net/x25/af_x25.c

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