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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / net / ipv6 / ndisc.c
blobf61a5b613b52b065d8754af8adb9948f17eafc48
1 /*
2 * Neighbour Discovery for IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Mike Shaver <shaver@ingenia.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15 /*
16 * Changes:
17 *
18 * Alexey I. Froloff : RFC6106 (DNSSL) support
19 * Pierre Ynard : export userland ND options
20 * through netlink (RDNSS support)
21 * Lars Fenneberg : fixed MTU setting on receipt
22 * of an RA.
23 * Janos Farkas : kmalloc failure checks
24 * Alexey Kuznetsov : state machine reworked
25 * and moved to net/core.
26 * Pekka Savola : RFC2461 validation
27 * YOSHIFUJI Hideaki @USAGI : Verify ND options properly
28 */
29
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_ether.h>
50 #include <linux/if_arp.h>
51 #include <linux/ipv6.h>
52 #include <linux/icmpv6.h>
53 #include <linux/jhash.h>
54
55 #include <net/sock.h>
56 #include <net/snmp.h>
57
58 #include <net/ipv6.h>
59 #include <net/protocol.h>
60 #include <net/ndisc.h>
61 #include <net/ip6_route.h>
62 #include <net/addrconf.h>
63 #include <net/icmp.h>
64
65 #include <net/netlink.h>
66 #include <linux/rtnetlink.h>
67
68 #include <net/flow.h>
69 #include <net/ip6_checksum.h>
70 #include <net/inet_common.h>
71 #include <linux/proc_fs.h>
72
73 #include <linux/netfilter.h>
74 #include <linux/netfilter_ipv6.h>
75
76 static u32 ndisc_hash(const void *pkey,
77 const struct net_device *dev,
78 __u32 *hash_rnd);
79 static bool ndisc_key_eq(const struct neighbour *neigh, const void *pkey);
80 static int ndisc_constructor(struct neighbour *neigh);
81 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
82 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
83 static int pndisc_constructor(struct pneigh_entry *n);
84 static void pndisc_destructor(struct pneigh_entry *n);
85 static void pndisc_redo(struct sk_buff *skb);
86
87 static const struct neigh_ops ndisc_generic_ops = {
88 .family = AF_INET6,
89 .solicit = ndisc_solicit,
90 .error_report = ndisc_error_report,
91 .output = neigh_resolve_output,
92 .connected_output = neigh_connected_output,
93 };
94
95 static const struct neigh_ops ndisc_hh_ops = {
96 .family = AF_INET6,
97 .solicit = ndisc_solicit,
98 .error_report = ndisc_error_report,
99 .output = neigh_resolve_output,
100 .connected_output = neigh_resolve_output,
101 };
102
103
104 static const struct neigh_ops ndisc_direct_ops = {
105 .family = AF_INET6,
106 .output = neigh_direct_output,
107 .connected_output = neigh_direct_output,
108 };
109
110 struct neigh_table nd_tbl = {
111 .family = AF_INET6,
112 .key_len = sizeof(struct in6_addr),
113 .protocol = cpu_to_be16(ETH_P_IPV6),
114 .hash = ndisc_hash,
115 .key_eq = ndisc_key_eq,
116 .constructor = ndisc_constructor,
117 .pconstructor = pndisc_constructor,
118 .pdestructor = pndisc_destructor,
119 .proxy_redo = pndisc_redo,
120 .id = "ndisc_cache",
121 .parms = {
122 .tbl = &nd_tbl,
123 .reachable_time = ND_REACHABLE_TIME,
124 .data = {
125 [NEIGH_VAR_MCAST_PROBES] = 3,
126 [NEIGH_VAR_UCAST_PROBES] = 3,
127 [NEIGH_VAR_RETRANS_TIME] = ND_RETRANS_TIMER,
128 [NEIGH_VAR_BASE_REACHABLE_TIME] = ND_REACHABLE_TIME,
129 [NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ,
130 [NEIGH_VAR_GC_STALETIME] = 60 * HZ,
131 [NEIGH_VAR_QUEUE_LEN_BYTES] = SK_WMEM_MAX,
132 [NEIGH_VAR_PROXY_QLEN] = 64,
133 [NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ,
134 [NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10,
135 },
136 },
137 .gc_interval = 30 * HZ,
138 .gc_thresh1 = 128,
139 .gc_thresh2 = 512,
140 .gc_thresh3 = 1024,
141 };
142 EXPORT_SYMBOL_GPL(nd_tbl);
143
144 void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
145 int data_len, int pad)
146 {
147 int space = __ndisc_opt_addr_space(data_len, pad);
148 u8 *opt = skb_put(skb, space);
149
150 opt[0] = type;
151 opt[1] = space>>3;
152
153 memset(opt + 2, 0, pad);
154 opt += pad;
155 space -= pad;
156
157 memcpy(opt+2, data, data_len);
158 data_len += 2;
159 opt += data_len;
160 space -= data_len;
161 if (space > 0)
162 memset(opt, 0, space);
163 }
164 EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option);
165
166 static inline void ndisc_fill_addr_option(struct sk_buff *skb, int type,
167 void *data, u8 icmp6_type)
168 {
169 __ndisc_fill_addr_option(skb, type, data, skb->dev->addr_len,
170 ndisc_addr_option_pad(skb->dev->type));
171 ndisc_ops_fill_addr_option(skb->dev, skb, icmp6_type);
172 }
173
174 static inline void ndisc_fill_redirect_addr_option(struct sk_buff *skb,
175 void *ha,
176 const u8 *ops_data)
177 {
178 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, ha, NDISC_REDIRECT);
179 ndisc_ops_fill_redirect_addr_option(skb->dev, skb, ops_data);
180 }
181
182 static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
183 struct nd_opt_hdr *end)
184 {
185 int type;
186 if (!cur || !end || cur >= end)
187 return NULL;
188 type = cur->nd_opt_type;
189 do {
190 cur = ((void *)cur) + (cur->nd_opt_len << 3);
191 } while (cur < end && cur->nd_opt_type != type);
192 return cur <= end && cur->nd_opt_type == type ? cur : NULL;
193 }
194
195 static inline int ndisc_is_useropt(const struct net_device *dev,
196 struct nd_opt_hdr *opt)
197 {
198 return opt->nd_opt_type == ND_OPT_RDNSS ||
199 opt->nd_opt_type == ND_OPT_DNSSL ||
200 ndisc_ops_is_useropt(dev, opt->nd_opt_type);
201 }
202
203 static struct nd_opt_hdr *ndisc_next_useropt(const struct net_device *dev,
204 struct nd_opt_hdr *cur,
205 struct nd_opt_hdr *end)
206 {
207 if (!cur || !end || cur >= end)
208 return NULL;
209 do {
210 cur = ((void *)cur) + (cur->nd_opt_len << 3);
211 } while (cur < end && !ndisc_is_useropt(dev, cur));
212 return cur <= end && ndisc_is_useropt(dev, cur) ? cur : NULL;
213 }
214
215 struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
216 u8 *opt, int opt_len,
217 struct ndisc_options *ndopts)
218 {
219 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
220
221 if (!nd_opt || opt_len < 0 || !ndopts)
222 return NULL;
223 memset(ndopts, 0, sizeof(*ndopts));
224 while (opt_len) {
225 int l;
226 if (opt_len < sizeof(struct nd_opt_hdr))
227 return NULL;
228 l = nd_opt->nd_opt_len << 3;
229 if (opt_len < l || l == 0)
230 return NULL;
231 if (ndisc_ops_parse_options(dev, nd_opt, ndopts))
232 goto next_opt;
233 switch (nd_opt->nd_opt_type) {
234 case ND_OPT_SOURCE_LL_ADDR:
235 case ND_OPT_TARGET_LL_ADDR:
236 case ND_OPT_MTU:
237 case ND_OPT_NONCE:
238 case ND_OPT_REDIRECT_HDR:
239 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
240 ND_PRINTK(2, warn,
241 "%s: duplicated ND6 option found: type=%d\n",
242 __func__, nd_opt->nd_opt_type);
243 } else {
244 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
245 }
246 break;
247 case ND_OPT_PREFIX_INFO:
248 ndopts->nd_opts_pi_end = nd_opt;
249 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
250 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
251 break;
252 #ifdef CONFIG_IPV6_ROUTE_INFO
253 case ND_OPT_ROUTE_INFO:
254 ndopts->nd_opts_ri_end = nd_opt;
255 if (!ndopts->nd_opts_ri)
256 ndopts->nd_opts_ri = nd_opt;
257 break;
258 #endif
259 default:
260 if (ndisc_is_useropt(dev, nd_opt)) {
261 ndopts->nd_useropts_end = nd_opt;
262 if (!ndopts->nd_useropts)
263 ndopts->nd_useropts = nd_opt;
264 } else {
265 /*
266 * Unknown options must be silently ignored,
267 * to accommodate future extension to the
268 * protocol.
269 */
270 ND_PRINTK(2, notice,
271 "%s: ignored unsupported option; type=%d, len=%d\n",
272 __func__,
273 nd_opt->nd_opt_type,
274 nd_opt->nd_opt_len);
275 }
276 }
277 next_opt:
278 opt_len -= l;
279 nd_opt = ((void *)nd_opt) + l;
280 }
281 return ndopts;
282 }
283
284 int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
285 {
286 switch (dev->type) {
287 case ARPHRD_ETHER:
288 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
289 case ARPHRD_FDDI:
290 ipv6_eth_mc_map(addr, buf);
291 return 0;
292 case ARPHRD_ARCNET:
293 ipv6_arcnet_mc_map(addr, buf);
294 return 0;
295 case ARPHRD_INFINIBAND:
296 ipv6_ib_mc_map(addr, dev->broadcast, buf);
297 return 0;
298 case ARPHRD_IPGRE:
299 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
300 default:
301 if (dir) {
302 memcpy(buf, dev->broadcast, dev->addr_len);
303 return 0;
304 }
305 }
306 return -EINVAL;
307 }
308 EXPORT_SYMBOL(ndisc_mc_map);
309
310 static u32 ndisc_hash(const void *pkey,
311 const struct net_device *dev,
312 __u32 *hash_rnd)
313 {
314 return ndisc_hashfn(pkey, dev, hash_rnd);
315 }
316
317 static bool ndisc_key_eq(const struct neighbour *n, const void *pkey)
318 {
319 return neigh_key_eq128(n, pkey);
320 }
321
322 static int ndisc_constructor(struct neighbour *neigh)
323 {
324 struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key;
325 struct net_device *dev = neigh->dev;
326 struct inet6_dev *in6_dev;
327 struct neigh_parms *parms;
328 bool is_multicast = ipv6_addr_is_multicast(addr);
329
330 in6_dev = in6_dev_get(dev);
331 if (!in6_dev) {
332 return -EINVAL;
333 }
334
335 parms = in6_dev->nd_parms;
336 __neigh_parms_put(neigh->parms);
337 neigh->parms = neigh_parms_clone(parms);
338
339 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
340 if (!dev->header_ops) {
341 neigh->nud_state = NUD_NOARP;
342 neigh->ops = &ndisc_direct_ops;
343 neigh->output = neigh_direct_output;
344 } else {
345 if (is_multicast) {
346 neigh->nud_state = NUD_NOARP;
347 ndisc_mc_map(addr, neigh->ha, dev, 1);
348 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
349 neigh->nud_state = NUD_NOARP;
350 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
351 if (dev->flags&IFF_LOOPBACK)
352 neigh->type = RTN_LOCAL;
353 } else if (dev->flags&IFF_POINTOPOINT) {
354 neigh->nud_state = NUD_NOARP;
355 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
356 }
357 if (dev->header_ops->cache)
358 neigh->ops = &ndisc_hh_ops;
359 else
360 neigh->ops = &ndisc_generic_ops;
361 if (neigh->nud_state&NUD_VALID)
362 neigh->output = neigh->ops->connected_output;
363 else
364 neigh->output = neigh->ops->output;
365 }
366 in6_dev_put(in6_dev);
367 return 0;
368 }
369
370 static int pndisc_constructor(struct pneigh_entry *n)
371 {
372 struct in6_addr *addr = (struct in6_addr *)&n->key;
373 struct in6_addr maddr;
374 struct net_device *dev = n->dev;
375
376 if (!dev || !__in6_dev_get(dev))
377 return -EINVAL;
378 addrconf_addr_solict_mult(addr, &maddr);
379 ipv6_dev_mc_inc(dev, &maddr);
380 return 0;
381 }
382
383 static void pndisc_destructor(struct pneigh_entry *n)
384 {
385 struct in6_addr *addr = (struct in6_addr *)&n->key;
386 struct in6_addr maddr;
387 struct net_device *dev = n->dev;
388
389 if (!dev || !__in6_dev_get(dev))
390 return;
391 addrconf_addr_solict_mult(addr, &maddr);
392 ipv6_dev_mc_dec(dev, &maddr);
393 }
394
395 static struct sk_buff *ndisc_alloc_skb(struct net_device *dev,
396 int len)
397 {
398 int hlen = LL_RESERVED_SPACE(dev);
399 int tlen = dev->needed_tailroom;
400 struct sock *sk = dev_net(dev)->ipv6.ndisc_sk;
401 struct sk_buff *skb;
402
403 skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC);
404 if (!skb) {
405 ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n",
406 __func__);
407 return NULL;
408 }
409
410 skb->protocol = htons(ETH_P_IPV6);
411 skb->dev = dev;
412
413 skb_reserve(skb, hlen + sizeof(struct ipv6hdr));
414 skb_reset_transport_header(skb);
415
416 /* Manually assign socket ownership as we avoid calling
417 * sock_alloc_send_pskb() to bypass wmem buffer limits
418 */
419 skb_set_owner_w(skb, sk);
420
421 return skb;
422 }
423
424 static void ip6_nd_hdr(struct sk_buff *skb,
425 const struct in6_addr *saddr,
426 const struct in6_addr *daddr,
427 int hop_limit, int len)
428 {
429 struct ipv6hdr *hdr;
430 struct inet6_dev *idev;
431 unsigned tclass;
432
433 rcu_read_lock();
434 idev = __in6_dev_get(skb->dev);
435 tclass = idev ? idev->cnf.ndisc_tclass : 0;
436 rcu_read_unlock();
437
438 skb_push(skb, sizeof(*hdr));
439 skb_reset_network_header(skb);
440 hdr = ipv6_hdr(skb);
441
442 ip6_flow_hdr(hdr, tclass, 0);
443
444 hdr->payload_len = htons(len);
445 hdr->nexthdr = IPPROTO_ICMPV6;
446 hdr->hop_limit = hop_limit;
447
448 hdr->saddr = *saddr;
449 hdr->daddr = *daddr;
450 }
451
452 static void ndisc_send_skb(struct sk_buff *skb,
453 const struct in6_addr *daddr,
454 const struct in6_addr *saddr)
455 {
456 struct dst_entry *dst = skb_dst(skb);
457 struct net *net = dev_net(skb->dev);
458 struct sock *sk = net->ipv6.ndisc_sk;
459 struct inet6_dev *idev;
460 int err;
461 struct icmp6hdr *icmp6h = icmp6_hdr(skb);
462 u8 type;
463
464 type = icmp6h->icmp6_type;
465
466 if (!dst) {
467 struct flowi6 fl6;
468 int oif = skb->dev->ifindex;
469
470 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif);
471 dst = icmp6_dst_alloc(skb->dev, &fl6);
472 if (IS_ERR(dst)) {
473 kfree_skb(skb);
474 return;
475 }
476
477 skb_dst_set(skb, dst);
478 }
479
480 icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len,
481 IPPROTO_ICMPV6,
482 csum_partial(icmp6h,
483 skb->len, 0));
484
485 ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len);
486
487 rcu_read_lock();
488 idev = __in6_dev_get(dst->dev);
489 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
490
491 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
492 net, sk, skb, NULL, dst->dev,
493 dst_output);
494 if (!err) {
495 ICMP6MSGOUT_INC_STATS(net, idev, type);
496 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
497 }
498
499 rcu_read_unlock();
500 }
501
502 void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
503 const struct in6_addr *solicited_addr,
504 bool router, bool solicited, bool override, bool inc_opt)
505 {
506 struct sk_buff *skb;
507 struct in6_addr tmpaddr;
508 struct inet6_ifaddr *ifp;
509 const struct in6_addr *src_addr;
510 struct nd_msg *msg;
511 int optlen = 0;
512
513 /* for anycast or proxy, solicited_addr != src_addr */
514 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
515 if (ifp) {
516 src_addr = solicited_addr;
517 if (ifp->flags & IFA_F_OPTIMISTIC)
518 override = false;
519 inc_opt |= ifp->idev->cnf.force_tllao;
520 in6_ifa_put(ifp);
521 } else {
522 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
523 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
524 &tmpaddr))
525 return;
526 src_addr = &tmpaddr;
527 }
528
529 if (!dev->addr_len)
530 inc_opt = 0;
531 if (inc_opt)
532 optlen += ndisc_opt_addr_space(dev,
533 NDISC_NEIGHBOUR_ADVERTISEMENT);
534
535 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
536 if (!skb)
537 return;
538
539 msg = skb_put(skb, sizeof(*msg));
540 *msg = (struct nd_msg) {
541 .icmph = {
542 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
543 .icmp6_router = router,
544 .icmp6_solicited = solicited,
545 .icmp6_override = override,
546 },
547 .target = *solicited_addr,
548 };
549
550 if (inc_opt)
551 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
552 dev->dev_addr,
553 NDISC_NEIGHBOUR_ADVERTISEMENT);
554
555 ndisc_send_skb(skb, daddr, src_addr);
556 }
557
558 static void ndisc_send_unsol_na(struct net_device *dev)
559 {
560 struct inet6_dev *idev;
561 struct inet6_ifaddr *ifa;
562
563 idev = in6_dev_get(dev);
564 if (!idev)
565 return;
566
567 read_lock_bh(&idev->lock);
568 list_for_each_entry(ifa, &idev->addr_list, if_list) {
569 /* skip tentative addresses until dad completes */
570 if (ifa->flags & IFA_F_TENTATIVE &&
571 !(ifa->flags & IFA_F_OPTIMISTIC))
572 continue;
573
574 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifa->addr,
575 /*router=*/ !!idev->cnf.forwarding,
576 /*solicited=*/ false, /*override=*/ true,
577 /*inc_opt=*/ true);
578 }
579 read_unlock_bh(&idev->lock);
580
581 in6_dev_put(idev);
582 }
583
584 void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
585 const struct in6_addr *daddr, const struct in6_addr *saddr,
586 u64 nonce)
587 {
588 struct sk_buff *skb;
589 struct in6_addr addr_buf;
590 int inc_opt = dev->addr_len;
591 int optlen = 0;
592 struct nd_msg *msg;
593
594 if (!saddr) {
595 if (ipv6_get_lladdr(dev, &addr_buf,
596 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
597 return;
598 saddr = &addr_buf;
599 }
600
601 if (ipv6_addr_any(saddr))
602 inc_opt = false;
603 if (inc_opt)
604 optlen += ndisc_opt_addr_space(dev,
605 NDISC_NEIGHBOUR_SOLICITATION);
606 if (nonce != 0)
607 optlen += 8;
608
609 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
610 if (!skb)
611 return;
612
613 msg = skb_put(skb, sizeof(*msg));
614 *msg = (struct nd_msg) {
615 .icmph = {
616 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
617 },
618 .target = *solicit,
619 };
620
621 if (inc_opt)
622 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
623 dev->dev_addr,
624 NDISC_NEIGHBOUR_SOLICITATION);
625 if (nonce != 0) {
626 u8 *opt = skb_put(skb, 8);
627
628 opt[0] = ND_OPT_NONCE;
629 opt[1] = 8 >> 3;
630 memcpy(opt + 2, &nonce, 6);
631 }
632
633 ndisc_send_skb(skb, daddr, saddr);
634 }
635
636 void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
637 const struct in6_addr *daddr)
638 {
639 struct sk_buff *skb;
640 struct rs_msg *msg;
641 int send_sllao = dev->addr_len;
642 int optlen = 0;
643
644 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
645 /*
646 * According to section 2.2 of RFC 4429, we must not
647 * send router solicitations with a sllao from
648 * optimistic addresses, but we may send the solicitation
649 * if we don't include the sllao. So here we check
650 * if our address is optimistic, and if so, we
651 * suppress the inclusion of the sllao.
652 */
653 if (send_sllao) {
654 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
655 dev, 1);
656 if (ifp) {
657 if (ifp->flags & IFA_F_OPTIMISTIC) {
658 send_sllao = 0;
659 }
660 in6_ifa_put(ifp);
661 } else {
662 send_sllao = 0;
663 }
664 }
665 #endif
666 if (send_sllao)
667 optlen += ndisc_opt_addr_space(dev, NDISC_ROUTER_SOLICITATION);
668
669 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
670 if (!skb)
671 return;
672
673 msg = skb_put(skb, sizeof(*msg));
674 *msg = (struct rs_msg) {
675 .icmph = {
676 .icmp6_type = NDISC_ROUTER_SOLICITATION,
677 },
678 };
679
680 if (send_sllao)
681 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
682 dev->dev_addr,
683 NDISC_ROUTER_SOLICITATION);
684
685 ndisc_send_skb(skb, daddr, saddr);
686 }
687
688
689 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
690 {
691 /*
692 * "The sender MUST return an ICMP
693 * destination unreachable"
694 */
695 dst_link_failure(skb);
696 kfree_skb(skb);
697 }
698
699 /* Called with locked neigh: either read or both */
700
701 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
702 {
703 struct in6_addr *saddr = NULL;
704 struct in6_addr mcaddr;
705 struct net_device *dev = neigh->dev;
706 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
707 int probes = atomic_read(&neigh->probes);
708
709 if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr,
710 dev, 1,
711 IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))
712 saddr = &ipv6_hdr(skb)->saddr;
713 probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES);
714 if (probes < 0) {
715 if (!(neigh->nud_state & NUD_VALID)) {
716 ND_PRINTK(1, dbg,
717 "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
718 __func__, target);
719 }
720 ndisc_send_ns(dev, target, target, saddr, 0);
721 } else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) {
722 neigh_app_ns(neigh);
723 } else {
724 addrconf_addr_solict_mult(target, &mcaddr);
725 ndisc_send_ns(dev, target, &mcaddr, saddr, 0);
726 }
727 }
728
729 static int pndisc_is_router(const void *pkey,
730 struct net_device *dev)
731 {
732 struct pneigh_entry *n;
733 int ret = -1;
734
735 read_lock_bh(&nd_tbl.lock);
736 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
737 if (n)
738 ret = !!(n->flags & NTF_ROUTER);
739 read_unlock_bh(&nd_tbl.lock);
740
741 return ret;
742 }
743
744 void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
745 const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
746 struct ndisc_options *ndopts)
747 {
748 neigh_update(neigh, lladdr, new, flags, 0);
749 /* report ndisc ops about neighbour update */
750 ndisc_ops_update(dev, neigh, flags, icmp6_type, ndopts);
751 }
752
753 static void ndisc_recv_ns(struct sk_buff *skb)
754 {
755 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
756 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
757 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
758 u8 *lladdr = NULL;
759 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
760 offsetof(struct nd_msg, opt));
761 struct ndisc_options ndopts;
762 struct net_device *dev = skb->dev;
763 struct inet6_ifaddr *ifp;
764 struct inet6_dev *idev = NULL;
765 struct neighbour *neigh;
766 int dad = ipv6_addr_any(saddr);
767 bool inc;
768 int is_router = -1;
769 u64 nonce = 0;
770
771 if (skb->len < sizeof(struct nd_msg)) {
772 ND_PRINTK(2, warn, "NS: packet too short\n");
773 return;
774 }
775
776 if (ipv6_addr_is_multicast(&msg->target)) {
777 ND_PRINTK(2, warn, "NS: multicast target address\n");
778 return;
779 }
780
781 /*
782 * RFC2461 7.1.1:
783 * DAD has to be destined for solicited node multicast address.
784 */
785 if (dad && !ipv6_addr_is_solict_mult(daddr)) {
786 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n");
787 return;
788 }
789
790 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) {
791 ND_PRINTK(2, warn, "NS: invalid ND options\n");
792 return;
793 }
794
795 if (ndopts.nd_opts_src_lladdr) {
796 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
797 if (!lladdr) {
798 ND_PRINTK(2, warn,
799 "NS: invalid link-layer address length\n");
800 return;
801 }
802
803 /* RFC2461 7.1.1:
804 * If the IP source address is the unspecified address,
805 * there MUST NOT be source link-layer address option
806 * in the message.
807 */
808 if (dad) {
809 ND_PRINTK(2, warn,
810 "NS: bad DAD packet (link-layer address option)\n");
811 return;
812 }
813 }
814 if (ndopts.nd_opts_nonce)
815 memcpy(&nonce, (u8 *)(ndopts.nd_opts_nonce + 1), 6);
816
817 inc = ipv6_addr_is_multicast(daddr);
818
819 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
820 if (ifp) {
821 have_ifp:
822 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
823 if (dad) {
824 if (nonce != 0 && ifp->dad_nonce == nonce) {
825 u8 *np = (u8 *)&nonce;
826 /* Matching nonce if looped back */
827 ND_PRINTK(2, notice,
828 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n",
829 ifp->idev->dev->name,
830 &ifp->addr, np);
831 goto out;
832 }
833 /*
834 * We are colliding with another node
835 * who is doing DAD
836 * so fail our DAD process
837 */
838 addrconf_dad_failure(skb, ifp);
839 return;
840 } else {
841 /*
842 * This is not a dad solicitation.
843 * If we are an optimistic node,
844 * we should respond.
845 * Otherwise, we should ignore it.
846 */
847 if (!(ifp->flags & IFA_F_OPTIMISTIC))
848 goto out;
849 }
850 }
851
852 idev = ifp->idev;
853 } else {
854 struct net *net = dev_net(dev);
855
856 /* perhaps an address on the master device */
857 if (netif_is_l3_slave(dev)) {
858 struct net_device *mdev;
859
860 mdev = netdev_master_upper_dev_get_rcu(dev);
861 if (mdev) {
862 ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1);
863 if (ifp)
864 goto have_ifp;
865 }
866 }
867
868 idev = in6_dev_get(dev);
869 if (!idev) {
870 /* XXX: count this drop? */
871 return;
872 }
873
874 if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
875 (idev->cnf.forwarding &&
876 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
877 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
878 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
879 skb->pkt_type != PACKET_HOST &&
880 inc &&
881 NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) {
882 /*
883 * for anycast or proxy,
884 * sender should delay its response
885 * by a random time between 0 and
886 * MAX_ANYCAST_DELAY_TIME seconds.
887 * (RFC2461) -- yoshfuji
888 */
889 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
890 if (n)
891 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
892 goto out;
893 }
894 } else
895 goto out;
896 }
897
898 if (is_router < 0)
899 is_router = idev->cnf.forwarding;
900
901 if (dad) {
902 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target,
903 !!is_router, false, (ifp != NULL), true);
904 goto out;
905 }
906
907 if (inc)
908 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
909 else
910 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
911
912 /*
913 * update / create cache entry
914 * for the source address
915 */
916 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
917 !inc || lladdr || !dev->addr_len);
918 if (neigh)
919 ndisc_update(dev, neigh, lladdr, NUD_STALE,
920 NEIGH_UPDATE_F_WEAK_OVERRIDE|
921 NEIGH_UPDATE_F_OVERRIDE,
922 NDISC_NEIGHBOUR_SOLICITATION, &ndopts);
923 if (neigh || !dev->header_ops) {
924 ndisc_send_na(dev, saddr, &msg->target, !!is_router,
925 true, (ifp != NULL && inc), inc);
926 if (neigh)
927 neigh_release(neigh);
928 }
929
930 out:
931 if (ifp)
932 in6_ifa_put(ifp);
933 else
934 in6_dev_put(idev);
935 }
936
937 static void ndisc_recv_na(struct sk_buff *skb)
938 {
939 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
940 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
941 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
942 u8 *lladdr = NULL;
943 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
944 offsetof(struct nd_msg, opt));
945 struct ndisc_options ndopts;
946 struct net_device *dev = skb->dev;
947 struct inet6_dev *idev = __in6_dev_get(dev);
948 struct inet6_ifaddr *ifp;
949 struct neighbour *neigh;
950
951 if (skb->len < sizeof(struct nd_msg)) {
952 ND_PRINTK(2, warn, "NA: packet too short\n");
953 return;
954 }
955
956 if (ipv6_addr_is_multicast(&msg->target)) {
957 ND_PRINTK(2, warn, "NA: target address is multicast\n");
958 return;
959 }
960
961 if (ipv6_addr_is_multicast(daddr) &&
962 msg->icmph.icmp6_solicited) {
963 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n");
964 return;
965 }
966
967 /* For some 802.11 wireless deployments (and possibly other networks),
968 * there will be a NA proxy and unsolicitd packets are attacks
969 * and thus should not be accepted.
970 */
971 if (!msg->icmph.icmp6_solicited && idev &&
972 idev->cnf.drop_unsolicited_na)
973 return;
974
975 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) {
976 ND_PRINTK(2, warn, "NS: invalid ND option\n");
977 return;
978 }
979 if (ndopts.nd_opts_tgt_lladdr) {
980 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
981 if (!lladdr) {
982 ND_PRINTK(2, warn,
983 "NA: invalid link-layer address length\n");
984 return;
985 }
986 }
987 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
988 if (ifp) {
989 if (skb->pkt_type != PACKET_LOOPBACK
990 && (ifp->flags & IFA_F_TENTATIVE)) {
991 addrconf_dad_failure(skb, ifp);
992 return;
993 }
994 /* What should we make now? The advertisement
995 is invalid, but ndisc specs say nothing
996 about it. It could be misconfiguration, or
997 an smart proxy agent tries to help us :-)
998
999 We should not print the error if NA has been
1000 received from loopback - it is just our own
1001 unsolicited advertisement.
1002 */
1003 if (skb->pkt_type != PACKET_LOOPBACK)
1004 ND_PRINTK(1, warn,
1005 "NA: %pM advertised our address %pI6c on %s!\n",
1006 eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name);
1007 in6_ifa_put(ifp);
1008 return;
1009 }
1010 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
1011
1012 if (neigh) {
1013 u8 old_flags = neigh->flags;
1014 struct net *net = dev_net(dev);
1015
1016 if (neigh->nud_state & NUD_FAILED)
1017 goto out;
1018
1019 /*
1020 * Don't update the neighbor cache entry on a proxy NA from
1021 * ourselves because either the proxied node is off link or it
1022 * has already sent a NA to us.
1023 */
1024 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
1025 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
1026 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
1027 /* XXX: idev->cnf.proxy_ndp */
1028 goto out;
1029 }
1030
1031 ndisc_update(dev, neigh, lladdr,
1032 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
1033 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1034 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
1035 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1036 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0),
1037 NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts);
1038
1039 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
1040 /*
1041 * Change: router to host
1042 */
1043 rt6_clean_tohost(dev_net(dev), saddr);
1044 }
1045
1046 out:
1047 neigh_release(neigh);
1048 }
1049 }
1050
1051 static void ndisc_recv_rs(struct sk_buff *skb)
1052 {
1053 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
1054 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
1055 struct neighbour *neigh;
1056 struct inet6_dev *idev;
1057 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
1058 struct ndisc_options ndopts;
1059 u8 *lladdr = NULL;
1060
1061 if (skb->len < sizeof(*rs_msg))
1062 return;
1063
1064 idev = __in6_dev_get(skb->dev);
1065 if (!idev) {
1066 ND_PRINTK(1, err, "RS: can't find in6 device\n");
1067 return;
1068 }
1069
1070 /* Don't accept RS if we're not in router mode */
1071 if (!idev->cnf.forwarding)
1072 goto out;
1073
1074 /*
1075 * Don't update NCE if src = ::;
1076 * this implies that the source node has no ip address assigned yet.
1077 */
1078 if (ipv6_addr_any(saddr))
1079 goto out;
1080
1081 /* Parse ND options */
1082 if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts)) {
1083 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n");
1084 goto out;
1085 }
1086
1087 if (ndopts.nd_opts_src_lladdr) {
1088 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1089 skb->dev);
1090 if (!lladdr)
1091 goto out;
1092 }
1093
1094 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1095 if (neigh) {
1096 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1097 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1098 NEIGH_UPDATE_F_OVERRIDE|
1099 NEIGH_UPDATE_F_OVERRIDE_ISROUTER,
1100 NDISC_ROUTER_SOLICITATION, &ndopts);
1101 neigh_release(neigh);
1102 }
1103 out:
1104 return;
1105 }
1106
1107 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1108 {
1109 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1110 struct sk_buff *skb;
1111 struct nlmsghdr *nlh;
1112 struct nduseroptmsg *ndmsg;
1113 struct net *net = dev_net(ra->dev);
1114 int err;
1115 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1116 + (opt->nd_opt_len << 3));
1117 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1118
1119 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1120 if (!skb) {
1121 err = -ENOBUFS;
1122 goto errout;
1123 }
1124
1125 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1126 if (!nlh) {
1127 goto nla_put_failure;
1128 }
1129
1130 ndmsg = nlmsg_data(nlh);
1131 ndmsg->nduseropt_family = AF_INET6;
1132 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1133 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1134 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1135 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1136
1137 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1138
1139 if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr))
1140 goto nla_put_failure;
1141 nlmsg_end(skb, nlh);
1142
1143 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1144 return;
1145
1146 nla_put_failure:
1147 nlmsg_free(skb);
1148 err = -EMSGSIZE;
1149 errout:
1150 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1151 }
1152
1153 static void ndisc_router_discovery(struct sk_buff *skb)
1154 {
1155 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1156 struct neighbour *neigh = NULL;
1157 struct inet6_dev *in6_dev;
1158 struct rt6_info *rt = NULL;
1159 int lifetime;
1160 struct ndisc_options ndopts;
1161 int optlen;
1162 unsigned int pref = 0;
1163 __u32 old_if_flags;
1164 bool send_ifinfo_notify = false;
1165
1166 __u8 *opt = (__u8 *)(ra_msg + 1);
1167
1168 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) -
1169 sizeof(struct ra_msg);
1170
1171 ND_PRINTK(2, info,
1172 "RA: %s, dev: %s\n",
1173 __func__, skb->dev->name);
1174 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1175 ND_PRINTK(2, warn, "RA: source address is not link-local\n");
1176 return;
1177 }
1178 if (optlen < 0) {
1179 ND_PRINTK(2, warn, "RA: packet too short\n");
1180 return;
1181 }
1182
1183 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1184 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1185 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n");
1186 return;
1187 }
1188 #endif
1189
1190 /*
1191 * set the RA_RECV flag in the interface
1192 */
1193
1194 in6_dev = __in6_dev_get(skb->dev);
1195 if (!in6_dev) {
1196 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n",
1197 skb->dev->name);
1198 return;
1199 }
1200
1201 if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) {
1202 ND_PRINTK(2, warn, "RA: invalid ND options\n");
1203 return;
1204 }
1205
1206 if (!ipv6_accept_ra(in6_dev)) {
1207 ND_PRINTK(2, info,
1208 "RA: %s, did not accept ra for dev: %s\n",
1209 __func__, skb->dev->name);
1210 goto skip_linkparms;
1211 }
1212
1213 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1214 /* skip link-specific parameters from interior routers */
1215 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1216 ND_PRINTK(2, info,
1217 "RA: %s, nodetype is NODEFAULT, dev: %s\n",
1218 __func__, skb->dev->name);
1219 goto skip_linkparms;
1220 }
1221 #endif
1222
1223 if (in6_dev->if_flags & IF_RS_SENT) {
1224 /*
1225 * flag that an RA was received after an RS was sent
1226 * out on this interface.
1227 */
1228 in6_dev->if_flags |= IF_RA_RCVD;
1229 }
1230
1231 /*
1232 * Remember the managed/otherconf flags from most recently
1233 * received RA message (RFC 2462) -- yoshfuji
1234 */
1235 old_if_flags = in6_dev->if_flags;
1236 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1237 IF_RA_OTHERCONF)) |
1238 (ra_msg->icmph.icmp6_addrconf_managed ?
1239 IF_RA_MANAGED : 0) |
1240 (ra_msg->icmph.icmp6_addrconf_other ?
1241 IF_RA_OTHERCONF : 0);
1242
1243 if (old_if_flags != in6_dev->if_flags)
1244 send_ifinfo_notify = true;
1245
1246 if (!in6_dev->cnf.accept_ra_defrtr) {
1247 ND_PRINTK(2, info,
1248 "RA: %s, defrtr is false for dev: %s\n",
1249 __func__, skb->dev->name);
1250 goto skip_defrtr;
1251 }
1252
1253 /* Do not accept RA with source-addr found on local machine unless
1254 * accept_ra_from_local is set to true.
1255 */
1256 if (!in6_dev->cnf.accept_ra_from_local &&
1257 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
1258 in6_dev->dev, 0)) {
1259 ND_PRINTK(2, info,
1260 "RA from local address detected on dev: %s: default router ignored\n",
1261 skb->dev->name);
1262 goto skip_defrtr;
1263 }
1264
1265 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1266
1267 #ifdef CONFIG_IPV6_ROUTER_PREF
1268 pref = ra_msg->icmph.icmp6_router_pref;
1269 /* 10b is handled as if it were 00b (medium) */
1270 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1271 !in6_dev->cnf.accept_ra_rtr_pref)
1272 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1273 #endif
1274
1275 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1276
1277 if (rt) {
1278 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1279 if (!neigh) {
1280 ND_PRINTK(0, err,
1281 "RA: %s got default router without neighbour\n",
1282 __func__);
1283 ip6_rt_put(rt);
1284 return;
1285 }
1286 }
1287 if (rt && lifetime == 0) {
1288 ip6_del_rt(rt);
1289 rt = NULL;
1290 }
1291
1292 ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, for dev: %s\n",
1293 rt, lifetime, skb->dev->name);
1294 if (!rt && lifetime) {
1295 ND_PRINTK(3, info, "RA: adding default router\n");
1296
1297 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1298 if (!rt) {
1299 ND_PRINTK(0, err,
1300 "RA: %s failed to add default route\n",
1301 __func__);
1302 return;
1303 }
1304
1305 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1306 if (!neigh) {
1307 ND_PRINTK(0, err,
1308 "RA: %s got default router without neighbour\n",
1309 __func__);
1310 ip6_rt_put(rt);
1311 return;
1312 }
1313 neigh->flags |= NTF_ROUTER;
1314 } else if (rt) {
1315 rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1316 }
1317
1318 if (rt)
1319 rt6_set_expires(rt, jiffies + (HZ * lifetime));
1320 if (in6_dev->cnf.accept_ra_min_hop_limit < 256 &&
1321 ra_msg->icmph.icmp6_hop_limit) {
1322 if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) {
1323 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1324 if (rt)
1325 dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
1326 ra_msg->icmph.icmp6_hop_limit);
1327 } else {
1328 ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n");
1329 }
1330 }
1331
1332 skip_defrtr:
1333
1334 /*
1335 * Update Reachable Time and Retrans Timer
1336 */
1337
1338 if (in6_dev->nd_parms) {
1339 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1340
1341 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1342 rtime = (rtime*HZ)/1000;
1343 if (rtime < HZ/10)
1344 rtime = HZ/10;
1345 NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime);
1346 in6_dev->tstamp = jiffies;
1347 send_ifinfo_notify = true;
1348 }
1349
1350 rtime = ntohl(ra_msg->reachable_time);
1351 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1352 rtime = (rtime*HZ)/1000;
1353
1354 if (rtime < HZ/10)
1355 rtime = HZ/10;
1356
1357 if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) {
1358 NEIGH_VAR_SET(in6_dev->nd_parms,
1359 BASE_REACHABLE_TIME, rtime);
1360 NEIGH_VAR_SET(in6_dev->nd_parms,
1361 GC_STALETIME, 3 * rtime);
1362 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1363 in6_dev->tstamp = jiffies;
1364 send_ifinfo_notify = true;
1365 }
1366 }
1367 }
1368
1369 /*
1370 * Send a notify if RA changed managed/otherconf flags or timer settings
1371 */
1372 if (send_ifinfo_notify)
1373 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1374
1375 skip_linkparms:
1376
1377 /*
1378 * Process options.
1379 */
1380
1381 if (!neigh)
1382 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1383 skb->dev, 1);
1384 if (neigh) {
1385 u8 *lladdr = NULL;
1386 if (ndopts.nd_opts_src_lladdr) {
1387 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1388 skb->dev);
1389 if (!lladdr) {
1390 ND_PRINTK(2, warn,
1391 "RA: invalid link-layer address length\n");
1392 goto out;
1393 }
1394 }
1395 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1396 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1397 NEIGH_UPDATE_F_OVERRIDE|
1398 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1399 NEIGH_UPDATE_F_ISROUTER,
1400 NDISC_ROUTER_ADVERTISEMENT, &ndopts);
1401 }
1402
1403 if (!ipv6_accept_ra(in6_dev)) {
1404 ND_PRINTK(2, info,
1405 "RA: %s, accept_ra is false for dev: %s\n",
1406 __func__, skb->dev->name);
1407 goto out;
1408 }
1409
1410 #ifdef CONFIG_IPV6_ROUTE_INFO
1411 if (!in6_dev->cnf.accept_ra_from_local &&
1412 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
1413 in6_dev->dev, 0)) {
1414 ND_PRINTK(2, info,
1415 "RA from local address detected on dev: %s: router info ignored.\n",
1416 skb->dev->name);
1417 goto skip_routeinfo;
1418 }
1419
1420 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1421 struct nd_opt_hdr *p;
1422 for (p = ndopts.nd_opts_ri;
1423 p;
1424 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1425 struct route_info *ri = (struct route_info *)p;
1426 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1427 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1428 ri->prefix_len == 0)
1429 continue;
1430 #endif
1431 if (ri->prefix_len == 0 &&
1432 !in6_dev->cnf.accept_ra_defrtr)
1433 continue;
1434 if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen)
1435 continue;
1436 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1437 continue;
1438 rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3,
1439 &ipv6_hdr(skb)->saddr);
1440 }
1441 }
1442
1443 skip_routeinfo:
1444 #endif
1445
1446 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1447 /* skip link-specific ndopts from interior routers */
1448 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1449 ND_PRINTK(2, info,
1450 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n",
1451 __func__, skb->dev->name);
1452 goto out;
1453 }
1454 #endif
1455
1456 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1457 struct nd_opt_hdr *p;
1458 for (p = ndopts.nd_opts_pi;
1459 p;
1460 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1461 addrconf_prefix_rcv(skb->dev, (u8 *)p,
1462 (p->nd_opt_len) << 3,
1463 ndopts.nd_opts_src_lladdr != NULL);
1464 }
1465 }
1466
1467 if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) {
1468 __be32 n;
1469 u32 mtu;
1470
1471 memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1472 mtu = ntohl(n);
1473
1474 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1475 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu);
1476 } else if (in6_dev->cnf.mtu6 != mtu) {
1477 in6_dev->cnf.mtu6 = mtu;
1478
1479 if (rt)
1480 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
1481
1482 rt6_mtu_change(skb->dev, mtu);
1483 }
1484 }
1485
1486 if (ndopts.nd_useropts) {
1487 struct nd_opt_hdr *p;
1488 for (p = ndopts.nd_useropts;
1489 p;
1490 p = ndisc_next_useropt(skb->dev, p,
1491 ndopts.nd_useropts_end)) {
1492 ndisc_ra_useropt(skb, p);
1493 }
1494 }
1495
1496 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1497 ND_PRINTK(2, warn, "RA: invalid RA options\n");
1498 }
1499 out:
1500 ip6_rt_put(rt);
1501 if (neigh)
1502 neigh_release(neigh);
1503 }
1504
1505 static void ndisc_redirect_rcv(struct sk_buff *skb)
1506 {
1507 u8 *hdr;
1508 struct ndisc_options ndopts;
1509 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb);
1510 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
1511 offsetof(struct rd_msg, opt));
1512
1513 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1514 switch (skb->ndisc_nodetype) {
1515 case NDISC_NODETYPE_HOST:
1516 case NDISC_NODETYPE_NODEFAULT:
1517 ND_PRINTK(2, warn,
1518 "Redirect: from host or unauthorized router\n");
1519 return;
1520 }
1521 #endif
1522
1523 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1524 ND_PRINTK(2, warn,
1525 "Redirect: source address is not link-local\n");
1526 return;
1527 }
1528
1529 if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts))
1530 return;
1531
1532 if (!ndopts.nd_opts_rh) {
1533 ip6_redirect_no_header(skb, dev_net(skb->dev),
1534 skb->dev->ifindex, 0);
1535 return;
1536 }
1537
1538 hdr = (u8 *)ndopts.nd_opts_rh;
1539 hdr += 8;
1540 if (!pskb_pull(skb, hdr - skb_transport_header(skb)))
1541 return;
1542
1543 icmpv6_notify(skb, NDISC_REDIRECT, 0, 0);
1544 }
1545
1546 static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb,
1547 struct sk_buff *orig_skb,
1548 int rd_len)
1549 {
1550 u8 *opt = skb_put(skb, rd_len);
1551
1552 memset(opt, 0, 8);
1553 *(opt++) = ND_OPT_REDIRECT_HDR;
1554 *(opt++) = (rd_len >> 3);
1555 opt += 6;
1556
1557 memcpy(opt, ipv6_hdr(orig_skb), rd_len - 8);
1558 }
1559
1560 void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
1561 {
1562 struct net_device *dev = skb->dev;
1563 struct net *net = dev_net(dev);
1564 struct sock *sk = net->ipv6.ndisc_sk;
1565 int optlen = 0;
1566 struct inet_peer *peer;
1567 struct sk_buff *buff;
1568 struct rd_msg *msg;
1569 struct in6_addr saddr_buf;
1570 struct rt6_info *rt;
1571 struct dst_entry *dst;
1572 struct flowi6 fl6;
1573 int rd_len;
1574 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL,
1575 ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL;
1576 bool ret;
1577
1578 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1579 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
1580 dev->name);
1581 return;
1582 }
1583
1584 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1585 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1586 ND_PRINTK(2, warn,
1587 "Redirect: target address is not link-local unicast\n");
1588 return;
1589 }
1590
1591 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1592 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1593
1594 dst = ip6_route_output(net, NULL, &fl6);
1595 if (dst->error) {
1596 dst_release(dst);
1597 return;
1598 }
1599 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1600 if (IS_ERR(dst))
1601 return;
1602
1603 rt = (struct rt6_info *) dst;
1604
1605 if (rt->rt6i_flags & RTF_GATEWAY) {
1606 ND_PRINTK(2, warn,
1607 "Redirect: destination is not a neighbour\n");
1608 goto release;
1609 }
1610 peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1);
1611 ret = inet_peer_xrlim_allow(peer, 1*HZ);
1612 if (peer)
1613 inet_putpeer(peer);
1614 if (!ret)
1615 goto release;
1616
1617 if (dev->addr_len) {
1618 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target);
1619 if (!neigh) {
1620 ND_PRINTK(2, warn,
1621 "Redirect: no neigh for target address\n");
1622 goto release;
1623 }
1624
1625 read_lock_bh(&neigh->lock);
1626 if (neigh->nud_state & NUD_VALID) {
1627 memcpy(ha_buf, neigh->ha, dev->addr_len);
1628 read_unlock_bh(&neigh->lock);
1629 ha = ha_buf;
1630 optlen += ndisc_redirect_opt_addr_space(dev, neigh,
1631 ops_data_buf,
1632 &ops_data);
1633 } else
1634 read_unlock_bh(&neigh->lock);
1635
1636 neigh_release(neigh);
1637 }
1638
1639 rd_len = min_t(unsigned int,
1640 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen,
1641 skb->len + 8);
1642 rd_len &= ~0x7;
1643 optlen += rd_len;
1644
1645 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
1646 if (!buff)
1647 goto release;
1648
1649 msg = skb_put(buff, sizeof(*msg));
1650 *msg = (struct rd_msg) {
1651 .icmph = {
1652 .icmp6_type = NDISC_REDIRECT,
1653 },
1654 .target = *target,
1655 .dest = ipv6_hdr(skb)->daddr,
1656 };
1657
1658 /*
1659 * include target_address option
1660 */
1661
1662 if (ha)
1663 ndisc_fill_redirect_addr_option(buff, ha, ops_data);
1664
1665 /*
1666 * build redirect option and copy skb over to the new packet.
1667 */
1668
1669 if (rd_len)
1670 ndisc_fill_redirect_hdr_option(buff, skb, rd_len);
1671
1672 skb_dst_set(buff, dst);
1673 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf);
1674 return;
1675
1676 release:
1677 dst_release(dst);
1678 }
1679
1680 static void pndisc_redo(struct sk_buff *skb)
1681 {
1682 ndisc_recv_ns(skb);
1683 kfree_skb(skb);
1684 }
1685
1686 static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb)
1687 {
1688 struct inet6_dev *idev = __in6_dev_get(skb->dev);
1689
1690 if (!idev)
1691 return true;
1692 if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED &&
1693 idev->cnf.suppress_frag_ndisc) {
1694 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n");
1695 return true;
1696 }
1697 return false;
1698 }
1699
1700 int ndisc_rcv(struct sk_buff *skb)
1701 {
1702 struct nd_msg *msg;
1703
1704 if (ndisc_suppress_frag_ndisc(skb))
1705 return 0;
1706
1707 if (skb_linearize(skb))
1708 return 0;
1709
1710 msg = (struct nd_msg *)skb_transport_header(skb);
1711
1712 __skb_push(skb, skb->data - skb_transport_header(skb));
1713
1714 if (ipv6_hdr(skb)->hop_limit != 255) {
1715 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n",
1716 ipv6_hdr(skb)->hop_limit);
1717 return 0;
1718 }
1719
1720 if (msg->icmph.icmp6_code != 0) {
1721 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n",
1722 msg->icmph.icmp6_code);
1723 return 0;
1724 }
1725
1726 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1727
1728 switch (msg->icmph.icmp6_type) {
1729 case NDISC_NEIGHBOUR_SOLICITATION:
1730 ndisc_recv_ns(skb);
1731 break;
1732
1733 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1734 ndisc_recv_na(skb);
1735 break;
1736
1737 case NDISC_ROUTER_SOLICITATION:
1738 ndisc_recv_rs(skb);
1739 break;
1740
1741 case NDISC_ROUTER_ADVERTISEMENT:
1742 ndisc_router_discovery(skb);
1743 break;
1744
1745 case NDISC_REDIRECT:
1746 ndisc_redirect_rcv(skb);
1747 break;
1748 }
1749
1750 return 0;
1751 }
1752
1753 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1754 {
1755 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1756 struct netdev_notifier_change_info *change_info;
1757 struct net *net = dev_net(dev);
1758 struct inet6_dev *idev;
1759
1760 switch (event) {
1761 case NETDEV_CHANGEADDR:
1762 neigh_changeaddr(&nd_tbl, dev);
1763 fib6_run_gc(0, net, false);
1764 /* fallthrough */
1765 case NETDEV_UP:
1766 idev = in6_dev_get(dev);
1767 if (!idev)
1768 break;
1769 if (idev->cnf.ndisc_notify ||
1770 net->ipv6.devconf_all->ndisc_notify)
1771 ndisc_send_unsol_na(dev);
1772 in6_dev_put(idev);
1773 break;
1774 case NETDEV_CHANGE:
1775 change_info = ptr;
1776 if (change_info->flags_changed & IFF_NOARP)
1777 neigh_changeaddr(&nd_tbl, dev);
1778 break;
1779 case NETDEV_DOWN:
1780 neigh_ifdown(&nd_tbl, dev);
1781 fib6_run_gc(0, net, false);
1782 break;
1783 case NETDEV_NOTIFY_PEERS:
1784 ndisc_send_unsol_na(dev);
1785 break;
1786 default:
1787 break;
1788 }
1789
1790 return NOTIFY_DONE;
1791 }
1792
1793 static struct notifier_block ndisc_netdev_notifier = {
1794 .notifier_call = ndisc_netdev_event,
1795 .priority = ADDRCONF_NOTIFY_PRIORITY - 5,
1796 };
1797
1798 #ifdef CONFIG_SYSCTL
1799 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1800 const char *func, const char *dev_name)
1801 {
1802 static char warncomm[TASK_COMM_LEN];
1803 static int warned;
1804 if (strcmp(warncomm, current->comm) && warned < 5) {
1805 strcpy(warncomm, current->comm);
1806 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
1807 warncomm, func,
1808 dev_name, ctl->procname,
1809 dev_name, ctl->procname);
1810 warned++;
1811 }
1812 }
1813
1814 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
1815 {
1816 struct net_device *dev = ctl->extra1;
1817 struct inet6_dev *idev;
1818 int ret;
1819
1820 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1821 (strcmp(ctl->procname, "base_reachable_time") == 0))
1822 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1823
1824 if (strcmp(ctl->procname, "retrans_time") == 0)
1825 ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos);
1826
1827 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1828 ret = neigh_proc_dointvec_jiffies(ctl, write,
1829 buffer, lenp, ppos);
1830
1831 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1832 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1833 ret = neigh_proc_dointvec_ms_jiffies(ctl, write,
1834 buffer, lenp, ppos);
1835 else
1836 ret = -1;
1837
1838 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1839 if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME))
1840 idev->nd_parms->reachable_time =
1841 neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME));
1842 idev->tstamp = jiffies;
1843 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1844 in6_dev_put(idev);
1845 }
1846 return ret;
1847 }
1848
1849
1850 #endif
1851
1852 static int __net_init ndisc_net_init(struct net *net)
1853 {
1854 struct ipv6_pinfo *np;
1855 struct sock *sk;
1856 int err;
1857
1858 err = inet_ctl_sock_create(&sk, PF_INET6,
1859 SOCK_RAW, IPPROTO_ICMPV6, net);
1860 if (err < 0) {
1861 ND_PRINTK(0, err,
1862 "NDISC: Failed to initialize the control socket (err %d)\n",
1863 err);
1864 return err;
1865 }
1866
1867 net->ipv6.ndisc_sk = sk;
1868
1869 np = inet6_sk(sk);
1870 np->hop_limit = 255;
1871 /* Do not loopback ndisc messages */
1872 np->mc_loop = 0;
1873
1874 return 0;
1875 }
1876
1877 static void __net_exit ndisc_net_exit(struct net *net)
1878 {
1879 inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
1880 }
1881
1882 static struct pernet_operations ndisc_net_ops = {
1883 .init = ndisc_net_init,
1884 .exit = ndisc_net_exit,
1885 };
1886
1887 int __init ndisc_init(void)
1888 {
1889 int err;
1890
1891 err = register_pernet_subsys(&ndisc_net_ops);
1892 if (err)
1893 return err;
1894 /*
1895 * Initialize the neighbour table
1896 */
1897 neigh_table_init(NEIGH_ND_TABLE, &nd_tbl);
1898
1899 #ifdef CONFIG_SYSCTL
1900 err = neigh_sysctl_register(NULL, &nd_tbl.parms,
1901 ndisc_ifinfo_sysctl_change);
1902 if (err)
1903 goto out_unregister_pernet;
1904 out:
1905 #endif
1906 return err;
1907
1908 #ifdef CONFIG_SYSCTL
1909 out_unregister_pernet:
1910 unregister_pernet_subsys(&ndisc_net_ops);
1911 goto out;
1912 #endif
1913 }
1914
1915 int __init ndisc_late_init(void)
1916 {
1917 return register_netdevice_notifier(&ndisc_netdev_notifier);
1918 }
1919
1920 void ndisc_late_cleanup(void)
1921 {
1922 unregister_netdevice_notifier(&ndisc_netdev_notifier);
1923 }
1924
1925 void ndisc_cleanup(void)
1926 {
1927 #ifdef CONFIG_SYSCTL
1928 neigh_sysctl_unregister(&nd_tbl.parms);
1929 #endif
1930 neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl);
1931 unregister_pernet_subsys(&ndisc_net_ops);
1932 }
CRIS linux kernel tree