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allow coexistance of N build and AC build.
[tomato.git] / release / src-rt-6.x / linux / linux-2.6 / net / decnet / dn_route.c
blobb6f61a3ad32cf5a79b70f8b21268ea345be4a758
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 <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>
80 #include <net/netlink.h>
81 #include <net/neighbour.h>
82 #include <net/dst.h>
83 #include <net/flow.h>
84 #include <net/fib_rules.h>
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
92 struct dn_rt_hash_bucket
93 {
94 struct dn_route *chain;
95 spinlock_t lock;
96 } __attribute__((__aligned__(8)));
97
98 extern struct neigh_table dn_neigh_table;
99
100
101 static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
102
103 static const int dn_rt_min_delay = 2 * HZ;
104 static const int dn_rt_max_delay = 10 * HZ;
105 static const int dn_rt_mtu_expires = 10 * 60 * HZ;
106
107 static unsigned long dn_rt_deadline;
108
109 static int dn_dst_gc(void);
110 static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
111 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
112 static void dn_dst_link_failure(struct sk_buff *);
113 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
114 static int dn_route_input(struct sk_buff *);
115 static void dn_run_flush(unsigned long dummy);
116
117 static struct dn_rt_hash_bucket *dn_rt_hash_table;
118 static unsigned dn_rt_hash_mask;
119
120 static struct timer_list dn_route_timer;
121 static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
122 int decnet_dst_gc_interval = 2;
123
124 static 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
137 static __inline__ unsigned dn_hash(__le16 src, __le16 dst)
138 {
139 __u16 tmp = (__u16 __force)(src ^ dst);
140 tmp ^= (tmp >> 3);
141 tmp ^= (tmp >> 5);
142 tmp ^= (tmp >> 10);
143 return dn_rt_hash_mask & (unsigned)tmp;
144 }
145
146 static inline void dnrt_free(struct dn_route *rt)
147 {
148 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
149 }
150
151 static inline void dnrt_drop(struct dn_route *rt)
152 {
153 dst_release(&rt->u.dst);
154 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
155 }
156
157 static 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) {
171 rtp = &rt->u.dst.dn_next;
172 continue;
173 }
174 *rtp = rt->u.dst.dn_next;
175 rt->u.dst.dn_next = NULL;
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
187 static 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) {
202 rtp = &rt->u.dst.dn_next;
203 continue;
204 }
205 *rtp = rt->u.dst.dn_next;
206 rt->u.dst.dn_next = NULL;
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 */
226 static 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
250 /*
251 * When a route has been marked obsolete. (e.g. routing cache flush)
252 */
253 static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
254 {
255 return NULL;
256 }
257
258 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
259 {
260 dst_release(dst);
261 return NULL;
262 }
263
264 static void dn_dst_link_failure(struct sk_buff *skb)
265 {
266 return;
267 }
268
269 static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
270 {
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) |
273 (fl1->mark ^ fl2->mark) |
274 (fl1->nl_u.dn_u.scope ^ fl2->nl_u.dn_u.scope) |
275 (fl1->oif ^ fl2->oif) |
276 (fl1->iif ^ fl2->iif)) == 0;
277 }
278
279 static 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 */
290 *rthp = rth->u.dst.dn_next;
291 rcu_assign_pointer(rth->u.dst.dn_next,
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 }
304 rthp = &rth->u.dst.dn_next;
305 }
306
307 rcu_assign_pointer(rt->u.dst.dn_next, dn_rt_hash_table[hash].chain);
308 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
309
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
318 void 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) {
330 next = rt->u.dst.dn_next;
331 rt->u.dst.dn_next = NULL;
332 dst_free((struct dst_entry *)rt);
333 }
334
335 nothing_to_declare:
336 spin_unlock_bh(&dn_rt_hash_table[i].lock);
337 }
338 }
339
340 static DEFINE_SPINLOCK(dn_rt_flush_lock);
341
342 void 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 */
381 static int dn_return_short(struct sk_buff *skb)
382 {
383 struct dn_skb_cb *cb;
384 unsigned char *ptr;
385 __le16 *src;
386 __le16 *dst;
387 __le16 tmp;
388
389 /* Add back headers */
390 skb_push(skb, skb->data - skb_network_header(skb));
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
400 dst = (__le16 *)ptr;
401 ptr += 2;
402 src = (__le16 *)ptr;
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 */
421 static 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 */
429 skb_push(skb, skb->data - skb_network_header(skb));
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 */
468 static 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",
481 (int)cb->rt_flags, devname, skb->len,
482 dn_ntohs(cb->src), dn_ntohs(cb->dst),
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
499 static 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);
508 skb_reset_transport_header(skb);
509
510 /* Destination info */
511 ptr += 2;
512 cb->dst = dn_eth2dn(ptr);
513 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
514 goto drop_it;
515 ptr += 6;
516
517
518 /* Source info */
519 ptr += 2;
520 cb->src = dn_eth2dn(ptr);
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 */
527
528 return NF_HOOK(PF_DECnet, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet);
529
530 drop_it:
531 kfree_skb(skb);
532 return NET_RX_DROP;
533 }
534
535
536
537 static 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);
546 skb_reset_transport_header(skb);
547
548 cb->dst = *(__le16 *)ptr;
549 ptr += 2;
550 cb->src = *(__le16 *)ptr;
551 ptr += 2;
552 cb->hops = *ptr & 0x3f;
553
554 return NF_HOOK(PF_DECnet, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet);
555
556 drop_it:
557 kfree_skb(skb);
558 return NET_RX_DROP;
559 }
560
561 static 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
571 static 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
578 int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
579 {
580 struct dn_skb_cb *cb;
581 unsigned char flags = 0;
582 __u16 len = dn_ntohs(*(__le16 *)skb->data);
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
619 skb_reset_network_header(skb);
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)
630 printk(KERN_DEBUG
631 "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
632 (int)flags, (dev) ? dev->name : "???", len, skb->len,
633 padlen);
634
635 if (flags & DN_RT_PKT_CNTL) {
636 if (unlikely(skb_linearize(skb)))
637 goto dump_it;
638
639 switch(flags & DN_RT_CNTL_MSK) {
640 case DN_RT_PKT_INIT:
641 dn_dev_init_pkt(skb);
642 break;
643 case DN_RT_PKT_VERI:
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) {
652 case DN_RT_PKT_HELO:
653 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_route_ptp_hello);
654
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:
659 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_router_hello);
660
661 case DN_RT_PKT_EEDH:
662 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_endnode_hello);
663 }
664 } else {
665 if (dn->parms.state != DN_DEV_S_RU)
666 goto dump_it;
667
668 skb_pull(skb, 1); /* Pull flags */
669
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);
675 }
676 }
677
678 dump_it:
679 kfree_skb(skb);
680 out:
681 return NET_RX_DROP;
682 }
683
684 static 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
713 error:
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
722 static 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
762 drop:
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 */
772 static 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 */
782 static 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",
788 dn_ntohs(cb->src), dn_ntohs(cb->dst));
789 }
790
791 kfree_skb(skb);
792
793 return NET_RX_BAD;
794 }
795
796 static 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
819 if (rt->u.dst.metrics[RTAX_MTU-1] == 0 ||
820 rt->u.dst.metrics[RTAX_MTU-1] > rt->u.dst.dev->mtu)
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
829 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
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
840 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
841 {
842 __le16 saddr = 0;
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
867 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
868 {
869 return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
870 }
871
872 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
873 {
874 __le16 mask = dnet_make_mask(res->prefixlen);
875 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
876 }
877
878 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *oldflp, int try_hard)
879 {
880 struct flowi fl = { .nl_u = { .dn_u =
881 { .daddr = oldflp->fld_dst,
882 .saddr = oldflp->fld_src,
883 .scope = RT_SCOPE_UNIVERSE,
884 } },
885 .mark = oldflp->mark,
886 .iif = loopback_dev.ifindex,
887 .oif = oldflp->oif };
888 struct dn_route *rt = NULL;
889 struct net_device *dev_out = NULL, *dev;
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;
896 __le16 gateway = 0;
897
898 if (decnet_debug_level & 16)
899 printk(KERN_DEBUG
900 "dn_route_output_slow: dst=%04x src=%04x mark=%d"
901 " iif=%d oif=%d\n", dn_ntohs(oldflp->fld_dst),
902 dn_ntohs(oldflp->fld_src),
903 oldflp->mark, loopback_dev.ifindex, oldflp->oif);
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_each_netdev(dev) {
929 if (!dev->dn_ptr)
930 continue;
931 if (!dn_dev_islocal(dev, oldflp->fld_src))
932 continue;
933 if ((dev->flags & IFF_LOOPBACK) &&
934 oldflp->fld_dst &&
935 !dn_dev_islocal(dev, oldflp->fld_dst))
936 continue;
937
938 dev_out = dev;
939 break;
940 }
941 read_unlock(&dev_base_lock);
942 if (dev_out == NULL)
943 goto out;
944 dev_hold(dev_out);
945 source_ok:
946 ;
947 }
948
949 /* No destination? Assume its local */
950 if (!fl.fld_dst) {
951 fl.fld_dst = fl.fld_src;
952
953 err = -EADDRNOTAVAIL;
954 if (dev_out)
955 dev_put(dev_out);
956 dev_out = &loopback_dev;
957 dev_hold(dev_out);
958 if (!fl.fld_dst) {
959 fl.fld_dst =
960 fl.fld_src = dnet_select_source(dev_out, 0,
961 RT_SCOPE_HOST);
962 if (!fl.fld_dst)
963 goto out;
964 }
965 fl.oif = loopback_dev.ifindex;
966 res.type = RTN_LOCAL;
967 goto make_route;
968 }
969
970 if (decnet_debug_level & 16)
971 printk(KERN_DEBUG
972 "dn_route_output_slow: initial checks complete."
973 " dst=%o4x src=%04x oif=%d try_hard=%d\n",
974 dn_ntohs(fl.fld_dst), dn_ntohs(fl.fld_src),
975 fl.oif, try_hard);
976
977 /*
978 * N.B. If the kernel is compiled without router support then
979 * dn_fib_lookup() will evaluate to non-zero so this if () block
980 * will always be executed.
981 */
982 err = -ESRCH;
983 if (try_hard || (err = dn_fib_lookup(&fl, &res)) != 0) {
984 struct dn_dev *dn_db;
985 if (err != -ESRCH)
986 goto out;
987 /*
988 * Here the fallback is basically the standard algorithm for
989 * routing in endnodes which is described in the DECnet routing
990 * docs
991 *
992 * If we are not trying hard, look in neighbour cache.
993 * The result is tested to ensure that if a specific output
994 * device/source address was requested, then we honour that
995 * here
996 */
997 if (!try_hard) {
998 neigh = neigh_lookup_nodev(&dn_neigh_table, &fl.fld_dst);
999 if (neigh) {
1000 if ((oldflp->oif &&
1001 (neigh->dev->ifindex != oldflp->oif)) ||
1002 (oldflp->fld_src &&
1003 (!dn_dev_islocal(neigh->dev,
1004 oldflp->fld_src)))) {
1005 neigh_release(neigh);
1006 neigh = NULL;
1007 } else {
1008 if (dev_out)
1009 dev_put(dev_out);
1010 if (dn_dev_islocal(neigh->dev, fl.fld_dst)) {
1011 dev_out = &loopback_dev;
1012 res.type = RTN_LOCAL;
1013 } else {
1014 dev_out = neigh->dev;
1015 }
1016 dev_hold(dev_out);
1017 goto select_source;
1018 }
1019 }
1020 }
1021
1022 /* Not there? Perhaps its a local address */
1023 if (dev_out == NULL)
1024 dev_out = dn_dev_get_default();
1025 err = -ENODEV;
1026 if (dev_out == NULL)
1027 goto out;
1028 dn_db = dev_out->dn_ptr;
1029 /* Possible improvement - check all devices for local addr */
1030 if (dn_dev_islocal(dev_out, fl.fld_dst)) {
1031 dev_put(dev_out);
1032 dev_out = &loopback_dev;
1033 dev_hold(dev_out);
1034 res.type = RTN_LOCAL;
1035 goto select_source;
1036 }
1037 /* Not local either.... try sending it to the default router */
1038 neigh = neigh_clone(dn_db->router);
1039 BUG_ON(neigh && neigh->dev != dev_out);
1040
1041 /* Ok then, we assume its directly connected and move on */
1042 select_source:
1043 if (neigh)
1044 gateway = ((struct dn_neigh *)neigh)->addr;
1045 if (gateway == 0)
1046 gateway = fl.fld_dst;
1047 if (fl.fld_src == 0) {
1048 fl.fld_src = dnet_select_source(dev_out, gateway,
1049 res.type == RTN_LOCAL ?
1050 RT_SCOPE_HOST :
1051 RT_SCOPE_LINK);
1052 if (fl.fld_src == 0 && res.type != RTN_LOCAL)
1053 goto e_addr;
1054 }
1055 fl.oif = dev_out->ifindex;
1056 goto make_route;
1057 }
1058 free_res = 1;
1059
1060 if (res.type == RTN_NAT)
1061 goto e_inval;
1062
1063 if (res.type == RTN_LOCAL) {
1064 if (!fl.fld_src)
1065 fl.fld_src = fl.fld_dst;
1066 if (dev_out)
1067 dev_put(dev_out);
1068 dev_out = &loopback_dev;
1069 dev_hold(dev_out);
1070 fl.oif = dev_out->ifindex;
1071 if (res.fi)
1072 dn_fib_info_put(res.fi);
1073 res.fi = NULL;
1074 goto make_route;
1075 }
1076
1077 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1078 dn_fib_select_multipath(&fl, &res);
1079
1080 /*
1081 * We could add some logic to deal with default routes here and
1082 * get rid of some of the special casing above.
1083 */
1084
1085 if (!fl.fld_src)
1086 fl.fld_src = DN_FIB_RES_PREFSRC(res);
1087
1088 if (dev_out)
1089 dev_put(dev_out);
1090 dev_out = DN_FIB_RES_DEV(res);
1091 dev_hold(dev_out);
1092 fl.oif = dev_out->ifindex;
1093 gateway = DN_FIB_RES_GW(res);
1094
1095 make_route:
1096 if (dev_out->flags & IFF_LOOPBACK)
1097 flags |= RTCF_LOCAL;
1098
1099 rt = dst_alloc(&dn_dst_ops);
1100 if (rt == NULL)
1101 goto e_nobufs;
1102
1103 atomic_set(&rt->u.dst.__refcnt, 1);
1104 rt->u.dst.flags = DST_HOST;
1105
1106 rt->fl.fld_src = oldflp->fld_src;
1107 rt->fl.fld_dst = oldflp->fld_dst;
1108 rt->fl.oif = oldflp->oif;
1109 rt->fl.iif = 0;
1110 rt->fl.mark = oldflp->mark;
1111
1112 rt->rt_saddr = fl.fld_src;
1113 rt->rt_daddr = fl.fld_dst;
1114 rt->rt_gateway = gateway ? gateway : fl.fld_dst;
1115 rt->rt_local_src = fl.fld_src;
1116
1117 rt->rt_dst_map = fl.fld_dst;
1118 rt->rt_src_map = fl.fld_src;
1119
1120 rt->u.dst.dev = dev_out;
1121 dev_hold(dev_out);
1122 rt->u.dst.neighbour = neigh;
1123 neigh = NULL;
1124
1125 rt->u.dst.lastuse = jiffies;
1126 rt->u.dst.output = dn_output;
1127 rt->u.dst.input = dn_rt_bug;
1128 rt->rt_flags = flags;
1129 if (flags & RTCF_LOCAL)
1130 rt->u.dst.input = dn_nsp_rx;
1131
1132 err = dn_rt_set_next_hop(rt, &res);
1133 if (err)
1134 goto e_neighbour;
1135
1136 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1137 dn_insert_route(rt, hash, (struct dn_route **)pprt);
1138
1139 done:
1140 if (neigh)
1141 neigh_release(neigh);
1142 if (free_res)
1143 dn_fib_res_put(&res);
1144 if (dev_out)
1145 dev_put(dev_out);
1146 out:
1147 return err;
1148
1149 e_addr:
1150 err = -EADDRNOTAVAIL;
1151 goto done;
1152 e_inval:
1153 err = -EINVAL;
1154 goto done;
1155 e_nobufs:
1156 err = -ENOBUFS;
1157 goto done;
1158 e_neighbour:
1159 dst_free(&rt->u.dst);
1160 goto e_nobufs;
1161 }
1162
1163
1164 /*
1165 * N.B. The flags may be moved into the flowi at some future stage.
1166 */
1167 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowi *flp, int flags)
1168 {
1169 unsigned hash = dn_hash(flp->fld_src, flp->fld_dst);
1170 struct dn_route *rt = NULL;
1171
1172 if (!(flags & MSG_TRYHARD)) {
1173 rcu_read_lock_bh();
1174 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt;
1175 rt = rcu_dereference(rt->u.dst.dn_next)) {
1176 if ((flp->fld_dst == rt->fl.fld_dst) &&
1177 (flp->fld_src == rt->fl.fld_src) &&
1178 (flp->mark == rt->fl.mark) &&
1179 (rt->fl.iif == 0) &&
1180 (rt->fl.oif == flp->oif)) {
1181 rt->u.dst.lastuse = jiffies;
1182 dst_hold(&rt->u.dst);
1183 rt->u.dst.__use++;
1184 rcu_read_unlock_bh();
1185 *pprt = &rt->u.dst;
1186 return 0;
1187 }
1188 }
1189 rcu_read_unlock_bh();
1190 }
1191
1192 return dn_route_output_slow(pprt, flp, flags);
1193 }
1194
1195 static int dn_route_output_key(struct dst_entry **pprt, struct flowi *flp, int flags)
1196 {
1197 int err;
1198
1199 err = __dn_route_output_key(pprt, flp, flags);
1200 if (err == 0 && flp->proto) {
1201 err = xfrm_lookup(pprt, flp, NULL, 0);
1202 }
1203 return err;
1204 }
1205
1206 int dn_route_output_sock(struct dst_entry **pprt, struct flowi *fl, struct sock *sk, int flags)
1207 {
1208 int err;
1209
1210 err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1211 if (err == 0 && fl->proto) {
1212 err = xfrm_lookup(pprt, fl, sk, !(flags & MSG_DONTWAIT));
1213 }
1214 return err;
1215 }
1216
1217 static int dn_route_input_slow(struct sk_buff *skb)
1218 {
1219 struct dn_route *rt = NULL;
1220 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1221 struct net_device *in_dev = skb->dev;
1222 struct net_device *out_dev = NULL;
1223 struct dn_dev *dn_db;
1224 struct neighbour *neigh = NULL;
1225 unsigned hash;
1226 int flags = 0;
1227 __le16 gateway = 0;
1228 __le16 local_src = 0;
1229 struct flowi fl = { .nl_u = { .dn_u =
1230 { .daddr = cb->dst,
1231 .saddr = cb->src,
1232 .scope = RT_SCOPE_UNIVERSE,
1233 } },
1234 .mark = skb->mark,
1235 .iif = skb->dev->ifindex };
1236 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1237 int err = -EINVAL;
1238 int free_res = 0;
1239
1240 dev_hold(in_dev);
1241
1242 if ((dn_db = in_dev->dn_ptr) == NULL)
1243 goto out;
1244
1245 /* Zero source addresses are not allowed */
1246 if (fl.fld_src == 0)
1247 goto out;
1248
1249 /*
1250 * In this case we've just received a packet from a source
1251 * outside ourselves pretending to come from us. We don't
1252 * allow it any further to prevent routing loops, spoofing and
1253 * other nasties. Loopback packets already have the dst attached
1254 * so this only affects packets which have originated elsewhere.
1255 */
1256 err = -ENOTUNIQ;
1257 if (dn_dev_islocal(in_dev, cb->src))
1258 goto out;
1259
1260 err = dn_fib_lookup(&fl, &res);
1261 if (err) {
1262 if (err != -ESRCH)
1263 goto out;
1264 /*
1265 * Is the destination us ?
1266 */
1267 if (!dn_dev_islocal(in_dev, cb->dst))
1268 goto e_inval;
1269
1270 res.type = RTN_LOCAL;
1271 } else {
1272 __le16 src_map = fl.fld_src;
1273 free_res = 1;
1274
1275 out_dev = DN_FIB_RES_DEV(res);
1276 if (out_dev == NULL) {
1277 if (net_ratelimit())
1278 printk(KERN_CRIT "Bug in dn_route_input_slow() "
1279 "No output device\n");
1280 goto e_inval;
1281 }
1282 dev_hold(out_dev);
1283
1284 if (res.r)
1285 src_map = fl.fld_src; /* no NAT support for now */
1286
1287 gateway = DN_FIB_RES_GW(res);
1288 if (res.type == RTN_NAT) {
1289 fl.fld_dst = dn_fib_rules_map_destination(fl.fld_dst, &res);
1290 dn_fib_res_put(&res);
1291 free_res = 0;
1292 if (dn_fib_lookup(&fl, &res))
1293 goto e_inval;
1294 free_res = 1;
1295 if (res.type != RTN_UNICAST)
1296 goto e_inval;
1297 flags |= RTCF_DNAT;
1298 gateway = fl.fld_dst;
1299 }
1300 fl.fld_src = src_map;
1301 }
1302
1303 switch(res.type) {
1304 case RTN_UNICAST:
1305 /*
1306 * Forwarding check here, we only check for forwarding
1307 * being turned off, if you want to only forward intra
1308 * area, its up to you to set the routing tables up
1309 * correctly.
1310 */
1311 if (dn_db->parms.forwarding == 0)
1312 goto e_inval;
1313
1314 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1315 dn_fib_select_multipath(&fl, &res);
1316
1317 /*
1318 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1319 * flag as a hint to set the intra-ethernet bit when
1320 * forwarding. If we've got NAT in operation, we don't do
1321 * this optimisation.
1322 */
1323 if (out_dev == in_dev && !(flags & RTCF_NAT))
1324 flags |= RTCF_DOREDIRECT;
1325
1326 local_src = DN_FIB_RES_PREFSRC(res);
1327
1328 case RTN_BLACKHOLE:
1329 case RTN_UNREACHABLE:
1330 break;
1331 case RTN_LOCAL:
1332 flags |= RTCF_LOCAL;
1333 fl.fld_src = cb->dst;
1334 fl.fld_dst = cb->src;
1335
1336 /* Routing tables gave us a gateway */
1337 if (gateway)
1338 goto make_route;
1339
1340 /* Packet was intra-ethernet, so we know its on-link */
1341 if (cb->rt_flags & DN_RT_F_IE) {
1342 gateway = cb->src;
1343 flags |= RTCF_DIRECTSRC;
1344 goto make_route;
1345 }
1346
1347 /* Use the default router if there is one */
1348 neigh = neigh_clone(dn_db->router);
1349 if (neigh) {
1350 gateway = ((struct dn_neigh *)neigh)->addr;
1351 goto make_route;
1352 }
1353
1354 /* Close eyes and pray */
1355 gateway = cb->src;
1356 flags |= RTCF_DIRECTSRC;
1357 goto make_route;
1358 default:
1359 goto e_inval;
1360 }
1361
1362 make_route:
1363 rt = dst_alloc(&dn_dst_ops);
1364 if (rt == NULL)
1365 goto e_nobufs;
1366
1367 rt->rt_saddr = fl.fld_src;
1368 rt->rt_daddr = fl.fld_dst;
1369 rt->rt_gateway = fl.fld_dst;
1370 if (gateway)
1371 rt->rt_gateway = gateway;
1372 rt->rt_local_src = local_src ? local_src : rt->rt_saddr;
1373
1374 rt->rt_dst_map = fl.fld_dst;
1375 rt->rt_src_map = fl.fld_src;
1376
1377 rt->fl.fld_src = cb->src;
1378 rt->fl.fld_dst = cb->dst;
1379 rt->fl.oif = 0;
1380 rt->fl.iif = in_dev->ifindex;
1381 rt->fl.mark = fl.mark;
1382
1383 rt->u.dst.flags = DST_HOST;
1384 rt->u.dst.neighbour = neigh;
1385 rt->u.dst.dev = out_dev;
1386 rt->u.dst.lastuse = jiffies;
1387 rt->u.dst.output = dn_rt_bug;
1388 switch(res.type) {
1389 case RTN_UNICAST:
1390 rt->u.dst.input = dn_forward;
1391 break;
1392 case RTN_LOCAL:
1393 rt->u.dst.output = dn_output;
1394 rt->u.dst.input = dn_nsp_rx;
1395 rt->u.dst.dev = in_dev;
1396 flags |= RTCF_LOCAL;
1397 break;
1398 default:
1399 case RTN_UNREACHABLE:
1400 case RTN_BLACKHOLE:
1401 rt->u.dst.input = dn_blackhole;
1402 }
1403 rt->rt_flags = flags;
1404 if (rt->u.dst.dev)
1405 dev_hold(rt->u.dst.dev);
1406
1407 err = dn_rt_set_next_hop(rt, &res);
1408 if (err)
1409 goto e_neighbour;
1410
1411 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1412 dn_insert_route(rt, hash, (struct dn_route **)&skb->dst);
1413
1414 done:
1415 if (neigh)
1416 neigh_release(neigh);
1417 if (free_res)
1418 dn_fib_res_put(&res);
1419 dev_put(in_dev);
1420 if (out_dev)
1421 dev_put(out_dev);
1422 out:
1423 return err;
1424
1425 e_inval:
1426 err = -EINVAL;
1427 goto done;
1428
1429 e_nobufs:
1430 err = -ENOBUFS;
1431 goto done;
1432
1433 e_neighbour:
1434 dst_free(&rt->u.dst);
1435 goto done;
1436 }
1437
1438 int dn_route_input(struct sk_buff *skb)
1439 {
1440 struct dn_route *rt;
1441 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1442 unsigned hash = dn_hash(cb->src, cb->dst);
1443
1444 if (skb->dst)
1445 return 0;
1446
1447 rcu_read_lock();
1448 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1449 rt = rcu_dereference(rt->u.dst.dn_next)) {
1450 if ((rt->fl.fld_src == cb->src) &&
1451 (rt->fl.fld_dst == cb->dst) &&
1452 (rt->fl.oif == 0) &&
1453 (rt->fl.mark == skb->mark) &&
1454 (rt->fl.iif == cb->iif)) {
1455 rt->u.dst.lastuse = jiffies;
1456 dst_hold(&rt->u.dst);
1457 rt->u.dst.__use++;
1458 rcu_read_unlock();
1459 skb->dst = (struct dst_entry *)rt;
1460 return 0;
1461 }
1462 }
1463 rcu_read_unlock();
1464
1465 return dn_route_input_slow(skb);
1466 }
1467
1468 static int dn_rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1469 int event, int nowait, unsigned int flags)
1470 {
1471 struct dn_route *rt = (struct dn_route *)skb->dst;
1472 struct rtmsg *r;
1473 struct nlmsghdr *nlh;
1474 unsigned char *b = skb_tail_pointer(skb);
1475 long expires;
1476
1477 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
1478 r = NLMSG_DATA(nlh);
1479 r->rtm_family = AF_DECnet;
1480 r->rtm_dst_len = 16;
1481 r->rtm_src_len = 0;
1482 r->rtm_tos = 0;
1483 r->rtm_table = RT_TABLE_MAIN;
1484 RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
1485 r->rtm_type = rt->rt_type;
1486 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1487 r->rtm_scope = RT_SCOPE_UNIVERSE;
1488 r->rtm_protocol = RTPROT_UNSPEC;
1489 if (rt->rt_flags & RTCF_NOTIFY)
1490 r->rtm_flags |= RTM_F_NOTIFY;
1491 RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr);
1492 if (rt->fl.fld_src) {
1493 r->rtm_src_len = 16;
1494 RTA_PUT(skb, RTA_SRC, 2, &rt->fl.fld_src);
1495 }
1496 if (rt->u.dst.dev)
1497 RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->u.dst.dev->ifindex);
1498 /*
1499 * Note to self - change this if input routes reverse direction when
1500 * they deal only with inputs and not with replies like they do
1501 * currently.
1502 */
1503 RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src);
1504 if (rt->rt_daddr != rt->rt_gateway)
1505 RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway);
1506 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
1507 goto rtattr_failure;
1508 expires = rt->u.dst.expires ? rt->u.dst.expires - jiffies : 0;
1509 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0, expires,
1510 rt->u.dst.error) < 0)
1511 goto rtattr_failure;
1512 if (rt->fl.iif)
1513 RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fl.iif);
1514
1515 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1516 return skb->len;
1517
1518 nlmsg_failure:
1519 rtattr_failure:
1520 nlmsg_trim(skb, b);
1521 return -1;
1522 }
1523
1524 /*
1525 * This is called by both endnodes and routers now.
1526 */
1527 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
1528 {
1529 struct rtattr **rta = arg;
1530 struct rtmsg *rtm = NLMSG_DATA(nlh);
1531 struct dn_route *rt = NULL;
1532 struct dn_skb_cb *cb;
1533 int err;
1534 struct sk_buff *skb;
1535 struct flowi fl;
1536
1537 memset(&fl, 0, sizeof(fl));
1538 fl.proto = DNPROTO_NSP;
1539
1540 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1541 if (skb == NULL)
1542 return -ENOBUFS;
1543 skb_reset_mac_header(skb);
1544 cb = DN_SKB_CB(skb);
1545
1546 if (rta[RTA_SRC-1])
1547 memcpy(&fl.fld_src, RTA_DATA(rta[RTA_SRC-1]), 2);
1548 if (rta[RTA_DST-1])
1549 memcpy(&fl.fld_dst, RTA_DATA(rta[RTA_DST-1]), 2);
1550 if (rta[RTA_IIF-1])
1551 memcpy(&fl.iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
1552
1553 if (fl.iif) {
1554 struct net_device *dev;
1555 if ((dev = dev_get_by_index(fl.iif)) == NULL) {
1556 kfree_skb(skb);
1557 return -ENODEV;
1558 }
1559 if (!dev->dn_ptr) {
1560 dev_put(dev);
1561 kfree_skb(skb);
1562 return -ENODEV;
1563 }
1564 skb->protocol = __constant_htons(ETH_P_DNA_RT);
1565 skb->dev = dev;
1566 cb->src = fl.fld_src;
1567 cb->dst = fl.fld_dst;
1568 local_bh_disable();
1569 err = dn_route_input(skb);
1570 local_bh_enable();
1571 memset(cb, 0, sizeof(struct dn_skb_cb));
1572 rt = (struct dn_route *)skb->dst;
1573 if (!err && -rt->u.dst.error)
1574 err = rt->u.dst.error;
1575 } else {
1576 int oif = 0;
1577 if (rta[RTA_OIF - 1])
1578 memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
1579 fl.oif = oif;
1580 err = dn_route_output_key((struct dst_entry **)&rt, &fl, 0);
1581 }
1582
1583 if (skb->dev)
1584 dev_put(skb->dev);
1585 skb->dev = NULL;
1586 if (err)
1587 goto out_free;
1588 skb->dst = &rt->u.dst;
1589 if (rtm->rtm_flags & RTM_F_NOTIFY)
1590 rt->rt_flags |= RTCF_NOTIFY;
1591
1592 err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1593
1594 if (err == 0)
1595 goto out_free;
1596 if (err < 0) {
1597 err = -EMSGSIZE;
1598 goto out_free;
1599 }
1600
1601 return rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
1602
1603 out_free:
1604 kfree_skb(skb);
1605 return err;
1606 }
1607
1608 /*
1609 * For routers, this is called from dn_fib_dump, but for endnodes its
1610 * called directly from the rtnetlink dispatch table.
1611 */
1612 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1613 {
1614 struct dn_route *rt;
1615 int h, s_h;
1616 int idx, s_idx;
1617
1618 if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg))
1619 return -EINVAL;
1620 if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED))
1621 return 0;
1622
1623 s_h = cb->args[0];
1624 s_idx = idx = cb->args[1];
1625 for(h = 0; h <= dn_rt_hash_mask; h++) {
1626 if (h < s_h)
1627 continue;
1628 if (h > s_h)
1629 s_idx = 0;
1630 rcu_read_lock_bh();
1631 for(rt = rcu_dereference(dn_rt_hash_table[h].chain), idx = 0;
1632 rt;
1633 rt = rcu_dereference(rt->u.dst.dn_next), idx++) {
1634 if (idx < s_idx)
1635 continue;
1636 skb->dst = dst_clone(&rt->u.dst);
1637 if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
1638 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1639 1, NLM_F_MULTI) <= 0) {
1640 dst_release(xchg(&skb->dst, NULL));
1641 rcu_read_unlock_bh();
1642 goto done;
1643 }
1644 dst_release(xchg(&skb->dst, NULL));
1645 }
1646 rcu_read_unlock_bh();
1647 }
1648
1649 done:
1650 cb->args[0] = h;
1651 cb->args[1] = idx;
1652 return skb->len;
1653 }
1654
1655 #ifdef CONFIG_PROC_FS
1656 struct dn_rt_cache_iter_state {
1657 int bucket;
1658 };
1659
1660 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1661 {
1662 struct dn_route *rt = NULL;
1663 struct dn_rt_cache_iter_state *s = seq->private;
1664
1665 for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1666 rcu_read_lock_bh();
1667 rt = dn_rt_hash_table[s->bucket].chain;
1668 if (rt)
1669 break;
1670 rcu_read_unlock_bh();
1671 }
1672 return rt;
1673 }
1674
1675 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1676 {
1677 struct dn_rt_cache_iter_state *s = rcu_dereference(seq->private);
1678
1679 rt = rt->u.dst.dn_next;
1680 while(!rt) {
1681 rcu_read_unlock_bh();
1682 if (--s->bucket < 0)
1683 break;
1684 rcu_read_lock_bh();
1685 rt = dn_rt_hash_table[s->bucket].chain;
1686 }
1687 return rt;
1688 }
1689
1690 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1691 {
1692 struct dn_route *rt = dn_rt_cache_get_first(seq);
1693
1694 if (rt) {
1695 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1696 --*pos;
1697 }
1698 return *pos ? NULL : rt;
1699 }
1700
1701 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1702 {
1703 struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1704 ++*pos;
1705 return rt;
1706 }
1707
1708 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1709 {
1710 if (v)
1711 rcu_read_unlock_bh();
1712 }
1713
1714 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1715 {
1716 struct dn_route *rt = v;
1717 char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1718
1719 seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1720 rt->u.dst.dev ? rt->u.dst.dev->name : "*",
1721 dn_addr2asc(dn_ntohs(rt->rt_daddr), buf1),
1722 dn_addr2asc(dn_ntohs(rt->rt_saddr), buf2),
1723 atomic_read(&rt->u.dst.__refcnt),
1724 rt->u.dst.__use,
1725 (int) dst_metric(&rt->u.dst, RTAX_RTT));
1726 return 0;
1727 }
1728
1729 static struct seq_operations dn_rt_cache_seq_ops = {
1730 .start = dn_rt_cache_seq_start,
1731 .next = dn_rt_cache_seq_next,
1732 .stop = dn_rt_cache_seq_stop,
1733 .show = dn_rt_cache_seq_show,
1734 };
1735
1736 static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1737 {
1738 return seq_open_private(file, &dn_rt_cache_seq_ops,
1739 sizeof(struct dn_rt_cache_iter_state));
1740 }
1741
1742 static const struct file_operations dn_rt_cache_seq_fops = {
1743 .owner = THIS_MODULE,
1744 .open = dn_rt_cache_seq_open,
1745 .read = seq_read,
1746 .llseek = seq_lseek,
1747 .release = seq_release_private,
1748 };
1749
1750 #endif /* CONFIG_PROC_FS */
1751
1752 void __init dn_route_init(void)
1753 {
1754 int i, goal, order;
1755
1756 dn_dst_ops.kmem_cachep =
1757 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1758 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
1759 init_timer(&dn_route_timer);
1760 dn_route_timer.function = dn_dst_check_expire;
1761 dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1762 add_timer(&dn_route_timer);
1763
1764 goal = num_physpages >> (26 - PAGE_SHIFT);
1765
1766 for(order = 0; (1UL << order) < goal; order++)
1767 /* NOTHING */;
1768
1769 /*
1770 * Only want 1024 entries max, since the table is very, very unlikely
1771 * to be larger than that.
1772 */
1773 while(order && ((((1UL << order) * PAGE_SIZE) /
1774 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1775 order--;
1776
1777 do {
1778 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1779 sizeof(struct dn_rt_hash_bucket);
1780 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1781 dn_rt_hash_mask--;
1782 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1783 __get_free_pages(GFP_ATOMIC, order);
1784 } while (dn_rt_hash_table == NULL && --order > 0);
1785
1786 if (!dn_rt_hash_table)
1787 panic("Failed to allocate DECnet route cache hash table\n");
1788
1789 printk(KERN_INFO
1790 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1791 dn_rt_hash_mask,
1792 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1793
1794 dn_rt_hash_mask--;
1795 for(i = 0; i <= dn_rt_hash_mask; i++) {
1796 spin_lock_init(&dn_rt_hash_table[i].lock);
1797 dn_rt_hash_table[i].chain = NULL;
1798 }
1799
1800 dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1801
1802 proc_net_fops_create("decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
1803
1804 #ifdef CONFIG_DECNET_ROUTER
1805 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute, dn_fib_dump);
1806 #else
1807 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1808 dn_cache_dump);
1809 #endif
1810 }
1811
1812 void __exit dn_route_cleanup(void)
1813 {
1814 del_timer(&dn_route_timer);
1815 dn_run_flush(0);
1816
1817 proc_net_remove("decnet_cache");
1818 }
1819
Tomato firmware and modifications.