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
87 struct dn_rt_hash_bucket {
88 struct dn_route __rcu *chain;
89 spinlock_t lock;
90 };
91
92 extern struct neigh_table dn_neigh_table;
93
94
95 static unsigned char dn_hiord_addr[6] = {0xAA, 0x00, 0x04, 0x00, 0x00, 0x00};
96
97 static const int dn_rt_min_delay = 2 * HZ;
98 static const int dn_rt_max_delay = 10 * HZ;
99 static const int dn_rt_mtu_expires = 10 * 60 * HZ;
100
101 static unsigned long dn_rt_deadline;
102
103 static int dn_dst_gc(struct dst_ops *ops);
104 static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
105 static unsigned int dn_dst_default_advmss(const struct dst_entry *dst);
106 static unsigned int dn_dst_mtu(const struct dst_entry *dst);
107 static void dn_dst_destroy(struct dst_entry *);
108 static void dn_dst_ifdown(struct dst_entry *, struct net_device *dev, int how);
109 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
110 static void dn_dst_link_failure(struct sk_buff *);
111 static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
112 struct sk_buff *skb , u32 mtu,
113 bool confirm_neigh);
114 static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
115 struct sk_buff *skb);
116 static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
117 struct sk_buff *skb,
118 const void *daddr);
119 static int dn_route_input(struct sk_buff *);
120 static void dn_run_flush(struct timer_list *unused);
121
122 static struct dn_rt_hash_bucket *dn_rt_hash_table;
123 static unsigned int dn_rt_hash_mask;
124
125 static struct timer_list dn_route_timer;
126 static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush);
127 int decnet_dst_gc_interval = 2;
128
129 static 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
dn_dst_destroy(struct dst_entry * dst)146 static 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
dn_dst_ifdown(struct dst_entry * dst,struct net_device * dev,int how)155 static 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 = blackhole_netdev;
163 dev_hold(n->dev);
164 dev_put(dev);
165 }
166 }
167 }
168
dn_hash(__le16 src,__le16 dst)169 static __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
dn_dst_check_expire(struct timer_list * unused)178 static 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
dn_dst_gc(struct dst_ops * ops)211 static 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 */
dn_dst_update_pmtu(struct dst_entry * dst,struct sock * sk,struct sk_buff * skb,u32 mtu,bool confirm_neigh)253 static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
254 struct sk_buff *skb, u32 mtu,
255 bool confirm_neigh)
256 {
257 struct dn_route *rt = (struct dn_route *) dst;
258 struct neighbour *n = rt->n;
259 u32 min_mtu = 230;
260 struct dn_dev *dn;
261
262 dn = n ? rcu_dereference_raw(n->dev->dn_ptr) : NULL;
263
264 if (dn && dn->use_long == 0)
265 min_mtu -= 6;
266 else
267 min_mtu -= 21;
268
269 if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= min_mtu) {
270 if (!(dst_metric_locked(dst, RTAX_MTU))) {
271 dst_metric_set(dst, RTAX_MTU, mtu);
272 dst_set_expires(dst, dn_rt_mtu_expires);
273 }
274 if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
275 u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
276 u32 existing_mss = dst_metric_raw(dst, RTAX_ADVMSS);
277 if (!existing_mss || existing_mss > mss)
278 dst_metric_set(dst, RTAX_ADVMSS, mss);
279 }
280 }
281 }
282
dn_dst_redirect(struct dst_entry * dst,struct sock * sk,struct sk_buff * skb)283 static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
284 struct sk_buff *skb)
285 {
286 }
287
288 /*
289 * When a route has been marked obsolete. (e.g. routing cache flush)
290 */
dn_dst_check(struct dst_entry * dst,__u32 cookie)291 static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
292 {
293 return NULL;
294 }
295
dn_dst_negative_advice(struct dst_entry * dst)296 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
297 {
298 dst_release(dst);
299 return NULL;
300 }
301
dn_dst_link_failure(struct sk_buff * skb)302 static void dn_dst_link_failure(struct sk_buff *skb)
303 {
304 }
305
compare_keys(struct flowidn * fl1,struct flowidn * fl2)306 static inline int compare_keys(struct flowidn *fl1, struct flowidn *fl2)
307 {
308 return ((fl1->daddr ^ fl2->daddr) |
309 (fl1->saddr ^ fl2->saddr) |
310 (fl1->flowidn_mark ^ fl2->flowidn_mark) |
311 (fl1->flowidn_scope ^ fl2->flowidn_scope) |
312 (fl1->flowidn_oif ^ fl2->flowidn_oif) |
313 (fl1->flowidn_iif ^ fl2->flowidn_iif)) == 0;
314 }
315
dn_insert_route(struct dn_route * rt,unsigned int hash,struct dn_route ** rp)316 static int dn_insert_route(struct dn_route *rt, unsigned int hash, struct dn_route **rp)
317 {
318 struct dn_route *rth;
319 struct dn_route __rcu **rthp;
320 unsigned long now = jiffies;
321
322 rthp = &dn_rt_hash_table[hash].chain;
323
324 spin_lock_bh(&dn_rt_hash_table[hash].lock);
325 while ((rth = rcu_dereference_protected(*rthp,
326 lockdep_is_held(&dn_rt_hash_table[hash].lock))) != NULL) {
327 if (compare_keys(&rth->fld, &rt->fld)) {
328 /* Put it first */
329 *rthp = rth->dn_next;
330 rcu_assign_pointer(rth->dn_next,
331 dn_rt_hash_table[hash].chain);
332 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
333
334 dst_hold_and_use(&rth->dst, now);
335 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
336
337 dst_release_immediate(&rt->dst);
338 *rp = rth;
339 return 0;
340 }
341 rthp = &rth->dn_next;
342 }
343
344 rcu_assign_pointer(rt->dn_next, dn_rt_hash_table[hash].chain);
345 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
346
347 dst_hold_and_use(&rt->dst, now);
348 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
349 *rp = rt;
350 return 0;
351 }
352
dn_run_flush(struct timer_list * unused)353 static void dn_run_flush(struct timer_list *unused)
354 {
355 int i;
356 struct dn_route *rt, *next;
357
358 for (i = 0; i < dn_rt_hash_mask; i++) {
359 spin_lock_bh(&dn_rt_hash_table[i].lock);
360
361 rt = xchg((struct dn_route **)&dn_rt_hash_table[i].chain, NULL);
362 if (!rt)
363 goto nothing_to_declare;
364
365 for (; rt; rt = next) {
366 next = rcu_dereference_raw(rt->dn_next);
367 RCU_INIT_POINTER(rt->dn_next, NULL);
368 dst_dev_put(&rt->dst);
369 dst_release(&rt->dst);
370 }
371
372 nothing_to_declare:
373 spin_unlock_bh(&dn_rt_hash_table[i].lock);
374 }
375 }
376
377 static DEFINE_SPINLOCK(dn_rt_flush_lock);
378
dn_rt_cache_flush(int delay)379 void dn_rt_cache_flush(int delay)
380 {
381 unsigned long now = jiffies;
382 int user_mode = !in_interrupt();
383
384 if (delay < 0)
385 delay = dn_rt_min_delay;
386
387 spin_lock_bh(&dn_rt_flush_lock);
388
389 if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
390 long tmo = (long)(dn_rt_deadline - now);
391
392 if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
393 tmo = 0;
394
395 if (delay > tmo)
396 delay = tmo;
397 }
398
399 if (delay <= 0) {
400 spin_unlock_bh(&dn_rt_flush_lock);
401 dn_run_flush(NULL);
402 return;
403 }
404
405 if (dn_rt_deadline == 0)
406 dn_rt_deadline = now + dn_rt_max_delay;
407
408 dn_rt_flush_timer.expires = now + delay;
409 add_timer(&dn_rt_flush_timer);
410 spin_unlock_bh(&dn_rt_flush_lock);
411 }
412
413 /**
414 * dn_return_short - Return a short packet to its sender
415 * @skb: The packet to return
416 *
417 */
dn_return_short(struct sk_buff * skb)418 static int dn_return_short(struct sk_buff *skb)
419 {
420 struct dn_skb_cb *cb;
421 unsigned char *ptr;
422 __le16 *src;
423 __le16 *dst;
424
425 /* Add back headers */
426 skb_push(skb, skb->data - skb_network_header(skb));
427
428 skb = skb_unshare(skb, GFP_ATOMIC);
429 if (!skb)
430 return NET_RX_DROP;
431
432 cb = DN_SKB_CB(skb);
433 /* Skip packet length and point to flags */
434 ptr = skb->data + 2;
435 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
436
437 dst = (__le16 *)ptr;
438 ptr += 2;
439 src = (__le16 *)ptr;
440 ptr += 2;
441 *ptr = 0; /* Zero hop count */
442
443 swap(*src, *dst);
444
445 skb->pkt_type = PACKET_OUTGOING;
446 dn_rt_finish_output(skb, NULL, NULL);
447 return NET_RX_SUCCESS;
448 }
449
450 /**
451 * dn_return_long - Return a long packet to its sender
452 * @skb: The long format packet to return
453 *
454 */
dn_return_long(struct sk_buff * skb)455 static int dn_return_long(struct sk_buff *skb)
456 {
457 struct dn_skb_cb *cb;
458 unsigned char *ptr;
459 unsigned char *src_addr, *dst_addr;
460 unsigned char tmp[ETH_ALEN];
461
462 /* Add back all headers */
463 skb_push(skb, skb->data - skb_network_header(skb));
464
465 skb = skb_unshare(skb, GFP_ATOMIC);
466 if (!skb)
467 return NET_RX_DROP;
468
469 cb = DN_SKB_CB(skb);
470 /* Ignore packet length and point to flags */
471 ptr = skb->data + 2;
472
473 /* Skip padding */
474 if (*ptr & DN_RT_F_PF) {
475 char padlen = (*ptr & ~DN_RT_F_PF);
476 ptr += padlen;
477 }
478
479 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
480 ptr += 2;
481 dst_addr = ptr;
482 ptr += 8;
483 src_addr = ptr;
484 ptr += 6;
485 *ptr = 0; /* Zero hop count */
486
487 /* Swap source and destination */
488 memcpy(tmp, src_addr, ETH_ALEN);
489 memcpy(src_addr, dst_addr, ETH_ALEN);
490 memcpy(dst_addr, tmp, ETH_ALEN);
491
492 skb->pkt_type = PACKET_OUTGOING;
493 dn_rt_finish_output(skb, dst_addr, src_addr);
494 return NET_RX_SUCCESS;
495 }
496
497 /**
498 * dn_route_rx_packet - Try and find a route for an incoming packet
499 * @net: The applicable net namespace
500 * @sk: Socket packet transmitted on
501 * @skb: The packet to find a route for
502 *
503 * Returns: result of input function if route is found, error code otherwise
504 */
dn_route_rx_packet(struct net * net,struct sock * sk,struct sk_buff * skb)505 static int dn_route_rx_packet(struct net *net, struct sock *sk, struct sk_buff *skb)
506 {
507 struct dn_skb_cb *cb;
508 int err;
509
510 err = dn_route_input(skb);
511 if (err == 0)
512 return dst_input(skb);
513
514 cb = DN_SKB_CB(skb);
515 if (decnet_debug_level & 4) {
516 char *devname = skb->dev ? skb->dev->name : "???";
517
518 printk(KERN_DEBUG
519 "DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
520 (int)cb->rt_flags, devname, skb->len,
521 le16_to_cpu(cb->src), le16_to_cpu(cb->dst),
522 err, skb->pkt_type);
523 }
524
525 if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
526 switch (cb->rt_flags & DN_RT_PKT_MSK) {
527 case DN_RT_PKT_SHORT:
528 return dn_return_short(skb);
529 case DN_RT_PKT_LONG:
530 return dn_return_long(skb);
531 }
532 }
533
534 kfree_skb(skb);
535 return NET_RX_DROP;
536 }
537
dn_route_rx_long(struct sk_buff * skb)538 static int dn_route_rx_long(struct sk_buff *skb)
539 {
540 struct dn_skb_cb *cb = DN_SKB_CB(skb);
541 unsigned char *ptr = skb->data;
542
543 if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
544 goto drop_it;
545
546 skb_pull(skb, 20);
547 skb_reset_transport_header(skb);
548
549 /* Destination info */
550 ptr += 2;
551 cb->dst = dn_eth2dn(ptr);
552 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
553 goto drop_it;
554 ptr += 6;
555
556
557 /* Source info */
558 ptr += 2;
559 cb->src = dn_eth2dn(ptr);
560 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
561 goto drop_it;
562 ptr += 6;
563 /* Other junk */
564 ptr++;
565 cb->hops = *ptr++; /* Visit Count */
566
567 return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
568 &init_net, NULL, skb, skb->dev, NULL,
569 dn_route_rx_packet);
570
571 drop_it:
572 kfree_skb(skb);
573 return NET_RX_DROP;
574 }
575
576
577
dn_route_rx_short(struct sk_buff * skb)578 static int dn_route_rx_short(struct sk_buff *skb)
579 {
580 struct dn_skb_cb *cb = DN_SKB_CB(skb);
581 unsigned char *ptr = skb->data;
582
583 if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
584 goto drop_it;
585
586 skb_pull(skb, 5);
587 skb_reset_transport_header(skb);
588
589 cb->dst = *(__le16 *)ptr;
590 ptr += 2;
591 cb->src = *(__le16 *)ptr;
592 ptr += 2;
593 cb->hops = *ptr & 0x3f;
594
595 return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
596 &init_net, NULL, skb, skb->dev, NULL,
597 dn_route_rx_packet);
598
599 drop_it:
600 kfree_skb(skb);
601 return NET_RX_DROP;
602 }
603
dn_route_discard(struct net * net,struct sock * sk,struct sk_buff * skb)604 static int dn_route_discard(struct net *net, struct sock *sk, struct sk_buff *skb)
605 {
606 /*
607 * I know we drop the packet here, but that's considered success in
608 * this case
609 */
610 kfree_skb(skb);
611 return NET_RX_SUCCESS;
612 }
613
dn_route_ptp_hello(struct net * net,struct sock * sk,struct sk_buff * skb)614 static int dn_route_ptp_hello(struct net *net, struct sock *sk, struct sk_buff *skb)
615 {
616 dn_dev_hello(skb);
617 dn_neigh_pointopoint_hello(skb);
618 return NET_RX_SUCCESS;
619 }
620
dn_route_rcv(struct sk_buff * skb,struct net_device * dev,struct packet_type * pt,struct net_device * orig_dev)621 int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
622 {
623 struct dn_skb_cb *cb;
624 unsigned char flags = 0;
625 __u16 len = le16_to_cpu(*(__le16 *)skb->data);
626 struct dn_dev *dn = rcu_dereference(dev->dn_ptr);
627 unsigned char padlen = 0;
628
629 if (!net_eq(dev_net(dev), &init_net))
630 goto dump_it;
631
632 if (dn == NULL)
633 goto dump_it;
634
635 skb = skb_share_check(skb, GFP_ATOMIC);
636 if (!skb)
637 goto out;
638
639 if (!pskb_may_pull(skb, 3))
640 goto dump_it;
641
642 skb_pull(skb, 2);
643
644 if (len > skb->len)
645 goto dump_it;
646
647 skb_trim(skb, len);
648
649 flags = *skb->data;
650
651 cb = DN_SKB_CB(skb);
652 cb->stamp = jiffies;
653 cb->iif = dev->ifindex;
654
655 /*
656 * If we have padding, remove it.
657 */
658 if (flags & DN_RT_F_PF) {
659 padlen = flags & ~DN_RT_F_PF;
660 if (!pskb_may_pull(skb, padlen + 1))
661 goto dump_it;
662 skb_pull(skb, padlen);
663 flags = *skb->data;
664 }
665
666 skb_reset_network_header(skb);
667
668 /*
669 * Weed out future version DECnet
670 */
671 if (flags & DN_RT_F_VER)
672 goto dump_it;
673
674 cb->rt_flags = flags;
675
676 if (decnet_debug_level & 1)
677 printk(KERN_DEBUG
678 "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
679 (int)flags, dev->name, len, skb->len,
680 padlen);
681
682 if (flags & DN_RT_PKT_CNTL) {
683 if (unlikely(skb_linearize(skb)))
684 goto dump_it;
685
686 switch (flags & DN_RT_CNTL_MSK) {
687 case DN_RT_PKT_INIT:
688 dn_dev_init_pkt(skb);
689 break;
690 case DN_RT_PKT_VERI:
691 dn_dev_veri_pkt(skb);
692 break;
693 }
694
695 if (dn->parms.state != DN_DEV_S_RU)
696 goto dump_it;
697
698 switch (flags & DN_RT_CNTL_MSK) {
699 case DN_RT_PKT_HELO:
700 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
701 &init_net, NULL, skb, skb->dev, NULL,
702 dn_route_ptp_hello);
703
704 case DN_RT_PKT_L1RT:
705 case DN_RT_PKT_L2RT:
706 return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE,
707 &init_net, NULL, skb, skb->dev, NULL,
708 dn_route_discard);
709 case DN_RT_PKT_ERTH:
710 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
711 &init_net, NULL, skb, skb->dev, NULL,
712 dn_neigh_router_hello);
713
714 case DN_RT_PKT_EEDH:
715 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
716 &init_net, NULL, skb, skb->dev, NULL,
717 dn_neigh_endnode_hello);
718 }
719 } else {
720 if (dn->parms.state != DN_DEV_S_RU)
721 goto dump_it;
722
723 skb_pull(skb, 1); /* Pull flags */
724
725 switch (flags & DN_RT_PKT_MSK) {
726 case DN_RT_PKT_LONG:
727 return dn_route_rx_long(skb);
728 case DN_RT_PKT_SHORT:
729 return dn_route_rx_short(skb);
730 }
731 }
732
733 dump_it:
734 kfree_skb(skb);
735 out:
736 return NET_RX_DROP;
737 }
738
dn_output(struct net * net,struct sock * sk,struct sk_buff * skb)739 static int dn_output(struct net *net, struct sock *sk, struct sk_buff *skb)
740 {
741 struct dst_entry *dst = skb_dst(skb);
742 struct dn_route *rt = (struct dn_route *)dst;
743 struct net_device *dev = dst->dev;
744 struct dn_skb_cb *cb = DN_SKB_CB(skb);
745
746 int err = -EINVAL;
747
748 if (rt->n == NULL)
749 goto error;
750
751 skb->dev = dev;
752
753 cb->src = rt->rt_saddr;
754 cb->dst = rt->rt_daddr;
755
756 /*
757 * Always set the Intra-Ethernet bit on all outgoing packets
758 * originated on this node. Only valid flag from upper layers
759 * is return-to-sender-requested. Set hop count to 0 too.
760 */
761 cb->rt_flags &= ~DN_RT_F_RQR;
762 cb->rt_flags |= DN_RT_F_IE;
763 cb->hops = 0;
764
765 return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT,
766 &init_net, sk, skb, NULL, dev,
767 dn_to_neigh_output);
768
769 error:
770 net_dbg_ratelimited("dn_output: This should not happen\n");
771
772 kfree_skb(skb);
773
774 return err;
775 }
776
dn_forward(struct sk_buff * skb)777 static int dn_forward(struct sk_buff *skb)
778 {
779 struct dn_skb_cb *cb = DN_SKB_CB(skb);
780 struct dst_entry *dst = skb_dst(skb);
781 struct dn_dev *dn_db = rcu_dereference(dst->dev->dn_ptr);
782 struct dn_route *rt;
783 int header_len;
784 struct net_device *dev = skb->dev;
785
786 if (skb->pkt_type != PACKET_HOST)
787 goto drop;
788
789 /* Ensure that we have enough space for headers */
790 rt = (struct dn_route *)skb_dst(skb);
791 header_len = dn_db->use_long ? 21 : 6;
792 if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+header_len))
793 goto drop;
794
795 /*
796 * Hop count exceeded.
797 */
798 if (++cb->hops > 30)
799 goto drop;
800
801 skb->dev = rt->dst.dev;
802
803 /*
804 * If packet goes out same interface it came in on, then set
805 * the Intra-Ethernet bit. This has no effect for short
806 * packets, so we don't need to test for them here.
807 */
808 cb->rt_flags &= ~DN_RT_F_IE;
809 if (rt->rt_flags & RTCF_DOREDIRECT)
810 cb->rt_flags |= DN_RT_F_IE;
811
812 return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD,
813 &init_net, NULL, skb, dev, skb->dev,
814 dn_to_neigh_output);
815
816 drop:
817 kfree_skb(skb);
818 return NET_RX_DROP;
819 }
820
821 /*
822 * Used to catch bugs. This should never normally get
823 * called.
824 */
dn_rt_bug_out(struct net * net,struct sock * sk,struct sk_buff * skb)825 static int dn_rt_bug_out(struct net *net, struct sock *sk, struct sk_buff *skb)
826 {
827 struct dn_skb_cb *cb = DN_SKB_CB(skb);
828
829 net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
830 le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
831
832 kfree_skb(skb);
833
834 return NET_RX_DROP;
835 }
836
dn_rt_bug(struct sk_buff * skb)837 static int dn_rt_bug(struct sk_buff *skb)
838 {
839 struct dn_skb_cb *cb = DN_SKB_CB(skb);
840
841 net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
842 le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
843
844 kfree_skb(skb);
845
846 return NET_RX_DROP;
847 }
848
dn_dst_default_advmss(const struct dst_entry * dst)849 static unsigned int dn_dst_default_advmss(const struct dst_entry *dst)
850 {
851 return dn_mss_from_pmtu(dst->dev, dst_mtu(dst));
852 }
853
dn_dst_mtu(const struct dst_entry * dst)854 static unsigned int dn_dst_mtu(const struct dst_entry *dst)
855 {
856 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
857
858 return mtu ? : dst->dev->mtu;
859 }
860
dn_dst_neigh_lookup(const struct dst_entry * dst,struct sk_buff * skb,const void * daddr)861 static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
862 struct sk_buff *skb,
863 const void *daddr)
864 {
865 return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
866 }
867
dn_rt_set_next_hop(struct dn_route * rt,struct dn_fib_res * res)868 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
869 {
870 struct dn_fib_info *fi = res->fi;
871 struct net_device *dev = rt->dst.dev;
872 unsigned int mss_metric;
873 struct neighbour *n;
874
875 if (fi) {
876 if (DN_FIB_RES_GW(*res) &&
877 DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
878 rt->rt_gateway = DN_FIB_RES_GW(*res);
879 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
880 }
881 rt->rt_type = res->type;
882
883 if (dev != NULL && rt->n == NULL) {
884 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
885 if (IS_ERR(n))
886 return PTR_ERR(n);
887 rt->n = n;
888 }
889
890 if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
891 dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
892 mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
893 if (mss_metric) {
894 unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
895 if (mss_metric > mss)
896 dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
897 }
898 return 0;
899 }
900
dn_match_addr(__le16 addr1,__le16 addr2)901 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
902 {
903 __u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
904 int match = 16;
905 while (tmp) {
906 tmp >>= 1;
907 match--;
908 }
909 return match;
910 }
911
dnet_select_source(const struct net_device * dev,__le16 daddr,int scope)912 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
913 {
914 __le16 saddr = 0;
915 struct dn_dev *dn_db;
916 struct dn_ifaddr *ifa;
917 int best_match = 0;
918 int ret;
919
920 rcu_read_lock();
921 dn_db = rcu_dereference(dev->dn_ptr);
922 for (ifa = rcu_dereference(dn_db->ifa_list);
923 ifa != NULL;
924 ifa = rcu_dereference(ifa->ifa_next)) {
925 if (ifa->ifa_scope > scope)
926 continue;
927 if (!daddr) {
928 saddr = ifa->ifa_local;
929 break;
930 }
931 ret = dn_match_addr(daddr, ifa->ifa_local);
932 if (ret > best_match)
933 saddr = ifa->ifa_local;
934 if (best_match == 0)
935 saddr = ifa->ifa_local;
936 }
937 rcu_read_unlock();
938
939 return saddr;
940 }
941
__dn_fib_res_prefsrc(struct dn_fib_res * res)942 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
943 {
944 return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
945 }
946
dn_fib_rules_map_destination(__le16 daddr,struct dn_fib_res * res)947 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
948 {
949 __le16 mask = dnet_make_mask(res->prefixlen);
950 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
951 }
952
dn_route_output_slow(struct dst_entry ** pprt,const struct flowidn * oldflp,int try_hard)953 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard)
954 {
955 struct flowidn fld = {
956 .daddr = oldflp->daddr,
957 .saddr = oldflp->saddr,
958 .flowidn_scope = RT_SCOPE_UNIVERSE,
959 .flowidn_mark = oldflp->flowidn_mark,
960 .flowidn_iif = LOOPBACK_IFINDEX,
961 .flowidn_oif = oldflp->flowidn_oif,
962 };
963 struct dn_route *rt = NULL;
964 struct net_device *dev_out = NULL, *dev;
965 struct neighbour *neigh = NULL;
966 unsigned int hash;
967 unsigned int flags = 0;
968 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
969 int err;
970 int free_res = 0;
971 __le16 gateway = 0;
972
973 if (decnet_debug_level & 16)
974 printk(KERN_DEBUG
975 "dn_route_output_slow: dst=%04x src=%04x mark=%d"
976 " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
977 le16_to_cpu(oldflp->saddr),
978 oldflp->flowidn_mark, LOOPBACK_IFINDEX,
979 oldflp->flowidn_oif);
980
981 /* If we have an output interface, verify its a DECnet device */
982 if (oldflp->flowidn_oif) {
983 dev_out = dev_get_by_index(&init_net, oldflp->flowidn_oif);
984 err = -ENODEV;
985 if (dev_out && dev_out->dn_ptr == NULL) {
986 dev_put(dev_out);
987 dev_out = NULL;
988 }
989 if (dev_out == NULL)
990 goto out;
991 }
992
993 /* If we have a source address, verify that its a local address */
994 if (oldflp->saddr) {
995 err = -EADDRNOTAVAIL;
996
997 if (dev_out) {
998 if (dn_dev_islocal(dev_out, oldflp->saddr))
999 goto source_ok;
1000 dev_put(dev_out);
1001 goto out;
1002 }
1003 rcu_read_lock();
1004 for_each_netdev_rcu(&init_net, dev) {
1005 if (!dev->dn_ptr)
1006 continue;
1007 if (!dn_dev_islocal(dev, oldflp->saddr))
1008 continue;
1009 if ((dev->flags & IFF_LOOPBACK) &&
1010 oldflp->daddr &&
1011 !dn_dev_islocal(dev, oldflp->daddr))
1012 continue;
1013
1014 dev_out = dev;
1015 break;
1016 }
1017 rcu_read_unlock();
1018 if (dev_out == NULL)
1019 goto out;
1020 dev_hold(dev_out);
1021 source_ok:
1022 ;
1023 }
1024
1025 /* No destination? Assume its local */
1026 if (!fld.daddr) {
1027 fld.daddr = fld.saddr;
1028
1029 dev_put(dev_out);
1030 err = -EINVAL;
1031 dev_out = init_net.loopback_dev;
1032 if (!dev_out->dn_ptr)
1033 goto out;
1034 err = -EADDRNOTAVAIL;
1035 dev_hold(dev_out);
1036 if (!fld.daddr) {
1037 fld.daddr =
1038 fld.saddr = dnet_select_source(dev_out, 0,
1039 RT_SCOPE_HOST);
1040 if (!fld.daddr)
1041 goto done;
1042 }
1043 fld.flowidn_oif = LOOPBACK_IFINDEX;
1044 res.type = RTN_LOCAL;
1045 goto make_route;
1046 }
1047
1048 if (decnet_debug_level & 16)
1049 printk(KERN_DEBUG
1050 "dn_route_output_slow: initial checks complete."
1051 " dst=%04x src=%04x oif=%d try_hard=%d\n",
1052 le16_to_cpu(fld.daddr), le16_to_cpu(fld.saddr),
1053 fld.flowidn_oif, try_hard);
1054
1055 /*
1056 * N.B. If the kernel is compiled without router support then
1057 * dn_fib_lookup() will evaluate to non-zero so this if () block
1058 * will always be executed.
1059 */
1060 err = -ESRCH;
1061 if (try_hard || (err = dn_fib_lookup(&fld, &res)) != 0) {
1062 struct dn_dev *dn_db;
1063 if (err != -ESRCH)
1064 goto out;
1065 /*
1066 * Here the fallback is basically the standard algorithm for
1067 * routing in endnodes which is described in the DECnet routing
1068 * docs
1069 *
1070 * If we are not trying hard, look in neighbour cache.
1071 * The result is tested to ensure that if a specific output
1072 * device/source address was requested, then we honour that
1073 * here
1074 */
1075 if (!try_hard) {
1076 neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fld.daddr);
1077 if (neigh) {
1078 if ((oldflp->flowidn_oif &&
1079 (neigh->dev->ifindex != oldflp->flowidn_oif)) ||
1080 (oldflp->saddr &&
1081 (!dn_dev_islocal(neigh->dev,
1082 oldflp->saddr)))) {
1083 neigh_release(neigh);
1084 neigh = NULL;
1085 } else {
1086 dev_put(dev_out);
1087 if (dn_dev_islocal(neigh->dev, fld.daddr)) {
1088 dev_out = init_net.loopback_dev;
1089 res.type = RTN_LOCAL;
1090 } else {
1091 dev_out = neigh->dev;
1092 }
1093 dev_hold(dev_out);
1094 goto select_source;
1095 }
1096 }
1097 }
1098
1099 /* Not there? Perhaps its a local address */
1100 if (dev_out == NULL)
1101 dev_out = dn_dev_get_default();
1102 err = -ENODEV;
1103 if (dev_out == NULL)
1104 goto out;
1105 dn_db = rcu_dereference_raw(dev_out->dn_ptr);
1106 if (!dn_db)
1107 goto e_inval;
1108 /* Possible improvement - check all devices for local addr */
1109 if (dn_dev_islocal(dev_out, fld.daddr)) {
1110 dev_put(dev_out);
1111 dev_out = init_net.loopback_dev;
1112 dev_hold(dev_out);
1113 res.type = RTN_LOCAL;
1114 goto select_source;
1115 }
1116 /* Not local either.... try sending it to the default router */
1117 neigh = neigh_clone(dn_db->router);
1118 BUG_ON(neigh && neigh->dev != dev_out);
1119
1120 /* Ok then, we assume its directly connected and move on */
1121 select_source:
1122 if (neigh)
1123 gateway = container_of(neigh, struct dn_neigh, n)->addr;
1124 if (gateway == 0)
1125 gateway = fld.daddr;
1126 if (fld.saddr == 0) {
1127 fld.saddr = dnet_select_source(dev_out, gateway,
1128 res.type == RTN_LOCAL ?
1129 RT_SCOPE_HOST :
1130 RT_SCOPE_LINK);
1131 if (fld.saddr == 0 && res.type != RTN_LOCAL)
1132 goto e_addr;
1133 }
1134 fld.flowidn_oif = dev_out->ifindex;
1135 goto make_route;
1136 }
1137 free_res = 1;
1138
1139 if (res.type == RTN_NAT)
1140 goto e_inval;
1141
1142 if (res.type == RTN_LOCAL) {
1143 if (!fld.saddr)
1144 fld.saddr = fld.daddr;
1145 dev_put(dev_out);
1146 dev_out = init_net.loopback_dev;
1147 dev_hold(dev_out);
1148 if (!dev_out->dn_ptr)
1149 goto e_inval;
1150 fld.flowidn_oif = dev_out->ifindex;
1151 if (res.fi)
1152 dn_fib_info_put(res.fi);
1153 res.fi = NULL;
1154 goto make_route;
1155 }
1156
1157 if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1158 dn_fib_select_multipath(&fld, &res);
1159
1160 /*
1161 * We could add some logic to deal with default routes here and
1162 * get rid of some of the special casing above.
1163 */
1164
1165 if (!fld.saddr)
1166 fld.saddr = DN_FIB_RES_PREFSRC(res);
1167
1168 dev_put(dev_out);
1169 dev_out = DN_FIB_RES_DEV(res);
1170 dev_hold(dev_out);
1171 fld.flowidn_oif = dev_out->ifindex;
1172 gateway = DN_FIB_RES_GW(res);
1173
1174 make_route:
1175 if (dev_out->flags & IFF_LOOPBACK)
1176 flags |= RTCF_LOCAL;
1177
1178 rt = dst_alloc(&dn_dst_ops, dev_out, 0, DST_OBSOLETE_NONE, 0);
1179 if (rt == NULL)
1180 goto e_nobufs;
1181
1182 rt->dn_next = NULL;
1183 memset(&rt->fld, 0, sizeof(rt->fld));
1184 rt->fld.saddr = oldflp->saddr;
1185 rt->fld.daddr = oldflp->daddr;
1186 rt->fld.flowidn_oif = oldflp->flowidn_oif;
1187 rt->fld.flowidn_iif = 0;
1188 rt->fld.flowidn_mark = oldflp->flowidn_mark;
1189
1190 rt->rt_saddr = fld.saddr;
1191 rt->rt_daddr = fld.daddr;
1192 rt->rt_gateway = gateway ? gateway : fld.daddr;
1193 rt->rt_local_src = fld.saddr;
1194
1195 rt->rt_dst_map = fld.daddr;
1196 rt->rt_src_map = fld.saddr;
1197
1198 rt->n = neigh;
1199 neigh = NULL;
1200
1201 rt->dst.lastuse = jiffies;
1202 rt->dst.output = dn_output;
1203 rt->dst.input = dn_rt_bug;
1204 rt->rt_flags = flags;
1205 if (flags & RTCF_LOCAL)
1206 rt->dst.input = dn_nsp_rx;
1207
1208 err = dn_rt_set_next_hop(rt, &res);
1209 if (err)
1210 goto e_neighbour;
1211
1212 hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1213 /* dn_insert_route() increments dst->__refcnt */
1214 dn_insert_route(rt, hash, (struct dn_route **)pprt);
1215
1216 done:
1217 if (neigh)
1218 neigh_release(neigh);
1219 if (free_res)
1220 dn_fib_res_put(&res);
1221 dev_put(dev_out);
1222 out:
1223 return err;
1224
1225 e_addr:
1226 err = -EADDRNOTAVAIL;
1227 goto done;
1228 e_inval:
1229 err = -EINVAL;
1230 goto done;
1231 e_nobufs:
1232 err = -ENOBUFS;
1233 goto done;
1234 e_neighbour:
1235 dst_release_immediate(&rt->dst);
1236 goto e_nobufs;
1237 }
1238
1239
1240 /*
1241 * N.B. The flags may be moved into the flowi at some future stage.
1242 */
__dn_route_output_key(struct dst_entry ** pprt,const struct flowidn * flp,int flags)1243 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags)
1244 {
1245 unsigned int hash = dn_hash(flp->saddr, flp->daddr);
1246 struct dn_route *rt = NULL;
1247
1248 if (!(flags & MSG_TRYHARD)) {
1249 rcu_read_lock_bh();
1250 for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
1251 rt = rcu_dereference_bh(rt->dn_next)) {
1252 if ((flp->daddr == rt->fld.daddr) &&
1253 (flp->saddr == rt->fld.saddr) &&
1254 (flp->flowidn_mark == rt->fld.flowidn_mark) &&
1255 dn_is_output_route(rt) &&
1256 (rt->fld.flowidn_oif == flp->flowidn_oif)) {
1257 dst_hold_and_use(&rt->dst, jiffies);
1258 rcu_read_unlock_bh();
1259 *pprt = &rt->dst;
1260 return 0;
1261 }
1262 }
1263 rcu_read_unlock_bh();
1264 }
1265
1266 return dn_route_output_slow(pprt, flp, flags);
1267 }
1268
dn_route_output_key(struct dst_entry ** pprt,struct flowidn * flp,int flags)1269 static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags)
1270 {
1271 int err;
1272
1273 err = __dn_route_output_key(pprt, flp, flags);
1274 if (err == 0 && flp->flowidn_proto) {
1275 *pprt = xfrm_lookup(&init_net, *pprt,
1276 flowidn_to_flowi(flp), NULL, 0);
1277 if (IS_ERR(*pprt)) {
1278 err = PTR_ERR(*pprt);
1279 *pprt = NULL;
1280 }
1281 }
1282 return err;
1283 }
1284
dn_route_output_sock(struct dst_entry __rcu ** pprt,struct flowidn * fl,struct sock * sk,int flags)1285 int dn_route_output_sock(struct dst_entry __rcu **pprt, struct flowidn *fl, struct sock *sk, int flags)
1286 {
1287 int err;
1288
1289 err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1290 if (err == 0 && fl->flowidn_proto) {
1291 *pprt = xfrm_lookup(&init_net, *pprt,
1292 flowidn_to_flowi(fl), sk, 0);
1293 if (IS_ERR(*pprt)) {
1294 err = PTR_ERR(*pprt);
1295 *pprt = NULL;
1296 }
1297 }
1298 return err;
1299 }
1300
dn_route_input_slow(struct sk_buff * skb)1301 static int dn_route_input_slow(struct sk_buff *skb)
1302 {
1303 struct dn_route *rt = NULL;
1304 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1305 struct net_device *in_dev = skb->dev;
1306 struct net_device *out_dev = NULL;
1307 struct dn_dev *dn_db;
1308 struct neighbour *neigh = NULL;
1309 unsigned int hash;
1310 int flags = 0;
1311 __le16 gateway = 0;
1312 __le16 local_src = 0;
1313 struct flowidn fld = {
1314 .daddr = cb->dst,
1315 .saddr = cb->src,
1316 .flowidn_scope = RT_SCOPE_UNIVERSE,
1317 .flowidn_mark = skb->mark,
1318 .flowidn_iif = skb->dev->ifindex,
1319 };
1320 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1321 int err = -EINVAL;
1322 int free_res = 0;
1323
1324 dev_hold(in_dev);
1325
1326 dn_db = rcu_dereference(in_dev->dn_ptr);
1327 if (!dn_db)
1328 goto out;
1329
1330 /* Zero source addresses are not allowed */
1331 if (fld.saddr == 0)
1332 goto out;
1333
1334 /*
1335 * In this case we've just received a packet from a source
1336 * outside ourselves pretending to come from us. We don't
1337 * allow it any further to prevent routing loops, spoofing and
1338 * other nasties. Loopback packets already have the dst attached
1339 * so this only affects packets which have originated elsewhere.
1340 */
1341 err = -ENOTUNIQ;
1342 if (dn_dev_islocal(in_dev, cb->src))
1343 goto out;
1344
1345 err = dn_fib_lookup(&fld, &res);
1346 if (err) {
1347 if (err != -ESRCH)
1348 goto out;
1349 /*
1350 * Is the destination us ?
1351 */
1352 if (!dn_dev_islocal(in_dev, cb->dst))
1353 goto e_inval;
1354
1355 res.type = RTN_LOCAL;
1356 } else {
1357 __le16 src_map = fld.saddr;
1358 free_res = 1;
1359
1360 out_dev = DN_FIB_RES_DEV(res);
1361 if (out_dev == NULL) {
1362 net_crit_ratelimited("Bug in dn_route_input_slow() No output device\n");
1363 goto e_inval;
1364 }
1365 dev_hold(out_dev);
1366
1367 if (res.r)
1368 src_map = fld.saddr; /* no NAT support for now */
1369
1370 gateway = DN_FIB_RES_GW(res);
1371 if (res.type == RTN_NAT) {
1372 fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res);
1373 dn_fib_res_put(&res);
1374 free_res = 0;
1375 if (dn_fib_lookup(&fld, &res))
1376 goto e_inval;
1377 free_res = 1;
1378 if (res.type != RTN_UNICAST)
1379 goto e_inval;
1380 flags |= RTCF_DNAT;
1381 gateway = fld.daddr;
1382 }
1383 fld.saddr = src_map;
1384 }
1385
1386 switch (res.type) {
1387 case RTN_UNICAST:
1388 /*
1389 * Forwarding check here, we only check for forwarding
1390 * being turned off, if you want to only forward intra
1391 * area, its up to you to set the routing tables up
1392 * correctly.
1393 */
1394 if (dn_db->parms.forwarding == 0)
1395 goto e_inval;
1396
1397 if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1398 dn_fib_select_multipath(&fld, &res);
1399
1400 /*
1401 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1402 * flag as a hint to set the intra-ethernet bit when
1403 * forwarding. If we've got NAT in operation, we don't do
1404 * this optimisation.
1405 */
1406 if (out_dev == in_dev && !(flags & RTCF_NAT))
1407 flags |= RTCF_DOREDIRECT;
1408
1409 local_src = DN_FIB_RES_PREFSRC(res);
1410 break;
1411 case RTN_BLACKHOLE:
1412 case RTN_UNREACHABLE:
1413 break;
1414 case RTN_LOCAL:
1415 flags |= RTCF_LOCAL;
1416 fld.saddr = cb->dst;
1417 fld.daddr = cb->src;
1418
1419 /* Routing tables gave us a gateway */
1420 if (gateway)
1421 goto make_route;
1422
1423 /* Packet was intra-ethernet, so we know its on-link */
1424 if (cb->rt_flags & DN_RT_F_IE) {
1425 gateway = cb->src;
1426 goto make_route;
1427 }
1428
1429 /* Use the default router if there is one */
1430 neigh = neigh_clone(dn_db->router);
1431 if (neigh) {
1432 gateway = container_of(neigh, struct dn_neigh, n)->addr;
1433 goto make_route;
1434 }
1435
1436 /* Close eyes and pray */
1437 gateway = cb->src;
1438 goto make_route;
1439 default:
1440 goto e_inval;
1441 }
1442
1443 make_route:
1444 rt = dst_alloc(&dn_dst_ops, out_dev, 1, DST_OBSOLETE_NONE, 0);
1445 if (rt == NULL)
1446 goto e_nobufs;
1447
1448 rt->dn_next = NULL;
1449 memset(&rt->fld, 0, sizeof(rt->fld));
1450 rt->rt_saddr = fld.saddr;
1451 rt->rt_daddr = fld.daddr;
1452 rt->rt_gateway = fld.daddr;
1453 if (gateway)
1454 rt->rt_gateway = gateway;
1455 rt->rt_local_src = local_src ? local_src : rt->rt_saddr;
1456
1457 rt->rt_dst_map = fld.daddr;
1458 rt->rt_src_map = fld.saddr;
1459
1460 rt->fld.saddr = cb->src;
1461 rt->fld.daddr = cb->dst;
1462 rt->fld.flowidn_oif = 0;
1463 rt->fld.flowidn_iif = in_dev->ifindex;
1464 rt->fld.flowidn_mark = fld.flowidn_mark;
1465
1466 rt->n = neigh;
1467 rt->dst.lastuse = jiffies;
1468 rt->dst.output = dn_rt_bug_out;
1469 switch (res.type) {
1470 case RTN_UNICAST:
1471 rt->dst.input = dn_forward;
1472 break;
1473 case RTN_LOCAL:
1474 rt->dst.output = dn_output;
1475 rt->dst.input = dn_nsp_rx;
1476 rt->dst.dev = in_dev;
1477 flags |= RTCF_LOCAL;
1478 break;
1479 default:
1480 case RTN_UNREACHABLE:
1481 case RTN_BLACKHOLE:
1482 rt->dst.input = dst_discard;
1483 }
1484 rt->rt_flags = flags;
1485
1486 err = dn_rt_set_next_hop(rt, &res);
1487 if (err)
1488 goto e_neighbour;
1489
1490 hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1491 /* dn_insert_route() increments dst->__refcnt */
1492 dn_insert_route(rt, hash, &rt);
1493 skb_dst_set(skb, &rt->dst);
1494
1495 done:
1496 if (neigh)
1497 neigh_release(neigh);
1498 if (free_res)
1499 dn_fib_res_put(&res);
1500 dev_put(in_dev);
1501 dev_put(out_dev);
1502 out:
1503 return err;
1504
1505 e_inval:
1506 err = -EINVAL;
1507 goto done;
1508
1509 e_nobufs:
1510 err = -ENOBUFS;
1511 goto done;
1512
1513 e_neighbour:
1514 dst_release_immediate(&rt->dst);
1515 goto done;
1516 }
1517
dn_route_input(struct sk_buff * skb)1518 static int dn_route_input(struct sk_buff *skb)
1519 {
1520 struct dn_route *rt;
1521 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1522 unsigned int hash = dn_hash(cb->src, cb->dst);
1523
1524 if (skb_dst(skb))
1525 return 0;
1526
1527 rcu_read_lock();
1528 for (rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1529 rt = rcu_dereference(rt->dn_next)) {
1530 if ((rt->fld.saddr == cb->src) &&
1531 (rt->fld.daddr == cb->dst) &&
1532 (rt->fld.flowidn_oif == 0) &&
1533 (rt->fld.flowidn_mark == skb->mark) &&
1534 (rt->fld.flowidn_iif == cb->iif)) {
1535 dst_hold_and_use(&rt->dst, jiffies);
1536 rcu_read_unlock();
1537 skb_dst_set(skb, (struct dst_entry *)rt);
1538 return 0;
1539 }
1540 }
1541 rcu_read_unlock();
1542
1543 return dn_route_input_slow(skb);
1544 }
1545
dn_rt_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int event,int nowait,unsigned int flags)1546 static int dn_rt_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
1547 int event, int nowait, unsigned int flags)
1548 {
1549 struct dn_route *rt = (struct dn_route *)skb_dst(skb);
1550 struct rtmsg *r;
1551 struct nlmsghdr *nlh;
1552 long expires;
1553
1554 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags);
1555 if (!nlh)
1556 return -EMSGSIZE;
1557
1558 r = nlmsg_data(nlh);
1559 r->rtm_family = AF_DECnet;
1560 r->rtm_dst_len = 16;
1561 r->rtm_src_len = 0;
1562 r->rtm_tos = 0;
1563 r->rtm_table = RT_TABLE_MAIN;
1564 r->rtm_type = rt->rt_type;
1565 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1566 r->rtm_scope = RT_SCOPE_UNIVERSE;
1567 r->rtm_protocol = RTPROT_UNSPEC;
1568
1569 if (rt->rt_flags & RTCF_NOTIFY)
1570 r->rtm_flags |= RTM_F_NOTIFY;
1571
1572 if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN) < 0 ||
1573 nla_put_le16(skb, RTA_DST, rt->rt_daddr) < 0)
1574 goto errout;
1575
1576 if (rt->fld.saddr) {
1577 r->rtm_src_len = 16;
1578 if (nla_put_le16(skb, RTA_SRC, rt->fld.saddr) < 0)
1579 goto errout;
1580 }
1581 if (rt->dst.dev &&
1582 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex) < 0)
1583 goto errout;
1584
1585 /*
1586 * Note to self - change this if input routes reverse direction when
1587 * they deal only with inputs and not with replies like they do
1588 * currently.
1589 */
1590 if (nla_put_le16(skb, RTA_PREFSRC, rt->rt_local_src) < 0)
1591 goto errout;
1592
1593 if (rt->rt_daddr != rt->rt_gateway &&
1594 nla_put_le16(skb, RTA_GATEWAY, rt->rt_gateway) < 0)
1595 goto errout;
1596
1597 if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
1598 goto errout;
1599
1600 expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
1601 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires,
1602 rt->dst.error) < 0)
1603 goto errout;
1604
1605 if (dn_is_input_route(rt) &&
1606 nla_put_u32(skb, RTA_IIF, rt->fld.flowidn_iif) < 0)
1607 goto errout;
1608
1609 nlmsg_end(skb, nlh);
1610 return 0;
1611
1612 errout:
1613 nlmsg_cancel(skb, nlh);
1614 return -EMSGSIZE;
1615 }
1616
1617 const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
1618 [RTA_DST] = { .type = NLA_U16 },
1619 [RTA_SRC] = { .type = NLA_U16 },
1620 [RTA_IIF] = { .type = NLA_U32 },
1621 [RTA_OIF] = { .type = NLA_U32 },
1622 [RTA_GATEWAY] = { .type = NLA_U16 },
1623 [RTA_PRIORITY] = { .type = NLA_U32 },
1624 [RTA_PREFSRC] = { .type = NLA_U16 },
1625 [RTA_METRICS] = { .type = NLA_NESTED },
1626 [RTA_MULTIPATH] = { .type = NLA_NESTED },
1627 [RTA_TABLE] = { .type = NLA_U32 },
1628 [RTA_MARK] = { .type = NLA_U32 },
1629 };
1630
1631 /*
1632 * This is called by both endnodes and routers now.
1633 */
dn_cache_getroute(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)1634 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
1635 struct netlink_ext_ack *extack)
1636 {
1637 struct net *net = sock_net(in_skb->sk);
1638 struct rtmsg *rtm = nlmsg_data(nlh);
1639 struct dn_route *rt = NULL;
1640 struct dn_skb_cb *cb;
1641 int err;
1642 struct sk_buff *skb;
1643 struct flowidn fld;
1644 struct nlattr *tb[RTA_MAX+1];
1645
1646 if (!net_eq(net, &init_net))
1647 return -EINVAL;
1648
1649 err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
1650 rtm_dn_policy, extack);
1651 if (err < 0)
1652 return err;
1653
1654 memset(&fld, 0, sizeof(fld));
1655 fld.flowidn_proto = DNPROTO_NSP;
1656
1657 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1658 if (skb == NULL)
1659 return -ENOBUFS;
1660 skb_reset_mac_header(skb);
1661 cb = DN_SKB_CB(skb);
1662
1663 if (tb[RTA_SRC])
1664 fld.saddr = nla_get_le16(tb[RTA_SRC]);
1665
1666 if (tb[RTA_DST])
1667 fld.daddr = nla_get_le16(tb[RTA_DST]);
1668
1669 if (tb[RTA_IIF])
1670 fld.flowidn_iif = nla_get_u32(tb[RTA_IIF]);
1671
1672 if (fld.flowidn_iif) {
1673 struct net_device *dev;
1674 dev = __dev_get_by_index(&init_net, fld.flowidn_iif);
1675 if (!dev || !dev->dn_ptr) {
1676 kfree_skb(skb);
1677 return -ENODEV;
1678 }
1679 skb->protocol = htons(ETH_P_DNA_RT);
1680 skb->dev = dev;
1681 cb->src = fld.saddr;
1682 cb->dst = fld.daddr;
1683 local_bh_disable();
1684 err = dn_route_input(skb);
1685 local_bh_enable();
1686 memset(cb, 0, sizeof(struct dn_skb_cb));
1687 rt = (struct dn_route *)skb_dst(skb);
1688 if (!err && -rt->dst.error)
1689 err = rt->dst.error;
1690 } else {
1691 if (tb[RTA_OIF])
1692 fld.flowidn_oif = nla_get_u32(tb[RTA_OIF]);
1693
1694 err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
1695 }
1696
1697 skb->dev = NULL;
1698 if (err)
1699 goto out_free;
1700 skb_dst_set(skb, &rt->dst);
1701 if (rtm->rtm_flags & RTM_F_NOTIFY)
1702 rt->rt_flags |= RTCF_NOTIFY;
1703
1704 err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1705 if (err < 0) {
1706 err = -EMSGSIZE;
1707 goto out_free;
1708 }
1709
1710 return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).portid);
1711
1712 out_free:
1713 kfree_skb(skb);
1714 return err;
1715 }
1716
1717 /*
1718 * For routers, this is called from dn_fib_dump, but for endnodes its
1719 * called directly from the rtnetlink dispatch table.
1720 */
dn_cache_dump(struct sk_buff * skb,struct netlink_callback * cb)1721 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1722 {
1723 struct net *net = sock_net(skb->sk);
1724 struct dn_route *rt;
1725 int h, s_h;
1726 int idx, s_idx;
1727 struct rtmsg *rtm;
1728
1729 if (!net_eq(net, &init_net))
1730 return 0;
1731
1732 if (nlmsg_len(cb->nlh) < sizeof(struct rtmsg))
1733 return -EINVAL;
1734
1735 rtm = nlmsg_data(cb->nlh);
1736 if (!(rtm->rtm_flags & RTM_F_CLONED))
1737 return 0;
1738
1739 s_h = cb->args[0];
1740 s_idx = idx = cb->args[1];
1741 for (h = 0; h <= dn_rt_hash_mask; h++) {
1742 if (h < s_h)
1743 continue;
1744 if (h > s_h)
1745 s_idx = 0;
1746 rcu_read_lock_bh();
1747 for (rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
1748 rt;
1749 rt = rcu_dereference_bh(rt->dn_next), idx++) {
1750 if (idx < s_idx)
1751 continue;
1752 skb_dst_set(skb, dst_clone(&rt->dst));
1753 if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).portid,
1754 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1755 1, NLM_F_MULTI) < 0) {
1756 skb_dst_drop(skb);
1757 rcu_read_unlock_bh();
1758 goto done;
1759 }
1760 skb_dst_drop(skb);
1761 }
1762 rcu_read_unlock_bh();
1763 }
1764
1765 done:
1766 cb->args[0] = h;
1767 cb->args[1] = idx;
1768 return skb->len;
1769 }
1770
1771 #ifdef CONFIG_PROC_FS
1772 struct dn_rt_cache_iter_state {
1773 int bucket;
1774 };
1775
dn_rt_cache_get_first(struct seq_file * seq)1776 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1777 {
1778 struct dn_route *rt = NULL;
1779 struct dn_rt_cache_iter_state *s = seq->private;
1780
1781 for (s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1782 rcu_read_lock_bh();
1783 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1784 if (rt)
1785 break;
1786 rcu_read_unlock_bh();
1787 }
1788 return rt;
1789 }
1790
dn_rt_cache_get_next(struct seq_file * seq,struct dn_route * rt)1791 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1792 {
1793 struct dn_rt_cache_iter_state *s = seq->private;
1794
1795 rt = rcu_dereference_bh(rt->dn_next);
1796 while (!rt) {
1797 rcu_read_unlock_bh();
1798 if (--s->bucket < 0)
1799 break;
1800 rcu_read_lock_bh();
1801 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1802 }
1803 return rt;
1804 }
1805
dn_rt_cache_seq_start(struct seq_file * seq,loff_t * pos)1806 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1807 {
1808 struct dn_route *rt = dn_rt_cache_get_first(seq);
1809
1810 if (rt) {
1811 while (*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1812 --*pos;
1813 }
1814 return *pos ? NULL : rt;
1815 }
1816
dn_rt_cache_seq_next(struct seq_file * seq,void * v,loff_t * pos)1817 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1818 {
1819 struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1820 ++*pos;
1821 return rt;
1822 }
1823
dn_rt_cache_seq_stop(struct seq_file * seq,void * v)1824 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1825 {
1826 if (v)
1827 rcu_read_unlock_bh();
1828 }
1829
dn_rt_cache_seq_show(struct seq_file * seq,void * v)1830 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1831 {
1832 struct dn_route *rt = v;
1833 char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1834
1835 seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1836 rt->dst.dev ? rt->dst.dev->name : "*",
1837 dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
1838 dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
1839 atomic_read(&rt->dst.__refcnt),
1840 rt->dst.__use, 0);
1841 return 0;
1842 }
1843
1844 static const struct seq_operations dn_rt_cache_seq_ops = {
1845 .start = dn_rt_cache_seq_start,
1846 .next = dn_rt_cache_seq_next,
1847 .stop = dn_rt_cache_seq_stop,
1848 .show = dn_rt_cache_seq_show,
1849 };
1850 #endif /* CONFIG_PROC_FS */
1851
dn_route_init(void)1852 void __init dn_route_init(void)
1853 {
1854 int i, goal, order;
1855
1856 dn_dst_ops.kmem_cachep =
1857 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1858 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1859 dst_entries_init(&dn_dst_ops);
1860 timer_setup(&dn_route_timer, dn_dst_check_expire, 0);
1861 dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1862 add_timer(&dn_route_timer);
1863
1864 goal = totalram_pages() >> (26 - PAGE_SHIFT);
1865
1866 for (order = 0; (1UL << order) < goal; order++)
1867 /* NOTHING */;
1868
1869 /*
1870 * Only want 1024 entries max, since the table is very, very unlikely
1871 * to be larger than that.
1872 */
1873 while (order && ((((1UL << order) * PAGE_SIZE) /
1874 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1875 order--;
1876
1877 do {
1878 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1879 sizeof(struct dn_rt_hash_bucket);
1880 while (dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1881 dn_rt_hash_mask--;
1882 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1883 __get_free_pages(GFP_ATOMIC, order);
1884 } while (dn_rt_hash_table == NULL && --order > 0);
1885
1886 if (!dn_rt_hash_table)
1887 panic("Failed to allocate DECnet route cache hash table\n");
1888
1889 printk(KERN_INFO
1890 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1891 dn_rt_hash_mask,
1892 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1893
1894 dn_rt_hash_mask--;
1895 for (i = 0; i <= dn_rt_hash_mask; i++) {
1896 spin_lock_init(&dn_rt_hash_table[i].lock);
1897 dn_rt_hash_table[i].chain = NULL;
1898 }
1899
1900 dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1901
1902 proc_create_seq_private("decnet_cache", 0444, init_net.proc_net,
1903 &dn_rt_cache_seq_ops,
1904 sizeof(struct dn_rt_cache_iter_state), NULL);
1905
1906 #ifdef CONFIG_DECNET_ROUTER
1907 rtnl_register_module(THIS_MODULE, PF_DECnet, RTM_GETROUTE,
1908 dn_cache_getroute, dn_fib_dump, 0);
1909 #else
1910 rtnl_register_module(THIS_MODULE, PF_DECnet, RTM_GETROUTE,
1911 dn_cache_getroute, dn_cache_dump, 0);
1912 #endif
1913 }
1914
dn_route_cleanup(void)1915 void __exit dn_route_cleanup(void)
1916 {
1917 del_timer(&dn_route_timer);
1918 dn_run_flush(NULL);
1919
1920 remove_proc_entry("decnet_cache", init_net.proc_net);
1921 dst_entries_destroy(&dn_dst_ops);
1922 }
1923