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                           sockptr_t 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 (copy_from_sockptr(&opt, optval, sizeof(int)))
 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                 case X25_STATE_5:
 664                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 665                         x25_disconnect(sk, 0, 0, 0);
 666                         __x25_destroy_socket(sk);
 667                         goto out;
 668         }
 669
 670         sock_orphan(sk);
 671 out:
 672         release_sock(sk);
 673         sock_put(sk);
 674         return 0;
 675 }
 676
 677 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 678 {
 679         struct sock *sk = sock->sk;
 680         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 681         int len, i, rc = 0;
 682
 683         if (addr_len != sizeof(struct sockaddr_x25) ||
 684             addr->sx25_family != AF_X25 ||
 685             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) {
 686                 rc = -EINVAL;
 687                 goto out;
 688         }
 689
 690         /* check for the null_x25_address */
 691         if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
 692
 693                 len = strlen(addr->sx25_addr.x25_addr);
 694                 for (i = 0; i < len; i++) {
 695                         if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 696                                 rc = -EINVAL;
 697                                 goto out;
 698                         }
 699                 }
 700         }
 701
 702         lock_sock(sk);
 703         if (sock_flag(sk, SOCK_ZAPPED)) {
 704                 x25_sk(sk)->source_addr = addr->sx25_addr;
 705                 x25_insert_socket(sk);
 706                 sock_reset_flag(sk, SOCK_ZAPPED);
 707         } else {
 708                 rc = -EINVAL;
 709         }
 710         release_sock(sk);
 711         SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
 712 out:
 713         return rc;
 714 }
 715
 716 static int x25_wait_for_connection_establishment(struct sock *sk)
 717 {
 718         DECLARE_WAITQUEUE(wait, current);
 719         int rc;
 720
 721         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 722         for (;;) {
 723                 __set_current_state(TASK_INTERRUPTIBLE);
 724                 rc = -ERESTARTSYS;
 725                 if (signal_pending(current))
 726                         break;
 727                 rc = sock_error(sk);
 728                 if (rc) {
 729                         sk->sk_socket->state = SS_UNCONNECTED;
 730                         break;
 731                 }
 732                 rc = 0;
 733                 if (sk->sk_state != TCP_ESTABLISHED) {
 734                         release_sock(sk);
 735                         schedule();
 736                         lock_sock(sk);
 737                 } else
 738                         break;
 739         }
 740         __set_current_state(TASK_RUNNING);
 741         remove_wait_queue(sk_sleep(sk), &wait);
 742         return rc;
 743 }
 744
 745 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
 746                        int addr_len, int flags)
 747 {
 748         struct sock *sk = sock->sk;
 749         struct x25_sock *x25 = x25_sk(sk);
 750         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 751         struct x25_route *rt;
 752         int rc = 0;
 753
 754         lock_sock(sk);
 755         if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 756                 sock->state = SS_CONNECTED;
 757                 goto out; /* Connect completed during a ERESTARTSYS event */
 758         }
 759
 760         rc = -ECONNREFUSED;
 761         if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 762                 sock->state = SS_UNCONNECTED;
 763                 goto out;
 764         }
 765
 766         rc = -EISCONN;  /* No reconnect on a seqpacket socket */
 767         if (sk->sk_state == TCP_ESTABLISHED)
 768                 goto out;
 769
 770         rc = -EALREADY; /* Do nothing if call is already in progress */
 771         if (sk->sk_state == TCP_SYN_SENT)
 772                 goto out;
 773
 774         sk->sk_state   = TCP_CLOSE;
 775         sock->state = SS_UNCONNECTED;
 776
 777         rc = -EINVAL;
 778         if (addr_len != sizeof(struct sockaddr_x25) ||
 779             addr->sx25_family != AF_X25 ||
 780             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN)
 781                 goto out;
 782
 783         rc = -ENETUNREACH;
 784         rt = x25_get_route(&addr->sx25_addr);
 785         if (!rt)
 786                 goto out;
 787
 788         x25->neighbour = x25_get_neigh(rt->dev);
 789         if (!x25->neighbour)
 790                 goto out_put_route;
 791
 792         x25_limit_facilities(&x25->facilities, x25->neighbour);
 793
 794         x25->lci = x25_new_lci(x25->neighbour);
 795         if (!x25->lci)
 796                 goto out_put_neigh;
 797
 798         rc = -EINVAL;
 799         if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 800                 goto out_put_neigh;
 801
 802         if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 803                 memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 804
 805         x25->dest_addr = addr->sx25_addr;
 806
 807         /* Move to connecting socket, start sending Connect Requests */
 808         sock->state   = SS_CONNECTING;
 809         sk->sk_state  = TCP_SYN_SENT;
 810
 811         x25->state = X25_STATE_1;
 812
 813         x25_write_internal(sk, X25_CALL_REQUEST);
 814
 815         x25_start_heartbeat(sk);
 816         x25_start_t21timer(sk);
 817
 818         /* Now the loop */
 819         rc = -EINPROGRESS;
 820         if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 821                 goto out;
 822
 823         rc = x25_wait_for_connection_establishment(sk);
 824         if (rc)
 825                 goto out_put_neigh;
 826
 827         sock->state = SS_CONNECTED;
 828         rc = 0;
 829 out_put_neigh:
 830         if (rc && x25->neighbour) {
 831                 read_lock_bh(&x25_list_lock);
 832                 x25_neigh_put(x25->neighbour);
 833                 x25->neighbour = NULL;
 834                 read_unlock_bh(&x25_list_lock);
 835                 x25->state = X25_STATE_0;
 836         }
 837 out_put_route:
 838         x25_route_put(rt);
 839 out:
 840         release_sock(sk);
 841         return rc;
 842 }
 843
 844 static int x25_wait_for_data(struct sock *sk, long timeout)
 845 {
 846         DECLARE_WAITQUEUE(wait, current);
 847         int rc = 0;
 848
 849         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 850         for (;;) {
 851                 __set_current_state(TASK_INTERRUPTIBLE);
 852                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 853                         break;
 854                 rc = -ERESTARTSYS;
 855                 if (signal_pending(current))
 856                         break;
 857                 rc = -EAGAIN;
 858                 if (!timeout)
 859                         break;
 860                 rc = 0;
 861                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 862                         release_sock(sk);
 863                         timeout = schedule_timeout(timeout);
 864                         lock_sock(sk);
 865                 } else
 866                         break;
 867         }
 868         __set_current_state(TASK_RUNNING);
 869         remove_wait_queue(sk_sleep(sk), &wait);
 870         return rc;
 871 }
 872
 873 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 874                       bool kern)
 875 {
 876         struct sock *sk = sock->sk;
 877         struct sock *newsk;
 878         struct sk_buff *skb;
 879         int rc = -EINVAL;
 880
 881         if (!sk)
 882                 goto out;
 883
 884         rc = -EOPNOTSUPP;
 885         if (sk->sk_type != SOCK_SEQPACKET)
 886                 goto out;
 887
 888         lock_sock(sk);
 889         rc = -EINVAL;
 890         if (sk->sk_state != TCP_LISTEN)
 891                 goto out2;
 892
 893         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 894         if (rc)
 895                 goto out2;
 896         skb = skb_dequeue(&sk->sk_receive_queue);
 897         rc = -EINVAL;
 898         if (!skb->sk)
 899                 goto out2;
 900         newsk            = skb->sk;
 901         sock_graft(newsk, newsock);
 902
 903         /* Now attach up the new socket */
 904         skb->sk = NULL;
 905         kfree_skb(skb);
 906         sk_acceptq_removed(sk);
 907         newsock->state = SS_CONNECTED;
 908         rc = 0;
 909 out2:
 910         release_sock(sk);
 911 out:
 912         return rc;
 913 }
 914
 915 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 916                        int peer)
 917 {
 918         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 919         struct sock *sk = sock->sk;
 920         struct x25_sock *x25 = x25_sk(sk);
 921         int rc = 0;
 922
 923         if (peer) {
 924                 if (sk->sk_state != TCP_ESTABLISHED) {
 925                         rc = -ENOTCONN;
 926                         goto out;
 927                 }
 928                 sx25->sx25_addr = x25->dest_addr;
 929         } else
 930                 sx25->sx25_addr = x25->source_addr;
 931
 932         sx25->sx25_family = AF_X25;
 933         rc = sizeof(*sx25);
 934
 935 out:
 936         return rc;
 937 }
 938
 939 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 940                         unsigned int lci)
 941 {
 942         struct sock *sk;
 943         struct sock *make;
 944         struct x25_sock *makex25;
 945         struct x25_address source_addr, dest_addr;
 946         struct x25_facilities facilities;
 947         struct x25_dte_facilities dte_facilities;
 948         int len, addr_len, rc;
 949
 950         /*
 951          *      Remove the LCI and frame type.
 952          */
 953         skb_pull(skb, X25_STD_MIN_LEN);
 954
 955         /*
 956          *      Extract the X.25 addresses and convert them to ASCII strings,
 957          *      and remove them.
 958          *
 959          *      Address block is mandatory in call request packets
 960          */
 961         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 962         if (addr_len <= 0)
 963                 goto out_clear_request;
 964         skb_pull(skb, addr_len);
 965
 966         /*
 967          *      Get the length of the facilities, skip past them for the moment
 968          *      get the call user data because this is needed to determine
 969          *      the correct listener
 970          *
 971          *      Facilities length is mandatory in call request packets
 972          */
 973         if (!pskb_may_pull(skb, 1))
 974                 goto out_clear_request;
 975         len = skb->data[0] + 1;
 976         if (!pskb_may_pull(skb, len))
 977                 goto out_clear_request;
 978         skb_pull(skb,len);
 979
 980         /*
 981          *      Ensure that the amount of call user data is valid.
 982          */
 983         if (skb->len > X25_MAX_CUD_LEN)
 984                 goto out_clear_request;
 985
 986         /*
 987          *      Get all the call user data so it can be used in
 988          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 989          */
 990         if (!pskb_may_pull(skb, skb->len))
 991                 goto out_clear_request;
 992
 993         /*
 994          *      Find a listener for the particular address/cud pair.
 995          */
 996         sk = x25_find_listener(&source_addr,skb);
 997         skb_push(skb,len);
 998
 999         if (sk != NULL && sk_acceptq_is_full(sk)) {
1000                 goto out_sock_put;
1001         }
1002
1003         /*
1004          *      We dont have any listeners for this incoming call.
1005          *      Try forwarding it.
1006          */
1007         if (sk == NULL) {
1008                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
1009                 if (sysctl_x25_forward &&
1010                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1011                 {
1012                         /* Call was forwarded, dont process it any more */
1013                         kfree_skb(skb);
1014                         rc = 1;
1015                         goto out;
1016                 } else {
1017                         /* No listeners, can't forward, clear the call */
1018                         goto out_clear_request;
1019                 }
1020         }
1021
1022         /*
1023          *      Try to reach a compromise on the requested facilities.
1024          */
1025         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1026         if (len == -1)
1027                 goto out_sock_put;
1028
1029         /*
1030          * current neighbour/link might impose additional limits
1031          * on certain facilties
1032          */
1033
1034         x25_limit_facilities(&facilities, nb);
1035
1036         /*
1037          *      Try to create a new socket.
1038          */
1039         make = x25_make_new(sk);
1040         if (!make)
1041                 goto out_sock_put;
1042
1043         /*
1044          *      Remove the facilities
1045          */
1046         skb_pull(skb, len);
1047
1048         skb->sk     = make;
1049         make->sk_state = TCP_ESTABLISHED;
1050
1051         makex25 = x25_sk(make);
1052         makex25->lci           = lci;
1053         makex25->dest_addr     = dest_addr;
1054         makex25->source_addr   = source_addr;
1055         x25_neigh_hold(nb);
1056         makex25->neighbour     = nb;
1057         makex25->facilities    = facilities;
1058         makex25->dte_facilities= dte_facilities;
1059         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1060         /* ensure no reverse facil on accept */
1061         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1062         /* ensure no calling address extension on accept */
1063         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1064         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1065
1066         /* Normally all calls are accepted immediately */
1067         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1068                 x25_write_internal(make, X25_CALL_ACCEPTED);
1069                 makex25->state = X25_STATE_3;
1070         } else {
1071                 makex25->state = X25_STATE_5;
1072         }
1073
1074         /*
1075          *      Incoming Call User Data.
1076          */
1077         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1078         makex25->calluserdata.cudlength = skb->len;
1079
1080         sk_acceptq_added(sk);
1081
1082         x25_insert_socket(make);
1083
1084         skb_queue_head(&sk->sk_receive_queue, skb);
1085
1086         x25_start_heartbeat(make);
1087
1088         if (!sock_flag(sk, SOCK_DEAD))
1089                 sk->sk_data_ready(sk);
1090         rc = 1;
1091         sock_put(sk);
1092 out:
1093         return rc;
1094 out_sock_put:
1095         sock_put(sk);
1096 out_clear_request:
1097         rc = 0;
1098         x25_transmit_clear_request(nb, lci, 0x01);
1099         goto out;
1100 }
1101
1102 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1103 {
1104         struct sock *sk = sock->sk;
1105         struct x25_sock *x25 = x25_sk(sk);
1106         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1107         struct sockaddr_x25 sx25;
1108         struct sk_buff *skb;
1109         unsigned char *asmptr;
1110         int noblock = msg->msg_flags & MSG_DONTWAIT;
1111         size_t size;
1112         int qbit = 0, rc = -EINVAL;
1113
1114         lock_sock(sk);
1115         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1116                 goto out;
1117
1118         /* we currently don't support segmented records at the user interface */
1119         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1120                 goto out;
1121
1122         rc = -EADDRNOTAVAIL;
1123         if (sock_flag(sk, SOCK_ZAPPED))
1124                 goto out;
1125
1126         rc = -EPIPE;
1127         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1128                 send_sig(SIGPIPE, current, 0);
1129                 goto out;
1130         }
1131
1132         rc = -ENETUNREACH;
1133         if (!x25->neighbour)
1134                 goto out;
1135
1136         if (usx25) {
1137                 rc = -EINVAL;
1138                 if (msg->msg_namelen < sizeof(sx25))
1139                         goto out;
1140                 memcpy(&sx25, usx25, sizeof(sx25));
1141                 rc = -EISCONN;
1142                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1143                         goto out;
1144                 rc = -EINVAL;
1145                 if (sx25.sx25_family != AF_X25)
1146                         goto out;
1147         } else {
1148                 /*
1149                  *      FIXME 1003.1g - if the socket is like this because
1150                  *      it has become closed (not started closed) we ought
1151                  *      to SIGPIPE, EPIPE;
1152                  */
1153                 rc = -ENOTCONN;
1154                 if (sk->sk_state != TCP_ESTABLISHED)
1155                         goto out;
1156
1157                 sx25.sx25_family = AF_X25;
1158                 sx25.sx25_addr   = x25->dest_addr;
1159         }
1160
1161         /* Sanity check the packet size */
1162         if (len > 65535) {
1163                 rc = -EMSGSIZE;
1164                 goto out;
1165         }
1166
1167         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1168
1169         /* Build a packet */
1170         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1171
1172         if ((msg->msg_flags & MSG_OOB) && len > 32)
1173                 len = 32;
1174
1175         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1176
1177         release_sock(sk);
1178         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1179         lock_sock(sk);
1180         if (!skb)
1181                 goto out;
1182         X25_SKB_CB(skb)->flags = msg->msg_flags;
1183
1184         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1185
1186         /*
1187          *      Put the data on the end
1188          */
1189         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1190
1191         skb_reset_transport_header(skb);
1192         skb_put(skb, len);
1193
1194         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1195         if (rc)
1196                 goto out_kfree_skb;
1197
1198         /*
1199          *      If the Q BIT Include socket option is in force, the first
1200          *      byte of the user data is the logical value of the Q Bit.
1201          */
1202         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1203                 if (!pskb_may_pull(skb, 1))
1204                         goto out_kfree_skb;
1205
1206                 qbit = skb->data[0];
1207                 skb_pull(skb, 1);
1208         }
1209
1210         /*
1211          *      Push down the X.25 header
1212          */
1213         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1214
1215         if (msg->msg_flags & MSG_OOB) {
1216                 if (x25->neighbour->extended) {
1217                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1218                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1219                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1220                         *asmptr++ = X25_INTERRUPT;
1221                 } else {
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_INTERRUPT;
1226                 }
1227         } else {
1228                 if (x25->neighbour->extended) {
1229                         /* Build an Extended X.25 header */
1230                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1231                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1232                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1233                         *asmptr++ = X25_DATA;
1234                         *asmptr++ = X25_DATA;
1235                 } else {
1236                         /* Build an Standard X.25 header */
1237                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1238                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1239                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1240                         *asmptr++ = X25_DATA;
1241                 }
1242
1243                 if (qbit)
1244                         skb->data[0] |= X25_Q_BIT;
1245         }
1246
1247         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1248         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1249
1250         rc = -ENOTCONN;
1251         if (sk->sk_state != TCP_ESTABLISHED)
1252                 goto out_kfree_skb;
1253
1254         if (msg->msg_flags & MSG_OOB)
1255                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1256         else {
1257                 rc = x25_output(sk, skb);
1258                 len = rc;
1259                 if (rc < 0)
1260                         kfree_skb(skb);
1261                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1262                         len++;
1263         }
1264
1265         x25_kick(sk);
1266         rc = len;
1267 out:
1268         release_sock(sk);
1269         return rc;
1270 out_kfree_skb:
1271         kfree_skb(skb);
1272         goto out;
1273 }
1274
1275
1276 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1277                        int flags)
1278 {
1279         struct sock *sk = sock->sk;
1280         struct x25_sock *x25 = x25_sk(sk);
1281         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1282         size_t copied;
1283         int qbit, header_len;
1284         struct sk_buff *skb;
1285         unsigned char *asmptr;
1286         int rc = -ENOTCONN;
1287
1288         lock_sock(sk);
1289
1290         if (x25->neighbour == NULL)
1291                 goto out;
1292
1293         header_len = x25->neighbour->extended ?
1294                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1295
1296         /*
1297          * This works for seqpacket too. The receiver has ordered the queue for
1298          * us! We do one quick check first though
1299          */
1300         if (sk->sk_state != TCP_ESTABLISHED)
1301                 goto out;
1302
1303         if (flags & MSG_OOB) {
1304                 rc = -EINVAL;
1305                 if (sock_flag(sk, SOCK_URGINLINE) ||
1306                     !skb_peek(&x25->interrupt_in_queue))
1307                         goto out;
1308
1309                 skb = skb_dequeue(&x25->interrupt_in_queue);
1310
1311                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1312                         goto out_free_dgram;
1313
1314                 skb_pull(skb, X25_STD_MIN_LEN);
1315
1316                 /*
1317                  *      No Q bit information on Interrupt data.
1318                  */
1319                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1320                         asmptr  = skb_push(skb, 1);
1321                         *asmptr = 0x00;
1322                 }
1323
1324                 msg->msg_flags |= MSG_OOB;
1325         } else {
1326                 /* Now we can treat all alike */
1327                 release_sock(sk);
1328                 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1329                                         flags & MSG_DONTWAIT, &rc);
1330                 lock_sock(sk);
1331                 if (!skb)
1332                         goto out;
1333
1334                 if (!pskb_may_pull(skb, header_len))
1335                         goto out_free_dgram;
1336
1337                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1338
1339                 skb_pull(skb, header_len);
1340
1341                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1342                         asmptr  = skb_push(skb, 1);
1343                         *asmptr = qbit;
1344                 }
1345         }
1346
1347         skb_reset_transport_header(skb);
1348         copied = skb->len;
1349
1350         if (copied > size) {
1351                 copied = size;
1352                 msg->msg_flags |= MSG_TRUNC;
1353         }
1354
1355         /* Currently, each datagram always contains a complete record */
1356         msg->msg_flags |= MSG_EOR;
1357
1358         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1359         if (rc)
1360                 goto out_free_dgram;
1361
1362         if (sx25) {
1363                 sx25->sx25_family = AF_X25;
1364                 sx25->sx25_addr   = x25->dest_addr;
1365                 msg->msg_namelen = sizeof(*sx25);
1366         }
1367
1368         x25_check_rbuf(sk);
1369         rc = copied;
1370 out_free_dgram:
1371         skb_free_datagram(sk, skb);
1372 out:
1373         release_sock(sk);
1374         return rc;
1375 }
1376
1377
1378 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1379 {
1380         struct sock *sk = sock->sk;
1381         struct x25_sock *x25 = x25_sk(sk);
1382         void __user *argp = (void __user *)arg;
1383         int rc;
1384
1385         switch (cmd) {
1386         case TIOCOUTQ: {
1387                 int amount;
1388
1389                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1390                 if (amount < 0)
1391                         amount = 0;
1392                 rc = put_user(amount, (unsigned int __user *)argp);
1393                 break;
1394         }
1395
1396         case TIOCINQ: {
1397                 struct sk_buff *skb;
1398                 int amount = 0;
1399                 /*
1400                  * These two are safe on a single CPU system as
1401                  * only user tasks fiddle here
1402                  */
1403                 lock_sock(sk);
1404                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1405                         amount = skb->len;
1406                 release_sock(sk);
1407                 rc = put_user(amount, (unsigned int __user *)argp);
1408                 break;
1409         }
1410
1411         case SIOCGIFADDR:
1412         case SIOCSIFADDR:
1413         case SIOCGIFDSTADDR:
1414         case SIOCSIFDSTADDR:
1415         case SIOCGIFBRDADDR:
1416         case SIOCSIFBRDADDR:
1417         case SIOCGIFNETMASK:
1418         case SIOCSIFNETMASK:
1419         case SIOCGIFMETRIC:
1420         case SIOCSIFMETRIC:
1421                 rc = -EINVAL;
1422                 break;
1423         case SIOCADDRT:
1424         case SIOCDELRT:
1425                 rc = -EPERM;
1426                 if (!capable(CAP_NET_ADMIN))
1427                         break;
1428                 rc = x25_route_ioctl(cmd, argp);
1429                 break;
1430         case SIOCX25GSUBSCRIP:
1431                 rc = x25_subscr_ioctl(cmd, argp);
1432                 break;
1433         case SIOCX25SSUBSCRIP:
1434                 rc = -EPERM;
1435                 if (!capable(CAP_NET_ADMIN))
1436                         break;
1437                 rc = x25_subscr_ioctl(cmd, argp);
1438                 break;
1439         case SIOCX25GFACILITIES: {
1440                 lock_sock(sk);
1441                 rc = copy_to_user(argp, &x25->facilities,
1442                                   sizeof(x25->facilities))
1443                         ? -EFAULT : 0;
1444                 release_sock(sk);
1445                 break;
1446         }
1447
1448         case SIOCX25SFACILITIES: {
1449                 struct x25_facilities facilities;
1450                 rc = -EFAULT;
1451                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1452                         break;
1453                 rc = -EINVAL;
1454                 lock_sock(sk);
1455                 if (sk->sk_state != TCP_LISTEN &&
1456                     sk->sk_state != TCP_CLOSE)
1457                         goto out_fac_release;
1458                 if (facilities.pacsize_in < X25_PS16 ||
1459                     facilities.pacsize_in > X25_PS4096)
1460                         goto out_fac_release;
1461                 if (facilities.pacsize_out < X25_PS16 ||
1462                     facilities.pacsize_out > X25_PS4096)
1463                         goto out_fac_release;
1464                 if (facilities.winsize_in < 1 ||
1465                     facilities.winsize_in > 127)
1466                         goto out_fac_release;
1467                 if (facilities.throughput) {
1468                         int out = facilities.throughput & 0xf0;
1469                         int in  = facilities.throughput & 0x0f;
1470                         if (!out)
1471                                 facilities.throughput |=
1472                                         X25_DEFAULT_THROUGHPUT << 4;
1473                         else if (out < 0x30 || out > 0xD0)
1474                                 goto out_fac_release;
1475                         if (!in)
1476                                 facilities.throughput |=
1477                                         X25_DEFAULT_THROUGHPUT;
1478                         else if (in < 0x03 || in > 0x0D)
1479                                 goto out_fac_release;
1480                 }
1481                 if (facilities.reverse &&
1482                     (facilities.reverse & 0x81) != 0x81)
1483                         goto out_fac_release;
1484                 x25->facilities = facilities;
1485                 rc = 0;
1486 out_fac_release:
1487                 release_sock(sk);
1488                 break;
1489         }
1490
1491         case SIOCX25GDTEFACILITIES: {
1492                 lock_sock(sk);
1493                 rc = copy_to_user(argp, &x25->dte_facilities,
1494                                   sizeof(x25->dte_facilities));
1495                 release_sock(sk);
1496                 if (rc)
1497                         rc = -EFAULT;
1498                 break;
1499         }
1500
1501         case SIOCX25SDTEFACILITIES: {
1502                 struct x25_dte_facilities dtefacs;
1503                 rc = -EFAULT;
1504                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1505                         break;
1506                 rc = -EINVAL;
1507                 lock_sock(sk);
1508                 if (sk->sk_state != TCP_LISTEN &&
1509                     sk->sk_state != TCP_CLOSE)
1510                         goto out_dtefac_release;
1511                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1512                         goto out_dtefac_release;
1513                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1514                         goto out_dtefac_release;
1515                 x25->dte_facilities = dtefacs;
1516                 rc = 0;
1517 out_dtefac_release:
1518                 release_sock(sk);
1519                 break;
1520         }
1521
1522         case SIOCX25GCALLUSERDATA: {
1523                 lock_sock(sk);
1524                 rc = copy_to_user(argp, &x25->calluserdata,
1525                                   sizeof(x25->calluserdata))
1526                         ? -EFAULT : 0;
1527                 release_sock(sk);
1528                 break;
1529         }
1530
1531         case SIOCX25SCALLUSERDATA: {
1532                 struct x25_calluserdata calluserdata;
1533
1534                 rc = -EFAULT;
1535                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1536                         break;
1537                 rc = -EINVAL;
1538                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1539                         break;
1540                 lock_sock(sk);
1541                 x25->calluserdata = calluserdata;
1542                 release_sock(sk);
1543                 rc = 0;
1544                 break;
1545         }
1546
1547         case SIOCX25GCAUSEDIAG: {
1548                 lock_sock(sk);
1549                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1550                         ? -EFAULT : 0;
1551                 release_sock(sk);
1552                 break;
1553         }
1554
1555         case SIOCX25SCAUSEDIAG: {
1556                 struct x25_causediag causediag;
1557                 rc = -EFAULT;
1558                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1559                         break;
1560                 lock_sock(sk);
1561                 x25->causediag = causediag;
1562                 release_sock(sk);
1563                 rc = 0;
1564                 break;
1565
1566         }
1567
1568         case SIOCX25SCUDMATCHLEN: {
1569                 struct x25_subaddr sub_addr;
1570                 rc = -EINVAL;
1571                 lock_sock(sk);
1572                 if(sk->sk_state != TCP_CLOSE)
1573                         goto out_cud_release;
1574                 rc = -EFAULT;
1575                 if (copy_from_user(&sub_addr, argp,
1576                                    sizeof(sub_addr)))
1577                         goto out_cud_release;
1578                 rc = -EINVAL;
1579                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1580                         goto out_cud_release;
1581                 x25->cudmatchlength = sub_addr.cudmatchlength;
1582                 rc = 0;
1583 out_cud_release:
1584                 release_sock(sk);
1585                 break;
1586         }
1587
1588         case SIOCX25CALLACCPTAPPRV: {
1589                 rc = -EINVAL;
1590                 lock_sock(sk);
1591                 if (sk->sk_state == TCP_CLOSE) {
1592                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1593                         rc = 0;
1594                 }
1595                 release_sock(sk);
1596                 break;
1597         }
1598
1599         case SIOCX25SENDCALLACCPT:  {
1600                 rc = -EINVAL;
1601                 lock_sock(sk);
1602                 if (sk->sk_state != TCP_ESTABLISHED)
1603                         goto out_sendcallaccpt_release;
1604                 /* must call accptapprv above */
1605                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1606                         goto out_sendcallaccpt_release;
1607                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1608                 x25->state = X25_STATE_3;
1609                 rc = 0;
1610 out_sendcallaccpt_release:
1611                 release_sock(sk);
1612                 break;
1613         }
1614
1615         default:
1616                 rc = -ENOIOCTLCMD;
1617                 break;
1618         }
1619
1620         return rc;
1621 }
1622
1623 static const struct net_proto_family x25_family_ops = {
1624         .family =       AF_X25,
1625         .create =       x25_create,
1626         .owner  =       THIS_MODULE,
1627 };
1628
1629 #ifdef CONFIG_COMPAT
1630 static int compat_x25_subscr_ioctl(unsigned int cmd,
1631                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1632 {
1633         struct compat_x25_subscrip_struct x25_subscr;
1634         struct x25_neigh *nb;
1635         struct net_device *dev;
1636         int rc = -EINVAL;
1637
1638         rc = -EFAULT;
1639         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1640                 goto out;
1641
1642         rc = -EINVAL;
1643         dev = x25_dev_get(x25_subscr.device);
1644         if (dev == NULL)
1645                 goto out;
1646
1647         nb = x25_get_neigh(dev);
1648         if (nb == NULL)
1649                 goto out_dev_put;
1650
1651         dev_put(dev);
1652
1653         if (cmd == SIOCX25GSUBSCRIP) {
1654                 read_lock_bh(&x25_neigh_list_lock);
1655                 x25_subscr.extended = nb->extended;
1656                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1657                 read_unlock_bh(&x25_neigh_list_lock);
1658                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1659                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1660         } else {
1661                 rc = -EINVAL;
1662                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1663                         rc = 0;
1664                         write_lock_bh(&x25_neigh_list_lock);
1665                         nb->extended = x25_subscr.extended;
1666                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1667                         write_unlock_bh(&x25_neigh_list_lock);
1668                 }
1669         }
1670         x25_neigh_put(nb);
1671 out:
1672         return rc;
1673 out_dev_put:
1674         dev_put(dev);
1675         goto out;
1676 }
1677
1678 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1679                                 unsigned long arg)
1680 {
1681         void __user *argp = compat_ptr(arg);
1682         int rc = -ENOIOCTLCMD;
1683
1684         switch(cmd) {
1685         case TIOCOUTQ:
1686         case TIOCINQ:
1687                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1688                 break;
1689         case SIOCGIFADDR:
1690         case SIOCSIFADDR:
1691         case SIOCGIFDSTADDR:
1692         case SIOCSIFDSTADDR:
1693         case SIOCGIFBRDADDR:
1694         case SIOCSIFBRDADDR:
1695         case SIOCGIFNETMASK:
1696         case SIOCSIFNETMASK:
1697         case SIOCGIFMETRIC:
1698         case SIOCSIFMETRIC:
1699                 rc = -EINVAL;
1700                 break;
1701         case SIOCADDRT:
1702         case SIOCDELRT:
1703                 rc = -EPERM;
1704                 if (!capable(CAP_NET_ADMIN))
1705                         break;
1706                 rc = x25_route_ioctl(cmd, argp);
1707                 break;
1708         case SIOCX25GSUBSCRIP:
1709                 rc = compat_x25_subscr_ioctl(cmd, argp);
1710                 break;
1711         case SIOCX25SSUBSCRIP:
1712                 rc = -EPERM;
1713                 if (!capable(CAP_NET_ADMIN))
1714                         break;
1715                 rc = compat_x25_subscr_ioctl(cmd, argp);
1716                 break;
1717         case SIOCX25GFACILITIES:
1718         case SIOCX25SFACILITIES:
1719         case SIOCX25GDTEFACILITIES:
1720         case SIOCX25SDTEFACILITIES:
1721         case SIOCX25GCALLUSERDATA:
1722         case SIOCX25SCALLUSERDATA:
1723         case SIOCX25GCAUSEDIAG:
1724         case SIOCX25SCAUSEDIAG:
1725         case SIOCX25SCUDMATCHLEN:
1726         case SIOCX25CALLACCPTAPPRV:
1727         case SIOCX25SENDCALLACCPT:
1728                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1729                 break;
1730         default:
1731                 rc = -ENOIOCTLCMD;
1732                 break;
1733         }
1734         return rc;
1735 }
1736 #endif
1737
1738 static const struct proto_ops x25_proto_ops = {
1739         .family =       AF_X25,
1740         .owner =        THIS_MODULE,
1741         .release =      x25_release,
1742         .bind =         x25_bind,
1743         .connect =      x25_connect,
1744         .socketpair =   sock_no_socketpair,
1745         .accept =       x25_accept,
1746         .getname =      x25_getname,
1747         .poll =         datagram_poll,
1748         .ioctl =        x25_ioctl,
1749 #ifdef CONFIG_COMPAT
1750         .compat_ioctl = compat_x25_ioctl,
1751 #endif
1752         .gettstamp =    sock_gettstamp,
1753         .listen =       x25_listen,
1754         .shutdown =     sock_no_shutdown,
1755         .setsockopt =   x25_setsockopt,
1756         .getsockopt =   x25_getsockopt,
1757         .sendmsg =      x25_sendmsg,
1758         .recvmsg =      x25_recvmsg,
1759         .mmap =         sock_no_mmap,
1760         .sendpage =     sock_no_sendpage,
1761 };
1762
1763 static struct packet_type x25_packet_type __read_mostly = {
1764         .type = cpu_to_be16(ETH_P_X25),
1765         .func = x25_lapb_receive_frame,
1766 };
1767
1768 static struct notifier_block x25_dev_notifier = {
1769         .notifier_call = x25_device_event,
1770 };
1771
1772 void x25_kill_by_neigh(struct x25_neigh *nb)
1773 {
1774         struct sock *s;
1775
1776         write_lock_bh(&x25_list_lock);
1777
1778         sk_for_each(s, &x25_list)
1779                 if (x25_sk(s)->neighbour == nb)
1780                         x25_disconnect(s, ENETUNREACH, 0, 0);
1781
1782         write_unlock_bh(&x25_list_lock);
1783
1784         /* Remove any related forwards */
1785         x25_clear_forward_by_dev(nb->dev);
1786 }
1787
1788 static int __init x25_init(void)
1789 {
1790         int rc;
1791
1792         rc = proto_register(&x25_proto, 0);
1793         if (rc)
1794                 goto out;
1795
1796         rc = sock_register(&x25_family_ops);
1797         if (rc)
1798                 goto out_proto;
1799
1800         dev_add_pack(&x25_packet_type);
1801
1802         rc = register_netdevice_notifier(&x25_dev_notifier);
1803         if (rc)
1804                 goto out_sock;
1805
1806         rc = x25_register_sysctl();
1807         if (rc)
1808                 goto out_dev;
1809
1810         rc = x25_proc_init();
1811         if (rc)
1812                 goto out_sysctl;
1813
1814         pr_info("Linux Version 0.2\n");
1815
1816 out:
1817         return rc;
1818 out_sysctl:
1819         x25_unregister_sysctl();
1820 out_dev:
1821         unregister_netdevice_notifier(&x25_dev_notifier);
1822 out_sock:
1823         dev_remove_pack(&x25_packet_type);
1824         sock_unregister(AF_X25);
1825 out_proto:
1826         proto_unregister(&x25_proto);
1827         goto out;
1828 }
1829 module_init(x25_init);
1830
1831 static void __exit x25_exit(void)
1832 {
1833         x25_proc_exit();
1834         x25_link_free();
1835         x25_route_free();
1836
1837         x25_unregister_sysctl();
1838
1839         unregister_netdevice_notifier(&x25_dev_notifier);
1840
1841         dev_remove_pack(&x25_packet_type);
1842
1843         sock_unregister(AF_X25);
1844         proto_unregister(&x25_proto);
1845 }
1846 module_exit(x25_exit);
1847
1848 MODULE_AUTHOR("Jonathan Naylor <[email protected]>");
1849 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1850 MODULE_LICENSE("GPL");
1851 MODULE_ALIAS_NETPROTO(PF_X25);