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sysfs: Rewrite rename in terms of sysfs dirents
[linux-2.6/kmemtrace.git] / net / decnet / dn_route.c
blob97eee5e8fbbe35c1ec63ff45d8cb2dedd6aeba73
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/net_namespace.h>
81 #include <net/netlink.h>
82 #include <net/neighbour.h>
83 #include <net/dst.h>
84 #include <net/flow.h>
85 #include <net/fib_rules.h>
86 #include <net/dn.h>
87 #include <net/dn_dev.h>
88 #include <net/dn_nsp.h>
89 #include <net/dn_route.h>
90 #include <net/dn_neigh.h>
91 #include <net/dn_fib.h>
92
93 struct dn_rt_hash_bucket
94 {
95 struct dn_route *chain;
96 spinlock_t lock;
97 } __attribute__((__aligned__(8)));
98
99 extern struct neigh_table dn_neigh_table;
100
101
102 static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
103
104 static const int dn_rt_min_delay = 2 * HZ;
105 static const int dn_rt_max_delay = 10 * HZ;
106 static const int dn_rt_mtu_expires = 10 * 60 * HZ;
107
108 static unsigned long dn_rt_deadline;
109
110 static int dn_dst_gc(void);
111 static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
112 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
113 static void dn_dst_link_failure(struct sk_buff *);
114 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
115 static int dn_route_input(struct sk_buff *);
116 static void dn_run_flush(unsigned long dummy);
117
118 static struct dn_rt_hash_bucket *dn_rt_hash_table;
119 static unsigned dn_rt_hash_mask;
120
121 static struct timer_list dn_route_timer;
122 static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
123 int decnet_dst_gc_interval = 2;
124
125 static struct dst_ops dn_dst_ops = {
126 .family = PF_DECnet,
127 .protocol = __constant_htons(ETH_P_DNA_RT),
128 .gc_thresh = 128,
129 .gc = dn_dst_gc,
130 .check = dn_dst_check,
131 .negative_advice = dn_dst_negative_advice,
132 .link_failure = dn_dst_link_failure,
133 .update_pmtu = dn_dst_update_pmtu,
134 .entry_size = sizeof(struct dn_route),
135 .entries = ATOMIC_INIT(0),
136 };
137
138 static __inline__ unsigned dn_hash(__le16 src, __le16 dst)
139 {
140 __u16 tmp = (__u16 __force)(src ^ dst);
141 tmp ^= (tmp >> 3);
142 tmp ^= (tmp >> 5);
143 tmp ^= (tmp >> 10);
144 return dn_rt_hash_mask & (unsigned)tmp;
145 }
146
147 static inline void dnrt_free(struct dn_route *rt)
148 {
149 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
150 }
151
152 static inline void dnrt_drop(struct dn_route *rt)
153 {
154 dst_release(&rt->u.dst);
155 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
156 }
157
158 static void dn_dst_check_expire(unsigned long dummy)
159 {
160 int i;
161 struct dn_route *rt, **rtp;
162 unsigned long now = jiffies;
163 unsigned long expire = 120 * HZ;
164
165 for(i = 0; i <= dn_rt_hash_mask; i++) {
166 rtp = &dn_rt_hash_table[i].chain;
167
168 spin_lock(&dn_rt_hash_table[i].lock);
169 while((rt=*rtp) != NULL) {
170 if (atomic_read(&rt->u.dst.__refcnt) ||
171 (now - rt->u.dst.lastuse) < expire) {
172 rtp = &rt->u.dst.dn_next;
173 continue;
174 }
175 *rtp = rt->u.dst.dn_next;
176 rt->u.dst.dn_next = NULL;
177 dnrt_free(rt);
178 }
179 spin_unlock(&dn_rt_hash_table[i].lock);
180
181 if ((jiffies - now) > 0)
182 break;
183 }
184
185 mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ);
186 }
187
188 static int dn_dst_gc(void)
189 {
190 struct dn_route *rt, **rtp;
191 int i;
192 unsigned long now = jiffies;
193 unsigned long expire = 10 * HZ;
194
195 for(i = 0; i <= dn_rt_hash_mask; i++) {
196
197 spin_lock_bh(&dn_rt_hash_table[i].lock);
198 rtp = &dn_rt_hash_table[i].chain;
199
200 while((rt=*rtp) != NULL) {
201 if (atomic_read(&rt->u.dst.__refcnt) ||
202 (now - rt->u.dst.lastuse) < expire) {
203 rtp = &rt->u.dst.dn_next;
204 continue;
205 }
206 *rtp = rt->u.dst.dn_next;
207 rt->u.dst.dn_next = NULL;
208 dnrt_drop(rt);
209 break;
210 }
211 spin_unlock_bh(&dn_rt_hash_table[i].lock);
212 }
213
214 return 0;
215 }
216
217 /*
218 * The decnet standards don't impose a particular minimum mtu, what they
219 * do insist on is that the routing layer accepts a datagram of at least
220 * 230 bytes long. Here we have to subtract the routing header length from
221 * 230 to get the minimum acceptable mtu. If there is no neighbour, then we
222 * assume the worst and use a long header size.
223 *
224 * We update both the mtu and the advertised mss (i.e. the segment size we
225 * advertise to the other end).
226 */
227 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu)
228 {
229 u32 min_mtu = 230;
230 struct dn_dev *dn = dst->neighbour ?
231 (struct dn_dev *)dst->neighbour->dev->dn_ptr : NULL;
232
233 if (dn && dn->use_long == 0)
234 min_mtu -= 6;
235 else
236 min_mtu -= 21;
237
238 if (dst->metrics[RTAX_MTU-1] > mtu && mtu >= min_mtu) {
239 if (!(dst_metric_locked(dst, RTAX_MTU))) {
240 dst->metrics[RTAX_MTU-1] = mtu;
241 dst_set_expires(dst, dn_rt_mtu_expires);
242 }
243 if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
244 u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
245 if (dst->metrics[RTAX_ADVMSS-1] > mss)
246 dst->metrics[RTAX_ADVMSS-1] = mss;
247 }
248 }
249 }
250
251 /*
252 * When a route has been marked obsolete. (e.g. routing cache flush)
253 */
254 static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
255 {
256 return NULL;
257 }
258
259 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
260 {
261 dst_release(dst);
262 return NULL;
263 }
264
265 static void dn_dst_link_failure(struct sk_buff *skb)
266 {
267 return;
268 }
269
270 static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
271 {
272 return ((fl1->nl_u.dn_u.daddr ^ fl2->nl_u.dn_u.daddr) |
273 (fl1->nl_u.dn_u.saddr ^ fl2->nl_u.dn_u.saddr) |
274 (fl1->mark ^ fl2->mark) |
275 (fl1->nl_u.dn_u.scope ^ fl2->nl_u.dn_u.scope) |
276 (fl1->oif ^ fl2->oif) |
277 (fl1->iif ^ fl2->iif)) == 0;
278 }
279
280 static int dn_insert_route(struct dn_route *rt, unsigned hash, struct dn_route **rp)
281 {
282 struct dn_route *rth, **rthp;
283 unsigned long now = jiffies;
284
285 rthp = &dn_rt_hash_table[hash].chain;
286
287 spin_lock_bh(&dn_rt_hash_table[hash].lock);
288 while((rth = *rthp) != NULL) {
289 if (compare_keys(&rth->fl, &rt->fl)) {
290 /* Put it first */
291 *rthp = rth->u.dst.dn_next;
292 rcu_assign_pointer(rth->u.dst.dn_next,
293 dn_rt_hash_table[hash].chain);
294 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
295
296 rth->u.dst.__use++;
297 dst_hold(&rth->u.dst);
298 rth->u.dst.lastuse = now;
299 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
300
301 dnrt_drop(rt);
302 *rp = rth;
303 return 0;
304 }
305 rthp = &rth->u.dst.dn_next;
306 }
307
308 rcu_assign_pointer(rt->u.dst.dn_next, dn_rt_hash_table[hash].chain);
309 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
310
311 dst_hold(&rt->u.dst);
312 rt->u.dst.__use++;
313 rt->u.dst.lastuse = now;
314 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
315 *rp = rt;
316 return 0;
317 }
318
319 void dn_run_flush(unsigned long dummy)
320 {
321 int i;
322 struct dn_route *rt, *next;
323
324 for(i = 0; i < dn_rt_hash_mask; i++) {
325 spin_lock_bh(&dn_rt_hash_table[i].lock);
326
327 if ((rt = xchg(&dn_rt_hash_table[i].chain, NULL)) == NULL)
328 goto nothing_to_declare;
329
330 for(; rt; rt=next) {
331 next = rt->u.dst.dn_next;
332 rt->u.dst.dn_next = NULL;
333 dst_free((struct dst_entry *)rt);
334 }
335
336 nothing_to_declare:
337 spin_unlock_bh(&dn_rt_hash_table[i].lock);
338 }
339 }
340
341 static DEFINE_SPINLOCK(dn_rt_flush_lock);
342
343 void dn_rt_cache_flush(int delay)
344 {
345 unsigned long now = jiffies;
346 int user_mode = !in_interrupt();
347
348 if (delay < 0)
349 delay = dn_rt_min_delay;
350
351 spin_lock_bh(&dn_rt_flush_lock);
352
353 if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
354 long tmo = (long)(dn_rt_deadline - now);
355
356 if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
357 tmo = 0;
358
359 if (delay > tmo)
360 delay = tmo;
361 }
362
363 if (delay <= 0) {
364 spin_unlock_bh(&dn_rt_flush_lock);
365 dn_run_flush(0);
366 return;
367 }
368
369 if (dn_rt_deadline == 0)
370 dn_rt_deadline = now + dn_rt_max_delay;
371
372 dn_rt_flush_timer.expires = now + delay;
373 add_timer(&dn_rt_flush_timer);
374 spin_unlock_bh(&dn_rt_flush_lock);
375 }
376
377 /**
378 * dn_return_short - Return a short packet to its sender
379 * @skb: The packet to return
380 *
381 */
382 static int dn_return_short(struct sk_buff *skb)
383 {
384 struct dn_skb_cb *cb;
385 unsigned char *ptr;
386 __le16 *src;
387 __le16 *dst;
388 __le16 tmp;
389
390 /* Add back headers */
391 skb_push(skb, skb->data - skb_network_header(skb));
392
393 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
394 return NET_RX_DROP;
395
396 cb = DN_SKB_CB(skb);
397 /* Skip packet length and point to flags */
398 ptr = skb->data + 2;
399 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
400
401 dst = (__le16 *)ptr;
402 ptr += 2;
403 src = (__le16 *)ptr;
404 ptr += 2;
405 *ptr = 0; /* Zero hop count */
406
407 /* Swap source and destination */
408 tmp = *src;
409 *src = *dst;
410 *dst = tmp;
411
412 skb->pkt_type = PACKET_OUTGOING;
413 dn_rt_finish_output(skb, NULL, NULL);
414 return NET_RX_SUCCESS;
415 }
416
417 /**
418 * dn_return_long - Return a long packet to its sender
419 * @skb: The long format packet to return
420 *
421 */
422 static int dn_return_long(struct sk_buff *skb)
423 {
424 struct dn_skb_cb *cb;
425 unsigned char *ptr;
426 unsigned char *src_addr, *dst_addr;
427 unsigned char tmp[ETH_ALEN];
428
429 /* Add back all headers */
430 skb_push(skb, skb->data - skb_network_header(skb));
431
432 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
433 return NET_RX_DROP;
434
435 cb = DN_SKB_CB(skb);
436 /* Ignore packet length and point to flags */
437 ptr = skb->data + 2;
438
439 /* Skip padding */
440 if (*ptr & DN_RT_F_PF) {
441 char padlen = (*ptr & ~DN_RT_F_PF);
442 ptr += padlen;
443 }
444
445 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
446 ptr += 2;
447 dst_addr = ptr;
448 ptr += 8;
449 src_addr = ptr;
450 ptr += 6;
451 *ptr = 0; /* Zero hop count */
452
453 /* Swap source and destination */
454 memcpy(tmp, src_addr, ETH_ALEN);
455 memcpy(src_addr, dst_addr, ETH_ALEN);
456 memcpy(dst_addr, tmp, ETH_ALEN);
457
458 skb->pkt_type = PACKET_OUTGOING;
459 dn_rt_finish_output(skb, dst_addr, src_addr);
460 return NET_RX_SUCCESS;
461 }
462
463 /**
464 * dn_route_rx_packet - Try and find a route for an incoming packet
465 * @skb: The packet to find a route for
466 *
467 * Returns: result of input function if route is found, error code otherwise
468 */
469 static int dn_route_rx_packet(struct sk_buff *skb)
470 {
471 struct dn_skb_cb *cb = DN_SKB_CB(skb);
472 int err;
473
474 if ((err = dn_route_input(skb)) == 0)
475 return dst_input(skb);
476
477 if (decnet_debug_level & 4) {
478 char *devname = skb->dev ? skb->dev->name : "???";
479 struct dn_skb_cb *cb = DN_SKB_CB(skb);
480 printk(KERN_DEBUG
481 "DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
482 (int)cb->rt_flags, devname, skb->len,
483 dn_ntohs(cb->src), dn_ntohs(cb->dst),
484 err, skb->pkt_type);
485 }
486
487 if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
488 switch(cb->rt_flags & DN_RT_PKT_MSK) {
489 case DN_RT_PKT_SHORT:
490 return dn_return_short(skb);
491 case DN_RT_PKT_LONG:
492 return dn_return_long(skb);
493 }
494 }
495
496 kfree_skb(skb);
497 return NET_RX_DROP;
498 }
499
500 static int dn_route_rx_long(struct sk_buff *skb)
501 {
502 struct dn_skb_cb *cb = DN_SKB_CB(skb);
503 unsigned char *ptr = skb->data;
504
505 if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
506 goto drop_it;
507
508 skb_pull(skb, 20);
509 skb_reset_transport_header(skb);
510
511 /* Destination info */
512 ptr += 2;
513 cb->dst = dn_eth2dn(ptr);
514 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
515 goto drop_it;
516 ptr += 6;
517
518
519 /* Source info */
520 ptr += 2;
521 cb->src = dn_eth2dn(ptr);
522 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
523 goto drop_it;
524 ptr += 6;
525 /* Other junk */
526 ptr++;
527 cb->hops = *ptr++; /* Visit Count */
528
529 return NF_HOOK(PF_DECnet, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet);
530
531 drop_it:
532 kfree_skb(skb);
533 return NET_RX_DROP;
534 }
535
536
537
538 static int dn_route_rx_short(struct sk_buff *skb)
539 {
540 struct dn_skb_cb *cb = DN_SKB_CB(skb);
541 unsigned char *ptr = skb->data;
542
543 if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
544 goto drop_it;
545
546 skb_pull(skb, 5);
547 skb_reset_transport_header(skb);
548
549 cb->dst = *(__le16 *)ptr;
550 ptr += 2;
551 cb->src = *(__le16 *)ptr;
552 ptr += 2;
553 cb->hops = *ptr & 0x3f;
554
555 return NF_HOOK(PF_DECnet, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet);
556
557 drop_it:
558 kfree_skb(skb);
559 return NET_RX_DROP;
560 }
561
562 static int dn_route_discard(struct sk_buff *skb)
563 {
564 /*
565 * I know we drop the packet here, but thats considered success in
566 * this case
567 */
568 kfree_skb(skb);
569 return NET_RX_SUCCESS;
570 }
571
572 static int dn_route_ptp_hello(struct sk_buff *skb)
573 {
574 dn_dev_hello(skb);
575 dn_neigh_pointopoint_hello(skb);
576 return NET_RX_SUCCESS;
577 }
578
579 int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
580 {
581 struct dn_skb_cb *cb;
582 unsigned char flags = 0;
583 __u16 len = dn_ntohs(*(__le16 *)skb->data);
584 struct dn_dev *dn = (struct dn_dev *)dev->dn_ptr;
585 unsigned char padlen = 0;
586
587 if (dev->nd_net != &init_net)
588 goto dump_it;
589
590 if (dn == NULL)
591 goto dump_it;
592
593 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
594 goto out;
595
596 if (!pskb_may_pull(skb, 3))
597 goto dump_it;
598
599 skb_pull(skb, 2);
600
601 if (len > skb->len)
602 goto dump_it;
603
604 skb_trim(skb, len);
605
606 flags = *skb->data;
607
608 cb = DN_SKB_CB(skb);
609 cb->stamp = jiffies;
610 cb->iif = dev->ifindex;
611
612 /*
613 * If we have padding, remove it.
614 */
615 if (flags & DN_RT_F_PF) {
616 padlen = flags & ~DN_RT_F_PF;
617 if (!pskb_may_pull(skb, padlen + 1))
618 goto dump_it;
619 skb_pull(skb, padlen);
620 flags = *skb->data;
621 }
622
623 skb_reset_network_header(skb);
624
625 /*
626 * Weed out future version DECnet
627 */
628 if (flags & DN_RT_F_VER)
629 goto dump_it;
630
631 cb->rt_flags = flags;
632
633 if (decnet_debug_level & 1)
634 printk(KERN_DEBUG
635 "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
636 (int)flags, (dev) ? dev->name : "???", len, skb->len,
637 padlen);
638
639 if (flags & DN_RT_PKT_CNTL) {
640 if (unlikely(skb_linearize(skb)))
641 goto dump_it;
642
643 switch(flags & DN_RT_CNTL_MSK) {
644 case DN_RT_PKT_INIT:
645 dn_dev_init_pkt(skb);
646 break;
647 case DN_RT_PKT_VERI:
648 dn_dev_veri_pkt(skb);
649 break;
650 }
651
652 if (dn->parms.state != DN_DEV_S_RU)
653 goto dump_it;
654
655 switch(flags & DN_RT_CNTL_MSK) {
656 case DN_RT_PKT_HELO:
657 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_route_ptp_hello);
658
659 case DN_RT_PKT_L1RT:
660 case DN_RT_PKT_L2RT:
661 return NF_HOOK(PF_DECnet, NF_DN_ROUTE, skb, skb->dev, NULL, dn_route_discard);
662 case DN_RT_PKT_ERTH:
663 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_router_hello);
664
665 case DN_RT_PKT_EEDH:
666 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_endnode_hello);
667 }
668 } else {
669 if (dn->parms.state != DN_DEV_S_RU)
670 goto dump_it;
671
672 skb_pull(skb, 1); /* Pull flags */
673
674 switch(flags & DN_RT_PKT_MSK) {
675 case DN_RT_PKT_LONG:
676 return dn_route_rx_long(skb);
677 case DN_RT_PKT_SHORT:
678 return dn_route_rx_short(skb);
679 }
680 }
681
682 dump_it:
683 kfree_skb(skb);
684 out:
685 return NET_RX_DROP;
686 }
687
688 static int dn_output(struct sk_buff *skb)
689 {
690 struct dst_entry *dst = skb->dst;
691 struct dn_route *rt = (struct dn_route *)dst;
692 struct net_device *dev = dst->dev;
693 struct dn_skb_cb *cb = DN_SKB_CB(skb);
694 struct neighbour *neigh;
695
696 int err = -EINVAL;
697
698 if ((neigh = dst->neighbour) == NULL)
699 goto error;
700
701 skb->dev = dev;
702
703 cb->src = rt->rt_saddr;
704 cb->dst = rt->rt_daddr;
705
706 /*
707 * Always set the Intra-Ethernet bit on all outgoing packets
708 * originated on this node. Only valid flag from upper layers
709 * is return-to-sender-requested. Set hop count to 0 too.
710 */
711 cb->rt_flags &= ~DN_RT_F_RQR;
712 cb->rt_flags |= DN_RT_F_IE;
713 cb->hops = 0;
714
715 return NF_HOOK(PF_DECnet, NF_DN_LOCAL_OUT, skb, NULL, dev, neigh->output);
716
717 error:
718 if (net_ratelimit())
719 printk(KERN_DEBUG "dn_output: This should not happen\n");
720
721 kfree_skb(skb);
722
723 return err;
724 }
725
726 static int dn_forward(struct sk_buff *skb)
727 {
728 struct dn_skb_cb *cb = DN_SKB_CB(skb);
729 struct dst_entry *dst = skb->dst;
730 struct dn_dev *dn_db = dst->dev->dn_ptr;
731 struct dn_route *rt;
732 struct neighbour *neigh = dst->neighbour;
733 int header_len;
734 #ifdef CONFIG_NETFILTER
735 struct net_device *dev = skb->dev;
736 #endif
737
738 if (skb->pkt_type != PACKET_HOST)
739 goto drop;
740
741 /* Ensure that we have enough space for headers */
742 rt = (struct dn_route *)skb->dst;
743 header_len = dn_db->use_long ? 21 : 6;
744 if (skb_cow(skb, LL_RESERVED_SPACE(rt->u.dst.dev)+header_len))
745 goto drop;
746
747 /*
748 * Hop count exceeded.
749 */
750 if (++cb->hops > 30)
751 goto drop;
752
753 skb->dev = rt->u.dst.dev;
754
755 /*
756 * If packet goes out same interface it came in on, then set
757 * the Intra-Ethernet bit. This has no effect for short
758 * packets, so we don't need to test for them here.
759 */
760 cb->rt_flags &= ~DN_RT_F_IE;
761 if (rt->rt_flags & RTCF_DOREDIRECT)
762 cb->rt_flags |= DN_RT_F_IE;
763
764 return NF_HOOK(PF_DECnet, NF_DN_FORWARD, skb, dev, skb->dev, neigh->output);
765
766 drop:
767 kfree_skb(skb);
768 return NET_RX_DROP;
769 }
770
771 /*
772 * Drop packet. This is used for endnodes and for
773 * when we should not be forwarding packets from
774 * this dest.
775 */
776 static int dn_blackhole(struct sk_buff *skb)
777 {
778 kfree_skb(skb);
779 return NET_RX_DROP;
780 }
781
782 /*
783 * Used to catch bugs. This should never normally get
784 * called.
785 */
786 static int dn_rt_bug(struct sk_buff *skb)
787 {
788 if (net_ratelimit()) {
789 struct dn_skb_cb *cb = DN_SKB_CB(skb);
790
791 printk(KERN_DEBUG "dn_rt_bug: skb from:%04x to:%04x\n",
792 dn_ntohs(cb->src), dn_ntohs(cb->dst));
793 }
794
795 kfree_skb(skb);
796
797 return NET_RX_BAD;
798 }
799
800 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
801 {
802 struct dn_fib_info *fi = res->fi;
803 struct net_device *dev = rt->u.dst.dev;
804 struct neighbour *n;
805 unsigned mss;
806
807 if (fi) {
808 if (DN_FIB_RES_GW(*res) &&
809 DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
810 rt->rt_gateway = DN_FIB_RES_GW(*res);
811 memcpy(rt->u.dst.metrics, fi->fib_metrics,
812 sizeof(rt->u.dst.metrics));
813 }
814 rt->rt_type = res->type;
815
816 if (dev != NULL && rt->u.dst.neighbour == NULL) {
817 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
818 if (IS_ERR(n))
819 return PTR_ERR(n);
820 rt->u.dst.neighbour = n;
821 }
822
823 if (rt->u.dst.metrics[RTAX_MTU-1] == 0 ||
824 rt->u.dst.metrics[RTAX_MTU-1] > rt->u.dst.dev->mtu)
825 rt->u.dst.metrics[RTAX_MTU-1] = rt->u.dst.dev->mtu;
826 mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->u.dst));
827 if (rt->u.dst.metrics[RTAX_ADVMSS-1] == 0 ||
828 rt->u.dst.metrics[RTAX_ADVMSS-1] > mss)
829 rt->u.dst.metrics[RTAX_ADVMSS-1] = mss;
830 return 0;
831 }
832
833 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
834 {
835 __u16 tmp = dn_ntohs(addr1) ^ dn_ntohs(addr2);
836 int match = 16;
837 while(tmp) {
838 tmp >>= 1;
839 match--;
840 }
841 return match;
842 }
843
844 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
845 {
846 __le16 saddr = 0;
847 struct dn_dev *dn_db = dev->dn_ptr;
848 struct dn_ifaddr *ifa;
849 int best_match = 0;
850 int ret;
851
852 read_lock(&dev_base_lock);
853 for(ifa = dn_db->ifa_list; ifa; ifa = ifa->ifa_next) {
854 if (ifa->ifa_scope > scope)
855 continue;
856 if (!daddr) {
857 saddr = ifa->ifa_local;
858 break;
859 }
860 ret = dn_match_addr(daddr, ifa->ifa_local);
861 if (ret > best_match)
862 saddr = ifa->ifa_local;
863 if (best_match == 0)
864 saddr = ifa->ifa_local;
865 }
866 read_unlock(&dev_base_lock);
867
868 return saddr;
869 }
870
871 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
872 {
873 return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
874 }
875
876 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
877 {
878 __le16 mask = dnet_make_mask(res->prefixlen);
879 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
880 }
881
882 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *oldflp, int try_hard)
883 {
884 struct flowi fl = { .nl_u = { .dn_u =
885 { .daddr = oldflp->fld_dst,
886 .saddr = oldflp->fld_src,
887 .scope = RT_SCOPE_UNIVERSE,
888 } },
889 .mark = oldflp->mark,
890 .iif = init_net.loopback_dev->ifindex,
891 .oif = oldflp->oif };
892 struct dn_route *rt = NULL;
893 struct net_device *dev_out = NULL, *dev;
894 struct neighbour *neigh = NULL;
895 unsigned hash;
896 unsigned flags = 0;
897 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
898 int err;
899 int free_res = 0;
900 __le16 gateway = 0;
901
902 if (decnet_debug_level & 16)
903 printk(KERN_DEBUG
904 "dn_route_output_slow: dst=%04x src=%04x mark=%d"
905 " iif=%d oif=%d\n", dn_ntohs(oldflp->fld_dst),
906 dn_ntohs(oldflp->fld_src),
907 oldflp->mark, init_net.loopback_dev->ifindex, oldflp->oif);
908
909 /* If we have an output interface, verify its a DECnet device */
910 if (oldflp->oif) {
911 dev_out = dev_get_by_index(&init_net, oldflp->oif);
912 err = -ENODEV;
913 if (dev_out && dev_out->dn_ptr == NULL) {
914 dev_put(dev_out);
915 dev_out = NULL;
916 }
917 if (dev_out == NULL)
918 goto out;
919 }
920
921 /* If we have a source address, verify that its a local address */
922 if (oldflp->fld_src) {
923 err = -EADDRNOTAVAIL;
924
925 if (dev_out) {
926 if (dn_dev_islocal(dev_out, oldflp->fld_src))
927 goto source_ok;
928 dev_put(dev_out);
929 goto out;
930 }
931 read_lock(&dev_base_lock);
932 for_each_netdev(&init_net, dev) {
933 if (!dev->dn_ptr)
934 continue;
935 if (!dn_dev_islocal(dev, oldflp->fld_src))
936 continue;
937 if ((dev->flags & IFF_LOOPBACK) &&
938 oldflp->fld_dst &&
939 !dn_dev_islocal(dev, oldflp->fld_dst))
940 continue;
941
942 dev_out = dev;
943 break;
944 }
945 read_unlock(&dev_base_lock);
946 if (dev_out == NULL)
947 goto out;
948 dev_hold(dev_out);
949 source_ok:
950 ;
951 }
952
953 /* No destination? Assume its local */
954 if (!fl.fld_dst) {
955 fl.fld_dst = fl.fld_src;
956
957 err = -EADDRNOTAVAIL;
958 if (dev_out)
959 dev_put(dev_out);
960 dev_out = init_net.loopback_dev;
961 dev_hold(dev_out);
962 if (!fl.fld_dst) {
963 fl.fld_dst =
964 fl.fld_src = dnet_select_source(dev_out, 0,
965 RT_SCOPE_HOST);
966 if (!fl.fld_dst)
967 goto out;
968 }
969 fl.oif = init_net.loopback_dev->ifindex;
970 res.type = RTN_LOCAL;
971 goto make_route;
972 }
973
974 if (decnet_debug_level & 16)
975 printk(KERN_DEBUG
976 "dn_route_output_slow: initial checks complete."
977 " dst=%o4x src=%04x oif=%d try_hard=%d\n",
978 dn_ntohs(fl.fld_dst), dn_ntohs(fl.fld_src),
979 fl.oif, try_hard);
980
981 /*
982 * N.B. If the kernel is compiled without router support then
983 * dn_fib_lookup() will evaluate to non-zero so this if () block
984 * will always be executed.
985 */
986 err = -ESRCH;
987 if (try_hard || (err = dn_fib_lookup(&fl, &res)) != 0) {
988 struct dn_dev *dn_db;
989 if (err != -ESRCH)
990 goto out;
991 /*
992 * Here the fallback is basically the standard algorithm for
993 * routing in endnodes which is described in the DECnet routing
994 * docs
995 *
996 * If we are not trying hard, look in neighbour cache.
997 * The result is tested to ensure that if a specific output
998 * device/source address was requested, then we honour that
999 * here
1000 */
1001 if (!try_hard) {
1002 neigh = neigh_lookup_nodev(&dn_neigh_table, &fl.fld_dst);
1003 if (neigh) {
1004 if ((oldflp->oif &&
1005 (neigh->dev->ifindex != oldflp->oif)) ||
1006 (oldflp->fld_src &&
1007 (!dn_dev_islocal(neigh->dev,
1008 oldflp->fld_src)))) {
1009 neigh_release(neigh);
1010 neigh = NULL;
1011 } else {
1012 if (dev_out)
1013 dev_put(dev_out);
1014 if (dn_dev_islocal(neigh->dev, fl.fld_dst)) {
1015 dev_out = init_net.loopback_dev;
1016 res.type = RTN_LOCAL;
1017 } else {
1018 dev_out = neigh->dev;
1019 }
1020 dev_hold(dev_out);
1021 goto select_source;
1022 }
1023 }
1024 }
1025
1026 /* Not there? Perhaps its a local address */
1027 if (dev_out == NULL)
1028 dev_out = dn_dev_get_default();
1029 err = -ENODEV;
1030 if (dev_out == NULL)
1031 goto out;
1032 dn_db = dev_out->dn_ptr;
1033 /* Possible improvement - check all devices for local addr */
1034 if (dn_dev_islocal(dev_out, fl.fld_dst)) {
1035 dev_put(dev_out);
1036 dev_out = init_net.loopback_dev;
1037 dev_hold(dev_out);
1038 res.type = RTN_LOCAL;
1039 goto select_source;
1040 }
1041 /* Not local either.... try sending it to the default router */
1042 neigh = neigh_clone(dn_db->router);
1043 BUG_ON(neigh && neigh->dev != dev_out);
1044
1045 /* Ok then, we assume its directly connected and move on */
1046 select_source:
1047 if (neigh)
1048 gateway = ((struct dn_neigh *)neigh)->addr;
1049 if (gateway == 0)
1050 gateway = fl.fld_dst;
1051 if (fl.fld_src == 0) {
1052 fl.fld_src = dnet_select_source(dev_out, gateway,
1053 res.type == RTN_LOCAL ?
1054 RT_SCOPE_HOST :
1055 RT_SCOPE_LINK);
1056 if (fl.fld_src == 0 && res.type != RTN_LOCAL)
1057 goto e_addr;
1058 }
1059 fl.oif = dev_out->ifindex;
1060 goto make_route;
1061 }
1062 free_res = 1;
1063
1064 if (res.type == RTN_NAT)
1065 goto e_inval;
1066
1067 if (res.type == RTN_LOCAL) {
1068 if (!fl.fld_src)
1069 fl.fld_src = fl.fld_dst;
1070 if (dev_out)
1071 dev_put(dev_out);
1072 dev_out = init_net.loopback_dev;
1073 dev_hold(dev_out);
1074 fl.oif = dev_out->ifindex;
1075 if (res.fi)
1076 dn_fib_info_put(res.fi);
1077 res.fi = NULL;
1078 goto make_route;
1079 }
1080
1081 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1082 dn_fib_select_multipath(&fl, &res);
1083
1084 /*
1085 * We could add some logic to deal with default routes here and
1086 * get rid of some of the special casing above.
1087 */
1088
1089 if (!fl.fld_src)
1090 fl.fld_src = DN_FIB_RES_PREFSRC(res);
1091
1092 if (dev_out)
1093 dev_put(dev_out);
1094 dev_out = DN_FIB_RES_DEV(res);
1095 dev_hold(dev_out);
1096 fl.oif = dev_out->ifindex;
1097 gateway = DN_FIB_RES_GW(res);
1098
1099 make_route:
1100 if (dev_out->flags & IFF_LOOPBACK)
1101 flags |= RTCF_LOCAL;
1102
1103 rt = dst_alloc(&dn_dst_ops);
1104 if (rt == NULL)
1105 goto e_nobufs;
1106
1107 atomic_set(&rt->u.dst.__refcnt, 1);
1108 rt->u.dst.flags = DST_HOST;
1109
1110 rt->fl.fld_src = oldflp->fld_src;
1111 rt->fl.fld_dst = oldflp->fld_dst;
1112 rt->fl.oif = oldflp->oif;
1113 rt->fl.iif = 0;
1114 rt->fl.mark = oldflp->mark;
1115
1116 rt->rt_saddr = fl.fld_src;
1117 rt->rt_daddr = fl.fld_dst;
1118 rt->rt_gateway = gateway ? gateway : fl.fld_dst;
1119 rt->rt_local_src = fl.fld_src;
1120
1121 rt->rt_dst_map = fl.fld_dst;
1122 rt->rt_src_map = fl.fld_src;
1123
1124 rt->u.dst.dev = dev_out;
1125 dev_hold(dev_out);
1126 rt->u.dst.neighbour = neigh;
1127 neigh = NULL;
1128
1129 rt->u.dst.lastuse = jiffies;
1130 rt->u.dst.output = dn_output;
1131 rt->u.dst.input = dn_rt_bug;
1132 rt->rt_flags = flags;
1133 if (flags & RTCF_LOCAL)
1134 rt->u.dst.input = dn_nsp_rx;
1135
1136 err = dn_rt_set_next_hop(rt, &res);
1137 if (err)
1138 goto e_neighbour;
1139
1140 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1141 dn_insert_route(rt, hash, (struct dn_route **)pprt);
1142
1143 done:
1144 if (neigh)
1145 neigh_release(neigh);
1146 if (free_res)
1147 dn_fib_res_put(&res);
1148 if (dev_out)
1149 dev_put(dev_out);
1150 out:
1151 return err;
1152
1153 e_addr:
1154 err = -EADDRNOTAVAIL;
1155 goto done;
1156 e_inval:
1157 err = -EINVAL;
1158 goto done;
1159 e_nobufs:
1160 err = -ENOBUFS;
1161 goto done;
1162 e_neighbour:
1163 dst_free(&rt->u.dst);
1164 goto e_nobufs;
1165 }
1166
1167
1168 /*
1169 * N.B. The flags may be moved into the flowi at some future stage.
1170 */
1171 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowi *flp, int flags)
1172 {
1173 unsigned hash = dn_hash(flp->fld_src, flp->fld_dst);
1174 struct dn_route *rt = NULL;
1175
1176 if (!(flags & MSG_TRYHARD)) {
1177 rcu_read_lock_bh();
1178 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt;
1179 rt = rcu_dereference(rt->u.dst.dn_next)) {
1180 if ((flp->fld_dst == rt->fl.fld_dst) &&
1181 (flp->fld_src == rt->fl.fld_src) &&
1182 (flp->mark == rt->fl.mark) &&
1183 (rt->fl.iif == 0) &&
1184 (rt->fl.oif == flp->oif)) {
1185 rt->u.dst.lastuse = jiffies;
1186 dst_hold(&rt->u.dst);
1187 rt->u.dst.__use++;
1188 rcu_read_unlock_bh();
1189 *pprt = &rt->u.dst;
1190 return 0;
1191 }
1192 }
1193 rcu_read_unlock_bh();
1194 }
1195
1196 return dn_route_output_slow(pprt, flp, flags);
1197 }
1198
1199 static int dn_route_output_key(struct dst_entry **pprt, struct flowi *flp, int flags)
1200 {
1201 int err;
1202
1203 err = __dn_route_output_key(pprt, flp, flags);
1204 if (err == 0 && flp->proto) {
1205 err = xfrm_lookup(pprt, flp, NULL, 0);
1206 }
1207 return err;
1208 }
1209
1210 int dn_route_output_sock(struct dst_entry **pprt, struct flowi *fl, struct sock *sk, int flags)
1211 {
1212 int err;
1213
1214 err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1215 if (err == 0 && fl->proto) {
1216 err = xfrm_lookup(pprt, fl, sk, !(flags & MSG_DONTWAIT));
1217 }
1218 return err;
1219 }
1220
1221 static int dn_route_input_slow(struct sk_buff *skb)
1222 {
1223 struct dn_route *rt = NULL;
1224 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1225 struct net_device *in_dev = skb->dev;
1226 struct net_device *out_dev = NULL;
1227 struct dn_dev *dn_db;
1228 struct neighbour *neigh = NULL;
1229 unsigned hash;
1230 int flags = 0;
1231 __le16 gateway = 0;
1232 __le16 local_src = 0;
1233 struct flowi fl = { .nl_u = { .dn_u =
1234 { .daddr = cb->dst,
1235 .saddr = cb->src,
1236 .scope = RT_SCOPE_UNIVERSE,
1237 } },
1238 .mark = skb->mark,
1239 .iif = skb->dev->ifindex };
1240 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1241 int err = -EINVAL;
1242 int free_res = 0;
1243
1244 dev_hold(in_dev);
1245
1246 if ((dn_db = in_dev->dn_ptr) == NULL)
1247 goto out;
1248
1249 /* Zero source addresses are not allowed */
1250 if (fl.fld_src == 0)
1251 goto out;
1252
1253 /*
1254 * In this case we've just received a packet from a source
1255 * outside ourselves pretending to come from us. We don't
1256 * allow it any further to prevent routing loops, spoofing and
1257 * other nasties. Loopback packets already have the dst attached
1258 * so this only affects packets which have originated elsewhere.
1259 */
1260 err = -ENOTUNIQ;
1261 if (dn_dev_islocal(in_dev, cb->src))
1262 goto out;
1263
1264 err = dn_fib_lookup(&fl, &res);
1265 if (err) {
1266 if (err != -ESRCH)
1267 goto out;
1268 /*
1269 * Is the destination us ?
1270 */
1271 if (!dn_dev_islocal(in_dev, cb->dst))
1272 goto e_inval;
1273
1274 res.type = RTN_LOCAL;
1275 } else {
1276 __le16 src_map = fl.fld_src;
1277 free_res = 1;
1278
1279 out_dev = DN_FIB_RES_DEV(res);
1280 if (out_dev == NULL) {
1281 if (net_ratelimit())
1282 printk(KERN_CRIT "Bug in dn_route_input_slow() "
1283 "No output device\n");
1284 goto e_inval;
1285 }
1286 dev_hold(out_dev);
1287
1288 if (res.r)
1289 src_map = fl.fld_src; /* no NAT support for now */
1290
1291 gateway = DN_FIB_RES_GW(res);
1292 if (res.type == RTN_NAT) {
1293 fl.fld_dst = dn_fib_rules_map_destination(fl.fld_dst, &res);
1294 dn_fib_res_put(&res);
1295 free_res = 0;
1296 if (dn_fib_lookup(&fl, &res))
1297 goto e_inval;
1298 free_res = 1;
1299 if (res.type != RTN_UNICAST)
1300 goto e_inval;
1301 flags |= RTCF_DNAT;
1302 gateway = fl.fld_dst;
1303 }
1304 fl.fld_src = src_map;
1305 }
1306
1307 switch(res.type) {
1308 case RTN_UNICAST:
1309 /*
1310 * Forwarding check here, we only check for forwarding
1311 * being turned off, if you want to only forward intra
1312 * area, its up to you to set the routing tables up
1313 * correctly.
1314 */
1315 if (dn_db->parms.forwarding == 0)
1316 goto e_inval;
1317
1318 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1319 dn_fib_select_multipath(&fl, &res);
1320
1321 /*
1322 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1323 * flag as a hint to set the intra-ethernet bit when
1324 * forwarding. If we've got NAT in operation, we don't do
1325 * this optimisation.
1326 */
1327 if (out_dev == in_dev && !(flags & RTCF_NAT))
1328 flags |= RTCF_DOREDIRECT;
1329
1330 local_src = DN_FIB_RES_PREFSRC(res);
1331
1332 case RTN_BLACKHOLE:
1333 case RTN_UNREACHABLE:
1334 break;
1335 case RTN_LOCAL:
1336 flags |= RTCF_LOCAL;
1337 fl.fld_src = cb->dst;
1338 fl.fld_dst = cb->src;
1339
1340 /* Routing tables gave us a gateway */
1341 if (gateway)
1342 goto make_route;
1343
1344 /* Packet was intra-ethernet, so we know its on-link */
1345 if (cb->rt_flags & DN_RT_F_IE) {
1346 gateway = cb->src;
1347 flags |= RTCF_DIRECTSRC;
1348 goto make_route;
1349 }
1350
1351 /* Use the default router if there is one */
1352 neigh = neigh_clone(dn_db->router);
1353 if (neigh) {
1354 gateway = ((struct dn_neigh *)neigh)->addr;
1355 goto make_route;
1356 }
1357
1358 /* Close eyes and pray */
1359 gateway = cb->src;
1360 flags |= RTCF_DIRECTSRC;
1361 goto make_route;
1362 default:
1363 goto e_inval;
1364 }
1365
1366 make_route:
1367 rt = dst_alloc(&dn_dst_ops);
1368 if (rt == NULL)
1369 goto e_nobufs;
1370
1371 rt->rt_saddr = fl.fld_src;
1372 rt->rt_daddr = fl.fld_dst;
1373 rt->rt_gateway = fl.fld_dst;
1374 if (gateway)
1375 rt->rt_gateway = gateway;
1376 rt->rt_local_src = local_src ? local_src : rt->rt_saddr;
1377
1378 rt->rt_dst_map = fl.fld_dst;
1379 rt->rt_src_map = fl.fld_src;
1380
1381 rt->fl.fld_src = cb->src;
1382 rt->fl.fld_dst = cb->dst;
1383 rt->fl.oif = 0;
1384 rt->fl.iif = in_dev->ifindex;
1385 rt->fl.mark = fl.mark;
1386
1387 rt->u.dst.flags = DST_HOST;
1388 rt->u.dst.neighbour = neigh;
1389 rt->u.dst.dev = out_dev;
1390 rt->u.dst.lastuse = jiffies;
1391 rt->u.dst.output = dn_rt_bug;
1392 switch(res.type) {
1393 case RTN_UNICAST:
1394 rt->u.dst.input = dn_forward;
1395 break;
1396 case RTN_LOCAL:
1397 rt->u.dst.output = dn_output;
1398 rt->u.dst.input = dn_nsp_rx;
1399 rt->u.dst.dev = in_dev;
1400 flags |= RTCF_LOCAL;
1401 break;
1402 default:
1403 case RTN_UNREACHABLE:
1404 case RTN_BLACKHOLE:
1405 rt->u.dst.input = dn_blackhole;
1406 }
1407 rt->rt_flags = flags;
1408 if (rt->u.dst.dev)
1409 dev_hold(rt->u.dst.dev);
1410
1411 err = dn_rt_set_next_hop(rt, &res);
1412 if (err)
1413 goto e_neighbour;
1414
1415 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1416 dn_insert_route(rt, hash, (struct dn_route **)&skb->dst);
1417
1418 done:
1419 if (neigh)
1420 neigh_release(neigh);
1421 if (free_res)
1422 dn_fib_res_put(&res);
1423 dev_put(in_dev);
1424 if (out_dev)
1425 dev_put(out_dev);
1426 out:
1427 return err;
1428
1429 e_inval:
1430 err = -EINVAL;
1431 goto done;
1432
1433 e_nobufs:
1434 err = -ENOBUFS;
1435 goto done;
1436
1437 e_neighbour:
1438 dst_free(&rt->u.dst);
1439 goto done;
1440 }
1441
1442 int dn_route_input(struct sk_buff *skb)
1443 {
1444 struct dn_route *rt;
1445 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1446 unsigned hash = dn_hash(cb->src, cb->dst);
1447
1448 if (skb->dst)
1449 return 0;
1450
1451 rcu_read_lock();
1452 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1453 rt = rcu_dereference(rt->u.dst.dn_next)) {
1454 if ((rt->fl.fld_src == cb->src) &&
1455 (rt->fl.fld_dst == cb->dst) &&
1456 (rt->fl.oif == 0) &&
1457 (rt->fl.mark == skb->mark) &&
1458 (rt->fl.iif == cb->iif)) {
1459 rt->u.dst.lastuse = jiffies;
1460 dst_hold(&rt->u.dst);
1461 rt->u.dst.__use++;
1462 rcu_read_unlock();
1463 skb->dst = (struct dst_entry *)rt;
1464 return 0;
1465 }
1466 }
1467 rcu_read_unlock();
1468
1469 return dn_route_input_slow(skb);
1470 }
1471
1472 static int dn_rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1473 int event, int nowait, unsigned int flags)
1474 {
1475 struct dn_route *rt = (struct dn_route *)skb->dst;
1476 struct rtmsg *r;
1477 struct nlmsghdr *nlh;
1478 unsigned char *b = skb_tail_pointer(skb);
1479 long expires;
1480
1481 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
1482 r = NLMSG_DATA(nlh);
1483 r->rtm_family = AF_DECnet;
1484 r->rtm_dst_len = 16;
1485 r->rtm_src_len = 0;
1486 r->rtm_tos = 0;
1487 r->rtm_table = RT_TABLE_MAIN;
1488 RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
1489 r->rtm_type = rt->rt_type;
1490 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1491 r->rtm_scope = RT_SCOPE_UNIVERSE;
1492 r->rtm_protocol = RTPROT_UNSPEC;
1493 if (rt->rt_flags & RTCF_NOTIFY)
1494 r->rtm_flags |= RTM_F_NOTIFY;
1495 RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr);
1496 if (rt->fl.fld_src) {
1497 r->rtm_src_len = 16;
1498 RTA_PUT(skb, RTA_SRC, 2, &rt->fl.fld_src);
1499 }
1500 if (rt->u.dst.dev)
1501 RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->u.dst.dev->ifindex);
1502 /*
1503 * Note to self - change this if input routes reverse direction when
1504 * they deal only with inputs and not with replies like they do
1505 * currently.
1506 */
1507 RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src);
1508 if (rt->rt_daddr != rt->rt_gateway)
1509 RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway);
1510 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
1511 goto rtattr_failure;
1512 expires = rt->u.dst.expires ? rt->u.dst.expires - jiffies : 0;
1513 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0, expires,
1514 rt->u.dst.error) < 0)
1515 goto rtattr_failure;
1516 if (rt->fl.iif)
1517 RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fl.iif);
1518
1519 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1520 return skb->len;
1521
1522 nlmsg_failure:
1523 rtattr_failure:
1524 nlmsg_trim(skb, b);
1525 return -1;
1526 }
1527
1528 /*
1529 * This is called by both endnodes and routers now.
1530 */
1531 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
1532 {
1533 struct rtattr **rta = arg;
1534 struct rtmsg *rtm = NLMSG_DATA(nlh);
1535 struct dn_route *rt = NULL;
1536 struct dn_skb_cb *cb;
1537 int err;
1538 struct sk_buff *skb;
1539 struct flowi fl;
1540
1541 memset(&fl, 0, sizeof(fl));
1542 fl.proto = DNPROTO_NSP;
1543
1544 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1545 if (skb == NULL)
1546 return -ENOBUFS;
1547 skb_reset_mac_header(skb);
1548 cb = DN_SKB_CB(skb);
1549
1550 if (rta[RTA_SRC-1])
1551 memcpy(&fl.fld_src, RTA_DATA(rta[RTA_SRC-1]), 2);
1552 if (rta[RTA_DST-1])
1553 memcpy(&fl.fld_dst, RTA_DATA(rta[RTA_DST-1]), 2);
1554 if (rta[RTA_IIF-1])
1555 memcpy(&fl.iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
1556
1557 if (fl.iif) {
1558 struct net_device *dev;
1559 if ((dev = dev_get_by_index(&init_net, fl.iif)) == NULL) {
1560 kfree_skb(skb);
1561 return -ENODEV;
1562 }
1563 if (!dev->dn_ptr) {
1564 dev_put(dev);
1565 kfree_skb(skb);
1566 return -ENODEV;
1567 }
1568 skb->protocol = __constant_htons(ETH_P_DNA_RT);
1569 skb->dev = dev;
1570 cb->src = fl.fld_src;
1571 cb->dst = fl.fld_dst;
1572 local_bh_disable();
1573 err = dn_route_input(skb);
1574 local_bh_enable();
1575 memset(cb, 0, sizeof(struct dn_skb_cb));
1576 rt = (struct dn_route *)skb->dst;
1577 if (!err && -rt->u.dst.error)
1578 err = rt->u.dst.error;
1579 } else {
1580 int oif = 0;
1581 if (rta[RTA_OIF - 1])
1582 memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
1583 fl.oif = oif;
1584 err = dn_route_output_key((struct dst_entry **)&rt, &fl, 0);
1585 }
1586
1587 if (skb->dev)
1588 dev_put(skb->dev);
1589 skb->dev = NULL;
1590 if (err)
1591 goto out_free;
1592 skb->dst = &rt->u.dst;
1593 if (rtm->rtm_flags & RTM_F_NOTIFY)
1594 rt->rt_flags |= RTCF_NOTIFY;
1595
1596 err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1597
1598 if (err == 0)
1599 goto out_free;
1600 if (err < 0) {
1601 err = -EMSGSIZE;
1602 goto out_free;
1603 }
1604
1605 return rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
1606
1607 out_free:
1608 kfree_skb(skb);
1609 return err;
1610 }
1611
1612 /*
1613 * For routers, this is called from dn_fib_dump, but for endnodes its
1614 * called directly from the rtnetlink dispatch table.
1615 */
1616 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1617 {
1618 struct dn_route *rt;
1619 int h, s_h;
1620 int idx, s_idx;
1621
1622 if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg))
1623 return -EINVAL;
1624 if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED))
1625 return 0;
1626
1627 s_h = cb->args[0];
1628 s_idx = idx = cb->args[1];
1629 for(h = 0; h <= dn_rt_hash_mask; h++) {
1630 if (h < s_h)
1631 continue;
1632 if (h > s_h)
1633 s_idx = 0;
1634 rcu_read_lock_bh();
1635 for(rt = rcu_dereference(dn_rt_hash_table[h].chain), idx = 0;
1636 rt;
1637 rt = rcu_dereference(rt->u.dst.dn_next), idx++) {
1638 if (idx < s_idx)
1639 continue;
1640 skb->dst = dst_clone(&rt->u.dst);
1641 if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
1642 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1643 1, NLM_F_MULTI) <= 0) {
1644 dst_release(xchg(&skb->dst, NULL));
1645 rcu_read_unlock_bh();
1646 goto done;
1647 }
1648 dst_release(xchg(&skb->dst, NULL));
1649 }
1650 rcu_read_unlock_bh();
1651 }
1652
1653 done:
1654 cb->args[0] = h;
1655 cb->args[1] = idx;
1656 return skb->len;
1657 }
1658
1659 #ifdef CONFIG_PROC_FS
1660 struct dn_rt_cache_iter_state {
1661 int bucket;
1662 };
1663
1664 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1665 {
1666 struct dn_route *rt = NULL;
1667 struct dn_rt_cache_iter_state *s = seq->private;
1668
1669 for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1670 rcu_read_lock_bh();
1671 rt = dn_rt_hash_table[s->bucket].chain;
1672 if (rt)
1673 break;
1674 rcu_read_unlock_bh();
1675 }
1676 return rt;
1677 }
1678
1679 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1680 {
1681 struct dn_rt_cache_iter_state *s = rcu_dereference(seq->private);
1682
1683 rt = rt->u.dst.dn_next;
1684 while(!rt) {
1685 rcu_read_unlock_bh();
1686 if (--s->bucket < 0)
1687 break;
1688 rcu_read_lock_bh();
1689 rt = dn_rt_hash_table[s->bucket].chain;
1690 }
1691 return rt;
1692 }
1693
1694 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1695 {
1696 struct dn_route *rt = dn_rt_cache_get_first(seq);
1697
1698 if (rt) {
1699 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1700 --*pos;
1701 }
1702 return *pos ? NULL : rt;
1703 }
1704
1705 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1706 {
1707 struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1708 ++*pos;
1709 return rt;
1710 }
1711
1712 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1713 {
1714 if (v)
1715 rcu_read_unlock_bh();
1716 }
1717
1718 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1719 {
1720 struct dn_route *rt = v;
1721 char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1722
1723 seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1724 rt->u.dst.dev ? rt->u.dst.dev->name : "*",
1725 dn_addr2asc(dn_ntohs(rt->rt_daddr), buf1),
1726 dn_addr2asc(dn_ntohs(rt->rt_saddr), buf2),
1727 atomic_read(&rt->u.dst.__refcnt),
1728 rt->u.dst.__use,
1729 (int) dst_metric(&rt->u.dst, RTAX_RTT));
1730 return 0;
1731 }
1732
1733 static const struct seq_operations dn_rt_cache_seq_ops = {
1734 .start = dn_rt_cache_seq_start,
1735 .next = dn_rt_cache_seq_next,
1736 .stop = dn_rt_cache_seq_stop,
1737 .show = dn_rt_cache_seq_show,
1738 };
1739
1740 static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1741 {
1742 return seq_open_private(file, &dn_rt_cache_seq_ops,
1743 sizeof(struct dn_rt_cache_iter_state));
1744 }
1745
1746 static const struct file_operations dn_rt_cache_seq_fops = {
1747 .owner = THIS_MODULE,
1748 .open = dn_rt_cache_seq_open,
1749 .read = seq_read,
1750 .llseek = seq_lseek,
1751 .release = seq_release_private,
1752 };
1753
1754 #endif /* CONFIG_PROC_FS */
1755
1756 void __init dn_route_init(void)
1757 {
1758 int i, goal, order;
1759
1760 dn_dst_ops.kmem_cachep =
1761 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1762 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1763 init_timer(&dn_route_timer);
1764 dn_route_timer.function = dn_dst_check_expire;
1765 dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1766 add_timer(&dn_route_timer);
1767
1768 goal = num_physpages >> (26 - PAGE_SHIFT);
1769
1770 for(order = 0; (1UL << order) < goal; order++)
1771 /* NOTHING */;
1772
1773 /*
1774 * Only want 1024 entries max, since the table is very, very unlikely
1775 * to be larger than that.
1776 */
1777 while(order && ((((1UL << order) * PAGE_SIZE) /
1778 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1779 order--;
1780
1781 do {
1782 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1783 sizeof(struct dn_rt_hash_bucket);
1784 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1785 dn_rt_hash_mask--;
1786 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1787 __get_free_pages(GFP_ATOMIC, order);
1788 } while (dn_rt_hash_table == NULL && --order > 0);
1789
1790 if (!dn_rt_hash_table)
1791 panic("Failed to allocate DECnet route cache hash table\n");
1792
1793 printk(KERN_INFO
1794 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1795 dn_rt_hash_mask,
1796 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1797
1798 dn_rt_hash_mask--;
1799 for(i = 0; i <= dn_rt_hash_mask; i++) {
1800 spin_lock_init(&dn_rt_hash_table[i].lock);
1801 dn_rt_hash_table[i].chain = NULL;
1802 }
1803
1804 dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1805
1806 proc_net_fops_create(&init_net, "decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
1807
1808 #ifdef CONFIG_DECNET_ROUTER
1809 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute, dn_fib_dump);
1810 #else
1811 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1812 dn_cache_dump);
1813 #endif
1814 }
1815
1816 void __exit dn_route_cleanup(void)
1817 {
1818 del_timer(&dn_route_timer);
1819 dn_run_flush(0);
1820
1821 proc_net_remove(&init_net, "decnet_cache");
1822 }
1823
kmemtrace - Kernel memory tracer