2 * Linux INET6 implementation
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.
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.
27 #include <linux/capability.h>
28 #include <linux/errno.h>
29 #include <linux/types.h>
30 #include <linux/times.h>
31 #include <linux/socket.h>
32 #include <linux/sockios.h>
33 #include <linux/net.h>
34 #include <linux/route.h>
35 #include <linux/netdevice.h>
36 #include <linux/in6.h>
37 #include <linux/init.h>
38 #include <linux/if_arp.h>
41 #include <linux/proc_fs.h>
42 #include <linux/seq_file.h>
47 #include <net/ip6_fib.h>
48 #include <net/ip6_route.h>
49 #include <net/ndisc.h>
50 #include <net/addrconf.h>
52 #include <linux/rtnetlink.h>
55 #include <net/netevent.h>
56 #include <net/netlink.h>
58 #include <asm/uaccess.h>
61 #include <linux/sysctl.h>
64 /* Set to 3 to get tracing. */
68 #define RDBG(x) printk x
69 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
72 #define RT6_TRACE(x...) do { ; } while (0)
75 #define CLONE_OFFLINK_ROUTE 0
77 #define RT6_SELECT_F_IFACE 0x1
78 #define RT6_SELECT_F_REACHABLE 0x2
80 static int ip6_rt_max_size = 4096;
81 static int ip6_rt_gc_min_interval = HZ / 2;
82 static int ip6_rt_gc_timeout = 60*HZ;
83 int ip6_rt_gc_interval = 30*HZ;
84 static int ip6_rt_gc_elasticity = 9;
85 static int ip6_rt_mtu_expires = 10*60*HZ;
86 static int ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
88 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
89 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
90 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
91 static void ip6_dst_destroy(struct dst_entry *);
92 static void ip6_dst_ifdown(struct dst_entry *,
93 struct net_device *dev, int how);
94 static int ip6_dst_gc(void);
96 static int ip6_pkt_discard(struct sk_buff *skb);
97 static int ip6_pkt_discard_out(struct sk_buff *skb);
98 static void ip6_link_failure(struct sk_buff *skb);
99 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
101 #ifdef CONFIG_IPV6_ROUTE_INFO
102 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
103 struct in6_addr *gwaddr, int ifindex,
105 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
106 struct in6_addr *gwaddr, int ifindex);
109 static struct dst_ops ip6_dst_ops = {
111 .protocol = __constant_htons(ETH_P_IPV6),
114 .check = ip6_dst_check,
115 .destroy = ip6_dst_destroy,
116 .ifdown = ip6_dst_ifdown,
117 .negative_advice = ip6_negative_advice,
118 .link_failure = ip6_link_failure,
119 .update_pmtu = ip6_rt_update_pmtu,
120 .entry_size = sizeof(struct rt6_info),
123 struct rt6_info ip6_null_entry = {
126 .__refcnt = ATOMIC_INIT(1),
128 .dev = &loopback_dev,
130 .error = -ENETUNREACH,
131 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
132 .input = ip6_pkt_discard,
133 .output = ip6_pkt_discard_out,
135 .path = (struct dst_entry*)&ip6_null_entry,
138 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
139 .rt6i_metric = ~(u32) 0,
140 .rt6i_ref = ATOMIC_INIT(1),
143 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
145 struct rt6_info ip6_prohibit_entry = {
148 .__refcnt = ATOMIC_INIT(1),
150 .dev = &loopback_dev,
153 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
154 .input = ip6_pkt_discard,
155 .output = ip6_pkt_discard_out,
157 .path = (struct dst_entry*)&ip6_prohibit_entry,
160 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
161 .rt6i_metric = ~(u32) 0,
162 .rt6i_ref = ATOMIC_INIT(1),
165 struct rt6_info ip6_blk_hole_entry = {
168 .__refcnt = ATOMIC_INIT(1),
170 .dev = &loopback_dev,
173 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
174 .input = ip6_pkt_discard,
175 .output = ip6_pkt_discard_out,
177 .path = (struct dst_entry*)&ip6_blk_hole_entry,
180 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
181 .rt6i_metric = ~(u32) 0,
182 .rt6i_ref = ATOMIC_INIT(1),
187 /* allocate dst with ip6_dst_ops */
188 static __inline__ struct rt6_info *ip6_dst_alloc(void)
190 return (struct rt6_info *)dst_alloc(&ip6_dst_ops);
193 static void ip6_dst_destroy(struct dst_entry *dst)
195 struct rt6_info *rt = (struct rt6_info *)dst;
196 struct inet6_dev *idev = rt->rt6i_idev;
199 rt->rt6i_idev = NULL;
204 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
207 struct rt6_info *rt = (struct rt6_info *)dst;
208 struct inet6_dev *idev = rt->rt6i_idev;
210 if (dev != &loopback_dev && idev != NULL && idev->dev == dev) {
211 struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev);
212 if (loopback_idev != NULL) {
213 rt->rt6i_idev = loopback_idev;
219 static __inline__ int rt6_check_expired(const struct rt6_info *rt)
221 return (rt->rt6i_flags & RTF_EXPIRES &&
222 time_after(jiffies, rt->rt6i_expires));
225 static inline int rt6_need_strict(struct in6_addr *daddr)
227 return (ipv6_addr_type(daddr) &
228 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
232 * Route lookup. Any table->tb6_lock is implied.
235 static __inline__ struct rt6_info *rt6_device_match(struct rt6_info *rt,
239 struct rt6_info *local = NULL;
240 struct rt6_info *sprt;
243 for (sprt = rt; sprt; sprt = sprt->u.next) {
244 struct net_device *dev = sprt->rt6i_dev;
245 if (dev->ifindex == oif)
247 if (dev->flags & IFF_LOOPBACK) {
248 if (sprt->rt6i_idev == NULL ||
249 sprt->rt6i_idev->dev->ifindex != oif) {
252 if (local && (!oif ||
253 local->rt6i_idev->dev->ifindex == oif))
264 return &ip6_null_entry;
269 #ifdef CONFIG_IPV6_ROUTER_PREF
270 static void rt6_probe(struct rt6_info *rt)
272 struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
274 * Okay, this does not seem to be appropriate
275 * for now, however, we need to check if it
276 * is really so; aka Router Reachability Probing.
278 * Router Reachability Probe MUST be rate-limited
279 * to no more than one per minute.
281 if (!neigh || (neigh->nud_state & NUD_VALID))
283 read_lock_bh(&neigh->lock);
284 if (!(neigh->nud_state & NUD_VALID) &&
285 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
286 struct in6_addr mcaddr;
287 struct in6_addr *target;
289 neigh->updated = jiffies;
290 read_unlock_bh(&neigh->lock);
292 target = (struct in6_addr *)&neigh->primary_key;
293 addrconf_addr_solict_mult(target, &mcaddr);
294 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
296 read_unlock_bh(&neigh->lock);
299 static inline void rt6_probe(struct rt6_info *rt)
306 * Default Router Selection (RFC 2461 6.3.6)
308 static int inline rt6_check_dev(struct rt6_info *rt, int oif)
310 struct net_device *dev = rt->rt6i_dev;
311 if (!oif || dev->ifindex == oif)
313 if ((dev->flags & IFF_LOOPBACK) &&
314 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
319 static int inline rt6_check_neigh(struct rt6_info *rt)
321 struct neighbour *neigh = rt->rt6i_nexthop;
323 if (rt->rt6i_flags & RTF_NONEXTHOP ||
324 !(rt->rt6i_flags & RTF_GATEWAY))
327 read_lock_bh(&neigh->lock);
328 if (neigh->nud_state & NUD_VALID)
330 read_unlock_bh(&neigh->lock);
335 static int rt6_score_route(struct rt6_info *rt, int oif,
340 m = rt6_check_dev(rt, oif);
341 if (!m && (strict & RT6_SELECT_F_IFACE))
343 #ifdef CONFIG_IPV6_ROUTER_PREF
344 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
346 n = rt6_check_neigh(rt);
349 else if (!n && strict & RT6_SELECT_F_REACHABLE)
354 static struct rt6_info *rt6_select(struct rt6_info **head, int oif,
357 struct rt6_info *match = NULL, *last = NULL;
358 struct rt6_info *rt, *rt0 = *head;
362 RT6_TRACE("%s(head=%p(*head=%p), oif=%d)\n",
363 __FUNCTION__, head, head ? *head : NULL, oif);
365 for (rt = rt0, metric = rt0->rt6i_metric;
366 rt && rt->rt6i_metric == metric && (!last || rt != rt0);
370 if (rt6_check_expired(rt))
375 m = rt6_score_route(rt, oif, strict);
389 (strict & RT6_SELECT_F_REACHABLE) &&
390 last && last != rt0) {
391 /* no entries matched; do round-robin */
392 static DEFINE_SPINLOCK(lock);
395 rt0->u.next = last->u.next;
400 RT6_TRACE("%s() => %p, score=%d\n",
401 __FUNCTION__, match, mpri);
403 return (match ? match : &ip6_null_entry);
406 #ifdef CONFIG_IPV6_ROUTE_INFO
407 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
408 struct in6_addr *gwaddr)
410 struct route_info *rinfo = (struct route_info *) opt;
411 struct in6_addr prefix_buf, *prefix;
416 if (len < sizeof(struct route_info)) {
420 /* Sanity check for prefix_len and length */
421 if (rinfo->length > 3) {
423 } else if (rinfo->prefix_len > 128) {
425 } else if (rinfo->prefix_len > 64) {
426 if (rinfo->length < 2) {
429 } else if (rinfo->prefix_len > 0) {
430 if (rinfo->length < 1) {
435 pref = rinfo->route_pref;
436 if (pref == ICMPV6_ROUTER_PREF_INVALID)
437 pref = ICMPV6_ROUTER_PREF_MEDIUM;
439 lifetime = htonl(rinfo->lifetime);
440 if (lifetime == 0xffffffff) {
442 } else if (lifetime > 0x7fffffff/HZ) {
443 /* Avoid arithmetic overflow */
444 lifetime = 0x7fffffff/HZ - 1;
447 if (rinfo->length == 3)
448 prefix = (struct in6_addr *)rinfo->prefix;
450 /* this function is safe */
451 ipv6_addr_prefix(&prefix_buf,
452 (struct in6_addr *)rinfo->prefix,
454 prefix = &prefix_buf;
457 rt = rt6_get_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex);
459 if (rt && !lifetime) {
465 rt = rt6_add_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
468 rt->rt6i_flags = RTF_ROUTEINFO |
469 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
472 if (lifetime == 0xffffffff) {
473 rt->rt6i_flags &= ~RTF_EXPIRES;
475 rt->rt6i_expires = jiffies + HZ * lifetime;
476 rt->rt6i_flags |= RTF_EXPIRES;
478 dst_release(&rt->u.dst);
484 #define BACKTRACK() \
485 if (rt == &ip6_null_entry && flags & RT6_F_STRICT) { \
486 while ((fn = fn->parent) != NULL) { \
487 if (fn->fn_flags & RTN_TL_ROOT) { \
488 dst_hold(&rt->u.dst); \
491 if (fn->fn_flags & RTN_RTINFO) \
496 static struct rt6_info *ip6_pol_route_lookup(struct fib6_table *table,
497 struct flowi *fl, int flags)
499 struct fib6_node *fn;
502 read_lock_bh(&table->tb6_lock);
503 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
506 rt = rt6_device_match(rt, fl->oif, flags & RT6_F_STRICT);
508 dst_hold(&rt->u.dst);
510 read_unlock_bh(&table->tb6_lock);
512 rt->u.dst.lastuse = jiffies;
519 struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr,
531 struct dst_entry *dst;
532 int flags = strict ? RT6_F_STRICT : 0;
534 dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_lookup);
536 return (struct rt6_info *) dst;
543 /* ip6_ins_rt is called with FREE table->tb6_lock.
544 It takes new route entry, the addition fails by any reason the
545 route is freed. In any case, if caller does not hold it, it may
549 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
552 struct fib6_table *table;
554 table = rt->rt6i_table;
555 write_lock_bh(&table->tb6_lock);
556 err = fib6_add(&table->tb6_root, rt, info);
557 write_unlock_bh(&table->tb6_lock);
562 int ip6_ins_rt(struct rt6_info *rt)
564 return __ip6_ins_rt(rt, NULL);
567 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
568 struct in6_addr *saddr)
576 rt = ip6_rt_copy(ort);
579 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
580 if (rt->rt6i_dst.plen != 128 &&
581 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
582 rt->rt6i_flags |= RTF_ANYCAST;
583 ipv6_addr_copy(&rt->rt6i_gateway, daddr);
586 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
587 rt->rt6i_dst.plen = 128;
588 rt->rt6i_flags |= RTF_CACHE;
589 rt->u.dst.flags |= DST_HOST;
591 #ifdef CONFIG_IPV6_SUBTREES
592 if (rt->rt6i_src.plen && saddr) {
593 ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
594 rt->rt6i_src.plen = 128;
598 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
605 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
607 struct rt6_info *rt = ip6_rt_copy(ort);
609 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
610 rt->rt6i_dst.plen = 128;
611 rt->rt6i_flags |= RTF_CACHE;
612 if (rt->rt6i_flags & RTF_REJECT)
613 rt->u.dst.error = ort->u.dst.error;
614 rt->u.dst.flags |= DST_HOST;
615 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
620 static struct rt6_info *ip6_pol_route_input(struct fib6_table *table,
621 struct flowi *fl, int flags)
623 struct fib6_node *fn;
624 struct rt6_info *rt, *nrt;
628 int reachable = RT6_SELECT_F_REACHABLE;
630 if (flags & RT6_F_STRICT)
631 strict = RT6_SELECT_F_IFACE;
634 read_lock_bh(&table->tb6_lock);
637 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
640 rt = rt6_select(&fn->leaf, fl->iif, strict | reachable);
642 if (rt == &ip6_null_entry ||
643 rt->rt6i_flags & RTF_CACHE)
646 dst_hold(&rt->u.dst);
647 read_unlock_bh(&table->tb6_lock);
649 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
650 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
652 #if CLONE_OFFLINK_ROUTE
653 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
659 dst_release(&rt->u.dst);
660 rt = nrt ? : &ip6_null_entry;
662 dst_hold(&rt->u.dst);
664 err = ip6_ins_rt(nrt);
673 * Race condition! In the gap, when table->tb6_lock was
674 * released someone could insert this route. Relookup.
676 dst_release(&rt->u.dst);
684 dst_hold(&rt->u.dst);
685 read_unlock_bh(&table->tb6_lock);
687 rt->u.dst.lastuse = jiffies;
693 void ip6_route_input(struct sk_buff *skb)
695 struct ipv6hdr *iph = skb->nh.ipv6h;
697 .iif = skb->dev->ifindex,
702 .flowlabel = (* (u32 *) iph)&IPV6_FLOWINFO_MASK,
705 .proto = iph->nexthdr,
709 if (rt6_need_strict(&iph->daddr))
710 flags |= RT6_F_STRICT;
712 skb->dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_input);
715 static struct rt6_info *ip6_pol_route_output(struct fib6_table *table,
716 struct flowi *fl, int flags)
718 struct fib6_node *fn;
719 struct rt6_info *rt, *nrt;
723 int reachable = RT6_SELECT_F_REACHABLE;
725 if (flags & RT6_F_STRICT)
726 strict = RT6_SELECT_F_IFACE;
729 read_lock_bh(&table->tb6_lock);
732 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
735 rt = rt6_select(&fn->leaf, fl->oif, strict | reachable);
737 if (rt == &ip6_null_entry ||
738 rt->rt6i_flags & RTF_CACHE)
741 dst_hold(&rt->u.dst);
742 read_unlock_bh(&table->tb6_lock);
744 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
745 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
747 #if CLONE_OFFLINK_ROUTE
748 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
754 dst_release(&rt->u.dst);
755 rt = nrt ? : &ip6_null_entry;
757 dst_hold(&rt->u.dst);
759 err = ip6_ins_rt(nrt);
768 * Race condition! In the gap, when table->tb6_lock was
769 * released someone could insert this route. Relookup.
771 dst_release(&rt->u.dst);
779 dst_hold(&rt->u.dst);
780 read_unlock_bh(&table->tb6_lock);
782 rt->u.dst.lastuse = jiffies;
787 struct dst_entry * ip6_route_output(struct sock *sk, struct flowi *fl)
791 if (rt6_need_strict(&fl->fl6_dst))
792 flags |= RT6_F_STRICT;
794 return fib6_rule_lookup(fl, flags, ip6_pol_route_output);
799 * Destination cache support functions
802 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
806 rt = (struct rt6_info *) dst;
808 if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
814 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
816 struct rt6_info *rt = (struct rt6_info *) dst;
819 if (rt->rt6i_flags & RTF_CACHE)
827 static void ip6_link_failure(struct sk_buff *skb)
831 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev);
833 rt = (struct rt6_info *) skb->dst;
835 if (rt->rt6i_flags&RTF_CACHE) {
836 dst_set_expires(&rt->u.dst, 0);
837 rt->rt6i_flags |= RTF_EXPIRES;
838 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
839 rt->rt6i_node->fn_sernum = -1;
843 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
845 struct rt6_info *rt6 = (struct rt6_info*)dst;
847 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
848 rt6->rt6i_flags |= RTF_MODIFIED;
849 if (mtu < IPV6_MIN_MTU) {
851 dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
853 dst->metrics[RTAX_MTU-1] = mtu;
854 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
858 static int ipv6_get_mtu(struct net_device *dev);
860 static inline unsigned int ipv6_advmss(unsigned int mtu)
862 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
864 if (mtu < ip6_rt_min_advmss)
865 mtu = ip6_rt_min_advmss;
868 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
869 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
870 * IPV6_MAXPLEN is also valid and means: "any MSS,
871 * rely only on pmtu discovery"
873 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
878 static struct dst_entry *ndisc_dst_gc_list;
879 static DEFINE_SPINLOCK(ndisc_lock);
881 struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
882 struct neighbour *neigh,
883 struct in6_addr *addr,
884 int (*output)(struct sk_buff *))
887 struct inet6_dev *idev = in6_dev_get(dev);
889 if (unlikely(idev == NULL))
892 rt = ip6_dst_alloc();
893 if (unlikely(rt == NULL)) {
902 neigh = ndisc_get_neigh(dev, addr);
905 rt->rt6i_idev = idev;
906 rt->rt6i_nexthop = neigh;
907 atomic_set(&rt->u.dst.__refcnt, 1);
908 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
909 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
910 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
911 rt->u.dst.output = output;
913 #if 0 /* there's no chance to use these for ndisc */
914 rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
917 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
918 rt->rt6i_dst.plen = 128;
921 spin_lock_bh(&ndisc_lock);
922 rt->u.dst.next = ndisc_dst_gc_list;
923 ndisc_dst_gc_list = &rt->u.dst;
924 spin_unlock_bh(&ndisc_lock);
926 fib6_force_start_gc();
929 return (struct dst_entry *)rt;
932 int ndisc_dst_gc(int *more)
934 struct dst_entry *dst, *next, **pprev;
940 spin_lock_bh(&ndisc_lock);
941 pprev = &ndisc_dst_gc_list;
943 while ((dst = *pprev) != NULL) {
944 if (!atomic_read(&dst->__refcnt)) {
954 spin_unlock_bh(&ndisc_lock);
959 static int ip6_dst_gc(void)
961 static unsigned expire = 30*HZ;
962 static unsigned long last_gc;
963 unsigned long now = jiffies;
965 if (time_after(last_gc + ip6_rt_gc_min_interval, now) &&
966 atomic_read(&ip6_dst_ops.entries) <= ip6_rt_max_size)
972 if (atomic_read(&ip6_dst_ops.entries) < ip6_dst_ops.gc_thresh)
973 expire = ip6_rt_gc_timeout>>1;
976 expire -= expire>>ip6_rt_gc_elasticity;
977 return (atomic_read(&ip6_dst_ops.entries) > ip6_rt_max_size);
980 /* Clean host part of a prefix. Not necessary in radix tree,
981 but results in cleaner routing tables.
983 Remove it only when all the things will work!
986 static int ipv6_get_mtu(struct net_device *dev)
988 int mtu = IPV6_MIN_MTU;
989 struct inet6_dev *idev;
991 idev = in6_dev_get(dev);
993 mtu = idev->cnf.mtu6;
999 int ipv6_get_hoplimit(struct net_device *dev)
1001 int hoplimit = ipv6_devconf.hop_limit;
1002 struct inet6_dev *idev;
1004 idev = in6_dev_get(dev);
1006 hoplimit = idev->cnf.hop_limit;
1016 int ip6_route_add(struct fib6_config *cfg)
1019 struct rt6_info *rt = NULL;
1020 struct net_device *dev = NULL;
1021 struct inet6_dev *idev = NULL;
1022 struct fib6_table *table;
1025 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1027 #ifndef CONFIG_IPV6_SUBTREES
1028 if (cfg->fc_src_len)
1031 if (cfg->fc_ifindex) {
1033 dev = dev_get_by_index(cfg->fc_ifindex);
1036 idev = in6_dev_get(dev);
1041 if (cfg->fc_metric == 0)
1042 cfg->fc_metric = IP6_RT_PRIO_USER;
1044 table = fib6_new_table(cfg->fc_table);
1045 if (table == NULL) {
1050 rt = ip6_dst_alloc();
1057 rt->u.dst.obsolete = -1;
1058 rt->rt6i_expires = jiffies + clock_t_to_jiffies(cfg->fc_expires);
1060 if (cfg->fc_protocol == RTPROT_UNSPEC)
1061 cfg->fc_protocol = RTPROT_BOOT;
1062 rt->rt6i_protocol = cfg->fc_protocol;
1064 addr_type = ipv6_addr_type(&cfg->fc_dst);
1066 if (addr_type & IPV6_ADDR_MULTICAST)
1067 rt->u.dst.input = ip6_mc_input;
1069 rt->u.dst.input = ip6_forward;
1071 rt->u.dst.output = ip6_output;
1073 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1074 rt->rt6i_dst.plen = cfg->fc_dst_len;
1075 if (rt->rt6i_dst.plen == 128)
1076 rt->u.dst.flags = DST_HOST;
1078 #ifdef CONFIG_IPV6_SUBTREES
1079 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1080 rt->rt6i_src.plen = cfg->fc_src_len;
1083 rt->rt6i_metric = cfg->fc_metric;
1085 /* We cannot add true routes via loopback here,
1086 they would result in kernel looping; promote them to reject routes
1088 if ((cfg->fc_flags & RTF_REJECT) ||
1089 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
1090 /* hold loopback dev/idev if we haven't done so. */
1091 if (dev != &loopback_dev) {
1096 dev = &loopback_dev;
1098 idev = in6_dev_get(dev);
1104 rt->u.dst.output = ip6_pkt_discard_out;
1105 rt->u.dst.input = ip6_pkt_discard;
1106 rt->u.dst.error = -ENETUNREACH;
1107 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1111 if (cfg->fc_flags & RTF_GATEWAY) {
1112 struct in6_addr *gw_addr;
1115 gw_addr = &cfg->fc_gateway;
1116 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1117 gwa_type = ipv6_addr_type(gw_addr);
1119 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1120 struct rt6_info *grt;
1122 /* IPv6 strictly inhibits using not link-local
1123 addresses as nexthop address.
1124 Otherwise, router will not able to send redirects.
1125 It is very good, but in some (rare!) circumstances
1126 (SIT, PtP, NBMA NOARP links) it is handy to allow
1127 some exceptions. --ANK
1130 if (!(gwa_type&IPV6_ADDR_UNICAST))
1133 grt = rt6_lookup(gw_addr, NULL, cfg->fc_ifindex, 1);
1135 err = -EHOSTUNREACH;
1139 if (dev != grt->rt6i_dev) {
1140 dst_release(&grt->u.dst);
1144 dev = grt->rt6i_dev;
1145 idev = grt->rt6i_idev;
1147 in6_dev_hold(grt->rt6i_idev);
1149 if (!(grt->rt6i_flags&RTF_GATEWAY))
1151 dst_release(&grt->u.dst);
1157 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1165 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1166 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1167 if (IS_ERR(rt->rt6i_nexthop)) {
1168 err = PTR_ERR(rt->rt6i_nexthop);
1169 rt->rt6i_nexthop = NULL;
1174 rt->rt6i_flags = cfg->fc_flags;
1181 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1182 int type = nla->nla_type;
1185 if (type > RTAX_MAX) {
1190 rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
1195 if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0)
1196 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1197 if (!rt->u.dst.metrics[RTAX_MTU-1])
1198 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
1199 if (!rt->u.dst.metrics[RTAX_ADVMSS-1])
1200 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1201 rt->u.dst.dev = dev;
1202 rt->rt6i_idev = idev;
1203 rt->rt6i_table = table;
1204 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1212 dst_free((struct dst_entry *) rt);
1216 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1219 struct fib6_table *table;
1221 if (rt == &ip6_null_entry)
1224 table = rt->rt6i_table;
1225 write_lock_bh(&table->tb6_lock);
1227 err = fib6_del(rt, info);
1228 dst_release(&rt->u.dst);
1230 write_unlock_bh(&table->tb6_lock);
1235 int ip6_del_rt(struct rt6_info *rt)
1237 return __ip6_del_rt(rt, NULL);
1240 static int ip6_route_del(struct fib6_config *cfg)
1242 struct fib6_table *table;
1243 struct fib6_node *fn;
1244 struct rt6_info *rt;
1247 table = fib6_get_table(cfg->fc_table);
1251 read_lock_bh(&table->tb6_lock);
1253 fn = fib6_locate(&table->tb6_root,
1254 &cfg->fc_dst, cfg->fc_dst_len,
1255 &cfg->fc_src, cfg->fc_src_len);
1258 for (rt = fn->leaf; rt; rt = rt->u.next) {
1259 if (cfg->fc_ifindex &&
1260 (rt->rt6i_dev == NULL ||
1261 rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1263 if (cfg->fc_flags & RTF_GATEWAY &&
1264 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1266 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1268 dst_hold(&rt->u.dst);
1269 read_unlock_bh(&table->tb6_lock);
1271 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1274 read_unlock_bh(&table->tb6_lock);
1282 void rt6_redirect(struct in6_addr *dest, struct in6_addr *saddr,
1283 struct neighbour *neigh, u8 *lladdr, int on_link)
1285 struct rt6_info *rt, *nrt = NULL;
1286 struct fib6_node *fn;
1287 struct fib6_table *table;
1288 struct netevent_redirect netevent;
1290 /* TODO: Very lazy, might need to check all tables */
1291 table = fib6_get_table(RT6_TABLE_MAIN);
1296 * Get the "current" route for this destination and
1297 * check if the redirect has come from approriate router.
1299 * RFC 2461 specifies that redirects should only be
1300 * accepted if they come from the nexthop to the target.
1301 * Due to the way the routes are chosen, this notion
1302 * is a bit fuzzy and one might need to check all possible
1306 read_lock_bh(&table->tb6_lock);
1307 fn = fib6_lookup(&table->tb6_root, dest, NULL);
1309 for (rt = fn->leaf; rt; rt = rt->u.next) {
1311 * Current route is on-link; redirect is always invalid.
1313 * Seems, previous statement is not true. It could
1314 * be node, which looks for us as on-link (f.e. proxy ndisc)
1315 * But then router serving it might decide, that we should
1316 * know truth 8)8) --ANK (980726).
1318 if (rt6_check_expired(rt))
1320 if (!(rt->rt6i_flags & RTF_GATEWAY))
1322 if (neigh->dev != rt->rt6i_dev)
1324 if (!ipv6_addr_equal(saddr, &rt->rt6i_gateway))
1329 dst_hold(&rt->u.dst);
1330 else if (rt6_need_strict(dest)) {
1331 while ((fn = fn->parent) != NULL) {
1332 if (fn->fn_flags & RTN_ROOT)
1334 if (fn->fn_flags & RTN_RTINFO)
1338 read_unlock_bh(&table->tb6_lock);
1341 if (net_ratelimit())
1342 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1343 "for redirect target\n");
1348 * We have finally decided to accept it.
1351 neigh_update(neigh, lladdr, NUD_STALE,
1352 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1353 NEIGH_UPDATE_F_OVERRIDE|
1354 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1355 NEIGH_UPDATE_F_ISROUTER))
1359 * Redirect received -> path was valid.
1360 * Look, redirects are sent only in response to data packets,
1361 * so that this nexthop apparently is reachable. --ANK
1363 dst_confirm(&rt->u.dst);
1365 /* Duplicate redirect: silently ignore. */
1366 if (neigh == rt->u.dst.neighbour)
1369 nrt = ip6_rt_copy(rt);
1373 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1375 nrt->rt6i_flags &= ~RTF_GATEWAY;
1377 ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1378 nrt->rt6i_dst.plen = 128;
1379 nrt->u.dst.flags |= DST_HOST;
1381 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1382 nrt->rt6i_nexthop = neigh_clone(neigh);
1383 /* Reset pmtu, it may be better */
1384 nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
1385 nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&nrt->u.dst));
1387 if (ip6_ins_rt(nrt))
1390 netevent.old = &rt->u.dst;
1391 netevent.new = &nrt->u.dst;
1392 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1394 if (rt->rt6i_flags&RTF_CACHE) {
1400 dst_release(&rt->u.dst);
1405 * Handle ICMP "packet too big" messages
1406 * i.e. Path MTU discovery
1409 void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
1410 struct net_device *dev, u32 pmtu)
1412 struct rt6_info *rt, *nrt;
1415 rt = rt6_lookup(daddr, saddr, dev->ifindex, 0);
1419 if (pmtu >= dst_mtu(&rt->u.dst))
1422 if (pmtu < IPV6_MIN_MTU) {
1424 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1425 * MTU (1280) and a fragment header should always be included
1426 * after a node receiving Too Big message reporting PMTU is
1427 * less than the IPv6 Minimum Link MTU.
1429 pmtu = IPV6_MIN_MTU;
1433 /* New mtu received -> path was valid.
1434 They are sent only in response to data packets,
1435 so that this nexthop apparently is reachable. --ANK
1437 dst_confirm(&rt->u.dst);
1439 /* Host route. If it is static, it would be better
1440 not to override it, but add new one, so that
1441 when cache entry will expire old pmtu
1442 would return automatically.
1444 if (rt->rt6i_flags & RTF_CACHE) {
1445 rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1447 rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1448 dst_set_expires(&rt->u.dst, ip6_rt_mtu_expires);
1449 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1454 Two cases are possible:
1455 1. It is connected route. Action: COW
1456 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1458 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1459 nrt = rt6_alloc_cow(rt, daddr, saddr);
1461 nrt = rt6_alloc_clone(rt, daddr);
1464 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1466 nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1468 /* According to RFC 1981, detecting PMTU increase shouldn't be
1469 * happened within 5 mins, the recommended timer is 10 mins.
1470 * Here this route expiration time is set to ip6_rt_mtu_expires
1471 * which is 10 mins. After 10 mins the decreased pmtu is expired
1472 * and detecting PMTU increase will be automatically happened.
1474 dst_set_expires(&nrt->u.dst, ip6_rt_mtu_expires);
1475 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1480 dst_release(&rt->u.dst);
1484 * Misc support functions
1487 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1489 struct rt6_info *rt = ip6_dst_alloc();
1492 rt->u.dst.input = ort->u.dst.input;
1493 rt->u.dst.output = ort->u.dst.output;
1495 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1496 rt->u.dst.dev = ort->u.dst.dev;
1498 dev_hold(rt->u.dst.dev);
1499 rt->rt6i_idev = ort->rt6i_idev;
1501 in6_dev_hold(rt->rt6i_idev);
1502 rt->u.dst.lastuse = jiffies;
1503 rt->rt6i_expires = 0;
1505 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1506 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1507 rt->rt6i_metric = 0;
1509 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1510 #ifdef CONFIG_IPV6_SUBTREES
1511 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1513 rt->rt6i_table = ort->rt6i_table;
1518 #ifdef CONFIG_IPV6_ROUTE_INFO
1519 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
1520 struct in6_addr *gwaddr, int ifindex)
1522 struct fib6_node *fn;
1523 struct rt6_info *rt = NULL;
1524 struct fib6_table *table;
1526 table = fib6_get_table(RT6_TABLE_INFO);
1530 write_lock_bh(&table->tb6_lock);
1531 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1535 for (rt = fn->leaf; rt; rt = rt->u.next) {
1536 if (rt->rt6i_dev->ifindex != ifindex)
1538 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1540 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1542 dst_hold(&rt->u.dst);
1546 write_unlock_bh(&table->tb6_lock);
1550 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
1551 struct in6_addr *gwaddr, int ifindex,
1554 struct fib6_config cfg = {
1555 .fc_table = RT6_TABLE_INFO,
1557 .fc_ifindex = ifindex,
1558 .fc_dst_len = prefixlen,
1559 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1560 RTF_UP | RTF_PREF(pref),
1563 ipv6_addr_copy(&cfg.fc_dst, prefix);
1564 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1566 /* We should treat it as a default route if prefix length is 0. */
1568 cfg.fc_flags |= RTF_DEFAULT;
1570 ip6_route_add(&cfg);
1572 return rt6_get_route_info(prefix, prefixlen, gwaddr, ifindex);
1576 struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1578 struct rt6_info *rt;
1579 struct fib6_table *table;
1581 table = fib6_get_table(RT6_TABLE_DFLT);
1585 write_lock_bh(&table->tb6_lock);
1586 for (rt = table->tb6_root.leaf; rt; rt=rt->u.next) {
1587 if (dev == rt->rt6i_dev &&
1588 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1589 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1593 dst_hold(&rt->u.dst);
1594 write_unlock_bh(&table->tb6_lock);
1598 struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1599 struct net_device *dev,
1602 struct fib6_config cfg = {
1603 .fc_table = RT6_TABLE_DFLT,
1605 .fc_ifindex = dev->ifindex,
1606 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1607 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1610 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1612 ip6_route_add(&cfg);
1614 return rt6_get_dflt_router(gwaddr, dev);
1617 void rt6_purge_dflt_routers(void)
1619 struct rt6_info *rt;
1620 struct fib6_table *table;
1622 /* NOTE: Keep consistent with rt6_get_dflt_router */
1623 table = fib6_get_table(RT6_TABLE_DFLT);
1628 read_lock_bh(&table->tb6_lock);
1629 for (rt = table->tb6_root.leaf; rt; rt = rt->u.next) {
1630 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1631 dst_hold(&rt->u.dst);
1632 read_unlock_bh(&table->tb6_lock);
1637 read_unlock_bh(&table->tb6_lock);
1640 static void rtmsg_to_fib6_config(struct in6_rtmsg *rtmsg,
1641 struct fib6_config *cfg)
1643 memset(cfg, 0, sizeof(*cfg));
1645 cfg->fc_table = RT6_TABLE_MAIN;
1646 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1647 cfg->fc_metric = rtmsg->rtmsg_metric;
1648 cfg->fc_expires = rtmsg->rtmsg_info;
1649 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1650 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1651 cfg->fc_flags = rtmsg->rtmsg_flags;
1653 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1654 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1655 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1658 int ipv6_route_ioctl(unsigned int cmd, void __user *arg)
1660 struct fib6_config cfg;
1661 struct in6_rtmsg rtmsg;
1665 case SIOCADDRT: /* Add a route */
1666 case SIOCDELRT: /* Delete a route */
1667 if (!capable(CAP_NET_ADMIN))
1669 err = copy_from_user(&rtmsg, arg,
1670 sizeof(struct in6_rtmsg));
1674 rtmsg_to_fib6_config(&rtmsg, &cfg);
1679 err = ip6_route_add(&cfg);
1682 err = ip6_route_del(&cfg);
1696 * Drop the packet on the floor
1699 static int ip6_pkt_discard(struct sk_buff *skb)
1701 int type = ipv6_addr_type(&skb->nh.ipv6h->daddr);
1702 if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED)
1703 IP6_INC_STATS(IPSTATS_MIB_INADDRERRORS);
1705 IP6_INC_STATS(IPSTATS_MIB_OUTNOROUTES);
1706 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_NOROUTE, 0, skb->dev);
1711 static int ip6_pkt_discard_out(struct sk_buff *skb)
1713 skb->dev = skb->dst->dev;
1714 return ip6_pkt_discard(skb);
1718 * Allocate a dst for local (unicast / anycast) address.
1721 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
1722 const struct in6_addr *addr,
1725 struct rt6_info *rt = ip6_dst_alloc();
1728 return ERR_PTR(-ENOMEM);
1730 dev_hold(&loopback_dev);
1733 rt->u.dst.flags = DST_HOST;
1734 rt->u.dst.input = ip6_input;
1735 rt->u.dst.output = ip6_output;
1736 rt->rt6i_dev = &loopback_dev;
1737 rt->rt6i_idev = idev;
1738 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1739 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1740 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1741 rt->u.dst.obsolete = -1;
1743 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1745 rt->rt6i_flags |= RTF_ANYCAST;
1747 rt->rt6i_flags |= RTF_LOCAL;
1748 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
1749 if (rt->rt6i_nexthop == NULL) {
1750 dst_free((struct dst_entry *) rt);
1751 return ERR_PTR(-ENOMEM);
1754 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1755 rt->rt6i_dst.plen = 128;
1756 rt->rt6i_table = fib6_get_table(RT6_TABLE_LOCAL);
1758 atomic_set(&rt->u.dst.__refcnt, 1);
1763 static int fib6_ifdown(struct rt6_info *rt, void *arg)
1765 if (((void*)rt->rt6i_dev == arg || arg == NULL) &&
1766 rt != &ip6_null_entry) {
1767 RT6_TRACE("deleted by ifdown %p\n", rt);
1773 void rt6_ifdown(struct net_device *dev)
1775 fib6_clean_all(fib6_ifdown, 0, dev);
1778 struct rt6_mtu_change_arg
1780 struct net_device *dev;
1784 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
1786 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
1787 struct inet6_dev *idev;
1789 /* In IPv6 pmtu discovery is not optional,
1790 so that RTAX_MTU lock cannot disable it.
1791 We still use this lock to block changes
1792 caused by addrconf/ndisc.
1795 idev = __in6_dev_get(arg->dev);
1799 /* For administrative MTU increase, there is no way to discover
1800 IPv6 PMTU increase, so PMTU increase should be updated here.
1801 Since RFC 1981 doesn't include administrative MTU increase
1802 update PMTU increase is a MUST. (i.e. jumbo frame)
1805 If new MTU is less than route PMTU, this new MTU will be the
1806 lowest MTU in the path, update the route PMTU to reflect PMTU
1807 decreases; if new MTU is greater than route PMTU, and the
1808 old MTU is the lowest MTU in the path, update the route PMTU
1809 to reflect the increase. In this case if the other nodes' MTU
1810 also have the lowest MTU, TOO BIG MESSAGE will be lead to
1813 if (rt->rt6i_dev == arg->dev &&
1814 !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1815 (dst_mtu(&rt->u.dst) > arg->mtu ||
1816 (dst_mtu(&rt->u.dst) < arg->mtu &&
1817 dst_mtu(&rt->u.dst) == idev->cnf.mtu6)))
1818 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
1819 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(arg->mtu);
1823 void rt6_mtu_change(struct net_device *dev, unsigned mtu)
1825 struct rt6_mtu_change_arg arg = {
1830 fib6_clean_all(rt6_mtu_change_route, 0, &arg);
1833 static struct nla_policy rtm_ipv6_policy[RTA_MAX+1] __read_mostly = {
1834 [RTA_GATEWAY] = { .minlen = sizeof(struct in6_addr) },
1835 [RTA_OIF] = { .type = NLA_U32 },
1836 [RTA_IIF] = { .type = NLA_U32 },
1837 [RTA_PRIORITY] = { .type = NLA_U32 },
1838 [RTA_METRICS] = { .type = NLA_NESTED },
1841 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
1842 struct fib6_config *cfg)
1845 struct nlattr *tb[RTA_MAX+1];
1848 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
1853 rtm = nlmsg_data(nlh);
1854 memset(cfg, 0, sizeof(*cfg));
1856 cfg->fc_table = rtm->rtm_table;
1857 cfg->fc_dst_len = rtm->rtm_dst_len;
1858 cfg->fc_src_len = rtm->rtm_src_len;
1859 cfg->fc_flags = RTF_UP;
1860 cfg->fc_protocol = rtm->rtm_protocol;
1862 if (rtm->rtm_type == RTN_UNREACHABLE)
1863 cfg->fc_flags |= RTF_REJECT;
1865 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
1866 cfg->fc_nlinfo.nlh = nlh;
1868 if (tb[RTA_GATEWAY]) {
1869 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
1870 cfg->fc_flags |= RTF_GATEWAY;
1874 int plen = (rtm->rtm_dst_len + 7) >> 3;
1876 if (nla_len(tb[RTA_DST]) < plen)
1879 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
1883 int plen = (rtm->rtm_src_len + 7) >> 3;
1885 if (nla_len(tb[RTA_SRC]) < plen)
1888 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
1892 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
1894 if (tb[RTA_PRIORITY])
1895 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
1897 if (tb[RTA_METRICS]) {
1898 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
1899 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
1903 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
1910 int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
1912 struct fib6_config cfg;
1915 err = rtm_to_fib6_config(skb, nlh, &cfg);
1919 return ip6_route_del(&cfg);
1922 int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
1924 struct fib6_config cfg;
1927 err = rtm_to_fib6_config(skb, nlh, &cfg);
1931 return ip6_route_add(&cfg);
1934 static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
1935 struct in6_addr *dst, struct in6_addr *src,
1936 int iif, int type, u32 pid, u32 seq,
1937 int prefix, unsigned int flags)
1940 struct nlmsghdr *nlh;
1941 struct rta_cacheinfo ci;
1944 if (prefix) { /* user wants prefix routes only */
1945 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
1946 /* success since this is not a prefix route */
1951 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
1955 rtm = nlmsg_data(nlh);
1956 rtm->rtm_family = AF_INET6;
1957 rtm->rtm_dst_len = rt->rt6i_dst.plen;
1958 rtm->rtm_src_len = rt->rt6i_src.plen;
1961 table = rt->rt6i_table->tb6_id;
1963 table = RT6_TABLE_UNSPEC;
1964 rtm->rtm_table = table;
1965 NLA_PUT_U32(skb, RTA_TABLE, table);
1966 if (rt->rt6i_flags&RTF_REJECT)
1967 rtm->rtm_type = RTN_UNREACHABLE;
1968 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
1969 rtm->rtm_type = RTN_LOCAL;
1971 rtm->rtm_type = RTN_UNICAST;
1973 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
1974 rtm->rtm_protocol = rt->rt6i_protocol;
1975 if (rt->rt6i_flags&RTF_DYNAMIC)
1976 rtm->rtm_protocol = RTPROT_REDIRECT;
1977 else if (rt->rt6i_flags & RTF_ADDRCONF)
1978 rtm->rtm_protocol = RTPROT_KERNEL;
1979 else if (rt->rt6i_flags&RTF_DEFAULT)
1980 rtm->rtm_protocol = RTPROT_RA;
1982 if (rt->rt6i_flags&RTF_CACHE)
1983 rtm->rtm_flags |= RTM_F_CLONED;
1986 NLA_PUT(skb, RTA_DST, 16, dst);
1987 rtm->rtm_dst_len = 128;
1988 } else if (rtm->rtm_dst_len)
1989 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
1990 #ifdef CONFIG_IPV6_SUBTREES
1992 NLA_PUT(skb, RTA_SRC, 16, src);
1993 rtm->rtm_src_len = 128;
1994 } else if (rtm->rtm_src_len)
1995 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
1998 NLA_PUT_U32(skb, RTA_IIF, iif);
2000 struct in6_addr saddr_buf;
2001 if (ipv6_get_saddr(&rt->u.dst, dst, &saddr_buf) == 0)
2002 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2005 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2006 goto nla_put_failure;
2008 if (rt->u.dst.neighbour)
2009 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);
2012 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2014 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2015 ci.rta_lastuse = jiffies_to_clock_t(jiffies - rt->u.dst.lastuse);
2016 if (rt->rt6i_expires)
2017 ci.rta_expires = jiffies_to_clock_t(rt->rt6i_expires - jiffies);
2020 ci.rta_used = rt->u.dst.__use;
2021 ci.rta_clntref = atomic_read(&rt->u.dst.__refcnt);
2022 ci.rta_error = rt->u.dst.error;
2026 NLA_PUT(skb, RTA_CACHEINFO, sizeof(ci), &ci);
2028 return nlmsg_end(skb, nlh);
2031 return nlmsg_cancel(skb, nlh);
2034 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2036 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2039 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2040 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2041 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2045 return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2046 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2047 prefix, NLM_F_MULTI);
2050 int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2052 struct nlattr *tb[RTA_MAX+1];
2053 struct rt6_info *rt;
2054 struct sk_buff *skb;
2059 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2064 memset(&fl, 0, sizeof(fl));
2067 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2070 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
2074 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2077 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
2081 iif = nla_get_u32(tb[RTA_IIF]);
2084 fl.oif = nla_get_u32(tb[RTA_OIF]);
2087 struct net_device *dev;
2088 dev = __dev_get_by_index(iif);
2095 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2101 /* Reserve room for dummy headers, this skb can pass
2102 through good chunk of routing engine.
2104 skb->mac.raw = skb->data;
2105 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2107 rt = (struct rt6_info*) ip6_route_output(NULL, &fl);
2108 skb->dst = &rt->u.dst;
2110 err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
2111 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2112 nlh->nlmsg_seq, 0, 0);
2118 err = rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
2123 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2125 struct sk_buff *skb;
2126 u32 pid = 0, seq = 0;
2127 struct nlmsghdr *nlh = NULL;
2128 int payload = sizeof(struct rtmsg) + 256;
2135 seq = nlh->nlmsg_seq;
2138 skb = nlmsg_new(nlmsg_total_size(payload), gfp_any());
2142 err = rt6_fill_node(skb, rt, NULL, NULL, 0, event, pid, seq, 0, 0);
2148 err = rtnl_notify(skb, pid, RTNLGRP_IPV6_ROUTE, nlh, gfp_any());
2151 rtnl_set_sk_err(RTNLGRP_IPV6_ROUTE, err);
2158 #ifdef CONFIG_PROC_FS
2160 #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)
2171 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2173 struct rt6_proc_arg *arg = (struct rt6_proc_arg *) p_arg;
2176 if (arg->skip < arg->offset / RT6_INFO_LEN) {
2181 if (arg->len >= arg->length)
2184 for (i=0; i<16; i++) {
2185 sprintf(arg->buffer + arg->len, "%02x",
2186 rt->rt6i_dst.addr.s6_addr[i]);
2189 arg->len += sprintf(arg->buffer + arg->len, " %02x ",
2192 #ifdef CONFIG_IPV6_SUBTREES
2193 for (i=0; i<16; i++) {
2194 sprintf(arg->buffer + arg->len, "%02x",
2195 rt->rt6i_src.addr.s6_addr[i]);
2198 arg->len += sprintf(arg->buffer + arg->len, " %02x ",
2201 sprintf(arg->buffer + arg->len,
2202 "00000000000000000000000000000000 00 ");
2206 if (rt->rt6i_nexthop) {
2207 for (i=0; i<16; i++) {
2208 sprintf(arg->buffer + arg->len, "%02x",
2209 rt->rt6i_nexthop->primary_key[i]);
2213 sprintf(arg->buffer + arg->len,
2214 "00000000000000000000000000000000");
2217 arg->len += sprintf(arg->buffer + arg->len,
2218 " %08x %08x %08x %08x %8s\n",
2219 rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2220 rt->u.dst.__use, rt->rt6i_flags,
2221 rt->rt6i_dev ? rt->rt6i_dev->name : "");
2225 static int rt6_proc_info(char *buffer, char **start, off_t offset, int length)
2227 struct rt6_proc_arg arg = {
2233 fib6_clean_all(rt6_info_route, 0, &arg);
2237 *start += offset % RT6_INFO_LEN;
2239 arg.len -= offset % RT6_INFO_LEN;
2241 if (arg.len > length)
2249 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2251 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2252 rt6_stats.fib_nodes, rt6_stats.fib_route_nodes,
2253 rt6_stats.fib_rt_alloc, rt6_stats.fib_rt_entries,
2254 rt6_stats.fib_rt_cache,
2255 atomic_read(&ip6_dst_ops.entries),
2256 rt6_stats.fib_discarded_routes);
2261 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2263 return single_open(file, rt6_stats_seq_show, NULL);
2266 static struct file_operations rt6_stats_seq_fops = {
2267 .owner = THIS_MODULE,
2268 .open = rt6_stats_seq_open,
2270 .llseek = seq_lseek,
2271 .release = single_release,
2273 #endif /* CONFIG_PROC_FS */
2275 #ifdef CONFIG_SYSCTL
2277 static int flush_delay;
2280 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp,
2281 void __user *buffer, size_t *lenp, loff_t *ppos)
2284 proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
2285 fib6_run_gc(flush_delay <= 0 ? ~0UL : (unsigned long)flush_delay);
2291 ctl_table ipv6_route_table[] = {
2293 .ctl_name = NET_IPV6_ROUTE_FLUSH,
2294 .procname = "flush",
2295 .data = &flush_delay,
2296 .maxlen = sizeof(int),
2298 .proc_handler = &ipv6_sysctl_rtcache_flush
2301 .ctl_name = NET_IPV6_ROUTE_GC_THRESH,
2302 .procname = "gc_thresh",
2303 .data = &ip6_dst_ops.gc_thresh,
2304 .maxlen = sizeof(int),
2306 .proc_handler = &proc_dointvec,
2309 .ctl_name = NET_IPV6_ROUTE_MAX_SIZE,
2310 .procname = "max_size",
2311 .data = &ip6_rt_max_size,
2312 .maxlen = sizeof(int),
2314 .proc_handler = &proc_dointvec,
2317 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL,
2318 .procname = "gc_min_interval",
2319 .data = &ip6_rt_gc_min_interval,
2320 .maxlen = sizeof(int),
2322 .proc_handler = &proc_dointvec_jiffies,
2323 .strategy = &sysctl_jiffies,
2326 .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT,
2327 .procname = "gc_timeout",
2328 .data = &ip6_rt_gc_timeout,
2329 .maxlen = sizeof(int),
2331 .proc_handler = &proc_dointvec_jiffies,
2332 .strategy = &sysctl_jiffies,
2335 .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL,
2336 .procname = "gc_interval",
2337 .data = &ip6_rt_gc_interval,
2338 .maxlen = sizeof(int),
2340 .proc_handler = &proc_dointvec_jiffies,
2341 .strategy = &sysctl_jiffies,
2344 .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY,
2345 .procname = "gc_elasticity",
2346 .data = &ip6_rt_gc_elasticity,
2347 .maxlen = sizeof(int),
2349 .proc_handler = &proc_dointvec_jiffies,
2350 .strategy = &sysctl_jiffies,
2353 .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES,
2354 .procname = "mtu_expires",
2355 .data = &ip6_rt_mtu_expires,
2356 .maxlen = sizeof(int),
2358 .proc_handler = &proc_dointvec_jiffies,
2359 .strategy = &sysctl_jiffies,
2362 .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS,
2363 .procname = "min_adv_mss",
2364 .data = &ip6_rt_min_advmss,
2365 .maxlen = sizeof(int),
2367 .proc_handler = &proc_dointvec_jiffies,
2368 .strategy = &sysctl_jiffies,
2371 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS,
2372 .procname = "gc_min_interval_ms",
2373 .data = &ip6_rt_gc_min_interval,
2374 .maxlen = sizeof(int),
2376 .proc_handler = &proc_dointvec_ms_jiffies,
2377 .strategy = &sysctl_ms_jiffies,
2384 void __init ip6_route_init(void)
2386 struct proc_dir_entry *p;
2388 ip6_dst_ops.kmem_cachep = kmem_cache_create("ip6_dst_cache",
2389 sizeof(struct rt6_info),
2390 0, SLAB_HWCACHE_ALIGN,
2392 if (!ip6_dst_ops.kmem_cachep)
2393 panic("cannot create ip6_dst_cache");
2396 #ifdef CONFIG_PROC_FS
2397 p = proc_net_create("ipv6_route", 0, rt6_proc_info);
2399 p->owner = THIS_MODULE;
2401 proc_net_fops_create("rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2406 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2411 void ip6_route_cleanup(void)
2413 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2414 fib6_rules_cleanup();
2416 #ifdef CONFIG_PROC_FS
2417 proc_net_remove("ipv6_route");
2418 proc_net_remove("rt6_stats");
2425 kmem_cache_destroy(ip6_dst_ops.kmem_cachep);