linux/net/decnet/dn_route.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * DECnet       An implementation of the DECnet protocol suite for the LINUX
   4 *              operating system.  DECnet is implemented using the  BSD Socket
   5 *              interface as the means of communication with the user level.
   6 *
   7 *              DECnet Routing Functions (Endnode and Router)
   8 *
   9 * Authors:     Steve Whitehouse <SteveW@ACM.org>
  10 *              Eduardo Marcelo Serrat <emserrat@geocities.com>
  11 *
  12 * Changes:
  13 *              Steve Whitehouse : Fixes to allow "intra-ethernet" and
  14 *                                 "return-to-sender" bits on outgoing
  15 *                                 packets.
  16 *              Steve Whitehouse : Timeouts for cached routes.
  17 *              Steve Whitehouse : Use dst cache for input routes too.
  18 *              Steve Whitehouse : Fixed error values in dn_send_skb.
  19 *              Steve Whitehouse : Rework routing functions to better fit
  20 *                                 DECnet routing design
  21 *              Alexey Kuznetsov : New SMP locking
  22 *              Steve Whitehouse : More SMP locking changes & dn_cache_dump()
  23 *              Steve Whitehouse : Prerouting NF hook, now really is prerouting.
  24 *                                 Fixed possible skb leak in rtnetlink funcs.
  25 *              Steve Whitehouse : Dave Miller's dynamic hash table sizing and
  26 *                                 Alexey Kuznetsov's finer grained locking
  27 *                                 from ipv4/route.c.
  28 *              Steve Whitehouse : Routing is now starting to look like a
  29 *                                 sensible set of code now, mainly due to
  30 *                                 my copying the IPv4 routing code. The
  31 *                                 hooks here are modified and will continue
  32 *                                 to evolve for a while.
  33 *              Steve Whitehouse : Real SMP at last :-) Also new netfilter
  34 *                                 stuff. Look out raw sockets your days
  35 *                                 are numbered!
  36 *              Steve Whitehouse : Added return-to-sender functions. Added
  37 *                                 backlog congestion level return codes.
  38 *              Steve Whitehouse : Fixed bug where routes were set up with
  39 *                                 no ref count on net devices.
  40 *              Steve Whitehouse : RCU for the route cache
  41 *              Steve Whitehouse : Preparations for the flow cache
  42 *              Steve Whitehouse : Prepare for nonlinear skbs
  43 */
  44
  45/******************************************************************************
  46    (c) 1995-1998 E.M. Serrat           emserrat@geocities.com
  47
  48*******************************************************************************/
  49
  50#include <linux/errno.h>
  51#include <linux/types.h>
  52#include <linux/socket.h>
  53#include <linux/in.h>
  54#include <linux/kernel.h>
  55#include <linux/sockios.h>
  56#include <linux/net.h>
  57#include <linux/netdevice.h>
  58#include <linux/inet.h>
  59#include <linux/route.h>
  60#include <linux/in_route.h>
  61#include <linux/slab.h>
  62#include <net/sock.h>
  63#include <linux/mm.h>
  64#include <linux/proc_fs.h>
  65#include <linux/seq_file.h>
  66#include <linux/init.h>
  67#include <linux/rtnetlink.h>
  68#include <linux/string.h>
  69#include <linux/netfilter_decnet.h>
  70#include <linux/rcupdate.h>
  71#include <linux/times.h>
  72#include <linux/export.h>
  73#include <asm/errno.h>
  74#include <net/net_namespace.h>
  75#include <net/netlink.h>
  76#include <net/neighbour.h>
  77#include <net/dst.h>
  78#include <net/flow.h>
  79#include <net/fib_rules.h>
  80#include <net/dn.h>
  81#include <net/dn_dev.h>
  82#include <net/dn_nsp.h>
  83#include <net/dn_route.h>
  84#include <net/dn_neigh.h>
  85#include <net/dn_fib.h>
  86
  87struct dn_rt_hash_bucket
  88{
  89        struct dn_route __rcu *chain;
  90        spinlock_t lock;
  91};
  92
  93extern struct neigh_table dn_neigh_table;
  94
  95
  96static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
  97
  98static const int dn_rt_min_delay = 2 * HZ;
  99static const int dn_rt_max_delay = 10 * HZ;
 100static const int dn_rt_mtu_expires = 10 * 60 * HZ;
 101
 102static unsigned long dn_rt_deadline;
 103
 104static int dn_dst_gc(struct dst_ops *ops);
 105static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
 106static unsigned int dn_dst_default_advmss(const struct dst_entry *dst);
 107static unsigned int dn_dst_mtu(const struct dst_entry *dst);
 108static void dn_dst_destroy(struct dst_entry *);
 109static void dn_dst_ifdown(struct dst_entry *, struct net_device *dev, int how);
 110static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
 111static void dn_dst_link_failure(struct sk_buff *);
 112static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
 113                               struct sk_buff *skb , u32 mtu);
 114static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
 115                            struct sk_buff *skb);
 116static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
 117                                             struct sk_buff *skb,
 118                                             const void *daddr);
 119static int dn_route_input(struct sk_buff *);
 120static void dn_run_flush(struct timer_list *unused);
 121
 122static struct dn_rt_hash_bucket *dn_rt_hash_table;
 123static unsigned int dn_rt_hash_mask;
 124
 125static struct timer_list dn_route_timer;
 126static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush);
 127int decnet_dst_gc_interval = 2;
 128
 129static struct dst_ops dn_dst_ops = {
 130        .family =               PF_DECnet,
 131        .gc_thresh =            128,
 132        .gc =                   dn_dst_gc,
 133        .check =                dn_dst_check,
 134        .default_advmss =       dn_dst_default_advmss,
 135        .mtu =                  dn_dst_mtu,
 136        .cow_metrics =          dst_cow_metrics_generic,
 137        .destroy =              dn_dst_destroy,
 138        .ifdown =               dn_dst_ifdown,
 139        .negative_advice =      dn_dst_negative_advice,
 140        .link_failure =         dn_dst_link_failure,
 141        .update_pmtu =          dn_dst_update_pmtu,
 142        .redirect =             dn_dst_redirect,
 143        .neigh_lookup =         dn_dst_neigh_lookup,
 144};
 145
 146static void dn_dst_destroy(struct dst_entry *dst)
 147{
 148        struct dn_route *rt = (struct dn_route *) dst;
 149
 150        if (rt->n)
 151                neigh_release(rt->n);
 152        dst_destroy_metrics_generic(dst);
 153}
 154
 155static void dn_dst_ifdown(struct dst_entry *dst, struct net_device *dev, int how)
 156{
 157        if (how) {
 158                struct dn_route *rt = (struct dn_route *) dst;
 159                struct neighbour *n = rt->n;
 160
 161                if (n && n->dev == dev) {
 162                        n->dev = dev_net(dev)->loopback_dev;
 163                        dev_hold(n->dev);
 164                        dev_put(dev);
 165                }
 166        }
 167}
 168
 169static __inline__ unsigned int dn_hash(__le16 src, __le16 dst)
 170{
 171        __u16 tmp = (__u16 __force)(src ^ dst);
 172        tmp ^= (tmp >> 3);
 173        tmp ^= (tmp >> 5);
 174        tmp ^= (tmp >> 10);
 175        return dn_rt_hash_mask & (unsigned int)tmp;
 176}
 177
 178static void dn_dst_check_expire(struct timer_list *unused)
 179{
 180        int i;
 181        struct dn_route *rt;
 182        struct dn_route __rcu **rtp;
 183        unsigned long now = jiffies;
 184        unsigned long expire = 120 * HZ;
 185
 186        for (i = 0; i <= dn_rt_hash_mask; i++) {
 187                rtp = &dn_rt_hash_table[i].chain;
 188
 189                spin_lock(&dn_rt_hash_table[i].lock);
 190                while ((rt = rcu_dereference_protected(*rtp,
 191                                                lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
 192                        if (atomic_read(&rt->dst.__refcnt) > 1 ||
 193                            (now - rt->dst.lastuse) < expire) {
 194                                rtp = &rt->dn_next;
 195                                continue;
 196                        }
 197                        *rtp = rt->dn_next;
 198                        rt->dn_next = NULL;
 199                        dst_dev_put(&rt->dst);
 200                        dst_release(&rt->dst);
 201                }
 202                spin_unlock(&dn_rt_hash_table[i].lock);
 203
 204                if ((jiffies - now) > 0)
 205                        break;
 206        }
 207
 208        mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ);
 209}
 210
 211static int dn_dst_gc(struct dst_ops *ops)
 212{
 213        struct dn_route *rt;
 214        struct dn_route __rcu **rtp;
 215        int i;
 216        unsigned long now = jiffies;
 217        unsigned long expire = 10 * HZ;
 218
 219        for (i = 0; i <= dn_rt_hash_mask; i++) {
 220
 221                spin_lock_bh(&dn_rt_hash_table[i].lock);
 222                rtp = &dn_rt_hash_table[i].chain;
 223
 224                while ((rt = rcu_dereference_protected(*rtp,
 225                                                lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
 226                        if (atomic_read(&rt->dst.__refcnt) > 1 ||
 227                            (now - rt->dst.lastuse) < expire) {
 228                                rtp = &rt->dn_next;
 229                                continue;
 230                        }
 231                        *rtp = rt->dn_next;
 232                        rt->dn_next = NULL;
 233                        dst_dev_put(&rt->dst);
 234                        dst_release(&rt->dst);
 235                        break;
 236                }
 237                spin_unlock_bh(&dn_rt_hash_table[i].lock);
 238        }
 239
 240        return 0;
 241}
 242
 243/*
 244 * The decnet standards don't impose a particular minimum mtu, what they
 245 * do insist on is that the routing layer accepts a datagram of at least
 246 * 230 bytes long. Here we have to subtract the routing header length from
 247 * 230 to get the minimum acceptable mtu. If there is no neighbour, then we
 248 * assume the worst and use a long header size.
 249 *
 250 * We update both the mtu and the advertised mss (i.e. the segment size we
 251 * advertise to the other end).
 252 */
 253static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
 254                               struct sk_buff *skb, u32 mtu)
 255{
 256        struct dn_route *rt = (struct dn_route *) dst;
 257        struct neighbour *n = rt->n;
 258        u32 min_mtu = 230;
 259        struct dn_dev *dn;
 260
 261        dn = n ? rcu_dereference_raw(n->dev->dn_ptr) : NULL;
 262
 263        if (dn && dn->use_long == 0)
 264                min_mtu -= 6;
 265        else
 266                min_mtu -= 21;
 267
 268        if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= min_mtu) {
 269                if (!(dst_metric_locked(dst, RTAX_MTU))) {
 270                        dst_metric_set(dst, RTAX_MTU, mtu);
 271                        dst_set_expires(dst, dn_rt_mtu_expires);
 272                }
 273                if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
 274                        u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
 275                        u32 existing_mss = dst_metric_raw(dst, RTAX_ADVMSS);
 276                        if (!existing_mss || existing_mss > mss)
 277                                dst_metric_set(dst, RTAX_ADVMSS, mss);
 278                }
 279        }
 280}
 281
 282static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
 283                            struct sk_buff *skb)
 284{
 285}
 286
 287/*
 288 * When a route has been marked obsolete. (e.g. routing cache flush)
 289 */
 290static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
 291{
 292        return NULL;
 293}
 294
 295static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
 296{
 297        dst_release(dst);
 298        return NULL;
 299}
 300
 301static void dn_dst_link_failure(struct sk_buff *skb)
 302{
 303}
 304
 305static inline int compare_keys(struct flowidn *fl1, struct flowidn *fl2)
 306{
 307        return ((fl1->daddr ^ fl2->daddr) |
 308                (fl1->saddr ^ fl2->saddr) |
 309                (fl1->flowidn_mark ^ fl2->flowidn_mark) |
 310                (fl1->flowidn_scope ^ fl2->flowidn_scope) |
 311                (fl1->flowidn_oif ^ fl2->flowidn_oif) |
 312                (fl1->flowidn_iif ^ fl2->flowidn_iif)) == 0;
 313}
 314
 315static int dn_insert_route(struct dn_route *rt, unsigned int hash, struct dn_route **rp)
 316{
 317        struct dn_route *rth;
 318        struct dn_route __rcu **rthp;
 319        unsigned long now = jiffies;
 320
 321        rthp = &dn_rt_hash_table[hash].chain;
 322
 323        spin_lock_bh(&dn_rt_hash_table[hash].lock);
 324        while ((rth = rcu_dereference_protected(*rthp,
 325                                                lockdep_is_held(&dn_rt_hash_table[hash].lock))) != NULL) {
 326                if (compare_keys(&rth->fld, &rt->fld)) {
 327                        /* Put it first */
 328                        *rthp = rth->dn_next;
 329                        rcu_assign_pointer(rth->dn_next,
 330                                           dn_rt_hash_table[hash].chain);
 331                        rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
 332
 333                        dst_hold_and_use(&rth->dst, now);
 334                        spin_unlock_bh(&dn_rt_hash_table[hash].lock);
 335
 336                        dst_release_immediate(&rt->dst);
 337                        *rp = rth;
 338                        return 0;
 339                }
 340                rthp = &rth->dn_next;
 341        }
 342
 343        rcu_assign_pointer(rt->dn_next, dn_rt_hash_table[hash].chain);
 344        rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
 345
 346        dst_hold_and_use(&rt->dst, now);
 347        spin_unlock_bh(&dn_rt_hash_table[hash].lock);
 348        *rp = rt;
 349        return 0;
 350}
 351
 352static void dn_run_flush(struct timer_list *unused)
 353{
 354        int i;
 355        struct dn_route *rt, *next;
 356
 357        for (i = 0; i < dn_rt_hash_mask; i++) {
 358                spin_lock_bh(&dn_rt_hash_table[i].lock);
 359
 360                if ((rt = xchg((struct dn_route **)&dn_rt_hash_table[i].chain, NULL)) == NULL)
 361                        goto nothing_to_declare;
 362
 363                for(; rt; rt = next) {
 364                        next = rcu_dereference_raw(rt->dn_next);
 365                        RCU_INIT_POINTER(rt->dn_next, NULL);
 366                        dst_dev_put(&rt->dst);
 367                        dst_release(&rt->dst);
 368                }
 369
 370nothing_to_declare:
 371                spin_unlock_bh(&dn_rt_hash_table[i].lock);
 372        }
 373}
 374
 375static DEFINE_SPINLOCK(dn_rt_flush_lock);
 376
 377void dn_rt_cache_flush(int delay)
 378{
 379        unsigned long now = jiffies;
 380        int user_mode = !in_interrupt();
 381
 382        if (delay < 0)
 383                delay = dn_rt_min_delay;
 384
 385        spin_lock_bh(&dn_rt_flush_lock);
 386
 387        if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
 388                long tmo = (long)(dn_rt_deadline - now);
 389
 390                if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
 391                        tmo = 0;
 392
 393                if (delay > tmo)
 394                        delay = tmo;
 395        }
 396
 397        if (delay <= 0) {
 398                spin_unlock_bh(&dn_rt_flush_lock);
 399                dn_run_flush(NULL);
 400                return;
 401        }
 402
 403        if (dn_rt_deadline == 0)
 404                dn_rt_deadline = now + dn_rt_max_delay;
 405
 406        dn_rt_flush_timer.expires = now + delay;
 407        add_timer(&dn_rt_flush_timer);
 408        spin_unlock_bh(&dn_rt_flush_lock);
 409}
 410
 411/**
 412 * dn_return_short - Return a short packet to its sender
 413 * @skb: The packet to return
 414 *
 415 */
 416static int dn_return_short(struct sk_buff *skb)
 417{
 418        struct dn_skb_cb *cb;
 419        unsigned char *ptr;
 420        __le16 *src;
 421        __le16 *dst;
 422
 423        /* Add back headers */
 424        skb_push(skb, skb->data - skb_network_header(skb));
 425
 426        if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
 427                return NET_RX_DROP;
 428
 429        cb = DN_SKB_CB(skb);
 430        /* Skip packet length and point to flags */
 431        ptr = skb->data + 2;
 432        *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
 433
 434        dst = (__le16 *)ptr;
 435        ptr += 2;
 436        src = (__le16 *)ptr;
 437        ptr += 2;
 438        *ptr = 0; /* Zero hop count */
 439
 440        swap(*src, *dst);
 441
 442        skb->pkt_type = PACKET_OUTGOING;
 443        dn_rt_finish_output(skb, NULL, NULL);
 444        return NET_RX_SUCCESS;
 445}
 446
 447/**
 448 * dn_return_long - Return a long packet to its sender
 449 * @skb: The long format packet to return
 450 *
 451 */
 452static int dn_return_long(struct sk_buff *skb)
 453{
 454        struct dn_skb_cb *cb;
 455        unsigned char *ptr;
 456        unsigned char *src_addr, *dst_addr;
 457        unsigned char tmp[ETH_ALEN];
 458
 459        /* Add back all headers */
 460        skb_push(skb, skb->data - skb_network_header(skb));
 461
 462        if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
 463                return NET_RX_DROP;
 464
 465        cb = DN_SKB_CB(skb);
 466        /* Ignore packet length and point to flags */
 467        ptr = skb->data + 2;
 468
 469        /* Skip padding */
 470        if (*ptr & DN_RT_F_PF) {
 471                char padlen = (*ptr & ~DN_RT_F_PF);
 472                ptr += padlen;
 473        }
 474
 475        *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
 476        ptr += 2;
 477        dst_addr = ptr;
 478        ptr += 8;
 479        src_addr = ptr;
 480        ptr += 6;
 481        *ptr = 0; /* Zero hop count */
 482
 483        /* Swap source and destination */
 484        memcpy(tmp, src_addr, ETH_ALEN);
 485        memcpy(src_addr, dst_addr, ETH_ALEN);
 486        memcpy(dst_addr, tmp, ETH_ALEN);
 487
 488        skb->pkt_type = PACKET_OUTGOING;
 489        dn_rt_finish_output(skb, dst_addr, src_addr);
 490        return NET_RX_SUCCESS;
 491}
 492
 493/**
 494 * dn_route_rx_packet - Try and find a route for an incoming packet
 495 * @skb: The packet to find a route for
 496 *
 497 * Returns: result of input function if route is found, error code otherwise
 498 */
 499static int dn_route_rx_packet(struct net *net, struct sock *sk, struct sk_buff *skb)
 500{
 501        struct dn_skb_cb *cb;
 502        int err;
 503
 504        if ((err = dn_route_input(skb)) == 0)
 505                return dst_input(skb);
 506
 507        cb = DN_SKB_CB(skb);
 508        if (decnet_debug_level & 4) {
 509                char *devname = skb->dev ? skb->dev->name : "???";
 510
 511                printk(KERN_DEBUG
 512                        "DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
 513                        (int)cb->rt_flags, devname, skb->len,
 514                        le16_to_cpu(cb->src), le16_to_cpu(cb->dst),
 515                        err, skb->pkt_type);
 516        }
 517
 518        if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
 519                switch (cb->rt_flags & DN_RT_PKT_MSK) {
 520                case DN_RT_PKT_SHORT:
 521                        return dn_return_short(skb);
 522                case DN_RT_PKT_LONG:
 523                        return dn_return_long(skb);
 524                }
 525        }
 526
 527        kfree_skb(skb);
 528        return NET_RX_DROP;
 529}
 530
 531static int dn_route_rx_long(struct sk_buff *skb)
 532{
 533        struct dn_skb_cb *cb = DN_SKB_CB(skb);
 534        unsigned char *ptr = skb->data;
 535
 536        if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
 537                goto drop_it;
 538
 539        skb_pull(skb, 20);
 540        skb_reset_transport_header(skb);
 541
 542        /* Destination info */
 543        ptr += 2;
 544        cb->dst = dn_eth2dn(ptr);
 545        if (memcmp(ptr, dn_hiord_addr, 4) != 0)
 546                goto drop_it;
 547        ptr += 6;
 548
 549
 550        /* Source info */
 551        ptr += 2;
 552        cb->src = dn_eth2dn(ptr);
 553        if (memcmp(ptr, dn_hiord_addr, 4) != 0)
 554                goto drop_it;
 555        ptr += 6;
 556        /* Other junk */
 557        ptr++;
 558        cb->hops = *ptr++; /* Visit Count */
 559
 560        return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
 561                       &init_net, NULL, skb, skb->dev, NULL,
 562                       dn_route_rx_packet);
 563
 564drop_it:
 565        kfree_skb(skb);
 566        return NET_RX_DROP;
 567}
 568
 569
 570
 571static int dn_route_rx_short(struct sk_buff *skb)
 572{
 573        struct dn_skb_cb *cb = DN_SKB_CB(skb);
 574        unsigned char *ptr = skb->data;
 575
 576        if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
 577                goto drop_it;
 578
 579        skb_pull(skb, 5);
 580        skb_reset_transport_header(skb);
 581
 582        cb->dst = *(__le16 *)ptr;
 583        ptr += 2;
 584        cb->src = *(__le16 *)ptr;
 585        ptr += 2;
 586        cb->hops = *ptr & 0x3f;
 587
 588        return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
 589                       &init_net, NULL, skb, skb->dev, NULL,
 590                       dn_route_rx_packet);
 591
 592drop_it:
 593        kfree_skb(skb);
 594        return NET_RX_DROP;
 595}
 596
 597static int dn_route_discard(struct net *net, struct sock *sk, struct sk_buff *skb)
 598{
 599        /*
 600         * I know we drop the packet here, but thats considered success in
 601         * this case
 602         */
 603        kfree_skb(skb);
 604        return NET_RX_SUCCESS;
 605}
 606
 607static int dn_route_ptp_hello(struct net *net, struct sock *sk, struct sk_buff *skb)
 608{
 609        dn_dev_hello(skb);
 610        dn_neigh_pointopoint_hello(skb);
 611        return NET_RX_SUCCESS;
 612}
 613
 614int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 615{
 616        struct dn_skb_cb *cb;
 617        unsigned char flags = 0;
 618        __u16 len = le16_to_cpu(*(__le16 *)skb->data);
 619        struct dn_dev *dn = rcu_dereference(dev->dn_ptr);
 620        unsigned char padlen = 0;
 621
 622        if (!net_eq(dev_net(dev), &init_net))
 623                goto dump_it;
 624
 625        if (dn == NULL)
 626                goto dump_it;
 627
 628        if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 629                goto out;
 630
 631        if (!pskb_may_pull(skb, 3))
 632                goto dump_it;
 633
 634        skb_pull(skb, 2);
 635
 636        if (len > skb->len)
 637                goto dump_it;
 638
 639        skb_trim(skb, len);
 640
 641        flags = *skb->data;
 642
 643        cb = DN_SKB_CB(skb);
 644        cb->stamp = jiffies;
 645        cb->iif = dev->ifindex;
 646
 647        /*
 648         * If we have padding, remove it.
 649         */
 650        if (flags & DN_RT_F_PF) {
 651                padlen = flags & ~DN_RT_F_PF;
 652                if (!pskb_may_pull(skb, padlen + 1))
 653                        goto dump_it;
 654                skb_pull(skb, padlen);
 655                flags = *skb->data;
 656        }
 657
 658        skb_reset_network_header(skb);
 659
 660        /*
 661         * Weed out future version DECnet
 662         */
 663        if (flags & DN_RT_F_VER)
 664                goto dump_it;
 665
 666        cb->rt_flags = flags;
 667
 668        if (decnet_debug_level & 1)
 669                printk(KERN_DEBUG
 670                        "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
 671                        (int)flags, (dev) ? dev->name : "???", len, skb->len,
 672                        padlen);
 673
 674        if (flags & DN_RT_PKT_CNTL) {
 675                if (unlikely(skb_linearize(skb)))
 676                        goto dump_it;
 677
 678                switch (flags & DN_RT_CNTL_MSK) {
 679                case DN_RT_PKT_INIT:
 680                        dn_dev_init_pkt(skb);
 681                        break;
 682                case DN_RT_PKT_VERI:
 683                        dn_dev_veri_pkt(skb);
 684                        break;
 685                }
 686
 687                if (dn->parms.state != DN_DEV_S_RU)
 688                        goto dump_it;
 689
 690                switch (flags & DN_RT_CNTL_MSK) {
 691                case DN_RT_PKT_HELO:
 692                        return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 693                                       &init_net, NULL, skb, skb->dev, NULL,
 694                                       dn_route_ptp_hello);
 695
 696                case DN_RT_PKT_L1RT:
 697                case DN_RT_PKT_L2RT:
 698                        return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE,
 699                                       &init_net, NULL, skb, skb->dev, NULL,
 700                                       dn_route_discard);
 701                case DN_RT_PKT_ERTH:
 702                        return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 703                                       &init_net, NULL, skb, skb->dev, NULL,
 704                                       dn_neigh_router_hello);
 705
 706                case DN_RT_PKT_EEDH:
 707                        return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 708                                       &init_net, NULL, skb, skb->dev, NULL,
 709                                       dn_neigh_endnode_hello);
 710                }
 711        } else {
 712                if (dn->parms.state != DN_DEV_S_RU)
 713                        goto dump_it;
 714
 715                skb_pull(skb, 1); /* Pull flags */
 716
 717                switch (flags & DN_RT_PKT_MSK) {
 718                case DN_RT_PKT_LONG:
 719                        return dn_route_rx_long(skb);
 720                case DN_RT_PKT_SHORT:
 721                        return dn_route_rx_short(skb);
 722                }
 723        }
 724
 725dump_it:
 726        kfree_skb(skb);
 727out:
 728        return NET_RX_DROP;
 729}
 730
 731static int dn_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 732{
 733        struct dst_entry *dst = skb_dst(skb);
 734        struct dn_route *rt = (struct dn_route *)dst;
 735        struct net_device *dev = dst->dev;
 736        struct dn_skb_cb *cb = DN_SKB_CB(skb);
 737
 738        int err = -EINVAL;
 739
 740        if (rt->n == NULL)
 741                goto error;
 742
 743        skb->dev = dev;
 744
 745        cb->src = rt->rt_saddr;
 746        cb->dst = rt->rt_daddr;
 747
 748        /*
 749         * Always set the Intra-Ethernet bit on all outgoing packets
 750         * originated on this node. Only valid flag from upper layers
 751         * is return-to-sender-requested. Set hop count to 0 too.
 752         */
 753        cb->rt_flags &= ~DN_RT_F_RQR;
 754        cb->rt_flags |= DN_RT_F_IE;
 755        cb->hops = 0;
 756
 757        return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT,
 758                       &init_net, sk, skb, NULL, dev,
 759                       dn_to_neigh_output);
 760
 761error:
 762        net_dbg_ratelimited("dn_output: This should not happen\n");
 763
 764        kfree_skb(skb);
 765
 766        return err;
 767}
 768
 769static int dn_forward(struct sk_buff *skb)
 770{
 771        struct dn_skb_cb *cb = DN_SKB_CB(skb);
 772        struct dst_entry *dst = skb_dst(skb);
 773        struct dn_dev *dn_db = rcu_dereference(dst->dev->dn_ptr);
 774        struct dn_route *rt;
 775        int header_len;
 776        struct net_device *dev = skb->dev;
 777
 778        if (skb->pkt_type != PACKET_HOST)
 779                goto drop;
 780
 781        /* Ensure that we have enough space for headers */
 782        rt = (struct dn_route *)skb_dst(skb);
 783        header_len = dn_db->use_long ? 21 : 6;
 784        if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+header_len))
 785                goto drop;
 786
 787        /*
 788         * Hop count exceeded.
 789         */
 790        if (++cb->hops > 30)
 791                goto drop;
 792
 793        skb->dev = rt->dst.dev;
 794
 795        /*
 796         * If packet goes out same interface it came in on, then set
 797         * the Intra-Ethernet bit. This has no effect for short
 798         * packets, so we don't need to test for them here.
 799         */
 800        cb->rt_flags &= ~DN_RT_F_IE;
 801        if (rt->rt_flags & RTCF_DOREDIRECT)
 802                cb->rt_flags |= DN_RT_F_IE;
 803
 804        return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD,
 805                       &init_net, NULL, skb, dev, skb->dev,
 806                       dn_to_neigh_output);
 807
 808drop:
 809        kfree_skb(skb);
 810        return NET_RX_DROP;
 811}
 812
 813/*
 814 * Used to catch bugs. This should never normally get
 815 * called.
 816 */
 817static int dn_rt_bug_out(struct net *net, struct sock *sk, struct sk_buff *skb)
 818{
 819        struct dn_skb_cb *cb = DN_SKB_CB(skb);
 820
 821        net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
 822                            le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
 823
 824        kfree_skb(skb);
 825
 826        return NET_RX_DROP;
 827}
 828
 829static int dn_rt_bug(struct sk_buff *skb)
 830{
 831        struct dn_skb_cb *cb = DN_SKB_CB(skb);
 832
 833        net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
 834                            le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
 835
 836        kfree_skb(skb);
 837
 838        return NET_RX_DROP;
 839}
 840
 841static unsigned int dn_dst_default_advmss(const struct dst_entry *dst)
 842{
 843        return dn_mss_from_pmtu(dst->dev, dst_mtu(dst));
 844}
 845
 846static unsigned int dn_dst_mtu(const struct dst_entry *dst)
 847{
 848        unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 849
 850        return mtu ? : dst->dev->mtu;
 851}
 852
 853static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
 854                                             struct sk_buff *skb,
 855                                             const void *daddr)
 856{
 857        return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
 858}
 859
 860static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
 861{
 862        struct dn_fib_info *fi = res->fi;
 863        struct net_device *dev = rt->dst.dev;
 864        unsigned int mss_metric;
 865        struct neighbour *n;
 866
 867        if (fi) {
 868                if (DN_FIB_RES_GW(*res) &&
 869                    DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
 870                        rt->rt_gateway = DN_FIB_RES_GW(*res);
 871                dst_init_metrics(&rt->dst, fi->fib_metrics, true);
 872        }
 873        rt->rt_type = res->type;
 874
 875        if (dev != NULL && rt->n == NULL) {
 876                n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
 877                if (IS_ERR(n))
 878                        return PTR_ERR(n);
 879                rt->n = n;
 880        }
 881
 882        if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
 883                dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
 884        mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
 885        if (mss_metric) {
 886                unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
 887                if (mss_metric > mss)
 888                        dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
 889        }
 890        return 0;
 891}
 892
 893static inline int dn_match_addr(__le16 addr1, __le16 addr2)
 894{
 895        __u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
 896        int match = 16;
 897        while(tmp) {
 898                tmp >>= 1;
 899                match--;
 900        }
 901        return match;
 902}
 903
 904static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
 905{
 906        __le16 saddr = 0;
 907        struct dn_dev *dn_db;
 908        struct dn_ifaddr *ifa;
 909        int best_match = 0;
 910        int ret;
 911
 912        rcu_read_lock();
 913        dn_db = rcu_dereference(dev->dn_ptr);
 914        for (ifa = rcu_dereference(dn_db->ifa_list);
 915             ifa != NULL;
 916             ifa = rcu_dereference(ifa->ifa_next)) {
 917                if (ifa->ifa_scope > scope)
 918                        continue;
 919                if (!daddr) {
 920                        saddr = ifa->ifa_local;
 921                        break;
 922                }
 923                ret = dn_match_addr(daddr, ifa->ifa_local);
 924                if (ret > best_match)
 925                        saddr = ifa->ifa_local;
 926                if (best_match == 0)
 927                        saddr = ifa->ifa_local;
 928        }
 929        rcu_read_unlock();
 930
 931        return saddr;
 932}
 933
 934static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
 935{
 936        return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
 937}
 938
 939static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
 940{
 941        __le16 mask = dnet_make_mask(res->prefixlen);
 942        return (daddr&~mask)|res->fi->fib_nh->nh_gw;
 943}
 944
 945static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard)
 946{
 947        struct flowidn fld = {
 948                .daddr = oldflp->daddr,
 949                .saddr = oldflp->saddr,
 950                .flowidn_scope = RT_SCOPE_UNIVERSE,
 951                .flowidn_mark = oldflp->flowidn_mark,
 952                .flowidn_iif = LOOPBACK_IFINDEX,
 953                .flowidn_oif = oldflp->flowidn_oif,
 954        };
 955        struct dn_route *rt = NULL;
 956        struct net_device *dev_out = NULL, *dev;
 957        struct neighbour *neigh = NULL;
 958        unsigned int hash;
 959        unsigned int flags = 0;
 960        struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
 961        int err;
 962        int free_res = 0;
 963        __le16 gateway = 0;
 964
 965        if (decnet_debug_level & 16)
 966                printk(KERN_DEBUG
 967                       "dn_route_output_slow: dst=%04x src=%04x mark=%d"
 968                       " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
 969                       le16_to_cpu(oldflp->saddr),
 970                       oldflp->flowidn_mark, LOOPBACK_IFINDEX,
 971                       oldflp->flowidn_oif);
 972
 973        /* If we have an output interface, verify its a DECnet device */
 974        if (oldflp->flowidn_oif) {
 975                dev_out = dev_get_by_index(&init_net, oldflp->flowidn_oif);
 976                err = -ENODEV;
 977                if (dev_out && dev_out->dn_ptr == NULL) {
 978                        dev_put(dev_out);
 979                        dev_out = NULL;
 980                }
 981                if (dev_out == NULL)
 982                        goto out;
 983        }
 984
 985        /* If we have a source address, verify that its a local address */
 986        if (oldflp->saddr) {
 987                err = -EADDRNOTAVAIL;
 988
 989                if (dev_out) {
 990                        if (dn_dev_islocal(dev_out, oldflp->saddr))
 991                                goto source_ok;
 992                        dev_put(dev_out);
 993                        goto out;
 994                }
 995                rcu_read_lock();
 996                for_each_netdev_rcu(&init_net, dev) {
 997                        if (!dev->dn_ptr)
 998                                continue;
 999                        if (!dn_dev_islocal(dev, oldflp->saddr))
1000                                continue;
1001                        if ((dev->flags & IFF_LOOPBACK) &&
1002                            oldflp->daddr &&
1003                            !dn_dev_islocal(dev, oldflp->daddr))
1004                                continue;
1005
1006                        dev_out = dev;
1007                        break;
1008                }
1009                rcu_read_unlock();
1010                if (dev_out == NULL)
1011                        goto out;
1012                dev_hold(dev_out);
1013source_ok:
1014                ;
1015        }
1016
1017        /* No destination? Assume its local */
1018        if (!fld.daddr) {
1019                fld.daddr = fld.saddr;
1020
1021                if (dev_out)
1022                        dev_put(dev_out);
1023                err = -EINVAL;
1024                dev_out = init_net.loopback_dev;
1025                if (!dev_out->dn_ptr)
1026                        goto out;
1027                err = -EADDRNOTAVAIL;
1028                dev_hold(dev_out);
1029                if (!fld.daddr) {
1030                        fld.daddr =
1031                        fld.saddr = dnet_select_source(dev_out, 0,
1032                                                       RT_SCOPE_HOST);
1033                        if (!fld.daddr)
1034                                goto out;
1035                }
1036                fld.flowidn_oif = LOOPBACK_IFINDEX;
1037                res.type = RTN_LOCAL;
1038                goto make_route;
1039        }
1040
1041        if (decnet_debug_level & 16)
1042                printk(KERN_DEBUG
1043                       "dn_route_output_slow: initial checks complete."
1044                       " dst=%04x src=%04x oif=%d try_hard=%d\n",
1045                       le16_to_cpu(fld.daddr), le16_to_cpu(fld.saddr),
1046                       fld.flowidn_oif, try_hard);
1047
1048        /*
1049         * N.B. If the kernel is compiled without router support then
1050         * dn_fib_lookup() will evaluate to non-zero so this if () block
1051         * will always be executed.
1052         */
1053        err = -ESRCH;
1054        if (try_hard || (err = dn_fib_lookup(&fld, &res)) != 0) {
1055                struct dn_dev *dn_db;
1056                if (err != -ESRCH)
1057                        goto out;
1058                /*
1059                 * Here the fallback is basically the standard algorithm for
1060                 * routing in endnodes which is described in the DECnet routing
1061                 * docs
1062                 *
1063                 * If we are not trying hard, look in neighbour cache.
1064                 * The result is tested to ensure that if a specific output
1065                 * device/source address was requested, then we honour that
1066                 * here
1067                 */
1068                if (!try_hard) {
1069                        neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fld.daddr);
1070                        if (neigh) {
1071                                if ((oldflp->flowidn_oif &&
1072                                    (neigh->dev->ifindex != oldflp->flowidn_oif)) ||
1073                                    (oldflp->saddr &&
1074                                    (!dn_dev_islocal(neigh->dev,
1075                                                     oldflp->saddr)))) {
1076                                        neigh_release(neigh);
1077                                        neigh = NULL;
1078                                } else {
1079                                        if (dev_out)
1080                                                dev_put(dev_out);
1081                                        if (dn_dev_islocal(neigh->dev, fld.daddr)) {
1082                                                dev_out = init_net.loopback_dev;
1083                                                res.type = RTN_LOCAL;
1084                                        } else {
1085                                                dev_out = neigh->dev;
1086                                        }
1087                                        dev_hold(dev_out);
1088                                        goto select_source;
1089                                }
1090                        }
1091                }
1092
1093                /* Not there? Perhaps its a local address */
1094                if (dev_out == NULL)
1095                        dev_out = dn_dev_get_default();
1096                err = -ENODEV;
1097                if (dev_out == NULL)
1098                        goto out;
1099                dn_db = rcu_dereference_raw(dev_out->dn_ptr);
1100                if (!dn_db)
1101                        goto e_inval;
1102                /* Possible improvement - check all devices for local addr */
1103                if (dn_dev_islocal(dev_out, fld.daddr)) {
1104                        dev_put(dev_out);
1105                        dev_out = init_net.loopback_dev;
1106                        dev_hold(dev_out);
1107                        res.type = RTN_LOCAL;
1108                        goto select_source;
1109                }
1110                /* Not local either.... try sending it to the default router */
1111                neigh = neigh_clone(dn_db->router);
1112                BUG_ON(neigh && neigh->dev != dev_out);
1113
1114                /* Ok then, we assume its directly connected and move on */
1115select_source:
1116                if (neigh)
1117                        gateway = ((struct dn_neigh *)neigh)->addr;
1118                if (gateway == 0)
1119                        gateway = fld.daddr;
1120                if (fld.saddr == 0) {
1121                        fld.saddr = dnet_select_source(dev_out, gateway,
1122                                                       res.type == RTN_LOCAL ?
1123                                                       RT_SCOPE_HOST :
1124                                                       RT_SCOPE_LINK);
1125                        if (fld.saddr == 0 && res.type != RTN_LOCAL)
1126                                goto e_addr;
1127                }
1128                fld.flowidn_oif = dev_out->ifindex;
1129                goto make_route;
1130        }
1131        free_res = 1;
1132
1133        if (res.type == RTN_NAT)
1134                goto e_inval;
1135
1136        if (res.type == RTN_LOCAL) {
1137                if (!fld.saddr)
1138                        fld.saddr = fld.daddr;
1139                if (dev_out)
1140                        dev_put(dev_out);
1141                dev_out = init_net.loopback_dev;
1142                dev_hold(dev_out);
1143                if (!dev_out->dn_ptr)
1144                        goto e_inval;
1145                fld.flowidn_oif = dev_out->ifindex;
1146                if (res.fi)
1147                        dn_fib_info_put(res.fi);
1148                res.fi = NULL;
1149                goto make_route;
1150        }
1151
1152        if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1153                dn_fib_select_multipath(&fld, &res);
1154
1155        /*
1156         * We could add some logic to deal with default routes here and
1157         * get rid of some of the special casing above.
1158         */
1159
1160        if (!fld.saddr)
1161                fld.saddr = DN_FIB_RES_PREFSRC(res);
1162
1163        if (dev_out)
1164                dev_put(dev_out);
1165        dev_out = DN_FIB_RES_DEV(res);
1166        dev_hold(dev_out);
1167        fld.flowidn_oif = dev_out->ifindex;
1168        gateway = DN_FIB_RES_GW(res);
1169
1170make_route:
1171        if (dev_out->flags & IFF_LOOPBACK)
1172                flags |= RTCF_LOCAL;
1173
1174        rt = dst_alloc(&dn_dst_ops, dev_out, 0, DST_OBSOLETE_NONE, DST_HOST);
1175        if (rt == NULL)
1176                goto e_nobufs;
1177
1178        rt->dn_next = NULL;
1179        memset(&rt->fld, 0, sizeof(rt->fld));
1180        rt->fld.saddr        = oldflp->saddr;
1181        rt->fld.daddr        = oldflp->daddr;
1182        rt->fld.flowidn_oif  = oldflp->flowidn_oif;
1183        rt->fld.flowidn_iif  = 0;
1184        rt->fld.flowidn_mark = oldflp->flowidn_mark;
1185
1186        rt->rt_saddr      = fld.saddr;
1187        rt->rt_daddr      = fld.daddr;
1188        rt->rt_gateway    = gateway ? gateway : fld.daddr;
1189        rt->rt_local_src  = fld.saddr;
1190
1191        rt->rt_dst_map    = fld.daddr;
1192        rt->rt_src_map    = fld.saddr;
1193
1194        rt->n = neigh;
1195        neigh = NULL;
1196
1197        rt->dst.lastuse = jiffies;
1198        rt->dst.output  = dn_output;
1199        rt->dst.input   = dn_rt_bug;
1200        rt->rt_flags      = flags;
1201        if (flags & RTCF_LOCAL)
1202                rt->dst.input = dn_nsp_rx;
1203
1204        err = dn_rt_set_next_hop(rt, &res);
1205        if (err)
1206                goto e_neighbour;
1207
1208        hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1209        /* dn_insert_route() increments dst->__refcnt */
1210        dn_insert_route(rt, hash, (struct dn_route **)pprt);
1211
1212done:
1213        if (neigh)
1214                neigh_release(neigh);
1215        if (free_res)
1216                dn_fib_res_put(&res);
1217        if (dev_out)
1218                dev_put(dev_out);
1219out:
1220        return err;
1221
1222e_addr:
1223        err = -EADDRNOTAVAIL;
1224        goto done;
1225e_inval:
1226        err = -EINVAL;
1227        goto done;
1228e_nobufs:
1229        err = -ENOBUFS;
1230        goto done;
1231e_neighbour:
1232        dst_release_immediate(&rt->dst);
1233        goto e_nobufs;
1234}
1235
1236
1237/*
1238 * N.B. The flags may be moved into the flowi at some future stage.
1239 */
1240static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags)
1241{
1242        unsigned int hash = dn_hash(flp->saddr, flp->daddr);
1243        struct dn_route *rt = NULL;
1244
1245        if (!(flags & MSG_TRYHARD)) {
1246                rcu_read_lock_bh();
1247                for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
1248                        rt = rcu_dereference_bh(rt->dn_next)) {
1249                        if ((flp->daddr == rt->fld.daddr) &&
1250                            (flp->saddr == rt->fld.saddr) &&
1251                            (flp->flowidn_mark == rt->fld.flowidn_mark) &&
1252                            dn_is_output_route(rt) &&
1253                            (rt->fld.flowidn_oif == flp->flowidn_oif)) {
1254                                dst_hold_and_use(&rt->dst, jiffies);
1255                                rcu_read_unlock_bh();
1256                                *pprt = &rt->dst;
1257                                return 0;
1258                        }
1259                }
1260                rcu_read_unlock_bh();
1261        }
1262
1263        return dn_route_output_slow(pprt, flp, flags);
1264}
1265
1266static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags)
1267{
1268        int err;
1269
1270        err = __dn_route_output_key(pprt, flp, flags);
1271        if (err == 0 && flp->flowidn_proto) {
1272                *pprt = xfrm_lookup(&init_net, *pprt,
1273                                    flowidn_to_flowi(flp), NULL, 0);
1274                if (IS_ERR(*pprt)) {
1275                        err = PTR_ERR(*pprt);
1276                        *pprt = NULL;
1277                }
1278        }
1279        return err;
1280}
1281
1282int dn_route_output_sock(struct dst_entry __rcu **pprt, struct flowidn *fl, struct sock *sk, int flags)
1283{
1284        int err;
1285
1286        err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1287        if (err == 0 && fl->flowidn_proto) {
1288                *pprt = xfrm_lookup(&init_net, *pprt,
1289                                    flowidn_to_flowi(fl), sk, 0);
1290                if (IS_ERR(*pprt)) {
1291                        err = PTR_ERR(*pprt);
1292                        *pprt = NULL;
1293                }
1294        }
1295        return err;
1296}
1297
1298static int dn_route_input_slow(struct sk_buff *skb)
1299{
1300        struct dn_route *rt = NULL;
1301        struct dn_skb_cb *cb = DN_SKB_CB(skb);
1302        struct net_device *in_dev = skb->dev;
1303        struct net_device *out_dev = NULL;
1304        struct dn_dev *dn_db;
1305        struct neighbour *neigh = NULL;
1306        unsigned int hash;
1307        int flags = 0;
1308        __le16 gateway = 0;
1309        __le16 local_src = 0;
1310        struct flowidn fld = {
1311                .daddr = cb->dst,
1312                .saddr = cb->src,
1313                .flowidn_scope = RT_SCOPE_UNIVERSE,
1314                .flowidn_mark = skb->mark,
1315                .flowidn_iif = skb->dev->ifindex,
1316        };
1317        struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1318        int err = -EINVAL;
1319        int free_res = 0;
1320
1321        dev_hold(in_dev);
1322
1323        if ((dn_db = rcu_dereference(in_dev->dn_ptr)) == NULL)
1324                goto out;
1325
1326        /* Zero source addresses are not allowed */
1327        if (fld.saddr == 0)
1328                goto out;
1329
1330        /*
1331         * In this case we've just received a packet from a source
1332         * outside ourselves pretending to come from us. We don't
1333         * allow it any further to prevent routing loops, spoofing and
1334         * other nasties. Loopback packets already have the dst attached
1335         * so this only affects packets which have originated elsewhere.
1336         */
1337        err  = -ENOTUNIQ;
1338        if (dn_dev_islocal(in_dev, cb->src))
1339                goto out;
1340
1341        err = dn_fib_lookup(&fld, &res);
1342        if (err) {
1343                if (err != -ESRCH)
1344                        goto out;
1345                /*
1346                 * Is the destination us ?
1347                 */
1348                if (!dn_dev_islocal(in_dev, cb->dst))
1349                        goto e_inval;
1350
1351                res.type = RTN_LOCAL;
1352        } else {
1353                __le16 src_map = fld.saddr;
1354                free_res = 1;
1355
1356                out_dev = DN_FIB_RES_DEV(res);
1357                if (out_dev == NULL) {
1358                        net_crit_ratelimited("Bug in dn_route_input_slow() No output device\n");
1359                        goto e_inval;
1360                }
1361                dev_hold(out_dev);
1362
1363                if (res.r)
1364                        src_map = fld.saddr; /* no NAT support for now */
1365
1366                gateway = DN_FIB_RES_GW(res);
1367                if (res.type == RTN_NAT) {
1368                        fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res);
1369                        dn_fib_res_put(&res);
1370                        free_res = 0;
1371                        if (dn_fib_lookup(&fld, &res))
1372                                goto e_inval;
1373                        free_res = 1;
1374                        if (res.type != RTN_UNICAST)
1375                                goto e_inval;
1376                        flags |= RTCF_DNAT;
1377                        gateway = fld.daddr;
1378                }
1379                fld.saddr = src_map;
1380        }
1381
1382        switch(res.type) {
1383        case RTN_UNICAST:
1384                /*
1385                 * Forwarding check here, we only check for forwarding
1386                 * being turned off, if you want to only forward intra
1387                 * area, its up to you to set the routing tables up
1388                 * correctly.
1389                 */
1390                if (dn_db->parms.forwarding == 0)
1391                        goto e_inval;
1392
1393                if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1394                        dn_fib_select_multipath(&fld, &res);
1395
1396                /*
1397                 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1398                 * flag as a hint to set the intra-ethernet bit when
1399                 * forwarding. If we've got NAT in operation, we don't do
1400                 * this optimisation.
1401                 */
1402                if (out_dev == in_dev && !(flags & RTCF_NAT))
1403                        flags |= RTCF_DOREDIRECT;
1404
1405                local_src = DN_FIB_RES_PREFSRC(res);
1406
1407        case RTN_BLACKHOLE:
1408        case RTN_UNREACHABLE:
1409                break;
1410        case RTN_LOCAL:
1411                flags |= RTCF_LOCAL;
1412                fld.saddr = cb->dst;
1413                fld.daddr = cb->src;
1414
1415                /* Routing tables gave us a gateway */
1416                if (gateway)
1417                        goto make_route;
1418
1419                /* Packet was intra-ethernet, so we know its on-link */
1420                if (cb->rt_flags & DN_RT_F_IE) {
1421                        gateway = cb->src;
1422                        goto make_route;
1423                }
1424
1425                /* Use the default router if there is one */
1426                neigh = neigh_clone(dn_db->router);
1427                if (neigh) {
1428                        gateway = ((struct dn_neigh *)neigh)->addr;
1429                        goto make_route;
1430                }
1431
1432                /* Close eyes and pray */
1433                gateway = cb->src;
1434                goto make_route;
1435        default:
1436                goto e_inval;
1437        }
1438
1439make_route:
1440        rt = dst_alloc(&dn_dst_ops, out_dev, 1, DST_OBSOLETE_NONE, DST_HOST);
1441        if (rt == NULL)
1442                goto e_nobufs;
1443
1444        rt->dn_next = NULL;
1445        memset(&rt->fld, 0, sizeof(rt->fld));
1446        rt->rt_saddr      = fld.saddr;
1447        rt->rt_daddr      = fld.daddr;
1448        rt->rt_gateway    = fld.daddr;
1449        if (gateway)
1450                rt->rt_gateway = gateway;
1451        rt->rt_local_src  = local_src ? local_src : rt->rt_saddr;
1452
1453        rt->rt_dst_map    = fld.daddr;
1454        rt->rt_src_map    = fld.saddr;
1455
1456        rt->fld.saddr        = cb->src;
1457        rt->fld.daddr        = cb->dst;
1458        rt->fld.flowidn_oif  = 0;
1459        rt->fld.flowidn_iif  = in_dev->ifindex;
1460        rt->fld.flowidn_mark = fld.flowidn_mark;
1461
1462        rt->n = neigh;
1463        rt->dst.lastuse = jiffies;
1464        rt->dst.output = dn_rt_bug_out;
1465        switch (res.type) {
1466        case RTN_UNICAST:
1467                rt->dst.input = dn_forward;
1468                break;
1469        case RTN_LOCAL:
1470                rt->dst.output = dn_output;
1471                rt->dst.input = dn_nsp_rx;
1472                rt->dst.dev = in_dev;
1473                flags |= RTCF_LOCAL;
1474                break;
1475        default:
1476        case RTN_UNREACHABLE:
1477        case RTN_BLACKHOLE:
1478                rt->dst.input = dst_discard;
1479        }
1480        rt->rt_flags = flags;
1481
1482        err = dn_rt_set_next_hop(rt, &res);
1483        if (err)
1484                goto e_neighbour;
1485
1486        hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1487        /* dn_insert_route() increments dst->__refcnt */
1488        dn_insert_route(rt, hash, &rt);
1489        skb_dst_set(skb, &rt->dst);
1490
1491done:
1492        if (neigh)
1493                neigh_release(neigh);
1494        if (free_res)
1495                dn_fib_res_put(&res);
1496        dev_put(in_dev);
1497        if (out_dev)
1498                dev_put(out_dev);
1499out:
1500        return err;
1501
1502e_inval:
1503        err = -EINVAL;
1504        goto done;
1505
1506e_nobufs:
1507        err = -ENOBUFS;
1508        goto done;
1509
1510e_neighbour:
1511        dst_release_immediate(&rt->dst);
1512        goto done;
1513}
1514
1515static int dn_route_input(struct sk_buff *skb)
1516{
1517        struct dn_route *rt;
1518        struct dn_skb_cb *cb = DN_SKB_CB(skb);
1519        unsigned int hash = dn_hash(cb->src, cb->dst);
1520
1521        if (skb_dst(skb))
1522                return 0;
1523
1524        rcu_read_lock();
1525        for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1526            rt = rcu_dereference(rt->dn_next)) {
1527                if ((rt->fld.saddr == cb->src) &&
1528                    (rt->fld.daddr == cb->dst) &&
1529                    (rt->fld.flowidn_oif == 0) &&
1530                    (rt->fld.flowidn_mark == skb->mark) &&
1531                    (rt->fld.flowidn_iif == cb->iif)) {
1532                        dst_hold_and_use(&rt->dst, jiffies);
1533                        rcu_read_unlock();
1534                        skb_dst_set(skb, (struct dst_entry *)rt);
1535                        return 0;
1536                }
1537        }
1538        rcu_read_unlock();
1539
1540        return dn_route_input_slow(skb);
1541}
1542
1543static int dn_rt_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
1544                           int event, int nowait, unsigned int flags)
1545{
1546        struct dn_route *rt = (struct dn_route *)skb_dst(skb);
1547        struct rtmsg *r;
1548        struct nlmsghdr *nlh;
1549        long expires;
1550
1551        nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags);
1552        if (!nlh)
1553                return -EMSGSIZE;
1554
1555        r = nlmsg_data(nlh);
1556        r->rtm_family = AF_DECnet;
1557        r->rtm_dst_len = 16;
1558        r->rtm_src_len = 0;
1559        r->rtm_tos = 0;
1560        r->rtm_table = RT_TABLE_MAIN;
1561        r->rtm_type = rt->rt_type;
1562        r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1563        r->rtm_scope = RT_SCOPE_UNIVERSE;
1564        r->rtm_protocol = RTPROT_UNSPEC;
1565
1566        if (rt->rt_flags & RTCF_NOTIFY)
1567                r->rtm_flags |= RTM_F_NOTIFY;
1568
1569        if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN) < 0 ||
1570            nla_put_le16(skb, RTA_DST, rt->rt_daddr) < 0)
1571                goto errout;
1572
1573        if (rt->fld.saddr) {
1574                r->rtm_src_len = 16;
1575                if (nla_put_le16(skb, RTA_SRC, rt->fld.saddr) < 0)
1576                        goto errout;
1577        }
1578        if (rt->dst.dev &&
1579            nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex) < 0)
1580                goto errout;
1581
1582        /*
1583         * Note to self - change this if input routes reverse direction when
1584         * they deal only with inputs and not with replies like they do
1585         * currently.
1586         */
1587        if (nla_put_le16(skb, RTA_PREFSRC, rt->rt_local_src) < 0)
1588                goto errout;
1589
1590        if (rt->rt_daddr != rt->rt_gateway &&
1591            nla_put_le16(skb, RTA_GATEWAY, rt->rt_gateway) < 0)
1592                goto errout;
1593
1594        if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
1595                goto errout;
1596
1597        expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
1598        if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires,
1599                               rt->dst.error) < 0)
1600                goto errout;
1601
1602        if (dn_is_input_route(rt) &&
1603            nla_put_u32(skb, RTA_IIF, rt->fld.flowidn_iif) < 0)
1604                goto errout;
1605
1606        nlmsg_end(skb, nlh);
1607        return 0;
1608
1609errout:
1610        nlmsg_cancel(skb, nlh);
1611        return -EMSGSIZE;
1612}
1613
1614const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
1615        [RTA_DST]               = { .type = NLA_U16 },
1616        [RTA_SRC]               = { .type = NLA_U16 },
1617        [RTA_IIF]               = { .type = NLA_U32 },
1618        [RTA_OIF]               = { .type = NLA_U32 },
1619        [RTA_GATEWAY]           = { .type = NLA_U16 },
1620        [RTA_PRIORITY]          = { .type = NLA_U32 },
1621        [RTA_PREFSRC]           = { .type = NLA_U16 },
1622        [RTA_METRICS]           = { .type = NLA_NESTED },
1623        [RTA_MULTIPATH]         = { .type = NLA_NESTED },
1624        [RTA_TABLE]             = { .type = NLA_U32 },
1625        [RTA_MARK]              = { .type = NLA_U32 },
1626};
1627
1628/*
1629 * This is called by both endnodes and routers now.
1630 */
1631static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
1632                             struct netlink_ext_ack *extack)
1633{
1634        struct net *net = sock_net(in_skb->sk);
1635        struct rtmsg *rtm = nlmsg_data(nlh);
1636        struct dn_route *rt = NULL;
1637        struct dn_skb_cb *cb;
1638        int err;
1639        struct sk_buff *skb;
1640        struct flowidn fld;
1641        struct nlattr *tb[RTA_MAX+1];
1642
1643        if (!net_eq(net, &init_net))
1644                return -EINVAL;
1645
1646        err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
1647                                     rtm_dn_policy, extack);
1648        if (err < 0)
1649                return err;
1650
1651        memset(&fld, 0, sizeof(fld));
1652        fld.flowidn_proto = DNPROTO_NSP;
1653
1654        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1655        if (skb == NULL)
1656                return -ENOBUFS;
1657        skb_reset_mac_header(skb);
1658        cb = DN_SKB_CB(skb);
1659
1660        if (tb[RTA_SRC])
1661                fld.saddr = nla_get_le16(tb[RTA_SRC]);
1662
1663        if (tb[RTA_DST])
1664                fld.daddr = nla_get_le16(tb[RTA_DST]);
1665
1666        if (tb[RTA_IIF])
1667                fld.flowidn_iif = nla_get_u32(tb[RTA_IIF]);
1668
1669        if (fld.flowidn_iif) {
1670                struct net_device *dev;
1671                dev = __dev_get_by_index(&init_net, fld.flowidn_iif);
1672                if (!dev || !dev->dn_ptr) {
1673                        kfree_skb(skb);
1674                        return -ENODEV;
1675                }
1676                skb->protocol = htons(ETH_P_DNA_RT);
1677                skb->dev = dev;
1678                cb->src = fld.saddr;
1679                cb->dst = fld.daddr;
1680                local_bh_disable();
1681                err = dn_route_input(skb);
1682                local_bh_enable();
1683                memset(cb, 0, sizeof(struct dn_skb_cb));
1684                rt = (struct dn_route *)skb_dst(skb);
1685                if (!err && -rt->dst.error)
1686                        err = rt->dst.error;
1687        } else {
1688                if (tb[RTA_OIF])
1689                        fld.flowidn_oif = nla_get_u32(tb[RTA_OIF]);
1690
1691                err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
1692        }
1693
1694        skb->dev = NULL;
1695        if (err)
1696                goto out_free;
1697        skb_dst_set(skb, &rt->dst);
1698        if (rtm->rtm_flags & RTM_F_NOTIFY)
1699                rt->rt_flags |= RTCF_NOTIFY;
1700
1701        err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1702        if (err < 0) {
1703                err = -EMSGSIZE;
1704                goto out_free;
1705        }
1706
1707        return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).portid);
1708
1709out_free:
1710        kfree_skb(skb);
1711        return err;
1712}
1713
1714/*
1715 * For routers, this is called from dn_fib_dump, but for endnodes its
1716 * called directly from the rtnetlink dispatch table.
1717 */
1718int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1719{
1720        struct net *net = sock_net(skb->sk);
1721        struct dn_route *rt;
1722        int h, s_h;
1723        int idx, s_idx;
1724        struct rtmsg *rtm;
1725
1726        if (!net_eq(net, &init_net))
1727                return 0;
1728
1729        if (nlmsg_len(cb->nlh) < sizeof(struct rtmsg))
1730                return -EINVAL;
1731
1732        rtm = nlmsg_data(cb->nlh);
1733        if (!(rtm->rtm_flags & RTM_F_CLONED))
1734                return 0;
1735
1736        s_h = cb->args[0];
1737        s_idx = idx = cb->args[1];
1738        for(h = 0; h <= dn_rt_hash_mask; h++) {
1739                if (h < s_h)
1740                        continue;
1741                if (h > s_h)
1742                        s_idx = 0;
1743                rcu_read_lock_bh();
1744                for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
1745                        rt;
1746                        rt = rcu_dereference_bh(rt->dn_next), idx++) {
1747                        if (idx < s_idx)
1748                                continue;
1749                        skb_dst_set(skb, dst_clone(&rt->dst));
1750                        if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).portid,
1751                                        cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1752                                        1, NLM_F_MULTI) < 0) {
1753                                skb_dst_drop(skb);
1754                                rcu_read_unlock_bh();
1755                                goto done;
1756                        }
1757                        skb_dst_drop(skb);
1758                }
1759                rcu_read_unlock_bh();
1760        }
1761
1762done:
1763        cb->args[0] = h;
1764        cb->args[1] = idx;
1765        return skb->len;
1766}
1767
1768#ifdef CONFIG_PROC_FS
1769struct dn_rt_cache_iter_state {
1770        int bucket;
1771};
1772
1773static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1774{
1775        struct dn_route *rt = NULL;
1776        struct dn_rt_cache_iter_state *s = seq->private;
1777
1778        for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1779                rcu_read_lock_bh();
1780                rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1781                if (rt)
1782                        break;
1783                rcu_read_unlock_bh();
1784        }
1785        return rt;
1786}
1787
1788static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1789{
1790        struct dn_rt_cache_iter_state *s = seq->private;
1791
1792        rt = rcu_dereference_bh(rt->dn_next);
1793        while (!rt) {
1794                rcu_read_unlock_bh();
1795                if (--s->bucket < 0)
1796                        break;
1797                rcu_read_lock_bh();
1798                rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1799        }
1800        return rt;
1801}
1802
1803static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1804{
1805        struct dn_route *rt = dn_rt_cache_get_first(seq);
1806
1807        if (rt) {
1808                while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1809                        --*pos;
1810        }
1811        return *pos ? NULL : rt;
1812}
1813
1814static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1815{
1816        struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1817        ++*pos;
1818        return rt;
1819}
1820
1821static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1822{
1823        if (v)
1824                rcu_read_unlock_bh();
1825}
1826
1827static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1828{
1829        struct dn_route *rt = v;
1830        char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1831
1832        seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1833                   rt->dst.dev ? rt->dst.dev->name : "*",
1834                   dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
1835                   dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
1836                   atomic_read(&rt->dst.__refcnt),
1837                   rt->dst.__use, 0);
1838        return 0;
1839}
1840
1841static const struct seq_operations dn_rt_cache_seq_ops = {
1842        .start  = dn_rt_cache_seq_start,
1843        .next   = dn_rt_cache_seq_next,
1844        .stop   = dn_rt_cache_seq_stop,
1845        .show   = dn_rt_cache_seq_show,
1846};
1847#endif /* CONFIG_PROC_FS */
1848
1849void __init dn_route_init(void)
1850{
1851        int i, goal, order;
1852
1853        dn_dst_ops.kmem_cachep =
1854                kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1855                                  SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1856        dst_entries_init(&dn_dst_ops);
1857        timer_setup(&dn_route_timer, dn_dst_check_expire, 0);
1858        dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1859        add_timer(&dn_route_timer);
1860
1861        goal = totalram_pages() >> (26 - PAGE_SHIFT);
1862
1863        for(order = 0; (1UL << order) < goal; order++)
1864                /* NOTHING */;
1865
1866        /*
1867         * Only want 1024 entries max, since the table is very, very unlikely
1868         * to be larger than that.
1869         */
1870        while(order && ((((1UL << order) * PAGE_SIZE) /
1871                                sizeof(struct dn_rt_hash_bucket)) >= 2048))
1872                order--;
1873
1874        do {
1875                dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1876                        sizeof(struct dn_rt_hash_bucket);
1877                while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1878                        dn_rt_hash_mask--;
1879                dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1880                        __get_free_pages(GFP_ATOMIC, order);
1881        } while (dn_rt_hash_table == NULL && --order > 0);
1882
1883        if (!dn_rt_hash_table)
1884                panic("Failed to allocate DECnet route cache hash table\n");
1885
1886        printk(KERN_INFO
1887                "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1888                dn_rt_hash_mask,
1889                (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1890
1891        dn_rt_hash_mask--;
1892        for(i = 0; i <= dn_rt_hash_mask; i++) {
1893                spin_lock_init(&dn_rt_hash_table[i].lock);
1894                dn_rt_hash_table[i].chain = NULL;
1895        }
1896
1897        dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1898
1899        proc_create_seq_private("decnet_cache", 0444, init_net.proc_net,
1900                        &dn_rt_cache_seq_ops,
1901                        sizeof(struct dn_rt_cache_iter_state), NULL);
1902
1903#ifdef CONFIG_DECNET_ROUTER
1904        rtnl_register_module(THIS_MODULE, PF_DECnet, RTM_GETROUTE,
1905                             dn_cache_getroute, dn_fib_dump, 0);
1906#else
1907        rtnl_register_module(THIS_MODULE, PF_DECnet, RTM_GETROUTE,
1908                             dn_cache_getroute, dn_cache_dump, 0);
1909#endif
1910}
1911
1912void __exit dn_route_cleanup(void)
1913{
1914        del_timer(&dn_route_timer);
1915        dn_run_flush(NULL);
1916
1917        remove_proc_entry("decnet_cache", init_net.proc_net);
1918        dst_entries_destroy(&dn_dst_ops);
1919}
1920