1 /*
2 * DECnet An implementation of the DECnet protocol suite for the LINUX
3 * operating system. DECnet is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * DECnet Routing Functions (Endnode and Router)
7 *
8 * Authors: Steve Whitehouse <SteveW@ACM.org>
9 * Eduardo Marcelo Serrat <emserrat@geocities.com>
10 *
11 * Changes:
12 * Steve Whitehouse : Fixes to allow "intra-ethernet" and
13 * "return-to-sender" bits on outgoing
14 * packets.
15 * Steve Whitehouse : Timeouts for cached routes.
16 * Steve Whitehouse : Use dst cache for input routes too.
17 * Steve Whitehouse : Fixed error values in dn_send_skb.
18 * Steve Whitehouse : Rework routing functions to better fit
19 * DECnet routing design
20 * Alexey Kuznetsov : New SMP locking
21 * Steve Whitehouse : More SMP locking changes & dn_cache_dump()
22 * Steve Whitehouse : Prerouting NF hook, now really is prerouting.
23 * Fixed possible skb leak in rtnetlink funcs.
24 * Steve Whitehouse : Dave Miller's dynamic hash table sizing and
25 * Alexey Kuznetsov's finer grained locking
26 * from ipv4/route.c.
27 * Steve Whitehouse : Routing is now starting to look like a
28 * sensible set of code now, mainly due to
29 * my copying the IPv4 routing code. The
30 * hooks here are modified and will continue
31 * to evolve for a while.
32 * Steve Whitehouse : Real SMP at last :-) Also new netfilter
33 * stuff. Look out raw sockets your days
34 * are numbered!
35 * Steve Whitehouse : Added return-to-sender functions. Added
36 * backlog congestion level return codes.
37 * Steve Whitehouse : Fixed bug where routes were set up with
38 * no ref count on net devices.
39 * Steve Whitehouse : RCU for the route cache
40 * Steve Whitehouse : Preparations for the flow cache
41 * Steve Whitehouse : Prepare for nonlinear skbs
42 */
43
44 /******************************************************************************
45 (c) 1995-1998 E.M. Serrat emserrat@geocities.com
46
47 This program is free software; you can redistribute it and/or modify
48 it under the terms of the GNU General Public License as published by
49 the Free Software Foundation; either version 2 of the License, or
50 any later version.
51
52 This program is distributed in the hope that it will be useful,
53 but WITHOUT ANY WARRANTY; without even the implied warranty of
54 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
55 GNU General Public License for more details.
56 *******************************************************************************/
57
58 #include <linux/errno.h>
59 #include <linux/types.h>
60 #include <linux/socket.h>
61 #include <linux/in.h>
62 #include <linux/kernel.h>
63 #include <linux/sockios.h>
64 #include <linux/net.h>
65 #include <linux/netdevice.h>
66 #include <linux/inet.h>
67 #include <linux/route.h>
68 #include <linux/in_route.h>
69 #include <linux/slab.h>
70 #include <net/sock.h>
71 #include <linux/mm.h>
72 #include <linux/proc_fs.h>
73 #include <linux/seq_file.h>
74 #include <linux/init.h>
75 #include <linux/rtnetlink.h>
76 #include <linux/string.h>
77 #include <linux/netfilter_decnet.h>
78 #include <linux/rcupdate.h>
79 #include <linux/times.h>
80 #include <linux/export.h>
81 #include <asm/errno.h>
82 #include <net/net_namespace.h>
83 #include <net/netlink.h>
84 #include <net/neighbour.h>
85 #include <net/dst.h>
86 #include <net/flow.h>
87 #include <net/fib_rules.h>
88 #include <net/dn.h>
89 #include <net/dn_dev.h>
90 #include <net/dn_nsp.h>
91 #include <net/dn_route.h>
92 #include <net/dn_neigh.h>
93 #include <net/dn_fib.h>
94
95 struct dn_rt_hash_bucket
96 {
97 struct dn_route __rcu *chain;
98 spinlock_t lock;
99 };
100
101 extern struct neigh_table dn_neigh_table;
102
103
104 static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
105
106 static const int dn_rt_min_delay = 2 * HZ;
107 static const int dn_rt_max_delay = 10 * HZ;
108 static const int dn_rt_mtu_expires = 10 * 60 * HZ;
109
110 static unsigned long dn_rt_deadline;
111
112 static int dn_dst_gc(struct dst_ops *ops);
113 static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
114 static unsigned int dn_dst_default_advmss(const struct dst_entry *dst);
115 static unsigned int dn_dst_mtu(const struct dst_entry *dst);
116 static void dn_dst_destroy(struct dst_entry *);
117 static void dn_dst_ifdown(struct dst_entry *, struct net_device *dev, int how);
118 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
119 static void dn_dst_link_failure(struct sk_buff *);
120 static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
121 struct sk_buff *skb , u32 mtu);
122 static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
123 struct sk_buff *skb);
124 static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
125 struct sk_buff *skb,
126 const void *daddr);
127 static int dn_route_input(struct sk_buff *);
128 static void dn_run_flush(unsigned long dummy);
129
130 static struct dn_rt_hash_bucket *dn_rt_hash_table;
131 static unsigned int dn_rt_hash_mask;
132
133 static struct timer_list dn_route_timer;
134 static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
135 int decnet_dst_gc_interval = 2;
136
137 static struct dst_ops dn_dst_ops = {
138 .family = PF_DECnet,
139 .protocol = cpu_to_be16(ETH_P_DNA_RT),
140 .gc_thresh = 128,
141 .gc = dn_dst_gc,
142 .check = dn_dst_check,
143 .default_advmss = dn_dst_default_advmss,
144 .mtu = dn_dst_mtu,
145 .cow_metrics = dst_cow_metrics_generic,
146 .destroy = dn_dst_destroy,
147 .ifdown = dn_dst_ifdown,
148 .negative_advice = dn_dst_negative_advice,
149 .link_failure = dn_dst_link_failure,
150 .update_pmtu = dn_dst_update_pmtu,
151 .redirect = dn_dst_redirect,
152 .neigh_lookup = dn_dst_neigh_lookup,
153 };
154
dn_dst_destroy(struct dst_entry * dst)155 static void dn_dst_destroy(struct dst_entry *dst)
156 {
157 struct dn_route *rt = (struct dn_route *) dst;
158
159 if (rt->n)
160 neigh_release(rt->n);
161 dst_destroy_metrics_generic(dst);
162 }
163
dn_dst_ifdown(struct dst_entry * dst,struct net_device * dev,int how)164 static void dn_dst_ifdown(struct dst_entry *dst, struct net_device *dev, int how)
165 {
166 if (how) {
167 struct dn_route *rt = (struct dn_route *) dst;
168 struct neighbour *n = rt->n;
169
170 if (n && n->dev == dev) {
171 n->dev = dev_net(dev)->loopback_dev;
172 dev_hold(n->dev);
173 dev_put(dev);
174 }
175 }
176 }
177
dn_hash(__le16 src,__le16 dst)178 static __inline__ unsigned int dn_hash(__le16 src, __le16 dst)
179 {
180 __u16 tmp = (__u16 __force)(src ^ dst);
181 tmp ^= (tmp >> 3);
182 tmp ^= (tmp >> 5);
183 tmp ^= (tmp >> 10);
184 return dn_rt_hash_mask & (unsigned int)tmp;
185 }
186
dnrt_free(struct dn_route * rt)187 static inline void dnrt_free(struct dn_route *rt)
188 {
189 call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
190 }
191
dn_dst_check_expire(unsigned long dummy)192 static void dn_dst_check_expire(unsigned long dummy)
193 {
194 int i;
195 struct dn_route *rt;
196 struct dn_route __rcu **rtp;
197 unsigned long now = jiffies;
198 unsigned long expire = 120 * HZ;
199
200 for (i = 0; i <= dn_rt_hash_mask; i++) {
201 rtp = &dn_rt_hash_table[i].chain;
202
203 spin_lock(&dn_rt_hash_table[i].lock);
204 while ((rt = rcu_dereference_protected(*rtp,
205 lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
206 if (atomic_read(&rt->dst.__refcnt) ||
207 (now - rt->dst.lastuse) < expire) {
208 rtp = &rt->dst.dn_next;
209 continue;
210 }
211 *rtp = rt->dst.dn_next;
212 rt->dst.dn_next = NULL;
213 dnrt_free(rt);
214 }
215 spin_unlock(&dn_rt_hash_table[i].lock);
216
217 if ((jiffies - now) > 0)
218 break;
219 }
220
221 mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ);
222 }
223
dn_dst_gc(struct dst_ops * ops)224 static int dn_dst_gc(struct dst_ops *ops)
225 {
226 struct dn_route *rt;
227 struct dn_route __rcu **rtp;
228 int i;
229 unsigned long now = jiffies;
230 unsigned long expire = 10 * HZ;
231
232 for (i = 0; i <= dn_rt_hash_mask; i++) {
233
234 spin_lock_bh(&dn_rt_hash_table[i].lock);
235 rtp = &dn_rt_hash_table[i].chain;
236
237 while ((rt = rcu_dereference_protected(*rtp,
238 lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
239 if (atomic_read(&rt->dst.__refcnt) ||
240 (now - rt->dst.lastuse) < expire) {
241 rtp = &rt->dst.dn_next;
242 continue;
243 }
244 *rtp = rt->dst.dn_next;
245 rt->dst.dn_next = NULL;
246 dnrt_free(rt);
247 break;
248 }
249 spin_unlock_bh(&dn_rt_hash_table[i].lock);
250 }
251
252 return 0;
253 }
254
255 /*
256 * The decnet standards don't impose a particular minimum mtu, what they
257 * do insist on is that the routing layer accepts a datagram of at least
258 * 230 bytes long. Here we have to subtract the routing header length from
259 * 230 to get the minimum acceptable mtu. If there is no neighbour, then we
260 * assume the worst and use a long header size.
261 *
262 * We update both the mtu and the advertised mss (i.e. the segment size we
263 * advertise to the other end).
264 */
dn_dst_update_pmtu(struct dst_entry * dst,struct sock * sk,struct sk_buff * skb,u32 mtu)265 static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
266 struct sk_buff *skb, u32 mtu)
267 {
268 struct dn_route *rt = (struct dn_route *) dst;
269 struct neighbour *n = rt->n;
270 u32 min_mtu = 230;
271 struct dn_dev *dn;
272
273 dn = n ? rcu_dereference_raw(n->dev->dn_ptr) : NULL;
274
275 if (dn && dn->use_long == 0)
276 min_mtu -= 6;
277 else
278 min_mtu -= 21;
279
280 if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= min_mtu) {
281 if (!(dst_metric_locked(dst, RTAX_MTU))) {
282 dst_metric_set(dst, RTAX_MTU, mtu);
283 dst_set_expires(dst, dn_rt_mtu_expires);
284 }
285 if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
286 u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
287 u32 existing_mss = dst_metric_raw(dst, RTAX_ADVMSS);
288 if (!existing_mss || existing_mss > mss)
289 dst_metric_set(dst, RTAX_ADVMSS, mss);
290 }
291 }
292 }
293
dn_dst_redirect(struct dst_entry * dst,struct sock * sk,struct sk_buff * skb)294 static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
295 struct sk_buff *skb)
296 {
297 }
298
299 /*
300 * When a route has been marked obsolete. (e.g. routing cache flush)
301 */
dn_dst_check(struct dst_entry * dst,__u32 cookie)302 static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
303 {
304 return NULL;
305 }
306
dn_dst_negative_advice(struct dst_entry * dst)307 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
308 {
309 dst_release(dst);
310 return NULL;
311 }
312
dn_dst_link_failure(struct sk_buff * skb)313 static void dn_dst_link_failure(struct sk_buff *skb)
314 {
315 }
316
compare_keys(struct flowidn * fl1,struct flowidn * fl2)317 static inline int compare_keys(struct flowidn *fl1, struct flowidn *fl2)
318 {
319 return ((fl1->daddr ^ fl2->daddr) |
320 (fl1->saddr ^ fl2->saddr) |
321 (fl1->flowidn_mark ^ fl2->flowidn_mark) |
322 (fl1->flowidn_scope ^ fl2->flowidn_scope) |
323 (fl1->flowidn_oif ^ fl2->flowidn_oif) |
324 (fl1->flowidn_iif ^ fl2->flowidn_iif)) == 0;
325 }
326
dn_insert_route(struct dn_route * rt,unsigned int hash,struct dn_route ** rp)327 static int dn_insert_route(struct dn_route *rt, unsigned int hash, struct dn_route **rp)
328 {
329 struct dn_route *rth;
330 struct dn_route __rcu **rthp;
331 unsigned long now = jiffies;
332
333 rthp = &dn_rt_hash_table[hash].chain;
334
335 spin_lock_bh(&dn_rt_hash_table[hash].lock);
336 while ((rth = rcu_dereference_protected(*rthp,
337 lockdep_is_held(&dn_rt_hash_table[hash].lock))) != NULL) {
338 if (compare_keys(&rth->fld, &rt->fld)) {
339 /* Put it first */
340 *rthp = rth->dst.dn_next;
341 rcu_assign_pointer(rth->dst.dn_next,
342 dn_rt_hash_table[hash].chain);
343 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
344
345 dst_use(&rth->dst, now);
346 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
347
348 dst_free(&rt->dst);
349 *rp = rth;
350 return 0;
351 }
352 rthp = &rth->dst.dn_next;
353 }
354
355 rcu_assign_pointer(rt->dst.dn_next, dn_rt_hash_table[hash].chain);
356 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
357
358 dst_use(&rt->dst, now);
359 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
360 *rp = rt;
361 return 0;
362 }
363
dn_run_flush(unsigned long dummy)364 static void dn_run_flush(unsigned long dummy)
365 {
366 int i;
367 struct dn_route *rt, *next;
368
369 for (i = 0; i < dn_rt_hash_mask; i++) {
370 spin_lock_bh(&dn_rt_hash_table[i].lock);
371
372 if ((rt = xchg((struct dn_route **)&dn_rt_hash_table[i].chain, NULL)) == NULL)
373 goto nothing_to_declare;
374
375 for(; rt; rt = next) {
376 next = rcu_dereference_raw(rt->dst.dn_next);
377 RCU_INIT_POINTER(rt->dst.dn_next, NULL);
378 dnrt_free(rt);
379 }
380
381 nothing_to_declare:
382 spin_unlock_bh(&dn_rt_hash_table[i].lock);
383 }
384 }
385
386 static DEFINE_SPINLOCK(dn_rt_flush_lock);
387
dn_rt_cache_flush(int delay)388 void dn_rt_cache_flush(int delay)
389 {
390 unsigned long now = jiffies;
391 int user_mode = !in_interrupt();
392
393 if (delay < 0)
394 delay = dn_rt_min_delay;
395
396 spin_lock_bh(&dn_rt_flush_lock);
397
398 if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
399 long tmo = (long)(dn_rt_deadline - now);
400
401 if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
402 tmo = 0;
403
404 if (delay > tmo)
405 delay = tmo;
406 }
407
408 if (delay <= 0) {
409 spin_unlock_bh(&dn_rt_flush_lock);
410 dn_run_flush(0);
411 return;
412 }
413
414 if (dn_rt_deadline == 0)
415 dn_rt_deadline = now + dn_rt_max_delay;
416
417 dn_rt_flush_timer.expires = now + delay;
418 add_timer(&dn_rt_flush_timer);
419 spin_unlock_bh(&dn_rt_flush_lock);
420 }
421
422 /**
423 * dn_return_short - Return a short packet to its sender
424 * @skb: The packet to return
425 *
426 */
dn_return_short(struct sk_buff * skb)427 static int dn_return_short(struct sk_buff *skb)
428 {
429 struct dn_skb_cb *cb;
430 unsigned char *ptr;
431 __le16 *src;
432 __le16 *dst;
433
434 /* Add back headers */
435 skb_push(skb, skb->data - skb_network_header(skb));
436
437 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
438 return NET_RX_DROP;
439
440 cb = DN_SKB_CB(skb);
441 /* Skip packet length and point to flags */
442 ptr = skb->data + 2;
443 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
444
445 dst = (__le16 *)ptr;
446 ptr += 2;
447 src = (__le16 *)ptr;
448 ptr += 2;
449 *ptr = 0; /* Zero hop count */
450
451 swap(*src, *dst);
452
453 skb->pkt_type = PACKET_OUTGOING;
454 dn_rt_finish_output(skb, NULL, NULL);
455 return NET_RX_SUCCESS;
456 }
457
458 /**
459 * dn_return_long - Return a long packet to its sender
460 * @skb: The long format packet to return
461 *
462 */
dn_return_long(struct sk_buff * skb)463 static int dn_return_long(struct sk_buff *skb)
464 {
465 struct dn_skb_cb *cb;
466 unsigned char *ptr;
467 unsigned char *src_addr, *dst_addr;
468 unsigned char tmp[ETH_ALEN];
469
470 /* Add back all headers */
471 skb_push(skb, skb->data - skb_network_header(skb));
472
473 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
474 return NET_RX_DROP;
475
476 cb = DN_SKB_CB(skb);
477 /* Ignore packet length and point to flags */
478 ptr = skb->data + 2;
479
480 /* Skip padding */
481 if (*ptr & DN_RT_F_PF) {
482 char padlen = (*ptr & ~DN_RT_F_PF);
483 ptr += padlen;
484 }
485
486 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
487 ptr += 2;
488 dst_addr = ptr;
489 ptr += 8;
490 src_addr = ptr;
491 ptr += 6;
492 *ptr = 0; /* Zero hop count */
493
494 /* Swap source and destination */
495 memcpy(tmp, src_addr, ETH_ALEN);
496 memcpy(src_addr, dst_addr, ETH_ALEN);
497 memcpy(dst_addr, tmp, ETH_ALEN);
498
499 skb->pkt_type = PACKET_OUTGOING;
500 dn_rt_finish_output(skb, dst_addr, src_addr);
501 return NET_RX_SUCCESS;
502 }
503
504 /**
505 * dn_route_rx_packet - Try and find a route for an incoming packet
506 * @skb: The packet to find a route for
507 *
508 * Returns: result of input function if route is found, error code otherwise
509 */
dn_route_rx_packet(struct sk_buff * skb)510 static int dn_route_rx_packet(struct sk_buff *skb)
511 {
512 struct dn_skb_cb *cb;
513 int err;
514
515 if ((err = dn_route_input(skb)) == 0)
516 return dst_input(skb);
517
518 cb = DN_SKB_CB(skb);
519 if (decnet_debug_level & 4) {
520 char *devname = skb->dev ? skb->dev->name : "???";
521
522 printk(KERN_DEBUG
523 "DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
524 (int)cb->rt_flags, devname, skb->len,
525 le16_to_cpu(cb->src), le16_to_cpu(cb->dst),
526 err, skb->pkt_type);
527 }
528
529 if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
530 switch (cb->rt_flags & DN_RT_PKT_MSK) {
531 case DN_RT_PKT_SHORT:
532 return dn_return_short(skb);
533 case DN_RT_PKT_LONG:
534 return dn_return_long(skb);
535 }
536 }
537
538 kfree_skb(skb);
539 return NET_RX_DROP;
540 }
541
dn_route_rx_long(struct sk_buff * skb)542 static int dn_route_rx_long(struct sk_buff *skb)
543 {
544 struct dn_skb_cb *cb = DN_SKB_CB(skb);
545 unsigned char *ptr = skb->data;
546
547 if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
548 goto drop_it;
549
550 skb_pull(skb, 20);
551 skb_reset_transport_header(skb);
552
553 /* Destination info */
554 ptr += 2;
555 cb->dst = dn_eth2dn(ptr);
556 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
557 goto drop_it;
558 ptr += 6;
559
560
561 /* Source info */
562 ptr += 2;
563 cb->src = dn_eth2dn(ptr);
564 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
565 goto drop_it;
566 ptr += 6;
567 /* Other junk */
568 ptr++;
569 cb->hops = *ptr++; /* Visit Count */
570
571 return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, skb, skb->dev, NULL,
572 dn_route_rx_packet);
573
574 drop_it:
575 kfree_skb(skb);
576 return NET_RX_DROP;
577 }
578
579
580
dn_route_rx_short(struct sk_buff * skb)581 static int dn_route_rx_short(struct sk_buff *skb)
582 {
583 struct dn_skb_cb *cb = DN_SKB_CB(skb);
584 unsigned char *ptr = skb->data;
585
586 if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
587 goto drop_it;
588
589 skb_pull(skb, 5);
590 skb_reset_transport_header(skb);
591
592 cb->dst = *(__le16 *)ptr;
593 ptr += 2;
594 cb->src = *(__le16 *)ptr;
595 ptr += 2;
596 cb->hops = *ptr & 0x3f;
597
598 return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, skb, skb->dev, NULL,
599 dn_route_rx_packet);
600
601 drop_it:
602 kfree_skb(skb);
603 return NET_RX_DROP;
604 }
605
dn_route_discard(struct sk_buff * skb)606 static int dn_route_discard(struct sk_buff *skb)
607 {
608 /*
609 * I know we drop the packet here, but thats considered success in
610 * this case
611 */
612 kfree_skb(skb);
613 return NET_RX_SUCCESS;
614 }
615
dn_route_ptp_hello(struct sk_buff * skb)616 static int dn_route_ptp_hello(struct sk_buff *skb)
617 {
618 dn_dev_hello(skb);
619 dn_neigh_pointopoint_hello(skb);
620 return NET_RX_SUCCESS;
621 }
622
dn_route_rcv(struct sk_buff * skb,struct net_device * dev,struct packet_type * pt,struct net_device * orig_dev)623 int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
624 {
625 struct dn_skb_cb *cb;
626 unsigned char flags = 0;
627 __u16 len = le16_to_cpu(*(__le16 *)skb->data);
628 struct dn_dev *dn = rcu_dereference(dev->dn_ptr);
629 unsigned char padlen = 0;
630
631 if (!net_eq(dev_net(dev), &init_net))
632 goto dump_it;
633
634 if (dn == NULL)
635 goto dump_it;
636
637 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
638 goto out;
639
640 if (!pskb_may_pull(skb, 3))
641 goto dump_it;
642
643 skb_pull(skb, 2);
644
645 if (len > skb->len)
646 goto dump_it;
647
648 skb_trim(skb, len);
649
650 flags = *skb->data;
651
652 cb = DN_SKB_CB(skb);
653 cb->stamp = jiffies;
654 cb->iif = dev->ifindex;
655
656 /*
657 * If we have padding, remove it.
658 */
659 if (flags & DN_RT_F_PF) {
660 padlen = flags & ~DN_RT_F_PF;
661 if (!pskb_may_pull(skb, padlen + 1))
662 goto dump_it;
663 skb_pull(skb, padlen);
664 flags = *skb->data;
665 }
666
667 skb_reset_network_header(skb);
668
669 /*
670 * Weed out future version DECnet
671 */
672 if (flags & DN_RT_F_VER)
673 goto dump_it;
674
675 cb->rt_flags = flags;
676
677 if (decnet_debug_level & 1)
678 printk(KERN_DEBUG
679 "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
680 (int)flags, (dev) ? dev->name : "???", len, skb->len,
681 padlen);
682
683 if (flags & DN_RT_PKT_CNTL) {
684 if (unlikely(skb_linearize(skb)))
685 goto dump_it;
686
687 switch (flags & DN_RT_CNTL_MSK) {
688 case DN_RT_PKT_INIT:
689 dn_dev_init_pkt(skb);
690 break;
691 case DN_RT_PKT_VERI:
692 dn_dev_veri_pkt(skb);
693 break;
694 }
695
696 if (dn->parms.state != DN_DEV_S_RU)
697 goto dump_it;
698
699 switch (flags & DN_RT_CNTL_MSK) {
700 case DN_RT_PKT_HELO:
701 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
702 skb, skb->dev, NULL,
703 dn_route_ptp_hello);
704
705 case DN_RT_PKT_L1RT:
706 case DN_RT_PKT_L2RT:
707 return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE,
708 skb, skb->dev, NULL,
709 dn_route_discard);
710 case DN_RT_PKT_ERTH:
711 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
712 skb, skb->dev, NULL,
713 dn_neigh_router_hello);
714
715 case DN_RT_PKT_EEDH:
716 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
717 skb, skb->dev, NULL,
718 dn_neigh_endnode_hello);
719 }
720 } else {
721 if (dn->parms.state != DN_DEV_S_RU)
722 goto dump_it;
723
724 skb_pull(skb, 1); /* Pull flags */
725
726 switch (flags & DN_RT_PKT_MSK) {
727 case DN_RT_PKT_LONG:
728 return dn_route_rx_long(skb);
729 case DN_RT_PKT_SHORT:
730 return dn_route_rx_short(skb);
731 }
732 }
733
734 dump_it:
735 kfree_skb(skb);
736 out:
737 return NET_RX_DROP;
738 }
739
dn_to_neigh_output(struct sk_buff * skb)740 static int dn_to_neigh_output(struct sk_buff *skb)
741 {
742 struct dst_entry *dst = skb_dst(skb);
743 struct dn_route *rt = (struct dn_route *) dst;
744 struct neighbour *n = rt->n;
745
746 return n->output(n, skb);
747 }
748
dn_output(struct sock * sk,struct sk_buff * skb)749 static int dn_output(struct sock *sk, struct sk_buff *skb)
750 {
751 struct dst_entry *dst = skb_dst(skb);
752 struct dn_route *rt = (struct dn_route *)dst;
753 struct net_device *dev = dst->dev;
754 struct dn_skb_cb *cb = DN_SKB_CB(skb);
755
756 int err = -EINVAL;
757
758 if (rt->n == NULL)
759 goto error;
760
761 skb->dev = dev;
762
763 cb->src = rt->rt_saddr;
764 cb->dst = rt->rt_daddr;
765
766 /*
767 * Always set the Intra-Ethernet bit on all outgoing packets
768 * originated on this node. Only valid flag from upper layers
769 * is return-to-sender-requested. Set hop count to 0 too.
770 */
771 cb->rt_flags &= ~DN_RT_F_RQR;
772 cb->rt_flags |= DN_RT_F_IE;
773 cb->hops = 0;
774
775 return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT, skb, NULL, dev,
776 dn_to_neigh_output);
777
778 error:
779 net_dbg_ratelimited("dn_output: This should not happen\n");
780
781 kfree_skb(skb);
782
783 return err;
784 }
785
dn_forward(struct sk_buff * skb)786 static int dn_forward(struct sk_buff *skb)
787 {
788 struct dn_skb_cb *cb = DN_SKB_CB(skb);
789 struct dst_entry *dst = skb_dst(skb);
790 struct dn_dev *dn_db = rcu_dereference(dst->dev->dn_ptr);
791 struct dn_route *rt;
792 int header_len;
793 #ifdef CONFIG_NETFILTER
794 struct net_device *dev = skb->dev;
795 #endif
796
797 if (skb->pkt_type != PACKET_HOST)
798 goto drop;
799
800 /* Ensure that we have enough space for headers */
801 rt = (struct dn_route *)skb_dst(skb);
802 header_len = dn_db->use_long ? 21 : 6;
803 if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+header_len))
804 goto drop;
805
806 /*
807 * Hop count exceeded.
808 */
809 if (++cb->hops > 30)
810 goto drop;
811
812 skb->dev = rt->dst.dev;
813
814 /*
815 * If packet goes out same interface it came in on, then set
816 * the Intra-Ethernet bit. This has no effect for short
817 * packets, so we don't need to test for them here.
818 */
819 cb->rt_flags &= ~DN_RT_F_IE;
820 if (rt->rt_flags & RTCF_DOREDIRECT)
821 cb->rt_flags |= DN_RT_F_IE;
822
823 return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD, skb, dev, skb->dev,
824 dn_to_neigh_output);
825
826 drop:
827 kfree_skb(skb);
828 return NET_RX_DROP;
829 }
830
831 /*
832 * Used to catch bugs. This should never normally get
833 * called.
834 */
dn_rt_bug_sk(struct sock * sk,struct sk_buff * skb)835 static int dn_rt_bug_sk(struct sock *sk, struct sk_buff *skb)
836 {
837 struct dn_skb_cb *cb = DN_SKB_CB(skb);
838
839 net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
840 le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
841
842 kfree_skb(skb);
843
844 return NET_RX_DROP;
845 }
846
dn_rt_bug(struct sk_buff * skb)847 static int dn_rt_bug(struct sk_buff *skb)
848 {
849 struct dn_skb_cb *cb = DN_SKB_CB(skb);
850
851 net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
852 le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
853
854 kfree_skb(skb);
855
856 return NET_RX_DROP;
857 }
858
dn_dst_default_advmss(const struct dst_entry * dst)859 static unsigned int dn_dst_default_advmss(const struct dst_entry *dst)
860 {
861 return dn_mss_from_pmtu(dst->dev, dst_mtu(dst));
862 }
863
dn_dst_mtu(const struct dst_entry * dst)864 static unsigned int dn_dst_mtu(const struct dst_entry *dst)
865 {
866 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
867
868 return mtu ? : dst->dev->mtu;
869 }
870
dn_dst_neigh_lookup(const struct dst_entry * dst,struct sk_buff * skb,const void * daddr)871 static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
872 struct sk_buff *skb,
873 const void *daddr)
874 {
875 return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
876 }
877
dn_rt_set_next_hop(struct dn_route * rt,struct dn_fib_res * res)878 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
879 {
880 struct dn_fib_info *fi = res->fi;
881 struct net_device *dev = rt->dst.dev;
882 unsigned int mss_metric;
883 struct neighbour *n;
884
885 if (fi) {
886 if (DN_FIB_RES_GW(*res) &&
887 DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
888 rt->rt_gateway = DN_FIB_RES_GW(*res);
889 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
890 }
891 rt->rt_type = res->type;
892
893 if (dev != NULL && rt->n == NULL) {
894 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
895 if (IS_ERR(n))
896 return PTR_ERR(n);
897 rt->n = n;
898 }
899
900 if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
901 dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
902 mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
903 if (mss_metric) {
904 unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
905 if (mss_metric > mss)
906 dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
907 }
908 return 0;
909 }
910
dn_match_addr(__le16 addr1,__le16 addr2)911 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
912 {
913 __u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
914 int match = 16;
915 while(tmp) {
916 tmp >>= 1;
917 match--;
918 }
919 return match;
920 }
921
dnet_select_source(const struct net_device * dev,__le16 daddr,int scope)922 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
923 {
924 __le16 saddr = 0;
925 struct dn_dev *dn_db;
926 struct dn_ifaddr *ifa;
927 int best_match = 0;
928 int ret;
929
930 rcu_read_lock();
931 dn_db = rcu_dereference(dev->dn_ptr);
932 for (ifa = rcu_dereference(dn_db->ifa_list);
933 ifa != NULL;
934 ifa = rcu_dereference(ifa->ifa_next)) {
935 if (ifa->ifa_scope > scope)
936 continue;
937 if (!daddr) {
938 saddr = ifa->ifa_local;
939 break;
940 }
941 ret = dn_match_addr(daddr, ifa->ifa_local);
942 if (ret > best_match)
943 saddr = ifa->ifa_local;
944 if (best_match == 0)
945 saddr = ifa->ifa_local;
946 }
947 rcu_read_unlock();
948
949 return saddr;
950 }
951
__dn_fib_res_prefsrc(struct dn_fib_res * res)952 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
953 {
954 return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
955 }
956
dn_fib_rules_map_destination(__le16 daddr,struct dn_fib_res * res)957 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
958 {
959 __le16 mask = dnet_make_mask(res->prefixlen);
960 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
961 }
962
dn_route_output_slow(struct dst_entry ** pprt,const struct flowidn * oldflp,int try_hard)963 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard)
964 {
965 struct flowidn fld = {
966 .daddr = oldflp->daddr,
967 .saddr = oldflp->saddr,
968 .flowidn_scope = RT_SCOPE_UNIVERSE,
969 .flowidn_mark = oldflp->flowidn_mark,
970 .flowidn_iif = LOOPBACK_IFINDEX,
971 .flowidn_oif = oldflp->flowidn_oif,
972 };
973 struct dn_route *rt = NULL;
974 struct net_device *dev_out = NULL, *dev;
975 struct neighbour *neigh = NULL;
976 unsigned int hash;
977 unsigned int flags = 0;
978 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
979 int err;
980 int free_res = 0;
981 __le16 gateway = 0;
982
983 if (decnet_debug_level & 16)
984 printk(KERN_DEBUG
985 "dn_route_output_slow: dst=%04x src=%04x mark=%d"
986 " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
987 le16_to_cpu(oldflp->saddr),
988 oldflp->flowidn_mark, LOOPBACK_IFINDEX,
989 oldflp->flowidn_oif);
990
991 /* If we have an output interface, verify its a DECnet device */
992 if (oldflp->flowidn_oif) {
993 dev_out = dev_get_by_index(&init_net, oldflp->flowidn_oif);
994 err = -ENODEV;
995 if (dev_out && dev_out->dn_ptr == NULL) {
996 dev_put(dev_out);
997 dev_out = NULL;
998 }
999 if (dev_out == NULL)
1000 goto out;
1001 }
1002
1003 /* If we have a source address, verify that its a local address */
1004 if (oldflp->saddr) {
1005 err = -EADDRNOTAVAIL;
1006
1007 if (dev_out) {
1008 if (dn_dev_islocal(dev_out, oldflp->saddr))
1009 goto source_ok;
1010 dev_put(dev_out);
1011 goto out;
1012 }
1013 rcu_read_lock();
1014 for_each_netdev_rcu(&init_net, dev) {
1015 if (!dev->dn_ptr)
1016 continue;
1017 if (!dn_dev_islocal(dev, oldflp->saddr))
1018 continue;
1019 if ((dev->flags & IFF_LOOPBACK) &&
1020 oldflp->daddr &&
1021 !dn_dev_islocal(dev, oldflp->daddr))
1022 continue;
1023
1024 dev_out = dev;
1025 break;
1026 }
1027 rcu_read_unlock();
1028 if (dev_out == NULL)
1029 goto out;
1030 dev_hold(dev_out);
1031 source_ok:
1032 ;
1033 }
1034
1035 /* No destination? Assume its local */
1036 if (!fld.daddr) {
1037 fld.daddr = fld.saddr;
1038
1039 if (dev_out)
1040 dev_put(dev_out);
1041 err = -EINVAL;
1042 dev_out = init_net.loopback_dev;
1043 if (!dev_out->dn_ptr)
1044 goto out;
1045 err = -EADDRNOTAVAIL;
1046 dev_hold(dev_out);
1047 if (!fld.daddr) {
1048 fld.daddr =
1049 fld.saddr = dnet_select_source(dev_out, 0,
1050 RT_SCOPE_HOST);
1051 if (!fld.daddr)
1052 goto out;
1053 }
1054 fld.flowidn_oif = LOOPBACK_IFINDEX;
1055 res.type = RTN_LOCAL;
1056 goto make_route;
1057 }
1058
1059 if (decnet_debug_level & 16)
1060 printk(KERN_DEBUG
1061 "dn_route_output_slow: initial checks complete."
1062 " dst=%o4x src=%04x oif=%d try_hard=%d\n",
1063 le16_to_cpu(fld.daddr), le16_to_cpu(fld.saddr),
1064 fld.flowidn_oif, try_hard);
1065
1066 /*
1067 * N.B. If the kernel is compiled without router support then
1068 * dn_fib_lookup() will evaluate to non-zero so this if () block
1069 * will always be executed.
1070 */
1071 err = -ESRCH;
1072 if (try_hard || (err = dn_fib_lookup(&fld, &res)) != 0) {
1073 struct dn_dev *dn_db;
1074 if (err != -ESRCH)
1075 goto out;
1076 /*
1077 * Here the fallback is basically the standard algorithm for
1078 * routing in endnodes which is described in the DECnet routing
1079 * docs
1080 *
1081 * If we are not trying hard, look in neighbour cache.
1082 * The result is tested to ensure that if a specific output
1083 * device/source address was requested, then we honour that
1084 * here
1085 */
1086 if (!try_hard) {
1087 neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fld.daddr);
1088 if (neigh) {
1089 if ((oldflp->flowidn_oif &&
1090 (neigh->dev->ifindex != oldflp->flowidn_oif)) ||
1091 (oldflp->saddr &&
1092 (!dn_dev_islocal(neigh->dev,
1093 oldflp->saddr)))) {
1094 neigh_release(neigh);
1095 neigh = NULL;
1096 } else {
1097 if (dev_out)
1098 dev_put(dev_out);
1099 if (dn_dev_islocal(neigh->dev, fld.daddr)) {
1100 dev_out = init_net.loopback_dev;
1101 res.type = RTN_LOCAL;
1102 } else {
1103 dev_out = neigh->dev;
1104 }
1105 dev_hold(dev_out);
1106 goto select_source;
1107 }
1108 }
1109 }
1110
1111 /* Not there? Perhaps its a local address */
1112 if (dev_out == NULL)
1113 dev_out = dn_dev_get_default();
1114 err = -ENODEV;
1115 if (dev_out == NULL)
1116 goto out;
1117 dn_db = rcu_dereference_raw(dev_out->dn_ptr);
1118 if (!dn_db)
1119 goto e_inval;
1120 /* Possible improvement - check all devices for local addr */
1121 if (dn_dev_islocal(dev_out, fld.daddr)) {
1122 dev_put(dev_out);
1123 dev_out = init_net.loopback_dev;
1124 dev_hold(dev_out);
1125 res.type = RTN_LOCAL;
1126 goto select_source;
1127 }
1128 /* Not local either.... try sending it to the default router */
1129 neigh = neigh_clone(dn_db->router);
1130 BUG_ON(neigh && neigh->dev != dev_out);
1131
1132 /* Ok then, we assume its directly connected and move on */
1133 select_source:
1134 if (neigh)
1135 gateway = ((struct dn_neigh *)neigh)->addr;
1136 if (gateway == 0)
1137 gateway = fld.daddr;
1138 if (fld.saddr == 0) {
1139 fld.saddr = dnet_select_source(dev_out, gateway,
1140 res.type == RTN_LOCAL ?
1141 RT_SCOPE_HOST :
1142 RT_SCOPE_LINK);
1143 if (fld.saddr == 0 && res.type != RTN_LOCAL)
1144 goto e_addr;
1145 }
1146 fld.flowidn_oif = dev_out->ifindex;
1147 goto make_route;
1148 }
1149 free_res = 1;
1150
1151 if (res.type == RTN_NAT)
1152 goto e_inval;
1153
1154 if (res.type == RTN_LOCAL) {
1155 if (!fld.saddr)
1156 fld.saddr = fld.daddr;
1157 if (dev_out)
1158 dev_put(dev_out);
1159 dev_out = init_net.loopback_dev;
1160 dev_hold(dev_out);
1161 if (!dev_out->dn_ptr)
1162 goto e_inval;
1163 fld.flowidn_oif = dev_out->ifindex;
1164 if (res.fi)
1165 dn_fib_info_put(res.fi);
1166 res.fi = NULL;
1167 goto make_route;
1168 }
1169
1170 if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1171 dn_fib_select_multipath(&fld, &res);
1172
1173 /*
1174 * We could add some logic to deal with default routes here and
1175 * get rid of some of the special casing above.
1176 */
1177
1178 if (!fld.saddr)
1179 fld.saddr = DN_FIB_RES_PREFSRC(res);
1180
1181 if (dev_out)
1182 dev_put(dev_out);
1183 dev_out = DN_FIB_RES_DEV(res);
1184 dev_hold(dev_out);
1185 fld.flowidn_oif = dev_out->ifindex;
1186 gateway = DN_FIB_RES_GW(res);
1187
1188 make_route:
1189 if (dev_out->flags & IFF_LOOPBACK)
1190 flags |= RTCF_LOCAL;
1191
1192 rt = dst_alloc(&dn_dst_ops, dev_out, 0, DST_OBSOLETE_NONE, DST_HOST);
1193 if (rt == NULL)
1194 goto e_nobufs;
1195
1196 memset(&rt->fld, 0, sizeof(rt->fld));
1197 rt->fld.saddr = oldflp->saddr;
1198 rt->fld.daddr = oldflp->daddr;
1199 rt->fld.flowidn_oif = oldflp->flowidn_oif;
1200 rt->fld.flowidn_iif = 0;
1201 rt->fld.flowidn_mark = oldflp->flowidn_mark;
1202
1203 rt->rt_saddr = fld.saddr;
1204 rt->rt_daddr = fld.daddr;
1205 rt->rt_gateway = gateway ? gateway : fld.daddr;
1206 rt->rt_local_src = fld.saddr;
1207
1208 rt->rt_dst_map = fld.daddr;
1209 rt->rt_src_map = fld.saddr;
1210
1211 rt->n = neigh;
1212 neigh = NULL;
1213
1214 rt->dst.lastuse = jiffies;
1215 rt->dst.output = dn_output;
1216 rt->dst.input = dn_rt_bug;
1217 rt->rt_flags = flags;
1218 if (flags & RTCF_LOCAL)
1219 rt->dst.input = dn_nsp_rx;
1220
1221 err = dn_rt_set_next_hop(rt, &res);
1222 if (err)
1223 goto e_neighbour;
1224
1225 hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1226 dn_insert_route(rt, hash, (struct dn_route **)pprt);
1227
1228 done:
1229 if (neigh)
1230 neigh_release(neigh);
1231 if (free_res)
1232 dn_fib_res_put(&res);
1233 if (dev_out)
1234 dev_put(dev_out);
1235 out:
1236 return err;
1237
1238 e_addr:
1239 err = -EADDRNOTAVAIL;
1240 goto done;
1241 e_inval:
1242 err = -EINVAL;
1243 goto done;
1244 e_nobufs:
1245 err = -ENOBUFS;
1246 goto done;
1247 e_neighbour:
1248 dst_free(&rt->dst);
1249 goto e_nobufs;
1250 }
1251
1252
1253 /*
1254 * N.B. The flags may be moved into the flowi at some future stage.
1255 */
__dn_route_output_key(struct dst_entry ** pprt,const struct flowidn * flp,int flags)1256 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags)
1257 {
1258 unsigned int hash = dn_hash(flp->saddr, flp->daddr);
1259 struct dn_route *rt = NULL;
1260
1261 if (!(flags & MSG_TRYHARD)) {
1262 rcu_read_lock_bh();
1263 for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
1264 rt = rcu_dereference_bh(rt->dst.dn_next)) {
1265 if ((flp->daddr == rt->fld.daddr) &&
1266 (flp->saddr == rt->fld.saddr) &&
1267 (flp->flowidn_mark == rt->fld.flowidn_mark) &&
1268 dn_is_output_route(rt) &&
1269 (rt->fld.flowidn_oif == flp->flowidn_oif)) {
1270 dst_use(&rt->dst, jiffies);
1271 rcu_read_unlock_bh();
1272 *pprt = &rt->dst;
1273 return 0;
1274 }
1275 }
1276 rcu_read_unlock_bh();
1277 }
1278
1279 return dn_route_output_slow(pprt, flp, flags);
1280 }
1281
dn_route_output_key(struct dst_entry ** pprt,struct flowidn * flp,int flags)1282 static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags)
1283 {
1284 int err;
1285
1286 err = __dn_route_output_key(pprt, flp, flags);
1287 if (err == 0 && flp->flowidn_proto) {
1288 *pprt = xfrm_lookup(&init_net, *pprt,
1289 flowidn_to_flowi(flp), NULL, 0);
1290 if (IS_ERR(*pprt)) {
1291 err = PTR_ERR(*pprt);
1292 *pprt = NULL;
1293 }
1294 }
1295 return err;
1296 }
1297
dn_route_output_sock(struct dst_entry __rcu ** pprt,struct flowidn * fl,struct sock * sk,int flags)1298 int dn_route_output_sock(struct dst_entry __rcu **pprt, struct flowidn *fl, struct sock *sk, int flags)
1299 {
1300 int err;
1301
1302 err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1303 if (err == 0 && fl->flowidn_proto) {
1304 *pprt = xfrm_lookup(&init_net, *pprt,
1305 flowidn_to_flowi(fl), sk, 0);
1306 if (IS_ERR(*pprt)) {
1307 err = PTR_ERR(*pprt);
1308 *pprt = NULL;
1309 }
1310 }
1311 return err;
1312 }
1313
dn_route_input_slow(struct sk_buff * skb)1314 static int dn_route_input_slow(struct sk_buff *skb)
1315 {
1316 struct dn_route *rt = NULL;
1317 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1318 struct net_device *in_dev = skb->dev;
1319 struct net_device *out_dev = NULL;
1320 struct dn_dev *dn_db;
1321 struct neighbour *neigh = NULL;
1322 unsigned int hash;
1323 int flags = 0;
1324 __le16 gateway = 0;
1325 __le16 local_src = 0;
1326 struct flowidn fld = {
1327 .daddr = cb->dst,
1328 .saddr = cb->src,
1329 .flowidn_scope = RT_SCOPE_UNIVERSE,
1330 .flowidn_mark = skb->mark,
1331 .flowidn_iif = skb->dev->ifindex,
1332 };
1333 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1334 int err = -EINVAL;
1335 int free_res = 0;
1336
1337 dev_hold(in_dev);
1338
1339 if ((dn_db = rcu_dereference(in_dev->dn_ptr)) == NULL)
1340 goto out;
1341
1342 /* Zero source addresses are not allowed */
1343 if (fld.saddr == 0)
1344 goto out;
1345
1346 /*
1347 * In this case we've just received a packet from a source
1348 * outside ourselves pretending to come from us. We don't
1349 * allow it any further to prevent routing loops, spoofing and
1350 * other nasties. Loopback packets already have the dst attached
1351 * so this only affects packets which have originated elsewhere.
1352 */
1353 err = -ENOTUNIQ;
1354 if (dn_dev_islocal(in_dev, cb->src))
1355 goto out;
1356
1357 err = dn_fib_lookup(&fld, &res);
1358 if (err) {
1359 if (err != -ESRCH)
1360 goto out;
1361 /*
1362 * Is the destination us ?
1363 */
1364 if (!dn_dev_islocal(in_dev, cb->dst))
1365 goto e_inval;
1366
1367 res.type = RTN_LOCAL;
1368 } else {
1369 __le16 src_map = fld.saddr;
1370 free_res = 1;
1371
1372 out_dev = DN_FIB_RES_DEV(res);
1373 if (out_dev == NULL) {
1374 net_crit_ratelimited("Bug in dn_route_input_slow() No output device\n");
1375 goto e_inval;
1376 }
1377 dev_hold(out_dev);
1378
1379 if (res.r)
1380 src_map = fld.saddr; /* no NAT support for now */
1381
1382 gateway = DN_FIB_RES_GW(res);
1383 if (res.type == RTN_NAT) {
1384 fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res);
1385 dn_fib_res_put(&res);
1386 free_res = 0;
1387 if (dn_fib_lookup(&fld, &res))
1388 goto e_inval;
1389 free_res = 1;
1390 if (res.type != RTN_UNICAST)
1391 goto e_inval;
1392 flags |= RTCF_DNAT;
1393 gateway = fld.daddr;
1394 }
1395 fld.saddr = src_map;
1396 }
1397
1398 switch(res.type) {
1399 case RTN_UNICAST:
1400 /*
1401 * Forwarding check here, we only check for forwarding
1402 * being turned off, if you want to only forward intra
1403 * area, its up to you to set the routing tables up
1404 * correctly.
1405 */
1406 if (dn_db->parms.forwarding == 0)
1407 goto e_inval;
1408
1409 if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
1410 dn_fib_select_multipath(&fld, &res);
1411
1412 /*
1413 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1414 * flag as a hint to set the intra-ethernet bit when
1415 * forwarding. If we've got NAT in operation, we don't do
1416 * this optimisation.
1417 */
1418 if (out_dev == in_dev && !(flags & RTCF_NAT))
1419 flags |= RTCF_DOREDIRECT;
1420
1421 local_src = DN_FIB_RES_PREFSRC(res);
1422
1423 case RTN_BLACKHOLE:
1424 case RTN_UNREACHABLE:
1425 break;
1426 case RTN_LOCAL:
1427 flags |= RTCF_LOCAL;
1428 fld.saddr = cb->dst;
1429 fld.daddr = cb->src;
1430
1431 /* Routing tables gave us a gateway */
1432 if (gateway)
1433 goto make_route;
1434
1435 /* Packet was intra-ethernet, so we know its on-link */
1436 if (cb->rt_flags & DN_RT_F_IE) {
1437 gateway = cb->src;
1438 goto make_route;
1439 }
1440
1441 /* Use the default router if there is one */
1442 neigh = neigh_clone(dn_db->router);
1443 if (neigh) {
1444 gateway = ((struct dn_neigh *)neigh)->addr;
1445 goto make_route;
1446 }
1447
1448 /* Close eyes and pray */
1449 gateway = cb->src;
1450 goto make_route;
1451 default:
1452 goto e_inval;
1453 }
1454
1455 make_route:
1456 rt = dst_alloc(&dn_dst_ops, out_dev, 0, DST_OBSOLETE_NONE, DST_HOST);
1457 if (rt == NULL)
1458 goto e_nobufs;
1459
1460 memset(&rt->fld, 0, sizeof(rt->fld));
1461 rt->rt_saddr = fld.saddr;
1462 rt->rt_daddr = fld.daddr;
1463 rt->rt_gateway = fld.daddr;
1464 if (gateway)
1465 rt->rt_gateway = gateway;
1466 rt->rt_local_src = local_src ? local_src : rt->rt_saddr;
1467
1468 rt->rt_dst_map = fld.daddr;
1469 rt->rt_src_map = fld.saddr;
1470
1471 rt->fld.saddr = cb->src;
1472 rt->fld.daddr = cb->dst;
1473 rt->fld.flowidn_oif = 0;
1474 rt->fld.flowidn_iif = in_dev->ifindex;
1475 rt->fld.flowidn_mark = fld.flowidn_mark;
1476
1477 rt->n = neigh;
1478 rt->dst.lastuse = jiffies;
1479 rt->dst.output = dn_rt_bug_sk;
1480 switch (res.type) {
1481 case RTN_UNICAST:
1482 rt->dst.input = dn_forward;
1483 break;
1484 case RTN_LOCAL:
1485 rt->dst.output = dn_output;
1486 rt->dst.input = dn_nsp_rx;
1487 rt->dst.dev = in_dev;
1488 flags |= RTCF_LOCAL;
1489 break;
1490 default:
1491 case RTN_UNREACHABLE:
1492 case RTN_BLACKHOLE:
1493 rt->dst.input = dst_discard;
1494 }
1495 rt->rt_flags = flags;
1496
1497 err = dn_rt_set_next_hop(rt, &res);
1498 if (err)
1499 goto e_neighbour;
1500
1501 hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
1502 dn_insert_route(rt, hash, &rt);
1503 skb_dst_set(skb, &rt->dst);
1504
1505 done:
1506 if (neigh)
1507 neigh_release(neigh);
1508 if (free_res)
1509 dn_fib_res_put(&res);
1510 dev_put(in_dev);
1511 if (out_dev)
1512 dev_put(out_dev);
1513 out:
1514 return err;
1515
1516 e_inval:
1517 err = -EINVAL;
1518 goto done;
1519
1520 e_nobufs:
1521 err = -ENOBUFS;
1522 goto done;
1523
1524 e_neighbour:
1525 dst_free(&rt->dst);
1526 goto done;
1527 }
1528
dn_route_input(struct sk_buff * skb)1529 static int dn_route_input(struct sk_buff *skb)
1530 {
1531 struct dn_route *rt;
1532 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1533 unsigned int hash = dn_hash(cb->src, cb->dst);
1534
1535 if (skb_dst(skb))
1536 return 0;
1537
1538 rcu_read_lock();
1539 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1540 rt = rcu_dereference(rt->dst.dn_next)) {
1541 if ((rt->fld.saddr == cb->src) &&
1542 (rt->fld.daddr == cb->dst) &&
1543 (rt->fld.flowidn_oif == 0) &&
1544 (rt->fld.flowidn_mark == skb->mark) &&
1545 (rt->fld.flowidn_iif == cb->iif)) {
1546 dst_use(&rt->dst, jiffies);
1547 rcu_read_unlock();
1548 skb_dst_set(skb, (struct dst_entry *)rt);
1549 return 0;
1550 }
1551 }
1552 rcu_read_unlock();
1553
1554 return dn_route_input_slow(skb);
1555 }
1556
dn_rt_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int event,int nowait,unsigned int flags)1557 static int dn_rt_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
1558 int event, int nowait, unsigned int flags)
1559 {
1560 struct dn_route *rt = (struct dn_route *)skb_dst(skb);
1561 struct rtmsg *r;
1562 struct nlmsghdr *nlh;
1563 long expires;
1564
1565 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags);
1566 if (!nlh)
1567 return -EMSGSIZE;
1568
1569 r = nlmsg_data(nlh);
1570 r->rtm_family = AF_DECnet;
1571 r->rtm_dst_len = 16;
1572 r->rtm_src_len = 0;
1573 r->rtm_tos = 0;
1574 r->rtm_table = RT_TABLE_MAIN;
1575 r->rtm_type = rt->rt_type;
1576 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1577 r->rtm_scope = RT_SCOPE_UNIVERSE;
1578 r->rtm_protocol = RTPROT_UNSPEC;
1579
1580 if (rt->rt_flags & RTCF_NOTIFY)
1581 r->rtm_flags |= RTM_F_NOTIFY;
1582
1583 if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN) < 0 ||
1584 nla_put_le16(skb, RTA_DST, rt->rt_daddr) < 0)
1585 goto errout;
1586
1587 if (rt->fld.saddr) {
1588 r->rtm_src_len = 16;
1589 if (nla_put_le16(skb, RTA_SRC, rt->fld.saddr) < 0)
1590 goto errout;
1591 }
1592 if (rt->dst.dev &&
1593 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex) < 0)
1594 goto errout;
1595
1596 /*
1597 * Note to self - change this if input routes reverse direction when
1598 * they deal only with inputs and not with replies like they do
1599 * currently.
1600 */
1601 if (nla_put_le16(skb, RTA_PREFSRC, rt->rt_local_src) < 0)
1602 goto errout;
1603
1604 if (rt->rt_daddr != rt->rt_gateway &&
1605 nla_put_le16(skb, RTA_GATEWAY, rt->rt_gateway) < 0)
1606 goto errout;
1607
1608 if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
1609 goto errout;
1610
1611 expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
1612 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires,
1613 rt->dst.error) < 0)
1614 goto errout;
1615
1616 if (dn_is_input_route(rt) &&
1617 nla_put_u32(skb, RTA_IIF, rt->fld.flowidn_iif) < 0)
1618 goto errout;
1619
1620 return nlmsg_end(skb, nlh);
1621
1622 errout:
1623 nlmsg_cancel(skb, nlh);
1624 return -EMSGSIZE;
1625 }
1626
1627 const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
1628 [RTA_DST] = { .type = NLA_U16 },
1629 [RTA_SRC] = { .type = NLA_U16 },
1630 [RTA_IIF] = { .type = NLA_U32 },
1631 [RTA_OIF] = { .type = NLA_U32 },
1632 [RTA_GATEWAY] = { .type = NLA_U16 },
1633 [RTA_PRIORITY] = { .type = NLA_U32 },
1634 [RTA_PREFSRC] = { .type = NLA_U16 },
1635 [RTA_METRICS] = { .type = NLA_NESTED },
1636 [RTA_MULTIPATH] = { .type = NLA_NESTED },
1637 [RTA_TABLE] = { .type = NLA_U32 },
1638 [RTA_MARK] = { .type = NLA_U32 },
1639 };
1640
1641 /*
1642 * This is called by both endnodes and routers now.
1643 */
dn_cache_getroute(struct sk_buff * in_skb,struct nlmsghdr * nlh)1644 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
1645 {
1646 struct net *net = sock_net(in_skb->sk);
1647 struct rtmsg *rtm = nlmsg_data(nlh);
1648 struct dn_route *rt = NULL;
1649 struct dn_skb_cb *cb;
1650 int err;
1651 struct sk_buff *skb;
1652 struct flowidn fld;
1653 struct nlattr *tb[RTA_MAX+1];
1654
1655 if (!net_eq(net, &init_net))
1656 return -EINVAL;
1657
1658 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_dn_policy);
1659 if (err < 0)
1660 return err;
1661
1662 memset(&fld, 0, sizeof(fld));
1663 fld.flowidn_proto = DNPROTO_NSP;
1664
1665 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1666 if (skb == NULL)
1667 return -ENOBUFS;
1668 skb_reset_mac_header(skb);
1669 cb = DN_SKB_CB(skb);
1670
1671 if (tb[RTA_SRC])
1672 fld.saddr = nla_get_le16(tb[RTA_SRC]);
1673
1674 if (tb[RTA_DST])
1675 fld.daddr = nla_get_le16(tb[RTA_DST]);
1676
1677 if (tb[RTA_IIF])
1678 fld.flowidn_iif = nla_get_u32(tb[RTA_IIF]);
1679
1680 if (fld.flowidn_iif) {
1681 struct net_device *dev;
1682 dev = __dev_get_by_index(&init_net, fld.flowidn_iif);
1683 if (!dev || !dev->dn_ptr) {
1684 kfree_skb(skb);
1685 return -ENODEV;
1686 }
1687 skb->protocol = htons(ETH_P_DNA_RT);
1688 skb->dev = dev;
1689 cb->src = fld.saddr;
1690 cb->dst = fld.daddr;
1691 local_bh_disable();
1692 err = dn_route_input(skb);
1693 local_bh_enable();
1694 memset(cb, 0, sizeof(struct dn_skb_cb));
1695 rt = (struct dn_route *)skb_dst(skb);
1696 if (!err && -rt->dst.error)
1697 err = rt->dst.error;
1698 } else {
1699 if (tb[RTA_OIF])
1700 fld.flowidn_oif = nla_get_u32(tb[RTA_OIF]);
1701
1702 err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
1703 }
1704
1705 skb->dev = NULL;
1706 if (err)
1707 goto out_free;
1708 skb_dst_set(skb, &rt->dst);
1709 if (rtm->rtm_flags & RTM_F_NOTIFY)
1710 rt->rt_flags |= RTCF_NOTIFY;
1711
1712 err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1713
1714 if (err == 0)
1715 goto out_free;
1716 if (err < 0) {
1717 err = -EMSGSIZE;
1718 goto out_free;
1719 }
1720
1721 return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).portid);
1722
1723 out_free:
1724 kfree_skb(skb);
1725 return err;
1726 }
1727
1728 /*
1729 * For routers, this is called from dn_fib_dump, but for endnodes its
1730 * called directly from the rtnetlink dispatch table.
1731 */
dn_cache_dump(struct sk_buff * skb,struct netlink_callback * cb)1732 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1733 {
1734 struct net *net = sock_net(skb->sk);
1735 struct dn_route *rt;
1736 int h, s_h;
1737 int idx, s_idx;
1738 struct rtmsg *rtm;
1739
1740 if (!net_eq(net, &init_net))
1741 return 0;
1742
1743 if (nlmsg_len(cb->nlh) < sizeof(struct rtmsg))
1744 return -EINVAL;
1745
1746 rtm = nlmsg_data(cb->nlh);
1747 if (!(rtm->rtm_flags & RTM_F_CLONED))
1748 return 0;
1749
1750 s_h = cb->args[0];
1751 s_idx = idx = cb->args[1];
1752 for(h = 0; h <= dn_rt_hash_mask; h++) {
1753 if (h < s_h)
1754 continue;
1755 if (h > s_h)
1756 s_idx = 0;
1757 rcu_read_lock_bh();
1758 for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
1759 rt;
1760 rt = rcu_dereference_bh(rt->dst.dn_next), idx++) {
1761 if (idx < s_idx)
1762 continue;
1763 skb_dst_set(skb, dst_clone(&rt->dst));
1764 if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).portid,
1765 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1766 1, NLM_F_MULTI) <= 0) {
1767 skb_dst_drop(skb);
1768 rcu_read_unlock_bh();
1769 goto done;
1770 }
1771 skb_dst_drop(skb);
1772 }
1773 rcu_read_unlock_bh();
1774 }
1775
1776 done:
1777 cb->args[0] = h;
1778 cb->args[1] = idx;
1779 return skb->len;
1780 }
1781
1782 #ifdef CONFIG_PROC_FS
1783 struct dn_rt_cache_iter_state {
1784 int bucket;
1785 };
1786
dn_rt_cache_get_first(struct seq_file * seq)1787 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1788 {
1789 struct dn_route *rt = NULL;
1790 struct dn_rt_cache_iter_state *s = seq->private;
1791
1792 for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1793 rcu_read_lock_bh();
1794 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1795 if (rt)
1796 break;
1797 rcu_read_unlock_bh();
1798 }
1799 return rt;
1800 }
1801
dn_rt_cache_get_next(struct seq_file * seq,struct dn_route * rt)1802 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1803 {
1804 struct dn_rt_cache_iter_state *s = seq->private;
1805
1806 rt = rcu_dereference_bh(rt->dst.dn_next);
1807 while (!rt) {
1808 rcu_read_unlock_bh();
1809 if (--s->bucket < 0)
1810 break;
1811 rcu_read_lock_bh();
1812 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1813 }
1814 return rt;
1815 }
1816
dn_rt_cache_seq_start(struct seq_file * seq,loff_t * pos)1817 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1818 {
1819 struct dn_route *rt = dn_rt_cache_get_first(seq);
1820
1821 if (rt) {
1822 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1823 --*pos;
1824 }
1825 return *pos ? NULL : rt;
1826 }
1827
dn_rt_cache_seq_next(struct seq_file * seq,void * v,loff_t * pos)1828 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1829 {
1830 struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1831 ++*pos;
1832 return rt;
1833 }
1834
dn_rt_cache_seq_stop(struct seq_file * seq,void * v)1835 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1836 {
1837 if (v)
1838 rcu_read_unlock_bh();
1839 }
1840
dn_rt_cache_seq_show(struct seq_file * seq,void * v)1841 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1842 {
1843 struct dn_route *rt = v;
1844 char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1845
1846 seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1847 rt->dst.dev ? rt->dst.dev->name : "*",
1848 dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
1849 dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
1850 atomic_read(&rt->dst.__refcnt),
1851 rt->dst.__use, 0);
1852 return 0;
1853 }
1854
1855 static const struct seq_operations dn_rt_cache_seq_ops = {
1856 .start = dn_rt_cache_seq_start,
1857 .next = dn_rt_cache_seq_next,
1858 .stop = dn_rt_cache_seq_stop,
1859 .show = dn_rt_cache_seq_show,
1860 };
1861
dn_rt_cache_seq_open(struct inode * inode,struct file * file)1862 static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1863 {
1864 return seq_open_private(file, &dn_rt_cache_seq_ops,
1865 sizeof(struct dn_rt_cache_iter_state));
1866 }
1867
1868 static const struct file_operations dn_rt_cache_seq_fops = {
1869 .owner = THIS_MODULE,
1870 .open = dn_rt_cache_seq_open,
1871 .read = seq_read,
1872 .llseek = seq_lseek,
1873 .release = seq_release_private,
1874 };
1875
1876 #endif /* CONFIG_PROC_FS */
1877
dn_route_init(void)1878 void __init dn_route_init(void)
1879 {
1880 int i, goal, order;
1881
1882 dn_dst_ops.kmem_cachep =
1883 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1884 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1885 dst_entries_init(&dn_dst_ops);
1886 setup_timer(&dn_route_timer, dn_dst_check_expire, 0);
1887 dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1888 add_timer(&dn_route_timer);
1889
1890 goal = totalram_pages >> (26 - PAGE_SHIFT);
1891
1892 for(order = 0; (1UL << order) < goal; order++)
1893 /* NOTHING */;
1894
1895 /*
1896 * Only want 1024 entries max, since the table is very, very unlikely
1897 * to be larger than that.
1898 */
1899 while(order && ((((1UL << order) * PAGE_SIZE) /
1900 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1901 order--;
1902
1903 do {
1904 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1905 sizeof(struct dn_rt_hash_bucket);
1906 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1907 dn_rt_hash_mask--;
1908 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1909 __get_free_pages(GFP_ATOMIC, order);
1910 } while (dn_rt_hash_table == NULL && --order > 0);
1911
1912 if (!dn_rt_hash_table)
1913 panic("Failed to allocate DECnet route cache hash table\n");
1914
1915 printk(KERN_INFO
1916 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1917 dn_rt_hash_mask,
1918 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1919
1920 dn_rt_hash_mask--;
1921 for(i = 0; i <= dn_rt_hash_mask; i++) {
1922 spin_lock_init(&dn_rt_hash_table[i].lock);
1923 dn_rt_hash_table[i].chain = NULL;
1924 }
1925
1926 dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1927
1928 proc_create("decnet_cache", S_IRUGO, init_net.proc_net,
1929 &dn_rt_cache_seq_fops);
1930
1931 #ifdef CONFIG_DECNET_ROUTER
1932 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1933 dn_fib_dump, NULL);
1934 #else
1935 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1936 dn_cache_dump, NULL);
1937 #endif
1938 }
1939
dn_route_cleanup(void)1940 void __exit dn_route_cleanup(void)
1941 {
1942 del_timer(&dn_route_timer);
1943 dn_run_flush(0);
1944
1945 remove_proc_entry("decnet_cache", init_net.proc_net);
1946 dst_entries_destroy(&dn_dst_ops);
1947 }
1948
1949