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x86: Move call to print_modules() out of show_regs()
[deliverable/linux.git] / net / ipv6 / route.c
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 #define pr_fmt(fmt) "IPv6: " fmt
28
29 #include <linux/capability.h>
30 #include <linux/errno.h>
31 #include <linux/export.h>
32 #include <linux/types.h>
33 #include <linux/times.h>
34 #include <linux/socket.h>
35 #include <linux/sockios.h>
36 #include <linux/net.h>
37 #include <linux/route.h>
38 #include <linux/netdevice.h>
39 #include <linux/in6.h>
40 #include <linux/mroute6.h>
41 #include <linux/init.h>
42 #include <linux/if_arp.h>
43 #include <linux/proc_fs.h>
44 #include <linux/seq_file.h>
45 #include <linux/nsproxy.h>
46 #include <linux/slab.h>
47 #include <net/net_namespace.h>
48 #include <net/snmp.h>
49 #include <net/ipv6.h>
50 #include <net/ip6_fib.h>
51 #include <net/ip6_route.h>
52 #include <net/ndisc.h>
53 #include <net/addrconf.h>
54 #include <net/tcp.h>
55 #include <linux/rtnetlink.h>
56 #include <net/dst.h>
57 #include <net/xfrm.h>
58 #include <net/netevent.h>
59 #include <net/netlink.h>
60
61 #include <asm/uaccess.h>
62
63 #ifdef CONFIG_SYSCTL
64 #include <linux/sysctl.h>
65 #endif
66
67 static struct rt6_info *ip6_rt_copy(struct rt6_info *ort,
68 const struct in6_addr *dest);
69 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
70 static unsigned int ip6_default_advmss(const struct dst_entry *dst);
71 static unsigned int ip6_mtu(const struct dst_entry *dst);
72 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
73 static void ip6_dst_destroy(struct dst_entry *);
74 static void ip6_dst_ifdown(struct dst_entry *,
75 struct net_device *dev, int how);
76 static int ip6_dst_gc(struct dst_ops *ops);
77
78 static int ip6_pkt_discard(struct sk_buff *skb);
79 static int ip6_pkt_discard_out(struct sk_buff *skb);
80 static void ip6_link_failure(struct sk_buff *skb);
81 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
82
83 #ifdef CONFIG_IPV6_ROUTE_INFO
84 static struct rt6_info *rt6_add_route_info(struct net *net,
85 const struct in6_addr *prefix, int prefixlen,
86 const struct in6_addr *gwaddr, int ifindex,
87 unsigned int pref);
88 static struct rt6_info *rt6_get_route_info(struct net *net,
89 const struct in6_addr *prefix, int prefixlen,
90 const struct in6_addr *gwaddr, int ifindex);
91 #endif
92
93 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
94 {
95 struct rt6_info *rt = (struct rt6_info *) dst;
96 struct inet_peer *peer;
97 u32 *p = NULL;
98
99 if (!(rt->dst.flags & DST_HOST))
100 return NULL;
101
102 if (!rt->rt6i_peer)
103 rt6_bind_peer(rt, 1);
104
105 peer = rt->rt6i_peer;
106 if (peer) {
107 u32 *old_p = __DST_METRICS_PTR(old);
108 unsigned long prev, new;
109
110 p = peer->metrics;
111 if (inet_metrics_new(peer))
112 memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
113
114 new = (unsigned long) p;
115 prev = cmpxchg(&dst->_metrics, old, new);
116
117 if (prev != old) {
118 p = __DST_METRICS_PTR(prev);
119 if (prev & DST_METRICS_READ_ONLY)
120 p = NULL;
121 }
122 }
123 return p;
124 }
125
126 static inline const void *choose_neigh_daddr(struct rt6_info *rt, const void *daddr)
127 {
128 struct in6_addr *p = &rt->rt6i_gateway;
129
130 if (!ipv6_addr_any(p))
131 return (const void *) p;
132 return daddr;
133 }
134
135 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst, const void *daddr)
136 {
137 struct rt6_info *rt = (struct rt6_info *) dst;
138 struct neighbour *n;
139
140 daddr = choose_neigh_daddr(rt, daddr);
141 n = __ipv6_neigh_lookup(&nd_tbl, dst->dev, daddr);
142 if (n)
143 return n;
144 return neigh_create(&nd_tbl, daddr, dst->dev);
145 }
146
147 static int rt6_bind_neighbour(struct rt6_info *rt, struct net_device *dev)
148 {
149 struct neighbour *n = __ipv6_neigh_lookup(&nd_tbl, dev, &rt->rt6i_gateway);
150 if (!n) {
151 n = neigh_create(&nd_tbl, &rt->rt6i_gateway, dev);
152 if (IS_ERR(n))
153 return PTR_ERR(n);
154 }
155 dst_set_neighbour(&rt->dst, n);
156
157 return 0;
158 }
159
160 static struct dst_ops ip6_dst_ops_template = {
161 .family = AF_INET6,
162 .protocol = cpu_to_be16(ETH_P_IPV6),
163 .gc = ip6_dst_gc,
164 .gc_thresh = 1024,
165 .check = ip6_dst_check,
166 .default_advmss = ip6_default_advmss,
167 .mtu = ip6_mtu,
168 .cow_metrics = ipv6_cow_metrics,
169 .destroy = ip6_dst_destroy,
170 .ifdown = ip6_dst_ifdown,
171 .negative_advice = ip6_negative_advice,
172 .link_failure = ip6_link_failure,
173 .update_pmtu = ip6_rt_update_pmtu,
174 .local_out = __ip6_local_out,
175 .neigh_lookup = ip6_neigh_lookup,
176 };
177
178 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
179 {
180 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
181
182 return mtu ? : dst->dev->mtu;
183 }
184
185 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
186 {
187 }
188
189 static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
190 unsigned long old)
191 {
192 return NULL;
193 }
194
195 static struct dst_ops ip6_dst_blackhole_ops = {
196 .family = AF_INET6,
197 .protocol = cpu_to_be16(ETH_P_IPV6),
198 .destroy = ip6_dst_destroy,
199 .check = ip6_dst_check,
200 .mtu = ip6_blackhole_mtu,
201 .default_advmss = ip6_default_advmss,
202 .update_pmtu = ip6_rt_blackhole_update_pmtu,
203 .cow_metrics = ip6_rt_blackhole_cow_metrics,
204 .neigh_lookup = ip6_neigh_lookup,
205 };
206
207 static const u32 ip6_template_metrics[RTAX_MAX] = {
208 [RTAX_HOPLIMIT - 1] = 255,
209 };
210
211 static struct rt6_info ip6_null_entry_template = {
212 .dst = {
213 .__refcnt = ATOMIC_INIT(1),
214 .__use = 1,
215 .obsolete = -1,
216 .error = -ENETUNREACH,
217 .input = ip6_pkt_discard,
218 .output = ip6_pkt_discard_out,
219 },
220 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
221 .rt6i_protocol = RTPROT_KERNEL,
222 .rt6i_metric = ~(u32) 0,
223 .rt6i_ref = ATOMIC_INIT(1),
224 };
225
226 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
227
228 static int ip6_pkt_prohibit(struct sk_buff *skb);
229 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
230
231 static struct rt6_info ip6_prohibit_entry_template = {
232 .dst = {
233 .__refcnt = ATOMIC_INIT(1),
234 .__use = 1,
235 .obsolete = -1,
236 .error = -EACCES,
237 .input = ip6_pkt_prohibit,
238 .output = ip6_pkt_prohibit_out,
239 },
240 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
241 .rt6i_protocol = RTPROT_KERNEL,
242 .rt6i_metric = ~(u32) 0,
243 .rt6i_ref = ATOMIC_INIT(1),
244 };
245
246 static struct rt6_info ip6_blk_hole_entry_template = {
247 .dst = {
248 .__refcnt = ATOMIC_INIT(1),
249 .__use = 1,
250 .obsolete = -1,
251 .error = -EINVAL,
252 .input = dst_discard,
253 .output = dst_discard,
254 },
255 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
256 .rt6i_protocol = RTPROT_KERNEL,
257 .rt6i_metric = ~(u32) 0,
258 .rt6i_ref = ATOMIC_INIT(1),
259 };
260
261 #endif
262
263 /* allocate dst with ip6_dst_ops */
264 static inline struct rt6_info *ip6_dst_alloc(struct dst_ops *ops,
265 struct net_device *dev,
266 int flags)
267 {
268 struct rt6_info *rt = dst_alloc(ops, dev, 0, 0, flags);
269
270 if (rt)
271 memset(&rt->rt6i_table, 0,
272 sizeof(*rt) - sizeof(struct dst_entry));
273
274 return rt;
275 }
276
277 static void ip6_dst_destroy(struct dst_entry *dst)
278 {
279 struct rt6_info *rt = (struct rt6_info *)dst;
280 struct inet6_dev *idev = rt->rt6i_idev;
281 struct inet_peer *peer = rt->rt6i_peer;
282
283 if (!(rt->dst.flags & DST_HOST))
284 dst_destroy_metrics_generic(dst);
285
286 if (idev) {
287 rt->rt6i_idev = NULL;
288 in6_dev_put(idev);
289 }
290
291 if (!(rt->rt6i_flags & RTF_EXPIRES) && dst->from)
292 dst_release(dst->from);
293
294 if (peer) {
295 rt->rt6i_peer = NULL;
296 inet_putpeer(peer);
297 }
298 }
299
300 static atomic_t __rt6_peer_genid = ATOMIC_INIT(0);
301
302 static u32 rt6_peer_genid(void)
303 {
304 return atomic_read(&__rt6_peer_genid);
305 }
306
307 void rt6_bind_peer(struct rt6_info *rt, int create)
308 {
309 struct inet_peer *peer;
310
311 peer = inet_getpeer_v6(&rt->rt6i_dst.addr, create);
312 if (peer && cmpxchg(&rt->rt6i_peer, NULL, peer) != NULL)
313 inet_putpeer(peer);
314 else
315 rt->rt6i_peer_genid = rt6_peer_genid();
316 }
317
318 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
319 int how)
320 {
321 struct rt6_info *rt = (struct rt6_info *)dst;
322 struct inet6_dev *idev = rt->rt6i_idev;
323 struct net_device *loopback_dev =
324 dev_net(dev)->loopback_dev;
325
326 if (dev != loopback_dev && idev && idev->dev == dev) {
327 struct inet6_dev *loopback_idev =
328 in6_dev_get(loopback_dev);
329 if (loopback_idev) {
330 rt->rt6i_idev = loopback_idev;
331 in6_dev_put(idev);
332 }
333 }
334 }
335
336 static bool rt6_check_expired(const struct rt6_info *rt)
337 {
338 struct rt6_info *ort = NULL;
339
340 if (rt->rt6i_flags & RTF_EXPIRES) {
341 if (time_after(jiffies, rt->dst.expires))
342 return true;
343 } else if (rt->dst.from) {
344 ort = (struct rt6_info *) rt->dst.from;
345 return (ort->rt6i_flags & RTF_EXPIRES) &&
346 time_after(jiffies, ort->dst.expires);
347 }
348 return false;
349 }
350
351 static bool rt6_need_strict(const struct in6_addr *daddr)
352 {
353 return ipv6_addr_type(daddr) &
354 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
355 }
356
357 /*
358 * Route lookup. Any table->tb6_lock is implied.
359 */
360
361 static inline struct rt6_info *rt6_device_match(struct net *net,
362 struct rt6_info *rt,
363 const struct in6_addr *saddr,
364 int oif,
365 int flags)
366 {
367 struct rt6_info *local = NULL;
368 struct rt6_info *sprt;
369
370 if (!oif && ipv6_addr_any(saddr))
371 goto out;
372
373 for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
374 struct net_device *dev = sprt->dst.dev;
375
376 if (oif) {
377 if (dev->ifindex == oif)
378 return sprt;
379 if (dev->flags & IFF_LOOPBACK) {
380 if (!sprt->rt6i_idev ||
381 sprt->rt6i_idev->dev->ifindex != oif) {
382 if (flags & RT6_LOOKUP_F_IFACE && oif)
383 continue;
384 if (local && (!oif ||
385 local->rt6i_idev->dev->ifindex == oif))
386 continue;
387 }
388 local = sprt;
389 }
390 } else {
391 if (ipv6_chk_addr(net, saddr, dev,
392 flags & RT6_LOOKUP_F_IFACE))
393 return sprt;
394 }
395 }
396
397 if (oif) {
398 if (local)
399 return local;
400
401 if (flags & RT6_LOOKUP_F_IFACE)
402 return net->ipv6.ip6_null_entry;
403 }
404 out:
405 return rt;
406 }
407
408 #ifdef CONFIG_IPV6_ROUTER_PREF
409 static void rt6_probe(struct rt6_info *rt)
410 {
411 struct neighbour *neigh;
412 /*
413 * Okay, this does not seem to be appropriate
414 * for now, however, we need to check if it
415 * is really so; aka Router Reachability Probing.
416 *
417 * Router Reachability Probe MUST be rate-limited
418 * to no more than one per minute.
419 */
420 rcu_read_lock();
421 neigh = rt ? dst_get_neighbour_noref(&rt->dst) : NULL;
422 if (!neigh || (neigh->nud_state & NUD_VALID))
423 goto out;
424 read_lock_bh(&neigh->lock);
425 if (!(neigh->nud_state & NUD_VALID) &&
426 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
427 struct in6_addr mcaddr;
428 struct in6_addr *target;
429
430 neigh->updated = jiffies;
431 read_unlock_bh(&neigh->lock);
432
433 target = (struct in6_addr *)&neigh->primary_key;
434 addrconf_addr_solict_mult(target, &mcaddr);
435 ndisc_send_ns(rt->dst.dev, NULL, target, &mcaddr, NULL);
436 } else {
437 read_unlock_bh(&neigh->lock);
438 }
439 out:
440 rcu_read_unlock();
441 }
442 #else
443 static inline void rt6_probe(struct rt6_info *rt)
444 {
445 }
446 #endif
447
448 /*
449 * Default Router Selection (RFC 2461 6.3.6)
450 */
451 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
452 {
453 struct net_device *dev = rt->dst.dev;
454 if (!oif || dev->ifindex == oif)
455 return 2;
456 if ((dev->flags & IFF_LOOPBACK) &&
457 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
458 return 1;
459 return 0;
460 }
461
462 static inline int rt6_check_neigh(struct rt6_info *rt)
463 {
464 struct neighbour *neigh;
465 int m;
466
467 rcu_read_lock();
468 neigh = dst_get_neighbour_noref(&rt->dst);
469 if (rt->rt6i_flags & RTF_NONEXTHOP ||
470 !(rt->rt6i_flags & RTF_GATEWAY))
471 m = 1;
472 else if (neigh) {
473 read_lock_bh(&neigh->lock);
474 if (neigh->nud_state & NUD_VALID)
475 m = 2;
476 #ifdef CONFIG_IPV6_ROUTER_PREF
477 else if (neigh->nud_state & NUD_FAILED)
478 m = 0;
479 #endif
480 else
481 m = 1;
482 read_unlock_bh(&neigh->lock);
483 } else
484 m = 0;
485 rcu_read_unlock();
486 return m;
487 }
488
489 static int rt6_score_route(struct rt6_info *rt, int oif,
490 int strict)
491 {
492 int m, n;
493
494 m = rt6_check_dev(rt, oif);
495 if (!m && (strict & RT6_LOOKUP_F_IFACE))
496 return -1;
497 #ifdef CONFIG_IPV6_ROUTER_PREF
498 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
499 #endif
500 n = rt6_check_neigh(rt);
501 if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
502 return -1;
503 return m;
504 }
505
506 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
507 int *mpri, struct rt6_info *match)
508 {
509 int m;
510
511 if (rt6_check_expired(rt))
512 goto out;
513
514 m = rt6_score_route(rt, oif, strict);
515 if (m < 0)
516 goto out;
517
518 if (m > *mpri) {
519 if (strict & RT6_LOOKUP_F_REACHABLE)
520 rt6_probe(match);
521 *mpri = m;
522 match = rt;
523 } else if (strict & RT6_LOOKUP_F_REACHABLE) {
524 rt6_probe(rt);
525 }
526
527 out:
528 return match;
529 }
530
531 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
532 struct rt6_info *rr_head,
533 u32 metric, int oif, int strict)
534 {
535 struct rt6_info *rt, *match;
536 int mpri = -1;
537
538 match = NULL;
539 for (rt = rr_head; rt && rt->rt6i_metric == metric;
540 rt = rt->dst.rt6_next)
541 match = find_match(rt, oif, strict, &mpri, match);
542 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
543 rt = rt->dst.rt6_next)
544 match = find_match(rt, oif, strict, &mpri, match);
545
546 return match;
547 }
548
549 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
550 {
551 struct rt6_info *match, *rt0;
552 struct net *net;
553
554 rt0 = fn->rr_ptr;
555 if (!rt0)
556 fn->rr_ptr = rt0 = fn->leaf;
557
558 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
559
560 if (!match &&
561 (strict & RT6_LOOKUP_F_REACHABLE)) {
562 struct rt6_info *next = rt0->dst.rt6_next;
563
564 /* no entries matched; do round-robin */
565 if (!next || next->rt6i_metric != rt0->rt6i_metric)
566 next = fn->leaf;
567
568 if (next != rt0)
569 fn->rr_ptr = next;
570 }
571
572 net = dev_net(rt0->dst.dev);
573 return match ? match : net->ipv6.ip6_null_entry;
574 }
575
576 #ifdef CONFIG_IPV6_ROUTE_INFO
577 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
578 const struct in6_addr *gwaddr)
579 {
580 struct net *net = dev_net(dev);
581 struct route_info *rinfo = (struct route_info *) opt;
582 struct in6_addr prefix_buf, *prefix;
583 unsigned int pref;
584 unsigned long lifetime;
585 struct rt6_info *rt;
586
587 if (len < sizeof(struct route_info)) {
588 return -EINVAL;
589 }
590
591 /* Sanity check for prefix_len and length */
592 if (rinfo->length > 3) {
593 return -EINVAL;
594 } else if (rinfo->prefix_len > 128) {
595 return -EINVAL;
596 } else if (rinfo->prefix_len > 64) {
597 if (rinfo->length < 2) {
598 return -EINVAL;
599 }
600 } else if (rinfo->prefix_len > 0) {
601 if (rinfo->length < 1) {
602 return -EINVAL;
603 }
604 }
605
606 pref = rinfo->route_pref;
607 if (pref == ICMPV6_ROUTER_PREF_INVALID)
608 return -EINVAL;
609
610 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
611
612 if (rinfo->length == 3)
613 prefix = (struct in6_addr *)rinfo->prefix;
614 else {
615 /* this function is safe */
616 ipv6_addr_prefix(&prefix_buf,
617 (struct in6_addr *)rinfo->prefix,
618 rinfo->prefix_len);
619 prefix = &prefix_buf;
620 }
621
622 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr,
623 dev->ifindex);
624
625 if (rt && !lifetime) {
626 ip6_del_rt(rt);
627 rt = NULL;
628 }
629
630 if (!rt && lifetime)
631 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
632 pref);
633 else if (rt)
634 rt->rt6i_flags = RTF_ROUTEINFO |
635 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
636
637 if (rt) {
638 if (!addrconf_finite_timeout(lifetime))
639 rt6_clean_expires(rt);
640 else
641 rt6_set_expires(rt, jiffies + HZ * lifetime);
642
643 dst_release(&rt->dst);
644 }
645 return 0;
646 }
647 #endif
648
649 #define BACKTRACK(__net, saddr) \
650 do { \
651 if (rt == __net->ipv6.ip6_null_entry) { \
652 struct fib6_node *pn; \
653 while (1) { \
654 if (fn->fn_flags & RTN_TL_ROOT) \
655 goto out; \
656 pn = fn->parent; \
657 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
658 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
659 else \
660 fn = pn; \
661 if (fn->fn_flags & RTN_RTINFO) \
662 goto restart; \
663 } \
664 } \
665 } while (0)
666
667 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
668 struct fib6_table *table,
669 struct flowi6 *fl6, int flags)
670 {
671 struct fib6_node *fn;
672 struct rt6_info *rt;
673
674 read_lock_bh(&table->tb6_lock);
675 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
676 restart:
677 rt = fn->leaf;
678 rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
679 BACKTRACK(net, &fl6->saddr);
680 out:
681 dst_use(&rt->dst, jiffies);
682 read_unlock_bh(&table->tb6_lock);
683 return rt;
684
685 }
686
687 struct dst_entry * ip6_route_lookup(struct net *net, struct flowi6 *fl6,
688 int flags)
689 {
690 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
691 }
692 EXPORT_SYMBOL_GPL(ip6_route_lookup);
693
694 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
695 const struct in6_addr *saddr, int oif, int strict)
696 {
697 struct flowi6 fl6 = {
698 .flowi6_oif = oif,
699 .daddr = *daddr,
700 };
701 struct dst_entry *dst;
702 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
703
704 if (saddr) {
705 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
706 flags |= RT6_LOOKUP_F_HAS_SADDR;
707 }
708
709 dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
710 if (dst->error == 0)
711 return (struct rt6_info *) dst;
712
713 dst_release(dst);
714
715 return NULL;
716 }
717
718 EXPORT_SYMBOL(rt6_lookup);
719
720 /* ip6_ins_rt is called with FREE table->tb6_lock.
721 It takes new route entry, the addition fails by any reason the
722 route is freed. In any case, if caller does not hold it, it may
723 be destroyed.
724 */
725
726 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
727 {
728 int err;
729 struct fib6_table *table;
730
731 table = rt->rt6i_table;
732 write_lock_bh(&table->tb6_lock);
733 err = fib6_add(&table->tb6_root, rt, info);
734 write_unlock_bh(&table->tb6_lock);
735
736 return err;
737 }
738
739 int ip6_ins_rt(struct rt6_info *rt)
740 {
741 struct nl_info info = {
742 .nl_net = dev_net(rt->dst.dev),
743 };
744 return __ip6_ins_rt(rt, &info);
745 }
746
747 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort,
748 const struct in6_addr *daddr,
749 const struct in6_addr *saddr)
750 {
751 struct rt6_info *rt;
752
753 /*
754 * Clone the route.
755 */
756
757 rt = ip6_rt_copy(ort, daddr);
758
759 if (rt) {
760 int attempts = !in_softirq();
761
762 if (!(rt->rt6i_flags & RTF_GATEWAY)) {
763 if (ort->rt6i_dst.plen != 128 &&
764 ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
765 rt->rt6i_flags |= RTF_ANYCAST;
766 rt->rt6i_gateway = *daddr;
767 }
768
769 rt->rt6i_flags |= RTF_CACHE;
770
771 #ifdef CONFIG_IPV6_SUBTREES
772 if (rt->rt6i_src.plen && saddr) {
773 rt->rt6i_src.addr = *saddr;
774 rt->rt6i_src.plen = 128;
775 }
776 #endif
777
778 retry:
779 if (rt6_bind_neighbour(rt, rt->dst.dev)) {
780 struct net *net = dev_net(rt->dst.dev);
781 int saved_rt_min_interval =
782 net->ipv6.sysctl.ip6_rt_gc_min_interval;
783 int saved_rt_elasticity =
784 net->ipv6.sysctl.ip6_rt_gc_elasticity;
785
786 if (attempts-- > 0) {
787 net->ipv6.sysctl.ip6_rt_gc_elasticity = 1;
788 net->ipv6.sysctl.ip6_rt_gc_min_interval = 0;
789
790 ip6_dst_gc(&net->ipv6.ip6_dst_ops);
791
792 net->ipv6.sysctl.ip6_rt_gc_elasticity =
793 saved_rt_elasticity;
794 net->ipv6.sysctl.ip6_rt_gc_min_interval =
795 saved_rt_min_interval;
796 goto retry;
797 }
798
799 net_warn_ratelimited("Neighbour table overflow\n");
800 dst_free(&rt->dst);
801 return NULL;
802 }
803 }
804
805 return rt;
806 }
807
808 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort,
809 const struct in6_addr *daddr)
810 {
811 struct rt6_info *rt = ip6_rt_copy(ort, daddr);
812
813 if (rt) {
814 rt->rt6i_flags |= RTF_CACHE;
815 dst_set_neighbour(&rt->dst, neigh_clone(dst_get_neighbour_noref_raw(&ort->dst)));
816 }
817 return rt;
818 }
819
820 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
821 struct flowi6 *fl6, int flags)
822 {
823 struct fib6_node *fn;
824 struct rt6_info *rt, *nrt;
825 int strict = 0;
826 int attempts = 3;
827 int err;
828 int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
829
830 strict |= flags & RT6_LOOKUP_F_IFACE;
831
832 relookup:
833 read_lock_bh(&table->tb6_lock);
834
835 restart_2:
836 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
837
838 restart:
839 rt = rt6_select(fn, oif, strict | reachable);
840
841 BACKTRACK(net, &fl6->saddr);
842 if (rt == net->ipv6.ip6_null_entry ||
843 rt->rt6i_flags & RTF_CACHE)
844 goto out;
845
846 dst_hold(&rt->dst);
847 read_unlock_bh(&table->tb6_lock);
848
849 if (!dst_get_neighbour_noref_raw(&rt->dst) && !(rt->rt6i_flags & RTF_NONEXTHOP))
850 nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr);
851 else if (!(rt->dst.flags & DST_HOST))
852 nrt = rt6_alloc_clone(rt, &fl6->daddr);
853 else
854 goto out2;
855
856 dst_release(&rt->dst);
857 rt = nrt ? : net->ipv6.ip6_null_entry;
858
859 dst_hold(&rt->dst);
860 if (nrt) {
861 err = ip6_ins_rt(nrt);
862 if (!err)
863 goto out2;
864 }
865
866 if (--attempts <= 0)
867 goto out2;
868
869 /*
870 * Race condition! In the gap, when table->tb6_lock was
871 * released someone could insert this route. Relookup.
872 */
873 dst_release(&rt->dst);
874 goto relookup;
875
876 out:
877 if (reachable) {
878 reachable = 0;
879 goto restart_2;
880 }
881 dst_hold(&rt->dst);
882 read_unlock_bh(&table->tb6_lock);
883 out2:
884 rt->dst.lastuse = jiffies;
885 rt->dst.__use++;
886
887 return rt;
888 }
889
890 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
891 struct flowi6 *fl6, int flags)
892 {
893 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
894 }
895
896 static struct dst_entry *ip6_route_input_lookup(struct net *net,
897 struct net_device *dev,
898 struct flowi6 *fl6, int flags)
899 {
900 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
901 flags |= RT6_LOOKUP_F_IFACE;
902
903 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
904 }
905
906 void ip6_route_input(struct sk_buff *skb)
907 {
908 const struct ipv6hdr *iph = ipv6_hdr(skb);
909 struct net *net = dev_net(skb->dev);
910 int flags = RT6_LOOKUP_F_HAS_SADDR;
911 struct flowi6 fl6 = {
912 .flowi6_iif = skb->dev->ifindex,
913 .daddr = iph->daddr,
914 .saddr = iph->saddr,
915 .flowlabel = (* (__be32 *) iph) & IPV6_FLOWINFO_MASK,
916 .flowi6_mark = skb->mark,
917 .flowi6_proto = iph->nexthdr,
918 };
919
920 skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
921 }
922
923 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
924 struct flowi6 *fl6, int flags)
925 {
926 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
927 }
928
929 struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk,
930 struct flowi6 *fl6)
931 {
932 int flags = 0;
933
934 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr))
935 flags |= RT6_LOOKUP_F_IFACE;
936
937 if (!ipv6_addr_any(&fl6->saddr))
938 flags |= RT6_LOOKUP_F_HAS_SADDR;
939 else if (sk)
940 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
941
942 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
943 }
944
945 EXPORT_SYMBOL(ip6_route_output);
946
947 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
948 {
949 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
950 struct dst_entry *new = NULL;
951
952 rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, 0, 0);
953 if (rt) {
954 memset(&rt->rt6i_table, 0, sizeof(*rt) - sizeof(struct dst_entry));
955
956 new = &rt->dst;
957
958 new->__use = 1;
959 new->input = dst_discard;
960 new->output = dst_discard;
961
962 if (dst_metrics_read_only(&ort->dst))
963 new->_metrics = ort->dst._metrics;
964 else
965 dst_copy_metrics(new, &ort->dst);
966 rt->rt6i_idev = ort->rt6i_idev;
967 if (rt->rt6i_idev)
968 in6_dev_hold(rt->rt6i_idev);
969
970 rt->rt6i_gateway = ort->rt6i_gateway;
971 rt->rt6i_flags = ort->rt6i_flags;
972 rt6_clean_expires(rt);
973 rt->rt6i_metric = 0;
974
975 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
976 #ifdef CONFIG_IPV6_SUBTREES
977 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
978 #endif
979
980 dst_free(new);
981 }
982
983 dst_release(dst_orig);
984 return new ? new : ERR_PTR(-ENOMEM);
985 }
986
987 /*
988 * Destination cache support functions
989 */
990
991 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
992 {
993 struct rt6_info *rt;
994
995 rt = (struct rt6_info *) dst;
996
997 if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) {
998 if (rt->rt6i_peer_genid != rt6_peer_genid()) {
999 if (!rt->rt6i_peer)
1000 rt6_bind_peer(rt, 0);
1001 rt->rt6i_peer_genid = rt6_peer_genid();
1002 }
1003 return dst;
1004 }
1005 return NULL;
1006 }
1007
1008 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1009 {
1010 struct rt6_info *rt = (struct rt6_info *) dst;
1011
1012 if (rt) {
1013 if (rt->rt6i_flags & RTF_CACHE) {
1014 if (rt6_check_expired(rt)) {
1015 ip6_del_rt(rt);
1016 dst = NULL;
1017 }
1018 } else {
1019 dst_release(dst);
1020 dst = NULL;
1021 }
1022 }
1023 return dst;
1024 }
1025
1026 static void ip6_link_failure(struct sk_buff *skb)
1027 {
1028 struct rt6_info *rt;
1029
1030 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1031
1032 rt = (struct rt6_info *) skb_dst(skb);
1033 if (rt) {
1034 if (rt->rt6i_flags & RTF_CACHE)
1035 rt6_update_expires(rt, 0);
1036 else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
1037 rt->rt6i_node->fn_sernum = -1;
1038 }
1039 }
1040
1041 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
1042 {
1043 struct rt6_info *rt6 = (struct rt6_info*)dst;
1044
1045 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
1046 rt6->rt6i_flags |= RTF_MODIFIED;
1047 if (mtu < IPV6_MIN_MTU) {
1048 u32 features = dst_metric(dst, RTAX_FEATURES);
1049 mtu = IPV6_MIN_MTU;
1050 features |= RTAX_FEATURE_ALLFRAG;
1051 dst_metric_set(dst, RTAX_FEATURES, features);
1052 }
1053 dst_metric_set(dst, RTAX_MTU, mtu);
1054 }
1055 }
1056
1057 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1058 {
1059 struct net_device *dev = dst->dev;
1060 unsigned int mtu = dst_mtu(dst);
1061 struct net *net = dev_net(dev);
1062
1063 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1064
1065 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1066 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1067
1068 /*
1069 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1070 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1071 * IPV6_MAXPLEN is also valid and means: "any MSS,
1072 * rely only on pmtu discovery"
1073 */
1074 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1075 mtu = IPV6_MAXPLEN;
1076 return mtu;
1077 }
1078
1079 static unsigned int ip6_mtu(const struct dst_entry *dst)
1080 {
1081 struct inet6_dev *idev;
1082 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
1083
1084 if (mtu)
1085 return mtu;
1086
1087 mtu = IPV6_MIN_MTU;
1088
1089 rcu_read_lock();
1090 idev = __in6_dev_get(dst->dev);
1091 if (idev)
1092 mtu = idev->cnf.mtu6;
1093 rcu_read_unlock();
1094
1095 return mtu;
1096 }
1097
1098 static struct dst_entry *icmp6_dst_gc_list;
1099 static DEFINE_SPINLOCK(icmp6_dst_lock);
1100
1101 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1102 struct neighbour *neigh,
1103 struct flowi6 *fl6)
1104 {
1105 struct dst_entry *dst;
1106 struct rt6_info *rt;
1107 struct inet6_dev *idev = in6_dev_get(dev);
1108 struct net *net = dev_net(dev);
1109
1110 if (unlikely(!idev))
1111 return ERR_PTR(-ENODEV);
1112
1113 rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops, dev, 0);
1114 if (unlikely(!rt)) {
1115 in6_dev_put(idev);
1116 dst = ERR_PTR(-ENOMEM);
1117 goto out;
1118 }
1119
1120 if (neigh)
1121 neigh_hold(neigh);
1122 else {
1123 neigh = ip6_neigh_lookup(&rt->dst, &fl6->daddr);
1124 if (IS_ERR(neigh)) {
1125 in6_dev_put(idev);
1126 dst_free(&rt->dst);
1127 return ERR_CAST(neigh);
1128 }
1129 }
1130
1131 rt->dst.flags |= DST_HOST;
1132 rt->dst.output = ip6_output;
1133 dst_set_neighbour(&rt->dst, neigh);
1134 atomic_set(&rt->dst.__refcnt, 1);
1135 rt->rt6i_dst.addr = fl6->daddr;
1136 rt->rt6i_dst.plen = 128;
1137 rt->rt6i_idev = idev;
1138 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255);
1139
1140 spin_lock_bh(&icmp6_dst_lock);
1141 rt->dst.next = icmp6_dst_gc_list;
1142 icmp6_dst_gc_list = &rt->dst;
1143 spin_unlock_bh(&icmp6_dst_lock);
1144
1145 fib6_force_start_gc(net);
1146
1147 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1148
1149 out:
1150 return dst;
1151 }
1152
1153 int icmp6_dst_gc(void)
1154 {
1155 struct dst_entry *dst, **pprev;
1156 int more = 0;
1157
1158 spin_lock_bh(&icmp6_dst_lock);
1159 pprev = &icmp6_dst_gc_list;
1160
1161 while ((dst = *pprev) != NULL) {
1162 if (!atomic_read(&dst->__refcnt)) {
1163 *pprev = dst->next;
1164 dst_free(dst);
1165 } else {
1166 pprev = &dst->next;
1167 ++more;
1168 }
1169 }
1170
1171 spin_unlock_bh(&icmp6_dst_lock);
1172
1173 return more;
1174 }
1175
1176 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1177 void *arg)
1178 {
1179 struct dst_entry *dst, **pprev;
1180
1181 spin_lock_bh(&icmp6_dst_lock);
1182 pprev = &icmp6_dst_gc_list;
1183 while ((dst = *pprev) != NULL) {
1184 struct rt6_info *rt = (struct rt6_info *) dst;
1185 if (func(rt, arg)) {
1186 *pprev = dst->next;
1187 dst_free(dst);
1188 } else {
1189 pprev = &dst->next;
1190 }
1191 }
1192 spin_unlock_bh(&icmp6_dst_lock);
1193 }
1194
1195 static int ip6_dst_gc(struct dst_ops *ops)
1196 {
1197 unsigned long now = jiffies;
1198 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1199 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1200 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1201 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1202 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1203 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1204 int entries;
1205
1206 entries = dst_entries_get_fast(ops);
1207 if (time_after(rt_last_gc + rt_min_interval, now) &&
1208 entries <= rt_max_size)
1209 goto out;
1210
1211 net->ipv6.ip6_rt_gc_expire++;
1212 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net);
1213 net->ipv6.ip6_rt_last_gc = now;
1214 entries = dst_entries_get_slow(ops);
1215 if (entries < ops->gc_thresh)
1216 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1217 out:
1218 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1219 return entries > rt_max_size;
1220 }
1221
1222 /* Clean host part of a prefix. Not necessary in radix tree,
1223 but results in cleaner routing tables.
1224
1225 Remove it only when all the things will work!
1226 */
1227
1228 int ip6_dst_hoplimit(struct dst_entry *dst)
1229 {
1230 int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
1231 if (hoplimit == 0) {
1232 struct net_device *dev = dst->dev;
1233 struct inet6_dev *idev;
1234
1235 rcu_read_lock();
1236 idev = __in6_dev_get(dev);
1237 if (idev)
1238 hoplimit = idev->cnf.hop_limit;
1239 else
1240 hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
1241 rcu_read_unlock();
1242 }
1243 return hoplimit;
1244 }
1245 EXPORT_SYMBOL(ip6_dst_hoplimit);
1246
1247 /*
1248 *
1249 */
1250
1251 int ip6_route_add(struct fib6_config *cfg)
1252 {
1253 int err;
1254 struct net *net = cfg->fc_nlinfo.nl_net;
1255 struct rt6_info *rt = NULL;
1256 struct net_device *dev = NULL;
1257 struct inet6_dev *idev = NULL;
1258 struct fib6_table *table;
1259 int addr_type;
1260
1261 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1262 return -EINVAL;
1263 #ifndef CONFIG_IPV6_SUBTREES
1264 if (cfg->fc_src_len)
1265 return -EINVAL;
1266 #endif
1267 if (cfg->fc_ifindex) {
1268 err = -ENODEV;
1269 dev = dev_get_by_index(net, cfg->fc_ifindex);
1270 if (!dev)
1271 goto out;
1272 idev = in6_dev_get(dev);
1273 if (!idev)
1274 goto out;
1275 }
1276
1277 if (cfg->fc_metric == 0)
1278 cfg->fc_metric = IP6_RT_PRIO_USER;
1279
1280 err = -ENOBUFS;
1281 if (cfg->fc_nlinfo.nlh &&
1282 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1283 table = fib6_get_table(net, cfg->fc_table);
1284 if (!table) {
1285 pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1286 table = fib6_new_table(net, cfg->fc_table);
1287 }
1288 } else {
1289 table = fib6_new_table(net, cfg->fc_table);
1290 }
1291
1292 if (!table)
1293 goto out;
1294
1295 rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops, NULL, DST_NOCOUNT);
1296
1297 if (!rt) {
1298 err = -ENOMEM;
1299 goto out;
1300 }
1301
1302 rt->dst.obsolete = -1;
1303
1304 if (cfg->fc_flags & RTF_EXPIRES)
1305 rt6_set_expires(rt, jiffies +
1306 clock_t_to_jiffies(cfg->fc_expires));
1307 else
1308 rt6_clean_expires(rt);
1309
1310 if (cfg->fc_protocol == RTPROT_UNSPEC)
1311 cfg->fc_protocol = RTPROT_BOOT;
1312 rt->rt6i_protocol = cfg->fc_protocol;
1313
1314 addr_type = ipv6_addr_type(&cfg->fc_dst);
1315
1316 if (addr_type & IPV6_ADDR_MULTICAST)
1317 rt->dst.input = ip6_mc_input;
1318 else if (cfg->fc_flags & RTF_LOCAL)
1319 rt->dst.input = ip6_input;
1320 else
1321 rt->dst.input = ip6_forward;
1322
1323 rt->dst.output = ip6_output;
1324
1325 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1326 rt->rt6i_dst.plen = cfg->fc_dst_len;
1327 if (rt->rt6i_dst.plen == 128)
1328 rt->dst.flags |= DST_HOST;
1329
1330 if (!(rt->dst.flags & DST_HOST) && cfg->fc_mx) {
1331 u32 *metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1332 if (!metrics) {
1333 err = -ENOMEM;
1334 goto out;
1335 }
1336 dst_init_metrics(&rt->dst, metrics, 0);
1337 }
1338 #ifdef CONFIG_IPV6_SUBTREES
1339 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1340 rt->rt6i_src.plen = cfg->fc_src_len;
1341 #endif
1342
1343 rt->rt6i_metric = cfg->fc_metric;
1344
1345 /* We cannot add true routes via loopback here,
1346 they would result in kernel looping; promote them to reject routes
1347 */
1348 if ((cfg->fc_flags & RTF_REJECT) ||
1349 (dev && (dev->flags & IFF_LOOPBACK) &&
1350 !(addr_type & IPV6_ADDR_LOOPBACK) &&
1351 !(cfg->fc_flags & RTF_LOCAL))) {
1352 /* hold loopback dev/idev if we haven't done so. */
1353 if (dev != net->loopback_dev) {
1354 if (dev) {
1355 dev_put(dev);
1356 in6_dev_put(idev);
1357 }
1358 dev = net->loopback_dev;
1359 dev_hold(dev);
1360 idev = in6_dev_get(dev);
1361 if (!idev) {
1362 err = -ENODEV;
1363 goto out;
1364 }
1365 }
1366 rt->dst.output = ip6_pkt_discard_out;
1367 rt->dst.input = ip6_pkt_discard;
1368 rt->dst.error = -ENETUNREACH;
1369 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1370 goto install_route;
1371 }
1372
1373 if (cfg->fc_flags & RTF_GATEWAY) {
1374 const struct in6_addr *gw_addr;
1375 int gwa_type;
1376
1377 gw_addr = &cfg->fc_gateway;
1378 rt->rt6i_gateway = *gw_addr;
1379 gwa_type = ipv6_addr_type(gw_addr);
1380
1381 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1382 struct rt6_info *grt;
1383
1384 /* IPv6 strictly inhibits using not link-local
1385 addresses as nexthop address.
1386 Otherwise, router will not able to send redirects.
1387 It is very good, but in some (rare!) circumstances
1388 (SIT, PtP, NBMA NOARP links) it is handy to allow
1389 some exceptions. --ANK
1390 */
1391 err = -EINVAL;
1392 if (!(gwa_type & IPV6_ADDR_UNICAST))
1393 goto out;
1394
1395 grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1396
1397 err = -EHOSTUNREACH;
1398 if (!grt)
1399 goto out;
1400 if (dev) {
1401 if (dev != grt->dst.dev) {
1402 dst_release(&grt->dst);
1403 goto out;
1404 }
1405 } else {
1406 dev = grt->dst.dev;
1407 idev = grt->rt6i_idev;
1408 dev_hold(dev);
1409 in6_dev_hold(grt->rt6i_idev);
1410 }
1411 if (!(grt->rt6i_flags & RTF_GATEWAY))
1412 err = 0;
1413 dst_release(&grt->dst);
1414
1415 if (err)
1416 goto out;
1417 }
1418 err = -EINVAL;
1419 if (!dev || (dev->flags & IFF_LOOPBACK))
1420 goto out;
1421 }
1422
1423 err = -ENODEV;
1424 if (!dev)
1425 goto out;
1426
1427 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1428 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1429 err = -EINVAL;
1430 goto out;
1431 }
1432 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1433 rt->rt6i_prefsrc.plen = 128;
1434 } else
1435 rt->rt6i_prefsrc.plen = 0;
1436
1437 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1438 err = rt6_bind_neighbour(rt, dev);
1439 if (err)
1440 goto out;
1441 }
1442
1443 rt->rt6i_flags = cfg->fc_flags;
1444
1445 install_route:
1446 if (cfg->fc_mx) {
1447 struct nlattr *nla;
1448 int remaining;
1449
1450 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1451 int type = nla_type(nla);
1452
1453 if (type) {
1454 if (type > RTAX_MAX) {
1455 err = -EINVAL;
1456 goto out;
1457 }
1458
1459 dst_metric_set(&rt->dst, type, nla_get_u32(nla));
1460 }
1461 }
1462 }
1463
1464 rt->dst.dev = dev;
1465 rt->rt6i_idev = idev;
1466 rt->rt6i_table = table;
1467
1468 cfg->fc_nlinfo.nl_net = dev_net(dev);
1469
1470 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1471
1472 out:
1473 if (dev)
1474 dev_put(dev);
1475 if (idev)
1476 in6_dev_put(idev);
1477 if (rt)
1478 dst_free(&rt->dst);
1479 return err;
1480 }
1481
1482 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1483 {
1484 int err;
1485 struct fib6_table *table;
1486 struct net *net = dev_net(rt->dst.dev);
1487
1488 if (rt == net->ipv6.ip6_null_entry)
1489 return -ENOENT;
1490
1491 table = rt->rt6i_table;
1492 write_lock_bh(&table->tb6_lock);
1493
1494 err = fib6_del(rt, info);
1495 dst_release(&rt->dst);
1496
1497 write_unlock_bh(&table->tb6_lock);
1498
1499 return err;
1500 }
1501
1502 int ip6_del_rt(struct rt6_info *rt)
1503 {
1504 struct nl_info info = {
1505 .nl_net = dev_net(rt->dst.dev),
1506 };
1507 return __ip6_del_rt(rt, &info);
1508 }
1509
1510 static int ip6_route_del(struct fib6_config *cfg)
1511 {
1512 struct fib6_table *table;
1513 struct fib6_node *fn;
1514 struct rt6_info *rt;
1515 int err = -ESRCH;
1516
1517 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
1518 if (!table)
1519 return err;
1520
1521 read_lock_bh(&table->tb6_lock);
1522
1523 fn = fib6_locate(&table->tb6_root,
1524 &cfg->fc_dst, cfg->fc_dst_len,
1525 &cfg->fc_src, cfg->fc_src_len);
1526
1527 if (fn) {
1528 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1529 if (cfg->fc_ifindex &&
1530 (!rt->dst.dev ||
1531 rt->dst.dev->ifindex != cfg->fc_ifindex))
1532 continue;
1533 if (cfg->fc_flags & RTF_GATEWAY &&
1534 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1535 continue;
1536 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1537 continue;
1538 dst_hold(&rt->dst);
1539 read_unlock_bh(&table->tb6_lock);
1540
1541 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1542 }
1543 }
1544 read_unlock_bh(&table->tb6_lock);
1545
1546 return err;
1547 }
1548
1549 /*
1550 * Handle redirects
1551 */
1552 struct ip6rd_flowi {
1553 struct flowi6 fl6;
1554 struct in6_addr gateway;
1555 };
1556
1557 static struct rt6_info *__ip6_route_redirect(struct net *net,
1558 struct fib6_table *table,
1559 struct flowi6 *fl6,
1560 int flags)
1561 {
1562 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1563 struct rt6_info *rt;
1564 struct fib6_node *fn;
1565
1566 /*
1567 * Get the "current" route for this destination and
1568 * check if the redirect has come from approriate router.
1569 *
1570 * RFC 2461 specifies that redirects should only be
1571 * accepted if they come from the nexthop to the target.
1572 * Due to the way the routes are chosen, this notion
1573 * is a bit fuzzy and one might need to check all possible
1574 * routes.
1575 */
1576
1577 read_lock_bh(&table->tb6_lock);
1578 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1579 restart:
1580 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1581 /*
1582 * Current route is on-link; redirect is always invalid.
1583 *
1584 * Seems, previous statement is not true. It could
1585 * be node, which looks for us as on-link (f.e. proxy ndisc)
1586 * But then router serving it might decide, that we should
1587 * know truth 8)8) --ANK (980726).
1588 */
1589 if (rt6_check_expired(rt))
1590 continue;
1591 if (!(rt->rt6i_flags & RTF_GATEWAY))
1592 continue;
1593 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1594 continue;
1595 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1596 continue;
1597 break;
1598 }
1599
1600 if (!rt)
1601 rt = net->ipv6.ip6_null_entry;
1602 BACKTRACK(net, &fl6->saddr);
1603 out:
1604 dst_hold(&rt->dst);
1605
1606 read_unlock_bh(&table->tb6_lock);
1607
1608 return rt;
1609 };
1610
1611 static struct rt6_info *ip6_route_redirect(const struct in6_addr *dest,
1612 const struct in6_addr *src,
1613 const struct in6_addr *gateway,
1614 struct net_device *dev)
1615 {
1616 int flags = RT6_LOOKUP_F_HAS_SADDR;
1617 struct net *net = dev_net(dev);
1618 struct ip6rd_flowi rdfl = {
1619 .fl6 = {
1620 .flowi6_oif = dev->ifindex,
1621 .daddr = *dest,
1622 .saddr = *src,
1623 },
1624 };
1625
1626 rdfl.gateway = *gateway;
1627
1628 if (rt6_need_strict(dest))
1629 flags |= RT6_LOOKUP_F_IFACE;
1630
1631 return (struct rt6_info *)fib6_rule_lookup(net, &rdfl.fl6,
1632 flags, __ip6_route_redirect);
1633 }
1634
1635 void rt6_redirect(const struct in6_addr *dest, const struct in6_addr *src,
1636 const struct in6_addr *saddr,
1637 struct neighbour *neigh, u8 *lladdr, int on_link)
1638 {
1639 struct rt6_info *rt, *nrt = NULL;
1640 struct netevent_redirect netevent;
1641 struct net *net = dev_net(neigh->dev);
1642
1643 rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1644
1645 if (rt == net->ipv6.ip6_null_entry) {
1646 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
1647 goto out;
1648 }
1649
1650 /*
1651 * We have finally decided to accept it.
1652 */
1653
1654 neigh_update(neigh, lladdr, NUD_STALE,
1655 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1656 NEIGH_UPDATE_F_OVERRIDE|
1657 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1658 NEIGH_UPDATE_F_ISROUTER))
1659 );
1660
1661 /*
1662 * Redirect received -> path was valid.
1663 * Look, redirects are sent only in response to data packets,
1664 * so that this nexthop apparently is reachable. --ANK
1665 */
1666 dst_confirm(&rt->dst);
1667
1668 /* Duplicate redirect: silently ignore. */
1669 if (neigh == dst_get_neighbour_noref_raw(&rt->dst))
1670 goto out;
1671
1672 nrt = ip6_rt_copy(rt, dest);
1673 if (!nrt)
1674 goto out;
1675
1676 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1677 if (on_link)
1678 nrt->rt6i_flags &= ~RTF_GATEWAY;
1679
1680 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
1681 dst_set_neighbour(&nrt->dst, neigh_clone(neigh));
1682
1683 if (ip6_ins_rt(nrt))
1684 goto out;
1685
1686 netevent.old = &rt->dst;
1687 netevent.new = &nrt->dst;
1688 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1689
1690 if (rt->rt6i_flags & RTF_CACHE) {
1691 ip6_del_rt(rt);
1692 return;
1693 }
1694
1695 out:
1696 dst_release(&rt->dst);
1697 }
1698
1699 /*
1700 * Handle ICMP "packet too big" messages
1701 * i.e. Path MTU discovery
1702 */
1703
1704 static void rt6_do_pmtu_disc(const struct in6_addr *daddr, const struct in6_addr *saddr,
1705 struct net *net, u32 pmtu, int ifindex)
1706 {
1707 struct rt6_info *rt, *nrt;
1708 int allfrag = 0;
1709 again:
1710 rt = rt6_lookup(net, daddr, saddr, ifindex, 0);
1711 if (!rt)
1712 return;
1713
1714 if (rt6_check_expired(rt)) {
1715 ip6_del_rt(rt);
1716 goto again;
1717 }
1718
1719 if (pmtu >= dst_mtu(&rt->dst))
1720 goto out;
1721
1722 if (pmtu < IPV6_MIN_MTU) {
1723 /*
1724 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1725 * MTU (1280) and a fragment header should always be included
1726 * after a node receiving Too Big message reporting PMTU is
1727 * less than the IPv6 Minimum Link MTU.
1728 */
1729 pmtu = IPV6_MIN_MTU;
1730 allfrag = 1;
1731 }
1732
1733 /* New mtu received -> path was valid.
1734 They are sent only in response to data packets,
1735 so that this nexthop apparently is reachable. --ANK
1736 */
1737 dst_confirm(&rt->dst);
1738
1739 /* Host route. If it is static, it would be better
1740 not to override it, but add new one, so that
1741 when cache entry will expire old pmtu
1742 would return automatically.
1743 */
1744 if (rt->rt6i_flags & RTF_CACHE) {
1745 dst_metric_set(&rt->dst, RTAX_MTU, pmtu);
1746 if (allfrag) {
1747 u32 features = dst_metric(&rt->dst, RTAX_FEATURES);
1748 features |= RTAX_FEATURE_ALLFRAG;
1749 dst_metric_set(&rt->dst, RTAX_FEATURES, features);
1750 }
1751 rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1752 rt->rt6i_flags |= RTF_MODIFIED;
1753 goto out;
1754 }
1755
1756 /* Network route.
1757 Two cases are possible:
1758 1. It is connected route. Action: COW
1759 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1760 */
1761 if (!dst_get_neighbour_noref_raw(&rt->dst) && !(rt->rt6i_flags & RTF_NONEXTHOP))
1762 nrt = rt6_alloc_cow(rt, daddr, saddr);
1763 else
1764 nrt = rt6_alloc_clone(rt, daddr);
1765
1766 if (nrt) {
1767 dst_metric_set(&nrt->dst, RTAX_MTU, pmtu);
1768 if (allfrag) {
1769 u32 features = dst_metric(&nrt->dst, RTAX_FEATURES);
1770 features |= RTAX_FEATURE_ALLFRAG;
1771 dst_metric_set(&nrt->dst, RTAX_FEATURES, features);
1772 }
1773
1774 /* According to RFC 1981, detecting PMTU increase shouldn't be
1775 * happened within 5 mins, the recommended timer is 10 mins.
1776 * Here this route expiration time is set to ip6_rt_mtu_expires
1777 * which is 10 mins. After 10 mins the decreased pmtu is expired
1778 * and detecting PMTU increase will be automatically happened.
1779 */
1780 rt6_update_expires(nrt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1781 nrt->rt6i_flags |= RTF_DYNAMIC;
1782 ip6_ins_rt(nrt);
1783 }
1784 out:
1785 dst_release(&rt->dst);
1786 }
1787
1788 void rt6_pmtu_discovery(const struct in6_addr *daddr, const struct in6_addr *saddr,
1789 struct net_device *dev, u32 pmtu)
1790 {
1791 struct net *net = dev_net(dev);
1792
1793 /*
1794 * RFC 1981 states that a node "MUST reduce the size of the packets it
1795 * is sending along the path" that caused the Packet Too Big message.
1796 * Since it's not possible in the general case to determine which
1797 * interface was used to send the original packet, we update the MTU
1798 * on the interface that will be used to send future packets. We also
1799 * update the MTU on the interface that received the Packet Too Big in
1800 * case the original packet was forced out that interface with
1801 * SO_BINDTODEVICE or similar. This is the next best thing to the
1802 * correct behaviour, which would be to update the MTU on all
1803 * interfaces.
1804 */
1805 rt6_do_pmtu_disc(daddr, saddr, net, pmtu, 0);
1806 rt6_do_pmtu_disc(daddr, saddr, net, pmtu, dev->ifindex);
1807 }
1808
1809 /*
1810 * Misc support functions
1811 */
1812
1813 static struct rt6_info *ip6_rt_copy(struct rt6_info *ort,
1814 const struct in6_addr *dest)
1815 {
1816 struct net *net = dev_net(ort->dst.dev);
1817 struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops,
1818 ort->dst.dev, 0);
1819
1820 if (rt) {
1821 rt->dst.input = ort->dst.input;
1822 rt->dst.output = ort->dst.output;
1823 rt->dst.flags |= DST_HOST;
1824
1825 rt->rt6i_dst.addr = *dest;
1826 rt->rt6i_dst.plen = 128;
1827 dst_copy_metrics(&rt->dst, &ort->dst);
1828 rt->dst.error = ort->dst.error;
1829 rt->rt6i_idev = ort->rt6i_idev;
1830 if (rt->rt6i_idev)
1831 in6_dev_hold(rt->rt6i_idev);
1832 rt->dst.lastuse = jiffies;
1833
1834 rt->rt6i_gateway = ort->rt6i_gateway;
1835 rt->rt6i_flags = ort->rt6i_flags;
1836 if ((ort->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) ==
1837 (RTF_DEFAULT | RTF_ADDRCONF))
1838 rt6_set_from(rt, ort);
1839 else
1840 rt6_clean_expires(rt);
1841 rt->rt6i_metric = 0;
1842
1843 #ifdef CONFIG_IPV6_SUBTREES
1844 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1845 #endif
1846 memcpy(&rt->rt6i_prefsrc, &ort->rt6i_prefsrc, sizeof(struct rt6key));
1847 rt->rt6i_table = ort->rt6i_table;
1848 }
1849 return rt;
1850 }
1851
1852 #ifdef CONFIG_IPV6_ROUTE_INFO
1853 static struct rt6_info *rt6_get_route_info(struct net *net,
1854 const struct in6_addr *prefix, int prefixlen,
1855 const struct in6_addr *gwaddr, int ifindex)
1856 {
1857 struct fib6_node *fn;
1858 struct rt6_info *rt = NULL;
1859 struct fib6_table *table;
1860
1861 table = fib6_get_table(net, RT6_TABLE_INFO);
1862 if (!table)
1863 return NULL;
1864
1865 write_lock_bh(&table->tb6_lock);
1866 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1867 if (!fn)
1868 goto out;
1869
1870 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1871 if (rt->dst.dev->ifindex != ifindex)
1872 continue;
1873 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1874 continue;
1875 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1876 continue;
1877 dst_hold(&rt->dst);
1878 break;
1879 }
1880 out:
1881 write_unlock_bh(&table->tb6_lock);
1882 return rt;
1883 }
1884
1885 static struct rt6_info *rt6_add_route_info(struct net *net,
1886 const struct in6_addr *prefix, int prefixlen,
1887 const struct in6_addr *gwaddr, int ifindex,
1888 unsigned int pref)
1889 {
1890 struct fib6_config cfg = {
1891 .fc_table = RT6_TABLE_INFO,
1892 .fc_metric = IP6_RT_PRIO_USER,
1893 .fc_ifindex = ifindex,
1894 .fc_dst_len = prefixlen,
1895 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1896 RTF_UP | RTF_PREF(pref),
1897 .fc_nlinfo.pid = 0,
1898 .fc_nlinfo.nlh = NULL,
1899 .fc_nlinfo.nl_net = net,
1900 };
1901
1902 cfg.fc_dst = *prefix;
1903 cfg.fc_gateway = *gwaddr;
1904
1905 /* We should treat it as a default route if prefix length is 0. */
1906 if (!prefixlen)
1907 cfg.fc_flags |= RTF_DEFAULT;
1908
1909 ip6_route_add(&cfg);
1910
1911 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
1912 }
1913 #endif
1914
1915 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
1916 {
1917 struct rt6_info *rt;
1918 struct fib6_table *table;
1919
1920 table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
1921 if (!table)
1922 return NULL;
1923
1924 write_lock_bh(&table->tb6_lock);
1925 for (rt = table->tb6_root.leaf; rt; rt=rt->dst.rt6_next) {
1926 if (dev == rt->dst.dev &&
1927 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1928 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1929 break;
1930 }
1931 if (rt)
1932 dst_hold(&rt->dst);
1933 write_unlock_bh(&table->tb6_lock);
1934 return rt;
1935 }
1936
1937 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
1938 struct net_device *dev,
1939 unsigned int pref)
1940 {
1941 struct fib6_config cfg = {
1942 .fc_table = RT6_TABLE_DFLT,
1943 .fc_metric = IP6_RT_PRIO_USER,
1944 .fc_ifindex = dev->ifindex,
1945 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1946 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1947 .fc_nlinfo.pid = 0,
1948 .fc_nlinfo.nlh = NULL,
1949 .fc_nlinfo.nl_net = dev_net(dev),
1950 };
1951
1952 cfg.fc_gateway = *gwaddr;
1953
1954 ip6_route_add(&cfg);
1955
1956 return rt6_get_dflt_router(gwaddr, dev);
1957 }
1958
1959 void rt6_purge_dflt_routers(struct net *net)
1960 {
1961 struct rt6_info *rt;
1962 struct fib6_table *table;
1963
1964 /* NOTE: Keep consistent with rt6_get_dflt_router */
1965 table = fib6_get_table(net, RT6_TABLE_DFLT);
1966 if (!table)
1967 return;
1968
1969 restart:
1970 read_lock_bh(&table->tb6_lock);
1971 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
1972 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1973 dst_hold(&rt->dst);
1974 read_unlock_bh(&table->tb6_lock);
1975 ip6_del_rt(rt);
1976 goto restart;
1977 }
1978 }
1979 read_unlock_bh(&table->tb6_lock);
1980 }
1981
1982 static void rtmsg_to_fib6_config(struct net *net,
1983 struct in6_rtmsg *rtmsg,
1984 struct fib6_config *cfg)
1985 {
1986 memset(cfg, 0, sizeof(*cfg));
1987
1988 cfg->fc_table = RT6_TABLE_MAIN;
1989 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1990 cfg->fc_metric = rtmsg->rtmsg_metric;
1991 cfg->fc_expires = rtmsg->rtmsg_info;
1992 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1993 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1994 cfg->fc_flags = rtmsg->rtmsg_flags;
1995
1996 cfg->fc_nlinfo.nl_net = net;
1997
1998 cfg->fc_dst = rtmsg->rtmsg_dst;
1999 cfg->fc_src = rtmsg->rtmsg_src;
2000 cfg->fc_gateway = rtmsg->rtmsg_gateway;
2001 }
2002
2003 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2004 {
2005 struct fib6_config cfg;
2006 struct in6_rtmsg rtmsg;
2007 int err;
2008
2009 switch(cmd) {
2010 case SIOCADDRT: /* Add a route */
2011 case SIOCDELRT: /* Delete a route */
2012 if (!capable(CAP_NET_ADMIN))
2013 return -EPERM;
2014 err = copy_from_user(&rtmsg, arg,
2015 sizeof(struct in6_rtmsg));
2016 if (err)
2017 return -EFAULT;
2018
2019 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2020
2021 rtnl_lock();
2022 switch (cmd) {
2023 case SIOCADDRT:
2024 err = ip6_route_add(&cfg);
2025 break;
2026 case SIOCDELRT:
2027 err = ip6_route_del(&cfg);
2028 break;
2029 default:
2030 err = -EINVAL;
2031 }
2032 rtnl_unlock();
2033
2034 return err;
2035 }
2036
2037 return -EINVAL;
2038 }
2039
2040 /*
2041 * Drop the packet on the floor
2042 */
2043
2044 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2045 {
2046 int type;
2047 struct dst_entry *dst = skb_dst(skb);
2048 switch (ipstats_mib_noroutes) {
2049 case IPSTATS_MIB_INNOROUTES:
2050 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2051 if (type == IPV6_ADDR_ANY) {
2052 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2053 IPSTATS_MIB_INADDRERRORS);
2054 break;
2055 }
2056 /* FALLTHROUGH */
2057 case IPSTATS_MIB_OUTNOROUTES:
2058 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2059 ipstats_mib_noroutes);
2060 break;
2061 }
2062 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2063 kfree_skb(skb);
2064 return 0;
2065 }
2066
2067 static int ip6_pkt_discard(struct sk_buff *skb)
2068 {
2069 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2070 }
2071
2072 static int ip6_pkt_discard_out(struct sk_buff *skb)
2073 {
2074 skb->dev = skb_dst(skb)->dev;
2075 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2076 }
2077
2078 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2079
2080 static int ip6_pkt_prohibit(struct sk_buff *skb)
2081 {
2082 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2083 }
2084
2085 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
2086 {
2087 skb->dev = skb_dst(skb)->dev;
2088 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2089 }
2090
2091 #endif
2092
2093 /*
2094 * Allocate a dst for local (unicast / anycast) address.
2095 */
2096
2097 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2098 const struct in6_addr *addr,
2099 bool anycast)
2100 {
2101 struct net *net = dev_net(idev->dev);
2102 struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops,
2103 net->loopback_dev, 0);
2104 int err;
2105
2106 if (!rt) {
2107 net_warn_ratelimited("Maximum number of routes reached, consider increasing route/max_size\n");
2108 return ERR_PTR(-ENOMEM);
2109 }
2110
2111 in6_dev_hold(idev);
2112
2113 rt->dst.flags |= DST_HOST;
2114 rt->dst.input = ip6_input;
2115 rt->dst.output = ip6_output;
2116 rt->rt6i_idev = idev;
2117 rt->dst.obsolete = -1;
2118
2119 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2120 if (anycast)
2121 rt->rt6i_flags |= RTF_ANYCAST;
2122 else
2123 rt->rt6i_flags |= RTF_LOCAL;
2124 err = rt6_bind_neighbour(rt, rt->dst.dev);
2125 if (err) {
2126 dst_free(&rt->dst);
2127 return ERR_PTR(err);
2128 }
2129
2130 rt->rt6i_dst.addr = *addr;
2131 rt->rt6i_dst.plen = 128;
2132 rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2133
2134 atomic_set(&rt->dst.__refcnt, 1);
2135
2136 return rt;
2137 }
2138
2139 int ip6_route_get_saddr(struct net *net,
2140 struct rt6_info *rt,
2141 const struct in6_addr *daddr,
2142 unsigned int prefs,
2143 struct in6_addr *saddr)
2144 {
2145 struct inet6_dev *idev = ip6_dst_idev((struct dst_entry*)rt);
2146 int err = 0;
2147 if (rt->rt6i_prefsrc.plen)
2148 *saddr = rt->rt6i_prefsrc.addr;
2149 else
2150 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2151 daddr, prefs, saddr);
2152 return err;
2153 }
2154
2155 /* remove deleted ip from prefsrc entries */
2156 struct arg_dev_net_ip {
2157 struct net_device *dev;
2158 struct net *net;
2159 struct in6_addr *addr;
2160 };
2161
2162 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2163 {
2164 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2165 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2166 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2167
2168 if (((void *)rt->dst.dev == dev || !dev) &&
2169 rt != net->ipv6.ip6_null_entry &&
2170 ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2171 /* remove prefsrc entry */
2172 rt->rt6i_prefsrc.plen = 0;
2173 }
2174 return 0;
2175 }
2176
2177 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2178 {
2179 struct net *net = dev_net(ifp->idev->dev);
2180 struct arg_dev_net_ip adni = {
2181 .dev = ifp->idev->dev,
2182 .net = net,
2183 .addr = &ifp->addr,
2184 };
2185 fib6_clean_all(net, fib6_remove_prefsrc, 0, &adni);
2186 }
2187
2188 struct arg_dev_net {
2189 struct net_device *dev;
2190 struct net *net;
2191 };
2192
2193 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2194 {
2195 const struct arg_dev_net *adn = arg;
2196 const struct net_device *dev = adn->dev;
2197
2198 if ((rt->dst.dev == dev || !dev) &&
2199 rt != adn->net->ipv6.ip6_null_entry)
2200 return -1;
2201
2202 return 0;
2203 }
2204
2205 void rt6_ifdown(struct net *net, struct net_device *dev)
2206 {
2207 struct arg_dev_net adn = {
2208 .dev = dev,
2209 .net = net,
2210 };
2211
2212 fib6_clean_all(net, fib6_ifdown, 0, &adn);
2213 icmp6_clean_all(fib6_ifdown, &adn);
2214 }
2215
2216 struct rt6_mtu_change_arg {
2217 struct net_device *dev;
2218 unsigned int mtu;
2219 };
2220
2221 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2222 {
2223 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2224 struct inet6_dev *idev;
2225
2226 /* In IPv6 pmtu discovery is not optional,
2227 so that RTAX_MTU lock cannot disable it.
2228 We still use this lock to block changes
2229 caused by addrconf/ndisc.
2230 */
2231
2232 idev = __in6_dev_get(arg->dev);
2233 if (!idev)
2234 return 0;
2235
2236 /* For administrative MTU increase, there is no way to discover
2237 IPv6 PMTU increase, so PMTU increase should be updated here.
2238 Since RFC 1981 doesn't include administrative MTU increase
2239 update PMTU increase is a MUST. (i.e. jumbo frame)
2240 */
2241 /*
2242 If new MTU is less than route PMTU, this new MTU will be the
2243 lowest MTU in the path, update the route PMTU to reflect PMTU
2244 decreases; if new MTU is greater than route PMTU, and the
2245 old MTU is the lowest MTU in the path, update the route PMTU
2246 to reflect the increase. In this case if the other nodes' MTU
2247 also have the lowest MTU, TOO BIG MESSAGE will be lead to
2248 PMTU discouvery.
2249 */
2250 if (rt->dst.dev == arg->dev &&
2251 !dst_metric_locked(&rt->dst, RTAX_MTU) &&
2252 (dst_mtu(&rt->dst) >= arg->mtu ||
2253 (dst_mtu(&rt->dst) < arg->mtu &&
2254 dst_mtu(&rt->dst) == idev->cnf.mtu6))) {
2255 dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2256 }
2257 return 0;
2258 }
2259
2260 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2261 {
2262 struct rt6_mtu_change_arg arg = {
2263 .dev = dev,
2264 .mtu = mtu,
2265 };
2266
2267 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg);
2268 }
2269
2270 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2271 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
2272 [RTA_OIF] = { .type = NLA_U32 },
2273 [RTA_IIF] = { .type = NLA_U32 },
2274 [RTA_PRIORITY] = { .type = NLA_U32 },
2275 [RTA_METRICS] = { .type = NLA_NESTED },
2276 };
2277
2278 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2279 struct fib6_config *cfg)
2280 {
2281 struct rtmsg *rtm;
2282 struct nlattr *tb[RTA_MAX+1];
2283 int err;
2284
2285 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2286 if (err < 0)
2287 goto errout;
2288
2289 err = -EINVAL;
2290 rtm = nlmsg_data(nlh);
2291 memset(cfg, 0, sizeof(*cfg));
2292
2293 cfg->fc_table = rtm->rtm_table;
2294 cfg->fc_dst_len = rtm->rtm_dst_len;
2295 cfg->fc_src_len = rtm->rtm_src_len;
2296 cfg->fc_flags = RTF_UP;
2297 cfg->fc_protocol = rtm->rtm_protocol;
2298
2299 if (rtm->rtm_type == RTN_UNREACHABLE)
2300 cfg->fc_flags |= RTF_REJECT;
2301
2302 if (rtm->rtm_type == RTN_LOCAL)
2303 cfg->fc_flags |= RTF_LOCAL;
2304
2305 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
2306 cfg->fc_nlinfo.nlh = nlh;
2307 cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2308
2309 if (tb[RTA_GATEWAY]) {
2310 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
2311 cfg->fc_flags |= RTF_GATEWAY;
2312 }
2313
2314 if (tb[RTA_DST]) {
2315 int plen = (rtm->rtm_dst_len + 7) >> 3;
2316
2317 if (nla_len(tb[RTA_DST]) < plen)
2318 goto errout;
2319
2320 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2321 }
2322
2323 if (tb[RTA_SRC]) {
2324 int plen = (rtm->rtm_src_len + 7) >> 3;
2325
2326 if (nla_len(tb[RTA_SRC]) < plen)
2327 goto errout;
2328
2329 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2330 }
2331
2332 if (tb[RTA_PREFSRC])
2333 nla_memcpy(&cfg->fc_prefsrc, tb[RTA_PREFSRC], 16);
2334
2335 if (tb[RTA_OIF])
2336 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2337
2338 if (tb[RTA_PRIORITY])
2339 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2340
2341 if (tb[RTA_METRICS]) {
2342 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2343 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2344 }
2345
2346 if (tb[RTA_TABLE])
2347 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2348
2349 err = 0;
2350 errout:
2351 return err;
2352 }
2353
2354 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2355 {
2356 struct fib6_config cfg;
2357 int err;
2358
2359 err = rtm_to_fib6_config(skb, nlh, &cfg);
2360 if (err < 0)
2361 return err;
2362
2363 return ip6_route_del(&cfg);
2364 }
2365
2366 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2367 {
2368 struct fib6_config cfg;
2369 int err;
2370
2371 err = rtm_to_fib6_config(skb, nlh, &cfg);
2372 if (err < 0)
2373 return err;
2374
2375 return ip6_route_add(&cfg);
2376 }
2377
2378 static inline size_t rt6_nlmsg_size(void)
2379 {
2380 return NLMSG_ALIGN(sizeof(struct rtmsg))
2381 + nla_total_size(16) /* RTA_SRC */
2382 + nla_total_size(16) /* RTA_DST */
2383 + nla_total_size(16) /* RTA_GATEWAY */
2384 + nla_total_size(16) /* RTA_PREFSRC */
2385 + nla_total_size(4) /* RTA_TABLE */
2386 + nla_total_size(4) /* RTA_IIF */
2387 + nla_total_size(4) /* RTA_OIF */
2388 + nla_total_size(4) /* RTA_PRIORITY */
2389 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2390 + nla_total_size(sizeof(struct rta_cacheinfo));
2391 }
2392
2393 static int rt6_fill_node(struct net *net,
2394 struct sk_buff *skb, struct rt6_info *rt,
2395 struct in6_addr *dst, struct in6_addr *src,
2396 int iif, int type, u32 pid, u32 seq,
2397 int prefix, int nowait, unsigned int flags)
2398 {
2399 const struct inet_peer *peer;
2400 struct rtmsg *rtm;
2401 struct nlmsghdr *nlh;
2402 long expires;
2403 u32 table;
2404 struct neighbour *n;
2405 u32 ts, tsage;
2406
2407 if (prefix) { /* user wants prefix routes only */
2408 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2409 /* success since this is not a prefix route */
2410 return 1;
2411 }
2412 }
2413
2414 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2415 if (!nlh)
2416 return -EMSGSIZE;
2417
2418 rtm = nlmsg_data(nlh);
2419 rtm->rtm_family = AF_INET6;
2420 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2421 rtm->rtm_src_len = rt->rt6i_src.plen;
2422 rtm->rtm_tos = 0;
2423 if (rt->rt6i_table)
2424 table = rt->rt6i_table->tb6_id;
2425 else
2426 table = RT6_TABLE_UNSPEC;
2427 rtm->rtm_table = table;
2428 if (nla_put_u32(skb, RTA_TABLE, table))
2429 goto nla_put_failure;
2430 if (rt->rt6i_flags & RTF_REJECT)
2431 rtm->rtm_type = RTN_UNREACHABLE;
2432 else if (rt->rt6i_flags & RTF_LOCAL)
2433 rtm->rtm_type = RTN_LOCAL;
2434 else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
2435 rtm->rtm_type = RTN_LOCAL;
2436 else
2437 rtm->rtm_type = RTN_UNICAST;
2438 rtm->rtm_flags = 0;
2439 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2440 rtm->rtm_protocol = rt->rt6i_protocol;
2441 if (rt->rt6i_flags & RTF_DYNAMIC)
2442 rtm->rtm_protocol = RTPROT_REDIRECT;
2443 else if (rt->rt6i_flags & RTF_ADDRCONF)
2444 rtm->rtm_protocol = RTPROT_KERNEL;
2445 else if (rt->rt6i_flags & RTF_DEFAULT)
2446 rtm->rtm_protocol = RTPROT_RA;
2447
2448 if (rt->rt6i_flags & RTF_CACHE)
2449 rtm->rtm_flags |= RTM_F_CLONED;
2450
2451 if (dst) {
2452 if (nla_put(skb, RTA_DST, 16, dst))
2453 goto nla_put_failure;
2454 rtm->rtm_dst_len = 128;
2455 } else if (rtm->rtm_dst_len)
2456 if (nla_put(skb, RTA_DST, 16, &rt->rt6i_dst.addr))
2457 goto nla_put_failure;
2458 #ifdef CONFIG_IPV6_SUBTREES
2459 if (src) {
2460 if (nla_put(skb, RTA_SRC, 16, src))
2461 goto nla_put_failure;
2462 rtm->rtm_src_len = 128;
2463 } else if (rtm->rtm_src_len &&
2464 nla_put(skb, RTA_SRC, 16, &rt->rt6i_src.addr))
2465 goto nla_put_failure;
2466 #endif
2467 if (iif) {
2468 #ifdef CONFIG_IPV6_MROUTE
2469 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2470 int err = ip6mr_get_route(net, skb, rtm, nowait);
2471 if (err <= 0) {
2472 if (!nowait) {
2473 if (err == 0)
2474 return 0;
2475 goto nla_put_failure;
2476 } else {
2477 if (err == -EMSGSIZE)
2478 goto nla_put_failure;
2479 }
2480 }
2481 } else
2482 #endif
2483 if (nla_put_u32(skb, RTA_IIF, iif))
2484 goto nla_put_failure;
2485 } else if (dst) {
2486 struct in6_addr saddr_buf;
2487 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
2488 nla_put(skb, RTA_PREFSRC, 16, &saddr_buf))
2489 goto nla_put_failure;
2490 }
2491
2492 if (rt->rt6i_prefsrc.plen) {
2493 struct in6_addr saddr_buf;
2494 saddr_buf = rt->rt6i_prefsrc.addr;
2495 if (nla_put(skb, RTA_PREFSRC, 16, &saddr_buf))
2496 goto nla_put_failure;
2497 }
2498
2499 if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
2500 goto nla_put_failure;
2501
2502 rcu_read_lock();
2503 n = dst_get_neighbour_noref(&rt->dst);
2504 if (n) {
2505 if (nla_put(skb, RTA_GATEWAY, 16, &n->primary_key) < 0) {
2506 rcu_read_unlock();
2507 goto nla_put_failure;
2508 }
2509 }
2510 rcu_read_unlock();
2511
2512 if (rt->dst.dev &&
2513 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2514 goto nla_put_failure;
2515 if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
2516 goto nla_put_failure;
2517 if (!(rt->rt6i_flags & RTF_EXPIRES))
2518 expires = 0;
2519 else if (rt->dst.expires - jiffies < INT_MAX)
2520 expires = rt->dst.expires - jiffies;
2521 else
2522 expires = INT_MAX;
2523
2524 peer = rt->rt6i_peer;
2525 ts = tsage = 0;
2526 if (peer && peer->tcp_ts_stamp) {
2527 ts = peer->tcp_ts;
2528 tsage = get_seconds() - peer->tcp_ts_stamp;
2529 }
2530
2531 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, ts, tsage,
2532 expires, rt->dst.error) < 0)
2533 goto nla_put_failure;
2534
2535 return nlmsg_end(skb, nlh);
2536
2537 nla_put_failure:
2538 nlmsg_cancel(skb, nlh);
2539 return -EMSGSIZE;
2540 }
2541
2542 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2543 {
2544 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2545 int prefix;
2546
2547 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2548 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2549 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2550 } else
2551 prefix = 0;
2552
2553 return rt6_fill_node(arg->net,
2554 arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2555 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2556 prefix, 0, NLM_F_MULTI);
2557 }
2558
2559 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2560 {
2561 struct net *net = sock_net(in_skb->sk);
2562 struct nlattr *tb[RTA_MAX+1];
2563 struct rt6_info *rt;
2564 struct sk_buff *skb;
2565 struct rtmsg *rtm;
2566 struct flowi6 fl6;
2567 int err, iif = 0, oif = 0;
2568
2569 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2570 if (err < 0)
2571 goto errout;
2572
2573 err = -EINVAL;
2574 memset(&fl6, 0, sizeof(fl6));
2575
2576 if (tb[RTA_SRC]) {
2577 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2578 goto errout;
2579
2580 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
2581 }
2582
2583 if (tb[RTA_DST]) {
2584 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2585 goto errout;
2586
2587 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
2588 }
2589
2590 if (tb[RTA_IIF])
2591 iif = nla_get_u32(tb[RTA_IIF]);
2592
2593 if (tb[RTA_OIF])
2594 oif = nla_get_u32(tb[RTA_OIF]);
2595
2596 if (iif) {
2597 struct net_device *dev;
2598 int flags = 0;
2599
2600 dev = __dev_get_by_index(net, iif);
2601 if (!dev) {
2602 err = -ENODEV;
2603 goto errout;
2604 }
2605
2606 fl6.flowi6_iif = iif;
2607
2608 if (!ipv6_addr_any(&fl6.saddr))
2609 flags |= RT6_LOOKUP_F_HAS_SADDR;
2610
2611 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
2612 flags);
2613 } else {
2614 fl6.flowi6_oif = oif;
2615
2616 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
2617 }
2618
2619 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2620 if (!skb) {
2621 dst_release(&rt->dst);
2622 err = -ENOBUFS;
2623 goto errout;
2624 }
2625
2626 /* Reserve room for dummy headers, this skb can pass
2627 through good chunk of routing engine.
2628 */
2629 skb_reset_mac_header(skb);
2630 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2631
2632 skb_dst_set(skb, &rt->dst);
2633
2634 err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
2635 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2636 nlh->nlmsg_seq, 0, 0, 0);
2637 if (err < 0) {
2638 kfree_skb(skb);
2639 goto errout;
2640 }
2641
2642 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2643 errout:
2644 return err;
2645 }
2646
2647 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2648 {
2649 struct sk_buff *skb;
2650 struct net *net = info->nl_net;
2651 u32 seq;
2652 int err;
2653
2654 err = -ENOBUFS;
2655 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
2656
2657 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2658 if (!skb)
2659 goto errout;
2660
2661 err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
2662 event, info->pid, seq, 0, 0, 0);
2663 if (err < 0) {
2664 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2665 WARN_ON(err == -EMSGSIZE);
2666 kfree_skb(skb);
2667 goto errout;
2668 }
2669 rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE,
2670 info->nlh, gfp_any());
2671 return;
2672 errout:
2673 if (err < 0)
2674 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
2675 }
2676
2677 static int ip6_route_dev_notify(struct notifier_block *this,
2678 unsigned long event, void *data)
2679 {
2680 struct net_device *dev = (struct net_device *)data;
2681 struct net *net = dev_net(dev);
2682
2683 if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
2684 net->ipv6.ip6_null_entry->dst.dev = dev;
2685 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
2686 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2687 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
2688 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
2689 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
2690 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
2691 #endif
2692 }
2693
2694 return NOTIFY_OK;
2695 }
2696
2697 /*
2698 * /proc
2699 */
2700
2701 #ifdef CONFIG_PROC_FS
2702
2703 struct rt6_proc_arg
2704 {
2705 char *buffer;
2706 int offset;
2707 int length;
2708 int skip;
2709 int len;
2710 };
2711
2712 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2713 {
2714 struct seq_file *m = p_arg;
2715 struct neighbour *n;
2716
2717 seq_printf(m, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
2718
2719 #ifdef CONFIG_IPV6_SUBTREES
2720 seq_printf(m, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
2721 #else
2722 seq_puts(m, "00000000000000000000000000000000 00 ");
2723 #endif
2724 rcu_read_lock();
2725 n = dst_get_neighbour_noref(&rt->dst);
2726 if (n) {
2727 seq_printf(m, "%pi6", n->primary_key);
2728 } else {
2729 seq_puts(m, "00000000000000000000000000000000");
2730 }
2731 rcu_read_unlock();
2732 seq_printf(m, " %08x %08x %08x %08x %8s\n",
2733 rt->rt6i_metric, atomic_read(&rt->dst.__refcnt),
2734 rt->dst.__use, rt->rt6i_flags,
2735 rt->dst.dev ? rt->dst.dev->name : "");
2736 return 0;
2737 }
2738
2739 static int ipv6_route_show(struct seq_file *m, void *v)
2740 {
2741 struct net *net = (struct net *)m->private;
2742 fib6_clean_all_ro(net, rt6_info_route, 0, m);
2743 return 0;
2744 }
2745
2746 static int ipv6_route_open(struct inode *inode, struct file *file)
2747 {
2748 return single_open_net(inode, file, ipv6_route_show);
2749 }
2750
2751 static const struct file_operations ipv6_route_proc_fops = {
2752 .owner = THIS_MODULE,
2753 .open = ipv6_route_open,
2754 .read = seq_read,
2755 .llseek = seq_lseek,
2756 .release = single_release_net,
2757 };
2758
2759 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2760 {
2761 struct net *net = (struct net *)seq->private;
2762 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2763 net->ipv6.rt6_stats->fib_nodes,
2764 net->ipv6.rt6_stats->fib_route_nodes,
2765 net->ipv6.rt6_stats->fib_rt_alloc,
2766 net->ipv6.rt6_stats->fib_rt_entries,
2767 net->ipv6.rt6_stats->fib_rt_cache,
2768 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
2769 net->ipv6.rt6_stats->fib_discarded_routes);
2770
2771 return 0;
2772 }
2773
2774 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2775 {
2776 return single_open_net(inode, file, rt6_stats_seq_show);
2777 }
2778
2779 static const struct file_operations rt6_stats_seq_fops = {
2780 .owner = THIS_MODULE,
2781 .open = rt6_stats_seq_open,
2782 .read = seq_read,
2783 .llseek = seq_lseek,
2784 .release = single_release_net,
2785 };
2786 #endif /* CONFIG_PROC_FS */
2787
2788 #ifdef CONFIG_SYSCTL
2789
2790 static
2791 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write,
2792 void __user *buffer, size_t *lenp, loff_t *ppos)
2793 {
2794 struct net *net;
2795 int delay;
2796 if (!write)
2797 return -EINVAL;
2798
2799 net = (struct net *)ctl->extra1;
2800 delay = net->ipv6.sysctl.flush_delay;
2801 proc_dointvec(ctl, write, buffer, lenp, ppos);
2802 fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net);
2803 return 0;
2804 }
2805
2806 ctl_table ipv6_route_table_template[] = {
2807 {
2808 .procname = "flush",
2809 .data = &init_net.ipv6.sysctl.flush_delay,
2810 .maxlen = sizeof(int),
2811 .mode = 0200,
2812 .proc_handler = ipv6_sysctl_rtcache_flush
2813 },
2814 {
2815 .procname = "gc_thresh",
2816 .data = &ip6_dst_ops_template.gc_thresh,
2817 .maxlen = sizeof(int),
2818 .mode = 0644,
2819 .proc_handler = proc_dointvec,
2820 },
2821 {
2822 .procname = "max_size",
2823 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
2824 .maxlen = sizeof(int),
2825 .mode = 0644,
2826 .proc_handler = proc_dointvec,
2827 },
2828 {
2829 .procname = "gc_min_interval",
2830 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2831 .maxlen = sizeof(int),
2832 .mode = 0644,
2833 .proc_handler = proc_dointvec_jiffies,
2834 },
2835 {
2836 .procname = "gc_timeout",
2837 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
2838 .maxlen = sizeof(int),
2839 .mode = 0644,
2840 .proc_handler = proc_dointvec_jiffies,
2841 },
2842 {
2843 .procname = "gc_interval",
2844 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
2845 .maxlen = sizeof(int),
2846 .mode = 0644,
2847 .proc_handler = proc_dointvec_jiffies,
2848 },
2849 {
2850 .procname = "gc_elasticity",
2851 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
2852 .maxlen = sizeof(int),
2853 .mode = 0644,
2854 .proc_handler = proc_dointvec,
2855 },
2856 {
2857 .procname = "mtu_expires",
2858 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
2859 .maxlen = sizeof(int),
2860 .mode = 0644,
2861 .proc_handler = proc_dointvec_jiffies,
2862 },
2863 {
2864 .procname = "min_adv_mss",
2865 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
2866 .maxlen = sizeof(int),
2867 .mode = 0644,
2868 .proc_handler = proc_dointvec,
2869 },
2870 {
2871 .procname = "gc_min_interval_ms",
2872 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2873 .maxlen = sizeof(int),
2874 .mode = 0644,
2875 .proc_handler = proc_dointvec_ms_jiffies,
2876 },
2877 { }
2878 };
2879
2880 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
2881 {
2882 struct ctl_table *table;
2883
2884 table = kmemdup(ipv6_route_table_template,
2885 sizeof(ipv6_route_table_template),
2886 GFP_KERNEL);
2887
2888 if (table) {
2889 table[0].data = &net->ipv6.sysctl.flush_delay;
2890 table[0].extra1 = net;
2891 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
2892 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
2893 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2894 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
2895 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
2896 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
2897 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
2898 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
2899 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2900 }
2901
2902 return table;
2903 }
2904 #endif
2905
2906 static int __net_init ip6_route_net_init(struct net *net)
2907 {
2908 int ret = -ENOMEM;
2909
2910 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
2911 sizeof(net->ipv6.ip6_dst_ops));
2912
2913 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
2914 goto out_ip6_dst_ops;
2915
2916 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
2917 sizeof(*net->ipv6.ip6_null_entry),
2918 GFP_KERNEL);
2919 if (!net->ipv6.ip6_null_entry)
2920 goto out_ip6_dst_entries;
2921 net->ipv6.ip6_null_entry->dst.path =
2922 (struct dst_entry *)net->ipv6.ip6_null_entry;
2923 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2924 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
2925 ip6_template_metrics, true);
2926
2927 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2928 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
2929 sizeof(*net->ipv6.ip6_prohibit_entry),
2930 GFP_KERNEL);
2931 if (!net->ipv6.ip6_prohibit_entry)
2932 goto out_ip6_null_entry;
2933 net->ipv6.ip6_prohibit_entry->dst.path =
2934 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
2935 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2936 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
2937 ip6_template_metrics, true);
2938
2939 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
2940 sizeof(*net->ipv6.ip6_blk_hole_entry),
2941 GFP_KERNEL);
2942 if (!net->ipv6.ip6_blk_hole_entry)
2943 goto out_ip6_prohibit_entry;
2944 net->ipv6.ip6_blk_hole_entry->dst.path =
2945 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
2946 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2947 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
2948 ip6_template_metrics, true);
2949 #endif
2950
2951 net->ipv6.sysctl.flush_delay = 0;
2952 net->ipv6.sysctl.ip6_rt_max_size = 4096;
2953 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
2954 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
2955 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
2956 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
2957 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
2958 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
2959
2960 #ifdef CONFIG_PROC_FS
2961 proc_net_fops_create(net, "ipv6_route", 0, &ipv6_route_proc_fops);
2962 proc_net_fops_create(net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2963 #endif
2964 net->ipv6.ip6_rt_gc_expire = 30*HZ;
2965
2966 ret = 0;
2967 out:
2968 return ret;
2969
2970 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2971 out_ip6_prohibit_entry:
2972 kfree(net->ipv6.ip6_prohibit_entry);
2973 out_ip6_null_entry:
2974 kfree(net->ipv6.ip6_null_entry);
2975 #endif
2976 out_ip6_dst_entries:
2977 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2978 out_ip6_dst_ops:
2979 goto out;
2980 }
2981
2982 static void __net_exit ip6_route_net_exit(struct net *net)
2983 {
2984 #ifdef CONFIG_PROC_FS
2985 proc_net_remove(net, "ipv6_route");
2986 proc_net_remove(net, "rt6_stats");
2987 #endif
2988 kfree(net->ipv6.ip6_null_entry);
2989 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2990 kfree(net->ipv6.ip6_prohibit_entry);
2991 kfree(net->ipv6.ip6_blk_hole_entry);
2992 #endif
2993 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2994 }
2995
2996 static struct pernet_operations ip6_route_net_ops = {
2997 .init = ip6_route_net_init,
2998 .exit = ip6_route_net_exit,
2999 };
3000
3001 static struct notifier_block ip6_route_dev_notifier = {
3002 .notifier_call = ip6_route_dev_notify,
3003 .priority = 0,
3004 };
3005
3006 int __init ip6_route_init(void)
3007 {
3008 int ret;
3009
3010 ret = -ENOMEM;
3011 ip6_dst_ops_template.kmem_cachep =
3012 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3013 SLAB_HWCACHE_ALIGN, NULL);
3014 if (!ip6_dst_ops_template.kmem_cachep)
3015 goto out;
3016
3017 ret = dst_entries_init(&ip6_dst_blackhole_ops);
3018 if (ret)
3019 goto out_kmem_cache;
3020
3021 ret = register_pernet_subsys(&ip6_route_net_ops);
3022 if (ret)
3023 goto out_dst_entries;
3024
3025 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3026
3027 /* Registering of the loopback is done before this portion of code,
3028 * the loopback reference in rt6_info will not be taken, do it
3029 * manually for init_net */
3030 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3031 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3032 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3033 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3034 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3035 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3036 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3037 #endif
3038 ret = fib6_init();
3039 if (ret)
3040 goto out_register_subsys;
3041
3042 ret = xfrm6_init();
3043 if (ret)
3044 goto out_fib6_init;
3045
3046 ret = fib6_rules_init();
3047 if (ret)
3048 goto xfrm6_init;
3049
3050 ret = -ENOBUFS;
3051 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3052 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3053 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3054 goto fib6_rules_init;
3055
3056 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3057 if (ret)
3058 goto fib6_rules_init;
3059
3060 out:
3061 return ret;
3062
3063 fib6_rules_init:
3064 fib6_rules_cleanup();
3065 xfrm6_init:
3066 xfrm6_fini();
3067 out_fib6_init:
3068 fib6_gc_cleanup();
3069 out_register_subsys:
3070 unregister_pernet_subsys(&ip6_route_net_ops);
3071 out_dst_entries:
3072 dst_entries_destroy(&ip6_dst_blackhole_ops);
3073 out_kmem_cache:
3074 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3075 goto out;
3076 }
3077
3078 void ip6_route_cleanup(void)
3079 {
3080 unregister_netdevice_notifier(&ip6_route_dev_notifier);
3081 fib6_rules_cleanup();
3082 xfrm6_fini();
3083 fib6_gc_cleanup();
3084 unregister_pernet_subsys(&ip6_route_net_ops);
3085 dst_entries_destroy(&ip6_dst_blackhole_ops);
3086 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3087 }
Linux kernel - Deliverables
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