x86: cpa: convert ioremap to new API
[firewire-audio.git] / net / ipv6 / route.c
blob4004c5f0b8d78eec1ad2ae6fbd2a3494645dac5c
1 /*
2 * Linux INET6 implementation
3 * FIB front-end.
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
8 * $Id: route.c,v 1.56 2001/10/31 21:55:55 davem Exp $
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
16 /* Changes:
18 * YOSHIFUJI Hideaki @USAGI
19 * reworked default router selection.
20 * - respect outgoing interface
21 * - select from (probably) reachable routers (i.e.
22 * routers in REACHABLE, STALE, DELAY or PROBE states).
23 * - always select the same router if it is (probably)
24 * reachable. otherwise, round-robin the list.
25 * Ville Nuorvala
26 * Fixed routing subtrees.
29 #include <linux/capability.h>
30 #include <linux/errno.h>
31 #include <linux/types.h>
32 #include <linux/times.h>
33 #include <linux/socket.h>
34 #include <linux/sockios.h>
35 #include <linux/net.h>
36 #include <linux/route.h>
37 #include <linux/netdevice.h>
38 #include <linux/in6.h>
39 #include <linux/init.h>
40 #include <linux/if_arp.h>
41 #include <linux/proc_fs.h>
42 #include <linux/seq_file.h>
43 #include <net/net_namespace.h>
44 #include <net/snmp.h>
45 #include <net/ipv6.h>
46 #include <net/ip6_fib.h>
47 #include <net/ip6_route.h>
48 #include <net/ndisc.h>
49 #include <net/addrconf.h>
50 #include <net/tcp.h>
51 #include <linux/rtnetlink.h>
52 #include <net/dst.h>
53 #include <net/xfrm.h>
54 #include <net/netevent.h>
55 #include <net/netlink.h>
57 #include <asm/uaccess.h>
59 #ifdef CONFIG_SYSCTL
60 #include <linux/sysctl.h>
61 #endif
63 /* Set to 3 to get tracing. */
64 #define RT6_DEBUG 2
66 #if RT6_DEBUG >= 3
67 #define RDBG(x) printk x
68 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
69 #else
70 #define RDBG(x)
71 #define RT6_TRACE(x...) do { ; } while (0)
72 #endif
74 #define CLONE_OFFLINK_ROUTE 0
76 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
77 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
78 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
79 static void ip6_dst_destroy(struct dst_entry *);
80 static void ip6_dst_ifdown(struct dst_entry *,
81 struct net_device *dev, int how);
82 static int ip6_dst_gc(struct dst_ops *ops);
84 static int ip6_pkt_discard(struct sk_buff *skb);
85 static int ip6_pkt_discard_out(struct sk_buff *skb);
86 static void ip6_link_failure(struct sk_buff *skb);
87 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
89 #ifdef CONFIG_IPV6_ROUTE_INFO
90 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
91 struct in6_addr *gwaddr, int ifindex,
92 unsigned pref);
93 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
94 struct in6_addr *gwaddr, int ifindex);
95 #endif
97 static struct dst_ops ip6_dst_ops = {
98 .family = AF_INET6,
99 .protocol = __constant_htons(ETH_P_IPV6),
100 .gc = ip6_dst_gc,
101 .gc_thresh = 1024,
102 .check = ip6_dst_check,
103 .destroy = ip6_dst_destroy,
104 .ifdown = ip6_dst_ifdown,
105 .negative_advice = ip6_negative_advice,
106 .link_failure = ip6_link_failure,
107 .update_pmtu = ip6_rt_update_pmtu,
108 .local_out = ip6_local_out,
109 .entry_size = sizeof(struct rt6_info),
112 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
116 static struct dst_ops ip6_dst_blackhole_ops = {
117 .family = AF_INET6,
118 .protocol = __constant_htons(ETH_P_IPV6),
119 .destroy = ip6_dst_destroy,
120 .check = ip6_dst_check,
121 .update_pmtu = ip6_rt_blackhole_update_pmtu,
122 .entry_size = sizeof(struct rt6_info),
125 struct rt6_info ip6_null_entry = {
126 .u = {
127 .dst = {
128 .__refcnt = ATOMIC_INIT(1),
129 .__use = 1,
130 .obsolete = -1,
131 .error = -ENETUNREACH,
132 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
133 .input = ip6_pkt_discard,
134 .output = ip6_pkt_discard_out,
135 .ops = &ip6_dst_ops,
136 .path = (struct dst_entry*)&ip6_null_entry,
139 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
140 .rt6i_metric = ~(u32) 0,
141 .rt6i_ref = ATOMIC_INIT(1),
144 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
146 static int ip6_pkt_prohibit(struct sk_buff *skb);
147 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
149 struct rt6_info ip6_prohibit_entry = {
150 .u = {
151 .dst = {
152 .__refcnt = ATOMIC_INIT(1),
153 .__use = 1,
154 .obsolete = -1,
155 .error = -EACCES,
156 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
157 .input = ip6_pkt_prohibit,
158 .output = ip6_pkt_prohibit_out,
159 .ops = &ip6_dst_ops,
160 .path = (struct dst_entry*)&ip6_prohibit_entry,
163 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
164 .rt6i_metric = ~(u32) 0,
165 .rt6i_ref = ATOMIC_INIT(1),
168 struct rt6_info ip6_blk_hole_entry = {
169 .u = {
170 .dst = {
171 .__refcnt = ATOMIC_INIT(1),
172 .__use = 1,
173 .obsolete = -1,
174 .error = -EINVAL,
175 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
176 .input = dst_discard,
177 .output = dst_discard,
178 .ops = &ip6_dst_ops,
179 .path = (struct dst_entry*)&ip6_blk_hole_entry,
182 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
183 .rt6i_metric = ~(u32) 0,
184 .rt6i_ref = ATOMIC_INIT(1),
187 #endif
189 /* allocate dst with ip6_dst_ops */
190 static __inline__ struct rt6_info *ip6_dst_alloc(void)
192 return (struct rt6_info *)dst_alloc(&ip6_dst_ops);
195 static void ip6_dst_destroy(struct dst_entry *dst)
197 struct rt6_info *rt = (struct rt6_info *)dst;
198 struct inet6_dev *idev = rt->rt6i_idev;
200 if (idev != NULL) {
201 rt->rt6i_idev = NULL;
202 in6_dev_put(idev);
206 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
207 int how)
209 struct rt6_info *rt = (struct rt6_info *)dst;
210 struct inet6_dev *idev = rt->rt6i_idev;
211 struct net_device *loopback_dev =
212 dev->nd_net->loopback_dev;
214 if (dev != loopback_dev && idev != NULL && idev->dev == dev) {
215 struct inet6_dev *loopback_idev =
216 in6_dev_get(loopback_dev);
217 if (loopback_idev != NULL) {
218 rt->rt6i_idev = loopback_idev;
219 in6_dev_put(idev);
224 static __inline__ int rt6_check_expired(const struct rt6_info *rt)
226 return (rt->rt6i_flags & RTF_EXPIRES &&
227 time_after(jiffies, rt->rt6i_expires));
230 static inline int rt6_need_strict(struct in6_addr *daddr)
232 return (ipv6_addr_type(daddr) &
233 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
237 * Route lookup. Any table->tb6_lock is implied.
240 static __inline__ struct rt6_info *rt6_device_match(struct rt6_info *rt,
241 int oif,
242 int strict)
244 struct rt6_info *local = NULL;
245 struct rt6_info *sprt;
247 if (oif) {
248 for (sprt = rt; sprt; sprt = sprt->u.dst.rt6_next) {
249 struct net_device *dev = sprt->rt6i_dev;
250 if (dev->ifindex == oif)
251 return sprt;
252 if (dev->flags & IFF_LOOPBACK) {
253 if (sprt->rt6i_idev == NULL ||
254 sprt->rt6i_idev->dev->ifindex != oif) {
255 if (strict && oif)
256 continue;
257 if (local && (!oif ||
258 local->rt6i_idev->dev->ifindex == oif))
259 continue;
261 local = sprt;
265 if (local)
266 return local;
268 if (strict)
269 return &ip6_null_entry;
271 return rt;
274 #ifdef CONFIG_IPV6_ROUTER_PREF
275 static void rt6_probe(struct rt6_info *rt)
277 struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
279 * Okay, this does not seem to be appropriate
280 * for now, however, we need to check if it
281 * is really so; aka Router Reachability Probing.
283 * Router Reachability Probe MUST be rate-limited
284 * to no more than one per minute.
286 if (!neigh || (neigh->nud_state & NUD_VALID))
287 return;
288 read_lock_bh(&neigh->lock);
289 if (!(neigh->nud_state & NUD_VALID) &&
290 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
291 struct in6_addr mcaddr;
292 struct in6_addr *target;
294 neigh->updated = jiffies;
295 read_unlock_bh(&neigh->lock);
297 target = (struct in6_addr *)&neigh->primary_key;
298 addrconf_addr_solict_mult(target, &mcaddr);
299 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
300 } else
301 read_unlock_bh(&neigh->lock);
303 #else
304 static inline void rt6_probe(struct rt6_info *rt)
306 return;
308 #endif
311 * Default Router Selection (RFC 2461 6.3.6)
313 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
315 struct net_device *dev = rt->rt6i_dev;
316 if (!oif || dev->ifindex == oif)
317 return 2;
318 if ((dev->flags & IFF_LOOPBACK) &&
319 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
320 return 1;
321 return 0;
324 static inline int rt6_check_neigh(struct rt6_info *rt)
326 struct neighbour *neigh = rt->rt6i_nexthop;
327 int m;
328 if (rt->rt6i_flags & RTF_NONEXTHOP ||
329 !(rt->rt6i_flags & RTF_GATEWAY))
330 m = 1;
331 else if (neigh) {
332 read_lock_bh(&neigh->lock);
333 if (neigh->nud_state & NUD_VALID)
334 m = 2;
335 #ifdef CONFIG_IPV6_ROUTER_PREF
336 else if (neigh->nud_state & NUD_FAILED)
337 m = 0;
338 #endif
339 else
340 m = 1;
341 read_unlock_bh(&neigh->lock);
342 } else
343 m = 0;
344 return m;
347 static int rt6_score_route(struct rt6_info *rt, int oif,
348 int strict)
350 int m, n;
352 m = rt6_check_dev(rt, oif);
353 if (!m && (strict & RT6_LOOKUP_F_IFACE))
354 return -1;
355 #ifdef CONFIG_IPV6_ROUTER_PREF
356 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
357 #endif
358 n = rt6_check_neigh(rt);
359 if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
360 return -1;
361 return m;
364 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
365 int *mpri, struct rt6_info *match)
367 int m;
369 if (rt6_check_expired(rt))
370 goto out;
372 m = rt6_score_route(rt, oif, strict);
373 if (m < 0)
374 goto out;
376 if (m > *mpri) {
377 if (strict & RT6_LOOKUP_F_REACHABLE)
378 rt6_probe(match);
379 *mpri = m;
380 match = rt;
381 } else if (strict & RT6_LOOKUP_F_REACHABLE) {
382 rt6_probe(rt);
385 out:
386 return match;
389 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
390 struct rt6_info *rr_head,
391 u32 metric, int oif, int strict)
393 struct rt6_info *rt, *match;
394 int mpri = -1;
396 match = NULL;
397 for (rt = rr_head; rt && rt->rt6i_metric == metric;
398 rt = rt->u.dst.rt6_next)
399 match = find_match(rt, oif, strict, &mpri, match);
400 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
401 rt = rt->u.dst.rt6_next)
402 match = find_match(rt, oif, strict, &mpri, match);
404 return match;
407 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
409 struct rt6_info *match, *rt0;
411 RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
412 __FUNCTION__, fn->leaf, oif);
414 rt0 = fn->rr_ptr;
415 if (!rt0)
416 fn->rr_ptr = rt0 = fn->leaf;
418 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
420 if (!match &&
421 (strict & RT6_LOOKUP_F_REACHABLE)) {
422 struct rt6_info *next = rt0->u.dst.rt6_next;
424 /* no entries matched; do round-robin */
425 if (!next || next->rt6i_metric != rt0->rt6i_metric)
426 next = fn->leaf;
428 if (next != rt0)
429 fn->rr_ptr = next;
432 RT6_TRACE("%s() => %p\n",
433 __FUNCTION__, match);
435 return (match ? match : &ip6_null_entry);
438 #ifdef CONFIG_IPV6_ROUTE_INFO
439 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
440 struct in6_addr *gwaddr)
442 struct route_info *rinfo = (struct route_info *) opt;
443 struct in6_addr prefix_buf, *prefix;
444 unsigned int pref;
445 u32 lifetime;
446 struct rt6_info *rt;
448 if (len < sizeof(struct route_info)) {
449 return -EINVAL;
452 /* Sanity check for prefix_len and length */
453 if (rinfo->length > 3) {
454 return -EINVAL;
455 } else if (rinfo->prefix_len > 128) {
456 return -EINVAL;
457 } else if (rinfo->prefix_len > 64) {
458 if (rinfo->length < 2) {
459 return -EINVAL;
461 } else if (rinfo->prefix_len > 0) {
462 if (rinfo->length < 1) {
463 return -EINVAL;
467 pref = rinfo->route_pref;
468 if (pref == ICMPV6_ROUTER_PREF_INVALID)
469 pref = ICMPV6_ROUTER_PREF_MEDIUM;
471 lifetime = ntohl(rinfo->lifetime);
472 if (lifetime == 0xffffffff) {
473 /* infinity */
474 } else if (lifetime > 0x7fffffff/HZ) {
475 /* Avoid arithmetic overflow */
476 lifetime = 0x7fffffff/HZ - 1;
479 if (rinfo->length == 3)
480 prefix = (struct in6_addr *)rinfo->prefix;
481 else {
482 /* this function is safe */
483 ipv6_addr_prefix(&prefix_buf,
484 (struct in6_addr *)rinfo->prefix,
485 rinfo->prefix_len);
486 prefix = &prefix_buf;
489 rt = rt6_get_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex);
491 if (rt && !lifetime) {
492 ip6_del_rt(rt);
493 rt = NULL;
496 if (!rt && lifetime)
497 rt = rt6_add_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
498 pref);
499 else if (rt)
500 rt->rt6i_flags = RTF_ROUTEINFO |
501 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
503 if (rt) {
504 if (lifetime == 0xffffffff) {
505 rt->rt6i_flags &= ~RTF_EXPIRES;
506 } else {
507 rt->rt6i_expires = jiffies + HZ * lifetime;
508 rt->rt6i_flags |= RTF_EXPIRES;
510 dst_release(&rt->u.dst);
512 return 0;
514 #endif
516 #define BACKTRACK(saddr) \
517 do { \
518 if (rt == &ip6_null_entry) { \
519 struct fib6_node *pn; \
520 while (1) { \
521 if (fn->fn_flags & RTN_TL_ROOT) \
522 goto out; \
523 pn = fn->parent; \
524 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
525 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
526 else \
527 fn = pn; \
528 if (fn->fn_flags & RTN_RTINFO) \
529 goto restart; \
532 } while(0)
534 static struct rt6_info *ip6_pol_route_lookup(struct fib6_table *table,
535 struct flowi *fl, int flags)
537 struct fib6_node *fn;
538 struct rt6_info *rt;
540 read_lock_bh(&table->tb6_lock);
541 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
542 restart:
543 rt = fn->leaf;
544 rt = rt6_device_match(rt, fl->oif, flags);
545 BACKTRACK(&fl->fl6_src);
546 out:
547 dst_use(&rt->u.dst, jiffies);
548 read_unlock_bh(&table->tb6_lock);
549 return rt;
553 struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr,
554 int oif, int strict)
556 struct flowi fl = {
557 .oif = oif,
558 .nl_u = {
559 .ip6_u = {
560 .daddr = *daddr,
564 struct dst_entry *dst;
565 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
567 if (saddr) {
568 memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
569 flags |= RT6_LOOKUP_F_HAS_SADDR;
572 dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_lookup);
573 if (dst->error == 0)
574 return (struct rt6_info *) dst;
576 dst_release(dst);
578 return NULL;
581 EXPORT_SYMBOL(rt6_lookup);
583 /* ip6_ins_rt is called with FREE table->tb6_lock.
584 It takes new route entry, the addition fails by any reason the
585 route is freed. In any case, if caller does not hold it, it may
586 be destroyed.
589 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
591 int err;
592 struct fib6_table *table;
594 table = rt->rt6i_table;
595 write_lock_bh(&table->tb6_lock);
596 err = fib6_add(&table->tb6_root, rt, info);
597 write_unlock_bh(&table->tb6_lock);
599 return err;
602 int ip6_ins_rt(struct rt6_info *rt)
604 struct nl_info info = {
605 .nl_net = &init_net,
607 return __ip6_ins_rt(rt, &info);
610 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
611 struct in6_addr *saddr)
613 struct rt6_info *rt;
616 * Clone the route.
619 rt = ip6_rt_copy(ort);
621 if (rt) {
622 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
623 if (rt->rt6i_dst.plen != 128 &&
624 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
625 rt->rt6i_flags |= RTF_ANYCAST;
626 ipv6_addr_copy(&rt->rt6i_gateway, daddr);
629 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
630 rt->rt6i_dst.plen = 128;
631 rt->rt6i_flags |= RTF_CACHE;
632 rt->u.dst.flags |= DST_HOST;
634 #ifdef CONFIG_IPV6_SUBTREES
635 if (rt->rt6i_src.plen && saddr) {
636 ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
637 rt->rt6i_src.plen = 128;
639 #endif
641 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
645 return rt;
648 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
650 struct rt6_info *rt = ip6_rt_copy(ort);
651 if (rt) {
652 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
653 rt->rt6i_dst.plen = 128;
654 rt->rt6i_flags |= RTF_CACHE;
655 rt->u.dst.flags |= DST_HOST;
656 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
658 return rt;
661 static struct rt6_info *ip6_pol_route(struct fib6_table *table, int oif,
662 struct flowi *fl, int flags)
664 struct fib6_node *fn;
665 struct rt6_info *rt, *nrt;
666 int strict = 0;
667 int attempts = 3;
668 int err;
669 int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
671 strict |= flags & RT6_LOOKUP_F_IFACE;
673 relookup:
674 read_lock_bh(&table->tb6_lock);
676 restart_2:
677 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
679 restart:
680 rt = rt6_select(fn, oif, strict | reachable);
681 BACKTRACK(&fl->fl6_src);
682 if (rt == &ip6_null_entry ||
683 rt->rt6i_flags & RTF_CACHE)
684 goto out;
686 dst_hold(&rt->u.dst);
687 read_unlock_bh(&table->tb6_lock);
689 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
690 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
691 else {
692 #if CLONE_OFFLINK_ROUTE
693 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
694 #else
695 goto out2;
696 #endif
699 dst_release(&rt->u.dst);
700 rt = nrt ? : &ip6_null_entry;
702 dst_hold(&rt->u.dst);
703 if (nrt) {
704 err = ip6_ins_rt(nrt);
705 if (!err)
706 goto out2;
709 if (--attempts <= 0)
710 goto out2;
713 * Race condition! In the gap, when table->tb6_lock was
714 * released someone could insert this route. Relookup.
716 dst_release(&rt->u.dst);
717 goto relookup;
719 out:
720 if (reachable) {
721 reachable = 0;
722 goto restart_2;
724 dst_hold(&rt->u.dst);
725 read_unlock_bh(&table->tb6_lock);
726 out2:
727 rt->u.dst.lastuse = jiffies;
728 rt->u.dst.__use++;
730 return rt;
733 static struct rt6_info *ip6_pol_route_input(struct fib6_table *table,
734 struct flowi *fl, int flags)
736 return ip6_pol_route(table, fl->iif, fl, flags);
739 void ip6_route_input(struct sk_buff *skb)
741 struct ipv6hdr *iph = ipv6_hdr(skb);
742 int flags = RT6_LOOKUP_F_HAS_SADDR;
743 struct flowi fl = {
744 .iif = skb->dev->ifindex,
745 .nl_u = {
746 .ip6_u = {
747 .daddr = iph->daddr,
748 .saddr = iph->saddr,
749 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
752 .mark = skb->mark,
753 .proto = iph->nexthdr,
756 if (rt6_need_strict(&iph->daddr))
757 flags |= RT6_LOOKUP_F_IFACE;
759 skb->dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_input);
762 static struct rt6_info *ip6_pol_route_output(struct fib6_table *table,
763 struct flowi *fl, int flags)
765 return ip6_pol_route(table, fl->oif, fl, flags);
768 struct dst_entry * ip6_route_output(struct sock *sk, struct flowi *fl)
770 int flags = 0;
772 if (rt6_need_strict(&fl->fl6_dst))
773 flags |= RT6_LOOKUP_F_IFACE;
775 if (!ipv6_addr_any(&fl->fl6_src))
776 flags |= RT6_LOOKUP_F_HAS_SADDR;
778 return fib6_rule_lookup(fl, flags, ip6_pol_route_output);
781 EXPORT_SYMBOL(ip6_route_output);
783 int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl)
785 struct rt6_info *ort = (struct rt6_info *) *dstp;
786 struct rt6_info *rt = (struct rt6_info *)
787 dst_alloc(&ip6_dst_blackhole_ops);
788 struct dst_entry *new = NULL;
790 if (rt) {
791 new = &rt->u.dst;
793 atomic_set(&new->__refcnt, 1);
794 new->__use = 1;
795 new->input = dst_discard;
796 new->output = dst_discard;
798 memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
799 new->dev = ort->u.dst.dev;
800 if (new->dev)
801 dev_hold(new->dev);
802 rt->rt6i_idev = ort->rt6i_idev;
803 if (rt->rt6i_idev)
804 in6_dev_hold(rt->rt6i_idev);
805 rt->rt6i_expires = 0;
807 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
808 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
809 rt->rt6i_metric = 0;
811 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
812 #ifdef CONFIG_IPV6_SUBTREES
813 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
814 #endif
816 dst_free(new);
819 dst_release(*dstp);
820 *dstp = new;
821 return (new ? 0 : -ENOMEM);
823 EXPORT_SYMBOL_GPL(ip6_dst_blackhole);
826 * Destination cache support functions
829 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
831 struct rt6_info *rt;
833 rt = (struct rt6_info *) dst;
835 if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
836 return dst;
838 return NULL;
841 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
843 struct rt6_info *rt = (struct rt6_info *) dst;
845 if (rt) {
846 if (rt->rt6i_flags & RTF_CACHE)
847 ip6_del_rt(rt);
848 else
849 dst_release(dst);
851 return NULL;
854 static void ip6_link_failure(struct sk_buff *skb)
856 struct rt6_info *rt;
858 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev);
860 rt = (struct rt6_info *) skb->dst;
861 if (rt) {
862 if (rt->rt6i_flags&RTF_CACHE) {
863 dst_set_expires(&rt->u.dst, 0);
864 rt->rt6i_flags |= RTF_EXPIRES;
865 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
866 rt->rt6i_node->fn_sernum = -1;
870 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
872 struct rt6_info *rt6 = (struct rt6_info*)dst;
874 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
875 rt6->rt6i_flags |= RTF_MODIFIED;
876 if (mtu < IPV6_MIN_MTU) {
877 mtu = IPV6_MIN_MTU;
878 dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
880 dst->metrics[RTAX_MTU-1] = mtu;
881 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
885 static int ipv6_get_mtu(struct net_device *dev);
887 static inline unsigned int ipv6_advmss(unsigned int mtu)
889 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
891 if (mtu < init_net.ipv6.sysctl.ip6_rt_min_advmss)
892 mtu = init_net.ipv6.sysctl.ip6_rt_min_advmss;
895 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
896 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
897 * IPV6_MAXPLEN is also valid and means: "any MSS,
898 * rely only on pmtu discovery"
900 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
901 mtu = IPV6_MAXPLEN;
902 return mtu;
905 static struct dst_entry *ndisc_dst_gc_list;
906 static DEFINE_SPINLOCK(ndisc_lock);
908 struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
909 struct neighbour *neigh,
910 struct in6_addr *addr,
911 int (*output)(struct sk_buff *))
913 struct rt6_info *rt;
914 struct inet6_dev *idev = in6_dev_get(dev);
916 if (unlikely(idev == NULL))
917 return NULL;
919 rt = ip6_dst_alloc();
920 if (unlikely(rt == NULL)) {
921 in6_dev_put(idev);
922 goto out;
925 dev_hold(dev);
926 if (neigh)
927 neigh_hold(neigh);
928 else
929 neigh = ndisc_get_neigh(dev, addr);
931 rt->rt6i_dev = dev;
932 rt->rt6i_idev = idev;
933 rt->rt6i_nexthop = neigh;
934 atomic_set(&rt->u.dst.__refcnt, 1);
935 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
936 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
937 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
938 rt->u.dst.output = output;
940 #if 0 /* there's no chance to use these for ndisc */
941 rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
942 ? DST_HOST
943 : 0;
944 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
945 rt->rt6i_dst.plen = 128;
946 #endif
948 spin_lock_bh(&ndisc_lock);
949 rt->u.dst.next = ndisc_dst_gc_list;
950 ndisc_dst_gc_list = &rt->u.dst;
951 spin_unlock_bh(&ndisc_lock);
953 fib6_force_start_gc();
955 out:
956 return &rt->u.dst;
959 int ndisc_dst_gc(int *more)
961 struct dst_entry *dst, *next, **pprev;
962 int freed;
964 next = NULL;
965 freed = 0;
967 spin_lock_bh(&ndisc_lock);
968 pprev = &ndisc_dst_gc_list;
970 while ((dst = *pprev) != NULL) {
971 if (!atomic_read(&dst->__refcnt)) {
972 *pprev = dst->next;
973 dst_free(dst);
974 freed++;
975 } else {
976 pprev = &dst->next;
977 (*more)++;
981 spin_unlock_bh(&ndisc_lock);
983 return freed;
986 static int ip6_dst_gc(struct dst_ops *ops)
988 static unsigned expire = 30*HZ;
989 static unsigned long last_gc;
990 unsigned long now = jiffies;
992 if (time_after(last_gc + init_net.ipv6.sysctl.ip6_rt_gc_min_interval, now) &&
993 atomic_read(&ip6_dst_ops.entries) <= init_net.ipv6.sysctl.ip6_rt_max_size)
994 goto out;
996 expire++;
997 fib6_run_gc(expire);
998 last_gc = now;
999 if (atomic_read(&ip6_dst_ops.entries) < ip6_dst_ops.gc_thresh)
1000 expire = init_net.ipv6.sysctl.ip6_rt_gc_timeout>>1;
1002 out:
1003 expire -= expire>>init_net.ipv6.sysctl.ip6_rt_gc_elasticity;
1004 return (atomic_read(&ip6_dst_ops.entries) > init_net.ipv6.sysctl.ip6_rt_max_size);
1007 /* Clean host part of a prefix. Not necessary in radix tree,
1008 but results in cleaner routing tables.
1010 Remove it only when all the things will work!
1013 static int ipv6_get_mtu(struct net_device *dev)
1015 int mtu = IPV6_MIN_MTU;
1016 struct inet6_dev *idev;
1018 idev = in6_dev_get(dev);
1019 if (idev) {
1020 mtu = idev->cnf.mtu6;
1021 in6_dev_put(idev);
1023 return mtu;
1026 int ipv6_get_hoplimit(struct net_device *dev)
1028 int hoplimit = ipv6_devconf.hop_limit;
1029 struct inet6_dev *idev;
1031 idev = in6_dev_get(dev);
1032 if (idev) {
1033 hoplimit = idev->cnf.hop_limit;
1034 in6_dev_put(idev);
1036 return hoplimit;
1043 int ip6_route_add(struct fib6_config *cfg)
1045 int err;
1046 struct rt6_info *rt = NULL;
1047 struct net_device *dev = NULL;
1048 struct inet6_dev *idev = NULL;
1049 struct fib6_table *table;
1050 int addr_type;
1052 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1053 return -EINVAL;
1054 #ifndef CONFIG_IPV6_SUBTREES
1055 if (cfg->fc_src_len)
1056 return -EINVAL;
1057 #endif
1058 if (cfg->fc_ifindex) {
1059 err = -ENODEV;
1060 dev = dev_get_by_index(&init_net, cfg->fc_ifindex);
1061 if (!dev)
1062 goto out;
1063 idev = in6_dev_get(dev);
1064 if (!idev)
1065 goto out;
1068 if (cfg->fc_metric == 0)
1069 cfg->fc_metric = IP6_RT_PRIO_USER;
1071 table = fib6_new_table(cfg->fc_table);
1072 if (table == NULL) {
1073 err = -ENOBUFS;
1074 goto out;
1077 rt = ip6_dst_alloc();
1079 if (rt == NULL) {
1080 err = -ENOMEM;
1081 goto out;
1084 rt->u.dst.obsolete = -1;
1085 rt->rt6i_expires = jiffies + clock_t_to_jiffies(cfg->fc_expires);
1087 if (cfg->fc_protocol == RTPROT_UNSPEC)
1088 cfg->fc_protocol = RTPROT_BOOT;
1089 rt->rt6i_protocol = cfg->fc_protocol;
1091 addr_type = ipv6_addr_type(&cfg->fc_dst);
1093 if (addr_type & IPV6_ADDR_MULTICAST)
1094 rt->u.dst.input = ip6_mc_input;
1095 else
1096 rt->u.dst.input = ip6_forward;
1098 rt->u.dst.output = ip6_output;
1100 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1101 rt->rt6i_dst.plen = cfg->fc_dst_len;
1102 if (rt->rt6i_dst.plen == 128)
1103 rt->u.dst.flags = DST_HOST;
1105 #ifdef CONFIG_IPV6_SUBTREES
1106 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1107 rt->rt6i_src.plen = cfg->fc_src_len;
1108 #endif
1110 rt->rt6i_metric = cfg->fc_metric;
1112 /* We cannot add true routes via loopback here,
1113 they would result in kernel looping; promote them to reject routes
1115 if ((cfg->fc_flags & RTF_REJECT) ||
1116 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
1117 /* hold loopback dev/idev if we haven't done so. */
1118 if (dev != init_net.loopback_dev) {
1119 if (dev) {
1120 dev_put(dev);
1121 in6_dev_put(idev);
1123 dev = init_net.loopback_dev;
1124 dev_hold(dev);
1125 idev = in6_dev_get(dev);
1126 if (!idev) {
1127 err = -ENODEV;
1128 goto out;
1131 rt->u.dst.output = ip6_pkt_discard_out;
1132 rt->u.dst.input = ip6_pkt_discard;
1133 rt->u.dst.error = -ENETUNREACH;
1134 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1135 goto install_route;
1138 if (cfg->fc_flags & RTF_GATEWAY) {
1139 struct in6_addr *gw_addr;
1140 int gwa_type;
1142 gw_addr = &cfg->fc_gateway;
1143 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1144 gwa_type = ipv6_addr_type(gw_addr);
1146 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1147 struct rt6_info *grt;
1149 /* IPv6 strictly inhibits using not link-local
1150 addresses as nexthop address.
1151 Otherwise, router will not able to send redirects.
1152 It is very good, but in some (rare!) circumstances
1153 (SIT, PtP, NBMA NOARP links) it is handy to allow
1154 some exceptions. --ANK
1156 err = -EINVAL;
1157 if (!(gwa_type&IPV6_ADDR_UNICAST))
1158 goto out;
1160 grt = rt6_lookup(gw_addr, NULL, cfg->fc_ifindex, 1);
1162 err = -EHOSTUNREACH;
1163 if (grt == NULL)
1164 goto out;
1165 if (dev) {
1166 if (dev != grt->rt6i_dev) {
1167 dst_release(&grt->u.dst);
1168 goto out;
1170 } else {
1171 dev = grt->rt6i_dev;
1172 idev = grt->rt6i_idev;
1173 dev_hold(dev);
1174 in6_dev_hold(grt->rt6i_idev);
1176 if (!(grt->rt6i_flags&RTF_GATEWAY))
1177 err = 0;
1178 dst_release(&grt->u.dst);
1180 if (err)
1181 goto out;
1183 err = -EINVAL;
1184 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1185 goto out;
1188 err = -ENODEV;
1189 if (dev == NULL)
1190 goto out;
1192 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1193 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1194 if (IS_ERR(rt->rt6i_nexthop)) {
1195 err = PTR_ERR(rt->rt6i_nexthop);
1196 rt->rt6i_nexthop = NULL;
1197 goto out;
1201 rt->rt6i_flags = cfg->fc_flags;
1203 install_route:
1204 if (cfg->fc_mx) {
1205 struct nlattr *nla;
1206 int remaining;
1208 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1209 int type = nla_type(nla);
1211 if (type) {
1212 if (type > RTAX_MAX) {
1213 err = -EINVAL;
1214 goto out;
1217 rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
1222 if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0)
1223 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1224 if (!rt->u.dst.metrics[RTAX_MTU-1])
1225 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
1226 if (!rt->u.dst.metrics[RTAX_ADVMSS-1])
1227 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1228 rt->u.dst.dev = dev;
1229 rt->rt6i_idev = idev;
1230 rt->rt6i_table = table;
1231 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1233 out:
1234 if (dev)
1235 dev_put(dev);
1236 if (idev)
1237 in6_dev_put(idev);
1238 if (rt)
1239 dst_free(&rt->u.dst);
1240 return err;
1243 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1245 int err;
1246 struct fib6_table *table;
1248 if (rt == &ip6_null_entry)
1249 return -ENOENT;
1251 table = rt->rt6i_table;
1252 write_lock_bh(&table->tb6_lock);
1254 err = fib6_del(rt, info);
1255 dst_release(&rt->u.dst);
1257 write_unlock_bh(&table->tb6_lock);
1259 return err;
1262 int ip6_del_rt(struct rt6_info *rt)
1264 struct nl_info info = {
1265 .nl_net = &init_net,
1267 return __ip6_del_rt(rt, &info);
1270 static int ip6_route_del(struct fib6_config *cfg)
1272 struct fib6_table *table;
1273 struct fib6_node *fn;
1274 struct rt6_info *rt;
1275 int err = -ESRCH;
1277 table = fib6_get_table(cfg->fc_table);
1278 if (table == NULL)
1279 return err;
1281 read_lock_bh(&table->tb6_lock);
1283 fn = fib6_locate(&table->tb6_root,
1284 &cfg->fc_dst, cfg->fc_dst_len,
1285 &cfg->fc_src, cfg->fc_src_len);
1287 if (fn) {
1288 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1289 if (cfg->fc_ifindex &&
1290 (rt->rt6i_dev == NULL ||
1291 rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1292 continue;
1293 if (cfg->fc_flags & RTF_GATEWAY &&
1294 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1295 continue;
1296 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1297 continue;
1298 dst_hold(&rt->u.dst);
1299 read_unlock_bh(&table->tb6_lock);
1301 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1304 read_unlock_bh(&table->tb6_lock);
1306 return err;
1310 * Handle redirects
1312 struct ip6rd_flowi {
1313 struct flowi fl;
1314 struct in6_addr gateway;
1317 static struct rt6_info *__ip6_route_redirect(struct fib6_table *table,
1318 struct flowi *fl,
1319 int flags)
1321 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
1322 struct rt6_info *rt;
1323 struct fib6_node *fn;
1326 * Get the "current" route for this destination and
1327 * check if the redirect has come from approriate router.
1329 * RFC 2461 specifies that redirects should only be
1330 * accepted if they come from the nexthop to the target.
1331 * Due to the way the routes are chosen, this notion
1332 * is a bit fuzzy and one might need to check all possible
1333 * routes.
1336 read_lock_bh(&table->tb6_lock);
1337 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1338 restart:
1339 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1341 * Current route is on-link; redirect is always invalid.
1343 * Seems, previous statement is not true. It could
1344 * be node, which looks for us as on-link (f.e. proxy ndisc)
1345 * But then router serving it might decide, that we should
1346 * know truth 8)8) --ANK (980726).
1348 if (rt6_check_expired(rt))
1349 continue;
1350 if (!(rt->rt6i_flags & RTF_GATEWAY))
1351 continue;
1352 if (fl->oif != rt->rt6i_dev->ifindex)
1353 continue;
1354 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1355 continue;
1356 break;
1359 if (!rt)
1360 rt = &ip6_null_entry;
1361 BACKTRACK(&fl->fl6_src);
1362 out:
1363 dst_hold(&rt->u.dst);
1365 read_unlock_bh(&table->tb6_lock);
1367 return rt;
1370 static struct rt6_info *ip6_route_redirect(struct in6_addr *dest,
1371 struct in6_addr *src,
1372 struct in6_addr *gateway,
1373 struct net_device *dev)
1375 int flags = RT6_LOOKUP_F_HAS_SADDR;
1376 struct ip6rd_flowi rdfl = {
1377 .fl = {
1378 .oif = dev->ifindex,
1379 .nl_u = {
1380 .ip6_u = {
1381 .daddr = *dest,
1382 .saddr = *src,
1386 .gateway = *gateway,
1389 if (rt6_need_strict(dest))
1390 flags |= RT6_LOOKUP_F_IFACE;
1392 return (struct rt6_info *)fib6_rule_lookup((struct flowi *)&rdfl, flags, __ip6_route_redirect);
1395 void rt6_redirect(struct in6_addr *dest, struct in6_addr *src,
1396 struct in6_addr *saddr,
1397 struct neighbour *neigh, u8 *lladdr, int on_link)
1399 struct rt6_info *rt, *nrt = NULL;
1400 struct netevent_redirect netevent;
1402 rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1404 if (rt == &ip6_null_entry) {
1405 if (net_ratelimit())
1406 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1407 "for redirect target\n");
1408 goto out;
1412 * We have finally decided to accept it.
1415 neigh_update(neigh, lladdr, NUD_STALE,
1416 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1417 NEIGH_UPDATE_F_OVERRIDE|
1418 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1419 NEIGH_UPDATE_F_ISROUTER))
1423 * Redirect received -> path was valid.
1424 * Look, redirects are sent only in response to data packets,
1425 * so that this nexthop apparently is reachable. --ANK
1427 dst_confirm(&rt->u.dst);
1429 /* Duplicate redirect: silently ignore. */
1430 if (neigh == rt->u.dst.neighbour)
1431 goto out;
1433 nrt = ip6_rt_copy(rt);
1434 if (nrt == NULL)
1435 goto out;
1437 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1438 if (on_link)
1439 nrt->rt6i_flags &= ~RTF_GATEWAY;
1441 ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1442 nrt->rt6i_dst.plen = 128;
1443 nrt->u.dst.flags |= DST_HOST;
1445 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1446 nrt->rt6i_nexthop = neigh_clone(neigh);
1447 /* Reset pmtu, it may be better */
1448 nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
1449 nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&nrt->u.dst));
1451 if (ip6_ins_rt(nrt))
1452 goto out;
1454 netevent.old = &rt->u.dst;
1455 netevent.new = &nrt->u.dst;
1456 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1458 if (rt->rt6i_flags&RTF_CACHE) {
1459 ip6_del_rt(rt);
1460 return;
1463 out:
1464 dst_release(&rt->u.dst);
1465 return;
1469 * Handle ICMP "packet too big" messages
1470 * i.e. Path MTU discovery
1473 void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
1474 struct net_device *dev, u32 pmtu)
1476 struct rt6_info *rt, *nrt;
1477 int allfrag = 0;
1479 rt = rt6_lookup(daddr, saddr, dev->ifindex, 0);
1480 if (rt == NULL)
1481 return;
1483 if (pmtu >= dst_mtu(&rt->u.dst))
1484 goto out;
1486 if (pmtu < IPV6_MIN_MTU) {
1488 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1489 * MTU (1280) and a fragment header should always be included
1490 * after a node receiving Too Big message reporting PMTU is
1491 * less than the IPv6 Minimum Link MTU.
1493 pmtu = IPV6_MIN_MTU;
1494 allfrag = 1;
1497 /* New mtu received -> path was valid.
1498 They are sent only in response to data packets,
1499 so that this nexthop apparently is reachable. --ANK
1501 dst_confirm(&rt->u.dst);
1503 /* Host route. If it is static, it would be better
1504 not to override it, but add new one, so that
1505 when cache entry will expire old pmtu
1506 would return automatically.
1508 if (rt->rt6i_flags & RTF_CACHE) {
1509 rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1510 if (allfrag)
1511 rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1512 dst_set_expires(&rt->u.dst, init_net.ipv6.sysctl.ip6_rt_mtu_expires);
1513 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1514 goto out;
1517 /* Network route.
1518 Two cases are possible:
1519 1. It is connected route. Action: COW
1520 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1522 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1523 nrt = rt6_alloc_cow(rt, daddr, saddr);
1524 else
1525 nrt = rt6_alloc_clone(rt, daddr);
1527 if (nrt) {
1528 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1529 if (allfrag)
1530 nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1532 /* According to RFC 1981, detecting PMTU increase shouldn't be
1533 * happened within 5 mins, the recommended timer is 10 mins.
1534 * Here this route expiration time is set to ip6_rt_mtu_expires
1535 * which is 10 mins. After 10 mins the decreased pmtu is expired
1536 * and detecting PMTU increase will be automatically happened.
1538 dst_set_expires(&nrt->u.dst, init_net.ipv6.sysctl.ip6_rt_mtu_expires);
1539 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1541 ip6_ins_rt(nrt);
1543 out:
1544 dst_release(&rt->u.dst);
1548 * Misc support functions
1551 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1553 struct rt6_info *rt = ip6_dst_alloc();
1555 if (rt) {
1556 rt->u.dst.input = ort->u.dst.input;
1557 rt->u.dst.output = ort->u.dst.output;
1559 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1560 rt->u.dst.error = ort->u.dst.error;
1561 rt->u.dst.dev = ort->u.dst.dev;
1562 if (rt->u.dst.dev)
1563 dev_hold(rt->u.dst.dev);
1564 rt->rt6i_idev = ort->rt6i_idev;
1565 if (rt->rt6i_idev)
1566 in6_dev_hold(rt->rt6i_idev);
1567 rt->u.dst.lastuse = jiffies;
1568 rt->rt6i_expires = 0;
1570 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1571 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1572 rt->rt6i_metric = 0;
1574 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1575 #ifdef CONFIG_IPV6_SUBTREES
1576 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1577 #endif
1578 rt->rt6i_table = ort->rt6i_table;
1580 return rt;
1583 #ifdef CONFIG_IPV6_ROUTE_INFO
1584 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
1585 struct in6_addr *gwaddr, int ifindex)
1587 struct fib6_node *fn;
1588 struct rt6_info *rt = NULL;
1589 struct fib6_table *table;
1591 table = fib6_get_table(RT6_TABLE_INFO);
1592 if (table == NULL)
1593 return NULL;
1595 write_lock_bh(&table->tb6_lock);
1596 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1597 if (!fn)
1598 goto out;
1600 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1601 if (rt->rt6i_dev->ifindex != ifindex)
1602 continue;
1603 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1604 continue;
1605 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1606 continue;
1607 dst_hold(&rt->u.dst);
1608 break;
1610 out:
1611 write_unlock_bh(&table->tb6_lock);
1612 return rt;
1615 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
1616 struct in6_addr *gwaddr, int ifindex,
1617 unsigned pref)
1619 struct fib6_config cfg = {
1620 .fc_table = RT6_TABLE_INFO,
1621 .fc_metric = 1024,
1622 .fc_ifindex = ifindex,
1623 .fc_dst_len = prefixlen,
1624 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1625 RTF_UP | RTF_PREF(pref),
1628 ipv6_addr_copy(&cfg.fc_dst, prefix);
1629 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1631 /* We should treat it as a default route if prefix length is 0. */
1632 if (!prefixlen)
1633 cfg.fc_flags |= RTF_DEFAULT;
1635 ip6_route_add(&cfg);
1637 return rt6_get_route_info(prefix, prefixlen, gwaddr, ifindex);
1639 #endif
1641 struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1643 struct rt6_info *rt;
1644 struct fib6_table *table;
1646 table = fib6_get_table(RT6_TABLE_DFLT);
1647 if (table == NULL)
1648 return NULL;
1650 write_lock_bh(&table->tb6_lock);
1651 for (rt = table->tb6_root.leaf; rt; rt=rt->u.dst.rt6_next) {
1652 if (dev == rt->rt6i_dev &&
1653 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1654 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1655 break;
1657 if (rt)
1658 dst_hold(&rt->u.dst);
1659 write_unlock_bh(&table->tb6_lock);
1660 return rt;
1663 EXPORT_SYMBOL(rt6_get_dflt_router);
1665 struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1666 struct net_device *dev,
1667 unsigned int pref)
1669 struct fib6_config cfg = {
1670 .fc_table = RT6_TABLE_DFLT,
1671 .fc_metric = 1024,
1672 .fc_ifindex = dev->ifindex,
1673 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1674 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1677 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1679 ip6_route_add(&cfg);
1681 return rt6_get_dflt_router(gwaddr, dev);
1684 void rt6_purge_dflt_routers(void)
1686 struct rt6_info *rt;
1687 struct fib6_table *table;
1689 /* NOTE: Keep consistent with rt6_get_dflt_router */
1690 table = fib6_get_table(RT6_TABLE_DFLT);
1691 if (table == NULL)
1692 return;
1694 restart:
1695 read_lock_bh(&table->tb6_lock);
1696 for (rt = table->tb6_root.leaf; rt; rt = rt->u.dst.rt6_next) {
1697 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1698 dst_hold(&rt->u.dst);
1699 read_unlock_bh(&table->tb6_lock);
1700 ip6_del_rt(rt);
1701 goto restart;
1704 read_unlock_bh(&table->tb6_lock);
1707 static void rtmsg_to_fib6_config(struct in6_rtmsg *rtmsg,
1708 struct fib6_config *cfg)
1710 memset(cfg, 0, sizeof(*cfg));
1712 cfg->fc_table = RT6_TABLE_MAIN;
1713 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1714 cfg->fc_metric = rtmsg->rtmsg_metric;
1715 cfg->fc_expires = rtmsg->rtmsg_info;
1716 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1717 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1718 cfg->fc_flags = rtmsg->rtmsg_flags;
1720 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1721 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1722 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1725 int ipv6_route_ioctl(unsigned int cmd, void __user *arg)
1727 struct fib6_config cfg;
1728 struct in6_rtmsg rtmsg;
1729 int err;
1731 switch(cmd) {
1732 case SIOCADDRT: /* Add a route */
1733 case SIOCDELRT: /* Delete a route */
1734 if (!capable(CAP_NET_ADMIN))
1735 return -EPERM;
1736 err = copy_from_user(&rtmsg, arg,
1737 sizeof(struct in6_rtmsg));
1738 if (err)
1739 return -EFAULT;
1741 rtmsg_to_fib6_config(&rtmsg, &cfg);
1743 rtnl_lock();
1744 switch (cmd) {
1745 case SIOCADDRT:
1746 err = ip6_route_add(&cfg);
1747 break;
1748 case SIOCDELRT:
1749 err = ip6_route_del(&cfg);
1750 break;
1751 default:
1752 err = -EINVAL;
1754 rtnl_unlock();
1756 return err;
1759 return -EINVAL;
1763 * Drop the packet on the floor
1766 static int ip6_pkt_drop(struct sk_buff *skb, int code, int ipstats_mib_noroutes)
1768 int type;
1769 switch (ipstats_mib_noroutes) {
1770 case IPSTATS_MIB_INNOROUTES:
1771 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
1772 if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED) {
1773 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INADDRERRORS);
1774 break;
1776 /* FALLTHROUGH */
1777 case IPSTATS_MIB_OUTNOROUTES:
1778 IP6_INC_STATS(ip6_dst_idev(skb->dst), ipstats_mib_noroutes);
1779 break;
1781 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev);
1782 kfree_skb(skb);
1783 return 0;
1786 static int ip6_pkt_discard(struct sk_buff *skb)
1788 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
1791 static int ip6_pkt_discard_out(struct sk_buff *skb)
1793 skb->dev = skb->dst->dev;
1794 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
1797 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1799 static int ip6_pkt_prohibit(struct sk_buff *skb)
1801 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
1804 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
1806 skb->dev = skb->dst->dev;
1807 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
1810 #endif
1813 * Allocate a dst for local (unicast / anycast) address.
1816 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
1817 const struct in6_addr *addr,
1818 int anycast)
1820 struct rt6_info *rt = ip6_dst_alloc();
1822 if (rt == NULL)
1823 return ERR_PTR(-ENOMEM);
1825 dev_hold(init_net.loopback_dev);
1826 in6_dev_hold(idev);
1828 rt->u.dst.flags = DST_HOST;
1829 rt->u.dst.input = ip6_input;
1830 rt->u.dst.output = ip6_output;
1831 rt->rt6i_dev = init_net.loopback_dev;
1832 rt->rt6i_idev = idev;
1833 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1834 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1835 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1836 rt->u.dst.obsolete = -1;
1838 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1839 if (anycast)
1840 rt->rt6i_flags |= RTF_ANYCAST;
1841 else
1842 rt->rt6i_flags |= RTF_LOCAL;
1843 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
1844 if (rt->rt6i_nexthop == NULL) {
1845 dst_free(&rt->u.dst);
1846 return ERR_PTR(-ENOMEM);
1849 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1850 rt->rt6i_dst.plen = 128;
1851 rt->rt6i_table = fib6_get_table(RT6_TABLE_LOCAL);
1853 atomic_set(&rt->u.dst.__refcnt, 1);
1855 return rt;
1858 static int fib6_ifdown(struct rt6_info *rt, void *arg)
1860 if (((void*)rt->rt6i_dev == arg || arg == NULL) &&
1861 rt != &ip6_null_entry) {
1862 RT6_TRACE("deleted by ifdown %p\n", rt);
1863 return -1;
1865 return 0;
1868 void rt6_ifdown(struct net_device *dev)
1870 fib6_clean_all(fib6_ifdown, 0, dev);
1873 struct rt6_mtu_change_arg
1875 struct net_device *dev;
1876 unsigned mtu;
1879 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
1881 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
1882 struct inet6_dev *idev;
1884 /* In IPv6 pmtu discovery is not optional,
1885 so that RTAX_MTU lock cannot disable it.
1886 We still use this lock to block changes
1887 caused by addrconf/ndisc.
1890 idev = __in6_dev_get(arg->dev);
1891 if (idev == NULL)
1892 return 0;
1894 /* For administrative MTU increase, there is no way to discover
1895 IPv6 PMTU increase, so PMTU increase should be updated here.
1896 Since RFC 1981 doesn't include administrative MTU increase
1897 update PMTU increase is a MUST. (i.e. jumbo frame)
1900 If new MTU is less than route PMTU, this new MTU will be the
1901 lowest MTU in the path, update the route PMTU to reflect PMTU
1902 decreases; if new MTU is greater than route PMTU, and the
1903 old MTU is the lowest MTU in the path, update the route PMTU
1904 to reflect the increase. In this case if the other nodes' MTU
1905 also have the lowest MTU, TOO BIG MESSAGE will be lead to
1906 PMTU discouvery.
1908 if (rt->rt6i_dev == arg->dev &&
1909 !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1910 (dst_mtu(&rt->u.dst) > arg->mtu ||
1911 (dst_mtu(&rt->u.dst) < arg->mtu &&
1912 dst_mtu(&rt->u.dst) == idev->cnf.mtu6))) {
1913 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
1914 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(arg->mtu);
1916 return 0;
1919 void rt6_mtu_change(struct net_device *dev, unsigned mtu)
1921 struct rt6_mtu_change_arg arg = {
1922 .dev = dev,
1923 .mtu = mtu,
1926 fib6_clean_all(rt6_mtu_change_route, 0, &arg);
1929 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
1930 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
1931 [RTA_OIF] = { .type = NLA_U32 },
1932 [RTA_IIF] = { .type = NLA_U32 },
1933 [RTA_PRIORITY] = { .type = NLA_U32 },
1934 [RTA_METRICS] = { .type = NLA_NESTED },
1937 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
1938 struct fib6_config *cfg)
1940 struct rtmsg *rtm;
1941 struct nlattr *tb[RTA_MAX+1];
1942 int err;
1944 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
1945 if (err < 0)
1946 goto errout;
1948 err = -EINVAL;
1949 rtm = nlmsg_data(nlh);
1950 memset(cfg, 0, sizeof(*cfg));
1952 cfg->fc_table = rtm->rtm_table;
1953 cfg->fc_dst_len = rtm->rtm_dst_len;
1954 cfg->fc_src_len = rtm->rtm_src_len;
1955 cfg->fc_flags = RTF_UP;
1956 cfg->fc_protocol = rtm->rtm_protocol;
1958 if (rtm->rtm_type == RTN_UNREACHABLE)
1959 cfg->fc_flags |= RTF_REJECT;
1961 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
1962 cfg->fc_nlinfo.nlh = nlh;
1964 if (tb[RTA_GATEWAY]) {
1965 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
1966 cfg->fc_flags |= RTF_GATEWAY;
1969 if (tb[RTA_DST]) {
1970 int plen = (rtm->rtm_dst_len + 7) >> 3;
1972 if (nla_len(tb[RTA_DST]) < plen)
1973 goto errout;
1975 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
1978 if (tb[RTA_SRC]) {
1979 int plen = (rtm->rtm_src_len + 7) >> 3;
1981 if (nla_len(tb[RTA_SRC]) < plen)
1982 goto errout;
1984 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
1987 if (tb[RTA_OIF])
1988 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
1990 if (tb[RTA_PRIORITY])
1991 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
1993 if (tb[RTA_METRICS]) {
1994 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
1995 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
1998 if (tb[RTA_TABLE])
1999 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2001 err = 0;
2002 errout:
2003 return err;
2006 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2008 struct net *net = skb->sk->sk_net;
2009 struct fib6_config cfg;
2010 int err;
2012 if (net != &init_net)
2013 return -EINVAL;
2015 err = rtm_to_fib6_config(skb, nlh, &cfg);
2016 if (err < 0)
2017 return err;
2019 return ip6_route_del(&cfg);
2022 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2024 struct net *net = skb->sk->sk_net;
2025 struct fib6_config cfg;
2026 int err;
2028 if (net != &init_net)
2029 return -EINVAL;
2031 err = rtm_to_fib6_config(skb, nlh, &cfg);
2032 if (err < 0)
2033 return err;
2035 return ip6_route_add(&cfg);
2038 static inline size_t rt6_nlmsg_size(void)
2040 return NLMSG_ALIGN(sizeof(struct rtmsg))
2041 + nla_total_size(16) /* RTA_SRC */
2042 + nla_total_size(16) /* RTA_DST */
2043 + nla_total_size(16) /* RTA_GATEWAY */
2044 + nla_total_size(16) /* RTA_PREFSRC */
2045 + nla_total_size(4) /* RTA_TABLE */
2046 + nla_total_size(4) /* RTA_IIF */
2047 + nla_total_size(4) /* RTA_OIF */
2048 + nla_total_size(4) /* RTA_PRIORITY */
2049 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2050 + nla_total_size(sizeof(struct rta_cacheinfo));
2053 static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
2054 struct in6_addr *dst, struct in6_addr *src,
2055 int iif, int type, u32 pid, u32 seq,
2056 int prefix, unsigned int flags)
2058 struct rtmsg *rtm;
2059 struct nlmsghdr *nlh;
2060 long expires;
2061 u32 table;
2063 if (prefix) { /* user wants prefix routes only */
2064 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2065 /* success since this is not a prefix route */
2066 return 1;
2070 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2071 if (nlh == NULL)
2072 return -EMSGSIZE;
2074 rtm = nlmsg_data(nlh);
2075 rtm->rtm_family = AF_INET6;
2076 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2077 rtm->rtm_src_len = rt->rt6i_src.plen;
2078 rtm->rtm_tos = 0;
2079 if (rt->rt6i_table)
2080 table = rt->rt6i_table->tb6_id;
2081 else
2082 table = RT6_TABLE_UNSPEC;
2083 rtm->rtm_table = table;
2084 NLA_PUT_U32(skb, RTA_TABLE, table);
2085 if (rt->rt6i_flags&RTF_REJECT)
2086 rtm->rtm_type = RTN_UNREACHABLE;
2087 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2088 rtm->rtm_type = RTN_LOCAL;
2089 else
2090 rtm->rtm_type = RTN_UNICAST;
2091 rtm->rtm_flags = 0;
2092 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2093 rtm->rtm_protocol = rt->rt6i_protocol;
2094 if (rt->rt6i_flags&RTF_DYNAMIC)
2095 rtm->rtm_protocol = RTPROT_REDIRECT;
2096 else if (rt->rt6i_flags & RTF_ADDRCONF)
2097 rtm->rtm_protocol = RTPROT_KERNEL;
2098 else if (rt->rt6i_flags&RTF_DEFAULT)
2099 rtm->rtm_protocol = RTPROT_RA;
2101 if (rt->rt6i_flags&RTF_CACHE)
2102 rtm->rtm_flags |= RTM_F_CLONED;
2104 if (dst) {
2105 NLA_PUT(skb, RTA_DST, 16, dst);
2106 rtm->rtm_dst_len = 128;
2107 } else if (rtm->rtm_dst_len)
2108 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2109 #ifdef CONFIG_IPV6_SUBTREES
2110 if (src) {
2111 NLA_PUT(skb, RTA_SRC, 16, src);
2112 rtm->rtm_src_len = 128;
2113 } else if (rtm->rtm_src_len)
2114 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2115 #endif
2116 if (iif)
2117 NLA_PUT_U32(skb, RTA_IIF, iif);
2118 else if (dst) {
2119 struct in6_addr saddr_buf;
2120 if (ipv6_get_saddr(&rt->u.dst, dst, &saddr_buf) == 0)
2121 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2124 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2125 goto nla_put_failure;
2127 if (rt->u.dst.neighbour)
2128 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);
2130 if (rt->u.dst.dev)
2131 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2133 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2135 expires = rt->rt6i_expires ? rt->rt6i_expires - jiffies : 0;
2136 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0,
2137 expires, rt->u.dst.error) < 0)
2138 goto nla_put_failure;
2140 return nlmsg_end(skb, nlh);
2142 nla_put_failure:
2143 nlmsg_cancel(skb, nlh);
2144 return -EMSGSIZE;
2147 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2149 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2150 int prefix;
2152 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2153 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2154 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2155 } else
2156 prefix = 0;
2158 return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2159 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2160 prefix, NLM_F_MULTI);
2163 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2165 struct net *net = in_skb->sk->sk_net;
2166 struct nlattr *tb[RTA_MAX+1];
2167 struct rt6_info *rt;
2168 struct sk_buff *skb;
2169 struct rtmsg *rtm;
2170 struct flowi fl;
2171 int err, iif = 0;
2173 if (net != &init_net)
2174 return -EINVAL;
2176 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2177 if (err < 0)
2178 goto errout;
2180 err = -EINVAL;
2181 memset(&fl, 0, sizeof(fl));
2183 if (tb[RTA_SRC]) {
2184 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2185 goto errout;
2187 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
2190 if (tb[RTA_DST]) {
2191 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2192 goto errout;
2194 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
2197 if (tb[RTA_IIF])
2198 iif = nla_get_u32(tb[RTA_IIF]);
2200 if (tb[RTA_OIF])
2201 fl.oif = nla_get_u32(tb[RTA_OIF]);
2203 if (iif) {
2204 struct net_device *dev;
2205 dev = __dev_get_by_index(&init_net, iif);
2206 if (!dev) {
2207 err = -ENODEV;
2208 goto errout;
2212 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2213 if (skb == NULL) {
2214 err = -ENOBUFS;
2215 goto errout;
2218 /* Reserve room for dummy headers, this skb can pass
2219 through good chunk of routing engine.
2221 skb_reset_mac_header(skb);
2222 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2224 rt = (struct rt6_info*) ip6_route_output(NULL, &fl);
2225 skb->dst = &rt->u.dst;
2227 err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
2228 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2229 nlh->nlmsg_seq, 0, 0);
2230 if (err < 0) {
2231 kfree_skb(skb);
2232 goto errout;
2235 err = rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).pid);
2236 errout:
2237 return err;
2240 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2242 struct sk_buff *skb;
2243 u32 seq;
2244 int err;
2246 err = -ENOBUFS;
2247 seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0;
2249 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2250 if (skb == NULL)
2251 goto errout;
2253 err = rt6_fill_node(skb, rt, NULL, NULL, 0,
2254 event, info->pid, seq, 0, 0);
2255 if (err < 0) {
2256 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2257 WARN_ON(err == -EMSGSIZE);
2258 kfree_skb(skb);
2259 goto errout;
2261 err = rtnl_notify(skb, &init_net, info->pid,
2262 RTNLGRP_IPV6_ROUTE, info->nlh, gfp_any());
2263 errout:
2264 if (err < 0)
2265 rtnl_set_sk_err(&init_net, RTNLGRP_IPV6_ROUTE, err);
2269 * /proc
2272 #ifdef CONFIG_PROC_FS
2274 #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)
2276 struct rt6_proc_arg
2278 char *buffer;
2279 int offset;
2280 int length;
2281 int skip;
2282 int len;
2285 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2287 struct seq_file *m = p_arg;
2289 seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_dst.addr),
2290 rt->rt6i_dst.plen);
2292 #ifdef CONFIG_IPV6_SUBTREES
2293 seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_src.addr),
2294 rt->rt6i_src.plen);
2295 #else
2296 seq_puts(m, "00000000000000000000000000000000 00 ");
2297 #endif
2299 if (rt->rt6i_nexthop) {
2300 seq_printf(m, NIP6_SEQFMT,
2301 NIP6(*((struct in6_addr *)rt->rt6i_nexthop->primary_key)));
2302 } else {
2303 seq_puts(m, "00000000000000000000000000000000");
2305 seq_printf(m, " %08x %08x %08x %08x %8s\n",
2306 rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2307 rt->u.dst.__use, rt->rt6i_flags,
2308 rt->rt6i_dev ? rt->rt6i_dev->name : "");
2309 return 0;
2312 static int ipv6_route_show(struct seq_file *m, void *v)
2314 fib6_clean_all(rt6_info_route, 0, m);
2315 return 0;
2318 static int ipv6_route_open(struct inode *inode, struct file *file)
2320 return single_open(file, ipv6_route_show, NULL);
2323 static const struct file_operations ipv6_route_proc_fops = {
2324 .owner = THIS_MODULE,
2325 .open = ipv6_route_open,
2326 .read = seq_read,
2327 .llseek = seq_lseek,
2328 .release = single_release,
2331 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2333 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2334 rt6_stats.fib_nodes, rt6_stats.fib_route_nodes,
2335 rt6_stats.fib_rt_alloc, rt6_stats.fib_rt_entries,
2336 rt6_stats.fib_rt_cache,
2337 atomic_read(&ip6_dst_ops.entries),
2338 rt6_stats.fib_discarded_routes);
2340 return 0;
2343 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2345 return single_open(file, rt6_stats_seq_show, NULL);
2348 static const struct file_operations rt6_stats_seq_fops = {
2349 .owner = THIS_MODULE,
2350 .open = rt6_stats_seq_open,
2351 .read = seq_read,
2352 .llseek = seq_lseek,
2353 .release = single_release,
2356 static int ipv6_route_proc_init(struct net *net)
2358 int ret = -ENOMEM;
2359 if (!proc_net_fops_create(net, "ipv6_route",
2360 0, &ipv6_route_proc_fops))
2361 goto out;
2363 if (!proc_net_fops_create(net, "rt6_stats",
2364 S_IRUGO, &rt6_stats_seq_fops))
2365 goto out_ipv6_route;
2367 ret = 0;
2368 out:
2369 return ret;
2370 out_ipv6_route:
2371 proc_net_remove(net, "ipv6_route");
2372 goto out;
2375 static void ipv6_route_proc_fini(struct net *net)
2377 proc_net_remove(net, "ipv6_route");
2378 proc_net_remove(net, "rt6_stats");
2380 #else
2381 static inline int ipv6_route_proc_init(struct net *net)
2383 return 0;
2385 static inline void ipv6_route_proc_fini(struct net *net)
2387 return ;
2389 #endif /* CONFIG_PROC_FS */
2391 #ifdef CONFIG_SYSCTL
2393 static
2394 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp,
2395 void __user *buffer, size_t *lenp, loff_t *ppos)
2397 int delay = init_net.ipv6.sysctl.flush_delay;
2398 if (write) {
2399 proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
2400 fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay);
2401 return 0;
2402 } else
2403 return -EINVAL;
2406 ctl_table ipv6_route_table_template[] = {
2408 .procname = "flush",
2409 .data = &init_net.ipv6.sysctl.flush_delay,
2410 .maxlen = sizeof(int),
2411 .mode = 0200,
2412 .proc_handler = &ipv6_sysctl_rtcache_flush
2415 .ctl_name = NET_IPV6_ROUTE_GC_THRESH,
2416 .procname = "gc_thresh",
2417 .data = &ip6_dst_ops.gc_thresh,
2418 .maxlen = sizeof(int),
2419 .mode = 0644,
2420 .proc_handler = &proc_dointvec,
2423 .ctl_name = NET_IPV6_ROUTE_MAX_SIZE,
2424 .procname = "max_size",
2425 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
2426 .maxlen = sizeof(int),
2427 .mode = 0644,
2428 .proc_handler = &proc_dointvec,
2431 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL,
2432 .procname = "gc_min_interval",
2433 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2434 .maxlen = sizeof(int),
2435 .mode = 0644,
2436 .proc_handler = &proc_dointvec_jiffies,
2437 .strategy = &sysctl_jiffies,
2440 .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT,
2441 .procname = "gc_timeout",
2442 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
2443 .maxlen = sizeof(int),
2444 .mode = 0644,
2445 .proc_handler = &proc_dointvec_jiffies,
2446 .strategy = &sysctl_jiffies,
2449 .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL,
2450 .procname = "gc_interval",
2451 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
2452 .maxlen = sizeof(int),
2453 .mode = 0644,
2454 .proc_handler = &proc_dointvec_jiffies,
2455 .strategy = &sysctl_jiffies,
2458 .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY,
2459 .procname = "gc_elasticity",
2460 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
2461 .maxlen = sizeof(int),
2462 .mode = 0644,
2463 .proc_handler = &proc_dointvec_jiffies,
2464 .strategy = &sysctl_jiffies,
2467 .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES,
2468 .procname = "mtu_expires",
2469 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
2470 .maxlen = sizeof(int),
2471 .mode = 0644,
2472 .proc_handler = &proc_dointvec_jiffies,
2473 .strategy = &sysctl_jiffies,
2476 .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS,
2477 .procname = "min_adv_mss",
2478 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
2479 .maxlen = sizeof(int),
2480 .mode = 0644,
2481 .proc_handler = &proc_dointvec_jiffies,
2482 .strategy = &sysctl_jiffies,
2485 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS,
2486 .procname = "gc_min_interval_ms",
2487 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2488 .maxlen = sizeof(int),
2489 .mode = 0644,
2490 .proc_handler = &proc_dointvec_ms_jiffies,
2491 .strategy = &sysctl_ms_jiffies,
2493 { .ctl_name = 0 }
2496 struct ctl_table *ipv6_route_sysctl_init(struct net *net)
2498 struct ctl_table *table;
2500 table = kmemdup(ipv6_route_table_template,
2501 sizeof(ipv6_route_table_template),
2502 GFP_KERNEL);
2503 return table;
2505 #endif
2507 int __init ip6_route_init(void)
2509 int ret;
2511 ip6_dst_ops.kmem_cachep =
2512 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2513 SLAB_HWCACHE_ALIGN, NULL);
2514 if (!ip6_dst_ops.kmem_cachep)
2515 return -ENOMEM;
2517 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops.kmem_cachep;
2519 ret = fib6_init();
2520 if (ret)
2521 goto out_kmem_cache;
2523 ret = ipv6_route_proc_init(&init_net);
2524 if (ret)
2525 goto out_fib6_init;
2527 ret = xfrm6_init();
2528 if (ret)
2529 goto out_proc_init;
2531 ret = fib6_rules_init();
2532 if (ret)
2533 goto xfrm6_init;
2535 ret = -ENOBUFS;
2536 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) ||
2537 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) ||
2538 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL))
2539 goto fib6_rules_init;
2541 ret = 0;
2542 out:
2543 return ret;
2545 fib6_rules_init:
2546 fib6_rules_cleanup();
2547 xfrm6_init:
2548 xfrm6_fini();
2549 out_proc_init:
2550 ipv6_route_proc_fini(&init_net);
2551 out_fib6_init:
2552 rt6_ifdown(NULL);
2553 fib6_gc_cleanup();
2554 out_kmem_cache:
2555 kmem_cache_destroy(ip6_dst_ops.kmem_cachep);
2556 goto out;
2559 void ip6_route_cleanup(void)
2561 fib6_rules_cleanup();
2562 ipv6_route_proc_fini(&init_net);
2563 xfrm6_fini();
2564 rt6_ifdown(NULL);
2565 fib6_gc_cleanup();
2566 kmem_cache_destroy(ip6_dst_ops.kmem_cachep);