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  *      Handle device status changes.
 204  */
 205 static int x25_device_event(struct notifier_block *this, unsigned long event,
 206                             void *ptr)
 207 {
 208         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 209         struct x25_neigh *nb;
 210
 211         if (!net_eq(dev_net(dev), &init_net))
 212                 return NOTIFY_DONE;
 213
 214         if (dev->type == ARPHRD_X25) {
 215                 switch (event) {
 216                 case NETDEV_REGISTER:
 217                 case NETDEV_POST_TYPE_CHANGE:
 218                         x25_link_device_up(dev);
 219                         break;
 220                 case NETDEV_DOWN:
 221                         nb = x25_get_neigh(dev);
 222                         if (nb) {
 223                                 x25_link_terminated(nb);
 224                                 x25_neigh_put(nb);
 225                         }
 226                         x25_route_device_down(dev);
 227                         break;
 228                 case NETDEV_PRE_TYPE_CHANGE:
 229                 case NETDEV_UNREGISTER:
 230                         x25_link_device_down(dev);
 231                         break;
 232                 case NETDEV_CHANGE:
 233                         if (!netif_carrier_ok(dev)) {
 234                                 nb = x25_get_neigh(dev);
 235                                 if (nb) {
 236                                         x25_link_terminated(nb);
 237                                         x25_neigh_put(nb);
 238                                 }
 239                         }
 240                         break;
 241                 }
 242         }
 243
 244         return NOTIFY_DONE;
 245 }
 246
 247 /*
 248  *      Add a socket to the bound sockets list.
 249  */
 250 static void x25_insert_socket(struct sock *sk)
 251 {
 252         write_lock_bh(&x25_list_lock);
 253         sk_add_node(sk, &x25_list);
 254         write_unlock_bh(&x25_list_lock);
 255 }
 256
 257 /*
 258  *      Find a socket that wants to accept the Call Request we just
 259  *      received. Check the full list for an address/cud match.
 260  *      If no cuds match return the next_best thing, an address match.
 261  *      Note: if a listening socket has cud set it must only get calls
 262  *      with matching cud.
 263  */
 264 static struct sock *x25_find_listener(struct x25_address *addr,
 265                                         struct sk_buff *skb)
 266 {
 267         struct sock *s;
 268         struct sock *next_best;
 269
 270         read_lock_bh(&x25_list_lock);
 271         next_best = NULL;
 272
 273         sk_for_each(s, &x25_list)
 274                 if ((!strcmp(addr->x25_addr,
 275                         x25_sk(s)->source_addr.x25_addr) ||
 276                                 !strcmp(x25_sk(s)->source_addr.x25_addr,
 277                                         null_x25_address.x25_addr)) &&
 278                                         s->sk_state == TCP_LISTEN) {
 279                         /*
 280                          * Found a listening socket, now check the incoming
 281                          * call user data vs this sockets call user data
 282                          */
 283                         if (x25_sk(s)->cudmatchlength > 0 &&
 284                                 skb->len >= x25_sk(s)->cudmatchlength) {
 285                                 if((memcmp(x25_sk(s)->calluserdata.cuddata,
 286                                         skb->data,
 287                                         x25_sk(s)->cudmatchlength)) == 0) {
 288                                         sock_hold(s);
 289                                         goto found;
 290                                  }
 291                         } else
 292                                 next_best = s;
 293                 }
 294         if (next_best) {
 295                 s = next_best;
 296                 sock_hold(s);
 297                 goto found;
 298         }
 299         s = NULL;
 300 found:
 301         read_unlock_bh(&x25_list_lock);
 302         return s;
 303 }
 304
 305 /*
 306  *      Find a connected X.25 socket given my LCI and neighbour.
 307  */
 308 static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 309 {
 310         struct sock *s;
 311
 312         sk_for_each(s, &x25_list)
 313                 if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
 314                         sock_hold(s);
 315                         goto found;
 316                 }
 317         s = NULL;
 318 found:
 319         return s;
 320 }
 321
 322 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 323 {
 324         struct sock *s;
 325
 326         read_lock_bh(&x25_list_lock);
 327         s = __x25_find_socket(lci, nb);
 328         read_unlock_bh(&x25_list_lock);
 329         return s;
 330 }
 331
 332 /*
 333  *      Find a unique LCI for a given device.
 334  */
 335 static unsigned int x25_new_lci(struct x25_neigh *nb)
 336 {
 337         unsigned int lci = 1;
 338         struct sock *sk;
 339
 340         while ((sk = x25_find_socket(lci, nb)) != NULL) {
 341                 sock_put(sk);
 342                 if (++lci == 4096) {
 343                         lci = 0;
 344                         break;
 345                 }
 346                 cond_resched();
 347         }
 348
 349         return lci;
 350 }
 351
 352 /*
 353  *      Deferred destroy.
 354  */
 355 static void __x25_destroy_socket(struct sock *);
 356
 357 /*
 358  *      handler for deferred kills.
 359  */
 360 static void x25_destroy_timer(struct timer_list *t)
 361 {
 362         struct sock *sk = from_timer(sk, t, sk_timer);
 363
 364         x25_destroy_socket_from_timer(sk);
 365 }
 366
 367 /*
 368  *      This is called from user mode and the timers. Thus it protects itself
 369  *      against interrupting users but doesn't worry about being called during
 370  *      work. Once it is removed from the queue no interrupt or bottom half
 371  *      will touch it and we are (fairly 8-) ) safe.
 372  *      Not static as it's used by the timer
 373  */
 374 static void __x25_destroy_socket(struct sock *sk)
 375 {
 376         struct sk_buff *skb;
 377
 378         x25_stop_heartbeat(sk);
 379         x25_stop_timer(sk);
 380
 381         x25_remove_socket(sk);
 382         x25_clear_queues(sk);           /* Flush the queues */
 383
 384         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 385                 if (skb->sk != sk) {            /* A pending connection */
 386                         /*
 387                          * Queue the unaccepted socket for death
 388                          */
 389                         skb->sk->sk_state = TCP_LISTEN;
 390                         sock_set_flag(skb->sk, SOCK_DEAD);
 391                         x25_start_heartbeat(skb->sk);
 392                         x25_sk(skb->sk)->state = X25_STATE_0;
 393                 }
 394
 395                 kfree_skb(skb);
 396         }
 397
 398         if (sk_has_allocations(sk)) {
 399                 /* Defer: outstanding buffers */
 400                 sk->sk_timer.expires  = jiffies + 10 * HZ;
 401                 sk->sk_timer.function = x25_destroy_timer;
 402                 add_timer(&sk->sk_timer);
 403         } else {
 404                 /* drop last reference so sock_put will free */
 405                 __sock_put(sk);
 406         }
 407 }
 408
 409 void x25_destroy_socket_from_timer(struct sock *sk)
 410 {
 411         sock_hold(sk);
 412         bh_lock_sock(sk);
 413         __x25_destroy_socket(sk);
 414         bh_unlock_sock(sk);
 415         sock_put(sk);
 416 }
 417
 418 /*
 419  *      Handling for system calls applied via the various interfaces to a
 420  *      X.25 socket object.
 421  */
 422
 423 static int x25_setsockopt(struct socket *sock, int level, int optname,
 424                           sockptr_t optval, unsigned int optlen)
 425 {
 426         int opt;
 427         struct sock *sk = sock->sk;
 428         int rc = -ENOPROTOOPT;
 429
 430         if (level != SOL_X25 || optname != X25_QBITINCL)
 431                 goto out;
 432
 433         rc = -EINVAL;
 434         if (optlen < sizeof(int))
 435                 goto out;
 436
 437         rc = -EFAULT;
 438         if (copy_from_sockptr(&opt, optval, sizeof(int)))
 439                 goto out;
 440
 441         if (opt)
 442                 set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 443         else
 444                 clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 445         rc = 0;
 446 out:
 447         return rc;
 448 }
 449
 450 static int x25_getsockopt(struct socket *sock, int level, int optname,
 451                           char __user *optval, int __user *optlen)
 452 {
 453         struct sock *sk = sock->sk;
 454         int val, len, rc = -ENOPROTOOPT;
 455
 456         if (level != SOL_X25 || optname != X25_QBITINCL)
 457                 goto out;
 458
 459         rc = -EFAULT;
 460         if (get_user(len, optlen))
 461                 goto out;
 462
 463         len = min_t(unsigned int, len, sizeof(int));
 464
 465         rc = -EINVAL;
 466         if (len < 0)
 467                 goto out;
 468
 469         rc = -EFAULT;
 470         if (put_user(len, optlen))
 471                 goto out;
 472
 473         val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 474         rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
 475 out:
 476         return rc;
 477 }
 478
 479 static int x25_listen(struct socket *sock, int backlog)
 480 {
 481         struct sock *sk = sock->sk;
 482         int rc = -EOPNOTSUPP;
 483
 484         lock_sock(sk);
 485         if (sock->state != SS_UNCONNECTED) {
 486                 rc = -EINVAL;
 487                 release_sock(sk);
 488                 return rc;
 489         }
 490
 491         if (sk->sk_state != TCP_LISTEN) {
 492                 memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 493                 sk->sk_max_ack_backlog = backlog;
 494                 sk->sk_state           = TCP_LISTEN;
 495                 rc = 0;
 496         }
 497         release_sock(sk);
 498
 499         return rc;
 500 }
 501
 502 static struct proto x25_proto = {
 503         .name     = "X25",
 504         .owner    = THIS_MODULE,
 505         .obj_size = sizeof(struct x25_sock),
 506 };
 507
 508 static struct sock *x25_alloc_socket(struct net *net, int kern)
 509 {
 510         struct x25_sock *x25;
 511         struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 512
 513         if (!sk)
 514                 goto out;
 515
 516         sock_init_data(NULL, sk);
 517
 518         x25 = x25_sk(sk);
 519         skb_queue_head_init(&x25->ack_queue);
 520         skb_queue_head_init(&x25->fragment_queue);
 521         skb_queue_head_init(&x25->interrupt_in_queue);
 522         skb_queue_head_init(&x25->interrupt_out_queue);
 523 out:
 524         return sk;
 525 }
 526
 527 static int x25_create(struct net *net, struct socket *sock, int protocol,
 528                       int kern)
 529 {
 530         struct sock *sk;
 531         struct x25_sock *x25;
 532         int rc = -EAFNOSUPPORT;
 533
 534         if (!net_eq(net, &init_net))
 535                 goto out;
 536
 537         rc = -ESOCKTNOSUPPORT;
 538         if (sock->type != SOCK_SEQPACKET)
 539                 goto out;
 540
 541         rc = -EINVAL;
 542         if (protocol)
 543                 goto out;
 544
 545         rc = -ENOMEM;
 546         if ((sk = x25_alloc_socket(net, kern)) == NULL)
 547                 goto out;
 548
 549         x25 = x25_sk(sk);
 550
 551         sock_init_data(sock, sk);
 552
 553         x25_init_timers(sk);
 554
 555         sock->ops    = &x25_proto_ops;
 556         sk->sk_protocol = protocol;
 557         sk->sk_backlog_rcv = x25_backlog_rcv;
 558
 559         x25->t21   = sysctl_x25_call_request_timeout;
 560         x25->t22   = sysctl_x25_reset_request_timeout;
 561         x25->t23   = sysctl_x25_clear_request_timeout;
 562         x25->t2    = sysctl_x25_ack_holdback_timeout;
 563         x25->state = X25_STATE_0;
 564         x25->cudmatchlength = 0;
 565         set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);     /* normally no cud  */
 566                                                         /* on call accept   */
 567
 568         x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 569         x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 570         x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 571         x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 572         x25->facilities.throughput  = 0;        /* by default don't negotiate
 573                                                    throughput */
 574         x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 575         x25->dte_facilities.calling_len = 0;
 576         x25->dte_facilities.called_len = 0;
 577         memset(x25->dte_facilities.called_ae, '\0',
 578                         sizeof(x25->dte_facilities.called_ae));
 579         memset(x25->dte_facilities.calling_ae, '\0',
 580                         sizeof(x25->dte_facilities.calling_ae));
 581
 582         rc = 0;
 583 out:
 584         return rc;
 585 }
 586
 587 static struct sock *x25_make_new(struct sock *osk)
 588 {
 589         struct sock *sk = NULL;
 590         struct x25_sock *x25, *ox25;
 591
 592         if (osk->sk_type != SOCK_SEQPACKET)
 593                 goto out;
 594
 595         if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 596                 goto out;
 597
 598         x25 = x25_sk(sk);
 599
 600         sk->sk_type        = osk->sk_type;
 601         sk->sk_priority    = osk->sk_priority;
 602         sk->sk_protocol    = osk->sk_protocol;
 603         sk->sk_rcvbuf      = osk->sk_rcvbuf;
 604         sk->sk_sndbuf      = osk->sk_sndbuf;
 605         sk->sk_state       = TCP_ESTABLISHED;
 606         sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 607         sock_copy_flags(sk, osk);
 608
 609         ox25 = x25_sk(osk);
 610         x25->t21        = ox25->t21;
 611         x25->t22        = ox25->t22;
 612         x25->t23        = ox25->t23;
 613         x25->t2         = ox25->t2;
 614         x25->flags      = ox25->flags;
 615         x25->facilities = ox25->facilities;
 616         x25->dte_facilities = ox25->dte_facilities;
 617         x25->cudmatchlength = ox25->cudmatchlength;
 618
 619         clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 620         x25_init_timers(sk);
 621 out:
 622         return sk;
 623 }
 624
 625 static int x25_release(struct socket *sock)
 626 {
 627         struct sock *sk = sock->sk;
 628         struct x25_sock *x25;
 629
 630         if (!sk)
 631                 return 0;
 632
 633         x25 = x25_sk(sk);
 634
 635         sock_hold(sk);
 636         lock_sock(sk);
 637         switch (x25->state) {
 638
 639                 case X25_STATE_0:
 640                 case X25_STATE_2:
 641                         x25_disconnect(sk, 0, 0, 0);
 642                         __x25_destroy_socket(sk);
 643                         goto out;
 644
 645                 case X25_STATE_1:
 646                 case X25_STATE_3:
 647                 case X25_STATE_4:
 648                         x25_clear_queues(sk);
 649                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 650                         x25_start_t23timer(sk);
 651                         x25->state = X25_STATE_2;
 652                         sk->sk_state    = TCP_CLOSE;
 653                         sk->sk_shutdown |= SEND_SHUTDOWN;
 654                         sk->sk_state_change(sk);
 655                         sock_set_flag(sk, SOCK_DEAD);
 656                         sock_set_flag(sk, SOCK_DESTROY);
 657                         break;
 658
 659                 case X25_STATE_5:
 660                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 661                         x25_disconnect(sk, 0, 0, 0);
 662                         __x25_destroy_socket(sk);
 663                         goto out;
 664         }
 665
 666         sock_orphan(sk);
 667 out:
 668         release_sock(sk);
 669         sock_put(sk);
 670         return 0;
 671 }
 672
 673 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 674 {
 675         struct sock *sk = sock->sk;
 676         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 677         int len, i, rc = 0;
 678
 679         if (addr_len != sizeof(struct sockaddr_x25) ||
 680             addr->sx25_family != AF_X25 ||
 681             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) {
 682                 rc = -EINVAL;
 683                 goto out;
 684         }
 685
 686         /* check for the null_x25_address */
 687         if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
 688
 689                 len = strlen(addr->sx25_addr.x25_addr);
 690                 for (i = 0; i < len; i++) {
 691                         if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 692                                 rc = -EINVAL;
 693                                 goto out;
 694                         }
 695                 }
 696         }
 697
 698         lock_sock(sk);
 699         if (sock_flag(sk, SOCK_ZAPPED)) {
 700                 x25_sk(sk)->source_addr = addr->sx25_addr;
 701                 x25_insert_socket(sk);
 702                 sock_reset_flag(sk, SOCK_ZAPPED);
 703         } else {
 704                 rc = -EINVAL;
 705         }
 706         release_sock(sk);
 707         SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
 708 out:
 709         return rc;
 710 }
 711
 712 static int x25_wait_for_connection_establishment(struct sock *sk)
 713 {
 714         DECLARE_WAITQUEUE(wait, current);
 715         int rc;
 716
 717         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 718         for (;;) {
 719                 __set_current_state(TASK_INTERRUPTIBLE);
 720                 rc = -ERESTARTSYS;
 721                 if (signal_pending(current))
 722                         break;
 723                 rc = sock_error(sk);
 724                 if (rc) {
 725                         sk->sk_socket->state = SS_UNCONNECTED;
 726                         break;
 727                 }
 728                 rc = -ENOTCONN;
 729                 if (sk->sk_state == TCP_CLOSE) {
 730                         sk->sk_socket->state = SS_UNCONNECTED;
 731                         break;
 732                 }
 733                 rc = 0;
 734                 if (sk->sk_state != TCP_ESTABLISHED) {
 735                         release_sock(sk);
 736                         schedule();
 737                         lock_sock(sk);
 738                 } else
 739                         break;
 740         }
 741         __set_current_state(TASK_RUNNING);
 742         remove_wait_queue(sk_sleep(sk), &wait);
 743         return rc;
 744 }
 745
 746 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
 747                        int addr_len, int flags)
 748 {
 749         struct sock *sk = sock->sk;
 750         struct x25_sock *x25 = x25_sk(sk);
 751         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 752         struct x25_route *rt;
 753         int rc = 0;
 754
 755         lock_sock(sk);
 756         if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 757                 sock->state = SS_CONNECTED;
 758                 goto out; /* Connect completed during a ERESTARTSYS event */
 759         }
 760
 761         rc = -ECONNREFUSED;
 762         if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 763                 sock->state = SS_UNCONNECTED;
 764                 goto out;
 765         }
 766
 767         rc = -EISCONN;  /* No reconnect on a seqpacket socket */
 768         if (sk->sk_state == TCP_ESTABLISHED)
 769                 goto out;
 770
 771         rc = -EALREADY; /* Do nothing if call is already in progress */
 772         if (sk->sk_state == TCP_SYN_SENT)
 773                 goto out;
 774
 775         sk->sk_state   = TCP_CLOSE;
 776         sock->state = SS_UNCONNECTED;
 777
 778         rc = -EINVAL;
 779         if (addr_len != sizeof(struct sockaddr_x25) ||
 780             addr->sx25_family != AF_X25 ||
 781             strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN)
 782                 goto out;
 783
 784         rc = -ENETUNREACH;
 785         rt = x25_get_route(&addr->sx25_addr);
 786         if (!rt)
 787                 goto out;
 788
 789         x25->neighbour = x25_get_neigh(rt->dev);
 790         if (!x25->neighbour)
 791                 goto out_put_route;
 792
 793         x25_limit_facilities(&x25->facilities, x25->neighbour);
 794
 795         x25->lci = x25_new_lci(x25->neighbour);
 796         if (!x25->lci)
 797                 goto out_put_neigh;
 798
 799         rc = -EINVAL;
 800         if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 801                 goto out_put_neigh;
 802
 803         if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 804                 memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 805
 806         x25->dest_addr = addr->sx25_addr;
 807
 808         /* Move to connecting socket, start sending Connect Requests */
 809         sock->state   = SS_CONNECTING;
 810         sk->sk_state  = TCP_SYN_SENT;
 811
 812         x25->state = X25_STATE_1;
 813
 814         x25_write_internal(sk, X25_CALL_REQUEST);
 815
 816         x25_start_heartbeat(sk);
 817         x25_start_t21timer(sk);
 818
 819         /* Now the loop */
 820         rc = -EINPROGRESS;
 821         if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 822                 goto out;
 823
 824         rc = x25_wait_for_connection_establishment(sk);
 825         if (rc)
 826                 goto out_put_neigh;
 827
 828         sock->state = SS_CONNECTED;
 829         rc = 0;
 830 out_put_neigh:
 831         if (rc && x25->neighbour) {
 832                 read_lock_bh(&x25_list_lock);
 833                 x25_neigh_put(x25->neighbour);
 834                 x25->neighbour = NULL;
 835                 read_unlock_bh(&x25_list_lock);
 836                 x25->state = X25_STATE_0;
 837         }
 838 out_put_route:
 839         x25_route_put(rt);
 840 out:
 841         release_sock(sk);
 842         return rc;
 843 }
 844
 845 static int x25_wait_for_data(struct sock *sk, long timeout)
 846 {
 847         DECLARE_WAITQUEUE(wait, current);
 848         int rc = 0;
 849
 850         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 851         for (;;) {
 852                 __set_current_state(TASK_INTERRUPTIBLE);
 853                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 854                         break;
 855                 rc = -ERESTARTSYS;
 856                 if (signal_pending(current))
 857                         break;
 858                 rc = -EAGAIN;
 859                 if (!timeout)
 860                         break;
 861                 rc = 0;
 862                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 863                         release_sock(sk);
 864                         timeout = schedule_timeout(timeout);
 865                         lock_sock(sk);
 866                 } else
 867                         break;
 868         }
 869         __set_current_state(TASK_RUNNING);
 870         remove_wait_queue(sk_sleep(sk), &wait);
 871         return rc;
 872 }
 873
 874 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 875                       bool kern)
 876 {
 877         struct sock *sk = sock->sk;
 878         struct sock *newsk;
 879         struct sk_buff *skb;
 880         int rc = -EINVAL;
 881
 882         if (!sk)
 883                 goto out;
 884
 885         rc = -EOPNOTSUPP;
 886         if (sk->sk_type != SOCK_SEQPACKET)
 887                 goto out;
 888
 889         lock_sock(sk);
 890         rc = -EINVAL;
 891         if (sk->sk_state != TCP_LISTEN)
 892                 goto out2;
 893
 894         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 895         if (rc)
 896                 goto out2;
 897         skb = skb_dequeue(&sk->sk_receive_queue);
 898         rc = -EINVAL;
 899         if (!skb->sk)
 900                 goto out2;
 901         newsk            = skb->sk;
 902         sock_graft(newsk, newsock);
 903
 904         /* Now attach up the new socket */
 905         skb->sk = NULL;
 906         kfree_skb(skb);
 907         sk_acceptq_removed(sk);
 908         newsock->state = SS_CONNECTED;
 909         rc = 0;
 910 out2:
 911         release_sock(sk);
 912 out:
 913         return rc;
 914 }
 915
 916 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 917                        int peer)
 918 {
 919         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 920         struct sock *sk = sock->sk;
 921         struct x25_sock *x25 = x25_sk(sk);
 922         int rc = 0;
 923
 924         if (peer) {
 925                 if (sk->sk_state != TCP_ESTABLISHED) {
 926                         rc = -ENOTCONN;
 927                         goto out;
 928                 }
 929                 sx25->sx25_addr = x25->dest_addr;
 930         } else
 931                 sx25->sx25_addr = x25->source_addr;
 932
 933         sx25->sx25_family = AF_X25;
 934         rc = sizeof(*sx25);
 935
 936 out:
 937         return rc;
 938 }
 939
 940 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 941                         unsigned int lci)
 942 {
 943         struct sock *sk;
 944         struct sock *make;
 945         struct x25_sock *makex25;
 946         struct x25_address source_addr, dest_addr;
 947         struct x25_facilities facilities;
 948         struct x25_dte_facilities dte_facilities;
 949         int len, addr_len, rc;
 950
 951         /*
 952          *      Remove the LCI and frame type.
 953          */
 954         skb_pull(skb, X25_STD_MIN_LEN);
 955
 956         /*
 957          *      Extract the X.25 addresses and convert them to ASCII strings,
 958          *      and remove them.
 959          *
 960          *      Address block is mandatory in call request packets
 961          */
 962         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 963         if (addr_len <= 0)
 964                 goto out_clear_request;
 965         skb_pull(skb, addr_len);
 966
 967         /*
 968          *      Get the length of the facilities, skip past them for the moment
 969          *      get the call user data because this is needed to determine
 970          *      the correct listener
 971          *
 972          *      Facilities length is mandatory in call request packets
 973          */
 974         if (!pskb_may_pull(skb, 1))
 975                 goto out_clear_request;
 976         len = skb->data[0] + 1;
 977         if (!pskb_may_pull(skb, len))
 978                 goto out_clear_request;
 979         skb_pull(skb,len);
 980
 981         /*
 982          *      Ensure that the amount of call user data is valid.
 983          */
 984         if (skb->len > X25_MAX_CUD_LEN)
 985                 goto out_clear_request;
 986
 987         /*
 988          *      Get all the call user data so it can be used in
 989          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 990          */
 991         if (!pskb_may_pull(skb, skb->len))
 992                 goto out_clear_request;
 993
 994         /*
 995          *      Find a listener for the particular address/cud pair.
 996          */
 997         sk = x25_find_listener(&source_addr,skb);
 998         skb_push(skb,len);
 999
1000         if (sk != NULL && sk_acceptq_is_full(sk)) {
1001                 goto out_sock_put;
1002         }
1003
1004         /*
1005          *      We dont have any listeners for this incoming call.
1006          *      Try forwarding it.
1007          */
1008         if (sk == NULL) {
1009                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
1010                 if (sysctl_x25_forward &&
1011                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1012                 {
1013                         /* Call was forwarded, dont process it any more */
1014                         kfree_skb(skb);
1015                         rc = 1;
1016                         goto out;
1017                 } else {
1018                         /* No listeners, can't forward, clear the call */
1019                         goto out_clear_request;
1020                 }
1021         }
1022
1023         /*
1024          *      Try to reach a compromise on the requested facilities.
1025          */
1026         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1027         if (len == -1)
1028                 goto out_sock_put;
1029
1030         /*
1031          * current neighbour/link might impose additional limits
1032          * on certain facilities
1033          */
1034
1035         x25_limit_facilities(&facilities, nb);
1036
1037         /*
1038          *      Try to create a new socket.
1039          */
1040         make = x25_make_new(sk);
1041         if (!make)
1042                 goto out_sock_put;
1043
1044         /*
1045          *      Remove the facilities
1046          */
1047         skb_pull(skb, len);
1048
1049         skb->sk     = make;
1050         make->sk_state = TCP_ESTABLISHED;
1051
1052         makex25 = x25_sk(make);
1053         makex25->lci           = lci;
1054         makex25->dest_addr     = dest_addr;
1055         makex25->source_addr   = source_addr;
1056         x25_neigh_hold(nb);
1057         makex25->neighbour     = nb;
1058         makex25->facilities    = facilities;
1059         makex25->dte_facilities= dte_facilities;
1060         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1061         /* ensure no reverse facil on accept */
1062         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1063         /* ensure no calling address extension on accept */
1064         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1065         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1066
1067         /* Normally all calls are accepted immediately */
1068         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1069                 x25_write_internal(make, X25_CALL_ACCEPTED);
1070                 makex25->state = X25_STATE_3;
1071         } else {
1072                 makex25->state = X25_STATE_5;
1073         }
1074
1075         /*
1076          *      Incoming Call User Data.
1077          */
1078         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1079         makex25->calluserdata.cudlength = skb->len;
1080
1081         sk_acceptq_added(sk);
1082
1083         x25_insert_socket(make);
1084
1085         skb_queue_head(&sk->sk_receive_queue, skb);
1086
1087         x25_start_heartbeat(make);
1088
1089         if (!sock_flag(sk, SOCK_DEAD))
1090                 sk->sk_data_ready(sk);
1091         rc = 1;
1092         sock_put(sk);
1093 out:
1094         return rc;
1095 out_sock_put:
1096         sock_put(sk);
1097 out_clear_request:
1098         rc = 0;
1099         x25_transmit_clear_request(nb, lci, 0x01);
1100         goto out;
1101 }
1102
1103 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1104 {
1105         struct sock *sk = sock->sk;
1106         struct x25_sock *x25 = x25_sk(sk);
1107         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1108         struct sockaddr_x25 sx25;
1109         struct sk_buff *skb;
1110         unsigned char *asmptr;
1111         int noblock = msg->msg_flags & MSG_DONTWAIT;
1112         size_t size;
1113         int qbit = 0, rc = -EINVAL;
1114
1115         lock_sock(sk);
1116         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1117                 goto out;
1118
1119         /* we currently don't support segmented records at the user interface */
1120         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1121                 goto out;
1122
1123         rc = -EADDRNOTAVAIL;
1124         if (sock_flag(sk, SOCK_ZAPPED))
1125                 goto out;
1126
1127         rc = -EPIPE;
1128         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1129                 send_sig(SIGPIPE, current, 0);
1130                 goto out;
1131         }
1132
1133         rc = -ENETUNREACH;
1134         if (!x25->neighbour)
1135                 goto out;
1136
1137         if (usx25) {
1138                 rc = -EINVAL;
1139                 if (msg->msg_namelen < sizeof(sx25))
1140                         goto out;
1141                 memcpy(&sx25, usx25, sizeof(sx25));
1142                 rc = -EISCONN;
1143                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1144                         goto out;
1145                 rc = -EINVAL;
1146                 if (sx25.sx25_family != AF_X25)
1147                         goto out;
1148         } else {
1149                 /*
1150                  *      FIXME 1003.1g - if the socket is like this because
1151                  *      it has become closed (not started closed) we ought
1152                  *      to SIGPIPE, EPIPE;
1153                  */
1154                 rc = -ENOTCONN;
1155                 if (sk->sk_state != TCP_ESTABLISHED)
1156                         goto out;
1157
1158                 sx25.sx25_family = AF_X25;
1159                 sx25.sx25_addr   = x25->dest_addr;
1160         }
1161
1162         /* Sanity check the packet size */
1163         if (len > 65535) {
1164                 rc = -EMSGSIZE;
1165                 goto out;
1166         }
1167
1168         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1169
1170         /* Build a packet */
1171         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1172
1173         if ((msg->msg_flags & MSG_OOB) && len > 32)
1174                 len = 32;
1175
1176         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1177
1178         release_sock(sk);
1179         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1180         lock_sock(sk);
1181         if (!skb)
1182                 goto out;
1183         X25_SKB_CB(skb)->flags = msg->msg_flags;
1184
1185         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1186
1187         /*
1188          *      Put the data on the end
1189          */
1190         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1191
1192         skb_reset_transport_header(skb);
1193         skb_put(skb, len);
1194
1195         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1196         if (rc)
1197                 goto out_kfree_skb;
1198
1199         /*
1200          *      If the Q BIT Include socket option is in force, the first
1201          *      byte of the user data is the logical value of the Q Bit.
1202          */
1203         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1204                 if (!pskb_may_pull(skb, 1))
1205                         goto out_kfree_skb;
1206
1207                 qbit = skb->data[0];
1208                 skb_pull(skb, 1);
1209         }
1210
1211         /*
1212          *      Push down the X.25 header
1213          */
1214         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1215
1216         if (msg->msg_flags & MSG_OOB) {
1217                 if (x25->neighbour->extended) {
1218                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1219                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1220                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1221                         *asmptr++ = X25_INTERRUPT;
1222                 } else {
1223                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1224                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1225                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1226                         *asmptr++ = X25_INTERRUPT;
1227                 }
1228         } else {
1229                 if (x25->neighbour->extended) {
1230                         /* Build an Extended X.25 header */
1231                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1232                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1233                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1234                         *asmptr++ = X25_DATA;
1235                         *asmptr++ = X25_DATA;
1236                 } else {
1237                         /* Build an Standard X.25 header */
1238                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1239                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1240                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1241                         *asmptr++ = X25_DATA;
1242                 }
1243
1244                 if (qbit)
1245                         skb->data[0] |= X25_Q_BIT;
1246         }
1247
1248         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1249         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1250
1251         rc = -ENOTCONN;
1252         if (sk->sk_state != TCP_ESTABLISHED)
1253                 goto out_kfree_skb;
1254
1255         if (msg->msg_flags & MSG_OOB)
1256                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1257         else {
1258                 rc = x25_output(sk, skb);
1259                 len = rc;
1260                 if (rc < 0)
1261                         kfree_skb(skb);
1262                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1263                         len++;
1264         }
1265
1266         x25_kick(sk);
1267         rc = len;
1268 out:
1269         release_sock(sk);
1270         return rc;
1271 out_kfree_skb:
1272         kfree_skb(skb);
1273         goto out;
1274 }
1275
1276
1277 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1278                        int flags)
1279 {
1280         struct sock *sk = sock->sk;
1281         struct x25_sock *x25 = x25_sk(sk);
1282         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1283         size_t copied;
1284         int qbit, header_len;
1285         struct sk_buff *skb;
1286         unsigned char *asmptr;
1287         int rc = -ENOTCONN;
1288
1289         lock_sock(sk);
1290
1291         if (x25->neighbour == NULL)
1292                 goto out;
1293
1294         header_len = x25->neighbour->extended ?
1295                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1296
1297         /*
1298          * This works for seqpacket too. The receiver has ordered the queue for
1299          * us! We do one quick check first though
1300          */
1301         if (sk->sk_state != TCP_ESTABLISHED)
1302                 goto out;
1303
1304         if (flags & MSG_OOB) {
1305                 rc = -EINVAL;
1306                 if (sock_flag(sk, SOCK_URGINLINE) ||
1307                     !skb_peek(&x25->interrupt_in_queue))
1308                         goto out;
1309
1310                 skb = skb_dequeue(&x25->interrupt_in_queue);
1311
1312                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1313                         goto out_free_dgram;
1314
1315                 skb_pull(skb, X25_STD_MIN_LEN);
1316
1317                 /*
1318                  *      No Q bit information on Interrupt data.
1319                  */
1320                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1321                         asmptr  = skb_push(skb, 1);
1322                         *asmptr = 0x00;
1323                 }
1324
1325                 msg->msg_flags |= MSG_OOB;
1326         } else {
1327                 /* Now we can treat all alike */
1328                 release_sock(sk);
1329                 skb = skb_recv_datagram(sk, flags, &rc);
1330                 lock_sock(sk);
1331                 if (!skb)
1332                         goto out;
1333
1334                 if (!pskb_may_pull(skb, header_len))
1335                         goto out_free_dgram;
1336
1337                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1338
1339                 skb_pull(skb, header_len);
1340
1341                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1342                         asmptr  = skb_push(skb, 1);
1343                         *asmptr = qbit;
1344                 }
1345         }
1346
1347         skb_reset_transport_header(skb);
1348         copied = skb->len;
1349
1350         if (copied > size) {
1351                 copied = size;
1352                 msg->msg_flags |= MSG_TRUNC;
1353         }
1354
1355         /* Currently, each datagram always contains a complete record */
1356         msg->msg_flags |= MSG_EOR;
1357
1358         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1359         if (rc)
1360                 goto out_free_dgram;
1361
1362         if (sx25) {
1363                 sx25->sx25_family = AF_X25;
1364                 sx25->sx25_addr   = x25->dest_addr;
1365                 msg->msg_namelen = sizeof(*sx25);
1366         }
1367
1368         x25_check_rbuf(sk);
1369         rc = copied;
1370 out_free_dgram:
1371         skb_free_datagram(sk, skb);
1372 out:
1373         release_sock(sk);
1374         return rc;
1375 }
1376
1377
1378 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1379 {
1380         struct sock *sk = sock->sk;
1381         struct x25_sock *x25 = x25_sk(sk);
1382         void __user *argp = (void __user *)arg;
1383         int rc;
1384
1385         switch (cmd) {
1386         case TIOCOUTQ: {
1387                 int amount;
1388
1389                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1390                 if (amount < 0)
1391                         amount = 0;
1392                 rc = put_user(amount, (unsigned int __user *)argp);
1393                 break;
1394         }
1395
1396         case TIOCINQ: {
1397                 struct sk_buff *skb;
1398                 int amount = 0;
1399                 /*
1400                  * These two are safe on a single CPU system as
1401                  * only user tasks fiddle here
1402                  */
1403                 lock_sock(sk);
1404                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1405                         amount = skb->len;
1406                 release_sock(sk);
1407                 rc = put_user(amount, (unsigned int __user *)argp);
1408                 break;
1409         }
1410
1411         case SIOCGIFADDR:
1412         case SIOCSIFADDR:
1413         case SIOCGIFDSTADDR:
1414         case SIOCSIFDSTADDR:
1415         case SIOCGIFBRDADDR:
1416         case SIOCSIFBRDADDR:
1417         case SIOCGIFNETMASK:
1418         case SIOCSIFNETMASK:
1419         case SIOCGIFMETRIC:
1420         case SIOCSIFMETRIC:
1421                 rc = -EINVAL;
1422                 break;
1423         case SIOCADDRT:
1424         case SIOCDELRT:
1425                 rc = -EPERM;
1426                 if (!capable(CAP_NET_ADMIN))
1427                         break;
1428                 rc = x25_route_ioctl(cmd, argp);
1429                 break;
1430         case SIOCX25GSUBSCRIP:
1431                 rc = x25_subscr_ioctl(cmd, argp);
1432                 break;
1433         case SIOCX25SSUBSCRIP:
1434                 rc = -EPERM;
1435                 if (!capable(CAP_NET_ADMIN))
1436                         break;
1437                 rc = x25_subscr_ioctl(cmd, argp);
1438                 break;
1439         case SIOCX25GFACILITIES: {
1440                 lock_sock(sk);
1441                 rc = copy_to_user(argp, &x25->facilities,
1442                                   sizeof(x25->facilities))
1443                         ? -EFAULT : 0;
1444                 release_sock(sk);
1445                 break;
1446         }
1447
1448         case SIOCX25SFACILITIES: {
1449                 struct x25_facilities facilities;
1450                 rc = -EFAULT;
1451                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1452                         break;
1453                 rc = -EINVAL;
1454                 lock_sock(sk);
1455                 if (sk->sk_state != TCP_LISTEN &&
1456                     sk->sk_state != TCP_CLOSE)
1457                         goto out_fac_release;
1458                 if (facilities.pacsize_in < X25_PS16 ||
1459                     facilities.pacsize_in > X25_PS4096)
1460                         goto out_fac_release;
1461                 if (facilities.pacsize_out < X25_PS16 ||
1462                     facilities.pacsize_out > X25_PS4096)
1463                         goto out_fac_release;
1464                 if (facilities.winsize_in < 1 ||
1465                     facilities.winsize_in > 127)
1466                         goto out_fac_release;
1467                 if (facilities.throughput) {
1468                         int out = facilities.throughput & 0xf0;
1469                         int in  = facilities.throughput & 0x0f;
1470                         if (!out)
1471                                 facilities.throughput |=
1472                                         X25_DEFAULT_THROUGHPUT << 4;
1473                         else if (out < 0x30 || out > 0xD0)
1474                                 goto out_fac_release;
1475                         if (!in)
1476                                 facilities.throughput |=
1477                                         X25_DEFAULT_THROUGHPUT;
1478                         else if (in < 0x03 || in > 0x0D)
1479                                 goto out_fac_release;
1480                 }
1481                 if (facilities.reverse &&
1482                     (facilities.reverse & 0x81) != 0x81)
1483                         goto out_fac_release;
1484                 x25->facilities = facilities;
1485                 rc = 0;
1486 out_fac_release:
1487                 release_sock(sk);
1488                 break;
1489         }
1490
1491         case SIOCX25GDTEFACILITIES: {
1492                 lock_sock(sk);
1493                 rc = copy_to_user(argp, &x25->dte_facilities,
1494                                   sizeof(x25->dte_facilities));
1495                 release_sock(sk);
1496                 if (rc)
1497                         rc = -EFAULT;
1498                 break;
1499         }
1500
1501         case SIOCX25SDTEFACILITIES: {
1502                 struct x25_dte_facilities dtefacs;
1503                 rc = -EFAULT;
1504                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1505                         break;
1506                 rc = -EINVAL;
1507                 lock_sock(sk);
1508                 if (sk->sk_state != TCP_LISTEN &&
1509                     sk->sk_state != TCP_CLOSE)
1510                         goto out_dtefac_release;
1511                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1512                         goto out_dtefac_release;
1513                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1514                         goto out_dtefac_release;
1515                 x25->dte_facilities = dtefacs;
1516                 rc = 0;
1517 out_dtefac_release:
1518                 release_sock(sk);
1519                 break;
1520         }
1521
1522         case SIOCX25GCALLUSERDATA: {
1523                 lock_sock(sk);
1524                 rc = copy_to_user(argp, &x25->calluserdata,
1525                                   sizeof(x25->calluserdata))
1526                         ? -EFAULT : 0;
1527                 release_sock(sk);
1528                 break;
1529         }
1530
1531         case SIOCX25SCALLUSERDATA: {
1532                 struct x25_calluserdata calluserdata;
1533
1534                 rc = -EFAULT;
1535                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1536                         break;
1537                 rc = -EINVAL;
1538                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1539                         break;
1540                 lock_sock(sk);
1541                 x25->calluserdata = calluserdata;
1542                 release_sock(sk);
1543                 rc = 0;
1544                 break;
1545         }
1546
1547         case SIOCX25GCAUSEDIAG: {
1548                 lock_sock(sk);
1549                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1550                         ? -EFAULT : 0;
1551                 release_sock(sk);
1552                 break;
1553         }
1554
1555         case SIOCX25SCAUSEDIAG: {
1556                 struct x25_causediag causediag;
1557                 rc = -EFAULT;
1558                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1559                         break;
1560                 lock_sock(sk);
1561                 x25->causediag = causediag;
1562                 release_sock(sk);
1563                 rc = 0;
1564                 break;
1565
1566         }
1567
1568         case SIOCX25SCUDMATCHLEN: {
1569                 struct x25_subaddr sub_addr;
1570                 rc = -EINVAL;
1571                 lock_sock(sk);
1572                 if(sk->sk_state != TCP_CLOSE)
1573                         goto out_cud_release;
1574                 rc = -EFAULT;
1575                 if (copy_from_user(&sub_addr, argp,
1576                                    sizeof(sub_addr)))
1577                         goto out_cud_release;
1578                 rc = -EINVAL;
1579                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1580                         goto out_cud_release;
1581                 x25->cudmatchlength = sub_addr.cudmatchlength;
1582                 rc = 0;
1583 out_cud_release:
1584                 release_sock(sk);
1585                 break;
1586         }
1587
1588         case SIOCX25CALLACCPTAPPRV: {
1589                 rc = -EINVAL;
1590                 lock_sock(sk);
1591                 if (sk->sk_state == TCP_CLOSE) {
1592                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1593                         rc = 0;
1594                 }
1595                 release_sock(sk);
1596                 break;
1597         }
1598
1599         case SIOCX25SENDCALLACCPT:  {
1600                 rc = -EINVAL;
1601                 lock_sock(sk);
1602                 if (sk->sk_state != TCP_ESTABLISHED)
1603                         goto out_sendcallaccpt_release;
1604                 /* must call accptapprv above */
1605                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1606                         goto out_sendcallaccpt_release;
1607                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1608                 x25->state = X25_STATE_3;
1609                 rc = 0;
1610 out_sendcallaccpt_release:
1611                 release_sock(sk);
1612                 break;
1613         }
1614
1615         default:
1616                 rc = -ENOIOCTLCMD;
1617                 break;
1618         }
1619
1620         return rc;
1621 }
1622
1623 static const struct net_proto_family x25_family_ops = {
1624         .family =       AF_X25,
1625         .create =       x25_create,
1626         .owner  =       THIS_MODULE,
1627 };
1628
1629 #ifdef CONFIG_COMPAT
1630 static int compat_x25_subscr_ioctl(unsigned int cmd,
1631                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1632 {
1633         struct compat_x25_subscrip_struct x25_subscr;
1634         struct x25_neigh *nb;
1635         struct net_device *dev;
1636         int rc = -EINVAL;
1637
1638         rc = -EFAULT;
1639         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1640                 goto out;
1641
1642         rc = -EINVAL;
1643         dev = x25_dev_get(x25_subscr.device);
1644         if (dev == NULL)
1645                 goto out;
1646
1647         nb = x25_get_neigh(dev);
1648         if (nb == NULL)
1649                 goto out_dev_put;
1650
1651         dev_put(dev);
1652
1653         if (cmd == SIOCX25GSUBSCRIP) {
1654                 read_lock_bh(&x25_neigh_list_lock);
1655                 x25_subscr.extended = nb->extended;
1656                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1657                 read_unlock_bh(&x25_neigh_list_lock);
1658                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1659                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1660         } else {
1661                 rc = -EINVAL;
1662                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1663                         rc = 0;
1664                         write_lock_bh(&x25_neigh_list_lock);
1665                         nb->extended = x25_subscr.extended;
1666                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1667                         write_unlock_bh(&x25_neigh_list_lock);
1668                 }
1669         }
1670         x25_neigh_put(nb);
1671 out:
1672         return rc;
1673 out_dev_put:
1674         dev_put(dev);
1675         goto out;
1676 }
1677
1678 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1679                                 unsigned long arg)
1680 {
1681         void __user *argp = compat_ptr(arg);
1682         int rc = -ENOIOCTLCMD;
1683
1684         switch(cmd) {
1685         case TIOCOUTQ:
1686         case TIOCINQ:
1687                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1688                 break;
1689         case SIOCGIFADDR:
1690         case SIOCSIFADDR:
1691         case SIOCGIFDSTADDR:
1692         case SIOCSIFDSTADDR:
1693         case SIOCGIFBRDADDR:
1694         case SIOCSIFBRDADDR:
1695         case SIOCGIFNETMASK:
1696         case SIOCSIFNETMASK:
1697         case SIOCGIFMETRIC:
1698         case SIOCSIFMETRIC:
1699                 rc = -EINVAL;
1700                 break;
1701         case SIOCADDRT:
1702         case SIOCDELRT:
1703                 rc = -EPERM;
1704                 if (!capable(CAP_NET_ADMIN))
1705                         break;
1706                 rc = x25_route_ioctl(cmd, argp);
1707                 break;
1708         case SIOCX25GSUBSCRIP:
1709                 rc = compat_x25_subscr_ioctl(cmd, argp);
1710                 break;
1711         case SIOCX25SSUBSCRIP:
1712                 rc = -EPERM;
1713                 if (!capable(CAP_NET_ADMIN))
1714                         break;
1715                 rc = compat_x25_subscr_ioctl(cmd, argp);
1716                 break;
1717         case SIOCX25GFACILITIES:
1718         case SIOCX25SFACILITIES:
1719         case SIOCX25GDTEFACILITIES:
1720         case SIOCX25SDTEFACILITIES:
1721         case SIOCX25GCALLUSERDATA:
1722         case SIOCX25SCALLUSERDATA:
1723         case SIOCX25GCAUSEDIAG:
1724         case SIOCX25SCAUSEDIAG:
1725         case SIOCX25SCUDMATCHLEN:
1726         case SIOCX25CALLACCPTAPPRV:
1727         case SIOCX25SENDCALLACCPT:
1728                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1729                 break;
1730         default:
1731                 rc = -ENOIOCTLCMD;
1732                 break;
1733         }
1734         return rc;
1735 }
1736 #endif
1737
1738 static const struct proto_ops x25_proto_ops = {
1739         .family =       AF_X25,
1740         .owner =        THIS_MODULE,
1741         .release =      x25_release,
1742         .bind =         x25_bind,
1743         .connect =      x25_connect,
1744         .socketpair =   sock_no_socketpair,
1745         .accept =       x25_accept,
1746         .getname =      x25_getname,
1747         .poll =         datagram_poll,
1748         .ioctl =        x25_ioctl,
1749 #ifdef CONFIG_COMPAT
1750         .compat_ioctl = compat_x25_ioctl,
1751 #endif
1752         .gettstamp =    sock_gettstamp,
1753         .listen =       x25_listen,
1754         .shutdown =     sock_no_shutdown,
1755         .setsockopt =   x25_setsockopt,
1756         .getsockopt =   x25_getsockopt,
1757         .sendmsg =      x25_sendmsg,
1758         .recvmsg =      x25_recvmsg,
1759         .mmap =         sock_no_mmap,
1760         .sendpage =     sock_no_sendpage,
1761 };
1762
1763 static struct packet_type x25_packet_type __read_mostly = {
1764         .type = cpu_to_be16(ETH_P_X25),
1765         .func = x25_lapb_receive_frame,
1766 };
1767
1768 static struct notifier_block x25_dev_notifier = {
1769         .notifier_call = x25_device_event,
1770 };
1771
1772 void x25_kill_by_neigh(struct x25_neigh *nb)
1773 {
1774         struct sock *s;
1775
1776         write_lock_bh(&x25_list_lock);
1777
1778         sk_for_each(s, &x25_list) {
1779                 if (x25_sk(s)->neighbour == nb) {
1780                         write_unlock_bh(&x25_list_lock);
1781                         lock_sock(s);
1782                         x25_disconnect(s, ENETUNREACH, 0, 0);
1783                         release_sock(s);
1784                         write_lock_bh(&x25_list_lock);
1785                 }
1786         }
1787         write_unlock_bh(&x25_list_lock);
1788
1789         /* Remove any related forwards */
1790         x25_clear_forward_by_dev(nb->dev);
1791 }
1792
1793 static int __init x25_init(void)
1794 {
1795         int rc;
1796
1797         rc = proto_register(&x25_proto, 0);
1798         if (rc)
1799                 goto out;
1800
1801         rc = sock_register(&x25_family_ops);
1802         if (rc)
1803                 goto out_proto;
1804
1805         dev_add_pack(&x25_packet_type);
1806
1807         rc = register_netdevice_notifier(&x25_dev_notifier);
1808         if (rc)
1809                 goto out_sock;
1810
1811         rc = x25_register_sysctl();
1812         if (rc)
1813                 goto out_dev;
1814
1815         rc = x25_proc_init();
1816         if (rc)
1817                 goto out_sysctl;
1818
1819         pr_info("Linux Version 0.2\n");
1820
1821 out:
1822         return rc;
1823 out_sysctl:
1824         x25_unregister_sysctl();
1825 out_dev:
1826         unregister_netdevice_notifier(&x25_dev_notifier);
1827 out_sock:
1828         dev_remove_pack(&x25_packet_type);
1829         sock_unregister(AF_X25);
1830 out_proto:
1831         proto_unregister(&x25_proto);
1832         goto out;
1833 }
1834 module_init(x25_init);
1835
1836 static void __exit x25_exit(void)
1837 {
1838         x25_proc_exit();
1839         x25_link_free();
1840         x25_route_free();
1841
1842         x25_unregister_sysctl();
1843
1844         unregister_netdevice_notifier(&x25_dev_notifier);
1845
1846         dev_remove_pack(&x25_packet_type);
1847
1848         sock_unregister(AF_X25);
1849         proto_unregister(&x25_proto);
1850 }
1851 module_exit(x25_exit);
1852
1853 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1854 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1855 MODULE_LICENSE("GPL");
1856 MODULE_ALIAS_NETPROTO(PF_X25);