net/decnet/dn_route.c

   1 /*
   2  * DECnet       An implementation of the DECnet protocol suite for the LINUX
   3  *              operating system.  DECnet is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              DECnet Routing Functions (Endnode and Router)
   7  *
   8  * Authors:     Steve Whitehouse <SteveW@ACM.org>
   9  *              Eduardo Marcelo Serrat <emserrat@geocities.com>
  10  *
  11  * Changes:
  12  *              Steve Whitehouse : Fixes to allow "intra-ethernet" and
  13  *                                 "return-to-sender" bits on outgoing
  14  *                                 packets.
  15  *              Steve Whitehouse : Timeouts for cached routes.
  16  *              Steve Whitehouse : Use dst cache for input routes too.
  17  *              Steve Whitehouse : Fixed error values in dn_send_skb.
  18  *              Steve Whitehouse : Rework routing functions to better fit
  19  *                                 DECnet routing design
  20  *              Alexey Kuznetsov : New SMP locking
  21  *              Steve Whitehouse : More SMP locking changes & dn_cache_dump()
  22  *              Steve Whitehouse : Prerouting NF hook, now really is prerouting.
  23  *                                 Fixed possible skb leak in rtnetlink funcs.
  24  *              Steve Whitehouse : Dave Miller's dynamic hash table sizing and
  25  *                                 Alexey Kuznetsov's finer grained locking
  26  *                                 from ipv4/route.c.
  27  *              Steve Whitehouse : Routing is now starting to look like a
  28  *                                 sensible set of code now, mainly due to
  29  *                                 my copying the IPv4 routing code. The
  30  *                                 hooks here are modified and will continue
  31  *                                 to evolve for a while.
  32  *              Steve Whitehouse : Real SMP at last :-) Also new netfilter
  33  *                                 stuff. Look out raw sockets your days
  34  *                                 are numbered!
  35  *              Steve Whitehouse : Added return-to-sender functions. Added
  36  *                                 backlog congestion level return codes.
  37  *              Steve Whitehouse : Fixed bug where routes were set up with
  38  *                                 no ref count on net devices.
  39  *              Steve Whitehouse : RCU for the route cache
  40  *              Steve Whitehouse : Preparations for the flow cache
  41  *              Steve Whitehouse : Prepare for nonlinear skbs
  42  */
  43
  44 /******************************************************************************
  45     (c) 1995-1998 E.M. Serrat           emserrat@geocities.com
  46
  47     This program is free software; you can redistribute it and/or modify
  48     it under the terms of the GNU General Public License as published by
  49     the Free Software Foundation; either version 2 of the License, or
  50     any later version.
  51
  52     This program is distributed in the hope that it will be useful,
  53     but WITHOUT ANY WARRANTY; without even the implied warranty of
  54     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  55     GNU General Public License for more details.
  56 *******************************************************************************/
  57
  58 #include <linux/errno.h>
  59 #include <linux/types.h>
  60 #include <linux/socket.h>
  61 #include <linux/in.h>
  62 #include <linux/kernel.h>
  63 #include <linux/sockios.h>
  64 #include <linux/net.h>
  65 #include <linux/netdevice.h>
  66 #include <linux/inet.h>
  67 #include <linux/route.h>
  68 #include <linux/in_route.h>
  69 #include <linux/slab.h>
  70 #include <net/sock.h>
  71 #include <linux/mm.h>
  72 #include <linux/proc_fs.h>
  73 #include <linux/seq_file.h>
  74 #include <linux/init.h>
  75 #include <linux/rtnetlink.h>
  76 #include <linux/string.h>
  77 #include <linux/netfilter_decnet.h>
  78 #include <linux/rcupdate.h>
  79 #include <linux/times.h>
  80 #include <linux/export.h>
  81 #include <asm/errno.h>
  82 #include <net/net_namespace.h>
  83 #include <net/netlink.h>
  84 #include <net/neighbour.h>
  85 #include <net/dst.h>
  86 #include <net/flow.h>
  87 #include <net/fib_rules.h>
  88 #include <net/dn.h>
  89 #include <net/dn_dev.h>
  90 #include <net/dn_nsp.h>
  91 #include <net/dn_route.h>
  92 #include <net/dn_neigh.h>
  93 #include <net/dn_fib.h>
  94
  95 struct dn_rt_hash_bucket
  96 {
  97         struct dn_route __rcu *chain;
  98         spinlock_t lock;
  99 };
 100
 101 extern struct neigh_table dn_neigh_table;
 102
 103
 104 static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
 105
 106 static const int dn_rt_min_delay = 2 * HZ;
 107 static const int dn_rt_max_delay = 10 * HZ;
 108 static const int dn_rt_mtu_expires = 10 * 60 * HZ;
 109
 110 static unsigned long dn_rt_deadline;
 111
 112 static int dn_dst_gc(struct dst_ops *ops);
 113 static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
 114 static unsigned int dn_dst_default_advmss(const struct dst_entry *dst);
 115 static unsigned int dn_dst_mtu(const struct dst_entry *dst);
 116 static void dn_dst_destroy(struct dst_entry *);
 117 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
 118 static void dn_dst_link_failure(struct sk_buff *);
 119 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
 120 static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, const void *daddr);
 121 static int dn_route_input(struct sk_buff *);
 122 static void dn_run_flush(unsigned long dummy);
 123
 124 static struct dn_rt_hash_bucket *dn_rt_hash_table;
 125 static unsigned dn_rt_hash_mask;
 126
 127 static struct timer_list dn_route_timer;
 128 static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
 129 int decnet_dst_gc_interval = 2;
 130
 131 static struct dst_ops dn_dst_ops = {
 132         .family =               PF_DECnet,
 133         .protocol =             cpu_to_be16(ETH_P_DNA_RT),
 134         .gc_thresh =            128,
 135         .gc =                   dn_dst_gc,
 136         .check =                dn_dst_check,
 137         .default_advmss =       dn_dst_default_advmss,
 138         .mtu =                  dn_dst_mtu,
 139         .cow_metrics =          dst_cow_metrics_generic,
 140         .destroy =              dn_dst_destroy,
 141         .negative_advice =      dn_dst_negative_advice,
 142         .link_failure =         dn_dst_link_failure,
 143         .update_pmtu =          dn_dst_update_pmtu,
 144         .neigh_lookup =         dn_dst_neigh_lookup,
 145 };
 146
 147 static void dn_dst_destroy(struct dst_entry *dst)
 148 {
 149         dst_destroy_metrics_generic(dst);
 150 }
 151
 152 static __inline__ unsigned dn_hash(__le16 src, __le16 dst)
 153 {
 154         __u16 tmp = (__u16 __force)(src ^ dst);
 155         tmp ^= (tmp >> 3);
 156         tmp ^= (tmp >> 5);
 157         tmp ^= (tmp >> 10);
 158         return dn_rt_hash_mask & (unsigned)tmp;
 159 }
 160
 161 static inline void dnrt_free(struct dn_route *rt)
 162 {
 163         call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
 164 }
 165
 166 static inline void dnrt_drop(struct dn_route *rt)
 167 {
 168         dst_release(&rt->dst);
 169         call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
 170 }
 171
 172 static void dn_dst_check_expire(unsigned long dummy)
 173 {
 174         int i;
 175         struct dn_route *rt;
 176         struct dn_route __rcu **rtp;
 177         unsigned long now = jiffies;
 178         unsigned long expire = 120 * HZ;
 179
 180         for (i = 0; i <= dn_rt_hash_mask; i++) {
 181                 rtp = &dn_rt_hash_table[i].chain;
 182
 183                 spin_lock(&dn_rt_hash_table[i].lock);
 184                 while ((rt = rcu_dereference_protected(*rtp,
 185                                                 lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
 186                         if (atomic_read(&rt->dst.__refcnt) ||
 187                                         (now - rt->dst.lastuse) < expire) {
 188                                 rtp = &rt->dst.dn_next;
 189                                 continue;
 190                         }
 191                         *rtp = rt->dst.dn_next;
 192                         rt->dst.dn_next = NULL;
 193                         dnrt_free(rt);
 194                 }
 195                 spin_unlock(&dn_rt_hash_table[i].lock);
 196
 197                 if ((jiffies - now) > 0)
 198                         break;
 199         }
 200
 201         mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ);
 202 }
 203
 204 static int dn_dst_gc(struct dst_ops *ops)
 205 {
 206         struct dn_route *rt;
 207         struct dn_route __rcu **rtp;
 208         int i;
 209         unsigned long now = jiffies;
 210         unsigned long expire = 10 * HZ;
 211
 212         for (i = 0; i <= dn_rt_hash_mask; i++) {
 213
 214                 spin_lock_bh(&dn_rt_hash_table[i].lock);
 215                 rtp = &dn_rt_hash_table[i].chain;
 216
 217                 while ((rt = rcu_dereference_protected(*rtp,
 218                                                 lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
 219                         if (atomic_read(&rt->dst.__refcnt) ||
 220                                         (now - rt->dst.lastuse) < expire) {
 221                                 rtp = &rt->dst.dn_next;
 222                                 continue;
 223                         }
 224                         *rtp = rt->dst.dn_next;
 225                         rt->dst.dn_next = NULL;
 226                         dnrt_drop(rt);
 227                         break;
 228                 }
 229                 spin_unlock_bh(&dn_rt_hash_table[i].lock);
 230         }
 231
 232         return 0;
 233 }
 234
 235 /*
 236  * The decnet standards don't impose a particular minimum mtu, what they
 237  * do insist on is that the routing layer accepts a datagram of at least
 238  * 230 bytes long. Here we have to subtract the routing header length from
 239  * 230 to get the minimum acceptable mtu. If there is no neighbour, then we
 240  * assume the worst and use a long header size.
 241  *
 242  * We update both the mtu and the advertised mss (i.e. the segment size we
 243  * advertise to the other end).
 244  */
 245 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu)
 246 {
 247         struct neighbour *n = dst_get_neighbour(dst);
 248         u32 min_mtu = 230;
 249         struct dn_dev *dn;
 250
 251         dn = n ? rcu_dereference_raw(n->dev->dn_ptr) : NULL;
 252
 253         if (dn && dn->use_long == 0)
 254                 min_mtu -= 6;
 255         else
 256                 min_mtu -= 21;
 257
 258         if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= min_mtu) {
 259                 if (!(dst_metric_locked(dst, RTAX_MTU))) {
 260                         dst_metric_set(dst, RTAX_MTU, mtu);
 261                         dst_set_expires(dst, dn_rt_mtu_expires);
 262                 }
 263                 if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
 264                         u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
 265                         u32 existing_mss = dst_metric_raw(dst, RTAX_ADVMSS);
 266                         if (!existing_mss || existing_mss > mss)
 267                                 dst_metric_set(dst, RTAX_ADVMSS, mss);
 268                 }
 269         }
 270 }
 271
 272 /*
 273  * When a route has been marked obsolete. (e.g. routing cache flush)
 274  */
 275 static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
 276 {
 277         return NULL;
 278 }
 279
 280 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
 281 {
 282         dst_release(dst);
 283         return NULL;
 284 }
 285
 286 static void dn_dst_link_failure(struct sk_buff *skb)
 287 {
 288 }
 289
 290 static inline int compare_keys(struct flowidn *fl1, struct flowidn *fl2)
 291 {
 292         return ((fl1->daddr ^ fl2->daddr) |
 293                 (fl1->saddr ^ fl2->saddr) |
 294                 (fl1->flowidn_mark ^ fl2->flowidn_mark) |
 295                 (fl1->flowidn_scope ^ fl2->flowidn_scope) |
 296                 (fl1->flowidn_oif ^ fl2->flowidn_oif) |
 297                 (fl1->flowidn_iif ^ fl2->flowidn_iif)) == 0;
 298 }
 299
 300 static int dn_insert_route(struct dn_route *rt, unsigned hash, struct dn_route **rp)
 301 {
 302         struct dn_route *rth;
 303         struct dn_route __rcu **rthp;
 304         unsigned long now = jiffies;
 305
 306         rthp = &dn_rt_hash_table[hash].chain;
 307
 308         spin_lock_bh(&dn_rt_hash_table[hash].lock);
 309         while ((rth = rcu_dereference_protected(*rthp,
 310                                                 lockdep_is_held(&dn_rt_hash_table[hash].lock))) != NULL) {
 311                 if (compare_keys(&rth->fld, &rt->fld)) {
 312                         /* Put it first */
 313                         *rthp = rth->dst.dn_next;
 314                         rcu_assign_pointer(rth->dst.dn_next,
 315                                            dn_rt_hash_table[hash].chain);
 316                         rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
 317
 318                         dst_use(&rth->dst, now);
 319                         spin_unlock_bh(&dn_rt_hash_table[hash].lock);
 320
 321                         dnrt_drop(rt);
 322                         *rp = rth;
 323                         return 0;
 324                 }
 325                 rthp = &rth->dst.dn_next;
 326         }
 327
 328         rcu_assign_pointer(rt->dst.dn_next, dn_rt_hash_table[hash].chain);
 329         rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
 330
 331         dst_use(&rt->dst, now);
 332         spin_unlock_bh(&dn_rt_hash_table[hash].lock);
 333         *rp = rt;
 334         return 0;
 335 }
 336
 337 static void dn_run_flush(unsigned long dummy)
 338 {
 339         int i;
 340         struct dn_route *rt, *next;
 341
 342         for (i = 0; i < dn_rt_hash_mask; i++) {
 343                 spin_lock_bh(&dn_rt_hash_table[i].lock);
 344
 345                 if ((rt = xchg((struct dn_route **)&dn_rt_hash_table[i].chain, NULL)) == NULL)
 346                         goto nothing_to_declare;
 347
 348                 for(; rt; rt = next) {
 349                         next = rcu_dereference_raw(rt->dst.dn_next);
 350                         RCU_INIT_POINTER(rt->dst.dn_next, NULL);
 351                         dst_free((struct dst_entry *)rt);
 352                 }
 353
 354 nothing_to_declare:
 355                 spin_unlock_bh(&dn_rt_hash_table[i].lock);
 356         }
 357 }
 358
 359 static DEFINE_SPINLOCK(dn_rt_flush_lock);
 360
 361 void dn_rt_cache_flush(int delay)
 362 {
 363         unsigned long now = jiffies;
 364         int user_mode = !in_interrupt();
 365
 366         if (delay < 0)
 367                 delay = dn_rt_min_delay;
 368
 369         spin_lock_bh(&dn_rt_flush_lock);
 370
 371         if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
 372                 long tmo = (long)(dn_rt_deadline - now);
 373
 374                 if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
 375                         tmo = 0;
 376
 377                 if (delay > tmo)
 378                         delay = tmo;
 379         }
 380
 381         if (delay <= 0) {
 382                 spin_unlock_bh(&dn_rt_flush_lock);
 383                 dn_run_flush(0);
 384                 return;
 385         }
 386
 387         if (dn_rt_deadline == 0)
 388                 dn_rt_deadline = now + dn_rt_max_delay;
 389
 390         dn_rt_flush_timer.expires = now + delay;
 391         add_timer(&dn_rt_flush_timer);
 392         spin_unlock_bh(&dn_rt_flush_lock);
 393 }
 394
 395 /**
 396  * dn_return_short - Return a short packet to its sender
 397  * @skb: The packet to return
 398  *
 399  */
 400 static int dn_return_short(struct sk_buff *skb)
 401 {
 402         struct dn_skb_cb *cb;
 403         unsigned char *ptr;
 404         __le16 *src;
 405         __le16 *dst;
 406
 407         /* Add back headers */
 408         skb_push(skb, skb->data - skb_network_header(skb));
 409
 410         if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
 411                 return NET_RX_DROP;
 412
 413         cb = DN_SKB_CB(skb);
 414         /* Skip packet length and point to flags */
 415         ptr = skb->data + 2;
 416         *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
 417
 418         dst = (__le16 *)ptr;
 419         ptr += 2;
 420         src = (__le16 *)ptr;
 421         ptr += 2;
 422         *ptr = 0; /* Zero hop count */
 423
 424         swap(*src, *dst);
 425
 426         skb->pkt_type = PACKET_OUTGOING;
 427         dn_rt_finish_output(skb, NULL, NULL);
 428         return NET_RX_SUCCESS;
 429 }
 430
 431 /**
 432  * dn_return_long - Return a long packet to its sender
 433  * @skb: The long format packet to return
 434  *
 435  */
 436 static int dn_return_long(struct sk_buff *skb)
 437 {
 438         struct dn_skb_cb *cb;
 439         unsigned char *ptr;
 440         unsigned char *src_addr, *dst_addr;
 441         unsigned char tmp[ETH_ALEN];
 442
 443         /* Add back all headers */
 444         skb_push(skb, skb->data - skb_network_header(skb));
 445
 446         if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
 447                 return NET_RX_DROP;
 448
 449         cb = DN_SKB_CB(skb);
 450         /* Ignore packet length and point to flags */
 451         ptr = skb->data + 2;
 452
 453         /* Skip padding */
 454         if (*ptr & DN_RT_F_PF) {
 455                 char padlen = (*ptr & ~DN_RT_F_PF);
 456                 ptr += padlen;
 457         }
 458
 459         *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
 460         ptr += 2;
 461         dst_addr = ptr;
 462         ptr += 8;
 463         src_addr = ptr;
 464         ptr += 6;
 465         *ptr = 0; /* Zero hop count */
 466
 467         /* Swap source and destination */
 468         memcpy(tmp, src_addr, ETH_ALEN);
 469         memcpy(src_addr, dst_addr, ETH_ALEN);
 470         memcpy(dst_addr, tmp, ETH_ALEN);
 471
 472         skb->pkt_type = PACKET_OUTGOING;
 473         dn_rt_finish_output(skb, dst_addr, src_addr);
 474         return NET_RX_SUCCESS;
 475 }
 476
 477 /**
 478  * dn_route_rx_packet - Try and find a route for an incoming packet
 479  * @skb: The packet to find a route for
 480  *
 481  * Returns: result of input function if route is found, error code otherwise
 482  */
 483 static int dn_route_rx_packet(struct sk_buff *skb)
 484 {
 485         struct dn_skb_cb *cb;
 486         int err;
 487
 488         if ((err = dn_route_input(skb)) == 0)
 489                 return dst_input(skb);
 490
 491         cb = DN_SKB_CB(skb);
 492         if (decnet_debug_level & 4) {
 493                 char *devname = skb->dev ? skb->dev->name : "???";
 494
 495                 printk(KERN_DEBUG
 496                         "DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
 497                         (int)cb->rt_flags, devname, skb->len,
 498                         le16_to_cpu(cb->src), le16_to_cpu(cb->dst),
 499                         err, skb->pkt_type);
 500         }
 501
 502         if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
 503                 switch (cb->rt_flags & DN_RT_PKT_MSK) {
 504                 case DN_RT_PKT_SHORT:
 505                         return dn_return_short(skb);
 506                 case DN_RT_PKT_LONG:
 507                         return dn_return_long(skb);
 508                 }
 509         }
 510
 511         kfree_skb(skb);
 512         return NET_RX_DROP;
 513 }
 514
 515 static int dn_route_rx_long(struct sk_buff *skb)
 516 {
 517         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 518         unsigned char *ptr = skb->data;
 519
 520         if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
 521                 goto drop_it;
 522
 523         skb_pull(skb, 20);
 524         skb_reset_transport_header(skb);
 525
 526         /* Destination info */
 527         ptr += 2;
 528         cb->dst = dn_eth2dn(ptr);
 529         if (memcmp(ptr, dn_hiord_addr, 4) != 0)
 530                 goto drop_it;
 531         ptr += 6;
 532
 533
 534         /* Source info */
 535         ptr += 2;
 536         cb->src = dn_eth2dn(ptr);
 537         if (memcmp(ptr, dn_hiord_addr, 4) != 0)
 538                 goto drop_it;
 539         ptr += 6;
 540         /* Other junk */
 541         ptr++;
 542         cb->hops = *ptr++; /* Visit Count */
 543
 544         return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, skb, skb->dev, NULL,
 545                        dn_route_rx_packet);
 546
 547 drop_it:
 548         kfree_skb(skb);
 549         return NET_RX_DROP;
 550 }
 551
 552
 553
 554 static int dn_route_rx_short(struct sk_buff *skb)
 555 {
 556         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 557         unsigned char *ptr = skb->data;
 558
 559         if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
 560                 goto drop_it;
 561
 562         skb_pull(skb, 5);
 563         skb_reset_transport_header(skb);
 564
 565         cb->dst = *(__le16 *)ptr;
 566         ptr += 2;
 567         cb->src = *(__le16 *)ptr;
 568         ptr += 2;
 569         cb->hops = *ptr & 0x3f;
 570
 571         return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, skb, skb->dev, NULL,
 572                        dn_route_rx_packet);
 573
 574 drop_it:
 575         kfree_skb(skb);
 576         return NET_RX_DROP;
 577 }
 578
 579 static int dn_route_discard(struct sk_buff *skb)
 580 {
 581         /*
 582          * I know we drop the packet here, but thats considered success in
 583          * this case
 584          */
 585         kfree_skb(skb);
 586         return NET_RX_SUCCESS;
 587 }
 588
 589 static int dn_route_ptp_hello(struct sk_buff *skb)
 590 {
 591         dn_dev_hello(skb);
 592         dn_neigh_pointopoint_hello(skb);
 593         return NET_RX_SUCCESS;
 594 }
 595
 596 int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 597 {
 598         struct dn_skb_cb *cb;
 599         unsigned char flags = 0;
 600         __u16 len = le16_to_cpu(*(__le16 *)skb->data);
 601         struct dn_dev *dn = rcu_dereference(dev->dn_ptr);
 602         unsigned char padlen = 0;
 603
 604         if (!net_eq(dev_net(dev), &init_net))
 605                 goto dump_it;
 606
 607         if (dn == NULL)
 608                 goto dump_it;
 609
 610         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 611                 goto out;
 612
 613         if (!pskb_may_pull(skb, 3))
 614                 goto dump_it;
 615
 616         skb_pull(skb, 2);
 617
 618         if (len > skb->len)
 619                 goto dump_it;
 620
 621         skb_trim(skb, len);
 622
 623         flags = *skb->data;
 624
 625         cb = DN_SKB_CB(skb);
 626         cb->stamp = jiffies;
 627         cb->iif = dev->ifindex;
 628
 629         /*
 630          * If we have padding, remove it.
 631          */
 632         if (flags & DN_RT_F_PF) {
 633                 padlen = flags & ~DN_RT_F_PF;
 634                 if (!pskb_may_pull(skb, padlen + 1))
 635                         goto dump_it;
 636                 skb_pull(skb, padlen);
 637                 flags = *skb->data;
 638         }
 639
 640         skb_reset_network_header(skb);
 641
 642         /*
 643          * Weed out future version DECnet
 644          */
 645         if (flags & DN_RT_F_VER)
 646                 goto dump_it;
 647
 648         cb->rt_flags = flags;
 649
 650         if (decnet_debug_level & 1)
 651                 printk(KERN_DEBUG
 652                         "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
 653                         (int)flags, (dev) ? dev->name : "???", len, skb->len,
 654                         padlen);
 655
 656         if (flags & DN_RT_PKT_CNTL) {
 657                 if (unlikely(skb_linearize(skb)))
 658                         goto dump_it;
 659
 660                 switch (flags & DN_RT_CNTL_MSK) {
 661                 case DN_RT_PKT_INIT:
 662                         dn_dev_init_pkt(skb);
 663                         break;
 664                 case DN_RT_PKT_VERI:
 665                         dn_dev_veri_pkt(skb);
 666                         break;
 667                 }
 668
 669                 if (dn->parms.state != DN_DEV_S_RU)
 670                         goto dump_it;
 671
 672                 switch (flags & DN_RT_CNTL_MSK) {
 673                 case DN_RT_PKT_HELO:
 674                         return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 675                                        skb, skb->dev, NULL,
 676                                        dn_route_ptp_hello);
 677
 678                 case DN_RT_PKT_L1RT:
 679                 case DN_RT_PKT_L2RT:
 680                         return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE,
 681                                        skb, skb->dev, NULL,
 682                                        dn_route_discard);
 683                 case DN_RT_PKT_ERTH:
 684                         return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 685                                        skb, skb->dev, NULL,
 686                                        dn_neigh_router_hello);
 687
 688                 case DN_RT_PKT_EEDH:
 689                         return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 690                                        skb, skb->dev, NULL,
 691                                        dn_neigh_endnode_hello);
 692                 }
 693         } else {
 694                 if (dn->parms.state != DN_DEV_S_RU)
 695                         goto dump_it;
 696
 697                 skb_pull(skb, 1); /* Pull flags */
 698
 699                 switch (flags & DN_RT_PKT_MSK) {
 700                 case DN_RT_PKT_LONG:
 701                         return dn_route_rx_long(skb);
 702                 case DN_RT_PKT_SHORT:
 703                         return dn_route_rx_short(skb);
 704                 }
 705         }
 706
 707 dump_it:
 708         kfree_skb(skb);
 709 out:
 710         return NET_RX_DROP;
 711 }
 712
 713 static int dn_to_neigh_output(struct sk_buff *skb)
 714 {
 715         struct dst_entry *dst = skb_dst(skb);
 716         struct neighbour *n = dst_get_neighbour(dst);
 717
 718         return n->output(n, skb);
 719 }
 720
 721 static int dn_output(struct sk_buff *skb)
 722 {
 723         struct dst_entry *dst = skb_dst(skb);
 724         struct dn_route *rt = (struct dn_route *)dst;
 725         struct net_device *dev = dst->dev;
 726         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 727         struct neighbour *neigh;
 728
 729         int err = -EINVAL;
 730
 731         if ((neigh = dst_get_neighbour(dst)) == NULL)
 732                 goto error;
 733
 734         skb->dev = dev;
 735
 736         cb->src = rt->rt_saddr;
 737         cb->dst = rt->rt_daddr;
 738
 739         /*
 740          * Always set the Intra-Ethernet bit on all outgoing packets
 741          * originated on this node. Only valid flag from upper layers
 742          * is return-to-sender-requested. Set hop count to 0 too.
 743          */
 744         cb->rt_flags &= ~DN_RT_F_RQR;
 745         cb->rt_flags |= DN_RT_F_IE;
 746         cb->hops = 0;
 747
 748         return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT, skb, NULL, dev,
 749                        dn_to_neigh_output);
 750
 751 error:
 752         if (net_ratelimit())
 753                 printk(KERN_DEBUG "dn_output: This should not happen\n");
 754
 755         kfree_skb(skb);
 756
 757         return err;
 758 }
 759
 760 static int dn_forward(struct sk_buff *skb)
 761 {
 762         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 763         struct dst_entry *dst = skb_dst(skb);
 764         struct dn_dev *dn_db = rcu_dereference(dst->dev->dn_ptr);
 765         struct dn_route *rt;
 766         int header_len;
 767 #ifdef CONFIG_NETFILTER
 768         struct net_device *dev = skb->dev;
 769 #endif
 770
 771         if (skb->pkt_type != PACKET_HOST)
 772                 goto drop;
 773
 774         /* Ensure that we have enough space for headers */
 775         rt = (struct dn_route *)skb_dst(skb);
 776         header_len = dn_db->use_long ? 21 : 6;
 777         if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+header_len))
 778                 goto drop;
 779
 780         /*
 781          * Hop count exceeded.
 782          */
 783         if (++cb->hops > 30)
 784                 goto drop;
 785
 786         skb->dev = rt->dst.dev;
 787
 788         /*
 789          * If packet goes out same interface it came in on, then set
 790          * the Intra-Ethernet bit. This has no effect for short
 791          * packets, so we don't need to test for them here.
 792          */
 793         cb->rt_flags &= ~DN_RT_F_IE;
 794         if (rt->rt_flags & RTCF_DOREDIRECT)
 795                 cb->rt_flags |= DN_RT_F_IE;
 796
 797         return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD, skb, dev, skb->dev,
 798                        dn_to_neigh_output);
 799
 800 drop:
 801         kfree_skb(skb);
 802         return NET_RX_DROP;
 803 }
 804
 805 /*
 806  * Used to catch bugs. This should never normally get
 807  * called.
 808  */
 809 static int dn_rt_bug(struct sk_buff *skb)
 810 {
 811         if (net_ratelimit()) {
 812                 struct dn_skb_cb *cb = DN_SKB_CB(skb);
 813
 814                 printk(KERN_DEBUG "dn_rt_bug: skb from:%04x to:%04x\n",
 815                                 le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
 816         }
 817
 818         kfree_skb(skb);
 819
 820         return NET_RX_DROP;
 821 }
 822
 823 static unsigned int dn_dst_default_advmss(const struct dst_entry *dst)
 824 {
 825         return dn_mss_from_pmtu(dst->dev, dst_mtu(dst));
 826 }
 827
 828 static unsigned int dn_dst_mtu(const struct dst_entry *dst)
 829 {
 830         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 831
 832         return mtu ? : dst->dev->mtu;
 833 }
 834
 835 static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
 836 {
 837         return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
 838 }
 839
 840 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
 841 {
 842         struct dn_fib_info *fi = res->fi;
 843         struct net_device *dev = rt->dst.dev;
 844         unsigned int mss_metric;
 845         struct neighbour *n;
 846
 847         if (fi) {
 848                 if (DN_FIB_RES_GW(*res) &&
 849                     DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
 850                         rt->rt_gateway = DN_FIB_RES_GW(*res);
 851                 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
 852         }
 853         rt->rt_type = res->type;
 854
 855         if (dev != NULL && dst_get_neighbour(&rt->dst) == NULL) {
 856                 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
 857                 if (IS_ERR(n))
 858                         return PTR_ERR(n);
 859                 dst_set_neighbour(&rt->dst, n);
 860         }
 861
 862         if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
 863                 dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
 864         mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
 865         if (mss_metric) {
 866                 unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
 867                 if (mss_metric > mss)
 868                         dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
 869         }
 870         return 0;
 871 }
 872
 873 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
 874 {
 875         __u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
 876         int match = 16;
 877         while(tmp) {
 878                 tmp >>= 1;
 879                 match--;
 880         }
 881         return match;
 882 }
 883
 884 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
 885 {
 886         __le16 saddr = 0;
 887         struct dn_dev *dn_db;
 888         struct dn_ifaddr *ifa;
 889         int best_match = 0;
 890         int ret;
 891
 892         rcu_read_lock();
 893         dn_db = rcu_dereference(dev->dn_ptr);
 894         for (ifa = rcu_dereference(dn_db->ifa_list);
 895              ifa != NULL;
 896              ifa = rcu_dereference(ifa->ifa_next)) {
 897                 if (ifa->ifa_scope > scope)
 898                         continue;
 899                 if (!daddr) {
 900                         saddr = ifa->ifa_local;
 901                         break;
 902                 }
 903                 ret = dn_match_addr(daddr, ifa->ifa_local);
 904                 if (ret > best_match)
 905                         saddr = ifa->ifa_local;
 906                 if (best_match == 0)
 907                         saddr = ifa->ifa_local;
 908         }
 909         rcu_read_unlock();
 910
 911         return saddr;
 912 }
 913
 914 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
 915 {
 916         return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
 917 }
 918
 919 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
 920 {
 921         __le16 mask = dnet_make_mask(res->prefixlen);
 922         return (daddr&~mask)|res->fi->fib_nh->nh_gw;
 923 }
 924
 925 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard)
 926 {
 927         struct flowidn fld = {
 928                 .daddr = oldflp->daddr,
 929                 .saddr = oldflp->saddr,
 930                 .flowidn_scope = RT_SCOPE_UNIVERSE,
 931                 .flowidn_mark = oldflp->flowidn_mark,
 932                 .flowidn_iif = init_net.loopback_dev->ifindex,
 933                 .flowidn_oif = oldflp->flowidn_oif,
 934         };
 935         struct dn_route *rt = NULL;
 936         struct net_device *dev_out = NULL, *dev;
 937         struct neighbour *neigh = NULL;
 938         unsigned hash;
 939         unsigned flags = 0;
 940         struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
 941         int err;
 942         int free_res = 0;
 943         __le16 gateway = 0;
 944
 945         if (decnet_debug_level & 16)
 946                 printk(KERN_DEBUG
 947                        "dn_route_output_slow: dst=%04x src=%04x mark=%d"
 948                        " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
 949                        le16_to_cpu(oldflp->saddr),
 950                        oldflp->flowidn_mark, init_net.loopback_dev->ifindex,
 951                        oldflp->flowidn_oif);
 952
 953         /* If we have an output interface, verify its a DECnet device */
 954         if (oldflp->flowidn_oif) {
 955                 dev_out = dev_get_by_index(&init_net, oldflp->flowidn_oif);
 956                 err = -ENODEV;
 957                 if (dev_out && dev_out->dn_ptr == NULL) {
 958                         dev_put(dev_out);
 959                         dev_out = NULL;
 960                 }
 961                 if (dev_out == NULL)
 962                         goto out;
 963         }
 964
 965         /* If we have a source address, verify that its a local address */
 966         if (oldflp->saddr) {
 967                 err = -EADDRNOTAVAIL;
 968
 969                 if (dev_out) {
 970                         if (dn_dev_islocal(dev_out, oldflp->saddr))
 971                                 goto source_ok;
 972                         dev_put(dev_out);
 973                         goto out;
 974                 }
 975                 rcu_read_lock();
 976                 for_each_netdev_rcu(&init_net, dev) {
 977                         if (!dev->dn_ptr)
 978                                 continue;
 979                         if (!dn_dev_islocal(dev, oldflp->saddr))
 980                                 continue;
 981                         if ((dev->flags & IFF_LOOPBACK) &&
 982                             oldflp->daddr &&
 983                             !dn_dev_islocal(dev, oldflp->daddr))
 984                                 continue;
 985
 986                         dev_out = dev;
 987                         break;
 988                 }
 989                 rcu_read_unlock();
 990                 if (dev_out == NULL)
 991                         goto out;
 992                 dev_hold(dev_out);
 993 source_ok:
 994                 ;
 995         }
 996
 997         /* No destination? Assume its local */
 998         if (!fld.daddr) {
 999                 fld.daddr = fld.saddr;
1000
1001                 err = -EADDRNOTAVAIL;
1002                 if (dev_out)
1003                         dev_put(dev_out);
1004                 dev_out = init_net.loopback_dev;
1005                 dev_hold(dev_out);
1006                 if (!fld.daddr) {
1007                         fld.daddr =
1008                         fld.saddr = dnet_select_source(dev_out, 0,
1009                                                        RT_SCOPE_HOST);
1010                         if (!fld.daddr)
1011                                 goto out;
1012                 }
1013                 fld.flowidn_oif = init_net.loopback_dev->ifindex;
1014                 res.type = RTN_LOCAL;
1015                 goto make_route;
1016         }
1017
1018         if (decnet_debug_level & 16)
1019                 printk(KERN_DEBUG
1020                        "dn_route_output_slow: initial checks complete."
1021                        " dst=%o4x src=%04x oif=%d try_hard=%d\n",
1022                        le16_to_cpu(fld.daddr), le16_to_cpu(fld.saddr),
1023                        fld.flowidn_oif, try_hard);
1024
1025         /*
1026          * N.B. If the kernel is compiled without router support then
1027          * dn_fib_lookup() will evaluate to non-zero so this if () block
1028          * will always be executed.
1029          */
1030         err = -ESRCH;
1031         if (try_hard || (err = dn_fib_lookup(&fld, &res)) != 0) {
1032                 struct dn_dev *dn_db;
1033                 if (err != -ESRCH)
1034                         goto out;
1035                 /*
1036                  * Here the fallback is basically the standard algorithm for
1037                  * routing in endnodes which is described in the DECnet routing
1038                  * docs
1039                  *
1040                  * If we are not trying hard, look in neighbour cache.
1041                  * The result is tested to ensure that if a specific output
1042                  * device/source address was requested, then we honour that
1043                  * here
1044                  */
1045                 if (!try_hard) {
1046                         neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fld.daddr);
1047                         if (neigh) {
1048                                 if ((oldflp->flowidn_oif &&
1049                                     (neigh->dev->ifindex != oldflp->flowidn_oif)) ||
1050                                     (oldflp->saddr &&
1051                                     (!dn_dev_islocal(neigh->dev,
1052                                                      oldflp->saddr)))) {
1053                                         neigh_release(neigh);
1054                                         neigh = NULL;
1055                                 } else {
1056                                         if (dev_out)
1057                                                 dev_put(dev_out);
1058                                         if (dn_dev_islocal(neigh->dev, fld.daddr)) {
1059                                                 dev_out = init_net.loopback_dev;
1060                                                 res.type = RTN_LOCAL;
1061                                         } else {
1062                                                 dev_out = neigh->dev;
1063                                         }
1064                                         dev_hold(dev_out);
1065                                         goto select_source;
1066                                 }
1067                         }
1068                 }
1069
1070                 /* Not there? Perhaps its a local address */
1071                 if (dev_out == NULL)
1072                         dev_out = dn_dev_get_default();
1073                 err = -ENODEV;
1074                 if (dev_out == NULL)
1075                         goto out;
1076                 dn_db = rcu_dereference_raw(dev_out->dn_ptr);
1077                 /* Possible improvement - check all devices for local addr */
1078                 if (dn_dev_islocal(dev_out, fld.daddr)) {
1079                         dev_put(dev_out);
1080                         dev_out = init_net.loopback_dev;
1081                         dev_hold(dev_out);
1082                         res.type = RTN_LOCAL;
1083                         goto select_source;
1084                 }
1085                 /* Not local either.... try sending it to the default router */
1086                 neigh = neigh_clone(dn_db->router);
1087                 BUG_ON(neigh && neigh->dev != dev_out);
1088
1089                 /* Ok then, we assume its directly connected and move on */
1090 select_source:
1091                 if (neigh)
1092                         gateway = ((struct dn_neigh *)neigh)->addr;
1093                 if (gateway == 0)
1094                         gateway = fld.daddr;
1095                 if (fld.saddr == 0) {
1096                         fld.saddr = dnet_select_source(dev_out, gateway,
1097                                                        res.type == RTN_LOCAL ?
1098                                                        RT_SCOPE_HOST :
1099                                                        RT_SCOPE_LINK);
1100                         if (fld.saddr == 0 && res.type != RTN_LOCAL)
1101                                 goto e_addr;
1102                 }
1103                 fld.flowidn_oif = dev_out->ifindex;
1104                 goto make_route;
1105         }
1106         free_res = 1;
1107
1108         if (res.type == RTN_NAT)
1109                 goto e_inval;
1110
1111         if (res.type == RTN_LOCAL) {
1112                 if (!fld.saddr)
1113                         fld.saddr = fld.daddr;
1114                 if (dev_out)
1115                         dev_put(dev_out);
1116                 dev_out = init_net.loopback_dev;
1117                 dev_hold(dev_out);
1118                 fld.flowidn_oif = dev_out->ifindex;
1119                 if (res.fi)
1120                         dn_fib_info_put(res.fi);
1121                 res.fi = NULL;
1122                 goto make_route;
1123         }
1124
1125         if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1126                 dn_fib_select_multipath(&fld, &res);
1127
1128         /*
1129          * We could add some logic to deal with default routes here and
1130          * get rid of some of the special casing above.
1131          */
1132
1133         if (!fld.saddr)
1134                 fld.saddr = DN_FIB_RES_PREFSRC(res);
1135
1136         if (dev_out)
1137                 dev_put(dev_out);
1138         dev_out = DN_FIB_RES_DEV(res);
1139         dev_hold(dev_out);
1140         fld.flowidn_oif = dev_out->ifindex;
1141         gateway = DN_FIB_RES_GW(res);
1142
1143 make_route:
1144         if (dev_out->flags & IFF_LOOPBACK)
1145                 flags |= RTCF_LOCAL;
1146
1147         rt = dst_alloc(&dn_dst_ops, dev_out, 1, 0, DST_HOST);
1148         if (rt == NULL)
1149                 goto e_nobufs;
1150
1151         memset(&rt->fld, 0, sizeof(rt->fld));
1152         rt->fld.saddr        = oldflp->saddr;
1153         rt->fld.daddr        = oldflp->daddr;
1154         rt->fld.flowidn_oif  = oldflp->flowidn_oif;
1155         rt->fld.flowidn_iif  = 0;
1156         rt->fld.flowidn_mark = oldflp->flowidn_mark;
1157
1158         rt->rt_saddr      = fld.saddr;
1159         rt->rt_daddr      = fld.daddr;
1160         rt->rt_gateway    = gateway ? gateway : fld.daddr;
1161         rt->rt_local_src  = fld.saddr;
1162
1163         rt->rt_dst_map    = fld.daddr;
1164         rt->rt_src_map    = fld.saddr;
1165
1166         dst_set_neighbour(&rt->dst, neigh);
1167         neigh = NULL;
1168
1169         rt->dst.lastuse = jiffies;
1170         rt->dst.output  = dn_output;
1171         rt->dst.input   = dn_rt_bug;
1172         rt->rt_flags      = flags;
1173         if (flags & RTCF_LOCAL)
1174                 rt->dst.input = dn_nsp_rx;
1175
1176         err = dn_rt_set_next_hop(rt, &res);
1177         if (err)
1178                 goto e_neighbour;
1179
1180         hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1181         dn_insert_route(rt, hash, (struct dn_route **)pprt);
1182
1183 done:
1184         if (neigh)
1185                 neigh_release(neigh);
1186         if (free_res)
1187                 dn_fib_res_put(&res);
1188         if (dev_out)
1189                 dev_put(dev_out);
1190 out:
1191         return err;
1192
1193 e_addr:
1194         err = -EADDRNOTAVAIL;
1195         goto done;
1196 e_inval:
1197         err = -EINVAL;
1198         goto done;
1199 e_nobufs:
1200         err = -ENOBUFS;
1201         goto done;
1202 e_neighbour:
1203         dst_free(&rt->dst);
1204         goto e_nobufs;
1205 }
1206
1207
1208 /*
1209  * N.B. The flags may be moved into the flowi at some future stage.
1210  */
1211 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags)
1212 {
1213         unsigned hash = dn_hash(flp->saddr, flp->daddr);
1214         struct dn_route *rt = NULL;
1215
1216         if (!(flags & MSG_TRYHARD)) {
1217                 rcu_read_lock_bh();
1218                 for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
1219                         rt = rcu_dereference_bh(rt->dst.dn_next)) {
1220                         if ((flp->daddr == rt->fld.daddr) &&
1221                             (flp->saddr == rt->fld.saddr) &&
1222                             (flp->flowidn_mark == rt->fld.flowidn_mark) &&
1223                             dn_is_output_route(rt) &&
1224                             (rt->fld.flowidn_oif == flp->flowidn_oif)) {
1225                                 dst_use(&rt->dst, jiffies);
1226                                 rcu_read_unlock_bh();
1227                                 *pprt = &rt->dst;
1228                                 return 0;
1229                         }
1230                 }
1231                 rcu_read_unlock_bh();
1232         }
1233
1234         return dn_route_output_slow(pprt, flp, flags);
1235 }
1236
1237 static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags)
1238 {
1239         int err;
1240
1241         err = __dn_route_output_key(pprt, flp, flags);
1242         if (err == 0 && flp->flowidn_proto) {
1243                 *pprt = xfrm_lookup(&init_net, *pprt,
1244                                     flowidn_to_flowi(flp), NULL, 0);
1245                 if (IS_ERR(*pprt)) {
1246                         err = PTR_ERR(*pprt);
1247                         *pprt = NULL;
1248                 }
1249         }
1250         return err;
1251 }
1252
1253 int dn_route_output_sock(struct dst_entry **pprt, struct flowidn *fl, struct sock *sk, int flags)
1254 {
1255         int err;
1256
1257         err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1258         if (err == 0 && fl->flowidn_proto) {
1259                 if (!(flags & MSG_DONTWAIT))
1260                         fl->flowidn_flags |= FLOWI_FLAG_CAN_SLEEP;
1261                 *pprt = xfrm_lookup(&init_net, *pprt,
1262                                     flowidn_to_flowi(fl), sk, 0);
1263                 if (IS_ERR(*pprt)) {
1264                         err = PTR_ERR(*pprt);
1265                         *pprt = NULL;
1266                 }
1267         }
1268         return err;
1269 }
1270
1271 static int dn_route_input_slow(struct sk_buff *skb)
1272 {
1273         struct dn_route *rt = NULL;
1274         struct dn_skb_cb *cb = DN_SKB_CB(skb);
1275         struct net_device *in_dev = skb->dev;
1276         struct net_device *out_dev = NULL;
1277         struct dn_dev *dn_db;
1278         struct neighbour *neigh = NULL;
1279         unsigned hash;
1280         int flags = 0;
1281         __le16 gateway = 0;
1282         __le16 local_src = 0;
1283         struct flowidn fld = {
1284                 .daddr = cb->dst,
1285                 .saddr = cb->src,
1286                 .flowidn_scope = RT_SCOPE_UNIVERSE,
1287                 .flowidn_mark = skb->mark,
1288                 .flowidn_iif = skb->dev->ifindex,
1289         };
1290         struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1291         int err = -EINVAL;
1292         int free_res = 0;
1293
1294         dev_hold(in_dev);
1295
1296         if ((dn_db = rcu_dereference(in_dev->dn_ptr)) == NULL)
1297                 goto out;
1298
1299         /* Zero source addresses are not allowed */
1300         if (fld.saddr == 0)
1301                 goto out;
1302
1303         /*
1304          * In this case we've just received a packet from a source
1305          * outside ourselves pretending to come from us. We don't
1306          * allow it any further to prevent routing loops, spoofing and
1307          * other nasties. Loopback packets already have the dst attached
1308          * so this only affects packets which have originated elsewhere.
1309          */
1310         err  = -ENOTUNIQ;
1311         if (dn_dev_islocal(in_dev, cb->src))
1312                 goto out;
1313
1314         err = dn_fib_lookup(&fld, &res);
1315         if (err) {
1316                 if (err != -ESRCH)
1317                         goto out;
1318                 /*
1319                  * Is the destination us ?
1320                  */
1321                 if (!dn_dev_islocal(in_dev, cb->dst))
1322                         goto e_inval;
1323
1324                 res.type = RTN_LOCAL;
1325         } else {
1326                 __le16 src_map = fld.saddr;
1327                 free_res = 1;
1328
1329                 out_dev = DN_FIB_RES_DEV(res);
1330                 if (out_dev == NULL) {
1331                         if (net_ratelimit())
1332                                 printk(KERN_CRIT "Bug in dn_route_input_slow() "
1333                                                  "No output device\n");
1334                         goto e_inval;
1335                 }
1336                 dev_hold(out_dev);
1337
1338                 if (res.r)
1339                         src_map = fld.saddr; /* no NAT support for now */
1340
1341                 gateway = DN_FIB_RES_GW(res);
1342                 if (res.type == RTN_NAT) {
1343                         fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res);
1344                         dn_fib_res_put(&res);
1345                         free_res = 0;
1346                         if (dn_fib_lookup(&fld, &res))
1347                                 goto e_inval;
1348                         free_res = 1;
1349                         if (res.type != RTN_UNICAST)
1350                                 goto e_inval;
1351                         flags |= RTCF_DNAT;
1352                         gateway = fld.daddr;
1353                 }
1354                 fld.saddr = src_map;
1355         }
1356
1357         switch(res.type) {
1358         case RTN_UNICAST:
1359                 /*
1360                  * Forwarding check here, we only check for forwarding
1361                  * being turned off, if you want to only forward intra
1362                  * area, its up to you to set the routing tables up
1363                  * correctly.
1364                  */
1365                 if (dn_db->parms.forwarding == 0)
1366                         goto e_inval;
1367
1368                 if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1369                         dn_fib_select_multipath(&fld, &res);
1370
1371                 /*
1372                  * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1373                  * flag as a hint to set the intra-ethernet bit when
1374                  * forwarding. If we've got NAT in operation, we don't do
1375                  * this optimisation.
1376                  */
1377                 if (out_dev == in_dev && !(flags & RTCF_NAT))
1378                         flags |= RTCF_DOREDIRECT;
1379
1380                 local_src = DN_FIB_RES_PREFSRC(res);
1381
1382         case RTN_BLACKHOLE:
1383         case RTN_UNREACHABLE:
1384                 break;
1385         case RTN_LOCAL:
1386                 flags |= RTCF_LOCAL;
1387                 fld.saddr = cb->dst;
1388                 fld.daddr = cb->src;
1389
1390                 /* Routing tables gave us a gateway */
1391                 if (gateway)
1392                         goto make_route;
1393
1394                 /* Packet was intra-ethernet, so we know its on-link */
1395                 if (cb->rt_flags & DN_RT_F_IE) {
1396                         gateway = cb->src;
1397                         flags |= RTCF_DIRECTSRC;
1398                         goto make_route;
1399                 }
1400
1401                 /* Use the default router if there is one */
1402                 neigh = neigh_clone(dn_db->router);
1403                 if (neigh) {
1404                         gateway = ((struct dn_neigh *)neigh)->addr;
1405                         goto make_route;
1406                 }
1407
1408                 /* Close eyes and pray */
1409                 gateway = cb->src;
1410                 flags |= RTCF_DIRECTSRC;
1411                 goto make_route;
1412         default:
1413                 goto e_inval;
1414         }
1415
1416 make_route:
1417         rt = dst_alloc(&dn_dst_ops, out_dev, 0, 0, DST_HOST);
1418         if (rt == NULL)
1419                 goto e_nobufs;
1420
1421         memset(&rt->fld, 0, sizeof(rt->fld));
1422         rt->rt_saddr      = fld.saddr;
1423         rt->rt_daddr      = fld.daddr;
1424         rt->rt_gateway    = fld.daddr;
1425         if (gateway)
1426                 rt->rt_gateway = gateway;
1427         rt->rt_local_src  = local_src ? local_src : rt->rt_saddr;
1428
1429         rt->rt_dst_map    = fld.daddr;
1430         rt->rt_src_map    = fld.saddr;
1431
1432         rt->fld.saddr        = cb->src;
1433         rt->fld.daddr        = cb->dst;
1434         rt->fld.flowidn_oif  = 0;
1435         rt->fld.flowidn_iif  = in_dev->ifindex;
1436         rt->fld.flowidn_mark = fld.flowidn_mark;
1437
1438         dst_set_neighbour(&rt->dst, neigh);
1439         rt->dst.lastuse = jiffies;
1440         rt->dst.output = dn_rt_bug;
1441         switch (res.type) {
1442         case RTN_UNICAST:
1443                 rt->dst.input = dn_forward;
1444                 break;
1445         case RTN_LOCAL:
1446                 rt->dst.output = dn_output;
1447                 rt->dst.input = dn_nsp_rx;
1448                 rt->dst.dev = in_dev;
1449                 flags |= RTCF_LOCAL;
1450                 break;
1451         default:
1452         case RTN_UNREACHABLE:
1453         case RTN_BLACKHOLE:
1454                 rt->dst.input = dst_discard;
1455         }
1456         rt->rt_flags = flags;
1457
1458         err = dn_rt_set_next_hop(rt, &res);
1459         if (err)
1460                 goto e_neighbour;
1461
1462         hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1463         dn_insert_route(rt, hash, &rt);
1464         skb_dst_set(skb, &rt->dst);
1465
1466 done:
1467         if (neigh)
1468                 neigh_release(neigh);
1469         if (free_res)
1470                 dn_fib_res_put(&res);
1471         dev_put(in_dev);
1472         if (out_dev)
1473                 dev_put(out_dev);
1474 out:
1475         return err;
1476
1477 e_inval:
1478         err = -EINVAL;
1479         goto done;
1480
1481 e_nobufs:
1482         err = -ENOBUFS;
1483         goto done;
1484
1485 e_neighbour:
1486         dst_free(&rt->dst);
1487         goto done;
1488 }
1489
1490 static int dn_route_input(struct sk_buff *skb)
1491 {
1492         struct dn_route *rt;
1493         struct dn_skb_cb *cb = DN_SKB_CB(skb);
1494         unsigned hash = dn_hash(cb->src, cb->dst);
1495
1496         if (skb_dst(skb))
1497                 return 0;
1498
1499         rcu_read_lock();
1500         for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1501             rt = rcu_dereference(rt->dst.dn_next)) {
1502                 if ((rt->fld.saddr == cb->src) &&
1503                     (rt->fld.daddr == cb->dst) &&
1504                     (rt->fld.flowidn_oif == 0) &&
1505                     (rt->fld.flowidn_mark == skb->mark) &&
1506                     (rt->fld.flowidn_iif == cb->iif)) {
1507                         dst_use(&rt->dst, jiffies);
1508                         rcu_read_unlock();
1509                         skb_dst_set(skb, (struct dst_entry *)rt);
1510                         return 0;
1511                 }
1512         }
1513         rcu_read_unlock();
1514
1515         return dn_route_input_slow(skb);
1516 }
1517
1518 static int dn_rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1519                            int event, int nowait, unsigned int flags)
1520 {
1521         struct dn_route *rt = (struct dn_route *)skb_dst(skb);
1522         struct rtmsg *r;
1523         struct nlmsghdr *nlh;
1524         unsigned char *b = skb_tail_pointer(skb);
1525         long expires;
1526
1527         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
1528         r = NLMSG_DATA(nlh);
1529         r->rtm_family = AF_DECnet;
1530         r->rtm_dst_len = 16;
1531         r->rtm_src_len = 0;
1532         r->rtm_tos = 0;
1533         r->rtm_table = RT_TABLE_MAIN;
1534         RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
1535         r->rtm_type = rt->rt_type;
1536         r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1537         r->rtm_scope = RT_SCOPE_UNIVERSE;
1538         r->rtm_protocol = RTPROT_UNSPEC;
1539         if (rt->rt_flags & RTCF_NOTIFY)
1540                 r->rtm_flags |= RTM_F_NOTIFY;
1541         RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr);
1542         if (rt->fld.saddr) {
1543                 r->rtm_src_len = 16;
1544                 RTA_PUT(skb, RTA_SRC, 2, &rt->fld.saddr);
1545         }
1546         if (rt->dst.dev)
1547                 RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->dst.dev->ifindex);
1548         /*
1549          * Note to self - change this if input routes reverse direction when
1550          * they deal only with inputs and not with replies like they do
1551          * currently.
1552          */
1553         RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src);
1554         if (rt->rt_daddr != rt->rt_gateway)
1555                 RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway);
1556         if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
1557                 goto rtattr_failure;
1558         expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
1559         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, 0, 0, expires,
1560                                rt->dst.error) < 0)
1561                 goto rtattr_failure;
1562         if (dn_is_input_route(rt))
1563                 RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fld.flowidn_iif);
1564
1565         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1566         return skb->len;
1567
1568 nlmsg_failure:
1569 rtattr_failure:
1570         nlmsg_trim(skb, b);
1571         return -1;
1572 }
1573
1574 /*
1575  * This is called by both endnodes and routers now.
1576  */
1577 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
1578 {
1579         struct net *net = sock_net(in_skb->sk);
1580         struct rtattr **rta = arg;
1581         struct rtmsg *rtm = NLMSG_DATA(nlh);
1582         struct dn_route *rt = NULL;
1583         struct dn_skb_cb *cb;
1584         int err;
1585         struct sk_buff *skb;
1586         struct flowidn fld;
1587
1588         if (!net_eq(net, &init_net))
1589                 return -EINVAL;
1590
1591         memset(&fld, 0, sizeof(fld));
1592         fld.flowidn_proto = DNPROTO_NSP;
1593
1594         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1595         if (skb == NULL)
1596                 return -ENOBUFS;
1597         skb_reset_mac_header(skb);
1598         cb = DN_SKB_CB(skb);
1599
1600         if (rta[RTA_SRC-1])
1601                 memcpy(&fld.saddr, RTA_DATA(rta[RTA_SRC-1]), 2);
1602         if (rta[RTA_DST-1])
1603                 memcpy(&fld.daddr, RTA_DATA(rta[RTA_DST-1]), 2);
1604         if (rta[RTA_IIF-1])
1605                 memcpy(&fld.flowidn_iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
1606
1607         if (fld.flowidn_iif) {
1608                 struct net_device *dev;
1609                 if ((dev = dev_get_by_index(&init_net, fld.flowidn_iif)) == NULL) {
1610                         kfree_skb(skb);
1611                         return -ENODEV;
1612                 }
1613                 if (!dev->dn_ptr) {
1614                         dev_put(dev);
1615                         kfree_skb(skb);
1616                         return -ENODEV;
1617                 }
1618                 skb->protocol = htons(ETH_P_DNA_RT);
1619                 skb->dev = dev;
1620                 cb->src = fld.saddr;
1621                 cb->dst = fld.daddr;
1622                 local_bh_disable();
1623                 err = dn_route_input(skb);
1624                 local_bh_enable();
1625                 memset(cb, 0, sizeof(struct dn_skb_cb));
1626                 rt = (struct dn_route *)skb_dst(skb);
1627                 if (!err && -rt->dst.error)
1628                         err = rt->dst.error;
1629         } else {
1630                 int oif = 0;
1631                 if (rta[RTA_OIF - 1])
1632                         memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
1633                 fld.flowidn_oif = oif;
1634                 err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
1635         }
1636
1637         if (skb->dev)
1638                 dev_put(skb->dev);
1639         skb->dev = NULL;
1640         if (err)
1641                 goto out_free;
1642         skb_dst_set(skb, &rt->dst);
1643         if (rtm->rtm_flags & RTM_F_NOTIFY)
1644                 rt->rt_flags |= RTCF_NOTIFY;
1645
1646         err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1647
1648         if (err == 0)
1649                 goto out_free;
1650         if (err < 0) {
1651                 err = -EMSGSIZE;
1652                 goto out_free;
1653         }
1654
1655         return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).pid);
1656
1657 out_free:
1658         kfree_skb(skb);
1659         return err;
1660 }
1661
1662 /*
1663  * For routers, this is called from dn_fib_dump, but for endnodes its
1664  * called directly from the rtnetlink dispatch table.
1665  */
1666 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1667 {
1668         struct net *net = sock_net(skb->sk);
1669         struct dn_route *rt;
1670         int h, s_h;
1671         int idx, s_idx;
1672
1673         if (!net_eq(net, &init_net))
1674                 return 0;
1675
1676         if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg))
1677                 return -EINVAL;
1678         if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED))
1679                 return 0;
1680
1681         s_h = cb->args[0];
1682         s_idx = idx = cb->args[1];
1683         for(h = 0; h <= dn_rt_hash_mask; h++) {
1684                 if (h < s_h)
1685                         continue;
1686                 if (h > s_h)
1687                         s_idx = 0;
1688                 rcu_read_lock_bh();
1689                 for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
1690                         rt;
1691                         rt = rcu_dereference_bh(rt->dst.dn_next), idx++) {
1692                         if (idx < s_idx)
1693                                 continue;
1694                         skb_dst_set(skb, dst_clone(&rt->dst));
1695                         if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
1696                                         cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1697                                         1, NLM_F_MULTI) <= 0) {
1698                                 skb_dst_drop(skb);
1699                                 rcu_read_unlock_bh();
1700                                 goto done;
1701                         }
1702                         skb_dst_drop(skb);
1703                 }
1704                 rcu_read_unlock_bh();
1705         }
1706
1707 done:
1708         cb->args[0] = h;
1709         cb->args[1] = idx;
1710         return skb->len;
1711 }
1712
1713 #ifdef CONFIG_PROC_FS
1714 struct dn_rt_cache_iter_state {
1715         int bucket;
1716 };
1717
1718 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1719 {
1720         struct dn_route *rt = NULL;
1721         struct dn_rt_cache_iter_state *s = seq->private;
1722
1723         for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1724                 rcu_read_lock_bh();
1725                 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1726                 if (rt)
1727                         break;
1728                 rcu_read_unlock_bh();
1729         }
1730         return rt;
1731 }
1732
1733 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1734 {
1735         struct dn_rt_cache_iter_state *s = seq->private;
1736
1737         rt = rcu_dereference_bh(rt->dst.dn_next);
1738         while (!rt) {
1739                 rcu_read_unlock_bh();
1740                 if (--s->bucket < 0)
1741                         break;
1742                 rcu_read_lock_bh();
1743                 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1744         }
1745         return rt;
1746 }
1747
1748 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1749 {
1750         struct dn_route *rt = dn_rt_cache_get_first(seq);
1751
1752         if (rt) {
1753                 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1754                         --*pos;
1755         }
1756         return *pos ? NULL : rt;
1757 }
1758
1759 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1760 {
1761         struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1762         ++*pos;
1763         return rt;
1764 }
1765
1766 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1767 {
1768         if (v)
1769                 rcu_read_unlock_bh();
1770 }
1771
1772 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1773 {
1774         struct dn_route *rt = v;
1775         char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1776
1777         seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1778                         rt->dst.dev ? rt->dst.dev->name : "*",
1779                         dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
1780                         dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
1781                         atomic_read(&rt->dst.__refcnt),
1782                         rt->dst.__use,
1783                         (int) dst_metric(&rt->dst, RTAX_RTT));
1784         return 0;
1785 }
1786
1787 static const struct seq_operations dn_rt_cache_seq_ops = {
1788         .start  = dn_rt_cache_seq_start,
1789         .next   = dn_rt_cache_seq_next,
1790         .stop   = dn_rt_cache_seq_stop,
1791         .show   = dn_rt_cache_seq_show,
1792 };
1793
1794 static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1795 {
1796         return seq_open_private(file, &dn_rt_cache_seq_ops,
1797                         sizeof(struct dn_rt_cache_iter_state));
1798 }
1799
1800 static const struct file_operations dn_rt_cache_seq_fops = {
1801         .owner   = THIS_MODULE,
1802         .open    = dn_rt_cache_seq_open,
1803         .read    = seq_read,
1804         .llseek  = seq_lseek,
1805         .release = seq_release_private,
1806 };
1807
1808 #endif /* CONFIG_PROC_FS */
1809
1810 void __init dn_route_init(void)
1811 {
1812         int i, goal, order;
1813
1814         dn_dst_ops.kmem_cachep =
1815                 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1816                                   SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1817         dst_entries_init(&dn_dst_ops);
1818         setup_timer(&dn_route_timer, dn_dst_check_expire, 0);
1819         dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1820         add_timer(&dn_route_timer);
1821
1822         goal = totalram_pages >> (26 - PAGE_SHIFT);
1823
1824         for(order = 0; (1UL << order) < goal; order++)
1825                 /* NOTHING */;
1826
1827         /*
1828          * Only want 1024 entries max, since the table is very, very unlikely
1829          * to be larger than that.
1830          */
1831         while(order && ((((1UL << order) * PAGE_SIZE) /
1832                                 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1833                 order--;
1834
1835         do {
1836                 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1837                         sizeof(struct dn_rt_hash_bucket);
1838                 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1839                         dn_rt_hash_mask--;
1840                 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1841                         __get_free_pages(GFP_ATOMIC, order);
1842         } while (dn_rt_hash_table == NULL && --order > 0);
1843
1844         if (!dn_rt_hash_table)
1845                 panic("Failed to allocate DECnet route cache hash table\n");
1846
1847         printk(KERN_INFO
1848                 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1849                 dn_rt_hash_mask,
1850                 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1851
1852         dn_rt_hash_mask--;
1853         for(i = 0; i <= dn_rt_hash_mask; i++) {
1854                 spin_lock_init(&dn_rt_hash_table[i].lock);
1855                 dn_rt_hash_table[i].chain = NULL;
1856         }
1857
1858         dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1859
1860         proc_net_fops_create(&init_net, "decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
1861
1862 #ifdef CONFIG_DECNET_ROUTER
1863         rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1864                       dn_fib_dump, NULL);
1865 #else
1866         rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1867                       dn_cache_dump, NULL);
1868 #endif
1869 }
1870
1871 void __exit dn_route_cleanup(void)
1872 {
1873         del_timer(&dn_route_timer);
1874         dn_run_flush(0);
1875
1876         proc_net_remove(&init_net, "decnet_cache");
1877         dst_entries_destroy(&dn_dst_ops);
1878 }
1879