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inet: constify ip headers and in6_addr
[linux-2.6/kvm.git] / net / ipv6 / route.c
blob852fc28ca81808087c187f7a676d5be884f4ef2b
1 /*
2 * Linux INET6 implementation
3 * FIB front-end.
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 */
13
14 /* Changes:
15 *
16 * YOSHIFUJI Hideaki @USAGI
17 * reworked default router selection.
18 * - respect outgoing interface
19 * - select from (probably) reachable routers (i.e.
20 * routers in REACHABLE, STALE, DELAY or PROBE states).
21 * - always select the same router if it is (probably)
22 * reachable. otherwise, round-robin the list.
23 * Ville Nuorvala
24 * Fixed routing subtrees.
25 */
26
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/mroute6.h>
38 #include <linux/init.h>
39 #include <linux/if_arp.h>
40 #include <linux/proc_fs.h>
41 #include <linux/seq_file.h>
42 #include <linux/nsproxy.h>
43 #include <linux/slab.h>
44 #include <net/net_namespace.h>
45 #include <net/snmp.h>
46 #include <net/ipv6.h>
47 #include <net/ip6_fib.h>
48 #include <net/ip6_route.h>
49 #include <net/ndisc.h>
50 #include <net/addrconf.h>
51 #include <net/tcp.h>
52 #include <linux/rtnetlink.h>
53 #include <net/dst.h>
54 #include <net/xfrm.h>
55 #include <net/netevent.h>
56 #include <net/netlink.h>
57
58 #include <asm/uaccess.h>
59
60 #ifdef CONFIG_SYSCTL
61 #include <linux/sysctl.h>
62 #endif
63
64 /* Set to 3 to get tracing. */
65 #define RT6_DEBUG 2
66
67 #if RT6_DEBUG >= 3
68 #define RDBG(x) printk x
69 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
70 #else
71 #define RDBG(x)
72 #define RT6_TRACE(x...) do { ; } while (0)
73 #endif
74
75 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
76 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
77 static unsigned int ip6_default_advmss(const struct dst_entry *dst);
78 static unsigned int ip6_default_mtu(const struct dst_entry *dst);
79 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
80 static void ip6_dst_destroy(struct dst_entry *);
81 static void ip6_dst_ifdown(struct dst_entry *,
82 struct net_device *dev, int how);
83 static int ip6_dst_gc(struct dst_ops *ops);
84
85 static int ip6_pkt_discard(struct sk_buff *skb);
86 static int ip6_pkt_discard_out(struct sk_buff *skb);
87 static void ip6_link_failure(struct sk_buff *skb);
88 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
89
90 #ifdef CONFIG_IPV6_ROUTE_INFO
91 static struct rt6_info *rt6_add_route_info(struct net *net,
92 const struct in6_addr *prefix, int prefixlen,
93 const struct in6_addr *gwaddr, int ifindex,
94 unsigned pref);
95 static struct rt6_info *rt6_get_route_info(struct net *net,
96 const struct in6_addr *prefix, int prefixlen,
97 const struct in6_addr *gwaddr, int ifindex);
98 #endif
99
100 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
101 {
102 struct rt6_info *rt = (struct rt6_info *) dst;
103 struct inet_peer *peer;
104 u32 *p = NULL;
105
106 if (!rt->rt6i_peer)
107 rt6_bind_peer(rt, 1);
108
109 peer = rt->rt6i_peer;
110 if (peer) {
111 u32 *old_p = __DST_METRICS_PTR(old);
112 unsigned long prev, new;
113
114 p = peer->metrics;
115 if (inet_metrics_new(peer))
116 memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
117
118 new = (unsigned long) p;
119 prev = cmpxchg(&dst->_metrics, old, new);
120
121 if (prev != old) {
122 p = __DST_METRICS_PTR(prev);
123 if (prev & DST_METRICS_READ_ONLY)
124 p = NULL;
125 }
126 }
127 return p;
128 }
129
130 static struct dst_ops ip6_dst_ops_template = {
131 .family = AF_INET6,
132 .protocol = cpu_to_be16(ETH_P_IPV6),
133 .gc = ip6_dst_gc,
134 .gc_thresh = 1024,
135 .check = ip6_dst_check,
136 .default_advmss = ip6_default_advmss,
137 .default_mtu = ip6_default_mtu,
138 .cow_metrics = ipv6_cow_metrics,
139 .destroy = ip6_dst_destroy,
140 .ifdown = ip6_dst_ifdown,
141 .negative_advice = ip6_negative_advice,
142 .link_failure = ip6_link_failure,
143 .update_pmtu = ip6_rt_update_pmtu,
144 .local_out = __ip6_local_out,
145 };
146
147 static unsigned int ip6_blackhole_default_mtu(const struct dst_entry *dst)
148 {
149 return 0;
150 }
151
152 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
153 {
154 }
155
156 static struct dst_ops ip6_dst_blackhole_ops = {
157 .family = AF_INET6,
158 .protocol = cpu_to_be16(ETH_P_IPV6),
159 .destroy = ip6_dst_destroy,
160 .check = ip6_dst_check,
161 .default_mtu = ip6_blackhole_default_mtu,
162 .default_advmss = ip6_default_advmss,
163 .update_pmtu = ip6_rt_blackhole_update_pmtu,
164 };
165
166 static const u32 ip6_template_metrics[RTAX_MAX] = {
167 [RTAX_HOPLIMIT - 1] = 255,
168 };
169
170 static struct rt6_info ip6_null_entry_template = {
171 .dst = {
172 .__refcnt = ATOMIC_INIT(1),
173 .__use = 1,
174 .obsolete = -1,
175 .error = -ENETUNREACH,
176 .input = ip6_pkt_discard,
177 .output = ip6_pkt_discard_out,
178 },
179 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
180 .rt6i_protocol = RTPROT_KERNEL,
181 .rt6i_metric = ~(u32) 0,
182 .rt6i_ref = ATOMIC_INIT(1),
183 };
184
185 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
186
187 static int ip6_pkt_prohibit(struct sk_buff *skb);
188 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
189
190 static struct rt6_info ip6_prohibit_entry_template = {
191 .dst = {
192 .__refcnt = ATOMIC_INIT(1),
193 .__use = 1,
194 .obsolete = -1,
195 .error = -EACCES,
196 .input = ip6_pkt_prohibit,
197 .output = ip6_pkt_prohibit_out,
198 },
199 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
200 .rt6i_protocol = RTPROT_KERNEL,
201 .rt6i_metric = ~(u32) 0,
202 .rt6i_ref = ATOMIC_INIT(1),
203 };
204
205 static struct rt6_info ip6_blk_hole_entry_template = {
206 .dst = {
207 .__refcnt = ATOMIC_INIT(1),
208 .__use = 1,
209 .obsolete = -1,
210 .error = -EINVAL,
211 .input = dst_discard,
212 .output = dst_discard,
213 },
214 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
215 .rt6i_protocol = RTPROT_KERNEL,
216 .rt6i_metric = ~(u32) 0,
217 .rt6i_ref = ATOMIC_INIT(1),
218 };
219
220 #endif
221
222 /* allocate dst with ip6_dst_ops */
223 static inline struct rt6_info *ip6_dst_alloc(struct dst_ops *ops)
224 {
225 return (struct rt6_info *)dst_alloc(ops, 0);
226 }
227
228 static void ip6_dst_destroy(struct dst_entry *dst)
229 {
230 struct rt6_info *rt = (struct rt6_info *)dst;
231 struct inet6_dev *idev = rt->rt6i_idev;
232 struct inet_peer *peer = rt->rt6i_peer;
233
234 if (idev != NULL) {
235 rt->rt6i_idev = NULL;
236 in6_dev_put(idev);
237 }
238 if (peer) {
239 rt->rt6i_peer = NULL;
240 inet_putpeer(peer);
241 }
242 }
243
244 static atomic_t __rt6_peer_genid = ATOMIC_INIT(0);
245
246 static u32 rt6_peer_genid(void)
247 {
248 return atomic_read(&__rt6_peer_genid);
249 }
250
251 void rt6_bind_peer(struct rt6_info *rt, int create)
252 {
253 struct inet_peer *peer;
254
255 peer = inet_getpeer_v6(&rt->rt6i_dst.addr, create);
256 if (peer && cmpxchg(&rt->rt6i_peer, NULL, peer) != NULL)
257 inet_putpeer(peer);
258 else
259 rt->rt6i_peer_genid = rt6_peer_genid();
260 }
261
262 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
263 int how)
264 {
265 struct rt6_info *rt = (struct rt6_info *)dst;
266 struct inet6_dev *idev = rt->rt6i_idev;
267 struct net_device *loopback_dev =
268 dev_net(dev)->loopback_dev;
269
270 if (dev != loopback_dev && idev != NULL && idev->dev == dev) {
271 struct inet6_dev *loopback_idev =
272 in6_dev_get(loopback_dev);
273 if (loopback_idev != NULL) {
274 rt->rt6i_idev = loopback_idev;
275 in6_dev_put(idev);
276 }
277 }
278 }
279
280 static __inline__ int rt6_check_expired(const struct rt6_info *rt)
281 {
282 return (rt->rt6i_flags & RTF_EXPIRES) &&
283 time_after(jiffies, rt->rt6i_expires);
284 }
285
286 static inline int rt6_need_strict(const struct in6_addr *daddr)
287 {
288 return ipv6_addr_type(daddr) &
289 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
290 }
291
292 /*
293 * Route lookup. Any table->tb6_lock is implied.
294 */
295
296 static inline struct rt6_info *rt6_device_match(struct net *net,
297 struct rt6_info *rt,
298 const struct in6_addr *saddr,
299 int oif,
300 int flags)
301 {
302 struct rt6_info *local = NULL;
303 struct rt6_info *sprt;
304
305 if (!oif && ipv6_addr_any(saddr))
306 goto out;
307
308 for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
309 struct net_device *dev = sprt->rt6i_dev;
310
311 if (oif) {
312 if (dev->ifindex == oif)
313 return sprt;
314 if (dev->flags & IFF_LOOPBACK) {
315 if (sprt->rt6i_idev == NULL ||
316 sprt->rt6i_idev->dev->ifindex != oif) {
317 if (flags & RT6_LOOKUP_F_IFACE && oif)
318 continue;
319 if (local && (!oif ||
320 local->rt6i_idev->dev->ifindex == oif))
321 continue;
322 }
323 local = sprt;
324 }
325 } else {
326 if (ipv6_chk_addr(net, saddr, dev,
327 flags & RT6_LOOKUP_F_IFACE))
328 return sprt;
329 }
330 }
331
332 if (oif) {
333 if (local)
334 return local;
335
336 if (flags & RT6_LOOKUP_F_IFACE)
337 return net->ipv6.ip6_null_entry;
338 }
339 out:
340 return rt;
341 }
342
343 #ifdef CONFIG_IPV6_ROUTER_PREF
344 static void rt6_probe(struct rt6_info *rt)
345 {
346 struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
347 /*
348 * Okay, this does not seem to be appropriate
349 * for now, however, we need to check if it
350 * is really so; aka Router Reachability Probing.
351 *
352 * Router Reachability Probe MUST be rate-limited
353 * to no more than one per minute.
354 */
355 if (!neigh || (neigh->nud_state & NUD_VALID))
356 return;
357 read_lock_bh(&neigh->lock);
358 if (!(neigh->nud_state & NUD_VALID) &&
359 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
360 struct in6_addr mcaddr;
361 struct in6_addr *target;
362
363 neigh->updated = jiffies;
364 read_unlock_bh(&neigh->lock);
365
366 target = (struct in6_addr *)&neigh->primary_key;
367 addrconf_addr_solict_mult(target, &mcaddr);
368 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
369 } else
370 read_unlock_bh(&neigh->lock);
371 }
372 #else
373 static inline void rt6_probe(struct rt6_info *rt)
374 {
375 }
376 #endif
377
378 /*
379 * Default Router Selection (RFC 2461 6.3.6)
380 */
381 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
382 {
383 struct net_device *dev = rt->rt6i_dev;
384 if (!oif || dev->ifindex == oif)
385 return 2;
386 if ((dev->flags & IFF_LOOPBACK) &&
387 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
388 return 1;
389 return 0;
390 }
391
392 static inline int rt6_check_neigh(struct rt6_info *rt)
393 {
394 struct neighbour *neigh = rt->rt6i_nexthop;
395 int m;
396 if (rt->rt6i_flags & RTF_NONEXTHOP ||
397 !(rt->rt6i_flags & RTF_GATEWAY))
398 m = 1;
399 else if (neigh) {
400 read_lock_bh(&neigh->lock);
401 if (neigh->nud_state & NUD_VALID)
402 m = 2;
403 #ifdef CONFIG_IPV6_ROUTER_PREF
404 else if (neigh->nud_state & NUD_FAILED)
405 m = 0;
406 #endif
407 else
408 m = 1;
409 read_unlock_bh(&neigh->lock);
410 } else
411 m = 0;
412 return m;
413 }
414
415 static int rt6_score_route(struct rt6_info *rt, int oif,
416 int strict)
417 {
418 int m, n;
419
420 m = rt6_check_dev(rt, oif);
421 if (!m && (strict & RT6_LOOKUP_F_IFACE))
422 return -1;
423 #ifdef CONFIG_IPV6_ROUTER_PREF
424 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
425 #endif
426 n = rt6_check_neigh(rt);
427 if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
428 return -1;
429 return m;
430 }
431
432 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
433 int *mpri, struct rt6_info *match)
434 {
435 int m;
436
437 if (rt6_check_expired(rt))
438 goto out;
439
440 m = rt6_score_route(rt, oif, strict);
441 if (m < 0)
442 goto out;
443
444 if (m > *mpri) {
445 if (strict & RT6_LOOKUP_F_REACHABLE)
446 rt6_probe(match);
447 *mpri = m;
448 match = rt;
449 } else if (strict & RT6_LOOKUP_F_REACHABLE) {
450 rt6_probe(rt);
451 }
452
453 out:
454 return match;
455 }
456
457 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
458 struct rt6_info *rr_head,
459 u32 metric, int oif, int strict)
460 {
461 struct rt6_info *rt, *match;
462 int mpri = -1;
463
464 match = NULL;
465 for (rt = rr_head; rt && rt->rt6i_metric == metric;
466 rt = rt->dst.rt6_next)
467 match = find_match(rt, oif, strict, &mpri, match);
468 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
469 rt = rt->dst.rt6_next)
470 match = find_match(rt, oif, strict, &mpri, match);
471
472 return match;
473 }
474
475 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
476 {
477 struct rt6_info *match, *rt0;
478 struct net *net;
479
480 RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
481 __func__, fn->leaf, oif);
482
483 rt0 = fn->rr_ptr;
484 if (!rt0)
485 fn->rr_ptr = rt0 = fn->leaf;
486
487 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
488
489 if (!match &&
490 (strict & RT6_LOOKUP_F_REACHABLE)) {
491 struct rt6_info *next = rt0->dst.rt6_next;
492
493 /* no entries matched; do round-robin */
494 if (!next || next->rt6i_metric != rt0->rt6i_metric)
495 next = fn->leaf;
496
497 if (next != rt0)
498 fn->rr_ptr = next;
499 }
500
501 RT6_TRACE("%s() => %p\n",
502 __func__, match);
503
504 net = dev_net(rt0->rt6i_dev);
505 return match ? match : net->ipv6.ip6_null_entry;
506 }
507
508 #ifdef CONFIG_IPV6_ROUTE_INFO
509 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
510 const struct in6_addr *gwaddr)
511 {
512 struct net *net = dev_net(dev);
513 struct route_info *rinfo = (struct route_info *) opt;
514 struct in6_addr prefix_buf, *prefix;
515 unsigned int pref;
516 unsigned long lifetime;
517 struct rt6_info *rt;
518
519 if (len < sizeof(struct route_info)) {
520 return -EINVAL;
521 }
522
523 /* Sanity check for prefix_len and length */
524 if (rinfo->length > 3) {
525 return -EINVAL;
526 } else if (rinfo->prefix_len > 128) {
527 return -EINVAL;
528 } else if (rinfo->prefix_len > 64) {
529 if (rinfo->length < 2) {
530 return -EINVAL;
531 }
532 } else if (rinfo->prefix_len > 0) {
533 if (rinfo->length < 1) {
534 return -EINVAL;
535 }
536 }
537
538 pref = rinfo->route_pref;
539 if (pref == ICMPV6_ROUTER_PREF_INVALID)
540 return -EINVAL;
541
542 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
543
544 if (rinfo->length == 3)
545 prefix = (struct in6_addr *)rinfo->prefix;
546 else {
547 /* this function is safe */
548 ipv6_addr_prefix(&prefix_buf,
549 (struct in6_addr *)rinfo->prefix,
550 rinfo->prefix_len);
551 prefix = &prefix_buf;
552 }
553
554 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr,
555 dev->ifindex);
556
557 if (rt && !lifetime) {
558 ip6_del_rt(rt);
559 rt = NULL;
560 }
561
562 if (!rt && lifetime)
563 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
564 pref);
565 else if (rt)
566 rt->rt6i_flags = RTF_ROUTEINFO |
567 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
568
569 if (rt) {
570 if (!addrconf_finite_timeout(lifetime)) {
571 rt->rt6i_flags &= ~RTF_EXPIRES;
572 } else {
573 rt->rt6i_expires = jiffies + HZ * lifetime;
574 rt->rt6i_flags |= RTF_EXPIRES;
575 }
576 dst_release(&rt->dst);
577 }
578 return 0;
579 }
580 #endif
581
582 #define BACKTRACK(__net, saddr) \
583 do { \
584 if (rt == __net->ipv6.ip6_null_entry) { \
585 struct fib6_node *pn; \
586 while (1) { \
587 if (fn->fn_flags & RTN_TL_ROOT) \
588 goto out; \
589 pn = fn->parent; \
590 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
591 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
592 else \
593 fn = pn; \
594 if (fn->fn_flags & RTN_RTINFO) \
595 goto restart; \
596 } \
597 } \
598 } while(0)
599
600 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
601 struct fib6_table *table,
602 struct flowi6 *fl6, int flags)
603 {
604 struct fib6_node *fn;
605 struct rt6_info *rt;
606
607 read_lock_bh(&table->tb6_lock);
608 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
609 restart:
610 rt = fn->leaf;
611 rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
612 BACKTRACK(net, &fl6->saddr);
613 out:
614 dst_use(&rt->dst, jiffies);
615 read_unlock_bh(&table->tb6_lock);
616 return rt;
617
618 }
619
620 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
621 const struct in6_addr *saddr, int oif, int strict)
622 {
623 struct flowi6 fl6 = {
624 .flowi6_oif = oif,
625 .daddr = *daddr,
626 };
627 struct dst_entry *dst;
628 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
629
630 if (saddr) {
631 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
632 flags |= RT6_LOOKUP_F_HAS_SADDR;
633 }
634
635 dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
636 if (dst->error == 0)
637 return (struct rt6_info *) dst;
638
639 dst_release(dst);
640
641 return NULL;
642 }
643
644 EXPORT_SYMBOL(rt6_lookup);
645
646 /* ip6_ins_rt is called with FREE table->tb6_lock.
647 It takes new route entry, the addition fails by any reason the
648 route is freed. In any case, if caller does not hold it, it may
649 be destroyed.
650 */
651
652 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
653 {
654 int err;
655 struct fib6_table *table;
656
657 table = rt->rt6i_table;
658 write_lock_bh(&table->tb6_lock);
659 err = fib6_add(&table->tb6_root, rt, info);
660 write_unlock_bh(&table->tb6_lock);
661
662 return err;
663 }
664
665 int ip6_ins_rt(struct rt6_info *rt)
666 {
667 struct nl_info info = {
668 .nl_net = dev_net(rt->rt6i_dev),
669 };
670 return __ip6_ins_rt(rt, &info);
671 }
672
673 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, const struct in6_addr *daddr,
674 const struct in6_addr *saddr)
675 {
676 struct rt6_info *rt;
677
678 /*
679 * Clone the route.
680 */
681
682 rt = ip6_rt_copy(ort);
683
684 if (rt) {
685 struct neighbour *neigh;
686 int attempts = !in_softirq();
687
688 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
689 if (rt->rt6i_dst.plen != 128 &&
690 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
691 rt->rt6i_flags |= RTF_ANYCAST;
692 ipv6_addr_copy(&rt->rt6i_gateway, daddr);
693 }
694
695 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
696 rt->rt6i_dst.plen = 128;
697 rt->rt6i_flags |= RTF_CACHE;
698 rt->dst.flags |= DST_HOST;
699
700 #ifdef CONFIG_IPV6_SUBTREES
701 if (rt->rt6i_src.plen && saddr) {
702 ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
703 rt->rt6i_src.plen = 128;
704 }
705 #endif
706
707 retry:
708 neigh = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
709 if (IS_ERR(neigh)) {
710 struct net *net = dev_net(rt->rt6i_dev);
711 int saved_rt_min_interval =
712 net->ipv6.sysctl.ip6_rt_gc_min_interval;
713 int saved_rt_elasticity =
714 net->ipv6.sysctl.ip6_rt_gc_elasticity;
715
716 if (attempts-- > 0) {
717 net->ipv6.sysctl.ip6_rt_gc_elasticity = 1;
718 net->ipv6.sysctl.ip6_rt_gc_min_interval = 0;
719
720 ip6_dst_gc(&net->ipv6.ip6_dst_ops);
721
722 net->ipv6.sysctl.ip6_rt_gc_elasticity =
723 saved_rt_elasticity;
724 net->ipv6.sysctl.ip6_rt_gc_min_interval =
725 saved_rt_min_interval;
726 goto retry;
727 }
728
729 if (net_ratelimit())
730 printk(KERN_WARNING
731 "ipv6: Neighbour table overflow.\n");
732 dst_free(&rt->dst);
733 return NULL;
734 }
735 rt->rt6i_nexthop = neigh;
736
737 }
738
739 return rt;
740 }
741
742 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, const struct in6_addr *daddr)
743 {
744 struct rt6_info *rt = ip6_rt_copy(ort);
745 if (rt) {
746 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
747 rt->rt6i_dst.plen = 128;
748 rt->rt6i_flags |= RTF_CACHE;
749 rt->dst.flags |= DST_HOST;
750 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
751 }
752 return rt;
753 }
754
755 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
756 struct flowi6 *fl6, int flags)
757 {
758 struct fib6_node *fn;
759 struct rt6_info *rt, *nrt;
760 int strict = 0;
761 int attempts = 3;
762 int err;
763 int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
764
765 strict |= flags & RT6_LOOKUP_F_IFACE;
766
767 relookup:
768 read_lock_bh(&table->tb6_lock);
769
770 restart_2:
771 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
772
773 restart:
774 rt = rt6_select(fn, oif, strict | reachable);
775
776 BACKTRACK(net, &fl6->saddr);
777 if (rt == net->ipv6.ip6_null_entry ||
778 rt->rt6i_flags & RTF_CACHE)
779 goto out;
780
781 dst_hold(&rt->dst);
782 read_unlock_bh(&table->tb6_lock);
783
784 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
785 nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr);
786 else if (!(rt->dst.flags & DST_HOST))
787 nrt = rt6_alloc_clone(rt, &fl6->daddr);
788 else
789 goto out2;
790
791 dst_release(&rt->dst);
792 rt = nrt ? : net->ipv6.ip6_null_entry;
793
794 dst_hold(&rt->dst);
795 if (nrt) {
796 err = ip6_ins_rt(nrt);
797 if (!err)
798 goto out2;
799 }
800
801 if (--attempts <= 0)
802 goto out2;
803
804 /*
805 * Race condition! In the gap, when table->tb6_lock was
806 * released someone could insert this route. Relookup.
807 */
808 dst_release(&rt->dst);
809 goto relookup;
810
811 out:
812 if (reachable) {
813 reachable = 0;
814 goto restart_2;
815 }
816 dst_hold(&rt->dst);
817 read_unlock_bh(&table->tb6_lock);
818 out2:
819 rt->dst.lastuse = jiffies;
820 rt->dst.__use++;
821
822 return rt;
823 }
824
825 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
826 struct flowi6 *fl6, int flags)
827 {
828 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
829 }
830
831 void ip6_route_input(struct sk_buff *skb)
832 {
833 const struct ipv6hdr *iph = ipv6_hdr(skb);
834 struct net *net = dev_net(skb->dev);
835 int flags = RT6_LOOKUP_F_HAS_SADDR;
836 struct flowi6 fl6 = {
837 .flowi6_iif = skb->dev->ifindex,
838 .daddr = iph->daddr,
839 .saddr = iph->saddr,
840 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
841 .flowi6_mark = skb->mark,
842 .flowi6_proto = iph->nexthdr,
843 };
844
845 if (rt6_need_strict(&iph->daddr) && skb->dev->type != ARPHRD_PIMREG)
846 flags |= RT6_LOOKUP_F_IFACE;
847
848 skb_dst_set(skb, fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_input));
849 }
850
851 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
852 struct flowi6 *fl6, int flags)
853 {
854 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
855 }
856
857 struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk,
858 struct flowi6 *fl6)
859 {
860 int flags = 0;
861
862 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr))
863 flags |= RT6_LOOKUP_F_IFACE;
864
865 if (!ipv6_addr_any(&fl6->saddr))
866 flags |= RT6_LOOKUP_F_HAS_SADDR;
867 else if (sk)
868 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
869
870 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
871 }
872
873 EXPORT_SYMBOL(ip6_route_output);
874
875 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
876 {
877 struct rt6_info *rt = dst_alloc(&ip6_dst_blackhole_ops, 1);
878 struct rt6_info *ort = (struct rt6_info *) dst_orig;
879 struct dst_entry *new = NULL;
880
881 if (rt) {
882 new = &rt->dst;
883
884 new->__use = 1;
885 new->input = dst_discard;
886 new->output = dst_discard;
887
888 dst_copy_metrics(new, &ort->dst);
889 new->dev = ort->dst.dev;
890 if (new->dev)
891 dev_hold(new->dev);
892 rt->rt6i_idev = ort->rt6i_idev;
893 if (rt->rt6i_idev)
894 in6_dev_hold(rt->rt6i_idev);
895 rt->rt6i_expires = 0;
896
897 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
898 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
899 rt->rt6i_metric = 0;
900
901 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
902 #ifdef CONFIG_IPV6_SUBTREES
903 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
904 #endif
905
906 dst_free(new);
907 }
908
909 dst_release(dst_orig);
910 return new ? new : ERR_PTR(-ENOMEM);
911 }
912
913 /*
914 * Destination cache support functions
915 */
916
917 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
918 {
919 struct rt6_info *rt;
920
921 rt = (struct rt6_info *) dst;
922
923 if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) {
924 if (rt->rt6i_peer_genid != rt6_peer_genid()) {
925 if (!rt->rt6i_peer)
926 rt6_bind_peer(rt, 0);
927 rt->rt6i_peer_genid = rt6_peer_genid();
928 }
929 return dst;
930 }
931 return NULL;
932 }
933
934 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
935 {
936 struct rt6_info *rt = (struct rt6_info *) dst;
937
938 if (rt) {
939 if (rt->rt6i_flags & RTF_CACHE) {
940 if (rt6_check_expired(rt)) {
941 ip6_del_rt(rt);
942 dst = NULL;
943 }
944 } else {
945 dst_release(dst);
946 dst = NULL;
947 }
948 }
949 return dst;
950 }
951
952 static void ip6_link_failure(struct sk_buff *skb)
953 {
954 struct rt6_info *rt;
955
956 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
957
958 rt = (struct rt6_info *) skb_dst(skb);
959 if (rt) {
960 if (rt->rt6i_flags&RTF_CACHE) {
961 dst_set_expires(&rt->dst, 0);
962 rt->rt6i_flags |= RTF_EXPIRES;
963 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
964 rt->rt6i_node->fn_sernum = -1;
965 }
966 }
967
968 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
969 {
970 struct rt6_info *rt6 = (struct rt6_info*)dst;
971
972 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
973 rt6->rt6i_flags |= RTF_MODIFIED;
974 if (mtu < IPV6_MIN_MTU) {
975 u32 features = dst_metric(dst, RTAX_FEATURES);
976 mtu = IPV6_MIN_MTU;
977 features |= RTAX_FEATURE_ALLFRAG;
978 dst_metric_set(dst, RTAX_FEATURES, features);
979 }
980 dst_metric_set(dst, RTAX_MTU, mtu);
981 }
982 }
983
984 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
985 {
986 struct net_device *dev = dst->dev;
987 unsigned int mtu = dst_mtu(dst);
988 struct net *net = dev_net(dev);
989
990 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
991
992 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
993 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
994
995 /*
996 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
997 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
998 * IPV6_MAXPLEN is also valid and means: "any MSS,
999 * rely only on pmtu discovery"
1000 */
1001 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1002 mtu = IPV6_MAXPLEN;
1003 return mtu;
1004 }
1005
1006 static unsigned int ip6_default_mtu(const struct dst_entry *dst)
1007 {
1008 unsigned int mtu = IPV6_MIN_MTU;
1009 struct inet6_dev *idev;
1010
1011 rcu_read_lock();
1012 idev = __in6_dev_get(dst->dev);
1013 if (idev)
1014 mtu = idev->cnf.mtu6;
1015 rcu_read_unlock();
1016
1017 return mtu;
1018 }
1019
1020 static struct dst_entry *icmp6_dst_gc_list;
1021 static DEFINE_SPINLOCK(icmp6_dst_lock);
1022
1023 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1024 struct neighbour *neigh,
1025 const struct in6_addr *addr)
1026 {
1027 struct rt6_info *rt;
1028 struct inet6_dev *idev = in6_dev_get(dev);
1029 struct net *net = dev_net(dev);
1030
1031 if (unlikely(idev == NULL))
1032 return NULL;
1033
1034 rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
1035 if (unlikely(rt == NULL)) {
1036 in6_dev_put(idev);
1037 goto out;
1038 }
1039
1040 dev_hold(dev);
1041 if (neigh)
1042 neigh_hold(neigh);
1043 else {
1044 neigh = ndisc_get_neigh(dev, addr);
1045 if (IS_ERR(neigh))
1046 neigh = NULL;
1047 }
1048
1049 rt->rt6i_dev = dev;
1050 rt->rt6i_idev = idev;
1051 rt->rt6i_nexthop = neigh;
1052 atomic_set(&rt->dst.__refcnt, 1);
1053 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255);
1054 rt->dst.output = ip6_output;
1055
1056 #if 0 /* there's no chance to use these for ndisc */
1057 rt->dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
1058 ? DST_HOST
1059 : 0;
1060 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1061 rt->rt6i_dst.plen = 128;
1062 #endif
1063
1064 spin_lock_bh(&icmp6_dst_lock);
1065 rt->dst.next = icmp6_dst_gc_list;
1066 icmp6_dst_gc_list = &rt->dst;
1067 spin_unlock_bh(&icmp6_dst_lock);
1068
1069 fib6_force_start_gc(net);
1070
1071 out:
1072 return &rt->dst;
1073 }
1074
1075 int icmp6_dst_gc(void)
1076 {
1077 struct dst_entry *dst, **pprev;
1078 int more = 0;
1079
1080 spin_lock_bh(&icmp6_dst_lock);
1081 pprev = &icmp6_dst_gc_list;
1082
1083 while ((dst = *pprev) != NULL) {
1084 if (!atomic_read(&dst->__refcnt)) {
1085 *pprev = dst->next;
1086 dst_free(dst);
1087 } else {
1088 pprev = &dst->next;
1089 ++more;
1090 }
1091 }
1092
1093 spin_unlock_bh(&icmp6_dst_lock);
1094
1095 return more;
1096 }
1097
1098 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1099 void *arg)
1100 {
1101 struct dst_entry *dst, **pprev;
1102
1103 spin_lock_bh(&icmp6_dst_lock);
1104 pprev = &icmp6_dst_gc_list;
1105 while ((dst = *pprev) != NULL) {
1106 struct rt6_info *rt = (struct rt6_info *) dst;
1107 if (func(rt, arg)) {
1108 *pprev = dst->next;
1109 dst_free(dst);
1110 } else {
1111 pprev = &dst->next;
1112 }
1113 }
1114 spin_unlock_bh(&icmp6_dst_lock);
1115 }
1116
1117 static int ip6_dst_gc(struct dst_ops *ops)
1118 {
1119 unsigned long now = jiffies;
1120 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1121 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1122 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1123 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1124 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1125 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1126 int entries;
1127
1128 entries = dst_entries_get_fast(ops);
1129 if (time_after(rt_last_gc + rt_min_interval, now) &&
1130 entries <= rt_max_size)
1131 goto out;
1132
1133 net->ipv6.ip6_rt_gc_expire++;
1134 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net);
1135 net->ipv6.ip6_rt_last_gc = now;
1136 entries = dst_entries_get_slow(ops);
1137 if (entries < ops->gc_thresh)
1138 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1139 out:
1140 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1141 return entries > rt_max_size;
1142 }
1143
1144 /* Clean host part of a prefix. Not necessary in radix tree,
1145 but results in cleaner routing tables.
1146
1147 Remove it only when all the things will work!
1148 */
1149
1150 int ip6_dst_hoplimit(struct dst_entry *dst)
1151 {
1152 int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
1153 if (hoplimit == 0) {
1154 struct net_device *dev = dst->dev;
1155 struct inet6_dev *idev;
1156
1157 rcu_read_lock();
1158 idev = __in6_dev_get(dev);
1159 if (idev)
1160 hoplimit = idev->cnf.hop_limit;
1161 else
1162 hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
1163 rcu_read_unlock();
1164 }
1165 return hoplimit;
1166 }
1167 EXPORT_SYMBOL(ip6_dst_hoplimit);
1168
1169 /*
1170 *
1171 */
1172
1173 int ip6_route_add(struct fib6_config *cfg)
1174 {
1175 int err;
1176 struct net *net = cfg->fc_nlinfo.nl_net;
1177 struct rt6_info *rt = NULL;
1178 struct net_device *dev = NULL;
1179 struct inet6_dev *idev = NULL;
1180 struct fib6_table *table;
1181 int addr_type;
1182
1183 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1184 return -EINVAL;
1185 #ifndef CONFIG_IPV6_SUBTREES
1186 if (cfg->fc_src_len)
1187 return -EINVAL;
1188 #endif
1189 if (cfg->fc_ifindex) {
1190 err = -ENODEV;
1191 dev = dev_get_by_index(net, cfg->fc_ifindex);
1192 if (!dev)
1193 goto out;
1194 idev = in6_dev_get(dev);
1195 if (!idev)
1196 goto out;
1197 }
1198
1199 if (cfg->fc_metric == 0)
1200 cfg->fc_metric = IP6_RT_PRIO_USER;
1201
1202 table = fib6_new_table(net, cfg->fc_table);
1203 if (table == NULL) {
1204 err = -ENOBUFS;
1205 goto out;
1206 }
1207
1208 rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
1209
1210 if (rt == NULL) {
1211 err = -ENOMEM;
1212 goto out;
1213 }
1214
1215 rt->dst.obsolete = -1;
1216 rt->rt6i_expires = (cfg->fc_flags & RTF_EXPIRES) ?
1217 jiffies + clock_t_to_jiffies(cfg->fc_expires) :
1218 0;
1219
1220 if (cfg->fc_protocol == RTPROT_UNSPEC)
1221 cfg->fc_protocol = RTPROT_BOOT;
1222 rt->rt6i_protocol = cfg->fc_protocol;
1223
1224 addr_type = ipv6_addr_type(&cfg->fc_dst);
1225
1226 if (addr_type & IPV6_ADDR_MULTICAST)
1227 rt->dst.input = ip6_mc_input;
1228 else if (cfg->fc_flags & RTF_LOCAL)
1229 rt->dst.input = ip6_input;
1230 else
1231 rt->dst.input = ip6_forward;
1232
1233 rt->dst.output = ip6_output;
1234
1235 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1236 rt->rt6i_dst.plen = cfg->fc_dst_len;
1237 if (rt->rt6i_dst.plen == 128)
1238 rt->dst.flags = DST_HOST;
1239
1240 #ifdef CONFIG_IPV6_SUBTREES
1241 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1242 rt->rt6i_src.plen = cfg->fc_src_len;
1243 #endif
1244
1245 rt->rt6i_metric = cfg->fc_metric;
1246
1247 /* We cannot add true routes via loopback here,
1248 they would result in kernel looping; promote them to reject routes
1249 */
1250 if ((cfg->fc_flags & RTF_REJECT) ||
1251 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK)
1252 && !(cfg->fc_flags&RTF_LOCAL))) {
1253 /* hold loopback dev/idev if we haven't done so. */
1254 if (dev != net->loopback_dev) {
1255 if (dev) {
1256 dev_put(dev);
1257 in6_dev_put(idev);
1258 }
1259 dev = net->loopback_dev;
1260 dev_hold(dev);
1261 idev = in6_dev_get(dev);
1262 if (!idev) {
1263 err = -ENODEV;
1264 goto out;
1265 }
1266 }
1267 rt->dst.output = ip6_pkt_discard_out;
1268 rt->dst.input = ip6_pkt_discard;
1269 rt->dst.error = -ENETUNREACH;
1270 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1271 goto install_route;
1272 }
1273
1274 if (cfg->fc_flags & RTF_GATEWAY) {
1275 const struct in6_addr *gw_addr;
1276 int gwa_type;
1277
1278 gw_addr = &cfg->fc_gateway;
1279 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1280 gwa_type = ipv6_addr_type(gw_addr);
1281
1282 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1283 struct rt6_info *grt;
1284
1285 /* IPv6 strictly inhibits using not link-local
1286 addresses as nexthop address.
1287 Otherwise, router will not able to send redirects.
1288 It is very good, but in some (rare!) circumstances
1289 (SIT, PtP, NBMA NOARP links) it is handy to allow
1290 some exceptions. --ANK
1291 */
1292 err = -EINVAL;
1293 if (!(gwa_type&IPV6_ADDR_UNICAST))
1294 goto out;
1295
1296 grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1297
1298 err = -EHOSTUNREACH;
1299 if (grt == NULL)
1300 goto out;
1301 if (dev) {
1302 if (dev != grt->rt6i_dev) {
1303 dst_release(&grt->dst);
1304 goto out;
1305 }
1306 } else {
1307 dev = grt->rt6i_dev;
1308 idev = grt->rt6i_idev;
1309 dev_hold(dev);
1310 in6_dev_hold(grt->rt6i_idev);
1311 }
1312 if (!(grt->rt6i_flags&RTF_GATEWAY))
1313 err = 0;
1314 dst_release(&grt->dst);
1315
1316 if (err)
1317 goto out;
1318 }
1319 err = -EINVAL;
1320 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1321 goto out;
1322 }
1323
1324 err = -ENODEV;
1325 if (dev == NULL)
1326 goto out;
1327
1328 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1329 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1330 err = -EINVAL;
1331 goto out;
1332 }
1333 ipv6_addr_copy(&rt->rt6i_prefsrc.addr, &cfg->fc_prefsrc);
1334 rt->rt6i_prefsrc.plen = 128;
1335 } else
1336 rt->rt6i_prefsrc.plen = 0;
1337
1338 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1339 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1340 if (IS_ERR(rt->rt6i_nexthop)) {
1341 err = PTR_ERR(rt->rt6i_nexthop);
1342 rt->rt6i_nexthop = NULL;
1343 goto out;
1344 }
1345 }
1346
1347 rt->rt6i_flags = cfg->fc_flags;
1348
1349 install_route:
1350 if (cfg->fc_mx) {
1351 struct nlattr *nla;
1352 int remaining;
1353
1354 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1355 int type = nla_type(nla);
1356
1357 if (type) {
1358 if (type > RTAX_MAX) {
1359 err = -EINVAL;
1360 goto out;
1361 }
1362
1363 dst_metric_set(&rt->dst, type, nla_get_u32(nla));
1364 }
1365 }
1366 }
1367
1368 rt->dst.dev = dev;
1369 rt->rt6i_idev = idev;
1370 rt->rt6i_table = table;
1371
1372 cfg->fc_nlinfo.nl_net = dev_net(dev);
1373
1374 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1375
1376 out:
1377 if (dev)
1378 dev_put(dev);
1379 if (idev)
1380 in6_dev_put(idev);
1381 if (rt)
1382 dst_free(&rt->dst);
1383 return err;
1384 }
1385
1386 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1387 {
1388 int err;
1389 struct fib6_table *table;
1390 struct net *net = dev_net(rt->rt6i_dev);
1391
1392 if (rt == net->ipv6.ip6_null_entry)
1393 return -ENOENT;
1394
1395 table = rt->rt6i_table;
1396 write_lock_bh(&table->tb6_lock);
1397
1398 err = fib6_del(rt, info);
1399 dst_release(&rt->dst);
1400
1401 write_unlock_bh(&table->tb6_lock);
1402
1403 return err;
1404 }
1405
1406 int ip6_del_rt(struct rt6_info *rt)
1407 {
1408 struct nl_info info = {
1409 .nl_net = dev_net(rt->rt6i_dev),
1410 };
1411 return __ip6_del_rt(rt, &info);
1412 }
1413
1414 static int ip6_route_del(struct fib6_config *cfg)
1415 {
1416 struct fib6_table *table;
1417 struct fib6_node *fn;
1418 struct rt6_info *rt;
1419 int err = -ESRCH;
1420
1421 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
1422 if (table == NULL)
1423 return err;
1424
1425 read_lock_bh(&table->tb6_lock);
1426
1427 fn = fib6_locate(&table->tb6_root,
1428 &cfg->fc_dst, cfg->fc_dst_len,
1429 &cfg->fc_src, cfg->fc_src_len);
1430
1431 if (fn) {
1432 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1433 if (cfg->fc_ifindex &&
1434 (rt->rt6i_dev == NULL ||
1435 rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1436 continue;
1437 if (cfg->fc_flags & RTF_GATEWAY &&
1438 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1439 continue;
1440 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1441 continue;
1442 dst_hold(&rt->dst);
1443 read_unlock_bh(&table->tb6_lock);
1444
1445 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1446 }
1447 }
1448 read_unlock_bh(&table->tb6_lock);
1449
1450 return err;
1451 }
1452
1453 /*
1454 * Handle redirects
1455 */
1456 struct ip6rd_flowi {
1457 struct flowi6 fl6;
1458 struct in6_addr gateway;
1459 };
1460
1461 static struct rt6_info *__ip6_route_redirect(struct net *net,
1462 struct fib6_table *table,
1463 struct flowi6 *fl6,
1464 int flags)
1465 {
1466 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1467 struct rt6_info *rt;
1468 struct fib6_node *fn;
1469
1470 /*
1471 * Get the "current" route for this destination and
1472 * check if the redirect has come from approriate router.
1473 *
1474 * RFC 2461 specifies that redirects should only be
1475 * accepted if they come from the nexthop to the target.
1476 * Due to the way the routes are chosen, this notion
1477 * is a bit fuzzy and one might need to check all possible
1478 * routes.
1479 */
1480
1481 read_lock_bh(&table->tb6_lock);
1482 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1483 restart:
1484 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1485 /*
1486 * Current route is on-link; redirect is always invalid.
1487 *
1488 * Seems, previous statement is not true. It could
1489 * be node, which looks for us as on-link (f.e. proxy ndisc)
1490 * But then router serving it might decide, that we should
1491 * know truth 8)8) --ANK (980726).
1492 */
1493 if (rt6_check_expired(rt))
1494 continue;
1495 if (!(rt->rt6i_flags & RTF_GATEWAY))
1496 continue;
1497 if (fl6->flowi6_oif != rt->rt6i_dev->ifindex)
1498 continue;
1499 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1500 continue;
1501 break;
1502 }
1503
1504 if (!rt)
1505 rt = net->ipv6.ip6_null_entry;
1506 BACKTRACK(net, &fl6->saddr);
1507 out:
1508 dst_hold(&rt->dst);
1509
1510 read_unlock_bh(&table->tb6_lock);
1511
1512 return rt;
1513 };
1514
1515 static struct rt6_info *ip6_route_redirect(const struct in6_addr *dest,
1516 const struct in6_addr *src,
1517 const struct in6_addr *gateway,
1518 struct net_device *dev)
1519 {
1520 int flags = RT6_LOOKUP_F_HAS_SADDR;
1521 struct net *net = dev_net(dev);
1522 struct ip6rd_flowi rdfl = {
1523 .fl6 = {
1524 .flowi6_oif = dev->ifindex,
1525 .daddr = *dest,
1526 .saddr = *src,
1527 },
1528 };
1529
1530 ipv6_addr_copy(&rdfl.gateway, gateway);
1531
1532 if (rt6_need_strict(dest))
1533 flags |= RT6_LOOKUP_F_IFACE;
1534
1535 return (struct rt6_info *)fib6_rule_lookup(net, &rdfl.fl6,
1536 flags, __ip6_route_redirect);
1537 }
1538
1539 void rt6_redirect(const struct in6_addr *dest, const struct in6_addr *src,
1540 const struct in6_addr *saddr,
1541 struct neighbour *neigh, u8 *lladdr, int on_link)
1542 {
1543 struct rt6_info *rt, *nrt = NULL;
1544 struct netevent_redirect netevent;
1545 struct net *net = dev_net(neigh->dev);
1546
1547 rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1548
1549 if (rt == net->ipv6.ip6_null_entry) {
1550 if (net_ratelimit())
1551 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1552 "for redirect target\n");
1553 goto out;
1554 }
1555
1556 /*
1557 * We have finally decided to accept it.
1558 */
1559
1560 neigh_update(neigh, lladdr, NUD_STALE,
1561 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1562 NEIGH_UPDATE_F_OVERRIDE|
1563 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1564 NEIGH_UPDATE_F_ISROUTER))
1565 );
1566
1567 /*
1568 * Redirect received -> path was valid.
1569 * Look, redirects are sent only in response to data packets,
1570 * so that this nexthop apparently is reachable. --ANK
1571 */
1572 dst_confirm(&rt->dst);
1573
1574 /* Duplicate redirect: silently ignore. */
1575 if (neigh == rt->dst.neighbour)
1576 goto out;
1577
1578 nrt = ip6_rt_copy(rt);
1579 if (nrt == NULL)
1580 goto out;
1581
1582 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1583 if (on_link)
1584 nrt->rt6i_flags &= ~RTF_GATEWAY;
1585
1586 ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1587 nrt->rt6i_dst.plen = 128;
1588 nrt->dst.flags |= DST_HOST;
1589
1590 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1591 nrt->rt6i_nexthop = neigh_clone(neigh);
1592
1593 if (ip6_ins_rt(nrt))
1594 goto out;
1595
1596 netevent.old = &rt->dst;
1597 netevent.new = &nrt->dst;
1598 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1599
1600 if (rt->rt6i_flags&RTF_CACHE) {
1601 ip6_del_rt(rt);
1602 return;
1603 }
1604
1605 out:
1606 dst_release(&rt->dst);
1607 }
1608
1609 /*
1610 * Handle ICMP "packet too big" messages
1611 * i.e. Path MTU discovery
1612 */
1613
1614 static void rt6_do_pmtu_disc(const struct in6_addr *daddr, const struct in6_addr *saddr,
1615 struct net *net, u32 pmtu, int ifindex)
1616 {
1617 struct rt6_info *rt, *nrt;
1618 int allfrag = 0;
1619 again:
1620 rt = rt6_lookup(net, daddr, saddr, ifindex, 0);
1621 if (rt == NULL)
1622 return;
1623
1624 if (rt6_check_expired(rt)) {
1625 ip6_del_rt(rt);
1626 goto again;
1627 }
1628
1629 if (pmtu >= dst_mtu(&rt->dst))
1630 goto out;
1631
1632 if (pmtu < IPV6_MIN_MTU) {
1633 /*
1634 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1635 * MTU (1280) and a fragment header should always be included
1636 * after a node receiving Too Big message reporting PMTU is
1637 * less than the IPv6 Minimum Link MTU.
1638 */
1639 pmtu = IPV6_MIN_MTU;
1640 allfrag = 1;
1641 }
1642
1643 /* New mtu received -> path was valid.
1644 They are sent only in response to data packets,
1645 so that this nexthop apparently is reachable. --ANK
1646 */
1647 dst_confirm(&rt->dst);
1648
1649 /* Host route. If it is static, it would be better
1650 not to override it, but add new one, so that
1651 when cache entry will expire old pmtu
1652 would return automatically.
1653 */
1654 if (rt->rt6i_flags & RTF_CACHE) {
1655 dst_metric_set(&rt->dst, RTAX_MTU, pmtu);
1656 if (allfrag) {
1657 u32 features = dst_metric(&rt->dst, RTAX_FEATURES);
1658 features |= RTAX_FEATURE_ALLFRAG;
1659 dst_metric_set(&rt->dst, RTAX_FEATURES, features);
1660 }
1661 dst_set_expires(&rt->dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1662 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1663 goto out;
1664 }
1665
1666 /* Network route.
1667 Two cases are possible:
1668 1. It is connected route. Action: COW
1669 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1670 */
1671 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1672 nrt = rt6_alloc_cow(rt, daddr, saddr);
1673 else
1674 nrt = rt6_alloc_clone(rt, daddr);
1675
1676 if (nrt) {
1677 dst_metric_set(&nrt->dst, RTAX_MTU, pmtu);
1678 if (allfrag) {
1679 u32 features = dst_metric(&nrt->dst, RTAX_FEATURES);
1680 features |= RTAX_FEATURE_ALLFRAG;
1681 dst_metric_set(&nrt->dst, RTAX_FEATURES, features);
1682 }
1683
1684 /* According to RFC 1981, detecting PMTU increase shouldn't be
1685 * happened within 5 mins, the recommended timer is 10 mins.
1686 * Here this route expiration time is set to ip6_rt_mtu_expires
1687 * which is 10 mins. After 10 mins the decreased pmtu is expired
1688 * and detecting PMTU increase will be automatically happened.
1689 */
1690 dst_set_expires(&nrt->dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1691 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1692
1693 ip6_ins_rt(nrt);
1694 }
1695 out:
1696 dst_release(&rt->dst);
1697 }
1698
1699 void rt6_pmtu_discovery(const struct in6_addr *daddr, const struct in6_addr *saddr,
1700 struct net_device *dev, u32 pmtu)
1701 {
1702 struct net *net = dev_net(dev);
1703
1704 /*
1705 * RFC 1981 states that a node "MUST reduce the size of the packets it
1706 * is sending along the path" that caused the Packet Too Big message.
1707 * Since it's not possible in the general case to determine which
1708 * interface was used to send the original packet, we update the MTU
1709 * on the interface that will be used to send future packets. We also
1710 * update the MTU on the interface that received the Packet Too Big in
1711 * case the original packet was forced out that interface with
1712 * SO_BINDTODEVICE or similar. This is the next best thing to the
1713 * correct behaviour, which would be to update the MTU on all
1714 * interfaces.
1715 */
1716 rt6_do_pmtu_disc(daddr, saddr, net, pmtu, 0);
1717 rt6_do_pmtu_disc(daddr, saddr, net, pmtu, dev->ifindex);
1718 }
1719
1720 /*
1721 * Misc support functions
1722 */
1723
1724 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1725 {
1726 struct net *net = dev_net(ort->rt6i_dev);
1727 struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
1728
1729 if (rt) {
1730 rt->dst.input = ort->dst.input;
1731 rt->dst.output = ort->dst.output;
1732
1733 dst_copy_metrics(&rt->dst, &ort->dst);
1734 rt->dst.error = ort->dst.error;
1735 rt->dst.dev = ort->dst.dev;
1736 if (rt->dst.dev)
1737 dev_hold(rt->dst.dev);
1738 rt->rt6i_idev = ort->rt6i_idev;
1739 if (rt->rt6i_idev)
1740 in6_dev_hold(rt->rt6i_idev);
1741 rt->dst.lastuse = jiffies;
1742 rt->rt6i_expires = 0;
1743
1744 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1745 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1746 rt->rt6i_metric = 0;
1747
1748 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1749 #ifdef CONFIG_IPV6_SUBTREES
1750 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1751 #endif
1752 rt->rt6i_table = ort->rt6i_table;
1753 }
1754 return rt;
1755 }
1756
1757 #ifdef CONFIG_IPV6_ROUTE_INFO
1758 static struct rt6_info *rt6_get_route_info(struct net *net,
1759 const struct in6_addr *prefix, int prefixlen,
1760 const struct in6_addr *gwaddr, int ifindex)
1761 {
1762 struct fib6_node *fn;
1763 struct rt6_info *rt = NULL;
1764 struct fib6_table *table;
1765
1766 table = fib6_get_table(net, RT6_TABLE_INFO);
1767 if (table == NULL)
1768 return NULL;
1769
1770 write_lock_bh(&table->tb6_lock);
1771 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1772 if (!fn)
1773 goto out;
1774
1775 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1776 if (rt->rt6i_dev->ifindex != ifindex)
1777 continue;
1778 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1779 continue;
1780 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1781 continue;
1782 dst_hold(&rt->dst);
1783 break;
1784 }
1785 out:
1786 write_unlock_bh(&table->tb6_lock);
1787 return rt;
1788 }
1789
1790 static struct rt6_info *rt6_add_route_info(struct net *net,
1791 const struct in6_addr *prefix, int prefixlen,
1792 const struct in6_addr *gwaddr, int ifindex,
1793 unsigned pref)
1794 {
1795 struct fib6_config cfg = {
1796 .fc_table = RT6_TABLE_INFO,
1797 .fc_metric = IP6_RT_PRIO_USER,
1798 .fc_ifindex = ifindex,
1799 .fc_dst_len = prefixlen,
1800 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1801 RTF_UP | RTF_PREF(pref),
1802 .fc_nlinfo.pid = 0,
1803 .fc_nlinfo.nlh = NULL,
1804 .fc_nlinfo.nl_net = net,
1805 };
1806
1807 ipv6_addr_copy(&cfg.fc_dst, prefix);
1808 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1809
1810 /* We should treat it as a default route if prefix length is 0. */
1811 if (!prefixlen)
1812 cfg.fc_flags |= RTF_DEFAULT;
1813
1814 ip6_route_add(&cfg);
1815
1816 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
1817 }
1818 #endif
1819
1820 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
1821 {
1822 struct rt6_info *rt;
1823 struct fib6_table *table;
1824
1825 table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
1826 if (table == NULL)
1827 return NULL;
1828
1829 write_lock_bh(&table->tb6_lock);
1830 for (rt = table->tb6_root.leaf; rt; rt=rt->dst.rt6_next) {
1831 if (dev == rt->rt6i_dev &&
1832 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1833 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1834 break;
1835 }
1836 if (rt)
1837 dst_hold(&rt->dst);
1838 write_unlock_bh(&table->tb6_lock);
1839 return rt;
1840 }
1841
1842 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
1843 struct net_device *dev,
1844 unsigned int pref)
1845 {
1846 struct fib6_config cfg = {
1847 .fc_table = RT6_TABLE_DFLT,
1848 .fc_metric = IP6_RT_PRIO_USER,
1849 .fc_ifindex = dev->ifindex,
1850 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1851 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1852 .fc_nlinfo.pid = 0,
1853 .fc_nlinfo.nlh = NULL,
1854 .fc_nlinfo.nl_net = dev_net(dev),
1855 };
1856
1857 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1858
1859 ip6_route_add(&cfg);
1860
1861 return rt6_get_dflt_router(gwaddr, dev);
1862 }
1863
1864 void rt6_purge_dflt_routers(struct net *net)
1865 {
1866 struct rt6_info *rt;
1867 struct fib6_table *table;
1868
1869 /* NOTE: Keep consistent with rt6_get_dflt_router */
1870 table = fib6_get_table(net, RT6_TABLE_DFLT);
1871 if (table == NULL)
1872 return;
1873
1874 restart:
1875 read_lock_bh(&table->tb6_lock);
1876 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
1877 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1878 dst_hold(&rt->dst);
1879 read_unlock_bh(&table->tb6_lock);
1880 ip6_del_rt(rt);
1881 goto restart;
1882 }
1883 }
1884 read_unlock_bh(&table->tb6_lock);
1885 }
1886
1887 static void rtmsg_to_fib6_config(struct net *net,
1888 struct in6_rtmsg *rtmsg,
1889 struct fib6_config *cfg)
1890 {
1891 memset(cfg, 0, sizeof(*cfg));
1892
1893 cfg->fc_table = RT6_TABLE_MAIN;
1894 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1895 cfg->fc_metric = rtmsg->rtmsg_metric;
1896 cfg->fc_expires = rtmsg->rtmsg_info;
1897 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1898 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1899 cfg->fc_flags = rtmsg->rtmsg_flags;
1900
1901 cfg->fc_nlinfo.nl_net = net;
1902
1903 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1904 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1905 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1906 }
1907
1908 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
1909 {
1910 struct fib6_config cfg;
1911 struct in6_rtmsg rtmsg;
1912 int err;
1913
1914 switch(cmd) {
1915 case SIOCADDRT: /* Add a route */
1916 case SIOCDELRT: /* Delete a route */
1917 if (!capable(CAP_NET_ADMIN))
1918 return -EPERM;
1919 err = copy_from_user(&rtmsg, arg,
1920 sizeof(struct in6_rtmsg));
1921 if (err)
1922 return -EFAULT;
1923
1924 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
1925
1926 rtnl_lock();
1927 switch (cmd) {
1928 case SIOCADDRT:
1929 err = ip6_route_add(&cfg);
1930 break;
1931 case SIOCDELRT:
1932 err = ip6_route_del(&cfg);
1933 break;
1934 default:
1935 err = -EINVAL;
1936 }
1937 rtnl_unlock();
1938
1939 return err;
1940 }
1941
1942 return -EINVAL;
1943 }
1944
1945 /*
1946 * Drop the packet on the floor
1947 */
1948
1949 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
1950 {
1951 int type;
1952 struct dst_entry *dst = skb_dst(skb);
1953 switch (ipstats_mib_noroutes) {
1954 case IPSTATS_MIB_INNOROUTES:
1955 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
1956 if (type == IPV6_ADDR_ANY) {
1957 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
1958 IPSTATS_MIB_INADDRERRORS);
1959 break;
1960 }
1961 /* FALLTHROUGH */
1962 case IPSTATS_MIB_OUTNOROUTES:
1963 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
1964 ipstats_mib_noroutes);
1965 break;
1966 }
1967 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
1968 kfree_skb(skb);
1969 return 0;
1970 }
1971
1972 static int ip6_pkt_discard(struct sk_buff *skb)
1973 {
1974 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
1975 }
1976
1977 static int ip6_pkt_discard_out(struct sk_buff *skb)
1978 {
1979 skb->dev = skb_dst(skb)->dev;
1980 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
1981 }
1982
1983 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1984
1985 static int ip6_pkt_prohibit(struct sk_buff *skb)
1986 {
1987 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
1988 }
1989
1990 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
1991 {
1992 skb->dev = skb_dst(skb)->dev;
1993 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
1994 }
1995
1996 #endif
1997
1998 /*
1999 * Allocate a dst for local (unicast / anycast) address.
2000 */
2001
2002 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2003 const struct in6_addr *addr,
2004 int anycast)
2005 {
2006 struct net *net = dev_net(idev->dev);
2007 struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
2008 struct neighbour *neigh;
2009
2010 if (rt == NULL) {
2011 if (net_ratelimit())
2012 pr_warning("IPv6: Maximum number of routes reached,"
2013 " consider increasing route/max_size.\n");
2014 return ERR_PTR(-ENOMEM);
2015 }
2016
2017 dev_hold(net->loopback_dev);
2018 in6_dev_hold(idev);
2019
2020 rt->dst.flags = DST_HOST;
2021 rt->dst.input = ip6_input;
2022 rt->dst.output = ip6_output;
2023 rt->rt6i_dev = net->loopback_dev;
2024 rt->rt6i_idev = idev;
2025 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, -1);
2026 rt->dst.obsolete = -1;
2027
2028 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2029 if (anycast)
2030 rt->rt6i_flags |= RTF_ANYCAST;
2031 else
2032 rt->rt6i_flags |= RTF_LOCAL;
2033 neigh = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
2034 if (IS_ERR(neigh)) {
2035 dst_free(&rt->dst);
2036
2037 return ERR_CAST(neigh);
2038 }
2039 rt->rt6i_nexthop = neigh;
2040
2041 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
2042 rt->rt6i_dst.plen = 128;
2043 rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2044
2045 atomic_set(&rt->dst.__refcnt, 1);
2046
2047 return rt;
2048 }
2049
2050 int ip6_route_get_saddr(struct net *net,
2051 struct rt6_info *rt,
2052 const struct in6_addr *daddr,
2053 unsigned int prefs,
2054 struct in6_addr *saddr)
2055 {
2056 struct inet6_dev *idev = ip6_dst_idev((struct dst_entry*)rt);
2057 int err = 0;
2058 if (rt->rt6i_prefsrc.plen)
2059 ipv6_addr_copy(saddr, &rt->rt6i_prefsrc.addr);
2060 else
2061 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2062 daddr, prefs, saddr);
2063 return err;
2064 }
2065
2066 /* remove deleted ip from prefsrc entries */
2067 struct arg_dev_net_ip {
2068 struct net_device *dev;
2069 struct net *net;
2070 struct in6_addr *addr;
2071 };
2072
2073 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2074 {
2075 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2076 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2077 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2078
2079 if (((void *)rt->rt6i_dev == dev || dev == NULL) &&
2080 rt != net->ipv6.ip6_null_entry &&
2081 ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2082 /* remove prefsrc entry */
2083 rt->rt6i_prefsrc.plen = 0;
2084 }
2085 return 0;
2086 }
2087
2088 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2089 {
2090 struct net *net = dev_net(ifp->idev->dev);
2091 struct arg_dev_net_ip adni = {
2092 .dev = ifp->idev->dev,
2093 .net = net,
2094 .addr = &ifp->addr,
2095 };
2096 fib6_clean_all(net, fib6_remove_prefsrc, 0, &adni);
2097 }
2098
2099 struct arg_dev_net {
2100 struct net_device *dev;
2101 struct net *net;
2102 };
2103
2104 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2105 {
2106 const struct arg_dev_net *adn = arg;
2107 const struct net_device *dev = adn->dev;
2108
2109 if ((rt->rt6i_dev == dev || dev == NULL) &&
2110 rt != adn->net->ipv6.ip6_null_entry) {
2111 RT6_TRACE("deleted by ifdown %p\n", rt);
2112 return -1;
2113 }
2114 return 0;
2115 }
2116
2117 void rt6_ifdown(struct net *net, struct net_device *dev)
2118 {
2119 struct arg_dev_net adn = {
2120 .dev = dev,
2121 .net = net,
2122 };
2123
2124 fib6_clean_all(net, fib6_ifdown, 0, &adn);
2125 icmp6_clean_all(fib6_ifdown, &adn);
2126 }
2127
2128 struct rt6_mtu_change_arg
2129 {
2130 struct net_device *dev;
2131 unsigned mtu;
2132 };
2133
2134 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2135 {
2136 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2137 struct inet6_dev *idev;
2138
2139 /* In IPv6 pmtu discovery is not optional,
2140 so that RTAX_MTU lock cannot disable it.
2141 We still use this lock to block changes
2142 caused by addrconf/ndisc.
2143 */
2144
2145 idev = __in6_dev_get(arg->dev);
2146 if (idev == NULL)
2147 return 0;
2148
2149 /* For administrative MTU increase, there is no way to discover
2150 IPv6 PMTU increase, so PMTU increase should be updated here.
2151 Since RFC 1981 doesn't include administrative MTU increase
2152 update PMTU increase is a MUST. (i.e. jumbo frame)
2153 */
2154 /*
2155 If new MTU is less than route PMTU, this new MTU will be the
2156 lowest MTU in the path, update the route PMTU to reflect PMTU
2157 decreases; if new MTU is greater than route PMTU, and the
2158 old MTU is the lowest MTU in the path, update the route PMTU
2159 to reflect the increase. In this case if the other nodes' MTU
2160 also have the lowest MTU, TOO BIG MESSAGE will be lead to
2161 PMTU discouvery.
2162 */
2163 if (rt->rt6i_dev == arg->dev &&
2164 !dst_metric_locked(&rt->dst, RTAX_MTU) &&
2165 (dst_mtu(&rt->dst) >= arg->mtu ||
2166 (dst_mtu(&rt->dst) < arg->mtu &&
2167 dst_mtu(&rt->dst) == idev->cnf.mtu6))) {
2168 dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2169 }
2170 return 0;
2171 }
2172
2173 void rt6_mtu_change(struct net_device *dev, unsigned mtu)
2174 {
2175 struct rt6_mtu_change_arg arg = {
2176 .dev = dev,
2177 .mtu = mtu,
2178 };
2179
2180 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg);
2181 }
2182
2183 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2184 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
2185 [RTA_OIF] = { .type = NLA_U32 },
2186 [RTA_IIF] = { .type = NLA_U32 },
2187 [RTA_PRIORITY] = { .type = NLA_U32 },
2188 [RTA_METRICS] = { .type = NLA_NESTED },
2189 };
2190
2191 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2192 struct fib6_config *cfg)
2193 {
2194 struct rtmsg *rtm;
2195 struct nlattr *tb[RTA_MAX+1];
2196 int err;
2197
2198 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2199 if (err < 0)
2200 goto errout;
2201
2202 err = -EINVAL;
2203 rtm = nlmsg_data(nlh);
2204 memset(cfg, 0, sizeof(*cfg));
2205
2206 cfg->fc_table = rtm->rtm_table;
2207 cfg->fc_dst_len = rtm->rtm_dst_len;
2208 cfg->fc_src_len = rtm->rtm_src_len;
2209 cfg->fc_flags = RTF_UP;
2210 cfg->fc_protocol = rtm->rtm_protocol;
2211
2212 if (rtm->rtm_type == RTN_UNREACHABLE)
2213 cfg->fc_flags |= RTF_REJECT;
2214
2215 if (rtm->rtm_type == RTN_LOCAL)
2216 cfg->fc_flags |= RTF_LOCAL;
2217
2218 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
2219 cfg->fc_nlinfo.nlh = nlh;
2220 cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2221
2222 if (tb[RTA_GATEWAY]) {
2223 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
2224 cfg->fc_flags |= RTF_GATEWAY;
2225 }
2226
2227 if (tb[RTA_DST]) {
2228 int plen = (rtm->rtm_dst_len + 7) >> 3;
2229
2230 if (nla_len(tb[RTA_DST]) < plen)
2231 goto errout;
2232
2233 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2234 }
2235
2236 if (tb[RTA_SRC]) {
2237 int plen = (rtm->rtm_src_len + 7) >> 3;
2238
2239 if (nla_len(tb[RTA_SRC]) < plen)
2240 goto errout;
2241
2242 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2243 }
2244
2245 if (tb[RTA_PREFSRC])
2246 nla_memcpy(&cfg->fc_prefsrc, tb[RTA_PREFSRC], 16);
2247
2248 if (tb[RTA_OIF])
2249 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2250
2251 if (tb[RTA_PRIORITY])
2252 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2253
2254 if (tb[RTA_METRICS]) {
2255 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2256 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2257 }
2258
2259 if (tb[RTA_TABLE])
2260 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2261
2262 err = 0;
2263 errout:
2264 return err;
2265 }
2266
2267 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2268 {
2269 struct fib6_config cfg;
2270 int err;
2271
2272 err = rtm_to_fib6_config(skb, nlh, &cfg);
2273 if (err < 0)
2274 return err;
2275
2276 return ip6_route_del(&cfg);
2277 }
2278
2279 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2280 {
2281 struct fib6_config cfg;
2282 int err;
2283
2284 err = rtm_to_fib6_config(skb, nlh, &cfg);
2285 if (err < 0)
2286 return err;
2287
2288 return ip6_route_add(&cfg);
2289 }
2290
2291 static inline size_t rt6_nlmsg_size(void)
2292 {
2293 return NLMSG_ALIGN(sizeof(struct rtmsg))
2294 + nla_total_size(16) /* RTA_SRC */
2295 + nla_total_size(16) /* RTA_DST */
2296 + nla_total_size(16) /* RTA_GATEWAY */
2297 + nla_total_size(16) /* RTA_PREFSRC */
2298 + nla_total_size(4) /* RTA_TABLE */
2299 + nla_total_size(4) /* RTA_IIF */
2300 + nla_total_size(4) /* RTA_OIF */
2301 + nla_total_size(4) /* RTA_PRIORITY */
2302 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2303 + nla_total_size(sizeof(struct rta_cacheinfo));
2304 }
2305
2306 static int rt6_fill_node(struct net *net,
2307 struct sk_buff *skb, struct rt6_info *rt,
2308 struct in6_addr *dst, struct in6_addr *src,
2309 int iif, int type, u32 pid, u32 seq,
2310 int prefix, int nowait, unsigned int flags)
2311 {
2312 struct rtmsg *rtm;
2313 struct nlmsghdr *nlh;
2314 long expires;
2315 u32 table;
2316
2317 if (prefix) { /* user wants prefix routes only */
2318 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2319 /* success since this is not a prefix route */
2320 return 1;
2321 }
2322 }
2323
2324 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2325 if (nlh == NULL)
2326 return -EMSGSIZE;
2327
2328 rtm = nlmsg_data(nlh);
2329 rtm->rtm_family = AF_INET6;
2330 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2331 rtm->rtm_src_len = rt->rt6i_src.plen;
2332 rtm->rtm_tos = 0;
2333 if (rt->rt6i_table)
2334 table = rt->rt6i_table->tb6_id;
2335 else
2336 table = RT6_TABLE_UNSPEC;
2337 rtm->rtm_table = table;
2338 NLA_PUT_U32(skb, RTA_TABLE, table);
2339 if (rt->rt6i_flags&RTF_REJECT)
2340 rtm->rtm_type = RTN_UNREACHABLE;
2341 else if (rt->rt6i_flags&RTF_LOCAL)
2342 rtm->rtm_type = RTN_LOCAL;
2343 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2344 rtm->rtm_type = RTN_LOCAL;
2345 else
2346 rtm->rtm_type = RTN_UNICAST;
2347 rtm->rtm_flags = 0;
2348 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2349 rtm->rtm_protocol = rt->rt6i_protocol;
2350 if (rt->rt6i_flags&RTF_DYNAMIC)
2351 rtm->rtm_protocol = RTPROT_REDIRECT;
2352 else if (rt->rt6i_flags & RTF_ADDRCONF)
2353 rtm->rtm_protocol = RTPROT_KERNEL;
2354 else if (rt->rt6i_flags&RTF_DEFAULT)
2355 rtm->rtm_protocol = RTPROT_RA;
2356
2357 if (rt->rt6i_flags&RTF_CACHE)
2358 rtm->rtm_flags |= RTM_F_CLONED;
2359
2360 if (dst) {
2361 NLA_PUT(skb, RTA_DST, 16, dst);
2362 rtm->rtm_dst_len = 128;
2363 } else if (rtm->rtm_dst_len)
2364 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2365 #ifdef CONFIG_IPV6_SUBTREES
2366 if (src) {
2367 NLA_PUT(skb, RTA_SRC, 16, src);
2368 rtm->rtm_src_len = 128;
2369 } else if (rtm->rtm_src_len)
2370 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2371 #endif
2372 if (iif) {
2373 #ifdef CONFIG_IPV6_MROUTE
2374 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2375 int err = ip6mr_get_route(net, skb, rtm, nowait);
2376 if (err <= 0) {
2377 if (!nowait) {
2378 if (err == 0)
2379 return 0;
2380 goto nla_put_failure;
2381 } else {
2382 if (err == -EMSGSIZE)
2383 goto nla_put_failure;
2384 }
2385 }
2386 } else
2387 #endif
2388 NLA_PUT_U32(skb, RTA_IIF, iif);
2389 } else if (dst) {
2390 struct in6_addr saddr_buf;
2391 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0)
2392 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2393 }
2394
2395 if (rt->rt6i_prefsrc.plen) {
2396 struct in6_addr saddr_buf;
2397 ipv6_addr_copy(&saddr_buf, &rt->rt6i_prefsrc.addr);
2398 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2399 }
2400
2401 if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
2402 goto nla_put_failure;
2403
2404 if (rt->dst.neighbour)
2405 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->dst.neighbour->primary_key);
2406
2407 if (rt->dst.dev)
2408 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2409
2410 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2411
2412 if (!(rt->rt6i_flags & RTF_EXPIRES))
2413 expires = 0;
2414 else if (rt->rt6i_expires - jiffies < INT_MAX)
2415 expires = rt->rt6i_expires - jiffies;
2416 else
2417 expires = INT_MAX;
2418
2419 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, 0, 0,
2420 expires, rt->dst.error) < 0)
2421 goto nla_put_failure;
2422
2423 return nlmsg_end(skb, nlh);
2424
2425 nla_put_failure:
2426 nlmsg_cancel(skb, nlh);
2427 return -EMSGSIZE;
2428 }
2429
2430 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2431 {
2432 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2433 int prefix;
2434
2435 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2436 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2437 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2438 } else
2439 prefix = 0;
2440
2441 return rt6_fill_node(arg->net,
2442 arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2443 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2444 prefix, 0, NLM_F_MULTI);
2445 }
2446
2447 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2448 {
2449 struct net *net = sock_net(in_skb->sk);
2450 struct nlattr *tb[RTA_MAX+1];
2451 struct rt6_info *rt;
2452 struct sk_buff *skb;
2453 struct rtmsg *rtm;
2454 struct flowi6 fl6;
2455 int err, iif = 0;
2456
2457 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2458 if (err < 0)
2459 goto errout;
2460
2461 err = -EINVAL;
2462 memset(&fl6, 0, sizeof(fl6));
2463
2464 if (tb[RTA_SRC]) {
2465 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2466 goto errout;
2467
2468 ipv6_addr_copy(&fl6.saddr, nla_data(tb[RTA_SRC]));
2469 }
2470
2471 if (tb[RTA_DST]) {
2472 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2473 goto errout;
2474
2475 ipv6_addr_copy(&fl6.daddr, nla_data(tb[RTA_DST]));
2476 }
2477
2478 if (tb[RTA_IIF])
2479 iif = nla_get_u32(tb[RTA_IIF]);
2480
2481 if (tb[RTA_OIF])
2482 fl6.flowi6_oif = nla_get_u32(tb[RTA_OIF]);
2483
2484 if (iif) {
2485 struct net_device *dev;
2486 dev = __dev_get_by_index(net, iif);
2487 if (!dev) {
2488 err = -ENODEV;
2489 goto errout;
2490 }
2491 }
2492
2493 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2494 if (skb == NULL) {
2495 err = -ENOBUFS;
2496 goto errout;
2497 }
2498
2499 /* Reserve room for dummy headers, this skb can pass
2500 through good chunk of routing engine.
2501 */
2502 skb_reset_mac_header(skb);
2503 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2504
2505 rt = (struct rt6_info*) ip6_route_output(net, NULL, &fl6);
2506 skb_dst_set(skb, &rt->dst);
2507
2508 err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
2509 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2510 nlh->nlmsg_seq, 0, 0, 0);
2511 if (err < 0) {
2512 kfree_skb(skb);
2513 goto errout;
2514 }
2515
2516 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2517 errout:
2518 return err;
2519 }
2520
2521 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2522 {
2523 struct sk_buff *skb;
2524 struct net *net = info->nl_net;
2525 u32 seq;
2526 int err;
2527
2528 err = -ENOBUFS;
2529 seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0;
2530
2531 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2532 if (skb == NULL)
2533 goto errout;
2534
2535 err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
2536 event, info->pid, seq, 0, 0, 0);
2537 if (err < 0) {
2538 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2539 WARN_ON(err == -EMSGSIZE);
2540 kfree_skb(skb);
2541 goto errout;
2542 }
2543 rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE,
2544 info->nlh, gfp_any());
2545 return;
2546 errout:
2547 if (err < 0)
2548 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
2549 }
2550
2551 static int ip6_route_dev_notify(struct notifier_block *this,
2552 unsigned long event, void *data)
2553 {
2554 struct net_device *dev = (struct net_device *)data;
2555 struct net *net = dev_net(dev);
2556
2557 if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
2558 net->ipv6.ip6_null_entry->dst.dev = dev;
2559 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
2560 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2561 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
2562 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
2563 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
2564 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
2565 #endif
2566 }
2567
2568 return NOTIFY_OK;
2569 }
2570
2571 /*
2572 * /proc
2573 */
2574
2575 #ifdef CONFIG_PROC_FS
2576
2577 struct rt6_proc_arg
2578 {
2579 char *buffer;
2580 int offset;
2581 int length;
2582 int skip;
2583 int len;
2584 };
2585
2586 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2587 {
2588 struct seq_file *m = p_arg;
2589
2590 seq_printf(m, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
2591
2592 #ifdef CONFIG_IPV6_SUBTREES
2593 seq_printf(m, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
2594 #else
2595 seq_puts(m, "00000000000000000000000000000000 00 ");
2596 #endif
2597
2598 if (rt->rt6i_nexthop) {
2599 seq_printf(m, "%pi6", rt->rt6i_nexthop->primary_key);
2600 } else {
2601 seq_puts(m, "00000000000000000000000000000000");
2602 }
2603 seq_printf(m, " %08x %08x %08x %08x %8s\n",
2604 rt->rt6i_metric, atomic_read(&rt->dst.__refcnt),
2605 rt->dst.__use, rt->rt6i_flags,
2606 rt->rt6i_dev ? rt->rt6i_dev->name : "");
2607 return 0;
2608 }
2609
2610 static int ipv6_route_show(struct seq_file *m, void *v)
2611 {
2612 struct net *net = (struct net *)m->private;
2613 fib6_clean_all(net, rt6_info_route, 0, m);
2614 return 0;
2615 }
2616
2617 static int ipv6_route_open(struct inode *inode, struct file *file)
2618 {
2619 return single_open_net(inode, file, ipv6_route_show);
2620 }
2621
2622 static const struct file_operations ipv6_route_proc_fops = {
2623 .owner = THIS_MODULE,
2624 .open = ipv6_route_open,
2625 .read = seq_read,
2626 .llseek = seq_lseek,
2627 .release = single_release_net,
2628 };
2629
2630 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2631 {
2632 struct net *net = (struct net *)seq->private;
2633 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2634 net->ipv6.rt6_stats->fib_nodes,
2635 net->ipv6.rt6_stats->fib_route_nodes,
2636 net->ipv6.rt6_stats->fib_rt_alloc,
2637 net->ipv6.rt6_stats->fib_rt_entries,
2638 net->ipv6.rt6_stats->fib_rt_cache,
2639 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
2640 net->ipv6.rt6_stats->fib_discarded_routes);
2641
2642 return 0;
2643 }
2644
2645 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2646 {
2647 return single_open_net(inode, file, rt6_stats_seq_show);
2648 }
2649
2650 static const struct file_operations rt6_stats_seq_fops = {
2651 .owner = THIS_MODULE,
2652 .open = rt6_stats_seq_open,
2653 .read = seq_read,
2654 .llseek = seq_lseek,
2655 .release = single_release_net,
2656 };
2657 #endif /* CONFIG_PROC_FS */
2658
2659 #ifdef CONFIG_SYSCTL
2660
2661 static
2662 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write,
2663 void __user *buffer, size_t *lenp, loff_t *ppos)
2664 {
2665 struct net *net;
2666 int delay;
2667 if (!write)
2668 return -EINVAL;
2669
2670 net = (struct net *)ctl->extra1;
2671 delay = net->ipv6.sysctl.flush_delay;
2672 proc_dointvec(ctl, write, buffer, lenp, ppos);
2673 fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net);
2674 return 0;
2675 }
2676
2677 ctl_table ipv6_route_table_template[] = {
2678 {
2679 .procname = "flush",
2680 .data = &init_net.ipv6.sysctl.flush_delay,
2681 .maxlen = sizeof(int),
2682 .mode = 0200,
2683 .proc_handler = ipv6_sysctl_rtcache_flush
2684 },
2685 {
2686 .procname = "gc_thresh",
2687 .data = &ip6_dst_ops_template.gc_thresh,
2688 .maxlen = sizeof(int),
2689 .mode = 0644,
2690 .proc_handler = proc_dointvec,
2691 },
2692 {
2693 .procname = "max_size",
2694 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
2695 .maxlen = sizeof(int),
2696 .mode = 0644,
2697 .proc_handler = proc_dointvec,
2698 },
2699 {
2700 .procname = "gc_min_interval",
2701 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2702 .maxlen = sizeof(int),
2703 .mode = 0644,
2704 .proc_handler = proc_dointvec_jiffies,
2705 },
2706 {
2707 .procname = "gc_timeout",
2708 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
2709 .maxlen = sizeof(int),
2710 .mode = 0644,
2711 .proc_handler = proc_dointvec_jiffies,
2712 },
2713 {
2714 .procname = "gc_interval",
2715 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
2716 .maxlen = sizeof(int),
2717 .mode = 0644,
2718 .proc_handler = proc_dointvec_jiffies,
2719 },
2720 {
2721 .procname = "gc_elasticity",
2722 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
2723 .maxlen = sizeof(int),
2724 .mode = 0644,
2725 .proc_handler = proc_dointvec,
2726 },
2727 {
2728 .procname = "mtu_expires",
2729 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
2730 .maxlen = sizeof(int),
2731 .mode = 0644,
2732 .proc_handler = proc_dointvec_jiffies,
2733 },
2734 {
2735 .procname = "min_adv_mss",
2736 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
2737 .maxlen = sizeof(int),
2738 .mode = 0644,
2739 .proc_handler = proc_dointvec,
2740 },
2741 {
2742 .procname = "gc_min_interval_ms",
2743 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2744 .maxlen = sizeof(int),
2745 .mode = 0644,
2746 .proc_handler = proc_dointvec_ms_jiffies,
2747 },
2748 { }
2749 };
2750
2751 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
2752 {
2753 struct ctl_table *table;
2754
2755 table = kmemdup(ipv6_route_table_template,
2756 sizeof(ipv6_route_table_template),
2757 GFP_KERNEL);
2758
2759 if (table) {
2760 table[0].data = &net->ipv6.sysctl.flush_delay;
2761 table[0].extra1 = net;
2762 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
2763 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
2764 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2765 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
2766 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
2767 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
2768 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
2769 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
2770 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2771 }
2772
2773 return table;
2774 }
2775 #endif
2776
2777 static int __net_init ip6_route_net_init(struct net *net)
2778 {
2779 int ret = -ENOMEM;
2780
2781 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
2782 sizeof(net->ipv6.ip6_dst_ops));
2783
2784 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
2785 goto out_ip6_dst_ops;
2786
2787 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
2788 sizeof(*net->ipv6.ip6_null_entry),
2789 GFP_KERNEL);
2790 if (!net->ipv6.ip6_null_entry)
2791 goto out_ip6_dst_entries;
2792 net->ipv6.ip6_null_entry->dst.path =
2793 (struct dst_entry *)net->ipv6.ip6_null_entry;
2794 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2795 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
2796 ip6_template_metrics, true);
2797
2798 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2799 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
2800 sizeof(*net->ipv6.ip6_prohibit_entry),
2801 GFP_KERNEL);
2802 if (!net->ipv6.ip6_prohibit_entry)
2803 goto out_ip6_null_entry;
2804 net->ipv6.ip6_prohibit_entry->dst.path =
2805 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
2806 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2807 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
2808 ip6_template_metrics, true);
2809
2810 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
2811 sizeof(*net->ipv6.ip6_blk_hole_entry),
2812 GFP_KERNEL);
2813 if (!net->ipv6.ip6_blk_hole_entry)
2814 goto out_ip6_prohibit_entry;
2815 net->ipv6.ip6_blk_hole_entry->dst.path =
2816 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
2817 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2818 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
2819 ip6_template_metrics, true);
2820 #endif
2821
2822 net->ipv6.sysctl.flush_delay = 0;
2823 net->ipv6.sysctl.ip6_rt_max_size = 4096;
2824 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
2825 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
2826 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
2827 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
2828 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
2829 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
2830
2831 #ifdef CONFIG_PROC_FS
2832 proc_net_fops_create(net, "ipv6_route", 0, &ipv6_route_proc_fops);
2833 proc_net_fops_create(net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2834 #endif
2835 net->ipv6.ip6_rt_gc_expire = 30*HZ;
2836
2837 ret = 0;
2838 out:
2839 return ret;
2840
2841 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2842 out_ip6_prohibit_entry:
2843 kfree(net->ipv6.ip6_prohibit_entry);
2844 out_ip6_null_entry:
2845 kfree(net->ipv6.ip6_null_entry);
2846 #endif
2847 out_ip6_dst_entries:
2848 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2849 out_ip6_dst_ops:
2850 goto out;
2851 }
2852
2853 static void __net_exit ip6_route_net_exit(struct net *net)
2854 {
2855 #ifdef CONFIG_PROC_FS
2856 proc_net_remove(net, "ipv6_route");
2857 proc_net_remove(net, "rt6_stats");
2858 #endif
2859 kfree(net->ipv6.ip6_null_entry);
2860 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2861 kfree(net->ipv6.ip6_prohibit_entry);
2862 kfree(net->ipv6.ip6_blk_hole_entry);
2863 #endif
2864 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2865 }
2866
2867 static struct pernet_operations ip6_route_net_ops = {
2868 .init = ip6_route_net_init,
2869 .exit = ip6_route_net_exit,
2870 };
2871
2872 static struct notifier_block ip6_route_dev_notifier = {
2873 .notifier_call = ip6_route_dev_notify,
2874 .priority = 0,
2875 };
2876
2877 int __init ip6_route_init(void)
2878 {
2879 int ret;
2880
2881 ret = -ENOMEM;
2882 ip6_dst_ops_template.kmem_cachep =
2883 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2884 SLAB_HWCACHE_ALIGN, NULL);
2885 if (!ip6_dst_ops_template.kmem_cachep)
2886 goto out;
2887
2888 ret = dst_entries_init(&ip6_dst_blackhole_ops);
2889 if (ret)
2890 goto out_kmem_cache;
2891
2892 ret = register_pernet_subsys(&ip6_route_net_ops);
2893 if (ret)
2894 goto out_dst_entries;
2895
2896 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
2897
2898 /* Registering of the loopback is done before this portion of code,
2899 * the loopback reference in rt6_info will not be taken, do it
2900 * manually for init_net */
2901 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
2902 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2903 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2904 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
2905 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2906 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
2907 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2908 #endif
2909 ret = fib6_init();
2910 if (ret)
2911 goto out_register_subsys;
2912
2913 ret = xfrm6_init();
2914 if (ret)
2915 goto out_fib6_init;
2916
2917 ret = fib6_rules_init();
2918 if (ret)
2919 goto xfrm6_init;
2920
2921 ret = -ENOBUFS;
2922 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) ||
2923 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) ||
2924 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL))
2925 goto fib6_rules_init;
2926
2927 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
2928 if (ret)
2929 goto fib6_rules_init;
2930
2931 out:
2932 return ret;
2933
2934 fib6_rules_init:
2935 fib6_rules_cleanup();
2936 xfrm6_init:
2937 xfrm6_fini();
2938 out_fib6_init:
2939 fib6_gc_cleanup();
2940 out_register_subsys:
2941 unregister_pernet_subsys(&ip6_route_net_ops);
2942 out_dst_entries:
2943 dst_entries_destroy(&ip6_dst_blackhole_ops);
2944 out_kmem_cache:
2945 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
2946 goto out;
2947 }
2948
2949 void ip6_route_cleanup(void)
2950 {
2951 unregister_netdevice_notifier(&ip6_route_dev_notifier);
2952 fib6_rules_cleanup();
2953 xfrm6_fini();
2954 fib6_gc_cleanup();
2955 unregister_pernet_subsys(&ip6_route_net_ops);
2956 dst_entries_destroy(&ip6_dst_blackhole_ops);
2957 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
2958 }
kernel-based virtual machine