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
  95struct dn_rt_hash_bucket
  96{
  97	struct dn_route __rcu *chain;
  98	spinlock_t lock;
  99};
 100
 101extern struct neigh_table dn_neigh_table;
 102
 103
 104static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
 105
 106static const int dn_rt_min_delay = 2 * HZ;
 107static const int dn_rt_max_delay = 10 * HZ;
 108static const int dn_rt_mtu_expires = 10 * 60 * HZ;
 109
 110static unsigned long dn_rt_deadline;
 111
 112static int dn_dst_gc(struct dst_ops *ops);
 113static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
 114static unsigned int dn_dst_default_advmss(const struct dst_entry *dst);
 115static unsigned int dn_dst_mtu(const struct dst_entry *dst);
 116static void dn_dst_destroy(struct dst_entry *);
 117static void dn_dst_ifdown(struct dst_entry *, struct net_device *dev, int how);
 118static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
 119static void dn_dst_link_failure(struct sk_buff *);
 120static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
 121			       struct sk_buff *skb , u32 mtu);
 122static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
 123			    struct sk_buff *skb);
 124static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
 125					     struct sk_buff *skb,
 126					     const void *daddr);
 127static int dn_route_input(struct sk_buff *);
 128static void dn_run_flush(unsigned long dummy);
 129
 130static struct dn_rt_hash_bucket *dn_rt_hash_table;
 131static unsigned int dn_rt_hash_mask;
 132
 133static struct timer_list dn_route_timer;
 134static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
 135int decnet_dst_gc_interval = 2;
 136
 137static struct dst_ops dn_dst_ops = {
 138	.family =		PF_DECnet,
 139	.gc_thresh =		128,
 140	.gc =			dn_dst_gc,
 141	.check =		dn_dst_check,
 142	.default_advmss =	dn_dst_default_advmss,
 143	.mtu =			dn_dst_mtu,
 144	.cow_metrics =		dst_cow_metrics_generic,
 145	.destroy =		dn_dst_destroy,
 146	.ifdown =		dn_dst_ifdown,
 147	.negative_advice =	dn_dst_negative_advice,
 148	.link_failure =		dn_dst_link_failure,
 149	.update_pmtu =		dn_dst_update_pmtu,
 150	.redirect =		dn_dst_redirect,
 151	.neigh_lookup =		dn_dst_neigh_lookup,
 152};
 153
 154static void dn_dst_destroy(struct dst_entry *dst)
 155{
 156	struct dn_route *rt = (struct dn_route *) dst;
 157
 158	if (rt->n)
 159		neigh_release(rt->n);
 160	dst_destroy_metrics_generic(dst);
 161}
 162
 163static void dn_dst_ifdown(struct dst_entry *dst, struct net_device *dev, int how)
 164{
 165	if (how) {
 166		struct dn_route *rt = (struct dn_route *) dst;
 167		struct neighbour *n = rt->n;
 168
 169		if (n && n->dev == dev) {
 170			n->dev = dev_net(dev)->loopback_dev;
 171			dev_hold(n->dev);
 172			dev_put(dev);
 173		}
 174	}
 175}
 176
 177static __inline__ unsigned int dn_hash(__le16 src, __le16 dst)
 178{
 179	__u16 tmp = (__u16 __force)(src ^ dst);
 180	tmp ^= (tmp >> 3);
 181	tmp ^= (tmp >> 5);
 182	tmp ^= (tmp >> 10);
 183	return dn_rt_hash_mask & (unsigned int)tmp;
 184}
 185
 186static inline void dnrt_free(struct dn_route *rt)
 187{
 188	call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
 189}
 190
 191static inline void dnrt_drop(struct dn_route *rt)
 192{
 193	dst_release(&rt->dst);
 194	call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
 195}
 196
 197static void dn_dst_check_expire(unsigned long dummy)
 198{
 199	int i;
 200	struct dn_route *rt;
 201	struct dn_route __rcu **rtp;
 202	unsigned long now = jiffies;
 203	unsigned long expire = 120 * HZ;
 204
 205	for (i = 0; i <= dn_rt_hash_mask; i++) {
 206		rtp = &dn_rt_hash_table[i].chain;
 207
 208		spin_lock(&dn_rt_hash_table[i].lock);
 209		while ((rt = rcu_dereference_protected(*rtp,
 210						lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
 211			if (atomic_read(&rt->dst.__refcnt) ||
 212					(now - rt->dst.lastuse) < expire) {
 213				rtp = &rt->dst.dn_next;
 214				continue;
 215			}
 216			*rtp = rt->dst.dn_next;
 217			rt->dst.dn_next = NULL;
 218			dnrt_free(rt);
 
 219		}
 220		spin_unlock(&dn_rt_hash_table[i].lock);
 221
 222		if ((jiffies - now) > 0)
 223			break;
 224	}
 225
 226	mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ);
 227}
 228
 229static int dn_dst_gc(struct dst_ops *ops)
 230{
 231	struct dn_route *rt;
 232	struct dn_route __rcu **rtp;
 233	int i;
 234	unsigned long now = jiffies;
 235	unsigned long expire = 10 * HZ;
 236
 237	for (i = 0; i <= dn_rt_hash_mask; i++) {
 238
 239		spin_lock_bh(&dn_rt_hash_table[i].lock);
 240		rtp = &dn_rt_hash_table[i].chain;
 241
 242		while ((rt = rcu_dereference_protected(*rtp,
 243						lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
 244			if (atomic_read(&rt->dst.__refcnt) ||
 245					(now - rt->dst.lastuse) < expire) {
 246				rtp = &rt->dst.dn_next;
 247				continue;
 248			}
 249			*rtp = rt->dst.dn_next;
 250			rt->dst.dn_next = NULL;
 251			dnrt_drop(rt);
 
 252			break;
 253		}
 254		spin_unlock_bh(&dn_rt_hash_table[i].lock);
 255	}
 256
 257	return 0;
 258}
 259
 260/*
 261 * The decnet standards don't impose a particular minimum mtu, what they
 262 * do insist on is that the routing layer accepts a datagram of at least
 263 * 230 bytes long. Here we have to subtract the routing header length from
 264 * 230 to get the minimum acceptable mtu. If there is no neighbour, then we
 265 * assume the worst and use a long header size.
 266 *
 267 * We update both the mtu and the advertised mss (i.e. the segment size we
 268 * advertise to the other end).
 269 */
 270static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
 271			       struct sk_buff *skb, u32 mtu)
 272{
 273	struct dn_route *rt = (struct dn_route *) dst;
 274	struct neighbour *n = rt->n;
 275	u32 min_mtu = 230;
 276	struct dn_dev *dn;
 277
 278	dn = n ? rcu_dereference_raw(n->dev->dn_ptr) : NULL;
 279
 280	if (dn && dn->use_long == 0)
 281		min_mtu -= 6;
 282	else
 283		min_mtu -= 21;
 284
 285	if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= min_mtu) {
 286		if (!(dst_metric_locked(dst, RTAX_MTU))) {
 287			dst_metric_set(dst, RTAX_MTU, mtu);
 288			dst_set_expires(dst, dn_rt_mtu_expires);
 289		}
 290		if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
 291			u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
 292			u32 existing_mss = dst_metric_raw(dst, RTAX_ADVMSS);
 293			if (!existing_mss || existing_mss > mss)
 294				dst_metric_set(dst, RTAX_ADVMSS, mss);
 295		}
 296	}
 297}
 298
 299static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
 300			    struct sk_buff *skb)
 301{
 302}
 303
 304/*
 305 * When a route has been marked obsolete. (e.g. routing cache flush)
 306 */
 307static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
 308{
 309	return NULL;
 310}
 311
 312static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
 313{
 314	dst_release(dst);
 315	return NULL;
 316}
 317
 318static void dn_dst_link_failure(struct sk_buff *skb)
 319{
 320}
 321
 322static inline int compare_keys(struct flowidn *fl1, struct flowidn *fl2)
 323{
 324	return ((fl1->daddr ^ fl2->daddr) |
 325		(fl1->saddr ^ fl2->saddr) |
 326		(fl1->flowidn_mark ^ fl2->flowidn_mark) |
 327		(fl1->flowidn_scope ^ fl2->flowidn_scope) |
 328		(fl1->flowidn_oif ^ fl2->flowidn_oif) |
 329		(fl1->flowidn_iif ^ fl2->flowidn_iif)) == 0;
 330}
 331
 332static int dn_insert_route(struct dn_route *rt, unsigned int hash, struct dn_route **rp)
 333{
 334	struct dn_route *rth;
 335	struct dn_route __rcu **rthp;
 336	unsigned long now = jiffies;
 337
 338	rthp = &dn_rt_hash_table[hash].chain;
 339
 340	spin_lock_bh(&dn_rt_hash_table[hash].lock);
 341	while ((rth = rcu_dereference_protected(*rthp,
 342						lockdep_is_held(&dn_rt_hash_table[hash].lock))) != NULL) {
 343		if (compare_keys(&rth->fld, &rt->fld)) {
 344			/* Put it first */
 345			*rthp = rth->dst.dn_next;
 346			rcu_assign_pointer(rth->dst.dn_next,
 347					   dn_rt_hash_table[hash].chain);
 348			rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
 349
 350			dst_use(&rth->dst, now);
 351			spin_unlock_bh(&dn_rt_hash_table[hash].lock);
 352
 353			dnrt_drop(rt);
 354			*rp = rth;
 355			return 0;
 356		}
 357		rthp = &rth->dst.dn_next;
 358	}
 359
 360	rcu_assign_pointer(rt->dst.dn_next, dn_rt_hash_table[hash].chain);
 361	rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
 362
 363	dst_use(&rt->dst, now);
 364	spin_unlock_bh(&dn_rt_hash_table[hash].lock);
 365	*rp = rt;
 366	return 0;
 367}
 368
 369static void dn_run_flush(unsigned long dummy)
 370{
 371	int i;
 372	struct dn_route *rt, *next;
 373
 374	for (i = 0; i < dn_rt_hash_mask; i++) {
 375		spin_lock_bh(&dn_rt_hash_table[i].lock);
 376
 377		if ((rt = xchg((struct dn_route **)&dn_rt_hash_table[i].chain, NULL)) == NULL)
 378			goto nothing_to_declare;
 379
 380		for(; rt; rt = next) {
 381			next = rcu_dereference_raw(rt->dst.dn_next);
 382			RCU_INIT_POINTER(rt->dst.dn_next, NULL);
 383			dst_free((struct dst_entry *)rt);
 
 384		}
 385
 386nothing_to_declare:
 387		spin_unlock_bh(&dn_rt_hash_table[i].lock);
 388	}
 389}
 390
 391static DEFINE_SPINLOCK(dn_rt_flush_lock);
 392
 393void dn_rt_cache_flush(int delay)
 394{
 395	unsigned long now = jiffies;
 396	int user_mode = !in_interrupt();
 397
 398	if (delay < 0)
 399		delay = dn_rt_min_delay;
 400
 401	spin_lock_bh(&dn_rt_flush_lock);
 402
 403	if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
 404		long tmo = (long)(dn_rt_deadline - now);
 405
 406		if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
 407			tmo = 0;
 408
 409		if (delay > tmo)
 410			delay = tmo;
 411	}
 412
 413	if (delay <= 0) {
 414		spin_unlock_bh(&dn_rt_flush_lock);
 415		dn_run_flush(0);
 416		return;
 417	}
 418
 419	if (dn_rt_deadline == 0)
 420		dn_rt_deadline = now + dn_rt_max_delay;
 421
 422	dn_rt_flush_timer.expires = now + delay;
 423	add_timer(&dn_rt_flush_timer);
 424	spin_unlock_bh(&dn_rt_flush_lock);
 425}
 426
 427/**
 428 * dn_return_short - Return a short packet to its sender
 429 * @skb: The packet to return
 430 *
 431 */
 432static int dn_return_short(struct sk_buff *skb)
 433{
 434	struct dn_skb_cb *cb;
 435	unsigned char *ptr;
 436	__le16 *src;
 437	__le16 *dst;
 438
 439	/* Add back headers */
 440	skb_push(skb, skb->data - skb_network_header(skb));
 441
 442	if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
 443		return NET_RX_DROP;
 444
 445	cb = DN_SKB_CB(skb);
 446	/* Skip packet length and point to flags */
 447	ptr = skb->data + 2;
 448	*ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
 449
 450	dst = (__le16 *)ptr;
 451	ptr += 2;
 452	src = (__le16 *)ptr;
 453	ptr += 2;
 454	*ptr = 0; /* Zero hop count */
 455
 456	swap(*src, *dst);
 457
 458	skb->pkt_type = PACKET_OUTGOING;
 459	dn_rt_finish_output(skb, NULL, NULL);
 460	return NET_RX_SUCCESS;
 461}
 462
 463/**
 464 * dn_return_long - Return a long packet to its sender
 465 * @skb: The long format packet to return
 466 *
 467 */
 468static int dn_return_long(struct sk_buff *skb)
 469{
 470	struct dn_skb_cb *cb;
 471	unsigned char *ptr;
 472	unsigned char *src_addr, *dst_addr;
 473	unsigned char tmp[ETH_ALEN];
 474
 475	/* Add back all headers */
 476	skb_push(skb, skb->data - skb_network_header(skb));
 477
 478	if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
 479		return NET_RX_DROP;
 480
 481	cb = DN_SKB_CB(skb);
 482	/* Ignore packet length and point to flags */
 483	ptr = skb->data + 2;
 484
 485	/* Skip padding */
 486	if (*ptr & DN_RT_F_PF) {
 487		char padlen = (*ptr & ~DN_RT_F_PF);
 488		ptr += padlen;
 489	}
 490
 491	*ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
 492	ptr += 2;
 493	dst_addr = ptr;
 494	ptr += 8;
 495	src_addr = ptr;
 496	ptr += 6;
 497	*ptr = 0; /* Zero hop count */
 498
 499	/* Swap source and destination */
 500	memcpy(tmp, src_addr, ETH_ALEN);
 501	memcpy(src_addr, dst_addr, ETH_ALEN);
 502	memcpy(dst_addr, tmp, ETH_ALEN);
 503
 504	skb->pkt_type = PACKET_OUTGOING;
 505	dn_rt_finish_output(skb, dst_addr, src_addr);
 506	return NET_RX_SUCCESS;
 507}
 508
 509/**
 510 * dn_route_rx_packet - Try and find a route for an incoming packet
 511 * @skb: The packet to find a route for
 512 *
 513 * Returns: result of input function if route is found, error code otherwise
 514 */
 515static int dn_route_rx_packet(struct net *net, struct sock *sk, struct sk_buff *skb)
 516{
 517	struct dn_skb_cb *cb;
 518	int err;
 519
 520	if ((err = dn_route_input(skb)) == 0)
 521		return dst_input(skb);
 522
 523	cb = DN_SKB_CB(skb);
 524	if (decnet_debug_level & 4) {
 525		char *devname = skb->dev ? skb->dev->name : "???";
 526
 527		printk(KERN_DEBUG
 528			"DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
 529			(int)cb->rt_flags, devname, skb->len,
 530			le16_to_cpu(cb->src), le16_to_cpu(cb->dst),
 531			err, skb->pkt_type);
 532	}
 533
 534	if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
 535		switch (cb->rt_flags & DN_RT_PKT_MSK) {
 536		case DN_RT_PKT_SHORT:
 537			return dn_return_short(skb);
 538		case DN_RT_PKT_LONG:
 539			return dn_return_long(skb);
 540		}
 541	}
 542
 543	kfree_skb(skb);
 544	return NET_RX_DROP;
 545}
 546
 547static int dn_route_rx_long(struct sk_buff *skb)
 548{
 549	struct dn_skb_cb *cb = DN_SKB_CB(skb);
 550	unsigned char *ptr = skb->data;
 551
 552	if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
 553		goto drop_it;
 554
 555	skb_pull(skb, 20);
 556	skb_reset_transport_header(skb);
 557
 558	/* Destination info */
 559	ptr += 2;
 560	cb->dst = dn_eth2dn(ptr);
 561	if (memcmp(ptr, dn_hiord_addr, 4) != 0)
 562		goto drop_it;
 563	ptr += 6;
 564
 565
 566	/* Source info */
 567	ptr += 2;
 568	cb->src = dn_eth2dn(ptr);
 569	if (memcmp(ptr, dn_hiord_addr, 4) != 0)
 570		goto drop_it;
 571	ptr += 6;
 572	/* Other junk */
 573	ptr++;
 574	cb->hops = *ptr++; /* Visit Count */
 575
 576	return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
 577		       &init_net, NULL, skb, skb->dev, NULL,
 578		       dn_route_rx_packet);
 579
 580drop_it:
 581	kfree_skb(skb);
 582	return NET_RX_DROP;
 583}
 584
 585
 586
 587static int dn_route_rx_short(struct sk_buff *skb)
 588{
 589	struct dn_skb_cb *cb = DN_SKB_CB(skb);
 590	unsigned char *ptr = skb->data;
 591
 592	if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
 593		goto drop_it;
 594
 595	skb_pull(skb, 5);
 596	skb_reset_transport_header(skb);
 597
 598	cb->dst = *(__le16 *)ptr;
 599	ptr += 2;
 600	cb->src = *(__le16 *)ptr;
 601	ptr += 2;
 602	cb->hops = *ptr & 0x3f;
 603
 604	return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
 605		       &init_net, NULL, skb, skb->dev, NULL,
 606		       dn_route_rx_packet);
 607
 608drop_it:
 609	kfree_skb(skb);
 610	return NET_RX_DROP;
 611}
 612
 613static int dn_route_discard(struct net *net, struct sock *sk, struct sk_buff *skb)
 614{
 615	/*
 616	 * I know we drop the packet here, but thats considered success in
 617	 * this case
 618	 */
 619	kfree_skb(skb);
 620	return NET_RX_SUCCESS;
 621}
 622
 623static int dn_route_ptp_hello(struct net *net, struct sock *sk, struct sk_buff *skb)
 624{
 625	dn_dev_hello(skb);
 626	dn_neigh_pointopoint_hello(skb);
 627	return NET_RX_SUCCESS;
 628}
 629
 630int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 631{
 632	struct dn_skb_cb *cb;
 633	unsigned char flags = 0;
 634	__u16 len = le16_to_cpu(*(__le16 *)skb->data);
 635	struct dn_dev *dn = rcu_dereference(dev->dn_ptr);
 636	unsigned char padlen = 0;
 637
 638	if (!net_eq(dev_net(dev), &init_net))
 639		goto dump_it;
 640
 641	if (dn == NULL)
 642		goto dump_it;
 643
 644	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 645		goto out;
 646
 647	if (!pskb_may_pull(skb, 3))
 648		goto dump_it;
 649
 650	skb_pull(skb, 2);
 651
 652	if (len > skb->len)
 653		goto dump_it;
 654
 655	skb_trim(skb, len);
 656
 657	flags = *skb->data;
 658
 659	cb = DN_SKB_CB(skb);
 660	cb->stamp = jiffies;
 661	cb->iif = dev->ifindex;
 662
 663	/*
 664	 * If we have padding, remove it.
 665	 */
 666	if (flags & DN_RT_F_PF) {
 667		padlen = flags & ~DN_RT_F_PF;
 668		if (!pskb_may_pull(skb, padlen + 1))
 669			goto dump_it;
 670		skb_pull(skb, padlen);
 671		flags = *skb->data;
 672	}
 673
 674	skb_reset_network_header(skb);
 675
 676	/*
 677	 * Weed out future version DECnet
 678	 */
 679	if (flags & DN_RT_F_VER)
 680		goto dump_it;
 681
 682	cb->rt_flags = flags;
 683
 684	if (decnet_debug_level & 1)
 685		printk(KERN_DEBUG
 686			"dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
 687			(int)flags, (dev) ? dev->name : "???", len, skb->len,
 688			padlen);
 689
 690	if (flags & DN_RT_PKT_CNTL) {
 691		if (unlikely(skb_linearize(skb)))
 692			goto dump_it;
 693
 694		switch (flags & DN_RT_CNTL_MSK) {
 695		case DN_RT_PKT_INIT:
 696			dn_dev_init_pkt(skb);
 697			break;
 698		case DN_RT_PKT_VERI:
 699			dn_dev_veri_pkt(skb);
 700			break;
 701		}
 702
 703		if (dn->parms.state != DN_DEV_S_RU)
 704			goto dump_it;
 705
 706		switch (flags & DN_RT_CNTL_MSK) {
 707		case DN_RT_PKT_HELO:
 708			return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 709				       &init_net, NULL, skb, skb->dev, NULL,
 710				       dn_route_ptp_hello);
 711
 712		case DN_RT_PKT_L1RT:
 713		case DN_RT_PKT_L2RT:
 714			return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE,
 715				       &init_net, NULL, skb, skb->dev, NULL,
 716				       dn_route_discard);
 717		case DN_RT_PKT_ERTH:
 718			return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 719				       &init_net, NULL, skb, skb->dev, NULL,
 720				       dn_neigh_router_hello);
 721
 722		case DN_RT_PKT_EEDH:
 723			return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
 724				       &init_net, NULL, skb, skb->dev, NULL,
 725				       dn_neigh_endnode_hello);
 726		}
 727	} else {
 728		if (dn->parms.state != DN_DEV_S_RU)
 729			goto dump_it;
 730
 731		skb_pull(skb, 1); /* Pull flags */
 732
 733		switch (flags & DN_RT_PKT_MSK) {
 734		case DN_RT_PKT_LONG:
 735			return dn_route_rx_long(skb);
 736		case DN_RT_PKT_SHORT:
 737			return dn_route_rx_short(skb);
 738		}
 739	}
 740
 741dump_it:
 742	kfree_skb(skb);
 743out:
 744	return NET_RX_DROP;
 745}
 746
 747static int dn_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 748{
 749	struct dst_entry *dst = skb_dst(skb);
 750	struct dn_route *rt = (struct dn_route *)dst;
 751	struct net_device *dev = dst->dev;
 752	struct dn_skb_cb *cb = DN_SKB_CB(skb);
 753
 754	int err = -EINVAL;
 755
 756	if (rt->n == NULL)
 757		goto error;
 758
 759	skb->dev = dev;
 760
 761	cb->src = rt->rt_saddr;
 762	cb->dst = rt->rt_daddr;
 763
 764	/*
 765	 * Always set the Intra-Ethernet bit on all outgoing packets
 766	 * originated on this node. Only valid flag from upper layers
 767	 * is return-to-sender-requested. Set hop count to 0 too.
 768	 */
 769	cb->rt_flags &= ~DN_RT_F_RQR;
 770	cb->rt_flags |= DN_RT_F_IE;
 771	cb->hops = 0;
 772
 773	return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT,
 774		       &init_net, sk, skb, NULL, dev,
 775		       dn_to_neigh_output);
 776
 777error:
 778	net_dbg_ratelimited("dn_output: This should not happen\n");
 779
 780	kfree_skb(skb);
 781
 782	return err;
 783}
 784
 785static int dn_forward(struct sk_buff *skb)
 786{
 787	struct dn_skb_cb *cb = DN_SKB_CB(skb);
 788	struct dst_entry *dst = skb_dst(skb);
 789	struct dn_dev *dn_db = rcu_dereference(dst->dev->dn_ptr);
 790	struct dn_route *rt;
 791	int header_len;
 792	struct net_device *dev = skb->dev;
 793
 794	if (skb->pkt_type != PACKET_HOST)
 795		goto drop;
 796
 797	/* Ensure that we have enough space for headers */
 798	rt = (struct dn_route *)skb_dst(skb);
 799	header_len = dn_db->use_long ? 21 : 6;
 800	if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+header_len))
 801		goto drop;
 802
 803	/*
 804	 * Hop count exceeded.
 805	 */
 806	if (++cb->hops > 30)
 807		goto drop;
 808
 809	skb->dev = rt->dst.dev;
 810
 811	/*
 812	 * If packet goes out same interface it came in on, then set
 813	 * the Intra-Ethernet bit. This has no effect for short
 814	 * packets, so we don't need to test for them here.
 815	 */
 816	cb->rt_flags &= ~DN_RT_F_IE;
 817	if (rt->rt_flags & RTCF_DOREDIRECT)
 818		cb->rt_flags |= DN_RT_F_IE;
 819
 820	return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD,
 821		       &init_net, NULL, skb, dev, skb->dev,
 822		       dn_to_neigh_output);
 823
 824drop:
 825	kfree_skb(skb);
 826	return NET_RX_DROP;
 827}
 828
 829/*
 830 * Used to catch bugs. This should never normally get
 831 * called.
 832 */
 833static int dn_rt_bug_out(struct net *net, struct sock *sk, struct sk_buff *skb)
 834{
 835	struct dn_skb_cb *cb = DN_SKB_CB(skb);
 836
 837	net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
 838			    le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
 839
 840	kfree_skb(skb);
 841
 842	return NET_RX_DROP;
 843}
 844
 845static int dn_rt_bug(struct sk_buff *skb)
 846{
 847	struct dn_skb_cb *cb = DN_SKB_CB(skb);
 848
 849	net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
 850			    le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
 851
 852	kfree_skb(skb);
 853
 854	return NET_RX_DROP;
 855}
 856
 857static unsigned int dn_dst_default_advmss(const struct dst_entry *dst)
 858{
 859	return dn_mss_from_pmtu(dst->dev, dst_mtu(dst));
 860}
 861
 862static unsigned int dn_dst_mtu(const struct dst_entry *dst)
 863{
 864	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 865
 866	return mtu ? : dst->dev->mtu;
 867}
 868
 869static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
 870					     struct sk_buff *skb,
 871					     const void *daddr)
 872{
 873	return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
 874}
 875
 876static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
 877{
 878	struct dn_fib_info *fi = res->fi;
 879	struct net_device *dev = rt->dst.dev;
 880	unsigned int mss_metric;
 881	struct neighbour *n;
 882
 883	if (fi) {
 884		if (DN_FIB_RES_GW(*res) &&
 885		    DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
 886			rt->rt_gateway = DN_FIB_RES_GW(*res);
 887		dst_init_metrics(&rt->dst, fi->fib_metrics, true);
 888	}
 889	rt->rt_type = res->type;
 890
 891	if (dev != NULL && rt->n == NULL) {
 892		n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
 893		if (IS_ERR(n))
 894			return PTR_ERR(n);
 895		rt->n = n;
 896	}
 897
 898	if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
 899		dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
 900	mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
 901	if (mss_metric) {
 902		unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
 903		if (mss_metric > mss)
 904			dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
 905	}
 906	return 0;
 907}
 908
 909static inline int dn_match_addr(__le16 addr1, __le16 addr2)
 910{
 911	__u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
 912	int match = 16;
 913	while(tmp) {
 914		tmp >>= 1;
 915		match--;
 916	}
 917	return match;
 918}
 919
 920static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
 921{
 922	__le16 saddr = 0;
 923	struct dn_dev *dn_db;
 924	struct dn_ifaddr *ifa;
 925	int best_match = 0;
 926	int ret;
 927
 928	rcu_read_lock();
 929	dn_db = rcu_dereference(dev->dn_ptr);
 930	for (ifa = rcu_dereference(dn_db->ifa_list);
 931	     ifa != NULL;
 932	     ifa = rcu_dereference(ifa->ifa_next)) {
 933		if (ifa->ifa_scope > scope)
 934			continue;
 935		if (!daddr) {
 936			saddr = ifa->ifa_local;
 937			break;
 938		}
 939		ret = dn_match_addr(daddr, ifa->ifa_local);
 940		if (ret > best_match)
 941			saddr = ifa->ifa_local;
 942		if (best_match == 0)
 943			saddr = ifa->ifa_local;
 944	}
 945	rcu_read_unlock();
 946
 947	return saddr;
 948}
 949
 950static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
 951{
 952	return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
 953}
 954
 955static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
 956{
 957	__le16 mask = dnet_make_mask(res->prefixlen);
 958	return (daddr&~mask)|res->fi->fib_nh->nh_gw;
 959}
 960
 961static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard)
 962{
 963	struct flowidn fld = {
 964		.daddr = oldflp->daddr,
 965		.saddr = oldflp->saddr,
 966		.flowidn_scope = RT_SCOPE_UNIVERSE,
 967		.flowidn_mark = oldflp->flowidn_mark,
 968		.flowidn_iif = LOOPBACK_IFINDEX,
 969		.flowidn_oif = oldflp->flowidn_oif,
 970	};
 971	struct dn_route *rt = NULL;
 972	struct net_device *dev_out = NULL, *dev;
 973	struct neighbour *neigh = NULL;
 974	unsigned int hash;
 975	unsigned int flags = 0;
 976	struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
 977	int err;
 978	int free_res = 0;
 979	__le16 gateway = 0;
 980
 981	if (decnet_debug_level & 16)
 982		printk(KERN_DEBUG
 983		       "dn_route_output_slow: dst=%04x src=%04x mark=%d"
 984		       " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
 985		       le16_to_cpu(oldflp->saddr),
 986		       oldflp->flowidn_mark, LOOPBACK_IFINDEX,
 987		       oldflp->flowidn_oif);
 988
 989	/* If we have an output interface, verify its a DECnet device */
 990	if (oldflp->flowidn_oif) {
 991		dev_out = dev_get_by_index(&init_net, oldflp->flowidn_oif);
 992		err = -ENODEV;
 993		if (dev_out && dev_out->dn_ptr == NULL) {
 994			dev_put(dev_out);
 995			dev_out = NULL;
 996		}
 997		if (dev_out == NULL)
 998			goto out;
 999	}
1000
1001	/* If we have a source address, verify that its a local address */
1002	if (oldflp->saddr) {
1003		err = -EADDRNOTAVAIL;
1004
1005		if (dev_out) {
1006			if (dn_dev_islocal(dev_out, oldflp->saddr))
1007				goto source_ok;
1008			dev_put(dev_out);
1009			goto out;
1010		}
1011		rcu_read_lock();
1012		for_each_netdev_rcu(&init_net, dev) {
1013			if (!dev->dn_ptr)
1014				continue;
1015			if (!dn_dev_islocal(dev, oldflp->saddr))
1016				continue;
1017			if ((dev->flags & IFF_LOOPBACK) &&
1018			    oldflp->daddr &&
1019			    !dn_dev_islocal(dev, oldflp->daddr))
1020				continue;
1021
1022			dev_out = dev;
1023			break;
1024		}
1025		rcu_read_unlock();
1026		if (dev_out == NULL)
1027			goto out;
1028		dev_hold(dev_out);
1029source_ok:
1030		;
1031	}
1032
1033	/* No destination? Assume its local */
1034	if (!fld.daddr) {
1035		fld.daddr = fld.saddr;
1036
1037		if (dev_out)
1038			dev_put(dev_out);
1039		err = -EINVAL;
1040		dev_out = init_net.loopback_dev;
1041		if (!dev_out->dn_ptr)
1042			goto out;
1043		err = -EADDRNOTAVAIL;
1044		dev_hold(dev_out);
1045		if (!fld.daddr) {
1046			fld.daddr =
1047			fld.saddr = dnet_select_source(dev_out, 0,
1048						       RT_SCOPE_HOST);
1049			if (!fld.daddr)
1050				goto out;
1051		}
1052		fld.flowidn_oif = LOOPBACK_IFINDEX;
1053		res.type = RTN_LOCAL;
1054		goto make_route;
1055	}
1056
1057	if (decnet_debug_level & 16)
1058		printk(KERN_DEBUG
1059		       "dn_route_output_slow: initial checks complete."
1060		       " dst=%04x src=%04x oif=%d try_hard=%d\n",
1061		       le16_to_cpu(fld.daddr), le16_to_cpu(fld.saddr),
1062		       fld.flowidn_oif, try_hard);
1063
1064	/*
1065	 * N.B. If the kernel is compiled without router support then
1066	 * dn_fib_lookup() will evaluate to non-zero so this if () block
1067	 * will always be executed.
1068	 */
1069	err = -ESRCH;
1070	if (try_hard || (err = dn_fib_lookup(&fld, &res)) != 0) {
1071		struct dn_dev *dn_db;
1072		if (err != -ESRCH)
1073			goto out;
1074		/*
1075		 * Here the fallback is basically the standard algorithm for
1076		 * routing in endnodes which is described in the DECnet routing
1077		 * docs
1078		 *
1079		 * If we are not trying hard, look in neighbour cache.
1080		 * The result is tested to ensure that if a specific output
1081		 * device/source address was requested, then we honour that
1082		 * here
1083		 */
1084		if (!try_hard) {
1085			neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fld.daddr);
1086			if (neigh) {
1087				if ((oldflp->flowidn_oif &&
1088				    (neigh->dev->ifindex != oldflp->flowidn_oif)) ||
1089				    (oldflp->saddr &&
1090				    (!dn_dev_islocal(neigh->dev,
1091						     oldflp->saddr)))) {
1092					neigh_release(neigh);
1093					neigh = NULL;
1094				} else {
1095					if (dev_out)
1096						dev_put(dev_out);
1097					if (dn_dev_islocal(neigh->dev, fld.daddr)) {
1098						dev_out = init_net.loopback_dev;
1099						res.type = RTN_LOCAL;
1100					} else {
1101						dev_out = neigh->dev;
1102					}
1103					dev_hold(dev_out);
1104					goto select_source;
1105				}
1106			}
1107		}
1108
1109		/* Not there? Perhaps its a local address */
1110		if (dev_out == NULL)
1111			dev_out = dn_dev_get_default();
1112		err = -ENODEV;
1113		if (dev_out == NULL)
1114			goto out;
1115		dn_db = rcu_dereference_raw(dev_out->dn_ptr);
1116		if (!dn_db)
1117			goto e_inval;
1118		/* Possible improvement - check all devices for local addr */
1119		if (dn_dev_islocal(dev_out, fld.daddr)) {
1120			dev_put(dev_out);
1121			dev_out = init_net.loopback_dev;
1122			dev_hold(dev_out);
1123			res.type = RTN_LOCAL;
1124			goto select_source;
1125		}
1126		/* Not local either.... try sending it to the default router */
1127		neigh = neigh_clone(dn_db->router);
1128		BUG_ON(neigh && neigh->dev != dev_out);
1129
1130		/* Ok then, we assume its directly connected and move on */
1131select_source:
1132		if (neigh)
1133			gateway = ((struct dn_neigh *)neigh)->addr;
1134		if (gateway == 0)
1135			gateway = fld.daddr;
1136		if (fld.saddr == 0) {
1137			fld.saddr = dnet_select_source(dev_out, gateway,
1138						       res.type == RTN_LOCAL ?
1139						       RT_SCOPE_HOST :
1140						       RT_SCOPE_LINK);
1141			if (fld.saddr == 0 && res.type != RTN_LOCAL)
1142				goto e_addr;
1143		}
1144		fld.flowidn_oif = dev_out->ifindex;
1145		goto make_route;
1146	}
1147	free_res = 1;
1148
1149	if (res.type == RTN_NAT)
1150		goto e_inval;
1151
1152	if (res.type == RTN_LOCAL) {
1153		if (!fld.saddr)
1154			fld.saddr = fld.daddr;
1155		if (dev_out)
1156			dev_put(dev_out);
1157		dev_out = init_net.loopback_dev;
1158		dev_hold(dev_out);
1159		if (!dev_out->dn_ptr)
1160			goto e_inval;
1161		fld.flowidn_oif = dev_out->ifindex;
1162		if (res.fi)
1163			dn_fib_info_put(res.fi);
1164		res.fi = NULL;
1165		goto make_route;
1166	}
1167
1168	if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1169		dn_fib_select_multipath(&fld, &res);
1170
1171	/*
1172	 * We could add some logic to deal with default routes here and
1173	 * get rid of some of the special casing above.
1174	 */
1175
1176	if (!fld.saddr)
1177		fld.saddr = DN_FIB_RES_PREFSRC(res);
1178
1179	if (dev_out)
1180		dev_put(dev_out);
1181	dev_out = DN_FIB_RES_DEV(res);
1182	dev_hold(dev_out);
1183	fld.flowidn_oif = dev_out->ifindex;
1184	gateway = DN_FIB_RES_GW(res);
1185
1186make_route:
1187	if (dev_out->flags & IFF_LOOPBACK)
1188		flags |= RTCF_LOCAL;
1189
1190	rt = dst_alloc(&dn_dst_ops, dev_out, 1, DST_OBSOLETE_NONE, DST_HOST);
1191	if (rt == NULL)
1192		goto e_nobufs;
1193
 
1194	memset(&rt->fld, 0, sizeof(rt->fld));
1195	rt->fld.saddr        = oldflp->saddr;
1196	rt->fld.daddr        = oldflp->daddr;
1197	rt->fld.flowidn_oif  = oldflp->flowidn_oif;
1198	rt->fld.flowidn_iif  = 0;
1199	rt->fld.flowidn_mark = oldflp->flowidn_mark;
1200
1201	rt->rt_saddr      = fld.saddr;
1202	rt->rt_daddr      = fld.daddr;
1203	rt->rt_gateway    = gateway ? gateway : fld.daddr;
1204	rt->rt_local_src  = fld.saddr;
1205
1206	rt->rt_dst_map    = fld.daddr;
1207	rt->rt_src_map    = fld.saddr;
1208
1209	rt->n = neigh;
1210	neigh = NULL;
1211
1212	rt->dst.lastuse = jiffies;
1213	rt->dst.output  = dn_output;
1214	rt->dst.input   = dn_rt_bug;
1215	rt->rt_flags      = flags;
1216	if (flags & RTCF_LOCAL)
1217		rt->dst.input = dn_nsp_rx;
1218
1219	err = dn_rt_set_next_hop(rt, &res);
1220	if (err)
1221		goto e_neighbour;
1222
1223	hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
 
1224	dn_insert_route(rt, hash, (struct dn_route **)pprt);
1225
1226done:
1227	if (neigh)
1228		neigh_release(neigh);
1229	if (free_res)
1230		dn_fib_res_put(&res);
1231	if (dev_out)
1232		dev_put(dev_out);
1233out:
1234	return err;
1235
1236e_addr:
1237	err = -EADDRNOTAVAIL;
1238	goto done;
1239e_inval:
1240	err = -EINVAL;
1241	goto done;
1242e_nobufs:
1243	err = -ENOBUFS;
1244	goto done;
1245e_neighbour:
1246	dst_free(&rt->dst);
1247	goto e_nobufs;
1248}
1249
1250
1251/*
1252 * N.B. The flags may be moved into the flowi at some future stage.
1253 */
1254static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags)
1255{
1256	unsigned int hash = dn_hash(flp->saddr, flp->daddr);
1257	struct dn_route *rt = NULL;
1258
1259	if (!(flags & MSG_TRYHARD)) {
1260		rcu_read_lock_bh();
1261		for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
1262			rt = rcu_dereference_bh(rt->dst.dn_next)) {
1263			if ((flp->daddr == rt->fld.daddr) &&
1264			    (flp->saddr == rt->fld.saddr) &&
1265			    (flp->flowidn_mark == rt->fld.flowidn_mark) &&
1266			    dn_is_output_route(rt) &&
1267			    (rt->fld.flowidn_oif == flp->flowidn_oif)) {
1268				dst_use(&rt->dst, jiffies);
1269				rcu_read_unlock_bh();
1270				*pprt = &rt->dst;
1271				return 0;
1272			}
1273		}
1274		rcu_read_unlock_bh();
1275	}
1276
1277	return dn_route_output_slow(pprt, flp, flags);
1278}
1279
1280static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags)
1281{
1282	int err;
1283
1284	err = __dn_route_output_key(pprt, flp, flags);
1285	if (err == 0 && flp->flowidn_proto) {
1286		*pprt = xfrm_lookup(&init_net, *pprt,
1287				    flowidn_to_flowi(flp), NULL, 0);
1288		if (IS_ERR(*pprt)) {
1289			err = PTR_ERR(*pprt);
1290			*pprt = NULL;
1291		}
1292	}
1293	return err;
1294}
1295
1296int dn_route_output_sock(struct dst_entry __rcu **pprt, struct flowidn *fl, struct sock *sk, int flags)
1297{
1298	int err;
1299
1300	err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1301	if (err == 0 && fl->flowidn_proto) {
1302		*pprt = xfrm_lookup(&init_net, *pprt,
1303				    flowidn_to_flowi(fl), sk, 0);
1304		if (IS_ERR(*pprt)) {
1305			err = PTR_ERR(*pprt);
1306			*pprt = NULL;
1307		}
1308	}
1309	return err;
1310}
1311
1312static int dn_route_input_slow(struct sk_buff *skb)
1313{
1314	struct dn_route *rt = NULL;
1315	struct dn_skb_cb *cb = DN_SKB_CB(skb);
1316	struct net_device *in_dev = skb->dev;
1317	struct net_device *out_dev = NULL;
1318	struct dn_dev *dn_db;
1319	struct neighbour *neigh = NULL;
1320	unsigned int hash;
1321	int flags = 0;
1322	__le16 gateway = 0;
1323	__le16 local_src = 0;
1324	struct flowidn fld = {
1325		.daddr = cb->dst,
1326		.saddr = cb->src,
1327		.flowidn_scope = RT_SCOPE_UNIVERSE,
1328		.flowidn_mark = skb->mark,
1329		.flowidn_iif = skb->dev->ifindex,
1330	};
1331	struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1332	int err = -EINVAL;
1333	int free_res = 0;
1334
1335	dev_hold(in_dev);
1336
1337	if ((dn_db = rcu_dereference(in_dev->dn_ptr)) == NULL)
1338		goto out;
1339
1340	/* Zero source addresses are not allowed */
1341	if (fld.saddr == 0)
1342		goto out;
1343
1344	/*
1345	 * In this case we've just received a packet from a source
1346	 * outside ourselves pretending to come from us. We don't
1347	 * allow it any further to prevent routing loops, spoofing and
1348	 * other nasties. Loopback packets already have the dst attached
1349	 * so this only affects packets which have originated elsewhere.
1350	 */
1351	err  = -ENOTUNIQ;
1352	if (dn_dev_islocal(in_dev, cb->src))
1353		goto out;
1354
1355	err = dn_fib_lookup(&fld, &res);
1356	if (err) {
1357		if (err != -ESRCH)
1358			goto out;
1359		/*
1360		 * Is the destination us ?
1361		 */
1362		if (!dn_dev_islocal(in_dev, cb->dst))
1363			goto e_inval;
1364
1365		res.type = RTN_LOCAL;
1366	} else {
1367		__le16 src_map = fld.saddr;
1368		free_res = 1;
1369
1370		out_dev = DN_FIB_RES_DEV(res);
1371		if (out_dev == NULL) {
1372			net_crit_ratelimited("Bug in dn_route_input_slow() No output device\n");
1373			goto e_inval;
1374		}
1375		dev_hold(out_dev);
1376
1377		if (res.r)
1378			src_map = fld.saddr; /* no NAT support for now */
1379
1380		gateway = DN_FIB_RES_GW(res);
1381		if (res.type == RTN_NAT) {
1382			fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res);
1383			dn_fib_res_put(&res);
1384			free_res = 0;
1385			if (dn_fib_lookup(&fld, &res))
1386				goto e_inval;
1387			free_res = 1;
1388			if (res.type != RTN_UNICAST)
1389				goto e_inval;
1390			flags |= RTCF_DNAT;
1391			gateway = fld.daddr;
1392		}
1393		fld.saddr = src_map;
1394	}
1395
1396	switch(res.type) {
1397	case RTN_UNICAST:
1398		/*
1399		 * Forwarding check here, we only check for forwarding
1400		 * being turned off, if you want to only forward intra
1401		 * area, its up to you to set the routing tables up
1402		 * correctly.
1403		 */
1404		if (dn_db->parms.forwarding == 0)
1405			goto e_inval;
1406
1407		if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1408			dn_fib_select_multipath(&fld, &res);
1409
1410		/*
1411		 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1412		 * flag as a hint to set the intra-ethernet bit when
1413		 * forwarding. If we've got NAT in operation, we don't do
1414		 * this optimisation.
1415		 */
1416		if (out_dev == in_dev && !(flags & RTCF_NAT))
1417			flags |= RTCF_DOREDIRECT;
1418
1419		local_src = DN_FIB_RES_PREFSRC(res);
1420
1421	case RTN_BLACKHOLE:
1422	case RTN_UNREACHABLE:
1423		break;
1424	case RTN_LOCAL:
1425		flags |= RTCF_LOCAL;
1426		fld.saddr = cb->dst;
1427		fld.daddr = cb->src;
1428
1429		/* Routing tables gave us a gateway */
1430		if (gateway)
1431			goto make_route;
1432
1433		/* Packet was intra-ethernet, so we know its on-link */
1434		if (cb->rt_flags & DN_RT_F_IE) {
1435			gateway = cb->src;
1436			goto make_route;
1437		}
1438
1439		/* Use the default router if there is one */
1440		neigh = neigh_clone(dn_db->router);
1441		if (neigh) {
1442			gateway = ((struct dn_neigh *)neigh)->addr;
1443			goto make_route;
1444		}
1445
1446		/* Close eyes and pray */
1447		gateway = cb->src;
1448		goto make_route;
1449	default:
1450		goto e_inval;
1451	}
1452
1453make_route:
1454	rt = dst_alloc(&dn_dst_ops, out_dev, 0, DST_OBSOLETE_NONE, DST_HOST);
1455	if (rt == NULL)
1456		goto e_nobufs;
1457
 
1458	memset(&rt->fld, 0, sizeof(rt->fld));
1459	rt->rt_saddr      = fld.saddr;
1460	rt->rt_daddr      = fld.daddr;
1461	rt->rt_gateway    = fld.daddr;
1462	if (gateway)
1463		rt->rt_gateway = gateway;
1464	rt->rt_local_src  = local_src ? local_src : rt->rt_saddr;
1465
1466	rt->rt_dst_map    = fld.daddr;
1467	rt->rt_src_map    = fld.saddr;
1468
1469	rt->fld.saddr        = cb->src;
1470	rt->fld.daddr        = cb->dst;
1471	rt->fld.flowidn_oif  = 0;
1472	rt->fld.flowidn_iif  = in_dev->ifindex;
1473	rt->fld.flowidn_mark = fld.flowidn_mark;
1474
1475	rt->n = neigh;
1476	rt->dst.lastuse = jiffies;
1477	rt->dst.output = dn_rt_bug_out;
1478	switch (res.type) {
1479	case RTN_UNICAST:
1480		rt->dst.input = dn_forward;
1481		break;
1482	case RTN_LOCAL:
1483		rt->dst.output = dn_output;
1484		rt->dst.input = dn_nsp_rx;
1485		rt->dst.dev = in_dev;
1486		flags |= RTCF_LOCAL;
1487		break;
1488	default:
1489	case RTN_UNREACHABLE:
1490	case RTN_BLACKHOLE:
1491		rt->dst.input = dst_discard;
1492	}
1493	rt->rt_flags = flags;
1494
1495	err = dn_rt_set_next_hop(rt, &res);
1496	if (err)
1497		goto e_neighbour;
1498
1499	hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
 
1500	dn_insert_route(rt, hash, &rt);
1501	skb_dst_set(skb, &rt->dst);
1502
1503done:
1504	if (neigh)
1505		neigh_release(neigh);
1506	if (free_res)
1507		dn_fib_res_put(&res);
1508	dev_put(in_dev);
1509	if (out_dev)
1510		dev_put(out_dev);
1511out:
1512	return err;
1513
1514e_inval:
1515	err = -EINVAL;
1516	goto done;
1517
1518e_nobufs:
1519	err = -ENOBUFS;
1520	goto done;
1521
1522e_neighbour:
1523	dst_free(&rt->dst);
1524	goto done;
1525}
1526
1527static int dn_route_input(struct sk_buff *skb)
1528{
1529	struct dn_route *rt;
1530	struct dn_skb_cb *cb = DN_SKB_CB(skb);
1531	unsigned int hash = dn_hash(cb->src, cb->dst);
1532
1533	if (skb_dst(skb))
1534		return 0;
1535
1536	rcu_read_lock();
1537	for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1538	    rt = rcu_dereference(rt->dst.dn_next)) {
1539		if ((rt->fld.saddr == cb->src) &&
1540		    (rt->fld.daddr == cb->dst) &&
1541		    (rt->fld.flowidn_oif == 0) &&
1542		    (rt->fld.flowidn_mark == skb->mark) &&
1543		    (rt->fld.flowidn_iif == cb->iif)) {
1544			dst_use(&rt->dst, jiffies);
1545			rcu_read_unlock();
1546			skb_dst_set(skb, (struct dst_entry *)rt);
1547			return 0;
1548		}
1549	}
1550	rcu_read_unlock();
1551
1552	return dn_route_input_slow(skb);
1553}
1554
1555static int dn_rt_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
1556			   int event, int nowait, unsigned int flags)
1557{
1558	struct dn_route *rt = (struct dn_route *)skb_dst(skb);
1559	struct rtmsg *r;
1560	struct nlmsghdr *nlh;
1561	long expires;
1562
1563	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags);
1564	if (!nlh)
1565		return -EMSGSIZE;
1566
1567	r = nlmsg_data(nlh);
1568	r->rtm_family = AF_DECnet;
1569	r->rtm_dst_len = 16;
1570	r->rtm_src_len = 0;
1571	r->rtm_tos = 0;
1572	r->rtm_table = RT_TABLE_MAIN;
1573	r->rtm_type = rt->rt_type;
1574	r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1575	r->rtm_scope = RT_SCOPE_UNIVERSE;
1576	r->rtm_protocol = RTPROT_UNSPEC;
1577
1578	if (rt->rt_flags & RTCF_NOTIFY)
1579		r->rtm_flags |= RTM_F_NOTIFY;
1580
1581	if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN) < 0 ||
1582	    nla_put_le16(skb, RTA_DST, rt->rt_daddr) < 0)
1583		goto errout;
1584
1585	if (rt->fld.saddr) {
1586		r->rtm_src_len = 16;
1587		if (nla_put_le16(skb, RTA_SRC, rt->fld.saddr) < 0)
1588			goto errout;
1589	}
1590	if (rt->dst.dev &&
1591	    nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex) < 0)
1592		goto errout;
1593
1594	/*
1595	 * Note to self - change this if input routes reverse direction when
1596	 * they deal only with inputs and not with replies like they do
1597	 * currently.
1598	 */
1599	if (nla_put_le16(skb, RTA_PREFSRC, rt->rt_local_src) < 0)
1600		goto errout;
1601
1602	if (rt->rt_daddr != rt->rt_gateway &&
1603	    nla_put_le16(skb, RTA_GATEWAY, rt->rt_gateway) < 0)
1604		goto errout;
1605
1606	if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
1607		goto errout;
1608
1609	expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
1610	if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires,
1611			       rt->dst.error) < 0)
1612		goto errout;
1613
1614	if (dn_is_input_route(rt) &&
1615	    nla_put_u32(skb, RTA_IIF, rt->fld.flowidn_iif) < 0)
1616		goto errout;
1617
1618	nlmsg_end(skb, nlh);
1619	return 0;
1620
1621errout:
1622	nlmsg_cancel(skb, nlh);
1623	return -EMSGSIZE;
1624}
1625
1626const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
1627	[RTA_DST]		= { .type = NLA_U16 },
1628	[RTA_SRC]		= { .type = NLA_U16 },
1629	[RTA_IIF]		= { .type = NLA_U32 },
1630	[RTA_OIF]		= { .type = NLA_U32 },
1631	[RTA_GATEWAY]		= { .type = NLA_U16 },
1632	[RTA_PRIORITY]		= { .type = NLA_U32 },
1633	[RTA_PREFSRC]		= { .type = NLA_U16 },
1634	[RTA_METRICS]		= { .type = NLA_NESTED },
1635	[RTA_MULTIPATH]		= { .type = NLA_NESTED },
1636	[RTA_TABLE]		= { .type = NLA_U32 },
1637	[RTA_MARK]		= { .type = NLA_U32 },
1638};
1639
1640/*
1641 * This is called by both endnodes and routers now.
1642 */
1643static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 
1644{
1645	struct net *net = sock_net(in_skb->sk);
1646	struct rtmsg *rtm = nlmsg_data(nlh);
1647	struct dn_route *rt = NULL;
1648	struct dn_skb_cb *cb;
1649	int err;
1650	struct sk_buff *skb;
1651	struct flowidn fld;
1652	struct nlattr *tb[RTA_MAX+1];
1653
1654	if (!net_eq(net, &init_net))
1655		return -EINVAL;
1656
1657	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_dn_policy);
 
1658	if (err < 0)
1659		return err;
1660
1661	memset(&fld, 0, sizeof(fld));
1662	fld.flowidn_proto = DNPROTO_NSP;
1663
1664	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1665	if (skb == NULL)
1666		return -ENOBUFS;
1667	skb_reset_mac_header(skb);
1668	cb = DN_SKB_CB(skb);
1669
1670	if (tb[RTA_SRC])
1671		fld.saddr = nla_get_le16(tb[RTA_SRC]);
1672
1673	if (tb[RTA_DST])
1674		fld.daddr = nla_get_le16(tb[RTA_DST]);
1675
1676	if (tb[RTA_IIF])
1677		fld.flowidn_iif = nla_get_u32(tb[RTA_IIF]);
1678
1679	if (fld.flowidn_iif) {
1680		struct net_device *dev;
1681		dev = __dev_get_by_index(&init_net, fld.flowidn_iif);
1682		if (!dev || !dev->dn_ptr) {
1683			kfree_skb(skb);
1684			return -ENODEV;
1685		}
1686		skb->protocol = htons(ETH_P_DNA_RT);
1687		skb->dev = dev;
1688		cb->src = fld.saddr;
1689		cb->dst = fld.daddr;
1690		local_bh_disable();
1691		err = dn_route_input(skb);
1692		local_bh_enable();
1693		memset(cb, 0, sizeof(struct dn_skb_cb));
1694		rt = (struct dn_route *)skb_dst(skb);
1695		if (!err && -rt->dst.error)
1696			err = rt->dst.error;
1697	} else {
1698		if (tb[RTA_OIF])
1699			fld.flowidn_oif = nla_get_u32(tb[RTA_OIF]);
1700
1701		err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
1702	}
1703
1704	skb->dev = NULL;
1705	if (err)
1706		goto out_free;
1707	skb_dst_set(skb, &rt->dst);
1708	if (rtm->rtm_flags & RTM_F_NOTIFY)
1709		rt->rt_flags |= RTCF_NOTIFY;
1710
1711	err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1712	if (err < 0) {
1713		err = -EMSGSIZE;
1714		goto out_free;
1715	}
1716
1717	return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).portid);
1718
1719out_free:
1720	kfree_skb(skb);
1721	return err;
1722}
1723
1724/*
1725 * For routers, this is called from dn_fib_dump, but for endnodes its
1726 * called directly from the rtnetlink dispatch table.
1727 */
1728int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1729{
1730	struct net *net = sock_net(skb->sk);
1731	struct dn_route *rt;
1732	int h, s_h;
1733	int idx, s_idx;
1734	struct rtmsg *rtm;
1735
1736	if (!net_eq(net, &init_net))
1737		return 0;
1738
1739	if (nlmsg_len(cb->nlh) < sizeof(struct rtmsg))
1740		return -EINVAL;
1741
1742	rtm = nlmsg_data(cb->nlh);
1743	if (!(rtm->rtm_flags & RTM_F_CLONED))
1744		return 0;
1745
1746	s_h = cb->args[0];
1747	s_idx = idx = cb->args[1];
1748	for(h = 0; h <= dn_rt_hash_mask; h++) {
1749		if (h < s_h)
1750			continue;
1751		if (h > s_h)
1752			s_idx = 0;
1753		rcu_read_lock_bh();
1754		for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
1755			rt;
1756			rt = rcu_dereference_bh(rt->dst.dn_next), idx++) {
1757			if (idx < s_idx)
1758				continue;
1759			skb_dst_set(skb, dst_clone(&rt->dst));
1760			if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).portid,
1761					cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1762					1, NLM_F_MULTI) < 0) {
1763				skb_dst_drop(skb);
1764				rcu_read_unlock_bh();
1765				goto done;
1766			}
1767			skb_dst_drop(skb);
1768		}
1769		rcu_read_unlock_bh();
1770	}
1771
1772done:
1773	cb->args[0] = h;
1774	cb->args[1] = idx;
1775	return skb->len;
1776}
1777
1778#ifdef CONFIG_PROC_FS
1779struct dn_rt_cache_iter_state {
1780	int bucket;
1781};
1782
1783static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1784{
1785	struct dn_route *rt = NULL;
1786	struct dn_rt_cache_iter_state *s = seq->private;
1787
1788	for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1789		rcu_read_lock_bh();
1790		rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1791		if (rt)
1792			break;
1793		rcu_read_unlock_bh();
1794	}
1795	return rt;
1796}
1797
1798static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1799{
1800	struct dn_rt_cache_iter_state *s = seq->private;
1801
1802	rt = rcu_dereference_bh(rt->dst.dn_next);
1803	while (!rt) {
1804		rcu_read_unlock_bh();
1805		if (--s->bucket < 0)
1806			break;
1807		rcu_read_lock_bh();
1808		rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1809	}
1810	return rt;
1811}
1812
1813static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1814{
1815	struct dn_route *rt = dn_rt_cache_get_first(seq);
1816
1817	if (rt) {
1818		while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1819			--*pos;
1820	}
1821	return *pos ? NULL : rt;
1822}
1823
1824static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1825{
1826	struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1827	++*pos;
1828	return rt;
1829}
1830
1831static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1832{
1833	if (v)
1834		rcu_read_unlock_bh();
1835}
1836
1837static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1838{
1839	struct dn_route *rt = v;
1840	char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1841
1842	seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1843		   rt->dst.dev ? rt->dst.dev->name : "*",
1844		   dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
1845		   dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
1846		   atomic_read(&rt->dst.__refcnt),
1847		   rt->dst.__use, 0);
1848	return 0;
1849}
1850
1851static const struct seq_operations dn_rt_cache_seq_ops = {
1852	.start	= dn_rt_cache_seq_start,
1853	.next	= dn_rt_cache_seq_next,
1854	.stop	= dn_rt_cache_seq_stop,
1855	.show	= dn_rt_cache_seq_show,
1856};
1857
1858static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1859{
1860	return seq_open_private(file, &dn_rt_cache_seq_ops,
1861			sizeof(struct dn_rt_cache_iter_state));
1862}
1863
1864static const struct file_operations dn_rt_cache_seq_fops = {
1865	.owner	 = THIS_MODULE,
1866	.open	 = dn_rt_cache_seq_open,
1867	.read	 = seq_read,
1868	.llseek	 = seq_lseek,
1869	.release = seq_release_private,
1870};
1871
1872#endif /* CONFIG_PROC_FS */
1873
1874void __init dn_route_init(void)
1875{
1876	int i, goal, order;
1877
1878	dn_dst_ops.kmem_cachep =
1879		kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1880				  SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1881	dst_entries_init(&dn_dst_ops);
1882	setup_timer(&dn_route_timer, dn_dst_check_expire, 0);
1883	dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1884	add_timer(&dn_route_timer);
1885
1886	goal = totalram_pages >> (26 - PAGE_SHIFT);
1887
1888	for(order = 0; (1UL << order) < goal; order++)
1889		/* NOTHING */;
1890
1891	/*
1892	 * Only want 1024 entries max, since the table is very, very unlikely
1893	 * to be larger than that.
1894	 */
1895	while(order && ((((1UL << order) * PAGE_SIZE) /
1896				sizeof(struct dn_rt_hash_bucket)) >= 2048))
1897		order--;
1898
1899	do {
1900		dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1901			sizeof(struct dn_rt_hash_bucket);
1902		while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1903			dn_rt_hash_mask--;
1904		dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1905			__get_free_pages(GFP_ATOMIC, order);
1906	} while (dn_rt_hash_table == NULL && --order > 0);
1907
1908	if (!dn_rt_hash_table)
1909		panic("Failed to allocate DECnet route cache hash table\n");
1910
1911	printk(KERN_INFO
1912		"DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1913		dn_rt_hash_mask,
1914		(long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1915
1916	dn_rt_hash_mask--;
1917	for(i = 0; i <= dn_rt_hash_mask; i++) {
1918		spin_lock_init(&dn_rt_hash_table[i].lock);
1919		dn_rt_hash_table[i].chain = NULL;
1920	}
1921
1922	dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1923
1924	proc_create("decnet_cache", S_IRUGO, init_net.proc_net,
1925		    &dn_rt_cache_seq_fops);
1926
1927#ifdef CONFIG_DECNET_ROUTER
1928	rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1929		      dn_fib_dump, NULL);
1930#else
1931	rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1932		      dn_cache_dump, NULL);
1933#endif
1934}
1935
1936void __exit dn_route_cleanup(void)
1937{
1938	del_timer(&dn_route_timer);
1939	dn_run_flush(0);
1940
1941	remove_proc_entry("decnet_cache", init_net.proc_net);
1942	dst_entries_destroy(&dn_dst_ops);
1943}
1944