock(sk);
727 			schedule();
728 			lock_sock(sk);
729 		} else
730 			break;
731 	}
732 	__set_current_state(TASK_RUNNING);
733 	remove_wait_queue(sk_sleep(sk), &wait);
734 	return rc;
735 }
736 
737 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
738 		       int addr_len, int flags)
739 {
740 	struct sock *sk = sock->sk;
741 	struct x25_sock *x25 = x25_sk(sk);
742 	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
743 	struct x25_route *rt;
744 	int rc = 0;
745 
746 	lock_sock(sk);
747 	if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
748 		sock->state = SS_CONNECTED;
749 		goto out; /* Connect completed during a ERESTARTSYS event */
750 	}
751 
752 	rc = -ECONNREFUSED;
753 	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
754 		sock->state = SS_UNCONNECTED;
755 		goto out;
756 	}
757 
758 	rc = -EISCONN;	/* No reconnect on a seqpacket socket */
759 	if (sk->sk_state == TCP_ESTABLISHED)
760 		goto out;
761 
762 	sk->sk_state   = TCP_CLOSE;
763 	sock->state = SS_UNCONNECTED;
764 
765 	rc = -EINVAL;
766 	if (addr_len != sizeof(struct sockaddr_x25) ||
767 	    addr->sx25_family != AF_X25)
768 		goto out;
769 
770 	rc = -ENETUNREACH;
771 	rt = x25_get_route(&addr->sx25_addr);
772 	if (!rt)
773 		goto out;
774 
775 	x25->neighbour = x25_get_neigh(rt->dev);
776 	if (!x25->neighbour)
777 		goto out_put_route;
778 
779 	x25_limit_facilities(&x25->facilities, x25->neighbour);
780 
781 	x25->lci = x25_new_lci(x25->neighbour);
782 	if (!x25->lci)
783 		goto out_put_neigh;
784 
785 	rc = -EINVAL;
786 	if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
787 		goto out_put_neigh;
788 
789 	if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
790 		memset(&x25->source_addr, '\0', X25_ADDR_LEN);
791 
792 	x25->dest_addr = addr->sx25_addr;
793 
794 	/* Move to connecting socket, start sending Connect Requests */
795 	sock->state   = SS_CONNECTING;
796 	sk->sk_state  = TCP_SYN_SENT;
797 
798 	x25->state = X25_STATE_1;
799 
800 	x25_write_internal(sk, X25_CALL_REQUEST);
801 
802 	x25_start_heartbeat(sk);
803 	x25_start_t21timer(sk);
804 
805 	/* Now the loop */
806 	rc = -EINPROGRESS;
807 	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
808 		goto out_put_neigh;
809 
810 	rc = x25_wait_for_connection_establishment(sk);
811 	if (rc)
812 		goto out_put_neigh;
813 
814 	sock->state = SS_CONNECTED;
815 	rc = 0;
816 out_put_neigh:
817 	if (rc)
818 		x25_neigh_put(x25->neighbour);
819 out_put_route:
820 	x25_route_put(rt);
821 out:
822 	release_sock(sk);
823 	return rc;
824 }
825 
826 static int x25_wait_for_data(struct sock *sk, long timeout)
827 {
828 	DECLARE_WAITQUEUE(wait, current);
829 	int rc = 0;
830 
831 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
832 	for (;;) {
833 		__set_current_state(TASK_INTERRUPTIBLE);
834 		if (sk->sk_shutdown & RCV_SHUTDOWN)
835 			break;
836 		rc = -ERESTARTSYS;
837 		if (signal_pending(current))
838 			break;
839 		rc = -EAGAIN;
840 		if (!timeout)
841 			break;
842 		rc = 0;
843 		if (skb_queue_empty(&sk->sk_receive_queue)) {
844 			release_sock(sk);
845 			timeout = schedule_timeout(timeout);
846 			lock_sock(sk);
847 		} else
848 			break;
849 	}
850 	__set_current_state(TASK_RUNNING);
851 	remove_wait_queue(sk_sleep(sk), &wait);
852 	return rc;
853 }
854 
855 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
856 		      bool kern)
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);
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 socket *sock, struct msghdr *msg, size_t len)
1082 {
1083 	struct sock *sk = sock->sk;
1084 	struct x25_sock *x25 = x25_sk(sk);
1085 	DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1086 	struct sockaddr_x25 sx25;
1087 	struct sk_buff *skb;
1088 	unsigned char *asmptr;
1089 	int noblock = msg->msg_flags & MSG_DONTWAIT;
1090 	size_t size;
1091 	int qbit = 0, rc = -EINVAL;
1092 
1093 	lock_sock(sk);
1094 	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1095 		goto out;
1096 
1097 	/* we currently don't support segmented records at the user interface */
1098 	if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1099 		goto out;
1100 
1101 	rc = -EADDRNOTAVAIL;
1102 	if (sock_flag(sk, SOCK_ZAPPED))
1103 		goto out;
1104 
1105 	rc = -EPIPE;
1106 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1107 		send_sig(SIGPIPE, current, 0);
1108 		goto out;
1109 	}
1110 
1111 	rc = -ENETUNREACH;
1112 	if (!x25->neighbour)
1113 		goto out;
1114 
1115 	if (usx25) {
1116 		rc = -EINVAL;
1117 		if (msg->msg_namelen < sizeof(sx25))
1118 			goto out;
1119 		memcpy(&sx25, usx25, sizeof(sx25));
1120 		rc = -EISCONN;
1121 		if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1122 			goto out;
1123 		rc = -EINVAL;
1124 		if (sx25.sx25_family != AF_X25)
1125 			goto out;
1126 	} else {
1127 		/*
1128 		 *	FIXME 1003.1g - if the socket is like this because
1129 		 *	it has become closed (not started closed) we ought
1130 		 *	to SIGPIPE, EPIPE;
1131 		 */
1132 		rc = -ENOTCONN;
1133 		if (sk->sk_state != TCP_ESTABLISHED)
1134 			goto out;
1135 
1136 		sx25.sx25_family = AF_X25;
1137 		sx25.sx25_addr   = x25->dest_addr;
1138 	}
1139 
1140 	/* Sanity check the packet size */
1141 	if (len > 65535) {
1142 		rc = -EMSGSIZE;
1143 		goto out;
1144 	}
1145 
1146 	SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1147 
1148 	/* Build a packet */
1149 	SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1150 
1151 	if ((msg->msg_flags & MSG_OOB) && len > 32)
1152 		len = 32;
1153 
1154 	size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1155 
1156 	release_sock(sk);
1157 	skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1158 	lock_sock(sk);
1159 	if (!skb)
1160 		goto out;
1161 	X25_SKB_CB(skb)->flags = msg->msg_flags;
1162 
1163 	skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1164 
1165 	/*
1166 	 *	Put the data on the end
1167 	 */
1168 	SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1169 
1170 	skb_reset_transport_header(skb);
1171 	skb_put(skb, len);
1172 
1173 	rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1174 	if (rc)
1175 		goto out_kfree_skb;
1176 
1177 	/*
1178 	 *	If the Q BIT Include socket option is in force, the first
1179 	 *	byte of the user data is the logical value of the Q Bit.
1180 	 */
1181 	if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1182 		if (!pskb_may_pull(skb, 1))
1183 			goto out_kfree_skb;
1184 
1185 		qbit = skb->data[0];
1186 		skb_pull(skb, 1);
1187 	}
1188 
1189 	/*
1190 	 *	Push down the X.25 header
1191 	 */
1192 	SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1193 
1194 	if (msg->msg_flags & MSG_OOB) {
1195 		if (x25->neighbour->extended) {
1196 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1197 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1198 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1199 			*asmptr++ = X25_INTERRUPT;
1200 		} else {
1201 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1202 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1203 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1204 			*asmptr++ = X25_INTERRUPT;
1205 		}
1206 	} else {
1207 		if (x25->neighbour->extended) {
1208 			/* Build an Extended X.25 header */
1209 			asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1210 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1211 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1212 			*asmptr++ = X25_DATA;
1213 			*asmptr++ = X25_DATA;
1214 		} else {
1215 			/* Build an Standard X.25 header */
1216 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1217 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1218 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1219 			*asmptr++ = X25_DATA;
1220 		}
1221 
1222 		if (qbit)
1223 			skb->data[0] |= X25_Q_BIT;
1224 	}
1225 
1226 	SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1227 	SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1228 
1229 	rc = -ENOTCONN;
1230 	if (sk->sk_state != TCP_ESTABLISHED)
1231 		goto out_kfree_skb;
1232 
1233 	if (msg->msg_flags & MSG_OOB)
1234 		skb_queue_tail(&x25->interrupt_out_queue, skb);
1235 	else {
1236 		rc = x25_output(sk, skb);
1237 		len = rc;
1238 		if (rc < 0)
1239 			kfree_skb(skb);
1240 		else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1241 			len++;
1242 	}
1243 
1244 	x25_kick(sk);
1245 	rc = len;
1246 out:
1247 	release_sock(sk);
1248 	return rc;
1249 out_kfree_skb:
1250 	kfree_skb(skb);
1251 	goto out;
1252 }
1253 
1254 
1255 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1256 		       int flags)
1257 {
1258 	struct sock *sk = sock->sk;
1259 	struct x25_sock *x25 = x25_sk(sk);
1260 	DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1261 	size_t copied;
1262 	int qbit, header_len;
1263 	struct sk_buff *skb;
1264 	unsigned char *asmptr;
1265 	int rc = -ENOTCONN;
1266 
1267 	lock_sock(sk);
1268 
1269 	if (x25->neighbour == NULL)
1270 		goto out;
1271 
1272 	header_len = x25->neighbour->extended ?
1273 		X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1274 
1275 	/*
1276 	 * This works for seqpacket too. The receiver has ordered the queue for
1277 	 * us! We do one quick check first though
1278 	 */
1279 	if (sk->sk_state != TCP_ESTABLISHED)
1280 		goto out;
1281 
1282 	if (flags & MSG_OOB) {
1283 		rc = -EINVAL;
1284 		if (sock_flag(sk, SOCK_URGINLINE) ||
1285 		    !skb_peek(&x25->interrupt_in_queue))
1286 			goto out;
1287 
1288 		skb = skb_dequeue(&x25->interrupt_in_queue);
1289 
1290 		if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1291 			goto out_free_dgram;
1292 
1293 		skb_pull(skb, X25_STD_MIN_LEN);
1294 
1295 		/*
1296 		 *	No Q bit information on Interrupt data.
1297 		 */
1298 		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1299 			asmptr  = skb_push(skb, 1);
1300 			*asmptr = 0x00;
1301 		}
1302 
1303 		msg->msg_flags |= MSG_OOB;
1304 	} else {
1305 		/* Now we can treat all alike */
1306 		release_sock(sk);
1307 		skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1308 					flags & MSG_DONTWAIT, &rc);
1309 		lock_sock(sk);
1310 		if (!skb)
1311 			goto out;
1312 
1313 		if (!pskb_may_pull(skb, header_len))
1314 			goto out_free_dgram;
1315 
1316 		qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1317 
1318 		skb_pull(skb, header_len);
1319 
1320 		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1321 			asmptr  = skb_push(skb, 1);
1322 			*asmptr = qbit;
1323 		}
1324 	}
1325 
1326 	skb_reset_transport_header(skb);
1327 	copied = skb->len;
1328 
1329 	if (copied > size) {
1330 		copied = size;
1331 		msg->msg_flags |= MSG_TRUNC;
1332 	}
1333 
1334 	/* Currently, each datagram always contains a complete record */
1335 	msg->msg_flags |= MSG_EOR;
1336 
1337 	rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1338 	if (rc)
1339 		goto out_free_dgram;
1340 
1341 	if (sx25) {
1342 		sx25->sx25_family = AF_X25;
1343 		sx25->sx25_addr   = x25->dest_addr;
1344 		msg->msg_namelen = sizeof(*sx25);
1345 	}
1346 
1347 	x25_check_rbuf(sk);
1348 	rc = copied;
1349 out_free_dgram:
1350 	skb_free_datagram(sk, skb);
1351 out:
1352 	release_sock(sk);
1353 	return rc;
1354 }
1355 
1356 
1357 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1358 {
1359 	struct sock *sk = sock->sk;
1360 	struct x25_sock *x25 = x25_sk(sk);
1361 	void __user *argp = (void __user *)arg;
1362 	int rc;
1363 
1364 	switch (cmd) {
1365 	case TIOCOUTQ: {
1366 		int amount;
1367 
1368 		amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1369 		if (amount < 0)
1370 			amount = 0;
1371 		rc = put_user(amount, (unsigned int __user *)argp);
1372 		break;
1373 	}
1374 
1375 	case TIOCINQ: {
1376 		struct sk_buff *skb;
1377 		int amount = 0;
1378 		/*
1379 		 * These two are safe on a single CPU system as
1380 		 * only user tasks fiddle here
1381 		 */
1382 		lock_sock(sk);
1383 		if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1384 			amount = skb->len;
1385 		release_sock(sk);
1386 		rc = put_user(amount, (unsigned int __user *)argp);
1387 		break;
1388 	}
1389 
1390 	case SIOCGSTAMP:
1391 		rc = -EINVAL;
1392 		if (sk)
1393 			rc = sock_get_timestamp(sk,
1394 						(struct timeval __user *)argp);
1395 		break;
1396 	case SIOCGSTAMPNS:
1397 		rc = -EINVAL;
1398 		if (sk)
1399 			rc = sock_get_timestampns(sk,
1400 					(struct timespec __user *)argp);
1401 		break;
1402 	case SIOCGIFADDR:
1403 	case SIOCSIFADDR:
1404 	case SIOCGIFDSTADDR:
1405 	case SIOCSIFDSTADDR:
1406 	case SIOCGIFBRDADDR:
1407 	case SIOCSIFBRDADDR:
1408 	case SIOCGIFNETMASK:
1409 	case SIOCSIFNETMASK:
1410 	case SIOCGIFMETRIC:
1411 	case SIOCSIFMETRIC:
1412 		rc = -EINVAL;
1413 		break;
1414 	case SIOCADDRT:
1415 	case SIOCDELRT:
1416 		rc = -EPERM;
1417 		if (!capable(CAP_NET_ADMIN))
1418 			break;
1419 		rc = x25_route_ioctl(cmd, argp);
1420 		break;
1421 	case SIOCX25GSUBSCRIP:
1422 		rc = x25_subscr_ioctl(cmd, argp);
1423 		break;
1424 	case SIOCX25SSUBSCRIP:
1425 		rc = -EPERM;
1426 		if (!capable(CAP_NET_ADMIN))
1427 			break;
1428 		rc = x25_subscr_ioctl(cmd, argp);
1429 		break;
1430 	case SIOCX25GFACILITIES: {
1431 		lock_sock(sk);
1432 		rc = copy_to_user(argp, &x25->facilities,
1433 				  sizeof(x25->facilities))
1434 			? -EFAULT : 0;
1435 		release_sock(sk);
1436 		break;
1437 	}
1438 
1439 	case SIOCX25SFACILITIES: {
1440 		struct x25_facilities facilities;
1441 		rc = -EFAULT;
1442 		if (copy_from_user(&facilities, argp, sizeof(facilities)))
1443 			break;
1444 		rc = -EINVAL;
1445 		lock_sock(sk);
1446 		if (sk->sk_state != TCP_LISTEN &&
1447 		    sk->sk_state != TCP_CLOSE)
1448 			goto out_fac_release;
1449 		if (facilities.pacsize_in < X25_PS16 ||
1450 		    facilities.pacsize_in > X25_PS4096)
1451 			goto out_fac_release;
1452 		if (facilities.pacsize_out < X25_PS16 ||
1453 		    facilities.pacsize_out > X25_PS4096)
1454 			goto out_fac_release;
1455 		if (facilities.winsize_in < 1 ||
1456 		    facilities.winsize_in > 127)
1457 			goto out_fac_release;
1458 		if (facilities.throughput) {
1459 			int out = facilities.throughput & 0xf0;
1460 			int in  = facilities.throughput & 0x0f;
1461 			if (!out)
1462 				facilities.throughput |=
1463 					X25_DEFAULT_THROUGHPUT << 4;
1464 			else if (out < 0x30 || out > 0xD0)
1465 				goto out_fac_release;
1466 			if (!in)
1467 				facilities.throughput |=
1468 					X25_DEFAULT_THROUGHPUT;
1469 			else if (in < 0x03 || in > 0x0D)
1470 				goto out_fac_release;
1471 		}
1472 		if (facilities.reverse &&
1473 		    (facilities.reverse & 0x81) != 0x81)
1474 			goto out_fac_release;
1475 		x25->facilities = facilities;
1476 		rc = 0;
1477 out_fac_release:
1478 		release_sock(sk);
1479 		break;
1480 	}
1481 
1482 	case SIOCX25GDTEFACILITIES: {
1483 		lock_sock(sk);
1484 		rc = copy_to_user(argp, &x25->dte_facilities,
1485 				  sizeof(x25->dte_facilities));
1486 		release_sock(sk);
1487 		if (rc)
1488 			rc = -EFAULT;
1489 		break;
1490 	}
1491 
1492 	case SIOCX25SDTEFACILITIES: {
1493 		struct x25_dte_facilities dtefacs;
1494 		rc = -EFAULT;
1495 		if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1496 			break;
1497 		rc = -EINVAL;
1498 		lock_sock(sk);
1499 		if (sk->sk_state != TCP_LISTEN &&
1500 		    sk->sk_state != TCP_CLOSE)
1501 			goto out_dtefac_release;
1502 		if (dtefacs.calling_len > X25_MAX_AE_LEN)
1503 			goto out_dtefac_release;
1504 		if (dtefacs.called_len > X25_MAX_AE_LEN)
1505 			goto out_dtefac_release;
1506 		x25->dte_facilities = dtefacs;
1507 		rc = 0;
1508 out_dtefac_release:
1509 		release_sock(sk);
1510 		break;
1511 	}
1512 
1513 	case SIOCX25GCALLUSERDATA: {
1514 		lock_sock(sk);
1515 		rc = copy_to_user(argp, &x25->calluserdata,
1516 				  sizeof(x25->calluserdata))
1517 			? -EFAULT : 0;
1518 		release_sock(sk);
1519 		break;
1520 	}
1521 
1522 	case SIOCX25SCALLUSERDATA: {
1523 		struct x25_calluserdata calluserdata;
1524 
1525 		rc = -EFAULT;
1526 		if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1527 			break;
1528 		rc = -EINVAL;
1529 		if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1530 			break;
1531 		lock_sock(sk);
1532 		x25->calluserdata = calluserdata;
1533 		release_sock(sk);
1534 		rc = 0;
1535 		break;
1536 	}
1537 
1538 	case SIOCX25GCAUSEDIAG: {
1539 		lock_sock(sk);
1540 		rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1541 			? -EFAULT : 0;
1542 		release_sock(sk);
1543 		break;
1544 	}
1545 
1546 	case SIOCX25SCAUSEDIAG: {
1547 		struct x25_causediag causediag;
1548 		rc = -EFAULT;
1549 		if (copy_from_user(&causediag, argp, sizeof(causediag)))
1550 			break;
1551 		lock_sock(sk);
1552 		x25->causediag = causediag;
1553 		release_sock(sk);
1554 		rc = 0;
1555 		break;
1556 
1557 	}
1558 
1559 	case SIOCX25SCUDMATCHLEN: {
1560 		struct x25_subaddr sub_addr;
1561 		rc = -EINVAL;
1562 		lock_sock(sk);
1563 		if(sk->sk_state != TCP_CLOSE)
1564 			goto out_cud_release;
1565 		rc = -EFAULT;
1566 		if (copy_from_user(&sub_addr, argp,
1567 				   sizeof(sub_addr)))
1568 			goto out_cud_release;
1569 		rc = -EINVAL;
1570 		if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1571 			goto out_cud_release;
1572 		x25->cudmatchlength = sub_addr.cudmatchlength;
1573 		rc = 0;
1574 out_cud_release:
1575 		release_sock(sk);
1576 		break;
1577 	}
1578 
1579 	case SIOCX25CALLACCPTAPPRV: {
1580 		rc = -EINVAL;
1581 		lock_sock(sk);
1582 		if (sk->sk_state == TCP_CLOSE) {
1583 			clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1584 			rc = 0;
1585 		}
1586 		release_sock(sk);
1587 		break;
1588 	}
1589 
1590 	case SIOCX25SENDCALLACCPT:  {
1591 		rc = -EINVAL;
1592 		lock_sock(sk);
1593 		if (sk->sk_state != TCP_ESTABLISHED)
1594 			goto out_sendcallaccpt_release;
1595 		/* must call accptapprv above */
1596 		if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1597 			goto out_sendcallaccpt_release;
1598 		x25_write_internal(sk, X25_CALL_ACCEPTED);
1599 		x25->state = X25_STATE_3;
1600 		rc = 0;
1601 out_sendcallaccpt_release:
1602 		release_sock(sk);
1603 		break;
1604 	}
1605 
1606 	default:
1607 		rc = -ENOIOCTLCMD;
1608 		break;
1609 	}
1610 
1611 	return rc;
1612 }
1613 
1614 static const struct net_proto_family x25_family_ops = {
1615 	.family =	AF_X25,
1616 	.create =	x25_create,
1617 	.owner	=	THIS_MODULE,
1618 };
1619 
1620 #ifdef CONFIG_COMPAT
1621 static int compat_x25_subscr_ioctl(unsigned int cmd,
1622 		struct compat_x25_subscrip_struct __user *x25_subscr32)
1623 {
1624 	struct compat_x25_subscrip_struct x25_subscr;
1625 	struct x25_neigh *nb;
1626 	struct net_device *dev;
1627 	int rc = -EINVAL;
1628 
1629 	rc = -EFAULT;
1630 	if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1631 		goto out;
1632 
1633 	rc = -EINVAL;
1634 	dev = x25_dev_get(x25_subscr.device);
1635 	if (dev == NULL)
1636 		goto out;
1637 
1638 	nb = x25_get_neigh(dev);
1639 	if (nb == NULL)
1640 		goto out_dev_put;
1641 
1642 	dev_put(dev);
1643 
1644 	if (cmd == SIOCX25GSUBSCRIP) {
1645 		read_lock_bh(&x25_neigh_list_lock);
1646 		x25_subscr.extended = nb->extended;
1647 		x25_subscr.global_facil_mask = nb->global_facil_mask;
1648 		read_unlock_bh(&x25_neigh_list_lock);
1649 		rc = copy_to_user(x25_subscr32, &x25_subscr,
1650 				sizeof(*x25_subscr32)) ? -EFAULT : 0;
1651 	} else {
1652 		rc = -EINVAL;
1653 		if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1654 			rc = 0;
1655 			write_lock_bh(&x25_neigh_list_lock);
1656 			nb->extended = x25_subscr.extended;
1657 			nb->global_facil_mask = x25_subscr.global_facil_mask;
1658 			write_unlock_bh(&x25_neigh_list_lock);
1659 		}
1660 	}
1661 	x25_neigh_put(nb);
1662 out:
1663 	return rc;
1664 out_dev_put:
1665 	dev_put(dev);
1666 	goto out;
1667 }
1668 
1669 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1670 				unsigned long arg)
1671 {
1672 	void __user *argp = compat_ptr(arg);
1673 	struct sock *sk = sock->sk;
1674 
1675 	int rc = -ENOIOCTLCMD;
1676 
1677 	switch(cmd) {
1678 	case TIOCOUTQ:
1679 	case TIOCINQ:
1680 		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1681 		break;
1682 	case SIOCGSTAMP:
1683 		rc = -EINVAL;
1684 		if (sk)
1685 			rc = compat_sock_get_timestamp(sk,
1686 					(struct timeval __user*)argp);
1687 		break;
1688 	case SIOCGSTAMPNS:
1689 		rc = -EINVAL;
1690 		if (sk)
1691 			rc = compat_sock_get_timestampns(sk,
1692 					(struct timespec __user*)argp);
1693 		break;
1694 	case SIOCGIFADDR:
1695 	case SIOCSIFADDR:
1696 	case SIOCGIFDSTADDR:
1697 	case SIOCSIFDSTADDR:
1698 	case SIOCGIFBRDADDR:
1699 	case SIOCSIFBRDADDR:
1700 	case SIOCGIFNETMASK:
1701 	case SIOCSIFNETMASK:
1702 	case SIOCGIFMETRIC:
1703 	case SIOCSIFMETRIC:
1704 		rc = -EINVAL;
1705 		break;
1706 	case SIOCADDRT:
1707 	case SIOCDELRT:
1708 		rc = -EPERM;
1709 		if (!capable(CAP_NET_ADMIN))
1710 			break;
1711 		rc = x25_route_ioctl(cmd, argp);
1712 		break;
1713 	case SIOCX25GSUBSCRIP:
1714 		rc = compat_x25_subscr_ioctl(cmd, argp);
1715 		break;
1716 	case SIOCX25SSUBSCRIP:
1717 		rc = -EPERM;
1718 		if (!capable(CAP_NET_ADMIN))
1719 			break;
1720 		rc = compat_x25_subscr_ioctl(cmd, argp);
1721 		break;
1722 	case SIOCX25GFACILITIES:
1723 	case SIOCX25SFACILITIES:
1724 	case SIOCX25GDTEFACILITIES:
1725 	case SIOCX25SDTEFACILITIES:
1726 	case SIOCX25GCALLUSERDATA:
1727 	case SIOCX25SCALLUSERDATA:
1728 	case SIOCX25GCAUSEDIAG:
1729 	case SIOCX25SCAUSEDIAG:
1730 	case SIOCX25SCUDMATCHLEN:
1731 	case SIOCX25CALLACCPTAPPRV:
1732 	case SIOCX25SENDCALLACCPT:
1733 		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1734 		break;
1735 	default:
1736 		rc = -ENOIOCTLCMD;
1737 		break;
1738 	}
1739 	return rc;
1740 }
1741 #endif
1742 
1743 static const struct proto_ops x25_proto_ops = {
1744 	.family =	AF_X25,
1745 	.owner =	THIS_MODULE,
1746 	.release =	x25_release,
1747 	.bind =		x25_bind,
1748 	.connect =	x25_connect,
1749 	.socketpair =	sock_no_socketpair,
1750 	.accept =	x25_accept,
1751 	.getname =	x25_getname,
1752 	.poll =		datagram_poll,
1753 	.ioctl =	x25_ioctl,
1754 #ifdef CONFIG_COMPAT
1755 	.compat_ioctl = compat_x25_ioctl,
1756 #endif
1757 	.listen =	x25_listen,
1758 	.shutdown =	sock_no_shutdown,
1759 	.setsockopt =	x25_setsockopt,
1760 	.getsockopt =	x25_getsockopt,
1761 	.sendmsg =	x25_sendmsg,
1762 	.recvmsg =	x25_recvmsg,
1763 	.mmap =		sock_no_mmap,
1764 	.sendpage =	sock_no_sendpage,
1765 };
1766 
1767 static struct packet_type x25_packet_type __read_mostly = {
1768 	.type =	cpu_to_be16(ETH_P_X25),
1769 	.func =	x25_lapb_receive_frame,
1770 };
1771 
1772 static struct notifier_block x25_dev_notifier = {
1773 	.notifier_call = x25_device_event,
1774 };
1775 
1776 void x25_kill_by_neigh(struct x25_neigh *nb)
1777 {
1778 	struct sock *s;
1779 
1780 	write_lock_bh(&x25_list_lock);
1781 
1782 	sk_for_each(s, &x25_list)
1783 		if (x25_sk(s)->neighbour == nb)
1784 			x25_disconnect(s, ENETUNREACH, 0, 0);
1785 
1786 	write_unlock_bh(&x25_list_lock);
1787 
1788 	/* Remove any related forwards */
1789 	x25_clear_forward_by_dev(nb->dev);
1790 }
1791 
1792 static int __init x25_init(void)
1793 {
1794 	int rc;
1795 
1796 	rc = proto_register(&x25_proto, 0);
1797 	if (rc)
1798 		goto out;
1799 
1800 	rc = sock_register(&x25_family_ops);
1801 	if (rc)
1802 		goto out_proto;
1803 
1804 	dev_add_pack(&x25_packet_type);
1805 
1806 	rc = register_netdevice_notifier(&x25_dev_notifier);
1807 	if (rc)
1808 		goto out_sock;
1809 
1810 	rc = x25_register_sysctl();
1811 	if (rc)
1812 		goto out_dev;
1813 
1814 	rc = x25_proc_init();
1815 	if (rc)
1816 		goto out_sysctl;
1817 
1818 	pr_info("Linux Version 0.2\n");
1819 
1820 out:
1821 	return rc;
1822 out_sysctl:
1823 	x25_unregister_sysctl();
1824 out_dev:
1825 	unregister_netdevice_notifier(&x25_dev_notifier);
1826 out_sock:
1827 	dev_remove_pack(&x25_packet_type);
1828 	sock_unregister(AF_X25);
1829 out_proto:
1830 	proto_unregister(&x25_proto);
1831 	goto out;
1832 }
1833 module_init(x25_init);
1834 
1835 static void __exit x25_exit(void)
1836 {
1837 	x25_proc_exit();
1838 	x25_link_free();
1839 	x25_route_free();
1840 
1841 	x25_unregister_sysctl();
1842 
1843 	unregister_netdevice_notifier(&x25_dev_notifier);
1844 
1845 	dev_remove_pack(&x25_packet_type);
1846 
1847 	sock_unregister(AF_X25);
1848 	proto_unregister(&x25_proto);
1849 }
1850 module_exit(x25_exit);
1851 
1852 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1853 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1854 MODULE_LICENSE("GPL");
1855 MODULE_ALIAS_NETPROTO(PF_X25);
1856