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soc: qcom: llcc: Name regmaps to avoid collisions
[linux/fpc-iii.git] / net / ipv6 / route.c
bloba63ff85fe14198fc23a5cbc7abcd107df5df00c8
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux INET6 implementation
4 * FIB front-end.
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 */
9
10 /* Changes:
11 *
12 * YOSHIFUJI Hideaki @USAGI
13 * reworked default router selection.
14 * - respect outgoing interface
15 * - select from (probably) reachable routers (i.e.
16 * routers in REACHABLE, STALE, DELAY or PROBE states).
17 * - always select the same router if it is (probably)
18 * reachable. otherwise, round-robin the list.
19 * Ville Nuorvala
20 * Fixed routing subtrees.
21 */
22
23 #define pr_fmt(fmt) "IPv6: " fmt
24
25 #include <linux/capability.h>
26 #include <linux/errno.h>
27 #include <linux/export.h>
28 #include <linux/types.h>
29 #include <linux/times.h>
30 #include <linux/socket.h>
31 #include <linux/sockios.h>
32 #include <linux/net.h>
33 #include <linux/route.h>
34 #include <linux/netdevice.h>
35 #include <linux/in6.h>
36 #include <linux/mroute6.h>
37 #include <linux/init.h>
38 #include <linux/if_arp.h>
39 #include <linux/proc_fs.h>
40 #include <linux/seq_file.h>
41 #include <linux/nsproxy.h>
42 #include <linux/slab.h>
43 #include <linux/jhash.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/dst_metadata.h>
55 #include <net/xfrm.h>
56 #include <net/netevent.h>
57 #include <net/netlink.h>
58 #include <net/rtnh.h>
59 #include <net/lwtunnel.h>
60 #include <net/ip_tunnels.h>
61 #include <net/l3mdev.h>
62 #include <net/ip.h>
63 #include <linux/uaccess.h>
64
65 #ifdef CONFIG_SYSCTL
66 #include <linux/sysctl.h>
67 #endif
68
69 static int ip6_rt_type_to_error(u8 fib6_type);
70
71 #define CREATE_TRACE_POINTS
72 #include <trace/events/fib6.h>
73 EXPORT_TRACEPOINT_SYMBOL_GPL(fib6_table_lookup);
74 #undef CREATE_TRACE_POINTS
75
76 enum rt6_nud_state {
77 RT6_NUD_FAIL_HARD = -3,
78 RT6_NUD_FAIL_PROBE = -2,
79 RT6_NUD_FAIL_DO_RR = -1,
80 RT6_NUD_SUCCEED = 1
81 };
82
83 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
84 static unsigned int ip6_default_advmss(const struct dst_entry *dst);
85 static unsigned int ip6_mtu(const struct dst_entry *dst);
86 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
87 static void ip6_dst_destroy(struct dst_entry *);
88 static void ip6_dst_ifdown(struct dst_entry *,
89 struct net_device *dev, int how);
90 static int ip6_dst_gc(struct dst_ops *ops);
91
92 static int ip6_pkt_discard(struct sk_buff *skb);
93 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
94 static int ip6_pkt_prohibit(struct sk_buff *skb);
95 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
96 static void ip6_link_failure(struct sk_buff *skb);
97 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
98 struct sk_buff *skb, u32 mtu);
99 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
100 struct sk_buff *skb);
101 static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
102 int strict);
103 static size_t rt6_nlmsg_size(struct fib6_info *f6i);
104 static int rt6_fill_node(struct net *net, struct sk_buff *skb,
105 struct fib6_info *rt, struct dst_entry *dst,
106 struct in6_addr *dest, struct in6_addr *src,
107 int iif, int type, u32 portid, u32 seq,
108 unsigned int flags);
109 static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res,
110 const struct in6_addr *daddr,
111 const struct in6_addr *saddr);
112
113 #ifdef CONFIG_IPV6_ROUTE_INFO
114 static struct fib6_info *rt6_add_route_info(struct net *net,
115 const struct in6_addr *prefix, int prefixlen,
116 const struct in6_addr *gwaddr,
117 struct net_device *dev,
118 unsigned int pref);
119 static struct fib6_info *rt6_get_route_info(struct net *net,
120 const struct in6_addr *prefix, int prefixlen,
121 const struct in6_addr *gwaddr,
122 struct net_device *dev);
123 #endif
124
125 struct uncached_list {
126 spinlock_t lock;
127 struct list_head head;
128 };
129
130 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
131
132 void rt6_uncached_list_add(struct rt6_info *rt)
133 {
134 struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
135
136 rt->rt6i_uncached_list = ul;
137
138 spin_lock_bh(&ul->lock);
139 list_add_tail(&rt->rt6i_uncached, &ul->head);
140 spin_unlock_bh(&ul->lock);
141 }
142
143 void rt6_uncached_list_del(struct rt6_info *rt)
144 {
145 if (!list_empty(&rt->rt6i_uncached)) {
146 struct uncached_list *ul = rt->rt6i_uncached_list;
147 struct net *net = dev_net(rt->dst.dev);
148
149 spin_lock_bh(&ul->lock);
150 list_del(&rt->rt6i_uncached);
151 atomic_dec(&net->ipv6.rt6_stats->fib_rt_uncache);
152 spin_unlock_bh(&ul->lock);
153 }
154 }
155
156 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
157 {
158 struct net_device *loopback_dev = net->loopback_dev;
159 int cpu;
160
161 if (dev == loopback_dev)
162 return;
163
164 for_each_possible_cpu(cpu) {
165 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
166 struct rt6_info *rt;
167
168 spin_lock_bh(&ul->lock);
169 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
170 struct inet6_dev *rt_idev = rt->rt6i_idev;
171 struct net_device *rt_dev = rt->dst.dev;
172
173 if (rt_idev->dev == dev) {
174 rt->rt6i_idev = in6_dev_get(loopback_dev);
175 in6_dev_put(rt_idev);
176 }
177
178 if (rt_dev == dev) {
179 rt->dst.dev = blackhole_netdev;
180 dev_hold(rt->dst.dev);
181 dev_put(rt_dev);
182 }
183 }
184 spin_unlock_bh(&ul->lock);
185 }
186 }
187
188 static inline const void *choose_neigh_daddr(const struct in6_addr *p,
189 struct sk_buff *skb,
190 const void *daddr)
191 {
192 if (!ipv6_addr_any(p))
193 return (const void *) p;
194 else if (skb)
195 return &ipv6_hdr(skb)->daddr;
196 return daddr;
197 }
198
199 struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
200 struct net_device *dev,
201 struct sk_buff *skb,
202 const void *daddr)
203 {
204 struct neighbour *n;
205
206 daddr = choose_neigh_daddr(gw, skb, daddr);
207 n = __ipv6_neigh_lookup(dev, daddr);
208 if (n)
209 return n;
210
211 n = neigh_create(&nd_tbl, daddr, dev);
212 return IS_ERR(n) ? NULL : n;
213 }
214
215 static struct neighbour *ip6_dst_neigh_lookup(const struct dst_entry *dst,
216 struct sk_buff *skb,
217 const void *daddr)
218 {
219 const struct rt6_info *rt = container_of(dst, struct rt6_info, dst);
220
221 return ip6_neigh_lookup(rt6_nexthop(rt, &in6addr_any),
222 dst->dev, skb, daddr);
223 }
224
225 static void ip6_confirm_neigh(const struct dst_entry *dst, const void *daddr)
226 {
227 struct net_device *dev = dst->dev;
228 struct rt6_info *rt = (struct rt6_info *)dst;
229
230 daddr = choose_neigh_daddr(rt6_nexthop(rt, &in6addr_any), NULL, daddr);
231 if (!daddr)
232 return;
233 if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
234 return;
235 if (ipv6_addr_is_multicast((const struct in6_addr *)daddr))
236 return;
237 __ipv6_confirm_neigh(dev, daddr);
238 }
239
240 static struct dst_ops ip6_dst_ops_template = {
241 .family = AF_INET6,
242 .gc = ip6_dst_gc,
243 .gc_thresh = 1024,
244 .check = ip6_dst_check,
245 .default_advmss = ip6_default_advmss,
246 .mtu = ip6_mtu,
247 .cow_metrics = dst_cow_metrics_generic,
248 .destroy = ip6_dst_destroy,
249 .ifdown = ip6_dst_ifdown,
250 .negative_advice = ip6_negative_advice,
251 .link_failure = ip6_link_failure,
252 .update_pmtu = ip6_rt_update_pmtu,
253 .redirect = rt6_do_redirect,
254 .local_out = __ip6_local_out,
255 .neigh_lookup = ip6_dst_neigh_lookup,
256 .confirm_neigh = ip6_confirm_neigh,
257 };
258
259 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
260 {
261 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
262
263 return mtu ? : dst->dev->mtu;
264 }
265
266 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
267 struct sk_buff *skb, u32 mtu)
268 {
269 }
270
271 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
272 struct sk_buff *skb)
273 {
274 }
275
276 static struct dst_ops ip6_dst_blackhole_ops = {
277 .family = AF_INET6,
278 .destroy = ip6_dst_destroy,
279 .check = ip6_dst_check,
280 .mtu = ip6_blackhole_mtu,
281 .default_advmss = ip6_default_advmss,
282 .update_pmtu = ip6_rt_blackhole_update_pmtu,
283 .redirect = ip6_rt_blackhole_redirect,
284 .cow_metrics = dst_cow_metrics_generic,
285 .neigh_lookup = ip6_dst_neigh_lookup,
286 };
287
288 static const u32 ip6_template_metrics[RTAX_MAX] = {
289 [RTAX_HOPLIMIT - 1] = 0,
290 };
291
292 static const struct fib6_info fib6_null_entry_template = {
293 .fib6_flags = (RTF_REJECT | RTF_NONEXTHOP),
294 .fib6_protocol = RTPROT_KERNEL,
295 .fib6_metric = ~(u32)0,
296 .fib6_ref = REFCOUNT_INIT(1),
297 .fib6_type = RTN_UNREACHABLE,
298 .fib6_metrics = (struct dst_metrics *)&dst_default_metrics,
299 };
300
301 static const struct rt6_info ip6_null_entry_template = {
302 .dst = {
303 .__refcnt = ATOMIC_INIT(1),
304 .__use = 1,
305 .obsolete = DST_OBSOLETE_FORCE_CHK,
306 .error = -ENETUNREACH,
307 .input = ip6_pkt_discard,
308 .output = ip6_pkt_discard_out,
309 },
310 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
311 };
312
313 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
314
315 static const struct rt6_info ip6_prohibit_entry_template = {
316 .dst = {
317 .__refcnt = ATOMIC_INIT(1),
318 .__use = 1,
319 .obsolete = DST_OBSOLETE_FORCE_CHK,
320 .error = -EACCES,
321 .input = ip6_pkt_prohibit,
322 .output = ip6_pkt_prohibit_out,
323 },
324 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
325 };
326
327 static const struct rt6_info ip6_blk_hole_entry_template = {
328 .dst = {
329 .__refcnt = ATOMIC_INIT(1),
330 .__use = 1,
331 .obsolete = DST_OBSOLETE_FORCE_CHK,
332 .error = -EINVAL,
333 .input = dst_discard,
334 .output = dst_discard_out,
335 },
336 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
337 };
338
339 #endif
340
341 static void rt6_info_init(struct rt6_info *rt)
342 {
343 struct dst_entry *dst = &rt->dst;
344
345 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
346 INIT_LIST_HEAD(&rt->rt6i_uncached);
347 }
348
349 /* allocate dst with ip6_dst_ops */
350 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
351 int flags)
352 {
353 struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
354 1, DST_OBSOLETE_FORCE_CHK, flags);
355
356 if (rt) {
357 rt6_info_init(rt);
358 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
359 }
360
361 return rt;
362 }
363 EXPORT_SYMBOL(ip6_dst_alloc);
364
365 static void ip6_dst_destroy(struct dst_entry *dst)
366 {
367 struct rt6_info *rt = (struct rt6_info *)dst;
368 struct fib6_info *from;
369 struct inet6_dev *idev;
370
371 ip_dst_metrics_put(dst);
372 rt6_uncached_list_del(rt);
373
374 idev = rt->rt6i_idev;
375 if (idev) {
376 rt->rt6i_idev = NULL;
377 in6_dev_put(idev);
378 }
379
380 from = xchg((__force struct fib6_info **)&rt->from, NULL);
381 fib6_info_release(from);
382 }
383
384 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
385 int how)
386 {
387 struct rt6_info *rt = (struct rt6_info *)dst;
388 struct inet6_dev *idev = rt->rt6i_idev;
389 struct net_device *loopback_dev =
390 dev_net(dev)->loopback_dev;
391
392 if (idev && idev->dev != loopback_dev) {
393 struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
394 if (loopback_idev) {
395 rt->rt6i_idev = loopback_idev;
396 in6_dev_put(idev);
397 }
398 }
399 }
400
401 static bool __rt6_check_expired(const struct rt6_info *rt)
402 {
403 if (rt->rt6i_flags & RTF_EXPIRES)
404 return time_after(jiffies, rt->dst.expires);
405 else
406 return false;
407 }
408
409 static bool rt6_check_expired(const struct rt6_info *rt)
410 {
411 struct fib6_info *from;
412
413 from = rcu_dereference(rt->from);
414
415 if (rt->rt6i_flags & RTF_EXPIRES) {
416 if (time_after(jiffies, rt->dst.expires))
417 return true;
418 } else if (from) {
419 return rt->dst.obsolete != DST_OBSOLETE_FORCE_CHK ||
420 fib6_check_expired(from);
421 }
422 return false;
423 }
424
425 void fib6_select_path(const struct net *net, struct fib6_result *res,
426 struct flowi6 *fl6, int oif, bool have_oif_match,
427 const struct sk_buff *skb, int strict)
428 {
429 struct fib6_info *sibling, *next_sibling;
430 struct fib6_info *match = res->f6i;
431
432 if ((!match->fib6_nsiblings && !match->nh) || have_oif_match)
433 goto out;
434
435 /* We might have already computed the hash for ICMPv6 errors. In such
436 * case it will always be non-zero. Otherwise now is the time to do it.
437 */
438 if (!fl6->mp_hash &&
439 (!match->nh || nexthop_is_multipath(match->nh)))
440 fl6->mp_hash = rt6_multipath_hash(net, fl6, skb, NULL);
441
442 if (unlikely(match->nh)) {
443 nexthop_path_fib6_result(res, fl6->mp_hash);
444 return;
445 }
446
447 if (fl6->mp_hash <= atomic_read(&match->fib6_nh->fib_nh_upper_bound))
448 goto out;
449
450 list_for_each_entry_safe(sibling, next_sibling, &match->fib6_siblings,
451 fib6_siblings) {
452 const struct fib6_nh *nh = sibling->fib6_nh;
453 int nh_upper_bound;
454
455 nh_upper_bound = atomic_read(&nh->fib_nh_upper_bound);
456 if (fl6->mp_hash > nh_upper_bound)
457 continue;
458 if (rt6_score_route(nh, sibling->fib6_flags, oif, strict) < 0)
459 break;
460 match = sibling;
461 break;
462 }
463
464 out:
465 res->f6i = match;
466 res->nh = match->fib6_nh;
467 }
468
469 /*
470 * Route lookup. rcu_read_lock() should be held.
471 */
472
473 static bool __rt6_device_match(struct net *net, const struct fib6_nh *nh,
474 const struct in6_addr *saddr, int oif, int flags)
475 {
476 const struct net_device *dev;
477
478 if (nh->fib_nh_flags & RTNH_F_DEAD)
479 return false;
480
481 dev = nh->fib_nh_dev;
482 if (oif) {
483 if (dev->ifindex == oif)
484 return true;
485 } else {
486 if (ipv6_chk_addr(net, saddr, dev,
487 flags & RT6_LOOKUP_F_IFACE))
488 return true;
489 }
490
491 return false;
492 }
493
494 struct fib6_nh_dm_arg {
495 struct net *net;
496 const struct in6_addr *saddr;
497 int oif;
498 int flags;
499 struct fib6_nh *nh;
500 };
501
502 static int __rt6_nh_dev_match(struct fib6_nh *nh, void *_arg)
503 {
504 struct fib6_nh_dm_arg *arg = _arg;
505
506 arg->nh = nh;
507 return __rt6_device_match(arg->net, nh, arg->saddr, arg->oif,
508 arg->flags);
509 }
510
511 /* returns fib6_nh from nexthop or NULL */
512 static struct fib6_nh *rt6_nh_dev_match(struct net *net, struct nexthop *nh,
513 struct fib6_result *res,
514 const struct in6_addr *saddr,
515 int oif, int flags)
516 {
517 struct fib6_nh_dm_arg arg = {
518 .net = net,
519 .saddr = saddr,
520 .oif = oif,
521 .flags = flags,
522 };
523
524 if (nexthop_is_blackhole(nh))
525 return NULL;
526
527 if (nexthop_for_each_fib6_nh(nh, __rt6_nh_dev_match, &arg))
528 return arg.nh;
529
530 return NULL;
531 }
532
533 static void rt6_device_match(struct net *net, struct fib6_result *res,
534 const struct in6_addr *saddr, int oif, int flags)
535 {
536 struct fib6_info *f6i = res->f6i;
537 struct fib6_info *spf6i;
538 struct fib6_nh *nh;
539
540 if (!oif && ipv6_addr_any(saddr)) {
541 if (unlikely(f6i->nh)) {
542 nh = nexthop_fib6_nh(f6i->nh);
543 if (nexthop_is_blackhole(f6i->nh))
544 goto out_blackhole;
545 } else {
546 nh = f6i->fib6_nh;
547 }
548 if (!(nh->fib_nh_flags & RTNH_F_DEAD))
549 goto out;
550 }
551
552 for (spf6i = f6i; spf6i; spf6i = rcu_dereference(spf6i->fib6_next)) {
553 bool matched = false;
554
555 if (unlikely(spf6i->nh)) {
556 nh = rt6_nh_dev_match(net, spf6i->nh, res, saddr,
557 oif, flags);
558 if (nh)
559 matched = true;
560 } else {
561 nh = spf6i->fib6_nh;
562 if (__rt6_device_match(net, nh, saddr, oif, flags))
563 matched = true;
564 }
565 if (matched) {
566 res->f6i = spf6i;
567 goto out;
568 }
569 }
570
571 if (oif && flags & RT6_LOOKUP_F_IFACE) {
572 res->f6i = net->ipv6.fib6_null_entry;
573 nh = res->f6i->fib6_nh;
574 goto out;
575 }
576
577 if (unlikely(f6i->nh)) {
578 nh = nexthop_fib6_nh(f6i->nh);
579 if (nexthop_is_blackhole(f6i->nh))
580 goto out_blackhole;
581 } else {
582 nh = f6i->fib6_nh;
583 }
584
585 if (nh->fib_nh_flags & RTNH_F_DEAD) {
586 res->f6i = net->ipv6.fib6_null_entry;
587 nh = res->f6i->fib6_nh;
588 }
589 out:
590 res->nh = nh;
591 res->fib6_type = res->f6i->fib6_type;
592 res->fib6_flags = res->f6i->fib6_flags;
593 return;
594
595 out_blackhole:
596 res->fib6_flags |= RTF_REJECT;
597 res->fib6_type = RTN_BLACKHOLE;
598 res->nh = nh;
599 }
600
601 #ifdef CONFIG_IPV6_ROUTER_PREF
602 struct __rt6_probe_work {
603 struct work_struct work;
604 struct in6_addr target;
605 struct net_device *dev;
606 };
607
608 static void rt6_probe_deferred(struct work_struct *w)
609 {
610 struct in6_addr mcaddr;
611 struct __rt6_probe_work *work =
612 container_of(w, struct __rt6_probe_work, work);
613
614 addrconf_addr_solict_mult(&work->target, &mcaddr);
615 ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0);
616 dev_put(work->dev);
617 kfree(work);
618 }
619
620 static void rt6_probe(struct fib6_nh *fib6_nh)
621 {
622 struct __rt6_probe_work *work = NULL;
623 const struct in6_addr *nh_gw;
624 struct neighbour *neigh;
625 struct net_device *dev;
626 struct inet6_dev *idev;
627
628 /*
629 * Okay, this does not seem to be appropriate
630 * for now, however, we need to check if it
631 * is really so; aka Router Reachability Probing.
632 *
633 * Router Reachability Probe MUST be rate-limited
634 * to no more than one per minute.
635 */
636 if (fib6_nh->fib_nh_gw_family)
637 return;
638
639 nh_gw = &fib6_nh->fib_nh_gw6;
640 dev = fib6_nh->fib_nh_dev;
641 rcu_read_lock_bh();
642 idev = __in6_dev_get(dev);
643 neigh = __ipv6_neigh_lookup_noref(dev, nh_gw);
644 if (neigh) {
645 if (neigh->nud_state & NUD_VALID)
646 goto out;
647
648 write_lock(&neigh->lock);
649 if (!(neigh->nud_state & NUD_VALID) &&
650 time_after(jiffies,
651 neigh->updated + idev->cnf.rtr_probe_interval)) {
652 work = kmalloc(sizeof(*work), GFP_ATOMIC);
653 if (work)
654 __neigh_set_probe_once(neigh);
655 }
656 write_unlock(&neigh->lock);
657 } else if (time_after(jiffies, fib6_nh->last_probe +
658 idev->cnf.rtr_probe_interval)) {
659 work = kmalloc(sizeof(*work), GFP_ATOMIC);
660 }
661
662 if (work) {
663 fib6_nh->last_probe = jiffies;
664 INIT_WORK(&work->work, rt6_probe_deferred);
665 work->target = *nh_gw;
666 dev_hold(dev);
667 work->dev = dev;
668 schedule_work(&work->work);
669 }
670
671 out:
672 rcu_read_unlock_bh();
673 }
674 #else
675 static inline void rt6_probe(struct fib6_nh *fib6_nh)
676 {
677 }
678 #endif
679
680 /*
681 * Default Router Selection (RFC 2461 6.3.6)
682 */
683 static enum rt6_nud_state rt6_check_neigh(const struct fib6_nh *fib6_nh)
684 {
685 enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
686 struct neighbour *neigh;
687
688 rcu_read_lock_bh();
689 neigh = __ipv6_neigh_lookup_noref(fib6_nh->fib_nh_dev,
690 &fib6_nh->fib_nh_gw6);
691 if (neigh) {
692 read_lock(&neigh->lock);
693 if (neigh->nud_state & NUD_VALID)
694 ret = RT6_NUD_SUCCEED;
695 #ifdef CONFIG_IPV6_ROUTER_PREF
696 else if (!(neigh->nud_state & NUD_FAILED))
697 ret = RT6_NUD_SUCCEED;
698 else
699 ret = RT6_NUD_FAIL_PROBE;
700 #endif
701 read_unlock(&neigh->lock);
702 } else {
703 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
704 RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
705 }
706 rcu_read_unlock_bh();
707
708 return ret;
709 }
710
711 static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
712 int strict)
713 {
714 int m = 0;
715
716 if (!oif || nh->fib_nh_dev->ifindex == oif)
717 m = 2;
718
719 if (!m && (strict & RT6_LOOKUP_F_IFACE))
720 return RT6_NUD_FAIL_HARD;
721 #ifdef CONFIG_IPV6_ROUTER_PREF
722 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(fib6_flags)) << 2;
723 #endif
724 if ((strict & RT6_LOOKUP_F_REACHABLE) &&
725 !(fib6_flags & RTF_NONEXTHOP) && nh->fib_nh_gw_family) {
726 int n = rt6_check_neigh(nh);
727 if (n < 0)
728 return n;
729 }
730 return m;
731 }
732
733 static bool find_match(struct fib6_nh *nh, u32 fib6_flags,
734 int oif, int strict, int *mpri, bool *do_rr)
735 {
736 bool match_do_rr = false;
737 bool rc = false;
738 int m;
739
740 if (nh->fib_nh_flags & RTNH_F_DEAD)
741 goto out;
742
743 if (ip6_ignore_linkdown(nh->fib_nh_dev) &&
744 nh->fib_nh_flags & RTNH_F_LINKDOWN &&
745 !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE))
746 goto out;
747
748 m = rt6_score_route(nh, fib6_flags, oif, strict);
749 if (m == RT6_NUD_FAIL_DO_RR) {
750 match_do_rr = true;
751 m = 0; /* lowest valid score */
752 } else if (m == RT6_NUD_FAIL_HARD) {
753 goto out;
754 }
755
756 if (strict & RT6_LOOKUP_F_REACHABLE)
757 rt6_probe(nh);
758
759 /* note that m can be RT6_NUD_FAIL_PROBE at this point */
760 if (m > *mpri) {
761 *do_rr = match_do_rr;
762 *mpri = m;
763 rc = true;
764 }
765 out:
766 return rc;
767 }
768
769 struct fib6_nh_frl_arg {
770 u32 flags;
771 int oif;
772 int strict;
773 int *mpri;
774 bool *do_rr;
775 struct fib6_nh *nh;
776 };
777
778 static int rt6_nh_find_match(struct fib6_nh *nh, void *_arg)
779 {
780 struct fib6_nh_frl_arg *arg = _arg;
781
782 arg->nh = nh;
783 return find_match(nh, arg->flags, arg->oif, arg->strict,
784 arg->mpri, arg->do_rr);
785 }
786
787 static void __find_rr_leaf(struct fib6_info *f6i_start,
788 struct fib6_info *nomatch, u32 metric,
789 struct fib6_result *res, struct fib6_info **cont,
790 int oif, int strict, bool *do_rr, int *mpri)
791 {
792 struct fib6_info *f6i;
793
794 for (f6i = f6i_start;
795 f6i && f6i != nomatch;
796 f6i = rcu_dereference(f6i->fib6_next)) {
797 bool matched = false;
798 struct fib6_nh *nh;
799
800 if (cont && f6i->fib6_metric != metric) {
801 *cont = f6i;
802 return;
803 }
804
805 if (fib6_check_expired(f6i))
806 continue;
807
808 if (unlikely(f6i->nh)) {
809 struct fib6_nh_frl_arg arg = {
810 .flags = f6i->fib6_flags,
811 .oif = oif,
812 .strict = strict,
813 .mpri = mpri,
814 .do_rr = do_rr
815 };
816
817 if (nexthop_is_blackhole(f6i->nh)) {
818 res->fib6_flags = RTF_REJECT;
819 res->fib6_type = RTN_BLACKHOLE;
820 res->f6i = f6i;
821 res->nh = nexthop_fib6_nh(f6i->nh);
822 return;
823 }
824 if (nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_find_match,
825 &arg)) {
826 matched = true;
827 nh = arg.nh;
828 }
829 } else {
830 nh = f6i->fib6_nh;
831 if (find_match(nh, f6i->fib6_flags, oif, strict,
832 mpri, do_rr))
833 matched = true;
834 }
835 if (matched) {
836 res->f6i = f6i;
837 res->nh = nh;
838 res->fib6_flags = f6i->fib6_flags;
839 res->fib6_type = f6i->fib6_type;
840 }
841 }
842 }
843
844 static void find_rr_leaf(struct fib6_node *fn, struct fib6_info *leaf,
845 struct fib6_info *rr_head, int oif, int strict,
846 bool *do_rr, struct fib6_result *res)
847 {
848 u32 metric = rr_head->fib6_metric;
849 struct fib6_info *cont = NULL;
850 int mpri = -1;
851
852 __find_rr_leaf(rr_head, NULL, metric, res, &cont,
853 oif, strict, do_rr, &mpri);
854
855 __find_rr_leaf(leaf, rr_head, metric, res, &cont,
856 oif, strict, do_rr, &mpri);
857
858 if (res->f6i || !cont)
859 return;
860
861 __find_rr_leaf(cont, NULL, metric, res, NULL,
862 oif, strict, do_rr, &mpri);
863 }
864
865 static void rt6_select(struct net *net, struct fib6_node *fn, int oif,
866 struct fib6_result *res, int strict)
867 {
868 struct fib6_info *leaf = rcu_dereference(fn->leaf);
869 struct fib6_info *rt0;
870 bool do_rr = false;
871 int key_plen;
872
873 /* make sure this function or its helpers sets f6i */
874 res->f6i = NULL;
875
876 if (!leaf || leaf == net->ipv6.fib6_null_entry)
877 goto out;
878
879 rt0 = rcu_dereference(fn->rr_ptr);
880 if (!rt0)
881 rt0 = leaf;
882
883 /* Double check to make sure fn is not an intermediate node
884 * and fn->leaf does not points to its child's leaf
885 * (This might happen if all routes under fn are deleted from
886 * the tree and fib6_repair_tree() is called on the node.)
887 */
888 key_plen = rt0->fib6_dst.plen;
889 #ifdef CONFIG_IPV6_SUBTREES
890 if (rt0->fib6_src.plen)
891 key_plen = rt0->fib6_src.plen;
892 #endif
893 if (fn->fn_bit != key_plen)
894 goto out;
895
896 find_rr_leaf(fn, leaf, rt0, oif, strict, &do_rr, res);
897 if (do_rr) {
898 struct fib6_info *next = rcu_dereference(rt0->fib6_next);
899
900 /* no entries matched; do round-robin */
901 if (!next || next->fib6_metric != rt0->fib6_metric)
902 next = leaf;
903
904 if (next != rt0) {
905 spin_lock_bh(&leaf->fib6_table->tb6_lock);
906 /* make sure next is not being deleted from the tree */
907 if (next->fib6_node)
908 rcu_assign_pointer(fn->rr_ptr, next);
909 spin_unlock_bh(&leaf->fib6_table->tb6_lock);
910 }
911 }
912
913 out:
914 if (!res->f6i) {
915 res->f6i = net->ipv6.fib6_null_entry;
916 res->nh = res->f6i->fib6_nh;
917 res->fib6_flags = res->f6i->fib6_flags;
918 res->fib6_type = res->f6i->fib6_type;
919 }
920 }
921
922 static bool rt6_is_gw_or_nonexthop(const struct fib6_result *res)
923 {
924 return (res->f6i->fib6_flags & RTF_NONEXTHOP) ||
925 res->nh->fib_nh_gw_family;
926 }
927
928 #ifdef CONFIG_IPV6_ROUTE_INFO
929 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
930 const struct in6_addr *gwaddr)
931 {
932 struct net *net = dev_net(dev);
933 struct route_info *rinfo = (struct route_info *) opt;
934 struct in6_addr prefix_buf, *prefix;
935 unsigned int pref;
936 unsigned long lifetime;
937 struct fib6_info *rt;
938
939 if (len < sizeof(struct route_info)) {
940 return -EINVAL;
941 }
942
943 /* Sanity check for prefix_len and length */
944 if (rinfo->length > 3) {
945 return -EINVAL;
946 } else if (rinfo->prefix_len > 128) {
947 return -EINVAL;
948 } else if (rinfo->prefix_len > 64) {
949 if (rinfo->length < 2) {
950 return -EINVAL;
951 }
952 } else if (rinfo->prefix_len > 0) {
953 if (rinfo->length < 1) {
954 return -EINVAL;
955 }
956 }
957
958 pref = rinfo->route_pref;
959 if (pref == ICMPV6_ROUTER_PREF_INVALID)
960 return -EINVAL;
961
962 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
963
964 if (rinfo->length == 3)
965 prefix = (struct in6_addr *)rinfo->prefix;
966 else {
967 /* this function is safe */
968 ipv6_addr_prefix(&prefix_buf,
969 (struct in6_addr *)rinfo->prefix,
970 rinfo->prefix_len);
971 prefix = &prefix_buf;
972 }
973
974 if (rinfo->prefix_len == 0)
975 rt = rt6_get_dflt_router(net, gwaddr, dev);
976 else
977 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
978 gwaddr, dev);
979
980 if (rt && !lifetime) {
981 ip6_del_rt(net, rt);
982 rt = NULL;
983 }
984
985 if (!rt && lifetime)
986 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr,
987 dev, pref);
988 else if (rt)
989 rt->fib6_flags = RTF_ROUTEINFO |
990 (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
991
992 if (rt) {
993 if (!addrconf_finite_timeout(lifetime))
994 fib6_clean_expires(rt);
995 else
996 fib6_set_expires(rt, jiffies + HZ * lifetime);
997
998 fib6_info_release(rt);
999 }
1000 return 0;
1001 }
1002 #endif
1003
1004 /*
1005 * Misc support functions
1006 */
1007
1008 /* called with rcu_lock held */
1009 static struct net_device *ip6_rt_get_dev_rcu(const struct fib6_result *res)
1010 {
1011 struct net_device *dev = res->nh->fib_nh_dev;
1012
1013 if (res->fib6_flags & (RTF_LOCAL | RTF_ANYCAST)) {
1014 /* for copies of local routes, dst->dev needs to be the
1015 * device if it is a master device, the master device if
1016 * device is enslaved, and the loopback as the default
1017 */
1018 if (netif_is_l3_slave(dev) &&
1019 !rt6_need_strict(&res->f6i->fib6_dst.addr))
1020 dev = l3mdev_master_dev_rcu(dev);
1021 else if (!netif_is_l3_master(dev))
1022 dev = dev_net(dev)->loopback_dev;
1023 /* last case is netif_is_l3_master(dev) is true in which
1024 * case we want dev returned to be dev
1025 */
1026 }
1027
1028 return dev;
1029 }
1030
1031 static const int fib6_prop[RTN_MAX + 1] = {
1032 [RTN_UNSPEC] = 0,
1033 [RTN_UNICAST] = 0,
1034 [RTN_LOCAL] = 0,
1035 [RTN_BROADCAST] = 0,
1036 [RTN_ANYCAST] = 0,
1037 [RTN_MULTICAST] = 0,
1038 [RTN_BLACKHOLE] = -EINVAL,
1039 [RTN_UNREACHABLE] = -EHOSTUNREACH,
1040 [RTN_PROHIBIT] = -EACCES,
1041 [RTN_THROW] = -EAGAIN,
1042 [RTN_NAT] = -EINVAL,
1043 [RTN_XRESOLVE] = -EINVAL,
1044 };
1045
1046 static int ip6_rt_type_to_error(u8 fib6_type)
1047 {
1048 return fib6_prop[fib6_type];
1049 }
1050
1051 static unsigned short fib6_info_dst_flags(struct fib6_info *rt)
1052 {
1053 unsigned short flags = 0;
1054
1055 if (rt->dst_nocount)
1056 flags |= DST_NOCOUNT;
1057 if (rt->dst_nopolicy)
1058 flags |= DST_NOPOLICY;
1059 if (rt->dst_host)
1060 flags |= DST_HOST;
1061
1062 return flags;
1063 }
1064
1065 static void ip6_rt_init_dst_reject(struct rt6_info *rt, u8 fib6_type)
1066 {
1067 rt->dst.error = ip6_rt_type_to_error(fib6_type);
1068
1069 switch (fib6_type) {
1070 case RTN_BLACKHOLE:
1071 rt->dst.output = dst_discard_out;
1072 rt->dst.input = dst_discard;
1073 break;
1074 case RTN_PROHIBIT:
1075 rt->dst.output = ip6_pkt_prohibit_out;
1076 rt->dst.input = ip6_pkt_prohibit;
1077 break;
1078 case RTN_THROW:
1079 case RTN_UNREACHABLE:
1080 default:
1081 rt->dst.output = ip6_pkt_discard_out;
1082 rt->dst.input = ip6_pkt_discard;
1083 break;
1084 }
1085 }
1086
1087 static void ip6_rt_init_dst(struct rt6_info *rt, const struct fib6_result *res)
1088 {
1089 struct fib6_info *f6i = res->f6i;
1090
1091 if (res->fib6_flags & RTF_REJECT) {
1092 ip6_rt_init_dst_reject(rt, res->fib6_type);
1093 return;
1094 }
1095
1096 rt->dst.error = 0;
1097 rt->dst.output = ip6_output;
1098
1099 if (res->fib6_type == RTN_LOCAL || res->fib6_type == RTN_ANYCAST) {
1100 rt->dst.input = ip6_input;
1101 } else if (ipv6_addr_type(&f6i->fib6_dst.addr) & IPV6_ADDR_MULTICAST) {
1102 rt->dst.input = ip6_mc_input;
1103 } else {
1104 rt->dst.input = ip6_forward;
1105 }
1106
1107 if (res->nh->fib_nh_lws) {
1108 rt->dst.lwtstate = lwtstate_get(res->nh->fib_nh_lws);
1109 lwtunnel_set_redirect(&rt->dst);
1110 }
1111
1112 rt->dst.lastuse = jiffies;
1113 }
1114
1115 /* Caller must already hold reference to @from */
1116 static void rt6_set_from(struct rt6_info *rt, struct fib6_info *from)
1117 {
1118 rt->rt6i_flags &= ~RTF_EXPIRES;
1119 rcu_assign_pointer(rt->from, from);
1120 ip_dst_init_metrics(&rt->dst, from->fib6_metrics);
1121 }
1122
1123 /* Caller must already hold reference to f6i in result */
1124 static void ip6_rt_copy_init(struct rt6_info *rt, const struct fib6_result *res)
1125 {
1126 const struct fib6_nh *nh = res->nh;
1127 const struct net_device *dev = nh->fib_nh_dev;
1128 struct fib6_info *f6i = res->f6i;
1129
1130 ip6_rt_init_dst(rt, res);
1131
1132 rt->rt6i_dst = f6i->fib6_dst;
1133 rt->rt6i_idev = dev ? in6_dev_get(dev) : NULL;
1134 rt->rt6i_flags = res->fib6_flags;
1135 if (nh->fib_nh_gw_family) {
1136 rt->rt6i_gateway = nh->fib_nh_gw6;
1137 rt->rt6i_flags |= RTF_GATEWAY;
1138 }
1139 rt6_set_from(rt, f6i);
1140 #ifdef CONFIG_IPV6_SUBTREES
1141 rt->rt6i_src = f6i->fib6_src;
1142 #endif
1143 }
1144
1145 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
1146 struct in6_addr *saddr)
1147 {
1148 struct fib6_node *pn, *sn;
1149 while (1) {
1150 if (fn->fn_flags & RTN_TL_ROOT)
1151 return NULL;
1152 pn = rcu_dereference(fn->parent);
1153 sn = FIB6_SUBTREE(pn);
1154 if (sn && sn != fn)
1155 fn = fib6_node_lookup(sn, NULL, saddr);
1156 else
1157 fn = pn;
1158 if (fn->fn_flags & RTN_RTINFO)
1159 return fn;
1160 }
1161 }
1162
1163 static bool ip6_hold_safe(struct net *net, struct rt6_info **prt)
1164 {
1165 struct rt6_info *rt = *prt;
1166
1167 if (dst_hold_safe(&rt->dst))
1168 return true;
1169 if (net) {
1170 rt = net->ipv6.ip6_null_entry;
1171 dst_hold(&rt->dst);
1172 } else {
1173 rt = NULL;
1174 }
1175 *prt = rt;
1176 return false;
1177 }
1178
1179 /* called with rcu_lock held */
1180 static struct rt6_info *ip6_create_rt_rcu(const struct fib6_result *res)
1181 {
1182 struct net_device *dev = res->nh->fib_nh_dev;
1183 struct fib6_info *f6i = res->f6i;
1184 unsigned short flags;
1185 struct rt6_info *nrt;
1186
1187 if (!fib6_info_hold_safe(f6i))
1188 goto fallback;
1189
1190 flags = fib6_info_dst_flags(f6i);
1191 nrt = ip6_dst_alloc(dev_net(dev), dev, flags);
1192 if (!nrt) {
1193 fib6_info_release(f6i);
1194 goto fallback;
1195 }
1196
1197 ip6_rt_copy_init(nrt, res);
1198 return nrt;
1199
1200 fallback:
1201 nrt = dev_net(dev)->ipv6.ip6_null_entry;
1202 dst_hold(&nrt->dst);
1203 return nrt;
1204 }
1205
1206 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
1207 struct fib6_table *table,
1208 struct flowi6 *fl6,
1209 const struct sk_buff *skb,
1210 int flags)
1211 {
1212 struct fib6_result res = {};
1213 struct fib6_node *fn;
1214 struct rt6_info *rt;
1215
1216 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1217 flags &= ~RT6_LOOKUP_F_IFACE;
1218
1219 rcu_read_lock();
1220 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1221 restart:
1222 res.f6i = rcu_dereference(fn->leaf);
1223 if (!res.f6i)
1224 res.f6i = net->ipv6.fib6_null_entry;
1225 else
1226 rt6_device_match(net, &res, &fl6->saddr, fl6->flowi6_oif,
1227 flags);
1228
1229 if (res.f6i == net->ipv6.fib6_null_entry) {
1230 fn = fib6_backtrack(fn, &fl6->saddr);
1231 if (fn)
1232 goto restart;
1233
1234 rt = net->ipv6.ip6_null_entry;
1235 dst_hold(&rt->dst);
1236 goto out;
1237 } else if (res.fib6_flags & RTF_REJECT) {
1238 goto do_create;
1239 }
1240
1241 fib6_select_path(net, &res, fl6, fl6->flowi6_oif,
1242 fl6->flowi6_oif != 0, skb, flags);
1243
1244 /* Search through exception table */
1245 rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
1246 if (rt) {
1247 if (ip6_hold_safe(net, &rt))
1248 dst_use_noref(&rt->dst, jiffies);
1249 } else {
1250 do_create:
1251 rt = ip6_create_rt_rcu(&res);
1252 }
1253
1254 out:
1255 trace_fib6_table_lookup(net, &res, table, fl6);
1256
1257 rcu_read_unlock();
1258
1259 return rt;
1260 }
1261
1262 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
1263 const struct sk_buff *skb, int flags)
1264 {
1265 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_lookup);
1266 }
1267 EXPORT_SYMBOL_GPL(ip6_route_lookup);
1268
1269 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
1270 const struct in6_addr *saddr, int oif,
1271 const struct sk_buff *skb, int strict)
1272 {
1273 struct flowi6 fl6 = {
1274 .flowi6_oif = oif,
1275 .daddr = *daddr,
1276 };
1277 struct dst_entry *dst;
1278 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
1279
1280 if (saddr) {
1281 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
1282 flags |= RT6_LOOKUP_F_HAS_SADDR;
1283 }
1284
1285 dst = fib6_rule_lookup(net, &fl6, skb, flags, ip6_pol_route_lookup);
1286 if (dst->error == 0)
1287 return (struct rt6_info *) dst;
1288
1289 dst_release(dst);
1290
1291 return NULL;
1292 }
1293 EXPORT_SYMBOL(rt6_lookup);
1294
1295 /* ip6_ins_rt is called with FREE table->tb6_lock.
1296 * It takes new route entry, the addition fails by any reason the
1297 * route is released.
1298 * Caller must hold dst before calling it.
1299 */
1300
1301 static int __ip6_ins_rt(struct fib6_info *rt, struct nl_info *info,
1302 struct netlink_ext_ack *extack)
1303 {
1304 int err;
1305 struct fib6_table *table;
1306
1307 table = rt->fib6_table;
1308 spin_lock_bh(&table->tb6_lock);
1309 err = fib6_add(&table->tb6_root, rt, info, extack);
1310 spin_unlock_bh(&table->tb6_lock);
1311
1312 return err;
1313 }
1314
1315 int ip6_ins_rt(struct net *net, struct fib6_info *rt)
1316 {
1317 struct nl_info info = { .nl_net = net, };
1318
1319 return __ip6_ins_rt(rt, &info, NULL);
1320 }
1321
1322 static struct rt6_info *ip6_rt_cache_alloc(const struct fib6_result *res,
1323 const struct in6_addr *daddr,
1324 const struct in6_addr *saddr)
1325 {
1326 struct fib6_info *f6i = res->f6i;
1327 struct net_device *dev;
1328 struct rt6_info *rt;
1329
1330 /*
1331 * Clone the route.
1332 */
1333
1334 if (!fib6_info_hold_safe(f6i))
1335 return NULL;
1336
1337 dev = ip6_rt_get_dev_rcu(res);
1338 rt = ip6_dst_alloc(dev_net(dev), dev, 0);
1339 if (!rt) {
1340 fib6_info_release(f6i);
1341 return NULL;
1342 }
1343
1344 ip6_rt_copy_init(rt, res);
1345 rt->rt6i_flags |= RTF_CACHE;
1346 rt->dst.flags |= DST_HOST;
1347 rt->rt6i_dst.addr = *daddr;
1348 rt->rt6i_dst.plen = 128;
1349
1350 if (!rt6_is_gw_or_nonexthop(res)) {
1351 if (f6i->fib6_dst.plen != 128 &&
1352 ipv6_addr_equal(&f6i->fib6_dst.addr, daddr))
1353 rt->rt6i_flags |= RTF_ANYCAST;
1354 #ifdef CONFIG_IPV6_SUBTREES
1355 if (rt->rt6i_src.plen && saddr) {
1356 rt->rt6i_src.addr = *saddr;
1357 rt->rt6i_src.plen = 128;
1358 }
1359 #endif
1360 }
1361
1362 return rt;
1363 }
1364
1365 static struct rt6_info *ip6_rt_pcpu_alloc(const struct fib6_result *res)
1366 {
1367 struct fib6_info *f6i = res->f6i;
1368 unsigned short flags = fib6_info_dst_flags(f6i);
1369 struct net_device *dev;
1370 struct rt6_info *pcpu_rt;
1371
1372 if (!fib6_info_hold_safe(f6i))
1373 return NULL;
1374
1375 rcu_read_lock();
1376 dev = ip6_rt_get_dev_rcu(res);
1377 pcpu_rt = ip6_dst_alloc(dev_net(dev), dev, flags);
1378 rcu_read_unlock();
1379 if (!pcpu_rt) {
1380 fib6_info_release(f6i);
1381 return NULL;
1382 }
1383 ip6_rt_copy_init(pcpu_rt, res);
1384 pcpu_rt->rt6i_flags |= RTF_PCPU;
1385 return pcpu_rt;
1386 }
1387
1388 /* It should be called with rcu_read_lock() acquired */
1389 static struct rt6_info *rt6_get_pcpu_route(const struct fib6_result *res)
1390 {
1391 struct rt6_info *pcpu_rt;
1392
1393 pcpu_rt = this_cpu_read(*res->nh->rt6i_pcpu);
1394
1395 return pcpu_rt;
1396 }
1397
1398 static struct rt6_info *rt6_make_pcpu_route(struct net *net,
1399 const struct fib6_result *res)
1400 {
1401 struct rt6_info *pcpu_rt, *prev, **p;
1402
1403 pcpu_rt = ip6_rt_pcpu_alloc(res);
1404 if (!pcpu_rt)
1405 return NULL;
1406
1407 p = this_cpu_ptr(res->nh->rt6i_pcpu);
1408 prev = cmpxchg(p, NULL, pcpu_rt);
1409 BUG_ON(prev);
1410
1411 if (res->f6i->fib6_destroying) {
1412 struct fib6_info *from;
1413
1414 from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL);
1415 fib6_info_release(from);
1416 }
1417
1418 return pcpu_rt;
1419 }
1420
1421 /* exception hash table implementation
1422 */
1423 static DEFINE_SPINLOCK(rt6_exception_lock);
1424
1425 /* Remove rt6_ex from hash table and free the memory
1426 * Caller must hold rt6_exception_lock
1427 */
1428 static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
1429 struct rt6_exception *rt6_ex)
1430 {
1431 struct fib6_info *from;
1432 struct net *net;
1433
1434 if (!bucket || !rt6_ex)
1435 return;
1436
1437 net = dev_net(rt6_ex->rt6i->dst.dev);
1438 net->ipv6.rt6_stats->fib_rt_cache--;
1439
1440 /* purge completely the exception to allow releasing the held resources:
1441 * some [sk] cache may keep the dst around for unlimited time
1442 */
1443 from = xchg((__force struct fib6_info **)&rt6_ex->rt6i->from, NULL);
1444 fib6_info_release(from);
1445 dst_dev_put(&rt6_ex->rt6i->dst);
1446
1447 hlist_del_rcu(&rt6_ex->hlist);
1448 dst_release(&rt6_ex->rt6i->dst);
1449 kfree_rcu(rt6_ex, rcu);
1450 WARN_ON_ONCE(!bucket->depth);
1451 bucket->depth--;
1452 }
1453
1454 /* Remove oldest rt6_ex in bucket and free the memory
1455 * Caller must hold rt6_exception_lock
1456 */
1457 static void rt6_exception_remove_oldest(struct rt6_exception_bucket *bucket)
1458 {
1459 struct rt6_exception *rt6_ex, *oldest = NULL;
1460
1461 if (!bucket)
1462 return;
1463
1464 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
1465 if (!oldest || time_before(rt6_ex->stamp, oldest->stamp))
1466 oldest = rt6_ex;
1467 }
1468 rt6_remove_exception(bucket, oldest);
1469 }
1470
1471 static u32 rt6_exception_hash(const struct in6_addr *dst,
1472 const struct in6_addr *src)
1473 {
1474 static u32 seed __read_mostly;
1475 u32 val;
1476
1477 net_get_random_once(&seed, sizeof(seed));
1478 val = jhash(dst, sizeof(*dst), seed);
1479
1480 #ifdef CONFIG_IPV6_SUBTREES
1481 if (src)
1482 val = jhash(src, sizeof(*src), val);
1483 #endif
1484 return hash_32(val, FIB6_EXCEPTION_BUCKET_SIZE_SHIFT);
1485 }
1486
1487 /* Helper function to find the cached rt in the hash table
1488 * and update bucket pointer to point to the bucket for this
1489 * (daddr, saddr) pair
1490 * Caller must hold rt6_exception_lock
1491 */
1492 static struct rt6_exception *
1493 __rt6_find_exception_spinlock(struct rt6_exception_bucket **bucket,
1494 const struct in6_addr *daddr,
1495 const struct in6_addr *saddr)
1496 {
1497 struct rt6_exception *rt6_ex;
1498 u32 hval;
1499
1500 if (!(*bucket) || !daddr)
1501 return NULL;
1502
1503 hval = rt6_exception_hash(daddr, saddr);
1504 *bucket += hval;
1505
1506 hlist_for_each_entry(rt6_ex, &(*bucket)->chain, hlist) {
1507 struct rt6_info *rt6 = rt6_ex->rt6i;
1508 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1509
1510 #ifdef CONFIG_IPV6_SUBTREES
1511 if (matched && saddr)
1512 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1513 #endif
1514 if (matched)
1515 return rt6_ex;
1516 }
1517 return NULL;
1518 }
1519
1520 /* Helper function to find the cached rt in the hash table
1521 * and update bucket pointer to point to the bucket for this
1522 * (daddr, saddr) pair
1523 * Caller must hold rcu_read_lock()
1524 */
1525 static struct rt6_exception *
1526 __rt6_find_exception_rcu(struct rt6_exception_bucket **bucket,
1527 const struct in6_addr *daddr,
1528 const struct in6_addr *saddr)
1529 {
1530 struct rt6_exception *rt6_ex;
1531 u32 hval;
1532
1533 WARN_ON_ONCE(!rcu_read_lock_held());
1534
1535 if (!(*bucket) || !daddr)
1536 return NULL;
1537
1538 hval = rt6_exception_hash(daddr, saddr);
1539 *bucket += hval;
1540
1541 hlist_for_each_entry_rcu(rt6_ex, &(*bucket)->chain, hlist) {
1542 struct rt6_info *rt6 = rt6_ex->rt6i;
1543 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1544
1545 #ifdef CONFIG_IPV6_SUBTREES
1546 if (matched && saddr)
1547 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1548 #endif
1549 if (matched)
1550 return rt6_ex;
1551 }
1552 return NULL;
1553 }
1554
1555 static unsigned int fib6_mtu(const struct fib6_result *res)
1556 {
1557 const struct fib6_nh *nh = res->nh;
1558 unsigned int mtu;
1559
1560 if (res->f6i->fib6_pmtu) {
1561 mtu = res->f6i->fib6_pmtu;
1562 } else {
1563 struct net_device *dev = nh->fib_nh_dev;
1564 struct inet6_dev *idev;
1565
1566 rcu_read_lock();
1567 idev = __in6_dev_get(dev);
1568 mtu = idev->cnf.mtu6;
1569 rcu_read_unlock();
1570 }
1571
1572 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
1573
1574 return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
1575 }
1576
1577 #define FIB6_EXCEPTION_BUCKET_FLUSHED 0x1UL
1578
1579 /* used when the flushed bit is not relevant, only access to the bucket
1580 * (ie., all bucket users except rt6_insert_exception);
1581 *
1582 * called under rcu lock; sometimes called with rt6_exception_lock held
1583 */
1584 static
1585 struct rt6_exception_bucket *fib6_nh_get_excptn_bucket(const struct fib6_nh *nh,
1586 spinlock_t *lock)
1587 {
1588 struct rt6_exception_bucket *bucket;
1589
1590 if (lock)
1591 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1592 lockdep_is_held(lock));
1593 else
1594 bucket = rcu_dereference(nh->rt6i_exception_bucket);
1595
1596 /* remove bucket flushed bit if set */
1597 if (bucket) {
1598 unsigned long p = (unsigned long)bucket;
1599
1600 p &= ~FIB6_EXCEPTION_BUCKET_FLUSHED;
1601 bucket = (struct rt6_exception_bucket *)p;
1602 }
1603
1604 return bucket;
1605 }
1606
1607 static bool fib6_nh_excptn_bucket_flushed(struct rt6_exception_bucket *bucket)
1608 {
1609 unsigned long p = (unsigned long)bucket;
1610
1611 return !!(p & FIB6_EXCEPTION_BUCKET_FLUSHED);
1612 }
1613
1614 /* called with rt6_exception_lock held */
1615 static void fib6_nh_excptn_bucket_set_flushed(struct fib6_nh *nh,
1616 spinlock_t *lock)
1617 {
1618 struct rt6_exception_bucket *bucket;
1619 unsigned long p;
1620
1621 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1622 lockdep_is_held(lock));
1623
1624 p = (unsigned long)bucket;
1625 p |= FIB6_EXCEPTION_BUCKET_FLUSHED;
1626 bucket = (struct rt6_exception_bucket *)p;
1627 rcu_assign_pointer(nh->rt6i_exception_bucket, bucket);
1628 }
1629
1630 static int rt6_insert_exception(struct rt6_info *nrt,
1631 const struct fib6_result *res)
1632 {
1633 struct net *net = dev_net(nrt->dst.dev);
1634 struct rt6_exception_bucket *bucket;
1635 struct fib6_info *f6i = res->f6i;
1636 struct in6_addr *src_key = NULL;
1637 struct rt6_exception *rt6_ex;
1638 struct fib6_nh *nh = res->nh;
1639 int err = 0;
1640
1641 spin_lock_bh(&rt6_exception_lock);
1642
1643 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1644 lockdep_is_held(&rt6_exception_lock));
1645 if (!bucket) {
1646 bucket = kcalloc(FIB6_EXCEPTION_BUCKET_SIZE, sizeof(*bucket),
1647 GFP_ATOMIC);
1648 if (!bucket) {
1649 err = -ENOMEM;
1650 goto out;
1651 }
1652 rcu_assign_pointer(nh->rt6i_exception_bucket, bucket);
1653 } else if (fib6_nh_excptn_bucket_flushed(bucket)) {
1654 err = -EINVAL;
1655 goto out;
1656 }
1657
1658 #ifdef CONFIG_IPV6_SUBTREES
1659 /* fib6_src.plen != 0 indicates f6i is in subtree
1660 * and exception table is indexed by a hash of
1661 * both fib6_dst and fib6_src.
1662 * Otherwise, the exception table is indexed by
1663 * a hash of only fib6_dst.
1664 */
1665 if (f6i->fib6_src.plen)
1666 src_key = &nrt->rt6i_src.addr;
1667 #endif
1668 /* rt6_mtu_change() might lower mtu on f6i.
1669 * Only insert this exception route if its mtu
1670 * is less than f6i's mtu value.
1671 */
1672 if (dst_metric_raw(&nrt->dst, RTAX_MTU) >= fib6_mtu(res)) {
1673 err = -EINVAL;
1674 goto out;
1675 }
1676
1677 rt6_ex = __rt6_find_exception_spinlock(&bucket, &nrt->rt6i_dst.addr,
1678 src_key);
1679 if (rt6_ex)
1680 rt6_remove_exception(bucket, rt6_ex);
1681
1682 rt6_ex = kzalloc(sizeof(*rt6_ex), GFP_ATOMIC);
1683 if (!rt6_ex) {
1684 err = -ENOMEM;
1685 goto out;
1686 }
1687 rt6_ex->rt6i = nrt;
1688 rt6_ex->stamp = jiffies;
1689 hlist_add_head_rcu(&rt6_ex->hlist, &bucket->chain);
1690 bucket->depth++;
1691 net->ipv6.rt6_stats->fib_rt_cache++;
1692
1693 if (bucket->depth > FIB6_MAX_DEPTH)
1694 rt6_exception_remove_oldest(bucket);
1695
1696 out:
1697 spin_unlock_bh(&rt6_exception_lock);
1698
1699 /* Update fn->fn_sernum to invalidate all cached dst */
1700 if (!err) {
1701 spin_lock_bh(&f6i->fib6_table->tb6_lock);
1702 fib6_update_sernum(net, f6i);
1703 spin_unlock_bh(&f6i->fib6_table->tb6_lock);
1704 fib6_force_start_gc(net);
1705 }
1706
1707 return err;
1708 }
1709
1710 static void fib6_nh_flush_exceptions(struct fib6_nh *nh, struct fib6_info *from)
1711 {
1712 struct rt6_exception_bucket *bucket;
1713 struct rt6_exception *rt6_ex;
1714 struct hlist_node *tmp;
1715 int i;
1716
1717 spin_lock_bh(&rt6_exception_lock);
1718
1719 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1720 if (!bucket)
1721 goto out;
1722
1723 /* Prevent rt6_insert_exception() to recreate the bucket list */
1724 if (!from)
1725 fib6_nh_excptn_bucket_set_flushed(nh, &rt6_exception_lock);
1726
1727 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1728 hlist_for_each_entry_safe(rt6_ex, tmp, &bucket->chain, hlist) {
1729 if (!from ||
1730 rcu_access_pointer(rt6_ex->rt6i->from) == from)
1731 rt6_remove_exception(bucket, rt6_ex);
1732 }
1733 WARN_ON_ONCE(!from && bucket->depth);
1734 bucket++;
1735 }
1736 out:
1737 spin_unlock_bh(&rt6_exception_lock);
1738 }
1739
1740 static int rt6_nh_flush_exceptions(struct fib6_nh *nh, void *arg)
1741 {
1742 struct fib6_info *f6i = arg;
1743
1744 fib6_nh_flush_exceptions(nh, f6i);
1745
1746 return 0;
1747 }
1748
1749 void rt6_flush_exceptions(struct fib6_info *f6i)
1750 {
1751 if (f6i->nh)
1752 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_flush_exceptions,
1753 f6i);
1754 else
1755 fib6_nh_flush_exceptions(f6i->fib6_nh, f6i);
1756 }
1757
1758 /* Find cached rt in the hash table inside passed in rt
1759 * Caller has to hold rcu_read_lock()
1760 */
1761 static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res,
1762 const struct in6_addr *daddr,
1763 const struct in6_addr *saddr)
1764 {
1765 const struct in6_addr *src_key = NULL;
1766 struct rt6_exception_bucket *bucket;
1767 struct rt6_exception *rt6_ex;
1768 struct rt6_info *ret = NULL;
1769
1770 #ifdef CONFIG_IPV6_SUBTREES
1771 /* fib6i_src.plen != 0 indicates f6i is in subtree
1772 * and exception table is indexed by a hash of
1773 * both fib6_dst and fib6_src.
1774 * However, the src addr used to create the hash
1775 * might not be exactly the passed in saddr which
1776 * is a /128 addr from the flow.
1777 * So we need to use f6i->fib6_src to redo lookup
1778 * if the passed in saddr does not find anything.
1779 * (See the logic in ip6_rt_cache_alloc() on how
1780 * rt->rt6i_src is updated.)
1781 */
1782 if (res->f6i->fib6_src.plen)
1783 src_key = saddr;
1784 find_ex:
1785 #endif
1786 bucket = fib6_nh_get_excptn_bucket(res->nh, NULL);
1787 rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key);
1788
1789 if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i))
1790 ret = rt6_ex->rt6i;
1791
1792 #ifdef CONFIG_IPV6_SUBTREES
1793 /* Use fib6_src as src_key and redo lookup */
1794 if (!ret && src_key && src_key != &res->f6i->fib6_src.addr) {
1795 src_key = &res->f6i->fib6_src.addr;
1796 goto find_ex;
1797 }
1798 #endif
1799
1800 return ret;
1801 }
1802
1803 /* Remove the passed in cached rt from the hash table that contains it */
1804 static int fib6_nh_remove_exception(const struct fib6_nh *nh, int plen,
1805 const struct rt6_info *rt)
1806 {
1807 const struct in6_addr *src_key = NULL;
1808 struct rt6_exception_bucket *bucket;
1809 struct rt6_exception *rt6_ex;
1810 int err;
1811
1812 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
1813 return -ENOENT;
1814
1815 spin_lock_bh(&rt6_exception_lock);
1816 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1817
1818 #ifdef CONFIG_IPV6_SUBTREES
1819 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1820 * and exception table is indexed by a hash of
1821 * both rt6i_dst and rt6i_src.
1822 * Otherwise, the exception table is indexed by
1823 * a hash of only rt6i_dst.
1824 */
1825 if (plen)
1826 src_key = &rt->rt6i_src.addr;
1827 #endif
1828 rt6_ex = __rt6_find_exception_spinlock(&bucket,
1829 &rt->rt6i_dst.addr,
1830 src_key);
1831 if (rt6_ex) {
1832 rt6_remove_exception(bucket, rt6_ex);
1833 err = 0;
1834 } else {
1835 err = -ENOENT;
1836 }
1837
1838 spin_unlock_bh(&rt6_exception_lock);
1839 return err;
1840 }
1841
1842 struct fib6_nh_excptn_arg {
1843 struct rt6_info *rt;
1844 int plen;
1845 };
1846
1847 static int rt6_nh_remove_exception_rt(struct fib6_nh *nh, void *_arg)
1848 {
1849 struct fib6_nh_excptn_arg *arg = _arg;
1850 int err;
1851
1852 err = fib6_nh_remove_exception(nh, arg->plen, arg->rt);
1853 if (err == 0)
1854 return 1;
1855
1856 return 0;
1857 }
1858
1859 static int rt6_remove_exception_rt(struct rt6_info *rt)
1860 {
1861 struct fib6_info *from;
1862
1863 from = rcu_dereference(rt->from);
1864 if (!from || !(rt->rt6i_flags & RTF_CACHE))
1865 return -EINVAL;
1866
1867 if (from->nh) {
1868 struct fib6_nh_excptn_arg arg = {
1869 .rt = rt,
1870 .plen = from->fib6_src.plen
1871 };
1872 int rc;
1873
1874 /* rc = 1 means an entry was found */
1875 rc = nexthop_for_each_fib6_nh(from->nh,
1876 rt6_nh_remove_exception_rt,
1877 &arg);
1878 return rc ? 0 : -ENOENT;
1879 }
1880
1881 return fib6_nh_remove_exception(from->fib6_nh,
1882 from->fib6_src.plen, rt);
1883 }
1884
1885 /* Find rt6_ex which contains the passed in rt cache and
1886 * refresh its stamp
1887 */
1888 static void fib6_nh_update_exception(const struct fib6_nh *nh, int plen,
1889 const struct rt6_info *rt)
1890 {
1891 const struct in6_addr *src_key = NULL;
1892 struct rt6_exception_bucket *bucket;
1893 struct rt6_exception *rt6_ex;
1894
1895 bucket = fib6_nh_get_excptn_bucket(nh, NULL);
1896 #ifdef CONFIG_IPV6_SUBTREES
1897 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1898 * and exception table is indexed by a hash of
1899 * both rt6i_dst and rt6i_src.
1900 * Otherwise, the exception table is indexed by
1901 * a hash of only rt6i_dst.
1902 */
1903 if (plen)
1904 src_key = &rt->rt6i_src.addr;
1905 #endif
1906 rt6_ex = __rt6_find_exception_rcu(&bucket, &rt->rt6i_dst.addr, src_key);
1907 if (rt6_ex)
1908 rt6_ex->stamp = jiffies;
1909 }
1910
1911 struct fib6_nh_match_arg {
1912 const struct net_device *dev;
1913 const struct in6_addr *gw;
1914 struct fib6_nh *match;
1915 };
1916
1917 /* determine if fib6_nh has given device and gateway */
1918 static int fib6_nh_find_match(struct fib6_nh *nh, void *_arg)
1919 {
1920 struct fib6_nh_match_arg *arg = _arg;
1921
1922 if (arg->dev != nh->fib_nh_dev ||
1923 (arg->gw && !nh->fib_nh_gw_family) ||
1924 (!arg->gw && nh->fib_nh_gw_family) ||
1925 (arg->gw && !ipv6_addr_equal(arg->gw, &nh->fib_nh_gw6)))
1926 return 0;
1927
1928 arg->match = nh;
1929
1930 /* found a match, break the loop */
1931 return 1;
1932 }
1933
1934 static void rt6_update_exception_stamp_rt(struct rt6_info *rt)
1935 {
1936 struct fib6_info *from;
1937 struct fib6_nh *fib6_nh;
1938
1939 rcu_read_lock();
1940
1941 from = rcu_dereference(rt->from);
1942 if (!from || !(rt->rt6i_flags & RTF_CACHE))
1943 goto unlock;
1944
1945 if (from->nh) {
1946 struct fib6_nh_match_arg arg = {
1947 .dev = rt->dst.dev,
1948 .gw = &rt->rt6i_gateway,
1949 };
1950
1951 nexthop_for_each_fib6_nh(from->nh, fib6_nh_find_match, &arg);
1952
1953 if (!arg.match)
1954 goto unlock;
1955 fib6_nh = arg.match;
1956 } else {
1957 fib6_nh = from->fib6_nh;
1958 }
1959 fib6_nh_update_exception(fib6_nh, from->fib6_src.plen, rt);
1960 unlock:
1961 rcu_read_unlock();
1962 }
1963
1964 static bool rt6_mtu_change_route_allowed(struct inet6_dev *idev,
1965 struct rt6_info *rt, int mtu)
1966 {
1967 /* If the new MTU is lower than the route PMTU, this new MTU will be the
1968 * lowest MTU in the path: always allow updating the route PMTU to
1969 * reflect PMTU decreases.
1970 *
1971 * If the new MTU is higher, and the route PMTU is equal to the local
1972 * MTU, this means the old MTU is the lowest in the path, so allow
1973 * updating it: if other nodes now have lower MTUs, PMTU discovery will
1974 * handle this.
1975 */
1976
1977 if (dst_mtu(&rt->dst) >= mtu)
1978 return true;
1979
1980 if (dst_mtu(&rt->dst) == idev->cnf.mtu6)
1981 return true;
1982
1983 return false;
1984 }
1985
1986 static void rt6_exceptions_update_pmtu(struct inet6_dev *idev,
1987 const struct fib6_nh *nh, int mtu)
1988 {
1989 struct rt6_exception_bucket *bucket;
1990 struct rt6_exception *rt6_ex;
1991 int i;
1992
1993 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1994 if (!bucket)
1995 return;
1996
1997 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1998 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
1999 struct rt6_info *entry = rt6_ex->rt6i;
2000
2001 /* For RTF_CACHE with rt6i_pmtu == 0 (i.e. a redirected
2002 * route), the metrics of its rt->from have already
2003 * been updated.
2004 */
2005 if (dst_metric_raw(&entry->dst, RTAX_MTU) &&
2006 rt6_mtu_change_route_allowed(idev, entry, mtu))
2007 dst_metric_set(&entry->dst, RTAX_MTU, mtu);
2008 }
2009 bucket++;
2010 }
2011 }
2012
2013 #define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
2014
2015 static void fib6_nh_exceptions_clean_tohost(const struct fib6_nh *nh,
2016 const struct in6_addr *gateway)
2017 {
2018 struct rt6_exception_bucket *bucket;
2019 struct rt6_exception *rt6_ex;
2020 struct hlist_node *tmp;
2021 int i;
2022
2023 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
2024 return;
2025
2026 spin_lock_bh(&rt6_exception_lock);
2027 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2028 if (bucket) {
2029 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2030 hlist_for_each_entry_safe(rt6_ex, tmp,
2031 &bucket->chain, hlist) {
2032 struct rt6_info *entry = rt6_ex->rt6i;
2033
2034 if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) ==
2035 RTF_CACHE_GATEWAY &&
2036 ipv6_addr_equal(gateway,
2037 &entry->rt6i_gateway)) {
2038 rt6_remove_exception(bucket, rt6_ex);
2039 }
2040 }
2041 bucket++;
2042 }
2043 }
2044
2045 spin_unlock_bh(&rt6_exception_lock);
2046 }
2047
2048 static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
2049 struct rt6_exception *rt6_ex,
2050 struct fib6_gc_args *gc_args,
2051 unsigned long now)
2052 {
2053 struct rt6_info *rt = rt6_ex->rt6i;
2054
2055 /* we are pruning and obsoleting aged-out and non gateway exceptions
2056 * even if others have still references to them, so that on next
2057 * dst_check() such references can be dropped.
2058 * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when
2059 * expired, independently from their aging, as per RFC 8201 section 4
2060 */
2061 if (!(rt->rt6i_flags & RTF_EXPIRES)) {
2062 if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
2063 RT6_TRACE("aging clone %p\n", rt);
2064 rt6_remove_exception(bucket, rt6_ex);
2065 return;
2066 }
2067 } else if (time_after(jiffies, rt->dst.expires)) {
2068 RT6_TRACE("purging expired route %p\n", rt);
2069 rt6_remove_exception(bucket, rt6_ex);
2070 return;
2071 }
2072
2073 if (rt->rt6i_flags & RTF_GATEWAY) {
2074 struct neighbour *neigh;
2075 __u8 neigh_flags = 0;
2076
2077 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
2078 if (neigh)
2079 neigh_flags = neigh->flags;
2080
2081 if (!(neigh_flags & NTF_ROUTER)) {
2082 RT6_TRACE("purging route %p via non-router but gateway\n",
2083 rt);
2084 rt6_remove_exception(bucket, rt6_ex);
2085 return;
2086 }
2087 }
2088
2089 gc_args->more++;
2090 }
2091
2092 static void fib6_nh_age_exceptions(const struct fib6_nh *nh,
2093 struct fib6_gc_args *gc_args,
2094 unsigned long now)
2095 {
2096 struct rt6_exception_bucket *bucket;
2097 struct rt6_exception *rt6_ex;
2098 struct hlist_node *tmp;
2099 int i;
2100
2101 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
2102 return;
2103
2104 rcu_read_lock_bh();
2105 spin_lock(&rt6_exception_lock);
2106 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2107 if (bucket) {
2108 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2109 hlist_for_each_entry_safe(rt6_ex, tmp,
2110 &bucket->chain, hlist) {
2111 rt6_age_examine_exception(bucket, rt6_ex,
2112 gc_args, now);
2113 }
2114 bucket++;
2115 }
2116 }
2117 spin_unlock(&rt6_exception_lock);
2118 rcu_read_unlock_bh();
2119 }
2120
2121 struct fib6_nh_age_excptn_arg {
2122 struct fib6_gc_args *gc_args;
2123 unsigned long now;
2124 };
2125
2126 static int rt6_nh_age_exceptions(struct fib6_nh *nh, void *_arg)
2127 {
2128 struct fib6_nh_age_excptn_arg *arg = _arg;
2129
2130 fib6_nh_age_exceptions(nh, arg->gc_args, arg->now);
2131 return 0;
2132 }
2133
2134 void rt6_age_exceptions(struct fib6_info *f6i,
2135 struct fib6_gc_args *gc_args,
2136 unsigned long now)
2137 {
2138 if (f6i->nh) {
2139 struct fib6_nh_age_excptn_arg arg = {
2140 .gc_args = gc_args,
2141 .now = now
2142 };
2143
2144 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_age_exceptions,
2145 &arg);
2146 } else {
2147 fib6_nh_age_exceptions(f6i->fib6_nh, gc_args, now);
2148 }
2149 }
2150
2151 /* must be called with rcu lock held */
2152 int fib6_table_lookup(struct net *net, struct fib6_table *table, int oif,
2153 struct flowi6 *fl6, struct fib6_result *res, int strict)
2154 {
2155 struct fib6_node *fn, *saved_fn;
2156
2157 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
2158 saved_fn = fn;
2159
2160 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
2161 oif = 0;
2162
2163 redo_rt6_select:
2164 rt6_select(net, fn, oif, res, strict);
2165 if (res->f6i == net->ipv6.fib6_null_entry) {
2166 fn = fib6_backtrack(fn, &fl6->saddr);
2167 if (fn)
2168 goto redo_rt6_select;
2169 else if (strict & RT6_LOOKUP_F_REACHABLE) {
2170 /* also consider unreachable route */
2171 strict &= ~RT6_LOOKUP_F_REACHABLE;
2172 fn = saved_fn;
2173 goto redo_rt6_select;
2174 }
2175 }
2176
2177 trace_fib6_table_lookup(net, res, table, fl6);
2178
2179 return 0;
2180 }
2181
2182 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
2183 int oif, struct flowi6 *fl6,
2184 const struct sk_buff *skb, int flags)
2185 {
2186 struct fib6_result res = {};
2187 struct rt6_info *rt = NULL;
2188 int strict = 0;
2189
2190 WARN_ON_ONCE((flags & RT6_LOOKUP_F_DST_NOREF) &&
2191 !rcu_read_lock_held());
2192
2193 strict |= flags & RT6_LOOKUP_F_IFACE;
2194 strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE;
2195 if (net->ipv6.devconf_all->forwarding == 0)
2196 strict |= RT6_LOOKUP_F_REACHABLE;
2197
2198 rcu_read_lock();
2199
2200 fib6_table_lookup(net, table, oif, fl6, &res, strict);
2201 if (res.f6i == net->ipv6.fib6_null_entry)
2202 goto out;
2203
2204 fib6_select_path(net, &res, fl6, oif, false, skb, strict);
2205
2206 /*Search through exception table */
2207 rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
2208 if (rt) {
2209 goto out;
2210 } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
2211 !res.nh->fib_nh_gw_family)) {
2212 /* Create a RTF_CACHE clone which will not be
2213 * owned by the fib6 tree. It is for the special case where
2214 * the daddr in the skb during the neighbor look-up is different
2215 * from the fl6->daddr used to look-up route here.
2216 */
2217 rt = ip6_rt_cache_alloc(&res, &fl6->daddr, NULL);
2218
2219 if (rt) {
2220 /* 1 refcnt is taken during ip6_rt_cache_alloc().
2221 * As rt6_uncached_list_add() does not consume refcnt,
2222 * this refcnt is always returned to the caller even
2223 * if caller sets RT6_LOOKUP_F_DST_NOREF flag.
2224 */
2225 rt6_uncached_list_add(rt);
2226 atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
2227 rcu_read_unlock();
2228
2229 return rt;
2230 }
2231 } else {
2232 /* Get a percpu copy */
2233 local_bh_disable();
2234 rt = rt6_get_pcpu_route(&res);
2235
2236 if (!rt)
2237 rt = rt6_make_pcpu_route(net, &res);
2238
2239 local_bh_enable();
2240 }
2241 out:
2242 if (!rt)
2243 rt = net->ipv6.ip6_null_entry;
2244 if (!(flags & RT6_LOOKUP_F_DST_NOREF))
2245 ip6_hold_safe(net, &rt);
2246 rcu_read_unlock();
2247
2248 return rt;
2249 }
2250 EXPORT_SYMBOL_GPL(ip6_pol_route);
2251
2252 static struct rt6_info *ip6_pol_route_input(struct net *net,
2253 struct fib6_table *table,
2254 struct flowi6 *fl6,
2255 const struct sk_buff *skb,
2256 int flags)
2257 {
2258 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, skb, flags);
2259 }
2260
2261 struct dst_entry *ip6_route_input_lookup(struct net *net,
2262 struct net_device *dev,
2263 struct flowi6 *fl6,
2264 const struct sk_buff *skb,
2265 int flags)
2266 {
2267 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
2268 flags |= RT6_LOOKUP_F_IFACE;
2269
2270 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_input);
2271 }
2272 EXPORT_SYMBOL_GPL(ip6_route_input_lookup);
2273
2274 static void ip6_multipath_l3_keys(const struct sk_buff *skb,
2275 struct flow_keys *keys,
2276 struct flow_keys *flkeys)
2277 {
2278 const struct ipv6hdr *outer_iph = ipv6_hdr(skb);
2279 const struct ipv6hdr *key_iph = outer_iph;
2280 struct flow_keys *_flkeys = flkeys;
2281 const struct ipv6hdr *inner_iph;
2282 const struct icmp6hdr *icmph;
2283 struct ipv6hdr _inner_iph;
2284 struct icmp6hdr _icmph;
2285
2286 if (likely(outer_iph->nexthdr != IPPROTO_ICMPV6))
2287 goto out;
2288
2289 icmph = skb_header_pointer(skb, skb_transport_offset(skb),
2290 sizeof(_icmph), &_icmph);
2291 if (!icmph)
2292 goto out;
2293
2294 if (icmph->icmp6_type != ICMPV6_DEST_UNREACH &&
2295 icmph->icmp6_type != ICMPV6_PKT_TOOBIG &&
2296 icmph->icmp6_type != ICMPV6_TIME_EXCEED &&
2297 icmph->icmp6_type != ICMPV6_PARAMPROB)
2298 goto out;
2299
2300 inner_iph = skb_header_pointer(skb,
2301 skb_transport_offset(skb) + sizeof(*icmph),
2302 sizeof(_inner_iph), &_inner_iph);
2303 if (!inner_iph)
2304 goto out;
2305
2306 key_iph = inner_iph;
2307 _flkeys = NULL;
2308 out:
2309 if (_flkeys) {
2310 keys->addrs.v6addrs.src = _flkeys->addrs.v6addrs.src;
2311 keys->addrs.v6addrs.dst = _flkeys->addrs.v6addrs.dst;
2312 keys->tags.flow_label = _flkeys->tags.flow_label;
2313 keys->basic.ip_proto = _flkeys->basic.ip_proto;
2314 } else {
2315 keys->addrs.v6addrs.src = key_iph->saddr;
2316 keys->addrs.v6addrs.dst = key_iph->daddr;
2317 keys->tags.flow_label = ip6_flowlabel(key_iph);
2318 keys->basic.ip_proto = key_iph->nexthdr;
2319 }
2320 }
2321
2322 /* if skb is set it will be used and fl6 can be NULL */
2323 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
2324 const struct sk_buff *skb, struct flow_keys *flkeys)
2325 {
2326 struct flow_keys hash_keys;
2327 u32 mhash;
2328
2329 switch (ip6_multipath_hash_policy(net)) {
2330 case 0:
2331 memset(&hash_keys, 0, sizeof(hash_keys));
2332 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2333 if (skb) {
2334 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
2335 } else {
2336 hash_keys.addrs.v6addrs.src = fl6->saddr;
2337 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2338 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2339 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2340 }
2341 break;
2342 case 1:
2343 if (skb) {
2344 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
2345 struct flow_keys keys;
2346
2347 /* short-circuit if we already have L4 hash present */
2348 if (skb->l4_hash)
2349 return skb_get_hash_raw(skb) >> 1;
2350
2351 memset(&hash_keys, 0, sizeof(hash_keys));
2352
2353 if (!flkeys) {
2354 skb_flow_dissect_flow_keys(skb, &keys, flag);
2355 flkeys = &keys;
2356 }
2357 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2358 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2359 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2360 hash_keys.ports.src = flkeys->ports.src;
2361 hash_keys.ports.dst = flkeys->ports.dst;
2362 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2363 } else {
2364 memset(&hash_keys, 0, sizeof(hash_keys));
2365 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2366 hash_keys.addrs.v6addrs.src = fl6->saddr;
2367 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2368 hash_keys.ports.src = fl6->fl6_sport;
2369 hash_keys.ports.dst = fl6->fl6_dport;
2370 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2371 }
2372 break;
2373 case 2:
2374 memset(&hash_keys, 0, sizeof(hash_keys));
2375 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2376 if (skb) {
2377 struct flow_keys keys;
2378
2379 if (!flkeys) {
2380 skb_flow_dissect_flow_keys(skb, &keys, 0);
2381 flkeys = &keys;
2382 }
2383
2384 /* Inner can be v4 or v6 */
2385 if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) {
2386 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
2387 hash_keys.addrs.v4addrs.src = flkeys->addrs.v4addrs.src;
2388 hash_keys.addrs.v4addrs.dst = flkeys->addrs.v4addrs.dst;
2389 } else if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) {
2390 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2391 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2392 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2393 hash_keys.tags.flow_label = flkeys->tags.flow_label;
2394 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2395 } else {
2396 /* Same as case 0 */
2397 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2398 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
2399 }
2400 } else {
2401 /* Same as case 0 */
2402 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2403 hash_keys.addrs.v6addrs.src = fl6->saddr;
2404 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2405 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2406 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2407 }
2408 break;
2409 }
2410 mhash = flow_hash_from_keys(&hash_keys);
2411
2412 return mhash >> 1;
2413 }
2414
2415 /* Called with rcu held */
2416 void ip6_route_input(struct sk_buff *skb)
2417 {
2418 const struct ipv6hdr *iph = ipv6_hdr(skb);
2419 struct net *net = dev_net(skb->dev);
2420 int flags = RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_DST_NOREF;
2421 struct ip_tunnel_info *tun_info;
2422 struct flowi6 fl6 = {
2423 .flowi6_iif = skb->dev->ifindex,
2424 .daddr = iph->daddr,
2425 .saddr = iph->saddr,
2426 .flowlabel = ip6_flowinfo(iph),
2427 .flowi6_mark = skb->mark,
2428 .flowi6_proto = iph->nexthdr,
2429 };
2430 struct flow_keys *flkeys = NULL, _flkeys;
2431
2432 tun_info = skb_tunnel_info(skb);
2433 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
2434 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
2435
2436 if (fib6_rules_early_flow_dissect(net, skb, &fl6, &_flkeys))
2437 flkeys = &_flkeys;
2438
2439 if (unlikely(fl6.flowi6_proto == IPPROTO_ICMPV6))
2440 fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, flkeys);
2441 skb_dst_drop(skb);
2442 skb_dst_set_noref(skb, ip6_route_input_lookup(net, skb->dev,
2443 &fl6, skb, flags));
2444 }
2445
2446 static struct rt6_info *ip6_pol_route_output(struct net *net,
2447 struct fib6_table *table,
2448 struct flowi6 *fl6,
2449 const struct sk_buff *skb,
2450 int flags)
2451 {
2452 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, skb, flags);
2453 }
2454
2455 struct dst_entry *ip6_route_output_flags_noref(struct net *net,
2456 const struct sock *sk,
2457 struct flowi6 *fl6, int flags)
2458 {
2459 bool any_src;
2460
2461 if (ipv6_addr_type(&fl6->daddr) &
2462 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL)) {
2463 struct dst_entry *dst;
2464
2465 /* This function does not take refcnt on the dst */
2466 dst = l3mdev_link_scope_lookup(net, fl6);
2467 if (dst)
2468 return dst;
2469 }
2470
2471 fl6->flowi6_iif = LOOPBACK_IFINDEX;
2472
2473 flags |= RT6_LOOKUP_F_DST_NOREF;
2474 any_src = ipv6_addr_any(&fl6->saddr);
2475 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
2476 (fl6->flowi6_oif && any_src))
2477 flags |= RT6_LOOKUP_F_IFACE;
2478
2479 if (!any_src)
2480 flags |= RT6_LOOKUP_F_HAS_SADDR;
2481 else if (sk)
2482 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
2483
2484 return fib6_rule_lookup(net, fl6, NULL, flags, ip6_pol_route_output);
2485 }
2486 EXPORT_SYMBOL_GPL(ip6_route_output_flags_noref);
2487
2488 struct dst_entry *ip6_route_output_flags(struct net *net,
2489 const struct sock *sk,
2490 struct flowi6 *fl6,
2491 int flags)
2492 {
2493 struct dst_entry *dst;
2494 struct rt6_info *rt6;
2495
2496 rcu_read_lock();
2497 dst = ip6_route_output_flags_noref(net, sk, fl6, flags);
2498 rt6 = (struct rt6_info *)dst;
2499 /* For dst cached in uncached_list, refcnt is already taken. */
2500 if (list_empty(&rt6->rt6i_uncached) && !dst_hold_safe(dst)) {
2501 dst = &net->ipv6.ip6_null_entry->dst;
2502 dst_hold(dst);
2503 }
2504 rcu_read_unlock();
2505
2506 return dst;
2507 }
2508 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
2509
2510 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2511 {
2512 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
2513 struct net_device *loopback_dev = net->loopback_dev;
2514 struct dst_entry *new = NULL;
2515
2516 rt = dst_alloc(&ip6_dst_blackhole_ops, loopback_dev, 1,
2517 DST_OBSOLETE_DEAD, 0);
2518 if (rt) {
2519 rt6_info_init(rt);
2520 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
2521
2522 new = &rt->dst;
2523 new->__use = 1;
2524 new->input = dst_discard;
2525 new->output = dst_discard_out;
2526
2527 dst_copy_metrics(new, &ort->dst);
2528
2529 rt->rt6i_idev = in6_dev_get(loopback_dev);
2530 rt->rt6i_gateway = ort->rt6i_gateway;
2531 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
2532
2533 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
2534 #ifdef CONFIG_IPV6_SUBTREES
2535 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
2536 #endif
2537 }
2538
2539 dst_release(dst_orig);
2540 return new ? new : ERR_PTR(-ENOMEM);
2541 }
2542
2543 /*
2544 * Destination cache support functions
2545 */
2546
2547 static bool fib6_check(struct fib6_info *f6i, u32 cookie)
2548 {
2549 u32 rt_cookie = 0;
2550
2551 if (!fib6_get_cookie_safe(f6i, &rt_cookie) || rt_cookie != cookie)
2552 return false;
2553
2554 if (fib6_check_expired(f6i))
2555 return false;
2556
2557 return true;
2558 }
2559
2560 static struct dst_entry *rt6_check(struct rt6_info *rt,
2561 struct fib6_info *from,
2562 u32 cookie)
2563 {
2564 u32 rt_cookie = 0;
2565
2566 if (!from || !fib6_get_cookie_safe(from, &rt_cookie) ||
2567 rt_cookie != cookie)
2568 return NULL;
2569
2570 if (rt6_check_expired(rt))
2571 return NULL;
2572
2573 return &rt->dst;
2574 }
2575
2576 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt,
2577 struct fib6_info *from,
2578 u32 cookie)
2579 {
2580 if (!__rt6_check_expired(rt) &&
2581 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
2582 fib6_check(from, cookie))
2583 return &rt->dst;
2584 else
2585 return NULL;
2586 }
2587
2588 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
2589 {
2590 struct dst_entry *dst_ret;
2591 struct fib6_info *from;
2592 struct rt6_info *rt;
2593
2594 rt = container_of(dst, struct rt6_info, dst);
2595
2596 rcu_read_lock();
2597
2598 /* All IPV6 dsts are created with ->obsolete set to the value
2599 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
2600 * into this function always.
2601 */
2602
2603 from = rcu_dereference(rt->from);
2604
2605 if (from && (rt->rt6i_flags & RTF_PCPU ||
2606 unlikely(!list_empty(&rt->rt6i_uncached))))
2607 dst_ret = rt6_dst_from_check(rt, from, cookie);
2608 else
2609 dst_ret = rt6_check(rt, from, cookie);
2610
2611 rcu_read_unlock();
2612
2613 return dst_ret;
2614 }
2615
2616 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
2617 {
2618 struct rt6_info *rt = (struct rt6_info *) dst;
2619
2620 if (rt) {
2621 if (rt->rt6i_flags & RTF_CACHE) {
2622 rcu_read_lock();
2623 if (rt6_check_expired(rt)) {
2624 rt6_remove_exception_rt(rt);
2625 dst = NULL;
2626 }
2627 rcu_read_unlock();
2628 } else {
2629 dst_release(dst);
2630 dst = NULL;
2631 }
2632 }
2633 return dst;
2634 }
2635
2636 static void ip6_link_failure(struct sk_buff *skb)
2637 {
2638 struct rt6_info *rt;
2639
2640 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
2641
2642 rt = (struct rt6_info *) skb_dst(skb);
2643 if (rt) {
2644 rcu_read_lock();
2645 if (rt->rt6i_flags & RTF_CACHE) {
2646 rt6_remove_exception_rt(rt);
2647 } else {
2648 struct fib6_info *from;
2649 struct fib6_node *fn;
2650
2651 from = rcu_dereference(rt->from);
2652 if (from) {
2653 fn = rcu_dereference(from->fib6_node);
2654 if (fn && (rt->rt6i_flags & RTF_DEFAULT))
2655 fn->fn_sernum = -1;
2656 }
2657 }
2658 rcu_read_unlock();
2659 }
2660 }
2661
2662 static void rt6_update_expires(struct rt6_info *rt0, int timeout)
2663 {
2664 if (!(rt0->rt6i_flags & RTF_EXPIRES)) {
2665 struct fib6_info *from;
2666
2667 rcu_read_lock();
2668 from = rcu_dereference(rt0->from);
2669 if (from)
2670 rt0->dst.expires = from->expires;
2671 rcu_read_unlock();
2672 }
2673
2674 dst_set_expires(&rt0->dst, timeout);
2675 rt0->rt6i_flags |= RTF_EXPIRES;
2676 }
2677
2678 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
2679 {
2680 struct net *net = dev_net(rt->dst.dev);
2681
2682 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
2683 rt->rt6i_flags |= RTF_MODIFIED;
2684 rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
2685 }
2686
2687 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
2688 {
2689 return !(rt->rt6i_flags & RTF_CACHE) &&
2690 (rt->rt6i_flags & RTF_PCPU || rcu_access_pointer(rt->from));
2691 }
2692
2693 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
2694 const struct ipv6hdr *iph, u32 mtu)
2695 {
2696 const struct in6_addr *daddr, *saddr;
2697 struct rt6_info *rt6 = (struct rt6_info *)dst;
2698
2699 if (dst_metric_locked(dst, RTAX_MTU))
2700 return;
2701
2702 if (iph) {
2703 daddr = &iph->daddr;
2704 saddr = &iph->saddr;
2705 } else if (sk) {
2706 daddr = &sk->sk_v6_daddr;
2707 saddr = &inet6_sk(sk)->saddr;
2708 } else {
2709 daddr = NULL;
2710 saddr = NULL;
2711 }
2712 dst_confirm_neigh(dst, daddr);
2713 mtu = max_t(u32, mtu, IPV6_MIN_MTU);
2714 if (mtu >= dst_mtu(dst))
2715 return;
2716
2717 if (!rt6_cache_allowed_for_pmtu(rt6)) {
2718 rt6_do_update_pmtu(rt6, mtu);
2719 /* update rt6_ex->stamp for cache */
2720 if (rt6->rt6i_flags & RTF_CACHE)
2721 rt6_update_exception_stamp_rt(rt6);
2722 } else if (daddr) {
2723 struct fib6_result res = {};
2724 struct rt6_info *nrt6;
2725
2726 rcu_read_lock();
2727 res.f6i = rcu_dereference(rt6->from);
2728 if (!res.f6i)
2729 goto out_unlock;
2730
2731 res.fib6_flags = res.f6i->fib6_flags;
2732 res.fib6_type = res.f6i->fib6_type;
2733
2734 if (res.f6i->nh) {
2735 struct fib6_nh_match_arg arg = {
2736 .dev = dst->dev,
2737 .gw = &rt6->rt6i_gateway,
2738 };
2739
2740 nexthop_for_each_fib6_nh(res.f6i->nh,
2741 fib6_nh_find_match, &arg);
2742
2743 /* fib6_info uses a nexthop that does not have fib6_nh
2744 * using the dst->dev + gw. Should be impossible.
2745 */
2746 if (!arg.match)
2747 goto out_unlock;
2748
2749 res.nh = arg.match;
2750 } else {
2751 res.nh = res.f6i->fib6_nh;
2752 }
2753
2754 nrt6 = ip6_rt_cache_alloc(&res, daddr, saddr);
2755 if (nrt6) {
2756 rt6_do_update_pmtu(nrt6, mtu);
2757 if (rt6_insert_exception(nrt6, &res))
2758 dst_release_immediate(&nrt6->dst);
2759 }
2760 out_unlock:
2761 rcu_read_unlock();
2762 }
2763 }
2764
2765 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
2766 struct sk_buff *skb, u32 mtu)
2767 {
2768 __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
2769 }
2770
2771 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
2772 int oif, u32 mark, kuid_t uid)
2773 {
2774 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2775 struct dst_entry *dst;
2776 struct flowi6 fl6 = {
2777 .flowi6_oif = oif,
2778 .flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark),
2779 .daddr = iph->daddr,
2780 .saddr = iph->saddr,
2781 .flowlabel = ip6_flowinfo(iph),
2782 .flowi6_uid = uid,
2783 };
2784
2785 dst = ip6_route_output(net, NULL, &fl6);
2786 if (!dst->error)
2787 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
2788 dst_release(dst);
2789 }
2790 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
2791
2792 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
2793 {
2794 int oif = sk->sk_bound_dev_if;
2795 struct dst_entry *dst;
2796
2797 if (!oif && skb->dev)
2798 oif = l3mdev_master_ifindex(skb->dev);
2799
2800 ip6_update_pmtu(skb, sock_net(sk), mtu, oif, sk->sk_mark, sk->sk_uid);
2801
2802 dst = __sk_dst_get(sk);
2803 if (!dst || !dst->obsolete ||
2804 dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
2805 return;
2806
2807 bh_lock_sock(sk);
2808 if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
2809 ip6_datagram_dst_update(sk, false);
2810 bh_unlock_sock(sk);
2811 }
2812 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
2813
2814 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
2815 const struct flowi6 *fl6)
2816 {
2817 #ifdef CONFIG_IPV6_SUBTREES
2818 struct ipv6_pinfo *np = inet6_sk(sk);
2819 #endif
2820
2821 ip6_dst_store(sk, dst,
2822 ipv6_addr_equal(&fl6->daddr, &sk->sk_v6_daddr) ?
2823 &sk->sk_v6_daddr : NULL,
2824 #ifdef CONFIG_IPV6_SUBTREES
2825 ipv6_addr_equal(&fl6->saddr, &np->saddr) ?
2826 &np->saddr :
2827 #endif
2828 NULL);
2829 }
2830
2831 static bool ip6_redirect_nh_match(const struct fib6_result *res,
2832 struct flowi6 *fl6,
2833 const struct in6_addr *gw,
2834 struct rt6_info **ret)
2835 {
2836 const struct fib6_nh *nh = res->nh;
2837
2838 if (nh->fib_nh_flags & RTNH_F_DEAD || !nh->fib_nh_gw_family ||
2839 fl6->flowi6_oif != nh->fib_nh_dev->ifindex)
2840 return false;
2841
2842 /* rt_cache's gateway might be different from its 'parent'
2843 * in the case of an ip redirect.
2844 * So we keep searching in the exception table if the gateway
2845 * is different.
2846 */
2847 if (!ipv6_addr_equal(gw, &nh->fib_nh_gw6)) {
2848 struct rt6_info *rt_cache;
2849
2850 rt_cache = rt6_find_cached_rt(res, &fl6->daddr, &fl6->saddr);
2851 if (rt_cache &&
2852 ipv6_addr_equal(gw, &rt_cache->rt6i_gateway)) {
2853 *ret = rt_cache;
2854 return true;
2855 }
2856 return false;
2857 }
2858 return true;
2859 }
2860
2861 struct fib6_nh_rd_arg {
2862 struct fib6_result *res;
2863 struct flowi6 *fl6;
2864 const struct in6_addr *gw;
2865 struct rt6_info **ret;
2866 };
2867
2868 static int fib6_nh_redirect_match(struct fib6_nh *nh, void *_arg)
2869 {
2870 struct fib6_nh_rd_arg *arg = _arg;
2871
2872 arg->res->nh = nh;
2873 return ip6_redirect_nh_match(arg->res, arg->fl6, arg->gw, arg->ret);
2874 }
2875
2876 /* Handle redirects */
2877 struct ip6rd_flowi {
2878 struct flowi6 fl6;
2879 struct in6_addr gateway;
2880 };
2881
2882 static struct rt6_info *__ip6_route_redirect(struct net *net,
2883 struct fib6_table *table,
2884 struct flowi6 *fl6,
2885 const struct sk_buff *skb,
2886 int flags)
2887 {
2888 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
2889 struct rt6_info *ret = NULL;
2890 struct fib6_result res = {};
2891 struct fib6_nh_rd_arg arg = {
2892 .res = &res,
2893 .fl6 = fl6,
2894 .gw = &rdfl->gateway,
2895 .ret = &ret
2896 };
2897 struct fib6_info *rt;
2898 struct fib6_node *fn;
2899
2900 /* l3mdev_update_flow overrides oif if the device is enslaved; in
2901 * this case we must match on the real ingress device, so reset it
2902 */
2903 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
2904 fl6->flowi6_oif = skb->dev->ifindex;
2905
2906 /* Get the "current" route for this destination and
2907 * check if the redirect has come from appropriate router.
2908 *
2909 * RFC 4861 specifies that redirects should only be
2910 * accepted if they come from the nexthop to the target.
2911 * Due to the way the routes are chosen, this notion
2912 * is a bit fuzzy and one might need to check all possible
2913 * routes.
2914 */
2915
2916 rcu_read_lock();
2917 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
2918 restart:
2919 for_each_fib6_node_rt_rcu(fn) {
2920 res.f6i = rt;
2921 if (fib6_check_expired(rt))
2922 continue;
2923 if (rt->fib6_flags & RTF_REJECT)
2924 break;
2925 if (unlikely(rt->nh)) {
2926 if (nexthop_is_blackhole(rt->nh))
2927 continue;
2928 /* on match, res->nh is filled in and potentially ret */
2929 if (nexthop_for_each_fib6_nh(rt->nh,
2930 fib6_nh_redirect_match,
2931 &arg))
2932 goto out;
2933 } else {
2934 res.nh = rt->fib6_nh;
2935 if (ip6_redirect_nh_match(&res, fl6, &rdfl->gateway,
2936 &ret))
2937 goto out;
2938 }
2939 }
2940
2941 if (!rt)
2942 rt = net->ipv6.fib6_null_entry;
2943 else if (rt->fib6_flags & RTF_REJECT) {
2944 ret = net->ipv6.ip6_null_entry;
2945 goto out;
2946 }
2947
2948 if (rt == net->ipv6.fib6_null_entry) {
2949 fn = fib6_backtrack(fn, &fl6->saddr);
2950 if (fn)
2951 goto restart;
2952 }
2953
2954 res.f6i = rt;
2955 res.nh = rt->fib6_nh;
2956 out:
2957 if (ret) {
2958 ip6_hold_safe(net, &ret);
2959 } else {
2960 res.fib6_flags = res.f6i->fib6_flags;
2961 res.fib6_type = res.f6i->fib6_type;
2962 ret = ip6_create_rt_rcu(&res);
2963 }
2964
2965 rcu_read_unlock();
2966
2967 trace_fib6_table_lookup(net, &res, table, fl6);
2968 return ret;
2969 };
2970
2971 static struct dst_entry *ip6_route_redirect(struct net *net,
2972 const struct flowi6 *fl6,
2973 const struct sk_buff *skb,
2974 const struct in6_addr *gateway)
2975 {
2976 int flags = RT6_LOOKUP_F_HAS_SADDR;
2977 struct ip6rd_flowi rdfl;
2978
2979 rdfl.fl6 = *fl6;
2980 rdfl.gateway = *gateway;
2981
2982 return fib6_rule_lookup(net, &rdfl.fl6, skb,
2983 flags, __ip6_route_redirect);
2984 }
2985
2986 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
2987 kuid_t uid)
2988 {
2989 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2990 struct dst_entry *dst;
2991 struct flowi6 fl6 = {
2992 .flowi6_iif = LOOPBACK_IFINDEX,
2993 .flowi6_oif = oif,
2994 .flowi6_mark = mark,
2995 .daddr = iph->daddr,
2996 .saddr = iph->saddr,
2997 .flowlabel = ip6_flowinfo(iph),
2998 .flowi6_uid = uid,
2999 };
3000
3001 dst = ip6_route_redirect(net, &fl6, skb, &ipv6_hdr(skb)->saddr);
3002 rt6_do_redirect(dst, NULL, skb);
3003 dst_release(dst);
3004 }
3005 EXPORT_SYMBOL_GPL(ip6_redirect);
3006
3007 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif)
3008 {
3009 const struct ipv6hdr *iph = ipv6_hdr(skb);
3010 const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
3011 struct dst_entry *dst;
3012 struct flowi6 fl6 = {
3013 .flowi6_iif = LOOPBACK_IFINDEX,
3014 .flowi6_oif = oif,
3015 .daddr = msg->dest,
3016 .saddr = iph->daddr,
3017 .flowi6_uid = sock_net_uid(net, NULL),
3018 };
3019
3020 dst = ip6_route_redirect(net, &fl6, skb, &iph->saddr);
3021 rt6_do_redirect(dst, NULL, skb);
3022 dst_release(dst);
3023 }
3024
3025 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
3026 {
3027 ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark,
3028 sk->sk_uid);
3029 }
3030 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
3031
3032 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
3033 {
3034 struct net_device *dev = dst->dev;
3035 unsigned int mtu = dst_mtu(dst);
3036 struct net *net = dev_net(dev);
3037
3038 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
3039
3040 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
3041 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
3042
3043 /*
3044 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
3045 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
3046 * IPV6_MAXPLEN is also valid and means: "any MSS,
3047 * rely only on pmtu discovery"
3048 */
3049 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
3050 mtu = IPV6_MAXPLEN;
3051 return mtu;
3052 }
3053
3054 static unsigned int ip6_mtu(const struct dst_entry *dst)
3055 {
3056 struct inet6_dev *idev;
3057 unsigned int mtu;
3058
3059 mtu = dst_metric_raw(dst, RTAX_MTU);
3060 if (mtu)
3061 goto out;
3062
3063 mtu = IPV6_MIN_MTU;
3064
3065 rcu_read_lock();
3066 idev = __in6_dev_get(dst->dev);
3067 if (idev)
3068 mtu = idev->cnf.mtu6;
3069 rcu_read_unlock();
3070
3071 out:
3072 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
3073
3074 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
3075 }
3076
3077 /* MTU selection:
3078 * 1. mtu on route is locked - use it
3079 * 2. mtu from nexthop exception
3080 * 3. mtu from egress device
3081 *
3082 * based on ip6_dst_mtu_forward and exception logic of
3083 * rt6_find_cached_rt; called with rcu_read_lock
3084 */
3085 u32 ip6_mtu_from_fib6(const struct fib6_result *res,
3086 const struct in6_addr *daddr,
3087 const struct in6_addr *saddr)
3088 {
3089 const struct fib6_nh *nh = res->nh;
3090 struct fib6_info *f6i = res->f6i;
3091 struct inet6_dev *idev;
3092 struct rt6_info *rt;
3093 u32 mtu = 0;
3094
3095 if (unlikely(fib6_metric_locked(f6i, RTAX_MTU))) {
3096 mtu = f6i->fib6_pmtu;
3097 if (mtu)
3098 goto out;
3099 }
3100
3101 rt = rt6_find_cached_rt(res, daddr, saddr);
3102 if (unlikely(rt)) {
3103 mtu = dst_metric_raw(&rt->dst, RTAX_MTU);
3104 } else {
3105 struct net_device *dev = nh->fib_nh_dev;
3106
3107 mtu = IPV6_MIN_MTU;
3108 idev = __in6_dev_get(dev);
3109 if (idev && idev->cnf.mtu6 > mtu)
3110 mtu = idev->cnf.mtu6;
3111 }
3112
3113 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
3114 out:
3115 return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
3116 }
3117
3118 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
3119 struct flowi6 *fl6)
3120 {
3121 struct dst_entry *dst;
3122 struct rt6_info *rt;
3123 struct inet6_dev *idev = in6_dev_get(dev);
3124 struct net *net = dev_net(dev);
3125
3126 if (unlikely(!idev))
3127 return ERR_PTR(-ENODEV);
3128
3129 rt = ip6_dst_alloc(net, dev, 0);
3130 if (unlikely(!rt)) {
3131 in6_dev_put(idev);
3132 dst = ERR_PTR(-ENOMEM);
3133 goto out;
3134 }
3135
3136 rt->dst.flags |= DST_HOST;
3137 rt->dst.input = ip6_input;
3138 rt->dst.output = ip6_output;
3139 rt->rt6i_gateway = fl6->daddr;
3140 rt->rt6i_dst.addr = fl6->daddr;
3141 rt->rt6i_dst.plen = 128;
3142 rt->rt6i_idev = idev;
3143 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
3144
3145 /* Add this dst into uncached_list so that rt6_disable_ip() can
3146 * do proper release of the net_device
3147 */
3148 rt6_uncached_list_add(rt);
3149 atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
3150
3151 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
3152
3153 out:
3154 return dst;
3155 }
3156
3157 static int ip6_dst_gc(struct dst_ops *ops)
3158 {
3159 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
3160 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
3161 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
3162 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
3163 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
3164 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
3165 int entries;
3166
3167 entries = dst_entries_get_fast(ops);
3168 if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
3169 entries <= rt_max_size)
3170 goto out;
3171
3172 net->ipv6.ip6_rt_gc_expire++;
3173 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
3174 entries = dst_entries_get_slow(ops);
3175 if (entries < ops->gc_thresh)
3176 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
3177 out:
3178 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
3179 return entries > rt_max_size;
3180 }
3181
3182 static int ip6_nh_lookup_table(struct net *net, struct fib6_config *cfg,
3183 const struct in6_addr *gw_addr, u32 tbid,
3184 int flags, struct fib6_result *res)
3185 {
3186 struct flowi6 fl6 = {
3187 .flowi6_oif = cfg->fc_ifindex,
3188 .daddr = *gw_addr,
3189 .saddr = cfg->fc_prefsrc,
3190 };
3191 struct fib6_table *table;
3192 int err;
3193
3194 table = fib6_get_table(net, tbid);
3195 if (!table)
3196 return -EINVAL;
3197
3198 if (!ipv6_addr_any(&cfg->fc_prefsrc))
3199 flags |= RT6_LOOKUP_F_HAS_SADDR;
3200
3201 flags |= RT6_LOOKUP_F_IGNORE_LINKSTATE;
3202
3203 err = fib6_table_lookup(net, table, cfg->fc_ifindex, &fl6, res, flags);
3204 if (!err && res->f6i != net->ipv6.fib6_null_entry)
3205 fib6_select_path(net, res, &fl6, cfg->fc_ifindex,
3206 cfg->fc_ifindex != 0, NULL, flags);
3207
3208 return err;
3209 }
3210
3211 static int ip6_route_check_nh_onlink(struct net *net,
3212 struct fib6_config *cfg,
3213 const struct net_device *dev,
3214 struct netlink_ext_ack *extack)
3215 {
3216 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
3217 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3218 struct fib6_result res = {};
3219 int err;
3220
3221 err = ip6_nh_lookup_table(net, cfg, gw_addr, tbid, 0, &res);
3222 if (!err && !(res.fib6_flags & RTF_REJECT) &&
3223 /* ignore match if it is the default route */
3224 !ipv6_addr_any(&res.f6i->fib6_dst.addr) &&
3225 (res.fib6_type != RTN_UNICAST || dev != res.nh->fib_nh_dev)) {
3226 NL_SET_ERR_MSG(extack,
3227 "Nexthop has invalid gateway or device mismatch");
3228 err = -EINVAL;
3229 }
3230
3231 return err;
3232 }
3233
3234 static int ip6_route_check_nh(struct net *net,
3235 struct fib6_config *cfg,
3236 struct net_device **_dev,
3237 struct inet6_dev **idev)
3238 {
3239 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3240 struct net_device *dev = _dev ? *_dev : NULL;
3241 int flags = RT6_LOOKUP_F_IFACE;
3242 struct fib6_result res = {};
3243 int err = -EHOSTUNREACH;
3244
3245 if (cfg->fc_table) {
3246 err = ip6_nh_lookup_table(net, cfg, gw_addr,
3247 cfg->fc_table, flags, &res);
3248 /* gw_addr can not require a gateway or resolve to a reject
3249 * route. If a device is given, it must match the result.
3250 */
3251 if (err || res.fib6_flags & RTF_REJECT ||
3252 res.nh->fib_nh_gw_family ||
3253 (dev && dev != res.nh->fib_nh_dev))
3254 err = -EHOSTUNREACH;
3255 }
3256
3257 if (err < 0) {
3258 struct flowi6 fl6 = {
3259 .flowi6_oif = cfg->fc_ifindex,
3260 .daddr = *gw_addr,
3261 };
3262
3263 err = fib6_lookup(net, cfg->fc_ifindex, &fl6, &res, flags);
3264 if (err || res.fib6_flags & RTF_REJECT ||
3265 res.nh->fib_nh_gw_family)
3266 err = -EHOSTUNREACH;
3267
3268 if (err)
3269 return err;
3270
3271 fib6_select_path(net, &res, &fl6, cfg->fc_ifindex,
3272 cfg->fc_ifindex != 0, NULL, flags);
3273 }
3274
3275 err = 0;
3276 if (dev) {
3277 if (dev != res.nh->fib_nh_dev)
3278 err = -EHOSTUNREACH;
3279 } else {
3280 *_dev = dev = res.nh->fib_nh_dev;
3281 dev_hold(dev);
3282 *idev = in6_dev_get(dev);
3283 }
3284
3285 return err;
3286 }
3287
3288 static int ip6_validate_gw(struct net *net, struct fib6_config *cfg,
3289 struct net_device **_dev, struct inet6_dev **idev,
3290 struct netlink_ext_ack *extack)
3291 {
3292 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3293 int gwa_type = ipv6_addr_type(gw_addr);
3294 bool skip_dev = gwa_type & IPV6_ADDR_LINKLOCAL ? false : true;
3295 const struct net_device *dev = *_dev;
3296 bool need_addr_check = !dev;
3297 int err = -EINVAL;
3298
3299 /* if gw_addr is local we will fail to detect this in case
3300 * address is still TENTATIVE (DAD in progress). rt6_lookup()
3301 * will return already-added prefix route via interface that
3302 * prefix route was assigned to, which might be non-loopback.
3303 */
3304 if (dev &&
3305 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
3306 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
3307 goto out;
3308 }
3309
3310 if (gwa_type != (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST)) {
3311 /* IPv6 strictly inhibits using not link-local
3312 * addresses as nexthop address.
3313 * Otherwise, router will not able to send redirects.
3314 * It is very good, but in some (rare!) circumstances
3315 * (SIT, PtP, NBMA NOARP links) it is handy to allow
3316 * some exceptions. --ANK
3317 * We allow IPv4-mapped nexthops to support RFC4798-type
3318 * addressing
3319 */
3320 if (!(gwa_type & (IPV6_ADDR_UNICAST | IPV6_ADDR_MAPPED))) {
3321 NL_SET_ERR_MSG(extack, "Invalid gateway address");
3322 goto out;
3323 }
3324
3325 rcu_read_lock();
3326
3327 if (cfg->fc_flags & RTNH_F_ONLINK)
3328 err = ip6_route_check_nh_onlink(net, cfg, dev, extack);
3329 else
3330 err = ip6_route_check_nh(net, cfg, _dev, idev);
3331
3332 rcu_read_unlock();
3333
3334 if (err)
3335 goto out;
3336 }
3337
3338 /* reload in case device was changed */
3339 dev = *_dev;
3340
3341 err = -EINVAL;
3342 if (!dev) {
3343 NL_SET_ERR_MSG(extack, "Egress device not specified");
3344 goto out;
3345 } else if (dev->flags & IFF_LOOPBACK) {
3346 NL_SET_ERR_MSG(extack,
3347 "Egress device can not be loopback device for this route");
3348 goto out;
3349 }
3350
3351 /* if we did not check gw_addr above, do so now that the
3352 * egress device has been resolved.
3353 */
3354 if (need_addr_check &&
3355 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
3356 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
3357 goto out;
3358 }
3359
3360 err = 0;
3361 out:
3362 return err;
3363 }
3364
3365 static bool fib6_is_reject(u32 flags, struct net_device *dev, int addr_type)
3366 {
3367 if ((flags & RTF_REJECT) ||
3368 (dev && (dev->flags & IFF_LOOPBACK) &&
3369 !(addr_type & IPV6_ADDR_LOOPBACK) &&
3370 !(flags & RTF_LOCAL)))
3371 return true;
3372
3373 return false;
3374 }
3375
3376 int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
3377 struct fib6_config *cfg, gfp_t gfp_flags,
3378 struct netlink_ext_ack *extack)
3379 {
3380 struct net_device *dev = NULL;
3381 struct inet6_dev *idev = NULL;
3382 int addr_type;
3383 int err;
3384
3385 fib6_nh->fib_nh_family = AF_INET6;
3386
3387 err = -ENODEV;
3388 if (cfg->fc_ifindex) {
3389 dev = dev_get_by_index(net, cfg->fc_ifindex);
3390 if (!dev)
3391 goto out;
3392 idev = in6_dev_get(dev);
3393 if (!idev)
3394 goto out;
3395 }
3396
3397 if (cfg->fc_flags & RTNH_F_ONLINK) {
3398 if (!dev) {
3399 NL_SET_ERR_MSG(extack,
3400 "Nexthop device required for onlink");
3401 goto out;
3402 }
3403
3404 if (!(dev->flags & IFF_UP)) {
3405 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3406 err = -ENETDOWN;
3407 goto out;
3408 }
3409
3410 fib6_nh->fib_nh_flags |= RTNH_F_ONLINK;
3411 }
3412
3413 fib6_nh->fib_nh_weight = 1;
3414
3415 /* We cannot add true routes via loopback here,
3416 * they would result in kernel looping; promote them to reject routes
3417 */
3418 addr_type = ipv6_addr_type(&cfg->fc_dst);
3419 if (fib6_is_reject(cfg->fc_flags, dev, addr_type)) {
3420 /* hold loopback dev/idev if we haven't done so. */
3421 if (dev != net->loopback_dev) {
3422 if (dev) {
3423 dev_put(dev);
3424 in6_dev_put(idev);
3425 }
3426 dev = net->loopback_dev;
3427 dev_hold(dev);
3428 idev = in6_dev_get(dev);
3429 if (!idev) {
3430 err = -ENODEV;
3431 goto out;
3432 }
3433 }
3434 goto pcpu_alloc;
3435 }
3436
3437 if (cfg->fc_flags & RTF_GATEWAY) {
3438 err = ip6_validate_gw(net, cfg, &dev, &idev, extack);
3439 if (err)
3440 goto out;
3441
3442 fib6_nh->fib_nh_gw6 = cfg->fc_gateway;
3443 fib6_nh->fib_nh_gw_family = AF_INET6;
3444 }
3445
3446 err = -ENODEV;
3447 if (!dev)
3448 goto out;
3449
3450 if (idev->cnf.disable_ipv6) {
3451 NL_SET_ERR_MSG(extack, "IPv6 is disabled on nexthop device");
3452 err = -EACCES;
3453 goto out;
3454 }
3455
3456 if (!(dev->flags & IFF_UP) && !cfg->fc_ignore_dev_down) {
3457 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3458 err = -ENETDOWN;
3459 goto out;
3460 }
3461
3462 if (!(cfg->fc_flags & (RTF_LOCAL | RTF_ANYCAST)) &&
3463 !netif_carrier_ok(dev))
3464 fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
3465
3466 err = fib_nh_common_init(&fib6_nh->nh_common, cfg->fc_encap,
3467 cfg->fc_encap_type, cfg, gfp_flags, extack);
3468 if (err)
3469 goto out;
3470
3471 pcpu_alloc:
3472 fib6_nh->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, gfp_flags);
3473 if (!fib6_nh->rt6i_pcpu) {
3474 err = -ENOMEM;
3475 goto out;
3476 }
3477
3478 fib6_nh->fib_nh_dev = dev;
3479 fib6_nh->fib_nh_oif = dev->ifindex;
3480 err = 0;
3481 out:
3482 if (idev)
3483 in6_dev_put(idev);
3484
3485 if (err) {
3486 lwtstate_put(fib6_nh->fib_nh_lws);
3487 fib6_nh->fib_nh_lws = NULL;
3488 if (dev)
3489 dev_put(dev);
3490 }
3491
3492 return err;
3493 }
3494
3495 void fib6_nh_release(struct fib6_nh *fib6_nh)
3496 {
3497 struct rt6_exception_bucket *bucket;
3498
3499 rcu_read_lock();
3500
3501 fib6_nh_flush_exceptions(fib6_nh, NULL);
3502 bucket = fib6_nh_get_excptn_bucket(fib6_nh, NULL);
3503 if (bucket) {
3504 rcu_assign_pointer(fib6_nh->rt6i_exception_bucket, NULL);
3505 kfree(bucket);
3506 }
3507
3508 rcu_read_unlock();
3509
3510 if (fib6_nh->rt6i_pcpu) {
3511 int cpu;
3512
3513 for_each_possible_cpu(cpu) {
3514 struct rt6_info **ppcpu_rt;
3515 struct rt6_info *pcpu_rt;
3516
3517 ppcpu_rt = per_cpu_ptr(fib6_nh->rt6i_pcpu, cpu);
3518 pcpu_rt = *ppcpu_rt;
3519 if (pcpu_rt) {
3520 dst_dev_put(&pcpu_rt->dst);
3521 dst_release(&pcpu_rt->dst);
3522 *ppcpu_rt = NULL;
3523 }
3524 }
3525
3526 free_percpu(fib6_nh->rt6i_pcpu);
3527 }
3528
3529 fib_nh_common_release(&fib6_nh->nh_common);
3530 }
3531
3532 static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg,
3533 gfp_t gfp_flags,
3534 struct netlink_ext_ack *extack)
3535 {
3536 struct net *net = cfg->fc_nlinfo.nl_net;
3537 struct fib6_info *rt = NULL;
3538 struct nexthop *nh = NULL;
3539 struct fib6_table *table;
3540 struct fib6_nh *fib6_nh;
3541 int err = -EINVAL;
3542 int addr_type;
3543
3544 /* RTF_PCPU is an internal flag; can not be set by userspace */
3545 if (cfg->fc_flags & RTF_PCPU) {
3546 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_PCPU");
3547 goto out;
3548 }
3549
3550 /* RTF_CACHE is an internal flag; can not be set by userspace */
3551 if (cfg->fc_flags & RTF_CACHE) {
3552 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_CACHE");
3553 goto out;
3554 }
3555
3556 if (cfg->fc_type > RTN_MAX) {
3557 NL_SET_ERR_MSG(extack, "Invalid route type");
3558 goto out;
3559 }
3560
3561 if (cfg->fc_dst_len > 128) {
3562 NL_SET_ERR_MSG(extack, "Invalid prefix length");
3563 goto out;
3564 }
3565 if (cfg->fc_src_len > 128) {
3566 NL_SET_ERR_MSG(extack, "Invalid source address length");
3567 goto out;
3568 }
3569 #ifndef CONFIG_IPV6_SUBTREES
3570 if (cfg->fc_src_len) {
3571 NL_SET_ERR_MSG(extack,
3572 "Specifying source address requires IPV6_SUBTREES to be enabled");
3573 goto out;
3574 }
3575 #endif
3576 if (cfg->fc_nh_id) {
3577 nh = nexthop_find_by_id(net, cfg->fc_nh_id);
3578 if (!nh) {
3579 NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
3580 goto out;
3581 }
3582 err = fib6_check_nexthop(nh, cfg, extack);
3583 if (err)
3584 goto out;
3585 }
3586
3587 err = -ENOBUFS;
3588 if (cfg->fc_nlinfo.nlh &&
3589 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
3590 table = fib6_get_table(net, cfg->fc_table);
3591 if (!table) {
3592 pr_warn("NLM_F_CREATE should be specified when creating new route\n");
3593 table = fib6_new_table(net, cfg->fc_table);
3594 }
3595 } else {
3596 table = fib6_new_table(net, cfg->fc_table);
3597 }
3598
3599 if (!table)
3600 goto out;
3601
3602 err = -ENOMEM;
3603 rt = fib6_info_alloc(gfp_flags, !nh);
3604 if (!rt)
3605 goto out;
3606
3607 rt->fib6_metrics = ip_fib_metrics_init(net, cfg->fc_mx, cfg->fc_mx_len,
3608 extack);
3609 if (IS_ERR(rt->fib6_metrics)) {
3610 err = PTR_ERR(rt->fib6_metrics);
3611 /* Do not leave garbage there. */
3612 rt->fib6_metrics = (struct dst_metrics *)&dst_default_metrics;
3613 goto out;
3614 }
3615
3616 if (cfg->fc_flags & RTF_ADDRCONF)
3617 rt->dst_nocount = true;
3618
3619 if (cfg->fc_flags & RTF_EXPIRES)
3620 fib6_set_expires(rt, jiffies +
3621 clock_t_to_jiffies(cfg->fc_expires));
3622 else
3623 fib6_clean_expires(rt);
3624
3625 if (cfg->fc_protocol == RTPROT_UNSPEC)
3626 cfg->fc_protocol = RTPROT_BOOT;
3627 rt->fib6_protocol = cfg->fc_protocol;
3628
3629 rt->fib6_table = table;
3630 rt->fib6_metric = cfg->fc_metric;
3631 rt->fib6_type = cfg->fc_type ? : RTN_UNICAST;
3632 rt->fib6_flags = cfg->fc_flags & ~RTF_GATEWAY;
3633
3634 ipv6_addr_prefix(&rt->fib6_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
3635 rt->fib6_dst.plen = cfg->fc_dst_len;
3636 if (rt->fib6_dst.plen == 128)
3637 rt->dst_host = true;
3638
3639 #ifdef CONFIG_IPV6_SUBTREES
3640 ipv6_addr_prefix(&rt->fib6_src.addr, &cfg->fc_src, cfg->fc_src_len);
3641 rt->fib6_src.plen = cfg->fc_src_len;
3642 #endif
3643 if (nh) {
3644 if (!nexthop_get(nh)) {
3645 NL_SET_ERR_MSG(extack, "Nexthop has been deleted");
3646 goto out;
3647 }
3648 if (rt->fib6_src.plen) {
3649 NL_SET_ERR_MSG(extack, "Nexthops can not be used with source routing");
3650 goto out;
3651 }
3652 rt->nh = nh;
3653 fib6_nh = nexthop_fib6_nh(rt->nh);
3654 } else {
3655 err = fib6_nh_init(net, rt->fib6_nh, cfg, gfp_flags, extack);
3656 if (err)
3657 goto out;
3658
3659 fib6_nh = rt->fib6_nh;
3660
3661 /* We cannot add true routes via loopback here, they would
3662 * result in kernel looping; promote them to reject routes
3663 */
3664 addr_type = ipv6_addr_type(&cfg->fc_dst);
3665 if (fib6_is_reject(cfg->fc_flags, rt->fib6_nh->fib_nh_dev,
3666 addr_type))
3667 rt->fib6_flags = RTF_REJECT | RTF_NONEXTHOP;
3668 }
3669
3670 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
3671 struct net_device *dev = fib6_nh->fib_nh_dev;
3672
3673 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
3674 NL_SET_ERR_MSG(extack, "Invalid source address");
3675 err = -EINVAL;
3676 goto out;
3677 }
3678 rt->fib6_prefsrc.addr = cfg->fc_prefsrc;
3679 rt->fib6_prefsrc.plen = 128;
3680 } else
3681 rt->fib6_prefsrc.plen = 0;
3682
3683 return rt;
3684 out:
3685 fib6_info_release(rt);
3686 return ERR_PTR(err);
3687 }
3688
3689 int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
3690 struct netlink_ext_ack *extack)
3691 {
3692 struct fib6_info *rt;
3693 int err;
3694
3695 rt = ip6_route_info_create(cfg, gfp_flags, extack);
3696 if (IS_ERR(rt))
3697 return PTR_ERR(rt);
3698
3699 err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack);
3700 fib6_info_release(rt);
3701
3702 return err;
3703 }
3704
3705 static int __ip6_del_rt(struct fib6_info *rt, struct nl_info *info)
3706 {
3707 struct net *net = info->nl_net;
3708 struct fib6_table *table;
3709 int err;
3710
3711 if (rt == net->ipv6.fib6_null_entry) {
3712 err = -ENOENT;
3713 goto out;
3714 }
3715
3716 table = rt->fib6_table;
3717 spin_lock_bh(&table->tb6_lock);
3718 err = fib6_del(rt, info);
3719 spin_unlock_bh(&table->tb6_lock);
3720
3721 out:
3722 fib6_info_release(rt);
3723 return err;
3724 }
3725
3726 int ip6_del_rt(struct net *net, struct fib6_info *rt)
3727 {
3728 struct nl_info info = { .nl_net = net };
3729
3730 return __ip6_del_rt(rt, &info);
3731 }
3732
3733 static int __ip6_del_rt_siblings(struct fib6_info *rt, struct fib6_config *cfg)
3734 {
3735 struct nl_info *info = &cfg->fc_nlinfo;
3736 struct net *net = info->nl_net;
3737 struct sk_buff *skb = NULL;
3738 struct fib6_table *table;
3739 int err = -ENOENT;
3740
3741 if (rt == net->ipv6.fib6_null_entry)
3742 goto out_put;
3743 table = rt->fib6_table;
3744 spin_lock_bh(&table->tb6_lock);
3745
3746 if (rt->fib6_nsiblings && cfg->fc_delete_all_nh) {
3747 struct fib6_info *sibling, *next_sibling;
3748
3749 /* prefer to send a single notification with all hops */
3750 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3751 if (skb) {
3752 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3753
3754 if (rt6_fill_node(net, skb, rt, NULL,
3755 NULL, NULL, 0, RTM_DELROUTE,
3756 info->portid, seq, 0) < 0) {
3757 kfree_skb(skb);
3758 skb = NULL;
3759 } else
3760 info->skip_notify = 1;
3761 }
3762
3763 info->skip_notify_kernel = 1;
3764 call_fib6_multipath_entry_notifiers(net,
3765 FIB_EVENT_ENTRY_DEL,
3766 rt,
3767 rt->fib6_nsiblings,
3768 NULL);
3769 list_for_each_entry_safe(sibling, next_sibling,
3770 &rt->fib6_siblings,
3771 fib6_siblings) {
3772 err = fib6_del(sibling, info);
3773 if (err)
3774 goto out_unlock;
3775 }
3776 }
3777
3778 err = fib6_del(rt, info);
3779 out_unlock:
3780 spin_unlock_bh(&table->tb6_lock);
3781 out_put:
3782 fib6_info_release(rt);
3783
3784 if (skb) {
3785 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3786 info->nlh, gfp_any());
3787 }
3788 return err;
3789 }
3790
3791 static int __ip6_del_cached_rt(struct rt6_info *rt, struct fib6_config *cfg)
3792 {
3793 int rc = -ESRCH;
3794
3795 if (cfg->fc_ifindex && rt->dst.dev->ifindex != cfg->fc_ifindex)
3796 goto out;
3797
3798 if (cfg->fc_flags & RTF_GATEWAY &&
3799 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
3800 goto out;
3801
3802 rc = rt6_remove_exception_rt(rt);
3803 out:
3804 return rc;
3805 }
3806
3807 static int ip6_del_cached_rt(struct fib6_config *cfg, struct fib6_info *rt,
3808 struct fib6_nh *nh)
3809 {
3810 struct fib6_result res = {
3811 .f6i = rt,
3812 .nh = nh,
3813 };
3814 struct rt6_info *rt_cache;
3815
3816 rt_cache = rt6_find_cached_rt(&res, &cfg->fc_dst, &cfg->fc_src);
3817 if (rt_cache)
3818 return __ip6_del_cached_rt(rt_cache, cfg);
3819
3820 return 0;
3821 }
3822
3823 struct fib6_nh_del_cached_rt_arg {
3824 struct fib6_config *cfg;
3825 struct fib6_info *f6i;
3826 };
3827
3828 static int fib6_nh_del_cached_rt(struct fib6_nh *nh, void *_arg)
3829 {
3830 struct fib6_nh_del_cached_rt_arg *arg = _arg;
3831 int rc;
3832
3833 rc = ip6_del_cached_rt(arg->cfg, arg->f6i, nh);
3834 return rc != -ESRCH ? rc : 0;
3835 }
3836
3837 static int ip6_del_cached_rt_nh(struct fib6_config *cfg, struct fib6_info *f6i)
3838 {
3839 struct fib6_nh_del_cached_rt_arg arg = {
3840 .cfg = cfg,
3841 .f6i = f6i
3842 };
3843
3844 return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_del_cached_rt, &arg);
3845 }
3846
3847 static int ip6_route_del(struct fib6_config *cfg,
3848 struct netlink_ext_ack *extack)
3849 {
3850 struct fib6_table *table;
3851 struct fib6_info *rt;
3852 struct fib6_node *fn;
3853 int err = -ESRCH;
3854
3855 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
3856 if (!table) {
3857 NL_SET_ERR_MSG(extack, "FIB table does not exist");
3858 return err;
3859 }
3860
3861 rcu_read_lock();
3862
3863 fn = fib6_locate(&table->tb6_root,
3864 &cfg->fc_dst, cfg->fc_dst_len,
3865 &cfg->fc_src, cfg->fc_src_len,
3866 !(cfg->fc_flags & RTF_CACHE));
3867
3868 if (fn) {
3869 for_each_fib6_node_rt_rcu(fn) {
3870 struct fib6_nh *nh;
3871
3872 if (rt->nh && cfg->fc_nh_id &&
3873 rt->nh->id != cfg->fc_nh_id)
3874 continue;
3875
3876 if (cfg->fc_flags & RTF_CACHE) {
3877 int rc = 0;
3878
3879 if (rt->nh) {
3880 rc = ip6_del_cached_rt_nh(cfg, rt);
3881 } else if (cfg->fc_nh_id) {
3882 continue;
3883 } else {
3884 nh = rt->fib6_nh;
3885 rc = ip6_del_cached_rt(cfg, rt, nh);
3886 }
3887 if (rc != -ESRCH) {
3888 rcu_read_unlock();
3889 return rc;
3890 }
3891 continue;
3892 }
3893
3894 if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
3895 continue;
3896 if (cfg->fc_protocol &&
3897 cfg->fc_protocol != rt->fib6_protocol)
3898 continue;
3899
3900 if (rt->nh) {
3901 if (!fib6_info_hold_safe(rt))
3902 continue;
3903 rcu_read_unlock();
3904
3905 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
3906 }
3907 if (cfg->fc_nh_id)
3908 continue;
3909
3910 nh = rt->fib6_nh;
3911 if (cfg->fc_ifindex &&
3912 (!nh->fib_nh_dev ||
3913 nh->fib_nh_dev->ifindex != cfg->fc_ifindex))
3914 continue;
3915 if (cfg->fc_flags & RTF_GATEWAY &&
3916 !ipv6_addr_equal(&cfg->fc_gateway, &nh->fib_nh_gw6))
3917 continue;
3918 if (!fib6_info_hold_safe(rt))
3919 continue;
3920 rcu_read_unlock();
3921
3922 /* if gateway was specified only delete the one hop */
3923 if (cfg->fc_flags & RTF_GATEWAY)
3924 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
3925
3926 return __ip6_del_rt_siblings(rt, cfg);
3927 }
3928 }
3929 rcu_read_unlock();
3930
3931 return err;
3932 }
3933
3934 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
3935 {
3936 struct netevent_redirect netevent;
3937 struct rt6_info *rt, *nrt = NULL;
3938 struct fib6_result res = {};
3939 struct ndisc_options ndopts;
3940 struct inet6_dev *in6_dev;
3941 struct neighbour *neigh;
3942 struct rd_msg *msg;
3943 int optlen, on_link;
3944 u8 *lladdr;
3945
3946 optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
3947 optlen -= sizeof(*msg);
3948
3949 if (optlen < 0) {
3950 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
3951 return;
3952 }
3953
3954 msg = (struct rd_msg *)icmp6_hdr(skb);
3955
3956 if (ipv6_addr_is_multicast(&msg->dest)) {
3957 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
3958 return;
3959 }
3960
3961 on_link = 0;
3962 if (ipv6_addr_equal(&msg->dest, &msg->target)) {
3963 on_link = 1;
3964 } else if (ipv6_addr_type(&msg->target) !=
3965 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
3966 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
3967 return;
3968 }
3969
3970 in6_dev = __in6_dev_get(skb->dev);
3971 if (!in6_dev)
3972 return;
3973 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
3974 return;
3975
3976 /* RFC2461 8.1:
3977 * The IP source address of the Redirect MUST be the same as the current
3978 * first-hop router for the specified ICMP Destination Address.
3979 */
3980
3981 if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
3982 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
3983 return;
3984 }
3985
3986 lladdr = NULL;
3987 if (ndopts.nd_opts_tgt_lladdr) {
3988 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
3989 skb->dev);
3990 if (!lladdr) {
3991 net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
3992 return;
3993 }
3994 }
3995
3996 rt = (struct rt6_info *) dst;
3997 if (rt->rt6i_flags & RTF_REJECT) {
3998 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
3999 return;
4000 }
4001
4002 /* Redirect received -> path was valid.
4003 * Look, redirects are sent only in response to data packets,
4004 * so that this nexthop apparently is reachable. --ANK
4005 */
4006 dst_confirm_neigh(&rt->dst, &ipv6_hdr(skb)->saddr);
4007
4008 neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
4009 if (!neigh)
4010 return;
4011
4012 /*
4013 * We have finally decided to accept it.
4014 */
4015
4016 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
4017 NEIGH_UPDATE_F_WEAK_OVERRIDE|
4018 NEIGH_UPDATE_F_OVERRIDE|
4019 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
4020 NEIGH_UPDATE_F_ISROUTER)),
4021 NDISC_REDIRECT, &ndopts);
4022
4023 rcu_read_lock();
4024 res.f6i = rcu_dereference(rt->from);
4025 if (!res.f6i)
4026 goto out;
4027
4028 if (res.f6i->nh) {
4029 struct fib6_nh_match_arg arg = {
4030 .dev = dst->dev,
4031 .gw = &rt->rt6i_gateway,
4032 };
4033
4034 nexthop_for_each_fib6_nh(res.f6i->nh,
4035 fib6_nh_find_match, &arg);
4036
4037 /* fib6_info uses a nexthop that does not have fib6_nh
4038 * using the dst->dev. Should be impossible
4039 */
4040 if (!arg.match)
4041 goto out;
4042 res.nh = arg.match;
4043 } else {
4044 res.nh = res.f6i->fib6_nh;
4045 }
4046
4047 res.fib6_flags = res.f6i->fib6_flags;
4048 res.fib6_type = res.f6i->fib6_type;
4049 nrt = ip6_rt_cache_alloc(&res, &msg->dest, NULL);
4050 if (!nrt)
4051 goto out;
4052
4053 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
4054 if (on_link)
4055 nrt->rt6i_flags &= ~RTF_GATEWAY;
4056
4057 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
4058
4059 /* rt6_insert_exception() will take care of duplicated exceptions */
4060 if (rt6_insert_exception(nrt, &res)) {
4061 dst_release_immediate(&nrt->dst);
4062 goto out;
4063 }
4064
4065 netevent.old = &rt->dst;
4066 netevent.new = &nrt->dst;
4067 netevent.daddr = &msg->dest;
4068 netevent.neigh = neigh;
4069 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
4070
4071 out:
4072 rcu_read_unlock();
4073 neigh_release(neigh);
4074 }
4075
4076 #ifdef CONFIG_IPV6_ROUTE_INFO
4077 static struct fib6_info *rt6_get_route_info(struct net *net,
4078 const struct in6_addr *prefix, int prefixlen,
4079 const struct in6_addr *gwaddr,
4080 struct net_device *dev)
4081 {
4082 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
4083 int ifindex = dev->ifindex;
4084 struct fib6_node *fn;
4085 struct fib6_info *rt = NULL;
4086 struct fib6_table *table;
4087
4088 table = fib6_get_table(net, tb_id);
4089 if (!table)
4090 return NULL;
4091
4092 rcu_read_lock();
4093 fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0, true);
4094 if (!fn)
4095 goto out;
4096
4097 for_each_fib6_node_rt_rcu(fn) {
4098 /* these routes do not use nexthops */
4099 if (rt->nh)
4100 continue;
4101 if (rt->fib6_nh->fib_nh_dev->ifindex != ifindex)
4102 continue;
4103 if (!(rt->fib6_flags & RTF_ROUTEINFO) ||
4104 !rt->fib6_nh->fib_nh_gw_family)
4105 continue;
4106 if (!ipv6_addr_equal(&rt->fib6_nh->fib_nh_gw6, gwaddr))
4107 continue;
4108 if (!fib6_info_hold_safe(rt))
4109 continue;
4110 break;
4111 }
4112 out:
4113 rcu_read_unlock();
4114 return rt;
4115 }
4116
4117 static struct fib6_info *rt6_add_route_info(struct net *net,
4118 const struct in6_addr *prefix, int prefixlen,
4119 const struct in6_addr *gwaddr,
4120 struct net_device *dev,
4121 unsigned int pref)
4122 {
4123 struct fib6_config cfg = {
4124 .fc_metric = IP6_RT_PRIO_USER,
4125 .fc_ifindex = dev->ifindex,
4126 .fc_dst_len = prefixlen,
4127 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
4128 RTF_UP | RTF_PREF(pref),
4129 .fc_protocol = RTPROT_RA,
4130 .fc_type = RTN_UNICAST,
4131 .fc_nlinfo.portid = 0,
4132 .fc_nlinfo.nlh = NULL,
4133 .fc_nlinfo.nl_net = net,
4134 };
4135
4136 cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO,
4137 cfg.fc_dst = *prefix;
4138 cfg.fc_gateway = *gwaddr;
4139
4140 /* We should treat it as a default route if prefix length is 0. */
4141 if (!prefixlen)
4142 cfg.fc_flags |= RTF_DEFAULT;
4143
4144 ip6_route_add(&cfg, GFP_ATOMIC, NULL);
4145
4146 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
4147 }
4148 #endif
4149
4150 struct fib6_info *rt6_get_dflt_router(struct net *net,
4151 const struct in6_addr *addr,
4152 struct net_device *dev)
4153 {
4154 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT;
4155 struct fib6_info *rt;
4156 struct fib6_table *table;
4157
4158 table = fib6_get_table(net, tb_id);
4159 if (!table)
4160 return NULL;
4161
4162 rcu_read_lock();
4163 for_each_fib6_node_rt_rcu(&table->tb6_root) {
4164 struct fib6_nh *nh;
4165
4166 /* RA routes do not use nexthops */
4167 if (rt->nh)
4168 continue;
4169
4170 nh = rt->fib6_nh;
4171 if (dev == nh->fib_nh_dev &&
4172 ((rt->fib6_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
4173 ipv6_addr_equal(&nh->fib_nh_gw6, addr))
4174 break;
4175 }
4176 if (rt && !fib6_info_hold_safe(rt))
4177 rt = NULL;
4178 rcu_read_unlock();
4179 return rt;
4180 }
4181
4182 struct fib6_info *rt6_add_dflt_router(struct net *net,
4183 const struct in6_addr *gwaddr,
4184 struct net_device *dev,
4185 unsigned int pref)
4186 {
4187 struct fib6_config cfg = {
4188 .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
4189 .fc_metric = IP6_RT_PRIO_USER,
4190 .fc_ifindex = dev->ifindex,
4191 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
4192 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
4193 .fc_protocol = RTPROT_RA,
4194 .fc_type = RTN_UNICAST,
4195 .fc_nlinfo.portid = 0,
4196 .fc_nlinfo.nlh = NULL,
4197 .fc_nlinfo.nl_net = net,
4198 };
4199
4200 cfg.fc_gateway = *gwaddr;
4201
4202 if (!ip6_route_add(&cfg, GFP_ATOMIC, NULL)) {
4203 struct fib6_table *table;
4204
4205 table = fib6_get_table(dev_net(dev), cfg.fc_table);
4206 if (table)
4207 table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
4208 }
4209
4210 return rt6_get_dflt_router(net, gwaddr, dev);
4211 }
4212
4213 static void __rt6_purge_dflt_routers(struct net *net,
4214 struct fib6_table *table)
4215 {
4216 struct fib6_info *rt;
4217
4218 restart:
4219 rcu_read_lock();
4220 for_each_fib6_node_rt_rcu(&table->tb6_root) {
4221 struct net_device *dev = fib6_info_nh_dev(rt);
4222 struct inet6_dev *idev = dev ? __in6_dev_get(dev) : NULL;
4223
4224 if (rt->fib6_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
4225 (!idev || idev->cnf.accept_ra != 2) &&
4226 fib6_info_hold_safe(rt)) {
4227 rcu_read_unlock();
4228 ip6_del_rt(net, rt);
4229 goto restart;
4230 }
4231 }
4232 rcu_read_unlock();
4233
4234 table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
4235 }
4236
4237 void rt6_purge_dflt_routers(struct net *net)
4238 {
4239 struct fib6_table *table;
4240 struct hlist_head *head;
4241 unsigned int h;
4242
4243 rcu_read_lock();
4244
4245 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
4246 head = &net->ipv6.fib_table_hash[h];
4247 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
4248 if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
4249 __rt6_purge_dflt_routers(net, table);
4250 }
4251 }
4252
4253 rcu_read_unlock();
4254 }
4255
4256 static void rtmsg_to_fib6_config(struct net *net,
4257 struct in6_rtmsg *rtmsg,
4258 struct fib6_config *cfg)
4259 {
4260 *cfg = (struct fib6_config){
4261 .fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
4262 : RT6_TABLE_MAIN,
4263 .fc_ifindex = rtmsg->rtmsg_ifindex,
4264 .fc_metric = rtmsg->rtmsg_metric ? : IP6_RT_PRIO_USER,
4265 .fc_expires = rtmsg->rtmsg_info,
4266 .fc_dst_len = rtmsg->rtmsg_dst_len,
4267 .fc_src_len = rtmsg->rtmsg_src_len,
4268 .fc_flags = rtmsg->rtmsg_flags,
4269 .fc_type = rtmsg->rtmsg_type,
4270
4271 .fc_nlinfo.nl_net = net,
4272
4273 .fc_dst = rtmsg->rtmsg_dst,
4274 .fc_src = rtmsg->rtmsg_src,
4275 .fc_gateway = rtmsg->rtmsg_gateway,
4276 };
4277 }
4278
4279 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
4280 {
4281 struct fib6_config cfg;
4282 struct in6_rtmsg rtmsg;
4283 int err;
4284
4285 switch (cmd) {
4286 case SIOCADDRT: /* Add a route */
4287 case SIOCDELRT: /* Delete a route */
4288 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
4289 return -EPERM;
4290 err = copy_from_user(&rtmsg, arg,
4291 sizeof(struct in6_rtmsg));
4292 if (err)
4293 return -EFAULT;
4294
4295 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
4296
4297 rtnl_lock();
4298 switch (cmd) {
4299 case SIOCADDRT:
4300 err = ip6_route_add(&cfg, GFP_KERNEL, NULL);
4301 break;
4302 case SIOCDELRT:
4303 err = ip6_route_del(&cfg, NULL);
4304 break;
4305 default:
4306 err = -EINVAL;
4307 }
4308 rtnl_unlock();
4309
4310 return err;
4311 }
4312
4313 return -EINVAL;
4314 }
4315
4316 /*
4317 * Drop the packet on the floor
4318 */
4319
4320 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
4321 {
4322 struct dst_entry *dst = skb_dst(skb);
4323 struct net *net = dev_net(dst->dev);
4324 struct inet6_dev *idev;
4325 int type;
4326
4327 if (netif_is_l3_master(skb->dev) &&
4328 dst->dev == net->loopback_dev)
4329 idev = __in6_dev_get_safely(dev_get_by_index_rcu(net, IP6CB(skb)->iif));
4330 else
4331 idev = ip6_dst_idev(dst);
4332
4333 switch (ipstats_mib_noroutes) {
4334 case IPSTATS_MIB_INNOROUTES:
4335 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
4336 if (type == IPV6_ADDR_ANY) {
4337 IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
4338 break;
4339 }
4340 /* FALLTHROUGH */
4341 case IPSTATS_MIB_OUTNOROUTES:
4342 IP6_INC_STATS(net, idev, ipstats_mib_noroutes);
4343 break;
4344 }
4345
4346 /* Start over by dropping the dst for l3mdev case */
4347 if (netif_is_l3_master(skb->dev))
4348 skb_dst_drop(skb);
4349
4350 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
4351 kfree_skb(skb);
4352 return 0;
4353 }
4354
4355 static int ip6_pkt_discard(struct sk_buff *skb)
4356 {
4357 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
4358 }
4359
4360 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
4361 {
4362 skb->dev = skb_dst(skb)->dev;
4363 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
4364 }
4365
4366 static int ip6_pkt_prohibit(struct sk_buff *skb)
4367 {
4368 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
4369 }
4370
4371 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
4372 {
4373 skb->dev = skb_dst(skb)->dev;
4374 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
4375 }
4376
4377 /*
4378 * Allocate a dst for local (unicast / anycast) address.
4379 */
4380
4381 struct fib6_info *addrconf_f6i_alloc(struct net *net,
4382 struct inet6_dev *idev,
4383 const struct in6_addr *addr,
4384 bool anycast, gfp_t gfp_flags)
4385 {
4386 struct fib6_config cfg = {
4387 .fc_table = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL,
4388 .fc_ifindex = idev->dev->ifindex,
4389 .fc_flags = RTF_UP | RTF_NONEXTHOP,
4390 .fc_dst = *addr,
4391 .fc_dst_len = 128,
4392 .fc_protocol = RTPROT_KERNEL,
4393 .fc_nlinfo.nl_net = net,
4394 .fc_ignore_dev_down = true,
4395 };
4396 struct fib6_info *f6i;
4397
4398 if (anycast) {
4399 cfg.fc_type = RTN_ANYCAST;
4400 cfg.fc_flags |= RTF_ANYCAST;
4401 } else {
4402 cfg.fc_type = RTN_LOCAL;
4403 cfg.fc_flags |= RTF_LOCAL;
4404 }
4405
4406 f6i = ip6_route_info_create(&cfg, gfp_flags, NULL);
4407 if (!IS_ERR(f6i))
4408 f6i->dst_nocount = true;
4409 return f6i;
4410 }
4411
4412 /* remove deleted ip from prefsrc entries */
4413 struct arg_dev_net_ip {
4414 struct net_device *dev;
4415 struct net *net;
4416 struct in6_addr *addr;
4417 };
4418
4419 static int fib6_remove_prefsrc(struct fib6_info *rt, void *arg)
4420 {
4421 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
4422 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
4423 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
4424
4425 if (!rt->nh &&
4426 ((void *)rt->fib6_nh->fib_nh_dev == dev || !dev) &&
4427 rt != net->ipv6.fib6_null_entry &&
4428 ipv6_addr_equal(addr, &rt->fib6_prefsrc.addr)) {
4429 spin_lock_bh(&rt6_exception_lock);
4430 /* remove prefsrc entry */
4431 rt->fib6_prefsrc.plen = 0;
4432 spin_unlock_bh(&rt6_exception_lock);
4433 }
4434 return 0;
4435 }
4436
4437 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
4438 {
4439 struct net *net = dev_net(ifp->idev->dev);
4440 struct arg_dev_net_ip adni = {
4441 .dev = ifp->idev->dev,
4442 .net = net,
4443 .addr = &ifp->addr,
4444 };
4445 fib6_clean_all(net, fib6_remove_prefsrc, &adni);
4446 }
4447
4448 #define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT)
4449
4450 /* Remove routers and update dst entries when gateway turn into host. */
4451 static int fib6_clean_tohost(struct fib6_info *rt, void *arg)
4452 {
4453 struct in6_addr *gateway = (struct in6_addr *)arg;
4454 struct fib6_nh *nh;
4455
4456 /* RA routes do not use nexthops */
4457 if (rt->nh)
4458 return 0;
4459
4460 nh = rt->fib6_nh;
4461 if (((rt->fib6_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) &&
4462 nh->fib_nh_gw_family && ipv6_addr_equal(gateway, &nh->fib_nh_gw6))
4463 return -1;
4464
4465 /* Further clean up cached routes in exception table.
4466 * This is needed because cached route may have a different
4467 * gateway than its 'parent' in the case of an ip redirect.
4468 */
4469 fib6_nh_exceptions_clean_tohost(nh, gateway);
4470
4471 return 0;
4472 }
4473
4474 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
4475 {
4476 fib6_clean_all(net, fib6_clean_tohost, gateway);
4477 }
4478
4479 struct arg_netdev_event {
4480 const struct net_device *dev;
4481 union {
4482 unsigned char nh_flags;
4483 unsigned long event;
4484 };
4485 };
4486
4487 static struct fib6_info *rt6_multipath_first_sibling(const struct fib6_info *rt)
4488 {
4489 struct fib6_info *iter;
4490 struct fib6_node *fn;
4491
4492 fn = rcu_dereference_protected(rt->fib6_node,
4493 lockdep_is_held(&rt->fib6_table->tb6_lock));
4494 iter = rcu_dereference_protected(fn->leaf,
4495 lockdep_is_held(&rt->fib6_table->tb6_lock));
4496 while (iter) {
4497 if (iter->fib6_metric == rt->fib6_metric &&
4498 rt6_qualify_for_ecmp(iter))
4499 return iter;
4500 iter = rcu_dereference_protected(iter->fib6_next,
4501 lockdep_is_held(&rt->fib6_table->tb6_lock));
4502 }
4503
4504 return NULL;
4505 }
4506
4507 /* only called for fib entries with builtin fib6_nh */
4508 static bool rt6_is_dead(const struct fib6_info *rt)
4509 {
4510 if (rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD ||
4511 (rt->fib6_nh->fib_nh_flags & RTNH_F_LINKDOWN &&
4512 ip6_ignore_linkdown(rt->fib6_nh->fib_nh_dev)))
4513 return true;
4514
4515 return false;
4516 }
4517
4518 static int rt6_multipath_total_weight(const struct fib6_info *rt)
4519 {
4520 struct fib6_info *iter;
4521 int total = 0;
4522
4523 if (!rt6_is_dead(rt))
4524 total += rt->fib6_nh->fib_nh_weight;
4525
4526 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
4527 if (!rt6_is_dead(iter))
4528 total += iter->fib6_nh->fib_nh_weight;
4529 }
4530
4531 return total;
4532 }
4533
4534 static void rt6_upper_bound_set(struct fib6_info *rt, int *weight, int total)
4535 {
4536 int upper_bound = -1;
4537
4538 if (!rt6_is_dead(rt)) {
4539 *weight += rt->fib6_nh->fib_nh_weight;
4540 upper_bound = DIV_ROUND_CLOSEST_ULL((u64) (*weight) << 31,
4541 total) - 1;
4542 }
4543 atomic_set(&rt->fib6_nh->fib_nh_upper_bound, upper_bound);
4544 }
4545
4546 static void rt6_multipath_upper_bound_set(struct fib6_info *rt, int total)
4547 {
4548 struct fib6_info *iter;
4549 int weight = 0;
4550
4551 rt6_upper_bound_set(rt, &weight, total);
4552
4553 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4554 rt6_upper_bound_set(iter, &weight, total);
4555 }
4556
4557 void rt6_multipath_rebalance(struct fib6_info *rt)
4558 {
4559 struct fib6_info *first;
4560 int total;
4561
4562 /* In case the entire multipath route was marked for flushing,
4563 * then there is no need to rebalance upon the removal of every
4564 * sibling route.
4565 */
4566 if (!rt->fib6_nsiblings || rt->should_flush)
4567 return;
4568
4569 /* During lookup routes are evaluated in order, so we need to
4570 * make sure upper bounds are assigned from the first sibling
4571 * onwards.
4572 */
4573 first = rt6_multipath_first_sibling(rt);
4574 if (WARN_ON_ONCE(!first))
4575 return;
4576
4577 total = rt6_multipath_total_weight(first);
4578 rt6_multipath_upper_bound_set(first, total);
4579 }
4580
4581 static int fib6_ifup(struct fib6_info *rt, void *p_arg)
4582 {
4583 const struct arg_netdev_event *arg = p_arg;
4584 struct net *net = dev_net(arg->dev);
4585
4586 if (rt != net->ipv6.fib6_null_entry && !rt->nh &&
4587 rt->fib6_nh->fib_nh_dev == arg->dev) {
4588 rt->fib6_nh->fib_nh_flags &= ~arg->nh_flags;
4589 fib6_update_sernum_upto_root(net, rt);
4590 rt6_multipath_rebalance(rt);
4591 }
4592
4593 return 0;
4594 }
4595
4596 void rt6_sync_up(struct net_device *dev, unsigned char nh_flags)
4597 {
4598 struct arg_netdev_event arg = {
4599 .dev = dev,
4600 {
4601 .nh_flags = nh_flags,
4602 },
4603 };
4604
4605 if (nh_flags & RTNH_F_DEAD && netif_carrier_ok(dev))
4606 arg.nh_flags |= RTNH_F_LINKDOWN;
4607
4608 fib6_clean_all(dev_net(dev), fib6_ifup, &arg);
4609 }
4610
4611 /* only called for fib entries with inline fib6_nh */
4612 static bool rt6_multipath_uses_dev(const struct fib6_info *rt,
4613 const struct net_device *dev)
4614 {
4615 struct fib6_info *iter;
4616
4617 if (rt->fib6_nh->fib_nh_dev == dev)
4618 return true;
4619 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4620 if (iter->fib6_nh->fib_nh_dev == dev)
4621 return true;
4622
4623 return false;
4624 }
4625
4626 static void rt6_multipath_flush(struct fib6_info *rt)
4627 {
4628 struct fib6_info *iter;
4629
4630 rt->should_flush = 1;
4631 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4632 iter->should_flush = 1;
4633 }
4634
4635 static unsigned int rt6_multipath_dead_count(const struct fib6_info *rt,
4636 const struct net_device *down_dev)
4637 {
4638 struct fib6_info *iter;
4639 unsigned int dead = 0;
4640
4641 if (rt->fib6_nh->fib_nh_dev == down_dev ||
4642 rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD)
4643 dead++;
4644 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4645 if (iter->fib6_nh->fib_nh_dev == down_dev ||
4646 iter->fib6_nh->fib_nh_flags & RTNH_F_DEAD)
4647 dead++;
4648
4649 return dead;
4650 }
4651
4652 static void rt6_multipath_nh_flags_set(struct fib6_info *rt,
4653 const struct net_device *dev,
4654 unsigned char nh_flags)
4655 {
4656 struct fib6_info *iter;
4657
4658 if (rt->fib6_nh->fib_nh_dev == dev)
4659 rt->fib6_nh->fib_nh_flags |= nh_flags;
4660 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4661 if (iter->fib6_nh->fib_nh_dev == dev)
4662 iter->fib6_nh->fib_nh_flags |= nh_flags;
4663 }
4664
4665 /* called with write lock held for table with rt */
4666 static int fib6_ifdown(struct fib6_info *rt, void *p_arg)
4667 {
4668 const struct arg_netdev_event *arg = p_arg;
4669 const struct net_device *dev = arg->dev;
4670 struct net *net = dev_net(dev);
4671
4672 if (rt == net->ipv6.fib6_null_entry || rt->nh)
4673 return 0;
4674
4675 switch (arg->event) {
4676 case NETDEV_UNREGISTER:
4677 return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
4678 case NETDEV_DOWN:
4679 if (rt->should_flush)
4680 return -1;
4681 if (!rt->fib6_nsiblings)
4682 return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
4683 if (rt6_multipath_uses_dev(rt, dev)) {
4684 unsigned int count;
4685
4686 count = rt6_multipath_dead_count(rt, dev);
4687 if (rt->fib6_nsiblings + 1 == count) {
4688 rt6_multipath_flush(rt);
4689 return -1;
4690 }
4691 rt6_multipath_nh_flags_set(rt, dev, RTNH_F_DEAD |
4692 RTNH_F_LINKDOWN);
4693 fib6_update_sernum(net, rt);
4694 rt6_multipath_rebalance(rt);
4695 }
4696 return -2;
4697 case NETDEV_CHANGE:
4698 if (rt->fib6_nh->fib_nh_dev != dev ||
4699 rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST))
4700 break;
4701 rt->fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
4702 rt6_multipath_rebalance(rt);
4703 break;
4704 }
4705
4706 return 0;
4707 }
4708
4709 void rt6_sync_down_dev(struct net_device *dev, unsigned long event)
4710 {
4711 struct arg_netdev_event arg = {
4712 .dev = dev,
4713 {
4714 .event = event,
4715 },
4716 };
4717 struct net *net = dev_net(dev);
4718
4719 if (net->ipv6.sysctl.skip_notify_on_dev_down)
4720 fib6_clean_all_skip_notify(net, fib6_ifdown, &arg);
4721 else
4722 fib6_clean_all(net, fib6_ifdown, &arg);
4723 }
4724
4725 void rt6_disable_ip(struct net_device *dev, unsigned long event)
4726 {
4727 rt6_sync_down_dev(dev, event);
4728 rt6_uncached_list_flush_dev(dev_net(dev), dev);
4729 neigh_ifdown(&nd_tbl, dev);
4730 }
4731
4732 struct rt6_mtu_change_arg {
4733 struct net_device *dev;
4734 unsigned int mtu;
4735 struct fib6_info *f6i;
4736 };
4737
4738 static int fib6_nh_mtu_change(struct fib6_nh *nh, void *_arg)
4739 {
4740 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *)_arg;
4741 struct fib6_info *f6i = arg->f6i;
4742
4743 /* For administrative MTU increase, there is no way to discover
4744 * IPv6 PMTU increase, so PMTU increase should be updated here.
4745 * Since RFC 1981 doesn't include administrative MTU increase
4746 * update PMTU increase is a MUST. (i.e. jumbo frame)
4747 */
4748 if (nh->fib_nh_dev == arg->dev) {
4749 struct inet6_dev *idev = __in6_dev_get(arg->dev);
4750 u32 mtu = f6i->fib6_pmtu;
4751
4752 if (mtu >= arg->mtu ||
4753 (mtu < arg->mtu && mtu == idev->cnf.mtu6))
4754 fib6_metric_set(f6i, RTAX_MTU, arg->mtu);
4755
4756 spin_lock_bh(&rt6_exception_lock);
4757 rt6_exceptions_update_pmtu(idev, nh, arg->mtu);
4758 spin_unlock_bh(&rt6_exception_lock);
4759 }
4760
4761 return 0;
4762 }
4763
4764 static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg)
4765 {
4766 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
4767 struct inet6_dev *idev;
4768
4769 /* In IPv6 pmtu discovery is not optional,
4770 so that RTAX_MTU lock cannot disable it.
4771 We still use this lock to block changes
4772 caused by addrconf/ndisc.
4773 */
4774
4775 idev = __in6_dev_get(arg->dev);
4776 if (!idev)
4777 return 0;
4778
4779 if (fib6_metric_locked(f6i, RTAX_MTU))
4780 return 0;
4781
4782 arg->f6i = f6i;
4783 if (f6i->nh) {
4784 /* fib6_nh_mtu_change only returns 0, so this is safe */
4785 return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_mtu_change,
4786 arg);
4787 }
4788
4789 return fib6_nh_mtu_change(f6i->fib6_nh, arg);
4790 }
4791
4792 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
4793 {
4794 struct rt6_mtu_change_arg arg = {
4795 .dev = dev,
4796 .mtu = mtu,
4797 };
4798
4799 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
4800 }
4801
4802 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
4803 [RTA_UNSPEC] = { .strict_start_type = RTA_DPORT + 1 },
4804 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
4805 [RTA_PREFSRC] = { .len = sizeof(struct in6_addr) },
4806 [RTA_OIF] = { .type = NLA_U32 },
4807 [RTA_IIF] = { .type = NLA_U32 },
4808 [RTA_PRIORITY] = { .type = NLA_U32 },
4809 [RTA_METRICS] = { .type = NLA_NESTED },
4810 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
4811 [RTA_PREF] = { .type = NLA_U8 },
4812 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
4813 [RTA_ENCAP] = { .type = NLA_NESTED },
4814 [RTA_EXPIRES] = { .type = NLA_U32 },
4815 [RTA_UID] = { .type = NLA_U32 },
4816 [RTA_MARK] = { .type = NLA_U32 },
4817 [RTA_TABLE] = { .type = NLA_U32 },
4818 [RTA_IP_PROTO] = { .type = NLA_U8 },
4819 [RTA_SPORT] = { .type = NLA_U16 },
4820 [RTA_DPORT] = { .type = NLA_U16 },
4821 [RTA_NH_ID] = { .type = NLA_U32 },
4822 };
4823
4824 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
4825 struct fib6_config *cfg,
4826 struct netlink_ext_ack *extack)
4827 {
4828 struct rtmsg *rtm;
4829 struct nlattr *tb[RTA_MAX+1];
4830 unsigned int pref;
4831 int err;
4832
4833 err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
4834 rtm_ipv6_policy, extack);
4835 if (err < 0)
4836 goto errout;
4837
4838 err = -EINVAL;
4839 rtm = nlmsg_data(nlh);
4840
4841 *cfg = (struct fib6_config){
4842 .fc_table = rtm->rtm_table,
4843 .fc_dst_len = rtm->rtm_dst_len,
4844 .fc_src_len = rtm->rtm_src_len,
4845 .fc_flags = RTF_UP,
4846 .fc_protocol = rtm->rtm_protocol,
4847 .fc_type = rtm->rtm_type,
4848
4849 .fc_nlinfo.portid = NETLINK_CB(skb).portid,
4850 .fc_nlinfo.nlh = nlh,
4851 .fc_nlinfo.nl_net = sock_net(skb->sk),
4852 };
4853
4854 if (rtm->rtm_type == RTN_UNREACHABLE ||
4855 rtm->rtm_type == RTN_BLACKHOLE ||
4856 rtm->rtm_type == RTN_PROHIBIT ||
4857 rtm->rtm_type == RTN_THROW)
4858 cfg->fc_flags |= RTF_REJECT;
4859
4860 if (rtm->rtm_type == RTN_LOCAL)
4861 cfg->fc_flags |= RTF_LOCAL;
4862
4863 if (rtm->rtm_flags & RTM_F_CLONED)
4864 cfg->fc_flags |= RTF_CACHE;
4865
4866 cfg->fc_flags |= (rtm->rtm_flags & RTNH_F_ONLINK);
4867
4868 if (tb[RTA_NH_ID]) {
4869 if (tb[RTA_GATEWAY] || tb[RTA_OIF] ||
4870 tb[RTA_MULTIPATH] || tb[RTA_ENCAP]) {
4871 NL_SET_ERR_MSG(extack,
4872 "Nexthop specification and nexthop id are mutually exclusive");
4873 goto errout;
4874 }
4875 cfg->fc_nh_id = nla_get_u32(tb[RTA_NH_ID]);
4876 }
4877
4878 if (tb[RTA_GATEWAY]) {
4879 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
4880 cfg->fc_flags |= RTF_GATEWAY;
4881 }
4882 if (tb[RTA_VIA]) {
4883 NL_SET_ERR_MSG(extack, "IPv6 does not support RTA_VIA attribute");
4884 goto errout;
4885 }
4886
4887 if (tb[RTA_DST]) {
4888 int plen = (rtm->rtm_dst_len + 7) >> 3;
4889
4890 if (nla_len(tb[RTA_DST]) < plen)
4891 goto errout;
4892
4893 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
4894 }
4895
4896 if (tb[RTA_SRC]) {
4897 int plen = (rtm->rtm_src_len + 7) >> 3;
4898
4899 if (nla_len(tb[RTA_SRC]) < plen)
4900 goto errout;
4901
4902 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
4903 }
4904
4905 if (tb[RTA_PREFSRC])
4906 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
4907
4908 if (tb[RTA_OIF])
4909 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
4910
4911 if (tb[RTA_PRIORITY])
4912 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
4913
4914 if (tb[RTA_METRICS]) {
4915 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
4916 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
4917 }
4918
4919 if (tb[RTA_TABLE])
4920 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
4921
4922 if (tb[RTA_MULTIPATH]) {
4923 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
4924 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
4925
4926 err = lwtunnel_valid_encap_type_attr(cfg->fc_mp,
4927 cfg->fc_mp_len, extack);
4928 if (err < 0)
4929 goto errout;
4930 }
4931
4932 if (tb[RTA_PREF]) {
4933 pref = nla_get_u8(tb[RTA_PREF]);
4934 if (pref != ICMPV6_ROUTER_PREF_LOW &&
4935 pref != ICMPV6_ROUTER_PREF_HIGH)
4936 pref = ICMPV6_ROUTER_PREF_MEDIUM;
4937 cfg->fc_flags |= RTF_PREF(pref);
4938 }
4939
4940 if (tb[RTA_ENCAP])
4941 cfg->fc_encap = tb[RTA_ENCAP];
4942
4943 if (tb[RTA_ENCAP_TYPE]) {
4944 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
4945
4946 err = lwtunnel_valid_encap_type(cfg->fc_encap_type, extack);
4947 if (err < 0)
4948 goto errout;
4949 }
4950
4951 if (tb[RTA_EXPIRES]) {
4952 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
4953
4954 if (addrconf_finite_timeout(timeout)) {
4955 cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
4956 cfg->fc_flags |= RTF_EXPIRES;
4957 }
4958 }
4959
4960 err = 0;
4961 errout:
4962 return err;
4963 }
4964
4965 struct rt6_nh {
4966 struct fib6_info *fib6_info;
4967 struct fib6_config r_cfg;
4968 struct list_head next;
4969 };
4970
4971 static int ip6_route_info_append(struct net *net,
4972 struct list_head *rt6_nh_list,
4973 struct fib6_info *rt,
4974 struct fib6_config *r_cfg)
4975 {
4976 struct rt6_nh *nh;
4977 int err = -EEXIST;
4978
4979 list_for_each_entry(nh, rt6_nh_list, next) {
4980 /* check if fib6_info already exists */
4981 if (rt6_duplicate_nexthop(nh->fib6_info, rt))
4982 return err;
4983 }
4984
4985 nh = kzalloc(sizeof(*nh), GFP_KERNEL);
4986 if (!nh)
4987 return -ENOMEM;
4988 nh->fib6_info = rt;
4989 memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
4990 list_add_tail(&nh->next, rt6_nh_list);
4991
4992 return 0;
4993 }
4994
4995 static void ip6_route_mpath_notify(struct fib6_info *rt,
4996 struct fib6_info *rt_last,
4997 struct nl_info *info,
4998 __u16 nlflags)
4999 {
5000 /* if this is an APPEND route, then rt points to the first route
5001 * inserted and rt_last points to last route inserted. Userspace
5002 * wants a consistent dump of the route which starts at the first
5003 * nexthop. Since sibling routes are always added at the end of
5004 * the list, find the first sibling of the last route appended
5005 */
5006 if ((nlflags & NLM_F_APPEND) && rt_last && rt_last->fib6_nsiblings) {
5007 rt = list_first_entry(&rt_last->fib6_siblings,
5008 struct fib6_info,
5009 fib6_siblings);
5010 }
5011
5012 if (rt)
5013 inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
5014 }
5015
5016 static int ip6_route_multipath_add(struct fib6_config *cfg,
5017 struct netlink_ext_ack *extack)
5018 {
5019 struct fib6_info *rt_notif = NULL, *rt_last = NULL;
5020 struct nl_info *info = &cfg->fc_nlinfo;
5021 enum fib_event_type event_type;
5022 struct fib6_config r_cfg;
5023 struct rtnexthop *rtnh;
5024 struct fib6_info *rt;
5025 struct rt6_nh *err_nh;
5026 struct rt6_nh *nh, *nh_safe;
5027 __u16 nlflags;
5028 int remaining;
5029 int attrlen;
5030 int err = 1;
5031 int nhn = 0;
5032 int replace = (cfg->fc_nlinfo.nlh &&
5033 (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
5034 LIST_HEAD(rt6_nh_list);
5035
5036 nlflags = replace ? NLM_F_REPLACE : NLM_F_CREATE;
5037 if (info->nlh && info->nlh->nlmsg_flags & NLM_F_APPEND)
5038 nlflags |= NLM_F_APPEND;
5039
5040 remaining = cfg->fc_mp_len;
5041 rtnh = (struct rtnexthop *)cfg->fc_mp;
5042
5043 /* Parse a Multipath Entry and build a list (rt6_nh_list) of
5044 * fib6_info structs per nexthop
5045 */
5046 while (rtnh_ok(rtnh, remaining)) {
5047 memcpy(&r_cfg, cfg, sizeof(*cfg));
5048 if (rtnh->rtnh_ifindex)
5049 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
5050
5051 attrlen = rtnh_attrlen(rtnh);
5052 if (attrlen > 0) {
5053 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
5054
5055 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
5056 if (nla) {
5057 r_cfg.fc_gateway = nla_get_in6_addr(nla);
5058 r_cfg.fc_flags |= RTF_GATEWAY;
5059 }
5060 r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
5061 nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
5062 if (nla)
5063 r_cfg.fc_encap_type = nla_get_u16(nla);
5064 }
5065
5066 r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
5067 rt = ip6_route_info_create(&r_cfg, GFP_KERNEL, extack);
5068 if (IS_ERR(rt)) {
5069 err = PTR_ERR(rt);
5070 rt = NULL;
5071 goto cleanup;
5072 }
5073 if (!rt6_qualify_for_ecmp(rt)) {
5074 err = -EINVAL;
5075 NL_SET_ERR_MSG(extack,
5076 "Device only routes can not be added for IPv6 using the multipath API.");
5077 fib6_info_release(rt);
5078 goto cleanup;
5079 }
5080
5081 rt->fib6_nh->fib_nh_weight = rtnh->rtnh_hops + 1;
5082
5083 err = ip6_route_info_append(info->nl_net, &rt6_nh_list,
5084 rt, &r_cfg);
5085 if (err) {
5086 fib6_info_release(rt);
5087 goto cleanup;
5088 }
5089
5090 rtnh = rtnh_next(rtnh, &remaining);
5091 }
5092
5093 if (list_empty(&rt6_nh_list)) {
5094 NL_SET_ERR_MSG(extack,
5095 "Invalid nexthop configuration - no valid nexthops");
5096 return -EINVAL;
5097 }
5098
5099 /* for add and replace send one notification with all nexthops.
5100 * Skip the notification in fib6_add_rt2node and send one with
5101 * the full route when done
5102 */
5103 info->skip_notify = 1;
5104
5105 /* For add and replace, send one notification with all nexthops. For
5106 * append, send one notification with all appended nexthops.
5107 */
5108 info->skip_notify_kernel = 1;
5109
5110 err_nh = NULL;
5111 list_for_each_entry(nh, &rt6_nh_list, next) {
5112 err = __ip6_ins_rt(nh->fib6_info, info, extack);
5113 fib6_info_release(nh->fib6_info);
5114
5115 if (!err) {
5116 /* save reference to last route successfully inserted */
5117 rt_last = nh->fib6_info;
5118
5119 /* save reference to first route for notification */
5120 if (!rt_notif)
5121 rt_notif = nh->fib6_info;
5122 }
5123
5124 /* nh->fib6_info is used or freed at this point, reset to NULL*/
5125 nh->fib6_info = NULL;
5126 if (err) {
5127 if (replace && nhn)
5128 NL_SET_ERR_MSG_MOD(extack,
5129 "multipath route replace failed (check consistency of installed routes)");
5130 err_nh = nh;
5131 goto add_errout;
5132 }
5133
5134 /* Because each route is added like a single route we remove
5135 * these flags after the first nexthop: if there is a collision,
5136 * we have already failed to add the first nexthop:
5137 * fib6_add_rt2node() has rejected it; when replacing, old
5138 * nexthops have been replaced by first new, the rest should
5139 * be added to it.
5140 */
5141 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
5142 NLM_F_REPLACE);
5143 nhn++;
5144 }
5145
5146 event_type = replace ? FIB_EVENT_ENTRY_REPLACE : FIB_EVENT_ENTRY_ADD;
5147 err = call_fib6_multipath_entry_notifiers(info->nl_net, event_type,
5148 rt_notif, nhn - 1, extack);
5149 if (err) {
5150 /* Delete all the siblings that were just added */
5151 err_nh = NULL;
5152 goto add_errout;
5153 }
5154
5155 /* success ... tell user about new route */
5156 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
5157 goto cleanup;
5158
5159 add_errout:
5160 /* send notification for routes that were added so that
5161 * the delete notifications sent by ip6_route_del are
5162 * coherent
5163 */
5164 if (rt_notif)
5165 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
5166
5167 /* Delete routes that were already added */
5168 list_for_each_entry(nh, &rt6_nh_list, next) {
5169 if (err_nh == nh)
5170 break;
5171 ip6_route_del(&nh->r_cfg, extack);
5172 }
5173
5174 cleanup:
5175 list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
5176 if (nh->fib6_info)
5177 fib6_info_release(nh->fib6_info);
5178 list_del(&nh->next);
5179 kfree(nh);
5180 }
5181
5182 return err;
5183 }
5184
5185 static int ip6_route_multipath_del(struct fib6_config *cfg,
5186 struct netlink_ext_ack *extack)
5187 {
5188 struct fib6_config r_cfg;
5189 struct rtnexthop *rtnh;
5190 int remaining;
5191 int attrlen;
5192 int err = 1, last_err = 0;
5193
5194 remaining = cfg->fc_mp_len;
5195 rtnh = (struct rtnexthop *)cfg->fc_mp;
5196
5197 /* Parse a Multipath Entry */
5198 while (rtnh_ok(rtnh, remaining)) {
5199 memcpy(&r_cfg, cfg, sizeof(*cfg));
5200 if (rtnh->rtnh_ifindex)
5201 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
5202
5203 attrlen = rtnh_attrlen(rtnh);
5204 if (attrlen > 0) {
5205 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
5206
5207 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
5208 if (nla) {
5209 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
5210 r_cfg.fc_flags |= RTF_GATEWAY;
5211 }
5212 }
5213 err = ip6_route_del(&r_cfg, extack);
5214 if (err)
5215 last_err = err;
5216
5217 rtnh = rtnh_next(rtnh, &remaining);
5218 }
5219
5220 return last_err;
5221 }
5222
5223 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
5224 struct netlink_ext_ack *extack)
5225 {
5226 struct fib6_config cfg;
5227 int err;
5228
5229 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
5230 if (err < 0)
5231 return err;
5232
5233 if (cfg.fc_nh_id &&
5234 !nexthop_find_by_id(sock_net(skb->sk), cfg.fc_nh_id)) {
5235 NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
5236 return -EINVAL;
5237 }
5238
5239 if (cfg.fc_mp)
5240 return ip6_route_multipath_del(&cfg, extack);
5241 else {
5242 cfg.fc_delete_all_nh = 1;
5243 return ip6_route_del(&cfg, extack);
5244 }
5245 }
5246
5247 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
5248 struct netlink_ext_ack *extack)
5249 {
5250 struct fib6_config cfg;
5251 int err;
5252
5253 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
5254 if (err < 0)
5255 return err;
5256
5257 if (cfg.fc_metric == 0)
5258 cfg.fc_metric = IP6_RT_PRIO_USER;
5259
5260 if (cfg.fc_mp)
5261 return ip6_route_multipath_add(&cfg, extack);
5262 else
5263 return ip6_route_add(&cfg, GFP_KERNEL, extack);
5264 }
5265
5266 /* add the overhead of this fib6_nh to nexthop_len */
5267 static int rt6_nh_nlmsg_size(struct fib6_nh *nh, void *arg)
5268 {
5269 int *nexthop_len = arg;
5270
5271 *nexthop_len += nla_total_size(0) /* RTA_MULTIPATH */
5272 + NLA_ALIGN(sizeof(struct rtnexthop))
5273 + nla_total_size(16); /* RTA_GATEWAY */
5274
5275 if (nh->fib_nh_lws) {
5276 /* RTA_ENCAP_TYPE */
5277 *nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
5278 /* RTA_ENCAP */
5279 *nexthop_len += nla_total_size(2);
5280 }
5281
5282 return 0;
5283 }
5284
5285 static size_t rt6_nlmsg_size(struct fib6_info *f6i)
5286 {
5287 int nexthop_len;
5288
5289 if (f6i->nh) {
5290 nexthop_len = nla_total_size(4); /* RTA_NH_ID */
5291 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_nlmsg_size,
5292 &nexthop_len);
5293 } else {
5294 struct fib6_nh *nh = f6i->fib6_nh;
5295
5296 nexthop_len = 0;
5297 if (f6i->fib6_nsiblings) {
5298 nexthop_len = nla_total_size(0) /* RTA_MULTIPATH */
5299 + NLA_ALIGN(sizeof(struct rtnexthop))
5300 + nla_total_size(16) /* RTA_GATEWAY */
5301 + lwtunnel_get_encap_size(nh->fib_nh_lws);
5302
5303 nexthop_len *= f6i->fib6_nsiblings;
5304 }
5305 nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
5306 }
5307
5308 return NLMSG_ALIGN(sizeof(struct rtmsg))
5309 + nla_total_size(16) /* RTA_SRC */
5310 + nla_total_size(16) /* RTA_DST */
5311 + nla_total_size(16) /* RTA_GATEWAY */
5312 + nla_total_size(16) /* RTA_PREFSRC */
5313 + nla_total_size(4) /* RTA_TABLE */
5314 + nla_total_size(4) /* RTA_IIF */
5315 + nla_total_size(4) /* RTA_OIF */
5316 + nla_total_size(4) /* RTA_PRIORITY */
5317 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
5318 + nla_total_size(sizeof(struct rta_cacheinfo))
5319 + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
5320 + nla_total_size(1) /* RTA_PREF */
5321 + nexthop_len;
5322 }
5323
5324 static int rt6_fill_node_nexthop(struct sk_buff *skb, struct nexthop *nh,
5325 unsigned char *flags)
5326 {
5327 if (nexthop_is_multipath(nh)) {
5328 struct nlattr *mp;
5329
5330 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
5331 if (!mp)
5332 goto nla_put_failure;
5333
5334 if (nexthop_mpath_fill_node(skb, nh, AF_INET6))
5335 goto nla_put_failure;
5336
5337 nla_nest_end(skb, mp);
5338 } else {
5339 struct fib6_nh *fib6_nh;
5340
5341 fib6_nh = nexthop_fib6_nh(nh);
5342 if (fib_nexthop_info(skb, &fib6_nh->nh_common, AF_INET6,
5343 flags, false) < 0)
5344 goto nla_put_failure;
5345 }
5346
5347 return 0;
5348
5349 nla_put_failure:
5350 return -EMSGSIZE;
5351 }
5352
5353 static int rt6_fill_node(struct net *net, struct sk_buff *skb,
5354 struct fib6_info *rt, struct dst_entry *dst,
5355 struct in6_addr *dest, struct in6_addr *src,
5356 int iif, int type, u32 portid, u32 seq,
5357 unsigned int flags)
5358 {
5359 struct rt6_info *rt6 = (struct rt6_info *)dst;
5360 struct rt6key *rt6_dst, *rt6_src;
5361 u32 *pmetrics, table, rt6_flags;
5362 unsigned char nh_flags = 0;
5363 struct nlmsghdr *nlh;
5364 struct rtmsg *rtm;
5365 long expires = 0;
5366
5367 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
5368 if (!nlh)
5369 return -EMSGSIZE;
5370
5371 if (rt6) {
5372 rt6_dst = &rt6->rt6i_dst;
5373 rt6_src = &rt6->rt6i_src;
5374 rt6_flags = rt6->rt6i_flags;
5375 } else {
5376 rt6_dst = &rt->fib6_dst;
5377 rt6_src = &rt->fib6_src;
5378 rt6_flags = rt->fib6_flags;
5379 }
5380
5381 rtm = nlmsg_data(nlh);
5382 rtm->rtm_family = AF_INET6;
5383 rtm->rtm_dst_len = rt6_dst->plen;
5384 rtm->rtm_src_len = rt6_src->plen;
5385 rtm->rtm_tos = 0;
5386 if (rt->fib6_table)
5387 table = rt->fib6_table->tb6_id;
5388 else
5389 table = RT6_TABLE_UNSPEC;
5390 rtm->rtm_table = table < 256 ? table : RT_TABLE_COMPAT;
5391 if (nla_put_u32(skb, RTA_TABLE, table))
5392 goto nla_put_failure;
5393
5394 rtm->rtm_type = rt->fib6_type;
5395 rtm->rtm_flags = 0;
5396 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
5397 rtm->rtm_protocol = rt->fib6_protocol;
5398
5399 if (rt6_flags & RTF_CACHE)
5400 rtm->rtm_flags |= RTM_F_CLONED;
5401
5402 if (dest) {
5403 if (nla_put_in6_addr(skb, RTA_DST, dest))
5404 goto nla_put_failure;
5405 rtm->rtm_dst_len = 128;
5406 } else if (rtm->rtm_dst_len)
5407 if (nla_put_in6_addr(skb, RTA_DST, &rt6_dst->addr))
5408 goto nla_put_failure;
5409 #ifdef CONFIG_IPV6_SUBTREES
5410 if (src) {
5411 if (nla_put_in6_addr(skb, RTA_SRC, src))
5412 goto nla_put_failure;
5413 rtm->rtm_src_len = 128;
5414 } else if (rtm->rtm_src_len &&
5415 nla_put_in6_addr(skb, RTA_SRC, &rt6_src->addr))
5416 goto nla_put_failure;
5417 #endif
5418 if (iif) {
5419 #ifdef CONFIG_IPV6_MROUTE
5420 if (ipv6_addr_is_multicast(&rt6_dst->addr)) {
5421 int err = ip6mr_get_route(net, skb, rtm, portid);
5422
5423 if (err == 0)
5424 return 0;
5425 if (err < 0)
5426 goto nla_put_failure;
5427 } else
5428 #endif
5429 if (nla_put_u32(skb, RTA_IIF, iif))
5430 goto nla_put_failure;
5431 } else if (dest) {
5432 struct in6_addr saddr_buf;
5433 if (ip6_route_get_saddr(net, rt, dest, 0, &saddr_buf) == 0 &&
5434 nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
5435 goto nla_put_failure;
5436 }
5437
5438 if (rt->fib6_prefsrc.plen) {
5439 struct in6_addr saddr_buf;
5440 saddr_buf = rt->fib6_prefsrc.addr;
5441 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
5442 goto nla_put_failure;
5443 }
5444
5445 pmetrics = dst ? dst_metrics_ptr(dst) : rt->fib6_metrics->metrics;
5446 if (rtnetlink_put_metrics(skb, pmetrics) < 0)
5447 goto nla_put_failure;
5448
5449 if (nla_put_u32(skb, RTA_PRIORITY, rt->fib6_metric))
5450 goto nla_put_failure;
5451
5452 /* For multipath routes, walk the siblings list and add
5453 * each as a nexthop within RTA_MULTIPATH.
5454 */
5455 if (rt6) {
5456 if (rt6_flags & RTF_GATEWAY &&
5457 nla_put_in6_addr(skb, RTA_GATEWAY, &rt6->rt6i_gateway))
5458 goto nla_put_failure;
5459
5460 if (dst->dev && nla_put_u32(skb, RTA_OIF, dst->dev->ifindex))
5461 goto nla_put_failure;
5462 } else if (rt->fib6_nsiblings) {
5463 struct fib6_info *sibling, *next_sibling;
5464 struct nlattr *mp;
5465
5466 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
5467 if (!mp)
5468 goto nla_put_failure;
5469
5470 if (fib_add_nexthop(skb, &rt->fib6_nh->nh_common,
5471 rt->fib6_nh->fib_nh_weight, AF_INET6) < 0)
5472 goto nla_put_failure;
5473
5474 list_for_each_entry_safe(sibling, next_sibling,
5475 &rt->fib6_siblings, fib6_siblings) {
5476 if (fib_add_nexthop(skb, &sibling->fib6_nh->nh_common,
5477 sibling->fib6_nh->fib_nh_weight,
5478 AF_INET6) < 0)
5479 goto nla_put_failure;
5480 }
5481
5482 nla_nest_end(skb, mp);
5483 } else if (rt->nh) {
5484 if (nla_put_u32(skb, RTA_NH_ID, rt->nh->id))
5485 goto nla_put_failure;
5486
5487 if (nexthop_is_blackhole(rt->nh))
5488 rtm->rtm_type = RTN_BLACKHOLE;
5489
5490 if (rt6_fill_node_nexthop(skb, rt->nh, &nh_flags) < 0)
5491 goto nla_put_failure;
5492
5493 rtm->rtm_flags |= nh_flags;
5494 } else {
5495 if (fib_nexthop_info(skb, &rt->fib6_nh->nh_common, AF_INET6,
5496 &nh_flags, false) < 0)
5497 goto nla_put_failure;
5498
5499 rtm->rtm_flags |= nh_flags;
5500 }
5501
5502 if (rt6_flags & RTF_EXPIRES) {
5503 expires = dst ? dst->expires : rt->expires;
5504 expires -= jiffies;
5505 }
5506
5507 if (rtnl_put_cacheinfo(skb, dst, 0, expires, dst ? dst->error : 0) < 0)
5508 goto nla_put_failure;
5509
5510 if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt6_flags)))
5511 goto nla_put_failure;
5512
5513
5514 nlmsg_end(skb, nlh);
5515 return 0;
5516
5517 nla_put_failure:
5518 nlmsg_cancel(skb, nlh);
5519 return -EMSGSIZE;
5520 }
5521
5522 static int fib6_info_nh_uses_dev(struct fib6_nh *nh, void *arg)
5523 {
5524 const struct net_device *dev = arg;
5525
5526 if (nh->fib_nh_dev == dev)
5527 return 1;
5528
5529 return 0;
5530 }
5531
5532 static bool fib6_info_uses_dev(const struct fib6_info *f6i,
5533 const struct net_device *dev)
5534 {
5535 if (f6i->nh) {
5536 struct net_device *_dev = (struct net_device *)dev;
5537
5538 return !!nexthop_for_each_fib6_nh(f6i->nh,
5539 fib6_info_nh_uses_dev,
5540 _dev);
5541 }
5542
5543 if (f6i->fib6_nh->fib_nh_dev == dev)
5544 return true;
5545
5546 if (f6i->fib6_nsiblings) {
5547 struct fib6_info *sibling, *next_sibling;
5548
5549 list_for_each_entry_safe(sibling, next_sibling,
5550 &f6i->fib6_siblings, fib6_siblings) {
5551 if (sibling->fib6_nh->fib_nh_dev == dev)
5552 return true;
5553 }
5554 }
5555
5556 return false;
5557 }
5558
5559 struct fib6_nh_exception_dump_walker {
5560 struct rt6_rtnl_dump_arg *dump;
5561 struct fib6_info *rt;
5562 unsigned int flags;
5563 unsigned int skip;
5564 unsigned int count;
5565 };
5566
5567 static int rt6_nh_dump_exceptions(struct fib6_nh *nh, void *arg)
5568 {
5569 struct fib6_nh_exception_dump_walker *w = arg;
5570 struct rt6_rtnl_dump_arg *dump = w->dump;
5571 struct rt6_exception_bucket *bucket;
5572 struct rt6_exception *rt6_ex;
5573 int i, err;
5574
5575 bucket = fib6_nh_get_excptn_bucket(nh, NULL);
5576 if (!bucket)
5577 return 0;
5578
5579 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
5580 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
5581 if (w->skip) {
5582 w->skip--;
5583 continue;
5584 }
5585
5586 /* Expiration of entries doesn't bump sernum, insertion
5587 * does. Removal is triggered by insertion, so we can
5588 * rely on the fact that if entries change between two
5589 * partial dumps, this node is scanned again completely,
5590 * see rt6_insert_exception() and fib6_dump_table().
5591 *
5592 * Count expired entries we go through as handled
5593 * entries that we'll skip next time, in case of partial
5594 * node dump. Otherwise, if entries expire meanwhile,
5595 * we'll skip the wrong amount.
5596 */
5597 if (rt6_check_expired(rt6_ex->rt6i)) {
5598 w->count++;
5599 continue;
5600 }
5601
5602 err = rt6_fill_node(dump->net, dump->skb, w->rt,
5603 &rt6_ex->rt6i->dst, NULL, NULL, 0,
5604 RTM_NEWROUTE,
5605 NETLINK_CB(dump->cb->skb).portid,
5606 dump->cb->nlh->nlmsg_seq, w->flags);
5607 if (err)
5608 return err;
5609
5610 w->count++;
5611 }
5612 bucket++;
5613 }
5614
5615 return 0;
5616 }
5617
5618 /* Return -1 if done with node, number of handled routes on partial dump */
5619 int rt6_dump_route(struct fib6_info *rt, void *p_arg, unsigned int skip)
5620 {
5621 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
5622 struct fib_dump_filter *filter = &arg->filter;
5623 unsigned int flags = NLM_F_MULTI;
5624 struct net *net = arg->net;
5625 int count = 0;
5626
5627 if (rt == net->ipv6.fib6_null_entry)
5628 return -1;
5629
5630 if ((filter->flags & RTM_F_PREFIX) &&
5631 !(rt->fib6_flags & RTF_PREFIX_RT)) {
5632 /* success since this is not a prefix route */
5633 return -1;
5634 }
5635 if (filter->filter_set &&
5636 ((filter->rt_type && rt->fib6_type != filter->rt_type) ||
5637 (filter->dev && !fib6_info_uses_dev(rt, filter->dev)) ||
5638 (filter->protocol && rt->fib6_protocol != filter->protocol))) {
5639 return -1;
5640 }
5641
5642 if (filter->filter_set ||
5643 !filter->dump_routes || !filter->dump_exceptions) {
5644 flags |= NLM_F_DUMP_FILTERED;
5645 }
5646
5647 if (filter->dump_routes) {
5648 if (skip) {
5649 skip--;
5650 } else {
5651 if (rt6_fill_node(net, arg->skb, rt, NULL, NULL, NULL,
5652 0, RTM_NEWROUTE,
5653 NETLINK_CB(arg->cb->skb).portid,
5654 arg->cb->nlh->nlmsg_seq, flags)) {
5655 return 0;
5656 }
5657 count++;
5658 }
5659 }
5660
5661 if (filter->dump_exceptions) {
5662 struct fib6_nh_exception_dump_walker w = { .dump = arg,
5663 .rt = rt,
5664 .flags = flags,
5665 .skip = skip,
5666 .count = 0 };
5667 int err;
5668
5669 rcu_read_lock();
5670 if (rt->nh) {
5671 err = nexthop_for_each_fib6_nh(rt->nh,
5672 rt6_nh_dump_exceptions,
5673 &w);
5674 } else {
5675 err = rt6_nh_dump_exceptions(rt->fib6_nh, &w);
5676 }
5677 rcu_read_unlock();
5678
5679 if (err)
5680 return count += w.count;
5681 }
5682
5683 return -1;
5684 }
5685
5686 static int inet6_rtm_valid_getroute_req(struct sk_buff *skb,
5687 const struct nlmsghdr *nlh,
5688 struct nlattr **tb,
5689 struct netlink_ext_ack *extack)
5690 {
5691 struct rtmsg *rtm;
5692 int i, err;
5693
5694 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
5695 NL_SET_ERR_MSG_MOD(extack,
5696 "Invalid header for get route request");
5697 return -EINVAL;
5698 }
5699
5700 if (!netlink_strict_get_check(skb))
5701 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
5702 rtm_ipv6_policy, extack);
5703
5704 rtm = nlmsg_data(nlh);
5705 if ((rtm->rtm_src_len && rtm->rtm_src_len != 128) ||
5706 (rtm->rtm_dst_len && rtm->rtm_dst_len != 128) ||
5707 rtm->rtm_table || rtm->rtm_protocol || rtm->rtm_scope ||
5708 rtm->rtm_type) {
5709 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get route request");
5710 return -EINVAL;
5711 }
5712 if (rtm->rtm_flags & ~RTM_F_FIB_MATCH) {
5713 NL_SET_ERR_MSG_MOD(extack,
5714 "Invalid flags for get route request");
5715 return -EINVAL;
5716 }
5717
5718 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
5719 rtm_ipv6_policy, extack);
5720 if (err)
5721 return err;
5722
5723 if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
5724 (tb[RTA_DST] && !rtm->rtm_dst_len)) {
5725 NL_SET_ERR_MSG_MOD(extack, "rtm_src_len and rtm_dst_len must be 128 for IPv6");
5726 return -EINVAL;
5727 }
5728
5729 for (i = 0; i <= RTA_MAX; i++) {
5730 if (!tb[i])
5731 continue;
5732
5733 switch (i) {
5734 case RTA_SRC:
5735 case RTA_DST:
5736 case RTA_IIF:
5737 case RTA_OIF:
5738 case RTA_MARK:
5739 case RTA_UID:
5740 case RTA_SPORT:
5741 case RTA_DPORT:
5742 case RTA_IP_PROTO:
5743 break;
5744 default:
5745 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request");
5746 return -EINVAL;
5747 }
5748 }
5749
5750 return 0;
5751 }
5752
5753 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5754 struct netlink_ext_ack *extack)
5755 {
5756 struct net *net = sock_net(in_skb->sk);
5757 struct nlattr *tb[RTA_MAX+1];
5758 int err, iif = 0, oif = 0;
5759 struct fib6_info *from;
5760 struct dst_entry *dst;
5761 struct rt6_info *rt;
5762 struct sk_buff *skb;
5763 struct rtmsg *rtm;
5764 struct flowi6 fl6 = {};
5765 bool fibmatch;
5766
5767 err = inet6_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
5768 if (err < 0)
5769 goto errout;
5770
5771 err = -EINVAL;
5772 rtm = nlmsg_data(nlh);
5773 fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
5774 fibmatch = !!(rtm->rtm_flags & RTM_F_FIB_MATCH);
5775
5776 if (tb[RTA_SRC]) {
5777 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
5778 goto errout;
5779
5780 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
5781 }
5782
5783 if (tb[RTA_DST]) {
5784 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
5785 goto errout;
5786
5787 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
5788 }
5789
5790 if (tb[RTA_IIF])
5791 iif = nla_get_u32(tb[RTA_IIF]);
5792
5793 if (tb[RTA_OIF])
5794 oif = nla_get_u32(tb[RTA_OIF]);
5795
5796 if (tb[RTA_MARK])
5797 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
5798
5799 if (tb[RTA_UID])
5800 fl6.flowi6_uid = make_kuid(current_user_ns(),
5801 nla_get_u32(tb[RTA_UID]));
5802 else
5803 fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
5804
5805 if (tb[RTA_SPORT])
5806 fl6.fl6_sport = nla_get_be16(tb[RTA_SPORT]);
5807
5808 if (tb[RTA_DPORT])
5809 fl6.fl6_dport = nla_get_be16(tb[RTA_DPORT]);
5810
5811 if (tb[RTA_IP_PROTO]) {
5812 err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
5813 &fl6.flowi6_proto, AF_INET6,
5814 extack);
5815 if (err)
5816 goto errout;
5817 }
5818
5819 if (iif) {
5820 struct net_device *dev;
5821 int flags = 0;
5822
5823 rcu_read_lock();
5824
5825 dev = dev_get_by_index_rcu(net, iif);
5826 if (!dev) {
5827 rcu_read_unlock();
5828 err = -ENODEV;
5829 goto errout;
5830 }
5831
5832 fl6.flowi6_iif = iif;
5833
5834 if (!ipv6_addr_any(&fl6.saddr))
5835 flags |= RT6_LOOKUP_F_HAS_SADDR;
5836
5837 dst = ip6_route_input_lookup(net, dev, &fl6, NULL, flags);
5838
5839 rcu_read_unlock();
5840 } else {
5841 fl6.flowi6_oif = oif;
5842
5843 dst = ip6_route_output(net, NULL, &fl6);
5844 }
5845
5846
5847 rt = container_of(dst, struct rt6_info, dst);
5848 if (rt->dst.error) {
5849 err = rt->dst.error;
5850 ip6_rt_put(rt);
5851 goto errout;
5852 }
5853
5854 if (rt == net->ipv6.ip6_null_entry) {
5855 err = rt->dst.error;
5856 ip6_rt_put(rt);
5857 goto errout;
5858 }
5859
5860 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
5861 if (!skb) {
5862 ip6_rt_put(rt);
5863 err = -ENOBUFS;
5864 goto errout;
5865 }
5866
5867 skb_dst_set(skb, &rt->dst);
5868
5869 rcu_read_lock();
5870 from = rcu_dereference(rt->from);
5871 if (from) {
5872 if (fibmatch)
5873 err = rt6_fill_node(net, skb, from, NULL, NULL, NULL,
5874 iif, RTM_NEWROUTE,
5875 NETLINK_CB(in_skb).portid,
5876 nlh->nlmsg_seq, 0);
5877 else
5878 err = rt6_fill_node(net, skb, from, dst, &fl6.daddr,
5879 &fl6.saddr, iif, RTM_NEWROUTE,
5880 NETLINK_CB(in_skb).portid,
5881 nlh->nlmsg_seq, 0);
5882 } else {
5883 err = -ENETUNREACH;
5884 }
5885 rcu_read_unlock();
5886
5887 if (err < 0) {
5888 kfree_skb(skb);
5889 goto errout;
5890 }
5891
5892 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
5893 errout:
5894 return err;
5895 }
5896
5897 void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
5898 unsigned int nlm_flags)
5899 {
5900 struct sk_buff *skb;
5901 struct net *net = info->nl_net;
5902 u32 seq;
5903 int err;
5904
5905 err = -ENOBUFS;
5906 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
5907
5908 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
5909 if (!skb)
5910 goto errout;
5911
5912 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
5913 event, info->portid, seq, nlm_flags);
5914 if (err < 0) {
5915 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
5916 WARN_ON(err == -EMSGSIZE);
5917 kfree_skb(skb);
5918 goto errout;
5919 }
5920 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
5921 info->nlh, gfp_any());
5922 return;
5923 errout:
5924 if (err < 0)
5925 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
5926 }
5927
5928 void fib6_rt_update(struct net *net, struct fib6_info *rt,
5929 struct nl_info *info)
5930 {
5931 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
5932 struct sk_buff *skb;
5933 int err = -ENOBUFS;
5934
5935 /* call_fib6_entry_notifiers will be removed when in-kernel notifier
5936 * is implemented and supported for nexthop objects
5937 */
5938 call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, rt, NULL);
5939
5940 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
5941 if (!skb)
5942 goto errout;
5943
5944 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
5945 RTM_NEWROUTE, info->portid, seq, NLM_F_REPLACE);
5946 if (err < 0) {
5947 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
5948 WARN_ON(err == -EMSGSIZE);
5949 kfree_skb(skb);
5950 goto errout;
5951 }
5952 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
5953 info->nlh, gfp_any());
5954 return;
5955 errout:
5956 if (err < 0)
5957 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
5958 }
5959
5960 static int ip6_route_dev_notify(struct notifier_block *this,
5961 unsigned long event, void *ptr)
5962 {
5963 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
5964 struct net *net = dev_net(dev);
5965
5966 if (!(dev->flags & IFF_LOOPBACK))
5967 return NOTIFY_OK;
5968
5969 if (event == NETDEV_REGISTER) {
5970 net->ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = dev;
5971 net->ipv6.ip6_null_entry->dst.dev = dev;
5972 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
5973 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
5974 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
5975 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
5976 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
5977 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
5978 #endif
5979 } else if (event == NETDEV_UNREGISTER &&
5980 dev->reg_state != NETREG_UNREGISTERED) {
5981 /* NETDEV_UNREGISTER could be fired for multiple times by
5982 * netdev_wait_allrefs(). Make sure we only call this once.
5983 */
5984 in6_dev_put_clear(&net->ipv6.ip6_null_entry->rt6i_idev);
5985 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
5986 in6_dev_put_clear(&net->ipv6.ip6_prohibit_entry->rt6i_idev);
5987 in6_dev_put_clear(&net->ipv6.ip6_blk_hole_entry->rt6i_idev);
5988 #endif
5989 }
5990
5991 return NOTIFY_OK;
5992 }
5993
5994 /*
5995 * /proc
5996 */
5997
5998 #ifdef CONFIG_PROC_FS
5999 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
6000 {
6001 struct net *net = (struct net *)seq->private;
6002 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
6003 net->ipv6.rt6_stats->fib_nodes,
6004 net->ipv6.rt6_stats->fib_route_nodes,
6005 atomic_read(&net->ipv6.rt6_stats->fib_rt_alloc),
6006 net->ipv6.rt6_stats->fib_rt_entries,
6007 net->ipv6.rt6_stats->fib_rt_cache,
6008 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
6009 net->ipv6.rt6_stats->fib_discarded_routes);
6010
6011 return 0;
6012 }
6013 #endif /* CONFIG_PROC_FS */
6014
6015 #ifdef CONFIG_SYSCTL
6016
6017 static
6018 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
6019 void __user *buffer, size_t *lenp, loff_t *ppos)
6020 {
6021 struct net *net;
6022 int delay;
6023 int ret;
6024 if (!write)
6025 return -EINVAL;
6026
6027 net = (struct net *)ctl->extra1;
6028 delay = net->ipv6.sysctl.flush_delay;
6029 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6030 if (ret)
6031 return ret;
6032
6033 fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
6034 return 0;
6035 }
6036
6037 static struct ctl_table ipv6_route_table_template[] = {
6038 {
6039 .procname = "flush",
6040 .data = &init_net.ipv6.sysctl.flush_delay,
6041 .maxlen = sizeof(int),
6042 .mode = 0200,
6043 .proc_handler = ipv6_sysctl_rtcache_flush
6044 },
6045 {
6046 .procname = "gc_thresh",
6047 .data = &ip6_dst_ops_template.gc_thresh,
6048 .maxlen = sizeof(int),
6049 .mode = 0644,
6050 .proc_handler = proc_dointvec,
6051 },
6052 {
6053 .procname = "max_size",
6054 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
6055 .maxlen = sizeof(int),
6056 .mode = 0644,
6057 .proc_handler = proc_dointvec,
6058 },
6059 {
6060 .procname = "gc_min_interval",
6061 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
6062 .maxlen = sizeof(int),
6063 .mode = 0644,
6064 .proc_handler = proc_dointvec_jiffies,
6065 },
6066 {
6067 .procname = "gc_timeout",
6068 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
6069 .maxlen = sizeof(int),
6070 .mode = 0644,
6071 .proc_handler = proc_dointvec_jiffies,
6072 },
6073 {
6074 .procname = "gc_interval",
6075 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
6076 .maxlen = sizeof(int),
6077 .mode = 0644,
6078 .proc_handler = proc_dointvec_jiffies,
6079 },
6080 {
6081 .procname = "gc_elasticity",
6082 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
6083 .maxlen = sizeof(int),
6084 .mode = 0644,
6085 .proc_handler = proc_dointvec,
6086 },
6087 {
6088 .procname = "mtu_expires",
6089 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
6090 .maxlen = sizeof(int),
6091 .mode = 0644,
6092 .proc_handler = proc_dointvec_jiffies,
6093 },
6094 {
6095 .procname = "min_adv_mss",
6096 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
6097 .maxlen = sizeof(int),
6098 .mode = 0644,
6099 .proc_handler = proc_dointvec,
6100 },
6101 {
6102 .procname = "gc_min_interval_ms",
6103 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
6104 .maxlen = sizeof(int),
6105 .mode = 0644,
6106 .proc_handler = proc_dointvec_ms_jiffies,
6107 },
6108 {
6109 .procname = "skip_notify_on_dev_down",
6110 .data = &init_net.ipv6.sysctl.skip_notify_on_dev_down,
6111 .maxlen = sizeof(int),
6112 .mode = 0644,
6113 .proc_handler = proc_dointvec_minmax,
6114 .extra1 = SYSCTL_ZERO,
6115 .extra2 = SYSCTL_ONE,
6116 },
6117 { }
6118 };
6119
6120 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
6121 {
6122 struct ctl_table *table;
6123
6124 table = kmemdup(ipv6_route_table_template,
6125 sizeof(ipv6_route_table_template),
6126 GFP_KERNEL);
6127
6128 if (table) {
6129 table[0].data = &net->ipv6.sysctl.flush_delay;
6130 table[0].extra1 = net;
6131 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
6132 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
6133 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
6134 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
6135 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
6136 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
6137 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
6138 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
6139 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
6140 table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down;
6141
6142 /* Don't export sysctls to unprivileged users */
6143 if (net->user_ns != &init_user_ns)
6144 table[0].procname = NULL;
6145 }
6146
6147 return table;
6148 }
6149 #endif
6150
6151 static int __net_init ip6_route_net_init(struct net *net)
6152 {
6153 int ret = -ENOMEM;
6154
6155 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
6156 sizeof(net->ipv6.ip6_dst_ops));
6157
6158 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
6159 goto out_ip6_dst_ops;
6160
6161 net->ipv6.fib6_null_entry = fib6_info_alloc(GFP_KERNEL, true);
6162 if (!net->ipv6.fib6_null_entry)
6163 goto out_ip6_dst_entries;
6164 memcpy(net->ipv6.fib6_null_entry, &fib6_null_entry_template,
6165 sizeof(*net->ipv6.fib6_null_entry));
6166
6167 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
6168 sizeof(*net->ipv6.ip6_null_entry),
6169 GFP_KERNEL);
6170 if (!net->ipv6.ip6_null_entry)
6171 goto out_fib6_null_entry;
6172 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6173 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
6174 ip6_template_metrics, true);
6175 INIT_LIST_HEAD(&net->ipv6.ip6_null_entry->rt6i_uncached);
6176
6177 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6178 net->ipv6.fib6_has_custom_rules = false;
6179 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
6180 sizeof(*net->ipv6.ip6_prohibit_entry),
6181 GFP_KERNEL);
6182 if (!net->ipv6.ip6_prohibit_entry)
6183 goto out_ip6_null_entry;
6184 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6185 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
6186 ip6_template_metrics, true);
6187 INIT_LIST_HEAD(&net->ipv6.ip6_prohibit_entry->rt6i_uncached);
6188
6189 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
6190 sizeof(*net->ipv6.ip6_blk_hole_entry),
6191 GFP_KERNEL);
6192 if (!net->ipv6.ip6_blk_hole_entry)
6193 goto out_ip6_prohibit_entry;
6194 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6195 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
6196 ip6_template_metrics, true);
6197 INIT_LIST_HEAD(&net->ipv6.ip6_blk_hole_entry->rt6i_uncached);
6198 #endif
6199
6200 net->ipv6.sysctl.flush_delay = 0;
6201 net->ipv6.sysctl.ip6_rt_max_size = 4096;
6202 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
6203 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
6204 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
6205 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
6206 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
6207 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
6208 net->ipv6.sysctl.skip_notify_on_dev_down = 0;
6209
6210 net->ipv6.ip6_rt_gc_expire = 30*HZ;
6211
6212 ret = 0;
6213 out:
6214 return ret;
6215
6216 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6217 out_ip6_prohibit_entry:
6218 kfree(net->ipv6.ip6_prohibit_entry);
6219 out_ip6_null_entry:
6220 kfree(net->ipv6.ip6_null_entry);
6221 #endif
6222 out_fib6_null_entry:
6223 kfree(net->ipv6.fib6_null_entry);
6224 out_ip6_dst_entries:
6225 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
6226 out_ip6_dst_ops:
6227 goto out;
6228 }
6229
6230 static void __net_exit ip6_route_net_exit(struct net *net)
6231 {
6232 kfree(net->ipv6.fib6_null_entry);
6233 kfree(net->ipv6.ip6_null_entry);
6234 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6235 kfree(net->ipv6.ip6_prohibit_entry);
6236 kfree(net->ipv6.ip6_blk_hole_entry);
6237 #endif
6238 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
6239 }
6240
6241 static int __net_init ip6_route_net_init_late(struct net *net)
6242 {
6243 #ifdef CONFIG_PROC_FS
6244 proc_create_net("ipv6_route", 0, net->proc_net, &ipv6_route_seq_ops,
6245 sizeof(struct ipv6_route_iter));
6246 proc_create_net_single("rt6_stats", 0444, net->proc_net,
6247 rt6_stats_seq_show, NULL);
6248 #endif
6249 return 0;
6250 }
6251
6252 static void __net_exit ip6_route_net_exit_late(struct net *net)
6253 {
6254 #ifdef CONFIG_PROC_FS
6255 remove_proc_entry("ipv6_route", net->proc_net);
6256 remove_proc_entry("rt6_stats", net->proc_net);
6257 #endif
6258 }
6259
6260 static struct pernet_operations ip6_route_net_ops = {
6261 .init = ip6_route_net_init,
6262 .exit = ip6_route_net_exit,
6263 };
6264
6265 static int __net_init ipv6_inetpeer_init(struct net *net)
6266 {
6267 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
6268
6269 if (!bp)
6270 return -ENOMEM;
6271 inet_peer_base_init(bp);
6272 net->ipv6.peers = bp;
6273 return 0;
6274 }
6275
6276 static void __net_exit ipv6_inetpeer_exit(struct net *net)
6277 {
6278 struct inet_peer_base *bp = net->ipv6.peers;
6279
6280 net->ipv6.peers = NULL;
6281 inetpeer_invalidate_tree(bp);
6282 kfree(bp);
6283 }
6284
6285 static struct pernet_operations ipv6_inetpeer_ops = {
6286 .init = ipv6_inetpeer_init,
6287 .exit = ipv6_inetpeer_exit,
6288 };
6289
6290 static struct pernet_operations ip6_route_net_late_ops = {
6291 .init = ip6_route_net_init_late,
6292 .exit = ip6_route_net_exit_late,
6293 };
6294
6295 static struct notifier_block ip6_route_dev_notifier = {
6296 .notifier_call = ip6_route_dev_notify,
6297 .priority = ADDRCONF_NOTIFY_PRIORITY - 10,
6298 };
6299
6300 void __init ip6_route_init_special_entries(void)
6301 {
6302 /* Registering of the loopback is done before this portion of code,
6303 * the loopback reference in rt6_info will not be taken, do it
6304 * manually for init_net */
6305 init_net.ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = init_net.loopback_dev;
6306 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
6307 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6308 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6309 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
6310 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6311 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
6312 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6313 #endif
6314 }
6315
6316 int __init ip6_route_init(void)
6317 {
6318 int ret;
6319 int cpu;
6320
6321 ret = -ENOMEM;
6322 ip6_dst_ops_template.kmem_cachep =
6323 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
6324 SLAB_HWCACHE_ALIGN, NULL);
6325 if (!ip6_dst_ops_template.kmem_cachep)
6326 goto out;
6327
6328 ret = dst_entries_init(&ip6_dst_blackhole_ops);
6329 if (ret)
6330 goto out_kmem_cache;
6331
6332 ret = register_pernet_subsys(&ipv6_inetpeer_ops);
6333 if (ret)
6334 goto out_dst_entries;
6335
6336 ret = register_pernet_subsys(&ip6_route_net_ops);
6337 if (ret)
6338 goto out_register_inetpeer;
6339
6340 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
6341
6342 ret = fib6_init();
6343 if (ret)
6344 goto out_register_subsys;
6345
6346 ret = xfrm6_init();
6347 if (ret)
6348 goto out_fib6_init;
6349
6350 ret = fib6_rules_init();
6351 if (ret)
6352 goto xfrm6_init;
6353
6354 ret = register_pernet_subsys(&ip6_route_net_late_ops);
6355 if (ret)
6356 goto fib6_rules_init;
6357
6358 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWROUTE,
6359 inet6_rtm_newroute, NULL, 0);
6360 if (ret < 0)
6361 goto out_register_late_subsys;
6362
6363 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELROUTE,
6364 inet6_rtm_delroute, NULL, 0);
6365 if (ret < 0)
6366 goto out_register_late_subsys;
6367
6368 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETROUTE,
6369 inet6_rtm_getroute, NULL,
6370 RTNL_FLAG_DOIT_UNLOCKED);
6371 if (ret < 0)
6372 goto out_register_late_subsys;
6373
6374 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
6375 if (ret)
6376 goto out_register_late_subsys;
6377
6378 for_each_possible_cpu(cpu) {
6379 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
6380
6381 INIT_LIST_HEAD(&ul->head);
6382 spin_lock_init(&ul->lock);
6383 }
6384
6385 out:
6386 return ret;
6387
6388 out_register_late_subsys:
6389 rtnl_unregister_all(PF_INET6);
6390 unregister_pernet_subsys(&ip6_route_net_late_ops);
6391 fib6_rules_init:
6392 fib6_rules_cleanup();
6393 xfrm6_init:
6394 xfrm6_fini();
6395 out_fib6_init:
6396 fib6_gc_cleanup();
6397 out_register_subsys:
6398 unregister_pernet_subsys(&ip6_route_net_ops);
6399 out_register_inetpeer:
6400 unregister_pernet_subsys(&ipv6_inetpeer_ops);
6401 out_dst_entries:
6402 dst_entries_destroy(&ip6_dst_blackhole_ops);
6403 out_kmem_cache:
6404 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
6405 goto out;
6406 }
6407
6408 void ip6_route_cleanup(void)
6409 {
6410 unregister_netdevice_notifier(&ip6_route_dev_notifier);
6411 unregister_pernet_subsys(&ip6_route_net_late_ops);
6412 fib6_rules_cleanup();
6413 xfrm6_fini();
6414 fib6_gc_cleanup();
6415 unregister_pernet_subsys(&ipv6_inetpeer_ops);
6416 unregister_pernet_subsys(&ip6_route_net_ops);
6417 dst_entries_destroy(&ip6_dst_blackhole_ops);
6418 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
6419 }
Linux with added FPC-III support