net/x25/af_x25.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      X.25 Packet Layer release 002
   4  *
   5  *      This is ALPHA test software. This code may break your machine,
   6  *      randomly fail to work with new releases, misbehave and/or generally
   7  *      screw up. It might even work.
   8  *
   9  *      This code REQUIRES 2.1.15 or higher
  10  *
  11  *      History
  12  *      X.25 001        Jonathan Naylor Started coding.
  13  *      X.25 002        Jonathan Naylor Centralised disconnect handling.
  14  *                                      New timer architecture.
  15  *      2000-03-11      Henner Eisen    MSG_EOR handling more POSIX compliant.
  16  *      2000-03-22      Daniela Squassoni Allowed disabling/enabling of
  17  *                                        facilities negotiation and increased
  18  *                                        the throughput upper limit.
  19  *      2000-08-27      Arnaldo C. Melo s/suser/capable/ + micro cleanups
  20  *      2000-09-04      Henner Eisen    Set sock->state in x25_accept().
  21  *                                      Fixed x25_output() related skb leakage.
  22  *      2000-10-02      Henner Eisen    Made x25_kick() single threaded per socket.
  23  *      2000-10-27      Henner Eisen    MSG_DONTWAIT for fragment allocation.
  24  *      2000-11-14      Henner Eisen    Closing datalink from NETDEV_GOING_DOWN
  25  *      2002-10-06      Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
  26  *                                      x25_proc.c, using seq_file
  27  *      2005-04-02      Shaun Pereira   Selective sub address matching
  28  *                                      with call user data
  29  *      2005-04-15      Shaun Pereira   Fast select with no restriction on
  30  *                                      response
  31  */
  32
  33 #define pr_fmt(fmt) "X25: " fmt
  34
  35 #include <linux/module.h>
  36 #include <linux/capability.h>
  37 #include <linux/errno.h>
  38 #include <linux/kernel.h>
  39 #include <linux/sched/signal.h>
  40 #include <linux/timer.h>
  41 #include <linux/string.h>
  42 #include <linux/net.h>
  43 #include <linux/netdevice.h>
  44 #include <linux/if_arp.h>
  45 #include <linux/skbuff.h>
  46 #include <linux/slab.h>
  47 #include <net/sock.h>
  48 #include <net/tcp_states.h>
  49 #include <linux/uaccess.h>
  50 #include <linux/fcntl.h>
  51 #include <linux/termios.h>      /* For TIOCINQ/OUTQ */
  52 #include <linux/notifier.h>
  53 #include <linux/init.h>
  54 #include <linux/compat.h>
  55 #include <linux/ctype.h>
  56
  57 #include <net/x25.h>
  58 #include <net/compat.h>
  59
  60 int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
  61 int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
  62 int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
  63 int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
  64 int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
  65 int sysctl_x25_forward                 = 0;
  66
  67 HLIST_HEAD(x25_list);
  68 DEFINE_RWLOCK(x25_list_lock);
  69
  70 static const struct proto_ops x25_proto_ops;
  71
  72 static const struct x25_address null_x25_address = {"               "};
  73
  74 #ifdef CONFIG_COMPAT
  75 struct compat_x25_subscrip_struct {
  76         char device[200-sizeof(compat_ulong_t)];
  77         compat_ulong_t global_facil_mask;
  78         compat_uint_t extended;
  79 };
  80 #endif
  81
  82
  83 int x25_parse_address_block(struct sk_buff *skb,
  84                 struct x25_address *called_addr,
  85                 struct x25_address *calling_addr)
  86 {
  87         unsigned char len;
  88         int needed;
  89         int rc;
  90
  91         if (!pskb_may_pull(skb, 1)) {
  92                 /* packet has no address block */
  93                 rc = 0;
  94                 goto empty;
  95         }
  96
  97         len = *skb->data;
  98         needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2;
  99
 100         if (!pskb_may_pull(skb, needed)) {
 101                 /* packet is too short to hold the addresses it claims
 102                    to hold */
 103                 rc = -1;
 104                 goto empty;
 105         }
 106
 107         return x25_addr_ntoa(skb->data, called_addr, calling_addr);
 108
 109 empty:
 110         *called_addr->x25_addr = 0;
 111         *calling_addr->x25_addr = 0;
 112
 113         return rc;
 114 }
 115
 116
 117 int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
 118                   struct x25_address *calling_addr)
 119 {
 120         unsigned int called_len, calling_len;
 121         char *called, *calling;
 122         unsigned int i;
 123
 124         called_len  = (*p >> 0) & 0x0F;
 125         calling_len = (*p >> 4) & 0x0F;
 126
 127         called  = called_addr->x25_addr;
 128         calling = calling_addr->x25_addr;
 129         p++;
 130
 131         for (i = 0; i < (called_len + calling_len); i++) {
 132                 if (i < called_len) {
 133                         if (i % 2 != 0) {
 134                                 *called++ = ((*p >> 0) & 0x0F) + '0';
 135                                 p++;
 136                         } else {
 137                                 *called++ = ((*p >> 4) & 0x0F) + '0';
 138                         }
 139                 } else {
 140                         if (i % 2 != 0) {
 141                                 *calling++ = ((*p >> 0) & 0x0F) + '0';
 142                                 p++;
 143                         } else {
 144                                 *calling++ = ((*p >> 4) & 0x0F) + '0';
 145                         }
 146                 }
 147         }
 148
 149         *called = *calling = '\0';
 150
 151         return 1 + (called_len + calling_len + 1) / 2;
 152 }
 153
 154 int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
 155                   struct x25_address *calling_addr)
 156 {
 157         unsigned int called_len, calling_len;
 158         char *called, *calling;
 159         int i;
 160
 161         called  = called_addr->x25_addr;
 162         calling = calling_addr->x25_addr;
 163
 164         called_len  = strlen(called);
 165         calling_len = strlen(calling);
 166
 167         *p++ = (calling_len << 4) | (called_len << 0);
 168
 169         for (i = 0; i < (called_len + calling_len); i++) {
 170                 if (i < called_len) {
 171                         if (i % 2 != 0) {
 172                                 *p |= (*called++ - '0') << 0;
 173                                 p++;
 174                         } else {
 175                                 *p = 0x00;
 176                                 *p |= (*called++ - '0') << 4;
 177                         }
 178                 } else {
 179                         if (i % 2 != 0) {
 180                                 *p |= (*calling++ - '0') << 0;
 181                                 p++;
 182                         } else {
 183                                 *p = 0x00;
 184                                 *p |= (*calling++ - '0') << 4;
 185                         }
 186                 }
 187         }
 188
 189         return 1 + (called_len + calling_len + 1) / 2;
 190 }
 191
 192 /*
 193  *      Socket removal during an interrupt is now safe.
 194  */
 195 static void x25_remove_socket(struct sock *sk)
 196 {
 197         write_lock_bh(&x25_list_lock);
 198         sk_del_node_init(sk);
 199         write_unlock_bh(&x25_list_lock);
 200 }
 201
 202 /*
 203  *      Kill all bound sockets on a dropped device.
 204  */
 205 static void x25_kill_by_device(struct net_device *dev)
 206 {
 207         struct sock *s;
 208
 209         write_lock_bh(&x25_list_lock);
 210
 211         sk_for_each(s, &x25_list)
 212                 if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
 213                         x25_disconnect(s, ENETUNREACH, 0, 0);
 214
 215         write_unlock_bh(&x25_list_lock);
 216 }
 217
 218 /*
 219  *      Handle device status changes.
 220  */
 221 static int x25_device_event(struct notifier_block *this, unsigned long event,
 222                             void *ptr)
 223 {
 224         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 225         struct x25_neigh *nb;
 226
 227         if (!net_eq(dev_net(dev), &init_net))
 228                 return NOTIFY_DONE;
 229
 230         if (dev->type == ARPHRD_X25
 231 #if IS_ENABLED(CONFIG_LLC)
 232          || dev->type == ARPHRD_ETHER
 233 #endif
 234          ) {
 235                 switch (event) {
 236                 case NETDEV_UP:
 237                         x25_link_device_up(dev);
 238                         break;
 239                 case NETDEV_GOING_DOWN:
 240                         nb = x25_get_neigh(dev);
 241                         if (nb) {
 242                                 x25_terminate_link(nb);
 243                                 x25_neigh_put(nb);
 244                         }
 245                         break;
 246                 case NETDEV_DOWN:
 247                         x25_kill_by_device(dev);
 248                         x25_route_device_down(dev);
 249                         x25_link_device_down(dev);
 250                         break;
 251                 }
 252         }
 253
 254         return NOTIFY_DONE;
 255 }
 256
 257 /*
 258  *      Add a socket to the bound sockets list.
 259  */
 260 static void x25_insert_socket(struct sock *sk)
 261 {
 262         write_lock_bh(&x25_list_lock);
 263         sk_add_node(sk, &x25_list);
 264         write_unlock_bh(&x25_list_lock);
 265 }
 266
 267 /*
 268  *      Find a socket that wants to accept the Call Request we just
 269  *      received. Check the full list for an address/cud match.
 270  *      If no cuds match return the next_best thing, an address match.
 271  *      Note: if a listening socket has cud set it must only get calls
 272  *      with matching cud.
 273  */
 274 static struct sock *x25_find_listener(struct x25_address *addr,
 275                                         struct sk_buff *skb)
 276 {
 277         struct sock *s;
 278         struct sock *next_best;
 279
 280         read_lock_bh(&x25_list_lock);
 281         next_best = NULL;
 282
 283         sk_for_each(s, &x25_list)
 284                 if ((!strcmp(addr->x25_addr,
 285                         x25_sk(s)->source_addr.x25_addr) ||
 286                                 !strcmp(x25_sk(s)->source_addr.x25_addr,
 287                                         null_x25_address.x25_addr)) &&
 288                                         s->sk_state == TCP_LISTEN) {
 289                         /*
 290                          * Found a listening socket, now check the incoming
 291                          * call user data vs this sockets call user data
 292                          */
 293                         if (x25_sk(s)->cudmatchlength > 0 &&
 294                                 skb->len >= x25_sk(s)->cudmatchlength) {
 295                                 if((memcmp(x25_sk(s)->calluserdata.cuddata,
 296                                         skb->data,
 297                                         x25_sk(s)->cudmatchlength)) == 0) {
 298                                         sock_hold(s);
 299                                         goto found;
 300                                  }
 301                         } else
 302                                 next_best = s;
 303                 }
 304         if (next_best) {
 305                 s = next_best;
 306                 sock_hold(s);
 307                 goto found;
 308         }
 309         s = NULL;
 310 found:
 311         read_unlock_bh(&x25_list_lock);
 312         return s;
 313 }
 314
 315 /*
 316  *      Find a connected X.25 socket given my LCI and neighbour.
 317  */
 318 static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 319 {
 320         struct sock *s;
 321
 322         sk_for_each(s, &x25_list)
 323                 if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
 324                         sock_hold(s);
 325                         goto found;
 326                 }
 327         s = NULL;
 328 found:
 329         return s;
 330 }
 331
 332 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 333 {
 334         struct sock *s;
 335
 336         read_lock_bh(&x25_list_lock);
 337         s = __x25_find_socket(lci, nb);
 338         read_unlock_bh(&x25_list_lock);
 339         return s;
 340 }
 341
 342 /*
 343  *      Find a unique LCI for a given device.
 344  */
 345 static unsigned int x25_new_lci(struct x25_neigh *nb)
 346 {
 347         unsigned int lci = 1;
 348         struct sock *sk;
 349
 350         while ((sk = x25_find_socket(lci, nb)) != NULL) {
 351                 sock_put(sk);
 352                 if (++lci == 4096) {
 353                         lci = 0;
 354                         break;
 355                 }
 356                 cond_resched();
 357         }
 358
 359         return lci;
 360 }
 361
 362 /*
 363  *      Deferred destroy.
 364  */
 365 static void __x25_destroy_socket(struct sock *);
 366
 367 /*
 368  *      handler for deferred kills.
 369  */
 370 static void x25_destroy_timer(struct timer_list *t)
 371 {
 372         struct sock *sk = from_timer(sk, t, sk_timer);
 373
 374         x25_destroy_socket_from_timer(sk);
 375 }
 376
 377 /*
 378  *      This is called from user mode and the timers. Thus it protects itself
 379  *      against interrupt users but doesn't worry about being called during
 380  *      work. Once it is removed from the queue no interrupt or bottom half
 381  *      will touch it and we are (fairly 8-) ) safe.
 382  *      Not static as it's used by the timer
 383  */
 384 static void __x25_destroy_socket(struct sock *sk)
 385 {
 386         struct sk_buff *skb;
 387
 388         x25_stop_heartbeat(sk);
 389         x25_stop_timer(sk);
 390
 391         x25_remove_socket(sk);
 392         x25_clear_queues(sk);           /* Flush the queues */
 393
 394         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 395                 if (skb->sk != sk) {            /* A pending connection */
 396                         /*
 397                          * Queue the unaccepted socket for death
 398                          */
 399                         skb->sk->sk_state = TCP_LISTEN;
 400                         sock_set_flag(skb->sk, SOCK_DEAD);
 401                         x25_start_heartbeat(skb->sk);
 402                         x25_sk(skb->sk)->state = X25_STATE_0;
 403                 }
 404
 405                 kfree_skb(skb);
 406         }
 407
 408         if (sk_has_allocations(sk)) {
 409                 /* Defer: outstanding buffers */
 410                 sk->sk_timer.expires  = jiffies + 10 * HZ;
 411                 sk->sk_timer.function = x25_destroy_timer;
 412                 add_timer(&sk->sk_timer);
 413         } else {
 414                 /* drop last reference so sock_put will free */
 415                 __sock_put(sk);
 416         }
 417 }
 418
 419 void x25_destroy_socket_from_timer(struct sock *sk)
 420 {
 421         sock_hold(sk);
 422         bh_lock_sock(sk);
 423         __x25_destroy_socket(sk);
 424         bh_unlock_sock(sk);
 425         sock_put(sk);
 426 }
 427
 428 /*
 429  *      Handling for system calls applied via the various interfaces to a
 430  *      X.25 socket object.
 431  */
 432
 433 static int x25_setsockopt(struct socket *sock, int level, int optname,
 434                           char __user *optval, unsigned int optlen)
 435 {
 436         int opt;
 437         struct sock *sk = sock->sk;
 438         int rc = -ENOPROTOOPT;
 439
 440         if (level != SOL_X25 || optname != X25_QBITINCL)
 441                 goto out;
 442
 443         rc = -EINVAL;
 444         if (optlen < sizeof(int))
 445                 goto out;
 446
 447         rc = -EFAULT;
 448         if (get_user(opt, (int __user *)optval))
 449                 goto out;
 450
 451         if (opt)
 452                 set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 453         else
 454                 clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 455         rc = 0;
 456 out:
 457         return rc;
 458 }
 459
 460 static int x25_getsockopt(struct socket *sock, int level, int optname,
 461                           char __user *optval, int __user *optlen)
 462 {
 463         struct sock *sk = sock->sk;
 464         int val, len, rc = -ENOPROTOOPT;
 465
 466         if (level != SOL_X25 || optname != X25_QBITINCL)
 467                 goto out;
 468
 469         rc = -EFAULT;
 470         if (get_user(len, optlen))
 471                 goto out;
 472
 473         len = min_t(unsigned int, len, sizeof(int));
 474
 475         rc = -EINVAL;
 476         if (len < 0)
 477                 goto out;
 478
 479         rc = -EFAULT;
 480         if (put_user(len, optlen))
 481                 goto out;
 482
 483         val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 484         rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
 485 out:
 486         return rc;
 487 }
 488
 489 static int x25_listen(struct socket *sock, int backlog)
 490 {
 491         struct sock *sk = sock->sk;
 492         int rc = -EOPNOTSUPP;
 493
 494         lock_sock(sk);
 495         if (sk->sk_state != TCP_LISTEN) {
 496                 memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 497                 sk->sk_max_ack_backlog = backlog;
 498                 sk->sk_state           = TCP_LISTEN;
 499                 rc = 0;
 500         }
 501         release_sock(sk);
 502
 503         return rc;
 504 }
 505
 506 static struct proto x25_proto = {
 507         .name     = "X25",
 508         .owner    = THIS_MODULE,
 509         .obj_size = sizeof(struct x25_sock),
 510 };
 511
 512 static struct sock *x25_alloc_socket(struct net *net, int kern)
 513 {
 514         struct x25_sock *x25;
 515         struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 516
 517         if (!sk)
 518                 goto out;
 519
 520         sock_init_data(NULL, sk);
 521
 522         x25 = x25_sk(sk);
 523         skb_queue_head_init(&x25->ack_queue);
 524         skb_queue_head_init(&x25->fragment_queue);
 525         skb_queue_head_init(&x25->interrupt_in_queue);
 526         skb_queue_head_init(&x25->interrupt_out_queue);
 527 out:
 528         return sk;
 529 }
 530
 531 static int x25_create(struct net *net, struct socket *sock, int protocol,
 532                       int kern)
 533 {
 534         struct sock *sk;
 535         struct x25_sock *x25;
 536         int rc = -EAFNOSUPPORT;
 537
 538         if (!net_eq(net, &init_net))
 539                 goto out;
 540
 541         rc = -ESOCKTNOSUPPORT;
 542         if (sock->type != SOCK_SEQPACKET)
 543                 goto out;
 544
 545         rc = -EINVAL;
 546         if (protocol)
 547                 goto out;
 548
 549         rc = -ENOMEM;
 550         if ((sk = x25_alloc_socket(net, kern)) == NULL)
 551                 goto out;
 552
 553         x25 = x25_sk(sk);
 554
 555         sock_init_data(sock, sk);
 556
 557         x25_init_timers(sk);
 558
 559         sock->ops    = &x25_proto_ops;
 560         sk->sk_protocol = protocol;
 561         sk->sk_backlog_rcv = x25_backlog_rcv;
 562
 563         x25->t21   = sysctl_x25_call_request_timeout;
 564         x25->t22   = sysctl_x25_reset_request_timeout;
 565         x25->t23   = sysctl_x25_clear_request_timeout;
 566         x25->t2    = sysctl_x25_ack_holdback_timeout;
 567         x25->state = X25_STATE_0;
 568         x25->cudmatchlength = 0;
 569         set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);     /* normally no cud  */
 570                                                         /* on call accept   */
 571
 572         x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 573         x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 574         x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 575         x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 576         x25->facilities.throughput  = 0;        /* by default don't negotiate
 577                                                    throughput */
 578         x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 579         x25->dte_facilities.calling_len = 0;
 580         x25->dte_facilities.called_len = 0;
 581         memset(x25->dte_facilities.called_ae, '\0',
 582                         sizeof(x25->dte_facilities.called_ae));
 583         memset(x25->dte_facilities.calling_ae, '\0',
 584                         sizeof(x25->dte_facilities.calling_ae));
 585
 586         rc = 0;
 587 out:
 588         return rc;
 589 }
 590
 591 static struct sock *x25_make_new(struct sock *osk)
 592 {
 593         struct sock *sk = NULL;
 594         struct x25_sock *x25, *ox25;
 595
 596         if (osk->sk_type != SOCK_SEQPACKET)
 597                 goto out;
 598
 599         if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 600                 goto out;
 601
 602         x25 = x25_sk(sk);
 603
 604         sk->sk_type        = osk->sk_type;
 605         sk->sk_priority    = osk->sk_priority;
 606         sk->sk_protocol    = osk->sk_protocol;
 607         sk->sk_rcvbuf      = osk->sk_rcvbuf;
 608         sk->sk_sndbuf      = osk->sk_sndbuf;
 609         sk->sk_state       = TCP_ESTABLISHED;
 610         sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 611         sock_copy_flags(sk, osk);
 612
 613         ox25 = x25_sk(osk);
 614         x25->t21        = ox25->t21;
 615         x25->t22        = ox25->t22;
 616         x25->t23        = ox25->t23;
 617         x25->t2         = ox25->t2;
 618         x25->flags      = ox25->flags;
 619         x25->facilities = ox25->facilities;
 620         x25->dte_facilities = ox25->dte_facilities;
 621         x25->cudmatchlength = ox25->cudmatchlength;
 622
 623         clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 624         x25_init_timers(sk);
 625 out:
 626         return sk;
 627 }
 628
 629 static int x25_release(struct socket *sock)
 630 {
 631         struct sock *sk = sock->sk;
 632         struct x25_sock *x25;
 633
 634         if (!sk)
 635                 return 0;
 636
 637         x25 = x25_sk(sk);
 638
 639         sock_hold(sk);
 640         lock_sock(sk);
 641         switch (x25->state) {
 642
 643                 case X25_STATE_0:
 644                 case X25_STATE_2:
 645                         x25_disconnect(sk, 0, 0, 0);
 646                         __x25_destroy_socket(sk);
 647                         goto out;
 648
 649                 case X25_STATE_1:
 650                 case X25_STATE_3:
 651                 case X25_STATE_4:
 652                         x25_clear_queues(sk);
 653                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 654                         x25_start_t23timer(sk);
 655                         x25->state = X25_STATE_2;
 656                         sk->sk_state    = TCP_CLOSE;
 657                         sk->sk_shutdown |= SEND_SHUTDOWN;
 658                         sk->sk_state_change(sk);
 659                         sock_set_flag(sk, SOCK_DEAD);
 660                         sock_set_flag(sk, SOCK_DESTROY);
 661                         break;
 662         }
 663
 664         sock_orphan(sk);
 665 out:
 666         release_sock(sk);
 667         sock_put(sk);
 668         return 0;
 669 }
 670
 671 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 672 {
 673         struct sock *sk = sock->sk;
 674         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 675         int len, i, rc = 0;
 676
 677         if (addr_len != sizeof(struct sockaddr_x25) ||
 678             addr->sx25_family != AF_X25 ||
 679             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) {
 680                 rc = -EINVAL;
 681                 goto out;
 682         }
 683
 684         /* check for the null_x25_address */
 685         if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
 686
 687                 len = strlen(addr->sx25_addr.x25_addr);
 688                 for (i = 0; i < len; i++) {
 689                         if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 690                                 rc = -EINVAL;
 691                                 goto out;
 692                         }
 693                 }
 694         }
 695
 696         lock_sock(sk);
 697         if (sock_flag(sk, SOCK_ZAPPED)) {
 698                 x25_sk(sk)->source_addr = addr->sx25_addr;
 699                 x25_insert_socket(sk);
 700                 sock_reset_flag(sk, SOCK_ZAPPED);
 701         } else {
 702                 rc = -EINVAL;
 703         }
 704         release_sock(sk);
 705         SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
 706 out:
 707         return rc;
 708 }
 709
 710 static int x25_wait_for_connection_establishment(struct sock *sk)
 711 {
 712         DECLARE_WAITQUEUE(wait, current);
 713         int rc;
 714
 715         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 716         for (;;) {
 717                 __set_current_state(TASK_INTERRUPTIBLE);
 718                 rc = -ERESTARTSYS;
 719                 if (signal_pending(current))
 720                         break;
 721                 rc = sock_error(sk);
 722                 if (rc) {
 723                         sk->sk_socket->state = SS_UNCONNECTED;
 724                         break;
 725                 }
 726                 rc = 0;
 727                 if (sk->sk_state != TCP_ESTABLISHED) {
 728                         release_sock(sk);
 729                         schedule();
 730                         lock_sock(sk);
 731                 } else
 732                         break;
 733         }
 734         __set_current_state(TASK_RUNNING);
 735         remove_wait_queue(sk_sleep(sk), &wait);
 736         return rc;
 737 }
 738
 739 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
 740                        int addr_len, int flags)
 741 {
 742         struct sock *sk = sock->sk;
 743         struct x25_sock *x25 = x25_sk(sk);
 744         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 745         struct x25_route *rt;
 746         int rc = 0;
 747
 748         lock_sock(sk);
 749         if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 750                 sock->state = SS_CONNECTED;
 751                 goto out; /* Connect completed during a ERESTARTSYS event */
 752         }
 753
 754         rc = -ECONNREFUSED;
 755         if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 756                 sock->state = SS_UNCONNECTED;
 757                 goto out;
 758         }
 759
 760         rc = -EISCONN;  /* No reconnect on a seqpacket socket */
 761         if (sk->sk_state == TCP_ESTABLISHED)
 762                 goto out;
 763
 764         rc = -EALREADY; /* Do nothing if call is already in progress */
 765         if (sk->sk_state == TCP_SYN_SENT)
 766                 goto out;
 767
 768         sk->sk_state   = TCP_CLOSE;
 769         sock->state = SS_UNCONNECTED;
 770
 771         rc = -EINVAL;
 772         if (addr_len != sizeof(struct sockaddr_x25) ||
 773             addr->sx25_family != AF_X25 ||
 774             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN)
 775                 goto out;
 776
 777         rc = -ENETUNREACH;
 778         rt = x25_get_route(&addr->sx25_addr);
 779         if (!rt)
 780                 goto out;
 781
 782         x25->neighbour = x25_get_neigh(rt->dev);
 783         if (!x25->neighbour)
 784                 goto out_put_route;
 785
 786         x25_limit_facilities(&x25->facilities, x25->neighbour);
 787
 788         x25->lci = x25_new_lci(x25->neighbour);
 789         if (!x25->lci)
 790                 goto out_put_neigh;
 791
 792         rc = -EINVAL;
 793         if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 794                 goto out_put_neigh;
 795
 796         if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 797                 memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 798
 799         x25->dest_addr = addr->sx25_addr;
 800
 801         /* Move to connecting socket, start sending Connect Requests */
 802         sock->state   = SS_CONNECTING;
 803         sk->sk_state  = TCP_SYN_SENT;
 804
 805         x25->state = X25_STATE_1;
 806
 807         x25_write_internal(sk, X25_CALL_REQUEST);
 808
 809         x25_start_heartbeat(sk);
 810         x25_start_t21timer(sk);
 811
 812         /* Now the loop */
 813         rc = -EINPROGRESS;
 814         if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 815                 goto out;
 816
 817         rc = x25_wait_for_connection_establishment(sk);
 818         if (rc)
 819                 goto out_put_neigh;
 820
 821         sock->state = SS_CONNECTED;
 822         rc = 0;
 823 out_put_neigh:
 824         if (rc && x25->neighbour) {
 825                 read_lock_bh(&x25_list_lock);
 826                 x25_neigh_put(x25->neighbour);
 827                 x25->neighbour = NULL;
 828                 read_unlock_bh(&x25_list_lock);
 829                 x25->state = X25_STATE_0;
 830         }
 831 out_put_route:
 832         x25_route_put(rt);
 833 out:
 834         release_sock(sk);
 835         return rc;
 836 }
 837
 838 static int x25_wait_for_data(struct sock *sk, long timeout)
 839 {
 840         DECLARE_WAITQUEUE(wait, current);
 841         int rc = 0;
 842
 843         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 844         for (;;) {
 845                 __set_current_state(TASK_INTERRUPTIBLE);
 846                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 847                         break;
 848                 rc = -ERESTARTSYS;
 849                 if (signal_pending(current))
 850                         break;
 851                 rc = -EAGAIN;
 852                 if (!timeout)
 853                         break;
 854                 rc = 0;
 855                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 856                         release_sock(sk);
 857                         timeout = schedule_timeout(timeout);
 858                         lock_sock(sk);
 859                 } else
 860                         break;
 861         }
 862         __set_current_state(TASK_RUNNING);
 863         remove_wait_queue(sk_sleep(sk), &wait);
 864         return rc;
 865 }
 866
 867 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 868                       bool kern)
 869 {
 870         struct sock *sk = sock->sk;
 871         struct sock *newsk;
 872         struct sk_buff *skb;
 873         int rc = -EINVAL;
 874
 875         if (!sk)
 876                 goto out;
 877
 878         rc = -EOPNOTSUPP;
 879         if (sk->sk_type != SOCK_SEQPACKET)
 880                 goto out;
 881
 882         lock_sock(sk);
 883         rc = -EINVAL;
 884         if (sk->sk_state != TCP_LISTEN)
 885                 goto out2;
 886
 887         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 888         if (rc)
 889                 goto out2;
 890         skb = skb_dequeue(&sk->sk_receive_queue);
 891         rc = -EINVAL;
 892         if (!skb->sk)
 893                 goto out2;
 894         newsk            = skb->sk;
 895         sock_graft(newsk, newsock);
 896
 897         /* Now attach up the new socket */
 898         skb->sk = NULL;
 899         kfree_skb(skb);
 900         sk->sk_ack_backlog--;
 901         newsock->state = SS_CONNECTED;
 902         rc = 0;
 903 out2:
 904         release_sock(sk);
 905 out:
 906         return rc;
 907 }
 908
 909 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 910                        int peer)
 911 {
 912         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 913         struct sock *sk = sock->sk;
 914         struct x25_sock *x25 = x25_sk(sk);
 915         int rc = 0;
 916
 917         if (peer) {
 918                 if (sk->sk_state != TCP_ESTABLISHED) {
 919                         rc = -ENOTCONN;
 920                         goto out;
 921                 }
 922                 sx25->sx25_addr = x25->dest_addr;
 923         } else
 924                 sx25->sx25_addr = x25->source_addr;
 925
 926         sx25->sx25_family = AF_X25;
 927         rc = sizeof(*sx25);
 928
 929 out:
 930         return rc;
 931 }
 932
 933 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 934                         unsigned int lci)
 935 {
 936         struct sock *sk;
 937         struct sock *make;
 938         struct x25_sock *makex25;
 939         struct x25_address source_addr, dest_addr;
 940         struct x25_facilities facilities;
 941         struct x25_dte_facilities dte_facilities;
 942         int len, addr_len, rc;
 943
 944         /*
 945          *      Remove the LCI and frame type.
 946          */
 947         skb_pull(skb, X25_STD_MIN_LEN);
 948
 949         /*
 950          *      Extract the X.25 addresses and convert them to ASCII strings,
 951          *      and remove them.
 952          *
 953          *      Address block is mandatory in call request packets
 954          */
 955         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 956         if (addr_len <= 0)
 957                 goto out_clear_request;
 958         skb_pull(skb, addr_len);
 959
 960         /*
 961          *      Get the length of the facilities, skip past them for the moment
 962          *      get the call user data because this is needed to determine
 963          *      the correct listener
 964          *
 965          *      Facilities length is mandatory in call request packets
 966          */
 967         if (!pskb_may_pull(skb, 1))
 968                 goto out_clear_request;
 969         len = skb->data[0] + 1;
 970         if (!pskb_may_pull(skb, len))
 971                 goto out_clear_request;
 972         skb_pull(skb,len);
 973
 974         /*
 975          *      Ensure that the amount of call user data is valid.
 976          */
 977         if (skb->len > X25_MAX_CUD_LEN)
 978                 goto out_clear_request;
 979
 980         /*
 981          *      Get all the call user data so it can be used in
 982          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 983          */
 984         if (!pskb_may_pull(skb, skb->len))
 985                 goto out_clear_request;
 986
 987         /*
 988          *      Find a listener for the particular address/cud pair.
 989          */
 990         sk = x25_find_listener(&source_addr,skb);
 991         skb_push(skb,len);
 992
 993         if (sk != NULL && sk_acceptq_is_full(sk)) {
 994                 goto out_sock_put;
 995         }
 996
 997         /*
 998          *      We dont have any listeners for this incoming call.
 999          *      Try forwarding it.
1000          */
1001         if (sk == NULL) {
1002                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
1003                 if (sysctl_x25_forward &&
1004                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1005                 {
1006                         /* Call was forwarded, dont process it any more */
1007                         kfree_skb(skb);
1008                         rc = 1;
1009                         goto out;
1010                 } else {
1011                         /* No listeners, can't forward, clear the call */
1012                         goto out_clear_request;
1013                 }
1014         }
1015
1016         /*
1017          *      Try to reach a compromise on the requested facilities.
1018          */
1019         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1020         if (len == -1)
1021                 goto out_sock_put;
1022
1023         /*
1024          * current neighbour/link might impose additional limits
1025          * on certain facilties
1026          */
1027
1028         x25_limit_facilities(&facilities, nb);
1029
1030         /*
1031          *      Try to create a new socket.
1032          */
1033         make = x25_make_new(sk);
1034         if (!make)
1035                 goto out_sock_put;
1036
1037         /*
1038          *      Remove the facilities
1039          */
1040         skb_pull(skb, len);
1041
1042         skb->sk     = make;
1043         make->sk_state = TCP_ESTABLISHED;
1044
1045         makex25 = x25_sk(make);
1046         makex25->lci           = lci;
1047         makex25->dest_addr     = dest_addr;
1048         makex25->source_addr   = source_addr;
1049         x25_neigh_hold(nb);
1050         makex25->neighbour     = nb;
1051         makex25->facilities    = facilities;
1052         makex25->dte_facilities= dte_facilities;
1053         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1054         /* ensure no reverse facil on accept */
1055         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1056         /* ensure no calling address extension on accept */
1057         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1058         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1059
1060         /* Normally all calls are accepted immediately */
1061         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1062                 x25_write_internal(make, X25_CALL_ACCEPTED);
1063                 makex25->state = X25_STATE_3;
1064         }
1065
1066         /*
1067          *      Incoming Call User Data.
1068          */
1069         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1070         makex25->calluserdata.cudlength = skb->len;
1071
1072         sk->sk_ack_backlog++;
1073
1074         x25_insert_socket(make);
1075
1076         skb_queue_head(&sk->sk_receive_queue, skb);
1077
1078         x25_start_heartbeat(make);
1079
1080         if (!sock_flag(sk, SOCK_DEAD))
1081                 sk->sk_data_ready(sk);
1082         rc = 1;
1083         sock_put(sk);
1084 out:
1085         return rc;
1086 out_sock_put:
1087         sock_put(sk);
1088 out_clear_request:
1089         rc = 0;
1090         x25_transmit_clear_request(nb, lci, 0x01);
1091         goto out;
1092 }
1093
1094 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1095 {
1096         struct sock *sk = sock->sk;
1097         struct x25_sock *x25 = x25_sk(sk);
1098         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1099         struct sockaddr_x25 sx25;
1100         struct sk_buff *skb;
1101         unsigned char *asmptr;
1102         int noblock = msg->msg_flags & MSG_DONTWAIT;
1103         size_t size;
1104         int qbit = 0, rc = -EINVAL;
1105
1106         lock_sock(sk);
1107         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1108                 goto out;
1109
1110         /* we currently don't support segmented records at the user interface */
1111         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1112                 goto out;
1113
1114         rc = -EADDRNOTAVAIL;
1115         if (sock_flag(sk, SOCK_ZAPPED))
1116                 goto out;
1117
1118         rc = -EPIPE;
1119         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1120                 send_sig(SIGPIPE, current, 0);
1121                 goto out;
1122         }
1123
1124         rc = -ENETUNREACH;
1125         if (!x25->neighbour)
1126                 goto out;
1127
1128         if (usx25) {
1129                 rc = -EINVAL;
1130                 if (msg->msg_namelen < sizeof(sx25))
1131                         goto out;
1132                 memcpy(&sx25, usx25, sizeof(sx25));
1133                 rc = -EISCONN;
1134                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1135                         goto out;
1136                 rc = -EINVAL;
1137                 if (sx25.sx25_family != AF_X25)
1138                         goto out;
1139         } else {
1140                 /*
1141                  *      FIXME 1003.1g - if the socket is like this because
1142                  *      it has become closed (not started closed) we ought
1143                  *      to SIGPIPE, EPIPE;
1144                  */
1145                 rc = -ENOTCONN;
1146                 if (sk->sk_state != TCP_ESTABLISHED)
1147                         goto out;
1148
1149                 sx25.sx25_family = AF_X25;
1150                 sx25.sx25_addr   = x25->dest_addr;
1151         }
1152
1153         /* Sanity check the packet size */
1154         if (len > 65535) {
1155                 rc = -EMSGSIZE;
1156                 goto out;
1157         }
1158
1159         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1160
1161         /* Build a packet */
1162         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1163
1164         if ((msg->msg_flags & MSG_OOB) && len > 32)
1165                 len = 32;
1166
1167         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1168
1169         release_sock(sk);
1170         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1171         lock_sock(sk);
1172         if (!skb)
1173                 goto out;
1174         X25_SKB_CB(skb)->flags = msg->msg_flags;
1175
1176         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1177
1178         /*
1179          *      Put the data on the end
1180          */
1181         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1182
1183         skb_reset_transport_header(skb);
1184         skb_put(skb, len);
1185
1186         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1187         if (rc)
1188                 goto out_kfree_skb;
1189
1190         /*
1191          *      If the Q BIT Include socket option is in force, the first
1192          *      byte of the user data is the logical value of the Q Bit.
1193          */
1194         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1195                 if (!pskb_may_pull(skb, 1))
1196                         goto out_kfree_skb;
1197
1198                 qbit = skb->data[0];
1199                 skb_pull(skb, 1);
1200         }
1201
1202         /*
1203          *      Push down the X.25 header
1204          */
1205         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1206
1207         if (msg->msg_flags & MSG_OOB) {
1208                 if (x25->neighbour->extended) {
1209                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1210                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1211                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1212                         *asmptr++ = X25_INTERRUPT;
1213                 } else {
1214                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1215                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1216                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1217                         *asmptr++ = X25_INTERRUPT;
1218                 }
1219         } else {
1220                 if (x25->neighbour->extended) {
1221                         /* Build an Extended X.25 header */
1222                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1223                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1224                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1225                         *asmptr++ = X25_DATA;
1226                         *asmptr++ = X25_DATA;
1227                 } else {
1228                         /* Build an Standard X.25 header */
1229                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1230                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1231                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1232                         *asmptr++ = X25_DATA;
1233                 }
1234
1235                 if (qbit)
1236                         skb->data[0] |= X25_Q_BIT;
1237         }
1238
1239         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1240         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1241
1242         rc = -ENOTCONN;
1243         if (sk->sk_state != TCP_ESTABLISHED)
1244                 goto out_kfree_skb;
1245
1246         if (msg->msg_flags & MSG_OOB)
1247                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1248         else {
1249                 rc = x25_output(sk, skb);
1250                 len = rc;
1251                 if (rc < 0)
1252                         kfree_skb(skb);
1253                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1254                         len++;
1255         }
1256
1257         x25_kick(sk);
1258         rc = len;
1259 out:
1260         release_sock(sk);
1261         return rc;
1262 out_kfree_skb:
1263         kfree_skb(skb);
1264         goto out;
1265 }
1266
1267
1268 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1269                        int flags)
1270 {
1271         struct sock *sk = sock->sk;
1272         struct x25_sock *x25 = x25_sk(sk);
1273         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1274         size_t copied;
1275         int qbit, header_len;
1276         struct sk_buff *skb;
1277         unsigned char *asmptr;
1278         int rc = -ENOTCONN;
1279
1280         lock_sock(sk);
1281
1282         if (x25->neighbour == NULL)
1283                 goto out;
1284
1285         header_len = x25->neighbour->extended ?
1286                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1287
1288         /*
1289          * This works for seqpacket too. The receiver has ordered the queue for
1290          * us! We do one quick check first though
1291          */
1292         if (sk->sk_state != TCP_ESTABLISHED)
1293                 goto out;
1294
1295         if (flags & MSG_OOB) {
1296                 rc = -EINVAL;
1297                 if (sock_flag(sk, SOCK_URGINLINE) ||
1298                     !skb_peek(&x25->interrupt_in_queue))
1299                         goto out;
1300
1301                 skb = skb_dequeue(&x25->interrupt_in_queue);
1302
1303                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1304                         goto out_free_dgram;
1305
1306                 skb_pull(skb, X25_STD_MIN_LEN);
1307
1308                 /*
1309                  *      No Q bit information on Interrupt data.
1310                  */
1311                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1312                         asmptr  = skb_push(skb, 1);
1313                         *asmptr = 0x00;
1314                 }
1315
1316                 msg->msg_flags |= MSG_OOB;
1317         } else {
1318                 /* Now we can treat all alike */
1319                 release_sock(sk);
1320                 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1321                                         flags & MSG_DONTWAIT, &rc);
1322                 lock_sock(sk);
1323                 if (!skb)
1324                         goto out;
1325
1326                 if (!pskb_may_pull(skb, header_len))
1327                         goto out_free_dgram;
1328
1329                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1330
1331                 skb_pull(skb, header_len);
1332
1333                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1334                         asmptr  = skb_push(skb, 1);
1335                         *asmptr = qbit;
1336                 }
1337         }
1338
1339         skb_reset_transport_header(skb);
1340         copied = skb->len;
1341
1342         if (copied > size) {
1343                 copied = size;
1344                 msg->msg_flags |= MSG_TRUNC;
1345         }
1346
1347         /* Currently, each datagram always contains a complete record */
1348         msg->msg_flags |= MSG_EOR;
1349
1350         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1351         if (rc)
1352                 goto out_free_dgram;
1353
1354         if (sx25) {
1355                 sx25->sx25_family = AF_X25;
1356                 sx25->sx25_addr   = x25->dest_addr;
1357                 msg->msg_namelen = sizeof(*sx25);
1358         }
1359
1360         x25_check_rbuf(sk);
1361         rc = copied;
1362 out_free_dgram:
1363         skb_free_datagram(sk, skb);
1364 out:
1365         release_sock(sk);
1366         return rc;
1367 }
1368
1369
1370 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1371 {
1372         struct sock *sk = sock->sk;
1373         struct x25_sock *x25 = x25_sk(sk);
1374         void __user *argp = (void __user *)arg;
1375         int rc;
1376
1377         switch (cmd) {
1378         case TIOCOUTQ: {
1379                 int amount;
1380
1381                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1382                 if (amount < 0)
1383                         amount = 0;
1384                 rc = put_user(amount, (unsigned int __user *)argp);
1385                 break;
1386         }
1387
1388         case TIOCINQ: {
1389                 struct sk_buff *skb;
1390                 int amount = 0;
1391                 /*
1392                  * These two are safe on a single CPU system as
1393                  * only user tasks fiddle here
1394                  */
1395                 lock_sock(sk);
1396                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1397                         amount = skb->len;
1398                 release_sock(sk);
1399                 rc = put_user(amount, (unsigned int __user *)argp);
1400                 break;
1401         }
1402
1403         case SIOCGIFADDR:
1404         case SIOCSIFADDR:
1405         case SIOCGIFDSTADDR:
1406         case SIOCSIFDSTADDR:
1407         case SIOCGIFBRDADDR:
1408         case SIOCSIFBRDADDR:
1409         case SIOCGIFNETMASK:
1410         case SIOCSIFNETMASK:
1411         case SIOCGIFMETRIC:
1412         case SIOCSIFMETRIC:
1413                 rc = -EINVAL;
1414                 break;
1415         case SIOCADDRT:
1416         case SIOCDELRT:
1417                 rc = -EPERM;
1418                 if (!capable(CAP_NET_ADMIN))
1419                         break;
1420                 rc = x25_route_ioctl(cmd, argp);
1421                 break;
1422         case SIOCX25GSUBSCRIP:
1423                 rc = x25_subscr_ioctl(cmd, argp);
1424                 break;
1425         case SIOCX25SSUBSCRIP:
1426                 rc = -EPERM;
1427                 if (!capable(CAP_NET_ADMIN))
1428                         break;
1429                 rc = x25_subscr_ioctl(cmd, argp);
1430                 break;
1431         case SIOCX25GFACILITIES: {
1432                 lock_sock(sk);
1433                 rc = copy_to_user(argp, &x25->facilities,
1434                                   sizeof(x25->facilities))
1435                         ? -EFAULT : 0;
1436                 release_sock(sk);
1437                 break;
1438         }
1439
1440         case SIOCX25SFACILITIES: {
1441                 struct x25_facilities facilities;
1442                 rc = -EFAULT;
1443                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1444                         break;
1445                 rc = -EINVAL;
1446                 lock_sock(sk);
1447                 if (sk->sk_state != TCP_LISTEN &&
1448                     sk->sk_state != TCP_CLOSE)
1449                         goto out_fac_release;
1450                 if (facilities.pacsize_in < X25_PS16 ||
1451                     facilities.pacsize_in > X25_PS4096)
1452                         goto out_fac_release;
1453                 if (facilities.pacsize_out < X25_PS16 ||
1454                     facilities.pacsize_out > X25_PS4096)
1455                         goto out_fac_release;
1456                 if (facilities.winsize_in < 1 ||
1457                     facilities.winsize_in > 127)
1458                         goto out_fac_release;
1459                 if (facilities.throughput) {
1460                         int out = facilities.throughput & 0xf0;
1461                         int in  = facilities.throughput & 0x0f;
1462                         if (!out)
1463                                 facilities.throughput |=
1464                                         X25_DEFAULT_THROUGHPUT << 4;
1465                         else if (out < 0x30 || out > 0xD0)
1466                                 goto out_fac_release;
1467                         if (!in)
1468                                 facilities.throughput |=
1469                                         X25_DEFAULT_THROUGHPUT;
1470                         else if (in < 0x03 || in > 0x0D)
1471                                 goto out_fac_release;
1472                 }
1473                 if (facilities.reverse &&
1474                     (facilities.reverse & 0x81) != 0x81)
1475                         goto out_fac_release;
1476                 x25->facilities = facilities;
1477                 rc = 0;
1478 out_fac_release:
1479                 release_sock(sk);
1480                 break;
1481         }
1482
1483         case SIOCX25GDTEFACILITIES: {
1484                 lock_sock(sk);
1485                 rc = copy_to_user(argp, &x25->dte_facilities,
1486                                   sizeof(x25->dte_facilities));
1487                 release_sock(sk);
1488                 if (rc)
1489                         rc = -EFAULT;
1490                 break;
1491         }
1492
1493         case SIOCX25SDTEFACILITIES: {
1494                 struct x25_dte_facilities dtefacs;
1495                 rc = -EFAULT;
1496                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1497                         break;
1498                 rc = -EINVAL;
1499                 lock_sock(sk);
1500                 if (sk->sk_state != TCP_LISTEN &&
1501                     sk->sk_state != TCP_CLOSE)
1502                         goto out_dtefac_release;
1503                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1504                         goto out_dtefac_release;
1505                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1506                         goto out_dtefac_release;
1507                 x25->dte_facilities = dtefacs;
1508                 rc = 0;
1509 out_dtefac_release:
1510                 release_sock(sk);
1511                 break;
1512         }
1513
1514         case SIOCX25GCALLUSERDATA: {
1515                 lock_sock(sk);
1516                 rc = copy_to_user(argp, &x25->calluserdata,
1517                                   sizeof(x25->calluserdata))
1518                         ? -EFAULT : 0;
1519                 release_sock(sk);
1520                 break;
1521         }
1522
1523         case SIOCX25SCALLUSERDATA: {
1524                 struct x25_calluserdata calluserdata;
1525
1526                 rc = -EFAULT;
1527                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1528                         break;
1529                 rc = -EINVAL;
1530                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1531                         break;
1532                 lock_sock(sk);
1533                 x25->calluserdata = calluserdata;
1534                 release_sock(sk);
1535                 rc = 0;
1536                 break;
1537         }
1538
1539         case SIOCX25GCAUSEDIAG: {
1540                 lock_sock(sk);
1541                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1542                         ? -EFAULT : 0;
1543                 release_sock(sk);
1544                 break;
1545         }
1546
1547         case SIOCX25SCAUSEDIAG: {
1548                 struct x25_causediag causediag;
1549                 rc = -EFAULT;
1550                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1551                         break;
1552                 lock_sock(sk);
1553                 x25->causediag = causediag;
1554                 release_sock(sk);
1555                 rc = 0;
1556                 break;
1557
1558         }
1559
1560         case SIOCX25SCUDMATCHLEN: {
1561                 struct x25_subaddr sub_addr;
1562                 rc = -EINVAL;
1563                 lock_sock(sk);
1564                 if(sk->sk_state != TCP_CLOSE)
1565                         goto out_cud_release;
1566                 rc = -EFAULT;
1567                 if (copy_from_user(&sub_addr, argp,
1568                                    sizeof(sub_addr)))
1569                         goto out_cud_release;
1570                 rc = -EINVAL;
1571                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1572                         goto out_cud_release;
1573                 x25->cudmatchlength = sub_addr.cudmatchlength;
1574                 rc = 0;
1575 out_cud_release:
1576                 release_sock(sk);
1577                 break;
1578         }
1579
1580         case SIOCX25CALLACCPTAPPRV: {
1581                 rc = -EINVAL;
1582                 lock_sock(sk);
1583                 if (sk->sk_state == TCP_CLOSE) {
1584                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1585                         rc = 0;
1586                 }
1587                 release_sock(sk);
1588                 break;
1589         }
1590
1591         case SIOCX25SENDCALLACCPT:  {
1592                 rc = -EINVAL;
1593                 lock_sock(sk);
1594                 if (sk->sk_state != TCP_ESTABLISHED)
1595                         goto out_sendcallaccpt_release;
1596                 /* must call accptapprv above */
1597                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1598                         goto out_sendcallaccpt_release;
1599                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1600                 x25->state = X25_STATE_3;
1601                 rc = 0;
1602 out_sendcallaccpt_release:
1603                 release_sock(sk);
1604                 break;
1605         }
1606
1607         default:
1608                 rc = -ENOIOCTLCMD;
1609                 break;
1610         }
1611
1612         return rc;
1613 }
1614
1615 static const struct net_proto_family x25_family_ops = {
1616         .family =       AF_X25,
1617         .create =       x25_create,
1618         .owner  =       THIS_MODULE,
1619 };
1620
1621 #ifdef CONFIG_COMPAT
1622 static int compat_x25_subscr_ioctl(unsigned int cmd,
1623                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1624 {
1625         struct compat_x25_subscrip_struct x25_subscr;
1626         struct x25_neigh *nb;
1627         struct net_device *dev;
1628         int rc = -EINVAL;
1629
1630         rc = -EFAULT;
1631         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1632                 goto out;
1633
1634         rc = -EINVAL;
1635         dev = x25_dev_get(x25_subscr.device);
1636         if (dev == NULL)
1637                 goto out;
1638
1639         nb = x25_get_neigh(dev);
1640         if (nb == NULL)
1641                 goto out_dev_put;
1642
1643         dev_put(dev);
1644
1645         if (cmd == SIOCX25GSUBSCRIP) {
1646                 read_lock_bh(&x25_neigh_list_lock);
1647                 x25_subscr.extended = nb->extended;
1648                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1649                 read_unlock_bh(&x25_neigh_list_lock);
1650                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1651                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1652         } else {
1653                 rc = -EINVAL;
1654                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1655                         rc = 0;
1656                         write_lock_bh(&x25_neigh_list_lock);
1657                         nb->extended = x25_subscr.extended;
1658                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1659                         write_unlock_bh(&x25_neigh_list_lock);
1660                 }
1661         }
1662         x25_neigh_put(nb);
1663 out:
1664         return rc;
1665 out_dev_put:
1666         dev_put(dev);
1667         goto out;
1668 }
1669
1670 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1671                                 unsigned long arg)
1672 {
1673         void __user *argp = compat_ptr(arg);
1674         int rc = -ENOIOCTLCMD;
1675
1676         switch(cmd) {
1677         case TIOCOUTQ:
1678         case TIOCINQ:
1679                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1680                 break;
1681         case SIOCGIFADDR:
1682         case SIOCSIFADDR:
1683         case SIOCGIFDSTADDR:
1684         case SIOCSIFDSTADDR:
1685         case SIOCGIFBRDADDR:
1686         case SIOCSIFBRDADDR:
1687         case SIOCGIFNETMASK:
1688         case SIOCSIFNETMASK:
1689         case SIOCGIFMETRIC:
1690         case SIOCSIFMETRIC:
1691                 rc = -EINVAL;
1692                 break;
1693         case SIOCADDRT:
1694         case SIOCDELRT:
1695                 rc = -EPERM;
1696                 if (!capable(CAP_NET_ADMIN))
1697                         break;
1698                 rc = x25_route_ioctl(cmd, argp);
1699                 break;
1700         case SIOCX25GSUBSCRIP:
1701                 rc = compat_x25_subscr_ioctl(cmd, argp);
1702                 break;
1703         case SIOCX25SSUBSCRIP:
1704                 rc = -EPERM;
1705                 if (!capable(CAP_NET_ADMIN))
1706                         break;
1707                 rc = compat_x25_subscr_ioctl(cmd, argp);
1708                 break;
1709         case SIOCX25GFACILITIES:
1710         case SIOCX25SFACILITIES:
1711         case SIOCX25GDTEFACILITIES:
1712         case SIOCX25SDTEFACILITIES:
1713         case SIOCX25GCALLUSERDATA:
1714         case SIOCX25SCALLUSERDATA:
1715         case SIOCX25GCAUSEDIAG:
1716         case SIOCX25SCAUSEDIAG:
1717         case SIOCX25SCUDMATCHLEN:
1718         case SIOCX25CALLACCPTAPPRV:
1719         case SIOCX25SENDCALLACCPT:
1720                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1721                 break;
1722         default:
1723                 rc = -ENOIOCTLCMD;
1724                 break;
1725         }
1726         return rc;
1727 }
1728 #endif
1729
1730 static const struct proto_ops x25_proto_ops = {
1731         .family =       AF_X25,
1732         .owner =        THIS_MODULE,
1733         .release =      x25_release,
1734         .bind =         x25_bind,
1735         .connect =      x25_connect,
1736         .socketpair =   sock_no_socketpair,
1737         .accept =       x25_accept,
1738         .getname =      x25_getname,
1739         .poll =         datagram_poll,
1740         .ioctl =        x25_ioctl,
1741 #ifdef CONFIG_COMPAT
1742         .compat_ioctl = compat_x25_ioctl,
1743 #endif
1744         .gettstamp =    sock_gettstamp,
1745         .listen =       x25_listen,
1746         .shutdown =     sock_no_shutdown,
1747         .setsockopt =   x25_setsockopt,
1748         .getsockopt =   x25_getsockopt,
1749         .sendmsg =      x25_sendmsg,
1750         .recvmsg =      x25_recvmsg,
1751         .mmap =         sock_no_mmap,
1752         .sendpage =     sock_no_sendpage,
1753 };
1754
1755 static struct packet_type x25_packet_type __read_mostly = {
1756         .type = cpu_to_be16(ETH_P_X25),
1757         .func = x25_lapb_receive_frame,
1758 };
1759
1760 static struct notifier_block x25_dev_notifier = {
1761         .notifier_call = x25_device_event,
1762 };
1763
1764 void x25_kill_by_neigh(struct x25_neigh *nb)
1765 {
1766         struct sock *s;
1767
1768         write_lock_bh(&x25_list_lock);
1769
1770         sk_for_each(s, &x25_list) {
1771                 if (x25_sk(s)->neighbour == nb) {
1772                         write_unlock_bh(&x25_list_lock);
1773                         lock_sock(s);
1774                         x25_disconnect(s, ENETUNREACH, 0, 0);
1775                         release_sock(s);
1776                         write_lock_bh(&x25_list_lock);
1777                 }
1778         }
1779         write_unlock_bh(&x25_list_lock);
1780
1781         /* Remove any related forwards */
1782         x25_clear_forward_by_dev(nb->dev);
1783 }
1784
1785 static int __init x25_init(void)
1786 {
1787         int rc;
1788
1789         rc = proto_register(&x25_proto, 0);
1790         if (rc)
1791                 goto out;
1792
1793         rc = sock_register(&x25_family_ops);
1794         if (rc)
1795                 goto out_proto;
1796
1797         dev_add_pack(&x25_packet_type);
1798
1799         rc = register_netdevice_notifier(&x25_dev_notifier);
1800         if (rc)
1801                 goto out_sock;
1802
1803         rc = x25_register_sysctl();
1804         if (rc)
1805                 goto out_dev;
1806
1807         rc = x25_proc_init();
1808         if (rc)
1809                 goto out_sysctl;
1810
1811         pr_info("Linux Version 0.2\n");
1812
1813 out:
1814         return rc;
1815 out_sysctl:
1816         x25_unregister_sysctl();
1817 out_dev:
1818         unregister_netdevice_notifier(&x25_dev_notifier);
1819 out_sock:
1820         dev_remove_pack(&x25_packet_type);
1821         sock_unregister(AF_X25);
1822 out_proto:
1823         proto_unregister(&x25_proto);
1824         goto out;
1825 }
1826 module_init(x25_init);
1827
1828 static void __exit x25_exit(void)
1829 {
1830         x25_proc_exit();
1831         x25_link_free();
1832         x25_route_free();
1833
1834         x25_unregister_sysctl();
1835
1836         unregister_netdevice_notifier(&x25_dev_notifier);
1837
1838         dev_remove_pack(&x25_packet_type);
1839
1840         sock_unregister(AF_X25);
1841         proto_unregister(&x25_proto);
1842 }
1843 module_exit(x25_exit);
1844
1845 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1846 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1847 MODULE_LICENSE("GPL");
1848 MODULE_ALIAS_NETPROTO(PF_X25);