net/x25/af_x25.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      X.25 Packet Layer release 002
   4  *
   5  *      This is ALPHA test software. This code may break your machine,
   6  *      randomly fail to work with new releases, misbehave and/or generally
   7  *      screw up. It might even work.
   8  *
   9  *      This code REQUIRES 2.1.15 or higher
  10  *
  11  *      History
  12  *      X.25 001        Jonathan Naylor Started coding.
  13  *      X.25 002        Jonathan Naylor Centralised disconnect handling.
  14  *                                      New timer architecture.
  15  *      2000-03-11      Henner Eisen    MSG_EOR handling more POSIX compliant.
  16  *      2000-03-22      Daniela Squassoni Allowed disabling/enabling of
  17  *                                        facilities negotiation and increased
  18  *                                        the throughput upper limit.
  19  *      2000-08-27      Arnaldo C. Melo s/suser/capable/ + micro cleanups
  20  *      2000-09-04      Henner Eisen    Set sock->state in x25_accept().
  21  *                                      Fixed x25_output() related skb leakage.
  22  *      2000-10-02      Henner Eisen    Made x25_kick() single threaded per socket.
  23  *      2000-10-27      Henner Eisen    MSG_DONTWAIT for fragment allocation.
  24  *      2000-11-14      Henner Eisen    Closing datalink from NETDEV_GOING_DOWN
  25  *      2002-10-06      Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
  26  *                                      x25_proc.c, using seq_file
  27  *      2005-04-02      Shaun Pereira   Selective sub address matching
  28  *                                      with call user data
  29  *      2005-04-15      Shaun Pereira   Fast select with no restriction on
  30  *                                      response
  31  */
  32
  33 #define pr_fmt(fmt) "X25: " fmt
  34
  35 #include <linux/module.h>
  36 #include <linux/capability.h>
  37 #include <linux/errno.h>
  38 #include <linux/kernel.h>
  39 #include <linux/sched/signal.h>
  40 #include <linux/timer.h>
  41 #include <linux/string.h>
  42 #include <linux/net.h>
  43 #include <linux/netdevice.h>
  44 #include <linux/if_arp.h>
  45 #include <linux/skbuff.h>
  46 #include <linux/slab.h>
  47 #include <net/sock.h>
  48 #include <net/tcp_states.h>
  49 #include <linux/uaccess.h>
  50 #include <linux/fcntl.h>
  51 #include <linux/termios.h>      /* For TIOCINQ/OUTQ */
  52 #include <linux/notifier.h>
  53 #include <linux/init.h>
  54 #include <linux/compat.h>
  55 #include <linux/ctype.h>
  56
  57 #include <net/x25.h>
  58 #include <net/compat.h>
  59
  60 int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
  61 int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
  62 int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
  63 int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
  64 int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
  65 int sysctl_x25_forward                 = 0;
  66
  67 HLIST_HEAD(x25_list);
  68 DEFINE_RWLOCK(x25_list_lock);
  69
  70 static const struct proto_ops x25_proto_ops;
  71
  72 static const struct x25_address null_x25_address = {"               "};
  73
  74 #ifdef CONFIG_COMPAT
  75 struct compat_x25_subscrip_struct {
  76         char device[200-sizeof(compat_ulong_t)];
  77         compat_ulong_t global_facil_mask;
  78         compat_uint_t extended;
  79 };
  80 #endif
  81
  82
  83 int x25_parse_address_block(struct sk_buff *skb,
  84                 struct x25_address *called_addr,
  85                 struct x25_address *calling_addr)
  86 {
  87         unsigned char len;
  88         int needed;
  89         int rc;
  90
  91         if (!pskb_may_pull(skb, 1)) {
  92                 /* packet has no address block */
  93                 rc = 0;
  94                 goto empty;
  95         }
  96
  97         len = *skb->data;
  98         needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2;
  99
 100         if (!pskb_may_pull(skb, needed)) {
 101                 /* packet is too short to hold the addresses it claims
 102                    to hold */
 103                 rc = -1;
 104                 goto empty;
 105         }
 106
 107         return x25_addr_ntoa(skb->data, called_addr, calling_addr);
 108
 109 empty:
 110         *called_addr->x25_addr = 0;
 111         *calling_addr->x25_addr = 0;
 112
 113         return rc;
 114 }
 115
 116
 117 int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
 118                   struct x25_address *calling_addr)
 119 {
 120         unsigned int called_len, calling_len;
 121         char *called, *calling;
 122         unsigned int i;
 123
 124         called_len  = (*p >> 0) & 0x0F;
 125         calling_len = (*p >> 4) & 0x0F;
 126
 127         called  = called_addr->x25_addr;
 128         calling = calling_addr->x25_addr;
 129         p++;
 130
 131         for (i = 0; i < (called_len + calling_len); i++) {
 132                 if (i < called_len) {
 133                         if (i % 2 != 0) {
 134                                 *called++ = ((*p >> 0) & 0x0F) + '0';
 135                                 p++;
 136                         } else {
 137                                 *called++ = ((*p >> 4) & 0x0F) + '0';
 138                         }
 139                 } else {
 140                         if (i % 2 != 0) {
 141                                 *calling++ = ((*p >> 0) & 0x0F) + '0';
 142                                 p++;
 143                         } else {
 144                                 *calling++ = ((*p >> 4) & 0x0F) + '0';
 145                         }
 146                 }
 147         }
 148
 149         *called = *calling = '\0';
 150
 151         return 1 + (called_len + calling_len + 1) / 2;
 152 }
 153
 154 int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
 155                   struct x25_address *calling_addr)
 156 {
 157         unsigned int called_len, calling_len;
 158         char *called, *calling;
 159         int i;
 160
 161         called  = called_addr->x25_addr;
 162         calling = calling_addr->x25_addr;
 163
 164         called_len  = strlen(called);
 165         calling_len = strlen(calling);
 166
 167         *p++ = (calling_len << 4) | (called_len << 0);
 168
 169         for (i = 0; i < (called_len + calling_len); i++) {
 170                 if (i < called_len) {
 171                         if (i % 2 != 0) {
 172                                 *p |= (*called++ - '0') << 0;
 173                                 p++;
 174                         } else {
 175                                 *p = 0x00;
 176                                 *p |= (*called++ - '0') << 4;
 177                         }
 178                 } else {
 179                         if (i % 2 != 0) {
 180                                 *p |= (*calling++ - '0') << 0;
 181                                 p++;
 182                         } else {
 183                                 *p = 0x00;
 184                                 *p |= (*calling++ - '0') << 4;
 185                         }
 186                 }
 187         }
 188
 189         return 1 + (called_len + calling_len + 1) / 2;
 190 }
 191
 192 /*
 193  *      Socket removal during an interrupt is now safe.
 194  */
 195 static void x25_remove_socket(struct sock *sk)
 196 {
 197         write_lock_bh(&x25_list_lock);
 198         sk_del_node_init(sk);
 199         write_unlock_bh(&x25_list_lock);
 200 }
 201
 202 /*
 203  *      Kill all bound sockets on a dropped device.
 204  */
 205 static void x25_kill_by_device(struct net_device *dev)
 206 {
 207         struct sock *s;
 208
 209         write_lock_bh(&x25_list_lock);
 210
 211         sk_for_each(s, &x25_list)
 212                 if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
 213                         x25_disconnect(s, ENETUNREACH, 0, 0);
 214
 215         write_unlock_bh(&x25_list_lock);
 216 }
 217
 218 /*
 219  *      Handle device status changes.
 220  */
 221 static int x25_device_event(struct notifier_block *this, unsigned long event,
 222                             void *ptr)
 223 {
 224         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 225         struct x25_neigh *nb;
 226
 227         if (!net_eq(dev_net(dev), &init_net))
 228                 return NOTIFY_DONE;
 229
 230         if (dev->type == ARPHRD_X25
 231 #if IS_ENABLED(CONFIG_LLC)
 232          || dev->type == ARPHRD_ETHER
 233 #endif
 234          ) {
 235                 switch (event) {
 236                 case NETDEV_UP:
 237                         x25_link_device_up(dev);
 238                         break;
 239                 case NETDEV_GOING_DOWN:
 240                         nb = x25_get_neigh(dev);
 241                         if (nb) {
 242                                 x25_terminate_link(nb);
 243                                 x25_neigh_put(nb);
 244                         }
 245                         break;
 246                 case NETDEV_DOWN:
 247                         x25_kill_by_device(dev);
 248                         x25_route_device_down(dev);
 249                         x25_link_device_down(dev);
 250                         break;
 251                 }
 252         }
 253
 254         return NOTIFY_DONE;
 255 }
 256
 257 /*
 258  *      Add a socket to the bound sockets list.
 259  */
 260 static void x25_insert_socket(struct sock *sk)
 261 {
 262         write_lock_bh(&x25_list_lock);
 263         sk_add_node(sk, &x25_list);
 264         write_unlock_bh(&x25_list_lock);
 265 }
 266
 267 /*
 268  *      Find a socket that wants to accept the Call Request we just
 269  *      received. Check the full list for an address/cud match.
 270  *      If no cuds match return the next_best thing, an address match.
 271  *      Note: if a listening socket has cud set it must only get calls
 272  *      with matching cud.
 273  */
 274 static struct sock *x25_find_listener(struct x25_address *addr,
 275                                         struct sk_buff *skb)
 276 {
 277         struct sock *s;
 278         struct sock *next_best;
 279
 280         read_lock_bh(&x25_list_lock);
 281         next_best = NULL;
 282
 283         sk_for_each(s, &x25_list)
 284                 if ((!strcmp(addr->x25_addr,
 285                         x25_sk(s)->source_addr.x25_addr) ||
 286                                 !strcmp(x25_sk(s)->source_addr.x25_addr,
 287                                         null_x25_address.x25_addr)) &&
 288                                         s->sk_state == TCP_LISTEN) {
 289                         /*
 290                          * Found a listening socket, now check the incoming
 291                          * call user data vs this sockets call user data
 292                          */
 293                         if (x25_sk(s)->cudmatchlength > 0 &&
 294                                 skb->len >= x25_sk(s)->cudmatchlength) {
 295                                 if((memcmp(x25_sk(s)->calluserdata.cuddata,
 296                                         skb->data,
 297                                         x25_sk(s)->cudmatchlength)) == 0) {
 298                                         sock_hold(s);
 299                                         goto found;
 300                                  }
 301                         } else
 302                                 next_best = s;
 303                 }
 304         if (next_best) {
 305                 s = next_best;
 306                 sock_hold(s);
 307                 goto found;
 308         }
 309         s = NULL;
 310 found:
 311         read_unlock_bh(&x25_list_lock);
 312         return s;
 313 }
 314
 315 /*
 316  *      Find a connected X.25 socket given my LCI and neighbour.
 317  */
 318 static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 319 {
 320         struct sock *s;
 321
 322         sk_for_each(s, &x25_list)
 323                 if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
 324                         sock_hold(s);
 325                         goto found;
 326                 }
 327         s = NULL;
 328 found:
 329         return s;
 330 }
 331
 332 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 333 {
 334         struct sock *s;
 335
 336         read_lock_bh(&x25_list_lock);
 337         s = __x25_find_socket(lci, nb);
 338         read_unlock_bh(&x25_list_lock);
 339         return s;
 340 }
 341
 342 /*
 343  *      Find a unique LCI for a given device.
 344  */
 345 static unsigned int x25_new_lci(struct x25_neigh *nb)
 346 {
 347         unsigned int lci = 1;
 348         struct sock *sk;
 349
 350         while ((sk = x25_find_socket(lci, nb)) != NULL) {
 351                 sock_put(sk);
 352                 if (++lci == 4096) {
 353                         lci = 0;
 354                         break;
 355                 }
 356                 cond_resched();
 357         }
 358
 359         return lci;
 360 }
 361
 362 /*
 363  *      Deferred destroy.
 364  */
 365 static void __x25_destroy_socket(struct sock *);
 366
 367 /*
 368  *      handler for deferred kills.
 369  */
 370 static void x25_destroy_timer(struct timer_list *t)
 371 {
 372         struct sock *sk = from_timer(sk, t, sk_timer);
 373
 374         x25_destroy_socket_from_timer(sk);
 375 }
 376
 377 /*
 378  *      This is called from user mode and the timers. Thus it protects itself
 379  *      against interrupt users but doesn't worry about being called during
 380  *      work. Once it is removed from the queue no interrupt or bottom half
 381  *      will touch it and we are (fairly 8-) ) safe.
 382  *      Not static as it's used by the timer
 383  */
 384 static void __x25_destroy_socket(struct sock *sk)
 385 {
 386         struct sk_buff *skb;
 387
 388         x25_stop_heartbeat(sk);
 389         x25_stop_timer(sk);
 390
 391         x25_remove_socket(sk);
 392         x25_clear_queues(sk);           /* Flush the queues */
 393
 394         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 395                 if (skb->sk != sk) {            /* A pending connection */
 396                         /*
 397                          * Queue the unaccepted socket for death
 398                          */
 399                         skb->sk->sk_state = TCP_LISTEN;
 400                         sock_set_flag(skb->sk, SOCK_DEAD);
 401                         x25_start_heartbeat(skb->sk);
 402                         x25_sk(skb->sk)->state = X25_STATE_0;
 403                 }
 404
 405                 kfree_skb(skb);
 406         }
 407
 408         if (sk_has_allocations(sk)) {
 409                 /* Defer: outstanding buffers */
 410                 sk->sk_timer.expires  = jiffies + 10 * HZ;
 411                 sk->sk_timer.function = x25_destroy_timer;
 412                 add_timer(&sk->sk_timer);
 413         } else {
 414                 /* drop last reference so sock_put will free */
 415                 __sock_put(sk);
 416         }
 417 }
 418
 419 void x25_destroy_socket_from_timer(struct sock *sk)
 420 {
 421         sock_hold(sk);
 422         bh_lock_sock(sk);
 423         __x25_destroy_socket(sk);
 424         bh_unlock_sock(sk);
 425         sock_put(sk);
 426 }
 427
 428 /*
 429  *      Handling for system calls applied via the various interfaces to a
 430  *      X.25 socket object.
 431  */
 432
 433 static int x25_setsockopt(struct socket *sock, int level, int optname,
 434                           char __user *optval, unsigned int optlen)
 435 {
 436         int opt;
 437         struct sock *sk = sock->sk;
 438         int rc = -ENOPROTOOPT;
 439
 440         if (level != SOL_X25 || optname != X25_QBITINCL)
 441                 goto out;
 442
 443         rc = -EINVAL;
 444         if (optlen < sizeof(int))
 445                 goto out;
 446
 447         rc = -EFAULT;
 448         if (get_user(opt, (int __user *)optval))
 449                 goto out;
 450
 451         if (opt)
 452                 set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 453         else
 454                 clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 455         rc = 0;
 456 out:
 457         return rc;
 458 }
 459
 460 static int x25_getsockopt(struct socket *sock, int level, int optname,
 461                           char __user *optval, int __user *optlen)
 462 {
 463         struct sock *sk = sock->sk;
 464         int val, len, rc = -ENOPROTOOPT;
 465
 466         if (level != SOL_X25 || optname != X25_QBITINCL)
 467                 goto out;
 468
 469         rc = -EFAULT;
 470         if (get_user(len, optlen))
 471                 goto out;
 472
 473         len = min_t(unsigned int, len, sizeof(int));
 474
 475         rc = -EINVAL;
 476         if (len < 0)
 477                 goto out;
 478
 479         rc = -EFAULT;
 480         if (put_user(len, optlen))
 481                 goto out;
 482
 483         val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 484         rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
 485 out:
 486         return rc;
 487 }
 488
 489 static int x25_listen(struct socket *sock, int backlog)
 490 {
 491         struct sock *sk = sock->sk;
 492         int rc = -EOPNOTSUPP;
 493
 494         lock_sock(sk);
 495         if (sk->sk_state != TCP_LISTEN) {
 496                 memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 497                 sk->sk_max_ack_backlog = backlog;
 498                 sk->sk_state           = TCP_LISTEN;
 499                 rc = 0;
 500         }
 501         release_sock(sk);
 502
 503         return rc;
 504 }
 505
 506 static struct proto x25_proto = {
 507         .name     = "X25",
 508         .owner    = THIS_MODULE,
 509         .obj_size = sizeof(struct x25_sock),
 510 };
 511
 512 static struct sock *x25_alloc_socket(struct net *net, int kern)
 513 {
 514         struct x25_sock *x25;
 515         struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 516
 517         if (!sk)
 518                 goto out;
 519
 520         sock_init_data(NULL, sk);
 521
 522         x25 = x25_sk(sk);
 523         skb_queue_head_init(&x25->ack_queue);
 524         skb_queue_head_init(&x25->fragment_queue);
 525         skb_queue_head_init(&x25->interrupt_in_queue);
 526         skb_queue_head_init(&x25->interrupt_out_queue);
 527 out:
 528         return sk;
 529 }
 530
 531 static int x25_create(struct net *net, struct socket *sock, int protocol,
 532                       int kern)
 533 {
 534         struct sock *sk;
 535         struct x25_sock *x25;
 536         int rc = -EAFNOSUPPORT;
 537
 538         if (!net_eq(net, &init_net))
 539                 goto out;
 540
 541         rc = -ESOCKTNOSUPPORT;
 542         if (sock->type != SOCK_SEQPACKET)
 543                 goto out;
 544
 545         rc = -EINVAL;
 546         if (protocol)
 547                 goto out;
 548
 549         rc = -ENOBUFS;
 550         if ((sk = x25_alloc_socket(net, kern)) == NULL)
 551                 goto out;
 552
 553         x25 = x25_sk(sk);
 554
 555         sock_init_data(sock, sk);
 556
 557         x25_init_timers(sk);
 558
 559         sock->ops    = &x25_proto_ops;
 560         sk->sk_protocol = protocol;
 561         sk->sk_backlog_rcv = x25_backlog_rcv;
 562
 563         x25->t21   = sysctl_x25_call_request_timeout;
 564         x25->t22   = sysctl_x25_reset_request_timeout;
 565         x25->t23   = sysctl_x25_clear_request_timeout;
 566         x25->t2    = sysctl_x25_ack_holdback_timeout;
 567         x25->state = X25_STATE_0;
 568         x25->cudmatchlength = 0;
 569         set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);     /* normally no cud  */
 570                                                         /* on call accept   */
 571
 572         x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 573         x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 574         x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 575         x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 576         x25->facilities.throughput  = 0;        /* by default don't negotiate
 577                                                    throughput */
 578         x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 579         x25->dte_facilities.calling_len = 0;
 580         x25->dte_facilities.called_len = 0;
 581         memset(x25->dte_facilities.called_ae, '\0',
 582                         sizeof(x25->dte_facilities.called_ae));
 583         memset(x25->dte_facilities.calling_ae, '\0',
 584                         sizeof(x25->dte_facilities.calling_ae));
 585
 586         rc = 0;
 587 out:
 588         return rc;
 589 }
 590
 591 static struct sock *x25_make_new(struct sock *osk)
 592 {
 593         struct sock *sk = NULL;
 594         struct x25_sock *x25, *ox25;
 595
 596         if (osk->sk_type != SOCK_SEQPACKET)
 597                 goto out;
 598
 599         if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 600                 goto out;
 601
 602         x25 = x25_sk(sk);
 603
 604         sk->sk_type        = osk->sk_type;
 605         sk->sk_priority    = osk->sk_priority;
 606         sk->sk_protocol    = osk->sk_protocol;
 607         sk->sk_rcvbuf      = osk->sk_rcvbuf;
 608         sk->sk_sndbuf      = osk->sk_sndbuf;
 609         sk->sk_state       = TCP_ESTABLISHED;
 610         sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 611         sock_copy_flags(sk, osk);
 612
 613         ox25 = x25_sk(osk);
 614         x25->t21        = ox25->t21;
 615         x25->t22        = ox25->t22;
 616         x25->t23        = ox25->t23;
 617         x25->t2         = ox25->t2;
 618         x25->flags      = ox25->flags;
 619         x25->facilities = ox25->facilities;
 620         x25->dte_facilities = ox25->dte_facilities;
 621         x25->cudmatchlength = ox25->cudmatchlength;
 622
 623         clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 624         x25_init_timers(sk);
 625 out:
 626         return sk;
 627 }
 628
 629 static int x25_release(struct socket *sock)
 630 {
 631         struct sock *sk = sock->sk;
 632         struct x25_sock *x25;
 633
 634         if (!sk)
 635                 return 0;
 636
 637         x25 = x25_sk(sk);
 638
 639         sock_hold(sk);
 640         lock_sock(sk);
 641         switch (x25->state) {
 642
 643                 case X25_STATE_0:
 644                 case X25_STATE_2:
 645                         x25_disconnect(sk, 0, 0, 0);
 646                         __x25_destroy_socket(sk);
 647                         goto out;
 648
 649                 case X25_STATE_1:
 650                 case X25_STATE_3:
 651                 case X25_STATE_4:
 652                         x25_clear_queues(sk);
 653                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 654                         x25_start_t23timer(sk);
 655                         x25->state = X25_STATE_2;
 656                         sk->sk_state    = TCP_CLOSE;
 657                         sk->sk_shutdown |= SEND_SHUTDOWN;
 658                         sk->sk_state_change(sk);
 659                         sock_set_flag(sk, SOCK_DEAD);
 660                         sock_set_flag(sk, SOCK_DESTROY);
 661                         break;
 662         }
 663
 664         sock_orphan(sk);
 665 out:
 666         release_sock(sk);
 667         sock_put(sk);
 668         return 0;
 669 }
 670
 671 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 672 {
 673         struct sock *sk = sock->sk;
 674         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 675         int len, i, rc = 0;
 676
 677         if (addr_len != sizeof(struct sockaddr_x25) ||
 678             addr->sx25_family != AF_X25) {
 679                 rc = -EINVAL;
 680                 goto out;
 681         }
 682
 683         /* check for the null_x25_address */
 684         if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
 685
 686                 len = strlen(addr->sx25_addr.x25_addr);
 687                 for (i = 0; i < len; i++) {
 688                         if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 689                                 rc = -EINVAL;
 690                                 goto out;
 691                         }
 692                 }
 693         }
 694
 695         lock_sock(sk);
 696         if (sock_flag(sk, SOCK_ZAPPED)) {
 697                 x25_sk(sk)->source_addr = addr->sx25_addr;
 698                 x25_insert_socket(sk);
 699                 sock_reset_flag(sk, SOCK_ZAPPED);
 700         } else {
 701                 rc = -EINVAL;
 702         }
 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                 read_lock_bh(&x25_list_lock);
 820                 x25_neigh_put(x25->neighbour);
 821                 x25->neighbour = NULL;
 822                 read_unlock_bh(&x25_list_lock);
 823                 x25->state = X25_STATE_0;
 824         }
 825 out_put_route:
 826         x25_route_put(rt);
 827 out:
 828         release_sock(sk);
 829         return rc;
 830 }
 831
 832 static int x25_wait_for_data(struct sock *sk, long timeout)
 833 {
 834         DECLARE_WAITQUEUE(wait, current);
 835         int rc = 0;
 836
 837         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 838         for (;;) {
 839                 __set_current_state(TASK_INTERRUPTIBLE);
 840                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 841                         break;
 842                 rc = -ERESTARTSYS;
 843                 if (signal_pending(current))
 844                         break;
 845                 rc = -EAGAIN;
 846                 if (!timeout)
 847                         break;
 848                 rc = 0;
 849                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 850                         release_sock(sk);
 851                         timeout = schedule_timeout(timeout);
 852                         lock_sock(sk);
 853                 } else
 854                         break;
 855         }
 856         __set_current_state(TASK_RUNNING);
 857         remove_wait_queue(sk_sleep(sk), &wait);
 858         return rc;
 859 }
 860
 861 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 862                       bool kern)
 863 {
 864         struct sock *sk = sock->sk;
 865         struct sock *newsk;
 866         struct sk_buff *skb;
 867         int rc = -EINVAL;
 868
 869         if (!sk)
 870                 goto out;
 871
 872         rc = -EOPNOTSUPP;
 873         if (sk->sk_type != SOCK_SEQPACKET)
 874                 goto out;
 875
 876         lock_sock(sk);
 877         rc = -EINVAL;
 878         if (sk->sk_state != TCP_LISTEN)
 879                 goto out2;
 880
 881         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 882         if (rc)
 883                 goto out2;
 884         skb = skb_dequeue(&sk->sk_receive_queue);
 885         rc = -EINVAL;
 886         if (!skb->sk)
 887                 goto out2;
 888         newsk            = skb->sk;
 889         sock_graft(newsk, newsock);
 890
 891         /* Now attach up the new socket */
 892         skb->sk = NULL;
 893         kfree_skb(skb);
 894         sk->sk_ack_backlog--;
 895         newsock->state = SS_CONNECTED;
 896         rc = 0;
 897 out2:
 898         release_sock(sk);
 899 out:
 900         return rc;
 901 }
 902
 903 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 904                        int peer)
 905 {
 906         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 907         struct sock *sk = sock->sk;
 908         struct x25_sock *x25 = x25_sk(sk);
 909         int rc = 0;
 910
 911         if (peer) {
 912                 if (sk->sk_state != TCP_ESTABLISHED) {
 913                         rc = -ENOTCONN;
 914                         goto out;
 915                 }
 916                 sx25->sx25_addr = x25->dest_addr;
 917         } else
 918                 sx25->sx25_addr = x25->source_addr;
 919
 920         sx25->sx25_family = AF_X25;
 921         rc = sizeof(*sx25);
 922
 923 out:
 924         return rc;
 925 }
 926
 927 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 928                         unsigned int lci)
 929 {
 930         struct sock *sk;
 931         struct sock *make;
 932         struct x25_sock *makex25;
 933         struct x25_address source_addr, dest_addr;
 934         struct x25_facilities facilities;
 935         struct x25_dte_facilities dte_facilities;
 936         int len, addr_len, rc;
 937
 938         /*
 939          *      Remove the LCI and frame type.
 940          */
 941         skb_pull(skb, X25_STD_MIN_LEN);
 942
 943         /*
 944          *      Extract the X.25 addresses and convert them to ASCII strings,
 945          *      and remove them.
 946          *
 947          *      Address block is mandatory in call request packets
 948          */
 949         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 950         if (addr_len <= 0)
 951                 goto out_clear_request;
 952         skb_pull(skb, addr_len);
 953
 954         /*
 955          *      Get the length of the facilities, skip past them for the moment
 956          *      get the call user data because this is needed to determine
 957          *      the correct listener
 958          *
 959          *      Facilities length is mandatory in call request packets
 960          */
 961         if (!pskb_may_pull(skb, 1))
 962                 goto out_clear_request;
 963         len = skb->data[0] + 1;
 964         if (!pskb_may_pull(skb, len))
 965                 goto out_clear_request;
 966         skb_pull(skb,len);
 967
 968         /*
 969          *      Ensure that the amount of call user data is valid.
 970          */
 971         if (skb->len > X25_MAX_CUD_LEN)
 972                 goto out_clear_request;
 973
 974         /*
 975          *      Get all the call user data so it can be used in
 976          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 977          */
 978         if (!pskb_may_pull(skb, skb->len))
 979                 goto out_clear_request;
 980
 981         /*
 982          *      Find a listener for the particular address/cud pair.
 983          */
 984         sk = x25_find_listener(&source_addr,skb);
 985         skb_push(skb,len);
 986
 987         if (sk != NULL && sk_acceptq_is_full(sk)) {
 988                 goto out_sock_put;
 989         }
 990
 991         /*
 992          *      We dont have any listeners for this incoming call.
 993          *      Try forwarding it.
 994          */
 995         if (sk == NULL) {
 996                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
 997                 if (sysctl_x25_forward &&
 998                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
 999                 {
1000                         /* Call was forwarded, dont process it any more */
1001                         kfree_skb(skb);
1002                         rc = 1;
1003                         goto out;
1004                 } else {
1005                         /* No listeners, can't forward, clear the call */
1006                         goto out_clear_request;
1007                 }
1008         }
1009
1010         /*
1011          *      Try to reach a compromise on the requested facilities.
1012          */
1013         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1014         if (len == -1)
1015                 goto out_sock_put;
1016
1017         /*
1018          * current neighbour/link might impose additional limits
1019          * on certain facilties
1020          */
1021
1022         x25_limit_facilities(&facilities, nb);
1023
1024         /*
1025          *      Try to create a new socket.
1026          */
1027         make = x25_make_new(sk);
1028         if (!make)
1029                 goto out_sock_put;
1030
1031         /*
1032          *      Remove the facilities
1033          */
1034         skb_pull(skb, len);
1035
1036         skb->sk     = make;
1037         make->sk_state = TCP_ESTABLISHED;
1038
1039         makex25 = x25_sk(make);
1040         makex25->lci           = lci;
1041         makex25->dest_addr     = dest_addr;
1042         makex25->source_addr   = source_addr;
1043         makex25->neighbour     = nb;
1044         makex25->facilities    = facilities;
1045         makex25->dte_facilities= dte_facilities;
1046         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1047         /* ensure no reverse facil on accept */
1048         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1049         /* ensure no calling address extension on accept */
1050         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1051         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1052
1053         /* Normally all calls are accepted immediately */
1054         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1055                 x25_write_internal(make, X25_CALL_ACCEPTED);
1056                 makex25->state = X25_STATE_3;
1057         }
1058
1059         /*
1060          *      Incoming Call User Data.
1061          */
1062         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1063         makex25->calluserdata.cudlength = skb->len;
1064
1065         sk->sk_ack_backlog++;
1066
1067         x25_insert_socket(make);
1068
1069         skb_queue_head(&sk->sk_receive_queue, skb);
1070
1071         x25_start_heartbeat(make);
1072
1073         if (!sock_flag(sk, SOCK_DEAD))
1074                 sk->sk_data_ready(sk);
1075         rc = 1;
1076         sock_put(sk);
1077 out:
1078         return rc;
1079 out_sock_put:
1080         sock_put(sk);
1081 out_clear_request:
1082         rc = 0;
1083         x25_transmit_clear_request(nb, lci, 0x01);
1084         goto out;
1085 }
1086
1087 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1088 {
1089         struct sock *sk = sock->sk;
1090         struct x25_sock *x25 = x25_sk(sk);
1091         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1092         struct sockaddr_x25 sx25;
1093         struct sk_buff *skb;
1094         unsigned char *asmptr;
1095         int noblock = msg->msg_flags & MSG_DONTWAIT;
1096         size_t size;
1097         int qbit = 0, rc = -EINVAL;
1098
1099         lock_sock(sk);
1100         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1101                 goto out;
1102
1103         /* we currently don't support segmented records at the user interface */
1104         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1105                 goto out;
1106
1107         rc = -EADDRNOTAVAIL;
1108         if (sock_flag(sk, SOCK_ZAPPED))
1109                 goto out;
1110
1111         rc = -EPIPE;
1112         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1113                 send_sig(SIGPIPE, current, 0);
1114                 goto out;
1115         }
1116
1117         rc = -ENETUNREACH;
1118         if (!x25->neighbour)
1119                 goto out;
1120
1121         if (usx25) {
1122                 rc = -EINVAL;
1123                 if (msg->msg_namelen < sizeof(sx25))
1124                         goto out;
1125                 memcpy(&sx25, usx25, sizeof(sx25));
1126                 rc = -EISCONN;
1127                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1128                         goto out;
1129                 rc = -EINVAL;
1130                 if (sx25.sx25_family != AF_X25)
1131                         goto out;
1132         } else {
1133                 /*
1134                  *      FIXME 1003.1g - if the socket is like this because
1135                  *      it has become closed (not started closed) we ought
1136                  *      to SIGPIPE, EPIPE;
1137                  */
1138                 rc = -ENOTCONN;
1139                 if (sk->sk_state != TCP_ESTABLISHED)
1140                         goto out;
1141
1142                 sx25.sx25_family = AF_X25;
1143                 sx25.sx25_addr   = x25->dest_addr;
1144         }
1145
1146         /* Sanity check the packet size */
1147         if (len > 65535) {
1148                 rc = -EMSGSIZE;
1149                 goto out;
1150         }
1151
1152         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1153
1154         /* Build a packet */
1155         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1156
1157         if ((msg->msg_flags & MSG_OOB) && len > 32)
1158                 len = 32;
1159
1160         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1161
1162         release_sock(sk);
1163         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1164         lock_sock(sk);
1165         if (!skb)
1166                 goto out;
1167         X25_SKB_CB(skb)->flags = msg->msg_flags;
1168
1169         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1170
1171         /*
1172          *      Put the data on the end
1173          */
1174         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1175
1176         skb_reset_transport_header(skb);
1177         skb_put(skb, len);
1178
1179         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1180         if (rc)
1181                 goto out_kfree_skb;
1182
1183         /*
1184          *      If the Q BIT Include socket option is in force, the first
1185          *      byte of the user data is the logical value of the Q Bit.
1186          */
1187         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1188                 if (!pskb_may_pull(skb, 1))
1189                         goto out_kfree_skb;
1190
1191                 qbit = skb->data[0];
1192                 skb_pull(skb, 1);
1193         }
1194
1195         /*
1196          *      Push down the X.25 header
1197          */
1198         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1199
1200         if (msg->msg_flags & MSG_OOB) {
1201                 if (x25->neighbour->extended) {
1202                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1203                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1204                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1205                         *asmptr++ = X25_INTERRUPT;
1206                 } else {
1207                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1208                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1209                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1210                         *asmptr++ = X25_INTERRUPT;
1211                 }
1212         } else {
1213                 if (x25->neighbour->extended) {
1214                         /* Build an Extended X.25 header */
1215                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1216                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1217                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1218                         *asmptr++ = X25_DATA;
1219                         *asmptr++ = X25_DATA;
1220                 } else {
1221                         /* Build an Standard X.25 header */
1222                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1223                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1224                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1225                         *asmptr++ = X25_DATA;
1226                 }
1227
1228                 if (qbit)
1229                         skb->data[0] |= X25_Q_BIT;
1230         }
1231
1232         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1233         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1234
1235         rc = -ENOTCONN;
1236         if (sk->sk_state != TCP_ESTABLISHED)
1237                 goto out_kfree_skb;
1238
1239         if (msg->msg_flags & MSG_OOB)
1240                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1241         else {
1242                 rc = x25_output(sk, skb);
1243                 len = rc;
1244                 if (rc < 0)
1245                         kfree_skb(skb);
1246                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1247                         len++;
1248         }
1249
1250         x25_kick(sk);
1251         rc = len;
1252 out:
1253         release_sock(sk);
1254         return rc;
1255 out_kfree_skb:
1256         kfree_skb(skb);
1257         goto out;
1258 }
1259
1260
1261 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1262                        int flags)
1263 {
1264         struct sock *sk = sock->sk;
1265         struct x25_sock *x25 = x25_sk(sk);
1266         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1267         size_t copied;
1268         int qbit, header_len;
1269         struct sk_buff *skb;
1270         unsigned char *asmptr;
1271         int rc = -ENOTCONN;
1272
1273         lock_sock(sk);
1274
1275         if (x25->neighbour == NULL)
1276                 goto out;
1277
1278         header_len = x25->neighbour->extended ?
1279                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1280
1281         /*
1282          * This works for seqpacket too. The receiver has ordered the queue for
1283          * us! We do one quick check first though
1284          */
1285         if (sk->sk_state != TCP_ESTABLISHED)
1286                 goto out;
1287
1288         if (flags & MSG_OOB) {
1289                 rc = -EINVAL;
1290                 if (sock_flag(sk, SOCK_URGINLINE) ||
1291                     !skb_peek(&x25->interrupt_in_queue))
1292                         goto out;
1293
1294                 skb = skb_dequeue(&x25->interrupt_in_queue);
1295
1296                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1297                         goto out_free_dgram;
1298
1299                 skb_pull(skb, X25_STD_MIN_LEN);
1300
1301                 /*
1302                  *      No Q bit information on Interrupt data.
1303                  */
1304                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1305                         asmptr  = skb_push(skb, 1);
1306                         *asmptr = 0x00;
1307                 }
1308
1309                 msg->msg_flags |= MSG_OOB;
1310         } else {
1311                 /* Now we can treat all alike */
1312                 release_sock(sk);
1313                 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1314                                         flags & MSG_DONTWAIT, &rc);
1315                 lock_sock(sk);
1316                 if (!skb)
1317                         goto out;
1318
1319                 if (!pskb_may_pull(skb, header_len))
1320                         goto out_free_dgram;
1321
1322                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1323
1324                 skb_pull(skb, header_len);
1325
1326                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1327                         asmptr  = skb_push(skb, 1);
1328                         *asmptr = qbit;
1329                 }
1330         }
1331
1332         skb_reset_transport_header(skb);
1333         copied = skb->len;
1334
1335         if (copied > size) {
1336                 copied = size;
1337                 msg->msg_flags |= MSG_TRUNC;
1338         }
1339
1340         /* Currently, each datagram always contains a complete record */
1341         msg->msg_flags |= MSG_EOR;
1342
1343         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1344         if (rc)
1345                 goto out_free_dgram;
1346
1347         if (sx25) {
1348                 sx25->sx25_family = AF_X25;
1349                 sx25->sx25_addr   = x25->dest_addr;
1350                 msg->msg_namelen = sizeof(*sx25);
1351         }
1352
1353         x25_check_rbuf(sk);
1354         rc = copied;
1355 out_free_dgram:
1356         skb_free_datagram(sk, skb);
1357 out:
1358         release_sock(sk);
1359         return rc;
1360 }
1361
1362
1363 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1364 {
1365         struct sock *sk = sock->sk;
1366         struct x25_sock *x25 = x25_sk(sk);
1367         void __user *argp = (void __user *)arg;
1368         int rc;
1369
1370         switch (cmd) {
1371         case TIOCOUTQ: {
1372                 int amount;
1373
1374                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1375                 if (amount < 0)
1376                         amount = 0;
1377                 rc = put_user(amount, (unsigned int __user *)argp);
1378                 break;
1379         }
1380
1381         case TIOCINQ: {
1382                 struct sk_buff *skb;
1383                 int amount = 0;
1384                 /*
1385                  * These two are safe on a single CPU system as
1386                  * only user tasks fiddle here
1387                  */
1388                 lock_sock(sk);
1389                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1390                         amount = skb->len;
1391                 release_sock(sk);
1392                 rc = put_user(amount, (unsigned int __user *)argp);
1393                 break;
1394         }
1395
1396         case SIOCGIFADDR:
1397         case SIOCSIFADDR:
1398         case SIOCGIFDSTADDR:
1399         case SIOCSIFDSTADDR:
1400         case SIOCGIFBRDADDR:
1401         case SIOCSIFBRDADDR:
1402         case SIOCGIFNETMASK:
1403         case SIOCSIFNETMASK:
1404         case SIOCGIFMETRIC:
1405         case SIOCSIFMETRIC:
1406                 rc = -EINVAL;
1407                 break;
1408         case SIOCADDRT:
1409         case SIOCDELRT:
1410                 rc = -EPERM;
1411                 if (!capable(CAP_NET_ADMIN))
1412                         break;
1413                 rc = x25_route_ioctl(cmd, argp);
1414                 break;
1415         case SIOCX25GSUBSCRIP:
1416                 rc = x25_subscr_ioctl(cmd, argp);
1417                 break;
1418         case SIOCX25SSUBSCRIP:
1419                 rc = -EPERM;
1420                 if (!capable(CAP_NET_ADMIN))
1421                         break;
1422                 rc = x25_subscr_ioctl(cmd, argp);
1423                 break;
1424         case SIOCX25GFACILITIES: {
1425                 lock_sock(sk);
1426                 rc = copy_to_user(argp, &x25->facilities,
1427                                   sizeof(x25->facilities))
1428                         ? -EFAULT : 0;
1429                 release_sock(sk);
1430                 break;
1431         }
1432
1433         case SIOCX25SFACILITIES: {
1434                 struct x25_facilities facilities;
1435                 rc = -EFAULT;
1436                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1437                         break;
1438                 rc = -EINVAL;
1439                 lock_sock(sk);
1440                 if (sk->sk_state != TCP_LISTEN &&
1441                     sk->sk_state != TCP_CLOSE)
1442                         goto out_fac_release;
1443                 if (facilities.pacsize_in < X25_PS16 ||
1444                     facilities.pacsize_in > X25_PS4096)
1445                         goto out_fac_release;
1446                 if (facilities.pacsize_out < X25_PS16 ||
1447                     facilities.pacsize_out > X25_PS4096)
1448                         goto out_fac_release;
1449                 if (facilities.winsize_in < 1 ||
1450                     facilities.winsize_in > 127)
1451                         goto out_fac_release;
1452                 if (facilities.throughput) {
1453                         int out = facilities.throughput & 0xf0;
1454                         int in  = facilities.throughput & 0x0f;
1455                         if (!out)
1456                                 facilities.throughput |=
1457                                         X25_DEFAULT_THROUGHPUT << 4;
1458                         else if (out < 0x30 || out > 0xD0)
1459                                 goto out_fac_release;
1460                         if (!in)
1461                                 facilities.throughput |=
1462                                         X25_DEFAULT_THROUGHPUT;
1463                         else if (in < 0x03 || in > 0x0D)
1464                                 goto out_fac_release;
1465                 }
1466                 if (facilities.reverse &&
1467                     (facilities.reverse & 0x81) != 0x81)
1468                         goto out_fac_release;
1469                 x25->facilities = facilities;
1470                 rc = 0;
1471 out_fac_release:
1472                 release_sock(sk);
1473                 break;
1474         }
1475
1476         case SIOCX25GDTEFACILITIES: {
1477                 lock_sock(sk);
1478                 rc = copy_to_user(argp, &x25->dte_facilities,
1479                                   sizeof(x25->dte_facilities));
1480                 release_sock(sk);
1481                 if (rc)
1482                         rc = -EFAULT;
1483                 break;
1484         }
1485
1486         case SIOCX25SDTEFACILITIES: {
1487                 struct x25_dte_facilities dtefacs;
1488                 rc = -EFAULT;
1489                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1490                         break;
1491                 rc = -EINVAL;
1492                 lock_sock(sk);
1493                 if (sk->sk_state != TCP_LISTEN &&
1494                     sk->sk_state != TCP_CLOSE)
1495                         goto out_dtefac_release;
1496                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1497                         goto out_dtefac_release;
1498                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1499                         goto out_dtefac_release;
1500                 x25->dte_facilities = dtefacs;
1501                 rc = 0;
1502 out_dtefac_release:
1503                 release_sock(sk);
1504                 break;
1505         }
1506
1507         case SIOCX25GCALLUSERDATA: {
1508                 lock_sock(sk);
1509                 rc = copy_to_user(argp, &x25->calluserdata,
1510                                   sizeof(x25->calluserdata))
1511                         ? -EFAULT : 0;
1512                 release_sock(sk);
1513                 break;
1514         }
1515
1516         case SIOCX25SCALLUSERDATA: {
1517                 struct x25_calluserdata calluserdata;
1518
1519                 rc = -EFAULT;
1520                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1521                         break;
1522                 rc = -EINVAL;
1523                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1524                         break;
1525                 lock_sock(sk);
1526                 x25->calluserdata = calluserdata;
1527                 release_sock(sk);
1528                 rc = 0;
1529                 break;
1530         }
1531
1532         case SIOCX25GCAUSEDIAG: {
1533                 lock_sock(sk);
1534                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1535                         ? -EFAULT : 0;
1536                 release_sock(sk);
1537                 break;
1538         }
1539
1540         case SIOCX25SCAUSEDIAG: {
1541                 struct x25_causediag causediag;
1542                 rc = -EFAULT;
1543                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1544                         break;
1545                 lock_sock(sk);
1546                 x25->causediag = causediag;
1547                 release_sock(sk);
1548                 rc = 0;
1549                 break;
1550
1551         }
1552
1553         case SIOCX25SCUDMATCHLEN: {
1554                 struct x25_subaddr sub_addr;
1555                 rc = -EINVAL;
1556                 lock_sock(sk);
1557                 if(sk->sk_state != TCP_CLOSE)
1558                         goto out_cud_release;
1559                 rc = -EFAULT;
1560                 if (copy_from_user(&sub_addr, argp,
1561                                    sizeof(sub_addr)))
1562                         goto out_cud_release;
1563                 rc = -EINVAL;
1564                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1565                         goto out_cud_release;
1566                 x25->cudmatchlength = sub_addr.cudmatchlength;
1567                 rc = 0;
1568 out_cud_release:
1569                 release_sock(sk);
1570                 break;
1571         }
1572
1573         case SIOCX25CALLACCPTAPPRV: {
1574                 rc = -EINVAL;
1575                 lock_sock(sk);
1576                 if (sk->sk_state == TCP_CLOSE) {
1577                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1578                         rc = 0;
1579                 }
1580                 release_sock(sk);
1581                 break;
1582         }
1583
1584         case SIOCX25SENDCALLACCPT:  {
1585                 rc = -EINVAL;
1586                 lock_sock(sk);
1587                 if (sk->sk_state != TCP_ESTABLISHED)
1588                         goto out_sendcallaccpt_release;
1589                 /* must call accptapprv above */
1590                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1591                         goto out_sendcallaccpt_release;
1592                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1593                 x25->state = X25_STATE_3;
1594                 rc = 0;
1595 out_sendcallaccpt_release:
1596                 release_sock(sk);
1597                 break;
1598         }
1599
1600         default:
1601                 rc = -ENOIOCTLCMD;
1602                 break;
1603         }
1604
1605         return rc;
1606 }
1607
1608 static const struct net_proto_family x25_family_ops = {
1609         .family =       AF_X25,
1610         .create =       x25_create,
1611         .owner  =       THIS_MODULE,
1612 };
1613
1614 #ifdef CONFIG_COMPAT
1615 static int compat_x25_subscr_ioctl(unsigned int cmd,
1616                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1617 {
1618         struct compat_x25_subscrip_struct x25_subscr;
1619         struct x25_neigh *nb;
1620         struct net_device *dev;
1621         int rc = -EINVAL;
1622
1623         rc = -EFAULT;
1624         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1625                 goto out;
1626
1627         rc = -EINVAL;
1628         dev = x25_dev_get(x25_subscr.device);
1629         if (dev == NULL)
1630                 goto out;
1631
1632         nb = x25_get_neigh(dev);
1633         if (nb == NULL)
1634                 goto out_dev_put;
1635
1636         dev_put(dev);
1637
1638         if (cmd == SIOCX25GSUBSCRIP) {
1639                 read_lock_bh(&x25_neigh_list_lock);
1640                 x25_subscr.extended = nb->extended;
1641                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1642                 read_unlock_bh(&x25_neigh_list_lock);
1643                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1644                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1645         } else {
1646                 rc = -EINVAL;
1647                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1648                         rc = 0;
1649                         write_lock_bh(&x25_neigh_list_lock);
1650                         nb->extended = x25_subscr.extended;
1651                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1652                         write_unlock_bh(&x25_neigh_list_lock);
1653                 }
1654         }
1655         x25_neigh_put(nb);
1656 out:
1657         return rc;
1658 out_dev_put:
1659         dev_put(dev);
1660         goto out;
1661 }
1662
1663 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1664                                 unsigned long arg)
1665 {
1666         void __user *argp = compat_ptr(arg);
1667         int rc = -ENOIOCTLCMD;
1668
1669         switch(cmd) {
1670         case TIOCOUTQ:
1671         case TIOCINQ:
1672                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1673                 break;
1674         case SIOCGIFADDR:
1675         case SIOCSIFADDR:
1676         case SIOCGIFDSTADDR:
1677         case SIOCSIFDSTADDR:
1678         case SIOCGIFBRDADDR:
1679         case SIOCSIFBRDADDR:
1680         case SIOCGIFNETMASK:
1681         case SIOCSIFNETMASK:
1682         case SIOCGIFMETRIC:
1683         case SIOCSIFMETRIC:
1684                 rc = -EINVAL;
1685                 break;
1686         case SIOCADDRT:
1687         case SIOCDELRT:
1688                 rc = -EPERM;
1689                 if (!capable(CAP_NET_ADMIN))
1690                         break;
1691                 rc = x25_route_ioctl(cmd, argp);
1692                 break;
1693         case SIOCX25GSUBSCRIP:
1694                 rc = compat_x25_subscr_ioctl(cmd, argp);
1695                 break;
1696         case SIOCX25SSUBSCRIP:
1697                 rc = -EPERM;
1698                 if (!capable(CAP_NET_ADMIN))
1699                         break;
1700                 rc = compat_x25_subscr_ioctl(cmd, argp);
1701                 break;
1702         case SIOCX25GFACILITIES:
1703         case SIOCX25SFACILITIES:
1704         case SIOCX25GDTEFACILITIES:
1705         case SIOCX25SDTEFACILITIES:
1706         case SIOCX25GCALLUSERDATA:
1707         case SIOCX25SCALLUSERDATA:
1708         case SIOCX25GCAUSEDIAG:
1709         case SIOCX25SCAUSEDIAG:
1710         case SIOCX25SCUDMATCHLEN:
1711         case SIOCX25CALLACCPTAPPRV:
1712         case SIOCX25SENDCALLACCPT:
1713                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1714                 break;
1715         default:
1716                 rc = -ENOIOCTLCMD;
1717                 break;
1718         }
1719         return rc;
1720 }
1721 #endif
1722
1723 static const struct proto_ops x25_proto_ops = {
1724         .family =       AF_X25,
1725         .owner =        THIS_MODULE,
1726         .release =      x25_release,
1727         .bind =         x25_bind,
1728         .connect =      x25_connect,
1729         .socketpair =   sock_no_socketpair,
1730         .accept =       x25_accept,
1731         .getname =      x25_getname,
1732         .poll =         datagram_poll,
1733         .ioctl =        x25_ioctl,
1734 #ifdef CONFIG_COMPAT
1735         .compat_ioctl = compat_x25_ioctl,
1736 #endif
1737         .gettstamp =    sock_gettstamp,
1738         .listen =       x25_listen,
1739         .shutdown =     sock_no_shutdown,
1740         .setsockopt =   x25_setsockopt,
1741         .getsockopt =   x25_getsockopt,
1742         .sendmsg =      x25_sendmsg,
1743         .recvmsg =      x25_recvmsg,
1744         .mmap =         sock_no_mmap,
1745         .sendpage =     sock_no_sendpage,
1746 };
1747
1748 static struct packet_type x25_packet_type __read_mostly = {
1749         .type = cpu_to_be16(ETH_P_X25),
1750         .func = x25_lapb_receive_frame,
1751 };
1752
1753 static struct notifier_block x25_dev_notifier = {
1754         .notifier_call = x25_device_event,
1755 };
1756
1757 void x25_kill_by_neigh(struct x25_neigh *nb)
1758 {
1759         struct sock *s;
1760
1761         write_lock_bh(&x25_list_lock);
1762
1763         sk_for_each(s, &x25_list)
1764                 if (x25_sk(s)->neighbour == nb)
1765                         x25_disconnect(s, ENETUNREACH, 0, 0);
1766
1767         write_unlock_bh(&x25_list_lock);
1768
1769         /* Remove any related forwards */
1770         x25_clear_forward_by_dev(nb->dev);
1771 }
1772
1773 static int __init x25_init(void)
1774 {
1775         int rc;
1776
1777         rc = proto_register(&x25_proto, 0);
1778         if (rc)
1779                 goto out;
1780
1781         rc = sock_register(&x25_family_ops);
1782         if (rc)
1783                 goto out_proto;
1784
1785         dev_add_pack(&x25_packet_type);
1786
1787         rc = register_netdevice_notifier(&x25_dev_notifier);
1788         if (rc)
1789                 goto out_sock;
1790
1791         rc = x25_register_sysctl();
1792         if (rc)
1793                 goto out_dev;
1794
1795         rc = x25_proc_init();
1796         if (rc)
1797                 goto out_sysctl;
1798
1799         pr_info("Linux Version 0.2\n");
1800
1801 out:
1802         return rc;
1803 out_sysctl:
1804         x25_unregister_sysctl();
1805 out_dev:
1806         unregister_netdevice_notifier(&x25_dev_notifier);
1807 out_sock:
1808         dev_remove_pack(&x25_packet_type);
1809         sock_unregister(AF_X25);
1810 out_proto:
1811         proto_unregister(&x25_proto);
1812         goto out;
1813 }
1814 module_init(x25_init);
1815
1816 static void __exit x25_exit(void)
1817 {
1818         x25_proc_exit();
1819         x25_link_free();
1820         x25_route_free();
1821
1822         x25_unregister_sysctl();
1823
1824         unregister_netdevice_notifier(&x25_dev_notifier);
1825
1826         dev_remove_pack(&x25_packet_type);
1827
1828         sock_unregister(AF_X25);
1829         proto_unregister(&x25_proto);
1830 }
1831 module_exit(x25_exit);
1832
1833 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1834 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1835 MODULE_LICENSE("GPL");
1836 MODULE_ALIAS_NETPROTO(PF_X25);