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 int 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 int 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 int)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_noref(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 int 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_noref(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
 728         int err = -EINVAL;
 729
 730         if (dst_get_neighbour_noref(dst) == NULL)
 731                 goto error;
 732
 733         skb->dev = dev;
 734
 735         cb->src = rt->rt_saddr;
 736         cb->dst = rt->rt_daddr;
 737
 738         /*
 739          * Always set the Intra-Ethernet bit on all outgoing packets
 740          * originated on this node. Only valid flag from upper layers
 741          * is return-to-sender-requested. Set hop count to 0 too.
 742          */
 743         cb->rt_flags &= ~DN_RT_F_RQR;
 744         cb->rt_flags |= DN_RT_F_IE;
 745         cb->hops = 0;
 746
 747         return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT, skb, NULL, dev,
 748                        dn_to_neigh_output);
 749
 750 error:
 751         net_dbg_ratelimited("dn_output: This should not happen\n");
 752
 753         kfree_skb(skb);
 754
 755         return err;
 756 }
 757
 758 static int dn_forward(struct sk_buff *skb)
 759 {
 760         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 761         struct dst_entry *dst = skb_dst(skb);
 762         struct dn_dev *dn_db = rcu_dereference(dst->dev->dn_ptr);
 763         struct dn_route *rt;
 764         int header_len;
 765 #ifdef CONFIG_NETFILTER
 766         struct net_device *dev = skb->dev;
 767 #endif
 768
 769         if (skb->pkt_type != PACKET_HOST)
 770                 goto drop;
 771
 772         /* Ensure that we have enough space for headers */
 773         rt = (struct dn_route *)skb_dst(skb);
 774         header_len = dn_db->use_long ? 21 : 6;
 775         if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+header_len))
 776                 goto drop;
 777
 778         /*
 779          * Hop count exceeded.
 780          */
 781         if (++cb->hops > 30)
 782                 goto drop;
 783
 784         skb->dev = rt->dst.dev;
 785
 786         /*
 787          * If packet goes out same interface it came in on, then set
 788          * the Intra-Ethernet bit. This has no effect for short
 789          * packets, so we don't need to test for them here.
 790          */
 791         cb->rt_flags &= ~DN_RT_F_IE;
 792         if (rt->rt_flags & RTCF_DOREDIRECT)
 793                 cb->rt_flags |= DN_RT_F_IE;
 794
 795         return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD, skb, dev, skb->dev,
 796                        dn_to_neigh_output);
 797
 798 drop:
 799         kfree_skb(skb);
 800         return NET_RX_DROP;
 801 }
 802
 803 /*
 804  * Used to catch bugs. This should never normally get
 805  * called.
 806  */
 807 static int dn_rt_bug(struct sk_buff *skb)
 808 {
 809         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 810
 811         net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
 812                             le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
 813
 814         kfree_skb(skb);
 815
 816         return NET_RX_DROP;
 817 }
 818
 819 static unsigned int dn_dst_default_advmss(const struct dst_entry *dst)
 820 {
 821         return dn_mss_from_pmtu(dst->dev, dst_mtu(dst));
 822 }
 823
 824 static unsigned int dn_dst_mtu(const struct dst_entry *dst)
 825 {
 826         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 827
 828         return mtu ? : dst->dev->mtu;
 829 }
 830
 831 static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
 832 {
 833         return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
 834 }
 835
 836 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
 837 {
 838         struct dn_fib_info *fi = res->fi;
 839         struct net_device *dev = rt->dst.dev;
 840         unsigned int mss_metric;
 841         struct neighbour *n;
 842
 843         if (fi) {
 844                 if (DN_FIB_RES_GW(*res) &&
 845                     DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
 846                         rt->rt_gateway = DN_FIB_RES_GW(*res);
 847                 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
 848         }
 849         rt->rt_type = res->type;
 850
 851         if (dev != NULL && dst_get_neighbour_noref(&rt->dst) == NULL) {
 852                 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
 853                 if (IS_ERR(n))
 854                         return PTR_ERR(n);
 855                 dst_set_neighbour(&rt->dst, n);
 856         }
 857
 858         if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
 859                 dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
 860         mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
 861         if (mss_metric) {
 862                 unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
 863                 if (mss_metric > mss)
 864                         dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
 865         }
 866         return 0;
 867 }
 868
 869 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
 870 {
 871         __u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
 872         int match = 16;
 873         while(tmp) {
 874                 tmp >>= 1;
 875                 match--;
 876         }
 877         return match;
 878 }
 879
 880 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
 881 {
 882         __le16 saddr = 0;
 883         struct dn_dev *dn_db;
 884         struct dn_ifaddr *ifa;
 885         int best_match = 0;
 886         int ret;
 887
 888         rcu_read_lock();
 889         dn_db = rcu_dereference(dev->dn_ptr);
 890         for (ifa = rcu_dereference(dn_db->ifa_list);
 891              ifa != NULL;
 892              ifa = rcu_dereference(ifa->ifa_next)) {
 893                 if (ifa->ifa_scope > scope)
 894                         continue;
 895                 if (!daddr) {
 896                         saddr = ifa->ifa_local;
 897                         break;
 898                 }
 899                 ret = dn_match_addr(daddr, ifa->ifa_local);
 900                 if (ret > best_match)
 901                         saddr = ifa->ifa_local;
 902                 if (best_match == 0)
 903                         saddr = ifa->ifa_local;
 904         }
 905         rcu_read_unlock();
 906
 907         return saddr;
 908 }
 909
 910 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
 911 {
 912         return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
 913 }
 914
 915 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
 916 {
 917         __le16 mask = dnet_make_mask(res->prefixlen);
 918         return (daddr&~mask)|res->fi->fib_nh->nh_gw;
 919 }
 920
 921 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard)
 922 {
 923         struct flowidn fld = {
 924                 .daddr = oldflp->daddr,
 925                 .saddr = oldflp->saddr,
 926                 .flowidn_scope = RT_SCOPE_UNIVERSE,
 927                 .flowidn_mark = oldflp->flowidn_mark,
 928                 .flowidn_iif = init_net.loopback_dev->ifindex,
 929                 .flowidn_oif = oldflp->flowidn_oif,
 930         };
 931         struct dn_route *rt = NULL;
 932         struct net_device *dev_out = NULL, *dev;
 933         struct neighbour *neigh = NULL;
 934         unsigned int hash;
 935         unsigned int flags = 0;
 936         struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
 937         int err;
 938         int free_res = 0;
 939         __le16 gateway = 0;
 940
 941         if (decnet_debug_level & 16)
 942                 printk(KERN_DEBUG
 943                        "dn_route_output_slow: dst=%04x src=%04x mark=%d"
 944                        " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
 945                        le16_to_cpu(oldflp->saddr),
 946                        oldflp->flowidn_mark, init_net.loopback_dev->ifindex,
 947                        oldflp->flowidn_oif);
 948
 949         /* If we have an output interface, verify its a DECnet device */
 950         if (oldflp->flowidn_oif) {
 951                 dev_out = dev_get_by_index(&init_net, oldflp->flowidn_oif);
 952                 err = -ENODEV;
 953                 if (dev_out && dev_out->dn_ptr == NULL) {
 954                         dev_put(dev_out);
 955                         dev_out = NULL;
 956                 }
 957                 if (dev_out == NULL)
 958                         goto out;
 959         }
 960
 961         /* If we have a source address, verify that its a local address */
 962         if (oldflp->saddr) {
 963                 err = -EADDRNOTAVAIL;
 964
 965                 if (dev_out) {
 966                         if (dn_dev_islocal(dev_out, oldflp->saddr))
 967                                 goto source_ok;
 968                         dev_put(dev_out);
 969                         goto out;
 970                 }
 971                 rcu_read_lock();
 972                 for_each_netdev_rcu(&init_net, dev) {
 973                         if (!dev->dn_ptr)
 974                                 continue;
 975                         if (!dn_dev_islocal(dev, oldflp->saddr))
 976                                 continue;
 977                         if ((dev->flags & IFF_LOOPBACK) &&
 978                             oldflp->daddr &&
 979                             !dn_dev_islocal(dev, oldflp->daddr))
 980                                 continue;
 981
 982                         dev_out = dev;
 983                         break;
 984                 }
 985                 rcu_read_unlock();
 986                 if (dev_out == NULL)
 987                         goto out;
 988                 dev_hold(dev_out);
 989 source_ok:
 990                 ;
 991         }
 992
 993         /* No destination? Assume its local */
 994         if (!fld.daddr) {
 995                 fld.daddr = fld.saddr;
 996
 997                 err = -EADDRNOTAVAIL;
 998                 if (dev_out)
 999                         dev_put(dev_out);
1000                 dev_out = init_net.loopback_dev;
1001                 dev_hold(dev_out);
1002                 if (!fld.daddr) {
1003                         fld.daddr =
1004                         fld.saddr = dnet_select_source(dev_out, 0,
1005                                                        RT_SCOPE_HOST);
1006                         if (!fld.daddr)
1007                                 goto out;
1008                 }
1009                 fld.flowidn_oif = init_net.loopback_dev->ifindex;
1010                 res.type = RTN_LOCAL;
1011                 goto make_route;
1012         }
1013
1014         if (decnet_debug_level & 16)
1015                 printk(KERN_DEBUG
1016                        "dn_route_output_slow: initial checks complete."
1017                        " dst=%o4x src=%04x oif=%d try_hard=%d\n",
1018                        le16_to_cpu(fld.daddr), le16_to_cpu(fld.saddr),
1019                        fld.flowidn_oif, try_hard);
1020
1021         /*
1022          * N.B. If the kernel is compiled without router support then
1023          * dn_fib_lookup() will evaluate to non-zero so this if () block
1024          * will always be executed.
1025          */
1026         err = -ESRCH;
1027         if (try_hard || (err = dn_fib_lookup(&fld, &res)) != 0) {
1028                 struct dn_dev *dn_db;
1029                 if (err != -ESRCH)
1030                         goto out;
1031                 /*
1032                  * Here the fallback is basically the standard algorithm for
1033                  * routing in endnodes which is described in the DECnet routing
1034                  * docs
1035                  *
1036                  * If we are not trying hard, look in neighbour cache.
1037                  * The result is tested to ensure that if a specific output
1038                  * device/source address was requested, then we honour that
1039                  * here
1040                  */
1041                 if (!try_hard) {
1042                         neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fld.daddr);
1043                         if (neigh) {
1044                                 if ((oldflp->flowidn_oif &&
1045                                     (neigh->dev->ifindex != oldflp->flowidn_oif)) ||
1046                                     (oldflp->saddr &&
1047                                     (!dn_dev_islocal(neigh->dev,
1048                                                      oldflp->saddr)))) {
1049                                         neigh_release(neigh);
1050                                         neigh = NULL;
1051                                 } else {
1052                                         if (dev_out)
1053                                                 dev_put(dev_out);
1054                                         if (dn_dev_islocal(neigh->dev, fld.daddr)) {
1055                                                 dev_out = init_net.loopback_dev;
1056                                                 res.type = RTN_LOCAL;
1057                                         } else {
1058                                                 dev_out = neigh->dev;
1059                                         }
1060                                         dev_hold(dev_out);
1061                                         goto select_source;
1062                                 }
1063                         }
1064                 }
1065
1066                 /* Not there? Perhaps its a local address */
1067                 if (dev_out == NULL)
1068                         dev_out = dn_dev_get_default();
1069                 err = -ENODEV;
1070                 if (dev_out == NULL)
1071                         goto out;
1072                 dn_db = rcu_dereference_raw(dev_out->dn_ptr);
1073                 /* Possible improvement - check all devices for local addr */
1074                 if (dn_dev_islocal(dev_out, fld.daddr)) {
1075                         dev_put(dev_out);
1076                         dev_out = init_net.loopback_dev;
1077                         dev_hold(dev_out);
1078                         res.type = RTN_LOCAL;
1079                         goto select_source;
1080                 }
1081                 /* Not local either.... try sending it to the default router */
1082                 neigh = neigh_clone(dn_db->router);
1083                 BUG_ON(neigh && neigh->dev != dev_out);
1084
1085                 /* Ok then, we assume its directly connected and move on */
1086 select_source:
1087                 if (neigh)
1088                         gateway = ((struct dn_neigh *)neigh)->addr;
1089                 if (gateway == 0)
1090                         gateway = fld.daddr;
1091                 if (fld.saddr == 0) {
1092                         fld.saddr = dnet_select_source(dev_out, gateway,
1093                                                        res.type == RTN_LOCAL ?
1094                                                        RT_SCOPE_HOST :
1095                                                        RT_SCOPE_LINK);
1096                         if (fld.saddr == 0 && res.type != RTN_LOCAL)
1097                                 goto e_addr;
1098                 }
1099                 fld.flowidn_oif = dev_out->ifindex;
1100                 goto make_route;
1101         }
1102         free_res = 1;
1103
1104         if (res.type == RTN_NAT)
1105                 goto e_inval;
1106
1107         if (res.type == RTN_LOCAL) {
1108                 if (!fld.saddr)
1109                         fld.saddr = fld.daddr;
1110                 if (dev_out)
1111                         dev_put(dev_out);
1112                 dev_out = init_net.loopback_dev;
1113                 dev_hold(dev_out);
1114                 fld.flowidn_oif = dev_out->ifindex;
1115                 if (res.fi)
1116                         dn_fib_info_put(res.fi);
1117                 res.fi = NULL;
1118                 goto make_route;
1119         }
1120
1121         if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1122                 dn_fib_select_multipath(&fld, &res);
1123
1124         /*
1125          * We could add some logic to deal with default routes here and
1126          * get rid of some of the special casing above.
1127          */
1128
1129         if (!fld.saddr)
1130                 fld.saddr = DN_FIB_RES_PREFSRC(res);
1131
1132         if (dev_out)
1133                 dev_put(dev_out);
1134         dev_out = DN_FIB_RES_DEV(res);
1135         dev_hold(dev_out);
1136         fld.flowidn_oif = dev_out->ifindex;
1137         gateway = DN_FIB_RES_GW(res);
1138
1139 make_route:
1140         if (dev_out->flags & IFF_LOOPBACK)
1141                 flags |= RTCF_LOCAL;
1142
1143         rt = dst_alloc(&dn_dst_ops, dev_out, 1, 0, DST_HOST);
1144         if (rt == NULL)
1145                 goto e_nobufs;
1146
1147         memset(&rt->fld, 0, sizeof(rt->fld));
1148         rt->fld.saddr        = oldflp->saddr;
1149         rt->fld.daddr        = oldflp->daddr;
1150         rt->fld.flowidn_oif  = oldflp->flowidn_oif;
1151         rt->fld.flowidn_iif  = 0;
1152         rt->fld.flowidn_mark = oldflp->flowidn_mark;
1153
1154         rt->rt_saddr      = fld.saddr;
1155         rt->rt_daddr      = fld.daddr;
1156         rt->rt_gateway    = gateway ? gateway : fld.daddr;
1157         rt->rt_local_src  = fld.saddr;
1158
1159         rt->rt_dst_map    = fld.daddr;
1160         rt->rt_src_map    = fld.saddr;
1161
1162         dst_set_neighbour(&rt->dst, neigh);
1163         neigh = NULL;
1164
1165         rt->dst.lastuse = jiffies;
1166         rt->dst.output  = dn_output;
1167         rt->dst.input   = dn_rt_bug;
1168         rt->rt_flags      = flags;
1169         if (flags & RTCF_LOCAL)
1170                 rt->dst.input = dn_nsp_rx;
1171
1172         err = dn_rt_set_next_hop(rt, &res);
1173         if (err)
1174                 goto e_neighbour;
1175
1176         hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1177         dn_insert_route(rt, hash, (struct dn_route **)pprt);
1178
1179 done:
1180         if (neigh)
1181                 neigh_release(neigh);
1182         if (free_res)
1183                 dn_fib_res_put(&res);
1184         if (dev_out)
1185                 dev_put(dev_out);
1186 out:
1187         return err;
1188
1189 e_addr:
1190         err = -EADDRNOTAVAIL;
1191         goto done;
1192 e_inval:
1193         err = -EINVAL;
1194         goto done;
1195 e_nobufs:
1196         err = -ENOBUFS;
1197         goto done;
1198 e_neighbour:
1199         dst_free(&rt->dst);
1200         goto e_nobufs;
1201 }
1202
1203
1204 /*
1205  * N.B. The flags may be moved into the flowi at some future stage.
1206  */
1207 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags)
1208 {
1209         unsigned int hash = dn_hash(flp->saddr, flp->daddr);
1210         struct dn_route *rt = NULL;
1211
1212         if (!(flags & MSG_TRYHARD)) {
1213                 rcu_read_lock_bh();
1214                 for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
1215                         rt = rcu_dereference_bh(rt->dst.dn_next)) {
1216                         if ((flp->daddr == rt->fld.daddr) &&
1217                             (flp->saddr == rt->fld.saddr) &&
1218                             (flp->flowidn_mark == rt->fld.flowidn_mark) &&
1219                             dn_is_output_route(rt) &&
1220                             (rt->fld.flowidn_oif == flp->flowidn_oif)) {
1221                                 dst_use(&rt->dst, jiffies);
1222                                 rcu_read_unlock_bh();
1223                                 *pprt = &rt->dst;
1224                                 return 0;
1225                         }
1226                 }
1227                 rcu_read_unlock_bh();
1228         }
1229
1230         return dn_route_output_slow(pprt, flp, flags);
1231 }
1232
1233 static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags)
1234 {
1235         int err;
1236
1237         err = __dn_route_output_key(pprt, flp, flags);
1238         if (err == 0 && flp->flowidn_proto) {
1239                 *pprt = xfrm_lookup(&init_net, *pprt,
1240                                     flowidn_to_flowi(flp), NULL, 0);
1241                 if (IS_ERR(*pprt)) {
1242                         err = PTR_ERR(*pprt);
1243                         *pprt = NULL;
1244                 }
1245         }
1246         return err;
1247 }
1248
1249 int dn_route_output_sock(struct dst_entry **pprt, struct flowidn *fl, struct sock *sk, int flags)
1250 {
1251         int err;
1252
1253         err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1254         if (err == 0 && fl->flowidn_proto) {
1255                 if (!(flags & MSG_DONTWAIT))
1256                         fl->flowidn_flags |= FLOWI_FLAG_CAN_SLEEP;
1257                 *pprt = xfrm_lookup(&init_net, *pprt,
1258                                     flowidn_to_flowi(fl), sk, 0);
1259                 if (IS_ERR(*pprt)) {
1260                         err = PTR_ERR(*pprt);
1261                         *pprt = NULL;
1262                 }
1263         }
1264         return err;
1265 }
1266
1267 static int dn_route_input_slow(struct sk_buff *skb)
1268 {
1269         struct dn_route *rt = NULL;
1270         struct dn_skb_cb *cb = DN_SKB_CB(skb);
1271         struct net_device *in_dev = skb->dev;
1272         struct net_device *out_dev = NULL;
1273         struct dn_dev *dn_db;
1274         struct neighbour *neigh = NULL;
1275         unsigned int hash;
1276         int flags = 0;
1277         __le16 gateway = 0;
1278         __le16 local_src = 0;
1279         struct flowidn fld = {
1280                 .daddr = cb->dst,
1281                 .saddr = cb->src,
1282                 .flowidn_scope = RT_SCOPE_UNIVERSE,
1283                 .flowidn_mark = skb->mark,
1284                 .flowidn_iif = skb->dev->ifindex,
1285         };
1286         struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1287         int err = -EINVAL;
1288         int free_res = 0;
1289
1290         dev_hold(in_dev);
1291
1292         if ((dn_db = rcu_dereference(in_dev->dn_ptr)) == NULL)
1293                 goto out;
1294
1295         /* Zero source addresses are not allowed */
1296         if (fld.saddr == 0)
1297                 goto out;
1298
1299         /*
1300          * In this case we've just received a packet from a source
1301          * outside ourselves pretending to come from us. We don't
1302          * allow it any further to prevent routing loops, spoofing and
1303          * other nasties. Loopback packets already have the dst attached
1304          * so this only affects packets which have originated elsewhere.
1305          */
1306         err  = -ENOTUNIQ;
1307         if (dn_dev_islocal(in_dev, cb->src))
1308                 goto out;
1309
1310         err = dn_fib_lookup(&fld, &res);
1311         if (err) {
1312                 if (err != -ESRCH)
1313                         goto out;
1314                 /*
1315                  * Is the destination us ?
1316                  */
1317                 if (!dn_dev_islocal(in_dev, cb->dst))
1318                         goto e_inval;
1319
1320                 res.type = RTN_LOCAL;
1321         } else {
1322                 __le16 src_map = fld.saddr;
1323                 free_res = 1;
1324
1325                 out_dev = DN_FIB_RES_DEV(res);
1326                 if (out_dev == NULL) {
1327                         net_crit_ratelimited("Bug in dn_route_input_slow() No output device\n");
1328                         goto e_inval;
1329                 }
1330                 dev_hold(out_dev);
1331
1332                 if (res.r)
1333                         src_map = fld.saddr; /* no NAT support for now */
1334
1335                 gateway = DN_FIB_RES_GW(res);
1336                 if (res.type == RTN_NAT) {
1337                         fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res);
1338                         dn_fib_res_put(&res);
1339                         free_res = 0;
1340                         if (dn_fib_lookup(&fld, &res))
1341                                 goto e_inval;
1342                         free_res = 1;
1343                         if (res.type != RTN_UNICAST)
1344                                 goto e_inval;
1345                         flags |= RTCF_DNAT;
1346                         gateway = fld.daddr;
1347                 }
1348                 fld.saddr = src_map;
1349         }
1350
1351         switch(res.type) {
1352         case RTN_UNICAST:
1353                 /*
1354                  * Forwarding check here, we only check for forwarding
1355                  * being turned off, if you want to only forward intra
1356                  * area, its up to you to set the routing tables up
1357                  * correctly.
1358                  */
1359                 if (dn_db->parms.forwarding == 0)
1360                         goto e_inval;
1361
1362                 if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1363                         dn_fib_select_multipath(&fld, &res);
1364
1365                 /*
1366                  * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1367                  * flag as a hint to set the intra-ethernet bit when
1368                  * forwarding. If we've got NAT in operation, we don't do
1369                  * this optimisation.
1370                  */
1371                 if (out_dev == in_dev && !(flags & RTCF_NAT))
1372                         flags |= RTCF_DOREDIRECT;
1373
1374                 local_src = DN_FIB_RES_PREFSRC(res);
1375
1376         case RTN_BLACKHOLE:
1377         case RTN_UNREACHABLE:
1378                 break;
1379         case RTN_LOCAL:
1380                 flags |= RTCF_LOCAL;
1381                 fld.saddr = cb->dst;
1382                 fld.daddr = cb->src;
1383
1384                 /* Routing tables gave us a gateway */
1385                 if (gateway)
1386                         goto make_route;
1387
1388                 /* Packet was intra-ethernet, so we know its on-link */
1389                 if (cb->rt_flags & DN_RT_F_IE) {
1390                         gateway = cb->src;
1391                         flags |= RTCF_DIRECTSRC;
1392                         goto make_route;
1393                 }
1394
1395                 /* Use the default router if there is one */
1396                 neigh = neigh_clone(dn_db->router);
1397                 if (neigh) {
1398                         gateway = ((struct dn_neigh *)neigh)->addr;
1399                         goto make_route;
1400                 }
1401
1402                 /* Close eyes and pray */
1403                 gateway = cb->src;
1404                 flags |= RTCF_DIRECTSRC;
1405                 goto make_route;
1406         default:
1407                 goto e_inval;
1408         }
1409
1410 make_route:
1411         rt = dst_alloc(&dn_dst_ops, out_dev, 0, 0, DST_HOST);
1412         if (rt == NULL)
1413                 goto e_nobufs;
1414
1415         memset(&rt->fld, 0, sizeof(rt->fld));
1416         rt->rt_saddr      = fld.saddr;
1417         rt->rt_daddr      = fld.daddr;
1418         rt->rt_gateway    = fld.daddr;
1419         if (gateway)
1420                 rt->rt_gateway = gateway;
1421         rt->rt_local_src  = local_src ? local_src : rt->rt_saddr;
1422
1423         rt->rt_dst_map    = fld.daddr;
1424         rt->rt_src_map    = fld.saddr;
1425
1426         rt->fld.saddr        = cb->src;
1427         rt->fld.daddr        = cb->dst;
1428         rt->fld.flowidn_oif  = 0;
1429         rt->fld.flowidn_iif  = in_dev->ifindex;
1430         rt->fld.flowidn_mark = fld.flowidn_mark;
1431
1432         dst_set_neighbour(&rt->dst, neigh);
1433         rt->dst.lastuse = jiffies;
1434         rt->dst.output = dn_rt_bug;
1435         switch (res.type) {
1436         case RTN_UNICAST:
1437                 rt->dst.input = dn_forward;
1438                 break;
1439         case RTN_LOCAL:
1440                 rt->dst.output = dn_output;
1441                 rt->dst.input = dn_nsp_rx;
1442                 rt->dst.dev = in_dev;
1443                 flags |= RTCF_LOCAL;
1444                 break;
1445         default:
1446         case RTN_UNREACHABLE:
1447         case RTN_BLACKHOLE:
1448                 rt->dst.input = dst_discard;
1449         }
1450         rt->rt_flags = flags;
1451
1452         err = dn_rt_set_next_hop(rt, &res);
1453         if (err)
1454                 goto e_neighbour;
1455
1456         hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1457         dn_insert_route(rt, hash, &rt);
1458         skb_dst_set(skb, &rt->dst);
1459
1460 done:
1461         if (neigh)
1462                 neigh_release(neigh);
1463         if (free_res)
1464                 dn_fib_res_put(&res);
1465         dev_put(in_dev);
1466         if (out_dev)
1467                 dev_put(out_dev);
1468 out:
1469         return err;
1470
1471 e_inval:
1472         err = -EINVAL;
1473         goto done;
1474
1475 e_nobufs:
1476         err = -ENOBUFS;
1477         goto done;
1478
1479 e_neighbour:
1480         dst_free(&rt->dst);
1481         goto done;
1482 }
1483
1484 static int dn_route_input(struct sk_buff *skb)
1485 {
1486         struct dn_route *rt;
1487         struct dn_skb_cb *cb = DN_SKB_CB(skb);
1488         unsigned int hash = dn_hash(cb->src, cb->dst);
1489
1490         if (skb_dst(skb))
1491                 return 0;
1492
1493         rcu_read_lock();
1494         for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1495             rt = rcu_dereference(rt->dst.dn_next)) {
1496                 if ((rt->fld.saddr == cb->src) &&
1497                     (rt->fld.daddr == cb->dst) &&
1498                     (rt->fld.flowidn_oif == 0) &&
1499                     (rt->fld.flowidn_mark == skb->mark) &&
1500                     (rt->fld.flowidn_iif == cb->iif)) {
1501                         dst_use(&rt->dst, jiffies);
1502                         rcu_read_unlock();
1503                         skb_dst_set(skb, (struct dst_entry *)rt);
1504                         return 0;
1505                 }
1506         }
1507         rcu_read_unlock();
1508
1509         return dn_route_input_slow(skb);
1510 }
1511
1512 static int dn_rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1513                            int event, int nowait, unsigned int flags)
1514 {
1515         struct dn_route *rt = (struct dn_route *)skb_dst(skb);
1516         struct rtmsg *r;
1517         struct nlmsghdr *nlh;
1518         unsigned char *b = skb_tail_pointer(skb);
1519         long expires;
1520
1521         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
1522         r = NLMSG_DATA(nlh);
1523         r->rtm_family = AF_DECnet;
1524         r->rtm_dst_len = 16;
1525         r->rtm_src_len = 0;
1526         r->rtm_tos = 0;
1527         r->rtm_table = RT_TABLE_MAIN;
1528         RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
1529         r->rtm_type = rt->rt_type;
1530         r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1531         r->rtm_scope = RT_SCOPE_UNIVERSE;
1532         r->rtm_protocol = RTPROT_UNSPEC;
1533         if (rt->rt_flags & RTCF_NOTIFY)
1534                 r->rtm_flags |= RTM_F_NOTIFY;
1535         RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr);
1536         if (rt->fld.saddr) {
1537                 r->rtm_src_len = 16;
1538                 RTA_PUT(skb, RTA_SRC, 2, &rt->fld.saddr);
1539         }
1540         if (rt->dst.dev)
1541                 RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->dst.dev->ifindex);
1542         /*
1543          * Note to self - change this if input routes reverse direction when
1544          * they deal only with inputs and not with replies like they do
1545          * currently.
1546          */
1547         RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src);
1548         if (rt->rt_daddr != rt->rt_gateway)
1549                 RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway);
1550         if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
1551                 goto rtattr_failure;
1552         expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
1553         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, 0, 0, expires,
1554                                rt->dst.error) < 0)
1555                 goto rtattr_failure;
1556         if (dn_is_input_route(rt))
1557                 RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fld.flowidn_iif);
1558
1559         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1560         return skb->len;
1561
1562 nlmsg_failure:
1563 rtattr_failure:
1564         nlmsg_trim(skb, b);
1565         return -1;
1566 }
1567
1568 /*
1569  * This is called by both endnodes and routers now.
1570  */
1571 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
1572 {
1573         struct net *net = sock_net(in_skb->sk);
1574         struct rtattr **rta = arg;
1575         struct rtmsg *rtm = NLMSG_DATA(nlh);
1576         struct dn_route *rt = NULL;
1577         struct dn_skb_cb *cb;
1578         int err;
1579         struct sk_buff *skb;
1580         struct flowidn fld;
1581
1582         if (!net_eq(net, &init_net))
1583                 return -EINVAL;
1584
1585         memset(&fld, 0, sizeof(fld));
1586         fld.flowidn_proto = DNPROTO_NSP;
1587
1588         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1589         if (skb == NULL)
1590                 return -ENOBUFS;
1591         skb_reset_mac_header(skb);
1592         cb = DN_SKB_CB(skb);
1593
1594         if (rta[RTA_SRC-1])
1595                 memcpy(&fld.saddr, RTA_DATA(rta[RTA_SRC-1]), 2);
1596         if (rta[RTA_DST-1])
1597                 memcpy(&fld.daddr, RTA_DATA(rta[RTA_DST-1]), 2);
1598         if (rta[RTA_IIF-1])
1599                 memcpy(&fld.flowidn_iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
1600
1601         if (fld.flowidn_iif) {
1602                 struct net_device *dev;
1603                 if ((dev = dev_get_by_index(&init_net, fld.flowidn_iif)) == NULL) {
1604                         kfree_skb(skb);
1605                         return -ENODEV;
1606                 }
1607                 if (!dev->dn_ptr) {
1608                         dev_put(dev);
1609                         kfree_skb(skb);
1610                         return -ENODEV;
1611                 }
1612                 skb->protocol = htons(ETH_P_DNA_RT);
1613                 skb->dev = dev;
1614                 cb->src = fld.saddr;
1615                 cb->dst = fld.daddr;
1616                 local_bh_disable();
1617                 err = dn_route_input(skb);
1618                 local_bh_enable();
1619                 memset(cb, 0, sizeof(struct dn_skb_cb));
1620                 rt = (struct dn_route *)skb_dst(skb);
1621                 if (!err && -rt->dst.error)
1622                         err = rt->dst.error;
1623         } else {
1624                 int oif = 0;
1625                 if (rta[RTA_OIF - 1])
1626                         memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
1627                 fld.flowidn_oif = oif;
1628                 err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
1629         }
1630
1631         if (skb->dev)
1632                 dev_put(skb->dev);
1633         skb->dev = NULL;
1634         if (err)
1635                 goto out_free;
1636         skb_dst_set(skb, &rt->dst);
1637         if (rtm->rtm_flags & RTM_F_NOTIFY)
1638                 rt->rt_flags |= RTCF_NOTIFY;
1639
1640         err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1641
1642         if (err == 0)
1643                 goto out_free;
1644         if (err < 0) {
1645                 err = -EMSGSIZE;
1646                 goto out_free;
1647         }
1648
1649         return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).pid);
1650
1651 out_free:
1652         kfree_skb(skb);
1653         return err;
1654 }
1655
1656 /*
1657  * For routers, this is called from dn_fib_dump, but for endnodes its
1658  * called directly from the rtnetlink dispatch table.
1659  */
1660 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1661 {
1662         struct net *net = sock_net(skb->sk);
1663         struct dn_route *rt;
1664         int h, s_h;
1665         int idx, s_idx;
1666
1667         if (!net_eq(net, &init_net))
1668                 return 0;
1669
1670         if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg))
1671                 return -EINVAL;
1672         if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED))
1673                 return 0;
1674
1675         s_h = cb->args[0];
1676         s_idx = idx = cb->args[1];
1677         for(h = 0; h <= dn_rt_hash_mask; h++) {
1678                 if (h < s_h)
1679                         continue;
1680                 if (h > s_h)
1681                         s_idx = 0;
1682                 rcu_read_lock_bh();
1683                 for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
1684                         rt;
1685                         rt = rcu_dereference_bh(rt->dst.dn_next), idx++) {
1686                         if (idx < s_idx)
1687                                 continue;
1688                         skb_dst_set(skb, dst_clone(&rt->dst));
1689                         if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
1690                                         cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1691                                         1, NLM_F_MULTI) <= 0) {
1692                                 skb_dst_drop(skb);
1693                                 rcu_read_unlock_bh();
1694                                 goto done;
1695                         }
1696                         skb_dst_drop(skb);
1697                 }
1698                 rcu_read_unlock_bh();
1699         }
1700
1701 done:
1702         cb->args[0] = h;
1703         cb->args[1] = idx;
1704         return skb->len;
1705 }
1706
1707 #ifdef CONFIG_PROC_FS
1708 struct dn_rt_cache_iter_state {
1709         int bucket;
1710 };
1711
1712 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1713 {
1714         struct dn_route *rt = NULL;
1715         struct dn_rt_cache_iter_state *s = seq->private;
1716
1717         for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1718                 rcu_read_lock_bh();
1719                 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1720                 if (rt)
1721                         break;
1722                 rcu_read_unlock_bh();
1723         }
1724         return rt;
1725 }
1726
1727 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1728 {
1729         struct dn_rt_cache_iter_state *s = seq->private;
1730
1731         rt = rcu_dereference_bh(rt->dst.dn_next);
1732         while (!rt) {
1733                 rcu_read_unlock_bh();
1734                 if (--s->bucket < 0)
1735                         break;
1736                 rcu_read_lock_bh();
1737                 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1738         }
1739         return rt;
1740 }
1741
1742 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1743 {
1744         struct dn_route *rt = dn_rt_cache_get_first(seq);
1745
1746         if (rt) {
1747                 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1748                         --*pos;
1749         }
1750         return *pos ? NULL : rt;
1751 }
1752
1753 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1754 {
1755         struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1756         ++*pos;
1757         return rt;
1758 }
1759
1760 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1761 {
1762         if (v)
1763                 rcu_read_unlock_bh();
1764 }
1765
1766 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1767 {
1768         struct dn_route *rt = v;
1769         char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1770
1771         seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1772                         rt->dst.dev ? rt->dst.dev->name : "*",
1773                         dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
1774                         dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
1775                         atomic_read(&rt->dst.__refcnt),
1776                         rt->dst.__use,
1777                         (int) dst_metric(&rt->dst, RTAX_RTT));
1778         return 0;
1779 }
1780
1781 static const struct seq_operations dn_rt_cache_seq_ops = {
1782         .start  = dn_rt_cache_seq_start,
1783         .next   = dn_rt_cache_seq_next,
1784         .stop   = dn_rt_cache_seq_stop,
1785         .show   = dn_rt_cache_seq_show,
1786 };
1787
1788 static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1789 {
1790         return seq_open_private(file, &dn_rt_cache_seq_ops,
1791                         sizeof(struct dn_rt_cache_iter_state));
1792 }
1793
1794 static const struct file_operations dn_rt_cache_seq_fops = {
1795         .owner   = THIS_MODULE,
1796         .open    = dn_rt_cache_seq_open,
1797         .read    = seq_read,
1798         .llseek  = seq_lseek,
1799         .release = seq_release_private,
1800 };
1801
1802 #endif /* CONFIG_PROC_FS */
1803
1804 void __init dn_route_init(void)
1805 {
1806         int i, goal, order;
1807
1808         dn_dst_ops.kmem_cachep =
1809                 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1810                                   SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1811         dst_entries_init(&dn_dst_ops);
1812         setup_timer(&dn_route_timer, dn_dst_check_expire, 0);
1813         dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1814         add_timer(&dn_route_timer);
1815
1816         goal = totalram_pages >> (26 - PAGE_SHIFT);
1817
1818         for(order = 0; (1UL << order) < goal; order++)
1819                 /* NOTHING */;
1820
1821         /*
1822          * Only want 1024 entries max, since the table is very, very unlikely
1823          * to be larger than that.
1824          */
1825         while(order && ((((1UL << order) * PAGE_SIZE) /
1826                                 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1827                 order--;
1828
1829         do {
1830                 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1831                         sizeof(struct dn_rt_hash_bucket);
1832                 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1833                         dn_rt_hash_mask--;
1834                 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1835                         __get_free_pages(GFP_ATOMIC, order);
1836         } while (dn_rt_hash_table == NULL && --order > 0);
1837
1838         if (!dn_rt_hash_table)
1839                 panic("Failed to allocate DECnet route cache hash table\n");
1840
1841         printk(KERN_INFO
1842                 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1843                 dn_rt_hash_mask,
1844                 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1845
1846         dn_rt_hash_mask--;
1847         for(i = 0; i <= dn_rt_hash_mask; i++) {
1848                 spin_lock_init(&dn_rt_hash_table[i].lock);
1849                 dn_rt_hash_table[i].chain = NULL;
1850         }
1851
1852         dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1853
1854         proc_net_fops_create(&init_net, "decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
1855
1856 #ifdef CONFIG_DECNET_ROUTER
1857         rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1858                       dn_fib_dump, NULL);
1859 #else
1860         rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1861                       dn_cache_dump, NULL);
1862 #endif
1863 }
1864
1865 void __exit dn_route_cleanup(void)
1866 {
1867         del_timer(&dn_route_timer);
1868         dn_run_flush(0);
1869
1870         proc_net_remove(&init_net, "decnet_cache");
1871         dst_entries_destroy(&dn_dst_ops);
1872 }
1873