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_default_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         .default_mtu =          dn_dst_default_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_default_mtu(const struct dst_entry *dst)
 829 {
 830         return dst->dev->mtu;
 831 }
 832
 833 static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
 834 {
 835         return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
 836 }
 837
 838 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
 839 {
 840         struct dn_fib_info *fi = res->fi;
 841         struct net_device *dev = rt->dst.dev;
 842         unsigned int mss_metric;
 843         struct neighbour *n;
 844
 845         if (fi) {
 846                 if (DN_FIB_RES_GW(*res) &&
 847                     DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
 848                         rt->rt_gateway = DN_FIB_RES_GW(*res);
 849                 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
 850         }
 851         rt->rt_type = res->type;
 852
 853         if (dev != NULL && dst_get_neighbour(&rt->dst) == NULL) {
 854                 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
 855                 if (IS_ERR(n))
 856                         return PTR_ERR(n);
 857                 dst_set_neighbour(&rt->dst, n);
 858         }
 859
 860         if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
 861                 dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
 862         mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
 863         if (mss_metric) {
 864                 unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
 865                 if (mss_metric > mss)
 866                         dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
 867         }
 868         return 0;
 869 }
 870
 871 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
 872 {
 873         __u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
 874         int match = 16;
 875         while(tmp) {
 876                 tmp >>= 1;
 877                 match--;
 878         }
 879         return match;
 880 }
 881
 882 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
 883 {
 884         __le16 saddr = 0;
 885         struct dn_dev *dn_db;
 886         struct dn_ifaddr *ifa;
 887         int best_match = 0;
 888         int ret;
 889
 890         rcu_read_lock();
 891         dn_db = rcu_dereference(dev->dn_ptr);
 892         for (ifa = rcu_dereference(dn_db->ifa_list);
 893              ifa != NULL;
 894              ifa = rcu_dereference(ifa->ifa_next)) {
 895                 if (ifa->ifa_scope > scope)
 896                         continue;
 897                 if (!daddr) {
 898                         saddr = ifa->ifa_local;
 899                         break;
 900                 }
 901                 ret = dn_match_addr(daddr, ifa->ifa_local);
 902                 if (ret > best_match)
 903                         saddr = ifa->ifa_local;
 904                 if (best_match == 0)
 905                         saddr = ifa->ifa_local;
 906         }
 907         rcu_read_unlock();
 908
 909         return saddr;
 910 }
 911
 912 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
 913 {
 914         return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
 915 }
 916
 917 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
 918 {
 919         __le16 mask = dnet_make_mask(res->prefixlen);
 920         return (daddr&~mask)|res->fi->fib_nh->nh_gw;
 921 }
 922
 923 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard)
 924 {
 925         struct flowidn fld = {
 926                 .daddr = oldflp->daddr,
 927                 .saddr = oldflp->saddr,
 928                 .flowidn_scope = RT_SCOPE_UNIVERSE,
 929                 .flowidn_mark = oldflp->flowidn_mark,
 930                 .flowidn_iif = init_net.loopback_dev->ifindex,
 931                 .flowidn_oif = oldflp->flowidn_oif,
 932         };
 933         struct dn_route *rt = NULL;
 934         struct net_device *dev_out = NULL, *dev;
 935         struct neighbour *neigh = NULL;
 936         unsigned hash;
 937         unsigned flags = 0;
 938         struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
 939         int err;
 940         int free_res = 0;
 941         __le16 gateway = 0;
 942
 943         if (decnet_debug_level & 16)
 944                 printk(KERN_DEBUG
 945                        "dn_route_output_slow: dst=%04x src=%04x mark=%d"
 946                        " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
 947                        le16_to_cpu(oldflp->saddr),
 948                        oldflp->flowidn_mark, init_net.loopback_dev->ifindex,
 949                        oldflp->flowidn_oif);
 950
 951         /* If we have an output interface, verify its a DECnet device */
 952         if (oldflp->flowidn_oif) {
 953                 dev_out = dev_get_by_index(&init_net, oldflp->flowidn_oif);
 954                 err = -ENODEV;
 955                 if (dev_out && dev_out->dn_ptr == NULL) {
 956                         dev_put(dev_out);
 957                         dev_out = NULL;
 958                 }
 959                 if (dev_out == NULL)
 960                         goto out;
 961         }
 962
 963         /* If we have a source address, verify that its a local address */
 964         if (oldflp->saddr) {
 965                 err = -EADDRNOTAVAIL;
 966
 967                 if (dev_out) {
 968                         if (dn_dev_islocal(dev_out, oldflp->saddr))
 969                                 goto source_ok;
 970                         dev_put(dev_out);
 971                         goto out;
 972                 }
 973                 rcu_read_lock();
 974                 for_each_netdev_rcu(&init_net, dev) {
 975                         if (!dev->dn_ptr)
 976                                 continue;
 977                         if (!dn_dev_islocal(dev, oldflp->saddr))
 978                                 continue;
 979                         if ((dev->flags & IFF_LOOPBACK) &&
 980                             oldflp->daddr &&
 981                             !dn_dev_islocal(dev, oldflp->daddr))
 982                                 continue;
 983
 984                         dev_out = dev;
 985                         break;
 986                 }
 987                 rcu_read_unlock();
 988                 if (dev_out == NULL)
 989                         goto out;
 990                 dev_hold(dev_out);
 991 source_ok:
 992                 ;
 993         }
 994
 995         /* No destination? Assume its local */
 996         if (!fld.daddr) {
 997                 fld.daddr = fld.saddr;
 998
 999                 err = -EADDRNOTAVAIL;
1000                 if (dev_out)
1001                         dev_put(dev_out);
1002                 dev_out = init_net.loopback_dev;
1003                 dev_hold(dev_out);
1004                 if (!fld.daddr) {
1005                         fld.daddr =
1006                         fld.saddr = dnet_select_source(dev_out, 0,
1007                                                        RT_SCOPE_HOST);
1008                         if (!fld.daddr)
1009                                 goto out;
1010                 }
1011                 fld.flowidn_oif = init_net.loopback_dev->ifindex;
1012                 res.type = RTN_LOCAL;
1013                 goto make_route;
1014         }
1015
1016         if (decnet_debug_level & 16)
1017                 printk(KERN_DEBUG
1018                        "dn_route_output_slow: initial checks complete."
1019                        " dst=%o4x src=%04x oif=%d try_hard=%d\n",
1020                        le16_to_cpu(fld.daddr), le16_to_cpu(fld.saddr),
1021                        fld.flowidn_oif, try_hard);
1022
1023         /*
1024          * N.B. If the kernel is compiled without router support then
1025          * dn_fib_lookup() will evaluate to non-zero so this if () block
1026          * will always be executed.
1027          */
1028         err = -ESRCH;
1029         if (try_hard || (err = dn_fib_lookup(&fld, &res)) != 0) {
1030                 struct dn_dev *dn_db;
1031                 if (err != -ESRCH)
1032                         goto out;
1033                 /*
1034                  * Here the fallback is basically the standard algorithm for
1035                  * routing in endnodes which is described in the DECnet routing
1036                  * docs
1037                  *
1038                  * If we are not trying hard, look in neighbour cache.
1039                  * The result is tested to ensure that if a specific output
1040                  * device/source address was requested, then we honour that
1041                  * here
1042                  */
1043                 if (!try_hard) {
1044                         neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fld.daddr);
1045                         if (neigh) {
1046                                 if ((oldflp->flowidn_oif &&
1047                                     (neigh->dev->ifindex != oldflp->flowidn_oif)) ||
1048                                     (oldflp->saddr &&
1049                                     (!dn_dev_islocal(neigh->dev,
1050                                                      oldflp->saddr)))) {
1051                                         neigh_release(neigh);
1052                                         neigh = NULL;
1053                                 } else {
1054                                         if (dev_out)
1055                                                 dev_put(dev_out);
1056                                         if (dn_dev_islocal(neigh->dev, fld.daddr)) {
1057                                                 dev_out = init_net.loopback_dev;
1058                                                 res.type = RTN_LOCAL;
1059                                         } else {
1060                                                 dev_out = neigh->dev;
1061                                         }
1062                                         dev_hold(dev_out);
1063                                         goto select_source;
1064                                 }
1065                         }
1066                 }
1067
1068                 /* Not there? Perhaps its a local address */
1069                 if (dev_out == NULL)
1070                         dev_out = dn_dev_get_default();
1071                 err = -ENODEV;
1072                 if (dev_out == NULL)
1073                         goto out;
1074                 dn_db = rcu_dereference_raw(dev_out->dn_ptr);
1075                 /* Possible improvement - check all devices for local addr */
1076                 if (dn_dev_islocal(dev_out, fld.daddr)) {
1077                         dev_put(dev_out);
1078                         dev_out = init_net.loopback_dev;
1079                         dev_hold(dev_out);
1080                         res.type = RTN_LOCAL;
1081                         goto select_source;
1082                 }
1083                 /* Not local either.... try sending it to the default router */
1084                 neigh = neigh_clone(dn_db->router);
1085                 BUG_ON(neigh && neigh->dev != dev_out);
1086
1087                 /* Ok then, we assume its directly connected and move on */
1088 select_source:
1089                 if (neigh)
1090                         gateway = ((struct dn_neigh *)neigh)->addr;
1091                 if (gateway == 0)
1092                         gateway = fld.daddr;
1093                 if (fld.saddr == 0) {
1094                         fld.saddr = dnet_select_source(dev_out, gateway,
1095                                                        res.type == RTN_LOCAL ?
1096                                                        RT_SCOPE_HOST :
1097                                                        RT_SCOPE_LINK);
1098                         if (fld.saddr == 0 && res.type != RTN_LOCAL)
1099                                 goto e_addr;
1100                 }
1101                 fld.flowidn_oif = dev_out->ifindex;
1102                 goto make_route;
1103         }
1104         free_res = 1;
1105
1106         if (res.type == RTN_NAT)
1107                 goto e_inval;
1108
1109         if (res.type == RTN_LOCAL) {
1110                 if (!fld.saddr)
1111                         fld.saddr = fld.daddr;
1112                 if (dev_out)
1113                         dev_put(dev_out);
1114                 dev_out = init_net.loopback_dev;
1115                 dev_hold(dev_out);
1116                 fld.flowidn_oif = dev_out->ifindex;
1117                 if (res.fi)
1118                         dn_fib_info_put(res.fi);
1119                 res.fi = NULL;
1120                 goto make_route;
1121         }
1122
1123         if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1124                 dn_fib_select_multipath(&fld, &res);
1125
1126         /*
1127          * We could add some logic to deal with default routes here and
1128          * get rid of some of the special casing above.
1129          */
1130
1131         if (!fld.saddr)
1132                 fld.saddr = DN_FIB_RES_PREFSRC(res);
1133
1134         if (dev_out)
1135                 dev_put(dev_out);
1136         dev_out = DN_FIB_RES_DEV(res);
1137         dev_hold(dev_out);
1138         fld.flowidn_oif = dev_out->ifindex;
1139         gateway = DN_FIB_RES_GW(res);
1140
1141 make_route:
1142         if (dev_out->flags & IFF_LOOPBACK)
1143                 flags |= RTCF_LOCAL;
1144
1145         rt = dst_alloc(&dn_dst_ops, dev_out, 1, 0, DST_HOST);
1146         if (rt == NULL)
1147                 goto e_nobufs;
1148
1149         memset(&rt->fld, 0, sizeof(rt->fld));
1150         rt->fld.saddr        = oldflp->saddr;
1151         rt->fld.daddr        = oldflp->daddr;
1152         rt->fld.flowidn_oif  = oldflp->flowidn_oif;
1153         rt->fld.flowidn_iif  = 0;
1154         rt->fld.flowidn_mark = oldflp->flowidn_mark;
1155
1156         rt->rt_saddr      = fld.saddr;
1157         rt->rt_daddr      = fld.daddr;
1158         rt->rt_gateway    = gateway ? gateway : fld.daddr;
1159         rt->rt_local_src  = fld.saddr;
1160
1161         rt->rt_dst_map    = fld.daddr;
1162         rt->rt_src_map    = fld.saddr;
1163
1164         dst_set_neighbour(&rt->dst, neigh);
1165         neigh = NULL;
1166
1167         rt->dst.lastuse = jiffies;
1168         rt->dst.output  = dn_output;
1169         rt->dst.input   = dn_rt_bug;
1170         rt->rt_flags      = flags;
1171         if (flags & RTCF_LOCAL)
1172                 rt->dst.input = dn_nsp_rx;
1173
1174         err = dn_rt_set_next_hop(rt, &res);
1175         if (err)
1176                 goto e_neighbour;
1177
1178         hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1179         dn_insert_route(rt, hash, (struct dn_route **)pprt);
1180
1181 done:
1182         if (neigh)
1183                 neigh_release(neigh);
1184         if (free_res)
1185                 dn_fib_res_put(&res);
1186         if (dev_out)
1187                 dev_put(dev_out);
1188 out:
1189         return err;
1190
1191 e_addr:
1192         err = -EADDRNOTAVAIL;
1193         goto done;
1194 e_inval:
1195         err = -EINVAL;
1196         goto done;
1197 e_nobufs:
1198         err = -ENOBUFS;
1199         goto done;
1200 e_neighbour:
1201         dst_free(&rt->dst);
1202         goto e_nobufs;
1203 }
1204
1205
1206 /*
1207  * N.B. The flags may be moved into the flowi at some future stage.
1208  */
1209 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags)
1210 {
1211         unsigned hash = dn_hash(flp->saddr, flp->daddr);
1212         struct dn_route *rt = NULL;
1213
1214         if (!(flags & MSG_TRYHARD)) {
1215                 rcu_read_lock_bh();
1216                 for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
1217                         rt = rcu_dereference_bh(rt->dst.dn_next)) {
1218                         if ((flp->daddr == rt->fld.daddr) &&
1219                             (flp->saddr == rt->fld.saddr) &&
1220                             (flp->flowidn_mark == rt->fld.flowidn_mark) &&
1221                             dn_is_output_route(rt) &&
1222                             (rt->fld.flowidn_oif == flp->flowidn_oif)) {
1223                                 dst_use(&rt->dst, jiffies);
1224                                 rcu_read_unlock_bh();
1225                                 *pprt = &rt->dst;
1226                                 return 0;
1227                         }
1228                 }
1229                 rcu_read_unlock_bh();
1230         }
1231
1232         return dn_route_output_slow(pprt, flp, flags);
1233 }
1234
1235 static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags)
1236 {
1237         int err;
1238
1239         err = __dn_route_output_key(pprt, flp, flags);
1240         if (err == 0 && flp->flowidn_proto) {
1241                 *pprt = xfrm_lookup(&init_net, *pprt,
1242                                     flowidn_to_flowi(flp), NULL, 0);
1243                 if (IS_ERR(*pprt)) {
1244                         err = PTR_ERR(*pprt);
1245                         *pprt = NULL;
1246                 }
1247         }
1248         return err;
1249 }
1250
1251 int dn_route_output_sock(struct dst_entry **pprt, struct flowidn *fl, struct sock *sk, int flags)
1252 {
1253         int err;
1254
1255         err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1256         if (err == 0 && fl->flowidn_proto) {
1257                 if (!(flags & MSG_DONTWAIT))
1258                         fl->flowidn_flags |= FLOWI_FLAG_CAN_SLEEP;
1259                 *pprt = xfrm_lookup(&init_net, *pprt,
1260                                     flowidn_to_flowi(fl), sk, 0);
1261                 if (IS_ERR(*pprt)) {
1262                         err = PTR_ERR(*pprt);
1263                         *pprt = NULL;
1264                 }
1265         }
1266         return err;
1267 }
1268
1269 static int dn_route_input_slow(struct sk_buff *skb)
1270 {
1271         struct dn_route *rt = NULL;
1272         struct dn_skb_cb *cb = DN_SKB_CB(skb);
1273         struct net_device *in_dev = skb->dev;
1274         struct net_device *out_dev = NULL;
1275         struct dn_dev *dn_db;
1276         struct neighbour *neigh = NULL;
1277         unsigned hash;
1278         int flags = 0;
1279         __le16 gateway = 0;
1280         __le16 local_src = 0;
1281         struct flowidn fld = {
1282                 .daddr = cb->dst,
1283                 .saddr = cb->src,
1284                 .flowidn_scope = RT_SCOPE_UNIVERSE,
1285                 .flowidn_mark = skb->mark,
1286                 .flowidn_iif = skb->dev->ifindex,
1287         };
1288         struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1289         int err = -EINVAL;
1290         int free_res = 0;
1291
1292         dev_hold(in_dev);
1293
1294         if ((dn_db = rcu_dereference(in_dev->dn_ptr)) == NULL)
1295                 goto out;
1296
1297         /* Zero source addresses are not allowed */
1298         if (fld.saddr == 0)
1299                 goto out;
1300
1301         /*
1302          * In this case we've just received a packet from a source
1303          * outside ourselves pretending to come from us. We don't
1304          * allow it any further to prevent routing loops, spoofing and
1305          * other nasties. Loopback packets already have the dst attached
1306          * so this only affects packets which have originated elsewhere.
1307          */
1308         err  = -ENOTUNIQ;
1309         if (dn_dev_islocal(in_dev, cb->src))
1310                 goto out;
1311
1312         err = dn_fib_lookup(&fld, &res);
1313         if (err) {
1314                 if (err != -ESRCH)
1315                         goto out;
1316                 /*
1317                  * Is the destination us ?
1318                  */
1319                 if (!dn_dev_islocal(in_dev, cb->dst))
1320                         goto e_inval;
1321
1322                 res.type = RTN_LOCAL;
1323         } else {
1324                 __le16 src_map = fld.saddr;
1325                 free_res = 1;
1326
1327                 out_dev = DN_FIB_RES_DEV(res);
1328                 if (out_dev == NULL) {
1329                         if (net_ratelimit())
1330                                 printk(KERN_CRIT "Bug in dn_route_input_slow() "
1331                                                  "No output device\n");
1332                         goto e_inval;
1333                 }
1334                 dev_hold(out_dev);
1335
1336                 if (res.r)
1337                         src_map = fld.saddr; /* no NAT support for now */
1338
1339                 gateway = DN_FIB_RES_GW(res);
1340                 if (res.type == RTN_NAT) {
1341                         fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res);
1342                         dn_fib_res_put(&res);
1343                         free_res = 0;
1344                         if (dn_fib_lookup(&fld, &res))
1345                                 goto e_inval;
1346                         free_res = 1;
1347                         if (res.type != RTN_UNICAST)
1348                                 goto e_inval;
1349                         flags |= RTCF_DNAT;
1350                         gateway = fld.daddr;
1351                 }
1352                 fld.saddr = src_map;
1353         }
1354
1355         switch(res.type) {
1356         case RTN_UNICAST:
1357                 /*
1358                  * Forwarding check here, we only check for forwarding
1359                  * being turned off, if you want to only forward intra
1360                  * area, its up to you to set the routing tables up
1361                  * correctly.
1362                  */
1363                 if (dn_db->parms.forwarding == 0)
1364                         goto e_inval;
1365
1366                 if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1367                         dn_fib_select_multipath(&fld, &res);
1368
1369                 /*
1370                  * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1371                  * flag as a hint to set the intra-ethernet bit when
1372                  * forwarding. If we've got NAT in operation, we don't do
1373                  * this optimisation.
1374                  */
1375                 if (out_dev == in_dev && !(flags & RTCF_NAT))
1376                         flags |= RTCF_DOREDIRECT;
1377
1378                 local_src = DN_FIB_RES_PREFSRC(res);
1379
1380         case RTN_BLACKHOLE:
1381         case RTN_UNREACHABLE:
1382                 break;
1383         case RTN_LOCAL:
1384                 flags |= RTCF_LOCAL;
1385                 fld.saddr = cb->dst;
1386                 fld.daddr = cb->src;
1387
1388                 /* Routing tables gave us a gateway */
1389                 if (gateway)
1390                         goto make_route;
1391
1392                 /* Packet was intra-ethernet, so we know its on-link */
1393                 if (cb->rt_flags & DN_RT_F_IE) {
1394                         gateway = cb->src;
1395                         flags |= RTCF_DIRECTSRC;
1396                         goto make_route;
1397                 }
1398
1399                 /* Use the default router if there is one */
1400                 neigh = neigh_clone(dn_db->router);
1401                 if (neigh) {
1402                         gateway = ((struct dn_neigh *)neigh)->addr;
1403                         goto make_route;
1404                 }
1405
1406                 /* Close eyes and pray */
1407                 gateway = cb->src;
1408                 flags |= RTCF_DIRECTSRC;
1409                 goto make_route;
1410         default:
1411                 goto e_inval;
1412         }
1413
1414 make_route:
1415         rt = dst_alloc(&dn_dst_ops, out_dev, 0, 0, DST_HOST);
1416         if (rt == NULL)
1417                 goto e_nobufs;
1418
1419         memset(&rt->fld, 0, sizeof(rt->fld));
1420         rt->rt_saddr      = fld.saddr;
1421         rt->rt_daddr      = fld.daddr;
1422         rt->rt_gateway    = fld.daddr;
1423         if (gateway)
1424                 rt->rt_gateway = gateway;
1425         rt->rt_local_src  = local_src ? local_src : rt->rt_saddr;
1426
1427         rt->rt_dst_map    = fld.daddr;
1428         rt->rt_src_map    = fld.saddr;
1429
1430         rt->fld.saddr        = cb->src;
1431         rt->fld.daddr        = cb->dst;
1432         rt->fld.flowidn_oif  = 0;
1433         rt->fld.flowidn_iif  = in_dev->ifindex;
1434         rt->fld.flowidn_mark = fld.flowidn_mark;
1435
1436         dst_set_neighbour(&rt->dst, neigh);
1437         rt->dst.lastuse = jiffies;
1438         rt->dst.output = dn_rt_bug;
1439         switch (res.type) {
1440         case RTN_UNICAST:
1441                 rt->dst.input = dn_forward;
1442                 break;
1443         case RTN_LOCAL:
1444                 rt->dst.output = dn_output;
1445                 rt->dst.input = dn_nsp_rx;
1446                 rt->dst.dev = in_dev;
1447                 flags |= RTCF_LOCAL;
1448                 break;
1449         default:
1450         case RTN_UNREACHABLE:
1451         case RTN_BLACKHOLE:
1452                 rt->dst.input = dst_discard;
1453         }
1454         rt->rt_flags = flags;
1455
1456         err = dn_rt_set_next_hop(rt, &res);
1457         if (err)
1458                 goto e_neighbour;
1459
1460         hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1461         dn_insert_route(rt, hash, &rt);
1462         skb_dst_set(skb, &rt->dst);
1463
1464 done:
1465         if (neigh)
1466                 neigh_release(neigh);
1467         if (free_res)
1468                 dn_fib_res_put(&res);
1469         dev_put(in_dev);
1470         if (out_dev)
1471                 dev_put(out_dev);
1472 out:
1473         return err;
1474
1475 e_inval:
1476         err = -EINVAL;
1477         goto done;
1478
1479 e_nobufs:
1480         err = -ENOBUFS;
1481         goto done;
1482
1483 e_neighbour:
1484         dst_free(&rt->dst);
1485         goto done;
1486 }
1487
1488 static int dn_route_input(struct sk_buff *skb)
1489 {
1490         struct dn_route *rt;
1491         struct dn_skb_cb *cb = DN_SKB_CB(skb);
1492         unsigned hash = dn_hash(cb->src, cb->dst);
1493
1494         if (skb_dst(skb))
1495                 return 0;
1496
1497         rcu_read_lock();
1498         for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1499             rt = rcu_dereference(rt->dst.dn_next)) {
1500                 if ((rt->fld.saddr == cb->src) &&
1501                     (rt->fld.daddr == cb->dst) &&
1502                     (rt->fld.flowidn_oif == 0) &&
1503                     (rt->fld.flowidn_mark == skb->mark) &&
1504                     (rt->fld.flowidn_iif == cb->iif)) {
1505                         dst_use(&rt->dst, jiffies);
1506                         rcu_read_unlock();
1507                         skb_dst_set(skb, (struct dst_entry *)rt);
1508                         return 0;
1509                 }
1510         }
1511         rcu_read_unlock();
1512
1513         return dn_route_input_slow(skb);
1514 }
1515
1516 static int dn_rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1517                            int event, int nowait, unsigned int flags)
1518 {
1519         struct dn_route *rt = (struct dn_route *)skb_dst(skb);
1520         struct rtmsg *r;
1521         struct nlmsghdr *nlh;
1522         unsigned char *b = skb_tail_pointer(skb);
1523         long expires;
1524
1525         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
1526         r = NLMSG_DATA(nlh);
1527         r->rtm_family = AF_DECnet;
1528         r->rtm_dst_len = 16;
1529         r->rtm_src_len = 0;
1530         r->rtm_tos = 0;
1531         r->rtm_table = RT_TABLE_MAIN;
1532         RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
1533         r->rtm_type = rt->rt_type;
1534         r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1535         r->rtm_scope = RT_SCOPE_UNIVERSE;
1536         r->rtm_protocol = RTPROT_UNSPEC;
1537         if (rt->rt_flags & RTCF_NOTIFY)
1538                 r->rtm_flags |= RTM_F_NOTIFY;
1539         RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr);
1540         if (rt->fld.saddr) {
1541                 r->rtm_src_len = 16;
1542                 RTA_PUT(skb, RTA_SRC, 2, &rt->fld.saddr);
1543         }
1544         if (rt->dst.dev)
1545                 RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->dst.dev->ifindex);
1546         /*
1547          * Note to self - change this if input routes reverse direction when
1548          * they deal only with inputs and not with replies like they do
1549          * currently.
1550          */
1551         RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src);
1552         if (rt->rt_daddr != rt->rt_gateway)
1553                 RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway);
1554         if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
1555                 goto rtattr_failure;
1556         expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
1557         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, 0, 0, expires,
1558                                rt->dst.error) < 0)
1559                 goto rtattr_failure;
1560         if (dn_is_input_route(rt))
1561                 RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fld.flowidn_iif);
1562
1563         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1564         return skb->len;
1565
1566 nlmsg_failure:
1567 rtattr_failure:
1568         nlmsg_trim(skb, b);
1569         return -1;
1570 }
1571
1572 /*
1573  * This is called by both endnodes and routers now.
1574  */
1575 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
1576 {
1577         struct net *net = sock_net(in_skb->sk);
1578         struct rtattr **rta = arg;
1579         struct rtmsg *rtm = NLMSG_DATA(nlh);
1580         struct dn_route *rt = NULL;
1581         struct dn_skb_cb *cb;
1582         int err;
1583         struct sk_buff *skb;
1584         struct flowidn fld;
1585
1586         if (!net_eq(net, &init_net))
1587                 return -EINVAL;
1588
1589         memset(&fld, 0, sizeof(fld));
1590         fld.flowidn_proto = DNPROTO_NSP;
1591
1592         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1593         if (skb == NULL)
1594                 return -ENOBUFS;
1595         skb_reset_mac_header(skb);
1596         cb = DN_SKB_CB(skb);
1597
1598         if (rta[RTA_SRC-1])
1599                 memcpy(&fld.saddr, RTA_DATA(rta[RTA_SRC-1]), 2);
1600         if (rta[RTA_DST-1])
1601                 memcpy(&fld.daddr, RTA_DATA(rta[RTA_DST-1]), 2);
1602         if (rta[RTA_IIF-1])
1603                 memcpy(&fld.flowidn_iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
1604
1605         if (fld.flowidn_iif) {
1606                 struct net_device *dev;
1607                 if ((dev = dev_get_by_index(&init_net, fld.flowidn_iif)) == NULL) {
1608                         kfree_skb(skb);
1609                         return -ENODEV;
1610                 }
1611                 if (!dev->dn_ptr) {
1612                         dev_put(dev);
1613                         kfree_skb(skb);
1614                         return -ENODEV;
1615                 }
1616                 skb->protocol = htons(ETH_P_DNA_RT);
1617                 skb->dev = dev;
1618                 cb->src = fld.saddr;
1619                 cb->dst = fld.daddr;
1620                 local_bh_disable();
1621                 err = dn_route_input(skb);
1622                 local_bh_enable();
1623                 memset(cb, 0, sizeof(struct dn_skb_cb));
1624                 rt = (struct dn_route *)skb_dst(skb);
1625                 if (!err && -rt->dst.error)
1626                         err = rt->dst.error;
1627         } else {
1628                 int oif = 0;
1629                 if (rta[RTA_OIF - 1])
1630                         memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
1631                 fld.flowidn_oif = oif;
1632                 err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
1633         }
1634
1635         if (skb->dev)
1636                 dev_put(skb->dev);
1637         skb->dev = NULL;
1638         if (err)
1639                 goto out_free;
1640         skb_dst_set(skb, &rt->dst);
1641         if (rtm->rtm_flags & RTM_F_NOTIFY)
1642                 rt->rt_flags |= RTCF_NOTIFY;
1643
1644         err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1645
1646         if (err == 0)
1647                 goto out_free;
1648         if (err < 0) {
1649                 err = -EMSGSIZE;
1650                 goto out_free;
1651         }
1652
1653         return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).pid);
1654
1655 out_free:
1656         kfree_skb(skb);
1657         return err;
1658 }
1659
1660 /*
1661  * For routers, this is called from dn_fib_dump, but for endnodes its
1662  * called directly from the rtnetlink dispatch table.
1663  */
1664 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1665 {
1666         struct net *net = sock_net(skb->sk);
1667         struct dn_route *rt;
1668         int h, s_h;
1669         int idx, s_idx;
1670
1671         if (!net_eq(net, &init_net))
1672                 return 0;
1673
1674         if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg))
1675                 return -EINVAL;
1676         if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED))
1677                 return 0;
1678
1679         s_h = cb->args[0];
1680         s_idx = idx = cb->args[1];
1681         for(h = 0; h <= dn_rt_hash_mask; h++) {
1682                 if (h < s_h)
1683                         continue;
1684                 if (h > s_h)
1685                         s_idx = 0;
1686                 rcu_read_lock_bh();
1687                 for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
1688                         rt;
1689                         rt = rcu_dereference_bh(rt->dst.dn_next), idx++) {
1690                         if (idx < s_idx)
1691                                 continue;
1692                         skb_dst_set(skb, dst_clone(&rt->dst));
1693                         if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
1694                                         cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1695                                         1, NLM_F_MULTI) <= 0) {
1696                                 skb_dst_drop(skb);
1697                                 rcu_read_unlock_bh();
1698                                 goto done;
1699                         }
1700                         skb_dst_drop(skb);
1701                 }
1702                 rcu_read_unlock_bh();
1703         }
1704
1705 done:
1706         cb->args[0] = h;
1707         cb->args[1] = idx;
1708         return skb->len;
1709 }
1710
1711 #ifdef CONFIG_PROC_FS
1712 struct dn_rt_cache_iter_state {
1713         int bucket;
1714 };
1715
1716 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1717 {
1718         struct dn_route *rt = NULL;
1719         struct dn_rt_cache_iter_state *s = seq->private;
1720
1721         for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1722                 rcu_read_lock_bh();
1723                 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1724                 if (rt)
1725                         break;
1726                 rcu_read_unlock_bh();
1727         }
1728         return rt;
1729 }
1730
1731 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1732 {
1733         struct dn_rt_cache_iter_state *s = seq->private;
1734
1735         rt = rcu_dereference_bh(rt->dst.dn_next);
1736         while (!rt) {
1737                 rcu_read_unlock_bh();
1738                 if (--s->bucket < 0)
1739                         break;
1740                 rcu_read_lock_bh();
1741                 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1742         }
1743         return rt;
1744 }
1745
1746 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1747 {
1748         struct dn_route *rt = dn_rt_cache_get_first(seq);
1749
1750         if (rt) {
1751                 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1752                         --*pos;
1753         }
1754         return *pos ? NULL : rt;
1755 }
1756
1757 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1758 {
1759         struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1760         ++*pos;
1761         return rt;
1762 }
1763
1764 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1765 {
1766         if (v)
1767                 rcu_read_unlock_bh();
1768 }
1769
1770 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1771 {
1772         struct dn_route *rt = v;
1773         char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1774
1775         seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1776                         rt->dst.dev ? rt->dst.dev->name : "*",
1777                         dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
1778                         dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
1779                         atomic_read(&rt->dst.__refcnt),
1780                         rt->dst.__use,
1781                         (int) dst_metric(&rt->dst, RTAX_RTT));
1782         return 0;
1783 }
1784
1785 static const struct seq_operations dn_rt_cache_seq_ops = {
1786         .start  = dn_rt_cache_seq_start,
1787         .next   = dn_rt_cache_seq_next,
1788         .stop   = dn_rt_cache_seq_stop,
1789         .show   = dn_rt_cache_seq_show,
1790 };
1791
1792 static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1793 {
1794         return seq_open_private(file, &dn_rt_cache_seq_ops,
1795                         sizeof(struct dn_rt_cache_iter_state));
1796 }
1797
1798 static const struct file_operations dn_rt_cache_seq_fops = {
1799         .owner   = THIS_MODULE,
1800         .open    = dn_rt_cache_seq_open,
1801         .read    = seq_read,
1802         .llseek  = seq_lseek,
1803         .release = seq_release_private,
1804 };
1805
1806 #endif /* CONFIG_PROC_FS */
1807
1808 void __init dn_route_init(void)
1809 {
1810         int i, goal, order;
1811
1812         dn_dst_ops.kmem_cachep =
1813                 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1814                                   SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1815         dst_entries_init(&dn_dst_ops);
1816         setup_timer(&dn_route_timer, dn_dst_check_expire, 0);
1817         dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1818         add_timer(&dn_route_timer);
1819
1820         goal = totalram_pages >> (26 - PAGE_SHIFT);
1821
1822         for(order = 0; (1UL << order) < goal; order++)
1823                 /* NOTHING */;
1824
1825         /*
1826          * Only want 1024 entries max, since the table is very, very unlikely
1827          * to be larger than that.
1828          */
1829         while(order && ((((1UL << order) * PAGE_SIZE) /
1830                                 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1831                 order--;
1832
1833         do {
1834                 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1835                         sizeof(struct dn_rt_hash_bucket);
1836                 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1837                         dn_rt_hash_mask--;
1838                 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1839                         __get_free_pages(GFP_ATOMIC, order);
1840         } while (dn_rt_hash_table == NULL && --order > 0);
1841
1842         if (!dn_rt_hash_table)
1843                 panic("Failed to allocate DECnet route cache hash table\n");
1844
1845         printk(KERN_INFO
1846                 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1847                 dn_rt_hash_mask,
1848                 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1849
1850         dn_rt_hash_mask--;
1851         for(i = 0; i <= dn_rt_hash_mask; i++) {
1852                 spin_lock_init(&dn_rt_hash_table[i].lock);
1853                 dn_rt_hash_table[i].chain = NULL;
1854         }
1855
1856         dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1857
1858         proc_net_fops_create(&init_net, "decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
1859
1860 #ifdef CONFIG_DECNET_ROUTER
1861         rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1862                       dn_fib_dump, NULL);
1863 #else
1864         rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1865                       dn_cache_dump, NULL);
1866 #endif
1867 }
1868
1869 void __exit dn_route_cleanup(void)
1870 {
1871         del_timer(&dn_route_timer);
1872         dn_run_flush(0);
1873
1874         proc_net_remove(&init_net, "decnet_cache");
1875         dst_entries_destroy(&dn_dst_ops);
1876 }
1877