net/x25/af_x25.c

   1 /*
   2  *      X.25 Packet Layer release 002
   3  *
   4  *      This is ALPHA test software. This code may break your machine,
   5  *      randomly fail to work with new releases, misbehave and/or generally
   6  *      screw up. It might even work.
   7  *
   8  *      This code REQUIRES 2.1.15 or higher
   9  *
  10  *      This module:
  11  *              This module is free software; you can redistribute it and/or
  12  *              modify it under the terms of the GNU General Public License
  13  *              as published by the Free Software Foundation; either version
  14  *              2 of the License, or (at your option) any later version.
  15  *
  16  *      History
  17  *      X.25 001        Jonathan Naylor Started coding.
  18  *      X.25 002        Jonathan Naylor Centralised disconnect handling.
  19  *                                      New timer architecture.
  20  *      2000-03-11      Henner Eisen    MSG_EOR handling more POSIX compliant.
  21  *      2000-03-22      Daniela Squassoni Allowed disabling/enabling of
  22  *                                        facilities negotiation and increased
  23  *                                        the throughput upper limit.
  24  *      2000-08-27      Arnaldo C. Melo s/suser/capable/ + micro cleanups
  25  *      2000-09-04      Henner Eisen    Set sock->state in x25_accept().
  26  *                                      Fixed x25_output() related skb leakage.
  27  *      2000-10-02      Henner Eisen    Made x25_kick() single threaded per socket.
  28  *      2000-10-27      Henner Eisen    MSG_DONTWAIT for fragment allocation.
  29  *      2000-11-14      Henner Eisen    Closing datalink from NETDEV_GOING_DOWN
  30  *      2002-10-06      Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
  31  *                                      x25_proc.c, using seq_file
  32  *      2005-04-02      Shaun Pereira   Selective sub address matching
  33  *                                      with call user data
  34  *      2005-04-15      Shaun Pereira   Fast select with no restriction on
  35  *                                      response
  36  */
  37
  38 #define pr_fmt(fmt) "X25: " fmt
  39
  40 #include <linux/module.h>
  41 #include <linux/capability.h>
  42 #include <linux/errno.h>
  43 #include <linux/kernel.h>
  44 #include <linux/sched/signal.h>
  45 #include <linux/timer.h>
  46 #include <linux/string.h>
  47 #include <linux/net.h>
  48 #include <linux/netdevice.h>
  49 #include <linux/if_arp.h>
  50 #include <linux/skbuff.h>
  51 #include <linux/slab.h>
  52 #include <net/sock.h>
  53 #include <net/tcp_states.h>
  54 #include <linux/uaccess.h>
  55 #include <linux/fcntl.h>
  56 #include <linux/termios.h>      /* For TIOCINQ/OUTQ */
  57 #include <linux/notifier.h>
  58 #include <linux/init.h>
  59 #include <linux/compat.h>
  60 #include <linux/ctype.h>
  61
  62 #include <net/x25.h>
  63 #include <net/compat.h>
  64
  65 int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
  66 int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
  67 int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
  68 int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
  69 int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
  70 int sysctl_x25_forward                 = 0;
  71
  72 HLIST_HEAD(x25_list);
  73 DEFINE_RWLOCK(x25_list_lock);
  74
  75 static const struct proto_ops x25_proto_ops;
  76
  77 static const struct x25_address null_x25_address = {"               "};
  78
  79 #ifdef CONFIG_COMPAT
  80 struct compat_x25_subscrip_struct {
  81         char device[200-sizeof(compat_ulong_t)];
  82         compat_ulong_t global_facil_mask;
  83         compat_uint_t extended;
  84 };
  85 #endif
  86
  87
  88 int x25_parse_address_block(struct sk_buff *skb,
  89                 struct x25_address *called_addr,
  90                 struct x25_address *calling_addr)
  91 {
  92         unsigned char len;
  93         int needed;
  94         int rc;
  95
  96         if (!pskb_may_pull(skb, 1)) {
  97                 /* packet has no address block */
  98                 rc = 0;
  99                 goto empty;
 100         }
 101
 102         len = *skb->data;
 103         needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2;
 104
 105         if (!pskb_may_pull(skb, needed)) {
 106                 /* packet is too short to hold the addresses it claims
 107                    to hold */
 108                 rc = -1;
 109                 goto empty;
 110         }
 111
 112         return x25_addr_ntoa(skb->data, called_addr, calling_addr);
 113
 114 empty:
 115         *called_addr->x25_addr = 0;
 116         *calling_addr->x25_addr = 0;
 117
 118         return rc;
 119 }
 120
 121
 122 int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
 123                   struct x25_address *calling_addr)
 124 {
 125         unsigned int called_len, calling_len;
 126         char *called, *calling;
 127         unsigned int i;
 128
 129         called_len  = (*p >> 0) & 0x0F;
 130         calling_len = (*p >> 4) & 0x0F;
 131
 132         called  = called_addr->x25_addr;
 133         calling = calling_addr->x25_addr;
 134         p++;
 135
 136         for (i = 0; i < (called_len + calling_len); i++) {
 137                 if (i < called_len) {
 138                         if (i % 2 != 0) {
 139                                 *called++ = ((*p >> 0) & 0x0F) + '0';
 140                                 p++;
 141                         } else {
 142                                 *called++ = ((*p >> 4) & 0x0F) + '0';
 143                         }
 144                 } else {
 145                         if (i % 2 != 0) {
 146                                 *calling++ = ((*p >> 0) & 0x0F) + '0';
 147                                 p++;
 148                         } else {
 149                                 *calling++ = ((*p >> 4) & 0x0F) + '0';
 150                         }
 151                 }
 152         }
 153
 154         *called = *calling = '\0';
 155
 156         return 1 + (called_len + calling_len + 1) / 2;
 157 }
 158
 159 int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
 160                   struct x25_address *calling_addr)
 161 {
 162         unsigned int called_len, calling_len;
 163         char *called, *calling;
 164         int i;
 165
 166         called  = called_addr->x25_addr;
 167         calling = calling_addr->x25_addr;
 168
 169         called_len  = strlen(called);
 170         calling_len = strlen(calling);
 171
 172         *p++ = (calling_len << 4) | (called_len << 0);
 173
 174         for (i = 0; i < (called_len + calling_len); i++) {
 175                 if (i < called_len) {
 176                         if (i % 2 != 0) {
 177                                 *p |= (*called++ - '0') << 0;
 178                                 p++;
 179                         } else {
 180                                 *p = 0x00;
 181                                 *p |= (*called++ - '0') << 4;
 182                         }
 183                 } else {
 184                         if (i % 2 != 0) {
 185                                 *p |= (*calling++ - '0') << 0;
 186                                 p++;
 187                         } else {
 188                                 *p = 0x00;
 189                                 *p |= (*calling++ - '0') << 4;
 190                         }
 191                 }
 192         }
 193
 194         return 1 + (called_len + calling_len + 1) / 2;
 195 }
 196
 197 /*
 198  *      Socket removal during an interrupt is now safe.
 199  */
 200 static void x25_remove_socket(struct sock *sk)
 201 {
 202         write_lock_bh(&x25_list_lock);
 203         sk_del_node_init(sk);
 204         write_unlock_bh(&x25_list_lock);
 205 }
 206
 207 /*
 208  *      Kill all bound sockets on a dropped device.
 209  */
 210 static void x25_kill_by_device(struct net_device *dev)
 211 {
 212         struct sock *s;
 213
 214         write_lock_bh(&x25_list_lock);
 215
 216         sk_for_each(s, &x25_list)
 217                 if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
 218                         x25_disconnect(s, ENETUNREACH, 0, 0);
 219
 220         write_unlock_bh(&x25_list_lock);
 221 }
 222
 223 /*
 224  *      Handle device status changes.
 225  */
 226 static int x25_device_event(struct notifier_block *this, unsigned long event,
 227                             void *ptr)
 228 {
 229         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 230         struct x25_neigh *nb;
 231
 232         if (!net_eq(dev_net(dev), &init_net))
 233                 return NOTIFY_DONE;
 234
 235         if (dev->type == ARPHRD_X25
 236 #if IS_ENABLED(CONFIG_LLC)
 237          || dev->type == ARPHRD_ETHER
 238 #endif
 239          ) {
 240                 switch (event) {
 241                 case NETDEV_UP:
 242                         x25_link_device_up(dev);
 243                         break;
 244                 case NETDEV_GOING_DOWN:
 245                         nb = x25_get_neigh(dev);
 246                         if (nb) {
 247                                 x25_terminate_link(nb);
 248                                 x25_neigh_put(nb);
 249                         }
 250                         break;
 251                 case NETDEV_DOWN:
 252                         x25_kill_by_device(dev);
 253                         x25_route_device_down(dev);
 254                         x25_link_device_down(dev);
 255                         break;
 256                 }
 257         }
 258
 259         return NOTIFY_DONE;
 260 }
 261
 262 /*
 263  *      Add a socket to the bound sockets list.
 264  */
 265 static void x25_insert_socket(struct sock *sk)
 266 {
 267         write_lock_bh(&x25_list_lock);
 268         sk_add_node(sk, &x25_list);
 269         write_unlock_bh(&x25_list_lock);
 270 }
 271
 272 /*
 273  *      Find a socket that wants to accept the Call Request we just
 274  *      received. Check the full list for an address/cud match.
 275  *      If no cuds match return the next_best thing, an address match.
 276  *      Note: if a listening socket has cud set it must only get calls
 277  *      with matching cud.
 278  */
 279 static struct sock *x25_find_listener(struct x25_address *addr,
 280                                         struct sk_buff *skb)
 281 {
 282         struct sock *s;
 283         struct sock *next_best;
 284
 285         read_lock_bh(&x25_list_lock);
 286         next_best = NULL;
 287
 288         sk_for_each(s, &x25_list)
 289                 if ((!strcmp(addr->x25_addr,
 290                         x25_sk(s)->source_addr.x25_addr) ||
 291                                 !strcmp(x25_sk(s)->source_addr.x25_addr,
 292                                         null_x25_address.x25_addr)) &&
 293                                         s->sk_state == TCP_LISTEN) {
 294                         /*
 295                          * Found a listening socket, now check the incoming
 296                          * call user data vs this sockets call user data
 297                          */
 298                         if (x25_sk(s)->cudmatchlength > 0 &&
 299                                 skb->len >= x25_sk(s)->cudmatchlength) {
 300                                 if((memcmp(x25_sk(s)->calluserdata.cuddata,
 301                                         skb->data,
 302                                         x25_sk(s)->cudmatchlength)) == 0) {
 303                                         sock_hold(s);
 304                                         goto found;
 305                                  }
 306                         } else
 307                                 next_best = s;
 308                 }
 309         if (next_best) {
 310                 s = next_best;
 311                 sock_hold(s);
 312                 goto found;
 313         }
 314         s = NULL;
 315 found:
 316         read_unlock_bh(&x25_list_lock);
 317         return s;
 318 }
 319
 320 /*
 321  *      Find a connected X.25 socket given my LCI and neighbour.
 322  */
 323 static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 324 {
 325         struct sock *s;
 326
 327         sk_for_each(s, &x25_list)
 328                 if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
 329                         sock_hold(s);
 330                         goto found;
 331                 }
 332         s = NULL;
 333 found:
 334         return s;
 335 }
 336
 337 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 338 {
 339         struct sock *s;
 340
 341         read_lock_bh(&x25_list_lock);
 342         s = __x25_find_socket(lci, nb);
 343         read_unlock_bh(&x25_list_lock);
 344         return s;
 345 }
 346
 347 /*
 348  *      Find a unique LCI for a given device.
 349  */
 350 static unsigned int x25_new_lci(struct x25_neigh *nb)
 351 {
 352         unsigned int lci = 1;
 353         struct sock *sk;
 354
 355         while ((sk = x25_find_socket(lci, nb)) != NULL) {
 356                 sock_put(sk);
 357                 if (++lci == 4096) {
 358                         lci = 0;
 359                         break;
 360                 }
 361                 cond_resched();
 362         }
 363
 364         return lci;
 365 }
 366
 367 /*
 368  *      Deferred destroy.
 369  */
 370 static void __x25_destroy_socket(struct sock *);
 371
 372 /*
 373  *      handler for deferred kills.
 374  */
 375 static void x25_destroy_timer(struct timer_list *t)
 376 {
 377         struct sock *sk = from_timer(sk, t, sk_timer);
 378
 379         x25_destroy_socket_from_timer(sk);
 380 }
 381
 382 /*
 383  *      This is called from user mode and the timers. Thus it protects itself
 384  *      against interrupt users but doesn't worry about being called during
 385  *      work. Once it is removed from the queue no interrupt or bottom half
 386  *      will touch it and we are (fairly 8-) ) safe.
 387  *      Not static as it's used by the timer
 388  */
 389 static void __x25_destroy_socket(struct sock *sk)
 390 {
 391         struct sk_buff *skb;
 392
 393         x25_stop_heartbeat(sk);
 394         x25_stop_timer(sk);
 395
 396         x25_remove_socket(sk);
 397         x25_clear_queues(sk);           /* Flush the queues */
 398
 399         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 400                 if (skb->sk != sk) {            /* A pending connection */
 401                         /*
 402                          * Queue the unaccepted socket for death
 403                          */
 404                         skb->sk->sk_state = TCP_LISTEN;
 405                         sock_set_flag(skb->sk, SOCK_DEAD);
 406                         x25_start_heartbeat(skb->sk);
 407                         x25_sk(skb->sk)->state = X25_STATE_0;
 408                 }
 409
 410                 kfree_skb(skb);
 411         }
 412
 413         if (sk_has_allocations(sk)) {
 414                 /* Defer: outstanding buffers */
 415                 sk->sk_timer.expires  = jiffies + 10 * HZ;
 416                 sk->sk_timer.function = x25_destroy_timer;
 417                 add_timer(&sk->sk_timer);
 418         } else {
 419                 /* drop last reference so sock_put will free */
 420                 __sock_put(sk);
 421         }
 422 }
 423
 424 void x25_destroy_socket_from_timer(struct sock *sk)
 425 {
 426         sock_hold(sk);
 427         bh_lock_sock(sk);
 428         __x25_destroy_socket(sk);
 429         bh_unlock_sock(sk);
 430         sock_put(sk);
 431 }
 432
 433 /*
 434  *      Handling for system calls applied via the various interfaces to a
 435  *      X.25 socket object.
 436  */
 437
 438 static int x25_setsockopt(struct socket *sock, int level, int optname,
 439                           char __user *optval, unsigned int optlen)
 440 {
 441         int opt;
 442         struct sock *sk = sock->sk;
 443         int rc = -ENOPROTOOPT;
 444
 445         if (level != SOL_X25 || optname != X25_QBITINCL)
 446                 goto out;
 447
 448         rc = -EINVAL;
 449         if (optlen < sizeof(int))
 450                 goto out;
 451
 452         rc = -EFAULT;
 453         if (get_user(opt, (int __user *)optval))
 454                 goto out;
 455
 456         if (opt)
 457                 set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 458         else
 459                 clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 460         rc = 0;
 461 out:
 462         return rc;
 463 }
 464
 465 static int x25_getsockopt(struct socket *sock, int level, int optname,
 466                           char __user *optval, int __user *optlen)
 467 {
 468         struct sock *sk = sock->sk;
 469         int val, len, rc = -ENOPROTOOPT;
 470
 471         if (level != SOL_X25 || optname != X25_QBITINCL)
 472                 goto out;
 473
 474         rc = -EFAULT;
 475         if (get_user(len, optlen))
 476                 goto out;
 477
 478         len = min_t(unsigned int, len, sizeof(int));
 479
 480         rc = -EINVAL;
 481         if (len < 0)
 482                 goto out;
 483
 484         rc = -EFAULT;
 485         if (put_user(len, optlen))
 486                 goto out;
 487
 488         val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 489         rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
 490 out:
 491         return rc;
 492 }
 493
 494 static int x25_listen(struct socket *sock, int backlog)
 495 {
 496         struct sock *sk = sock->sk;
 497         int rc = -EOPNOTSUPP;
 498
 499         lock_sock(sk);
 500         if (sock->state != SS_UNCONNECTED) {
 501                 rc = -EINVAL;
 502                 release_sock(sk);
 503                 return rc;
 504         }
 505
 506         if (sk->sk_state != TCP_LISTEN) {
 507                 memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 508                 sk->sk_max_ack_backlog = backlog;
 509                 sk->sk_state           = TCP_LISTEN;
 510                 rc = 0;
 511         }
 512         release_sock(sk);
 513
 514         return rc;
 515 }
 516
 517 static struct proto x25_proto = {
 518         .name     = "X25",
 519         .owner    = THIS_MODULE,
 520         .obj_size = sizeof(struct x25_sock),
 521 };
 522
 523 static struct sock *x25_alloc_socket(struct net *net, int kern)
 524 {
 525         struct x25_sock *x25;
 526         struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 527
 528         if (!sk)
 529                 goto out;
 530
 531         sock_init_data(NULL, sk);
 532
 533         x25 = x25_sk(sk);
 534         skb_queue_head_init(&x25->ack_queue);
 535         skb_queue_head_init(&x25->fragment_queue);
 536         skb_queue_head_init(&x25->interrupt_in_queue);
 537         skb_queue_head_init(&x25->interrupt_out_queue);
 538 out:
 539         return sk;
 540 }
 541
 542 static int x25_create(struct net *net, struct socket *sock, int protocol,
 543                       int kern)
 544 {
 545         struct sock *sk;
 546         struct x25_sock *x25;
 547         int rc = -EAFNOSUPPORT;
 548
 549         if (!net_eq(net, &init_net))
 550                 goto out;
 551
 552         rc = -ESOCKTNOSUPPORT;
 553         if (sock->type != SOCK_SEQPACKET)
 554                 goto out;
 555
 556         rc = -EINVAL;
 557         if (protocol)
 558                 goto out;
 559
 560         rc = -ENOMEM;
 561         if ((sk = x25_alloc_socket(net, kern)) == NULL)
 562                 goto out;
 563
 564         x25 = x25_sk(sk);
 565
 566         sock_init_data(sock, sk);
 567
 568         x25_init_timers(sk);
 569
 570         sock->ops    = &x25_proto_ops;
 571         sk->sk_protocol = protocol;
 572         sk->sk_backlog_rcv = x25_backlog_rcv;
 573
 574         x25->t21   = sysctl_x25_call_request_timeout;
 575         x25->t22   = sysctl_x25_reset_request_timeout;
 576         x25->t23   = sysctl_x25_clear_request_timeout;
 577         x25->t2    = sysctl_x25_ack_holdback_timeout;
 578         x25->state = X25_STATE_0;
 579         x25->cudmatchlength = 0;
 580         set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);     /* normally no cud  */
 581                                                         /* on call accept   */
 582
 583         x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 584         x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 585         x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 586         x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 587         x25->facilities.throughput  = 0;        /* by default don't negotiate
 588                                                    throughput */
 589         x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 590         x25->dte_facilities.calling_len = 0;
 591         x25->dte_facilities.called_len = 0;
 592         memset(x25->dte_facilities.called_ae, '\0',
 593                         sizeof(x25->dte_facilities.called_ae));
 594         memset(x25->dte_facilities.calling_ae, '\0',
 595                         sizeof(x25->dte_facilities.calling_ae));
 596
 597         rc = 0;
 598 out:
 599         return rc;
 600 }
 601
 602 static struct sock *x25_make_new(struct sock *osk)
 603 {
 604         struct sock *sk = NULL;
 605         struct x25_sock *x25, *ox25;
 606
 607         if (osk->sk_type != SOCK_SEQPACKET)
 608                 goto out;
 609
 610         if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 611                 goto out;
 612
 613         x25 = x25_sk(sk);
 614
 615         sk->sk_type        = osk->sk_type;
 616         sk->sk_priority    = osk->sk_priority;
 617         sk->sk_protocol    = osk->sk_protocol;
 618         sk->sk_rcvbuf      = osk->sk_rcvbuf;
 619         sk->sk_sndbuf      = osk->sk_sndbuf;
 620         sk->sk_state       = TCP_ESTABLISHED;
 621         sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 622         sock_copy_flags(sk, osk);
 623
 624         ox25 = x25_sk(osk);
 625         x25->t21        = ox25->t21;
 626         x25->t22        = ox25->t22;
 627         x25->t23        = ox25->t23;
 628         x25->t2         = ox25->t2;
 629         x25->flags      = ox25->flags;
 630         x25->facilities = ox25->facilities;
 631         x25->dte_facilities = ox25->dte_facilities;
 632         x25->cudmatchlength = ox25->cudmatchlength;
 633
 634         clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 635         x25_init_timers(sk);
 636 out:
 637         return sk;
 638 }
 639
 640 static int x25_release(struct socket *sock)
 641 {
 642         struct sock *sk = sock->sk;
 643         struct x25_sock *x25;
 644
 645         if (!sk)
 646                 return 0;
 647
 648         x25 = x25_sk(sk);
 649
 650         sock_hold(sk);
 651         lock_sock(sk);
 652         switch (x25->state) {
 653
 654                 case X25_STATE_0:
 655                 case X25_STATE_2:
 656                         x25_disconnect(sk, 0, 0, 0);
 657                         __x25_destroy_socket(sk);
 658                         goto out;
 659
 660                 case X25_STATE_1:
 661                 case X25_STATE_3:
 662                 case X25_STATE_4:
 663                         x25_clear_queues(sk);
 664                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 665                         x25_start_t23timer(sk);
 666                         x25->state = X25_STATE_2;
 667                         sk->sk_state    = TCP_CLOSE;
 668                         sk->sk_shutdown |= SEND_SHUTDOWN;
 669                         sk->sk_state_change(sk);
 670                         sock_set_flag(sk, SOCK_DEAD);
 671                         sock_set_flag(sk, SOCK_DESTROY);
 672                         break;
 673         }
 674
 675         sock_orphan(sk);
 676 out:
 677         release_sock(sk);
 678         sock_put(sk);
 679         return 0;
 680 }
 681
 682 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 683 {
 684         struct sock *sk = sock->sk;
 685         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 686         int len, i, rc = 0;
 687
 688         if (addr_len != sizeof(struct sockaddr_x25) ||
 689             addr->sx25_family != AF_X25 ||
 690             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) {
 691                 rc = -EINVAL;
 692                 goto out;
 693         }
 694
 695         /* check for the null_x25_address */
 696         if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
 697
 698                 len = strlen(addr->sx25_addr.x25_addr);
 699                 for (i = 0; i < len; i++) {
 700                         if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 701                                 rc = -EINVAL;
 702                                 goto out;
 703                         }
 704                 }
 705         }
 706
 707         lock_sock(sk);
 708         if (sock_flag(sk, SOCK_ZAPPED)) {
 709                 x25_sk(sk)->source_addr = addr->sx25_addr;
 710                 x25_insert_socket(sk);
 711                 sock_reset_flag(sk, SOCK_ZAPPED);
 712         } else {
 713                 rc = -EINVAL;
 714         }
 715         release_sock(sk);
 716         SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
 717 out:
 718         return rc;
 719 }
 720
 721 static int x25_wait_for_connection_establishment(struct sock *sk)
 722 {
 723         DECLARE_WAITQUEUE(wait, current);
 724         int rc;
 725
 726         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 727         for (;;) {
 728                 __set_current_state(TASK_INTERRUPTIBLE);
 729                 rc = -ERESTARTSYS;
 730                 if (signal_pending(current))
 731                         break;
 732                 rc = sock_error(sk);
 733                 if (rc) {
 734                         sk->sk_socket->state = SS_UNCONNECTED;
 735                         break;
 736                 }
 737                 rc = 0;
 738                 if (sk->sk_state != TCP_ESTABLISHED) {
 739                         release_sock(sk);
 740                         schedule();
 741                         lock_sock(sk);
 742                 } else
 743                         break;
 744         }
 745         __set_current_state(TASK_RUNNING);
 746         remove_wait_queue(sk_sleep(sk), &wait);
 747         return rc;
 748 }
 749
 750 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
 751                        int addr_len, int flags)
 752 {
 753         struct sock *sk = sock->sk;
 754         struct x25_sock *x25 = x25_sk(sk);
 755         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 756         struct x25_route *rt;
 757         int rc = 0;
 758
 759         lock_sock(sk);
 760         if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 761                 sock->state = SS_CONNECTED;
 762                 goto out; /* Connect completed during a ERESTARTSYS event */
 763         }
 764
 765         rc = -ECONNREFUSED;
 766         if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 767                 sock->state = SS_UNCONNECTED;
 768                 goto out;
 769         }
 770
 771         rc = -EISCONN;  /* No reconnect on a seqpacket socket */
 772         if (sk->sk_state == TCP_ESTABLISHED)
 773                 goto out;
 774
 775         rc = -EALREADY; /* Do nothing if call is already in progress */
 776         if (sk->sk_state == TCP_SYN_SENT)
 777                 goto out;
 778
 779         sk->sk_state   = TCP_CLOSE;
 780         sock->state = SS_UNCONNECTED;
 781
 782         rc = -EINVAL;
 783         if (addr_len != sizeof(struct sockaddr_x25) ||
 784             addr->sx25_family != AF_X25 ||
 785             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN)
 786                 goto out;
 787
 788         rc = -ENETUNREACH;
 789         rt = x25_get_route(&addr->sx25_addr);
 790         if (!rt)
 791                 goto out;
 792
 793         x25->neighbour = x25_get_neigh(rt->dev);
 794         if (!x25->neighbour)
 795                 goto out_put_route;
 796
 797         x25_limit_facilities(&x25->facilities, x25->neighbour);
 798
 799         x25->lci = x25_new_lci(x25->neighbour);
 800         if (!x25->lci)
 801                 goto out_put_neigh;
 802
 803         rc = -EINVAL;
 804         if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 805                 goto out_put_neigh;
 806
 807         if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 808                 memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 809
 810         x25->dest_addr = addr->sx25_addr;
 811
 812         /* Move to connecting socket, start sending Connect Requests */
 813         sock->state   = SS_CONNECTING;
 814         sk->sk_state  = TCP_SYN_SENT;
 815
 816         x25->state = X25_STATE_1;
 817
 818         x25_write_internal(sk, X25_CALL_REQUEST);
 819
 820         x25_start_heartbeat(sk);
 821         x25_start_t21timer(sk);
 822
 823         /* Now the loop */
 824         rc = -EINPROGRESS;
 825         if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 826                 goto out;
 827
 828         rc = x25_wait_for_connection_establishment(sk);
 829         if (rc)
 830                 goto out_put_neigh;
 831
 832         sock->state = SS_CONNECTED;
 833         rc = 0;
 834 out_put_neigh:
 835         if (rc && x25->neighbour) {
 836                 read_lock_bh(&x25_list_lock);
 837                 x25_neigh_put(x25->neighbour);
 838                 x25->neighbour = NULL;
 839                 read_unlock_bh(&x25_list_lock);
 840                 x25->state = X25_STATE_0;
 841         }
 842 out_put_route:
 843         x25_route_put(rt);
 844 out:
 845         release_sock(sk);
 846         return rc;
 847 }
 848
 849 static int x25_wait_for_data(struct sock *sk, long timeout)
 850 {
 851         DECLARE_WAITQUEUE(wait, current);
 852         int rc = 0;
 853
 854         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 855         for (;;) {
 856                 __set_current_state(TASK_INTERRUPTIBLE);
 857                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 858                         break;
 859                 rc = -ERESTARTSYS;
 860                 if (signal_pending(current))
 861                         break;
 862                 rc = -EAGAIN;
 863                 if (!timeout)
 864                         break;
 865                 rc = 0;
 866                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 867                         release_sock(sk);
 868                         timeout = schedule_timeout(timeout);
 869                         lock_sock(sk);
 870                 } else
 871                         break;
 872         }
 873         __set_current_state(TASK_RUNNING);
 874         remove_wait_queue(sk_sleep(sk), &wait);
 875         return rc;
 876 }
 877
 878 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 879                       bool kern)
 880 {
 881         struct sock *sk = sock->sk;
 882         struct sock *newsk;
 883         struct sk_buff *skb;
 884         int rc = -EINVAL;
 885
 886         if (!sk)
 887                 goto out;
 888
 889         rc = -EOPNOTSUPP;
 890         if (sk->sk_type != SOCK_SEQPACKET)
 891                 goto out;
 892
 893         lock_sock(sk);
 894         rc = -EINVAL;
 895         if (sk->sk_state != TCP_LISTEN)
 896                 goto out2;
 897
 898         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 899         if (rc)
 900                 goto out2;
 901         skb = skb_dequeue(&sk->sk_receive_queue);
 902         rc = -EINVAL;
 903         if (!skb->sk)
 904                 goto out2;
 905         newsk            = skb->sk;
 906         sock_graft(newsk, newsock);
 907
 908         /* Now attach up the new socket */
 909         skb->sk = NULL;
 910         kfree_skb(skb);
 911         sk->sk_ack_backlog--;
 912         newsock->state = SS_CONNECTED;
 913         rc = 0;
 914 out2:
 915         release_sock(sk);
 916 out:
 917         return rc;
 918 }
 919
 920 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 921                        int peer)
 922 {
 923         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 924         struct sock *sk = sock->sk;
 925         struct x25_sock *x25 = x25_sk(sk);
 926         int rc = 0;
 927
 928         if (peer) {
 929                 if (sk->sk_state != TCP_ESTABLISHED) {
 930                         rc = -ENOTCONN;
 931                         goto out;
 932                 }
 933                 sx25->sx25_addr = x25->dest_addr;
 934         } else
 935                 sx25->sx25_addr = x25->source_addr;
 936
 937         sx25->sx25_family = AF_X25;
 938         rc = sizeof(*sx25);
 939
 940 out:
 941         return rc;
 942 }
 943
 944 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 945                         unsigned int lci)
 946 {
 947         struct sock *sk;
 948         struct sock *make;
 949         struct x25_sock *makex25;
 950         struct x25_address source_addr, dest_addr;
 951         struct x25_facilities facilities;
 952         struct x25_dte_facilities dte_facilities;
 953         int len, addr_len, rc;
 954
 955         /*
 956          *      Remove the LCI and frame type.
 957          */
 958         skb_pull(skb, X25_STD_MIN_LEN);
 959
 960         /*
 961          *      Extract the X.25 addresses and convert them to ASCII strings,
 962          *      and remove them.
 963          *
 964          *      Address block is mandatory in call request packets
 965          */
 966         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 967         if (addr_len <= 0)
 968                 goto out_clear_request;
 969         skb_pull(skb, addr_len);
 970
 971         /*
 972          *      Get the length of the facilities, skip past them for the moment
 973          *      get the call user data because this is needed to determine
 974          *      the correct listener
 975          *
 976          *      Facilities length is mandatory in call request packets
 977          */
 978         if (!pskb_may_pull(skb, 1))
 979                 goto out_clear_request;
 980         len = skb->data[0] + 1;
 981         if (!pskb_may_pull(skb, len))
 982                 goto out_clear_request;
 983         skb_pull(skb,len);
 984
 985         /*
 986          *      Ensure that the amount of call user data is valid.
 987          */
 988         if (skb->len > X25_MAX_CUD_LEN)
 989                 goto out_clear_request;
 990
 991         /*
 992          *      Get all the call user data so it can be used in
 993          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 994          */
 995         if (!pskb_may_pull(skb, skb->len))
 996                 goto out_clear_request;
 997
 998         /*
 999          *      Find a listener for the particular address/cud pair.
1000          */
1001         sk = x25_find_listener(&source_addr,skb);
1002         skb_push(skb,len);
1003
1004         if (sk != NULL && sk_acceptq_is_full(sk)) {
1005                 goto out_sock_put;
1006         }
1007
1008         /*
1009          *      We dont have any listeners for this incoming call.
1010          *      Try forwarding it.
1011          */
1012         if (sk == NULL) {
1013                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
1014                 if (sysctl_x25_forward &&
1015                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1016                 {
1017                         /* Call was forwarded, dont process it any more */
1018                         kfree_skb(skb);
1019                         rc = 1;
1020                         goto out;
1021                 } else {
1022                         /* No listeners, can't forward, clear the call */
1023                         goto out_clear_request;
1024                 }
1025         }
1026
1027         /*
1028          *      Try to reach a compromise on the requested facilities.
1029          */
1030         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1031         if (len == -1)
1032                 goto out_sock_put;
1033
1034         /*
1035          * current neighbour/link might impose additional limits
1036          * on certain facilties
1037          */
1038
1039         x25_limit_facilities(&facilities, nb);
1040
1041         /*
1042          *      Try to create a new socket.
1043          */
1044         make = x25_make_new(sk);
1045         if (!make)
1046                 goto out_sock_put;
1047
1048         /*
1049          *      Remove the facilities
1050          */
1051         skb_pull(skb, len);
1052
1053         skb->sk     = make;
1054         make->sk_state = TCP_ESTABLISHED;
1055
1056         makex25 = x25_sk(make);
1057         makex25->lci           = lci;
1058         makex25->dest_addr     = dest_addr;
1059         makex25->source_addr   = source_addr;
1060         x25_neigh_hold(nb);
1061         makex25->neighbour     = nb;
1062         makex25->facilities    = facilities;
1063         makex25->dte_facilities= dte_facilities;
1064         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1065         /* ensure no reverse facil on accept */
1066         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1067         /* ensure no calling address extension on accept */
1068         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1069         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1070
1071         /* Normally all calls are accepted immediately */
1072         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1073                 x25_write_internal(make, X25_CALL_ACCEPTED);
1074                 makex25->state = X25_STATE_3;
1075         }
1076
1077         /*
1078          *      Incoming Call User Data.
1079          */
1080         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1081         makex25->calluserdata.cudlength = skb->len;
1082
1083         sk->sk_ack_backlog++;
1084
1085         x25_insert_socket(make);
1086
1087         skb_queue_head(&sk->sk_receive_queue, skb);
1088
1089         x25_start_heartbeat(make);
1090
1091         if (!sock_flag(sk, SOCK_DEAD))
1092                 sk->sk_data_ready(sk);
1093         rc = 1;
1094         sock_put(sk);
1095 out:
1096         return rc;
1097 out_sock_put:
1098         sock_put(sk);
1099 out_clear_request:
1100         rc = 0;
1101         x25_transmit_clear_request(nb, lci, 0x01);
1102         goto out;
1103 }
1104
1105 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1106 {
1107         struct sock *sk = sock->sk;
1108         struct x25_sock *x25 = x25_sk(sk);
1109         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1110         struct sockaddr_x25 sx25;
1111         struct sk_buff *skb;
1112         unsigned char *asmptr;
1113         int noblock = msg->msg_flags & MSG_DONTWAIT;
1114         size_t size;
1115         int qbit = 0, rc = -EINVAL;
1116
1117         lock_sock(sk);
1118         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1119                 goto out;
1120
1121         /* we currently don't support segmented records at the user interface */
1122         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1123                 goto out;
1124
1125         rc = -EADDRNOTAVAIL;
1126         if (sock_flag(sk, SOCK_ZAPPED))
1127                 goto out;
1128
1129         rc = -EPIPE;
1130         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1131                 send_sig(SIGPIPE, current, 0);
1132                 goto out;
1133         }
1134
1135         rc = -ENETUNREACH;
1136         if (!x25->neighbour)
1137                 goto out;
1138
1139         if (usx25) {
1140                 rc = -EINVAL;
1141                 if (msg->msg_namelen < sizeof(sx25))
1142                         goto out;
1143                 memcpy(&sx25, usx25, sizeof(sx25));
1144                 rc = -EISCONN;
1145                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1146                         goto out;
1147                 rc = -EINVAL;
1148                 if (sx25.sx25_family != AF_X25)
1149                         goto out;
1150         } else {
1151                 /*
1152                  *      FIXME 1003.1g - if the socket is like this because
1153                  *      it has become closed (not started closed) we ought
1154                  *      to SIGPIPE, EPIPE;
1155                  */
1156                 rc = -ENOTCONN;
1157                 if (sk->sk_state != TCP_ESTABLISHED)
1158                         goto out;
1159
1160                 sx25.sx25_family = AF_X25;
1161                 sx25.sx25_addr   = x25->dest_addr;
1162         }
1163
1164         /* Sanity check the packet size */
1165         if (len > 65535) {
1166                 rc = -EMSGSIZE;
1167                 goto out;
1168         }
1169
1170         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1171
1172         /* Build a packet */
1173         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1174
1175         if ((msg->msg_flags & MSG_OOB) && len > 32)
1176                 len = 32;
1177
1178         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1179
1180         release_sock(sk);
1181         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1182         lock_sock(sk);
1183         if (!skb)
1184                 goto out;
1185         X25_SKB_CB(skb)->flags = msg->msg_flags;
1186
1187         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1188
1189         /*
1190          *      Put the data on the end
1191          */
1192         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1193
1194         skb_reset_transport_header(skb);
1195         skb_put(skb, len);
1196
1197         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1198         if (rc)
1199                 goto out_kfree_skb;
1200
1201         /*
1202          *      If the Q BIT Include socket option is in force, the first
1203          *      byte of the user data is the logical value of the Q Bit.
1204          */
1205         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1206                 if (!pskb_may_pull(skb, 1))
1207                         goto out_kfree_skb;
1208
1209                 qbit = skb->data[0];
1210                 skb_pull(skb, 1);
1211         }
1212
1213         /*
1214          *      Push down the X.25 header
1215          */
1216         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1217
1218         if (msg->msg_flags & MSG_OOB) {
1219                 if (x25->neighbour->extended) {
1220                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1221                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1222                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1223                         *asmptr++ = X25_INTERRUPT;
1224                 } else {
1225                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1226                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1227                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1228                         *asmptr++ = X25_INTERRUPT;
1229                 }
1230         } else {
1231                 if (x25->neighbour->extended) {
1232                         /* Build an Extended X.25 header */
1233                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1234                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1235                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1236                         *asmptr++ = X25_DATA;
1237                         *asmptr++ = X25_DATA;
1238                 } else {
1239                         /* Build an Standard X.25 header */
1240                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1241                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1242                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1243                         *asmptr++ = X25_DATA;
1244                 }
1245
1246                 if (qbit)
1247                         skb->data[0] |= X25_Q_BIT;
1248         }
1249
1250         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1251         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1252
1253         rc = -ENOTCONN;
1254         if (sk->sk_state != TCP_ESTABLISHED)
1255                 goto out_kfree_skb;
1256
1257         if (msg->msg_flags & MSG_OOB)
1258                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1259         else {
1260                 rc = x25_output(sk, skb);
1261                 len = rc;
1262                 if (rc < 0)
1263                         kfree_skb(skb);
1264                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1265                         len++;
1266         }
1267
1268         x25_kick(sk);
1269         rc = len;
1270 out:
1271         release_sock(sk);
1272         return rc;
1273 out_kfree_skb:
1274         kfree_skb(skb);
1275         goto out;
1276 }
1277
1278
1279 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1280                        int flags)
1281 {
1282         struct sock *sk = sock->sk;
1283         struct x25_sock *x25 = x25_sk(sk);
1284         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1285         size_t copied;
1286         int qbit, header_len;
1287         struct sk_buff *skb;
1288         unsigned char *asmptr;
1289         int rc = -ENOTCONN;
1290
1291         lock_sock(sk);
1292
1293         if (x25->neighbour == NULL)
1294                 goto out;
1295
1296         header_len = x25->neighbour->extended ?
1297                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1298
1299         /*
1300          * This works for seqpacket too. The receiver has ordered the queue for
1301          * us! We do one quick check first though
1302          */
1303         if (sk->sk_state != TCP_ESTABLISHED)
1304                 goto out;
1305
1306         if (flags & MSG_OOB) {
1307                 rc = -EINVAL;
1308                 if (sock_flag(sk, SOCK_URGINLINE) ||
1309                     !skb_peek(&x25->interrupt_in_queue))
1310                         goto out;
1311
1312                 skb = skb_dequeue(&x25->interrupt_in_queue);
1313
1314                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1315                         goto out_free_dgram;
1316
1317                 skb_pull(skb, X25_STD_MIN_LEN);
1318
1319                 /*
1320                  *      No Q bit information on Interrupt data.
1321                  */
1322                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1323                         asmptr  = skb_push(skb, 1);
1324                         *asmptr = 0x00;
1325                 }
1326
1327                 msg->msg_flags |= MSG_OOB;
1328         } else {
1329                 /* Now we can treat all alike */
1330                 release_sock(sk);
1331                 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1332                                         flags & MSG_DONTWAIT, &rc);
1333                 lock_sock(sk);
1334                 if (!skb)
1335                         goto out;
1336
1337                 if (!pskb_may_pull(skb, header_len))
1338                         goto out_free_dgram;
1339
1340                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1341
1342                 skb_pull(skb, header_len);
1343
1344                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1345                         asmptr  = skb_push(skb, 1);
1346                         *asmptr = qbit;
1347                 }
1348         }
1349
1350         skb_reset_transport_header(skb);
1351         copied = skb->len;
1352
1353         if (copied > size) {
1354                 copied = size;
1355                 msg->msg_flags |= MSG_TRUNC;
1356         }
1357
1358         /* Currently, each datagram always contains a complete record */
1359         msg->msg_flags |= MSG_EOR;
1360
1361         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1362         if (rc)
1363                 goto out_free_dgram;
1364
1365         if (sx25) {
1366                 sx25->sx25_family = AF_X25;
1367                 sx25->sx25_addr   = x25->dest_addr;
1368                 msg->msg_namelen = sizeof(*sx25);
1369         }
1370
1371         x25_check_rbuf(sk);
1372         rc = copied;
1373 out_free_dgram:
1374         skb_free_datagram(sk, skb);
1375 out:
1376         release_sock(sk);
1377         return rc;
1378 }
1379
1380
1381 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1382 {
1383         struct sock *sk = sock->sk;
1384         struct x25_sock *x25 = x25_sk(sk);
1385         void __user *argp = (void __user *)arg;
1386         int rc;
1387
1388         switch (cmd) {
1389         case TIOCOUTQ: {
1390                 int amount;
1391
1392                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1393                 if (amount < 0)
1394                         amount = 0;
1395                 rc = put_user(amount, (unsigned int __user *)argp);
1396                 break;
1397         }
1398
1399         case TIOCINQ: {
1400                 struct sk_buff *skb;
1401                 int amount = 0;
1402                 /*
1403                  * These two are safe on a single CPU system as
1404                  * only user tasks fiddle here
1405                  */
1406                 lock_sock(sk);
1407                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1408                         amount = skb->len;
1409                 release_sock(sk);
1410                 rc = put_user(amount, (unsigned int __user *)argp);
1411                 break;
1412         }
1413
1414         case SIOCGSTAMP:
1415                 rc = -EINVAL;
1416                 if (sk)
1417                         rc = sock_get_timestamp(sk,
1418                                                 (struct timeval __user *)argp);
1419                 break;
1420         case SIOCGSTAMPNS:
1421                 rc = -EINVAL;
1422                 if (sk)
1423                         rc = sock_get_timestampns(sk,
1424                                         (struct timespec __user *)argp);
1425                 break;
1426         case SIOCGIFADDR:
1427         case SIOCSIFADDR:
1428         case SIOCGIFDSTADDR:
1429         case SIOCSIFDSTADDR:
1430         case SIOCGIFBRDADDR:
1431         case SIOCSIFBRDADDR:
1432         case SIOCGIFNETMASK:
1433         case SIOCSIFNETMASK:
1434         case SIOCGIFMETRIC:
1435         case SIOCSIFMETRIC:
1436                 rc = -EINVAL;
1437                 break;
1438         case SIOCADDRT:
1439         case SIOCDELRT:
1440                 rc = -EPERM;
1441                 if (!capable(CAP_NET_ADMIN))
1442                         break;
1443                 rc = x25_route_ioctl(cmd, argp);
1444                 break;
1445         case SIOCX25GSUBSCRIP:
1446                 rc = x25_subscr_ioctl(cmd, argp);
1447                 break;
1448         case SIOCX25SSUBSCRIP:
1449                 rc = -EPERM;
1450                 if (!capable(CAP_NET_ADMIN))
1451                         break;
1452                 rc = x25_subscr_ioctl(cmd, argp);
1453                 break;
1454         case SIOCX25GFACILITIES: {
1455                 lock_sock(sk);
1456                 rc = copy_to_user(argp, &x25->facilities,
1457                                   sizeof(x25->facilities))
1458                         ? -EFAULT : 0;
1459                 release_sock(sk);
1460                 break;
1461         }
1462
1463         case SIOCX25SFACILITIES: {
1464                 struct x25_facilities facilities;
1465                 rc = -EFAULT;
1466                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1467                         break;
1468                 rc = -EINVAL;
1469                 lock_sock(sk);
1470                 if (sk->sk_state != TCP_LISTEN &&
1471                     sk->sk_state != TCP_CLOSE)
1472                         goto out_fac_release;
1473                 if (facilities.pacsize_in < X25_PS16 ||
1474                     facilities.pacsize_in > X25_PS4096)
1475                         goto out_fac_release;
1476                 if (facilities.pacsize_out < X25_PS16 ||
1477                     facilities.pacsize_out > X25_PS4096)
1478                         goto out_fac_release;
1479                 if (facilities.winsize_in < 1 ||
1480                     facilities.winsize_in > 127)
1481                         goto out_fac_release;
1482                 if (facilities.throughput) {
1483                         int out = facilities.throughput & 0xf0;
1484                         int in  = facilities.throughput & 0x0f;
1485                         if (!out)
1486                                 facilities.throughput |=
1487                                         X25_DEFAULT_THROUGHPUT << 4;
1488                         else if (out < 0x30 || out > 0xD0)
1489                                 goto out_fac_release;
1490                         if (!in)
1491                                 facilities.throughput |=
1492                                         X25_DEFAULT_THROUGHPUT;
1493                         else if (in < 0x03 || in > 0x0D)
1494                                 goto out_fac_release;
1495                 }
1496                 if (facilities.reverse &&
1497                     (facilities.reverse & 0x81) != 0x81)
1498                         goto out_fac_release;
1499                 x25->facilities = facilities;
1500                 rc = 0;
1501 out_fac_release:
1502                 release_sock(sk);
1503                 break;
1504         }
1505
1506         case SIOCX25GDTEFACILITIES: {
1507                 lock_sock(sk);
1508                 rc = copy_to_user(argp, &x25->dte_facilities,
1509                                   sizeof(x25->dte_facilities));
1510                 release_sock(sk);
1511                 if (rc)
1512                         rc = -EFAULT;
1513                 break;
1514         }
1515
1516         case SIOCX25SDTEFACILITIES: {
1517                 struct x25_dte_facilities dtefacs;
1518                 rc = -EFAULT;
1519                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1520                         break;
1521                 rc = -EINVAL;
1522                 lock_sock(sk);
1523                 if (sk->sk_state != TCP_LISTEN &&
1524                     sk->sk_state != TCP_CLOSE)
1525                         goto out_dtefac_release;
1526                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1527                         goto out_dtefac_release;
1528                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1529                         goto out_dtefac_release;
1530                 x25->dte_facilities = dtefacs;
1531                 rc = 0;
1532 out_dtefac_release:
1533                 release_sock(sk);
1534                 break;
1535         }
1536
1537         case SIOCX25GCALLUSERDATA: {
1538                 lock_sock(sk);
1539                 rc = copy_to_user(argp, &x25->calluserdata,
1540                                   sizeof(x25->calluserdata))
1541                         ? -EFAULT : 0;
1542                 release_sock(sk);
1543                 break;
1544         }
1545
1546         case SIOCX25SCALLUSERDATA: {
1547                 struct x25_calluserdata calluserdata;
1548
1549                 rc = -EFAULT;
1550                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1551                         break;
1552                 rc = -EINVAL;
1553                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1554                         break;
1555                 lock_sock(sk);
1556                 x25->calluserdata = calluserdata;
1557                 release_sock(sk);
1558                 rc = 0;
1559                 break;
1560         }
1561
1562         case SIOCX25GCAUSEDIAG: {
1563                 lock_sock(sk);
1564                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1565                         ? -EFAULT : 0;
1566                 release_sock(sk);
1567                 break;
1568         }
1569
1570         case SIOCX25SCAUSEDIAG: {
1571                 struct x25_causediag causediag;
1572                 rc = -EFAULT;
1573                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1574                         break;
1575                 lock_sock(sk);
1576                 x25->causediag = causediag;
1577                 release_sock(sk);
1578                 rc = 0;
1579                 break;
1580
1581         }
1582
1583         case SIOCX25SCUDMATCHLEN: {
1584                 struct x25_subaddr sub_addr;
1585                 rc = -EINVAL;
1586                 lock_sock(sk);
1587                 if(sk->sk_state != TCP_CLOSE)
1588                         goto out_cud_release;
1589                 rc = -EFAULT;
1590                 if (copy_from_user(&sub_addr, argp,
1591                                    sizeof(sub_addr)))
1592                         goto out_cud_release;
1593                 rc = -EINVAL;
1594                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1595                         goto out_cud_release;
1596                 x25->cudmatchlength = sub_addr.cudmatchlength;
1597                 rc = 0;
1598 out_cud_release:
1599                 release_sock(sk);
1600                 break;
1601         }
1602
1603         case SIOCX25CALLACCPTAPPRV: {
1604                 rc = -EINVAL;
1605                 lock_sock(sk);
1606                 if (sk->sk_state == TCP_CLOSE) {
1607                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1608                         rc = 0;
1609                 }
1610                 release_sock(sk);
1611                 break;
1612         }
1613
1614         case SIOCX25SENDCALLACCPT:  {
1615                 rc = -EINVAL;
1616                 lock_sock(sk);
1617                 if (sk->sk_state != TCP_ESTABLISHED)
1618                         goto out_sendcallaccpt_release;
1619                 /* must call accptapprv above */
1620                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1621                         goto out_sendcallaccpt_release;
1622                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1623                 x25->state = X25_STATE_3;
1624                 rc = 0;
1625 out_sendcallaccpt_release:
1626                 release_sock(sk);
1627                 break;
1628         }
1629
1630         default:
1631                 rc = -ENOIOCTLCMD;
1632                 break;
1633         }
1634
1635         return rc;
1636 }
1637
1638 static const struct net_proto_family x25_family_ops = {
1639         .family =       AF_X25,
1640         .create =       x25_create,
1641         .owner  =       THIS_MODULE,
1642 };
1643
1644 #ifdef CONFIG_COMPAT
1645 static int compat_x25_subscr_ioctl(unsigned int cmd,
1646                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1647 {
1648         struct compat_x25_subscrip_struct x25_subscr;
1649         struct x25_neigh *nb;
1650         struct net_device *dev;
1651         int rc = -EINVAL;
1652
1653         rc = -EFAULT;
1654         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1655                 goto out;
1656
1657         rc = -EINVAL;
1658         dev = x25_dev_get(x25_subscr.device);
1659         if (dev == NULL)
1660                 goto out;
1661
1662         nb = x25_get_neigh(dev);
1663         if (nb == NULL)
1664                 goto out_dev_put;
1665
1666         dev_put(dev);
1667
1668         if (cmd == SIOCX25GSUBSCRIP) {
1669                 read_lock_bh(&x25_neigh_list_lock);
1670                 x25_subscr.extended = nb->extended;
1671                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1672                 read_unlock_bh(&x25_neigh_list_lock);
1673                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1674                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1675         } else {
1676                 rc = -EINVAL;
1677                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1678                         rc = 0;
1679                         write_lock_bh(&x25_neigh_list_lock);
1680                         nb->extended = x25_subscr.extended;
1681                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1682                         write_unlock_bh(&x25_neigh_list_lock);
1683                 }
1684         }
1685         x25_neigh_put(nb);
1686 out:
1687         return rc;
1688 out_dev_put:
1689         dev_put(dev);
1690         goto out;
1691 }
1692
1693 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1694                                 unsigned long arg)
1695 {
1696         void __user *argp = compat_ptr(arg);
1697         struct sock *sk = sock->sk;
1698
1699         int rc = -ENOIOCTLCMD;
1700
1701         switch(cmd) {
1702         case TIOCOUTQ:
1703         case TIOCINQ:
1704                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1705                 break;
1706         case SIOCGSTAMP:
1707                 rc = -EINVAL;
1708                 if (sk)
1709                         rc = compat_sock_get_timestamp(sk,
1710                                         (struct timeval __user*)argp);
1711                 break;
1712         case SIOCGSTAMPNS:
1713                 rc = -EINVAL;
1714                 if (sk)
1715                         rc = compat_sock_get_timestampns(sk,
1716                                         (struct timespec __user*)argp);
1717                 break;
1718         case SIOCGIFADDR:
1719         case SIOCSIFADDR:
1720         case SIOCGIFDSTADDR:
1721         case SIOCSIFDSTADDR:
1722         case SIOCGIFBRDADDR:
1723         case SIOCSIFBRDADDR:
1724         case SIOCGIFNETMASK:
1725         case SIOCSIFNETMASK:
1726         case SIOCGIFMETRIC:
1727         case SIOCSIFMETRIC:
1728                 rc = -EINVAL;
1729                 break;
1730         case SIOCADDRT:
1731         case SIOCDELRT:
1732                 rc = -EPERM;
1733                 if (!capable(CAP_NET_ADMIN))
1734                         break;
1735                 rc = x25_route_ioctl(cmd, argp);
1736                 break;
1737         case SIOCX25GSUBSCRIP:
1738                 rc = compat_x25_subscr_ioctl(cmd, argp);
1739                 break;
1740         case SIOCX25SSUBSCRIP:
1741                 rc = -EPERM;
1742                 if (!capable(CAP_NET_ADMIN))
1743                         break;
1744                 rc = compat_x25_subscr_ioctl(cmd, argp);
1745                 break;
1746         case SIOCX25GFACILITIES:
1747         case SIOCX25SFACILITIES:
1748         case SIOCX25GDTEFACILITIES:
1749         case SIOCX25SDTEFACILITIES:
1750         case SIOCX25GCALLUSERDATA:
1751         case SIOCX25SCALLUSERDATA:
1752         case SIOCX25GCAUSEDIAG:
1753         case SIOCX25SCAUSEDIAG:
1754         case SIOCX25SCUDMATCHLEN:
1755         case SIOCX25CALLACCPTAPPRV:
1756         case SIOCX25SENDCALLACCPT:
1757                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1758                 break;
1759         default:
1760                 rc = -ENOIOCTLCMD;
1761                 break;
1762         }
1763         return rc;
1764 }
1765 #endif
1766
1767 static const struct proto_ops x25_proto_ops = {
1768         .family =       AF_X25,
1769         .owner =        THIS_MODULE,
1770         .release =      x25_release,
1771         .bind =         x25_bind,
1772         .connect =      x25_connect,
1773         .socketpair =   sock_no_socketpair,
1774         .accept =       x25_accept,
1775         .getname =      x25_getname,
1776         .poll =         datagram_poll,
1777         .ioctl =        x25_ioctl,
1778 #ifdef CONFIG_COMPAT
1779         .compat_ioctl = compat_x25_ioctl,
1780 #endif
1781         .listen =       x25_listen,
1782         .shutdown =     sock_no_shutdown,
1783         .setsockopt =   x25_setsockopt,
1784         .getsockopt =   x25_getsockopt,
1785         .sendmsg =      x25_sendmsg,
1786         .recvmsg =      x25_recvmsg,
1787         .mmap =         sock_no_mmap,
1788         .sendpage =     sock_no_sendpage,
1789 };
1790
1791 static struct packet_type x25_packet_type __read_mostly = {
1792         .type = cpu_to_be16(ETH_P_X25),
1793         .func = x25_lapb_receive_frame,
1794 };
1795
1796 static struct notifier_block x25_dev_notifier = {
1797         .notifier_call = x25_device_event,
1798 };
1799
1800 void x25_kill_by_neigh(struct x25_neigh *nb)
1801 {
1802         struct sock *s;
1803
1804         write_lock_bh(&x25_list_lock);
1805
1806         sk_for_each(s, &x25_list) {
1807                 if (x25_sk(s)->neighbour == nb) {
1808                         write_unlock_bh(&x25_list_lock);
1809                         lock_sock(s);
1810                         x25_disconnect(s, ENETUNREACH, 0, 0);
1811                         release_sock(s);
1812                         write_lock_bh(&x25_list_lock);
1813                 }
1814         }
1815         write_unlock_bh(&x25_list_lock);
1816
1817         /* Remove any related forwards */
1818         x25_clear_forward_by_dev(nb->dev);
1819 }
1820
1821 static int __init x25_init(void)
1822 {
1823         int rc;
1824
1825         rc = proto_register(&x25_proto, 0);
1826         if (rc)
1827                 goto out;
1828
1829         rc = sock_register(&x25_family_ops);
1830         if (rc)
1831                 goto out_proto;
1832
1833         dev_add_pack(&x25_packet_type);
1834
1835         rc = register_netdevice_notifier(&x25_dev_notifier);
1836         if (rc)
1837                 goto out_sock;
1838
1839         rc = x25_register_sysctl();
1840         if (rc)
1841                 goto out_dev;
1842
1843         rc = x25_proc_init();
1844         if (rc)
1845                 goto out_sysctl;
1846
1847         pr_info("Linux Version 0.2\n");
1848
1849 out:
1850         return rc;
1851 out_sysctl:
1852         x25_unregister_sysctl();
1853 out_dev:
1854         unregister_netdevice_notifier(&x25_dev_notifier);
1855 out_sock:
1856         dev_remove_pack(&x25_packet_type);
1857         sock_unregister(AF_X25);
1858 out_proto:
1859         proto_unregister(&x25_proto);
1860         goto out;
1861 }
1862 module_init(x25_init);
1863
1864 static void __exit x25_exit(void)
1865 {
1866         x25_proc_exit();
1867         x25_link_free();
1868         x25_route_free();
1869
1870         x25_unregister_sysctl();
1871
1872         unregister_netdevice_notifier(&x25_dev_notifier);
1873
1874         dev_remove_pack(&x25_packet_type);
1875
1876         sock_unregister(AF_X25);
1877         proto_unregister(&x25_proto);
1878 }
1879 module_exit(x25_exit);
1880
1881 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1882 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1883 MODULE_LICENSE("GPL");
1884 MODULE_ALIAS_NETPROTO(PF_X25);