[NET]: Do not memcmp() over pad bytes of struct flowi.
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / decnet / dn_route.c
bloba2a43d8d93fec2e37cb1c1e50044b66448e22768
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.
6 * DECnet Routing Functions (Endnode and Router)
8 * Authors: Steve Whitehouse <SteveW@ACM.org>
9 * Eduardo Marcelo Serrat <emserrat@geocities.com>
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
44 /******************************************************************************
45 (c) 1995-1998 E.M. Serrat emserrat@geocities.com
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.
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 *******************************************************************************/
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/neighbour.h>
81 #include <net/dst.h>
82 #include <net/flow.h>
83 #include <net/fib_rules.h>
84 #include <net/dn.h>
85 #include <net/dn_dev.h>
86 #include <net/dn_nsp.h>
87 #include <net/dn_route.h>
88 #include <net/dn_neigh.h>
89 #include <net/dn_fib.h>
91 struct dn_rt_hash_bucket
93 struct dn_route *chain;
94 spinlock_t lock;
95 } __attribute__((__aligned__(8)));
97 extern struct neigh_table dn_neigh_table;
100 static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
102 static const int dn_rt_min_delay = 2 * HZ;
103 static const int dn_rt_max_delay = 10 * HZ;
104 static const int dn_rt_mtu_expires = 10 * 60 * HZ;
106 static unsigned long dn_rt_deadline;
108 static int dn_dst_gc(void);
109 static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
110 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
111 static void dn_dst_link_failure(struct sk_buff *);
112 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
113 static int dn_route_input(struct sk_buff *);
114 static void dn_run_flush(unsigned long dummy);
116 static struct dn_rt_hash_bucket *dn_rt_hash_table;
117 static unsigned dn_rt_hash_mask;
119 static struct timer_list dn_route_timer;
120 static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
121 int decnet_dst_gc_interval = 2;
123 static struct dst_ops dn_dst_ops = {
124 .family = PF_DECnet,
125 .protocol = __constant_htons(ETH_P_DNA_RT),
126 .gc_thresh = 128,
127 .gc = dn_dst_gc,
128 .check = dn_dst_check,
129 .negative_advice = dn_dst_negative_advice,
130 .link_failure = dn_dst_link_failure,
131 .update_pmtu = dn_dst_update_pmtu,
132 .entry_size = sizeof(struct dn_route),
133 .entries = ATOMIC_INIT(0),
136 static __inline__ unsigned dn_hash(__le16 src, __le16 dst)
138 __u16 tmp = (__u16 __force)(src ^ dst);
139 tmp ^= (tmp >> 3);
140 tmp ^= (tmp >> 5);
141 tmp ^= (tmp >> 10);
142 return dn_rt_hash_mask & (unsigned)tmp;
145 static inline void dnrt_free(struct dn_route *rt)
147 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
150 static inline void dnrt_drop(struct dn_route *rt)
152 dst_release(&rt->u.dst);
153 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
156 static void dn_dst_check_expire(unsigned long dummy)
158 int i;
159 struct dn_route *rt, **rtp;
160 unsigned long now = jiffies;
161 unsigned long expire = 120 * HZ;
163 for(i = 0; i <= dn_rt_hash_mask; i++) {
164 rtp = &dn_rt_hash_table[i].chain;
166 spin_lock(&dn_rt_hash_table[i].lock);
167 while((rt=*rtp) != NULL) {
168 if (atomic_read(&rt->u.dst.__refcnt) ||
169 (now - rt->u.dst.lastuse) < expire) {
170 rtp = &rt->u.rt_next;
171 continue;
173 *rtp = rt->u.rt_next;
174 rt->u.rt_next = NULL;
175 dnrt_free(rt);
177 spin_unlock(&dn_rt_hash_table[i].lock);
179 if ((jiffies - now) > 0)
180 break;
183 mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ);
186 static int dn_dst_gc(void)
188 struct dn_route *rt, **rtp;
189 int i;
190 unsigned long now = jiffies;
191 unsigned long expire = 10 * HZ;
193 for(i = 0; i <= dn_rt_hash_mask; i++) {
195 spin_lock_bh(&dn_rt_hash_table[i].lock);
196 rtp = &dn_rt_hash_table[i].chain;
198 while((rt=*rtp) != NULL) {
199 if (atomic_read(&rt->u.dst.__refcnt) ||
200 (now - rt->u.dst.lastuse) < expire) {
201 rtp = &rt->u.rt_next;
202 continue;
204 *rtp = rt->u.rt_next;
205 rt->u.rt_next = NULL;
206 dnrt_drop(rt);
207 break;
209 spin_unlock_bh(&dn_rt_hash_table[i].lock);
212 return 0;
216 * The decnet standards don't impose a particular minimum mtu, what they
217 * do insist on is that the routing layer accepts a datagram of at least
218 * 230 bytes long. Here we have to subtract the routing header length from
219 * 230 to get the minimum acceptable mtu. If there is no neighbour, then we
220 * assume the worst and use a long header size.
222 * We update both the mtu and the advertised mss (i.e. the segment size we
223 * advertise to the other end).
225 static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu)
227 u32 min_mtu = 230;
228 struct dn_dev *dn = dst->neighbour ?
229 (struct dn_dev *)dst->neighbour->dev->dn_ptr : NULL;
231 if (dn && dn->use_long == 0)
232 min_mtu -= 6;
233 else
234 min_mtu -= 21;
236 if (dst->metrics[RTAX_MTU-1] > mtu && mtu >= min_mtu) {
237 if (!(dst_metric_locked(dst, RTAX_MTU))) {
238 dst->metrics[RTAX_MTU-1] = mtu;
239 dst_set_expires(dst, dn_rt_mtu_expires);
241 if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
242 u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
243 if (dst->metrics[RTAX_ADVMSS-1] > mss)
244 dst->metrics[RTAX_ADVMSS-1] = mss;
250 * When a route has been marked obsolete. (e.g. routing cache flush)
252 static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
254 return NULL;
257 static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
259 dst_release(dst);
260 return NULL;
263 static void dn_dst_link_failure(struct sk_buff *skb)
265 return;
268 static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
270 return ((fl1->nl_u.dn_u.daddr ^ fl2->nl_u.dn_u.daddr) |
271 (fl1->nl_u.dn_u.saddr ^ fl2->nl_u.dn_u.saddr) |
272 #ifdef CONFIG_IP_ROUTE_FWMARK
273 (fl1->nl_u.dn_u.fwmark ^ fl2->nl_u.dn_u.fwmark) |
274 #endif
275 (fl1->nl_u.dn_u.scope ^ fl2->nl_u.dn_u.scope) |
276 (fl1->oif ^ fl2->oif) |
277 (fl1->iif ^ fl2->iif)) == 0;
280 static int dn_insert_route(struct dn_route *rt, unsigned hash, struct dn_route **rp)
282 struct dn_route *rth, **rthp;
283 unsigned long now = jiffies;
285 rthp = &dn_rt_hash_table[hash].chain;
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.rt_next;
292 rcu_assign_pointer(rth->u.rt_next,
293 dn_rt_hash_table[hash].chain);
294 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
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);
301 dnrt_drop(rt);
302 *rp = rth;
303 return 0;
305 rthp = &rth->u.rt_next;
308 rcu_assign_pointer(rt->u.rt_next, dn_rt_hash_table[hash].chain);
309 rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
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;
319 void dn_run_flush(unsigned long dummy)
321 int i;
322 struct dn_route *rt, *next;
324 for(i = 0; i < dn_rt_hash_mask; i++) {
325 spin_lock_bh(&dn_rt_hash_table[i].lock);
327 if ((rt = xchg(&dn_rt_hash_table[i].chain, NULL)) == NULL)
328 goto nothing_to_declare;
330 for(; rt; rt=next) {
331 next = rt->u.rt_next;
332 rt->u.rt_next = NULL;
333 dst_free((struct dst_entry *)rt);
336 nothing_to_declare:
337 spin_unlock_bh(&dn_rt_hash_table[i].lock);
341 static DEFINE_SPINLOCK(dn_rt_flush_lock);
343 void dn_rt_cache_flush(int delay)
345 unsigned long now = jiffies;
346 int user_mode = !in_interrupt();
348 if (delay < 0)
349 delay = dn_rt_min_delay;
351 spin_lock_bh(&dn_rt_flush_lock);
353 if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
354 long tmo = (long)(dn_rt_deadline - now);
356 if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
357 tmo = 0;
359 if (delay > tmo)
360 delay = tmo;
363 if (delay <= 0) {
364 spin_unlock_bh(&dn_rt_flush_lock);
365 dn_run_flush(0);
366 return;
369 if (dn_rt_deadline == 0)
370 dn_rt_deadline = now + dn_rt_max_delay;
372 dn_rt_flush_timer.expires = now + delay;
373 add_timer(&dn_rt_flush_timer);
374 spin_unlock_bh(&dn_rt_flush_lock);
378 * dn_return_short - Return a short packet to its sender
379 * @skb: The packet to return
382 static int dn_return_short(struct sk_buff *skb)
384 struct dn_skb_cb *cb;
385 unsigned char *ptr;
386 __le16 *src;
387 __le16 *dst;
388 __le16 tmp;
390 /* Add back headers */
391 skb_push(skb, skb->data - skb->nh.raw);
393 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
394 return NET_RX_DROP;
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;
401 dst = (__le16 *)ptr;
402 ptr += 2;
403 src = (__le16 *)ptr;
404 ptr += 2;
405 *ptr = 0; /* Zero hop count */
407 /* Swap source and destination */
408 tmp = *src;
409 *src = *dst;
410 *dst = tmp;
412 skb->pkt_type = PACKET_OUTGOING;
413 dn_rt_finish_output(skb, NULL, NULL);
414 return NET_RX_SUCCESS;
418 * dn_return_long - Return a long packet to its sender
419 * @skb: The long format packet to return
422 static int dn_return_long(struct sk_buff *skb)
424 struct dn_skb_cb *cb;
425 unsigned char *ptr;
426 unsigned char *src_addr, *dst_addr;
427 unsigned char tmp[ETH_ALEN];
429 /* Add back all headers */
430 skb_push(skb, skb->data - skb->nh.raw);
432 if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
433 return NET_RX_DROP;
435 cb = DN_SKB_CB(skb);
436 /* Ignore packet length and point to flags */
437 ptr = skb->data + 2;
439 /* Skip padding */
440 if (*ptr & DN_RT_F_PF) {
441 char padlen = (*ptr & ~DN_RT_F_PF);
442 ptr += padlen;
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 */
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);
458 skb->pkt_type = PACKET_OUTGOING;
459 dn_rt_finish_output(skb, dst_addr, src_addr);
460 return NET_RX_SUCCESS;
464 * dn_route_rx_packet - Try and find a route for an incoming packet
465 * @skb: The packet to find a route for
467 * Returns: result of input function if route is found, error code otherwise
469 static int dn_route_rx_packet(struct sk_buff *skb)
471 struct dn_skb_cb *cb = DN_SKB_CB(skb);
472 int err;
474 if ((err = dn_route_input(skb)) == 0)
475 return dst_input(skb);
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);
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);
496 kfree_skb(skb);
497 return NET_RX_DROP;
500 static int dn_route_rx_long(struct sk_buff *skb)
502 struct dn_skb_cb *cb = DN_SKB_CB(skb);
503 unsigned char *ptr = skb->data;
505 if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
506 goto drop_it;
508 skb_pull(skb, 20);
509 skb->h.raw = skb->data;
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;
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 */
529 return NF_HOOK(PF_DECnet, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet);
531 drop_it:
532 kfree_skb(skb);
533 return NET_RX_DROP;
538 static int dn_route_rx_short(struct sk_buff *skb)
540 struct dn_skb_cb *cb = DN_SKB_CB(skb);
541 unsigned char *ptr = skb->data;
543 if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
544 goto drop_it;
546 skb_pull(skb, 5);
547 skb->h.raw = skb->data;
549 cb->dst = *(__le16 *)ptr;
550 ptr += 2;
551 cb->src = *(__le16 *)ptr;
552 ptr += 2;
553 cb->hops = *ptr & 0x3f;
555 return NF_HOOK(PF_DECnet, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet);
557 drop_it:
558 kfree_skb(skb);
559 return NET_RX_DROP;
562 static int dn_route_discard(struct sk_buff *skb)
565 * I know we drop the packet here, but thats considered success in
566 * this case
568 kfree_skb(skb);
569 return NET_RX_SUCCESS;
572 static int dn_route_ptp_hello(struct sk_buff *skb)
574 dn_dev_hello(skb);
575 dn_neigh_pointopoint_hello(skb);
576 return NET_RX_SUCCESS;
579 int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
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;
587 if (dn == NULL)
588 goto dump_it;
590 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
591 goto out;
593 if (!pskb_may_pull(skb, 3))
594 goto dump_it;
596 skb_pull(skb, 2);
598 if (len > skb->len)
599 goto dump_it;
601 skb_trim(skb, len);
603 flags = *skb->data;
605 cb = DN_SKB_CB(skb);
606 cb->stamp = jiffies;
607 cb->iif = dev->ifindex;
610 * If we have padding, remove it.
612 if (flags & DN_RT_F_PF) {
613 padlen = flags & ~DN_RT_F_PF;
614 if (!pskb_may_pull(skb, padlen + 1))
615 goto dump_it;
616 skb_pull(skb, padlen);
617 flags = *skb->data;
620 skb->nh.raw = skb->data;
623 * Weed out future version DECnet
625 if (flags & DN_RT_F_VER)
626 goto dump_it;
628 cb->rt_flags = flags;
630 if (decnet_debug_level & 1)
631 printk(KERN_DEBUG
632 "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
633 (int)flags, (dev) ? dev->name : "???", len, skb->len,
634 padlen);
636 if (flags & DN_RT_PKT_CNTL) {
637 if (unlikely(skb_linearize(skb)))
638 goto dump_it;
640 switch(flags & DN_RT_CNTL_MSK) {
641 case DN_RT_PKT_INIT:
642 dn_dev_init_pkt(skb);
643 break;
644 case DN_RT_PKT_VERI:
645 dn_dev_veri_pkt(skb);
646 break;
649 if (dn->parms.state != DN_DEV_S_RU)
650 goto dump_it;
652 switch(flags & DN_RT_CNTL_MSK) {
653 case DN_RT_PKT_HELO:
654 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_route_ptp_hello);
656 case DN_RT_PKT_L1RT:
657 case DN_RT_PKT_L2RT:
658 return NF_HOOK(PF_DECnet, NF_DN_ROUTE, skb, skb->dev, NULL, dn_route_discard);
659 case DN_RT_PKT_ERTH:
660 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_router_hello);
662 case DN_RT_PKT_EEDH:
663 return NF_HOOK(PF_DECnet, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_endnode_hello);
665 } else {
666 if (dn->parms.state != DN_DEV_S_RU)
667 goto dump_it;
669 skb_pull(skb, 1); /* Pull flags */
671 switch(flags & DN_RT_PKT_MSK) {
672 case DN_RT_PKT_LONG:
673 return dn_route_rx_long(skb);
674 case DN_RT_PKT_SHORT:
675 return dn_route_rx_short(skb);
679 dump_it:
680 kfree_skb(skb);
681 out:
682 return NET_RX_DROP;
685 static int dn_output(struct sk_buff *skb)
687 struct dst_entry *dst = skb->dst;
688 struct dn_route *rt = (struct dn_route *)dst;
689 struct net_device *dev = dst->dev;
690 struct dn_skb_cb *cb = DN_SKB_CB(skb);
691 struct neighbour *neigh;
693 int err = -EINVAL;
695 if ((neigh = dst->neighbour) == NULL)
696 goto error;
698 skb->dev = dev;
700 cb->src = rt->rt_saddr;
701 cb->dst = rt->rt_daddr;
704 * Always set the Intra-Ethernet bit on all outgoing packets
705 * originated on this node. Only valid flag from upper layers
706 * is return-to-sender-requested. Set hop count to 0 too.
708 cb->rt_flags &= ~DN_RT_F_RQR;
709 cb->rt_flags |= DN_RT_F_IE;
710 cb->hops = 0;
712 return NF_HOOK(PF_DECnet, NF_DN_LOCAL_OUT, skb, NULL, dev, neigh->output);
714 error:
715 if (net_ratelimit())
716 printk(KERN_DEBUG "dn_output: This should not happen\n");
718 kfree_skb(skb);
720 return err;
723 static int dn_forward(struct sk_buff *skb)
725 struct dn_skb_cb *cb = DN_SKB_CB(skb);
726 struct dst_entry *dst = skb->dst;
727 struct dn_dev *dn_db = dst->dev->dn_ptr;
728 struct dn_route *rt;
729 struct neighbour *neigh = dst->neighbour;
730 int header_len;
731 #ifdef CONFIG_NETFILTER
732 struct net_device *dev = skb->dev;
733 #endif
735 if (skb->pkt_type != PACKET_HOST)
736 goto drop;
738 /* Ensure that we have enough space for headers */
739 rt = (struct dn_route *)skb->dst;
740 header_len = dn_db->use_long ? 21 : 6;
741 if (skb_cow(skb, LL_RESERVED_SPACE(rt->u.dst.dev)+header_len))
742 goto drop;
745 * Hop count exceeded.
747 if (++cb->hops > 30)
748 goto drop;
750 skb->dev = rt->u.dst.dev;
753 * If packet goes out same interface it came in on, then set
754 * the Intra-Ethernet bit. This has no effect for short
755 * packets, so we don't need to test for them here.
757 cb->rt_flags &= ~DN_RT_F_IE;
758 if (rt->rt_flags & RTCF_DOREDIRECT)
759 cb->rt_flags |= DN_RT_F_IE;
761 return NF_HOOK(PF_DECnet, NF_DN_FORWARD, skb, dev, skb->dev, neigh->output);
763 drop:
764 kfree_skb(skb);
765 return NET_RX_DROP;
769 * Drop packet. This is used for endnodes and for
770 * when we should not be forwarding packets from
771 * this dest.
773 static int dn_blackhole(struct sk_buff *skb)
775 kfree_skb(skb);
776 return NET_RX_DROP;
780 * Used to catch bugs. This should never normally get
781 * called.
783 static int dn_rt_bug(struct sk_buff *skb)
785 if (net_ratelimit()) {
786 struct dn_skb_cb *cb = DN_SKB_CB(skb);
788 printk(KERN_DEBUG "dn_rt_bug: skb from:%04x to:%04x\n",
789 dn_ntohs(cb->src), dn_ntohs(cb->dst));
792 kfree_skb(skb);
794 return NET_RX_BAD;
797 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
799 struct dn_fib_info *fi = res->fi;
800 struct net_device *dev = rt->u.dst.dev;
801 struct neighbour *n;
802 unsigned mss;
804 if (fi) {
805 if (DN_FIB_RES_GW(*res) &&
806 DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
807 rt->rt_gateway = DN_FIB_RES_GW(*res);
808 memcpy(rt->u.dst.metrics, fi->fib_metrics,
809 sizeof(rt->u.dst.metrics));
811 rt->rt_type = res->type;
813 if (dev != NULL && rt->u.dst.neighbour == NULL) {
814 n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
815 if (IS_ERR(n))
816 return PTR_ERR(n);
817 rt->u.dst.neighbour = n;
820 if (rt->u.dst.metrics[RTAX_MTU-1] == 0 ||
821 rt->u.dst.metrics[RTAX_MTU-1] > rt->u.dst.dev->mtu)
822 rt->u.dst.metrics[RTAX_MTU-1] = rt->u.dst.dev->mtu;
823 mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->u.dst));
824 if (rt->u.dst.metrics[RTAX_ADVMSS-1] == 0 ||
825 rt->u.dst.metrics[RTAX_ADVMSS-1] > mss)
826 rt->u.dst.metrics[RTAX_ADVMSS-1] = mss;
827 return 0;
830 static inline int dn_match_addr(__le16 addr1, __le16 addr2)
832 __u16 tmp = dn_ntohs(addr1) ^ dn_ntohs(addr2);
833 int match = 16;
834 while(tmp) {
835 tmp >>= 1;
836 match--;
838 return match;
841 static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
843 __le16 saddr = 0;
844 struct dn_dev *dn_db = dev->dn_ptr;
845 struct dn_ifaddr *ifa;
846 int best_match = 0;
847 int ret;
849 read_lock(&dev_base_lock);
850 for(ifa = dn_db->ifa_list; ifa; ifa = ifa->ifa_next) {
851 if (ifa->ifa_scope > scope)
852 continue;
853 if (!daddr) {
854 saddr = ifa->ifa_local;
855 break;
857 ret = dn_match_addr(daddr, ifa->ifa_local);
858 if (ret > best_match)
859 saddr = ifa->ifa_local;
860 if (best_match == 0)
861 saddr = ifa->ifa_local;
863 read_unlock(&dev_base_lock);
865 return saddr;
868 static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
870 return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
873 static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
875 __le16 mask = dnet_make_mask(res->prefixlen);
876 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
879 static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *oldflp, int try_hard)
881 struct flowi fl = { .nl_u = { .dn_u =
882 { .daddr = oldflp->fld_dst,
883 .saddr = oldflp->fld_src,
884 .scope = RT_SCOPE_UNIVERSE,
885 #ifdef CONFIG_DECNET_ROUTE_FWMARK
886 .fwmark = oldflp->fld_fwmark
887 #endif
888 } },
889 .iif = loopback_dev.ifindex,
890 .oif = oldflp->oif };
891 struct dn_route *rt = NULL;
892 struct net_device *dev_out = NULL;
893 struct neighbour *neigh = NULL;
894 unsigned hash;
895 unsigned flags = 0;
896 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
897 int err;
898 int free_res = 0;
899 __le16 gateway = 0;
901 if (decnet_debug_level & 16)
902 printk(KERN_DEBUG
903 "dn_route_output_slow: dst=%04x src=%04x mark=%d"
904 " iif=%d oif=%d\n", dn_ntohs(oldflp->fld_dst),
905 dn_ntohs(oldflp->fld_src),
906 oldflp->fld_fwmark, loopback_dev.ifindex, oldflp->oif);
908 /* If we have an output interface, verify its a DECnet device */
909 if (oldflp->oif) {
910 dev_out = dev_get_by_index(oldflp->oif);
911 err = -ENODEV;
912 if (dev_out && dev_out->dn_ptr == NULL) {
913 dev_put(dev_out);
914 dev_out = NULL;
916 if (dev_out == NULL)
917 goto out;
920 /* If we have a source address, verify that its a local address */
921 if (oldflp->fld_src) {
922 err = -EADDRNOTAVAIL;
924 if (dev_out) {
925 if (dn_dev_islocal(dev_out, oldflp->fld_src))
926 goto source_ok;
927 dev_put(dev_out);
928 goto out;
930 read_lock(&dev_base_lock);
931 for(dev_out = dev_base; dev_out; dev_out = dev_out->next) {
932 if (!dev_out->dn_ptr)
933 continue;
934 if (!dn_dev_islocal(dev_out, oldflp->fld_src))
935 continue;
936 if ((dev_out->flags & IFF_LOOPBACK) &&
937 oldflp->fld_dst &&
938 !dn_dev_islocal(dev_out, oldflp->fld_dst))
939 continue;
940 break;
942 read_unlock(&dev_base_lock);
943 if (dev_out == NULL)
944 goto out;
945 dev_hold(dev_out);
946 source_ok:
950 /* No destination? Assume its local */
951 if (!fl.fld_dst) {
952 fl.fld_dst = fl.fld_src;
954 err = -EADDRNOTAVAIL;
955 if (dev_out)
956 dev_put(dev_out);
957 dev_out = &loopback_dev;
958 dev_hold(dev_out);
959 if (!fl.fld_dst) {
960 fl.fld_dst =
961 fl.fld_src = dnet_select_source(dev_out, 0,
962 RT_SCOPE_HOST);
963 if (!fl.fld_dst)
964 goto out;
966 fl.oif = loopback_dev.ifindex;
967 res.type = RTN_LOCAL;
968 goto make_route;
971 if (decnet_debug_level & 16)
972 printk(KERN_DEBUG
973 "dn_route_output_slow: initial checks complete."
974 " dst=%o4x src=%04x oif=%d try_hard=%d\n",
975 dn_ntohs(fl.fld_dst), dn_ntohs(fl.fld_src),
976 fl.oif, try_hard);
979 * N.B. If the kernel is compiled without router support then
980 * dn_fib_lookup() will evaluate to non-zero so this if () block
981 * will always be executed.
983 err = -ESRCH;
984 if (try_hard || (err = dn_fib_lookup(&fl, &res)) != 0) {
985 struct dn_dev *dn_db;
986 if (err != -ESRCH)
987 goto out;
989 * Here the fallback is basically the standard algorithm for
990 * routing in endnodes which is described in the DECnet routing
991 * docs
993 * If we are not trying hard, look in neighbour cache.
994 * The result is tested to ensure that if a specific output
995 * device/source address was requested, then we honour that
996 * here
998 if (!try_hard) {
999 neigh = neigh_lookup_nodev(&dn_neigh_table, &fl.fld_dst);
1000 if (neigh) {
1001 if ((oldflp->oif &&
1002 (neigh->dev->ifindex != oldflp->oif)) ||
1003 (oldflp->fld_src &&
1004 (!dn_dev_islocal(neigh->dev,
1005 oldflp->fld_src)))) {
1006 neigh_release(neigh);
1007 neigh = NULL;
1008 } else {
1009 if (dev_out)
1010 dev_put(dev_out);
1011 if (dn_dev_islocal(neigh->dev, fl.fld_dst)) {
1012 dev_out = &loopback_dev;
1013 res.type = RTN_LOCAL;
1014 } else {
1015 dev_out = neigh->dev;
1017 dev_hold(dev_out);
1018 goto select_source;
1023 /* Not there? Perhaps its a local address */
1024 if (dev_out == NULL)
1025 dev_out = dn_dev_get_default();
1026 err = -ENODEV;
1027 if (dev_out == NULL)
1028 goto out;
1029 dn_db = dev_out->dn_ptr;
1030 /* Possible improvement - check all devices for local addr */
1031 if (dn_dev_islocal(dev_out, fl.fld_dst)) {
1032 dev_put(dev_out);
1033 dev_out = &loopback_dev;
1034 dev_hold(dev_out);
1035 res.type = RTN_LOCAL;
1036 goto select_source;
1038 /* Not local either.... try sending it to the default router */
1039 neigh = neigh_clone(dn_db->router);
1040 BUG_ON(neigh && neigh->dev != dev_out);
1042 /* Ok then, we assume its directly connected and move on */
1043 select_source:
1044 if (neigh)
1045 gateway = ((struct dn_neigh *)neigh)->addr;
1046 if (gateway == 0)
1047 gateway = fl.fld_dst;
1048 if (fl.fld_src == 0) {
1049 fl.fld_src = dnet_select_source(dev_out, gateway,
1050 res.type == RTN_LOCAL ?
1051 RT_SCOPE_HOST :
1052 RT_SCOPE_LINK);
1053 if (fl.fld_src == 0 && res.type != RTN_LOCAL)
1054 goto e_addr;
1056 fl.oif = dev_out->ifindex;
1057 goto make_route;
1059 free_res = 1;
1061 if (res.type == RTN_NAT)
1062 goto e_inval;
1064 if (res.type == RTN_LOCAL) {
1065 if (!fl.fld_src)
1066 fl.fld_src = fl.fld_dst;
1067 if (dev_out)
1068 dev_put(dev_out);
1069 dev_out = &loopback_dev;
1070 dev_hold(dev_out);
1071 fl.oif = dev_out->ifindex;
1072 if (res.fi)
1073 dn_fib_info_put(res.fi);
1074 res.fi = NULL;
1075 goto make_route;
1078 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1079 dn_fib_select_multipath(&fl, &res);
1082 * We could add some logic to deal with default routes here and
1083 * get rid of some of the special casing above.
1086 if (!fl.fld_src)
1087 fl.fld_src = DN_FIB_RES_PREFSRC(res);
1089 if (dev_out)
1090 dev_put(dev_out);
1091 dev_out = DN_FIB_RES_DEV(res);
1092 dev_hold(dev_out);
1093 fl.oif = dev_out->ifindex;
1094 gateway = DN_FIB_RES_GW(res);
1096 make_route:
1097 if (dev_out->flags & IFF_LOOPBACK)
1098 flags |= RTCF_LOCAL;
1100 rt = dst_alloc(&dn_dst_ops);
1101 if (rt == NULL)
1102 goto e_nobufs;
1104 atomic_set(&rt->u.dst.__refcnt, 1);
1105 rt->u.dst.flags = DST_HOST;
1107 rt->fl.fld_src = oldflp->fld_src;
1108 rt->fl.fld_dst = oldflp->fld_dst;
1109 rt->fl.oif = oldflp->oif;
1110 rt->fl.iif = 0;
1111 #ifdef CONFIG_DECNET_ROUTE_FWMARK
1112 rt->fl.fld_fwmark = oldflp->fld_fwmark;
1113 #endif
1115 rt->rt_saddr = fl.fld_src;
1116 rt->rt_daddr = fl.fld_dst;
1117 rt->rt_gateway = gateway ? gateway : fl.fld_dst;
1118 rt->rt_local_src = fl.fld_src;
1120 rt->rt_dst_map = fl.fld_dst;
1121 rt->rt_src_map = fl.fld_src;
1123 rt->u.dst.dev = dev_out;
1124 dev_hold(dev_out);
1125 rt->u.dst.neighbour = neigh;
1126 neigh = NULL;
1128 rt->u.dst.lastuse = jiffies;
1129 rt->u.dst.output = dn_output;
1130 rt->u.dst.input = dn_rt_bug;
1131 rt->rt_flags = flags;
1132 if (flags & RTCF_LOCAL)
1133 rt->u.dst.input = dn_nsp_rx;
1135 err = dn_rt_set_next_hop(rt, &res);
1136 if (err)
1137 goto e_neighbour;
1139 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1140 dn_insert_route(rt, hash, (struct dn_route **)pprt);
1142 done:
1143 if (neigh)
1144 neigh_release(neigh);
1145 if (free_res)
1146 dn_fib_res_put(&res);
1147 if (dev_out)
1148 dev_put(dev_out);
1149 out:
1150 return err;
1152 e_addr:
1153 err = -EADDRNOTAVAIL;
1154 goto done;
1155 e_inval:
1156 err = -EINVAL;
1157 goto done;
1158 e_nobufs:
1159 err = -ENOBUFS;
1160 goto done;
1161 e_neighbour:
1162 dst_free(&rt->u.dst);
1163 goto e_nobufs;
1168 * N.B. The flags may be moved into the flowi at some future stage.
1170 static int __dn_route_output_key(struct dst_entry **pprt, const struct flowi *flp, int flags)
1172 unsigned hash = dn_hash(flp->fld_src, flp->fld_dst);
1173 struct dn_route *rt = NULL;
1175 if (!(flags & MSG_TRYHARD)) {
1176 rcu_read_lock_bh();
1177 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt;
1178 rt = rcu_dereference(rt->u.rt_next)) {
1179 if ((flp->fld_dst == rt->fl.fld_dst) &&
1180 (flp->fld_src == rt->fl.fld_src) &&
1181 #ifdef CONFIG_DECNET_ROUTE_FWMARK
1182 (flp->fld_fwmark == rt->fl.fld_fwmark) &&
1183 #endif
1184 (rt->fl.iif == 0) &&
1185 (rt->fl.oif == flp->oif)) {
1186 rt->u.dst.lastuse = jiffies;
1187 dst_hold(&rt->u.dst);
1188 rt->u.dst.__use++;
1189 rcu_read_unlock_bh();
1190 *pprt = &rt->u.dst;
1191 return 0;
1194 rcu_read_unlock_bh();
1197 return dn_route_output_slow(pprt, flp, flags);
1200 static int dn_route_output_key(struct dst_entry **pprt, struct flowi *flp, int flags)
1202 int err;
1204 err = __dn_route_output_key(pprt, flp, flags);
1205 if (err == 0 && flp->proto) {
1206 err = xfrm_lookup(pprt, flp, NULL, 0);
1208 return err;
1211 int dn_route_output_sock(struct dst_entry **pprt, struct flowi *fl, struct sock *sk, int flags)
1213 int err;
1215 err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
1216 if (err == 0 && fl->proto) {
1217 err = xfrm_lookup(pprt, fl, sk, !(flags & MSG_DONTWAIT));
1219 return err;
1222 static int dn_route_input_slow(struct sk_buff *skb)
1224 struct dn_route *rt = NULL;
1225 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1226 struct net_device *in_dev = skb->dev;
1227 struct net_device *out_dev = NULL;
1228 struct dn_dev *dn_db;
1229 struct neighbour *neigh = NULL;
1230 unsigned hash;
1231 int flags = 0;
1232 __le16 gateway = 0;
1233 __le16 local_src = 0;
1234 struct flowi fl = { .nl_u = { .dn_u =
1235 { .daddr = cb->dst,
1236 .saddr = cb->src,
1237 .scope = RT_SCOPE_UNIVERSE,
1238 #ifdef CONFIG_DECNET_ROUTE_FWMARK
1239 .fwmark = skb->nfmark
1240 #endif
1241 } },
1242 .iif = skb->dev->ifindex };
1243 struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
1244 int err = -EINVAL;
1245 int free_res = 0;
1247 dev_hold(in_dev);
1249 if ((dn_db = in_dev->dn_ptr) == NULL)
1250 goto out;
1252 /* Zero source addresses are not allowed */
1253 if (fl.fld_src == 0)
1254 goto out;
1257 * In this case we've just received a packet from a source
1258 * outside ourselves pretending to come from us. We don't
1259 * allow it any further to prevent routing loops, spoofing and
1260 * other nasties. Loopback packets already have the dst attached
1261 * so this only affects packets which have originated elsewhere.
1263 err = -ENOTUNIQ;
1264 if (dn_dev_islocal(in_dev, cb->src))
1265 goto out;
1267 err = dn_fib_lookup(&fl, &res);
1268 if (err) {
1269 if (err != -ESRCH)
1270 goto out;
1272 * Is the destination us ?
1274 if (!dn_dev_islocal(in_dev, cb->dst))
1275 goto e_inval;
1277 res.type = RTN_LOCAL;
1278 flags |= RTCF_DIRECTSRC;
1279 } else {
1280 __le16 src_map = fl.fld_src;
1281 free_res = 1;
1283 out_dev = DN_FIB_RES_DEV(res);
1284 if (out_dev == NULL) {
1285 if (net_ratelimit())
1286 printk(KERN_CRIT "Bug in dn_route_input_slow() "
1287 "No output device\n");
1288 goto e_inval;
1290 dev_hold(out_dev);
1292 if (res.r)
1293 src_map = fl.fld_src; /* no NAT support for now */
1295 gateway = DN_FIB_RES_GW(res);
1296 if (res.type == RTN_NAT) {
1297 fl.fld_dst = dn_fib_rules_map_destination(fl.fld_dst, &res);
1298 dn_fib_res_put(&res);
1299 free_res = 0;
1300 if (dn_fib_lookup(&fl, &res))
1301 goto e_inval;
1302 free_res = 1;
1303 if (res.type != RTN_UNICAST)
1304 goto e_inval;
1305 flags |= RTCF_DNAT;
1306 gateway = fl.fld_dst;
1308 fl.fld_src = src_map;
1311 switch(res.type) {
1312 case RTN_UNICAST:
1314 * Forwarding check here, we only check for forwarding
1315 * being turned off, if you want to only forward intra
1316 * area, its up to you to set the routing tables up
1317 * correctly.
1319 if (dn_db->parms.forwarding == 0)
1320 goto e_inval;
1322 if (res.fi->fib_nhs > 1 && fl.oif == 0)
1323 dn_fib_select_multipath(&fl, &res);
1326 * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
1327 * flag as a hint to set the intra-ethernet bit when
1328 * forwarding. If we've got NAT in operation, we don't do
1329 * this optimisation.
1331 if (out_dev == in_dev && !(flags & RTCF_NAT))
1332 flags |= RTCF_DOREDIRECT;
1334 local_src = DN_FIB_RES_PREFSRC(res);
1336 case RTN_BLACKHOLE:
1337 case RTN_UNREACHABLE:
1338 break;
1339 case RTN_LOCAL:
1340 flags |= RTCF_LOCAL;
1341 fl.fld_src = cb->dst;
1342 fl.fld_dst = cb->src;
1344 /* Routing tables gave us a gateway */
1345 if (gateway)
1346 goto make_route;
1348 /* Packet was intra-ethernet, so we know its on-link */
1349 if (cb->rt_flags | DN_RT_F_IE) {
1350 gateway = cb->src;
1351 flags |= RTCF_DIRECTSRC;
1352 goto make_route;
1355 /* Use the default router if there is one */
1356 neigh = neigh_clone(dn_db->router);
1357 if (neigh) {
1358 gateway = ((struct dn_neigh *)neigh)->addr;
1359 goto make_route;
1362 /* Close eyes and pray */
1363 gateway = cb->src;
1364 flags |= RTCF_DIRECTSRC;
1365 goto make_route;
1366 default:
1367 goto e_inval;
1370 make_route:
1371 rt = dst_alloc(&dn_dst_ops);
1372 if (rt == NULL)
1373 goto e_nobufs;
1375 rt->rt_saddr = fl.fld_src;
1376 rt->rt_daddr = fl.fld_dst;
1377 rt->rt_gateway = fl.fld_dst;
1378 if (gateway)
1379 rt->rt_gateway = gateway;
1380 rt->rt_local_src = local_src ? local_src : rt->rt_saddr;
1382 rt->rt_dst_map = fl.fld_dst;
1383 rt->rt_src_map = fl.fld_src;
1385 rt->fl.fld_src = cb->src;
1386 rt->fl.fld_dst = cb->dst;
1387 rt->fl.oif = 0;
1388 rt->fl.iif = in_dev->ifindex;
1389 rt->fl.fld_fwmark = fl.fld_fwmark;
1391 rt->u.dst.flags = DST_HOST;
1392 rt->u.dst.neighbour = neigh;
1393 rt->u.dst.dev = out_dev;
1394 rt->u.dst.lastuse = jiffies;
1395 rt->u.dst.output = dn_rt_bug;
1396 switch(res.type) {
1397 case RTN_UNICAST:
1398 rt->u.dst.input = dn_forward;
1399 break;
1400 case RTN_LOCAL:
1401 rt->u.dst.output = dn_output;
1402 rt->u.dst.input = dn_nsp_rx;
1403 rt->u.dst.dev = in_dev;
1404 flags |= RTCF_LOCAL;
1405 break;
1406 default:
1407 case RTN_UNREACHABLE:
1408 case RTN_BLACKHOLE:
1409 rt->u.dst.input = dn_blackhole;
1411 rt->rt_flags = flags;
1412 if (rt->u.dst.dev)
1413 dev_hold(rt->u.dst.dev);
1415 err = dn_rt_set_next_hop(rt, &res);
1416 if (err)
1417 goto e_neighbour;
1419 hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
1420 dn_insert_route(rt, hash, (struct dn_route **)&skb->dst);
1422 done:
1423 if (neigh)
1424 neigh_release(neigh);
1425 if (free_res)
1426 dn_fib_res_put(&res);
1427 dev_put(in_dev);
1428 if (out_dev)
1429 dev_put(out_dev);
1430 out:
1431 return err;
1433 e_inval:
1434 err = -EINVAL;
1435 goto done;
1437 e_nobufs:
1438 err = -ENOBUFS;
1439 goto done;
1441 e_neighbour:
1442 dst_free(&rt->u.dst);
1443 goto done;
1446 int dn_route_input(struct sk_buff *skb)
1448 struct dn_route *rt;
1449 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1450 unsigned hash = dn_hash(cb->src, cb->dst);
1452 if (skb->dst)
1453 return 0;
1455 rcu_read_lock();
1456 for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
1457 rt = rcu_dereference(rt->u.rt_next)) {
1458 if ((rt->fl.fld_src == cb->src) &&
1459 (rt->fl.fld_dst == cb->dst) &&
1460 (rt->fl.oif == 0) &&
1461 #ifdef CONFIG_DECNET_ROUTE_FWMARK
1462 (rt->fl.fld_fwmark == skb->nfmark) &&
1463 #endif
1464 (rt->fl.iif == cb->iif)) {
1465 rt->u.dst.lastuse = jiffies;
1466 dst_hold(&rt->u.dst);
1467 rt->u.dst.__use++;
1468 rcu_read_unlock();
1469 skb->dst = (struct dst_entry *)rt;
1470 return 0;
1473 rcu_read_unlock();
1475 return dn_route_input_slow(skb);
1478 static int dn_rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1479 int event, int nowait, unsigned int flags)
1481 struct dn_route *rt = (struct dn_route *)skb->dst;
1482 struct rtmsg *r;
1483 struct nlmsghdr *nlh;
1484 unsigned char *b = skb->tail;
1485 struct rta_cacheinfo ci;
1487 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
1488 r = NLMSG_DATA(nlh);
1489 r->rtm_family = AF_DECnet;
1490 r->rtm_dst_len = 16;
1491 r->rtm_src_len = 0;
1492 r->rtm_tos = 0;
1493 r->rtm_table = RT_TABLE_MAIN;
1494 RTA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
1495 r->rtm_type = rt->rt_type;
1496 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
1497 r->rtm_scope = RT_SCOPE_UNIVERSE;
1498 r->rtm_protocol = RTPROT_UNSPEC;
1499 if (rt->rt_flags & RTCF_NOTIFY)
1500 r->rtm_flags |= RTM_F_NOTIFY;
1501 RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr);
1502 if (rt->fl.fld_src) {
1503 r->rtm_src_len = 16;
1504 RTA_PUT(skb, RTA_SRC, 2, &rt->fl.fld_src);
1506 if (rt->u.dst.dev)
1507 RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->u.dst.dev->ifindex);
1509 * Note to self - change this if input routes reverse direction when
1510 * they deal only with inputs and not with replies like they do
1511 * currently.
1513 RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src);
1514 if (rt->rt_daddr != rt->rt_gateway)
1515 RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway);
1516 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
1517 goto rtattr_failure;
1518 ci.rta_lastuse = jiffies_to_clock_t(jiffies - rt->u.dst.lastuse);
1519 ci.rta_used = rt->u.dst.__use;
1520 ci.rta_clntref = atomic_read(&rt->u.dst.__refcnt);
1521 if (rt->u.dst.expires)
1522 ci.rta_expires = jiffies_to_clock_t(rt->u.dst.expires - jiffies);
1523 else
1524 ci.rta_expires = 0;
1525 ci.rta_error = rt->u.dst.error;
1526 ci.rta_id = ci.rta_ts = ci.rta_tsage = 0;
1527 RTA_PUT(skb, RTA_CACHEINFO, sizeof(ci), &ci);
1528 if (rt->fl.iif)
1529 RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fl.iif);
1531 nlh->nlmsg_len = skb->tail - b;
1532 return skb->len;
1534 nlmsg_failure:
1535 rtattr_failure:
1536 skb_trim(skb, b - skb->data);
1537 return -1;
1541 * This is called by both endnodes and routers now.
1543 int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
1545 struct rtattr **rta = arg;
1546 struct rtmsg *rtm = NLMSG_DATA(nlh);
1547 struct dn_route *rt = NULL;
1548 struct dn_skb_cb *cb;
1549 int err;
1550 struct sk_buff *skb;
1551 struct flowi fl;
1553 memset(&fl, 0, sizeof(fl));
1554 fl.proto = DNPROTO_NSP;
1556 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1557 if (skb == NULL)
1558 return -ENOBUFS;
1559 skb->mac.raw = skb->data;
1560 cb = DN_SKB_CB(skb);
1562 if (rta[RTA_SRC-1])
1563 memcpy(&fl.fld_src, RTA_DATA(rta[RTA_SRC-1]), 2);
1564 if (rta[RTA_DST-1])
1565 memcpy(&fl.fld_dst, RTA_DATA(rta[RTA_DST-1]), 2);
1566 if (rta[RTA_IIF-1])
1567 memcpy(&fl.iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
1569 if (fl.iif) {
1570 struct net_device *dev;
1571 if ((dev = dev_get_by_index(fl.iif)) == NULL) {
1572 kfree_skb(skb);
1573 return -ENODEV;
1575 if (!dev->dn_ptr) {
1576 dev_put(dev);
1577 kfree_skb(skb);
1578 return -ENODEV;
1580 skb->protocol = __constant_htons(ETH_P_DNA_RT);
1581 skb->dev = dev;
1582 cb->src = fl.fld_src;
1583 cb->dst = fl.fld_dst;
1584 local_bh_disable();
1585 err = dn_route_input(skb);
1586 local_bh_enable();
1587 memset(cb, 0, sizeof(struct dn_skb_cb));
1588 rt = (struct dn_route *)skb->dst;
1589 if (!err && -rt->u.dst.error)
1590 err = rt->u.dst.error;
1591 } else {
1592 int oif = 0;
1593 if (rta[RTA_OIF - 1])
1594 memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
1595 fl.oif = oif;
1596 err = dn_route_output_key((struct dst_entry **)&rt, &fl, 0);
1599 if (skb->dev)
1600 dev_put(skb->dev);
1601 skb->dev = NULL;
1602 if (err)
1603 goto out_free;
1604 skb->dst = &rt->u.dst;
1605 if (rtm->rtm_flags & RTM_F_NOTIFY)
1606 rt->rt_flags |= RTCF_NOTIFY;
1608 NETLINK_CB(skb).dst_pid = NETLINK_CB(in_skb).pid;
1610 err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
1612 if (err == 0)
1613 goto out_free;
1614 if (err < 0) {
1615 err = -EMSGSIZE;
1616 goto out_free;
1619 return rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
1621 out_free:
1622 kfree_skb(skb);
1623 return err;
1627 * For routers, this is called from dn_fib_dump, but for endnodes its
1628 * called directly from the rtnetlink dispatch table.
1630 int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
1632 struct dn_route *rt;
1633 int h, s_h;
1634 int idx, s_idx;
1636 if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg))
1637 return -EINVAL;
1638 if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED))
1639 return 0;
1641 s_h = cb->args[0];
1642 s_idx = idx = cb->args[1];
1643 for(h = 0; h <= dn_rt_hash_mask; h++) {
1644 if (h < s_h)
1645 continue;
1646 if (h > s_h)
1647 s_idx = 0;
1648 rcu_read_lock_bh();
1649 for(rt = rcu_dereference(dn_rt_hash_table[h].chain), idx = 0;
1651 rt = rcu_dereference(rt->u.rt_next), idx++) {
1652 if (idx < s_idx)
1653 continue;
1654 skb->dst = dst_clone(&rt->u.dst);
1655 if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
1656 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1657 1, NLM_F_MULTI) <= 0) {
1658 dst_release(xchg(&skb->dst, NULL));
1659 rcu_read_unlock_bh();
1660 goto done;
1662 dst_release(xchg(&skb->dst, NULL));
1664 rcu_read_unlock_bh();
1667 done:
1668 cb->args[0] = h;
1669 cb->args[1] = idx;
1670 return skb->len;
1673 #ifdef CONFIG_PROC_FS
1674 struct dn_rt_cache_iter_state {
1675 int bucket;
1678 static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
1680 struct dn_route *rt = NULL;
1681 struct dn_rt_cache_iter_state *s = seq->private;
1683 for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
1684 rcu_read_lock_bh();
1685 rt = dn_rt_hash_table[s->bucket].chain;
1686 if (rt)
1687 break;
1688 rcu_read_unlock_bh();
1690 return rt;
1693 static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
1695 struct dn_rt_cache_iter_state *s = rcu_dereference(seq->private);
1697 rt = rt->u.rt_next;
1698 while(!rt) {
1699 rcu_read_unlock_bh();
1700 if (--s->bucket < 0)
1701 break;
1702 rcu_read_lock_bh();
1703 rt = dn_rt_hash_table[s->bucket].chain;
1705 return rt;
1708 static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
1710 struct dn_route *rt = dn_rt_cache_get_first(seq);
1712 if (rt) {
1713 while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
1714 --*pos;
1716 return *pos ? NULL : rt;
1719 static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1721 struct dn_route *rt = dn_rt_cache_get_next(seq, v);
1722 ++*pos;
1723 return rt;
1726 static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
1728 if (v)
1729 rcu_read_unlock_bh();
1732 static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
1734 struct dn_route *rt = v;
1735 char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
1737 seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
1738 rt->u.dst.dev ? rt->u.dst.dev->name : "*",
1739 dn_addr2asc(dn_ntohs(rt->rt_daddr), buf1),
1740 dn_addr2asc(dn_ntohs(rt->rt_saddr), buf2),
1741 atomic_read(&rt->u.dst.__refcnt),
1742 rt->u.dst.__use,
1743 (int) dst_metric(&rt->u.dst, RTAX_RTT));
1744 return 0;
1747 static struct seq_operations dn_rt_cache_seq_ops = {
1748 .start = dn_rt_cache_seq_start,
1749 .next = dn_rt_cache_seq_next,
1750 .stop = dn_rt_cache_seq_stop,
1751 .show = dn_rt_cache_seq_show,
1754 static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
1756 struct seq_file *seq;
1757 int rc = -ENOMEM;
1758 struct dn_rt_cache_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
1760 if (!s)
1761 goto out;
1762 rc = seq_open(file, &dn_rt_cache_seq_ops);
1763 if (rc)
1764 goto out_kfree;
1765 seq = file->private_data;
1766 seq->private = s;
1767 memset(s, 0, sizeof(*s));
1768 out:
1769 return rc;
1770 out_kfree:
1771 kfree(s);
1772 goto out;
1775 static struct file_operations dn_rt_cache_seq_fops = {
1776 .owner = THIS_MODULE,
1777 .open = dn_rt_cache_seq_open,
1778 .read = seq_read,
1779 .llseek = seq_lseek,
1780 .release = seq_release_private,
1783 #endif /* CONFIG_PROC_FS */
1785 void __init dn_route_init(void)
1787 int i, goal, order;
1789 dn_dst_ops.kmem_cachep =
1790 kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
1791 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
1792 init_timer(&dn_route_timer);
1793 dn_route_timer.function = dn_dst_check_expire;
1794 dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
1795 add_timer(&dn_route_timer);
1797 goal = num_physpages >> (26 - PAGE_SHIFT);
1799 for(order = 0; (1UL << order) < goal; order++)
1800 /* NOTHING */;
1803 * Only want 1024 entries max, since the table is very, very unlikely
1804 * to be larger than that.
1806 while(order && ((((1UL << order) * PAGE_SIZE) /
1807 sizeof(struct dn_rt_hash_bucket)) >= 2048))
1808 order--;
1810 do {
1811 dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
1812 sizeof(struct dn_rt_hash_bucket);
1813 while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
1814 dn_rt_hash_mask--;
1815 dn_rt_hash_table = (struct dn_rt_hash_bucket *)
1816 __get_free_pages(GFP_ATOMIC, order);
1817 } while (dn_rt_hash_table == NULL && --order > 0);
1819 if (!dn_rt_hash_table)
1820 panic("Failed to allocate DECnet route cache hash table\n");
1822 printk(KERN_INFO
1823 "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
1824 dn_rt_hash_mask,
1825 (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
1827 dn_rt_hash_mask--;
1828 for(i = 0; i <= dn_rt_hash_mask; i++) {
1829 spin_lock_init(&dn_rt_hash_table[i].lock);
1830 dn_rt_hash_table[i].chain = NULL;
1833 dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
1835 proc_net_fops_create("decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
1838 void __exit dn_route_cleanup(void)
1840 del_timer(&dn_route_timer);
1841 dn_run_flush(0);
1843 proc_net_remove("decnet_cache");