ACPI: thinkpad-acpi: add a safety net for TPEC fan control mode
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv6 / route.c
blob01bcf4ab1446f6fa8b8f9ee4e10753fcfeed65da
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>
42 #ifdef CONFIG_PROC_FS
43 #include <linux/proc_fs.h>
44 #include <linux/seq_file.h>
45 #endif
47 #include <net/snmp.h>
48 #include <net/ipv6.h>
49 #include <net/ip6_fib.h>
50 #include <net/ip6_route.h>
51 #include <net/ndisc.h>
52 #include <net/addrconf.h>
53 #include <net/tcp.h>
54 #include <linux/rtnetlink.h>
55 #include <net/dst.h>
56 #include <net/xfrm.h>
57 #include <net/netevent.h>
58 #include <net/netlink.h>
60 #include <asm/uaccess.h>
62 #ifdef CONFIG_SYSCTL
63 #include <linux/sysctl.h>
64 #endif
66 /* Set to 3 to get tracing. */
67 #define RT6_DEBUG 2
69 #if RT6_DEBUG >= 3
70 #define RDBG(x) printk x
71 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
72 #else
73 #define RDBG(x)
74 #define RT6_TRACE(x...) do { ; } while (0)
75 #endif
77 #define CLONE_OFFLINK_ROUTE 0
79 static int ip6_rt_max_size = 4096;
80 static int ip6_rt_gc_min_interval = HZ / 2;
81 static int ip6_rt_gc_timeout = 60*HZ;
82 int ip6_rt_gc_interval = 30*HZ;
83 static int ip6_rt_gc_elasticity = 9;
84 static int ip6_rt_mtu_expires = 10*60*HZ;
85 static int ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
87 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
88 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
89 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
90 static void ip6_dst_destroy(struct dst_entry *);
91 static void ip6_dst_ifdown(struct dst_entry *,
92 struct net_device *dev, int how);
93 static int ip6_dst_gc(void);
95 static int ip6_pkt_discard(struct sk_buff *skb);
96 static int ip6_pkt_discard_out(struct sk_buff *skb);
97 static void ip6_link_failure(struct sk_buff *skb);
98 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
100 #ifdef CONFIG_IPV6_ROUTE_INFO
101 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
102 struct in6_addr *gwaddr, int ifindex,
103 unsigned pref);
104 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
105 struct in6_addr *gwaddr, int ifindex);
106 #endif
108 static struct dst_ops ip6_dst_ops = {
109 .family = AF_INET6,
110 .protocol = __constant_htons(ETH_P_IPV6),
111 .gc = ip6_dst_gc,
112 .gc_thresh = 1024,
113 .check = ip6_dst_check,
114 .destroy = ip6_dst_destroy,
115 .ifdown = ip6_dst_ifdown,
116 .negative_advice = ip6_negative_advice,
117 .link_failure = ip6_link_failure,
118 .update_pmtu = ip6_rt_update_pmtu,
119 .entry_size = sizeof(struct rt6_info),
122 struct rt6_info ip6_null_entry = {
123 .u = {
124 .dst = {
125 .__refcnt = ATOMIC_INIT(1),
126 .__use = 1,
127 .dev = &loopback_dev,
128 .obsolete = -1,
129 .error = -ENETUNREACH,
130 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
131 .input = ip6_pkt_discard,
132 .output = ip6_pkt_discard_out,
133 .ops = &ip6_dst_ops,
134 .path = (struct dst_entry*)&ip6_null_entry,
137 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
138 .rt6i_metric = ~(u32) 0,
139 .rt6i_ref = ATOMIC_INIT(1),
142 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
144 static int ip6_pkt_prohibit(struct sk_buff *skb);
145 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
146 static int ip6_pkt_blk_hole(struct sk_buff *skb);
148 struct rt6_info ip6_prohibit_entry = {
149 .u = {
150 .dst = {
151 .__refcnt = ATOMIC_INIT(1),
152 .__use = 1,
153 .dev = &loopback_dev,
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 .dev = &loopback_dev,
174 .obsolete = -1,
175 .error = -EINVAL,
176 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
177 .input = ip6_pkt_blk_hole,
178 .output = ip6_pkt_blk_hole,
179 .ops = &ip6_dst_ops,
180 .path = (struct dst_entry*)&ip6_blk_hole_entry,
183 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
184 .rt6i_metric = ~(u32) 0,
185 .rt6i_ref = ATOMIC_INIT(1),
188 #endif
190 /* allocate dst with ip6_dst_ops */
191 static __inline__ struct rt6_info *ip6_dst_alloc(void)
193 return (struct rt6_info *)dst_alloc(&ip6_dst_ops);
196 static void ip6_dst_destroy(struct dst_entry *dst)
198 struct rt6_info *rt = (struct rt6_info *)dst;
199 struct inet6_dev *idev = rt->rt6i_idev;
201 if (idev != NULL) {
202 rt->rt6i_idev = NULL;
203 in6_dev_put(idev);
207 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
208 int how)
210 struct rt6_info *rt = (struct rt6_info *)dst;
211 struct inet6_dev *idev = rt->rt6i_idev;
213 if (dev != &loopback_dev && idev != NULL && idev->dev == dev) {
214 struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev);
215 if (loopback_idev != NULL) {
216 rt->rt6i_idev = loopback_idev;
217 in6_dev_put(idev);
222 static __inline__ int rt6_check_expired(const struct rt6_info *rt)
224 return (rt->rt6i_flags & RTF_EXPIRES &&
225 time_after(jiffies, rt->rt6i_expires));
228 static inline int rt6_need_strict(struct in6_addr *daddr)
230 return (ipv6_addr_type(daddr) &
231 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
235 * Route lookup. Any table->tb6_lock is implied.
238 static __inline__ struct rt6_info *rt6_device_match(struct rt6_info *rt,
239 int oif,
240 int strict)
242 struct rt6_info *local = NULL;
243 struct rt6_info *sprt;
245 if (oif) {
246 for (sprt = rt; sprt; sprt = sprt->u.next) {
247 struct net_device *dev = sprt->rt6i_dev;
248 if (dev->ifindex == oif)
249 return sprt;
250 if (dev->flags & IFF_LOOPBACK) {
251 if (sprt->rt6i_idev == NULL ||
252 sprt->rt6i_idev->dev->ifindex != oif) {
253 if (strict && oif)
254 continue;
255 if (local && (!oif ||
256 local->rt6i_idev->dev->ifindex == oif))
257 continue;
259 local = sprt;
263 if (local)
264 return local;
266 if (strict)
267 return &ip6_null_entry;
269 return rt;
272 #ifdef CONFIG_IPV6_ROUTER_PREF
273 static void rt6_probe(struct rt6_info *rt)
275 struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
277 * Okay, this does not seem to be appropriate
278 * for now, however, we need to check if it
279 * is really so; aka Router Reachability Probing.
281 * Router Reachability Probe MUST be rate-limited
282 * to no more than one per minute.
284 if (!neigh || (neigh->nud_state & NUD_VALID))
285 return;
286 read_lock_bh(&neigh->lock);
287 if (!(neigh->nud_state & NUD_VALID) &&
288 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
289 struct in6_addr mcaddr;
290 struct in6_addr *target;
292 neigh->updated = jiffies;
293 read_unlock_bh(&neigh->lock);
295 target = (struct in6_addr *)&neigh->primary_key;
296 addrconf_addr_solict_mult(target, &mcaddr);
297 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
298 } else
299 read_unlock_bh(&neigh->lock);
301 #else
302 static inline void rt6_probe(struct rt6_info *rt)
304 return;
306 #endif
309 * Default Router Selection (RFC 2461 6.3.6)
311 static int inline rt6_check_dev(struct rt6_info *rt, int oif)
313 struct net_device *dev = rt->rt6i_dev;
314 if (!oif || dev->ifindex == oif)
315 return 2;
316 if ((dev->flags & IFF_LOOPBACK) &&
317 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
318 return 1;
319 return 0;
322 static int inline rt6_check_neigh(struct rt6_info *rt)
324 struct neighbour *neigh = rt->rt6i_nexthop;
325 int m = 0;
326 if (rt->rt6i_flags & RTF_NONEXTHOP ||
327 !(rt->rt6i_flags & RTF_GATEWAY))
328 m = 1;
329 else if (neigh) {
330 read_lock_bh(&neigh->lock);
331 if (neigh->nud_state & NUD_VALID)
332 m = 2;
333 else if (!(neigh->nud_state & NUD_FAILED))
334 m = 1;
335 read_unlock_bh(&neigh->lock);
337 return m;
340 static int rt6_score_route(struct rt6_info *rt, int oif,
341 int strict)
343 int m, n;
345 m = rt6_check_dev(rt, oif);
346 if (!m && (strict & RT6_LOOKUP_F_IFACE))
347 return -1;
348 #ifdef CONFIG_IPV6_ROUTER_PREF
349 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
350 #endif
351 n = rt6_check_neigh(rt);
352 if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
353 return -1;
354 return m;
357 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
358 int *mpri, struct rt6_info *match)
360 int m;
362 if (rt6_check_expired(rt))
363 goto out;
365 m = rt6_score_route(rt, oif, strict);
366 if (m < 0)
367 goto out;
369 if (m > *mpri) {
370 if (strict & RT6_LOOKUP_F_REACHABLE)
371 rt6_probe(match);
372 *mpri = m;
373 match = rt;
374 } else if (strict & RT6_LOOKUP_F_REACHABLE) {
375 rt6_probe(rt);
378 out:
379 return match;
382 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
383 struct rt6_info *rr_head,
384 u32 metric, int oif, int strict)
386 struct rt6_info *rt, *match;
387 int mpri = -1;
389 match = NULL;
390 for (rt = rr_head; rt && rt->rt6i_metric == metric;
391 rt = rt->u.next)
392 match = find_match(rt, oif, strict, &mpri, match);
393 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
394 rt = rt->u.next)
395 match = find_match(rt, oif, strict, &mpri, match);
397 return match;
400 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
402 struct rt6_info *match, *rt0;
404 RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
405 __FUNCTION__, fn->leaf, oif);
407 rt0 = fn->rr_ptr;
408 if (!rt0)
409 fn->rr_ptr = rt0 = fn->leaf;
411 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
413 if (!match &&
414 (strict & RT6_LOOKUP_F_REACHABLE)) {
415 struct rt6_info *next = rt0->u.next;
417 /* no entries matched; do round-robin */
418 if (!next || next->rt6i_metric != rt0->rt6i_metric)
419 next = fn->leaf;
421 if (next != rt0)
422 fn->rr_ptr = next;
425 RT6_TRACE("%s() => %p\n",
426 __FUNCTION__, match);
428 return (match ? match : &ip6_null_entry);
431 #ifdef CONFIG_IPV6_ROUTE_INFO
432 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
433 struct in6_addr *gwaddr)
435 struct route_info *rinfo = (struct route_info *) opt;
436 struct in6_addr prefix_buf, *prefix;
437 unsigned int pref;
438 u32 lifetime;
439 struct rt6_info *rt;
441 if (len < sizeof(struct route_info)) {
442 return -EINVAL;
445 /* Sanity check for prefix_len and length */
446 if (rinfo->length > 3) {
447 return -EINVAL;
448 } else if (rinfo->prefix_len > 128) {
449 return -EINVAL;
450 } else if (rinfo->prefix_len > 64) {
451 if (rinfo->length < 2) {
452 return -EINVAL;
454 } else if (rinfo->prefix_len > 0) {
455 if (rinfo->length < 1) {
456 return -EINVAL;
460 pref = rinfo->route_pref;
461 if (pref == ICMPV6_ROUTER_PREF_INVALID)
462 pref = ICMPV6_ROUTER_PREF_MEDIUM;
464 lifetime = ntohl(rinfo->lifetime);
465 if (lifetime == 0xffffffff) {
466 /* infinity */
467 } else if (lifetime > 0x7fffffff/HZ) {
468 /* Avoid arithmetic overflow */
469 lifetime = 0x7fffffff/HZ - 1;
472 if (rinfo->length == 3)
473 prefix = (struct in6_addr *)rinfo->prefix;
474 else {
475 /* this function is safe */
476 ipv6_addr_prefix(&prefix_buf,
477 (struct in6_addr *)rinfo->prefix,
478 rinfo->prefix_len);
479 prefix = &prefix_buf;
482 rt = rt6_get_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex);
484 if (rt && !lifetime) {
485 ip6_del_rt(rt);
486 rt = NULL;
489 if (!rt && lifetime)
490 rt = rt6_add_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
491 pref);
492 else if (rt)
493 rt->rt6i_flags = RTF_ROUTEINFO |
494 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
496 if (rt) {
497 if (lifetime == 0xffffffff) {
498 rt->rt6i_flags &= ~RTF_EXPIRES;
499 } else {
500 rt->rt6i_expires = jiffies + HZ * lifetime;
501 rt->rt6i_flags |= RTF_EXPIRES;
503 dst_release(&rt->u.dst);
505 return 0;
507 #endif
509 #define BACKTRACK(saddr) \
510 do { \
511 if (rt == &ip6_null_entry) { \
512 struct fib6_node *pn; \
513 while (1) { \
514 if (fn->fn_flags & RTN_TL_ROOT) \
515 goto out; \
516 pn = fn->parent; \
517 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
518 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
519 else \
520 fn = pn; \
521 if (fn->fn_flags & RTN_RTINFO) \
522 goto restart; \
525 } while(0)
527 static struct rt6_info *ip6_pol_route_lookup(struct fib6_table *table,
528 struct flowi *fl, int flags)
530 struct fib6_node *fn;
531 struct rt6_info *rt;
533 read_lock_bh(&table->tb6_lock);
534 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
535 restart:
536 rt = fn->leaf;
537 rt = rt6_device_match(rt, fl->oif, flags);
538 BACKTRACK(&fl->fl6_src);
539 out:
540 dst_hold(&rt->u.dst);
541 read_unlock_bh(&table->tb6_lock);
543 rt->u.dst.lastuse = jiffies;
544 rt->u.dst.__use++;
546 return rt;
550 struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr,
551 int oif, int strict)
553 struct flowi fl = {
554 .oif = oif,
555 .nl_u = {
556 .ip6_u = {
557 .daddr = *daddr,
561 struct dst_entry *dst;
562 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
564 if (saddr) {
565 memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
566 flags |= RT6_LOOKUP_F_HAS_SADDR;
569 dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_lookup);
570 if (dst->error == 0)
571 return (struct rt6_info *) dst;
573 dst_release(dst);
575 return NULL;
578 /* ip6_ins_rt is called with FREE table->tb6_lock.
579 It takes new route entry, the addition fails by any reason the
580 route is freed. In any case, if caller does not hold it, it may
581 be destroyed.
584 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
586 int err;
587 struct fib6_table *table;
589 table = rt->rt6i_table;
590 write_lock_bh(&table->tb6_lock);
591 err = fib6_add(&table->tb6_root, rt, info);
592 write_unlock_bh(&table->tb6_lock);
594 return err;
597 int ip6_ins_rt(struct rt6_info *rt)
599 return __ip6_ins_rt(rt, NULL);
602 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
603 struct in6_addr *saddr)
605 struct rt6_info *rt;
608 * Clone the route.
611 rt = ip6_rt_copy(ort);
613 if (rt) {
614 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
615 if (rt->rt6i_dst.plen != 128 &&
616 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
617 rt->rt6i_flags |= RTF_ANYCAST;
618 ipv6_addr_copy(&rt->rt6i_gateway, daddr);
621 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
622 rt->rt6i_dst.plen = 128;
623 rt->rt6i_flags |= RTF_CACHE;
624 rt->u.dst.flags |= DST_HOST;
626 #ifdef CONFIG_IPV6_SUBTREES
627 if (rt->rt6i_src.plen && saddr) {
628 ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
629 rt->rt6i_src.plen = 128;
631 #endif
633 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
637 return rt;
640 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
642 struct rt6_info *rt = ip6_rt_copy(ort);
643 if (rt) {
644 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
645 rt->rt6i_dst.plen = 128;
646 rt->rt6i_flags |= RTF_CACHE;
647 rt->u.dst.flags |= DST_HOST;
648 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
650 return rt;
653 static struct rt6_info *ip6_pol_route_input(struct fib6_table *table,
654 struct flowi *fl, int flags)
656 struct fib6_node *fn;
657 struct rt6_info *rt, *nrt;
658 int strict = 0;
659 int attempts = 3;
660 int err;
661 int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
663 strict |= flags & RT6_LOOKUP_F_IFACE;
665 relookup:
666 read_lock_bh(&table->tb6_lock);
668 restart_2:
669 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
671 restart:
672 rt = rt6_select(fn, fl->iif, strict | reachable);
673 BACKTRACK(&fl->fl6_src);
674 if (rt == &ip6_null_entry ||
675 rt->rt6i_flags & RTF_CACHE)
676 goto out;
678 dst_hold(&rt->u.dst);
679 read_unlock_bh(&table->tb6_lock);
681 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
682 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
683 else {
684 #if CLONE_OFFLINK_ROUTE
685 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
686 #else
687 goto out2;
688 #endif
691 dst_release(&rt->u.dst);
692 rt = nrt ? : &ip6_null_entry;
694 dst_hold(&rt->u.dst);
695 if (nrt) {
696 err = ip6_ins_rt(nrt);
697 if (!err)
698 goto out2;
701 if (--attempts <= 0)
702 goto out2;
705 * Race condition! In the gap, when table->tb6_lock was
706 * released someone could insert this route. Relookup.
708 dst_release(&rt->u.dst);
709 goto relookup;
711 out:
712 if (reachable) {
713 reachable = 0;
714 goto restart_2;
716 dst_hold(&rt->u.dst);
717 read_unlock_bh(&table->tb6_lock);
718 out2:
719 rt->u.dst.lastuse = jiffies;
720 rt->u.dst.__use++;
722 return rt;
725 void ip6_route_input(struct sk_buff *skb)
727 struct ipv6hdr *iph = skb->nh.ipv6h;
728 int flags = RT6_LOOKUP_F_HAS_SADDR;
729 struct flowi fl = {
730 .iif = skb->dev->ifindex,
731 .nl_u = {
732 .ip6_u = {
733 .daddr = iph->daddr,
734 .saddr = iph->saddr,
735 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
738 .mark = skb->mark,
739 .proto = iph->nexthdr,
742 if (rt6_need_strict(&iph->daddr))
743 flags |= RT6_LOOKUP_F_IFACE;
745 skb->dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_input);
748 static struct rt6_info *ip6_pol_route_output(struct fib6_table *table,
749 struct flowi *fl, int flags)
751 struct fib6_node *fn;
752 struct rt6_info *rt, *nrt;
753 int strict = 0;
754 int attempts = 3;
755 int err;
756 int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
758 strict |= flags & RT6_LOOKUP_F_IFACE;
760 relookup:
761 read_lock_bh(&table->tb6_lock);
763 restart_2:
764 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
766 restart:
767 rt = rt6_select(fn, fl->oif, strict | reachable);
768 BACKTRACK(&fl->fl6_src);
769 if (rt == &ip6_null_entry ||
770 rt->rt6i_flags & RTF_CACHE)
771 goto out;
773 dst_hold(&rt->u.dst);
774 read_unlock_bh(&table->tb6_lock);
776 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
777 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
778 else {
779 #if CLONE_OFFLINK_ROUTE
780 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
781 #else
782 goto out2;
783 #endif
786 dst_release(&rt->u.dst);
787 rt = nrt ? : &ip6_null_entry;
789 dst_hold(&rt->u.dst);
790 if (nrt) {
791 err = ip6_ins_rt(nrt);
792 if (!err)
793 goto out2;
796 if (--attempts <= 0)
797 goto out2;
800 * Race condition! In the gap, when table->tb6_lock was
801 * released someone could insert this route. Relookup.
803 dst_release(&rt->u.dst);
804 goto relookup;
806 out:
807 if (reachable) {
808 reachable = 0;
809 goto restart_2;
811 dst_hold(&rt->u.dst);
812 read_unlock_bh(&table->tb6_lock);
813 out2:
814 rt->u.dst.lastuse = jiffies;
815 rt->u.dst.__use++;
816 return rt;
819 struct dst_entry * ip6_route_output(struct sock *sk, struct flowi *fl)
821 int flags = 0;
823 if (rt6_need_strict(&fl->fl6_dst))
824 flags |= RT6_LOOKUP_F_IFACE;
826 if (!ipv6_addr_any(&fl->fl6_src))
827 flags |= RT6_LOOKUP_F_HAS_SADDR;
829 return fib6_rule_lookup(fl, flags, ip6_pol_route_output);
834 * Destination cache support functions
837 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
839 struct rt6_info *rt;
841 rt = (struct rt6_info *) dst;
843 if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
844 return dst;
846 return NULL;
849 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
851 struct rt6_info *rt = (struct rt6_info *) dst;
853 if (rt) {
854 if (rt->rt6i_flags & RTF_CACHE)
855 ip6_del_rt(rt);
856 else
857 dst_release(dst);
859 return NULL;
862 static void ip6_link_failure(struct sk_buff *skb)
864 struct rt6_info *rt;
866 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev);
868 rt = (struct rt6_info *) skb->dst;
869 if (rt) {
870 if (rt->rt6i_flags&RTF_CACHE) {
871 dst_set_expires(&rt->u.dst, 0);
872 rt->rt6i_flags |= RTF_EXPIRES;
873 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
874 rt->rt6i_node->fn_sernum = -1;
878 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
880 struct rt6_info *rt6 = (struct rt6_info*)dst;
882 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
883 rt6->rt6i_flags |= RTF_MODIFIED;
884 if (mtu < IPV6_MIN_MTU) {
885 mtu = IPV6_MIN_MTU;
886 dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
888 dst->metrics[RTAX_MTU-1] = mtu;
889 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
893 static int ipv6_get_mtu(struct net_device *dev);
895 static inline unsigned int ipv6_advmss(unsigned int mtu)
897 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
899 if (mtu < ip6_rt_min_advmss)
900 mtu = ip6_rt_min_advmss;
903 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
904 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
905 * IPV6_MAXPLEN is also valid and means: "any MSS,
906 * rely only on pmtu discovery"
908 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
909 mtu = IPV6_MAXPLEN;
910 return mtu;
913 static struct dst_entry *ndisc_dst_gc_list;
914 static DEFINE_SPINLOCK(ndisc_lock);
916 struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
917 struct neighbour *neigh,
918 struct in6_addr *addr,
919 int (*output)(struct sk_buff *))
921 struct rt6_info *rt;
922 struct inet6_dev *idev = in6_dev_get(dev);
924 if (unlikely(idev == NULL))
925 return NULL;
927 rt = ip6_dst_alloc();
928 if (unlikely(rt == NULL)) {
929 in6_dev_put(idev);
930 goto out;
933 dev_hold(dev);
934 if (neigh)
935 neigh_hold(neigh);
936 else
937 neigh = ndisc_get_neigh(dev, addr);
939 rt->rt6i_dev = dev;
940 rt->rt6i_idev = idev;
941 rt->rt6i_nexthop = neigh;
942 atomic_set(&rt->u.dst.__refcnt, 1);
943 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
944 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
945 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
946 rt->u.dst.output = output;
948 #if 0 /* there's no chance to use these for ndisc */
949 rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
950 ? DST_HOST
951 : 0;
952 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
953 rt->rt6i_dst.plen = 128;
954 #endif
956 spin_lock_bh(&ndisc_lock);
957 rt->u.dst.next = ndisc_dst_gc_list;
958 ndisc_dst_gc_list = &rt->u.dst;
959 spin_unlock_bh(&ndisc_lock);
961 fib6_force_start_gc();
963 out:
964 return &rt->u.dst;
967 int ndisc_dst_gc(int *more)
969 struct dst_entry *dst, *next, **pprev;
970 int freed;
972 next = NULL;
973 freed = 0;
975 spin_lock_bh(&ndisc_lock);
976 pprev = &ndisc_dst_gc_list;
978 while ((dst = *pprev) != NULL) {
979 if (!atomic_read(&dst->__refcnt)) {
980 *pprev = dst->next;
981 dst_free(dst);
982 freed++;
983 } else {
984 pprev = &dst->next;
985 (*more)++;
989 spin_unlock_bh(&ndisc_lock);
991 return freed;
994 static int ip6_dst_gc(void)
996 static unsigned expire = 30*HZ;
997 static unsigned long last_gc;
998 unsigned long now = jiffies;
1000 if (time_after(last_gc + ip6_rt_gc_min_interval, now) &&
1001 atomic_read(&ip6_dst_ops.entries) <= ip6_rt_max_size)
1002 goto out;
1004 expire++;
1005 fib6_run_gc(expire);
1006 last_gc = now;
1007 if (atomic_read(&ip6_dst_ops.entries) < ip6_dst_ops.gc_thresh)
1008 expire = ip6_rt_gc_timeout>>1;
1010 out:
1011 expire -= expire>>ip6_rt_gc_elasticity;
1012 return (atomic_read(&ip6_dst_ops.entries) > ip6_rt_max_size);
1015 /* Clean host part of a prefix. Not necessary in radix tree,
1016 but results in cleaner routing tables.
1018 Remove it only when all the things will work!
1021 static int ipv6_get_mtu(struct net_device *dev)
1023 int mtu = IPV6_MIN_MTU;
1024 struct inet6_dev *idev;
1026 idev = in6_dev_get(dev);
1027 if (idev) {
1028 mtu = idev->cnf.mtu6;
1029 in6_dev_put(idev);
1031 return mtu;
1034 int ipv6_get_hoplimit(struct net_device *dev)
1036 int hoplimit = ipv6_devconf.hop_limit;
1037 struct inet6_dev *idev;
1039 idev = in6_dev_get(dev);
1040 if (idev) {
1041 hoplimit = idev->cnf.hop_limit;
1042 in6_dev_put(idev);
1044 return hoplimit;
1051 int ip6_route_add(struct fib6_config *cfg)
1053 int err;
1054 struct rt6_info *rt = NULL;
1055 struct net_device *dev = NULL;
1056 struct inet6_dev *idev = NULL;
1057 struct fib6_table *table;
1058 int addr_type;
1060 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1061 return -EINVAL;
1062 #ifndef CONFIG_IPV6_SUBTREES
1063 if (cfg->fc_src_len)
1064 return -EINVAL;
1065 #endif
1066 if (cfg->fc_ifindex) {
1067 err = -ENODEV;
1068 dev = dev_get_by_index(cfg->fc_ifindex);
1069 if (!dev)
1070 goto out;
1071 idev = in6_dev_get(dev);
1072 if (!idev)
1073 goto out;
1076 if (cfg->fc_metric == 0)
1077 cfg->fc_metric = IP6_RT_PRIO_USER;
1079 table = fib6_new_table(cfg->fc_table);
1080 if (table == NULL) {
1081 err = -ENOBUFS;
1082 goto out;
1085 rt = ip6_dst_alloc();
1087 if (rt == NULL) {
1088 err = -ENOMEM;
1089 goto out;
1092 rt->u.dst.obsolete = -1;
1093 rt->rt6i_expires = jiffies + clock_t_to_jiffies(cfg->fc_expires);
1095 if (cfg->fc_protocol == RTPROT_UNSPEC)
1096 cfg->fc_protocol = RTPROT_BOOT;
1097 rt->rt6i_protocol = cfg->fc_protocol;
1099 addr_type = ipv6_addr_type(&cfg->fc_dst);
1101 if (addr_type & IPV6_ADDR_MULTICAST)
1102 rt->u.dst.input = ip6_mc_input;
1103 else
1104 rt->u.dst.input = ip6_forward;
1106 rt->u.dst.output = ip6_output;
1108 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1109 rt->rt6i_dst.plen = cfg->fc_dst_len;
1110 if (rt->rt6i_dst.plen == 128)
1111 rt->u.dst.flags = DST_HOST;
1113 #ifdef CONFIG_IPV6_SUBTREES
1114 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1115 rt->rt6i_src.plen = cfg->fc_src_len;
1116 #endif
1118 rt->rt6i_metric = cfg->fc_metric;
1120 /* We cannot add true routes via loopback here,
1121 they would result in kernel looping; promote them to reject routes
1123 if ((cfg->fc_flags & RTF_REJECT) ||
1124 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
1125 /* hold loopback dev/idev if we haven't done so. */
1126 if (dev != &loopback_dev) {
1127 if (dev) {
1128 dev_put(dev);
1129 in6_dev_put(idev);
1131 dev = &loopback_dev;
1132 dev_hold(dev);
1133 idev = in6_dev_get(dev);
1134 if (!idev) {
1135 err = -ENODEV;
1136 goto out;
1139 rt->u.dst.output = ip6_pkt_discard_out;
1140 rt->u.dst.input = ip6_pkt_discard;
1141 rt->u.dst.error = -ENETUNREACH;
1142 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1143 goto install_route;
1146 if (cfg->fc_flags & RTF_GATEWAY) {
1147 struct in6_addr *gw_addr;
1148 int gwa_type;
1150 gw_addr = &cfg->fc_gateway;
1151 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1152 gwa_type = ipv6_addr_type(gw_addr);
1154 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1155 struct rt6_info *grt;
1157 /* IPv6 strictly inhibits using not link-local
1158 addresses as nexthop address.
1159 Otherwise, router will not able to send redirects.
1160 It is very good, but in some (rare!) circumstances
1161 (SIT, PtP, NBMA NOARP links) it is handy to allow
1162 some exceptions. --ANK
1164 err = -EINVAL;
1165 if (!(gwa_type&IPV6_ADDR_UNICAST))
1166 goto out;
1168 grt = rt6_lookup(gw_addr, NULL, cfg->fc_ifindex, 1);
1170 err = -EHOSTUNREACH;
1171 if (grt == NULL)
1172 goto out;
1173 if (dev) {
1174 if (dev != grt->rt6i_dev) {
1175 dst_release(&grt->u.dst);
1176 goto out;
1178 } else {
1179 dev = grt->rt6i_dev;
1180 idev = grt->rt6i_idev;
1181 dev_hold(dev);
1182 in6_dev_hold(grt->rt6i_idev);
1184 if (!(grt->rt6i_flags&RTF_GATEWAY))
1185 err = 0;
1186 dst_release(&grt->u.dst);
1188 if (err)
1189 goto out;
1191 err = -EINVAL;
1192 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1193 goto out;
1196 err = -ENODEV;
1197 if (dev == NULL)
1198 goto out;
1200 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1201 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1202 if (IS_ERR(rt->rt6i_nexthop)) {
1203 err = PTR_ERR(rt->rt6i_nexthop);
1204 rt->rt6i_nexthop = NULL;
1205 goto out;
1209 rt->rt6i_flags = cfg->fc_flags;
1211 install_route:
1212 if (cfg->fc_mx) {
1213 struct nlattr *nla;
1214 int remaining;
1216 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1217 int type = nla->nla_type;
1219 if (type) {
1220 if (type > RTAX_MAX) {
1221 err = -EINVAL;
1222 goto out;
1225 rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
1230 if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0)
1231 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1232 if (!rt->u.dst.metrics[RTAX_MTU-1])
1233 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
1234 if (!rt->u.dst.metrics[RTAX_ADVMSS-1])
1235 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1236 rt->u.dst.dev = dev;
1237 rt->rt6i_idev = idev;
1238 rt->rt6i_table = table;
1239 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1241 out:
1242 if (dev)
1243 dev_put(dev);
1244 if (idev)
1245 in6_dev_put(idev);
1246 if (rt)
1247 dst_free(&rt->u.dst);
1248 return err;
1251 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1253 int err;
1254 struct fib6_table *table;
1256 if (rt == &ip6_null_entry)
1257 return -ENOENT;
1259 table = rt->rt6i_table;
1260 write_lock_bh(&table->tb6_lock);
1262 err = fib6_del(rt, info);
1263 dst_release(&rt->u.dst);
1265 write_unlock_bh(&table->tb6_lock);
1267 return err;
1270 int ip6_del_rt(struct rt6_info *rt)
1272 return __ip6_del_rt(rt, NULL);
1275 static int ip6_route_del(struct fib6_config *cfg)
1277 struct fib6_table *table;
1278 struct fib6_node *fn;
1279 struct rt6_info *rt;
1280 int err = -ESRCH;
1282 table = fib6_get_table(cfg->fc_table);
1283 if (table == NULL)
1284 return err;
1286 read_lock_bh(&table->tb6_lock);
1288 fn = fib6_locate(&table->tb6_root,
1289 &cfg->fc_dst, cfg->fc_dst_len,
1290 &cfg->fc_src, cfg->fc_src_len);
1292 if (fn) {
1293 for (rt = fn->leaf; rt; rt = rt->u.next) {
1294 if (cfg->fc_ifindex &&
1295 (rt->rt6i_dev == NULL ||
1296 rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1297 continue;
1298 if (cfg->fc_flags & RTF_GATEWAY &&
1299 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1300 continue;
1301 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1302 continue;
1303 dst_hold(&rt->u.dst);
1304 read_unlock_bh(&table->tb6_lock);
1306 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1309 read_unlock_bh(&table->tb6_lock);
1311 return err;
1315 * Handle redirects
1317 struct ip6rd_flowi {
1318 struct flowi fl;
1319 struct in6_addr gateway;
1322 static struct rt6_info *__ip6_route_redirect(struct fib6_table *table,
1323 struct flowi *fl,
1324 int flags)
1326 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
1327 struct rt6_info *rt;
1328 struct fib6_node *fn;
1331 * Get the "current" route for this destination and
1332 * check if the redirect has come from approriate router.
1334 * RFC 2461 specifies that redirects should only be
1335 * accepted if they come from the nexthop to the target.
1336 * Due to the way the routes are chosen, this notion
1337 * is a bit fuzzy and one might need to check all possible
1338 * routes.
1341 read_lock_bh(&table->tb6_lock);
1342 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1343 restart:
1344 for (rt = fn->leaf; rt; rt = rt->u.next) {
1346 * Current route is on-link; redirect is always invalid.
1348 * Seems, previous statement is not true. It could
1349 * be node, which looks for us as on-link (f.e. proxy ndisc)
1350 * But then router serving it might decide, that we should
1351 * know truth 8)8) --ANK (980726).
1353 if (rt6_check_expired(rt))
1354 continue;
1355 if (!(rt->rt6i_flags & RTF_GATEWAY))
1356 continue;
1357 if (fl->oif != rt->rt6i_dev->ifindex)
1358 continue;
1359 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1360 continue;
1361 break;
1364 if (!rt)
1365 rt = &ip6_null_entry;
1366 BACKTRACK(&fl->fl6_src);
1367 out:
1368 dst_hold(&rt->u.dst);
1370 read_unlock_bh(&table->tb6_lock);
1372 return rt;
1375 static struct rt6_info *ip6_route_redirect(struct in6_addr *dest,
1376 struct in6_addr *src,
1377 struct in6_addr *gateway,
1378 struct net_device *dev)
1380 int flags = RT6_LOOKUP_F_HAS_SADDR;
1381 struct ip6rd_flowi rdfl = {
1382 .fl = {
1383 .oif = dev->ifindex,
1384 .nl_u = {
1385 .ip6_u = {
1386 .daddr = *dest,
1387 .saddr = *src,
1391 .gateway = *gateway,
1394 if (rt6_need_strict(dest))
1395 flags |= RT6_LOOKUP_F_IFACE;
1397 return (struct rt6_info *)fib6_rule_lookup((struct flowi *)&rdfl, flags, __ip6_route_redirect);
1400 void rt6_redirect(struct in6_addr *dest, struct in6_addr *src,
1401 struct in6_addr *saddr,
1402 struct neighbour *neigh, u8 *lladdr, int on_link)
1404 struct rt6_info *rt, *nrt = NULL;
1405 struct netevent_redirect netevent;
1407 rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1409 if (rt == &ip6_null_entry) {
1410 if (net_ratelimit())
1411 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1412 "for redirect target\n");
1413 goto out;
1417 * We have finally decided to accept it.
1420 neigh_update(neigh, lladdr, NUD_STALE,
1421 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1422 NEIGH_UPDATE_F_OVERRIDE|
1423 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1424 NEIGH_UPDATE_F_ISROUTER))
1428 * Redirect received -> path was valid.
1429 * Look, redirects are sent only in response to data packets,
1430 * so that this nexthop apparently is reachable. --ANK
1432 dst_confirm(&rt->u.dst);
1434 /* Duplicate redirect: silently ignore. */
1435 if (neigh == rt->u.dst.neighbour)
1436 goto out;
1438 nrt = ip6_rt_copy(rt);
1439 if (nrt == NULL)
1440 goto out;
1442 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1443 if (on_link)
1444 nrt->rt6i_flags &= ~RTF_GATEWAY;
1446 ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1447 nrt->rt6i_dst.plen = 128;
1448 nrt->u.dst.flags |= DST_HOST;
1450 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1451 nrt->rt6i_nexthop = neigh_clone(neigh);
1452 /* Reset pmtu, it may be better */
1453 nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
1454 nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&nrt->u.dst));
1456 if (ip6_ins_rt(nrt))
1457 goto out;
1459 netevent.old = &rt->u.dst;
1460 netevent.new = &nrt->u.dst;
1461 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1463 if (rt->rt6i_flags&RTF_CACHE) {
1464 ip6_del_rt(rt);
1465 return;
1468 out:
1469 dst_release(&rt->u.dst);
1470 return;
1474 * Handle ICMP "packet too big" messages
1475 * i.e. Path MTU discovery
1478 void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
1479 struct net_device *dev, u32 pmtu)
1481 struct rt6_info *rt, *nrt;
1482 int allfrag = 0;
1484 rt = rt6_lookup(daddr, saddr, dev->ifindex, 0);
1485 if (rt == NULL)
1486 return;
1488 if (pmtu >= dst_mtu(&rt->u.dst))
1489 goto out;
1491 if (pmtu < IPV6_MIN_MTU) {
1493 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1494 * MTU (1280) and a fragment header should always be included
1495 * after a node receiving Too Big message reporting PMTU is
1496 * less than the IPv6 Minimum Link MTU.
1498 pmtu = IPV6_MIN_MTU;
1499 allfrag = 1;
1502 /* New mtu received -> path was valid.
1503 They are sent only in response to data packets,
1504 so that this nexthop apparently is reachable. --ANK
1506 dst_confirm(&rt->u.dst);
1508 /* Host route. If it is static, it would be better
1509 not to override it, but add new one, so that
1510 when cache entry will expire old pmtu
1511 would return automatically.
1513 if (rt->rt6i_flags & RTF_CACHE) {
1514 rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1515 if (allfrag)
1516 rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1517 dst_set_expires(&rt->u.dst, ip6_rt_mtu_expires);
1518 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1519 goto out;
1522 /* Network route.
1523 Two cases are possible:
1524 1. It is connected route. Action: COW
1525 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1527 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1528 nrt = rt6_alloc_cow(rt, daddr, saddr);
1529 else
1530 nrt = rt6_alloc_clone(rt, daddr);
1532 if (nrt) {
1533 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1534 if (allfrag)
1535 nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1537 /* According to RFC 1981, detecting PMTU increase shouldn't be
1538 * happened within 5 mins, the recommended timer is 10 mins.
1539 * Here this route expiration time is set to ip6_rt_mtu_expires
1540 * which is 10 mins. After 10 mins the decreased pmtu is expired
1541 * and detecting PMTU increase will be automatically happened.
1543 dst_set_expires(&nrt->u.dst, ip6_rt_mtu_expires);
1544 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1546 ip6_ins_rt(nrt);
1548 out:
1549 dst_release(&rt->u.dst);
1553 * Misc support functions
1556 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1558 struct rt6_info *rt = ip6_dst_alloc();
1560 if (rt) {
1561 rt->u.dst.input = ort->u.dst.input;
1562 rt->u.dst.output = ort->u.dst.output;
1564 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1565 rt->u.dst.error = ort->u.dst.error;
1566 rt->u.dst.dev = ort->u.dst.dev;
1567 if (rt->u.dst.dev)
1568 dev_hold(rt->u.dst.dev);
1569 rt->rt6i_idev = ort->rt6i_idev;
1570 if (rt->rt6i_idev)
1571 in6_dev_hold(rt->rt6i_idev);
1572 rt->u.dst.lastuse = jiffies;
1573 rt->rt6i_expires = 0;
1575 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1576 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1577 rt->rt6i_metric = 0;
1579 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1580 #ifdef CONFIG_IPV6_SUBTREES
1581 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1582 #endif
1583 rt->rt6i_table = ort->rt6i_table;
1585 return rt;
1588 #ifdef CONFIG_IPV6_ROUTE_INFO
1589 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
1590 struct in6_addr *gwaddr, int ifindex)
1592 struct fib6_node *fn;
1593 struct rt6_info *rt = NULL;
1594 struct fib6_table *table;
1596 table = fib6_get_table(RT6_TABLE_INFO);
1597 if (table == NULL)
1598 return NULL;
1600 write_lock_bh(&table->tb6_lock);
1601 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1602 if (!fn)
1603 goto out;
1605 for (rt = fn->leaf; rt; rt = rt->u.next) {
1606 if (rt->rt6i_dev->ifindex != ifindex)
1607 continue;
1608 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1609 continue;
1610 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1611 continue;
1612 dst_hold(&rt->u.dst);
1613 break;
1615 out:
1616 write_unlock_bh(&table->tb6_lock);
1617 return rt;
1620 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
1621 struct in6_addr *gwaddr, int ifindex,
1622 unsigned pref)
1624 struct fib6_config cfg = {
1625 .fc_table = RT6_TABLE_INFO,
1626 .fc_metric = 1024,
1627 .fc_ifindex = ifindex,
1628 .fc_dst_len = prefixlen,
1629 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1630 RTF_UP | RTF_PREF(pref),
1633 ipv6_addr_copy(&cfg.fc_dst, prefix);
1634 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1636 /* We should treat it as a default route if prefix length is 0. */
1637 if (!prefixlen)
1638 cfg.fc_flags |= RTF_DEFAULT;
1640 ip6_route_add(&cfg);
1642 return rt6_get_route_info(prefix, prefixlen, gwaddr, ifindex);
1644 #endif
1646 struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1648 struct rt6_info *rt;
1649 struct fib6_table *table;
1651 table = fib6_get_table(RT6_TABLE_DFLT);
1652 if (table == NULL)
1653 return NULL;
1655 write_lock_bh(&table->tb6_lock);
1656 for (rt = table->tb6_root.leaf; rt; rt=rt->u.next) {
1657 if (dev == rt->rt6i_dev &&
1658 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1659 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1660 break;
1662 if (rt)
1663 dst_hold(&rt->u.dst);
1664 write_unlock_bh(&table->tb6_lock);
1665 return rt;
1668 struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1669 struct net_device *dev,
1670 unsigned int pref)
1672 struct fib6_config cfg = {
1673 .fc_table = RT6_TABLE_DFLT,
1674 .fc_metric = 1024,
1675 .fc_ifindex = dev->ifindex,
1676 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1677 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1680 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1682 ip6_route_add(&cfg);
1684 return rt6_get_dflt_router(gwaddr, dev);
1687 void rt6_purge_dflt_routers(void)
1689 struct rt6_info *rt;
1690 struct fib6_table *table;
1692 /* NOTE: Keep consistent with rt6_get_dflt_router */
1693 table = fib6_get_table(RT6_TABLE_DFLT);
1694 if (table == NULL)
1695 return;
1697 restart:
1698 read_lock_bh(&table->tb6_lock);
1699 for (rt = table->tb6_root.leaf; rt; rt = rt->u.next) {
1700 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1701 dst_hold(&rt->u.dst);
1702 read_unlock_bh(&table->tb6_lock);
1703 ip6_del_rt(rt);
1704 goto restart;
1707 read_unlock_bh(&table->tb6_lock);
1710 static void rtmsg_to_fib6_config(struct in6_rtmsg *rtmsg,
1711 struct fib6_config *cfg)
1713 memset(cfg, 0, sizeof(*cfg));
1715 cfg->fc_table = RT6_TABLE_MAIN;
1716 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1717 cfg->fc_metric = rtmsg->rtmsg_metric;
1718 cfg->fc_expires = rtmsg->rtmsg_info;
1719 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1720 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1721 cfg->fc_flags = rtmsg->rtmsg_flags;
1723 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1724 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1725 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1728 int ipv6_route_ioctl(unsigned int cmd, void __user *arg)
1730 struct fib6_config cfg;
1731 struct in6_rtmsg rtmsg;
1732 int err;
1734 switch(cmd) {
1735 case SIOCADDRT: /* Add a route */
1736 case SIOCDELRT: /* Delete a route */
1737 if (!capable(CAP_NET_ADMIN))
1738 return -EPERM;
1739 err = copy_from_user(&rtmsg, arg,
1740 sizeof(struct in6_rtmsg));
1741 if (err)
1742 return -EFAULT;
1744 rtmsg_to_fib6_config(&rtmsg, &cfg);
1746 rtnl_lock();
1747 switch (cmd) {
1748 case SIOCADDRT:
1749 err = ip6_route_add(&cfg);
1750 break;
1751 case SIOCDELRT:
1752 err = ip6_route_del(&cfg);
1753 break;
1754 default:
1755 err = -EINVAL;
1757 rtnl_unlock();
1759 return err;
1762 return -EINVAL;
1766 * Drop the packet on the floor
1769 static inline int ip6_pkt_drop(struct sk_buff *skb, int code)
1771 int type = ipv6_addr_type(&skb->nh.ipv6h->daddr);
1772 if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED)
1773 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INADDRERRORS);
1775 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_OUTNOROUTES);
1776 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev);
1777 kfree_skb(skb);
1778 return 0;
1781 static int ip6_pkt_discard(struct sk_buff *skb)
1783 return ip6_pkt_drop(skb, ICMPV6_NOROUTE);
1786 static int ip6_pkt_discard_out(struct sk_buff *skb)
1788 skb->dev = skb->dst->dev;
1789 return ip6_pkt_discard(skb);
1792 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1794 static int ip6_pkt_prohibit(struct sk_buff *skb)
1796 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED);
1799 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
1801 skb->dev = skb->dst->dev;
1802 return ip6_pkt_prohibit(skb);
1805 static int ip6_pkt_blk_hole(struct sk_buff *skb)
1807 kfree_skb(skb);
1808 return 0;
1811 #endif
1814 * Allocate a dst for local (unicast / anycast) address.
1817 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
1818 const struct in6_addr *addr,
1819 int anycast)
1821 struct rt6_info *rt = ip6_dst_alloc();
1823 if (rt == NULL)
1824 return ERR_PTR(-ENOMEM);
1826 dev_hold(&loopback_dev);
1827 in6_dev_hold(idev);
1829 rt->u.dst.flags = DST_HOST;
1830 rt->u.dst.input = ip6_input;
1831 rt->u.dst.output = ip6_output;
1832 rt->rt6i_dev = &loopback_dev;
1833 rt->rt6i_idev = idev;
1834 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1835 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1836 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1837 rt->u.dst.obsolete = -1;
1839 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1840 if (anycast)
1841 rt->rt6i_flags |= RTF_ANYCAST;
1842 else
1843 rt->rt6i_flags |= RTF_LOCAL;
1844 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
1845 if (rt->rt6i_nexthop == NULL) {
1846 dst_free(&rt->u.dst);
1847 return ERR_PTR(-ENOMEM);
1850 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1851 rt->rt6i_dst.plen = 128;
1852 rt->rt6i_table = fib6_get_table(RT6_TABLE_LOCAL);
1854 atomic_set(&rt->u.dst.__refcnt, 1);
1856 return rt;
1859 static int fib6_ifdown(struct rt6_info *rt, void *arg)
1861 if (((void*)rt->rt6i_dev == arg || arg == NULL) &&
1862 rt != &ip6_null_entry) {
1863 RT6_TRACE("deleted by ifdown %p\n", rt);
1864 return -1;
1866 return 0;
1869 void rt6_ifdown(struct net_device *dev)
1871 fib6_clean_all(fib6_ifdown, 0, dev);
1874 struct rt6_mtu_change_arg
1876 struct net_device *dev;
1877 unsigned mtu;
1880 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
1882 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
1883 struct inet6_dev *idev;
1885 /* In IPv6 pmtu discovery is not optional,
1886 so that RTAX_MTU lock cannot disable it.
1887 We still use this lock to block changes
1888 caused by addrconf/ndisc.
1891 idev = __in6_dev_get(arg->dev);
1892 if (idev == NULL)
1893 return 0;
1895 /* For administrative MTU increase, there is no way to discover
1896 IPv6 PMTU increase, so PMTU increase should be updated here.
1897 Since RFC 1981 doesn't include administrative MTU increase
1898 update PMTU increase is a MUST. (i.e. jumbo frame)
1901 If new MTU is less than route PMTU, this new MTU will be the
1902 lowest MTU in the path, update the route PMTU to reflect PMTU
1903 decreases; if new MTU is greater than route PMTU, and the
1904 old MTU is the lowest MTU in the path, update the route PMTU
1905 to reflect the increase. In this case if the other nodes' MTU
1906 also have the lowest MTU, TOO BIG MESSAGE will be lead to
1907 PMTU discouvery.
1909 if (rt->rt6i_dev == arg->dev &&
1910 !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1911 (dst_mtu(&rt->u.dst) > arg->mtu ||
1912 (dst_mtu(&rt->u.dst) < arg->mtu &&
1913 dst_mtu(&rt->u.dst) == idev->cnf.mtu6)))
1914 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
1915 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 struct nla_policy rtm_ipv6_policy[RTA_MAX+1] __read_mostly = {
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 int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2008 struct fib6_config cfg;
2009 int err;
2011 err = rtm_to_fib6_config(skb, nlh, &cfg);
2012 if (err < 0)
2013 return err;
2015 return ip6_route_del(&cfg);
2018 int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2020 struct fib6_config cfg;
2021 int err;
2023 err = rtm_to_fib6_config(skb, nlh, &cfg);
2024 if (err < 0)
2025 return err;
2027 return ip6_route_add(&cfg);
2030 static inline size_t rt6_nlmsg_size(void)
2032 return NLMSG_ALIGN(sizeof(struct rtmsg))
2033 + nla_total_size(16) /* RTA_SRC */
2034 + nla_total_size(16) /* RTA_DST */
2035 + nla_total_size(16) /* RTA_GATEWAY */
2036 + nla_total_size(16) /* RTA_PREFSRC */
2037 + nla_total_size(4) /* RTA_TABLE */
2038 + nla_total_size(4) /* RTA_IIF */
2039 + nla_total_size(4) /* RTA_OIF */
2040 + nla_total_size(4) /* RTA_PRIORITY */
2041 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2042 + nla_total_size(sizeof(struct rta_cacheinfo));
2045 static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
2046 struct in6_addr *dst, struct in6_addr *src,
2047 int iif, int type, u32 pid, u32 seq,
2048 int prefix, unsigned int flags)
2050 struct rtmsg *rtm;
2051 struct nlmsghdr *nlh;
2052 long expires;
2053 u32 table;
2055 if (prefix) { /* user wants prefix routes only */
2056 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2057 /* success since this is not a prefix route */
2058 return 1;
2062 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2063 if (nlh == NULL)
2064 return -ENOBUFS;
2066 rtm = nlmsg_data(nlh);
2067 rtm->rtm_family = AF_INET6;
2068 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2069 rtm->rtm_src_len = rt->rt6i_src.plen;
2070 rtm->rtm_tos = 0;
2071 if (rt->rt6i_table)
2072 table = rt->rt6i_table->tb6_id;
2073 else
2074 table = RT6_TABLE_UNSPEC;
2075 rtm->rtm_table = table;
2076 NLA_PUT_U32(skb, RTA_TABLE, table);
2077 if (rt->rt6i_flags&RTF_REJECT)
2078 rtm->rtm_type = RTN_UNREACHABLE;
2079 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2080 rtm->rtm_type = RTN_LOCAL;
2081 else
2082 rtm->rtm_type = RTN_UNICAST;
2083 rtm->rtm_flags = 0;
2084 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2085 rtm->rtm_protocol = rt->rt6i_protocol;
2086 if (rt->rt6i_flags&RTF_DYNAMIC)
2087 rtm->rtm_protocol = RTPROT_REDIRECT;
2088 else if (rt->rt6i_flags & RTF_ADDRCONF)
2089 rtm->rtm_protocol = RTPROT_KERNEL;
2090 else if (rt->rt6i_flags&RTF_DEFAULT)
2091 rtm->rtm_protocol = RTPROT_RA;
2093 if (rt->rt6i_flags&RTF_CACHE)
2094 rtm->rtm_flags |= RTM_F_CLONED;
2096 if (dst) {
2097 NLA_PUT(skb, RTA_DST, 16, dst);
2098 rtm->rtm_dst_len = 128;
2099 } else if (rtm->rtm_dst_len)
2100 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2101 #ifdef CONFIG_IPV6_SUBTREES
2102 if (src) {
2103 NLA_PUT(skb, RTA_SRC, 16, src);
2104 rtm->rtm_src_len = 128;
2105 } else if (rtm->rtm_src_len)
2106 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2107 #endif
2108 if (iif)
2109 NLA_PUT_U32(skb, RTA_IIF, iif);
2110 else if (dst) {
2111 struct in6_addr saddr_buf;
2112 if (ipv6_get_saddr(&rt->u.dst, dst, &saddr_buf) == 0)
2113 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2116 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2117 goto nla_put_failure;
2119 if (rt->u.dst.neighbour)
2120 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);
2122 if (rt->u.dst.dev)
2123 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2125 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2127 expires = rt->rt6i_expires ? rt->rt6i_expires - jiffies : 0;
2128 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0,
2129 expires, rt->u.dst.error) < 0)
2130 goto nla_put_failure;
2132 return nlmsg_end(skb, nlh);
2134 nla_put_failure:
2135 return nlmsg_cancel(skb, nlh);
2138 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2140 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2141 int prefix;
2143 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2144 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2145 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2146 } else
2147 prefix = 0;
2149 return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2150 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2151 prefix, NLM_F_MULTI);
2154 int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2156 struct nlattr *tb[RTA_MAX+1];
2157 struct rt6_info *rt;
2158 struct sk_buff *skb;
2159 struct rtmsg *rtm;
2160 struct flowi fl;
2161 int err, iif = 0;
2163 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2164 if (err < 0)
2165 goto errout;
2167 err = -EINVAL;
2168 memset(&fl, 0, sizeof(fl));
2170 if (tb[RTA_SRC]) {
2171 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2172 goto errout;
2174 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
2177 if (tb[RTA_DST]) {
2178 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2179 goto errout;
2181 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
2184 if (tb[RTA_IIF])
2185 iif = nla_get_u32(tb[RTA_IIF]);
2187 if (tb[RTA_OIF])
2188 fl.oif = nla_get_u32(tb[RTA_OIF]);
2190 if (iif) {
2191 struct net_device *dev;
2192 dev = __dev_get_by_index(iif);
2193 if (!dev) {
2194 err = -ENODEV;
2195 goto errout;
2199 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2200 if (skb == NULL) {
2201 err = -ENOBUFS;
2202 goto errout;
2205 /* Reserve room for dummy headers, this skb can pass
2206 through good chunk of routing engine.
2208 skb->mac.raw = skb->data;
2209 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2211 rt = (struct rt6_info*) ip6_route_output(NULL, &fl);
2212 skb->dst = &rt->u.dst;
2214 err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
2215 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2216 nlh->nlmsg_seq, 0, 0);
2217 if (err < 0) {
2218 kfree_skb(skb);
2219 goto errout;
2222 err = rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
2223 errout:
2224 return err;
2227 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2229 struct sk_buff *skb;
2230 u32 pid = 0, seq = 0;
2231 struct nlmsghdr *nlh = NULL;
2232 int err = -ENOBUFS;
2234 if (info) {
2235 pid = info->pid;
2236 nlh = info->nlh;
2237 if (nlh)
2238 seq = nlh->nlmsg_seq;
2241 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2242 if (skb == NULL)
2243 goto errout;
2245 err = rt6_fill_node(skb, rt, NULL, NULL, 0, event, pid, seq, 0, 0);
2246 /* failure implies BUG in rt6_nlmsg_size() */
2247 BUG_ON(err < 0);
2249 err = rtnl_notify(skb, pid, RTNLGRP_IPV6_ROUTE, nlh, gfp_any());
2250 errout:
2251 if (err < 0)
2252 rtnl_set_sk_err(RTNLGRP_IPV6_ROUTE, err);
2256 * /proc
2259 #ifdef CONFIG_PROC_FS
2261 #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)
2263 struct rt6_proc_arg
2265 char *buffer;
2266 int offset;
2267 int length;
2268 int skip;
2269 int len;
2272 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2274 struct rt6_proc_arg *arg = (struct rt6_proc_arg *) p_arg;
2276 if (arg->skip < arg->offset / RT6_INFO_LEN) {
2277 arg->skip++;
2278 return 0;
2281 if (arg->len >= arg->length)
2282 return 0;
2284 arg->len += sprintf(arg->buffer + arg->len,
2285 NIP6_SEQFMT " %02x ",
2286 NIP6(rt->rt6i_dst.addr),
2287 rt->rt6i_dst.plen);
2289 #ifdef CONFIG_IPV6_SUBTREES
2290 arg->len += sprintf(arg->buffer + arg->len,
2291 NIP6_SEQFMT " %02x ",
2292 NIP6(rt->rt6i_src.addr),
2293 rt->rt6i_src.plen);
2294 #else
2295 arg->len += sprintf(arg->buffer + arg->len,
2296 "00000000000000000000000000000000 00 ");
2297 #endif
2299 if (rt->rt6i_nexthop) {
2300 arg->len += sprintf(arg->buffer + arg->len,
2301 NIP6_SEQFMT,
2302 NIP6(*((struct in6_addr *)rt->rt6i_nexthop->primary_key)));
2303 } else {
2304 arg->len += sprintf(arg->buffer + arg->len,
2305 "00000000000000000000000000000000");
2307 arg->len += sprintf(arg->buffer + arg->len,
2308 " %08x %08x %08x %08x %8s\n",
2309 rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2310 rt->u.dst.__use, rt->rt6i_flags,
2311 rt->rt6i_dev ? rt->rt6i_dev->name : "");
2312 return 0;
2315 static int rt6_proc_info(char *buffer, char **start, off_t offset, int length)
2317 struct rt6_proc_arg arg = {
2318 .buffer = buffer,
2319 .offset = offset,
2320 .length = length,
2323 fib6_clean_all(rt6_info_route, 0, &arg);
2325 *start = buffer;
2326 if (offset)
2327 *start += offset % RT6_INFO_LEN;
2329 arg.len -= offset % RT6_INFO_LEN;
2331 if (arg.len > length)
2332 arg.len = length;
2333 if (arg.len < 0)
2334 arg.len = 0;
2336 return arg.len;
2339 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2341 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2342 rt6_stats.fib_nodes, rt6_stats.fib_route_nodes,
2343 rt6_stats.fib_rt_alloc, rt6_stats.fib_rt_entries,
2344 rt6_stats.fib_rt_cache,
2345 atomic_read(&ip6_dst_ops.entries),
2346 rt6_stats.fib_discarded_routes);
2348 return 0;
2351 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2353 return single_open(file, rt6_stats_seq_show, NULL);
2356 static struct file_operations rt6_stats_seq_fops = {
2357 .owner = THIS_MODULE,
2358 .open = rt6_stats_seq_open,
2359 .read = seq_read,
2360 .llseek = seq_lseek,
2361 .release = single_release,
2363 #endif /* CONFIG_PROC_FS */
2365 #ifdef CONFIG_SYSCTL
2367 static int flush_delay;
2369 static
2370 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp,
2371 void __user *buffer, size_t *lenp, loff_t *ppos)
2373 if (write) {
2374 proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
2375 fib6_run_gc(flush_delay <= 0 ? ~0UL : (unsigned long)flush_delay);
2376 return 0;
2377 } else
2378 return -EINVAL;
2381 ctl_table ipv6_route_table[] = {
2383 .ctl_name = NET_IPV6_ROUTE_FLUSH,
2384 .procname = "flush",
2385 .data = &flush_delay,
2386 .maxlen = sizeof(int),
2387 .mode = 0200,
2388 .proc_handler = &ipv6_sysctl_rtcache_flush
2391 .ctl_name = NET_IPV6_ROUTE_GC_THRESH,
2392 .procname = "gc_thresh",
2393 .data = &ip6_dst_ops.gc_thresh,
2394 .maxlen = sizeof(int),
2395 .mode = 0644,
2396 .proc_handler = &proc_dointvec,
2399 .ctl_name = NET_IPV6_ROUTE_MAX_SIZE,
2400 .procname = "max_size",
2401 .data = &ip6_rt_max_size,
2402 .maxlen = sizeof(int),
2403 .mode = 0644,
2404 .proc_handler = &proc_dointvec,
2407 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL,
2408 .procname = "gc_min_interval",
2409 .data = &ip6_rt_gc_min_interval,
2410 .maxlen = sizeof(int),
2411 .mode = 0644,
2412 .proc_handler = &proc_dointvec_jiffies,
2413 .strategy = &sysctl_jiffies,
2416 .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT,
2417 .procname = "gc_timeout",
2418 .data = &ip6_rt_gc_timeout,
2419 .maxlen = sizeof(int),
2420 .mode = 0644,
2421 .proc_handler = &proc_dointvec_jiffies,
2422 .strategy = &sysctl_jiffies,
2425 .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL,
2426 .procname = "gc_interval",
2427 .data = &ip6_rt_gc_interval,
2428 .maxlen = sizeof(int),
2429 .mode = 0644,
2430 .proc_handler = &proc_dointvec_jiffies,
2431 .strategy = &sysctl_jiffies,
2434 .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY,
2435 .procname = "gc_elasticity",
2436 .data = &ip6_rt_gc_elasticity,
2437 .maxlen = sizeof(int),
2438 .mode = 0644,
2439 .proc_handler = &proc_dointvec_jiffies,
2440 .strategy = &sysctl_jiffies,
2443 .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES,
2444 .procname = "mtu_expires",
2445 .data = &ip6_rt_mtu_expires,
2446 .maxlen = sizeof(int),
2447 .mode = 0644,
2448 .proc_handler = &proc_dointvec_jiffies,
2449 .strategy = &sysctl_jiffies,
2452 .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS,
2453 .procname = "min_adv_mss",
2454 .data = &ip6_rt_min_advmss,
2455 .maxlen = sizeof(int),
2456 .mode = 0644,
2457 .proc_handler = &proc_dointvec_jiffies,
2458 .strategy = &sysctl_jiffies,
2461 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS,
2462 .procname = "gc_min_interval_ms",
2463 .data = &ip6_rt_gc_min_interval,
2464 .maxlen = sizeof(int),
2465 .mode = 0644,
2466 .proc_handler = &proc_dointvec_ms_jiffies,
2467 .strategy = &sysctl_ms_jiffies,
2469 { .ctl_name = 0 }
2472 #endif
2474 void __init ip6_route_init(void)
2476 struct proc_dir_entry *p;
2478 ip6_dst_ops.kmem_cachep =
2479 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2480 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
2481 fib6_init();
2482 #ifdef CONFIG_PROC_FS
2483 p = proc_net_create("ipv6_route", 0, rt6_proc_info);
2484 if (p)
2485 p->owner = THIS_MODULE;
2487 proc_net_fops_create("rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2488 #endif
2489 #ifdef CONFIG_XFRM
2490 xfrm6_init();
2491 #endif
2492 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2493 fib6_rules_init();
2494 #endif
2497 void ip6_route_cleanup(void)
2499 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2500 fib6_rules_cleanup();
2501 #endif
2502 #ifdef CONFIG_PROC_FS
2503 proc_net_remove("ipv6_route");
2504 proc_net_remove("rt6_stats");
2505 #endif
2506 #ifdef CONFIG_XFRM
2507 xfrm6_fini();
2508 #endif
2509 rt6_ifdown(NULL);
2510 fib6_gc_cleanup();
2511 kmem_cache_destroy(ip6_dst_ops.kmem_cachep);