af_x25.c

   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
  60int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
  61int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
  62int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
  63int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
  64int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
  65int sysctl_x25_forward                 = 0;
  66
  67HLIST_HEAD(x25_list);
  68DEFINE_RWLOCK(x25_list_lock);
  69
  70static const struct proto_ops x25_proto_ops;
  71
  72static const struct x25_address null_x25_address = {"               "};
  73
  74#ifdef CONFIG_COMPAT
  75struct 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
  83int 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
 109empty:
 110	*called_addr->x25_addr = 0;
 111	*calling_addr->x25_addr = 0;
 112
 113	return rc;
 114}
 115
 116
 117int 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
 154int 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 */
 195static void x25_remove_socket(struct sock *sk)
 196{
 197	write_lock_bh(&x25_list_lock);
 198	sk_del_node_init(sk);
 199	write_unlock_bh(&x25_list_lock);
 200}
 201
 202/*
 203 *	Handle device status changes.
 204 */
 205static int x25_device_event(struct notifier_block *this, unsigned long event,
 206			    void *ptr)
 207{
 208	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 209	struct x25_neigh *nb;
 210
 211	if (!net_eq(dev_net(dev), &init_net))
 212		return NOTIFY_DONE;
 213
 214	if (dev->type == ARPHRD_X25) {
 215		switch (event) {
 216		case NETDEV_REGISTER:
 217		case NETDEV_POST_TYPE_CHANGE:
 218			x25_link_device_up(dev);
 219			break;
 220		case NETDEV_DOWN:
 221			nb = x25_get_neigh(dev);
 222			if (nb) {
 223				x25_link_terminated(nb);
 224				x25_neigh_put(nb);
 225			}
 226			x25_route_device_down(dev);
 227			break;
 228		case NETDEV_PRE_TYPE_CHANGE:
 229		case NETDEV_UNREGISTER:
 230			x25_link_device_down(dev);
 231			break;
 232		case NETDEV_CHANGE:
 233			if (!netif_carrier_ok(dev)) {
 234				nb = x25_get_neigh(dev);
 235				if (nb) {
 236					x25_link_terminated(nb);
 237					x25_neigh_put(nb);
 238				}
 239			}
 240			break;
 241		}
 242	}
 243
 244	return NOTIFY_DONE;
 245}
 246
 247/*
 248 *	Add a socket to the bound sockets list.
 249 */
 250static void x25_insert_socket(struct sock *sk)
 251{
 252	write_lock_bh(&x25_list_lock);
 253	sk_add_node(sk, &x25_list);
 254	write_unlock_bh(&x25_list_lock);
 255}
 256
 257/*
 258 *	Find a socket that wants to accept the Call Request we just
 259 *	received. Check the full list for an address/cud match.
 260 *	If no cuds match return the next_best thing, an address match.
 261 *	Note: if a listening socket has cud set it must only get calls
 262 *	with matching cud.
 263 */
 264static struct sock *x25_find_listener(struct x25_address *addr,
 265					struct sk_buff *skb)
 266{
 267	struct sock *s;
 268	struct sock *next_best;
 269
 270	read_lock_bh(&x25_list_lock);
 271	next_best = NULL;
 272
 273	sk_for_each(s, &x25_list)
 274		if ((!strcmp(addr->x25_addr,
 275			x25_sk(s)->source_addr.x25_addr) ||
 276				!strcmp(x25_sk(s)->source_addr.x25_addr,
 277					null_x25_address.x25_addr)) &&
 278					s->sk_state == TCP_LISTEN) {
 279			/*
 280			 * Found a listening socket, now check the incoming
 281			 * call user data vs this sockets call user data
 282			 */
 283			if (x25_sk(s)->cudmatchlength > 0 &&
 284				skb->len >= x25_sk(s)->cudmatchlength) {
 285				if((memcmp(x25_sk(s)->calluserdata.cuddata,
 286					skb->data,
 287					x25_sk(s)->cudmatchlength)) == 0) {
 288					sock_hold(s);
 289					goto found;
 290				 }
 291			} else
 292				next_best = s;
 293		}
 294	if (next_best) {
 295		s = next_best;
 296		sock_hold(s);
 297		goto found;
 298	}
 299	s = NULL;
 300found:
 301	read_unlock_bh(&x25_list_lock);
 302	return s;
 303}
 304
 305/*
 306 *	Find a connected X.25 socket given my LCI and neighbour.
 307 */
 308static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 309{
 310	struct sock *s;
 311
 312	sk_for_each(s, &x25_list)
 313		if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
 314			sock_hold(s);
 315			goto found;
 316		}
 317	s = NULL;
 318found:
 319	return s;
 320}
 321
 322struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 323{
 324	struct sock *s;
 325
 326	read_lock_bh(&x25_list_lock);
 327	s = __x25_find_socket(lci, nb);
 328	read_unlock_bh(&x25_list_lock);
 329	return s;
 330}
 331
 332/*
 333 *	Find a unique LCI for a given device.
 334 */
 335static unsigned int x25_new_lci(struct x25_neigh *nb)
 336{
 337	unsigned int lci = 1;
 338	struct sock *sk;
 339
 340	while ((sk = x25_find_socket(lci, nb)) != NULL) {
 341		sock_put(sk);
 342		if (++lci == 4096) {
 343			lci = 0;
 344			break;
 345		}
 346		cond_resched();
 347	}
 348
 349	return lci;
 350}
 351
 352/*
 353 *	Deferred destroy.
 354 */
 355static void __x25_destroy_socket(struct sock *);
 356
 357/*
 358 *	handler for deferred kills.
 359 */
 360static void x25_destroy_timer(struct timer_list *t)
 361{
 362	struct sock *sk = timer_container_of(sk, t, sk_timer);
 363
 364	x25_destroy_socket_from_timer(sk);
 365}
 366
 367/*
 368 *	This is called from user mode and the timers. Thus it protects itself
 369 *	against interrupting users but doesn't worry about being called during
 370 *	work. Once it is removed from the queue no interrupt or bottom half
 371 *	will touch it and we are (fairly 8-) ) safe.
 372 *	Not static as it's used by the timer
 373 */
 374static void __x25_destroy_socket(struct sock *sk)
 375{
 376	struct sk_buff *skb;
 377
 378	x25_stop_heartbeat(sk);
 379	x25_stop_timer(sk);
 380
 381	x25_remove_socket(sk);
 382	x25_clear_queues(sk);		/* Flush the queues */
 383
 384	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 385		if (skb->sk != sk) {		/* A pending connection */
 386			/*
 387			 * Queue the unaccepted socket for death
 388			 */
 389			skb->sk->sk_state = TCP_LISTEN;
 390			sock_set_flag(skb->sk, SOCK_DEAD);
 391			x25_start_heartbeat(skb->sk);
 392			x25_sk(skb->sk)->state = X25_STATE_0;
 393		}
 394
 395		kfree_skb(skb);
 396	}
 397
 398	if (sk_has_allocations(sk)) {
 399		/* Defer: outstanding buffers */
 400		sk->sk_timer.expires  = jiffies + 10 * HZ;
 401		sk->sk_timer.function = x25_destroy_timer;
 402		add_timer(&sk->sk_timer);
 403	} else {
 404		/* drop last reference so sock_put will free */
 405		__sock_put(sk);
 406	}
 407}
 408
 409void x25_destroy_socket_from_timer(struct sock *sk)
 410{
 411	sock_hold(sk);
 412	bh_lock_sock(sk);
 413	__x25_destroy_socket(sk);
 414	bh_unlock_sock(sk);
 415	sock_put(sk);
 416}
 417
 418/*
 419 *	Handling for system calls applied via the various interfaces to a
 420 *	X.25 socket object.
 421 */
 422
 423static int x25_setsockopt(struct socket *sock, int level, int optname,
 424			  sockptr_t optval, unsigned int optlen)
 425{
 426	int opt;
 427	struct sock *sk = sock->sk;
 428	int rc = -ENOPROTOOPT;
 429
 430	if (level != SOL_X25 || optname != X25_QBITINCL)
 431		goto out;
 432
 433	rc = -EINVAL;
 434	if (optlen < sizeof(int))
 435		goto out;
 436
 437	rc = -EFAULT;
 438	if (copy_from_sockptr(&opt, optval, sizeof(int)))
 439		goto out;
 440
 441	if (opt)
 442		set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 443	else
 444		clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 445	rc = 0;
 446out:
 447	return rc;
 448}
 449
 450static int x25_getsockopt(struct socket *sock, int level, int optname,
 451			  char __user *optval, int __user *optlen)
 452{
 453	struct sock *sk = sock->sk;
 454	int val, len, rc = -ENOPROTOOPT;
 455
 456	if (level != SOL_X25 || optname != X25_QBITINCL)
 457		goto out;
 458
 459	rc = -EFAULT;
 460	if (get_user(len, optlen))
 461		goto out;
 462
 463	rc = -EINVAL;
 464	if (len < 0)
 465		goto out;
 466
 467	len = min_t(unsigned int, len, sizeof(int));
 468
 469	rc = -EFAULT;
 470	if (put_user(len, optlen))
 471		goto out;
 472
 473	val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 474	rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
 475out:
 476	return rc;
 477}
 478
 479static int x25_listen(struct socket *sock, int backlog)
 480{
 481	struct sock *sk = sock->sk;
 482	int rc = -EOPNOTSUPP;
 483
 484	lock_sock(sk);
 485	if (sock->state != SS_UNCONNECTED) {
 486		rc = -EINVAL;
 487		release_sock(sk);
 488		return rc;
 489	}
 490
 491	if (sk->sk_state != TCP_LISTEN) {
 492		memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 493		sk->sk_max_ack_backlog = backlog;
 494		sk->sk_state           = TCP_LISTEN;
 495		rc = 0;
 496	}
 497	release_sock(sk);
 498
 499	return rc;
 500}
 501
 502static struct proto x25_proto = {
 503	.name	  = "X25",
 504	.owner	  = THIS_MODULE,
 505	.obj_size = sizeof(struct x25_sock),
 506};
 507
 508static struct sock *x25_alloc_socket(struct net *net, int kern)
 509{
 510	struct x25_sock *x25;
 511	struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 512
 513	if (!sk)
 514		goto out;
 515
 516	sock_init_data(NULL, sk);
 517
 518	x25 = x25_sk(sk);
 519	skb_queue_head_init(&x25->ack_queue);
 520	skb_queue_head_init(&x25->fragment_queue);
 521	skb_queue_head_init(&x25->interrupt_in_queue);
 522	skb_queue_head_init(&x25->interrupt_out_queue);
 523out:
 524	return sk;
 525}
 526
 527static int x25_create(struct net *net, struct socket *sock, int protocol,
 528		      int kern)
 529{
 530	struct sock *sk;
 531	struct x25_sock *x25;
 532	int rc = -EAFNOSUPPORT;
 533
 534	if (!net_eq(net, &init_net))
 535		goto out;
 536
 537	rc = -ESOCKTNOSUPPORT;
 538	if (sock->type != SOCK_SEQPACKET)
 539		goto out;
 540
 541	rc = -EINVAL;
 542	if (protocol)
 543		goto out;
 544
 545	rc = -ENOMEM;
 546	if ((sk = x25_alloc_socket(net, kern)) == NULL)
 547		goto out;
 548
 549	x25 = x25_sk(sk);
 550
 551	sock_init_data(sock, sk);
 552
 553	x25_init_timers(sk);
 554
 555	sock->ops    = &x25_proto_ops;
 556	sk->sk_protocol = protocol;
 557	sk->sk_backlog_rcv = x25_backlog_rcv;
 558
 559	x25->t21   = sysctl_x25_call_request_timeout;
 560	x25->t22   = sysctl_x25_reset_request_timeout;
 561	x25->t23   = sysctl_x25_clear_request_timeout;
 562	x25->t2    = sysctl_x25_ack_holdback_timeout;
 563	x25->state = X25_STATE_0;
 564	x25->cudmatchlength = 0;
 565	set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);	/* normally no cud  */
 566							/* on call accept   */
 567
 568	x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 569	x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 570	x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 571	x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 572	x25->facilities.throughput  = 0;	/* by default don't negotiate
 573						   throughput */
 574	x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 575	x25->dte_facilities.calling_len = 0;
 576	x25->dte_facilities.called_len = 0;
 577	memset(x25->dte_facilities.called_ae, '\0',
 578			sizeof(x25->dte_facilities.called_ae));
 579	memset(x25->dte_facilities.calling_ae, '\0',
 580			sizeof(x25->dte_facilities.calling_ae));
 581
 582	rc = 0;
 583out:
 584	return rc;
 585}
 586
 587static struct sock *x25_make_new(struct sock *osk)
 588{
 589	struct sock *sk = NULL;
 590	struct x25_sock *x25, *ox25;
 591
 592	if (osk->sk_type != SOCK_SEQPACKET)
 593		goto out;
 594
 595	if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 596		goto out;
 597
 598	x25 = x25_sk(sk);
 599
 600	sk->sk_type        = osk->sk_type;
 601	sk->sk_priority    = READ_ONCE(osk->sk_priority);
 602	sk->sk_protocol    = osk->sk_protocol;
 603	sk->sk_rcvbuf      = osk->sk_rcvbuf;
 604	sk->sk_sndbuf      = osk->sk_sndbuf;
 605	sk->sk_state       = TCP_ESTABLISHED;
 606	sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 607	sock_copy_flags(sk, osk);
 608
 609	ox25 = x25_sk(osk);
 610	x25->t21        = ox25->t21;
 611	x25->t22        = ox25->t22;
 612	x25->t23        = ox25->t23;
 613	x25->t2         = ox25->t2;
 614	x25->flags	= ox25->flags;
 615	x25->facilities = ox25->facilities;
 616	x25->dte_facilities = ox25->dte_facilities;
 617	x25->cudmatchlength = ox25->cudmatchlength;
 618
 619	clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 620	x25_init_timers(sk);
 621out:
 622	return sk;
 623}
 624
 625static int x25_release(struct socket *sock)
 626{
 627	struct sock *sk = sock->sk;
 628	struct x25_sock *x25;
 629
 630	if (!sk)
 631		return 0;
 632
 633	x25 = x25_sk(sk);
 634
 635	sock_hold(sk);
 636	lock_sock(sk);
 637	switch (x25->state) {
 638
 639		case X25_STATE_0:
 640		case X25_STATE_2:
 641			x25_disconnect(sk, 0, 0, 0);
 642			__x25_destroy_socket(sk);
 643			goto out;
 644
 645		case X25_STATE_1:
 646		case X25_STATE_3:
 647		case X25_STATE_4:
 648			x25_clear_queues(sk);
 649			x25_write_internal(sk, X25_CLEAR_REQUEST);
 650			x25_start_t23timer(sk);
 651			x25->state = X25_STATE_2;
 652			sk->sk_state	= TCP_CLOSE;
 653			sk->sk_shutdown	|= SEND_SHUTDOWN;
 654			sk->sk_state_change(sk);
 655			sock_set_flag(sk, SOCK_DEAD);
 656			sock_set_flag(sk, SOCK_DESTROY);
 657			break;
 658
 659		case X25_STATE_5:
 660			x25_write_internal(sk, X25_CLEAR_REQUEST);
 661			x25_disconnect(sk, 0, 0, 0);
 662			__x25_destroy_socket(sk);
 663			goto out;
 664	}
 665
 666	sock_orphan(sk);
 667out:
 668	release_sock(sk);
 669	sock_put(sk);
 670	return 0;
 671}
 672
 673static int x25_bind(struct socket *sock, struct sockaddr_unsized *uaddr, int addr_len)
 674{
 675	struct sock *sk = sock->sk;
 676	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 677	int len, i, rc = 0;
 678
 679	if (addr_len != sizeof(struct sockaddr_x25) ||
 680	    addr->sx25_family != AF_X25 ||
 681	    strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) {
 682		rc = -EINVAL;
 683		goto out;
 684	}
 685
 686	/* check for the null_x25_address */
 687	if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
 688
 689		len = strlen(addr->sx25_addr.x25_addr);
 690		for (i = 0; i < len; i++) {
 691			if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 692				rc = -EINVAL;
 693				goto out;
 694			}
 695		}
 696	}
 697
 698	lock_sock(sk);
 699	if (sock_flag(sk, SOCK_ZAPPED)) {
 700		x25_sk(sk)->source_addr = addr->sx25_addr;
 701		x25_insert_socket(sk);
 702		sock_reset_flag(sk, SOCK_ZAPPED);
 703	} else {
 704		rc = -EINVAL;
 705	}
 706	release_sock(sk);
 707	net_dbg_ratelimited("x25_bind: socket is bound\n");
 708out:
 709	return rc;
 710}
 711
 712static int x25_wait_for_connection_establishment(struct sock *sk)
 713{
 714	DECLARE_WAITQUEUE(wait, current);
 715	int rc;
 716
 717	add_wait_queue_exclusive(sk_sleep(sk), &wait);
 718	for (;;) {
 719		__set_current_state(TASK_INTERRUPTIBLE);
 720		rc = -ERESTARTSYS;
 721		if (signal_pending(current))
 722			break;
 723		rc = sock_error(sk);
 724		if (rc) {
 725			sk->sk_socket->state = SS_UNCONNECTED;
 726			break;
 727		}
 728		rc = -ENOTCONN;
 729		if (sk->sk_state == TCP_CLOSE) {
 730			sk->sk_socket->state = SS_UNCONNECTED;
 731			break;
 732		}
 733		rc = 0;
 734		if (sk->sk_state != TCP_ESTABLISHED) {
 735			release_sock(sk);
 736			schedule();
 737			lock_sock(sk);
 738		} else
 739			break;
 740	}
 741	__set_current_state(TASK_RUNNING);
 742	remove_wait_queue(sk_sleep(sk), &wait);
 743	return rc;
 744}
 745
 746static int x25_connect(struct socket *sock, struct sockaddr_unsized *uaddr,
 747		       int addr_len, int flags)
 748{
 749	struct sock *sk = sock->sk;
 750	struct x25_sock *x25 = x25_sk(sk);
 751	struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 752	struct x25_route *rt;
 753	int rc = 0;
 754
 755	lock_sock(sk);
 756	if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 757		sock->state = SS_CONNECTED;
 758		goto out; /* Connect completed during a ERESTARTSYS event */
 759	}
 760
 761	rc = -ECONNREFUSED;
 762	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 763		sock->state = SS_UNCONNECTED;
 764		goto out;
 765	}
 766
 767	rc = -EISCONN;	/* No reconnect on a seqpacket socket */
 768	if (sk->sk_state == TCP_ESTABLISHED)
 769		goto out;
 770
 771	rc = -EALREADY;	/* Do nothing if call is already in progress */
 772	if (sk->sk_state == TCP_SYN_SENT)
 773		goto out;
 774
 775	sk->sk_state   = TCP_CLOSE;
 776	sock->state = SS_UNCONNECTED;
 777
 778	rc = -EINVAL;
 779	if (addr_len != sizeof(struct sockaddr_x25) ||
 780	    addr->sx25_family != AF_X25 ||
 781	    strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN)
 782		goto out;
 783
 784	rc = -ENETUNREACH;
 785	rt = x25_get_route(&addr->sx25_addr);
 786	if (!rt)
 787		goto out;
 788
 789	x25->neighbour = x25_get_neigh(rt->dev);
 790	if (!x25->neighbour)
 791		goto out_put_route;
 792
 793	x25_limit_facilities(&x25->facilities, x25->neighbour);
 794
 795	x25->lci = x25_new_lci(x25->neighbour);
 796	if (!x25->lci)
 797		goto out_put_neigh;
 798
 799	rc = -EINVAL;
 800	if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 801		goto out_put_neigh;
 802
 803	if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 804		memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 805
 806	x25->dest_addr = addr->sx25_addr;
 807
 808	/* Move to connecting socket, start sending Connect Requests */
 809	sock->state   = SS_CONNECTING;
 810	sk->sk_state  = TCP_SYN_SENT;
 811
 812	x25->state = X25_STATE_1;
 813
 814	x25_write_internal(sk, X25_CALL_REQUEST);
 815
 816	x25_start_heartbeat(sk);
 817	x25_start_t21timer(sk);
 818
 819	/* Now the loop */
 820	rc = -EINPROGRESS;
 821	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 822		goto out;
 823
 824	rc = x25_wait_for_connection_establishment(sk);
 825	if (rc)
 826		goto out_put_neigh;
 827
 828	sock->state = SS_CONNECTED;
 829	rc = 0;
 830out_put_neigh:
 831	if (rc && x25->neighbour) {
 832		read_lock_bh(&x25_list_lock);
 833		x25_neigh_put(x25->neighbour);
 834		x25->neighbour = NULL;
 835		read_unlock_bh(&x25_list_lock);
 836		x25->state = X25_STATE_0;
 837	}
 838out_put_route:
 839	x25_route_put(rt);
 840out:
 841	release_sock(sk);
 842	return rc;
 843}
 844
 845static int x25_wait_for_data(struct sock *sk, long timeout)
 846{
 847	DECLARE_WAITQUEUE(wait, current);
 848	int rc = 0;
 849
 850	add_wait_queue_exclusive(sk_sleep(sk), &wait);
 851	for (;;) {
 852		__set_current_state(TASK_INTERRUPTIBLE);
 853		if (sk->sk_shutdown & RCV_SHUTDOWN)
 854			break;
 855		rc = -ERESTARTSYS;
 856		if (signal_pending(current))
 857			break;
 858		rc = -EAGAIN;
 859		if (!timeout)
 860			break;
 861		rc = 0;
 862		if (skb_queue_empty(&sk->sk_receive_queue)) {
 863			release_sock(sk);
 864			timeout = schedule_timeout(timeout);
 865			lock_sock(sk);
 866		} else
 867			break;
 868	}
 869	__set_current_state(TASK_RUNNING);
 870	remove_wait_queue(sk_sleep(sk), &wait);
 871	return rc;
 872}
 873
 874static int x25_accept(struct socket *sock, struct socket *newsock,
 875		      struct proto_accept_arg *arg)
 876{
 877	struct sock *sk = sock->sk;
 878	struct sock *newsk;
 879	struct sk_buff *skb;
 880	int rc = -EINVAL;
 881
 882	if (!sk)
 883		goto out;
 884
 885	rc = -EOPNOTSUPP;
 886	if (sk->sk_type != SOCK_SEQPACKET)
 887		goto out;
 888
 889	lock_sock(sk);
 890	rc = -EINVAL;
 891	if (sk->sk_state != TCP_LISTEN)
 892		goto out2;
 893
 894	rc = x25_wait_for_data(sk, READ_ONCE(sk->sk_rcvtimeo));
 895	if (rc)
 896		goto out2;
 897	skb = skb_dequeue(&sk->sk_receive_queue);
 898	rc = -EINVAL;
 899	if (!skb->sk)
 900		goto out2;
 901	newsk		 = skb->sk;
 902	sock_graft(newsk, newsock);
 903
 904	/* Now attach up the new socket */
 905	skb->sk = NULL;
 906	kfree_skb(skb);
 907	sk_acceptq_removed(sk);
 908	newsock->state = SS_CONNECTED;
 909	rc = 0;
 910out2:
 911	release_sock(sk);
 912out:
 913	return rc;
 914}
 915
 916static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 917		       int peer)
 918{
 919	struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 920	struct sock *sk = sock->sk;
 921	struct x25_sock *x25 = x25_sk(sk);
 922	int rc = 0;
 923
 924	if (peer) {
 925		if (sk->sk_state != TCP_ESTABLISHED) {
 926			rc = -ENOTCONN;
 927			goto out;
 928		}
 929		sx25->sx25_addr = x25->dest_addr;
 930	} else
 931		sx25->sx25_addr = x25->source_addr;
 932
 933	sx25->sx25_family = AF_X25;
 934	rc = sizeof(*sx25);
 935
 936out:
 937	return rc;
 938}
 939
 940int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 941			unsigned int lci)
 942{
 943	struct sock *sk;
 944	struct sock *make;
 945	struct x25_sock *makex25;
 946	struct x25_address source_addr, dest_addr;
 947	struct x25_facilities facilities;
 948	struct x25_dte_facilities dte_facilities;
 949	int len, addr_len, rc;
 950
 951	/*
 952	 *	Remove the LCI and frame type.
 953	 */
 954	skb_pull(skb, X25_STD_MIN_LEN);
 955
 956	/*
 957	 *	Extract the X.25 addresses and convert them to ASCII strings,
 958	 *	and remove them.
 959	 *
 960	 *	Address block is mandatory in call request packets
 961	 */
 962	addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 963	if (addr_len <= 0)
 964		goto out_clear_request;
 965	skb_pull(skb, addr_len);
 966
 967	/*
 968	 *	Get the length of the facilities, skip past them for the moment
 969	 *	get the call user data because this is needed to determine
 970	 *	the correct listener
 971	 *
 972	 *	Facilities length is mandatory in call request packets
 973	 */
 974	if (!pskb_may_pull(skb, 1))
 975		goto out_clear_request;
 976	len = skb->data[0] + 1;
 977	if (!pskb_may_pull(skb, len))
 978		goto out_clear_request;
 979	skb_pull(skb,len);
 980
 981	/*
 982	 *	Ensure that the amount of call user data is valid.
 983	 */
 984	if (skb->len > X25_MAX_CUD_LEN)
 985		goto out_clear_request;
 986
 987	/*
 988	 *	Get all the call user data so it can be used in
 989	 *	x25_find_listener and skb_copy_from_linear_data up ahead.
 990	 */
 991	if (!pskb_may_pull(skb, skb->len))
 992		goto out_clear_request;
 993
 994	/*
 995	 *	Find a listener for the particular address/cud pair.
 996	 */
 997	sk = x25_find_listener(&source_addr,skb);
 998	skb_push(skb,len);
 999
1000	if (sk != NULL && sk_acceptq_is_full(sk)) {
1001		goto out_sock_put;
1002	}
1003
1004	/*
1005	 *	We dont have any listeners for this incoming call.
1006	 *	Try forwarding it.
1007	 */
1008	if (sk == NULL) {
1009		skb_push(skb, addr_len + X25_STD_MIN_LEN);
1010		if (sysctl_x25_forward &&
1011				x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1012		{
1013			/* Call was forwarded, dont process it any more */
1014			kfree_skb(skb);
1015			rc = 1;
1016			goto out;
1017		} else {
1018			/* No listeners, can't forward, clear the call */
1019			goto out_clear_request;
1020		}
1021	}
1022
1023	/*
1024	 *	Try to reach a compromise on the requested facilities.
1025	 */
1026	len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1027	if (len == -1)
1028		goto out_sock_put;
1029
1030	/*
1031	 * current neighbour/link might impose additional limits
1032	 * on certain facilities
1033	 */
1034
1035	x25_limit_facilities(&facilities, nb);
1036
1037	/*
1038	 *	Try to create a new socket.
1039	 */
1040	make = x25_make_new(sk);
1041	if (!make)
1042		goto out_sock_put;
1043
1044	/*
1045	 *	Remove the facilities
1046	 */
1047	skb_pull(skb, len);
1048
1049	skb->sk     = make;
1050	make->sk_state = TCP_ESTABLISHED;
1051
1052	makex25 = x25_sk(make);
1053	makex25->lci           = lci;
1054	makex25->dest_addr     = dest_addr;
1055	makex25->source_addr   = source_addr;
1056	x25_neigh_hold(nb);
1057	makex25->neighbour     = nb;
1058	makex25->facilities    = facilities;
1059	makex25->dte_facilities= dte_facilities;
1060	makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1061	/* ensure no reverse facil on accept */
1062	makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1063	/* ensure no calling address extension on accept */
1064	makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1065	makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1066
1067	/* Normally all calls are accepted immediately */
1068	if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1069		x25_write_internal(make, X25_CALL_ACCEPTED);
1070		makex25->state = X25_STATE_3;
1071	} else {
1072		makex25->state = X25_STATE_5;
1073	}
1074
1075	/*
1076	 *	Incoming Call User Data.
1077	 */
1078	skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1079	makex25->calluserdata.cudlength = skb->len;
1080
1081	sk_acceptq_added(sk);
1082
1083	x25_insert_socket(make);
1084
1085	skb_queue_head(&sk->sk_receive_queue, skb);
1086
1087	x25_start_heartbeat(make);
1088
1089	if (!sock_flag(sk, SOCK_DEAD))
1090		sk->sk_data_ready(sk);
1091	rc = 1;
1092	sock_put(sk);
1093out:
1094	return rc;
1095out_sock_put:
1096	sock_put(sk);
1097out_clear_request:
1098	rc = 0;
1099	x25_transmit_clear_request(nb, lci, 0x01);
1100	goto out;
1101}
1102
1103static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1104{
1105	struct sock *sk = sock->sk;
1106	struct x25_sock *x25 = x25_sk(sk);
1107	DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1108	struct sockaddr_x25 sx25;
1109	struct sk_buff *skb;
1110	unsigned char *asmptr;
1111	int noblock = msg->msg_flags & MSG_DONTWAIT;
1112	size_t size;
1113	int qbit = 0, rc = -EINVAL;
1114
1115	lock_sock(sk);
1116	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1117		goto out;
1118
1119	/* we currently don't support segmented records at the user interface */
1120	if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1121		goto out;
1122
1123	rc = -EADDRNOTAVAIL;
1124	if (sock_flag(sk, SOCK_ZAPPED))
1125		goto out;
1126
1127	rc = -EPIPE;
1128	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1129		send_sig(SIGPIPE, current, 0);
1130		goto out;
1131	}
1132
1133	rc = -ENETUNREACH;
1134	if (!x25->neighbour)
1135		goto out;
1136
1137	if (usx25) {
1138		rc = -EINVAL;
1139		if (msg->msg_namelen < sizeof(sx25))
1140			goto out;
1141		memcpy(&sx25, usx25, sizeof(sx25));
1142		rc = -EISCONN;
1143		if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1144			goto out;
1145		rc = -EINVAL;
1146		if (sx25.sx25_family != AF_X25)
1147			goto out;
1148	} else {
1149		/*
1150		 *	FIXME 1003.1g - if the socket is like this because
1151		 *	it has become closed (not started closed) we ought
1152		 *	to SIGPIPE, EPIPE;
1153		 */
1154		rc = -ENOTCONN;
1155		if (sk->sk_state != TCP_ESTABLISHED)
1156			goto out;
1157
1158		sx25.sx25_family = AF_X25;
1159		sx25.sx25_addr   = x25->dest_addr;
1160	}
1161
1162	/* Sanity check the packet size */
1163	if (len > 65535) {
1164		rc = -EMSGSIZE;
1165		goto out;
1166	}
1167
1168	net_dbg_ratelimited("x25_sendmsg: sendto: Addresses built.\n");
1169
1170	/* Build a packet */
1171	net_dbg_ratelimited("x25_sendmsg: sendto: building packet.\n");
1172
1173	if ((msg->msg_flags & MSG_OOB) && len > 32)
1174		len = 32;
1175
1176	size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1177
1178	release_sock(sk);
1179	skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1180	lock_sock(sk);
1181	if (!skb)
1182		goto out;
1183	X25_SKB_CB(skb)->flags = msg->msg_flags;
1184
1185	skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1186
1187	/*
1188	 *	Put the data on the end
1189	 */
1190	net_dbg_ratelimited("x25_sendmsg: Copying user data\n");
1191
1192	skb_reset_transport_header(skb);
1193	skb_put(skb, len);
1194
1195	rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1196	if (rc)
1197		goto out_kfree_skb;
1198
1199	/*
1200	 *	If the Q BIT Include socket option is in force, the first
1201	 *	byte of the user data is the logical value of the Q Bit.
1202	 */
1203	if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1204		if (!pskb_may_pull(skb, 1))
1205			goto out_kfree_skb;
1206
1207		qbit = skb->data[0];
1208		skb_pull(skb, 1);
1209	}
1210
1211	/*
1212	 *	Push down the X.25 header
1213	 */
1214	net_dbg_ratelimited("x25_sendmsg: Building X.25 Header.\n");
1215
1216	if (msg->msg_flags & MSG_OOB) {
1217		if (x25->neighbour->extended) {
1218			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1219			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1220			*asmptr++ = (x25->lci >> 0) & 0xFF;
1221			*asmptr++ = X25_INTERRUPT;
1222		} else {
1223			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1224			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1225			*asmptr++ = (x25->lci >> 0) & 0xFF;
1226			*asmptr++ = X25_INTERRUPT;
1227		}
1228	} else {
1229		if (x25->neighbour->extended) {
1230			/* Build an Extended X.25 header */
1231			asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1232			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1233			*asmptr++ = (x25->lci >> 0) & 0xFF;
1234			*asmptr++ = X25_DATA;
1235			*asmptr++ = X25_DATA;
1236		} else {
1237			/* Build an Standard X.25 header */
1238			asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1239			*asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1240			*asmptr++ = (x25->lci >> 0) & 0xFF;
1241			*asmptr++ = X25_DATA;
1242		}
1243
1244		if (qbit)
1245			skb->data[0] |= X25_Q_BIT;
1246	}
1247
1248	net_dbg_ratelimited("x25_sendmsg: Built header.\n");
1249	net_dbg_ratelimited("x25_sendmsg: Transmitting buffer\n");
1250
1251	rc = -ENOTCONN;
1252	if (sk->sk_state != TCP_ESTABLISHED)
1253		goto out_kfree_skb;
1254
1255	if (msg->msg_flags & MSG_OOB)
1256		skb_queue_tail(&x25->interrupt_out_queue, skb);
1257	else {
1258		rc = x25_output(sk, skb);
1259		len = rc;
1260		if (rc < 0)
1261			kfree_skb(skb);
1262		else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1263			len++;
1264	}
1265
1266	x25_kick(sk);
1267	rc = len;
1268out:
1269	release_sock(sk);
1270	return rc;
1271out_kfree_skb:
1272	kfree_skb(skb);
1273	goto out;
1274}
1275
1276
1277static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1278		       int flags)
1279{
1280	struct sock *sk = sock->sk;
1281	struct x25_sock *x25 = x25_sk(sk);
1282	DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1283	size_t copied;
1284	int qbit, header_len;
1285	struct sk_buff *skb;
1286	unsigned char *asmptr;
1287	int rc = -ENOTCONN;
1288
1289	lock_sock(sk);
1290
1291	if (x25->neighbour == NULL)
1292		goto out;
1293
1294	header_len = x25->neighbour->extended ?
1295		X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1296
1297	/*
1298	 * This works for seqpacket too. The receiver has ordered the queue for
1299	 * us! We do one quick check first though
1300	 */
1301	if (sk->sk_state != TCP_ESTABLISHED)
1302		goto out;
1303
1304	if (flags & MSG_OOB) {
1305		rc = -EINVAL;
1306		if (sock_flag(sk, SOCK_URGINLINE) ||
1307		    !skb_peek(&x25->interrupt_in_queue))
1308			goto out;
1309
1310		skb = skb_dequeue(&x25->interrupt_in_queue);
1311
1312		if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1313			goto out_free_dgram;
1314
1315		skb_pull(skb, X25_STD_MIN_LEN);
1316
1317		/*
1318		 *	No Q bit information on Interrupt data.
1319		 */
1320		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1321			asmptr  = skb_push(skb, 1);
1322			*asmptr = 0x00;
1323		}
1324
1325		msg->msg_flags |= MSG_OOB;
1326	} else {
1327		/* Now we can treat all alike */
1328		release_sock(sk);
1329		skb = skb_recv_datagram(sk, flags, &rc);
1330		lock_sock(sk);
1331		if (!skb)
1332			goto out;
1333
1334		if (!pskb_may_pull(skb, header_len))
1335			goto out_free_dgram;
1336
1337		qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1338
1339		skb_pull(skb, header_len);
1340
1341		if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1342			asmptr  = skb_push(skb, 1);
1343			*asmptr = qbit;
1344		}
1345	}
1346
1347	skb_reset_transport_header(skb);
1348	copied = skb->len;
1349
1350	if (copied > size) {
1351		copied = size;
1352		msg->msg_flags |= MSG_TRUNC;
1353	}
1354
1355	/* Currently, each datagram always contains a complete record */
1356	msg->msg_flags |= MSG_EOR;
1357
1358	rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1359	if (rc)
1360		goto out_free_dgram;
1361
1362	if (sx25) {
1363		sx25->sx25_family = AF_X25;
1364		sx25->sx25_addr   = x25->dest_addr;
1365		msg->msg_namelen = sizeof(*sx25);
1366	}
1367
1368	x25_check_rbuf(sk);
1369	rc = copied;
1370out_free_dgram:
1371	skb_free_datagram(sk, skb);
1372out:
1373	release_sock(sk);
1374	return rc;
1375}
1376
1377
1378static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1379{
1380	struct sock *sk = sock->sk;
1381	struct x25_sock *x25 = x25_sk(sk);
1382	void __user *argp = (void __user *)arg;
1383	int rc;
1384
1385	switch (cmd) {
1386	case TIOCOUTQ: {
1387		int amount;
1388
1389		amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1390		if (amount < 0)
1391			amount = 0;
1392		rc = put_user(amount, (unsigned int __user *)argp);
1393		break;
1394	}
1395
1396	case TIOCINQ: {
1397		struct sk_buff *skb;
1398		int amount = 0;
1399		/*
1400		 * These two are safe on a single CPU system as
1401		 * only user tasks fiddle here
1402		 */
1403		lock_sock(sk);
1404		if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1405			amount = skb->len;
1406		release_sock(sk);
1407		rc = put_user(amount, (unsigned int __user *)argp);
1408		break;
1409	}
1410
1411	case SIOCGIFADDR:
1412	case SIOCSIFADDR:
1413	case SIOCGIFDSTADDR:
1414	case SIOCSIFDSTADDR:
1415	case SIOCGIFBRDADDR:
1416	case SIOCSIFBRDADDR:
1417	case SIOCGIFNETMASK:
1418	case SIOCSIFNETMASK:
1419	case SIOCGIFMETRIC:
1420	case SIOCSIFMETRIC:
1421		rc = -EINVAL;
1422		break;
1423	case SIOCADDRT:
1424	case SIOCDELRT:
1425		rc = -EPERM;
1426		if (!capable(CAP_NET_ADMIN))
1427			break;
1428		rc = x25_route_ioctl(cmd, argp);
1429		break;
1430	case SIOCX25GSUBSCRIP:
1431		rc = x25_subscr_ioctl(cmd, argp);
1432		break;
1433	case SIOCX25SSUBSCRIP:
1434		rc = -EPERM;
1435		if (!capable(CAP_NET_ADMIN))
1436			break;
1437		rc = x25_subscr_ioctl(cmd, argp);
1438		break;
1439	case SIOCX25GFACILITIES: {
1440		lock_sock(sk);
1441		rc = copy_to_user(argp, &x25->facilities,
1442				  sizeof(x25->facilities))
1443			? -EFAULT : 0;
1444		release_sock(sk);
1445		break;
1446	}
1447
1448	case SIOCX25SFACILITIES: {
1449		struct x25_facilities facilities;
1450		rc = -EFAULT;
1451		if (copy_from_user(&facilities, argp, sizeof(facilities)))
1452			break;
1453		rc = -EINVAL;
1454		lock_sock(sk);
1455		if (sk->sk_state != TCP_LISTEN &&
1456		    sk->sk_state != TCP_CLOSE)
1457			goto out_fac_release;
1458		if (facilities.pacsize_in < X25_PS16 ||
1459		    facilities.pacsize_in > X25_PS4096)
1460			goto out_fac_release;
1461		if (facilities.pacsize_out < X25_PS16 ||
1462		    facilities.pacsize_out > X25_PS4096)
1463			goto out_fac_release;
1464		if (facilities.winsize_in < 1 ||
1465		    facilities.winsize_in > 127)
1466			goto out_fac_release;
1467		if (facilities.throughput) {
1468			int out = facilities.throughput & 0xf0;
1469			int in  = facilities.throughput & 0x0f;
1470			if (!out)
1471				facilities.throughput |=
1472					X25_DEFAULT_THROUGHPUT << 4;
1473			else if (out < 0x30 || out > 0xD0)
1474				goto out_fac_release;
1475			if (!in)
1476				facilities.throughput |=
1477					X25_DEFAULT_THROUGHPUT;
1478			else if (in < 0x03 || in > 0x0D)
1479				goto out_fac_release;
1480		}
1481		if (facilities.reverse &&
1482		    (facilities.reverse & 0x81) != 0x81)
1483			goto out_fac_release;
1484		x25->facilities = facilities;
1485		rc = 0;
1486out_fac_release:
1487		release_sock(sk);
1488		break;
1489	}
1490
1491	case SIOCX25GDTEFACILITIES: {
1492		lock_sock(sk);
1493		rc = copy_to_user(argp, &x25->dte_facilities,
1494				  sizeof(x25->dte_facilities));
1495		release_sock(sk);
1496		if (rc)
1497			rc = -EFAULT;
1498		break;
1499	}
1500
1501	case SIOCX25SDTEFACILITIES: {
1502		struct x25_dte_facilities dtefacs;
1503		rc = -EFAULT;
1504		if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1505			break;
1506		rc = -EINVAL;
1507		lock_sock(sk);
1508		if (sk->sk_state != TCP_LISTEN &&
1509		    sk->sk_state != TCP_CLOSE)
1510			goto out_dtefac_release;
1511		if (dtefacs.calling_len > X25_MAX_AE_LEN)
1512			goto out_dtefac_release;
1513		if (dtefacs.called_len > X25_MAX_AE_LEN)
1514			goto out_dtefac_release;
1515		x25->dte_facilities = dtefacs;
1516		rc = 0;
1517out_dtefac_release:
1518		release_sock(sk);
1519		break;
1520	}
1521
1522	case SIOCX25GCALLUSERDATA: {
1523		lock_sock(sk);
1524		rc = copy_to_user(argp, &x25->calluserdata,
1525				  sizeof(x25->calluserdata))
1526			? -EFAULT : 0;
1527		release_sock(sk);
1528		break;
1529	}
1530
1531	case SIOCX25SCALLUSERDATA: {
1532		struct x25_calluserdata calluserdata;
1533
1534		rc = -EFAULT;
1535		if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1536			break;
1537		rc = -EINVAL;
1538		if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1539			break;
1540		lock_sock(sk);
1541		x25->calluserdata = calluserdata;
1542		release_sock(sk);
1543		rc = 0;
1544		break;
1545	}
1546
1547	case SIOCX25GCAUSEDIAG: {
1548		lock_sock(sk);
1549		rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1550			? -EFAULT : 0;
1551		release_sock(sk);
1552		break;
1553	}
1554
1555	case SIOCX25SCAUSEDIAG: {
1556		struct x25_causediag causediag;
1557		rc = -EFAULT;
1558		if (copy_from_user(&causediag, argp, sizeof(causediag)))
1559			break;
1560		lock_sock(sk);
1561		x25->causediag = causediag;
1562		release_sock(sk);
1563		rc = 0;
1564		break;
1565
1566	}
1567
1568	case SIOCX25SCUDMATCHLEN: {
1569		struct x25_subaddr sub_addr;
1570		rc = -EINVAL;
1571		lock_sock(sk);
1572		if(sk->sk_state != TCP_CLOSE)
1573			goto out_cud_release;
1574		rc = -EFAULT;
1575		if (copy_from_user(&sub_addr, argp,
1576				   sizeof(sub_addr)))
1577			goto out_cud_release;
1578		rc = -EINVAL;
1579		if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1580			goto out_cud_release;
1581		x25->cudmatchlength = sub_addr.cudmatchlength;
1582		rc = 0;
1583out_cud_release:
1584		release_sock(sk);
1585		break;
1586	}
1587
1588	case SIOCX25CALLACCPTAPPRV: {
1589		rc = -EINVAL;
1590		lock_sock(sk);
1591		if (sk->sk_state == TCP_CLOSE) {
1592			clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1593			rc = 0;
1594		}
1595		release_sock(sk);
1596		break;
1597	}
1598
1599	case SIOCX25SENDCALLACCPT:  {
1600		rc = -EINVAL;
1601		lock_sock(sk);
1602		if (sk->sk_state != TCP_ESTABLISHED)
1603			goto out_sendcallaccpt_release;
1604		/* must call accptapprv above */
1605		if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1606			goto out_sendcallaccpt_release;
1607		x25_write_internal(sk, X25_CALL_ACCEPTED);
1608		x25->state = X25_STATE_3;
1609		rc = 0;
1610out_sendcallaccpt_release:
1611		release_sock(sk);
1612		break;
1613	}
1614
1615	default:
1616		rc = -ENOIOCTLCMD;
1617		break;
1618	}
1619
1620	return rc;
1621}
1622
1623static const struct net_proto_family x25_family_ops = {
1624	.family =	AF_X25,
1625	.create =	x25_create,
1626	.owner	=	THIS_MODULE,
1627};
1628
1629#ifdef CONFIG_COMPAT
1630static int compat_x25_subscr_ioctl(unsigned int cmd,
1631		struct compat_x25_subscrip_struct __user *x25_subscr32)
1632{
1633	struct compat_x25_subscrip_struct x25_subscr;
1634	struct x25_neigh *nb;
1635	struct net_device *dev;
1636	int rc = -EINVAL;
1637
1638	rc = -EFAULT;
1639	if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1640		goto out;
1641
1642	rc = -EINVAL;
1643	dev = x25_dev_get(x25_subscr.device);
1644	if (dev == NULL)
1645		goto out;
1646
1647	nb = x25_get_neigh(dev);
1648	if (nb == NULL)
1649		goto out_dev_put;
1650
1651	dev_put(dev);
1652
1653	if (cmd == SIOCX25GSUBSCRIP) {
1654		read_lock_bh(&x25_neigh_list_lock);
1655		x25_subscr.extended = nb->extended;
1656		x25_subscr.global_facil_mask = nb->global_facil_mask;
1657		read_unlock_bh(&x25_neigh_list_lock);
1658		rc = copy_to_user(x25_subscr32, &x25_subscr,
1659				sizeof(*x25_subscr32)) ? -EFAULT : 0;
1660	} else {
1661		rc = -EINVAL;
1662		if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1663			rc = 0;
1664			write_lock_bh(&x25_neigh_list_lock);
1665			nb->extended = x25_subscr.extended;
1666			nb->global_facil_mask = x25_subscr.global_facil_mask;
1667			write_unlock_bh(&x25_neigh_list_lock);
1668		}
1669	}
1670	x25_neigh_put(nb);
1671out:
1672	return rc;
1673out_dev_put:
1674	dev_put(dev);
1675	goto out;
1676}
1677
1678static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1679				unsigned long arg)
1680{
1681	void __user *argp = compat_ptr(arg);
1682	int rc = -ENOIOCTLCMD;
1683
1684	switch(cmd) {
1685	case TIOCOUTQ:
1686	case TIOCINQ:
1687		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1688		break;
1689	case SIOCGIFADDR:
1690	case SIOCSIFADDR:
1691	case SIOCGIFDSTADDR:
1692	case SIOCSIFDSTADDR:
1693	case SIOCGIFBRDADDR:
1694	case SIOCSIFBRDADDR:
1695	case SIOCGIFNETMASK:
1696	case SIOCSIFNETMASK:
1697	case SIOCGIFMETRIC:
1698	case SIOCSIFMETRIC:
1699		rc = -EINVAL;
1700		break;
1701	case SIOCADDRT:
1702	case SIOCDELRT:
1703		rc = -EPERM;
1704		if (!capable(CAP_NET_ADMIN))
1705			break;
1706		rc = x25_route_ioctl(cmd, argp);
1707		break;
1708	case SIOCX25GSUBSCRIP:
1709		rc = compat_x25_subscr_ioctl(cmd, argp);
1710		break;
1711	case SIOCX25SSUBSCRIP:
1712		rc = -EPERM;
1713		if (!capable(CAP_NET_ADMIN))
1714			break;
1715		rc = compat_x25_subscr_ioctl(cmd, argp);
1716		break;
1717	case SIOCX25GFACILITIES:
1718	case SIOCX25SFACILITIES:
1719	case SIOCX25GDTEFACILITIES:
1720	case SIOCX25SDTEFACILITIES:
1721	case SIOCX25GCALLUSERDATA:
1722	case SIOCX25SCALLUSERDATA:
1723	case SIOCX25GCAUSEDIAG:
1724	case SIOCX25SCAUSEDIAG:
1725	case SIOCX25SCUDMATCHLEN:
1726	case SIOCX25CALLACCPTAPPRV:
1727	case SIOCX25SENDCALLACCPT:
1728		rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1729		break;
1730	default:
1731		rc = -ENOIOCTLCMD;
1732		break;
1733	}
1734	return rc;
1735}
1736#endif
1737
1738static const struct proto_ops x25_proto_ops = {
1739	.family =	AF_X25,
1740	.owner =	THIS_MODULE,
1741	.release =	x25_release,
1742	.bind =		x25_bind,
1743	.connect =	x25_connect,
1744	.socketpair =	sock_no_socketpair,
1745	.accept =	x25_accept,
1746	.getname =	x25_getname,
1747	.poll =		datagram_poll,
1748	.ioctl =	x25_ioctl,
1749#ifdef CONFIG_COMPAT
1750	.compat_ioctl = compat_x25_ioctl,
1751#endif
1752	.gettstamp =	sock_gettstamp,
1753	.listen =	x25_listen,
1754	.shutdown =	sock_no_shutdown,
1755	.setsockopt =	x25_setsockopt,
1756	.getsockopt =	x25_getsockopt,
1757	.sendmsg =	x25_sendmsg,
1758	.recvmsg =	x25_recvmsg,
1759	.mmap =		sock_no_mmap,
1760};
1761
1762static struct packet_type x25_packet_type __read_mostly = {
1763	.type =	cpu_to_be16(ETH_P_X25),
1764	.func =	x25_lapb_receive_frame,
1765};
1766
1767static struct notifier_block x25_dev_notifier = {
1768	.notifier_call = x25_device_event,
1769};
1770
1771void x25_kill_by_neigh(struct x25_neigh *nb)
1772{
1773	struct sock *s;
1774
1775	write_lock_bh(&x25_list_lock);
1776
1777	sk_for_each(s, &x25_list) {
1778		if (x25_sk(s)->neighbour == nb) {
1779			write_unlock_bh(&x25_list_lock);
1780			lock_sock(s);
1781			x25_disconnect(s, ENETUNREACH, 0, 0);
1782			release_sock(s);
1783			write_lock_bh(&x25_list_lock);
1784		}
1785	}
1786	write_unlock_bh(&x25_list_lock);
1787
1788	/* Remove any related forwards */
1789	x25_clear_forward_by_dev(nb->dev);
1790}
1791
1792static 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
1820out:
1821	return rc;
1822out_sysctl:
1823	x25_unregister_sysctl();
1824out_dev:
1825	unregister_netdevice_notifier(&x25_dev_notifier);
1826out_sock:
1827	dev_remove_pack(&x25_packet_type);
1828	sock_unregister(AF_X25);
1829out_proto:
1830	proto_unregister(&x25_proto);
1831	goto out;
1832}
1833module_init(x25_init);
1834
1835static 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}
1850module_exit(x25_exit);
1851
1852MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1853MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1854MODULE_LICENSE("GPL");
1855MODULE_ALIAS_NETPROTO(PF_X25);