net/rose/rose_route.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *
   4  * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
   5  * Copyright (C) Terry Dawson VK2KTJ (terry@animats.net)
   6  */
   7 #include <linux/errno.h>
   8 #include <linux/types.h>
   9 #include <linux/socket.h>
  10 #include <linux/in.h>
  11 #include <linux/kernel.h>
  12 #include <linux/timer.h>
  13 #include <linux/string.h>
  14 #include <linux/sockios.h>
  15 #include <linux/net.h>
  16 #include <linux/slab.h>
  17 #include <net/ax25.h>
  18 #include <linux/inet.h>
  19 #include <linux/netdevice.h>
  20 #include <net/arp.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/skbuff.h>
  23 #include <net/sock.h>
  24 #include <net/tcp_states.h>
  25 #include <linux/uaccess.h>
  26 #include <linux/fcntl.h>
  27 #include <linux/termios.h>      /* For TIOCINQ/OUTQ */
  28 #include <linux/mm.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/notifier.h>
  31 #include <linux/init.h>
  32 #include <net/rose.h>
  33 #include <linux/seq_file.h>
  34 #include <linux/export.h>
  35
  36 static unsigned int rose_neigh_no = 1;
  37
  38 static struct rose_node  *rose_node_list;
  39 static DEFINE_SPINLOCK(rose_node_list_lock);
  40 static struct rose_neigh *rose_neigh_list;
  41 static DEFINE_SPINLOCK(rose_neigh_list_lock);
  42 static struct rose_route *rose_route_list;
  43 static DEFINE_SPINLOCK(rose_route_list_lock);
  44
  45 struct rose_neigh *rose_loopback_neigh;
  46
  47 /*
  48  *      Add a new route to a node, and in the process add the node and the
  49  *      neighbour if it is new.
  50  */
  51 static int __must_check rose_add_node(struct rose_route_struct *rose_route,
  52         struct net_device *dev)
  53 {
  54         struct rose_node  *rose_node, *rose_tmpn, *rose_tmpp;
  55         struct rose_neigh *rose_neigh;
  56         int i, res = 0;
  57
  58         spin_lock_bh(&rose_node_list_lock);
  59         spin_lock_bh(&rose_neigh_list_lock);
  60
  61         rose_node = rose_node_list;
  62         while (rose_node != NULL) {
  63                 if ((rose_node->mask == rose_route->mask) &&
  64                     (rosecmpm(&rose_route->address, &rose_node->address,
  65                               rose_route->mask) == 0))
  66                         break;
  67                 rose_node = rose_node->next;
  68         }
  69
  70         if (rose_node != NULL && rose_node->loopback) {
  71                 res = -EINVAL;
  72                 goto out;
  73         }
  74
  75         rose_neigh = rose_neigh_list;
  76         while (rose_neigh != NULL) {
  77                 if (ax25cmp(&rose_route->neighbour,
  78                             &rose_neigh->callsign) == 0 &&
  79                     rose_neigh->dev == dev)
  80                         break;
  81                 rose_neigh = rose_neigh->next;
  82         }
  83
  84         if (rose_neigh == NULL) {
  85                 rose_neigh = kmalloc(sizeof(*rose_neigh), GFP_ATOMIC);
  86                 if (rose_neigh == NULL) {
  87                         res = -ENOMEM;
  88                         goto out;
  89                 }
  90
  91                 rose_neigh->callsign  = rose_route->neighbour;
  92                 rose_neigh->digipeat  = NULL;
  93                 rose_neigh->ax25      = NULL;
  94                 rose_neigh->dev       = dev;
  95                 rose_neigh->count     = 0;
  96                 rose_neigh->use       = 0;
  97                 rose_neigh->dce_mode  = 0;
  98                 rose_neigh->loopback  = 0;
  99                 rose_neigh->number    = rose_neigh_no++;
 100                 rose_neigh->restarted = 0;
 101
 102                 skb_queue_head_init(&rose_neigh->queue);
 103
 104                 timer_setup(&rose_neigh->ftimer, NULL, 0);
 105                 timer_setup(&rose_neigh->t0timer, NULL, 0);
 106
 107                 if (rose_route->ndigis != 0) {
 108                         rose_neigh->digipeat =
 109                                 kmalloc(sizeof(ax25_digi), GFP_ATOMIC);
 110                         if (rose_neigh->digipeat == NULL) {
 111                                 kfree(rose_neigh);
 112                                 res = -ENOMEM;
 113                                 goto out;
 114                         }
 115
 116                         rose_neigh->digipeat->ndigi      = rose_route->ndigis;
 117                         rose_neigh->digipeat->lastrepeat = -1;
 118
 119                         for (i = 0; i < rose_route->ndigis; i++) {
 120                                 rose_neigh->digipeat->calls[i]    =
 121                                         rose_route->digipeaters[i];
 122                                 rose_neigh->digipeat->repeated[i] = 0;
 123                         }
 124                 }
 125
 126                 rose_neigh->next = rose_neigh_list;
 127                 rose_neigh_list  = rose_neigh;
 128         }
 129
 130         /*
 131          * This is a new node to be inserted into the list. Find where it needs
 132          * to be inserted into the list, and insert it. We want to be sure
 133          * to order the list in descending order of mask size to ensure that
 134          * later when we are searching this list the first match will be the
 135          * best match.
 136          */
 137         if (rose_node == NULL) {
 138                 rose_tmpn = rose_node_list;
 139                 rose_tmpp = NULL;
 140
 141                 while (rose_tmpn != NULL) {
 142                         if (rose_tmpn->mask > rose_route->mask) {
 143                                 rose_tmpp = rose_tmpn;
 144                                 rose_tmpn = rose_tmpn->next;
 145                         } else {
 146                                 break;
 147                         }
 148                 }
 149
 150                 /* create new node */
 151                 rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC);
 152                 if (rose_node == NULL) {
 153                         res = -ENOMEM;
 154                         goto out;
 155                 }
 156
 157                 rose_node->address      = rose_route->address;
 158                 rose_node->mask         = rose_route->mask;
 159                 rose_node->count        = 1;
 160                 rose_node->loopback     = 0;
 161                 rose_node->neighbour[0] = rose_neigh;
 162
 163                 if (rose_tmpn == NULL) {
 164                         if (rose_tmpp == NULL) {        /* Empty list */
 165                                 rose_node_list  = rose_node;
 166                                 rose_node->next = NULL;
 167                         } else {
 168                                 rose_tmpp->next = rose_node;
 169                                 rose_node->next = NULL;
 170                         }
 171                 } else {
 172                         if (rose_tmpp == NULL) {        /* 1st node */
 173                                 rose_node->next = rose_node_list;
 174                                 rose_node_list  = rose_node;
 175                         } else {
 176                                 rose_tmpp->next = rose_node;
 177                                 rose_node->next = rose_tmpn;
 178                         }
 179                 }
 180                 rose_neigh->count++;
 181
 182                 goto out;
 183         }
 184
 185         /* We have space, slot it in */
 186         if (rose_node->count < 3) {
 187                 rose_node->neighbour[rose_node->count] = rose_neigh;
 188                 rose_node->count++;
 189                 rose_neigh->count++;
 190         }
 191
 192 out:
 193         spin_unlock_bh(&rose_neigh_list_lock);
 194         spin_unlock_bh(&rose_node_list_lock);
 195
 196         return res;
 197 }
 198
 199 /*
 200  * Caller is holding rose_node_list_lock.
 201  */
 202 static void rose_remove_node(struct rose_node *rose_node)
 203 {
 204         struct rose_node *s;
 205
 206         if ((s = rose_node_list) == rose_node) {
 207                 rose_node_list = rose_node->next;
 208                 kfree(rose_node);
 209                 return;
 210         }
 211
 212         while (s != NULL && s->next != NULL) {
 213                 if (s->next == rose_node) {
 214                         s->next = rose_node->next;
 215                         kfree(rose_node);
 216                         return;
 217                 }
 218
 219                 s = s->next;
 220         }
 221 }
 222
 223 /*
 224  * Caller is holding rose_neigh_list_lock.
 225  */
 226 static void rose_remove_neigh(struct rose_neigh *rose_neigh)
 227 {
 228         struct rose_neigh *s;
 229
 230         del_timer_sync(&rose_neigh->ftimer);
 231         del_timer_sync(&rose_neigh->t0timer);
 232
 233         skb_queue_purge(&rose_neigh->queue);
 234
 235         if ((s = rose_neigh_list) == rose_neigh) {
 236                 rose_neigh_list = rose_neigh->next;
 237                 if (rose_neigh->ax25)
 238                         ax25_cb_put(rose_neigh->ax25);
 239                 kfree(rose_neigh->digipeat);
 240                 kfree(rose_neigh);
 241                 return;
 242         }
 243
 244         while (s != NULL && s->next != NULL) {
 245                 if (s->next == rose_neigh) {
 246                         s->next = rose_neigh->next;
 247                         if (rose_neigh->ax25)
 248                                 ax25_cb_put(rose_neigh->ax25);
 249                         kfree(rose_neigh->digipeat);
 250                         kfree(rose_neigh);
 251                         return;
 252                 }
 253
 254                 s = s->next;
 255         }
 256 }
 257
 258 /*
 259  * Caller is holding rose_route_list_lock.
 260  */
 261 static void rose_remove_route(struct rose_route *rose_route)
 262 {
 263         struct rose_route *s;
 264
 265         if (rose_route->neigh1 != NULL)
 266                 rose_route->neigh1->use--;
 267
 268         if (rose_route->neigh2 != NULL)
 269                 rose_route->neigh2->use--;
 270
 271         if ((s = rose_route_list) == rose_route) {
 272                 rose_route_list = rose_route->next;
 273                 kfree(rose_route);
 274                 return;
 275         }
 276
 277         while (s != NULL && s->next != NULL) {
 278                 if (s->next == rose_route) {
 279                         s->next = rose_route->next;
 280                         kfree(rose_route);
 281                         return;
 282                 }
 283
 284                 s = s->next;
 285         }
 286 }
 287
 288 /*
 289  *      "Delete" a node. Strictly speaking remove a route to a node. The node
 290  *      is only deleted if no routes are left to it.
 291  */
 292 static int rose_del_node(struct rose_route_struct *rose_route,
 293         struct net_device *dev)
 294 {
 295         struct rose_node  *rose_node;
 296         struct rose_neigh *rose_neigh;
 297         int i, err = 0;
 298
 299         spin_lock_bh(&rose_node_list_lock);
 300         spin_lock_bh(&rose_neigh_list_lock);
 301
 302         rose_node = rose_node_list;
 303         while (rose_node != NULL) {
 304                 if ((rose_node->mask == rose_route->mask) &&
 305                     (rosecmpm(&rose_route->address, &rose_node->address,
 306                               rose_route->mask) == 0))
 307                         break;
 308                 rose_node = rose_node->next;
 309         }
 310
 311         if (rose_node == NULL || rose_node->loopback) {
 312                 err = -EINVAL;
 313                 goto out;
 314         }
 315
 316         rose_neigh = rose_neigh_list;
 317         while (rose_neigh != NULL) {
 318                 if (ax25cmp(&rose_route->neighbour,
 319                             &rose_neigh->callsign) == 0 &&
 320                     rose_neigh->dev == dev)
 321                         break;
 322                 rose_neigh = rose_neigh->next;
 323         }
 324
 325         if (rose_neigh == NULL) {
 326                 err = -EINVAL;
 327                 goto out;
 328         }
 329
 330         for (i = 0; i < rose_node->count; i++) {
 331                 if (rose_node->neighbour[i] == rose_neigh) {
 332                         rose_neigh->count--;
 333
 334                         if (rose_neigh->count == 0 && rose_neigh->use == 0)
 335                                 rose_remove_neigh(rose_neigh);
 336
 337                         rose_node->count--;
 338
 339                         if (rose_node->count == 0) {
 340                                 rose_remove_node(rose_node);
 341                         } else {
 342                                 switch (i) {
 343                                 case 0:
 344                                         rose_node->neighbour[0] =
 345                                                 rose_node->neighbour[1];
 346                                         fallthrough;
 347                                 case 1:
 348                                         rose_node->neighbour[1] =
 349                                                 rose_node->neighbour[2];
 350                                         break;
 351                                 case 2:
 352                                         break;
 353                                 }
 354                         }
 355                         goto out;
 356                 }
 357         }
 358         err = -EINVAL;
 359
 360 out:
 361         spin_unlock_bh(&rose_neigh_list_lock);
 362         spin_unlock_bh(&rose_node_list_lock);
 363
 364         return err;
 365 }
 366
 367 /*
 368  *      Add the loopback neighbour.
 369  */
 370 void rose_add_loopback_neigh(void)
 371 {
 372         struct rose_neigh *sn;
 373
 374         rose_loopback_neigh = kmalloc(sizeof(struct rose_neigh), GFP_KERNEL);
 375         if (!rose_loopback_neigh)
 376                 return;
 377         sn = rose_loopback_neigh;
 378
 379         sn->callsign  = null_ax25_address;
 380         sn->digipeat  = NULL;
 381         sn->ax25      = NULL;
 382         sn->dev       = NULL;
 383         sn->count     = 0;
 384         sn->use       = 0;
 385         sn->dce_mode  = 1;
 386         sn->loopback  = 1;
 387         sn->number    = rose_neigh_no++;
 388         sn->restarted = 1;
 389
 390         skb_queue_head_init(&sn->queue);
 391
 392         timer_setup(&sn->ftimer, NULL, 0);
 393         timer_setup(&sn->t0timer, NULL, 0);
 394
 395         spin_lock_bh(&rose_neigh_list_lock);
 396         sn->next = rose_neigh_list;
 397         rose_neigh_list           = sn;
 398         spin_unlock_bh(&rose_neigh_list_lock);
 399 }
 400
 401 /*
 402  *      Add a loopback node.
 403  */
 404 int rose_add_loopback_node(const rose_address *address)
 405 {
 406         struct rose_node *rose_node;
 407         int err = 0;
 408
 409         spin_lock_bh(&rose_node_list_lock);
 410
 411         rose_node = rose_node_list;
 412         while (rose_node != NULL) {
 413                 if ((rose_node->mask == 10) &&
 414                      (rosecmpm(address, &rose_node->address, 10) == 0) &&
 415                      rose_node->loopback)
 416                         break;
 417                 rose_node = rose_node->next;
 418         }
 419
 420         if (rose_node != NULL)
 421                 goto out;
 422
 423         if ((rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC)) == NULL) {
 424                 err = -ENOMEM;
 425                 goto out;
 426         }
 427
 428         rose_node->address      = *address;
 429         rose_node->mask         = 10;
 430         rose_node->count        = 1;
 431         rose_node->loopback     = 1;
 432         rose_node->neighbour[0] = rose_loopback_neigh;
 433
 434         /* Insert at the head of list. Address is always mask=10 */
 435         rose_node->next = rose_node_list;
 436         rose_node_list  = rose_node;
 437
 438         rose_loopback_neigh->count++;
 439
 440 out:
 441         spin_unlock_bh(&rose_node_list_lock);
 442
 443         return err;
 444 }
 445
 446 /*
 447  *      Delete a loopback node.
 448  */
 449 void rose_del_loopback_node(const rose_address *address)
 450 {
 451         struct rose_node *rose_node;
 452
 453         spin_lock_bh(&rose_node_list_lock);
 454
 455         rose_node = rose_node_list;
 456         while (rose_node != NULL) {
 457                 if ((rose_node->mask == 10) &&
 458                     (rosecmpm(address, &rose_node->address, 10) == 0) &&
 459                     rose_node->loopback)
 460                         break;
 461                 rose_node = rose_node->next;
 462         }
 463
 464         if (rose_node == NULL)
 465                 goto out;
 466
 467         rose_remove_node(rose_node);
 468
 469         rose_loopback_neigh->count--;
 470
 471 out:
 472         spin_unlock_bh(&rose_node_list_lock);
 473 }
 474
 475 /*
 476  *      A device has been removed. Remove its routes and neighbours.
 477  */
 478 void rose_rt_device_down(struct net_device *dev)
 479 {
 480         struct rose_neigh *s, *rose_neigh;
 481         struct rose_node  *t, *rose_node;
 482         int i;
 483
 484         spin_lock_bh(&rose_node_list_lock);
 485         spin_lock_bh(&rose_neigh_list_lock);
 486         rose_neigh = rose_neigh_list;
 487         while (rose_neigh != NULL) {
 488                 s          = rose_neigh;
 489                 rose_neigh = rose_neigh->next;
 490
 491                 if (s->dev != dev)
 492                         continue;
 493
 494                 rose_node = rose_node_list;
 495
 496                 while (rose_node != NULL) {
 497                         t         = rose_node;
 498                         rose_node = rose_node->next;
 499
 500                         for (i = 0; i < t->count; i++) {
 501                                 if (t->neighbour[i] != s)
 502                                         continue;
 503
 504                                 t->count--;
 505
 506                                 switch (i) {
 507                                 case 0:
 508                                         t->neighbour[0] = t->neighbour[1];
 509                                         fallthrough;
 510                                 case 1:
 511                                         t->neighbour[1] = t->neighbour[2];
 512                                         break;
 513                                 case 2:
 514                                         break;
 515                                 }
 516                         }
 517
 518                         if (t->count <= 0)
 519                                 rose_remove_node(t);
 520                 }
 521
 522                 rose_remove_neigh(s);
 523         }
 524         spin_unlock_bh(&rose_neigh_list_lock);
 525         spin_unlock_bh(&rose_node_list_lock);
 526 }
 527
 528 #if 0 /* Currently unused */
 529 /*
 530  *      A device has been removed. Remove its links.
 531  */
 532 void rose_route_device_down(struct net_device *dev)
 533 {
 534         struct rose_route *s, *rose_route;
 535
 536         spin_lock_bh(&rose_route_list_lock);
 537         rose_route = rose_route_list;
 538         while (rose_route != NULL) {
 539                 s          = rose_route;
 540                 rose_route = rose_route->next;
 541
 542                 if (s->neigh1->dev == dev || s->neigh2->dev == dev)
 543                         rose_remove_route(s);
 544         }
 545         spin_unlock_bh(&rose_route_list_lock);
 546 }
 547 #endif
 548
 549 /*
 550  *      Clear all nodes and neighbours out, except for neighbours with
 551  *      active connections going through them.
 552  *  Do not clear loopback neighbour and nodes.
 553  */
 554 static int rose_clear_routes(void)
 555 {
 556         struct rose_neigh *s, *rose_neigh;
 557         struct rose_node  *t, *rose_node;
 558
 559         spin_lock_bh(&rose_node_list_lock);
 560         spin_lock_bh(&rose_neigh_list_lock);
 561
 562         rose_neigh = rose_neigh_list;
 563         rose_node  = rose_node_list;
 564
 565         while (rose_node != NULL) {
 566                 t         = rose_node;
 567                 rose_node = rose_node->next;
 568                 if (!t->loopback)
 569                         rose_remove_node(t);
 570         }
 571
 572         while (rose_neigh != NULL) {
 573                 s          = rose_neigh;
 574                 rose_neigh = rose_neigh->next;
 575
 576                 if (s->use == 0 && !s->loopback) {
 577                         s->count = 0;
 578                         rose_remove_neigh(s);
 579                 }
 580         }
 581
 582         spin_unlock_bh(&rose_neigh_list_lock);
 583         spin_unlock_bh(&rose_node_list_lock);
 584
 585         return 0;
 586 }
 587
 588 /*
 589  *      Check that the device given is a valid AX.25 interface that is "up".
 590  *      called with RTNL
 591  */
 592 static struct net_device *rose_ax25_dev_find(char *devname)
 593 {
 594         struct net_device *dev;
 595
 596         if ((dev = __dev_get_by_name(&init_net, devname)) == NULL)
 597                 return NULL;
 598
 599         if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
 600                 return dev;
 601
 602         return NULL;
 603 }
 604
 605 /*
 606  *      Find the first active ROSE device, usually "rose0".
 607  */
 608 struct net_device *rose_dev_first(void)
 609 {
 610         struct net_device *dev, *first = NULL;
 611
 612         rcu_read_lock();
 613         for_each_netdev_rcu(&init_net, dev) {
 614                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE)
 615                         if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
 616                                 first = dev;
 617         }
 618         rcu_read_unlock();
 619
 620         return first;
 621 }
 622
 623 /*
 624  *      Find the ROSE device for the given address.
 625  */
 626 struct net_device *rose_dev_get(rose_address *addr)
 627 {
 628         struct net_device *dev;
 629
 630         rcu_read_lock();
 631         for_each_netdev_rcu(&init_net, dev) {
 632                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
 633                     rosecmp(addr, (const rose_address *)dev->dev_addr) == 0) {
 634                         dev_hold(dev);
 635                         goto out;
 636                 }
 637         }
 638         dev = NULL;
 639 out:
 640         rcu_read_unlock();
 641         return dev;
 642 }
 643
 644 static int rose_dev_exists(rose_address *addr)
 645 {
 646         struct net_device *dev;
 647
 648         rcu_read_lock();
 649         for_each_netdev_rcu(&init_net, dev) {
 650                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
 651                     rosecmp(addr, (const rose_address *)dev->dev_addr) == 0)
 652                         goto out;
 653         }
 654         dev = NULL;
 655 out:
 656         rcu_read_unlock();
 657         return dev != NULL;
 658 }
 659
 660
 661
 662
 663 struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
 664 {
 665         struct rose_route *rose_route;
 666
 667         for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
 668                 if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
 669                     (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
 670                         return rose_route;
 671
 672         return NULL;
 673 }
 674
 675 /*
 676  *      Find a neighbour or a route given a ROSE address.
 677  */
 678 struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
 679         unsigned char *diagnostic, int route_frame)
 680 {
 681         struct rose_neigh *res = NULL;
 682         struct rose_node *node;
 683         int failed = 0;
 684         int i;
 685
 686         if (!route_frame) spin_lock_bh(&rose_node_list_lock);
 687         for (node = rose_node_list; node != NULL; node = node->next) {
 688                 if (rosecmpm(addr, &node->address, node->mask) == 0) {
 689                         for (i = 0; i < node->count; i++) {
 690                                 if (node->neighbour[i]->restarted) {
 691                                         res = node->neighbour[i];
 692                                         goto out;
 693                                 }
 694                         }
 695                 }
 696         }
 697         if (!route_frame) { /* connect request */
 698                 for (node = rose_node_list; node != NULL; node = node->next) {
 699                         if (rosecmpm(addr, &node->address, node->mask) == 0) {
 700                                 for (i = 0; i < node->count; i++) {
 701                                         if (!rose_ftimer_running(node->neighbour[i])) {
 702                                                 res = node->neighbour[i];
 703                                                 goto out;
 704                                         }
 705                                         failed = 1;
 706                                 }
 707                         }
 708                 }
 709         }
 710
 711         if (failed) {
 712                 *cause      = ROSE_OUT_OF_ORDER;
 713                 *diagnostic = 0;
 714         } else {
 715                 *cause      = ROSE_NOT_OBTAINABLE;
 716                 *diagnostic = 0;
 717         }
 718
 719 out:
 720         if (!route_frame) spin_unlock_bh(&rose_node_list_lock);
 721         return res;
 722 }
 723
 724 /*
 725  *      Handle the ioctls that control the routing functions.
 726  */
 727 int rose_rt_ioctl(unsigned int cmd, void __user *arg)
 728 {
 729         struct rose_route_struct rose_route;
 730         struct net_device *dev;
 731         int err;
 732
 733         switch (cmd) {
 734         case SIOCADDRT:
 735                 if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
 736                         return -EFAULT;
 737                 if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
 738                         return -EINVAL;
 739                 if (rose_dev_exists(&rose_route.address)) /* Can't add routes to ourself */
 740                         return -EINVAL;
 741                 if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
 742                         return -EINVAL;
 743                 if (rose_route.ndigis > AX25_MAX_DIGIS)
 744                         return -EINVAL;
 745                 err = rose_add_node(&rose_route, dev);
 746                 return err;
 747
 748         case SIOCDELRT:
 749                 if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
 750                         return -EFAULT;
 751                 if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
 752                         return -EINVAL;
 753                 err = rose_del_node(&rose_route, dev);
 754                 return err;
 755
 756         case SIOCRSCLRRT:
 757                 return rose_clear_routes();
 758
 759         default:
 760                 return -EINVAL;
 761         }
 762
 763         return 0;
 764 }
 765
 766 static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
 767 {
 768         struct rose_route *rose_route, *s;
 769
 770         rose_neigh->restarted = 0;
 771
 772         rose_stop_t0timer(rose_neigh);
 773         rose_start_ftimer(rose_neigh);
 774
 775         skb_queue_purge(&rose_neigh->queue);
 776
 777         spin_lock_bh(&rose_route_list_lock);
 778
 779         rose_route = rose_route_list;
 780
 781         while (rose_route != NULL) {
 782                 if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
 783                     (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
 784                     (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
 785                         s = rose_route->next;
 786                         rose_remove_route(rose_route);
 787                         rose_route = s;
 788                         continue;
 789                 }
 790
 791                 if (rose_route->neigh1 == rose_neigh) {
 792                         rose_route->neigh1->use--;
 793                         rose_route->neigh1 = NULL;
 794                         rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
 795                 }
 796
 797                 if (rose_route->neigh2 == rose_neigh) {
 798                         rose_route->neigh2->use--;
 799                         rose_route->neigh2 = NULL;
 800                         rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
 801                 }
 802
 803                 rose_route = rose_route->next;
 804         }
 805         spin_unlock_bh(&rose_route_list_lock);
 806 }
 807
 808 /*
 809  *      A level 2 link has timed out, therefore it appears to be a poor link,
 810  *      then don't use that neighbour until it is reset. Blow away all through
 811  *      routes and connections using this route.
 812  */
 813 void rose_link_failed(ax25_cb *ax25, int reason)
 814 {
 815         struct rose_neigh *rose_neigh;
 816
 817         spin_lock_bh(&rose_neigh_list_lock);
 818         rose_neigh = rose_neigh_list;
 819         while (rose_neigh != NULL) {
 820                 if (rose_neigh->ax25 == ax25)
 821                         break;
 822                 rose_neigh = rose_neigh->next;
 823         }
 824
 825         if (rose_neigh != NULL) {
 826                 rose_neigh->ax25 = NULL;
 827                 ax25_cb_put(ax25);
 828
 829                 rose_del_route_by_neigh(rose_neigh);
 830                 rose_kill_by_neigh(rose_neigh);
 831         }
 832         spin_unlock_bh(&rose_neigh_list_lock);
 833 }
 834
 835 /*
 836  *      A device has been "downed" remove its link status. Blow away all
 837  *      through routes and connections that use this device.
 838  */
 839 void rose_link_device_down(struct net_device *dev)
 840 {
 841         struct rose_neigh *rose_neigh;
 842
 843         for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
 844                 if (rose_neigh->dev == dev) {
 845                         rose_del_route_by_neigh(rose_neigh);
 846                         rose_kill_by_neigh(rose_neigh);
 847                 }
 848         }
 849 }
 850
 851 /*
 852  *      Route a frame to an appropriate AX.25 connection.
 853  *      A NULL ax25_cb indicates an internally generated frame.
 854  */
 855 int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
 856 {
 857         struct rose_neigh *rose_neigh, *new_neigh;
 858         struct rose_route *rose_route;
 859         struct rose_facilities_struct facilities;
 860         rose_address *src_addr, *dest_addr;
 861         struct sock *sk;
 862         unsigned short frametype;
 863         unsigned int lci, new_lci;
 864         unsigned char cause, diagnostic;
 865         struct net_device *dev;
 866         int res = 0;
 867         char buf[11];
 868
 869         if (skb->len < ROSE_MIN_LEN)
 870                 return res;
 871
 872         if (!ax25)
 873                 return rose_loopback_queue(skb, NULL);
 874
 875         frametype = skb->data[2];
 876         lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
 877         if (frametype == ROSE_CALL_REQUEST &&
 878             (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF ||
 879              skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] !=
 880              ROSE_CALL_REQ_ADDR_LEN_VAL))
 881                 return res;
 882         src_addr  = (rose_address *)(skb->data + ROSE_CALL_REQ_SRC_ADDR_OFF);
 883         dest_addr = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF);
 884
 885         spin_lock_bh(&rose_neigh_list_lock);
 886         spin_lock_bh(&rose_route_list_lock);
 887
 888         rose_neigh = rose_neigh_list;
 889         while (rose_neigh != NULL) {
 890                 if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
 891                     ax25->ax25_dev->dev == rose_neigh->dev)
 892                         break;
 893                 rose_neigh = rose_neigh->next;
 894         }
 895
 896         if (rose_neigh == NULL) {
 897                 printk("rose_route : unknown neighbour or device %s\n",
 898                        ax2asc(buf, &ax25->dest_addr));
 899                 goto out;
 900         }
 901
 902         /*
 903          *      Obviously the link is working, halt the ftimer.
 904          */
 905         rose_stop_ftimer(rose_neigh);
 906
 907         /*
 908          *      LCI of zero is always for us, and its always a restart
 909          *      frame.
 910          */
 911         if (lci == 0) {
 912                 rose_link_rx_restart(skb, rose_neigh, frametype);
 913                 goto out;
 914         }
 915
 916         /*
 917          *      Find an existing socket.
 918          */
 919         if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
 920                 if (frametype == ROSE_CALL_REQUEST) {
 921                         struct rose_sock *rose = rose_sk(sk);
 922
 923                         /* Remove an existing unused socket */
 924                         rose_clear_queues(sk);
 925                         rose->cause      = ROSE_NETWORK_CONGESTION;
 926                         rose->diagnostic = 0;
 927                         rose->neighbour->use--;
 928                         rose->neighbour  = NULL;
 929                         rose->lci        = 0;
 930                         rose->state      = ROSE_STATE_0;
 931                         sk->sk_state     = TCP_CLOSE;
 932                         sk->sk_err       = 0;
 933                         sk->sk_shutdown  |= SEND_SHUTDOWN;
 934                         if (!sock_flag(sk, SOCK_DEAD)) {
 935                                 sk->sk_state_change(sk);
 936                                 sock_set_flag(sk, SOCK_DEAD);
 937                         }
 938                 }
 939                 else {
 940                         skb_reset_transport_header(skb);
 941                         res = rose_process_rx_frame(sk, skb);
 942                         goto out;
 943                 }
 944         }
 945
 946         /*
 947          *      Is is a Call Request and is it for us ?
 948          */
 949         if (frametype == ROSE_CALL_REQUEST)
 950                 if ((dev = rose_dev_get(dest_addr)) != NULL) {
 951                         res = rose_rx_call_request(skb, dev, rose_neigh, lci);
 952                         dev_put(dev);
 953                         goto out;
 954                 }
 955
 956         if (!sysctl_rose_routing_control) {
 957                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
 958                 goto out;
 959         }
 960
 961         /*
 962          *      Route it to the next in line if we have an entry for it.
 963          */
 964         rose_route = rose_route_list;
 965         while (rose_route != NULL) {
 966                 if (rose_route->lci1 == lci &&
 967                     rose_route->neigh1 == rose_neigh) {
 968                         if (frametype == ROSE_CALL_REQUEST) {
 969                                 /* F6FBB - Remove an existing unused route */
 970                                 rose_remove_route(rose_route);
 971                                 break;
 972                         } else if (rose_route->neigh2 != NULL) {
 973                                 skb->data[0] &= 0xF0;
 974                                 skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
 975                                 skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
 976                                 rose_transmit_link(skb, rose_route->neigh2);
 977                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
 978                                         rose_remove_route(rose_route);
 979                                 res = 1;
 980                                 goto out;
 981                         } else {
 982                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
 983                                         rose_remove_route(rose_route);
 984                                 goto out;
 985                         }
 986                 }
 987                 if (rose_route->lci2 == lci &&
 988                     rose_route->neigh2 == rose_neigh) {
 989                         if (frametype == ROSE_CALL_REQUEST) {
 990                                 /* F6FBB - Remove an existing unused route */
 991                                 rose_remove_route(rose_route);
 992                                 break;
 993                         } else if (rose_route->neigh1 != NULL) {
 994                                 skb->data[0] &= 0xF0;
 995                                 skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
 996                                 skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
 997                                 rose_transmit_link(skb, rose_route->neigh1);
 998                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
 999                                         rose_remove_route(rose_route);
1000                                 res = 1;
1001                                 goto out;
1002                         } else {
1003                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
1004                                         rose_remove_route(rose_route);
1005                                 goto out;
1006                         }
1007                 }
1008                 rose_route = rose_route->next;
1009         }
1010
1011         /*
1012          *      We know that:
1013          *      1. The frame isn't for us,
1014          *      2. It isn't "owned" by any existing route.
1015          */
1016         if (frametype != ROSE_CALL_REQUEST) {   /* XXX */
1017                 res = 0;
1018                 goto out;
1019         }
1020
1021         memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
1022
1023         if (!rose_parse_facilities(skb->data + ROSE_CALL_REQ_FACILITIES_OFF,
1024                                    skb->len - ROSE_CALL_REQ_FACILITIES_OFF,
1025                                    &facilities)) {
1026                 rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
1027                 goto out;
1028         }
1029
1030         /*
1031          *      Check for routing loops.
1032          */
1033         rose_route = rose_route_list;
1034         while (rose_route != NULL) {
1035                 if (rose_route->rand == facilities.rand &&
1036                     rosecmp(src_addr, &rose_route->src_addr) == 0 &&
1037                     ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
1038                     ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
1039                         rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
1040                         goto out;
1041                 }
1042                 rose_route = rose_route->next;
1043         }
1044
1045         if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
1046                 rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
1047                 goto out;
1048         }
1049
1050         if ((new_lci = rose_new_lci(new_neigh)) == 0) {
1051                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
1052                 goto out;
1053         }
1054
1055         if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
1056                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
1057                 goto out;
1058         }
1059
1060         rose_route->lci1      = lci;
1061         rose_route->src_addr  = *src_addr;
1062         rose_route->dest_addr = *dest_addr;
1063         rose_route->src_call  = facilities.dest_call;
1064         rose_route->dest_call = facilities.source_call;
1065         rose_route->rand      = facilities.rand;
1066         rose_route->neigh1    = rose_neigh;
1067         rose_route->lci2      = new_lci;
1068         rose_route->neigh2    = new_neigh;
1069
1070         rose_route->neigh1->use++;
1071         rose_route->neigh2->use++;
1072
1073         rose_route->next = rose_route_list;
1074         rose_route_list  = rose_route;
1075
1076         skb->data[0] &= 0xF0;
1077         skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
1078         skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
1079
1080         rose_transmit_link(skb, rose_route->neigh2);
1081         res = 1;
1082
1083 out:
1084         spin_unlock_bh(&rose_route_list_lock);
1085         spin_unlock_bh(&rose_neigh_list_lock);
1086
1087         return res;
1088 }
1089
1090 #ifdef CONFIG_PROC_FS
1091
1092 static void *rose_node_start(struct seq_file *seq, loff_t *pos)
1093         __acquires(rose_node_list_lock)
1094 {
1095         struct rose_node *rose_node;
1096         int i = 1;
1097
1098         spin_lock_bh(&rose_node_list_lock);
1099         if (*pos == 0)
1100                 return SEQ_START_TOKEN;
1101
1102         for (rose_node = rose_node_list; rose_node && i < *pos;
1103              rose_node = rose_node->next, ++i);
1104
1105         return (i == *pos) ? rose_node : NULL;
1106 }
1107
1108 static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
1109 {
1110         ++*pos;
1111
1112         return (v == SEQ_START_TOKEN) ? rose_node_list
1113                 : ((struct rose_node *)v)->next;
1114 }
1115
1116 static void rose_node_stop(struct seq_file *seq, void *v)
1117         __releases(rose_node_list_lock)
1118 {
1119         spin_unlock_bh(&rose_node_list_lock);
1120 }
1121
1122 static int rose_node_show(struct seq_file *seq, void *v)
1123 {
1124         char rsbuf[11];
1125         int i;
1126
1127         if (v == SEQ_START_TOKEN)
1128                 seq_puts(seq, "address    mask n neigh neigh neigh\n");
1129         else {
1130                 const struct rose_node *rose_node = v;
1131                 seq_printf(seq, "%-10s %04d %d",
1132                            rose2asc(rsbuf, &rose_node->address),
1133                            rose_node->mask,
1134                            rose_node->count);
1135
1136                 for (i = 0; i < rose_node->count; i++)
1137                         seq_printf(seq, " %05d", rose_node->neighbour[i]->number);
1138
1139                 seq_puts(seq, "\n");
1140         }
1141         return 0;
1142 }
1143
1144 const struct seq_operations rose_node_seqops = {
1145         .start = rose_node_start,
1146         .next = rose_node_next,
1147         .stop = rose_node_stop,
1148         .show = rose_node_show,
1149 };
1150
1151 static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
1152         __acquires(rose_neigh_list_lock)
1153 {
1154         struct rose_neigh *rose_neigh;
1155         int i = 1;
1156
1157         spin_lock_bh(&rose_neigh_list_lock);
1158         if (*pos == 0)
1159                 return SEQ_START_TOKEN;
1160
1161         for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
1162              rose_neigh = rose_neigh->next, ++i);
1163
1164         return (i == *pos) ? rose_neigh : NULL;
1165 }
1166
1167 static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
1168 {
1169         ++*pos;
1170
1171         return (v == SEQ_START_TOKEN) ? rose_neigh_list
1172                 : ((struct rose_neigh *)v)->next;
1173 }
1174
1175 static void rose_neigh_stop(struct seq_file *seq, void *v)
1176         __releases(rose_neigh_list_lock)
1177 {
1178         spin_unlock_bh(&rose_neigh_list_lock);
1179 }
1180
1181 static int rose_neigh_show(struct seq_file *seq, void *v)
1182 {
1183         char buf[11];
1184         int i;
1185
1186         if (v == SEQ_START_TOKEN)
1187                 seq_puts(seq,
1188                          "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
1189         else {
1190                 struct rose_neigh *rose_neigh = v;
1191
1192                 /* if (!rose_neigh->loopback) { */
1193                 seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
1194                            rose_neigh->number,
1195                            (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
1196                            rose_neigh->dev ? rose_neigh->dev->name : "???",
1197                            rose_neigh->count,
1198                            rose_neigh->use,
1199                            (rose_neigh->dce_mode) ? "DCE" : "DTE",
1200                            (rose_neigh->restarted) ? "yes" : "no",
1201                            ax25_display_timer(&rose_neigh->t0timer) / HZ,
1202                            ax25_display_timer(&rose_neigh->ftimer)  / HZ);
1203
1204                 if (rose_neigh->digipeat != NULL) {
1205                         for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
1206                                 seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
1207                 }
1208
1209                 seq_puts(seq, "\n");
1210         }
1211         return 0;
1212 }
1213
1214
1215 const struct seq_operations rose_neigh_seqops = {
1216         .start = rose_neigh_start,
1217         .next = rose_neigh_next,
1218         .stop = rose_neigh_stop,
1219         .show = rose_neigh_show,
1220 };
1221
1222 static void *rose_route_start(struct seq_file *seq, loff_t *pos)
1223         __acquires(rose_route_list_lock)
1224 {
1225         struct rose_route *rose_route;
1226         int i = 1;
1227
1228         spin_lock_bh(&rose_route_list_lock);
1229         if (*pos == 0)
1230                 return SEQ_START_TOKEN;
1231
1232         for (rose_route = rose_route_list; rose_route && i < *pos;
1233              rose_route = rose_route->next, ++i);
1234
1235         return (i == *pos) ? rose_route : NULL;
1236 }
1237
1238 static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
1239 {
1240         ++*pos;
1241
1242         return (v == SEQ_START_TOKEN) ? rose_route_list
1243                 : ((struct rose_route *)v)->next;
1244 }
1245
1246 static void rose_route_stop(struct seq_file *seq, void *v)
1247         __releases(rose_route_list_lock)
1248 {
1249         spin_unlock_bh(&rose_route_list_lock);
1250 }
1251
1252 static int rose_route_show(struct seq_file *seq, void *v)
1253 {
1254         char buf[11], rsbuf[11];
1255
1256         if (v == SEQ_START_TOKEN)
1257                 seq_puts(seq,
1258                          "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
1259         else {
1260                 struct rose_route *rose_route = v;
1261
1262                 if (rose_route->neigh1)
1263                         seq_printf(seq,
1264                                    "%3.3X  %-10s  %-9s  %05d      ",
1265                                    rose_route->lci1,
1266                                    rose2asc(rsbuf, &rose_route->src_addr),
1267                                    ax2asc(buf, &rose_route->src_call),
1268                                    rose_route->neigh1->number);
1269                 else
1270                         seq_puts(seq,
1271                                  "000  *           *          00000      ");
1272
1273                 if (rose_route->neigh2)
1274                         seq_printf(seq,
1275                                    "%3.3X  %-10s  %-9s  %05d\n",
1276                                    rose_route->lci2,
1277                                    rose2asc(rsbuf, &rose_route->dest_addr),
1278                                    ax2asc(buf, &rose_route->dest_call),
1279                                    rose_route->neigh2->number);
1280                  else
1281                          seq_puts(seq,
1282                                   "000  *           *          00000\n");
1283                 }
1284         return 0;
1285 }
1286
1287 struct seq_operations rose_route_seqops = {
1288         .start = rose_route_start,
1289         .next = rose_route_next,
1290         .stop = rose_route_stop,
1291         .show = rose_route_show,
1292 };
1293 #endif /* CONFIG_PROC_FS */
1294
1295 /*
1296  *      Release all memory associated with ROSE routing structures.
1297  */
1298 void __exit rose_rt_free(void)
1299 {
1300         struct rose_neigh *s, *rose_neigh = rose_neigh_list;
1301         struct rose_node  *t, *rose_node  = rose_node_list;
1302         struct rose_route *u, *rose_route = rose_route_list;
1303
1304         while (rose_neigh != NULL) {
1305                 s          = rose_neigh;
1306                 rose_neigh = rose_neigh->next;
1307
1308                 rose_remove_neigh(s);
1309         }
1310
1311         while (rose_node != NULL) {
1312                 t         = rose_node;
1313                 rose_node = rose_node->next;
1314
1315                 rose_remove_node(t);
1316         }
1317
1318         while (rose_route != NULL) {
1319                 u          = rose_route;
1320                 rose_route = rose_route->next;
1321
1322                 rose_remove_route(u);
1323         }
1324 }