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30#define pr_fmt(fmt) "ICMPv6: " fmt
31
32#include <linux/module.h>
33#include <linux/errno.h>
34#include <linux/types.h>
35#include <linux/socket.h>
36#include <linux/sockios.h>
37#include <linux/sched.h>
38#include <linux/net.h>
39#include <linux/in6.h>
40#include <linux/route.h>
41#include <linux/init.h>
42#include <linux/rcupdate.h>
43#include <linux/slab.h>
44#ifdef CONFIG_SYSCTL
45#include <linux/sysctl.h>
46#endif
47
48#include <linux/if_addr.h>
49#include <linux/if_arp.h>
50#include <linux/ipv6.h>
51#include <linux/icmpv6.h>
52#include <linux/jhash.h>
53
54#include <net/sock.h>
55#include <net/snmp.h>
56
57#include <net/ipv6.h>
58#include <net/protocol.h>
59#include <net/ndisc.h>
60#include <net/ip6_route.h>
61#include <net/addrconf.h>
62#include <net/icmp.h>
63
64#include <net/netlink.h>
65#include <linux/rtnetlink.h>
66
67#include <net/flow.h>
68#include <net/ip6_checksum.h>
69#include <net/inet_common.h>
70#include <linux/proc_fs.h>
71
72#include <linux/netfilter.h>
73#include <linux/netfilter_ipv6.h>
74
75
76#define ND_DEBUG 1
77
78#define ND_PRINTK(val, level, fmt, ...) \
79do { \
80 if (val <= ND_DEBUG) \
81 net_##level##_ratelimited(fmt, ##__VA_ARGS__); \
82} while (0)
83
84static u32 ndisc_hash(const void *pkey,
85 const struct net_device *dev,
86 __u32 *hash_rnd);
87static int ndisc_constructor(struct neighbour *neigh);
88static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
89static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
90static int pndisc_constructor(struct pneigh_entry *n);
91static void pndisc_destructor(struct pneigh_entry *n);
92static void pndisc_redo(struct sk_buff *skb);
93
94static const struct neigh_ops ndisc_generic_ops = {
95 .family = AF_INET6,
96 .solicit = ndisc_solicit,
97 .error_report = ndisc_error_report,
98 .output = neigh_resolve_output,
99 .connected_output = neigh_connected_output,
100};
101
102static const struct neigh_ops ndisc_hh_ops = {
103 .family = AF_INET6,
104 .solicit = ndisc_solicit,
105 .error_report = ndisc_error_report,
106 .output = neigh_resolve_output,
107 .connected_output = neigh_resolve_output,
108};
109
110
111static const struct neigh_ops ndisc_direct_ops = {
112 .family = AF_INET6,
113 .output = neigh_direct_output,
114 .connected_output = neigh_direct_output,
115};
116
117struct neigh_table nd_tbl = {
118 .family = AF_INET6,
119 .key_len = sizeof(struct in6_addr),
120 .hash = ndisc_hash,
121 .constructor = ndisc_constructor,
122 .pconstructor = pndisc_constructor,
123 .pdestructor = pndisc_destructor,
124 .proxy_redo = pndisc_redo,
125 .id = "ndisc_cache",
126 .parms = {
127 .tbl = &nd_tbl,
128 .base_reachable_time = ND_REACHABLE_TIME,
129 .retrans_time = ND_RETRANS_TIMER,
130 .gc_staletime = 60 * HZ,
131 .reachable_time = ND_REACHABLE_TIME,
132 .delay_probe_time = 5 * HZ,
133 .queue_len_bytes = 64*1024,
134 .ucast_probes = 3,
135 .mcast_probes = 3,
136 .anycast_delay = 1 * HZ,
137 .proxy_delay = (8 * HZ) / 10,
138 .proxy_qlen = 64,
139 },
140 .gc_interval = 30 * HZ,
141 .gc_thresh1 = 128,
142 .gc_thresh2 = 512,
143 .gc_thresh3 = 1024,
144};
145
146static void ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data)
147{
148 int pad = ndisc_addr_option_pad(skb->dev->type);
149 int data_len = skb->dev->addr_len;
150 int space = ndisc_opt_addr_space(skb->dev);
151 u8 *opt = skb_put(skb, space);
152
153 opt[0] = type;
154 opt[1] = space>>3;
155
156 memset(opt + 2, 0, pad);
157 opt += pad;
158 space -= pad;
159
160 memcpy(opt+2, data, data_len);
161 data_len += 2;
162 opt += data_len;
163 if ((space -= data_len) > 0)
164 memset(opt, 0, space);
165}
166
167static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
168 struct nd_opt_hdr *end)
169{
170 int type;
171 if (!cur || !end || cur >= end)
172 return NULL;
173 type = cur->nd_opt_type;
174 do {
175 cur = ((void *)cur) + (cur->nd_opt_len << 3);
176 } while(cur < end && cur->nd_opt_type != type);
177 return cur <= end && cur->nd_opt_type == type ? cur : NULL;
178}
179
180static inline int ndisc_is_useropt(struct nd_opt_hdr *opt)
181{
182 return opt->nd_opt_type == ND_OPT_RDNSS ||
183 opt->nd_opt_type == ND_OPT_DNSSL;
184}
185
186static struct nd_opt_hdr *ndisc_next_useropt(struct nd_opt_hdr *cur,
187 struct nd_opt_hdr *end)
188{
189 if (!cur || !end || cur >= end)
190 return NULL;
191 do {
192 cur = ((void *)cur) + (cur->nd_opt_len << 3);
193 } while(cur < end && !ndisc_is_useropt(cur));
194 return cur <= end && ndisc_is_useropt(cur) ? cur : NULL;
195}
196
197struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
198 struct ndisc_options *ndopts)
199{
200 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
201
202 if (!nd_opt || opt_len < 0 || !ndopts)
203 return NULL;
204 memset(ndopts, 0, sizeof(*ndopts));
205 while (opt_len) {
206 int l;
207 if (opt_len < sizeof(struct nd_opt_hdr))
208 return NULL;
209 l = nd_opt->nd_opt_len << 3;
210 if (opt_len < l || l == 0)
211 return NULL;
212 switch (nd_opt->nd_opt_type) {
213 case ND_OPT_SOURCE_LL_ADDR:
214 case ND_OPT_TARGET_LL_ADDR:
215 case ND_OPT_MTU:
216 case ND_OPT_REDIRECT_HDR:
217 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
218 ND_PRINTK(2, warn,
219 "%s: duplicated ND6 option found: type=%d\n",
220 __func__, nd_opt->nd_opt_type);
221 } else {
222 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
223 }
224 break;
225 case ND_OPT_PREFIX_INFO:
226 ndopts->nd_opts_pi_end = nd_opt;
227 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
228 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
229 break;
230#ifdef CONFIG_IPV6_ROUTE_INFO
231 case ND_OPT_ROUTE_INFO:
232 ndopts->nd_opts_ri_end = nd_opt;
233 if (!ndopts->nd_opts_ri)
234 ndopts->nd_opts_ri = nd_opt;
235 break;
236#endif
237 default:
238 if (ndisc_is_useropt(nd_opt)) {
239 ndopts->nd_useropts_end = nd_opt;
240 if (!ndopts->nd_useropts)
241 ndopts->nd_useropts = nd_opt;
242 } else {
243
244
245
246
247
248 ND_PRINTK(2, notice,
249 "%s: ignored unsupported option; type=%d, len=%d\n",
250 __func__,
251 nd_opt->nd_opt_type,
252 nd_opt->nd_opt_len);
253 }
254 }
255 opt_len -= l;
256 nd_opt = ((void *)nd_opt) + l;
257 }
258 return ndopts;
259}
260
261int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
262{
263 switch (dev->type) {
264 case ARPHRD_ETHER:
265 case ARPHRD_IEEE802:
266 case ARPHRD_FDDI:
267 ipv6_eth_mc_map(addr, buf);
268 return 0;
269 case ARPHRD_ARCNET:
270 ipv6_arcnet_mc_map(addr, buf);
271 return 0;
272 case ARPHRD_INFINIBAND:
273 ipv6_ib_mc_map(addr, dev->broadcast, buf);
274 return 0;
275 case ARPHRD_IPGRE:
276 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
277 default:
278 if (dir) {
279 memcpy(buf, dev->broadcast, dev->addr_len);
280 return 0;
281 }
282 }
283 return -EINVAL;
284}
285
286EXPORT_SYMBOL(ndisc_mc_map);
287
288static u32 ndisc_hash(const void *pkey,
289 const struct net_device *dev,
290 __u32 *hash_rnd)
291{
292 return ndisc_hashfn(pkey, dev, hash_rnd);
293}
294
295static int ndisc_constructor(struct neighbour *neigh)
296{
297 struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key;
298 struct net_device *dev = neigh->dev;
299 struct inet6_dev *in6_dev;
300 struct neigh_parms *parms;
301 bool is_multicast = ipv6_addr_is_multicast(addr);
302
303 in6_dev = in6_dev_get(dev);
304 if (in6_dev == NULL) {
305 return -EINVAL;
306 }
307
308 parms = in6_dev->nd_parms;
309 __neigh_parms_put(neigh->parms);
310 neigh->parms = neigh_parms_clone(parms);
311
312 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
313 if (!dev->header_ops) {
314 neigh->nud_state = NUD_NOARP;
315 neigh->ops = &ndisc_direct_ops;
316 neigh->output = neigh_direct_output;
317 } else {
318 if (is_multicast) {
319 neigh->nud_state = NUD_NOARP;
320 ndisc_mc_map(addr, neigh->ha, dev, 1);
321 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
322 neigh->nud_state = NUD_NOARP;
323 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
324 if (dev->flags&IFF_LOOPBACK)
325 neigh->type = RTN_LOCAL;
326 } else if (dev->flags&IFF_POINTOPOINT) {
327 neigh->nud_state = NUD_NOARP;
328 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
329 }
330 if (dev->header_ops->cache)
331 neigh->ops = &ndisc_hh_ops;
332 else
333 neigh->ops = &ndisc_generic_ops;
334 if (neigh->nud_state&NUD_VALID)
335 neigh->output = neigh->ops->connected_output;
336 else
337 neigh->output = neigh->ops->output;
338 }
339 in6_dev_put(in6_dev);
340 return 0;
341}
342
343static int pndisc_constructor(struct pneigh_entry *n)
344{
345 struct in6_addr *addr = (struct in6_addr*)&n->key;
346 struct in6_addr maddr;
347 struct net_device *dev = n->dev;
348
349 if (dev == NULL || __in6_dev_get(dev) == NULL)
350 return -EINVAL;
351 addrconf_addr_solict_mult(addr, &maddr);
352 ipv6_dev_mc_inc(dev, &maddr);
353 return 0;
354}
355
356static void pndisc_destructor(struct pneigh_entry *n)
357{
358 struct in6_addr *addr = (struct in6_addr*)&n->key;
359 struct in6_addr maddr;
360 struct net_device *dev = n->dev;
361
362 if (dev == NULL || __in6_dev_get(dev) == NULL)
363 return;
364 addrconf_addr_solict_mult(addr, &maddr);
365 ipv6_dev_mc_dec(dev, &maddr);
366}
367
368static struct sk_buff *ndisc_alloc_skb(struct net_device *dev,
369 int len)
370{
371 int hlen = LL_RESERVED_SPACE(dev);
372 int tlen = dev->needed_tailroom;
373 struct sock *sk = dev_net(dev)->ipv6.ndisc_sk;
374 struct sk_buff *skb;
375 int err;
376
377 skb = sock_alloc_send_skb(sk,
378 hlen + sizeof(struct ipv6hdr) + len + tlen,
379 1, &err);
380 if (!skb) {
381 ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb, err=%d\n",
382 __func__, err);
383 return NULL;
384 }
385
386 skb->protocol = htons(ETH_P_IPV6);
387 skb->dev = dev;
388
389 skb_reserve(skb, hlen + sizeof(struct ipv6hdr));
390 skb_reset_transport_header(skb);
391
392 return skb;
393}
394
395static void ip6_nd_hdr(struct sk_buff *skb,
396 const struct in6_addr *saddr,
397 const struct in6_addr *daddr,
398 int hop_limit, int len)
399{
400 struct ipv6hdr *hdr;
401
402 skb_push(skb, sizeof(*hdr));
403 skb_reset_network_header(skb);
404 hdr = ipv6_hdr(skb);
405
406 ip6_flow_hdr(hdr, 0, 0);
407
408 hdr->payload_len = htons(len);
409 hdr->nexthdr = IPPROTO_ICMPV6;
410 hdr->hop_limit = hop_limit;
411
412 hdr->saddr = *saddr;
413 hdr->daddr = *daddr;
414}
415
416static void ndisc_send_skb(struct sk_buff *skb,
417 const struct in6_addr *daddr,
418 const struct in6_addr *saddr)
419{
420 struct dst_entry *dst = skb_dst(skb);
421 struct net *net = dev_net(skb->dev);
422 struct sock *sk = net->ipv6.ndisc_sk;
423 struct inet6_dev *idev;
424 int err;
425 struct icmp6hdr *icmp6h = icmp6_hdr(skb);
426 u8 type;
427
428 type = icmp6h->icmp6_type;
429
430 if (!dst) {
431 struct sock *sk = net->ipv6.ndisc_sk;
432 struct flowi6 fl6;
433
434 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, skb->dev->ifindex);
435 dst = icmp6_dst_alloc(skb->dev, &fl6);
436 if (IS_ERR(dst)) {
437 kfree_skb(skb);
438 return;
439 }
440
441 skb_dst_set(skb, dst);
442 }
443
444 icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len,
445 IPPROTO_ICMPV6,
446 csum_partial(icmp6h,
447 skb->len, 0));
448
449 ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len);
450
451 rcu_read_lock();
452 idev = __in6_dev_get(dst->dev);
453 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
454
455 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev,
456 dst_output);
457 if (!err) {
458 ICMP6MSGOUT_INC_STATS(net, idev, type);
459 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
460 }
461
462 rcu_read_unlock();
463}
464
465static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
466 const struct in6_addr *daddr,
467 const struct in6_addr *solicited_addr,
468 bool router, bool solicited, bool override, bool inc_opt)
469{
470 struct sk_buff *skb;
471 struct in6_addr tmpaddr;
472 struct inet6_ifaddr *ifp;
473 const struct in6_addr *src_addr;
474 struct nd_msg *msg;
475 int optlen = 0;
476
477
478 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
479 if (ifp) {
480 src_addr = solicited_addr;
481 if (ifp->flags & IFA_F_OPTIMISTIC)
482 override = false;
483 inc_opt |= ifp->idev->cnf.force_tllao;
484 in6_ifa_put(ifp);
485 } else {
486 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
487 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
488 &tmpaddr))
489 return;
490 src_addr = &tmpaddr;
491 }
492
493 if (!dev->addr_len)
494 inc_opt = 0;
495 if (inc_opt)
496 optlen += ndisc_opt_addr_space(dev);
497
498 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
499 if (!skb)
500 return;
501
502 msg = (struct nd_msg *)skb_put(skb, sizeof(*msg));
503 *msg = (struct nd_msg) {
504 .icmph = {
505 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
506 .icmp6_router = router,
507 .icmp6_solicited = solicited,
508 .icmp6_override = override,
509 },
510 .target = *solicited_addr,
511 };
512
513 if (inc_opt)
514 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
515 dev->dev_addr);
516
517
518 ndisc_send_skb(skb, daddr, src_addr);
519}
520
521static void ndisc_send_unsol_na(struct net_device *dev)
522{
523 struct inet6_dev *idev;
524 struct inet6_ifaddr *ifa;
525
526 idev = in6_dev_get(dev);
527 if (!idev)
528 return;
529
530 read_lock_bh(&idev->lock);
531 list_for_each_entry(ifa, &idev->addr_list, if_list) {
532 ndisc_send_na(dev, NULL, &in6addr_linklocal_allnodes, &ifa->addr,
533 !!idev->cnf.forwarding,
534 false, true,
535 true);
536 }
537 read_unlock_bh(&idev->lock);
538
539 in6_dev_put(idev);
540}
541
542void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
543 const struct in6_addr *solicit,
544 const struct in6_addr *daddr, const struct in6_addr *saddr)
545{
546 struct sk_buff *skb;
547 struct in6_addr addr_buf;
548 int inc_opt = dev->addr_len;
549 int optlen = 0;
550 struct nd_msg *msg;
551
552 if (saddr == NULL) {
553 if (ipv6_get_lladdr(dev, &addr_buf,
554 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
555 return;
556 saddr = &addr_buf;
557 }
558
559 if (ipv6_addr_any(saddr))
560 inc_opt = false;
561 if (inc_opt)
562 optlen += ndisc_opt_addr_space(dev);
563
564 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
565 if (!skb)
566 return;
567
568 msg = (struct nd_msg *)skb_put(skb, sizeof(*msg));
569 *msg = (struct nd_msg) {
570 .icmph = {
571 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
572 },
573 .target = *solicit,
574 };
575
576 if (inc_opt)
577 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
578 dev->dev_addr);
579
580 ndisc_send_skb(skb, daddr, saddr);
581}
582
583void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
584 const struct in6_addr *daddr)
585{
586 struct sk_buff *skb;
587 struct rs_msg *msg;
588 int send_sllao = dev->addr_len;
589 int optlen = 0;
590
591#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
592
593
594
595
596
597
598
599
600 if (send_sllao) {
601 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
602 dev, 1);
603 if (ifp) {
604 if (ifp->flags & IFA_F_OPTIMISTIC) {
605 send_sllao = 0;
606 }
607 in6_ifa_put(ifp);
608 } else {
609 send_sllao = 0;
610 }
611 }
612#endif
613 if (send_sllao)
614 optlen += ndisc_opt_addr_space(dev);
615
616 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
617 if (!skb)
618 return;
619
620 msg = (struct rs_msg *)skb_put(skb, sizeof(*msg));
621 *msg = (struct rs_msg) {
622 .icmph = {
623 .icmp6_type = NDISC_ROUTER_SOLICITATION,
624 },
625 };
626
627 if (send_sllao)
628 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
629 dev->dev_addr);
630
631 ndisc_send_skb(skb, daddr, saddr);
632}
633
634
635static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
636{
637
638
639
640
641 dst_link_failure(skb);
642 kfree_skb(skb);
643}
644
645
646
647static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
648{
649 struct in6_addr *saddr = NULL;
650 struct in6_addr mcaddr;
651 struct net_device *dev = neigh->dev;
652 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
653 int probes = atomic_read(&neigh->probes);
654
655 if (skb && ipv6_chk_addr(dev_net(dev), &ipv6_hdr(skb)->saddr, dev, 1))
656 saddr = &ipv6_hdr(skb)->saddr;
657
658 if ((probes -= neigh->parms->ucast_probes) < 0) {
659 if (!(neigh->nud_state & NUD_VALID)) {
660 ND_PRINTK(1, dbg,
661 "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
662 __func__, target);
663 }
664 ndisc_send_ns(dev, neigh, target, target, saddr);
665 } else if ((probes -= neigh->parms->app_probes) < 0) {
666#ifdef CONFIG_ARPD
667 neigh_app_ns(neigh);
668#endif
669 } else {
670 addrconf_addr_solict_mult(target, &mcaddr);
671 ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
672 }
673}
674
675static int pndisc_is_router(const void *pkey,
676 struct net_device *dev)
677{
678 struct pneigh_entry *n;
679 int ret = -1;
680
681 read_lock_bh(&nd_tbl.lock);
682 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
683 if (n)
684 ret = !!(n->flags & NTF_ROUTER);
685 read_unlock_bh(&nd_tbl.lock);
686
687 return ret;
688}
689
690static void ndisc_recv_ns(struct sk_buff *skb)
691{
692 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
693 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
694 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
695 u8 *lladdr = NULL;
696 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
697 offsetof(struct nd_msg, opt));
698 struct ndisc_options ndopts;
699 struct net_device *dev = skb->dev;
700 struct inet6_ifaddr *ifp;
701 struct inet6_dev *idev = NULL;
702 struct neighbour *neigh;
703 int dad = ipv6_addr_any(saddr);
704 bool inc;
705 int is_router = -1;
706
707 if (skb->len < sizeof(struct nd_msg)) {
708 ND_PRINTK(2, warn, "NS: packet too short\n");
709 return;
710 }
711
712 if (ipv6_addr_is_multicast(&msg->target)) {
713 ND_PRINTK(2, warn, "NS: multicast target address\n");
714 return;
715 }
716
717
718
719
720
721 if (dad && !ipv6_addr_is_solict_mult(daddr)) {
722 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n");
723 return;
724 }
725
726 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
727 ND_PRINTK(2, warn, "NS: invalid ND options\n");
728 return;
729 }
730
731 if (ndopts.nd_opts_src_lladdr) {
732 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
733 if (!lladdr) {
734 ND_PRINTK(2, warn,
735 "NS: invalid link-layer address length\n");
736 return;
737 }
738
739
740
741
742
743
744 if (dad) {
745 ND_PRINTK(2, warn,
746 "NS: bad DAD packet (link-layer address option)\n");
747 return;
748 }
749 }
750
751 inc = ipv6_addr_is_multicast(daddr);
752
753 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
754 if (ifp) {
755
756 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
757 if (dad) {
758
759
760
761
762
763 addrconf_dad_failure(ifp);
764 return;
765 } else {
766
767
768
769
770
771
772 if (!(ifp->flags & IFA_F_OPTIMISTIC))
773 goto out;
774 }
775 }
776
777 idev = ifp->idev;
778 } else {
779 struct net *net = dev_net(dev);
780
781 idev = in6_dev_get(dev);
782 if (!idev) {
783
784 return;
785 }
786
787 if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
788 (idev->cnf.forwarding &&
789 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
790 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
791 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
792 skb->pkt_type != PACKET_HOST &&
793 inc &&
794 idev->nd_parms->proxy_delay != 0) {
795
796
797
798
799
800
801
802 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
803 if (n)
804 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
805 goto out;
806 }
807 } else
808 goto out;
809 }
810
811 if (is_router < 0)
812 is_router = idev->cnf.forwarding;
813
814 if (dad) {
815 ndisc_send_na(dev, NULL, &in6addr_linklocal_allnodes, &msg->target,
816 !!is_router, false, (ifp != NULL), true);
817 goto out;
818 }
819
820 if (inc)
821 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
822 else
823 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
824
825
826
827
828
829 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
830 !inc || lladdr || !dev->addr_len);
831 if (neigh)
832 neigh_update(neigh, lladdr, NUD_STALE,
833 NEIGH_UPDATE_F_WEAK_OVERRIDE|
834 NEIGH_UPDATE_F_OVERRIDE);
835 if (neigh || !dev->header_ops) {
836 ndisc_send_na(dev, neigh, saddr, &msg->target,
837 !!is_router,
838 true, (ifp != NULL && inc), inc);
839 if (neigh)
840 neigh_release(neigh);
841 }
842
843out:
844 if (ifp)
845 in6_ifa_put(ifp);
846 else
847 in6_dev_put(idev);
848}
849
850static void ndisc_recv_na(struct sk_buff *skb)
851{
852 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
853 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
854 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
855 u8 *lladdr = NULL;
856 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
857 offsetof(struct nd_msg, opt));
858 struct ndisc_options ndopts;
859 struct net_device *dev = skb->dev;
860 struct inet6_ifaddr *ifp;
861 struct neighbour *neigh;
862
863 if (skb->len < sizeof(struct nd_msg)) {
864 ND_PRINTK(2, warn, "NA: packet too short\n");
865 return;
866 }
867
868 if (ipv6_addr_is_multicast(&msg->target)) {
869 ND_PRINTK(2, warn, "NA: target address is multicast\n");
870 return;
871 }
872
873 if (ipv6_addr_is_multicast(daddr) &&
874 msg->icmph.icmp6_solicited) {
875 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n");
876 return;
877 }
878
879 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
880 ND_PRINTK(2, warn, "NS: invalid ND option\n");
881 return;
882 }
883 if (ndopts.nd_opts_tgt_lladdr) {
884 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
885 if (!lladdr) {
886 ND_PRINTK(2, warn,
887 "NA: invalid link-layer address length\n");
888 return;
889 }
890 }
891 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
892 if (ifp) {
893 if (skb->pkt_type != PACKET_LOOPBACK
894 && (ifp->flags & IFA_F_TENTATIVE)) {
895 addrconf_dad_failure(ifp);
896 return;
897 }
898
899
900
901
902
903
904
905
906
907 if (skb->pkt_type != PACKET_LOOPBACK)
908 ND_PRINTK(1, warn,
909 "NA: someone advertises our address %pI6 on %s!\n",
910 &ifp->addr, ifp->idev->dev->name);
911 in6_ifa_put(ifp);
912 return;
913 }
914 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
915
916 if (neigh) {
917 u8 old_flags = neigh->flags;
918 struct net *net = dev_net(dev);
919
920 if (neigh->nud_state & NUD_FAILED)
921 goto out;
922
923
924
925
926
927
928 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
929 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
930 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
931
932 goto out;
933 }
934
935 neigh_update(neigh, lladdr,
936 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
937 NEIGH_UPDATE_F_WEAK_OVERRIDE|
938 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
939 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
940 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
941
942 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
943
944
945
946 struct rt6_info *rt;
947 rt = rt6_get_dflt_router(saddr, dev);
948 if (rt)
949 ip6_del_rt(rt);
950 }
951
952out:
953 neigh_release(neigh);
954 }
955}
956
957static void ndisc_recv_rs(struct sk_buff *skb)
958{
959 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
960 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
961 struct neighbour *neigh;
962 struct inet6_dev *idev;
963 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
964 struct ndisc_options ndopts;
965 u8 *lladdr = NULL;
966
967 if (skb->len < sizeof(*rs_msg))
968 return;
969
970 idev = __in6_dev_get(skb->dev);
971 if (!idev) {
972 ND_PRINTK(1, err, "RS: can't find in6 device\n");
973 return;
974 }
975
976
977 if (!idev->cnf.forwarding)
978 goto out;
979
980
981
982
983
984 if (ipv6_addr_any(saddr))
985 goto out;
986
987
988 if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
989 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n");
990 goto out;
991 }
992
993 if (ndopts.nd_opts_src_lladdr) {
994 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
995 skb->dev);
996 if (!lladdr)
997 goto out;
998 }
999
1000 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1001 if (neigh) {
1002 neigh_update(neigh, lladdr, NUD_STALE,
1003 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1004 NEIGH_UPDATE_F_OVERRIDE|
1005 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1006 neigh_release(neigh);
1007 }
1008out:
1009 return;
1010}
1011
1012static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1013{
1014 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1015 struct sk_buff *skb;
1016 struct nlmsghdr *nlh;
1017 struct nduseroptmsg *ndmsg;
1018 struct net *net = dev_net(ra->dev);
1019 int err;
1020 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1021 + (opt->nd_opt_len << 3));
1022 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1023
1024 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1025 if (skb == NULL) {
1026 err = -ENOBUFS;
1027 goto errout;
1028 }
1029
1030 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1031 if (nlh == NULL) {
1032 goto nla_put_failure;
1033 }
1034
1035 ndmsg = nlmsg_data(nlh);
1036 ndmsg->nduseropt_family = AF_INET6;
1037 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1038 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1039 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1040 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1041
1042 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1043
1044 if (nla_put(skb, NDUSEROPT_SRCADDR, sizeof(struct in6_addr),
1045 &ipv6_hdr(ra)->saddr))
1046 goto nla_put_failure;
1047 nlmsg_end(skb, nlh);
1048
1049 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1050 return;
1051
1052nla_put_failure:
1053 nlmsg_free(skb);
1054 err = -EMSGSIZE;
1055errout:
1056 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1057}
1058
1059static void ndisc_router_discovery(struct sk_buff *skb)
1060{
1061 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1062 struct neighbour *neigh = NULL;
1063 struct inet6_dev *in6_dev;
1064 struct rt6_info *rt = NULL;
1065 int lifetime;
1066 struct ndisc_options ndopts;
1067 int optlen;
1068 unsigned int pref = 0;
1069
1070 __u8 * opt = (__u8 *)(ra_msg + 1);
1071
1072 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) -
1073 sizeof(struct ra_msg);
1074
1075 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1076 ND_PRINTK(2, warn, "RA: source address is not link-local\n");
1077 return;
1078 }
1079 if (optlen < 0) {
1080 ND_PRINTK(2, warn, "RA: packet too short\n");
1081 return;
1082 }
1083
1084#ifdef CONFIG_IPV6_NDISC_NODETYPE
1085 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1086 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n");
1087 return;
1088 }
1089#endif
1090
1091
1092
1093
1094
1095 in6_dev = __in6_dev_get(skb->dev);
1096 if (in6_dev == NULL) {
1097 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n",
1098 skb->dev->name);
1099 return;
1100 }
1101
1102 if (!ndisc_parse_options(opt, optlen, &ndopts)) {
1103 ND_PRINTK(2, warn, "RA: invalid ND options\n");
1104 return;
1105 }
1106
1107 if (!ipv6_accept_ra(in6_dev))
1108 goto skip_linkparms;
1109
1110#ifdef CONFIG_IPV6_NDISC_NODETYPE
1111
1112 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT)
1113 goto skip_linkparms;
1114#endif
1115
1116 if (in6_dev->if_flags & IF_RS_SENT) {
1117
1118
1119
1120
1121 in6_dev->if_flags |= IF_RA_RCVD;
1122 }
1123
1124
1125
1126
1127
1128 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1129 IF_RA_OTHERCONF)) |
1130 (ra_msg->icmph.icmp6_addrconf_managed ?
1131 IF_RA_MANAGED : 0) |
1132 (ra_msg->icmph.icmp6_addrconf_other ?
1133 IF_RA_OTHERCONF : 0);
1134
1135 if (!in6_dev->cnf.accept_ra_defrtr)
1136 goto skip_defrtr;
1137
1138 if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0))
1139 goto skip_defrtr;
1140
1141 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1142
1143#ifdef CONFIG_IPV6_ROUTER_PREF
1144 pref = ra_msg->icmph.icmp6_router_pref;
1145
1146 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1147 !in6_dev->cnf.accept_ra_rtr_pref)
1148 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1149#endif
1150
1151 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1152
1153 if (rt) {
1154 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1155 if (!neigh) {
1156 ND_PRINTK(0, err,
1157 "RA: %s got default router without neighbour\n",
1158 __func__);
1159 ip6_rt_put(rt);
1160 return;
1161 }
1162 }
1163 if (rt && lifetime == 0) {
1164 ip6_del_rt(rt);
1165 rt = NULL;
1166 }
1167
1168 if (rt == NULL && lifetime) {
1169 ND_PRINTK(3, dbg, "RA: adding default router\n");
1170
1171 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1172 if (rt == NULL) {
1173 ND_PRINTK(0, err,
1174 "RA: %s failed to add default route\n",
1175 __func__);
1176 return;
1177 }
1178
1179 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1180 if (neigh == NULL) {
1181 ND_PRINTK(0, err,
1182 "RA: %s got default router without neighbour\n",
1183 __func__);
1184 ip6_rt_put(rt);
1185 return;
1186 }
1187 neigh->flags |= NTF_ROUTER;
1188 } else if (rt) {
1189 rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1190 }
1191
1192 if (rt)
1193 rt6_set_expires(rt, jiffies + (HZ * lifetime));
1194 if (ra_msg->icmph.icmp6_hop_limit) {
1195 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1196 if (rt)
1197 dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
1198 ra_msg->icmph.icmp6_hop_limit);
1199 }
1200
1201skip_defrtr:
1202
1203
1204
1205
1206
1207 if (in6_dev->nd_parms) {
1208 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1209
1210 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1211 rtime = (rtime*HZ)/1000;
1212 if (rtime < HZ/10)
1213 rtime = HZ/10;
1214 in6_dev->nd_parms->retrans_time = rtime;
1215 in6_dev->tstamp = jiffies;
1216 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1217 }
1218
1219 rtime = ntohl(ra_msg->reachable_time);
1220 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1221 rtime = (rtime*HZ)/1000;
1222
1223 if (rtime < HZ/10)
1224 rtime = HZ/10;
1225
1226 if (rtime != in6_dev->nd_parms->base_reachable_time) {
1227 in6_dev->nd_parms->base_reachable_time = rtime;
1228 in6_dev->nd_parms->gc_staletime = 3 * rtime;
1229 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1230 in6_dev->tstamp = jiffies;
1231 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1232 }
1233 }
1234 }
1235
1236skip_linkparms:
1237
1238
1239
1240
1241
1242 if (!neigh)
1243 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1244 skb->dev, 1);
1245 if (neigh) {
1246 u8 *lladdr = NULL;
1247 if (ndopts.nd_opts_src_lladdr) {
1248 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1249 skb->dev);
1250 if (!lladdr) {
1251 ND_PRINTK(2, warn,
1252 "RA: invalid link-layer address length\n");
1253 goto out;
1254 }
1255 }
1256 neigh_update(neigh, lladdr, NUD_STALE,
1257 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1258 NEIGH_UPDATE_F_OVERRIDE|
1259 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1260 NEIGH_UPDATE_F_ISROUTER);
1261 }
1262
1263 if (!ipv6_accept_ra(in6_dev))
1264 goto out;
1265
1266#ifdef CONFIG_IPV6_ROUTE_INFO
1267 if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0))
1268 goto skip_routeinfo;
1269
1270 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1271 struct nd_opt_hdr *p;
1272 for (p = ndopts.nd_opts_ri;
1273 p;
1274 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1275 struct route_info *ri = (struct route_info *)p;
1276#ifdef CONFIG_IPV6_NDISC_NODETYPE
1277 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1278 ri->prefix_len == 0)
1279 continue;
1280#endif
1281 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1282 continue;
1283 rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3,
1284 &ipv6_hdr(skb)->saddr);
1285 }
1286 }
1287
1288skip_routeinfo:
1289#endif
1290
1291#ifdef CONFIG_IPV6_NDISC_NODETYPE
1292
1293 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT)
1294 goto out;
1295#endif
1296
1297 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1298 struct nd_opt_hdr *p;
1299 for (p = ndopts.nd_opts_pi;
1300 p;
1301 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1302 addrconf_prefix_rcv(skb->dev, (u8 *)p,
1303 (p->nd_opt_len) << 3,
1304 ndopts.nd_opts_src_lladdr != NULL);
1305 }
1306 }
1307
1308 if (ndopts.nd_opts_mtu) {
1309 __be32 n;
1310 u32 mtu;
1311
1312 memcpy(&n, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1313 mtu = ntohl(n);
1314
1315 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1316 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu);
1317 } else if (in6_dev->cnf.mtu6 != mtu) {
1318 in6_dev->cnf.mtu6 = mtu;
1319
1320 if (rt)
1321 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
1322
1323 rt6_mtu_change(skb->dev, mtu);
1324 }
1325 }
1326
1327 if (ndopts.nd_useropts) {
1328 struct nd_opt_hdr *p;
1329 for (p = ndopts.nd_useropts;
1330 p;
1331 p = ndisc_next_useropt(p, ndopts.nd_useropts_end)) {
1332 ndisc_ra_useropt(skb, p);
1333 }
1334 }
1335
1336 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1337 ND_PRINTK(2, warn, "RA: invalid RA options\n");
1338 }
1339out:
1340 ip6_rt_put(rt);
1341 if (neigh)
1342 neigh_release(neigh);
1343}
1344
1345static void ndisc_redirect_rcv(struct sk_buff *skb)
1346{
1347 u8 *hdr;
1348 struct ndisc_options ndopts;
1349 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb);
1350 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
1351 offsetof(struct rd_msg, opt));
1352
1353#ifdef CONFIG_IPV6_NDISC_NODETYPE
1354 switch (skb->ndisc_nodetype) {
1355 case NDISC_NODETYPE_HOST:
1356 case NDISC_NODETYPE_NODEFAULT:
1357 ND_PRINTK(2, warn,
1358 "Redirect: from host or unauthorized router\n");
1359 return;
1360 }
1361#endif
1362
1363 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1364 ND_PRINTK(2, warn,
1365 "Redirect: source address is not link-local\n");
1366 return;
1367 }
1368
1369 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts))
1370 return;
1371
1372 if (!ndopts.nd_opts_rh) {
1373 ip6_redirect_no_header(skb, dev_net(skb->dev), 0, 0);
1374 return;
1375 }
1376
1377 hdr = (u8 *)ndopts.nd_opts_rh;
1378 hdr += 8;
1379 if (!pskb_pull(skb, hdr - skb_transport_header(skb)))
1380 return;
1381
1382 icmpv6_notify(skb, NDISC_REDIRECT, 0, 0);
1383}
1384
1385static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb,
1386 struct sk_buff *orig_skb,
1387 int rd_len)
1388{
1389 u8 *opt = skb_put(skb, rd_len);
1390
1391 memset(opt, 0, 8);
1392 *(opt++) = ND_OPT_REDIRECT_HDR;
1393 *(opt++) = (rd_len >> 3);
1394 opt += 6;
1395
1396 memcpy(opt, ipv6_hdr(orig_skb), rd_len - 8);
1397}
1398
1399void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
1400{
1401 struct net_device *dev = skb->dev;
1402 struct net *net = dev_net(dev);
1403 struct sock *sk = net->ipv6.ndisc_sk;
1404 int optlen = 0;
1405 struct inet_peer *peer;
1406 struct sk_buff *buff;
1407 struct rd_msg *msg;
1408 struct in6_addr saddr_buf;
1409 struct rt6_info *rt;
1410 struct dst_entry *dst;
1411 struct flowi6 fl6;
1412 int rd_len;
1413 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
1414 bool ret;
1415
1416 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1417 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
1418 dev->name);
1419 return;
1420 }
1421
1422 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1423 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1424 ND_PRINTK(2, warn,
1425 "Redirect: target address is not link-local unicast\n");
1426 return;
1427 }
1428
1429 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1430 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1431
1432 dst = ip6_route_output(net, NULL, &fl6);
1433 if (dst->error) {
1434 dst_release(dst);
1435 return;
1436 }
1437 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1438 if (IS_ERR(dst))
1439 return;
1440
1441 rt = (struct rt6_info *) dst;
1442
1443 if (rt->rt6i_flags & RTF_GATEWAY) {
1444 ND_PRINTK(2, warn,
1445 "Redirect: destination is not a neighbour\n");
1446 goto release;
1447 }
1448 peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1);
1449 ret = inet_peer_xrlim_allow(peer, 1*HZ);
1450 if (peer)
1451 inet_putpeer(peer);
1452 if (!ret)
1453 goto release;
1454
1455 if (dev->addr_len) {
1456 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target);
1457 if (!neigh) {
1458 ND_PRINTK(2, warn,
1459 "Redirect: no neigh for target address\n");
1460 goto release;
1461 }
1462
1463 read_lock_bh(&neigh->lock);
1464 if (neigh->nud_state & NUD_VALID) {
1465 memcpy(ha_buf, neigh->ha, dev->addr_len);
1466 read_unlock_bh(&neigh->lock);
1467 ha = ha_buf;
1468 optlen += ndisc_opt_addr_space(dev);
1469 } else
1470 read_unlock_bh(&neigh->lock);
1471
1472 neigh_release(neigh);
1473 }
1474
1475 rd_len = min_t(unsigned int,
1476 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen,
1477 skb->len + 8);
1478 rd_len &= ~0x7;
1479 optlen += rd_len;
1480
1481 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
1482 if (!buff)
1483 goto release;
1484
1485 msg = (struct rd_msg *)skb_put(buff, sizeof(*msg));
1486 *msg = (struct rd_msg) {
1487 .icmph = {
1488 .icmp6_type = NDISC_REDIRECT,
1489 },
1490 .target = *target,
1491 .dest = ipv6_hdr(skb)->daddr,
1492 };
1493
1494
1495
1496
1497
1498 if (ha)
1499 ndisc_fill_addr_option(buff, ND_OPT_TARGET_LL_ADDR, ha);
1500
1501
1502
1503
1504
1505 if (rd_len)
1506 ndisc_fill_redirect_hdr_option(buff, skb, rd_len);
1507
1508 skb_dst_set(buff, dst);
1509 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf);
1510 return;
1511
1512release:
1513 dst_release(dst);
1514}
1515
1516static void pndisc_redo(struct sk_buff *skb)
1517{
1518 ndisc_recv_ns(skb);
1519 kfree_skb(skb);
1520}
1521
1522int ndisc_rcv(struct sk_buff *skb)
1523{
1524 struct nd_msg *msg;
1525
1526 if (skb_linearize(skb))
1527 return 0;
1528
1529 msg = (struct nd_msg *)skb_transport_header(skb);
1530
1531 __skb_push(skb, skb->data - skb_transport_header(skb));
1532
1533 if (ipv6_hdr(skb)->hop_limit != 255) {
1534 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n",
1535 ipv6_hdr(skb)->hop_limit);
1536 return 0;
1537 }
1538
1539 if (msg->icmph.icmp6_code != 0) {
1540 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n",
1541 msg->icmph.icmp6_code);
1542 return 0;
1543 }
1544
1545 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1546
1547 switch (msg->icmph.icmp6_type) {
1548 case NDISC_NEIGHBOUR_SOLICITATION:
1549 ndisc_recv_ns(skb);
1550 break;
1551
1552 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1553 ndisc_recv_na(skb);
1554 break;
1555
1556 case NDISC_ROUTER_SOLICITATION:
1557 ndisc_recv_rs(skb);
1558 break;
1559
1560 case NDISC_ROUTER_ADVERTISEMENT:
1561 ndisc_router_discovery(skb);
1562 break;
1563
1564 case NDISC_REDIRECT:
1565 ndisc_redirect_rcv(skb);
1566 break;
1567 }
1568
1569 return 0;
1570}
1571
1572static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1573{
1574 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1575 struct net *net = dev_net(dev);
1576 struct inet6_dev *idev;
1577
1578 switch (event) {
1579 case NETDEV_CHANGEADDR:
1580 neigh_changeaddr(&nd_tbl, dev);
1581 fib6_run_gc(0, net, false);
1582 idev = in6_dev_get(dev);
1583 if (!idev)
1584 break;
1585 if (idev->cnf.ndisc_notify)
1586 ndisc_send_unsol_na(dev);
1587 in6_dev_put(idev);
1588 break;
1589 case NETDEV_DOWN:
1590 neigh_ifdown(&nd_tbl, dev);
1591 fib6_run_gc(0, net, false);
1592 break;
1593 case NETDEV_NOTIFY_PEERS:
1594 ndisc_send_unsol_na(dev);
1595 break;
1596 default:
1597 break;
1598 }
1599
1600 return NOTIFY_DONE;
1601}
1602
1603static struct notifier_block ndisc_netdev_notifier = {
1604 .notifier_call = ndisc_netdev_event,
1605};
1606
1607#ifdef CONFIG_SYSCTL
1608static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1609 const char *func, const char *dev_name)
1610{
1611 static char warncomm[TASK_COMM_LEN];
1612 static int warned;
1613 if (strcmp(warncomm, current->comm) && warned < 5) {
1614 strcpy(warncomm, current->comm);
1615 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
1616 warncomm, func,
1617 dev_name, ctl->procname,
1618 dev_name, ctl->procname);
1619 warned++;
1620 }
1621}
1622
1623int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
1624{
1625 struct net_device *dev = ctl->extra1;
1626 struct inet6_dev *idev;
1627 int ret;
1628
1629 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1630 (strcmp(ctl->procname, "base_reachable_time") == 0))
1631 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1632
1633 if (strcmp(ctl->procname, "retrans_time") == 0)
1634 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1635
1636 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1637 ret = proc_dointvec_jiffies(ctl, write,
1638 buffer, lenp, ppos);
1639
1640 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1641 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1642 ret = proc_dointvec_ms_jiffies(ctl, write,
1643 buffer, lenp, ppos);
1644 else
1645 ret = -1;
1646
1647 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1648 if (ctl->data == &idev->nd_parms->base_reachable_time)
1649 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1650 idev->tstamp = jiffies;
1651 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1652 in6_dev_put(idev);
1653 }
1654 return ret;
1655}
1656
1657
1658#endif
1659
1660static int __net_init ndisc_net_init(struct net *net)
1661{
1662 struct ipv6_pinfo *np;
1663 struct sock *sk;
1664 int err;
1665
1666 err = inet_ctl_sock_create(&sk, PF_INET6,
1667 SOCK_RAW, IPPROTO_ICMPV6, net);
1668 if (err < 0) {
1669 ND_PRINTK(0, err,
1670 "NDISC: Failed to initialize the control socket (err %d)\n",
1671 err);
1672 return err;
1673 }
1674
1675 net->ipv6.ndisc_sk = sk;
1676
1677 np = inet6_sk(sk);
1678 np->hop_limit = 255;
1679
1680 np->mc_loop = 0;
1681
1682 return 0;
1683}
1684
1685static void __net_exit ndisc_net_exit(struct net *net)
1686{
1687 inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
1688}
1689
1690static struct pernet_operations ndisc_net_ops = {
1691 .init = ndisc_net_init,
1692 .exit = ndisc_net_exit,
1693};
1694
1695int __init ndisc_init(void)
1696{
1697 int err;
1698
1699 err = register_pernet_subsys(&ndisc_net_ops);
1700 if (err)
1701 return err;
1702
1703
1704
1705 neigh_table_init(&nd_tbl);
1706
1707#ifdef CONFIG_SYSCTL
1708 err = neigh_sysctl_register(NULL, &nd_tbl.parms, "ipv6",
1709 &ndisc_ifinfo_sysctl_change);
1710 if (err)
1711 goto out_unregister_pernet;
1712#endif
1713 err = register_netdevice_notifier(&ndisc_netdev_notifier);
1714 if (err)
1715 goto out_unregister_sysctl;
1716out:
1717 return err;
1718
1719out_unregister_sysctl:
1720#ifdef CONFIG_SYSCTL
1721 neigh_sysctl_unregister(&nd_tbl.parms);
1722out_unregister_pernet:
1723#endif
1724 unregister_pernet_subsys(&ndisc_net_ops);
1725 goto out;
1726}
1727
1728void ndisc_cleanup(void)
1729{
1730 unregister_netdevice_notifier(&ndisc_netdev_notifier);
1731#ifdef CONFIG_SYSCTL
1732 neigh_sysctl_unregister(&nd_tbl.parms);
1733#endif
1734 neigh_table_clear(&nd_tbl);
1735 unregister_pernet_subsys(&ndisc_net_ops);
1736}
1737
