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/signal.h>
  45 #include <linux/timer.h>
  46 #include <linux/string.h>
  47 #include <linux/net.h>
  48 #include <linux/netdevice.h>
  49 #include <linux/if_arp.h>
  50 #include <linux/skbuff.h>
  51 #include <linux/slab.h>
  52 #include <net/sock.h>
  53 #include <net/tcp_states.h>
  54 #include <linux/uaccess.h>
  55 #include <linux/fcntl.h>
  56 #include <linux/termios.h>      /* For TIOCINQ/OUTQ */
  57 #include <linux/notifier.h>
  58 #include <linux/init.h>
  59 #include <linux/compat.h>
  60 #include <linux/ctype.h>
  61
  62 #include <net/x25.h>
  63 #include <net/compat.h>
  64
  65 int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
  66 int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
  67 int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
  68 int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
  69 int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
  70 int sysctl_x25_forward                 = 0;
  71
  72 HLIST_HEAD(x25_list);
  73 DEFINE_RWLOCK(x25_list_lock);
  74
  75 static const struct proto_ops x25_proto_ops;
  76
  77 static struct x25_address null_x25_address = {"               "};
  78
  79 #ifdef CONFIG_COMPAT
  80 struct compat_x25_subscrip_struct {
  81         char device[200-sizeof(compat_ulong_t)];
  82         compat_ulong_t global_facil_mask;
  83         compat_uint_t extended;
  84 };
  85 #endif
  86
  87
  88 int x25_parse_address_block(struct sk_buff *skb,
  89                 struct x25_address *called_addr,
  90                 struct x25_address *calling_addr)
  91 {
  92         unsigned char len;
  93         int needed;
  94         int rc;
  95
  96         if (!pskb_may_pull(skb, 1)) {
  97                 /* packet has no address block */
  98                 rc = 0;
  99                 goto empty;
 100         }
 101
 102         len = *skb->data;
 103         needed = 1 + (len >> 4) + (len & 0x0f);
 104
 105         if (!pskb_may_pull(skb, needed)) {
 106                 /* packet is too short to hold the addresses it claims
 107                    to hold */
 108                 rc = -1;
 109                 goto empty;
 110         }
 111
 112         return x25_addr_ntoa(skb->data, called_addr, calling_addr);
 113
 114 empty:
 115         *called_addr->x25_addr = 0;
 116         *calling_addr->x25_addr = 0;
 117
 118         return rc;
 119 }
 120
 121
 122 int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
 123                   struct x25_address *calling_addr)
 124 {
 125         unsigned int called_len, calling_len;
 126         char *called, *calling;
 127         unsigned int i;
 128
 129         called_len  = (*p >> 0) & 0x0F;
 130         calling_len = (*p >> 4) & 0x0F;
 131
 132         called  = called_addr->x25_addr;
 133         calling = calling_addr->x25_addr;
 134         p++;
 135
 136         for (i = 0; i < (called_len + calling_len); i++) {
 137                 if (i < called_len) {
 138                         if (i % 2 != 0) {
 139                                 *called++ = ((*p >> 0) & 0x0F) + '0';
 140                                 p++;
 141                         } else {
 142                                 *called++ = ((*p >> 4) & 0x0F) + '0';
 143                         }
 144                 } else {
 145                         if (i % 2 != 0) {
 146                                 *calling++ = ((*p >> 0) & 0x0F) + '0';
 147                                 p++;
 148                         } else {
 149                                 *calling++ = ((*p >> 4) & 0x0F) + '0';
 150                         }
 151                 }
 152         }
 153
 154         *called = *calling = '\0';
 155
 156         return 1 + (called_len + calling_len + 1) / 2;
 157 }
 158
 159 int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
 160                   struct x25_address *calling_addr)
 161 {
 162         unsigned int called_len, calling_len;
 163         char *called, *calling;
 164         int i;
 165
 166         called  = called_addr->x25_addr;
 167         calling = calling_addr->x25_addr;
 168
 169         called_len  = strlen(called);
 170         calling_len = strlen(calling);
 171
 172         *p++ = (calling_len << 4) | (called_len << 0);
 173
 174         for (i = 0; i < (called_len + calling_len); i++) {
 175                 if (i < called_len) {
 176                         if (i % 2 != 0) {
 177                                 *p |= (*called++ - '0') << 0;
 178                                 p++;
 179                         } else {
 180                                 *p = 0x00;
 181                                 *p |= (*called++ - '0') << 4;
 182                         }
 183                 } else {
 184                         if (i % 2 != 0) {
 185                                 *p |= (*calling++ - '0') << 0;
 186                                 p++;
 187                         } else {
 188                                 *p = 0x00;
 189                                 *p |= (*calling++ - '0') << 4;
 190                         }
 191                 }
 192         }
 193
 194         return 1 + (called_len + calling_len + 1) / 2;
 195 }
 196
 197 /*
 198  *      Socket removal during an interrupt is now safe.
 199  */
 200 static void x25_remove_socket(struct sock *sk)
 201 {
 202         write_lock_bh(&x25_list_lock);
 203         sk_del_node_init(sk);
 204         write_unlock_bh(&x25_list_lock);
 205 }
 206
 207 /*
 208  *      Kill all bound sockets on a dropped device.
 209  */
 210 static void x25_kill_by_device(struct net_device *dev)
 211 {
 212         struct sock *s;
 213
 214         write_lock_bh(&x25_list_lock);
 215
 216         sk_for_each(s, &x25_list)
 217                 if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
 218                         x25_disconnect(s, ENETUNREACH, 0, 0);
 219
 220         write_unlock_bh(&x25_list_lock);
 221 }
 222
 223 /*
 224  *      Handle device status changes.
 225  */
 226 static int x25_device_event(struct notifier_block *this, unsigned long event,
 227                             void *ptr)
 228 {
 229         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 230         struct x25_neigh *nb;
 231
 232         if (!net_eq(dev_net(dev), &init_net))
 233                 return NOTIFY_DONE;
 234
 235         if (dev->type == ARPHRD_X25
 236 #if IS_ENABLED(CONFIG_LLC)
 237          || dev->type == ARPHRD_ETHER
 238 #endif
 239          ) {
 240                 switch (event) {
 241                 case NETDEV_UP:
 242                         x25_link_device_up(dev);
 243                         break;
 244                 case NETDEV_GOING_DOWN:
 245                         nb = x25_get_neigh(dev);
 246                         if (nb) {
 247                                 x25_terminate_link(nb);
 248                                 x25_neigh_put(nb);
 249                         }
 250                         break;
 251                 case NETDEV_DOWN:
 252                         x25_kill_by_device(dev);
 253                         x25_route_device_down(dev);
 254                         x25_link_device_down(dev);
 255                         break;
 256                 }
 257         }
 258
 259         return NOTIFY_DONE;
 260 }
 261
 262 /*
 263  *      Add a socket to the bound sockets list.
 264  */
 265 static void x25_insert_socket(struct sock *sk)
 266 {
 267         write_lock_bh(&x25_list_lock);
 268         sk_add_node(sk, &x25_list);
 269         write_unlock_bh(&x25_list_lock);
 270 }
 271
 272 /*
 273  *      Find a socket that wants to accept the Call Request we just
 274  *      received. Check the full list for an address/cud match.
 275  *      If no cuds match return the next_best thing, an address match.
 276  *      Note: if a listening socket has cud set it must only get calls
 277  *      with matching cud.
 278  */
 279 static struct sock *x25_find_listener(struct x25_address *addr,
 280                                         struct sk_buff *skb)
 281 {
 282         struct sock *s;
 283         struct sock *next_best;
 284
 285         read_lock_bh(&x25_list_lock);
 286         next_best = NULL;
 287
 288         sk_for_each(s, &x25_list)
 289                 if ((!strcmp(addr->x25_addr,
 290                         x25_sk(s)->source_addr.x25_addr) ||
 291                                 !strcmp(addr->x25_addr,
 292                                         null_x25_address.x25_addr)) &&
 293                                         s->sk_state == TCP_LISTEN) {
 294                         /*
 295                          * Found a listening socket, now check the incoming
 296                          * call user data vs this sockets call user data
 297                          */
 298                         if (x25_sk(s)->cudmatchlength > 0 &&
 299                                 skb->len >= x25_sk(s)->cudmatchlength) {
 300                                 if((memcmp(x25_sk(s)->calluserdata.cuddata,
 301                                         skb->data,
 302                                         x25_sk(s)->cudmatchlength)) == 0) {
 303                                         sock_hold(s);
 304                                         goto found;
 305                                  }
 306                         } else
 307                                 next_best = s;
 308                 }
 309         if (next_best) {
 310                 s = next_best;
 311                 sock_hold(s);
 312                 goto found;
 313         }
 314         s = NULL;
 315 found:
 316         read_unlock_bh(&x25_list_lock);
 317         return s;
 318 }
 319
 320 /*
 321  *      Find a connected X.25 socket given my LCI and neighbour.
 322  */
 323 static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 324 {
 325         struct sock *s;
 326
 327         sk_for_each(s, &x25_list)
 328                 if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
 329                         sock_hold(s);
 330                         goto found;
 331                 }
 332         s = NULL;
 333 found:
 334         return s;
 335 }
 336
 337 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 338 {
 339         struct sock *s;
 340
 341         read_lock_bh(&x25_list_lock);
 342         s = __x25_find_socket(lci, nb);
 343         read_unlock_bh(&x25_list_lock);
 344         return s;
 345 }
 346
 347 /*
 348  *      Find a unique LCI for a given device.
 349  */
 350 static unsigned int x25_new_lci(struct x25_neigh *nb)
 351 {
 352         unsigned int lci = 1;
 353         struct sock *sk;
 354
 355         read_lock_bh(&x25_list_lock);
 356
 357         while ((sk = __x25_find_socket(lci, nb)) != NULL) {
 358                 sock_put(sk);
 359                 if (++lci == 4096) {
 360                         lci = 0;
 361                         break;
 362                 }
 363         }
 364
 365         read_unlock_bh(&x25_list_lock);
 366         return lci;
 367 }
 368
 369 /*
 370  *      Deferred destroy.
 371  */
 372 static void __x25_destroy_socket(struct sock *);
 373
 374 /*
 375  *      handler for deferred kills.
 376  */
 377 static void x25_destroy_timer(unsigned long data)
 378 {
 379         x25_destroy_socket_from_timer((struct sock *)data);
 380 }
 381
 382 /*
 383  *      This is called from user mode and the timers. Thus it protects itself
 384  *      against interrupt users but doesn't worry about being called during
 385  *      work. Once it is removed from the queue no interrupt or bottom half
 386  *      will touch it and we are (fairly 8-) ) safe.
 387  *      Not static as it's used by the timer
 388  */
 389 static void __x25_destroy_socket(struct sock *sk)
 390 {
 391         struct sk_buff *skb;
 392
 393         x25_stop_heartbeat(sk);
 394         x25_stop_timer(sk);
 395
 396         x25_remove_socket(sk);
 397         x25_clear_queues(sk);           /* Flush the queues */
 398
 399         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 400                 if (skb->sk != sk) {            /* A pending connection */
 401                         /*
 402                          * Queue the unaccepted socket for death
 403                          */
 404                         skb->sk->sk_state = TCP_LISTEN;
 405                         sock_set_flag(skb->sk, SOCK_DEAD);
 406                         x25_start_heartbeat(skb->sk);
 407                         x25_sk(skb->sk)->state = X25_STATE_0;
 408                 }
 409
 410                 kfree_skb(skb);
 411         }
 412
 413         if (sk_has_allocations(sk)) {
 414                 /* Defer: outstanding buffers */
 415                 sk->sk_timer.expires  = jiffies + 10 * HZ;
 416                 sk->sk_timer.function = x25_destroy_timer;
 417                 sk->sk_timer.data = (unsigned long)sk;
 418                 add_timer(&sk->sk_timer);
 419         } else {
 420                 /* drop last reference so sock_put will free */
 421                 __sock_put(sk);
 422         }
 423 }
 424
 425 void x25_destroy_socket_from_timer(struct sock *sk)
 426 {
 427         sock_hold(sk);
 428         bh_lock_sock(sk);
 429         __x25_destroy_socket(sk);
 430         bh_unlock_sock(sk);
 431         sock_put(sk);
 432 }
 433
 434 /*
 435  *      Handling for system calls applied via the various interfaces to a
 436  *      X.25 socket object.
 437  */
 438
 439 static int x25_setsockopt(struct socket *sock, int level, int optname,
 440                           char __user *optval, unsigned int optlen)
 441 {
 442         int opt;
 443         struct sock *sk = sock->sk;
 444         int rc = -ENOPROTOOPT;
 445
 446         if (level != SOL_X25 || optname != X25_QBITINCL)
 447                 goto out;
 448
 449         rc = -EINVAL;
 450         if (optlen < sizeof(int))
 451                 goto out;
 452
 453         rc = -EFAULT;
 454         if (get_user(opt, (int __user *)optval))
 455                 goto out;
 456
 457         if (opt)
 458                 set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 459         else
 460                 clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 461         rc = 0;
 462 out:
 463         return rc;
 464 }
 465
 466 static int x25_getsockopt(struct socket *sock, int level, int optname,
 467                           char __user *optval, int __user *optlen)
 468 {
 469         struct sock *sk = sock->sk;
 470         int val, len, rc = -ENOPROTOOPT;
 471
 472         if (level != SOL_X25 || optname != X25_QBITINCL)
 473                 goto out;
 474
 475         rc = -EFAULT;
 476         if (get_user(len, optlen))
 477                 goto out;
 478
 479         len = min_t(unsigned int, len, sizeof(int));
 480
 481         rc = -EINVAL;
 482         if (len < 0)
 483                 goto out;
 484
 485         rc = -EFAULT;
 486         if (put_user(len, optlen))
 487                 goto out;
 488
 489         val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 490         rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
 491 out:
 492         return rc;
 493 }
 494
 495 static int x25_listen(struct socket *sock, int backlog)
 496 {
 497         struct sock *sk = sock->sk;
 498         int rc = -EOPNOTSUPP;
 499
 500         lock_sock(sk);
 501         if (sk->sk_state != TCP_LISTEN) {
 502                 memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 503                 sk->sk_max_ack_backlog = backlog;
 504                 sk->sk_state           = TCP_LISTEN;
 505                 rc = 0;
 506         }
 507         release_sock(sk);
 508
 509         return rc;
 510 }
 511
 512 static struct proto x25_proto = {
 513         .name     = "X25",
 514         .owner    = THIS_MODULE,
 515         .obj_size = sizeof(struct x25_sock),
 516 };
 517
 518 static struct sock *x25_alloc_socket(struct net *net, int kern)
 519 {
 520         struct x25_sock *x25;
 521         struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 522
 523         if (!sk)
 524                 goto out;
 525
 526         sock_init_data(NULL, sk);
 527
 528         x25 = x25_sk(sk);
 529         skb_queue_head_init(&x25->ack_queue);
 530         skb_queue_head_init(&x25->fragment_queue);
 531         skb_queue_head_init(&x25->interrupt_in_queue);
 532         skb_queue_head_init(&x25->interrupt_out_queue);
 533 out:
 534         return sk;
 535 }
 536
 537 static int x25_create(struct net *net, struct socket *sock, int protocol,
 538                       int kern)
 539 {
 540         struct sock *sk;
 541         struct x25_sock *x25;
 542         int rc = -EAFNOSUPPORT;
 543
 544         if (!net_eq(net, &init_net))
 545                 goto out;
 546
 547         rc = -ESOCKTNOSUPPORT;
 548         if (sock->type != SOCK_SEQPACKET)
 549                 goto out;
 550
 551         rc = -EINVAL;
 552         if (protocol)
 553                 goto out;
 554
 555         rc = -ENOBUFS;
 556         if ((sk = x25_alloc_socket(net, kern)) == NULL)
 557                 goto out;
 558
 559         x25 = x25_sk(sk);
 560
 561         sock_init_data(sock, sk);
 562
 563         x25_init_timers(sk);
 564
 565         sock->ops    = &x25_proto_ops;
 566         sk->sk_protocol = protocol;
 567         sk->sk_backlog_rcv = x25_backlog_rcv;
 568
 569         x25->t21   = sysctl_x25_call_request_timeout;
 570         x25->t22   = sysctl_x25_reset_request_timeout;
 571         x25->t23   = sysctl_x25_clear_request_timeout;
 572         x25->t2    = sysctl_x25_ack_holdback_timeout;
 573         x25->state = X25_STATE_0;
 574         x25->cudmatchlength = 0;
 575         set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);     /* normally no cud  */
 576                                                         /* on call accept   */
 577
 578         x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 579         x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 580         x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 581         x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 582         x25->facilities.throughput  = 0;        /* by default don't negotiate
 583                                                    throughput */
 584         x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 585         x25->dte_facilities.calling_len = 0;
 586         x25->dte_facilities.called_len = 0;
 587         memset(x25->dte_facilities.called_ae, '\0',
 588                         sizeof(x25->dte_facilities.called_ae));
 589         memset(x25->dte_facilities.calling_ae, '\0',
 590                         sizeof(x25->dte_facilities.calling_ae));
 591
 592         rc = 0;
 593 out:
 594         return rc;
 595 }
 596
 597 static struct sock *x25_make_new(struct sock *osk)
 598 {
 599         struct sock *sk = NULL;
 600         struct x25_sock *x25, *ox25;
 601
 602         if (osk->sk_type != SOCK_SEQPACKET)
 603                 goto out;
 604
 605         if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 606                 goto out;
 607
 608         x25 = x25_sk(sk);
 609
 610         sk->sk_type        = osk->sk_type;
 611         sk->sk_priority    = osk->sk_priority;
 612         sk->sk_protocol    = osk->sk_protocol;
 613         sk->sk_rcvbuf      = osk->sk_rcvbuf;
 614         sk->sk_sndbuf      = osk->sk_sndbuf;
 615         sk->sk_state       = TCP_ESTABLISHED;
 616         sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 617         sock_copy_flags(sk, osk);
 618
 619         ox25 = x25_sk(osk);
 620         x25->t21        = ox25->t21;
 621         x25->t22        = ox25->t22;
 622         x25->t23        = ox25->t23;
 623         x25->t2         = ox25->t2;
 624         x25->flags      = ox25->flags;
 625         x25->facilities = ox25->facilities;
 626         x25->dte_facilities = ox25->dte_facilities;
 627         x25->cudmatchlength = ox25->cudmatchlength;
 628
 629         clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 630         x25_init_timers(sk);
 631 out:
 632         return sk;
 633 }
 634
 635 static int x25_release(struct socket *sock)
 636 {
 637         struct sock *sk = sock->sk;
 638         struct x25_sock *x25;
 639
 640         if (!sk)
 641                 return 0;
 642
 643         x25 = x25_sk(sk);
 644
 645         sock_hold(sk);
 646         lock_sock(sk);
 647         switch (x25->state) {
 648
 649                 case X25_STATE_0:
 650                 case X25_STATE_2:
 651                         x25_disconnect(sk, 0, 0, 0);
 652                         __x25_destroy_socket(sk);
 653                         goto out;
 654
 655                 case X25_STATE_1:
 656                 case X25_STATE_3:
 657                 case X25_STATE_4:
 658                         x25_clear_queues(sk);
 659                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 660                         x25_start_t23timer(sk);
 661                         x25->state = X25_STATE_2;
 662                         sk->sk_state    = TCP_CLOSE;
 663                         sk->sk_shutdown |= SEND_SHUTDOWN;
 664                         sk->sk_state_change(sk);
 665                         sock_set_flag(sk, SOCK_DEAD);
 666                         sock_set_flag(sk, SOCK_DESTROY);
 667                         break;
 668         }
 669
 670         sock_orphan(sk);
 671 out:
 672         release_sock(sk);
 673         sock_put(sk);
 674         return 0;
 675 }
 676
 677 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 678 {
 679         struct sock *sk = sock->sk;
 680         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 681         int len, i, rc = 0;
 682
 683         if (!sock_flag(sk, SOCK_ZAPPED) ||
 684             addr_len != sizeof(struct sockaddr_x25) ||
 685             addr->sx25_family != AF_X25) {
 686                 rc = -EINVAL;
 687                 goto out;
 688         }
 689
 690         len = strlen(addr->sx25_addr.x25_addr);
 691         for (i = 0; i < len; i++) {
 692                 if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 693                         rc = -EINVAL;
 694                         goto out;
 695                 }
 696         }
 697
 698         lock_sock(sk);
 699         x25_sk(sk)->source_addr = addr->sx25_addr;
 700         x25_insert_socket(sk);
 701         sock_reset_flag(sk, SOCK_ZAPPED);
 702         release_sock(sk);
 703         SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
 704 out:
 705         return rc;
 706 }
 707
 708 static int x25_wait_for_connection_establishment(struct sock *sk)
 709 {
 710         DECLARE_WAITQUEUE(wait, current);
 711         int rc;
 712
 713         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 714         for (;;) {
 715                 __set_current_state(TASK_INTERRUPTIBLE);
 716                 rc = -ERESTARTSYS;
 717                 if (signal_pending(current))
 718                         break;
 719                 rc = sock_error(sk);
 720                 if (rc) {
 721                         sk->sk_socket->state = SS_UNCONNECTED;
 722                         break;
 723                 }
 724                 rc = 0;
 725                 if (sk->sk_state != TCP_ESTABLISHED) {
 726                         release_sock(sk);
 727                         schedule();
 728                         lock_sock(sk);
 729                 } else
 730                         break;
 731         }
 732         __set_current_state(TASK_RUNNING);
 733         remove_wait_queue(sk_sleep(sk), &wait);
 734         return rc;
 735 }
 736
 737 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
 738                        int addr_len, int flags)
 739 {
 740         struct sock *sk = sock->sk;
 741         struct x25_sock *x25 = x25_sk(sk);
 742         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 743         struct x25_route *rt;
 744         int rc = 0;
 745
 746         lock_sock(sk);
 747         if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 748                 sock->state = SS_CONNECTED;
 749                 goto out; /* Connect completed during a ERESTARTSYS event */
 750         }
 751
 752         rc = -ECONNREFUSED;
 753         if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 754                 sock->state = SS_UNCONNECTED;
 755                 goto out;
 756         }
 757
 758         rc = -EISCONN;  /* No reconnect on a seqpacket socket */
 759         if (sk->sk_state == TCP_ESTABLISHED)
 760                 goto out;
 761
 762         sk->sk_state   = TCP_CLOSE;
 763         sock->state = SS_UNCONNECTED;
 764
 765         rc = -EINVAL;
 766         if (addr_len != sizeof(struct sockaddr_x25) ||
 767             addr->sx25_family != AF_X25)
 768                 goto out;
 769
 770         rc = -ENETUNREACH;
 771         rt = x25_get_route(&addr->sx25_addr);
 772         if (!rt)
 773                 goto out;
 774
 775         x25->neighbour = x25_get_neigh(rt->dev);
 776         if (!x25->neighbour)
 777                 goto out_put_route;
 778
 779         x25_limit_facilities(&x25->facilities, x25->neighbour);
 780
 781         x25->lci = x25_new_lci(x25->neighbour);
 782         if (!x25->lci)
 783                 goto out_put_neigh;
 784
 785         rc = -EINVAL;
 786         if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 787                 goto out_put_neigh;
 788
 789         if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 790                 memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 791
 792         x25->dest_addr = addr->sx25_addr;
 793
 794         /* Move to connecting socket, start sending Connect Requests */
 795         sock->state   = SS_CONNECTING;
 796         sk->sk_state  = TCP_SYN_SENT;
 797
 798         x25->state = X25_STATE_1;
 799
 800         x25_write_internal(sk, X25_CALL_REQUEST);
 801
 802         x25_start_heartbeat(sk);
 803         x25_start_t21timer(sk);
 804
 805         /* Now the loop */
 806         rc = -EINPROGRESS;
 807         if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 808                 goto out_put_neigh;
 809
 810         rc = x25_wait_for_connection_establishment(sk);
 811         if (rc)
 812                 goto out_put_neigh;
 813
 814         sock->state = SS_CONNECTED;
 815         rc = 0;
 816 out_put_neigh:
 817         if (rc)
 818                 x25_neigh_put(x25->neighbour);
 819 out_put_route:
 820         x25_route_put(rt);
 821 out:
 822         release_sock(sk);
 823         return rc;
 824 }
 825
 826 static int x25_wait_for_data(struct sock *sk, long timeout)
 827 {
 828         DECLARE_WAITQUEUE(wait, current);
 829         int rc = 0;
 830
 831         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 832         for (;;) {
 833                 __set_current_state(TASK_INTERRUPTIBLE);
 834                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 835                         break;
 836                 rc = -ERESTARTSYS;
 837                 if (signal_pending(current))
 838                         break;
 839                 rc = -EAGAIN;
 840                 if (!timeout)
 841                         break;
 842                 rc = 0;
 843                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 844                         release_sock(sk);
 845                         timeout = schedule_timeout(timeout);
 846                         lock_sock(sk);
 847                 } else
 848                         break;
 849         }
 850         __set_current_state(TASK_RUNNING);
 851         remove_wait_queue(sk_sleep(sk), &wait);
 852         return rc;
 853 }
 854
 855 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 856                       bool kern)
 857 {
 858         struct sock *sk = sock->sk;
 859         struct sock *newsk;
 860         struct sk_buff *skb;
 861         int rc = -EINVAL;
 862
 863         if (!sk)
 864                 goto out;
 865
 866         rc = -EOPNOTSUPP;
 867         if (sk->sk_type != SOCK_SEQPACKET)
 868                 goto out;
 869
 870         lock_sock(sk);
 871         rc = -EINVAL;
 872         if (sk->sk_state != TCP_LISTEN)
 873                 goto out2;
 874
 875         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 876         if (rc)
 877                 goto out2;
 878         skb = skb_dequeue(&sk->sk_receive_queue);
 879         rc = -EINVAL;
 880         if (!skb->sk)
 881                 goto out2;
 882         newsk            = skb->sk;
 883         sock_graft(newsk, newsock);
 884
 885         /* Now attach up the new socket */
 886         skb->sk = NULL;
 887         kfree_skb(skb);
 888         sk->sk_ack_backlog--;
 889         newsock->state = SS_CONNECTED;
 890         rc = 0;
 891 out2:
 892         release_sock(sk);
 893 out:
 894         return rc;
 895 }
 896
 897 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 898                        int *uaddr_len, int peer)
 899 {
 900         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 901         struct sock *sk = sock->sk;
 902         struct x25_sock *x25 = x25_sk(sk);
 903         int rc = 0;
 904
 905         if (peer) {
 906                 if (sk->sk_state != TCP_ESTABLISHED) {
 907                         rc = -ENOTCONN;
 908                         goto out;
 909                 }
 910                 sx25->sx25_addr = x25->dest_addr;
 911         } else
 912                 sx25->sx25_addr = x25->source_addr;
 913
 914         sx25->sx25_family = AF_X25;
 915         *uaddr_len = sizeof(*sx25);
 916
 917 out:
 918         return rc;
 919 }
 920
 921 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 922                         unsigned int lci)
 923 {
 924         struct sock *sk;
 925         struct sock *make;
 926         struct x25_sock *makex25;
 927         struct x25_address source_addr, dest_addr;
 928         struct x25_facilities facilities;
 929         struct x25_dte_facilities dte_facilities;
 930         int len, addr_len, rc;
 931
 932         /*
 933          *      Remove the LCI and frame type.
 934          */
 935         skb_pull(skb, X25_STD_MIN_LEN);
 936
 937         /*
 938          *      Extract the X.25 addresses and convert them to ASCII strings,
 939          *      and remove them.
 940          *
 941          *      Address block is mandatory in call request packets
 942          */
 943         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 944         if (addr_len <= 0)
 945                 goto out_clear_request;
 946         skb_pull(skb, addr_len);
 947
 948         /*
 949          *      Get the length of the facilities, skip past them for the moment
 950          *      get the call user data because this is needed to determine
 951          *      the correct listener
 952          *
 953          *      Facilities length is mandatory in call request packets
 954          */
 955         if (!pskb_may_pull(skb, 1))
 956                 goto out_clear_request;
 957         len = skb->data[0] + 1;
 958         if (!pskb_may_pull(skb, len))
 959                 goto out_clear_request;
 960         skb_pull(skb,len);
 961
 962         /*
 963          *      Ensure that the amount of call user data is valid.
 964          */
 965         if (skb->len > X25_MAX_CUD_LEN)
 966                 goto out_clear_request;
 967
 968         /*
 969          *      Get all the call user data so it can be used in
 970          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 971          */
 972         if (!pskb_may_pull(skb, skb->len))
 973                 goto out_clear_request;
 974
 975         /*
 976          *      Find a listener for the particular address/cud pair.
 977          */
 978         sk = x25_find_listener(&source_addr,skb);
 979         skb_push(skb,len);
 980
 981         if (sk != NULL && sk_acceptq_is_full(sk)) {
 982                 goto out_sock_put;
 983         }
 984
 985         /*
 986          *      We dont have any listeners for this incoming call.
 987          *      Try forwarding it.
 988          */
 989         if (sk == NULL) {
 990                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
 991                 if (sysctl_x25_forward &&
 992                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
 993                 {
 994                         /* Call was forwarded, dont process it any more */
 995                         kfree_skb(skb);
 996                         rc = 1;
 997                         goto out;
 998                 } else {
 999                         /* No listeners, can't forward, clear the call */
1000                         goto out_clear_request;
1001                 }
1002         }
1003
1004         /*
1005          *      Try to reach a compromise on the requested facilities.
1006          */
1007         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1008         if (len == -1)
1009                 goto out_sock_put;
1010
1011         /*
1012          * current neighbour/link might impose additional limits
1013          * on certain facilties
1014          */
1015
1016         x25_limit_facilities(&facilities, nb);
1017
1018         /*
1019          *      Try to create a new socket.
1020          */
1021         make = x25_make_new(sk);
1022         if (!make)
1023                 goto out_sock_put;
1024
1025         /*
1026          *      Remove the facilities
1027          */
1028         skb_pull(skb, len);
1029
1030         skb->sk     = make;
1031         make->sk_state = TCP_ESTABLISHED;
1032
1033         makex25 = x25_sk(make);
1034         makex25->lci           = lci;
1035         makex25->dest_addr     = dest_addr;
1036         makex25->source_addr   = source_addr;
1037         makex25->neighbour     = nb;
1038         makex25->facilities    = facilities;
1039         makex25->dte_facilities= dte_facilities;
1040         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1041         /* ensure no reverse facil on accept */
1042         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1043         /* ensure no calling address extension on accept */
1044         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1045         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1046
1047         /* Normally all calls are accepted immediately */
1048         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1049                 x25_write_internal(make, X25_CALL_ACCEPTED);
1050                 makex25->state = X25_STATE_3;
1051         }
1052
1053         /*
1054          *      Incoming Call User Data.
1055          */
1056         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1057         makex25->calluserdata.cudlength = skb->len;
1058
1059         sk->sk_ack_backlog++;
1060
1061         x25_insert_socket(make);
1062
1063         skb_queue_head(&sk->sk_receive_queue, skb);
1064
1065         x25_start_heartbeat(make);
1066
1067         if (!sock_flag(sk, SOCK_DEAD))
1068                 sk->sk_data_ready(sk);
1069         rc = 1;
1070         sock_put(sk);
1071 out:
1072         return rc;
1073 out_sock_put:
1074         sock_put(sk);
1075 out_clear_request:
1076         rc = 0;
1077         x25_transmit_clear_request(nb, lci, 0x01);
1078         goto out;
1079 }
1080
1081 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1082 {
1083         struct sock *sk = sock->sk;
1084         struct x25_sock *x25 = x25_sk(sk);
1085         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1086         struct sockaddr_x25 sx25;
1087         struct sk_buff *skb;
1088         unsigned char *asmptr;
1089         int noblock = msg->msg_flags & MSG_DONTWAIT;
1090         size_t size;
1091         int qbit = 0, rc = -EINVAL;
1092
1093         lock_sock(sk);
1094         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1095                 goto out;
1096
1097         /* we currently don't support segmented records at the user interface */
1098         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1099                 goto out;
1100
1101         rc = -EADDRNOTAVAIL;
1102         if (sock_flag(sk, SOCK_ZAPPED))
1103                 goto out;
1104
1105         rc = -EPIPE;
1106         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1107                 send_sig(SIGPIPE, current, 0);
1108                 goto out;
1109         }
1110
1111         rc = -ENETUNREACH;
1112         if (!x25->neighbour)
1113                 goto out;
1114
1115         if (usx25) {
1116                 rc = -EINVAL;
1117                 if (msg->msg_namelen < sizeof(sx25))
1118                         goto out;
1119                 memcpy(&sx25, usx25, sizeof(sx25));
1120                 rc = -EISCONN;
1121                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1122                         goto out;
1123                 rc = -EINVAL;
1124                 if (sx25.sx25_family != AF_X25)
1125                         goto out;
1126         } else {
1127                 /*
1128                  *      FIXME 1003.1g - if the socket is like this because
1129                  *      it has become closed (not started closed) we ought
1130                  *      to SIGPIPE, EPIPE;
1131                  */
1132                 rc = -ENOTCONN;
1133                 if (sk->sk_state != TCP_ESTABLISHED)
1134                         goto out;
1135
1136                 sx25.sx25_family = AF_X25;
1137                 sx25.sx25_addr   = x25->dest_addr;
1138         }
1139
1140         /* Sanity check the packet size */
1141         if (len > 65535) {
1142                 rc = -EMSGSIZE;
1143                 goto out;
1144         }
1145
1146         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1147
1148         /* Build a packet */
1149         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1150
1151         if ((msg->msg_flags & MSG_OOB) && len > 32)
1152                 len = 32;
1153
1154         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1155
1156         release_sock(sk);
1157         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1158         lock_sock(sk);
1159         if (!skb)
1160                 goto out;
1161         X25_SKB_CB(skb)->flags = msg->msg_flags;
1162
1163         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1164
1165         /*
1166          *      Put the data on the end
1167          */
1168         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1169
1170         skb_reset_transport_header(skb);
1171         skb_put(skb, len);
1172
1173         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1174         if (rc)
1175                 goto out_kfree_skb;
1176
1177         /*
1178          *      If the Q BIT Include socket option is in force, the first
1179          *      byte of the user data is the logical value of the Q Bit.
1180          */
1181         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1182                 if (!pskb_may_pull(skb, 1))
1183                         goto out_kfree_skb;
1184
1185                 qbit = skb->data[0];
1186                 skb_pull(skb, 1);
1187         }
1188
1189         /*
1190          *      Push down the X.25 header
1191          */
1192         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1193
1194         if (msg->msg_flags & MSG_OOB) {
1195                 if (x25->neighbour->extended) {
1196                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1197                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1198                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1199                         *asmptr++ = X25_INTERRUPT;
1200                 } else {
1201                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1202                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1203                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1204                         *asmptr++ = X25_INTERRUPT;
1205                 }
1206         } else {
1207                 if (x25->neighbour->extended) {
1208                         /* Build an Extended X.25 header */
1209                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1210                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1211                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1212                         *asmptr++ = X25_DATA;
1213                         *asmptr++ = X25_DATA;
1214                 } else {
1215                         /* Build an Standard X.25 header */
1216                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1217                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1218                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1219                         *asmptr++ = X25_DATA;
1220                 }
1221
1222                 if (qbit)
1223                         skb->data[0] |= X25_Q_BIT;
1224         }
1225
1226         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1227         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1228
1229         rc = -ENOTCONN;
1230         if (sk->sk_state != TCP_ESTABLISHED)
1231                 goto out_kfree_skb;
1232
1233         if (msg->msg_flags & MSG_OOB)
1234                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1235         else {
1236                 rc = x25_output(sk, skb);
1237                 len = rc;
1238                 if (rc < 0)
1239                         kfree_skb(skb);
1240                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1241                         len++;
1242         }
1243
1244         x25_kick(sk);
1245         rc = len;
1246 out:
1247         release_sock(sk);
1248         return rc;
1249 out_kfree_skb:
1250         kfree_skb(skb);
1251         goto out;
1252 }
1253
1254
1255 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1256                        int flags)
1257 {
1258         struct sock *sk = sock->sk;
1259         struct x25_sock *x25 = x25_sk(sk);
1260         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1261         size_t copied;
1262         int qbit, header_len;
1263         struct sk_buff *skb;
1264         unsigned char *asmptr;
1265         int rc = -ENOTCONN;
1266
1267         lock_sock(sk);
1268
1269         if (x25->neighbour == NULL)
1270                 goto out;
1271
1272         header_len = x25->neighbour->extended ?
1273                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1274
1275         /*
1276          * This works for seqpacket too. The receiver has ordered the queue for
1277          * us! We do one quick check first though
1278          */
1279         if (sk->sk_state != TCP_ESTABLISHED)
1280                 goto out;
1281
1282         if (flags & MSG_OOB) {
1283                 rc = -EINVAL;
1284                 if (sock_flag(sk, SOCK_URGINLINE) ||
1285                     !skb_peek(&x25->interrupt_in_queue))
1286                         goto out;
1287
1288                 skb = skb_dequeue(&x25->interrupt_in_queue);
1289
1290                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1291                         goto out_free_dgram;
1292
1293                 skb_pull(skb, X25_STD_MIN_LEN);
1294
1295                 /*
1296                  *      No Q bit information on Interrupt data.
1297                  */
1298                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1299                         asmptr  = skb_push(skb, 1);
1300                         *asmptr = 0x00;
1301                 }
1302
1303                 msg->msg_flags |= MSG_OOB;
1304         } else {
1305                 /* Now we can treat all alike */
1306                 release_sock(sk);
1307                 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1308                                         flags & MSG_DONTWAIT, &rc);
1309                 lock_sock(sk);
1310                 if (!skb)
1311                         goto out;
1312
1313                 if (!pskb_may_pull(skb, header_len))
1314                         goto out_free_dgram;
1315
1316                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1317
1318                 skb_pull(skb, header_len);
1319
1320                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1321                         asmptr  = skb_push(skb, 1);
1322                         *asmptr = qbit;
1323                 }
1324         }
1325
1326         skb_reset_transport_header(skb);
1327         copied = skb->len;
1328
1329         if (copied > size) {
1330                 copied = size;
1331                 msg->msg_flags |= MSG_TRUNC;
1332         }
1333
1334         /* Currently, each datagram always contains a complete record */
1335         msg->msg_flags |= MSG_EOR;
1336
1337         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1338         if (rc)
1339                 goto out_free_dgram;
1340
1341         if (sx25) {
1342                 sx25->sx25_family = AF_X25;
1343                 sx25->sx25_addr   = x25->dest_addr;
1344                 msg->msg_namelen = sizeof(*sx25);
1345         }
1346
1347         x25_check_rbuf(sk);
1348         rc = copied;
1349 out_free_dgram:
1350         skb_free_datagram(sk, skb);
1351 out:
1352         release_sock(sk);
1353         return rc;
1354 }
1355
1356
1357 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1358 {
1359         struct sock *sk = sock->sk;
1360         struct x25_sock *x25 = x25_sk(sk);
1361         void __user *argp = (void __user *)arg;
1362         int rc;
1363
1364         switch (cmd) {
1365         case TIOCOUTQ: {
1366                 int amount;
1367
1368                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1369                 if (amount < 0)
1370                         amount = 0;
1371                 rc = put_user(amount, (unsigned int __user *)argp);
1372                 break;
1373         }
1374
1375         case TIOCINQ: {
1376                 struct sk_buff *skb;
1377                 int amount = 0;
1378                 /*
1379                  * These two are safe on a single CPU system as
1380                  * only user tasks fiddle here
1381                  */
1382                 lock_sock(sk);
1383                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1384                         amount = skb->len;
1385                 release_sock(sk);
1386                 rc = put_user(amount, (unsigned int __user *)argp);
1387                 break;
1388         }
1389
1390         case SIOCGSTAMP:
1391                 rc = -EINVAL;
1392                 if (sk)
1393                         rc = sock_get_timestamp(sk,
1394                                                 (struct timeval __user *)argp);
1395                 break;
1396         case SIOCGSTAMPNS:
1397                 rc = -EINVAL;
1398                 if (sk)
1399                         rc = sock_get_timestampns(sk,
1400                                         (struct timespec __user *)argp);
1401                 break;
1402         case SIOCGIFADDR:
1403         case SIOCSIFADDR:
1404         case SIOCGIFDSTADDR:
1405         case SIOCSIFDSTADDR:
1406         case SIOCGIFBRDADDR:
1407         case SIOCSIFBRDADDR:
1408         case SIOCGIFNETMASK:
1409         case SIOCSIFNETMASK:
1410         case SIOCGIFMETRIC:
1411         case SIOCSIFMETRIC:
1412                 rc = -EINVAL;
1413                 break;
1414         case SIOCADDRT:
1415         case SIOCDELRT:
1416                 rc = -EPERM;
1417                 if (!capable(CAP_NET_ADMIN))
1418                         break;
1419                 rc = x25_route_ioctl(cmd, argp);
1420                 break;
1421         case SIOCX25GSUBSCRIP:
1422                 rc = x25_subscr_ioctl(cmd, argp);
1423                 break;
1424         case SIOCX25SSUBSCRIP:
1425                 rc = -EPERM;
1426                 if (!capable(CAP_NET_ADMIN))
1427                         break;
1428                 rc = x25_subscr_ioctl(cmd, argp);
1429                 break;
1430         case SIOCX25GFACILITIES: {
1431                 lock_sock(sk);
1432                 rc = copy_to_user(argp, &x25->facilities,
1433                                   sizeof(x25->facilities))
1434                         ? -EFAULT : 0;
1435                 release_sock(sk);
1436                 break;
1437         }
1438
1439         case SIOCX25SFACILITIES: {
1440                 struct x25_facilities facilities;
1441                 rc = -EFAULT;
1442                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1443                         break;
1444                 rc = -EINVAL;
1445                 lock_sock(sk);
1446                 if (sk->sk_state != TCP_LISTEN &&
1447                     sk->sk_state != TCP_CLOSE)
1448                         goto out_fac_release;
1449                 if (facilities.pacsize_in < X25_PS16 ||
1450                     facilities.pacsize_in > X25_PS4096)
1451                         goto out_fac_release;
1452                 if (facilities.pacsize_out < X25_PS16 ||
1453                     facilities.pacsize_out > X25_PS4096)
1454                         goto out_fac_release;
1455                 if (facilities.winsize_in < 1 ||
1456                     facilities.winsize_in > 127)
1457                         goto out_fac_release;
1458                 if (facilities.throughput) {
1459                         int out = facilities.throughput & 0xf0;
1460                         int in  = facilities.throughput & 0x0f;
1461                         if (!out)
1462                                 facilities.throughput |=
1463                                         X25_DEFAULT_THROUGHPUT << 4;
1464                         else if (out < 0x30 || out > 0xD0)
1465                                 goto out_fac_release;
1466                         if (!in)
1467                                 facilities.throughput |=
1468                                         X25_DEFAULT_THROUGHPUT;
1469                         else if (in < 0x03 || in > 0x0D)
1470                                 goto out_fac_release;
1471                 }
1472                 if (facilities.reverse &&
1473                     (facilities.reverse & 0x81) != 0x81)
1474                         goto out_fac_release;
1475                 x25->facilities = facilities;
1476                 rc = 0;
1477 out_fac_release:
1478                 release_sock(sk);
1479                 break;
1480         }
1481
1482         case SIOCX25GDTEFACILITIES: {
1483                 lock_sock(sk);
1484                 rc = copy_to_user(argp, &x25->dte_facilities,
1485                                   sizeof(x25->dte_facilities));
1486                 release_sock(sk);
1487                 if (rc)
1488                         rc = -EFAULT;
1489                 break;
1490         }
1491
1492         case SIOCX25SDTEFACILITIES: {
1493                 struct x25_dte_facilities dtefacs;
1494                 rc = -EFAULT;
1495                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1496                         break;
1497                 rc = -EINVAL;
1498                 lock_sock(sk);
1499                 if (sk->sk_state != TCP_LISTEN &&
1500                     sk->sk_state != TCP_CLOSE)
1501                         goto out_dtefac_release;
1502                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1503                         goto out_dtefac_release;
1504                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1505                         goto out_dtefac_release;
1506                 x25->dte_facilities = dtefacs;
1507                 rc = 0;
1508 out_dtefac_release:
1509                 release_sock(sk);
1510                 break;
1511         }
1512
1513         case SIOCX25GCALLUSERDATA: {
1514                 lock_sock(sk);
1515                 rc = copy_to_user(argp, &x25->calluserdata,
1516                                   sizeof(x25->calluserdata))
1517                         ? -EFAULT : 0;
1518                 release_sock(sk);
1519                 break;
1520         }
1521
1522         case SIOCX25SCALLUSERDATA: {
1523                 struct x25_calluserdata calluserdata;
1524
1525                 rc = -EFAULT;
1526                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1527                         break;
1528                 rc = -EINVAL;
1529                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1530                         break;
1531                 lock_sock(sk);
1532                 x25->calluserdata = calluserdata;
1533                 release_sock(sk);
1534                 rc = 0;
1535                 break;
1536         }
1537
1538         case SIOCX25GCAUSEDIAG: {
1539                 lock_sock(sk);
1540                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1541                         ? -EFAULT : 0;
1542                 release_sock(sk);
1543                 break;
1544         }
1545
1546         case SIOCX25SCAUSEDIAG: {
1547                 struct x25_causediag causediag;
1548                 rc = -EFAULT;
1549                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1550                         break;
1551                 lock_sock(sk);
1552                 x25->causediag = causediag;
1553                 release_sock(sk);
1554                 rc = 0;
1555                 break;
1556
1557         }
1558
1559         case SIOCX25SCUDMATCHLEN: {
1560                 struct x25_subaddr sub_addr;
1561                 rc = -EINVAL;
1562                 lock_sock(sk);
1563                 if(sk->sk_state != TCP_CLOSE)
1564                         goto out_cud_release;
1565                 rc = -EFAULT;
1566                 if (copy_from_user(&sub_addr, argp,
1567                                    sizeof(sub_addr)))
1568                         goto out_cud_release;
1569                 rc = -EINVAL;
1570                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1571                         goto out_cud_release;
1572                 x25->cudmatchlength = sub_addr.cudmatchlength;
1573                 rc = 0;
1574 out_cud_release:
1575                 release_sock(sk);
1576                 break;
1577         }
1578
1579         case SIOCX25CALLACCPTAPPRV: {
1580                 rc = -EINVAL;
1581                 lock_sock(sk);
1582                 if (sk->sk_state == TCP_CLOSE) {
1583                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1584                         rc = 0;
1585                 }
1586                 release_sock(sk);
1587                 break;
1588         }
1589
1590         case SIOCX25SENDCALLACCPT:  {
1591                 rc = -EINVAL;
1592                 lock_sock(sk);
1593                 if (sk->sk_state != TCP_ESTABLISHED)
1594                         goto out_sendcallaccpt_release;
1595                 /* must call accptapprv above */
1596                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1597                         goto out_sendcallaccpt_release;
1598                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1599                 x25->state = X25_STATE_3;
1600                 rc = 0;
1601 out_sendcallaccpt_release:
1602                 release_sock(sk);
1603                 break;
1604         }
1605
1606         default:
1607                 rc = -ENOIOCTLCMD;
1608                 break;
1609         }
1610
1611         return rc;
1612 }
1613
1614 static const struct net_proto_family x25_family_ops = {
1615         .family =       AF_X25,
1616         .create =       x25_create,
1617         .owner  =       THIS_MODULE,
1618 };
1619
1620 #ifdef CONFIG_COMPAT
1621 static int compat_x25_subscr_ioctl(unsigned int cmd,
1622                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1623 {
1624         struct compat_x25_subscrip_struct x25_subscr;
1625         struct x25_neigh *nb;
1626         struct net_device *dev;
1627         int rc = -EINVAL;
1628
1629         rc = -EFAULT;
1630         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1631                 goto out;
1632
1633         rc = -EINVAL;
1634         dev = x25_dev_get(x25_subscr.device);
1635         if (dev == NULL)
1636                 goto out;
1637
1638         nb = x25_get_neigh(dev);
1639         if (nb == NULL)
1640                 goto out_dev_put;
1641
1642         dev_put(dev);
1643
1644         if (cmd == SIOCX25GSUBSCRIP) {
1645                 read_lock_bh(&x25_neigh_list_lock);
1646                 x25_subscr.extended = nb->extended;
1647                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1648                 read_unlock_bh(&x25_neigh_list_lock);
1649                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1650                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1651         } else {
1652                 rc = -EINVAL;
1653                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1654                         rc = 0;
1655                         write_lock_bh(&x25_neigh_list_lock);
1656                         nb->extended = x25_subscr.extended;
1657                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1658                         write_unlock_bh(&x25_neigh_list_lock);
1659                 }
1660         }
1661         x25_neigh_put(nb);
1662 out:
1663         return rc;
1664 out_dev_put:
1665         dev_put(dev);
1666         goto out;
1667 }
1668
1669 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1670                                 unsigned long arg)
1671 {
1672         void __user *argp = compat_ptr(arg);
1673         struct sock *sk = sock->sk;
1674
1675         int rc = -ENOIOCTLCMD;
1676
1677         switch(cmd) {
1678         case TIOCOUTQ:
1679         case TIOCINQ:
1680                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1681                 break;
1682         case SIOCGSTAMP:
1683                 rc = -EINVAL;
1684                 if (sk)
1685                         rc = compat_sock_get_timestamp(sk,
1686                                         (struct timeval __user*)argp);
1687                 break;
1688         case SIOCGSTAMPNS:
1689                 rc = -EINVAL;
1690                 if (sk)
1691                         rc = compat_sock_get_timestampns(sk,
1692                                         (struct timespec __user*)argp);
1693                 break;
1694         case SIOCGIFADDR:
1695         case SIOCSIFADDR:
1696         case SIOCGIFDSTADDR:
1697         case SIOCSIFDSTADDR:
1698         case SIOCGIFBRDADDR:
1699         case SIOCSIFBRDADDR:
1700         case SIOCGIFNETMASK:
1701         case SIOCSIFNETMASK:
1702         case SIOCGIFMETRIC:
1703         case SIOCSIFMETRIC:
1704                 rc = -EINVAL;
1705                 break;
1706         case SIOCADDRT:
1707         case SIOCDELRT:
1708                 rc = -EPERM;
1709                 if (!capable(CAP_NET_ADMIN))
1710                         break;
1711                 rc = x25_route_ioctl(cmd, argp);
1712                 break;
1713         case SIOCX25GSUBSCRIP:
1714                 rc = compat_x25_subscr_ioctl(cmd, argp);
1715                 break;
1716         case SIOCX25SSUBSCRIP:
1717                 rc = -EPERM;
1718                 if (!capable(CAP_NET_ADMIN))
1719                         break;
1720                 rc = compat_x25_subscr_ioctl(cmd, argp);
1721                 break;
1722         case SIOCX25GFACILITIES:
1723         case SIOCX25SFACILITIES:
1724         case SIOCX25GDTEFACILITIES:
1725         case SIOCX25SDTEFACILITIES:
1726         case SIOCX25GCALLUSERDATA:
1727         case SIOCX25SCALLUSERDATA:
1728         case SIOCX25GCAUSEDIAG:
1729         case SIOCX25SCAUSEDIAG:
1730         case SIOCX25SCUDMATCHLEN:
1731         case SIOCX25CALLACCPTAPPRV:
1732         case SIOCX25SENDCALLACCPT:
1733                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1734                 break;
1735         default:
1736                 rc = -ENOIOCTLCMD;
1737                 break;
1738         }
1739         return rc;
1740 }
1741 #endif
1742
1743 static const struct proto_ops x25_proto_ops = {
1744         .family =       AF_X25,
1745         .owner =        THIS_MODULE,
1746         .release =      x25_release,
1747         .bind =         x25_bind,
1748         .connect =      x25_connect,
1749         .socketpair =   sock_no_socketpair,
1750         .accept =       x25_accept,
1751         .getname =      x25_getname,
1752         .poll =         datagram_poll,
1753         .ioctl =        x25_ioctl,
1754 #ifdef CONFIG_COMPAT
1755         .compat_ioctl = compat_x25_ioctl,
1756 #endif
1757         .listen =       x25_listen,
1758         .shutdown =     sock_no_shutdown,
1759         .setsockopt =   x25_setsockopt,
1760         .getsockopt =   x25_getsockopt,
1761         .sendmsg =      x25_sendmsg,
1762         .recvmsg =      x25_recvmsg,
1763         .mmap =         sock_no_mmap,
1764         .sendpage =     sock_no_sendpage,
1765 };
1766
1767 static struct packet_type x25_packet_type __read_mostly = {
1768         .type = cpu_to_be16(ETH_P_X25),
1769         .func = x25_lapb_receive_frame,
1770 };
1771
1772 static struct notifier_block x25_dev_notifier = {
1773         .notifier_call = x25_device_event,
1774 };
1775
1776 void x25_kill_by_neigh(struct x25_neigh *nb)
1777 {
1778         struct sock *s;
1779
1780         write_lock_bh(&x25_list_lock);
1781
1782         sk_for_each(s, &x25_list)
1783                 if (x25_sk(s)->neighbour == nb)
1784                         x25_disconnect(s, ENETUNREACH, 0, 0);
1785
1786         write_unlock_bh(&x25_list_lock);
1787
1788         /* Remove any related forwards */
1789         x25_clear_forward_by_dev(nb->dev);
1790 }
1791
1792 static int __init x25_init(void)
1793 {
1794         int rc;
1795
1796         rc = proto_register(&x25_proto, 0);
1797         if (rc)
1798                 goto out;
1799
1800         rc = sock_register(&x25_family_ops);
1801         if (rc)
1802                 goto out_proto;
1803
1804         dev_add_pack(&x25_packet_type);
1805
1806         rc = register_netdevice_notifier(&x25_dev_notifier);
1807         if (rc)
1808                 goto out_sock;
1809
1810         rc = x25_register_sysctl();
1811         if (rc)
1812                 goto out_dev;
1813
1814         rc = x25_proc_init();
1815         if (rc)
1816                 goto out_sysctl;
1817
1818         pr_info("Linux Version 0.2\n");
1819
1820 out:
1821         return rc;
1822 out_sysctl:
1823         x25_unregister_sysctl();
1824 out_dev:
1825         unregister_netdevice_notifier(&x25_dev_notifier);
1826 out_sock:
1827         dev_remove_pack(&x25_packet_type);
1828         sock_unregister(AF_X25);
1829 out_proto:
1830         proto_unregister(&x25_proto);
1831         goto out;
1832 }
1833 module_init(x25_init);
1834
1835 static void __exit x25_exit(void)
1836 {
1837         x25_proc_exit();
1838         x25_link_free();
1839         x25_route_free();
1840
1841         x25_unregister_sysctl();
1842
1843         unregister_netdevice_notifier(&x25_dev_notifier);
1844
1845         dev_remove_pack(&x25_packet_type);
1846
1847         sock_unregister(AF_X25);
1848         proto_unregister(&x25_proto);
1849 }
1850 module_exit(x25_exit);
1851
1852 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1853 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1854 MODULE_LICENSE("GPL");
1855 MODULE_ALIAS_NETPROTO(PF_X25);