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