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Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/inaky/wimax
[mirror_ubuntu-zesty-kernel.git] / net / decnet / dn_route.c
1 /*
2 * DECnet An implementation of the DECnet protocol suite for the LINUX
3 * operating system. DECnet is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * DECnet Routing Functions (Endnode and Router)
7 *
8 * Authors: Steve Whitehouse <SteveW@ACM.org>
9 * Eduardo Marcelo Serrat <emserrat@geocities.com>
10 *
11 * Changes:
12 * Steve Whitehouse : Fixes to allow "intra-ethernet" and
13 * "return-to-sender" bits on outgoing
14 * packets.
15 * Steve Whitehouse : Timeouts for cached routes.
16 * Steve Whitehouse : Use dst cache for input routes too.
17 * Steve Whitehouse : Fixed error values in dn_send_skb.
18 * Steve Whitehouse : Rework routing functions to better fit
19 * DECnet routing design
20 * Alexey Kuznetsov : New SMP locking
21 * Steve Whitehouse : More SMP locking changes & dn_cache_dump()
22 * Steve Whitehouse : Prerouting NF hook, now really is prerouting.
23 * Fixed possible skb leak in rtnetlink funcs.
24 * Steve Whitehouse : Dave Miller's dynamic hash table sizing and
25 * Alexey Kuznetsov's finer grained locking
26 * from ipv4/route.c.
27 * Steve Whitehouse : Routing is now starting to look like a
28 * sensible set of code now, mainly due to
29 * my copying the IPv4 routing code. The
30 * hooks here are modified and will continue
31 * to evolve for a while.
32 * Steve Whitehouse : Real SMP at last :-) Also new netfilter
33 * stuff. Look out raw sockets your days
34 * are numbered!
35 * Steve Whitehouse : Added return-to-sender functions. Added
36 * backlog congestion level return codes.
37 * Steve Whitehouse : Fixed bug where routes were set up with
38 * no ref count on net devices.
39 * Steve Whitehouse : RCU for the route cache
40 * Steve Whitehouse : Preparations for the flow cache
41 * Steve Whitehouse : Prepare for nonlinear skbs
42 */
43
44 /******************************************************************************
45 (c) 1995-1998 E.M. Serrat emserrat@geocities.com
46
47 This program is free software; you can redistribute it and/or modify
48 it under the terms of the GNU General Public License as published by
49 the Free Software Foundation; either version 2 of the License, or
50 any later version.
51
52 This program is distributed in the hope that it will be useful,
53 but WITHOUT ANY WARRANTY; without even the implied warranty of
54 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
55 GNU General Public License for more details.
56 *******************************************************************************/
57
58 #include <linux/errno.h>
59 #include <linux/types.h>
60 #include <linux/socket.h>
61 #include <linux/in.h>
62 #include <linux/kernel.h>
63 #include <linux/sockios.h>
64 #include <linux/net.h>
65 #include <linux/netdevice.h>
66 #include <linux/inet.h>
67 #include <linux/route.h>
68 #include <linux/in_route.h>
69 #include <linux/slab.h>
70 #include <net/sock.h>
71 #include <linux/mm.h>
72 #include <linux/proc_fs.h>
73 #include <linux/seq_file.h>
74 #include <linux/init.h>
75 #include <linux/rtnetlink.h>
76 #include <linux/string.h>
77 #include <linux/netfilter_decnet.h>
78 #include <linux/rcupdate.h>
79 #include <linux/times.h>
80 #include <asm/errno.h>
81 #include <net/net_namespace.h>
82 #include <net/netlink.h>
83 #include <net/neighbour.h>
84 #include <net/dst.h>
85 #include <net/flow.h>
86 #include <net/fib_rules.h>
87 #include <net/dn.h>
88 #include <net/dn_dev.h>
89 #include <net/dn_nsp.h>
90 #include <net/dn_route.h>
91 #include <net/dn_neigh.h>
92 #include <net/dn_fib.h>
93
94 struct dn_rt_hash_bucket
95 {
96 struct dn_route *chain;
97 spinlock_t lock;
98 };
99
100 extern struct neigh_table dn_neigh_table;
101
102
103 static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
104
105 static const int dn_rt_min_delay = 2 * HZ;
106 static const int dn_rt_max_delay = 10 * HZ;
107 static const int dn_rt_mtu_expires = 10 * 60 * HZ;
108
109 static unsigned long dn_rt_deadline;
110
111 static int dn_dst_gc(struct dst_ops *ops);
112 static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
113 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
114 static void dn_dst_link_failure(struct sk_buff *);
115 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
116 static int dn_route_input(struct sk_buff *);
117 static void dn_run_flush(unsigned long dummy);
118
119 static struct dn_rt_hash_bucket *dn_rt_hash_table;
120 static unsigned dn_rt_hash_mask;
121
122 static struct timer_list dn_route_timer;
123 static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
124 int decnet_dst_gc_interval = 2;
125
126 static struct dst_ops dn_dst_ops = {
127 .family = PF_DECnet,
128 .protocol = cpu_to_be16(ETH_P_DNA_RT),
129 .gc_thresh = 128,
130 .gc = dn_dst_gc,
131 .check = dn_dst_check,
132 .negative_advice = dn_dst_negative_advice,
133 .link_failure = dn_dst_link_failure,
134 .update_pmtu = dn_dst_update_pmtu,
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(struct dst_ops *ops)
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_metric(dst, RTAX_MTU) > 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_metric(dst, RTAX_ADVMSS) > 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 dst_use(&rth->u.dst, now);
297 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
298
299 dnrt_drop(rt);
300 *rp = rth;
301 return 0;
302 }
303 rthp = &rth->u.dst.dn_next;
304 }
305
306 rcu_assign_pointer(rt->u.dst.dn_next, dn_rt_hash_table[hash].chain);
307 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
308
309 dst_use(&rt->u.dst, now);
310 spin_unlock_bh(&dn_rt_hash_table[hash].lock);
311 *rp = rt;
312 return 0;
313 }
314
315 static void dn_run_flush(unsigned long dummy)
316 {
317 int i;
318 struct dn_route *rt, *next;
319
320 for(i = 0; i < dn_rt_hash_mask; i++) {
321 spin_lock_bh(&dn_rt_hash_table[i].lock);
322
323 if ((rt = xchg(&dn_rt_hash_table[i].chain, NULL)) == NULL)
324 goto nothing_to_declare;
325
326 for(; rt; rt=next) {
327 next = rt->u.dst.dn_next;
328 rt->u.dst.dn_next = NULL;
329 dst_free((struct dst_entry *)rt);
330 }
331
332 nothing_to_declare:
333 spin_unlock_bh(&dn_rt_hash_table[i].lock);
334 }
335 }
336
337 static DEFINE_SPINLOCK(dn_rt_flush_lock);
338
339 void dn_rt_cache_flush(int delay)
340 {
341 unsigned long now = jiffies;
342 int user_mode = !in_interrupt();
343
344 if (delay < 0)
345 delay = dn_rt_min_delay;
346
347 spin_lock_bh(&dn_rt_flush_lock);
348
349 if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
350 long tmo = (long)(dn_rt_deadline - now);
351
352 if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
353 tmo = 0;
354
355 if (delay > tmo)
356 delay = tmo;
357 }
358
359 if (delay <= 0) {
360 spin_unlock_bh(&dn_rt_flush_lock);
361 dn_run_flush(0);
362 return;
363 }
364
365 if (dn_rt_deadline == 0)
366 dn_rt_deadline = now + dn_rt_max_delay;
367
368 dn_rt_flush_timer.expires = now + delay;
369 add_timer(&dn_rt_flush_timer);
370 spin_unlock_bh(&dn_rt_flush_lock);
371 }
372
373 /**
374 * dn_return_short - Return a short packet to its sender
375 * @skb: The packet to return
376 *
377 */
378 static int dn_return_short(struct sk_buff *skb)
379 {
380 struct dn_skb_cb *cb;
381 unsigned char *ptr;
382 __le16 *src;
383 __le16 *dst;
384
385 /* Add back headers */
386 skb_push(skb, skb->data - skb_network_header(skb));
387
388 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
389 return NET_RX_DROP;
390
391 cb = DN_SKB_CB(skb);
392 /* Skip packet length and point to flags */
393 ptr = skb->data + 2;
394 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
395
396 dst = (__le16 *)ptr;
397 ptr += 2;
398 src = (__le16 *)ptr;
399 ptr += 2;
400 *ptr = 0; /* Zero hop count */
401
402 swap(*src, *dst);
403
404 skb->pkt_type = PACKET_OUTGOING;
405 dn_rt_finish_output(skb, NULL, NULL);
406 return NET_RX_SUCCESS;
407 }
408
409 /**
410 * dn_return_long - Return a long packet to its sender
411 * @skb: The long format packet to return
412 *
413 */
414 static int dn_return_long(struct sk_buff *skb)
415 {
416 struct dn_skb_cb *cb;
417 unsigned char *ptr;
418 unsigned char *src_addr, *dst_addr;
419 unsigned char tmp[ETH_ALEN];
420
421 /* Add back all headers */
422 skb_push(skb, skb->data - skb_network_header(skb));
423
424 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
425 return NET_RX_DROP;
426
427 cb = DN_SKB_CB(skb);
428 /* Ignore packet length and point to flags */
429 ptr = skb->data + 2;
430
431 /* Skip padding */
432 if (*ptr & DN_RT_F_PF) {
433 char padlen = (*ptr & ~DN_RT_F_PF);
434 ptr += padlen;
435 }
436
437 *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
438 ptr += 2;
439 dst_addr = ptr;
440 ptr += 8;
441 src_addr = ptr;
442 ptr += 6;
443 *ptr = 0; /* Zero hop count */
444
445 /* Swap source and destination */
446 memcpy(tmp, src_addr, ETH_ALEN);
447 memcpy(src_addr, dst_addr, ETH_ALEN);
448 memcpy(dst_addr, tmp, ETH_ALEN);
449
450 skb->pkt_type = PACKET_OUTGOING;
451 dn_rt_finish_output(skb, dst_addr, src_addr);
452 return NET_RX_SUCCESS;
453 }
454
455 /**
456 * dn_route_rx_packet - Try and find a route for an incoming packet
457 * @skb: The packet to find a route for
458 *
459 * Returns: result of input function if route is found, error code otherwise
460 */
461 static int dn_route_rx_packet(struct sk_buff *skb)
462 {
463 struct dn_skb_cb *cb = DN_SKB_CB(skb);
464 int err;
465
466 if ((err = dn_route_input(skb)) == 0)
467 return dst_input(skb);
468
469 if (decnet_debug_level & 4) {
470 char *devname = skb->dev ? skb->dev->name : "???";
471 struct dn_skb_cb *cb = DN_SKB_CB(skb);
472 printk(KERN_DEBUG
473 "DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
474 (int)cb->rt_flags, devname, skb->len,
475 le16_to_cpu(cb->src), le16_to_cpu(cb->dst),
476 err, skb->pkt_type);
477 }
478
479 if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
480 switch(cb->rt_flags & DN_RT_PKT_MSK) {
481 case DN_RT_PKT_SHORT:
482 return dn_return_short(skb);
483 case DN_RT_PKT_LONG:
484 return dn_return_long(skb);
485 }
486 }
487
488 kfree_skb(skb);
489 return NET_RX_DROP;
490 }
491
492 static int dn_route_rx_long(struct sk_buff *skb)
493 {
494 struct dn_skb_cb *cb = DN_SKB_CB(skb);
495 unsigned char *ptr = skb->data;
496
497 if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
498 goto drop_it;
499
500 skb_pull(skb, 20);
501 skb_reset_transport_header(skb);
502
503 /* Destination info */
504 ptr += 2;
505 cb->dst = dn_eth2dn(ptr);
506 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
507 goto drop_it;
508 ptr += 6;
509
510
511 /* Source info */
512 ptr += 2;
513 cb->src = dn_eth2dn(ptr);
514 if (memcmp(ptr, dn_hiord_addr, 4) != 0)
515 goto drop_it;
516 ptr += 6;
517 /* Other junk */
518 ptr++;
519 cb->hops = *ptr++; /* Visit Count */
520
521 return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, skb, skb->dev, NULL,
522 dn_route_rx_packet);
523
524 drop_it:
525 kfree_skb(skb);
526 return NET_RX_DROP;
527 }
528
529
530
531 static int dn_route_rx_short(struct sk_buff *skb)
532 {
533 struct dn_skb_cb *cb = DN_SKB_CB(skb);
534 unsigned char *ptr = skb->data;
535
536 if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
537 goto drop_it;
538
539 skb_pull(skb, 5);
540 skb_reset_transport_header(skb);
541
542 cb->dst = *(__le16 *)ptr;
543 ptr += 2;
544 cb->src = *(__le16 *)ptr;
545 ptr += 2;
546 cb->hops = *ptr & 0x3f;
547
548 return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, skb, skb->dev, NULL,
549 dn_route_rx_packet);
550
551 drop_it:
552 kfree_skb(skb);
553 return NET_RX_DROP;
554 }
555
556 static int dn_route_discard(struct sk_buff *skb)
557 {
558 /*
559 * I know we drop the packet here, but thats considered success in
560 * this case
561 */
562 kfree_skb(skb);
563 return NET_RX_SUCCESS;
564 }
565
566 static int dn_route_ptp_hello(struct sk_buff *skb)
567 {
568 dn_dev_hello(skb);
569 dn_neigh_pointopoint_hello(skb);
570 return NET_RX_SUCCESS;
571 }
572
573 int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
574 {
575 struct dn_skb_cb *cb;
576 unsigned char flags = 0;
577 __u16 len = le16_to_cpu(*(__le16 *)skb->data);
578 struct dn_dev *dn = (struct dn_dev *)dev->dn_ptr;
579 unsigned char padlen = 0;
580
581 if (!net_eq(dev_net(dev), &init_net))
582 goto dump_it;
583
584 if (dn == NULL)
585 goto dump_it;
586
587 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
588 goto out;
589
590 if (!pskb_may_pull(skb, 3))
591 goto dump_it;
592
593 skb_pull(skb, 2);
594
595 if (len > skb->len)
596 goto dump_it;
597
598 skb_trim(skb, len);
599
600 flags = *skb->data;
601
602 cb = DN_SKB_CB(skb);
603 cb->stamp = jiffies;
604 cb->iif = dev->ifindex;
605
606 /*
607 * If we have padding, remove it.
608 */
609 if (flags & DN_RT_F_PF) {
610 padlen = flags & ~DN_RT_F_PF;
611 if (!pskb_may_pull(skb, padlen + 1))
612 goto dump_it;
613 skb_pull(skb, padlen);
614 flags = *skb->data;
615 }
616
617 skb_reset_network_header(skb);
618
619 /*
620 * Weed out future version DECnet
621 */
622 if (flags & DN_RT_F_VER)
623 goto dump_it;
624
625 cb->rt_flags = flags;
626
627 if (decnet_debug_level & 1)
628 printk(KERN_DEBUG
629 "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
630 (int)flags, (dev) ? dev->name : "???", len, skb->len,
631 padlen);
632
633 if (flags & DN_RT_PKT_CNTL) {
634 if (unlikely(skb_linearize(skb)))
635 goto dump_it;
636
637 switch(flags & DN_RT_CNTL_MSK) {
638 case DN_RT_PKT_INIT:
639 dn_dev_init_pkt(skb);
640 break;
641 case DN_RT_PKT_VERI:
642 dn_dev_veri_pkt(skb);
643 break;
644 }
645
646 if (dn->parms.state != DN_DEV_S_RU)
647 goto dump_it;
648
649 switch(flags & DN_RT_CNTL_MSK) {
650 case DN_RT_PKT_HELO:
651 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
652 skb, skb->dev, NULL,
653 dn_route_ptp_hello);
654
655 case DN_RT_PKT_L1RT:
656 case DN_RT_PKT_L2RT:
657 return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE,
658 skb, skb->dev, NULL,
659 dn_route_discard);
660 case DN_RT_PKT_ERTH:
661 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
662 skb, skb->dev, NULL,
663 dn_neigh_router_hello);
664
665 case DN_RT_PKT_EEDH:
666 return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
667 skb, skb->dev, NULL,
668 dn_neigh_endnode_hello);
669 }
670 } else {
671 if (dn->parms.state != DN_DEV_S_RU)
672 goto dump_it;
673
674 skb_pull(skb, 1); /* Pull flags */
675
676 switch(flags & DN_RT_PKT_MSK) {
677 case DN_RT_PKT_LONG:
678 return dn_route_rx_long(skb);
679 case DN_RT_PKT_SHORT:
680 return dn_route_rx_short(skb);
681 }
682 }
683
684 dump_it:
685 kfree_skb(skb);
686 out:
687 return NET_RX_DROP;
688 }
689
690 static int dn_output(struct sk_buff *skb)
691 {
692 struct dst_entry *dst = skb_dst(skb);
693 struct dn_route *rt = (struct dn_route *)dst;
694 struct net_device *dev = dst->dev;
695 struct dn_skb_cb *cb = DN_SKB_CB(skb);
696 struct neighbour *neigh;
697
698 int err = -EINVAL;
699
700 if ((neigh = dst->neighbour) == NULL)
701 goto error;
702
703 skb->dev = dev;
704
705 cb->src = rt->rt_saddr;
706 cb->dst = rt->rt_daddr;
707
708 /*
709 * Always set the Intra-Ethernet bit on all outgoing packets
710 * originated on this node. Only valid flag from upper layers
711 * is return-to-sender-requested. Set hop count to 0 too.
712 */
713 cb->rt_flags &= ~DN_RT_F_RQR;
714 cb->rt_flags |= DN_RT_F_IE;
715 cb->hops = 0;
716
717 return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT, skb, NULL, dev,
718 neigh->output);
719
720 error:
721 if (net_ratelimit())
722 printk(KERN_DEBUG "dn_output: This should not happen\n");
723
724 kfree_skb(skb);
725
726 return err;
727 }
728
729 static int dn_forward(struct sk_buff *skb)
730 {
731 struct dn_skb_cb *cb = DN_SKB_CB(skb);
732 struct dst_entry *dst = skb_dst(skb);
733 struct dn_dev *dn_db = dst->dev->dn_ptr;
734 struct dn_route *rt;
735 struct neighbour *neigh = dst->neighbour;
736 int header_len;
737 #ifdef CONFIG_NETFILTER
738 struct net_device *dev = skb->dev;
739 #endif
740
741 if (skb->pkt_type != PACKET_HOST)
742 goto drop;
743
744 /* Ensure that we have enough space for headers */
745 rt = (struct dn_route *)skb_dst(skb);
746 header_len = dn_db->use_long ? 21 : 6;
747 if (skb_cow(skb, LL_RESERVED_SPACE(rt->u.dst.dev)+header_len))
748 goto drop;
749
750 /*
751 * Hop count exceeded.
752 */
753 if (++cb->hops > 30)
754 goto drop;
755
756 skb->dev = rt->u.dst.dev;
757
758 /*
759 * If packet goes out same interface it came in on, then set
760 * the Intra-Ethernet bit. This has no effect for short
761 * packets, so we don't need to test for them here.
762 */
763 cb->rt_flags &= ~DN_RT_F_IE;
764 if (rt->rt_flags & RTCF_DOREDIRECT)
765 cb->rt_flags |= DN_RT_F_IE;
766
767 return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD, skb, dev, skb->dev,
768 neigh->output);
769
770 drop:
771 kfree_skb(skb);
772 return NET_RX_DROP;
773 }
774
775 /*
776 * Used to catch bugs. This should never normally get
777 * called.
778 */
779 static int dn_rt_bug(struct sk_buff *skb)
780 {
781 if (net_ratelimit()) {
782 struct dn_skb_cb *cb = DN_SKB_CB(skb);
783
784 printk(KERN_DEBUG "dn_rt_bug: skb from:%04x to:%04x\n",
785 le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
786 }
787
788 kfree_skb(skb);
789
790 return NET_RX_DROP;
791 }
792
793 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
794 {
795 struct dn_fib_info *fi = res->fi;
796 struct net_device *dev = rt->u.dst.dev;
797 struct neighbour *n;
798 unsigned mss;
799
800 if (fi) {
801 if (DN_FIB_RES_GW(*res) &&
802 DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
803 rt->rt_gateway = DN_FIB_RES_GW(*res);
804 memcpy(rt->u.dst.metrics, fi->fib_metrics,
805 sizeof(rt->u.dst.metrics));
806 }
807 rt->rt_type = res->type;
808
809 if (dev != NULL && rt->u.dst.neighbour == NULL) {
810 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
811 if (IS_ERR(n))
812 return PTR_ERR(n);
813 rt->u.dst.neighbour = n;
814 }
815
816 if (dst_metric(&rt->u.dst, RTAX_MTU) == 0 ||
817 dst_metric(&rt->u.dst, RTAX_MTU) > rt->u.dst.dev->mtu)
818 rt->u.dst.metrics[RTAX_MTU-1] = rt->u.dst.dev->mtu;
819 mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->u.dst));
820 if (dst_metric(&rt->u.dst, RTAX_ADVMSS) == 0 ||
821 dst_metric(&rt->u.dst, RTAX_ADVMSS) > mss)
822 rt->u.dst.metrics[RTAX_ADVMSS-1] = mss;
823 return 0;
824 }
825
826 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
827 {
828 __u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
829 int match = 16;
830 while(tmp) {
831 tmp >>= 1;
832 match--;
833 }
834 return match;
835 }
836
837 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
838 {
839 __le16 saddr = 0;
840 struct dn_dev *dn_db = dev->dn_ptr;
841 struct dn_ifaddr *ifa;
842 int best_match = 0;
843 int ret;
844
845 read_lock(&dev_base_lock);
846 for(ifa = dn_db->ifa_list; ifa; ifa = ifa->ifa_next) {
847 if (ifa->ifa_scope > scope)
848 continue;
849 if (!daddr) {
850 saddr = ifa->ifa_local;
851 break;
852 }
853 ret = dn_match_addr(daddr, ifa->ifa_local);
854 if (ret > best_match)
855 saddr = ifa->ifa_local;
856 if (best_match == 0)
857 saddr = ifa->ifa_local;
858 }
859 read_unlock(&dev_base_lock);
860
861 return saddr;
862 }
863
864 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
865 {
866 return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
867 }
868
869 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
870 {
871 __le16 mask = dnet_make_mask(res->prefixlen);
872 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
873 }
874
875 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *oldflp, int try_hard)
876 {
877 struct flowi fl = { .nl_u = { .dn_u =
878 { .daddr = oldflp->fld_dst,
879 .saddr = oldflp->fld_src,
880 .scope = RT_SCOPE_UNIVERSE,
881 } },
882 .mark = oldflp->mark,
883 .iif = init_net.loopback_dev->ifindex,
884 .oif = oldflp->oif };
885 struct dn_route *rt = NULL;
886 struct net_device *dev_out = NULL, *dev;
887 struct neighbour *neigh = NULL;
888 unsigned hash;
889 unsigned flags = 0;
890 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
891 int err;
892 int free_res = 0;
893 __le16 gateway = 0;
894
895 if (decnet_debug_level & 16)
896 printk(KERN_DEBUG
897 "dn_route_output_slow: dst=%04x src=%04x mark=%d"
898 " iif=%d oif=%d\n", le16_to_cpu(oldflp->fld_dst),
899 le16_to_cpu(oldflp->fld_src),
900 oldflp->mark, init_net.loopback_dev->ifindex, oldflp->oif);
901
902 /* If we have an output interface, verify its a DECnet device */
903 if (oldflp->oif) {
904 dev_out = dev_get_by_index(&init_net, oldflp->oif);
905 err = -ENODEV;
906 if (dev_out && dev_out->dn_ptr == NULL) {
907 dev_put(dev_out);
908 dev_out = NULL;
909 }
910 if (dev_out == NULL)
911 goto out;
912 }
913
914 /* If we have a source address, verify that its a local address */
915 if (oldflp->fld_src) {
916 err = -EADDRNOTAVAIL;
917
918 if (dev_out) {
919 if (dn_dev_islocal(dev_out, oldflp->fld_src))
920 goto source_ok;
921 dev_put(dev_out);
922 goto out;
923 }
924 rcu_read_lock();
925 for_each_netdev_rcu(&init_net, dev) {
926 if (!dev->dn_ptr)
927 continue;
928 if (!dn_dev_islocal(dev, oldflp->fld_src))
929 continue;
930 if ((dev->flags & IFF_LOOPBACK) &&
931 oldflp->fld_dst &&
932 !dn_dev_islocal(dev, oldflp->fld_dst))
933 continue;
934
935 dev_out = dev;
936 break;
937 }
938 rcu_read_unlock();
939 if (dev_out == NULL)
940 goto out;
941 dev_hold(dev_out);
942 source_ok:
943 ;
944 }
945
946 /* No destination? Assume its local */
947 if (!fl.fld_dst) {
948 fl.fld_dst = fl.fld_src;
949
950 err = -EADDRNOTAVAIL;
951 if (dev_out)
952 dev_put(dev_out);
953 dev_out = init_net.loopback_dev;
954 dev_hold(dev_out);
955 if (!fl.fld_dst) {
956 fl.fld_dst =
957 fl.fld_src = dnet_select_source(dev_out, 0,
958 RT_SCOPE_HOST);
959 if (!fl.fld_dst)
960 goto out;
961 }
962 fl.oif = init_net.loopback_dev->ifindex;
963 res.type = RTN_LOCAL;
964 goto make_route;
965 }
966
967 if (decnet_debug_level & 16)
968 printk(KERN_DEBUG
969 "dn_route_output_slow: initial checks complete."
970 " dst=%o4x src=%04x oif=%d try_hard=%d\n",
971 le16_to_cpu(fl.fld_dst), le16_to_cpu(fl.fld_src),
972 fl.oif, try_hard);
973
974 /*
975 * N.B. If the kernel is compiled without router support then
976 * dn_fib_lookup() will evaluate to non-zero so this if () block
977 * will always be executed.
978 */
979 err = -ESRCH;
980 if (try_hard || (err = dn_fib_lookup(&fl, &res)) != 0) {
981 struct dn_dev *dn_db;
982 if (err != -ESRCH)
983 goto out;
984 /*
985 * Here the fallback is basically the standard algorithm for
986 * routing in endnodes which is described in the DECnet routing
987 * docs
988 *
989 * If we are not trying hard, look in neighbour cache.
990 * The result is tested to ensure that if a specific output
991 * device/source address was requested, then we honour that
992 * here
993 */
994 if (!try_hard) {
995 neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fl.fld_dst);
996 if (neigh) {
997 if ((oldflp->oif &&
998 (neigh->dev->ifindex != oldflp->oif)) ||
999 (oldflp->fld_src &&
1000 (!dn_dev_islocal(neigh->dev,
1001 oldflp->fld_src)))) {
1002 neigh_release(neigh);
1003 neigh = NULL;
1004 } else {
1005 if (dev_out)
1006 dev_put(dev_out);
1007 if (dn_dev_islocal(neigh->dev, fl.fld_dst)) {
1008 dev_out = init_net.loopback_dev;
1009 res.type = RTN_LOCAL;
1010 } else {
1011 dev_out = neigh->dev;
1012 }
1013 dev_hold(dev_out);
1014 goto select_source;
1015 }
1016 }
1017 }
1018
1019 /* Not there? Perhaps its a local address */
1020 if (dev_out == NULL)
1021 dev_out = dn_dev_get_default();
1022 err = -ENODEV;
1023 if (dev_out == NULL)
1024 goto out;
1025 dn_db = dev_out->dn_ptr;
1026 /* Possible improvement - check all devices for local addr */
1027 if (dn_dev_islocal(dev_out, fl.fld_dst)) {
1028 dev_put(dev_out);
1029 dev_out = init_net.loopback_dev;
1030 dev_hold(dev_out);
1031 res.type = RTN_LOCAL;
1032 goto select_source;
1033 }
1034 /* Not local either.... try sending it to the default router */
1035 neigh = neigh_clone(dn_db->router);
1036 BUG_ON(neigh && neigh->dev != dev_out);
1037
1038 /* Ok then, we assume its directly connected and move on */
1039 select_source:
1040 if (neigh)
1041 gateway = ((struct dn_neigh *)neigh)->addr;
1042 if (gateway == 0)
1043 gateway = fl.fld_dst;
1044 if (fl.fld_src == 0) {
1045 fl.fld_src = dnet_select_source(dev_out, gateway,
1046 res.type == RTN_LOCAL ?
1047 RT_SCOPE_HOST :
1048 RT_SCOPE_LINK);
1049 if (fl.fld_src == 0 && res.type != RTN_LOCAL)
1050 goto e_addr;
1051 }
1052 fl.oif = dev_out->ifindex;
1053 goto make_route;
1054 }
1055 free_res = 1;
1056
1057 if (res.type == RTN_NAT)
1058 goto e_inval;
1059
1060 if (res.type == RTN_LOCAL) {
1061 if (!fl.fld_src)
1062 fl.fld_src = fl.fld_dst;
1063 if (dev_out)
1064 dev_put(dev_out);
1065 dev_out = init_net.loopback_dev;
1066 dev_hold(dev_out);
1067 fl.oif = dev_out->ifindex;
1068 if (res.fi)
1069 dn_fib_info_put(res.fi);
1070 res.fi = NULL;
1071 goto make_route;
1072 }
1073
1074 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1075 dn_fib_select_multipath(&fl, &res);
1076
1077 /*
1078 * We could add some logic to deal with default routes here and
1079 * get rid of some of the special casing above.
1080 */
1081
1082 if (!fl.fld_src)
1083 fl.fld_src = DN_FIB_RES_PREFSRC(res);
1084
1085 if (dev_out)
1086 dev_put(dev_out);
1087 dev_out = DN_FIB_RES_DEV(res);
1088 dev_hold(dev_out);
1089 fl.oif = dev_out->ifindex;
1090 gateway = DN_FIB_RES_GW(res);
1091
1092 make_route:
1093 if (dev_out->flags & IFF_LOOPBACK)
1094 flags |= RTCF_LOCAL;
1095
1096 rt = dst_alloc(&dn_dst_ops);
1097 if (rt == NULL)
1098 goto e_nobufs;
1099
1100 atomic_set(&rt->u.dst.__refcnt, 1);
1101 rt->u.dst.flags = DST_HOST;
1102
1103 rt->fl.fld_src = oldflp->fld_src;
1104 rt->fl.fld_dst = oldflp->fld_dst;
1105 rt->fl.oif = oldflp->oif;
1106 rt->fl.iif = 0;
1107 rt->fl.mark = oldflp->mark;
1108
1109 rt->rt_saddr = fl.fld_src;
1110 rt->rt_daddr = fl.fld_dst;
1111 rt->rt_gateway = gateway ? gateway : fl.fld_dst;
1112 rt->rt_local_src = fl.fld_src;
1113
1114 rt->rt_dst_map = fl.fld_dst;
1115 rt->rt_src_map = fl.fld_src;
1116
1117 rt->u.dst.dev = dev_out;
1118 dev_hold(dev_out);
1119 rt->u.dst.neighbour = neigh;
1120 neigh = NULL;
1121
1122 rt->u.dst.lastuse = jiffies;
1123 rt->u.dst.output = dn_output;
1124 rt->u.dst.input = dn_rt_bug;
1125 rt->rt_flags = flags;
1126 if (flags & RTCF_LOCAL)
1127 rt->u.dst.input = dn_nsp_rx;
1128
1129 err = dn_rt_set_next_hop(rt, &res);
1130 if (err)
1131 goto e_neighbour;
1132
1133 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1134 dn_insert_route(rt, hash, (struct dn_route **)pprt);
1135
1136 done:
1137 if (neigh)
1138 neigh_release(neigh);
1139 if (free_res)
1140 dn_fib_res_put(&res);
1141 if (dev_out)
1142 dev_put(dev_out);
1143 out:
1144 return err;
1145
1146 e_addr:
1147 err = -EADDRNOTAVAIL;
1148 goto done;
1149 e_inval:
1150 err = -EINVAL;
1151 goto done;
1152 e_nobufs:
1153 err = -ENOBUFS;
1154 goto done;
1155 e_neighbour:
1156 dst_free(&rt->u.dst);
1157 goto e_nobufs;
1158 }
1159
1160
1161 /*
1162 * N.B. The flags may be moved into the flowi at some future stage.
1163 */
1164 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowi *flp, int flags)
1165 {
1166 unsigned hash = dn_hash(flp->fld_src, flp->fld_dst);
1167 struct dn_route *rt = NULL;
1168
1169 if (!(flags & MSG_TRYHARD)) {
1170 rcu_read_lock_bh();
1171 for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
1172 rt = rcu_dereference_bh(rt->u.dst.dn_next)) {
1173 if ((flp->fld_dst == rt->fl.fld_dst) &&
1174 (flp->fld_src == rt->fl.fld_src) &&
1175 (flp->mark == rt->fl.mark) &&
1176 (rt->fl.iif == 0) &&
1177 (rt->fl.oif == flp->oif)) {
1178 dst_use(&rt->u.dst, jiffies);
1179 rcu_read_unlock_bh();
1180 *pprt = &rt->u.dst;
1181 return 0;
1182 }
1183 }
1184 rcu_read_unlock_bh();
1185 }
1186
1187 return dn_route_output_slow(pprt, flp, flags);
1188 }
1189
1190 static int dn_route_output_key(struct dst_entry **pprt, struct flowi *flp, int flags)
1191 {
1192 int err;
1193
1194 err = __dn_route_output_key(pprt, flp, flags);
1195 if (err == 0 && flp->proto) {
1196 err = xfrm_lookup(&init_net, pprt, flp, NULL, 0);
1197 }
1198 return err;
1199 }
1200
1201 int dn_route_output_sock(struct dst_entry **pprt, struct flowi *fl, struct sock *sk, int flags)
1202 {
1203 int err;
1204
1205 err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1206 if (err == 0 && fl->proto) {
1207 err = xfrm_lookup(&init_net, pprt, fl, sk,
1208 (flags & MSG_DONTWAIT) ? 0 : XFRM_LOOKUP_WAIT);
1209 }
1210 return err;
1211 }
1212
1213 static int dn_route_input_slow(struct sk_buff *skb)
1214 {
1215 struct dn_route *rt = NULL;
1216 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1217 struct net_device *in_dev = skb->dev;
1218 struct net_device *out_dev = NULL;
1219 struct dn_dev *dn_db;
1220 struct neighbour *neigh = NULL;
1221 unsigned hash;
1222 int flags = 0;
1223 __le16 gateway = 0;
1224 __le16 local_src = 0;
1225 struct flowi fl = { .nl_u = { .dn_u =
1226 { .daddr = cb->dst,
1227 .saddr = cb->src,
1228 .scope = RT_SCOPE_UNIVERSE,
1229 } },
1230 .mark = skb->mark,
1231 .iif = skb->dev->ifindex };
1232 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1233 int err = -EINVAL;
1234 int free_res = 0;
1235
1236 dev_hold(in_dev);
1237
1238 if ((dn_db = in_dev->dn_ptr) == NULL)
1239 goto out;
1240
1241 /* Zero source addresses are not allowed */
1242 if (fl.fld_src == 0)
1243 goto out;
1244
1245 /*
1246 * In this case we've just received a packet from a source
1247 * outside ourselves pretending to come from us. We don't
1248 * allow it any further to prevent routing loops, spoofing and
1249 * other nasties. Loopback packets already have the dst attached
1250 * so this only affects packets which have originated elsewhere.
1251 */
1252 err = -ENOTUNIQ;
1253 if (dn_dev_islocal(in_dev, cb->src))
1254 goto out;
1255
1256 err = dn_fib_lookup(&fl, &res);
1257 if (err) {
1258 if (err != -ESRCH)
1259 goto out;
1260 /*
1261 * Is the destination us ?
1262 */
1263 if (!dn_dev_islocal(in_dev, cb->dst))
1264 goto e_inval;
1265
1266 res.type = RTN_LOCAL;
1267 } else {
1268 __le16 src_map = fl.fld_src;
1269 free_res = 1;
1270
1271 out_dev = DN_FIB_RES_DEV(res);
1272 if (out_dev == NULL) {
1273 if (net_ratelimit())
1274 printk(KERN_CRIT "Bug in dn_route_input_slow() "
1275 "No output device\n");
1276 goto e_inval;
1277 }
1278 dev_hold(out_dev);
1279
1280 if (res.r)
1281 src_map = fl.fld_src; /* no NAT support for now */
1282
1283 gateway = DN_FIB_RES_GW(res);
1284 if (res.type == RTN_NAT) {
1285 fl.fld_dst = dn_fib_rules_map_destination(fl.fld_dst, &res);
1286 dn_fib_res_put(&res);
1287 free_res = 0;
1288 if (dn_fib_lookup(&fl, &res))
1289 goto e_inval;
1290 free_res = 1;
1291 if (res.type != RTN_UNICAST)
1292 goto e_inval;
1293 flags |= RTCF_DNAT;
1294 gateway = fl.fld_dst;
1295 }
1296 fl.fld_src = src_map;
1297 }
1298
1299 switch(res.type) {
1300 case RTN_UNICAST:
1301 /*
1302 * Forwarding check here, we only check for forwarding
1303 * being turned off, if you want to only forward intra
1304 * area, its up to you to set the routing tables up
1305 * correctly.
1306 */
1307 if (dn_db->parms.forwarding == 0)
1308 goto e_inval;
1309
1310 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1311 dn_fib_select_multipath(&fl, &res);
1312
1313 /*
1314 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1315 * flag as a hint to set the intra-ethernet bit when
1316 * forwarding. If we've got NAT in operation, we don't do
1317 * this optimisation.
1318 */
1319 if (out_dev == in_dev && !(flags & RTCF_NAT))
1320 flags |= RTCF_DOREDIRECT;
1321
1322 local_src = DN_FIB_RES_PREFSRC(res);
1323
1324 case RTN_BLACKHOLE:
1325 case RTN_UNREACHABLE:
1326 break;
1327 case RTN_LOCAL:
1328 flags |= RTCF_LOCAL;
1329 fl.fld_src = cb->dst;
1330 fl.fld_dst = cb->src;
1331
1332 /* Routing tables gave us a gateway */
1333 if (gateway)
1334 goto make_route;
1335
1336 /* Packet was intra-ethernet, so we know its on-link */
1337 if (cb->rt_flags & DN_RT_F_IE) {
1338 gateway = cb->src;
1339 flags |= RTCF_DIRECTSRC;
1340 goto make_route;
1341 }
1342
1343 /* Use the default router if there is one */
1344 neigh = neigh_clone(dn_db->router);
1345 if (neigh) {
1346 gateway = ((struct dn_neigh *)neigh)->addr;
1347 goto make_route;
1348 }
1349
1350 /* Close eyes and pray */
1351 gateway = cb->src;
1352 flags |= RTCF_DIRECTSRC;
1353 goto make_route;
1354 default:
1355 goto e_inval;
1356 }
1357
1358 make_route:
1359 rt = dst_alloc(&dn_dst_ops);
1360 if (rt == NULL)
1361 goto e_nobufs;
1362
1363 rt->rt_saddr = fl.fld_src;
1364 rt->rt_daddr = fl.fld_dst;
1365 rt->rt_gateway = fl.fld_dst;
1366 if (gateway)
1367 rt->rt_gateway = gateway;
1368 rt->rt_local_src = local_src ? local_src : rt->rt_saddr;
1369
1370 rt->rt_dst_map = fl.fld_dst;
1371 rt->rt_src_map = fl.fld_src;
1372
1373 rt->fl.fld_src = cb->src;
1374 rt->fl.fld_dst = cb->dst;
1375 rt->fl.oif = 0;
1376 rt->fl.iif = in_dev->ifindex;
1377 rt->fl.mark = fl.mark;
1378
1379 rt->u.dst.flags = DST_HOST;
1380 rt->u.dst.neighbour = neigh;
1381 rt->u.dst.dev = out_dev;
1382 rt->u.dst.lastuse = jiffies;
1383 rt->u.dst.output = dn_rt_bug;
1384 switch(res.type) {
1385 case RTN_UNICAST:
1386 rt->u.dst.input = dn_forward;
1387 break;
1388 case RTN_LOCAL:
1389 rt->u.dst.output = dn_output;
1390 rt->u.dst.input = dn_nsp_rx;
1391 rt->u.dst.dev = in_dev;
1392 flags |= RTCF_LOCAL;
1393 break;
1394 default:
1395 case RTN_UNREACHABLE:
1396 case RTN_BLACKHOLE:
1397 rt->u.dst.input = dst_discard;
1398 }
1399 rt->rt_flags = flags;
1400 if (rt->u.dst.dev)
1401 dev_hold(rt->u.dst.dev);
1402
1403 err = dn_rt_set_next_hop(rt, &res);
1404 if (err)
1405 goto e_neighbour;
1406
1407 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1408 dn_insert_route(rt, hash, &rt);
1409 skb_dst_set(skb, &rt->u.dst);
1410
1411 done:
1412 if (neigh)
1413 neigh_release(neigh);
1414 if (free_res)
1415 dn_fib_res_put(&res);
1416 dev_put(in_dev);
1417 if (out_dev)
1418 dev_put(out_dev);
1419 out:
1420 return err;
1421
1422 e_inval:
1423 err = -EINVAL;
1424 goto done;
1425
1426 e_nobufs:
1427 err = -ENOBUFS;
1428 goto done;
1429
1430 e_neighbour:
1431 dst_free(&rt->u.dst);
1432 goto done;
1433 }
1434
1435 static int dn_route_input(struct sk_buff *skb)
1436 {
1437 struct dn_route *rt;
1438 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1439 unsigned hash = dn_hash(cb->src, cb->dst);
1440
1441 if (skb_dst(skb))
1442 return 0;
1443
1444 rcu_read_lock();
1445 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1446 rt = rcu_dereference(rt->u.dst.dn_next)) {
1447 if ((rt->fl.fld_src == cb->src) &&
1448 (rt->fl.fld_dst == cb->dst) &&
1449 (rt->fl.oif == 0) &&
1450 (rt->fl.mark == skb->mark) &&
1451 (rt->fl.iif == cb->iif)) {
1452 dst_use(&rt->u.dst, jiffies);
1453 rcu_read_unlock();
1454 skb_dst_set(skb, (struct dst_entry *)rt);
1455 return 0;
1456 }
1457 }
1458 rcu_read_unlock();
1459
1460 return dn_route_input_slow(skb);
1461 }
1462
1463 static int dn_rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1464 int event, int nowait, unsigned int flags)
1465 {
1466 struct dn_route *rt = (struct dn_route *)skb_dst(skb);
1467 struct rtmsg *r;
1468 struct nlmsghdr *nlh;
1469 unsigned char *b = skb_tail_pointer(skb);
1470 long expires;
1471
1472 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
1473 r = NLMSG_DATA(nlh);
1474 r->rtm_family = AF_DECnet;
1475 r->rtm_dst_len = 16;
1476 r->rtm_src_len = 0;
1477 r->rtm_tos = 0;
1478 r->rtm_table = RT_TABLE_MAIN;
1479 RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
1480 r->rtm_type = rt->rt_type;
1481 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1482 r->rtm_scope = RT_SCOPE_UNIVERSE;
1483 r->rtm_protocol = RTPROT_UNSPEC;
1484 if (rt->rt_flags & RTCF_NOTIFY)
1485 r->rtm_flags |= RTM_F_NOTIFY;
1486 RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr);
1487 if (rt->fl.fld_src) {
1488 r->rtm_src_len = 16;
1489 RTA_PUT(skb, RTA_SRC, 2, &rt->fl.fld_src);
1490 }
1491 if (rt->u.dst.dev)
1492 RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->u.dst.dev->ifindex);
1493 /*
1494 * Note to self - change this if input routes reverse direction when
1495 * they deal only with inputs and not with replies like they do
1496 * currently.
1497 */
1498 RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src);
1499 if (rt->rt_daddr != rt->rt_gateway)
1500 RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway);
1501 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
1502 goto rtattr_failure;
1503 expires = rt->u.dst.expires ? rt->u.dst.expires - jiffies : 0;
1504 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0, expires,
1505 rt->u.dst.error) < 0)
1506 goto rtattr_failure;
1507 if (rt->fl.iif)
1508 RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fl.iif);
1509
1510 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1511 return skb->len;
1512
1513 nlmsg_failure:
1514 rtattr_failure:
1515 nlmsg_trim(skb, b);
1516 return -1;
1517 }
1518
1519 /*
1520 * This is called by both endnodes and routers now.
1521 */
1522 static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
1523 {
1524 struct net *net = sock_net(in_skb->sk);
1525 struct rtattr **rta = arg;
1526 struct rtmsg *rtm = NLMSG_DATA(nlh);
1527 struct dn_route *rt = NULL;
1528 struct dn_skb_cb *cb;
1529 int err;
1530 struct sk_buff *skb;
1531 struct flowi fl;
1532
1533 if (!net_eq(net, &init_net))
1534 return -EINVAL;
1535
1536 memset(&fl, 0, sizeof(fl));
1537 fl.proto = DNPROTO_NSP;
1538
1539 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1540 if (skb == NULL)
1541 return -ENOBUFS;
1542 skb_reset_mac_header(skb);
1543 cb = DN_SKB_CB(skb);
1544
1545 if (rta[RTA_SRC-1])
1546 memcpy(&fl.fld_src, RTA_DATA(rta[RTA_SRC-1]), 2);
1547 if (rta[RTA_DST-1])
1548 memcpy(&fl.fld_dst, RTA_DATA(rta[RTA_DST-1]), 2);
1549 if (rta[RTA_IIF-1])
1550 memcpy(&fl.iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
1551
1552 if (fl.iif) {
1553 struct net_device *dev;
1554 if ((dev = dev_get_by_index(&init_net, fl.iif)) == NULL) {
1555 kfree_skb(skb);
1556 return -ENODEV;
1557 }
1558 if (!dev->dn_ptr) {
1559 dev_put(dev);
1560 kfree_skb(skb);
1561 return -ENODEV;
1562 }
1563 skb->protocol = htons(ETH_P_DNA_RT);
1564 skb->dev = dev;
1565 cb->src = fl.fld_src;
1566 cb->dst = fl.fld_dst;
1567 local_bh_disable();
1568 err = dn_route_input(skb);
1569 local_bh_enable();
1570 memset(cb, 0, sizeof(struct dn_skb_cb));
1571 rt = (struct dn_route *)skb_dst(skb);
1572 if (!err && -rt->u.dst.error)
1573 err = rt->u.dst.error;
1574 } else {
1575 int oif = 0;
1576 if (rta[RTA_OIF - 1])
1577 memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
1578 fl.oif = oif;
1579 err = dn_route_output_key((struct dst_entry **)&rt, &fl, 0);
1580 }
1581
1582 if (skb->dev)
1583 dev_put(skb->dev);
1584 skb->dev = NULL;
1585 if (err)
1586 goto out_free;
1587 skb_dst_set(skb, &rt->u.dst);
1588 if (rtm->rtm_flags & RTM_F_NOTIFY)
1589 rt->rt_flags |= RTCF_NOTIFY;
1590
1591 err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1592
1593 if (err == 0)
1594 goto out_free;
1595 if (err < 0) {
1596 err = -EMSGSIZE;
1597 goto out_free;
1598 }
1599
1600 return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).pid);
1601
1602 out_free:
1603 kfree_skb(skb);
1604 return err;
1605 }
1606
1607 /*
1608 * For routers, this is called from dn_fib_dump, but for endnodes its
1609 * called directly from the rtnetlink dispatch table.
1610 */
1611 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1612 {
1613 struct net *net = sock_net(skb->sk);
1614 struct dn_route *rt;
1615 int h, s_h;
1616 int idx, s_idx;
1617
1618 if (!net_eq(net, &init_net))
1619 return 0;
1620
1621 if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg))
1622 return -EINVAL;
1623 if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED))
1624 return 0;
1625
1626 s_h = cb->args[0];
1627 s_idx = idx = cb->args[1];
1628 for(h = 0; h <= dn_rt_hash_mask; h++) {
1629 if (h < s_h)
1630 continue;
1631 if (h > s_h)
1632 s_idx = 0;
1633 rcu_read_lock_bh();
1634 for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
1635 rt;
1636 rt = rcu_dereference_bh(rt->u.dst.dn_next), idx++) {
1637 if (idx < s_idx)
1638 continue;
1639 skb_dst_set(skb, dst_clone(&rt->u.dst));
1640 if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
1641 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1642 1, NLM_F_MULTI) <= 0) {
1643 skb_dst_drop(skb);
1644 rcu_read_unlock_bh();
1645 goto done;
1646 }
1647 skb_dst_drop(skb);
1648 }
1649 rcu_read_unlock_bh();
1650 }
1651
1652 done:
1653 cb->args[0] = h;
1654 cb->args[1] = idx;
1655 return skb->len;
1656 }
1657
1658 #ifdef CONFIG_PROC_FS
1659 struct dn_rt_cache_iter_state {
1660 int bucket;
1661 };
1662
1663 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1664 {
1665 struct dn_route *rt = NULL;
1666 struct dn_rt_cache_iter_state *s = seq->private;
1667
1668 for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1669 rcu_read_lock_bh();
1670 rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
1671 if (rt)
1672 break;
1673 rcu_read_unlock_bh();
1674 }
1675 return rt;
1676 }
1677
1678 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1679 {
1680 struct dn_rt_cache_iter_state *s = seq->private;
1681
1682 rt = rt->u.dst.dn_next;
1683 while(!rt) {
1684 rcu_read_unlock_bh();
1685 if (--s->bucket < 0)
1686 break;
1687 rcu_read_lock_bh();
1688 rt = dn_rt_hash_table[s->bucket].chain;
1689 }
1690 return rcu_dereference_bh(rt);
1691 }
1692
1693 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1694 {
1695 struct dn_route *rt = dn_rt_cache_get_first(seq);
1696
1697 if (rt) {
1698 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1699 --*pos;
1700 }
1701 return *pos ? NULL : rt;
1702 }
1703
1704 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1705 {
1706 struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1707 ++*pos;
1708 return rt;
1709 }
1710
1711 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1712 {
1713 if (v)
1714 rcu_read_unlock_bh();
1715 }
1716
1717 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1718 {
1719 struct dn_route *rt = v;
1720 char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1721
1722 seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1723 rt->u.dst.dev ? rt->u.dst.dev->name : "*",
1724 dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
1725 dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
1726 atomic_read(&rt->u.dst.__refcnt),
1727 rt->u.dst.__use,
1728 (int) dst_metric(&rt->u.dst, RTAX_RTT));
1729 return 0;
1730 }
1731
1732 static const struct seq_operations dn_rt_cache_seq_ops = {
1733 .start = dn_rt_cache_seq_start,
1734 .next = dn_rt_cache_seq_next,
1735 .stop = dn_rt_cache_seq_stop,
1736 .show = dn_rt_cache_seq_show,
1737 };
1738
1739 static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1740 {
1741 return seq_open_private(file, &dn_rt_cache_seq_ops,
1742 sizeof(struct dn_rt_cache_iter_state));
1743 }
1744
1745 static const struct file_operations dn_rt_cache_seq_fops = {
1746 .owner = THIS_MODULE,
1747 .open = dn_rt_cache_seq_open,
1748 .read = seq_read,
1749 .llseek = seq_lseek,
1750 .release = seq_release_private,
1751 };
1752
1753 #endif /* CONFIG_PROC_FS */
1754
1755 void __init dn_route_init(void)
1756 {
1757 int i, goal, order;
1758
1759 dn_dst_ops.kmem_cachep =
1760 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1761 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1762 setup_timer(&dn_route_timer, dn_dst_check_expire, 0);
1763 dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1764 add_timer(&dn_route_timer);
1765
1766 goal = totalram_pages >> (26 - PAGE_SHIFT);
1767
1768 for(order = 0; (1UL << order) < goal; order++)
1769 /* NOTHING */;
1770
1771 /*
1772 * Only want 1024 entries max, since the table is very, very unlikely
1773 * to be larger than that.
1774 */
1775 while(order && ((((1UL << order) * PAGE_SIZE) /
1776 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1777 order--;
1778
1779 do {
1780 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1781 sizeof(struct dn_rt_hash_bucket);
1782 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1783 dn_rt_hash_mask--;
1784 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1785 __get_free_pages(GFP_ATOMIC, order);
1786 } while (dn_rt_hash_table == NULL && --order > 0);
1787
1788 if (!dn_rt_hash_table)
1789 panic("Failed to allocate DECnet route cache hash table\n");
1790
1791 printk(KERN_INFO
1792 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1793 dn_rt_hash_mask,
1794 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1795
1796 dn_rt_hash_mask--;
1797 for(i = 0; i <= dn_rt_hash_mask; i++) {
1798 spin_lock_init(&dn_rt_hash_table[i].lock);
1799 dn_rt_hash_table[i].chain = NULL;
1800 }
1801
1802 dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1803
1804 proc_net_fops_create(&init_net, "decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
1805
1806 #ifdef CONFIG_DECNET_ROUTER
1807 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute, dn_fib_dump);
1808 #else
1809 rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
1810 dn_cache_dump);
1811 #endif
1812 }
1813
1814 void __exit dn_route_cleanup(void)
1815 {
1816 del_timer(&dn_route_timer);
1817 dn_run_flush(0);
1818
1819 proc_net_remove(&init_net, "decnet_cache");
1820 }
1821
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