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 const 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(struct timer_list *t)
 378 {
 379         struct sock *sk = from_timer(sk, t, sk_timer);
 380
 381         x25_destroy_socket_from_timer(sk);
 382 }
 383
 384 /*
 385  *      This is called from user mode and the timers. Thus it protects itself
 386  *      against interrupt users but doesn't worry about being called during
 387  *      work. Once it is removed from the queue no interrupt or bottom half
 388  *      will touch it and we are (fairly 8-) ) safe.
 389  *      Not static as it's used by the timer
 390  */
 391 static void __x25_destroy_socket(struct sock *sk)
 392 {
 393         struct sk_buff *skb;
 394
 395         x25_stop_heartbeat(sk);
 396         x25_stop_timer(sk);
 397
 398         x25_remove_socket(sk);
 399         x25_clear_queues(sk);           /* Flush the queues */
 400
 401         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 402                 if (skb->sk != sk) {            /* A pending connection */
 403                         /*
 404                          * Queue the unaccepted socket for death
 405                          */
 406                         skb->sk->sk_state = TCP_LISTEN;
 407                         sock_set_flag(skb->sk, SOCK_DEAD);
 408                         x25_start_heartbeat(skb->sk);
 409                         x25_sk(skb->sk)->state = X25_STATE_0;
 410                 }
 411
 412                 kfree_skb(skb);
 413         }
 414
 415         if (sk_has_allocations(sk)) {
 416                 /* Defer: outstanding buffers */
 417                 sk->sk_timer.expires  = jiffies + 10 * HZ;
 418                 sk->sk_timer.function = x25_destroy_timer;
 419                 add_timer(&sk->sk_timer);
 420         } else {
 421                 /* drop last reference so sock_put will free */
 422                 __sock_put(sk);
 423         }
 424 }
 425
 426 void x25_destroy_socket_from_timer(struct sock *sk)
 427 {
 428         sock_hold(sk);
 429         bh_lock_sock(sk);
 430         __x25_destroy_socket(sk);
 431         bh_unlock_sock(sk);
 432         sock_put(sk);
 433 }
 434
 435 /*
 436  *      Handling for system calls applied via the various interfaces to a
 437  *      X.25 socket object.
 438  */
 439
 440 static int x25_setsockopt(struct socket *sock, int level, int optname,
 441                           char __user *optval, unsigned int optlen)
 442 {
 443         int opt;
 444         struct sock *sk = sock->sk;
 445         int rc = -ENOPROTOOPT;
 446
 447         if (level != SOL_X25 || optname != X25_QBITINCL)
 448                 goto out;
 449
 450         rc = -EINVAL;
 451         if (optlen < sizeof(int))
 452                 goto out;
 453
 454         rc = -EFAULT;
 455         if (get_user(opt, (int __user *)optval))
 456                 goto out;
 457
 458         if (opt)
 459                 set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 460         else
 461                 clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 462         rc = 0;
 463 out:
 464         return rc;
 465 }
 466
 467 static int x25_getsockopt(struct socket *sock, int level, int optname,
 468                           char __user *optval, int __user *optlen)
 469 {
 470         struct sock *sk = sock->sk;
 471         int val, len, rc = -ENOPROTOOPT;
 472
 473         if (level != SOL_X25 || optname != X25_QBITINCL)
 474                 goto out;
 475
 476         rc = -EFAULT;
 477         if (get_user(len, optlen))
 478                 goto out;
 479
 480         len = min_t(unsigned int, len, sizeof(int));
 481
 482         rc = -EINVAL;
 483         if (len < 0)
 484                 goto out;
 485
 486         rc = -EFAULT;
 487         if (put_user(len, optlen))
 488                 goto out;
 489
 490         val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 491         rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
 492 out:
 493         return rc;
 494 }
 495
 496 static int x25_listen(struct socket *sock, int backlog)
 497 {
 498         struct sock *sk = sock->sk;
 499         int rc = -EOPNOTSUPP;
 500
 501         lock_sock(sk);
 502         if (sk->sk_state != TCP_LISTEN) {
 503                 memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 504                 sk->sk_max_ack_backlog = backlog;
 505                 sk->sk_state           = TCP_LISTEN;
 506                 rc = 0;
 507         }
 508         release_sock(sk);
 509
 510         return rc;
 511 }
 512
 513 static struct proto x25_proto = {
 514         .name     = "X25",
 515         .owner    = THIS_MODULE,
 516         .obj_size = sizeof(struct x25_sock),
 517 };
 518
 519 static struct sock *x25_alloc_socket(struct net *net, int kern)
 520 {
 521         struct x25_sock *x25;
 522         struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 523
 524         if (!sk)
 525                 goto out;
 526
 527         sock_init_data(NULL, sk);
 528
 529         x25 = x25_sk(sk);
 530         skb_queue_head_init(&x25->ack_queue);
 531         skb_queue_head_init(&x25->fragment_queue);
 532         skb_queue_head_init(&x25->interrupt_in_queue);
 533         skb_queue_head_init(&x25->interrupt_out_queue);
 534 out:
 535         return sk;
 536 }
 537
 538 static int x25_create(struct net *net, struct socket *sock, int protocol,
 539                       int kern)
 540 {
 541         struct sock *sk;
 542         struct x25_sock *x25;
 543         int rc = -EAFNOSUPPORT;
 544
 545         if (!net_eq(net, &init_net))
 546                 goto out;
 547
 548         rc = -ESOCKTNOSUPPORT;
 549         if (sock->type != SOCK_SEQPACKET)
 550                 goto out;
 551
 552         rc = -EINVAL;
 553         if (protocol)
 554                 goto out;
 555
 556         rc = -ENOBUFS;
 557         if ((sk = x25_alloc_socket(net, kern)) == NULL)
 558                 goto out;
 559
 560         x25 = x25_sk(sk);
 561
 562         sock_init_data(sock, sk);
 563
 564         x25_init_timers(sk);
 565
 566         sock->ops    = &x25_proto_ops;
 567         sk->sk_protocol = protocol;
 568         sk->sk_backlog_rcv = x25_backlog_rcv;
 569
 570         x25->t21   = sysctl_x25_call_request_timeout;
 571         x25->t22   = sysctl_x25_reset_request_timeout;
 572         x25->t23   = sysctl_x25_clear_request_timeout;
 573         x25->t2    = sysctl_x25_ack_holdback_timeout;
 574         x25->state = X25_STATE_0;
 575         x25->cudmatchlength = 0;
 576         set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);     /* normally no cud  */
 577                                                         /* on call accept   */
 578
 579         x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 580         x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 581         x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 582         x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 583         x25->facilities.throughput  = 0;        /* by default don't negotiate
 584                                                    throughput */
 585         x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 586         x25->dte_facilities.calling_len = 0;
 587         x25->dte_facilities.called_len = 0;
 588         memset(x25->dte_facilities.called_ae, '\0',
 589                         sizeof(x25->dte_facilities.called_ae));
 590         memset(x25->dte_facilities.calling_ae, '\0',
 591                         sizeof(x25->dte_facilities.calling_ae));
 592
 593         rc = 0;
 594 out:
 595         return rc;
 596 }
 597
 598 static struct sock *x25_make_new(struct sock *osk)
 599 {
 600         struct sock *sk = NULL;
 601         struct x25_sock *x25, *ox25;
 602
 603         if (osk->sk_type != SOCK_SEQPACKET)
 604                 goto out;
 605
 606         if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 607                 goto out;
 608
 609         x25 = x25_sk(sk);
 610
 611         sk->sk_type        = osk->sk_type;
 612         sk->sk_priority    = osk->sk_priority;
 613         sk->sk_protocol    = osk->sk_protocol;
 614         sk->sk_rcvbuf      = osk->sk_rcvbuf;
 615         sk->sk_sndbuf      = osk->sk_sndbuf;
 616         sk->sk_state       = TCP_ESTABLISHED;
 617         sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 618         sock_copy_flags(sk, osk);
 619
 620         ox25 = x25_sk(osk);
 621         x25->t21        = ox25->t21;
 622         x25->t22        = ox25->t22;
 623         x25->t23        = ox25->t23;
 624         x25->t2         = ox25->t2;
 625         x25->flags      = ox25->flags;
 626         x25->facilities = ox25->facilities;
 627         x25->dte_facilities = ox25->dte_facilities;
 628         x25->cudmatchlength = ox25->cudmatchlength;
 629
 630         clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 631         x25_init_timers(sk);
 632 out:
 633         return sk;
 634 }
 635
 636 static int x25_release(struct socket *sock)
 637 {
 638         struct sock *sk = sock->sk;
 639         struct x25_sock *x25;
 640
 641         if (!sk)
 642                 return 0;
 643
 644         x25 = x25_sk(sk);
 645
 646         sock_hold(sk);
 647         lock_sock(sk);
 648         switch (x25->state) {
 649
 650                 case X25_STATE_0:
 651                 case X25_STATE_2:
 652                         x25_disconnect(sk, 0, 0, 0);
 653                         __x25_destroy_socket(sk);
 654                         goto out;
 655
 656                 case X25_STATE_1:
 657                 case X25_STATE_3:
 658                 case X25_STATE_4:
 659                         x25_clear_queues(sk);
 660                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 661                         x25_start_t23timer(sk);
 662                         x25->state = X25_STATE_2;
 663                         sk->sk_state    = TCP_CLOSE;
 664                         sk->sk_shutdown |= SEND_SHUTDOWN;
 665                         sk->sk_state_change(sk);
 666                         sock_set_flag(sk, SOCK_DEAD);
 667                         sock_set_flag(sk, SOCK_DESTROY);
 668                         break;
 669         }
 670
 671         sock_orphan(sk);
 672 out:
 673         release_sock(sk);
 674         sock_put(sk);
 675         return 0;
 676 }
 677
 678 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 679 {
 680         struct sock *sk = sock->sk;
 681         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 682         int len, i, rc = 0;
 683
 684         if (!sock_flag(sk, SOCK_ZAPPED) ||
 685             addr_len != sizeof(struct sockaddr_x25) ||
 686             addr->sx25_family != AF_X25) {
 687                 rc = -EINVAL;
 688                 goto out;
 689         }
 690
 691         len = strlen(addr->sx25_addr.x25_addr);
 692         for (i = 0; i < len; i++) {
 693                 if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 694                         rc = -EINVAL;
 695                         goto out;
 696                 }
 697         }
 698
 699         lock_sock(sk);
 700         x25_sk(sk)->source_addr = addr->sx25_addr;
 701         x25_insert_socket(sk);
 702         sock_reset_flag(sk, SOCK_ZAPPED);
 703         release_sock(sk);
 704         SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
 705 out:
 706         return rc;
 707 }
 708
 709 static int x25_wait_for_connection_establishment(struct sock *sk)
 710 {
 711         DECLARE_WAITQUEUE(wait, current);
 712         int rc;
 713
 714         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 715         for (;;) {
 716                 __set_current_state(TASK_INTERRUPTIBLE);
 717                 rc = -ERESTARTSYS;
 718                 if (signal_pending(current))
 719                         break;
 720                 rc = sock_error(sk);
 721                 if (rc) {
 722                         sk->sk_socket->state = SS_UNCONNECTED;
 723                         break;
 724                 }
 725                 rc = 0;
 726                 if (sk->sk_state != TCP_ESTABLISHED) {
 727                         release_sock(sk);
 728                         schedule();
 729                         lock_sock(sk);
 730                 } else
 731                         break;
 732         }
 733         __set_current_state(TASK_RUNNING);
 734         remove_wait_queue(sk_sleep(sk), &wait);
 735         return rc;
 736 }
 737
 738 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
 739                        int addr_len, int flags)
 740 {
 741         struct sock *sk = sock->sk;
 742         struct x25_sock *x25 = x25_sk(sk);
 743         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 744         struct x25_route *rt;
 745         int rc = 0;
 746
 747         lock_sock(sk);
 748         if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 749                 sock->state = SS_CONNECTED;
 750                 goto out; /* Connect completed during a ERESTARTSYS event */
 751         }
 752
 753         rc = -ECONNREFUSED;
 754         if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 755                 sock->state = SS_UNCONNECTED;
 756                 goto out;
 757         }
 758
 759         rc = -EISCONN;  /* No reconnect on a seqpacket socket */
 760         if (sk->sk_state == TCP_ESTABLISHED)
 761                 goto out;
 762
 763         sk->sk_state   = TCP_CLOSE;
 764         sock->state = SS_UNCONNECTED;
 765
 766         rc = -EINVAL;
 767         if (addr_len != sizeof(struct sockaddr_x25) ||
 768             addr->sx25_family != AF_X25)
 769                 goto out;
 770
 771         rc = -ENETUNREACH;
 772         rt = x25_get_route(&addr->sx25_addr);
 773         if (!rt)
 774                 goto out;
 775
 776         x25->neighbour = x25_get_neigh(rt->dev);
 777         if (!x25->neighbour)
 778                 goto out_put_route;
 779
 780         x25_limit_facilities(&x25->facilities, x25->neighbour);
 781
 782         x25->lci = x25_new_lci(x25->neighbour);
 783         if (!x25->lci)
 784                 goto out_put_neigh;
 785
 786         rc = -EINVAL;
 787         if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 788                 goto out_put_neigh;
 789
 790         if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 791                 memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 792
 793         x25->dest_addr = addr->sx25_addr;
 794
 795         /* Move to connecting socket, start sending Connect Requests */
 796         sock->state   = SS_CONNECTING;
 797         sk->sk_state  = TCP_SYN_SENT;
 798
 799         x25->state = X25_STATE_1;
 800
 801         x25_write_internal(sk, X25_CALL_REQUEST);
 802
 803         x25_start_heartbeat(sk);
 804         x25_start_t21timer(sk);
 805
 806         /* Now the loop */
 807         rc = -EINPROGRESS;
 808         if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 809                 goto out_put_neigh;
 810
 811         rc = x25_wait_for_connection_establishment(sk);
 812         if (rc)
 813                 goto out_put_neigh;
 814
 815         sock->state = SS_CONNECTED;
 816         rc = 0;
 817 out_put_neigh:
 818         if (rc)
 819                 x25_neigh_put(x25->neighbour);
 820 out_put_route:
 821         x25_route_put(rt);
 822 out:
 823         release_sock(sk);
 824         return rc;
 825 }
 826
 827 static int x25_wait_for_data(struct sock *sk, long timeout)
 828 {
 829         DECLARE_WAITQUEUE(wait, current);
 830         int rc = 0;
 831
 832         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 833         for (;;) {
 834                 __set_current_state(TASK_INTERRUPTIBLE);
 835                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 836                         break;
 837                 rc = -ERESTARTSYS;
 838                 if (signal_pending(current))
 839                         break;
 840                 rc = -EAGAIN;
 841                 if (!timeout)
 842                         break;
 843                 rc = 0;
 844                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 845                         release_sock(sk);
 846                         timeout = schedule_timeout(timeout);
 847                         lock_sock(sk);
 848                 } else
 849                         break;
 850         }
 851         __set_current_state(TASK_RUNNING);
 852         remove_wait_queue(sk_sleep(sk), &wait);
 853         return rc;
 854 }
 855
 856 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 857                       bool kern)
 858 {
 859         struct sock *sk = sock->sk;
 860         struct sock *newsk;
 861         struct sk_buff *skb;
 862         int rc = -EINVAL;
 863
 864         if (!sk)
 865                 goto out;
 866
 867         rc = -EOPNOTSUPP;
 868         if (sk->sk_type != SOCK_SEQPACKET)
 869                 goto out;
 870
 871         lock_sock(sk);
 872         rc = -EINVAL;
 873         if (sk->sk_state != TCP_LISTEN)
 874                 goto out2;
 875
 876         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 877         if (rc)
 878                 goto out2;
 879         skb = skb_dequeue(&sk->sk_receive_queue);
 880         rc = -EINVAL;
 881         if (!skb->sk)
 882                 goto out2;
 883         newsk            = skb->sk;
 884         sock_graft(newsk, newsock);
 885
 886         /* Now attach up the new socket */
 887         skb->sk = NULL;
 888         kfree_skb(skb);
 889         sk->sk_ack_backlog--;
 890         newsock->state = SS_CONNECTED;
 891         rc = 0;
 892 out2:
 893         release_sock(sk);
 894 out:
 895         return rc;
 896 }
 897
 898 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 899                        int peer)
 900 {
 901         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 902         struct sock *sk = sock->sk;
 903         struct x25_sock *x25 = x25_sk(sk);
 904         int rc = 0;
 905
 906         if (peer) {
 907                 if (sk->sk_state != TCP_ESTABLISHED) {
 908                         rc = -ENOTCONN;
 909                         goto out;
 910                 }
 911                 sx25->sx25_addr = x25->dest_addr;
 912         } else
 913                 sx25->sx25_addr = x25->source_addr;
 914
 915         sx25->sx25_family = AF_X25;
 916         rc = sizeof(*sx25);
 917
 918 out:
 919         return rc;
 920 }
 921
 922 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 923                         unsigned int lci)
 924 {
 925         struct sock *sk;
 926         struct sock *make;
 927         struct x25_sock *makex25;
 928         struct x25_address source_addr, dest_addr;
 929         struct x25_facilities facilities;
 930         struct x25_dte_facilities dte_facilities;
 931         int len, addr_len, rc;
 932
 933         /*
 934          *      Remove the LCI and frame type.
 935          */
 936         skb_pull(skb, X25_STD_MIN_LEN);
 937
 938         /*
 939          *      Extract the X.25 addresses and convert them to ASCII strings,
 940          *      and remove them.
 941          *
 942          *      Address block is mandatory in call request packets
 943          */
 944         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 945         if (addr_len <= 0)
 946                 goto out_clear_request;
 947         skb_pull(skb, addr_len);
 948
 949         /*
 950          *      Get the length of the facilities, skip past them for the moment
 951          *      get the call user data because this is needed to determine
 952          *      the correct listener
 953          *
 954          *      Facilities length is mandatory in call request packets
 955          */
 956         if (!pskb_may_pull(skb, 1))
 957                 goto out_clear_request;
 958         len = skb->data[0] + 1;
 959         if (!pskb_may_pull(skb, len))
 960                 goto out_clear_request;
 961         skb_pull(skb,len);
 962
 963         /*
 964          *      Ensure that the amount of call user data is valid.
 965          */
 966         if (skb->len > X25_MAX_CUD_LEN)
 967                 goto out_clear_request;
 968
 969         /*
 970          *      Get all the call user data so it can be used in
 971          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 972          */
 973         if (!pskb_may_pull(skb, skb->len))
 974                 goto out_clear_request;
 975
 976         /*
 977          *      Find a listener for the particular address/cud pair.
 978          */
 979         sk = x25_find_listener(&source_addr,skb);
 980         skb_push(skb,len);
 981
 982         if (sk != NULL && sk_acceptq_is_full(sk)) {
 983                 goto out_sock_put;
 984         }
 985
 986         /*
 987          *      We dont have any listeners for this incoming call.
 988          *      Try forwarding it.
 989          */
 990         if (sk == NULL) {
 991                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
 992                 if (sysctl_x25_forward &&
 993                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
 994                 {
 995                         /* Call was forwarded, dont process it any more */
 996                         kfree_skb(skb);
 997                         rc = 1;
 998                         goto out;
 999                 } else {
1000                         /* No listeners, can't forward, clear the call */
1001                         goto out_clear_request;
1002                 }
1003         }
1004
1005         /*
1006          *      Try to reach a compromise on the requested facilities.
1007          */
1008         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1009         if (len == -1)
1010                 goto out_sock_put;
1011
1012         /*
1013          * current neighbour/link might impose additional limits
1014          * on certain facilties
1015          */
1016
1017         x25_limit_facilities(&facilities, nb);
1018
1019         /*
1020          *      Try to create a new socket.
1021          */
1022         make = x25_make_new(sk);
1023         if (!make)
1024                 goto out_sock_put;
1025
1026         /*
1027          *      Remove the facilities
1028          */
1029         skb_pull(skb, len);
1030
1031         skb->sk     = make;
1032         make->sk_state = TCP_ESTABLISHED;
1033
1034         makex25 = x25_sk(make);
1035         makex25->lci           = lci;
1036         makex25->dest_addr     = dest_addr;
1037         makex25->source_addr   = source_addr;
1038         makex25->neighbour     = nb;
1039         makex25->facilities    = facilities;
1040         makex25->dte_facilities= dte_facilities;
1041         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1042         /* ensure no reverse facil on accept */
1043         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1044         /* ensure no calling address extension on accept */
1045         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1046         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1047
1048         /* Normally all calls are accepted immediately */
1049         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1050                 x25_write_internal(make, X25_CALL_ACCEPTED);
1051                 makex25->state = X25_STATE_3;
1052         }
1053
1054         /*
1055          *      Incoming Call User Data.
1056          */
1057         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1058         makex25->calluserdata.cudlength = skb->len;
1059
1060         sk->sk_ack_backlog++;
1061
1062         x25_insert_socket(make);
1063
1064         skb_queue_head(&sk->sk_receive_queue, skb);
1065
1066         x25_start_heartbeat(make);
1067
1068         if (!sock_flag(sk, SOCK_DEAD))
1069                 sk->sk_data_ready(sk);
1070         rc = 1;
1071         sock_put(sk);
1072 out:
1073         return rc;
1074 out_sock_put:
1075         sock_put(sk);
1076 out_clear_request:
1077         rc = 0;
1078         x25_transmit_clear_request(nb, lci, 0x01);
1079         goto out;
1080 }
1081
1082 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1083 {
1084         struct sock *sk = sock->sk;
1085         struct x25_sock *x25 = x25_sk(sk);
1086         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1087         struct sockaddr_x25 sx25;
1088         struct sk_buff *skb;
1089         unsigned char *asmptr;
1090         int noblock = msg->msg_flags & MSG_DONTWAIT;
1091         size_t size;
1092         int qbit = 0, rc = -EINVAL;
1093
1094         lock_sock(sk);
1095         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1096                 goto out;
1097
1098         /* we currently don't support segmented records at the user interface */
1099         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1100                 goto out;
1101
1102         rc = -EADDRNOTAVAIL;
1103         if (sock_flag(sk, SOCK_ZAPPED))
1104                 goto out;
1105
1106         rc = -EPIPE;
1107         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1108                 send_sig(SIGPIPE, current, 0);
1109                 goto out;
1110         }
1111
1112         rc = -ENETUNREACH;
1113         if (!x25->neighbour)
1114                 goto out;
1115
1116         if (usx25) {
1117                 rc = -EINVAL;
1118                 if (msg->msg_namelen < sizeof(sx25))
1119                         goto out;
1120                 memcpy(&sx25, usx25, sizeof(sx25));
1121                 rc = -EISCONN;
1122                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1123                         goto out;
1124                 rc = -EINVAL;
1125                 if (sx25.sx25_family != AF_X25)
1126                         goto out;
1127         } else {
1128                 /*
1129                  *      FIXME 1003.1g - if the socket is like this because
1130                  *      it has become closed (not started closed) we ought
1131                  *      to SIGPIPE, EPIPE;
1132                  */
1133                 rc = -ENOTCONN;
1134                 if (sk->sk_state != TCP_ESTABLISHED)
1135                         goto out;
1136
1137                 sx25.sx25_family = AF_X25;
1138                 sx25.sx25_addr   = x25->dest_addr;
1139         }
1140
1141         /* Sanity check the packet size */
1142         if (len > 65535) {
1143                 rc = -EMSGSIZE;
1144                 goto out;
1145         }
1146
1147         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1148
1149         /* Build a packet */
1150         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1151
1152         if ((msg->msg_flags & MSG_OOB) && len > 32)
1153                 len = 32;
1154
1155         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1156
1157         release_sock(sk);
1158         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1159         lock_sock(sk);
1160         if (!skb)
1161                 goto out;
1162         X25_SKB_CB(skb)->flags = msg->msg_flags;
1163
1164         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1165
1166         /*
1167          *      Put the data on the end
1168          */
1169         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1170
1171         skb_reset_transport_header(skb);
1172         skb_put(skb, len);
1173
1174         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1175         if (rc)
1176                 goto out_kfree_skb;
1177
1178         /*
1179          *      If the Q BIT Include socket option is in force, the first
1180          *      byte of the user data is the logical value of the Q Bit.
1181          */
1182         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1183                 if (!pskb_may_pull(skb, 1))
1184                         goto out_kfree_skb;
1185
1186                 qbit = skb->data[0];
1187                 skb_pull(skb, 1);
1188         }
1189
1190         /*
1191          *      Push down the X.25 header
1192          */
1193         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1194
1195         if (msg->msg_flags & MSG_OOB) {
1196                 if (x25->neighbour->extended) {
1197                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1198                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1199                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1200                         *asmptr++ = X25_INTERRUPT;
1201                 } else {
1202                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1203                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1204                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1205                         *asmptr++ = X25_INTERRUPT;
1206                 }
1207         } else {
1208                 if (x25->neighbour->extended) {
1209                         /* Build an Extended X.25 header */
1210                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1211                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1212                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1213                         *asmptr++ = X25_DATA;
1214                         *asmptr++ = X25_DATA;
1215                 } else {
1216                         /* Build an Standard X.25 header */
1217                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1218                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1219                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1220                         *asmptr++ = X25_DATA;
1221                 }
1222
1223                 if (qbit)
1224                         skb->data[0] |= X25_Q_BIT;
1225         }
1226
1227         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1228         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1229
1230         rc = -ENOTCONN;
1231         if (sk->sk_state != TCP_ESTABLISHED)
1232                 goto out_kfree_skb;
1233
1234         if (msg->msg_flags & MSG_OOB)
1235                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1236         else {
1237                 rc = x25_output(sk, skb);
1238                 len = rc;
1239                 if (rc < 0)
1240                         kfree_skb(skb);
1241                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1242                         len++;
1243         }
1244
1245         x25_kick(sk);
1246         rc = len;
1247 out:
1248         release_sock(sk);
1249         return rc;
1250 out_kfree_skb:
1251         kfree_skb(skb);
1252         goto out;
1253 }
1254
1255
1256 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1257                        int flags)
1258 {
1259         struct sock *sk = sock->sk;
1260         struct x25_sock *x25 = x25_sk(sk);
1261         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1262         size_t copied;
1263         int qbit, header_len;
1264         struct sk_buff *skb;
1265         unsigned char *asmptr;
1266         int rc = -ENOTCONN;
1267
1268         lock_sock(sk);
1269
1270         if (x25->neighbour == NULL)
1271                 goto out;
1272
1273         header_len = x25->neighbour->extended ?
1274                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1275
1276         /*
1277          * This works for seqpacket too. The receiver has ordered the queue for
1278          * us! We do one quick check first though
1279          */
1280         if (sk->sk_state != TCP_ESTABLISHED)
1281                 goto out;
1282
1283         if (flags & MSG_OOB) {
1284                 rc = -EINVAL;
1285                 if (sock_flag(sk, SOCK_URGINLINE) ||
1286                     !skb_peek(&x25->interrupt_in_queue))
1287                         goto out;
1288
1289                 skb = skb_dequeue(&x25->interrupt_in_queue);
1290
1291                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1292                         goto out_free_dgram;
1293
1294                 skb_pull(skb, X25_STD_MIN_LEN);
1295
1296                 /*
1297                  *      No Q bit information on Interrupt data.
1298                  */
1299                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1300                         asmptr  = skb_push(skb, 1);
1301                         *asmptr = 0x00;
1302                 }
1303
1304                 msg->msg_flags |= MSG_OOB;
1305         } else {
1306                 /* Now we can treat all alike */
1307                 release_sock(sk);
1308                 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1309                                         flags & MSG_DONTWAIT, &rc);
1310                 lock_sock(sk);
1311                 if (!skb)
1312                         goto out;
1313
1314                 if (!pskb_may_pull(skb, header_len))
1315                         goto out_free_dgram;
1316
1317                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1318
1319                 skb_pull(skb, header_len);
1320
1321                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1322                         asmptr  = skb_push(skb, 1);
1323                         *asmptr = qbit;
1324                 }
1325         }
1326
1327         skb_reset_transport_header(skb);
1328         copied = skb->len;
1329
1330         if (copied > size) {
1331                 copied = size;
1332                 msg->msg_flags |= MSG_TRUNC;
1333         }
1334
1335         /* Currently, each datagram always contains a complete record */
1336         msg->msg_flags |= MSG_EOR;
1337
1338         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1339         if (rc)
1340                 goto out_free_dgram;
1341
1342         if (sx25) {
1343                 sx25->sx25_family = AF_X25;
1344                 sx25->sx25_addr   = x25->dest_addr;
1345                 msg->msg_namelen = sizeof(*sx25);
1346         }
1347
1348         x25_check_rbuf(sk);
1349         rc = copied;
1350 out_free_dgram:
1351         skb_free_datagram(sk, skb);
1352 out:
1353         release_sock(sk);
1354         return rc;
1355 }
1356
1357
1358 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1359 {
1360         struct sock *sk = sock->sk;
1361         struct x25_sock *x25 = x25_sk(sk);
1362         void __user *argp = (void __user *)arg;
1363         int rc;
1364
1365         switch (cmd) {
1366         case TIOCOUTQ: {
1367                 int amount;
1368
1369                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1370                 if (amount < 0)
1371                         amount = 0;
1372                 rc = put_user(amount, (unsigned int __user *)argp);
1373                 break;
1374         }
1375
1376         case TIOCINQ: {
1377                 struct sk_buff *skb;
1378                 int amount = 0;
1379                 /*
1380                  * These two are safe on a single CPU system as
1381                  * only user tasks fiddle here
1382                  */
1383                 lock_sock(sk);
1384                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1385                         amount = skb->len;
1386                 release_sock(sk);
1387                 rc = put_user(amount, (unsigned int __user *)argp);
1388                 break;
1389         }
1390
1391         case SIOCGSTAMP:
1392                 rc = -EINVAL;
1393                 if (sk)
1394                         rc = sock_get_timestamp(sk,
1395                                                 (struct timeval __user *)argp);
1396                 break;
1397         case SIOCGSTAMPNS:
1398                 rc = -EINVAL;
1399                 if (sk)
1400                         rc = sock_get_timestampns(sk,
1401                                         (struct timespec __user *)argp);
1402                 break;
1403         case SIOCGIFADDR:
1404         case SIOCSIFADDR:
1405         case SIOCGIFDSTADDR:
1406         case SIOCSIFDSTADDR:
1407         case SIOCGIFBRDADDR:
1408         case SIOCSIFBRDADDR:
1409         case SIOCGIFNETMASK:
1410         case SIOCSIFNETMASK:
1411         case SIOCGIFMETRIC:
1412         case SIOCSIFMETRIC:
1413                 rc = -EINVAL;
1414                 break;
1415         case SIOCADDRT:
1416         case SIOCDELRT:
1417                 rc = -EPERM;
1418                 if (!capable(CAP_NET_ADMIN))
1419                         break;
1420                 rc = x25_route_ioctl(cmd, argp);
1421                 break;
1422         case SIOCX25GSUBSCRIP:
1423                 rc = x25_subscr_ioctl(cmd, argp);
1424                 break;
1425         case SIOCX25SSUBSCRIP:
1426                 rc = -EPERM;
1427                 if (!capable(CAP_NET_ADMIN))
1428                         break;
1429                 rc = x25_subscr_ioctl(cmd, argp);
1430                 break;
1431         case SIOCX25GFACILITIES: {
1432                 lock_sock(sk);
1433                 rc = copy_to_user(argp, &x25->facilities,
1434                                   sizeof(x25->facilities))
1435                         ? -EFAULT : 0;
1436                 release_sock(sk);
1437                 break;
1438         }
1439
1440         case SIOCX25SFACILITIES: {
1441                 struct x25_facilities facilities;
1442                 rc = -EFAULT;
1443                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1444                         break;
1445                 rc = -EINVAL;
1446                 lock_sock(sk);
1447                 if (sk->sk_state != TCP_LISTEN &&
1448                     sk->sk_state != TCP_CLOSE)
1449                         goto out_fac_release;
1450                 if (facilities.pacsize_in < X25_PS16 ||
1451                     facilities.pacsize_in > X25_PS4096)
1452                         goto out_fac_release;
1453                 if (facilities.pacsize_out < X25_PS16 ||
1454                     facilities.pacsize_out > X25_PS4096)
1455                         goto out_fac_release;
1456                 if (facilities.winsize_in < 1 ||
1457                     facilities.winsize_in > 127)
1458                         goto out_fac_release;
1459                 if (facilities.throughput) {
1460                         int out = facilities.throughput & 0xf0;
1461                         int in  = facilities.throughput & 0x0f;
1462                         if (!out)
1463                                 facilities.throughput |=
1464                                         X25_DEFAULT_THROUGHPUT << 4;
1465                         else if (out < 0x30 || out > 0xD0)
1466                                 goto out_fac_release;
1467                         if (!in)
1468                                 facilities.throughput |=
1469                                         X25_DEFAULT_THROUGHPUT;
1470                         else if (in < 0x03 || in > 0x0D)
1471                                 goto out_fac_release;
1472                 }
1473                 if (facilities.reverse &&
1474                     (facilities.reverse & 0x81) != 0x81)
1475                         goto out_fac_release;
1476                 x25->facilities = facilities;
1477                 rc = 0;
1478 out_fac_release:
1479                 release_sock(sk);
1480                 break;
1481         }
1482
1483         case SIOCX25GDTEFACILITIES: {
1484                 lock_sock(sk);
1485                 rc = copy_to_user(argp, &x25->dte_facilities,
1486                                   sizeof(x25->dte_facilities));
1487                 release_sock(sk);
1488                 if (rc)
1489                         rc = -EFAULT;
1490                 break;
1491         }
1492
1493         case SIOCX25SDTEFACILITIES: {
1494                 struct x25_dte_facilities dtefacs;
1495                 rc = -EFAULT;
1496                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1497                         break;
1498                 rc = -EINVAL;
1499                 lock_sock(sk);
1500                 if (sk->sk_state != TCP_LISTEN &&
1501                     sk->sk_state != TCP_CLOSE)
1502                         goto out_dtefac_release;
1503                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1504                         goto out_dtefac_release;
1505                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1506                         goto out_dtefac_release;
1507                 x25->dte_facilities = dtefacs;
1508                 rc = 0;
1509 out_dtefac_release:
1510                 release_sock(sk);
1511                 break;
1512         }
1513
1514         case SIOCX25GCALLUSERDATA: {
1515                 lock_sock(sk);
1516                 rc = copy_to_user(argp, &x25->calluserdata,
1517                                   sizeof(x25->calluserdata))
1518                         ? -EFAULT : 0;
1519                 release_sock(sk);
1520                 break;
1521         }
1522
1523         case SIOCX25SCALLUSERDATA: {
1524                 struct x25_calluserdata calluserdata;
1525
1526                 rc = -EFAULT;
1527                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1528                         break;
1529                 rc = -EINVAL;
1530                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1531                         break;
1532                 lock_sock(sk);
1533                 x25->calluserdata = calluserdata;
1534                 release_sock(sk);
1535                 rc = 0;
1536                 break;
1537         }
1538
1539         case SIOCX25GCAUSEDIAG: {
1540                 lock_sock(sk);
1541                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1542                         ? -EFAULT : 0;
1543                 release_sock(sk);
1544                 break;
1545         }
1546
1547         case SIOCX25SCAUSEDIAG: {
1548                 struct x25_causediag causediag;
1549                 rc = -EFAULT;
1550                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1551                         break;
1552                 lock_sock(sk);
1553                 x25->causediag = causediag;
1554                 release_sock(sk);
1555                 rc = 0;
1556                 break;
1557
1558         }
1559
1560         case SIOCX25SCUDMATCHLEN: {
1561                 struct x25_subaddr sub_addr;
1562                 rc = -EINVAL;
1563                 lock_sock(sk);
1564                 if(sk->sk_state != TCP_CLOSE)
1565                         goto out_cud_release;
1566                 rc = -EFAULT;
1567                 if (copy_from_user(&sub_addr, argp,
1568                                    sizeof(sub_addr)))
1569                         goto out_cud_release;
1570                 rc = -EINVAL;
1571                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1572                         goto out_cud_release;
1573                 x25->cudmatchlength = sub_addr.cudmatchlength;
1574                 rc = 0;
1575 out_cud_release:
1576                 release_sock(sk);
1577                 break;
1578         }
1579
1580         case SIOCX25CALLACCPTAPPRV: {
1581                 rc = -EINVAL;
1582                 lock_sock(sk);
1583                 if (sk->sk_state == TCP_CLOSE) {
1584                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1585                         rc = 0;
1586                 }
1587                 release_sock(sk);
1588                 break;
1589         }
1590
1591         case SIOCX25SENDCALLACCPT:  {
1592                 rc = -EINVAL;
1593                 lock_sock(sk);
1594                 if (sk->sk_state != TCP_ESTABLISHED)
1595                         goto out_sendcallaccpt_release;
1596                 /* must call accptapprv above */
1597                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1598                         goto out_sendcallaccpt_release;
1599                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1600                 x25->state = X25_STATE_3;
1601                 rc = 0;
1602 out_sendcallaccpt_release:
1603                 release_sock(sk);
1604                 break;
1605         }
1606
1607         default:
1608                 rc = -ENOIOCTLCMD;
1609                 break;
1610         }
1611
1612         return rc;
1613 }
1614
1615 static const struct net_proto_family x25_family_ops = {
1616         .family =       AF_X25,
1617         .create =       x25_create,
1618         .owner  =       THIS_MODULE,
1619 };
1620
1621 #ifdef CONFIG_COMPAT
1622 static int compat_x25_subscr_ioctl(unsigned int cmd,
1623                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1624 {
1625         struct compat_x25_subscrip_struct x25_subscr;
1626         struct x25_neigh *nb;
1627         struct net_device *dev;
1628         int rc = -EINVAL;
1629
1630         rc = -EFAULT;
1631         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1632                 goto out;
1633
1634         rc = -EINVAL;
1635         dev = x25_dev_get(x25_subscr.device);
1636         if (dev == NULL)
1637                 goto out;
1638
1639         nb = x25_get_neigh(dev);
1640         if (nb == NULL)
1641                 goto out_dev_put;
1642
1643         dev_put(dev);
1644
1645         if (cmd == SIOCX25GSUBSCRIP) {
1646                 read_lock_bh(&x25_neigh_list_lock);
1647                 x25_subscr.extended = nb->extended;
1648                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1649                 read_unlock_bh(&x25_neigh_list_lock);
1650                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1651                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1652         } else {
1653                 rc = -EINVAL;
1654                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1655                         rc = 0;
1656                         write_lock_bh(&x25_neigh_list_lock);
1657                         nb->extended = x25_subscr.extended;
1658                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1659                         write_unlock_bh(&x25_neigh_list_lock);
1660                 }
1661         }
1662         x25_neigh_put(nb);
1663 out:
1664         return rc;
1665 out_dev_put:
1666         dev_put(dev);
1667         goto out;
1668 }
1669
1670 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1671                                 unsigned long arg)
1672 {
1673         void __user *argp = compat_ptr(arg);
1674         struct sock *sk = sock->sk;
1675
1676         int rc = -ENOIOCTLCMD;
1677
1678         switch(cmd) {
1679         case TIOCOUTQ:
1680         case TIOCINQ:
1681                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1682                 break;
1683         case SIOCGSTAMP:
1684                 rc = -EINVAL;
1685                 if (sk)
1686                         rc = compat_sock_get_timestamp(sk,
1687                                         (struct timeval __user*)argp);
1688                 break;
1689         case SIOCGSTAMPNS:
1690                 rc = -EINVAL;
1691                 if (sk)
1692                         rc = compat_sock_get_timestampns(sk,
1693                                         (struct timespec __user*)argp);
1694                 break;
1695         case SIOCGIFADDR:
1696         case SIOCSIFADDR:
1697         case SIOCGIFDSTADDR:
1698         case SIOCSIFDSTADDR:
1699         case SIOCGIFBRDADDR:
1700         case SIOCSIFBRDADDR:
1701         case SIOCGIFNETMASK:
1702         case SIOCSIFNETMASK:
1703         case SIOCGIFMETRIC:
1704         case SIOCSIFMETRIC:
1705                 rc = -EINVAL;
1706                 break;
1707         case SIOCADDRT:
1708         case SIOCDELRT:
1709                 rc = -EPERM;
1710                 if (!capable(CAP_NET_ADMIN))
1711                         break;
1712                 rc = x25_route_ioctl(cmd, argp);
1713                 break;
1714         case SIOCX25GSUBSCRIP:
1715                 rc = compat_x25_subscr_ioctl(cmd, argp);
1716                 break;
1717         case SIOCX25SSUBSCRIP:
1718                 rc = -EPERM;
1719                 if (!capable(CAP_NET_ADMIN))
1720                         break;
1721                 rc = compat_x25_subscr_ioctl(cmd, argp);
1722                 break;
1723         case SIOCX25GFACILITIES:
1724         case SIOCX25SFACILITIES:
1725         case SIOCX25GDTEFACILITIES:
1726         case SIOCX25SDTEFACILITIES:
1727         case SIOCX25GCALLUSERDATA:
1728         case SIOCX25SCALLUSERDATA:
1729         case SIOCX25GCAUSEDIAG:
1730         case SIOCX25SCAUSEDIAG:
1731         case SIOCX25SCUDMATCHLEN:
1732         case SIOCX25CALLACCPTAPPRV:
1733         case SIOCX25SENDCALLACCPT:
1734                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1735                 break;
1736         default:
1737                 rc = -ENOIOCTLCMD;
1738                 break;
1739         }
1740         return rc;
1741 }
1742 #endif
1743
1744 static const struct proto_ops x25_proto_ops = {
1745         .family =       AF_X25,
1746         .owner =        THIS_MODULE,
1747         .release =      x25_release,
1748         .bind =         x25_bind,
1749         .connect =      x25_connect,
1750         .socketpair =   sock_no_socketpair,
1751         .accept =       x25_accept,
1752         .getname =      x25_getname,
1753         .poll =         datagram_poll,
1754         .ioctl =        x25_ioctl,
1755 #ifdef CONFIG_COMPAT
1756         .compat_ioctl = compat_x25_ioctl,
1757 #endif
1758         .listen =       x25_listen,
1759         .shutdown =     sock_no_shutdown,
1760         .setsockopt =   x25_setsockopt,
1761         .getsockopt =   x25_getsockopt,
1762         .sendmsg =      x25_sendmsg,
1763         .recvmsg =      x25_recvmsg,
1764         .mmap =         sock_no_mmap,
1765         .sendpage =     sock_no_sendpage,
1766 };
1767
1768 static struct packet_type x25_packet_type __read_mostly = {
1769         .type = cpu_to_be16(ETH_P_X25),
1770         .func = x25_lapb_receive_frame,
1771 };
1772
1773 static struct notifier_block x25_dev_notifier = {
1774         .notifier_call = x25_device_event,
1775 };
1776
1777 void x25_kill_by_neigh(struct x25_neigh *nb)
1778 {
1779         struct sock *s;
1780
1781         write_lock_bh(&x25_list_lock);
1782
1783         sk_for_each(s, &x25_list)
1784                 if (x25_sk(s)->neighbour == nb)
1785                         x25_disconnect(s, ENETUNREACH, 0, 0);
1786
1787         write_unlock_bh(&x25_list_lock);
1788
1789         /* Remove any related forwards */
1790         x25_clear_forward_by_dev(nb->dev);
1791 }
1792
1793 static int __init x25_init(void)
1794 {
1795         int rc;
1796
1797         rc = proto_register(&x25_proto, 0);
1798         if (rc)
1799                 goto out;
1800
1801         rc = sock_register(&x25_family_ops);
1802         if (rc)
1803                 goto out_proto;
1804
1805         dev_add_pack(&x25_packet_type);
1806
1807         rc = register_netdevice_notifier(&x25_dev_notifier);
1808         if (rc)
1809                 goto out_sock;
1810
1811         rc = x25_register_sysctl();
1812         if (rc)
1813                 goto out_dev;
1814
1815         rc = x25_proc_init();
1816         if (rc)
1817                 goto out_sysctl;
1818
1819         pr_info("Linux Version 0.2\n");
1820
1821 out:
1822         return rc;
1823 out_sysctl:
1824         x25_unregister_sysctl();
1825 out_dev:
1826         unregister_netdevice_notifier(&x25_dev_notifier);
1827 out_sock:
1828         dev_remove_pack(&x25_packet_type);
1829         sock_unregister(AF_X25);
1830 out_proto:
1831         proto_unregister(&x25_proto);
1832         goto out;
1833 }
1834 module_init(x25_init);
1835
1836 static void __exit x25_exit(void)
1837 {
1838         x25_proc_exit();
1839         x25_link_free();
1840         x25_route_free();
1841
1842         x25_unregister_sysctl();
1843
1844         unregister_netdevice_notifier(&x25_dev_notifier);
1845
1846         dev_remove_pack(&x25_packet_type);
1847
1848         sock_unregister(AF_X25);
1849         proto_unregister(&x25_proto);
1850 }
1851 module_exit(x25_exit);
1852
1853 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1854 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1855 MODULE_LICENSE("GPL");
1856 MODULE_ALIAS_NETPROTO(PF_X25);