net/netrom/nr_route.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License as published by
   4  * the Free Software Foundation; either version 2 of the License, or
   5  * (at your option) any later version.
   6  *
   7  * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
   8  * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
   9  * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
  10  */
  11 #include <linux/errno.h>
  12 #include <linux/types.h>
  13 #include <linux/socket.h>
  14 #include <linux/in.h>
  15 #include <linux/kernel.h>
  16 #include <linux/timer.h>
  17 #include <linux/string.h>
  18 #include <linux/sockios.h>
  19 #include <linux/net.h>
  20 #include <linux/slab.h>
  21 #include <net/ax25.h>
  22 #include <linux/inet.h>
  23 #include <linux/netdevice.h>
  24 #include <net/arp.h>
  25 #include <linux/if_arp.h>
  26 #include <linux/skbuff.h>
  27 #include <net/sock.h>
  28 #include <asm/uaccess.h>
  29 #include <asm/system.h>
  30 #include <linux/fcntl.h>
  31 #include <linux/termios.h>      /* For TIOCINQ/OUTQ */
  32 #include <linux/mm.h>
  33 #include <linux/interrupt.h>
  34 #include <linux/notifier.h>
  35 #include <linux/netfilter.h>
  36 #include <linux/init.h>
  37 #include <linux/spinlock.h>
  38 #include <net/netrom.h>
  39 #include <linux/seq_file.h>
  40
  41 static unsigned int nr_neigh_no = 1;
  42
  43 static HLIST_HEAD(nr_node_list);
  44 static DEFINE_SPINLOCK(nr_node_list_lock);
  45 static HLIST_HEAD(nr_neigh_list);
  46 static DEFINE_SPINLOCK(nr_neigh_list_lock);
  47
  48 static struct nr_node *nr_node_get(ax25_address *callsign)
  49 {
  50         struct nr_node *found = NULL;
  51         struct nr_node *nr_node;
  52         struct hlist_node *node;
  53
  54         spin_lock_bh(&nr_node_list_lock);
  55         nr_node_for_each(nr_node, node, &nr_node_list)
  56                 if (ax25cmp(callsign, &nr_node->callsign) == 0) {
  57                         nr_node_hold(nr_node);
  58                         found = nr_node;
  59                         break;
  60                 }
  61         spin_unlock_bh(&nr_node_list_lock);
  62         return found;
  63 }
  64
  65 static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
  66                                          struct net_device *dev)
  67 {
  68         struct nr_neigh *found = NULL;
  69         struct nr_neigh *nr_neigh;
  70         struct hlist_node *node;
  71
  72         spin_lock_bh(&nr_neigh_list_lock);
  73         nr_neigh_for_each(nr_neigh, node, &nr_neigh_list)
  74                 if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
  75                     nr_neigh->dev == dev) {
  76                         nr_neigh_hold(nr_neigh);
  77                         found = nr_neigh;
  78                         break;
  79                 }
  80         spin_unlock_bh(&nr_neigh_list_lock);
  81         return found;
  82 }
  83
  84 static void nr_remove_neigh(struct nr_neigh *);
  85
  86 /*
  87  *      Add a new route to a node, and in the process add the node and the
  88  *      neighbour if it is new.
  89  */
  90 static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
  91         ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
  92         int quality, int obs_count)
  93 {
  94         struct nr_node  *nr_node;
  95         struct nr_neigh *nr_neigh;
  96         struct nr_route nr_route;
  97         int i, found;
  98         struct net_device *odev;
  99
 100         if ((odev=nr_dev_get(nr)) != NULL) {    /* Can't add routes to ourself */
 101                 dev_put(odev);
 102                 return -EINVAL;
 103         }
 104
 105         nr_node = nr_node_get(nr);
 106
 107         nr_neigh = nr_neigh_get_dev(ax25, dev);
 108
 109         /*
 110          * The L2 link to a neighbour has failed in the past
 111          * and now a frame comes from this neighbour. We assume
 112          * it was a temporary trouble with the link and reset the
 113          * routes now (and not wait for a node broadcast).
 114          */
 115         if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
 116                 struct nr_node *nr_nodet;
 117                 struct hlist_node *node;
 118
 119                 spin_lock_bh(&nr_node_list_lock);
 120                 nr_node_for_each(nr_nodet, node, &nr_node_list) {
 121                         nr_node_lock(nr_nodet);
 122                         for (i = 0; i < nr_nodet->count; i++)
 123                                 if (nr_nodet->routes[i].neighbour == nr_neigh)
 124                                         if (i < nr_nodet->which)
 125                                                 nr_nodet->which = i;
 126                         nr_node_unlock(nr_nodet);
 127                 }
 128                 spin_unlock_bh(&nr_node_list_lock);
 129         }
 130
 131         if (nr_neigh != NULL)
 132                 nr_neigh->failed = 0;
 133
 134         if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
 135                 nr_neigh_put(nr_neigh);
 136                 nr_node_put(nr_node);
 137                 return 0;
 138         }
 139
 140         if (nr_neigh == NULL) {
 141                 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
 142                         if (nr_node)
 143                                 nr_node_put(nr_node);
 144                         return -ENOMEM;
 145                 }
 146
 147                 nr_neigh->callsign = *ax25;
 148                 nr_neigh->digipeat = NULL;
 149                 nr_neigh->ax25     = NULL;
 150                 nr_neigh->dev      = dev;
 151                 nr_neigh->quality  = sysctl_netrom_default_path_quality;
 152                 nr_neigh->locked   = 0;
 153                 nr_neigh->count    = 0;
 154                 nr_neigh->number   = nr_neigh_no++;
 155                 nr_neigh->failed   = 0;
 156                 atomic_set(&nr_neigh->refcount, 1);
 157
 158                 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
 159                         nr_neigh->digipeat = kmemdup(ax25_digi,
 160                                                      sizeof(*ax25_digi),
 161                                                      GFP_KERNEL);
 162                         if (nr_neigh->digipeat == NULL) {
 163                                 kfree(nr_neigh);
 164                                 if (nr_node)
 165                                         nr_node_put(nr_node);
 166                                 return -ENOMEM;
 167                         }
 168                 }
 169
 170                 spin_lock_bh(&nr_neigh_list_lock);
 171                 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
 172                 nr_neigh_hold(nr_neigh);
 173                 spin_unlock_bh(&nr_neigh_list_lock);
 174         }
 175
 176         if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
 177                 nr_neigh->quality = quality;
 178
 179         if (nr_node == NULL) {
 180                 if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
 181                         if (nr_neigh)
 182                                 nr_neigh_put(nr_neigh);
 183                         return -ENOMEM;
 184                 }
 185
 186                 nr_node->callsign = *nr;
 187                 strcpy(nr_node->mnemonic, mnemonic);
 188
 189                 nr_node->which = 0;
 190                 nr_node->count = 1;
 191                 atomic_set(&nr_node->refcount, 1);
 192                 spin_lock_init(&nr_node->node_lock);
 193
 194                 nr_node->routes[0].quality   = quality;
 195                 nr_node->routes[0].obs_count = obs_count;
 196                 nr_node->routes[0].neighbour = nr_neigh;
 197
 198                 nr_neigh_hold(nr_neigh);
 199                 nr_neigh->count++;
 200
 201                 spin_lock_bh(&nr_node_list_lock);
 202                 hlist_add_head(&nr_node->node_node, &nr_node_list);
 203                 /* refcount initialized at 1 */
 204                 spin_unlock_bh(&nr_node_list_lock);
 205
 206                 return 0;
 207         }
 208         nr_node_lock(nr_node);
 209
 210         if (quality != 0)
 211                 strcpy(nr_node->mnemonic, mnemonic);
 212
 213         for (found = 0, i = 0; i < nr_node->count; i++) {
 214                 if (nr_node->routes[i].neighbour == nr_neigh) {
 215                         nr_node->routes[i].quality   = quality;
 216                         nr_node->routes[i].obs_count = obs_count;
 217                         found = 1;
 218                         break;
 219                 }
 220         }
 221
 222         if (!found) {
 223                 /* We have space at the bottom, slot it in */
 224                 if (nr_node->count < 3) {
 225                         nr_node->routes[2] = nr_node->routes[1];
 226                         nr_node->routes[1] = nr_node->routes[0];
 227
 228                         nr_node->routes[0].quality   = quality;
 229                         nr_node->routes[0].obs_count = obs_count;
 230                         nr_node->routes[0].neighbour = nr_neigh;
 231
 232                         nr_node->which++;
 233                         nr_node->count++;
 234                         nr_neigh_hold(nr_neigh);
 235                         nr_neigh->count++;
 236                 } else {
 237                         /* It must be better than the worst */
 238                         if (quality > nr_node->routes[2].quality) {
 239                                 nr_node->routes[2].neighbour->count--;
 240                                 nr_neigh_put(nr_node->routes[2].neighbour);
 241
 242                                 if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
 243                                         nr_remove_neigh(nr_node->routes[2].neighbour);
 244
 245                                 nr_node->routes[2].quality   = quality;
 246                                 nr_node->routes[2].obs_count = obs_count;
 247                                 nr_node->routes[2].neighbour = nr_neigh;
 248
 249                                 nr_neigh_hold(nr_neigh);
 250                                 nr_neigh->count++;
 251                         }
 252                 }
 253         }
 254
 255         /* Now re-sort the routes in quality order */
 256         switch (nr_node->count) {
 257         case 3:
 258                 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
 259                         switch (nr_node->which) {
 260                         case 0:
 261                                 nr_node->which = 1;
 262                                 break;
 263                         case 1:
 264                                 nr_node->which = 0;
 265                                 break;
 266                         }
 267                         nr_route           = nr_node->routes[0];
 268                         nr_node->routes[0] = nr_node->routes[1];
 269                         nr_node->routes[1] = nr_route;
 270                 }
 271                 if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
 272                         switch (nr_node->which) {
 273                         case 1:  nr_node->which = 2;
 274                                 break;
 275
 276                         case 2:  nr_node->which = 1;
 277                                 break;
 278
 279                         default:
 280                                 break;
 281                         }
 282                         nr_route           = nr_node->routes[1];
 283                         nr_node->routes[1] = nr_node->routes[2];
 284                         nr_node->routes[2] = nr_route;
 285                 }
 286         case 2:
 287                 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
 288                         switch (nr_node->which) {
 289                         case 0:  nr_node->which = 1;
 290                                 break;
 291
 292                         case 1:  nr_node->which = 0;
 293                                 break;
 294
 295                         default: break;
 296                         }
 297                         nr_route           = nr_node->routes[0];
 298                         nr_node->routes[0] = nr_node->routes[1];
 299                         nr_node->routes[1] = nr_route;
 300                         }
 301         case 1:
 302                 break;
 303         }
 304
 305         for (i = 0; i < nr_node->count; i++) {
 306                 if (nr_node->routes[i].neighbour == nr_neigh) {
 307                         if (i < nr_node->which)
 308                                 nr_node->which = i;
 309                         break;
 310                 }
 311         }
 312
 313         nr_neigh_put(nr_neigh);
 314         nr_node_unlock(nr_node);
 315         nr_node_put(nr_node);
 316         return 0;
 317 }
 318
 319 static inline void __nr_remove_node(struct nr_node *nr_node)
 320 {
 321         hlist_del_init(&nr_node->node_node);
 322         nr_node_put(nr_node);
 323 }
 324
 325 #define nr_remove_node_locked(__node) \
 326         __nr_remove_node(__node)
 327
 328 static void nr_remove_node(struct nr_node *nr_node)
 329 {
 330         spin_lock_bh(&nr_node_list_lock);
 331         __nr_remove_node(nr_node);
 332         spin_unlock_bh(&nr_node_list_lock);
 333 }
 334
 335 static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
 336 {
 337         hlist_del_init(&nr_neigh->neigh_node);
 338         nr_neigh_put(nr_neigh);
 339 }
 340
 341 #define nr_remove_neigh_locked(__neigh) \
 342         __nr_remove_neigh(__neigh)
 343
 344 static void nr_remove_neigh(struct nr_neigh *nr_neigh)
 345 {
 346         spin_lock_bh(&nr_neigh_list_lock);
 347         __nr_remove_neigh(nr_neigh);
 348         spin_unlock_bh(&nr_neigh_list_lock);
 349 }
 350
 351 /*
 352  *      "Delete" a node. Strictly speaking remove a route to a node. The node
 353  *      is only deleted if no routes are left to it.
 354  */
 355 static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
 356 {
 357         struct nr_node  *nr_node;
 358         struct nr_neigh *nr_neigh;
 359         int i;
 360
 361         nr_node = nr_node_get(callsign);
 362
 363         if (nr_node == NULL)
 364                 return -EINVAL;
 365
 366         nr_neigh = nr_neigh_get_dev(neighbour, dev);
 367
 368         if (nr_neigh == NULL) {
 369                 nr_node_put(nr_node);
 370                 return -EINVAL;
 371         }
 372
 373         nr_node_lock(nr_node);
 374         for (i = 0; i < nr_node->count; i++) {
 375                 if (nr_node->routes[i].neighbour == nr_neigh) {
 376                         nr_neigh->count--;
 377                         nr_neigh_put(nr_neigh);
 378
 379                         if (nr_neigh->count == 0 && !nr_neigh->locked)
 380                                 nr_remove_neigh(nr_neigh);
 381                         nr_neigh_put(nr_neigh);
 382
 383                         nr_node->count--;
 384
 385                         if (nr_node->count == 0) {
 386                                 nr_remove_node(nr_node);
 387                         } else {
 388                                 switch (i) {
 389                                 case 0:
 390                                         nr_node->routes[0] = nr_node->routes[1];
 391                                 case 1:
 392                                         nr_node->routes[1] = nr_node->routes[2];
 393                                 case 2:
 394                                         break;
 395                                 }
 396                                 nr_node_put(nr_node);
 397                         }
 398                         nr_node_unlock(nr_node);
 399
 400                         return 0;
 401                 }
 402         }
 403         nr_neigh_put(nr_neigh);
 404         nr_node_unlock(nr_node);
 405         nr_node_put(nr_node);
 406
 407         return -EINVAL;
 408 }
 409
 410 /*
 411  *      Lock a neighbour with a quality.
 412  */
 413 static int __must_check nr_add_neigh(ax25_address *callsign,
 414         ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
 415 {
 416         struct nr_neigh *nr_neigh;
 417
 418         nr_neigh = nr_neigh_get_dev(callsign, dev);
 419         if (nr_neigh) {
 420                 nr_neigh->quality = quality;
 421                 nr_neigh->locked  = 1;
 422                 nr_neigh_put(nr_neigh);
 423                 return 0;
 424         }
 425
 426         if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
 427                 return -ENOMEM;
 428
 429         nr_neigh->callsign = *callsign;
 430         nr_neigh->digipeat = NULL;
 431         nr_neigh->ax25     = NULL;
 432         nr_neigh->dev      = dev;
 433         nr_neigh->quality  = quality;
 434         nr_neigh->locked   = 1;
 435         nr_neigh->count    = 0;
 436         nr_neigh->number   = nr_neigh_no++;
 437         nr_neigh->failed   = 0;
 438         atomic_set(&nr_neigh->refcount, 1);
 439
 440         if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
 441                 nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
 442                                              GFP_KERNEL);
 443                 if (nr_neigh->digipeat == NULL) {
 444                         kfree(nr_neigh);
 445                         return -ENOMEM;
 446                 }
 447         }
 448
 449         spin_lock_bh(&nr_neigh_list_lock);
 450         hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
 451         /* refcount is initialized at 1 */
 452         spin_unlock_bh(&nr_neigh_list_lock);
 453
 454         return 0;
 455 }
 456
 457 /*
 458  *      "Delete" a neighbour. The neighbour is only removed if the number
 459  *      of nodes that may use it is zero.
 460  */
 461 static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
 462 {
 463         struct nr_neigh *nr_neigh;
 464
 465         nr_neigh = nr_neigh_get_dev(callsign, dev);
 466
 467         if (nr_neigh == NULL) return -EINVAL;
 468
 469         nr_neigh->quality = quality;
 470         nr_neigh->locked  = 0;
 471
 472         if (nr_neigh->count == 0)
 473                 nr_remove_neigh(nr_neigh);
 474         nr_neigh_put(nr_neigh);
 475
 476         return 0;
 477 }
 478
 479 /*
 480  *      Decrement the obsolescence count by one. If a route is reduced to a
 481  *      count of zero, remove it. Also remove any unlocked neighbours with
 482  *      zero nodes routing via it.
 483  */
 484 static int nr_dec_obs(void)
 485 {
 486         struct nr_neigh *nr_neigh;
 487         struct nr_node  *s;
 488         struct hlist_node *node, *nodet;
 489         int i;
 490
 491         spin_lock_bh(&nr_node_list_lock);
 492         nr_node_for_each_safe(s, node, nodet, &nr_node_list) {
 493                 nr_node_lock(s);
 494                 for (i = 0; i < s->count; i++) {
 495                         switch (s->routes[i].obs_count) {
 496                         case 0:         /* A locked entry */
 497                                 break;
 498
 499                         case 1:         /* From 1 -> 0 */
 500                                 nr_neigh = s->routes[i].neighbour;
 501
 502                                 nr_neigh->count--;
 503                                 nr_neigh_put(nr_neigh);
 504
 505                                 if (nr_neigh->count == 0 && !nr_neigh->locked)
 506                                         nr_remove_neigh(nr_neigh);
 507
 508                                 s->count--;
 509
 510                                 switch (i) {
 511                                 case 0:
 512                                         s->routes[0] = s->routes[1];
 513                                         /* Fallthrough */
 514                                 case 1:
 515                                         s->routes[1] = s->routes[2];
 516                                 case 2:
 517                                         break;
 518                                 }
 519                                 break;
 520
 521                         default:
 522                                 s->routes[i].obs_count--;
 523                                 break;
 524
 525                         }
 526                 }
 527
 528                 if (s->count <= 0)
 529                         nr_remove_node_locked(s);
 530                 nr_node_unlock(s);
 531         }
 532         spin_unlock_bh(&nr_node_list_lock);
 533
 534         return 0;
 535 }
 536
 537 /*
 538  *      A device has been removed. Remove its routes and neighbours.
 539  */
 540 void nr_rt_device_down(struct net_device *dev)
 541 {
 542         struct nr_neigh *s;
 543         struct hlist_node *node, *nodet, *node2, *node2t;
 544         struct nr_node  *t;
 545         int i;
 546
 547         spin_lock_bh(&nr_neigh_list_lock);
 548         nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
 549                 if (s->dev == dev) {
 550                         spin_lock_bh(&nr_node_list_lock);
 551                         nr_node_for_each_safe(t, node2, node2t, &nr_node_list) {
 552                                 nr_node_lock(t);
 553                                 for (i = 0; i < t->count; i++) {
 554                                         if (t->routes[i].neighbour == s) {
 555                                                 t->count--;
 556
 557                                                 switch (i) {
 558                                                 case 0:
 559                                                         t->routes[0] = t->routes[1];
 560                                                 case 1:
 561                                                         t->routes[1] = t->routes[2];
 562                                                 case 2:
 563                                                         break;
 564                                                 }
 565                                         }
 566                                 }
 567
 568                                 if (t->count <= 0)
 569                                         nr_remove_node_locked(t);
 570                                 nr_node_unlock(t);
 571                         }
 572                         spin_unlock_bh(&nr_node_list_lock);
 573
 574                         nr_remove_neigh_locked(s);
 575                 }
 576         }
 577         spin_unlock_bh(&nr_neigh_list_lock);
 578 }
 579
 580 /*
 581  *      Check that the device given is a valid AX.25 interface that is "up".
 582  *      Or a valid ethernet interface with an AX.25 callsign binding.
 583  */
 584 static struct net_device *nr_ax25_dev_get(char *devname)
 585 {
 586         struct net_device *dev;
 587
 588         if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
 589                 return NULL;
 590
 591         if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
 592                 return dev;
 593
 594         dev_put(dev);
 595         return NULL;
 596 }
 597
 598 /*
 599  *      Find the first active NET/ROM device, usually "nr0".
 600  */
 601 struct net_device *nr_dev_first(void)
 602 {
 603         struct net_device *dev, *first = NULL;
 604
 605         rcu_read_lock();
 606         for_each_netdev_rcu(&init_net, dev) {
 607                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
 608                         if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
 609                                 first = dev;
 610         }
 611         if (first)
 612                 dev_hold(first);
 613         rcu_read_unlock();
 614
 615         return first;
 616 }
 617
 618 /*
 619  *      Find the NET/ROM device for the given callsign.
 620  */
 621 struct net_device *nr_dev_get(ax25_address *addr)
 622 {
 623         struct net_device *dev;
 624
 625         rcu_read_lock();
 626         for_each_netdev_rcu(&init_net, dev) {
 627                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
 628                     ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
 629                         dev_hold(dev);
 630                         goto out;
 631                 }
 632         }
 633         dev = NULL;
 634 out:
 635         rcu_read_unlock();
 636         return dev;
 637 }
 638
 639 static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
 640         ax25_address *digipeaters)
 641 {
 642         int i;
 643
 644         if (ndigis == 0)
 645                 return NULL;
 646
 647         for (i = 0; i < ndigis; i++) {
 648                 digi->calls[i]    = digipeaters[i];
 649                 digi->repeated[i] = 0;
 650         }
 651
 652         digi->ndigi      = ndigis;
 653         digi->lastrepeat = -1;
 654
 655         return digi;
 656 }
 657
 658 /*
 659  *      Handle the ioctls that control the routing functions.
 660  */
 661 int nr_rt_ioctl(unsigned int cmd, void __user *arg)
 662 {
 663         struct nr_route_struct nr_route;
 664         struct net_device *dev;
 665         ax25_digi digi;
 666         int ret;
 667
 668         switch (cmd) {
 669         case SIOCADDRT:
 670                 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
 671                         return -EFAULT;
 672                 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
 673                         return -EINVAL;
 674                 if (nr_route.ndigis < 0 || nr_route.ndigis > AX25_MAX_DIGIS) {
 675                         dev_put(dev);
 676                         return -EINVAL;
 677                 }
 678                 switch (nr_route.type) {
 679                 case NETROM_NODE:
 680                         ret = nr_add_node(&nr_route.callsign,
 681                                 nr_route.mnemonic,
 682                                 &nr_route.neighbour,
 683                                 nr_call_to_digi(&digi, nr_route.ndigis,
 684                                                 nr_route.digipeaters),
 685                                 dev, nr_route.quality,
 686                                 nr_route.obs_count);
 687                         break;
 688                 case NETROM_NEIGH:
 689                         ret = nr_add_neigh(&nr_route.callsign,
 690                                 nr_call_to_digi(&digi, nr_route.ndigis,
 691                                                 nr_route.digipeaters),
 692                                 dev, nr_route.quality);
 693                         break;
 694                 default:
 695                         ret = -EINVAL;
 696                 }
 697                 dev_put(dev);
 698                 return ret;
 699
 700         case SIOCDELRT:
 701                 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
 702                         return -EFAULT;
 703                 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
 704                         return -EINVAL;
 705                 switch (nr_route.type) {
 706                 case NETROM_NODE:
 707                         ret = nr_del_node(&nr_route.callsign,
 708                                 &nr_route.neighbour, dev);
 709                         break;
 710                 case NETROM_NEIGH:
 711                         ret = nr_del_neigh(&nr_route.callsign,
 712                                 dev, nr_route.quality);
 713                         break;
 714                 default:
 715                         ret = -EINVAL;
 716                 }
 717                 dev_put(dev);
 718                 return ret;
 719
 720         case SIOCNRDECOBS:
 721                 return nr_dec_obs();
 722
 723         default:
 724                 return -EINVAL;
 725         }
 726
 727         return 0;
 728 }
 729
 730 /*
 731  *      A level 2 link has timed out, therefore it appears to be a poor link,
 732  *      then don't use that neighbour until it is reset.
 733  */
 734 void nr_link_failed(ax25_cb *ax25, int reason)
 735 {
 736         struct nr_neigh *s, *nr_neigh = NULL;
 737         struct hlist_node *node;
 738         struct nr_node  *nr_node = NULL;
 739
 740         spin_lock_bh(&nr_neigh_list_lock);
 741         nr_neigh_for_each(s, node, &nr_neigh_list) {
 742                 if (s->ax25 == ax25) {
 743                         nr_neigh_hold(s);
 744                         nr_neigh = s;
 745                         break;
 746                 }
 747         }
 748         spin_unlock_bh(&nr_neigh_list_lock);
 749
 750         if (nr_neigh == NULL)
 751                 return;
 752
 753         nr_neigh->ax25 = NULL;
 754         ax25_cb_put(ax25);
 755
 756         if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
 757                 nr_neigh_put(nr_neigh);
 758                 return;
 759         }
 760         spin_lock_bh(&nr_node_list_lock);
 761         nr_node_for_each(nr_node, node, &nr_node_list) {
 762                 nr_node_lock(nr_node);
 763                 if (nr_node->which < nr_node->count &&
 764                     nr_node->routes[nr_node->which].neighbour == nr_neigh)
 765                         nr_node->which++;
 766                 nr_node_unlock(nr_node);
 767         }
 768         spin_unlock_bh(&nr_node_list_lock);
 769         nr_neigh_put(nr_neigh);
 770 }
 771
 772 /*
 773  *      Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
 774  *      indicates an internally generated frame.
 775  */
 776 int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
 777 {
 778         ax25_address *nr_src, *nr_dest;
 779         struct nr_neigh *nr_neigh;
 780         struct nr_node  *nr_node;
 781         struct net_device *dev;
 782         unsigned char *dptr;
 783         ax25_cb *ax25s;
 784         int ret;
 785         struct sk_buff *skbn;
 786
 787
 788         nr_src  = (ax25_address *)(skb->data + 0);
 789         nr_dest = (ax25_address *)(skb->data + 7);
 790
 791         if (ax25 != NULL) {
 792                 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
 793                                   ax25->ax25_dev->dev, 0,
 794                                   sysctl_netrom_obsolescence_count_initialiser);
 795                 if (ret)
 796                         return ret;
 797         }
 798
 799         if ((dev = nr_dev_get(nr_dest)) != NULL) {      /* Its for me */
 800                 if (ax25 == NULL)                       /* Its from me */
 801                         ret = nr_loopback_queue(skb);
 802                 else
 803                         ret = nr_rx_frame(skb, dev);
 804                 dev_put(dev);
 805                 return ret;
 806         }
 807
 808         if (!sysctl_netrom_routing_control && ax25 != NULL)
 809                 return 0;
 810
 811         /* Its Time-To-Live has expired */
 812         if (skb->data[14] == 1) {
 813                 return 0;
 814         }
 815
 816         nr_node = nr_node_get(nr_dest);
 817         if (nr_node == NULL)
 818                 return 0;
 819         nr_node_lock(nr_node);
 820
 821         if (nr_node->which >= nr_node->count) {
 822                 nr_node_unlock(nr_node);
 823                 nr_node_put(nr_node);
 824                 return 0;
 825         }
 826
 827         nr_neigh = nr_node->routes[nr_node->which].neighbour;
 828
 829         if ((dev = nr_dev_first()) == NULL) {
 830                 nr_node_unlock(nr_node);
 831                 nr_node_put(nr_node);
 832                 return 0;
 833         }
 834
 835         /* We are going to change the netrom headers so we should get our
 836            own skb, we also did not know until now how much header space
 837            we had to reserve... - RXQ */
 838         if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
 839                 nr_node_unlock(nr_node);
 840                 nr_node_put(nr_node);
 841                 dev_put(dev);
 842                 return 0;
 843         }
 844         kfree_skb(skb);
 845         skb=skbn;
 846         skb->data[14]--;
 847
 848         dptr  = skb_push(skb, 1);
 849         *dptr = AX25_P_NETROM;
 850
 851         ax25s = nr_neigh->ax25;
 852         nr_neigh->ax25 = ax25_send_frame(skb, 256,
 853                                          (ax25_address *)dev->dev_addr,
 854                                          &nr_neigh->callsign,
 855                                          nr_neigh->digipeat, nr_neigh->dev);
 856         if (ax25s)
 857                 ax25_cb_put(ax25s);
 858
 859         dev_put(dev);
 860         ret = (nr_neigh->ax25 != NULL);
 861         nr_node_unlock(nr_node);
 862         nr_node_put(nr_node);
 863
 864         return ret;
 865 }
 866
 867 #ifdef CONFIG_PROC_FS
 868
 869 static void *nr_node_start(struct seq_file *seq, loff_t *pos)
 870 {
 871         spin_lock_bh(&nr_node_list_lock);
 872         return seq_hlist_start_head(&nr_node_list, *pos);
 873 }
 874
 875 static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
 876 {
 877         return seq_hlist_next(v, &nr_node_list, pos);
 878 }
 879
 880 static void nr_node_stop(struct seq_file *seq, void *v)
 881 {
 882         spin_unlock_bh(&nr_node_list_lock);
 883 }
 884
 885 static int nr_node_show(struct seq_file *seq, void *v)
 886 {
 887         char buf[11];
 888         int i;
 889
 890         if (v == SEQ_START_TOKEN)
 891                 seq_puts(seq,
 892                          "callsign  mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
 893         else {
 894                 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
 895                                                       node_node);
 896
 897                 nr_node_lock(nr_node);
 898                 seq_printf(seq, "%-9s %-7s  %d %d",
 899                         ax2asc(buf, &nr_node->callsign),
 900                         (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
 901                         nr_node->which + 1,
 902                         nr_node->count);
 903
 904                 for (i = 0; i < nr_node->count; i++) {
 905                         seq_printf(seq, "  %3d   %d %05d",
 906                                 nr_node->routes[i].quality,
 907                                 nr_node->routes[i].obs_count,
 908                                 nr_node->routes[i].neighbour->number);
 909                 }
 910                 nr_node_unlock(nr_node);
 911
 912                 seq_puts(seq, "\n");
 913         }
 914         return 0;
 915 }
 916
 917 static const struct seq_operations nr_node_seqops = {
 918         .start = nr_node_start,
 919         .next = nr_node_next,
 920         .stop = nr_node_stop,
 921         .show = nr_node_show,
 922 };
 923
 924 static int nr_node_info_open(struct inode *inode, struct file *file)
 925 {
 926         return seq_open(file, &nr_node_seqops);
 927 }
 928
 929 const struct file_operations nr_nodes_fops = {
 930         .owner = THIS_MODULE,
 931         .open = nr_node_info_open,
 932         .read = seq_read,
 933         .llseek = seq_lseek,
 934         .release = seq_release,
 935 };
 936
 937 static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
 938 {
 939         spin_lock_bh(&nr_neigh_list_lock);
 940         return seq_hlist_start_head(&nr_neigh_list, *pos);
 941 }
 942
 943 static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
 944 {
 945         return seq_hlist_next(v, &nr_neigh_list, pos);
 946 }
 947
 948 static void nr_neigh_stop(struct seq_file *seq, void *v)
 949 {
 950         spin_unlock_bh(&nr_neigh_list_lock);
 951 }
 952
 953 static int nr_neigh_show(struct seq_file *seq, void *v)
 954 {
 955         char buf[11];
 956         int i;
 957
 958         if (v == SEQ_START_TOKEN)
 959                 seq_puts(seq, "addr  callsign  dev  qual lock count failed digipeaters\n");
 960         else {
 961                 struct nr_neigh *nr_neigh;
 962
 963                 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
 964                 seq_printf(seq, "%05d %-9s %-4s  %3d    %d   %3d    %3d",
 965                         nr_neigh->number,
 966                         ax2asc(buf, &nr_neigh->callsign),
 967                         nr_neigh->dev ? nr_neigh->dev->name : "???",
 968                         nr_neigh->quality,
 969                         nr_neigh->locked,
 970                         nr_neigh->count,
 971                         nr_neigh->failed);
 972
 973                 if (nr_neigh->digipeat != NULL) {
 974                         for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
 975                                 seq_printf(seq, " %s",
 976                                            ax2asc(buf, &nr_neigh->digipeat->calls[i]));
 977                 }
 978
 979                 seq_puts(seq, "\n");
 980         }
 981         return 0;
 982 }
 983
 984 static const struct seq_operations nr_neigh_seqops = {
 985         .start = nr_neigh_start,
 986         .next = nr_neigh_next,
 987         .stop = nr_neigh_stop,
 988         .show = nr_neigh_show,
 989 };
 990
 991 static int nr_neigh_info_open(struct inode *inode, struct file *file)
 992 {
 993         return seq_open(file, &nr_neigh_seqops);
 994 }
 995
 996 const struct file_operations nr_neigh_fops = {
 997         .owner = THIS_MODULE,
 998         .open = nr_neigh_info_open,
 999         .read = seq_read,
1000         .llseek = seq_lseek,
1001         .release = seq_release,
1002 };
1003
1004 #endif
1005
1006 /*
1007  *      Free all memory associated with the nodes and routes lists.
1008  */
1009 void __exit nr_rt_free(void)
1010 {
1011         struct nr_neigh *s = NULL;
1012         struct nr_node  *t = NULL;
1013         struct hlist_node *node, *nodet;
1014
1015         spin_lock_bh(&nr_neigh_list_lock);
1016         spin_lock_bh(&nr_node_list_lock);
1017         nr_node_for_each_safe(t, node, nodet, &nr_node_list) {
1018                 nr_node_lock(t);
1019                 nr_remove_node_locked(t);
1020                 nr_node_unlock(t);
1021         }
1022         nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
1023                 while(s->count) {
1024                         s->count--;
1025                         nr_neigh_put(s);
1026                 }
1027                 nr_remove_neigh_locked(s);
1028         }
1029         spin_unlock_bh(&nr_node_list_lock);
1030         spin_unlock_bh(&nr_neigh_list_lock);
1031 }