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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Neighbour Discovery for IPv6
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 * Mike Shaver <shaver@ingenia.com>
9 */
10
11/*
12 * Changes:
13 *
14 * Alexey I. Froloff : RFC6106 (DNSSL) support
15 * Pierre Ynard : export userland ND options
16 * through netlink (RDNSS support)
17 * Lars Fenneberg : fixed MTU setting on receipt
18 * of an RA.
19 * Janos Farkas : kmalloc failure checks
20 * Alexey Kuznetsov : state machine reworked
21 * and moved to net/core.
22 * Pekka Savola : RFC2461 validation
23 * YOSHIFUJI Hideaki @USAGI : Verify ND options properly
24 */
25
26#define pr_fmt(fmt) "ICMPv6: " fmt
27
28#include <linux/module.h>
29#include <linux/errno.h>
30#include <linux/types.h>
31#include <linux/socket.h>
32#include <linux/sockios.h>
33#include <linux/sched.h>
34#include <linux/net.h>
35#include <linux/in6.h>
36#include <linux/route.h>
37#include <linux/init.h>
38#include <linux/rcupdate.h>
39#include <linux/slab.h>
40#ifdef CONFIG_SYSCTL
41#include <linux/sysctl.h>
42#endif
43
44#include <linux/if_addr.h>
45#include <linux/if_ether.h>
46#include <linux/if_arp.h>
47#include <linux/ipv6.h>
48#include <linux/icmpv6.h>
49#include <linux/jhash.h>
50
51#include <net/sock.h>
52#include <net/snmp.h>
53
54#include <net/ipv6.h>
55#include <net/protocol.h>
56#include <net/ndisc.h>
57#include <net/ip6_route.h>
58#include <net/addrconf.h>
59#include <net/icmp.h>
60
61#include <net/netlink.h>
62#include <linux/rtnetlink.h>
63
64#include <net/flow.h>
65#include <net/ip6_checksum.h>
66#include <net/inet_common.h>
67#include <linux/proc_fs.h>
68
69#include <linux/netfilter.h>
70#include <linux/netfilter_ipv6.h>
71
72static u32 ndisc_hash(const void *pkey,
73 const struct net_device *dev,
74 __u32 *hash_rnd);
75static bool ndisc_key_eq(const struct neighbour *neigh, const void *pkey);
76static bool ndisc_allow_add(const struct net_device *dev,
77 struct netlink_ext_ack *extack);
78static int ndisc_constructor(struct neighbour *neigh);
79static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
80static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
81static int pndisc_constructor(struct pneigh_entry *n);
82static void pndisc_destructor(struct pneigh_entry *n);
83static void pndisc_redo(struct sk_buff *skb);
84static int ndisc_is_multicast(const void *pkey);
85
86static const struct neigh_ops ndisc_generic_ops = {
87 .family = AF_INET6,
88 .solicit = ndisc_solicit,
89 .error_report = ndisc_error_report,
90 .output = neigh_resolve_output,
91 .connected_output = neigh_connected_output,
92};
93
94static const struct neigh_ops ndisc_hh_ops = {
95 .family = AF_INET6,
96 .solicit = ndisc_solicit,
97 .error_report = ndisc_error_report,
98 .output = neigh_resolve_output,
99 .connected_output = neigh_resolve_output,
100};
101
102
103static const struct neigh_ops ndisc_direct_ops = {
104 .family = AF_INET6,
105 .output = neigh_direct_output,
106 .connected_output = neigh_direct_output,
107};
108
109struct neigh_table nd_tbl = {
110 .family = AF_INET6,
111 .key_len = sizeof(struct in6_addr),
112 .protocol = cpu_to_be16(ETH_P_IPV6),
113 .hash = ndisc_hash,
114 .key_eq = ndisc_key_eq,
115 .constructor = ndisc_constructor,
116 .pconstructor = pndisc_constructor,
117 .pdestructor = pndisc_destructor,
118 .proxy_redo = pndisc_redo,
119 .is_multicast = ndisc_is_multicast,
120 .allow_add = ndisc_allow_add,
121 .id = "ndisc_cache",
122 .parms = {
123 .tbl = &nd_tbl,
124 .reachable_time = ND_REACHABLE_TIME,
125 .data = {
126 [NEIGH_VAR_MCAST_PROBES] = 3,
127 [NEIGH_VAR_UCAST_PROBES] = 3,
128 [NEIGH_VAR_RETRANS_TIME] = ND_RETRANS_TIMER,
129 [NEIGH_VAR_BASE_REACHABLE_TIME] = ND_REACHABLE_TIME,
130 [NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ,
131 [NEIGH_VAR_INTERVAL_PROBE_TIME_MS] = 5 * HZ,
132 [NEIGH_VAR_GC_STALETIME] = 60 * HZ,
133 [NEIGH_VAR_QUEUE_LEN_BYTES] = SK_WMEM_MAX,
134 [NEIGH_VAR_PROXY_QLEN] = 64,
135 [NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ,
136 [NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10,
137 },
138 },
139 .gc_interval = 30 * HZ,
140 .gc_thresh1 = 128,
141 .gc_thresh2 = 512,
142 .gc_thresh3 = 1024,
143};
144EXPORT_SYMBOL_GPL(nd_tbl);
145
146void __ndisc_fill_addr_option(struct sk_buff *skb, int type, const void *data,
147 int data_len, int pad)
148{
149 int space = __ndisc_opt_addr_space(data_len, pad);
150 u8 *opt = skb_put(skb, space);
151
152 opt[0] = type;
153 opt[1] = space>>3;
154
155 memset(opt + 2, 0, pad);
156 opt += pad;
157 space -= pad;
158
159 memcpy(opt+2, data, data_len);
160 data_len += 2;
161 opt += data_len;
162 space -= data_len;
163 if (space > 0)
164 memset(opt, 0, space);
165}
166EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option);
167
168static inline void ndisc_fill_addr_option(struct sk_buff *skb, int type,
169 const void *data, u8 icmp6_type)
170{
171 __ndisc_fill_addr_option(skb, type, data, skb->dev->addr_len,
172 ndisc_addr_option_pad(skb->dev->type));
173 ndisc_ops_fill_addr_option(skb->dev, skb, icmp6_type);
174}
175
176static inline void ndisc_fill_redirect_addr_option(struct sk_buff *skb,
177 void *ha,
178 const u8 *ops_data)
179{
180 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, ha, NDISC_REDIRECT);
181 ndisc_ops_fill_redirect_addr_option(skb->dev, skb, ops_data);
182}
183
184static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
185 struct nd_opt_hdr *end)
186{
187 int type;
188 if (!cur || !end || cur >= end)
189 return NULL;
190 type = cur->nd_opt_type;
191 do {
192 cur = ((void *)cur) + (cur->nd_opt_len << 3);
193 } while (cur < end && cur->nd_opt_type != type);
194 return cur <= end && cur->nd_opt_type == type ? cur : NULL;
195}
196
197static inline int ndisc_is_useropt(const struct net_device *dev,
198 struct nd_opt_hdr *opt)
199{
200 return opt->nd_opt_type == ND_OPT_PREFIX_INFO ||
201 opt->nd_opt_type == ND_OPT_RDNSS ||
202 opt->nd_opt_type == ND_OPT_DNSSL ||
203 opt->nd_opt_type == ND_OPT_6CO ||
204 opt->nd_opt_type == ND_OPT_CAPTIVE_PORTAL ||
205 opt->nd_opt_type == ND_OPT_PREF64;
206}
207
208static struct nd_opt_hdr *ndisc_next_useropt(const struct net_device *dev,
209 struct nd_opt_hdr *cur,
210 struct nd_opt_hdr *end)
211{
212 if (!cur || !end || cur >= end)
213 return NULL;
214 do {
215 cur = ((void *)cur) + (cur->nd_opt_len << 3);
216 } while (cur < end && !ndisc_is_useropt(dev, cur));
217 return cur <= end && ndisc_is_useropt(dev, cur) ? cur : NULL;
218}
219
220struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
221 u8 *opt, int opt_len,
222 struct ndisc_options *ndopts)
223{
224 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
225
226 if (!nd_opt || opt_len < 0 || !ndopts)
227 return NULL;
228 memset(ndopts, 0, sizeof(*ndopts));
229 while (opt_len) {
230 bool unknown = false;
231 int l;
232 if (opt_len < sizeof(struct nd_opt_hdr))
233 return NULL;
234 l = nd_opt->nd_opt_len << 3;
235 if (opt_len < l || l == 0)
236 return NULL;
237 if (ndisc_ops_parse_options(dev, nd_opt, ndopts))
238 goto next_opt;
239 switch (nd_opt->nd_opt_type) {
240 case ND_OPT_SOURCE_LL_ADDR:
241 case ND_OPT_TARGET_LL_ADDR:
242 case ND_OPT_MTU:
243 case ND_OPT_NONCE:
244 case ND_OPT_REDIRECT_HDR:
245 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
246 ND_PRINTK(2, warn,
247 "%s: duplicated ND6 option found: type=%d\n",
248 __func__, nd_opt->nd_opt_type);
249 } else {
250 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
251 }
252 break;
253 case ND_OPT_PREFIX_INFO:
254 ndopts->nd_opts_pi_end = nd_opt;
255 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
256 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
257 break;
258#ifdef CONFIG_IPV6_ROUTE_INFO
259 case ND_OPT_ROUTE_INFO:
260 ndopts->nd_opts_ri_end = nd_opt;
261 if (!ndopts->nd_opts_ri)
262 ndopts->nd_opts_ri = nd_opt;
263 break;
264#endif
265 default:
266 unknown = true;
267 }
268 if (ndisc_is_useropt(dev, nd_opt)) {
269 ndopts->nd_useropts_end = nd_opt;
270 if (!ndopts->nd_useropts)
271 ndopts->nd_useropts = nd_opt;
272 } else if (unknown) {
273 /*
274 * Unknown options must be silently ignored,
275 * to accommodate future extension to the
276 * protocol.
277 */
278 ND_PRINTK(2, notice,
279 "%s: ignored unsupported option; type=%d, len=%d\n",
280 __func__,
281 nd_opt->nd_opt_type,
282 nd_opt->nd_opt_len);
283 }
284next_opt:
285 opt_len -= l;
286 nd_opt = ((void *)nd_opt) + l;
287 }
288 return ndopts;
289}
290
291int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
292{
293 switch (dev->type) {
294 case ARPHRD_ETHER:
295 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
296 case ARPHRD_FDDI:
297 ipv6_eth_mc_map(addr, buf);
298 return 0;
299 case ARPHRD_ARCNET:
300 ipv6_arcnet_mc_map(addr, buf);
301 return 0;
302 case ARPHRD_INFINIBAND:
303 ipv6_ib_mc_map(addr, dev->broadcast, buf);
304 return 0;
305 case ARPHRD_IPGRE:
306 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
307 default:
308 if (dir) {
309 memcpy(buf, dev->broadcast, dev->addr_len);
310 return 0;
311 }
312 }
313 return -EINVAL;
314}
315EXPORT_SYMBOL(ndisc_mc_map);
316
317static u32 ndisc_hash(const void *pkey,
318 const struct net_device *dev,
319 __u32 *hash_rnd)
320{
321 return ndisc_hashfn(pkey, dev, hash_rnd);
322}
323
324static bool ndisc_key_eq(const struct neighbour *n, const void *pkey)
325{
326 return neigh_key_eq128(n, pkey);
327}
328
329static int ndisc_constructor(struct neighbour *neigh)
330{
331 struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key;
332 struct net_device *dev = neigh->dev;
333 struct inet6_dev *in6_dev;
334 struct neigh_parms *parms;
335 bool is_multicast = ipv6_addr_is_multicast(addr);
336
337 in6_dev = in6_dev_get(dev);
338 if (!in6_dev) {
339 return -EINVAL;
340 }
341
342 parms = in6_dev->nd_parms;
343 __neigh_parms_put(neigh->parms);
344 neigh->parms = neigh_parms_clone(parms);
345
346 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
347 if (!dev->header_ops) {
348 neigh->nud_state = NUD_NOARP;
349 neigh->ops = &ndisc_direct_ops;
350 neigh->output = neigh_direct_output;
351 } else {
352 if (is_multicast) {
353 neigh->nud_state = NUD_NOARP;
354 ndisc_mc_map(addr, neigh->ha, dev, 1);
355 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
356 neigh->nud_state = NUD_NOARP;
357 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
358 if (dev->flags&IFF_LOOPBACK)
359 neigh->type = RTN_LOCAL;
360 } else if (dev->flags&IFF_POINTOPOINT) {
361 neigh->nud_state = NUD_NOARP;
362 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
363 }
364 if (dev->header_ops->cache)
365 neigh->ops = &ndisc_hh_ops;
366 else
367 neigh->ops = &ndisc_generic_ops;
368 if (neigh->nud_state&NUD_VALID)
369 neigh->output = neigh->ops->connected_output;
370 else
371 neigh->output = neigh->ops->output;
372 }
373 in6_dev_put(in6_dev);
374 return 0;
375}
376
377static int pndisc_constructor(struct pneigh_entry *n)
378{
379 struct in6_addr *addr = (struct in6_addr *)&n->key;
380 struct in6_addr maddr;
381 struct net_device *dev = n->dev;
382
383 if (!dev || !__in6_dev_get(dev))
384 return -EINVAL;
385 addrconf_addr_solict_mult(addr, &maddr);
386 ipv6_dev_mc_inc(dev, &maddr);
387 return 0;
388}
389
390static void pndisc_destructor(struct pneigh_entry *n)
391{
392 struct in6_addr *addr = (struct in6_addr *)&n->key;
393 struct in6_addr maddr;
394 struct net_device *dev = n->dev;
395
396 if (!dev || !__in6_dev_get(dev))
397 return;
398 addrconf_addr_solict_mult(addr, &maddr);
399 ipv6_dev_mc_dec(dev, &maddr);
400}
401
402/* called with rtnl held */
403static bool ndisc_allow_add(const struct net_device *dev,
404 struct netlink_ext_ack *extack)
405{
406 struct inet6_dev *idev = __in6_dev_get(dev);
407
408 if (!idev || idev->cnf.disable_ipv6) {
409 NL_SET_ERR_MSG(extack, "IPv6 is disabled on this device");
410 return false;
411 }
412
413 return true;
414}
415
416static struct sk_buff *ndisc_alloc_skb(struct net_device *dev,
417 int len)
418{
419 int hlen = LL_RESERVED_SPACE(dev);
420 int tlen = dev->needed_tailroom;
421 struct sk_buff *skb;
422
423 skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC);
424 if (!skb)
425 return NULL;
426
427 skb->protocol = htons(ETH_P_IPV6);
428 skb->dev = dev;
429
430 skb_reserve(skb, hlen + sizeof(struct ipv6hdr));
431 skb_reset_transport_header(skb);
432
433 /* Manually assign socket ownership as we avoid calling
434 * sock_alloc_send_pskb() to bypass wmem buffer limits
435 */
436 rcu_read_lock();
437 skb_set_owner_w(skb, dev_net_rcu(dev)->ipv6.ndisc_sk);
438 rcu_read_unlock();
439
440 return skb;
441}
442
443static void ip6_nd_hdr(struct sk_buff *skb,
444 const struct in6_addr *saddr,
445 const struct in6_addr *daddr,
446 int hop_limit, int len)
447{
448 struct ipv6hdr *hdr;
449 struct inet6_dev *idev;
450 unsigned tclass;
451
452 rcu_read_lock();
453 idev = __in6_dev_get(skb->dev);
454 tclass = idev ? READ_ONCE(idev->cnf.ndisc_tclass) : 0;
455 rcu_read_unlock();
456
457 skb_push(skb, sizeof(*hdr));
458 skb_reset_network_header(skb);
459 hdr = ipv6_hdr(skb);
460
461 ip6_flow_hdr(hdr, tclass, 0);
462
463 hdr->payload_len = htons(len);
464 hdr->nexthdr = IPPROTO_ICMPV6;
465 hdr->hop_limit = hop_limit;
466
467 hdr->saddr = *saddr;
468 hdr->daddr = *daddr;
469}
470
471void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr,
472 const struct in6_addr *saddr)
473{
474 struct icmp6hdr *icmp6h = icmp6_hdr(skb);
475 struct dst_entry *dst = skb_dst(skb);
476 struct inet6_dev *idev;
477 struct net *net;
478 struct sock *sk;
479 int err;
480 u8 type;
481
482 type = icmp6h->icmp6_type;
483
484 rcu_read_lock();
485
486 net = dev_net_rcu(skb->dev);
487 sk = net->ipv6.ndisc_sk;
488 if (!dst) {
489 struct flowi6 fl6;
490 int oif = skb->dev->ifindex;
491
492 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif);
493 dst = icmp6_dst_alloc(skb->dev, &fl6);
494 if (IS_ERR(dst)) {
495 rcu_read_unlock();
496 kfree_skb(skb);
497 return;
498 }
499
500 skb_dst_set(skb, dst);
501 }
502
503 icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len,
504 IPPROTO_ICMPV6,
505 csum_partial(icmp6h,
506 skb->len, 0));
507
508 ip6_nd_hdr(skb, saddr, daddr, READ_ONCE(inet6_sk(sk)->hop_limit), skb->len);
509
510 idev = __in6_dev_get(dst->dev);
511 IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
512
513 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
514 net, sk, skb, NULL, dst->dev,
515 dst_output);
516 if (!err) {
517 ICMP6MSGOUT_INC_STATS(net, idev, type);
518 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
519 }
520
521 rcu_read_unlock();
522}
523EXPORT_SYMBOL(ndisc_send_skb);
524
525void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
526 const struct in6_addr *solicited_addr,
527 bool router, bool solicited, bool override, bool inc_opt)
528{
529 struct sk_buff *skb;
530 struct in6_addr tmpaddr;
531 struct inet6_ifaddr *ifp;
532 const struct in6_addr *src_addr;
533 struct nd_msg *msg;
534 int optlen = 0;
535
536 /* for anycast or proxy, solicited_addr != src_addr */
537 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
538 if (ifp) {
539 src_addr = solicited_addr;
540 if (ifp->flags & IFA_F_OPTIMISTIC)
541 override = false;
542 inc_opt |= READ_ONCE(ifp->idev->cnf.force_tllao);
543 in6_ifa_put(ifp);
544 } else {
545 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
546 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
547 &tmpaddr))
548 return;
549 src_addr = &tmpaddr;
550 }
551
552 if (!dev->addr_len)
553 inc_opt = false;
554 if (inc_opt)
555 optlen += ndisc_opt_addr_space(dev,
556 NDISC_NEIGHBOUR_ADVERTISEMENT);
557
558 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
559 if (!skb)
560 return;
561
562 msg = skb_put(skb, sizeof(*msg));
563 *msg = (struct nd_msg) {
564 .icmph = {
565 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
566 .icmp6_router = router,
567 .icmp6_solicited = solicited,
568 .icmp6_override = override,
569 },
570 .target = *solicited_addr,
571 };
572
573 if (inc_opt)
574 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
575 dev->dev_addr,
576 NDISC_NEIGHBOUR_ADVERTISEMENT);
577
578 ndisc_send_skb(skb, daddr, src_addr);
579}
580
581static void ndisc_send_unsol_na(struct net_device *dev)
582{
583 struct inet6_dev *idev;
584 struct inet6_ifaddr *ifa;
585
586 idev = in6_dev_get(dev);
587 if (!idev)
588 return;
589
590 read_lock_bh(&idev->lock);
591 list_for_each_entry(ifa, &idev->addr_list, if_list) {
592 /* skip tentative addresses until dad completes */
593 if (ifa->flags & IFA_F_TENTATIVE &&
594 !(ifa->flags & IFA_F_OPTIMISTIC))
595 continue;
596
597 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifa->addr,
598 /*router=*/ !!idev->cnf.forwarding,
599 /*solicited=*/ false, /*override=*/ true,
600 /*inc_opt=*/ true);
601 }
602 read_unlock_bh(&idev->lock);
603
604 in6_dev_put(idev);
605}
606
607struct sk_buff *ndisc_ns_create(struct net_device *dev, const struct in6_addr *solicit,
608 const struct in6_addr *saddr, u64 nonce)
609{
610 int inc_opt = dev->addr_len;
611 struct sk_buff *skb;
612 struct nd_msg *msg;
613 int optlen = 0;
614
615 if (!saddr)
616 return NULL;
617
618 if (ipv6_addr_any(saddr))
619 inc_opt = false;
620 if (inc_opt)
621 optlen += ndisc_opt_addr_space(dev,
622 NDISC_NEIGHBOUR_SOLICITATION);
623 if (nonce != 0)
624 optlen += 8;
625
626 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
627 if (!skb)
628 return NULL;
629
630 msg = skb_put(skb, sizeof(*msg));
631 *msg = (struct nd_msg) {
632 .icmph = {
633 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
634 },
635 .target = *solicit,
636 };
637
638 if (inc_opt)
639 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
640 dev->dev_addr,
641 NDISC_NEIGHBOUR_SOLICITATION);
642 if (nonce != 0) {
643 u8 *opt = skb_put(skb, 8);
644
645 opt[0] = ND_OPT_NONCE;
646 opt[1] = 8 >> 3;
647 memcpy(opt + 2, &nonce, 6);
648 }
649
650 return skb;
651}
652EXPORT_SYMBOL(ndisc_ns_create);
653
654void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
655 const struct in6_addr *daddr, const struct in6_addr *saddr,
656 u64 nonce)
657{
658 struct in6_addr addr_buf;
659 struct sk_buff *skb;
660
661 if (!saddr) {
662 if (ipv6_get_lladdr(dev, &addr_buf,
663 (IFA_F_TENTATIVE | IFA_F_OPTIMISTIC)))
664 return;
665 saddr = &addr_buf;
666 }
667
668 skb = ndisc_ns_create(dev, solicit, saddr, nonce);
669
670 if (skb)
671 ndisc_send_skb(skb, daddr, saddr);
672}
673
674void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
675 const struct in6_addr *daddr)
676{
677 struct sk_buff *skb;
678 struct rs_msg *msg;
679 int send_sllao = dev->addr_len;
680 int optlen = 0;
681
682#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
683 /*
684 * According to section 2.2 of RFC 4429, we must not
685 * send router solicitations with a sllao from
686 * optimistic addresses, but we may send the solicitation
687 * if we don't include the sllao. So here we check
688 * if our address is optimistic, and if so, we
689 * suppress the inclusion of the sllao.
690 */
691 if (send_sllao) {
692 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
693 dev, 1);
694 if (ifp) {
695 if (ifp->flags & IFA_F_OPTIMISTIC) {
696 send_sllao = 0;
697 }
698 in6_ifa_put(ifp);
699 } else {
700 send_sllao = 0;
701 }
702 }
703#endif
704 if (send_sllao)
705 optlen += ndisc_opt_addr_space(dev, NDISC_ROUTER_SOLICITATION);
706
707 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
708 if (!skb)
709 return;
710
711 msg = skb_put(skb, sizeof(*msg));
712 *msg = (struct rs_msg) {
713 .icmph = {
714 .icmp6_type = NDISC_ROUTER_SOLICITATION,
715 },
716 };
717
718 if (send_sllao)
719 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
720 dev->dev_addr,
721 NDISC_ROUTER_SOLICITATION);
722
723 ndisc_send_skb(skb, daddr, saddr);
724}
725
726
727static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
728{
729 /*
730 * "The sender MUST return an ICMP
731 * destination unreachable"
732 */
733 dst_link_failure(skb);
734 kfree_skb(skb);
735}
736
737/* Called with locked neigh: either read or both */
738
739static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
740{
741 struct in6_addr *saddr = NULL;
742 struct in6_addr mcaddr;
743 struct net_device *dev = neigh->dev;
744 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
745 int probes = atomic_read(&neigh->probes);
746
747 if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr,
748 dev, false, 1,
749 IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))
750 saddr = &ipv6_hdr(skb)->saddr;
751 probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES);
752 if (probes < 0) {
753 if (!(READ_ONCE(neigh->nud_state) & NUD_VALID)) {
754 ND_PRINTK(1, dbg,
755 "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
756 __func__, target);
757 }
758 ndisc_send_ns(dev, target, target, saddr, 0);
759 } else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) {
760 neigh_app_ns(neigh);
761 } else {
762 addrconf_addr_solict_mult(target, &mcaddr);
763 ndisc_send_ns(dev, target, &mcaddr, saddr, 0);
764 }
765}
766
767static int pndisc_is_router(const void *pkey,
768 struct net_device *dev)
769{
770 struct pneigh_entry *n;
771 int ret = -1;
772
773 read_lock_bh(&nd_tbl.lock);
774 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
775 if (n)
776 ret = !!(n->flags & NTF_ROUTER);
777 read_unlock_bh(&nd_tbl.lock);
778
779 return ret;
780}
781
782void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
783 const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
784 struct ndisc_options *ndopts)
785{
786 neigh_update(neigh, lladdr, new, flags, 0);
787 /* report ndisc ops about neighbour update */
788 ndisc_ops_update(dev, neigh, flags, icmp6_type, ndopts);
789}
790
791static enum skb_drop_reason ndisc_recv_ns(struct sk_buff *skb)
792{
793 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
794 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
795 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
796 u8 *lladdr = NULL;
797 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
798 offsetof(struct nd_msg, opt));
799 struct ndisc_options ndopts;
800 struct net_device *dev = skb->dev;
801 struct inet6_ifaddr *ifp;
802 struct inet6_dev *idev = NULL;
803 struct neighbour *neigh;
804 int dad = ipv6_addr_any(saddr);
805 int is_router = -1;
806 SKB_DR(reason);
807 u64 nonce = 0;
808 bool inc;
809
810 if (skb->len < sizeof(struct nd_msg))
811 return SKB_DROP_REASON_PKT_TOO_SMALL;
812
813 if (ipv6_addr_is_multicast(&msg->target)) {
814 ND_PRINTK(2, warn, "NS: multicast target address\n");
815 return reason;
816 }
817
818 /*
819 * RFC2461 7.1.1:
820 * DAD has to be destined for solicited node multicast address.
821 */
822 if (dad && !ipv6_addr_is_solict_mult(daddr)) {
823 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n");
824 return reason;
825 }
826
827 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts))
828 return SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS;
829
830 if (ndopts.nd_opts_src_lladdr) {
831 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
832 if (!lladdr) {
833 ND_PRINTK(2, warn,
834 "NS: invalid link-layer address length\n");
835 return reason;
836 }
837
838 /* RFC2461 7.1.1:
839 * If the IP source address is the unspecified address,
840 * there MUST NOT be source link-layer address option
841 * in the message.
842 */
843 if (dad) {
844 ND_PRINTK(2, warn,
845 "NS: bad DAD packet (link-layer address option)\n");
846 return reason;
847 }
848 }
849 if (ndopts.nd_opts_nonce && ndopts.nd_opts_nonce->nd_opt_len == 1)
850 memcpy(&nonce, (u8 *)(ndopts.nd_opts_nonce + 1), 6);
851
852 inc = ipv6_addr_is_multicast(daddr);
853
854 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
855 if (ifp) {
856have_ifp:
857 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
858 if (dad) {
859 if (nonce != 0 && ifp->dad_nonce == nonce) {
860 u8 *np = (u8 *)&nonce;
861 /* Matching nonce if looped back */
862 ND_PRINTK(2, notice,
863 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n",
864 ifp->idev->dev->name,
865 &ifp->addr, np);
866 goto out;
867 }
868 /*
869 * We are colliding with another node
870 * who is doing DAD
871 * so fail our DAD process
872 */
873 addrconf_dad_failure(skb, ifp);
874 return reason;
875 } else {
876 /*
877 * This is not a dad solicitation.
878 * If we are an optimistic node,
879 * we should respond.
880 * Otherwise, we should ignore it.
881 */
882 if (!(ifp->flags & IFA_F_OPTIMISTIC))
883 goto out;
884 }
885 }
886
887 idev = ifp->idev;
888 } else {
889 struct net *net = dev_net(dev);
890
891 /* perhaps an address on the master device */
892 if (netif_is_l3_slave(dev)) {
893 struct net_device *mdev;
894
895 mdev = netdev_master_upper_dev_get_rcu(dev);
896 if (mdev) {
897 ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1);
898 if (ifp)
899 goto have_ifp;
900 }
901 }
902
903 idev = in6_dev_get(dev);
904 if (!idev) {
905 /* XXX: count this drop? */
906 return reason;
907 }
908
909 if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
910 (READ_ONCE(idev->cnf.forwarding) &&
911 (READ_ONCE(net->ipv6.devconf_all->proxy_ndp) ||
912 READ_ONCE(idev->cnf.proxy_ndp)) &&
913 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
914 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
915 skb->pkt_type != PACKET_HOST &&
916 inc &&
917 NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) {
918 /*
919 * for anycast or proxy,
920 * sender should delay its response
921 * by a random time between 0 and
922 * MAX_ANYCAST_DELAY_TIME seconds.
923 * (RFC2461) -- yoshfuji
924 */
925 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
926 if (n)
927 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
928 goto out;
929 }
930 } else {
931 SKB_DR_SET(reason, IPV6_NDISC_NS_OTHERHOST);
932 goto out;
933 }
934 }
935
936 if (is_router < 0)
937 is_router = READ_ONCE(idev->cnf.forwarding);
938
939 if (dad) {
940 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target,
941 !!is_router, false, (ifp != NULL), true);
942 goto out;
943 }
944
945 if (inc)
946 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
947 else
948 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
949
950 /*
951 * update / create cache entry
952 * for the source address
953 */
954 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
955 !inc || lladdr || !dev->addr_len);
956 if (neigh)
957 ndisc_update(dev, neigh, lladdr, NUD_STALE,
958 NEIGH_UPDATE_F_WEAK_OVERRIDE|
959 NEIGH_UPDATE_F_OVERRIDE,
960 NDISC_NEIGHBOUR_SOLICITATION, &ndopts);
961 if (neigh || !dev->header_ops) {
962 ndisc_send_na(dev, saddr, &msg->target, !!is_router,
963 true, (ifp != NULL && inc), inc);
964 if (neigh)
965 neigh_release(neigh);
966 reason = SKB_CONSUMED;
967 }
968
969out:
970 if (ifp)
971 in6_ifa_put(ifp);
972 else
973 in6_dev_put(idev);
974 return reason;
975}
976
977static int accept_untracked_na(struct net_device *dev, struct in6_addr *saddr)
978{
979 struct inet6_dev *idev = __in6_dev_get(dev);
980
981 switch (READ_ONCE(idev->cnf.accept_untracked_na)) {
982 case 0: /* Don't accept untracked na (absent in neighbor cache) */
983 return 0;
984 case 1: /* Create new entries from na if currently untracked */
985 return 1;
986 case 2: /* Create new entries from untracked na only if saddr is in the
987 * same subnet as an address configured on the interface that
988 * received the na
989 */
990 return !!ipv6_chk_prefix(saddr, dev);
991 default:
992 return 0;
993 }
994}
995
996static enum skb_drop_reason ndisc_recv_na(struct sk_buff *skb)
997{
998 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
999 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
1000 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
1001 u8 *lladdr = NULL;
1002 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
1003 offsetof(struct nd_msg, opt));
1004 struct ndisc_options ndopts;
1005 struct net_device *dev = skb->dev;
1006 struct inet6_dev *idev = __in6_dev_get(dev);
1007 struct inet6_ifaddr *ifp;
1008 struct neighbour *neigh;
1009 SKB_DR(reason);
1010 u8 new_state;
1011
1012 if (skb->len < sizeof(struct nd_msg))
1013 return SKB_DROP_REASON_PKT_TOO_SMALL;
1014
1015 if (ipv6_addr_is_multicast(&msg->target)) {
1016 ND_PRINTK(2, warn, "NA: target address is multicast\n");
1017 return reason;
1018 }
1019
1020 if (ipv6_addr_is_multicast(daddr) &&
1021 msg->icmph.icmp6_solicited) {
1022 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n");
1023 return reason;
1024 }
1025
1026 /* For some 802.11 wireless deployments (and possibly other networks),
1027 * there will be a NA proxy and unsolicitd packets are attacks
1028 * and thus should not be accepted.
1029 * drop_unsolicited_na takes precedence over accept_untracked_na
1030 */
1031 if (!msg->icmph.icmp6_solicited && idev &&
1032 READ_ONCE(idev->cnf.drop_unsolicited_na))
1033 return reason;
1034
1035 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts))
1036 return SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS;
1037
1038 if (ndopts.nd_opts_tgt_lladdr) {
1039 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
1040 if (!lladdr) {
1041 ND_PRINTK(2, warn,
1042 "NA: invalid link-layer address length\n");
1043 return reason;
1044 }
1045 }
1046 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
1047 if (ifp) {
1048 if (skb->pkt_type != PACKET_LOOPBACK
1049 && (ifp->flags & IFA_F_TENTATIVE)) {
1050 addrconf_dad_failure(skb, ifp);
1051 return reason;
1052 }
1053 /* What should we make now? The advertisement
1054 is invalid, but ndisc specs say nothing
1055 about it. It could be misconfiguration, or
1056 an smart proxy agent tries to help us :-)
1057
1058 We should not print the error if NA has been
1059 received from loopback - it is just our own
1060 unsolicited advertisement.
1061 */
1062 if (skb->pkt_type != PACKET_LOOPBACK)
1063 ND_PRINTK(1, warn,
1064 "NA: %pM advertised our address %pI6c on %s!\n",
1065 eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name);
1066 in6_ifa_put(ifp);
1067 return reason;
1068 }
1069
1070 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
1071
1072 /* RFC 9131 updates original Neighbour Discovery RFC 4861.
1073 * NAs with Target LL Address option without a corresponding
1074 * entry in the neighbour cache can now create a STALE neighbour
1075 * cache entry on routers.
1076 *
1077 * entry accept fwding solicited behaviour
1078 * ------- ------ ------ --------- ----------------------
1079 * present X X 0 Set state to STALE
1080 * present X X 1 Set state to REACHABLE
1081 * absent 0 X X Do nothing
1082 * absent 1 0 X Do nothing
1083 * absent 1 1 X Add a new STALE entry
1084 *
1085 * Note that we don't do a (daddr == all-routers-mcast) check.
1086 */
1087 new_state = msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE;
1088 if (!neigh && lladdr && idev && READ_ONCE(idev->cnf.forwarding)) {
1089 if (accept_untracked_na(dev, saddr)) {
1090 neigh = neigh_create(&nd_tbl, &msg->target, dev);
1091 new_state = NUD_STALE;
1092 }
1093 }
1094
1095 if (neigh && !IS_ERR(neigh)) {
1096 u8 old_flags = neigh->flags;
1097 struct net *net = dev_net(dev);
1098
1099 if (READ_ONCE(neigh->nud_state) & NUD_FAILED)
1100 goto out;
1101
1102 /*
1103 * Don't update the neighbor cache entry on a proxy NA from
1104 * ourselves because either the proxied node is off link or it
1105 * has already sent a NA to us.
1106 */
1107 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
1108 READ_ONCE(net->ipv6.devconf_all->forwarding) &&
1109 READ_ONCE(net->ipv6.devconf_all->proxy_ndp) &&
1110 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
1111 /* XXX: idev->cnf.proxy_ndp */
1112 goto out;
1113 }
1114
1115 ndisc_update(dev, neigh, lladdr,
1116 new_state,
1117 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1118 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
1119 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1120 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0),
1121 NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts);
1122
1123 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
1124 /*
1125 * Change: router to host
1126 */
1127 rt6_clean_tohost(dev_net(dev), saddr);
1128 }
1129 reason = SKB_CONSUMED;
1130out:
1131 neigh_release(neigh);
1132 }
1133 return reason;
1134}
1135
1136static enum skb_drop_reason ndisc_recv_rs(struct sk_buff *skb)
1137{
1138 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
1139 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
1140 struct neighbour *neigh;
1141 struct inet6_dev *idev;
1142 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
1143 struct ndisc_options ndopts;
1144 u8 *lladdr = NULL;
1145 SKB_DR(reason);
1146
1147 if (skb->len < sizeof(*rs_msg))
1148 return SKB_DROP_REASON_PKT_TOO_SMALL;
1149
1150 idev = __in6_dev_get(skb->dev);
1151 if (!idev) {
1152 ND_PRINTK(1, err, "RS: can't find in6 device\n");
1153 return reason;
1154 }
1155
1156 /* Don't accept RS if we're not in router mode */
1157 if (!READ_ONCE(idev->cnf.forwarding))
1158 goto out;
1159
1160 /*
1161 * Don't update NCE if src = ::;
1162 * this implies that the source node has no ip address assigned yet.
1163 */
1164 if (ipv6_addr_any(saddr))
1165 goto out;
1166
1167 /* Parse ND options */
1168 if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts))
1169 return SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS;
1170
1171 if (ndopts.nd_opts_src_lladdr) {
1172 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1173 skb->dev);
1174 if (!lladdr)
1175 goto out;
1176 }
1177
1178 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1179 if (neigh) {
1180 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1181 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1182 NEIGH_UPDATE_F_OVERRIDE|
1183 NEIGH_UPDATE_F_OVERRIDE_ISROUTER,
1184 NDISC_ROUTER_SOLICITATION, &ndopts);
1185 neigh_release(neigh);
1186 reason = SKB_CONSUMED;
1187 }
1188out:
1189 return reason;
1190}
1191
1192static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1193{
1194 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1195 struct sk_buff *skb;
1196 struct nlmsghdr *nlh;
1197 struct nduseroptmsg *ndmsg;
1198 struct net *net = dev_net(ra->dev);
1199 int err;
1200 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1201 + (opt->nd_opt_len << 3));
1202 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1203
1204 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1205 if (!skb) {
1206 err = -ENOBUFS;
1207 goto errout;
1208 }
1209
1210 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1211 if (!nlh) {
1212 goto nla_put_failure;
1213 }
1214
1215 ndmsg = nlmsg_data(nlh);
1216 ndmsg->nduseropt_family = AF_INET6;
1217 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1218 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1219 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1220 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1221
1222 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1223
1224 if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr))
1225 goto nla_put_failure;
1226 nlmsg_end(skb, nlh);
1227
1228 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1229 return;
1230
1231nla_put_failure:
1232 nlmsg_free(skb);
1233 err = -EMSGSIZE;
1234errout:
1235 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1236}
1237
1238static enum skb_drop_reason ndisc_router_discovery(struct sk_buff *skb)
1239{
1240 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1241 bool send_ifinfo_notify = false;
1242 struct neighbour *neigh = NULL;
1243 struct ndisc_options ndopts;
1244 struct fib6_info *rt = NULL;
1245 struct inet6_dev *in6_dev;
1246 struct fib6_table *table;
1247 u32 defrtr_usr_metric;
1248 unsigned int pref = 0;
1249 __u32 old_if_flags;
1250 struct net *net;
1251 SKB_DR(reason);
1252 int lifetime;
1253 int optlen;
1254
1255 __u8 *opt = (__u8 *)(ra_msg + 1);
1256
1257 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) -
1258 sizeof(struct ra_msg);
1259
1260 ND_PRINTK(2, info,
1261 "RA: %s, dev: %s\n",
1262 __func__, skb->dev->name);
1263 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1264 ND_PRINTK(2, warn, "RA: source address is not link-local\n");
1265 return reason;
1266 }
1267 if (optlen < 0)
1268 return SKB_DROP_REASON_PKT_TOO_SMALL;
1269
1270#ifdef CONFIG_IPV6_NDISC_NODETYPE
1271 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1272 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n");
1273 return reason;
1274 }
1275#endif
1276
1277 in6_dev = __in6_dev_get(skb->dev);
1278 if (!in6_dev) {
1279 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n",
1280 skb->dev->name);
1281 return reason;
1282 }
1283
1284 if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts))
1285 return SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS;
1286
1287 if (!ipv6_accept_ra(in6_dev)) {
1288 ND_PRINTK(2, info,
1289 "RA: %s, did not accept ra for dev: %s\n",
1290 __func__, skb->dev->name);
1291 goto skip_linkparms;
1292 }
1293
1294#ifdef CONFIG_IPV6_NDISC_NODETYPE
1295 /* skip link-specific parameters from interior routers */
1296 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1297 ND_PRINTK(2, info,
1298 "RA: %s, nodetype is NODEFAULT, dev: %s\n",
1299 __func__, skb->dev->name);
1300 goto skip_linkparms;
1301 }
1302#endif
1303
1304 if (in6_dev->if_flags & IF_RS_SENT) {
1305 /*
1306 * flag that an RA was received after an RS was sent
1307 * out on this interface.
1308 */
1309 in6_dev->if_flags |= IF_RA_RCVD;
1310 }
1311
1312 /*
1313 * Remember the managed/otherconf flags from most recently
1314 * received RA message (RFC 2462) -- yoshfuji
1315 */
1316 old_if_flags = in6_dev->if_flags;
1317 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1318 IF_RA_OTHERCONF)) |
1319 (ra_msg->icmph.icmp6_addrconf_managed ?
1320 IF_RA_MANAGED : 0) |
1321 (ra_msg->icmph.icmp6_addrconf_other ?
1322 IF_RA_OTHERCONF : 0);
1323
1324 if (old_if_flags != in6_dev->if_flags)
1325 send_ifinfo_notify = true;
1326
1327 if (!READ_ONCE(in6_dev->cnf.accept_ra_defrtr)) {
1328 ND_PRINTK(2, info,
1329 "RA: %s, defrtr is false for dev: %s\n",
1330 __func__, skb->dev->name);
1331 goto skip_defrtr;
1332 }
1333
1334 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1335 if (lifetime != 0 &&
1336 lifetime < READ_ONCE(in6_dev->cnf.accept_ra_min_lft)) {
1337 ND_PRINTK(2, info,
1338 "RA: router lifetime (%ds) is too short: %s\n",
1339 lifetime, skb->dev->name);
1340 goto skip_defrtr;
1341 }
1342
1343 /* Do not accept RA with source-addr found on local machine unless
1344 * accept_ra_from_local is set to true.
1345 */
1346 net = dev_net(in6_dev->dev);
1347 if (!READ_ONCE(in6_dev->cnf.accept_ra_from_local) &&
1348 ipv6_chk_addr(net, &ipv6_hdr(skb)->saddr, in6_dev->dev, 0)) {
1349 ND_PRINTK(2, info,
1350 "RA from local address detected on dev: %s: default router ignored\n",
1351 skb->dev->name);
1352 goto skip_defrtr;
1353 }
1354
1355#ifdef CONFIG_IPV6_ROUTER_PREF
1356 pref = ra_msg->icmph.icmp6_router_pref;
1357 /* 10b is handled as if it were 00b (medium) */
1358 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1359 !READ_ONCE(in6_dev->cnf.accept_ra_rtr_pref))
1360 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1361#endif
1362 /* routes added from RAs do not use nexthop objects */
1363 rt = rt6_get_dflt_router(net, &ipv6_hdr(skb)->saddr, skb->dev);
1364 if (rt) {
1365 neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6,
1366 rt->fib6_nh->fib_nh_dev, NULL,
1367 &ipv6_hdr(skb)->saddr);
1368 if (!neigh) {
1369 ND_PRINTK(0, err,
1370 "RA: %s got default router without neighbour\n",
1371 __func__);
1372 fib6_info_release(rt);
1373 return reason;
1374 }
1375 }
1376 /* Set default route metric as specified by user */
1377 defrtr_usr_metric = in6_dev->cnf.ra_defrtr_metric;
1378 /* delete the route if lifetime is 0 or if metric needs change */
1379 if (rt && (lifetime == 0 || rt->fib6_metric != defrtr_usr_metric)) {
1380 ip6_del_rt(net, rt, false);
1381 rt = NULL;
1382 }
1383
1384 ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, metric: %d, for dev: %s\n",
1385 rt, lifetime, defrtr_usr_metric, skb->dev->name);
1386 if (!rt && lifetime) {
1387 ND_PRINTK(3, info, "RA: adding default router\n");
1388
1389 if (neigh)
1390 neigh_release(neigh);
1391
1392 rt = rt6_add_dflt_router(net, &ipv6_hdr(skb)->saddr,
1393 skb->dev, pref, defrtr_usr_metric,
1394 lifetime);
1395 if (!rt) {
1396 ND_PRINTK(0, err,
1397 "RA: %s failed to add default route\n",
1398 __func__);
1399 return reason;
1400 }
1401
1402 neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6,
1403 rt->fib6_nh->fib_nh_dev, NULL,
1404 &ipv6_hdr(skb)->saddr);
1405 if (!neigh) {
1406 ND_PRINTK(0, err,
1407 "RA: %s got default router without neighbour\n",
1408 __func__);
1409 fib6_info_release(rt);
1410 return reason;
1411 }
1412 neigh->flags |= NTF_ROUTER;
1413 } else if (rt && IPV6_EXTRACT_PREF(rt->fib6_flags) != pref) {
1414 struct nl_info nlinfo = {
1415 .nl_net = net,
1416 };
1417 rt->fib6_flags = (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1418 inet6_rt_notify(RTM_NEWROUTE, rt, &nlinfo, NLM_F_REPLACE);
1419 }
1420
1421 if (rt) {
1422 table = rt->fib6_table;
1423 spin_lock_bh(&table->tb6_lock);
1424
1425 fib6_set_expires(rt, jiffies + (HZ * lifetime));
1426 fib6_add_gc_list(rt);
1427
1428 spin_unlock_bh(&table->tb6_lock);
1429 }
1430 if (READ_ONCE(in6_dev->cnf.accept_ra_min_hop_limit) < 256 &&
1431 ra_msg->icmph.icmp6_hop_limit) {
1432 if (READ_ONCE(in6_dev->cnf.accept_ra_min_hop_limit) <=
1433 ra_msg->icmph.icmp6_hop_limit) {
1434 WRITE_ONCE(in6_dev->cnf.hop_limit,
1435 ra_msg->icmph.icmp6_hop_limit);
1436 fib6_metric_set(rt, RTAX_HOPLIMIT,
1437 ra_msg->icmph.icmp6_hop_limit);
1438 } else {
1439 ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n");
1440 }
1441 }
1442
1443skip_defrtr:
1444
1445 /*
1446 * Update Reachable Time and Retrans Timer
1447 */
1448
1449 if (in6_dev->nd_parms) {
1450 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1451
1452 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1453 rtime = (rtime*HZ)/1000;
1454 if (rtime < HZ/100)
1455 rtime = HZ/100;
1456 NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime);
1457 in6_dev->tstamp = jiffies;
1458 send_ifinfo_notify = true;
1459 }
1460
1461 rtime = ntohl(ra_msg->reachable_time);
1462 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1463 rtime = (rtime*HZ)/1000;
1464
1465 if (rtime < HZ/10)
1466 rtime = HZ/10;
1467
1468 if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) {
1469 NEIGH_VAR_SET(in6_dev->nd_parms,
1470 BASE_REACHABLE_TIME, rtime);
1471 NEIGH_VAR_SET(in6_dev->nd_parms,
1472 GC_STALETIME, 3 * rtime);
1473 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1474 in6_dev->tstamp = jiffies;
1475 send_ifinfo_notify = true;
1476 }
1477 }
1478 }
1479
1480skip_linkparms:
1481
1482 /*
1483 * Process options.
1484 */
1485
1486 if (!neigh)
1487 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1488 skb->dev, 1);
1489 if (neigh) {
1490 u8 *lladdr = NULL;
1491 if (ndopts.nd_opts_src_lladdr) {
1492 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1493 skb->dev);
1494 if (!lladdr) {
1495 ND_PRINTK(2, warn,
1496 "RA: invalid link-layer address length\n");
1497 goto out;
1498 }
1499 }
1500 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1501 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1502 NEIGH_UPDATE_F_OVERRIDE|
1503 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1504 NEIGH_UPDATE_F_ISROUTER,
1505 NDISC_ROUTER_ADVERTISEMENT, &ndopts);
1506 reason = SKB_CONSUMED;
1507 }
1508
1509 if (!ipv6_accept_ra(in6_dev)) {
1510 ND_PRINTK(2, info,
1511 "RA: %s, accept_ra is false for dev: %s\n",
1512 __func__, skb->dev->name);
1513 goto out;
1514 }
1515
1516#ifdef CONFIG_IPV6_ROUTE_INFO
1517 if (!READ_ONCE(in6_dev->cnf.accept_ra_from_local) &&
1518 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
1519 in6_dev->dev, 0)) {
1520 ND_PRINTK(2, info,
1521 "RA from local address detected on dev: %s: router info ignored.\n",
1522 skb->dev->name);
1523 goto skip_routeinfo;
1524 }
1525
1526 if (READ_ONCE(in6_dev->cnf.accept_ra_rtr_pref) && ndopts.nd_opts_ri) {
1527 struct nd_opt_hdr *p;
1528 for (p = ndopts.nd_opts_ri;
1529 p;
1530 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1531 struct route_info *ri = (struct route_info *)p;
1532#ifdef CONFIG_IPV6_NDISC_NODETYPE
1533 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1534 ri->prefix_len == 0)
1535 continue;
1536#endif
1537 if (ri->prefix_len == 0 &&
1538 !READ_ONCE(in6_dev->cnf.accept_ra_defrtr))
1539 continue;
1540 if (ri->lifetime != 0 &&
1541 ntohl(ri->lifetime) < READ_ONCE(in6_dev->cnf.accept_ra_min_lft))
1542 continue;
1543 if (ri->prefix_len < READ_ONCE(in6_dev->cnf.accept_ra_rt_info_min_plen))
1544 continue;
1545 if (ri->prefix_len > READ_ONCE(in6_dev->cnf.accept_ra_rt_info_max_plen))
1546 continue;
1547 rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3,
1548 &ipv6_hdr(skb)->saddr);
1549 }
1550 }
1551
1552skip_routeinfo:
1553#endif
1554
1555#ifdef CONFIG_IPV6_NDISC_NODETYPE
1556 /* skip link-specific ndopts from interior routers */
1557 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1558 ND_PRINTK(2, info,
1559 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n",
1560 __func__, skb->dev->name);
1561 goto out;
1562 }
1563#endif
1564
1565 if (READ_ONCE(in6_dev->cnf.accept_ra_pinfo) && ndopts.nd_opts_pi) {
1566 struct nd_opt_hdr *p;
1567 for (p = ndopts.nd_opts_pi;
1568 p;
1569 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1570 addrconf_prefix_rcv(skb->dev, (u8 *)p,
1571 (p->nd_opt_len) << 3,
1572 ndopts.nd_opts_src_lladdr != NULL);
1573 }
1574 }
1575
1576 if (ndopts.nd_opts_mtu && READ_ONCE(in6_dev->cnf.accept_ra_mtu)) {
1577 __be32 n;
1578 u32 mtu;
1579
1580 memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1581 mtu = ntohl(n);
1582
1583 if (in6_dev->ra_mtu != mtu) {
1584 in6_dev->ra_mtu = mtu;
1585 send_ifinfo_notify = true;
1586 }
1587
1588 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1589 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu);
1590 } else if (READ_ONCE(in6_dev->cnf.mtu6) != mtu) {
1591 WRITE_ONCE(in6_dev->cnf.mtu6, mtu);
1592 fib6_metric_set(rt, RTAX_MTU, mtu);
1593 rt6_mtu_change(skb->dev, mtu);
1594 }
1595 }
1596
1597 if (ndopts.nd_useropts) {
1598 struct nd_opt_hdr *p;
1599 for (p = ndopts.nd_useropts;
1600 p;
1601 p = ndisc_next_useropt(skb->dev, p,
1602 ndopts.nd_useropts_end)) {
1603 ndisc_ra_useropt(skb, p);
1604 }
1605 }
1606
1607 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1608 ND_PRINTK(2, warn, "RA: invalid RA options\n");
1609 }
1610out:
1611 /* Send a notify if RA changed managed/otherconf flags or
1612 * timer settings or ra_mtu value
1613 */
1614 if (send_ifinfo_notify)
1615 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1616
1617 fib6_info_release(rt);
1618 if (neigh)
1619 neigh_release(neigh);
1620 return reason;
1621}
1622
1623static enum skb_drop_reason ndisc_redirect_rcv(struct sk_buff *skb)
1624{
1625 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb);
1626 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
1627 offsetof(struct rd_msg, opt));
1628 struct ndisc_options ndopts;
1629 SKB_DR(reason);
1630 u8 *hdr;
1631
1632#ifdef CONFIG_IPV6_NDISC_NODETYPE
1633 switch (skb->ndisc_nodetype) {
1634 case NDISC_NODETYPE_HOST:
1635 case NDISC_NODETYPE_NODEFAULT:
1636 ND_PRINTK(2, warn,
1637 "Redirect: from host or unauthorized router\n");
1638 return reason;
1639 }
1640#endif
1641
1642 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1643 ND_PRINTK(2, warn,
1644 "Redirect: source address is not link-local\n");
1645 return reason;
1646 }
1647
1648 if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts))
1649 return SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS;
1650
1651 if (!ndopts.nd_opts_rh) {
1652 ip6_redirect_no_header(skb, dev_net(skb->dev),
1653 skb->dev->ifindex);
1654 return reason;
1655 }
1656
1657 hdr = (u8 *)ndopts.nd_opts_rh;
1658 hdr += 8;
1659 if (!pskb_pull(skb, hdr - skb_transport_header(skb)))
1660 return SKB_DROP_REASON_PKT_TOO_SMALL;
1661
1662 return icmpv6_notify(skb, NDISC_REDIRECT, 0, 0);
1663}
1664
1665static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb,
1666 struct sk_buff *orig_skb,
1667 int rd_len)
1668{
1669 u8 *opt = skb_put(skb, rd_len);
1670
1671 memset(opt, 0, 8);
1672 *(opt++) = ND_OPT_REDIRECT_HDR;
1673 *(opt++) = (rd_len >> 3);
1674 opt += 6;
1675
1676 skb_copy_bits(orig_skb, skb_network_offset(orig_skb), opt,
1677 rd_len - 8);
1678}
1679
1680void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
1681{
1682 struct net_device *dev = skb->dev;
1683 struct net *net = dev_net(dev);
1684 struct sock *sk = net->ipv6.ndisc_sk;
1685 int optlen = 0;
1686 struct inet_peer *peer;
1687 struct sk_buff *buff;
1688 struct rd_msg *msg;
1689 struct in6_addr saddr_buf;
1690 struct rt6_info *rt;
1691 struct dst_entry *dst;
1692 struct flowi6 fl6;
1693 int rd_len;
1694 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL,
1695 ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL;
1696 bool ret;
1697
1698 if (netif_is_l3_master(skb->dev)) {
1699 dev = dev_get_by_index_rcu(dev_net(skb->dev), IPCB(skb)->iif);
1700 if (!dev)
1701 return;
1702 }
1703
1704 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1705 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
1706 dev->name);
1707 return;
1708 }
1709
1710 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1711 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1712 ND_PRINTK(2, warn,
1713 "Redirect: target address is not link-local unicast\n");
1714 return;
1715 }
1716
1717 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1718 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1719
1720 dst = ip6_route_output(net, NULL, &fl6);
1721 if (dst->error) {
1722 dst_release(dst);
1723 return;
1724 }
1725 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1726 if (IS_ERR(dst))
1727 return;
1728
1729 rt = dst_rt6_info(dst);
1730
1731 if (rt->rt6i_flags & RTF_GATEWAY) {
1732 ND_PRINTK(2, warn,
1733 "Redirect: destination is not a neighbour\n");
1734 goto release;
1735 }
1736
1737 rcu_read_lock();
1738 peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr);
1739 ret = inet_peer_xrlim_allow(peer, 1*HZ);
1740 rcu_read_unlock();
1741
1742 if (!ret)
1743 goto release;
1744
1745 if (dev->addr_len) {
1746 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target);
1747 if (!neigh) {
1748 ND_PRINTK(2, warn,
1749 "Redirect: no neigh for target address\n");
1750 goto release;
1751 }
1752
1753 read_lock_bh(&neigh->lock);
1754 if (neigh->nud_state & NUD_VALID) {
1755 memcpy(ha_buf, neigh->ha, dev->addr_len);
1756 read_unlock_bh(&neigh->lock);
1757 ha = ha_buf;
1758 optlen += ndisc_redirect_opt_addr_space(dev, neigh,
1759 ops_data_buf,
1760 &ops_data);
1761 } else
1762 read_unlock_bh(&neigh->lock);
1763
1764 neigh_release(neigh);
1765 }
1766
1767 rd_len = min_t(unsigned int,
1768 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen,
1769 skb->len + 8);
1770 rd_len &= ~0x7;
1771 optlen += rd_len;
1772
1773 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
1774 if (!buff)
1775 goto release;
1776
1777 msg = skb_put(buff, sizeof(*msg));
1778 *msg = (struct rd_msg) {
1779 .icmph = {
1780 .icmp6_type = NDISC_REDIRECT,
1781 },
1782 .target = *target,
1783 .dest = ipv6_hdr(skb)->daddr,
1784 };
1785
1786 /*
1787 * include target_address option
1788 */
1789
1790 if (ha)
1791 ndisc_fill_redirect_addr_option(buff, ha, ops_data);
1792
1793 /*
1794 * build redirect option and copy skb over to the new packet.
1795 */
1796
1797 if (rd_len)
1798 ndisc_fill_redirect_hdr_option(buff, skb, rd_len);
1799
1800 skb_dst_set(buff, dst);
1801 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf);
1802 return;
1803
1804release:
1805 dst_release(dst);
1806}
1807
1808static void pndisc_redo(struct sk_buff *skb)
1809{
1810 enum skb_drop_reason reason = ndisc_recv_ns(skb);
1811
1812 kfree_skb_reason(skb, reason);
1813}
1814
1815static int ndisc_is_multicast(const void *pkey)
1816{
1817 return ipv6_addr_is_multicast((struct in6_addr *)pkey);
1818}
1819
1820static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb)
1821{
1822 struct inet6_dev *idev = __in6_dev_get(skb->dev);
1823
1824 if (!idev)
1825 return true;
1826 if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED &&
1827 READ_ONCE(idev->cnf.suppress_frag_ndisc)) {
1828 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n");
1829 return true;
1830 }
1831 return false;
1832}
1833
1834enum skb_drop_reason ndisc_rcv(struct sk_buff *skb)
1835{
1836 struct nd_msg *msg;
1837 SKB_DR(reason);
1838
1839 if (ndisc_suppress_frag_ndisc(skb))
1840 return SKB_DROP_REASON_IPV6_NDISC_FRAG;
1841
1842 if (skb_linearize(skb))
1843 return SKB_DROP_REASON_NOMEM;
1844
1845 msg = (struct nd_msg *)skb_transport_header(skb);
1846
1847 __skb_push(skb, skb->data - skb_transport_header(skb));
1848
1849 if (ipv6_hdr(skb)->hop_limit != 255) {
1850 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n",
1851 ipv6_hdr(skb)->hop_limit);
1852 return SKB_DROP_REASON_IPV6_NDISC_HOP_LIMIT;
1853 }
1854
1855 if (msg->icmph.icmp6_code != 0) {
1856 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n",
1857 msg->icmph.icmp6_code);
1858 return SKB_DROP_REASON_IPV6_NDISC_BAD_CODE;
1859 }
1860
1861 switch (msg->icmph.icmp6_type) {
1862 case NDISC_NEIGHBOUR_SOLICITATION:
1863 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1864 reason = ndisc_recv_ns(skb);
1865 break;
1866
1867 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1868 reason = ndisc_recv_na(skb);
1869 break;
1870
1871 case NDISC_ROUTER_SOLICITATION:
1872 reason = ndisc_recv_rs(skb);
1873 break;
1874
1875 case NDISC_ROUTER_ADVERTISEMENT:
1876 reason = ndisc_router_discovery(skb);
1877 break;
1878
1879 case NDISC_REDIRECT:
1880 reason = ndisc_redirect_rcv(skb);
1881 break;
1882 }
1883
1884 return reason;
1885}
1886
1887static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1888{
1889 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1890 struct netdev_notifier_change_info *change_info;
1891 struct net *net = dev_net(dev);
1892 struct inet6_dev *idev;
1893 bool evict_nocarrier;
1894
1895 switch (event) {
1896 case NETDEV_CHANGEADDR:
1897 neigh_changeaddr(&nd_tbl, dev);
1898 fib6_run_gc(0, net, false);
1899 fallthrough;
1900 case NETDEV_UP:
1901 idev = in6_dev_get(dev);
1902 if (!idev)
1903 break;
1904 if (READ_ONCE(idev->cnf.ndisc_notify) ||
1905 READ_ONCE(net->ipv6.devconf_all->ndisc_notify))
1906 ndisc_send_unsol_na(dev);
1907 in6_dev_put(idev);
1908 break;
1909 case NETDEV_CHANGE:
1910 idev = in6_dev_get(dev);
1911 if (!idev)
1912 evict_nocarrier = true;
1913 else {
1914 evict_nocarrier = READ_ONCE(idev->cnf.ndisc_evict_nocarrier) &&
1915 READ_ONCE(net->ipv6.devconf_all->ndisc_evict_nocarrier);
1916 in6_dev_put(idev);
1917 }
1918
1919 change_info = ptr;
1920 if (change_info->flags_changed & IFF_NOARP)
1921 neigh_changeaddr(&nd_tbl, dev);
1922 if (evict_nocarrier && !netif_carrier_ok(dev))
1923 neigh_carrier_down(&nd_tbl, dev);
1924 break;
1925 case NETDEV_DOWN:
1926 neigh_ifdown(&nd_tbl, dev);
1927 fib6_run_gc(0, net, false);
1928 break;
1929 case NETDEV_NOTIFY_PEERS:
1930 ndisc_send_unsol_na(dev);
1931 break;
1932 default:
1933 break;
1934 }
1935
1936 return NOTIFY_DONE;
1937}
1938
1939static struct notifier_block ndisc_netdev_notifier = {
1940 .notifier_call = ndisc_netdev_event,
1941 .priority = ADDRCONF_NOTIFY_PRIORITY - 5,
1942};
1943
1944#ifdef CONFIG_SYSCTL
1945static void ndisc_warn_deprecated_sysctl(const struct ctl_table *ctl,
1946 const char *func, const char *dev_name)
1947{
1948 static char warncomm[TASK_COMM_LEN];
1949 static int warned;
1950 if (strcmp(warncomm, current->comm) && warned < 5) {
1951 strscpy(warncomm, current->comm);
1952 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
1953 warncomm, func,
1954 dev_name, ctl->procname,
1955 dev_name, ctl->procname);
1956 warned++;
1957 }
1958}
1959
1960int ndisc_ifinfo_sysctl_change(const struct ctl_table *ctl, int write, void *buffer,
1961 size_t *lenp, loff_t *ppos)
1962{
1963 struct net_device *dev = ctl->extra1;
1964 struct inet6_dev *idev;
1965 int ret;
1966
1967 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1968 (strcmp(ctl->procname, "base_reachable_time") == 0))
1969 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1970
1971 if (strcmp(ctl->procname, "retrans_time") == 0)
1972 ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos);
1973
1974 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1975 ret = neigh_proc_dointvec_jiffies(ctl, write,
1976 buffer, lenp, ppos);
1977
1978 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1979 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1980 ret = neigh_proc_dointvec_ms_jiffies(ctl, write,
1981 buffer, lenp, ppos);
1982 else
1983 ret = -1;
1984
1985 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1986 if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME))
1987 idev->nd_parms->reachable_time =
1988 neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME));
1989 WRITE_ONCE(idev->tstamp, jiffies);
1990 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1991 in6_dev_put(idev);
1992 }
1993 return ret;
1994}
1995
1996
1997#endif
1998
1999static int __net_init ndisc_net_init(struct net *net)
2000{
2001 struct ipv6_pinfo *np;
2002 struct sock *sk;
2003 int err;
2004
2005 err = inet_ctl_sock_create(&sk, PF_INET6,
2006 SOCK_RAW, IPPROTO_ICMPV6, net);
2007 if (err < 0) {
2008 ND_PRINTK(0, err,
2009 "NDISC: Failed to initialize the control socket (err %d)\n",
2010 err);
2011 return err;
2012 }
2013
2014 net->ipv6.ndisc_sk = sk;
2015
2016 np = inet6_sk(sk);
2017 np->hop_limit = 255;
2018 /* Do not loopback ndisc messages */
2019 inet6_clear_bit(MC6_LOOP, sk);
2020
2021 return 0;
2022}
2023
2024static void __net_exit ndisc_net_exit(struct net *net)
2025{
2026 inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
2027}
2028
2029static struct pernet_operations ndisc_net_ops = {
2030 .init = ndisc_net_init,
2031 .exit = ndisc_net_exit,
2032};
2033
2034int __init ndisc_init(void)
2035{
2036 int err;
2037
2038 err = register_pernet_subsys(&ndisc_net_ops);
2039 if (err)
2040 return err;
2041 /*
2042 * Initialize the neighbour table
2043 */
2044 neigh_table_init(NEIGH_ND_TABLE, &nd_tbl);
2045
2046#ifdef CONFIG_SYSCTL
2047 err = neigh_sysctl_register(NULL, &nd_tbl.parms,
2048 ndisc_ifinfo_sysctl_change);
2049 if (err)
2050 goto out_unregister_pernet;
2051out:
2052#endif
2053 return err;
2054
2055#ifdef CONFIG_SYSCTL
2056out_unregister_pernet:
2057 unregister_pernet_subsys(&ndisc_net_ops);
2058 goto out;
2059#endif
2060}
2061
2062int __init ndisc_late_init(void)
2063{
2064 return register_netdevice_notifier(&ndisc_netdev_notifier);
2065}
2066
2067void ndisc_late_cleanup(void)
2068{
2069 unregister_netdevice_notifier(&ndisc_netdev_notifier);
2070}
2071
2072void ndisc_cleanup(void)
2073{
2074#ifdef CONFIG_SYSCTL
2075 neigh_sysctl_unregister(&nd_tbl.parms);
2076#endif
2077 neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl);
2078 unregister_pernet_subsys(&ndisc_net_ops);
2079}
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_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/* Set to 3 to get tracing... */
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
146/* ND options */
147struct ndisc_options {
148 struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
149#ifdef CONFIG_IPV6_ROUTE_INFO
150 struct nd_opt_hdr *nd_opts_ri;
151 struct nd_opt_hdr *nd_opts_ri_end;
152#endif
153 struct nd_opt_hdr *nd_useropts;
154 struct nd_opt_hdr *nd_useropts_end;
155};
156
157#define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
158#define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
159#define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
160#define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END]
161#define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
162#define nd_opts_mtu nd_opt_array[ND_OPT_MTU]
163
164#define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
165
166/*
167 * Return the padding between the option length and the start of the
168 * link addr. Currently only IP-over-InfiniBand needs this, although
169 * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
170 * also need a pad of 2.
171 */
172static int ndisc_addr_option_pad(unsigned short type)
173{
174 switch (type) {
175 case ARPHRD_INFINIBAND: return 2;
176 default: return 0;
177 }
178}
179
180static inline int ndisc_opt_addr_space(struct net_device *dev)
181{
182 return NDISC_OPT_SPACE(dev->addr_len + ndisc_addr_option_pad(dev->type));
183}
184
185static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len,
186 unsigned short addr_type)
187{
188 int space = NDISC_OPT_SPACE(data_len);
189 int pad = ndisc_addr_option_pad(addr_type);
190
191 opt[0] = type;
192 opt[1] = space>>3;
193
194 memset(opt + 2, 0, pad);
195 opt += pad;
196 space -= pad;
197
198 memcpy(opt+2, data, data_len);
199 data_len += 2;
200 opt += data_len;
201 if ((space -= data_len) > 0)
202 memset(opt, 0, space);
203 return opt + space;
204}
205
206static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
207 struct nd_opt_hdr *end)
208{
209 int type;
210 if (!cur || !end || cur >= end)
211 return NULL;
212 type = cur->nd_opt_type;
213 do {
214 cur = ((void *)cur) + (cur->nd_opt_len << 3);
215 } while(cur < end && cur->nd_opt_type != type);
216 return cur <= end && cur->nd_opt_type == type ? cur : NULL;
217}
218
219static inline int ndisc_is_useropt(struct nd_opt_hdr *opt)
220{
221 return opt->nd_opt_type == ND_OPT_RDNSS ||
222 opt->nd_opt_type == ND_OPT_DNSSL;
223}
224
225static struct nd_opt_hdr *ndisc_next_useropt(struct nd_opt_hdr *cur,
226 struct nd_opt_hdr *end)
227{
228 if (!cur || !end || cur >= end)
229 return NULL;
230 do {
231 cur = ((void *)cur) + (cur->nd_opt_len << 3);
232 } while(cur < end && !ndisc_is_useropt(cur));
233 return cur <= end && ndisc_is_useropt(cur) ? cur : NULL;
234}
235
236static struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
237 struct ndisc_options *ndopts)
238{
239 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
240
241 if (!nd_opt || opt_len < 0 || !ndopts)
242 return NULL;
243 memset(ndopts, 0, sizeof(*ndopts));
244 while (opt_len) {
245 int l;
246 if (opt_len < sizeof(struct nd_opt_hdr))
247 return NULL;
248 l = nd_opt->nd_opt_len << 3;
249 if (opt_len < l || l == 0)
250 return NULL;
251 switch (nd_opt->nd_opt_type) {
252 case ND_OPT_SOURCE_LL_ADDR:
253 case ND_OPT_TARGET_LL_ADDR:
254 case ND_OPT_MTU:
255 case ND_OPT_REDIRECT_HDR:
256 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
257 ND_PRINTK(2, warn,
258 "%s: duplicated ND6 option found: type=%d\n",
259 __func__, nd_opt->nd_opt_type);
260 } else {
261 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
262 }
263 break;
264 case ND_OPT_PREFIX_INFO:
265 ndopts->nd_opts_pi_end = nd_opt;
266 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
267 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
268 break;
269#ifdef CONFIG_IPV6_ROUTE_INFO
270 case ND_OPT_ROUTE_INFO:
271 ndopts->nd_opts_ri_end = nd_opt;
272 if (!ndopts->nd_opts_ri)
273 ndopts->nd_opts_ri = nd_opt;
274 break;
275#endif
276 default:
277 if (ndisc_is_useropt(nd_opt)) {
278 ndopts->nd_useropts_end = nd_opt;
279 if (!ndopts->nd_useropts)
280 ndopts->nd_useropts = nd_opt;
281 } else {
282 /*
283 * Unknown options must be silently ignored,
284 * to accommodate future extension to the
285 * protocol.
286 */
287 ND_PRINTK(2, notice,
288 "%s: ignored unsupported option; type=%d, len=%d\n",
289 __func__,
290 nd_opt->nd_opt_type,
291 nd_opt->nd_opt_len);
292 }
293 }
294 opt_len -= l;
295 nd_opt = ((void *)nd_opt) + l;
296 }
297 return ndopts;
298}
299
300static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
301 struct net_device *dev)
302{
303 u8 *lladdr = (u8 *)(p + 1);
304 int lladdrlen = p->nd_opt_len << 3;
305 int prepad = ndisc_addr_option_pad(dev->type);
306 if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad))
307 return NULL;
308 return lladdr + prepad;
309}
310
311int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
312{
313 switch (dev->type) {
314 case ARPHRD_ETHER:
315 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
316 case ARPHRD_FDDI:
317 ipv6_eth_mc_map(addr, buf);
318 return 0;
319 case ARPHRD_ARCNET:
320 ipv6_arcnet_mc_map(addr, buf);
321 return 0;
322 case ARPHRD_INFINIBAND:
323 ipv6_ib_mc_map(addr, dev->broadcast, buf);
324 return 0;
325 case ARPHRD_IPGRE:
326 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
327 default:
328 if (dir) {
329 memcpy(buf, dev->broadcast, dev->addr_len);
330 return 0;
331 }
332 }
333 return -EINVAL;
334}
335
336EXPORT_SYMBOL(ndisc_mc_map);
337
338static u32 ndisc_hash(const void *pkey,
339 const struct net_device *dev,
340 __u32 *hash_rnd)
341{
342 return ndisc_hashfn(pkey, dev, hash_rnd);
343}
344
345static int ndisc_constructor(struct neighbour *neigh)
346{
347 struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key;
348 struct net_device *dev = neigh->dev;
349 struct inet6_dev *in6_dev;
350 struct neigh_parms *parms;
351 bool is_multicast = ipv6_addr_is_multicast(addr);
352
353 in6_dev = in6_dev_get(dev);
354 if (in6_dev == NULL) {
355 return -EINVAL;
356 }
357
358 parms = in6_dev->nd_parms;
359 __neigh_parms_put(neigh->parms);
360 neigh->parms = neigh_parms_clone(parms);
361
362 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
363 if (!dev->header_ops) {
364 neigh->nud_state = NUD_NOARP;
365 neigh->ops = &ndisc_direct_ops;
366 neigh->output = neigh_direct_output;
367 } else {
368 if (is_multicast) {
369 neigh->nud_state = NUD_NOARP;
370 ndisc_mc_map(addr, neigh->ha, dev, 1);
371 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
372 neigh->nud_state = NUD_NOARP;
373 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
374 if (dev->flags&IFF_LOOPBACK)
375 neigh->type = RTN_LOCAL;
376 } else if (dev->flags&IFF_POINTOPOINT) {
377 neigh->nud_state = NUD_NOARP;
378 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
379 }
380 if (dev->header_ops->cache)
381 neigh->ops = &ndisc_hh_ops;
382 else
383 neigh->ops = &ndisc_generic_ops;
384 if (neigh->nud_state&NUD_VALID)
385 neigh->output = neigh->ops->connected_output;
386 else
387 neigh->output = neigh->ops->output;
388 }
389 in6_dev_put(in6_dev);
390 return 0;
391}
392
393static int pndisc_constructor(struct pneigh_entry *n)
394{
395 struct in6_addr *addr = (struct in6_addr*)&n->key;
396 struct in6_addr maddr;
397 struct net_device *dev = n->dev;
398
399 if (dev == NULL || __in6_dev_get(dev) == NULL)
400 return -EINVAL;
401 addrconf_addr_solict_mult(addr, &maddr);
402 ipv6_dev_mc_inc(dev, &maddr);
403 return 0;
404}
405
406static void pndisc_destructor(struct pneigh_entry *n)
407{
408 struct in6_addr *addr = (struct in6_addr*)&n->key;
409 struct in6_addr maddr;
410 struct net_device *dev = n->dev;
411
412 if (dev == NULL || __in6_dev_get(dev) == NULL)
413 return;
414 addrconf_addr_solict_mult(addr, &maddr);
415 ipv6_dev_mc_dec(dev, &maddr);
416}
417
418struct sk_buff *ndisc_build_skb(struct net_device *dev,
419 const struct in6_addr *daddr,
420 const struct in6_addr *saddr,
421 struct icmp6hdr *icmp6h,
422 const struct in6_addr *target,
423 int llinfo)
424{
425 struct net *net = dev_net(dev);
426 struct sock *sk = net->ipv6.ndisc_sk;
427 struct sk_buff *skb;
428 struct icmp6hdr *hdr;
429 int hlen = LL_RESERVED_SPACE(dev);
430 int tlen = dev->needed_tailroom;
431 int len;
432 int err;
433 u8 *opt;
434
435 if (!dev->addr_len)
436 llinfo = 0;
437
438 len = sizeof(struct icmp6hdr) + (target ? sizeof(*target) : 0);
439 if (llinfo)
440 len += ndisc_opt_addr_space(dev);
441
442 skb = sock_alloc_send_skb(sk,
443 (MAX_HEADER + sizeof(struct ipv6hdr) +
444 len + hlen + tlen),
445 1, &err);
446 if (!skb) {
447 ND_PRINTK(0, err, "ND: %s failed to allocate an skb, err=%d\n",
448 __func__, err);
449 return NULL;
450 }
451
452 skb_reserve(skb, hlen);
453 ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
454
455 skb->transport_header = skb->tail;
456 skb_put(skb, len);
457
458 hdr = (struct icmp6hdr *)skb_transport_header(skb);
459 memcpy(hdr, icmp6h, sizeof(*hdr));
460
461 opt = skb_transport_header(skb) + sizeof(struct icmp6hdr);
462 if (target) {
463 *(struct in6_addr *)opt = *target;
464 opt += sizeof(*target);
465 }
466
467 if (llinfo)
468 ndisc_fill_addr_option(opt, llinfo, dev->dev_addr,
469 dev->addr_len, dev->type);
470
471 hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len,
472 IPPROTO_ICMPV6,
473 csum_partial(hdr,
474 len, 0));
475
476 return skb;
477}
478
479EXPORT_SYMBOL(ndisc_build_skb);
480
481void ndisc_send_skb(struct sk_buff *skb,
482 struct net_device *dev,
483 struct neighbour *neigh,
484 const struct in6_addr *daddr,
485 const struct in6_addr *saddr,
486 struct icmp6hdr *icmp6h)
487{
488 struct flowi6 fl6;
489 struct dst_entry *dst;
490 struct net *net = dev_net(dev);
491 struct sock *sk = net->ipv6.ndisc_sk;
492 struct inet6_dev *idev;
493 int err;
494 u8 type;
495
496 type = icmp6h->icmp6_type;
497
498 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, dev->ifindex);
499 dst = icmp6_dst_alloc(dev, neigh, &fl6);
500 if (IS_ERR(dst)) {
501 kfree_skb(skb);
502 return;
503 }
504
505 skb_dst_set(skb, dst);
506
507 rcu_read_lock();
508 idev = __in6_dev_get(dst->dev);
509 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
510
511 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev,
512 dst_output);
513 if (!err) {
514 ICMP6MSGOUT_INC_STATS(net, idev, type);
515 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
516 }
517
518 rcu_read_unlock();
519}
520
521EXPORT_SYMBOL(ndisc_send_skb);
522
523/*
524 * Send a Neighbour Discover packet
525 */
526static void __ndisc_send(struct net_device *dev,
527 struct neighbour *neigh,
528 const struct in6_addr *daddr,
529 const struct in6_addr *saddr,
530 struct icmp6hdr *icmp6h, const struct in6_addr *target,
531 int llinfo)
532{
533 struct sk_buff *skb;
534
535 skb = ndisc_build_skb(dev, daddr, saddr, icmp6h, target, llinfo);
536 if (!skb)
537 return;
538
539 ndisc_send_skb(skb, dev, neigh, daddr, saddr, icmp6h);
540}
541
542static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
543 const struct in6_addr *daddr,
544 const struct in6_addr *solicited_addr,
545 int router, int solicited, int override, int inc_opt)
546{
547 struct in6_addr tmpaddr;
548 struct inet6_ifaddr *ifp;
549 const struct in6_addr *src_addr;
550 struct icmp6hdr icmp6h = {
551 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
552 };
553
554 /* for anycast or proxy, solicited_addr != src_addr */
555 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
556 if (ifp) {
557 src_addr = solicited_addr;
558 if (ifp->flags & IFA_F_OPTIMISTIC)
559 override = 0;
560 inc_opt |= ifp->idev->cnf.force_tllao;
561 in6_ifa_put(ifp);
562 } else {
563 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
564 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
565 &tmpaddr))
566 return;
567 src_addr = &tmpaddr;
568 }
569
570 icmp6h.icmp6_router = router;
571 icmp6h.icmp6_solicited = solicited;
572 icmp6h.icmp6_override = override;
573
574 __ndisc_send(dev, neigh, daddr, src_addr,
575 &icmp6h, solicited_addr,
576 inc_opt ? ND_OPT_TARGET_LL_ADDR : 0);
577}
578
579static void ndisc_send_unsol_na(struct net_device *dev)
580{
581 struct inet6_dev *idev;
582 struct inet6_ifaddr *ifa;
583 struct in6_addr mcaddr;
584
585 idev = in6_dev_get(dev);
586 if (!idev)
587 return;
588
589 read_lock_bh(&idev->lock);
590 list_for_each_entry(ifa, &idev->addr_list, if_list) {
591 addrconf_addr_solict_mult(&ifa->addr, &mcaddr);
592 ndisc_send_na(dev, NULL, &mcaddr, &ifa->addr,
593 /*router=*/ !!idev->cnf.forwarding,
594 /*solicited=*/ false, /*override=*/ true,
595 /*inc_opt=*/ true);
596 }
597 read_unlock_bh(&idev->lock);
598
599 in6_dev_put(idev);
600}
601
602void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
603 const struct in6_addr *solicit,
604 const struct in6_addr *daddr, const struct in6_addr *saddr)
605{
606 struct in6_addr addr_buf;
607 struct icmp6hdr icmp6h = {
608 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
609 };
610
611 if (saddr == NULL) {
612 if (ipv6_get_lladdr(dev, &addr_buf,
613 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
614 return;
615 saddr = &addr_buf;
616 }
617
618 __ndisc_send(dev, neigh, daddr, saddr,
619 &icmp6h, solicit,
620 !ipv6_addr_any(saddr) ? ND_OPT_SOURCE_LL_ADDR : 0);
621}
622
623void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
624 const struct in6_addr *daddr)
625{
626 struct icmp6hdr icmp6h = {
627 .icmp6_type = NDISC_ROUTER_SOLICITATION,
628 };
629 int send_sllao = dev->addr_len;
630
631#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
632 /*
633 * According to section 2.2 of RFC 4429, we must not
634 * send router solicitations with a sllao from
635 * optimistic addresses, but we may send the solicitation
636 * if we don't include the sllao. So here we check
637 * if our address is optimistic, and if so, we
638 * suppress the inclusion of the sllao.
639 */
640 if (send_sllao) {
641 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
642 dev, 1);
643 if (ifp) {
644 if (ifp->flags & IFA_F_OPTIMISTIC) {
645 send_sllao = 0;
646 }
647 in6_ifa_put(ifp);
648 } else {
649 send_sllao = 0;
650 }
651 }
652#endif
653 __ndisc_send(dev, NULL, daddr, saddr,
654 &icmp6h, NULL,
655 send_sllao ? ND_OPT_SOURCE_LL_ADDR : 0);
656}
657
658
659static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
660{
661 /*
662 * "The sender MUST return an ICMP
663 * destination unreachable"
664 */
665 dst_link_failure(skb);
666 kfree_skb(skb);
667}
668
669/* Called with locked neigh: either read or both */
670
671static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
672{
673 struct in6_addr *saddr = NULL;
674 struct in6_addr mcaddr;
675 struct net_device *dev = neigh->dev;
676 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
677 int probes = atomic_read(&neigh->probes);
678
679 if (skb && ipv6_chk_addr(dev_net(dev), &ipv6_hdr(skb)->saddr, dev, 1))
680 saddr = &ipv6_hdr(skb)->saddr;
681
682 if ((probes -= neigh->parms->ucast_probes) < 0) {
683 if (!(neigh->nud_state & NUD_VALID)) {
684 ND_PRINTK(1, dbg,
685 "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
686 __func__, target);
687 }
688 ndisc_send_ns(dev, neigh, target, target, saddr);
689 } else if ((probes -= neigh->parms->app_probes) < 0) {
690#ifdef CONFIG_ARPD
691 neigh_app_ns(neigh);
692#endif
693 } else {
694 addrconf_addr_solict_mult(target, &mcaddr);
695 ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
696 }
697}
698
699static int pndisc_is_router(const void *pkey,
700 struct net_device *dev)
701{
702 struct pneigh_entry *n;
703 int ret = -1;
704
705 read_lock_bh(&nd_tbl.lock);
706 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
707 if (n)
708 ret = !!(n->flags & NTF_ROUTER);
709 read_unlock_bh(&nd_tbl.lock);
710
711 return ret;
712}
713
714static void ndisc_recv_ns(struct sk_buff *skb)
715{
716 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
717 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
718 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
719 u8 *lladdr = NULL;
720 u32 ndoptlen = skb->tail - (skb->transport_header +
721 offsetof(struct nd_msg, opt));
722 struct ndisc_options ndopts;
723 struct net_device *dev = skb->dev;
724 struct inet6_ifaddr *ifp;
725 struct inet6_dev *idev = NULL;
726 struct neighbour *neigh;
727 int dad = ipv6_addr_any(saddr);
728 bool inc;
729 int is_router = -1;
730
731 if (ipv6_addr_is_multicast(&msg->target)) {
732 ND_PRINTK(2, warn, "NS: multicast target address\n");
733 return;
734 }
735
736 /*
737 * RFC2461 7.1.1:
738 * DAD has to be destined for solicited node multicast address.
739 */
740 if (dad &&
741 !(daddr->s6_addr32[0] == htonl(0xff020000) &&
742 daddr->s6_addr32[1] == htonl(0x00000000) &&
743 daddr->s6_addr32[2] == htonl(0x00000001) &&
744 daddr->s6_addr [12] == 0xff )) {
745 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n");
746 return;
747 }
748
749 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
750 ND_PRINTK(2, warn, "NS: invalid ND options\n");
751 return;
752 }
753
754 if (ndopts.nd_opts_src_lladdr) {
755 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
756 if (!lladdr) {
757 ND_PRINTK(2, warn,
758 "NS: invalid link-layer address length\n");
759 return;
760 }
761
762 /* RFC2461 7.1.1:
763 * If the IP source address is the unspecified address,
764 * there MUST NOT be source link-layer address option
765 * in the message.
766 */
767 if (dad) {
768 ND_PRINTK(2, warn,
769 "NS: bad DAD packet (link-layer address option)\n");
770 return;
771 }
772 }
773
774 inc = ipv6_addr_is_multicast(daddr);
775
776 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
777 if (ifp) {
778
779 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
780 if (dad) {
781 /*
782 * We are colliding with another node
783 * who is doing DAD
784 * so fail our DAD process
785 */
786 addrconf_dad_failure(ifp);
787 return;
788 } else {
789 /*
790 * This is not a dad solicitation.
791 * If we are an optimistic node,
792 * we should respond.
793 * Otherwise, we should ignore it.
794 */
795 if (!(ifp->flags & IFA_F_OPTIMISTIC))
796 goto out;
797 }
798 }
799
800 idev = ifp->idev;
801 } else {
802 struct net *net = dev_net(dev);
803
804 idev = in6_dev_get(dev);
805 if (!idev) {
806 /* XXX: count this drop? */
807 return;
808 }
809
810 if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
811 (idev->cnf.forwarding &&
812 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
813 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
814 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
815 skb->pkt_type != PACKET_HOST &&
816 inc != 0 &&
817 idev->nd_parms->proxy_delay != 0) {
818 /*
819 * for anycast or proxy,
820 * sender should delay its response
821 * by a random time between 0 and
822 * MAX_ANYCAST_DELAY_TIME seconds.
823 * (RFC2461) -- yoshfuji
824 */
825 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
826 if (n)
827 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
828 goto out;
829 }
830 } else
831 goto out;
832 }
833
834 if (is_router < 0)
835 is_router = !!idev->cnf.forwarding;
836
837 if (dad) {
838 ndisc_send_na(dev, NULL, &in6addr_linklocal_allnodes, &msg->target,
839 is_router, 0, (ifp != NULL), 1);
840 goto out;
841 }
842
843 if (inc)
844 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
845 else
846 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
847
848 /*
849 * update / create cache entry
850 * for the source address
851 */
852 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
853 !inc || lladdr || !dev->addr_len);
854 if (neigh)
855 neigh_update(neigh, lladdr, NUD_STALE,
856 NEIGH_UPDATE_F_WEAK_OVERRIDE|
857 NEIGH_UPDATE_F_OVERRIDE);
858 if (neigh || !dev->header_ops) {
859 ndisc_send_na(dev, neigh, saddr, &msg->target,
860 is_router,
861 1, (ifp != NULL && inc), inc);
862 if (neigh)
863 neigh_release(neigh);
864 }
865
866out:
867 if (ifp)
868 in6_ifa_put(ifp);
869 else
870 in6_dev_put(idev);
871}
872
873static void ndisc_recv_na(struct sk_buff *skb)
874{
875 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
876 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
877 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
878 u8 *lladdr = NULL;
879 u32 ndoptlen = skb->tail - (skb->transport_header +
880 offsetof(struct nd_msg, opt));
881 struct ndisc_options ndopts;
882 struct net_device *dev = skb->dev;
883 struct inet6_ifaddr *ifp;
884 struct neighbour *neigh;
885
886 if (skb->len < sizeof(struct nd_msg)) {
887 ND_PRINTK(2, warn, "NA: packet too short\n");
888 return;
889 }
890
891 if (ipv6_addr_is_multicast(&msg->target)) {
892 ND_PRINTK(2, warn, "NA: target address is multicast\n");
893 return;
894 }
895
896 if (ipv6_addr_is_multicast(daddr) &&
897 msg->icmph.icmp6_solicited) {
898 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n");
899 return;
900 }
901
902 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
903 ND_PRINTK(2, warn, "NS: invalid ND option\n");
904 return;
905 }
906 if (ndopts.nd_opts_tgt_lladdr) {
907 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
908 if (!lladdr) {
909 ND_PRINTK(2, warn,
910 "NA: invalid link-layer address length\n");
911 return;
912 }
913 }
914 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
915 if (ifp) {
916 if (skb->pkt_type != PACKET_LOOPBACK
917 && (ifp->flags & IFA_F_TENTATIVE)) {
918 addrconf_dad_failure(ifp);
919 return;
920 }
921 /* What should we make now? The advertisement
922 is invalid, but ndisc specs say nothing
923 about it. It could be misconfiguration, or
924 an smart proxy agent tries to help us :-)
925
926 We should not print the error if NA has been
927 received from loopback - it is just our own
928 unsolicited advertisement.
929 */
930 if (skb->pkt_type != PACKET_LOOPBACK)
931 ND_PRINTK(1, warn,
932 "NA: someone advertises our address %pI6 on %s!\n",
933 &ifp->addr, ifp->idev->dev->name);
934 in6_ifa_put(ifp);
935 return;
936 }
937 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
938
939 if (neigh) {
940 u8 old_flags = neigh->flags;
941 struct net *net = dev_net(dev);
942
943 if (neigh->nud_state & NUD_FAILED)
944 goto out;
945
946 /*
947 * Don't update the neighbor cache entry on a proxy NA from
948 * ourselves because either the proxied node is off link or it
949 * has already sent a NA to us.
950 */
951 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
952 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
953 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
954 /* XXX: idev->cnf.prixy_ndp */
955 goto out;
956 }
957
958 neigh_update(neigh, lladdr,
959 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
960 NEIGH_UPDATE_F_WEAK_OVERRIDE|
961 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
962 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
963 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
964
965 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
966 /*
967 * Change: router to host
968 */
969 struct rt6_info *rt;
970 rt = rt6_get_dflt_router(saddr, dev);
971 if (rt)
972 ip6_del_rt(rt);
973 }
974
975out:
976 neigh_release(neigh);
977 }
978}
979
980static void ndisc_recv_rs(struct sk_buff *skb)
981{
982 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
983 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
984 struct neighbour *neigh;
985 struct inet6_dev *idev;
986 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
987 struct ndisc_options ndopts;
988 u8 *lladdr = NULL;
989
990 if (skb->len < sizeof(*rs_msg))
991 return;
992
993 idev = __in6_dev_get(skb->dev);
994 if (!idev) {
995 ND_PRINTK(1, err, "RS: can't find in6 device\n");
996 return;
997 }
998
999 /* Don't accept RS if we're not in router mode */
1000 if (!idev->cnf.forwarding)
1001 goto out;
1002
1003 /*
1004 * Don't update NCE if src = ::;
1005 * this implies that the source node has no ip address assigned yet.
1006 */
1007 if (ipv6_addr_any(saddr))
1008 goto out;
1009
1010 /* Parse ND options */
1011 if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
1012 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n");
1013 goto out;
1014 }
1015
1016 if (ndopts.nd_opts_src_lladdr) {
1017 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1018 skb->dev);
1019 if (!lladdr)
1020 goto out;
1021 }
1022
1023 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1024 if (neigh) {
1025 neigh_update(neigh, lladdr, NUD_STALE,
1026 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1027 NEIGH_UPDATE_F_OVERRIDE|
1028 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1029 neigh_release(neigh);
1030 }
1031out:
1032 return;
1033}
1034
1035static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1036{
1037 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1038 struct sk_buff *skb;
1039 struct nlmsghdr *nlh;
1040 struct nduseroptmsg *ndmsg;
1041 struct net *net = dev_net(ra->dev);
1042 int err;
1043 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1044 + (opt->nd_opt_len << 3));
1045 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1046
1047 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1048 if (skb == NULL) {
1049 err = -ENOBUFS;
1050 goto errout;
1051 }
1052
1053 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1054 if (nlh == NULL) {
1055 goto nla_put_failure;
1056 }
1057
1058 ndmsg = nlmsg_data(nlh);
1059 ndmsg->nduseropt_family = AF_INET6;
1060 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1061 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1062 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1063 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1064
1065 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1066
1067 if (nla_put(skb, NDUSEROPT_SRCADDR, sizeof(struct in6_addr),
1068 &ipv6_hdr(ra)->saddr))
1069 goto nla_put_failure;
1070 nlmsg_end(skb, nlh);
1071
1072 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1073 return;
1074
1075nla_put_failure:
1076 nlmsg_free(skb);
1077 err = -EMSGSIZE;
1078errout:
1079 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1080}
1081
1082static inline int accept_ra(struct inet6_dev *in6_dev)
1083{
1084 /*
1085 * If forwarding is enabled, RA are not accepted unless the special
1086 * hybrid mode (accept_ra=2) is enabled.
1087 */
1088 if (in6_dev->cnf.forwarding && in6_dev->cnf.accept_ra < 2)
1089 return 0;
1090
1091 return in6_dev->cnf.accept_ra;
1092}
1093
1094static void ndisc_router_discovery(struct sk_buff *skb)
1095{
1096 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1097 struct neighbour *neigh = NULL;
1098 struct inet6_dev *in6_dev;
1099 struct rt6_info *rt = NULL;
1100 int lifetime;
1101 struct ndisc_options ndopts;
1102 int optlen;
1103 unsigned int pref = 0;
1104
1105 __u8 * opt = (__u8 *)(ra_msg + 1);
1106
1107 optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg);
1108
1109 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1110 ND_PRINTK(2, warn, "RA: source address is not link-local\n");
1111 return;
1112 }
1113 if (optlen < 0) {
1114 ND_PRINTK(2, warn, "RA: packet too short\n");
1115 return;
1116 }
1117
1118#ifdef CONFIG_IPV6_NDISC_NODETYPE
1119 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1120 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n");
1121 return;
1122 }
1123#endif
1124
1125 /*
1126 * set the RA_RECV flag in the interface
1127 */
1128
1129 in6_dev = __in6_dev_get(skb->dev);
1130 if (in6_dev == NULL) {
1131 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n",
1132 skb->dev->name);
1133 return;
1134 }
1135
1136 if (!ndisc_parse_options(opt, optlen, &ndopts)) {
1137 ND_PRINTK(2, warn, "RA: invalid ND options\n");
1138 return;
1139 }
1140
1141 if (!accept_ra(in6_dev))
1142 goto skip_linkparms;
1143
1144#ifdef CONFIG_IPV6_NDISC_NODETYPE
1145 /* skip link-specific parameters from interior routers */
1146 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT)
1147 goto skip_linkparms;
1148#endif
1149
1150 if (in6_dev->if_flags & IF_RS_SENT) {
1151 /*
1152 * flag that an RA was received after an RS was sent
1153 * out on this interface.
1154 */
1155 in6_dev->if_flags |= IF_RA_RCVD;
1156 }
1157
1158 /*
1159 * Remember the managed/otherconf flags from most recently
1160 * received RA message (RFC 2462) -- yoshfuji
1161 */
1162 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1163 IF_RA_OTHERCONF)) |
1164 (ra_msg->icmph.icmp6_addrconf_managed ?
1165 IF_RA_MANAGED : 0) |
1166 (ra_msg->icmph.icmp6_addrconf_other ?
1167 IF_RA_OTHERCONF : 0);
1168
1169 if (!in6_dev->cnf.accept_ra_defrtr)
1170 goto skip_defrtr;
1171
1172 if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0))
1173 goto skip_defrtr;
1174
1175 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1176
1177#ifdef CONFIG_IPV6_ROUTER_PREF
1178 pref = ra_msg->icmph.icmp6_router_pref;
1179 /* 10b is handled as if it were 00b (medium) */
1180 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1181 !in6_dev->cnf.accept_ra_rtr_pref)
1182 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1183#endif
1184
1185 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1186
1187 if (rt) {
1188 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1189 if (!neigh) {
1190 ND_PRINTK(0, err,
1191 "RA: %s got default router without neighbour\n",
1192 __func__);
1193 dst_release(&rt->dst);
1194 return;
1195 }
1196 }
1197 if (rt && lifetime == 0) {
1198 ip6_del_rt(rt);
1199 rt = NULL;
1200 }
1201
1202 if (rt == NULL && lifetime) {
1203 ND_PRINTK(3, dbg, "RA: adding default router\n");
1204
1205 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1206 if (rt == NULL) {
1207 ND_PRINTK(0, err,
1208 "RA: %s failed to add default route\n",
1209 __func__);
1210 return;
1211 }
1212
1213 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1214 if (neigh == NULL) {
1215 ND_PRINTK(0, err,
1216 "RA: %s got default router without neighbour\n",
1217 __func__);
1218 dst_release(&rt->dst);
1219 return;
1220 }
1221 neigh->flags |= NTF_ROUTER;
1222 } else if (rt) {
1223 rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1224 }
1225
1226 if (rt)
1227 rt6_set_expires(rt, jiffies + (HZ * lifetime));
1228 if (ra_msg->icmph.icmp6_hop_limit) {
1229 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1230 if (rt)
1231 dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
1232 ra_msg->icmph.icmp6_hop_limit);
1233 }
1234
1235skip_defrtr:
1236
1237 /*
1238 * Update Reachable Time and Retrans Timer
1239 */
1240
1241 if (in6_dev->nd_parms) {
1242 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1243
1244 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1245 rtime = (rtime*HZ)/1000;
1246 if (rtime < HZ/10)
1247 rtime = HZ/10;
1248 in6_dev->nd_parms->retrans_time = rtime;
1249 in6_dev->tstamp = jiffies;
1250 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1251 }
1252
1253 rtime = ntohl(ra_msg->reachable_time);
1254 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1255 rtime = (rtime*HZ)/1000;
1256
1257 if (rtime < HZ/10)
1258 rtime = HZ/10;
1259
1260 if (rtime != in6_dev->nd_parms->base_reachable_time) {
1261 in6_dev->nd_parms->base_reachable_time = rtime;
1262 in6_dev->nd_parms->gc_staletime = 3 * rtime;
1263 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1264 in6_dev->tstamp = jiffies;
1265 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1266 }
1267 }
1268 }
1269
1270skip_linkparms:
1271
1272 /*
1273 * Process options.
1274 */
1275
1276 if (!neigh)
1277 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1278 skb->dev, 1);
1279 if (neigh) {
1280 u8 *lladdr = NULL;
1281 if (ndopts.nd_opts_src_lladdr) {
1282 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1283 skb->dev);
1284 if (!lladdr) {
1285 ND_PRINTK(2, warn,
1286 "RA: invalid link-layer address length\n");
1287 goto out;
1288 }
1289 }
1290 neigh_update(neigh, lladdr, NUD_STALE,
1291 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1292 NEIGH_UPDATE_F_OVERRIDE|
1293 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1294 NEIGH_UPDATE_F_ISROUTER);
1295 }
1296
1297 if (!accept_ra(in6_dev))
1298 goto out;
1299
1300#ifdef CONFIG_IPV6_ROUTE_INFO
1301 if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0))
1302 goto skip_routeinfo;
1303
1304 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1305 struct nd_opt_hdr *p;
1306 for (p = ndopts.nd_opts_ri;
1307 p;
1308 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1309 struct route_info *ri = (struct route_info *)p;
1310#ifdef CONFIG_IPV6_NDISC_NODETYPE
1311 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1312 ri->prefix_len == 0)
1313 continue;
1314#endif
1315 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1316 continue;
1317 rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3,
1318 &ipv6_hdr(skb)->saddr);
1319 }
1320 }
1321
1322skip_routeinfo:
1323#endif
1324
1325#ifdef CONFIG_IPV6_NDISC_NODETYPE
1326 /* skip link-specific ndopts from interior routers */
1327 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT)
1328 goto out;
1329#endif
1330
1331 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1332 struct nd_opt_hdr *p;
1333 for (p = ndopts.nd_opts_pi;
1334 p;
1335 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1336 addrconf_prefix_rcv(skb->dev, (u8 *)p,
1337 (p->nd_opt_len) << 3,
1338 ndopts.nd_opts_src_lladdr != NULL);
1339 }
1340 }
1341
1342 if (ndopts.nd_opts_mtu) {
1343 __be32 n;
1344 u32 mtu;
1345
1346 memcpy(&n, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1347 mtu = ntohl(n);
1348
1349 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1350 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu);
1351 } else if (in6_dev->cnf.mtu6 != mtu) {
1352 in6_dev->cnf.mtu6 = mtu;
1353
1354 if (rt)
1355 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
1356
1357 rt6_mtu_change(skb->dev, mtu);
1358 }
1359 }
1360
1361 if (ndopts.nd_useropts) {
1362 struct nd_opt_hdr *p;
1363 for (p = ndopts.nd_useropts;
1364 p;
1365 p = ndisc_next_useropt(p, ndopts.nd_useropts_end)) {
1366 ndisc_ra_useropt(skb, p);
1367 }
1368 }
1369
1370 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1371 ND_PRINTK(2, warn, "RA: invalid RA options\n");
1372 }
1373out:
1374 if (rt)
1375 dst_release(&rt->dst);
1376 if (neigh)
1377 neigh_release(neigh);
1378}
1379
1380static void ndisc_redirect_rcv(struct sk_buff *skb)
1381{
1382 struct inet6_dev *in6_dev;
1383 struct icmp6hdr *icmph;
1384 const struct in6_addr *dest;
1385 const struct in6_addr *target; /* new first hop to destination */
1386 struct neighbour *neigh;
1387 int on_link = 0;
1388 struct ndisc_options ndopts;
1389 int optlen;
1390 u8 *lladdr = NULL;
1391
1392#ifdef CONFIG_IPV6_NDISC_NODETYPE
1393 switch (skb->ndisc_nodetype) {
1394 case NDISC_NODETYPE_HOST:
1395 case NDISC_NODETYPE_NODEFAULT:
1396 ND_PRINTK(2, warn,
1397 "Redirect: from host or unauthorized router\n");
1398 return;
1399 }
1400#endif
1401
1402 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1403 ND_PRINTK(2, warn,
1404 "Redirect: source address is not link-local\n");
1405 return;
1406 }
1407
1408 optlen = skb->tail - skb->transport_header;
1409 optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1410
1411 if (optlen < 0) {
1412 ND_PRINTK(2, warn, "Redirect: packet too short\n");
1413 return;
1414 }
1415
1416 icmph = icmp6_hdr(skb);
1417 target = (const struct in6_addr *) (icmph + 1);
1418 dest = target + 1;
1419
1420 if (ipv6_addr_is_multicast(dest)) {
1421 ND_PRINTK(2, warn,
1422 "Redirect: destination address is multicast\n");
1423 return;
1424 }
1425
1426 if (ipv6_addr_equal(dest, target)) {
1427 on_link = 1;
1428 } else if (ipv6_addr_type(target) !=
1429 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1430 ND_PRINTK(2, warn,
1431 "Redirect: target address is not link-local unicast\n");
1432 return;
1433 }
1434
1435 in6_dev = __in6_dev_get(skb->dev);
1436 if (!in6_dev)
1437 return;
1438 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
1439 return;
1440
1441 /* RFC2461 8.1:
1442 * The IP source address of the Redirect MUST be the same as the current
1443 * first-hop router for the specified ICMP Destination Address.
1444 */
1445
1446 if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
1447 ND_PRINTK(2, warn, "Redirect: invalid ND options\n");
1448 return;
1449 }
1450 if (ndopts.nd_opts_tgt_lladdr) {
1451 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
1452 skb->dev);
1453 if (!lladdr) {
1454 ND_PRINTK(2, warn,
1455 "Redirect: invalid link-layer address length\n");
1456 return;
1457 }
1458 }
1459
1460 neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
1461 if (neigh) {
1462 rt6_redirect(dest, &ipv6_hdr(skb)->daddr,
1463 &ipv6_hdr(skb)->saddr, neigh, lladdr,
1464 on_link);
1465 neigh_release(neigh);
1466 }
1467}
1468
1469void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
1470{
1471 struct net_device *dev = skb->dev;
1472 struct net *net = dev_net(dev);
1473 struct sock *sk = net->ipv6.ndisc_sk;
1474 int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1475 struct sk_buff *buff;
1476 struct icmp6hdr *icmph;
1477 struct in6_addr saddr_buf;
1478 struct in6_addr *addrp;
1479 struct rt6_info *rt;
1480 struct dst_entry *dst;
1481 struct inet6_dev *idev;
1482 struct flowi6 fl6;
1483 u8 *opt;
1484 int hlen, tlen;
1485 int rd_len;
1486 int err;
1487 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
1488
1489 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1490 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
1491 dev->name);
1492 return;
1493 }
1494
1495 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1496 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1497 ND_PRINTK(2, warn,
1498 "Redirect: target address is not link-local unicast\n");
1499 return;
1500 }
1501
1502 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1503 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1504
1505 dst = ip6_route_output(net, NULL, &fl6);
1506 if (dst->error) {
1507 dst_release(dst);
1508 return;
1509 }
1510 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1511 if (IS_ERR(dst))
1512 return;
1513
1514 rt = (struct rt6_info *) dst;
1515
1516 if (rt->rt6i_flags & RTF_GATEWAY) {
1517 ND_PRINTK(2, warn,
1518 "Redirect: destination is not a neighbour\n");
1519 goto release;
1520 }
1521 if (!rt->rt6i_peer)
1522 rt6_bind_peer(rt, 1);
1523 if (!inet_peer_xrlim_allow(rt->rt6i_peer, 1*HZ))
1524 goto release;
1525
1526 if (dev->addr_len) {
1527 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target);
1528 if (!neigh) {
1529 ND_PRINTK(2, warn,
1530 "Redirect: no neigh for target address\n");
1531 goto release;
1532 }
1533
1534 read_lock_bh(&neigh->lock);
1535 if (neigh->nud_state & NUD_VALID) {
1536 memcpy(ha_buf, neigh->ha, dev->addr_len);
1537 read_unlock_bh(&neigh->lock);
1538 ha = ha_buf;
1539 len += ndisc_opt_addr_space(dev);
1540 } else
1541 read_unlock_bh(&neigh->lock);
1542
1543 neigh_release(neigh);
1544 }
1545
1546 rd_len = min_t(unsigned int,
1547 IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
1548 rd_len &= ~0x7;
1549 len += rd_len;
1550
1551 hlen = LL_RESERVED_SPACE(dev);
1552 tlen = dev->needed_tailroom;
1553 buff = sock_alloc_send_skb(sk,
1554 (MAX_HEADER + sizeof(struct ipv6hdr) +
1555 len + hlen + tlen),
1556 1, &err);
1557 if (buff == NULL) {
1558 ND_PRINTK(0, err,
1559 "Redirect: %s failed to allocate an skb, err=%d\n",
1560 __func__, err);
1561 goto release;
1562 }
1563
1564 skb_reserve(buff, hlen);
1565 ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,
1566 IPPROTO_ICMPV6, len);
1567
1568 skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
1569 skb_put(buff, len);
1570 icmph = icmp6_hdr(buff);
1571
1572 memset(icmph, 0, sizeof(struct icmp6hdr));
1573 icmph->icmp6_type = NDISC_REDIRECT;
1574
1575 /*
1576 * copy target and destination addresses
1577 */
1578
1579 addrp = (struct in6_addr *)(icmph + 1);
1580 *addrp = *target;
1581 addrp++;
1582 *addrp = ipv6_hdr(skb)->daddr;
1583
1584 opt = (u8*) (addrp + 1);
1585
1586 /*
1587 * include target_address option
1588 */
1589
1590 if (ha)
1591 opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha,
1592 dev->addr_len, dev->type);
1593
1594 /*
1595 * build redirect option and copy skb over to the new packet.
1596 */
1597
1598 memset(opt, 0, 8);
1599 *(opt++) = ND_OPT_REDIRECT_HDR;
1600 *(opt++) = (rd_len >> 3);
1601 opt += 6;
1602
1603 memcpy(opt, ipv6_hdr(skb), rd_len - 8);
1604
1605 icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr,
1606 len, IPPROTO_ICMPV6,
1607 csum_partial(icmph, len, 0));
1608
1609 skb_dst_set(buff, dst);
1610 rcu_read_lock();
1611 idev = __in6_dev_get(dst->dev);
1612 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1613 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, buff, NULL, dst->dev,
1614 dst_output);
1615 if (!err) {
1616 ICMP6MSGOUT_INC_STATS(net, idev, NDISC_REDIRECT);
1617 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1618 }
1619
1620 rcu_read_unlock();
1621 return;
1622
1623release:
1624 dst_release(dst);
1625}
1626
1627static void pndisc_redo(struct sk_buff *skb)
1628{
1629 ndisc_recv_ns(skb);
1630 kfree_skb(skb);
1631}
1632
1633int ndisc_rcv(struct sk_buff *skb)
1634{
1635 struct nd_msg *msg;
1636
1637 if (!pskb_may_pull(skb, skb->len))
1638 return 0;
1639
1640 msg = (struct nd_msg *)skb_transport_header(skb);
1641
1642 __skb_push(skb, skb->data - skb_transport_header(skb));
1643
1644 if (ipv6_hdr(skb)->hop_limit != 255) {
1645 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n",
1646 ipv6_hdr(skb)->hop_limit);
1647 return 0;
1648 }
1649
1650 if (msg->icmph.icmp6_code != 0) {
1651 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n",
1652 msg->icmph.icmp6_code);
1653 return 0;
1654 }
1655
1656 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1657
1658 switch (msg->icmph.icmp6_type) {
1659 case NDISC_NEIGHBOUR_SOLICITATION:
1660 ndisc_recv_ns(skb);
1661 break;
1662
1663 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1664 ndisc_recv_na(skb);
1665 break;
1666
1667 case NDISC_ROUTER_SOLICITATION:
1668 ndisc_recv_rs(skb);
1669 break;
1670
1671 case NDISC_ROUTER_ADVERTISEMENT:
1672 ndisc_router_discovery(skb);
1673 break;
1674
1675 case NDISC_REDIRECT:
1676 ndisc_redirect_rcv(skb);
1677 break;
1678 }
1679
1680 return 0;
1681}
1682
1683static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1684{
1685 struct net_device *dev = ptr;
1686 struct net *net = dev_net(dev);
1687
1688 switch (event) {
1689 case NETDEV_CHANGEADDR:
1690 neigh_changeaddr(&nd_tbl, dev);
1691 fib6_run_gc(~0UL, net);
1692 break;
1693 case NETDEV_DOWN:
1694 neigh_ifdown(&nd_tbl, dev);
1695 fib6_run_gc(~0UL, net);
1696 break;
1697 case NETDEV_NOTIFY_PEERS:
1698 ndisc_send_unsol_na(dev);
1699 break;
1700 default:
1701 break;
1702 }
1703
1704 return NOTIFY_DONE;
1705}
1706
1707static struct notifier_block ndisc_netdev_notifier = {
1708 .notifier_call = ndisc_netdev_event,
1709};
1710
1711#ifdef CONFIG_SYSCTL
1712static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1713 const char *func, const char *dev_name)
1714{
1715 static char warncomm[TASK_COMM_LEN];
1716 static int warned;
1717 if (strcmp(warncomm, current->comm) && warned < 5) {
1718 strcpy(warncomm, current->comm);
1719 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
1720 warncomm, func,
1721 dev_name, ctl->procname,
1722 dev_name, ctl->procname);
1723 warned++;
1724 }
1725}
1726
1727int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
1728{
1729 struct net_device *dev = ctl->extra1;
1730 struct inet6_dev *idev;
1731 int ret;
1732
1733 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1734 (strcmp(ctl->procname, "base_reachable_time") == 0))
1735 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1736
1737 if (strcmp(ctl->procname, "retrans_time") == 0)
1738 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1739
1740 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1741 ret = proc_dointvec_jiffies(ctl, write,
1742 buffer, lenp, ppos);
1743
1744 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1745 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1746 ret = proc_dointvec_ms_jiffies(ctl, write,
1747 buffer, lenp, ppos);
1748 else
1749 ret = -1;
1750
1751 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1752 if (ctl->data == &idev->nd_parms->base_reachable_time)
1753 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1754 idev->tstamp = jiffies;
1755 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1756 in6_dev_put(idev);
1757 }
1758 return ret;
1759}
1760
1761
1762#endif
1763
1764static int __net_init ndisc_net_init(struct net *net)
1765{
1766 struct ipv6_pinfo *np;
1767 struct sock *sk;
1768 int err;
1769
1770 err = inet_ctl_sock_create(&sk, PF_INET6,
1771 SOCK_RAW, IPPROTO_ICMPV6, net);
1772 if (err < 0) {
1773 ND_PRINTK(0, err,
1774 "NDISC: Failed to initialize the control socket (err %d)\n",
1775 err);
1776 return err;
1777 }
1778
1779 net->ipv6.ndisc_sk = sk;
1780
1781 np = inet6_sk(sk);
1782 np->hop_limit = 255;
1783 /* Do not loopback ndisc messages */
1784 np->mc_loop = 0;
1785
1786 return 0;
1787}
1788
1789static void __net_exit ndisc_net_exit(struct net *net)
1790{
1791 inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
1792}
1793
1794static struct pernet_operations ndisc_net_ops = {
1795 .init = ndisc_net_init,
1796 .exit = ndisc_net_exit,
1797};
1798
1799int __init ndisc_init(void)
1800{
1801 int err;
1802
1803 err = register_pernet_subsys(&ndisc_net_ops);
1804 if (err)
1805 return err;
1806 /*
1807 * Initialize the neighbour table
1808 */
1809 neigh_table_init(&nd_tbl);
1810
1811#ifdef CONFIG_SYSCTL
1812 err = neigh_sysctl_register(NULL, &nd_tbl.parms, "ipv6",
1813 &ndisc_ifinfo_sysctl_change);
1814 if (err)
1815 goto out_unregister_pernet;
1816#endif
1817 err = register_netdevice_notifier(&ndisc_netdev_notifier);
1818 if (err)
1819 goto out_unregister_sysctl;
1820out:
1821 return err;
1822
1823out_unregister_sysctl:
1824#ifdef CONFIG_SYSCTL
1825 neigh_sysctl_unregister(&nd_tbl.parms);
1826out_unregister_pernet:
1827#endif
1828 unregister_pernet_subsys(&ndisc_net_ops);
1829 goto out;
1830}
1831
1832void ndisc_cleanup(void)
1833{
1834 unregister_netdevice_notifier(&ndisc_netdev_notifier);
1835#ifdef CONFIG_SYSCTL
1836 neigh_sysctl_unregister(&nd_tbl.parms);
1837#endif
1838 neigh_table_clear(&nd_tbl);
1839 unregister_pernet_subsys(&ndisc_net_ops);
1840}