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         rc = -EINVAL;
 474         if (len < 0)
 475                 goto out;
 476
 477         len = min_t(unsigned int, len, sizeof(int));
 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 (sock->state != SS_UNCONNECTED) {
 496                 rc = -EINVAL;
 497                 release_sock(sk);
 498                 return rc;
 499         }
 500
 501         if (sk->sk_state != TCP_LISTEN) {
 502                 memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 503                 sk->sk_max_ack_backlog = backlog;
 504                 sk->sk_state           = TCP_LISTEN;
 505                 rc = 0;
 506         }
 507         release_sock(sk);
 508
 509         return rc;
 510 }
 511
 512 static struct proto x25_proto = {
 513         .name     = "X25",
 514         .owner    = THIS_MODULE,
 515         .obj_size = sizeof(struct x25_sock),
 516 };
 517
 518 static struct sock *x25_alloc_socket(struct net *net, int kern)
 519 {
 520         struct x25_sock *x25;
 521         struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 522
 523         if (!sk)
 524                 goto out;
 525
 526         sock_init_data(NULL, sk);
 527
 528         x25 = x25_sk(sk);
 529         skb_queue_head_init(&x25->ack_queue);
 530         skb_queue_head_init(&x25->fragment_queue);
 531         skb_queue_head_init(&x25->interrupt_in_queue);
 532         skb_queue_head_init(&x25->interrupt_out_queue);
 533 out:
 534         return sk;
 535 }
 536
 537 static int x25_create(struct net *net, struct socket *sock, int protocol,
 538                       int kern)
 539 {
 540         struct sock *sk;
 541         struct x25_sock *x25;
 542         int rc = -EAFNOSUPPORT;
 543
 544         if (!net_eq(net, &init_net))
 545                 goto out;
 546
 547         rc = -ESOCKTNOSUPPORT;
 548         if (sock->type != SOCK_SEQPACKET)
 549                 goto out;
 550
 551         rc = -EINVAL;
 552         if (protocol)
 553                 goto out;
 554
 555         rc = -ENOMEM;
 556         if ((sk = x25_alloc_socket(net, kern)) == NULL)
 557                 goto out;
 558
 559         x25 = x25_sk(sk);
 560
 561         sock_init_data(sock, sk);
 562
 563         x25_init_timers(sk);
 564
 565         sock->ops    = &x25_proto_ops;
 566         sk->sk_protocol = protocol;
 567         sk->sk_backlog_rcv = x25_backlog_rcv;
 568
 569         x25->t21   = sysctl_x25_call_request_timeout;
 570         x25->t22   = sysctl_x25_reset_request_timeout;
 571         x25->t23   = sysctl_x25_clear_request_timeout;
 572         x25->t2    = sysctl_x25_ack_holdback_timeout;
 573         x25->state = X25_STATE_0;
 574         x25->cudmatchlength = 0;
 575         set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);     /* normally no cud  */
 576                                                         /* on call accept   */
 577
 578         x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 579         x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 580         x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 581         x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 582         x25->facilities.throughput  = 0;        /* by default don't negotiate
 583                                                    throughput */
 584         x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 585         x25->dte_facilities.calling_len = 0;
 586         x25->dte_facilities.called_len = 0;
 587         memset(x25->dte_facilities.called_ae, '\0',
 588                         sizeof(x25->dte_facilities.called_ae));
 589         memset(x25->dte_facilities.calling_ae, '\0',
 590                         sizeof(x25->dte_facilities.calling_ae));
 591
 592         rc = 0;
 593 out:
 594         return rc;
 595 }
 596
 597 static struct sock *x25_make_new(struct sock *osk)
 598 {
 599         struct sock *sk = NULL;
 600         struct x25_sock *x25, *ox25;
 601
 602         if (osk->sk_type != SOCK_SEQPACKET)
 603                 goto out;
 604
 605         if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 606                 goto out;
 607
 608         x25 = x25_sk(sk);
 609
 610         sk->sk_type        = osk->sk_type;
 611         sk->sk_priority    = osk->sk_priority;
 612         sk->sk_protocol    = osk->sk_protocol;
 613         sk->sk_rcvbuf      = osk->sk_rcvbuf;
 614         sk->sk_sndbuf      = osk->sk_sndbuf;
 615         sk->sk_state       = TCP_ESTABLISHED;
 616         sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 617         sock_copy_flags(sk, osk);
 618
 619         ox25 = x25_sk(osk);
 620         x25->t21        = ox25->t21;
 621         x25->t22        = ox25->t22;
 622         x25->t23        = ox25->t23;
 623         x25->t2         = ox25->t2;
 624         x25->flags      = ox25->flags;
 625         x25->facilities = ox25->facilities;
 626         x25->dte_facilities = ox25->dte_facilities;
 627         x25->cudmatchlength = ox25->cudmatchlength;
 628
 629         clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 630         x25_init_timers(sk);
 631 out:
 632         return sk;
 633 }
 634
 635 static int x25_release(struct socket *sock)
 636 {
 637         struct sock *sk = sock->sk;
 638         struct x25_sock *x25;
 639
 640         if (!sk)
 641                 return 0;
 642
 643         x25 = x25_sk(sk);
 644
 645         sock_hold(sk);
 646         lock_sock(sk);
 647         switch (x25->state) {
 648
 649                 case X25_STATE_0:
 650                 case X25_STATE_2:
 651                         x25_disconnect(sk, 0, 0, 0);
 652                         __x25_destroy_socket(sk);
 653                         goto out;
 654
 655                 case X25_STATE_1:
 656                 case X25_STATE_3:
 657                 case X25_STATE_4:
 658                         x25_clear_queues(sk);
 659                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 660                         x25_start_t23timer(sk);
 661                         x25->state = X25_STATE_2;
 662                         sk->sk_state    = TCP_CLOSE;
 663                         sk->sk_shutdown |= SEND_SHUTDOWN;
 664                         sk->sk_state_change(sk);
 665                         sock_set_flag(sk, SOCK_DEAD);
 666                         sock_set_flag(sk, SOCK_DESTROY);
 667                         break;
 668
 669                 case X25_STATE_5:
 670                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 671                         x25_disconnect(sk, 0, 0, 0);
 672                         __x25_destroy_socket(sk);
 673                         goto out;
 674         }
 675
 676         sock_orphan(sk);
 677 out:
 678         release_sock(sk);
 679         sock_put(sk);
 680         return 0;
 681 }
 682
 683 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 684 {
 685         struct sock *sk = sock->sk;
 686         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 687         int len, i, rc = 0;
 688
 689         if (addr_len != sizeof(struct sockaddr_x25) ||
 690             addr->sx25_family != AF_X25 ||
 691             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) {
 692                 rc = -EINVAL;
 693                 goto out;
 694         }
 695
 696         /* check for the null_x25_address */
 697         if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
 698
 699                 len = strlen(addr->sx25_addr.x25_addr);
 700                 for (i = 0; i < len; i++) {
 701                         if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 702                                 rc = -EINVAL;
 703                                 goto out;
 704                         }
 705                 }
 706         }
 707
 708         lock_sock(sk);
 709         if (sock_flag(sk, SOCK_ZAPPED)) {
 710                 x25_sk(sk)->source_addr = addr->sx25_addr;
 711                 x25_insert_socket(sk);
 712                 sock_reset_flag(sk, SOCK_ZAPPED);
 713         } else {
 714                 rc = -EINVAL;
 715         }
 716         release_sock(sk);
 717         SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
 718 out:
 719         return rc;
 720 }
 721
 722 static int x25_wait_for_connection_establishment(struct sock *sk)
 723 {
 724         DECLARE_WAITQUEUE(wait, current);
 725         int rc;
 726
 727         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 728         for (;;) {
 729                 __set_current_state(TASK_INTERRUPTIBLE);
 730                 rc = -ERESTARTSYS;
 731                 if (signal_pending(current))
 732                         break;
 733                 rc = sock_error(sk);
 734                 if (rc) {
 735                         sk->sk_socket->state = SS_UNCONNECTED;
 736                         break;
 737                 }
 738                 rc = 0;
 739                 if (sk->sk_state != TCP_ESTABLISHED) {
 740                         release_sock(sk);
 741                         schedule();
 742                         lock_sock(sk);
 743                 } else
 744                         break;
 745         }
 746         __set_current_state(TASK_RUNNING);
 747         remove_wait_queue(sk_sleep(sk), &wait);
 748         return rc;
 749 }
 750
 751 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
 752                        int addr_len, int flags)
 753 {
 754         struct sock *sk = sock->sk;
 755         struct x25_sock *x25 = x25_sk(sk);
 756         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 757         struct x25_route *rt;
 758         int rc = 0;
 759
 760         lock_sock(sk);
 761         if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 762                 sock->state = SS_CONNECTED;
 763                 goto out; /* Connect completed during a ERESTARTSYS event */
 764         }
 765
 766         rc = -ECONNREFUSED;
 767         if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 768                 sock->state = SS_UNCONNECTED;
 769                 goto out;
 770         }
 771
 772         rc = -EISCONN;  /* No reconnect on a seqpacket socket */
 773         if (sk->sk_state == TCP_ESTABLISHED)
 774                 goto out;
 775
 776         rc = -EALREADY; /* Do nothing if call is already in progress */
 777         if (sk->sk_state == TCP_SYN_SENT)
 778                 goto out;
 779
 780         sk->sk_state   = TCP_CLOSE;
 781         sock->state = SS_UNCONNECTED;
 782
 783         rc = -EINVAL;
 784         if (addr_len != sizeof(struct sockaddr_x25) ||
 785             addr->sx25_family != AF_X25 ||
 786             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN)
 787                 goto out;
 788
 789         rc = -ENETUNREACH;
 790         rt = x25_get_route(&addr->sx25_addr);
 791         if (!rt)
 792                 goto out;
 793
 794         x25->neighbour = x25_get_neigh(rt->dev);
 795         if (!x25->neighbour)
 796                 goto out_put_route;
 797
 798         x25_limit_facilities(&x25->facilities, x25->neighbour);
 799
 800         x25->lci = x25_new_lci(x25->neighbour);
 801         if (!x25->lci)
 802                 goto out_put_neigh;
 803
 804         rc = -EINVAL;
 805         if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 806                 goto out_put_neigh;
 807
 808         if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 809                 memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 810
 811         x25->dest_addr = addr->sx25_addr;
 812
 813         /* Move to connecting socket, start sending Connect Requests */
 814         sock->state   = SS_CONNECTING;
 815         sk->sk_state  = TCP_SYN_SENT;
 816
 817         x25->state = X25_STATE_1;
 818
 819         x25_write_internal(sk, X25_CALL_REQUEST);
 820
 821         x25_start_heartbeat(sk);
 822         x25_start_t21timer(sk);
 823
 824         /* Now the loop */
 825         rc = -EINPROGRESS;
 826         if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 827                 goto out;
 828
 829         rc = x25_wait_for_connection_establishment(sk);
 830         if (rc)
 831                 goto out_put_neigh;
 832
 833         sock->state = SS_CONNECTED;
 834         rc = 0;
 835 out_put_neigh:
 836         if (rc && x25->neighbour) {
 837                 read_lock_bh(&x25_list_lock);
 838                 x25_neigh_put(x25->neighbour);
 839                 x25->neighbour = NULL;
 840                 read_unlock_bh(&x25_list_lock);
 841                 x25->state = X25_STATE_0;
 842         }
 843 out_put_route:
 844         x25_route_put(rt);
 845 out:
 846         release_sock(sk);
 847         return rc;
 848 }
 849
 850 static int x25_wait_for_data(struct sock *sk, long timeout)
 851 {
 852         DECLARE_WAITQUEUE(wait, current);
 853         int rc = 0;
 854
 855         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 856         for (;;) {
 857                 __set_current_state(TASK_INTERRUPTIBLE);
 858                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 859                         break;
 860                 rc = -ERESTARTSYS;
 861                 if (signal_pending(current))
 862                         break;
 863                 rc = -EAGAIN;
 864                 if (!timeout)
 865                         break;
 866                 rc = 0;
 867                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 868                         release_sock(sk);
 869                         timeout = schedule_timeout(timeout);
 870                         lock_sock(sk);
 871                 } else
 872                         break;
 873         }
 874         __set_current_state(TASK_RUNNING);
 875         remove_wait_queue(sk_sleep(sk), &wait);
 876         return rc;
 877 }
 878
 879 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 880                       bool kern)
 881 {
 882         struct sock *sk = sock->sk;
 883         struct sock *newsk;
 884         struct sk_buff *skb;
 885         int rc = -EINVAL;
 886
 887         if (!sk)
 888                 goto out;
 889
 890         rc = -EOPNOTSUPP;
 891         if (sk->sk_type != SOCK_SEQPACKET)
 892                 goto out;
 893
 894         lock_sock(sk);
 895         rc = -EINVAL;
 896         if (sk->sk_state != TCP_LISTEN)
 897                 goto out2;
 898
 899         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 900         if (rc)
 901                 goto out2;
 902         skb = skb_dequeue(&sk->sk_receive_queue);
 903         rc = -EINVAL;
 904         if (!skb->sk)
 905                 goto out2;
 906         newsk            = skb->sk;
 907         sock_graft(newsk, newsock);
 908
 909         /* Now attach up the new socket */
 910         skb->sk = NULL;
 911         kfree_skb(skb);
 912         sk_acceptq_removed(sk);
 913         newsock->state = SS_CONNECTED;
 914         rc = 0;
 915 out2:
 916         release_sock(sk);
 917 out:
 918         return rc;
 919 }
 920
 921 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 922                        int peer)
 923 {
 924         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 925         struct sock *sk = sock->sk;
 926         struct x25_sock *x25 = x25_sk(sk);
 927         int rc = 0;
 928
 929         if (peer) {
 930                 if (sk->sk_state != TCP_ESTABLISHED) {
 931                         rc = -ENOTCONN;
 932                         goto out;
 933                 }
 934                 sx25->sx25_addr = x25->dest_addr;
 935         } else
 936                 sx25->sx25_addr = x25->source_addr;
 937
 938         sx25->sx25_family = AF_X25;
 939         rc = sizeof(*sx25);
 940
 941 out:
 942         return rc;
 943 }
 944
 945 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 946                         unsigned int lci)
 947 {
 948         struct sock *sk;
 949         struct sock *make;
 950         struct x25_sock *makex25;
 951         struct x25_address source_addr, dest_addr;
 952         struct x25_facilities facilities;
 953         struct x25_dte_facilities dte_facilities;
 954         int len, addr_len, rc;
 955
 956         /*
 957          *      Remove the LCI and frame type.
 958          */
 959         skb_pull(skb, X25_STD_MIN_LEN);
 960
 961         /*
 962          *      Extract the X.25 addresses and convert them to ASCII strings,
 963          *      and remove them.
 964          *
 965          *      Address block is mandatory in call request packets
 966          */
 967         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 968         if (addr_len <= 0)
 969                 goto out_clear_request;
 970         skb_pull(skb, addr_len);
 971
 972         /*
 973          *      Get the length of the facilities, skip past them for the moment
 974          *      get the call user data because this is needed to determine
 975          *      the correct listener
 976          *
 977          *      Facilities length is mandatory in call request packets
 978          */
 979         if (!pskb_may_pull(skb, 1))
 980                 goto out_clear_request;
 981         len = skb->data[0] + 1;
 982         if (!pskb_may_pull(skb, len))
 983                 goto out_clear_request;
 984         skb_pull(skb,len);
 985
 986         /*
 987          *      Ensure that the amount of call user data is valid.
 988          */
 989         if (skb->len > X25_MAX_CUD_LEN)
 990                 goto out_clear_request;
 991
 992         /*
 993          *      Get all the call user data so it can be used in
 994          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 995          */
 996         if (!pskb_may_pull(skb, skb->len))
 997                 goto out_clear_request;
 998
 999         /*
1000          *      Find a listener for the particular address/cud pair.
1001          */
1002         sk = x25_find_listener(&source_addr,skb);
1003         skb_push(skb,len);
1004
1005         if (sk != NULL && sk_acceptq_is_full(sk)) {
1006                 goto out_sock_put;
1007         }
1008
1009         /*
1010          *      We dont have any listeners for this incoming call.
1011          *      Try forwarding it.
1012          */
1013         if (sk == NULL) {
1014                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
1015                 if (sysctl_x25_forward &&
1016                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1017                 {
1018                         /* Call was forwarded, dont process it any more */
1019                         kfree_skb(skb);
1020                         rc = 1;
1021                         goto out;
1022                 } else {
1023                         /* No listeners, can't forward, clear the call */
1024                         goto out_clear_request;
1025                 }
1026         }
1027
1028         /*
1029          *      Try to reach a compromise on the requested facilities.
1030          */
1031         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1032         if (len == -1)
1033                 goto out_sock_put;
1034
1035         /*
1036          * current neighbour/link might impose additional limits
1037          * on certain facilties
1038          */
1039
1040         x25_limit_facilities(&facilities, nb);
1041
1042         /*
1043          *      Try to create a new socket.
1044          */
1045         make = x25_make_new(sk);
1046         if (!make)
1047                 goto out_sock_put;
1048
1049         /*
1050          *      Remove the facilities
1051          */
1052         skb_pull(skb, len);
1053
1054         skb->sk     = make;
1055         make->sk_state = TCP_ESTABLISHED;
1056
1057         makex25 = x25_sk(make);
1058         makex25->lci           = lci;
1059         makex25->dest_addr     = dest_addr;
1060         makex25->source_addr   = source_addr;
1061         x25_neigh_hold(nb);
1062         makex25->neighbour     = nb;
1063         makex25->facilities    = facilities;
1064         makex25->dte_facilities= dte_facilities;
1065         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1066         /* ensure no reverse facil on accept */
1067         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1068         /* ensure no calling address extension on accept */
1069         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1070         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1071
1072         /* Normally all calls are accepted immediately */
1073         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1074                 x25_write_internal(make, X25_CALL_ACCEPTED);
1075                 makex25->state = X25_STATE_3;
1076         } else {
1077                 makex25->state = X25_STATE_5;
1078         }
1079
1080         /*
1081          *      Incoming Call User Data.
1082          */
1083         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1084         makex25->calluserdata.cudlength = skb->len;
1085
1086         sk_acceptq_added(sk);
1087
1088         x25_insert_socket(make);
1089
1090         skb_queue_head(&sk->sk_receive_queue, skb);
1091
1092         x25_start_heartbeat(make);
1093
1094         if (!sock_flag(sk, SOCK_DEAD))
1095                 sk->sk_data_ready(sk);
1096         rc = 1;
1097         sock_put(sk);
1098 out:
1099         return rc;
1100 out_sock_put:
1101         sock_put(sk);
1102 out_clear_request:
1103         rc = 0;
1104         x25_transmit_clear_request(nb, lci, 0x01);
1105         goto out;
1106 }
1107
1108 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1109 {
1110         struct sock *sk = sock->sk;
1111         struct x25_sock *x25 = x25_sk(sk);
1112         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1113         struct sockaddr_x25 sx25;
1114         struct sk_buff *skb;
1115         unsigned char *asmptr;
1116         int noblock = msg->msg_flags & MSG_DONTWAIT;
1117         size_t size;
1118         int qbit = 0, rc = -EINVAL;
1119
1120         lock_sock(sk);
1121         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1122                 goto out;
1123
1124         /* we currently don't support segmented records at the user interface */
1125         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1126                 goto out;
1127
1128         rc = -EADDRNOTAVAIL;
1129         if (sock_flag(sk, SOCK_ZAPPED))
1130                 goto out;
1131
1132         rc = -EPIPE;
1133         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1134                 send_sig(SIGPIPE, current, 0);
1135                 goto out;
1136         }
1137
1138         rc = -ENETUNREACH;
1139         if (!x25->neighbour)
1140                 goto out;
1141
1142         if (usx25) {
1143                 rc = -EINVAL;
1144                 if (msg->msg_namelen < sizeof(sx25))
1145                         goto out;
1146                 memcpy(&sx25, usx25, sizeof(sx25));
1147                 rc = -EISCONN;
1148                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1149                         goto out;
1150                 rc = -EINVAL;
1151                 if (sx25.sx25_family != AF_X25)
1152                         goto out;
1153         } else {
1154                 /*
1155                  *      FIXME 1003.1g - if the socket is like this because
1156                  *      it has become closed (not started closed) we ought
1157                  *      to SIGPIPE, EPIPE;
1158                  */
1159                 rc = -ENOTCONN;
1160                 if (sk->sk_state != TCP_ESTABLISHED)
1161                         goto out;
1162
1163                 sx25.sx25_family = AF_X25;
1164                 sx25.sx25_addr   = x25->dest_addr;
1165         }
1166
1167         /* Sanity check the packet size */
1168         if (len > 65535) {
1169                 rc = -EMSGSIZE;
1170                 goto out;
1171         }
1172
1173         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1174
1175         /* Build a packet */
1176         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1177
1178         if ((msg->msg_flags & MSG_OOB) && len > 32)
1179                 len = 32;
1180
1181         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1182
1183         release_sock(sk);
1184         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1185         lock_sock(sk);
1186         if (!skb)
1187                 goto out;
1188         X25_SKB_CB(skb)->flags = msg->msg_flags;
1189
1190         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1191
1192         /*
1193          *      Put the data on the end
1194          */
1195         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1196
1197         skb_reset_transport_header(skb);
1198         skb_put(skb, len);
1199
1200         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1201         if (rc)
1202                 goto out_kfree_skb;
1203
1204         /*
1205          *      If the Q BIT Include socket option is in force, the first
1206          *      byte of the user data is the logical value of the Q Bit.
1207          */
1208         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1209                 if (!pskb_may_pull(skb, 1))
1210                         goto out_kfree_skb;
1211
1212                 qbit = skb->data[0];
1213                 skb_pull(skb, 1);
1214         }
1215
1216         /*
1217          *      Push down the X.25 header
1218          */
1219         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1220
1221         if (msg->msg_flags & MSG_OOB) {
1222                 if (x25->neighbour->extended) {
1223                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1224                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1225                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1226                         *asmptr++ = X25_INTERRUPT;
1227                 } else {
1228                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1229                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1230                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1231                         *asmptr++ = X25_INTERRUPT;
1232                 }
1233         } else {
1234                 if (x25->neighbour->extended) {
1235                         /* Build an Extended X.25 header */
1236                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1237                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1238                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1239                         *asmptr++ = X25_DATA;
1240                         *asmptr++ = X25_DATA;
1241                 } else {
1242                         /* Build an Standard X.25 header */
1243                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1244                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1245                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1246                         *asmptr++ = X25_DATA;
1247                 }
1248
1249                 if (qbit)
1250                         skb->data[0] |= X25_Q_BIT;
1251         }
1252
1253         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1254         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1255
1256         rc = -ENOTCONN;
1257         if (sk->sk_state != TCP_ESTABLISHED)
1258                 goto out_kfree_skb;
1259
1260         if (msg->msg_flags & MSG_OOB)
1261                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1262         else {
1263                 rc = x25_output(sk, skb);
1264                 len = rc;
1265                 if (rc < 0)
1266                         kfree_skb(skb);
1267                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1268                         len++;
1269         }
1270
1271         x25_kick(sk);
1272         rc = len;
1273 out:
1274         release_sock(sk);
1275         return rc;
1276 out_kfree_skb:
1277         kfree_skb(skb);
1278         goto out;
1279 }
1280
1281
1282 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1283                        int flags)
1284 {
1285         struct sock *sk = sock->sk;
1286         struct x25_sock *x25 = x25_sk(sk);
1287         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1288         size_t copied;
1289         int qbit, header_len;
1290         struct sk_buff *skb;
1291         unsigned char *asmptr;
1292         int rc = -ENOTCONN;
1293
1294         lock_sock(sk);
1295
1296         if (x25->neighbour == NULL)
1297                 goto out;
1298
1299         header_len = x25->neighbour->extended ?
1300                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1301
1302         /*
1303          * This works for seqpacket too. The receiver has ordered the queue for
1304          * us! We do one quick check first though
1305          */
1306         if (sk->sk_state != TCP_ESTABLISHED)
1307                 goto out;
1308
1309         if (flags & MSG_OOB) {
1310                 rc = -EINVAL;
1311                 if (sock_flag(sk, SOCK_URGINLINE) ||
1312                     !skb_peek(&x25->interrupt_in_queue))
1313                         goto out;
1314
1315                 skb = skb_dequeue(&x25->interrupt_in_queue);
1316
1317                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1318                         goto out_free_dgram;
1319
1320                 skb_pull(skb, X25_STD_MIN_LEN);
1321
1322                 /*
1323                  *      No Q bit information on Interrupt data.
1324                  */
1325                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1326                         asmptr  = skb_push(skb, 1);
1327                         *asmptr = 0x00;
1328                 }
1329
1330                 msg->msg_flags |= MSG_OOB;
1331         } else {
1332                 /* Now we can treat all alike */
1333                 release_sock(sk);
1334                 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1335                                         flags & MSG_DONTWAIT, &rc);
1336                 lock_sock(sk);
1337                 if (!skb)
1338                         goto out;
1339
1340                 if (!pskb_may_pull(skb, header_len))
1341                         goto out_free_dgram;
1342
1343                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1344
1345                 skb_pull(skb, header_len);
1346
1347                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1348                         asmptr  = skb_push(skb, 1);
1349                         *asmptr = qbit;
1350                 }
1351         }
1352
1353         skb_reset_transport_header(skb);
1354         copied = skb->len;
1355
1356         if (copied > size) {
1357                 copied = size;
1358                 msg->msg_flags |= MSG_TRUNC;
1359         }
1360
1361         /* Currently, each datagram always contains a complete record */
1362         msg->msg_flags |= MSG_EOR;
1363
1364         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1365         if (rc)
1366                 goto out_free_dgram;
1367
1368         if (sx25) {
1369                 sx25->sx25_family = AF_X25;
1370                 sx25->sx25_addr   = x25->dest_addr;
1371                 msg->msg_namelen = sizeof(*sx25);
1372         }
1373
1374         x25_check_rbuf(sk);
1375         rc = copied;
1376 out_free_dgram:
1377         skb_free_datagram(sk, skb);
1378 out:
1379         release_sock(sk);
1380         return rc;
1381 }
1382
1383
1384 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1385 {
1386         struct sock *sk = sock->sk;
1387         struct x25_sock *x25 = x25_sk(sk);
1388         void __user *argp = (void __user *)arg;
1389         int rc;
1390
1391         switch (cmd) {
1392         case TIOCOUTQ: {
1393                 int amount;
1394
1395                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1396                 if (amount < 0)
1397                         amount = 0;
1398                 rc = put_user(amount, (unsigned int __user *)argp);
1399                 break;
1400         }
1401
1402         case TIOCINQ: {
1403                 struct sk_buff *skb;
1404                 int amount = 0;
1405                 /*
1406                  * These two are safe on a single CPU system as
1407                  * only user tasks fiddle here
1408                  */
1409                 lock_sock(sk);
1410                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1411                         amount = skb->len;
1412                 release_sock(sk);
1413                 rc = put_user(amount, (unsigned int __user *)argp);
1414                 break;
1415         }
1416
1417         case SIOCGIFADDR:
1418         case SIOCSIFADDR:
1419         case SIOCGIFDSTADDR:
1420         case SIOCSIFDSTADDR:
1421         case SIOCGIFBRDADDR:
1422         case SIOCSIFBRDADDR:
1423         case SIOCGIFNETMASK:
1424         case SIOCSIFNETMASK:
1425         case SIOCGIFMETRIC:
1426         case SIOCSIFMETRIC:
1427                 rc = -EINVAL;
1428                 break;
1429         case SIOCADDRT:
1430         case SIOCDELRT:
1431                 rc = -EPERM;
1432                 if (!capable(CAP_NET_ADMIN))
1433                         break;
1434                 rc = x25_route_ioctl(cmd, argp);
1435                 break;
1436         case SIOCX25GSUBSCRIP:
1437                 rc = x25_subscr_ioctl(cmd, argp);
1438                 break;
1439         case SIOCX25SSUBSCRIP:
1440                 rc = -EPERM;
1441                 if (!capable(CAP_NET_ADMIN))
1442                         break;
1443                 rc = x25_subscr_ioctl(cmd, argp);
1444                 break;
1445         case SIOCX25GFACILITIES: {
1446                 lock_sock(sk);
1447                 rc = copy_to_user(argp, &x25->facilities,
1448                                   sizeof(x25->facilities))
1449                         ? -EFAULT : 0;
1450                 release_sock(sk);
1451                 break;
1452         }
1453
1454         case SIOCX25SFACILITIES: {
1455                 struct x25_facilities facilities;
1456                 rc = -EFAULT;
1457                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1458                         break;
1459                 rc = -EINVAL;
1460                 lock_sock(sk);
1461                 if (sk->sk_state != TCP_LISTEN &&
1462                     sk->sk_state != TCP_CLOSE)
1463                         goto out_fac_release;
1464                 if (facilities.pacsize_in < X25_PS16 ||
1465                     facilities.pacsize_in > X25_PS4096)
1466                         goto out_fac_release;
1467                 if (facilities.pacsize_out < X25_PS16 ||
1468                     facilities.pacsize_out > X25_PS4096)
1469                         goto out_fac_release;
1470                 if (facilities.winsize_in < 1 ||
1471                     facilities.winsize_in > 127)
1472                         goto out_fac_release;
1473                 if (facilities.throughput) {
1474                         int out = facilities.throughput & 0xf0;
1475                         int in  = facilities.throughput & 0x0f;
1476                         if (!out)
1477                                 facilities.throughput |=
1478                                         X25_DEFAULT_THROUGHPUT << 4;
1479                         else if (out < 0x30 || out > 0xD0)
1480                                 goto out_fac_release;
1481                         if (!in)
1482                                 facilities.throughput |=
1483                                         X25_DEFAULT_THROUGHPUT;
1484                         else if (in < 0x03 || in > 0x0D)
1485                                 goto out_fac_release;
1486                 }
1487                 if (facilities.reverse &&
1488                     (facilities.reverse & 0x81) != 0x81)
1489                         goto out_fac_release;
1490                 x25->facilities = facilities;
1491                 rc = 0;
1492 out_fac_release:
1493                 release_sock(sk);
1494                 break;
1495         }
1496
1497         case SIOCX25GDTEFACILITIES: {
1498                 lock_sock(sk);
1499                 rc = copy_to_user(argp, &x25->dte_facilities,
1500                                   sizeof(x25->dte_facilities));
1501                 release_sock(sk);
1502                 if (rc)
1503                         rc = -EFAULT;
1504                 break;
1505         }
1506
1507         case SIOCX25SDTEFACILITIES: {
1508                 struct x25_dte_facilities dtefacs;
1509                 rc = -EFAULT;
1510                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1511                         break;
1512                 rc = -EINVAL;
1513                 lock_sock(sk);
1514                 if (sk->sk_state != TCP_LISTEN &&
1515                     sk->sk_state != TCP_CLOSE)
1516                         goto out_dtefac_release;
1517                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1518                         goto out_dtefac_release;
1519                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1520                         goto out_dtefac_release;
1521                 x25->dte_facilities = dtefacs;
1522                 rc = 0;
1523 out_dtefac_release:
1524                 release_sock(sk);
1525                 break;
1526         }
1527
1528         case SIOCX25GCALLUSERDATA: {
1529                 lock_sock(sk);
1530                 rc = copy_to_user(argp, &x25->calluserdata,
1531                                   sizeof(x25->calluserdata))
1532                         ? -EFAULT : 0;
1533                 release_sock(sk);
1534                 break;
1535         }
1536
1537         case SIOCX25SCALLUSERDATA: {
1538                 struct x25_calluserdata calluserdata;
1539
1540                 rc = -EFAULT;
1541                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1542                         break;
1543                 rc = -EINVAL;
1544                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1545                         break;
1546                 lock_sock(sk);
1547                 x25->calluserdata = calluserdata;
1548                 release_sock(sk);
1549                 rc = 0;
1550                 break;
1551         }
1552
1553         case SIOCX25GCAUSEDIAG: {
1554                 lock_sock(sk);
1555                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1556                         ? -EFAULT : 0;
1557                 release_sock(sk);
1558                 break;
1559         }
1560
1561         case SIOCX25SCAUSEDIAG: {
1562                 struct x25_causediag causediag;
1563                 rc = -EFAULT;
1564                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1565                         break;
1566                 lock_sock(sk);
1567                 x25->causediag = causediag;
1568                 release_sock(sk);
1569                 rc = 0;
1570                 break;
1571
1572         }
1573
1574         case SIOCX25SCUDMATCHLEN: {
1575                 struct x25_subaddr sub_addr;
1576                 rc = -EINVAL;
1577                 lock_sock(sk);
1578                 if(sk->sk_state != TCP_CLOSE)
1579                         goto out_cud_release;
1580                 rc = -EFAULT;
1581                 if (copy_from_user(&sub_addr, argp,
1582                                    sizeof(sub_addr)))
1583                         goto out_cud_release;
1584                 rc = -EINVAL;
1585                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1586                         goto out_cud_release;
1587                 x25->cudmatchlength = sub_addr.cudmatchlength;
1588                 rc = 0;
1589 out_cud_release:
1590                 release_sock(sk);
1591                 break;
1592         }
1593
1594         case SIOCX25CALLACCPTAPPRV: {
1595                 rc = -EINVAL;
1596                 lock_sock(sk);
1597                 if (sk->sk_state == TCP_CLOSE) {
1598                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1599                         rc = 0;
1600                 }
1601                 release_sock(sk);
1602                 break;
1603         }
1604
1605         case SIOCX25SENDCALLACCPT:  {
1606                 rc = -EINVAL;
1607                 lock_sock(sk);
1608                 if (sk->sk_state != TCP_ESTABLISHED)
1609                         goto out_sendcallaccpt_release;
1610                 /* must call accptapprv above */
1611                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1612                         goto out_sendcallaccpt_release;
1613                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1614                 x25->state = X25_STATE_3;
1615                 rc = 0;
1616 out_sendcallaccpt_release:
1617                 release_sock(sk);
1618                 break;
1619         }
1620
1621         default:
1622                 rc = -ENOIOCTLCMD;
1623                 break;
1624         }
1625
1626         return rc;
1627 }
1628
1629 static const struct net_proto_family x25_family_ops = {
1630         .family =       AF_X25,
1631         .create =       x25_create,
1632         .owner  =       THIS_MODULE,
1633 };
1634
1635 #ifdef CONFIG_COMPAT
1636 static int compat_x25_subscr_ioctl(unsigned int cmd,
1637                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1638 {
1639         struct compat_x25_subscrip_struct x25_subscr;
1640         struct x25_neigh *nb;
1641         struct net_device *dev;
1642         int rc = -EINVAL;
1643
1644         rc = -EFAULT;
1645         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1646                 goto out;
1647
1648         rc = -EINVAL;
1649         dev = x25_dev_get(x25_subscr.device);
1650         if (dev == NULL)
1651                 goto out;
1652
1653         nb = x25_get_neigh(dev);
1654         if (nb == NULL)
1655                 goto out_dev_put;
1656
1657         dev_put(dev);
1658
1659         if (cmd == SIOCX25GSUBSCRIP) {
1660                 read_lock_bh(&x25_neigh_list_lock);
1661                 x25_subscr.extended = nb->extended;
1662                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1663                 read_unlock_bh(&x25_neigh_list_lock);
1664                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1665                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1666         } else {
1667                 rc = -EINVAL;
1668                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1669                         rc = 0;
1670                         write_lock_bh(&x25_neigh_list_lock);
1671                         nb->extended = x25_subscr.extended;
1672                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1673                         write_unlock_bh(&x25_neigh_list_lock);
1674                 }
1675         }
1676         x25_neigh_put(nb);
1677 out:
1678         return rc;
1679 out_dev_put:
1680         dev_put(dev);
1681         goto out;
1682 }
1683
1684 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1685                                 unsigned long arg)
1686 {
1687         void __user *argp = compat_ptr(arg);
1688         int rc = -ENOIOCTLCMD;
1689
1690         switch(cmd) {
1691         case TIOCOUTQ:
1692         case TIOCINQ:
1693                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1694                 break;
1695         case SIOCGIFADDR:
1696         case SIOCSIFADDR:
1697         case SIOCGIFDSTADDR:
1698         case SIOCSIFDSTADDR:
1699         case SIOCGIFBRDADDR:
1700         case SIOCSIFBRDADDR:
1701         case SIOCGIFNETMASK:
1702         case SIOCSIFNETMASK:
1703         case SIOCGIFMETRIC:
1704         case SIOCSIFMETRIC:
1705                 rc = -EINVAL;
1706                 break;
1707         case SIOCADDRT:
1708         case SIOCDELRT:
1709                 rc = -EPERM;
1710                 if (!capable(CAP_NET_ADMIN))
1711                         break;
1712                 rc = x25_route_ioctl(cmd, argp);
1713                 break;
1714         case SIOCX25GSUBSCRIP:
1715                 rc = compat_x25_subscr_ioctl(cmd, argp);
1716                 break;
1717         case SIOCX25SSUBSCRIP:
1718                 rc = -EPERM;
1719                 if (!capable(CAP_NET_ADMIN))
1720                         break;
1721                 rc = compat_x25_subscr_ioctl(cmd, argp);
1722                 break;
1723         case SIOCX25GFACILITIES:
1724         case SIOCX25SFACILITIES:
1725         case SIOCX25GDTEFACILITIES:
1726         case SIOCX25SDTEFACILITIES:
1727         case SIOCX25GCALLUSERDATA:
1728         case SIOCX25SCALLUSERDATA:
1729         case SIOCX25GCAUSEDIAG:
1730         case SIOCX25SCAUSEDIAG:
1731         case SIOCX25SCUDMATCHLEN:
1732         case SIOCX25CALLACCPTAPPRV:
1733         case SIOCX25SENDCALLACCPT:
1734                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1735                 break;
1736         default:
1737                 rc = -ENOIOCTLCMD;
1738                 break;
1739         }
1740         return rc;
1741 }
1742 #endif
1743
1744 static const struct proto_ops x25_proto_ops = {
1745         .family =       AF_X25,
1746         .owner =        THIS_MODULE,
1747         .release =      x25_release,
1748         .bind =         x25_bind,
1749         .connect =      x25_connect,
1750         .socketpair =   sock_no_socketpair,
1751         .accept =       x25_accept,
1752         .getname =      x25_getname,
1753         .poll =         datagram_poll,
1754         .ioctl =        x25_ioctl,
1755 #ifdef CONFIG_COMPAT
1756         .compat_ioctl = compat_x25_ioctl,
1757 #endif
1758         .gettstamp =    sock_gettstamp,
1759         .listen =       x25_listen,
1760         .shutdown =     sock_no_shutdown,
1761         .setsockopt =   x25_setsockopt,
1762         .getsockopt =   x25_getsockopt,
1763         .sendmsg =      x25_sendmsg,
1764         .recvmsg =      x25_recvmsg,
1765         .mmap =         sock_no_mmap,
1766         .sendpage =     sock_no_sendpage,
1767 };
1768
1769 static struct packet_type x25_packet_type __read_mostly = {
1770         .type = cpu_to_be16(ETH_P_X25),
1771         .func = x25_lapb_receive_frame,
1772 };
1773
1774 static struct notifier_block x25_dev_notifier = {
1775         .notifier_call = x25_device_event,
1776 };
1777
1778 void x25_kill_by_neigh(struct x25_neigh *nb)
1779 {
1780         struct sock *s;
1781
1782         write_lock_bh(&x25_list_lock);
1783
1784         sk_for_each(s, &x25_list) {
1785                 if (x25_sk(s)->neighbour == nb) {
1786                         write_unlock_bh(&x25_list_lock);
1787                         lock_sock(s);
1788                         x25_disconnect(s, ENETUNREACH, 0, 0);
1789                         release_sock(s);
1790                         write_lock_bh(&x25_list_lock);
1791                 }
1792         }
1793         write_unlock_bh(&x25_list_lock);
1794
1795         /* Remove any related forwards */
1796         x25_clear_forward_by_dev(nb->dev);
1797 }
1798
1799 static int __init x25_init(void)
1800 {
1801         int rc;
1802
1803         rc = proto_register(&x25_proto, 0);
1804         if (rc)
1805                 goto out;
1806
1807         rc = sock_register(&x25_family_ops);
1808         if (rc)
1809                 goto out_proto;
1810
1811         dev_add_pack(&x25_packet_type);
1812
1813         rc = register_netdevice_notifier(&x25_dev_notifier);
1814         if (rc)
1815                 goto out_sock;
1816
1817         rc = x25_register_sysctl();
1818         if (rc)
1819                 goto out_dev;
1820
1821         rc = x25_proc_init();
1822         if (rc)
1823                 goto out_sysctl;
1824
1825         pr_info("Linux Version 0.2\n");
1826
1827 out:
1828         return rc;
1829 out_sysctl:
1830         x25_unregister_sysctl();
1831 out_dev:
1832         unregister_netdevice_notifier(&x25_dev_notifier);
1833 out_sock:
1834         dev_remove_pack(&x25_packet_type);
1835         sock_unregister(AF_X25);
1836 out_proto:
1837         proto_unregister(&x25_proto);
1838         goto out;
1839 }
1840 module_init(x25_init);
1841
1842 static void __exit x25_exit(void)
1843 {
1844         x25_proc_exit();
1845         x25_link_free();
1846         x25_route_free();
1847
1848         x25_unregister_sysctl();
1849
1850         unregister_netdevice_notifier(&x25_dev_notifier);
1851
1852         dev_remove_pack(&x25_packet_type);
1853
1854         sock_unregister(AF_X25);
1855         proto_unregister(&x25_proto);
1856 }
1857 module_exit(x25_exit);
1858
1859 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1860 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1861 MODULE_LICENSE("GPL");
1862 MODULE_ALIAS_NETPROTO(PF_X25);