xref: /openbmc/linux/net/x25/af_x25.c (revision d23015c1)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	X.25 Packet Layer release 002
4  *
5  *	This is ALPHA test software. This code may break your machine,
6  *	randomly fail to work with new releases, misbehave and/or generally
7  *	screw up. It might even work.
8  *
9  *	This code REQUIRES 2.1.15 or higher
10  *
11  *	History
12  *	X.25 001	Jonathan Naylor	Started coding.
13  *	X.25 002	Jonathan Naylor	Centralised disconnect handling.
14  *					New timer architecture.
15  *	2000-03-11	Henner Eisen	MSG_EOR handling more POSIX compliant.
16  *	2000-03-22	Daniela Squassoni Allowed disabling/enabling of
17  *					  facilities negotiation and increased
18  *					  the throughput upper limit.
19  *	2000-08-27	Arnaldo C. Melo s/suser/capable/ + micro cleanups
20  *	2000-09-04	Henner Eisen	Set sock->state in x25_accept().
21  *					Fixed x25_output() related skb leakage.
22  *	2000-10-02	Henner Eisen	Made x25_kick() single threaded per socket.
23  *	2000-10-27	Henner Eisen    MSG_DONTWAIT for fragment allocation.
24  *	2000-11-14	Henner Eisen    Closing datalink from NETDEV_GOING_DOWN
25  *	2002-10-06	Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
26  *					x25_proc.c, using seq_file
27  *	2005-04-02	Shaun Pereira	Selective sub address matching
28  *					with call user data
29  *	2005-04-15	Shaun Pereira	Fast select with no restriction on
30  *					response
31  */
32 
33 #define pr_fmt(fmt) "X25: " fmt
34 
35 #include <linux/module.h>
36 #include <linux/capability.h>
37 #include <linux/errno.h>
38 #include <linux/kernel.h>
39 #include <linux/sched/signal.h>
40 #include <linux/timer.h>
41 #include <linux/string.h>
42 #include <linux/net.h>
43 #include <linux/netdevice.h>
44 #include <linux/if_arp.h>
45 #include <linux/skbuff.h>
46 #include <linux/slab.h>
47 #include <net/sock.h>
48 #include <net/tcp_states.h>
49 #include <linux/uaccess.h>
50 #include <linux/fcntl.h>
51 #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
52 #include <linux/notifier.h>
53 #include <linux/init.h>
54 #include <linux/compat.h>
55 #include <linux/ctype.h>
56 
57 #include <net/x25.h>
58 #include <net/compat.h>
59 
60 int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
61 int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
62 int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
63 int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
64 int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
65 int sysctl_x25_forward                 = 0;
66 
67 HLIST_HEAD(x25_list);
68 DEFINE_RWLOCK(x25_list_lock);
69 
70 static const struct proto_ops x25_proto_ops;
71 
72 static const struct x25_address null_x25_address = {"               "};
73 
74 #ifdef CONFIG_COMPAT
75 struct compat_x25_subscrip_struct {
76 	char device[200-sizeof(compat_ulong_t)];
77 	compat_ulong_t global_facil_mask;
78 	compat_uint_t extended;
79 };
80 #endif
81 
82 
83 int x25_parse_address_block(struct sk_buff *skb,
84 		struct x25_address *called_addr,
85 		struct x25_address *calling_addr)
86 {
87 	unsigned char len;
88 	int needed;
89 	int rc;
90 
91 	if (!pskb_may_pull(skb, 1)) {
92 		/* packet has no address block */
93 		rc = 0;
94 		goto empty;
95 	}
96 
97 	len = *skb->data;
98 	needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2;
99 
100 	if (!pskb_may_pull(skb, needed)) {
101 		/* packet is too short to hold the addresses it claims
102 		   to hold */
103 		rc = -1;
104 		goto empty;
105 	}
106 
107 	return x25_addr_ntoa(skb->data, called_addr, calling_addr);
108 
109 empty:
110 	*called_addr->x25_addr = 0;
111 	*calling_addr->x25_addr = 0;
112 
113 	return rc;
114 }
115 
116 
117 int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
118 		  struct x25_address *calling_addr)
119 {
120 	unsigned int called_len, calling_len;
121 	char *called, *calling;
122 	unsigned int i;
123 
124 	called_len  = (*p >> 0) & 0x0F;
125 	calling_len = (*p >> 4) & 0x0F;
126 
127 	called  = called_addr->x25_addr;
128 	calling = calling_addr->x25_addr;
129 	p++;
130 
131 	for (i = 0; i < (called_len + calling_len); i++) {
132 		if (i < called_len) {
133 			if (i % 2 != 0) {
134 				*called++ = ((*p >> 0) & 0x0F) + '0';
135 				p++;
136 			} else {
137 				*called++ = ((*p >> 4) & 0x0F) + '0';
138 			}
139 		} else {
140 			if (i % 2 != 0) {
141 				*calling++ = ((*p >> 0) & 0x0F) + '0';
142 				p++;
143 			} else {
144 				*calling++ = ((*p >> 4) & 0x0F) + '0';
145 			}
146 		}
147 	}
148 
149 	*called = *calling = '\0';
150 
151 	return 1 + (called_len + calling_len + 1) / 2;
152 }
153 
154 int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
155 		  struct x25_address *calling_addr)
156 {
157 	unsigned int called_len, calling_len;
158 	char *called, *calling;
159 	int i;
160 
161 	called  = called_addr->x25_addr;
162 	calling = calling_addr->x25_addr;
163 
164 	called_len  = strlen(called);
165 	calling_len = strlen(calling);
166 
167 	*p++ = (calling_len << 4) | (called_len << 0);
168 
169 	for (i = 0; i < (called_len + calling_len); i++) {
170 		if (i < called_len) {
171 			if (i % 2 != 0) {
172 				*p |= (*called++ - '0') << 0;
173 				p++;
174 			} else {
175 				*p = 0x00;
176 				*p |= (*called++ - '0') << 4;
177 			}
178 		} else {
179 			if (i % 2 != 0) {
180 				*p |= (*calling++ - '0') << 0;
181 				p++;
182 			} else {
183 				*p = 0x00;
184 				*p |= (*calling++ - '0') << 4;
185 			}
186 		}
187 	}
188 
189 	return 1 + (called_len + calling_len + 1) / 2;
190 }
191 
192 /*
193  *	Socket removal during an interrupt is now safe.
194  */
195 static void x25_remove_socket(struct sock *sk)
196 {
197 	write_lock_bh(&x25_list_lock);
198 	sk_del_node_init(sk);
199 	write_unlock_bh(&x25_list_lock);
200 }
201 
202 /*
203  *	Kill all bound sockets on a dropped device.
204  */
205 static void x25_kill_by_device(struct net_device *dev)
206 {
207 	struct sock *s;
208 
209 	write_lock_bh(&x25_list_lock);
210 
211 	sk_for_each(s, &x25_list)
212 		if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
213 			x25_disconnect(s, ENETUNREACH, 0, 0);
214 
215 	write_unlock_bh(&x25_list_lock);
216 }
217 
218 /*
219  *	Handle device status changes.
220  */
221 static int x25_device_event(struct notifier_block *this, unsigned long event,
222 			    void *ptr)
223 {
224 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
225 	struct x25_neigh *nb;
226 
227 	if (!net_eq(dev_net(dev), &init_net))
228 		return NOTIFY_DONE;
229 
230 	if (dev->type == ARPHRD_X25
231 #if IS_ENABLED(CONFIG_LLC)
232 	 || dev->type == ARPHRD_ETHER
233 #endif
234 	 ) {
235 		switch (event) {
236 		case NETDEV_UP:
237 			x25_link_device_up(dev);
238 			break;
239 		case NETDEV_GOING_DOWN:
240 			nb = x25_get_neigh(dev);
241 			if (nb) {
242 				x25_terminate_link(nb);
243 				x25_neigh_put(nb);
244 			}
245 			break;
246 		case NETDEV_DOWN:
247 			x25_kill_by_device(dev);
248 			x25_route_device_down(dev);
249 			x25_link_device_down(dev);
250 			break;
251 		}
252 	}
253 
254 	return NOTIFY_DONE;
255 }
256 
257 /*
258  *	Add a socket to the bound sockets list.
259  */
260 static void x25_insert_socket(struct sock *sk)
261 {
262 	write_lock_bh(&x25_list_lock);
263 	sk_add_node(sk, &x25_list);
264 	write_unlock_bh(&x25_list_lock);
265 }
266 
267 /*
268  *	Find a socket that wants to accept the Call Request we just
269  *	received. Check the full list for an address/cud match.
270  *	If no cuds match return the next_best thing, an address match.
271  *	Note: if a listening socket has cud set it must only get calls
272  *	with matching cud.
273  */
274 static struct sock *x25_find_listener(struct x25_address *addr,
275 					struct sk_buff *skb)
276 {
277 	struct sock *s;
278 	struct sock *next_best;
279 
280 	read_lock_bh(&x25_list_lock);
281 	next_best = NULL;
282 
283 	sk_for_each(s, &x25_list)
284 		if ((!strcmp(addr->x25_addr,
285 			x25_sk(s)->source_addr.x25_addr) ||
286 				!strcmp(x25_sk(s)->source_addr.x25_addr,
287 					null_x25_address.x25_addr)) &&
288 					s->sk_state == TCP_LISTEN) {
289 			/*
290 			 * Found a listening socket, now check the incoming
291 			 * call user data vs this sockets call user data
292 			 */
293 			if (x25_sk(s)->cudmatchlength > 0 &&
294 				skb->len >= x25_sk(s)->cudmatchlength) {
295 				if((memcmp(x25_sk(s)->calluserdata.cuddata,
296 					skb->data,
297 					x25_sk(s)->cudmatchlength)) == 0) {
298 					sock_hold(s);
299 					goto found;
300 				 }
301 			} else
302 				next_best = s;
303 		}
304 	if (next_best) {
305 		s = next_best;
306 		sock_hold(s);
307 		goto found;
308 	}
309 	s = NULL;
310 found:
311 	read_unlock_bh(&x25_list_lock);
312 	return s;
313 }
314 
315 /*
316  *	Find a connected X.25 socket given my LCI and neighbour.
317  */
318 static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
319 {
320 	struct sock *s;
321 
322 	sk_for_each(s, &x25_list)
323 		if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
324 			sock_hold(s);
325 			goto found;
326 		}
327 	s = NULL;
328 found:
329 	return s;
330 }
331 
332 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
333 {
334 	struct sock *s;
335 
336 	read_lock_bh(&x25_list_lock);
337 	s = __x25_find_socket(lci, nb);
338 	read_unlock_bh(&x25_list_lock);
339 	return s;
340 }
341 
342 /*
343  *	Find a unique LCI for a given device.
344  */
345 static unsigned int x25_new_lci(struct x25_neigh *nb)
346 {
347 	unsigned int lci = 1;
348 	struct sock *sk;
349 
350 	while ((sk = x25_find_socket(lci, nb)) != NULL) {
351 		sock_put(sk);
352 		if (++lci == 4096) {
353 			lci = 0;
354 			break;
355 		}
356 		cond_resched();
357 	}
358 
359 	return lci;
360 }
361 
362 /*
363  *	Deferred destroy.
364  */
365 static void __x25_destroy_socket(struct sock *);
366 
367 /*
368  *	handler for deferred kills.
369  */
370 static void x25_destroy_timer(struct timer_list *t)
371 {
372 	struct sock *sk = from_timer(sk, t, sk_timer);
373 
374 	x25_destroy_socket_from_timer(sk);
375 }
376 
377 /*
378  *	This is called from user mode and the timers. Thus it protects itself
379  *	against interrupt users but doesn't worry about being called during
380  *	work. Once it is removed from the queue no interrupt or bottom half
381  *	will touch it and we are (fairly 8-) ) safe.
382  *	Not static as it's used by the timer
383  */
384 static void __x25_destroy_socket(struct sock *sk)
385 {
386 	struct sk_buff *skb;
387 
388 	x25_stop_heartbeat(sk);
389 	x25_stop_timer(sk);
390 
391 	x25_remove_socket(sk);
392 	x25_clear_queues(sk);		/* Flush the queues */
393 
394 	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
395 		if (skb->sk != sk) {		/* A pending connection */
396 			/*
397 			 * Queue the unaccepted socket for death
398 			 */
399 			skb->sk->sk_state = TCP_LISTEN;
400 			sock_set_flag(skb->sk, SOCK_DEAD);
401 			x25_start_heartbeat(skb->sk);
402 			x25_sk(skb->sk)->state = X25_STATE_0;
403 		}
404 
405 		kfree_skb(skb);
406 	}
407 
408 	if (sk_has_allocations(sk)) {
409 		/* Defer: outstanding buffers */
410 		sk->sk_timer.expires  = jiffies + 10 * HZ;
411 		sk->sk_timer.function = x25_destroy_timer;
412 		add_timer(&sk->sk_timer);
413 	} else {
414 		/* drop last reference so sock_put will free */
415 		__sock_put(sk);
416 	}
417 }
418 
419 void x25_destroy_socket_from_timer(struct sock *sk)
420 {
421 	sock_hold(sk);
422 	bh_lock_sock(sk);
423 	__x25_destroy_socket(sk);
424 	bh_unlock_sock(sk);
425 	sock_put(sk);
426 }
427 
428 /*
429  *	Handling for system calls applied via the various interfaces to a
430  *	X.25 socket object.
431  */
432 
433 static int x25_setsockopt(struct socket *sock, int level, int optname,
434 			  char __user *optval, unsigned int optlen)
435 {
436 	int opt;
437 	struct sock *sk = sock->sk;
438 	int rc = -ENOPROTOOPT;
439 
440 	if (level != SOL_X25 || optname != X25_QBITINCL)
441 		goto out;
442 
443 	rc = -EINVAL;
444 	if (optlen < sizeof(int))
445 		goto out;
446 
447 	rc = -EFAULT;
448 	if (get_user(opt, (int __user *)optval))
449 		goto out;
450 
451 	if (opt)
452 		set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
453 	else
454 		clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
455 	rc = 0;
456 out:
457 	return rc;
458 }
459 
460 static int x25_getsockopt(struct socket *sock, int level, int optname,
461 			  char __user *optval, int __user *optlen)
462 {
463 	struct sock *sk = sock->sk;
464 	int val, len, rc = -ENOPROTOOPT;
465 
466 	if (level != SOL_X25 || optname != X25_QBITINCL)
467 		goto out;
468 
469 	rc = -EFAULT;
470 	if (get_user(len, optlen))
471 		goto out;
472 
473 	len = min_t(unsigned int, len, sizeof(int));
474 
475 	rc = -EINVAL;
476 	if (len < 0)
477 		goto out;
478 
479 	rc = -EFAULT;
480 	if (put_user(len, optlen))
481 		goto out;
482 
483 	val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
484 	rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
485 out:
486 	return rc;
487 }
488 
489 static int x25_listen(struct socket *sock, int backlog)
490 {
491 	struct sock *sk = sock->sk;
492 	int rc = -EOPNOTSUPP;
493 
494 	lock_sock(sk);
495 	if (sk->sk_state != TCP_LISTEN) {
496 		memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
497 		sk->sk_max_ack_backlog = backlog;
498 		sk->sk_state           = TCP_LISTEN;
499 		rc = 0;
500 	}
501 	release_sock(sk);
502 
503 	return rc;
504 }
505 
506 static struct proto x25_proto = {
507 	.name	  = "X25",
508 	.owner	  = THIS_MODULE,
509 	.obj_size = sizeof(struct x25_sock),
510 };
511 
512 static struct sock *x25_alloc_socket(struct net *net, int kern)
513 {
514 	struct x25_sock *x25;
515 	struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
516 
517 	if (!sk)
518 		goto out;
519 
520 	sock_init_data(NULL, sk);
521 
522 	x25 = x25_sk(sk);
523 	skb_queue_head_init(&x25->ack_queue);
524 	skb_queue_head_init(&x25->fragment_queue);
525 	skb_queue_head_init(&x25->interrupt_in_queue);
526 	skb_queue_head_init(&x25->interrupt_out_queue);
527 out:
528 	return sk;
529 }
530 
531 static int x25_create(struct net *net, struct socket *sock, int protocol,
532 		      int kern)
533 {
534 	struct sock *sk;
535 	struct x25_sock *x25;
536 	int rc = -EAFNOSUPPORT;
537 
538 	if (!net_eq(net, &init_net))
539 		goto out;
540 
541 	rc = -ESOCKTNOSUPPORT;
542 	if (sock->type != SOCK_SEQPACKET)
543 		goto out;
544 
545 	rc = -EINVAL;
546 	if (protocol)
547 		goto out;
548 
549 	rc = -ENOBUFS;
550 	if ((sk = x25_alloc_socket(net, kern)) == NULL)
551 		goto out;
552 
553 	x25 = x25_sk(sk);
554 
555 	sock_init_data(sock, sk);
556 
557 	x25_init_timers(sk);
558 
559 	sock->ops    = &x25_proto_ops;
560 	sk->sk_protocol = protocol;
561 	sk->sk_backlog_rcv = x25_backlog_rcv;
562 
563 	x25->t21   = sysctl_x25_call_request_timeout;
564 	x25->t22   = sysctl_x25_reset_request_timeout;
565 	x25->t23   = sysctl_x25_clear_request_timeout;
566 	x25->t2    = sysctl_x25_ack_holdback_timeout;
567 	x25->state = X25_STATE_0;
568 	x25->cudmatchlength = 0;
569 	set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);	/* normally no cud  */
570 							/* on call accept   */
571 
572 	x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
573 	x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
574 	x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
575 	x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
576 	x25->facilities.throughput  = 0;	/* by default don't negotiate
577 						   throughput */
578 	x25->facilities.reverse     = X25_DEFAULT_REVERSE;
579 	x25->dte_facilities.calling_len = 0;
580 	x25->dte_facilities.called_len = 0;
581 	memset(x25->dte_facilities.called_ae, '\0',
582 			sizeof(x25->dte_facilities.called_ae));
583 	memset(x25->dte_facilities.calling_ae, '\0',
584 			sizeof(x25->dte_facilities.calling_ae));
585 
586 	rc = 0;
587 out:
588 	return rc;
589 }
590 
591 static struct sock *x25_make_new(struct sock *osk)
592 {
593 	struct sock *sk = NULL;
594 	struct x25_sock *x25, *ox25;
595 
596 	if (osk->sk_type != SOCK_SEQPACKET)
597 		goto out;
598 
599 	if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
600 		goto out;
601 
602 	x25 = x25_sk(sk);
603 
604 	sk->sk_type        = osk->sk_type;
605 	sk->sk_priority    = osk->sk_priority;
606 	sk->sk_protocol    = osk->sk_protocol;
607 	sk->sk_rcvbuf      = osk->sk_rcvbuf;
608 	sk->sk_sndbuf      = osk->sk_sndbuf;
609 	sk->sk_state       = TCP_ESTABLISHED;
610 	sk->sk_backlog_rcv = osk->sk_backlog_rcv;
611 	sock_copy_flags(sk, osk);
612 
613 	ox25 = x25_sk(osk);
614 	x25->t21        = ox25->t21;
615 	x25->t22        = ox25->t22;
616 	x25->t23        = ox25->t23;
617 	x25->t2         = ox25->t2;
618 	x25->flags	= ox25->flags;
619 	x25->facilities = ox25->facilities;
620 	x25->dte_facilities = ox25->dte_facilities;
621 	x25->cudmatchlength = ox25->cudmatchlength;
622 
623 	clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
624 	x25_init_timers(sk);
625 out:
626 	return sk;
627 }
628 
629 static int x25_release(struct socket *sock)
630 {
631 	struct sock *sk = sock->sk;
632 	struct x25_sock *x25;
633 
634 	if (!sk)
635 		return 0;
636 
637 	x25 = x25_sk(sk);
638 
639 	sock_hold(sk);
640 	lock_sock(sk);
641 	switch (x25->state) {
642 
643 		case X25_STATE_0:
644 		case X25_STATE_2:
645 			x25_disconnect(sk, 0, 0, 0);
646 			__x25_destroy_socket(sk);
647 			goto out;
648 
649 		case X25_STATE_1:
650 		case X25_STATE_3:
651 		case X25_STATE_4:
652 			x25_clear_queues(sk);
653 			x25_write_internal(sk, X25_CLEAR_REQUEST);
654 			x25_start_t23timer(sk);
655 			x25->state = X25_STATE_2;
656 			sk->sk_state	= TCP_CLOSE;
657 			sk->sk_shutdown	|= SEND_SHUTDOWN;
658 			sk->sk_state_change(sk);
659 			sock_set_flag(sk, SOCK_DEAD);
660 			sock_set_flag(sk, SOCK_DESTROY);
661 			break;
662 	}
663 
664 	sock_orphan(sk);
665 out:
666 	release_sock(sk);
667 	sock_put(sk);
668 	return 0;
669 }
670 
671 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
672 {
673 	struct sock *sk = sock->sk;
674 	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
675 	int len, i, rc = 0;
676 
677 	if (addr_len != sizeof(struct sockaddr_x25) ||
678 	    addr->sx25_family != AF_X25) {
679 		rc = -EINVAL;
680 		goto out;
681 	}
682 
683 	/* check for the null_x25_address */
684 	if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
685 
686 		len = strlen(addr->sx25_addr.x25_addr);
687 		for (i = 0; i < len; i++) {
688 			if (!isdigit(addr->sx25_addr.x25_addr[i])) {
689 				rc = -EINVAL;
690 				goto out;
691 			}
692 		}
693 	}
694 
695 	lock_sock(sk);
696 	if (sock_flag(sk, SOCK_ZAPPED)) {
697 		x25_sk(sk)->source_addr = addr->sx25_addr;
698 		x25_insert_socket(sk);
699 		sock_reset_flag(sk, SOCK_ZAPPED);
700 	} else {
701 		rc = -EINVAL;
702 	}
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 		read_lock_bh(&x25_list_lock);
820 		x25_neigh_put(x25->neighbour);
821 		x25->neighbour = NULL;
822 		read_unlock_bh(&x25_list_lock);
823 		x25->state = X25_STATE_0;
824 	}
825 out_put_route:
826 	x25_route_put(rt);
827 out:
828 	release_sock(sk);
829 	return rc;
830 }
831 
832 static int x25_wait_for_data(struct sock *sk, long timeout)
833 {
834 	DECLARE_WAITQUEUE(wait, current);
835 	int rc = 0;
836 
837 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
838 	for (;;) {
839 		__set_current_state(TASK_INTERRUPTIBLE);
840 		if (sk->sk_shutdown & RCV_SHUTDOWN)
841 			break;
842 		rc = -ERESTARTSYS;
843 		if (signal_pending(current))
844 			break;
845 		rc = -EAGAIN;
846 		if (!timeout)
847 			break;
848 		rc = 0;
849 		if (skb_queue_empty(&sk->sk_receive_queue)) {
850 			release_sock(sk);
851 			timeout = schedule_timeout(timeout);
852 			lock_sock(sk);
853 		} else
854 			break;
855 	}
856 	__set_current_state(TASK_RUNNING);
857 	remove_wait_queue(sk_sleep(sk), &wait);
858 	return rc;
859 }
860 
861 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
862 		      bool kern)
863 {
864 	struct sock *sk = sock->sk;
865 	struct sock *newsk;
866 	struct sk_buff *skb;
867 	int rc = -EINVAL;
868 
869 	if (!sk)
870 		goto out;
871 
872 	rc = -EOPNOTSUPP;
873 	if (sk->sk_type != SOCK_SEQPACKET)
874 		goto out;
875 
876 	lock_sock(sk);
877 	rc = -EINVAL;
878 	if (sk->sk_state != TCP_LISTEN)
879 		goto out2;
880 
881 	rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
882 	if (rc)
883 		goto out2;
884 	skb = skb_dequeue(&sk->sk_receive_queue);
885 	rc = -EINVAL;
886 	if (!skb->sk)
887 		goto out2;
888 	newsk		 = skb->sk;
889 	sock_graft(newsk, newsock);
890 
891 	/* Now attach up the new socket */
892 	skb->sk = NULL;
893 	kfree_skb(skb);
894 	sk_acceptq_removed(sk);
895 	newsock->state = SS_CONNECTED;
896 	rc = 0;
897 out2:
898 	release_sock(sk);
899 out:
900 	return rc;
901 }
902 
903 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
904 		       int peer)
905 {
906 	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
907 	struct sock *sk = sock->sk;
908 	struct x25_sock *x25 = x25_sk(sk);
909 	int rc = 0;
910 
911 	if (peer) {
912 		if (sk->sk_state != TCP_ESTABLISHED) {
913 			rc = -ENOTCONN;
914 			goto out;
915 		}
916 		sx25->sx25_addr = x25->dest_addr;
917 	} else
918 		sx25->sx25_addr = x25->source_addr;
919 
920 	sx25->sx25_family = AF_X25;
921 	rc = sizeof(*sx25);
922 
923 out:
924 	return rc;
925 }
926 
927 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
928 			unsigned int lci)
929 {
930 	struct sock *sk;
931 	struct sock *make;
932 	struct x25_sock *makex25;
933 	struct x25_address source_addr, dest_addr;
934 	struct x25_facilities facilities;
935 	struct x25_dte_facilities dte_facilities;
936 	int len, addr_len, rc;
937 
938 	/*
939 	 *	Remove the LCI and frame type.
940 	 */
941 	skb_pull(skb, X25_STD_MIN_LEN);
942 
943 	/*
944 	 *	Extract the X.25 addresses and convert them to ASCII strings,
945 	 *	and remove them.
946 	 *
947 	 *	Address block is mandatory in call request packets
948 	 */
949 	addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
950 	if (addr_len <= 0)
951 		goto out_clear_request;
952 	skb_pull(skb, addr_len);
953 
954 	/*
955 	 *	Get the length of the facilities, skip past them for the moment
956 	 *	get the call user data because this is needed to determine
957 	 *	the correct listener
958 	 *
959 	 *	Facilities length is mandatory in call request packets
960 	 */
961 	if (!pskb_may_pull(skb, 1))
962 		goto out_clear_request;
963 	len = skb->data[0] + 1;
964 	if (!pskb_may_pull(skb, len))
965 		goto out_clear_request;
966 	skb_pull(skb,len);
967 
968 	/*
969 	 *	Ensure that the amount of call user data is valid.
970 	 */
971 	if (skb->len > X25_MAX_CUD_LEN)
972 		goto out_clear_request;
973 
974 	/*
975 	 *	Get all the call user data so it can be used in
976 	 *	x25_find_listener and skb_copy_from_linear_data up ahead.
977 	 */
978 	if (!pskb_may_pull(skb, skb->len))
979 		goto out_clear_request;
980 
981 	/*
982 	 *	Find a listener for the particular address/cud pair.
983 	 */
984 	sk = x25_find_listener(&source_addr,skb);
985 	skb_push(skb,len);
986 
987 	if (sk != NULL && sk_acceptq_is_full(sk)) {
988 		goto out_sock_put;
989 	}
990 
991 	/*
992 	 *	We dont have any listeners for this incoming call.
993 	 *	Try forwarding it.
994 	 */
995 	if (sk == NULL) {
996 		skb_push(skb, addr_len + X25_STD_MIN_LEN);
997 		if (sysctl_x25_forward &&
998 				x25_forward_call(&dest_addr, nb, skb, lci) > 0)
999 		{
1000 			/* Call was forwarded, dont process it any more */
1001 			kfree_skb(skb);
1002 			rc = 1;
1003 			goto out;
1004 		} else {
1005 			/* No listeners, can't forward, clear the call */
1006 			goto out_clear_request;
1007 		}
1008 	}
1009 
1010 	/*
1011 	 *	Try to reach a compromise on the requested facilities.
1012 	 */
1013 	len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1014 	if (len == -1)
1015 		goto out_sock_put;
1016 
1017 	/*
1018 	 * current neighbour/link might impose additional limits
1019 	 * on certain facilties
1020 	 */
1021 
1022 	x25_limit_facilities(&facilities, nb);
1023 
1024 	/*
1025 	 *	Try to create a new socket.
1026 	 */
1027 	make = x25_make_new(sk);
1028 	if (!make)
1029 		goto out_sock_put;
1030 
1031 	/*
1032 	 *	Remove the facilities
1033 	 */
1034 	skb_pull(skb, len);
1035 
1036 	skb->sk     = make;
1037 	make->sk_state = TCP_ESTABLISHED;
1038 
1039 	makex25 = x25_sk(make);
1040 	makex25->lci           = lci;
1041 	makex25->dest_addr     = dest_addr;
1042 	makex25->source_addr   = source_addr;
1043 	makex25->neighbour     = nb;
1044 	makex25->facilities    = facilities;
1045 	makex25->dte_facilities= dte_facilities;
1046 	makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1047 	/* ensure no reverse facil on accept */
1048 	makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1049 	/* ensure no calling address extension on accept */
1050 	makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1051 	makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1052 
1053 	/* Normally all calls are accepted immediately */
1054 	if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1055 		x25_write_internal(make, X25_CALL_ACCEPTED);
1056 		makex25->state = X25_STATE_3;
1057 	}
1058 
1059 	/*
1060 	 *	Incoming Call User Data.
1061 	 */
1062 	skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1063 	makex25->calluserdata.cudlength = skb->len;
1064 
1065 	sk_acceptq_added(sk);
1066 
1067 	x25_insert_socket(make);
1068 
1069 	skb_queue_head(&sk->sk_receive_queue, skb);
1070 
1071 	x25_start_heartbeat(make);
1072 
1073 	if (!sock_flag(sk, SOCK_DEAD))
1074 		sk->sk_data_ready(sk);
1075 	rc = 1;
1076 	sock_put(sk);
1077 out:
1078 	return rc;
1079 out_sock_put:
1080 	sock_put(sk);
1081 out_clear_request:
1082 	rc = 0;
1083 	x25_transmit_clear_request(nb, lci, 0x01);
1084 	goto out;
1085 }
1086 
1087 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1088 {
1089 	struct sock *sk = sock->sk;
1090 	struct x25_sock *x25 = x25_sk(sk);
1091 	DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1092 	struct sockaddr_x25 sx25;
1093 	struct sk_buff *skb;
1094 	unsigned char *asmptr;
1095 	int noblock = msg->msg_flags & MSG_DONTWAIT;
1096 	size_t size;
1097 	int qbit = 0, rc = -EINVAL;
1098 
1099 	lock_sock(sk);
1100 	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1101 		goto out;
1102 
1103 	/* we currently don't support segmented records at the user interface */
1104 	if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1105 		goto out;
1106 
1107 	rc = -EADDRNOTAVAIL;
1108 	if (sock_flag(sk, SOCK_ZAPPED))
1109 		goto out;
1110 
1111 	rc = -EPIPE;
1112 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1113 		send_sig(SIGPIPE, current, 0);
1114 		goto out;
1115 	}
1116 
1117 	rc = -ENETUNREACH;
1118 	if (!x25->neighbour)
1119 		goto out;
1120 
1121 	if (usx25) {
1122 		rc = -EINVAL;
1123 		if (msg->msg_namelen < sizeof(sx25))
1124 			goto out;
1125 		memcpy(&sx25, usx25, sizeof(sx25));
1126 		rc = -EISCONN;
1127 		if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1128 			goto out;
1129 		rc = -EINVAL;
1130 		if (sx25.sx25_family != AF_X25)
1131 			goto out;
1132 	} else {
1133 		/*
1134 		 *	FIXME 1003.1g - if the socket is like this because
1135 		 *	it has become closed (not started closed) we ought
1136 		 *	to SIGPIPE, EPIPE;
1137 		 */
1138 		rc = -ENOTCONN;
1139 		if (sk->sk_state != TCP_ESTABLISHED)
1140 			goto out;
1141 
1142 		sx25.sx25_family = AF_X25;
1143 		sx25.sx25_addr   = x25->dest_addr;
1144 	}
1145 
1146 	/* Sanity check the packet size */
1147 	if (len > 65535) {
1148 		rc = -EMSGSIZE;
1149 		goto out;
1150 	}
1151 
1152 	SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1153 
1154 	/* Build a packet */
1155 	SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1156 
1157 	if ((msg->msg_flags & MSG_OOB) && len > 32)
1158 		len = 32;
1159 
1160 	size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1161 
1162 	release_sock(sk);
1163 	skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1164 	lock_sock(sk);
1165 	if (!skb)
1166 		goto out;
1167 	X25_SKB_CB(skb)->flags = msg->msg_flags;
1168 
1169 	skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1170 
1171 	/*
1172 	 *	Put the data on the end
1173 	 */
1174 	SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1175 
1176 	skb_reset_transport_header(skb);
1177 	skb_put(skb, len);
1178 
1179 	rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1180 	if (rc)
1181 		goto out_kfree_skb;
1182 
1183 	/*
1184 	 *	If the Q BIT Include socket option is in force, the first
1185 	 *	byte of the user data is the logical value of the Q Bit.
1186 	 */
1187 	if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1188 		if (!pskb_may_pull(skb, 1))
1189 			goto out_kfree_skb;
1190 
1191 		qbit = skb->data[0];
1192 		skb_pull(skb, 1);
1193 	}
1194 
1195 	/*
1196 	 *	Push down the X.25 header
1197 	 */
1198 	SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1199 
1200 	if (msg->msg_flags & MSG_OOB) {
1201 		if (x25->neighbour->extended) {
1202 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1203 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1204 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1205 			*asmptr++ = X25_INTERRUPT;
1206 		} else {
1207 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1208 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1209 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1210 			*asmptr++ = X25_INTERRUPT;
1211 		}
1212 	} else {
1213 		if (x25->neighbour->extended) {
1214 			/* Build an Extended X.25 header */
1215 			asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1216 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1217 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1218 			*asmptr++ = X25_DATA;
1219 			*asmptr++ = X25_DATA;
1220 		} else {
1221 			/* Build an Standard X.25 header */
1222 			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1223 			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1224 			*asmptr++ = (x25->lci >> 0) & 0xFF;
1225 			*asmptr++ = X25_DATA;
1226 		}
1227 
1228 		if (qbit)
1229 			skb->data[0] |= X25_Q_BIT;
1230 	}
1231 
1232 	SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1233 	SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1234 
1235 	rc = -ENOTCONN;
1236 	if (sk->sk_state != TCP_ESTABLISHED)
1237 		goto out_kfree_skb;
1238 
1239 	if (msg->msg_flags & MSG_OOB)
1240 		skb_queue_tail(&x25->interrupt_out_queue, skb);
1241 	else {
1242 		rc = x25_output(sk, skb);
1243 		len = rc;
1244 		if (rc < 0)
1245 			kfree_skb(skb);
1246 		else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1247 			len++;
1248 	}
1249 
1250 	x25_kick(sk);
1251 	rc = len;
1252 out:
1253 	release_sock(sk);
1254 	return rc;
1255 out_kfree_skb:
1256 	kfree_skb(skb);
1257 	goto out;
1258 }
1259 
1260 
1261 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1262 		       int flags)
1263 {
1264 	struct sock *sk = sock->sk;
1265 	struct x25_sock *x25 = x25_sk(sk);
1266 	DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1267 	size_t copied;
1268 	int qbit, header_len;
1269 	struct sk_buff *skb;
1270 	unsigned char *asmptr;
1271 	int rc = -ENOTCONN;
1272 
1273 	lock_sock(sk);
1274 
1275 	if (x25->neighbour == NULL)
1276 		goto out;
1277 
1278 	header_len = x25->neighbour->extended ?
1279 		X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1280 
1281 	/*
1282 	 * This works for seqpacket too. The receiver has ordered the queue for
1283 	 * us! We do one quick check first though
1284 	 */
1285 	if (sk->sk_state != TCP_ESTABLISHED)
1286 		goto out;
1287 
1288 	if (flags & MSG_OOB) {
1289 		rc = -EINVAL;
1290 		if (sock_flag(sk, SOCK_URGINLINE) ||
1291 		    !skb_peek(&x25->interrupt_in_queue))
1292 			goto out;
1293 
1294 		skb = skb_dequeue(&x25->interrupt_in_queue);
1295 
1296 		if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1297 			goto out_free_dgram;
1298 
1299 		skb_pull(skb, X25_STD_MIN_LEN);
1300 
1301 		/*
1302 		 *	No Q bit information on Interrupt data.
1303 		 */
1304 		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1305 			asmptr  = skb_push(skb, 1);
1306 			*asmptr = 0x00;
1307 		}
1308 
1309 		msg->msg_flags |= MSG_OOB;
1310 	} else {
1311 		/* Now we can treat all alike */
1312 		release_sock(sk);
1313 		skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1314 					flags & MSG_DONTWAIT, &rc);
1315 		lock_sock(sk);
1316 		if (!skb)
1317 			goto out;
1318 
1319 		if (!pskb_may_pull(skb, header_len))
1320 			goto out_free_dgram;
1321 
1322 		qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1323 
1324 		skb_pull(skb, header_len);
1325 
1326 		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1327 			asmptr  = skb_push(skb, 1);
1328 			*asmptr = qbit;
1329 		}
1330 	}
1331 
1332 	skb_reset_transport_header(skb);
1333 	copied = skb->len;
1334 
1335 	if (copied > size) {
1336 		copied = size;
1337 		msg->msg_flags |= MSG_TRUNC;
1338 	}
1339 
1340 	/* Currently, each datagram always contains a complete record */
1341 	msg->msg_flags |= MSG_EOR;
1342 
1343 	rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1344 	if (rc)
1345 		goto out_free_dgram;
1346 
1347 	if (sx25) {
1348 		sx25->sx25_family = AF_X25;
1349 		sx25->sx25_addr   = x25->dest_addr;
1350 		msg->msg_namelen = sizeof(*sx25);
1351 	}
1352 
1353 	x25_check_rbuf(sk);
1354 	rc = copied;
1355 out_free_dgram:
1356 	skb_free_datagram(sk, skb);
1357 out:
1358 	release_sock(sk);
1359 	return rc;
1360 }
1361 
1362 
1363 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1364 {
1365 	struct sock *sk = sock->sk;
1366 	struct x25_sock *x25 = x25_sk(sk);
1367 	void __user *argp = (void __user *)arg;
1368 	int rc;
1369 
1370 	switch (cmd) {
1371 	case TIOCOUTQ: {
1372 		int amount;
1373 
1374 		amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1375 		if (amount < 0)
1376 			amount = 0;
1377 		rc = put_user(amount, (unsigned int __user *)argp);
1378 		break;
1379 	}
1380 
1381 	case TIOCINQ: {
1382 		struct sk_buff *skb;
1383 		int amount = 0;
1384 		/*
1385 		 * These two are safe on a single CPU system as
1386 		 * only user tasks fiddle here
1387 		 */
1388 		lock_sock(sk);
1389 		if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1390 			amount = skb->len;
1391 		release_sock(sk);
1392 		rc = put_user(amount, (unsigned int __user *)argp);
1393 		break;
1394 	}
1395 
1396 	case SIOCGIFADDR:
1397 	case SIOCSIFADDR:
1398 	case SIOCGIFDSTADDR:
1399 	case SIOCSIFDSTADDR:
1400 	case SIOCGIFBRDADDR:
1401 	case SIOCSIFBRDADDR:
1402 	case SIOCGIFNETMASK:
1403 	case SIOCSIFNETMASK:
1404 	case SIOCGIFMETRIC:
1405 	case SIOCSIFMETRIC:
1406 		rc = -EINVAL;
1407 		break;
1408 	case SIOCADDRT:
1409 	case SIOCDELRT:
1410 		rc = -EPERM;
1411 		if (!capable(CAP_NET_ADMIN))
1412 			break;
1413 		rc = x25_route_ioctl(cmd, argp);
1414 		break;
1415 	case SIOCX25GSUBSCRIP:
1416 		rc = x25_subscr_ioctl(cmd, argp);
1417 		break;
1418 	case SIOCX25SSUBSCRIP:
1419 		rc = -EPERM;
1420 		if (!capable(CAP_NET_ADMIN))
1421 			break;
1422 		rc = x25_subscr_ioctl(cmd, argp);
1423 		break;
1424 	case SIOCX25GFACILITIES: {
1425 		lock_sock(sk);
1426 		rc = copy_to_user(argp, &x25->facilities,
1427 				  sizeof(x25->facilities))
1428 			? -EFAULT : 0;
1429 		release_sock(sk);
1430 		break;
1431 	}
1432 
1433 	case SIOCX25SFACILITIES: {
1434 		struct x25_facilities facilities;
1435 		rc = -EFAULT;
1436 		if (copy_from_user(&facilities, argp, sizeof(facilities)))
1437 			break;
1438 		rc = -EINVAL;
1439 		lock_sock(sk);
1440 		if (sk->sk_state != TCP_LISTEN &&
1441 		    sk->sk_state != TCP_CLOSE)
1442 			goto out_fac_release;
1443 		if (facilities.pacsize_in < X25_PS16 ||
1444 		    facilities.pacsize_in > X25_PS4096)
1445 			goto out_fac_release;
1446 		if (facilities.pacsize_out < X25_PS16 ||
1447 		    facilities.pacsize_out > X25_PS4096)
1448 			goto out_fac_release;
1449 		if (facilities.winsize_in < 1 ||
1450 		    facilities.winsize_in > 127)
1451 			goto out_fac_release;
1452 		if (facilities.throughput) {
1453 			int out = facilities.throughput & 0xf0;
1454 			int in  = facilities.throughput & 0x0f;
1455 			if (!out)
1456 				facilities.throughput |=
1457 					X25_DEFAULT_THROUGHPUT << 4;
1458 			else if (out < 0x30 || out > 0xD0)
1459 				goto out_fac_release;
1460 			if (!in)
1461 				facilities.throughput |=
1462 					X25_DEFAULT_THROUGHPUT;
1463 			else if (in < 0x03 || in > 0x0D)
1464 				goto out_fac_release;
1465 		}
1466 		if (facilities.reverse &&
1467 		    (facilities.reverse & 0x81) != 0x81)
1468 			goto out_fac_release;
1469 		x25->facilities = facilities;
1470 		rc = 0;
1471 out_fac_release:
1472 		release_sock(sk);
1473 		break;
1474 	}
1475 
1476 	case SIOCX25GDTEFACILITIES: {
1477 		lock_sock(sk);
1478 		rc = copy_to_user(argp, &x25->dte_facilities,
1479 				  sizeof(x25->dte_facilities));
1480 		release_sock(sk);
1481 		if (rc)
1482 			rc = -EFAULT;
1483 		break;
1484 	}
1485 
1486 	case SIOCX25SDTEFACILITIES: {
1487 		struct x25_dte_facilities dtefacs;
1488 		rc = -EFAULT;
1489 		if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1490 			break;
1491 		rc = -EINVAL;
1492 		lock_sock(sk);
1493 		if (sk->sk_state != TCP_LISTEN &&
1494 		    sk->sk_state != TCP_CLOSE)
1495 			goto out_dtefac_release;
1496 		if (dtefacs.calling_len > X25_MAX_AE_LEN)
1497 			goto out_dtefac_release;
1498 		if (dtefacs.called_len > X25_MAX_AE_LEN)
1499 			goto out_dtefac_release;
1500 		x25->dte_facilities = dtefacs;
1501 		rc = 0;
1502 out_dtefac_release:
1503 		release_sock(sk);
1504 		break;
1505 	}
1506 
1507 	case SIOCX25GCALLUSERDATA: {
1508 		lock_sock(sk);
1509 		rc = copy_to_user(argp, &x25->calluserdata,
1510 				  sizeof(x25->calluserdata))
1511 			? -EFAULT : 0;
1512 		release_sock(sk);
1513 		break;
1514 	}
1515 
1516 	case SIOCX25SCALLUSERDATA: {
1517 		struct x25_calluserdata calluserdata;
1518 
1519 		rc = -EFAULT;
1520 		if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1521 			break;
1522 		rc = -EINVAL;
1523 		if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1524 			break;
1525 		lock_sock(sk);
1526 		x25->calluserdata = calluserdata;
1527 		release_sock(sk);
1528 		rc = 0;
1529 		break;
1530 	}
1531 
1532 	case SIOCX25GCAUSEDIAG: {
1533 		lock_sock(sk);
1534 		rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1535 			? -EFAULT : 0;
1536 		release_sock(sk);
1537 		break;
1538 	}
1539 
1540 	case SIOCX25SCAUSEDIAG: {
1541 		struct x25_causediag causediag;
1542 		rc = -EFAULT;
1543 		if (copy_from_user(&causediag, argp, sizeof(causediag)))
1544 			break;
1545 		lock_sock(sk);
1546 		x25->causediag = causediag;
1547 		release_sock(sk);
1548 		rc = 0;
1549 		break;
1550 
1551 	}
1552 
1553 	case SIOCX25SCUDMATCHLEN: {
1554 		struct x25_subaddr sub_addr;
1555 		rc = -EINVAL;
1556 		lock_sock(sk);
1557 		if(sk->sk_state != TCP_CLOSE)
1558 			goto out_cud_release;
1559 		rc = -EFAULT;
1560 		if (copy_from_user(&sub_addr, argp,
1561 				   sizeof(sub_addr)))
1562 			goto out_cud_release;
1563 		rc = -EINVAL;
1564 		if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1565 			goto out_cud_release;
1566 		x25->cudmatchlength = sub_addr.cudmatchlength;
1567 		rc = 0;
1568 out_cud_release:
1569 		release_sock(sk);
1570 		break;
1571 	}
1572 
1573 	case SIOCX25CALLACCPTAPPRV: {
1574 		rc = -EINVAL;
1575 		lock_sock(sk);
1576 		if (sk->sk_state == TCP_CLOSE) {
1577 			clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1578 			rc = 0;
1579 		}
1580 		release_sock(sk);
1581 		break;
1582 	}
1583 
1584 	case SIOCX25SENDCALLACCPT:  {
1585 		rc = -EINVAL;
1586 		lock_sock(sk);
1587 		if (sk->sk_state != TCP_ESTABLISHED)
1588 			goto out_sendcallaccpt_release;
1589 		/* must call accptapprv above */
1590 		if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1591 			goto out_sendcallaccpt_release;
1592 		x25_write_internal(sk, X25_CALL_ACCEPTED);
1593 		x25->state = X25_STATE_3;
1594 		rc = 0;
1595 out_sendcallaccpt_release:
1596 		release_sock(sk);
1597 		break;
1598 	}
1599 
1600 	default:
1601 		rc = -ENOIOCTLCMD;
1602 		break;
1603 	}
1604 
1605 	return rc;
1606 }
1607 
1608 static const struct net_proto_family x25_family_ops = {
1609 	.family =	AF_X25,
1610 	.create =	x25_create,
1611 	.owner	=	THIS_MODULE,
1612 };
1613 
1614 #ifdef CONFIG_COMPAT
1615 static int compat_x25_subscr_ioctl(unsigned int cmd,
1616 		struct compat_x25_subscrip_struct __user *x25_subscr32)
1617 {
1618 	struct compat_x25_subscrip_struct x25_subscr;
1619 	struct x25_neigh *nb;
1620 	struct net_device *dev;
1621 	int rc = -EINVAL;
1622 
1623 	rc = -EFAULT;
1624 	if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1625 		goto out;
1626 
1627 	rc = -EINVAL;
1628 	dev = x25_dev_get(x25_subscr.device);
1629 	if (dev == NULL)
1630 		goto out;
1631 
1632 	nb = x25_get_neigh(dev);
1633 	if (nb == NULL)
1634 		goto out_dev_put;
1635 
1636 	dev_put(dev);
1637 
1638 	if (cmd == SIOCX25GSUBSCRIP) {
1639 		read_lock_bh(&x25_neigh_list_lock);
1640 		x25_subscr.extended = nb->extended;
1641 		x25_subscr.global_facil_mask = nb->global_facil_mask;
1642 		read_unlock_bh(&x25_neigh_list_lock);
1643 		rc = copy_to_user(x25_subscr32, &x25_subscr,
1644 				sizeof(*x25_subscr32)) ? -EFAULT : 0;
1645 	} else {
1646 		rc = -EINVAL;
1647 		if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1648 			rc = 0;
1649 			write_lock_bh(&x25_neigh_list_lock);
1650 			nb->extended = x25_subscr.extended;
1651 			nb->global_facil_mask = x25_subscr.global_facil_mask;
1652 			write_unlock_bh(&x25_neigh_list_lock);
1653 		}
1654 	}
1655 	x25_neigh_put(nb);
1656 out:
1657 	return rc;
1658 out_dev_put:
1659 	dev_put(dev);
1660 	goto out;
1661 }
1662 
1663 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1664 				unsigned long arg)
1665 {
1666 	void __user *argp = compat_ptr(arg);
1667 	int rc = -ENOIOCTLCMD;
1668 
1669 	switch(cmd) {
1670 	case TIOCOUTQ:
1671 	case TIOCINQ:
1672 		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1673 		break;
1674 	case SIOCGIFADDR:
1675 	case SIOCSIFADDR:
1676 	case SIOCGIFDSTADDR:
1677 	case SIOCSIFDSTADDR:
1678 	case SIOCGIFBRDADDR:
1679 	case SIOCSIFBRDADDR:
1680 	case SIOCGIFNETMASK:
1681 	case SIOCSIFNETMASK:
1682 	case SIOCGIFMETRIC:
1683 	case SIOCSIFMETRIC:
1684 		rc = -EINVAL;
1685 		break;
1686 	case SIOCADDRT:
1687 	case SIOCDELRT:
1688 		rc = -EPERM;
1689 		if (!capable(CAP_NET_ADMIN))
1690 			break;
1691 		rc = x25_route_ioctl(cmd, argp);
1692 		break;
1693 	case SIOCX25GSUBSCRIP:
1694 		rc = compat_x25_subscr_ioctl(cmd, argp);
1695 		break;
1696 	case SIOCX25SSUBSCRIP:
1697 		rc = -EPERM;
1698 		if (!capable(CAP_NET_ADMIN))
1699 			break;
1700 		rc = compat_x25_subscr_ioctl(cmd, argp);
1701 		break;
1702 	case SIOCX25GFACILITIES:
1703 	case SIOCX25SFACILITIES:
1704 	case SIOCX25GDTEFACILITIES:
1705 	case SIOCX25SDTEFACILITIES:
1706 	case SIOCX25GCALLUSERDATA:
1707 	case SIOCX25SCALLUSERDATA:
1708 	case SIOCX25GCAUSEDIAG:
1709 	case SIOCX25SCAUSEDIAG:
1710 	case SIOCX25SCUDMATCHLEN:
1711 	case SIOCX25CALLACCPTAPPRV:
1712 	case SIOCX25SENDCALLACCPT:
1713 		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1714 		break;
1715 	default:
1716 		rc = -ENOIOCTLCMD;
1717 		break;
1718 	}
1719 	return rc;
1720 }
1721 #endif
1722 
1723 static const struct proto_ops x25_proto_ops = {
1724 	.family =	AF_X25,
1725 	.owner =	THIS_MODULE,
1726 	.release =	x25_release,
1727 	.bind =		x25_bind,
1728 	.connect =	x25_connect,
1729 	.socketpair =	sock_no_socketpair,
1730 	.accept =	x25_accept,
1731 	.getname =	x25_getname,
1732 	.poll =		datagram_poll,
1733 	.ioctl =	x25_ioctl,
1734 #ifdef CONFIG_COMPAT
1735 	.compat_ioctl = compat_x25_ioctl,
1736 #endif
1737 	.gettstamp =	sock_gettstamp,
1738 	.listen =	x25_listen,
1739 	.shutdown =	sock_no_shutdown,
1740 	.setsockopt =	x25_setsockopt,
1741 	.getsockopt =	x25_getsockopt,
1742 	.sendmsg =	x25_sendmsg,
1743 	.recvmsg =	x25_recvmsg,
1744 	.mmap =		sock_no_mmap,
1745 	.sendpage =	sock_no_sendpage,
1746 };
1747 
1748 static struct packet_type x25_packet_type __read_mostly = {
1749 	.type =	cpu_to_be16(ETH_P_X25),
1750 	.func =	x25_lapb_receive_frame,
1751 };
1752 
1753 static struct notifier_block x25_dev_notifier = {
1754 	.notifier_call = x25_device_event,
1755 };
1756 
1757 void x25_kill_by_neigh(struct x25_neigh *nb)
1758 {
1759 	struct sock *s;
1760 
1761 	write_lock_bh(&x25_list_lock);
1762 
1763 	sk_for_each(s, &x25_list)
1764 		if (x25_sk(s)->neighbour == nb)
1765 			x25_disconnect(s, ENETUNREACH, 0, 0);
1766 
1767 	write_unlock_bh(&x25_list_lock);
1768 
1769 	/* Remove any related forwards */
1770 	x25_clear_forward_by_dev(nb->dev);
1771 }
1772 
1773 static int __init x25_init(void)
1774 {
1775 	int rc;
1776 
1777 	rc = proto_register(&x25_proto, 0);
1778 	if (rc)
1779 		goto out;
1780 
1781 	rc = sock_register(&x25_family_ops);
1782 	if (rc)
1783 		goto out_proto;
1784 
1785 	dev_add_pack(&x25_packet_type);
1786 
1787 	rc = register_netdevice_notifier(&x25_dev_notifier);
1788 	if (rc)
1789 		goto out_sock;
1790 
1791 	rc = x25_register_sysctl();
1792 	if (rc)
1793 		goto out_dev;
1794 
1795 	rc = x25_proc_init();
1796 	if (rc)
1797 		goto out_sysctl;
1798 
1799 	pr_info("Linux Version 0.2\n");
1800 
1801 out:
1802 	return rc;
1803 out_sysctl:
1804 	x25_unregister_sysctl();
1805 out_dev:
1806 	unregister_netdevice_notifier(&x25_dev_notifier);
1807 out_sock:
1808 	dev_remove_pack(&x25_packet_type);
1809 	sock_unregister(AF_X25);
1810 out_proto:
1811 	proto_unregister(&x25_proto);
1812 	goto out;
1813 }
1814 module_init(x25_init);
1815 
1816 static void __exit x25_exit(void)
1817 {
1818 	x25_proc_exit();
1819 	x25_link_free();
1820 	x25_route_free();
1821 
1822 	x25_unregister_sysctl();
1823 
1824 	unregister_netdevice_notifier(&x25_dev_notifier);
1825 
1826 	dev_remove_pack(&x25_packet_type);
1827 
1828 	sock_unregister(AF_X25);
1829 	proto_unregister(&x25_proto);
1830 }
1831 module_exit(x25_exit);
1832 
1833 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1834 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1835 MODULE_LICENSE("GPL");
1836 MODULE_ALIAS_NETPROTO(PF_X25);
1837