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[net-next-2.6.git] / net / decnet / dn_route.c
CommitLineData
1da177e4
LT		 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
429eb0fa 46
1da177e4
LT		 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
1da177e4
LT		 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 <net/sock.h>
70#include <linux/mm.h>
71#include <linux/proc_fs.h>
72#include <linux/seq_file.h>
73#include <linux/init.h>
74#include <linux/rtnetlink.h>
75#include <linux/string.h>
76#include <linux/netfilter_decnet.h>
77#include <linux/rcupdate.h>
78#include <linux/times.h>
79#include <asm/errno.h>
dc5fc579 80#include <net/netlink.h>
1da177e4
LT		 81#include <net/neighbour.h>
82#include <net/dst.h>
83#include <net/flow.h>
a8731cbf 84#include <net/fib_rules.h>
1da177e4
LT		 85#include <net/dn.h>
86#include <net/dn_dev.h>
87#include <net/dn_nsp.h>
88#include <net/dn_route.h>
89#include <net/dn_neigh.h>
90#include <net/dn_fib.h>
91
92struct dn_rt_hash_bucket
93{
94 struct dn_route *chain;
95 spinlock_t lock;
96} __attribute__((__aligned__(8)));
97
98extern struct neigh_table dn_neigh_table;
99
100
101static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
102
103static const int dn_rt_min_delay = 2 * HZ;
104static const int dn_rt_max_delay = 10 * HZ;
105static const int dn_rt_mtu_expires = 10 * 60 * HZ;
106
107static unsigned long dn_rt_deadline;
108
109static int dn_dst_gc(void);
110static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
111static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
112static void dn_dst_link_failure(struct sk_buff *);
113static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
114static int dn_route_input(struct sk_buff *);
115static void dn_run_flush(unsigned long dummy);
116
117static struct dn_rt_hash_bucket *dn_rt_hash_table;
118static unsigned dn_rt_hash_mask;
119
120static struct timer_list dn_route_timer;
8d06afab 121static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
1da177e4
LT		 122int decnet_dst_gc_interval = 2;
123
124static struct dst_ops dn_dst_ops = {
125 .family = PF_DECnet,
126 .protocol = __constant_htons(ETH_P_DNA_RT),
127 .gc_thresh = 128,
128 .gc = dn_dst_gc,
129 .check = dn_dst_check,
130 .negative_advice = dn_dst_negative_advice,
131 .link_failure = dn_dst_link_failure,
132 .update_pmtu = dn_dst_update_pmtu,
133 .entry_size = sizeof(struct dn_route),
134 .entries = ATOMIC_INIT(0),
135};
136
c4ea94ab 137static __inline__ unsigned dn_hash(__le16 src, __le16 dst)
1da177e4 138{
c4ea94ab 139 __u16 tmp = (__u16 __force)(src ^ dst);
1da177e4
LT		 140 tmp ^= (tmp >> 3);
141 tmp ^= (tmp >> 5);
142 tmp ^= (tmp >> 10);
143 return dn_rt_hash_mask & (unsigned)tmp;
144}
145
146static inline void dnrt_free(struct dn_route *rt)
147{
148 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
149}
150
151static inline void dnrt_drop(struct dn_route *rt)
152{
34001127 153 dst_release(&rt->u.dst);
1da177e4
LT		 154 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
155}
156
157static void dn_dst_check_expire(unsigned long dummy)
158{
159 int i;
160 struct dn_route *rt, **rtp;
161 unsigned long now = jiffies;
162 unsigned long expire = 120 * HZ;
163
164 for(i = 0; i <= dn_rt_hash_mask; i++) {
165 rtp = &dn_rt_hash_table[i].chain;
166
167 spin_lock(&dn_rt_hash_table[i].lock);
168 while((rt=*rtp) != NULL) {
169 if (atomic_read(&rt->u.dst.__refcnt) ||
170 (now - rt->u.dst.lastuse) < expire) {
0c195c3f 171 rtp = &rt->u.dst.dn_next;
1da177e4
LT		 172 continue;
173 }
0c195c3f
ED		 174 *rtp = rt->u.dst.dn_next;
175 rt->u.dst.dn_next = NULL;
1da177e4
LT		 176 dnrt_free(rt);
177 }
178 spin_unlock(&dn_rt_hash_table[i].lock);
179
180 if ((jiffies - now) > 0)
181 break;
182 }
183
184 mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ);
185}
186
187static int dn_dst_gc(void)
188{
189 struct dn_route *rt, **rtp;
190 int i;
191 unsigned long now = jiffies;
192 unsigned long expire = 10 * HZ;
193
194 for(i = 0; i <= dn_rt_hash_mask; i++) {
195
196 spin_lock_bh(&dn_rt_hash_table[i].lock);
197 rtp = &dn_rt_hash_table[i].chain;
198
199 while((rt=*rtp) != NULL) {
200 if (atomic_read(&rt->u.dst.__refcnt) ||
201 (now - rt->u.dst.lastuse) < expire) {
0c195c3f 202 rtp = &rt->u.dst.dn_next;
1da177e4
LT		 203 continue;
204 }
0c195c3f
ED		 205 *rtp = rt->u.dst.dn_next;
206 rt->u.dst.dn_next = NULL;
1da177e4
LT		 207 dnrt_drop(rt);
208 break;
209 }
210 spin_unlock_bh(&dn_rt_hash_table[i].lock);
211 }
212
213 return 0;
214}
215
216/*
217 * The decnet standards don't impose a particular minimum mtu, what they
218 * do insist on is that the routing layer accepts a datagram of at least
219 * 230 bytes long. Here we have to subtract the routing header length from
220 * 230 to get the minimum acceptable mtu. If there is no neighbour, then we
221 * assume the worst and use a long header size.
222 *
223 * We update both the mtu and the advertised mss (i.e. the segment size we
224 * advertise to the other end).
225 */
226static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu)
227{
228 u32 min_mtu = 230;
229 struct dn_dev *dn = dst->neighbour ?
230 (struct dn_dev *)dst->neighbour->dev->dn_ptr : NULL;
231
232 if (dn && dn->use_long == 0)
233 min_mtu -= 6;
234 else
235 min_mtu -= 21;
236
237 if (dst->metrics[RTAX_MTU-1] > mtu && mtu >= min_mtu) {
238 if (!(dst_metric_locked(dst, RTAX_MTU))) {
239 dst->metrics[RTAX_MTU-1] = mtu;
240 dst_set_expires(dst, dn_rt_mtu_expires);
241 }
242 if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
243 u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
244 if (dst->metrics[RTAX_ADVMSS-1] > mss)
245 dst->metrics[RTAX_ADVMSS-1] = mss;
246 }
247 }
248}
249
429eb0fa 250/*
1da177e4
LT		 251 * When a route has been marked obsolete. (e.g. routing cache flush)
252 */
253static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
254{
255 return NULL;
256}
257
258static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
259{
260 dst_release(dst);
261 return NULL;
262}
263
264static void dn_dst_link_failure(struct sk_buff *skb)
265{
266 return;
267}
268
269static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
270{
8238b218
DM		 271 return ((fl1->nl_u.dn_u.daddr ^ fl2->nl_u.dn_u.daddr) |
272 (fl1->nl_u.dn_u.saddr ^ fl2->nl_u.dn_u.saddr) |
47dcf0cb 273 (fl1->mark ^ fl2->mark) |
8238b218
DM		 274 (fl1->nl_u.dn_u.scope ^ fl2->nl_u.dn_u.scope) |
275 (fl1->oif ^ fl2->oif) |
276 (fl1->iif ^ fl2->iif)) == 0;
1da177e4
LT		 277}
278
279static int dn_insert_route(struct dn_route *rt, unsigned hash, struct dn_route **rp)
280{
281 struct dn_route *rth, **rthp;
282 unsigned long now = jiffies;
283
284 rthp = &dn_rt_hash_table[hash].chain;
285
286 spin_lock_bh(&dn_rt_hash_table[hash].lock);
287 while((rth = *rthp) != NULL) {
288 if (compare_keys(&rth->fl, &rt->fl)) {
289 /* Put it first */
0c195c3f
ED		 290 *rthp = rth->u.dst.dn_next;
291 rcu_assign_pointer(rth->u.dst.dn_next,
1da177e4
LT		 292 dn_rt_hash_table[hash].chain);
293 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
294
295 rth->u.dst.__use++;
296 dst_hold(&rth->u.dst);
297 rth->u.dst.lastuse = now;
298 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
299
300 dnrt_drop(rt);
301 *rp = rth;
302 return 0;
303 }
0c195c3f 304 rthp = &rth->u.dst.dn_next;
1da177e4
LT		 305 }
306
0c195c3f 307 rcu_assign_pointer(rt->u.dst.dn_next, dn_rt_hash_table[hash].chain);
1da177e4 308 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
429eb0fa 309
1da177e4
LT		 310 dst_hold(&rt->u.dst);
311 rt->u.dst.__use++;
312 rt->u.dst.lastuse = now;
313 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
314 *rp = rt;
315 return 0;
316}
317
318void dn_run_flush(unsigned long dummy)
319{
320 int i;
321 struct dn_route *rt, *next;
322
323 for(i = 0; i < dn_rt_hash_mask; i++) {
324 spin_lock_bh(&dn_rt_hash_table[i].lock);
325
326 if ((rt = xchg(&dn_rt_hash_table[i].chain, NULL)) == NULL)
327 goto nothing_to_declare;
328
329 for(; rt; rt=next) {
0c195c3f
ED		 330 next = rt->u.dst.dn_next;
331 rt->u.dst.dn_next = NULL;
1da177e4
LT		 332 dst_free((struct dst_entry *)rt);
333 }
334
335nothing_to_declare:
336 spin_unlock_bh(&dn_rt_hash_table[i].lock);
337 }
338}
339
340static DEFINE_SPINLOCK(dn_rt_flush_lock);
341
342void dn_rt_cache_flush(int delay)
343{
344 unsigned long now = jiffies;
345 int user_mode = !in_interrupt();
346
347 if (delay < 0)
348 delay = dn_rt_min_delay;
349
350 spin_lock_bh(&dn_rt_flush_lock);
351
352 if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
353 long tmo = (long)(dn_rt_deadline - now);
354
355 if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
356 tmo = 0;
357
358 if (delay > tmo)
359 delay = tmo;
360 }
361
362 if (delay <= 0) {
363 spin_unlock_bh(&dn_rt_flush_lock);
364 dn_run_flush(0);
365 return;
366 }
367
368 if (dn_rt_deadline == 0)
369 dn_rt_deadline = now + dn_rt_max_delay;
370
371 dn_rt_flush_timer.expires = now + delay;
372 add_timer(&dn_rt_flush_timer);
373 spin_unlock_bh(&dn_rt_flush_lock);
374}
375
376/**
377 * dn_return_short - Return a short packet to its sender
378 * @skb: The packet to return
379 *
380 */
381static int dn_return_short(struct sk_buff *skb)
382{
383 struct dn_skb_cb *cb;
384 unsigned char *ptr;
c4ea94ab
SW		 385 __le16 *src;
386 __le16 *dst;
387 __le16 tmp;
1da177e4
LT		 388
389 /* Add back headers */
d56f90a7 390 skb_push(skb, skb->data - skb_network_header(skb));
1da177e4
LT		 391
392 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
393 return NET_RX_DROP;
394
395 cb = DN_SKB_CB(skb);
396 /* Skip packet length and point to flags */
397 ptr = skb->data + 2;
398 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
399
c4ea94ab 400 dst = (__le16 *)ptr;
1da177e4 401 ptr += 2;
c4ea94ab 402 src = (__le16 *)ptr;
1da177e4
LT		 403 ptr += 2;
404 *ptr = 0; /* Zero hop count */
405
406 /* Swap source and destination */
407 tmp = *src;
408 *src = *dst;
409 *dst = tmp;
410
411 skb->pkt_type = PACKET_OUTGOING;
412 dn_rt_finish_output(skb, NULL, NULL);
413 return NET_RX_SUCCESS;
414}
415
416/**
417 * dn_return_long - Return a long packet to its sender
418 * @skb: The long format packet to return
419 *
420 */
421static int dn_return_long(struct sk_buff *skb)
422{
423 struct dn_skb_cb *cb;
424 unsigned char *ptr;
425 unsigned char *src_addr, *dst_addr;
426 unsigned char tmp[ETH_ALEN];
427
428 /* Add back all headers */
d56f90a7 429 skb_push(skb, skb->data - skb_network_header(skb));
1da177e4
LT		 430
431 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
432 return NET_RX_DROP;
433
434 cb = DN_SKB_CB(skb);
435 /* Ignore packet length and point to flags */
436 ptr = skb->data + 2;
437
438 /* Skip padding */
439 if (*ptr & DN_RT_F_PF) {
440 char padlen = (*ptr & ~DN_RT_F_PF);
441 ptr += padlen;
442 }
443
444 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
445 ptr += 2;
446 dst_addr = ptr;
447 ptr += 8;
448 src_addr = ptr;
449 ptr += 6;
450 *ptr = 0; /* Zero hop count */
451
452 /* Swap source and destination */
453 memcpy(tmp, src_addr, ETH_ALEN);
454 memcpy(src_addr, dst_addr, ETH_ALEN);
455 memcpy(dst_addr, tmp, ETH_ALEN);
456
457 skb->pkt_type = PACKET_OUTGOING;
458 dn_rt_finish_output(skb, dst_addr, src_addr);
459 return NET_RX_SUCCESS;
460}
461
462/**
463 * dn_route_rx_packet - Try and find a route for an incoming packet
464 * @skb: The packet to find a route for
465 *
466 * Returns: result of input function if route is found, error code otherwise
467 */
468static int dn_route_rx_packet(struct sk_buff *skb)
469{
470 struct dn_skb_cb *cb = DN_SKB_CB(skb);
471 int err;
472
473 if ((err = dn_route_input(skb)) == 0)
474 return dst_input(skb);
475
476 if (decnet_debug_level & 4) {
477 char *devname = skb->dev ? skb->dev->name : "???";
478 struct dn_skb_cb *cb = DN_SKB_CB(skb);
479 printk(KERN_DEBUG
480 "DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
c4ea94ab
SW		 481 (int)cb->rt_flags, devname, skb->len,
482 dn_ntohs(cb->src), dn_ntohs(cb->dst),
1da177e4
LT		 483 err, skb->pkt_type);
484 }
485
486 if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
487 switch(cb->rt_flags & DN_RT_PKT_MSK) {
488 case DN_RT_PKT_SHORT:
489 return dn_return_short(skb);
490 case DN_RT_PKT_LONG:
491 return dn_return_long(skb);
492 }
493 }
494
495 kfree_skb(skb);
496 return NET_RX_DROP;
497}
498
499static int dn_route_rx_long(struct sk_buff *skb)
500{
501 struct dn_skb_cb *cb = DN_SKB_CB(skb);
502 unsigned char *ptr = skb->data;
503
504 if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
505 goto drop_it;
506
507 skb_pull(skb, 20);
badff6d0 508 skb_reset_transport_header(skb);
1da177e4 509
429eb0fa
YH		 510 /* Destination info */
511 ptr += 2;
c4ea94ab 512 cb->dst = dn_eth2dn(ptr);
429eb0fa
YH		 513 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
514 goto drop_it;
515 ptr += 6;
1da177e4
LT		 516
517
429eb0fa
YH		 518 /* Source info */
519 ptr += 2;
c4ea94ab 520 cb->src = dn_eth2dn(ptr);
429eb0fa
YH		 521 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
522 goto drop_it;
523 ptr += 6;
524 /* Other junk */
525 ptr++;
526 cb->hops = *ptr++; /* Visit Count */
1da177e4
LT		 527
528 return NF_HOOK(PF_DECnet, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet);
529
530drop_it:
531 kfree_skb(skb);
532 return NET_RX_DROP;
533}
534
535
536
537static int dn_route_rx_short(struct sk_buff *skb)
538{
539 struct dn_skb_cb *cb = DN_SKB_CB(skb);
540 unsigned char *ptr = skb->data;
541
542 if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
543 goto drop_it;
544
545 skb_pull(skb, 5);
badff6d0 546 skb_reset_transport_header(skb);
1da177e4 547
c4ea94ab 548 cb->dst = *(__le16 *)ptr;
429eb0fa
YH		 549 ptr += 2;
550 cb->src = *(__le16 *)ptr;
551 ptr += 2;
552 cb->hops = *ptr & 0x3f;
1da177e4
LT		 553
554 return NF_HOOK(PF_DECnet, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet);
555
556drop_it:
429eb0fa
YH		 557 kfree_skb(skb);
558 return NET_RX_DROP;
1da177e4
LT		 559}
560
561static int dn_route_discard(struct sk_buff *skb)
562{
563 /*
564 * I know we drop the packet here, but thats considered success in
565 * this case
566 */
567 kfree_skb(skb);
568 return NET_RX_SUCCESS;
569}
570
571static int dn_route_ptp_hello(struct sk_buff *skb)
572{
573 dn_dev_hello(skb);
574 dn_neigh_pointopoint_hello(skb);
575 return NET_RX_SUCCESS;
576}
577
f2ccd8fa 578int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
1da177e4
LT		 579{
580 struct dn_skb_cb *cb;
581 unsigned char flags = 0;
c4ea94ab 582 __u16 len = dn_ntohs(*(__le16 *)skb->data);
1da177e4
LT		 583 struct dn_dev *dn = (struct dn_dev *)dev->dn_ptr;
584 unsigned char padlen = 0;
585
586 if (dn == NULL)
587 goto dump_it;
588
589 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
590 goto out;
591
592 if (!pskb_may_pull(skb, 3))
593 goto dump_it;
594
595 skb_pull(skb, 2);
596
597 if (len > skb->len)
598 goto dump_it;
599
600 skb_trim(skb, len);
601
602 flags = *skb->data;
603
604 cb = DN_SKB_CB(skb);
605 cb->stamp = jiffies;
606 cb->iif = dev->ifindex;
607
608 /*
609 * If we have padding, remove it.
610 */
611 if (flags & DN_RT_F_PF) {
612 padlen = flags & ~DN_RT_F_PF;
613 if (!pskb_may_pull(skb, padlen + 1))
614 goto dump_it;
615 skb_pull(skb, padlen);
616 flags = *skb->data;
617 }
618
c1d2bbe1 619 skb_reset_network_header(skb);
1da177e4
LT		 620
621 /*
622 * Weed out future version DECnet
623 */
624 if (flags & DN_RT_F_VER)
625 goto dump_it;
626
627 cb->rt_flags = flags;
628
629 if (decnet_debug_level & 1)
429eb0fa 630 printk(KERN_DEBUG
1da177e4 631 "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
429eb0fa 632 (int)flags, (dev) ? dev->name : "???", len, skb->len,
1da177e4
LT		 633 padlen);
634
429eb0fa 635 if (flags & DN_RT_PKT_CNTL) {
364c6bad 636 if (unlikely(skb_linearize(skb)))
1da177e4
LT		 637 goto dump_it;
638
429eb0fa
YH		 639 switch(flags & DN_RT_CNTL_MSK) {
640 case DN_RT_PKT_INIT:
1da177e4
LT		 641 dn_dev_init_pkt(skb);
642 break;
429eb0fa 643 case DN_RT_PKT_VERI:
1da177e4
LT		 644 dn_dev_veri_pkt(skb);
645 break;
646 }
647
648 if (dn->parms.state != DN_DEV_S_RU)
649 goto dump_it;
650
651 switch(flags & DN_RT_CNTL_MSK) {
429eb0fa 652 case DN_RT_PKT_HELO:
1da177e4
LT		 653 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_route_ptp_hello);
654
429eb0fa
YH		 655 case DN_RT_PKT_L1RT:
656 case DN_RT_PKT_L2RT:
657 return NF_HOOK(PF_DECnet, NF_DN_ROUTE, skb, skb->dev, NULL, dn_route_discard);
658 case DN_RT_PKT_ERTH:
1da177e4
LT		 659 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_router_hello);
660
429eb0fa 661 case DN_RT_PKT_EEDH:
1da177e4 662 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_endnode_hello);
429eb0fa
YH		 663 }
664 } else {
1da177e4
LT		 665 if (dn->parms.state != DN_DEV_S_RU)
666 goto dump_it;
667
668 skb_pull(skb, 1); /* Pull flags */
669
429eb0fa
YH		 670 switch(flags & DN_RT_PKT_MSK) {
671 case DN_RT_PKT_LONG:
672 return dn_route_rx_long(skb);
673 case DN_RT_PKT_SHORT:
674 return dn_route_rx_short(skb);
1da177e4 675 }
429eb0fa 676 }
1da177e4
LT		 677
678dump_it:
679 kfree_skb(skb);
680out:
681 return NET_RX_DROP;
682}
683
684static int dn_output(struct sk_buff *skb)
685{
686 struct dst_entry *dst = skb->dst;
687 struct dn_route *rt = (struct dn_route *)dst;
688 struct net_device *dev = dst->dev;
689 struct dn_skb_cb *cb = DN_SKB_CB(skb);
690 struct neighbour *neigh;
691
692 int err = -EINVAL;
693
694 if ((neigh = dst->neighbour) == NULL)
695 goto error;
696
697 skb->dev = dev;
698
699 cb->src = rt->rt_saddr;
700 cb->dst = rt->rt_daddr;
701
702 /*
703 * Always set the Intra-Ethernet bit on all outgoing packets
704 * originated on this node. Only valid flag from upper layers
705 * is return-to-sender-requested. Set hop count to 0 too.
706 */
707 cb->rt_flags &= ~DN_RT_F_RQR;
708 cb->rt_flags |= DN_RT_F_IE;
709 cb->hops = 0;
710
711 return NF_HOOK(PF_DECnet, NF_DN_LOCAL_OUT, skb, NULL, dev, neigh->output);
712
713error:
714 if (net_ratelimit())
715 printk(KERN_DEBUG "dn_output: This should not happen\n");
716
717 kfree_skb(skb);
718
719 return err;
720}
721
722static int dn_forward(struct sk_buff *skb)
723{
724 struct dn_skb_cb *cb = DN_SKB_CB(skb);
725 struct dst_entry *dst = skb->dst;
726 struct dn_dev *dn_db = dst->dev->dn_ptr;
727 struct dn_route *rt;
728 struct neighbour *neigh = dst->neighbour;
729 int header_len;
730#ifdef CONFIG_NETFILTER
731 struct net_device *dev = skb->dev;
732#endif
733
734 if (skb->pkt_type != PACKET_HOST)
735 goto drop;
736
737 /* Ensure that we have enough space for headers */
738 rt = (struct dn_route *)skb->dst;
739 header_len = dn_db->use_long ? 21 : 6;
740 if (skb_cow(skb, LL_RESERVED_SPACE(rt->u.dst.dev)+header_len))
741 goto drop;
742
743 /*
744 * Hop count exceeded.
745 */
746 if (++cb->hops > 30)
747 goto drop;
748
749 skb->dev = rt->u.dst.dev;
750
751 /*
752 * If packet goes out same interface it came in on, then set
753 * the Intra-Ethernet bit. This has no effect for short
754 * packets, so we don't need to test for them here.
755 */
756 cb->rt_flags &= ~DN_RT_F_IE;
757 if (rt->rt_flags & RTCF_DOREDIRECT)
758 cb->rt_flags |= DN_RT_F_IE;
759
760 return NF_HOOK(PF_DECnet, NF_DN_FORWARD, skb, dev, skb->dev, neigh->output);
761
762drop:
763 kfree_skb(skb);
764 return NET_RX_DROP;
765}
766
767/*
768 * Drop packet. This is used for endnodes and for
769 * when we should not be forwarding packets from
770 * this dest.
771 */
772static int dn_blackhole(struct sk_buff *skb)
773{
774 kfree_skb(skb);
775 return NET_RX_DROP;
776}
777
778/*
779 * Used to catch bugs. This should never normally get
780 * called.
781 */
782static int dn_rt_bug(struct sk_buff *skb)
783{
784 if (net_ratelimit()) {
785 struct dn_skb_cb *cb = DN_SKB_CB(skb);
786
787 printk(KERN_DEBUG "dn_rt_bug: skb from:%04x to:%04x\n",
c4ea94ab 788 dn_ntohs(cb->src), dn_ntohs(cb->dst));
1da177e4
LT		 789 }
790
791 kfree_skb(skb);
792
793 return NET_RX_BAD;
794}
795
796static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
797{
798 struct dn_fib_info *fi = res->fi;
799 struct net_device *dev = rt->u.dst.dev;
800 struct neighbour *n;
801 unsigned mss;
802
803 if (fi) {
804 if (DN_FIB_RES_GW(*res) &&
805 DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
806 rt->rt_gateway = DN_FIB_RES_GW(*res);
807 memcpy(rt->u.dst.metrics, fi->fib_metrics,
808 sizeof(rt->u.dst.metrics));
809 }
810 rt->rt_type = res->type;
811
812 if (dev != NULL && rt->u.dst.neighbour == NULL) {
813 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
814 if (IS_ERR(n))
815 return PTR_ERR(n);
816 rt->u.dst.neighbour = n;
817 }
818
429eb0fa
YH		 819 if (rt->u.dst.metrics[RTAX_MTU-1] == 0 ||
820 rt->u.dst.metrics[RTAX_MTU-1] > rt->u.dst.dev->mtu)
1da177e4
LT		 821 rt->u.dst.metrics[RTAX_MTU-1] = rt->u.dst.dev->mtu;
822 mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->u.dst));
823 if (rt->u.dst.metrics[RTAX_ADVMSS-1] == 0 ||
824 rt->u.dst.metrics[RTAX_ADVMSS-1] > mss)
825 rt->u.dst.metrics[RTAX_ADVMSS-1] = mss;
826 return 0;
827}
828
c4ea94ab 829static inline int dn_match_addr(__le16 addr1, __le16 addr2)
1da177e4
LT		 830{
831 __u16 tmp = dn_ntohs(addr1) ^ dn_ntohs(addr2);
832 int match = 16;
833 while(tmp) {
834 tmp >>= 1;
835 match--;
836 }
837 return match;
838}
839
c4ea94ab 840static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
1da177e4 841{
c4ea94ab 842 __le16 saddr = 0;
1da177e4
LT		 843 struct dn_dev *dn_db = dev->dn_ptr;
844 struct dn_ifaddr *ifa;
845 int best_match = 0;
846 int ret;
847
848 read_lock(&dev_base_lock);
849 for(ifa = dn_db->ifa_list; ifa; ifa = ifa->ifa_next) {
850 if (ifa->ifa_scope > scope)
851 continue;
852 if (!daddr) {
853 saddr = ifa->ifa_local;
854 break;
855 }
856 ret = dn_match_addr(daddr, ifa->ifa_local);
857 if (ret > best_match)
858 saddr = ifa->ifa_local;
859 if (best_match == 0)
860 saddr = ifa->ifa_local;
861 }
862 read_unlock(&dev_base_lock);
863
864 return saddr;
865}
866
c4ea94ab 867static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
1da177e4
LT		 868{
869 return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
870}
871
c4ea94ab 872static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
1da177e4 873{
c4ea94ab 874 __le16 mask = dnet_make_mask(res->prefixlen);
1da177e4
LT		 875 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
876}
877
878static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *oldflp, int try_hard)
879{
429eb0fa 880 struct flowi fl = { .nl_u = { .dn_u =
1da177e4
LT		 881 { .daddr = oldflp->fld_dst,
882 .saddr = oldflp->fld_src,
883 .scope = RT_SCOPE_UNIVERSE,
1da177e4 884 } },
47dcf0cb 885 .mark = oldflp->mark,
1da177e4
LT		 886 .iif = loopback_dev.ifindex,
887 .oif = oldflp->oif };
888 struct dn_route *rt = NULL;
889 struct net_device *dev_out = NULL;
890 struct neighbour *neigh = NULL;
891 unsigned hash;
892 unsigned flags = 0;
893 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
894 int err;
895 int free_res = 0;
c4ea94ab 896 __le16 gateway = 0;
1da177e4
LT		 897
898 if (decnet_debug_level & 16)
899 printk(KERN_DEBUG
900 "dn_route_output_slow: dst=%04x src=%04x mark=%d"
c4ea94ab
SW		 901 " iif=%d oif=%d\n", dn_ntohs(oldflp->fld_dst),
902 dn_ntohs(oldflp->fld_src),
429eb0fa 903 oldflp->mark, loopback_dev.ifindex, oldflp->oif);
1da177e4
LT		 904
905 /* If we have an output interface, verify its a DECnet device */
906 if (oldflp->oif) {
907 dev_out = dev_get_by_index(oldflp->oif);
908 err = -ENODEV;
909 if (dev_out && dev_out->dn_ptr == NULL) {
910 dev_put(dev_out);
911 dev_out = NULL;
912 }
913 if (dev_out == NULL)
914 goto out;
915 }
916
917 /* If we have a source address, verify that its a local address */
918 if (oldflp->fld_src) {
919 err = -EADDRNOTAVAIL;
920
921 if (dev_out) {
922 if (dn_dev_islocal(dev_out, oldflp->fld_src))
923 goto source_ok;
924 dev_put(dev_out);
925 goto out;
926 }
927 read_lock(&dev_base_lock);
928 for(dev_out = dev_base; dev_out; dev_out = dev_out->next) {
929 if (!dev_out->dn_ptr)
930 continue;
9bbf28a1
PC		 931 if (!dn_dev_islocal(dev_out, oldflp->fld_src))
932 continue;
933 if ((dev_out->flags & IFF_LOOPBACK) &&
934 oldflp->fld_dst &&
935 !dn_dev_islocal(dev_out, oldflp->fld_dst))
936 continue;
937 break;
1da177e4
LT		 938 }
939 read_unlock(&dev_base_lock);
940 if (dev_out == NULL)
941 goto out;
942 dev_hold(dev_out);
943source_ok:
944 ;
945 }
946
947 /* No destination? Assume its local */
948 if (!fl.fld_dst) {
949 fl.fld_dst = fl.fld_src;
950
951 err = -EADDRNOTAVAIL;
952 if (dev_out)
953 dev_put(dev_out);
954 dev_out = &loopback_dev;
955 dev_hold(dev_out);
956 if (!fl.fld_dst) {
957 fl.fld_dst =
958 fl.fld_src = dnet_select_source(dev_out, 0,
959 RT_SCOPE_HOST);
960 if (!fl.fld_dst)
961 goto out;
962 }
963 fl.oif = loopback_dev.ifindex;
964 res.type = RTN_LOCAL;
965 goto make_route;
966 }
967
968 if (decnet_debug_level & 16)
969 printk(KERN_DEBUG
970 "dn_route_output_slow: initial checks complete."
c4ea94ab
SW		 971 " dst=%o4x src=%04x oif=%d try_hard=%d\n",
972 dn_ntohs(fl.fld_dst), dn_ntohs(fl.fld_src),
973 fl.oif, try_hard);
1da177e4
LT		 974
975 /*
976 * N.B. If the kernel is compiled without router support then
977 * dn_fib_lookup() will evaluate to non-zero so this if () block
978 * will always be executed.
979 */
980 err = -ESRCH;
981 if (try_hard || (err = dn_fib_lookup(&fl, &res)) != 0) {
982 struct dn_dev *dn_db;
983 if (err != -ESRCH)
984 goto out;
985 /*
429eb0fa 986 * Here the fallback is basically the standard algorithm for
1da177e4
LT		 987 * routing in endnodes which is described in the DECnet routing
988 * docs
989 *
990 * If we are not trying hard, look in neighbour cache.
991 * The result is tested to ensure that if a specific output
429eb0fa 992 * device/source address was requested, then we honour that
1da177e4
LT		 993 * here
994 */
995 if (!try_hard) {
996 neigh = neigh_lookup_nodev(&dn_neigh_table, &fl.fld_dst);
997 if (neigh) {
429eb0fa 998 if ((oldflp->oif &&
1da177e4
LT		 999 (neigh->dev->ifindex != oldflp->oif)) ||
1000 (oldflp->fld_src &&
1001 (!dn_dev_islocal(neigh->dev,
1002 oldflp->fld_src)))) {
1003 neigh_release(neigh);
1004 neigh = NULL;
1005 } else {
1006 if (dev_out)
1007 dev_put(dev_out);
1008 if (dn_dev_islocal(neigh->dev, fl.fld_dst)) {
1009 dev_out = &loopback_dev;
1010 res.type = RTN_LOCAL;
1011 } else {
1012 dev_out = neigh->dev;
1013 }
1014 dev_hold(dev_out);
1015 goto select_source;
1016 }
1017 }
1018 }
1019
1020 /* Not there? Perhaps its a local address */
1021 if (dev_out == NULL)
1022 dev_out = dn_dev_get_default();
1023 err = -ENODEV;
1024 if (dev_out == NULL)
1025 goto out;
1026 dn_db = dev_out->dn_ptr;
1027 /* Possible improvement - check all devices for local addr */
1028 if (dn_dev_islocal(dev_out, fl.fld_dst)) {
1029 dev_put(dev_out);
1030 dev_out = &loopback_dev;
1031 dev_hold(dev_out);
1032 res.type = RTN_LOCAL;
1033 goto select_source;
1034 }
1035 /* Not local either.... try sending it to the default router */
1036 neigh = neigh_clone(dn_db->router);
1037 BUG_ON(neigh && neigh->dev != dev_out);
1038
1039 /* Ok then, we assume its directly connected and move on */
1040select_source:
1041 if (neigh)
1042 gateway = ((struct dn_neigh *)neigh)->addr;
1043 if (gateway == 0)
1044 gateway = fl.fld_dst;
1045 if (fl.fld_src == 0) {
1046 fl.fld_src = dnet_select_source(dev_out, gateway,
1047 res.type == RTN_LOCAL ?
429eb0fa 1048 RT_SCOPE_HOST :
1da177e4
LT		 1049 RT_SCOPE_LINK);
1050 if (fl.fld_src == 0 && res.type != RTN_LOCAL)
1051 goto e_addr;
1052 }
1053 fl.oif = dev_out->ifindex;
1054 goto make_route;
1055 }
1056 free_res = 1;
1057
1058 if (res.type == RTN_NAT)
1059 goto e_inval;
1060
1061 if (res.type == RTN_LOCAL) {
1062 if (!fl.fld_src)
1063 fl.fld_src = fl.fld_dst;
1064 if (dev_out)
1065 dev_put(dev_out);
1066 dev_out = &loopback_dev;
1067 dev_hold(dev_out);
1068 fl.oif = dev_out->ifindex;
1069 if (res.fi)
1070 dn_fib_info_put(res.fi);
1071 res.fi = NULL;
1072 goto make_route;
1073 }
1074
1075 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1076 dn_fib_select_multipath(&fl, &res);
1077
429eb0fa 1078 /*
1da177e4
LT		 1079 * We could add some logic to deal with default routes here and
1080 * get rid of some of the special casing above.
1081 */
1082
1083 if (!fl.fld_src)
1084 fl.fld_src = DN_FIB_RES_PREFSRC(res);
429eb0fa 1085
1da177e4
LT		 1086 if (dev_out)
1087 dev_put(dev_out);
1088 dev_out = DN_FIB_RES_DEV(res);
1089 dev_hold(dev_out);
1090 fl.oif = dev_out->ifindex;
1091 gateway = DN_FIB_RES_GW(res);
1092
1093make_route:
1094 if (dev_out->flags & IFF_LOOPBACK)
1095 flags |= RTCF_LOCAL;
1096
1097 rt = dst_alloc(&dn_dst_ops);
1098 if (rt == NULL)
1099 goto e_nobufs;
1100
1101 atomic_set(&rt->u.dst.__refcnt, 1);
1102 rt->u.dst.flags = DST_HOST;
1103
1104 rt->fl.fld_src = oldflp->fld_src;
1105 rt->fl.fld_dst = oldflp->fld_dst;
1106 rt->fl.oif = oldflp->oif;
1107 rt->fl.iif = 0;
47dcf0cb 1108 rt->fl.mark = oldflp->mark;
1da177e4
LT		 1109
1110 rt->rt_saddr = fl.fld_src;
1111 rt->rt_daddr = fl.fld_dst;
1112 rt->rt_gateway = gateway ? gateway : fl.fld_dst;
1113 rt->rt_local_src = fl.fld_src;
1114
1115 rt->rt_dst_map = fl.fld_dst;
1116 rt->rt_src_map = fl.fld_src;
1117
1118 rt->u.dst.dev = dev_out;
1119 dev_hold(dev_out);
1120 rt->u.dst.neighbour = neigh;
1121 neigh = NULL;
1122
1123 rt->u.dst.lastuse = jiffies;
1124 rt->u.dst.output = dn_output;
1125 rt->u.dst.input = dn_rt_bug;
1126 rt->rt_flags = flags;
1127 if (flags & RTCF_LOCAL)
1128 rt->u.dst.input = dn_nsp_rx;
1129
1130 err = dn_rt_set_next_hop(rt, &res);
1131 if (err)
1132 goto e_neighbour;
1133
1134 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1135 dn_insert_route(rt, hash, (struct dn_route **)pprt);
1136
1137done:
1138 if (neigh)
1139 neigh_release(neigh);
1140 if (free_res)
1141 dn_fib_res_put(&res);
1142 if (dev_out)
1143 dev_put(dev_out);
1144out:
1145 return err;
1146
1147e_addr:
429eb0fa
YH		 1148 err = -EADDRNOTAVAIL;
1149 goto done;
1da177e4
LT		 1150e_inval:
1151 err = -EINVAL;
1152 goto done;
1153e_nobufs:
1154 err = -ENOBUFS;
1155 goto done;
1156e_neighbour:
1157 dst_free(&rt->u.dst);
1158 goto e_nobufs;
1159}
1160
1161
1162/*
1163 * N.B. The flags may be moved into the flowi at some future stage.
1164 */
1165static int __dn_route_output_key(struct dst_entry **pprt, const struct flowi *flp, int flags)
1166{
1167 unsigned hash = dn_hash(flp->fld_src, flp->fld_dst);
1168 struct dn_route *rt = NULL;
1169
1170 if (!(flags & MSG_TRYHARD)) {
1171 rcu_read_lock_bh();
1172 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt;
0c195c3f 1173 rt = rcu_dereference(rt->u.dst.dn_next)) {
1da177e4
LT		 1174 if ((flp->fld_dst == rt->fl.fld_dst) &&
1175 (flp->fld_src == rt->fl.fld_src) &&
47dcf0cb 1176 (flp->mark == rt->fl.mark) &&
1da177e4
LT		 1177 (rt->fl.iif == 0) &&
1178 (rt->fl.oif == flp->oif)) {
1179 rt->u.dst.lastuse = jiffies;
1180 dst_hold(&rt->u.dst);
1181 rt->u.dst.__use++;
1182 rcu_read_unlock_bh();
1183 *pprt = &rt->u.dst;
1184 return 0;
1185 }
1186 }
1187 rcu_read_unlock_bh();
1188 }
1189
1190 return dn_route_output_slow(pprt, flp, flags);
1191}
1192
1193static int dn_route_output_key(struct dst_entry **pprt, struct flowi *flp, int flags)
1194{
1195 int err;
1196
1197 err = __dn_route_output_key(pprt, flp, flags);
1198 if (err == 0 && flp->proto) {
1199 err = xfrm_lookup(pprt, flp, NULL, 0);
1200 }
1201 return err;
1202}
1203
1204int dn_route_output_sock(struct dst_entry **pprt, struct flowi *fl, struct sock *sk, int flags)
1205{
1206 int err;
1207
1208 err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1209 if (err == 0 && fl->proto) {
1210 err = xfrm_lookup(pprt, fl, sk, !(flags & MSG_DONTWAIT));
1211 }
1212 return err;
1213}
1214
1215static int dn_route_input_slow(struct sk_buff *skb)
1216{
1217 struct dn_route *rt = NULL;
1218 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1219 struct net_device *in_dev = skb->dev;
1220 struct net_device *out_dev = NULL;
1221 struct dn_dev *dn_db;
1222 struct neighbour *neigh = NULL;
1223 unsigned hash;
1224 int flags = 0;
c4ea94ab
SW		 1225 __le16 gateway = 0;
1226 __le16 local_src = 0;
429eb0fa 1227 struct flowi fl = { .nl_u = { .dn_u =
1da177e4
LT		 1228 { .daddr = cb->dst,
1229 .saddr = cb->src,
1230 .scope = RT_SCOPE_UNIVERSE,
1da177e4 1231 } },
47dcf0cb 1232 .mark = skb->mark,
1da177e4
LT		 1233 .iif = skb->dev->ifindex };
1234 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1235 int err = -EINVAL;
1236 int free_res = 0;
1237
1238 dev_hold(in_dev);
1239
1240 if ((dn_db = in_dev->dn_ptr) == NULL)
1241 goto out;
1242
1243 /* Zero source addresses are not allowed */
1244 if (fl.fld_src == 0)
1245 goto out;
1246
1247 /*
1248 * In this case we've just received a packet from a source
1249 * outside ourselves pretending to come from us. We don't
1250 * allow it any further to prevent routing loops, spoofing and
1251 * other nasties. Loopback packets already have the dst attached
1252 * so this only affects packets which have originated elsewhere.
1253 */
1254 err = -ENOTUNIQ;
1255 if (dn_dev_islocal(in_dev, cb->src))
1256 goto out;
1257
1258 err = dn_fib_lookup(&fl, &res);
1259 if (err) {
1260 if (err != -ESRCH)
1261 goto out;
1262 /*
1263 * Is the destination us ?
1264 */
1265 if (!dn_dev_islocal(in_dev, cb->dst))
1266 goto e_inval;
1267
1268 res.type = RTN_LOCAL;
1da177e4 1269 } else {
c4ea94ab 1270 __le16 src_map = fl.fld_src;
1da177e4
LT		 1271 free_res = 1;
1272
1273 out_dev = DN_FIB_RES_DEV(res);
1274 if (out_dev == NULL) {
1275 if (net_ratelimit())
1276 printk(KERN_CRIT "Bug in dn_route_input_slow() "
1277 "No output device\n");
1278 goto e_inval;
1279 }
1280 dev_hold(out_dev);
1281
1282 if (res.r)
a8731cbf 1283 src_map = fl.fld_src; /* no NAT support for now */
1da177e4
LT		 1284
1285 gateway = DN_FIB_RES_GW(res);
1286 if (res.type == RTN_NAT) {
1287 fl.fld_dst = dn_fib_rules_map_destination(fl.fld_dst, &res);
1288 dn_fib_res_put(&res);
1289 free_res = 0;
1290 if (dn_fib_lookup(&fl, &res))
1291 goto e_inval;
1292 free_res = 1;
1293 if (res.type != RTN_UNICAST)
1294 goto e_inval;
1295 flags |= RTCF_DNAT;
1296 gateway = fl.fld_dst;
1297 }
1298 fl.fld_src = src_map;
1299 }
1300
1301 switch(res.type) {
1302 case RTN_UNICAST:
1303 /*
1304 * Forwarding check here, we only check for forwarding
1305 * being turned off, if you want to only forward intra
1306 * area, its up to you to set the routing tables up
1307 * correctly.
1308 */
1309 if (dn_db->parms.forwarding == 0)
1310 goto e_inval;
1311
1312 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1313 dn_fib_select_multipath(&fl, &res);
1314
429eb0fa 1315 /*
1da177e4
LT		 1316 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1317 * flag as a hint to set the intra-ethernet bit when
1318 * forwarding. If we've got NAT in operation, we don't do
1319 * this optimisation.
1320 */
1321 if (out_dev == in_dev && !(flags & RTCF_NAT))
1322 flags |= RTCF_DOREDIRECT;
1323
1324 local_src = DN_FIB_RES_PREFSRC(res);
1325
1326 case RTN_BLACKHOLE:
1327 case RTN_UNREACHABLE:
1328 break;
1329 case RTN_LOCAL:
1330 flags |= RTCF_LOCAL;
1331 fl.fld_src = cb->dst;
1332 fl.fld_dst = cb->src;
1333
1334 /* Routing tables gave us a gateway */
1335 if (gateway)
1336 goto make_route;
1337
1338 /* Packet was intra-ethernet, so we know its on-link */
3a31b9d2 1339 if (cb->rt_flags & DN_RT_F_IE) {
1da177e4
LT		 1340 gateway = cb->src;
1341 flags |= RTCF_DIRECTSRC;
1342 goto make_route;
1343 }
1344
1345 /* Use the default router if there is one */
1346 neigh = neigh_clone(dn_db->router);
1347 if (neigh) {
1348 gateway = ((struct dn_neigh *)neigh)->addr;
1349 goto make_route;
1350 }
1351
1352 /* Close eyes and pray */
1353 gateway = cb->src;
1354 flags |= RTCF_DIRECTSRC;
1355 goto make_route;
1356 default:
1357 goto e_inval;
1358 }
1359
1360make_route:
1361 rt = dst_alloc(&dn_dst_ops);
1362 if (rt == NULL)
1363 goto e_nobufs;
1364
1365 rt->rt_saddr = fl.fld_src;
1366 rt->rt_daddr = fl.fld_dst;
1367 rt->rt_gateway = fl.fld_dst;
1368 if (gateway)
1369 rt->rt_gateway = gateway;
1370 rt->rt_local_src = local_src ? local_src : rt->rt_saddr;
1371
1372 rt->rt_dst_map = fl.fld_dst;
1373 rt->rt_src_map = fl.fld_src;
1374
1375 rt->fl.fld_src = cb->src;
1376 rt->fl.fld_dst = cb->dst;
1377 rt->fl.oif = 0;
1378 rt->fl.iif = in_dev->ifindex;
47dcf0cb 1379 rt->fl.mark = fl.mark;
1da177e4
LT		 1380
1381 rt->u.dst.flags = DST_HOST;
1382 rt->u.dst.neighbour = neigh;
1383 rt->u.dst.dev = out_dev;
1384 rt->u.dst.lastuse = jiffies;
1385 rt->u.dst.output = dn_rt_bug;
1386 switch(res.type) {
1387 case RTN_UNICAST:
1388 rt->u.dst.input = dn_forward;
1389 break;
1390 case RTN_LOCAL:
1391 rt->u.dst.output = dn_output;
1392 rt->u.dst.input = dn_nsp_rx;
1393 rt->u.dst.dev = in_dev;
1394 flags |= RTCF_LOCAL;
1395 break;
1396 default:
1397 case RTN_UNREACHABLE:
1398 case RTN_BLACKHOLE:
1399 rt->u.dst.input = dn_blackhole;
1400 }
1401 rt->rt_flags = flags;
1402 if (rt->u.dst.dev)
1403 dev_hold(rt->u.dst.dev);
1404
1405 err = dn_rt_set_next_hop(rt, &res);
1406 if (err)
1407 goto e_neighbour;
1408
1409 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1410 dn_insert_route(rt, hash, (struct dn_route **)&skb->dst);
1411
1412done:
1413 if (neigh)
1414 neigh_release(neigh);
1415 if (free_res)
1416 dn_fib_res_put(&res);
1417 dev_put(in_dev);
1418 if (out_dev)
1419 dev_put(out_dev);
1420out:
1421 return err;
1422
1423e_inval:
1424 err = -EINVAL;
1425 goto done;
1426
1427e_nobufs:
1428 err = -ENOBUFS;
1429 goto done;
1430
1431e_neighbour:
1432 dst_free(&rt->u.dst);
1433 goto done;
1434}
1435
1436int dn_route_input(struct sk_buff *skb)
1437{
1438 struct dn_route *rt;
1439 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1440 unsigned hash = dn_hash(cb->src, cb->dst);
1441
1442 if (skb->dst)
1443 return 0;
1444
1445 rcu_read_lock();
1446 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
0c195c3f 1447 rt = rcu_dereference(rt->u.dst.dn_next)) {
1da177e4 1448 if ((rt->fl.fld_src == cb->src) &&
429eb0fa 1449 (rt->fl.fld_dst == cb->dst) &&
1da177e4 1450 (rt->fl.oif == 0) &&
47dcf0cb 1451 (rt->fl.mark == skb->mark) &&
1da177e4
LT		 1452 (rt->fl.iif == cb->iif)) {
1453 rt->u.dst.lastuse = jiffies;
1454 dst_hold(&rt->u.dst);
1455 rt->u.dst.__use++;
1456 rcu_read_unlock();
1457 skb->dst = (struct dst_entry *)rt;
1458 return 0;
1459 }
1460 }
1461 rcu_read_unlock();
1462
1463 return dn_route_input_slow(skb);
1464}
1465
b6544c0b
JHS		 1466static int dn_rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1467 int event, int nowait, unsigned int flags)
1da177e4
LT		 1468{
1469 struct dn_route *rt = (struct dn_route *)skb->dst;
1470 struct rtmsg *r;
1471 struct nlmsghdr *nlh;
27a884dc 1472 unsigned char *b = skb_tail_pointer(skb);
e3703b3d 1473 long expires;
1da177e4 1474
b6544c0b 1475 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
1da177e4 1476 r = NLMSG_DATA(nlh);
1da177e4
LT		 1477 r->rtm_family = AF_DECnet;
1478 r->rtm_dst_len = 16;
1479 r->rtm_src_len = 0;
1480 r->rtm_tos = 0;
1481 r->rtm_table = RT_TABLE_MAIN;
9e762a4a 1482 RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
1da177e4
LT		 1483 r->rtm_type = rt->rt_type;
1484 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1485 r->rtm_scope = RT_SCOPE_UNIVERSE;
1486 r->rtm_protocol = RTPROT_UNSPEC;
1487 if (rt->rt_flags & RTCF_NOTIFY)
1488 r->rtm_flags |= RTM_F_NOTIFY;
1489 RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr);
1490 if (rt->fl.fld_src) {
1491 r->rtm_src_len = 16;
1492 RTA_PUT(skb, RTA_SRC, 2, &rt->fl.fld_src);
1493 }
1494 if (rt->u.dst.dev)
1495 RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->u.dst.dev->ifindex);
1496 /*
1497 * Note to self - change this if input routes reverse direction when
1498 * they deal only with inputs and not with replies like they do
1499 * currently.
1500 */
1501 RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src);
1502 if (rt->rt_daddr != rt->rt_gateway)
1503 RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway);
1504 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
1505 goto rtattr_failure;
e3703b3d
TG		 1506 expires = rt->u.dst.expires ? rt->u.dst.expires - jiffies : 0;
1507 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0, expires,
1508 rt->u.dst.error) < 0)
1509 goto rtattr_failure;
1da177e4
LT		 1510 if (rt->fl.iif)
1511 RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fl.iif);
1512
27a884dc 1513 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1da177e4
LT		 1514 return skb->len;
1515
1516nlmsg_failure:
1517rtattr_failure:
dc5fc579 1518 nlmsg_trim(skb, b);
429eb0fa 1519 return -1;
1da177e4
LT		 1520}
1521
1522/*
1523 * This is called by both endnodes and routers now.
1524 */
fa34ddd7 1525static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
1da177e4
LT		 1526{
1527 struct rtattr **rta = arg;
1528 struct rtmsg *rtm = NLMSG_DATA(nlh);
1529 struct dn_route *rt = NULL;
1530 struct dn_skb_cb *cb;
1531 int err;
1532 struct sk_buff *skb;
1533 struct flowi fl;
1534
1535 memset(&fl, 0, sizeof(fl));
1536 fl.proto = DNPROTO_NSP;
1537
1538 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1539 if (skb == NULL)
1540 return -ENOBUFS;
459a98ed 1541 skb_reset_mac_header(skb);
1da177e4
LT		 1542 cb = DN_SKB_CB(skb);
1543
1544 if (rta[RTA_SRC-1])
1545 memcpy(&fl.fld_src, RTA_DATA(rta[RTA_SRC-1]), 2);
1546 if (rta[RTA_DST-1])
1547 memcpy(&fl.fld_dst, RTA_DATA(rta[RTA_DST-1]), 2);
1548 if (rta[RTA_IIF-1])
1549 memcpy(&fl.iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
1550
1551 if (fl.iif) {
1552 struct net_device *dev;
1553 if ((dev = dev_get_by_index(fl.iif)) == NULL) {
1554 kfree_skb(skb);
1555 return -ENODEV;
1556 }
1557 if (!dev->dn_ptr) {
1558 dev_put(dev);
1559 kfree_skb(skb);
1560 return -ENODEV;
1561 }
1562 skb->protocol = __constant_htons(ETH_P_DNA_RT);
1563 skb->dev = dev;
1564 cb->src = fl.fld_src;
1565 cb->dst = fl.fld_dst;
1566 local_bh_disable();
1567 err = dn_route_input(skb);
1568 local_bh_enable();
1569 memset(cb, 0, sizeof(struct dn_skb_cb));
1570 rt = (struct dn_route *)skb->dst;
1571 if (!err && -rt->u.dst.error)
1572 err = rt->u.dst.error;
1573 } else {
1574 int oif = 0;
1575 if (rta[RTA_OIF - 1])
1576 memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
1577 fl.oif = oif;
1578 err = dn_route_output_key((struct dst_entry **)&rt, &fl, 0);
1579 }
1580
1581 if (skb->dev)
1582 dev_put(skb->dev);
1583 skb->dev = NULL;
1584 if (err)
1585 goto out_free;
1586 skb->dst = &rt->u.dst;
1587 if (rtm->rtm_flags & RTM_F_NOTIFY)
1588 rt->rt_flags |= RTCF_NOTIFY;
1589
b6544c0b 1590 err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1da177e4
LT		 1591
1592 if (err == 0)
1593 goto out_free;
1594 if (err < 0) {
1595 err = -EMSGSIZE;
1596 goto out_free;
1597 }
1598
2942e900 1599 return rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
1da177e4
LT		 1600
1601out_free:
1602 kfree_skb(skb);
1603 return err;
1604}
1605
1606/*
1607 * For routers, this is called from dn_fib_dump, but for endnodes its
1608 * called directly from the rtnetlink dispatch table.
1609 */
1610int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1611{
1612 struct dn_route *rt;
1613 int h, s_h;
1614 int idx, s_idx;
1615
1616 if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg))
1617 return -EINVAL;
1618 if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED))
1619 return 0;
1620
1621 s_h = cb->args[0];
1622 s_idx = idx = cb->args[1];
1623 for(h = 0; h <= dn_rt_hash_mask; h++) {
1624 if (h < s_h)
1625 continue;
1626 if (h > s_h)
1627 s_idx = 0;
1628 rcu_read_lock_bh();
1629 for(rt = rcu_dereference(dn_rt_hash_table[h].chain), idx = 0;
1630 rt;
0c195c3f 1631 rt = rcu_dereference(rt->u.dst.dn_next), idx++) {
1da177e4
LT		 1632 if (idx < s_idx)
1633 continue;
1634 skb->dst = dst_clone(&rt->u.dst);
1635 if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
429eb0fa 1636 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
b6544c0b 1637 1, NLM_F_MULTI) <= 0) {
1da177e4
LT		 1638 dst_release(xchg(&skb->dst, NULL));
1639 rcu_read_unlock_bh();
1640 goto done;
1641 }
1642 dst_release(xchg(&skb->dst, NULL));
1643 }
1644 rcu_read_unlock_bh();
1645 }
1646
1647done:
1648 cb->args[0] = h;
1649 cb->args[1] = idx;
1650 return skb->len;
1651}
1652
1653#ifdef CONFIG_PROC_FS
1654struct dn_rt_cache_iter_state {
1655 int bucket;
1656};
1657
1658static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1659{
1660 struct dn_route *rt = NULL;
1661 struct dn_rt_cache_iter_state *s = seq->private;
1662
1663 for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1664 rcu_read_lock_bh();
1665 rt = dn_rt_hash_table[s->bucket].chain;
1666 if (rt)
1667 break;
1668 rcu_read_unlock_bh();
1669 }
1670 return rt;
1671}
1672
1673static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1674{
1675 struct dn_rt_cache_iter_state *s = rcu_dereference(seq->private);
1676
0c195c3f 1677 rt = rt->u.dst.dn_next;
1da177e4
LT		 1678 while(!rt) {
1679 rcu_read_unlock_bh();
1680 if (--s->bucket < 0)
1681 break;
1682 rcu_read_lock_bh();
1683 rt = dn_rt_hash_table[s->bucket].chain;
1684 }
1685 return rt;
1686}
1687
1688static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1689{
1690 struct dn_route *rt = dn_rt_cache_get_first(seq);
1691
1692 if (rt) {
1693 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1694 --*pos;
1695 }
1696 return *pos ? NULL : rt;
1697}
1698
1699static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1700{
1701 struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1702 ++*pos;
1703 return rt;
1704}
1705
1706static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1707{
1708 if (v)
1709 rcu_read_unlock_bh();
1710}
1711
1712static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1713{
1714 struct dn_route *rt = v;
1715 char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1716
1717 seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1718 rt->u.dst.dev ? rt->u.dst.dev->name : "*",
1719 dn_addr2asc(dn_ntohs(rt->rt_daddr), buf1),
1720 dn_addr2asc(dn_ntohs(rt->rt_saddr), buf2),
1721 atomic_read(&rt->u.dst.__refcnt),
1722 rt->u.dst.__use,
1723 (int) dst_metric(&rt->u.dst, RTAX_RTT));
1724 return 0;
429eb0fa 1725}
1da177e4
LT		 1726
1727static struct seq_operations dn_rt_cache_seq_ops = {
1728 .start = dn_rt_cache_seq_start,
1729 .next = dn_rt_cache_seq_next,
1730 .stop = dn_rt_cache_seq_stop,
1731 .show = dn_rt_cache_seq_show,
1732};
1733
1734static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1735{
1736 struct seq_file *seq;
1737 int rc = -ENOMEM;
1738 struct dn_rt_cache_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
1739
1740 if (!s)
1741 goto out;
1742 rc = seq_open(file, &dn_rt_cache_seq_ops);
1743 if (rc)
1744 goto out_kfree;
1745 seq = file->private_data;
1746 seq->private = s;
1747 memset(s, 0, sizeof(*s));
1748out:
1749 return rc;
1750out_kfree:
1751 kfree(s);
1752 goto out;
1753}
1754
9a32144e 1755static const struct file_operations dn_rt_cache_seq_fops = {
1da177e4
LT		 1756 .owner = THIS_MODULE,
1757 .open = dn_rt_cache_seq_open,
1758 .read = seq_read,
1759 .llseek = seq_lseek,
1760 .release = seq_release_private,
1761};
1762
1763#endif /* CONFIG_PROC_FS */
1764
1765void __init dn_route_init(void)
1766{
1767 int i, goal, order;
1768
e5d679f3
AD		 1769 dn_dst_ops.kmem_cachep =
1770 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1771 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
1da177e4
LT		 1772 init_timer(&dn_route_timer);
1773 dn_route_timer.function = dn_dst_check_expire;
1774 dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1775 add_timer(&dn_route_timer);
1776
1777 goal = num_physpages >> (26 - PAGE_SHIFT);
1778
1779 for(order = 0; (1UL << order) < goal; order++)
1780 /* NOTHING */;
1781
429eb0fa
YH		 1782 /*
1783 * Only want 1024 entries max, since the table is very, very unlikely
1784 * to be larger than that.
1785 */
1786 while(order && ((((1UL << order) * PAGE_SIZE) /
1787 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1788 order--;
1789
1790 do {
1791 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1792 sizeof(struct dn_rt_hash_bucket);
1793 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1794 dn_rt_hash_mask--;
1795 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1796 __get_free_pages(GFP_ATOMIC, order);
1797 } while (dn_rt_hash_table == NULL && --order > 0);
1da177e4
LT		 1798
1799 if (!dn_rt_hash_table)
429eb0fa 1800 panic("Failed to allocate DECnet route cache hash table\n");
1da177e4 1801
429eb0fa
YH		 1802 printk(KERN_INFO
1803 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1804 dn_rt_hash_mask,
1da177e4
LT		 1805 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1806
1807 dn_rt_hash_mask--;
429eb0fa
YH		 1808 for(i = 0; i <= dn_rt_hash_mask; i++) {
1809 spin_lock_init(&dn_rt_hash_table[i].lock);
1810 dn_rt_hash_table[i].chain = NULL;
1811 }
1da177e4 1812
429eb0fa 1813 dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1da177e4
LT		 1814
1815 proc_net_fops_create("decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
fa34ddd7
TG		 1816
1817#ifdef CONFIG_DECNET_ROUTER
1818 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute, dn_fib_dump);
1819#else
1820 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1821 dn_cache_dump);
1822#endif
1da177e4
LT		 1823}
1824
1825void __exit dn_route_cleanup(void)
1826{
1827 del_timer(&dn_route_timer);
1828 dn_run_flush(0);
1829
1830 proc_net_remove("decnet_cache");
1831}
1832
Clone of davem's net-next-2.6 tree